1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * NET3 Protocol independent device support routines.
4 *
5 * Derived from the non IP parts of dev.c 1.0.19
6 * Authors: Ross Biro
7 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
8 * Mark Evans, <evansmp@uhura.aston.ac.uk>
9 *
10 * Additional Authors:
11 * Florian la Roche <rzsfl@rz.uni-sb.de>
12 * Alan Cox <gw4pts@gw4pts.ampr.org>
13 * David Hinds <dahinds@users.sourceforge.net>
14 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
15 * Adam Sulmicki <adam@cfar.umd.edu>
16 * Pekka Riikonen <priikone@poesidon.pspt.fi>
17 *
18 * Changes:
19 * D.J. Barrow : Fixed bug where dev->refcnt gets set
20 * to 2 if register_netdev gets called
21 * before net_dev_init & also removed a
22 * few lines of code in the process.
23 * Alan Cox : device private ioctl copies fields back.
24 * Alan Cox : Transmit queue code does relevant
25 * stunts to keep the queue safe.
26 * Alan Cox : Fixed double lock.
27 * Alan Cox : Fixed promisc NULL pointer trap
28 * ???????? : Support the full private ioctl range
29 * Alan Cox : Moved ioctl permission check into
30 * drivers
31 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI
32 * Alan Cox : 100 backlog just doesn't cut it when
33 * you start doing multicast video 8)
34 * Alan Cox : Rewrote net_bh and list manager.
35 * Alan Cox : Fix ETH_P_ALL echoback lengths.
36 * Alan Cox : Took out transmit every packet pass
37 * Saved a few bytes in the ioctl handler
38 * Alan Cox : Network driver sets packet type before
39 * calling netif_rx. Saves a function
40 * call a packet.
41 * Alan Cox : Hashed net_bh()
42 * Richard Kooijman: Timestamp fixes.
43 * Alan Cox : Wrong field in SIOCGIFDSTADDR
44 * Alan Cox : Device lock protection.
45 * Alan Cox : Fixed nasty side effect of device close
46 * changes.
47 * Rudi Cilibrasi : Pass the right thing to
48 * set_mac_address()
49 * Dave Miller : 32bit quantity for the device lock to
50 * make it work out on a Sparc.
51 * Bjorn Ekwall : Added KERNELD hack.
52 * Alan Cox : Cleaned up the backlog initialise.
53 * Craig Metz : SIOCGIFCONF fix if space for under
54 * 1 device.
55 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there
56 * is no device open function.
57 * Andi Kleen : Fix error reporting for SIOCGIFCONF
58 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF
59 * Cyrus Durgin : Cleaned for KMOD
60 * Adam Sulmicki : Bug Fix : Network Device Unload
61 * A network device unload needs to purge
62 * the backlog queue.
63 * Paul Rusty Russell : SIOCSIFNAME
64 * Pekka Riikonen : Netdev boot-time settings code
65 * Andrew Morton : Make unregister_netdevice wait
66 * indefinitely on dev->refcnt
67 * J Hadi Salim : - Backlog queue sampling
68 * - netif_rx() feedback
69 */
70
71#include <linux/uaccess.h>
72#include <linux/bitmap.h>
73#include <linux/capability.h>
74#include <linux/cpu.h>
75#include <linux/types.h>
76#include <linux/kernel.h>
77#include <linux/hash.h>
78#include <linux/slab.h>
79#include <linux/sched.h>
80#include <linux/sched/mm.h>
81#include <linux/mutex.h>
82#include <linux/rwsem.h>
83#include <linux/string.h>
84#include <linux/mm.h>
85#include <linux/socket.h>
86#include <linux/sockios.h>
87#include <linux/errno.h>
88#include <linux/interrupt.h>
89#include <linux/if_ether.h>
90#include <linux/netdevice.h>
91#include <linux/etherdevice.h>
92#include <linux/ethtool.h>
93#include <linux/skbuff.h>
94#include <linux/kthread.h>
95#include <linux/bpf.h>
96#include <linux/bpf_trace.h>
97#include <net/net_namespace.h>
98#include <net/sock.h>
99#include <net/busy_poll.h>
100#include <linux/rtnetlink.h>
101#include <linux/stat.h>
102#include <net/dsa.h>
103#include <net/dst.h>
104#include <net/dst_metadata.h>
105#include <net/gro.h>
106#include <net/pkt_sched.h>
107#include <net/pkt_cls.h>
108#include <net/checksum.h>
109#include <net/xfrm.h>
110#include <net/tcx.h>
111#include <linux/highmem.h>
112#include <linux/init.h>
113#include <linux/module.h>
114#include <linux/netpoll.h>
115#include <linux/rcupdate.h>
116#include <linux/delay.h>
117#include <net/iw_handler.h>
118#include <asm/current.h>
119#include <linux/audit.h>
120#include <linux/dmaengine.h>
121#include <linux/err.h>
122#include <linux/ctype.h>
123#include <linux/if_arp.h>
124#include <linux/if_vlan.h>
125#include <linux/ip.h>
126#include <net/ip.h>
127#include <net/mpls.h>
128#include <linux/ipv6.h>
129#include <linux/in.h>
130#include <linux/jhash.h>
131#include <linux/random.h>
132#include <trace/events/napi.h>
133#include <trace/events/net.h>
134#include <trace/events/skb.h>
135#include <trace/events/qdisc.h>
136#include <trace/events/xdp.h>
137#include <linux/inetdevice.h>
138#include <linux/cpu_rmap.h>
139#include <linux/static_key.h>
140#include <linux/hashtable.h>
141#include <linux/vmalloc.h>
142#include <linux/if_macvlan.h>
143#include <linux/errqueue.h>
144#include <linux/hrtimer.h>
145#include <linux/netfilter_netdev.h>
146#include <linux/crash_dump.h>
147#include <linux/sctp.h>
148#include <net/udp_tunnel.h>
149#include <linux/net_namespace.h>
150#include <linux/indirect_call_wrapper.h>
151#include <net/devlink.h>
152#include <linux/pm_runtime.h>
153#include <linux/prandom.h>
154#include <linux/once_lite.h>
155#include <net/netdev_rx_queue.h>
156
157#include "dev.h"
158#include "net-sysfs.h"
159
160static DEFINE_SPINLOCK(ptype_lock);
161struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
162struct list_head ptype_all __read_mostly; /* Taps */
163
164static int netif_rx_internal(struct sk_buff *skb);
165static int call_netdevice_notifiers_extack(unsigned long val,
166 struct net_device *dev,
167 struct netlink_ext_ack *extack);
168static struct napi_struct *napi_by_id(unsigned int napi_id);
169
170/*
171 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
172 * semaphore.
173 *
174 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
175 *
176 * Writers must hold the rtnl semaphore while they loop through the
177 * dev_base_head list, and hold dev_base_lock for writing when they do the
178 * actual updates. This allows pure readers to access the list even
179 * while a writer is preparing to update it.
180 *
181 * To put it another way, dev_base_lock is held for writing only to
182 * protect against pure readers; the rtnl semaphore provides the
183 * protection against other writers.
184 *
185 * See, for example usages, register_netdevice() and
186 * unregister_netdevice(), which must be called with the rtnl
187 * semaphore held.
188 */
189DEFINE_RWLOCK(dev_base_lock);
190EXPORT_SYMBOL(dev_base_lock);
191
192static DEFINE_MUTEX(ifalias_mutex);
193
194/* protects napi_hash addition/deletion and napi_gen_id */
195static DEFINE_SPINLOCK(napi_hash_lock);
196
197static unsigned int napi_gen_id = NR_CPUS;
198static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
199
200static DECLARE_RWSEM(devnet_rename_sem);
201
202static inline void dev_base_seq_inc(struct net *net)
203{
204 while (++net->dev_base_seq == 0)
205 ;
206}
207
208static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
209{
210 unsigned int hash = full_name_hash(salt: net, name, strnlen(p: name, IFNAMSIZ));
211
212 return &net->dev_name_head[hash_32(val: hash, NETDEV_HASHBITS)];
213}
214
215static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
216{
217 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
218}
219
220static inline void rps_lock_irqsave(struct softnet_data *sd,
221 unsigned long *flags)
222{
223 if (IS_ENABLED(CONFIG_RPS))
224 spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags);
225 else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
226 local_irq_save(*flags);
227}
228
229static inline void rps_lock_irq_disable(struct softnet_data *sd)
230{
231 if (IS_ENABLED(CONFIG_RPS))
232 spin_lock_irq(lock: &sd->input_pkt_queue.lock);
233 else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
234 local_irq_disable();
235}
236
237static inline void rps_unlock_irq_restore(struct softnet_data *sd,
238 unsigned long *flags)
239{
240 if (IS_ENABLED(CONFIG_RPS))
241 spin_unlock_irqrestore(lock: &sd->input_pkt_queue.lock, flags: *flags);
242 else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
243 local_irq_restore(*flags);
244}
245
246static inline void rps_unlock_irq_enable(struct softnet_data *sd)
247{
248 if (IS_ENABLED(CONFIG_RPS))
249 spin_unlock_irq(lock: &sd->input_pkt_queue.lock);
250 else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
251 local_irq_enable();
252}
253
254static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev,
255 const char *name)
256{
257 struct netdev_name_node *name_node;
258
259 name_node = kmalloc(size: sizeof(*name_node), GFP_KERNEL);
260 if (!name_node)
261 return NULL;
262 INIT_HLIST_NODE(h: &name_node->hlist);
263 name_node->dev = dev;
264 name_node->name = name;
265 return name_node;
266}
267
268static struct netdev_name_node *
269netdev_name_node_head_alloc(struct net_device *dev)
270{
271 struct netdev_name_node *name_node;
272
273 name_node = netdev_name_node_alloc(dev, name: dev->name);
274 if (!name_node)
275 return NULL;
276 INIT_LIST_HEAD(list: &name_node->list);
277 return name_node;
278}
279
280static void netdev_name_node_free(struct netdev_name_node *name_node)
281{
282 kfree(objp: name_node);
283}
284
285static void netdev_name_node_add(struct net *net,
286 struct netdev_name_node *name_node)
287{
288 hlist_add_head_rcu(n: &name_node->hlist,
289 h: dev_name_hash(net, name: name_node->name));
290}
291
292static void netdev_name_node_del(struct netdev_name_node *name_node)
293{
294 hlist_del_rcu(n: &name_node->hlist);
295}
296
297static struct netdev_name_node *netdev_name_node_lookup(struct net *net,
298 const char *name)
299{
300 struct hlist_head *head = dev_name_hash(net, name);
301 struct netdev_name_node *name_node;
302
303 hlist_for_each_entry(name_node, head, hlist)
304 if (!strcmp(name_node->name, name))
305 return name_node;
306 return NULL;
307}
308
309static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net,
310 const char *name)
311{
312 struct hlist_head *head = dev_name_hash(net, name);
313 struct netdev_name_node *name_node;
314
315 hlist_for_each_entry_rcu(name_node, head, hlist)
316 if (!strcmp(name_node->name, name))
317 return name_node;
318 return NULL;
319}
320
321bool netdev_name_in_use(struct net *net, const char *name)
322{
323 return netdev_name_node_lookup(net, name);
324}
325EXPORT_SYMBOL(netdev_name_in_use);
326
327int netdev_name_node_alt_create(struct net_device *dev, const char *name)
328{
329 struct netdev_name_node *name_node;
330 struct net *net = dev_net(dev);
331
332 name_node = netdev_name_node_lookup(net, name);
333 if (name_node)
334 return -EEXIST;
335 name_node = netdev_name_node_alloc(dev, name);
336 if (!name_node)
337 return -ENOMEM;
338 netdev_name_node_add(net, name_node);
339 /* The node that holds dev->name acts as a head of per-device list. */
340 list_add_tail(new: &name_node->list, head: &dev->name_node->list);
341
342 return 0;
343}
344
345static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node)
346{
347 list_del(entry: &name_node->list);
348 kfree(objp: name_node->name);
349 netdev_name_node_free(name_node);
350}
351
352int netdev_name_node_alt_destroy(struct net_device *dev, const char *name)
353{
354 struct netdev_name_node *name_node;
355 struct net *net = dev_net(dev);
356
357 name_node = netdev_name_node_lookup(net, name);
358 if (!name_node)
359 return -ENOENT;
360 /* lookup might have found our primary name or a name belonging
361 * to another device.
362 */
363 if (name_node == dev->name_node || name_node->dev != dev)
364 return -EINVAL;
365
366 netdev_name_node_del(name_node);
367 synchronize_rcu();
368 __netdev_name_node_alt_destroy(name_node);
369
370 return 0;
371}
372
373static void netdev_name_node_alt_flush(struct net_device *dev)
374{
375 struct netdev_name_node *name_node, *tmp;
376
377 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list)
378 __netdev_name_node_alt_destroy(name_node);
379}
380
381/* Device list insertion */
382static void list_netdevice(struct net_device *dev)
383{
384 struct netdev_name_node *name_node;
385 struct net *net = dev_net(dev);
386
387 ASSERT_RTNL();
388
389 write_lock(&dev_base_lock);
390 list_add_tail_rcu(new: &dev->dev_list, head: &net->dev_base_head);
391 netdev_name_node_add(net, name_node: dev->name_node);
392 hlist_add_head_rcu(n: &dev->index_hlist,
393 h: dev_index_hash(net, ifindex: dev->ifindex));
394 write_unlock(&dev_base_lock);
395
396 netdev_for_each_altname(dev, name_node)
397 netdev_name_node_add(net, name_node);
398
399 /* We reserved the ifindex, this can't fail */
400 WARN_ON(xa_store(&net->dev_by_index, dev->ifindex, dev, GFP_KERNEL));
401
402 dev_base_seq_inc(net);
403}
404
405/* Device list removal
406 * caller must respect a RCU grace period before freeing/reusing dev
407 */
408static void unlist_netdevice(struct net_device *dev, bool lock)
409{
410 struct netdev_name_node *name_node;
411 struct net *net = dev_net(dev);
412
413 ASSERT_RTNL();
414
415 xa_erase(&net->dev_by_index, index: dev->ifindex);
416
417 netdev_for_each_altname(dev, name_node)
418 netdev_name_node_del(name_node);
419
420 /* Unlink dev from the device chain */
421 if (lock)
422 write_lock(&dev_base_lock);
423 list_del_rcu(entry: &dev->dev_list);
424 netdev_name_node_del(name_node: dev->name_node);
425 hlist_del_rcu(n: &dev->index_hlist);
426 if (lock)
427 write_unlock(&dev_base_lock);
428
429 dev_base_seq_inc(net: dev_net(dev));
430}
431
432/*
433 * Our notifier list
434 */
435
436static RAW_NOTIFIER_HEAD(netdev_chain);
437
438/*
439 * Device drivers call our routines to queue packets here. We empty the
440 * queue in the local softnet handler.
441 */
442
443DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
444EXPORT_PER_CPU_SYMBOL(softnet_data);
445
446#ifdef CONFIG_LOCKDEP
447/*
448 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
449 * according to dev->type
450 */
451static const unsigned short netdev_lock_type[] = {
452 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
453 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
454 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
455 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
456 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
457 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
458 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
459 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
460 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
461 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
462 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
463 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
464 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
465 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
466 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
467
468static const char *const netdev_lock_name[] = {
469 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
470 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
471 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
472 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
473 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
474 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
475 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
476 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
477 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
478 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
479 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
480 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
481 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
482 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
483 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
484
485static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
486static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
487
488static inline unsigned short netdev_lock_pos(unsigned short dev_type)
489{
490 int i;
491
492 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
493 if (netdev_lock_type[i] == dev_type)
494 return i;
495 /* the last key is used by default */
496 return ARRAY_SIZE(netdev_lock_type) - 1;
497}
498
499static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
500 unsigned short dev_type)
501{
502 int i;
503
504 i = netdev_lock_pos(dev_type);
505 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
506 netdev_lock_name[i]);
507}
508
509static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
510{
511 int i;
512
513 i = netdev_lock_pos(dev_type: dev->type);
514 lockdep_set_class_and_name(&dev->addr_list_lock,
515 &netdev_addr_lock_key[i],
516 netdev_lock_name[i]);
517}
518#else
519static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
520 unsigned short dev_type)
521{
522}
523
524static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
525{
526}
527#endif
528
529/*******************************************************************************
530 *
531 * Protocol management and registration routines
532 *
533 *******************************************************************************/
534
535
536/*
537 * Add a protocol ID to the list. Now that the input handler is
538 * smarter we can dispense with all the messy stuff that used to be
539 * here.
540 *
541 * BEWARE!!! Protocol handlers, mangling input packets,
542 * MUST BE last in hash buckets and checking protocol handlers
543 * MUST start from promiscuous ptype_all chain in net_bh.
544 * It is true now, do not change it.
545 * Explanation follows: if protocol handler, mangling packet, will
546 * be the first on list, it is not able to sense, that packet
547 * is cloned and should be copied-on-write, so that it will
548 * change it and subsequent readers will get broken packet.
549 * --ANK (980803)
550 */
551
552static inline struct list_head *ptype_head(const struct packet_type *pt)
553{
554 if (pt->type == htons(ETH_P_ALL))
555 return pt->dev ? &pt->dev->ptype_all : &ptype_all;
556 else
557 return pt->dev ? &pt->dev->ptype_specific :
558 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
559}
560
561/**
562 * dev_add_pack - add packet handler
563 * @pt: packet type declaration
564 *
565 * Add a protocol handler to the networking stack. The passed &packet_type
566 * is linked into kernel lists and may not be freed until it has been
567 * removed from the kernel lists.
568 *
569 * This call does not sleep therefore it can not
570 * guarantee all CPU's that are in middle of receiving packets
571 * will see the new packet type (until the next received packet).
572 */
573
574void dev_add_pack(struct packet_type *pt)
575{
576 struct list_head *head = ptype_head(pt);
577
578 spin_lock(lock: &ptype_lock);
579 list_add_rcu(new: &pt->list, head);
580 spin_unlock(lock: &ptype_lock);
581}
582EXPORT_SYMBOL(dev_add_pack);
583
584/**
585 * __dev_remove_pack - remove packet handler
586 * @pt: packet type declaration
587 *
588 * Remove a protocol handler that was previously added to the kernel
589 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
590 * from the kernel lists and can be freed or reused once this function
591 * returns.
592 *
593 * The packet type might still be in use by receivers
594 * and must not be freed until after all the CPU's have gone
595 * through a quiescent state.
596 */
597void __dev_remove_pack(struct packet_type *pt)
598{
599 struct list_head *head = ptype_head(pt);
600 struct packet_type *pt1;
601
602 spin_lock(lock: &ptype_lock);
603
604 list_for_each_entry(pt1, head, list) {
605 if (pt == pt1) {
606 list_del_rcu(entry: &pt->list);
607 goto out;
608 }
609 }
610
611 pr_warn("dev_remove_pack: %p not found\n", pt);
612out:
613 spin_unlock(lock: &ptype_lock);
614}
615EXPORT_SYMBOL(__dev_remove_pack);
616
617/**
618 * dev_remove_pack - remove packet handler
619 * @pt: packet type declaration
620 *
621 * Remove a protocol handler that was previously added to the kernel
622 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
623 * from the kernel lists and can be freed or reused once this function
624 * returns.
625 *
626 * This call sleeps to guarantee that no CPU is looking at the packet
627 * type after return.
628 */
629void dev_remove_pack(struct packet_type *pt)
630{
631 __dev_remove_pack(pt);
632
633 synchronize_net();
634}
635EXPORT_SYMBOL(dev_remove_pack);
636
637
638/*******************************************************************************
639 *
640 * Device Interface Subroutines
641 *
642 *******************************************************************************/
643
644/**
645 * dev_get_iflink - get 'iflink' value of a interface
646 * @dev: targeted interface
647 *
648 * Indicates the ifindex the interface is linked to.
649 * Physical interfaces have the same 'ifindex' and 'iflink' values.
650 */
651
652int dev_get_iflink(const struct net_device *dev)
653{
654 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
655 return dev->netdev_ops->ndo_get_iflink(dev);
656
657 return dev->ifindex;
658}
659EXPORT_SYMBOL(dev_get_iflink);
660
661/**
662 * dev_fill_metadata_dst - Retrieve tunnel egress information.
663 * @dev: targeted interface
664 * @skb: The packet.
665 *
666 * For better visibility of tunnel traffic OVS needs to retrieve
667 * egress tunnel information for a packet. Following API allows
668 * user to get this info.
669 */
670int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
671{
672 struct ip_tunnel_info *info;
673
674 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst)
675 return -EINVAL;
676
677 info = skb_tunnel_info_unclone(skb);
678 if (!info)
679 return -ENOMEM;
680 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
681 return -EINVAL;
682
683 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
684}
685EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);
686
687static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack)
688{
689 int k = stack->num_paths++;
690
691 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX))
692 return NULL;
693
694 return &stack->path[k];
695}
696
697int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr,
698 struct net_device_path_stack *stack)
699{
700 const struct net_device *last_dev;
701 struct net_device_path_ctx ctx = {
702 .dev = dev,
703 };
704 struct net_device_path *path;
705 int ret = 0;
706
707 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr));
708 stack->num_paths = 0;
709 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) {
710 last_dev = ctx.dev;
711 path = dev_fwd_path(stack);
712 if (!path)
713 return -1;
714
715 memset(path, 0, sizeof(struct net_device_path));
716 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path);
717 if (ret < 0)
718 return -1;
719
720 if (WARN_ON_ONCE(last_dev == ctx.dev))
721 return -1;
722 }
723
724 if (!ctx.dev)
725 return ret;
726
727 path = dev_fwd_path(stack);
728 if (!path)
729 return -1;
730 path->type = DEV_PATH_ETHERNET;
731 path->dev = ctx.dev;
732
733 return ret;
734}
735EXPORT_SYMBOL_GPL(dev_fill_forward_path);
736
737/**
738 * __dev_get_by_name - find a device by its name
739 * @net: the applicable net namespace
740 * @name: name to find
741 *
742 * Find an interface by name. Must be called under RTNL semaphore
743 * or @dev_base_lock. If the name is found a pointer to the device
744 * is returned. If the name is not found then %NULL is returned. The
745 * reference counters are not incremented so the caller must be
746 * careful with locks.
747 */
748
749struct net_device *__dev_get_by_name(struct net *net, const char *name)
750{
751 struct netdev_name_node *node_name;
752
753 node_name = netdev_name_node_lookup(net, name);
754 return node_name ? node_name->dev : NULL;
755}
756EXPORT_SYMBOL(__dev_get_by_name);
757
758/**
759 * dev_get_by_name_rcu - find a device by its name
760 * @net: the applicable net namespace
761 * @name: name to find
762 *
763 * Find an interface by name.
764 * If the name is found a pointer to the device is returned.
765 * If the name is not found then %NULL is returned.
766 * The reference counters are not incremented so the caller must be
767 * careful with locks. The caller must hold RCU lock.
768 */
769
770struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
771{
772 struct netdev_name_node *node_name;
773
774 node_name = netdev_name_node_lookup_rcu(net, name);
775 return node_name ? node_name->dev : NULL;
776}
777EXPORT_SYMBOL(dev_get_by_name_rcu);
778
779/* Deprecated for new users, call netdev_get_by_name() instead */
780struct net_device *dev_get_by_name(struct net *net, const char *name)
781{
782 struct net_device *dev;
783
784 rcu_read_lock();
785 dev = dev_get_by_name_rcu(net, name);
786 dev_hold(dev);
787 rcu_read_unlock();
788 return dev;
789}
790EXPORT_SYMBOL(dev_get_by_name);
791
792/**
793 * netdev_get_by_name() - find a device by its name
794 * @net: the applicable net namespace
795 * @name: name to find
796 * @tracker: tracking object for the acquired reference
797 * @gfp: allocation flags for the tracker
798 *
799 * Find an interface by name. This can be called from any
800 * context and does its own locking. The returned handle has
801 * the usage count incremented and the caller must use netdev_put() to
802 * release it when it is no longer needed. %NULL is returned if no
803 * matching device is found.
804 */
805struct net_device *netdev_get_by_name(struct net *net, const char *name,
806 netdevice_tracker *tracker, gfp_t gfp)
807{
808 struct net_device *dev;
809
810 dev = dev_get_by_name(net, name);
811 if (dev)
812 netdev_tracker_alloc(dev, tracker, gfp);
813 return dev;
814}
815EXPORT_SYMBOL(netdev_get_by_name);
816
817/**
818 * __dev_get_by_index - find a device by its ifindex
819 * @net: the applicable net namespace
820 * @ifindex: index of device
821 *
822 * Search for an interface by index. Returns %NULL if the device
823 * is not found or a pointer to the device. The device has not
824 * had its reference counter increased so the caller must be careful
825 * about locking. The caller must hold either the RTNL semaphore
826 * or @dev_base_lock.
827 */
828
829struct net_device *__dev_get_by_index(struct net *net, int ifindex)
830{
831 struct net_device *dev;
832 struct hlist_head *head = dev_index_hash(net, ifindex);
833
834 hlist_for_each_entry(dev, head, index_hlist)
835 if (dev->ifindex == ifindex)
836 return dev;
837
838 return NULL;
839}
840EXPORT_SYMBOL(__dev_get_by_index);
841
842/**
843 * dev_get_by_index_rcu - find a device by its ifindex
844 * @net: the applicable net namespace
845 * @ifindex: index of device
846 *
847 * Search for an interface by index. Returns %NULL if the device
848 * is not found or a pointer to the device. The device has not
849 * had its reference counter increased so the caller must be careful
850 * about locking. The caller must hold RCU lock.
851 */
852
853struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
854{
855 struct net_device *dev;
856 struct hlist_head *head = dev_index_hash(net, ifindex);
857
858 hlist_for_each_entry_rcu(dev, head, index_hlist)
859 if (dev->ifindex == ifindex)
860 return dev;
861
862 return NULL;
863}
864EXPORT_SYMBOL(dev_get_by_index_rcu);
865
866/* Deprecated for new users, call netdev_get_by_index() instead */
867struct net_device *dev_get_by_index(struct net *net, int ifindex)
868{
869 struct net_device *dev;
870
871 rcu_read_lock();
872 dev = dev_get_by_index_rcu(net, ifindex);
873 dev_hold(dev);
874 rcu_read_unlock();
875 return dev;
876}
877EXPORT_SYMBOL(dev_get_by_index);
878
879/**
880 * netdev_get_by_index() - find a device by its ifindex
881 * @net: the applicable net namespace
882 * @ifindex: index of device
883 * @tracker: tracking object for the acquired reference
884 * @gfp: allocation flags for the tracker
885 *
886 * Search for an interface by index. Returns NULL if the device
887 * is not found or a pointer to the device. The device returned has
888 * had a reference added and the pointer is safe until the user calls
889 * netdev_put() to indicate they have finished with it.
890 */
891struct net_device *netdev_get_by_index(struct net *net, int ifindex,
892 netdevice_tracker *tracker, gfp_t gfp)
893{
894 struct net_device *dev;
895
896 dev = dev_get_by_index(net, ifindex);
897 if (dev)
898 netdev_tracker_alloc(dev, tracker, gfp);
899 return dev;
900}
901EXPORT_SYMBOL(netdev_get_by_index);
902
903/**
904 * dev_get_by_napi_id - find a device by napi_id
905 * @napi_id: ID of the NAPI struct
906 *
907 * Search for an interface by NAPI ID. Returns %NULL if the device
908 * is not found or a pointer to the device. The device has not had
909 * its reference counter increased so the caller must be careful
910 * about locking. The caller must hold RCU lock.
911 */
912
913struct net_device *dev_get_by_napi_id(unsigned int napi_id)
914{
915 struct napi_struct *napi;
916
917 WARN_ON_ONCE(!rcu_read_lock_held());
918
919 if (napi_id < MIN_NAPI_ID)
920 return NULL;
921
922 napi = napi_by_id(napi_id);
923
924 return napi ? napi->dev : NULL;
925}
926EXPORT_SYMBOL(dev_get_by_napi_id);
927
928/**
929 * netdev_get_name - get a netdevice name, knowing its ifindex.
930 * @net: network namespace
931 * @name: a pointer to the buffer where the name will be stored.
932 * @ifindex: the ifindex of the interface to get the name from.
933 */
934int netdev_get_name(struct net *net, char *name, int ifindex)
935{
936 struct net_device *dev;
937 int ret;
938
939 down_read(sem: &devnet_rename_sem);
940 rcu_read_lock();
941
942 dev = dev_get_by_index_rcu(net, ifindex);
943 if (!dev) {
944 ret = -ENODEV;
945 goto out;
946 }
947
948 strcpy(p: name, q: dev->name);
949
950 ret = 0;
951out:
952 rcu_read_unlock();
953 up_read(sem: &devnet_rename_sem);
954 return ret;
955}
956
957/**
958 * dev_getbyhwaddr_rcu - find a device by its hardware address
959 * @net: the applicable net namespace
960 * @type: media type of device
961 * @ha: hardware address
962 *
963 * Search for an interface by MAC address. Returns NULL if the device
964 * is not found or a pointer to the device.
965 * The caller must hold RCU or RTNL.
966 * The returned device has not had its ref count increased
967 * and the caller must therefore be careful about locking
968 *
969 */
970
971struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
972 const char *ha)
973{
974 struct net_device *dev;
975
976 for_each_netdev_rcu(net, dev)
977 if (dev->type == type &&
978 !memcmp(p: dev->dev_addr, q: ha, size: dev->addr_len))
979 return dev;
980
981 return NULL;
982}
983EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
984
985struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
986{
987 struct net_device *dev, *ret = NULL;
988
989 rcu_read_lock();
990 for_each_netdev_rcu(net, dev)
991 if (dev->type == type) {
992 dev_hold(dev);
993 ret = dev;
994 break;
995 }
996 rcu_read_unlock();
997 return ret;
998}
999EXPORT_SYMBOL(dev_getfirstbyhwtype);
1000
1001/**
1002 * __dev_get_by_flags - find any device with given flags
1003 * @net: the applicable net namespace
1004 * @if_flags: IFF_* values
1005 * @mask: bitmask of bits in if_flags to check
1006 *
1007 * Search for any interface with the given flags. Returns NULL if a device
1008 * is not found or a pointer to the device. Must be called inside
1009 * rtnl_lock(), and result refcount is unchanged.
1010 */
1011
1012struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
1013 unsigned short mask)
1014{
1015 struct net_device *dev, *ret;
1016
1017 ASSERT_RTNL();
1018
1019 ret = NULL;
1020 for_each_netdev(net, dev) {
1021 if (((dev->flags ^ if_flags) & mask) == 0) {
1022 ret = dev;
1023 break;
1024 }
1025 }
1026 return ret;
1027}
1028EXPORT_SYMBOL(__dev_get_by_flags);
1029
1030/**
1031 * dev_valid_name - check if name is okay for network device
1032 * @name: name string
1033 *
1034 * Network device names need to be valid file names to
1035 * allow sysfs to work. We also disallow any kind of
1036 * whitespace.
1037 */
1038bool dev_valid_name(const char *name)
1039{
1040 if (*name == '\0')
1041 return false;
1042 if (strnlen(p: name, IFNAMSIZ) == IFNAMSIZ)
1043 return false;
1044 if (!strcmp(name, ".") || !strcmp(name, ".."))
1045 return false;
1046
1047 while (*name) {
1048 if (*name == '/' || *name == ':' || isspace(*name))
1049 return false;
1050 name++;
1051 }
1052 return true;
1053}
1054EXPORT_SYMBOL(dev_valid_name);
1055
1056/**
1057 * __dev_alloc_name - allocate a name for a device
1058 * @net: network namespace to allocate the device name in
1059 * @name: name format string
1060 * @res: result name string
1061 *
1062 * Passed a format string - eg "lt%d" it will try and find a suitable
1063 * id. It scans list of devices to build up a free map, then chooses
1064 * the first empty slot. The caller must hold the dev_base or rtnl lock
1065 * while allocating the name and adding the device in order to avoid
1066 * duplicates.
1067 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1068 * Returns the number of the unit assigned or a negative errno code.
1069 */
1070
1071static int __dev_alloc_name(struct net *net, const char *name, char *res)
1072{
1073 int i = 0;
1074 const char *p;
1075 const int max_netdevices = 8*PAGE_SIZE;
1076 unsigned long *inuse;
1077 struct net_device *d;
1078 char buf[IFNAMSIZ];
1079
1080 /* Verify the string as this thing may have come from the user.
1081 * There must be one "%d" and no other "%" characters.
1082 */
1083 p = strchr(name, '%');
1084 if (!p || p[1] != 'd' || strchr(p + 2, '%'))
1085 return -EINVAL;
1086
1087 /* Use one page as a bit array of possible slots */
1088 inuse = bitmap_zalloc(nbits: max_netdevices, GFP_ATOMIC);
1089 if (!inuse)
1090 return -ENOMEM;
1091
1092 for_each_netdev(net, d) {
1093 struct netdev_name_node *name_node;
1094
1095 netdev_for_each_altname(d, name_node) {
1096 if (!sscanf(name_node->name, name, &i))
1097 continue;
1098 if (i < 0 || i >= max_netdevices)
1099 continue;
1100
1101 /* avoid cases where sscanf is not exact inverse of printf */
1102 snprintf(buf, IFNAMSIZ, fmt: name, i);
1103 if (!strncmp(buf, name_node->name, IFNAMSIZ))
1104 __set_bit(i, inuse);
1105 }
1106 if (!sscanf(d->name, name, &i))
1107 continue;
1108 if (i < 0 || i >= max_netdevices)
1109 continue;
1110
1111 /* avoid cases where sscanf is not exact inverse of printf */
1112 snprintf(buf, IFNAMSIZ, fmt: name, i);
1113 if (!strncmp(buf, d->name, IFNAMSIZ))
1114 __set_bit(i, inuse);
1115 }
1116
1117 i = find_first_zero_bit(addr: inuse, size: max_netdevices);
1118 bitmap_free(bitmap: inuse);
1119 if (i == max_netdevices)
1120 return -ENFILE;
1121
1122 snprintf(buf: res, IFNAMSIZ, fmt: name, i);
1123 return i;
1124}
1125
1126/* Returns negative errno or allocated unit id (see __dev_alloc_name()) */
1127static int dev_prep_valid_name(struct net *net, struct net_device *dev,
1128 const char *want_name, char *out_name,
1129 int dup_errno)
1130{
1131 if (!dev_valid_name(want_name))
1132 return -EINVAL;
1133
1134 if (strchr(want_name, '%'))
1135 return __dev_alloc_name(net, name: want_name, res: out_name);
1136
1137 if (netdev_name_in_use(net, want_name))
1138 return -dup_errno;
1139 if (out_name != want_name)
1140 strscpy(p: out_name, q: want_name, IFNAMSIZ);
1141 return 0;
1142}
1143
1144/**
1145 * dev_alloc_name - allocate a name for a device
1146 * @dev: device
1147 * @name: name format string
1148 *
1149 * Passed a format string - eg "lt%d" it will try and find a suitable
1150 * id. It scans list of devices to build up a free map, then chooses
1151 * the first empty slot. The caller must hold the dev_base or rtnl lock
1152 * while allocating the name and adding the device in order to avoid
1153 * duplicates.
1154 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1155 * Returns the number of the unit assigned or a negative errno code.
1156 */
1157
1158int dev_alloc_name(struct net_device *dev, const char *name)
1159{
1160 return dev_prep_valid_name(net: dev_net(dev), dev, want_name: name, out_name: dev->name, ENFILE);
1161}
1162EXPORT_SYMBOL(dev_alloc_name);
1163
1164static int dev_get_valid_name(struct net *net, struct net_device *dev,
1165 const char *name)
1166{
1167 int ret;
1168
1169 ret = dev_prep_valid_name(net, dev, want_name: name, out_name: dev->name, EEXIST);
1170 return ret < 0 ? ret : 0;
1171}
1172
1173/**
1174 * dev_change_name - change name of a device
1175 * @dev: device
1176 * @newname: name (or format string) must be at least IFNAMSIZ
1177 *
1178 * Change name of a device, can pass format strings "eth%d".
1179 * for wildcarding.
1180 */
1181int dev_change_name(struct net_device *dev, const char *newname)
1182{
1183 unsigned char old_assign_type;
1184 char oldname[IFNAMSIZ];
1185 int err = 0;
1186 int ret;
1187 struct net *net;
1188
1189 ASSERT_RTNL();
1190 BUG_ON(!dev_net(dev));
1191
1192 net = dev_net(dev);
1193
1194 down_write(sem: &devnet_rename_sem);
1195
1196 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1197 up_write(sem: &devnet_rename_sem);
1198 return 0;
1199 }
1200
1201 memcpy(oldname, dev->name, IFNAMSIZ);
1202
1203 err = dev_get_valid_name(net, dev, name: newname);
1204 if (err < 0) {
1205 up_write(sem: &devnet_rename_sem);
1206 return err;
1207 }
1208
1209 if (oldname[0] && !strchr(oldname, '%'))
1210 netdev_info(dev, format: "renamed from %s%s\n", oldname,
1211 dev->flags & IFF_UP ? " (while UP)" : "");
1212
1213 old_assign_type = dev->name_assign_type;
1214 dev->name_assign_type = NET_NAME_RENAMED;
1215
1216rollback:
1217 ret = device_rename(dev: &dev->dev, new_name: dev->name);
1218 if (ret) {
1219 memcpy(dev->name, oldname, IFNAMSIZ);
1220 dev->name_assign_type = old_assign_type;
1221 up_write(sem: &devnet_rename_sem);
1222 return ret;
1223 }
1224
1225 up_write(sem: &devnet_rename_sem);
1226
1227 netdev_adjacent_rename_links(dev, oldname);
1228
1229 write_lock(&dev_base_lock);
1230 netdev_name_node_del(name_node: dev->name_node);
1231 write_unlock(&dev_base_lock);
1232
1233 synchronize_rcu();
1234
1235 write_lock(&dev_base_lock);
1236 netdev_name_node_add(net, name_node: dev->name_node);
1237 write_unlock(&dev_base_lock);
1238
1239 ret = call_netdevice_notifiers(val: NETDEV_CHANGENAME, dev);
1240 ret = notifier_to_errno(ret);
1241
1242 if (ret) {
1243 /* err >= 0 after dev_alloc_name() or stores the first errno */
1244 if (err >= 0) {
1245 err = ret;
1246 down_write(sem: &devnet_rename_sem);
1247 memcpy(dev->name, oldname, IFNAMSIZ);
1248 memcpy(oldname, newname, IFNAMSIZ);
1249 dev->name_assign_type = old_assign_type;
1250 old_assign_type = NET_NAME_RENAMED;
1251 goto rollback;
1252 } else {
1253 netdev_err(dev, format: "name change rollback failed: %d\n",
1254 ret);
1255 }
1256 }
1257
1258 return err;
1259}
1260
1261/**
1262 * dev_set_alias - change ifalias of a device
1263 * @dev: device
1264 * @alias: name up to IFALIASZ
1265 * @len: limit of bytes to copy from info
1266 *
1267 * Set ifalias for a device,
1268 */
1269int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1270{
1271 struct dev_ifalias *new_alias = NULL;
1272
1273 if (len >= IFALIASZ)
1274 return -EINVAL;
1275
1276 if (len) {
1277 new_alias = kmalloc(size: sizeof(*new_alias) + len + 1, GFP_KERNEL);
1278 if (!new_alias)
1279 return -ENOMEM;
1280
1281 memcpy(new_alias->ifalias, alias, len);
1282 new_alias->ifalias[len] = 0;
1283 }
1284
1285 mutex_lock(&ifalias_mutex);
1286 new_alias = rcu_replace_pointer(dev->ifalias, new_alias,
1287 mutex_is_locked(&ifalias_mutex));
1288 mutex_unlock(lock: &ifalias_mutex);
1289
1290 if (new_alias)
1291 kfree_rcu(new_alias, rcuhead);
1292
1293 return len;
1294}
1295EXPORT_SYMBOL(dev_set_alias);
1296
1297/**
1298 * dev_get_alias - get ifalias of a device
1299 * @dev: device
1300 * @name: buffer to store name of ifalias
1301 * @len: size of buffer
1302 *
1303 * get ifalias for a device. Caller must make sure dev cannot go
1304 * away, e.g. rcu read lock or own a reference count to device.
1305 */
1306int dev_get_alias(const struct net_device *dev, char *name, size_t len)
1307{
1308 const struct dev_ifalias *alias;
1309 int ret = 0;
1310
1311 rcu_read_lock();
1312 alias = rcu_dereference(dev->ifalias);
1313 if (alias)
1314 ret = snprintf(buf: name, size: len, fmt: "%s", alias->ifalias);
1315 rcu_read_unlock();
1316
1317 return ret;
1318}
1319
1320/**
1321 * netdev_features_change - device changes features
1322 * @dev: device to cause notification
1323 *
1324 * Called to indicate a device has changed features.
1325 */
1326void netdev_features_change(struct net_device *dev)
1327{
1328 call_netdevice_notifiers(val: NETDEV_FEAT_CHANGE, dev);
1329}
1330EXPORT_SYMBOL(netdev_features_change);
1331
1332/**
1333 * netdev_state_change - device changes state
1334 * @dev: device to cause notification
1335 *
1336 * Called to indicate a device has changed state. This function calls
1337 * the notifier chains for netdev_chain and sends a NEWLINK message
1338 * to the routing socket.
1339 */
1340void netdev_state_change(struct net_device *dev)
1341{
1342 if (dev->flags & IFF_UP) {
1343 struct netdev_notifier_change_info change_info = {
1344 .info.dev = dev,
1345 };
1346
1347 call_netdevice_notifiers_info(val: NETDEV_CHANGE,
1348 info: &change_info.info);
1349 rtmsg_ifinfo(RTM_NEWLINK, dev, change: 0, GFP_KERNEL, portid: 0, NULL);
1350 }
1351}
1352EXPORT_SYMBOL(netdev_state_change);
1353
1354/**
1355 * __netdev_notify_peers - notify network peers about existence of @dev,
1356 * to be called when rtnl lock is already held.
1357 * @dev: network device
1358 *
1359 * Generate traffic such that interested network peers are aware of
1360 * @dev, such as by generating a gratuitous ARP. This may be used when
1361 * a device wants to inform the rest of the network about some sort of
1362 * reconfiguration such as a failover event or virtual machine
1363 * migration.
1364 */
1365void __netdev_notify_peers(struct net_device *dev)
1366{
1367 ASSERT_RTNL();
1368 call_netdevice_notifiers(val: NETDEV_NOTIFY_PEERS, dev);
1369 call_netdevice_notifiers(val: NETDEV_RESEND_IGMP, dev);
1370}
1371EXPORT_SYMBOL(__netdev_notify_peers);
1372
1373/**
1374 * netdev_notify_peers - notify network peers about existence of @dev
1375 * @dev: network device
1376 *
1377 * Generate traffic such that interested network peers are aware of
1378 * @dev, such as by generating a gratuitous ARP. This may be used when
1379 * a device wants to inform the rest of the network about some sort of
1380 * reconfiguration such as a failover event or virtual machine
1381 * migration.
1382 */
1383void netdev_notify_peers(struct net_device *dev)
1384{
1385 rtnl_lock();
1386 __netdev_notify_peers(dev);
1387 rtnl_unlock();
1388}
1389EXPORT_SYMBOL(netdev_notify_peers);
1390
1391static int napi_threaded_poll(void *data);
1392
1393static int napi_kthread_create(struct napi_struct *n)
1394{
1395 int err = 0;
1396
1397 /* Create and wake up the kthread once to put it in
1398 * TASK_INTERRUPTIBLE mode to avoid the blocked task
1399 * warning and work with loadavg.
1400 */
1401 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d",
1402 n->dev->name, n->napi_id);
1403 if (IS_ERR(ptr: n->thread)) {
1404 err = PTR_ERR(ptr: n->thread);
1405 pr_err("kthread_run failed with err %d\n", err);
1406 n->thread = NULL;
1407 }
1408
1409 return err;
1410}
1411
1412static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack)
1413{
1414 const struct net_device_ops *ops = dev->netdev_ops;
1415 int ret;
1416
1417 ASSERT_RTNL();
1418 dev_addr_check(dev);
1419
1420 if (!netif_device_present(dev)) {
1421 /* may be detached because parent is runtime-suspended */
1422 if (dev->dev.parent)
1423 pm_runtime_resume(dev: dev->dev.parent);
1424 if (!netif_device_present(dev))
1425 return -ENODEV;
1426 }
1427
1428 /* Block netpoll from trying to do any rx path servicing.
1429 * If we don't do this there is a chance ndo_poll_controller
1430 * or ndo_poll may be running while we open the device
1431 */
1432 netpoll_poll_disable(dev);
1433
1434 ret = call_netdevice_notifiers_extack(val: NETDEV_PRE_UP, dev, extack);
1435 ret = notifier_to_errno(ret);
1436 if (ret)
1437 return ret;
1438
1439 set_bit(nr: __LINK_STATE_START, addr: &dev->state);
1440
1441 if (ops->ndo_validate_addr)
1442 ret = ops->ndo_validate_addr(dev);
1443
1444 if (!ret && ops->ndo_open)
1445 ret = ops->ndo_open(dev);
1446
1447 netpoll_poll_enable(dev);
1448
1449 if (ret)
1450 clear_bit(nr: __LINK_STATE_START, addr: &dev->state);
1451 else {
1452 dev->flags |= IFF_UP;
1453 dev_set_rx_mode(dev);
1454 dev_activate(dev);
1455 add_device_randomness(buf: dev->dev_addr, len: dev->addr_len);
1456 }
1457
1458 return ret;
1459}
1460
1461/**
1462 * dev_open - prepare an interface for use.
1463 * @dev: device to open
1464 * @extack: netlink extended ack
1465 *
1466 * Takes a device from down to up state. The device's private open
1467 * function is invoked and then the multicast lists are loaded. Finally
1468 * the device is moved into the up state and a %NETDEV_UP message is
1469 * sent to the netdev notifier chain.
1470 *
1471 * Calling this function on an active interface is a nop. On a failure
1472 * a negative errno code is returned.
1473 */
1474int dev_open(struct net_device *dev, struct netlink_ext_ack *extack)
1475{
1476 int ret;
1477
1478 if (dev->flags & IFF_UP)
1479 return 0;
1480
1481 ret = __dev_open(dev, extack);
1482 if (ret < 0)
1483 return ret;
1484
1485 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, portid: 0, NULL);
1486 call_netdevice_notifiers(val: NETDEV_UP, dev);
1487
1488 return ret;
1489}
1490EXPORT_SYMBOL(dev_open);
1491
1492static void __dev_close_many(struct list_head *head)
1493{
1494 struct net_device *dev;
1495
1496 ASSERT_RTNL();
1497 might_sleep();
1498
1499 list_for_each_entry(dev, head, close_list) {
1500 /* Temporarily disable netpoll until the interface is down */
1501 netpoll_poll_disable(dev);
1502
1503 call_netdevice_notifiers(val: NETDEV_GOING_DOWN, dev);
1504
1505 clear_bit(nr: __LINK_STATE_START, addr: &dev->state);
1506
1507 /* Synchronize to scheduled poll. We cannot touch poll list, it
1508 * can be even on different cpu. So just clear netif_running().
1509 *
1510 * dev->stop() will invoke napi_disable() on all of it's
1511 * napi_struct instances on this device.
1512 */
1513 smp_mb__after_atomic(); /* Commit netif_running(). */
1514 }
1515
1516 dev_deactivate_many(head);
1517
1518 list_for_each_entry(dev, head, close_list) {
1519 const struct net_device_ops *ops = dev->netdev_ops;
1520
1521 /*
1522 * Call the device specific close. This cannot fail.
1523 * Only if device is UP
1524 *
1525 * We allow it to be called even after a DETACH hot-plug
1526 * event.
