1/* Copyright (c) 2013 Coraid, Inc. See COPYING for GPL terms. */
2/*
3 * aoecmd.c
4 * Filesystem request handling methods
5 */
6
7#include <linux/ata.h>
8#include <linux/slab.h>
9#include <linux/hdreg.h>
10#include <linux/blk-mq.h>
11#include <linux/skbuff.h>
12#include <linux/netdevice.h>
13#include <linux/moduleparam.h>
14#include <linux/workqueue.h>
15#include <linux/kthread.h>
16#include <net/net_namespace.h>
17#include <asm/unaligned.h>
18#include <linux/uio.h>
19#include "aoe.h"
20
21#define MAXIOC (8192) /* default meant to avoid most soft lockups */
22
23static void ktcomplete(struct frame *, struct sk_buff *);
24static int count_targets(struct aoedev *d, int *untainted);
25
26static struct buf *nextbuf(struct aoedev *);
27
28static int aoe_deadsecs = 60 * 3;
29module_param(aoe_deadsecs, int, 0644);
30MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev.");
31
32static int aoe_maxout = 64;
33module_param(aoe_maxout, int, 0644);
34MODULE_PARM_DESC(aoe_maxout,
35 "Only aoe_maxout outstanding packets for every MAC on eX.Y.");
36
37/* The number of online cpus during module initialization gives us a
38 * convenient heuristic cap on the parallelism used for ktio threads
39 * doing I/O completion. It is not important that the cap equal the
40 * actual number of running CPUs at any given time, but because of CPU
41 * hotplug, we take care to use ncpus instead of using
42 * num_online_cpus() after module initialization.
43 */
44static int ncpus;
45
46/* mutex lock used for synchronization while thread spawning */
47static DEFINE_MUTEX(ktio_spawn_lock);
48
49static wait_queue_head_t *ktiowq;
50static struct ktstate *kts;
51
52/* io completion queue */
53struct iocq_ktio {
54 struct list_head head;
55 spinlock_t lock;
56};
57static struct iocq_ktio *iocq;
58
59static struct page *empty_page;
60
61static struct sk_buff *
62new_skb(ulong len)
63{
64 struct sk_buff *skb;
65
66 skb = alloc_skb(size: len + MAX_HEADER, GFP_ATOMIC);
67 if (skb) {
68 skb_reserve(skb, MAX_HEADER);
69 skb_reset_mac_header(skb);
70 skb_reset_network_header(skb);
71 skb->protocol = __constant_htons(ETH_P_AOE);
72 skb_checksum_none_assert(skb);
73 }
74 return skb;
75}
76
77static struct frame *
78getframe_deferred(struct aoedev *d, u32 tag)
79{
80 struct list_head *head, *pos, *nx;
81 struct frame *f;
82
83 head = &d->rexmitq;
84 list_for_each_safe(pos, nx, head) {
85 f = list_entry(pos, struct frame, head);
86 if (f->tag == tag) {
87 list_del(entry: pos);
88 return f;
89 }
90 }
91 return NULL;
92}
93
94static struct frame *
95getframe(struct aoedev *d, u32 tag)
96{
97 struct frame *f;
98 struct list_head *head, *pos, *nx;
99 u32 n;
100
101 n = tag % NFACTIVE;
102 head = &d->factive[n];
103 list_for_each_safe(pos, nx, head) {
104 f = list_entry(pos, struct frame, head);
105 if (f->tag == tag) {
106 list_del(entry: pos);
107 return f;
108 }
109 }
110 return NULL;
111}
112
113/*
114 * Leave the top bit clear so we have tagspace for userland.
115 * The bottom 16 bits are the xmit tick for rexmit/rttavg processing.
116 * This driver reserves tag -1 to mean "unused frame."
117 */
118static int
119newtag(struct aoedev *d)
120{
121 register ulong n;
122
123 n = jiffies & 0xffff;
124 return n | (++d->lasttag & 0x7fff) << 16;
125}
126
127static u32
128aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)
129{
130 u32 host_tag = newtag(d);
131
132 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
133 memcpy(h->dst, t->addr, sizeof h->dst);
134 h->type = __constant_cpu_to_be16(ETH_P_AOE);
135 h->verfl = AOE_HVER;
136 h->major = cpu_to_be16(d->aoemajor);
137 h->minor = d->aoeminor;
138 h->cmd = AOECMD_ATA;
139 h->tag = cpu_to_be32(host_tag);
140
141 return host_tag;
142}
143
144static inline void
145put_lba(struct aoe_atahdr *ah, sector_t lba)
146{
147 ah->lba0 = lba;
148 ah->lba1 = lba >>= 8;
149 ah->lba2 = lba >>= 8;
150 ah->lba3 = lba >>= 8;
151 ah->lba4 = lba >>= 8;
152 ah->lba5 = lba >>= 8;
153}
154
155static struct aoeif *
156ifrotate(struct aoetgt *t)
157{
158 struct aoeif *ifp;
159
160 ifp = t->ifp;
161 ifp++;
162 if (ifp >= &t->ifs[NAOEIFS] || ifp->nd == NULL)
163 ifp = t->ifs;
164 if (ifp->nd == NULL)
165 return NULL;
166 return t->ifp = ifp;
167}
168
169static void
170skb_pool_put(struct aoedev *d, struct sk_buff *skb)
171{
172 __skb_queue_tail(list: &d->skbpool, newsk: skb);
173}
174
175static struct sk_buff *
176skb_pool_get(struct aoedev *d)
177{
178 struct sk_buff *skb = skb_peek(list_: &d->skbpool);
179
180 if (skb && atomic_read(v: &skb_shinfo(skb)->dataref) == 1) {
181 __skb_unlink(skb, list: &d->skbpool);
182 return skb;
183 }
184 if (skb_queue_len(list_: &d->skbpool) < NSKBPOOLMAX &&
185 (skb = new_skb(ETH_ZLEN)))
186 return skb;
187
188 return NULL;
189}
190
191void
192aoe_freetframe(struct frame *f)
193{
194 struct aoetgt *t;
195
196 t = f->t;
197 f->buf = NULL;
198 memset(&f->iter, 0, sizeof(f->iter));
199 f->r_skb = NULL;
200 f->flags = 0;
201 list_add(new: &f->head, head: &t->ffree);
202}
203
204static struct frame *
205newtframe(struct aoedev *d, struct aoetgt *t)
206{
207 struct frame *f;
208 struct sk_buff *skb;
209 struct list_head *pos;
210
211 if (list_empty(head: &t->ffree)) {
212 if (t->falloc >= NSKBPOOLMAX*2)
213 return NULL;
214 f = kcalloc(n: 1, size: sizeof(*f), GFP_ATOMIC);
215 if (f == NULL)
216 return NULL;
217 t->falloc++;
218 f->t = t;
219 } else {
220 pos = t->ffree.next;
221 list_del(entry: pos);
222 f = list_entry(pos, struct frame, head);
