1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2015 by Delphix. All rights reserved. 24 * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved. 25 */ 26 27 #include <sys/sysmacros.h> 28 #include <sys/zfs_context.h> 29 #include <sys/fm/fs/zfs.h> 30 #include <sys/spa.h> 31 #include <sys/txg.h> 32 #include <sys/spa_impl.h> 33 #include <sys/vdev_impl.h> 34 #include <sys/zio_impl.h> 35 #include <sys/zio_compress.h> 36 #include <sys/zio_checksum.h> 37 #include <sys/dmu_objset.h> 38 #include <sys/arc.h> 39 #include <sys/ddt.h> 40 #include <sys/blkptr.h> 41 #include <sys/zfeature.h> 42 43 /* 44 * ========================================================================== 45 * I/O type descriptions 46 * ========================================================================== 47 */ 48 const char *zio_type_name[ZIO_TYPES] = { 49 "zio_null", "zio_read", "zio_write", "zio_free", "zio_claim", 50 "zio_ioctl" 51 }; 52 53 /* 54 * ========================================================================== 55 * I/O kmem caches 56 * ========================================================================== 57 */ 58 kmem_cache_t *zio_cache; 59 kmem_cache_t *zio_link_cache; 60 kmem_cache_t *zio_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT]; 61 kmem_cache_t *zio_data_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT]; 62 63 #ifdef _KERNEL 64 extern vmem_t *zio_alloc_arena; 65 #endif 66 67 #define ZIO_PIPELINE_CONTINUE 0x100 68 #define ZIO_PIPELINE_STOP 0x101 69 70 #define BP_SPANB(indblkshift, level) \ 71 (((uint64_t)1) << ((level) * ((indblkshift) - SPA_BLKPTRSHIFT))) 72 #define COMPARE_META_LEVEL 0x80000000ul 73 /* 74 * The following actions directly effect the spa's sync-to-convergence logic. 75 * The values below define the sync pass when we start performing the action. 76 * Care should be taken when changing these values as they directly impact 77 * spa_sync() performance. Tuning these values may introduce subtle performance 78 * pathologies and should only be done in the context of performance analysis. 79 * These tunables will eventually be removed and replaced with #defines once 80 * enough analysis has been done to determine optimal values. 81 * 82 * The 'zfs_sync_pass_deferred_free' pass must be greater than 1 to ensure that 83 * regular blocks are not deferred. 84 */ 85 int zfs_sync_pass_deferred_free = 2; /* defer frees starting in this pass */ 86 int zfs_sync_pass_dont_compress = 5; /* don't compress starting in this pass */ 87 int zfs_sync_pass_rewrite = 2; /* rewrite new bps starting in this pass */ 88 89 /* 90 * An allocating zio is one that either currently has the DVA allocate 91 * stage set or will have it later in its lifetime. 92 */ 93 #define IO_IS_ALLOCATING(zio) ((zio)->io_orig_pipeline & ZIO_STAGE_DVA_ALLOCATE) 94 95 boolean_t zio_requeue_io_start_cut_in_line = B_TRUE; 96 97 #ifdef ZFS_DEBUG 98 int zio_buf_debug_limit = 16384; 99 #else 100 int zio_buf_debug_limit = 0; 101 #endif 102 103 void 104 zio_init(void) 105 { 106 size_t c; 107 vmem_t *data_alloc_arena = NULL; 108 109 #ifdef _KERNEL 110 data_alloc_arena = zio_alloc_arena; 111 #endif 112 zio_cache = kmem_cache_create("zio_cache", 113 sizeof (zio_t), 0, NULL, NULL, NULL, NULL, NULL, 0); 114 zio_link_cache = kmem_cache_create("zio_link_cache", 115 sizeof (zio_link_t), 0, NULL, NULL, NULL, NULL, NULL, 0); 116 117 /* 118 * For small buffers, we want a cache for each multiple of 119 * SPA_MINBLOCKSIZE. For larger buffers, we want a cache 120 * for each quarter-power of 2. 121 */ 122 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) { 123 size_t size = (c + 1) << SPA_MINBLOCKSHIFT; 124 size_t p2 = size; 125 size_t align = 0; 126 size_t cflags = (size > zio_buf_debug_limit) ? KMC_NODEBUG : 0; 127 128 while (!ISP2(p2)) 129 p2 &= p2 - 1; 130 131 #ifndef _KERNEL 132 /* 133 * If we are using watchpoints, put each buffer on its own page, 134 * to eliminate the performance overhead of trapping to the 135 * kernel when modifying a non-watched buffer that shares the 136 * page with a watched buffer. 137 */ 138 if (arc_watch && !IS_P2ALIGNED(size, PAGESIZE)) 139 continue; 140 #endif 141 if (size <= 4 * SPA_MINBLOCKSIZE) { 142 align = SPA_MINBLOCKSIZE; 143 } else if (IS_P2ALIGNED(size, p2 >> 2)) { 144 align = MIN(p2 >> 2, PAGESIZE); 145 } 146 147 if (align != 0) { 148 char name[36]; 149 (void) sprintf(name, "zio_buf_%lu", (ulong_t)size); 150 zio_buf_cache[c] = kmem_cache_create(name, size, 151 align, NULL, NULL, NULL, NULL, NULL, cflags); 152 153 /* 154 * Since zio_data bufs do not appear in crash dumps, we 155 * pass KMC_NOTOUCH so that no allocator metadata is 156 * stored with the buffers. 157 */ 158 (void) sprintf(name, "zio_data_buf_%lu", (ulong_t)size); 159 zio_data_buf_cache[c] = kmem_cache_create(name, size, 160 align, NULL, NULL, NULL, NULL, data_alloc_arena, 161 cflags | KMC_NOTOUCH); 162 } 163 } 164 165 while (--c != 0) { 166 ASSERT(zio_buf_cache[c] != NULL); 167 if (zio_buf_cache[c - 1] == NULL) 168 zio_buf_cache[c - 1] = zio_buf_cache[c]; 169 170 ASSERT(zio_data_buf_cache[c] != NULL); 171 if (zio_data_buf_cache[c - 1] == NULL) 172 zio_data_buf_cache[c - 1] = zio_data_buf_cache[c]; 173 } 174 175 zio_inject_init(); 176 } 177 178 void 179 zio_fini(void) 180 { 181 size_t c; 182 kmem_cache_t *last_cache = NULL; 183 kmem_cache_t *last_data_cache = NULL; 184 185 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) { 186 if (zio_buf_cache[c] != last_cache) { 187 last_cache = zio_buf_cache[c]; 188 kmem_cache_destroy(zio_buf_cache[c]); 189 } 190 zio_buf_cache[c] = NULL; 191 192 if (zio_data_buf_cache[c] != last_data_cache) { 193 last_data_cache = zio_data_buf_cache[c]; 194 kmem_cache_destroy(zio_data_buf_cache[c]); 195 } 196 zio_data_buf_cache[c] = NULL; 197 } 198 199 kmem_cache_destroy(zio_link_cache); 200 kmem_cache_destroy(zio_cache); 201 202 zio_inject_fini(); 203 } 204 205 /* 206 * ========================================================================== 207 * Allocate and free I/O buffers 208 * ========================================================================== 209 */ 210 211 /* 212 * Use zio_buf_alloc to allocate ZFS metadata. This data will appear in a 213 * crashdump if the kernel panics, so use it judiciously. Obviously, it's 214 * useful to inspect ZFS metadata, but if possible, we should avoid keeping 215 * excess / transient data in-core during a crashdump. 216 */ 217 void * 218 zio_buf_alloc(size_t size) 219 { 220 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 221 222 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 223 224 return (kmem_cache_alloc(zio_buf_cache[c], KM_PUSHPAGE)); 225 } 226 227 /* 228 * Use zio_data_buf_alloc to allocate data. The data will not appear in a 229 * crashdump if the kernel panics. This exists so that we will limit the amount 230 * of ZFS data that shows up in a kernel crashdump. (Thus reducing the amount 231 * of kernel heap dumped to disk when the kernel panics) 232 */ 233 void * 234 zio_data_buf_alloc(size_t size) 235 { 236 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 237 238 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 239 240 return (kmem_cache_alloc(zio_data_buf_cache[c], KM_PUSHPAGE)); 241 } 242 243 void 244 zio_buf_free(void *buf, size_t size) 245 { 246 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 247 248 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 249 250 kmem_cache_free(zio_buf_cache[c], buf); 251 } 252 253 void 254 zio_data_buf_free(void *buf, size_t size) 255 { 256 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 257 258 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 259 260 kmem_cache_free(zio_data_buf_cache[c], buf); 261 } 262 263 /* 264 * ========================================================================== 265 * Push and pop I/O transform buffers 266 * ========================================================================== 267 */ 268 static void 269 zio_push_transform(zio_t *zio, void *data, uint64_t size, uint64_t bufsize, 270 zio_transform_func_t *transform) 271 { 272 zio_transform_t *zt = kmem_alloc(sizeof (zio_transform_t), KM_SLEEP); 273 274 zt->zt_orig_data = zio->io_data; 275 zt->zt_orig_size = zio->io_size; 276 zt->zt_bufsize = bufsize; 277 zt->zt_transform = transform; 278 279 zt->zt_next = zio->io_transform_stack; 280 zio->io_transform_stack = zt; 281 282 zio->io_data = data; 283 zio->io_size = size; 284 } 285 286 static void 287 zio_pop_transforms(zio_t *zio) 288 { 289 zio_transform_t *zt; 290 291 while ((zt = zio->io_transform_stack) != NULL) { 292 if (zt->zt_transform != NULL) 293 zt->zt_transform(zio, 294 zt->zt_orig_data, zt->zt_orig_size); 295 296 if (zt->zt_bufsize != 0) 297 zio_buf_free(zio->io_data, zt->zt_bufsize); 298 299 zio->io_data = zt->zt_orig_data; 300 zio->io_size = zt->zt_orig_size; 301 zio->io_transform_stack = zt->zt_next; 302 303 kmem_free(zt, sizeof (zio_transform_t)); 304 } 305 } 306 307 /* 308 * ========================================================================== 309 * I/O transform callbacks for subblocks and decompression 310 * ========================================================================== 311 */ 312 static void 313 zio_subblock(zio_t *zio, void *data, uint64_t size) 314 { 315 ASSERT(zio->io_size > size); 316 317 if (zio->io_type == ZIO_TYPE_READ) 318 bcopy(zio->io_data, data, size); 319 } 320 321 static void 322 zio_decompress(zio_t *zio, void *data, uint64_t size) 323 { 324 if (zio->io_error == 0 && 325 zio_decompress_data(BP_GET_COMPRESS(zio->io_bp), 326 zio->io_data, data, zio->io_size, size) != 0) 327 zio->io_error = SET_ERROR(EIO); 328 } 329 330 /* 331 * ========================================================================== 332 * I/O parent/child relationships and pipeline interlocks 333 * ========================================================================== 334 */ 335 /* 336 * NOTE - Callers to zio_walk_parents() and zio_walk_children must 337 * continue calling these functions until they return NULL. 338 * Otherwise, the next caller will pick up the list walk in 339 * some indeterminate state. (Otherwise every caller would 340 * have to pass in a cookie to keep the state represented by 341 * io_walk_link, which gets annoying.) 342 */ 343 zio_t * 344 zio_walk_parents(zio_t *cio) 345 { 346 zio_link_t *zl = cio->io_walk_link; 347 list_t *pl = &cio->io_parent_list; 348 349 zl = (zl == NULL) ? list_head(pl) : list_next(pl, zl); 350 cio->io_walk_link = zl; 351 352 if (zl == NULL) 353 return (NULL); 354 355 ASSERT(zl->zl_child == cio); 356 return (zl->zl_parent); 357 } 358 359 zio_t * 360 zio_walk_children(zio_t *pio) 361 { 362 zio_link_t *zl = pio->io_walk_link; 363 list_t *cl = &pio->io_child_list; 364 365 zl = (zl == NULL) ? list_head(cl) : list_next(cl, zl); 366 pio->io_walk_link = zl; 367 368 if (zl == NULL) 369 return (NULL); 370 371 ASSERT(zl->zl_parent == pio); 372 return (zl->zl_child); 373 } 374 375 zio_t * 376 zio_unique_parent(zio_t *cio) 377 { 378 zio_t *pio = zio_walk_parents(cio); 379 380 VERIFY(zio_walk_parents(cio) == NULL); 381 return (pio); 382 } 383 384 void 385 zio_add_child(zio_t *pio, zio_t *cio) 386 { 387 zio_link_t *zl = kmem_cache_alloc(zio_link_cache, KM_SLEEP); 388 389 /* 390 * Logical I/Os can have logical, gang, or vdev children. 391 * Gang I/Os can have gang or vdev children. 392 * Vdev I/Os can only have vdev children. 393 * The following ASSERT captures all of these constraints. 394 */ 395 ASSERT(cio->io_child_type <= pio->io_child_type); 396 397 zl->zl_parent = pio; 398 zl->zl_child = cio; 399 400 mutex_enter(&cio->io_lock); 401 mutex_enter(&pio->io_lock); 402 403 ASSERT(pio->io_state[ZIO_WAIT_DONE] == 0); 404 405 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 406 pio->io_children[cio->io_child_type][w] += !cio->io_state[w]; 407 408 list_insert_head(&pio->io_child_list, zl); 409 list_insert_head(&cio->io_parent_list, zl); 410 411 pio->io_child_count++; 412 cio->io_parent_count++; 413 414 mutex_exit(&pio->io_lock); 415 mutex_exit(&cio->io_lock); 416 } 417 418 static void 419 zio_remove_child(zio_t *pio, zio_t *cio, zio_link_t *zl) 420 { 421 ASSERT(zl->zl_parent == pio); 422 ASSERT(zl->zl_child == cio); 423 424 mutex_enter(&cio->io_lock); 425 mutex_enter(&pio->io_lock); 426 427 list_remove(&pio->io_child_list, zl); 428 list_remove(&cio->io_parent_list, zl); 429 430 pio->io_child_count--; 431 cio->io_parent_count--; 432 433 mutex_exit(&pio->io_lock); 434 mutex_exit(&cio->io_lock); 435 436 kmem_cache_free(zio_link_cache, zl); 437 } 438 439 static boolean_t 440 zio_wait_for_children(zio_t *zio, enum zio_child child, enum zio_wait_type wait) 441 { 442 uint64_t *countp = &zio->io_children[child][wait]; 443 boolean_t waiting = B_FALSE; 444 445 mutex_enter(&zio->io_lock); 446 ASSERT(zio->io_stall == NULL); 447 if (*countp != 0) { 448 zio->io_stage >>= 1; 449 zio->io_stall = countp; 450 waiting = B_TRUE; 451 } 452 mutex_exit(&zio->io_lock); 453 454 return (waiting); 455 } 456 457 static void 458 zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait) 459 { 460 uint64_t *countp = &pio->io_children[zio->io_child_type][wait]; 461 int *errorp = &pio->io_child_error[zio->io_child_type]; 462 463 mutex_enter(&pio->io_lock); 464 if (zio->io_error && !