drivers/block/aoe/aoecmd.c

   1 /* Copyright (c) 2004 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 "aoe.h"
  12
  13 #define TIMERTICK (HZ / 10)
  14 #define MINTIMER (2 * TIMERTICK)
  15 #define MAXTIMER (HZ << 1)
  16 #define MAXWAIT (60 * 3)        /* After MAXWAIT seconds, give up and fail dev */
  17
  18 static struct sk_buff *
  19 new_skb(struct net_device *if_dev, ulong len)
  20 {
  21         struct sk_buff *skb;
  22
  23         skb = alloc_skb(len, GFP_ATOMIC);
  24         if (skb) {
  25                 skb->nh.raw = skb->mac.raw = skb->data;
  26                 skb->dev = if_dev;
  27                 skb->protocol = __constant_htons(ETH_P_AOE);
  28                 skb->priority = 0;
  29                 skb_put(skb, len);
  30                 skb->next = skb->prev = NULL;
  31
  32                 /* tell the network layer not to perform IP checksums
  33                  * or to get the NIC to do it
  34                  */
  35                 skb->ip_summed = CHECKSUM_NONE;
  36         }
  37         return skb;
  38 }
  39
  40 static struct sk_buff *
  41 skb_prepare(struct aoedev *d, struct frame *f)
  42 {
  43         struct sk_buff *skb;
  44         char *p;
  45
  46         skb = new_skb(d->ifp, f->ndata + f->writedatalen);
  47         if (!skb) {
  48                 printk(KERN_INFO "aoe: skb_prepare: failure to allocate skb\n");
  49                 return NULL;
  50         }
  51
  52         p = skb->mac.raw;
  53         memcpy(p, f->data, f->ndata);
  54
  55         if (f->writedatalen) {
  56                 p += sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr);
  57                 memcpy(p, f->bufaddr, f->writedatalen);
  58         }
  59
  60         return skb;
  61 }
  62
  63 static struct frame *
  64 getframe(struct aoedev *d, int tag)
  65 {
  66         struct frame *f, *e;
  67
  68         f = d->frames;
  69         e = f + d->nframes;
  70         for (; f<e; f++)
  71                 if (f->tag == tag)
  72                         return f;
  73         return NULL;
  74 }
  75
  76 /*
  77  * Leave the top bit clear so we have tagspace for userland.
  78  * The bottom 16 bits are the xmit tick for rexmit/rttavg processing.
  79  * This driver reserves tag -1 to mean "unused frame."
  80  */
  81 static int
  82 newtag(struct aoedev *d)
  83 {
  84         register ulong n;
  85
  86         n = jiffies & 0xffff;
  87         return n |= (++d->lasttag & 0x7fff) << 16;
  88 }
  89
  90 static int
  91 aoehdr_atainit(struct aoedev *d, struct aoe_hdr *h)
  92 {
  93         u16 type = __constant_cpu_to_be16(ETH_P_AOE);
  94         u16 aoemajor = __cpu_to_be16(d->aoemajor);
  95         u32 host_tag = newtag(d);
  96         u32 tag = __cpu_to_be32(host_tag);
  97
  98         memcpy(h->src, d->ifp->dev_addr, sizeof h->src);
  99         memcpy(h->dst, d->addr, sizeof h->dst);
 100         memcpy(h->type, &type, sizeof type);
 101         h->verfl = AOE_HVER;
 102         memcpy(h->major, &aoemajor, sizeof aoemajor);
 103         h->minor = d->aoeminor;
 104         h->cmd = AOECMD_ATA;
 105         memcpy(h->tag, &tag, sizeof tag);
 106
 107         return host_tag;
 108 }
 109
 110 static void
 111 aoecmd_ata_rw(struct aoedev *d, struct frame *f)
 112 {
 113         struct aoe_hdr *h;
 114         struct aoe_atahdr *ah;
 115         struct buf *buf;
 116         struct sk_buff *skb;
 117         ulong bcnt;
 118         register sector_t sector;
 119         char writebit, extbit;
 120
 121         writebit = 0x10;
 122         extbit = 0x4;
 123
 124         buf = d->inprocess;
