1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
4 *
5 * Basic Transport Functions exploiting Infiniband API
6 *
7 * Copyright IBM Corp. 2016
8 *
9 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
10 */
11
12#include <linux/socket.h>
13#include <linux/if_vlan.h>
14#include <linux/random.h>
15#include <linux/workqueue.h>
16#include <linux/wait.h>
17#include <linux/reboot.h>
18#include <linux/mutex.h>
19#include <linux/list.h>
20#include <linux/smc.h>
21#include <net/tcp.h>
22#include <net/sock.h>
23#include <rdma/ib_verbs.h>
24#include <rdma/ib_cache.h>
25
26#include "smc.h"
27#include "smc_clc.h"
28#include "smc_core.h"
29#include "smc_ib.h"
30#include "smc_wr.h"
31#include "smc_llc.h"
32#include "smc_cdc.h"
33#include "smc_close.h"
34#include "smc_ism.h"
35#include "smc_netlink.h"
36#include "smc_stats.h"
37#include "smc_tracepoint.h"
38
39#define SMC_LGR_NUM_INCR 256
40#define SMC_LGR_FREE_DELAY_SERV (600 * HZ)
41#define SMC_LGR_FREE_DELAY_CLNT (SMC_LGR_FREE_DELAY_SERV + 10 * HZ)
42
43struct smc_lgr_list smc_lgr_list = { /* established link groups */
44 .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
45 .list = LIST_HEAD_INIT(smc_lgr_list.list),
46 .num = 0,
47};
48
49static atomic_t lgr_cnt = ATOMIC_INIT(0); /* number of existing link groups */
50static DECLARE_WAIT_QUEUE_HEAD(lgrs_deleted);
51
52static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
53 struct smc_buf_desc *buf_desc);
54static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
55
56static void smc_link_down_work(struct work_struct *work);
57
58/* return head of link group list and its lock for a given link group */
59static inline struct list_head *smc_lgr_list_head(struct smc_link_group *lgr,
60 spinlock_t **lgr_lock)
61{
62 if (lgr->is_smcd) {
63 *lgr_lock = &lgr->smcd->lgr_lock;
64 return &lgr->smcd->lgr_list;
65 }
66
67 *lgr_lock = &smc_lgr_list.lock;
68 return &smc_lgr_list.list;
69}
70
71static void smc_ibdev_cnt_inc(struct smc_link *lnk)
72{
73 atomic_inc(v: &lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
74}
75
76static void smc_ibdev_cnt_dec(struct smc_link *lnk)
77{
78 atomic_dec(v: &lnk->smcibdev->lnk_cnt_by_port[lnk->ibport - 1]);
79}
80
81static void smc_lgr_schedule_free_work(struct smc_link_group *lgr)
82{
83 /* client link group creation always follows the server link group
84 * creation. For client use a somewhat higher removal delay time,
85 * otherwise there is a risk of out-of-sync link groups.
86 */
87 if (!lgr->freeing) {
88 mod_delayed_work(wq: system_wq, dwork: &lgr->free_work,
89 delay: (!lgr->is_smcd && lgr->role == SMC_CLNT) ?
90 SMC_LGR_FREE_DELAY_CLNT :
91 SMC_LGR_FREE_DELAY_SERV);
92 }
93}
94
95/* Register connection's alert token in our lookup structure.
96 * To use rbtrees we have to implement our own insert core.
97 * Requires @conns_lock
98 * @smc connection to register
99 * Returns 0 on success, != otherwise.
100 */
101static void smc_lgr_add_alert_token(struct smc_connection *conn)
102{
103 struct rb_node **link, *parent = NULL;
104 u32 token = conn->alert_token_local;
105
106 link = &conn->lgr->conns_all.rb_node;
107 while (*link) {
108 struct smc_connection *cur = rb_entry(*link,
109 struct smc_connection, alert_node);
110
111 parent = *link;
112 if (cur->alert_token_local > token)
113 link = &parent->rb_left;
114 else
115 link = &parent->rb_right;
116 }
117 /* Put the new node there */
118 rb_link_node(node: &conn->alert_node, parent, rb_link: link);
119 rb_insert_color(&conn->alert_node, &conn->lgr->conns_all);
120}
121
122/* assign an SMC-R link to the connection */
123static int smcr_lgr_conn_assign_link(struct smc_connection *conn, bool first)
124{
125 enum smc_link_state expected = first ? SMC_LNK_ACTIVATING :
126 SMC_LNK_ACTIVE;
127 int i, j;
128
129 /* do link balancing */
130 conn->lnk = NULL; /* reset conn->lnk first */
131 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
132 struct smc_link *lnk = &conn->lgr->lnk[i];
133
134 if (lnk->state != expected || lnk->link_is_asym)
135 continue;
136 if (conn->lgr->role == SMC_CLNT) {
137 conn->lnk = lnk; /* temporary, SMC server assigns link*/
138 break;
139 }
140 if (conn->lgr->conns_num % 2) {
141 for (j = i + 1; j < SMC_LINKS_PER_LGR_MAX; j++) {
142 struct smc_link *lnk2;
143
144 lnk2 = &conn->lgr->lnk[j];
145 if (lnk2->state == expected &&
146 !lnk2->link_is_asym) {
147 conn->lnk = lnk2;
148 break;
149 }
150 }
151 }
152 if (!conn->lnk)
153 conn->lnk = lnk;
154 break;
155 }
156 if (!conn->lnk)
157 return SMC_CLC_DECL_NOACTLINK;
158 atomic_inc(v: &conn->lnk->conn_cnt);
159 return 0;
160}
161
162/* Register connection in link group by assigning an alert token
163 * registered in a search tree.
164 * Requires @conns_lock
165 * Note that '0' is a reserved value and not assigned.
166 */
167static int smc_lgr_register_conn(struct smc_connection *conn, bool first)
168{
169 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
170 static atomic_t nexttoken = ATOMIC_INIT(0);
171 int rc;
172
173 if (!conn->lgr->is_smcd) {
174 rc = smcr_lgr_conn_assign_link(conn, first);
175 if (rc) {
176 conn->lgr = NULL;
177 return rc;
178 }
179 }
180 /* find a new alert_token_local value not yet used by some connection
181 * in this link group
182 */
183 sock_hold(sk: &smc->sk); /* sock_put in smc_lgr_unregister_conn() */
184 while (!conn->alert_token_local) {
185 conn->alert_token_local = atomic_inc_return(v: &nexttoken);
186 if (smc_lgr_find_conn(token: conn->alert_token_local, lgr: conn->lgr))
187 conn->alert_token_local = 0;
188 }
189 smc_lgr_add_alert_token(conn);
190 conn->lgr->conns_num++;
191 return 0;
192}
193
194/* Unregister connection and reset the alert token of the given connection<
195 */
196static void __smc_lgr_unregister_conn(struct smc_connection *conn)
197{
198 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
199 struct smc_link_group *lgr = conn->lgr;
200
201 rb_erase(&conn->alert_node, &lgr->conns_all);
202 if (conn->lnk)
203 atomic_dec(v: &conn->lnk->conn_cnt);
204 lgr->conns_num--;
205 conn->alert_token_local = 0;
206 sock_put(sk: &smc->sk); /* sock_hold in smc_lgr_register_conn() */
207}
208
209/* Unregister connection from lgr
210 */
211static void smc_lgr_unregister_conn(struct smc_connection *conn)
212{
213 struct smc_link_group *lgr = conn->lgr;
214
215 if (!smc_conn_lgr_valid(conn))
216 return;
217 write_lock_bh(&lgr->conns_lock);
218 if (conn->alert_token_local) {
219 __smc_lgr_unregister_conn(conn);
220 }
221 write_unlock_bh(&lgr->conns_lock);
222}
223
224int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
225{
226 struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(c: cb);
227 char hostname[SMC_MAX_HOSTNAME_LEN + 1];
228 char smc_seid[SMC_MAX_EID_LEN + 1];
229 struct nlattr *attrs;
230 u8 *seid = NULL;
231 u8 *host = NULL;
232 void *nlh;
233
234 nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, seq: cb->nlh->nlmsg_seq,
235 family: &smc_gen_nl_family, NLM_F_MULTI,
236 cmd: SMC_NETLINK_GET_SYS_INFO);
237 if (!nlh)
238 goto errmsg;
239 if (cb_ctx->pos[0])
240 goto errout;
241 attrs = nla_nest_start(skb, attrtype: SMC_GEN_SYS_INFO);
242 if (!attrs)
243 goto errout;
244 if (nla_put_u8(skb, attrtype: SMC_NLA_SYS_VER, SMC_V2))
245 goto errattr;
246 if (nla_put_u8(skb, attrtype: SMC_NLA_SYS_REL, SMC_RELEASE))
247 goto errattr;
248 if (nla_put_u8(skb, attrtype: SMC_NLA_SYS_IS_ISM_V2, value: smc_ism_is_v2_capable()))
249 goto errattr;
250 if (nla_put_u8(skb, attrtype: SMC_NLA_SYS_IS_SMCR_V2, value: true))
251 goto errattr;
252 smc_clc_get_hostname(host: &host);
253 if (host) {
254 memcpy(hostname, host, SMC_MAX_HOSTNAME_LEN);
255 hostname[SMC_MAX_HOSTNAME_LEN] = 0;
256 if (nla_put_string(skb, attrtype: SMC_NLA_SYS_LOCAL_HOST, str: hostname))
257 goto errattr;
258 }
259 if (smc_ism_is_v2_capable()) {
260 smc_ism_get_system_eid(eid: &seid);
261 memcpy(smc_seid, seid, SMC_MAX_EID_LEN);
262 smc_seid[SMC_MAX_EID_LEN] = 0;
263 if (nla_put_string(skb, attrtype: SMC_NLA_SYS_SEID, str: smc_seid))
264 goto errattr;
265 }
266 nla_nest_end(skb, start: attrs);
267 genlmsg_end(skb, hdr: nlh);
268 cb_ctx->pos[0] = 1;
269 return skb->len;
270
271errattr:
272 nla_nest_cancel(skb, start: attrs);
273errout:
274 genlmsg_cancel(skb, hdr: nlh);
275errmsg:
276 return skb->len;
277}
278
279/* Fill SMC_NLA_LGR_D_V2_COMMON/SMC_NLA_LGR_R_V2_COMMON nested attributes */
280static int smc_nl_fill_lgr_v2_common(struct smc_link_group *lgr,
281 struct sk_buff *skb,
282 struct netlink_callback *cb,
283 struct nlattr *v2_attrs)
284{
285 char smc_host[SMC_MAX_HOSTNAME_LEN + 1];
286 char smc_eid[SMC_MAX_EID_LEN + 1];
287
288 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_V2_VER, value: lgr->smc_version))
289 goto errv2attr;
290 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_V2_REL, value: lgr->peer_smc_release))
291 goto errv2attr;
292 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_V2_OS, value: lgr->peer_os))
293 goto errv2attr;
294 memcpy(smc_host, lgr->peer_hostname, SMC_MAX_HOSTNAME_LEN);
295 smc_host[SMC_MAX_HOSTNAME_LEN] = 0;
296 if (nla_put_string(skb, attrtype: SMC_NLA_LGR_V2_PEER_HOST, str: smc_host))
297 goto errv2attr;
298 memcpy(smc_eid, lgr->negotiated_eid, SMC_MAX_EID_LEN);
299 smc_eid[SMC_MAX_EID_LEN] = 0;
300 if (nla_put_string(skb, attrtype: SMC_NLA_LGR_V2_NEG_EID, str: smc_eid))
301 goto errv2attr;
302
303 nla_nest_end(skb, start: v2_attrs);
304 return 0;
305
306errv2attr:
307 nla_nest_cancel(skb, start: v2_attrs);
308 return -EMSGSIZE;
309}
310
311static int smc_nl_fill_smcr_lgr_v2(struct smc_link_group *lgr,
312 struct sk_buff *skb,
313 struct netlink_callback *cb)
314{
315 struct nlattr *v2_attrs;
316
317 v2_attrs = nla_nest_start(skb, attrtype: SMC_NLA_LGR_R_V2);
318 if (!v2_attrs)
319 goto errattr;
320 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_R_V2_DIRECT, value: !lgr->uses_gateway))
321 goto errv2attr;
322 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_R_V2_MAX_CONNS, value: lgr->max_conns))
323 goto errv2attr;
324 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_R_V2_MAX_LINKS, value: lgr->max_links))