1527 */
1528 if (ops->ndo_stop)
1529 ops->ndo_stop(dev);
1530
1531 dev->flags &= ~IFF_UP;
1532 netpoll_poll_enable(dev);
1533 }
1534}
1535
1536static void __dev_close(struct net_device *dev)
1537{
1538 LIST_HEAD(single);
1539
1540 list_add(new: &dev->close_list, head: &single);
1541 __dev_close_many(head: &single);
1542 list_del(entry: &single);
1543}
1544
1545void dev_close_many(struct list_head *head, bool unlink)
1546{
1547 struct net_device *dev, *tmp;
1548
1549 /* Remove the devices that don't need to be closed */
1550 list_for_each_entry_safe(dev, tmp, head, close_list)
1551 if (!(dev->flags & IFF_UP))
1552 list_del_init(entry: &dev->close_list);
1553
1554 __dev_close_many(head);
1555
1556 list_for_each_entry_safe(dev, tmp, head, close_list) {
1557 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, portid: 0, NULL);
1558 call_netdevice_notifiers(val: NETDEV_DOWN, dev);
1559 if (unlink)
1560 list_del_init(entry: &dev->close_list);
1561 }
1562}
1563EXPORT_SYMBOL(dev_close_many);
1564
1565/**
1566 * dev_close - shutdown an interface.
1567 * @dev: device to shutdown
1568 *
1569 * This function moves an active device into down state. A
1570 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1571 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1572 * chain.
1573 */
1574void dev_close(struct net_device *dev)
1575{
1576 if (dev->flags & IFF_UP) {
1577 LIST_HEAD(single);
1578
1579 list_add(new: &dev->close_list, head: &single);
1580 dev_close_many(&single, true);
1581 list_del(entry: &single);
1582 }
1583}
1584EXPORT_SYMBOL(dev_close);
1585
1586
1587/**
1588 * dev_disable_lro - disable Large Receive Offload on a device
1589 * @dev: device
1590 *
1591 * Disable Large Receive Offload (LRO) on a net device. Must be
1592 * called under RTNL. This is needed if received packets may be
1593 * forwarded to another interface.
1594 */
1595void dev_disable_lro(struct net_device *dev)
1596{
1597 struct net_device *lower_dev;
1598 struct list_head *iter;
1599
1600 dev->wanted_features &= ~NETIF_F_LRO;
1601 netdev_update_features(dev);
1602
1603 if (unlikely(dev->features & NETIF_F_LRO))
1604 netdev_WARN(dev, "failed to disable LRO!\n");
1605
1606 netdev_for_each_lower_dev(dev, lower_dev, iter)
1607 dev_disable_lro(dev: lower_dev);
1608}
1609EXPORT_SYMBOL(dev_disable_lro);
1610
1611/**
1612 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device
1613 * @dev: device
1614 *
1615 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be
1616 * called under RTNL. This is needed if Generic XDP is installed on
1617 * the device.
1618 */
1619static void dev_disable_gro_hw(struct net_device *dev)
1620{
1621 dev->wanted_features &= ~NETIF_F_GRO_HW;
1622 netdev_update_features(dev);
1623
1624 if (unlikely(dev->features & NETIF_F_GRO_HW))
1625 netdev_WARN(dev, "failed to disable GRO_HW!\n");
1626}
1627
1628const char *netdev_cmd_to_name(enum netdev_cmd cmd)
1629{
1630#define N(val) \
1631 case NETDEV_##val: \
1632 return "NETDEV_" __stringify(val);
1633 switch (cmd) {
1634 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER)
1635 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE)
1636 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE)
1637 N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN)
1638 N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA)
1639 N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE)
1640 N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN)
1641 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO)
1642 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO)
1643 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE)
1644 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA)
1645 N(XDP_FEAT_CHANGE)
1646 }
1647#undef N
1648 return "UNKNOWN_NETDEV_EVENT";
1649}
1650EXPORT_SYMBOL_GPL(netdev_cmd_to_name);
1651
1652static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1653 struct net_device *dev)
1654{
1655 struct netdev_notifier_info info = {
1656 .dev = dev,
1657 };
1658
1659 return nb->notifier_call(nb, val, &info);
1660}
1661
1662static int call_netdevice_register_notifiers(struct notifier_block *nb,
1663 struct net_device *dev)
1664{
1665 int err;
1666
1667 err = call_netdevice_notifier(nb, val: NETDEV_REGISTER, dev);
1668 err = notifier_to_errno(ret: err);
1669 if (err)
1670 return err;
1671
1672 if (!(dev->flags & IFF_UP))
1673 return 0;
1674
1675 call_netdevice_notifier(nb, val: NETDEV_UP, dev);
1676 return 0;
1677}
1678
1679static void call_netdevice_unregister_notifiers(struct notifier_block *nb,
1680 struct net_device *dev)
1681{
1682 if (dev->flags & IFF_UP) {
1683 call_netdevice_notifier(nb, val: NETDEV_GOING_DOWN,
1684 dev);
1685 call_netdevice_notifier(nb, val: NETDEV_DOWN, dev);
1686 }
1687 call_netdevice_notifier(nb, val: NETDEV_UNREGISTER, dev);
1688}
1689
1690static int call_netdevice_register_net_notifiers(struct notifier_block *nb,
1691 struct net *net)
1692{
1693 struct net_device *dev;
1694 int err;
1695
1696 for_each_netdev(net, dev) {
1697 err = call_netdevice_register_notifiers(nb, dev);
1698 if (err)
1699 goto rollback;
1700 }
1701 return 0;
1702
1703rollback:
1704 for_each_netdev_continue_reverse(net, dev)
1705 call_netdevice_unregister_notifiers(nb, dev);
1706 return err;
1707}
1708
1709static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb,
1710 struct net *net)
1711{
1712 struct net_device *dev;
1713
1714 for_each_netdev(net, dev)
1715 call_netdevice_unregister_notifiers(nb, dev);
1716}
1717
1718static int dev_boot_phase = 1;
1719
1720/**
1721 * register_netdevice_notifier - register a network notifier block
1722 * @nb: notifier
1723 *
1724 * Register a notifier to be called when network device events occur.
1725 * The notifier passed is linked into the kernel structures and must
1726 * not be reused until it has been unregistered. A negative errno code
1727 * is returned on a failure.
1728 *
1729 * When registered all registration and up events are replayed
1730 * to the new notifier to allow device to have a race free
1731 * view of the network device list.
1732 */
1733
1734int register_netdevice_notifier(struct notifier_block *nb)
1735{
1736 struct net *net;
1737 int err;
1738
1739 /* Close race with setup_net() and cleanup_net() */
1740 down_write(sem: &pernet_ops_rwsem);
1741 rtnl_lock();
1742 err = raw_notifier_chain_register(nh: &netdev_chain, nb);
1743 if (err)
1744 goto unlock;
1745 if (dev_boot_phase)
1746 goto unlock;
1747 for_each_net(net) {
1748 err = call_netdevice_register_net_notifiers(nb, net);
1749 if (err)
1750 goto rollback;
1751 }
1752
1753unlock:
1754 rtnl_unlock();
1755 up_write(sem: &pernet_ops_rwsem);
1756 return err;
1757
1758rollback:
1759 for_each_net_continue_reverse(net)
1760 call_netdevice_unregister_net_notifiers(nb, net);
1761
1762 raw_notifier_chain_unregister(nh: &netdev_chain, nb);
1763 goto unlock;
1764}
1765EXPORT_SYMBOL(register_netdevice_notifier);
1766
1767/**
1768 * unregister_netdevice_notifier - unregister a network notifier block
1769 * @nb: notifier
1770 *
1771 * Unregister a notifier previously registered by
1772 * register_netdevice_notifier(). The notifier is unlinked into the
1773 * kernel structures and may then be reused. A negative errno code
1774 * is returned on a failure.
1775 *
1776 * After unregistering unregister and down device events are synthesized
1777 * for all devices on the device list to the removed notifier to remove
1778 * the need for special case cleanup code.
1779 */
1780
1781int unregister_netdevice_notifier(struct notifier_block *nb)
1782{
1783 struct net *net;
1784 int err;
1785
1786 /* Close race with setup_net() and cleanup_net() */
1787 down_write(sem: &pernet_ops_rwsem);
1788 rtnl_lock();
1789 err = raw_notifier_chain_unregister(nh: &netdev_chain, nb);
1790 if (err)
1791 goto unlock;
1792
1793 for_each_net(net)
1794 call_netdevice_unregister_net_notifiers(nb, net);
1795
1796unlock:
1797 rtnl_unlock();
1798 up_write(sem: &pernet_ops_rwsem);
1799 return err;
1800}
1801EXPORT_SYMBOL(unregister_netdevice_notifier);
1802
1803static int __register_netdevice_notifier_net(struct net *net,
1804 struct notifier_block *nb,
1805 bool ignore_call_fail)
1806{
1807 int err;
1808
1809 err = raw_notifier_chain_register(nh: &net->netdev_chain, nb);
1810 if (err)
1811 return err;
1812 if (dev_boot_phase)
1813 return 0;
1814
1815 err = call_netdevice_register_net_notifiers(nb, net);
1816 if (err && !ignore_call_fail)
1817 goto chain_unregister;
1818
1819 return 0;
1820
1821chain_unregister:
1822 raw_notifier_chain_unregister(nh: &net->netdev_chain, nb);
1823 return err;
1824}
1825
1826static int __unregister_netdevice_notifier_net(struct net *net,
1827 struct notifier_block *nb)
1828{
1829 int err;
1830
1831 err = raw_notifier_chain_unregister(nh: &net->netdev_chain, nb);
1832 if (err)
1833 return err;
1834
1835 call_netdevice_unregister_net_notifiers(nb, net);
1836 return 0;
1837}
1838
1839/**
1840 * register_netdevice_notifier_net - register a per-netns network notifier block
1841 * @net: network namespace
1842 * @nb: notifier
1843 *
1844 * Register a notifier to be called when network device events occur.
1845 * The notifier passed is linked into the kernel structures and must
1846 * not be reused until it has been unregistered. A negative errno code
1847 * is returned on a failure.
1848 *
1849 * When registered all registration and up events are replayed
1850 * to the new notifier to allow device to have a race free
1851 * view of the network device list.
1852 */
1853
1854int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb)
1855{
1856 int err;
1857
1858 rtnl_lock();
1859 err = __register_netdevice_notifier_net(net, nb, ignore_call_fail: false);
1860 rtnl_unlock();
1861 return err;
1862}
1863EXPORT_SYMBOL(register_netdevice_notifier_net);
1864
1865/**
1866 * unregister_netdevice_notifier_net - unregister a per-netns
1867 * network notifier block
1868 * @net: network namespace
1869 * @nb: notifier
1870 *
1871 * Unregister a notifier previously registered by
1872 * register_netdevice_notifier_net(). The notifier is unlinked from the
1873 * kernel structures and may then be reused. A negative errno code
1874 * is returned on a failure.
1875 *
1876 * After unregistering unregister and down device events are synthesized
1877 * for all devices on the device list to the removed notifier to remove
1878 * the need for special case cleanup code.
1879 */
1880
1881int unregister_netdevice_notifier_net(struct net *net,
1882 struct notifier_block *nb)
1883{
1884 int err;
1885
1886 rtnl_lock();
1887 err = __unregister_netdevice_notifier_net(net, nb);
1888 rtnl_unlock();
1889 return err;
1890}
1891EXPORT_SYMBOL(unregister_netdevice_notifier_net);
1892
1893static void __move_netdevice_notifier_net(struct net *src_net,
1894 struct net *dst_net,
1895 struct notifier_block *nb)
1896{
1897 __unregister_netdevice_notifier_net(net: src_net, nb);
1898 __register_netdevice_notifier_net(net: dst_net, nb, ignore_call_fail: true);
1899}
1900
1901int register_netdevice_notifier_dev_net(struct net_device *dev,
1902 struct notifier_block *nb,
1903 struct netdev_net_notifier *nn)
1904{
1905 int err;
1906
1907 rtnl_lock();
1908 err = __register_netdevice_notifier_net(net: dev_net(dev), nb, ignore_call_fail: false);
1909 if (!err) {
1910 nn->nb = nb;
1911 list_add(new: &nn->list, head: &dev->net_notifier_list);
1912 }
1913 rtnl_unlock();
1914 return err;
1915}
1916EXPORT_SYMBOL(register_netdevice_notifier_dev_net);
1917
1918int unregister_netdevice_notifier_dev_net(struct net_device *dev,
1919 struct notifier_block *nb,
1920 struct netdev_net_notifier *nn)
1921{
1922 int err;
1923
1924 rtnl_lock();
1925 list_del(entry: &nn->list);
1926 err = __unregister_netdevice_notifier_net(net: dev_net(dev), nb);
1927 rtnl_unlock();
1928 return err;
1929}
1930EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net);
1931
1932static void move_netdevice_notifiers_dev_net(struct net_device *dev,
1933 struct net *net)
1934{
1935 struct netdev_net_notifier *nn;
1936
1937 list_for_each_entry(nn, &dev->net_notifier_list, list)
1938 __move_netdevice_notifier_net(src_net: dev_net(dev), dst_net: net, nb: nn->nb);
1939}
1940
1941/**
1942 * call_netdevice_notifiers_info - call all network notifier blocks
1943 * @val: value passed unmodified to notifier function
1944 * @info: notifier information data
1945 *
1946 * Call all network notifier blocks. Parameters and return value
1947 * are as for raw_notifier_call_chain().
1948 */
1949
1950int call_netdevice_notifiers_info(unsigned long val,
1951 struct netdev_notifier_info *info)
1952{
1953 struct net *net = dev_net(dev: info->dev);
1954 int ret;
1955
1956 ASSERT_RTNL();
1957
1958 /* Run per-netns notifier block chain first, then run the global one.
1959 * Hopefully, one day, the global one is going to be removed after
1960 * all notifier block registrators get converted to be per-netns.
1961 */
1962 ret = raw_notifier_call_chain(nh: &net->netdev_chain, val, v: info);
1963 if (ret & NOTIFY_STOP_MASK)
1964 return ret;
1965 return raw_notifier_call_chain(nh: &netdev_chain, val, v: info);
1966}
1967
1968/**
1969 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks
1970 * for and rollback on error
1971 * @val_up: value passed unmodified to notifier function
1972 * @val_down: value passed unmodified to the notifier function when
1973 * recovering from an error on @val_up
1974 * @info: notifier information data
1975 *
1976 * Call all per-netns network notifier blocks, but not notifier blocks on
1977 * the global notifier chain. Parameters and return value are as for
1978 * raw_notifier_call_chain_robust().
1979 */
1980
1981static int
1982call_netdevice_notifiers_info_robust(unsigned long val_up,
1983 unsigned long val_down,
1984 struct netdev_notifier_info *info)
1985{
1986 struct net *net = dev_net(dev: info->dev);
1987
1988 ASSERT_RTNL();
1989
1990 return raw_notifier_call_chain_robust(nh: &net->netdev_chain,
1991 val_up, val_down, v: info);
1992}
1993
1994static int call_netdevice_notifiers_extack(unsigned long val,
1995 struct net_device *dev,
1996 struct netlink_ext_ack *extack)
1997{
1998 struct netdev_notifier_info info = {
1999 .dev = dev,
2000 .extack = extack,
2001 };
2002
2003 return call_netdevice_notifiers_info(val, info: &info);
2004}
2005
2006/**
2007 * call_netdevice_notifiers - call all network notifier blocks
2008 * @val: value passed unmodified to notifier function
2009 * @dev: net_device pointer passed unmodified to notifier function
2010 *
2011 * Call all network notifier blocks. Parameters and return value
2012 * are as for raw_notifier_call_chain().
2013 */
2014
2015int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
2016{
2017 return call_netdevice_notifiers_extack(val, dev, NULL);
2018}
2019EXPORT_SYMBOL(call_netdevice_notifiers);
2020
2021/**
2022 * call_netdevice_notifiers_mtu - call all network notifier blocks
2023 * @val: value passed unmodified to notifier function
2024 * @dev: net_device pointer passed unmodified to notifier function
2025 * @arg: additional u32 argument passed to the notifier function
2026 *
2027 * Call all network notifier blocks. Parameters and return value
2028 * are as for raw_notifier_call_chain().
2029 */
2030static int call_netdevice_notifiers_mtu(unsigned long val,
2031 struct net_device *dev, u32 arg)
2032{
2033 struct netdev_notifier_info_ext info = {
2034 .info.dev = dev,
2035 .ext.mtu = arg,
2036 };
2037
2038 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0);
2039
2040 return call_netdevice_notifiers_info(val, info: &info.info);
2041}
2042
2043#ifdef CONFIG_NET_INGRESS
2044static DEFINE_STATIC_KEY_FALSE(ingress_needed_key);
2045
2046void net_inc_ingress_queue(void)
2047{
2048 static_branch_inc(&ingress_needed_key);
2049}
2050EXPORT_SYMBOL_GPL(net_inc_ingress_queue);
2051
2052void net_dec_ingress_queue(void)
2053{
2054 static_branch_dec(&ingress_needed_key);
2055}
2056EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
2057#endif
2058
2059#ifdef CONFIG_NET_EGRESS
2060static DEFINE_STATIC_KEY_FALSE(egress_needed_key);
2061
2062void net_inc_egress_queue(void)
2063{
2064 static_branch_inc(&egress_needed_key);
2065}
2066EXPORT_SYMBOL_GPL(net_inc_egress_queue);
2067
2068void net_dec_egress_queue(void)
2069{
2070 static_branch_dec(&egress_needed_key);
2071}
2072EXPORT_SYMBOL_GPL(net_dec_egress_queue);
2073#endif
2074
2075DEFINE_STATIC_KEY_FALSE(netstamp_needed_key);
2076EXPORT_SYMBOL(netstamp_needed_key);
2077#ifdef CONFIG_JUMP_LABEL
2078static atomic_t netstamp_needed_deferred;
2079static atomic_t netstamp_wanted;
2080static void netstamp_clear(struct work_struct *work)
2081{
2082 int deferred = atomic_xchg(v: &netstamp_needed_deferred, new: 0);
2083 int wanted;
2084
2085 wanted = atomic_add_return(i: deferred, v: &netstamp_wanted);
2086 if (wanted > 0)
2087 static_branch_enable(&netstamp_needed_key);
2088 else
2089 static_branch_disable(&netstamp_needed_key);
2090}
2091static DECLARE_WORK(netstamp_work, netstamp_clear);
2092#endif
2093
2094void net_enable_timestamp(void)
2095{
2096#ifdef CONFIG_JUMP_LABEL
2097 int wanted = atomic_read(v: &netstamp_wanted);
2098
2099 while (wanted > 0) {
2100 if (atomic_try_cmpxchg(v: &netstamp_wanted, old: &wanted, new: wanted + 1))
2101 return;
2102 }
2103 atomic_inc(v: &netstamp_needed_deferred);
2104 schedule_work(work: &netstamp_work);
2105#else
2106 static_branch_inc(&netstamp_needed_key);
2107#endif
2108}
2109EXPORT_SYMBOL(net_enable_timestamp);
2110
2111void net_disable_timestamp(void)
2112{
2113#ifdef CONFIG_JUMP_LABEL
2114 int wanted = atomic_read(v: &netstamp_wanted);
2115
2116 while (wanted > 1) {
2117 if (atomic_try_cmpxchg(v: &netstamp_wanted, old: &wanted, new: wanted - 1))
2118 return;
2119 }
2120 atomic_dec(v: &netstamp_needed_deferred);
2121 schedule_work(work: &netstamp_work);
2122#else
2123 static_branch_dec(&netstamp_needed_key);
2124#endif
2125}
2126EXPORT_SYMBOL(net_disable_timestamp);
2127
2128static inline void net_timestamp_set(struct sk_buff *skb)
2129{
2130 skb->tstamp = 0;
2131 skb->mono_delivery_time = 0;
2132 if (static_branch_unlikely(&netstamp_needed_key))
2133 skb->tstamp = ktime_get_real();
2134}
2135
2136#define net_timestamp_check(COND, SKB) \
2137 if (static_branch_unlikely(&netstamp_needed_key)) { \
2138 if ((COND) && !(SKB)->tstamp) \
2139 (SKB)->tstamp = ktime_get_real(); \
2140 } \
2141
2142bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb)
2143{
2144 return __is_skb_forwardable(dev, skb, check_mtu: true);
2145}
2146EXPORT_SYMBOL_GPL(is_skb_forwardable);
2147
2148static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb,
2149 bool check_mtu)
2150{
2151 int ret = ____dev_forward_skb(dev, skb, check_mtu);
2152
2153 if (likely(!ret)) {
2154 skb->protocol = eth_type_trans(skb, dev);
2155 skb_postpull_rcsum(skb, start: eth_hdr(skb), ETH_HLEN);
2156 }
2157
2158 return ret;
2159}
2160
2161int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
2162{
2163 return __dev_forward_skb2(dev, skb, check_mtu: true);
2164}
2165EXPORT_SYMBOL_GPL(__dev_forward_skb);
2166
2167/**
2168 * dev_forward_skb - loopback an skb to another netif
2169 *
2170 * @dev: destination network device
2171 * @skb: buffer to forward
2172 *
2173 * return values:
2174 * NET_RX_SUCCESS (no congestion)
2175 * NET_RX_DROP (packet was dropped, but freed)
2176 *
2177 * dev_forward_skb can be used for injecting an skb from the
2178 * start_xmit function of one device into the receive queue
2179 * of another device.
2180 *
2181 * The receiving device may be in another namespace, so
2182 * we have to clear all information in the skb that could
2183 * impact namespace isolation.
2184 */
2185int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
2186{
2187 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
2188}
2189EXPORT_SYMBOL_GPL(dev_forward_skb);
2190
2191int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb)
2192{
2193 return __dev_forward_skb2(dev, skb, check_mtu: false) ?: netif_rx_internal(skb);
2194}
2195
2196static inline int deliver_skb(struct sk_buff *skb,
2197 struct packet_type *pt_prev,
2198 struct net_device *orig_dev)
2199{
2200 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
2201 return -ENOMEM;
2202 refcount_inc(r: &skb->users);
2203 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
2204}
2205
2206static inline void deliver_ptype_list_skb(struct sk_buff *skb,
2207 struct packet_type **pt,
2208 struct net_device *orig_dev,
2209 __be16 type,
2210 struct list_head *ptype_list)
2211{
2212 struct packet_type *ptype, *pt_prev = *pt;
2213
2214 list_for_each_entry_rcu(ptype, ptype_list, list) {
2215 if (ptype->type != type)
2216 continue;
2217 if (pt_prev)
2218 deliver_skb(skb, pt_prev, orig_dev);
2219 pt_prev = ptype;
2220 }
2221 *pt = pt_prev;
2222}
2223
2224static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
2225{
2226 if (!ptype->af_packet_priv || !skb->sk)
2227 return false;
2228
2229 if (ptype->id_match)
2230 return ptype->id_match(ptype, skb->sk);
2231 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
2232 return true;
2233
2234 return false;
2235}
2236
2237/**
2238 * dev_nit_active - return true if any network interface taps are in use
2239 *
2240 * @dev: network device to check for the presence of taps
2241 */
2242bool dev_nit_active(struct net_device *dev)
2243{
2244 return !list_empty(head: &ptype_all) || !list_empty(head: &dev->ptype_all);
2245}
2246EXPORT_SYMBOL_GPL(dev_nit_active);
2247
2248/*
2249 * Support routine. Sends outgoing frames to any network
2250 * taps currently in use.
2251 */
2252
2253void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
2254{
2255 struct packet_type *ptype;
2256 struct sk_buff *skb2 = NULL;
2257 struct packet_type *pt_prev = NULL;
2258 struct list_head *ptype_list = &ptype_all;
2259
2260 rcu_read_lock();
2261again:
2262 list_for_each_entry_rcu(ptype, ptype_list, list) {
2263 if (ptype->ignore_outgoing)
2264 continue;
2265
2266 /* Never send packets back to the socket
2267 * they originated from - MvS (miquels@drinkel.ow.org)
2268 */
2269 if (skb_loop_sk(ptype, skb))
2270 continue;
2271
2272 if (pt_prev) {
2273 deliver_skb(skb: skb2, pt_prev, orig_dev: skb->dev);
2274 pt_prev = ptype;
2275 continue;
2276 }
2277
2278 /* need to clone skb, done only once */
2279 skb2 = skb_clone(skb, GFP_ATOMIC);
2280 if (!skb2)
2281 goto out_unlock;
2282
2283 net_timestamp_set(skb: skb2);
2284
2285 /* skb->nh should be correctly
2286 * set by sender, so that the second statement is
2287 * just protection against buggy protocols.
2288 */
2289 skb_reset_mac_header(skb: skb2);
2290
2291 if (skb_network_header(skb: skb2) < skb2->data ||
2292 skb_network_header(skb: skb2) > skb_tail_pointer(skb: skb2)) {
2293 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
2294 ntohs(skb2->protocol),
2295 dev->name);
2296 skb_reset_network_header(skb: skb2);
2297 }
2298
2299 skb2->transport_header = skb2->network_header;
2300 skb2->pkt_type = PACKET_OUTGOING;
2301 pt_prev = ptype;
2302 }
2303
2304 if (ptype_list == &ptype_all) {
2305 ptype_list = &dev->ptype_all;
2306 goto again;
2307 }
2308out_unlock:
2309 if (pt_prev) {
2310 if (!skb_orphan_frags_rx(skb: skb2, GFP_ATOMIC))
2311 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
2312 else
2313 kfree_skb(skb: skb2);
2314 }
2315 rcu_read_unlock();
2316}
2317EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);
2318
2319/**
2320 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
2321 * @dev: Network device
2322 * @txq: number of queues available
2323 *
2324 * If real_num_tx_queues is changed the tc mappings may no longer be
2325 * valid. To resolve this verify the tc mapping remains valid and if
2326 * not NULL the mapping. With no priorities mapping to this
2327 * offset/count pair it will no longer be used. In the worst case TC0
2328 * is invalid nothing can be done so disable priority mappings. If is
2329 * expected that drivers will fix this mapping if they can before
2330 * calling netif_set_real_num_tx_queues.
2331 */
2332static void netif_setup_tc(struct net_device *dev, unsigned int txq)
2333{
2334 int i;
2335 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
2336
2337 /* If TC0 is invalidated disable TC mapping */
2338 if (tc->offset + tc->count > txq) {
2339 netdev_warn(dev, format: "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
2340 dev->num_tc = 0;
2341 return;
2342 }
2343
2344 /* Invalidated prio to tc mappings set to TC0 */
2345 for (i = 1; i < TC_BITMASK + 1; i++) {
2346 int q = netdev_get_prio_tc_map(dev, prio: i);
2347
2348 tc = &dev->tc_to_txq[q];
2349 if (tc->offset + tc->count > txq) {
2350 netdev_warn(dev, format: "Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
2351 i, q);
2352 netdev_set_prio_tc_map(dev, prio: i, tc: 0);
2353 }
2354 }
2355}
2356
2357int netdev_txq_to_tc(struct net_device *dev, unsigned int txq)
2358{
2359 if (dev->num_tc) {
2360 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
2361 int i;
2362
2363 /* walk through the TCs and see if it falls into any of them */
2364 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) {
2365 if ((txq - tc->offset) < tc->count)
2366 return i;
2367 }
2368
2369 /* didn't find it, just return -1 to indicate no match */
2370 return -1;
2371 }
2372
2373 return 0;
2374}
2375EXPORT_SYMBOL(netdev_txq_to_tc);
2376
2377#ifdef CONFIG_XPS
2378static struct static_key xps_needed __read_mostly;
2379static struct static_key xps_rxqs_needed __read_mostly;
2380static DEFINE_MUTEX(xps_map_mutex);
2381#define xmap_dereference(P) \
2382 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
2383
2384static bool remove_xps_queue(struct xps_dev_maps *dev_maps,
2385 struct xps_dev_maps *old_maps, int tci, u16 index)
2386{
2387 struct xps_map *map = NULL;
2388 int pos;
2389
2390 map = xmap_dereference(dev_maps->attr_map[tci]);
2391 if (!map)
2392 return false;
2393
2394 for (pos = map->len; pos--;) {
2395 if (map->queues[pos] != index)
2396 continue;
2397
2398 if (map->len > 1) {
2399 map->queues[pos] = map->queues[--map->len];
2400 break;
2401 }
2402
2403 if (old_maps)
2404 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL);
2405 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL);
2406 kfree_rcu(map, rcu);
2407 return false;
2408 }
2409
2410 return true;
2411}
2412
2413static bool remove_xps_queue_cpu(struct net_device *dev,
2414 struct xps_dev_maps *dev_maps,
2415 int cpu, u16 offset, u16 count)
2416{
2417 int num_tc = dev_maps->num_tc;
2418 bool active = false;
2419 int tci;
2420
2421 for (tci = cpu * num_tc; num_tc--; tci++) {
2422 int i, j;
2423
2424 for (i = count, j = offset; i--; j++) {
2425 if (!remove_xps_queue(dev_maps, NULL, tci, index: j))
2426 break;
2427 }
2428
2429 active |= i < 0;
2430 }
2431
2432 return active;
2433}
2434
2435static void reset_xps_maps(struct net_device *dev,
2436 struct xps_dev_maps *dev_maps,
2437 enum xps_map_type type)
2438{
2439 static_key_slow_dec_cpuslocked(key: &xps_needed);
2440 if (type == XPS_RXQS)
2441 static_key_slow_dec_cpuslocked(key: &xps_rxqs_needed);
2442
2443 RCU_INIT_POINTER(dev->xps_maps[type], NULL);
2444
2445 kfree_rcu(dev_maps, rcu);
2446}
2447
2448static void clean_xps_maps(struct net_device *dev, enum xps_map_type type,
2449 u16 offset, u16 count)
2450{
2451 struct xps_dev_maps *dev_maps;
2452 bool active = false;
2453 int i, j;
2454
2455 dev_maps = xmap_dereference(dev->xps_maps[type]);
2456 if (!dev_maps)
2457 return;
2458
2459 for (j = 0; j < dev_maps->nr_ids; j++)
2460 active |= remove_xps_queue_cpu(dev, dev_maps, cpu: j, offset, count);
2461 if (!active)
2462 reset_xps_maps(dev, dev_maps, type);
2463
2464 if (type == XPS_CPUS) {
2465 for (i = offset + (count - 1); count--; i--)
2466 netdev_queue_numa_node_write(
2467 q: netdev_get_tx_queue(dev, index: i), NUMA_NO_NODE);
2468 }
2469}
2470
2471static void netif_reset_xps_queues(struct net_device *dev, u16 offset,
2472 u16 count)
2473{
2474 if (!static_key_false(key: &xps_needed))
2475 return;
2476
2477 cpus_read_lock();
2478 mutex_lock(&xps_map_mutex);
2479
2480 if (static_key_false(key: &xps_rxqs_needed))
2481 clean_xps_maps(dev, type: XPS_RXQS, offset, count);
2482
2483 clean_xps_maps(dev, type: XPS_CPUS, offset, count);
2484
2485 mutex_unlock(lock: &xps_map_mutex);
2486 cpus_read_unlock();
2487}
2488
2489static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
2490{
2491 netif_reset_xps_queues(dev, offset: index, count: dev->num_tx_queues - index);
2492}
2493
2494static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index,
2495 u16 index, bool is_rxqs_map)
2496{
2497 struct xps_map *new_map;
2498 int alloc_len = XPS_MIN_MAP_ALLOC;
2499 int i, pos;
2500
2501 for (pos = 0; map && pos < map->len; pos++) {
2502 if (map->queues[pos] != index)
2503 continue;
2504 return map;
2505 }
2506
2507 /* Need to add tx-queue to this CPU's/rx-queue's existing map */
2508 if (map) {
2509 if (pos < map->alloc_len)
2510 return map;
2511
2512 alloc_len = map->alloc_len * 2;
2513 }
2514
2515 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's
2516 * map
2517 */
2518 if (is_rxqs_map)
2519 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL);
2520 else
2521 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
2522 cpu_to_node(cpu: attr_index));
2523 if (!new_map)
2524 return NULL;
2525
2526 for (i = 0; i < pos; i++)
2527 new_map->queues[i] = map->queues[i];
2528 new_map->alloc_len = alloc_len;
2529 new_map->len = pos;
2530
2531 return new_map;
2532}
2533
2534/* Copy xps maps at a given index */
2535static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps,
2536 struct xps_dev_maps *new_dev_maps, int index,
2537 int tc, bool skip_tc)
2538{
2539 int i, tci = index * dev_maps->num_tc;
2540 struct xps_map *map;
2541
2542 /* copy maps belonging to foreign traffic classes */
2543 for (i = 0; i < dev_maps->num_tc; i++, tci++) {
2544 if (i == tc && skip_tc)
2545 continue;
2546
2547 /* fill in the new device map from the old device map */
2548 map = xmap_dereference(dev_maps->attr_map[tci]);
2549 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
2550 }
2551}
2552
2553/* Must be called under cpus_read_lock */
2554int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask,
2555 u16 index, enum xps_map_type type)
2556{
2557 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL;
2558 const unsigned long *online_mask = NULL;
2559 bool active = false, copy = false;
2560 int i, j, tci, numa_node_id = -2;
2561 int maps_sz, num_tc = 1, tc = 0;
2562 struct xps_map *map, *new_map;
2563 unsigned int nr_ids;
2564
2565 WARN_ON_ONCE(index >= dev->num_tx_queues);
2566
2567 if (dev->num_tc) {
2568 /* Do not allow XPS on subordinate device directly */
2569 num_tc = dev->num_tc;
2570 if (num_tc < 0)
2571 return -EINVAL;
2572
2573 /* If queue belongs to subordinate dev use its map */
2574 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
2575
2576 tc = netdev_txq_to_tc(dev, index);
2577 if (tc < 0)
2578 return -EINVAL;
2579 }
2580
2581 mutex_lock(&xps_map_mutex);
2582
2583 dev_maps = xmap_dereference(dev->xps_maps[type]);
2584 if (type == XPS_RXQS) {
2585 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues);
2586 nr_ids = dev->num_rx_queues;
2587 } else {
2588 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc);
2589 if (num_possible_cpus() > 1)
2590 online_mask = cpumask_bits(cpu_online_mask);
2591 nr_ids = nr_cpu_ids;
2592 }
2593
2594 if (maps_sz < L1_CACHE_BYTES)
2595 maps_sz = L1_CACHE_BYTES;
2596
2597 /* The old dev_maps could be larger or smaller than the one we're
2598 * setting up now, as dev->num_tc or nr_ids could have been updated in
2599 * between. We could try to be smart, but let's be safe instead and only
2600 * copy foreign traffic classes if the two map sizes match.
2601 */
2602 if (dev_maps &&
2603 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids)
2604 copy = true;
2605
2606 /* allocate memory for queue storage */
2607 for (j = -1; j = netif_attrmask_next_and(n: j, src1p: online_mask, src2p: mask, nr_bits: nr_ids),
2608 j < nr_ids;) {
2609 if (!new_dev_maps) {
2610 new_dev_maps = kzalloc(size: maps_sz, GFP_KERNEL);
2611 if (!new_dev_maps) {
2612 mutex_unlock(lock: &xps_map_mutex);
2613 return -ENOMEM;
2614 }
2615
2616 new_dev_maps->nr_ids = nr_ids;
2617 new_dev_maps->num_tc = num_tc;
2618 }
2619
2620 tci = j * num_tc + tc;
2621 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL;
2622
2623 map = expand_xps_map(map, attr_index: j, index, is_rxqs_map: type == XPS_RXQS);
2624 if (!map)
2625 goto error;
2626
2627 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
2628 }
2629
2630 if (!new_dev_maps)
2631 goto out_no_new_maps;
2632
2633 if (!dev_maps) {
2634 /* Increment static keys at most once per type */
2635 static_key_slow_inc_cpuslocked(key: &xps_needed);
2636 if (type == XPS_RXQS)
2637 static_key_slow_inc_cpuslocked(key: &xps_rxqs_needed);
2638 }
2639
2640 for (j = 0; j < nr_ids; j++) {
2641 bool skip_tc = false;
2642
2643 tci = j * num_tc + tc;
2644 if (netif_attr_test_mask(j, mask, nr_bits: nr_ids) &&
2645 netif_attr_test_online(j, online_mask, nr_bits: nr_ids)) {
2646 /* add tx-queue to CPU/rx-queue maps */
2647 int pos = 0;
2648
2649 skip_tc = true;
2650
2651 map = xmap_dereference(new_dev_maps->attr_map[tci]);
2652 while ((pos < map->len) && (map->queues[pos] != index))
2653 pos++;
2654
2655 if (pos == map->len)
2656 map->queues[map->len++] = index;
2657#ifdef CONFIG_NUMA
2658 if (type == XPS_CPUS) {
2659 if (numa_node_id == -2)
2660 numa_node_id = cpu_to_node(cpu: j);
2661 else if (numa_node_id != cpu_to_node(cpu: j))
2662 numa_node_id = -1;
2663 }
2664#endif
2665 }
2666
2667 if (copy)
2668 xps_copy_dev_maps(dev_maps, new_dev_maps, index: j, tc,
2669 skip_tc);
2670 }
2671
2672 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps);
2673
2674 /* Cleanup old maps */
2675 if (!dev_maps)
2676 goto out_no_old_maps;
2677
2678 for (j = 0; j < dev_maps->nr_ids; j++) {
2679 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) {
2680 map = xmap_dereference(dev_maps->attr_map[tci]);
2681 if (!map)
2682 continue;
2683
2684 if (copy) {
2685 new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
2686 if (map == new_map)
2687 continue;
2688 }
2689
2690 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL);
2691 kfree_rcu(map, rcu);
2692 }
2693 }
2694
2695 old_dev_maps = dev_maps;
2696
2697out_no_old_maps:
2698 dev_maps = new_dev_maps;
2699 active = true;
2700
2701out_no_new_maps:
2702 if (type == XPS_CPUS)
2703 /* update Tx queue numa node */
2704 netdev_queue_numa_node_write(q: netdev_get_tx_queue(dev, index),
2705 node: (numa_node_id >= 0) ?
2706 numa_node_id : NUMA_NO_NODE);
2707
2708 if (!dev_maps)
2709 goto out_no_maps;
2710
2711 /* removes tx-queue from unused CPUs/rx-queues */
2712 for (j = 0; j < dev_maps->nr_ids; j++) {
2713 tci = j * dev_maps->num_tc;
2714
2715 for (i = 0; i < dev_maps->num_tc; i++, tci++) {
2716 if (i == tc &&
2717 netif_attr_test_mask(j, mask, nr_bits: dev_maps->nr_ids) &&
2718 netif_attr_test_online(j, online_mask, nr_bits: dev_maps->nr_ids))
2719 continue;
2720
2721 active |= remove_xps_queue(dev_maps,
2722 old_maps: copy ? old_dev_maps : NULL,
2723 tci, index);
2724 }
2725 }
2726
2727 if (old_dev_maps)
2728 kfree_rcu(old_dev_maps, rcu);
2729
2730 /* free map if not active */
2731 if (!active)
2732 reset_xps_maps(dev, dev_maps, type);
2733
2734out_no_maps:
2735 mutex_unlock(lock: &xps_map_mutex);
2736
2737 return 0;
2738error:
2739 /* remove any maps that we added */
2740 for (j = 0; j < nr_ids; j++) {
2741 for (i = num_tc, tci = j * num_tc; i--; tci++) {
2742 new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
2743 map = copy ?
2744 xmap_dereference(dev_maps->attr_map[tci]) :
2745 NULL;
2746 if (new_map && new_map != map)
2747 kfree(objp: new_map);
2748 }
2749 }
2750
2751 mutex_unlock(lock: &xps_map_mutex);
2752
2753 kfree(objp: new_dev_maps);
2754 return -ENOMEM;
2755}
2756EXPORT_SYMBOL_GPL(__netif_set_xps_queue);
2757
2758int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
2759 u16 index)
2760{
2761 int ret;
2762
2763 cpus_read_lock();
2764 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS);
2765 cpus_read_unlock();
2766
2767 return ret;
2768}
2769EXPORT_SYMBOL(netif_set_xps_queue);
2770
2771#endif
2772static void netdev_unbind_all_sb_channels(struct net_device *dev)
2773{
2774 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
2775
2776 /* Unbind any subordinate channels */
2777 while (txq-- != &dev->_tx[0]) {
2778 if (txq->sb_dev)
2779 netdev_unbind_sb_channel(dev, sb_dev: txq->sb_dev);
2780 }
2781}
2782
2783void netdev_reset_tc(struct net_device *dev)
2784{
2785#ifdef CONFIG_XPS
2786 netif_reset_xps_queues_gt(dev, index: 0);
2787#endif
2788 netdev_unbind_all_sb_channels(dev);
2789
2790 /* Reset TC configuration of device */
2791 dev->num_tc = 0;
2792 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq));
2793 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map));
2794}
2795EXPORT_SYMBOL(netdev_reset_tc);
2796
2797int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset)
2798{
2799 if (tc >= dev->num_tc)
2800 return -EINVAL;
2801
2802#ifdef CONFIG_XPS
2803 netif_reset_xps_queues(dev, offset, count);
2804#endif
2805 dev->tc_to_txq[tc].count = count;
2806 dev->tc_to_txq[tc].offset = offset;
2807 return 0;
2808}
2809EXPORT_SYMBOL(netdev_set_tc_queue);
2810
2811int netdev_set_num_tc(struct net_device *dev, u8 num_tc)
2812{
2813 if (num_tc > TC_MAX_QUEUE)
2814 return -EINVAL;
2815
2816#ifdef CONFIG_XPS
2817 netif_reset_xps_queues_gt(dev, index: 0);
2818#endif
2819 netdev_unbind_all_sb_channels(dev);
2820
2821 dev->num_tc = num_tc;
2822 return 0;
2823}
2824EXPORT_SYMBOL(netdev_set_num_tc);
2825
2826void netdev_unbind_sb_channel(struct net_device *dev,
2827 struct net_device *sb_dev)
2828{
2829 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
2830
2831#ifdef CONFIG_XPS
2832 netif_reset_xps_queues_gt(dev: sb_dev, index: 0);
2833#endif
2834 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq));
2835 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map));
2836
2837 while (txq-- != &dev->_tx[0]) {
2838 if (txq->sb_dev == sb_dev)
2839 txq->sb_dev = NULL;
2840 }
2841}
2842EXPORT_SYMBOL(netdev_unbind_sb_channel);
2843
2844int netdev_bind_sb_channel_queue(struct net_device *dev,
2845 struct net_device *sb_dev,
2846 u8 tc, u16 count, u16 offset)
2847{
2848 /* Make certain the sb_dev and dev are already configured */
2849 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc)
2850 return -EINVAL;
2851
2852 /* We cannot hand out queues we don't have */
2853 if ((offset + count) > dev->real_num_tx_queues)
2854 return -EINVAL;
2855
2856 /* Record the mapping */
2857 sb_dev->tc_to_txq[tc].count = count;
2858 sb_dev->tc_to_txq[tc].offset = offset;
2859
2860 /* Provide a way for Tx queue to find the tc_to_txq map or
2861 * XPS map for itself.
2862 */
2863 while (count--)
2864 netdev_get_tx_queue(dev, index: count + offset)->sb_dev = sb_dev;
2865
2866 return 0;
2867}
2868EXPORT_SYMBOL(netdev_bind_sb_channel_queue);
2869
2870int netdev_set_sb_channel(struct net_device *dev, u16 channel)
2871{
2872 /* Do not use a multiqueue device to represent a subordinate channel */
2873 if (netif_is_multiqueue(dev))
2874 return -ENODEV;
2875
2876 /* We allow channels 1 - 32767 to be used for subordinate channels.
2877 * Channel 0 is meant to be "native" mode and used only to represent
2878 * the main root device. We allow writing 0 to reset the device back
2879 * to normal mode after being used as a subordinate channel.
2880 */
2881 if (channel > S16_MAX)
2882 return -EINVAL;
2883
2884 dev->num_tc = -channel;
2885
2886 return 0;
2887}
2888EXPORT_SYMBOL(netdev_set_sb_channel);
2889
2890/*
2891 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2892 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed.
2893 */
2894int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2895{
2896 bool disabling;
2897 int rc;
2898
2899 disabling = txq < dev->real_num_tx_queues;
2900
2901 if (txq < 1 || txq > dev->num_tx_queues)
2902 return -EINVAL;
2903
2904 if (dev->reg_state == NETREG_REGISTERED ||
2905 dev->reg_state == NETREG_UNREGISTERING) {
2906 ASSERT_RTNL();
2907
2908 rc = netdev_queue_update_kobjects(net: dev, old_num: dev->real_num_tx_queues,
2909 new_num: txq);
2910 if (rc)
2911 return rc;
2912
2913 if (dev->num_tc)
2914 netif_setup_tc(dev, txq);
2915
2916 dev_qdisc_change_real_num_tx(dev, new_real_tx: txq);
2917
2918 dev->real_num_tx_queues = txq;
2919
2920 if (disabling) {
2921 synchronize_net();
2922 qdisc_reset_all_tx_gt(dev, i: txq);
2923#ifdef CONFIG_XPS
2924 netif_reset_xps_queues_gt(dev, index: txq);
2925#endif
2926 }
2927 } else {
2928 dev->real_num_tx_queues = txq;
2929 }
2930
2931 return 0;
2932}
2933EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2934
2935#ifdef CONFIG_SYSFS
2936/**
2937 * netif_set_real_num_rx_queues - set actual number of RX queues used
2938 * @dev: Network device
2939 * @rxq: Actual number of RX queues
2940 *
2941 * This must be called either with the rtnl_lock held or before
2942 * registration of the net device. Returns 0 on success, or a
2943 * negative error code. If called before registration, it always
2944 * succeeds.
2945 */
2946int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2947{
2948 int rc;
2949
2950 if (rxq < 1 || rxq > dev->num_rx_queues)
2951 return -EINVAL;
2952
2953 if (dev->reg_state == NETREG_REGISTERED) {
2954 ASSERT_RTNL();
2955
2956 rc = net_rx_queue_update_kobjects(dev, old_num: dev->real_num_rx_queues,
2957 new_num: rxq);
2958 if (rc)
2959 return rc;
2960 }
2961
2962 dev->real_num_rx_queues = rxq;
2963 return 0;
2964}
2965EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2966#endif
2967
2968/**
2969 * netif_set_real_num_queues - set actual number of RX and TX queues used
2970 * @dev: Network device
2971 * @txq: Actual number of TX queues
2972 * @rxq: Actual number of RX queues
2973 *
2974 * Set the real number of both TX and RX queues.
2975 * Does nothing if the number of queues is already correct.
2976 */
2977int netif_set_real_num_queues(struct net_device *dev,
2978 unsigned int txq, unsigned int rxq)
2979{
2980 unsigned int old_rxq = dev->real_num_rx_queues;
2981 int err;
2982
2983 if (txq < 1 || txq > dev->num_tx_queues ||
2984 rxq < 1 || rxq > dev->num_rx_queues)
2985 return -EINVAL;
2986
2987 /* Start from increases, so the error path only does decreases -
2988 * decreases can't fail.
2989 */
2990 if (rxq > dev->real_num_rx_queues) {
2991 err = netif_set_real_num_rx_queues(dev, rxq);
2992 if (err)
2993 return err;
2994 }
2995 if (txq > dev->real_num_tx_queues) {
2996 err = netif_set_real_num_tx_queues(dev, txq);
2997 if (err)
2998 goto undo_rx;
2999 }
3000 if (rxq < dev->real_num_rx_queues)
3001 WARN_ON(netif_set_real_num_rx_queues(dev, rxq));
3002 if (txq < dev->real_num_tx_queues)
3003 WARN_ON(netif_set_real_num_tx_queues(dev, txq));
3004
3005 return 0;
3006undo_rx:
3007 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq));
3008 return err;
3009}
3010EXPORT_SYMBOL(netif_set_real_num_queues);
3011
3012/**
3013 * netif_set_tso_max_size() - set the max size of TSO frames supported
3014 * @dev: netdev to update
3015 * @size: max skb->len of a TSO frame
3016 *
3017 * Set the limit on the size of TSO super-frames the device can handle.
