release/src-rt-6.x.4708/linux/linux-2.6.36/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/slab.h>
   9 #include <linux/hdreg.h>
  10 #include <linux/blkdev.h>
  11 #include <linux/skbuff.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/genhd.h>
  14 #include <linux/moduleparam.h>
  15 #include <net/net_namespace.h>
  16 #include <asm/unaligned.h>
  17 #include "aoe.h"
  18
  19 static int aoe_deadsecs = 60 * 3;
  20 module_param(aoe_deadsecs, int, 0644);
  21 MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev.");
  22
  23 static int aoe_maxout = 16;
  24 module_param(aoe_maxout, int, 0644);
  25 MODULE_PARM_DESC(aoe_maxout,
  26         "Only aoe_maxout outstanding packets for every MAC on eX.Y.");
  27
  28 static struct sk_buff *
  29 new_skb(ulong len)
  30 {
  31         struct sk_buff *skb;
  32
  33         skb = alloc_skb(len, GFP_ATOMIC);
  34         if (skb) {
  35                 skb_reset_mac_header(skb);
  36                 skb_reset_network_header(skb);
  37                 skb->protocol = __constant_htons(ETH_P_AOE);
  38         }
  39         return skb;
  40 }
  41
  42 static struct frame *
  43 getframe(struct aoetgt *t, int tag)
  44 {
  45         struct frame *f, *e;
  46
  47         f = t->frames;
  48         e = f + t->nframes;
  49         for (; f<e; f++)
  50                 if (f->tag == tag)
  51                         return f;
  52         return NULL;
  53 }
  54
  55 /*
  56  * Leave the top bit clear so we have tagspace for userland.
  57  * The bottom 16 bits are the xmit tick for rexmit/rttavg processing.
  58  * This driver reserves tag -1 to mean "unused frame."
  59  */
  60 static int
  61 newtag(struct aoetgt *t)
  62 {
  63         register ulong n;
  64
  65         n = jiffies & 0xffff;
  66         return n |= (++t->lasttag & 0x7fff) << 16;
  67 }
  68
  69 static int
  70 aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)
  71 {
  72         u32 host_tag = newtag(t);
  73
  74         memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
  75         memcpy(h->dst, t->addr, sizeof h->dst);
  76         h->type = __constant_cpu_to_be16(ETH_P_AOE);
  77         h->verfl = AOE_HVER;
  78         h->major = cpu_to_be16(d->aoemajor);
  79         h->minor = d->aoeminor;
  80         h->cmd = AOECMD_ATA;
  81         h->tag = cpu_to_be32(host_tag);
  82
  83         return host_tag;
  84 }
  85
  86 static inline void
  87 put_lba(struct aoe_atahdr *ah, sector_t lba)
  88 {
  89         ah->lba0 = lba;
  90         ah->lba1 = lba >>= 8;
  91         ah->lba2 = lba >>= 8;
  92         ah->lba3 = lba >>= 8;
  93         ah->lba4 = lba >>= 8;
  94         ah->lba5 = lba >>= 8;
  95 }
  96
  97 static void
  98 ifrotate(struct aoetgt *t)
  99 {
 100         t->ifp++;
 101         if (t->ifp >= &t->ifs[NAOEIFS] || t->ifp->nd == NULL)
 102                 t->ifp = t->ifs;
 103         if (t->ifp->nd == NULL) {
 104                 printk(KERN_INFO "aoe: no interface to rotate to\n");
 105                 BUG();
 106         }
 107 }
 108
 109 static void
 110 skb_pool_put(struct aoedev *d, struct sk_buff *skb)
 111 {
 112         __skb_queue_tail(&d->skbpool, skb);
 113 }
 114
 115 static struct sk_buff *
 116 skb_pool_get(struct aoedev *d)
 117 {
 118         struct sk_buff *skb = skb_peek(&d->skbpool);
 119
 120         if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) {
 121                 __skb_unlink(skb, &d->skbpool);
 122                 return skb;
 123         }
 124         if (skb_queue_len(&d->skbpool) < NSKBPOOLMAX &&
 125             (skb = new_skb(ETH_ZLEN)))
 126                 return skb;
 127
 128         return NULL;
 129 }
 130
 131 /* freeframe is where we do our load balancing so it's a little hairy. */
 132 static struct frame *
 133 freeframe(struct aoedev *d)
 134 {
 135         struct frame *f, *e, *rf;
 136         struct aoetgt **t;
 137         struct sk_buff *skb;
 138
 139         if (d->targets[0] == NULL) {    /* shouldn't happen, but I'm paranoid */
 140                 printk(KERN_ERR "aoe: NULL TARGETS!\n");
 141                 return NULL;
 142         }
 143         t = d->tgt;
 144         t++;
 145         if (t >= &d->targets[NTARGETS] || !*t)
 146                 t = d->targets;
 147         for (;;) {
 148                 if ((*t)->nout < (*t)->maxout
 149                 && t != d->htgt
 150                 && (*t)->ifp->nd) {
 151                         rf = NULL;
 152                         f = (*t)->frames;
 153                         e = f + (*t)->nframes;
 154                         for (; f < e; f++) {
 155                                 if (f->tag != FREETAG)
 156                                         continue;
 157                                 skb = f->skb;
 158                                 if (!skb
 159                                 && !(f->skb = skb = new_skb(ETH_ZLEN)))
 160                                         continue;
