drivers/block/aoe/aoecmd.c

   1 /* Copyright (c) 2007 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/hdreg.h>
   9 #include <linux/blkdev.h>
  10 #include <linux/skbuff.h>
  11 #include <linux/netdevice.h>
  12 #include <linux/genhd.h>
  13 #include <linux/moduleparam.h>
  14 #include <net/net_namespace.h>
  15 #include <asm/unaligned.h>
  16 #include "aoe.h"
  17
  18 static int aoe_deadsecs = 60 * 3;
  19 module_param(aoe_deadsecs, int, 0644);
  20 MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev.");
  21
  22 static int aoe_maxout = 16;
  23 module_param(aoe_maxout, int, 0644);
  24 MODULE_PARM_DESC(aoe_maxout,
  25         "Only aoe_maxout outstanding packets for every MAC on eX.Y.");
  26
  27 static struct sk_buff *
  28 new_skb(ulong len)
  29 {
  30         struct sk_buff *skb;
  31
  32         skb = alloc_skb(len, GFP_ATOMIC);
  33         if (skb) {
  34                 skb_reset_mac_header(skb);
  35                 skb_reset_network_header(skb);
  36                 skb->protocol = __constant_htons(ETH_P_AOE);
  37                 skb->priority = 0;
  38                 skb->next = skb->prev = NULL;
  39
  40                 /* tell the network layer not to perform IP checksums
  41                  * or to get the NIC to do it
  42                  */
  43                 skb->ip_summed = CHECKSUM_NONE;
  44         }
  45         return skb;
  46 }
  47
  48 static struct frame *
  49 getframe(struct aoetgt *t, int tag)
  50 {
  51         struct frame *f, *e;
  52
  53         f = t->frames;
  54         e = f + t->nframes;
  55         for (; f<e; f++)
  56                 if (f->tag == tag)
  57                         return f;
  58         return NULL;
  59 }
  60
  61 /*
  62  * Leave the top bit clear so we have tagspace for userland.
  63  * The bottom 16 bits are the xmit tick for rexmit/rttavg processing.
  64  * This driver reserves tag -1 to mean "unused frame."
  65  */
  66 static int
  67 newtag(struct aoetgt *t)
  68 {
  69         register ulong n;
  70
  71         n = jiffies & 0xffff;
  72         return n |= (++t->lasttag & 0x7fff) << 16;
  73 }
  74
  75 static int
  76 aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)
  77 {
  78         u32 host_tag = newtag(t);
  79
  80         memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
  81         memcpy(h->dst, t->addr, sizeof h->dst);
  82         h->type = __constant_cpu_to_be16(ETH_P_AOE);
  83         h->verfl = AOE_HVER;
  84         h->major = cpu_to_be16(d->aoemajor);
  85         h->minor = d->aoeminor;
  86         h->cmd = AOECMD_ATA;
  87         h->tag = cpu_to_be32(host_tag);
  88
  89         return host_tag;
  90 }
  91
  92 static inline void
  93 put_lba(struct aoe_atahdr *ah, sector_t lba)
  94 {
  95         ah->lba0 = lba;
  96         ah->lba1 = lba >>= 8;
  97         ah->lba2 = lba >>= 8;
  98         ah->lba3 = lba >>= 8;
  99         ah->lba4 = lba >>= 8;
 100         ah->lba5 = lba >>= 8;
 101 }
 102
 103 static void
 104 ifrotate(struct aoetgt *t)
 105 {
 106         t->ifp++;
 107         if (t->ifp >= &t->ifs[NAOEIFS] || t->ifp->nd == NULL)
 108                 t->ifp = t->ifs;
 109         if (t->ifp->nd == NULL) {
 110                 printk(KERN_INFO "aoe: no interface to rotate to\n");
 111                 BUG();
 112         }
 113 }
 114
 115 static void
 116 skb_pool_put(struct aoedev *d, struct sk_buff *skb)
 117 {
 118         __skb_queue_tail(&d->skbpool, skb);
 119 }
 120
 121 static struct sk_buff *
 122 skb_pool_get(struct aoedev *d)
 123 {
 124         struct sk_buff *skb = skb_peek(&d->skbpool);
 125
 126         if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) {
 127                 __skb_unlink(skb, &d->skbpool);
 128                 return skb;
 129         }
 130         if (skb_queue_len(&d->skbpool) < NSKBPOOLMAX &&
 131             (skb = new_skb(ETH_ZLEN)))
 132                 return skb;
 133
 134         return NULL;
 135 }
 136
 137 /* freeframe is where we do our load balancing so it's a little hairy. */
 138 static struct frame *
 139 freeframe(struct aoedev *d)
 140 {
 141         struct frame *f, *e, *rf;
 142         struct aoetgt **t;
 143         struct sk_buff *skb;
 144
 145         if (d->targets[0] == NULL) {    /* shouldn't happen, but I'm paranoid */
 146                 printk(KERN_ERR "aoe: NULL TARGETS!\n");
 147                 return NULL;
 148         }
 149         t = d->tgt;
 150         t++;
 151         if (t >= &d->targets[NTARGETS] || !*t)
 152                 t = d->targets;
 153         for (;;) {
 154                 if ((*t)->nout < (*t)->maxout
 155                 && t != d->htgt
 156                 && (*t)->ifp->nd) {
 157                         rf = NULL;
 158                         f = (*t)->frames;
 159                         e = f + (*t)->nframes;
 160                         for (; f < e; f++) {
 161                                 if (f->tag != FREETAG)