3018 * Unless explicitly set the stack will assume the value of
3019 * %GSO_LEGACY_MAX_SIZE.
3020 */
3021void netif_set_tso_max_size(struct net_device *dev, unsigned int size)
3022{
3023 dev->tso_max_size = min(GSO_MAX_SIZE, size);
3024 if (size < READ_ONCE(dev->gso_max_size))
3025 netif_set_gso_max_size(dev, size);
3026 if (size < READ_ONCE(dev->gso_ipv4_max_size))
3027 netif_set_gso_ipv4_max_size(dev, size);
3028}
3029EXPORT_SYMBOL(netif_set_tso_max_size);
3030
3031/**
3032 * netif_set_tso_max_segs() - set the max number of segs supported for TSO
3033 * @dev: netdev to update
3034 * @segs: max number of TCP segments
3035 *
3036 * Set the limit on the number of TCP segments the device can generate from
3037 * a single TSO super-frame.
3038 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS.
3039 */
3040void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs)
3041{
3042 dev->tso_max_segs = segs;
3043 if (segs < READ_ONCE(dev->gso_max_segs))
3044 netif_set_gso_max_segs(dev, segs);
3045}
3046EXPORT_SYMBOL(netif_set_tso_max_segs);
3047
3048/**
3049 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper
3050 * @to: netdev to update
3051 * @from: netdev from which to copy the limits
3052 */
3053void netif_inherit_tso_max(struct net_device *to, const struct net_device *from)
3054{
3055 netif_set_tso_max_size(to, from->tso_max_size);
3056 netif_set_tso_max_segs(to, from->tso_max_segs);
3057}
3058EXPORT_SYMBOL(netif_inherit_tso_max);
3059
3060/**
3061 * netif_get_num_default_rss_queues - default number of RSS queues
3062 *
3063 * Default value is the number of physical cores if there are only 1 or 2, or
3064 * divided by 2 if there are more.
3065 */
3066int netif_get_num_default_rss_queues(void)
3067{
3068 cpumask_var_t cpus;
3069 int cpu, count = 0;
3070
3071 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL)))
3072 return 1;
3073
3074 cpumask_copy(dstp: cpus, cpu_online_mask);
3075 for_each_cpu(cpu, cpus) {
3076 ++count;
3077 cpumask_andnot(dstp: cpus, src1p: cpus, topology_sibling_cpumask(cpu));
3078 }
3079 free_cpumask_var(mask: cpus);
3080
3081 return count > 2 ? DIV_ROUND_UP(count, 2) : count;
3082}
3083EXPORT_SYMBOL(netif_get_num_default_rss_queues);
3084
3085static void __netif_reschedule(struct Qdisc *q)
3086{
3087 struct softnet_data *sd;
3088 unsigned long flags;
3089
3090 local_irq_save(flags);
3091 sd = this_cpu_ptr(&softnet_data);
3092 q->next_sched = NULL;
3093 *sd->output_queue_tailp = q;
3094 sd->output_queue_tailp = &q->next_sched;
3095 raise_softirq_irqoff(nr: NET_TX_SOFTIRQ);
3096 local_irq_restore(flags);
3097}
3098
3099void __netif_schedule(struct Qdisc *q)
3100{
3101 if (!test_and_set_bit(nr: __QDISC_STATE_SCHED, addr: &q->state))
3102 __netif_reschedule(q);
3103}
3104EXPORT_SYMBOL(__netif_schedule);
3105
3106struct dev_kfree_skb_cb {
3107 enum skb_drop_reason reason;
3108};
3109
3110static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
3111{
3112 return (struct dev_kfree_skb_cb *)skb->cb;
3113}
3114
3115void netif_schedule_queue(struct netdev_queue *txq)
3116{
3117 rcu_read_lock();
3118 if (!netif_xmit_stopped(dev_queue: txq)) {
3119 struct Qdisc *q = rcu_dereference(txq->qdisc);
3120
3121 __netif_schedule(q);
3122 }
3123 rcu_read_unlock();
3124}
3125EXPORT_SYMBOL(netif_schedule_queue);
3126
3127void netif_tx_wake_queue(struct netdev_queue *dev_queue)
3128{
3129 if (test_and_clear_bit(nr: __QUEUE_STATE_DRV_XOFF, addr: &dev_queue->state)) {
3130 struct Qdisc *q;
3131
3132 rcu_read_lock();
3133 q = rcu_dereference(dev_queue->qdisc);
3134 __netif_schedule(q);
3135 rcu_read_unlock();
3136 }
3137}
3138EXPORT_SYMBOL(netif_tx_wake_queue);
3139
3140void dev_kfree_skb_irq_reason(struct sk_buff *skb, enum skb_drop_reason reason)
3141{
3142 unsigned long flags;
3143
3144 if (unlikely(!skb))
3145 return;
3146
3147 if (likely(refcount_read(&skb->users) == 1)) {
3148 smp_rmb();
3149 refcount_set(r: &skb->users, n: 0);
3150 } else if (likely(!refcount_dec_and_test(&skb->users))) {
3151 return;
3152 }
3153 get_kfree_skb_cb(skb)->reason = reason;
3154 local_irq_save(flags);
3155 skb->next = __this_cpu_read(softnet_data.completion_queue);
3156 __this_cpu_write(softnet_data.completion_queue, skb);
3157 raise_softirq_irqoff(nr: NET_TX_SOFTIRQ);
3158 local_irq_restore(flags);
3159}
3160EXPORT_SYMBOL(dev_kfree_skb_irq_reason);
3161
3162void dev_kfree_skb_any_reason(struct sk_buff *skb, enum skb_drop_reason reason)
3163{
3164 if (in_hardirq() || irqs_disabled())
3165 dev_kfree_skb_irq_reason(skb, reason);
3166 else
3167 kfree_skb_reason(skb, reason);
3168}
3169EXPORT_SYMBOL(dev_kfree_skb_any_reason);
3170
3171
3172/**
3173 * netif_device_detach - mark device as removed
3174 * @dev: network device
3175 *
3176 * Mark device as removed from system and therefore no longer available.
3177 */
3178void netif_device_detach(struct net_device *dev)
3179{
3180 if (test_and_clear_bit(nr: __LINK_STATE_PRESENT, addr: &dev->state) &&
3181 netif_running(dev)) {
3182 netif_tx_stop_all_queues(dev);
3183 }
3184}
3185EXPORT_SYMBOL(netif_device_detach);
3186
3187/**
3188 * netif_device_attach - mark device as attached
3189 * @dev: network device
3190 *
3191 * Mark device as attached from system and restart if needed.
3192 */
3193void netif_device_attach(struct net_device *dev)
3194{
3195 if (!test_and_set_bit(nr: __LINK_STATE_PRESENT, addr: &dev->state) &&
3196 netif_running(dev)) {
3197 netif_tx_wake_all_queues(dev);
3198 __netdev_watchdog_up(dev);
3199 }
3200}
3201EXPORT_SYMBOL(netif_device_attach);
3202
3203/*
3204 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
3205 * to be used as a distribution range.
3206 */
3207static u16 skb_tx_hash(const struct net_device *dev,
3208 const struct net_device *sb_dev,
3209 struct sk_buff *skb)
3210{
3211 u32 hash;
3212 u16 qoffset = 0;
3213 u16 qcount = dev->real_num_tx_queues;
3214
3215 if (dev->num_tc) {
3216 u8 tc = netdev_get_prio_tc_map(dev, prio: skb->priority);
3217
3218 qoffset = sb_dev->tc_to_txq[tc].offset;
3219 qcount = sb_dev->tc_to_txq[tc].count;
3220 if (unlikely(!qcount)) {
3221 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n",
3222 sb_dev->name, qoffset, tc);
3223 qoffset = 0;
3224 qcount = dev->real_num_tx_queues;
3225 }
3226 }
3227
3228 if (skb_rx_queue_recorded(skb)) {
3229 DEBUG_NET_WARN_ON_ONCE(qcount == 0);
3230 hash = skb_get_rx_queue(skb);
3231 if (hash >= qoffset)
3232 hash -= qoffset;
3233 while (unlikely(hash >= qcount))
3234 hash -= qcount;
3235 return hash + qoffset;
3236 }
3237
3238 return (u16) reciprocal_scale(val: skb_get_hash(skb), ep_ro: qcount) + qoffset;
3239}
3240
3241void skb_warn_bad_offload(const struct sk_buff *skb)
3242{
3243 static const netdev_features_t null_features;
3244 struct net_device *dev = skb->dev;
3245 const char *name = "";
3246
3247 if (!net_ratelimit())
3248 return;
3249
3250 if (dev) {
3251 if (dev->dev.parent)
3252 name = dev_driver_string(dev: dev->dev.parent);
3253 else
3254 name = netdev_name(dev);
3255 }
3256 skb_dump(KERN_WARNING, skb, full_pkt: false);
3257 WARN(1, "%s: caps=(%pNF, %pNF)\n",
3258 name, dev ? &dev->features : &null_features,
3259 skb->sk ? &skb->sk->sk_route_caps : &null_features);
3260}
3261
3262/*
3263 * Invalidate hardware checksum when packet is to be mangled, and
3264 * complete checksum manually on outgoing path.
3265 */
3266int skb_checksum_help(struct sk_buff *skb)
3267{
3268 __wsum csum;
3269 int ret = 0, offset;
3270
3271 if (skb->ip_summed == CHECKSUM_COMPLETE)
3272 goto out_set_summed;
3273
3274 if (unlikely(skb_is_gso(skb))) {
3275 skb_warn_bad_offload(skb);
3276 return -EINVAL;
3277 }
3278
3279 /* Before computing a checksum, we should make sure no frag could
3280 * be modified by an external entity : checksum could be wrong.
3281 */
3282 if (skb_has_shared_frag(skb)) {
3283 ret = __skb_linearize(skb);
3284 if (ret)
3285 goto out;
3286 }
3287
3288 offset = skb_checksum_start_offset(skb);
3289 ret = -EINVAL;
3290 if (unlikely(offset >= skb_headlen(skb))) {
3291 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false);
3292 WARN_ONCE(true, "offset (%d) >= skb_headlen() (%u)\n",
3293 offset, skb_headlen(skb));
3294 goto out;
3295 }
3296 csum = skb_checksum(skb, offset, len: skb->len - offset, csum: 0);
3297
3298 offset += skb->csum_offset;
3299 if (unlikely(offset + sizeof(__sum16) > skb_headlen(skb))) {
3300 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false);
3301 WARN_ONCE(true, "offset+2 (%zu) > skb_headlen() (%u)\n",
3302 offset + sizeof(__sum16), skb_headlen(skb));
3303 goto out;
3304 }
3305 ret = skb_ensure_writable(skb, write_len: offset + sizeof(__sum16));
3306 if (ret)
3307 goto out;
3308
3309 *(__sum16 *)(skb->data + offset) = csum_fold(sum: csum) ?: CSUM_MANGLED_0;
3310out_set_summed:
3311 skb->ip_summed = CHECKSUM_NONE;
3312out:
3313 return ret;
3314}
3315EXPORT_SYMBOL(skb_checksum_help);
3316
3317int skb_crc32c_csum_help(struct sk_buff *skb)
3318{
3319 __le32 crc32c_csum;
3320 int ret = 0, offset, start;
3321
3322 if (skb->ip_summed != CHECKSUM_PARTIAL)
3323 goto out;
3324
3325 if (unlikely(skb_is_gso(skb)))
3326 goto out;
3327
3328 /* Before computing a checksum, we should make sure no frag could
3329 * be modified by an external entity : checksum could be wrong.
3330 */
3331 if (unlikely(skb_has_shared_frag(skb))) {
3332 ret = __skb_linearize(skb);
3333 if (ret)
3334 goto out;
3335 }
3336 start = skb_checksum_start_offset(skb);
3337 offset = start + offsetof(struct sctphdr, checksum);
3338 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) {
3339 ret = -EINVAL;
3340 goto out;
3341 }
3342
3343 ret = skb_ensure_writable(skb, write_len: offset + sizeof(__le32));
3344 if (ret)
3345 goto out;
3346
3347 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start,
3348 skb->len - start, ~(__u32)0,
3349 crc32c_csum_stub));
3350 *(__le32 *)(skb->data + offset) = crc32c_csum;
3351 skb_reset_csum_not_inet(skb);
3352out:
3353 return ret;
3354}
3355
3356__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
3357{
3358 __be16 type = skb->protocol;
3359
3360 /* Tunnel gso handlers can set protocol to ethernet. */
3361 if (type == htons(ETH_P_TEB)) {
3362 struct ethhdr *eth;
3363
3364 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
3365 return 0;
3366
3367 eth = (struct ethhdr *)skb->data;
3368 type = eth->h_proto;
3369 }
3370
3371 return vlan_get_protocol_and_depth(skb, type, depth);
3372}
3373
3374
3375/* Take action when hardware reception checksum errors are detected. */
3376#ifdef CONFIG_BUG
3377static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
3378{
3379 netdev_err(dev, format: "hw csum failure\n");
3380 skb_dump(KERN_ERR, skb, full_pkt: true);
3381 dump_stack();
3382}
3383
3384void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
3385{
3386 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb);
3387}
3388EXPORT_SYMBOL(netdev_rx_csum_fault);
3389#endif
3390
3391/* XXX: check that highmem exists at all on the given machine. */
3392static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
3393{
3394#ifdef CONFIG_HIGHMEM
3395 int i;
3396
3397 if (!(dev->features & NETIF_F_HIGHDMA)) {
3398 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
3399 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
3400
3401 if (PageHighMem(skb_frag_page(frag)))
3402 return 1;
3403 }
3404 }
3405#endif
3406 return 0;
3407}
3408
3409/* If MPLS offload request, verify we are testing hardware MPLS features
3410 * instead of standard features for the netdev.
3411 */
3412#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
3413static netdev_features_t net_mpls_features(struct sk_buff *skb,
3414 netdev_features_t features,
3415 __be16 type)
3416{
3417 if (eth_p_mpls(eth_type: type))
3418 features &= skb->dev->mpls_features;
3419
3420 return features;
3421}
3422#else
3423static netdev_features_t net_mpls_features(struct sk_buff *skb,
3424 netdev_features_t features,
3425 __be16 type)
3426{
3427 return features;
3428}
3429#endif
3430
3431static netdev_features_t harmonize_features(struct sk_buff *skb,
3432 netdev_features_t features)
3433{
3434 __be16 type;
3435
3436 type = skb_network_protocol(skb, NULL);
3437 features = net_mpls_features(skb, features, type);
3438
3439 if (skb->ip_summed != CHECKSUM_NONE &&
3440 !can_checksum_protocol(features, protocol: type)) {
3441 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
3442 }
3443 if (illegal_highdma(dev: skb->dev, skb))
3444 features &= ~NETIF_F_SG;
3445
3446 return features;
3447}
3448
3449netdev_features_t passthru_features_check(struct sk_buff *skb,
3450 struct net_device *dev,
3451 netdev_features_t features)
3452{
3453 return features;
3454}
3455EXPORT_SYMBOL(passthru_features_check);
3456
3457static netdev_features_t dflt_features_check(struct sk_buff *skb,
3458 struct net_device *dev,
3459 netdev_features_t features)
3460{
3461 return vlan_features_check(skb, features);
3462}
3463
3464static netdev_features_t gso_features_check(const struct sk_buff *skb,
3465 struct net_device *dev,
3466 netdev_features_t features)
3467{
3468 u16 gso_segs = skb_shinfo(skb)->gso_segs;
3469
3470 if (gso_segs > READ_ONCE(dev->gso_max_segs))
3471 return features & ~NETIF_F_GSO_MASK;
3472
3473 if (!skb_shinfo(skb)->gso_type) {
3474 skb_warn_bad_offload(skb);
3475 return features & ~NETIF_F_GSO_MASK;
3476 }
3477
3478 /* Support for GSO partial features requires software
3479 * intervention before we can actually process the packets
3480 * so we need to strip support for any partial features now
3481 * and we can pull them back in after we have partially
3482 * segmented the frame.
3483 */
3484 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL))
3485 features &= ~dev->gso_partial_features;
3486
3487 /* Make sure to clear the IPv4 ID mangling feature if the
3488 * IPv4 header has the potential to be fragmented.
3489 */
3490 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
3491 struct iphdr *iph = skb->encapsulation ?
3492 inner_ip_hdr(skb) : ip_hdr(skb);
3493
3494 if (!(iph->frag_off & htons(IP_DF)))
3495 features &= ~NETIF_F_TSO_MANGLEID;
3496 }
3497
3498 return features;
3499}
3500
3501netdev_features_t netif_skb_features(struct sk_buff *skb)
3502{
3503 struct net_device *dev = skb->dev;
3504 netdev_features_t features = dev->features;
3505
3506 if (skb_is_gso(skb))
3507 features = gso_features_check(skb, dev, features);
3508
3509 /* If encapsulation offload request, verify we are testing
3510 * hardware encapsulation features instead of standard
3511 * features for the netdev
3512 */
3513 if (skb->encapsulation)
3514 features &= dev->hw_enc_features;
3515
3516 if (skb_vlan_tagged(skb))
3517 features = netdev_intersect_features(f1: features,
3518 f2: dev->vlan_features |
3519 NETIF_F_HW_VLAN_CTAG_TX |
3520 NETIF_F_HW_VLAN_STAG_TX);
3521
3522 if (dev->netdev_ops->ndo_features_check)
3523 features &= dev->netdev_ops->ndo_features_check(skb, dev,
3524 features);
3525 else
3526 features &= dflt_features_check(skb, dev, features);
3527
3528 return harmonize_features(skb, features);
3529}
3530EXPORT_SYMBOL(netif_skb_features);
3531
3532static int xmit_one(struct sk_buff *skb, struct net_device *dev,
3533 struct netdev_queue *txq, bool more)
3534{
3535 unsigned int len;
3536 int rc;
3537
3538 if (dev_nit_active(dev))
3539 dev_queue_xmit_nit(skb, dev);
3540
3541 len = skb->len;
3542 trace_net_dev_start_xmit(skb, dev);
3543 rc = netdev_start_xmit(skb, dev, txq, more);
3544 trace_net_dev_xmit(skb, rc, dev, skb_len: len);
3545
3546 return rc;
3547}
3548
3549struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
3550 struct netdev_queue *txq, int *ret)
3551{
3552 struct sk_buff *skb = first;
3553 int rc = NETDEV_TX_OK;
3554
3555 while (skb) {
3556 struct sk_buff *next = skb->next;
3557
3558 skb_mark_not_on_list(skb);
3559 rc = xmit_one(skb, dev, txq, more: next != NULL);
3560 if (unlikely(!dev_xmit_complete(rc))) {
3561 skb->next = next;
3562 goto out;
3563 }
3564
3565 skb = next;
3566 if (netif_tx_queue_stopped(dev_queue: txq) && skb) {
3567 rc = NETDEV_TX_BUSY;
3568 break;
3569 }
3570 }
3571
3572out:
3573 *ret = rc;
3574 return skb;
3575}
3576
3577static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
3578 netdev_features_t features)
3579{
3580 if (skb_vlan_tag_present(skb) &&
3581 !vlan_hw_offload_capable(features, proto: skb->vlan_proto))
3582 skb = __vlan_hwaccel_push_inside(skb);
3583 return skb;
3584}
3585
3586int skb_csum_hwoffload_help(struct sk_buff *skb,
3587 const netdev_features_t features)
3588{
3589 if (unlikely(skb_csum_is_sctp(skb)))
3590 return !!(features & NETIF_F_SCTP_CRC) ? 0 :
3591 skb_crc32c_csum_help(skb);
3592
3593 if (features & NETIF_F_HW_CSUM)
3594 return 0;
3595
3596 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) {
3597 switch (skb->csum_offset) {
3598 case offsetof(struct tcphdr, check):
3599 case offsetof(struct udphdr, check):
3600 return 0;
3601 }
3602 }
3603
3604 return skb_checksum_help(skb);
3605}
3606EXPORT_SYMBOL(skb_csum_hwoffload_help);
3607
3608static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again)
3609{
3610 netdev_features_t features;
3611
3612 features = netif_skb_features(skb);
3613 skb = validate_xmit_vlan(skb, features);
3614 if (unlikely(!skb))
3615 goto out_null;
3616
3617 skb = sk_validate_xmit_skb(skb, dev);
3618 if (unlikely(!skb))
3619 goto out_null;
3620
3621 if (netif_needs_gso(skb, features)) {
3622 struct sk_buff *segs;
3623
3624 segs = skb_gso_segment(skb, features);
3625 if (IS_ERR(ptr: segs)) {
3626 goto out_kfree_skb;
3627 } else if (segs) {
3628 consume_skb(skb);
3629 skb = segs;
3630 }
3631 } else {
3632 if (skb_needs_linearize(skb, features) &&
3633 __skb_linearize(skb))
3634 goto out_kfree_skb;
3635
3636 /* If packet is not checksummed and device does not
3637 * support checksumming for this protocol, complete
3638 * checksumming here.
3639 */
3640 if (skb->ip_summed == CHECKSUM_PARTIAL) {
3641 if (skb->encapsulation)
3642 skb_set_inner_transport_header(skb,
3643 offset: skb_checksum_start_offset(skb));
3644 else
3645 skb_set_transport_header(skb,
3646 offset: skb_checksum_start_offset(skb));
3647 if (skb_csum_hwoffload_help(skb, features))
3648 goto out_kfree_skb;
3649 }
3650 }
3651
3652 skb = validate_xmit_xfrm(skb, features, again);
3653
3654 return skb;
3655
3656out_kfree_skb:
3657 kfree_skb(skb);
3658out_null:
3659 dev_core_stats_tx_dropped_inc(dev);
3660 return NULL;
3661}
3662
3663struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again)
3664{
3665 struct sk_buff *next, *head = NULL, *tail;
3666
3667 for (; skb != NULL; skb = next) {
3668 next = skb->next;
3669 skb_mark_not_on_list(skb);
3670
3671 /* in case skb wont be segmented, point to itself */
3672 skb->prev = skb;
3673
3674 skb = validate_xmit_skb(skb, dev, again);
3675 if (!skb)
3676 continue;
3677
3678 if (!head)
3679 head = skb;
3680 else
3681 tail->next = skb;
3682 /* If skb was segmented, skb->prev points to
3683 * the last segment. If not, it still contains skb.
3684 */
3685 tail = skb->prev;
3686 }
3687 return head;
3688}
3689EXPORT_SYMBOL_GPL(validate_xmit_skb_list);
3690
3691static void qdisc_pkt_len_init(struct sk_buff *skb)
3692{
3693 const struct skb_shared_info *shinfo = skb_shinfo(skb);
3694
3695 qdisc_skb_cb(skb)->pkt_len = skb->len;
3696
3697 /* To get more precise estimation of bytes sent on wire,
3698 * we add to pkt_len the headers size of all segments
3699 */
3700 if (shinfo->gso_size && skb_transport_header_was_set(skb)) {
3701 u16 gso_segs = shinfo->gso_segs;
3702 unsigned int hdr_len;
3703
3704 /* mac layer + network layer */
3705 hdr_len = skb_transport_offset(skb);
3706
3707 /* + transport layer */
3708 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
3709 const struct tcphdr *th;
3710 struct tcphdr _tcphdr;
3711
3712 th = skb_header_pointer(skb, offset: hdr_len,
3713 len: sizeof(_tcphdr), buffer: &_tcphdr);
3714 if (likely(th))
3715 hdr_len += __tcp_hdrlen(th);
3716 } else {
3717 struct udphdr _udphdr;
3718
3719 if (skb_header_pointer(skb, offset: hdr_len,
3720 len: sizeof(_udphdr), buffer: &_udphdr))
3721 hdr_len += sizeof(struct udphdr);
3722 }
3723
3724 if (shinfo->gso_type & SKB_GSO_DODGY)
3725 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
3726 shinfo->gso_size);
3727
3728 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
3729 }
3730}
3731
3732static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q,
3733 struct sk_buff **to_free,
3734 struct netdev_queue *txq)
3735{
3736 int rc;
3737
3738 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK;
3739 if (rc == NET_XMIT_SUCCESS)
3740 trace_qdisc_enqueue(qdisc: q, txq, skb);
3741 return rc;
3742}
3743
3744static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
3745 struct net_device *dev,
3746 struct netdev_queue *txq)
3747{
3748 spinlock_t *root_lock = qdisc_lock(qdisc: q);
3749 struct sk_buff *to_free = NULL;
3750 bool contended;
3751 int rc;
3752
3753 qdisc_calculate_pkt_len(skb, sch: q);
3754
3755 if (q->flags & TCQ_F_NOLOCK) {
3756 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(qdisc: q) &&
3757 qdisc_run_begin(qdisc: q)) {
3758 /* Retest nolock_qdisc_is_empty() within the protection
3759 * of q->seqlock to protect from racing with requeuing.
3760 */
3761 if (unlikely(!nolock_qdisc_is_empty(q))) {
3762 rc = dev_qdisc_enqueue(skb, q, to_free: &to_free, txq);
3763 __qdisc_run(q);
3764 qdisc_run_end(qdisc: q);
3765
3766 goto no_lock_out;
3767 }
3768
3769 qdisc_bstats_cpu_update(sch: q, skb);
3770 if (sch_direct_xmit(skb, q, dev, txq, NULL, validate: true) &&
3771 !nolock_qdisc_is_empty(qdisc: q))
3772 __qdisc_run(q);
3773
3774 qdisc_run_end(qdisc: q);
3775 return NET_XMIT_SUCCESS;
3776 }
3777
3778 rc = dev_qdisc_enqueue(skb, q, to_free: &to_free, txq);
3779 qdisc_run(q);
3780
3781no_lock_out:
3782 if (unlikely(to_free))
3783 kfree_skb_list_reason(segs: to_free,
3784 reason: SKB_DROP_REASON_QDISC_DROP);
3785 return rc;
3786 }
3787
3788 /*
3789 * Heuristic to force contended enqueues to serialize on a
3790 * separate lock before trying to get qdisc main lock.
3791 * This permits qdisc->running owner to get the lock more
3792 * often and dequeue packets faster.
3793 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit
3794 * and then other tasks will only enqueue packets. The packets will be
3795 * sent after the qdisc owner is scheduled again. To prevent this
3796 * scenario the task always serialize on the lock.
3797 */
3798 contended = qdisc_is_running(qdisc: q) || IS_ENABLED(CONFIG_PREEMPT_RT);
3799 if (unlikely(contended))
3800 spin_lock(lock: &q->busylock);
3801
3802 spin_lock(lock: root_lock);
3803 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
3804 __qdisc_drop(skb, to_free: &to_free);
3805 rc = NET_XMIT_DROP;
3806 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
3807 qdisc_run_begin(qdisc: q)) {
3808 /*
3809 * This is a work-conserving queue; there are no old skbs
3810 * waiting to be sent out; and the qdisc is not running -
3811 * xmit the skb directly.
3812 */
3813
3814 qdisc_bstats_update(sch: q, skb);
3815
3816 if (sch_direct_xmit(skb, q, dev, txq, root_lock, validate: true)) {
3817 if (unlikely(contended)) {
3818 spin_unlock(lock: &q->busylock);
3819 contended = false;
3820 }
3821 __qdisc_run(q);
3822 }
3823
3824 qdisc_run_end(qdisc: q);
3825 rc = NET_XMIT_SUCCESS;
3826 } else {
3827 rc = dev_qdisc_enqueue(skb, q, to_free: &to_free, txq);
3828 if (qdisc_run_begin(qdisc: q)) {
3829 if (unlikely(contended)) {
3830 spin_unlock(lock: &q->busylock);
3831 contended = false;
3832 }
3833 __qdisc_run(q);
3834 qdisc_run_end(qdisc: q);
3835 }
3836 }
3837 spin_unlock(lock: root_lock);
3838 if (unlikely(to_free))
3839 kfree_skb_list_reason(segs: to_free, reason: SKB_DROP_REASON_QDISC_DROP);
3840 if (unlikely(contended))
3841 spin_unlock(lock: &q->busylock);
3842 return rc;
3843}
3844
3845#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
3846static void skb_update_prio(struct sk_buff *skb)
3847{
3848 const struct netprio_map *map;
3849 const struct sock *sk;
3850 unsigned int prioidx;
3851
3852 if (skb->priority)
3853 return;
3854 map = rcu_dereference_bh(skb->dev->priomap);
3855 if (!map)
3856 return;
3857 sk = skb_to_full_sk(skb);
3858 if (!sk)
3859 return;
3860
3861 prioidx = sock_cgroup_prioidx(skcd: &sk->sk_cgrp_data);
3862
3863 if (prioidx < map->priomap_len)
3864 skb->priority = map->priomap[prioidx];
3865}
3866#else
3867#define skb_update_prio(skb)
3868#endif
3869
3870/**
3871 * dev_loopback_xmit - loop back @skb
3872 * @net: network namespace this loopback is happening in
3873 * @sk: sk needed to be a netfilter okfn
3874 * @skb: buffer to transmit
3875 */
3876int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
3877{
3878 skb_reset_mac_header(skb);
3879 __skb_pull(skb, len: skb_network_offset(skb));
3880 skb->pkt_type = PACKET_LOOPBACK;
3881 if (skb->ip_summed == CHECKSUM_NONE)
3882 skb->ip_summed = CHECKSUM_UNNECESSARY;
3883 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb));
3884 skb_dst_force(skb);
3885 netif_rx(skb);
3886 return 0;
3887}
3888EXPORT_SYMBOL(dev_loopback_xmit);
3889
3890#ifdef CONFIG_NET_EGRESS
3891static struct netdev_queue *
3892netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb)
3893{
3894 int qm = skb_get_queue_mapping(skb);
3895
3896 return netdev_get_tx_queue(dev, index: netdev_cap_txqueue(dev, queue_index: qm));
3897}
3898
3899static bool netdev_xmit_txqueue_skipped(void)
3900{
3901 return __this_cpu_read(softnet_data.xmit.skip_txqueue);
3902}
3903
3904void netdev_xmit_skip_txqueue(bool skip)
3905{
3906 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip);
3907}
3908EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue);
3909#endif /* CONFIG_NET_EGRESS */
3910
3911#ifdef CONFIG_NET_XGRESS
3912static int tc_run(struct tcx_entry *entry, struct sk_buff *skb,
3913 enum skb_drop_reason *drop_reason)
3914{
3915 int ret = TC_ACT_UNSPEC;
3916#ifdef CONFIG_NET_CLS_ACT
3917 struct mini_Qdisc *miniq = rcu_dereference_bh(entry->miniq);
3918 struct tcf_result res;
3919
3920 if (!miniq)
3921 return ret;
3922
3923 tc_skb_cb(skb)->mru = 0;
3924 tc_skb_cb(skb)->post_ct = false;
3925 res.drop_reason = *drop_reason;
3926
3927 mini_qdisc_bstats_cpu_update(miniq, skb);
3928 ret = tcf_classify(skb, block: miniq->block, tp: miniq->filter_list, res: &res, compat_mode: false);
3929 /* Only tcf related quirks below. */
3930 switch (ret) {
3931 case TC_ACT_SHOT:
3932 *drop_reason = res.drop_reason;
3933 mini_qdisc_qstats_cpu_drop(miniq);
3934 break;
3935 case TC_ACT_OK:
3936 case TC_ACT_RECLASSIFY:
3937 skb->tc_index = TC_H_MIN(res.classid);
3938 break;
3939 }
3940#endif /* CONFIG_NET_CLS_ACT */
3941 return ret;
3942}
3943
3944static DEFINE_STATIC_KEY_FALSE(tcx_needed_key);
3945
3946void tcx_inc(void)
3947{
3948 static_branch_inc(&tcx_needed_key);
3949}
3950
3951void tcx_dec(void)
3952{
3953 static_branch_dec(&tcx_needed_key);
3954}
3955
3956static __always_inline enum tcx_action_base
3957tcx_run(const struct bpf_mprog_entry *entry, struct sk_buff *skb,
3958 const bool needs_mac)
3959{
3960 const struct bpf_mprog_fp *fp;
3961 const struct bpf_prog *prog;
3962 int ret = TCX_NEXT;
3963
3964 if (needs_mac)
3965 __skb_push(skb, len: skb->mac_len);
3966 bpf_mprog_foreach_prog(entry, fp, prog) {
3967 bpf_compute_data_pointers(skb);
3968 ret = bpf_prog_run(prog, ctx: skb);
3969 if (ret != TCX_NEXT)
3970 break;
3971 }
3972 if (needs_mac)
3973 __skb_pull(skb, len: skb->mac_len);
3974 return tcx_action_code(skb, code: ret);
3975}
3976
3977static __always_inline struct sk_buff *
3978sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
3979 struct net_device *orig_dev, bool *another)
3980{
3981 struct bpf_mprog_entry *entry = rcu_dereference_bh(skb->dev->tcx_ingress);
3982 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_INGRESS;
3983 int sch_ret;
3984
3985 if (!entry)
3986 return skb;
3987 if (*pt_prev) {
3988 *ret = deliver_skb(skb, pt_prev: *pt_prev, orig_dev);
3989 *pt_prev = NULL;
3990 }
3991
3992 qdisc_skb_cb(skb)->pkt_len = skb->len;
3993 tcx_set_ingress(skb, ingress: true);
3994
3995 if (static_branch_unlikely(&tcx_needed_key)) {
3996 sch_ret = tcx_run(entry, skb, needs_mac: true);
3997 if (sch_ret != TC_ACT_UNSPEC)
3998 goto ingress_verdict;
3999 }
4000 sch_ret = tc_run(entry: tcx_entry(entry), skb, drop_reason: &drop_reason);
4001ingress_verdict:
4002 switch (sch_ret) {
4003 case TC_ACT_REDIRECT:
4004 /* skb_mac_header check was done by BPF, so we can safely
4005 * push the L2 header back before redirecting to another
4006 * netdev.
4007 */
4008 __skb_push(skb, len: skb->mac_len);
4009 if (skb_do_redirect(skb) == -EAGAIN) {
4010 __skb_pull(skb, len: skb->mac_len);
4011 *another = true;
4012 break;
4013 }
4014 *ret = NET_RX_SUCCESS;
4015 return NULL;
4016 case TC_ACT_SHOT:
4017 kfree_skb_reason(skb, reason: drop_reason);
4018 *ret = NET_RX_DROP;
4019 return NULL;
4020 /* used by tc_run */
4021 case TC_ACT_STOLEN:
4022 case TC_ACT_QUEUED:
4023 case TC_ACT_TRAP:
4024 consume_skb(skb);
4025 fallthrough;
4026 case TC_ACT_CONSUMED:
4027 *ret = NET_RX_SUCCESS;
4028 return NULL;
4029 }
4030
4031 return skb;
4032}
4033
4034static __always_inline struct sk_buff *
4035sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
4036{
4037 struct bpf_mprog_entry *entry = rcu_dereference_bh(dev->tcx_egress);
4038 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_EGRESS;
4039 int sch_ret;
4040
4041 if (!entry)
4042 return skb;
4043
4044 /* qdisc_skb_cb(skb)->pkt_len & tcx_set_ingress() was
4045 * already set by the caller.
4046 */
4047 if (static_branch_unlikely(&tcx_needed_key)) {
4048 sch_ret = tcx_run(entry, skb, needs_mac: false);
4049 if (sch_ret != TC_ACT_UNSPEC)
4050 goto egress_verdict;
4051 }
4052 sch_ret = tc_run(entry: tcx_entry(entry), skb, drop_reason: &drop_reason);
4053egress_verdict:
4054 switch (sch_ret) {
4055 case TC_ACT_REDIRECT:
4056 /* No need to push/pop skb's mac_header here on egress! */
4057 skb_do_redirect(skb);
4058 *ret = NET_XMIT_SUCCESS;
4059 return NULL;
4060 case TC_ACT_SHOT:
4061 kfree_skb_reason(skb, reason: drop_reason);
4062 *ret = NET_XMIT_DROP;
4063 return NULL;
4064 /* used by tc_run */
4065 case TC_ACT_STOLEN:
4066 case TC_ACT_QUEUED:
4067 case TC_ACT_TRAP:
4068 consume_skb(skb);
4069 fallthrough;
4070 case TC_ACT_CONSUMED:
4071 *ret = NET_XMIT_SUCCESS;
4072 return NULL;
4073 }
4074
4075 return skb;
4076}
4077#else
4078static __always_inline struct sk_buff *
4079sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
4080 struct net_device *orig_dev, bool *another)
4081{
4082 return skb;
4083}
4084
4085static __always_inline struct sk_buff *
4086sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
4087{
4088 return skb;
4089}
4090#endif /* CONFIG_NET_XGRESS */
4091
4092#ifdef CONFIG_XPS
4093static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb,
4094 struct xps_dev_maps *dev_maps, unsigned int tci)
4095{
4096 int tc = netdev_get_prio_tc_map(dev, prio: skb->priority);
4097 struct xps_map *map;
4098 int queue_index = -1;
4099
4100 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids)
4101 return queue_index;
4102
4103 tci *= dev_maps->num_tc;
4104 tci += tc;
4105
4106 map = rcu_dereference(dev_maps->attr_map[tci]);
4107 if (map) {
4108 if (map->len == 1)
4109 queue_index = map->queues[0];
4110 else
4111 queue_index = map->queues[reciprocal_scale(
4112 val: skb_get_hash(skb), ep_ro: map->len)];
4113 if (unlikely(queue_index >= dev->real_num_tx_queues))
4114 queue_index = -1;
4115 }
4116 return queue_index;
4117}
4118#endif
4119
4120static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev,
4121 struct sk_buff *skb)
4122{
4123#ifdef CONFIG_XPS
4124 struct xps_dev_maps *dev_maps;
4125 struct sock *sk = skb->sk;
4126 int queue_index = -1;
4127
4128 if (!static_key_false(key: &xps_needed))
4129 return -1;
4130
4131 rcu_read_lock();
4132 if (!static_key_false(key: &xps_rxqs_needed))
4133 goto get_cpus_map;
4134
4135 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]);
4136 if (dev_maps) {
4137 int tci = sk_rx_queue_get(sk);
4138
4139 if (tci >= 0)
4140 queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
4141 tci);
4142 }
4143
4144get_cpus_map:
4145 if (queue_index < 0) {
4146 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]);
4147 if (dev_maps) {
4148 unsigned int tci = skb->sender_cpu - 1;
4149
4150 queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
4151 tci);
4152 }
4153 }
4154 rcu_read_unlock();
4155
4156 return queue_index;
4157#else
4158 return -1;
4159#endif
4160}
4161
4162u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb,
4163 struct net_device *sb_dev)
4164{
4165 return 0;
4166}
4167EXPORT_SYMBOL(dev_pick_tx_zero);
4168
4169u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb,
4170 struct net_device *sb_dev)
4171{
4172 return (u16)raw_smp_processor_id() % dev->real_num_tx_queues;
4173}
4174EXPORT_SYMBOL(dev_pick_tx_cpu_id);
4175
4176u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb,
4177 struct net_device *sb_dev)
4178{
4179 struct sock *sk = skb->sk;
4180 int queue_index = sk_tx_queue_get(sk);
4181
4182 sb_dev = sb_dev ? : dev;
4183
4184 if (queue_index < 0 || skb->ooo_okay ||
4185 queue_index >= dev->real_num_tx_queues) {
4186 int new_index = get_xps_queue(dev, sb_dev, skb);
4187
4188 if (new_index < 0)
4189 new_index = skb_tx_hash(dev, sb_dev, skb);
4190
4191 if (queue_index != new_index && sk &&
4192 sk_fullsock(sk) &&
4193 rcu_access_pointer(sk->sk_dst_cache))
4194 sk_tx_queue_set(sk, tx_queue: new_index);
4195
4196 queue_index = new_index;
4197 }
4198
4199 return queue_index;
4200}
4201EXPORT_SYMBOL(netdev_pick_tx);
4202
4203struct netdev_queue *netdev_core_pick_tx(struct net_device *dev,
4204 struct sk_buff *skb,
4205 struct net_device *sb_dev)
4206{
4207 int queue_index = 0;
4208
4209#ifdef CONFIG_XPS
4210 u32 sender_cpu = skb->sender_cpu - 1;
4211
4212 if (sender_cpu >= (u32)NR_CPUS)
4213 skb->sender_cpu = raw_smp_processor_id() + 1;
4214#endif
4215
4216 if (dev->real_num_tx_queues != 1) {
4217 const struct net_device_ops *ops = dev->netdev_ops;
4218
4219 if (ops->ndo_select_queue)
4220 queue_index = ops->ndo_select_queue(dev, skb, sb_dev);
4221 else
4222 queue_index = netdev_pick_tx(dev, skb, sb_dev);
4223
4224 queue_index = netdev_cap_txqueue(dev, queue_index);
4225 }
4226
4227 skb_set_queue_mapping(skb, queue_mapping: queue_index);
4228 return netdev_get_tx_queue(dev, index: queue_index);
4229}
4230
4231/**
4232 * __dev_queue_xmit() - transmit a buffer
4233 * @skb: buffer to transmit
4234 * @sb_dev: suboordinate device used for L2 forwarding offload
4235 *
4236 * Queue a buffer for transmission to a network device. The caller must
4237 * have set the device and priority and built the buffer before calling
4238 * this function. The function can be called from an interrupt.
4239 *
4240 * When calling this method, interrupts MUST be enabled. This is because
4241 * the BH enable code must have IRQs enabled so that it will not deadlock.
4242 *
4243 * Regardless of the return value, the skb is consumed, so it is currently
4244 * difficult to retry a send to this method. (You can bump the ref count
4245 * before sending to hold a reference for retry if you are careful.)
4246 *
4247 * Return:
4248 * * 0 - buffer successfully transmitted
4249 * * positive qdisc return code - NET_XMIT_DROP etc.
4250 * * negative errno - other errors
4251 */
4252int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev)
4253{
4254 struct net_device *dev = skb->dev;
4255 struct netdev_queue *txq = NULL;
4256 struct Qdisc *q;
4257 int rc = -ENOMEM;
4258 bool again = false;
4259
4260 skb_reset_mac_header(skb);
4261 skb_assert_len(skb);
4262
4263 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
4264 __skb_tstamp_tx(orig_skb: skb, NULL, NULL, sk: skb->sk, tstype: SCM_TSTAMP_SCHED);
4265
4266 /* Disable soft irqs for various locks below. Also
4267 * stops preemption for RCU.
4268 */
4269 rcu_read_lock_bh();
4270
4271 skb_update_prio(skb);
4272
4273 qdisc_pkt_len_init(skb);
4274 tcx_set_ingress(skb, ingress: false);
4275#ifdef CONFIG_NET_EGRESS
4276 if (static_branch_unlikely(&egress_needed_key)) {
4277 if (nf_hook_egress_active()) {
4278 skb = nf_hook_egress(skb, rc: &rc, dev);
4279 if (!skb)
4280 goto out;
4281 }
4282
4283 netdev_xmit_skip_txqueue(false);
4284
4285 nf_skip_egress(skb, skip: true);
4286 skb = sch_handle_egress(skb, ret: &rc, dev);
4287 if (!skb)
4288 goto out;
4289 nf_skip_egress(skb, skip: false);
4290
4291 if (netdev_xmit_txqueue_skipped())
4292 txq = netdev_tx_queue_mapping(dev, skb);
4293 }
4294#endif
4295 /* If device/qdisc don't need skb->dst, release it right now while
4296 * its hot in this cpu cache.
4297 */
4298 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
4299 skb_dst_drop(skb);
4300 else
4301 skb_dst_force(skb);
4302
4303 if (!txq)
4304 txq = netdev_core_pick_tx(dev, skb, sb_dev);
4305
4306 q = rcu_dereference_bh(txq->qdisc);
4307
4308 trace_net_dev_queue(skb);
4309 if (q->enqueue) {
4310 rc = __dev_xmit_skb(skb, q, dev, txq);
4311 goto out;
4312 }
4313
4314 /* The device has no queue. Common case for software devices:
4315 * loopback, all the sorts of tunnels...
4316
4317 * Really, it is unlikely that netif_tx_lock protection is necessary
4318 * here. (f.e. loopback and IP tunnels are clean ignoring statistics
4319 * counters.)
4320 * However, it is possible, that they rely on protection
4321 * made by us here.
4322
4323 * Check this and shot the lock. It is not prone from deadlocks.
4324 *Either shot noqueue qdisc, it is even simpler 8)
4325 */
4326 if (dev->flags & IFF_UP) {
4327 int cpu = smp_processor_id(); /* ok because BHs are off */
4328
4329 /* Other cpus might concurrently change txq->xmit_lock_owner
4330 * to -1 or to their cpu id, but not to our id.
4331 */
4332 if (READ_ONCE(txq->xmit_lock_owner) != cpu) {
4333 if (dev_xmit_recursion())
4334 goto recursion_alert;
4335
4336 skb = validate_xmit_skb(skb, dev, again: &again);
4337 if (!skb)
4338 goto out;
4339
4340 HARD_TX_LOCK(dev, txq, cpu);
4341
4342 if (!netif_xmit_stopped(dev_queue: txq)) {
4343 dev_xmit_recursion_inc();
4344 skb = dev_hard_start_xmit(first: skb, dev, txq, ret: &rc);
4345 dev_xmit_recursion_dec();
4346 if (dev_xmit_complete(rc)) {
4347 HARD_TX_UNLOCK(dev, txq);
4348 goto out;
4349 }
4350 }
4351 HARD_TX_UNLOCK(dev, txq);
4352 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
4353 dev->name);
4354 } else {
4355 /* Recursion is detected! It is possible,
4356 * unfortunately
4357 */
4358recursion_alert:
4359 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
4360 dev->name);
4361 }
4362 }
4363
4364 rc = -ENETDOWN;
4365 rcu_read_unlock_bh();
4366
4367 dev_core_stats_tx_dropped_inc(dev);
4368 kfree_skb_list(segs: skb);
4369 return rc;
4370out:
4371 rcu_read_unlock_bh();
4372 return rc;
4373}
4374EXPORT_SYMBOL(__dev_queue_xmit);
4375
4376int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id)
4377{
4378 struct net_device *dev = skb->dev;
4379 struct sk_buff *orig_skb = skb;
4380 struct netdev_queue *txq;
4381 int ret = NETDEV_TX_BUSY;
4382 bool again = false;
4383
4384 if (unlikely(!netif_running(dev) ||
4385 !netif_carrier_ok(dev)))
4386 goto drop;
4387
4388 skb = validate_xmit_skb_list(skb, dev, &again);
4389 if (skb != orig_skb)
4390 goto drop;
4391
4392 skb_set_queue_mapping(skb, queue_mapping: queue_id);
4393 txq = skb_get_tx_queue(dev, skb);
4394
4395 local_bh_disable();
4396
4397 dev_xmit_recursion_inc();
4398 HARD_TX_LOCK(dev, txq, smp_processor_id());
4399 if (!netif_xmit_frozen_or_drv_stopped(dev_queue: txq))
4400 ret = netdev_start_xmit(skb, dev, txq, more: false);
4401 HARD_TX_UNLOCK(dev, txq);
4402 dev_xmit_recursion_dec();
4403
4404 local_bh_enable();
4405 return ret;
4406drop:
4407 dev_core_stats_tx_dropped_inc(dev);
4408 kfree_skb_list(segs: skb);
4409 return NET_XMIT_DROP;
4410}
4411EXPORT_SYMBOL(__dev_direct_xmit);
4412
4413/*************************************************************************
4414 * Receiver routines
4415 *************************************************************************/
4416
4417int netdev_max_backlog __read_mostly = 1000;
4418EXPORT_SYMBOL(netdev_max_backlog);
4419
4420int netdev_tstamp_prequeue __read_mostly = 1;
4421unsigned int sysctl_skb_defer_max __read_mostly = 64;
4422int netdev_budget __read_mostly = 300;
4423/* Must be at least 2 jiffes to guarantee 1 jiffy timeout */
4424unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ;
4425int weight_p __read_mostly = 64; /* old backlog weight */
4426int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */
4427int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */
4428int dev_rx_weight __read_mostly = 64;
4429int dev_tx_weight __read_mostly = 64;
4430
4431/* Called with irq disabled */
4432static inline void ____napi_schedule(struct softnet_data *sd,
4433 struct napi_struct *napi)
4434{
4435 struct task_struct *thread;
4436
4437 lockdep_assert_irqs_disabled();
4438
4439 if (test_bit(NAPI_STATE_THREADED, &napi->state)) {
4440 /* Paired with smp_mb__before_atomic() in
4441 * napi_enable()/dev_set_threaded().