325 goto errv2attr;
326
327 nla_nest_end(skb, start: v2_attrs);
328 return 0;
329
330errv2attr:
331 nla_nest_cancel(skb, start: v2_attrs);
332errattr:
333 return -EMSGSIZE;
334}
335
336static int smc_nl_fill_lgr(struct smc_link_group *lgr,
337 struct sk_buff *skb,
338 struct netlink_callback *cb)
339{
340 char smc_target[SMC_MAX_PNETID_LEN + 1];
341 struct nlattr *attrs, *v2_attrs;
342
343 attrs = nla_nest_start(skb, attrtype: SMC_GEN_LGR_SMCR);
344 if (!attrs)
345 goto errout;
346
347 if (nla_put_u32(skb, attrtype: SMC_NLA_LGR_R_ID, value: *((u32 *)&lgr->id)))
348 goto errattr;
349 if (nla_put_u32(skb, attrtype: SMC_NLA_LGR_R_CONNS_NUM, value: lgr->conns_num))
350 goto errattr;
351 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_R_ROLE, value: lgr->role))
352 goto errattr;
353 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_R_TYPE, value: lgr->type))
354 goto errattr;
355 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_R_BUF_TYPE, value: lgr->buf_type))
356 goto errattr;
357 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_R_VLAN_ID, value: lgr->vlan_id))
358 goto errattr;
359 if (nla_put_u64_64bit(skb, attrtype: SMC_NLA_LGR_R_NET_COOKIE,
360 value: lgr->net->net_cookie, padattr: SMC_NLA_LGR_R_PAD))
361 goto errattr;
362 memcpy(smc_target, lgr->pnet_id, SMC_MAX_PNETID_LEN);
363 smc_target[SMC_MAX_PNETID_LEN] = 0;
364 if (nla_put_string(skb, attrtype: SMC_NLA_LGR_R_PNETID, str: smc_target))
365 goto errattr;
366 if (lgr->smc_version > SMC_V1) {
367 v2_attrs = nla_nest_start(skb, attrtype: SMC_NLA_LGR_R_V2_COMMON);
368 if (!v2_attrs)
369 goto errattr;
370 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
371 goto errattr;
372 if (smc_nl_fill_smcr_lgr_v2(lgr, skb, cb))
373 goto errattr;
374 }
375
376 nla_nest_end(skb, start: attrs);
377 return 0;
378errattr:
379 nla_nest_cancel(skb, start: attrs);
380errout:
381 return -EMSGSIZE;
382}
383
384static int smc_nl_fill_lgr_link(struct smc_link_group *lgr,
385 struct smc_link *link,
386 struct sk_buff *skb,
387 struct netlink_callback *cb)
388{
389 char smc_ibname[IB_DEVICE_NAME_MAX];
390 u8 smc_gid_target[41];
391 struct nlattr *attrs;
392 u32 link_uid = 0;
393 void *nlh;
394
395 nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, seq: cb->nlh->nlmsg_seq,
396 family: &smc_gen_nl_family, NLM_F_MULTI,
397 cmd: SMC_NETLINK_GET_LINK_SMCR);
398 if (!nlh)
399 goto errmsg;
400
401 attrs = nla_nest_start(skb, attrtype: SMC_GEN_LINK_SMCR);
402 if (!attrs)
403 goto errout;
404
405 if (nla_put_u8(skb, attrtype: SMC_NLA_LINK_ID, value: link->link_id))
406 goto errattr;
407 if (nla_put_u32(skb, attrtype: SMC_NLA_LINK_STATE, value: link->state))
408 goto errattr;
409 if (nla_put_u32(skb, attrtype: SMC_NLA_LINK_CONN_CNT,
410 value: atomic_read(v: &link->conn_cnt)))
411 goto errattr;
412 if (nla_put_u8(skb, attrtype: SMC_NLA_LINK_IB_PORT, value: link->ibport))
413 goto errattr;
414 if (nla_put_u32(skb, attrtype: SMC_NLA_LINK_NET_DEV, value: link->ndev_ifidx))
415 goto errattr;
416 snprintf(buf: smc_ibname, size: sizeof(smc_ibname), fmt: "%s", link->ibname);
417 if (nla_put_string(skb, attrtype: SMC_NLA_LINK_IB_DEV, str: smc_ibname))
418 goto errattr;
419 memcpy(&link_uid, link->link_uid, sizeof(link_uid));
420 if (nla_put_u32(skb, attrtype: SMC_NLA_LINK_UID, value: link_uid))
421 goto errattr;
422 memcpy(&link_uid, link->peer_link_uid, sizeof(link_uid));
423 if (nla_put_u32(skb, attrtype: SMC_NLA_LINK_PEER_UID, value: link_uid))
424 goto errattr;
425 memset(smc_gid_target, 0, sizeof(smc_gid_target));
426 smc_gid_be16_convert(buf: smc_gid_target, gid_raw: link->gid);
427 if (nla_put_string(skb, attrtype: SMC_NLA_LINK_GID, str: smc_gid_target))
428 goto errattr;
429 memset(smc_gid_target, 0, sizeof(smc_gid_target));
430 smc_gid_be16_convert(buf: smc_gid_target, gid_raw: link->peer_gid);
431 if (nla_put_string(skb, attrtype: SMC_NLA_LINK_PEER_GID, str: smc_gid_target))
432 goto errattr;
433
434 nla_nest_end(skb, start: attrs);
435 genlmsg_end(skb, hdr: nlh);
436 return 0;
437errattr:
438 nla_nest_cancel(skb, start: attrs);
439errout:
440 genlmsg_cancel(skb, hdr: nlh);
441errmsg:
442 return -EMSGSIZE;
443}
444
445static int smc_nl_handle_lgr(struct smc_link_group *lgr,
446 struct sk_buff *skb,
447 struct netlink_callback *cb,
448 bool list_links)
449{
450 void *nlh;
451 int i;
452
453 nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, seq: cb->nlh->nlmsg_seq,
454 family: &smc_gen_nl_family, NLM_F_MULTI,
455 cmd: SMC_NETLINK_GET_LGR_SMCR);
456 if (!nlh)
457 goto errmsg;
458 if (smc_nl_fill_lgr(lgr, skb, cb))
459 goto errout;
460
461 genlmsg_end(skb, hdr: nlh);
462 if (!list_links)
463 goto out;
464 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
465 if (!smc_link_usable(lnk: &lgr->lnk[i]))
466 continue;
467 if (smc_nl_fill_lgr_link(lgr, link: &lgr->lnk[i], skb, cb))
468 goto errout;
469 }
470out:
471 return 0;
472
473errout:
474 genlmsg_cancel(skb, hdr: nlh);
475errmsg:
476 return -EMSGSIZE;
477}
478
479static void smc_nl_fill_lgr_list(struct smc_lgr_list *smc_lgr,
480 struct sk_buff *skb,
481 struct netlink_callback *cb,
482 bool list_links)
483{
484 struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(c: cb);
485 struct smc_link_group *lgr;
486 int snum = cb_ctx->pos[0];
487 int num = 0;
488
489 spin_lock_bh(lock: &smc_lgr->lock);
490 list_for_each_entry(lgr, &smc_lgr->list, list) {
491 if (num < snum)
492 goto next;
493 if (smc_nl_handle_lgr(lgr, skb, cb, list_links))
494 goto errout;
495next:
496 num++;
497 }
498errout:
499 spin_unlock_bh(lock: &smc_lgr->lock);
500 cb_ctx->pos[0] = num;
501}
502
503static int smc_nl_fill_smcd_lgr(struct smc_link_group *lgr,
504 struct sk_buff *skb,
505 struct netlink_callback *cb)
506{
507 char smc_pnet[SMC_MAX_PNETID_LEN + 1];
508 struct smcd_dev *smcd = lgr->smcd;
509 struct nlattr *attrs;
510 void *nlh;
511
512 nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, seq: cb->nlh->nlmsg_seq,
513 family: &smc_gen_nl_family, NLM_F_MULTI,
514 cmd: SMC_NETLINK_GET_LGR_SMCD);
515 if (!nlh)
516 goto errmsg;
517
518 attrs = nla_nest_start(skb, attrtype: SMC_GEN_LGR_SMCD);
519 if (!attrs)
520 goto errout;
521
522 if (nla_put_u32(skb, attrtype: SMC_NLA_LGR_D_ID, value: *((u32 *)&lgr->id)))
523 goto errattr;
524 if (nla_put_u64_64bit(skb, attrtype: SMC_NLA_LGR_D_GID,
525 value: smcd->ops->get_local_gid(smcd),
526 padattr: SMC_NLA_LGR_D_PAD))
527 goto errattr;
528 if (nla_put_u64_64bit(skb, attrtype: SMC_NLA_LGR_D_PEER_GID, value: lgr->peer_gid,
529 padattr: SMC_NLA_LGR_D_PAD))
530 goto errattr;
531 if (nla_put_u8(skb, attrtype: SMC_NLA_LGR_D_VLAN_ID, value: lgr->vlan_id))
532 goto errattr;
533 if (nla_put_u32(skb, attrtype: SMC_NLA_LGR_D_CONNS_NUM, value: lgr->conns_num))
534 goto errattr;
535 if (nla_put_u32(skb, attrtype: SMC_NLA_LGR_D_CHID, value: smc_ism_get_chid(dev: lgr->smcd)))
536 goto errattr;
537 memcpy(smc_pnet, lgr->smcd->pnetid, SMC_MAX_PNETID_LEN);
538 smc_pnet[SMC_MAX_PNETID_LEN] = 0;
539 if (nla_put_string(skb, attrtype: SMC_NLA_LGR_D_PNETID, str: smc_pnet))
540 goto errattr;
541 if (lgr->smc_version > SMC_V1) {
542 struct nlattr *v2_attrs;
543
544 v2_attrs = nla_nest_start(skb, attrtype: SMC_NLA_LGR_D_V2_COMMON);
545 if (!v2_attrs)
546 goto errattr;
547 if (smc_nl_fill_lgr_v2_common(lgr, skb, cb, v2_attrs))
548 goto errattr;
549 }
550 nla_nest_end(skb, start: attrs);
551 genlmsg_end(skb, hdr: nlh);
552 return 0;
553
554errattr:
555 nla_nest_cancel(skb, start: attrs);
556errout:
557 genlmsg_cancel(skb, hdr: nlh);
558errmsg:
559 return -EMSGSIZE;
560}
561
562static int smc_nl_handle_smcd_lgr(struct smcd_dev *dev,
563 struct sk_buff *skb,
564 struct netlink_callback *cb)
565{
566 struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(c: cb);
567 struct smc_link_group *lgr;
568 int snum = cb_ctx->pos[1];
569 int rc = 0, num = 0;
570
571 spin_lock_bh(lock: &dev->lgr_lock);
572 list_for_each_entry(lgr, &dev->lgr_list, list) {
573 if (!lgr->is_smcd)
574 continue;
575 if (num < snum)
576 goto next;
577 rc = smc_nl_fill_smcd_lgr(lgr, skb, cb);
578 if (rc)
579 goto errout;
580next:
581 num++;
582 }
583errout:
584 spin_unlock_bh(lock: &dev->lgr_lock);
585 cb_ctx->pos[1] = num;
586 return rc;
587}
588
589static int smc_nl_fill_smcd_dev(struct smcd_dev_list *dev_list,
590 struct sk_buff *skb,
591 struct netlink_callback *cb)
592{
593 struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(c: cb);
594 struct smcd_dev *smcd_dev;
595 int snum = cb_ctx->pos[0];
596 int rc = 0, num = 0;
597
598 mutex_lock(&dev_list->mutex);
599 list_for_each_entry(smcd_dev, &dev_list->list, list) {
600 if (list_empty(head: &smcd_dev->lgr_list))
601 continue;
602 if (num < snum)
603 goto next;
604 rc = smc_nl_handle_smcd_lgr(dev: smcd_dev, skb, cb);
605 if (rc)
606 goto errout;
607next:
608 num++;
609 }
610errout:
611 mutex_unlock(lock: &dev_list->mutex);
612 cb_ctx->pos[0] = num;
613 return rc;
614}
615
616int smcr_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
617{
618 bool list_links = false;
619
620 smc_nl_fill_lgr_list(smc_lgr: &smc_lgr_list, skb, cb, list_links);
621 return skb->len;
622}
623
624int smcr_nl_get_link(struct sk_buff *skb, struct netlink_callback *cb)
625{
626 bool list_links = true;
627
628 smc_nl_fill_lgr_list(smc_lgr: &smc_lgr_list, skb, cb, list_links);
629 return skb->len;
630}
631
632int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb)
633{
634 smc_nl_fill_smcd_dev(dev_list: &smcd_dev_list, skb, cb);
635 return skb->len;
636}
637
638void smc_lgr_cleanup_early(struct smc_link_group *lgr)
639{
640 spinlock_t *lgr_lock;
641
642 if (!lgr)
643 return;
644
645 smc_lgr_list_head(lgr, lgr_lock: &lgr_lock);
646 spin_lock_bh(lock: lgr_lock);
647 /* do not use this link group for new connections */
648 if (!list_empty(head: &lgr->list))
649 list_del_init(entry: &lgr->list);
650 spin_unlock_bh(lock: lgr_lock);
651 __smc_lgr_terminate(lgr, soft: true);
652}
653
654static void smcr_lgr_link_deactivate_all(struct smc_link_group *lgr)
655{
656 int i;
657
658 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
659 struct smc_link *lnk = &lgr->lnk[i];
660
