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 static u_long nomem_count; 79 static u_long pause_count; 80 81 /* 82 * Pace is a hint that we've had some trouble recently allocating 83 * bios, so we should back off trying to send I/O down the stack 84 * a bit to let the problem resolve. When pacing, we also turn 85 * off direct dispatch to also reduce memory pressure from I/Os 86 * there, at the expxense of some added latency while the memory 87 * pressures exist. See g_io_schedule_down() for more details 88 * and limitations. 89 */ 90 static volatile u_int __read_mostly pace; 91 92 static uma_zone_t __read_mostly biozone; 93 94 #include <machine/atomic.h> 95 96 static void 97 g_bioq_lock(struct g_bioq *bq) 98 { 99 100 mtx_lock(&bq->bio_queue_lock); 101 } 102 103 static void 104 g_bioq_unlock(struct g_bioq *bq) 105 { 106 107 mtx_unlock(&bq->bio_queue_lock); 108 } 109 110 #if 0 111 static void 112 g_bioq_destroy(struct g_bioq *bq) 113 { 114 115 mtx_destroy(&bq->bio_queue_lock); 116 } 117 #endif 118 119 static void 120 g_bioq_init(struct g_bioq *bq) 121 { 122 123 TAILQ_INIT(&bq->bio_queue); 124 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 125 } 126 127 static struct bio * 128 g_bioq_first(struct g_bioq *bq) 129 { 130 struct bio *bp; 131 132 bp = TAILQ_FIRST(&bq->bio_queue); 133 if (bp != NULL) { 134 KASSERT((bp->bio_flags & BIO_ONQUEUE), 135 ("Bio not on queue bp=%p target %p", bp, bq)); 136 bp->bio_flags &= ~BIO_ONQUEUE; 137 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 138 bq->bio_queue_length--; 139 } 140 return (bp); 141 } 142 143 struct bio * 144 g_new_bio(void) 145 { 146 struct bio *bp; 147 148 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 149 #ifdef KTR 150 if (KTR_GEOM_ENABLED) { 151 struct stack st; 152 153 CTR1(KTR_GEOM, "g_new_bio(): %p", bp); 154 stack_save(&st); 155 CTRSTACK(KTR_GEOM, &st, 3); 156 } 157 #endif 158 return (bp); 159 } 160 161 struct bio * 162 g_alloc_bio(void) 163 { 164 struct bio *bp; 165 166 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); 167 #ifdef KTR 168 if (KTR_GEOM_ENABLED) { 169 struct stack st; 170 171 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp); 172 stack_save(&st); 173 CTRSTACK(KTR_GEOM, &st, 3); 174 } 175 #endif 176 return (bp); 177 } 178 179 void 180 g_destroy_bio(struct bio *bp) 181 { 182 #ifdef KTR 183 if (KTR_GEOM_ENABLED) { 184 struct stack st; 185 186 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp); 187 stack_save(&st); 188 CTRSTACK(KTR_GEOM, &st, 3); 189 } 190 #endif 191 uma_zfree(biozone, bp); 192 } 193 194 struct bio * 195 g_clone_bio(struct bio *bp) 196 { 197 struct bio *bp2; 198 199 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 200 if (bp2 != NULL) { 201 bp2->bio_parent = bp; 202 bp2->bio_cmd = bp->bio_cmd; 203 /* 204 * BIO_ORDERED flag may be used by disk drivers to enforce 205 * ordering restrictions, so this flag needs to be cloned. 206 * BIO_UNMAPPED, BIO_VLIST, and BIO_SWAP should be inherited, 207 * to properly indicate which way the buffer is passed. 208 * Other bio flags are not suitable for cloning. 