 125
 126         sector = buf->sector;
 127         bcnt = buf->bv_resid;
 128         if (bcnt > MAXATADATA)
 129                 bcnt = MAXATADATA;
 130
 131         /* initialize the headers & frame */
 132         h = (struct aoe_hdr *) f->data;
 133         ah = (struct aoe_atahdr *) (h+1);
 134         f->ndata = sizeof *h + sizeof *ah;
 135         memset(h, 0, f->ndata);
 136         f->tag = aoehdr_atainit(d, h);
 137         f->waited = 0;
 138         f->buf = buf;
 139         f->bufaddr = buf->bufaddr;
 140
 141         /* set up ata header */
 142         ah->scnt = bcnt >> 9;
 143         ah->lba0 = sector;
 144         ah->lba1 = sector >>= 8;
 145         ah->lba2 = sector >>= 8;
 146         ah->lba3 = sector >>= 8;
 147         if (d->flags & DEVFL_EXT) {
 148                 ah->aflags |= AOEAFL_EXT;
 149                 ah->lba4 = sector >>= 8;
 150                 ah->lba5 = sector >>= 8;
 151         } else {
 152                 extbit = 0;
 153                 ah->lba3 &= 0x0f;
 154                 ah->lba3 |= 0xe0;       /* LBA bit + obsolete 0xa0 */
 155         }
 156
 157         if (bio_data_dir(buf->bio) == WRITE) {
 158                 ah->aflags |= AOEAFL_WRITE;
 159                 f->writedatalen = bcnt;
 160         } else {
 161                 writebit = 0;
 162                 f->writedatalen = 0;
 163         }
 164
 165         ah->cmdstat = WIN_READ | writebit | extbit;
 166
 167         /* mark all tracking fields and load out */
 168         buf->nframesout += 1;
 169         buf->bufaddr += bcnt;
 170         buf->bv_resid -= bcnt;
 171 /* printk(KERN_INFO "aoe: bv_resid=%ld\n", buf->bv_resid); */
 172         buf->resid -= bcnt;
 173         buf->sector += bcnt >> 9;
 174         if (buf->resid == 0) {
 175                 d->inprocess = NULL;
 176         } else if (buf->bv_resid == 0) {
 177                 buf->bv++;
 178                 buf->bv_resid = buf->bv->bv_len;
 179                 buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
 180         }
 181
 182         skb = skb_prepare(d, f);
 183         if (skb) {
 184                 skb->next = d->skblist;
 185                 d->skblist = skb;
 186         }
 187 }
 188
 189 /* enters with d->lock held */
 190 void
 191 aoecmd_work(struct aoedev *d)
 192 {
 193         struct frame *f;
 194         struct buf *buf;
 195 loop:
 196         f = getframe(d, FREETAG);
 197         if (f == NULL)
 198                 return;
 199         if (d->inprocess == NULL) {
 200                 if (list_empty(&d->bufq))
 201                         return;
 202                 buf = container_of(d->bufq.next, struct buf, bufs);
 203                 list_del(d->bufq.next);
 204 /*printk(KERN_INFO "aoecmd_work: bi_size=%ld\n", buf->bio->bi_size); */
 205                 d->inprocess = buf;
 206         }
 207         aoecmd_ata_rw(d, f);
 208         goto loop;
 209 }
 210
 211 static void
 212 rexmit(struct aoedev *d, struct frame *f)
 213 {
 214         struct sk_buff *skb;
 215         struct aoe_hdr *h;
 216         char buf[128];
 217         u32 n;
 218         u32 net_tag;
 219
 220         n = newtag(d);
 221
 222         snprintf(buf, sizeof buf,
 223                 "%15s e%ld.%ld oldtag=%08x@%08lx newtag=%08x\n",
 224                 "retransmit",
 225                 d->aoemajor, d->aoeminor, f->tag, jiffies, n);
 226         aoechr_error(buf);
 227
 228         h = (struct aoe_hdr *) f->data;
 229         f->tag = n;
 230         net_tag = __cpu_to_be32(n);
 231         memcpy(h->tag, &net_tag, sizeof net_tag);
 232
