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sys/geom/geom_io.c
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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/cdefs.h> 43 __FBSDID("$FreeBSD$"); 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/kernel.h> 48 #include <sys/malloc.h> 49 #include <sys/bio.h> 50 #include <sys/ktr.h> 51 #include <sys/proc.h> 52 #include <sys/sbuf.h> 53 #include <sys/stack.h> 54 #include <sys/sysctl.h> 55 #include <sys/vmem.h> 56 #include <machine/stdarg.h> 57 58 #include <sys/errno.h> 59 #include <geom/geom.h> 60 #include <geom/geom_int.h> 61 #include <sys/devicestat.h> 62 63 #include <vm/uma.h> 64 #include <vm/vm.h> 65 #include <vm/vm_param.h> 66 #include <vm/vm_kern.h> 67 #include <vm/vm_page.h> 68 #include <vm/vm_object.h> 69 #include <vm/vm_extern.h> 70 #include <vm/vm_map.h> 71 72 static int g_io_transient_map_bio(struct bio *bp); 73 74 static struct g_bioq g_bio_run_down; 75 static struct g_bioq g_bio_run_up; 76 77 /* 78 * Pace is a hint that we've had some trouble recently allocating 79 * bios, so we should back off trying to send I/O down the stack 80 * a bit to let the problem resolve. When pacing, we also turn 81 * off direct dispatch to also reduce memory pressure from I/Os 82 * there, at the expxense of some added latency while the memory 83 * pressures exist. See g_io_schedule_down() for more details 84 * and limitations. 85 */ 86 static volatile u_int __read_mostly pace; 87 88 static uma_zone_t __read_mostly biozone; 89 90 #include <machine/atomic.h> 91 92 static void 93 g_bioq_lock(struct g_bioq *bq) 94 { 95 96 mtx_lock(&bq->bio_queue_lock); 97 } 98 99 static void 100 g_bioq_unlock(struct g_bioq *bq) 101 { 102 103 mtx_unlock(&bq->bio_queue_lock); 104 } 105 106 #if 0 107 static void 108 g_bioq_destroy(struct g_bioq *bq) 109 { 110 111 mtx_destroy(&bq->bio_queue_lock); 112 } 113 #endif 114 115 static void 116 g_bioq_init(struct g_bioq *bq) 117 { 118 119 TAILQ_INIT(&bq->bio_queue); 120 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 121 } 122 123 static struct bio * 124 g_bioq_first(struct g_bioq *bq) 125 { 126 struct bio *bp; 127 128 bp = TAILQ_FIRST(&bq->bio_queue); 129 if (bp != NULL) { 130 KASSERT((bp->bio_flags & BIO_ONQUEUE), 131 ("Bio not on queue bp=%p target %p", bp, bq)); 132 bp->bio_flags &= ~BIO_ONQUEUE; 133 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 134 bq->bio_queue_length--; 135 } 136 return (bp); 137 } 138 139 struct bio * 140 g_new_bio(void) 141 { 142 struct bio *bp; 143 144 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 145 #ifdef KTR 146 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 147 struct stack st; 148 149 CTR1(KTR_GEOM, "g_new_bio(): %p", bp); 150 stack_save(&st); 151 CTRSTACK(KTR_GEOM, &st, 3); 152 } 153 #endif 154 return (bp); 155 } 156 157 struct bio * 158 g_alloc_bio(void) 159 { 160 struct bio *bp; 161 162 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); 163 #ifdef KTR 164 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 165 struct stack st; 166 167 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp); 168 stack_save(&st); 169 CTRSTACK(KTR_GEOM, &st, 3); 170 } 171 #endif 172 return (bp); 173 } 174 175 void 176 g_destroy_bio(struct bio *bp) 177 { 178 #ifdef KTR 179 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 180 struct stack st; 181 182 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp); 183 stack_save(&st); 184 CTRSTACK(KTR_GEOM, &st, 3); 185 } 186 #endif 187 uma_zfree(biozone, bp); 188 } 189 190 struct bio * 191 g_clone_bio(struct bio *bp) 192 { 193 struct bio *bp2; 194 195 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 196 if (bp2 != NULL) { 197 bp2->bio_parent = bp; 198 bp2->bio_cmd = bp->bio_cmd; 199 /* 200 * BIO_ORDERED flag may be used by disk drivers to enforce 201 * ordering restrictions, so this flag needs to be cloned. 