209 */ 210 bp2->bio_flags = bp->bio_flags & 211 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST | BIO_SWAP); 212 bp2->bio_length = bp->bio_length; 213 bp2->bio_offset = bp->bio_offset; 214 bp2->bio_data = bp->bio_data; 215 bp2->bio_ma = bp->bio_ma; 216 bp2->bio_ma_n = bp->bio_ma_n; 217 bp2->bio_ma_offset = bp->bio_ma_offset; 218 bp2->bio_attribute = bp->bio_attribute; 219 if (bp->bio_cmd == BIO_ZONE) 220 bcopy(&bp->bio_zone, &bp2->bio_zone, 221 sizeof(bp->bio_zone)); 222 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 223 bp2->bio_track_bp = bp->bio_track_bp; 224 #endif 225 bp->bio_children++; 226 } 227 #ifdef KTR 228 if (KTR_GEOM_ENABLED) { 229 struct stack st; 230 231 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2); 232 stack_save(&st); 233 CTRSTACK(KTR_GEOM, &st, 3); 234 } 235 #endif 236 return(bp2); 237 } 238 239 struct bio * 240 g_duplicate_bio(struct bio *bp) 241 { 242 struct bio *bp2; 243 244 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO); 245 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST | BIO_SWAP); 246 bp2->bio_parent = bp; 247 bp2->bio_cmd = bp->bio_cmd; 248 bp2->bio_length = bp->bio_length; 249 bp2->bio_offset = bp->bio_offset; 250 bp2->bio_data = bp->bio_data; 251 bp2->bio_ma = bp->bio_ma; 252 bp2->bio_ma_n = bp->bio_ma_n; 253 bp2->bio_ma_offset = bp->bio_ma_offset; 254 bp2->bio_attribute = bp->bio_attribute; 255 bp->bio_children++; 256 #ifdef KTR 257 if (KTR_GEOM_ENABLED) { 258 struct stack st; 259 260 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2); 261 stack_save(&st); 262 CTRSTACK(KTR_GEOM, &st, 3); 263 } 264 #endif 265 return(bp2); 266 } 267 268 void 269 g_reset_bio(struct bio *bp) 270 { 271 272 bzero(bp, sizeof(*bp)); 273 } 274 275 void 276 g_io_init(void) 277 { 278 279 g_bioq_init(&g_bio_run_down); 280 g_bioq_init(&g_bio_run_up); 281 biozone = uma_zcreate("g_bio", sizeof (struct bio), 282 NULL, NULL, 283 NULL, NULL, 284 0, 0); 285 } 286 287 int 288 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 289 { 290 struct bio *bp; 291 int error; 292 293 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 294 bp = g_alloc_bio(); 295 bp->bio_cmd = BIO_GETATTR; 296 bp->bio_done = NULL; 297 bp->bio_attribute = attr; 298 bp->bio_length = *len; 299 bp->bio_data = ptr; 300 g_io_request(bp, cp); 301 error = biowait(bp, "ggetattr"); 302 *len = bp->bio_completed; 303 g_destroy_bio(bp); 304 return (error); 305 } 306 307 int 308 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp) 309 { 310 struct bio *bp; 311 int error; 312 313 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd); 314 bp = g_alloc_bio(); 315 bp->bio_cmd = BIO_ZONE; 316 bp->bio_done = NULL; 317 /* 318 * XXX KDM need to handle report zone data. 319 */ 320 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args)); 321 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) 322 bp->bio_length = 323 zone_args->zone_params.report.entries_allocated * 324 sizeof(struct disk_zone_rep_entry); 325 else 326 bp->bio_length = 0; 327 328 g_io_request(bp, cp); 329 error = biowait(bp, "gzone"); 330 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args)); 331 g_destroy_bio(bp); 332 return (error); 333 } 334 335 /* 336 * Send a BIO_SPEEDUP down the stack. This is used to tell the lower layers that 337 * the upper layers have detected a resource shortage. The lower layers are 338 * advised to stop delaying I/O that they might be holding for performance 339 * reasons and to schedule it (non-trims) or complete it successfully (trims) as 340 * quickly as it can. bio_length is the amount of the shortage. This call 341 * should be non-blocking. bio_resid is used to communicate back if the lower 342 * layers couldn't find bio_length worth of I/O to schedule or discard. A length 343 * of 0 means to do as much as you can (schedule the h/w queues full, discard 344 * all trims). flags are a hint from the upper layers to the lower layers what 345 * operation should be done. 346 */ 347 int 348 g_io_speedup(off_t shortage, u_int flags, size_t *resid, struct g_consumer *cp) 349 { 350 struct bio *bp; 351 int error; 352 353 KASSERT((flags & (BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE)) != 0, 354 ("Invalid flags passed to g_io_speedup: %#x", flags)); 355 g_trace(G_T_BIO, "bio_speedup(%s, %jd, %#x)", cp->provider->name, 356 (intmax_t)shortage, flags); 357 bp = g_new_bio(); 358 if (bp == NULL) 359 return (ENOMEM); 360 bp->bio_cmd = BIO_SPEEDUP; 361 bp->bio_length = shortage; 362 bp->bio_done = NULL; 363 bp->bio_flags |= flags; 364 g_io_request(bp, cp); 365 error = biowait(bp, "gflush"); 366 *resid = bp->bio_resid; 367 g_destroy_bio(bp); 368 return (error); 369 } 370 371 int 372 g_io_flush(struct g_consumer *cp) 373 { 374 struct bio *bp; 375 int error; 376 377 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name); 378 bp = g_alloc_bio(); 379 bp->bio_cmd = BIO_FLUSH; 380 bp->bio_flags |= BIO_ORDERED; 381 bp->bio_done = NULL; 382 bp->bio_attribute = NULL; 383 bp->bio_offset = cp->provider->mediasize; 384 bp->bio_length = 0; 385 bp->bio_data = NULL; 386 g_io_request(bp, cp); 387 error = biowait(bp, "gflush"); 388 g_destroy_bio(bp); 389 return (error); 390 } 391 392 static int 393 g_io_check(struct bio *bp) 394 { 395 struct g_consumer *cp; 396 struct g_provider *pp; 397 off_t excess; 398 int error; 399 400 biotrack(bp, __func__); 401 402 cp = bp->bio_from; 403 pp = bp->bio_to; 404 405 /* Fail if access counters dont allow the operation */ 406 switch(bp->bio_cmd) { 407 case BIO_READ: 408 case BIO_GETATTR: 409 if (cp->acr == 0) 410 return (EPERM); 411 break; 412 case BIO_WRITE: 413 case BIO_DELETE: 414 case BIO_SPEEDUP: 415 case BIO_FLUSH: 416 if (cp->acw == 0) 417 return (EPERM); 418 break; 419 case BIO_ZONE: 420 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) || 421 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) { 422 if (cp->acr == 0) 423 return (EPERM); 424 } else if (cp->acw == 0) 425 return (EPERM); 426 break; 427 default: 428 return (EPERM); 429 } 430 /* if provider is marked for error, don't disturb. */ 431 if (pp->error) 432 return (pp->error); 433 if (cp->flags & G_CF_ORPHAN) 434 return (ENXIO); 435 436 switch(bp->bio_cmd) { 437 case BIO_READ: 438 case BIO_WRITE: 439 case BIO_DELETE: 440 /* Zero sectorsize or mediasize is probably a lack of media. */ 441 if (pp->sectorsize == 0 || pp->mediasize == 0) 442 return (ENXIO); 443 /* Reject I/O not on sector boundary */ 444 if (bp->bio_offset % pp->sectorsize) 445 return (EINVAL); 446 /* Reject I/O not integral sector long */ 447 if (bp->bio_length % pp->sectorsize) 448 return (EINVAL); 449 /* Reject requests before or past the end of media. */ 450 if (bp->bio_offset < 0) 451 return (EIO); 452 if (bp->bio_offset > pp->mediasize) 453 return (EIO); 454 455 /* Truncate requests to the end of providers media. */ 456 excess = bp->bio_offset + bp->bio_length; 457 if (excess > bp->bio_to->mediasize) { 458 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 || 459 round_page(bp->bio_ma_offset + 460 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n, 461 ("excess bio %p too short", bp)); 462 excess -= bp->bio_to->mediasize; 463 bp->bio_length -= excess; 464 if ((bp->bio_flags & BIO_UNMAPPED) != 0) { 465 bp->bio_ma_n = round_page(bp->bio_ma_offset + 466 bp->bio_length) / PAGE_SIZE; 467 } 468 if (excess > 0) 469 CTR3(KTR_GEOM, "g_down truncated bio " 470 "%p provider %s by %d", bp, 471 bp->bio_to->name, excess); 472 } 473 474 /* Deliver zero length transfers right here. */ 475 if (bp->bio_length == 0) { 476 CTR2(KTR_GEOM, "g_down terminated 0-length " 477 "bp %p provider %s", bp, bp->bio_to->name); 478 return (0); 479 } 480 481 if ((bp->bio_flags & BIO_UNMAPPED) != 0 && 482 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 && 483 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) { 484 if ((error = g_io_transient_map_bio(bp)) >= 0) 485 return (error); 486 } 487 break; 488 default: 489 break; 490 } 491 return (EJUSTRETURN); 492 } 493 494 void 495 g_io_request(struct bio *bp, struct g_consumer *cp) 496 { 497 struct g_provider *pp; 498 int direct, error, first; 499 uint8_t cmd; 500 501 biotrack(bp, __func__); 502 503 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 504 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 505 pp = cp->provider; 506 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 507 #ifdef DIAGNOSTIC 508 KASSERT(bp->bio_driver1 == NULL, 509 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name)); 510 KASSERT(bp->bio_driver2 == NULL, 511 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name)); 512 KASSERT(bp->bio_pflags == 0, 513 ("bio_pflags used by the consumer (geom %s)", cp->geom->name)); 514 /* 515 * Remember consumer's private fields, so we can detect if they were 516 * modified by the provider. 517 */ 518 bp->_bio_caller1 = bp->bio_caller1; 519 bp->_bio_caller2 = bp->bio_caller2; 520 bp->_bio_cflags = bp->bio_cflags; 521 #endif 522 523 cmd = bp->bio_cmd; 524 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) { 525 KASSERT(bp->bio_data != NULL, 526 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd)); 527 } 528 if (cmd == BIO_DELETE || cmd == BIO_FLUSH || cmd == BIO_SPEEDUP) { 529 KASSERT(bp->bio_data == NULL, 530 ("non-NULL bp->data in g_io_request(cmd=%hu)", 531 bp->bio_cmd)); 532 } 533 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) { 534 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, 535 ("wrong offset %jd for sectorsize %u", 536 bp->bio_offset, cp->provider->sectorsize)); 537 KASSERT(bp->bio_length % cp->provider->sectorsize == 0, 538 ("wrong length %jd for sectorsize %u", 539 bp->bio_length, cp->provider->sectorsize)); 540 } 541 542 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 543 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 544 545 bp->bio_from = cp; 546 bp->bio_to = pp; 547 bp->bio_error = 0; 548 bp->bio_completed = 0; 549 550 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 551 ("Bio already on queue bp=%p", bp)); 552 553 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 554 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 555 binuptime(&bp->bio_t0); 556 else 557 getbinuptime(&bp->bio_t0); 558 if (g_collectstats & G_STATS_CONSUMERS) 559 devstat_start_transaction_bio_t0(cp->stat, bp); 560 if (g_collectstats & G_STATS_PROVIDERS) 561 devstat_start_transaction_bio_t0(pp->stat, bp); 562 #ifdef INVARIANTS 563 atomic_add_int(&cp->nstart, 1); 564 #endif 565 566 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 && 567 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 && 568 curthread != g_down_td && 569 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 || 570 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) && 571 pace == 0; 572 if (direct) { 573 /* Block direct execution if less then half of stack left. */ 574 size_t st, su; 575 GET_STACK_USAGE(st, su); 576 if (su * 2 > st) 577 direct = 0; 578 } 579 580 if (direct) { 581 error = g_io_check(bp); 582 if (error >= 0) { 583 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p " 584 "provider %s returned %d", bp, bp->bio_to->name, 585 error); 586 g_io_deliver(bp, error); 587 return; 588 } 589 bp->bio_to->geom->start(bp); 590 } else { 591 g_bioq_lock(&g_bio_run_down); 592 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue); 593 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue); 