1 /* Copyright (c) 2012 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 <linux/workqueue.h> 16 #include <linux/kthread.h> 17 #include <net/net_namespace.h> 18 #include <asm/unaligned.h> 19 #include <linux/uio.h> 20 #include "aoe.h" 21 22 #define MAXIOC (8192) /* default meant to avoid most soft lockups */ 23 24 static void ktcomplete(struct frame *, struct sk_buff *); 25 static int count_targets(struct aoedev *d, int *untainted); 26 27 static struct buf *nextbuf(struct aoedev *); 28 29 static int aoe_deadsecs = 60 * 3; 30 module_param(aoe_deadsecs, int, 0644); 31 MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev."); 32 33 static int aoe_maxout = 64; 34 module_param(aoe_maxout, int, 0644); 35 MODULE_PARM_DESC(aoe_maxout, 36 "Only aoe_maxout outstanding packets for every MAC on eX.Y."); 37 38 static wait_queue_head_t ktiowq; 39 static struct ktstate kts; 40 41 /* io completion queue */ 42 static struct { 43 struct list_head head; 44 spinlock_t lock; 45 } iocq; 46 47 static struct page *empty_page; 48 49 static struct sk_buff * 50 new_skb(ulong len) 51 { 52 struct sk_buff *skb; 53 54 skb = alloc_skb(len + MAX_HEADER, GFP_ATOMIC); 55 if (skb) { 56 skb_reserve(skb, MAX_HEADER); 57 skb_reset_mac_header(skb); 58 skb_reset_network_header(skb); 59 skb->protocol = __constant_htons(ETH_P_AOE); 60 skb_checksum_none_assert(skb); 61 } 62 return skb; 63 } 64 65 static struct frame * 66 getframe_deferred(struct aoedev *d, u32 tag) 67 { 68 struct list_head *head, *pos, *nx; 69 struct frame *f; 70 71 head = &d->rexmitq; 72 list_for_each_safe(pos, nx, head) { 73 f = list_entry(pos, struct frame, head); 74 if (f->tag == tag) { 75 list_del(pos); 76 return f; 77 } 78 } 79 return NULL; 80 } 81 82 static struct frame * 83 getframe(struct aoedev *d, u32 tag) 84 { 85 struct frame *f; 86 struct list_head *head, *pos, *nx; 87 u32 n; 88 89 n = tag % NFACTIVE; 90 head = &d->factive[n]; 91 list_for_each_safe(pos, nx, head) { 92 f = list_entry(pos, struct frame, head); 93 if (f->tag == tag) { 94 list_del(pos); 95 return f; 96 } 97 } 98 return NULL; 99 } 100 101 /* 102 * Leave the top bit clear so we have tagspace for userland. 103 * The bottom 16 bits are the xmit tick for rexmit/rttavg processing. 104 * This driver reserves tag -1 to mean "unused frame." 105 */ 106 static int 107 newtag(struct aoedev *d) 108 { 109 register ulong n; 110 111 n = jiffies & 0xffff; 112 return n |= (++d->lasttag & 0x7fff) << 16; 113 } 114 115 static u32 116 aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h) 117 { 118 u32 host_tag = newtag(d); 119 120 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src); 121 memcpy(h->dst, t->addr, sizeof h->dst); 122 h->type = __constant_cpu_to_be16(ETH_P_AOE); 123 h->verfl = AOE_HVER; 124 h->major = cpu_to_be16(d->aoemajor); 125 h->minor = d->aoeminor; 126 h->cmd = AOECMD_ATA; 127 h->tag = cpu_to_be32(host_tag); 128 129 return host_tag; 130 } 131 132 static inline void 133 put_lba(struct aoe_atahdr *ah, sector_t lba) 134 { 135 ah->lba0 = lba; 136 ah->lba1 = lba >>= 8; 137 ah->lba2 = lba >>= 8; 138 ah->lba3 = lba >>= 8; 139 ah->lba4 = lba >>= 8; 140 ah->lba5 = lba >>= 8; 141 } 142 143 static struct aoeif * 144 ifrotate(struct aoetgt *t) 145 { 146 struct aoeif *ifp; 147 148 ifp = t->ifp; 149 ifp++; 150 if (ifp >= &t->ifs[NAOEIFS] || ifp->nd == NULL) 151 ifp = t->ifs; 152 if (ifp->nd == NULL) 153 return NULL; 154 return t->ifp = ifp; 155 } 156 157 static void 158 skb_pool_put(struct aoedev *d, struct sk_buff *skb) 159 { 160 __skb_queue_tail(&d->skbpool, skb); 161 } 162 163 static struct sk_buff * 164 skb_pool_get(struct aoedev *d) 165 { 166 struct sk_buff *skb = skb_peek(&d->skbpool); 167 168 if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) { 169 __skb_unlink(skb, &d->skbpool); 170 return skb; 171 } 172 if (skb_queue_len(&d->skbpool) < NSKBPOOLMAX && 173 (skb = new_skb(ETH_ZLEN))) 174 return skb; 175 176 return NULL; 177 } 178 179 void 180 aoe_freetframe(struct frame *f) 181 { 182 struct aoetgt *t; 183 184 t = f->t; 185 f->buf = NULL; 186 f->lba = 0; 187 f->bv = NULL; 188 f->r_skb = NULL; 189 f->flags = 0; 190 list_add(&f->head, &t->ffree); 191 } 192 193 static struct frame * 194 newtframe(struct aoedev *d, struct aoetgt *t) 195 { 196 struct frame *f; 197 struct sk_buff *skb; 198 struct list_head *pos; 199 200 if (list_empty(&t->ffree)) { 201 if (t->falloc >= NSKBPOOLMAX*2) 202 return NULL; 203 f = kcalloc(1, sizeof(*f), GFP_ATOMIC); 204 if (f == NULL) 205 return NULL; 206 t->falloc++; 207 f->t = t; 208 } else { 209 pos = t->ffree.next; 210 list_del(pos); 211 f = list_entry(pos, struct frame, head); 212 } 213 214 skb = f->skb; 215 if (skb == NULL) { 216 f->skb = skb = new_skb(ETH_ZLEN); 217 if (!skb) { 218 bail: aoe_freetframe(f); 219 return NULL; 220 } 221 } 222 223 if (atomic_read(&skb_shinfo(skb)->dataref) != 1) { 224 skb = skb_pool_get(d); 225 if (skb == NULL) 226 goto bail; 227 skb_pool_put(d, f->skb); 228 f->skb = skb; 229 } 230 231 skb->truesize -= skb->data_len; 232 skb_shinfo(skb)->nr_frags = skb->data_len = 0; 233 skb_trim(skb, 0); 234 return f; 235 } 236 237 static struct frame * 238 newframe(struct aoedev *d) 239 { 240 struct frame *f; 241 struct aoetgt *t, **tt; 242 int totout = 0; 243 int use_tainted; 244 int has_untainted; 245 246 if (!d->targets || !d->targets[0]) { 247 printk(KERN_ERR "aoe: NULL TARGETS!