223 }
224
225 skb = f->skb;
226 if (skb == NULL) {
227 f->skb = skb = new_skb(ETH_ZLEN);
228 if (!skb) {
229bail: aoe_freetframe(f);
230 return NULL;
231 }
232 }
233
234 if (atomic_read(v: &skb_shinfo(skb)->dataref) != 1) {
235 skb = skb_pool_get(d);
236 if (skb == NULL)
237 goto bail;
238 skb_pool_put(d, skb: f->skb);
239 f->skb = skb;
240 }
241
242 skb->truesize -= skb->data_len;
243 skb_shinfo(skb)->nr_frags = skb->data_len = 0;
244 skb_trim(skb, len: 0);
245 return f;
246}
247
248static struct frame *
249newframe(struct aoedev *d)
250{
251 struct frame *f;
252 struct aoetgt *t, **tt;
253 int totout = 0;
254 int use_tainted;
255 int has_untainted;
256
257 if (!d->targets || !d->targets[0]) {
258 printk(KERN_ERR "aoe: NULL TARGETS!\n");
259 return NULL;
260 }
261 tt = d->tgt; /* last used target */
262 for (use_tainted = 0, has_untainted = 0;;) {
263 tt++;
264 if (tt >= &d->targets[d->ntargets] || !*tt)
265 tt = d->targets;
266 t = *tt;
267 if (!t->taint) {
268 has_untainted = 1;
269 totout += t->nout;
270 }
271 if (t->nout < t->maxout
272 && (use_tainted || !t->taint)
273 && t->ifp->nd) {
274 f = newtframe(d, t);
275 if (f) {
276 ifrotate(t);
277 d->tgt = tt;
278 return f;
279 }
280 }
281 if (tt == d->tgt) { /* we've looped and found nada */
282 if (!use_tainted && !has_untainted)
283 use_tainted = 1;
284 else
285 break;
286 }
287 }
288 if (totout == 0) {
289 d->kicked++;
290 d->flags |= DEVFL_KICKME;
291 }
292 return NULL;
293}
294
295static void
296skb_fillup(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter)
297{
298 int frag = 0;
299 struct bio_vec bv;
300
301 __bio_for_each_segment(bv, bio, iter, iter)
302 skb_fill_page_desc(skb, i: frag++, page: bv.bv_page,
303 off: bv.bv_offset, size: bv.bv_len);
304}
305
306static void
307fhash(struct frame *f)
308{
309 struct aoedev *d = f->t->d;
310 u32 n;
311
312 n = f->tag % NFACTIVE;
313 list_add_tail(new: &f->head, head: &d->factive[n]);
314}
315
316static void
317ata_rw_frameinit(struct frame *f)
318{
319 struct aoetgt *t;
320 struct aoe_hdr *h;
321 struct aoe_atahdr *ah;
322 struct sk_buff *skb;
323 char writebit, extbit;
324
325 skb = f->skb;
326 h = (struct aoe_hdr *) skb_mac_header(skb);
327 ah = (struct aoe_atahdr *) (h + 1);
328 skb_put(skb, len: sizeof(*h) + sizeof(*ah));
329 memset(h, 0, skb->len);
330
331 writebit = 0x10;
332 extbit = 0x4;
333
334 t = f->t;
335 f->tag = aoehdr_atainit(d: t->d, t, h);
336 fhash(f);
337 t->nout++;
338 f->waited = 0;
339 f->waited_total = 0;
340
341 /* set up ata header */
342 ah->scnt = f->iter.bi_size >> 9;
343 put_lba(ah, lba: f->iter.bi_sector);
344 if (t->d->flags & DEVFL_EXT) {
345 ah->aflags |= AOEAFL_EXT;
346 } else {
347 extbit = 0;
348 ah->lba3 &= 0x0f;
349 ah->lba3 |= 0xe0; /* LBA bit + obsolete 0xa0 */
350 }
351 if (f->buf && bio_data_dir(f->buf->bio) == WRITE) {
352 skb_fillup(skb, bio: f->buf->bio, iter: f->iter);
353 ah->aflags |= AOEAFL_WRITE;
354 skb->len += f->iter.bi_size;
355 skb->data_len = f->iter.bi_size;
356 skb->truesize += f->iter.bi_size;
357 t->wpkts++;
358 } else {
359 t->rpkts++;
360 writebit = 0;
361 }
362
363 ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit;
364 skb->dev = t->ifp->nd;
365}
366
367static int
368aoecmd_ata_rw(struct aoedev *d)
369{
370 struct frame *f;
371 struct buf *buf;
372 struct sk_buff *skb;
373 struct sk_buff_head queue;
374
375 buf = nextbuf(d);
376 if (buf == NULL)
377 return 0;
378 f = newframe(d);
379 if (f == NULL)
380 return 0;
381
382 /* initialize the headers & frame */
383 f->buf = buf;
384 f->iter = buf->iter;
385 f->iter.bi_size = min_t(unsigned long,
386 d->maxbcnt ?: DEFAULTBCNT,
387 f->iter.bi_size);
388 bio_advance_iter(bio: buf->bio, iter: &buf->iter, bytes: f->iter.bi_size);
389
390 if (!buf->iter.bi_size)
391 d->ip.buf = NULL;
392
393 /* mark all tracking fields and load out */
394 buf->nframesout += 1;
395
396 ata_rw_frameinit(f);
397
398 skb = skb_clone(skb: f->skb, GFP_ATOMIC);
399 if (skb) {
400 f->sent = ktime_get();
401 __skb_queue_head_init(list: &queue);
402 __skb_queue_tail(list: &queue, newsk: skb);
403 aoenet_xmit(&queue);
404 }
405 return 1;
406}
407
408/* some callers cannot sleep, and they can call this function,
409 * transmitting the packets later, when interrupts are on
410 */
411static void
412aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue)
413{
414 struct aoe_hdr *h;
415 struct aoe_cfghdr *ch;
416 struct sk_buff *skb;
417 struct net_device *ifp;
418
419 rcu_read_lock();
420 for_each_netdev_rcu(&init_net, ifp) {
421 dev_hold(dev: ifp);
422 if (!is_aoe_netif(ifp)) {
423 dev_put(dev: ifp);
424 continue;
425 }
426
427 skb = new_skb(len: sizeof *h + sizeof *ch);
428 if (skb == NULL) {
429 printk(KERN_INFO "aoe: skb alloc failure\n");
430 dev_put(dev: ifp);
431 continue;
432 }
433 skb_put(skb, len: sizeof *h + sizeof *ch);
434 skb->dev = ifp;
435 __skb_queue_tail(list: queue, newsk: skb);
436 h = (struct aoe_hdr *) skb_mac_header(skb);
437 memset(h, 0, sizeof *h + sizeof *ch);
438
439 memset(h->dst, 0xff, sizeof h->dst);
440 memcpy(h->src, ifp->dev_addr, sizeof h->src);
441 h->type = __constant_cpu_to_be16(ETH_P_AOE);
442 h->verfl = AOE_HVER;
443 h->major = cpu_to_be16(aoemajor);
444 h->minor = aoeminor;
445 h->cmd = AOECMD_CFG;
446 }
447 rcu_read_unlock();
448}
449
450static void
451resend(struct aoedev *d, struct frame *f)
452{
453 struct sk_buff *skb;
454 struct sk_buff_head queue;
455 struct aoe_hdr *h;
