1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2002 Poul-Henning Kamp 5 * Copyright (c) 2002 Networks Associates Technology, Inc. 6 * Copyright (c) 2013 The FreeBSD Foundation 7 * All rights reserved. 8 * 9 * This software was developed for the FreeBSD Project by Poul-Henning Kamp 10 * and NAI Labs, the Security Research Division of Network Associates, Inc. 11 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 12 * DARPA CHATS research program. 13 * 14 * Portions of this software were developed by Konstantin Belousov 15 * under sponsorship from the FreeBSD Foundation. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions 19 * are met: 20 * 1. Redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer. 22 * 2. Redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution. 25 * 3. The names of the authors may not be used to endorse or promote 26 * products derived from this software without specific prior written 27 * permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/malloc.h> 46 #include <sys/bio.h> 47 #include <sys/ktr.h> 48 #include <sys/proc.h> 49 #include <sys/sbuf.h> 50 #include <sys/stack.h> 51 #include <sys/sysctl.h> 52 #include <sys/vmem.h> 53 #include <machine/stack.h> 54 #include <machine/stdarg.h> 55 56 #include <sys/errno.h> 57 #include <geom/geom.h> 58 #include <geom/geom_int.h> 59 #include <sys/devicestat.h> 60 61 #include <vm/uma.h> 62 #include <vm/vm.h> 63 #include <vm/vm_param.h> 64 #include <vm/vm_kern.h> 65 #include <vm/vm_page.h> 66 #include <vm/vm_object.h> 67 #include <vm/vm_extern.h> 68 #include <vm/vm_map.h> 69 70 #define KTR_GEOM_ENABLED \ 71 ((KTR_COMPILE & KTR_GEOM) != 0 && (ktr_mask & KTR_GEOM) != 0) 72 73 static int g_io_transient_map_bio(struct bio *bp); 74 75 static struct g_bioq g_bio_run_down; 76 static struct g_bioq g_bio_run_up; 77 78 /* 79 * Pace is a hint that we've had some trouble recently allocating 80 * bios, so we should back off trying to send I/O down the stack 81 * a bit to let the problem resolve. When pacing, we also turn 82 * off direct dispatch to also reduce memory pressure from I/Os 83 * there, at the expxense of some added latency while the memory 84 * pressures exist. See g_io_schedule_down() for more details 85 * and limitations. 86 */ 87 static volatile u_int __read_mostly pace; 88 89 static uma_zone_t __read_mostly biozone; 90 91 #include <machine/atomic.h> 92 93 static void 94 g_bioq_lock(struct g_bioq *bq) 95 { 96 97 mtx_lock(&bq->bio_queue_lock); 98 } 99 100 static void 101 g_bioq_unlock(struct g_bioq *bq) 102 { 103 104 mtx_unlock(&bq->bio_queue_lock); 105 } 106 107 #if 0 108 static void 109 g_bioq_destroy(struct g_bioq *bq) 110 { 111 112 mtx_destroy(&bq->bio_queue_lock); 113 } 114 #endif 115 116 static void 117 g_bioq_init(struct g_bioq *bq) 118 { 119 120 TAILQ_INIT(&bq->bio_queue); 121 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 122 } 123 124 static struct bio * 125 g_bioq_first(struct g_bioq *bq) 126 { 127 struct bio *bp; 128 129 bp = TAILQ_FIRST(&bq->bio_queue); 130 if (bp != NULL) { 131 KASSERT((bp->bio_flags & BIO_ONQUEUE), 132 ("Bio not on queue bp=%p target %p", bp, bq)); 133 bp->bio_flags &= ~BIO_ONQUEUE; 134 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 135 bq->bio_queue_length--; 136 } 137 return (bp); 138 } 139 140 struct bio * 141 g_new_bio(void) 142 { 143 struct bio *bp; 144 145 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 146 #ifdef KTR 147 if (KTR_GEOM_ENABLED) { 148 struct stack st; 149 150 CTR1(KTR_GEOM, "g_new_bio(): %p", bp); 151 stack_save(&st); 152 CTRSTACK(KTR_GEOM, &st, 3); 153 } 154 #endif 155 return (bp); 156 } 157 158 struct bio * 159 g_alloc_bio(void) 160 { 161 struct bio *bp; 162 163 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); 164 #ifdef KTR 165 if (KTR_GEOM_ENABLED) { 166 