202 * BIO_UNMAPPED, BIO_VLIST, and BIO_SWAP should be inherited, 203 * to properly indicate which way the buffer is passed. 204 * Other bio flags are not suitable for cloning. 205 */ 206 bp2->bio_flags = bp->bio_flags & 207 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST | BIO_SWAP); 208 bp2->bio_length = bp->bio_length; 209 bp2->bio_offset = bp->bio_offset; 210 bp2->bio_data = bp->bio_data; 211 bp2->bio_ma = bp->bio_ma; 212 bp2->bio_ma_n = bp->bio_ma_n; 213 bp2->bio_ma_offset = bp->bio_ma_offset; 214 bp2->bio_attribute = bp->bio_attribute; 215 if (bp->bio_cmd == BIO_ZONE) 216 bcopy(&bp->bio_zone, &bp2->bio_zone, 217 sizeof(bp->bio_zone)); 218 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 219 bp2->bio_track_bp = bp->bio_track_bp; 220 #endif 221 bp->bio_children++; 222 } 223 #ifdef KTR 224 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 225 struct stack st; 226 227 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2); 228 stack_save(&st); 229 CTRSTACK(KTR_GEOM, &st, 3); 230 } 231 #endif 232 return(bp2); 233 } 234 235 struct bio * 236 g_duplicate_bio(struct bio *bp) 237 { 238 struct bio *bp2; 239 240 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO); 241 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST | BIO_SWAP); 242 bp2->bio_parent = bp; 243 bp2->bio_cmd = bp->bio_cmd; 244 bp2->bio_length = bp->bio_length; 245 bp2->bio_offset = bp->bio_offset; 246 bp2->bio_data = bp->bio_data; 247 bp2->bio_ma = bp->bio_ma; 248 bp2->bio_ma_n = bp->bio_ma_n; 249 bp2->bio_ma_offset = bp->bio_ma_offset; 250 bp2->bio_attribute = bp->bio_attribute; 251 bp->bio_children++; 252 #ifdef KTR 253 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 254 struct stack st; 255 256 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2); 257 stack_save(&st); 258 CTRSTACK(KTR_GEOM, &st, 3); 259 } 260 #endif 261 return(bp2); 262 } 263 264 void 265 g_reset_bio(struct bio *bp) 266 { 267 268 bzero(bp, sizeof(*bp)); 269 } 270 271 void 272 g_io_init(void) 273 { 274 275 g_bioq_init(&g_bio_run_down); 276 g_bioq_init(&g_bio_run_up); 277 biozone = uma_zcreate("g_bio", sizeof (struct bio), 278 NULL, NULL, 279 NULL, NULL, 280 0, 0); 281 } 282 283 int 284 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 285 { 286 struct bio *bp; 287 int error; 288 289 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 290 bp = g_alloc_bio(); 291 bp->bio_cmd = BIO_GETATTR; 292 bp->bio_done = NULL; 293 bp->bio_attribute = attr; 294 bp->bio_length = *len; 295 bp->bio_data = ptr; 296 g_io_request(bp, cp); 297 error = biowait(bp, "ggetattr"); 298 *len = bp->bio_completed; 299 g_destroy_bio(bp); 300 return (error); 301 } 302 303 int 304 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp) 305 { 306 struct bio *bp; 307 int error; 308 309 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd); 310 bp = g_alloc_bio(); 311 bp->bio_cmd = BIO_ZONE; 312 bp->bio_done = NULL; 313 /* 314 * XXX KDM need to handle report zone data. 315 */ 316 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args)); 317 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) 318 bp->bio_length = 319 zone_args->zone_params.report.entries_allocated * 320 sizeof(struct disk_zone_rep_entry); 321 else 322 bp->bio_length = 0; 323 324 g_io_request(bp, cp); 325 error = biowait(bp, "gzone"); 326 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args)); 327 g_destroy_bio(bp); 328 return (error); 329 } 330 331 /* 332 * Send a BIO_SPEEDUP down the stack. This is used to tell the lower layers that 333 * the upper layers have detected a resource shortage. The