456 struct aoetgt *t;
457 char buf[128];
458 u32 n;
459
460 t = f->t;
461 n = newtag(d);
462 skb = f->skb;
463 if (ifrotate(t) == NULL) {
464 /* probably can't happen, but set it up to fail anyway */
465 pr_info("aoe: resend: no interfaces to rotate to.\n");
466 ktcomplete(f, NULL);
467 return;
468 }
469 h = (struct aoe_hdr *) skb_mac_header(skb);
470
471 if (!(f->flags & FFL_PROBE)) {
472 snprintf(buf, size: sizeof(buf),
473 fmt: "%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n",
474 "retransmit", d->aoemajor, d->aoeminor,
475 f->tag, jiffies, n,
476 h->src, h->dst, t->nout);
477 aoechr_error(buf);
478 }
479
480 f->tag = n;
481 fhash(f);
482 h->tag = cpu_to_be32(n);
483 memcpy(h->dst, t->addr, sizeof h->dst);
484 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
485
486 skb->dev = t->ifp->nd;
487 skb = skb_clone(skb, GFP_ATOMIC);
488 if (skb == NULL)
489 return;
490 f->sent = ktime_get();
491 __skb_queue_head_init(list: &queue);
492 __skb_queue_tail(list: &queue, newsk: skb);
493 aoenet_xmit(&queue);
494}
495
496static int
497tsince_hr(struct frame *f)
498{
499 u64 delta = ktime_to_ns(ktime_sub(ktime_get(), f->sent));
500
501 /* delta is normally under 4.2 seconds, avoid 64-bit division */
502 if (likely(delta <= UINT_MAX))
503 return (u32)delta / NSEC_PER_USEC;
504
505 /* avoid overflow after 71 minutes */
506 if (delta > ((u64)INT_MAX * NSEC_PER_USEC))
507 return INT_MAX;
508
509 return div_u64(dividend: delta, NSEC_PER_USEC);
510}
511
512static int
513tsince(u32 tag)
514{
515 int n;
516
517 n = jiffies & 0xffff;
518 n -= tag & 0xffff;
519 if (n < 0)
520 n += 1<<16;
521 return jiffies_to_usecs(j: n + 1);
522}
523
524static struct aoeif *
525getif(struct aoetgt *t, struct net_device *nd)
526{
527 struct aoeif *p, *e;
528
529 p = t->ifs;
530 e = p + NAOEIFS;
531 for (; p < e; p++)
532 if (p->nd == nd)
533 return p;
534 return NULL;
535}
536
537static void
538ejectif(struct aoetgt *t, struct aoeif *ifp)
539{
540 struct aoeif *e;
541 struct net_device *nd;
542 ulong n;
543
544 nd = ifp->nd;
545 e = t->ifs + NAOEIFS - 1;
546 n = (e - ifp) * sizeof *ifp;
547 memmove(ifp, ifp+1, n);
548 e->nd = NULL;
549 dev_put(dev: nd);
550}
551
552static struct frame *
553reassign_frame(struct frame *f)
554{
555 struct frame *nf;
556 struct sk_buff *skb;
557
558 nf = newframe(d: f->t->d);
559 if (!nf)
560 return NULL;
561 if (nf->t == f->t) {
562 aoe_freetframe(f: nf);
563 return NULL;
564 }
565
566 skb = nf->skb;
567 nf->skb = f->skb;
568 nf->buf = f->buf;
569 nf->iter = f->iter;
570 nf->waited = 0;
571 nf->waited_total = f->waited_total;
572 nf->sent = f->sent;
573 f->skb = skb;
574
575 return nf;
576}
577
578static void
579probe(struct aoetgt *t)
580{
581 struct aoedev *d;
582 struct frame *f;
583 struct sk_buff *skb;
584 struct sk_buff_head queue;
585 size_t n, m;
586 int frag;
587
588 d = t->d;
589 f = newtframe(d, t);
590 if (!f) {
591 pr_err("%s %pm for e%ld.%d: %s\n",
592 "aoe: cannot probe remote address",
593 t->addr,
594 (long) d->aoemajor, d->aoeminor,
595 "no frame available");
596 return;
597 }
598 f->flags |= FFL_PROBE;
599 ifrotate(t);
600 f->iter.bi_size = t->d->maxbcnt ? t->d->maxbcnt : DEFAULTBCNT;
601 ata_rw_frameinit(f);
602 skb = f->skb;
603 for (frag = 0, n = f->iter.bi_size; n > 0; ++frag, n -= m) {
604 if (n < PAGE_SIZE)
605 m = n;
606 else
607 m = PAGE_SIZE;
608 skb_fill_page_desc(skb, i: frag, page: empty_page, off: 0, size: m);
609 }
610 skb->len += f->iter.bi_size;
611 skb->data_len = f->iter.bi_size;
612 skb->truesize += f->iter.bi_size;
613
614 skb = skb_clone(skb: f->skb, GFP_ATOMIC);
615 if (skb) {
616 f->sent = ktime_get();
617 __skb_queue_head_init(list: &queue);
618 __skb_queue_tail(list: &queue, newsk: skb);
619 aoenet_xmit(&queue);
620 }
621}
622
623static long
624rto(struct aoedev *d)
625{
626 long t;
627
628 t = 2 * d->rttavg >> RTTSCALE;
629 t += 8 * d->rttdev >> RTTDSCALE;
630 if (t == 0)
631 t = 1;
632
633 return t;
634}
635
636static void
637rexmit_deferred(struct aoedev *d)
638{
639 struct aoetgt *t;
640 struct frame *f;
641 struct frame *nf;
642 struct list_head *pos, *nx, *head;
643 int since;
644 int untainted;
645
646 count_targets(d, untainted: &untainted);
647
648 head = &d->rexmitq;
649 list_for_each_safe(pos, nx, head) {
650 f = list_entry(pos, struct frame, head);
651 t = f->t;
652 if (t->taint) {
653 if (!(f->flags & FFL_PROBE)) {
654 nf = reassign_frame(f);
655 if (nf) {
656 if (t->nout_probes == 0
657 && untainted > 0) {
658 probe(t);
659 t->nout_probes++;
660 }
661 list_replace(old: &f->head, new: &nf->head);
662 pos = &nf->head;
663 aoe_freetframe(f);
664 f = nf;
665 t = f->t;
666 }
667 } else if (untainted < 1) {
668 /* don't probe w/o other untainted aoetgts */
669 goto stop_probe;
670 } else if (tsince_hr(f) < t->taint * rto(d)) {
671 /* reprobe slowly when taint is high */
672 continue;
673 }
674 } else if (f->flags & FFL_PROBE) {
675stop_probe: /* don't probe untainted aoetgts */
676 list_del(entry: pos);
677 aoe_freetframe(f);
678 /* leaving d->kicked, because this is routine */
679 f->t->d->flags |= DEVFL_KICKME;
680 continue;
681 }
682 if (t->nout >= t->maxout)
683 continue;
684 list_del(entry: pos);
685 t->nout++;
686 if (f->flags & FFL_PROBE)
687 t->nout_probes++;
688 since = tsince_hr(f);
689 f->waited += since;
690 f->waited_total += since;
691 resend(d, f);
692 }
693}
694
695/* An aoetgt accumulates demerits quickly, and successful
696 * probing redeems the aoetgt slowly.