 162                                         continue;
 163                                 skb = f->skb;
 164                                 if (!skb
 165                                 && !(f->skb = skb = new_skb(ETH_ZLEN)))
 166                                         continue;
 167                                 if (atomic_read(&skb_shinfo(skb)->dataref)
 168                                         != 1) {
 169                                         if (!rf)
 170                                                 rf = f;
 171                                         continue;
 172                                 }
 173 gotone:                         skb_shinfo(skb)->nr_frags = skb->data_len = 0;
 174                                 skb_trim(skb, 0);
 175                                 d->tgt = t;
 176                                 ifrotate(*t);
 177                                 return f;
 178                         }
 179                         /* Work can be done, but the network layer is
 180                            holding our precious packets.  Try to grab
 181                            one from the pool. */
 182                         f = rf;
 183                         if (f == NULL) {        /* more paranoia */
 184                                 printk(KERN_ERR
 185                                         "aoe: freeframe: %s.\n",
 186                                         "unexpected null rf");
 187                                 d->flags |= DEVFL_KICKME;
 188                                 return NULL;
 189                         }
 190                         skb = skb_pool_get(d);
 191                         if (skb) {
 192                                 skb_pool_put(d, f->skb);
 193                                 f->skb = skb;
 194                                 goto gotone;
 195                         }
 196                         (*t)->dataref++;
 197                         if ((*t)->nout == 0)
 198                                 d->flags |= DEVFL_KICKME;
 199                 }
 200                 if (t == d->tgt)        /* we've looped and found nada */
 201                         break;
 202                 t++;
 203                 if (t >= &d->targets[NTARGETS] || !*t)
 204                         t = d->targets;
 205         }
 206         return NULL;
 207 }
 208
 209 static int
 210 aoecmd_ata_rw(struct aoedev *d)
 211 {
 212         struct frame *f;
 213         struct aoe_hdr *h;
 214         struct aoe_atahdr *ah;
 215         struct buf *buf;
 216         struct bio_vec *bv;
 217         struct aoetgt *t;
 218         struct sk_buff *skb;
 219         ulong bcnt;
 220         char writebit, extbit;
 221
 222         writebit = 0x10;
 223         extbit = 0x4;
 224
 225         f = freeframe(d);
 226         if (f == NULL)
 227                 return 0;
 228         t = *d->tgt;
 229         buf = d->inprocess;
 230         bv = buf->bv;
 231         bcnt = t->ifp->maxbcnt;
 232         if (bcnt == 0)
 233                 bcnt = DEFAULTBCNT;
 234         if (bcnt > buf->bv_resid)
 235                 bcnt = buf->bv_resid;
 236         /* initialize the headers & frame */
 237         skb = f->skb;
 238         h = (struct aoe_hdr *) skb_mac_header(skb);
 239         ah = (struct aoe_atahdr *) (h+1);
 240         skb_put(skb, sizeof *h + sizeof *ah);
 241         memset(h, 0, skb->len);
 242         f->tag = aoehdr_atainit(d, t, h);
 243         t->nout++;
 244         f->waited = 0;
 245         f->buf = buf;
 246         f->bufaddr = page_address(bv->bv_page) + buf->bv_off;
 247         f->bcnt = bcnt;
 248         f->lba = buf->sector;
 249
 250         /* set up ata header */
 251         ah->scnt = bcnt >> 9;
 252         put_lba(ah, buf->sector);
 253         if (d->flags & DEVFL_EXT) {
 254                 ah->aflags |= AOEAFL_EXT;
 255         } else {
 256                 extbit = 0;
 257                 ah->lba3 &= 0x0f;
 258                 ah->lba3 |= 0xe0;       /* LBA bit + obsolete 0xa0 */
 259         }
 260         if (bio_data_dir(buf->bio) == WRITE) {
 261                 skb_fill_page_desc(skb, 0, bv->bv_page, buf->bv_off, bcnt);
 262                 ah->aflags |= AOEAFL_WRITE;
 263                 skb->len += bcnt;
 264                 skb->data_len = bcnt;
 265                 t->wpkts++;
 266         } else {
 267                 t->rpkts++;
 268                 writebit = 0;
 269         }
 270
 271         ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit;
 272
 273         /* mark all tracking fields and load out */
 274         buf->nframesout += 1;
 275         buf->bv_off += bcnt;
 276         buf->bv_resid -= bcnt;
 277         buf->resid -= bcnt;
 278         buf->sector += bcnt >> 9;
 279         if (buf->resid == 0) {
 280                 d->inprocess = NULL;
 281         } else if (buf->bv_resid == 0) {
 282                 buf->bv = ++bv;
 283                 buf->bv_resid = bv->bv_len;
 284                 WARN_ON(buf->bv_resid == 0);