 161                                 if (atomic_read(&skb_shinfo(skb)->dataref)
 162                                         != 1) {
 163                                         if (!rf)
 164                                                 rf = f;
 165                                         continue;
 166                                 }
 167 gotone:                         skb_shinfo(skb)->nr_frags = skb->data_len = 0;
 168                                 skb_trim(skb, 0);
 169                                 d->tgt = t;
 170                                 ifrotate(*t);
 171                                 return f;
 172                         }
 173                         /* Work can be done, but the network layer is
 174                            holding our precious packets.  Try to grab
 175                            one from the pool. */
 176                         f = rf;
 177                         if (f == NULL) {        /* more paranoia */
 178                                 printk(KERN_ERR
 179                                         "aoe: freeframe: %s.\n",
 180                                         "unexpected null rf");
 181                                 d->flags |= DEVFL_KICKME;
 182                                 return NULL;
 183                         }
 184                         skb = skb_pool_get(d);
 185                         if (skb) {
 186                                 skb_pool_put(d, f->skb);
 187                                 f->skb = skb;
 188                                 goto gotone;
 189                         }
 190                         (*t)->dataref++;
 191                         if ((*t)->nout == 0)
 192                                 d->flags |= DEVFL_KICKME;
 193                 }
 194                 if (t == d->tgt)        /* we've looped and found nada */
 195                         break;
 196                 t++;
 197                 if (t >= &d->targets[NTARGETS] || !*t)
 198                         t = d->targets;
 199         }
 200         return NULL;
 201 }
 202
 203 static int
 204 aoecmd_ata_rw(struct aoedev *d)
 205 {
 206         struct frame *f;
 207         struct aoe_hdr *h;
 208         struct aoe_atahdr *ah;
 209         struct buf *buf;
 210         struct bio_vec *bv;
 211         struct aoetgt *t;
 212         struct sk_buff *skb;
 213         ulong bcnt;
 214         char writebit, extbit;
 215
 216         writebit = 0x10;
 217         extbit = 0x4;
 218
 219         f = freeframe(d);
 220         if (f == NULL)
 221                 return 0;
 222         t = *d->tgt;
 223         buf = d->inprocess;
 224         bv = buf->bv;
 225         bcnt = t->ifp->maxbcnt;
 226         if (bcnt == 0)
 227                 bcnt = DEFAULTBCNT;
 228         if (bcnt > buf->bv_resid)
 229                 bcnt = buf->bv_resid;
 230         /* initialize the headers & frame */
 231         skb = f->skb;
 232         h = (struct aoe_hdr *) skb_mac_header(skb);
 233         ah = (struct aoe_atahdr *) (h+1);
 234         skb_put(skb, sizeof *h + sizeof *ah);
 235         memset(h, 0, skb->len);
 236         f->tag = aoehdr_atainit(d, t, h);
 237         t->nout++;
 238         f->waited = 0;
 239         f->buf = buf;
 240         f->bufaddr = page_address(bv->bv_page) + buf->bv_off;
 241         f->bcnt = bcnt;
 242         f->lba = buf->sector;
 243
 244         /* set up ata header */
 245         ah->scnt = bcnt >> 9;
 246         put_lba(ah, buf->sector);
 247         if (d->flags & DEVFL_EXT) {
 248                 ah->aflags |= AOEAFL_EXT;
 249         } else {
 250                 extbit = 0;
 251                 ah->lba3 &= 0x0f;
 252                 ah->lba3 |= 0xe0;       /* LBA bit + obsolete 0xa0 */
 253         }
 254         if (bio_data_dir(buf->bio) == WRITE) {
 255                 skb_fill_page_desc(skb, 0, bv->bv_page, buf->bv_off, bcnt);
 256                 ah->aflags |= AOEAFL_WRITE;
 257                 skb->len += bcnt;
 258                 skb->data_len = bcnt;
 259                 t->wpkts++;
 260         } else {
 261                 t->rpkts++;
 262                 writebit = 0;
 263         }
 264
 265         ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit;
 266
 267         /* mark all tracking fields and load out */
 268         buf->nframesout += 1;
 269         buf->bv_off += bcnt;
 270         buf->bv_resid -= bcnt;
 271         buf->resid -= bcnt;
 272         buf->sector += bcnt >> 9;
 273         if (buf->resid == 0) {
 274                 d->inprocess = NULL;
 275         } else if (buf->bv_resid == 0) {
 276                 buf->bv = ++bv;
 277                 buf->bv_resid = bv->bv_len;
 278                 WARN_ON(buf->bv_resid == 0);
 279                 buf->bv_off = bv->bv_offset;
 280         }
 281
 282         skb->dev = t->ifp->nd;
 283         skb = skb_clone(skb, GFP_ATOMIC);
 284         if (skb)
 285                 __skb_queue_tail(&d->sendq, skb);