(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE)) 465 *errorp = zio_worst_error(*errorp, zio->io_error); 466 pio->io_reexecute |= zio->io_reexecute; 467 ASSERT3U(*countp, >, 0); 468 469 (*countp)--; 470 471 if (*countp == 0 && pio->io_stall == countp) { 472 pio->io_stall = NULL; 473 mutex_exit(&pio->io_lock); 474 zio_execute(pio); 475 } else { 476 mutex_exit(&pio->io_lock); 477 } 478 } 479 480 static void 481 zio_inherit_child_errors(zio_t *zio, enum zio_child c) 482 { 483 if (zio->io_child_error[c] != 0 && zio->io_error == 0) 484 zio->io_error = zio->io_child_error[c]; 485 } 486 487 /* 488 * ========================================================================== 489 * Create the various types of I/O (read, write, free, etc) 490 * ========================================================================== 491 */ 492 static zio_t * 493 zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, 494 void *data, uint64_t size, zio_done_func_t *done, void *private, 495 zio_type_t type, zio_priority_t priority, enum zio_flag flags, 496 vdev_t *vd, uint64_t offset, const zbookmark_phys_t *zb, 497 enum zio_stage stage, enum zio_stage pipeline) 498 { 499 zio_t *zio; 500 501 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); 502 ASSERT(P2PHASE(size, SPA_MINBLOCKSIZE) == 0); 503 ASSERT(P2PHASE(offset, SPA_MINBLOCKSIZE) == 0); 504 505 ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER)); 506 ASSERT(!bp || !(flags & ZIO_FLAG_CONFIG_WRITER)); 507 ASSERT(vd || stage == ZIO_STAGE_OPEN); 508 509 zio = kmem_cache_alloc(zio_cache, KM_SLEEP); 510 bzero(zio, sizeof (zio_t)); 511 512 mutex_init(&zio->io_lock, NULL, MUTEX_DEFAULT, NULL); 513 cv_init(&zio->io_cv, NULL, CV_DEFAULT, NULL); 514 515 list_create(&zio->io_parent_list, sizeof (zio_link_t), 516 offsetof(zio_link_t, zl_parent_node)); 517 list_create(&zio->io_child_list, sizeof (zio_link_t), 518 offsetof(zio_link_t, zl_child_node)); 519 520 if (vd != NULL) 521 zio->io_child_type = ZIO_CHILD_VDEV; 522 else if (flags & ZIO_FLAG_GANG_CHILD) 523 zio->io_child_type = ZIO_CHILD_GANG; 524 else if (flags & ZIO_FLAG_DDT_CHILD) 525 zio->io_child_type = ZIO_CHILD_DDT; 526 else 527 zio->io_child_type = ZIO_CHILD_LOGICAL; 528 529 if (bp != NULL) { 530 zio->io_bp = (blkptr_t *)bp; 531 zio->io_bp_copy = *bp; 532 zio->io_bp_orig = *bp; 533 if (type != ZIO_TYPE_WRITE || 534 zio->io_child_type == ZIO_CHILD_DDT) 535 zio->io_bp = &zio->io_bp_copy; /* so caller can free */ 536 if (zio->io_child_type == ZIO_CHILD_LOGICAL) 537 zio->io_logical = zio; 538 if (zio->io_child_type > ZIO_CHILD_GANG && BP_IS_GANG(bp)) 539 pipeline |= ZIO_GANG_STAGES; 540 } 541 542 zio->io_spa = spa; 543 zio->io_txg = txg; 544 zio->io_done = done; 545 zio->io_private = private; 546 zio->io_type = type; 547 zio->io_priority = priority; 548 zio->io_vd = vd; 549 zio->io_offset = offset; 550 zio->io_orig_data = zio->io_data = data; 551 zio->io_orig_size = zio->io_size = size; 552 zio->io_orig_flags = zio->io_flags = flags; 553 zio->io_orig_stage = zio->io_stage = stage; 554 zio->io_orig_pipeline = zio->io_pipeline = pipeline; 555 556 zio->io_state[ZIO_WAIT_READY] = (stage >= ZIO_STAGE_READY); 557 zio->io_state[ZIO_WAIT_DONE] = (stage >= ZIO_STAGE_DONE); 558 559 if (zb != NULL) 560 zio->io_bookmark = *zb; 561 562 if (pio != NULL) { 563 if (zio->io_logical == NULL) 564 zio->io_logical = pio->io_logical; 565 if (zio->io_child_type == ZIO_CHILD_GANG) 566 zio->io_gang_leader = pio->io_gang_leader; 567 zio_add_child(pio, zio); 568 } 569 570 return (zio); 571 } 572 573 static void 574 zio_destroy(zio_t *zio) 575 { 576 list_destroy(&zio->io_parent_list); 577 list_destroy(&zio->io_child_list); 578 mutex_destroy(&zio->io_lock); 579 cv_destroy(&zio->io_cv); 580 kmem_cache_free(zio_cache, zio); 581 } 582 583 zio_t * 584 zio_null(zio_t *pio, spa_t *spa, vdev_t *vd, zio_done_func_t *done, 585 void *private, enum zio_flag flags) 586 { 587 zio_t *zio; 588 589 zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private, 590 ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL, 591 ZIO_STAGE_OPEN, ZIO_INTERLOCK_PIPELINE); 592 593 return (zio); 594 } 595 596 zio_t * 597 zio_root(spa_t *spa, zio_done_func_t *done, void *private, enum zio_flag flags) 598 { 599 return (zio_null(NULL, spa, NULL, done, private, flags)); 600 } 601 602 void 603 zfs_blkptr_verify(spa_t *spa, const blkptr_t *bp) 604 { 605 if (!DMU_OT_IS_VALID(BP_GET_TYPE(bp))) { 606 zfs_panic_recover("blkptr at %p has invalid TYPE %llu", 607 bp, (longlong_t)BP_GET_TYPE(bp)); 608 } 609 if (BP_GET_CHECKSUM(bp) >= ZIO_CHECKSUM_FUNCTIONS || 610 BP_GET_CHECKSUM(bp) <= ZIO_CHECKSUM_ON) { 611 zfs_panic_recover("blkptr at %p has invalid CHECKSUM %llu", 612 bp, (longlong_t)BP_GET_CHECKSUM(bp)); 613 } 614 if (BP_GET_COMPRESS(bp) >= ZIO_COMPRESS_FUNCTIONS || 615 BP_GET_COMPRESS(bp) <= ZIO_COMPRESS_ON) { 616 zfs_panic_recover("blkptr at %p has invalid COMPRESS %llu", 617 bp, (longlong_t)BP_GET_COMPRESS(bp)); 618 } 619 if (BP_GET_LSIZE(bp) > SPA_MAXBLOCKSIZE) { 620 zfs_panic_recover("blkptr at %p has invalid LSIZE %llu", 621 bp, (longlong_t)BP_GET_LSIZE(bp)); 622 } 623 if (BP_GET_PSIZE(bp) > SPA_MAXBLOCKSIZE) { 624 zfs_panic_recover("blkptr at %p has invalid PSIZE %llu", 625 bp, (longlong_t)BP_GET_PSIZE(bp)); 626 } 627 628 if (BP_IS_EMBEDDED(bp)) { 629 if (BPE_GET_ETYPE(bp) > NUM_BP_EMBEDDED_TYPES) { 630 zfs_panic_recover("blkptr at %p has invalid ETYPE %llu", 631 bp, (longlong_t)BPE_GET_ETYPE(bp)); 632 } 633 } 634 635 /* 636 * Pool-specific checks. 637 * 638 * Note: it would be nice to verify that the blk_birth and 639 * BP_PHYSICAL_BIRTH() are not too large. However, spa_freeze() 640 * allows the birth time of log blocks (and dmu_sync()-ed blocks 641 * that are in the log) to be arbitrarily large. 642 */ 643 for (int i = 0; i < BP_GET_NDVAS(bp); i++) { 644 uint64_t vdevid = DVA_GET_VDEV(&bp->blk_dva[i]); 645 if (vdevid >= spa->spa_root_vdev->vdev_children) { 646 zfs_panic_recover("blkptr at %p DVA %u has invalid " 647 "VDEV %llu", 648 bp, i, (longlong_t)vdevid); 649 continue; 650 } 651 vdev_t *vd = spa->spa_root_vdev->vdev_child[vdevid]; 652 if (vd == NULL) { 653 zfs_panic_recover("blkptr at %p DVA %u has invalid " 654 "VDEV %llu", 655 bp, i, (longlong_t)vdevid); 656 continue; 657 } 658 if (vd->vdev_ops == &vdev_hole_ops) { 659 zfs_panic_recover("blkptr at %p DVA %u has hole " 660 "VDEV %llu", 661 bp, i, (longlong_t)vdevid); 662 continue; 663 } 664 if (vd->vdev_ops == &vdev_missing_ops) { 665 /* 666 * "missing" vdevs are valid during import, but we 667 * don't have their detailed info (e.g. asize), so 668 * we can't perform any more checks on them. 669 */ 670 continue; 671 } 672 uint64_t offset = DVA_GET_OFFSET(&bp->blk_dva[i]); 673 uint64_t asize = DVA_GET_ASIZE(&bp->blk_dva[i]); 674 if (BP_IS_GANG(bp)) 675 asize = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE); 676 if (offset + asize > vd->vdev_asize) { 677 zfs_panic_recover("blkptr at %p DVA %u has invalid " 678 "OFFSET %llu", 679 bp, i, (longlong_t)offset); 680 } 681 } 682 } 683 684 zio_t * 685 zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, 686 void *data, uint64_t size, zio_done_func_t *done, void *private, 687 zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb) 688 { 689 zio_t *zio; 690 691 zfs_blkptr_verify(spa, bp); 692 693 zio = zio_create(pio, spa, BP_PHYSICAL_BIRTH(bp), bp, 694 data, size, done, private, 695 ZIO_TYPE_READ, priority, flags, NULL, 0, zb, 696 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ? 697 ZIO_DDT_CHILD_READ_PIPELINE : ZIO_READ_PIPELINE); 698 699 return (zio); 700 } 701 702 zio_t * 703 zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, 704 void *data, uint64_t size, const zio_prop_t *zp, 705 zio_done_func_t *ready, zio_done_func_t *physdone, zio_done_func_t *done, 706 void *private, 707 zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb) 708 { 709 zio_t *zio; 710 711 ASSERT(zp->zp_checksum >= ZIO_CHECKSUM_OFF && 712 zp->zp_checksum < ZIO_CHECKSUM_FUNCTIONS && 713 zp->zp_compress >= ZIO_COMPRESS_OFF && 714 zp->zp_compress < ZIO_COMPRESS_FUNCTIONS && 715 DMU_OT_IS_VALID(zp->zp_type) && 716 zp->zp_level < 32 && 717 zp->zp_copies > 0 && 718 zp->zp_copies <= spa_max_replication(spa)); 719 720 zio = zio_create(pio, spa, txg, bp, data, size, done, private, 721 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb, 722 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ? 723 ZIO_DDT_CHILD_WRITE_PIPELINE : ZIO_WRITE_PIPELINE); 724 725 zio->io_ready = ready; 726 zio->io_physdone = physdone; 727 zio->io_prop = *zp; 728 729 /* 730 * Data can be NULL if we are going to call zio_write_override() to 731 * provide the already-allocated BP. But we may need the data to 732 * verify a dedup hit (if requested). In this case, don't try to 733 * dedup (just take the already-allocated BP verbatim). 734 */ 735 if (data == NULL && zio->io_prop.zp_dedup_verify) { 736 zio->io_prop.zp_dedup = zio->io_prop.zp_dedup_verify = B_FALSE; 737 } 738 739 return (zio); 740 } 741 742 zio_t * 743 zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, void *data, 744 uint64_t size, zio_done_func_t *done, void *private, 745 zio_priority_t priority, enum zio_flag flags, zbookmark_phys_t *zb) 746 { 747 zio_t *zio; 748 749 zio = zio_create(pio, spa, txg, bp, data, size, done, private, 750 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb, 751 ZIO_STAGE_OPEN, ZIO_REWRITE_PIPELINE); 752 753 return (zio); 754 } 755 756 void 757 zio_write_override(zio_t *zio, blkptr_t *bp, int copies, boolean_t nopwrite) 758 { 759 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 760 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 761 ASSERT(zio->io_stage == ZIO_STAGE_OPEN); 762 ASSERT(zio->io_txg == spa_syncing_txg(zio->io_spa)); 763 764 /* 765 * We must reset the io_prop to match the values that existed 766 * when the bp was first written by dmu_sync() keeping in mind 767 * that nopwrite and dedup are mutually exclusive. 768 */ 769 zio->io_prop.zp_dedup = nopwrite ? B_FALSE : zio->io_prop.zp_dedup; 770 zio->io_prop.zp_nopwrite = nopwrite; 771 zio->io_prop.zp_copies = copies; 772 zio->io_bp_override = bp; 773 } 774 775 void 776 zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp) 777 { 778 779 /* 780 * The check for EMBEDDED is a performance optimization. We 781 * process the free here (by ignoring it) rather than 782 * putting it on the list and then processing it in zio_free_sync(). 783 */ 784 if (BP_IS_EMBEDDED(bp)) 785 return; 786 metaslab_check_free(spa, bp); 787 788 /* 789 * Frees that are for the currently-syncing txg, are not going to be 790 * deferred, and which will not need to do a read (i.e. not GANG or 791 * DEDUP), can be processed immediately. Otherwise, put them on the 792 * in-memory list for later processing. 793 */ 794 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp) || 795 txg != spa->spa_syncing_txg || 796 spa_sync_pass(spa) >= zfs_sync_pass_deferred_free) { 797 bplist_append(&spa->spa_free_bplist[txg & TXG_MASK], bp); 798 } else { 799 VERIFY0(zio_wait(zio_free_sync(NULL, spa, txg, bp, 0))); 800 } 801 } 802 803 zio_t * 804 zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, 805 enum zio_flag flags) 806 { 807 zio_t *zio; 808 enum zio_stage stage = ZIO_FREE_PIPELINE; 809 810 ASSERT(!BP_IS_HOLE(bp)); 811 ASSERT(spa_syncing_txg(spa) == txg); 812 ASSERT(spa_sync_pass(spa) < zfs_sync_pass_deferred_free); 813 814 if (BP_IS_EMBEDDED(bp)) 815 return (zio_null(pio, spa, NULL, NULL, NULL, 0)); 816 817 metaslab_check_free(spa, bp); 818 arc_freed(spa, bp); 819 820 /* 821 * GANG and DEDUP blocks can induce a read (for the gang block header, 822 * or the DDT), so issue them asynchronously so that this thread is 823 * not tied up. 824 */ 825 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp)) 826 stage |= ZIO_STAGE_ISSUE_ASYNC; 827 828 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp), 829 NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_NOW, flags, 830 NULL, 0, NULL, ZIO_STAGE_OPEN, stage); 831 832 return (zio); 833 } 834 835 zio_t * 836 zio_claim(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, 837 zio_done_func_t *done, void *private, enum zio_flag flags) 838 { 839 zio_t *zio; 840 841 dprintf_bp(bp, "claiming in txg %llu", txg); 842 843 if (BP_IS_EMBEDDED(bp)) 844 return (zio_null(pio, spa, NULL, NULL, NULL, 0)); 845 846 /* 847 * A claim is an allocation of a specific block. Claims are needed 848 * to support immediate writes in the intent log. The issue is that 849 * immediate writes contain committed data, but in a txg that was 850 * *not* committed. Upon opening the pool after an unclean shutdown, 851 * the intent log claims all blocks that contain immediate write data 852 * so that the SPA knows they're in use. 853 * 854 * All claims *must* be resolved in the first txg -- before the SPA 855 * starts allocating blocks -- so that nothing is allocated twice. 856 * If txg == 0 we just verify that the block is claimable. 