 285                 buf->bv_off = bv->bv_offset;
 286         }
 287
 288         skb->dev = t->ifp->nd;
 289         skb = skb_clone(skb, GFP_ATOMIC);
 290         if (skb)
 291                 __skb_queue_tail(&d->sendq, skb);
 292         return 1;
 293 }
 294
 295 /* some callers cannot sleep, and they can call this function,
 296  * transmitting the packets later, when interrupts are on
 297  */
 298 static void
 299 aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue)
 300 {
 301         struct aoe_hdr *h;
 302         struct aoe_cfghdr *ch;
 303         struct sk_buff *skb;
 304         struct net_device *ifp;
 305
 306         read_lock(&dev_base_lock);
 307         for_each_netdev(&init_net, ifp) {
 308                 dev_hold(ifp);
 309                 if (!is_aoe_netif(ifp))
 310                         goto cont;
 311
 312                 skb = new_skb(sizeof *h + sizeof *ch);
 313                 if (skb == NULL) {
 314                         printk(KERN_INFO "aoe: skb alloc failure\n");
 315                         goto cont;
 316                 }
 317                 skb_put(skb, sizeof *h + sizeof *ch);
 318                 skb->dev = ifp;
 319                 __skb_queue_tail(queue, skb);
 320                 h = (struct aoe_hdr *) skb_mac_header(skb);
 321                 memset(h, 0, sizeof *h + sizeof *ch);
 322
 323                 memset(h->dst, 0xff, sizeof h->dst);
 324                 memcpy(h->src, ifp->dev_addr, sizeof h->src);
 325                 h->type = __constant_cpu_to_be16(ETH_P_AOE);
 326                 h->verfl = AOE_HVER;
 327                 h->major = cpu_to_be16(aoemajor);
 328                 h->minor = aoeminor;
 329                 h->cmd = AOECMD_CFG;
 330
 331 cont:
 332                 dev_put(ifp);
 333         }
 334         read_unlock(&dev_base_lock);
 335 }
 336
 337 static void
 338 resend(struct aoedev *d, struct aoetgt *t, struct frame *f)
 339 {
 340         struct sk_buff *skb;
 341         struct aoe_hdr *h;
 342         struct aoe_atahdr *ah;
 343         char buf[128];
 344         u32 n;
 345
 346         ifrotate(t);
 347         n = newtag(t);
 348         skb = f->skb;
 349         h = (struct aoe_hdr *) skb_mac_header(skb);
 350         ah = (struct aoe_atahdr *) (h+1);
 351
 352         snprintf(buf, sizeof buf,
 353                 "%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n",
 354                 "retransmit", d->aoemajor, d->aoeminor, f->tag, jiffies, n,
 355                 h->src, h->dst, t->nout);
 356         aoechr_error(buf);
 357
 358         f->tag = n;
 359         h->tag = cpu_to_be32(n);
 360         memcpy(h->dst, t->addr, sizeof h->dst);
 361         memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
 362
 363         switch (ah->cmdstat) {
 364         default:
 365                 break;
 366         case ATA_CMD_PIO_READ:
 367         case ATA_CMD_PIO_READ_EXT:
 368         case ATA_CMD_PIO_WRITE:
 369         case ATA_CMD_PIO_WRITE_EXT:
 370                 put_lba(ah, f->lba);
 371
 372                 n = f->bcnt;
 373                 if (n > DEFAULTBCNT)
 374                         n = DEFAULTBCNT;
 375                 ah->scnt = n >> 9;
 376                 if (ah->aflags & AOEAFL_WRITE) {
 377                         skb_fill_page_desc(skb, 0, virt_to_page(f->bufaddr),
 378                                 offset_in_page(f->bufaddr), n);
 379                         skb->len = sizeof *h + sizeof *ah + n;
 380                         skb->data_len = n;
 381                 }
 382         }
 383         skb->dev = t->ifp->nd;
 384         skb = skb_clone(skb, GFP_ATOMIC);
 385         if (skb == NULL)
 386                 return;
 387         __skb_queue_tail(&d->sendq, skb);
 388 }
 389
 390 static int
 391 tsince(int tag)
 392 {
 393         int n;
 394
 395         n = jiffies & 0xffff;
 396         n -= tag & 0xffff;
 397         if (n < 0)
 398                 n += 1<<16;
 399         return n;
 400 }
 401
 402 static struct aoeif *
 403 getif(struct aoetgt *t, struct net_device *nd)
 404 {
 405         struct aoeif *p, *e;
 406
 407         p = t->ifs;
 408         e = p + NAOEIFS;
 409         for (; p < e; p++)
 410                 if (p->nd == nd)
 411                         return p;
 412         return NULL;
 413 }
 414
 415 static struct aoeif *
 416 addif(struct aoetgt *t, struct net_device *nd)
 417 {
 418         struct aoeif *p;
 419
 420         p = getif(t, NULL);
 421         if (!p)
 422                 return NULL;
 423         p->nd = nd;
 424         p->maxbcnt = DEFAULTBCNT;
 425         p->lost = 0;
 426         p->lostjumbo = 0;
 427         return p;
 428 }
 429
 430 static void
 431 ejectif(struct aoetgt *t, struct aoeif *ifp)
 432 {
 433         struct aoeif *e;
 434         ulong n;
 435
 436         e = t->ifs + NAOEIFS - 1;
 437         n = (e - ifp) * sizeof *ifp;
 438         memmove(ifp, ifp+1, n);
 439         e->nd = NULL;
