1 /*- 2 * Copyright (c) 2002 Poul-Henning Kamp 3 * Copyright (c) 2002 Networks Associates Technology, Inc. 4 * Copyright (c) 2013 The FreeBSD Foundation 5 * All rights reserved. 6 * 7 * This software was developed for the FreeBSD Project by Poul-Henning Kamp 8 * and NAI Labs, the Security Research Division of Network Associates, Inc. 9 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 10 * DARPA CHATS research program. 11 * 12 * Portions of this software were developed by Konstantin Belousov 13 * under sponsorship from the FreeBSD Foundation. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. The names of the authors may not be used to endorse or promote 24 * products derived from this software without specific prior written 25 * permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 */ 39 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/malloc.h> 47 #include <sys/bio.h> 48 #include <sys/ktr.h> 49 #include <sys/proc.h> 50 #include <sys/stack.h> 51 #include <sys/sysctl.h> 52 #include <sys/vmem.h> 53 54 #include <sys/errno.h> 55 #include <geom/geom.h> 56 #include <geom/geom_int.h> 57 #include <sys/devicestat.h> 58 59 #include <vm/uma.h> 60 #include <vm/vm.h> 61 #include <vm/vm_param.h> 62 #include <vm/vm_kern.h> 63 #include <vm/vm_page.h> 64 #include <vm/vm_object.h> 65 #include <vm/vm_extern.h> 66 #include <vm/vm_map.h> 67 68 static int g_io_transient_map_bio(struct bio *bp); 69 70 static struct g_bioq g_bio_run_down; 71 static struct g_bioq g_bio_run_up; 72 73 /* 74 * Pace is a hint that we've had some trouble recently allocating 75 * bios, so we should back off trying to send I/O down the stack 76 * a bit to let the problem resolve. When pacing, we also turn 77 * off direct dispatch to also reduce memory pressure from I/Os 78 * there, at the expxense of some added latency while the memory 79 * pressures exist. See g_io_schedule_down() for more details 80 * and limitations. 81 */ 82 static volatile u_int pace; 83 84 static uma_zone_t biozone; 85 86 /* 87 * The head of the list of classifiers used in g_io_request. 88 * Use g_register_classifier() and g_unregister_classifier() 89 * to add/remove entries to the list. 90 * Classifiers are invoked in registration order. 91 */ 92 static TAILQ_HEAD(g_classifier_tailq, g_classifier_hook) 93 g_classifier_tailq = TAILQ_HEAD_INITIALIZER(g_classifier_tailq); 94 95 #include <machine/atomic.h> 96 97 static void 98 g_bioq_lock(struct g_bioq *bq) 99 { 100 101 mtx_lock(&bq->bio_queue_lock); 102 } 103 104 static void 105 g_bioq_unlock(struct g_bioq *bq) 106 { 107 108 mtx_unlock(&bq->bio_queue_lock); 109 } 110 111 #if 0 112 static void 113 g_bioq_destroy(struct g_bioq *bq) 114 { 115 116 mtx_destroy(&bq->bio_queue_lock); 117 } 118 #endif 119 120 static void 121 g_bioq_init(struct g_bioq *bq) 122 { 123 124 TAILQ_INIT(&bq->bio_queue); 125 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 126 } 127 128 static struct bio * 129 g_bioq_first(struct g_bioq *bq) 130 { 131 struct bio *bp; 132 133 bp = TAILQ_FIRST(&bq->bio_queue); 134 if (bp != NULL) { 135 KASSERT((bp->bio_flags & BIO_ONQUEUE), 136 ("Bio not on queue bp=%p target %p", bp, bq)); 137 bp->bio_flags &= ~BIO_ONQUEUE; 138 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 139 bq->bio_queue_length--; 140 } 141 return (bp); 142 } 143 144 struct bio * 145 g_new_bio(void) 146 { 147 struct bio *bp; 148 149 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 150 #ifdef KTR 151 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 152 struct stack st; 153 154 CTR1(KTR_GEOM, "g_new_bio(): %p", bp); 155 stack_save(&st); 156 CTRSTACK(KTR_GEOM, &st, 3, 0); 157 } 158 #endif 159 return (bp); 160 } 161 