857 */ 858 ASSERT3U(spa->spa_uberblock.ub_rootbp.blk_birth, <, spa_first_txg(spa)); 859 ASSERT(txg == spa_first_txg(spa) || txg == 0); 860 ASSERT(!BP_GET_DEDUP(bp) || !spa_writeable(spa)); /* zdb(1M) */ 861 862 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp), 863 done, private, ZIO_TYPE_CLAIM, ZIO_PRIORITY_NOW, flags, 864 NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_CLAIM_PIPELINE); 865 866 return (zio); 867 } 868 869 zio_t * 870 zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd, 871 zio_done_func_t *done, void *private, enum zio_flag flags) 872 { 873 zio_t *zio; 874 int c; 875 876 if (vd->vdev_children == 0) { 877 zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private, 878 ZIO_TYPE_IOCTL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL, 879 ZIO_STAGE_OPEN, ZIO_IOCTL_PIPELINE); 880 881 zio->io_cmd = cmd; 882 } else { 883 zio = zio_null(pio, spa, NULL, NULL, NULL, flags); 884 885 for (c = 0; c < vd->vdev_children; c++) 886 zio_nowait(zio_ioctl(zio, spa, vd->vdev_child[c], cmd, 887 done, private, flags)); 888 } 889 890 return (zio); 891 } 892 893 zio_t * 894 zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, 895 void *data, int checksum, zio_done_func_t *done, void *private, 896 zio_priority_t priority, enum zio_flag flags, boolean_t labels) 897 { 898 zio_t *zio; 899 900 ASSERT(vd->vdev_children == 0); 901 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE || 902 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE); 903 ASSERT3U(offset + size, <=, vd->vdev_psize); 904 905 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private, 906 ZIO_TYPE_READ, priority, flags | ZIO_FLAG_PHYSICAL, vd, offset, 907 NULL, ZIO_STAGE_OPEN, ZIO_READ_PHYS_PIPELINE); 908 909 zio->io_prop.zp_checksum = checksum; 910 911 return (zio); 912 } 913 914 zio_t * 915 zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, 916 void *data, int checksum, zio_done_func_t *done, void *private, 917 zio_priority_t priority, enum zio_flag flags, boolean_t labels) 918 { 919 zio_t *zio; 920 921 ASSERT(vd->vdev_children == 0); 922 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE || 923 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE); 924 ASSERT3U(offset + size, <=, vd->vdev_psize); 925 926 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private, 927 ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_PHYSICAL, vd, offset, 928 NULL, ZIO_STAGE_OPEN, ZIO_WRITE_PHYS_PIPELINE); 929 930 zio->io_prop.zp_checksum = checksum; 931 932 if (zio_checksum_table[checksum].ci_flags & ZCHECKSUM_FLAG_EMBEDDED) { 933 /* 934 * zec checksums are necessarily destructive -- they modify 935 * the end of the write buffer to hold the verifier/checksum. 936 * Therefore, we must make a local copy in case the data is 937 * being written to multiple places in parallel. 938 */ 939 void *wbuf = zio_buf_alloc(size); 940 bcopy(data, wbuf, size); 941 zio_push_transform(zio, wbuf, size, size, NULL); 942 } 943 944 return (zio); 945 } 946 947 /* 948 * Create a child I/O to do some work for us. 949 */ 950 zio_t * 951 zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset, 952 void *data, uint64_t size, int type, zio_priority_t priority, 953 enum zio_flag flags, zio_done_func_t *done, void *private) 954 { 955 enum zio_stage pipeline = ZIO_VDEV_CHILD_PIPELINE; 956 zio_t *zio; 957 958 ASSERT(vd->vdev_parent == 959 (pio->io_vd ? pio->io_vd : pio->io_spa->spa_root_vdev)); 960 961 if (type == ZIO_TYPE_READ && bp != NULL) { 962 /* 963 * If we have the bp, then the child should perform the 964 * checksum and the parent need not. This pushes error 965 * detection as close to the leaves as possible and 966 * eliminates redundant checksums in the interior nodes. 967 */ 968 pipeline |= ZIO_STAGE_CHECKSUM_VERIFY; 969 pio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY; 970 } 971 972 if (vd->vdev_children == 0) 973 offset += VDEV_LABEL_START_SIZE; 974 975 flags |= ZIO_VDEV_CHILD_FLAGS(pio) | ZIO_FLAG_DONT_PROPAGATE; 976 977 /* 978 * If we've decided to do a repair, the write is not speculative -- 979 * even if the original read was. 980 */ 981 if (flags & ZIO_FLAG_IO_REPAIR) 982 flags &= ~ZIO_FLAG_SPECULATIVE; 983 984 zio = zio_create(pio, pio->io_spa, pio->io_txg, bp, data, size, 985 done, private, type, priority, flags, vd, offset, &pio->io_bookmark, 986 ZIO_STAGE_VDEV_IO_START >> 1, pipeline); 987 988 zio->io_physdone = pio->io_physdone; 989 if (vd->vdev_ops->vdev_op_leaf && zio->io_logical != NULL) 990 zio->io_logical->io_phys_children++; 991 992 return (zio); 993 } 994 995 zio_t * 996 zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, void *data, uint64_t size, 997 int type, zio_priority_t priority, enum zio_flag flags, 998 zio_done_func_t *done, void *private) 999 { 1000 zio_t *zio; 1001 1002 ASSERT(vd->vdev_ops->vdev_op_leaf); 1003 1004 zio = zio_create(NULL, vd->vdev_spa, 0, NULL, 1005 data, size, done, private, type, priority, 1006 flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY | ZIO_FLAG_DELEGATED, 1007 vd, offset, NULL, 1008 ZIO_STAGE_VDEV_IO_START >> 1, ZIO_VDEV_CHILD_PIPELINE); 1009 1010 return (zio); 1011 } 1012 1013 void 1014 zio_flush(zio_t *zio, vdev_t *vd) 1015 { 1016 zio_nowait(zio_ioctl(zio, zio->io_spa, vd, DKIOCFLUSHWRITECACHE, 1017 NULL, NULL, 1018 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_DONT_RETRY)); 1019 } 1020 1021 void 1022 zio_shrink(zio_t *zio, uint64_t size) 1023 { 1024 ASSERT(zio->io_executor == NULL); 1025 ASSERT(zio->io_orig_size == zio->io_size); 1026 ASSERT(size <= zio->io_size); 1027 1028 /* 1029 * We don't shrink for raidz because of problems with the 1030 * reconstruction when reading back less than the block size. 1031 * Note, BP_IS_RAIDZ() assumes no compression. 1032 */ 1033 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); 1034 if (!BP_IS_RAIDZ(zio->io_bp)) 1035 zio->io_orig_size = zio->io_size = size; 1036 } 1037 1038 /* 1039 * ========================================================================== 1040 * Prepare to read and write logical blocks 1041 * ========================================================================== 1042 */ 1043 1044 static int 1045 zio_read_bp_init(zio_t *zio) 1046 { 1047 blkptr_t *bp = zio->io_bp; 1048 1049 if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF && 1050 zio->io_child_type == ZIO_CHILD_LOGICAL && 1051 !(zio->io_flags & ZIO_FLAG_RAW)) { 1052 uint64_t psize = 1053 BP_IS_EMBEDDED(bp) ? BPE_GET_PSIZE(bp) : BP_GET_PSIZE(bp); 1054 void *cbuf = zio_buf_alloc(psize); 1055 1056 zio_push_transform(zio, cbuf, psize, psize, zio_decompress); 1057 } 1058 1059 if (BP_IS_EMBEDDED(bp) && BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA) { 1060 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1061 decode_embedded_bp_compressed(bp, zio->io_data); 1062 } else { 1063 ASSERT(!BP_IS_EMBEDDED(bp)); 1064 } 1065 1066 if (!DMU_OT_IS_METADATA(BP_GET_TYPE(bp)) && BP_GET_LEVEL(bp) == 0) 1067 zio->io_flags |= ZIO_FLAG_DONT_CACHE; 1068 1069 if (BP_GET_TYPE(bp) == DMU_OT_DDT_ZAP) 1070 zio->io_flags |= ZIO_FLAG_DONT_CACHE; 1071 1072 if (BP_GET_DEDUP(bp) && zio->io_child_type == ZIO_CHILD_LOGICAL) 1073 zio->io_pipeline = ZIO_DDT_READ_PIPELINE; 1074 1075 return (ZIO_PIPELINE_CONTINUE); 1076 } 1077 1078 static int 1079 zio_write_bp_init(zio_t *zio) 1080 { 1081 spa_t *spa = zio->io_spa; 1082 zio_prop_t *zp = &zio->io_prop; 1083 enum zio_compress compress = zp->zp_compress; 1084 blkptr_t *bp = zio->io_bp; 1085 uint64_t lsize = zio->io_size; 1086 uint64_t psize = lsize; 1087 int pass = 1; 1088 1089 /* 1090 * If our children haven't all reached the ready stage, 1091 * wait for them and then repeat this pipeline stage. 1092 */ 1093 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) || 1094 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_READY)) 1095 return (ZIO_PIPELINE_STOP); 1096 1097 if (!IO_IS_ALLOCATING(zio)) 1098 return (ZIO_PIPELINE_CONTINUE); 1099 1100 ASSERT(zio->io_child_type != ZIO_CHILD_DDT); 1101 1102 if (zio->io_bp_override) { 1103 ASSERT(bp->blk_birth != zio->io_txg); 1104 ASSERT(BP_GET_DEDUP(zio->io_bp_override) == 0); 1105 1106 *bp = *zio->io_bp_override; 1107 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1108 1109 if (BP_IS_EMBEDDED(bp)) 1110 return (ZIO_PIPELINE_CONTINUE); 1111 1112 /* 1113 * If we've been overridden and nopwrite is set then 1114 * set the flag accordingly to indicate that a nopwrite 1115 * has already occurred. 1116 */ 1117 if (!BP_IS_HOLE(bp) && zp->zp_nopwrite) { 1118 ASSERT(!zp->zp_dedup); 1119 zio->io_flags |= ZIO_FLAG_NOPWRITE; 1120 return (ZIO_PIPELINE_CONTINUE); 1121 } 1122 1123 ASSERT(!zp->zp_nopwrite); 1124 1125 if (BP_IS_HOLE(bp) || !zp->zp_dedup) 1126 return (ZIO_PIPELINE_CONTINUE); 1127 1128 ASSERT((zio_checksum_table[zp->zp_checksum].ci_flags & 1129 ZCHECKSUM_FLAG_DEDUP) || zp->zp_dedup_verify); 1130 1131 if (BP_GET_CHECKSUM(bp) == zp->zp_checksum) { 1132 BP_SET_DEDUP(bp, 1); 1133 zio->io_pipeline |= ZIO_STAGE_DDT_WRITE; 1134 return (ZIO_PIPELINE_CONTINUE); 1135 } 1136 zio->io_bp_override = NULL; 1137 BP_ZERO(bp); 1138 } 1139 1140 if (!BP_IS_HOLE(bp) && bp->blk_birth == zio->io_txg) { 1141 /* 1142 * We're rewriting an existing block, which means we're 1143 * working on behalf of spa_sync(). For spa_sync() to 1144 * converge, it must eventually be the case that we don't 1145 * have to allocate new blocks. But compression changes 1146 * the blocksize, which forces a reallocate, and makes 1147 * convergence take longer. Therefore, after the first 1148 * few passes, stop compressing to ensure convergence. 1149 */ 1150 pass = spa_sync_pass(spa); 1151 1152 ASSERT(zio->io_txg == spa_syncing_txg(spa)); 1153 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 1154 ASSERT(!BP_GET_DEDUP(bp)); 1155 1156 if (pass >= zfs_sync_pass_dont_compress) 1157 compress = ZIO_COMPRESS_OFF; 1158 1159 /* Make sure someone doesn't change their mind on overwrites */ 1160 ASSERT(BP_IS_EMBEDDED(bp) || MIN(zp->zp_copies + BP_IS_GANG(bp), 1161 spa_max_replication(spa)) == BP_GET_NDVAS(bp)); 1162 } 1163 1164 if (compress != ZIO_COMPRESS_OFF) { 1165 void *cbuf = zio_buf_alloc(lsize); 1166 psize = zio_compress_data(compress, zio->io_data, cbuf, lsize); 1167 if (psize == 0 || psize == lsize) { 1168 compress = ZIO_COMPRESS_OFF; 1169 zio_buf_free(cbuf, lsize); 1170 } else if (!zp->zp_dedup && psize <= BPE_PAYLOAD_SIZE && 1171 zp->zp_level == 0 && !DMU_OT_HAS_FILL(zp->zp_type) && 1172 spa_feature_is_enabled(spa, SPA_FEATURE_EMBEDDED_DATA)) { 1173 encode_embedded_bp_compressed(bp, 1174 cbuf, compress, lsize, psize); 1175 BPE_SET_ETYPE(bp, BP_EMBEDDED_TYPE_DATA); 1176 BP_SET_TYPE(bp, zio->io_prop.zp_type); 1177 BP_SET_LEVEL(bp, zio->io_prop.zp_level); 1178 zio_buf_free(cbuf, lsize); 1179 bp->blk_birth = zio->io_txg; 1180 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1181 ASSERT(spa_feature_is_active(spa, 1182 SPA_FEATURE_EMBEDDED_DATA)); 1183 return (ZIO_PIPELINE_CONTINUE); 1184 } else { 1185 /* 1186 * Round up compressed size up to the ashift 1187 * of the smallest-ashift device, and zero the tail. 1188 * This ensures that the compressed size of the BP 1189 * (and thus compressratio property) are correct, 1190 * in that we charge for the padding used to fill out 1191 * the last sector. 1192 */ 1193 ASSERT3U(spa->spa_min_ashift, >=, SPA_MINBLOCKSHIFT); 1194 size_t rounded = (size_t)P2ROUNDUP(psize, 1195 1ULL << spa->spa_min_ashift); 1196 if (rounded >= lsize) { 1197 compress = ZIO_COMPRESS_OFF; 1198 zio_buf_free(cbuf, lsize); 1199 psize = lsize; 1200 } else { 1201 bzero((char *)cbuf + psize, rounded - psize); 1202 psize = rounded; 1203 zio_push_transform(zio, cbuf, 1204 psize, lsize, NULL); 1205 } 1206 } 1207 } 1208 1209 /* 1210 * The final pass of spa_sync() must be all rewrites, but the first 1211 * few passes offer a trade-off: allocating blocks defers convergence, 1212 * but newly allocated blocks are sequential, so they can be written 1213 * to disk faster. Therefore, we allow the first few passes of 1214 * spa_sync() to allocate new blocks, but force rewrites after that. 1215 * There should only be a handful of blocks after pass 1 in any case. 1216 */ 1217 if (!BP_IS_HOLE(bp) && bp->blk_birth == zio->io_txg && 1218 BP_GET_PSIZE(bp) == psize && 1219 pass >= zfs_sync_pass_rewrite) { 1220 ASSERT(psize != 0); 1221 enum zio_stage gang_stages = zio->io_pipeline & ZIO_GANG_STAGES; 1222 zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages; 1223 zio->io_flags |= ZIO_FLAG_IO_REWRITE; 1224 } else { 1225 BP_ZERO(bp); 1226 zio->io_pipeline = ZIO_WRITE_PIPELINE; 1227 } 1228 1229 if (psize == 0) { 1230 if (zio->io_bp_orig.blk_birth != 0 && 1231 spa_feature_is_active(spa, SPA_FEATURE_HOLE_BIRTH)) { 1232 BP_SET_LSIZE(bp, lsize); 1233 BP_SET_TYPE(bp, zp->zp_type); 1234 BP_SET_LEVEL(bp, zp->zp_level); 1235 BP_SET_BIRTH(bp, zio->io_txg, 0); 1236 } 1237 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1238 } else { 1239 ASSERT(zp->zp_checksum != ZIO_CHECKSUM_GANG_HEADER); 1240 BP_SET_LSIZE(bp, lsize); 1241 BP_SET_TYPE(bp, zp->zp_type); 1242 BP_SET_LEVEL(bp, zp->zp_level); 1243 BP_SET_PSIZE(bp, psize); 1244 BP_SET_COMPRESS(bp, compress); 1245 BP_SET_CHECKSUM(bp, zp->zp_checksum); 1246 BP_SET_DEDUP(bp, zp->zp_dedup); 1247 BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER); 1248 if (zp->zp_dedup) { 1249 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 1250 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 1251 zio->io_pipeline = ZIO_DDT_WRITE_PIPELINE; 1252 } 1253 if (zp->zp_nopwrite) { 1254 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 1255 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 1256 zio->io_pipeline |= ZIO_STAGE_NOP_WRITE; 1257 } 1258 } 1259 1260 return (ZIO_PIPELINE_CONTINUE); 1261 } 1262 1263 static int 1264 zio_free_bp_init(zio_t *zio) 1265 { 1266 blkptr_t *bp = zio->io_bp; 1267 1268 if (zio->io_child_type == ZIO_CHILD_LOGICAL) { 1269 if (BP_GET_DEDUP(bp)) 1270 zio->io_pipeline = ZIO_DDT_FREE_PIPELINE; 1271 } 1272 1273 return (ZIO_PIPELINE_CONTINUE); 1274 } 1275 1276 /* 1277 * ========================================================================== 1278 * Execute the I/O pipeline 1279 * ========================================================================== 1280 */ 1281 1282 static void 1283 zio_taskq_dispatch(zio_t *zio, zio_taskq_type_t q, boolean_t cutinline) 1284 { 1285 spa_t *spa = zio->io_spa; 1286 zio_type_t t = zio->io_type; 1287 int flags = (cutinline ? TQ_FRONT : 0); 1288 1289 /* 1290 * If we're a config writer or a probe, the normal issue and 1291 * interrupt threads may all be blocked waiting for the config lock. 1292 * In this case, select the otherwise-unused taskq for ZIO_TYPE_NULL. 1293 */ 1294 if (zio->io_flags & (ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_PROBE)) 1295 t = ZIO_TYPE_NULL; 1296 1297 /* 1298 * A similar issue exists for the L2ARC write thread until L2ARC 2.0. 1299 */ 1300 if (t == ZIO_TYPE_WRITE && zio->io_vd && zio->io_vd->vdev_aux) 1301 t = ZIO_TYPE_NULL; 1302 1303 /* 1304 * If this is a high priority I/O, then use the high priority taskq if 1305 * available. 