4442 * Use READ_ONCE() to guarantee a complete
4443 * read on napi->thread. Only call
4444 * wake_up_process() when it's not NULL.
4445 */
4446 thread = READ_ONCE(napi->thread);
4447 if (thread) {
4448 /* Avoid doing set_bit() if the thread is in
4449 * INTERRUPTIBLE state, cause napi_thread_wait()
4450 * makes sure to proceed with napi polling
4451 * if the thread is explicitly woken from here.
4452 */
4453 if (READ_ONCE(thread->__state) != TASK_INTERRUPTIBLE)
4454 set_bit(nr: NAPI_STATE_SCHED_THREADED, addr: &napi->state);
4455 wake_up_process(tsk: thread);
4456 return;
4457 }
4458 }
4459
4460 list_add_tail(new: &napi->poll_list, head: &sd->poll_list);
4461 WRITE_ONCE(napi->list_owner, smp_processor_id());
4462 /* If not called from net_rx_action()
4463 * we have to raise NET_RX_SOFTIRQ.
4464 */
4465 if (!sd->in_net_rx_action)
4466 __raise_softirq_irqoff(nr: NET_RX_SOFTIRQ);
4467}
4468
4469#ifdef CONFIG_RPS
4470
4471/* One global table that all flow-based protocols share. */
4472struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
4473EXPORT_SYMBOL(rps_sock_flow_table);
4474u32 rps_cpu_mask __read_mostly;
4475EXPORT_SYMBOL(rps_cpu_mask);
4476
4477struct static_key_false rps_needed __read_mostly;
4478EXPORT_SYMBOL(rps_needed);
4479struct static_key_false rfs_needed __read_mostly;
4480EXPORT_SYMBOL(rfs_needed);
4481
4482static struct rps_dev_flow *
4483set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
4484 struct rps_dev_flow *rflow, u16 next_cpu)
4485{
4486 if (next_cpu < nr_cpu_ids) {
4487#ifdef CONFIG_RFS_ACCEL
4488 struct netdev_rx_queue *rxqueue;
4489 struct rps_dev_flow_table *flow_table;
4490 struct rps_dev_flow *old_rflow;
4491 u32 flow_id;
4492 u16 rxq_index;
4493 int rc;
4494
4495 /* Should we steer this flow to a different hardware queue? */
4496 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
4497 !(dev->features & NETIF_F_NTUPLE))
4498 goto out;
4499 rxq_index = cpu_rmap_lookup_index(rmap: dev->rx_cpu_rmap, cpu: next_cpu);
4500 if (rxq_index == skb_get_rx_queue(skb))
4501 goto out;
4502
4503 rxqueue = dev->_rx + rxq_index;
4504 flow_table = rcu_dereference(rxqueue->rps_flow_table);
4505 if (!flow_table)
4506 goto out;
4507 flow_id = skb_get_hash(skb) & flow_table->mask;
4508 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
4509 rxq_index, flow_id);
4510 if (rc < 0)
4511 goto out;
4512 old_rflow = rflow;
4513 rflow = &flow_table->flows[flow_id];
4514 rflow->filter = rc;
4515 if (old_rflow->filter == rflow->filter)
4516 old_rflow->filter = RPS_NO_FILTER;
4517 out:
4518#endif
4519 rflow->last_qtail =
4520 per_cpu(softnet_data, next_cpu).input_queue_head;
4521 }
4522
4523 rflow->cpu = next_cpu;
4524 return rflow;
4525}
4526
4527/*
4528 * get_rps_cpu is called from netif_receive_skb and returns the target
4529 * CPU from the RPS map of the receiving queue for a given skb.
4530 * rcu_read_lock must be held on entry.
4531 */
4532static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
4533 struct rps_dev_flow **rflowp)
4534{
4535 const struct rps_sock_flow_table *sock_flow_table;
4536 struct netdev_rx_queue *rxqueue = dev->_rx;
4537 struct rps_dev_flow_table *flow_table;
4538 struct rps_map *map;
4539 int cpu = -1;
4540 u32 tcpu;
4541 u32 hash;
4542
4543 if (skb_rx_queue_recorded(skb)) {
4544 u16 index = skb_get_rx_queue(skb);
4545
4546 if (unlikely(index >= dev->real_num_rx_queues)) {
4547 WARN_ONCE(dev->real_num_rx_queues > 1,
4548 "%s received packet on queue %u, but number "
4549 "of RX queues is %u\n",
4550 dev->name, index, dev->real_num_rx_queues);
4551 goto done;
4552 }
4553 rxqueue += index;
4554 }
4555
4556 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */
4557
4558 flow_table = rcu_dereference(rxqueue->rps_flow_table);
4559 map = rcu_dereference(rxqueue->rps_map);
4560 if (!flow_table && !map)
4561 goto done;
4562
4563 skb_reset_network_header(skb);
4564 hash = skb_get_hash(skb);
4565 if (!hash)
4566 goto done;
4567
4568 sock_flow_table = rcu_dereference(rps_sock_flow_table);
4569 if (flow_table && sock_flow_table) {
4570 struct rps_dev_flow *rflow;
4571 u32 next_cpu;
4572 u32 ident;
4573
4574 /* First check into global flow table if there is a match.
4575 * This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow().
4576 */
4577 ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]);
4578 if ((ident ^ hash) & ~rps_cpu_mask)
4579 goto try_rps;
4580
4581 next_cpu = ident & rps_cpu_mask;
4582
4583 /* OK, now we know there is a match,
4584 * we can look at the local (per receive queue) flow table
4585 */
4586 rflow = &flow_table->flows[hash & flow_table->mask];
4587 tcpu = rflow->cpu;
4588
4589 /*
4590 * If the desired CPU (where last recvmsg was done) is
4591 * different from current CPU (one in the rx-queue flow
4592 * table entry), switch if one of the following holds:
4593 * - Current CPU is unset (>= nr_cpu_ids).
4594 * - Current CPU is offline.
4595 * - The current CPU's queue tail has advanced beyond the
4596 * last packet that was enqueued using this table entry.
4597 * This guarantees that all previous packets for the flow
4598 * have been dequeued, thus preserving in order delivery.
4599 */
4600 if (unlikely(tcpu != next_cpu) &&
4601 (tcpu >= nr_cpu_ids || !cpu_online(cpu: tcpu) ||
4602 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
4603 rflow->last_qtail)) >= 0)) {
4604 tcpu = next_cpu;
4605 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
4606 }
4607
4608 if (tcpu < nr_cpu_ids && cpu_online(cpu: tcpu)) {
4609 *rflowp = rflow;
4610 cpu = tcpu;
4611 goto done;
4612 }
4613 }
4614
4615try_rps:
4616
4617 if (map) {
4618 tcpu = map->cpus[reciprocal_scale(val: hash, ep_ro: map->len)];
4619 if (cpu_online(cpu: tcpu)) {
4620 cpu = tcpu;
4621 goto done;
4622 }
4623 }
4624
4625done:
4626 return cpu;
4627}
4628
4629#ifdef CONFIG_RFS_ACCEL
4630
4631/**
4632 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
4633 * @dev: Device on which the filter was set
4634 * @rxq_index: RX queue index
4635 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
4636 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
4637 *
4638 * Drivers that implement ndo_rx_flow_steer() should periodically call
4639 * this function for each installed filter and remove the filters for
4640 * which it returns %true.
4641 */
4642bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
4643 u32 flow_id, u16 filter_id)
4644{
4645 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
4646 struct rps_dev_flow_table *flow_table;
4647 struct rps_dev_flow *rflow;
4648 bool expire = true;
4649 unsigned int cpu;
4650
4651 rcu_read_lock();
4652 flow_table = rcu_dereference(rxqueue->rps_flow_table);
4653 if (flow_table && flow_id <= flow_table->mask) {
4654 rflow = &flow_table->flows[flow_id];
4655 cpu = READ_ONCE(rflow->cpu);
4656 if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
4657 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
4658 rflow->last_qtail) <
4659 (int)(10 * flow_table->mask)))
4660 expire = false;
4661 }
4662 rcu_read_unlock();
4663 return expire;
4664}
4665EXPORT_SYMBOL(rps_may_expire_flow);
4666
4667#endif /* CONFIG_RFS_ACCEL */
4668
4669/* Called from hardirq (IPI) context */
4670static void rps_trigger_softirq(void *data)
4671{
4672 struct softnet_data *sd = data;
4673
4674 ____napi_schedule(sd, napi: &sd->backlog);
4675 sd->received_rps++;
4676}
4677
4678#endif /* CONFIG_RPS */
4679
4680/* Called from hardirq (IPI) context */
4681static void trigger_rx_softirq(void *data)
4682{
4683 struct softnet_data *sd = data;
4684
4685 __raise_softirq_irqoff(nr: NET_RX_SOFTIRQ);
4686 smp_store_release(&sd->defer_ipi_scheduled, 0);
4687}
4688
4689/*
4690 * After we queued a packet into sd->input_pkt_queue,
4691 * we need to make sure this queue is serviced soon.
4692 *
4693 * - If this is another cpu queue, link it to our rps_ipi_list,
4694 * and make sure we will process rps_ipi_list from net_rx_action().
4695 *
4696 * - If this is our own queue, NAPI schedule our backlog.
4697 * Note that this also raises NET_RX_SOFTIRQ.
4698 */
4699static void napi_schedule_rps(struct softnet_data *sd)
4700{
4701 struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
4702
4703#ifdef CONFIG_RPS
4704 if (sd != mysd) {
4705 sd->rps_ipi_next = mysd->rps_ipi_list;
4706 mysd->rps_ipi_list = sd;
4707
4708 /* If not called from net_rx_action() or napi_threaded_poll()
4709 * we have to raise NET_RX_SOFTIRQ.
4710 */
4711 if (!mysd->in_net_rx_action && !mysd->in_napi_threaded_poll)
4712 __raise_softirq_irqoff(nr: NET_RX_SOFTIRQ);
4713 return;
4714 }
4715#endif /* CONFIG_RPS */
4716 __napi_schedule_irqoff(n: &mysd->backlog);
4717}
4718
4719#ifdef CONFIG_NET_FLOW_LIMIT
4720int netdev_flow_limit_table_len __read_mostly = (1 << 12);
4721#endif
4722
4723static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
4724{
4725#ifdef CONFIG_NET_FLOW_LIMIT
4726 struct sd_flow_limit *fl;
4727 struct softnet_data *sd;
4728 unsigned int old_flow, new_flow;
4729
4730 if (qlen < (READ_ONCE(netdev_max_backlog) >> 1))
4731 return false;
4732
4733 sd = this_cpu_ptr(&softnet_data);
4734
4735 rcu_read_lock();
4736 fl = rcu_dereference(sd->flow_limit);
4737 if (fl) {
4738 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
4739 old_flow = fl->history[fl->history_head];
4740 fl->history[fl->history_head] = new_flow;
4741
4742 fl->history_head++;
4743 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
4744
4745 if (likely(fl->buckets[old_flow]))
4746 fl->buckets[old_flow]--;
4747
4748 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
4749 fl->count++;
4750 rcu_read_unlock();
4751 return true;
4752 }
4753 }
4754 rcu_read_unlock();
4755#endif
4756 return false;
4757}
4758
4759/*
4760 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
4761 * queue (may be a remote CPU queue).
4762 */
4763static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
4764 unsigned int *qtail)
4765{
4766 enum skb_drop_reason reason;
4767 struct softnet_data *sd;
4768 unsigned long flags;
4769 unsigned int qlen;
4770
4771 reason = SKB_DROP_REASON_NOT_SPECIFIED;
4772 sd = &per_cpu(softnet_data, cpu);
4773
4774 rps_lock_irqsave(sd, flags: &flags);
4775 if (!netif_running(dev: skb->dev))
4776 goto drop;
4777 qlen = skb_queue_len(list_: &sd->input_pkt_queue);
4778 if (qlen <= READ_ONCE(netdev_max_backlog) && !skb_flow_limit(skb, qlen)) {
4779 if (qlen) {
4780enqueue:
4781 __skb_queue_tail(list: &sd->input_pkt_queue, newsk: skb);
4782 input_queue_tail_incr_save(sd, qtail);
4783 rps_unlock_irq_restore(sd, flags: &flags);
4784 return NET_RX_SUCCESS;
4785 }
4786
4787 /* Schedule NAPI for backlog device
4788 * We can use non atomic operation since we own the queue lock
4789 */
4790 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state))
4791 napi_schedule_rps(sd);
4792 goto enqueue;
4793 }
4794 reason = SKB_DROP_REASON_CPU_BACKLOG;
4795
4796drop:
4797 sd->dropped++;
4798 rps_unlock_irq_restore(sd, flags: &flags);
4799
4800 dev_core_stats_rx_dropped_inc(dev: skb->dev);
4801 kfree_skb_reason(skb, reason);
4802 return NET_RX_DROP;
4803}
4804
4805static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb)
4806{
4807 struct net_device *dev = skb->dev;
4808 struct netdev_rx_queue *rxqueue;
4809
4810 rxqueue = dev->_rx;
4811
4812 if (skb_rx_queue_recorded(skb)) {
4813 u16 index = skb_get_rx_queue(skb);
4814
4815 if (unlikely(index >= dev->real_num_rx_queues)) {
4816 WARN_ONCE(dev->real_num_rx_queues > 1,
4817 "%s received packet on queue %u, but number "
4818 "of RX queues is %u\n",
4819 dev->name, index, dev->real_num_rx_queues);
4820
4821 return rxqueue; /* Return first rxqueue */
4822 }
4823 rxqueue += index;
4824 }
4825 return rxqueue;
4826}
4827
4828u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
4829 struct bpf_prog *xdp_prog)
4830{
4831 void *orig_data, *orig_data_end, *hard_start;
4832 struct netdev_rx_queue *rxqueue;
4833 bool orig_bcast, orig_host;
4834 u32 mac_len, frame_sz;
4835 __be16 orig_eth_type;
4836 struct ethhdr *eth;
4837 u32 metalen, act;
4838 int off;
4839
4840 /* The XDP program wants to see the packet starting at the MAC
4841 * header.
4842 */
4843 mac_len = skb->data - skb_mac_header(skb);
4844 hard_start = skb->data - skb_headroom(skb);
4845
4846 /* SKB "head" area always have tailroom for skb_shared_info */
4847 frame_sz = (void *)skb_end_pointer(skb) - hard_start;
4848 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
4849
4850 rxqueue = netif_get_rxqueue(skb);
4851 xdp_init_buff(xdp, frame_sz, rxq: &rxqueue->xdp_rxq);
4852 xdp_prepare_buff(xdp, hard_start, headroom: skb_headroom(skb) - mac_len,
4853 data_len: skb_headlen(skb) + mac_len, meta_valid: true);
4854
4855 orig_data_end = xdp->data_end;
4856 orig_data = xdp->data;
4857 eth = (struct ethhdr *)xdp->data;
4858 orig_host = ether_addr_equal_64bits(addr1: eth->h_dest, addr2: skb->dev->dev_addr);
4859 orig_bcast = is_multicast_ether_addr_64bits(addr: eth->h_dest);
4860 orig_eth_type = eth->h_proto;
4861
4862 act = bpf_prog_run_xdp(prog: xdp_prog, xdp);
4863
4864 /* check if bpf_xdp_adjust_head was used */
4865 off = xdp->data - orig_data;
4866 if (off) {
4867 if (off > 0)
4868 __skb_pull(skb, len: off);
4869 else if (off < 0)
4870 __skb_push(skb, len: -off);
4871
4872 skb->mac_header += off;
4873 skb_reset_network_header(skb);
4874 }
4875
4876 /* check if bpf_xdp_adjust_tail was used */
4877 off = xdp->data_end - orig_data_end;
4878 if (off != 0) {
4879 skb_set_tail_pointer(skb, offset: xdp->data_end - xdp->data);
4880 skb->len += off; /* positive on grow, negative on shrink */
4881 }
4882
4883 /* check if XDP changed eth hdr such SKB needs update */
4884 eth = (struct ethhdr *)xdp->data;
4885 if ((orig_eth_type != eth->h_proto) ||
4886 (orig_host != ether_addr_equal_64bits(addr1: eth->h_dest,
4887 addr2: skb->dev->dev_addr)) ||
4888 (orig_bcast != is_multicast_ether_addr_64bits(addr: eth->h_dest))) {
4889 __skb_push(skb, ETH_HLEN);
4890 skb->pkt_type = PACKET_HOST;
4891 skb->protocol = eth_type_trans(skb, dev: skb->dev);
4892 }
4893
4894 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull
4895 * before calling us again on redirect path. We do not call do_redirect
4896 * as we leave that up to the caller.
4897 *
4898 * Caller is responsible for managing lifetime of skb (i.e. calling
4899 * kfree_skb in response to actions it cannot handle/XDP_DROP).
4900 */
4901 switch (act) {
4902 case XDP_REDIRECT:
4903 case XDP_TX:
4904 __skb_push(skb, len: mac_len);
4905 break;
4906 case XDP_PASS:
4907 metalen = xdp->data - xdp->data_meta;
4908 if (metalen)
4909 skb_metadata_set(skb, meta_len: metalen);
4910 break;
4911 }
4912
4913 return act;
4914}
4915
4916static u32 netif_receive_generic_xdp(struct sk_buff *skb,
4917 struct xdp_buff *xdp,
4918 struct bpf_prog *xdp_prog)
4919{
4920 u32 act = XDP_DROP;
4921
4922 /* Reinjected packets coming from act_mirred or similar should
4923 * not get XDP generic processing.
4924 */
4925 if (skb_is_redirected(skb))
4926 return XDP_PASS;
4927
4928 /* XDP packets must be linear and must have sufficient headroom
4929 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also
4930 * native XDP provides, thus we need to do it here as well.
4931 */
4932 if (skb_cloned(skb) || skb_is_nonlinear(skb) ||
4933 skb_headroom(skb) < XDP_PACKET_HEADROOM) {
4934 int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb);
4935 int troom = skb->tail + skb->data_len - skb->end;
4936
4937 /* In case we have to go down the path and also linearize,
4938 * then lets do the pskb_expand_head() work just once here.
4939 */
4940 if (pskb_expand_head(skb,
4941 nhead: hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0,
4942 ntail: troom > 0 ? troom + 128 : 0, GFP_ATOMIC))
4943 goto do_drop;
4944 if (skb_linearize(skb))
4945 goto do_drop;
4946 }
4947
4948 act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog);
4949 switch (act) {
4950 case XDP_REDIRECT:
4951 case XDP_TX:
4952 case XDP_PASS:
4953 break;
4954 default:
4955 bpf_warn_invalid_xdp_action(dev: skb->dev, prog: xdp_prog, act);
4956 fallthrough;
4957 case XDP_ABORTED:
4958 trace_xdp_exception(dev: skb->dev, xdp: xdp_prog, act);
4959 fallthrough;
4960 case XDP_DROP:
4961 do_drop:
4962 kfree_skb(skb);
4963 break;
4964 }
4965
4966 return act;
4967}
4968
4969/* When doing generic XDP we have to bypass the qdisc layer and the
4970 * network taps in order to match in-driver-XDP behavior. This also means
4971 * that XDP packets are able to starve other packets going through a qdisc,
4972 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX
4973 * queues, so they do not have this starvation issue.
4974 */
4975void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
4976{
4977 struct net_device *dev = skb->dev;
4978 struct netdev_queue *txq;
4979 bool free_skb = true;
4980 int cpu, rc;
4981
4982 txq = netdev_core_pick_tx(dev, skb, NULL);
4983 cpu = smp_processor_id();
4984 HARD_TX_LOCK(dev, txq, cpu);
4985 if (!netif_xmit_frozen_or_drv_stopped(dev_queue: txq)) {
4986 rc = netdev_start_xmit(skb, dev, txq, more: 0);
4987 if (dev_xmit_complete(rc))
4988 free_skb = false;
4989 }
4990 HARD_TX_UNLOCK(dev, txq);
4991 if (free_skb) {
4992 trace_xdp_exception(dev, xdp: xdp_prog, act: XDP_TX);
4993 dev_core_stats_tx_dropped_inc(dev);
4994 kfree_skb(skb);
4995 }
4996}
4997
4998static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key);
4999
5000int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb)
5001{
5002 if (xdp_prog) {
5003 struct xdp_buff xdp;
5004 u32 act;
5005 int err;
5006
5007 act = netif_receive_generic_xdp(skb, xdp: &xdp, xdp_prog);
5008 if (act != XDP_PASS) {
5009 switch (act) {
5010 case XDP_REDIRECT:
5011 err = xdp_do_generic_redirect(dev: skb->dev, skb,
5012 xdp: &xdp, prog: xdp_prog);
5013 if (err)
5014 goto out_redir;
5015 break;
5016 case XDP_TX:
5017 generic_xdp_tx(skb, xdp_prog);
5018 break;
5019 }
5020 return XDP_DROP;
5021 }
5022 }
5023 return XDP_PASS;
5024out_redir:
5025 kfree_skb_reason(skb, reason: SKB_DROP_REASON_XDP);
5026 return XDP_DROP;
5027}
5028EXPORT_SYMBOL_GPL(do_xdp_generic);
5029
5030static int netif_rx_internal(struct sk_buff *skb)
5031{
5032 int ret;
5033
5034 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
5035
5036 trace_netif_rx(skb);
5037
5038#ifdef CONFIG_RPS
5039 if (static_branch_unlikely(&rps_needed)) {
5040 struct rps_dev_flow voidflow, *rflow = &voidflow;
5041 int cpu;
5042
5043 rcu_read_lock();
5044
5045 cpu = get_rps_cpu(dev: skb->dev, skb, rflowp: &rflow);
5046 if (cpu < 0)
5047 cpu = smp_processor_id();
5048
5049 ret = enqueue_to_backlog(skb, cpu, qtail: &rflow->last_qtail);
5050
5051 rcu_read_unlock();
5052 } else
5053#endif
5054 {
5055 unsigned int qtail;
5056
5057 ret = enqueue_to_backlog(skb, smp_processor_id(), qtail: &qtail);
5058 }
5059 return ret;
5060}
5061
5062/**
5063 * __netif_rx - Slightly optimized version of netif_rx
5064 * @skb: buffer to post
5065 *
5066 * This behaves as netif_rx except that it does not disable bottom halves.
5067 * As a result this function may only be invoked from the interrupt context
5068 * (either hard or soft interrupt).
5069 */
5070int __netif_rx(struct sk_buff *skb)
5071{
5072 int ret;
5073
5074 lockdep_assert_once(hardirq_count() | softirq_count());
5075
5076 trace_netif_rx_entry(skb);
5077 ret = netif_rx_internal(skb);
5078 trace_netif_rx_exit(ret);
5079 return ret;
5080}
5081EXPORT_SYMBOL(__netif_rx);
5082
5083/**
5084 * netif_rx - post buffer to the network code
5085 * @skb: buffer to post
5086 *
5087 * This function receives a packet from a device driver and queues it for
5088 * the upper (protocol) levels to process via the backlog NAPI device. It
5089 * always succeeds. The buffer may be dropped during processing for
5090 * congestion control or by the protocol layers.
5091 * The network buffer is passed via the backlog NAPI device. Modern NIC
5092 * driver should use NAPI and GRO.
5093 * This function can used from interrupt and from process context. The
5094 * caller from process context must not disable interrupts before invoking
5095 * this function.
5096 *
5097 * return values:
5098 * NET_RX_SUCCESS (no congestion)
5099 * NET_RX_DROP (packet was dropped)
5100 *
5101 */
5102int netif_rx(struct sk_buff *skb)
5103{
5104 bool need_bh_off = !(hardirq_count() | softirq_count());
5105 int ret;
5106
5107 if (need_bh_off)
5108 local_bh_disable();
5109 trace_netif_rx_entry(skb);
5110 ret = netif_rx_internal(skb);
5111 trace_netif_rx_exit(ret);
5112 if (need_bh_off)
5113 local_bh_enable();
5114 return ret;
5115}
5116EXPORT_SYMBOL(netif_rx);
5117
5118static __latent_entropy void net_tx_action(struct softirq_action *h)
5119{
5120 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
5121
5122 if (sd->completion_queue) {
5123 struct sk_buff *clist;
5124
5125 local_irq_disable();
5126 clist = sd->completion_queue;
5127 sd->completion_queue = NULL;
5128 local_irq_enable();
5129
5130 while (clist) {
5131 struct sk_buff *skb = clist;
5132
5133 clist = clist->next;
5134
5135 WARN_ON(refcount_read(&skb->users));
5136 if (likely(get_kfree_skb_cb(skb)->reason == SKB_CONSUMED))
5137 trace_consume_skb(skb, location: net_tx_action);
5138 else
5139 trace_kfree_skb(skb, location: net_tx_action,
5140 reason: get_kfree_skb_cb(skb)->reason);
5141
5142 if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
5143 __kfree_skb(skb);
5144 else
5145 __napi_kfree_skb(skb,
5146 reason: get_kfree_skb_cb(skb)->reason);
5147 }
5148 }
5149
5150 if (sd->output_queue) {
5151 struct Qdisc *head;
5152
5153 local_irq_disable();
5154 head = sd->output_queue;
5155 sd->output_queue = NULL;
5156 sd->output_queue_tailp = &sd->output_queue;
5157 local_irq_enable();
5158
5159 rcu_read_lock();
5160
5161 while (head) {
5162 struct Qdisc *q = head;
5163 spinlock_t *root_lock = NULL;
5164
5165 head = head->next_sched;
5166
5167 /* We need to make sure head->next_sched is read
5168 * before clearing __QDISC_STATE_SCHED
5169 */
5170 smp_mb__before_atomic();
5171
5172 if (!(q->flags & TCQ_F_NOLOCK)) {
5173 root_lock = qdisc_lock(qdisc: q);
5174 spin_lock(lock: root_lock);
5175 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED,
5176 &q->state))) {
5177 /* There is a synchronize_net() between
5178 * STATE_DEACTIVATED flag being set and
5179 * qdisc_reset()/some_qdisc_is_busy() in
5180 * dev_deactivate(), so we can safely bail out
5181 * early here to avoid data race between
5182 * qdisc_deactivate() and some_qdisc_is_busy()
5183 * for lockless qdisc.
5184 */
5185 clear_bit(nr: __QDISC_STATE_SCHED, addr: &q->state);
5186 continue;
5187 }
5188
5189 clear_bit(nr: __QDISC_STATE_SCHED, addr: &q->state);
5190 qdisc_run(q);
5191 if (root_lock)
5192 spin_unlock(lock: root_lock);
5193 }
5194
5195 rcu_read_unlock();
5196 }
5197
5198 xfrm_dev_backlog(sd);
5199}
5200
5201#if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
5202/* This hook is defined here for ATM LANE */
5203int (*br_fdb_test_addr_hook)(struct net_device *dev,
5204 unsigned char *addr) __read_mostly;
5205EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
5206#endif
5207
5208/**
5209 * netdev_is_rx_handler_busy - check if receive handler is registered
5210 * @dev: device to check
5211 *
5212 * Check if a receive handler is already registered for a given device.
5213 * Return true if there one.
5214 *
5215 * The caller must hold the rtnl_mutex.
5216 */
5217bool netdev_is_rx_handler_busy(struct net_device *dev)
5218{
5219 ASSERT_RTNL();
5220 return dev && rtnl_dereference(dev->rx_handler);
5221}
5222EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);
5223
5224/**
5225 * netdev_rx_handler_register - register receive handler
5226 * @dev: device to register a handler for
5227 * @rx_handler: receive handler to register
5228 * @rx_handler_data: data pointer that is used by rx handler
5229 *
5230 * Register a receive handler for a device. This handler will then be
5231 * called from __netif_receive_skb. A negative errno code is returned
5232 * on a failure.
5233 *
5234 * The caller must hold the rtnl_mutex.
5235 *
5236 * For a general description of rx_handler, see enum rx_handler_result.
5237 */
5238int netdev_rx_handler_register(struct net_device *dev,
5239 rx_handler_func_t *rx_handler,
5240 void *rx_handler_data)
5241{
5242 if (netdev_is_rx_handler_busy(dev))
5243 return -EBUSY;
5244
5245 if (dev->priv_flags & IFF_NO_RX_HANDLER)
5246 return -EINVAL;
5247
5248 /* Note: rx_handler_data must be set before rx_handler */
5249 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
5250 rcu_assign_pointer(dev->rx_handler, rx_handler);
5251
5252 return 0;
5253}
5254EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
5255
5256/**
5257 * netdev_rx_handler_unregister - unregister receive handler
5258 * @dev: device to unregister a handler from
5259 *
5260 * Unregister a receive handler from a device.
5261 *
5262 * The caller must hold the rtnl_mutex.
5263 */
5264void netdev_rx_handler_unregister(struct net_device *dev)
5265{
5266
5267 ASSERT_RTNL();
5268 RCU_INIT_POINTER(dev->rx_handler, NULL);
5269 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
5270 * section has a guarantee to see a non NULL rx_handler_data
5271 * as well.
5272 */
5273 synchronize_net();
5274 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
5275}
5276EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
5277
5278/*
5279 * Limit the use of PFMEMALLOC reserves to those protocols that implement
5280 * the special handling of PFMEMALLOC skbs.
5281 */
5282static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
5283{
5284 switch (skb->protocol) {
5285 case htons(ETH_P_ARP):
5286 case htons(ETH_P_IP):
5287 case htons(ETH_P_IPV6):
5288 case htons(ETH_P_8021Q):
5289 case htons(ETH_P_8021AD):
5290 return true;
5291 default:
5292 return false;
5293 }
5294}
5295
5296static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
5297 int *ret, struct net_device *orig_dev)
5298{
5299 if (nf_hook_ingress_active(skb)) {
5300 int ingress_retval;
5301
5302 if (*pt_prev) {
5303 *ret = deliver_skb(skb, pt_prev: *pt_prev, orig_dev);
5304 *pt_prev = NULL;
5305 }
5306
5307 rcu_read_lock();
5308 ingress_retval = nf_hook_ingress(skb);
5309 rcu_read_unlock();
5310 return ingress_retval;
5311 }
5312 return 0;
5313}
5314
5315static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
5316 struct packet_type **ppt_prev)
5317{
5318 struct packet_type *ptype, *pt_prev;
5319 rx_handler_func_t *rx_handler;
5320 struct sk_buff *skb = *pskb;
5321 struct net_device *orig_dev;
5322 bool deliver_exact = false;
5323 int ret = NET_RX_DROP;
5324 __be16 type;
5325
5326 net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb);
5327
5328 trace_netif_receive_skb(skb);
5329
5330 orig_dev = skb->dev;
5331
5332 skb_reset_network_header(skb);
5333 if (!skb_transport_header_was_set(skb))
5334 skb_reset_transport_header(skb);
5335 skb_reset_mac_len(skb);
5336
5337 pt_prev = NULL;
5338
5339another_round:
5340 skb->skb_iif = skb->dev->ifindex;
5341
5342 __this_cpu_inc(softnet_data.processed);
5343
5344 if (static_branch_unlikely(&generic_xdp_needed_key)) {
5345 int ret2;
5346
5347 migrate_disable();
5348 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb);
5349 migrate_enable();
5350
5351 if (ret2 != XDP_PASS) {
5352 ret = NET_RX_DROP;
5353 goto out;
5354 }
5355 }
5356
5357 if (eth_type_vlan(ethertype: skb->protocol)) {
5358 skb = skb_vlan_untag(skb);
5359 if (unlikely(!skb))
5360 goto out;
5361 }
5362
5363 if (skb_skip_tc_classify(skb))
5364 goto skip_classify;
5365
5366 if (pfmemalloc)
5367 goto skip_taps;
5368
5369 list_for_each_entry_rcu(ptype, &ptype_all, list) {
5370 if (pt_prev)
5371 ret = deliver_skb(skb, pt_prev, orig_dev);
5372 pt_prev = ptype;
5373 }
5374
5375 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
5376 if (pt_prev)
5377 ret = deliver_skb(skb, pt_prev, orig_dev);
5378 pt_prev = ptype;
5379 }
5380
5381skip_taps:
5382#ifdef CONFIG_NET_INGRESS
5383 if (static_branch_unlikely(&ingress_needed_key)) {
5384 bool another = false;
5385
5386 nf_skip_egress(skb, skip: true);
5387 skb = sch_handle_ingress(skb, pt_prev: &pt_prev, ret: &ret, orig_dev,
5388 another: &another);
5389 if (another)
5390 goto another_round;
5391 if (!skb)
5392 goto out;
5393
5394 nf_skip_egress(skb, skip: false);
5395 if (nf_ingress(skb, pt_prev: &pt_prev, ret: &ret, orig_dev) < 0)
5396 goto out;
5397 }
5398#endif
5399 skb_reset_redirect(skb);
5400skip_classify:
5401 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
5402 goto drop;
5403
5404 if (skb_vlan_tag_present(skb)) {
5405 if (pt_prev) {
5406 ret = deliver_skb(skb, pt_prev, orig_dev);
5407 pt_prev = NULL;
5408 }
5409 if (vlan_do_receive(skb: &skb))
5410 goto another_round;
5411 else if (unlikely(!skb))
5412 goto out;
5413 }
5414
5415 rx_handler = rcu_dereference(skb->dev->rx_handler);
5416 if (rx_handler) {
5417 if (pt_prev) {
5418 ret = deliver_skb(skb, pt_prev, orig_dev);
5419 pt_prev = NULL;
5420 }
5421 switch (rx_handler(&skb)) {
5422 case RX_HANDLER_CONSUMED:
5423 ret = NET_RX_SUCCESS;
5424 goto out;
5425 case RX_HANDLER_ANOTHER:
5426 goto another_round;
5427 case RX_HANDLER_EXACT:
5428 deliver_exact = true;
5429 break;
5430 case RX_HANDLER_PASS:
5431 break;
5432 default:
5433 BUG();
5434 }
5435 }
5436
5437 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(dev: skb->dev)) {
5438check_vlan_id:
5439 if (skb_vlan_tag_get_id(skb)) {
5440 /* Vlan id is non 0 and vlan_do_receive() above couldn't
5441 * find vlan device.
5442 */
5443 skb->pkt_type = PACKET_OTHERHOST;
5444 } else if (eth_type_vlan(ethertype: skb->protocol)) {
5445 /* Outer header is 802.1P with vlan 0, inner header is
5446 * 802.1Q or 802.1AD and vlan_do_receive() above could
5447 * not find vlan dev for vlan id 0.
5448 */
5449 __vlan_hwaccel_clear_tag(skb);
5450 skb = skb_vlan_untag(skb);
5451 if (unlikely(!skb))
5452 goto out;
5453 if (vlan_do_receive(skb: &skb))
5454 /* After stripping off 802.1P header with vlan 0
5455 * vlan dev is found for inner header.
5456 */
5457 goto another_round;
5458 else if (unlikely(!skb))
5459 goto out;
5460 else
5461 /* We have stripped outer 802.1P vlan 0 header.
5462 * But could not find vlan dev.
5463 * check again for vlan id to set OTHERHOST.
5464 */
5465 goto check_vlan_id;
5466 }
5467 /* Note: we might in the future use prio bits
5468 * and set skb->priority like in vlan_do_receive()
5469 * For the time being, just ignore Priority Code Point
5470 */
5471 __vlan_hwaccel_clear_tag(skb);
5472 }
5473
5474 type = skb->protocol;
5475
5476 /* deliver only exact match when indicated */
5477 if (likely(!deliver_exact)) {
5478 deliver_ptype_list_skb(skb, pt: &pt_prev, orig_dev, type,
5479 ptype_list: &ptype_base[ntohs(type) &
5480 PTYPE_HASH_MASK]);
5481 }
5482
5483 deliver_ptype_list_skb(skb, pt: &pt_prev, orig_dev, type,
5484 ptype_list: &orig_dev->ptype_specific);
5485
5486 if (unlikely(skb->dev != orig_dev)) {
5487 deliver_ptype_list_skb(skb, pt: &pt_prev, orig_dev, type,
5488 ptype_list: &skb->dev->ptype_specific);
5489 }
5490
5491 if (pt_prev) {
5492 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
5493 goto drop;
5494 *ppt_prev = pt_prev;
5495 } else {
5496drop:
5497 if (!deliver_exact)
5498 dev_core_stats_rx_dropped_inc(dev: skb->dev);
5499 else
5500 dev_core_stats_rx_nohandler_inc(dev: skb->dev);
5501 kfree_skb_reason(skb, reason: SKB_DROP_REASON_UNHANDLED_PROTO);
5502 /* Jamal, now you will not able to escape explaining
5503 * me how you were going to use this. :-)
5504 */
5505 ret = NET_RX_DROP;
5506 }
5507
5508out:
5509 /* The invariant here is that if *ppt_prev is not NULL
5510 * then skb should also be non-NULL.
5511 *
5512 * Apparently *ppt_prev assignment above holds this invariant due to
5513 * skb dereferencing near it.
5514 */
5515 *pskb = skb;
5516 return ret;
5517}
5518
5519static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc)
5520{
5521 struct net_device *orig_dev = skb->dev;
5522 struct packet_type *pt_prev = NULL;
5523 int ret;
5524
5525 ret = __netif_receive_skb_core(pskb: &skb, pfmemalloc, ppt_prev: &pt_prev);
5526 if (pt_prev)
5527 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb,
5528 skb->dev, pt_prev, orig_dev);
5529 return ret;
5530}
5531
5532/**
5533 * netif_receive_skb_core - special purpose version of netif_receive_skb
5534 * @skb: buffer to process
5535 *
5536 * More direct receive version of netif_receive_skb(). It should
5537 * only be used by callers that have a need to skip RPS and Generic XDP.
5538 * Caller must also take care of handling if ``(page_is_)pfmemalloc``.
5539 *
5540 * This function may only be called from softirq context and interrupts
5541 * should be enabled.
5542 *
5543 * Return values (usually ignored):
5544 * NET_RX_SUCCESS: no congestion
5545 * NET_RX_DROP: packet was dropped
5546 */
5547int netif_receive_skb_core(struct sk_buff *skb)
5548{
5549 int ret;
5550
5551 rcu_read_lock();
5552 ret = __netif_receive_skb_one_core(skb, pfmemalloc: false);
5553 rcu_read_unlock();
5554
5555 return ret;
5556}
5557EXPORT_SYMBOL(netif_receive_skb_core);
5558
5559static inline void __netif_receive_skb_list_ptype(struct list_head *head,
5560 struct packet_type *pt_prev,
5561 struct net_device *orig_dev)
5562{
5563 struct sk_buff *skb, *next;
5564
5565 if (!pt_prev)
5566 return;
5567 if (list_empty(head))
5568 return;
5569 if (pt_prev->list_func != NULL)
5570 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv,
5571 ip_list_rcv, head, pt_prev, orig_dev);
5572 else
5573 list_for_each_entry_safe(skb, next, head, list) {
5574 skb_list_del_init(skb);
5575 pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
5576 }
5577}
5578
5579static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc)
5580{
5581 /* Fast-path assumptions:
5582 * - There is no RX handler.
5583 * - Only one packet_type matches.
5584 * If either of these fails, we will end up doing some per-packet
5585 * processing in-line, then handling the 'last ptype' for the whole
5586 * sublist. This can't cause out-of-order delivery to any single ptype,
5587 * because the 'last ptype' must be constant across the sublist, and all
5588 * other ptypes are handled per-packet.
5589 */
5590 /* Current (common) ptype of sublist */
5591 struct packet_type *pt_curr = NULL;
5592 /* Current (common) orig_dev of sublist */
5593 struct net_device *od_curr = NULL;
5594 struct list_head sublist;
5595 struct sk_buff *skb, *next;
5596
5597 INIT_LIST_HEAD(list: &sublist);
5598 list_for_each_entry_safe(skb, next, head, list) {
5599 struct net_device *orig_dev = skb->dev;
5600 struct packet_type *pt_prev = NULL;
5601
5602 skb_list_del_init(skb);
5603 __netif_receive_skb_core(pskb: &skb, pfmemalloc, ppt_prev: &pt_prev);
5604 if (!pt_prev)
5605 continue;
5606 if (pt_curr != pt_prev || od_curr != orig_dev) {
5607 /* dispatch old sublist */
5608 __netif_receive_skb_list_ptype(head: &sublist, pt_prev: pt_curr, orig_dev: od_curr);
5609 /* start new sublist */
5610 INIT_LIST_HEAD(list: &sublist);
5611 pt_curr = pt_prev;
5612 od_curr = orig_dev;
5613 }
5614 list_add_tail(new: &skb->list, head: &sublist);
5615 }
5616
5617 /* dispatch final sublist */
5618 __netif_receive_skb_list_ptype(head: &sublist, pt_prev: pt_curr, orig_dev: od_curr);
5619}
5620
5621static int __netif_receive_skb(struct sk_buff *skb)
5622{
5623 int ret;
5624
5625 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
5626 unsigned int noreclaim_flag;
5627
5628 /*
5629 * PFMEMALLOC skbs are special, they should
5630 * - be delivered to SOCK_MEMALLOC sockets only
5631 * - stay away from userspace
5632 * - have bounded memory usage
5633 *
5634 * Use PF_MEMALLOC as this saves us from propagating the allocation
5635 * context down to all allocation sites.
5636 */
5637 noreclaim_flag = memalloc_noreclaim_save();
5638 ret = __netif_receive_skb_one_core(skb, pfmemalloc: true);
5639 memalloc_noreclaim_restore(flags: noreclaim_flag);
5640 } else
5641 ret = __netif_receive_skb_one_core(skb, pfmemalloc: false);
5642
5643 return ret;
5644}
5645
5646static void __netif_receive_skb_list(struct list_head *head)
5647{
5648 unsigned long noreclaim_flag = 0;
5649 struct sk_buff *skb, *next;
5650 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */
5651
5652 list_for_each_entry_safe(skb, next, head, list) {
5653 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) {
5654 struct list_head sublist;
5655
5656 /* Handle the previous sublist */
5657 list_cut_before(list: &sublist, head, entry: &skb->list);
5658 if (!list_empty(head: &sublist))
5659 __netif_receive_skb_list_core(head: &sublist, pfmemalloc);
5660 pfmemalloc = !pfmemalloc;
5661 /* See comments in __netif_receive_skb */
5662 if (pfmemalloc)
5663 noreclaim_flag = memalloc_noreclaim_save();
5664 else
5665 memalloc_noreclaim_restore(flags: noreclaim_flag);
5666 }
5667 }
5668 /* Handle the remaining sublist */
5669 if (!list_empty(head))
5670 __netif_receive_skb_list_core(head, pfmemalloc);
5671 /* Restore pflags */
5672 if (pfmemalloc)
5673 memalloc_noreclaim_restore(flags: noreclaim_flag);
5674}
5675
5676static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp)
5677{
5678 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog);
5679 struct bpf_prog *new = xdp->prog;
5680 int ret = 0;
5681
5682 switch (xdp->command) {
5683 case XDP_SETUP_PROG:
5684 rcu_assign_pointer(dev->xdp_prog, new);
5685 if (old)
5686 bpf_prog_put(prog: old);
5687
5688 if (old && !new) {
5689 static_branch_dec(&generic_xdp_needed_key);
5690 } else if (new && !old) {
5691 static_branch_inc(&generic_xdp_needed_key);
5692 dev_disable_lro(dev);
5693 dev_disable_gro_hw(dev);
5694 }
5695 break;
5696
5697 default:
5698 ret = -EINVAL;
5699 break;
5700 }
5701
5702 return ret;
5703}
5704
5705static int netif_receive_skb_internal(struct sk_buff *skb)
5706{
5707 int ret;
5708
5709 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
5710
5711 if (skb_defer_rx_timestamp(skb))
5712 return NET_RX_SUCCESS;
5713
5714 rcu_read_lock();
5715#ifdef CONFIG_RPS
5716 if (static_branch_unlikely(&rps_needed)) {
5717 struct rps_dev_flow voidflow, *rflow = &voidflow;
5718 int cpu = get_rps_cpu(dev: skb->dev, skb, rflowp: &rflow);
5719
5720 if (cpu >= 0) {
5721 ret = enqueue_to_backlog(skb, cpu, qtail: &rflow->last_qtail);
5722 rcu_read_unlock();
5723 return ret;
5724 }
5725 }
5726#endif
5727 ret = __netif_receive_skb(skb);
5728 rcu_read_unlock();
5729 return ret;
5730}
5731
5732void netif_receive_skb_list_internal(struct list_head *head)
5733{
5734 struct sk_buff *skb, *next;
5735 struct list_head sublist;
5736
5737 INIT_LIST_HEAD(list: &sublist);
5738 list_for_each_entry_safe(skb, next, head, list) {
5739 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
5740 skb_list_del_init(skb);
5741 if (!skb_defer_rx_timestamp(skb))
5742 list_add_tail(new: &skb->list, head: &sublist);
5743 }
5744 list_splice_init(list: &sublist, head);
5745
5746 rcu_read_lock();
5747#ifdef CONFIG_RPS
5748 if (static_branch_unlikely(&rps_needed)) {
5749 list_for_each_entry_safe(skb, next, head, list) {
5750 struct rps_dev_flow voidflow, *rflow = &voidflow;
5751 int cpu = get_rps_cpu(dev: skb->dev, skb, rflowp: &rflow);
5752
5753 if (cpu >= 0) {
5754 /* Will be handled, remove from list */
5755 skb_list_del_init(skb);
5756 enqueue_to_backlog(skb, cpu, qtail: &rflow->last_qtail);
5757 }
5758 }
5759 }
5760#endif
5761 __netif_receive_skb_list(head);
5762 rcu_read_unlock();
5763}
5764
5765/**
5766 * netif_receive_skb - process receive buffer from network
5767 * @skb: buffer to process
5768 *
5769 * netif_receive_skb() is the main receive data processing function.
5770 * It always succeeds. The buffer may be dropped during processing
5771 * for congestion control or by the protocol layers.
5772 *
5773 * This function may only be called from softirq context and interrupts
5774 * should be enabled.
5775 *
5776 * Return values (usually ignored):
5777 * NET_RX_SUCCESS: no congestion
5778 * NET_RX_DROP: packet was dropped
5779 */
5780int netif_receive_skb(struct sk_buff *skb)
5781{
5782 int ret;
5783
5784 trace_netif_receive_skb_entry(skb);
5785
5786 ret = netif_receive_skb_internal(skb);
5787 trace_netif_receive_skb_exit(ret);
5788
5789 return ret;
5790}
5791EXPORT_SYMBOL(netif_receive_skb);
5792
5793/**
5794 * netif_receive_skb_list - process many receive buffers from network
5795 * @head: list of skbs to process.