 440 }
 441
 442 static int
 443 sthtith(struct aoedev *d)
 444 {
 445         struct frame *f, *e, *nf;
 446         struct sk_buff *skb;
 447         struct aoetgt *ht = *d->htgt;
 448
 449         f = ht->frames;
 450         e = f + ht->nframes;
 451         for (; f < e; f++) {
 452                 if (f->tag == FREETAG)
 453                         continue;
 454                 nf = freeframe(d);
 455                 if (!nf)
 456                         return 0;
 457                 skb = nf->skb;
 458                 *nf = *f;
 459                 f->skb = skb;
 460                 f->tag = FREETAG;
 461                 nf->waited = 0;
 462                 ht->nout--;
 463                 (*d->tgt)->nout++;
 464                 resend(d, *d->tgt, nf);
 465         }
 466         /* he's clean, he's useless.  take away his interfaces */
 467         memset(ht->ifs, 0, sizeof ht->ifs);
 468         d->htgt = NULL;
 469         return 1;
 470 }
 471
 472 static inline unsigned char
 473 ata_scnt(unsigned char *packet) {
 474         struct aoe_hdr *h;
 475         struct aoe_atahdr *ah;
 476
 477         h = (struct aoe_hdr *) packet;
 478         ah = (struct aoe_atahdr *) (h+1);
 479         return ah->scnt;
 480 }
 481
 482 static void
 483 rexmit_timer(ulong vp)
 484 {
 485         struct sk_buff_head queue;
 486         struct aoedev *d;
 487         struct aoetgt *t, **tt, **te;
 488         struct aoeif *ifp;
 489         struct frame *f, *e;
 490         register long timeout;
 491         ulong flags, n;
 492
 493         d = (struct aoedev *) vp;
 494
 495         /* timeout is always ~150% of the moving average */
 496         timeout = d->rttavg;
 497         timeout += timeout >> 1;
 498
 499         spin_lock_irqsave(&d->lock, flags);
 500
 501         if (d->flags & DEVFL_TKILL) {
 502                 spin_unlock_irqrestore(&d->lock, flags);
 503                 return;
 504         }
 505         tt = d->targets;
 506         te = tt + NTARGETS;
 507         for (; tt < te && *tt; tt++) {
 508                 t = *tt;
 509                 f = t->frames;
 510                 e = f + t->nframes;
 511                 for (; f < e; f++) {
 512                         if (f->tag == FREETAG
 513                         || tsince(f->tag) < timeout)
 514                                 continue;
 515                         n = f->waited += timeout;
 516                         n /= HZ;
 517                         if (n > aoe_deadsecs) {
 518                                 /* waited too long.  device failure. */
 519                                 aoedev_downdev(d);
 520                                 break;
 521                         }
 522
 523                         if (n > HELPWAIT /* see if another target can help */
 524                         && (tt != d->targets || d->targets[1]))
 525                                 d->htgt = tt;
 526
 527                         if (t->nout == t->maxout) {
 528                                 if (t->maxout > 1)
 529                                         t->maxout--;
 530                                 t->lastwadj = jiffies;
 531                         }
 532
 533                         ifp = getif(t, f->skb->dev);
 534                         if (ifp && ++ifp->lost > (t->nframes << 1)
 535                         && (ifp != t->ifs || t->ifs[1].nd)) {
 536                                 ejectif(t, ifp);
 537                                 ifp = NULL;
 538                         }
 539
 540                         if (ata_scnt(skb_mac_header(f->skb)) > DEFAULTBCNT / 512
 541                         && ifp && ++ifp->lostjumbo > (t->nframes << 1)
 542                         && ifp->maxbcnt != DEFAULTBCNT) {
 543                                 printk(KERN_INFO
 544                                         "aoe: e%ld.%d: "
 545                                         "too many lost jumbo on "
 546                                         "%s:%pm - "
 547                                         "falling back to %d frames.\n",
 548                                         d->aoemajor, d->aoeminor,
 549                                         ifp->nd->name, t->addr,
 550                                         DEFAULTBCNT);
 551                                 ifp->maxbcnt = 0;
 552                         }
 553                         resend(d, t, f);
 554                 }
 555
 556                 /* window check */
 557                 if (t->nout == t->maxout
 558                 && t->maxout < t->nframes
 559                 && (jiffies - t->lastwadj)/HZ > 10) {
 560                         t->maxout++;
 561                         t->lastwadj = jiffies;
 562                 }
 563         }
 564
 565         if (!skb_queue_empty(&d->sendq)) {
 566                 n = d->rttavg <<= 1;
 567                 if (n > MAXTIMER)
 568                         d->rttavg = MAXTIMER;
 569         }
 570