1306 */ 1307 if (zio->io_priority == ZIO_PRIORITY_NOW && 1308 spa->spa_zio_taskq[t][q + 1].stqs_count != 0) 1309 q++; 1310 1311 ASSERT3U(q, <, ZIO_TASKQ_TYPES); 1312 1313 /* 1314 * NB: We are assuming that the zio can only be dispatched 1315 * to a single taskq at a time. It would be a grievous error 1316 * to dispatch the zio to another taskq at the same time. 1317 */ 1318 ASSERT(zio->io_tqent.tqent_next == NULL); 1319 spa_taskq_dispatch_ent(spa, t, q, (task_func_t *)zio_execute, zio, 1320 flags, &zio->io_tqent); 1321 } 1322 1323 static boolean_t 1324 zio_taskq_member(zio_t *zio, zio_taskq_type_t q) 1325 { 1326 kthread_t *executor = zio->io_executor; 1327 spa_t *spa = zio->io_spa; 1328 1329 for (zio_type_t t = 0; t < ZIO_TYPES; t++) { 1330 spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q]; 1331 uint_t i; 1332 for (i = 0; i < tqs->stqs_count; i++) { 1333 if (taskq_member(tqs->stqs_taskq[i], executor)) 1334 return (B_TRUE); 1335 } 1336 } 1337 1338 return (B_FALSE); 1339 } 1340 1341 static int 1342 zio_issue_async(zio_t *zio) 1343 { 1344 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE); 1345 1346 return (ZIO_PIPELINE_STOP); 1347 } 1348 1349 void 1350 zio_interrupt(zio_t *zio) 1351 { 1352 zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT, B_FALSE); 1353 } 1354 1355 /* 1356 * Execute the I/O pipeline until one of the following occurs: 1357 * 1358 * (1) the I/O completes 1359 * (2) the pipeline stalls waiting for dependent child I/Os 1360 * (3) the I/O issues, so we're waiting for an I/O completion interrupt 1361 * (4) the I/O is delegated by vdev-level caching or aggregation 1362 * (5) the I/O is deferred due to vdev-level queueing 1363 * (6) the I/O is handed off to another thread. 1364 * 1365 * In all cases, the pipeline stops whenever there's no CPU work; it never 1366 * burns a thread in cv_wait(). 1367 * 1368 * There's no locking on io_stage because there's no legitimate way 1369 * for multiple threads to be attempting to process the same I/O. 1370 */ 1371 static zio_pipe_stage_t *zio_pipeline[]; 1372 1373 void 1374 zio_execute(zio_t *zio) 1375 { 1376 zio->io_executor = curthread; 1377 1378 while (zio->io_stage < ZIO_STAGE_DONE) { 1379 enum zio_stage pipeline = zio->io_pipeline; 1380 enum zio_stage stage = zio->io_stage; 1381 int rv; 1382 1383 ASSERT(!MUTEX_HELD(&zio->io_lock)); 1384 ASSERT(ISP2(stage)); 1385 ASSERT(zio->io_stall == NULL); 1386 1387 do { 1388 stage <<= 1; 1389 } while ((stage & pipeline) == 0); 1390 1391 ASSERT(stage <= ZIO_STAGE_DONE); 1392 1393 /* 1394 * If we are in interrupt context and this pipeline stage 1395 * will grab a config lock that is held across I/O, 1396 * or may wait for an I/O that needs an interrupt thread 1397 * to complete, issue async to avoid deadlock. 1398 * 1399 * For VDEV_IO_START, we cut in line so that the io will 1400 * be sent to disk promptly. 1401 */ 1402 if ((stage & ZIO_BLOCKING_STAGES) && zio->io_vd == NULL && 1403 zio_taskq_member(zio, ZIO_TASKQ_INTERRUPT)) { 1404 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ? 1405 zio_requeue_io_start_cut_in_line : B_FALSE; 1406 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut); 1407 return; 1408 } 1409 1410 zio->io_stage = stage; 1411 rv = zio_pipeline[highbit64(stage) - 1](zio); 1412 1413 if (rv == ZIO_PIPELINE_STOP) 1414 return; 1415 1416 ASSERT(rv == ZIO_PIPELINE_CONTINUE); 1417 } 1418 } 1419 1420 /* 1421 * ========================================================================== 1422 * Initiate I/O, either sync or async 1423 * ========================================================================== 1424 */ 1425 int 1426 zio_wait(zio_t *zio) 1427 { 1428 int error; 1429 1430 ASSERT(zio->io_stage == ZIO_STAGE_OPEN); 1431 ASSERT(zio->io_executor == NULL); 1432 1433 zio->io_waiter = curthread; 1434 1435 zio_execute(zio); 1436 1437 mutex_enter(&zio->io_lock); 1438 while (zio->io_executor != NULL) 1439 cv_wait(&zio->io_cv, &zio->io_lock); 1440 mutex_exit(&zio->io_lock); 1441 1442 error = zio->io_error; 1443 zio_destroy(zio); 1444 1445 return (error); 1446 } 1447 1448 void 1449 zio_nowait(zio_t *zio) 1450 { 1451 ASSERT(zio->io_executor == NULL); 1452 1453 if (zio->io_child_type == ZIO_CHILD_LOGICAL && 1454 zio_unique_parent(zio) == NULL) { 1455 /* 1456 * This is a logical async I/O with no parent to wait for it. 1457 * We add it to the spa_async_root_zio "Godfather" I/O which 1458 * will ensure they complete prior to unloading the pool. 1459 */ 1460 spa_t *spa = zio->io_spa; 1461 1462 zio_add_child(spa->spa_async_zio_root[CPU_SEQID], zio); 1463 } 1464 1465 zio_execute(zio); 1466 } 1467 1468 /* 1469 * ========================================================================== 1470 * Reexecute or suspend/resume failed I/O 1471 * ========================================================================== 1472 */ 1473 1474 static void 1475 zio_reexecute(zio_t *pio) 1476 { 1477 zio_t *cio, *cio_next; 1478 1479 ASSERT(pio->io_child_type == ZIO_CHILD_LOGICAL); 1480 ASSERT(pio->io_orig_stage == ZIO_STAGE_OPEN); 1481 ASSERT(pio->io_gang_leader == NULL); 1482 ASSERT(pio->io_gang_tree == NULL); 1483 1484 pio->io_flags = pio->io_orig_flags; 1485 pio->io_stage = pio->io_orig_stage; 1486 pio->io_pipeline = pio->io_orig_pipeline; 1487 pio->io_reexecute = 0; 1488 pio->io_flags |= ZIO_FLAG_REEXECUTED; 1489 pio->io_error = 0; 1490 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 1491 pio->io_state[w] = 0; 1492 for (int c = 0; c < ZIO_CHILD_TYPES; c++) 1493 pio->io_child_error[c] = 0; 1494 1495 if (IO_IS_ALLOCATING(pio)) 1496 BP_ZERO(pio->io_bp); 1497 1498 /* 1499 * As we reexecute pio's children, new children could be created. 1500 * New children go to the head of pio's io_child_list, however, 1501 * so we will (correctly) not reexecute them. The key is that 1502 * the remainder of pio's io_child_list, from 'cio_next' onward, 1503 * cannot be affected by any side effects of reexecuting 'cio'. 1504 */ 1505 for (cio = zio_walk_children(pio); cio != NULL; cio = cio_next) { 1506 cio_next = zio_walk_children(pio); 1507 mutex_enter(&pio->io_lock); 1508 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 1509 pio->io_children[cio->io_child_type][w]++; 1510 mutex_exit(&pio->io_lock); 1511 zio_reexecute(cio); 1512 } 1513 1514 /* 1515 * Now that all children have been reexecuted, execute the parent. 1516 * We don't reexecute "The Godfather" I/O here as it's the 1517 * responsibility of the caller to wait on him. 1518 */ 1519 if (!(pio->io_flags & ZIO_FLAG_GODFATHER)) 1520 zio_execute(pio); 1521 } 1522 1523 void 1524 zio_suspend(spa_t *spa, zio_t *zio) 1525 { 1526 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC) 1527 fm_panic("Pool '%s' has encountered an uncorrectable I/O " 1528 "failure and the failure mode property for this pool " 1529 "is set to panic.", spa_name(spa)); 1530 1531 zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, NULL, 0, 0); 1532 1533 mutex_enter(&spa->spa_suspend_lock); 1534 1535 if (spa->spa_suspend_zio_root == NULL) 1536 spa->spa_suspend_zio_root = zio_root(spa, NULL, NULL, 1537 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | 1538 ZIO_FLAG_GODFATHER); 1539 1540 spa->spa_suspended = B_TRUE; 1541 1542 if (zio != NULL) { 1543 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER)); 1544 ASSERT(zio != spa->spa_suspend_zio_root); 1545 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 1546 ASSERT(zio_unique_parent(zio) == NULL); 1547 ASSERT(zio->io_stage == ZIO_STAGE_DONE); 1548 zio_add_child(spa->spa_suspend_zio_root, zio); 1549 } 1550 1551 mutex_exit(&spa->spa_suspend_lock); 1552 } 1553 1554 int 1555 zio_resume(spa_t *spa) 1556 { 1557 zio_t *pio; 1558 1559 /* 1560 * Reexecute all previously suspended i/o. 1561 */ 1562 mutex_enter(&spa->spa_suspend_lock); 1563 spa->spa_suspended = B_FALSE; 1564 cv_broadcast(&spa->spa_suspend_cv); 1565 pio = spa->spa_suspend_zio_root; 1566 spa->spa_suspend_zio_root = NULL; 1567 mutex_exit(&spa->spa_suspend_lock); 1568 1569 if (pio == NULL) 1570 return (0); 1571 1572 zio_reexecute(pio); 1573 return (zio_wait(pio)); 1574 } 1575 1576 void 1577 zio_resume_wait(spa_t *spa) 1578 { 1579 mutex_enter(&spa->spa_suspend_lock); 1580 while (spa_suspended(spa)) 1581 cv_wait(&spa->spa_suspend_cv, &spa->spa_suspend_lock); 1582 mutex_exit(&spa->spa_suspend_lock); 1583 } 1584 1585 /* 1586 * ========================================================================== 1587 * Gang blocks. 1588 * 1589 * A gang block is a collection of small blocks that looks to the DMU 1590 * like one large block. When zio_dva_allocate() cannot find a block 1591 * of the requested size, due to either severe fragmentation or the pool 1592 * being nearly full, it calls zio_write_gang_block() to construct the 1593 * block from smaller fragments. 1594 * 1595 * A gang block consists of a gang header (zio_gbh_phys_t) and up to 1596 * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like 1597 * an indirect block: it's an array of block pointers. It consumes 1598 * only one sector and hence is allocatable regardless of fragmentation. 1599 * The gang header's bps point to its gang members, which hold the data. 1600 * 1601 * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg> 1602 * as the verifier to ensure uniqueness of the SHA256 checksum. 1603 * Critically, the gang block bp's blk_cksum is the checksum of the data, 1604 * not the gang header. This ensures that data block signatures (needed for 1605 * deduplication) are independent of how the block is physically stored. 1606 * 1607 * Gang blocks can be nested: a gang member may itself be a gang block. 1608 * Thus every gang block is a tree in which root and all interior nodes are 1609 * gang headers, and the leaves are normal blocks that contain user data. 1610 * The root of the gang tree is called the gang leader. 1611 * 1612 * To perform any operation (read, rewrite, free, claim) on a gang block, 1613 * zio_gang_assemble() first assembles the gang tree (minus data leaves) 1614 * in the io_gang_tree field of the original logical i/o by recursively 1615 * reading the gang leader and all gang headers below it. This yields 1616 * an in-core tree containing the contents of every gang header and the 1617 * bps for every constituent of the gang block. 1618 * 1619 * With the gang tree now assembled, zio_gang_issue() just walks the gang tree 1620 * and invokes a callback on each bp. To free a gang block, zio_gang_issue() 1621 * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp. 1622 * zio_claim_gang() provides a similarly trivial wrapper for zio_claim(). 1623 * zio_read_gang() is a wrapper around zio_read() that omits reading gang 1624 * headers, since we already have those in io_gang_tree. zio_rewrite_gang() 1625 * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite() 1626 * of the gang header plus zio_checksum_compute() of the data to update the 1627 * gang header's blk_cksum as described above. 1628 * 1629 * The two-phase assemble/issue model solves the problem of partial failure -- 1630 * what if you'd freed part of a gang block but then couldn't read the 1631 * gang header for another part? Assembling the entire gang tree first 1632 * ensures that all the necessary gang header I/O has succeeded before 1633 * starting the actual work of free, claim, or write. Once the gang tree 1634 * is assembled, free and claim are in-memory operations that cannot fail. 1635 * 1636 * In the event that a gang write fails, zio_dva_unallocate() walks the 1637 * gang tree to immediately free (i.e. insert back into the space map) 1638 * everything we've allocated. This ensures that we don't get ENOSPC 1639 * errors during repeated suspend/resume cycles due to a flaky device. 1640 * 1641 * Gang rewrites only happen during sync-to-convergence. If we can't assemble 1642 * the gang tree, we won't modify the block, so we can safely defer the free 1643 * (knowing that the block is still intact). If we *can* assemble the gang 1644 * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free 1645 * each constituent bp and we can allocate a new block on the next sync pass. 1646 * 1647 * In all cases, the gang tree allows complete recovery from partial failure. 1648 * ========================================================================== 1649 */ 1650 1651 static zio_t * 1652 zio_read_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data) 1653 { 1654 if (gn != NULL) 1655 return (pio); 1656 1657 return (zio_read(pio, pio->io_spa, bp, data, BP_GET_PSIZE(bp), 1658 NULL, NULL, pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), 1659 &pio->io_bookmark)); 1660 } 1661 1662 zio_t * 1663 zio_rewrite_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data) 1664 { 1665 zio_t *zio; 1666 1667 if (gn != NULL) { 1668 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp, 1669 gn->gn_gbh, SPA_GANGBLOCKSIZE, NULL, NULL, pio->io_priority, 1670 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 1671 /* 1672 * As we rewrite each gang header, the pipeline will compute 1673 * a new gang block header checksum for it; but no one will 1674 * compute a new data checksum, so we do that here. The one 1675 * exception is the gang leader: the pipeline already computed 1676 * its data checksum because that stage precedes gang assembly. 1677 * (Presently, nothing actually uses interior data checksums; 1678 * this is just good hygiene.) 1679 */ 1680 if (gn != pio->io_gang_leader->io_gang_tree) { 1681 zio_checksum_compute(zio, BP_GET_CHECKSUM(bp), 1682 data, BP_GET_PSIZE(bp)); 1683 } 1684 /* 1685 * If we are here to damage data for testing purposes, 1686 * leave the GBH alone so that we can detect the damage. 