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 /* 91 * The head of the list of classifiers used in g_io_request. 92 * Use g_register_classifier() and g_unregister_classifier() 93 * to add/remove entries to the list. 94 * Classifiers are invoked in registration order. 95 */ 96 static TAILQ_HEAD(, g_classifier_hook) g_classifier_tailq __read_mostly = 97 TAILQ_HEAD_INITIALIZER(g_classifier_tailq); 98 99 #include <machine/atomic.h> 100 101 static void 102 g_bioq_lock(struct g_bioq *bq) 103 { 104 105 mtx_lock(&bq->bio_queue_lock); 106 } 107 108 static void 109 g_bioq_unlock(struct g_bioq *bq) 110 { 111 112 mtx_unlock(&bq->bio_queue_lock); 113 } 114 115 #if 0 116 static void 117 g_bioq_destroy(struct g_bioq *bq) 118 { 119 120 mtx_destroy(&bq->bio_queue_lock); 121 } 122 #endif 123 124 static void 125 g_bioq_init(struct g_bioq *bq) 126 { 127 128 TAILQ_INIT(&bq->bio_queue); 129 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 130 } 131 132 static struct bio * 133 g_bioq_first(struct g_bioq *bq) 134 { 135 struct bio *bp; 136 137 bp = TAILQ_FIRST(&bq->bio_queue); 138 if (bp != NULL) { 139 KASSERT((bp->bio_flags & BIO_ONQUEUE), 140 ("Bio not on queue bp=%p target %p", bp, bq)); 141 bp->bio_flags &= ~BIO_ONQUEUE; 142 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 143 bq->bio_queue_length--; 144 } 145 return (bp); 146 } 147 148 struct bio * 149 g_new_bio(void) 150 { 151 struct bio *bp; 152 153 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 154 #ifdef KTR 155 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 156 struct stack st; 157 158 CTR1(KTR_GEOM, "g_new_bio(): %p", bp); 159 stack_save(&st); 160 CTRSTACK(KTR_GEOM, &st, 3); 161 } 162 #endif 163 return (bp); 164 } 165 166 struct bio * 167 g_alloc_bio(void) 168 { 169 struct bio *bp; 170 171 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); 172 #ifdef KTR 173 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 174 struct stack st; 175 176 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp); 177 stack_save(&st); 178 CTRSTACK(KTR_GEOM, &st, 3); 179 } 180 #endif 181 return (bp); 182 } 183 184 void 185 g_destroy_bio(struct bio *bp) 186 { 187 #ifdef KTR 188 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 189 struct stack st; 190 191 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp); 192 stack_save(&st); 193 CTRSTACK(KTR_GEOM, &st, 3); 194 } 195 #endif 196 uma_zfree(biozone, bp); 197 } 198 199 struct bio * 200 g_clone_bio(struct bio *bp) 201 { 202 struct bio *bp2; 203 204 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 205 if (bp2 != NULL) { 206 bp2->bio_parent = bp; 207 bp2->bio_cmd = bp->bio_cmd; 208 /* 209 * BIO_ORDERED flag may be used by disk drivers to enforce 210 * ordering restrictions, so this flag needs to be cloned. 211 * BIO_UNMAPPED and BIO_VLIST should be inherited, to properly 212 * indicate which way the buffer is passed. 213 * Other bio flags are not suitable for cloning. 214 */ 215 bp2->bio_flags = bp->bio_flags & 216 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST); 217 bp2->bio_length = bp->bio_length; 218 bp2->bio_offset = bp->bio_offset; 219 bp2->bio_data = bp->bio_data; 220 bp2->bio_ma = bp->bio_ma; 221 bp2->bio_ma_n = bp->bio_ma_n; 222 bp2->bio_ma_offset = bp->bio_ma_offset; 223 bp2->bio_attribute = bp->bio_attribute; 224 if (bp->bio_cmd == BIO_ZONE) 225 bcopy(&bp->bio_zone, &bp2->bio_zone, 226 sizeof(bp->bio_zone)); 227 /* Inherit classification info from the parent */ 228 bp2->bio_classifier1 = bp->bio_classifier1; 229 bp2->bio_classifier2 = bp->bio_classifier2; 230 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 231 bp2->bio_track_bp = bp->bio_track_bp; 232 #endif 233 bp->bio_children++; 234 } 235 #ifdef KTR 236 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 237 struct stack st; 238 239 