 286         return 1;
 287 }
 288
 289 /* some callers cannot sleep, and they can call this function,
 290  * transmitting the packets later, when interrupts are on
 291  */
 292 static void
 293 aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue)
 294 {
 295         struct aoe_hdr *h;
 296         struct aoe_cfghdr *ch;
 297         struct sk_buff *skb;
 298         struct net_device *ifp;
 299
 300         read_lock(&dev_base_lock);
 301         for_each_netdev(&init_net, ifp) {
 302                 dev_hold(ifp);
 303                 if (!is_aoe_netif(ifp))
 304                         goto cont;
 305
 306                 skb = new_skb(sizeof *h + sizeof *ch);
 307                 if (skb == NULL) {
 308                         printk(KERN_INFO "aoe: skb alloc failure\n");
 309                         goto cont;
 310                 }
 311                 skb_put(skb, sizeof *h + sizeof *ch);
 312                 skb->dev = ifp;
 313                 __skb_queue_tail(queue, skb);
 314                 h = (struct aoe_hdr *) skb_mac_header(skb);
 315                 memset(h, 0, sizeof *h + sizeof *ch);
 316
 317                 memset(h->dst, 0xff, sizeof h->dst);
 318                 memcpy(h->src, ifp->dev_addr, sizeof h->src);
 319                 h->type = __constant_cpu_to_be16(ETH_P_AOE);
 320                 h->verfl = AOE_HVER;
 321                 h->major = cpu_to_be16(aoemajor);
 322                 h->minor = aoeminor;
 323                 h->cmd = AOECMD_CFG;
 324
 325 cont:
 326                 dev_put(ifp);
 327         }
 328         read_unlock(&dev_base_lock);
 329 }
 330
 331 static void
 332 resend(struct aoedev *d, struct aoetgt *t, struct frame *f)
 333 {
 334         struct sk_buff *skb;
 335         struct aoe_hdr *h;
 336         struct aoe_atahdr *ah;
 337         char buf[128];
 338         u32 n;
 339
 340         ifrotate(t);
 341         n = newtag(t);
 342         skb = f->skb;
 343         h = (struct aoe_hdr *) skb_mac_header(skb);
 344         ah = (struct aoe_atahdr *) (h+1);
 345
 346         snprintf(buf, sizeof buf,
 347                 "%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n",
 348                 "retransmit", d->aoemajor, d->aoeminor, f->tag, jiffies, n,
 349                 h->src, h->dst, t->nout);
 350         aoechr_error(buf);
 351
 352         f->tag = n;
 353         h->tag = cpu_to_be32(n);
 354         memcpy(h->dst, t->addr, sizeof h->dst);
 355         memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
 356
 357         switch (ah->cmdstat) {
 358         default:
 359                 break;
 360         case ATA_CMD_PIO_READ:
 361         case ATA_CMD_PIO_READ_EXT:
 362         case ATA_CMD_PIO_WRITE:
 363         case ATA_CMD_PIO_WRITE_EXT:
 364                 put_lba(ah, f->lba);
 365
 366                 n = f->bcnt;
 367                 if (n > DEFAULTBCNT)
 368                         n = DEFAULTBCNT;
 369                 ah->scnt = n >> 9;
 370                 if (ah->aflags & AOEAFL_WRITE) {
 371                         skb_fill_page_desc(skb, 0, virt_to_page(f->bufaddr),
 372                                 offset_in_page(f->bufaddr), n);
 373                         skb->len = sizeof *h + sizeof *ah + n;
 374                         skb->data_len = n;
 375                 }
 376         }
 377         skb->dev = t->ifp->nd;
 378         skb = skb_clone(skb, GFP_ATOMIC);
 379         if (skb == NULL)
 380                 return;
 381         __skb_queue_tail(&d->sendq, skb);
 382 }
 383
 384 static int
 385 tsince(int tag)
 386 {
 387         int n;
 388
 389         n = jiffies & 0xffff;
 390         n -= tag & 0xffff;
 391         if (n < 0)
 392                 n += 1<<16;
 393         return n;
 394 }
 395
 396 static struct aoeif *
 397 getif(struct aoetgt *t, struct net_device *nd)
 398 {
 399         struct aoeif *p, *e;
 400
 401         p = t->ifs;
 402         e = p + NAOEIFS;
 403         for (; p < e; p++)
 404                 if (p->nd == nd)
 405                         return p;
 406         return NULL;
 407 }
 408
 409 static struct aoeif *
 410 addif(struct aoetgt *t, struct net_device *nd)
 411 {
 412         struct aoeif *p;
 413
 414         p = getif(t, NULL);
 415         if (!p)
 416                 return NULL;
 417         p->nd = nd;
 418         p->maxbcnt = DEFAULTBCNT;
 419         p->lost = 0;
 420         p->lostjumbo = 0;
 421         return p;
 422 }
 423
 424 static void
 425 ejectif(struct aoetgt *t, struct aoeif *ifp)
 426 {
 427         struct aoeif *e;
 428         ulong n;
 429
 430         e = t->ifs + NAOEIFS - 1;
 431         n = (e - ifp) * sizeof *ifp;
 432         memmove(ifp, ifp+1, n);
 433         e->nd = NULL;
 434 }
 435
 436 static int
 437 sthtith(struct aoedev *d)
 438 {
 439         struct frame *f, *e, *nf;
 440         struct sk_buff *skb;
 441         struct aoetgt *ht = *d->htgt;
 442
 443         f = ht->frames;