1687 */ 1688 if (pio->io_gang_leader->io_flags & ZIO_FLAG_INDUCE_DAMAGE) 1689 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES; 1690 } else { 1691 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp, 1692 data, BP_GET_PSIZE(bp), NULL, NULL, pio->io_priority, 1693 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 1694 } 1695 1696 return (zio); 1697 } 1698 1699 /* ARGSUSED */ 1700 zio_t * 1701 zio_free_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data) 1702 { 1703 return (zio_free_sync(pio, pio->io_spa, pio->io_txg, bp, 1704 ZIO_GANG_CHILD_FLAGS(pio))); 1705 } 1706 1707 /* ARGSUSED */ 1708 zio_t * 1709 zio_claim_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data) 1710 { 1711 return (zio_claim(pio, pio->io_spa, pio->io_txg, bp, 1712 NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio))); 1713 } 1714 1715 static zio_gang_issue_func_t *zio_gang_issue_func[ZIO_TYPES] = { 1716 NULL, 1717 zio_read_gang, 1718 zio_rewrite_gang, 1719 zio_free_gang, 1720 zio_claim_gang, 1721 NULL 1722 }; 1723 1724 static void zio_gang_tree_assemble_done(zio_t *zio); 1725 1726 static zio_gang_node_t * 1727 zio_gang_node_alloc(zio_gang_node_t **gnpp) 1728 { 1729 zio_gang_node_t *gn; 1730 1731 ASSERT(*gnpp == NULL); 1732 1733 gn = kmem_zalloc(sizeof (*gn), KM_SLEEP); 1734 gn->gn_gbh = zio_buf_alloc(SPA_GANGBLOCKSIZE); 1735 *gnpp = gn; 1736 1737 return (gn); 1738 } 1739 1740 static void 1741 zio_gang_node_free(zio_gang_node_t **gnpp) 1742 { 1743 zio_gang_node_t *gn = *gnpp; 1744 1745 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) 1746 ASSERT(gn->gn_child[g] == NULL); 1747 1748 zio_buf_free(gn->gn_gbh, SPA_GANGBLOCKSIZE); 1749 kmem_free(gn, sizeof (*gn)); 1750 *gnpp = NULL; 1751 } 1752 1753 static void 1754 zio_gang_tree_free(zio_gang_node_t **gnpp) 1755 { 1756 zio_gang_node_t *gn = *gnpp; 1757 1758 if (gn == NULL) 1759 return; 1760 1761 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) 1762 zio_gang_tree_free(&gn->gn_child[g]); 1763 1764 zio_gang_node_free(gnpp); 1765 } 1766 1767 static void 1768 zio_gang_tree_assemble(zio_t *gio, blkptr_t *bp, zio_gang_node_t **gnpp) 1769 { 1770 zio_gang_node_t *gn = zio_gang_node_alloc(gnpp); 1771 1772 ASSERT(gio->io_gang_leader == gio); 1773 ASSERT(BP_IS_GANG(bp)); 1774 1775 zio_nowait(zio_read(gio, gio->io_spa, bp, gn->gn_gbh, 1776 SPA_GANGBLOCKSIZE, zio_gang_tree_assemble_done, gn, 1777 gio->io_priority, ZIO_GANG_CHILD_FLAGS(gio), &gio->io_bookmark)); 1778 } 1779 1780 static void 1781 zio_gang_tree_assemble_done(zio_t *zio) 1782 { 1783 zio_t *gio = zio->io_gang_leader; 1784 zio_gang_node_t *gn = zio->io_private; 1785 blkptr_t *bp = zio->io_bp; 1786 1787 ASSERT(gio == zio_unique_parent(zio)); 1788 ASSERT(zio->io_child_count == 0); 1789 1790 if (zio->io_error) 1791 return; 1792 1793 if (BP_SHOULD_BYTESWAP(bp)) 1794 byteswap_uint64_array(zio->io_data, zio->io_size); 1795 1796 ASSERT(zio->io_data == gn->gn_gbh); 1797 ASSERT(zio->io_size == SPA_GANGBLOCKSIZE); 1798 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC); 1799 1800 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 1801 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g]; 1802 if (!BP_IS_GANG(gbp)) 1803 continue; 1804 zio_gang_tree_assemble(gio, gbp, &gn->gn_child[g]); 1805 } 1806 } 1807 1808 static void 1809 zio_gang_tree_issue(zio_t *pio, zio_gang_node_t *gn, blkptr_t *bp, void *data) 1810 { 1811 zio_t *gio = pio->io_gang_leader; 1812 zio_t *zio; 1813 1814 ASSERT(BP_IS_GANG(bp) == !!gn); 1815 ASSERT(BP_GET_CHECKSUM(bp) == BP_GET_CHECKSUM(gio->io_bp)); 1816 ASSERT(BP_GET_LSIZE(bp) == BP_GET_PSIZE(bp) || gn == gio->io_gang_tree); 1817 1818 /* 1819 * If you're a gang header, your data is in gn->gn_gbh. 1820 * If you're a gang member, your data is in 'data' and gn == NULL. 1821 */ 1822 zio = zio_gang_issue_func[gio->io_type](pio, bp, gn, data); 1823 1824 if (gn != NULL) { 1825 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC); 1826 1827 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 1828 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g]; 1829 if (BP_IS_HOLE(gbp)) 1830 continue; 1831 zio_gang_tree_issue(zio, gn->gn_child[g], gbp, data); 1832 data = (char *)data + BP_GET_PSIZE(gbp); 1833 } 1834 } 1835 1836 if (gn == gio->io_gang_tree) 1837 ASSERT3P((char *)gio->io_data + gio->io_size, ==, data); 1838 1839 if (zio != pio) 1840 zio_nowait(zio); 1841 } 1842 1843 static int 1844 zio_gang_assemble(zio_t *zio) 1845 { 1846 blkptr_t *bp = zio->io_bp; 1847 1848 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == NULL); 1849 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 1850 1851 zio->io_gang_leader = zio; 1852 1853 zio_gang_tree_assemble(zio, bp, &zio->io_gang_tree); 1854 1855 return (ZIO_PIPELINE_CONTINUE); 1856 } 1857 1858 static int 1859 zio_gang_issue(zio_t *zio) 1860 { 1861 blkptr_t *bp = zio->io_bp; 1862 1863 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE)) 1864 return (ZIO_PIPELINE_STOP); 1865 1866 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == zio); 1867 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 1868 1869 if (zio->io_child_error[ZIO_CHILD_GANG] == 0) 1870 zio_gang_tree_issue(zio, zio->io_gang_tree, bp, zio->io_data); 1871 else 1872 zio_gang_tree_free(&zio->io_gang_tree); 1873 1874 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1875 1876 return (ZIO_PIPELINE_CONTINUE); 1877 } 1878 1879 static void 1880 zio_write_gang_member_ready(zio_t *zio) 1881 { 1882 zio_t *pio = zio_unique_parent(zio); 1883 zio_t *gio = zio->io_gang_leader; 1884 dva_t *cdva = zio->io_bp->blk_dva; 1885 dva_t *pdva = pio->io_bp->blk_dva; 1886 uint64_t asize; 1887 1888 if (BP_IS_HOLE(zio->io_bp)) 1889 return; 1890 1891 ASSERT(BP_IS_HOLE(&zio->io_bp_orig)); 1892 1893 ASSERT(zio->io_child_type == ZIO_CHILD_GANG); 1894 ASSERT3U(zio->io_prop.zp_copies, ==, gio->io_prop.zp_copies); 1895 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(zio->io_bp)); 1896 ASSERT3U(pio->io_prop.zp_copies, <=, BP_GET_NDVAS(pio->io_bp)); 1897 ASSERT3U(BP_GET_NDVAS(zio->io_bp), <=, BP_GET_NDVAS(pio->io_bp)); 1898 1899 mutex_enter(&pio->io_lock); 1900 for (int d = 0; d < BP_GET_NDVAS(zio->io_bp); d++) { 1901 ASSERT(DVA_GET_GANG(&pdva[d])); 1902 asize = DVA_GET_ASIZE(&pdva[d]); 1903 asize += DVA_GET_ASIZE(&cdva[d]); 1904 DVA_SET_ASIZE(&pdva[d], asize); 1905 } 1906 mutex_exit(&pio->io_lock); 1907 } 1908 1909 static int 1910 zio_write_gang_block(zio_t *pio) 1911 { 1912 spa_t *spa = pio->io_spa; 1913 blkptr_t *bp = pio->io_bp; 1914 zio_t *gio = pio->io_gang_leader; 1915 zio_t *zio; 1916 zio_gang_node_t *gn, **gnpp; 1917 zio_gbh_phys_t *gbh; 1918 uint64_t txg = pio->io_txg; 1919 uint64_t resid = pio->io_size; 1920 uint64_t lsize; 1921 int copies = gio->io_prop.zp_copies; 1922 int gbh_copies = MIN(copies + 1, spa_max_replication(spa)); 1923 zio_prop_t zp; 1924 int error; 1925 1926 error = metaslab_alloc(spa, spa_normal_class(spa), SPA_GANGBLOCKSIZE, 1927 bp, gbh_copies, txg, pio == gio ? NULL : gio->io_bp, 1928 METASLAB_HINTBP_FAVOR | METASLAB_GANG_HEADER); 1929 if (error) { 1930 pio->io_error = error; 1931 return (ZIO_PIPELINE_CONTINUE); 1932 } 1933 1934 if (pio == gio) { 1935 gnpp = &gio->io_gang_tree; 1936 } else { 1937 gnpp = pio->io_private; 1938 ASSERT(pio->io_ready == zio_write_gang_member_ready); 1939 } 1940 1941 gn = zio_gang_node_alloc(gnpp); 1942 gbh = gn->gn_gbh; 1943 bzero(gbh, SPA_GANGBLOCKSIZE); 1944 1945 /* 1946 * Create the gang header. 1947 */ 1948 zio = zio_rewrite(pio, spa, txg, bp, gbh, SPA_GANGBLOCKSIZE, NULL, NULL, 1949 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 1950 1951 /* 1952 * Create and nowait the gang children. 1953 */ 1954 for (int g = 0; resid != 0; resid -= lsize, g++) { 1955 lsize = P2ROUNDUP(resid / (SPA_GBH_NBLKPTRS - g), 1956 SPA_MINBLOCKSIZE); 1957 ASSERT(lsize >= SPA_MINBLOCKSIZE && lsize <= resid); 1958 1959 zp.zp_checksum = gio->io_prop.zp_checksum; 1960 zp.zp_compress = ZIO_COMPRESS_OFF; 1961 zp.zp_type = DMU_OT_NONE; 1962 zp.zp_level = 0; 1963 zp.zp_copies = gio->io_prop.zp_copies; 1964 zp.zp_dedup = B_FALSE; 1965 zp.zp_dedup_verify = B_FALSE; 1966 zp.zp_nopwrite = B_FALSE; 1967 1968 zio_nowait(zio_write(zio, spa, txg, &gbh->zg_blkptr[g], 1969 (char *)pio->io_data + (pio->io_size - resid), lsize, &zp, 1970 zio_write_gang_member_ready, NULL, NULL, &gn->gn_child[g], 1971 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), 1972 &pio->io_bookmark)); 1973 } 1974 1975 /* 1976 * Set pio's pipeline to just wait for zio to finish. 1977 */ 1978 pio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1979 1980 zio_nowait(zio); 1981 1982 return (ZIO_PIPELINE_CONTINUE); 1983 } 1984 1985 /* 1986 * The zio_nop_write stage in the pipeline determines if allocating a 1987 * new bp is necessary. The nopwrite feature can handle writes in 1988 * either syncing or open context (i.e. zil writes) and as a result is 1989 * mutually exclusive with dedup. 1990 * 1991 * By leveraging a cryptographically secure checksum, such as SHA256, we 1992 * can compare the checksums of the new data and the old to determine if 1993 * allocating a new block is required. Note that our requirements for 1994 * cryptographic strength are fairly weak: there can't be any accidental 1995 * hash collisions, but we don't need to be secure against intentional 1996 * (malicious) collisions. To trigger a nopwrite, you have to be able 1997 * to write the file to begin with, and triggering an incorrect (hash 1998 * collision) nopwrite is no worse than simply writing to the file. 1999 * That said, there are no known attacks against the checksum algorithms 2000 * used for nopwrite, assuming that the salt and the checksums 2001 * themselves remain secret. 2002 */ 2003 static int 2004 zio_nop_write(zio_t *zio) 2005 { 2006 blkptr_t *bp = zio->io_bp; 2007 blkptr_t *bp_orig = &zio->io_bp_orig; 2008 zio_prop_t *zp = &zio->io_prop; 2009 2010 ASSERT(BP_GET_LEVEL(bp) == 0); 2011 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 2012 ASSERT(zp->zp_nopwrite); 2013 ASSERT(!zp->zp_dedup); 2014 ASSERT(zio->io_bp_override == NULL); 2015 ASSERT(IO_IS_ALLOCATING(zio)); 2016 2017 /* 2018 * Check to see if the original bp and the new bp have matching 2019 * characteristics (i.e. same checksum, compression algorithms, etc). 2020 * If they don't then just continue with the pipeline which will 2021 * allocate a new bp. 2022 */ 2023 if (BP_IS_HOLE(bp_orig) || 2024 !(zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_flags & 2025 ZCHECKSUM_FLAG_NOPWRITE) || 2026 BP_GET_CHECKSUM(bp) != BP_GET_CHECKSUM(bp_orig) || 2027 BP_GET_COMPRESS(bp) != BP_GET_COMPRESS(bp_orig) || 2028 BP_GET_DEDUP(bp) != BP_GET_DEDUP(bp_orig) || 2029 zp->zp_copies != BP_GET_NDVAS(bp_orig)) 2030 return (ZIO_PIPELINE_CONTINUE); 2031 2032 /* 2033 * If the checksums match then reset the pipeline so that we 2034 * avoid allocating a new bp and issuing any I/O. 2035 */ 2036 if (ZIO_CHECKSUM_EQUAL(bp->blk_cksum, bp_orig->blk_cksum)) { 2037 ASSERT(zio_checksum_table[zp->zp_checksum].ci_flags & 2038 ZCHECKSUM_FLAG_NOPWRITE); 2039 ASSERT3U(BP_GET_PSIZE(bp), ==, BP_GET_PSIZE(bp_orig)); 2040 ASSERT3U(BP_GET_LSIZE(bp), ==, BP_GET_LSIZE(bp_orig)); 2041 ASSERT(zp->zp_compress != ZIO_COMPRESS_OFF); 2042 ASSERT(bcmp(&bp->blk_prop, &bp_orig->blk_prop, 2043 sizeof (uint64_t)) == 0); 2044 2045 *bp = *bp_orig; 2046 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 2047 zio->io_flags |= ZIO_FLAG_NOPWRITE; 2048 } 2049 2050 return (ZIO_PIPELINE_CONTINUE); 2051 } 2052 2053 /* 2054 * ========================================================================== 2055 * Dedup 2056 * ========================================================================== 2057 */ 2058 static void 2059 zio_ddt_child_read_done(zio_t *zio) 2060 { 2061 blkptr_t *bp = zio->io_bp; 2062 ddt_entry_t *dde = zio->io_private; 2063 ddt_phys_t *ddp; 2064 zio_t *pio = zio_unique_parent(zio); 2065 2066 mutex_enter(&pio->io_lock); 2067 ddp = ddt_phys_select(dde, bp); 2068 if (zio->io_error == 0) 2069 ddt_phys_clear(ddp); /* this ddp doesn't need repair */ 2070 if (zio->io_error == 0 && dde->dde_repair_data == NULL) 2071 dde->dde_repair_data = zio->io_data; 2072 else 2073 zio_buf_free(zio->io_data, zio->io_size); 2074 mutex_exit(&pio->io_lock); 2075 } 2076 2077 static int 2078 zio_ddt_read_start(zio_t *zio) 2079 { 2080 blkptr_t *bp = zio->io_bp; 2081 2082 ASSERT(BP_GET_DEDUP(bp)); 2083 ASSERT(BP_GET_PSIZE(bp) == zio->io_size); 2084 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2085 2086 if (zio->io_child_error[ZIO_CHILD_DDT]) { 2087 ddt_t *ddt = ddt_select(zio->io_spa, bp); 2088 ddt_entry_t *dde = ddt_repair_start(ddt, bp); 2089 ddt_phys_t *ddp = dde->dde_phys; 2090 ddt_phys_t *ddp_self = ddt_phys_select(dde, bp); 2091 blkptr_t blk; 2092 2093 ASSERT(zio->io_vsd == NULL); 2094 zio->io_vsd = dde; 2095 2096 if (ddp_self == NULL) 2097 return (ZIO_PIPELINE_CONTINUE); 2098 2099 for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) { 2100 if (ddp->ddp_phys_birth == 0 || ddp == ddp_self) 2101 continue; 2102 ddt_bp_create(ddt->ddt_checksum, &dde->dde_key, ddp, 2103 &blk); 2104 zio_nowait(zio_read(zio, zio->io_spa, &blk, 2105 zio_buf_alloc(zio->io_size), zio->io_size, 2106 zio_ddt_child_read_done, dde, zio->io_priority, 2107 ZIO_DDT_CHILD_FLAGS(zio) | ZIO_FLAG_DONT_PROPAGATE, 2108 &zio->io_bookmark)); 2109 } 2110 return (ZIO_PIPELINE_CONTINUE); 2111 } 2112 2113 zio_nowait(zio_read(zio, zio->io_spa, bp, 2114 zio->io_data, zio->io_size, NULL, NULL, zio->io_priority, 2115 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark)); 2116 2117 return (ZIO_PIPELINE_CONTINUE); 2118 } 2119 2120 static int 2121 zio_ddt_read_done(zio_t *zio) 2122 { 2123 blkptr_t *bp = zio->io_bp; 2124 2125 if (zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE)) 2126 return (ZIO_PIPELINE_STOP); 2127 2128 ASSERT(BP_GET_DEDUP(bp)); 2129 ASSERT(BP_GET_PSIZE(bp) == zio->io_size); 2130 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2131 2132 if (zio->io_child_error[ZIO_CHILD_DDT]) { 2133 ddt_t *ddt = ddt_select(zio->io_spa, bp); 2134 ddt_entry_t *dde = zio->io_vsd; 2135 if (ddt == NULL) { 2136 ASSERT(spa_load_state(zio->io_spa) != SPA_LOAD_NONE); 2137 return (ZIO_PIPELINE_CONTINUE); 2138 } 2139 if (dde == NULL) { 2140 zio->io_stage = ZIO_STAGE_DDT_READ_START >> 1; 2141 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE); 2142 return (ZIO_PIPELINE_STOP); 2143 } 2144 if (dde->dde_repair_data != NULL) { 2145 bcopy(dde->dde_repair_data, zio->io_data, zio->io_size); 2146 zio->io_child_error[ZIO_CHILD_DDT] = 0; 2147 } 2148 ddt_repair_done(ddt, dde); 2149 zio->io_vsd = NULL; 2150 } 2151 2152 ASSERT(zio->io_vsd == NULL); 2153 2154 return (ZIO_PIPELINE_CONTINUE); 2155 } 2156 2157 static boolean_t 2158 zio_ddt_collision(zio_t *zio, ddt_t *ddt, ddt_entry_t *dde) 2159 { 2160 spa_t *spa = zio->io_spa; 2161 2162 /* 2163 * Note: we compare the original data, not the transformed data, 2164 * because when zio->io_bp is an override bp, we will not have 2165 * pushed the I/O transforms. That's an important optimization 2166 * because otherwise we'd compress/encrypt all dmu_sync() data twice. 