697 */
698static void
699scorn(struct aoetgt *t)
700{
701 int n;
702
703 n = t->taint++;
704 t->taint += t->taint * 2;
705 if (n > t->taint)
706 t->taint = n;
707 if (t->taint > MAX_TAINT)
708 t->taint = MAX_TAINT;
709}
710
711static int
712count_targets(struct aoedev *d, int *untainted)
713{
714 int i, good;
715
716 for (i = good = 0; i < d->ntargets && d->targets[i]; ++i)
717 if (d->targets[i]->taint == 0)
718 good++;
719
720 if (untainted)
721 *untainted = good;
722 return i;
723}
724
725static void
726rexmit_timer(struct timer_list *timer)
727{
728 struct aoedev *d;
729 struct aoetgt *t;
730 struct aoeif *ifp;
731 struct frame *f;
732 struct list_head *head, *pos, *nx;
733 LIST_HEAD(flist);
734 register long timeout;
735 ulong flags, n;
736 int i;
737 int utgts; /* number of aoetgt descriptors (not slots) */
738 int since;
739
740 d = from_timer(d, timer, timer);
741
742 spin_lock_irqsave(&d->lock, flags);
743
744 /* timeout based on observed timings and variations */
745 timeout = rto(d);
746
747 utgts = count_targets(d, NULL);
748
749 if (d->flags & DEVFL_TKILL) {
750 spin_unlock_irqrestore(lock: &d->lock, flags);
751 return;
752 }
753
754 /* collect all frames to rexmit into flist */
755 for (i = 0; i < NFACTIVE; i++) {
756 head = &d->factive[i];
757 list_for_each_safe(pos, nx, head) {
758 f = list_entry(pos, struct frame, head);
759 if (tsince_hr(f) < timeout)
760 break; /* end of expired frames */
761 /* move to flist for later processing */
762 list_move_tail(list: pos, head: &flist);
763 }
764 }
765
766 /* process expired frames */
767 while (!list_empty(head: &flist)) {
768 pos = flist.next;
769 f = list_entry(pos, struct frame, head);
770 since = tsince_hr(f);
771 n = f->waited_total + since;
772 n /= USEC_PER_SEC;
773 if (aoe_deadsecs
774 && n > aoe_deadsecs
775 && !(f->flags & FFL_PROBE)) {
776 /* Waited too long. Device failure.
777 * Hang all frames on first hash bucket for downdev
778 * to clean up.
779 */
780 list_splice(list: &flist, head: &d->factive[0]);
781 aoedev_downdev(d);
782 goto out;
783 }
784
785 t = f->t;
786 n = f->waited + since;
787 n /= USEC_PER_SEC;
788 if (aoe_deadsecs && utgts > 0
789 && (n > aoe_deadsecs / utgts || n > HARD_SCORN_SECS))
790 scorn(t); /* avoid this target */
791
792 if (t->maxout != 1) {
793 t->ssthresh = t->maxout / 2;
794 t->maxout = 1;
795 }
796
797 if (f->flags & FFL_PROBE) {
798 t->nout_probes--;
799 } else {
800 ifp = getif(t, nd: f->skb->dev);
801 if (ifp && ++ifp->lost > (t->nframes << 1)
802 && (ifp != t->ifs || t->ifs[1].nd)) {
803 ejectif(t, ifp);
804 ifp = NULL;
805 }
806 }
807 list_move_tail(list: pos, head: &d->rexmitq);
808 t->nout--;
809 }
810 rexmit_deferred(d);
811
812out:
813 if ((d->flags & DEVFL_KICKME) && d->blkq) {
814 d->flags &= ~DEVFL_KICKME;
815 blk_mq_run_hw_queues(q: d->blkq, async: true);
816 }
817
818 d->timer.expires = jiffies + TIMERTICK;
819 add_timer(timer: &d->timer);
820
821 spin_unlock_irqrestore(lock: &d->lock, flags);
822}
823
824static void
825bufinit(struct buf *buf, struct request *rq, struct bio *bio)
826{
827 memset(buf, 0, sizeof(*buf));
828 buf->rq = rq;
829 buf->bio = bio;
830 buf->iter = bio->bi_iter;
831}
832
833static struct buf *
834nextbuf(struct aoedev *d)
835{
836 struct request *rq;
837 struct request_queue *q;
838 struct aoe_req *req;
839 struct buf *buf;
840 struct bio *bio;
841
842 q = d->blkq;
843 if (q == NULL)
844 return NULL; /* initializing */
845 if (d->ip.buf)
846 return d->ip.buf;
847 rq = d->ip.rq;
848 if (rq == NULL) {
849 rq = list_first_entry_or_null(&d->rq_list, struct request,
850 queuelist);
851 if (rq == NULL)
852 return NULL;
853 list_del_init(entry: &rq->queuelist);
854 blk_mq_start_request(rq);
855 d->ip.rq = rq;
856 d->ip.nxbio = rq->bio;
857
858 req = blk_mq_rq_to_pdu(rq);
859 req->nr_bios = 0;
860 __rq_for_each_bio(bio, rq)
861 req->nr_bios++;
862 }
863 buf = mempool_alloc(pool: d->bufpool, GFP_ATOMIC);
864 if (buf == NULL) {
865 pr_err("aoe: nextbuf: unable to mempool_alloc!\n");
866 return NULL;
867 }
868 bio = d->ip.nxbio;
869 bufinit(buf, rq, bio);
870 bio = bio->bi_next;
871 d->ip.nxbio = bio;
872 if (bio == NULL)
873 d->ip.rq = NULL;
874 return d->ip.buf = buf;
875}
876
877/* enters with d->lock held */
878void
879aoecmd_work(struct aoedev *d)
880{
881 rexmit_deferred(d);
882 while (aoecmd_ata_rw(d))
883 ;
884}
885
886/* this function performs work that has been deferred until sleeping is OK
887 */
888void
889aoecmd_sleepwork(struct work_struct *work)
890{
891 struct aoedev *d = container_of(work, struct aoedev, work);
892
893 if (d->flags & DEVFL_GDALLOC)
894 aoeblk_gdalloc(d);
895
896 if (d->flags & DEVFL_NEWSIZE) {
897 set_capacity_and_notify(disk: d->gd, size: d->ssize);
898
899 spin_lock_irq(lock: &d->lock);
900 d->flags |= DEVFL_UP;
901 d->flags &= ~DEVFL_NEWSIZE;
902 spin_unlock_irq(lock: &d->lock);
903 }
904}
905
906static void
907ata_ident_fixstring(u16 *id, int ns)
908{
909 u16 s;
910
911 while (ns-- > 0) {
912 s = *id;
913 *id++ = s >> 8 | s << 8;
914 }
915}
916
917static void
918ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
919{
920 u64 ssize;
921 u16 n;
922
923 /* word 83: command set supported */
924 n = get_unaligned_le16(p: &id[83 << 1]);
925
926 /* word 86: command set/feature enabled */
927 n |= get_unaligned_le16(p: &id[86 << 1]);
928
929 if (n & (1<<10)) { /* bit 10: LBA 48 */
930 d->flags |= DEVFL_EXT;
931
932 /* word 100: number lba48 sectors */
933 ssize = get_unaligned_le64(p: &id[100 << 1]);
934
935 /* set as in ide-disk.c:init_idedisk_capacity */
936 d->geo.cylinders = ssize;
937 d->geo.cylinders /= (255 * 63);
938 d->geo.heads = 255;
939 d->geo.sectors = 63;
940 } else {
941 d->flags &= ~DEVFL_EXT;
942
943 /* number lba28 sectors */
944 ssize = get_unaligned_le32(p: &id[60 << 1]);
945
946 /* NOTE: obsolete in ATA 6 */
947 d->geo.cylinders = get_unaligned_le16(p: &id[54 << 1]);
948 d->geo.heads = get_unaligned_le16(p: &id[55 << 1]);
949 d->geo.sectors = get_unaligned_le16(p: &id[56 << 1]);
950 }
951