 444         e = f + ht->nframes;
 445         for (; f < e; f++) {
 446                 if (f->tag == FREETAG)
 447                         continue;
 448                 nf = freeframe(d);
 449                 if (!nf)
 450                         return 0;
 451                 skb = nf->skb;
 452                 *nf = *f;
 453                 f->skb = skb;
 454                 f->tag = FREETAG;
 455                 nf->waited = 0;
 456                 ht->nout--;
 457                 (*d->tgt)->nout++;
 458                 resend(d, *d->tgt, nf);
 459         }
 460         /* he's clean, he's useless.  take away his interfaces */
 461         memset(ht->ifs, 0, sizeof ht->ifs);
 462         d->htgt = NULL;
 463         return 1;
 464 }
 465
 466 static inline unsigned char
 467 ata_scnt(unsigned char *packet) {
 468         struct aoe_hdr *h;
 469         struct aoe_atahdr *ah;
 470
 471         h = (struct aoe_hdr *) packet;
 472         ah = (struct aoe_atahdr *) (h+1);
 473         return ah->scnt;
 474 }
 475
 476 static void
 477 rexmit_timer(ulong vp)
 478 {
 479         struct sk_buff_head queue;
 480         struct aoedev *d;
 481         struct aoetgt *t, **tt, **te;
 482         struct aoeif *ifp;
 483         struct frame *f, *e;
 484         register long timeout;
 485         ulong flags, n;
 486
 487         d = (struct aoedev *) vp;
 488
 489         /* timeout is always ~150% of the moving average */
 490         timeout = d->rttavg;
 491         timeout += timeout >> 1;
 492
 493         spin_lock_irqsave(&d->lock, flags);
 494
 495         if (d->flags & DEVFL_TKILL) {
 496                 spin_unlock_irqrestore(&d->lock, flags);
 497                 return;
 498         }
 499         tt = d->targets;
 500         te = tt + NTARGETS;
 501         for (; tt < te && *tt; tt++) {
 502                 t = *tt;
 503                 f = t->frames;
 504                 e = f + t->nframes;
 505                 for (; f < e; f++) {
 506                         if (f->tag == FREETAG
 507                         || tsince(f->tag) < timeout)
 508                                 continue;
 509                         n = f->waited += timeout;
 510                         n /= HZ;
 511                         if (n > aoe_deadsecs) {
 512                                 /* waited too long.  device failure. */
 513                                 aoedev_downdev(d);
 514                                 break;
 515                         }
 516
 517                         if (n > HELPWAIT /* see if another target can help */
 518                         && (tt != d->targets || d->targets[1]))
 519                                 d->htgt = tt;
 520
 521                         if (t->nout == t->maxout) {
 522                                 if (t->maxout > 1)
 523                                         t->maxout--;
 524                                 t->lastwadj = jiffies;
 525                         }
 526
 527                         ifp = getif(t, f->skb->dev);
 528                         if (ifp && ++ifp->lost > (t->nframes << 1)
 529                         && (ifp != t->ifs || t->ifs[1].nd)) {
 530                                 ejectif(t, ifp);
 531                                 ifp = NULL;
 532                         }
 533
 534                         if (ata_scnt(skb_mac_header(f->skb)) > DEFAULTBCNT / 512
 535                         && ifp && ++ifp->lostjumbo > (t->nframes << 1)
 536                         && ifp->maxbcnt != DEFAULTBCNT) {
 537                                 printk(KERN_INFO
 538                                         "aoe: e%ld.%d: "
 539                                         "too many lost jumbo on "
 540                                         "%s:%pm - "
 541                                         "falling back to %d frames.\n",
 542                                         d->aoemajor, d->aoeminor,
 543                                         ifp->nd->name, t->addr,
 544                                         DEFAULTBCNT);
 545                                 ifp->maxbcnt = 0;
 546                         }
 547                         resend(d, t, f);
 548                 }
 549
 550                 /* window check */
 551                 if (t->nout == t->maxout
 552                 && t->maxout < t->nframes
 553                 && (jiffies - t->lastwadj)/HZ > 10) {
 554                         t->maxout++;
 555                         t->lastwadj = jiffies;
 556                 }
 557         }
 558
 559         if (!skb_queue_empty(&d->sendq)) {
 560                 n = d->rttavg <<= 1;
 561                 if (n > MAXTIMER)
 562                         d->rttavg = MAXTIMER;
 563         }
 564
 565         if (d->flags & DEVFL_KICKME || d->htgt) {
 566                 d->flags &= ~DEVFL_KICKME;
 567                 aoecmd_work(d);
 568         }
 569
 570         __skb_queue_head_init(&queue);
