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/stack.h> 53 #include <sys/sysctl.h> 54 #include <sys/vmem.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 static int g_io_transient_map_bio(struct bio *bp); 71 72 static struct g_bioq g_bio_run_down; 73 static struct g_bioq g_bio_run_up; 74 75 /* 76 * Pace is a hint that we've had some trouble recently allocating 77 * bios, so we should back off trying to send I/O down the stack 78 * a bit to let the problem resolve. When pacing, we also turn 79 * off direct dispatch to also reduce memory pressure from I/Os 80 * there, at the expxense of some added latency while the memory 81 * pressures exist. See g_io_schedule_down() for more details 82 * and limitations. 83 */ 84 static volatile u_int pace; 85 86 static uma_zone_t biozone; 87 88 /* 89 * The head of the list of classifiers used in g_io_request. 90 * Use g_register_classifier() and g_unregister_classifier() 91 * to add/remove entries to the list. 92 * Classifiers are invoked in registration order. 93 */ 94 static TAILQ_HEAD(g_classifier_tailq, g_classifier_hook) 95 g_classifier_tailq = TAILQ_HEAD_INITIALIZER(g_classifier_tailq); 96 97 #include <machine/atomic.h> 98 99 static void 100 g_bioq_lock(struct g_bioq *bq) 101 { 102 103 mtx_lock(&bq->bio_queue_lock); 104 } 105 106 static void 107 g_bioq_unlock(struct g_bioq *bq) 108 { 109 110 mtx_unlock(&bq->bio_queue_lock); 111 } 112 113 #if 0 114 static void 115 g_bioq_destroy(struct g_bioq *bq) 116 { 117 118 mtx_destroy(&bq->bio_queue_lock); 119 } 120 #endif 121 122 static void 123 g_bioq_init(struct g_bioq *bq) 124 { 125 126 TAILQ_INIT(&bq->bio_queue); 127 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 128 } 129 130 static struct bio * 131 g_bioq_first(struct g_bioq *bq) 132 { 133 struct bio *bp; 134 135 bp = TAILQ_FIRST(&bq->bio_queue); 136 if (bp != NULL) { 137 KASSERT((bp->bio_flags & BIO_ONQUEUE), 138 ("Bio not on queue bp=%p target %p", bp, bq)); 139 bp->bio_flags &= ~BIO_ONQUEUE; 140 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 141 bq->bio_queue_length--; 142 } 143 return (bp); 144 } 145 146 struct bio * 147 g_new_bio(void) 148 { 149 struct bio *bp; 150 151 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 152 #ifdef KTR 153 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 154 struct stack st; 155 156 CTR1(KTR_GEOM, "g_new_bio(): %p", bp); 157 stack_save(&st); 158 CTRSTACK(KTR_GEOM, &st, 3, 0); 159 } 160 #endif 161 return (bp); 162 } 163 164 struct bio * 165 g_alloc_bio(void) 166 { 167 struct bio *bp; 168 169 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); 170 #ifdef KTR 171 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 172 struct stack st; 173 174 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp); 175 stack_save(&st); 176 CTRSTACK(KTR_GEOM, &st, 3, 0); 177 } 178 #endif 179 return (bp); 180 } 181 182 void 183 g_destroy_bio(struct bio *bp) 184 { 185 #ifdef KTR 186 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 187 struct stack st; 188 189 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp); 190 stack_save(&st); 191 CTRSTACK(KTR_GEOM, &st, 3, 0); 192 } 193 #endif 194 uma_zfree(biozone, bp); 195 } 196 197 struct bio * 198 g_clone_bio(struct bio *bp) 199 { 200 struct bio *bp2; 201 202 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 203 if (bp2 != NULL) { 204 bp2->bio_parent = bp; 205 bp2->bio_cmd = bp->bio_cmd; 206 /* 207 * BIO_ORDERED flag may be used by disk drivers to enforce 208 * ordering restrictions, so this flag needs to be cloned. 209 * BIO_UNMAPPED and BIO_VLIST should be inherited, to properly 210 * indicate which way the buffer is passed. 