2167 */ 2168 for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) { 2169 zio_t *lio = dde->dde_lead_zio[p]; 2170 2171 if (lio != NULL) { 2172 return (lio->io_orig_size != zio->io_orig_size || 2173 bcmp(zio->io_orig_data, lio->io_orig_data, 2174 zio->io_orig_size) != 0); 2175 } 2176 } 2177 2178 for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) { 2179 ddt_phys_t *ddp = &dde->dde_phys[p]; 2180 2181 if (ddp->ddp_phys_birth != 0) { 2182 arc_buf_t *abuf = NULL; 2183 arc_flags_t aflags = ARC_FLAG_WAIT; 2184 blkptr_t blk = *zio->io_bp; 2185 int error; 2186 2187 ddt_bp_fill(ddp, &blk, ddp->ddp_phys_birth); 2188 2189 ddt_exit(ddt); 2190 2191 error = arc_read(NULL, spa, &blk, 2192 arc_getbuf_func, &abuf, ZIO_PRIORITY_SYNC_READ, 2193 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, 2194 &aflags, &zio->io_bookmark); 2195 2196 if (error == 0) { 2197 if (arc_buf_size(abuf) != zio->io_orig_size || 2198 bcmp(abuf->b_data, zio->io_orig_data, 2199 zio->io_orig_size) != 0) 2200 error = SET_ERROR(EEXIST); 2201 VERIFY(arc_buf_remove_ref(abuf, &abuf)); 2202 } 2203 2204 ddt_enter(ddt); 2205 return (error != 0); 2206 } 2207 } 2208 2209 return (B_FALSE); 2210 } 2211 2212 static void 2213 zio_ddt_child_write_ready(zio_t *zio) 2214 { 2215 int p = zio->io_prop.zp_copies; 2216 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp); 2217 ddt_entry_t *dde = zio->io_private; 2218 ddt_phys_t *ddp = &dde->dde_phys[p]; 2219 zio_t *pio; 2220 2221 if (zio->io_error) 2222 return; 2223 2224 ddt_enter(ddt); 2225 2226 ASSERT(dde->dde_lead_zio[p] == zio); 2227 2228 ddt_phys_fill(ddp, zio->io_bp); 2229 2230 while ((pio = zio_walk_parents(zio)) != NULL) 2231 ddt_bp_fill(ddp, pio->io_bp, zio->io_txg); 2232 2233 ddt_exit(ddt); 2234 } 2235 2236 static void 2237 zio_ddt_child_write_done(zio_t *zio) 2238 { 2239 int p = zio->io_prop.zp_copies; 2240 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp); 2241 ddt_entry_t *dde = zio->io_private; 2242 ddt_phys_t *ddp = &dde->dde_phys[p]; 2243 2244 ddt_enter(ddt); 2245 2246 ASSERT(ddp->ddp_refcnt == 0); 2247 ASSERT(dde->dde_lead_zio[p] == zio); 2248 dde->dde_lead_zio[p] = NULL; 2249 2250 if (zio->io_error == 0) { 2251 while (zio_walk_parents(zio) != NULL) 2252 ddt_phys_addref(ddp); 2253 } else { 2254 ddt_phys_clear(ddp); 2255 } 2256 2257 ddt_exit(ddt); 2258 } 2259 2260 static void 2261 zio_ddt_ditto_write_done(zio_t *zio) 2262 { 2263 int p = DDT_PHYS_DITTO; 2264 zio_prop_t *zp = &zio->io_prop; 2265 blkptr_t *bp = zio->io_bp; 2266 ddt_t *ddt = ddt_select(zio->io_spa, bp); 2267 ddt_entry_t *dde = zio->io_private; 2268 ddt_phys_t *ddp = &dde->dde_phys[p]; 2269 ddt_key_t *ddk = &dde->dde_key; 2270 2271 ddt_enter(ddt); 2272 2273 ASSERT(ddp->ddp_refcnt == 0); 2274 ASSERT(dde->dde_lead_zio[p] == zio); 2275 dde->dde_lead_zio[p] = NULL; 2276 2277 if (zio->io_error == 0) { 2278 ASSERT(ZIO_CHECKSUM_EQUAL(bp->blk_cksum, ddk->ddk_cksum)); 2279 ASSERT(zp->zp_copies < SPA_DVAS_PER_BP); 2280 ASSERT(zp->zp_copies == BP_GET_NDVAS(bp) - BP_IS_GANG(bp)); 2281 if (ddp->ddp_phys_birth != 0) 2282 ddt_phys_free(ddt, ddk, ddp, zio->io_txg); 2283 ddt_phys_fill(ddp, bp); 2284 } 2285 2286 ddt_exit(ddt); 2287 } 2288 2289 static int 2290 zio_ddt_write(zio_t *zio) 2291 { 2292 spa_t *spa = zio->io_spa; 2293 blkptr_t *bp = zio->io_bp; 2294 uint64_t txg = zio->io_txg; 2295 zio_prop_t *zp = &zio->io_prop; 2296 int p = zp->zp_copies; 2297 int ditto_copies; 2298 zio_t *cio = NULL; 2299 zio_t *dio = NULL; 2300 ddt_t *ddt = ddt_select(spa, bp); 2301 ddt_entry_t *dde; 2302 ddt_phys_t *ddp; 2303 2304 ASSERT(BP_GET_DEDUP(bp)); 2305 ASSERT(BP_GET_CHECKSUM(bp) == zp->zp_checksum); 2306 ASSERT(BP_IS_HOLE(bp) || zio->io_bp_override); 2307 2308 ddt_enter(ddt); 2309 dde = ddt_lookup(ddt, bp, B_TRUE); 2310 ddp = &dde->dde_phys[p]; 2311 2312 if (zp->zp_dedup_verify && zio_ddt_collision(zio, ddt, dde)) { 2313 /* 2314 * If we're using a weak checksum, upgrade to a strong checksum 2315 * and try again. If we're already using a strong checksum, 2316 * we can't resolve it, so just convert to an ordinary write. 2317 * (And automatically e-mail a paper to Nature?) 2318 */ 2319 if (!(zio_checksum_table[zp->zp_checksum].ci_flags & 2320 ZCHECKSUM_FLAG_DEDUP)) { 2321 zp->zp_checksum = spa_dedup_checksum(spa); 2322 zio_pop_transforms(zio); 2323 zio->io_stage = ZIO_STAGE_OPEN; 2324 BP_ZERO(bp); 2325 } else { 2326 zp->zp_dedup = B_FALSE; 2327 } 2328 zio->io_pipeline = ZIO_WRITE_PIPELINE; 2329 ddt_exit(ddt); 2330 return (ZIO_PIPELINE_CONTINUE); 2331 } 2332 2333 ditto_copies = ddt_ditto_copies_needed(ddt, dde, ddp); 2334 ASSERT(ditto_copies < SPA_DVAS_PER_BP); 2335 2336 if (ditto_copies > ddt_ditto_copies_present(dde) && 2337 dde->dde_lead_zio[DDT_PHYS_DITTO] == NULL) { 2338 zio_prop_t czp = *zp; 2339 2340 czp.zp_copies = ditto_copies; 2341 2342 /* 2343 * If we arrived here with an override bp, we won't have run 2344 * the transform stack, so we won't have the data we need to 2345 * generate a child i/o. So, toss the override bp and restart. 2346 * This is safe, because using the override bp is just an 2347 * optimization; and it's rare, so the cost doesn't matter. 2348 */ 2349 if (zio->io_bp_override) { 2350 zio_pop_transforms(zio); 2351 zio->io_stage = ZIO_STAGE_OPEN; 2352 zio->io_pipeline = ZIO_WRITE_PIPELINE; 2353 zio->io_bp_override = NULL; 2354 BP_ZERO(bp); 2355 ddt_exit(ddt); 2356 return (ZIO_PIPELINE_CONTINUE); 2357 } 2358 2359 dio = zio_write(zio, spa, txg, bp, zio->io_orig_data, 2360 zio->io_orig_size, &czp, NULL, NULL, 2361 zio_ddt_ditto_write_done, dde, zio->io_priority, 2362 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark); 2363 2364 zio_push_transform(dio, zio->io_data, zio->io_size, 0, NULL); 2365 dde->dde_lead_zio[DDT_PHYS_DITTO] = dio; 2366 } 2367 2368 if (ddp->ddp_phys_birth != 0 || dde->dde_lead_zio[p] != NULL) { 2369 if (ddp->ddp_phys_birth != 0) 2370 ddt_bp_fill(ddp, bp, txg); 2371 if (dde->dde_lead_zio[p] != NULL) 2372 zio_add_child(zio, dde->dde_lead_zio[p]); 2373 else 2374 ddt_phys_addref(ddp); 2375 } else if (zio->io_bp_override) { 2376 ASSERT(bp->blk_birth == txg); 2377 ASSERT(BP_EQUAL(bp, zio->io_bp_override)); 2378 ddt_phys_fill(ddp, bp); 2379 ddt_phys_addref(ddp); 2380 } else { 2381 cio = zio_write(zio, spa, txg, bp, zio->io_orig_data, 2382 zio->io_orig_size, zp, zio_ddt_child_write_ready, NULL, 2383 zio_ddt_child_write_done, dde, zio->io_priority, 2384 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark); 2385 2386 zio_push_transform(cio, zio->io_data, zio->io_size, 0, NULL); 2387 dde->dde_lead_zio[p] = cio; 2388 } 2389 2390 ddt_exit(ddt); 2391 2392 if (cio) 2393 zio_nowait(cio); 2394 if (dio) 2395 zio_nowait(dio); 2396 2397 return (ZIO_PIPELINE_CONTINUE); 2398 } 2399 2400 ddt_entry_t *freedde; /* for debugging */ 2401 2402 static int 2403 zio_ddt_free(zio_t *zio) 2404 { 2405 spa_t *spa = zio->io_spa; 2406 blkptr_t *bp = zio->io_bp; 2407 ddt_t *ddt = ddt_select(spa, bp); 2408 ddt_entry_t *dde; 2409 ddt_phys_t *ddp; 2410 2411 ASSERT(BP_GET_DEDUP(bp)); 2412 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2413 2414 ddt_enter(ddt); 2415 freedde = dde = ddt_lookup(ddt, bp, B_TRUE); 2416 ddp = ddt_phys_select(dde, bp); 2417 ddt_phys_decref(ddp); 2418 ddt_exit(ddt); 2419 2420 return (ZIO_PIPELINE_CONTINUE); 2421 } 2422 2423 /* 2424 * ========================================================================== 2425 * Allocate and free blocks 2426 * ========================================================================== 2427 */ 2428 static int 2429 zio_dva_allocate(zio_t *zio) 2430 { 2431 spa_t *spa = zio->io_spa; 2432 metaslab_class_t *mc = spa_normal_class(spa); 2433 blkptr_t *bp = zio->io_bp; 2434 int error; 2435 int flags = 0; 2436 2437 if (zio->io_gang_leader == NULL) { 2438 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 2439 zio->io_gang_leader = zio; 2440 } 2441 2442 ASSERT(BP_IS_HOLE(bp)); 2443 ASSERT0(BP_GET_NDVAS(bp)); 2444 ASSERT3U(zio->io_prop.zp_copies, >, 0); 2445 ASSERT3U(zio->io_prop.zp_copies, <=, spa_max_replication(spa)); 2446 ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp)); 2447 2448 /* 2449 * The dump device does not support gang blocks so allocation on 2450 * behalf of the dump device (i.e. ZIO_FLAG_NODATA) must avoid 2451 * the "fast" gang feature. 2452 */ 2453 flags |= (zio->io_flags & ZIO_FLAG_NODATA) ? METASLAB_GANG_AVOID : 0; 2454 flags |= (zio->io_flags & ZIO_FLAG_GANG_CHILD) ? 2455 METASLAB_GANG_CHILD : 0; 2456 error = metaslab_alloc(spa, mc, zio->io_size, bp, 2457 zio->io_prop.zp_copies, zio->io_txg, NULL, flags); 2458 2459 if (error) { 2460 spa_dbgmsg(spa, "%s: metaslab allocation failure: zio %p, " 2461 "size %llu, error %d", spa_name(spa), zio, zio->io_size, 2462 error); 2463 if (error == ENOSPC && zio->io_size > SPA_MINBLOCKSIZE) 2464 return (zio_write_gang_block(zio)); 2465 zio->io_error = error; 2466 } 2467 2468 return (ZIO_PIPELINE_CONTINUE); 2469 } 2470 2471 static int 2472 zio_dva_free(zio_t *zio) 2473 { 2474 metaslab_free(zio->io_spa, zio->io_bp, zio->io_txg, B_FALSE); 2475 2476 return (ZIO_PIPELINE_CONTINUE); 2477 } 2478 2479 static int 2480 zio_dva_claim(zio_t *zio) 2481 { 2482 int error; 2483 2484 error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg); 2485 if (error) 2486 zio->io_error = error; 2487 2488 return (ZIO_PIPELINE_CONTINUE); 2489 } 2490 2491 /* 2492 * Undo an allocation. This is used by zio_done() when an I/O fails 2493 * and we want to give back the block we just allocated. 2494 * This handles both normal blocks and gang blocks. 2495 */ 2496 static void 2497 zio_dva_unallocate(zio_t *zio, zio_gang_node_t *gn, blkptr_t *bp) 2498 { 2499 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp)); 2500 ASSERT(zio->io_bp_override == NULL); 2501 2502 if (!BP_IS_HOLE(bp)) 2503 metaslab_free(zio->io_spa, bp, bp->blk_birth, B_TRUE); 2504 2505 if (gn != NULL) { 2506 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 2507 zio_dva_unallocate(zio, gn->gn_child[g], 2508 &gn->gn_gbh->zg_blkptr[g]); 2509 } 2510 } 2511 } 2512 2513 /* 2514 * Try to allocate an intent log block. Return 0 on success, errno on failure. 2515 */ 2516 int 2517 zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp, blkptr_t *old_bp, 2518 uint64_t size, boolean_t use_slog) 2519 { 2520 int error = 1; 2521 2522 ASSERT(txg > spa_syncing_txg(spa)); 2523 2524 /* 2525 * ZIL blocks are always contiguous (i.e. not gang blocks) so we 2526 * set the METASLAB_GANG_AVOID flag so that they don't "fast gang" 2527 * when allocating them. 2528 */ 2529 if (use_slog) { 2530 error = metaslab_alloc(spa, spa_log_class(spa), size, 2531 new_bp, 1, txg, old_bp, 2532 METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID); 2533 } 2534 2535 if (error) { 2536 error = metaslab_alloc(spa, spa_normal_class(spa), size, 2537 new_bp, 1, txg, old_bp, 2538 METASLAB_HINTBP_AVOID); 2539 } 2540 2541 if (error == 0) { 2542 BP_SET_LSIZE(new_bp, size); 2543 BP_SET_PSIZE(new_bp, size); 2544 BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF); 2545 BP_SET_CHECKSUM(new_bp, 2546 spa_version(spa) >= SPA_VERSION_SLIM_ZIL 2547 ? ZIO_CHECKSUM_ZILOG2 : ZIO_CHECKSUM_ZILOG); 2548 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG); 2549 BP_SET_LEVEL(new_bp, 0); 2550 BP_SET_DEDUP(new_bp, 0); 2551 BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER); 2552 } 2553 2554 return (error); 2555 } 2556 2557 /* 2558 * Free an intent log block. 2559 */ 2560 void 2561 zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp) 2562 { 2563 ASSERT(BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG); 2564 ASSERT(!BP_IS_GANG(bp)); 2565 2566 zio_free(spa, txg, bp); 2567 } 2568 2569 /* 2570 * ========================================================================== 2571 * Read and write to physical devices 2572 * ========================================================================== 2573 */ 2574 2575 2576 /* 2577 * Issue an I/O to the underlying vdev. Typically the issue pipeline 2578 * stops after this stage and will resume upon I/O completion. 2579 * However, there are instances where the vdev layer may need to 2580 * continue the pipeline when an I/O was not issued. Since the I/O 2581 * that was sent to the vdev layer might be different than the one 2582 * currently active in the pipeline (see vdev_queue_io()), we explicitly 2583 * force the underlying vdev layers to call either zio_execute() or 2584 * zio_interrupt() to ensure that the pipeline continues with the correct I/O. 2585 */ 2586 static int 2587 zio_vdev_io_start(zio_t *zio) 2588 { 2589 vdev_t *vd = zio->io_vd; 2590 uint64_t align; 2591 spa_t *spa = zio->io_spa; 2592 2593 ASSERT(zio->io_error == 0); 2594 ASSERT(zio->io_child_error[ZIO_CHILD_VDEV] == 0); 2595 2596 if (vd == NULL) { 2597 if (!