 571         if (d->flags & DEVFL_KICKME || d->htgt) {
 572                 d->flags &= ~DEVFL_KICKME;
 573                 aoecmd_work(d);
 574         }
 575
 576         __skb_queue_head_init(&queue);
 577         skb_queue_splice_init(&d->sendq, &queue);
 578
 579         d->timer.expires = jiffies + TIMERTICK;
 580         add_timer(&d->timer);
 581
 582         spin_unlock_irqrestore(&d->lock, flags);
 583
 584         aoenet_xmit(&queue);
 585 }
 586
 587 /* enters with d->lock held */
 588 void
 589 aoecmd_work(struct aoedev *d)
 590 {
 591         struct buf *buf;
 592 loop:
 593         if (d->htgt && !sthtith(d))
 594                 return;
 595         if (d->inprocess == NULL) {
 596                 if (list_empty(&d->bufq))
 597                         return;
 598                 buf = container_of(d->bufq.next, struct buf, bufs);
 599                 list_del(d->bufq.next);
 600                 d->inprocess = buf;
 601         }
 602         if (aoecmd_ata_rw(d))
 603                 goto loop;
 604 }
 605
 606 /* this function performs work that has been deferred until sleeping is OK
 607  */
 608 void
 609 aoecmd_sleepwork(struct work_struct *work)
 610 {
 611         struct aoedev *d = container_of(work, struct aoedev, work);
 612
 613         if (d->flags & DEVFL_GDALLOC)
 614                 aoeblk_gdalloc(d);
 615
 616         if (d->flags & DEVFL_NEWSIZE) {
 617                 struct block_device *bd;
 618                 unsigned long flags;
 619                 u64 ssize;
 620
 621                 ssize = get_capacity(d->gd);
 622                 bd = bdget_disk(d->gd, 0);
 623
 624                 if (bd) {
 625                         mutex_lock(&bd->bd_inode->i_mutex);
 626                         i_size_write(bd->bd_inode, (loff_t)ssize<<9);
 627                         mutex_unlock(&bd->bd_inode->i_mutex);
 628                         bdput(bd);
 629                 }
 630                 spin_lock_irqsave(&d->lock, flags);
 631                 d->flags |= DEVFL_UP;
 632                 d->flags &= ~DEVFL_NEWSIZE;
 633                 spin_unlock_irqrestore(&d->lock, flags);
 634         }
 635 }
 636
 637 static void
 638 ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
 639 {
 640         u64 ssize;
 641         u16 n;
 642
 643         /* word 83: command set supported */
 644         n = get_unaligned_le16(&id[83 << 1]);
 645
 646         /* word 86: command set/feature enabled */
 647         n |= get_unaligned_le16(&id[86 << 1]);
 648
 649         if (n & (1<<10)) {      /* bit 10: LBA 48 */
 650                 d->flags |= DEVFL_EXT;
 651
 652                 /* word 100: number lba48 sectors */
 653                 ssize = get_unaligned_le64(&id[100 << 1]);
 654
 655                 /* set as in ide-disk.c:init_idedisk_capacity */
 656                 d->geo.cylinders = ssize;
 657                 d->geo.cylinders /= (255 * 63);
 658                 d->geo.heads = 255;
 659                 d->geo.sectors = 63;
 660         } else {
 661                 d->flags &= ~DEVFL_EXT;
 662
 663                 /* number lba28 sectors */
 664                 ssize = get_unaligned_le32(&id[60 << 1]);
 665
 666                 /* NOTE: obsolete in ATA 6 */
 667                 d->geo.cylinders = get_unaligned_le16(&id[54 << 1]);
 668                 d->geo.heads = get_unaligned_le16(&id[55 << 1]);
 669                 d->geo.sectors = get_unaligned_le16(&id[56 << 1]);
 670         }
 671
 672         if (d->ssize != ssize)
 673                 printk(KERN_INFO
 674                         "aoe: %pm e%ld.%d v%04x has %llu sectors\n",
 675                         t->addr,
 676                         d->aoemajor, d->aoeminor,
 677                         d->fw_ver, (long long)ssize);
 678         d->ssize = ssize;
 679         d->geo.start = 0;
 680         if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
 681                 return;
 682         if (d->gd != NULL) {
 683                 set_capacity(d->gd, ssize);
 684                 d->flags |= DEVFL_NEWSIZE;
 685         } else
 686                 d->flags |= DEVFL_GDALLOC;
 687         schedule_work(&d->work);
 688 }
 689
 690 static void
 691 calc_rttavg(struct aoedev *d, int rtt)
 692 {
 693         register long n;
 694
 695         n = rtt;
 696         if (n < 0) {
 697                 n = -rtt;
 698                 if (n < MINTIMER)
 699                         n = MINTIMER;
 700                 else if (n > MAXTIMER)
 701                         n = MAXTIMER;
 702                 d->mintimer += (n - d->mintimer) >> 1;
 703         } else if (n < d->mintimer)
 704                 n = d->mintimer;
 705         else if (n > MAXTIMER)
 706                 n = MAXTIMER;
 707
 708         /* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
 709         n -= d->rttavg;
 710         d->rttavg += n >> 2;
 711 }
 712
 713 static struct aoetgt *
 714 gettgt(struct aoedev *d, char *addr)
 715 {
 716         struct aoetgt **t, **e;
