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         u32 host_tag = newtag(d);
  94
  95         memcpy(h->src, d->ifp->dev_addr, sizeof h->src);
  96         memcpy(h->dst, d->addr, sizeof h->dst);
  97         h->type = __constant_cpu_to_be16(ETH_P_AOE);
  98         h->verfl = AOE_HVER;
  99         h->major = cpu_to_be16(d->aoemajor);
 100         h->minor = d->aoeminor;
 101         h->cmd = AOECMD_ATA;
 102         h->tag = cpu_to_be32(host_tag);
 103
 104         return host_tag;
 105 }
 106
 107 static void
 108 aoecmd_ata_rw(struct aoedev *d, struct frame *f)
 109 {
 110         struct aoe_hdr *h;
 111         struct aoe_atahdr *ah;
 112         struct buf *buf;
 113         struct sk_buff *skb;
 114         ulong bcnt;
 115         register sector_t sector;
 116         char writebit, extbit;
 117
 118         writebit = 0x10;
 119         extbit = 0x4;
 120
 121         buf = d->inprocess;
 122
 123         sector = buf->sector;
 124         bcnt = buf->bv_resid;
 125         if (bcnt > MAXATADATA)
 126                 bcnt = MAXATADATA;
 127
 128         /* initialize the headers & frame */
 129         h = (struct aoe_hdr *) f->data;
 130         ah = (struct aoe_atahdr *) (h+1);
 131         f->ndata = sizeof *h + sizeof *ah;
 132         memset(h, 0, f->ndata);
 133         f->tag = aoehdr_atainit(d, h);
 134         f->waited = 0;
 135         f->buf = buf;
 136         f->bufaddr = buf->bufaddr;
 137
 138         /* set up ata header */
 139         ah->scnt = bcnt >> 9;
 140         ah->lba0 = sector;
 141         ah->lba1 = sector >>= 8;
 142         ah->lba2 = sector >>= 8;
 143         ah->lba3 = sector >>= 8;
 144         if (d->flags & DEVFL_EXT) {
 145                 ah->aflags |= AOEAFL_EXT;
 146                 ah->lba4 = sector >>= 8;
 147                 ah->lba5 = sector >>= 8;
 148         } else {
 149                 extbit = 0;
 150                 ah->lba3 &= 0x0f;
 151                 ah->lba3 |= 0xe0;       /* LBA bit + obsolete 0xa0 */
 152         }
 153
 154         if (bio_data_dir(buf->bio) == WRITE) {
 155                 ah->aflags |= AOEAFL_WRITE;
 156                 f->writedatalen = bcnt;
 157         } else {
 158                 writebit = 0;
 159                 f->writedatalen = 0;
 160         }
 161
 162         ah->cmdstat = WIN_READ | writebit | extbit;
 163
 164         /* mark all tracking fields and load out */
 165         buf->nframesout += 1;
 166         buf->bufaddr += bcnt;
 167         buf->bv_resid -= bcnt;
 168 /* printk(KERN_INFO "aoe: bv_resid=%ld\n", buf->bv_resid); */
 169         buf->resid -= bcnt;
 170         buf->sector += bcnt >> 9;
 171         if (buf->resid == 0) {
 172                 d->inprocess = NULL;
 173         } else if (buf->bv_resid == 0) {
 174                 buf->bv++;
 175                 buf->bv_resid = buf->bv->bv_len;
 176                 buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
 177         }
 178
 179         skb = skb_prepare(d, f);
 180         if (skb) {
 181                 skb->next = NULL;
 182                 if (d->sendq_hd)
 183                         d->sendq_tl->next = skb;
 184                 else
 185                         d->sendq_hd = skb;
 186                 d->sendq_tl = skb;
 187         }
 188 }
 189
 190 /* enters with d->lock held */
 191 void
 192 aoecmd_work(struct aoedev *d)
 193 {
 194         struct frame *f;
 195         struct buf *buf;
 196 loop:
 197         f = getframe(d, FREETAG);
 198         if (f == NULL)
 199                 return;
 200         if (d->inprocess == NULL) {
 201                 if (list_empty(&d->bufq))
 202                         return;
 203                 buf = container_of(d->bufq.next, struct buf, bufs);
 204                 list_del(d->bufq.next);
 205 /*printk(KERN_INFO "aoecmd_work: bi_size=%ld\n", buf->bio->bi_size); */
 206                 d->inprocess = buf;
 207         }
 208         aoecmd_ata_rw(d, f);
 209         goto loop;
 210 }
 211