5796 *
5797 * Since return value of netif_receive_skb() is normally ignored, and
5798 * wouldn't be meaningful for a list, this function returns void.
5799 *
5800 * This function may only be called from softirq context and interrupts
5801 * should be enabled.
5802 */
5803void netif_receive_skb_list(struct list_head *head)
5804{
5805 struct sk_buff *skb;
5806
5807 if (list_empty(head))
5808 return;
5809 if (trace_netif_receive_skb_list_entry_enabled()) {
5810 list_for_each_entry(skb, head, list)
5811 trace_netif_receive_skb_list_entry(skb);
5812 }
5813 netif_receive_skb_list_internal(head);
5814 trace_netif_receive_skb_list_exit(ret: 0);
5815}
5816EXPORT_SYMBOL(netif_receive_skb_list);
5817
5818static DEFINE_PER_CPU(struct work_struct, flush_works);
5819
5820/* Network device is going away, flush any packets still pending */
5821static void flush_backlog(struct work_struct *work)
5822{
5823 struct sk_buff *skb, *tmp;
5824 struct softnet_data *sd;
5825
5826 local_bh_disable();
5827 sd = this_cpu_ptr(&softnet_data);
5828
5829 rps_lock_irq_disable(sd);
5830 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
5831 if (skb->dev->reg_state == NETREG_UNREGISTERING) {
5832 __skb_unlink(skb, list: &sd->input_pkt_queue);
5833 dev_kfree_skb_irq(skb);
5834 input_queue_head_incr(sd);
5835 }
5836 }
5837 rps_unlock_irq_enable(sd);
5838
5839 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
5840 if (skb->dev->reg_state == NETREG_UNREGISTERING) {
5841 __skb_unlink(skb, list: &sd->process_queue);
5842 kfree_skb(skb);
5843 input_queue_head_incr(sd);
5844 }
5845 }
5846 local_bh_enable();
5847}
5848
5849static bool flush_required(int cpu)
5850{
5851#if IS_ENABLED(CONFIG_RPS)
5852 struct softnet_data *sd = &per_cpu(softnet_data, cpu);
5853 bool do_flush;
5854
5855 rps_lock_irq_disable(sd);
5856
5857 /* as insertion into process_queue happens with the rps lock held,
5858 * process_queue access may race only with dequeue
5859 */
5860 do_flush = !skb_queue_empty(list: &sd->input_pkt_queue) ||
5861 !skb_queue_empty_lockless(list: &sd->process_queue);
5862 rps_unlock_irq_enable(sd);
5863
5864 return do_flush;
5865#endif
5866 /* without RPS we can't safely check input_pkt_queue: during a
5867 * concurrent remote skb_queue_splice() we can detect as empty both
5868 * input_pkt_queue and process_queue even if the latter could end-up
5869 * containing a lot of packets.
5870 */
5871 return true;
5872}
5873
5874static void flush_all_backlogs(void)
5875{
5876 static cpumask_t flush_cpus;
5877 unsigned int cpu;
5878
5879 /* since we are under rtnl lock protection we can use static data
5880 * for the cpumask and avoid allocating on stack the possibly
5881 * large mask
5882 */
5883 ASSERT_RTNL();
5884
5885 cpus_read_lock();
5886
5887 cpumask_clear(dstp: &flush_cpus);
5888 for_each_online_cpu(cpu) {
5889 if (flush_required(cpu)) {
5890 queue_work_on(cpu, wq: system_highpri_wq,
5891 per_cpu_ptr(&flush_works, cpu));
5892 cpumask_set_cpu(cpu, dstp: &flush_cpus);
5893 }
5894 }
5895
5896 /* we can have in flight packet[s] on the cpus we are not flushing,
5897 * synchronize_net() in unregister_netdevice_many() will take care of
5898 * them
5899 */
5900 for_each_cpu(cpu, &flush_cpus)
5901 flush_work(per_cpu_ptr(&flush_works, cpu));
5902
5903 cpus_read_unlock();
5904}
5905
5906static void net_rps_send_ipi(struct softnet_data *remsd)
5907{
5908#ifdef CONFIG_RPS
5909 while (remsd) {
5910 struct softnet_data *next = remsd->rps_ipi_next;
5911
5912 if (cpu_online(cpu: remsd->cpu))
5913 smp_call_function_single_async(cpu: remsd->cpu, csd: &remsd->csd);
5914 remsd = next;
5915 }
5916#endif
5917}
5918
5919/*
5920 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
5921 * Note: called with local irq disabled, but exits with local irq enabled.
5922 */
5923static void net_rps_action_and_irq_enable(struct softnet_data *sd)
5924{
5925#ifdef CONFIG_RPS
5926 struct softnet_data *remsd = sd->rps_ipi_list;
5927
5928 if (remsd) {
5929 sd->rps_ipi_list = NULL;
5930
5931 local_irq_enable();
5932
5933 /* Send pending IPI's to kick RPS processing on remote cpus. */
5934 net_rps_send_ipi(remsd);
5935 } else
5936#endif
5937 local_irq_enable();
5938}
5939
5940static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
5941{
5942#ifdef CONFIG_RPS
5943 return sd->rps_ipi_list != NULL;
5944#else
5945 return false;
5946#endif
5947}
5948
5949static int process_backlog(struct napi_struct *napi, int quota)
5950{
5951 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
5952 bool again = true;
5953 int work = 0;
5954
5955 /* Check if we have pending ipi, its better to send them now,
5956 * not waiting net_rx_action() end.
5957 */
5958 if (sd_has_rps_ipi_waiting(sd)) {
5959 local_irq_disable();
5960 net_rps_action_and_irq_enable(sd);
5961 }
5962
5963 napi->weight = READ_ONCE(dev_rx_weight);
5964 while (again) {
5965 struct sk_buff *skb;
5966
5967 while ((skb = __skb_dequeue(list: &sd->process_queue))) {
5968 rcu_read_lock();
5969 __netif_receive_skb(skb);
5970 rcu_read_unlock();
5971 input_queue_head_incr(sd);
5972 if (++work >= quota)
5973 return work;
5974
5975 }
5976
5977 rps_lock_irq_disable(sd);
5978 if (skb_queue_empty(list: &sd->input_pkt_queue)) {
5979 /*
5980 * Inline a custom version of __napi_complete().
5981 * only current cpu owns and manipulates this napi,
5982 * and NAPI_STATE_SCHED is the only possible flag set
5983 * on backlog.
5984 * We can use a plain write instead of clear_bit(),
5985 * and we dont need an smp_mb() memory barrier.
5986 */
5987 napi->state = 0;
5988 again = false;
5989 } else {
5990 skb_queue_splice_tail_init(list: &sd->input_pkt_queue,
5991 head: &sd->process_queue);
5992 }
5993 rps_unlock_irq_enable(sd);
5994 }
5995
5996 return work;
5997}
5998
5999/**
6000 * __napi_schedule - schedule for receive
6001 * @n: entry to schedule
6002 *
6003 * The entry's receive function will be scheduled to run.
6004 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
6005 */
6006void __napi_schedule(struct napi_struct *n)
6007{
6008 unsigned long flags;
6009
6010 local_irq_save(flags);
6011 ____napi_schedule(this_cpu_ptr(&softnet_data), napi: n);
6012 local_irq_restore(flags);
6013}
6014EXPORT_SYMBOL(__napi_schedule);
6015
6016/**
6017 * napi_schedule_prep - check if napi can be scheduled
6018 * @n: napi context
6019 *
6020 * Test if NAPI routine is already running, and if not mark
6021 * it as running. This is used as a condition variable to
6022 * insure only one NAPI poll instance runs. We also make
6023 * sure there is no pending NAPI disable.
6024 */
6025bool napi_schedule_prep(struct napi_struct *n)
6026{
6027 unsigned long new, val = READ_ONCE(n->state);
6028
6029 do {
6030 if (unlikely(val & NAPIF_STATE_DISABLE))
6031 return false;
6032 new = val | NAPIF_STATE_SCHED;
6033
6034 /* Sets STATE_MISSED bit if STATE_SCHED was already set
6035 * This was suggested by Alexander Duyck, as compiler
6036 * emits better code than :
6037 * if (val & NAPIF_STATE_SCHED)
6038 * new |= NAPIF_STATE_MISSED;
6039 */
6040 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED *
6041 NAPIF_STATE_MISSED;
6042 } while (!try_cmpxchg(&n->state, &val, new));
6043
6044 return !(val & NAPIF_STATE_SCHED);
6045}
6046EXPORT_SYMBOL(napi_schedule_prep);
6047
6048/**
6049 * __napi_schedule_irqoff - schedule for receive
6050 * @n: entry to schedule
6051 *
6052 * Variant of __napi_schedule() assuming hard irqs are masked.
6053 *
6054 * On PREEMPT_RT enabled kernels this maps to __napi_schedule()
6055 * because the interrupt disabled assumption might not be true
6056 * due to force-threaded interrupts and spinlock substitution.
6057 */
6058void __napi_schedule_irqoff(struct napi_struct *n)
6059{
6060 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
6061 ____napi_schedule(this_cpu_ptr(&softnet_data), napi: n);
6062 else
6063 __napi_schedule(n);
6064}
6065EXPORT_SYMBOL(__napi_schedule_irqoff);
6066
6067bool napi_complete_done(struct napi_struct *n, int work_done)
6068{
6069 unsigned long flags, val, new, timeout = 0;
6070 bool ret = true;
6071
6072 /*
6073 * 1) Don't let napi dequeue from the cpu poll list
6074 * just in case its running on a different cpu.
6075 * 2) If we are busy polling, do nothing here, we have
6076 * the guarantee we will be called later.
6077 */
6078 if (unlikely(n->state & (NAPIF_STATE_NPSVC |
6079 NAPIF_STATE_IN_BUSY_POLL)))
6080 return false;
6081
6082 if (work_done) {
6083 if (n->gro_bitmask)
6084 timeout = READ_ONCE(n->dev->gro_flush_timeout);
6085 n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs);
6086 }
6087 if (n->defer_hard_irqs_count > 0) {
6088 n->defer_hard_irqs_count--;
6089 timeout = READ_ONCE(n->dev->gro_flush_timeout);
6090 if (timeout)
6091 ret = false;
6092 }
6093 if (n->gro_bitmask) {
6094 /* When the NAPI instance uses a timeout and keeps postponing
6095 * it, we need to bound somehow the time packets are kept in
6096 * the GRO layer
6097 */
6098 napi_gro_flush(napi: n, flush_old: !!timeout);
6099 }
6100
6101 gro_normal_list(napi: n);
6102
6103 if (unlikely(!list_empty(&n->poll_list))) {
6104 /* If n->poll_list is not empty, we need to mask irqs */
6105 local_irq_save(flags);
6106 list_del_init(entry: &n->poll_list);
6107 local_irq_restore(flags);
6108 }
6109 WRITE_ONCE(n->list_owner, -1);
6110
6111 val = READ_ONCE(n->state);
6112 do {
6113 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED));
6114
6115 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED |
6116 NAPIF_STATE_SCHED_THREADED |
6117 NAPIF_STATE_PREFER_BUSY_POLL);
6118
6119 /* If STATE_MISSED was set, leave STATE_SCHED set,
6120 * because we will call napi->poll() one more time.
6121 * This C code was suggested by Alexander Duyck to help gcc.
6122 */
6123 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED *
6124 NAPIF_STATE_SCHED;
6125 } while (!try_cmpxchg(&n->state, &val, new));
6126
6127 if (unlikely(val & NAPIF_STATE_MISSED)) {
6128 __napi_schedule(n);
6129 return false;
6130 }
6131
6132 if (timeout)
6133 hrtimer_start(timer: &n->timer, tim: ns_to_ktime(ns: timeout),
6134 mode: HRTIMER_MODE_REL_PINNED);
6135 return ret;
6136}
6137EXPORT_SYMBOL(napi_complete_done);
6138
6139/* must be called under rcu_read_lock(), as we dont take a reference */
6140static struct napi_struct *napi_by_id(unsigned int napi_id)
6141{
6142 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
6143 struct napi_struct *napi;
6144
6145 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
6146 if (napi->napi_id == napi_id)
6147 return napi;
6148
6149 return NULL;
6150}
6151
6152#if defined(CONFIG_NET_RX_BUSY_POLL)
6153
6154static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule)
6155{
6156 if (!skip_schedule) {
6157 gro_normal_list(napi);
6158 __napi_schedule(napi);
6159 return;
6160 }
6161
6162 if (napi->gro_bitmask) {
6163 /* flush too old packets
6164 * If HZ < 1000, flush all packets.
6165 */
6166 napi_gro_flush(napi, HZ >= 1000);
6167 }
6168
6169 gro_normal_list(napi);
6170 clear_bit(nr: NAPI_STATE_SCHED, addr: &napi->state);
6171}
6172
6173static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, bool prefer_busy_poll,
6174 u16 budget)
6175{
6176 bool skip_schedule = false;
6177 unsigned long timeout;
6178 int rc;
6179
6180 /* Busy polling means there is a high chance device driver hard irq
6181 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was
6182 * set in napi_schedule_prep().
6183 * Since we are about to call napi->poll() once more, we can safely
6184 * clear NAPI_STATE_MISSED.
6185 *
6186 * Note: x86 could use a single "lock and ..." instruction
6187 * to perform these two clear_bit()
6188 */
6189 clear_bit(nr: NAPI_STATE_MISSED, addr: &napi->state);
6190 clear_bit(nr: NAPI_STATE_IN_BUSY_POLL, addr: &napi->state);
6191
6192 local_bh_disable();
6193
6194 if (prefer_busy_poll) {
6195 napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs);
6196 timeout = READ_ONCE(napi->dev->gro_flush_timeout);
6197 if (napi->defer_hard_irqs_count && timeout) {
6198 hrtimer_start(timer: &napi->timer, tim: ns_to_ktime(ns: timeout), mode: HRTIMER_MODE_REL_PINNED);
6199 skip_schedule = true;
6200 }
6201 }
6202
6203 /* All we really want here is to re-enable device interrupts.
6204 * Ideally, a new ndo_busy_poll_stop() could avoid another round.
6205 */
6206 rc = napi->poll(napi, budget);
6207 /* We can't gro_normal_list() here, because napi->poll() might have
6208 * rearmed the napi (napi_complete_done()) in which case it could
6209 * already be running on another CPU.
6210 */
6211 trace_napi_poll(napi, work: rc, budget);
6212 netpoll_poll_unlock(have: have_poll_lock);
6213 if (rc == budget)
6214 __busy_poll_stop(napi, skip_schedule);
6215 local_bh_enable();
6216}
6217
6218void napi_busy_loop(unsigned int napi_id,
6219 bool (*loop_end)(void *, unsigned long),
6220 void *loop_end_arg, bool prefer_busy_poll, u16 budget)
6221{
6222 unsigned long start_time = loop_end ? busy_loop_current_time() : 0;
6223 int (*napi_poll)(struct napi_struct *napi, int budget);
6224 void *have_poll_lock = NULL;
6225 struct napi_struct *napi;
6226
6227restart:
6228 napi_poll = NULL;
6229
6230 rcu_read_lock();
6231
6232 napi = napi_by_id(napi_id);
6233 if (!napi)
6234 goto out;
6235
6236 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
6237 preempt_disable();
6238 for (;;) {
6239 int work = 0;
6240
6241 local_bh_disable();
6242 if (!napi_poll) {
6243 unsigned long val = READ_ONCE(napi->state);
6244
6245 /* If multiple threads are competing for this napi,
6246 * we avoid dirtying napi->state as much as we can.
6247 */
6248 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED |
6249 NAPIF_STATE_IN_BUSY_POLL)) {
6250 if (prefer_busy_poll)
6251 set_bit(nr: NAPI_STATE_PREFER_BUSY_POLL, addr: &napi->state);
6252 goto count;
6253 }
6254 if (cmpxchg(&napi->state, val,
6255 val | NAPIF_STATE_IN_BUSY_POLL |
6256 NAPIF_STATE_SCHED) != val) {
6257 if (prefer_busy_poll)
6258 set_bit(nr: NAPI_STATE_PREFER_BUSY_POLL, addr: &napi->state);
6259 goto count;
6260 }
6261 have_poll_lock = netpoll_poll_lock(napi);
6262 napi_poll = napi->poll;
6263 }
6264 work = napi_poll(napi, budget);
6265 trace_napi_poll(napi, work, budget);
6266 gro_normal_list(napi);
6267count:
6268 if (work > 0)
6269 __NET_ADD_STATS(dev_net(napi->dev),
6270 LINUX_MIB_BUSYPOLLRXPACKETS, work);
6271 local_bh_enable();
6272
6273 if (!loop_end || loop_end(loop_end_arg, start_time))
6274 break;
6275
6276 if (unlikely(need_resched())) {
6277 if (napi_poll)
6278 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget);
6279 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
6280 preempt_enable();
6281 rcu_read_unlock();
6282 cond_resched();
6283 if (loop_end(loop_end_arg, start_time))
6284 return;
6285 goto restart;
6286 }
6287 cpu_relax();
6288 }
6289 if (napi_poll)
6290 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget);
6291 if (!IS_ENABLED(CONFIG_PREEMPT_RT))
6292 preempt_enable();
6293out:
6294 rcu_read_unlock();
6295}
6296EXPORT_SYMBOL(napi_busy_loop);
6297
6298#endif /* CONFIG_NET_RX_BUSY_POLL */
6299
6300static void napi_hash_add(struct napi_struct *napi)
6301{
6302 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state))
6303 return;
6304
6305 spin_lock(lock: &napi_hash_lock);
6306
6307 /* 0..NR_CPUS range is reserved for sender_cpu use */
6308 do {
6309 if (unlikely(++napi_gen_id < MIN_NAPI_ID))
6310 napi_gen_id = MIN_NAPI_ID;
6311 } while (napi_by_id(napi_id: napi_gen_id));
6312 napi->napi_id = napi_gen_id;
6313
6314 hlist_add_head_rcu(n: &napi->napi_hash_node,
6315 h: &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
6316
6317 spin_unlock(lock: &napi_hash_lock);
6318}
6319
6320/* Warning : caller is responsible to make sure rcu grace period
6321 * is respected before freeing memory containing @napi
6322 */
6323static void napi_hash_del(struct napi_struct *napi)
6324{
6325 spin_lock(lock: &napi_hash_lock);
6326
6327 hlist_del_init_rcu(n: &napi->napi_hash_node);
6328
6329 spin_unlock(lock: &napi_hash_lock);
6330}
6331
6332static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
6333{
6334 struct napi_struct *napi;
6335
6336 napi = container_of(timer, struct napi_struct, timer);
6337
6338 /* Note : we use a relaxed variant of napi_schedule_prep() not setting
6339 * NAPI_STATE_MISSED, since we do not react to a device IRQ.
6340 */
6341 if (!napi_disable_pending(n: napi) &&
6342 !test_and_set_bit(nr: NAPI_STATE_SCHED, addr: &napi->state)) {
6343 clear_bit(nr: NAPI_STATE_PREFER_BUSY_POLL, addr: &napi->state);
6344 __napi_schedule_irqoff(napi);
6345 }
6346
6347 return HRTIMER_NORESTART;
6348}
6349
6350static void init_gro_hash(struct napi_struct *napi)
6351{
6352 int i;
6353
6354 for (i = 0; i < GRO_HASH_BUCKETS; i++) {
6355 INIT_LIST_HEAD(list: &napi->gro_hash[i].list);
6356 napi->gro_hash[i].count = 0;
6357 }
6358 napi->gro_bitmask = 0;
6359}
6360
6361int dev_set_threaded(struct net_device *dev, bool threaded)
6362{
6363 struct napi_struct *napi;
6364 int err = 0;
6365
6366 if (dev->threaded == threaded)
6367 return 0;
6368
6369 if (threaded) {
6370 list_for_each_entry(napi, &dev->napi_list, dev_list) {
6371 if (!napi->thread) {
6372 err = napi_kthread_create(n: napi);
6373 if (err) {
6374 threaded = false;
6375 break;
6376 }
6377 }
6378 }
6379 }
6380
6381 dev->threaded = threaded;
6382
6383 /* Make sure kthread is created before THREADED bit
6384 * is set.
6385 */
6386 smp_mb__before_atomic();
6387
6388 /* Setting/unsetting threaded mode on a napi might not immediately
6389 * take effect, if the current napi instance is actively being
6390 * polled. In this case, the switch between threaded mode and
6391 * softirq mode will happen in the next round of napi_schedule().
6392 * This should not cause hiccups/stalls to the live traffic.
6393 */
6394 list_for_each_entry(napi, &dev->napi_list, dev_list)
6395 assign_bit(nr: NAPI_STATE_THREADED, addr: &napi->state, value: threaded);
6396
6397 return err;
6398}
6399EXPORT_SYMBOL(dev_set_threaded);
6400
6401void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi,
6402 int (*poll)(struct napi_struct *, int), int weight)
6403{
6404 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state)))
6405 return;
6406
6407 INIT_LIST_HEAD(list: &napi->poll_list);
6408 INIT_HLIST_NODE(h: &napi->napi_hash_node);
6409 hrtimer_init(timer: &napi->timer, CLOCK_MONOTONIC, mode: HRTIMER_MODE_REL_PINNED);
6410 napi->timer.function = napi_watchdog;
6411 init_gro_hash(napi);
6412 napi->skb = NULL;
6413 INIT_LIST_HEAD(list: &napi->rx_list);
6414 napi->rx_count = 0;
6415 napi->poll = poll;
6416 if (weight > NAPI_POLL_WEIGHT)
6417 netdev_err_once(dev, "%s() called with weight %d\n", __func__,
6418 weight);
6419 napi->weight = weight;
6420 napi->dev = dev;
6421#ifdef CONFIG_NETPOLL
6422 napi->poll_owner = -1;
6423#endif
6424 napi->list_owner = -1;
6425 set_bit(nr: NAPI_STATE_SCHED, addr: &napi->state);
6426 set_bit(nr: NAPI_STATE_NPSVC, addr: &napi->state);
6427 list_add_rcu(new: &napi->dev_list, head: &dev->napi_list);
6428 napi_hash_add(napi);
6429 napi_get_frags_check(napi);
6430 /* Create kthread for this napi if dev->threaded is set.
6431 * Clear dev->threaded if kthread creation failed so that
6432 * threaded mode will not be enabled in napi_enable().
6433 */
6434 if (dev->threaded && napi_kthread_create(n: napi))
6435 dev->threaded = 0;
6436}
6437EXPORT_SYMBOL(netif_napi_add_weight);
6438
6439void napi_disable(struct napi_struct *n)
6440{
6441 unsigned long val, new;
6442
6443 might_sleep();
6444 set_bit(nr: NAPI_STATE_DISABLE, addr: &n->state);
6445
6446 val = READ_ONCE(n->state);
6447 do {
6448 while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) {
6449 usleep_range(min: 20, max: 200);
6450 val = READ_ONCE(n->state);
6451 }
6452
6453 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC;
6454 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL);
6455 } while (!try_cmpxchg(&n->state, &val, new));
6456
6457 hrtimer_cancel(timer: &n->timer);
6458
6459 clear_bit(nr: NAPI_STATE_DISABLE, addr: &n->state);
6460}
6461EXPORT_SYMBOL(napi_disable);
6462
6463/**
6464 * napi_enable - enable NAPI scheduling
6465 * @n: NAPI context
6466 *
6467 * Resume NAPI from being scheduled on this context.
6468 * Must be paired with napi_disable.
6469 */
6470void napi_enable(struct napi_struct *n)
6471{
6472 unsigned long new, val = READ_ONCE(n->state);
6473
6474 do {
6475 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val));
6476
6477 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC);
6478 if (n->dev->threaded && n->thread)
6479 new |= NAPIF_STATE_THREADED;
6480 } while (!try_cmpxchg(&n->state, &val, new));
6481}
6482EXPORT_SYMBOL(napi_enable);
6483
6484static void flush_gro_hash(struct napi_struct *napi)
6485{
6486 int i;
6487
6488 for (i = 0; i < GRO_HASH_BUCKETS; i++) {
6489 struct sk_buff *skb, *n;
6490
6491 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list)
6492 kfree_skb(skb);
6493 napi->gro_hash[i].count = 0;
6494 }
6495}
6496
6497/* Must be called in process context */
6498void __netif_napi_del(struct napi_struct *napi)
6499{
6500 if (!test_and_clear_bit(nr: NAPI_STATE_LISTED, addr: &napi->state))
6501 return;
6502
6503 napi_hash_del(napi);
6504 list_del_rcu(entry: &napi->dev_list);
6505 napi_free_frags(napi);
6506
6507 flush_gro_hash(napi);
6508 napi->gro_bitmask = 0;
6509
6510 if (napi->thread) {
6511 kthread_stop(k: napi->thread);
6512 napi->thread = NULL;
6513 }
6514}
6515EXPORT_SYMBOL(__netif_napi_del);
6516
6517static int __napi_poll(struct napi_struct *n, bool *repoll)
6518{
6519 int work, weight;
6520
6521 weight = n->weight;
6522
6523 /* This NAPI_STATE_SCHED test is for avoiding a race
6524 * with netpoll's poll_napi(). Only the entity which
6525 * obtains the lock and sees NAPI_STATE_SCHED set will
6526 * actually make the ->poll() call. Therefore we avoid
6527 * accidentally calling ->poll() when NAPI is not scheduled.
6528 */
6529 work = 0;
6530 if (napi_is_scheduled(n)) {
6531 work = n->poll(n, weight);
6532 trace_napi_poll(napi: n, work, budget: weight);
6533
6534 xdp_do_check_flushed(napi: n);
6535 }
6536
6537 if (unlikely(work > weight))
6538 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n",
6539 n->poll, work, weight);
6540
6541 if (likely(work < weight))
6542 return work;
6543
6544 /* Drivers must not modify the NAPI state if they
6545 * consume the entire weight. In such cases this code
6546 * still "owns" the NAPI instance and therefore can
6547 * move the instance around on the list at-will.
6548 */
6549 if (unlikely(napi_disable_pending(n))) {
6550 napi_complete(n);
6551 return work;
6552 }
6553
6554 /* The NAPI context has more processing work, but busy-polling
6555 * is preferred. Exit early.
6556 */
6557 if (napi_prefer_busy_poll(n)) {
6558 if (napi_complete_done(n, work)) {
6559 /* If timeout is not set, we need to make sure
6560 * that the NAPI is re-scheduled.
6561 */
6562 napi_schedule(n);
6563 }
6564 return work;
6565 }
6566
6567 if (n->gro_bitmask) {
6568 /* flush too old packets
6569 * If HZ < 1000, flush all packets.
6570 */
6571 napi_gro_flush(napi: n, HZ >= 1000);
6572 }
6573
6574 gro_normal_list(napi: n);
6575
6576 /* Some drivers may have called napi_schedule
6577 * prior to exhausting their budget.
6578 */
6579 if (unlikely(!list_empty(&n->poll_list))) {
6580 pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
6581 n->dev ? n->dev->name : "backlog");
6582 return work;
6583 }
6584
6585 *repoll = true;
6586
6587 return work;
6588}
6589
6590static int napi_poll(struct napi_struct *n, struct list_head *repoll)
6591{
6592 bool do_repoll = false;
6593 void *have;
6594 int work;
6595
6596 list_del_init(entry: &n->poll_list);
6597
6598 have = netpoll_poll_lock(napi: n);
6599
6600 work = __napi_poll(n, repoll: &do_repoll);
6601
6602 if (do_repoll)
6603 list_add_tail(new: &n->poll_list, head: repoll);
6604
6605 netpoll_poll_unlock(have);
6606
6607 return work;
6608}
6609
6610static int napi_thread_wait(struct napi_struct *napi)
6611{
6612 bool woken = false;
6613
6614 set_current_state(TASK_INTERRUPTIBLE);
6615
6616 while (!kthread_should_stop()) {
6617 /* Testing SCHED_THREADED bit here to make sure the current
6618 * kthread owns this napi and could poll on this napi.
6619 * Testing SCHED bit is not enough because SCHED bit might be
6620 * set by some other busy poll thread or by napi_disable().
6621 */
6622 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state) || woken) {
6623 WARN_ON(!list_empty(&napi->poll_list));
6624 __set_current_state(TASK_RUNNING);
6625 return 0;
6626 }
6627
6628 schedule();
6629 /* woken being true indicates this thread owns this napi. */
6630 woken = true;
6631 set_current_state(TASK_INTERRUPTIBLE);
6632 }
6633 __set_current_state(TASK_RUNNING);
6634
6635 return -1;
6636}
6637
6638static void skb_defer_free_flush(struct softnet_data *sd)
6639{
6640 struct sk_buff *skb, *next;
6641
6642 /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */
6643 if (!READ_ONCE(sd->defer_list))
6644 return;
6645
6646 spin_lock(lock: &sd->defer_lock);
6647 skb = sd->defer_list;
6648 sd->defer_list = NULL;
6649 sd->defer_count = 0;
6650 spin_unlock(lock: &sd->defer_lock);
6651
6652 while (skb != NULL) {
6653 next = skb->next;
6654 napi_consume_skb(skb, budget: 1);
6655 skb = next;
6656 }
6657}
6658
6659static int napi_threaded_poll(void *data)
6660{
6661 struct napi_struct *napi = data;
6662 struct softnet_data *sd;
6663 void *have;
6664
6665 while (!napi_thread_wait(napi)) {
6666 for (;;) {
6667 bool repoll = false;
6668
6669 local_bh_disable();
6670 sd = this_cpu_ptr(&softnet_data);
6671 sd->in_napi_threaded_poll = true;
6672
6673 have = netpoll_poll_lock(napi);
6674 __napi_poll(n: napi, repoll: &repoll);
6675 netpoll_poll_unlock(have);
6676
6677 sd->in_napi_threaded_poll = false;
6678 barrier();
6679
6680 if (sd_has_rps_ipi_waiting(sd)) {
6681 local_irq_disable();
6682 net_rps_action_and_irq_enable(sd);
6683 }
6684 skb_defer_free_flush(sd);
6685 local_bh_enable();
6686
6687 if (!repoll)
6688 break;
6689
6690 cond_resched();
6691 }
6692 }
6693 return 0;
6694}
6695
6696static __latent_entropy void net_rx_action(struct softirq_action *h)
6697{
6698 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
6699 unsigned long time_limit = jiffies +
6700 usecs_to_jiffies(READ_ONCE(netdev_budget_usecs));
6701 int budget = READ_ONCE(netdev_budget);
6702 LIST_HEAD(list);
6703 LIST_HEAD(repoll);
6704
6705start:
6706 sd->in_net_rx_action = true;
6707 local_irq_disable();
6708 list_splice_init(list: &sd->poll_list, head: &list);
6709 local_irq_enable();
6710
6711 for (;;) {
6712 struct napi_struct *n;
6713
6714 skb_defer_free_flush(sd);
6715
6716 if (list_empty(head: &list)) {
6717 if (list_empty(head: &repoll)) {
6718 sd->in_net_rx_action = false;
6719 barrier();
6720 /* We need to check if ____napi_schedule()
6721 * had refilled poll_list while
6722 * sd->in_net_rx_action was true.
6723 */
6724 if (!list_empty(head: &sd->poll_list))
6725 goto start;
6726 if (!sd_has_rps_ipi_waiting(sd))
6727 goto end;
6728 }
6729 break;
6730 }
6731
6732 n = list_first_entry(&list, struct napi_struct, poll_list);
6733 budget -= napi_poll(n, repoll: &repoll);
6734
6735 /* If softirq window is exhausted then punt.
6736 * Allow this to run for 2 jiffies since which will allow
6737 * an average latency of 1.5/HZ.
6738 */
6739 if (unlikely(budget <= 0 ||
6740 time_after_eq(jiffies, time_limit))) {
6741 sd->time_squeeze++;
6742 break;
6743 }
6744 }
6745
6746 local_irq_disable();
6747
6748 list_splice_tail_init(list: &sd->poll_list, head: &list);
6749 list_splice_tail(list: &repoll, head: &list);
6750 list_splice(list: &list, head: &sd->poll_list);
6751 if (!list_empty(head: &sd->poll_list))
6752 __raise_softirq_irqoff(nr: NET_RX_SOFTIRQ);
6753 else
6754 sd->in_net_rx_action = false;
6755
6756 net_rps_action_and_irq_enable(sd);
6757end:;
6758}
6759
6760struct netdev_adjacent {
6761 struct net_device *dev;
6762 netdevice_tracker dev_tracker;
6763
6764 /* upper master flag, there can only be one master device per list */
6765 bool master;
6766
6767 /* lookup ignore flag */
6768 bool ignore;
6769
6770 /* counter for the number of times this device was added to us */
6771 u16 ref_nr;
6772
6773 /* private field for the users */
6774 void *private;
6775
6776 struct list_head list;
6777 struct rcu_head rcu;
6778};
6779
6780static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
6781 struct list_head *adj_list)
6782{
6783 struct netdev_adjacent *adj;
6784
6785 list_for_each_entry(adj, adj_list, list) {
6786 if (adj->dev == adj_dev)
6787 return adj;
6788 }
6789 return NULL;
6790}
6791
6792static int ____netdev_has_upper_dev(struct net_device *upper_dev,
6793 struct netdev_nested_priv *priv)
6794{
6795 struct net_device *dev = (struct net_device *)priv->data;
6796
6797 return upper_dev == dev;
6798}
6799
6800/**
6801 * netdev_has_upper_dev - Check if device is linked to an upper device
6802 * @dev: device
6803 * @upper_dev: upper device to check
6804 *
6805 * Find out if a device is linked to specified upper device and return true
6806 * in case it is. Note that this checks only immediate upper device,
6807 * not through a complete stack of devices. The caller must hold the RTNL lock.
6808 */
6809bool netdev_has_upper_dev(struct net_device *dev,
6810 struct net_device *upper_dev)
6811{
6812 struct netdev_nested_priv priv = {
6813 .data = (void *)upper_dev,
6814 };
6815
6816 ASSERT_RTNL();
6817
6818 return netdev_walk_all_upper_dev_rcu(dev, fn: ____netdev_has_upper_dev,
6819 priv: &priv);
6820}
6821EXPORT_SYMBOL(netdev_has_upper_dev);
6822
6823/**
6824 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device
6825 * @dev: device
6826 * @upper_dev: upper device to check
6827 *
6828 * Find out if a device is linked to specified upper device and return true
6829 * in case it is. Note that this checks the entire upper device chain.
6830 * The caller must hold rcu lock.
6831 */
6832
6833bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
6834 struct net_device *upper_dev)
6835{
6836 struct netdev_nested_priv priv = {
6837 .data = (void *)upper_dev,
6838 };
6839
6840 return !!netdev_walk_all_upper_dev_rcu(dev, fn: ____netdev_has_upper_dev,
6841 priv: &priv);
6842}
6843EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu);
6844
6845/**
6846 * netdev_has_any_upper_dev - Check if device is linked to some device
6847 * @dev: device
6848 *
6849 * Find out if a device is linked to an upper device and return true in case
6850 * it is. The caller must hold the RTNL lock.
6851 */
6852bool netdev_has_any_upper_dev(struct net_device *dev)
6853{
6854 ASSERT_RTNL();
6855
6856 return !list_empty(head: &dev->adj_list.upper);
6857}
6858EXPORT_SYMBOL(netdev_has_any_upper_dev);
6859
6860/**
6861 * netdev_master_upper_dev_get - Get master upper device
6862 * @dev: device
6863 *
6864 * Find a master upper device and return pointer to it or NULL in case
6865 * it's not there. The caller must hold the RTNL lock.
6866 */
6867struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
6868{
6869 struct netdev_adjacent *upper;
6870
6871 ASSERT_RTNL();
6872
6873 if (list_empty(head: &dev->adj_list.upper))
6874 return NULL;
6875
6876 upper = list_first_entry(&dev->adj_list.upper,
6877 struct netdev_adjacent, list);
6878 if (likely(upper->master))
6879 return upper->dev;
6880 return NULL;
6881}
6882EXPORT_SYMBOL(netdev_master_upper_dev_get);
6883
6884static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev)
6885{
6886 struct netdev_adjacent *upper;
6887
6888 ASSERT_RTNL();
6889
6890 if (list_empty(head: &dev->adj_list.upper))
6891 return NULL;
6892
6893 upper = list_first_entry(&dev->adj_list.upper,
6894 struct netdev_adjacent, list);
6895 if (likely(upper->master) && !upper->ignore)
6896 return upper->dev;
6897 return NULL;
6898}
6899
6900/**
6901 * netdev_has_any_lower_dev - Check if device is linked to some device
6902 * @dev: device
6903 *
6904 * Find out if a device is linked to a lower device and return true in case
6905 * it is. The caller must hold the RTNL lock.
6906 */
6907static bool netdev_has_any_lower_dev(struct net_device *dev)
6908{
6909 ASSERT_RTNL();
6910
6911 return !list_empty(head: &dev->adj_list.lower);
6912}
6913
6914void *netdev_adjacent_get_private(struct list_head *adj_list)
6915{
6916 struct netdev_adjacent *adj;
6917
6918 adj = list_entry(adj_list, struct netdev_adjacent, list);
6919
6920 return adj->private;
6921}
6922EXPORT_SYMBOL(netdev_adjacent_get_private);
6923
6924/**
6925 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
6926 * @dev: device
6927 * @iter: list_head ** of the current position
6928 *
6929 * Gets the next device from the dev's upper list, starting from iter
6930 * position. The caller must hold RCU read lock.
6931 */
6932struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
6933 struct list_head **iter)
6934{
6935 struct netdev_adjacent *upper;
6936
6937 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
6938
6939 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
6940
6941 if (&upper->list == &dev->adj_list.upper)
6942 return NULL;
6943
6944 *iter = &upper->list;
6945
6946 return upper->dev;
6947}
6948EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
6949
6950static struct net_device *__netdev_next_upper_dev(struct net_device *dev,
6951 struct list_head **iter,
6952 bool *ignore)
6953{
6954 struct netdev_adjacent *upper;
6955
6956 upper = list_entry((*iter)->next, struct netdev_adjacent, list);
6957
6958 if (&upper->list == &dev->adj_list.upper)
6959 return NULL;
6960
6961 *iter = &upper->list;
6962 *ignore = upper->ignore;
6963
6964 return upper->dev;
6965}
6966
6967static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev,
6968 struct list_head **iter)
6969{
6970 struct netdev_adjacent *upper;
6971
6972 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
6973
6974 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
6975
6976 if (&upper->list == &dev->adj_list.upper)
6977 return NULL;
6978
6979 *iter = &upper->list;
6980
6981 return upper->dev;
6982}
6983
6984static int __netdev_walk_all_upper_dev(struct net_device *dev,
6985 int (*fn)(struct net_device *dev,
6986 struct netdev_nested_priv *priv),
6987 struct netdev_nested_priv *priv)
6988{
6989 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
6990 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
6991 int ret, cur = 0;
6992 bool ignore;
6993
6994 now = dev;
6995 iter = &dev->adj_list.upper;
6996
6997 while (1) {
6998 if (now != dev) {
6999 ret = fn(now, priv);
7000 if (ret)
7001 return ret;
7002 }
7003
7004 next = NULL;
7005 while (1) {
7006 udev = __netdev_next_upper_dev(dev: now, iter: &iter, ignore: &ignore);
7007 if (!udev)
7008 break;
7009 if (ignore)
7010 continue;
7011
7012 next = udev;
7013 niter = &udev->adj_list.upper;
7014 dev_stack[cur] = now;
7015 iter_stack[cur++] = iter;
7016 break;
7017 }
7018
7019 if (!next) {
7020 if (!cur)
7021 return 0;
7022 next = dev_stack[--cur];
7023 niter = iter_stack[cur];
7024 }
7025
7026 now = next;
7027 iter = niter;
7028 }
7029
7030 return 0;
7031}
7032
7033int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
7034 int (*fn)(struct net_device *dev,
7035 struct netdev_nested_priv *priv),
7036 struct netdev_nested_priv *priv)
7037{
7038 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
7039 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
7040 int ret, cur = 0;
7041
7042 now = dev;
7043 iter = &dev->adj_list.upper;
7044
7045 while (1) {
7046 if (now != dev) {
7047 ret = fn(now, priv);
7048 if (ret)
7049 return ret;
7050 }
7051
7052 next = NULL;
7053 while (1) {
7054 udev = netdev_next_upper_dev_rcu(dev: now, iter: &iter);
7055 if (!udev)
7056 break;
7057
7058 next = udev;
7059 niter = &udev->adj_list.upper;
7060 dev_stack[cur] = now;
7061 iter_stack[cur++] = iter;
7062 break;
7063 }
7064
7065 if (!next) {
7066 if (!cur)
7067 return 0;
7068 next = dev_stack[--cur];
7069 niter = iter_stack[cur];
7070 }
7071
7072 now = next;
7073 iter = niter;
7074 }
7075
7076 return 0;
7077}
7078EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu);
7079
7080static bool __netdev_has_upper_dev(struct net_device *dev,
7081 struct net_device *upper_dev)
7082{
7083 struct netdev_nested_priv priv = {
7084 .flags = 0,
7085 .data = (void *)upper_dev,
7086 };
7087
7088 ASSERT_RTNL();
7089
7090 return __netdev_walk_all_upper_dev(dev, fn: ____netdev_has_upper_dev,
7091 priv: &priv);
7092}
7093
7094/**
7095 * netdev_lower_get_next_private - Get the next ->private from the
7096 * lower neighbour list
7097 * @dev: device
7098 * @iter: list_head ** of the current position
7099 *
7100 * Gets the next netdev_adjacent->private from the dev's lower neighbour
7101 * list, starting from iter position. The caller must hold either hold the
7102 * RTNL lock or its own locking that guarantees that the neighbour lower
7103 * list will remain unchanged.
7104 */
7105void *netdev_lower_get_next_private(struct net_device *dev,
7106 struct list_head **iter)
7107{
7108 struct netdev_adjacent *lower;
7109
7110 lower = list_entry(*iter, struct netdev_adjacent, list);
7111
7112 if (&lower->list == &dev->adj_list.lower)
7113 return NULL;
7114
7115 *iter = lower->list.next;
7116
7117 return lower->private;
7118}
7119EXPORT_SYMBOL(netdev_lower_get_next_private);
7120
7121/**
7122 * netdev_lower_get_next_private_rcu - Get the next ->private from the
7123 * lower neighbour list, RCU
7124 * variant
7125 * @dev: device
7126 * @iter: list_head ** of the current position
7127 *
7128 * Gets the next netdev_adjacent->private from the dev's lower neighbour
7129 * list, starting from iter position. The caller must hold RCU read lock.
7130 */
7131void *netdev_lower_get_next_private_rcu(struct net_device *dev,
7132 struct list_head **iter)
7133{
7134 struct netdev_adjacent *lower;
7135
7136 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
7137
7138 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
7139
7140 if (&lower->list == &dev->adj_list.lower)
7141 return NULL;
7142
7143 *iter = &lower->list;
7144
7145 return lower->private;
7146}
7147EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
7148
7149/**
7150 * netdev_lower_get_next - Get the next device from the lower neighbour
7151 * list
7152 * @dev: device
7153 * @iter: list_head ** of the current position
7154 *
7155 * Gets the next netdev_adjacent from the dev's lower neighbour
7156 * list, starting from iter position. The caller must hold RTNL lock or
7157 * its own locking that guarantees that the neighbour lower
7158 * list will remain unchanged.
7159 */
7160void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
7161{
7162 struct netdev_adjacent *lower;
7163
7164 lower = list_entry(*iter, struct netdev_adjacent, list);
7165
7166 if (&lower->list == &dev->adj_list.lower)
7167 return NULL;
7168
7169 *iter = lower->list.next;
7170
7171 return lower->dev;
7172}
7173EXPORT_SYMBOL(netdev_lower_get_next);
7174
7175static struct net_device *netdev_next_lower_dev(struct net_device *dev,
7176 struct list_head **iter)
7177{
7178 struct netdev_adjacent *lower;
7179
7180 lower = list_entry((*iter)->next, struct netdev_adjacent, list);
7181
7182 if (&lower->list == &dev->adj_list.lower)
7183 return NULL;
7184
7185 *iter = &lower->list;
7186
7187 return lower->dev;
7188}
7189
7190static struct net_device *__netdev_next_lower_dev(struct net_device *dev,
7191 struct list_head **iter,
7192 bool *ignore)
7193{
7194 struct netdev_adjacent *lower;
7195
7196 lower = list_entry((*iter)->next, struct netdev_adjacent, list);
7197
7198 if (&lower->list == &dev->adj_list.lower)
7199 return NULL;
7200
7201 *iter = &lower->list;
7202 *ignore = lower->ignore;
7203
7204 return lower->dev;
7205}
7206
7207int netdev_walk_all_lower_dev(struct net_device *dev,
7208 int (*fn)(struct net_device *dev,
7209 struct netdev_nested_priv *priv),
7210 struct netdev_nested_priv *priv)
7211{
7212 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
7213 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
7214 int ret, cur = 0;
7215
7216 now = dev;
7217 iter = &dev->adj_list.lower;
7218
7219 while (1) {
7220 if (now != dev) {
7221 ret = fn(now, priv);
7222 if (ret)
7223 return ret;
7224 }
7225
7226 next = NULL;
7227 while (1) {
7228 ldev = netdev_next_lower_dev(dev: now, iter: &iter);
7229 if (!ldev)
7230 break;
7231
7232 next = ldev;
7233 niter = &ldev->adj_list.lower;
7234 dev_stack[cur] = now;
7235 iter_stack[cur++] = iter;
7236 break;
7237 }
7238
7239 if (!next) {
7240 if (!cur)
7241 return 0;
7242 next = dev_stack[--cur];
7243 niter = iter_stack[cur];
7244 }
7245
7246 now = next;
7247 iter = niter;
7248 }
7249
7250 return 0;
7251}
7252EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);
7253
7254static int __netdev_walk_all_lower_dev(struct net_device *dev,
7255 int (*fn)(struct net_device *dev,
7256 struct netdev_nested_priv *priv),
7257 struct netdev_nested_priv *priv)
7258{
7259 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
7260 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
7261 int ret, cur = 0;
7262 bool ignore;
7263
7264 now = dev;
7265 iter = &dev->adj_list.lower;
7266
7267 while (1) {
7268 if (now != dev) {
7269 ret = fn(now, priv);
7270 if (ret)
7271 return ret;
7272 }
7273
7274 next = NULL;
7275 while (1) {
7276 ldev = __netdev_next_lower_dev(dev: now, iter: &iter, ignore: &ignore);
7277 if (!ldev)
7278 break;
7279 if (ignore)
7280 continue;
7281
7282 next = ldev;
7283 niter = &ldev->adj_list.lower;
7284 dev_stack[cur] = now;
7285 iter_stack[cur++] = iter;
7286 break;
7287 }
7288
7289 if (!next) {
7290 if (!cur)
7291 return 0;
7292 next = dev_stack[--cur];
7293 niter = iter_stack[cur];
7294 }
7295
7296 now = next;
7297 iter = niter;
7298 }
7299
7300 return 0;
7301}
7302
7303struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
7304 struct list_head **iter)
7305{
7306 struct netdev_adjacent *lower;
7307
7308 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
7309 if (&lower->list == &dev->adj_list.lower)
7310 return NULL;
7311
7312 *iter = &lower->list;
7313
7314 return lower->dev;
7315}
7316EXPORT_SYMBOL(netdev_next_lower_dev_rcu);
7317
7318static u8 __netdev_upper_depth(struct net_device *dev)
7319{
7320 struct net_device *udev;
7321 struct list_head *iter;
7322 u8 max_depth = 0;
7323 bool ignore;
7324
7325 for (iter = &dev->adj_list.upper,
7326 udev = __netdev_next_upper_dev(dev, iter: &iter, ignore: &ignore);
7327 udev;
7328 udev = __netdev_next_upper_dev(dev, iter: &iter, ignore: &ignore)) {
7329 if (ignore)
7330 continue;
7331 if (max_depth < udev->upper_level)
7332 max_depth = udev->upper_level;
7333 }
7334
7335 return max_depth;
7336}
7337
7338static u8 __netdev_lower_depth(struct net_device *dev)
7339{
7340 struct net_device *ldev;
7341 struct list_head *iter;
7342 u8 max_depth = 0;
7343 bool ignore;
7344
7345 for (iter = &dev->adj_list.lower,
7346 ldev = __netdev_next_lower_dev(dev, iter: &iter, ignore: &ignore);
7347 ldev;
7348 ldev = __netdev_next_lower_dev(dev, iter: &iter, ignore: &ignore)) {
7349 if (ignore)
7350 continue;
7351 if (max_depth < ldev->lower_level)
7352 max_depth = ldev->lower_level;
7353 }
7354
7355 return max_depth;
7356}
7357
7358static int __netdev_update_upper_level(struct net_device *dev,
7359 struct netdev_nested_priv *__unused)
7360{
7361 dev->upper_level = __netdev_upper_depth(dev) + 1;
7362 return 0;
7363}
7364
7365#ifdef CONFIG_LOCKDEP
7366static LIST_HEAD(net_unlink_list);
7367
7368static void net_unlink_todo(struct net_device *dev)
7369{
7370 if (list_empty(head: &dev->unlink_list))
7371 list_add_tail(new: &dev->unlink_list, head: &net_unlink_list);
7372}
7373#endif
7374
7375static int __netdev_update_lower_level(struct net_device *dev,
7376 struct netdev_nested_priv *priv)
7377{
7378 dev->lower_level = __netdev_lower_depth(dev) + 1;
7379
7380#ifdef CONFIG_LOCKDEP
7381 if (!priv)
7382 return 0;
7383
7384 if (priv->flags & NESTED_SYNC_IMM)
7385 dev->nested_level = dev->lower_level - 1;
7386 if (priv->flags & NESTED_SYNC_TODO)
7387 net_unlink_todo(dev);
7388#endif
7389 return 0;
7390}
7391
7392int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
7393 int (*fn)(struct net_device *dev,
7394 struct netdev_nested_priv *priv),
7395 struct netdev_nested_priv *priv)
7396{
7397 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
7398 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
7399 int ret, cur = 0;
7400
7401 now = dev;
7402 iter = &dev->adj_list.lower;
7403
7404 while (1) {
7405 if (now != dev) {
7406 ret = fn(now, priv);
7407 if (ret)
7408 return ret;
7409 }
7410
7411 next = NULL;
7412 while (1) {
7413 ldev = netdev_next_lower_dev_rcu(now, &iter);
7414 if (!ldev)
7415 break;
7416
7417 next = ldev;
7418 niter = &ldev->adj_list.lower;
7419 dev_stack[cur] = now;
7420 iter_stack[cur++] = iter;
7421 break;
7422 }
7423
7424 if (!next) {
7425 if (!cur)
7426 return 0;
7427 next = dev_stack[--cur];
7428 niter = iter_stack[cur];
7429 }
7430
7431 now = next;
7432 iter = niter;
7433 }
7434
7435 return 0;
7436}
7437EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu);
7438
7439/**
7440 * netdev_lower_get_first_private_rcu - Get the first ->private from the
7441 * lower neighbour list, RCU
7442 * variant
7443 * @dev: device
7444 *
7445 * Gets the first netdev_adjacent->private from the dev's lower neighbour
7446 * list. The caller must hold RCU read lock.