\n"); 248 return NULL; 249 } 250 tt = d->tgt; /* last used target */ 251 for (use_tainted = 0, has_untainted = 0;;) { 252 tt++; 253 if (tt >= &d->targets[d->ntargets] || !*tt) 254 tt = d->targets; 255 t = *tt; 256 if (!t->taint) { 257 has_untainted = 1; 258 totout += t->nout; 259 } 260 if (t->nout < t->maxout 261 && (use_tainted || !t->taint) 262 && t->ifp->nd) { 263 f = newtframe(d, t); 264 if (f) { 265 ifrotate(t); 266 d->tgt = tt; 267 return f; 268 } 269 } 270 if (tt == d->tgt) { /* we've looped and found nada */ 271 if (!use_tainted && !has_untainted) 272 use_tainted = 1; 273 else 274 break; 275 } 276 } 277 if (totout == 0) { 278 d->kicked++; 279 d->flags |= DEVFL_KICKME; 280 } 281 return NULL; 282 } 283 284 static void 285 skb_fillup(struct sk_buff *skb, struct bio_vec *bv, ulong off, ulong cnt) 286 { 287 int frag = 0; 288 ulong fcnt; 289 loop: 290 fcnt = bv->bv_len - (off - bv->bv_offset); 291 if (fcnt > cnt) 292 fcnt = cnt; 293 skb_fill_page_desc(skb, frag++, bv->bv_page, off, fcnt); 294 cnt -= fcnt; 295 if (cnt <= 0) 296 return; 297 bv++; 298 off = bv->bv_offset; 299 goto loop; 300 } 301 302 static void 303 fhash(struct frame *f) 304 { 305 struct aoedev *d = f->t->d; 306 u32 n; 307 308 n = f->tag % NFACTIVE; 309 list_add_tail(&f->head, &d->factive[n]); 310 } 311 312 static void 313 ata_rw_frameinit(struct frame *f) 314 { 315 struct aoetgt *t; 316 struct aoe_hdr *h; 317 struct aoe_atahdr *ah; 318 struct sk_buff *skb; 319 char writebit, extbit; 320 321 skb = f->skb; 322 h = (struct aoe_hdr *) skb_mac_header(skb); 323 ah = (struct aoe_atahdr *) (h + 1); 324 skb_put(skb, sizeof(*h) + sizeof(*ah)); 325 memset(h, 0, skb->len); 326 327 writebit = 0x10; 328 extbit = 0x4; 329 330 t = f->t; 331 f->tag = aoehdr_atainit(t->d, t, h); 332 fhash(f); 333 t->nout++; 334 f->waited = 0; 335 f->waited_total = 0; 336 if (f->buf) 337 f->lba = f->buf->sector; 338 339 /* set up ata header */ 340 ah->scnt = f->bcnt >> 9; 341 put_lba(ah, f->lba); 342 if (t->d->flags & DEVFL_EXT) { 343 ah->aflags |= AOEAFL_EXT; 344 } else { 345 extbit = 0; 346 ah->lba3 &= 0x0f; 347 ah->lba3 |= 0xe0; /* LBA bit + obsolete 0xa0 */ 348 } 349 if (f->buf && bio_data_dir(f->buf->bio) == WRITE) { 350 skb_fillup(skb, f->bv, f->bv_off, f->bcnt); 351 ah->aflags |= AOEAFL_WRITE; 352 skb->len += f->bcnt; 353 skb->data_len = f->bcnt; 354 skb->truesize += f->bcnt; 355 t->wpkts++; 356 } else { 357 t->rpkts++; 358 writebit = 0; 359 } 360 361 ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit; 362 skb->dev = t->ifp->nd; 363 } 364 365 static int 366 aoecmd_ata_rw(struct aoedev *d) 367 { 368 struct frame *f; 369 struct buf *buf; 370 struct aoetgt *t; 371 struct sk_buff *skb; 372 struct sk_buff_head queue; 373 ulong bcnt, fbcnt; 374 375 buf = nextbuf(d); 376 if (buf == NULL) 377 return 0; 378 f = newframe(d); 379 if (f == NULL) 380 return 0; 381 t = *d->tgt; 382 bcnt = d->maxbcnt; 383 if (bcnt == 0) 384 bcnt = DEFAULTBCNT; 385 if (bcnt > buf->resid) 386 bcnt = buf->resid; 387 fbcnt = bcnt; 388 f->bv = buf->bv; 389 f->bv_off = f->bv->bv_offset + (f->bv->bv_len - buf->bv_resid); 390 do { 391 if (fbcnt < buf->bv_resid) { 392 buf->bv_resid -= fbcnt; 393 buf->resid -= fbcnt; 394 break; 395 } 396 fbcnt -= buf->bv_resid; 397 buf->resid -= buf->bv_resid; 398 if (buf->resid == 0) { 399 d->ip.buf = NULL; 400 break; 401 } 402 buf->bv++; 403 buf->bv_resid = buf->bv->bv_len; 404 WARN_ON(buf->bv_resid == 0); 405 } while (fbcnt); 406 407 /* initialize the headers & frame */ 408 f->buf = buf; 409 f->bcnt = bcnt; 410 ata_rw_frameinit(f); 411 412 /* mark all tracking fields and load out */ 413 buf->nframesout += 1; 414 buf->sector += bcnt >> 9; 415 416 skb = skb_clone(f->skb, GFP_ATOMIC); 417 if (skb) { 418 do_gettimeofday(&f->sent); 419 f->sent_jiffs = (u32) jiffies; 420 __skb_queue_head_init(&queue); 421 __skb_queue_tail(&queue, skb); 422 aoenet_xmit(&queue); 423 } 424 return 1; 425 } 426 427 /* some callers cannot sleep, and they can call this function, 428 * transmitting the packets later, when interrupts are on 429 */ 430 static void 431 aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue) 432 { 433 struct aoe_hdr *h; 434 struct aoe_cfghdr *ch; 435 struct sk_buff *skb; 436 struct net_device *ifp; 437 438 rcu_read_lock(); 439 for_each_netdev_rcu(&init_net, ifp) { 440 dev_hold(ifp); 441 if (!is_aoe_netif(ifp)) 442 goto cont; 443 444 skb = new_skb(sizeof *h + sizeof *ch); 445 if (skb == NULL) { 446 printk(KERN_INFO "aoe: skb alloc failure\n"); 447 goto cont; 448 } 449 skb_put(skb, sizeof *h + sizeof *ch); 450 skb->dev = ifp; 451 __skb_queue_tail(queue, skb); 452 h = (struct aoe_hdr *) skb_mac_header(skb); 453 memset(h, 0, sizeof *h + sizeof *ch); 454 455 memset(h->dst, 0xff, sizeof h->dst); 456 memcpy(h->src, ifp->dev_addr, sizeof h->src); 457 h->type = __constant_cpu_to_be16(ETH_P_AOE); 458 h->verfl = AOE_HVER; 459 h->major = cpu_to_be16(aoemajor); 460 h->minor = aoeminor; 461 h->cmd = AOECMD_CFG; 462 463 cont: 464 dev_put(ifp); 465 } 466 rcu_read_unlock(); 467 } 468 469 static void 470 resend(struct aoedev *d, struct frame *f) 471 { 472 struct sk_buff *skb; 473 struct sk_buff_head queue; 474 struct aoe_hdr *h; 475 struct aoe_atahdr *ah; 476 struct aoetgt *t; 477 char buf[128]; 478 u32 n; 479 480 t = f->t; 481 n = newtag(d); 482 skb = f->skb; 483 if (ifrotate(t) == NULL) { 484 /* probably can't happen, but set it up to fail anyway */ 485 pr_info("aoe: resend: no interfaces to rotate to.