lower layers are 334 * advised to stop delaying I/O that they might be holding for performance 335 * reasons and to schedule it (non-trims) or complete it successfully (trims) as 336 * quickly as it can. bio_length is the amount of the shortage. This call 337 * should be non-blocking. bio_resid is used to communicate back if the lower 338 * layers couldn't find bio_length worth of I/O to schedule or discard. A length 339 * of 0 means to do as much as you can (schedule the h/w queues full, discard 340 * all trims). flags are a hint from the upper layers to the lower layers what 341 * operation should be done. 342 */ 343 int 344 g_io_speedup(off_t shortage, u_int flags, size_t *resid, struct g_consumer *cp) 345 { 346 struct bio *bp; 347 int error; 348 349 KASSERT((flags & (BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE)) != 0, 350 ("Invalid flags passed to g_io_speedup: %#x", flags)); 351 g_trace(G_T_BIO, "bio_speedup(%s, %jd, %#x)", cp->provider->name, 352 (intmax_t)shortage, flags); 353 bp = g_new_bio(); 354 if (bp == NULL) 355 return (ENOMEM); 356 bp->bio_cmd = BIO_SPEEDUP; 357 bp->bio_length = shortage; 358 bp->bio_done = NULL; 359 bp->bio_flags |= flags; 360 g_io_request(bp, cp); 361 error = biowait(bp, "gflush"); 362 *resid = bp->bio_resid; 363 g_destroy_bio(bp); 364 return (error); 365 } 366 367 int 368 g_io_flush(struct g_consumer *cp) 369 { 370 struct bio *bp; 371 int error; 372 373 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name); 374 bp = g_alloc_bio(); 375 bp->bio_cmd = BIO_FLUSH; 376 bp->bio_flags |= BIO_ORDERED; 377 bp->bio_done = NULL; 378 bp->bio_attribute = NULL; 379 bp->bio_offset = cp->provider->mediasize; 380 bp->bio_length = 0; 381 bp->bio_data = NULL; 382 g_io_request(bp, cp); 383 error = biowait(bp, "gflush"); 384 g_destroy_bio(bp); 385 return (error); 386 } 387 388 static int 389 g_io_check(struct bio *bp) 390 { 391 struct g_consumer *cp; 392 struct g_provider *pp; 393 off_t excess; 394 int error; 395 396 biotrack(bp, __func__); 397 398 cp = bp->bio_from; 399 pp = bp->bio_to; 400 401 /* Fail if access counters dont allow the operation */ 402 switch(bp->bio_cmd) { 403 case BIO_READ: 404 case BIO_GETATTR: 405 if (cp->acr == 0) 406 return (EPERM); 407 break; 408 case BIO_WRITE: 409 case BIO_DELETE: 410 case BIO_SPEEDUP: 411 case BIO_FLUSH: 412 if (cp->acw == 0) 413 return (EPERM); 414 break; 415 case BIO_ZONE: 416 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) || 417 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) { 418 if (cp->acr == 0) 419 return (EPERM); 420 } else if (cp->acw == 0) 421 return (EPERM); 422 break; 423 default: 424 return (EPERM); 425 } 426 /* if provider is marked for error, don't disturb. */ 427 if (pp->error) 428 return (pp->error); 429 if (cp->flags & G_CF_ORPHAN) 430 return (ENXIO); 431 432 switch(bp->bio_cmd) { 433 case BIO_READ: 434 case BIO_WRITE: 435 case BIO_DELETE: 436 /* Zero sectorsize or mediasize is probably a lack of media. */ 437 if (pp->sectorsize == 0 || pp->mediasize == 0) 438 return (ENXIO); 439 /* Reject I/O not on sector boundary */ 440 if (bp->bio_offset % pp->sectorsize) 441 return (EINVAL); 442 /* Reject I/O not integral sector long */ 443 if (bp->bio_length % pp->sectorsize) 444 return (EINVAL); 445 /* Reject requests before or past the end of media. */ 446 if (bp->bio_offset < 0) 447 return (EIO); 448 if (bp->bio_offset > pp->mediasize) 449 return (EIO); 450 451 /* Truncate requests to the end of providers media. */ 452 excess = bp->bio_offset + bp->bio_length; 453 if (excess > bp->bio_to->mediasize) { 454 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 || 455 round_page(bp->bio_ma_offset + 456 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n, 