162 struct bio * 163 g_alloc_bio(void) 164 { 165 struct bio *bp; 166 167 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); 168 #ifdef KTR 169 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 170 struct stack st; 171 172 CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp); 173 stack_save(&st); 174 CTRSTACK(KTR_GEOM, &st, 3, 0); 175 } 176 #endif 177 return (bp); 178 } 179 180 void 181 g_destroy_bio(struct bio *bp) 182 { 183 #ifdef KTR 184 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 185 struct stack st; 186 187 CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp); 188 stack_save(&st); 189 CTRSTACK(KTR_GEOM, &st, 3, 0); 190 } 191 #endif 192 uma_zfree(biozone, bp); 193 } 194 195 struct bio * 196 g_clone_bio(struct bio *bp) 197 { 198 struct bio *bp2; 199 200 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 201 if (bp2 != NULL) { 202 bp2->bio_parent = bp; 203 bp2->bio_cmd = bp->bio_cmd; 204 /* 205 * BIO_ORDERED flag may be used by disk drivers to enforce 206 * ordering restrictions, so this flag needs to be cloned. 207 * BIO_UNMAPPED and BIO_VLIST should be inherited, to properly 208 * indicate which way the buffer is passed. 209 * Other bio flags are not suitable for cloning. 210 */ 211 bp2->bio_flags = bp->bio_flags & 212 (BIO_ORDERED | BIO_UNMAPPED | BIO_VLIST); 213 bp2->bio_length = bp->bio_length; 214 bp2->bio_offset = bp->bio_offset; 215 bp2->bio_data = bp->bio_data; 216 bp2->bio_ma = bp->bio_ma; 217 bp2->bio_ma_n = bp->bio_ma_n; 218 bp2->bio_ma_offset = bp->bio_ma_offset; 219 bp2->bio_attribute = bp->bio_attribute; 220 if (bp->bio_cmd == BIO_ZONE) 221 bcopy(&bp->bio_zone, &bp2->bio_zone, 222 sizeof(bp->bio_zone)); 223 /* Inherit classification info from the parent */ 224 bp2->bio_classifier1 = bp->bio_classifier1; 225 bp2->bio_classifier2 = bp->bio_classifier2; 226 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING) 227 bp2->bio_track_bp = bp->bio_track_bp; 228 #endif 229 bp->bio_children++; 230 } 231 #ifdef KTR 232 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 233 struct stack st; 234 235 CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2); 236 stack_save(&st); 237 CTRSTACK(KTR_GEOM, &st, 3, 0); 238 } 239 #endif 240 return(bp2); 241 } 242 243 struct bio * 244 g_duplicate_bio(struct bio *bp) 245 { 246 struct bio *bp2; 247 248 bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO); 249 bp2->bio_flags = bp->bio_flags & (BIO_UNMAPPED | BIO_VLIST); 250 bp2->bio_parent = bp; 251 bp2->bio_cmd = bp->bio_cmd; 252 bp2->bio_length = bp->bio_length; 253 bp2->bio_offset = bp->bio_offset; 254 bp2->bio_data = bp->bio_data; 255 bp2->bio_ma = bp->bio_ma; 256 bp2->bio_ma_n = bp->bio_ma_n; 257 bp2->bio_ma_offset = bp->bio_ma_offset; 258 bp2->bio_attribute = bp->bio_attribute; 259 bp->bio_children++; 260 #ifdef KTR 261 if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) { 262 struct stack st; 263 264 CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2); 265 stack_save(&st); 266 CTRSTACK(KTR_GEOM, &st, 3, 0); 267 } 268 #endif 269 return(bp2); 270 } 271 272 void 273 g_reset_bio(struct bio *bp) 274 { 275 276 bzero(bp, sizeof(*bp)); 277 } 278 279 void 280 g_io_init() 281 { 282 283 g_bioq_init(&g_bio_run_down); 284 g_bioq_init(&g_bio_run_up); 285 biozone = uma_zcreate("g_bio", sizeof (struct bio), 286 NULL, NULL, 287 NULL, NULL, 288 0, 0); 289 } 290 291 int 292 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 293 { 294 struct bio *bp; 295 int error; 296 297 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 298 bp = g_alloc_bio(); 299 bp->bio_cmd = BIO_GETATTR; 300 bp->bio_done = NULL; 301 bp->bio_attribute = attr; 302 bp->bio_length = *len; 303 