211 * Other bio flags are not suitable for cloning. 212 */ 213 bp2->bio_flags = bp->bio_flags & 214 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST); 215 bp2->bio_length = bp->bio_length; 216 bp2->bio_offset = bp->bio_offset; 217 bp2->bio_data = bp->bio_data; 218 bp2->bio_ma = bp->bio_ma; 219 bp2->bio_ma_n = bp->bio_ma_n; 220 bp2->bio_ma_offset = bp->bio_ma_offset; 221 bp2->bio_attribute = bp->bio_attribute; 222 if (bp->bio_cmd == BIO_ZONE) 223 bcopy(&bp->bio_zone, &bp2->bio_zone, 224 sizeof(bp->bio_zone)); 225 /* Inherit classification info from the parent */ 226 bp2->bio_classifier1 = bp->bio_classifier1; 227 bp2->bio_classifier2 = bp->bio_classifier2; 228 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 229 bp2->bio_track_bp = bp->bio_track_bp; 230 #endif 231 bp->bio_children++; 232 } 233 #ifdef KTR 234 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 235 struct stack st; 236 237 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2); 238 stack_save(&st); 239 CTRSTACK(KTR_GEOM, &st, 3, 0); 240 } 241 #endif 242 return(bp2); 243 } 244 245 struct bio * 246 g_duplicate_bio(struct bio *bp) 247 { 248 struct bio *bp2; 249 250 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO); 251 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST); 252 bp2->bio_parent = bp; 253 bp2->bio_cmd = bp->bio_cmd; 254 bp2->bio_length = bp->bio_length; 255 bp2->bio_offset = bp->bio_offset; 256 bp2->bio_data = bp->bio_data; 257 bp2->bio_ma = bp->bio_ma; 258 bp2->bio_ma_n = bp->bio_ma_n; 259 bp2->bio_ma_offset = bp->bio_ma_offset; 260 bp2->bio_attribute = bp->bio_attribute; 261 bp->bio_children++; 262 #ifdef KTR 263 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 264 struct stack st; 265 266 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2); 267 stack_save(&st); 268 CTRSTACK(KTR_GEOM, &st, 3, 0); 269 } 270 #endif 271 return(bp2); 272 } 273 274 void 275 g_reset_bio(struct bio *bp) 276 { 277 278 bzero(bp, sizeof(*bp)); 279 } 280 281 void 282 g_io_init() 283 { 284 285 g_bioq_init(&g_bio_run_down); 286 g_bioq_init(&g_bio_run_up); 287 biozone = uma_zcreate("g_bio", sizeof (struct bio), 288 NULL, NULL, 289 NULL, NULL, 290 0, 0); 291 } 292 293 int 294 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 295 { 296 struct bio *bp; 297 int error; 298 299 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 300 bp = g_alloc_bio(); 301 bp->bio_cmd = BIO_GETATTR; 302 bp->bio_done = NULL; 303 bp->bio_attribute = attr; 304 bp->bio_length = *len; 305 bp->bio_data = ptr; 306 g_io_request(bp, cp); 307 error = biowait(bp, "ggetattr"); 308 *len = bp->bio_completed; 309 g_destroy_bio(bp); 310 return (error); 311 } 312 313 int 314 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp) 315 { 316 struct bio *bp; 317 int error; 318 319 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd); 320 bp = g_alloc_bio(); 321 bp->bio_cmd = BIO_ZONE; 322 bp->bio_done = NULL; 323 /* 324 * XXX KDM need to handle report zone data. 325 */ 326 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args)); 327 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) 328 bp->bio_length = 329 zone_args->zone_params.report.entries_allocated * 330 sizeof(struct disk_zone_rep_entry); 331 else 332 bp->bio_length = 0; 333 334 g_io_request(bp, cp); 335 error = biowait(bp, "gzone"); 336 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args)); 337 g_destroy_bio(bp); 338 return (error); 339 } 340 341 int 342 g_io_flush(struct g_consumer *cp) 343 { 344 struct bio *bp; 345 int error; 346 347 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name); 348 bp = g_alloc_bio(); 349 bp->bio_cmd = BIO_FLUSH; 350 