(zio->io_flags & ZIO_FLAG_CONFIG_WRITER)) 2598 spa_config_enter(spa, SCL_ZIO, zio, RW_READER); 2599 2600 /* 2601 * The mirror_ops handle multiple DVAs in a single BP. 2602 */ 2603 vdev_mirror_ops.vdev_op_io_start(zio); 2604 return (ZIO_PIPELINE_STOP); 2605 } 2606 2607 /* 2608 * We keep track of time-sensitive I/Os so that the scan thread 2609 * can quickly react to certain workloads. In particular, we care 2610 * about non-scrubbing, top-level reads and writes with the following 2611 * characteristics: 2612 * - synchronous writes of user data to non-slog devices 2613 * - any reads of user data 2614 * When these conditions are met, adjust the timestamp of spa_last_io 2615 * which allows the scan thread to adjust its workload accordingly. 2616 */ 2617 if (!(zio->io_flags & ZIO_FLAG_SCAN_THREAD) && zio->io_bp != NULL && 2618 vd == vd->vdev_top && !vd->vdev_islog && 2619 zio->io_bookmark.zb_objset != DMU_META_OBJSET && 2620 zio->io_txg != spa_syncing_txg(spa)) { 2621 uint64_t old = spa->spa_last_io; 2622 uint64_t new = ddi_get_lbolt64(); 2623 if (old != new) 2624 (void) atomic_cas_64(&spa->spa_last_io, old, new); 2625 } 2626 2627 align = 1ULL << vd->vdev_top->vdev_ashift; 2628 2629 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL) && 2630 P2PHASE(zio->io_size, align) != 0) { 2631 /* Transform logical writes to be a full physical block size. */ 2632 uint64_t asize = P2ROUNDUP(zio->io_size, align); 2633 char *abuf = zio_buf_alloc(asize); 2634 ASSERT(vd == vd->vdev_top); 2635 if (zio->io_type == ZIO_TYPE_WRITE) { 2636 bcopy(zio->io_data, abuf, zio->io_size); 2637 bzero(abuf + zio->io_size, asize - zio->io_size); 2638 } 2639 zio_push_transform(zio, abuf, asize, asize, zio_subblock); 2640 } 2641 2642 /* 2643 * If this is not a physical io, make sure that it is properly aligned 2644 * before proceeding. 2645 */ 2646 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL)) { 2647 ASSERT0(P2PHASE(zio->io_offset, align)); 2648 ASSERT0(P2PHASE(zio->io_size, align)); 2649 } else { 2650 /* 2651 * For physical writes, we allow 512b aligned writes and assume 2652 * the device will perform a read-modify-write as necessary. 2653 */ 2654 ASSERT0(P2PHASE(zio->io_offset, SPA_MINBLOCKSIZE)); 2655 ASSERT0(P2PHASE(zio->io_size, SPA_MINBLOCKSIZE)); 2656 } 2657 2658 VERIFY(zio->io_type != ZIO_TYPE_WRITE || spa_writeable(spa)); 2659 2660 /* 2661 * If this is a repair I/O, and there's no self-healing involved -- 2662 * that is, we're just resilvering what we expect to resilver -- 2663 * then don't do the I/O unless zio's txg is actually in vd's DTL. 2664 * This prevents spurious resilvering with nested replication. 2665 * For example, given a mirror of mirrors, (A+B)+(C+D), if only 2666 * A is out of date, we'll read from C+D, then use the data to 2667 * resilver A+B -- but we don't actually want to resilver B, just A. 2668 * The top-level mirror has no way to know this, so instead we just 2669 * discard unnecessary repairs as we work our way down the vdev tree. 2670 * The same logic applies to any form of nested replication: 2671 * ditto + mirror, RAID-Z + replacing, etc. This covers them all. 2672 */ 2673 if ((zio->io_flags & ZIO_FLAG_IO_REPAIR) && 2674 !(zio->io_flags & ZIO_FLAG_SELF_HEAL) && 2675 zio->io_txg != 0 && /* not a delegated i/o */ 2676 !vdev_dtl_contains(vd, DTL_PARTIAL, zio->io_txg, 1)) { 2677 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 2678 zio_vdev_io_bypass(zio); 2679 return (ZIO_PIPELINE_CONTINUE); 2680 } 2681 2682 if (vd->vdev_ops->vdev_op_leaf && 2683 (zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE)) { 2684 2685 if (zio->io_type == ZIO_TYPE_READ && vdev_cache_read(zio)) 2686 return (ZIO_PIPELINE_CONTINUE); 2687 2688 if ((zio = vdev_queue_io(zio)) == NULL) 2689 return (ZIO_PIPELINE_STOP); 2690 2691 if (!vdev_accessible(vd, zio)) { 2692 zio->io_error = SET_ERROR(ENXIO); 2693 zio_interrupt(zio); 2694 return (ZIO_PIPELINE_STOP); 2695 } 2696 } 2697 2698 vd->vdev_ops->vdev_op_io_start(zio); 2699 return (ZIO_PIPELINE_STOP); 2700 } 2701 2702 static int 2703 zio_vdev_io_done(zio_t *zio) 2704 { 2705 vdev_t *vd = zio->io_vd; 2706 vdev_ops_t *ops = vd ? vd->vdev_ops : &vdev_mirror_ops; 2707 boolean_t unexpected_error = B_FALSE; 2708 2709 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE)) 2710 return (ZIO_PIPELINE_STOP); 2711 2712 ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE); 2713 2714 if (vd != NULL && vd->vdev_ops->vdev_op_leaf) { 2715 2716 vdev_queue_io_done(zio); 2717 2718 if (zio->io_type == ZIO_TYPE_WRITE) 2719 vdev_cache_write(zio); 2720 2721 if (zio_injection_enabled && zio->io_error == 0) 2722 zio->io_error = zio_handle_device_injection(vd, 2723 zio, EIO); 2724 2725 if (zio_injection_enabled && zio->io_error == 0) 2726 zio->io_error = zio_handle_label_injection(zio, EIO); 2727 2728 if (zio->io_error) { 2729 if (!vdev_accessible(vd, zio)) { 2730 zio->io_error = SET_ERROR(ENXIO); 2731 } else { 2732 unexpected_error = B_TRUE; 2733 } 2734 } 2735 } 2736 2737 ops->vdev_op_io_done(zio); 2738 2739 if (unexpected_error) 2740 VERIFY(vdev_probe(vd, zio) == NULL); 2741 2742 return (ZIO_PIPELINE_CONTINUE); 2743 } 2744 2745 /* 2746 * For non-raidz ZIOs, we can just copy aside the bad data read from the 2747 * disk, and use that to finish the checksum ereport later. 2748 */ 2749 static void 2750 zio_vsd_default_cksum_finish(zio_cksum_report_t *zcr, 2751 const void *good_buf) 2752 { 2753 /* no processing needed */ 2754 zfs_ereport_finish_checksum(zcr, good_buf, zcr->zcr_cbdata, B_FALSE); 2755 } 2756 2757 /*ARGSUSED*/ 2758 void 2759 zio_vsd_default_cksum_report(zio_t *zio, zio_cksum_report_t *zcr, void *ignored) 2760 { 2761 void *buf = zio_buf_alloc(zio->io_size); 2762 2763 bcopy(zio->io_data, buf, zio->io_size); 2764 2765 zcr->zcr_cbinfo = zio->io_size; 2766 zcr->zcr_cbdata = buf; 2767 zcr->zcr_finish = zio_vsd_default_cksum_finish; 2768 zcr->zcr_free = zio_buf_free; 2769 } 2770 2771 static int 2772 zio_vdev_io_assess(zio_t *zio) 2773 { 2774 vdev_t *vd = zio->io_vd; 2775 2776 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE)) 2777 return (ZIO_PIPELINE_STOP); 2778 2779 if (vd == NULL && !(zio->io_flags & ZIO_FLAG_CONFIG_WRITER)) 2780 spa_config_exit(zio->io_spa, SCL_ZIO, zio); 2781 2782 if (zio->io_vsd != NULL) { 2783 zio->io_vsd_ops->vsd_free(zio); 2784 zio->io_vsd = NULL; 2785 } 2786 2787 if (zio_injection_enabled && zio->io_error == 0) 2788 zio->io_error = zio_handle_fault_injection(zio, EIO); 2789 2790 /* 2791 * If the I/O failed, determine whether we should attempt to retry it. 2792 * 2793 * On retry, we cut in line in the issue queue, since we don't want 2794 * compression/checksumming/etc. work to prevent our (cheap) IO reissue. 2795 */ 2796 if (zio->io_error && vd == NULL && 2797 !(zio->io_flags & (ZIO_FLAG_DONT_RETRY | ZIO_FLAG_IO_RETRY))) { 2798 ASSERT(!(zio->io_flags & ZIO_FLAG_DONT_QUEUE)); /* not a leaf */ 2799 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_BYPASS)); /* not a leaf */ 2800 zio->io_error = 0; 2801 zio->io_flags |= ZIO_FLAG_IO_RETRY | 2802 ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_AGGREGATE; 2803 zio->io_stage = ZIO_STAGE_VDEV_IO_START >> 1; 2804 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, 2805 zio_requeue_io_start_cut_in_line); 2806 return (ZIO_PIPELINE_STOP); 2807 } 2808 2809 /* 2810 * If we got an error on a leaf device, convert it to ENXIO 2811 * if the device is not accessible at all. 2812 */ 2813 if (zio->io_error && vd != NULL && vd->vdev_ops->vdev_op_leaf && 2814 !vdev_accessible(vd, zio)) 2815 zio->io_error = SET_ERROR(ENXIO); 2816 2817 /* 2818 * If we can't write to an interior vdev (mirror or RAID-Z), 2819 * set vdev_cant_write so that we stop trying to allocate from it. 2820 */ 2821 if (zio->io_error == ENXIO && zio->io_type == ZIO_TYPE_WRITE && 2822 vd != NULL && !vd->vdev_ops->vdev_op_leaf) { 2823 vd->vdev_cant_write = B_TRUE; 2824 } 2825 2826 if (zio->io_error) 2827 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 2828 2829 if (vd != NULL && vd->vdev_ops->vdev_op_leaf && 2830 zio->io_physdone != NULL) { 2831 ASSERT(!(zio->io_flags & ZIO_FLAG_DELEGATED)); 2832 ASSERT(zio->io_child_type == ZIO_CHILD_VDEV); 2833 zio->io_physdone(zio->io_logical); 2834 } 2835 2836 return (ZIO_PIPELINE_CONTINUE); 2837 } 2838 2839 void 2840 zio_vdev_io_reissue(zio_t *zio) 2841 { 2842 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START); 2843 ASSERT(zio->io_error == 0); 2844 2845 zio->io_stage >>= 1; 2846 } 2847 2848 void 2849 zio_vdev_io_redone(zio_t *zio) 2850 { 2851 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_DONE); 2852 2853 zio->io_stage >>= 1; 2854 } 2855 2856 void 2857 zio_vdev_io_bypass(zio_t *zio) 2858 { 2859 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START); 2860 ASSERT(zio->io_error == 0); 2861 2862 zio->io_flags |= ZIO_FLAG_IO_BYPASS; 2863 zio->io_stage = ZIO_STAGE_VDEV_IO_ASSESS >> 1; 2864 } 2865 2866 /* 2867 * ========================================================================== 2868 * Generate and verify checksums 2869 * ========================================================================== 2870 */ 2871 static int 2872 zio_checksum_generate(zio_t *zio) 2873 { 2874 blkptr_t *bp = zio->io_bp; 2875 enum zio_checksum checksum; 2876 2877 if (bp == NULL) { 2878 /* 2879 * This is zio_write_phys(). 2880 * We're either generating a label checksum, or none at all. 2881 */ 2882 checksum = zio->io_prop.zp_checksum; 2883 2884 if (checksum == ZIO_CHECKSUM_OFF) 2885 return (ZIO_PIPELINE_CONTINUE); 2886 2887 ASSERT(checksum == ZIO_CHECKSUM_LABEL); 2888 } else { 2889 if (BP_IS_GANG(bp) && zio->io_child_type == ZIO_CHILD_GANG) { 2890 ASSERT(!IO_IS_ALLOCATING(zio)); 2891 checksum = ZIO_CHECKSUM_GANG_HEADER; 2892 } else { 2893 checksum = BP_GET_CHECKSUM(bp); 2894 } 2895 } 2896 2897 zio_checksum_compute(zio, checksum, zio->io_data, zio->io_size); 2898 2899 return (ZIO_PIPELINE_CONTINUE); 2900 } 2901 2902 static int 2903 zio_checksum_verify(zio_t *zio) 2904 { 2905 zio_bad_cksum_t info; 2906 blkptr_t *bp = zio->io_bp; 2907 int error; 2908 2909 ASSERT(zio->io_vd != NULL); 2910 2911 if (bp == NULL) { 2912 /* 2913 * This is zio_read_phys(). 2914 * We're either verifying a label checksum, or nothing at all. 2915 */ 2916 if (zio->io_prop.zp_checksum == ZIO_CHECKSUM_OFF) 2917 return (ZIO_PIPELINE_CONTINUE); 2918 2919 ASSERT(zio->io_prop.zp_checksum == ZIO_CHECKSUM_LABEL); 2920 } 2921 2922 if ((error = zio_checksum_error(zio, &info)) != 0) { 2923 zio->io_error = error; 2924 if (error == ECKSUM && 2925 !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) { 2926 zfs_ereport_start_checksum(zio->io_spa, 2927 zio->io_vd, zio, zio->io_offset, 2928 zio->io_size, NULL, &info); 2929 } 2930 } 2931 2932 return (ZIO_PIPELINE_CONTINUE); 2933 } 2934 2935 /* 2936 * Called by RAID-Z to ensure we don't compute the checksum twice. 2937 */ 2938 void 2939 zio_checksum_verified(zio_t *zio) 2940 { 2941 zio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY; 2942 } 2943 2944 /* 2945 * ========================================================================== 2946 * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other. 2947 * An error of 0 indicates success. ENXIO indicates whole-device failure, 2948 * which may be transient (e.g. unplugged) or permament. ECKSUM and EIO 2949 * indicate errors that are specific to one I/O, and most likely permanent. 2950 * Any other error is presumed to be worse because we weren't expecting it. 2951 * ========================================================================== 2952 */ 2953 int 2954 zio_worst_error(int e1, int e2) 2955 { 2956 static int zio_error_rank[] = { 0, ENXIO, ECKSUM, EIO }; 2957 int r1, r2; 2958 2959 for (r1 = 0; r1 < sizeof (zio_error_rank) / sizeof (int); r1++) 2960 if (e1 == zio_error_rank[r1]) 2961 break; 2962 2963 for (r2 = 0; r2 < sizeof (zio_error_rank) / sizeof (int); r2++) 2964 if (e2 == zio_error_rank[r2]) 2965 break; 2966 2967 return (r1 > r2 ? e1 : e2); 2968 } 2969 2970 /* 2971 * ========================================================================== 2972 * I/O completion 2973 * ========================================================================== 2974 */ 2975 static int 2976 zio_ready(zio_t *zio) 2977 { 2978 blkptr_t *bp = zio->io_bp; 2979 zio_t *pio, *pio_next; 2980 2981 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) || 2982 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_READY)) 2983 return (ZIO_PIPELINE_STOP); 2984 2985 if (zio->io_ready) { 2986 ASSERT(IO_IS_ALLOCATING(zio)); 2987 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp) || 2988 (zio->io_flags & ZIO_FLAG_NOPWRITE)); 2989 ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0); 2990 2991 zio->io_ready(zio); 2992 } 2993 2994 if (bp != NULL && bp != &zio->io_bp_copy) 2995 zio->io_bp_copy = *bp; 2996 2997 if (zio->io_error) 2998 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 2999 3000 mutex_enter(&zio->io_lock); 3001 zio->io_state[ZIO_WAIT_READY] = 1; 3002 pio = zio_walk_parents(zio); 3003 mutex_exit(&zio->io_lock); 3004 3005 /* 3006 * As we notify zio's parents, new parents could be added. 