drivers/block/aoe/aoecmd.c

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This source file includes following definitions.
new_skb
getframe_deferred
getframe
newtag
aoehdr_atainit
put_lba
ifrotate
skb_pool_put
skb_pool_get
aoe_freetframe
newtframe
newframe
skb_fillup
fhash
ata_rw_frameinit
aoecmd_ata_rw
aoecmd_cfg_pkts
resend
tsince_hr
tsince
getif
ejectif
reassign_frame
probe
rto
rexmit_deferred
scorn
count_targets
rexmit_timer
bufinit
nextbuf
aoecmd_work
aoecmd_sleepwork
ata_ident_fixstring
ataid_complete
calc_rttavg
gettgt
bvcpy
aoe_end_request
aoe_end_buf
ktiocomplete
ktio
kthread
aoe_ktstop
aoe_ktstart
ktcomplete
aoecmd_ata_rsp
aoecmd_cfg
aoecmd_ata_id
grow_targets
addtgt
setdbcnt
setifbcnt
aoecmd_cfg_rsp
aoecmd_wreset
aoecmd_cleanslate
aoe_failbuf
aoe_flush_iocq
aoe_flush_iocq_by_index
aoecmd_init
aoecmd_exit
   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 *
  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 *
  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 *
  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
 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
 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
 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 *
 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
 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 *
 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
 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 *
 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 *
 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
 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
 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
 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
 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
 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
 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
 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
 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 *
 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
 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 *
 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
 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
 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
 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
 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
 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
 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
 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 *
 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
 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
 890 aoecmd_sleepwork(struct work_struct *work)
 891 {
 892         struct aoedev *d = container_of(work, struct aoedev, work);
 893         struct block_device *bd;
 894         u64 ssize;
 895 
 896         if (d->flags & DEVFL_GDALLOC)
 897                 aoeblk_gdalloc(d);
 898 
 899         if (d->flags & DEVFL_NEWSIZE) {
 900                 ssize = get_capacity(d->gd);
 901                 bd = bdget_disk(d->gd, 0);
 902                 if (bd) {
 903                         inode_lock(bd->bd_inode);
 904                         i_size_write(bd->bd_inode, (loff_t)ssize<<9);
 905                         inode_unlock(bd->bd_inode);
 906                         bdput(bd);
 907                 }
 908                 spin_lock_irq(&d->lock);
 909                 d->flags |= DEVFL_UP;
 910                 d->flags &= ~DEVFL_NEWSIZE;
 911                 spin_unlock_irq(&d->lock);
 912         }
 913 }
 914 
 915 static void
 916 ata_ident_fixstring(u16 *id, int ns)
 917 {
 918         u16 s;
 919 
 920         while (ns-- > 0) {
 921                 s = *id;
 922                 *id++ = s >> 8 | s << 8;
 923         }
 924 }
 925 
 926 static void
 927 ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
 928 {
 929         u64 ssize;
 930         u16 n;
 931 
 932         /* word 83: command set supported */
 933         n = get_unaligned_le16(&id[83 << 1]);
 934 
 935         /* word 86: command set/feature enabled */
 936         n |= get_unaligned_le16(&id[86 << 1]);
 937 
 938         if (n & (1<<10)) {      /* bit 10: LBA 48 */
 939                 d->flags |= DEVFL_EXT;
 940 
 941                 /* word 100: number lba48 sectors */
 942                 ssize = get_unaligned_le64(&id[100 << 1]);
 943 
 944                 /* set as in ide-disk.c:init_idedisk_capacity */
 945                 d->geo.cylinders = ssize;