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2); 240 stack_save(&st); 241 CTRSTACK(KTR_GEOM, &st, 3); 242 } 243 #endif 244 return(bp2); 245 } 246 247 struct bio * 248 g_duplicate_bio(struct bio *bp) 249 { 250 struct bio *bp2; 251 252 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO); 253 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST); 254 bp2->bio_parent = bp; 255 bp2->bio_cmd = bp->bio_cmd; 256 bp2->bio_length = bp->bio_length; 257 bp2->bio_offset = bp->bio_offset; 258 bp2->bio_data = bp->bio_data; 259 bp2->bio_ma = bp->bio_ma; 260 bp2->bio_ma_n = bp->bio_ma_n; 261 bp2->bio_ma_offset = bp->bio_ma_offset; 262 bp2->bio_attribute = bp->bio_attribute; 263 bp->bio_children++; 264 #ifdef KTR 265 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 266 struct stack st; 267 268 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2); 269 stack_save(&st); 270 CTRSTACK(KTR_GEOM, &st, 3); 271 } 272 #endif 273 return(bp2); 274 } 275 276 void 277 g_reset_bio(struct bio *bp) 278 { 279 280 bzero(bp, sizeof(*bp)); 281 } 282 283 void 284 g_io_init() 285 { 286 287 g_bioq_init(&g_bio_run_down); 288 g_bioq_init(&g_bio_run_up); 289 biozone = uma_zcreate("g_bio", sizeof (struct bio), 290 NULL, NULL, 291 NULL, NULL, 292 0, 0); 293 } 294 295 int 296 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 297 { 298 struct bio *bp; 299 int error; 300 301 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 302 bp = g_alloc_bio(); 303 bp->bio_cmd = BIO_GETATTR; 304 bp->bio_done = NULL; 305 bp->bio_attribute = attr; 306 bp->bio_length = *len; 307 bp->bio_data = ptr; 308 g_io_request(bp, cp); 309 error = biowait(bp, "ggetattr"); 310 *len = bp->bio_completed; 311 g_destroy_bio(bp); 312 return (error); 313 } 314 315 int 316 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp) 317 { 318 struct bio *bp; 319 int error; 320 321 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd); 322 bp = g_alloc_bio(); 323 bp->bio_cmd = BIO_ZONE; 324 bp->bio_done = NULL; 325 /* 326 * XXX KDM need to handle report zone data. 327 */ 328 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args)); 329 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) 330 bp->bio_length = 331 zone_args->zone_params.report.entries_allocated * 332 sizeof(struct disk_zone_rep_entry); 333 else 334 bp->bio_length = 0; 335 336 g_io_request(bp, cp); 337 error = biowait(bp, "gzone"); 338 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args)); 339 g_destroy_bio(bp); 340 return (error); 341 } 342 343 /* 344 * Send a BIO_SPEEDUP down the stack. This is used to tell the lower layers that 345 * the upper layers have detected a resource shortage. The lower layers are 346 * advised to stop delaying I/O that they might be holding for performance 347 * reasons and to schedule it (non-trims) or complete it successfully (trims) as 348 * quickly as it can. bio_length is the amount of the shortage. This call 349 * should be non-blocking. bio_resid is used to communicate back if the lower 350 * layers couldn't find bio_length worth of I/O to schedule or discard. A length 351 * of 0 means to do as much as you can (schedule the h/w queues full, discard 352 * all trims). flags are a hint from the upper layers to the lower layers what 353 * operation should be done. 354 */ 355 int 356 g_io_speedup(size_t shortage, u_int flags, size_t *resid, struct g_consumer *cp) 357 { 358 struct bio *bp; 359 int error; 360 361 KASSERT((flags & (BIO_SPEEDUP_TRIM | BIO_SPEEDUP_WRITE)) != 0, 362 ("Invalid flags passed to g_io_speedup: %#x", flags)); 363 g_trace(G_T_BIO, "bio_speedup(%s, %zu, %#x)", cp->provider->name, 364 shortage, flags); 365 bp = g_new_bio(); 366 if (bp == NULL) 367 return (ENOMEM); 368 bp->bio_cmd = BIO_SPEEDUP; 369 bp->bio_length = shortage; 370 bp->bio_done = NULL; 371 bp->bio_flags |= flags; 372 g_io_request(bp, cp); 373 error = biowait(bp, "gflush"); 374 *resid = bp->bio_resid; 375 g_destroy_bio(bp); 376 return (error); 377 } 378 379 int 380 g_io_flush(struct g_consumer *cp) 381 { 382 struct bio *bp; 383 int error; 384 385 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name); 386 bp = g_alloc_bio(); 387 bp->bio_cmd = BIO_FLUSH; 388 bp->bio_flags |= BIO_ORDERED; 389 bp->bio_done = NULL; 390 bp->bio_attribute = NULL; 391 bp->bio_offset = cp->provider->mediasize; 392 bp->bio_length = 0; 393 bp->bio_data = NULL; 394 g_io_request(bp, cp); 395 error = biowait(bp, "gflush"); 396 g_destroy_bio(bp); 397 return (error); 398 } 399 400 static int 401 g_io_check(struct bio *bp) 402 { 403 struct g_consumer *cp; 404 struct g_provider *pp; 405 off_t excess; 406 int error; 407 408 biotrack(bp, __func__); 409 410 cp = bp->bio_from; 411 pp = bp->bio_to; 412 413 /* Fail if access counters dont allow the operation */ 414 switch(bp->bio_cmd) { 415 case BIO_READ: 416 case BIO_GETATTR: 417 if (cp->acr == 0) 418 return (EPERM); 419 break; 420 case BIO_WRITE: 421 case BIO_DELETE: 422 case BIO_FLUSH: 423 if (cp->acw == 0) 424 return (EPERM); 425 break; 426 case BIO_ZONE: 427 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) || 428 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) { 429 if (cp->acr == 0) 430 return (EPERM); 431 } else if (cp->acw == 0) 432 return (EPERM); 433 break; 434 default: 435 return (EPERM); 436 } 437 /* if provider is marked for error, don't disturb. */ 438 if (pp->error) 439 return (pp->error); 440 if (cp->flags & G_CF_ORPHAN) 441 return (ENXIO); 442 443 switch(bp->bio_cmd) { 444 case BIO_READ: 445 case BIO_WRITE: 446 case BIO_DELETE: 447 /* Zero sectorsize or mediasize is probably a lack of media. */ 448 if (pp->sectorsize == 0 || pp->mediasize == 0) 449 return (ENXIO); 450 /* Reject I/O not on sector boundary */ 451 if (bp->bio_offset % pp->sectorsize) 452 return (EINVAL); 453 /* Reject I/O not integral sector long */ 454 if (bp->bio_length % pp->sectorsize) 455 return (EINVAL); 456 /* Reject requests before or past the end of media. */ 457 if (bp->bio_offset < 0) 458 return (EIO); 459 if (bp->bio_offset > pp->mediasize) 460 return (EIO); 461 462 /* Truncate requests to the end of providers media. */ 463 excess = bp->bio_offset + bp->bio_length; 464 if (excess > bp->bio_to->mediasize) { 465 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 || 466 round_page(bp->bio_ma_offset + 467 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n, 468 ("excess bio %p too short", bp)); 469 excess -= bp->bio_to->mediasize; 470 bp->bio_length -= excess; 471 if ((bp->bio_flags & BIO_UNMAPPED) != 0) { 472 bp->bio_ma_n = round_page(bp->bio_ma_offset + 473 bp->bio_length) / PAGE_SIZE; 474 } 475 if (excess > 0) 476 CTR3(KTR_GEOM, "g_down truncated bio " 477 "%p provider %s by %d", bp, 478 bp->bio_to->name, excess); 479 } 480 481 /* Deliver zero length transfers right here. */ 482 if (bp->bio_length == 0) { 483 CTR2(KTR_GEOM, "g_down terminated 0-length " 484 "bp %p provider %s", bp, bp->bio_to->name); 485 return (0); 486 } 487 488 if ((bp->bio_flags & BIO_UNMAPPED) != 0 && 489 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 && 490 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) { 491 if ((error = g_io_transient_map_bio(bp)) >= 0) 492 return (error); 493 } 494 break; 495 default: 496 break; 497 } 498 return (EJUSTRETURN); 499 } 500 501 /* 502 * bio classification support. 503 * 504 * g_register_classifier() and g_unregister_classifier() 505 * are used to add/remove a classifier from the list. 506 * The list is protected using the g_bio_run_down lock, 507 * because the classifiers are called in this path. 508 * 509 * g_io_request() passes bio's that are not already classified 510 * (i.e. those with bio_classifier1 == NULL) to g_run_classifiers(). 