struct stack st; 167 168 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp); 169 stack_save(&st); 170 CTRSTACK(KTR_GEOM, &st, 3); 171 } 172 #endif 173 return (bp); 174 } 175 176 void 177 g_destroy_bio(struct bio *bp) 178 { 179 #ifdef KTR 180 if (KTR_GEOM_ENABLED) { 181 struct stack st; 182 183 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp); 184 stack_save(&st); 185 CTRSTACK(KTR_GEOM, &st, 3); 186 } 187 #endif 188 uma_zfree(biozone, bp); 189 } 190 191 struct bio * 192 g_clone_bio(struct bio *bp) 193 { 194 struct bio *bp2; 195 196 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 197 if (bp2 != NULL) { 198 bp2->bio_parent = bp; 199 bp2->bio_cmd = bp->bio_cmd; 200 /* 201 * BIO_ORDERED flag may be used by disk drivers to enforce 202 * ordering restrictions, so this flag needs to be cloned. 203 * BIO_UNMAPPED, BIO_VLIST, and BIO_SWAP should be inherited, 204 * to properly indicate which way the buffer is passed. 205 * Other bio flags are not suitable for cloning. 206 */ 207 bp2->bio_flags = bp->bio_flags & 208 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST | BIO_SWAP); 209 bp2->bio_length = bp->bio_length; 210 bp2->bio_offset = bp->bio_offset; 211 bp2->bio_data = bp->bio_data; 212 bp2->bio_ma = bp->bio_ma; 213 bp2->bio_ma_n = bp->bio_ma_n; 214 bp2->bio_ma_offset = bp->bio_ma_offset; 215 bp2->bio_attribute = bp->bio_attribute; 216 if (bp->bio_cmd == BIO_ZONE) 217 bcopy(&bp->bio_zone, &bp2->bio_zone, 218 sizeof(bp->bio_zone)); 219 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 220 bp2->bio_track_bp = bp->bio_track_bp; 221 #endif 222 bp->bio_children++; 223 } 224 #ifdef KTR 225 if (KTR_GEOM_ENABLED) { 226 struct stack st; 227 228 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2); 229 stack_save(&st); 230 CTRSTACK(KTR_GEOM, &st, 3); 231 } 232 #endif 233 return(bp2); 234 } 235 236 struct bio * 237 g_duplicate_bio(struct bio *bp) 238 { 239 struct bio *bp2; 240 241 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO); 242 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST | BIO_SWAP); 243 bp2->bio_parent = bp; 244 bp2->bio_cmd = bp->bio_cmd; 245 bp2->bio_length = bp->bio_length; 246 bp2->bio_offset = bp->bio_offset; 247 bp2->bio_data = bp->bio_data; 248 bp2->bio_ma = bp->bio_ma; 249 bp2->bio_ma_n = bp->bio_ma_n; 250 bp2->bio_ma_offset = bp->bio_ma_offset; 251 bp2->bio_attribute = bp->bio_attribute; 252 bp->bio_children++; 253 #ifdef KTR 254 if (KTR_GEOM_ENABLED) { 255 struct stack st; 256 257 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2); 258 stack_save(&st); 259 CTRSTACK(KTR_GEOM, &st, 3); 260 } 261 #endif 262 return(bp2); 263 } 264 265 void 266 g_reset_bio(struct bio *bp) 267 { 268 269 bzero(bp, sizeof(*bp)); 270 } 271 272 void 273 g_io_init(void) 274 { 275 276 g_bioq_init(&g_bio_run_down); 277 g_bioq_init(&g_bio_run_up); 278 biozone = uma_zcreate("g_bio", sizeof (struct bio), 279 NULL, NULL, 280 NULL, NULL, 281 0, 0); 282 } 283 284 int 285 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 286 { 287 struct bio *bp; 288 int error; 289 290 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 291 bp = g_alloc_bio(); 292 bp->bio_cmd = BIO_GETATTR; 293 bp->bio_done = NULL; 294 bp->bio_attribute = attr; 295 bp->bio_length = *len; 296 bp->bio_data = ptr; 297 g_io_request(bp, cp); 298 error = biowait(bp, "ggetattr"); 299 *len = bp->bio_completed; 300 g_destroy_bio(bp); 301 return (error); 302 } 303 304 int 305 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp) 306 { 307 struct bio *bp; 308 int error; 309 310 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd); 311 bp = g_alloc_bio(); 312 bp->bio_cmd = BIO_ZONE; 313 bp->bio_done = NULL; 314 /* 315 * XXX KDM need to handle report zone data. 316 */ 317 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args)); 318 