 946                 d->geo.cylinders /= (255 * 63);
 947                 d->geo.heads = 255;
 948                 d->geo.sectors = 63;
 949         } else {
 950                 d->flags &= ~DEVFL_EXT;
 951 
 952                 /* number lba28 sectors */
 953                 ssize = get_unaligned_le32(&id[60 << 1]);
 954 
 955                 /* NOTE: obsolete in ATA 6 */
 956                 d->geo.cylinders = get_unaligned_le16(&id[54 << 1]);
 957                 d->geo.heads = get_unaligned_le16(&id[55 << 1]);
 958                 d->geo.sectors = get_unaligned_le16(&id[56 << 1]);
 959         }
 960 
 961         ata_ident_fixstring((u16 *) &id[10<<1], 10);    /* serial */
 962         ata_ident_fixstring((u16 *) &id[23<<1], 4);     /* firmware */
 963         ata_ident_fixstring((u16 *) &id[27<<1], 20);    /* model */
 964         memcpy(d->ident, id, sizeof(d->ident));
 965 
 966         if (d->ssize != ssize)
 967                 printk(KERN_INFO
 968                         "aoe: %pm e%ld.%d v%04x has %llu sectors\n",
 969                         t->addr,
 970                         d->aoemajor, d->aoeminor,
 971                         d->fw_ver, (long long)ssize);
 972         d->ssize = ssize;
 973         d->geo.start = 0;
 974         if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
 975                 return;
 976         if (d->gd != NULL) {
 977                 set_capacity(d->gd, ssize);
 978                 d->flags |= DEVFL_NEWSIZE;
 979         } else
 980                 d->flags |= DEVFL_GDALLOC;
 981         schedule_work(&d->work);
 982 }
 983 
 984 static void
 985 calc_rttavg(struct aoedev *d, struct aoetgt *t, int rtt)
 986 {
 987         register long n;
 988 
 989         n = rtt;
 990 
 991         /* cf. Congestion Avoidance and Control, Jacobson & Karels, 1988 */
 992         n -= d->rttavg >> RTTSCALE;
 993         d->rttavg += n;
 994         if (n < 0)
 995                 n = -n;
 996         n -= d->rttdev >> RTTDSCALE;
 997         d->rttdev += n;
 998 
 999         if (!t || t->maxout >= t->nframes)
1000                 return;
1001         if (t->maxout < t->ssthresh)
1002                 t->maxout += 1;
1003         else if (t->nout == t->maxout && t->next_cwnd-- == 0) {
1004                 t->maxout += 1;
1005                 t->next_cwnd = t->maxout;
1006         }
1007 }
1008 
1009 static struct aoetgt *
1010 gettgt(struct aoedev *d, char *addr)
1011 {
1012         struct aoetgt **t, **e;
1013 
1014         t = d->targets;
1015         e = t + d->ntargets;
1016         for (; t < e && *t; t++)
1017                 if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0)
1018                         return *t;
1019         return NULL;
1020 }
1021 
1022 static void
1023 bvcpy(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter, long cnt)
1024 {
1025         int soff = 0;
1026         struct bio_vec bv;
1027 
1028         iter.bi_size = cnt;
1029 
1030         __bio_for_each_segment(bv, bio, iter, iter) {
1031                 char *p = kmap_atomic(bv.bv_page) + bv.bv_offset;
1032                 skb_copy_bits(skb, soff, p, bv.bv_len);
1033                 kunmap_atomic(p);
1034                 soff += bv.bv_len;
1035         }
1036 }
1037 
1038 void
1039 aoe_end_request(struct aoedev *d, struct request *rq, int fastfail)
1040 {
1041         struct bio *bio;
1042         int bok;
1043         struct request_queue *q;
1044         blk_status_t err = BLK_STS_OK;
1045 
1046         q = d->blkq;
1047         if (rq == d->ip.rq)
1048                 d->ip.rq = NULL;
1049         do {
1050                 bio = rq->bio;
1051                 bok = !fastfail && !bio->bi_status;
1052                 if (!bok)
1053                         err = BLK_STS_IOERR;
1054         } while (blk_update_request(rq, bok ? BLK_STS_OK : BLK_STS_IOERR, bio->bi_iter.bi_size));
1055 
1056         __blk_mq_end_request(rq, err);
1057 
1058         /* cf. http://lkml.org/lkml/2006/10/31/28 */
1059         if (!fastfail)
1060                 blk_mq_run_hw_queues(q, true);
1061 }
1062 
1063 static void
1064 aoe_end_buf(struct aoedev *d, struct buf *buf)
1065 {
1066         struct request *rq = buf->rq;
1067         struct aoe_req *req = blk_mq_rq_to_pdu(rq);
1068 
1069         if (buf == d->ip.buf)
1070                 d->ip.buf = NULL;
1071         mempool_free(buf, d->bufpool);
1072         if (--req->nr_bios == 0)
1073                 aoe_end_request(d, rq, 0);
1074 }
1075 