7447 */
7448void *netdev_lower_get_first_private_rcu(struct net_device *dev)
7449{
7450 struct netdev_adjacent *lower;
7451
7452 lower = list_first_or_null_rcu(&dev->adj_list.lower,
7453 struct netdev_adjacent, list);
7454 if (lower)
7455 return lower->private;
7456 return NULL;
7457}
7458EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
7459
7460/**
7461 * netdev_master_upper_dev_get_rcu - Get master upper device
7462 * @dev: device
7463 *
7464 * Find a master upper device and return pointer to it or NULL in case
7465 * it's not there. The caller must hold the RCU read lock.
7466 */
7467struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
7468{
7469 struct netdev_adjacent *upper;
7470
7471 upper = list_first_or_null_rcu(&dev->adj_list.upper,
7472 struct netdev_adjacent, list);
7473 if (upper && likely(upper->master))
7474 return upper->dev;
7475 return NULL;
7476}
7477EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
7478
7479static int netdev_adjacent_sysfs_add(struct net_device *dev,
7480 struct net_device *adj_dev,
7481 struct list_head *dev_list)
7482{
7483 char linkname[IFNAMSIZ+7];
7484
7485 sprintf(buf: linkname, fmt: dev_list == &dev->adj_list.upper ?
7486 "upper_%s" : "lower_%s", adj_dev->name);
7487 return sysfs_create_link(kobj: &(dev->dev.kobj), target: &(adj_dev->dev.kobj),
7488 name: linkname);
7489}
7490static void netdev_adjacent_sysfs_del(struct net_device *dev,
7491 char *name,
7492 struct list_head *dev_list)
7493{
7494 char linkname[IFNAMSIZ+7];
7495
7496 sprintf(buf: linkname, fmt: dev_list == &dev->adj_list.upper ?
7497 "upper_%s" : "lower_%s", name);
7498 sysfs_remove_link(kobj: &(dev->dev.kobj), name: linkname);
7499}
7500
7501static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
7502 struct net_device *adj_dev,
7503 struct list_head *dev_list)
7504{
7505 return (dev_list == &dev->adj_list.upper ||
7506 dev_list == &dev->adj_list.lower) &&
7507 net_eq(net1: dev_net(dev), net2: dev_net(dev: adj_dev));
7508}
7509
7510static int __netdev_adjacent_dev_insert(struct net_device *dev,
7511 struct net_device *adj_dev,
7512 struct list_head *dev_list,
7513 void *private, bool master)
7514{
7515 struct netdev_adjacent *adj;
7516 int ret;
7517
7518 adj = __netdev_find_adj(adj_dev, adj_list: dev_list);
7519
7520 if (adj) {
7521 adj->ref_nr += 1;
7522 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
7523 dev->name, adj_dev->name, adj->ref_nr);
7524
7525 return 0;
7526 }
7527
7528 adj = kmalloc(size: sizeof(*adj), GFP_KERNEL);
7529 if (!adj)
7530 return -ENOMEM;
7531
7532 adj->dev = adj_dev;
7533 adj->master = master;
7534 adj->ref_nr = 1;
7535 adj->private = private;
7536 adj->ignore = false;
7537 netdev_hold(dev: adj_dev, tracker: &adj->dev_tracker, GFP_KERNEL);
7538
7539 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
7540 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
7541
7542 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
7543 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
7544 if (ret)
7545 goto free_adj;
7546 }
7547
7548 /* Ensure that master link is always the first item in list. */
7549 if (master) {
7550 ret = sysfs_create_link(kobj: &(dev->dev.kobj),
7551 target: &(adj_dev->dev.kobj), name: "master");
7552 if (ret)
7553 goto remove_symlinks;
7554
7555 list_add_rcu(new: &adj->list, head: dev_list);
7556 } else {
7557 list_add_tail_rcu(new: &adj->list, head: dev_list);
7558 }
7559
7560 return 0;
7561
7562remove_symlinks:
7563 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
7564 netdev_adjacent_sysfs_del(dev, name: adj_dev->name, dev_list);
7565free_adj:
7566 netdev_put(dev: adj_dev, tracker: &adj->dev_tracker);
7567 kfree(objp: adj);
7568
7569 return ret;
7570}
7571
7572static void __netdev_adjacent_dev_remove(struct net_device *dev,
7573 struct net_device *adj_dev,
7574 u16 ref_nr,
7575 struct list_head *dev_list)
7576{
7577 struct netdev_adjacent *adj;
7578
7579 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
7580 dev->name, adj_dev->name, ref_nr);
7581
7582 adj = __netdev_find_adj(adj_dev, adj_list: dev_list);
7583
7584 if (!adj) {
7585 pr_err("Adjacency does not exist for device %s from %s\n",
7586 dev->name, adj_dev->name);
7587 WARN_ON(1);
7588 return;
7589 }
7590
7591 if (adj->ref_nr > ref_nr) {
7592 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
7593 dev->name, adj_dev->name, ref_nr,
7594 adj->ref_nr - ref_nr);
7595 adj->ref_nr -= ref_nr;
7596 return;
7597 }
7598
7599 if (adj->master)
7600 sysfs_remove_link(kobj: &(dev->dev.kobj), name: "master");
7601
7602 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
7603 netdev_adjacent_sysfs_del(dev, name: adj_dev->name, dev_list);
7604
7605 list_del_rcu(entry: &adj->list);
7606 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
7607 adj_dev->name, dev->name, adj_dev->name);
7608 netdev_put(dev: adj_dev, tracker: &adj->dev_tracker);
7609 kfree_rcu(adj, rcu);
7610}
7611
7612static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
7613 struct net_device *upper_dev,
7614 struct list_head *up_list,
7615 struct list_head *down_list,
7616 void *private, bool master)
7617{
7618 int ret;
7619
7620 ret = __netdev_adjacent_dev_insert(dev, adj_dev: upper_dev, dev_list: up_list,
7621 private, master);
7622 if (ret)
7623 return ret;
7624
7625 ret = __netdev_adjacent_dev_insert(dev: upper_dev, adj_dev: dev, dev_list: down_list,
7626 private, master: false);
7627 if (ret) {
7628 __netdev_adjacent_dev_remove(dev, adj_dev: upper_dev, ref_nr: 1, dev_list: up_list);
7629 return ret;
7630 }
7631
7632 return 0;
7633}
7634
7635static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
7636 struct net_device *upper_dev,
7637 u16 ref_nr,
7638 struct list_head *up_list,
7639 struct list_head *down_list)
7640{
7641 __netdev_adjacent_dev_remove(dev, adj_dev: upper_dev, ref_nr, dev_list: up_list);
7642 __netdev_adjacent_dev_remove(dev: upper_dev, adj_dev: dev, ref_nr, dev_list: down_list);
7643}
7644
7645static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
7646 struct net_device *upper_dev,
7647 void *private, bool master)
7648{
7649 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
7650 up_list: &dev->adj_list.upper,
7651 down_list: &upper_dev->adj_list.lower,
7652 private, master);
7653}
7654
7655static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
7656 struct net_device *upper_dev)
7657{
7658 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, ref_nr: 1,
7659 up_list: &dev->adj_list.upper,
7660 down_list: &upper_dev->adj_list.lower);
7661}
7662
7663static int __netdev_upper_dev_link(struct net_device *dev,
7664 struct net_device *upper_dev, bool master,
7665 void *upper_priv, void *upper_info,
7666 struct netdev_nested_priv *priv,
7667 struct netlink_ext_ack *extack)
7668{
7669 struct netdev_notifier_changeupper_info changeupper_info = {
7670 .info = {
7671 .dev = dev,
7672 .extack = extack,
7673 },
7674 .upper_dev = upper_dev,
7675 .master = master,
7676 .linking = true,
7677 .upper_info = upper_info,
7678 };
7679 struct net_device *master_dev;
7680 int ret = 0;
7681
7682 ASSERT_RTNL();
7683
7684 if (dev == upper_dev)
7685 return -EBUSY;
7686
7687 /* To prevent loops, check if dev is not upper device to upper_dev. */
7688 if (__netdev_has_upper_dev(dev: upper_dev, upper_dev: dev))
7689 return -EBUSY;
7690
7691 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV)
7692 return -EMLINK;
7693
7694 if (!master) {
7695 if (__netdev_has_upper_dev(dev, upper_dev))
7696 return -EEXIST;
7697 } else {
7698 master_dev = __netdev_master_upper_dev_get(dev);
7699 if (master_dev)
7700 return master_dev == upper_dev ? -EEXIST : -EBUSY;
7701 }
7702
7703 ret = call_netdevice_notifiers_info(val: NETDEV_PRECHANGEUPPER,
7704 info: &changeupper_info.info);
7705 ret = notifier_to_errno(ret);
7706 if (ret)
7707 return ret;
7708
7709 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private: upper_priv,
7710 master);
7711 if (ret)
7712 return ret;
7713
7714 ret = call_netdevice_notifiers_info(val: NETDEV_CHANGEUPPER,
7715 info: &changeupper_info.info);
7716 ret = notifier_to_errno(ret);
7717 if (ret)
7718 goto rollback;
7719
7720 __netdev_update_upper_level(dev, NULL);
7721 __netdev_walk_all_lower_dev(dev, fn: __netdev_update_upper_level, NULL);
7722
7723 __netdev_update_lower_level(dev: upper_dev, priv);
7724 __netdev_walk_all_upper_dev(dev: upper_dev, fn: __netdev_update_lower_level,
7725 priv);
7726
7727 return 0;
7728
7729rollback:
7730 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
7731
7732 return ret;
7733}
7734
7735/**
7736 * netdev_upper_dev_link - Add a link to the upper device
7737 * @dev: device
7738 * @upper_dev: new upper device
7739 * @extack: netlink extended ack
7740 *
7741 * Adds a link to device which is upper to this one. The caller must hold
7742 * the RTNL lock. On a failure a negative errno code is returned.
7743 * On success the reference counts are adjusted and the function
7744 * returns zero.
7745 */
7746int netdev_upper_dev_link(struct net_device *dev,
7747 struct net_device *upper_dev,
7748 struct netlink_ext_ack *extack)
7749{
7750 struct netdev_nested_priv priv = {
7751 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
7752 .data = NULL,
7753 };
7754
7755 return __netdev_upper_dev_link(dev, upper_dev, master: false,
7756 NULL, NULL, priv: &priv, extack);
7757}
7758EXPORT_SYMBOL(netdev_upper_dev_link);
7759
7760/**
7761 * netdev_master_upper_dev_link - Add a master link to the upper device
7762 * @dev: device
7763 * @upper_dev: new upper device
7764 * @upper_priv: upper device private
7765 * @upper_info: upper info to be passed down via notifier
7766 * @extack: netlink extended ack
7767 *
7768 * Adds a link to device which is upper to this one. In this case, only
7769 * one master upper device can be linked, although other non-master devices
7770 * might be linked as well. The caller must hold the RTNL lock.
7771 * On a failure a negative errno code is returned. On success the reference
7772 * counts are adjusted and the function returns zero.
7773 */
7774int netdev_master_upper_dev_link(struct net_device *dev,
7775 struct net_device *upper_dev,
7776 void *upper_priv, void *upper_info,
7777 struct netlink_ext_ack *extack)
7778{
7779 struct netdev_nested_priv priv = {
7780 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
7781 .data = NULL,
7782 };
7783
7784 return __netdev_upper_dev_link(dev, upper_dev, master: true,
7785 upper_priv, upper_info, priv: &priv, extack);
7786}
7787EXPORT_SYMBOL(netdev_master_upper_dev_link);
7788
7789static void __netdev_upper_dev_unlink(struct net_device *dev,
7790 struct net_device *upper_dev,
7791 struct netdev_nested_priv *priv)
7792{
7793 struct netdev_notifier_changeupper_info changeupper_info = {
7794 .info = {
7795 .dev = dev,
7796 },
7797 .upper_dev = upper_dev,
7798 .linking = false,
7799 };
7800
7801 ASSERT_RTNL();
7802
7803 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
7804
7805 call_netdevice_notifiers_info(val: NETDEV_PRECHANGEUPPER,
7806 info: &changeupper_info.info);
7807
7808 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
7809
7810 call_netdevice_notifiers_info(val: NETDEV_CHANGEUPPER,
7811 info: &changeupper_info.info);
7812
7813 __netdev_update_upper_level(dev, NULL);
7814 __netdev_walk_all_lower_dev(dev, fn: __netdev_update_upper_level, NULL);
7815
7816 __netdev_update_lower_level(dev: upper_dev, priv);
7817 __netdev_walk_all_upper_dev(dev: upper_dev, fn: __netdev_update_lower_level,
7818 priv);
7819}
7820
7821/**
7822 * netdev_upper_dev_unlink - Removes a link to upper device
7823 * @dev: device
7824 * @upper_dev: new upper device
7825 *
7826 * Removes a link to device which is upper to this one. The caller must hold
7827 * the RTNL lock.
7828 */
7829void netdev_upper_dev_unlink(struct net_device *dev,
7830 struct net_device *upper_dev)
7831{
7832 struct netdev_nested_priv priv = {
7833 .flags = NESTED_SYNC_TODO,
7834 .data = NULL,
7835 };
7836
7837 __netdev_upper_dev_unlink(dev, upper_dev, priv: &priv);
7838}
7839EXPORT_SYMBOL(netdev_upper_dev_unlink);
7840
7841static void __netdev_adjacent_dev_set(struct net_device *upper_dev,
7842 struct net_device *lower_dev,
7843 bool val)
7844{
7845 struct netdev_adjacent *adj;
7846
7847 adj = __netdev_find_adj(adj_dev: lower_dev, adj_list: &upper_dev->adj_list.lower);
7848 if (adj)
7849 adj->ignore = val;
7850
7851 adj = __netdev_find_adj(adj_dev: upper_dev, adj_list: &lower_dev->adj_list.upper);
7852 if (adj)
7853 adj->ignore = val;
7854}
7855
7856static void netdev_adjacent_dev_disable(struct net_device *upper_dev,
7857 struct net_device *lower_dev)
7858{
7859 __netdev_adjacent_dev_set(upper_dev, lower_dev, val: true);
7860}
7861
7862static void netdev_adjacent_dev_enable(struct net_device *upper_dev,
7863 struct net_device *lower_dev)
7864{
7865 __netdev_adjacent_dev_set(upper_dev, lower_dev, val: false);
7866}
7867
7868int netdev_adjacent_change_prepare(struct net_device *old_dev,
7869 struct net_device *new_dev,
7870 struct net_device *dev,
7871 struct netlink_ext_ack *extack)
7872{
7873 struct netdev_nested_priv priv = {
7874 .flags = 0,
7875 .data = NULL,
7876 };
7877 int err;
7878
7879 if (!new_dev)
7880 return 0;
7881
7882 if (old_dev && new_dev != old_dev)
7883 netdev_adjacent_dev_disable(upper_dev: dev, lower_dev: old_dev);
7884 err = __netdev_upper_dev_link(dev: new_dev, upper_dev: dev, master: false, NULL, NULL, priv: &priv,
7885 extack);
7886 if (err) {
7887 if (old_dev && new_dev != old_dev)
7888 netdev_adjacent_dev_enable(upper_dev: dev, lower_dev: old_dev);
7889 return err;
7890 }
7891
7892 return 0;
7893}
7894EXPORT_SYMBOL(netdev_adjacent_change_prepare);
7895
7896void netdev_adjacent_change_commit(struct net_device *old_dev,
7897 struct net_device *new_dev,
7898 struct net_device *dev)
7899{
7900 struct netdev_nested_priv priv = {
7901 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
7902 .data = NULL,
7903 };
7904
7905 if (!new_dev || !old_dev)
7906 return;
7907
7908 if (new_dev == old_dev)
7909 return;
7910
7911 netdev_adjacent_dev_enable(upper_dev: dev, lower_dev: old_dev);
7912 __netdev_upper_dev_unlink(dev: old_dev, upper_dev: dev, priv: &priv);
7913}
7914EXPORT_SYMBOL(netdev_adjacent_change_commit);
7915
7916void netdev_adjacent_change_abort(struct net_device *old_dev,
7917 struct net_device *new_dev,
7918 struct net_device *dev)
7919{
7920 struct netdev_nested_priv priv = {
7921 .flags = 0,
7922 .data = NULL,
7923 };
7924
7925 if (!new_dev)
7926 return;
7927
7928 if (old_dev && new_dev != old_dev)
7929 netdev_adjacent_dev_enable(upper_dev: dev, lower_dev: old_dev);
7930
7931 __netdev_upper_dev_unlink(dev: new_dev, upper_dev: dev, priv: &priv);
7932}
7933EXPORT_SYMBOL(netdev_adjacent_change_abort);
7934
7935/**
7936 * netdev_bonding_info_change - Dispatch event about slave change
7937 * @dev: device
7938 * @bonding_info: info to dispatch
7939 *
7940 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
7941 * The caller must hold the RTNL lock.
7942 */
7943void netdev_bonding_info_change(struct net_device *dev,
7944 struct netdev_bonding_info *bonding_info)
7945{
7946 struct netdev_notifier_bonding_info info = {
7947 .info.dev = dev,
7948 };
7949
7950 memcpy(&info.bonding_info, bonding_info,
7951 sizeof(struct netdev_bonding_info));
7952 call_netdevice_notifiers_info(val: NETDEV_BONDING_INFO,
7953 info: &info.info);
7954}
7955EXPORT_SYMBOL(netdev_bonding_info_change);
7956
7957static int netdev_offload_xstats_enable_l3(struct net_device *dev,
7958 struct netlink_ext_ack *extack)
7959{
7960 struct netdev_notifier_offload_xstats_info info = {
7961 .info.dev = dev,
7962 .info.extack = extack,
7963 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3,
7964 };
7965 int err;
7966 int rc;
7967
7968 dev->offload_xstats_l3 = kzalloc(size: sizeof(*dev->offload_xstats_l3),
7969 GFP_KERNEL);
7970 if (!dev->offload_xstats_l3)
7971 return -ENOMEM;
7972
7973 rc = call_netdevice_notifiers_info_robust(val_up: NETDEV_OFFLOAD_XSTATS_ENABLE,
7974 val_down: NETDEV_OFFLOAD_XSTATS_DISABLE,
7975 info: &info.info);
7976 err = notifier_to_errno(ret: rc);
7977 if (err)
7978 goto free_stats;
7979
7980 return 0;
7981
7982free_stats:
7983 kfree(objp: dev->offload_xstats_l3);
7984 dev->offload_xstats_l3 = NULL;
7985 return err;
7986}
7987
7988int netdev_offload_xstats_enable(struct net_device *dev,
7989 enum netdev_offload_xstats_type type,
7990 struct netlink_ext_ack *extack)
7991{
7992 ASSERT_RTNL();
7993
7994 if (netdev_offload_xstats_enabled(dev, type))
7995 return -EALREADY;
7996
7997 switch (type) {
7998 case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
7999 return netdev_offload_xstats_enable_l3(dev, extack);
8000 }
8001
8002 WARN_ON(1);
8003 return -EINVAL;
8004}
8005EXPORT_SYMBOL(netdev_offload_xstats_enable);
8006
8007static void netdev_offload_xstats_disable_l3(struct net_device *dev)
8008{
8009 struct netdev_notifier_offload_xstats_info info = {
8010 .info.dev = dev,
8011 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3,
8012 };
8013
8014 call_netdevice_notifiers_info(val: NETDEV_OFFLOAD_XSTATS_DISABLE,
8015 info: &info.info);
8016 kfree(objp: dev->offload_xstats_l3);
8017 dev->offload_xstats_l3 = NULL;
8018}
8019
8020int netdev_offload_xstats_disable(struct net_device *dev,
8021 enum netdev_offload_xstats_type type)
8022{
8023 ASSERT_RTNL();
8024
8025 if (!netdev_offload_xstats_enabled(dev, type))
8026 return -EALREADY;
8027
8028 switch (type) {
8029 case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
8030 netdev_offload_xstats_disable_l3(dev);
8031 return 0;
8032 }
8033
8034 WARN_ON(1);
8035 return -EINVAL;
8036}
8037EXPORT_SYMBOL(netdev_offload_xstats_disable);
8038
8039static void netdev_offload_xstats_disable_all(struct net_device *dev)
8040{
8041 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3);
8042}
8043
8044static struct rtnl_hw_stats64 *
8045netdev_offload_xstats_get_ptr(const struct net_device *dev,
8046 enum netdev_offload_xstats_type type)
8047{
8048 switch (type) {
8049 case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
8050 return dev->offload_xstats_l3;
8051 }
8052
8053 WARN_ON(1);
8054 return NULL;
8055}
8056
8057bool netdev_offload_xstats_enabled(const struct net_device *dev,
8058 enum netdev_offload_xstats_type type)
8059{
8060 ASSERT_RTNL();
8061
8062 return netdev_offload_xstats_get_ptr(dev, type);
8063}
8064EXPORT_SYMBOL(netdev_offload_xstats_enabled);
8065
8066struct netdev_notifier_offload_xstats_ru {
8067 bool used;
8068};
8069
8070struct netdev_notifier_offload_xstats_rd {
8071 struct rtnl_hw_stats64 stats;
8072 bool used;
8073};
8074
8075static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest,
8076 const struct rtnl_hw_stats64 *src)
8077{
8078 dest->rx_packets += src->rx_packets;
8079 dest->tx_packets += src->tx_packets;
8080 dest->rx_bytes += src->rx_bytes;
8081 dest->tx_bytes += src->tx_bytes;
8082 dest->rx_errors += src->rx_errors;
8083 dest->tx_errors += src->tx_errors;
8084 dest->rx_dropped += src->rx_dropped;
8085 dest->tx_dropped += src->tx_dropped;
8086 dest->multicast += src->multicast;
8087}
8088
8089static int netdev_offload_xstats_get_used(struct net_device *dev,
8090 enum netdev_offload_xstats_type type,
8091 bool *p_used,
8092 struct netlink_ext_ack *extack)
8093{
8094 struct netdev_notifier_offload_xstats_ru report_used = {};
8095 struct netdev_notifier_offload_xstats_info info = {
8096 .info.dev = dev,
8097 .info.extack = extack,
8098 .type = type,
8099 .report_used = &report_used,
8100 };
8101 int rc;
8102
8103 WARN_ON(!netdev_offload_xstats_enabled(dev, type));
8104 rc = call_netdevice_notifiers_info(val: NETDEV_OFFLOAD_XSTATS_REPORT_USED,
8105 info: &info.info);
8106 *p_used = report_used.used;
8107 return notifier_to_errno(ret: rc);
8108}
8109
8110static int netdev_offload_xstats_get_stats(struct net_device *dev,
8111 enum netdev_offload_xstats_type type,
8112 struct rtnl_hw_stats64 *p_stats,
8113 bool *p_used,
8114 struct netlink_ext_ack *extack)
8115{
8116 struct netdev_notifier_offload_xstats_rd report_delta = {};
8117 struct netdev_notifier_offload_xstats_info info = {
8118 .info.dev = dev,
8119 .info.extack = extack,
8120 .type = type,
8121 .report_delta = &report_delta,
8122 };
8123 struct rtnl_hw_stats64 *stats;
8124 int rc;
8125
8126 stats = netdev_offload_xstats_get_ptr(dev, type);
8127 if (WARN_ON(!stats))
8128 return -EINVAL;
8129
8130 rc = call_netdevice_notifiers_info(val: NETDEV_OFFLOAD_XSTATS_REPORT_DELTA,
8131 info: &info.info);
8132
8133 /* Cache whatever we got, even if there was an error, otherwise the
8134 * successful stats retrievals would get lost.
8135 */
8136 netdev_hw_stats64_add(dest: stats, src: &report_delta.stats);
8137
8138 if (p_stats)
8139 *p_stats = *stats;
8140 *p_used = report_delta.used;
8141
8142 return notifier_to_errno(ret: rc);
8143}
8144
8145int netdev_offload_xstats_get(struct net_device *dev,
8146 enum netdev_offload_xstats_type type,
8147 struct rtnl_hw_stats64 *p_stats, bool *p_used,
8148 struct netlink_ext_ack *extack)
8149{
8150 ASSERT_RTNL();
8151
8152 if (p_stats)
8153 return netdev_offload_xstats_get_stats(dev, type, p_stats,
8154 p_used, extack);
8155 else
8156 return netdev_offload_xstats_get_used(dev, type, p_used,
8157 extack);
8158}
8159EXPORT_SYMBOL(netdev_offload_xstats_get);
8160
8161void
8162netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta,
8163 const struct rtnl_hw_stats64 *stats)
8164{
8165 report_delta->used = true;
8166 netdev_hw_stats64_add(dest: &report_delta->stats, src: stats);
8167}
8168EXPORT_SYMBOL(netdev_offload_xstats_report_delta);
8169
8170void
8171netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used)
8172{
8173 report_used->used = true;
8174}
8175EXPORT_SYMBOL(netdev_offload_xstats_report_used);
8176
8177void netdev_offload_xstats_push_delta(struct net_device *dev,
8178 enum netdev_offload_xstats_type type,
8179 const struct rtnl_hw_stats64 *p_stats)
8180{
8181 struct rtnl_hw_stats64 *stats;
8182
8183 ASSERT_RTNL();
8184
8185 stats = netdev_offload_xstats_get_ptr(dev, type);
8186 if (WARN_ON(!stats))
8187 return;
8188
8189 netdev_hw_stats64_add(dest: stats, src: p_stats);
8190}
8191EXPORT_SYMBOL(netdev_offload_xstats_push_delta);
8192
8193/**
8194 * netdev_get_xmit_slave - Get the xmit slave of master device
8195 * @dev: device
8196 * @skb: The packet
8197 * @all_slaves: assume all the slaves are active
8198 *
8199 * The reference counters are not incremented so the caller must be
8200 * careful with locks. The caller must hold RCU lock.
8201 * %NULL is returned if no slave is found.
8202 */
8203
8204struct net_device *netdev_get_xmit_slave(struct net_device *dev,
8205 struct sk_buff *skb,
8206 bool all_slaves)
8207{
8208 const struct net_device_ops *ops = dev->netdev_ops;
8209
8210 if (!ops->ndo_get_xmit_slave)
8211 return NULL;
8212 return ops->ndo_get_xmit_slave(dev, skb, all_slaves);
8213}
8214EXPORT_SYMBOL(netdev_get_xmit_slave);
8215
8216static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev,
8217 struct sock *sk)
8218{
8219 const struct net_device_ops *ops = dev->netdev_ops;
8220
8221 if (!ops->ndo_sk_get_lower_dev)
8222 return NULL;
8223 return ops->ndo_sk_get_lower_dev(dev, sk);
8224}
8225
8226/**
8227 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket
8228 * @dev: device
8229 * @sk: the socket
8230 *
8231 * %NULL is returned if no lower device is found.
8232 */
8233
8234struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev,
8235 struct sock *sk)
8236{
8237 struct net_device *lower;
8238
8239 lower = netdev_sk_get_lower_dev(dev, sk);
8240 while (lower) {
8241 dev = lower;
8242 lower = netdev_sk_get_lower_dev(dev, sk);
8243 }
8244
8245 return dev;
8246}
8247EXPORT_SYMBOL(netdev_sk_get_lowest_dev);
8248
8249static void netdev_adjacent_add_links(struct net_device *dev)
8250{
8251 struct netdev_adjacent *iter;
8252
8253 struct net *net = dev_net(dev);
8254
8255 list_for_each_entry(iter, &dev->adj_list.upper, list) {
8256 if (!net_eq(net1: net, net2: dev_net(dev: iter->dev)))
8257 continue;
8258 netdev_adjacent_sysfs_add(dev: iter->dev, adj_dev: dev,
8259 dev_list: &iter->dev->adj_list.lower);
8260 netdev_adjacent_sysfs_add(dev, adj_dev: iter->dev,
8261 dev_list: &dev->adj_list.upper);
8262 }
8263
8264 list_for_each_entry(iter, &dev->adj_list.lower, list) {
8265 if (!net_eq(net1: net, net2: dev_net(dev: iter->dev)))
8266 continue;
8267 netdev_adjacent_sysfs_add(dev: iter->dev, adj_dev: dev,
8268 dev_list: &iter->dev->adj_list.upper);
8269 netdev_adjacent_sysfs_add(dev, adj_dev: iter->dev,
8270 dev_list: &dev->adj_list.lower);
8271 }
8272}
8273
8274static void netdev_adjacent_del_links(struct net_device *dev)
8275{
8276 struct netdev_adjacent *iter;
8277
8278 struct net *net = dev_net(dev);
8279
8280 list_for_each_entry(iter, &dev->adj_list.upper, list) {
8281 if (!net_eq(net1: net, net2: dev_net(dev: iter->dev)))
8282 continue;
8283 netdev_adjacent_sysfs_del(dev: iter->dev, name: dev->name,
8284 dev_list: &iter->dev->adj_list.lower);
8285 netdev_adjacent_sysfs_del(dev, name: iter->dev->name,
8286 dev_list: &dev->adj_list.upper);
8287 }
8288
8289 list_for_each_entry(iter, &dev->adj_list.lower, list) {
8290 if (!net_eq(net1: net, net2: dev_net(dev: iter->dev)))
8291 continue;
8292 netdev_adjacent_sysfs_del(dev: iter->dev, name: dev->name,
8293 dev_list: &iter->dev->adj_list.upper);
8294 netdev_adjacent_sysfs_del(dev, name: iter->dev->name,
8295 dev_list: &dev->adj_list.lower);
8296 }
8297}
8298
8299void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
8300{
8301 struct netdev_adjacent *iter;
8302
8303 struct net *net = dev_net(dev);
8304
8305 list_for_each_entry(iter, &dev->adj_list.upper, list) {
8306 if (!net_eq(net1: net, net2: dev_net(dev: iter->dev)))
8307 continue;
8308 netdev_adjacent_sysfs_del(dev: iter->dev, name: oldname,
8309 dev_list: &iter->dev->adj_list.lower);
8310 netdev_adjacent_sysfs_add(dev: iter->dev, adj_dev: dev,
8311 dev_list: &iter->dev->adj_list.lower);
8312 }
8313
8314 list_for_each_entry(iter, &dev->adj_list.lower, list) {
8315 if (!net_eq(net1: net, net2: dev_net(dev: iter->dev)))
8316 continue;
8317 netdev_adjacent_sysfs_del(dev: iter->dev, name: oldname,
8318 dev_list: &iter->dev->adj_list.upper);
8319 netdev_adjacent_sysfs_add(dev: iter->dev, adj_dev: dev,
8320 dev_list: &iter->dev->adj_list.upper);
8321 }
8322}
8323
8324void *netdev_lower_dev_get_private(struct net_device *dev,
8325 struct net_device *lower_dev)
8326{
8327 struct netdev_adjacent *lower;
8328
8329 if (!lower_dev)
8330 return NULL;
8331 lower = __netdev_find_adj(adj_dev: lower_dev, adj_list: &dev->adj_list.lower);
8332 if (!lower)
8333 return NULL;
8334
8335 return lower->private;
8336}
8337EXPORT_SYMBOL(netdev_lower_dev_get_private);
8338
8339
8340/**
8341 * netdev_lower_state_changed - Dispatch event about lower device state change
8342 * @lower_dev: device
8343 * @lower_state_info: state to dispatch
8344 *
8345 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info.
8346 * The caller must hold the RTNL lock.
8347 */
8348void netdev_lower_state_changed(struct net_device *lower_dev,
8349 void *lower_state_info)
8350{
8351 struct netdev_notifier_changelowerstate_info changelowerstate_info = {
8352 .info.dev = lower_dev,
8353 };
8354
8355 ASSERT_RTNL();
8356 changelowerstate_info.lower_state_info = lower_state_info;
8357 call_netdevice_notifiers_info(val: NETDEV_CHANGELOWERSTATE,
8358 info: &changelowerstate_info.info);
8359}
8360EXPORT_SYMBOL(netdev_lower_state_changed);
8361
8362static void dev_change_rx_flags(struct net_device *dev, int flags)
8363{
8364 const struct net_device_ops *ops = dev->netdev_ops;
8365
8366 if (ops->ndo_change_rx_flags)
8367 ops->ndo_change_rx_flags(dev, flags);
8368}
8369
8370static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
8371{
8372 unsigned int old_flags = dev->flags;
8373 kuid_t uid;
8374 kgid_t gid;
8375
8376 ASSERT_RTNL();
8377
8378 dev->flags |= IFF_PROMISC;
8379 dev->promiscuity += inc;
8380 if (dev->promiscuity == 0) {
8381 /*
8382 * Avoid overflow.
8383 * If inc causes overflow, untouch promisc and return error.
8384 */
8385 if (inc < 0)
8386 dev->flags &= ~IFF_PROMISC;
8387 else {
8388 dev->promiscuity -= inc;
8389 netdev_warn(dev, format: "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n");
8390 return -EOVERFLOW;
8391 }
8392 }
8393 if (dev->flags != old_flags) {
8394 netdev_info(dev, format: "%s promiscuous mode\n",
8395 dev->flags & IFF_PROMISC ? "entered" : "left");
8396 if (audit_enabled) {
8397 current_uid_gid(&uid, &gid);
8398 audit_log(ctx: audit_context(), GFP_ATOMIC,
8399 AUDIT_ANOM_PROMISCUOUS,
8400 fmt: "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
8401 dev->name, (dev->flags & IFF_PROMISC),
8402 (old_flags & IFF_PROMISC),
8403 from_kuid(to: &init_user_ns, uid: audit_get_loginuid(current)),
8404 from_kuid(to: &init_user_ns, uid),
8405 from_kgid(to: &init_user_ns, gid),
8406 audit_get_sessionid(current));
8407 }
8408
8409 dev_change_rx_flags(dev, IFF_PROMISC);
8410 }
8411 if (notify)
8412 __dev_notify_flags(dev, old_flags, IFF_PROMISC, portid: 0, NULL);
8413 return 0;
8414}
8415
8416/**
8417 * dev_set_promiscuity - update promiscuity count on a device
8418 * @dev: device
8419 * @inc: modifier
8420 *
8421 * Add or remove promiscuity from a device. While the count in the device
8422 * remains above zero the interface remains promiscuous. Once it hits zero
8423 * the device reverts back to normal filtering operation. A negative inc
8424 * value is used to drop promiscuity on the device.
8425 * Return 0 if successful or a negative errno code on error.
8426 */
8427int dev_set_promiscuity(struct net_device *dev, int inc)
8428{
8429 unsigned int old_flags = dev->flags;
8430 int err;
8431
8432 err = __dev_set_promiscuity(dev, inc, notify: true);
8433 if (err < 0)
8434 return err;
8435 if (dev->flags != old_flags)
8436 dev_set_rx_mode(dev);
8437 return err;
8438}
8439EXPORT_SYMBOL(dev_set_promiscuity);
8440
8441static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
8442{
8443 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
8444
8445 ASSERT_RTNL();
8446
8447 dev->flags |= IFF_ALLMULTI;
8448 dev->allmulti += inc;
8449 if (dev->allmulti == 0) {
8450 /*
8451 * Avoid overflow.
8452 * If inc causes overflow, untouch allmulti and return error.
8453 */
8454 if (inc < 0)
8455 dev->flags &= ~IFF_ALLMULTI;
8456 else {
8457 dev->allmulti -= inc;
8458 netdev_warn(dev, format: "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n");
8459 return -EOVERFLOW;
8460 }
8461 }
8462 if (dev->flags ^ old_flags) {
8463 netdev_info(dev, format: "%s allmulticast mode\n",
8464 dev->flags & IFF_ALLMULTI ? "entered" : "left");
8465 dev_change_rx_flags(dev, IFF_ALLMULTI);
8466 dev_set_rx_mode(dev);
8467 if (notify)
8468 __dev_notify_flags(dev, old_flags,
8469 gchanges: dev->gflags ^ old_gflags, portid: 0, NULL);
8470 }
8471 return 0;
8472}
8473
8474/**
8475 * dev_set_allmulti - update allmulti count on a device
8476 * @dev: device
8477 * @inc: modifier
8478 *
8479 * Add or remove reception of all multicast frames to a device. While the
8480 * count in the device remains above zero the interface remains listening
8481 * to all interfaces. Once it hits zero the device reverts back to normal
8482 * filtering operation. A negative @inc value is used to drop the counter
8483 * when releasing a resource needing all multicasts.
8484 * Return 0 if successful or a negative errno code on error.
8485 */
8486
8487int dev_set_allmulti(struct net_device *dev, int inc)
8488{
8489 return __dev_set_allmulti(dev, inc, notify: true);
8490}
8491EXPORT_SYMBOL(dev_set_allmulti);
8492
8493/*
8494 * Upload unicast and multicast address lists to device and
8495 * configure RX filtering. When the device doesn't support unicast
8496 * filtering it is put in promiscuous mode while unicast addresses
8497 * are present.
8498 */
8499void __dev_set_rx_mode(struct net_device *dev)
8500{
8501 const struct net_device_ops *ops = dev->netdev_ops;
8502
8503 /* dev_open will call this function so the list will stay sane. */
8504 if (!(dev->flags&IFF_UP))
8505 return;
8506
8507 if (!netif_device_present(dev))
8508 return;
8509
8510 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
8511 /* Unicast addresses changes may only happen under the rtnl,
8512 * therefore calling __dev_set_promiscuity here is safe.
8513 */
8514 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
8515 __dev_set_promiscuity(dev, inc: 1, notify: false);
8516 dev->uc_promisc = true;
8517 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
8518 __dev_set_promiscuity(dev, inc: -1, notify: false);
8519 dev->uc_promisc = false;
8520 }
8521 }
8522
8523 if (ops->ndo_set_rx_mode)
8524 ops->ndo_set_rx_mode(dev);
8525}
8526
8527void dev_set_rx_mode(struct net_device *dev)
8528{
8529 netif_addr_lock_bh(dev);
8530 __dev_set_rx_mode(dev);
8531 netif_addr_unlock_bh(dev);
8532}
8533
8534/**
8535 * dev_get_flags - get flags reported to userspace
8536 * @dev: device
8537 *
8538 * Get the combination of flag bits exported through APIs to userspace.
8539 */
8540unsigned int dev_get_flags(const struct net_device *dev)
8541{
8542 unsigned int flags;
8543
8544 flags = (dev->flags & ~(IFF_PROMISC |
8545 IFF_ALLMULTI |
8546 IFF_RUNNING |
8547 IFF_LOWER_UP |
8548 IFF_DORMANT)) |
8549 (dev->gflags & (IFF_PROMISC |
8550 IFF_ALLMULTI));
8551
8552 if (netif_running(dev)) {
8553 if (netif_oper_up(dev))
8554 flags |= IFF_RUNNING;
8555 if (netif_carrier_ok(dev))
8556 flags |= IFF_LOWER_UP;
8557 if (netif_dormant(dev))
8558 flags |= IFF_DORMANT;
8559 }
8560
8561 return flags;
8562}
8563EXPORT_SYMBOL(dev_get_flags);
8564
8565int __dev_change_flags(struct net_device *dev, unsigned int flags,
8566 struct netlink_ext_ack *extack)
8567{
8568 unsigned int old_flags = dev->flags;
8569 int ret;
8570
8571 ASSERT_RTNL();
8572
8573 /*
8574 * Set the flags on our device.
8575 */
8576
8577 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
8578 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
8579 IFF_AUTOMEDIA)) |
8580 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
8581 IFF_ALLMULTI));
8582
8583 /*
8584 * Load in the correct multicast list now the flags have changed.
8585 */
8586
8587 if ((old_flags ^ flags) & IFF_MULTICAST)
8588 dev_change_rx_flags(dev, IFF_MULTICAST);
8589
8590 dev_set_rx_mode(dev);
8591
8592 /*
8593 * Have we downed the interface. We handle IFF_UP ourselves
8594 * according to user attempts to set it, rather than blindly
8595 * setting it.
8596 */
8597
8598 ret = 0;
8599 if ((old_flags ^ flags) & IFF_UP) {
8600 if (old_flags & IFF_UP)
8601 __dev_close(dev);
8602 else
8603 ret = __dev_open(dev, extack);
8604 }
8605
8606 if ((flags ^ dev->gflags) & IFF_PROMISC) {
8607 int inc = (flags & IFF_PROMISC) ? 1 : -1;
8608 unsigned int old_flags = dev->flags;
8609
8610 dev->gflags ^= IFF_PROMISC;
8611
8612 if (__dev_set_promiscuity(dev, inc, notify: false) >= 0)
8613 if (dev->flags != old_flags)
8614 dev_set_rx_mode(dev);
8615 }
8616
8617 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
8618 * is important. Some (broken) drivers set IFF_PROMISC, when
8619 * IFF_ALLMULTI is requested not asking us and not reporting.
8620 */
8621 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
8622 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
8623
8624 dev->gflags ^= IFF_ALLMULTI;
8625 __dev_set_allmulti(dev, inc, notify: false);
8626 }
8627
8628 return ret;
8629}
8630
8631void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
8632 unsigned int gchanges, u32 portid,
8633 const struct nlmsghdr *nlh)
8634{
8635 unsigned int changes = dev->flags ^ old_flags;
8636
8637 if (gchanges)
8638 rtmsg_ifinfo(RTM_NEWLINK, dev, change: gchanges, GFP_ATOMIC, portid, nlh);
8639
8640 if (changes & IFF_UP) {
8641 if (dev->flags & IFF_UP)
8642 call_netdevice_notifiers(NETDEV_UP, dev);
8643 else
8644 call_netdevice_notifiers(NETDEV_DOWN, dev);
8645 }
8646
8647 if (dev->flags & IFF_UP &&
8648 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
8649 struct netdev_notifier_change_info change_info = {
8650 .info = {
8651 .dev = dev,
8652 },
8653 .flags_changed = changes,
8654 };
8655
8656 call_netdevice_notifiers_info(val: NETDEV_CHANGE, info: &change_info.info);
8657 }
8658}
8659
8660/**
8661 * dev_change_flags - change device settings
8662 * @dev: device
8663 * @flags: device state flags
8664 * @extack: netlink extended ack
8665 *
8666 * Change settings on device based state flags. The flags are
8667 * in the userspace exported format.
8668 */
8669int dev_change_flags(struct net_device *dev, unsigned int flags,
8670 struct netlink_ext_ack *extack)
8671{
8672 int ret;
8673 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
8674
8675 ret = __dev_change_flags(dev, flags, extack);
8676 if (ret < 0)
8677 return ret;
8678
8679 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
8680 __dev_notify_flags(dev, old_flags, gchanges: changes, portid: 0, NULL);
8681 return ret;
8682}
8683EXPORT_SYMBOL(dev_change_flags);
8684
8685int __dev_set_mtu(struct net_device *dev, int new_mtu)
8686{
8687 const struct net_device_ops *ops = dev->netdev_ops;
8688
8689 if (ops->ndo_change_mtu)
8690 return ops->ndo_change_mtu(dev, new_mtu);
8691
8692 /* Pairs with all the lockless reads of dev->mtu in the stack */
8693 WRITE_ONCE(dev->mtu, new_mtu);
8694 return 0;
8695}
8696EXPORT_SYMBOL(__dev_set_mtu);
8697
8698int dev_validate_mtu(struct net_device *dev, int new_mtu,
8699 struct netlink_ext_ack *extack)
8700{
8701 /* MTU must be positive, and in range */
8702 if (new_mtu < 0 || new_mtu < dev->min_mtu) {
8703 NL_SET_ERR_MSG(extack, "mtu less than device minimum");
8704 return -EINVAL;
8705 }
8706
8707 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
8708 NL_SET_ERR_MSG(extack, "mtu greater than device maximum");
8709 return -EINVAL;
8710 }
8711 return 0;
8712}
8713
8714/**
8715 * dev_set_mtu_ext - Change maximum transfer unit
8716 * @dev: device
8717 * @new_mtu: new transfer unit
8718 * @extack: netlink extended ack
8719 *
8720 * Change the maximum transfer size of the network device.
