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/genhd.h>
14 #include <linux/moduleparam.h>
15 #include <linux/workqueue.h>
16 #include <linux/kthread.h>
17 #include <net/net_namespace.h>
18 #include <asm/unaligned.h>
19 #include <linux/uio.h>
20 #include "aoe.h"
21
22 #define MAXIOC (8192) /* default meant to avoid most soft lockups */
23
24 static void ktcomplete(struct frame *, struct sk_buff *);
25 static int count_targets(struct aoedev *d, int *untainted);
26
27 static struct buf *nextbuf(struct aoedev *);
28
29 static int aoe_deadsecs = 60 * 3;
30 module_param(aoe_deadsecs, int, 0644);
31 MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev.");
32
33 static int aoe_maxout = 64;
34 module_param(aoe_maxout, int, 0644);
35 MODULE_PARM_DESC(aoe_maxout,
36 "Only aoe_maxout outstanding packets for every MAC on eX.Y.");
37
38 /* The number of online cpus during module initialization gives us a
39 * convenient heuristic cap on the parallelism used for ktio threads
40 * doing I/O completion. It is not important that the cap equal the
41 * actual number of running CPUs at any given time, but because of CPU
42 * hotplug, we take care to use ncpus instead of using
43 * num_online_cpus() after module initialization.
44 */
45 static int ncpus;
46
47 /* mutex lock used for synchronization while thread spawning */
48 static DEFINE_MUTEX(ktio_spawn_lock);
49
50 static wait_queue_head_t *ktiowq;
51 static struct ktstate *kts;
52
53 /* io completion queue */
54 struct iocq_ktio {
55 struct list_head head;
56 spinlock_t lock;
57 };
58 static struct iocq_ktio *iocq;
59
60 static struct page *empty_page;
61
62 static struct sk_buff *
new_skb(ulong len)63 new_skb(ulong len)
64 {
65 struct sk_buff *skb;
66
67 skb = alloc_skb(len + MAX_HEADER, GFP_ATOMIC);
68 if (skb) {
69 skb_reserve(skb, MAX_HEADER);
70 skb_reset_mac_header(skb);
71 skb_reset_network_header(skb);
72 skb->protocol = __constant_htons(ETH_P_AOE);
73 skb_checksum_none_assert(skb);
74 }
75 return skb;
76 }
77
78 static struct frame *
getframe_deferred(struct aoedev * d,u32 tag)79 getframe_deferred(struct aoedev *d, u32 tag)
80 {
81 struct list_head *head, *pos, *nx;
82 struct frame *f;
83
84 head = &d->rexmitq;
85 list_for_each_safe(pos, nx, head) {
86 f = list_entry(pos, struct frame, head);
87 if (f->tag == tag) {
88 list_del(pos);
89 return f;
90 }
91 }
92 return NULL;
93 }
94
95 static struct frame *
getframe(struct aoedev * d,u32 tag)96 getframe(struct aoedev *d, u32 tag)
97 {
98 struct frame *f;
99 struct list_head *head, *pos, *nx;
100 u32 n;
101
102 n = tag % NFACTIVE;
103 head = &d->factive[n];
104 list_for_each_safe(pos, nx, head) {
105 f = list_entry(pos, struct frame, head);
106 if (f->tag == tag) {
107 list_del(pos);
108 return f;
109 }
110 }
111 return NULL;
112 }
113
114 /*
115 * Leave the top bit clear so we have tagspace for userland.
116 * The bottom 16 bits are the xmit tick for rexmit/rttavg processing.
117 * This driver reserves tag -1 to mean "unused frame."
118 */
119 static int
newtag(struct aoedev * d)120 newtag(struct aoedev *d)
121 {
122 register ulong n;
123
124 n = jiffies & 0xffff;
125 return n |= (++d->lasttag & 0x7fff) << 16;
126 }
127
128 static u32
aoehdr_atainit(struct aoedev * d,struct aoetgt * t,struct aoe_hdr * h)129 aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)
130 {
131 u32 host_tag = newtag(d);
132
133 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
134 memcpy(h->dst, t->addr, sizeof h->dst);
135 h->type = __constant_cpu_to_be16(ETH_P_AOE);
136 h->verfl = AOE_HVER;
137 h->major = cpu_to_be16(d->aoemajor);
138 h->minor = d->aoeminor;
139 h->cmd = AOECMD_ATA;
140 h->tag = cpu_to_be32(host_tag);
141
142 return host_tag;
143 }
144
145 static inline void
put_lba(struct aoe_atahdr * ah,sector_t lba)146 put_lba(struct aoe_atahdr *ah, sector_t lba)
147 {
148 ah->lba0 = lba;
149 ah->lba1 = lba >>= 8;
150 ah->lba2 = lba >>= 8;
151 ah->lba3 = lba >>= 8;
152 ah->lba4 = lba >>= 8;
153 ah->lba5 = lba >>= 8;
154 }
155
156 static struct aoeif *
ifrotate(struct aoetgt * t)157 ifrotate(struct aoetgt *t)
158 {
159 struct aoeif *ifp;
160
161 ifp = t->ifp;
162 ifp++;
163 if (ifp >= &t->ifs[NAOEIFS] || ifp->nd == NULL)
164 ifp = t->ifs;
165 if (ifp->nd == NULL)
166 return NULL;
167 return t->ifp = ifp;
168 }
169
170 static void
skb_pool_put(struct aoedev * d,struct sk_buff * skb)171 skb_pool_put(struct aoedev *d, struct sk_buff *skb)
172 {
173 __skb_queue_tail(&d->skbpool, skb);
174 }
175
176 static struct sk_buff *
skb_pool_get(struct aoedev * d)177 skb_pool_get(struct aoedev *d)
178 {
179 struct sk_buff *skb = skb_peek(&d->skbpool);
180
181 if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) {
182 __skb_unlink(skb, &d->skbpool);
183 return skb;
184 }
185 if (skb_queue_len(&d->skbpool) < NSKBPOOLMAX &&
186 (skb = new_skb(ETH_ZLEN)))
187 return skb;
188
189 return NULL;
190 }
191
192 void
aoe_freetframe(struct frame * f)193 aoe_freetframe(struct frame *f)
194 {
195 struct aoetgt *t;
196
197 t = f->t;
198 f->buf = NULL;
199 memset(&f->iter, 0, sizeof(f->iter));
200 f->r_skb = NULL;
201 f->flags = 0;
202 list_add(&f->head, &t->ffree);
203 }
204
205 static struct frame *
newtframe(struct aoedev * d,struct aoetgt * t)206 newtframe(struct aoedev *d, struct aoetgt *t)
207 {
208 struct frame *f;
209 struct sk_buff *skb;
210 struct list_head *pos;
211
212 if (list_empty(&t->ffree)) {
213 if (t->falloc >= NSKBPOOLMAX*2)
214 return NULL;
215 f = kcalloc(1, sizeof(*f), GFP_ATOMIC);
216 if (f == NULL)
217 return NULL;
218 t->falloc++;
219 f->t = t;
220 } else {
221 pos = t->ffree.next;
222 list_del(pos);