 233         skb = skb_prepare(d, f);
 234         if (skb) {
 235                 skb->next = d->skblist;
 236                 d->skblist = skb;
 237         }
 238 }
 239
 240 static int
 241 tsince(int tag)
 242 {
 243         int n;
 244
 245         n = jiffies & 0xffff;
 246         n -= tag & 0xffff;
 247         if (n < 0)
 248                 n += 1<<16;
 249         return n;
 250 }
 251
 252 static void
 253 rexmit_timer(ulong vp)
 254 {
 255         struct aoedev *d;
 256         struct frame *f, *e;
 257         struct sk_buff *sl;
 258         register long timeout;
 259         ulong flags, n;
 260
 261         d = (struct aoedev *) vp;
 262         sl = NULL;
 263
 264         /* timeout is always ~150% of the moving average */
 265         timeout = d->rttavg;
 266         timeout += timeout >> 1;
 267
 268         spin_lock_irqsave(&d->lock, flags);
 269
 270         if (d->flags & DEVFL_TKILL) {
 271 tdie:           spin_unlock_irqrestore(&d->lock, flags);
 272                 return;
 273         }
 274         f = d->frames;
 275         e = f + d->nframes;
 276         for (; f<e; f++) {
 277                 if (f->tag != FREETAG && tsince(f->tag) >= timeout) {
 278                         n = f->waited += timeout;
 279                         n /= HZ;
 280                         if (n > MAXWAIT) { /* waited too long.  device failure. */
 281                                 aoedev_downdev(d);
 282                                 goto tdie;
 283                         }
 284                         rexmit(d, f);
 285                 }
 286         }
 287
 288         sl = d->skblist;
 289         d->skblist = NULL;
 290         if (sl) {
 291                 n = d->rttavg <<= 1;
 292                 if (n > MAXTIMER)
 293                         d->rttavg = MAXTIMER;
 294         }
 295
 296         d->timer.expires = jiffies + TIMERTICK;
 297         add_timer(&d->timer);
 298
 299         spin_unlock_irqrestore(&d->lock, flags);
 300
 301         aoenet_xmit(sl);
 302 }
 303
 304 static void
 305 ataid_complete(struct aoedev *d, unsigned char *id)
 306 {
 307         u64 ssize;
 308         u16 n;
 309
 310         /* word 83: command set supported */
 311         n = __le16_to_cpu(*((u16 *) &id[83<<1]));
 312
 313         /* word 86: command set/feature enabled */
 314         n |= __le16_to_cpu(*((u16 *) &id[86<<1]));
 315
 316         if (n & (1<<10)) {      /* bit 10: LBA 48 */
 317                 d->flags |= DEVFL_EXT;
 318
 319                 /* word 100: number lba48 sectors */
 320                 ssize = __le64_to_cpu(*((u64 *) &id[100<<1]));
 321
 322                 /* set as in ide-disk.c:init_idedisk_capacity */
 323                 d->geo.cylinders = ssize;
 324                 d->geo.cylinders /= (255 * 63);
 325                 d->geo.heads = 255;
 326                 d->geo.sectors = 63;
 327         } else {
 328                 d->flags &= ~DEVFL_EXT;
 329
 330                 /* number lba28 sectors */
 331                 ssize = __le32_to_cpu(*((u32 *) &id[60<<1]));
 332
 333                 /* NOTE: obsolete in ATA 6 */
 334                 d->geo.cylinders = __le16_to_cpu(*((u16 *) &id[54<<1]));
 335                 d->geo.heads = __le16_to_cpu(*((u16 *) &id[55<<1]));
 336                 d->geo.sectors = __le16_to_cpu(*((u16 *) &id[56<<1]));
 337         }
 338         d->ssize = ssize;
 339         d->geo.start = 0;
 340         if (d->gd != NULL) {
 341                 d->gd->capacity = ssize;
 342                 d->flags |= DEVFL_UP;
 343                 return;
 344         }
 345         if (d->flags & DEVFL_WORKON) {