594 bp->bio_flags |= BIO_ONQUEUE; 595 g_bio_run_down.bio_queue_length++; 596 g_bioq_unlock(&g_bio_run_down); 597 /* Pass it on down. */ 598 if (first) 599 wakeup(&g_wait_down); 600 } 601 } 602 603 void 604 g_io_deliver(struct bio *bp, int error) 605 { 606 struct bintime now; 607 struct g_consumer *cp; 608 struct g_provider *pp; 609 struct mtx *mtxp; 610 int direct, first; 611 612 biotrack(bp, __func__); 613 614 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 615 pp = bp->bio_to; 616 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 617 cp = bp->bio_from; 618 if (cp == NULL) { 619 bp->bio_error = error; 620 bp->bio_done(bp); 621 return; 622 } 623 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 624 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 625 #ifdef DIAGNOSTIC 626 /* 627 * Some classes - GJournal in particular - can modify bio's 628 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO 629 * flag means it's an expected behaviour for that particular geom. 630 */ 631 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) { 632 KASSERT(bp->bio_caller1 == bp->_bio_caller1, 633 ("bio_caller1 used by the provider %s", pp->name)); 634 KASSERT(bp->bio_caller2 == bp->_bio_caller2, 635 ("bio_caller2 used by the provider %s", pp->name)); 636 KASSERT(bp->bio_cflags == bp->_bio_cflags, 637 ("bio_cflags used by the provider %s", pp->name)); 638 } 639 #endif 640 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 641 KASSERT(bp->bio_completed <= bp->bio_length, 642 ("bio_completed can't be greater than bio_length")); 643 644 g_trace(G_T_BIO, 645 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 646 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 647 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 648 649 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 650 ("Bio already on queue bp=%p", bp)); 651 652 /* 653 * XXX: next two doesn't belong here 654 */ 655 bp->bio_bcount = bp->bio_length; 656 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 657 658 direct = (pp->flags & G_PF_DIRECT_SEND) && 659 (cp->flags & G_CF_DIRECT_RECEIVE) && 660 curthread != g_up_td; 661 if (direct) { 662 /* Block direct execution if less then half of stack left. */ 663 size_t st, su; 664 GET_STACK_USAGE(st, su); 665 if (su * 2 > st) 666 direct = 0; 667 } 668 669 /* 670 * The statistics collection is lockless, as such, but we 671 * can not update one instance of the statistics from more 672 * than one thread at a time, so grab the lock first. 673 */ 674 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 675 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 676 binuptime(&now); 677 mtxp = mtx_pool_find(mtxpool_sleep, pp); 678 mtx_lock(mtxp); 679 if (g_collectstats & G_STATS_PROVIDERS) 680 devstat_end_transaction_bio_bt(pp->stat, bp, &now); 681 if (g_collectstats & G_STATS_CONSUMERS) 682 devstat_end_transaction_bio_bt(cp->stat, bp, &now); 683 #ifdef INVARIANTS 684 cp->nend++; 685 #endif 686 mtx_unlock(mtxp); 687 688 if (error != ENOMEM) { 689 bp->bio_error = error; 690 if (direct) { 691 biodone(bp); 692 } else { 693 g_bioq_lock(&g_bio_run_up); 694 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue); 695 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue); 696 bp->bio_flags |= BIO_ONQUEUE; 697 g_bio_run_up.bio_queue_length++; 698 g_bioq_unlock(&g_bio_run_up); 699 if (first) 700 wakeup(&g_wait_up); 701 } 702 return; 703 } 704 705 if (bootverbose) 706 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 707 atomic_add_long(&nomem_count, 1); /* Rare event, but no locks held */ 708 bp->bio_children = 0; 709 bp->bio_inbed = 0; 710 bp->bio_driver1 = NULL; 711 bp->bio_driver2 = NULL; 712 bp->bio_pflags = 0; 713 g_io_request(bp, cp); 714 pace = 1; 715 return; 716 } 717 718 SYSCTL_DECL(_kern_geom); 719 720 static long transient_maps; 721 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD, 722 &transient_maps, 0, 723 "Total count of the transient mapping requests"); 724 u_int transient_map_retries = 10; 725 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW, 726 &transient_map_retries, 0, 727 "Max count of retries used before giving up on creating transient map"); 728 int transient_map_hard_failures; 729 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD, 730 &transient_map_hard_failures, 0, 731 "Failures to establish the transient mapping due to retry attempts " 732 "exhausted"); 733 int transient_map_soft_failures; 734 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD, 735 &transient_map_soft_failures, 0, 736 "Count of retried failures to establish the transient mapping"); 737 int inflight_transient_maps; 738 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD, 739 &inflight_transient_maps, 0, 740 "Current count of the active transient maps"); 741 SYSCTL_ULONG(_kern_geom, OID_AUTO, nomem_count, CTLFLAG_RD, 742 &nomem_count, 0, 743 "Total count of requests completed with status of ENOMEM"); 744 SYSCTL_ULONG(_kern_geom, OID_AUTO, pause_count, CTLFLAG_RD, 745 &pause_count, 0, 746 "Total count of requests stalled due to low memory in g_down"); 747 748 static int 749 g_io_transient_map_bio(struct bio *bp) 750 { 751 vm_offset_t addr; 752 long size; 753 u_int retried; 754 755 KASSERT(unmapped_buf_allowed, ("unmapped disabled")); 756 757 size = round_page(bp->bio_ma_offset + bp->bio_length); 758 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp)); 759 addr = 0; 760 retried = 0; 761 atomic_add_long(&transient_maps, 1); 762 retry: 763 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) { 764 if (transient_map_retries != 0 && 765 retried >= transient_map_retries) { 766 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s", 767 bp, bp->bio_to->name); 768 atomic_add_int(&transient_map_hard_failures, 1); 769 return (EDEADLK/* XXXKIB */); 770 } else { 771 /* 772 * Naive attempt to quisce the I/O to get more 773 * in-flight requests completed and defragment 774 * the transient_arena. 775 */ 776 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d", 777 bp, bp->bio_to->name, retried); 778 pause("g_d_tra", hz / 10); 779 retried++; 780 atomic_add_int(&transient_map_soft_failures, 1); 781 goto retry; 782 } 783 } 784 atomic_add_int(&inflight_transient_maps, 1); 785 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size)); 786 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset; 787 bp->bio_flags |= BIO_TRANSIENT_MAPPING; 788 bp->bio_flags &= ~BIO_UNMAPPED; 789 return (EJUSTRETURN); 790 } 791 792 void 793 g_io_schedule_down(struct thread *tp __unused) 794 { 795 struct bio *bp; 796 int error; 797 798 for(;;) { 799 g_bioq_lock(&g_bio_run_down); 800 bp = g_bioq_first(&g_bio_run_down); 801 if (bp == NULL) { 802 CTR0(KTR_GEOM, "g_down going to sleep"); 803 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 804 PRIBIO | PDROP, "-", 0); 805 continue; 806 } 807 CTR0(KTR_GEOM, "g_down has work to do"); 808 g_bioq_unlock(&g_bio_run_down); 809 biotrack(bp, __func__); 810 if (pace != 0) { 811 /* 812 * There has been at least one memory allocation failure 813 * since the last I/O completed. Pause 1ms to give the 814 * system a chance to free up memory. Pause time is not 815 * scaled to the number of I/O failures since they tend 816 * to cluster and the number is not predictive of how 817 * long a pause is needed. 