\n"); 486 ktcomplete(f, NULL); 487 return; 488 } 489 h = (struct aoe_hdr *) skb_mac_header(skb); 490 ah = (struct aoe_atahdr *) (h+1); 491 492 if (!(f->flags & FFL_PROBE)) { 493 snprintf(buf, sizeof(buf), 494 "%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n", 495 "retransmit", d->aoemajor, d->aoeminor, 496 f->tag, jiffies, n, 497 h->src, h->dst, t->nout); 498 aoechr_error(buf); 499 } 500 501 f->tag = n; 502 fhash(f); 503 h->tag = cpu_to_be32(n); 504 memcpy(h->dst, t->addr, sizeof h->dst); 505 memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src); 506 507 skb->dev = t->ifp->nd; 508 skb = skb_clone(skb, GFP_ATOMIC); 509 if (skb == NULL) 510 return; 511 do_gettimeofday(&f->sent); 512 f->sent_jiffs = (u32) jiffies; 513 __skb_queue_head_init(&queue); 514 __skb_queue_tail(&queue, skb); 515 aoenet_xmit(&queue); 516 } 517 518 static int 519 tsince_hr(struct frame *f) 520 { 521 struct timeval now; 522 int n; 523 524 do_gettimeofday(&now); 525 n = now.tv_usec - f->sent.tv_usec; 526 n += (now.tv_sec - f->sent.tv_sec) * USEC_PER_SEC; 527 528 if (n < 0) 529 n = -n; 530 531 /* For relatively long periods, use jiffies to avoid 532 * discrepancies caused by updates to the system time. 533 * 534 * On system with HZ of 1000, 32-bits is over 49 days 535 * worth of jiffies, or over 71 minutes worth of usecs. 536 * 537 * Jiffies overflow is handled by subtraction of unsigned ints: 538 * (gdb) print (unsigned) 2 - (unsigned) 0xfffffffe 539 * $3 = 4 540 * (gdb) 541 */ 542 if (n > USEC_PER_SEC / 4) { 543 n = ((u32) jiffies) - f->sent_jiffs; 544 n *= USEC_PER_SEC / HZ; 545 } 546 547 return n; 548 } 549 550 static int 551 tsince(u32 tag) 552 { 553 int n; 554 555 n = jiffies & 0xffff; 556 n -= tag & 0xffff; 557 if (n < 0) 558 n += 1<<16; 559 return jiffies_to_usecs(n + 1); 560 } 561 562 static struct aoeif * 563 getif(struct aoetgt *t, struct net_device *nd) 564 { 565 struct aoeif *p, *e; 566 567 p = t->ifs; 568 e = p + NAOEIFS; 569 for (; p < e; p++) 570 if (p->nd == nd) 571 return p; 572 return NULL; 573 } 574 575 static void 576 ejectif(struct aoetgt *t, struct aoeif *ifp) 577 { 578 struct aoeif *e; 579 struct net_device *nd; 580 ulong n; 581 582 nd = ifp->nd; 583 e = t->ifs + NAOEIFS - 1; 584 n = (e - ifp) * sizeof *ifp; 585 memmove(ifp, ifp+1, n); 586 e->nd = NULL; 587 dev_put(nd); 588 } 589 590 static struct frame * 591 reassign_frame(struct frame *f) 592 { 593 struct frame *nf; 594 struct sk_buff *skb; 595 596 nf = newframe(f->t->d); 597 if (!nf) 598 return NULL; 599 if (nf->t == f->t) { 600 aoe_freetframe(nf); 601 return NULL; 602 } 603 604 skb = nf->skb; 605 nf->skb = f->skb; 606 nf->buf = f->buf; 607 nf->bcnt = f->bcnt; 608 nf->lba = f->lba; 609 nf->bv = f->bv; 610 nf->bv_off = f->bv_off; 611 nf->waited = 0; 612 nf->waited_total = f->waited_total; 613 nf->sent = f->sent; 614 nf->sent_jiffs = f->sent_jiffs; 615 f->skb = skb; 616 617 return nf; 618 } 619 620 static void 621 probe(struct aoetgt *t) 622 { 623 struct aoedev *d; 624 struct frame *f; 625 struct sk_buff *skb; 626 struct sk_buff_head queue; 627 size_t n, m; 628 int frag; 629 630 d = t->d; 631 f = newtframe(d, t); 632 if (!f) { 633 pr_err("%s %pm for e%ld.%d: %s\n", 634 "aoe: cannot probe remote address", 635 t->addr, 636 (long) d->aoemajor, d->aoeminor, 637 "no frame available"); 638 return; 639 } 640 f->flags |= FFL_PROBE; 641 ifrotate(t); 642 f->bcnt = t->d->maxbcnt ? t->d->maxbcnt : DEFAULTBCNT; 643 ata_rw_frameinit(f); 644 skb = f->skb; 645 for (frag = 0, n = f->bcnt; n > 0; ++frag, n -= m) { 646 if (n < PAGE_SIZE) 647 m = n; 648 else 649 m = PAGE_SIZE; 650 skb_fill_page_desc(skb, frag, empty_page, 0, m); 651 } 652 skb->len += f->bcnt; 653 skb->data_len = f->bcnt; 654 skb->truesize += f->bcnt; 655 656 skb = skb_clone(f->skb, GFP_ATOMIC); 657 if (skb) { 658 do_gettimeofday(&f->sent); 659 f->sent_jiffs = (u32) jiffies; 660 __skb_queue_head_init(&queue); 661 __skb_queue_tail(&queue, skb); 662 aoenet_xmit(&queue); 663 } 664 } 665 666 static long 667 rto(struct aoedev *d) 668 { 669 long t; 670 671 t = 2 * d->rttavg >> RTTSCALE; 672 t += 8 * d->rttdev >> RTTDSCALE; 673 if (t == 0) 674 t = 1; 675 676 return t; 677 } 678 679 static void 680 rexmit_deferred(struct aoedev *d) 681 { 682 struct aoetgt *t; 683 struct frame *f; 684 struct frame *nf; 685 struct list_head *pos, *nx, *head; 686 int since; 687 int untainted; 688 689 count_targets(d, &untainted); 690 691 head = &d->rexmitq; 692 list_for_each_safe(pos, nx, head) { 693 f = list_entry(pos, struct frame, head); 694 t = f->t; 695 if (t->taint) { 696 if (!