 717
 718         t = d->targets;
 719         e = t + NTARGETS;
 720         for (; t < e && *t; t++)
 721                 if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0)
 722                         return *t;
 723         return NULL;
 724 }
 725
 726 static inline void
 727 diskstats(struct gendisk *disk, struct bio *bio, ulong duration, sector_t sector)
 728 {
 729         unsigned long n_sect = bio->bi_size >> 9;
 730         const int rw = bio_data_dir(bio);
 731         struct hd_struct *part;
 732         int cpu;
 733
 734         cpu = part_stat_lock();
 735         part = disk_map_sector_rcu(disk, sector);
 736
 737         part_stat_inc(cpu, part, ios[rw]);
 738         part_stat_add(cpu, part, ticks[rw], duration);
 739         part_stat_add(cpu, part, sectors[rw], n_sect);
 740         part_stat_add(cpu, part, io_ticks, duration);
 741
 742         part_stat_unlock();
 743 }
 744
 745 void
 746 aoecmd_ata_rsp(struct sk_buff *skb)
 747 {
 748         struct sk_buff_head queue;
 749         struct aoedev *d;
 750         struct aoe_hdr *hin, *hout;
 751         struct aoe_atahdr *ahin, *ahout;
 752         struct frame *f;
 753         struct buf *buf;
 754         struct aoetgt *t;
 755         struct aoeif *ifp;
 756         register long n;
 757         ulong flags;
 758         char ebuf[128];
 759         u16 aoemajor;
 760
 761         hin = (struct aoe_hdr *) skb_mac_header(skb);
 762         aoemajor = get_unaligned_be16(&hin->major);
 763         d = aoedev_by_aoeaddr(aoemajor, hin->minor);
 764         if (d == NULL) {
 765                 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
 766                         "for unknown device %d.%d\n",
 767                          aoemajor, hin->minor);
 768                 aoechr_error(ebuf);
 769                 return;
 770         }
 771
 772         spin_lock_irqsave(&d->lock, flags);
 773
 774         n = get_unaligned_be32(&hin->tag);
 775         t = gettgt(d, hin->src);
 776         if (t == NULL) {
 777                 printk(KERN_INFO "aoe: can't find target e%ld.%d:%pm\n",
 778                         d->aoemajor, d->aoeminor, hin->src);
 779                 spin_unlock_irqrestore(&d->lock, flags);
 780                 return;
 781         }
 782         f = getframe(t, n);
 783         if (f == NULL) {
 784                 calc_rttavg(d, -tsince(n));
 785                 spin_unlock_irqrestore(&d->lock, flags);
 786                 snprintf(ebuf, sizeof ebuf,
 787                         "%15s e%d.%d    tag=%08x@%08lx\n",
 788                         "unexpected rsp",
 789                         get_unaligned_be16(&hin->major),
 790                         hin->minor,
 791                         get_unaligned_be32(&hin->tag),
 792                         jiffies);
 793                 aoechr_error(ebuf);
 794                 return;
 795         }
 796
 797         calc_rttavg(d, tsince(f->tag));
 798
 799         ahin = (struct aoe_atahdr *) (hin+1);
 800         hout = (struct aoe_hdr *) skb_mac_header(f->skb);
 801         ahout = (struct aoe_atahdr *) (hout+1);
 802         buf = f->buf;
 803
 804         if (ahin->cmdstat & 0xa9) {     /* these bits cleared on success */
 805                 printk(KERN_ERR
 806                         "aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n",
 807                         ahout->cmdstat, ahin->cmdstat,
 808                         d->aoemajor, d->aoeminor);
 809                 if (buf)
 810                         buf->flags |= BUFFL_FAIL;
 811         } else {
 812                 if (d->htgt && t == *d->htgt) /* I'll help myself, thank you. */
 813                         d->htgt = NULL;
 814                 n = ahout->scnt << 9;
 815                 switch (ahout->cmdstat) {
 816                 case ATA_CMD_PIO_READ:
 817                 case ATA_CMD_PIO_READ_EXT:
 818                         if (skb->len - sizeof *hin - sizeof *ahin < n) {
 819                                 printk(KERN_ERR
 820                                         "aoe: %s.  skb->len=%d need=%ld\n",
 821                                         "runt data size in read", skb->len, n);
 822                                 /* fail frame f?  just returning will rexmit. */
 823                                 spin_unlock_irqrestore(&d->lock, flags);
 824                                 return;
 825                         }
 826                         memcpy(f->bufaddr, ahin+1, n);
 827                 case ATA_CMD_PIO_WRITE:
 828                 case ATA_CMD_PIO_WRITE_EXT:
 829                         ifp = getif(t, skb->dev);
 830                         if (ifp) {
 831                                 ifp->lost = 0;
 832                                 if (n > DEFAULTBCNT)
 833                                         ifp->lostjumbo = 0;
 834                         }
 835                         if (f->bcnt -= n) {
 836                                 f->lba += n >> 9;