661 if (smc_link_sendable(lnk))
662 lnk->state = SMC_LNK_INACTIVE;
663 }
664 wake_up_all(&lgr->llc_msg_waiter);
665 wake_up_all(&lgr->llc_flow_waiter);
666}
667
668static void smc_lgr_free(struct smc_link_group *lgr);
669
670static void smc_lgr_free_work(struct work_struct *work)
671{
672 struct smc_link_group *lgr = container_of(to_delayed_work(work),
673 struct smc_link_group,
674 free_work);
675 spinlock_t *lgr_lock;
676 bool conns;
677
678 smc_lgr_list_head(lgr, lgr_lock: &lgr_lock);
679 spin_lock_bh(lock: lgr_lock);
680 if (lgr->freeing) {
681 spin_unlock_bh(lock: lgr_lock);
682 return;
683 }
684 read_lock_bh(&lgr->conns_lock);
685 conns = RB_EMPTY_ROOT(&lgr->conns_all);
686 read_unlock_bh(&lgr->conns_lock);
687 if (!conns) { /* number of lgr connections is no longer zero */
688 spin_unlock_bh(lock: lgr_lock);
689 return;
690 }
691 list_del_init(entry: &lgr->list); /* remove from smc_lgr_list */
692 lgr->freeing = 1; /* this instance does the freeing, no new schedule */
693 spin_unlock_bh(lock: lgr_lock);
694 cancel_delayed_work(dwork: &lgr->free_work);
695
696 if (!lgr->is_smcd && !lgr->terminating)
697 smc_llc_send_link_delete_all(lgr, ord: true,
698 SMC_LLC_DEL_PROG_INIT_TERM);
699 if (lgr->is_smcd && !lgr->terminating)
700 smc_ism_signal_shutdown(lgr);
701 if (!lgr->is_smcd)
702 smcr_lgr_link_deactivate_all(lgr);
703 smc_lgr_free(lgr);
704}
705
706static void smc_lgr_terminate_work(struct work_struct *work)
707{
708 struct smc_link_group *lgr = container_of(work, struct smc_link_group,
709 terminate_work);
710
711 __smc_lgr_terminate(lgr, soft: true);
712}
713
714/* return next unique link id for the lgr */
715static u8 smcr_next_link_id(struct smc_link_group *lgr)
716{
717 u8 link_id;
718 int i;
719
720 while (1) {
721again:
722 link_id = ++lgr->next_link_id;
723 if (!link_id) /* skip zero as link_id */
724 link_id = ++lgr->next_link_id;
725 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
726 if (smc_link_usable(lnk: &lgr->lnk[i]) &&
727 lgr->lnk[i].link_id == link_id)
728 goto again;
729 }
730 break;
731 }
732 return link_id;
733}
734
735static void smcr_copy_dev_info_to_link(struct smc_link *link)
736{
737 struct smc_ib_device *smcibdev = link->smcibdev;
738
739 snprintf(buf: link->ibname, size: sizeof(link->ibname), fmt: "%s",
740 smcibdev->ibdev->name);
741 link->ndev_ifidx = smcibdev->ndev_ifidx[link->ibport - 1];
742}
743
744int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
745 u8 link_idx, struct smc_init_info *ini)
746{
747 struct smc_ib_device *smcibdev;
748 u8 rndvec[3];
749 int rc;
750
751 if (lgr->smc_version == SMC_V2) {
752 lnk->smcibdev = ini->smcrv2.ib_dev_v2;
753 lnk->ibport = ini->smcrv2.ib_port_v2;
754 } else {
755 lnk->smcibdev = ini->ib_dev;
756 lnk->ibport = ini->ib_port;
757 }
758 get_device(dev: &lnk->smcibdev->ibdev->dev);
759 atomic_inc(v: &lnk->smcibdev->lnk_cnt);
760 refcount_set(r: &lnk->refcnt, n: 1); /* link refcnt is set to 1 */
761 lnk->clearing = 0;
762 lnk->path_mtu = lnk->smcibdev->pattr[lnk->ibport - 1].active_mtu;
763 lnk->link_id = smcr_next_link_id(lgr);
764 lnk->lgr = lgr;
765 smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */
766 lnk->link_idx = link_idx;
767 lnk->wr_rx_id_compl = 0;
768 smc_ibdev_cnt_inc(lnk);
769 smcr_copy_dev_info_to_link(link: lnk);
770 atomic_set(v: &lnk->conn_cnt, i: 0);
771 smc_llc_link_set_uid(link: lnk);
772 INIT_WORK(&lnk->link_down_wrk, smc_link_down_work);
773 if (!lnk->smcibdev->initialized) {
774 rc = (int)smc_ib_setup_per_ibdev(smcibdev: lnk->smcibdev);
775 if (rc)
776 goto out;
777 }
778 get_random_bytes(buf: rndvec, len: sizeof(rndvec));
779 lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) +
780 (rndvec[2] << 16);
781 rc = smc_ib_determine_gid(smcibdev: lnk->smcibdev, ibport: lnk->ibport,
782 vlan_id: ini->vlan_id, gid: lnk->gid, sgid_index: &lnk->sgid_index,
783 smcrv2: lgr->smc_version == SMC_V2 ?
784 &ini->smcrv2 : NULL);
785 if (rc)
786 goto out;
787 rc = smc_llc_link_init(link: lnk);
788 if (rc)
789 goto out;
790 rc = smc_wr_alloc_link_mem(lnk);
791 if (rc)
792 goto clear_llc_lnk;
793 rc = smc_ib_create_protection_domain(lnk);
794 if (rc)
795 goto free_link_mem;
796 rc = smc_ib_create_queue_pair(lnk);
797 if (rc)
798 goto dealloc_pd;
799 rc = smc_wr_create_link(lnk);
800 if (rc)
801 goto destroy_qp;
802 lnk->state = SMC_LNK_ACTIVATING;
803 return 0;
804
805destroy_qp:
806 smc_ib_destroy_queue_pair(lnk);
807dealloc_pd:
808 smc_ib_dealloc_protection_domain(lnk);
809free_link_mem:
810 smc_wr_free_link_mem(lnk);
811clear_llc_lnk:
812 smc_llc_link_clear(link: lnk, log: false);
813out:
814 smc_ibdev_cnt_dec(lnk);
815 put_device(dev: &lnk->smcibdev->ibdev->dev);
816 smcibdev = lnk->smcibdev;
817 memset(lnk, 0, sizeof(struct smc_link));
818 lnk->state = SMC_LNK_UNUSED;
819 if (!atomic_dec_return(v: &smcibdev->lnk_cnt))
820 wake_up(&smcibdev->lnks_deleted);
821 smc_lgr_put(lgr); /* lgr_hold above */
822 return rc;
823}
824
825/* create a new SMC link group */
826static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
827{
828 struct smc_link_group *lgr;
829 struct list_head *lgr_list;
830 struct smcd_dev *smcd;
831 struct smc_link *lnk;
832 spinlock_t *lgr_lock;
833 u8 link_idx;
834 int rc = 0;
835 int i;
836
837 if (ini->is_smcd && ini->vlan_id) {
838 if (smc_ism_get_vlan(dev: ini->ism_dev[ini->ism_selected],
839 vlan_id: ini->vlan_id)) {
840 rc = SMC_CLC_DECL_ISMVLANERR;
841 goto out;
842 }
843 }
844
845 lgr = kzalloc(size: sizeof(*lgr), GFP_KERNEL);
846 if (!lgr) {
847 rc = SMC_CLC_DECL_MEM;
848 goto ism_put_vlan;
849 }
850 lgr->tx_wq = alloc_workqueue(fmt: "smc_tx_wq-%*phN", flags: 0, max_active: 0,
851 SMC_LGR_ID_SIZE, &lgr->id);
852 if (!lgr->tx_wq) {
853 rc = -ENOMEM;
854 goto free_lgr;
855 }
856 lgr->is_smcd = ini->is_smcd;
857 lgr->sync_err = 0;
858 lgr->terminating = 0;
859 lgr->freeing = 0;
860 lgr->vlan_id = ini->vlan_id;
861 refcount_set(r: &lgr->refcnt, n: 1); /* set lgr refcnt to 1 */
862 init_rwsem(&lgr->sndbufs_lock);
863 init_rwsem(&lgr->rmbs_lock);
864 rwlock_init(&lgr->conns_lock);
865 for (i = 0; i < SMC_RMBE_SIZES; i++) {
866 INIT_LIST_HEAD(list: &lgr->sndbufs[i]);
867 INIT_LIST_HEAD(list: &lgr->rmbs[i]);
868 }
869 lgr->next_link_id = 0;
870 smc_lgr_list.num += SMC_LGR_NUM_INCR;
871 memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
872 INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
873 INIT_WORK(&lgr->terminate_work, smc_lgr_terminate_work);
874 lgr->conns_all = RB_ROOT;
875 if (ini->is_smcd) {
876 /* SMC-D specific settings */
877 smcd = ini->ism_dev[ini->ism_selected];
878 get_device(dev: smcd->ops->get_dev(smcd));
879 lgr->peer_gid = ini->ism_peer_gid[ini->ism_selected];
880 lgr->smcd = ini->ism_dev[ini->ism_selected];
881 lgr_list = &ini->ism_dev[ini->ism_selected]->lgr_list;
882 lgr_lock = &lgr->smcd->lgr_lock;
883 lgr->smc_version = ini->smcd_version;
884 lgr->peer_shutdown = 0;
885 atomic_inc(v: &ini->ism_dev[ini->ism_selected]->lgr_cnt);
886 } else {
887 /* SMC-R specific settings */
888 struct smc_ib_device *ibdev;
889 int ibport;
890
891 lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
892 lgr->smc_version = ini->smcr_version;
893 memcpy(lgr->peer_systemid, ini->peer_systemid,
894 SMC_SYSTEMID_LEN);
895 if (lgr->smc_version == SMC_V2) {
896 ibdev = ini->smcrv2.ib_dev_v2;
897 ibport = ini->smcrv2.ib_port_v2;
898 lgr->saddr = ini->smcrv2.saddr;
899 lgr->uses_gateway = ini->smcrv2.uses_gateway;
900 memcpy(lgr->nexthop_mac, ini->smcrv2.nexthop_mac,
901 ETH_ALEN);
902 lgr->max_conns = ini->max_conns;
903 lgr->max_links = ini->max_links;
904 } else {
905 ibdev = ini->ib_dev;
906 ibport = ini->ib_port;
907 lgr->max_conns = SMC_CONN_PER_LGR_MAX;
908 lgr->max_links = SMC_LINKS_ADD_LNK_MAX;
909 }
910 memcpy(lgr->pnet_id, ibdev->pnetid[ibport - 1],
911 SMC_MAX_PNETID_LEN);
912 rc = smc_wr_alloc_lgr_mem(lgr);
913 if (rc)
914 goto free_wq;
915 smc_llc_lgr_init(lgr, smc);
916
917 link_idx = SMC_SINGLE_LINK;
918 lnk = &lgr->lnk[link_idx];
919 rc = smcr_link_init(lgr, lnk, link_idx, ini);
920 if (rc) {
921 smc_wr_free_lgr_mem(lgr);
922 goto free_wq;
923 }
924 lgr->net = smc_ib_net(smcibdev: lnk->smcibdev);
925 lgr_list = &smc_lgr_list.list;
926 lgr_lock = &smc_lgr_list.lock;
927 lgr->buf_type = lgr->net->smc.sysctl_smcr_buf_type;
928 atomic_inc(v: &lgr_cnt);
929 }
930 smc->conn.lgr = lgr;
931 spin_lock_bh(lock: lgr_lock);
932 list_add_tail(new: &lgr->list, head: lgr_list);
933 spin_unlock_bh(lock: lgr_lock);
934 return 0;
935
936free_wq:
937 destroy_workqueue(wq: lgr->tx_wq);
938free_lgr:
939 kfree(objp: lgr);
940ism_put_vlan:
941 if (ini->is_smcd && ini->vlan_id)
942 smc_ism_put_vlan(dev: ini->ism_dev[ini->ism_selected], vlan_id: ini->vlan_id);
943out:
944 if (rc < 0) {
945 if (rc == -ENOMEM)
946 rc = SMC_CLC_DECL_MEM;
947 else
948 rc = SMC_CLC_DECL_INTERR;
949 }
950 return rc;
951}
952
953static int smc_write_space(struct smc_connection *conn)
954{
955 int buffer_len = conn->peer_rmbe_size;
956 union smc_host_cursor prod;
957 union smc_host_cursor cons;
958 int space;
959
960 smc_curs_copy(tgt: &prod, src: &conn->local_tx_ctrl.prod, conn);
961 smc_curs_copy(tgt: &cons, src: &conn->local_rx_ctrl.cons, conn);
962 /* determine rx_buf space */
963 space = buffer_len - smc_curs_diff(size: buffer_len, old: &cons, new: &prod);
964 return space;
965}
966
967static int smc_switch_cursor(struct smc_sock *smc, struct smc_cdc_tx_pend *pend,
968 struct smc_wr_buf *wr_buf)
969{
970 struct smc_connection *conn = &smc->conn;
971 union smc_host_cursor cons, fin;
972 int rc = 0;
973 int diff;
974
975 smc_curs_copy(tgt: &conn->tx_curs_sent, src: &conn->tx_curs_fin, conn);
976 smc_curs_copy(tgt: &fin, src: &conn->local_tx_ctrl_fin, conn);
977 /* set prod cursor to old state, enforce tx_rdma_writes() */
978 smc_curs_copy(tgt: &conn->local_tx_ctrl.prod, src: &fin, conn);
979 smc_curs_copy(tgt: &cons, src: &conn->local_rx_ctrl.cons, conn);
980
981 if (smc_curs_comp(size: conn->peer_rmbe_size, old: &cons, new: &fin) < 0) {
982 /* cons cursor advanced more than fin, and prod was set
983 * fin above, so now prod is smaller than cons. Fix that.