 212 static void
 213 rexmit(struct aoedev *d, struct frame *f)
 214 {
 215         struct sk_buff *skb;
 216         struct aoe_hdr *h;
 217         char buf[128];
 218         u32 n;
 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         h->tag = cpu_to_be32(n);
 231
 232         skb = skb_prepare(d, f);
 233         if (skb) {
 234                 skb->next = NULL;
 235                 if (d->sendq_hd)
 236                         d->sendq_tl->next = skb;
 237                 else
 238                         d->sendq_hd = skb;
 239                 d->sendq_tl = skb;
 240         }
 241 }
 242
 243 static int
 244 tsince(int tag)
 245 {
 246         int n;
 247
 248         n = jiffies & 0xffff;
 249         n -= tag & 0xffff;
 250         if (n < 0)
 251                 n += 1<<16;
 252         return n;
 253 }
 254
 255 static void
 256 rexmit_timer(ulong vp)
 257 {
 258         struct aoedev *d;
 259         struct frame *f, *e;
 260         struct sk_buff *sl;
 261         register long timeout;
 262         ulong flags, n;
 263
 264         d = (struct aoedev *) vp;
 265         sl = NULL;
 266
 267         /* timeout is always ~150% of the moving average */
 268         timeout = d->rttavg;
 269         timeout += timeout >> 1;
 270
 271         spin_lock_irqsave(&d->lock, flags);
 272
 273         if (d->flags & DEVFL_TKILL) {
 274 tdie:           spin_unlock_irqrestore(&d->lock, flags);
 275                 return;
 276         }
 277         f = d->frames;
 278         e = f + d->nframes;
 279         for (; f<e; f++) {
 280                 if (f->tag != FREETAG && tsince(f->tag) >= timeout) {
 281                         n = f->waited += timeout;
 282                         n /= HZ;
 283                         if (n > MAXWAIT) { /* waited too long.  device failure. */
 284                                 aoedev_downdev(d);
 285                                 goto tdie;
 286                         }
 287                         rexmit(d, f);
 288                 }
 289         }
 290
 291         sl = d->sendq_hd;
 292         d->sendq_hd = d->sendq_tl = NULL;
 293         if (sl) {
 294                 n = d->rttavg <<= 1;
 295                 if (n > MAXTIMER)
 296                         d->rttavg = MAXTIMER;
 297         }
 298
 299         d->timer.expires = jiffies + TIMERTICK;
 300         add_timer(&d->timer);
 301
 302         spin_unlock_irqrestore(&d->lock, flags);
 303
 304         aoenet_xmit(sl);
 305 }
 306
 307 static void
 308 ataid_complete(struct aoedev *d, unsigned char *id)
 309 {
 310         u64 ssize;
 311         u16 n;
 312
 313         /* word 83: command set supported */
 314         n = le16_to_cpup((__le16 *) &id[83<<1]);
 315
 316         /* word 86: command set/feature enabled */
 317         n |= le16_to_cpup((__le16 *) &id[86<<1]);
 318
 319         if (n & (1<<10)) {      /* bit 10: LBA 48 */
 320                 d->flags |= DEVFL_EXT;
 321
 322                 /* word 100: number lba48 sectors */
 323                 ssize = le64_to_cpup((__le64 *) &id[100<<1]);
 324
 325                 /* set as in ide-disk.c:init_idedisk_capacity */
 326                 d->geo.cylinders = ssize;
 327                 d->geo.cylinders /= (255 * 63);
 328                 d->geo.heads = 255;
 329                 d->geo.sectors = 63;
 330         } else {
 331                 d->flags &= ~DEVFL_EXT;
 332
 333                 /* number lba28 sectors */
 334                 ssize = le32_to_cpup((__le32 *) &id[60<<1]);
 335
 336                 /* NOTE: obsolete in ATA 6 */
 337                 d->geo.cylinders = le16_to_cpup((__le16 *) &id[54<<1]);
 338                 d->geo.heads = le16_to_cpup((__le16 *) &id[55<<1]);
 339                 d->geo.sectors = le16_to_cpup((__le16 *) &id[56<<1]);
 340         }
 341         d->ssize = ssize;
 342         d->geo.start = 0;
 343         if (d->gd != NULL) {
 344                 d->gd->capacity = ssize;
 345                 d->flags |= DEVFL_UP;