 571         skb_queue_splice_init(&d->sendq, &queue);
 572
 573         d->timer.expires = jiffies + TIMERTICK;
 574         add_timer(&d->timer);
 575
 576         spin_unlock_irqrestore(&d->lock, flags);
 577
 578         aoenet_xmit(&queue);
 579 }
 580
 581 /* enters with d->lock held */
 582 void
 583 aoecmd_work(struct aoedev *d)
 584 {
 585         struct buf *buf;
 586 loop:
 587         if (d->htgt && !sthtith(d))
 588                 return;
 589         if (d->inprocess == NULL) {
 590                 if (list_empty(&d->bufq))
 591                         return;
 592                 buf = container_of(d->bufq.next, struct buf, bufs);
 593                 list_del(d->bufq.next);
 594                 d->inprocess = buf;
 595         }
 596         if (aoecmd_ata_rw(d))
 597                 goto loop;
 598 }
 599
 600 /* this function performs work that has been deferred until sleeping is OK
 601  */
 602 void
 603 aoecmd_sleepwork(struct work_struct *work)
 604 {
 605         struct aoedev *d = container_of(work, struct aoedev, work);
 606
 607         if (d->flags & DEVFL_GDALLOC)
 608                 aoeblk_gdalloc(d);
 609
 610         if (d->flags & DEVFL_NEWSIZE) {
 611                 struct block_device *bd;
 612                 unsigned long flags;
 613                 u64 ssize;
 614
 615                 ssize = get_capacity(d->gd);
 616                 bd = bdget_disk(d->gd, 0);
 617
 618                 if (bd) {
 619                         mutex_lock(&bd->bd_inode->i_mutex);
 620                         i_size_write(bd->bd_inode, (loff_t)ssize<<9);
 621                         mutex_unlock(&bd->bd_inode->i_mutex);
 622                         bdput(bd);
 623                 }
 624                 spin_lock_irqsave(&d->lock, flags);
 625                 d->flags |= DEVFL_UP;
 626                 d->flags &= ~DEVFL_NEWSIZE;
 627                 spin_unlock_irqrestore(&d->lock, flags);
 628         }
 629 }
 630
 631 static void
 632 ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
 633 {
 634         u64 ssize;
 635         u16 n;
 636
 637         /* word 83: command set supported */
 638         n = get_unaligned_le16(&id[83 << 1]);
 639
 640         /* word 86: command set/feature enabled */
 641         n |= get_unaligned_le16(&id[86 << 1]);
 642
 643         if (n & (1<<10)) {      /* bit 10: LBA 48 */
 644                 d->flags |= DEVFL_EXT;
 645
 646                 /* word 100: number lba48 sectors */
 647                 ssize = get_unaligned_le64(&id[100 << 1]);
 648
 649                 /* set as in ide-disk.c:init_idedisk_capacity */
 650                 d->geo.cylinders = ssize;
 651                 d->geo.cylinders /= (255 * 63);
 652                 d->geo.heads = 255;
 653                 d->geo.sectors = 63;
 654         } else {
 655                 d->flags &= ~DEVFL_EXT;
 656
 657                 /* number lba28 sectors */
 658                 ssize = get_unaligned_le32(&id[60 << 1]);
 659
 660                 /* NOTE: obsolete in ATA 6 */
 661                 d->geo.cylinders = get_unaligned_le16(&id[54 << 1]);
 662                 d->geo.heads = get_unaligned_le16(&id[55 << 1]);
 663                 d->geo.sectors = get_unaligned_le16(&id[56 << 1]);
 664         }
 665
 666         if (d->ssize != ssize)
 667                 printk(KERN_INFO
 668                         "aoe: %pm e%ld.%d v%04x has %llu sectors\n",
 669                         t->addr,
 670                         d->aoemajor, d->aoeminor,
 671                         d->fw_ver, (long long)ssize);
 672         d->ssize = ssize;
 673         d->geo.start = 0;
 674         if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
 675                 return;
 676         if (d->gd != NULL) {
 677                 set_capacity(d->gd, ssize);
 678                 d->flags |= DEVFL_NEWSIZE;
 679         } else
 680                 d->flags |= DEVFL_GDALLOC;
 681         schedule_work(&d->work);
 682 }
 683
 684 static void
 685 calc_rttavg(struct aoedev *d, int rtt)
 686 {
 687         register long n;
 688
 689         n = rtt;
 690         if (n < 0) {
 691                 n = -rtt;
 692                 if (n < MINTIMER)
 693                         n = MINTIMER;
 694                 else if (n > MAXTIMER)
 695                         n = MAXTIMER;
 696                 d->mintimer += (n - d->mintimer) >> 1;
 697         } else if (n < d->mintimer)
 698                 n = d->mintimer;
 699         else if (n > MAXTIMER)
 700                 n = MAXTIMER;
 701
 702         /* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
 703         n -= d->rttavg;
 704         d->rttavg += n >> 2;
 705 }
 706
 707 static struct aoetgt *
 708 gettgt(struct aoedev *d, char *addr)
 709 {
 710         struct aoetgt **t, **e;
 711
 712         t = d->targets;
 713         e = t + NTARGETS;
 714         for (; t < e && *t; t++)
 715                 if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0)