bp->bio_data = ptr; 304 g_io_request(bp, cp); 305 error = biowait(bp, "ggetattr"); 306 *len = bp->bio_completed; 307 g_destroy_bio(bp); 308 return (error); 309 } 310 311 int 312 g_io_zonecmd(struct disk_zone_args *zone_args, struct g_consumer *cp) 313 { 314 struct bio *bp; 315 int error; 316 317 g_trace(G_T_BIO, "bio_zone(%d)", zone_args->zone_cmd); 318 bp = g_alloc_bio(); 319 bp->bio_cmd = BIO_ZONE; 320 bp->bio_done = NULL; 321 /* 322 * XXX KDM need to handle report zone data. 323 */ 324 bcopy(zone_args, &bp->bio_zone, sizeof(*zone_args)); 325 if (zone_args->zone_cmd == DISK_ZONE_REPORT_ZONES) 326 bp->bio_length = 327 zone_args->zone_params.report.entries_allocated * 328 sizeof(struct disk_zone_rep_entry); 329 else 330 bp->bio_length = 0; 331 332 g_io_request(bp, cp); 333 error = biowait(bp, "gzone"); 334 bcopy(&bp->bio_zone, zone_args, sizeof(*zone_args)); 335 g_destroy_bio(bp); 336 return (error); 337 } 338 339 int 340 g_io_flush(struct g_consumer *cp) 341 { 342 struct bio *bp; 343 int error; 344 345 g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name); 346 bp = g_alloc_bio(); 347 bp->bio_cmd = BIO_FLUSH; 348 bp->bio_flags |= BIO_ORDERED; 349 bp->bio_done = NULL; 350 bp->bio_attribute = NULL; 351 bp->bio_offset = cp->provider->mediasize; 352 bp->bio_length = 0; 353 bp->bio_data = NULL; 354 g_io_request(bp, cp); 355 error = biowait(bp, "gflush"); 356 g_destroy_bio(bp); 357 return (error); 358 } 359 360 static int 361 g_io_check(struct bio *bp) 362 { 363 struct g_consumer *cp; 364 struct g_provider *pp; 365 off_t excess; 366 int error; 367 368 biotrack(bp, __func__); 369 370 cp = bp->bio_from; 371 pp = bp->bio_to; 372 373 /* Fail if access counters dont allow the operation */ 374 switch(bp->bio_cmd) { 375 case BIO_READ: 376 case BIO_GETATTR: 377 if (cp->acr == 0) 378 return (EPERM); 379 break; 380 case BIO_WRITE: 381 case BIO_DELETE: 382 case BIO_FLUSH: 383 if (cp->acw == 0) 384 return (EPERM); 385 break; 386 case BIO_ZONE: 387 if ((bp->bio_zone.zone_cmd == DISK_ZONE_REPORT_ZONES) || 388 (bp->bio_zone.zone_cmd == DISK_ZONE_GET_PARAMS)) { 389 if (cp->acr == 0) 390 return (EPERM); 391 } else if (cp->acw == 0) 392 return (EPERM); 393 break; 394 default: 395 return (EPERM); 396 } 397 /* if provider is marked for error, don't disturb. */ 398 if (pp->error) 399 return (pp->error); 400 if (cp->flags & G_CF_ORPHAN) 401 return (ENXIO); 402 403 switch(bp->bio_cmd) { 404 case BIO_READ: 405 case BIO_WRITE: 406 case BIO_DELETE: 407 /* Zero sectorsize or mediasize is probably a lack of media. */ 408 if (pp->sectorsize == 0 || pp->mediasize == 0) 409 return (ENXIO); 410 /* Reject I/O not on sector boundary */ 411 if (bp->bio_offset % pp->sectorsize) 412 return (EINVAL); 413 /* Reject I/O not integral sector long */ 414 if (bp->bio_length % pp->sectorsize) 415 return (EINVAL); 416 /* Reject requests before or past the end of media. */ 417 if (bp->bio_offset < 0) 418 return (EIO); 419 if (bp->bio_offset > pp->mediasize) 420 return (EIO); 421 422 /* Truncate requests to the end of providers media. */ 423 excess = bp->bio_offset + bp->bio_length; 424 if (excess > bp->bio_to->mediasize) { 425 KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 || 426 round_page(bp->bio_ma_offset + 427 bp->bio_length) / PAGE_SIZE == bp->bio_ma_n, 428 ("excess bio %p too short", bp)); 429 excess -= bp->bio_to->mediasize; 430 bp->bio_length -= excess; 431 if ((bp->bio_flags & BIO_UNMAPPED) != 0) { 432 bp->bio_ma_n = round_page(bp->bio_ma_offset + 433 bp->bio_length) / PAGE_SIZE; 434 } 435 if (excess > 0) 436 CTR3(KTR_GEOM, "g_down truncated bio " 437 "%p provider %s by %d", bp, 438 bp->bio_to->name, excess); 439 } 440 441 /* Deliver