8721 */
8722int dev_set_mtu_ext(struct net_device *dev, int new_mtu,
8723 struct netlink_ext_ack *extack)
8724{
8725 int err, orig_mtu;
8726
8727 if (new_mtu == dev->mtu)
8728 return 0;
8729
8730 err = dev_validate_mtu(dev, new_mtu, extack);
8731 if (err)
8732 return err;
8733
8734 if (!netif_device_present(dev))
8735 return -ENODEV;
8736
8737 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
8738 err = notifier_to_errno(ret: err);
8739 if (err)
8740 return err;
8741
8742 orig_mtu = dev->mtu;
8743 err = __dev_set_mtu(dev, new_mtu);
8744
8745 if (!err) {
8746 err = call_netdevice_notifiers_mtu(val: NETDEV_CHANGEMTU, dev,
8747 arg: orig_mtu);
8748 err = notifier_to_errno(ret: err);
8749 if (err) {
8750 /* setting mtu back and notifying everyone again,
8751 * so that they have a chance to revert changes.
8752 */
8753 __dev_set_mtu(dev, orig_mtu);
8754 call_netdevice_notifiers_mtu(val: NETDEV_CHANGEMTU, dev,
8755 arg: new_mtu);
8756 }
8757 }
8758 return err;
8759}
8760
8761int dev_set_mtu(struct net_device *dev, int new_mtu)
8762{
8763 struct netlink_ext_ack extack;
8764 int err;
8765
8766 memset(&extack, 0, sizeof(extack));
8767 err = dev_set_mtu_ext(dev, new_mtu, extack: &extack);
8768 if (err && extack._msg)
8769 net_err_ratelimited("%s: %s\n", dev->name, extack._msg);
8770 return err;
8771}
8772EXPORT_SYMBOL(dev_set_mtu);
8773
8774/**
8775 * dev_change_tx_queue_len - Change TX queue length of a netdevice
8776 * @dev: device
8777 * @new_len: new tx queue length
8778 */
8779int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len)
8780{
8781 unsigned int orig_len = dev->tx_queue_len;
8782 int res;
8783
8784 if (new_len != (unsigned int)new_len)
8785 return -ERANGE;
8786
8787 if (new_len != orig_len) {
8788 dev->tx_queue_len = new_len;
8789 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev);
8790 res = notifier_to_errno(ret: res);
8791 if (res)
8792 goto err_rollback;
8793 res = dev_qdisc_change_tx_queue_len(dev);
8794 if (res)
8795 goto err_rollback;
8796 }
8797
8798 return 0;
8799
8800err_rollback:
8801 netdev_err(dev, format: "refused to change device tx_queue_len\n");
8802 dev->tx_queue_len = orig_len;
8803 return res;
8804}
8805
8806/**
8807 * dev_set_group - Change group this device belongs to
8808 * @dev: device
8809 * @new_group: group this device should belong to
8810 */
8811void dev_set_group(struct net_device *dev, int new_group)
8812{
8813 dev->group = new_group;
8814}
8815
8816/**
8817 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR.
8818 * @dev: device
8819 * @addr: new address
8820 * @extack: netlink extended ack
8821 */
8822int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr,
8823 struct netlink_ext_ack *extack)
8824{
8825 struct netdev_notifier_pre_changeaddr_info info = {
8826 .info.dev = dev,
8827 .info.extack = extack,
8828 .dev_addr = addr,
8829 };
8830 int rc;
8831
8832 rc = call_netdevice_notifiers_info(val: NETDEV_PRE_CHANGEADDR, info: &info.info);
8833 return notifier_to_errno(ret: rc);
8834}
8835EXPORT_SYMBOL(dev_pre_changeaddr_notify);
8836
8837/**
8838 * dev_set_mac_address - Change Media Access Control Address
8839 * @dev: device
8840 * @sa: new address
8841 * @extack: netlink extended ack
8842 *
8843 * Change the hardware (MAC) address of the device
8844 */
8845int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa,
8846 struct netlink_ext_ack *extack)
8847{
8848 const struct net_device_ops *ops = dev->netdev_ops;
8849 int err;
8850
8851 if (!ops->ndo_set_mac_address)
8852 return -EOPNOTSUPP;
8853 if (sa->sa_family != dev->type)
8854 return -EINVAL;
8855 if (!netif_device_present(dev))
8856 return -ENODEV;
8857 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack);
8858 if (err)
8859 return err;
8860 if (memcmp(p: dev->dev_addr, q: sa->sa_data, size: dev->addr_len)) {
8861 err = ops->ndo_set_mac_address(dev, sa);
8862 if (err)
8863 return err;
8864 }
8865 dev->addr_assign_type = NET_ADDR_SET;
8866 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
8867 add_device_randomness(buf: dev->dev_addr, len: dev->addr_len);
8868 return 0;
8869}
8870EXPORT_SYMBOL(dev_set_mac_address);
8871
8872static DECLARE_RWSEM(dev_addr_sem);
8873
8874int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
8875 struct netlink_ext_ack *extack)
8876{
8877 int ret;
8878
8879 down_write(sem: &dev_addr_sem);
8880 ret = dev_set_mac_address(dev, sa, extack);
8881 up_write(sem: &dev_addr_sem);
8882 return ret;
8883}
8884EXPORT_SYMBOL(dev_set_mac_address_user);
8885
8886int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name)
8887{
8888 size_t size = sizeof(sa->sa_data_min);
8889 struct net_device *dev;
8890 int ret = 0;
8891
8892 down_read(sem: &dev_addr_sem);
8893 rcu_read_lock();
8894
8895 dev = dev_get_by_name_rcu(net, dev_name);
8896 if (!dev) {
8897 ret = -ENODEV;
8898 goto unlock;
8899 }
8900 if (!dev->addr_len)
8901 memset(sa->sa_data, 0, size);
8902 else
8903 memcpy(sa->sa_data, dev->dev_addr,
8904 min_t(size_t, size, dev->addr_len));
8905 sa->sa_family = dev->type;
8906
8907unlock:
8908 rcu_read_unlock();
8909 up_read(sem: &dev_addr_sem);
8910 return ret;
8911}
8912EXPORT_SYMBOL(dev_get_mac_address);
8913
8914/**
8915 * dev_change_carrier - Change device carrier
8916 * @dev: device
8917 * @new_carrier: new value
8918 *
8919 * Change device carrier
8920 */
8921int dev_change_carrier(struct net_device *dev, bool new_carrier)
8922{
8923 const struct net_device_ops *ops = dev->netdev_ops;
8924
8925 if (!ops->ndo_change_carrier)
8926 return -EOPNOTSUPP;
8927 if (!netif_device_present(dev))
8928 return -ENODEV;
8929 return ops->ndo_change_carrier(dev, new_carrier);
8930}
8931
8932/**
8933 * dev_get_phys_port_id - Get device physical port ID
8934 * @dev: device
8935 * @ppid: port ID
8936 *
8937 * Get device physical port ID
8938 */
8939int dev_get_phys_port_id(struct net_device *dev,
8940 struct netdev_phys_item_id *ppid)
8941{
8942 const struct net_device_ops *ops = dev->netdev_ops;
8943
8944 if (!ops->ndo_get_phys_port_id)
8945 return -EOPNOTSUPP;
8946 return ops->ndo_get_phys_port_id(dev, ppid);
8947}
8948
8949/**
8950 * dev_get_phys_port_name - Get device physical port name
8951 * @dev: device
8952 * @name: port name
8953 * @len: limit of bytes to copy to name
8954 *
8955 * Get device physical port name
8956 */
8957int dev_get_phys_port_name(struct net_device *dev,
8958 char *name, size_t len)
8959{
8960 const struct net_device_ops *ops = dev->netdev_ops;
8961 int err;
8962
8963 if (ops->ndo_get_phys_port_name) {
8964 err = ops->ndo_get_phys_port_name(dev, name, len);
8965 if (err != -EOPNOTSUPP)
8966 return err;
8967 }
8968 return devlink_compat_phys_port_name_get(dev, name, len);
8969}
8970
8971/**
8972 * dev_get_port_parent_id - Get the device's port parent identifier
8973 * @dev: network device
8974 * @ppid: pointer to a storage for the port's parent identifier
8975 * @recurse: allow/disallow recursion to lower devices
8976 *
8977 * Get the devices's port parent identifier
8978 */
8979int dev_get_port_parent_id(struct net_device *dev,
8980 struct netdev_phys_item_id *ppid,
8981 bool recurse)
8982{
8983 const struct net_device_ops *ops = dev->netdev_ops;
8984 struct netdev_phys_item_id first = { };
8985 struct net_device *lower_dev;
8986 struct list_head *iter;
8987 int err;
8988
8989 if (ops->ndo_get_port_parent_id) {
8990 err = ops->ndo_get_port_parent_id(dev, ppid);
8991 if (err != -EOPNOTSUPP)
8992 return err;
8993 }
8994
8995 err = devlink_compat_switch_id_get(dev, ppid);
8996 if (!recurse || err != -EOPNOTSUPP)
8997 return err;
8998
8999 netdev_for_each_lower_dev(dev, lower_dev, iter) {
9000 err = dev_get_port_parent_id(dev: lower_dev, ppid, recurse: true);
9001 if (err)
9002 break;
9003 if (!first.id_len)
9004 first = *ppid;
9005 else if (memcmp(p: &first, q: ppid, size: sizeof(*ppid)))
9006 return -EOPNOTSUPP;
9007 }
9008
9009 return err;
9010}
9011EXPORT_SYMBOL(dev_get_port_parent_id);
9012
9013/**
9014 * netdev_port_same_parent_id - Indicate if two network devices have
9015 * the same port parent identifier
9016 * @a: first network device
9017 * @b: second network device
9018 */
9019bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b)
9020{
9021 struct netdev_phys_item_id a_id = { };
9022 struct netdev_phys_item_id b_id = { };
9023
9024 if (dev_get_port_parent_id(a, &a_id, true) ||
9025 dev_get_port_parent_id(b, &b_id, true))
9026 return false;
9027
9028 return netdev_phys_item_id_same(a: &a_id, b: &b_id);
9029}
9030EXPORT_SYMBOL(netdev_port_same_parent_id);
9031
9032static void netdev_dpll_pin_assign(struct net_device *dev, struct dpll_pin *dpll_pin)
9033{
9034#if IS_ENABLED(CONFIG_DPLL)
9035 rtnl_lock();
9036 dev->dpll_pin = dpll_pin;
9037 rtnl_unlock();
9038#endif
9039}
9040
9041void netdev_dpll_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin)
9042{
9043 WARN_ON(!dpll_pin);
9044 netdev_dpll_pin_assign(dev, dpll_pin);
9045}
9046EXPORT_SYMBOL(netdev_dpll_pin_set);
9047
9048void netdev_dpll_pin_clear(struct net_device *dev)
9049{
9050 netdev_dpll_pin_assign(dev, NULL);
9051}
9052EXPORT_SYMBOL(netdev_dpll_pin_clear);
9053
9054/**
9055 * dev_change_proto_down - set carrier according to proto_down.
9056 *
9057 * @dev: device
9058 * @proto_down: new value
9059 */
9060int dev_change_proto_down(struct net_device *dev, bool proto_down)
9061{
9062 if (!(dev->priv_flags & IFF_CHANGE_PROTO_DOWN))
9063 return -EOPNOTSUPP;
9064 if (!netif_device_present(dev))
9065 return -ENODEV;
9066 if (proto_down)
9067 netif_carrier_off(dev);
9068 else
9069 netif_carrier_on(dev);
9070 dev->proto_down = proto_down;
9071 return 0;
9072}
9073
9074/**
9075 * dev_change_proto_down_reason - proto down reason
9076 *
9077 * @dev: device
9078 * @mask: proto down mask
9079 * @value: proto down value
9080 */
9081void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask,
9082 u32 value)
9083{
9084 int b;
9085
9086 if (!mask) {
9087 dev->proto_down_reason = value;
9088 } else {
9089 for_each_set_bit(b, &mask, 32) {
9090 if (value & (1 << b))
9091 dev->proto_down_reason |= BIT(b);
9092 else
9093 dev->proto_down_reason &= ~BIT(b);
9094 }
9095 }
9096}
9097
9098struct bpf_xdp_link {
9099 struct bpf_link link;
9100 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */
9101 int flags;
9102};
9103
9104static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags)
9105{
9106 if (flags & XDP_FLAGS_HW_MODE)
9107 return XDP_MODE_HW;
9108 if (flags & XDP_FLAGS_DRV_MODE)
9109 return XDP_MODE_DRV;
9110 if (flags & XDP_FLAGS_SKB_MODE)
9111 return XDP_MODE_SKB;
9112 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB;
9113}
9114
9115static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode)
9116{
9117 switch (mode) {
9118 case XDP_MODE_SKB:
9119 return generic_xdp_install;
9120 case XDP_MODE_DRV:
9121 case XDP_MODE_HW:
9122 return dev->netdev_ops->ndo_bpf;
9123 default:
9124 return NULL;
9125 }
9126}
9127
9128static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev,
9129 enum bpf_xdp_mode mode)
9130{
9131 return dev->xdp_state[mode].link;
9132}
9133
9134static struct bpf_prog *dev_xdp_prog(struct net_device *dev,
9135 enum bpf_xdp_mode mode)
9136{
9137 struct bpf_xdp_link *link = dev_xdp_link(dev, mode);
9138
9139 if (link)
9140 return link->link.prog;
9141 return dev->xdp_state[mode].prog;
9142}
9143
9144u8 dev_xdp_prog_count(struct net_device *dev)
9145{
9146 u8 count = 0;
9147 int i;
9148
9149 for (i = 0; i < __MAX_XDP_MODE; i++)
9150 if (dev->xdp_state[i].prog || dev->xdp_state[i].link)
9151 count++;
9152 return count;
9153}
9154EXPORT_SYMBOL_GPL(dev_xdp_prog_count);
9155
9156u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode)
9157{
9158 struct bpf_prog *prog = dev_xdp_prog(dev, mode);
9159
9160 return prog ? prog->aux->id : 0;
9161}
9162
9163static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode,
9164 struct bpf_xdp_link *link)
9165{
9166 dev->xdp_state[mode].link = link;
9167 dev->xdp_state[mode].prog = NULL;
9168}
9169
9170static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode,
9171 struct bpf_prog *prog)
9172{
9173 dev->xdp_state[mode].link = NULL;
9174 dev->xdp_state[mode].prog = prog;
9175}
9176
9177static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode,
9178 bpf_op_t bpf_op, struct netlink_ext_ack *extack,
9179 u32 flags, struct bpf_prog *prog)
9180{
9181 struct netdev_bpf xdp;
9182 int err;
9183
9184 memset(&xdp, 0, sizeof(xdp));
9185 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG;
9186 xdp.extack = extack;
9187 xdp.flags = flags;
9188 xdp.prog = prog;
9189
9190 /* Drivers assume refcnt is already incremented (i.e, prog pointer is
9191 * "moved" into driver), so they don't increment it on their own, but
9192 * they do decrement refcnt when program is detached or replaced.
9193 * Given net_device also owns link/prog, we need to bump refcnt here
9194 * to prevent drivers from underflowing it.
9195 */
9196 if (prog)
9197 bpf_prog_inc(prog);
9198 err = bpf_op(dev, &xdp);
9199 if (err) {
9200 if (prog)
9201 bpf_prog_put(prog);
9202 return err;
9203 }
9204
9205 if (mode != XDP_MODE_HW)
9206 bpf_prog_change_xdp(prev_prog: dev_xdp_prog(dev, mode), prog);
9207
9208 return 0;
9209}
9210
9211static void dev_xdp_uninstall(struct net_device *dev)
9212{
9213 struct bpf_xdp_link *link;
9214 struct bpf_prog *prog;
9215 enum bpf_xdp_mode mode;
9216 bpf_op_t bpf_op;
9217
9218 ASSERT_RTNL();
9219
9220 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) {
9221 prog = dev_xdp_prog(dev, mode);
9222 if (!prog)
9223 continue;
9224
9225 bpf_op = dev_xdp_bpf_op(dev, mode);
9226 if (!bpf_op)
9227 continue;
9228
9229 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL));
9230
9231 /* auto-detach link from net device */
9232 link = dev_xdp_link(dev, mode);
9233 if (link)
9234 link->dev = NULL;
9235 else
9236 bpf_prog_put(prog);
9237
9238 dev_xdp_set_link(dev, mode, NULL);
9239 }
9240}
9241
9242static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack,
9243 struct bpf_xdp_link *link, struct bpf_prog *new_prog,
9244 struct bpf_prog *old_prog, u32 flags)
9245{
9246 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES);
9247 struct bpf_prog *cur_prog;
9248 struct net_device *upper;
9249 struct list_head *iter;
9250 enum bpf_xdp_mode mode;
9251 bpf_op_t bpf_op;
9252 int err;
9253
9254 ASSERT_RTNL();
9255
9256 /* either link or prog attachment, never both */
9257 if (link && (new_prog || old_prog))
9258 return -EINVAL;
9259 /* link supports only XDP mode flags */
9260 if (link && (flags & ~XDP_FLAGS_MODES)) {
9261 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment");
9262 return -EINVAL;
9263 }
9264 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */
9265 if (num_modes > 1) {
9266 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set");
9267 return -EINVAL;
9268 }
9269 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */
9270 if (!num_modes && dev_xdp_prog_count(dev) > 1) {
9271 NL_SET_ERR_MSG(extack,
9272 "More than one program loaded, unset mode is ambiguous");
9273 return -EINVAL;
9274 }
9275 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */
9276 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) {
9277 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified");
9278 return -EINVAL;
9279 }
9280
9281 mode = dev_xdp_mode(dev, flags);
9282 /* can't replace attached link */
9283 if (dev_xdp_link(dev, mode)) {
9284 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link");
9285 return -EBUSY;
9286 }
9287
9288 /* don't allow if an upper device already has a program */
9289 netdev_for_each_upper_dev_rcu(dev, upper, iter) {
9290 if (dev_xdp_prog_count(upper) > 0) {
9291 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program");
9292 return -EEXIST;
9293 }
9294 }
9295
9296 cur_prog = dev_xdp_prog(dev, mode);
9297 /* can't replace attached prog with link */
9298 if (link && cur_prog) {
9299 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link");
9300 return -EBUSY;
9301 }
9302 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) {
9303 NL_SET_ERR_MSG(extack, "Active program does not match expected");
9304 return -EEXIST;
9305 }
9306
9307 /* put effective new program into new_prog */
9308 if (link)
9309 new_prog = link->link.prog;
9310
9311 if (new_prog) {
9312 bool offload = mode == XDP_MODE_HW;
9313 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB
9314 ? XDP_MODE_DRV : XDP_MODE_SKB;
9315
9316 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) {
9317 NL_SET_ERR_MSG(extack, "XDP program already attached");
9318 return -EBUSY;
9319 }
9320 if (!offload && dev_xdp_prog(dev, mode: other_mode)) {
9321 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time");
9322 return -EEXIST;
9323 }
9324 if (!offload && bpf_prog_is_offloaded(aux: new_prog->aux)) {
9325 NL_SET_ERR_MSG(extack, "Using offloaded program without HW_MODE flag is not supported");
9326 return -EINVAL;
9327 }
9328 if (bpf_prog_is_dev_bound(aux: new_prog->aux) && !bpf_offload_dev_match(prog: new_prog, netdev: dev)) {
9329 NL_SET_ERR_MSG(extack, "Program bound to different device");
9330 return -EINVAL;
9331 }
9332 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) {
9333 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device");
9334 return -EINVAL;
9335 }
9336 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) {
9337 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device");
9338 return -EINVAL;
9339 }
9340 }
9341
9342 /* don't call drivers if the effective program didn't change */
9343 if (new_prog != cur_prog) {
9344 bpf_op = dev_xdp_bpf_op(dev, mode);
9345 if (!bpf_op) {
9346 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode");
9347 return -EOPNOTSUPP;
9348 }
9349
9350 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, prog: new_prog);
9351 if (err)
9352 return err;
9353 }
9354
9355 if (link)
9356 dev_xdp_set_link(dev, mode, link);
9357 else
9358 dev_xdp_set_prog(dev, mode, prog: new_prog);
9359 if (cur_prog)
9360 bpf_prog_put(prog: cur_prog);
9361
9362 return 0;
9363}
9364
9365static int dev_xdp_attach_link(struct net_device *dev,
9366 struct netlink_ext_ack *extack,
9367 struct bpf_xdp_link *link)
9368{
9369 return dev_xdp_attach(dev, extack, link, NULL, NULL, flags: link->flags);
9370}
9371
9372static int dev_xdp_detach_link(struct net_device *dev,
9373 struct netlink_ext_ack *extack,
9374 struct bpf_xdp_link *link)
9375{
9376 enum bpf_xdp_mode mode;
9377 bpf_op_t bpf_op;
9378
9379 ASSERT_RTNL();
9380
9381 mode = dev_xdp_mode(dev, flags: link->flags);
9382 if (dev_xdp_link(dev, mode) != link)
9383 return -EINVAL;
9384
9385 bpf_op = dev_xdp_bpf_op(dev, mode);
9386 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL));
9387 dev_xdp_set_link(dev, mode, NULL);
9388 return 0;
9389}
9390
9391static void bpf_xdp_link_release(struct bpf_link *link)
9392{
9393 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
9394
9395 rtnl_lock();
9396
9397 /* if racing with net_device's tear down, xdp_link->dev might be
9398 * already NULL, in which case link was already auto-detached
9399 */
9400 if (xdp_link->dev) {
9401 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link));
9402 xdp_link->dev = NULL;
9403 }
9404
9405 rtnl_unlock();
9406}
9407
9408static int bpf_xdp_link_detach(struct bpf_link *link)
9409{
9410 bpf_xdp_link_release(link);
9411 return 0;
9412}
9413
9414static void bpf_xdp_link_dealloc(struct bpf_link *link)
9415{
9416 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
9417
9418 kfree(objp: xdp_link);
9419}
9420
9421static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link,
9422 struct seq_file *seq)
9423{
9424 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
9425 u32 ifindex = 0;
9426
9427 rtnl_lock();
9428 if (xdp_link->dev)
9429 ifindex = xdp_link->dev->ifindex;
9430 rtnl_unlock();
9431
9432 seq_printf(m: seq, fmt: "ifindex:\t%u\n", ifindex);
9433}
9434
9435static int bpf_xdp_link_fill_link_info(const struct bpf_link *link,
9436 struct bpf_link_info *info)
9437{
9438 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
9439 u32 ifindex = 0;
9440
9441 rtnl_lock();
9442 if (xdp_link->dev)
9443 ifindex = xdp_link->dev->ifindex;
9444 rtnl_unlock();
9445
9446 info->xdp.ifindex = ifindex;
9447 return 0;
9448}
9449
9450static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog,
9451 struct bpf_prog *old_prog)
9452{
9453 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
9454 enum bpf_xdp_mode mode;
9455 bpf_op_t bpf_op;
9456 int err = 0;
9457
9458 rtnl_lock();
9459
9460 /* link might have been auto-released already, so fail */
9461 if (!xdp_link->dev) {
9462 err = -ENOLINK;
9463 goto out_unlock;
9464 }
9465
9466 if (old_prog && link->prog != old_prog) {
9467 err = -EPERM;
9468 goto out_unlock;
9469 }
9470 old_prog = link->prog;
9471 if (old_prog->type != new_prog->type ||
9472 old_prog->expected_attach_type != new_prog->expected_attach_type) {
9473 err = -EINVAL;
9474 goto out_unlock;
9475 }
9476
9477 if (old_prog == new_prog) {
9478 /* no-op, don't disturb drivers */
9479 bpf_prog_put(prog: new_prog);
9480 goto out_unlock;
9481 }
9482
9483 mode = dev_xdp_mode(dev: xdp_link->dev, flags: xdp_link->flags);
9484 bpf_op = dev_xdp_bpf_op(dev: xdp_link->dev, mode);
9485 err = dev_xdp_install(dev: xdp_link->dev, mode, bpf_op, NULL,
9486 flags: xdp_link->flags, prog: new_prog);
9487 if (err)
9488 goto out_unlock;
9489
9490 old_prog = xchg(&link->prog, new_prog);
9491 bpf_prog_put(prog: old_prog);
9492
9493out_unlock:
9494 rtnl_unlock();
9495 return err;
9496}
9497
9498static const struct bpf_link_ops bpf_xdp_link_lops = {
9499 .release = bpf_xdp_link_release,
9500 .dealloc = bpf_xdp_link_dealloc,
9501 .detach = bpf_xdp_link_detach,
9502 .show_fdinfo = bpf_xdp_link_show_fdinfo,
9503 .fill_link_info = bpf_xdp_link_fill_link_info,
9504 .update_prog = bpf_xdp_link_update,
9505};
9506
9507int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
9508{
9509 struct net *net = current->nsproxy->net_ns;
9510 struct bpf_link_primer link_primer;
9511 struct netlink_ext_ack extack = {};
9512 struct bpf_xdp_link *link;
9513 struct net_device *dev;
9514 int err, fd;
9515
9516 rtnl_lock();
9517 dev = dev_get_by_index(net, attr->link_create.target_ifindex);
9518 if (!dev) {
9519 rtnl_unlock();
9520 return -EINVAL;
9521 }
9522
9523 link = kzalloc(size: sizeof(*link), GFP_USER);
9524 if (!link) {
9525 err = -ENOMEM;
9526 goto unlock;
9527 }
9528
9529 bpf_link_init(link: &link->link, type: BPF_LINK_TYPE_XDP, ops: &bpf_xdp_link_lops, prog);
9530 link->dev = dev;
9531 link->flags = attr->link_create.flags;
9532
9533 err = bpf_link_prime(link: &link->link, primer: &link_primer);
9534 if (err) {
9535 kfree(objp: link);
9536 goto unlock;
9537 }
9538
9539 err = dev_xdp_attach_link(dev, extack: &extack, link);
9540 rtnl_unlock();
9541
9542 if (err) {
9543 link->dev = NULL;
9544 bpf_link_cleanup(primer: &link_primer);
9545 trace_bpf_xdp_link_attach_failed(msg: extack._msg);
9546 goto out_put_dev;
9547 }
9548
9549 fd = bpf_link_settle(primer: &link_primer);
9550 /* link itself doesn't hold dev's refcnt to not complicate shutdown */
9551 dev_put(dev);
9552 return fd;
9553
9554unlock:
9555 rtnl_unlock();
9556
9557out_put_dev:
9558 dev_put(dev);
9559 return err;
9560}
9561
9562/**
9563 * dev_change_xdp_fd - set or clear a bpf program for a device rx path
9564 * @dev: device
9565 * @extack: netlink extended ack
9566 * @fd: new program fd or negative value to clear
9567 * @expected_fd: old program fd that userspace expects to replace or clear
9568 * @flags: xdp-related flags
9569 *
9570 * Set or clear a bpf program for a device
9571 */
9572int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
9573 int fd, int expected_fd, u32 flags)
9574{
9575 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags);
9576 struct bpf_prog *new_prog = NULL, *old_prog = NULL;
9577 int err;
9578
9579 ASSERT_RTNL();
9580
9581 if (fd >= 0) {
9582 new_prog = bpf_prog_get_type_dev(ufd: fd, type: BPF_PROG_TYPE_XDP,
9583 attach_drv: mode != XDP_MODE_SKB);
9584 if (IS_ERR(ptr: new_prog))
9585 return PTR_ERR(ptr: new_prog);
9586 }
9587
9588 if (expected_fd >= 0) {
9589 old_prog = bpf_prog_get_type_dev(ufd: expected_fd, type: BPF_PROG_TYPE_XDP,
9590 attach_drv: mode != XDP_MODE_SKB);
9591 if (IS_ERR(ptr: old_prog)) {
9592 err = PTR_ERR(ptr: old_prog);
9593 old_prog = NULL;
9594 goto err_out;
9595 }
9596 }
9597
9598 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags);
9599
9600err_out:
9601 if (err && new_prog)
9602 bpf_prog_put(prog: new_prog);
9603 if (old_prog)
9604 bpf_prog_put(prog: old_prog);
9605 return err;
9606}
9607
9608/**
9609 * dev_index_reserve() - allocate an ifindex in a namespace
9610 * @net: the applicable net namespace
9611 * @ifindex: requested ifindex, pass %0 to get one allocated
9612 *
9613 * Allocate a ifindex for a new device. Caller must either use the ifindex
9614 * to store the device (via list_netdevice()) or call dev_index_release()
9615 * to give the index up.
9616 *
9617 * Return: a suitable unique value for a new device interface number or -errno.
9618 */
9619static int dev_index_reserve(struct net *net, u32 ifindex)
9620{
9621 int err;
9622
9623 if (ifindex > INT_MAX) {
9624 DEBUG_NET_WARN_ON_ONCE(1);
9625 return -EINVAL;
9626 }
9627
9628 if (!ifindex)
9629 err = xa_alloc_cyclic(xa: &net->dev_by_index, id: &ifindex, NULL,
9630 xa_limit_31b, next: &net->ifindex, GFP_KERNEL);
9631 else
9632 err = xa_insert(xa: &net->dev_by_index, index: ifindex, NULL, GFP_KERNEL);
9633 if (err < 0)
9634 return err;
9635
9636 return ifindex;
9637}
9638
9639static void dev_index_release(struct net *net, int ifindex)
9640{
9641 /* Expect only unused indexes, unlist_netdevice() removes the used */
9642 WARN_ON(xa_erase(&net->dev_by_index, ifindex));
9643}
9644
9645/* Delayed registration/unregisteration */
9646LIST_HEAD(net_todo_list);
9647DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
9648
9649static void net_set_todo(struct net_device *dev)
9650{
9651 list_add_tail(new: &dev->todo_list, head: &net_todo_list);
9652 atomic_inc(v: &dev_net(dev)->dev_unreg_count);
9653}
9654
9655static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
9656 struct net_device *upper, netdev_features_t features)
9657{
9658 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
9659 netdev_features_t feature;
9660 int feature_bit;
9661
9662 for_each_netdev_feature(upper_disables, feature_bit) {
9663 feature = __NETIF_F_BIT(feature_bit);
9664 if (!(upper->wanted_features & feature)
9665 && (features & feature)) {
9666 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
9667 &feature, upper->name);
9668 features &= ~feature;
9669 }
9670 }
9671
9672 return features;
9673}
9674
9675static void netdev_sync_lower_features(struct net_device *upper,
9676 struct net_device *lower, netdev_features_t features)
9677{
9678 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
9679 netdev_features_t feature;
9680 int feature_bit;
9681
9682 for_each_netdev_feature(upper_disables, feature_bit) {
9683 feature = __NETIF_F_BIT(feature_bit);
9684 if (!(features & feature) && (lower->features & feature)) {
9685 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
9686 &feature, lower->name);
9687 lower->wanted_features &= ~feature;
9688 __netdev_update_features(dev: lower);
9689
9690 if (unlikely(lower->features & feature))
9691 netdev_WARN(upper, "failed to disable %pNF on %s!\n",
9692 &feature, lower->name);
9693 else
9694 netdev_features_change(lower);
9695 }
9696 }
9697}
9698
9699static netdev_features_t netdev_fix_features(struct net_device *dev,
9700 netdev_features_t features)
9701{
9702 /* Fix illegal checksum combinations */
9703 if ((features & NETIF_F_HW_CSUM) &&
9704 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
9705 netdev_warn(dev, format: "mixed HW and IP checksum settings.\n");
9706 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
9707 }
9708
9709 /* TSO requires that SG is present as well. */
9710 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
9711 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
9712 features &= ~NETIF_F_ALL_TSO;
9713 }
9714
9715 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
9716 !(features & NETIF_F_IP_CSUM)) {
9717 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
9718 features &= ~NETIF_F_TSO;
9719 features &= ~NETIF_F_TSO_ECN;
9720 }
9721
9722 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
9723 !(features & NETIF_F_IPV6_CSUM)) {
9724 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
9725 features &= ~NETIF_F_TSO6;
9726 }
9727
9728 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */
9729 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO))
9730 features &= ~NETIF_F_TSO_MANGLEID;
9731
9732 /* TSO ECN requires that TSO is present as well. */
9733 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
9734 features &= ~NETIF_F_TSO_ECN;
9735
9736 /* Software GSO depends on SG. */
9737 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
9738 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
9739 features &= ~NETIF_F_GSO;
9740 }
9741
9742 /* GSO partial features require GSO partial be set */
9743 if ((features & dev->gso_partial_features) &&
9744 !(features & NETIF_F_GSO_PARTIAL)) {
9745 netdev_dbg(dev,
9746 "Dropping partially supported GSO features since no GSO partial.\n");
9747 features &= ~dev->gso_partial_features;
9748 }
9749
9750 if (!(features & NETIF_F_RXCSUM)) {
9751 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet
9752 * successfully merged by hardware must also have the
9753 * checksum verified by hardware. If the user does not
9754 * want to enable RXCSUM, logically, we should disable GRO_HW.
9755 */
9756 if (features & NETIF_F_GRO_HW) {
9757 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n");
9758 features &= ~NETIF_F_GRO_HW;
9759 }
9760 }
9761
9762 /* LRO/HW-GRO features cannot be combined with RX-FCS */
9763 if (features & NETIF_F_RXFCS) {
9764 if (features & NETIF_F_LRO) {
9765 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n");
9766 features &= ~NETIF_F_LRO;
9767 }
9768
9769 if (features & NETIF_F_GRO_HW) {
9770 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n");
9771 features &= ~NETIF_F_GRO_HW;
9772 }
9773 }
9774
9775 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) {
9776 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n");
9777 features &= ~NETIF_F_LRO;
9778 }
9779
9780 if (features & NETIF_F_HW_TLS_TX) {
9781 bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) ==
9782 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM);
9783 bool hw_csum = features & NETIF_F_HW_CSUM;
9784
9785 if (!ip_csum && !hw_csum) {
9786 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n");
9787 features &= ~NETIF_F_HW_TLS_TX;
9788 }
9789 }
9790
9791 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) {
9792 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n");
9793 features &= ~NETIF_F_HW_TLS_RX;
9794 }
9795
9796 return features;
9797}
9798
9799int __netdev_update_features(struct net_device *dev)
9800{
9801 struct net_device *upper, *lower;
9802 netdev_features_t features;
9803 struct list_head *iter;
9804 int err = -1;
9805
9806 ASSERT_RTNL();
9807
9808 features = netdev_get_wanted_features(dev);
9809
9810 if (dev->netdev_ops->ndo_fix_features)
9811 features = dev->netdev_ops->ndo_fix_features(dev, features);
9812
9813 /* driver might be less strict about feature dependencies */
9814 features = netdev_fix_features(dev, features);
9815
9816 /* some features can't be enabled if they're off on an upper device */
9817 netdev_for_each_upper_dev_rcu(dev, upper, iter)
9818 features = netdev_sync_upper_features(lower: dev, upper, features);
9819
9820 if (dev->features == features)
9821 goto sync_lower;
9822
9823 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
9824 &dev->features, &features);
9825
9826 if (dev->netdev_ops->ndo_set_features)
9827 err = dev->netdev_ops->ndo_set_features(dev, features);
9828 else
9829 err = 0;
9830
9831 if (unlikely(err < 0)) {
9832 netdev_err(dev,
9833 format: "set_features() failed (%d); wanted %pNF, left %pNF\n",
9834 err, &features, &dev->features);
9835 /* return non-0 since some features might have changed and
9836 * it's better to fire a spurious notification than miss it
9837 */
9838 return -1;
9839 }
9840
9841sync_lower:
9842 /* some features must be disabled on lower devices when disabled
9843 * on an upper device (think: bonding master or bridge)
9844 */
9845 netdev_for_each_lower_dev(dev, lower, iter)
9846 netdev_sync_lower_features(upper: dev, lower, features);
9847
9848 if (!err) {
9849 netdev_features_t diff = features ^ dev->features;
9850
9851 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) {
9852 /* udp_tunnel_{get,drop}_rx_info both need
9853 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the
9854 * device, or they won't do anything.
9855 * Thus we need to update dev->features
9856 * *before* calling udp_tunnel_get_rx_info,
9857 * but *after* calling udp_tunnel_drop_rx_info.
9858 */
9859 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) {
9860 dev->features = features;
9861 udp_tunnel_get_rx_info(dev);
9862 } else {
9863 udp_tunnel_drop_rx_info(dev);
9864 }
9865 }
9866
9867 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) {
9868 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) {
9869 dev->features = features;
9870 err |= vlan_get_rx_ctag_filter_info(dev);
9871 } else {
9872 vlan_drop_rx_ctag_filter_info(dev);
9873 }
9874 }
9875
9876 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) {
9877 if (features & NETIF_F_HW_VLAN_STAG_FILTER) {
9878 dev->features = features;
9879 err |= vlan_get_rx_stag_filter_info(dev);
9880 } else {
9881 vlan_drop_rx_stag_filter_info(dev);
9882 }
9883 }
9884
9885 dev->features = features;
9886 }
9887
9888 return err < 0 ? 0 : 1;
9889}
9890
9891/**
9892 * netdev_update_features - recalculate device features
9893 * @dev: the device to check
9894 *
9895 * Recalculate dev->features set and send notifications if it
9896 * has changed. Should be called after driver or hardware dependent
9897 * conditions might have changed that influence the features.
9898 */
9899void netdev_update_features(struct net_device *dev)
9900{
9901 if (__netdev_update_features(dev))
9902 netdev_features_change(dev);
9903}
9904EXPORT_SYMBOL(netdev_update_features);
9905
9906/**
9907 * netdev_change_features - recalculate device features
9908 * @dev: the device to check
9909 *
9910 * Recalculate dev->features set and send notifications even
9911 * if they have not changed. Should be called instead of
9912 * netdev_update_features() if also dev->vlan_features might
9913 * have changed to allow the changes to be propagated to stacked
9914 * VLAN devices.
9915 */
9916void netdev_change_features(struct net_device *dev)
9917{
9918 __netdev_update_features(dev);
9919 netdev_features_change(dev);
9920}
9921EXPORT_SYMBOL(netdev_change_features);
9922
9923/**
9924 * netif_stacked_transfer_operstate - transfer operstate
9925 * @rootdev: the root or lower level device to transfer state from
9926 * @dev: the device to transfer operstate to
9927 *
9928 * Transfer operational state from root to device. This is normally
9929 * called when a stacking relationship exists between the root
9930 * device and the device(a leaf device).
9931 */
9932void netif_stacked_transfer_operstate(const struct net_device *rootdev,
9933 struct net_device *dev)
9934{
9935 if (rootdev->operstate == IF_OPER_DORMANT)
9936 netif_dormant_on(dev);
9937 else
9938 netif_dormant_off(dev);
9939
9940 if (rootdev->operstate == IF_OPER_TESTING)
9941 netif_testing_on(dev);
9942 else
9943 netif_testing_off(dev);
9944
9945 if (netif_carrier_ok(dev: rootdev))
9946 netif_carrier_on(dev);
9947 else
9948 netif_carrier_off(dev);
9949}
9950EXPORT_SYMBOL(netif_stacked_transfer_operstate);
9951
9952static int netif_alloc_rx_queues(struct net_device *dev)
9953{
9954 unsigned int i, count = dev->num_rx_queues;
9955 struct netdev_rx_queue *rx;
9956 size_t sz = count * sizeof(*rx);
9957 int err = 0;
9958
9959 BUG_ON(count < 1);
9960
9961 rx = kvzalloc(size: sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
9962 if (!rx)
9963 return -ENOMEM;
9964
9965 dev->_rx = rx;
9966
9967 for (i = 0; i < count; i++) {
9968 rx[i].dev = dev;
9969
9970 /* XDP RX-queue setup */
9971 err = xdp_rxq_info_reg(xdp_rxq: &rx[i].xdp_rxq, dev, queue_index: i, napi_id: 0);
9972 if (err < 0)
9973 goto err_rxq_info;
9974 }
9975 return 0;
9976
9977err_rxq_info:
9978 /* Rollback successful reg's and free other resources */
9979 while (i--)
9980 xdp_rxq_info_unreg(xdp_rxq: &rx[i].xdp_rxq);
9981 kvfree(addr: dev->_rx);
9982 dev->_rx = NULL;
9983 return err;
9984}
9985
9986static void netif_free_rx_queues(struct net_device *dev)
9987{
9988 unsigned int i, count = dev->num_rx_queues;
9989
9990 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */
9991 if (!dev->_rx)
9992 return;
9993
9994 for (i = 0; i < count; i++)
9995 xdp_rxq_info_unreg(xdp_rxq: &dev->_rx[i].xdp_rxq);
9996
9997 kvfree(addr: dev->_rx);
9998}
9999
10000static void netdev_init_one_queue(struct net_device *dev,
10001 struct netdev_queue *queue, void *_unused)
10002{
10003 /* Initialize queue lock */
10004 spin_lock_init(&queue->_xmit_lock);
10005 netdev_set_xmit_lockdep_class(lock: &queue->_xmit_lock, dev_type: dev->type);
10006 queue->xmit_lock_owner = -1;
10007 netdev_queue_numa_node_write(q: queue, NUMA_NO_NODE);
10008 queue->dev = dev;
10009#ifdef CONFIG_BQL
10010 dql_init(dql: &queue->dql, HZ);
10011#endif
10012}
10013
10014static void netif_free_tx_queues(struct net_device *dev)
10015{
10016 kvfree(addr: dev->_tx);
10017}
10018
10019static int netif_alloc_netdev_queues(struct net_device *dev)
10020{
10021 unsigned int count = dev->num_tx_queues;
10022 struct netdev_queue *tx;
10023 size_t sz = count * sizeof(*tx);
10024
10025 if (count < 1 || count > 0xffff)
10026 return -EINVAL;
10027
10028 tx = kvzalloc(size: sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
10029 if (!tx)
10030 return -ENOMEM;
10031
10032 dev->_tx = tx;
10033
10034 netdev_for_each_tx_queue(dev, f: netdev_init_one_queue, NULL);
10035 spin_lock_init(&dev->tx_global_lock);
10036
10037 return 0;
10038}
10039
10040void netif_tx_stop_all_queues(struct net_device *dev)
10041{
10042 unsigned int i;
10043
10044 for (i = 0; i < dev->num_tx_queues; i++) {
10045 struct netdev_queue *txq = netdev_get_tx_queue(dev, index: i);
10046
10047 netif_tx_stop_queue(dev_queue: txq);
10048 }
10049}
10050EXPORT_SYMBOL(netif_tx_stop_all_queues);
10051
10052/**
10053 * register_netdevice() - register a network device
10054 * @dev: device to register
10055 *
10056 * Take a prepared network device structure and make it externally accessible.
10057 * A %NETDEV_REGISTER message is sent to the netdev notifier chain.
10058 * Callers must hold the rtnl lock - you may want register_netdev()
10059 * instead of this.
10060 */
10061int register_netdevice(struct net_device *dev)
10062{
10063 int ret;
10064 struct net *net = dev_net(dev);
10065
10066 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE <
10067 NETDEV_FEATURE_COUNT);
10068 BUG_ON(dev_boot_phase);
10069 ASSERT_RTNL();
10070
10071 might_sleep();
10072
10073 /* When net_device's are persistent, this will be fatal. */
10074 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
10075 BUG_ON(!net);
10076
10077 ret = ethtool_check_ops(ops: dev->ethtool_ops);
10078 if (ret)
10079 return ret;
10080
10081 spin_lock_init(&dev->addr_list_lock);
10082 netdev_set_addr_lockdep_class(dev);
10083
10084 ret = dev_get_valid_name(net, dev, name: dev->name);
10085 if (ret < 0)
10086 goto out;
10087
10088 ret = -ENOMEM;
10089 dev->name_node = netdev_name_node_head_alloc(dev);
10090 if (!dev->name_node)
10091 goto out;
10092
10093 /* Init, if this function is available */
10094 if (dev->netdev_ops->ndo_init) {
10095 ret = dev->netdev_ops->ndo_init(dev);
10096 if (ret) {
10097 if (ret > 0)
10098 ret = -EIO;
10099 goto err_free_name;
10100 }
10101 }
10102
10103 if (((dev->hw_features | dev->features) &
10104 NETIF_F_HW_VLAN_CTAG_FILTER) &&
10105 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
10106 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
10107 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
10108 ret = -EINVAL;
10109 goto err_uninit;
10110 }
10111
10112 ret = dev_index_reserve(net, ifindex: dev->ifindex);
10113 if (ret < 0)
10114 goto err_uninit;
10115 dev->ifindex = ret;
10116
10117 /* Transfer changeable features to wanted_features and enable
10118 * software offloads (GSO and GRO).
10119 */
10120 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF);
10121 dev->features |= NETIF_F_SOFT_FEATURES;
10122
10123 if (dev->udp_tunnel_nic_info) {
10124 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT;
10125 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT;
10126 }
10127
10128 dev->wanted_features = dev->features & dev->hw_features;
10129
10130 if (!(dev->flags & IFF_LOOPBACK))
10131 dev->hw_features |= NETIF_F_NOCACHE_COPY;
10132
10133 /* If IPv4 TCP segmentation offload is supported we should also
10134 * allow the device to enable segmenting the frame with the option
10135 * of ignoring a static IP ID value. This doesn't enable the
10136 * feature itself but allows the user to enable it later.
10137 */
10138 if (dev->hw_features & NETIF_F_TSO)
10139 dev->hw_features |= NETIF_F_TSO_MANGLEID;
10140 if (dev->vlan_features & NETIF_F_TSO)
10141 dev->vlan_features |= NETIF_F_TSO_MANGLEID;
10142 if (dev->mpls_features & NETIF_F_TSO)
10143 dev->mpls_features |= NETIF_F_TSO_MANGLEID;
10144 if (dev->hw_enc_features & NETIF_F_TSO)
10145 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;
10146
10147 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
10148 */
10149 dev->vlan_features |= NETIF_F_HIGHDMA;
10150
10151 /* Make NETIF_F_SG inheritable to tunnel devices.
10152 */
10153 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
10154
10155 /* Make NETIF_F_SG inheritable to MPLS.
10156 */
10157 dev->mpls_features |= NETIF_F_SG;
10158
10159 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
10160 ret = notifier_to_errno(ret);
10161 if (ret)
10162 goto err_ifindex_release;
10163
10164 ret = netdev_register_kobject(dev);
10165 write_lock(&dev_base_lock);
10166 dev->reg_state = ret ? NETREG_UNREGISTERED : NETREG_REGISTERED;
10167 write_unlock(&dev_base_lock);
10168 if (ret)
10169 goto err_uninit_notify;
10170
10171 __netdev_update_features(dev);
10172
10173 /*
10174 * Default initial state at registry is that the
10175 * device is present.
10176 */
10177
10178 set_bit(nr: __LINK_STATE_PRESENT, addr: &dev->state);
10179
10180 linkwatch_init_dev(dev);
10181
10182 dev_init_scheduler(dev);
10183
10184 netdev_hold(dev, tracker: &dev->dev_registered_tracker, GFP_KERNEL);
10185 list_netdevice(dev);
10186
10187 add_device_randomness(buf: dev->dev_addr, len: dev->addr_len);
10188
10189 /* If the device has permanent device address, driver should
10190 * set dev_addr and also addr_assign_type should be set to
10191 * NET_ADDR_PERM (default value).
10192 */
10193 if (dev->addr_assign_type == NET_ADDR_PERM)
10194 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
10195
10196 /* Notify protocols, that a new device appeared. */
10197 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
10198 ret = notifier_to_errno(ret);
10199 if (ret) {
10200 /* Expect explicit free_netdev() on failure */
10201 dev->needs_free_netdev = false;
10202 unregister_netdevice_queue(dev, NULL);
10203 goto out;
10204 }
10205 /*
10206 * Prevent userspace races by waiting until the network
10207 * device is fully setup before sending notifications.