 346                 printk(KERN_INFO "aoe: ataid_complete: can't schedule work, it's already on!  "
 347                         "(This really shouldn't happen).\n");
 348                 return;
 349         }
 350         INIT_WORK(&d->work, aoeblk_gdalloc, d);
 351         schedule_work(&d->work);
 352         d->flags |= DEVFL_WORKON;
 353 }
 354
 355 static void
 356 calc_rttavg(struct aoedev *d, int rtt)
 357 {
 358         register long n;
 359
 360         n = rtt;
 361         if (n < MINTIMER)
 362                 n = MINTIMER;
 363         else if (n > MAXTIMER)
 364                 n = MAXTIMER;
 365
 366         /* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
 367         n -= d->rttavg;
 368         d->rttavg += n >> 2;
 369 }
 370
 371 void
 372 aoecmd_ata_rsp(struct sk_buff *skb)
 373 {
 374         struct aoedev *d;
 375         struct aoe_hdr *hin;
 376         struct aoe_atahdr *ahin, *ahout;
 377         struct frame *f;
 378         struct buf *buf;
 379         struct sk_buff *sl;
 380         register long n;
 381         ulong flags;
 382         char ebuf[128];
 383
 384         hin = (struct aoe_hdr *) skb->mac.raw;
 385         d = aoedev_bymac(hin->src);
 386         if (d == NULL) {
 387                 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
 388                         "for unknown device %d.%d\n",
 389                          __be16_to_cpu(*((u16 *) hin->major)),
 390                         hin->minor);
 391                 aoechr_error(ebuf);
 392                 return;
 393         }
 394
 395         spin_lock_irqsave(&d->lock, flags);
 396
 397         f = getframe(d, __be32_to_cpu(*((u32 *) hin->tag)));
 398         if (f == NULL) {
 399                 spin_unlock_irqrestore(&d->lock, flags);
 400                 snprintf(ebuf, sizeof ebuf,
 401                         "%15s e%d.%d    tag=%08x@%08lx\n",
 402                         "unexpected rsp",
 403                         __be16_to_cpu(*((u16 *) hin->major)),
 404                         hin->minor,
 405                         __be32_to_cpu(*((u32 *) hin->tag)),
 406                         jiffies);
 407                 aoechr_error(ebuf);
 408                 return;
 409         }
 410
 411         calc_rttavg(d, tsince(f->tag));
 412
 413         ahin = (struct aoe_atahdr *) (hin+1);
 414         ahout = (struct aoe_atahdr *) (f->data + sizeof(struct aoe_hdr));
 415         buf = f->buf;
 416
 417         if (ahin->cmdstat & 0xa9) {     /* these bits cleared on success */
 418                 printk(KERN_CRIT "aoe: aoecmd_ata_rsp: ata error cmd=%2.2Xh "
 419                         "stat=%2.2Xh from e%ld.%ld\n",
 420                         ahout->cmdstat, ahin->cmdstat,
 421                         d->aoemajor, d->aoeminor);
 422                 if (buf)
 423                         buf->flags |= BUFFL_FAIL;
 424         } else {
 425                 switch (ahout->cmdstat) {
 426                 case WIN_READ:
 427                 case WIN_READ_EXT:
 428                         n = ahout->scnt << 9;
 429                         if (skb->len - sizeof *hin - sizeof *ahin < n) {
 430                                 printk(KERN_CRIT "aoe: aoecmd_ata_rsp: runt "
 431                                         "ata data size in read.  skb->len=%d\n",
 432                                         skb->len);
 433                                 /* fail frame f?  just returning will rexmit. */
 434                                 spin_unlock_irqrestore(&d->lock, flags);
 435                                 return;