1076 static void
1077 ktiocomplete(struct frame *f)
1078 {
1079         struct aoe_hdr *hin, *hout;
1080         struct aoe_atahdr *ahin, *ahout;
1081         struct buf *buf;
1082         struct sk_buff *skb;
1083         struct aoetgt *t;
1084         struct aoeif *ifp;
1085         struct aoedev *d;
1086         long n;
1087         int untainted;
1088 
1089         if (f == NULL)
1090                 return;
1091 
1092         t = f->t;
1093         d = t->d;
1094         skb = f->r_skb;
1095         buf = f->buf;
1096         if (f->flags & FFL_PROBE)
1097                 goto out;
1098         if (!skb)               /* just fail the buf. */
1099                 goto noskb;
1100 
1101         hout = (struct aoe_hdr *) skb_mac_header(f->skb);
1102         ahout = (struct aoe_atahdr *) (hout+1);
1103 
1104         hin = (struct aoe_hdr *) skb->data;
1105         skb_pull(skb, sizeof(*hin));
1106         ahin = (struct aoe_atahdr *) skb->data;
1107         skb_pull(skb, sizeof(*ahin));
1108         if (ahin->cmdstat & 0xa9) {     /* these bits cleared on success */
1109                 pr_err("aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n",
1110                         ahout->cmdstat, ahin->cmdstat,
1111                         d->aoemajor, d->aoeminor);
1112 noskb:          if (buf)
1113                         buf->bio->bi_status = BLK_STS_IOERR;
1114                 goto out;
1115         }
1116 
1117         n = ahout->scnt << 9;
1118         switch (ahout->cmdstat) {
1119         case ATA_CMD_PIO_READ:
1120         case ATA_CMD_PIO_READ_EXT:
1121                 if (skb->len < n) {
1122                         pr_err("%s e%ld.%d.  skb->len=%d need=%ld\n",
1123                                 "aoe: runt data size in read from",
1124                                 (long) d->aoemajor, d->aoeminor,
1125                                skb->len, n);
1126                         buf->bio->bi_status = BLK_STS_IOERR;
1127                         break;
1128                 }
1129                 if (n > f->iter.bi_size) {
1130                         pr_err_ratelimited("%s e%ld.%d.  bytes=%ld need=%u\n",
1131                                 "aoe: too-large data size in read from",
1132                                 (long) d->aoemajor, d->aoeminor,
1133                                 n, f->iter.bi_size);
1134                         buf->bio->bi_status = BLK_STS_IOERR;
1135                         break;
1136                 }
1137                 bvcpy(skb, f->buf->bio, f->iter, n);
1138                 /* fall through */
1139         case ATA_CMD_PIO_WRITE:
1140         case ATA_CMD_PIO_WRITE_EXT:
1141                 spin_lock_irq(&d->lock);
1142                 ifp = getif(t, skb->dev);
1143                 if (ifp)
1144                         ifp->lost = 0;
1145                 spin_unlock_irq(&d->lock);
1146                 break;
1147         case ATA_CMD_ID_ATA:
1148                 if (skb->len < 512) {
1149                         pr_info("%s e%ld.%d.  skb->len=%d need=512\n",
1150                                 "aoe: runt data size in ataid from",
1151                                 (long) d->aoemajor, d->aoeminor,
1152                                 skb->len);
1153                         break;
1154                 }
1155                 if (skb_linearize(skb))
1156                         break;
1157                 spin_lock_irq(&d->lock);
1158                 ataid_complete(d, t, skb->data);
1159                 spin_unlock_irq(&d->lock);
1160                 break;
1161         default:
1162                 pr_info("aoe: unrecognized ata command %2.2Xh for %d.%d\n",
1163                         ahout->cmdstat,
1164                         be16_to_cpu(get_unaligned(&hin->major)),
1165                         hin->minor);
1166         }
1167 out:
1168         spin_lock_irq(&d->lock);
1169         if (t->taint > 0
1170         && --t->taint > 0
1171         && t->nout_probes == 0) {
1172                 count_targets(d, &untainted);
1173                 if (untainted > 0) {
1174                         probe(t);
1175                         t->nout_probes++;
1176                 }
1177         }
1178 
1179         aoe_freetframe(f);
1180 
1181         if (buf && --buf->nframesout == 0 && buf->iter.bi_size == 0)
1182                 aoe_end_buf(d, buf);
1183 
1184         spin_unlock_irq(&d->lock);
1185         aoedev_put(d);
1186         dev_kfree_skb(skb);
1187 }
1188 
1189 /* Enters with iocq.lock held.