511 * Classifiers can store their result in the two fields 512 * bio_classifier1 and bio_classifier2. 513 * A classifier that updates one of the fields should 514 * return a non-zero value. 515 * If no classifier updates the field, g_run_classifiers() sets 516 * bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls. 517 */ 518 519 int 520 g_register_classifier(struct g_classifier_hook *hook) 521 { 522 523 g_bioq_lock(&g_bio_run_down); 524 TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link); 525 g_bioq_unlock(&g_bio_run_down); 526 527 return (0); 528 } 529 530 void 531 g_unregister_classifier(struct g_classifier_hook *hook) 532 { 533 struct g_classifier_hook *entry; 534 535 g_bioq_lock(&g_bio_run_down); 536 TAILQ_FOREACH(entry, &g_classifier_tailq, link) { 537 if (entry == hook) { 538 TAILQ_REMOVE(&g_classifier_tailq, hook, link); 539 break; 540 } 541 } 542 g_bioq_unlock(&g_bio_run_down); 543 } 544 545 static void 546 g_run_classifiers(struct bio *bp) 547 { 548 struct g_classifier_hook *hook; 549 int classified = 0; 550 551 biotrack(bp, __func__); 552 553 TAILQ_FOREACH(hook, &g_classifier_tailq, link) 554 classified |= hook->func(hook->arg, bp); 555 556 if (!classified) 557 bp->bio_classifier1 = BIO_NOTCLASSIFIED; 558 } 559 560 void 561 g_io_request(struct bio *bp, struct g_consumer *cp) 562 { 563 struct g_provider *pp; 564 struct mtx *mtxp; 565 int direct, error, first; 566 uint8_t cmd; 567 568 biotrack(bp, __func__); 569 570 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 571 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 572 pp = cp->provider; 573 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 574 #ifdef DIAGNOSTIC 575 KASSERT(bp->bio_driver1 == NULL, 576 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name)); 577 KASSERT(bp->bio_driver2 == NULL, 578 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name)); 579 KASSERT(bp->bio_pflags == 0, 580 ("bio_pflags used by the consumer (geom %s)", cp->geom->name)); 581 /* 582 * Remember consumer's private fields, so we can detect if they were 583 * modified by the provider. 584 */ 585 bp->_bio_caller1 = bp->bio_caller1; 586 bp->_bio_caller2 = bp->bio_caller2; 587 bp->_bio_cflags = bp->bio_cflags; 588 #endif 589 590 cmd = bp->bio_cmd; 591 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) { 592 KASSERT(bp->bio_data != NULL, 593 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd)); 594 } 595 if (cmd == BIO_DELETE || cmd == BIO_FLUSH) { 596 KASSERT(bp->bio_data == NULL, 597 ("non-NULL bp->data in g_io_request(cmd=%hu)", 598 bp->bio_cmd)); 599 } 600 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) { 601 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, 602 ("wrong offset %jd for sectorsize %u", 603 bp->bio_offset, cp->provider->sectorsize)); 604 KASSERT(bp->bio_length % cp->provider->sectorsize == 0, 605 ("wrong length %jd for sectorsize %u", 606 bp->bio_length, cp->provider->sectorsize)); 607 } 608 609 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 610 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 611 612 bp->bio_from = cp; 613 bp->bio_to = pp; 614 bp->bio_error = 0; 615 bp->bio_completed = 0; 616 617 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 618 ("Bio already on queue bp=%p", bp)); 619 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 620 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 621 binuptime(&bp->bio_t0); 622 else 623 getbinuptime(&bp->bio_t0); 624 625 #ifdef GET_STACK_USAGE 626 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 && 627 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 && 628 !g_is_geom_thread(curthread) && 629 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 || 630 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) && 631 pace == 0; 632 if (direct) { 633 /* Block direct execution if less then half of stack left. */ 634 size_t st, su; 635 GET_STACK_USAGE(st, su); 636 if (su * 2 > st) 637 direct = 0; 638 } 639 #else 640 direct = 0; 641 #endif 642 643 if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1) { 644 g_bioq_lock(&g_bio_run_down); 645 g_run_classifiers(bp); 646 g_bioq_unlock(&g_bio_run_down); 647 } 648 649 /* 650 * The statistics collection is lockless, as such, but we 651 * can not update one instance of the statistics from more 652 * than one thread at a time, so grab the lock first. 