457 ("excess bio %p too short", bp)); 458 excess -= bp->bio_to->mediasize; 459 bp->bio_length -= excess; 460 if ((bp->bio_flags & BIO_UNMAPPED) != 0) { 461 bp->bio_ma_n = round_page(bp->bio_ma_offset + 462 bp->bio_length) / PAGE_SIZE; 463 } 464 if (excess > 0) 465 CTR3(KTR_GEOM, "g_down truncated bio " 466 "%p provider %s by %d", bp, 467 bp->bio_to->name, excess); 468 } 469 470 /* Deliver zero length transfers right here. */ 471 if (bp->bio_length == 0) { 472 CTR2(KTR_GEOM, "g_down terminated 0-length " 473 "bp %p provider %s", bp, bp->bio_to->name); 474 return (0); 475 } 476 477 if ((bp->bio_flags & BIO_UNMAPPED) != 0 && 478 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 && 479 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) { 480 if ((error = g_io_transient_map_bio(bp)) >= 0) 481 return (error); 482 } 483 break; 484 default: 485 break; 486 } 487 return (EJUSTRETURN); 488 } 489 490 void 491 g_io_request(struct bio *bp, struct g_consumer *cp) 492 { 493 struct g_provider *pp; 494 int direct, error, first; 495 uint8_t cmd; 496 497 biotrack(bp, __func__); 498 499 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 500 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 501 pp = cp->provider; 502 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 503 #ifdef DIAGNOSTIC 504 KASSERT(bp->bio_driver1 == NULL, 505 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name)); 506 KASSERT(bp->bio_driver2 == NULL, 507 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name)); 508 KASSERT(bp->bio_pflags == 0, 509 ("bio_pflags used by the consumer (geom %s)", cp->geom->name)); 510 /* 511 * Remember consumer's private fields, so we can detect if they were 512 * modified by the provider. 513 */ 514 bp->_bio_caller1 = bp->bio_caller1; 515 bp->_bio_caller2 = bp->bio_caller2; 516 bp->_bio_cflags = bp->bio_cflags; 517 #endif 518 519 cmd = bp->bio_cmd; 520 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) { 521 KASSERT(bp->bio_data != NULL, 522 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd)); 523 } 524 if (cmd == BIO_DELETE || cmd == BIO_FLUSH || cmd == BIO_SPEEDUP) { 525 KASSERT(bp->bio_data == NULL, 526 ("non-NULL bp->data in g_io_request(cmd=%hu)", 527 bp->bio_cmd)); 528 } 529 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) { 530 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, 531 ("wrong offset %jd for sectorsize %u", 532 bp->bio_offset, cp->provider->sectorsize)); 533 KASSERT(bp->bio_length % cp->provider->sectorsize == 0, 534 ("wrong length %jd for sectorsize %u", 535 bp->bio_length, cp->provider->sectorsize)); 536 } 537 538 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 539 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 540 541 bp->bio_from = cp; 542 bp->bio_to = pp; 543 bp->bio_error = 0; 544 bp->bio_completed = 0; 545 546 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 547 ("Bio already on queue bp=%p", bp)); 548 549 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 550 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 551 binuptime(&bp->bio_t0); 552 else 553 getbinuptime(&bp->bio_t0); 554 if (g_collectstats & G_STATS_CONSUMERS) 555 devstat_start_transaction_bio_t0(cp->stat, bp); 556 if (g_collectstats & G_STATS_PROVIDERS) 557 devstat_start_transaction_bio_t0(pp->stat, bp); 558 #ifdef INVARIANTS 559 atomic_add_int(&cp->nstart, 1); 560 #endif 561 562 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 && 563 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 && 564 curthread != g_down_td && 565 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 || 566 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) && 567 pace == 0; 568 if (direct) { 569 /* Block direct