984 */
985 diff = smc_curs_diff(size: conn->peer_rmbe_size, old: &fin, new: &cons);
986 smc_curs_add(size: conn->sndbuf_desc->len,
987 curs: &conn->tx_curs_sent, value: diff);
988 smc_curs_add(size: conn->sndbuf_desc->len,
989 curs: &conn->tx_curs_fin, value: diff);
990
991 smp_mb__before_atomic();
992 atomic_add(i: diff, v: &conn->sndbuf_space);
993 smp_mb__after_atomic();
994
995 smc_curs_add(size: conn->peer_rmbe_size,
996 curs: &conn->local_tx_ctrl.prod, value: diff);
997 smc_curs_add(size: conn->peer_rmbe_size,
998 curs: &conn->local_tx_ctrl_fin, value: diff);
999 }
1000 /* recalculate, value is used by tx_rdma_writes() */
1001 atomic_set(v: &smc->conn.peer_rmbe_space, i: smc_write_space(conn));
1002
1003 if (smc->sk.sk_state != SMC_INIT &&
1004 smc->sk.sk_state != SMC_CLOSED) {
1005 rc = smcr_cdc_msg_send_validation(conn, pend, wr_buf);
1006 if (!rc) {
1007 queue_delayed_work(wq: conn->lgr->tx_wq, dwork: &conn->tx_work, delay: 0);
1008 smc->sk.sk_data_ready(&smc->sk);
1009 }
1010 } else {
1011 smc_wr_tx_put_slot(link: conn->lnk,
1012 wr_pend_priv: (struct smc_wr_tx_pend_priv *)pend);
1013 }
1014 return rc;
1015}
1016
1017void smc_switch_link_and_count(struct smc_connection *conn,
1018 struct smc_link *to_lnk)
1019{
1020 atomic_dec(v: &conn->lnk->conn_cnt);
1021 /* link_hold in smc_conn_create() */
1022 smcr_link_put(lnk: conn->lnk);
1023 conn->lnk = to_lnk;
1024 atomic_inc(v: &conn->lnk->conn_cnt);
1025 /* link_put in smc_conn_free() */
1026 smcr_link_hold(lnk: conn->lnk);
1027}
1028
1029struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
1030 struct smc_link *from_lnk, bool is_dev_err)
1031{
1032 struct smc_link *to_lnk = NULL;
1033 struct smc_cdc_tx_pend *pend;
1034 struct smc_connection *conn;
1035 struct smc_wr_buf *wr_buf;
1036 struct smc_sock *smc;
1037 struct rb_node *node;
1038 int i, rc = 0;
1039
1040 /* link is inactive, wake up tx waiters */
1041 smc_wr_wakeup_tx_wait(lnk: from_lnk);
1042
1043 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1044 if (!smc_link_active(lnk: &lgr->lnk[i]) || i == from_lnk->link_idx)
1045 continue;
1046 if (is_dev_err && from_lnk->smcibdev == lgr->lnk[i].smcibdev &&
1047 from_lnk->ibport == lgr->lnk[i].ibport) {
1048 continue;
1049 }
1050 to_lnk = &lgr->lnk[i];
1051 break;
1052 }
1053 if (!to_lnk || !smc_wr_tx_link_hold(link: to_lnk)) {
1054 smc_lgr_terminate_sched(lgr);
1055 return NULL;
1056 }
1057again:
1058 read_lock_bh(&lgr->conns_lock);
1059 for (node = rb_first(&lgr->conns_all); node; node = rb_next(node)) {
1060 conn = rb_entry(node, struct smc_connection, alert_node);
1061 if (conn->lnk != from_lnk)
1062 continue;
1063 smc = container_of(conn, struct smc_sock, conn);
1064 /* conn->lnk not yet set in SMC_INIT state */
1065 if (smc->sk.sk_state == SMC_INIT)
1066 continue;
1067 if (smc->sk.sk_state == SMC_CLOSED ||
1068 smc->sk.sk_state == SMC_PEERCLOSEWAIT1 ||
1069 smc->sk.sk_state == SMC_PEERCLOSEWAIT2 ||
1070 smc->sk.sk_state == SMC_APPFINCLOSEWAIT ||
1071 smc->sk.sk_state == SMC_APPCLOSEWAIT1 ||
1072 smc->sk.sk_state == SMC_APPCLOSEWAIT2 ||
1073 smc->sk.sk_state == SMC_PEERFINCLOSEWAIT ||
1074 smc->sk.sk_state == SMC_PEERABORTWAIT ||
1075 smc->sk.sk_state == SMC_PROCESSABORT) {
1076 spin_lock_bh(lock: &conn->send_lock);
1077 smc_switch_link_and_count(conn, to_lnk);
1078 spin_unlock_bh(lock: &conn->send_lock);
1079 continue;
1080 }
1081 sock_hold(sk: &smc->sk);
1082 read_unlock_bh(&lgr->conns_lock);
1083 /* pre-fetch buffer outside of send_lock, might sleep */
1084 rc = smc_cdc_get_free_slot(conn, link: to_lnk, wr_buf: &wr_buf, NULL, pend: &pend);
1085 if (rc)
1086 goto err_out;
1087 /* avoid race with smcr_tx_sndbuf_nonempty() */
1088 spin_lock_bh(lock: &conn->send_lock);
1089 smc_switch_link_and_count(conn, to_lnk);
1090 rc = smc_switch_cursor(smc, pend, wr_buf);
1091 spin_unlock_bh(lock: &conn->send_lock);
1092 sock_put(sk: &smc->sk);
1093 if (rc)
1094 goto err_out;
1095 goto again;
1096 }
1097 read_unlock_bh(&lgr->conns_lock);
1098 smc_wr_tx_link_put(link: to_lnk);
1099 return to_lnk;
1100
1101err_out:
1102 smcr_link_down_cond_sched(lnk: to_lnk);
1103 smc_wr_tx_link_put(link: to_lnk);
1104 return NULL;
1105}
1106
1107static void smcr_buf_unuse(struct smc_buf_desc *buf_desc, bool is_rmb,
1108 struct smc_link_group *lgr)
1109{
1110 struct rw_semaphore *lock; /* lock buffer list */
1111 int rc;
1112
1113 if (is_rmb && buf_desc->is_conf_rkey && !list_empty(head: &lgr->list)) {
1114 /* unregister rmb with peer */
1115 rc = smc_llc_flow_initiate(lgr, type: SMC_LLC_FLOW_RKEY);
1116 if (!rc) {
1117 /* protect against smc_llc_cli_rkey_exchange() */
1118 down_read(sem: &lgr->llc_conf_mutex);
1119 smc_llc_do_delete_rkey(lgr, rmb_desc: buf_desc);
1120 buf_desc->is_conf_rkey = false;
1121 up_read(sem: &lgr->llc_conf_mutex);
1122 smc_llc_flow_stop(lgr, flow: &lgr->llc_flow_lcl);
1123 }
1124 }
1125
1126 if (buf_desc->is_reg_err) {
1127 /* buf registration failed, reuse not possible */
1128 lock = is_rmb ? &lgr->rmbs_lock :
1129 &lgr->sndbufs_lock;
1130 down_write(sem: lock);
1131 list_del(entry: &buf_desc->list);
1132 up_write(sem: lock);
1133
1134 smc_buf_free(lgr, is_rmb, buf_desc);
1135 } else {
1136 /* memzero_explicit provides potential memory barrier semantics */
1137 memzero_explicit(s: buf_desc->cpu_addr, count: buf_desc->len);
1138 WRITE_ONCE(buf_desc->used, 0);
1139 }
1140}
1141
1142static void smc_buf_unuse(struct smc_connection *conn,
1143 struct smc_link_group *lgr)
1144{
1145 if (conn->sndbuf_desc) {
1146 if (!lgr->is_smcd && conn->sndbuf_desc->is_vm) {
1147 smcr_buf_unuse(buf_desc: conn->sndbuf_desc, is_rmb: false, lgr);
1148 } else {
1149 memzero_explicit(s: conn->sndbuf_desc->cpu_addr, count: conn->sndbuf_desc->len);
1150 WRITE_ONCE(conn->sndbuf_desc->used, 0);
1151 }
1152 }
1153 if (conn->rmb_desc) {
1154 if (!lgr->is_smcd) {
1155 smcr_buf_unuse(buf_desc: conn->rmb_desc, is_rmb: true, lgr);
1156 } else {
1157 memzero_explicit(s: conn->rmb_desc->cpu_addr,
1158 count: conn->rmb_desc->len + sizeof(struct smcd_cdc_msg));
1159 WRITE_ONCE(conn->rmb_desc->used, 0);
1160 }
1161 }
1162}
1163
1164/* remove a finished connection from its link group */
1165void smc_conn_free(struct smc_connection *conn)
1166{
1167 struct smc_link_group *lgr = conn->lgr;
1168
1169 if (!lgr || conn->freed)
1170 /* Connection has never been registered in a
1171 * link group, or has already been freed.
1172 */
1173 return;
1174
1175 conn->freed = 1;
1176 if (!smc_conn_lgr_valid(conn))
1177 /* Connection has already unregistered from
1178 * link group.
1179 */
1180 goto lgr_put;
1181
1182 if (lgr->is_smcd) {
1183 if (!list_empty(head: &lgr->list))
1184 smc_ism_unset_conn(conn);
1185 tasklet_kill(t: &conn->rx_tsklet);
1186 } else {
1187 smc_cdc_wait_pend_tx_wr(conn);
1188 if (current_work() != &conn->abort_work)
1189 cancel_work_sync(work: &conn->abort_work);
1190 }
1191 if (!list_empty(head: &lgr->list)) {
1192 smc_buf_unuse(conn, lgr); /* allow buffer reuse */
1193 smc_lgr_unregister_conn(conn);
1194 }
1195
1196 if (!lgr->conns_num)
1197 smc_lgr_schedule_free_work(lgr);
1198lgr_put:
1199 if (!lgr->is_smcd)
1200 smcr_link_put(lnk: conn->lnk); /* link_hold in smc_conn_create() */
1201 smc_lgr_put(lgr); /* lgr_hold in smc_conn_create() */
1202}
1203
1204/* unregister a link from a buf_desc */
1205static void smcr_buf_unmap_link(struct smc_buf_desc *buf_desc, bool is_rmb,
1206 struct smc_link *lnk)
1207{
1208 if (is_rmb || buf_desc->is_vm)
1209 buf_desc->is_reg_mr[lnk->link_idx] = false;
1210 if (!buf_desc->is_map_ib[lnk->link_idx])
1211 return;
1212
1213 if ((is_rmb || buf_desc->is_vm) &&
1214 buf_desc->mr[lnk->link_idx]) {
1215 smc_ib_put_memory_region(mr: buf_desc->mr[lnk->link_idx]);
1216 buf_desc->mr[lnk->link_idx] = NULL;
1217 }
1218 if (is_rmb)
1219 smc_ib_buf_unmap_sg(lnk, buf_slot: buf_desc, data_direction: DMA_FROM_DEVICE);
1220 else
1221 smc_ib_buf_unmap_sg(lnk, buf_slot: buf_desc, data_direction: DMA_TO_DEVICE);
1222
1223 sg_free_table(&buf_desc->sgt[lnk->link_idx]);
1224 buf_desc->is_map_ib[lnk->link_idx] = false;
1225}
1226
1227/* unmap all buffers of lgr for a deleted link */
1228static void smcr_buf_unmap_lgr(struct smc_link *lnk)
1229{
1230 struct smc_link_group *lgr = lnk->lgr;
1231 struct smc_buf_desc *buf_desc, *bf;
1232 int i;
1233
1234 for (i = 0; i < SMC_RMBE_SIZES; i++) {
1235 down_write(sem: &lgr->rmbs_lock);
1236 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list)
1237 smcr_buf_unmap_link(buf_desc, is_rmb: true, lnk);
1238 up_write(sem: &lgr->rmbs_lock);
1239
1240 down_write(sem: &lgr->sndbufs_lock);
1241 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i],
1242 list)
1243 smcr_buf_unmap_link(buf_desc, is_rmb: false, lnk);
1244 up_write(sem: &lgr->sndbufs_lock);
1245 }
1246}
1247
1248static void smcr_rtoken_clear_link(struct smc_link *lnk)
1249{
1250 struct smc_link_group *lgr = lnk->lgr;
1251 int i;
1252
1253 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
1254 lgr->rtokens[i][lnk->link_idx].rkey = 0;
1255 lgr->rtokens[i][lnk->link_idx].dma_addr = 0;
1256 }
1257}
1258
1259static void __smcr_link_clear(struct smc_link *lnk)
1260{
1261 struct smc_link_group *lgr = lnk->lgr;
1262 struct smc_ib_device *smcibdev;
1263
1264 smc_wr_free_link_mem(lnk);
1265 smc_ibdev_cnt_dec(lnk);