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) 319 bp->bio_length = 320 zone_args->zone_params.report.entries_allocated * 321 sizeof(struct disk_zone_rep_entry); 322 else 323 bp->bio_length = 0; 324 325 g_io_request(bp, cp); 326 error = biowait(bp, "gzone"); 327 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args)); 328 g_destroy_bio(bp); 329 return (error); 330 } 331 332 /* 333 * Send a BIO_SPEEDUP down the stack. This is used to tell the lower layers that 334 * the upper layers have detected a resource shortage. The lower layers are 335 * advised to stop delaying I/O that they might be holding for performance 336 * reasons and to schedule it (non-trims) or complete it successfully (trims) as 337 * quickly as it can. bio_length is the amount of the shortage. This call 338 * should be non-blocking. bio_resid is used to communicate back if the lower 339 * layers couldn't find bio_length worth of I/O to schedule or discard. A length 340 * of 0 means to do as much as you can (schedule the h/w queues full, discard 341 * all trims). flags are a hint from the upper layers to the lower layers what 342 * operation should be done. 343 */ 344 int 345 g_io_speedup(off_t shortage, u_int flags, size_t *resid, struct g_consumer *cp) 346 { 347 struct bio *bp; 348 int error; 349 350 KASSERT((flags & (BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE)) != 0, 351 ("Invalid flags passed to g_io_speedup: %#x", flags)); 352 g_trace(G_T_BIO, "bio_speedup(%s, %jd, %#x)", cp->provider->name, 353 (intmax_t)shortage, flags); 354 bp = g_new_bio(); 355 if (bp == NULL) 356 return (ENOMEM); 357 bp->bio_cmd = BIO_SPEEDUP; 358 bp->bio_length = shortage; 359 bp->bio_done = NULL; 360 bp->bio_flags |= flags; 361 g_io_request(bp, cp); 362 error = biowait(bp, "gflush"); 363 *resid = bp->bio_resid; 364 g_destroy_bio(bp); 365 return (error); 366 } 367 368 int 369 g_io_flush(struct g_consumer *cp) 370 { 371 struct bio *bp; 372 int error; 373 374 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name); 375 bp = g_alloc_bio(); 376 bp->bio_cmd = BIO_FLUSH; 377 bp->bio_flags |= BIO_ORDERED; 378 bp->bio_done = NULL; 379 bp->bio_attribute = NULL; 380 bp->bio_offset = cp->provider->mediasize; 381 bp->bio_length = 0; 382 bp->bio_data = NULL; 383 g_io_request(bp, cp); 384 error = biowait(bp, "gflush"); 385 g_destroy_bio(bp); 386 return (error); 387 } 388 389 static int 390 g_io_check(struct bio *bp) 391 { 392 struct g_consumer *cp; 393 struct g_provider *pp; 394 off_t excess; 395 int error; 396 397 biotrack(bp, __func__); 398 399 cp = bp->bio_from; 400 pp = bp->bio_to; 401 402 /* Fail if access counters dont allow the operation */ 403 switch(bp->bio_cmd) { 404 case BIO_READ: 405 case BIO_GETATTR: 406 if (cp->acr == 0) 407 return (EPERM); 408 break; 409 case BIO_WRITE: 410 case BIO_DELETE: 411 case BIO_SPEEDUP: 412 case BIO_FLUSH: 413 if (cp->acw == 0) 414 return (EPERM); 415 break; 416 case BIO_ZONE: 417 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) || 418 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) { 419 if (cp->acr == 0) 420 return (EPERM); 421 } else if (cp->acw == 0) 422 return (EPERM); 423 break; 424 default: 425 return (EPERM); 426 } 427 /* if provider is marked for error, don't disturb. */ 428 if (pp->error) 429 return (pp->error); 430 if (cp->flags & G_CF_ORPHAN) 431 return (ENXIO); 432 433 switch(bp->bio_cmd) { 434 case BIO_READ: 435 case BIO_WRITE: 436 case BIO_DELETE: 437 /* Zero sectorsize or mediasize is probably a lack of media. */ 438 if (pp->sectorsize == 0 || pp->mediasize == 0) 439 return (ENXIO); 440 /* Reject I/O not on sector boundary */ 441 if (bp->bio_offset % pp->sectorsize) 442 return (EINVAL); 443 /* Reject I/O not integral sector long */ 444 if (bp->bio_length % pp->sectorsize) 445 return (EINVAL); 446 /* Reject requests before or past the end of media. */ 447 if (bp->bio_offset < 0) 448 return (EIO); 449 if (bp->bio_offset > pp->mediasize) 450 return (EIO); 451 452 /* Truncate requests to the end of providers media. */ 453 excess = bp->bio_offset + bp->bio_length; 454 if (excess > bp->bio_to->mediasize) { 455 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 || 456 round_page(bp->bio_ma_offset + 457 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n, 458 ("excess bio %p too short", bp)); 459 excess -= bp->bio_to->mediasize; 460 bp->bio_length -= excess; 461 if ((bp->bio_flags & BIO_UNMAPPED) != 0) { 462 bp->bio_ma_n = round_page(bp->bio_ma_offset + 463 bp->bio_length) / PAGE_SIZE; 464 } 465 if (excess > 0) 466 CTR3(KTR_GEOM, "g_down truncated bio " 467 "%p provider %s by %d", bp, 468 bp->bio_to->name, excess); 469 } 470 471 /* Deliver zero length transfers right here. */ 472 if (bp->bio_length == 0) { 473 CTR2(KTR_GEOM, "g_down terminated 0-length " 474 "bp %p provider %s", bp, bp->bio_to->name); 475 return (0); 476 } 477 478 if ((bp->bio_flags & BIO_UNMAPPED) != 0 && 479 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 && 480 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) { 481 if ((error = g_io_transient_map_bio(bp)) >= 0) 482 return (error); 483 } 484 break; 485 default: 486 break; 487 } 488 return (EJUSTRETURN); 489 } 490 491 void 492 g_io_request(struct bio *bp, struct g_consumer *cp) 493 { 494 struct g_provider *pp; 495 int direct, error, first; 496 uint8_t cmd; 497 498 biotrack(bp, __func__); 499 500 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 501 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 502 pp = cp->provider; 503 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 504 #ifdef DIAGNOSTIC 505 KASSERT(bp->bio_driver1 == NULL, 506 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name)); 507 KASSERT(bp->bio_driver2 == NULL, 508 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name)); 509 KASSERT(bp->bio_pflags == 0, 510 ("bio_pflags used by the consumer (geom %s)", cp->geom->name)); 511 /* 512 * Remember consumer's private fields, so we can detect if they were 513 * modified by the provider. 514 */ 515 bp->_bio_caller1 = bp->bio_caller1; 516 bp->_bio_caller2 = bp->bio_caller2; 517 bp->_bio_cflags = bp->bio_cflags; 518 #endif 519 520 cmd = bp->bio_cmd; 521 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) { 522 KASSERT(bp->bio_data != NULL, 523 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd)); 524 } 525 if (cmd == BIO_DELETE || cmd == BIO_FLUSH || cmd == BIO_SPEEDUP) { 526 KASSERT(bp->bio_data == NULL, 527 ("non-NULL bp->data in g_io_request(cmd=%hu)", 528 bp->bio_cmd)); 529 } 530 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) { 531 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, 532 ("wrong offset %jd for sectorsize %u", 533 bp->bio_offset, cp->provider->sectorsize)); 534 KASSERT(bp->bio_length % cp->provider->sectorsize == 0, 535 ("wrong length %jd for sectorsize %u", 536 bp->bio_length, cp->provider->sectorsize)); 537 } 538 539 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 540 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 541 542 bp->bio_from = cp; 543 bp->bio_to = pp; 544 bp->bio_error = 0; 545 bp->bio_completed = 0; 546 547 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 548 ("Bio already on queue bp=%p", bp)); 549 550 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 551 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 552 binuptime(&bp->bio_t0); 553 else 554 getbinuptime(&bp->bio_t0); 555 if (g_collectstats & G_STATS_CONSUMERS) 556 devstat_start_transaction_bio_t0(cp->stat, bp); 557 if (g_collectstats & G_STATS_PROVIDERS) 558 devstat_start_transaction_bio_t0(pp->stat, bp); 559 #ifdef