653 */ 654 mtxp = mtx_pool_find(mtxpool_sleep, pp); 655 mtx_lock(mtxp); 656 if (g_collectstats & G_STATS_PROVIDERS) 657 devstat_start_transaction(pp->stat, &bp->bio_t0); 658 if (g_collectstats & G_STATS_CONSUMERS) 659 devstat_start_transaction(cp->stat, &bp->bio_t0); 660 pp->nstart++; 661 cp->nstart++; 662 mtx_unlock(mtxp); 663 664 if (direct) { 665 error = g_io_check(bp); 666 if (error >= 0) { 667 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p " 668 "provider %s returned %d", bp, bp->bio_to->name, 669 error); 670 g_io_deliver(bp, error); 671 return; 672 } 673 bp->bio_to->geom->start(bp); 674 } else { 675 g_bioq_lock(&g_bio_run_down); 676 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue); 677 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue); 678 bp->bio_flags |= BIO_ONQUEUE; 679 g_bio_run_down.bio_queue_length++; 680 g_bioq_unlock(&g_bio_run_down); 681 /* Pass it on down. */ 682 if (first) 683 wakeup(&g_wait_down); 684 } 685 } 686 687 void 688 g_io_deliver(struct bio *bp, int error) 689 { 690 struct bintime now; 691 struct g_consumer *cp; 692 struct g_provider *pp; 693 struct mtx *mtxp; 694 int direct, first; 695 696 biotrack(bp, __func__); 697 698 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 699 pp = bp->bio_to; 700 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 701 cp = bp->bio_from; 702 if (cp == NULL) { 703 bp->bio_error = error; 704 bp->bio_done(bp); 705 return; 706 } 707 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 708 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 709 #ifdef DIAGNOSTIC 710 /* 711 * Some classes - GJournal in particular - can modify bio's 712 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO 713 * flag means it's an expected behaviour for that particular geom. 714 */ 715 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) { 716 KASSERT(bp->bio_caller1 == bp->_bio_caller1, 717 ("bio_caller1 used by the provider %s", pp->name)); 718 KASSERT(bp->bio_caller2 == bp->_bio_caller2, 719 ("bio_caller2 used by the provider %s", pp->name)); 720 KASSERT(bp->bio_cflags == bp->_bio_cflags, 721 ("bio_cflags used by the provider %s", pp->name)); 722 } 723 #endif 724 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 725 KASSERT(bp->bio_completed <= bp->bio_length, 726 ("bio_completed can't be greater than bio_length")); 727 728 g_trace(G_T_BIO, 729 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 730 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 731 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 732 733 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 734 ("Bio already on queue bp=%p", bp)); 735 736 /* 737 * XXX: next two doesn't belong here 738 */ 739 bp->bio_bcount = bp->bio_length; 740 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 741 742 #ifdef GET_STACK_USAGE 743 direct = (pp->flags & G_PF_DIRECT_SEND) && 744 (cp->flags & G_CF_DIRECT_RECEIVE) && 745 !g_is_geom_thread(curthread); 746 if (direct) { 747 /* Block direct execution if less then half of stack left. */ 748 size_t st, su; 749 GET_STACK_USAGE(st, su); 750 if (su * 2 > st) 751 direct = 0; 752 } 753 #else 754 direct = 0; 755 #endif 756 757 /* 758 * The statistics collection is lockless, as such, but we 759 * can not update one instance of the statistics from more 760 * than one thread at a time, so grab the lock first. 