bp->bio_flags |= BIO_ORDERED; 351 bp->bio_done = NULL; 352 bp->bio_attribute = NULL; 353 bp->bio_offset = cp->provider->mediasize; 354 bp->bio_length = 0; 355 bp->bio_data = NULL; 356 g_io_request(bp, cp); 357 error = biowait(bp, "gflush"); 358 g_destroy_bio(bp); 359 return (error); 360 } 361 362 static int 363 g_io_check(struct bio *bp) 364 { 365 struct g_consumer *cp; 366 struct g_provider *pp; 367 off_t excess; 368 int error; 369 370 biotrack(bp, __func__); 371 372 cp = bp->bio_from; 373 pp = bp->bio_to; 374 375 /* Fail if access counters dont allow the operation */ 376 switch(bp->bio_cmd) { 377 case BIO_READ: 378 case BIO_GETATTR: 379 if (cp->acr == 0) 380 return (EPERM); 381 break; 382 case BIO_WRITE: 383 case BIO_DELETE: 384 case BIO_FLUSH: 385 if (cp->acw == 0) 386 return (EPERM); 387 break; 388 case BIO_ZONE: 389 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) || 390 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) { 391 if (cp->acr == 0) 392 return (EPERM); 393 } else if (cp->acw == 0) 394 return (EPERM); 395 break; 396 default: 397 return (EPERM); 398 } 399 /* if provider is marked for error, don't disturb. */ 400 if (pp->error) 401 return (pp->error); 402 if (cp->flags & G_CF_ORPHAN) 403 return (ENXIO); 404 405 switch(bp->bio_cmd) { 406 case BIO_READ: 407 case BIO_WRITE: 408 case BIO_DELETE: 409 /* Zero sectorsize or mediasize is probably a lack of media. */ 410 if (pp->sectorsize == 0 || pp->mediasize == 0) 411 return (ENXIO); 412 /* Reject I/O not on sector boundary */ 413 if (bp->bio_offset % pp->sectorsize) 414 return (EINVAL); 415 /* Reject I/O not integral sector long */ 416 if (bp->bio_length % pp->sectorsize) 417 return (EINVAL); 418 /* Reject requests before or past the end of media. */ 419 if (bp->bio_offset < 0) 420 return (EIO); 421 if (bp->bio_offset > pp->mediasize) 422 return (EIO); 423 424 /* Truncate requests to the end of providers media. */ 425 excess = bp->bio_offset + bp->bio_length; 426 if (excess > bp->bio_to->mediasize) { 427 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 || 428 round_page(bp->bio_ma_offset + 429 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n, 430 ("excess bio %p too short", bp)); 431 excess -= bp->bio_to->mediasize; 432 bp->bio_length -= excess; 433 if ((bp->bio_flags & BIO_UNMAPPED) != 0) { 434 bp->bio_ma_n = round_page(bp->bio_ma_offset + 435 bp->bio_length) / PAGE_SIZE; 436 } 437 if (excess > 0) 438 CTR3(KTR_GEOM, "g_down truncated bio " 439 "%p provider %s by %d", bp, 440 bp->bio_to->name, excess); 441 } 442 443 /* Deliver zero length transfers right here. */ 444 if (bp->bio_length == 0) { 445 CTR2(KTR_GEOM, "g_down terminated 0-length " 446 "bp %p provider %s", bp, bp->bio_to->name); 447 return (0); 448 } 449 450 if ((bp->bio_flags & BIO_UNMAPPED) != 0 && 451 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 && 452 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) { 453 if ((error = g_io_transient_map_bio(bp)) >= 0) 454 return (error); 455 } 456 break; 457 default: 458 break; 459 } 460 return (EJUSTRETURN); 461 } 462 463 /* 464 * bio classification support. 465 * 466 * g_register_classifier() and g_unregister_classifier() 467 * are used to add/remove a classifier from the list. 468 * The list is protected using the g_bio_run_down lock, 469 * because the classifiers are called in this path. 470 * 471 * g_io_request() passes bio's that are not already classified 472 * (i.e. those with bio_classifier1 == NULL) to g_run_classifiers(). 473 * Classifiers can store their result in the two fields 474 * bio_classifier1 and bio_classifier2. 