1190  * Returns true iff responses needing processing remain.
1191  */
1192 static int
1193 ktio(int id)
1194 {
1195         struct frame *f;
1196         struct list_head *pos;
1197         int i;
1198         int actual_id;
1199 
1200         for (i = 0; ; ++i) {
1201                 if (i == MAXIOC)
1202                         return 1;
1203                 if (list_empty(&iocq[id].head))
1204                         return 0;
1205                 pos = iocq[id].head.next;
1206                 list_del(pos);
1207                 f = list_entry(pos, struct frame, head);
1208                 spin_unlock_irq(&iocq[id].lock);
1209                 ktiocomplete(f);
1210 
1211                 /* Figure out if extra threads are required. */
1212                 actual_id = f->t->d->aoeminor % ncpus;
1213 
1214                 if (!kts[actual_id].active) {
1215                         BUG_ON(id != 0);
1216                         mutex_lock(&ktio_spawn_lock);
1217                         if (!kts[actual_id].active
1218                                 && aoe_ktstart(&kts[actual_id]) == 0)
1219                                 kts[actual_id].active = 1;
1220                         mutex_unlock(&ktio_spawn_lock);
1221                 }
1222                 spin_lock_irq(&iocq[id].lock);
1223         }
1224 }
1225 
1226 static int
1227 kthread(void *vp)
1228 {
1229         struct ktstate *k;
1230         DECLARE_WAITQUEUE(wait, current);
1231         int more;
1232 
1233         k = vp;
1234         current->flags |= PF_NOFREEZE;
1235         set_user_nice(current, -10);
1236         complete(&k->rendez);   /* tell spawner we're running */
1237         do {
1238                 spin_lock_irq(k->lock);
1239                 more = k->fn(k->id);
1240                 if (!more) {
1241                         add_wait_queue(k->waitq, &wait);
1242                         __set_current_state(TASK_INTERRUPTIBLE);
1243                 }
1244                 spin_unlock_irq(k->lock);
1245                 if (!more) {
1246                         schedule();
1247                         remove_wait_queue(k->waitq, &wait);
1248                 } else
1249                         cond_resched();
1250         } while (!kthread_should_stop());
1251         complete(&k->rendez);   /* tell spawner we're stopping */
1252         return 0;
1253 }
1254 
1255 void
1256 aoe_ktstop(struct ktstate *k)
1257 {
1258         kthread_stop(k->task);
1259         wait_for_completion(&k->rendez);
1260 }
1261 
1262 int
1263 aoe_ktstart(struct ktstate *k)
1264 {
1265         struct task_struct *task;
1266 
1267         init_completion(&k->rendez);
1268         task = kthread_run(kthread, k, "%s", k->name);
1269         if (task == NULL || IS_ERR(task))
1270                 return -ENOMEM;
1271         k->task = task;
1272         wait_for_completion(&k->rendez); /* allow kthread to start */
1273         init_completion(&k->rendez);    /* for waiting for exit later */
1274         return 0;
1275 }
1276 
1277 /* pass it off to kthreads for processing */
1278 static void
1279 ktcomplete(struct frame *f, struct sk_buff *skb)
1280 {
1281         int id;
1282         ulong flags;
1283 
1284         f->r_skb = skb;
1285         id = f->t->d->aoeminor % ncpus;
1286         spin_lock_irqsave(&iocq[id].lock, flags);
1287         if (!kts[id].active) {
1288                 spin_unlock_irqrestore(&iocq[id].lock, flags);
1289                 /* The thread with id has not been spawned yet,
1290                  * so delegate the work to the main thread and
1291                  * try spawning a new thread.