761 */ 762 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 763 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 764 binuptime(&now); 765 mtxp = mtx_pool_find(mtxpool_sleep, cp); 766 mtx_lock(mtxp); 767 if (g_collectstats & G_STATS_PROVIDERS) 768 devstat_end_transaction_bio_bt(pp->stat, bp, &now); 769 if (g_collectstats & G_STATS_CONSUMERS) 770 devstat_end_transaction_bio_bt(cp->stat, bp, &now); 771 cp->nend++; 772 pp->nend++; 773 mtx_unlock(mtxp); 774 775 if (error != ENOMEM) { 776 bp->bio_error = error; 777 if (direct) { 778 biodone(bp); 779 } else { 780 g_bioq_lock(&g_bio_run_up); 781 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue); 782 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue); 783 bp->bio_flags |= BIO_ONQUEUE; 784 g_bio_run_up.bio_queue_length++; 785 g_bioq_unlock(&g_bio_run_up); 786 if (first) 787 wakeup(&g_wait_up); 788 } 789 return; 790 } 791 792 if (bootverbose) 793 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 794 bp->bio_children = 0; 795 bp->bio_inbed = 0; 796 bp->bio_driver1 = NULL; 797 bp->bio_driver2 = NULL; 798 bp->bio_pflags = 0; 799 g_io_request(bp, cp); 800 pace = 1; 801 return; 802 } 803 804 SYSCTL_DECL(_kern_geom); 805 806 static long transient_maps; 807 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD, 808 &transient_maps, 0, 809 "Total count of the transient mapping requests"); 810 u_int transient_map_retries = 10; 811 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW, 812 &transient_map_retries, 0, 813 "Max count of retries used before giving up on creating transient map"); 814 int transient_map_hard_failures; 815 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD, 816 &transient_map_hard_failures, 0, 817 "Failures to establish the transient mapping due to retry attempts " 818 "exhausted"); 819 int transient_map_soft_failures; 820 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD, 821 &transient_map_soft_failures, 0, 822 "Count of retried failures to establish the transient mapping"); 823 int inflight_transient_maps; 824 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD, 825 &inflight_transient_maps, 0, 826 "Current count of the active transient maps"); 827 828 static int 829 g_io_transient_map_bio(struct bio *bp) 830 { 831 vm_offset_t addr; 832 long size; 833 u_int retried; 834 835 KASSERT(unmapped_buf_allowed, ("unmapped disabled")); 836 837 size = round_page(bp->bio_ma_offset + bp->bio_length); 838 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp)); 839 addr = 0; 840 retried = 0; 841 atomic_add_long(&transient_maps, 1); 842 retry: 843 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) { 844 if (transient_map_retries != 0 && 845 retried >= transient_map_retries) { 846 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s", 847 bp, bp->bio_to->name); 848 atomic_add_int(&transient_map_hard_failures, 1); 849 return (EDEADLK/* XXXKIB */); 850 } else { 851 /* 852 * Naive attempt to quisce the I/O to get more 853 * in-flight requests completed and defragment 854 * the transient_arena. 855 */ 856 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d", 857 bp, bp->bio_to->name, retried); 858 pause("g_d_tra", hz / 10); 859 retried++; 860 atomic_add_int(&transient_map_soft_failures, 1); 861 goto retry; 862 } 863 } 864 atomic_add_int(&inflight_transient_maps, 1); 865 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size)); 866 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset; 867 bp->bio_flags |= BIO_TRANSIENT_MAPPING; 868 bp->bio_flags &= ~BIO_UNMAPPED; 869 return (EJUSTRETURN); 870 } 871 872 void 873 g_io_schedule_down(struct thread *tp __unused) 874 { 875 struct bio *bp; 876 int error; 877 878 for(;;) { 879 g_bioq_lock(&g_bio_run_down); 880 bp = g_bioq_first(&g_bio_run_down); 881 if (bp == NULL) { 882 