952 ata_ident_fixstring(id: (u16 *) &id[10<<1], ns: 10); /* serial */
953 ata_ident_fixstring(id: (u16 *) &id[23<<1], ns: 4); /* firmware */
954 ata_ident_fixstring(id: (u16 *) &id[27<<1], ns: 20); /* model */
955 memcpy(d->ident, id, sizeof(d->ident));
956
957 if (d->ssize != ssize)
958 printk(KERN_INFO
959 "aoe: %pm e%ld.%d v%04x has %llu sectors\n",
960 t->addr,
961 d->aoemajor, d->aoeminor,
962 d->fw_ver, (long long)ssize);
963 d->ssize = ssize;
964 d->geo.start = 0;
965 if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
966 return;
967 if (d->gd != NULL)
968 d->flags |= DEVFL_NEWSIZE;
969 else
970 d->flags |= DEVFL_GDALLOC;
971 queue_work(wq: aoe_wq, work: &d->work);
972}
973
974static void
975calc_rttavg(struct aoedev *d, struct aoetgt *t, int rtt)
976{
977 register long n;
978
979 n = rtt;
980
981 /* cf. Congestion Avoidance and Control, Jacobson & Karels, 1988 */
982 n -= d->rttavg >> RTTSCALE;
983 d->rttavg += n;
984 if (n < 0)
985 n = -n;
986 n -= d->rttdev >> RTTDSCALE;
987 d->rttdev += n;
988
989 if (!t || t->maxout >= t->nframes)
990 return;
991 if (t->maxout < t->ssthresh)
992 t->maxout += 1;
993 else if (t->nout == t->maxout && t->next_cwnd-- == 0) {
994 t->maxout += 1;
995 t->next_cwnd = t->maxout;
996 }
997}
998
999static struct aoetgt *
1000gettgt(struct aoedev *d, char *addr)
1001{
1002 struct aoetgt **t, **e;
1003
1004 t = d->targets;
1005 e = t + d->ntargets;
1006 for (; t < e && *t; t++)
1007 if (memcmp(p: (*t)->addr, q: addr, size: sizeof((*t)->addr)) == 0)
1008 return *t;
1009 return NULL;
1010}
1011
1012static void
1013bvcpy(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter, long cnt)
1014{
1015 int soff = 0;
1016 struct bio_vec bv;
1017
1018 iter.bi_size = cnt;
1019
1020 __bio_for_each_segment(bv, bio, iter, iter) {
1021 char *p = bvec_kmap_local(bvec: &bv);
1022 skb_copy_bits(skb, offset: soff, to: p, len: bv.bv_len);
1023 kunmap_local(p);
1024 soff += bv.bv_len;
1025 }
1026}
1027
1028void
1029aoe_end_request(struct aoedev *d, struct request *rq, int fastfail)
1030{
1031 struct bio *bio;
1032 int bok;
1033 struct request_queue *q;
1034 blk_status_t err = BLK_STS_OK;
1035
1036 q = d->blkq;
1037 if (rq == d->ip.rq)
1038 d->ip.rq = NULL;
1039 do {
1040 bio = rq->bio;
1041 bok = !fastfail && !bio->bi_status;
1042 if (!bok)
1043 err = BLK_STS_IOERR;
1044 } while (blk_update_request(rq, error: bok ? BLK_STS_OK : BLK_STS_IOERR, nr_bytes: bio->bi_iter.bi_size));
1045
1046 __blk_mq_end_request(rq, error: err);
1047
1048 /* cf. https://lore.kernel.org/lkml/20061031071040.GS14055@kernel.dk/ */
1049 if (!fastfail)
1050 blk_mq_run_hw_queues(q, async: true);
1051}
1052
1053static void
1054aoe_end_buf(struct aoedev *d, struct buf *buf)
1055{
1056 struct request *rq = buf->rq;
1057 struct aoe_req *req = blk_mq_rq_to_pdu(rq);
1058
1059 if (buf == d->ip.buf)
1060 d->ip.buf = NULL;
1061 mempool_free(element: buf, pool: d->bufpool);
1062 if (--req->nr_bios == 0)
1063 aoe_end_request(d, rq, fastfail: 0);
1064}
1065
1066static void
1067ktiocomplete(struct frame *f)
1068{
1069 struct aoe_hdr *hin, *hout;
1070 struct aoe_atahdr *ahin, *ahout;
1071 struct buf *buf;
1072 struct sk_buff *skb;
1073 struct aoetgt *t;
1074 struct aoeif *ifp;
1075 struct aoedev *d;
1076 long n;
1077 int untainted;
1078
1079 if (f == NULL)
1080 return;
1081
1082 t = f->t;
1083 d = t->d;
1084 skb = f->r_skb;
1085 buf = f->buf;
1086 if (f->flags & FFL_PROBE)
1087 goto out;
1088 if (!skb) /* just fail the buf. */
1089 goto noskb;
1090
1091 hout = (struct aoe_hdr *) skb_mac_header(skb: f->skb);
1092 ahout = (struct aoe_atahdr *) (hout+1);
1093
1094 hin = (struct aoe_hdr *) skb->data;
1095 skb_pull(skb, len: sizeof(*hin));
1096 ahin = (struct aoe_atahdr *) skb->data;
1097 skb_pull(skb, len: sizeof(*ahin));
1098 if (ahin->cmdstat & 0xa9) { /* these bits cleared on success */
1099 pr_err("aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n",
1100 ahout->cmdstat, ahin->cmdstat,
1101 d->aoemajor, d->aoeminor);
1102noskb: if (buf)
1103 buf->bio->bi_status = BLK_STS_IOERR;
1104 goto out;
1105 }
1106
1107 n = ahout->scnt << 9;
1108 switch (ahout->cmdstat) {
1109 case ATA_CMD_PIO_READ:
1110 case ATA_CMD_PIO_READ_EXT:
1111 if (skb->len < n) {
1112 pr_err("%s e%ld.%d. skb->len=%d need=%ld\n",
1113 "aoe: runt data size in read from",
1114 (long) d->aoemajor, d->aoeminor,
1115 skb->len, n);
1116 buf->bio->bi_status = BLK_STS_IOERR;
1117 break;
1118 }
1119 if (n > f->iter.bi_size) {
1120 pr_err_ratelimited("%s e%ld.%d. bytes=%ld need=%u\n",
1121 "aoe: too-large data size in read from",
1122 (long) d->aoemajor, d->aoeminor,
1123 n, f->iter.bi_size);
1124 buf->bio->bi_status = BLK_STS_IOERR;
1125 break;
1126 }
1127 bvcpy(skb, bio: f->buf->bio, iter: f->iter, cnt: n);
1128 fallthrough;
1129 case ATA_CMD_PIO_WRITE:
1130 case ATA_CMD_PIO_WRITE_EXT:
1131 spin_lock_irq(lock: &d->lock);
1132 ifp = getif(t, nd: skb->dev);
1133 if (ifp)
1134 ifp->lost = 0;
1135 spin_unlock_irq(lock: &d->lock);
1136 break;
1137 case ATA_CMD_ID_ATA:
1138 if (skb->len < 512) {
1139 pr_info("%s e%ld.%d. skb->len=%d need=512\n",
1140 "aoe: runt data size in ataid from",
1141 (long) d->aoemajor, d->aoeminor,
1142 skb->len);
1143 break;
1144 }
1145 if (skb_linearize(skb))
1146 break;
1147 spin_lock_irq(lock: &d->lock);
1148 ataid_complete(d, t, id: skb->data);
1149 spin_unlock_irq(lock: &d->lock);
1150 break;
1151 default:
1152 pr_info("aoe: unrecognized ata command %2.2Xh for %d.%d\n",
1153 ahout->cmdstat,
1154 be16_to_cpu(get_unaligned(&hin->major)),
1155 hin->minor);
1156 }
1157out:
1158 spin_lock_irq(lock: &d->lock);
1159 if (t->taint > 0
1160 && --t->taint > 0
1161 && t->nout_probes == 0) {
1162 count_targets(d, untainted: &untainted);
1163 if (untainted > 0) {
1164 probe(t);
1165 t->nout_probes++;
1166 }
1167 }
1168
1169 aoe_freetframe(f);
1170
1171 if (buf && --buf->nframesout == 0 && buf->iter.bi_size == 0)
1172 aoe_end_buf(d, buf);
1173
1174 spin_unlock_irq(lock: &d->lock);
1175 aoedev_put(d);
1176 dev_kfree_skb(skb);
1177}
1178
1179/* Enters with iocq.lock held.