475 * A classifier that updates one of the fields should 476 * return a non-zero value. 477 * If no classifier updates the field, g_run_classifiers() sets 478 * bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls. 479 */ 480 481 int 482 g_register_classifier(struct g_classifier_hook *hook) 483 { 484 485 g_bioq_lock(&g_bio_run_down); 486 TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link); 487 g_bioq_unlock(&g_bio_run_down); 488 489 return (0); 490 } 491 492 void 493 g_unregister_classifier(struct g_classifier_hook *hook) 494 { 495 struct g_classifier_hook *entry; 496 497 g_bioq_lock(&g_bio_run_down); 498 TAILQ_FOREACH(entry, &g_classifier_tailq, link) { 499 if (entry == hook) { 500 TAILQ_REMOVE(&g_classifier_tailq, hook, link); 501 break; 502 } 503 } 504 g_bioq_unlock(&g_bio_run_down); 505 } 506 507 static void 508 g_run_classifiers(struct bio *bp) 509 { 510 struct g_classifier_hook *hook; 511 int classified = 0; 512 513 biotrack(bp, __func__); 514 515 TAILQ_FOREACH(hook, &g_classifier_tailq, link) 516 classified |= hook->func(hook->arg, bp); 517 518 if (!classified) 519 bp->bio_classifier1 = BIO_NOTCLASSIFIED; 520 } 521 522 void 523 g_io_request(struct bio *bp, struct g_consumer *cp) 524 { 525 struct g_provider *pp; 526 struct mtx *mtxp; 527 int direct, error, first; 528 uint8_t cmd; 529 530 biotrack(bp, __func__); 531 532 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 533 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 534 pp = cp->provider; 535 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 536 #ifdef DIAGNOSTIC 537 KASSERT(bp->bio_driver1 == NULL, 538 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name)); 539 KASSERT(bp->bio_driver2 == NULL, 540 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name)); 541 KASSERT(bp->bio_pflags == 0, 542 ("bio_pflags used by the consumer (geom %s)", cp->geom->name)); 543 /* 544 * Remember consumer's private fields, so we can detect if they were 545 * modified by the provider. 546 */ 547 bp->_bio_caller1 = bp->bio_caller1; 548 bp->_bio_caller2 = bp->bio_caller2; 549 bp->_bio_cflags = bp->bio_cflags; 550 #endif 551 552 cmd = bp->bio_cmd; 553 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) { 554 KASSERT(bp->bio_data != NULL, 555 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd)); 556 } 557 if (cmd == BIO_DELETE || cmd == BIO_FLUSH) { 558 KASSERT(bp->bio_data == NULL, 559 ("non-NULL bp->data in g_io_request(cmd=%hu)", 560 bp->bio_cmd)); 561 } 562 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) { 563 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, 564 ("wrong offset %jd for sectorsize %u", 565 bp->bio_offset, cp->provider->sectorsize)); 566 KASSERT(bp->bio_length % cp->provider->sectorsize == 0, 567 ("wrong length %jd for sectorsize %u", 568 bp->bio_length, cp->provider->sectorsize)); 569 } 570 571 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 572 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 573 574 bp->bio_from = cp; 575 bp->bio_to = pp; 576 bp->bio_error = 0; 577 bp->bio_completed = 0; 578 579 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 580 ("Bio already on queue bp=%p", bp)); 581 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 582 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 583 binuptime(&bp->bio_t0); 584 else 585 getbinuptime(&bp->bio_t0); 586 587 #ifdef GET_STACK_USAGE 588 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 && 589 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 && 590 !g_is_geom_thread(curthread) && 591 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 || 592 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) && 593 pace == 0; 594 