(f->flags & FFL_PROBE)) { 697 nf = reassign_frame(f); 698 if (nf) { 699 if (t->nout_probes == 0 700 && untainted > 0) { 701 probe(t); 702 t->nout_probes++; 703 } 704 list_replace(&f->head, &nf->head); 705 pos = &nf->head; 706 aoe_freetframe(f); 707 f = nf; 708 t = f->t; 709 } 710 } else if (untainted < 1) { 711 /* don't probe w/o other untainted aoetgts */ 712 goto stop_probe; 713 } else if (tsince_hr(f) < t->taint * rto(d)) { 714 /* reprobe slowly when taint is high */ 715 continue; 716 } 717 } else if (f->flags & FFL_PROBE) { 718 stop_probe: /* don't probe untainted aoetgts */ 719 list_del(pos); 720 aoe_freetframe(f); 721 /* leaving d->kicked, because this is routine */ 722 f->t->d->flags |= DEVFL_KICKME; 723 continue; 724 } 725 if (t->nout >= t->maxout) 726 continue; 727 list_del(pos); 728 t->nout++; 729 if (f->flags & FFL_PROBE) 730 t->nout_probes++; 731 since = tsince_hr(f); 732 f->waited += since; 733 f->waited_total += since; 734 resend(d, f); 735 } 736 } 737 738 /* An aoetgt accumulates demerits quickly, and successful 739 * probing redeems the aoetgt slowly. 740 */ 741 static void 742 scorn(struct aoetgt *t) 743 { 744 int n; 745 746 n = t->taint++; 747 t->taint += t->taint * 2; 748 if (n > t->taint) 749 t->taint = n; 750 if (t->taint > MAX_TAINT) 751 t->taint = MAX_TAINT; 752 } 753 754 static int 755 count_targets(struct aoedev *d, int *untainted) 756 { 757 int i, good; 758 759 for (i = good = 0; i < d->ntargets && d->targets[i]; ++i) 760 if (d->targets[i]->taint == 0) 761 good++; 762 763 if (untainted) 764 *untainted = good; 765 return i; 766 } 767 768 static void 769 rexmit_timer(ulong vp) 770 { 771 struct aoedev *d; 772 struct aoetgt *t; 773 struct aoeif *ifp; 774 struct frame *f; 775 struct list_head *head, *pos, *nx; 776 LIST_HEAD(flist); 777 register long timeout; 778 ulong flags, n; 779 int i; 780 int utgts; /* number of aoetgt descriptors (not slots) */ 781 int since; 782 783 d = (struct aoedev *) vp; 784 785 spin_lock_irqsave(&d->lock, flags); 786 787 /* timeout based on observed timings and variations */ 788 timeout = rto(d); 789 790 utgts = count_targets(d, NULL); 791 792 if (d->flags & DEVFL_TKILL) { 793 spin_unlock_irqrestore(&d->lock, flags); 794 return; 795 } 796 797 /* collect all frames to rexmit into flist */ 798 for (i = 0; i < NFACTIVE; i++) { 799 head = &d->factive[i]; 800 list_for_each_safe(pos, nx, head) { 801 f = list_entry(pos, struct frame, head); 802 if (tsince_hr(f) < timeout) 803 break; /* end of expired frames */ 804 /* move to flist for later processing */ 805 list_move_tail(pos, &flist); 806 } 807 } 808 809 /* process expired frames */ 810 while (!list_empty(&flist)) { 811 pos = flist.next; 812 f = list_entry(pos, struct frame, head); 813 since = tsince_hr(f); 814 n = f->waited_total + since; 815 n /= USEC_PER_SEC; 816 if (aoe_deadsecs 817 && n > aoe_deadsecs 818 && !(f->flags & FFL_PROBE)) { 819 /* Waited too long. Device failure. 820 * Hang all frames on first hash bucket for downdev 821 * to clean up. 822 */ 823 list_splice(&flist, &d->factive[0]); 824 aoedev_downdev(d); 825 goto out; 826 } 827 828 t = f->t; 829 n = f->waited + since; 830 n /= USEC_PER_SEC; 831 if (aoe_deadsecs && utgts > 0 832 && (n > aoe_deadsecs / utgts || n > HARD_SCORN_SECS)) 833 scorn(t); /* avoid this target */ 834 835 if (t->maxout != 1) { 836 t->ssthresh = t->maxout / 2; 837 t->maxout = 1; 838 } 839 840 if (f->flags & FFL_PROBE) { 841 t->nout_probes--; 842 } else { 843 ifp = getif(t, f->skb->dev); 844 if (ifp && ++ifp->lost > (t->nframes << 1) 845 && (ifp != t->ifs || t->ifs[1].nd)) { 846 ejectif(t, ifp); 847 ifp = NULL; 848 } 849 } 850 list_move_tail(pos, &d->rexmitq); 851 t->nout--; 852 } 853 rexmit_deferred(d); 854 855 out: 856 if ((d->flags & DEVFL_KICKME) && d->blkq) { 857 d->flags &= ~DEVFL_KICKME; 858 d->blkq->request_fn(d->blkq); 859 } 860 861 d->timer.expires = jiffies + TIMERTICK; 862 add_timer(&d->timer); 863 864 spin_unlock_irqrestore(&d->lock, flags); 865 } 866 867 static unsigned long 868 rqbiocnt(struct request *r) 869 { 870 struct bio *bio; 871 unsigned long n = 0; 872 873 __rq_for_each_bio(bio, r) 874 n++; 875 return n; 876 } 877 878 /* This can be removed if we are certain that no users of the block 879 * layer will ever use zero-count pages in bios. Otherwise we have to 880 * protect against the put_page sometimes done by the network layer. 881 * 882 * See http://oss.sgi.com/archives/xfs/2007-01/msg00594.html for 883 * discussion. 884 * 885 * We cannot use get_page in the workaround, because it insists on a 886 * positive page count as a precondition. So we use _count directly. 