10208 */
10209 if (!dev->rtnl_link_ops ||
10210 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
10211 rtmsg_ifinfo(RTM_NEWLINK, dev, change: ~0U, GFP_KERNEL, portid: 0, NULL);
10212
10213out:
10214 return ret;
10215
10216err_uninit_notify:
10217 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev);
10218err_ifindex_release:
10219 dev_index_release(net, ifindex: dev->ifindex);
10220err_uninit:
10221 if (dev->netdev_ops->ndo_uninit)
10222 dev->netdev_ops->ndo_uninit(dev);
10223 if (dev->priv_destructor)
10224 dev->priv_destructor(dev);
10225err_free_name:
10226 netdev_name_node_free(name_node: dev->name_node);
10227 goto out;
10228}
10229EXPORT_SYMBOL(register_netdevice);
10230
10231/**
10232 * init_dummy_netdev - init a dummy network device for NAPI
10233 * @dev: device to init
10234 *
10235 * This takes a network device structure and initialize the minimum
10236 * amount of fields so it can be used to schedule NAPI polls without
10237 * registering a full blown interface. This is to be used by drivers
10238 * that need to tie several hardware interfaces to a single NAPI
10239 * poll scheduler due to HW limitations.
10240 */
10241int init_dummy_netdev(struct net_device *dev)
10242{
10243 /* Clear everything. Note we don't initialize spinlocks
10244 * are they aren't supposed to be taken by any of the
10245 * NAPI code and this dummy netdev is supposed to be
10246 * only ever used for NAPI polls
10247 */
10248 memset(dev, 0, sizeof(struct net_device));
10249
10250 /* make sure we BUG if trying to hit standard
10251 * register/unregister code path
10252 */
10253 dev->reg_state = NETREG_DUMMY;
10254
10255 /* NAPI wants this */
10256 INIT_LIST_HEAD(list: &dev->napi_list);
10257
10258 /* a dummy interface is started by default */
10259 set_bit(nr: __LINK_STATE_PRESENT, addr: &dev->state);
10260 set_bit(nr: __LINK_STATE_START, addr: &dev->state);
10261
10262 /* napi_busy_loop stats accounting wants this */
10263 dev_net_set(dev, net: &init_net);
10264
10265 /* Note : We dont allocate pcpu_refcnt for dummy devices,
10266 * because users of this 'device' dont need to change
10267 * its refcount.
10268 */
10269
10270 return 0;
10271}
10272EXPORT_SYMBOL_GPL(init_dummy_netdev);
10273
10274
10275/**
10276 * register_netdev - register a network device
10277 * @dev: device to register
10278 *
10279 * Take a completed network device structure and add it to the kernel
10280 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
10281 * chain. 0 is returned on success. A negative errno code is returned
10282 * on a failure to set up the device, or if the name is a duplicate.
10283 *
10284 * This is a wrapper around register_netdevice that takes the rtnl semaphore
10285 * and expands the device name if you passed a format string to
10286 * alloc_netdev.
10287 */
10288int register_netdev(struct net_device *dev)
10289{
10290 int err;
10291
10292 if (rtnl_lock_killable())
10293 return -EINTR;
10294 err = register_netdevice(dev);
10295 rtnl_unlock();
10296 return err;
10297}
10298EXPORT_SYMBOL(register_netdev);
10299
10300int netdev_refcnt_read(const struct net_device *dev)
10301{
10302#ifdef CONFIG_PCPU_DEV_REFCNT
10303 int i, refcnt = 0;
10304
10305 for_each_possible_cpu(i)
10306 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
10307 return refcnt;
10308#else
10309 return refcount_read(&dev->dev_refcnt);
10310#endif
10311}
10312EXPORT_SYMBOL(netdev_refcnt_read);
10313
10314int netdev_unregister_timeout_secs __read_mostly = 10;
10315
10316#define WAIT_REFS_MIN_MSECS 1
10317#define WAIT_REFS_MAX_MSECS 250
10318/**
10319 * netdev_wait_allrefs_any - wait until all references are gone.
10320 * @list: list of net_devices to wait on
10321 *
10322 * This is called when unregistering network devices.
10323 *
10324 * Any protocol or device that holds a reference should register
10325 * for netdevice notification, and cleanup and put back the
10326 * reference if they receive an UNREGISTER event.
10327 * We can get stuck here if buggy protocols don't correctly
10328 * call dev_put.
10329 */
10330static struct net_device *netdev_wait_allrefs_any(struct list_head *list)
10331{
10332 unsigned long rebroadcast_time, warning_time;
10333 struct net_device *dev;
10334 int wait = 0;
10335
10336 rebroadcast_time = warning_time = jiffies;
10337
10338 list_for_each_entry(dev, list, todo_list)
10339 if (netdev_refcnt_read(dev) == 1)
10340 return dev;
10341
10342 while (true) {
10343 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
10344 rtnl_lock();
10345
10346 /* Rebroadcast unregister notification */
10347 list_for_each_entry(dev, list, todo_list)
10348 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
10349
10350 __rtnl_unlock();
10351 rcu_barrier();
10352 rtnl_lock();
10353
10354 list_for_each_entry(dev, list, todo_list)
10355 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
10356 &dev->state)) {
10357 /* We must not have linkwatch events
10358 * pending on unregister. If this
10359 * happens, we simply run the queue
10360 * unscheduled, resulting in a noop
10361 * for this device.
10362 */
10363 linkwatch_run_queue();
10364 break;
10365 }
10366
10367 __rtnl_unlock();
10368
10369 rebroadcast_time = jiffies;
10370 }
10371
10372 if (!wait) {
10373 rcu_barrier();
10374 wait = WAIT_REFS_MIN_MSECS;
10375 } else {
10376 msleep(msecs: wait);
10377 wait = min(wait << 1, WAIT_REFS_MAX_MSECS);
10378 }
10379
10380 list_for_each_entry(dev, list, todo_list)
10381 if (netdev_refcnt_read(dev) == 1)
10382 return dev;
10383
10384 if (time_after(jiffies, warning_time +
10385 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) {
10386 list_for_each_entry(dev, list, todo_list) {
10387 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
10388 dev->name, netdev_refcnt_read(dev));
10389 ref_tracker_dir_print(dir: &dev->refcnt_tracker, display_limit: 10);
10390 }
10391
10392 warning_time = jiffies;
10393 }
10394 }
10395}
10396
10397/* The sequence is:
10398 *
10399 * rtnl_lock();
10400 * ...
10401 * register_netdevice(x1);
10402 * register_netdevice(x2);
10403 * ...
10404 * unregister_netdevice(y1);
10405 * unregister_netdevice(y2);
10406 * ...
10407 * rtnl_unlock();
10408 * free_netdev(y1);
10409 * free_netdev(y2);
10410 *
10411 * We are invoked by rtnl_unlock().
10412 * This allows us to deal with problems:
10413 * 1) We can delete sysfs objects which invoke hotplug
10414 * without deadlocking with linkwatch via keventd.
10415 * 2) Since we run with the RTNL semaphore not held, we can sleep
10416 * safely in order to wait for the netdev refcnt to drop to zero.
10417 *
10418 * We must not return until all unregister events added during
10419 * the interval the lock was held have been completed.
10420 */
10421void netdev_run_todo(void)
10422{
10423 struct net_device *dev, *tmp;
10424 struct list_head list;
10425#ifdef CONFIG_LOCKDEP
10426 struct list_head unlink_list;
10427
10428 list_replace_init(old: &net_unlink_list, new: &unlink_list);
10429
10430 while (!list_empty(head: &unlink_list)) {
10431 struct net_device *dev = list_first_entry(&unlink_list,
10432 struct net_device,
10433 unlink_list);
10434 list_del_init(entry: &dev->unlink_list);
10435 dev->nested_level = dev->lower_level - 1;
10436 }
10437#endif
10438
10439 /* Snapshot list, allow later requests */
10440 list_replace_init(old: &net_todo_list, new: &list);
10441
10442 __rtnl_unlock();
10443
10444 /* Wait for rcu callbacks to finish before next phase */
10445 if (!list_empty(head: &list))
10446 rcu_barrier();
10447
10448 list_for_each_entry_safe(dev, tmp, &list, todo_list) {
10449 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
10450 netdev_WARN(dev, "run_todo but not unregistering\n");
10451 list_del(entry: &dev->todo_list);
10452 continue;
10453 }
10454
10455 write_lock(&dev_base_lock);
10456 dev->reg_state = NETREG_UNREGISTERED;
10457 write_unlock(&dev_base_lock);
10458 linkwatch_forget_dev(dev);
10459 }
10460
10461 while (!list_empty(head: &list)) {
10462 dev = netdev_wait_allrefs_any(list: &list);
10463 list_del(entry: &dev->todo_list);
10464
10465 /* paranoia */
10466 BUG_ON(netdev_refcnt_read(dev) != 1);
10467 BUG_ON(!list_empty(&dev->ptype_all));
10468 BUG_ON(!list_empty(&dev->ptype_specific));
10469 WARN_ON(rcu_access_pointer(dev->ip_ptr));
10470 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
10471
10472 if (dev->priv_destructor)
10473 dev->priv_destructor(dev);
10474 if (dev->needs_free_netdev)
10475 free_netdev(dev);
10476
10477 if (atomic_dec_and_test(v: &dev_net(dev)->dev_unreg_count))
10478 wake_up(&netdev_unregistering_wq);
10479
10480 /* Free network device */
10481 kobject_put(kobj: &dev->dev.kobj);
10482 }
10483}
10484
10485/* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
10486 * all the same fields in the same order as net_device_stats, with only
10487 * the type differing, but rtnl_link_stats64 may have additional fields
10488 * at the end for newer counters.
10489 */
10490void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
10491 const struct net_device_stats *netdev_stats)
10492{
10493 size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t);
10494 const atomic_long_t *src = (atomic_long_t *)netdev_stats;
10495 u64 *dst = (u64 *)stats64;
10496
10497 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
10498 for (i = 0; i < n; i++)
10499 dst[i] = (unsigned long)atomic_long_read(v: &src[i]);
10500 /* zero out counters that only exist in rtnl_link_stats64 */
10501 memset((char *)stats64 + n * sizeof(u64), 0,
10502 sizeof(*stats64) - n * sizeof(u64));
10503}
10504EXPORT_SYMBOL(netdev_stats_to_stats64);
10505
10506static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc(
10507 struct net_device *dev)
10508{
10509 struct net_device_core_stats __percpu *p;
10510
10511 p = alloc_percpu_gfp(struct net_device_core_stats,
10512 GFP_ATOMIC | __GFP_NOWARN);
10513
10514 if (p && cmpxchg(&dev->core_stats, NULL, p))
10515 free_percpu(pdata: p);
10516
10517 /* This READ_ONCE() pairs with the cmpxchg() above */
10518 return READ_ONCE(dev->core_stats);
10519}
10520
10521noinline void netdev_core_stats_inc(struct net_device *dev, u32 offset)
10522{
10523 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */
10524 struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats);
10525 unsigned long __percpu *field;
10526
10527 if (unlikely(!p)) {
10528 p = netdev_core_stats_alloc(dev);
10529 if (!p)
10530 return;
10531 }
10532
10533 field = (__force unsigned long __percpu *)((__force void *)p + offset);
10534 this_cpu_inc(*field);
10535}
10536EXPORT_SYMBOL_GPL(netdev_core_stats_inc);
10537
10538/**
10539 * dev_get_stats - get network device statistics
10540 * @dev: device to get statistics from
10541 * @storage: place to store stats
10542 *
10543 * Get network statistics from device. Return @storage.
10544 * The device driver may provide its own method by setting
10545 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
10546 * otherwise the internal statistics structure is used.
10547 */
10548struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
10549 struct rtnl_link_stats64 *storage)
10550{
10551 const struct net_device_ops *ops = dev->netdev_ops;
10552 const struct net_device_core_stats __percpu *p;
10553
10554 if (ops->ndo_get_stats64) {
10555 memset(storage, 0, sizeof(*storage));
10556 ops->ndo_get_stats64(dev, storage);
10557 } else if (ops->ndo_get_stats) {
10558 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
10559 } else {
10560 netdev_stats_to_stats64(storage, &dev->stats);
10561 }
10562
10563 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */
10564 p = READ_ONCE(dev->core_stats);
10565 if (p) {
10566 const struct net_device_core_stats *core_stats;
10567 int i;
10568
10569 for_each_possible_cpu(i) {
10570 core_stats = per_cpu_ptr(p, i);
10571 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped);
10572 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped);
10573 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler);
10574 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped);
10575 }
10576 }
10577 return storage;
10578}
10579EXPORT_SYMBOL(dev_get_stats);
10580
10581/**
10582 * dev_fetch_sw_netstats - get per-cpu network device statistics
10583 * @s: place to store stats
10584 * @netstats: per-cpu network stats to read from
10585 *
10586 * Read per-cpu network statistics and populate the related fields in @s.
10587 */
10588void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s,
10589 const struct pcpu_sw_netstats __percpu *netstats)
10590{
10591 int cpu;
10592
10593 for_each_possible_cpu(cpu) {
10594 u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
10595 const struct pcpu_sw_netstats *stats;
10596 unsigned int start;
10597
10598 stats = per_cpu_ptr(netstats, cpu);
10599 do {
10600 start = u64_stats_fetch_begin(syncp: &stats->syncp);
10601 rx_packets = u64_stats_read(p: &stats->rx_packets);
10602 rx_bytes = u64_stats_read(p: &stats->rx_bytes);
10603 tx_packets = u64_stats_read(p: &stats->tx_packets);
10604 tx_bytes = u64_stats_read(p: &stats->tx_bytes);
10605 } while (u64_stats_fetch_retry(syncp: &stats->syncp, start));
10606
10607 s->rx_packets += rx_packets;
10608 s->rx_bytes += rx_bytes;
10609 s->tx_packets += tx_packets;
10610 s->tx_bytes += tx_bytes;
10611 }
10612}
10613EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats);
10614
10615/**
10616 * dev_get_tstats64 - ndo_get_stats64 implementation
10617 * @dev: device to get statistics from
10618 * @s: place to store stats
10619 *
10620 * Populate @s from dev->stats and dev->tstats. Can be used as
10621 * ndo_get_stats64() callback.
10622 */
10623void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s)
10624{
10625 netdev_stats_to_stats64(s, &dev->stats);
10626 dev_fetch_sw_netstats(s, dev->tstats);
10627}
10628EXPORT_SYMBOL_GPL(dev_get_tstats64);
10629
10630struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
10631{
10632 struct netdev_queue *queue = dev_ingress_queue(dev);
10633
10634#ifdef CONFIG_NET_CLS_ACT
10635 if (queue)
10636 return queue;
10637 queue = kzalloc(size: sizeof(*queue), GFP_KERNEL);
10638 if (!queue)
10639 return NULL;
10640 netdev_init_one_queue(dev, queue, NULL);
10641 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
10642 RCU_INIT_POINTER(queue->qdisc_sleeping, &noop_qdisc);
10643 rcu_assign_pointer(dev->ingress_queue, queue);
10644#endif
10645 return queue;
10646}
10647
10648static const struct ethtool_ops default_ethtool_ops;
10649
10650void netdev_set_default_ethtool_ops(struct net_device *dev,
10651 const struct ethtool_ops *ops)
10652{
10653 if (dev->ethtool_ops == &default_ethtool_ops)
10654 dev->ethtool_ops = ops;
10655}
10656EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
10657
10658/**
10659 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default
10660 * @dev: netdev to enable the IRQ coalescing on
10661 *
10662 * Sets a conservative default for SW IRQ coalescing. Users can use
10663 * sysfs attributes to override the default values.
10664 */
10665void netdev_sw_irq_coalesce_default_on(struct net_device *dev)
10666{
10667 WARN_ON(dev->reg_state == NETREG_REGISTERED);
10668
10669 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
10670 dev->gro_flush_timeout = 20000;
10671 dev->napi_defer_hard_irqs = 1;
10672 }
10673}
10674EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on);
10675
10676void netdev_freemem(struct net_device *dev)
10677{
10678 char *addr = (char *)dev - dev->padded;
10679
10680 kvfree(addr);
10681}
10682
10683/**
10684 * alloc_netdev_mqs - allocate network device
10685 * @sizeof_priv: size of private data to allocate space for
10686 * @name: device name format string
10687 * @name_assign_type: origin of device name
10688 * @setup: callback to initialize device
10689 * @txqs: the number of TX subqueues to allocate
10690 * @rxqs: the number of RX subqueues to allocate
10691 *
10692 * Allocates a struct net_device with private data area for driver use
10693 * and performs basic initialization. Also allocates subqueue structs
10694 * for each queue on the device.
10695 */
10696struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
10697 unsigned char name_assign_type,
10698 void (*setup)(struct net_device *),
10699 unsigned int txqs, unsigned int rxqs)
10700{
10701 struct net_device *dev;
10702 unsigned int alloc_size;
10703 struct net_device *p;
10704
10705 BUG_ON(strlen(name) >= sizeof(dev->name));
10706
10707 if (txqs < 1) {
10708 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
10709 return NULL;
10710 }
10711
10712 if (rxqs < 1) {
10713 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
10714 return NULL;
10715 }
10716
10717 alloc_size = sizeof(struct net_device);
10718 if (sizeof_priv) {
10719 /* ensure 32-byte alignment of private area */
10720 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
10721 alloc_size += sizeof_priv;
10722 }
10723 /* ensure 32-byte alignment of whole construct */
10724 alloc_size += NETDEV_ALIGN - 1;
10725
10726 p = kvzalloc(size: alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
10727 if (!p)
10728 return NULL;
10729
10730 dev = PTR_ALIGN(p, NETDEV_ALIGN);
10731 dev->padded = (char *)dev - (char *)p;
10732
10733 ref_tracker_dir_init(dir: &dev->refcnt_tracker, quarantine_count: 128, name);
10734#ifdef CONFIG_PCPU_DEV_REFCNT
10735 dev->pcpu_refcnt = alloc_percpu(int);
10736 if (!dev->pcpu_refcnt)
10737 goto free_dev;
10738 __dev_hold(dev);
10739#else
10740 refcount_set(&dev->dev_refcnt, 1);
10741#endif
10742
10743 if (dev_addr_init(dev))
10744 goto free_pcpu;
10745
10746 dev_mc_init(dev);
10747 dev_uc_init(dev);
10748
10749 dev_net_set(dev, net: &init_net);
10750
10751 dev->gso_max_size = GSO_LEGACY_MAX_SIZE;
10752 dev->xdp_zc_max_segs = 1;
10753 dev->gso_max_segs = GSO_MAX_SEGS;
10754 dev->gro_max_size = GRO_LEGACY_MAX_SIZE;
10755 dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE;
10756 dev->gro_ipv4_max_size = GRO_LEGACY_MAX_SIZE;
10757 dev->tso_max_size = TSO_LEGACY_MAX_SIZE;
10758 dev->tso_max_segs = TSO_MAX_SEGS;
10759 dev->upper_level = 1;
10760 dev->lower_level = 1;
10761#ifdef CONFIG_LOCKDEP
10762 dev->nested_level = 0;
10763 INIT_LIST_HEAD(list: &dev->unlink_list);
10764#endif
10765
10766 INIT_LIST_HEAD(list: &dev->napi_list);
10767 INIT_LIST_HEAD(list: &dev->unreg_list);
10768 INIT_LIST_HEAD(list: &dev->close_list);
10769 INIT_LIST_HEAD(list: &dev->link_watch_list);
10770 INIT_LIST_HEAD(list: &dev->adj_list.upper);
10771 INIT_LIST_HEAD(list: &dev->adj_list.lower);
10772 INIT_LIST_HEAD(list: &dev->ptype_all);
10773 INIT_LIST_HEAD(list: &dev->ptype_specific);
10774 INIT_LIST_HEAD(list: &dev->net_notifier_list);
10775#ifdef CONFIG_NET_SCHED
10776 hash_init(dev->qdisc_hash);
10777#endif
10778 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
10779 setup(dev);
10780
10781 if (!dev->tx_queue_len) {
10782 dev->priv_flags |= IFF_NO_QUEUE;
10783 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
10784 }
10785
10786 dev->num_tx_queues = txqs;
10787 dev->real_num_tx_queues = txqs;
10788 if (netif_alloc_netdev_queues(dev))
10789 goto free_all;
10790
10791 dev->num_rx_queues = rxqs;
10792 dev->real_num_rx_queues = rxqs;
10793 if (netif_alloc_rx_queues(dev))
10794 goto free_all;
10795
10796 strcpy(p: dev->name, q: name);
10797 dev->name_assign_type = name_assign_type;
10798 dev->group = INIT_NETDEV_GROUP;
10799 if (!dev->ethtool_ops)
10800 dev->ethtool_ops = &default_ethtool_ops;
10801
10802 nf_hook_netdev_init(dev);
10803
10804 return dev;
10805
10806free_all:
10807 free_netdev(dev);
10808 return NULL;
10809
10810free_pcpu:
10811#ifdef CONFIG_PCPU_DEV_REFCNT
10812 free_percpu(pdata: dev->pcpu_refcnt);
10813free_dev:
10814#endif
10815 netdev_freemem(dev);
10816 return NULL;
10817}
10818EXPORT_SYMBOL(alloc_netdev_mqs);
10819
10820/**
10821 * free_netdev - free network device
10822 * @dev: device
10823 *
10824 * This function does the last stage of destroying an allocated device
10825 * interface. The reference to the device object is released. If this
10826 * is the last reference then it will be freed.Must be called in process
10827 * context.
10828 */
10829void free_netdev(struct net_device *dev)
10830{
10831 struct napi_struct *p, *n;
10832
10833 might_sleep();
10834
10835 /* When called immediately after register_netdevice() failed the unwind
10836 * handling may still be dismantling the device. Handle that case by
10837 * deferring the free.
10838 */
10839 if (dev->reg_state == NETREG_UNREGISTERING) {
10840 ASSERT_RTNL();
10841 dev->needs_free_netdev = true;
10842 return;
10843 }
10844
10845 netif_free_tx_queues(dev);
10846 netif_free_rx_queues(dev);
10847
10848 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
10849
10850 /* Flush device addresses */
10851 dev_addr_flush(dev);
10852
10853 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
10854 netif_napi_del(napi: p);
10855
10856 ref_tracker_dir_exit(dir: &dev->refcnt_tracker);
10857#ifdef CONFIG_PCPU_DEV_REFCNT
10858 free_percpu(pdata: dev->pcpu_refcnt);
10859 dev->pcpu_refcnt = NULL;
10860#endif
10861 free_percpu(pdata: dev->core_stats);
10862 dev->core_stats = NULL;
10863 free_percpu(pdata: dev->xdp_bulkq);
10864 dev->xdp_bulkq = NULL;
10865
10866 /* Compatibility with error handling in drivers */
10867 if (dev->reg_state == NETREG_UNINITIALIZED) {
10868 netdev_freemem(dev);
10869 return;
10870 }
10871
10872 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
10873 dev->reg_state = NETREG_RELEASED;
10874
10875 /* will free via device release */
10876 put_device(dev: &dev->dev);
10877}
10878EXPORT_SYMBOL(free_netdev);
10879
10880/**
10881 * synchronize_net - Synchronize with packet receive processing
10882 *
10883 * Wait for packets currently being received to be done.
10884 * Does not block later packets from starting.
10885 */
10886void synchronize_net(void)
10887{
10888 might_sleep();
10889 if (rtnl_is_locked())
10890 synchronize_rcu_expedited();
10891 else
10892 synchronize_rcu();
10893}
10894EXPORT_SYMBOL(synchronize_net);
10895
10896/**
10897 * unregister_netdevice_queue - remove device from the kernel
10898 * @dev: device
10899 * @head: list
10900 *
10901 * This function shuts down a device interface and removes it
10902 * from the kernel tables.
10903 * If head not NULL, device is queued to be unregistered later.
10904 *
10905 * Callers must hold the rtnl semaphore. You may want
10906 * unregister_netdev() instead of this.
10907 */
10908
10909void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
10910{
10911 ASSERT_RTNL();
10912
10913 if (head) {
10914 list_move_tail(list: &dev->unreg_list, head);
10915 } else {
10916 LIST_HEAD(single);
10917
10918 list_add(new: &dev->unreg_list, head: &single);
10919 unregister_netdevice_many(head: &single);
10920 }
10921}
10922EXPORT_SYMBOL(unregister_netdevice_queue);
10923
10924void unregister_netdevice_many_notify(struct list_head *head,
10925 u32 portid, const struct nlmsghdr *nlh)
10926{
10927 struct net_device *dev, *tmp;
10928 LIST_HEAD(close_head);
10929
10930 BUG_ON(dev_boot_phase);
10931 ASSERT_RTNL();
10932
10933 if (list_empty(head))
10934 return;
10935
10936 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
10937 /* Some devices call without registering
10938 * for initialization unwind. Remove those
10939 * devices and proceed with the remaining.
10940 */
10941 if (dev->reg_state == NETREG_UNINITIALIZED) {
10942 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
10943 dev->name, dev);
10944
10945 WARN_ON(1);
10946 list_del(entry: &dev->unreg_list);
10947 continue;
10948 }
10949 dev->dismantle = true;
10950 BUG_ON(dev->reg_state != NETREG_REGISTERED);
10951 }
10952
10953 /* If device is running, close it first. */
10954 list_for_each_entry(dev, head, unreg_list)
10955 list_add_tail(new: &dev->close_list, head: &close_head);
10956 dev_close_many(&close_head, true);
10957
10958 list_for_each_entry(dev, head, unreg_list) {
10959 /* And unlink it from device chain. */
10960 write_lock(&dev_base_lock);
10961 unlist_netdevice(dev, lock: false);
10962 dev->reg_state = NETREG_UNREGISTERING;
10963 write_unlock(&dev_base_lock);
10964 }
10965 flush_all_backlogs();
10966
10967 synchronize_net();
10968
10969 list_for_each_entry(dev, head, unreg_list) {
10970 struct sk_buff *skb = NULL;
10971
10972 /* Shutdown queueing discipline. */
10973 dev_shutdown(dev);
10974 dev_tcx_uninstall(dev);
10975 dev_xdp_uninstall(dev);
10976 bpf_dev_bound_netdev_unregister(dev);
10977
10978 netdev_offload_xstats_disable_all(dev);
10979
10980 /* Notify protocols, that we are about to destroy
10981 * this device. They should clean all the things.
10982 */
10983 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
10984
10985 if (!dev->rtnl_link_ops ||
10986 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
10987 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, change: ~0U, event: 0,
10988 GFP_KERNEL, NULL, new_ifindex: 0,
10989 portid, nlh);
10990
10991 /*
10992 * Flush the unicast and multicast chains
10993 */
10994 dev_uc_flush(dev);
10995 dev_mc_flush(dev);
10996
10997 netdev_name_node_alt_flush(dev);
10998 netdev_name_node_free(name_node: dev->name_node);
10999
11000 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev);
11001
11002 if (dev->netdev_ops->ndo_uninit)
11003 dev->netdev_ops->ndo_uninit(dev);
11004
11005 if (skb)
11006 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh);
11007
11008 /* Notifier chain MUST detach us all upper devices. */
11009 WARN_ON(netdev_has_any_upper_dev(dev));
11010 WARN_ON(netdev_has_any_lower_dev(dev));
11011
11012 /* Remove entries from kobject tree */
11013 netdev_unregister_kobject(dev);
11014#ifdef CONFIG_XPS
11015 /* Remove XPS queueing entries */
11016 netif_reset_xps_queues_gt(dev, index: 0);
11017#endif
11018 }
11019
11020 synchronize_net();
11021
11022 list_for_each_entry(dev, head, unreg_list) {
11023 netdev_put(dev, tracker: &dev->dev_registered_tracker);
11024 net_set_todo(dev);
11025 }
11026
11027 list_del(entry: head);
11028}
11029
11030/**
11031 * unregister_netdevice_many - unregister many devices
11032 * @head: list of devices
11033 *
11034 * Note: As most callers use a stack allocated list_head,
11035 * we force a list_del() to make sure stack wont be corrupted later.
11036 */
11037void unregister_netdevice_many(struct list_head *head)
11038{
11039 unregister_netdevice_many_notify(head, portid: 0, NULL);
11040}
11041EXPORT_SYMBOL(unregister_netdevice_many);
11042
11043/**
11044 * unregister_netdev - remove device from the kernel
11045 * @dev: device
11046 *
11047 * This function shuts down a device interface and removes it
11048 * from the kernel tables.
11049 *
11050 * This is just a wrapper for unregister_netdevice that takes
11051 * the rtnl semaphore. In general you want to use this and not
11052 * unregister_netdevice.
11053 */
11054void unregister_netdev(struct net_device *dev)
11055{
11056 rtnl_lock();
11057 unregister_netdevice(dev);
11058 rtnl_unlock();
11059}
11060EXPORT_SYMBOL(unregister_netdev);
11061
11062/**
11063 * __dev_change_net_namespace - move device to different nethost namespace
11064 * @dev: device
11065 * @net: network namespace
11066 * @pat: If not NULL name pattern to try if the current device name
11067 * is already taken in the destination network namespace.
11068 * @new_ifindex: If not zero, specifies device index in the target
11069 * namespace.
11070 *
11071 * This function shuts down a device interface and moves it
11072 * to a new network namespace. On success 0 is returned, on
11073 * a failure a netagive errno code is returned.
11074 *
11075 * Callers must hold the rtnl semaphore.
11076 */
11077
11078int __dev_change_net_namespace(struct net_device *dev, struct net *net,
11079 const char *pat, int new_ifindex)
11080{
11081 struct netdev_name_node *name_node;
11082 struct net *net_old = dev_net(dev);
11083 char new_name[IFNAMSIZ] = {};
11084 int err, new_nsid;
11085
11086 ASSERT_RTNL();
11087
11088 /* Don't allow namespace local devices to be moved. */
11089 err = -EINVAL;
11090 if (dev->features & NETIF_F_NETNS_LOCAL)
11091 goto out;
11092
11093 /* Ensure the device has been registrered */
11094 if (dev->reg_state != NETREG_REGISTERED)
11095 goto out;
11096
11097 /* Get out if there is nothing todo */
11098 err = 0;
11099 if (net_eq(net1: net_old, net2: net))
11100 goto out;
11101
11102 /* Pick the destination device name, and ensure
11103 * we can use it in the destination network namespace.
11104 */
11105 err = -EEXIST;
11106 if (netdev_name_in_use(net, dev->name)) {
11107 /* We get here if we can't use the current device name */
11108 if (!pat)
11109 goto out;
11110 err = dev_prep_valid_name(net, dev, want_name: pat, out_name: new_name, EEXIST);
11111 if (err < 0)
11112 goto out;
11113 }
11114 /* Check that none of the altnames conflicts. */
11115 err = -EEXIST;
11116 netdev_for_each_altname(dev, name_node)
11117 if (netdev_name_in_use(net, name_node->name))
11118 goto out;
11119
11120 /* Check that new_ifindex isn't used yet. */
11121 if (new_ifindex) {
11122 err = dev_index_reserve(net, ifindex: new_ifindex);
11123 if (err < 0)
11124 goto out;
11125 } else {
11126 /* If there is an ifindex conflict assign a new one */
11127 err = dev_index_reserve(net, ifindex: dev->ifindex);
11128 if (err == -EBUSY)
11129 err = dev_index_reserve(net, ifindex: 0);
11130 if (err < 0)
11131 goto out;
11132 new_ifindex = err;
11133 }
11134
11135 /*
11136 * And now a mini version of register_netdevice unregister_netdevice.
11137 */
11138
11139 /* If device is running close it first. */
11140 dev_close(dev);
11141
11142 /* And unlink it from device chain */
11143 unlist_netdevice(dev, lock: true);
11144
11145 synchronize_net();
11146
11147 /* Shutdown queueing discipline. */
11148 dev_shutdown(dev);
11149
11150 /* Notify protocols, that we are about to destroy
11151 * this device. They should clean all the things.
11152 *
11153 * Note that dev->reg_state stays at NETREG_REGISTERED.
11154 * This is wanted because this way 8021q and macvlan know
11155 * the device is just moving and can keep their slaves up.
11156 */
11157 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
11158 rcu_barrier();
11159
11160 new_nsid = peernet2id_alloc(net: dev_net(dev), peer: net, GFP_KERNEL);
11161
11162 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, change: ~0U, GFP_KERNEL, new_nsid: &new_nsid,
11163 new_ifindex);
11164
11165 /*
11166 * Flush the unicast and multicast chains
11167 */
11168 dev_uc_flush(dev);
11169 dev_mc_flush(dev);
11170
11171 /* Send a netdev-removed uevent to the old namespace */
11172 kobject_uevent(kobj: &dev->dev.kobj, action: KOBJ_REMOVE);
11173 netdev_adjacent_del_links(dev);
11174
11175 /* Move per-net netdevice notifiers that are following the netdevice */
11176 move_netdevice_notifiers_dev_net(dev, net);
11177
11178 /* Actually switch the network namespace */
11179 dev_net_set(dev, net);
11180 dev->ifindex = new_ifindex;
11181
11182 /* Send a netdev-add uevent to the new namespace */
11183 kobject_uevent(kobj: &dev->dev.kobj, action: KOBJ_ADD);
11184 netdev_adjacent_add_links(dev);
11185
11186 if (new_name[0]) /* Rename the netdev to prepared name */
11187 strscpy(p: dev->name, q: new_name, IFNAMSIZ);
11188
11189 /* Fixup kobjects */
11190 err = device_rename(dev: &dev->dev, new_name: dev->name);
11191 WARN_ON(err);
11192
11193 /* Adapt owner in case owning user namespace of target network
11194 * namespace is different from the original one.
11195 */
11196 err = netdev_change_owner(dev, net_old, net_new: net);
11197 WARN_ON(err);
11198
11199 /* Add the device back in the hashes */
11200 list_netdevice(dev);
11201
11202 /* Notify protocols, that a new device appeared. */
11203 call_netdevice_notifiers(NETDEV_REGISTER, dev);
11204
11205 /*
11206 * Prevent userspace races by waiting until the network
11207 * device is fully setup before sending notifications.
11208 */
11209 rtmsg_ifinfo(RTM_NEWLINK, dev, change: ~0U, GFP_KERNEL, portid: 0, NULL);
11210
11211 synchronize_net();
11212 err = 0;
11213out:
11214 return err;
11215}
11216EXPORT_SYMBOL_GPL(__dev_change_net_namespace);
11217
11218static int dev_cpu_dead(unsigned int oldcpu)
11219{
11220 struct sk_buff **list_skb;
11221 struct sk_buff *skb;
11222 unsigned int cpu;
11223 struct softnet_data *sd, *oldsd, *remsd = NULL;
11224
11225 local_irq_disable();
11226 cpu = smp_processor_id();
11227 sd = &per_cpu(softnet_data, cpu);
11228 oldsd = &per_cpu(softnet_data, oldcpu);
11229
11230 /* Find end of our completion_queue. */
11231 list_skb = &sd->completion_queue;
11232 while (*list_skb)
11233 list_skb = &(*list_skb)->next;
11234 /* Append completion queue from offline CPU. */
11235 *list_skb = oldsd->completion_queue;
11236 oldsd->completion_queue = NULL;
11237
11238 /* Append output queue from offline CPU. */
11239 if (oldsd->output_queue) {
11240 *sd->output_queue_tailp = oldsd->output_queue;
11241 sd->output_queue_tailp = oldsd->output_queue_tailp;
11242 oldsd->output_queue = NULL;
11243 oldsd->output_queue_tailp = &oldsd->output_queue;
11244 }
11245 /* Append NAPI poll list from offline CPU, with one exception :
11246 * process_backlog() must be called by cpu owning percpu backlog.
11247 * We properly handle process_queue & input_pkt_queue later.
11248 */
11249 while (!list_empty(head: &oldsd->poll_list)) {
11250 struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
11251 struct napi_struct,
11252 poll_list);
11253
11254 list_del_init(entry: &napi->poll_list);
11255 if (napi->poll == process_backlog)
11256 napi->state = 0;
11257 else
11258 ____napi_schedule(sd, napi);
11259 }
11260
11261 raise_softirq_irqoff(nr: NET_TX_SOFTIRQ);
11262 local_irq_enable();
11263
11264#ifdef CONFIG_RPS
11265 remsd = oldsd->rps_ipi_list;
11266 oldsd->rps_ipi_list = NULL;
11267#endif
11268 /* send out pending IPI's on offline CPU */
11269 net_rps_send_ipi(remsd);
11270
11271 /* Process offline CPU's input_pkt_queue */
11272 while ((skb = __skb_dequeue(list: &oldsd->process_queue))) {
11273 netif_rx(skb);
11274 input_queue_head_incr(sd: oldsd);
11275 }
11276 while ((skb = skb_dequeue(list: &oldsd->input_pkt_queue))) {
11277 netif_rx(skb);
11278 input_queue_head_incr(sd: oldsd);
11279 }
11280
11281 return 0;
11282}
11283
11284/**
11285 * netdev_increment_features - increment feature set by one
11286 * @all: current feature set
11287 * @one: new feature set
11288 * @mask: mask feature set
11289 *
11290 * Computes a new feature set after adding a device with feature set
11291 * @one to the master device with current feature set @all. Will not
11292 * enable anything that is off in @mask. Returns the new feature set.
11293 */
11294netdev_features_t netdev_increment_features(netdev_features_t all,
11295 netdev_features_t one, netdev_features_t mask)
11296{
11297 if (mask & NETIF_F_HW_CSUM)
11298 mask |= NETIF_F_CSUM_MASK;
11299 mask |= NETIF_F_VLAN_CHALLENGED;
11300
11301 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
11302 all &= one | ~NETIF_F_ALL_FOR_ALL;
11303
11304 /* If one device supports hw checksumming, set for all. */
11305 if (all & NETIF_F_HW_CSUM)
11306 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
11307
11308 return all;
11309}
11310EXPORT_SYMBOL(netdev_increment_features);
11311
11312static struct hlist_head * __net_init netdev_create_hash(void)
11313{
11314 int i;
11315 struct hlist_head *hash;
11316
11317 hash = kmalloc_array(NETDEV_HASHENTRIES, size: sizeof(*hash), GFP_KERNEL);
11318 if (hash != NULL)
11319 for (i = 0; i < NETDEV_HASHENTRIES; i++)
11320 INIT_HLIST_HEAD(&hash[i]);
11321
11322 return hash;
11323}
11324
11325/* Initialize per network namespace state */
11326static int __net_init netdev_init(struct net *net)
11327{
11328 BUILD_BUG_ON(GRO_HASH_BUCKETS >
11329 8 * sizeof_field(struct napi_struct, gro_bitmask));
11330
11331 INIT_LIST_HEAD(list: &net->dev_base_head);
11332
11333 net->dev_name_head = netdev_create_hash();
11334 if (net->dev_name_head == NULL)
11335 goto err_name;
11336
11337 net->dev_index_head = netdev_create_hash();
11338 if (net->dev_index_head == NULL)
11339 goto err_idx;
11340
11341 xa_init_flags(xa: &net->dev_by_index, XA_FLAGS_ALLOC1);
11342
11343 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain);
11344
11345 return 0;
11346
11347err_idx:
11348 kfree(objp: net->dev_name_head);
11349err_name:
11350 return -ENOMEM;
11351}
11352
11353/**
11354 * netdev_drivername - network driver for the device
11355 * @dev: network device
11356 *
11357 * Determine network driver for device.
11358 */
11359const char *netdev_drivername(const struct net_device *dev)
11360{
11361 const struct device_driver *driver;
11362 const struct device *parent;
11363 const char *empty = "";
11364
11365 parent = dev->dev.parent;
11366 if (!parent)
11367 return empty;
11368
11369 driver = parent->driver;
11370 if (driver && driver->name)
11371 return driver->name;
11372 return empty;
11373}
11374
11375static void __netdev_printk(const char *level, const struct net_device *dev,
11376 struct va_format *vaf)
11377{
11378 if (dev && dev->dev.parent) {
11379 dev_printk_emit(level: level[1] - '0',
11380 dev: dev->dev.parent,
11381 fmt: "%s %s %s%s: %pV",
11382 dev_driver_string(dev: dev->dev.parent),
11383 dev_name(dev: dev->dev.parent),
11384 netdev_name(dev), netdev_reg_state(dev),
11385 vaf);
11386 } else if (dev) {
11387 printk("%s%s%s: %pV",
11388 level, netdev_name(dev), netdev_reg_state(dev), vaf);
11389 } else {
11390 printk("%s(NULL net_device): %pV", level, vaf);
11391 }
11392}
11393
11394void netdev_printk(const char *level, const struct net_device *dev,
11395 const char *format, ...)
11396{
11397 struct va_format vaf;
11398 va_list args;
11399
11400 va_start(args, format);
11401
11402 vaf.fmt = format;
11403 vaf.va = &args;
11404
11405 __netdev_printk(level, dev, vaf: &vaf);
11406
11407 va_end(args);
11408}
11409EXPORT_SYMBOL(netdev_printk);
11410
11411#define define_netdev_printk_level(func, level) \
11412void func(const struct net_device *dev, const char *fmt, ...) \
11413{ \
11414 struct va_format vaf; \
11415 va_list args; \
11416 \
11417 va_start(args, fmt); \
11418 \
11419 vaf.fmt = fmt; \
11420 vaf.va = &args; \
11421 \
11422 __netdev_printk(level, dev, &vaf); \
11423 \
11424 va_end(args); \
11425} \
11426EXPORT_SYMBOL(func);
11427
11428define_netdev_printk_level(netdev_emerg, KERN_EMERG);
11429define_netdev_printk_level(netdev_alert, KERN_ALERT);
11430define_netdev_printk_level(netdev_crit, KERN_CRIT);
11431define_netdev_printk_level(netdev_err, KERN_ERR);
11432define_netdev_printk_level(netdev_warn, KERN_WARNING);
11433define_netdev_printk_level(netdev_notice, KERN_NOTICE);
11434define_netdev_printk_level(netdev_info, KERN_INFO);
11435
11436static void __net_exit netdev_exit(struct net *net)
11437{
11438 kfree(objp: net->dev_name_head);
11439 kfree(objp: net->dev_index_head);
11440 xa_destroy(&net->dev_by_index);
11441 if (net != &init_net)
11442 WARN_ON_ONCE(!list_empty(&net->dev_base_head));
11443}
11444
11445static struct pernet_operations __net_initdata netdev_net_ops = {
11446 .init = netdev_init,
11447 .exit = netdev_exit,
11448};
11449
11450static void __net_exit default_device_exit_net(struct net *net)
11451{
11452 struct net_device *dev, *aux;
11453 /*
11454 * Push all migratable network devices back to the
11455 * initial network namespace
11456 */
11457 ASSERT_RTNL();
11458 for_each_netdev_safe(net, dev, aux) {
11459 int err;
11460 char fb_name[IFNAMSIZ];
11461
11462 /* Ignore unmoveable devices (i.e. loopback) */
11463 if (dev->features & NETIF_F_NETNS_LOCAL)
11464 continue;
11465
11466 /* Leave virtual devices for the generic cleanup */
11467 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund)
11468 continue;
11469
11470 /* Push remaining network devices to init_net */
11471 snprintf(buf: fb_name, IFNAMSIZ, fmt: "dev%d", dev->ifindex);
11472 if (netdev_name_in_use(&init_net, fb_name))
11473 snprintf(buf: fb_name, IFNAMSIZ, fmt: "dev%%d");
11474 err = dev_change_net_namespace(dev, net: &init_net, pat: fb_name);
11475 if (err) {
11476 pr_emerg("%s: failed to move %s to init_net: %d\n",
11477 __func__, dev->name, err);
11478 BUG();
11479 }
11480 }
11481}
11482
11483static void __net_exit default_device_exit_batch(struct list_head *net_list)
11484{
11485 /* At exit all network devices most be removed from a network
11486 * namespace. Do this in the reverse order of registration.
11487 * Do this across as many network namespaces as possible to
11488 * improve batching efficiency.
11489 */
11490 struct net_device *dev;
11491 struct net *net;
11492 LIST_HEAD(dev_kill_list);
11493
11494 rtnl_lock();
11495 list_for_each_entry(net, net_list, exit_list) {
11496 default_device_exit_net(net);
11497 cond_resched();
11498 }
11499
11500 list_for_each_entry(net, net_list, exit_list) {
11501 for_each_netdev_reverse(net, dev) {
11502 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
11503 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
11504 else
11505 unregister_netdevice_queue(dev, &dev_kill_list);
11506 }
11507 }
11508 unregister_netdevice_many(&dev_kill_list);
11509 rtnl_unlock();
11510}
11511
11512static struct pernet_operations __net_initdata default_device_ops = {
11513 .exit_batch = default_device_exit_batch,
11514};
11515
11516/*
11517 * Initialize the DEV module. At boot time this walks the device list and
11518 * unhooks any devices that fail to initialise (normally hardware not
11519 * present) and leaves us with a valid list of present and active devices.
11520 *
11521 */
11522
11523/*
11524 * This is called single threaded during boot, so no need
11525 * to take the rtnl semaphore.
11526 */
11527static int __init net_dev_init(void)
11528{
11529 int i, rc = -ENOMEM;
11530
11531 BUG_ON(!dev_boot_phase);
11532
11533 if (dev_proc_init())
11534 goto out;
11535
11536 if (netdev_kobject_init())
11537 goto out;
11538
11539 INIT_LIST_HEAD(list: &ptype_all);
11540 for (i = 0; i < PTYPE_HASH_SIZE; i++)
11541 INIT_LIST_HEAD(list: &ptype_base[i]);
11542
11543 if (register_pernet_subsys(&netdev_net_ops))
11544 goto out;
11545
11546 /*
11547 * Initialise the packet receive queues.
11548 */
11549
11550 for_each_possible_cpu(i) {
11551 struct work_struct *flush = per_cpu_ptr(&flush_works, i);
11552 struct softnet_data *sd = &per_cpu(softnet_data, i);
11553
11554 INIT_WORK(flush, flush_backlog);
11555
11556 skb_queue_head_init(list: &sd->input_pkt_queue);
11557 skb_queue_head_init(list: &sd->process_queue);
11558#ifdef CONFIG_XFRM_OFFLOAD
11559 skb_queue_head_init(list: &sd->xfrm_backlog);
11560#endif
11561 INIT_LIST_HEAD(list: &sd->poll_list);
11562 sd->output_queue_tailp = &sd->output_queue;
11563#ifdef CONFIG_RPS
11564 INIT_CSD(&sd->csd, rps_trigger_softirq, sd);
11565 sd->cpu = i;
11566#endif
11567 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd);
11568 spin_lock_init(&sd->defer_lock);
11569
11570 init_gro_hash(napi: &sd->backlog);
11571 sd->backlog.poll = process_backlog;
11572 sd->backlog.weight = weight_p;
11573 }
11574
11575 dev_boot_phase = 0;
11576
11577 /* The loopback device is special if any other network devices
11578 * is present in a network namespace the loopback device must
11579 * be present. Since we now dynamically allocate and free the
11580 * loopback device ensure this invariant is maintained by
11581 * keeping the loopback device as the first device on the
11582 * list of network devices. Ensuring the loopback devices
11583 * is the first device that appears and the last network device
11584 * that disappears.
11585 */
11586 if (register_pernet_device(&loopback_net_ops))
11587 goto out;
11588
11589 if (register_pernet_device(&default_device_ops))
11590 goto out;
11591
11592 open_softirq(nr: NET_TX_SOFTIRQ, action: net_tx_action);
11593 open_softirq(nr: NET_RX_SOFTIRQ, action: net_rx_action);
11594
11595 rc = cpuhp_setup_state_nocalls(state: CPUHP_NET_DEV_DEAD, name: "net/dev:dead",
11596 NULL, teardown: dev_cpu_dead);
11597 WARN_ON(rc < 0);
11598 rc = 0;
11599out:
11600 return rc;
11601}
11602
11603subsys_initcall(net_dev_init);
11604

source code of linux/net/core/dev.c