 837                                 f->bufaddr += n;
 838                                 resend(d, t, f);
 839                                 goto xmit;
 840                         }
 841                         break;
 842                 case ATA_CMD_ID_ATA:
 843                         if (skb->len - sizeof *hin - sizeof *ahin < 512) {
 844                                 printk(KERN_INFO
 845                                         "aoe: runt data size in ataid.  skb->len=%d\n",
 846                                         skb->len);
 847                                 spin_unlock_irqrestore(&d->lock, flags);
 848                                 return;
 849                         }
 850                         ataid_complete(d, t, (char *) (ahin+1));
 851                         break;
 852                 default:
 853                         printk(KERN_INFO
 854                                 "aoe: unrecognized ata command %2.2Xh for %d.%d\n",
 855                                 ahout->cmdstat,
 856                                 get_unaligned_be16(&hin->major),
 857                                 hin->minor);
 858                 }
 859         }
 860
 861         if (buf && --buf->nframesout == 0 && buf->resid == 0) {
 862                 diskstats(d->gd, buf->bio, jiffies - buf->stime, buf->sector);
 863                 n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
 864                 bio_endio(buf->bio, n);
 865                 mempool_free(buf, d->bufpool);
 866         }
 867
 868         f->buf = NULL;
 869         f->tag = FREETAG;
 870         t->nout--;
 871
 872         aoecmd_work(d);
 873 xmit:
 874         __skb_queue_head_init(&queue);
 875         skb_queue_splice_init(&d->sendq, &queue);
 876
 877         spin_unlock_irqrestore(&d->lock, flags);
 878         aoenet_xmit(&queue);
 879 }
 880
 881 void
 882 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
 883 {
 884         struct sk_buff_head queue;
 885
 886         __skb_queue_head_init(&queue);
 887         aoecmd_cfg_pkts(aoemajor, aoeminor, &queue);
 888         aoenet_xmit(&queue);
 889 }
 890
 891 struct sk_buff *
 892 aoecmd_ata_id(struct aoedev *d)
 893 {
 894         struct aoe_hdr *h;
 895         struct aoe_atahdr *ah;
 896         struct frame *f;
 897         struct sk_buff *skb;
 898         struct aoetgt *t;
 899
 900         f = freeframe(d);
 901         if (f == NULL)
 902                 return NULL;
 903
 904         t = *d->tgt;
 905
 906         /* initialize the headers & frame */
 907         skb = f->skb;
 908         h = (struct aoe_hdr *) skb_mac_header(skb);
 909         ah = (struct aoe_atahdr *) (h+1);
 910         skb_put(skb, sizeof *h + sizeof *ah);
 911         memset(h, 0, skb->len);
 912         f->tag = aoehdr_atainit(d, t, h);
 913         t->nout++;
 914         f->waited = 0;
 915
 916         /* set up ata header */
 917         ah->scnt = 1;
 918         ah->cmdstat = ATA_CMD_ID_ATA;
 919         ah->lba3 = 0xa0;
 920
 921         skb->dev = t->ifp->nd;
 922
 923         d->rttavg = MAXTIMER;
 924         d->timer.function = rexmit_timer;
 925
 926         return skb_clone(skb, GFP_ATOMIC);
 927 }
 928
 929 static struct aoetgt *
 930 addtgt(struct aoedev *d, char *addr, ulong nframes)
 931 {
 932         struct aoetgt *t, **tt, **te;
 933         struct frame *f, *e;
 934
 935         tt = d->targets;
 936         te = tt + NTARGETS;
 937         for (; tt < te && *tt; tt++)
 938                 ;
 939
 940         if (tt == te) {
 941                 printk(KERN_INFO
 942                         "aoe: device addtgt failure; too many targets\n");
 943                 return NULL;
 944         }
 945         t = kcalloc(1, sizeof *t, GFP_ATOMIC);
 946         f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
 947         if (!t || !f) {
 948                 kfree(f);
 949                 kfree(t);
 950                 printk(KERN_INFO "aoe: cannot allocate memory to add target\n");
 951                 return NULL;
 952         }
 953
 954         t->nframes = nframes;
 955         t->frames = f;
 956         e = f + nframes;
 957         for (; f < e; f++)
 958                 f->tag = FREETAG;
 959         memcpy(t->addr, addr, sizeof t->addr);
 960         t->ifp = t->ifs;
 961         t->maxout = t->nframes;
 962         return *tt = t;
 963 }
 964
 965 void
 966 aoecmd_cfg_rsp(struct sk_buff *skb)
 967 {
 968         struct aoedev *d;
 969         struct aoe_hdr *h;
 970         struct aoe_cfghdr *ch;
 971         struct aoetgt *t;
 972         struct aoeif *ifp;
 973         ulong flags, sysminor, aoemajor;
 974         struct sk_buff *sl;
 975         u16 n;
 976
 977         h = (struct aoe_hdr *) skb_mac_header(skb);
 978         ch = (struct aoe_cfghdr *) (h+1);
 979
 980         /*
 981          * Enough people have their dip switches set backwards to
 982          * warrant a loud message for this special case.