223 f = list_entry(pos, struct frame, head);
224 }
225
226 skb = f->skb;
227 if (skb == NULL) {
228 f->skb = skb = new_skb(ETH_ZLEN);
229 if (!skb) {
230 bail: aoe_freetframe(f);
231 return NULL;
232 }
233 }
234
235 if (atomic_read(&skb_shinfo(skb)->dataref) != 1) {
236 skb = skb_pool_get(d);
237 if (skb == NULL)
238 goto bail;
239 skb_pool_put(d, f->skb);
240 f->skb = skb;
241 }
242
243 skb->truesize -= skb->data_len;
244 skb_shinfo(skb)->nr_frags = skb->data_len = 0;
245 skb_trim(skb, 0);
246 return f;
247 }
248
249 static struct frame *
newframe(struct aoedev * d)250 newframe(struct aoedev *d)
251 {
252 struct frame *f;
253 struct aoetgt *t, **tt;
254 int totout = 0;
255 int use_tainted;
256 int has_untainted;
257
258 if (!d->targets || !d->targets[0]) {
259 printk(KERN_ERR "aoe: NULL TARGETS!\n");
260 return NULL;
261 }
262 tt = d->tgt; /* last used target */
263 for (use_tainted = 0, has_untainted = 0;;) {
264 tt++;
265 if (tt >= &d->targets[d->ntargets] || !*tt)
266 tt = d->targets;
267 t = *tt;
268 if (!t->taint) {
269 has_untainted = 1;
270 totout += t->nout;
271 }
272 if (t->nout < t->maxout
273 && (use_tainted || !t->taint)
274 && t->ifp->nd) {
275 f = newtframe(d, t);
276 if (f) {
277 ifrotate(t);
278 d->tgt = tt;
279 return f;
280 }
281 }
282 if (tt == d->tgt) { /* we've looped and found nada */
283 if (!use_tainted && !has_untainted)
284 use_tainted = 1;
285 else
286 break;
287 }
288 }
289 if (totout == 0) {
290 d->kicked++;
291 d->flags |= DEVFL_KICKME;
292 }
293 return NULL;
294 }
295
296 static void
skb_fillup(struct sk_buff * skb,struct bio * bio,struct bvec_iter iter)297 skb_fillup(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter)
298 {
299 int frag = 0;
300 struct bio_vec bv;
301
302 __bio_for_each_segment(bv, bio, iter, iter)
303 skb_fill_page_desc(skb, frag++, bv.bv_page,
304 bv.bv_offset, bv.bv_len);
305 }
306
307 static void
fhash(struct frame * f)308 fhash(struct frame *f)
309 {
310 struct aoedev *d = f->t->d;
311 u32 n;
312
313 n = f->tag % NFACTIVE;
314 list_add_tail(&f->head, &d->factive[n]);
315 }
316
317 static void
ata_rw_frameinit(struct frame * f)318 ata_rw_frameinit(struct frame *f)
319 {
320 struct aoetgt *t;
321 struct aoe_hdr *h;
322 struct aoe_atahdr *ah;
323 struct sk_buff *skb;
324 char writebit, extbit;
325
326 skb = f->skb;
327 h = (struct aoe_hdr *) skb_mac_header(skb);
328 ah = (struct aoe_atahdr *) (h + 1);
329 skb_put(skb, sizeof(*h) + sizeof(*ah));
330 memset(h, 0, skb->len);
331
332 writebit = 0x10;
333 extbit = 0x4;
334
335 t = f->t;
336 f->tag = aoehdr_atainit(t->d, t, h);
337 fhash(f);
338 t->nout++;
339 f->waited = 0;
340 f->waited_total = 0;
341
342 /* set up ata header */
343 ah->scnt = f->iter.bi_size >> 9;
344 put_lba(ah, f->iter.bi_sector);
345 if (t->d->flags & DEVFL_EXT) {
346 ah->aflags |= AOEAFL_EXT;
347 } else {
348 extbit = 0;
349 ah->lba3 &= 0x0f;
350 ah->lba3 |= 0xe0; /* LBA bit + obsolete 0xa0 */
351 }
352 if (f->buf && bio_data_dir(f->buf->bio) == WRITE) {
353 skb_fillup(skb, f->buf->bio, f->iter);
354 ah->aflags |= AOEAFL_WRITE;
355 skb->len += f->iter.bi_size;
356 skb->data_len = f->iter.bi_size;
357 skb->truesize += f->iter.bi_size;
358 t->wpkts++;
359 } else {
360 t->rpkts++;
361 writebit = 0;
362 }
363
364 ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit;
365 skb->dev = t->ifp->nd;
366 }
367
368 static int
aoecmd_ata_rw(struct aoedev * d)369 aoecmd_ata_rw(struct aoedev *d)
370 {
371 struct frame *f;
372 struct buf *buf;
373 struct sk_buff *skb;
374 struct sk_buff_head queue;
375
376 buf = nextbuf(d);
377 if (buf == NULL)
378 return 0;
379 f = newframe(d);
380 if (f == NULL)
381 return 0;
382
383 /* initialize the headers & frame */
384 f->buf = buf;
385 f->iter = buf->iter;
386 f->iter.bi_size = min_t(unsigned long,
387 d->maxbcnt ?: DEFAULTBCNT,
388 f->iter.bi_size);
389 bio_advance_iter(buf->bio, &buf->iter, f->iter.bi_size);
390
391 if (!buf->iter.bi_size)
392 d->ip.buf = NULL;
393
394 /* mark all tracking fields and load out */
395 buf->nframesout += 1;
396
397 ata_rw_frameinit(f);
398
399 skb = skb_clone(f->skb, GFP_ATOMIC);
400 if (skb) {
401 f->sent = ktime_get();
402 __skb_queue_head_init(&queue);
403 __skb_queue_tail(&queue, skb);
404 aoenet_xmit(&queue);
405 }
406 return 1;
407 }
408
409 /* some callers cannot sleep, and they can call this function,
410 * transmitting the packets later, when interrupts are on
411 */
412 static void
aoecmd_cfg_pkts(ushort aoemajor,unsigned char aoeminor,struct sk_buff_head * queue)413 aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue)
414 {
415 struct aoe_hdr *h;
416 struct aoe_cfghdr *ch;
417 struct sk_buff *skb;
418 struct net_device *ifp;
419
420 rcu_read_lock();
421 for_each_netdev_rcu(&init_net, ifp) {
422 dev_hold(ifp);
423 if (!is_aoe_netif(ifp))
424 goto cont;
425
426 skb = new_skb(sizeof *h + sizeof *ch);
427 if (skb == NULL) {
428 printk(KERN_INFO "aoe: skb alloc failure\n");
429 goto cont;
430 }
431 skb_put(skb, sizeof *h + sizeof *ch);
432 skb->dev = ifp;
433 __skb_queue_tail(queue, skb);
434 h = (struct aoe_hdr *) skb_mac_header(skb);
435 memset(h, 0, sizeof *h + sizeof *ch);
436
437 memset(h->dst, 0xff, sizeof h->dst);
438 memcpy(h->src, ifp->dev_addr, sizeof h->src);
439 h->type = __constant_cpu_to_be16(ETH_P_AOE);
440 h->verfl = AOE_HVER;
441 h->major = cpu_to_be16(aoemajor);
442 h->minor = aoeminor;
443 h->cmd = AOECMD_CFG;
444
445 cont:
446 dev_put(ifp);
447 }
448 rcu_read_unlock();
449 }
450
451 static void
resend(struct aoedev * d,struct frame * f)452 resend(struct aoedev *d, struct frame *f)
453 {
454 struct sk_buff *skb;
455 struct sk_buff_head queue;