zero length transfers right here. */ 442 if (bp->bio_length == 0) { 443 CTR2(KTR_GEOM, "g_down terminated 0-length " 444 "bp %p provider %s", bp, bp->bio_to->name); 445 return (0); 446 } 447 448 if ((bp->bio_flags & BIO_UNMAPPED) != 0 && 449 (bp->bio_to->flags & G_PF_ACCEPT_UNMAPPED) == 0 && 450 (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE)) { 451 if ((error = g_io_transient_map_bio(bp)) >= 0) 452 return (error); 453 } 454 break; 455 default: 456 break; 457 } 458 return (EJUSTRETURN); 459 } 460 461 /* 462 * bio classification support. 463 * 464 * g_register_classifier() and g_unregister_classifier() 465 * are used to add/remove a classifier from the list. 466 * The list is protected using the g_bio_run_down lock, 467 * because the classifiers are called in this path. 468 * 469 * g_io_request() passes bio's that are not already classified 470 * (i.e. those with bio_classifier1 == NULL) to g_run_classifiers(). 471 * Classifiers can store their result in the two fields 472 * bio_classifier1 and bio_classifier2. 473 * A classifier that updates one of the fields should 474 * return a non-zero value. 475 * If no classifier updates the field, g_run_classifiers() sets 476 * bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls. 477 */ 478 479 int 480 g_register_classifier(struct g_classifier_hook *hook) 481 { 482 483 g_bioq_lock(&g_bio_run_down); 484 TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link); 485 g_bioq_unlock(&g_bio_run_down); 486 487 return (0); 488 } 489 490 void 491 g_unregister_classifier(struct g_classifier_hook *hook) 492 { 493 struct g_classifier_hook *entry; 494 495 g_bioq_lock(&g_bio_run_down); 496 TAILQ_FOREACH(entry, &g_classifier_tailq, link) { 497 if (entry == hook) { 498 TAILQ_REMOVE(&g_classifier_tailq, hook, link); 499 break; 500 } 501 } 502 g_bioq_unlock(&g_bio_run_down); 503 } 504 505 static void 506 g_run_classifiers(struct bio *bp) 507 { 508 struct g_classifier_hook *hook; 509 int classified = 0; 510 511 biotrack(bp, __func__); 512 513 TAILQ_FOREACH(hook, &g_classifier_tailq, link) 514 classified |= hook->func(hook->arg, bp); 515 516 if (!classified) 517 bp->bio_classifier1 = BIO_NOTCLASSIFIED; 518 } 519 520 void 521 g_io_request(struct bio *bp, struct g_consumer *cp) 522 { 523 struct g_provider *pp; 524 struct mtx *mtxp; 525 int direct, error, first; 526 uint8_t cmd; 527 528 biotrack(bp, __func__); 529 530 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 531 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 532 pp = cp->provider; 533 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 534 #ifdef DIAGNOSTIC 535 KASSERT(bp->bio_driver1 == NULL, 536 ("bio_driver1 used by the consumer (geom %s)", cp->geom->name)); 537 KASSERT(bp->bio_driver2 == NULL, 538 ("bio_driver2 used by the consumer (geom %s)", cp->geom->name)); 539 KASSERT(bp->bio_pflags == 0, 540 ("bio_pflags used by the consumer (geom %s)", cp->geom->name)); 541 /* 542 * Remember consumer's private fields, so we can detect if they were 543 * modified by the provider. 544 */ 545 bp->_bio_caller1 = bp->bio_caller1; 546 bp->_bio_caller2 = bp->bio_caller2; 547 bp->_bio_cflags = bp->bio_cflags; 548 #endif 549 550 cmd = bp->bio_cmd; 551 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_GETATTR) { 552 KASSERT(bp->bio_data != NULL, 553 ("NULL bp->data in g_io_request(cmd=%hu)", bp->bio_cmd)); 554 } 555 if (cmd == BIO_DELETE || cmd == BIO_FLUSH) { 556 KASSERT(bp->bio_data == NULL, 557 ("non-NULL bp->data in g_io_request(cmd=%hu)", 558 bp->bio_cmd)); 559 } 560 if (cmd == BIO_READ || cmd == BIO_WRITE || cmd == BIO_DELETE) { 561 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, 562 ("wrong offset %jd for sectorsize %u", 563 bp->bio_offset, cp->provider->sectorsize)); 564 KASSERT(bp->bio_length % cp->provider->sectorsize == 0, 565 ("wrong length %jd for sectorsize %u", 566 bp->bio_length, cp->provider->sectorsize)); 567 } 568 569 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 570 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 571 572 bp->bio_from = cp; 573 bp->bio_to = pp; 574 bp->bio_error = 0; 575 bp->bio_completed = 0; 576 577 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 578 ("Bio already on queue bp=%p", bp)); 579 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 580 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 581 binuptime(&bp->bio_t0); 582 else 583 getbinuptime(&bp->bio_t0); 584 585 #ifdef GET_STACK_USAGE 586 direct = (cp->flags & G_CF_DIRECT_SEND) != 0 && 587 (pp->flags & G_PF_DIRECT_RECEIVE) != 0 && 588 !g_is_geom_thread(curthread) && 589 ((pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 || 590 (bp->bio_flags & BIO_UNMAPPED) == 0 || THREAD_CAN_SLEEP()) && 591 pace == 0; 592 if (direct) { 593 /* Block direct execution if less then half of stack left. */ 594 size_t st, su; 595 GET_STACK_USAGE(st, su); 596 if (su * 2 > st) 597 direct = 0; 598 } 599 #else 600 direct = 0; 601 #endif 602 603 if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1) { 604 g_bioq_lock(&g_bio_run_down); 605 g_run_classifiers(bp); 606 g_bioq_unlock(&g_bio_run_down); 607 } 608 609 /* 610 * The statistics collection is lockless, as such, but we 611 * can not update one instance of the statistics from more 612 * than one thread at a time, so grab the lock first. 613 */ 614 mtxp = mtx_pool_find(mtxpool_sleep, pp); 615 mtx_lock(mtxp); 616 if (g_collectstats & G_STATS_PROVIDERS) 617 devstat_start_transaction(pp->stat, &bp->bio_t0); 618 if (g_collectstats & G_STATS_CONSUMERS) 619 devstat_start_transaction(cp->stat, &bp->bio_t0); 620 pp->nstart++; 621 cp->nstart++; 622 mtx_unlock(mtxp); 623 624 if (direct) { 625 error = g_io_check(bp); 626 if (error >= 0) { 627 CTR3(KTR_GEOM, "g_io_request g_io_check on bp %p " 628 "provider %s returned %d", bp, bp->bio_to->name, 629 error); 630 g_io_deliver(bp, error); 631 return; 632 } 633 bp->bio_to->geom->start(bp); 634 } else { 635 g_bioq_lock(&g_bio_run_down); 636 first = TAILQ_EMPTY(&g_bio_run_down.bio_queue); 637 TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue); 638 bp->bio_flags |= BIO_ONQUEUE; 639 g_bio_run_down.bio_queue_length++; 640 g_bioq_unlock(&g_bio_run_down); 641 /* Pass it on down. */ 642 if (first) 643 wakeup(&g_wait_down); 644 } 645 } 646 647 void 648 g_io_deliver(struct bio *bp, int error) 649 { 650 struct bintime now; 651 struct g_consumer *cp; 652 struct g_provider *pp; 653 struct mtx *mtxp; 654 int direct, first; 655 656 biotrack(bp, __func__); 657 658 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 659 pp = bp->bio_to; 660 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 661 cp = bp->bio_from; 662 if (cp == NULL) { 663 bp->bio_error = error; 664 bp->bio_done(bp); 665 return; 666 } 667 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 668 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 669 #ifdef DIAGNOSTIC 670 /* 671 * Some classes - GJournal in particular - can modify bio's 672 * private fields while the bio is in transit; G_GEOM_VOLATILE_BIO 673 * flag means it's an expected behaviour for that particular geom. 674 */ 675 if ((cp->geom->flags & G_GEOM_VOLATILE_BIO) == 0) { 676 KASSERT(bp->bio_caller1 == bp->_bio_caller1, 677 ("bio_caller1 used by the provider %s", pp->name)); 678 KASSERT(bp->bio_caller2 == bp->_bio_caller2, 679 ("bio_caller2 used by the provider %s", pp->name)); 680 KASSERT(bp->bio_cflags == bp->_bio_cflags, 681 ("bio_cflags used by the provider %s", pp->name)); 682 } 683 #endif 684 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 685 KASSERT(bp->bio_completed <= bp->bio_length, 686 ("bio_completed can't be greater than bio_length")); 687 688 g_trace(G_T_BIO, 689 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 690 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 691 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 692 693 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 694 ("Bio already on queue bp=%p", bp)); 695 696 /* 697 * XXX: next two doesn't belong here 698 */ 699 bp->bio_bcount = bp->bio_length; 700 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 701 702 #ifdef GET_STACK_USAGE 703 direct = (pp->flags & G_PF_DIRECT_SEND) && 704 (cp->flags & G_CF_DIRECT_RECEIVE) && 705 !g_is_geom_thread(curthread); 706 if (direct) { 707 /* Block direct execution if less then half of stack left. */ 708 size_t st, su; 709 GET_STACK_USAGE(st, su); 710 if (su * 2 > st) 711 direct = 0; 712 } 713 #else 714 direct = 0; 715 #endif 716 717 /* 718 * The statistics collection is lockless, as such, but we 719 * can not update one instance of the statistics from more 720 * than one thread at a time, so grab the lock first. 721 */ 722 if ((g_collectstats & G_STATS_CONSUMERS) != 0 || 723 ((g_collectstats & G_STATS_PROVIDERS) != 0 && pp->stat != NULL)) 724 binuptime(&now); 725 mtxp = mtx_pool_find(mtxpool_sleep, cp); 726 mtx_lock(mtxp); 727 if (g_collectstats & G_STATS_PROVIDERS) 728 devstat_end_transaction_bio_bt(pp->stat, bp, &now); 729 if (g_collectstats & G_STATS_CONSUMERS) 730 devstat_end_transaction_bio_bt(cp->stat, bp, &now); 731 cp->nend++; 732 pp->nend++; 733 mtx_unlock(mtxp); 734 735 if (error != ENOMEM) { 736 bp->bio_error = error; 737 if (direct) { 738 biodone(bp); 739 } else { 740 g_bioq_lock(&g_bio_run_up); 741 first = TAILQ_EMPTY(&g_bio_run_up.bio_queue); 742 TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue); 743 bp->bio_flags |= BIO_ONQUEUE; 744 g_bio_run_up.bio_queue_length++; 745 g_bioq_unlock(&g_bio_run_up); 746 if (first) 747 wakeup(&g_wait_up); 748 } 749 return; 750 } 751 752 if (bootverbose) 753 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 754 bp->bio_children = 0; 755 bp->bio_inbed = 0; 756 bp->bio_driver1 = NULL; 757 bp->bio_driver2 = NULL; 758 bp->bio_pflags = 0; 759 g_io_request(bp, cp); 760 pace = 1; 761 return; 762 } 763 764 SYSCTL_DECL(_kern_geom); 765 766 static long transient_maps; 767 SYSCTL_LONG(_kern_geom, OID_AUTO, transient_maps, CTLFLAG_RD, 768 &transient_maps, 0, 769 "Total count of the transient mapping requests"); 770 u_int transient_map_retries = 10; 771 SYSCTL_UINT(_kern_geom, OID_AUTO, transient_map_retries, CTLFLAG_RW, 772 &transient_map_retries, 0, 773 "Max count of retries used before giving up on creating transient map"); 774 int transient_map_hard_failures; 775 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_hard_failures, CTLFLAG_RD, 776 &transient_map_hard_failures, 0, 777 "Failures to establish the transient mapping due to retry attempts " 778 "exhausted"); 779 int transient_map_soft_failures; 780 SYSCTL_INT(_kern_geom, OID_AUTO, transient_map_soft_failures, CTLFLAG_RD, 781 &transient_map_soft_failures, 0, 782 "Count of retried failures to establish the transient mapping"); 783 int inflight_transient_maps; 784 SYSCTL_INT(_kern_geom, OID_AUTO, inflight_transient_maps, CTLFLAG_RD, 785 &inflight_transient_maps, 0, 786 "Current count of the active transient maps"); 787 788 static int 789 g_io_transient_map_bio(struct bio *bp) 790 { 791 vm_offset_t addr; 792 long size; 