1180 * Returns true iff responses needing processing remain.
1181 */
1182static int
1183ktio(int id)
1184{
1185 struct frame *f;
1186 struct list_head *pos;
1187 int i;
1188 int actual_id;
1189
1190 for (i = 0; ; ++i) {
1191 if (i == MAXIOC)
1192 return 1;
1193 if (list_empty(head: &iocq[id].head))
1194 return 0;
1195 pos = iocq[id].head.next;
1196 list_del(entry: pos);
1197 f = list_entry(pos, struct frame, head);
1198 spin_unlock_irq(lock: &iocq[id].lock);
1199 ktiocomplete(f);
1200
1201 /* Figure out if extra threads are required. */
1202 actual_id = f->t->d->aoeminor % ncpus;
1203
1204 if (!kts[actual_id].active) {
1205 BUG_ON(id != 0);
1206 mutex_lock(&ktio_spawn_lock);
1207 if (!kts[actual_id].active
1208 && aoe_ktstart(k: &kts[actual_id]) == 0)
1209 kts[actual_id].active = 1;
1210 mutex_unlock(lock: &ktio_spawn_lock);
1211 }
1212 spin_lock_irq(lock: &iocq[id].lock);
1213 }
1214}
1215
1216static int
1217kthread(void *vp)
1218{
1219 struct ktstate *k;
1220 DECLARE_WAITQUEUE(wait, current);
1221 int more;
1222
1223 k = vp;
1224 current->flags |= PF_NOFREEZE;
1225 set_user_nice(current, nice: -10);
1226 complete(&k->rendez); /* tell spawner we're running */
1227 do {
1228 spin_lock_irq(lock: k->lock);
1229 more = k->fn(k->id);
1230 if (!more) {
1231 add_wait_queue(wq_head: k->waitq, wq_entry: &wait);
1232 __set_current_state(TASK_INTERRUPTIBLE);
1233 }
1234 spin_unlock_irq(lock: k->lock);
1235 if (!more) {
1236 schedule();
1237 remove_wait_queue(wq_head: k->waitq, wq_entry: &wait);
1238 } else
1239 cond_resched();
1240 } while (!kthread_should_stop());
1241 complete(&k->rendez); /* tell spawner we're stopping */
1242 return 0;
1243}
1244
1245void
1246aoe_ktstop(struct ktstate *k)
1247{
1248 kthread_stop(k: k->task);
1249 wait_for_completion(&k->rendez);
1250}
1251
1252int
1253aoe_ktstart(struct ktstate *k)
1254{
1255 struct task_struct *task;
1256
1257 init_completion(x: &k->rendez);
1258 task = kthread_run(kthread, k, "%s", k->name);
1259 if (task == NULL || IS_ERR(ptr: task))
1260 return -ENOMEM;
1261 k->task = task;
1262 wait_for_completion(&k->rendez); /* allow kthread to start */
1263 init_completion(x: &k->rendez); /* for waiting for exit later */
1264 return 0;
1265}
1266
1267/* pass it off to kthreads for processing */
1268static void
1269ktcomplete(struct frame *f, struct sk_buff *skb)
1270{
1271 int id;
1272 ulong flags;
1273
1274 f->r_skb = skb;
1275 id = f->t->d->aoeminor % ncpus;
1276 spin_lock_irqsave(&iocq[id].lock, flags);
1277 if (!kts[id].active) {
1278 spin_unlock_irqrestore(lock: &iocq[id].lock, flags);
1279 /* The thread with id has not been spawned yet,
1280 * so delegate the work to the main thread and
1281 * try spawning a new thread.
1282 */
1283 id = 0;
1284 spin_lock_irqsave(&iocq[id].lock, flags);
1285 }
1286 list_add_tail(new: &f->head, head: &iocq[id].head);
1287 spin_unlock_irqrestore(lock: &iocq[id].lock, flags);
1288 wake_up(&ktiowq[id]);
1289}
1290
1291struct sk_buff *
1292aoecmd_ata_rsp(struct sk_buff *skb)
1293{
1294 struct aoedev *d;
1295 struct aoe_hdr *h;
1296 struct frame *f;
1297 u32 n;
1298 ulong flags;
1299 char ebuf[128];
1300 u16 aoemajor;
1301
1302 h = (struct aoe_hdr *) skb->data;
1303 aoemajor = be16_to_cpu(get_unaligned(&h->major));
1304 d = aoedev_by_aoeaddr(maj: aoemajor, min: h->minor, do_alloc: 0);
1305 if (d == NULL) {
1306 snprintf(buf: ebuf, size: sizeof ebuf, fmt: "aoecmd_ata_rsp: ata response "
1307 "for unknown device %d.%d\n",
1308 aoemajor, h->minor);
1309 aoechr_error(ebuf);
1310 return skb;
1311 }
1312
1313 spin_lock_irqsave(&d->lock, flags);
1314
1315 n = be32_to_cpu(get_unaligned(&h->tag));
1316 f = getframe(d, tag: n);
1317 if (f) {
1318 calc_rttavg(d, t: f->t, rtt: tsince_hr(f));
1319 f->t->nout--;
1320 if (f->flags & FFL_PROBE)
1321 f->t->nout_probes--;
1322 } else {
1323 f = getframe_deferred(d, tag: n);
1324 if (f) {
1325 calc_rttavg(d, NULL, rtt: tsince_hr(f));
1326 } else {
1327 calc_rttavg(d, NULL, rtt: tsince(tag: n));
1328 spin_unlock_irqrestore(lock: &d->lock, flags);
1329 aoedev_put(d);
1330 snprintf(buf: ebuf, size: sizeof(ebuf),
1331 fmt: "%15s e%d.%d tag=%08x@%08lx s=%pm d=%pm\n",
1332 "unexpected rsp",
1333 get_unaligned_be16(p: &h->major),
1334 h->minor,
1335 get_unaligned_be32(p: &h->tag),
1336 jiffies,
1337 h->src,
1338 h->dst);
1339 aoechr_error(ebuf);
1340 return skb;
1341 }
1342 }
1343 aoecmd_work(d);
1344
1345 spin_unlock_irqrestore(lock: &d->lock, flags);
1346
1347 ktcomplete(f, skb);
1348
1349 /*
1350 * Note here that we do not perform an aoedev_put, as we are
1351 * leaving this reference for the ktio to release.