887 */ 888 static void 889 bio_pageinc(struct bio *bio) 890 { 891 struct bio_vec *bv; 892 struct page *page; 893 int i; 894 895 bio_for_each_segment(bv, bio, i) { 896 page = bv->bv_page; 897 /* Non-zero page count for non-head members of 898 * compound pages is no longer allowed by the kernel, 899 * but this has never been seen here. 900 */ 901 if (unlikely(PageCompound(page))) 902 if (compound_trans_head(page) != page) { 903 pr_crit("page tail used for block I/O\n"); 904 BUG(); 905 } 906 atomic_inc(&page->_count); 907 } 908 } 909 910 static void 911 bio_pagedec(struct bio *bio) 912 { 913 struct bio_vec *bv; 914 int i; 915 916 bio_for_each_segment(bv, bio, i) 917 atomic_dec(&bv->bv_page->_count); 918 } 919 920 static void 921 bufinit(struct buf *buf, struct request *rq, struct bio *bio) 922 { 923 struct bio_vec *bv; 924 925 memset(buf, 0, sizeof(*buf)); 926 buf->rq = rq; 927 buf->bio = bio; 928 buf->resid = bio->bi_size; 929 buf->sector = bio->bi_sector; 930 bio_pageinc(bio); 931 buf->bv = bv = &bio->bi_io_vec[bio->bi_idx]; 932 buf->bv_resid = bv->bv_len; 933 WARN_ON(buf->bv_resid == 0); 934 } 935 936 static struct buf * 937 nextbuf(struct aoedev *d) 938 { 939 struct request *rq; 940 struct request_queue *q; 941 struct buf *buf; 942 struct bio *bio; 943 944 q = d->blkq; 945 if (q == NULL) 946 return NULL; /* initializing */ 947 if (d->ip.buf) 948 return d->ip.buf; 949 rq = d->ip.rq; 950 if (rq == NULL) { 951 rq = blk_peek_request(q); 952 if (rq == NULL) 953 return NULL; 954 blk_start_request(rq); 955 d->ip.rq = rq; 956 d->ip.nxbio = rq->bio; 957 rq->special = (void *) rqbiocnt(rq); 958 } 959 buf = mempool_alloc(d->bufpool, GFP_ATOMIC); 960 if (buf == NULL) { 961 pr_err("aoe: nextbuf: unable to mempool_alloc!\n"); 962 return NULL; 963 } 964 bio = d->ip.nxbio; 965 bufinit(buf, rq, bio); 966 bio = bio->bi_next; 967 d->ip.nxbio = bio; 968 if (bio == NULL) 969 d->ip.rq = NULL; 970 return d->ip.buf = buf; 971 } 972 973 /* enters with d->lock held */ 974 void 975 aoecmd_work(struct aoedev *d) 976 { 977 rexmit_deferred(d); 978 while (aoecmd_ata_rw(d)) 979 ; 980 } 981 982 /* this function performs work that has been deferred until sleeping is OK 983 */ 984 void 985 aoecmd_sleepwork(struct work_struct *work) 986 { 987 struct aoedev *d = container_of(work, struct aoedev, work); 988 struct block_device *bd; 989 u64 ssize; 990 991 if (d->flags & DEVFL_GDALLOC) 992 aoeblk_gdalloc(d); 993 994 if (d->flags & DEVFL_NEWSIZE) { 995 ssize = get_capacity(d->gd); 996 bd = bdget_disk(d->gd, 0); 997 if (bd) { 998 mutex_lock(&bd->bd_inode->i_mutex); 999 i_size_write(bd->bd_inode, (loff_t)ssize<<9); 1000 mutex_unlock(&bd->bd_inode->i_mutex); 1001 bdput(bd); 1002 } 1003 spin_lock_irq(&d->lock); 1004 d->flags |= DEVFL_UP; 1005 d->flags &= ~DEVFL_NEWSIZE; 1006 spin_unlock_irq(&d->lock); 1007 } 1008 } 1009 1010 static void 1011 ata_ident_fixstring(u16 *id, int ns) 1012 { 1013 u16 s; 1014 1015 while (ns-- > 0) { 1016 s = *id; 1017 *id++ = s >> 8 | s << 8; 1018 } 1019 } 1020 1021 static void 1022 ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id) 1023 { 1024 u64 ssize; 1025 u16 n; 1026 1027 /* word 83: command set supported */ 1028 n = get_unaligned_le16(&id[83 << 1]); 1029 1030 /* word 86: command set/feature enabled */ 1031 n |= get_unaligned_le16(&id[86 << 1]); 1032 1033 if (n & (1<<10)) { /* bit 10: LBA 48 */ 1034 d->flags |= DEVFL_EXT; 1035 1036 /* word 100: number lba48 sectors */ 1037 ssize = get_unaligned_le64(&id[100 << 1]); 1038 1039 /* set as in ide-disk.c:init_idedisk_capacity */ 1040 d->geo.cylinders = ssize; 1041 d->geo.cylinders /= (255 * 63); 1042 d->geo.heads = 255; 1043 d->geo.sectors = 63; 1044 } else { 1045 d->flags &= ~DEVFL_EXT; 1046 1047 /* number lba28 sectors */ 1048 ssize = get_unaligned_le32(&id[60 << 1]); 1049 1050 /* NOTE: obsolete in ATA 6 */ 1051 d->geo.cylinders = get_unaligned_le16(&id[54 << 1]); 1052 d->geo.heads = get_unaligned_le16(&id[55 << 1]); 1053 d->geo.sectors = get_unaligned_le16(&id[56 << 1]); 1054 } 1055 1056 ata_ident_fixstring((u16 *) &id[10<<1], 10); /* serial */ 1057 ata_ident_fixstring((u16 *) &id[23<<1], 4); /* firmware */ 1058 ata_ident_fixstring((u16 *) &id[27<<1], 20); /* model */ 1059 memcpy(d->ident, id, sizeof(d->ident)); 1060 1061 if (d->ssize != ssize) 1062 printk(KERN_INFO 1063 "aoe: %pm e%ld.%d v%04x has %llu sectors\n", 1064 t->addr, 1065 d->aoemajor, d->aoeminor, 1066 d->fw_ver, (long long)ssize); 1067 d->ssize = ssize; 1068 d->geo.start = 0; 1069 if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE)) 1070 return; 1071 if (d->gd != NULL) { 1072 set_capacity(d->gd, ssize); 1073 d->flags |= DEVFL_NEWSIZE; 1074 } else 1075 d->flags |= DEVFL_GDALLOC; 1076 schedule_work(&d->work); 1077 } 1078 1079 static void 1080 calc_rttavg(struct aoedev *d, struct aoetgt *t, int rtt) 1081 { 1082 register long n; 1083 1084 n = rtt; 1085 1086 /* cf. Congestion Avoidance and Control, Jacobson & Karels, 1988 */ 1087 n -= d->rttavg >> RTTSCALE; 1088 d->rttavg += n; 1089 if (n < 0) 1090 n = -n; 1091 n -= d->rttdev >> RTTDSCALE; 1092 d->rttdev += n; 1093 1094 if (!t || t->maxout >= t->nframes) 1095 return; 1096 if (t->maxout < t->ssthresh) 1097 t->maxout += 1; 1098 else if (t->nout == t->maxout && t->next_cwnd-- == 0) { 1099 t->maxout += 1; 1100 t->next_cwnd = t->maxout; 1101 } 1102 } 1103 1104 static struct aoetgt * 1105 gettgt(struct aoedev *d, char *addr) 1106 { 1107 struct aoetgt **t, **e; 1108 1109 t = d->targets; 1110 e = t + d->ntargets; 1111 for (; t < e && *t; t++) 1112 if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0) 1113 return *t; 1114 return NULL; 1115 } 1116 1117 static void 1118 bvcpy(struct bio_vec *bv, ulong off, struct sk_buff *skb, long cnt) 1119 { 1120 ulong fcnt; 1121 char *p; 1122 int soff = 0; 1123 loop: 1124 fcnt = bv->bv_len - (off - bv->bv_offset); 1125 if (fcnt > cnt) 1126 fcnt = cnt; 1127 p = page_address(bv->bv_page) + off; 1128 skb_copy_bits(skb, soff, p, fcnt); 1129 soff += fcnt; 1130 cnt -= fcnt; 1131 if (cnt <= 0) 1132 return; 1133 bv++; 1134 off = bv->bv_offset; 1135 goto loop; 1136 } 1137 1138 void 1139 aoe_end_request(struct aoedev *d, struct request *rq, int fastfail) 1140 { 1141 struct bio *bio; 1142 int bok; 1143 struct request_queue *q; 1144 1145 q = d->blkq; 1146 if (rq == d->ip.rq) 1147 d->ip.rq = NULL; 1148 do { 1149 bio = rq->bio; 1150 bok = !fastfail && test_bit(BIO_UPTODATE, &bio->bi_flags); 1151 } while (__blk_end_request(rq, bok ? 