 346                 return;
 347         }
 348         if (d->flags & DEVFL_WORKON) {
 349                 printk(KERN_INFO "aoe: ataid_complete: can't schedule work, it's already on!  "
 350                         "(This really shouldn't happen).\n");
 351                 return;
 352         }
 353         INIT_WORK(&d->work, aoeblk_gdalloc, d);
 354         schedule_work(&d->work);
 355         d->flags |= DEVFL_WORKON;
 356 }
 357
 358 static void
 359 calc_rttavg(struct aoedev *d, int rtt)
 360 {
 361         register long n;
 362
 363         n = rtt;
 364         if (n < MINTIMER)
 365                 n = MINTIMER;
 366         else if (n > MAXTIMER)
 367                 n = MAXTIMER;
 368
 369         /* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
 370         n -= d->rttavg;
 371         d->rttavg += n >> 2;
 372 }
 373
 374 void
 375 aoecmd_ata_rsp(struct sk_buff *skb)
 376 {
 377         struct aoedev *d;
 378         struct aoe_hdr *hin;
 379         struct aoe_atahdr *ahin, *ahout;
 380         struct frame *f;
 381         struct buf *buf;
 382         struct sk_buff *sl;
 383         register long n;
 384         ulong flags;
 385         char ebuf[128];
 386         u16 aoemajor;
 387
 388         hin = (struct aoe_hdr *) skb->mac.raw;
 389         aoemajor = be16_to_cpu(hin->major);
 390         d = aoedev_by_aoeaddr(aoemajor, hin->minor);
 391         if (d == NULL) {
 392                 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
 393                         "for unknown device %d.%d\n",
 394                          aoemajor, hin->minor);
 395                 aoechr_error(ebuf);
 396                 return;
 397         }
 398
 399         spin_lock_irqsave(&d->lock, flags);
 400
 401         f = getframe(d, be32_to_cpu(hin->tag));
 402         if (f == NULL) {
 403                 spin_unlock_irqrestore(&d->lock, flags);
 404                 snprintf(ebuf, sizeof ebuf,
 405                         "%15s e%d.%d    tag=%08x@%08lx\n",
 406                         "unexpected rsp",
 407                         be16_to_cpu(hin->major),
 408                         hin->minor,
 409                         be32_to_cpu(hin->tag),
 410                         jiffies);
 411                 aoechr_error(ebuf);
 412                 return;
 413         }
 414
 415         calc_rttavg(d, tsince(f->tag));
 416
 417         ahin = (struct aoe_atahdr *) (hin+1);
 418         ahout = (struct aoe_atahdr *) (f->data + sizeof(struct aoe_hdr));
 419         buf = f->buf;
 420
 421         if (ahin->cmdstat & 0xa9) {     /* these bits cleared on success */
 422                 printk(KERN_CRIT "aoe: aoecmd_ata_rsp: ata error cmd=%2.2Xh "
 423                         "stat=%2.2Xh from e%ld.%ld\n",
 424                         ahout->cmdstat, ahin->cmdstat,
 425                         d->aoemajor, d->aoeminor);
 426                 if (buf)
 427                         buf->flags |= BUFFL_FAIL;
 428         } else {
 429                 switch (ahout->cmdstat) {
 430                 case WIN_READ:
 431                 case WIN_READ_EXT:
 432                         n = ahout->scnt << 9;
 433                         if (skb->len - sizeof *hin - sizeof *ahin < n) {
 434                                 printk(KERN_CRIT "aoe: aoecmd_ata_rsp: runt "
 435                                         "ata data size in read.  skb->len=%d\n",
 436                                         skb->len);
 437                                 /* fail frame f?  just returning will rexmit. */
 438                                 spin_unlock_irqrestore(&d->lock, flags);
 439                                 return;
 440                         }
 441                         memcpy(f->bufaddr, ahin+1, n);
 442                 case WIN_WRITE:
 443                 case WIN_WRITE_EXT:
 444                         break;
 445                 case WIN_IDENTIFY:
 446                         if (skb->len - sizeof *hin - sizeof *ahin < 512) {