1352 */
1353 return NULL;
1354}
1355
1356void
1357aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
1358{
1359 struct sk_buff_head queue;
1360
1361 __skb_queue_head_init(list: &queue);
1362 aoecmd_cfg_pkts(aoemajor, aoeminor, queue: &queue);
1363 aoenet_xmit(&queue);
1364}
1365
1366struct sk_buff *
1367aoecmd_ata_id(struct aoedev *d)
1368{
1369 struct aoe_hdr *h;
1370 struct aoe_atahdr *ah;
1371 struct frame *f;
1372 struct sk_buff *skb;
1373 struct aoetgt *t;
1374
1375 f = newframe(d);
1376 if (f == NULL)
1377 return NULL;
1378
1379 t = *d->tgt;
1380
1381 /* initialize the headers & frame */
1382 skb = f->skb;
1383 h = (struct aoe_hdr *) skb_mac_header(skb);
1384 ah = (struct aoe_atahdr *) (h+1);
1385 skb_put(skb, len: sizeof *h + sizeof *ah);
1386 memset(h, 0, skb->len);
1387 f->tag = aoehdr_atainit(d, t, h);
1388 fhash(f);
1389 t->nout++;
1390 f->waited = 0;
1391 f->waited_total = 0;
1392
1393 /* set up ata header */
1394 ah->scnt = 1;
1395 ah->cmdstat = ATA_CMD_ID_ATA;
1396 ah->lba3 = 0xa0;
1397
1398 skb->dev = t->ifp->nd;
1399
1400 d->rttavg = RTTAVG_INIT;
1401 d->rttdev = RTTDEV_INIT;
1402 d->timer.function = rexmit_timer;
1403
1404 skb = skb_clone(skb, GFP_ATOMIC);
1405 if (skb)
1406 f->sent = ktime_get();
1407
1408 return skb;
1409}
1410
1411static struct aoetgt **
1412grow_targets(struct aoedev *d)
1413{
1414 ulong oldn, newn;
1415 struct aoetgt **tt;
1416
1417 oldn = d->ntargets;
1418 newn = oldn * 2;
1419 tt = kcalloc(n: newn, size: sizeof(*d->targets), GFP_ATOMIC);
1420 if (!tt)
1421 return NULL;
1422 memmove(tt, d->targets, sizeof(*d->targets) * oldn);
1423 d->tgt = tt + (d->tgt - d->targets);
1424 kfree(objp: d->targets);
1425 d->targets = tt;
1426 d->ntargets = newn;
1427
1428 return &d->targets[oldn];
1429}
1430
1431static struct aoetgt *
1432addtgt(struct aoedev *d, char *addr, ulong nframes)
1433{
1434 struct aoetgt *t, **tt, **te;
1435
1436 tt = d->targets;
1437 te = tt + d->ntargets;
1438 for (; tt < te && *tt; tt++)
1439 ;
1440
1441 if (tt == te) {
1442 tt = grow_targets(d);
1443 if (!tt)
1444 goto nomem;
1445 }
1446 t = kzalloc(size: sizeof(*t), GFP_ATOMIC);
1447 if (!t)
1448 goto nomem;
1449 t->nframes = nframes;
1450 t->d = d;
1451 memcpy(t->addr, addr, sizeof t->addr);
1452 t->ifp = t->ifs;
1453 aoecmd_wreset(t);
1454 t->maxout = t->nframes / 2;
1455 INIT_LIST_HEAD(list: &t->ffree);
1456 return *tt = t;
1457
1458 nomem:
1459 pr_info("aoe: cannot allocate memory to add target\n");
1460 return NULL;
1461}
1462
1463static void
1464setdbcnt(struct aoedev *d)
1465{
1466 struct aoetgt **t, **e;
1467 int bcnt = 0;
1468
1469 t = d->targets;
1470 e = t + d->ntargets;
1471 for (; t < e && *t; t++)
1472 if (bcnt == 0 || bcnt > (*t)->minbcnt)
1473 bcnt = (*t)->minbcnt;
1474 if (bcnt != d->maxbcnt) {
1475 d->maxbcnt = bcnt;
1476 pr_info("aoe: e%ld.%d: setting %d byte data frames\n",
1477 d->aoemajor, d->aoeminor, bcnt);
1478 }
1479}
1480
1481static void
1482setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt)
1483{
1484 struct aoedev *d;
1485 struct aoeif *p, *e;
1486 int minbcnt;
1487
1488 d = t->d;
1489 minbcnt = bcnt;
1490 p = t->ifs;
1491 e = p + NAOEIFS;
1492 for (; p < e; p++) {
1493 if (p->nd == NULL)
1494 break; /* end of the valid interfaces */
1495 if (p->nd == nd) {
1496 p->bcnt = bcnt; /* we're updating */
1497 nd = NULL;
1498 } else if (minbcnt > p->bcnt)
1499 minbcnt = p->bcnt; /* find the min interface */
1500 }
1501 if (nd) {
1502 if (p == e) {
1503 pr_err("aoe: device setifbcnt failure; too many interfaces.\n");
1504 return;
1505 }
1506 dev_hold(dev: nd);
1507 p->nd = nd;
1508 p->bcnt = bcnt;
1509 }
1510 t->minbcnt = minbcnt;
1511 setdbcnt(d);
1512}
1513
1514void
1515aoecmd_cfg_rsp(struct sk_buff *skb)
1516{
1517 struct aoedev *d;
1518 struct aoe_hdr *h;
1519 struct aoe_cfghdr *ch;
1520 struct aoetgt *t;
1521 ulong flags, aoemajor;
1522 struct sk_buff *sl;
1523 struct sk_buff_head queue;
1524 u16 n;
1525
1526 sl = NULL;
1527 h = (struct aoe_hdr *) skb_mac_header(skb);
1528 ch = (struct aoe_cfghdr *) (h+1);
1529
1530 /*
1531 * Enough people have their dip switches set backwards to
1532 * warrant a loud message for this special case.