if (direct) { 595 /* Block direct execution if less then half of stack left. */ 596 size_t st, su; 597 GET_STACK_USAGE(st, su); 598 if (su * 2 > st) 599 direct = 0; 600 } 601 #else 602 direct = 0; 603 #endif 604 605 if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1) { 606 g_bioq_lock(&g_bio_run_down); 607 g_run_classifiers(bp); 608 g_bioq_unlock(&g_bio_run_down); 609 } 610 611 /* 612 * The statistics collection is lockless, as such, but we 613 * can not update one instance of the statistics from more 614 * than one thread at a time, so grab the lock first. 615 */ 616 mtxp = mtx_pool_find(mtxpool_sleep, pp); 617 mtx_lock(mtxp); 618 if (g_collectstats & G_STATS_PROVIDERS) 619 devstat_start_transaction(pp->stat, &bp->bio_t0); 620 if (g_collectstats & G_STATS_CONSUMERS) 621 devstat_start_transaction(cp->stat, &bp->bio_t0); 622 pp->nstart++; 623 cp->nstart++; 624 mtx_unlock(mtxp); 625 626 if (direct) { 627 error = g_io_check(bp); 628 if (error >= 0) { 629 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p " 630 "provider %s returned %d", bp, bp->bio_to->name, 631 error); 632 g_io_deliver(bp, error); 633 return; 634 } 635 bp->bio_to->geom->start(bp); 636 } else { 637 g_bioq_lock(&g_bio_run_down); 638 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue); 639 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue); 640 bp->bio_flags |= BIO_ONQUEUE; 641 g_bio_run_down.bio_queue_length++; 642 g_bioq_unlock(&g_bio_run_down); 643 /* Pass it on down. */ 644 if (first) 645 wakeup(&g_wait_down); 646 } 647 } 648 649 void 650 g_io_deliver(struct bio *bp, int error) 651 { 652 struct bintime now; 653 struct g_consumer *cp; 654 struct g_provider *pp; 655 struct mtx *mtxp; 656 int direct, first; 657 658 biotrack(bp, __func__); 659 660 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 661 pp = bp->bio_to; 662 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 663 cp = bp->bio_from; 664 if (cp == NULL) { 665 bp->bio_error = error; 666 bp->bio_done(bp); 667 return; 668 } 669 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 670 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 671 #ifdef DIAGNOSTIC 672 /* 673 * Some classes - GJournal in particular - can modify bio's 674 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO 675 * flag means it's an expected behaviour for that particular geom. 676 */ 677 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) { 678 KASSERT(bp->bio_caller1 == bp->_bio_caller1, 679 ("bio_caller1 used by the provider %s", pp->name)); 680 KASSERT(bp->bio_caller2 == bp->_bio_caller2, 681 ("bio_caller2 used by the provider %s", pp->name)); 682 KASSERT(bp->bio_cflags == bp->_bio_cflags, 683 ("bio_cflags used by the provider %s", pp->name)); 684 } 685 #endif 686 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 687 KASSERT(bp->bio_completed <= bp->bio_length, 688 ("bio_completed can't be greater than bio_length")); 689 690 g_trace(G_T_BIO, 691 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 692 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 693 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 694 695 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 696 ("Bio already on queue bp=%p", bp)); 697 698 /* 699 * XXX: next two doesn't belong here 700 */ 701 bp->bio_bcount = bp->bio_length; 702 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 703 704 #ifdef GET_STACK_USAGE 705 direct = (pp->flags & G_PF_DIRECT_SEND) && 706 (cp->flags & G_CF_DIRECT_RECEIVE) && 707 !g_is_geom_thread(curthread); 708 if (direct) { 709 /* Block direct execution if less then half of stack left. */ 710 size_t st, su; 711 GET_STACK_USAGE(st, su); 712 if (su * 2 > st) 713 direct = 0; 714 } 715 #else 716 direct = 0; 717 #endif 718 719 /* 720 * The statistics collection is lockless, as such, but we 721 * can not update one instance of the statistics from more 722 * than one thread at a time, so grab the lock first. 