 716                         return *t;
 717         return NULL;
 718 }
 719
 720 static inline void
 721 diskstats(struct gendisk *disk, struct bio *bio, ulong duration, sector_t sector)
 722 {
 723         unsigned long n_sect = bio->bi_size >> 9;
 724         const int rw = bio_data_dir(bio);
 725         struct hd_struct *part;
 726         int cpu;
 727
 728         cpu = part_stat_lock();
 729         part = disk_map_sector_rcu(disk, sector);
 730
 731         part_stat_inc(cpu, part, ios[rw]);
 732         part_stat_add(cpu, part, ticks[rw], duration);
 733         part_stat_add(cpu, part, sectors[rw], n_sect);
 734         part_stat_add(cpu, part, io_ticks, duration);
 735
 736         part_stat_unlock();
 737 }
 738
 739 void
 740 aoecmd_ata_rsp(struct sk_buff *skb)
 741 {
 742         struct sk_buff_head queue;
 743         struct aoedev *d;
 744         struct aoe_hdr *hin, *hout;
 745         struct aoe_atahdr *ahin, *ahout;
 746         struct frame *f;
 747         struct buf *buf;
 748         struct aoetgt *t;
 749         struct aoeif *ifp;
 750         register long n;
 751         ulong flags;
 752         char ebuf[128];
 753         u16 aoemajor;
 754
 755         hin = (struct aoe_hdr *) skb_mac_header(skb);
 756         aoemajor = get_unaligned_be16(&hin->major);
 757         d = aoedev_by_aoeaddr(aoemajor, hin->minor);
 758         if (d == NULL) {
 759                 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
 760                         "for unknown device %d.%d\n",
 761                          aoemajor, hin->minor);
 762                 aoechr_error(ebuf);
 763                 return;
 764         }
 765
 766         spin_lock_irqsave(&d->lock, flags);
 767
 768         n = get_unaligned_be32(&hin->tag);
 769         t = gettgt(d, hin->src);
 770         if (t == NULL) {
 771                 printk(KERN_INFO "aoe: can't find target e%ld.%d:%pm\n",
 772                         d->aoemajor, d->aoeminor, hin->src);
 773                 spin_unlock_irqrestore(&d->lock, flags);
 774                 return;
 775         }
 776         f = getframe(t, n);
 777         if (f == NULL) {
 778                 calc_rttavg(d, -tsince(n));
 779                 spin_unlock_irqrestore(&d->lock, flags);
 780                 snprintf(ebuf, sizeof ebuf,
 781                         "%15s e%d.%d    tag=%08x@%08lx\n",
 782                         "unexpected rsp",
 783                         get_unaligned_be16(&hin->major),
 784                         hin->minor,
 785                         get_unaligned_be32(&hin->tag),
 786                         jiffies);
 787                 aoechr_error(ebuf);
 788                 return;
 789         }
 790
 791         calc_rttavg(d, tsince(f->tag));
 792
 793         ahin = (struct aoe_atahdr *) (hin+1);
 794         hout = (struct aoe_hdr *) skb_mac_header(f->skb);
 795         ahout = (struct aoe_atahdr *) (hout+1);
 796         buf = f->buf;
 797
 798         if (ahin->cmdstat & 0xa9) {     /* these bits cleared on success */
 799                 printk(KERN_ERR
 800                         "aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n",
 801                         ahout->cmdstat, ahin->cmdstat,
 802                         d->aoemajor, d->aoeminor);
 803                 if (buf)
 804                         buf->flags |= BUFFL_FAIL;
 805         } else {
 806                 if (d->htgt && t == *d->htgt) /* I'll help myself, thank you. */
 807                         d->htgt = NULL;
 808                 n = ahout->scnt << 9;
 809                 switch (ahout->cmdstat) {
 810                 case ATA_CMD_PIO_READ:
 811                 case ATA_CMD_PIO_READ_EXT:
 812                         if (skb->len - sizeof *hin - sizeof *ahin < n) {
 813                                 printk(KERN_ERR
 814                                         "aoe: %s.  skb->len=%d need=%ld\n",
 815                                         "runt data size in read", skb->len, n);
 816                                 /* fail frame f?  just returning will rexmit. */
 817                                 spin_unlock_irqrestore(&d->lock, flags);
 818                                 return;
 819                         }
 820                         memcpy(f->bufaddr, ahin+1, n);
 821                 case ATA_CMD_PIO_WRITE:
 822                 case ATA_CMD_PIO_WRITE_EXT:
 823                         ifp = getif(t, skb->dev);
 824                         if (ifp) {
 825                                 ifp->lost = 0;
 826                                 if (n > DEFAULTBCNT)
 827                                         ifp->lostjumbo = 0;
 828                         }
 829                         if (f->bcnt -= n) {
 830                                 f->lba += n >> 9;
 831                                 f->bufaddr += n;
 832                                 resend(d, t, f);
 833                                 goto xmit;