INVARIANTS 560 atomic_add_int(&cp->nstart, 1); 561 #endif 562 563 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 && 564 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 && 565 curthread != g_down_td && 566 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 || 567 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) && 568 pace == 0; 569 if (direct) { 570 /* Block direct execution if less then half of stack left. */ 571 size_t st, su; 572 GET_STACK_USAGE(st, su); 573 if (su * 2 > st) 574 direct = 0; 575 } 576 577 if (direct) { 578 error = g_io_check(bp); 579 if (error >= 0) { 580 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p " 581 "provider %s returned %d", bp, bp->bio_to->name, 582 error); 583 g_io_deliver(bp, error); 584 return; 585 } 586 bp->bio_to->geom->start(bp); 587 } else { 588 g_bioq_lock(&g_bio_run_down); 589 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue); 590 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue); 591 bp->bio_flags |= BIO_ONQUEUE; 592 g_bio_run_down.bio_queue_length++; 593 g_bioq_unlock(&g_bio_run_down); 594 /* Pass it on down. */ 595 if (first) 596 wakeup(&g_wait_down); 597 } 598 } 599 600 void 601 g_io_deliver(struct bio *bp, int error) 602 { 603 struct bintime now; 604 struct g_consumer *cp; 605 struct g_provider *pp; 606 struct mtx *mtxp; 607 int direct, first; 608 609 biotrack(bp, __func__); 610 611 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 612 pp = bp->bio_to; 613 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 614 cp = bp->bio_from; 615 if (cp == NULL) { 616 bp->bio_error = error; 617 bp->bio_done(bp); 618 return; 619 } 620 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 621 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 622 #ifdef DIAGNOSTIC 623 /* 624 * Some classes - GJournal in particular - can modify bio's 625 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO 626 * flag means it's an expected behaviour for that particular geom. 627 */ 628 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) { 629 KASSERT(bp->bio_caller1 == bp->_bio_caller1, 630 ("bio_caller1 used by the provider %s", pp->name)); 631 KASSERT(bp->bio_caller2 == bp->_bio_caller2, 632 ("bio_caller2 used by the provider %s", pp->name)); 633 KASSERT(bp->bio_cflags == bp->_bio_cflags, 634 ("bio_cflags used by the provider %s", pp->name)); 635 } 636 #endif 637 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 638 KASSERT(bp->bio_completed <= bp->bio_length, 639 ("bio_completed can't be greater than bio_length")); 640 641 g_trace(G_T_BIO, 642 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 643 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 644 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 645 646 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 647 ("Bio already on queue bp=%p", bp)); 648 649 /* 650 * XXX: next two doesn't belong here 651 */ 652 bp->bio_bcount = bp->bio_length; 653 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 654 655 direct = (pp->flags & G_PF_DIRECT_SEND) && 656 (cp->flags & G_CF_DIRECT_RECEIVE) && 657 curthread != g_up_td; 658 if (direct) { 659 /* Block direct execution if less then half of stack left. */ 660 size_t st, su; 661 GET_STACK_USAGE(st, su); 662 if (su * 2 > st) 663 direct = 0; 664 } 665 666 /* 667 * The statistics collection is lockless, as such, but we 668 * can not update one instance of the statistics from more 669 * than one thread at a time, so grab the lock first. 