0 : -EIO, bio->bi_size)); 1152 1153 /* cf. http://lkml.org/lkml/2006/10/31/28 */ 1154 if (!fastfail) 1155 __blk_run_queue(q); 1156 } 1157 1158 static void 1159 aoe_end_buf(struct aoedev *d, struct buf *buf) 1160 { 1161 struct request *rq; 1162 unsigned long n; 1163 1164 if (buf == d->ip.buf) 1165 d->ip.buf = NULL; 1166 rq = buf->rq; 1167 bio_pagedec(buf->bio); 1168 mempool_free(buf, d->bufpool); 1169 n = (unsigned long) rq->special; 1170 rq->special = (void *) --n; 1171 if (n == 0) 1172 aoe_end_request(d, rq, 0); 1173 } 1174 1175 static void 1176 ktiocomplete(struct frame *f) 1177 { 1178 struct aoe_hdr *hin, *hout; 1179 struct aoe_atahdr *ahin, *ahout; 1180 struct buf *buf; 1181 struct sk_buff *skb; 1182 struct aoetgt *t; 1183 struct aoeif *ifp; 1184 struct aoedev *d; 1185 long n; 1186 int untainted; 1187 1188 if (f == NULL) 1189 return; 1190 1191 t = f->t; 1192 d = t->d; 1193 skb = f->r_skb; 1194 buf = f->buf; 1195 if (f->flags & FFL_PROBE) 1196 goto out; 1197 if (!skb) /* just fail the buf. */ 1198 goto noskb; 1199 1200 hout = (struct aoe_hdr *) skb_mac_header(f->skb); 1201 ahout = (struct aoe_atahdr *) (hout+1); 1202 1203 hin = (struct aoe_hdr *) skb->data; 1204 skb_pull(skb, sizeof(*hin)); 1205 ahin = (struct aoe_atahdr *) skb->data; 1206 skb_pull(skb, sizeof(*ahin)); 1207 if (ahin->cmdstat & 0xa9) { /* these bits cleared on success */ 1208 pr_err("aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n", 1209 ahout->cmdstat, ahin->cmdstat, 1210 d->aoemajor, d->aoeminor); 1211 noskb: if (buf) 1212 clear_bit(BIO_UPTODATE, &buf->bio->bi_flags); 1213 goto out; 1214 } 1215 1216 n = ahout->scnt << 9; 1217 switch (ahout->cmdstat) { 1218 case ATA_CMD_PIO_READ: 1219 case ATA_CMD_PIO_READ_EXT: 1220 if (skb->len < n) { 1221 pr_err("%s e%ld.%d. skb->len=%d need=%ld\n", 1222 "aoe: runt data size in read from", 1223 (long) d->aoemajor, d->aoeminor, 1224 skb->len, n); 1225 clear_bit(BIO_UPTODATE, &buf->bio->bi_flags); 1226 break; 1227 } 1228 bvcpy(f->bv, f->bv_off, skb, n); 1229 case ATA_CMD_PIO_WRITE: 1230 case ATA_CMD_PIO_WRITE_EXT: 1231 spin_lock_irq(&d->lock); 1232 ifp = getif(t, skb->dev); 1233 if (ifp) 1234 ifp->lost = 0; 1235 spin_unlock_irq(&d->lock); 1236 break; 1237 case ATA_CMD_ID_ATA: 1238 if (skb->len < 512) { 1239 pr_info("%s e%ld.%d. skb->len=%d need=512\n", 1240 "aoe: runt data size in ataid from", 1241 (long) d->aoemajor, d->aoeminor, 1242 skb->len); 1243 break; 1244 } 1245 if (skb_linearize(skb)) 1246 break; 1247 spin_lock_irq(&d->lock); 1248 ataid_complete(d, t, skb->data); 1249 spin_unlock_irq(&d->lock); 1250 break; 1251 default: 1252 pr_info("aoe: unrecognized ata command %2.2Xh for %d.%d\n", 1253 ahout->cmdstat, 1254 be16_to_cpu(get_unaligned(&hin->major)), 1255 hin->minor); 1256 } 1257 out: 1258 spin_lock_irq(&d->lock); 1259 if (t->taint > 0 1260 && --t->taint > 0 1261 && t->nout_probes == 0) { 1262 count_targets(d, &untainted); 1263 if (untainted > 0) { 1264 probe(t); 1265 t->nout_probes++; 1266 } 1267 } 1268 1269 aoe_freetframe(f); 1270 1271 if (buf && --buf->nframesout == 0 && buf->resid == 0) 1272 aoe_end_buf(d, buf); 1273 1274 spin_unlock_irq(&d->lock); 1275 aoedev_put(d); 1276 dev_kfree_skb(skb); 1277 } 1278 1279 /* Enters with iocq.lock held. 1280 * Returns true iff responses needing processing remain. 1281 */ 1282 static int 1283 ktio(void) 1284 { 1285 struct frame *f; 1286 struct list_head *pos; 1287 int i; 1288 1289 for (i = 0; ; ++i) { 1290 if (i == MAXIOC) 1291 return 1; 1292 if (list_empty(&iocq.head)) 1293 return 0; 1294 pos = iocq.head.next; 1295 list_del(pos); 1296 spin_unlock_irq(&iocq.lock); 1297 f = list_entry(pos, struct frame, head); 1298 ktiocomplete(f); 1299 spin_lock_irq(&iocq.lock); 1300 } 1301 } 1302 1303 static int 1304 kthread(void *vp) 1305 { 1306 struct ktstate *k; 1307 DECLARE_WAITQUEUE(wait, current); 1308 int more; 1309 1310 k = vp; 1311 current->flags |= PF_NOFREEZE; 1312 set_user_nice(current, -10); 1313 complete(&k->rendez); /* tell spawner we're running */ 1314 do { 1315 spin_lock_irq(k->lock); 1316 more = k->fn(); 1317 if (!more) { 1318 add_wait_queue(k->waitq, &wait); 1319 __set_current_state(TASK_INTERRUPTIBLE); 1320 } 1321 spin_unlock_irq(k->lock); 1322 if (!more) { 1323 schedule(); 1324 remove_wait_queue(k->waitq, &wait); 1325 } else 1326 cond_resched(); 1327 } while (!kthread_should_stop()); 1328 complete(&k->rendez); /* tell spawner we're stopping */ 1329 return 0; 1330 } 1331 1332 void 1333 aoe_ktstop(struct ktstate *k) 