 447                                 printk(KERN_INFO "aoe: aoecmd_ata_rsp: runt data size "
 448                                         "in ataid.  skb->len=%d\n", skb->len);
 449                                 spin_unlock_irqrestore(&d->lock, flags);
 450                                 return;
 451                         }
 452                         ataid_complete(d, (char *) (ahin+1));
 453                         /* d->flags |= DEVFL_WC_UPDATE; */
 454                         break;
 455                 default:
 456                         printk(KERN_INFO "aoe: aoecmd_ata_rsp: unrecognized "
 457                                "outbound ata command %2.2Xh for %d.%d\n",
 458                                ahout->cmdstat,
 459                                be16_to_cpu(hin->major),
 460                                hin->minor);
 461                 }
 462         }
 463
 464         if (buf) {
 465                 buf->nframesout -= 1;
 466                 if (buf->nframesout == 0 && buf->resid == 0) {
 467                         unsigned long duration = jiffies - buf->start_time;
 468                         unsigned long n_sect = buf->bio->bi_size >> 9;
 469                         struct gendisk *disk = d->gd;
 470
 471                         if (bio_data_dir(buf->bio) == WRITE) {
 472                                 disk_stat_inc(disk, writes);
 473                                 disk_stat_add(disk, write_ticks, duration);
 474                                 disk_stat_add(disk, write_sectors, n_sect);
 475                         } else {
 476                                 disk_stat_inc(disk, reads);
 477                                 disk_stat_add(disk, read_ticks, duration);
 478                                 disk_stat_add(disk, read_sectors, n_sect);
 479                         }
 480                         disk_stat_add(disk, io_ticks, duration);
 481                         n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
 482                         bio_endio(buf->bio, buf->bio->bi_size, n);
 483                         mempool_free(buf, d->bufpool);
 484                 }
 485         }
 486
 487         f->buf = NULL;
 488         f->tag = FREETAG;
 489
 490         aoecmd_work(d);
 491
 492         sl = d->sendq_hd;
 493         d->sendq_hd = d->sendq_tl = NULL;
 494
 495         spin_unlock_irqrestore(&d->lock, flags);
 496
 497         aoenet_xmit(sl);
 498 }
 499
 500 void
 501 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
 502 {
 503         struct aoe_hdr *h;
 504         struct aoe_cfghdr *ch;
 505         struct sk_buff *skb, *sl;
 506         struct net_device *ifp;
 507
 508         sl = NULL;
 509
 510         read_lock(&dev_base_lock);
 511         for (ifp = dev_base; ifp; dev_put(ifp), ifp = ifp->next) {
 512                 dev_hold(ifp);
 513                 if (!is_aoe_netif(ifp))
 514                         continue;
 515
 516                 skb = new_skb(ifp, sizeof *h + sizeof *ch);
 517                 if (skb == NULL) {
 518                         printk(KERN_INFO "aoe: aoecmd_cfg: skb alloc failure\n");
 519                         continue;
 520                 }
 521                 h = (struct aoe_hdr *) skb->mac.raw;
 522                 memset(h, 0, sizeof *h + sizeof *ch);
 523
 524                 memset(h->dst, 0xff, sizeof h->dst);
 525                 memcpy(h->src, ifp->dev_addr, sizeof h->src);
 526                 h->type = __constant_cpu_to_be16(ETH_P_AOE);
 527                 h->verfl = AOE_HVER;
 528                 h->major = cpu_to_be16(aoemajor);
 529                 h->minor = aoeminor;
 530                 h->cmd = AOECMD_CFG;
 531
 532                 skb->next = sl;
 533                 sl = skb;
 534         }
 535         read_unlock(&dev_base_lock);
 536
 537         aoenet_xmit(sl);
 538 }
 539
 540 /*
 541  * Since we only call this in one place (and it only prepares one frame)
 542  * we just return the skb.  Usually we'd chain it up to the aoedev sendq.