670 */ 671 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 672 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 673 binuptime(&now); 674 mtxp = mtx_pool_find(mtxpool_sleep, pp); 675 mtx_lock(mtxp); 676 if (g_collectstats & G_STATS_PROVIDERS) 677 devstat_end_transaction_bio_bt(pp->stat, bp, &now); 678 if (g_collectstats & G_STATS_CONSUMERS) 679 devstat_end_transaction_bio_bt(cp->stat, bp, &now); 680 #ifdef INVARIANTS 681 cp->nend++; 682 #endif 683 mtx_unlock(mtxp); 684 685 if (error != ENOMEM) { 686 bp->bio_error = error; 687 if (direct) { 688 biodone(bp); 689 } else { 690 g_bioq_lock(&g_bio_run_up); 691 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue); 692 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue); 693 bp->bio_flags |= BIO_ONQUEUE; 694 g_bio_run_up.bio_queue_length++; 695 g_bioq_unlock(&g_bio_run_up); 696 if (first) 697 wakeup(&g_wait_up); 698 } 699 return; 700 } 701 702 if (bootverbose) 703 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 704 bp->bio_children = 0; 705 bp->bio_inbed = 0; 706 bp->bio_driver1 = NULL; 707 bp->bio_driver2 = NULL; 708 bp->bio_pflags = 0; 709 g_io_request(bp, cp); 710 pace = 1; 711 return; 712 } 713 714 SYSCTL_DECL(_kern_geom); 715 716 static long transient_maps; 717 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD, 718 &transient_maps, 0, 719 "Total count of the transient mapping requests"); 720 u_int transient_map_retries = 10; 721 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW, 722 &transient_map_retries, 0, 723 "Max count of retries used before giving up on creating transient map"); 724 int transient_map_hard_failures; 725 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD, 726 &transient_map_hard_failures, 0, 727 "Failures to establish the transient mapping due to retry attempts " 728 "exhausted"); 729 int transient_map_soft_failures; 730 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD, 731 &transient_map_soft_failures, 0, 732 "Count of retried failures to establish the transient mapping"); 733 int inflight_transient_maps; 734 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD, 735 &inflight_transient_maps, 0, 736 "Current count of the active transient maps"); 737 738 static int 739 g_io_transient_map_bio(struct bio *bp) 740 { 741 vm_offset_t addr; 742 long size; 743 u_int retried; 744 745 KASSERT(unmapped_buf_allowed, ("unmapped disabled")); 746 747 size = round_page(bp->bio_ma_offset + bp->bio_length); 748 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp)); 749 addr = 0; 750 retried = 0; 751 atomic_add_long(&transient_maps, 1); 752 retry: 753 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) { 754 if (transient_map_retries != 0 && 755 retried >= transient_map_retries) { 756 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s", 757 bp, bp->bio_to->name); 758 atomic_add_int(&transient_map_hard_failures, 1); 759 return (EDEADLK/* XXXKIB */); 760 } else { 761 /* 762 * Naive attempt to quisce the I/O to get more 763 * in-flight requests completed and defragment 764 * the transient_arena. 765 */ 766 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d", 767 bp, bp->bio_to->name, retried); 768 pause("g_d_tra", hz / 10); 769 retried++; 770 atomic_add_int(&transient_map_soft_failures, 1); 771 goto retry; 772 } 773 } 774 atomic_add_int(&inflight_transient_maps, 1); 775 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size)); 776 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset; 777 bp->bio_flags |= BIO_TRANSIENT_MAPPING; 778 bp->bio_flags &= ~BIO_UNMAPPED; 779 return (EJUSTRETURN); 780 } 781 782 void 783 g_io_schedule_down(struct thread *tp __unused) 784 { 785 struct bio *bp; 786 int error; 787 788 for(;;) { 789 g_bioq_lock(&g_bio_run_down); 790 bp = g_bioq_first(&g_bio_run_down); 791 if (bp == NULL) { 792 CTR0(KTR_GEOM, "g_down going to sleep"); 793 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 794 PRIBIO | PDROP, "-", 0); 795 continue; 796 } 797 CTR0(KTR_GEOM, "g_down has work to do"); 798 g_bioq_unlock(&g_bio_run_down); 799 biotrack(bp, __func__); 800 if (pace != 0) { 801 /* 802 * There has been