1533 */
1534 aoemajor = get_unaligned_be16(p: &h->major);
1535 if (aoemajor == 0xfff) {
1536 printk(KERN_ERR "aoe: Warning: shelf address is all ones. "
1537 "Check shelf dip switches.\n");
1538 return;
1539 }
1540 if (aoemajor == 0xffff) {
1541 pr_info("aoe: e%ld.%d: broadcast shelf number invalid\n",
1542 aoemajor, (int) h->minor);
1543 return;
1544 }
1545 if (h->minor == 0xff) {
1546 pr_info("aoe: e%ld.%d: broadcast slot number invalid\n",
1547 aoemajor, (int) h->minor);
1548 return;
1549 }
1550
1551 n = be16_to_cpu(ch->bufcnt);
1552 if (n > aoe_maxout) /* keep it reasonable */
1553 n = aoe_maxout;
1554
1555 d = aoedev_by_aoeaddr(maj: aoemajor, min: h->minor, do_alloc: 1);
1556 if (d == NULL) {
1557 pr_info("aoe: device allocation failure\n");
1558 return;
1559 }
1560
1561 spin_lock_irqsave(&d->lock, flags);
1562
1563 t = gettgt(d, addr: h->src);
1564 if (t) {
1565 t->nframes = n;
1566 if (n < t->maxout)
1567 aoecmd_wreset(t);
1568 } else {
1569 t = addtgt(d, addr: h->src, nframes: n);
1570 if (!t)
1571 goto bail;
1572 }
1573 n = skb->dev->mtu;
1574 n -= sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr);
1575 n /= 512;
1576 if (n > ch->scnt)
1577 n = ch->scnt;
1578 n = n ? n * 512 : DEFAULTBCNT;
1579 setifbcnt(t, nd: skb->dev, bcnt: n);
1580
1581 /* don't change users' perspective */
1582 if (d->nopen == 0) {
1583 d->fw_ver = be16_to_cpu(ch->fwver);
1584 sl = aoecmd_ata_id(d);
1585 }
1586bail:
1587 spin_unlock_irqrestore(lock: &d->lock, flags);
1588 aoedev_put(d);
1589 if (sl) {
1590 __skb_queue_head_init(list: &queue);
1591 __skb_queue_tail(list: &queue, newsk: sl);
1592 aoenet_xmit(&queue);
1593 }
1594}
1595
1596void
1597aoecmd_wreset(struct aoetgt *t)
1598{
1599 t->maxout = 1;
1600 t->ssthresh = t->nframes / 2;
1601 t->next_cwnd = t->nframes;
1602}
1603
1604void
1605aoecmd_cleanslate(struct aoedev *d)
1606{
1607 struct aoetgt **t, **te;
1608
1609 d->rttavg = RTTAVG_INIT;
1610 d->rttdev = RTTDEV_INIT;
1611 d->maxbcnt = 0;
1612
1613 t = d->targets;
1614 te = t + d->ntargets;
1615 for (; t < te && *t; t++)
1616 aoecmd_wreset(t: *t);
1617}
1618
1619void
1620aoe_failbuf(struct aoedev *d, struct buf *buf)
1621{
1622 if (buf == NULL)
1623 return;
1624 buf->iter.bi_size = 0;
1625 buf->bio->bi_status = BLK_STS_IOERR;
1626 if (buf->nframesout == 0)
1627 aoe_end_buf(d, buf);
1628}
1629
1630void
1631aoe_flush_iocq(void)
1632{
1633 int i;
1634
1635 for (i = 0; i < ncpus; i++) {
1636 if (kts[i].active)
1637 aoe_flush_iocq_by_index(i);
1638 }
1639}
1640
1641void
1642aoe_flush_iocq_by_index(int id)
1643{
1644 struct frame *f;
1645 struct aoedev *d;
1646 LIST_HEAD(flist);
1647 struct list_head *pos;
1648 struct sk_buff *skb;
1649 ulong flags;
1650
1651 spin_lock_irqsave(&iocq[id].lock, flags);
1652 list_splice_init(list: &iocq[id].head, head: &flist);
1653 spin_unlock_irqrestore(lock: &iocq[id].lock, flags);
1654 while (!list_empty(head: &flist)) {
1655 pos = flist.next;
1656 list_del(entry: pos);
1657 f = list_entry(pos, struct frame, head);
1658 d = f->t->d;
1659 skb = f->r_skb;
1660 spin_lock_irqsave(&d->lock, flags);
1661 if (f->buf) {
1662 f->buf->nframesout--;
1663 aoe_failbuf(d, buf: f->buf);
1664 }
1665 aoe_freetframe(f);
1666 spin_unlock_irqrestore(lock: &d->lock, flags);
1667 dev_kfree_skb(skb);
1668 aoedev_put(d);
1669 }
1670}
1671
1672int __init
1673aoecmd_init(void)
1674{
1675 void *p;
1676 int i;
1677 int ret;
1678
1679 /* get_zeroed_page returns page with ref count 1 */
1680 p = (void *) get_zeroed_page(GFP_KERNEL);
1681 if (!p)
1682 return -ENOMEM;
1683 empty_page = virt_to_page(p);
1684
1685 ncpus = num_online_cpus();
1686
1687 iocq = kcalloc(n: ncpus, size: sizeof(struct iocq_ktio), GFP_KERNEL);
1688 if (!iocq)
1689 return -ENOMEM;
1690
1691 kts = kcalloc(n: ncpus, size: sizeof(struct ktstate), GFP_KERNEL);
1692 if (!kts) {
1693 ret = -ENOMEM;
1694 goto kts_fail;
1695 }
1696
1697 ktiowq = kcalloc(n: ncpus, size: sizeof(wait_queue_head_t), GFP_KERNEL);
1698 if (!ktiowq) {
1699 ret = -ENOMEM;
1700 goto ktiowq_fail;
1701 }
1702
1703 for (i = 0; i < ncpus; i++) {
1704 INIT_LIST_HEAD(list: &iocq[i].head);
1705 spin_lock_init(&iocq[i].lock);
1706 init_waitqueue_head(&ktiowq[i]);
1707 snprintf(buf: kts[i].name, size: sizeof(kts[i].name), fmt: "aoe_ktio%d", i);
1708 kts[i].fn = ktio;
1709 kts[i].waitq = &ktiowq[i];
1710 kts[i].lock = &iocq[i].lock;
1711 kts[i].id = i;
1712 kts[i].active = 0;
1713 }
1714 kts[0].active = 1;
1715 if (aoe_ktstart(k: &kts[0])) {
1716 ret = -ENOMEM;
1717 goto ktstart_fail;
1718 }
1719 return 0;
1720
1721ktstart_fail:
1722 kfree(objp: ktiowq);
1723ktiowq_fail:
1724 kfree(objp: kts);
1725kts_fail:
1726 kfree(objp: iocq);
1727
1728 return ret;
1729}
1730
1731void
1732aoecmd_exit(void)
1733{
1734 int i;
1735
1736 for (i = 0; i < ncpus; i++)
1737 if (kts[i].active)
1738 aoe_ktstop(k: &kts[i]);
1739
1740 aoe_flush_iocq();
1741
1742 /* Free up the iocq and thread speicific configuration
1743 * allocated during startup.
1744 */
1745 kfree(objp: iocq);
1746 kfree(objp: kts);
1747 kfree(objp: ktiowq);
1748
1749 free_page((unsigned long) page_address(empty_page));
1750 empty_page = NULL;
1751}
1752

source code of linux/drivers/block/aoe/aoecmd.c