793 u_int retried; 794 795 KASSERT(unmapped_buf_allowed, ("unmapped disabled")); 796 797 size = round_page(bp->bio_ma_offset + bp->bio_length); 798 KASSERT(size / PAGE_SIZE == bp->bio_ma_n, ("Bio too short %p", bp)); 799 addr = 0; 800 retried = 0; 801 atomic_add_long(&transient_maps, 1); 802 retry: 803 if (vmem_alloc(transient_arena, size, M_BESTFIT | M_NOWAIT, &addr)) { 804 if (transient_map_retries != 0 && 805 retried >= transient_map_retries) { 806 CTR2(KTR_GEOM, "g_down cannot map bp %p provider %s", 807 bp, bp->bio_to->name); 808 atomic_add_int(&transient_map_hard_failures, 1); 809 return (EDEADLK/* XXXKIB */); 810 } else { 811 /* 812 * Naive attempt to quisce the I/O to get more 813 * in-flight requests completed and defragment 814 * the transient_arena. 815 */ 816 CTR3(KTR_GEOM, "g_down retrymap bp %p provider %s r %d", 817 bp, bp->bio_to->name, retried); 818 pause("g_d_tra", hz / 10); 819 retried++; 820 atomic_add_int(&transient_map_soft_failures, 1); 821 goto retry; 822 } 823 } 824 atomic_add_int(&inflight_transient_maps, 1); 825 pmap_qenter((vm_offset_t)addr, bp->bio_ma, OFF_TO_IDX(size)); 826 bp->bio_data = (caddr_t)addr + bp->bio_ma_offset; 827 bp->bio_flags |= BIO_TRANSIENT_MAPPING; 828 bp->bio_flags &= ~BIO_UNMAPPED; 829 return (EJUSTRETURN); 830 } 831 832 void 833 g_io_schedule_down(struct thread *tp __unused) 834 { 835 struct bio *bp; 836 int error; 837 838 for(;;) { 839 g_bioq_lock(&g_bio_run_down); 840 bp = g_bioq_first(&g_bio_run_down); 841 if (bp == NULL) { 842 CTR0(KTR_GEOM, "g_down going to sleep"); 843 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 844 PRIBIO | PDROP, "-", 0); 845 continue; 846 } 847 CTR0(KTR_GEOM, "g_down has work to do"); 848 g_bioq_unlock(&g_bio_run_down); 849 biotrack(bp, __func__); 850 if (pace != 0) { 851 /* 852 * There has been at least one memory allocation 853 * failure since the last I/O completed. Pause 1ms to 854 * give the system a chance to free up memory. We only 855 * do this once because a large number of allocations 856 * can fail in the direct dispatch case and there's no 857 * relationship between the number of these failures and 858 * the length of the outage. If there's still an outage, 859 * we'll pause again and again until it's 860 * resolved. Older versions paused longer and once per 861 * allocation failure. This was OK for a single threaded 862 * g_down, but with direct dispatch would lead to max of 863 * 10 IOPs for minutes at a time when transient memory 864 * issues prevented allocation for a batch of requests 865 * from the upper layers. 866 * 867 * XXX This pacing is really lame. It needs to be solved 868 * by other methods. This is OK only because the worst 869 * case scenario is so rare. In the worst case scenario 870 * all memory is tied up waiting for I/O to complete 871 * which can never happen since we can't allocate bios 872 * for that I/O. 873 */ 874 CTR0(KTR_GEOM, "g_down pacing self"); 875 pause("g_down", min(hz/1000, 1)); 876 pace = 0; 877 } 878 CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp, 879 bp->bio_to->name); 880 error = g_io_check(bp); 881 if (error >= 0) { 882 CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider " 883 "%s returned %d", bp, bp->bio_to->name, error); 884 g_io_deliver(bp, error); 885 continue; 886 } 887 THREAD_NO_SLEEPING(); 888 CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld " 889 "len %ld", bp, bp->bio_to->name, bp->bio_offset, 890 bp->bio_length); 891 bp->bio_to->geom->start(bp); 892 THREAD_SLEEPING_OK(); 893 } 894 } 895 896 void 897 g_io_schedule_up(struct thread *tp __unused) 898 { 899 struct bio *bp; 900 901 for(;;) { 902 g_bioq_lock(&g_bio_run_up); 903 bp = g_bioq_first(&g_bio_run_up); 904 if (bp == NULL) { 905 CTR0(KTR_GEOM, "g_up going to sleep"); 906 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 907 PRIBIO | PDROP, "-", 0); 908 continue; 909 } 910 g_bioq_unlock(&g_bio_run_up); 911 THREAD_NO_SLEEPING(); 912 CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off " 913 "%jd len %ld", bp, bp->bio_to->name, 914 bp->bio_offset, bp->bio_length); 915 biodone(bp); 916 THREAD_SLEEPING_OK(); 917 } 918 } 919 920 void * 921 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 922 { 923 struct bio *bp; 924 void *ptr; 925 int errorc; 926 927 KASSERT(length > 0 && length >= cp->provider->sectorsize && 928 length <= MAXPHYS, ("g_read_data(): invalid length %jd", 929 (intmax_t)length)); 930 931 bp = g_alloc_bio(); 932 bp->bio_cmd = BIO_READ; 933 bp->bio_done = NULL; 934 bp->bio_offset = offset; 935 bp->bio_length = length; 936 ptr = g_malloc(length, M_WAITOK); 937 bp->bio_data = ptr; 938 g_io_request(bp, cp); 939 errorc = biowait(bp, "gread"); 940 if (error != NULL) 941 *error = errorc; 942 g_destroy_bio(bp); 943 if (errorc) { 944 g_free(ptr); 945 ptr = NULL; 946 } 947 return (ptr); 948 } 949 950 int 951 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 952 { 953 struct bio *bp; 954 int error; 955 956 KASSERT(length > 0 && length >= cp->provider->sectorsize && 957 length <= MAXPHYS, ("g_write_data(): invalid length %jd", 958 (intmax_t)length)); 959 960 bp = g_alloc_bio(); 961 bp->bio_cmd = BIO_WRITE; 962 bp->bio_done = NULL; 963 bp->bio_offset = offset; 964 bp->bio_length = length; 965 bp->bio_data = ptr; 966 g_io_request(bp, cp); 967 error = biowait(bp, "gwrite"); 968 g_destroy_bio(bp); 969 return (error); 970 } 971 972 int 973 g_delete_data(struct g_consumer *cp, off_t offset, off_t length) 974 { 975 struct bio *bp; 976 int error; 977 978 KASSERT(length > 0 && length >= cp->provider->sectorsize, 979 ("g_delete_data(): invalid length %jd", (intmax_t)length)); 980 981 bp = g_alloc_bio(); 982 bp->bio_cmd = BIO_DELETE; 983 bp->bio_done = NULL; 984 bp->bio_offset = offset; 985 bp->bio_length = length; 986 bp->bio_data = NULL; 987 g_io_request(bp, cp); 988 error = biowait(bp, "gdelete"); 989 g_destroy_bio(bp); 990 return (error); 991 } 992 993 void 994 g_print_bio(struct bio *bp) 995 { 996 const char *pname, *cmd = NULL; 997 998 if (bp->bio_to != NULL) 999 pname = bp->bio_to->name; 1000 else 1001 pname = "[unknown]"; 1002 1003 switch (bp->bio_cmd) { 1004 case BIO_GETATTR: 1005 cmd = "GETATTR"; 1006 printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute); 1007 return; 1008 case BIO_FLUSH: 1009 cmd = "FLUSH"; 1010 printf("%s[%s]", pname, cmd); 1011 return; 1012 case BIO_ZONE: { 1013 char *subcmd = NULL; 1014 cmd = "ZONE"; 1015 switch (bp->bio_zone.zone_cmd) { 1016 case DISK_ZONE_OPEN: 1017 subcmd = "OPEN"; 1018 break; 1019 case DISK_ZONE_CLOSE: 1020 subcmd = "CLOSE"; 1021 break; 1022 case DISK_ZONE_FINISH: 1023 subcmd = "FINISH"; 1024 break; 1025 case DISK_ZONE_RWP: 1026 subcmd = "RWP"; 1027 break; 1028 case DISK_ZONE_REPORT_ZONES: 1029 subcmd = "REPORT ZONES"; 1030 break; 1031 case DISK_ZONE_GET_PARAMS: 1032 subcmd = "GET PARAMS"; 1033 break; 1034 default: 1035 subcmd = "UNKNOWN"; 1036 break; 1037 } 1038 printf("%s[%s,%s]", pname, cmd, subcmd); 1039 return; 1040 } 1041 case BIO_READ: 1042 cmd = "READ"; 1043 break; 1044 case BIO_WRITE: 1045 cmd = "WRITE"; 1046 break; 1047 case BIO_DELETE: 1048 cmd = "DELETE"; 1049 break; 1050 default: 1051 cmd = "UNKNOWN"; 1052 printf("%s[%s()]", pname, cmd); 1053 return; 1054 } 1055 printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd, 1056 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 1057 } 1058