at least one memory allocation 803 * failure since the last I/O completed. Pause 1ms to 804 * give the system a chance to free up memory. We only 805 * do this once because a large number of allocations 806 * can fail in the direct dispatch case and there's no 807 * relationship between the number of these failures and 808 * the length of the outage. If there's still an outage, 809 * we'll pause again and again until it's 810 * resolved. Older versions paused longer and once per 811 * allocation failure. This was OK for a single threaded 812 * g_down, but with direct dispatch would lead to max of 813 * 10 IOPs for minutes at a time when transient memory 814 * issues prevented allocation for a batch of requests 815 * from the upper layers. 816 * 817 * XXX This pacing is really lame. It needs to be solved 818 * by other methods. This is OK only because the worst 819 * case scenario is so rare. In the worst case scenario 820 * all memory is tied up waiting for I/O to complete 821 * which can never happen since we can't allocate bios 822 * for that I/O. 823 */ 824 CTR0(KTR_GEOM, "g_down pacing self"); 825 pause("g_down", min(hz/1000, 1)); 826 pace = 0; 827 } 828 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp, 829 bp->bio_to->name); 830 error = g_io_check(bp); 831 if (error >= 0) { 832 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider " 833 "%s returned %d", bp, bp->bio_to->name, error); 834 g_io_deliver(bp, error); 835 continue; 836 } 837 THREAD_NO_SLEEPING(); 838 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld " 839 "len %ld", bp, bp->bio_to->name, bp->bio_offset, 840 bp->bio_length); 841 bp->bio_to->geom->start(bp); 842 THREAD_SLEEPING_OK(); 843 } 844 } 845 846 void 847 g_io_schedule_up(struct thread *tp __unused) 848 { 849 struct bio *bp; 850 851 for(;;) { 852 g_bioq_lock(&g_bio_run_up); 853 bp = g_bioq_first(&g_bio_run_up); 854 if (bp == NULL) { 855 CTR0(KTR_GEOM, "g_up going to sleep"); 856 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 857 PRIBIO | PDROP, "-", 0); 858 continue; 859 } 860 g_bioq_unlock(&g_bio_run_up); 861 THREAD_NO_SLEEPING(); 862 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off " 863 "%jd len %ld", bp, bp->bio_to->name, 864 bp->bio_offset, bp->bio_length); 865 biodone(bp); 866 THREAD_SLEEPING_OK(); 867 } 868 } 869 870 void * 871 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 872 { 873 struct bio *bp; 874 void *ptr; 875 int errorc; 876 877 KASSERT(length > 0 && length >= cp->provider->sectorsize && 878 length <= maxphys, ("g_read_data(): invalid length %jd", 879 (intmax_t)length)); 880 881 bp = g_alloc_bio(); 882 bp->bio_cmd = BIO_READ; 883 bp->bio_done = NULL; 884 bp->bio_offset = offset; 885 bp->bio_length = length; 886 ptr = g_malloc(length, M_WAITOK); 887 bp->bio_data = ptr; 888 g_io_request(bp, cp); 889 errorc = biowait(bp, "gread"); 890 if (errorc == 0 && bp->bio_completed != length) 891 errorc = EIO; 892 if (error != NULL) 893 *error = errorc; 894 g_destroy_bio(bp); 895 if (errorc) { 896 g_free(ptr); 897 ptr = NULL; 898 } 899 return (ptr); 900 } 901 902 /* 903 * A read function for use by ffs_sbget when used by GEOM-layer routines. 904 */ 905 int 906 g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size) 907 { 908 struct g_consumer *cp; 909 910 KASSERT(*bufp == NULL, 911 ("g_use_g_read_data: non-NULL *bufp %p\n", *bufp)); 912 913 cp = (struct g_consumer *)devfd; 914 /* 915 * Take care not to issue an invalid I/O request. The offset of 916 * the superblock candidate must be multiples of the provider's 917 * sector size, otherwise an FFS can't exist on the provider 918 * anyway. 