 834                         }
 835                         break;
 836                 case ATA_CMD_ID_ATA:
 837                         if (skb->len - sizeof *hin - sizeof *ahin < 512) {
 838                                 printk(KERN_INFO
 839                                         "aoe: runt data size in ataid.  skb->len=%d\n",
 840                                         skb->len);
 841                                 spin_unlock_irqrestore(&d->lock, flags);
 842                                 return;
 843                         }
 844                         ataid_complete(d, t, (char *) (ahin+1));
 845                         break;
 846                 default:
 847                         printk(KERN_INFO
 848                                 "aoe: unrecognized ata command %2.2Xh for %d.%d\n",
 849                                 ahout->cmdstat,
 850                                 get_unaligned_be16(&hin->major),
 851                                 hin->minor);
 852                 }
 853         }
 854
 855         if (buf && --buf->nframesout == 0 && buf->resid == 0) {
 856                 diskstats(d->gd, buf->bio, jiffies - buf->stime, buf->sector);
 857                 if (buf->flags & BUFFL_FAIL)
 858                         bio_endio(buf->bio, -EIO);
 859                 else {
 860                         bio_flush_dcache_pages(buf->bio);
 861                         bio_endio(buf->bio, 0);
 862                 }
 863                 mempool_free(buf, d->bufpool);
 864         }
 865
 866         f->buf = NULL;
 867         f->tag = FREETAG;
 868         t->nout--;
 869
 870         aoecmd_work(d);
 871 xmit:
 872         __skb_queue_head_init(&queue);
 873         skb_queue_splice_init(&d->sendq, &queue);
 874
 875         spin_unlock_irqrestore(&d->lock, flags);
 876         aoenet_xmit(&queue);
 877 }
 878
 879 void
 880 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
 881 {
 882         struct sk_buff_head queue;
 883
 884         __skb_queue_head_init(&queue);
 885         aoecmd_cfg_pkts(aoemajor, aoeminor, &queue);
 886         aoenet_xmit(&queue);
 887 }
 888
 889 struct sk_buff *
 890 aoecmd_ata_id(struct aoedev *d)
 891 {
 892         struct aoe_hdr *h;
 893         struct aoe_atahdr *ah;
 894         struct frame *f;
 895         struct sk_buff *skb;
 896         struct aoetgt *t;
 897
 898         f = freeframe(d);
 899         if (f == NULL)
 900                 return NULL;
 901
 902         t = *d->tgt;
 903
 904         /* initialize the headers & frame */
 905         skb = f->skb;
 906         h = (struct aoe_hdr *) skb_mac_header(skb);
 907         ah = (struct aoe_atahdr *) (h+1);
 908         skb_put(skb, sizeof *h + sizeof *ah);
 909         memset(h, 0, skb->len);
 910         f->tag = aoehdr_atainit(d, t, h);
 911         t->nout++;
 912         f->waited = 0;
 913
 914         /* set up ata header */
 915         ah->scnt = 1;
 916         ah->cmdstat = ATA_CMD_ID_ATA;
 917         ah->lba3 = 0xa0;
 918
 919         skb->dev = t->ifp->nd;
 920
 921         d->rttavg = MAXTIMER;
 922         d->timer.function = rexmit_timer;
 923
 924         return skb_clone(skb, GFP_ATOMIC);
 925 }
 926
 927 static struct aoetgt *
 928 addtgt(struct aoedev *d, char *addr, ulong nframes)
 929 {
 930         struct aoetgt *t, **tt, **te;
 931         struct frame *f, *e;
 932
 933         tt = d->targets;
 934         te = tt + NTARGETS;
 935         for (; tt < te && *tt; tt++)
 936                 ;
 937
 938         if (tt == te) {
 939                 printk(KERN_INFO
 940                         "aoe: device addtgt failure; too many targets\n");
 941                 return NULL;
 942         }
 943         t = kcalloc(1, sizeof *t, GFP_ATOMIC);
 944         f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
 945         if (!t || !f) {
 946                 kfree(f);
 947                 kfree(t);
 948                 printk(KERN_INFO "aoe: cannot allocate memory to add target\n");
 949                 return NULL;
 950         }
 951
 952         t->nframes = nframes;
 953         t->frames = f;
 954         e = f + nframes;
 955         for (; f < e; f++)
 956                 f->tag = FREETAG;
 957         memcpy(t->addr, addr, sizeof t->addr);
 958         t->ifp = t->ifs;
 959         t->maxout = t->nframes;
 960         return *tt = t;
 961 }
 962
 963 void
 964 aoecmd_cfg_rsp(struct sk_buff *skb)
 965 {
 966         struct aoedev *d;
 967         struct aoe_hdr *h;
 968         struct aoe_cfghdr *ch;
 969         struct aoetgt *t;
 970         struct aoeif *ifp;
 971         ulong flags, sysminor, aoemajor;
 972         struct sk_buff *sl;
 973         u16 n;
 974
 975         h = (struct aoe_hdr *) skb_mac_header(skb);
 976         ch = (struct aoe_cfghdr *) (h+1);
 977
 978         /*
 979          * Enough people have their dip switches set backwards to
 980          * warrant a loud message for this special case.