execution if less then half of stack left. */ 570 size_t st, su; 571 GET_STACK_USAGE(st, su); 572 if (su * 2 > st) 573 direct = 0; 574 } 575 576 if (direct) { 577 error = g_io_check(bp); 578 if (error >= 0) { 579 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p " 580 "provider %s returned %d", bp, bp->bio_to->name, 581 error); 582 g_io_deliver(bp, error); 583 return; 584 } 585 bp->bio_to->geom->start(bp); 586 } else { 587 g_bioq_lock(&g_bio_run_down); 588 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue); 589 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue); 590 bp->bio_flags |= BIO_ONQUEUE; 591 g_bio_run_down.bio_queue_length++; 592 g_bioq_unlock(&g_bio_run_down); 593 /* Pass it on down. */ 594 if (first) 595 wakeup(&g_wait_down); 596 } 597 } 598 599 void 600 g_io_deliver(struct bio *bp, int error) 601 { 602 struct bintime now; 603 struct g_consumer *cp; 604 struct g_provider *pp; 605 struct mtx *mtxp; 606 int direct, first; 607 608 biotrack(bp, __func__); 609 610 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 611 pp = bp->bio_to; 612 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 613 cp = bp->bio_from; 614 if (cp == NULL) { 615 bp->bio_error = error; 616 bp->bio_done(bp); 617 return; 618 } 619 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 620 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 621 #ifdef DIAGNOSTIC 622 /* 623 * Some classes - GJournal in particular - can modify bio's 624 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO 625 * flag means it's an expected behaviour for that particular geom. 626 */ 627 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) { 628 KASSERT(bp->bio_caller1 == bp->_bio_caller1, 629 ("bio_caller1 used by the provider %s", pp->name)); 630 KASSERT(bp->bio_caller2 == bp->_bio_caller2, 631 ("bio_caller2 used by the provider %s", pp->name)); 632 KASSERT(bp->bio_cflags == bp->_bio_cflags, 633 ("bio_cflags used by the provider %s", pp->name)); 634 } 635 #endif 636 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 637 KASSERT(bp->bio_completed <= bp->bio_length, 638 ("bio_completed can't be greater than bio_length")); 639 640 g_trace(G_T_BIO, 641 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 642 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 643 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 644 645 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 646 ("Bio already on queue bp=%p", bp)); 647 648 /* 649 * XXX: next two doesn't belong here 650 */ 651 bp->bio_bcount = bp->bio_length; 652 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 653 654 direct = (pp->flags & G_PF_DIRECT_SEND) && 655 (cp->flags & G_CF_DIRECT_RECEIVE) && 656 curthread != g_up_td; 657 if (direct) { 658 /* Block direct execution if less then half of stack left. */ 659 size_t st, su; 660 GET_STACK_USAGE(st, su); 661 if (su * 2 > st) 662 direct = 0; 663 } 664 665 /* 666 * The statistics collection is lockless, as such, but we 667 * can not update one instance of the statistics from more 668 * than one thread at a time, so grab the lock first. 669 */ 670 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 671 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 672 binuptime(&now); 673 mtxp = mtx_pool_find(mtxpool_sleep, pp); 674 mtx_lock(mtxp); 675 if (g_collectstats & G_STATS_PROVIDERS) 676 devstat_end_transaction_bio_bt(pp->stat, bp, &now); 677 if (g_collectstats & G_STATS_CONSUMERS) 678 devstat_end_transaction_bio_bt(cp->stat, bp, &now); 679 #ifdef INVARIANTS 680 cp->nend++; 681 #endif 682 mtx_unlock(mtxp); 683 684 if (error != ENOMEM) { 685 bp->bio_error = error; 686 if (direct) { 687 biodone(bp); 688 } else { 689 g_bioq_lock(&g_bio_run_up); 690 