456 struct aoe_hdr *h;
457 struct aoetgt *t;
458 char buf[128];
459 u32 n;
460
461 t = f->t;
462 n = newtag(d);
463 skb = f->skb;
464 if (ifrotate(t) == NULL) {
465 /* probably can't happen, but set it up to fail anyway */
466 pr_info("aoe: resend: no interfaces to rotate to.\n");
467 ktcomplete(f, NULL);
468 return;
469 }
470 h = (struct aoe_hdr *) skb_mac_header(skb);
471
472 if (!(f->flags & FFL_PROBE)) {
473 snprintf(buf, sizeof(buf),
474 "%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n",
475 "retransmit", d->aoemajor, d->aoeminor,
476 f->tag, jiffies, n,
477 h->src, h->dst, t->nout);
478 aoechr_error(buf);
479 }
480
481 f->tag = n;
482 fhash(f);
483 h->tag = cpu_to_be32(n);
484 memcpy(h->dst, t->addr, sizeof h->dst);
485 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
486
487 skb->dev = t->ifp->nd;
488 skb = skb_clone(skb, GFP_ATOMIC);
489 if (skb == NULL)
490 return;
491 f->sent = ktime_get();
492 __skb_queue_head_init(&queue);
493 __skb_queue_tail(&queue, skb);
494 aoenet_xmit(&queue);
495 }
496
497 static int
tsince_hr(struct frame * f)498 tsince_hr(struct frame *f)
499 {
500 u64 delta = ktime_to_ns(ktime_sub(ktime_get(), f->sent));
501
502 /* delta is normally under 4.2 seconds, avoid 64-bit division */
503 if (likely(delta <= UINT_MAX))
504 return (u32)delta / NSEC_PER_USEC;
505
506 /* avoid overflow after 71 minutes */
507 if (delta > ((u64)INT_MAX * NSEC_PER_USEC))
508 return INT_MAX;
509
510 return div_u64(delta, NSEC_PER_USEC);
511 }
512
513 static int
tsince(u32 tag)514 tsince(u32 tag)
515 {
516 int n;
517
518 n = jiffies & 0xffff;
519 n -= tag & 0xffff;
520 if (n < 0)
521 n += 1<<16;
522 return jiffies_to_usecs(n + 1);
523 }
524
525 static struct aoeif *
getif(struct aoetgt * t,struct net_device * nd)526 getif(struct aoetgt *t, struct net_device *nd)
527 {
528 struct aoeif *p, *e;
529
530 p = t->ifs;
531 e = p + NAOEIFS;
532 for (; p < e; p++)
533 if (p->nd == nd)
534 return p;
535 return NULL;
536 }
537
538 static void
ejectif(struct aoetgt * t,struct aoeif * ifp)539 ejectif(struct aoetgt *t, struct aoeif *ifp)
540 {
541 struct aoeif *e;
542 struct net_device *nd;
543 ulong n;
544
545 nd = ifp->nd;
546 e = t->ifs + NAOEIFS - 1;
547 n = (e - ifp) * sizeof *ifp;
548 memmove(ifp, ifp+1, n);
549 e->nd = NULL;
550 dev_put(nd);
551 }
552
553 static struct frame *
reassign_frame(struct frame * f)554 reassign_frame(struct frame *f)
555 {
556 struct frame *nf;
557 struct sk_buff *skb;
558
559 nf = newframe(f->t->d);
560 if (!nf)
561 return NULL;
562 if (nf->t == f->t) {
563 aoe_freetframe(nf);
564 return NULL;
565 }
566
567 skb = nf->skb;
568 nf->skb = f->skb;
569 nf->buf = f->buf;
570 nf->iter = f->iter;
571 nf->waited = 0;
572 nf->waited_total = f->waited_total;
573 nf->sent = f->sent;
574 f->skb = skb;
575
576 return nf;
577 }
578
579 static void
probe(struct aoetgt * t)580 probe(struct aoetgt *t)
581 {
582 struct aoedev *d;
583 struct frame *f;
584 struct sk_buff *skb;
585 struct sk_buff_head queue;
586 size_t n, m;
587 int frag;
588
589 d = t->d;
590 f = newtframe(d, t);
591 if (!f) {
592 pr_err("%s %pm for e%ld.%d: %s\n",
593 "aoe: cannot probe remote address",
594 t->addr,
595 (long) d->aoemajor, d->aoeminor,
596 "no frame available");
597 return;
598 }
599 f->flags |= FFL_PROBE;
600 ifrotate(t);
601 f->iter.bi_size = t->d->maxbcnt ? t->d->maxbcnt : DEFAULTBCNT;
602 ata_rw_frameinit(f);
603 skb = f->skb;
604 for (frag = 0, n = f->iter.bi_size; n > 0; ++frag, n -= m) {
605 if (n < PAGE_SIZE)
606 m = n;
607 else
608 m = PAGE_SIZE;
609 skb_fill_page_desc(skb, frag, empty_page, 0, m);
610 }
611 skb->len += f->iter.bi_size;
612 skb->data_len = f->iter.bi_size;
613 skb->truesize += f->iter.bi_size;
614
615 skb = skb_clone(f->skb, GFP_ATOMIC);
616 if (skb) {
617 f->sent = ktime_get();
618 __skb_queue_head_init(&queue);
619 __skb_queue_tail(&queue, skb);
620 aoenet_xmit(&queue);
621 }
622 }
623
624 static long
rto(struct aoedev * d)625 rto(struct aoedev *d)
626 {
627 long t;
628
629 t = 2 * d->rttavg >> RTTSCALE;
630 t += 8 * d->rttdev >> RTTDSCALE;
631 if (t == 0)
632 t = 1;
633
634 return t;
635 }
636
637 static void
rexmit_deferred(struct aoedev * d)638 rexmit_deferred(struct aoedev *d)
639 {
640 struct aoetgt *t;
641 struct frame *f;
642 struct frame *nf;
643 struct list_head *pos, *nx, *head;
644 int since;
645 int untainted;
646
647 count_targets(d, &untainted);
648
649 head = &d->rexmitq;
650 list_for_each_safe(pos, nx, head) {
651 f = list_entry(pos, struct frame, head);
652 t = f->t;
653 if (t->taint) {
654 if (!(f->flags & FFL_PROBE)) {
655 nf = reassign_frame(f);
656 if (nf) {
657 if (t->nout_probes == 0
658 && untainted > 0) {
659 probe(t);
660 t->nout_probes++;
661 }
662 list_replace(&f->head, &nf->head);
663 pos = &nf->head;
664 aoe_freetframe(f);
665 f = nf;
666 t = f->t;
667 }
668 } else if (untainted < 1) {
669 /* don't probe w/o other untainted aoetgts */
670 goto stop_probe;
671 } else if (tsince_hr(f) < t->taint * rto(d)) {
672 /* reprobe slowly when taint is high */
673 continue;
674 }
675 } else if (f->flags & FFL_PROBE) {
676 stop_probe: /* don't probe untainted aoetgts */
677 list_del(pos);
678 aoe_freetframe(f);
679 /* leaving d->kicked, because this is routine */
680 f->t->d->flags |= DEVFL_KICKME;
681 continue;
682 }
683 if (t->nout >= t->maxout)
684 continue;
685 list_del(pos);
686 t->nout++;
687 if (f->flags & FFL_PROBE)
688 t->nout_probes++;
689 since = tsince_hr(f);
690 f->waited += since;
691 f->waited_total += since;
692 resend(d, f);
693 }
694 }
695
696 /* An aoetgt accumulates demerits quickly, and successful
697 * probing redeems the aoetgt slowly.