1266 put_device(dev: &lnk->smcibdev->ibdev->dev);
1267 smcibdev = lnk->smcibdev;
1268 memset(lnk, 0, sizeof(struct smc_link));
1269 lnk->state = SMC_LNK_UNUSED;
1270 if (!atomic_dec_return(v: &smcibdev->lnk_cnt))
1271 wake_up(&smcibdev->lnks_deleted);
1272 smc_lgr_put(lgr); /* lgr_hold in smcr_link_init() */
1273}
1274
1275/* must be called under lgr->llc_conf_mutex lock */
1276void smcr_link_clear(struct smc_link *lnk, bool log)
1277{
1278 if (!lnk->lgr || lnk->clearing ||
1279 lnk->state == SMC_LNK_UNUSED)
1280 return;
1281 lnk->clearing = 1;
1282 lnk->peer_qpn = 0;
1283 smc_llc_link_clear(link: lnk, log);
1284 smcr_buf_unmap_lgr(lnk);
1285 smcr_rtoken_clear_link(lnk);
1286 smc_ib_modify_qp_error(lnk);
1287 smc_wr_free_link(lnk);
1288 smc_ib_destroy_queue_pair(lnk);
1289 smc_ib_dealloc_protection_domain(lnk);
1290 smcr_link_put(lnk); /* theoretically last link_put */
1291}
1292
1293void smcr_link_hold(struct smc_link *lnk)
1294{
1295 refcount_inc(r: &lnk->refcnt);
1296}
1297
1298void smcr_link_put(struct smc_link *lnk)
1299{
1300 if (refcount_dec_and_test(r: &lnk->refcnt))
1301 __smcr_link_clear(lnk);
1302}
1303
1304static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
1305 struct smc_buf_desc *buf_desc)
1306{
1307 int i;
1308
1309 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1310 smcr_buf_unmap_link(buf_desc, is_rmb, lnk: &lgr->lnk[i]);
1311
1312 if (!buf_desc->is_vm && buf_desc->pages)
1313 __free_pages(page: buf_desc->pages, order: buf_desc->order);
1314 else if (buf_desc->is_vm && buf_desc->cpu_addr)
1315 vfree(addr: buf_desc->cpu_addr);
1316 kfree(objp: buf_desc);
1317}
1318
1319static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
1320 struct smc_buf_desc *buf_desc)
1321{
1322 if (is_dmb) {
1323 /* restore original buf len */
1324 buf_desc->len += sizeof(struct smcd_cdc_msg);
1325 smc_ism_unregister_dmb(dev: lgr->smcd, dmb_desc: buf_desc);
1326 } else {
1327 kfree(objp: buf_desc->cpu_addr);
1328 }
1329 kfree(objp: buf_desc);
1330}
1331
1332static void smc_buf_free(struct smc_link_group *lgr, bool is_rmb,
1333 struct smc_buf_desc *buf_desc)
1334{
1335 if (lgr->is_smcd)
1336 smcd_buf_free(lgr, is_dmb: is_rmb, buf_desc);
1337 else
1338 smcr_buf_free(lgr, is_rmb, buf_desc);
1339}
1340
1341static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb)
1342{
1343 struct smc_buf_desc *buf_desc, *bf_desc;
1344 struct list_head *buf_list;
1345 int i;
1346
1347 for (i = 0; i < SMC_RMBE_SIZES; i++) {
1348 if (is_rmb)
1349 buf_list = &lgr->rmbs[i];
1350 else
1351 buf_list = &lgr->sndbufs[i];
1352 list_for_each_entry_safe(buf_desc, bf_desc, buf_list,
1353 list) {
1354 list_del(entry: &buf_desc->list);
1355 smc_buf_free(lgr, is_rmb, buf_desc);
1356 }
1357 }
1358}
1359
1360static void smc_lgr_free_bufs(struct smc_link_group *lgr)
1361{
1362 /* free send buffers */
1363 __smc_lgr_free_bufs(lgr, is_rmb: false);
1364 /* free rmbs */
1365 __smc_lgr_free_bufs(lgr, is_rmb: true);
1366}
1367
1368/* won't be freed until no one accesses to lgr anymore */
1369static void __smc_lgr_free(struct smc_link_group *lgr)
1370{
1371 smc_lgr_free_bufs(lgr);
1372 if (lgr->is_smcd) {
1373 if (!atomic_dec_return(v: &lgr->smcd->lgr_cnt))
1374 wake_up(&lgr->smcd->lgrs_deleted);
1375 } else {
1376 smc_wr_free_lgr_mem(lgr);
1377 if (!atomic_dec_return(v: &lgr_cnt))
1378 wake_up(&lgrs_deleted);
1379 }
1380 kfree(objp: lgr);
1381}
1382
1383/* remove a link group */
1384static void smc_lgr_free(struct smc_link_group *lgr)
1385{
1386 int i;
1387
1388 if (!lgr->is_smcd) {
1389 down_write(sem: &lgr->llc_conf_mutex);
1390 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1391 if (lgr->lnk[i].state != SMC_LNK_UNUSED)
1392 smcr_link_clear(lnk: &lgr->lnk[i], log: false);
1393 }
1394 up_write(sem: &lgr->llc_conf_mutex);
1395 smc_llc_lgr_clear(lgr);
1396 }
1397
1398 destroy_workqueue(wq: lgr->tx_wq);
1399 if (lgr->is_smcd) {
1400 smc_ism_put_vlan(dev: lgr->smcd, vlan_id: lgr->vlan_id);
1401 put_device(dev: lgr->smcd->ops->get_dev(lgr->smcd));
1402 }
1403 smc_lgr_put(lgr); /* theoretically last lgr_put */
1404}
1405
1406void smc_lgr_hold(struct smc_link_group *lgr)
1407{
1408 refcount_inc(r: &lgr->refcnt);
1409}
1410
1411void smc_lgr_put(struct smc_link_group *lgr)
1412{
1413 if (refcount_dec_and_test(r: &lgr->refcnt))
1414 __smc_lgr_free(lgr);
1415}
1416
1417static void smc_sk_wake_ups(struct smc_sock *smc)
1418{
1419 smc->sk.sk_write_space(&smc->sk);
1420 smc->sk.sk_data_ready(&smc->sk);
1421 smc->sk.sk_state_change(&smc->sk);
1422}
1423
1424/* kill a connection */
1425static void smc_conn_kill(struct smc_connection *conn, bool soft)
1426{
1427 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1428
1429 if (conn->lgr->is_smcd && conn->lgr->peer_shutdown)
1430 conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
1431 else
1432 smc_close_abort(conn);
1433 conn->killed = 1;
1434 smc->sk.sk_err = ECONNABORTED;
1435 smc_sk_wake_ups(smc);
1436 if (conn->lgr->is_smcd) {
1437 smc_ism_unset_conn(conn);
1438 if (soft)
1439 tasklet_kill(t: &conn->rx_tsklet);
1440 else
1441 tasklet_unlock_wait(t: &conn->rx_tsklet);
1442 } else {
1443 smc_cdc_wait_pend_tx_wr(conn);
1444 }
1445 smc_lgr_unregister_conn(conn);
1446 smc_close_active_abort(smc);
1447}
1448
1449static void smc_lgr_cleanup(struct smc_link_group *lgr)
1450{
1451 if (lgr->is_smcd) {
1452 smc_ism_signal_shutdown(lgr);
1453 } else {
1454 u32 rsn = lgr->llc_termination_rsn;
1455
1456 if (!rsn)
1457 rsn = SMC_LLC_DEL_PROG_INIT_TERM;
1458 smc_llc_send_link_delete_all(lgr, ord: false, rsn);
1459 smcr_lgr_link_deactivate_all(lgr);
1460 }
1461}
1462
1463/* terminate link group
1464 * @soft: true if link group shutdown can take its time
1465 * false if immediate link group shutdown is required
1466 */
1467static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
1468{
1469 struct smc_connection *conn;
1470 struct smc_sock *smc;
1471 struct rb_node *node;
1472
1473 if (lgr->terminating)
1474 return; /* lgr already terminating */
1475 /* cancel free_work sync, will terminate when lgr->freeing is set */
1476 cancel_delayed_work(dwork: &lgr->free_work);
1477 lgr->terminating = 1;
1478
1479 /* kill remaining link group connections */
1480 read_lock_bh(&lgr->conns_lock);
1481 node = rb_first(&lgr->conns_all);
1482 while (node) {
1483 read_unlock_bh(&lgr->conns_lock);
1484 conn = rb_entry(node, struct smc_connection, alert_node);
1485 smc = container_of(conn, struct smc_sock, conn);
1486 sock_hold(sk: &smc->sk); /* sock_put below */
1487 lock_sock(sk: &smc->sk);
1488 smc_conn_kill(conn, soft);
1489 release_sock(sk: &smc->sk);
1490 sock_put(sk: &smc->sk); /* sock_hold above */
1491 read_lock_bh(&lgr->conns_lock);
1492 node = rb_first(&lgr->conns_all);
1493 }
1494 read_unlock_bh(&lgr->conns_lock);
1495 smc_lgr_cleanup(lgr);
1496 smc_lgr_free(lgr);
1497}
1498
1499/* unlink link group and schedule termination */
1500void smc_lgr_terminate_sched(struct smc_link_group *lgr)
1501{
1502 spinlock_t *lgr_lock;
1503
1504 smc_lgr_list_head(lgr, lgr_lock: &lgr_lock);
1505 spin_lock_bh(lock: lgr_lock);
1506 if (list_empty(head: &lgr->list) || lgr->terminating || lgr->freeing) {
1507 spin_unlock_bh(lock: lgr_lock);
1508 return; /* lgr already terminating */
1509 }
1510 list_del_init(entry: &lgr->list);
1511 lgr->freeing = 1;
1512 spin_unlock_bh(lock: lgr_lock);
1513 schedule_work(work: &lgr->terminate_work);
1514}
1515
1516/* Called when peer lgr shutdown (regularly or abnormally) is received */
1517void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
1518{
1519 struct smc_link_group *lgr, *l;
1520 LIST_HEAD(lgr_free_list);
1521
1522 /* run common cleanup function and build free list */
1523 spin_lock_bh(lock: &dev->lgr_lock);
1524 list_for_each_entry_safe(lgr, l, &dev->lgr_list, list) {
1525 if ((!peer_gid || lgr->peer_gid == peer_gid) &&
1526 (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
1527 if (peer_gid) /* peer triggered termination */
1528 lgr->peer_shutdown = 1;
1529 list_move(list: &lgr->list, head: &lgr_free_list);
1530 lgr->freeing = 1;
1531 }
1532 }
1533 spin_unlock_bh(lock: &dev->lgr_lock);
1534
1535 /* cancel the regular free workers and actually free lgrs */
1536 list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
1537 list_del_init(entry: &lgr->list);
1538 schedule_work(work: &lgr->terminate_work);
1539 }
1540}
1541
1542/* Called when an SMCD device is removed or the smc module is unloaded */
1543void smc_smcd_terminate_all(struct smcd_dev *smcd)
1544{
1545 struct smc_link_group *lgr, *lg;
1546 LIST_HEAD(lgr_free_list);
1547
1548 spin_lock_bh(lock: &smcd->lgr_lock);
1549 list_splice_init(list: &smcd->lgr_list, head: &lgr_free_list);
1550 list_for_each_entry(lgr, &lgr_free_list, list)
1551 lgr->freeing = 1;
1552 spin_unlock_bh(lock: &smcd->lgr_lock);
1553
1554 list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1555 list_del_init(entry: &lgr->list);
1556 __smc_lgr_terminate(lgr, soft: false);
1557 }
1558
1559 if (atomic_read(v: &smcd->lgr_cnt))
1560 wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
1561}
1562
1563/* Called when an SMCR device is removed or the smc module is unloaded.
1564 * If smcibdev is given, all SMCR link groups using this device are terminated.
1565 * If smcibdev is NULL, all SMCR link groups are terminated.