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue); 691 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue); 692 bp->bio_flags |= BIO_ONQUEUE; 693 g_bio_run_up.bio_queue_length++; 694 g_bioq_unlock(&g_bio_run_up); 695 if (first) 696 wakeup(&g_wait_up); 697 } 698 return; 699 } 700 701 if (bootverbose) 702 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 703 bp->bio_children = 0; 704 bp->bio_inbed = 0; 705 bp->bio_driver1 = NULL; 706 bp->bio_driver2 = NULL; 707 bp->bio_pflags = 0; 708 g_io_request(bp, cp); 709 pace = 1; 710 return; 711 } 712 713 SYSCTL_DECL(_kern_geom); 714 715 static long transient_maps; 716 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD, 717 &transient_maps, 0, 718 "Total count of the transient mapping requests"); 719 u_int transient_map_retries = 10; 720 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW, 721 &transient_map_retries, 0, 722 "Max count of retries used before giving up on creating transient map"); 723 int transient_map_hard_failures; 724 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD, 725 &transient_map_hard_failures, 0, 726 "Failures to establish the transient mapping due to retry attempts " 727 "exhausted"); 728 int transient_map_soft_failures; 729 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD, 730 &transient_map_soft_failures, 0, 731 "Count of retried failures to establish the transient mapping"); 732 int inflight_transient_maps; 733 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD, 734 &inflight_transient_maps, 0, 735 "Current count of the active transient maps"); 736 737 static int 738 g_io_transient_map_bio(struct bio *bp) 739 { 740 vm_offset_t addr; 741 long size; 742 u_int retried; 743 744 KASSERT(unmapped_buf_allowed, ("unmapped disabled")); 745 746 size = round_page(bp->bio_ma_offset + bp->bio_length); 747 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp)); 748 addr = 0; 749 retried = 0; 750 atomic_add_long(&transient_maps, 1); 751 retry: 752 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) { 753 if (transient_map_retries != 0 && 754 retried >= transient_map_retries) { 755 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s", 756 bp, bp->bio_to->name); 757 atomic_add_int(&transient_map_hard_failures, 1); 758 return (EDEADLK/* XXXKIB */); 759 } else { 760 /* 761 * Naive attempt to quisce the I/O to get more 762 * in-flight requests completed and defragment 763 * the transient_arena. 764 */ 765 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d", 766 bp, bp->bio_to->name, retried); 767 pause("g_d_tra", hz / 10); 768 retried++; 769 atomic_add_int(&transient_map_soft_failures, 1); 770 goto retry; 771 } 772 } 773 atomic_add_int(&inflight_transient_maps, 1); 774 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size)); 775 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset; 776 bp->bio_flags |= BIO_TRANSIENT_MAPPING; 777 bp->bio_flags &= ~BIO_UNMAPPED; 778 return (EJUSTRETURN); 779 } 780 781 void 782 g_io_schedule_down(struct thread *tp __unused) 783 { 784 struct bio *bp; 785 int error; 786 787 for(;;) { 788 g_bioq_lock(&g_bio_run_down); 789 bp = g_bioq_first(&g_bio_run_down); 790 if (bp == NULL) { 791 CTR0(KTR_GEOM, "g_down going to sleep"); 792 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 793 PRIBIO | PDROP, "-", 0); 794 continue; 795 } 796 CTR0(KTR_GEOM, "g_down has work to do"); 797 g_bioq_unlock(&g_bio_run_down); 798 biotrack(bp, __func__); 799 if (pace != 0) { 800 /* 801 * There has been at least one memory allocation 802 * failure since the last I/O completed. Pause 1ms to 803 * give the system a chance to free up memory. We only 804 * do this once because a large number of allocations 805 * can fail in the direct dispatch case and there's no 806 * relationship between the number of these failures and 807 * the length of the outage. If there's still an outage, 808 * we'll pause again and again until it's 809 * resolved. Older versions paused longer and once per 810 * allocation failure. This was OK for a single threaded 811 * g_down, but with direct dispatch would lead to max of 812 * 10 IOPs for minutes at a time when transient memory 813 * issues prevented allocation for a batch of requests 814 * from the upper layers. 