698 */
699 static void
scorn(struct aoetgt * t)700 scorn(struct aoetgt *t)
701 {
702 int n;
703
704 n = t->taint++;
705 t->taint += t->taint * 2;
706 if (n > t->taint)
707 t->taint = n;
708 if (t->taint > MAX_TAINT)
709 t->taint = MAX_TAINT;
710 }
711
712 static int
count_targets(struct aoedev * d,int * untainted)713 count_targets(struct aoedev *d, int *untainted)
714 {
715 int i, good;
716
717 for (i = good = 0; i < d->ntargets && d->targets[i]; ++i)
718 if (d->targets[i]->taint == 0)
719 good++;
720
721 if (untainted)
722 *untainted = good;
723 return i;
724 }
725
726 static void
rexmit_timer(struct timer_list * timer)727 rexmit_timer(struct timer_list *timer)
728 {
729 struct aoedev *d;
730 struct aoetgt *t;
731 struct aoeif *ifp;
732 struct frame *f;
733 struct list_head *head, *pos, *nx;
734 LIST_HEAD(flist);
735 register long timeout;
736 ulong flags, n;
737 int i;
738 int utgts; /* number of aoetgt descriptors (not slots) */
739 int since;
740
741 d = from_timer(d, timer, timer);
742
743 spin_lock_irqsave(&d->lock, flags);
744
745 /* timeout based on observed timings and variations */
746 timeout = rto(d);
747
748 utgts = count_targets(d, NULL);
749
750 if (d->flags & DEVFL_TKILL) {
751 spin_unlock_irqrestore(&d->lock, flags);
752 return;
753 }
754
755 /* collect all frames to rexmit into flist */
756 for (i = 0; i < NFACTIVE; i++) {
757 head = &d->factive[i];
758 list_for_each_safe(pos, nx, head) {
759 f = list_entry(pos, struct frame, head);
760 if (tsince_hr(f) < timeout)
761 break; /* end of expired frames */
762 /* move to flist for later processing */
763 list_move_tail(pos, &flist);
764 }
765 }
766
767 /* process expired frames */
768 while (!list_empty(&flist)) {
769 pos = flist.next;
770 f = list_entry(pos, struct frame, head);
771 since = tsince_hr(f);
772 n = f->waited_total + since;
773 n /= USEC_PER_SEC;
774 if (aoe_deadsecs
775 && n > aoe_deadsecs
776 && !(f->flags & FFL_PROBE)) {
777 /* Waited too long. Device failure.
778 * Hang all frames on first hash bucket for downdev
779 * to clean up.
780 */
781 list_splice(&flist, &d->factive[0]);
782 aoedev_downdev(d);
783 goto out;
784 }
785
786 t = f->t;
787 n = f->waited + since;
788 n /= USEC_PER_SEC;
789 if (aoe_deadsecs && utgts > 0
790 && (n > aoe_deadsecs / utgts || n > HARD_SCORN_SECS))
791 scorn(t); /* avoid this target */
792
793 if (t->maxout != 1) {
794 t->ssthresh = t->maxout / 2;
795 t->maxout = 1;
796 }
797
798 if (f->flags & FFL_PROBE) {
799 t->nout_probes--;
800 } else {
801 ifp = getif(t, f->skb->dev);
802 if (ifp && ++ifp->lost > (t->nframes << 1)
803 && (ifp != t->ifs || t->ifs[1].nd)) {
804 ejectif(t, ifp);
805 ifp = NULL;
806 }
807 }
808 list_move_tail(pos, &d->rexmitq);
809 t->nout--;
810 }
811 rexmit_deferred(d);
812
813 out:
814 if ((d->flags & DEVFL_KICKME) && d->blkq) {
815 d->flags &= ~DEVFL_KICKME;
816 blk_mq_run_hw_queues(d->blkq, true);
817 }
818
819 d->timer.expires = jiffies + TIMERTICK;
820 add_timer(&d->timer);
821
822 spin_unlock_irqrestore(&d->lock, flags);
823 }
824
825 static void
bufinit(struct buf * buf,struct request * rq,struct bio * bio)826 bufinit(struct buf *buf, struct request *rq, struct bio *bio)
827 {
828 memset(buf, 0, sizeof(*buf));
829 buf->rq = rq;
830 buf->bio = bio;
831 buf->iter = bio->bi_iter;
832 }
833
834 static struct buf *
nextbuf(struct aoedev * d)835 nextbuf(struct aoedev *d)
836 {
837 struct request *rq;
838 struct request_queue *q;
839 struct aoe_req *req;
840 struct buf *buf;
841 struct bio *bio;
842
843 q = d->blkq;
844 if (q == NULL)
845 return NULL; /* initializing */
846 if (d->ip.buf)
847 return d->ip.buf;
848 rq = d->ip.rq;
849 if (rq == NULL) {
850 rq = list_first_entry_or_null(&d->rq_list, struct request,
851 queuelist);
852 if (rq == NULL)
853 return NULL;
854 list_del_init(&rq->queuelist);
855 blk_mq_start_request(rq);
856 d->ip.rq = rq;
857 d->ip.nxbio = rq->bio;
858
859 req = blk_mq_rq_to_pdu(rq);
860 req->nr_bios = 0;
861 __rq_for_each_bio(bio, rq)
862 req->nr_bios++;
863 }
864 buf = mempool_alloc(d->bufpool, GFP_ATOMIC);
865 if (buf == NULL) {
866 pr_err("aoe: nextbuf: unable to mempool_alloc!\n");
867 return NULL;
868 }
869 bio = d->ip.nxbio;
870 bufinit(buf, rq, bio);
871 bio = bio->bi_next;
872 d->ip.nxbio = bio;
873 if (bio == NULL)
874 d->ip.rq = NULL;
875 return d->ip.buf = buf;
876 }
877
878 /* enters with d->lock held */
879 void
aoecmd_work(struct aoedev * d)880 aoecmd_work(struct aoedev *d)
881 {
882 rexmit_deferred(d);
883 while (aoecmd_ata_rw(d))
884 ;
885 }
886
887 /* this function performs work that has been deferred until sleeping is OK
888 */
889 void
aoecmd_sleepwork(struct work_struct * work)890 aoecmd_sleepwork(struct work_struct *work)
891 {
892 struct aoedev *d = container_of(work, struct aoedev, work);
893
894 if (d->flags & DEVFL_GDALLOC)
895 aoeblk_gdalloc(d);
896
897 if (d->flags & DEVFL_NEWSIZE) {
898 set_capacity_and_notify(d->gd, d->ssize);
899
900 spin_lock_irq(&d->lock);
901 d->flags |= DEVFL_UP;
902 d->flags &= ~DEVFL_NEWSIZE;
903 spin_unlock_irq(&d->lock);
904 }
905 }
906
907 static void
ata_ident_fixstring(u16 * id,int ns)908 ata_ident_fixstring(u16 *id, int ns)
909 {
910 u16 s;
911
912 while (ns-- > 0) {
913 s = *id;
914 *id++ = s >> 8 | s << 8;
915 }
916 }
917
918 static void
ataid_complete(struct aoedev * d,struct aoetgt * t,unsigned char * id)919 ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
920 {
921 u64 ssize;
922 u16 n;
923
924 /* word 83: command set supported */
925 n = get_unaligned_le16(&id[83 << 1]);
926
927 /* word 86: command set/feature enabled */
928 n |= get_unaligned_le16(&id[86 << 1]);
929
930 if (n & (1<<10)) { /* bit 10: LBA 48 */
931 d->flags |= DEVFL_EXT;
932
933 /* word 100: number lba48 sectors */
934 ssize = get_unaligned_le64(&id[100 << 1]);
935
936 /* set as in ide-disk.c:init_idedisk_capacity */
937 d->geo.cylinders = ssize;
938 d->geo.cylinders /= (255 * 63);
939 d->geo.heads = 255;
940 d->geo.sectors = 63;
941 } else {
942 d->flags &= ~DEVFL_EXT;
943
944 /* number lba28 sectors */
945 ssize = get_unaligned_le32(&id[60 << 1]);
946
947 /* NOTE: obsolete in ATA 6 */
948 d->geo.cylinders = get_unaligned_le16(&id[54 << 1]);
949 d->geo.heads = get_unaligned_le16(&id[55 << 1]);