1292                  */
1293                 id = 0;
1294                 spin_lock_irqsave(&iocq[id].lock, flags);
1295         }
1296         list_add_tail(&f->head, &iocq[id].head);
1297         spin_unlock_irqrestore(&iocq[id].lock, flags);
1298         wake_up(&ktiowq[id]);
1299 }
1300 
1301 struct sk_buff *
1302 aoecmd_ata_rsp(struct sk_buff *skb)
1303 {
1304         struct aoedev *d;
1305         struct aoe_hdr *h;
1306         struct frame *f;
1307         u32 n;
1308         ulong flags;
1309         char ebuf[128];
1310         u16 aoemajor;
1311 
1312         h = (struct aoe_hdr *) skb->data;
1313         aoemajor = be16_to_cpu(get_unaligned(&h->major));
1314         d = aoedev_by_aoeaddr(aoemajor, h->minor, 0);
1315         if (d == NULL) {
1316                 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
1317                         "for unknown device %d.%d\n",
1318                         aoemajor, h->minor);
1319                 aoechr_error(ebuf);
1320                 return skb;
1321         }
1322 
1323         spin_lock_irqsave(&d->lock, flags);
1324 
1325         n = be32_to_cpu(get_unaligned(&h->tag));
1326         f = getframe(d, n);
1327         if (f) {
1328                 calc_rttavg(d, f->t, tsince_hr(f));
1329                 f->t->nout--;
1330                 if (f->flags & FFL_PROBE)
1331                         f->t->nout_probes--;
1332         } else {
1333                 f = getframe_deferred(d, n);
1334                 if (f) {
1335                         calc_rttavg(d, NULL, tsince_hr(f));
1336                 } else {
1337                         calc_rttavg(d, NULL, tsince(n));
1338                         spin_unlock_irqrestore(&d->lock, flags);
1339                         aoedev_put(d);
1340                         snprintf(ebuf, sizeof(ebuf),
1341                                  "%15s e%d.%d    tag=%08x@%08lx s=%pm d=%pm\n",
1342                                  "unexpected rsp",
1343                                  get_unaligned_be16(&h->major),
1344                                  h->minor,
1345                                  get_unaligned_be32(&h->tag),
1346                                  jiffies,
1347                                  h->src,
1348                                  h->dst);
1349                         aoechr_error(ebuf);
1350                         return skb;
1351                 }
1352         }
1353         aoecmd_work(d);
1354 
1355         spin_unlock_irqrestore(&d->lock, flags);
1356 
1357         ktcomplete(f, skb);
1358 
1359         /*
1360          * Note here that we do not perform an aoedev_put, as we are
1361          * leaving this reference for the ktio to release.
1362          */
1363         return NULL;
1364 }
1365 
1366 void
1367 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
1368 {
1369         struct sk_buff_head queue;
1370 
1371         __skb_queue_head_init(&queue);
1372         aoecmd_cfg_pkts(aoemajor, aoeminor, &queue);
1373         aoenet_xmit(&queue);
1374 }
1375 
1376 struct sk_buff *
1377 aoecmd_ata_id(struct aoedev *d)
1378 {
1379         struct aoe_hdr *h;
1380         struct aoe_atahdr *ah;
1381         struct frame *f;
1382         struct sk_buff *skb;
1383         struct aoetgt *t;
1384 
1385         f = newframe(d);
1386         if (f == NULL)
1387                 return NULL;
1388 
1389         t = *d->tgt;
1390 
1391         /* initialize the headers & frame */
1392         skb = f->skb;
1393         h = (struct aoe_hdr *) skb_mac_header(skb);
1394         ah = (struct aoe_atahdr *) (h+1);
1395         skb_put(skb, sizeof *h + sizeof *ah);
1396         memset(h, 0, skb->len);
1397         f->tag = aoehdr_atainit(d, t, h);
1398         fhash(f);
1399         t->nout++;
1400         f->waited = 0;
1401         f->waited_total = 0;
1402 
1403         /* set up ata header */
1404         ah->scnt = 1;
1405         ah->cmdstat = ATA_CMD_ID_ATA;
1406         ah->lba3 = 0xa0;
1407 
1408         skb->dev = t->ifp->nd;
1409 
1410         d->rttavg = RTTAVG_INIT;
1411         d->rttdev = RTTDEV_INIT;