 436                         }
 437                         memcpy(f->bufaddr, ahin+1, n);
 438                 case WIN_WRITE:
 439                 case WIN_WRITE_EXT:
 440                         break;
 441                 case WIN_IDENTIFY:
 442                         if (skb->len - sizeof *hin - sizeof *ahin < 512) {
 443                                 printk(KERN_INFO "aoe: aoecmd_ata_rsp: runt data size "
 444                                         "in ataid.  skb->len=%d\n", skb->len);
 445                                 spin_unlock_irqrestore(&d->lock, flags);
 446                                 return;
 447                         }
 448                         ataid_complete(d, (char *) (ahin+1));
 449                         /* d->flags |= DEVFL_WC_UPDATE; */
 450                         break;
 451                 default:
 452                         printk(KERN_INFO "aoe: aoecmd_ata_rsp: unrecognized "
 453                                "outbound ata command %2.2Xh for %d.%d\n",
 454                                ahout->cmdstat,
 455                                __be16_to_cpu(*((u16 *) hin->major)),
 456                                hin->minor);
 457                 }
 458         }
 459
 460         if (buf) {
 461                 buf->nframesout -= 1;
 462                 if (buf->nframesout == 0 && buf->resid == 0) {
 463                         n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
 464                         bio_endio(buf->bio, buf->bio->bi_size, n);
 465                         mempool_free(buf, d->bufpool);
 466                 }
 467         }
 468
 469         f->buf = NULL;
 470         f->tag = FREETAG;
 471
 472         aoecmd_work(d);
 473
 474         sl = d->skblist;
 475         d->skblist = NULL;
 476
 477         spin_unlock_irqrestore(&d->lock, flags);
 478
 479         aoenet_xmit(sl);
 480 }
 481
 482 void
 483 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
 484 {
 485         struct aoe_hdr *h;
 486         struct aoe_cfghdr *ch;
 487         struct sk_buff *skb, *sl;
 488         struct net_device *ifp;
 489         u16 aoe_type = __constant_cpu_to_be16(ETH_P_AOE);
 490         u16 net_aoemajor = __cpu_to_be16(aoemajor);
 491
 492         sl = NULL;
 493
 494         read_lock(&dev_base_lock);
 495         for (ifp = dev_base; ifp; dev_put(ifp), ifp = ifp->next) {
 496                 dev_hold(ifp);
 497                 if (!is_aoe_netif(ifp))
 498                         continue;
 499
 500                 skb = new_skb(ifp, sizeof *h + sizeof *ch);
 501                 if (skb == NULL) {
 502                         printk(KERN_INFO "aoe: aoecmd_cfg: skb alloc failure\n");
 503                         continue;
 504                 }
 505                 h = (struct aoe_hdr *) skb->mac.raw;
 506                 memset(h, 0, sizeof *h + sizeof *ch);
 507
 508                 memset(h->dst, 0xff, sizeof h->dst);
 509                 memcpy(h->src, ifp->dev_addr, sizeof h->src);
 510                 memcpy(h->type, &aoe_type, sizeof aoe_type);
 511                 h->verfl = AOE_HVER;
 512                 memcpy(h->major, &net_aoemajor, sizeof net_aoemajor);
 513                 h->minor = aoeminor;
 514                 h->cmd = AOECMD_CFG;
 515
 516                 skb->next = sl;
 517                 sl = skb;
 518         }
 519         read_unlock(&dev_base_lock);
 520
 521         aoenet_xmit(sl);
 522 }
 523
 524 /*
 525  * Since we only call this in one place (and it only prepares one frame)
 526  * we just return the skb.  Usually we'd chain it up to the d->skblist.
