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