723 */ 724 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 725 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 726 binuptime(&now); 727 mtxp = mtx_pool_find(mtxpool_sleep, cp); 728 mtx_lock(mtxp); 729 if (g_collectstats & G_STATS_PROVIDERS) 730 devstat_end_transaction_bio_bt(pp->stat, bp, &now); 731 if (g_collectstats & G_STATS_CONSUMERS) 732 devstat_end_transaction_bio_bt(cp->stat, bp, &now); 733 cp->nend++; 734 pp->nend++; 735 mtx_unlock(mtxp); 736 737 if (error != ENOMEM) { 738 bp->bio_error = error; 739 if (direct) { 740 biodone(bp); 741 } else { 742 g_bioq_lock(&g_bio_run_up); 743 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue); 744 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue); 745 bp->bio_flags |= BIO_ONQUEUE; 746 g_bio_run_up.bio_queue_length++; 747 g_bioq_unlock(&g_bio_run_up); 748 if (first) 749 wakeup(&g_wait_up); 750 } 751 return; 752 } 753 754 if (bootverbose) 755 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 756 bp->bio_children = 0; 757 bp->bio_inbed = 0; 758 bp->bio_driver1 = NULL; 759 bp->bio_driver2 = NULL; 760 bp->bio_pflags = 0; 761 g_io_request(bp, cp); 762 pace = 1; 763 return; 764 } 765 766 SYSCTL_DECL(_kern_geom); 767 768 static long transient_maps; 769 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD, 770 &transient_maps, 0, 771 "Total count of the transient mapping requests"); 772 u_int transient_map_retries = 10; 773 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW, 774 &transient_map_retries, 0, 775 "Max count of retries used before giving up on creating transient map"); 776 int transient_map_hard_failures; 777 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD, 778 &transient_map_hard_failures, 0, 779 "Failures to establish the transient mapping due to retry attempts " 780 "exhausted"); 781 int transient_map_soft_failures; 782 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD, 783 &transient_map_soft_failures, 0, 784 "Count of retried failures to establish the transient mapping"); 785 int inflight_transient_maps; 786 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD, 787 &inflight_transient_maps, 0, 788 "Current count of the active transient maps"); 789 790 static int 791 g_io_transient_map_bio(struct bio *bp) 792 { 793 vm_offset_t addr; 794 long size; 795 u_int retried; 796 797 KASSERT(unmapped_buf_allowed, ("unmapped disabled")); 798 799 size = round_page(bp->bio_ma_offset + bp->bio_length); 800 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp)); 801 addr = 0; 802 retried = 0; 803 atomic_add_long(&transient_maps, 1); 804 retry: 805 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) { 806 if (transient_map_retries != 0 && 807 retried >= transient_map_retries) { 808 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s", 809 bp, bp->bio_to->name); 810 atomic_add_int(&transient_map_hard_failures, 1); 811 return (EDEADLK/* XXXKIB */); 812 } else { 813 /* 814 * Naive attempt to quisce the I/O to get more 815 * in-flight requests completed and defragment 816 * the transient_arena. 