1412         d->timer.function = rexmit_timer;
1413 
1414         skb = skb_clone(skb, GFP_ATOMIC);
1415         if (skb)
1416                 f->sent = ktime_get();
1417 
1418         return skb;
1419 }
1420 
1421 static struct aoetgt **
1422 grow_targets(struct aoedev *d)
1423 {
1424         ulong oldn, newn;
1425         struct aoetgt **tt;
1426 
1427         oldn = d->ntargets;
1428         newn = oldn * 2;
1429         tt = kcalloc(newn, sizeof(*d->targets), GFP_ATOMIC);
1430         if (!tt)
1431                 return NULL;
1432         memmove(tt, d->targets, sizeof(*d->targets) * oldn);
1433         d->tgt = tt + (d->tgt - d->targets);
1434         kfree(d->targets);
1435         d->targets = tt;
1436         d->ntargets = newn;
1437 
1438         return &d->targets[oldn];
1439 }
1440 
1441 static struct aoetgt *
1442 addtgt(struct aoedev *d, char *addr, ulong nframes)
1443 {
1444         struct aoetgt *t, **tt, **te;
1445 
1446         tt = d->targets;
1447         te = tt + d->ntargets;
1448         for (; tt < te && *tt; tt++)
1449                 ;
1450 
1451         if (tt == te) {
1452                 tt = grow_targets(d);
1453                 if (!tt)
1454                         goto nomem;
1455         }
1456         t = kzalloc(sizeof(*t), GFP_ATOMIC);
1457         if (!t)
1458                 goto nomem;
1459         t->nframes = nframes;
1460         t->d = d;
1461         memcpy(t->addr, addr, sizeof t->addr);
1462         t->ifp = t->ifs;
1463         aoecmd_wreset(t);
1464         t->maxout = t->nframes / 2;
1465         INIT_LIST_HEAD(&t->ffree);
1466         return *tt = t;
1467 
1468  nomem:
1469         pr_info("aoe: cannot allocate memory to add target\n");
1470         return NULL;
1471 }
1472 
1473 static void
1474 setdbcnt(struct aoedev *d)
1475 {
1476         struct aoetgt **t, **e;
1477         int bcnt = 0;
1478 
1479         t = d->targets;
1480         e = t + d->ntargets;
1481         for (; t < e && *t; t++)
1482                 if (bcnt == 0 || bcnt > (*t)->minbcnt)
1483                         bcnt = (*t)->minbcnt;
1484         if (bcnt != d->maxbcnt) {
1485                 d->maxbcnt = bcnt;
1486                 pr_info("aoe: e%ld.%d: setting %d byte data frames\n",
1487                         d->aoemajor, d->aoeminor, bcnt);
1488         }
1489 }
1490 
1491 static void
1492 setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt)
1493 {
1494         struct aoedev *d;
1495         struct aoeif *p, *e;
1496         int minbcnt;
1497 
1498         d = t->d;
1499         minbcnt = bcnt;
1500         p = t->ifs;
1501         e = p + NAOEIFS;
1502         for (; p < e; p++) {
1503                 if (p->nd == NULL)
1504                         break;          /* end of the valid interfaces */
1505                 if (p->nd == nd) {
1506                         p->bcnt = bcnt; /* we're updating */
1507                         nd = NULL;
1508                 } else if (minbcnt > p->bcnt)
1509                         minbcnt = p->bcnt; /* find the min interface */
1510         }
1511         if (nd) {
1512                 if (p == e) {
1513                         pr_err("aoe: device setifbcnt failure; too many interfaces.\n");
1514                         return;
1515                 }
1516                 dev_hold(nd);
1517                 p->nd = nd;
1518                 p->bcnt = bcnt;
1519         }
1520         t->minbcnt = minbcnt;
1521         setdbcnt(d);
1522 }
1523 
1524 void
1525 aoecmd_cfg_rsp(struct sk_buff *skb)
1526 {
1527         struct aoedev *d;
1528         struct aoe_hdr *h;
1529         struct aoe_cfghdr *ch;
1530         struct aoetgt *t;
1531         ulong flags, aoemajor;
1532         struct sk_buff *sl;
1533         struct sk_buff_head queue;
1534         u16 n;
1535 
1536         sl = NULL;
1537         h = (struct aoe_hdr *) skb_mac_header(skb);
1538         ch = (struct aoe_cfghdr *) (h+1);
1539 
1540         /*
1541          * Enough people have their dip switches set backwards to
1542          * warrant a loud message for this special case.