1334 { 1335 kthread_stop(k->task); 1336 wait_for_completion(&k->rendez); 1337 } 1338 1339 int 1340 aoe_ktstart(struct ktstate *k) 1341 { 1342 struct task_struct *task; 1343 1344 init_completion(&k->rendez); 1345 task = kthread_run(kthread, k, k->name); 1346 if (task == NULL || IS_ERR(task)) 1347 return -ENOMEM; 1348 k->task = task; 1349 wait_for_completion(&k->rendez); /* allow kthread to start */ 1350 init_completion(&k->rendez); /* for waiting for exit later */ 1351 return 0; 1352 } 1353 1354 /* pass it off to kthreads for processing */ 1355 static void 1356 ktcomplete(struct frame *f, struct sk_buff *skb) 1357 { 1358 ulong flags; 1359 1360 f->r_skb = skb; 1361 spin_lock_irqsave(&iocq.lock, flags); 1362 list_add_tail(&f->head, &iocq.head); 1363 spin_unlock_irqrestore(&iocq.lock, flags); 1364 wake_up(&ktiowq); 1365 } 1366 1367 struct sk_buff * 1368 aoecmd_ata_rsp(struct sk_buff *skb) 1369 { 1370 struct aoedev *d; 1371 struct aoe_hdr *h; 1372 struct frame *f; 1373 u32 n; 1374 ulong flags; 1375 char ebuf[128]; 1376 u16 aoemajor; 1377 1378 h = (struct aoe_hdr *) skb->data; 1379 aoemajor = be16_to_cpu(get_unaligned(&h->major)); 1380 d = aoedev_by_aoeaddr(aoemajor, h->minor, 0); 1381 if (d == NULL) { 1382 snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response " 1383 "for unknown device %d.%d\n", 1384 aoemajor, h->minor); 1385 aoechr_error(ebuf); 1386 return skb; 1387 } 1388 1389 spin_lock_irqsave(&d->lock, flags); 1390 1391 n = be32_to_cpu(get_unaligned(&h->tag)); 1392 f = getframe(d, n); 1393 if (f) { 1394 calc_rttavg(d, f->t, tsince_hr(f)); 1395 f->t->nout--; 1396 if (f->flags & FFL_PROBE) 1397 f->t->nout_probes--; 1398 } else { 1399 f = getframe_deferred(d, n); 1400 if (f) { 1401 calc_rttavg(d, NULL, tsince_hr(f)); 1402 } else { 1403 calc_rttavg(d, NULL, tsince(n)); 1404 spin_unlock_irqrestore(&d->lock, flags); 1405 aoedev_put(d); 1406 snprintf(ebuf, sizeof(ebuf), 1407 "%15s e%d.%d tag=%08x@%08lx s=%pm d=%pm\n", 1408 "unexpected rsp", 1409 get_unaligned_be16(&h->major), 1410 h->minor, 1411 get_unaligned_be32(&h->tag), 1412 jiffies, 1413 h->src, 1414 h->dst); 1415 aoechr_error(ebuf); 1416 return skb; 1417 } 1418 } 1419 aoecmd_work(d); 1420 1421 spin_unlock_irqrestore(&d->lock, flags); 1422 1423 ktcomplete(f, skb); 1424 1425 /* 1426 * Note here that we do not perform an aoedev_put, as we are 1427 * leaving this reference for the ktio to release. 1428 */ 1429 return NULL; 1430 } 1431 1432 void 1433 aoecmd_cfg(ushort aoemajor, unsigned char aoeminor) 1434 { 1435 struct sk_buff_head queue; 1436 1437 __skb_queue_head_init(&queue); 1438 aoecmd_cfg_pkts(aoemajor, aoeminor, &queue); 1439 aoenet_xmit(&queue); 1440 } 1441 1442 struct sk_buff * 1443 aoecmd_ata_id(struct aoedev *d) 1444 { 1445 struct aoe_hdr *h; 1446 struct aoe_atahdr *ah; 1447 struct frame *f; 1448 struct sk_buff *skb; 1449 struct aoetgt *t; 1450 1451 f = newframe(d); 1452 if (f == NULL) 1453 return NULL; 1454 1455 t = *d->tgt; 1456 1457 /* initialize the headers & frame */ 1458 skb = f->skb; 1459 h = (struct aoe_hdr *) skb_mac_header(skb); 1460 ah = (struct aoe_atahdr *) (h+1); 1461 skb_put(skb, sizeof *h + sizeof *ah); 1462 memset(h, 0, skb->len); 1463 f->tag = aoehdr_atainit(d, t, h); 1464 fhash(f); 1465 t->nout++; 1466 f->waited = 0; 1467 f->waited_total = 0; 1468 1469 /* set up ata header */ 1470 ah->scnt = 1; 1471 ah->cmdstat = ATA_CMD_ID_ATA; 1472 ah->lba3 = 0xa0; 1473 1474 skb->dev = t->ifp->nd; 1475 1476 d->rttavg = RTTAVG_INIT; 1477 d->rttdev = RTTDEV_INIT; 1478 d->timer.function = rexmit_timer; 1479 1480 skb = skb_clone(skb, GFP_ATOMIC); 1481 if (skb) { 1482 do_gettimeofday(&f->sent); 1483 f->sent_jiffs = (u32) jiffies; 1484 } 1485 1486 return skb; 1487 } 1488 1489 static struct aoetgt ** 1490 grow_targets(struct aoedev *d) 1491 { 1492 ulong oldn, newn; 1493 struct aoetgt **tt; 1494 1495 oldn = d->ntargets; 1496 newn = oldn * 2; 1497 tt = kcalloc(newn, sizeof(*d->targets), GFP_ATOMIC); 1498 if (!tt) 1499 return NULL; 1500 memmove(tt, d->targets, sizeof(*d->targets) * oldn); 1501 d->tgt = tt + (d->tgt - d->targets); 1502 kfree(d->targets); 1503 d->targets = tt; 1504 d->ntargets = newn; 1505 1506 return &d->targets[oldn]; 1507 } 1508 1509 static struct aoetgt * 1510 addtgt(struct aoedev *d, char *addr, ulong nframes) 1511 { 1512 struct aoetgt *t, **tt, **te; 1513 1514 tt = d->targets; 1515 te = tt + d->ntargets; 1516 for (; tt < te && *tt; tt++) 1517 ; 1518 1519 if (tt == te) { 1520 tt = grow_targets(d); 1521 if (!tt) 1522 goto nomem; 1523 } 1524 t = kzalloc(sizeof(*t), GFP_ATOMIC); 1525 if (!t) 1526 goto nomem; 1527 t->nframes = nframes; 1528 t->d = d; 1529 memcpy(t->addr, addr, sizeof t->addr); 1530 t->ifp = t->ifs; 1531 aoecmd_wreset(t); 1532 t->maxout = t->nframes / 2; 1533 INIT_LIST_HEAD(&t->ffree); 1534 return *tt = t; 1535 1536 nomem: 1537 pr_info("aoe: cannot allocate memory to add target\n"); 1538 return NULL; 1539 } 1540 1541 static void 1542 setdbcnt(struct aoedev *d) 1543 { 1544 struct aoetgt **t, **e; 1545 int bcnt = 0; 1546 1547 t = d->targets; 1548 e = t + d->ntargets; 1549 for (; t < e && *t; t++) 1550 if (bcnt == 0 || bcnt > (*t)->minbcnt) 1551 bcnt = (*t)->minbcnt; 1552 if (bcnt != d->maxbcnt) { 1553 d->maxbcnt = bcnt; 1554 pr_info("aoe: e%ld.