1566 */
1567void smc_smcr_terminate_all(struct smc_ib_device *smcibdev)
1568{
1569 struct smc_link_group *lgr, *lg;
1570 LIST_HEAD(lgr_free_list);
1571 int i;
1572
1573 spin_lock_bh(lock: &smc_lgr_list.lock);
1574 if (!smcibdev) {
1575 list_splice_init(list: &smc_lgr_list.list, head: &lgr_free_list);
1576 list_for_each_entry(lgr, &lgr_free_list, list)
1577 lgr->freeing = 1;
1578 } else {
1579 list_for_each_entry_safe(lgr, lg, &smc_lgr_list.list, list) {
1580 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1581 if (lgr->lnk[i].smcibdev == smcibdev)
1582 smcr_link_down_cond_sched(lnk: &lgr->lnk[i]);
1583 }
1584 }
1585 }
1586 spin_unlock_bh(lock: &smc_lgr_list.lock);
1587
1588 list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
1589 list_del_init(entry: &lgr->list);
1590 smc_llc_set_termination_rsn(lgr, SMC_LLC_DEL_OP_INIT_TERM);
1591 __smc_lgr_terminate(lgr, soft: false);
1592 }
1593
1594 if (smcibdev) {
1595 if (atomic_read(v: &smcibdev->lnk_cnt))
1596 wait_event(smcibdev->lnks_deleted,
1597 !atomic_read(&smcibdev->lnk_cnt));
1598 } else {
1599 if (atomic_read(v: &lgr_cnt))
1600 wait_event(lgrs_deleted, !atomic_read(&lgr_cnt));
1601 }
1602}
1603
1604/* set new lgr type and clear all asymmetric link tagging */
1605void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type)
1606{
1607 char *lgr_type = "";
1608 int i;
1609
1610 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++)
1611 if (smc_link_usable(lnk: &lgr->lnk[i]))
1612 lgr->lnk[i].link_is_asym = false;
1613 if (lgr->type == new_type)
1614 return;
1615 lgr->type = new_type;
1616
1617 switch (lgr->type) {
1618 case SMC_LGR_NONE:
1619 lgr_type = "NONE";
1620 break;
1621 case SMC_LGR_SINGLE:
1622 lgr_type = "SINGLE";
1623 break;
1624 case SMC_LGR_SYMMETRIC:
1625 lgr_type = "SYMMETRIC";
1626 break;
1627 case SMC_LGR_ASYMMETRIC_PEER:
1628 lgr_type = "ASYMMETRIC_PEER";
1629 break;
1630 case SMC_LGR_ASYMMETRIC_LOCAL:
1631 lgr_type = "ASYMMETRIC_LOCAL";
1632 break;
1633 }
1634 pr_warn_ratelimited("smc: SMC-R lg %*phN net %llu state changed: "
1635 "%s, pnetid %.16s\n", SMC_LGR_ID_SIZE, &lgr->id,
1636 lgr->net->net_cookie, lgr_type, lgr->pnet_id);
1637}
1638
1639/* set new lgr type and tag a link as asymmetric */
1640void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
1641 enum smc_lgr_type new_type, int asym_lnk_idx)
1642{
1643 smcr_lgr_set_type(lgr, new_type);
1644 lgr->lnk[asym_lnk_idx].link_is_asym = true;
1645}
1646
1647/* abort connection, abort_work scheduled from tasklet context */
1648static void smc_conn_abort_work(struct work_struct *work)
1649{
1650 struct smc_connection *conn = container_of(work,
1651 struct smc_connection,
1652 abort_work);
1653 struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
1654
1655 lock_sock(sk: &smc->sk);
1656 smc_conn_kill(conn, soft: true);
1657 release_sock(sk: &smc->sk);
1658 sock_put(sk: &smc->sk); /* sock_hold done by schedulers of abort_work */
1659}
1660
1661void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport)
1662{
1663 struct smc_link_group *lgr, *n;
1664
1665 spin_lock_bh(lock: &smc_lgr_list.lock);
1666 list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1667 struct smc_link *link;
1668
1669 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1670 SMC_MAX_PNETID_LEN) ||
1671 lgr->type == SMC_LGR_SYMMETRIC ||
1672 lgr->type == SMC_LGR_ASYMMETRIC_PEER ||
1673 !rdma_dev_access_netns(device: smcibdev->ibdev, net: lgr->net))
1674 continue;
1675
1676 if (lgr->type == SMC_LGR_SINGLE && lgr->max_links <= 1)
1677 continue;
1678
1679 /* trigger local add link processing */
1680 link = smc_llc_usable_link(lgr);
1681 if (link)
1682 smc_llc_add_link_local(link);
1683 }
1684 spin_unlock_bh(lock: &smc_lgr_list.lock);
1685}
1686
1687/* link is down - switch connections to alternate link,
1688 * must be called under lgr->llc_conf_mutex lock
1689 */
1690static void smcr_link_down(struct smc_link *lnk)
1691{
1692 struct smc_link_group *lgr = lnk->lgr;
1693 struct smc_link *to_lnk;
1694 int del_link_id;
1695
1696 if (!lgr || lnk->state == SMC_LNK_UNUSED || list_empty(head: &lgr->list))
1697 return;
1698
1699 to_lnk = smc_switch_conns(lgr, from_lnk: lnk, is_dev_err: true);
1700 if (!to_lnk) { /* no backup link available */
1701 smcr_link_clear(lnk, log: true);
1702 return;
1703 }
1704 smcr_lgr_set_type(lgr, new_type: SMC_LGR_SINGLE);
1705 del_link_id = lnk->link_id;
1706
1707 if (lgr->role == SMC_SERV) {
1708 /* trigger local delete link processing */
1709 smc_llc_srv_delete_link_local(link: to_lnk, del_link_id);
1710 } else {
1711 if (lgr->llc_flow_lcl.type != SMC_LLC_FLOW_NONE) {
1712 /* another llc task is ongoing */
1713 up_write(sem: &lgr->llc_conf_mutex);
1714 wait_event_timeout(lgr->llc_flow_waiter,
1715 (list_empty(&lgr->list) ||
1716 lgr->llc_flow_lcl.type == SMC_LLC_FLOW_NONE),
1717 SMC_LLC_WAIT_TIME);
1718 down_write(sem: &lgr->llc_conf_mutex);
1719 }
1720 if (!list_empty(head: &lgr->list)) {
1721 smc_llc_send_delete_link(link: to_lnk, link_del_id: del_link_id,
1722 reqresp: SMC_LLC_REQ, orderly: true,
1723 SMC_LLC_DEL_LOST_PATH);
1724 smcr_link_clear(lnk, log: true);
1725 }
1726 wake_up(&lgr->llc_flow_waiter); /* wake up next waiter */
1727 }
1728}
1729
1730/* must be called under lgr->llc_conf_mutex lock */
1731void smcr_link_down_cond(struct smc_link *lnk)
1732{
1733 if (smc_link_downing(&lnk->state)) {
1734 trace_smcr_link_down(lnk, location: __builtin_return_address(0));
1735 smcr_link_down(lnk);
1736 }
1737}
1738
1739/* will get the lgr->llc_conf_mutex lock */
1740void smcr_link_down_cond_sched(struct smc_link *lnk)
1741{
1742 if (smc_link_downing(&lnk->state)) {
1743 trace_smcr_link_down(lnk, location: __builtin_return_address(0));
1744 schedule_work(work: &lnk->link_down_wrk);
1745 }
1746}
1747
1748void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport)
1749{
1750 struct smc_link_group *lgr, *n;
1751 int i;
1752
1753 list_for_each_entry_safe(lgr, n, &smc_lgr_list.list, list) {
1754 if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
1755 SMC_MAX_PNETID_LEN))
1756 continue; /* lgr is not affected */
1757 if (list_empty(head: &lgr->list))
1758 continue;
1759 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1760 struct smc_link *lnk = &lgr->lnk[i];
1761
1762 if (smc_link_usable(lnk) &&
1763 lnk->smcibdev == smcibdev && lnk->ibport == ibport)
1764 smcr_link_down_cond_sched(lnk);
1765 }
1766 }
1767}
1768
1769static void smc_link_down_work(struct work_struct *work)
1770{
1771 struct smc_link *link = container_of(work, struct smc_link,
1772 link_down_wrk);
1773 struct smc_link_group *lgr = link->lgr;
1774
1775 if (list_empty(head: &lgr->list))
1776 return;
1777 wake_up_all(&lgr->llc_msg_waiter);
1778 down_write(sem: &lgr->llc_conf_mutex);
1779 smcr_link_down(lnk: link);
1780 up_write(sem: &lgr->llc_conf_mutex);
1781}
1782
1783static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev,
1784 struct netdev_nested_priv *priv)
1785{
1786 unsigned short *vlan_id = (unsigned short *)priv->data;
1787
1788 if (is_vlan_dev(dev: lower_dev)) {
1789 *vlan_id = vlan_dev_vlan_id(dev: lower_dev);
1790 return 1;
1791 }
1792
1793 return 0;
1794}
1795
1796/* Determine vlan of internal TCP socket. */
1797int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini)
1798{
1799 struct dst_entry *dst = sk_dst_get(sk: clcsock->sk);
1800 struct netdev_nested_priv priv;
1801 struct net_device *ndev;
1802 int rc = 0;
1803
1804 ini->vlan_id = 0;
1805 if (!dst) {
1806 rc = -ENOTCONN;
1807 goto out;
1808 }
1809 if (!dst->dev) {
1810 rc = -ENODEV;
1811 goto out_rel;
1812 }
1813
1814 ndev = dst->dev;
1815 if (is_vlan_dev(dev: ndev)) {
1816 ini->vlan_id = vlan_dev_vlan_id(dev: ndev);
1817 goto out_rel;
1818 }
1819
1820 priv.data = (void *)&ini->vlan_id;
1821 rtnl_lock();
1822 netdev_walk_all_lower_dev(dev: ndev, fn: smc_vlan_by_tcpsk_walk, priv: &priv);
1823 rtnl_unlock();
1824
1825out_rel:
1826 dst_release(dst);
1827out:
1828 return rc;
1829}
1830
1831static bool smcr_lgr_match(struct smc_link_group *lgr, u8 smcr_version,
1832 u8 peer_systemid[],
1833 u8 peer_gid[],
1834 u8 peer_mac_v1[],
1835 enum smc_lgr_role role, u32 clcqpn,
1836 struct net *net)
1837{
1838 struct smc_link *lnk;
1839 int i;
1840
1841 if (memcmp(p: lgr->peer_systemid, q: peer_systemid, SMC_SYSTEMID_LEN) ||
1842 lgr->role != role)
1843 return false;
1844
1845 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
1846 lnk = &lgr->lnk[i];
1847
1848 if (!smc_link_active(lnk))
1849 continue;
1850 /* use verbs API to check netns, instead of lgr->net */
1851 if (!rdma_dev_access_netns(device: lnk->smcibdev->ibdev, net))
1852 return false;
1853 if ((lgr->role == SMC_SERV || lnk->peer_qpn == clcqpn) &&
1854 !memcmp(p: lnk->peer_gid, q: peer_gid, SMC_GID_SIZE) &&
1855 (smcr_version == SMC_V2 ||
1856 !memcmp(p: lnk->peer_mac, q: peer_mac_v1, ETH_ALEN)))
1857 return true;
1858 }
1859 return false;
1860}
1861
1862static bool smcd_lgr_match(struct smc_link_group *lgr,
1863 struct smcd_dev *smcismdev, u64 peer_gid)
1864{
1865 return lgr->peer_gid == peer_gid && lgr->smcd == smcismdev;
1866}
1867
1868/* create a new SMC connection (and a new link group if necessary) */
1869int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini)
1870{
1871 struct smc_connection *conn = &smc->conn;
1872 struct net *net = sock_net(sk: &smc->sk);
1873 struct list_head *lgr_list;
1874 struct smc_link_group *lgr;
1875 enum smc_lgr_role role;
1876 spinlock_t *lgr_lock;
1877 int rc = 0;
1878
1879 lgr_list = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_list :
1880 &smc_lgr_list.list;
1881 lgr_lock = ini->is_smcd ? &ini->ism_dev[ini->ism_selected]->lgr_lock :
1882 &smc_lgr_list.lock;
1883 ini->first_contact_local = 1;
1884 role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
1885 if (role == SMC_CLNT && ini->first_contact_peer)
1886 /* create new link group as well */
1887 goto create;
1888
1889 /* determine if an existing link group can be reused */
1890 spin_lock_bh(lock: lgr_lock);
1891 list_for_each_entry(lgr, lgr_list, list) {
1892 write_lock_bh(&lgr->conns_lock);
1893 if ((ini->is_smcd ?
1894 smcd_lgr_match(lgr, smcismdev: ini->ism_dev[ini->ism_selected],
1895 peer_gid: ini->ism_peer_gid[ini->ism_selected]) :
1896 smcr_lgr_match(lgr, smcr_version: ini->smcr_version,
1897 peer_systemid: ini->peer_systemid,
1898 peer_gid: ini->peer_gid, peer_mac_v1: ini->peer_mac, role,
1899 clcqpn: ini->ib_clcqpn, net)) &&
1900 !lgr->sync_err &&
1901 (ini->smcd_version == SMC_V2 ||
1902 lgr->vlan_id == ini->vlan_id) &&
1903 (role == SMC_CLNT || ini->is_smcd ||
1904 (lgr->conns_num < lgr->max_conns &&
1905 !bitmap_full(src: lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX)))) {
1906 /* link group found */
1907 ini->first_contact_local = 0;
1908 conn->lgr = lgr;
1909 rc = smc_lgr_register_conn(conn, first: false);
1910 write_unlock_bh(&lgr->conns_lock);
1911 if (!rc && delayed_work_pending(&lgr->free_work))
1912 cancel_delayed_work(dwork: &lgr->free_work);
1913 break;
1914 }
1915 write_unlock_bh(&lgr->conns_lock);
1916 }
1917 spin_unlock_bh(lock: lgr_lock);
1918 if (rc)
1919 return rc;
1920
1921 if (role == SMC_CLNT && !ini->first_contact_peer &&
1922 ini->first_contact_local) {
1923 /* Server reuses a link group, but Client wants to start
1924 * a new one
1925 * send out_of_sync decline, reason synchr. error
1926 */
1927 return SMC_CLC_DECL_SYNCERR;
1928 }
1929
1930create:
1931 if (ini->first_contact_local) {
1932 rc = smc_lgr_create(smc, ini);
1933 if (rc)
1934 goto out;
1935 lgr = conn->lgr;
1936 write_lock_bh(&lgr->conns_lock);
1937 rc = smc_lgr_register_conn(conn, first: true);
1938 write_unlock_bh(&lgr->conns_lock);
1939 if (rc) {
1940 smc_lgr_cleanup_early(lgr);
1941 goto out;
1942 }
1943 }
1944 smc_lgr_hold(lgr: conn->lgr); /* lgr_put in smc_conn_free() */
1945 if (!conn->lgr->is_smcd)
1946 smcr_link_hold(lnk: conn->lnk); /* link_put in smc_conn_free() */
1947 conn->freed = 0;
1948 conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
1949 conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
1950 conn->urg_state = SMC_URG_READ;
1951 init_waitqueue_head(&conn->cdc_pend_tx_wq);
1952 INIT_WORK(&smc->conn.abort_work, smc_conn_abort_work);
1953 if (ini->is_smcd) {
1954 conn->rx_off = sizeof(struct smcd_cdc_msg);
1955 smcd_cdc_rx_init(conn); /* init tasklet for this conn */
1956 } else {
1957 conn->rx_off = 0;
1958 }
1959#ifndef KERNEL_HAS_ATOMIC64
1960 spin_lock_init(&conn->acurs_lock);
1961#endif
1962
1963out:
1964 return rc;
1965}
1966
1967#define SMCD_DMBE_SIZES 6 /* 0 -> 16KB, 1 -> 32KB, .. 6 -> 1MB */
1968#define SMCR_RMBE_SIZES 5 /* 0 -> 16KB, 1 -> 32KB, .. 5 -> 512KB */
1969
1970/* convert the RMB size into the compressed notation (minimum 16K, see
1971 * SMCD/R_DMBE_SIZES.