CTR0(KTR_GEOM, "g_down going to sleep"); 883 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 884 PRIBIO | PDROP, "-", 0); 885 continue; 886 } 887 CTR0(KTR_GEOM, "g_down has work to do"); 888 g_bioq_unlock(&g_bio_run_down); 889 biotrack(bp, __func__); 890 if (pace != 0) { 891 /* 892 * There has been at least one memory allocation 893 * failure since the last I/O completed. Pause 1ms to 894 * give the system a chance to free up memory. We only 895 * do this once because a large number of allocations 896 * can fail in the direct dispatch case and there's no 897 * relationship between the number of these failures and 898 * the length of the outage. If there's still an outage, 899 * we'll pause again and again until it's 900 * resolved. Older versions paused longer and once per 901 * allocation failure. This was OK for a single threaded 902 * g_down, but with direct dispatch would lead to max of 903 * 10 IOPs for minutes at a time when transient memory 904 * issues prevented allocation for a batch of requests 905 * from the upper layers. 906 * 907 * XXX This pacing is really lame. It needs to be solved 908 * by other methods. This is OK only because the worst 909 * case scenario is so rare. In the worst case scenario 910 * all memory is tied up waiting for I/O to complete 911 * which can never happen since we can't allocate bios 912 * for that I/O. 913 */ 914 CTR0(KTR_GEOM, "g_down pacing self"); 915 pause("g_down", min(hz/1000, 1)); 916 pace = 0; 917 } 918 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp, 919 bp->bio_to->name); 920 error = g_io_check(bp); 921 if (error >= 0) { 922 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider " 923 "%s returned %d", bp, bp->bio_to->name, error); 924 g_io_deliver(bp, error); 925 continue; 926 } 927 THREAD_NO_SLEEPING(); 928 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld " 929 "len %ld", bp, bp->bio_to->name, bp->bio_offset, 930 bp->bio_length); 931 bp->bio_to->geom->start(bp); 932 THREAD_SLEEPING_OK(); 933 } 934 } 935 936 void 937 g_io_schedule_up(struct thread *tp __unused) 938 { 939 struct bio *bp; 940 941 for(;;) { 942 g_bioq_lock(&g_bio_run_up); 943 bp = g_bioq_first(&g_bio_run_up); 944 if (bp == NULL) { 945 CTR0(KTR_GEOM, "g_up going to sleep"); 946 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 947 PRIBIO | PDROP, "-", 0); 948 continue; 949 } 950 g_bioq_unlock(&g_bio_run_up); 951 THREAD_NO_SLEEPING(); 952 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off " 953 "%jd len %ld", bp, bp->bio_to->name, 954 bp->bio_offset, bp->bio_length); 955 biodone(bp); 956 THREAD_SLEEPING_OK(); 957 } 958 } 959 960 void * 961 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 962 { 963 struct bio *bp; 964 void *ptr; 965 int errorc; 966 967 KASSERT(length > 0 && length >= cp->provider->sectorsize && 968 length <= MAXPHYS, ("g_read_data(): invalid length %jd", 969 (intmax_t)length)); 970 971 bp = g_alloc_bio(); 972 bp->bio_cmd = BIO_READ; 973 bp->bio_done = NULL; 974 bp->bio_offset = offset; 975 bp->bio_length = length; 976 ptr = g_malloc(length, M_WAITOK); 977 bp->bio_data = ptr; 978 g_io_request(bp, cp); 979 errorc = biowait(bp, "gread"); 980 if (error != NULL) 981 *error = errorc; 982 g_destroy_bio(bp); 983 if (errorc) { 984 g_free(ptr); 985 ptr = NULL; 986 } 987 return (ptr); 988 } 989 990 /* 991 * A read function for use by ffs_sbget when used by GEOM-layer routines. 992 */ 993 int 994 g_use_g_read_data(void *devfd, off_t loc, void **bufp, int size) 995 { 996 struct g_consumer *cp; 997 998 KASSERT(*bufp == NULL, 999 ("g_use_g_read_data: non-NULL *bufp %p\n", *bufp)); 1000 1001 cp = (struct g_consumer *)devfd; 1002 /* 1003 * Take care not to issue an invalid I/O request. The offset of 1004 * the superblock candidate must be multiples of the provider's 1005 * sector size, otherwise an FFS can't exist on the provider 1006 * anyway. 