%d: setting %d byte data frames\n", 1555 d->aoemajor, d->aoeminor, bcnt); 1556 } 1557 } 1558 1559 static void 1560 setifbcnt(struct aoetgt *t, struct net_device *nd, int bcnt) 1561 { 1562 struct aoedev *d; 1563 struct aoeif *p, *e; 1564 int minbcnt; 1565 1566 d = t->d; 1567 minbcnt = bcnt; 1568 p = t->ifs; 1569 e = p + NAOEIFS; 1570 for (; p < e; p++) { 1571 if (p->nd == NULL) 1572 break; /* end of the valid interfaces */ 1573 if (p->nd == nd) { 1574 p->bcnt = bcnt; /* we're updating */ 1575 nd = NULL; 1576 } else if (minbcnt > p->bcnt) 1577 minbcnt = p->bcnt; /* find the min interface */ 1578 } 1579 if (nd) { 1580 if (p == e) { 1581 pr_err("aoe: device setifbcnt failure; too many interfaces.\n"); 1582 return; 1583 } 1584 dev_hold(nd); 1585 p->nd = nd; 1586 p->bcnt = bcnt; 1587 } 1588 t->minbcnt = minbcnt; 1589 setdbcnt(d); 1590 } 1591 1592 void 1593 aoecmd_cfg_rsp(struct sk_buff *skb) 1594 { 1595 struct aoedev *d; 1596 struct aoe_hdr *h; 1597 struct aoe_cfghdr *ch; 1598 struct aoetgt *t; 1599 ulong flags, aoemajor; 1600 struct sk_buff *sl; 1601 struct sk_buff_head queue; 1602 u16 n; 1603 1604 sl = NULL; 1605 h = (struct aoe_hdr *) skb_mac_header(skb); 1606 ch = (struct aoe_cfghdr *) (h+1); 1607 1608 /* 1609 * Enough people have their dip switches set backwards to 1610 * warrant a loud message for this special case. 1611 */ 1612 aoemajor = get_unaligned_be16(&h->major); 1613 if (aoemajor == 0xfff) { 1614 printk(KERN_ERR "aoe: Warning: shelf address is all ones. " 1615 "Check shelf dip switches.\n"); 1616 return; 1617 } 1618 if (aoemajor == 0xffff) { 1619 pr_info("aoe: e%ld.%d: broadcast shelf number invalid\n", 1620 aoemajor, (int) h->minor); 1621 return; 1622 } 1623 if (h->minor == 0xff) { 1624 pr_info("aoe: e%ld.%d: broadcast slot number invalid\n", 1625 aoemajor, (int) h->minor); 1626 return; 1627 } 1628 1629 n = be16_to_cpu(ch->bufcnt); 1630 if (n > aoe_maxout) /* keep it reasonable */ 1631 n = aoe_maxout; 1632 1633 d = aoedev_by_aoeaddr(aoemajor, h->minor, 1); 1634 if (d == NULL) { 1635 pr_info("aoe: device allocation failure\n"); 1636 return; 1637 } 1638 1639 spin_lock_irqsave(&d->lock, flags); 1640 1641 t = gettgt(d, h->src); 1642 if (t) { 1643 t->nframes = n; 1644 if (n < t->maxout) 1645 aoecmd_wreset(t); 1646 } else { 1647 t = addtgt(d, h->src, n); 1648 if (!t) 1649 goto bail; 1650 } 1651 n = skb->dev->mtu; 1652 n -= sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr); 1653 n /= 512; 1654 if (n > ch->scnt) 1655 n = ch->scnt; 1656 n = n ? n * 512 : DEFAULTBCNT; 1657 setifbcnt(t, skb->dev, n); 1658 1659 /* don't change users' perspective */ 1660 if (d->nopen == 0) { 1661 d->fw_ver = be16_to_cpu(ch->fwver); 1662 sl = aoecmd_ata_id(d); 1663 } 1664 bail: 1665 spin_unlock_irqrestore(&d->lock, flags); 1666 aoedev_put(d); 1667 if (sl) { 1668 __skb_queue_head_init(&queue); 1669 __skb_queue_tail(&queue, sl); 1670 aoenet_xmit(&queue); 1671 } 1672 } 1673 1674 void 1675 aoecmd_wreset(struct aoetgt *t) 1676 { 1677 t->maxout = 1; 1678 t->ssthresh = t->nframes / 2; 1679 t->next_cwnd = t->nframes; 1680 } 1681 1682 void 1683 aoecmd_cleanslate(struct aoedev *d) 1684 { 1685 struct aoetgt **t, **te; 1686 1687 d->rttavg = RTTAVG_INIT; 1688 d->rttdev = RTTDEV_INIT; 1689 d->maxbcnt = 0; 1690 1691 t = d->targets; 1692 te = t + d->ntargets; 1693 for (; t < te && *t; t++) 1694 aoecmd_wreset(*t); 1695 } 1696 1697 void 1698 aoe_failbuf(struct aoedev *d, struct buf *buf) 1699 { 1700 if (buf == NULL) 1701 return; 1702 buf->resid = 0; 1703 clear_bit(BIO_UPTODATE, &buf->bio->bi_flags); 1704 if (buf->nframesout == 0) 1705 aoe_end_buf(d, buf); 1706 } 1707 1708 void 1709 aoe_flush_iocq(void) 1710 { 1711 struct frame *f; 1712 struct aoedev *d; 1713 LIST_HEAD(flist); 1714 struct list_head *pos; 1715 struct sk_buff *skb; 1716 ulong flags; 1717 1718 spin_lock_irqsave(&iocq.lock, flags); 1719 list_splice_init(&iocq.head, &flist); 1720 spin_unlock_irqrestore(&iocq.lock, flags); 1721 while (!list_empty(&flist)) { 1722 pos = flist.next; 1723 list_del(pos); 1724 f = list_entry(pos, struct frame, head); 1725 d = f->t->d; 1726 skb = f->r_skb; 1727 spin_lock_irqsave(&d->lock, flags); 1728 if (f->buf) { 1729 f->buf->nframesout--; 1730 aoe_failbuf(d, f->buf); 1731 } 1732 aoe_freetframe(f); 1733 spin_unlock_irqrestore(&d->lock, flags); 1734 dev_kfree_skb(skb); 1735 aoedev_put(d); 1736 } 1737 } 1738 1739 int __init 1740 aoecmd_init(void) 1741 { 1742 void *p; 1743 1744 /* get_zeroed_page returns page with ref count 1 */ 1745 p = (void *) get_zeroed_page(GFP_KERNEL | __GFP_REPEAT); 1746 if (!p) 1747 return -ENOMEM; 1748 empty_page = virt_to_page(p); 1749 1750 INIT_LIST_HEAD(&iocq.head); 1751 spin_lock_init(&iocq.lock); 1752 init_waitqueue_head(&ktiowq); 1753 kts.name = "aoe_ktio"; 1754 kts.fn = ktio; 1755 kts.waitq = &ktiowq; 1756 kts.lock = &iocq.lock; 1757 return aoe_ktstart(&kts); 1758 } 1759 1760 void 1761 aoecmd_exit(void) 1762 { 1763 aoe_ktstop(&kts); 1764 aoe_flush_iocq(); 1765 1766 free_page((unsigned long) page_address(empty_page)); 1767 empty_page = NULL; 1768 } 1769