1972 * In contrast to plain ilog2, this rounds towards the next power of 2,
1973 * so the socket application gets at least its desired sndbuf / rcvbuf size.
1974 */
1975static u8 smc_compress_bufsize(int size, bool is_smcd, bool is_rmb)
1976{
1977 const unsigned int max_scat = SG_MAX_SINGLE_ALLOC * PAGE_SIZE;
1978 u8 compressed;
1979
1980 if (size <= SMC_BUF_MIN_SIZE)
1981 return 0;
1982
1983 size = (size - 1) >> 14; /* convert to 16K multiple */
1984 compressed = min_t(u8, ilog2(size) + 1,
1985 is_smcd ? SMCD_DMBE_SIZES : SMCR_RMBE_SIZES);
1986
1987 if (!is_smcd && is_rmb)
1988 /* RMBs are backed by & limited to max size of scatterlists */
1989 compressed = min_t(u8, compressed, ilog2(max_scat >> 14));
1990
1991 return compressed;
1992}
1993
1994/* convert the RMB size from compressed notation into integer */
1995int smc_uncompress_bufsize(u8 compressed)
1996{
1997 u32 size;
1998
1999 size = 0x00000001 << (((int)compressed) + 14);
2000 return (int)size;
2001}
2002
2003/* try to reuse a sndbuf or rmb description slot for a certain
2004 * buffer size; if not available, return NULL
2005 */
2006static struct smc_buf_desc *smc_buf_get_slot(int compressed_bufsize,
2007 struct rw_semaphore *lock,
2008 struct list_head *buf_list)
2009{
2010 struct smc_buf_desc *buf_slot;
2011
2012 down_read(sem: lock);
2013 list_for_each_entry(buf_slot, buf_list, list) {
2014 if (cmpxchg(&buf_slot->used, 0, 1) == 0) {
2015 up_read(sem: lock);
2016 return buf_slot;
2017 }
2018 }
2019 up_read(sem: lock);
2020 return NULL;
2021}
2022
2023/* one of the conditions for announcing a receiver's current window size is
2024 * that it "results in a minimum increase in the window size of 10% of the
2025 * receive buffer space" [RFC7609]
2026 */
2027static inline int smc_rmb_wnd_update_limit(int rmbe_size)
2028{
2029 return max_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2);
2030}
2031
2032/* map an buf to a link */
2033static int smcr_buf_map_link(struct smc_buf_desc *buf_desc, bool is_rmb,
2034 struct smc_link *lnk)
2035{
2036 int rc, i, nents, offset, buf_size, size, access_flags;
2037 struct scatterlist *sg;
2038 void *buf;
2039
2040 if (buf_desc->is_map_ib[lnk->link_idx])
2041 return 0;
2042
2043 if (buf_desc->is_vm) {
2044 buf = buf_desc->cpu_addr;
2045 buf_size = buf_desc->len;
2046 offset = offset_in_page(buf_desc->cpu_addr);
2047 nents = PAGE_ALIGN(buf_size + offset) / PAGE_SIZE;
2048 } else {
2049 nents = 1;
2050 }
2051
2052 rc = sg_alloc_table(&buf_desc->sgt[lnk->link_idx], nents, GFP_KERNEL);
2053 if (rc)
2054 return rc;
2055
2056 if (buf_desc->is_vm) {
2057 /* virtually contiguous buffer */
2058 for_each_sg(buf_desc->sgt[lnk->link_idx].sgl, sg, nents, i) {
2059 size = min_t(int, PAGE_SIZE - offset, buf_size);
2060 sg_set_page(sg, page: vmalloc_to_page(addr: buf), len: size, offset);
2061 buf += size / sizeof(*buf);
2062 buf_size -= size;
2063 offset = 0;
2064 }
2065 } else {
2066 /* physically contiguous buffer */
2067 sg_set_buf(sg: buf_desc->sgt[lnk->link_idx].sgl,
2068 buf: buf_desc->cpu_addr, buflen: buf_desc->len);
2069 }
2070
2071 /* map sg table to DMA address */
2072 rc = smc_ib_buf_map_sg(lnk, buf_slot: buf_desc,
2073 data_direction: is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2074 /* SMC protocol depends on mapping to one DMA address only */
2075 if (rc != nents) {
2076 rc = -EAGAIN;
2077 goto free_table;
2078 }
2079
2080 buf_desc->is_dma_need_sync |=
2081 smc_ib_is_sg_need_sync(lnk, buf_slot: buf_desc) << lnk->link_idx;
2082
2083 if (is_rmb || buf_desc->is_vm) {
2084 /* create a new memory region for the RMB or vzalloced sndbuf */
2085 access_flags = is_rmb ?
2086 IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
2087 IB_ACCESS_LOCAL_WRITE;
2088
2089 rc = smc_ib_get_memory_region(pd: lnk->roce_pd, access_flags,
2090 buf_slot: buf_desc, link_idx: lnk->link_idx);
2091 if (rc)
2092 goto buf_unmap;
2093 smc_ib_sync_sg_for_device(lnk, buf_slot: buf_desc,
2094 data_direction: is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2095 }
2096 buf_desc->is_map_ib[lnk->link_idx] = true;
2097 return 0;
2098
2099buf_unmap:
2100 smc_ib_buf_unmap_sg(lnk, buf_slot: buf_desc,
2101 data_direction: is_rmb ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
2102free_table:
2103 sg_free_table(&buf_desc->sgt[lnk->link_idx]);
2104 return rc;
2105}
2106
2107/* register a new buf on IB device, rmb or vzalloced sndbuf
2108 * must be called under lgr->llc_conf_mutex lock
2109 */
2110int smcr_link_reg_buf(struct smc_link *link, struct smc_buf_desc *buf_desc)
2111{
2112 if (list_empty(head: &link->lgr->list))
2113 return -ENOLINK;
2114 if (!buf_desc->is_reg_mr[link->link_idx]) {
2115 /* register memory region for new buf */
2116 if (buf_desc->is_vm)
2117 buf_desc->mr[link->link_idx]->iova =
2118 (uintptr_t)buf_desc->cpu_addr;
2119 if (smc_wr_reg_send(link, mr: buf_desc->mr[link->link_idx])) {
2120 buf_desc->is_reg_err = true;
2121 return -EFAULT;
2122 }
2123 buf_desc->is_reg_mr[link->link_idx] = true;
2124 }
2125 return 0;
2126}
2127
2128static int _smcr_buf_map_lgr(struct smc_link *lnk, struct rw_semaphore *lock,
2129 struct list_head *lst, bool is_rmb)
2130{
2131 struct smc_buf_desc *buf_desc, *bf;
2132 int rc = 0;
2133
2134 down_write(sem: lock);
2135 list_for_each_entry_safe(buf_desc, bf, lst, list) {
2136 if (!buf_desc->used)
2137 continue;
2138 rc = smcr_buf_map_link(buf_desc, is_rmb, lnk);
2139 if (rc)
2140 goto out;
2141 }
2142out:
2143 up_write(sem: lock);
2144 return rc;
2145}
2146
2147/* map all used buffers of lgr for a new link */
2148int smcr_buf_map_lgr(struct smc_link *lnk)
2149{
2150 struct smc_link_group *lgr = lnk->lgr;
2151 int i, rc = 0;
2152
2153 for (i = 0; i < SMC_RMBE_SIZES; i++) {
2154 rc = _smcr_buf_map_lgr(lnk, lock: &lgr->rmbs_lock,
2155 lst: &lgr->rmbs[i], is_rmb: true);
2156 if (rc)
2157 return rc;
2158 rc = _smcr_buf_map_lgr(lnk, lock: &lgr->sndbufs_lock,
2159 lst: &lgr->sndbufs[i], is_rmb: false);
2160 if (rc)
2161 return rc;
2162 }
2163 return 0;
2164}
2165
2166/* register all used buffers of lgr for a new link,
2167 * must be called under lgr->llc_conf_mutex lock
2168 */
2169int smcr_buf_reg_lgr(struct smc_link *lnk)
2170{
2171 struct smc_link_group *lgr = lnk->lgr;
2172 struct smc_buf_desc *buf_desc, *bf;
2173 int i, rc = 0;
2174
2175 /* reg all RMBs for a new link */
2176 down_write(sem: &lgr->rmbs_lock);
2177 for (i = 0; i < SMC_RMBE_SIZES; i++) {
2178 list_for_each_entry_safe(buf_desc, bf, &lgr->rmbs[i], list) {
2179 if (!buf_desc->used)
2180 continue;
2181 rc = smcr_link_reg_buf(link: lnk, buf_desc);
2182 if (rc) {
2183 up_write(sem: &lgr->rmbs_lock);
2184 return rc;
2185 }
2186 }
2187 }
2188 up_write(sem: &lgr->rmbs_lock);
2189
2190 if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2191 return rc;
2192
2193 /* reg all vzalloced sndbufs for a new link */
2194 down_write(sem: &lgr->sndbufs_lock);
2195 for (i = 0; i < SMC_RMBE_SIZES; i++) {
2196 list_for_each_entry_safe(buf_desc, bf, &lgr->sndbufs[i], list) {
2197 if (!buf_desc->used || !buf_desc->is_vm)
2198 continue;
2199 rc = smcr_link_reg_buf(link: lnk, buf_desc);
2200 if (rc) {
2201 up_write(sem: &lgr->sndbufs_lock);
2202 return rc;
2203 }
2204 }
2205 }
2206 up_write(sem: &lgr->sndbufs_lock);
2207 return rc;
2208}
2209
2210static struct smc_buf_desc *smcr_new_buf_create(struct smc_link_group *lgr,
2211 bool is_rmb, int bufsize)
2212{
2213 struct smc_buf_desc *buf_desc;
2214
2215 /* try to alloc a new buffer */
2216 buf_desc = kzalloc(size: sizeof(*buf_desc), GFP_KERNEL);
2217 if (!buf_desc)
2218 return ERR_PTR(error: -ENOMEM);
2219
2220 switch (lgr->buf_type) {
2221 case SMCR_PHYS_CONT_BUFS:
2222 case SMCR_MIXED_BUFS:
2223 buf_desc->order = get_order(size: bufsize);
2224 buf_desc->pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN |
2225 __GFP_NOMEMALLOC | __GFP_COMP |
2226 __GFP_NORETRY | __GFP_ZERO,
2227 order: buf_desc->order);
2228 if (buf_desc->pages) {
2229 buf_desc->cpu_addr =
2230 (void *)page_address(buf_desc->pages);
2231 buf_desc->len = bufsize;
2232 buf_desc->is_vm = false;
2233 break;
2234 }
2235 if (lgr->buf_type == SMCR_PHYS_CONT_BUFS)
2236 goto out;
2237 fallthrough; // try virtually continguous buf
2238 case SMCR_VIRT_CONT_BUFS:
2239 buf_desc->order = get_order(size: bufsize);
2240 buf_desc->cpu_addr = vzalloc(PAGE_SIZE << buf_desc->order);
2241 if (!buf_desc->cpu_addr)
2242 goto out;
2243 buf_desc->pages = NULL;
2244 buf_desc->len = bufsize;
2245 buf_desc->is_vm = true;
2246 break;
2247 }
2248 return buf_desc;
2249
2250out:
2251 kfree(objp: buf_desc);
2252 return ERR_PTR(error: -EAGAIN);
2253}
2254
2255/* map buf_desc on all usable links,
2256 * unused buffers stay mapped as long as the link is up
2257 */
2258static int smcr_buf_map_usable_links(struct smc_link_group *lgr,
2259 struct smc_buf_desc *buf_desc, bool is_rmb)
2260{
2261 int i, rc = 0, cnt = 0;
2262
2263 /* protect against parallel link reconfiguration */
2264 down_read(sem: &lgr->llc_conf_mutex);
2265 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2266 struct smc_link *lnk = &lgr->lnk[i];
2267
2268 if (!smc_link_usable(lnk))
2269 continue;
2270 if (smcr_buf_map_link(buf_desc, is_rmb, lnk)) {
2271 rc = -ENOMEM;
2272 goto out;
2273 }
2274 cnt++;
2275 }
2276out:
2277 up_read(sem: &lgr->llc_conf_mutex);
2278 if (!rc && !cnt)
2279 rc = -EINVAL;
2280 return rc;
2281}
2282
2283static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
2284 bool is_dmb, int bufsize)
2285{
2286 struct smc_buf_desc *buf_desc;
2287 int rc;
2288
2289 /* try to alloc a new DMB */
2290 buf_desc = kzalloc(size: sizeof(*buf_desc), GFP_KERNEL);
2291 if (!buf_desc)
2292 return ERR_PTR(error: -ENOMEM);
2293 if (is_dmb) {
2294 rc = smc_ism_register_dmb(lgr, buf_size: bufsize, dmb_desc: buf_desc);
2295 if (rc) {
2296 kfree(objp: buf_desc);
2297 if (rc == -ENOMEM)
2298 return ERR_PTR(error: -EAGAIN);
2299 if (rc == -ENOSPC)
2300 return ERR_PTR(error: -ENOSPC);
2301 return ERR_PTR(error: -EIO);
2302 }
2303 buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
2304 /* CDC header stored in buf. So, pretend it was smaller */