950 d->geo.sectors = get_unaligned_le16(&id[56 << 1]);
951 }
952
953 ata_ident_fixstring((u16 *) &id[10<<1], 10); /* serial */
954 ata_ident_fixstring((u16 *) &id[23<<1], 4); /* firmware */
955 ata_ident_fixstring((u16 *) &id[27<<1], 20); /* model */
956 memcpy(d->ident, id, sizeof(d->ident));
957
958 if (d->ssize != ssize)
959 printk(KERN_INFO
960 "aoe: %pm e%ld.%d v%04x has %llu sectors\n",
961 t->addr,
962 d->aoemajor, d->aoeminor,
963 d->fw_ver, (long long)ssize);
964 d->ssize = ssize;
965 d->geo.start = 0;
966 if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
967 return;
968 if (d->gd != NULL)
969 d->flags |= DEVFL_NEWSIZE;
970 else
971 d->flags |= DEVFL_GDALLOC;
972 schedule_work(&d->work);
973 }
974
975 static void
calc_rttavg(struct aoedev * d,struct aoetgt * t,int rtt)976 calc_rttavg(struct aoedev *d, struct aoetgt *t, int rtt)
977 {
978 register long n;
979
980 n = rtt;
981
982 /* cf. Congestion Avoidance and Control, Jacobson & Karels, 1988 */
983 n -= d->rttavg >> RTTSCALE;
984 d->rttavg += n;
985 if (n < 0)
986 n = -n;
987 n -= d->rttdev >> RTTDSCALE;
988 d->rttdev += n;
989
990 if (!t || t->maxout >= t->nframes)
991 return;
992 if (t->maxout < t->ssthresh)
993 t->maxout += 1;
994 else if (t->nout == t->maxout && t->next_cwnd-- == 0) {
995 t->maxout += 1;
996 t->next_cwnd = t->maxout;
997 }
998 }
999
1000 static struct aoetgt *
gettgt(struct aoedev * d,char * addr)1001 gettgt(struct aoedev *d, char *addr)
1002 {
1003 struct aoetgt **t, **e;
1004
1005 t = d->targets;
1006 e = t + d->ntargets;
1007 for (; t < e && *t; t++)
1008 if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0)
1009 return *t;
1010 return NULL;
1011 }
1012
1013 static void
bvcpy(struct sk_buff * skb,struct bio * bio,struct bvec_iter iter,long cnt)1014 bvcpy(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter, long cnt)
1015 {
1016 int soff = 0;
1017 struct bio_vec bv;
1018
1019 iter.bi_size = cnt;
1020
1021 __bio_for_each_segment(bv, bio, iter, iter) {
1022 char *p = kmap_atomic(bv.bv_page) + bv.bv_offset;
1023 skb_copy_bits(skb, soff, p, bv.bv_len);
1024 kunmap_atomic(p);
1025 soff += bv.bv_len;
1026 }
1027 }
1028
1029 void
aoe_end_request(struct aoedev * d,struct request * rq,int fastfail)1030 aoe_end_request(struct aoedev *d, struct request *rq, int fastfail)
1031 {
1032 struct bio *bio;
1033 int bok;
1034 struct request_queue *q;
1035 blk_status_t err = BLK_STS_OK;
1036
1037 q = d->blkq;
1038 if (rq == d->ip.rq)
1039 d->ip.rq = NULL;
1040 do {
1041 bio = rq->bio;
1042 bok = !fastfail && !bio->bi_status;
1043 if (!bok)
1044 err = BLK_STS_IOERR;
1045 } while (blk_update_request(rq, bok ? BLK_STS_OK : BLK_STS_IOERR, bio->bi_iter.bi_size));
1046
1047 __blk_mq_end_request(rq, err);
1048
1049 /* cf. https://lore.kernel.org/lkml/20061031071040.GS14055@kernel.dk/ */
1050 if (!fastfail)
1051 blk_mq_run_hw_queues(q, true);
1052 }
1053
1054 static void
aoe_end_buf(struct aoedev * d,struct buf * buf)1055 aoe_end_buf(struct aoedev *d, struct buf *buf)
1056 {
1057 struct request *rq = buf->rq;
1058 struct aoe_req *req = blk_mq_rq_to_pdu(rq);
1059
1060 if (buf == d->ip.buf)
1061 d->ip.buf = NULL;
1062 mempool_free(buf, d->bufpool);
1063 if (--req->nr_bios == 0)
1064 aoe_end_request(d, rq, 0);
1065 }
1066
1067 static void
ktiocomplete(struct frame * f)1068 ktiocomplete(struct frame *f)
1069 {
1070 struct aoe_hdr *hin, *hout;
1071 struct aoe_atahdr *ahin, *ahout;
1072 struct buf *buf;
1073 struct sk_buff *skb;
1074 struct aoetgt *t;
1075 struct aoeif *ifp;
1076 struct aoedev *d;
1077 long n;
1078 int untainted;
1079
1080 if (f == NULL)
1081 return;
1082
1083 t = f->t;
1084 d = t->d;
1085 skb = f->r_skb;
1086 buf = f->buf;
1087 if (f->flags & FFL_PROBE)
1088 goto out;
1089 if (!skb) /* just fail the buf. */
1090 goto noskb;
1091
1092 hout = (struct aoe_hdr *) skb_mac_header(f->skb);
1093 ahout = (struct aoe_atahdr *) (hout+1);
1094
1095 hin = (struct aoe_hdr *) skb->data;
1096 skb_pull(skb, sizeof(*hin));
1097 ahin = (struct aoe_atahdr *) skb->data;
1098 skb_pull(skb, sizeof(*ahin));
1099 if (ahin->cmdstat & 0xa9) { /* these bits cleared on success */
1100 pr_err("aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n",
1101 ahout->cmdstat, ahin->cmdstat,
1102 d->aoemajor, d->aoeminor);
1103 noskb: if (buf)
1104 buf->bio->bi_status = BLK_STS_IOERR;
1105 goto out;
1106 }
1107
1108 n = ahout->scnt << 9;
1109 switch (ahout->cmdstat) {
1110 case ATA_CMD_PIO_READ:
1111 case ATA_CMD_PIO_READ_EXT:
1112 if (skb->len < n) {
1113 pr_err("%s e%ld.%d. skb->len=%d need=%ld\n",
1114 "aoe: runt data size in read from",
1115 (long) d->aoemajor, d->aoeminor,
1116 skb->len, n);
1117 buf->bio->bi_status = BLK_STS_IOERR;
1118 break;
1119 }
1120 if (n > f->iter.bi_size) {
1121 pr_err_ratelimited("%s e%ld.%d. bytes=%ld need=%u\n",
1122 "aoe: too-large data size in read from",
1123 (long) d->aoemajor, d->aoeminor,
1124 n, f->iter.bi_size);
1125 buf->bio->bi_status = BLK_STS_IOERR;
1126 break;
1127 }
1128 bvcpy(skb, f->buf->bio, f->iter, n);
1129 fallthrough;
1130 case ATA_CMD_PIO_WRITE:
1131 case ATA_CMD_PIO_WRITE_EXT:
1132 spin_lock_irq(&d->lock);
1133 ifp = getif(t, skb->dev);
1134 if (ifp)
1135 ifp->lost = 0;
1136 spin_unlock_irq(&d->lock);
1137 break;
1138 case ATA_CMD_ID_ATA:
1139 if (skb->len < 512) {
1140 pr_info("%s e%ld.%d. skb->len=%d need=512\n",
1141 "aoe: runt data size in ataid from",
1142 (long) d->aoemajor, d->aoeminor,
1143 skb->len);
1144 break;
1145 }
1146 if (skb_linearize(skb))
1147 break;
1148 spin_lock_irq(&d->lock);
1149 ataid_complete(d, t, skb->data);
1150 spin_unlock_irq(&d->lock);
1151 break;
1152 default:
1153 pr_info("aoe: unrecognized ata command %2.2Xh for %d.%d\n",
1154 ahout->cmdstat,
1155 be16_to_cpu(get_unaligned(&hin->major)),
1156 hin->minor);
1157 }
1158 out:
1159 spin_lock_irq(&d->lock);
1160 if (t->taint > 0
1161 && --t->taint > 0
1162 && t->nout_probes == 0) {
1163 count_targets(d, &untainted);
1164 if (untainted > 0) {
1165 probe(t);
1166 t->nout_probes++;
1167 }
1168 }
1169
1170 aoe_freetframe(f);
1171
1172 if (buf && --buf->nframesout == 0 && buf->iter.bi_size == 0)
1173 aoe_end_buf(d, buf);
1174
1175 spin_unlock_irq(&d->lock);
1176 aoedev_put(d);
1177 dev_kfree_skb(skb);
1178 }
1179
1180 /* Enters with iocq.lock held.