919 */ 920 if (loc % cp->provider->sectorsize != 0) 921 return (ENOENT); 922 *bufp = g_read_data(cp, loc, size, NULL); 923 if (*bufp == NULL) 924 return (ENOENT); 925 return (0); 926 } 927 928 int 929 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 930 { 931 struct bio *bp; 932 int error; 933 934 KASSERT(length > 0 && length >= cp->provider->sectorsize && 935 length <= maxphys, ("g_write_data(): invalid length %jd", 936 (intmax_t)length)); 937 938 bp = g_alloc_bio(); 939 bp->bio_cmd = BIO_WRITE; 940 bp->bio_done = NULL; 941 bp->bio_offset = offset; 942 bp->bio_length = length; 943 bp->bio_data = ptr; 944 g_io_request(bp, cp); 945 error = biowait(bp, "gwrite"); 946 if (error == 0 && bp->bio_completed != length) 947 error = EIO; 948 g_destroy_bio(bp); 949 return (error); 950 } 951 952 /* 953 * A write function for use by ffs_sbput when used by GEOM-layer routines. 954 */ 955 int 956 g_use_g_write_data(void *devfd, off_t loc, void *buf, int size) 957 { 958 959 return (g_write_data((struct g_consumer *)devfd, loc, buf, size)); 960 } 961 962 int 963 g_delete_data(struct g_consumer *cp, off_t offset, off_t length) 964 { 965 struct bio *bp; 966 int error; 967 968 KASSERT(length > 0 && length >= cp->provider->sectorsize, 969 ("g_delete_data(): invalid length %jd", (intmax_t)length)); 970 971 bp = g_alloc_bio(); 972 bp->bio_cmd = BIO_DELETE; 973 bp->bio_done = NULL; 974 bp->bio_offset = offset; 975 bp->bio_length = length; 976 bp->bio_data = NULL; 977 g_io_request(bp, cp); 978 error = biowait(bp, "gdelete"); 979 if (error == 0 && bp->bio_completed != length) 980 error = EIO; 981 g_destroy_bio(bp); 982 return (error); 983 } 984 985 void 986 g_print_bio(const char *prefix, const struct bio *bp, const char *fmtsuffix, 987 ...) 988 { 989 #ifndef PRINTF_BUFR_SIZE 990 #define PRINTF_BUFR_SIZE 64 991 #endif 992 char bufr[PRINTF_BUFR_SIZE]; 993 struct sbuf sb, *sbp __unused; 994 va_list ap; 995 996 sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN); 997 KASSERT(sbp != NULL, ("sbuf_new misused?")); 998 999 sbuf_set_drain(&sb, sbuf_printf_drain, NULL); 1000 1001 sbuf_cat(&sb, prefix); 1002 g_format_bio(&sb, bp); 1003 1004 va_start(ap, fmtsuffix); 1005 sbuf_vprintf(&sb, fmtsuffix, ap); 1006 va_end(ap); 1007 1008 sbuf_nl_terminate(&sb); 1009 1010 sbuf_finish(&sb); 1011 sbuf_delete(&sb); 1012 } 1013 1014 void 1015 g_format_bio(struct sbuf *sb, const struct bio *bp) 1016 { 1017 const char *pname, *cmd = NULL; 1018 1019 if (bp->bio_to != NULL) 1020 pname = bp->bio_to->name; 1021 else if (bp->bio_parent != NULL && bp->bio_parent->bio_to != NULL) 1022 pname = bp->bio_parent->bio_to->name; 1023 else 1024 pname = "[unknown]"; 1025 1026 switch (bp->bio_cmd) { 1027 case BIO_GETATTR: 1028 cmd = "GETATTR"; 1029 sbuf_printf(sb, "%s[%s(attr=%s)]", pname, cmd, 1030 bp->bio_attribute); 1031 return; 1032 case BIO_FLUSH: 1033 cmd = "FLUSH"; 1034 sbuf_printf(sb, "%s[%s]", pname, cmd); 1035 return; 1036 case BIO_ZONE: { 1037 char *subcmd = NULL; 1038 cmd = "ZONE"; 1039 switch (bp->bio_zone.zone_cmd) { 1040 case DISK_ZONE_OPEN: 1041 subcmd = "OPEN"; 1042 break; 1043 case DISK_ZONE_CLOSE: 1044 subcmd = "CLOSE"; 1045 break; 1046 case DISK_ZONE_FINISH: 1047 subcmd = "FINISH"; 1048 break; 1049 case DISK_ZONE_RWP: 1050 subcmd = "RWP"; 1051 break; 1052 case DISK_ZONE_REPORT_ZONES: 1053 subcmd = "REPORT ZONES"; 1054 break; 1055 case DISK_ZONE_GET_PARAMS: 1056 subcmd = "GET PARAMS"; 1057 break; 1058 default: 1059 subcmd = "UNKNOWN"; 1060 break; 1061 } 1062 sbuf_printf(sb, "%s[%s,%s]", pname, cmd, subcmd); 1063 return; 1064 } 1065 case BIO_READ: 1066 cmd = "READ"; 1067 break; 1068 case BIO_WRITE: 1069 cmd = "WRITE"; 1070 break; 1071 case BIO_DELETE: 1072 cmd = "DELETE"; 1073 break; 1074 default: 1075 cmd = "UNKNOWN"; 1076 sbuf_printf(sb, "%s[%s()]", pname, cmd); 1077 return; 1078 } 1079 sbuf_printf(sb, "%s[%s(offset=%jd, length=%jd)]", pname, cmd, 1080 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 1081 } 1082