1543          */
1544         aoemajor = get_unaligned_be16(&h->major);
1545         if (aoemajor == 0xfff) {
1546                 printk(KERN_ERR "aoe: Warning: shelf address is all ones.  "
1547                         "Check shelf dip switches.\n");
1548                 return;
1549         }
1550         if (aoemajor == 0xffff) {
1551                 pr_info("aoe: e%ld.%d: broadcast shelf number invalid\n",
1552                         aoemajor, (int) h->minor);
1553                 return;
1554         }
1555         if (h->minor == 0xff) {
1556                 pr_info("aoe: e%ld.%d: broadcast slot number invalid\n",
1557                         aoemajor, (int) h->minor);
1558                 return;
1559         }
1560 
1561         n = be16_to_cpu(ch->bufcnt);
1562         if (n > aoe_maxout)     /* keep it reasonable */
1563                 n = aoe_maxout;
1564 
1565         d = aoedev_by_aoeaddr(aoemajor, h->minor, 1);
1566         if (d == NULL) {
1567                 pr_info("aoe: device allocation failure\n");
1568                 return;
1569         }
1570 
1571         spin_lock_irqsave(&d->lock, flags);
1572 
1573         t = gettgt(d, h->src);
1574         if (t) {
1575                 t->nframes = n;
1576                 if (n < t->maxout)
1577                         aoecmd_wreset(t);
1578         } else {
1579                 t = addtgt(d, h->src, n);
1580                 if (!t)
1581                         goto bail;
1582         }
1583         n = skb->dev->mtu;
1584         n -= sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr);
1585         n /= 512;
1586         if (n > ch->scnt)
1587                 n = ch->scnt;
1588         n = n ? n * 512 : DEFAULTBCNT;
1589         setifbcnt(t, skb->dev, n);
1590 
1591         /* don't change users' perspective */
1592         if (d->nopen == 0) {
1593                 d->fw_ver = be16_to_cpu(ch->fwver);
1594                 sl = aoecmd_ata_id(d);
1595         }
1596 bail:
1597         spin_unlock_irqrestore(&d->lock, flags);
1598         aoedev_put(d);
1599         if (sl) {
1600                 __skb_queue_head_init(&queue);
1601                 __skb_queue_tail(&queue, sl);
1602                 aoenet_xmit(&queue);
1603         }
1604 }
1605 
1606 void
1607 aoecmd_wreset(struct aoetgt *t)
1608 {
1609         t->maxout = 1;
1610         t->ssthresh = t->nframes / 2;
1611         t->next_cwnd = t->nframes;
1612 }
1613 
1614 void
1615 aoecmd_cleanslate(struct aoedev *d)
1616 {
1617         struct aoetgt **t, **te;
1618 
1619         d->rttavg = RTTAVG_INIT;
1620         d->rttdev = RTTDEV_INIT;
1621         d->maxbcnt = 0;
1622 
1623         t = d->targets;
1624         te = t + d->ntargets;
1625         for (; t < te && *t; t++)
1626                 aoecmd_wreset(*t);
1627 }
1628 
1629 void
1630 aoe_failbuf(struct aoedev *d, struct buf *buf)
1631 {
1632         if (buf == NULL)
1633                 return;
1634         buf->iter.bi_size = 0;
1635         buf->bio->bi_status = BLK_STS_IOERR;
1636         if (buf->nframesout == 0)
1637                 aoe_end_buf(d, buf);
1638 }
1639 
1640 void
1641 aoe_flush_iocq(void)
1642 {
1643         int i;
1644 
1645         for (i = 0; i < ncpus; i++) {
1646                 if (kts[i].active)
1647                         aoe_flush_iocq_by_index(i);
1648         }
1649 }
1650 
1651 void
1652 aoe_flush_iocq_by_index(int id)
1653 {
1654         struct frame *f;
1655         struct aoedev *d;