1181 * Returns true iff responses needing processing remain.
1182 */
1183 static int
ktio(int id)1184 ktio(int id)
1185 {
1186 struct frame *f;
1187 struct list_head *pos;
1188 int i;
1189 int actual_id;
1190
1191 for (i = 0; ; ++i) {
1192 if (i == MAXIOC)
1193 return 1;
1194 if (list_empty(&iocq[id].head))
1195 return 0;
1196 pos = iocq[id].head.next;
1197 list_del(pos);
1198 f = list_entry(pos, struct frame, head);
1199 spin_unlock_irq(&iocq[id].lock);
1200 ktiocomplete(f);
1201
1202 /* Figure out if extra threads are required. */
1203 actual_id = f->t->d->aoeminor % ncpus;
1204
1205 if (!kts[actual_id].active) {
1206 BUG_ON(id != 0);
1207 mutex_lock(&ktio_spawn_lock);
1208 if (!kts[actual_id].active
1209 && aoe_ktstart(&kts[actual_id]) == 0)
1210 kts[actual_id].active = 1;
1211 mutex_unlock(&ktio_spawn_lock);
1212 }
1213 spin_lock_irq(&iocq[id].lock);
1214 }
1215 }
1216
1217 static int
kthread(void * vp)1218 kthread(void *vp)
1219 {
1220 struct ktstate *k;
1221 DECLARE_WAITQUEUE(wait, current);
1222 int more;
1223
1224 k = vp;
1225 current->flags |= PF_NOFREEZE;
1226 set_user_nice(current, -10);
1227 complete(&k->rendez); /* tell spawner we're running */
1228 do {
1229 spin_lock_irq(k->lock);
1230 more = k->fn(k->id);
1231 if (!more) {
1232 add_wait_queue(k->waitq, &wait);
1233 __set_current_state(TASK_INTERRUPTIBLE);
1234 }
1235 spin_unlock_irq(k->lock);
1236 if (!more) {
1237 schedule();
1238 remove_wait_queue(k->waitq, &wait);
1239 } else
1240 cond_resched();
1241 } while (!kthread_should_stop());
1242 complete(&k->rendez); /* tell spawner we're stopping */
1243 return 0;
1244 }
1245
1246 void
aoe_ktstop(struct ktstate * k)1247 aoe_ktstop(struct ktstate *k)
1248 {
1249 kthread_stop(k->task);
1250 wait_for_completion(&k->rendez);
1251 }
1252
1253 int
aoe_ktstart(struct ktstate * k)1254 aoe_ktstart(struct ktstate *k)
1255 {
1256 struct task_struct *task;
1257
1258 init_completion(&k->rendez);
1259 task = kthread_run(kthread, k, "%s", k->name);
1260 if (task == NULL || IS_ERR(task))
1261 return -ENOMEM;
1262 k->task = task;
1263 wait_for_completion(&k->rendez); /* allow kthread to start */
1264 init_completion(&k->rendez); /* for waiting for exit later */
1265 return 0;
1266 }
1267
1268 /* pass it off to kthreads for processing */
1269 static void
ktcomplete(struct frame * f,struct sk_buff * skb)1270 ktcomplete(struct frame *f, struct sk_buff *skb)
1271 {
1272 int id;
1273 ulong flags;
1274
1275 f->r_skb = skb;
1276 id = f->t->d->aoeminor % ncpus;
1277 spin_lock_irqsave(&iocq[id].lock, flags);
1278 if (!kts[id].active) {
1279 spin_unlock_irqrestore(&iocq[id].lock, flags);
1280 /* The thread with id has not been spawned yet,
1281 * so delegate the work to the main thread and
1282 * try spawning a new thread.
1283 */
1284 id = 0;
1285 spin_lock_irqsave(&iocq[id].lock, flags);
1286 }
1287 list_add_tail(&f->head, &iocq[id].head);
1288 spin_unlock_irqrestore(&iocq[id].lock, flags);
1289 wake_up(&ktiowq[id]);
1290 }
1291
1292 struct sk_buff *
aoecmd_ata_rsp(struct sk_buff * skb)1293 aoecmd_ata_rsp(struct sk_buff *skb)
1294 {
1295 struct aoedev *d;
1296 struct aoe_hdr *h;
1297 struct frame *f;
1298 u32 n;
1299 ulong flags;
1300 char ebuf[128];
1301 u16 aoemajor;
1302
1303 h = (struct aoe_hdr *) skb->data;
1304 aoemajor = be16_to_cpu(get_unaligned(&h->major));
1305 d = aoedev_by_aoeaddr(aoemajor, h->minor, 0);
1306 if (d == NULL) {
1307 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
1308 "for unknown device %d.%d\n",
1309 aoemajor, h->minor);
1310 aoechr_error(ebuf);
1311 return skb;
1312 }
1313
1314 spin_lock_irqsave(&d->lock, flags);
1315
1316 n = be32_to_cpu(get_unaligned(&h->tag));
1317 f = getframe(d, n);
1318 if (f) {
1319 calc_rttavg(d, f->t, tsince_hr(f));
1320 f->t->nout--;
1321 if (f->flags & FFL_PROBE)
1322 f->t->nout_probes--;
1323 } else {
1324 f = getframe_deferred(d, n);
1325 if (f) {
1326 calc_rttavg(d, NULL, tsince_hr(f));
1327 } else {
1328 calc_rttavg(d, NULL, tsince(n));
1329 spin_unlock_irqrestore(&d->lock, flags);
1330 aoedev_put(d);
1331 snprintf(ebuf, sizeof(ebuf),
1332 "%15s e%d.%d tag=%08x@%08lx s=%pm d=%pm\n",
1333 "unexpected rsp",
1334 get_unaligned_be16(&h->major),
1335 h->minor,
1336 get_unaligned_be32(&h->tag),
1337 jiffies,
1338 h->src,
1339 h->dst);
1340 aoechr_error(ebuf);
1341 return skb;
1342 }
1343 }
1344 aoecmd_work(d);
1345
1346 spin_unlock_irqrestore(&d->lock, flags);
1347
1348 ktcomplete(f, skb);
1349
1350 /*
1351 * Note here that we do not perform an aoedev_put, as we are
1352 * leaving this reference for the ktio to release.