817 */ 818 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d", 819 bp, bp->bio_to->name, retried); 820 pause("g_d_tra", hz / 10); 821 retried++; 822 atomic_add_int(&transient_map_soft_failures, 1); 823 goto retry; 824 } 825 } 826 atomic_add_int(&inflight_transient_maps, 1); 827 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size)); 828 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset; 829 bp->bio_flags |= BIO_TRANSIENT_MAPPING; 830 bp->bio_flags &= ~BIO_UNMAPPED; 831 return (EJUSTRETURN); 832 } 833 834 void 835 g_io_schedule_down(struct thread *tp __unused) 836 { 837 struct bio *bp; 838 int error; 839 840 for(;;) { 841 g_bioq_lock(&g_bio_run_down); 842 bp = g_bioq_first(&g_bio_run_down); 843 if (bp == NULL) { 844 CTR0(KTR_GEOM, "g_down going to sleep"); 845 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 846 PRIBIO | PDROP, "-", 0); 847 continue; 848 } 849 CTR0(KTR_GEOM, "g_down has work to do"); 850 g_bioq_unlock(&g_bio_run_down); 851 biotrack(bp, __func__); 852 if (pace != 0) { 853 /* 854 * There has been at least one memory allocation 855 * failure since the last I/O completed. Pause 1ms to 856 * give the system a chance to free up memory. We only 857 * do this once because a large number of allocations 858 * can fail in the direct dispatch case and there's no 859 * relationship between the number of these failures and 860 * the length of the outage. If there's still an outage, 861 * we'll pause again and again until it's 862 * resolved. Older versions paused longer and once per 863 * allocation failure. This was OK for a single threaded 864 * g_down, but with direct dispatch would lead to max of 865 * 10 IOPs for minutes at a time when transient memory 866 * issues prevented allocation for a batch of requests 867 * from the upper layers. 868 * 869 * XXX This pacing is really lame. It needs to be solved 870 * by other methods. This is OK only because the worst 871 * case scenario is so rare. In the worst case scenario 872 * all memory is tied up waiting for I/O to complete 873 * which can never happen since we can't allocate bios 874 * for that I/O. 875 */ 876 CTR0(KTR_GEOM, "g_down pacing self"); 877 pause("g_down", min(hz/1000, 1)); 878 pace = 0; 879 } 880 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp, 881 bp->bio_to->name); 882 error = g_io_check(bp); 883 if (error >= 0) { 884 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider " 885 "%s returned %d", bp, bp->bio_to->name, error); 886 g_io_deliver(bp, error); 887 continue; 888 } 889 THREAD_NO_SLEEPING(); 890 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld " 891 "len %ld", bp, bp->bio_to->name, bp->bio_offset, 892 bp->bio_length); 893 bp->bio_to->geom->start(bp); 894 THREAD_SLEEPING_OK(); 895 } 896 } 897 898 void 899 g_io_schedule_up(struct thread *tp __unused) 900 { 901 struct bio *bp; 902 903 for(;;) { 904 g_bioq_lock(&g_bio_run_up); 905 bp = g_bioq_first(&g_bio_run_up); 906 if (bp == NULL) { 907 CTR0(KTR_GEOM, "g_up going to sleep"); 908 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 909 PRIBIO | PDROP, "-", 0); 910 continue; 911 } 912 g_bioq_unlock(&g_bio_run_up); 913 THREAD_NO_SLEEPING(); 914 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off " 915 "%jd len %ld", bp, bp->bio_to->name, 916 bp->bio_offset, bp->bio_length); 917 biodone(bp); 918 THREAD_SLEEPING_OK(); 919 } 920 } 921 922 void * 923 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 924 { 925 struct bio *bp; 926 void *ptr; 927 int errorc; 928 929 KASSERT(length > 0 && length >= cp->provider->sectorsize && 930 length <= MAXPHYS, ("g_read_data(): invalid length %jd", 931 (intmax_t)length)); 932 933 bp = g_alloc_bio(); 934 bp->bio_cmd = BIO_READ; 935 bp->bio_done = NULL; 936 bp->bio_offset = offset; 937 bp->bio_length = length; 938 ptr = g_malloc(length, M_WAITOK); 939 bp->bio_data = ptr; 940 g_io_request(bp, cp); 941 errorc = biowait(bp, "gread"); 942 if (error != NULL) 943 *error = errorc; 944 g_destroy_bio(bp); 945 if (errorc) { 946 g_free(ptr); 947 ptr = NULL; 948 } 949 return (ptr); 950 } 951 952 /* 953 * A read function for use by ffs_sbget when used by GEOM-layer routines. 