1007 */ 1008 if (loc % cp->provider->sectorsize != 0) 1009 return (ENOENT); 1010 *bufp = g_read_data(cp, loc, size, NULL); 1011 if (*bufp == NULL) 1012 return (ENOENT); 1013 return (0); 1014 } 1015 1016 int 1017 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 1018 { 1019 struct bio *bp; 1020 int error; 1021 1022 KASSERT(length > 0 && length >= cp->provider->sectorsize && 1023 length <= MAXPHYS, ("g_write_data(): invalid length %jd", 1024 (intmax_t)length)); 1025 1026 bp = g_alloc_bio(); 1027 bp->bio_cmd = BIO_WRITE; 1028 bp->bio_done = NULL; 1029 bp->bio_offset = offset; 1030 bp->bio_length = length; 1031 bp->bio_data = ptr; 1032 g_io_request(bp, cp); 1033 error = biowait(bp, "gwrite"); 1034 g_destroy_bio(bp); 1035 return (error); 1036 } 1037 1038 /* 1039 * A write function for use by ffs_sbput when used by GEOM-layer routines. 1040 */ 1041 int 1042 g_use_g_write_data(void *devfd, off_t loc, void *buf, int size) 1043 { 1044 1045 return (g_write_data((struct g_consumer *)devfd, loc, buf, size)); 1046 } 1047 1048 int 1049 g_delete_data(struct g_consumer *cp, off_t offset, off_t length) 1050 { 1051 struct bio *bp; 1052 int error; 1053 1054 KASSERT(length > 0 && length >= cp->provider->sectorsize, 1055 ("g_delete_data(): invalid length %jd", (intmax_t)length)); 1056 1057 bp = g_alloc_bio(); 1058 bp->bio_cmd = BIO_DELETE; 1059 bp->bio_done = NULL; 1060 bp->bio_offset = offset; 1061 bp->bio_length = length; 1062 bp->bio_data = NULL; 1063 g_io_request(bp, cp); 1064 error = biowait(bp, "gdelete"); 1065 g_destroy_bio(bp); 1066 return (error); 1067 } 1068 1069 void 1070 g_print_bio(const char *prefix, const struct bio *bp, const char *fmtsuffix, 1071 ...) 1072 { 1073 #ifndef PRINTF_BUFR_SIZE 1074 #define PRINTF_BUFR_SIZE 64 1075 #endif 1076 char bufr[PRINTF_BUFR_SIZE]; 1077 struct sbuf sb, *sbp __unused; 1078 va_list ap; 1079 1080 sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN); 1081 KASSERT(sbp != NULL, ("sbuf_new misused?")); 1082 1083 sbuf_set_drain(&sb, sbuf_printf_drain, NULL); 1084 1085 sbuf_cat(&sb, prefix); 1086 g_format_bio(&sb, bp); 1087 1088 va_start(ap, fmtsuffix); 1089 sbuf_vprintf(&sb, fmtsuffix, ap); 1090 va_end(ap); 1091 1092 sbuf_nl_terminate(&sb); 1093 1094 sbuf_finish(&sb); 1095 sbuf_delete(&sb); 1096 } 1097 1098 void 1099 g_format_bio(struct sbuf *sb, const struct bio *bp) 1100 { 1101 const char *pname, *cmd = NULL; 1102 1103 if (bp->bio_to != NULL) 1104 pname = bp->bio_to->name; 1105 else 1106 pname = "[unknown]"; 1107 1108 switch (bp->bio_cmd) { 1109 case BIO_GETATTR: 1110 cmd = "GETATTR"; 1111 sbuf_printf(sb, "%s[%s(attr=%s)]", pname, cmd, 1112 bp->bio_attribute); 1113 return; 1114 case BIO_FLUSH: 1115 cmd = "FLUSH"; 1116 sbuf_printf(sb, "%s[%s]", pname, cmd); 1117 return; 1118 case BIO_ZONE: { 1119 char *subcmd = NULL; 1120 cmd = "ZONE"; 1121 switch (bp->bio_zone.zone_cmd) { 1122 case DISK_ZONE_OPEN: 1123 subcmd = "OPEN"; 1124 break; 1125 case DISK_ZONE_CLOSE: 1126 subcmd = "CLOSE"; 1127 break; 1128 case DISK_ZONE_FINISH: 1129 subcmd = "FINISH"; 1130 break; 1131 case DISK_ZONE_RWP: 1132 subcmd = "RWP"; 1133 break; 1134 case DISK_ZONE_REPORT_ZONES: 1135 subcmd = "REPORT ZONES"; 1136 break; 1137 case DISK_ZONE_GET_PARAMS: 1138 subcmd = "GET PARAMS"; 1139 break; 1140 default: 1141 subcmd = "UNKNOWN"; 1142 break; 1143 } 1144 sbuf_printf(sb, "%s[%s,%s]", pname, cmd, subcmd); 1145 return; 1146 } 1147 case BIO_READ: 1148 cmd = "READ"; 1149 break; 1150 case BIO_WRITE: 1151 cmd = "WRITE"; 1152 break; 1153 case BIO_DELETE: 1154 cmd = "DELETE"; 1155 break; 1156 default: 1157 cmd = "UNKNOWN"; 1158 sbuf_printf(sb, "%s[%s()]", pname, cmd); 1159 return; 1160 } 1161 sbuf_printf(sb, "%s[%s(offset=%jd, length=%jd)]", pname, cmd, 1162 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 1163 } 1164