815 * 816 * XXX This pacing is really lame. It needs to be solved 817 * by other methods. This is OK only because the worst 818 * case scenario is so rare. In the worst case scenario 819 * all memory is tied up waiting for I/O to complete 820 * which can never happen since we can't allocate bios 821 * for that I/O. 822 */ 823 CTR0(KTR_GEOM, "g_down pacing self"); 824 pause("g_down", min(hz/1000, 1)); 825 pace = 0; 826 } 827 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp, 828 bp->bio_to->name); 829 error = g_io_check(bp); 830 if (error >= 0) { 831 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider " 832 "%s returned %d", bp, bp->bio_to->name, error); 833 g_io_deliver(bp, error); 834 continue; 835 } 836 THREAD_NO_SLEEPING(); 837 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld " 838 "len %ld", bp, bp->bio_to->name, bp->bio_offset, 839 bp->bio_length); 840 bp->bio_to->geom->start(bp); 841 THREAD_SLEEPING_OK(); 842 } 843 } 844 845 void 846 g_io_schedule_up(struct thread *tp __unused) 847 { 848 struct bio *bp; 849 850 for(;;) { 851 g_bioq_lock(&g_bio_run_up); 852 bp = g_bioq_first(&g_bio_run_up); 853 if (bp == NULL) { 854 CTR0(KTR_GEOM, "g_up going to sleep"); 855 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 856 PRIBIO | PDROP, "-", 0); 857 continue; 858 } 859 g_bioq_unlock(&g_bio_run_up); 860 THREAD_NO_SLEEPING(); 861 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off " 862 "%jd len %ld", bp, bp->bio_to->name, 863 bp->bio_offset, bp->bio_length); 864 biodone(bp); 865 THREAD_SLEEPING_OK(); 866 } 867 } 868 869 void * 870 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 871 { 872 struct bio *bp; 873 void *ptr; 874 int errorc; 875 876 KASSERT(length > 0 && length >= cp->provider->sectorsize && 877 length <= maxphys, ("g_read_data(): invalid length %jd", 878 (intmax_t)length)); 879 880 bp = g_alloc_bio(); 881 bp->bio_cmd = BIO_READ; 882 bp->bio_done = NULL; 883 bp->bio_offset = offset; 884 bp->bio_length = length; 885 ptr = g_malloc(length, M_WAITOK); 886 bp->bio_data = ptr; 887 g_io_request(bp, cp); 888 errorc = biowait(bp, "gread"); 889 if (errorc == 0 && bp->bio_completed != length) 890 errorc = EIO; 891 if (error != NULL) 892 *error = errorc; 893 g_destroy_bio(bp); 894 if (errorc) { 895 g_free(ptr); 896 ptr = NULL; 897 } 898 return (ptr); 899 } 900 901 /* 902 * A read function for use by ffs_sbget when used by GEOM-layer routines. 903 */ 904 int 905 g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size) 906 { 907 struct g_consumer *cp; 908 909 KASSERT(*bufp == NULL, 910 ("g_use_g_read_data: non-NULL *bufp %p\n", *bufp)); 911 912 cp = (struct g_consumer *)devfd; 913 /* 914 * Take care not to issue an invalid I/O request. The offset of 915 * the superblock candidate must be multiples of the provider's 916 * sector size, otherwise an FFS can't exist on the provider 917 * anyway. 