 527  */
 528 static struct sk_buff *
 529 aoecmd_ata_id(struct aoedev *d)
 530 {
 531         struct aoe_hdr *h;
 532         struct aoe_atahdr *ah;
 533         struct frame *f;
 534         struct sk_buff *skb;
 535
 536         f = getframe(d, FREETAG);
 537         if (f == NULL) {
 538                 printk(KERN_CRIT "aoe: aoecmd_ata_id: can't get a frame.  "
 539                         "This shouldn't happen.\n");
 540                 return NULL;
 541         }
 542
 543         /* initialize the headers & frame */
 544         h = (struct aoe_hdr *) f->data;
 545         ah = (struct aoe_atahdr *) (h+1);
 546         f->ndata = sizeof *h + sizeof *ah;
 547         memset(h, 0, f->ndata);
 548         f->tag = aoehdr_atainit(d, h);
 549         f->waited = 0;
 550         f->writedatalen = 0;
 551
 552         /* this message initializes the device, so we reset the rttavg */
 553         d->rttavg = MAXTIMER;
 554
 555         /* set up ata header */
 556         ah->scnt = 1;
 557         ah->cmdstat = WIN_IDENTIFY;
 558         ah->lba3 = 0xa0;
 559
 560         skb = skb_prepare(d, f);
 561
 562         /* we now want to start the rexmit tracking */
 563         d->flags &= ~DEVFL_TKILL;
 564         d->timer.data = (ulong) d;
 565         d->timer.function = rexmit_timer;
 566         d->timer.expires = jiffies + TIMERTICK;
 567         add_timer(&d->timer);
 568
 569         return skb;
 570 }
 571
 572 void
 573 aoecmd_cfg_rsp(struct sk_buff *skb)
 574 {
 575         struct aoedev *d;
 576         struct aoe_hdr *h;
 577         struct aoe_cfghdr *ch;
 578         ulong flags, bufcnt, sysminor, aoemajor;
 579         struct sk_buff *sl;
 580         enum { MAXFRAMES = 8, MAXSYSMINOR = 255 };
 581
 582         h = (struct aoe_hdr *) skb->mac.raw;
 583         ch = (struct aoe_cfghdr *) (h+1);
 584
 585         /*
 586          * Enough people have their dip switches set backwards to
 587          * warrant a loud message for this special case.
 588          */
 589         aoemajor = __be16_to_cpu(*((u16 *) h->major));
 590         if (aoemajor == 0xfff) {
 591                 printk(KERN_CRIT "aoe: aoecmd_cfg_rsp: Warning: shelf "
 592                         "address is all ones.  Check shelf dip switches\n");
 593                 return;
 594         }
 595
 596         sysminor = SYSMINOR(aoemajor, h->minor);
 597         if (sysminor > MAXSYSMINOR) {
 598                 printk(KERN_INFO "aoe: aoecmd_cfg_rsp: sysminor %ld too "
 599                         "large\n", sysminor);
 600                 return;
 601         }
 602
 603         bufcnt = __be16_to_cpu(*((u16 *) ch->bufcnt));
 604         if (bufcnt > MAXFRAMES) /* keep it reasonable */
 605                 bufcnt = MAXFRAMES;
 606
 607         d = aoedev_set(sysminor, h->src, skb->dev, bufcnt);
 608         if (d == NULL) {
 609                 printk(KERN_INFO "aoe: aoecmd_cfg_rsp: device set failure\n");
 610                 return;
 611         }
 612
 613         spin_lock_irqsave(&d->lock, flags);
 614
 615         if (d->flags & (DEVFL_UP | DEVFL_CLOSEWAIT)) {
 616                 spin_unlock_irqrestore(&d->lock, flags);
 617                 return;
 618         }
 619
 620         d->fw_ver = __be16_to_cpu(*((u16 *) ch->fwver));
 621
 622         /* we get here only if the device is new */
 623         sl = aoecmd_ata_id(d);
 624
 625         spin_unlock_irqrestore(&d->lock, flags);
 626
 627         aoenet_xmit(sl);
 628 }
 629