1353 */
1354 return NULL;
1355 }
1356
1357 void
aoecmd_cfg(ushort aoemajor,unsigned char aoeminor)1358 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
1359 {
1360 struct sk_buff_head queue;
1361
1362 __skb_queue_head_init(&queue);
1363 aoecmd_cfg_pkts(aoemajor, aoeminor, &queue);
1364 aoenet_xmit(&queue);
1365 }
1366
1367 struct sk_buff *
aoecmd_ata_id(struct aoedev * d)1368 aoecmd_ata_id(struct aoedev *d)
1369 {
1370 struct aoe_hdr *h;
1371 struct aoe_atahdr *ah;
1372 struct frame *f;
1373 struct sk_buff *skb;
1374 struct aoetgt *t;
1375
1376 f = newframe(d);
1377 if (f == NULL)
1378 return NULL;
1379
1380 t = *d->tgt;
1381
1382 /* initialize the headers & frame */
1383 skb = f->skb;
1384 h = (struct aoe_hdr *) skb_mac_header(skb);
1385 ah = (struct aoe_atahdr *) (h+1);
1386 skb_put(skb, sizeof *h + sizeof *ah);
1387 memset(h, 0, skb->len);
1388 f->tag = aoehdr_atainit(d, t, h);
1389 fhash(f);
1390 t->nout++;
1391 f->waited = 0;
1392 f->waited_total = 0;
1393
1394 /* set up ata header */
1395 ah->scnt = 1;
1396 ah->cmdstat = ATA_CMD_ID_ATA;
1397 ah->lba3 = 0xa0;
1398
1399 skb->dev = t->ifp->nd;
1400
1401 d->rttavg = RTTAVG_INIT;
1402 d->rttdev = RTTDEV_INIT;
1403 d->timer.function = rexmit_timer;
1404
1405 skb = skb_clone(skb, GFP_ATOMIC);
1406 if (skb)
1407 f->sent = ktime_get();
1408
1409 return skb;
1410 }
1411
1412 static struct aoetgt **
grow_targets(struct aoedev * d)1413 grow_targets(struct aoedev *d)
1414 {
1415 ulong oldn, newn;
1416 struct aoetgt **tt;
1417
1418 oldn = d->ntargets;
1419 newn = oldn * 2;
1420 tt = kcalloc(newn, sizeof(*d->targets), GFP_ATOMIC);
1421 if (!tt)
1422 return NULL;
1423 memmove(tt, d->targets, sizeof(*d->targets) * oldn);
1424 d->tgt = tt + (d->tgt - d->targets);
1425 kfree(d->targets);
1426 d->targets = tt;
1427 d->ntargets = newn;
1428
1429 return &d->targets[oldn];
1430 }
1431
1432 static struct aoetgt *
addtgt(struct aoedev * d,char * addr,ulong nframes)1433 addtgt(struct aoedev *d, char *addr, ulong nframes)
1434 {
1435 struct aoetgt *t, **tt, **te;
1436
1437 tt = d->targets;
1438 te = tt + d->ntargets;
1439 for (; tt < te && *tt; tt++)
1440 ;
1441
1442 if (tt == te) {
1443 tt = grow_targets(d);
1444 if (!tt)
1445 goto nomem;
1446 }
1447 t = kzalloc(sizeof(*t), GFP_ATOMIC);
1448 if (!t)
1449 goto nomem;
1450 t->nframes = nframes;
1451 t->d = d;
1452 memcpy(t->addr, addr, sizeof t->addr);
1453 t->ifp = t->ifs;
1454 aoecmd_wreset(t);
1455 t->maxout = t->nframes / 2;
1456 INIT_LIST_HEAD(&t->ffree);
1457 return *tt = t;
1458
1459 nomem:
1460 pr_info("aoe: cannot allocate memory to add target\n");
1461 return NULL;
1462 }
1463
1464 static void
setdbcnt(struct aoedev * d)1465 setdbcnt(struct aoedev *d)
1466 {
1467 struct aoetgt **t, **e;
1468 int bcnt = 0;
1469
1470 t = d->targets;
1471 e = t + d->ntargets;
1472 for (; t < e && *t; t++)
1473 if (bcnt == 0 || bcnt > (*t)->minbcnt)
1474 bcnt = (*t)->minbcnt;
1475 if (bcnt != d->maxbcnt) {
1476 d->maxbcnt = bcnt;
1477 pr_info("aoe: e%ld.%d: setting %d byte data frames\n",
1478 d->aoemajor, d->aoeminor, bcnt);
1479 }
1480 }
1481
1482 static void
setifbcnt(struct aoetgt * t,struct net_device * nd,int bcnt)1483 setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt)
1484 {
1485 struct aoedev *d;
1486 struct aoeif *p, *e;
1487 int minbcnt;
1488
1489 d = t->d;
1490 minbcnt = bcnt;
1491 p = t->ifs;
1492 e = p + NAOEIFS;
1493 for (; p < e; p++) {
1494 if (p->nd == NULL)
1495 break; /* end of the valid interfaces */
1496 if (p->nd == nd) {
1497 p->bcnt = bcnt; /* we're updating */
1498 nd = NULL;
1499 } else if (minbcnt > p->bcnt)
1500 minbcnt = p->bcnt; /* find the min interface */
1501 }
1502 if (nd) {
1503 if (p == e) {
1504 pr_err("aoe: device setifbcnt failure; too many interfaces.\n");
1505 return;
1506 }
1507 dev_hold(nd);
1508 p->nd = nd;
1509 p->bcnt = bcnt;
1510 }
1511 t->minbcnt = minbcnt;
1512 setdbcnt(d);
1513 }
1514
1515 void
aoecmd_cfg_rsp(struct sk_buff * skb)1516 aoecmd_cfg_rsp(struct sk_buff *skb)
1517 {
1518 struct aoedev *d;
1519 struct aoe_hdr *h;
1520 struct aoe_cfghdr *ch;
1521 struct aoetgt *t;
1522 ulong flags, aoemajor;
1523 struct sk_buff *sl;
1524 struct sk_buff_head queue;
1525 u16 n;
1526
1527 sl = NULL;
1528 h = (struct aoe_hdr *) skb_mac_header(skb);
1529 ch = (struct aoe_cfghdr *) (h+1);
1530
1531 /*
1532 * Enough people have their dip switches set backwards to
1533 * warrant a loud message for this special case.