918 */ 919 if (loc % cp->provider->sectorsize != 0) 920 return (ENOENT); 921 *bufp = g_read_data(cp, loc, size, NULL); 922 if (*bufp == NULL) 923 return (ENOENT); 924 return (0); 925 } 926 927 int 928 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 929 { 930 struct bio *bp; 931 int error; 932 933 KASSERT(length > 0 && length >= cp->provider->sectorsize && 934 length <= maxphys, ("g_write_data(): invalid length %jd", 935 (intmax_t)length)); 936 937 bp = g_alloc_bio(); 938 bp->bio_cmd = BIO_WRITE; 939 bp->bio_done = NULL; 940 bp->bio_offset = offset; 941 bp->bio_length = length; 942 bp->bio_data = ptr; 943 g_io_request(bp, cp); 944 error = biowait(bp, "gwrite"); 945 if (error == 0 && bp->bio_completed != length) 946 error = EIO; 947 g_destroy_bio(bp); 948 return (error); 949 } 950 951 /* 952 * A write function for use by ffs_sbput when used by GEOM-layer routines. 953 */ 954 int 955 g_use_g_write_data(void *devfd, off_t loc, void *buf, int size) 956 { 957 958 return (g_write_data((struct g_consumer *)devfd, loc, buf, size)); 959 } 960 961 int 962 g_delete_data(struct g_consumer *cp, off_t offset, off_t length) 963 { 964 struct bio *bp; 965 int error; 966 967 KASSERT(length > 0 && length >= cp->provider->sectorsize, 968 ("g_delete_data(): invalid length %jd", (intmax_t)length)); 969 970 bp = g_alloc_bio(); 971 bp->bio_cmd = BIO_DELETE; 972 bp->bio_done = NULL; 973 bp->bio_offset = offset; 974 bp->bio_length = length; 975 bp->bio_data = NULL; 976 g_io_request(bp, cp); 977 error = biowait(bp, "gdelete"); 978 if (error == 0 && bp->bio_completed != length) 979 error = EIO; 980 g_destroy_bio(bp); 981 return (error); 982 } 983 984 void 985 g_print_bio(const char *prefix, const struct bio *bp, const char *fmtsuffix, 986 ...) 987 { 988 #ifndef PRINTF_BUFR_SIZE 989 #define PRINTF_BUFR_SIZE 64 990 #endif 991 char bufr[PRINTF_BUFR_SIZE]; 992 struct sbuf sb, *sbp __unused; 993 va_list ap; 994 995 sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN); 996 KASSERT(sbp != NULL, ("sbuf_new misused?")); 997 998 sbuf_set_drain(&sb, sbuf_printf_drain, NULL); 999 1000 sbuf_cat(&sb, prefix); 1001 g_format_bio(&sb, bp); 1002 1003 va_start(ap, fmtsuffix); 1004 sbuf_vprintf(&sb, fmtsuffix, ap); 1005 va_end(ap); 1006 1007 sbuf_nl_terminate(&sb); 1008 1009 sbuf_finish(&sb); 1010 sbuf_delete(&sb); 1011 } 1012 1013 void 1014 g_format_bio(struct sbuf *sb, const struct bio *bp) 1015 { 1016 const char *pname, *cmd = NULL; 1017 1018 if (bp->bio_to != NULL) 1019 pname = bp->bio_to->name; 1020 else if (bp->bio_parent != NULL && bp->bio_parent->bio_to != NULL) 1021 pname = bp->bio_parent->bio_to->name; 1022 else 1023 pname = "[unknown]"; 1024 1025 switch (bp->bio_cmd) { 1026 case BIO_GETATTR: 1027 cmd = "GETATTR"; 1028 sbuf_printf(sb, "%s[%s(attr=%s)]", pname, cmd, 1029 bp->bio_attribute); 1030 return; 1031 case BIO_FLUSH: 1032 cmd = "FLUSH"; 1033 sbuf_printf(sb, "%s[%s]", pname, cmd); 1034 return; 1035 case BIO_ZONE: { 1036 char *subcmd = NULL; 1037 cmd = "ZONE"; 1038 switch (bp->bio_zone.zone_cmd) { 1039 case DISK_ZONE_OPEN: 1040 subcmd = "OPEN"; 1041 break; 1042 case DISK_ZONE_CLOSE: 1043 subcmd = "CLOSE"; 1044 break; 1045 case DISK_ZONE_FINISH: 1046 subcmd = "FINISH"; 1047 break; 1048 case DISK_ZONE_RWP: 1049 subcmd = "RWP"; 1050 break; 1051 case DISK_ZONE_REPORT_ZONES: 1052 subcmd = "REPORT ZONES"; 1053 break; 1054 case DISK_ZONE_GET_PARAMS: 1055 subcmd = "GET PARAMS"; 1056 break; 1057 default: 1058 subcmd = "UNKNOWN"; 1059 break; 1060 } 1061 sbuf_printf(sb, "%s[%s,%s]", pname, cmd, subcmd); 1062 return; 1063 } 1064 case BIO_READ: 1065 cmd = "READ"; 1066 break; 1067 case BIO_WRITE: 1068 cmd = "WRITE"; 1069 break; 1070 case BIO_DELETE: 1071 cmd = "DELETE"; 1072 break; 1073 default: 1074 cmd = "UNKNOWN"; 1075 sbuf_printf(sb, "%s[%s()]", pname, cmd); 1076 return; 1077 } 1078 sbuf_printf(sb, "%s[%s(offset=%jd, length=%jd)]", pname, cmd, 1079 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 1080 }
Cache object: dc2897885f90dfc2ebc033beacae0fa2
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