 983          */
 984         aoemajor = get_unaligned_be16(&h->major);
 985         if (aoemajor == 0xfff) {
 986                 printk(KERN_ERR "aoe: Warning: shelf address is all ones.  "
 987                         "Check shelf dip switches.\n");
 988                 return;
 989         }
 990
 991         sysminor = SYSMINOR(aoemajor, h->minor);
 992         if (sysminor * AOE_PARTITIONS + AOE_PARTITIONS > MINORMASK) {
 993                 printk(KERN_INFO "aoe: e%ld.%d: minor number too large\n",
 994                         aoemajor, (int) h->minor);
 995                 return;
 996         }
 997
 998         n = be16_to_cpu(ch->bufcnt);
 999         if (n > aoe_maxout)     /* keep it reasonable */
1000                 n = aoe_maxout;
1001
1002         d = aoedev_by_sysminor_m(sysminor);
1003         if (d == NULL) {
1004                 printk(KERN_INFO "aoe: device sysminor_m failure\n");
1005                 return;
1006         }
1007
1008         spin_lock_irqsave(&d->lock, flags);
1009
1010         t = gettgt(d, h->src);
1011         if (!t) {
1012                 t = addtgt(d, h->src, n);
1013                 if (!t) {
1014                         spin_unlock_irqrestore(&d->lock, flags);
1015                         return;
1016                 }
1017         }
1018         ifp = getif(t, skb->dev);
1019         if (!ifp) {
1020                 ifp = addif(t, skb->dev);
1021                 if (!ifp) {
1022                         printk(KERN_INFO
1023                                 "aoe: device addif failure; "
1024                                 "too many interfaces?\n");
1025                         spin_unlock_irqrestore(&d->lock, flags);
1026                         return;
1027                 }
1028         }
1029         if (ifp->maxbcnt) {
1030                 n = ifp->nd->mtu;
1031                 n -= sizeof (struct aoe_hdr) + sizeof (struct aoe_atahdr);
1032                 n /= 512;
1033                 if (n > ch->scnt)
1034                         n = ch->scnt;
1035                 n = n ? n * 512 : DEFAULTBCNT;
1036                 if (n != ifp->maxbcnt) {
1037                         printk(KERN_INFO
1038                                 "aoe: e%ld.%d: setting %d%s%s:%pm\n",
1039                                 d->aoemajor, d->aoeminor, n,
1040                                 " byte data frames on ", ifp->nd->name,
1041                                 t->addr);
1042                         ifp->maxbcnt = n;
1043                 }
1044         }
1045
1046         /* don't change users' perspective */
1047         if (d->nopen) {
1048                 spin_unlock_irqrestore(&d->lock, flags);
1049                 return;
1050         }
1051         d->fw_ver = be16_to_cpu(ch->fwver);
1052
1053         sl = aoecmd_ata_id(d);
1054
1055         spin_unlock_irqrestore(&d->lock, flags);
1056
1057         if (sl) {
1058                 struct sk_buff_head queue;
1059                 __skb_queue_head_init(&queue);
1060                 __skb_queue_tail(&queue, sl);
1061                 aoenet_xmit(&queue);
1062         }
1063 }
1064
1065 void
1066 aoecmd_cleanslate(struct aoedev *d)
1067 {
1068         struct aoetgt **t, **te;
1069         struct aoeif *p, *e;
1070
1071         d->mintimer = MINTIMER;
1072
1073         t = d->targets;
1074         te = t + NTARGETS;
1075         for (; t < te && *t; t++) {
1076                 (*t)->maxout = (*t)->nframes;
1077                 p = (*t)->ifs;
1078                 e = p + NAOEIFS;
1079                 for (; p < e; p++) {
1080                         p->lostjumbo = 0;
1081                         p->lost = 0;
1082                         p->maxbcnt = DEFAULTBCNT;
1083                 }
1084         }
1085 }