2305 buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
2306 } else {
2307 buf_desc->cpu_addr = kzalloc(size: bufsize, GFP_KERNEL |
2308 __GFP_NOWARN | __GFP_NORETRY |
2309 __GFP_NOMEMALLOC);
2310 if (!buf_desc->cpu_addr) {
2311 kfree(objp: buf_desc);
2312 return ERR_PTR(error: -EAGAIN);
2313 }
2314 buf_desc->len = bufsize;
2315 }
2316 return buf_desc;
2317}
2318
2319static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
2320{
2321 struct smc_buf_desc *buf_desc = ERR_PTR(error: -ENOMEM);
2322 struct smc_connection *conn = &smc->conn;
2323 struct smc_link_group *lgr = conn->lgr;
2324 struct list_head *buf_list;
2325 int bufsize, bufsize_comp;
2326 struct rw_semaphore *lock; /* lock buffer list */
2327 bool is_dgraded = false;
2328
2329 if (is_rmb)
2330 /* use socket recv buffer size (w/o overhead) as start value */
2331 bufsize = smc->sk.sk_rcvbuf / 2;
2332 else
2333 /* use socket send buffer size (w/o overhead) as start value */
2334 bufsize = smc->sk.sk_sndbuf / 2;
2335
2336 for (bufsize_comp = smc_compress_bufsize(size: bufsize, is_smcd, is_rmb);
2337 bufsize_comp >= 0; bufsize_comp--) {
2338 if (is_rmb) {
2339 lock = &lgr->rmbs_lock;
2340 buf_list = &lgr->rmbs[bufsize_comp];
2341 } else {
2342 lock = &lgr->sndbufs_lock;
2343 buf_list = &lgr->sndbufs[bufsize_comp];
2344 }
2345 bufsize = smc_uncompress_bufsize(compressed: bufsize_comp);
2346
2347 /* check for reusable slot in the link group */
2348 buf_desc = smc_buf_get_slot(compressed_bufsize: bufsize_comp, lock, buf_list);
2349 if (buf_desc) {
2350 buf_desc->is_dma_need_sync = 0;
2351 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2352 SMC_STAT_BUF_REUSE(smc, is_smcd, is_rmb);
2353 break; /* found reusable slot */
2354 }
2355
2356 if (is_smcd)
2357 buf_desc = smcd_new_buf_create(lgr, is_dmb: is_rmb, bufsize);
2358 else
2359 buf_desc = smcr_new_buf_create(lgr, is_rmb, bufsize);
2360
2361 if (PTR_ERR(ptr: buf_desc) == -ENOMEM)
2362 break;
2363 if (IS_ERR(ptr: buf_desc)) {
2364 if (!is_dgraded) {
2365 is_dgraded = true;
2366 SMC_STAT_RMB_DOWNGRADED(smc, is_smcd, is_rmb);
2367 }
2368 continue;
2369 }
2370
2371 SMC_STAT_RMB_ALLOC(smc, is_smcd, is_rmb);
2372 SMC_STAT_RMB_SIZE(smc, is_smcd, is_rmb, bufsize);
2373 buf_desc->used = 1;
2374 down_write(sem: lock);
2375 list_add(new: &buf_desc->list, head: buf_list);
2376 up_write(sem: lock);
2377 break; /* found */
2378 }
2379
2380 if (IS_ERR(ptr: buf_desc))
2381 return PTR_ERR(ptr: buf_desc);
2382
2383 if (!is_smcd) {
2384 if (smcr_buf_map_usable_links(lgr, buf_desc, is_rmb)) {
2385 smcr_buf_unuse(buf_desc, is_rmb, lgr);
2386 return -ENOMEM;
2387 }
2388 }
2389
2390 if (is_rmb) {
2391 conn->rmb_desc = buf_desc;
2392 conn->rmbe_size_comp = bufsize_comp;
2393 smc->sk.sk_rcvbuf = bufsize * 2;
2394 atomic_set(v: &conn->bytes_to_rcv, i: 0);
2395 conn->rmbe_update_limit =
2396 smc_rmb_wnd_update_limit(rmbe_size: buf_desc->len);
2397 if (is_smcd)
2398 smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
2399 } else {
2400 conn->sndbuf_desc = buf_desc;
2401 smc->sk.sk_sndbuf = bufsize * 2;
2402 atomic_set(v: &conn->sndbuf_space, i: bufsize);
2403 }
2404 return 0;
2405}
2406
2407void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn)
2408{
2409 if (!conn->sndbuf_desc->is_dma_need_sync)
2410 return;
2411 if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd ||
2412 !smc_link_active(lnk: conn->lnk))
2413 return;
2414 smc_ib_sync_sg_for_device(lnk: conn->lnk, buf_slot: conn->sndbuf_desc, data_direction: DMA_TO_DEVICE);
2415}
2416
2417void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn)
2418{
2419 int i;
2420
2421 if (!conn->rmb_desc->is_dma_need_sync)
2422 return;
2423 if (!smc_conn_lgr_valid(conn) || conn->lgr->is_smcd)
2424 return;
2425 for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
2426 if (!smc_link_active(lnk: &conn->lgr->lnk[i]))
2427 continue;
2428 smc_ib_sync_sg_for_cpu(lnk: &conn->lgr->lnk[i], buf_slot: conn->rmb_desc,
2429 data_direction: DMA_FROM_DEVICE);
2430 }
2431}
2432
2433/* create the send and receive buffer for an SMC socket;
2434 * receive buffers are called RMBs;
2435 * (even though the SMC protocol allows more than one RMB-element per RMB,
2436 * the Linux implementation uses just one RMB-element per RMB, i.e. uses an
2437 * extra RMB for every connection in a link group
2438 */
2439int smc_buf_create(struct smc_sock *smc, bool is_smcd)
2440{
2441 int rc;
2442
2443 /* create send buffer */
2444 rc = __smc_buf_create(smc, is_smcd, is_rmb: false);
2445 if (rc)
2446 return rc;
2447 /* create rmb */
2448 rc = __smc_buf_create(smc, is_smcd, is_rmb: true);
2449 if (rc) {
2450 down_write(sem: &smc->conn.lgr->sndbufs_lock);
2451 list_del(entry: &smc->conn.sndbuf_desc->list);
2452 up_write(sem: &smc->conn.lgr->sndbufs_lock);
2453 smc_buf_free(lgr: smc->conn.lgr, is_rmb: false, buf_desc: smc->conn.sndbuf_desc);
2454 smc->conn.sndbuf_desc = NULL;
2455 }
2456 return rc;
2457}
2458
2459static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr)
2460{
2461 int i;
2462
2463 for_each_clear_bit(i, lgr->rtokens_used_mask, SMC_RMBS_PER_LGR_MAX) {
2464 if (!test_and_set_bit(nr: i, addr: lgr->rtokens_used_mask))
2465 return i;
2466 }
2467 return -ENOSPC;
2468}
2469
2470static int smc_rtoken_find_by_link(struct smc_link_group *lgr, int lnk_idx,
2471 u32 rkey)
2472{
2473 int i;
2474
2475 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2476 if (test_bit(i, lgr->rtokens_used_mask) &&
2477 lgr->rtokens[i][lnk_idx].rkey == rkey)
2478 return i;
2479 }
2480 return -ENOENT;
2481}
2482
2483/* set rtoken for a new link to an existing rmb */
2484void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
2485 __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey)
2486{
2487 int rtok_idx;
2488
2489 rtok_idx = smc_rtoken_find_by_link(lgr, lnk_idx: link_idx, ntohl(nw_rkey_known));
2490 if (rtok_idx == -ENOENT)
2491 return;
2492 lgr->rtokens[rtok_idx][link_idx_new].rkey = ntohl(nw_rkey);
2493 lgr->rtokens[rtok_idx][link_idx_new].dma_addr = be64_to_cpu(nw_vaddr);
2494}
2495
2496/* set rtoken for a new link whose link_id is given */
2497void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
2498 __be64 nw_vaddr, __be32 nw_rkey)
2499{
2500 u64 dma_addr = be64_to_cpu(nw_vaddr);
2501 u32 rkey = ntohl(nw_rkey);
2502 bool found = false;
2503 int link_idx;
2504
2505 for (link_idx = 0; link_idx < SMC_LINKS_PER_LGR_MAX; link_idx++) {
2506 if (lgr->lnk[link_idx].link_id == link_id) {
2507 found = true;
2508 break;
2509 }
2510 }
2511 if (!found)
2512 return;
2513 lgr->rtokens[rtok_idx][link_idx].rkey = rkey;
2514 lgr->rtokens[rtok_idx][link_idx].dma_addr = dma_addr;
2515}
2516
2517/* add a new rtoken from peer */
2518int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey)
2519{
2520 struct smc_link_group *lgr = smc_get_lgr(link: lnk);
2521 u64 dma_addr = be64_to_cpu(nw_vaddr);
2522 u32 rkey = ntohl(nw_rkey);
2523 int i;
2524
2525 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2526 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2527 lgr->rtokens[i][lnk->link_idx].dma_addr == dma_addr &&
2528 test_bit(i, lgr->rtokens_used_mask)) {
2529 /* already in list */
2530 return i;
2531 }
2532 }
2533 i = smc_rmb_reserve_rtoken_idx(lgr);
2534 if (i < 0)
2535 return i;
2536 lgr->rtokens[i][lnk->link_idx].rkey = rkey;
2537 lgr->rtokens[i][lnk->link_idx].dma_addr = dma_addr;
2538 return i;
2539}
2540
2541/* delete an rtoken from all links */
2542int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey)
2543{
2544 struct smc_link_group *lgr = smc_get_lgr(link: lnk);
2545 u32 rkey = ntohl(nw_rkey);
2546 int i, j;
2547
2548 for (i = 0; i < SMC_RMBS_PER_LGR_MAX; i++) {
2549 if (lgr->rtokens[i][lnk->link_idx].rkey == rkey &&
2550 test_bit(i, lgr->rtokens_used_mask)) {
2551 for (j = 0; j < SMC_LINKS_PER_LGR_MAX; j++) {
2552 lgr->rtokens[i][j].rkey = 0;
2553 lgr->rtokens[i][j].dma_addr = 0;
2554 }
2555 clear_bit(nr: i, addr: lgr->rtokens_used_mask);
2556 return 0;
2557 }
2558 }
2559 return -ENOENT;
2560}
2561
2562/* save rkey and dma_addr received from peer during clc handshake */
2563int smc_rmb_rtoken_handling(struct smc_connection *conn,
2564 struct smc_link *lnk,
2565 struct smc_clc_msg_accept_confirm *clc)
2566{
2567 conn->rtoken_idx = smc_rtoken_add(lnk, nw_vaddr: clc->r0.rmb_dma_addr,
2568 nw_rkey: clc->r0.rmb_rkey);
2569 if (conn->rtoken_idx < 0)
2570 return conn->rtoken_idx;
2571 return 0;
2572}
2573
2574static void smc_core_going_away(void)
2575{
2576 struct smc_ib_device *smcibdev;
2577 struct smcd_dev *smcd;
2578
2579 mutex_lock(&smc_ib_devices.mutex);
2580 list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
2581 int i;
2582
2583 for (i = 0; i < SMC_MAX_PORTS; i++)
2584 set_bit(nr: i, addr: smcibdev->ports_going_away);
2585 }
2586 mutex_unlock(lock: &smc_ib_devices.mutex);
2587
2588 mutex_lock(&smcd_dev_list.mutex);
2589 list_for_each_entry(smcd, &smcd_dev_list.list, list) {
2590 smcd->going_away = 1;
2591 }
2592 mutex_unlock(lock: &smcd_dev_list.mutex);
2593}
2594
2595/* Clean up all SMC link groups */
2596static void smc_lgrs_shutdown(void)
2597{
2598 struct smcd_dev *smcd;
2599
2600 smc_core_going_away();
2601
2602 smc_smcr_terminate_all(NULL);
2603
2604 mutex_lock(&smcd_dev_list.mutex);
2605 list_for_each_entry(smcd, &smcd_dev_list.list, list)
2606 smc_smcd_terminate_all(smcd);
2607 mutex_unlock(lock: &smcd_dev_list.mutex);
2608}
2609
2610static int smc_core_reboot_event(struct notifier_block *this,
2611 unsigned long event, void *ptr)
2612{
2613 smc_lgrs_shutdown();
2614 smc_ib_unregister_client();
2615 smc_ism_exit();
2616 return 0;
2617}
2618
2619static struct notifier_block smc_reboot_notifier = {
2620 .notifier_call = smc_core_reboot_event,
2621};
2622
2623int __init smc_core_init(void)
2624{
2625 return register_reboot_notifier(&smc_reboot_notifier);
2626}
2627
2628/* Called (from smc_exit) when module is removed */
2629void smc_core_exit(void)
2630{
2631 unregister_reboot_notifier(&smc_reboot_notifier);
2632 smc_lgrs_shutdown();
2633}
2634

source code of linux/net/smc/smc_core.c