954 */ 955 int 956 g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size) 957 { 958 struct g_consumer *cp; 959 960 KASSERT(*bufp == NULL, 961 ("g_use_g_read_data: non-NULL *bufp %p\n", *bufp)); 962 963 cp = (struct g_consumer *)devfd; 964 /* 965 * Take care not to issue an invalid I/O request. The offset of 966 * the superblock candidate must be multiples of the provider's 967 * sector size, otherwise an FFS can't exist on the provider 968 * anyway. 969 */ 970 if (loc % cp->provider->sectorsize != 0) 971 return (ENOENT); 972 *bufp = g_read_data(cp, loc, size, NULL); 973 if (*bufp == NULL) 974 return (ENOENT); 975 return (0); 976 } 977 978 int 979 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 980 { 981 struct bio *bp; 982 int error; 983 984 KASSERT(length > 0 && length >= cp->provider->sectorsize && 985 length <= MAXPHYS, ("g_write_data(): invalid length %jd", 986 (intmax_t)length)); 987 988 bp = g_alloc_bio(); 989 bp->bio_cmd = BIO_WRITE; 990 bp->bio_done = NULL; 991 bp->bio_offset = offset; 992 bp->bio_length = length; 993 bp->bio_data = ptr; 994 g_io_request(bp, cp); 995 error = biowait(bp, "gwrite"); 996 g_destroy_bio(bp); 997 return (error); 998 } 999 1000 /* 1001 * A write function for use by ffs_sbput when used by GEOM-layer routines. 1002 */ 1003 int 1004 g_use_g_write_data(void *devfd, off_t loc, void *buf, int size) 1005 { 1006 1007 return (g_write_data((struct g_consumer *)devfd, loc, buf, size)); 1008 } 1009 1010 int 1011 g_delete_data(struct g_consumer *cp, off_t offset, off_t length) 1012 { 1013 struct bio *bp; 1014 int error; 1015 1016 KASSERT(length > 0 && length >= cp->provider->sectorsize, 1017 ("g_delete_data(): invalid length %jd", (intmax_t)length)); 1018 1019 bp = g_alloc_bio(); 1020 bp->bio_cmd = BIO_DELETE; 1021 bp->bio_done = NULL; 1022 bp->bio_offset = offset; 1023 bp->bio_length = length; 1024 bp->bio_data = NULL; 1025 g_io_request(bp, cp); 1026 error = biowait(bp, "gdelete"); 1027 g_destroy_bio(bp); 1028 return (error); 1029 } 1030 1031 void 1032 g_print_bio(struct bio *bp) 1033 { 1034 const char *pname, *cmd = NULL; 1035 1036 if (bp->bio_to != NULL) 1037 pname = bp->bio_to->name; 1038 else 1039 pname = "[unknown]"; 1040 1041 switch (bp->bio_cmd) { 1042 case BIO_GETATTR: 1043 cmd = "GETATTR"; 1044 printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute); 1045 return; 1046 case BIO_FLUSH: 1047 cmd = "FLUSH"; 1048 printf("%s[%s]", pname, cmd); 1049 return; 1050 case BIO_ZONE: { 1051 char *subcmd = NULL; 1052 cmd = "ZONE"; 1053 switch (bp->bio_zone.zone_cmd) { 1054 case DISK_ZONE_OPEN: 1055 subcmd = "OPEN"; 1056 break; 1057 case DISK_ZONE_CLOSE: 1058 subcmd = "CLOSE"; 1059 break; 1060 case DISK_ZONE_FINISH: 1061 subcmd = "FINISH"; 1062 break; 1063 case DISK_ZONE_RWP: 1064 subcmd = "RWP"; 1065 break; 1066 case DISK_ZONE_REPORT_ZONES: 1067 subcmd = "REPORT ZONES"; 1068 break; 1069 case DISK_ZONE_GET_PARAMS: 1070 subcmd = "GET PARAMS"; 1071 break; 1072 default: 1073 subcmd = "UNKNOWN"; 1074 break; 1075 } 1076 printf("%s[%s,%s]", pname, cmd, subcmd); 1077 return; 1078 } 1079 case BIO_READ: 1080 cmd = "READ"; 1081 break; 1082 case BIO_WRITE: 1083 cmd = "WRITE"; 1084 break; 1085 case BIO_DELETE: 1086 cmd = "DELETE"; 1087 break; 1088 default: 1089 cmd = "UNKNOWN"; 1090 printf("%s[%s()]", pname, cmd); 1091 return; 1092 } 1093 printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd, 1094 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 1095 } 1096