1656         LIST_HEAD(flist);
1657         struct list_head *pos;
1658         struct sk_buff *skb;
1659         ulong flags;
1660 
1661         spin_lock_irqsave(&iocq[id].lock, flags);
1662         list_splice_init(&iocq[id].head, &flist);
1663         spin_unlock_irqrestore(&iocq[id].lock, flags);
1664         while (!list_empty(&flist)) {
1665                 pos = flist.next;
1666                 list_del(pos);
1667                 f = list_entry(pos, struct frame, head);
1668                 d = f->t->d;
1669                 skb = f->r_skb;
1670                 spin_lock_irqsave(&d->lock, flags);
1671                 if (f->buf) {
1672                         f->buf->nframesout--;
1673                         aoe_failbuf(d, f->buf);
1674                 }
1675                 aoe_freetframe(f);
1676                 spin_unlock_irqrestore(&d->lock, flags);
1677                 dev_kfree_skb(skb);
1678                 aoedev_put(d);
1679         }
1680 }
1681 
1682 int __init
1683 aoecmd_init(void)
1684 {
1685         void *p;
1686         int i;
1687         int ret;
1688 
1689         /* get_zeroed_page returns page with ref count 1 */
1690         p = (void *) get_zeroed_page(GFP_KERNEL);
1691         if (!p)
1692                 return -ENOMEM;
1693         empty_page = virt_to_page(p);
1694 
1695         ncpus = num_online_cpus();
1696 
1697         iocq = kcalloc(ncpus, sizeof(struct iocq_ktio), GFP_KERNEL);
1698         if (!iocq)
1699                 return -ENOMEM;
1700 
1701         kts = kcalloc(ncpus, sizeof(struct ktstate), GFP_KERNEL);
1702         if (!kts) {
1703                 ret = -ENOMEM;
1704                 goto kts_fail;
1705         }
1706 
1707         ktiowq = kcalloc(ncpus, sizeof(wait_queue_head_t), GFP_KERNEL);
1708         if (!ktiowq) {
1709                 ret = -ENOMEM;
1710                 goto ktiowq_fail;
1711         }
1712 
1713         mutex_init(&ktio_spawn_lock);
1714 
1715         for (i = 0; i < ncpus; i++) {
1716                 INIT_LIST_HEAD(&iocq[i].head);
1717                 spin_lock_init(&iocq[i].lock);
1718                 init_waitqueue_head(&ktiowq[i]);
1719                 snprintf(kts[i].name, sizeof(kts[i].name), "aoe_ktio%d", i);
1720                 kts[i].fn = ktio;
1721                 kts[i].waitq = &ktiowq[i];
1722                 kts[i].lock = &iocq[i].lock;
1723                 kts[i].id = i;
1724                 kts[i].active = 0;
1725         }
1726         kts[0].active = 1;
1727         if (aoe_ktstart(&kts[0])) {
1728                 ret = -ENOMEM;
1729                 goto ktstart_fail;
1730         }
1731         return 0;
1732 
1733 ktstart_fail:
1734         kfree(ktiowq);
1735 ktiowq_fail:
1736         kfree(kts);
1737 kts_fail:
1738         kfree(iocq);
1739 
1740         return ret;
1741 }
1742 
1743 void
1744 aoecmd_exit(void)
1745 {
1746         int i;
1747 
1748         for (i = 0; i < ncpus; i++)
1749                 if (kts[i].active)
1750                         aoe_ktstop(&kts[i]);
1751 
1752         aoe_flush_iocq();
1753 
1754         /* Free up the iocq and thread speicific configuration
1755         * allocated during startup.
1756         */
1757         kfree(iocq);
1758         kfree(kts);
1759         kfree(ktiowq);
1760 
1761         free_page((unsigned long) page_address(empty_page));
1762         empty_page = NULL;
1763 }
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/block/aoe/aoecmd.c

DEFINITIONS