818 * 819 * Older versions had a longer pause, which limited the 820 * IOPS to 10, which prolonged memory shortages that could 821 * be alleviated by I/O completing since it eliminated 822 * direct dispatch as well. 823 * 824 * XXX This pacing is really lame. It needs to be solved 825 * by other methods. This is OK only because the worst 826 * case scenario is so rare. In the worst case scenario 827 * all memory is tied up waiting for I/O to complete 828 * which can never happen since we can't allocate bios 829 * for that I/O. 830 */ 831 CTR0(KTR_GEOM, "g_down pacing self"); 832 pause_count++; /* g_down has only one thread */ 833 pause_sbt("g_down", SBT_1MS, 0, 0); 834 pace = 0; 835 } 836 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp, 837 bp->bio_to->name); 838 error = g_io_check(bp); 839 if (error >= 0) { 840 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider " 841 "%s returned %d", bp, bp->bio_to->name, error); 842 g_io_deliver(bp, error); 843 continue; 844 } 845 THREAD_NO_SLEEPING(); 846 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld " 847 "len %ld", bp, bp->bio_to->name, bp->bio_offset, 848 bp->bio_length); 849 bp->bio_to->geom->start(bp); 850 THREAD_SLEEPING_OK(); 851 } 852 } 853 854 void 855 g_io_schedule_up(struct thread *tp __unused) 856 { 857 struct bio *bp; 858 859 for(;;) { 860 g_bioq_lock(&g_bio_run_up); 861 bp = g_bioq_first(&g_bio_run_up); 862 if (bp == NULL) { 863 CTR0(KTR_GEOM, "g_up going to sleep"); 864 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 865 PRIBIO | PDROP, "-", 0); 866 continue; 867 } 868 g_bioq_unlock(&g_bio_run_up); 869 THREAD_NO_SLEEPING(); 870 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off " 871 "%jd len %ld", bp, bp->bio_to->name, 872 bp->bio_offset, bp->bio_length); 873 biodone(bp); 874 THREAD_SLEEPING_OK(); 875 } 876 } 877 878 void * 879 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 880 { 881 struct bio *bp; 882 void *ptr; 883 int errorc; 884 885 KASSERT(length > 0 && length >= cp->provider->sectorsize && 886 length <= maxphys, ("g_read_data(): invalid length %jd", 887 (intmax_t)length)); 888 889 bp = g_alloc_bio(); 890 bp->bio_cmd = BIO_READ; 891 bp->bio_done = NULL; 892 bp->bio_offset = offset; 893 bp->bio_length = length; 894 ptr = g_malloc(length, M_WAITOK); 895 bp->bio_data = ptr; 896 g_io_request(bp, cp); 897 errorc = biowait(bp, "gread"); 898 if (errorc == 0 && bp->bio_completed != length) 899 errorc = EIO; 900 if (error != NULL) 901 *error = errorc; 902 g_destroy_bio(bp); 903 if (errorc) { 904 g_free(ptr); 905 ptr = NULL; 906 } 907 return (ptr); 908 } 909 910 /* 911 * A read function for use by ffs_sbget when used by GEOM-layer routines. 912 */ 913 int 914 g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size) 915 { 916 struct g_consumer *cp; 917 918 KASSERT(*bufp == NULL, 919 ("g_use_g_read_data: non-NULL *bufp %p\n", *bufp)); 920 921 cp = (struct g_consumer *)devfd; 922 /* 923 * Take care not to issue an invalid I/O request. The offset of 924 * the superblock candidate must be multiples of the provider's 925 * sector size, otherwise an FFS can't exist on the provider 926 * anyway. 