1534 */
1535 aoemajor = get_unaligned_be16(&h->major);
1536 if (aoemajor == 0xfff) {
1537 printk(KERN_ERR "aoe: Warning: shelf address is all ones. "
1538 "Check shelf dip switches.\n");
1539 return;
1540 }
1541 if (aoemajor == 0xffff) {
1542 pr_info("aoe: e%ld.%d: broadcast shelf number invalid\n",
1543 aoemajor, (int) h->minor);
1544 return;
1545 }
1546 if (h->minor == 0xff) {
1547 pr_info("aoe: e%ld.%d: broadcast slot number invalid\n",
1548 aoemajor, (int) h->minor);
1549 return;
1550 }
1551
1552 n = be16_to_cpu(ch->bufcnt);
1553 if (n > aoe_maxout) /* keep it reasonable */
1554 n = aoe_maxout;
1555
1556 d = aoedev_by_aoeaddr(aoemajor, h->minor, 1);
1557 if (d == NULL) {
1558 pr_info("aoe: device allocation failure\n");
1559 return;
1560 }
1561
1562 spin_lock_irqsave(&d->lock, flags);
1563
1564 t = gettgt(d, h->src);
1565 if (t) {
1566 t->nframes = n;
1567 if (n < t->maxout)
1568 aoecmd_wreset(t);
1569 } else {
1570 t = addtgt(d, h->src, n);
1571 if (!t)
1572 goto bail;
1573 }
1574 n = skb->dev->mtu;
1575 n -= sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr);
1576 n /= 512;
1577 if (n > ch->scnt)
1578 n = ch->scnt;
1579 n = n ? n * 512 : DEFAULTBCNT;
1580 setifbcnt(t, skb->dev, n);
1581
1582 /* don't change users' perspective */
1583 if (d->nopen == 0) {
1584 d->fw_ver = be16_to_cpu(ch->fwver);
1585 sl = aoecmd_ata_id(d);
1586 }
1587 bail:
1588 spin_unlock_irqrestore(&d->lock, flags);
1589 aoedev_put(d);
1590 if (sl) {
1591 __skb_queue_head_init(&queue);
1592 __skb_queue_tail(&queue, sl);
1593 aoenet_xmit(&queue);
1594 }
1595 }
1596
1597 void
aoecmd_wreset(struct aoetgt * t)1598 aoecmd_wreset(struct aoetgt *t)
1599 {
1600 t->maxout = 1;
1601 t->ssthresh = t->nframes / 2;
1602 t->next_cwnd = t->nframes;
1603 }
1604
1605 void
aoecmd_cleanslate(struct aoedev * d)1606 aoecmd_cleanslate(struct aoedev *d)
1607 {
1608 struct aoetgt **t, **te;
1609
1610 d->rttavg = RTTAVG_INIT;
1611 d->rttdev = RTTDEV_INIT;
1612 d->maxbcnt = 0;
1613
1614 t = d->targets;
1615 te = t + d->ntargets;
1616 for (; t < te && *t; t++)
1617 aoecmd_wreset(*t);
1618 }
1619
1620 void
aoe_failbuf(struct aoedev * d,struct buf * buf)1621 aoe_failbuf(struct aoedev *d, struct buf *buf)
1622 {
1623 if (buf == NULL)
1624 return;
1625 buf->iter.bi_size = 0;
1626 buf->bio->bi_status = BLK_STS_IOERR;
1627 if (buf->nframesout == 0)
1628 aoe_end_buf(d, buf);
1629 }
1630
1631 void
aoe_flush_iocq(void)1632 aoe_flush_iocq(void)
1633 {
1634 int i;
1635
1636 for (i = 0; i < ncpus; i++) {
1637 if (kts[i].active)
1638 aoe_flush_iocq_by_index(i);
1639 }
1640 }
1641
1642 void
aoe_flush_iocq_by_index(int id)1643 aoe_flush_iocq_by_index(int id)
1644 {
1645 struct frame *f;
1646 struct aoedev *d;
1647 LIST_HEAD(flist);
1648 struct list_head *pos;
1649 struct sk_buff *skb;
1650 ulong flags;
1651
1652 spin_lock_irqsave(&iocq[id].lock, flags);
1653 list_splice_init(&iocq[id].head, &flist);
1654 spin_unlock_irqrestore(&iocq[id].lock, flags);
1655 while (!list_empty(&flist)) {
1656 pos = flist.next;
1657 list_del(pos);
1658 f = list_entry(pos, struct frame, head);
1659 d = f->t->d;
1660 skb = f->r_skb;
1661 spin_lock_irqsave(&d->lock, flags);
1662 if (f->buf) {
1663 f->buf->nframesout--;
1664 aoe_failbuf(d, f->buf);
1665 }
1666 aoe_freetframe(f);
1667 spin_unlock_irqrestore(&d->lock, flags);
1668 dev_kfree_skb(skb);
1669 aoedev_put(d);
1670 }
1671 }
1672
1673 int __init
aoecmd_init(void)1674 aoecmd_init(void)
1675 {
1676 void *p;
1677 int i;
1678 int ret;
1679
1680 /* get_zeroed_page returns page with ref count 1 */
1681 p = (void *) get_zeroed_page(GFP_KERNEL);
1682 if (!p)
1683 return -ENOMEM;
1684 empty_page = virt_to_page(p);
1685
1686 ncpus = num_online_cpus();
1687
1688 iocq = kcalloc(ncpus, sizeof(struct iocq_ktio), GFP_KERNEL);
1689 if (!iocq)
1690 return -ENOMEM;
1691
1692 kts = kcalloc(ncpus, sizeof(struct ktstate), GFP_KERNEL);
1693 if (!kts) {
1694 ret = -ENOMEM;
1695 goto kts_fail;
1696 }
1697
1698 ktiowq = kcalloc(ncpus, sizeof(wait_queue_head_t), GFP_KERNEL);
1699 if (!ktiowq) {
1700 ret = -ENOMEM;
1701 goto ktiowq_fail;
1702 }
1703
1704 for (i = 0; i < ncpus; i++) {
1705 INIT_LIST_HEAD(&iocq[i].head);
1706 spin_lock_init(&iocq[i].lock);
1707 init_waitqueue_head(&ktiowq[i]);
1708 snprintf(kts[i].name, sizeof(kts[i].name), "aoe_ktio%d", i);
1709 kts[i].fn = ktio;
1710 kts[i].waitq = &ktiowq[i];
1711 kts[i].lock = &iocq[i].lock;
1712 kts[i].id = i;
1713 kts[i].active = 0;
1714 }
1715 kts[0].active = 1;
1716 if (aoe_ktstart(&kts[0])) {
1717 ret = -ENOMEM;
1718 goto ktstart_fail;
1719 }
1720 return 0;
1721
1722 ktstart_fail:
1723 kfree(ktiowq);
1724 ktiowq_fail:
1725 kfree(kts);
1726 kts_fail:
1727 kfree(iocq);
1728
1729 return ret;
1730 }
1731
1732 void
aoecmd_exit(void)1733 aoecmd_exit(void)
1734 {
1735 int i;
1736
1737 for (i = 0; i < ncpus; i++)
1738 if (kts[i].active)
1739 aoe_ktstop(&kts[i]);
1740
1741 aoe_flush_iocq();
1742
1743 /* Free up the iocq and thread speicific configuration
1744 * allocated during startup.
1745 */
1746 kfree(iocq);
1747 kfree(kts);
1748 kfree(ktiowq);
1749
1750 free_page((unsigned long) page_address(empty_page));
1751 empty_page = NULL;
1752 }
1753