 543  */
 544 static struct sk_buff *
 545 aoecmd_ata_id(struct aoedev *d)
 546 {
 547         struct aoe_hdr *h;
 548         struct aoe_atahdr *ah;
 549         struct frame *f;
 550         struct sk_buff *skb;
 551
 552         f = getframe(d, FREETAG);
 553         if (f == NULL) {
 554                 printk(KERN_CRIT "aoe: aoecmd_ata_id: can't get a frame.  "
 555                         "This shouldn't happen.\n");
 556                 return NULL;
 557         }
 558
 559         /* initialize the headers & frame */
 560         h = (struct aoe_hdr *) f->data;
 561         ah = (struct aoe_atahdr *) (h+1);
 562         f->ndata = sizeof *h + sizeof *ah;
 563         memset(h, 0, f->ndata);
 564         f->tag = aoehdr_atainit(d, h);
 565         f->waited = 0;
 566         f->writedatalen = 0;
 567
 568         /* this message initializes the device, so we reset the rttavg */
 569         d->rttavg = MAXTIMER;
 570
 571         /* set up ata header */
 572         ah->scnt = 1;
 573         ah->cmdstat = WIN_IDENTIFY;
 574         ah->lba3 = 0xa0;
 575
 576         skb = skb_prepare(d, f);
 577
 578         /* we now want to start the rexmit tracking */
 579         d->flags &= ~DEVFL_TKILL;
 580         d->timer.data = (ulong) d;
 581         d->timer.function = rexmit_timer;
 582         d->timer.expires = jiffies + TIMERTICK;
 583         add_timer(&d->timer);
 584
 585         return skb;
 586 }
 587
 588 void
 589 aoecmd_cfg_rsp(struct sk_buff *skb)
 590 {
 591         struct aoedev *d;
 592         struct aoe_hdr *h;
 593         struct aoe_cfghdr *ch;
 594         ulong flags, sysminor, aoemajor;
 595         u16 bufcnt;
 596         struct sk_buff *sl;
 597         enum { MAXFRAMES = 8 };
 598
 599         h = (struct aoe_hdr *) skb->mac.raw;
 600         ch = (struct aoe_cfghdr *) (h+1);
 601
 602         /*
 603          * Enough people have their dip switches set backwards to
 604          * warrant a loud message for this special case.
 605          */
 606         aoemajor = be16_to_cpu(h->major);
 607         if (aoemajor == 0xfff) {
 608                 printk(KERN_CRIT "aoe: aoecmd_cfg_rsp: Warning: shelf "
 609                         "address is all ones.  Check shelf dip switches\n");
 610                 return;
 611         }
 612
 613         sysminor = SYSMINOR(aoemajor, h->minor);
 614         if (sysminor * AOE_PARTITIONS + AOE_PARTITIONS > MINORMASK) {
 615                 printk(KERN_INFO
 616                         "aoe: e%ld.%d: minor number too large\n",
 617                         aoemajor, (int) h->minor);
 618                 return;
 619         }
 620
 621         bufcnt = be16_to_cpu(ch->bufcnt);
 622         if (bufcnt > MAXFRAMES) /* keep it reasonable */
 623                 bufcnt = MAXFRAMES;
 624
 625         d = aoedev_set(sysminor, h->src, skb->dev, bufcnt);
 626         if (d == NULL) {
 627                 printk(KERN_INFO "aoe: aoecmd_cfg_rsp: device set failure\n");
 628                 return;
 629         }
 630
 631         spin_lock_irqsave(&d->lock, flags);
 632
 633         if (d->flags & (DEVFL_UP | DEVFL_CLOSEWAIT)) {
 634                 spin_unlock_irqrestore(&d->lock, flags);
 635                 return;
 636         }
 637
 638         d->fw_ver = be16_to_cpu(ch->fwver);
 639
 640         /* we get here only if the device is new */
 641         sl = aoecmd_ata_id(d);
 642
 643         spin_unlock_irqrestore(&d->lock, flags);
 644
 645         aoenet_xmit(sl);
 646 }
 647