927 */ 928 if (loc % cp->provider->sectorsize != 0) 929 return (ENOENT); 930 *bufp = g_read_data(cp, loc, size, NULL); 931 if (*bufp == NULL) 932 return (ENOENT); 933 return (0); 934 } 935 936 int 937 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 938 { 939 struct bio *bp; 940 int error; 941 942 KASSERT(length > 0 && length >= cp->provider->sectorsize && 943 length <= maxphys, ("g_write_data(): invalid length %jd", 944 (intmax_t)length)); 945 946 bp = g_alloc_bio(); 947 bp->bio_cmd = BIO_WRITE; 948 bp->bio_done = NULL; 949 bp->bio_offset = offset; 950 bp->bio_length = length; 951 bp->bio_data = ptr; 952 g_io_request(bp, cp); 953 error = biowait(bp, "gwrite"); 954 if (error == 0 && bp->bio_completed != length) 955 error = EIO; 956 g_destroy_bio(bp); 957 return (error); 958 } 959 960 /* 961 * A write function for use by ffs_sbput when used by GEOM-layer routines. 962 */ 963 int 964 g_use_g_write_data(void *devfd, off_t loc, void *buf, int size) 965 { 966 967 return (g_write_data((struct g_consumer *)devfd, loc, buf, size)); 968 } 969 970 int 971 g_delete_data(struct g_consumer *cp, off_t offset, off_t length) 972 { 973 struct bio *bp; 974 int error; 975 976 KASSERT(length > 0 && length >= cp->provider->sectorsize, 977 ("g_delete_data(): invalid length %jd", (intmax_t)length)); 978 979 bp = g_alloc_bio(); 980 bp->bio_cmd = BIO_DELETE; 981 bp->bio_done = NULL; 982 bp->bio_offset = offset; 983 bp->bio_length = length; 984 bp->bio_data = NULL; 985 g_io_request(bp, cp); 986 error = biowait(bp, "gdelete"); 987 if (error == 0 && bp->bio_completed != length) 988 error = EIO; 989 g_destroy_bio(bp); 990 return (error); 991 } 992 993 void 994 g_print_bio(const char *prefix, const struct bio *bp, const char *fmtsuffix, 995 ...) 996 { 997 #ifndef PRINTF_BUFR_SIZE 998 #define PRINTF_BUFR_SIZE 64 999 #endif 1000 char bufr[PRINTF_BUFR_SIZE]; 1001 struct sbuf sb, *sbp __unused; 1002 va_list ap; 1003 1004 sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN); 1005 KASSERT(sbp != NULL, ("sbuf_new misused?")); 1006 1007 sbuf_set_drain(&sb, sbuf_printf_drain, NULL); 1008 1009 sbuf_cat(&sb, prefix); 1010 g_format_bio(&sb, bp); 1011 1012 va_start(ap, fmtsuffix); 1013 sbuf_vprintf(&sb, fmtsuffix, ap); 1014 va_end(ap); 1015 1016 sbuf_nl_terminate(&sb); 1017 1018 sbuf_finish(&sb); 1019 sbuf_delete(&sb); 1020 } 1021 1022 void 1023 g_format_bio(struct sbuf *sb, const struct bio *bp) 1024 { 1025 const char *pname, *cmd = NULL; 1026 1027 if (bp->bio_to != NULL) 1028 pname = bp->bio_to->name; 1029 else if (bp->bio_parent != NULL && bp->bio_parent->bio_to != NULL) 1030 pname = bp->bio_parent->bio_to->name; 1031 else 1032 pname = "[unknown]"; 1033 1034 switch (bp->bio_cmd) { 1035 case BIO_GETATTR: 1036 cmd = "GETATTR"; 1037 sbuf_printf(sb, "%s[%s(attr=%s)]", pname, cmd, 1038 bp->bio_attribute); 1039 return; 1040 case BIO_FLUSH: 1041 cmd = "FLUSH"; 1042 sbuf_printf(sb, "%s[%s]", pname, cmd); 1043 return; 1044 case BIO_ZONE: { 1045 char *subcmd = NULL; 1046 cmd = "ZONE"; 1047 switch (bp->bio_zone.zone_cmd) { 1048 case DISK_ZONE_OPEN: 1049 subcmd = "OPEN"; 1050 break; 1051 case DISK_ZONE_CLOSE: 1052 subcmd = "CLOSE"; 1053 break; 1054 case DISK_ZONE_FINISH: 1055 subcmd = "FINISH"; 1056 break; 1057 case DISK_ZONE_RWP: 1058 subcmd = "RWP"; 1059 break; 1060 case DISK_ZONE_REPORT_ZONES: 1061 subcmd = "REPORT ZONES"; 1062 break; 1063 case DISK_ZONE_GET_PARAMS: 1064 subcmd = "GET PARAMS"; 1065 break; 1066 default: 1067 subcmd = "UNKNOWN"; 1068 break; 1069 } 1070 sbuf_printf(sb, "%s[%s,%s]", pname, cmd, subcmd); 1071 return; 1072 } 1073 case BIO_READ: 1074 cmd = "READ"; 1075 break; 1076 case BIO_WRITE: 1077 cmd = "WRITE"; 1078 break; 1079 case BIO_DELETE: 1080 cmd = "DELETE"; 1081 break; 1082 default: 1083 cmd = "UNKNOWN"; 1084 sbuf_printf(sb, "%s[%s()]", pname, cmd); 1085 return; 1086 } 1087 sbuf_printf(sb, "%s[%s(offset=%jd, length=%jd)]", pname, cmd, 1088 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 1089 } 1090