 981          */
 982         aoemajor = get_unaligned_be16(&h->major);
 983         if (aoemajor == 0xfff) {
 984                 printk(KERN_ERR "aoe: Warning: shelf address is all ones.  "
 985                         "Check shelf dip switches.\n");
 986                 return;
 987         }
 988
 989         sysminor = SYSMINOR(aoemajor, h->minor);
 990         if (sysminor * AOE_PARTITIONS + AOE_PARTITIONS > MINORMASK) {
 991                 printk(KERN_INFO "aoe: e%ld.%d: minor number too large\n",
 992                         aoemajor, (int) h->minor);
 993                 return;
 994         }
 995
 996         n = be16_to_cpu(ch->bufcnt);
 997         if (n > aoe_maxout)     /* keep it reasonable */
 998                 n = aoe_maxout;
 999
1000         d = aoedev_by_sysminor_m(sysminor);
1001         if (d == NULL) {
1002                 printk(KERN_INFO "aoe: device sysminor_m failure\n");
1003                 return;
1004         }
1005
1006         spin_lock_irqsave(&d->lock, flags);
1007
1008         t = gettgt(d, h->src);
1009         if (!t) {
1010                 t = addtgt(d, h->src, n);
1011                 if (!t) {
1012                         spin_unlock_irqrestore(&d->lock, flags);
1013                         return;
1014                 }
1015         }
1016         ifp = getif(t, skb->dev);
1017         if (!ifp) {
1018                 ifp = addif(t, skb->dev);
1019                 if (!ifp) {
1020                         printk(KERN_INFO
1021                                 "aoe: device addif failure; "
1022                                 "too many interfaces?\n");
1023                         spin_unlock_irqrestore(&d->lock, flags);
1024                         return;
1025                 }
1026         }
1027         if (ifp->maxbcnt) {
1028                 n = ifp->nd->mtu;
1029                 n -= sizeof (struct aoe_hdr) + sizeof (struct aoe_atahdr);
1030                 n /= 512;
1031                 if (n > ch->scnt)
1032                         n = ch->scnt;
1033                 n = n ? n * 512 : DEFAULTBCNT;
1034                 if (n != ifp->maxbcnt) {
1035                         printk(KERN_INFO
1036                                 "aoe: e%ld.%d: setting %d%s%s:%pm\n",
1037                                 d->aoemajor, d->aoeminor, n,
1038                                 " byte data frames on ", ifp->nd->name,
1039                                 t->addr);
1040                         ifp->maxbcnt = n;
1041                 }
1042         }
1043
1044         /* don't change users' perspective */
1045         if (d->nopen) {
1046                 spin_unlock_irqrestore(&d->lock, flags);
1047                 return;
1048         }
1049         d->fw_ver = be16_to_cpu(ch->fwver);
1050
1051         sl = aoecmd_ata_id(d);
1052
1053         spin_unlock_irqrestore(&d->lock, flags);
1054
1055         if (sl) {
1056                 struct sk_buff_head queue;
1057                 __skb_queue_head_init(&queue);
1058                 __skb_queue_tail(&queue, sl);
1059                 aoenet_xmit(&queue);
1060         }
1061 }
1062
1063 void
1064 aoecmd_cleanslate(struct aoedev *d)
1065 {
1066         struct aoetgt **t, **te;
1067         struct aoeif *p, *e;
1068
1069         d->mintimer = MINTIMER;
1070
1071         t = d->targets;
1072         te = t + NTARGETS;
1073         for (; t < te && *t; t++) {
1074                 (*t)->maxout = (*t)->nframes;
1075                 p = (*t)->ifs;
1076                 e = p + NAOEIFS;
1077                 for (; p < e; p++) {
1078                         p->lostjumbo = 0;
1079                         p->lost = 0;
1080                         p->maxbcnt = DEFAULTBCNT;
1081                 }
1082         }
1083 }