3007 * New parents go to the head of zio's io_parent_list, however, 3008 * so we will (correctly) not notify them. The remainder of zio's 3009 * io_parent_list, from 'pio_next' onward, cannot change because 3010 * all parents must wait for us to be done before they can be done. 3011 */ 3012 for (; pio != NULL; pio = pio_next) { 3013 pio_next = zio_walk_parents(zio); 3014 zio_notify_parent(pio, zio, ZIO_WAIT_READY); 3015 } 3016 3017 if (zio->io_flags & ZIO_FLAG_NODATA) { 3018 if (BP_IS_GANG(bp)) { 3019 zio->io_flags &= ~ZIO_FLAG_NODATA; 3020 } else { 3021 ASSERT((uintptr_t)zio->io_data < SPA_MAXBLOCKSIZE); 3022 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES; 3023 } 3024 } 3025 3026 if (zio_injection_enabled && 3027 zio->io_spa->spa_syncing_txg == zio->io_txg) 3028 zio_handle_ignored_writes(zio); 3029 3030 return (ZIO_PIPELINE_CONTINUE); 3031 } 3032 3033 static int 3034 zio_done(zio_t *zio) 3035 { 3036 spa_t *spa = zio->io_spa; 3037 zio_t *lio = zio->io_logical; 3038 blkptr_t *bp = zio->io_bp; 3039 vdev_t *vd = zio->io_vd; 3040 uint64_t psize = zio->io_size; 3041 zio_t *pio, *pio_next; 3042 3043 /* 3044 * If our children haven't all completed, 3045 * wait for them and then repeat this pipeline stage. 3046 */ 3047 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE) || 3048 zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE) || 3049 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE) || 3050 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_DONE)) 3051 return (ZIO_PIPELINE_STOP); 3052 3053 for (int c = 0; c < ZIO_CHILD_TYPES; c++) 3054 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 3055 ASSERT(zio->io_children[c][w] == 0); 3056 3057 if (bp != NULL && !BP_IS_EMBEDDED(bp)) { 3058 ASSERT(bp->blk_pad[0] == 0); 3059 ASSERT(bp->blk_pad[1] == 0); 3060 ASSERT(bcmp(bp, &zio->io_bp_copy, sizeof (blkptr_t)) == 0 || 3061 (bp == zio_unique_parent(zio)->io_bp)); 3062 if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(bp) && 3063 zio->io_bp_override == NULL && 3064 !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) { 3065 ASSERT(!BP_SHOULD_BYTESWAP(bp)); 3066 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(bp)); 3067 ASSERT(BP_COUNT_GANG(bp) == 0 || 3068 (BP_COUNT_GANG(bp) == BP_GET_NDVAS(bp))); 3069 } 3070 if (zio->io_flags & ZIO_FLAG_NOPWRITE) 3071 VERIFY(BP_EQUAL(bp, &zio->io_bp_orig)); 3072 } 3073 3074 /* 3075 * If there were child vdev/gang/ddt errors, they apply to us now. 3076 */ 3077 zio_inherit_child_errors(zio, ZIO_CHILD_VDEV); 3078 zio_inherit_child_errors(zio, ZIO_CHILD_GANG); 3079 zio_inherit_child_errors(zio, ZIO_CHILD_DDT); 3080 3081 /* 3082 * If the I/O on the transformed data was successful, generate any 3083 * checksum reports now while we still have the transformed data. 3084 */ 3085 if (zio->io_error == 0) { 3086 while (zio->io_cksum_report != NULL) { 3087 zio_cksum_report_t *zcr = zio->io_cksum_report; 3088 uint64_t align = zcr->zcr_align; 3089 uint64_t asize = P2ROUNDUP(psize, align); 3090 char *abuf = zio->io_data; 3091 3092 if (asize != psize) { 3093 abuf = zio_buf_alloc(asize); 3094 bcopy(zio->io_data, abuf, psize); 3095 bzero(abuf + psize, asize - psize); 3096 } 3097 3098 zio->io_cksum_report = zcr->zcr_next; 3099 zcr->zcr_next = NULL; 3100 zcr->zcr_finish(zcr, abuf); 3101 zfs_ereport_free_checksum(zcr); 3102 3103 if (asize != psize) 3104 zio_buf_free(abuf, asize); 3105 } 3106 } 3107 3108 zio_pop_transforms(zio); /* note: may set zio->io_error */ 3109 3110 vdev_stat_update(zio, psize); 3111 3112 if (zio->io_error) { 3113 /* 3114 * If this I/O is attached to a particular vdev, 3115 * generate an error message describing the I/O failure 3116 * at the block level. We ignore these errors if the 3117 * device is currently unavailable. 3118 */ 3119 if (zio->io_error != ECKSUM && vd != NULL && !vdev_is_dead(vd)) 3120 zfs_ereport_post(FM_EREPORT_ZFS_IO, spa, vd, zio, 0, 0); 3121 3122 if ((zio->io_error == EIO || !(zio->io_flags & 3123 (ZIO_FLAG_SPECULATIVE | ZIO_FLAG_DONT_PROPAGATE))) && 3124 zio == lio) { 3125 /* 3126 * For logical I/O requests, tell the SPA to log the 3127 * error and generate a logical data ereport. 3128 */ 3129 spa_log_error(spa, zio); 3130 zfs_ereport_post(FM_EREPORT_ZFS_DATA, spa, NULL, zio, 3131 0, 0); 3132 } 3133 } 3134 3135 if (zio->io_error && zio == lio) { 3136 /* 3137 * Determine whether zio should be reexecuted. This will 3138 * propagate all the way to the root via zio_notify_parent(). 3139 */ 3140 ASSERT(vd == NULL && bp != NULL); 3141 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 3142 3143 if (IO_IS_ALLOCATING(zio) && 3144 !(zio->io_flags & ZIO_FLAG_CANFAIL)) { 3145 if (zio->io_error != ENOSPC) 3146 zio->io_reexecute |= ZIO_REEXECUTE_NOW; 3147 else 3148 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 3149 } 3150 3151 if ((zio->io_type == ZIO_TYPE_READ || 3152 zio->io_type == ZIO_TYPE_FREE) && 3153 !(zio->io_flags & ZIO_FLAG_SCAN_THREAD) && 3154 zio->io_error == ENXIO && 3155 spa_load_state(spa) == SPA_LOAD_NONE && 3156 spa_get_failmode(spa) != ZIO_FAILURE_MODE_CONTINUE) 3157 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 3158 3159 if (!(zio->io_flags & ZIO_FLAG_CANFAIL) && !zio->io_reexecute) 3160 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 3161 3162 /* 3163 * Here is a possibly good place to attempt to do 3164 * either combinatorial reconstruction or error correction 3165 * based on checksums. It also might be a good place 3166 * to send out preliminary ereports before we suspend 3167 * processing. 3168 */ 3169 } 3170 3171 /* 3172 * If there were logical child errors, they apply to us now. 3173 * We defer this until now to avoid conflating logical child 3174 * errors with errors that happened to the zio itself when 3175 * updating vdev stats and reporting FMA events above. 3176 */ 3177 zio_inherit_child_errors(zio, ZIO_CHILD_LOGICAL); 3178 3179 if ((zio->io_error || zio->io_reexecute) && 3180 IO_IS_ALLOCATING(zio) && zio->io_gang_leader == zio && 3181 !(zio->io_flags & (ZIO_FLAG_IO_REWRITE | ZIO_FLAG_NOPWRITE))) 3182 zio_dva_unallocate(zio, zio->io_gang_tree, bp); 3183 3184 zio_gang_tree_free(&zio->io_gang_tree); 3185 3186 /* 3187 * Godfather I/Os should never suspend. 3188 */ 3189 if ((zio->io_flags & ZIO_FLAG_GODFATHER) && 3190 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) 3191 zio->io_reexecute = 0; 3192 3193 if (zio->io_reexecute) { 3194 /* 3195 * This is a logical I/O that wants to reexecute. 3196 * 3197 * Reexecute is top-down. When an i/o fails, if it's not 3198 * the root, it simply notifies its parent and sticks around. 3199 * The parent, seeing that it still has children in zio_done(), 3200 * does the same. This percolates all the way up to the root. 3201 * The root i/o will reexecute or suspend the entire tree. 3202 * 3203 * This approach ensures that zio_reexecute() honors 3204 * all the original i/o dependency relationships, e.g. 3205 * parents not executing until children are ready. 3206 */ 3207 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 3208 3209 zio->io_gang_leader = NULL; 3210 3211 mutex_enter(&zio->io_lock); 3212 zio->io_state[ZIO_WAIT_DONE] = 1; 3213 mutex_exit(&zio->io_lock); 3214 3215 /* 3216 * "The Godfather" I/O monitors its children but is 3217 * not a true parent to them. It will track them through 3218 * the pipeline but severs its ties whenever they get into 3219 * trouble (e.g. suspended). This allows "The Godfather" 3220 * I/O to return status without blocking. 3221 */ 3222 for (pio = zio_walk_parents(zio); pio != NULL; pio = pio_next) { 3223 zio_link_t *zl = zio->io_walk_link; 3224 pio_next = zio_walk_parents(zio); 3225 3226 if ((pio->io_flags & ZIO_FLAG_GODFATHER) && 3227 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) { 3228 zio_remove_child(pio, zio, zl); 3229 zio_notify_parent(pio, zio, ZIO_WAIT_DONE); 3230 } 3231 } 3232 3233 if ((pio = zio_unique_parent(zio)) != NULL) { 3234 /* 3235 * We're not a root i/o, so there's nothing to do 3236 * but notify our parent. Don't propagate errors 3237 * upward since we haven't permanently failed yet. 3238 */ 3239 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER)); 3240 zio->io_flags |= ZIO_FLAG_DONT_PROPAGATE; 3241 zio_notify_parent(pio, zio, ZIO_WAIT_DONE); 3242 } else if (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND) { 3243 /* 3244 * We'd fail again if we reexecuted now, so suspend 3245 * until conditions improve (e.g. device comes online). 3246 */ 3247 zio_suspend(spa, zio); 3248 } else { 3249 /* 3250 * Reexecution is potentially a huge amount of work. 3251 * Hand it off to the otherwise-unused claim taskq. 3252 */ 3253 ASSERT(zio->io_tqent.tqent_next == NULL); 3254 spa_taskq_dispatch_ent(spa, ZIO_TYPE_CLAIM, 3255 ZIO_TASKQ_ISSUE, (task_func_t *)zio_reexecute, zio, 3256 0, &zio->io_tqent); 3257 } 3258 return (ZIO_PIPELINE_STOP); 3259 } 3260 3261 ASSERT(zio->io_child_count == 0); 3262 ASSERT(zio->io_reexecute == 0); 3263 ASSERT(zio->io_error == 0 || (zio->io_flags & ZIO_FLAG_CANFAIL)); 3264 3265 /* 3266 * Report any checksum errors, since the I/O is complete. 3267 */ 3268 while (zio->io_cksum_report != NULL) { 3269 zio_cksum_report_t *zcr = zio->io_cksum_report; 3270 zio->io_cksum_report = zcr->zcr_next; 3271 zcr->zcr_next = NULL; 3272 zcr->zcr_finish(zcr, NULL); 3273 zfs_ereport_free_checksum(zcr); 3274 } 3275 3276 /* 3277 * It is the responsibility of the done callback to ensure that this 3278 * particular zio is no longer discoverable for adoption, and as 3279 * such, cannot acquire any new parents. 3280 */ 3281 if (zio->io_done) 3282 zio->io_done(zio); 3283 3284 mutex_enter(&zio->io_lock); 3285 zio->io_state[ZIO_WAIT_DONE] = 1; 3286 mutex_exit(&zio->io_lock); 3287 3288 for (pio = zio_walk_parents(zio); pio != NULL; pio = pio_next) { 3289 zio_link_t *zl = zio->io_walk_link; 3290 pio_next = zio_walk_parents(zio); 3291 zio_remove_child(pio, zio, zl); 3292 zio_notify_parent(pio, zio, ZIO_WAIT_DONE); 3293 } 3294 3295 if (zio->io_waiter != NULL) { 3296 mutex_enter(&zio->io_lock); 3297 zio->io_executor = NULL; 3298 cv_broadcast(&zio->io_cv); 3299 mutex_exit(&zio->io_lock); 3300 } else { 3301 zio_destroy(zio); 3302 } 3303 3304 return (ZIO_PIPELINE_STOP); 3305 } 3306 3307 /* 3308 * ========================================================================== 3309 * I/O pipeline definition 3310 * ========================================================================== 3311 */ 3312 static zio_pipe_stage_t *zio_pipeline[] = { 3313 NULL, 3314 zio_read_bp_init, 3315 zio_free_bp_init, 3316 zio_issue_async, 3317 zio_write_bp_init, 3318 zio_checksum_generate, 3319 zio_nop_write, 3320 zio_ddt_read_start, 3321 zio_ddt_read_done, 3322 zio_ddt_write, 3323 zio_ddt_free, 3324 zio_gang_assemble, 3325 zio_gang_issue, 3326 zio_dva_allocate, 3327 zio_dva_free, 3328 zio_dva_claim, 3329 zio_ready, 3330 zio_vdev_io_start, 3331 zio_vdev_io_done, 3332 zio_vdev_io_assess, 3333 zio_checksum_verify, 3334 zio_done 3335 }; 3336 3337 3338 3339 3340 /* 3341 * Compare two zbookmark_phys_t's to see which we would reach first in a 3342 * pre-order traversal of the object tree. 3343 * 3344 * This is simple in every case aside from the meta-dnode object. For all other 3345 * objects, we traverse them in order (object 1 before object 2, and so on). 3346 * However, all of these objects are traversed while traversing object 0, since 3347 * the data it points to is the list of objects. Thus, we need to convert to a 3348 * canonical representation so we can compare meta-dnode bookmarks to 3349 * non-meta-dnode bookmarks. 3350 * 3351 * We do this by calculating "equivalents" for each field of the zbookmark. 3352 * zbookmarks outside of the meta-dnode use their own object and level, and 3353 * calculate the level 0 equivalent (the first L0 blkid that is contained in the 3354 * blocks this bookmark refers to) by multiplying their blkid by their span 3355 * (the number of L0 blocks contained within one block at their level). 3356 * zbookmarks inside the meta-dnode calculate their object equivalent 3357 * (which is L0equiv * dnodes per data block), use 0 for their L0equiv, and use 3358 * level + 1<<31 (any value larger than a level could ever be) for their level. 3359 * This causes them to always compare before a bookmark in their object 3360 * equivalent, compare appropriately to bookmarks in other objects, and to 3361 * compare appropriately to other bookmarks in the meta-dnode. 3362 */ 3363 int 3364 zbookmark_compare(uint16_t dbss1, uint8_t ibs1, uint16_t dbss2, uint8_t ibs2, 3365 const zbookmark_phys_t *zb1, const zbookmark_phys_t *zb2) 3366 { 3367 /* 3368 * These variables represent the "equivalent" values for the zbookmark, 3369 * after converting zbookmarks inside the meta dnode to their 3370 * normal-object equivalents. 3371 */ 3372 uint64_t zb1obj, zb2obj; 3373 uint64_t zb1L0, zb2L0; 3374 uint64_t zb1level, zb2level; 3375 3376 if (zb1->zb_object == zb2->zb_object && 3377 zb1->zb_level == zb2->zb_level && 3378 zb1->zb_blkid == zb2->zb_blkid) 3379 return (0); 3380 3381 /* 3382 * BP_SPANB calculates the span in blocks. 3383 */ 3384 zb1L0 = (zb1->zb_blkid) * BP_SPANB(ibs1, zb1->zb_level); 3385 zb2L0 = (zb2->zb_blkid) * BP_SPANB(ibs2, zb2->zb_level); 3386 3387 if (zb1->zb_object == DMU_META_DNODE_OBJECT) { 3388 zb1obj = zb1L0 * (dbss1 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT)); 3389 zb1L0 = 0; 3390 zb1level = zb1->zb_level + COMPARE_META_LEVEL; 3391 } else { 3392 zb1obj = zb1->zb_object; 3393 zb1level = zb1->zb_level; 3394 } 3395 3396 if (zb2->zb_object == DMU_META_DNODE_OBJECT) { 3397 zb2obj = zb2L0 * (dbss2 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT)); 3398 zb2L0 = 0; 3399 zb2level = zb2->zb_level + COMPARE_META_LEVEL; 3400 } else { 3401 zb2obj = zb2->zb_object; 3402 zb2level = zb2->zb_level; 3403 } 3404 3405 /* Now that we have a canonical representation, do the comparison. */ 3406 if (zb1obj != zb2obj) 3407 return (zb1obj < zb2obj ? -1 : 1); 3408 else if (zb1L0 != zb2L0) 3409 return (zb1L0 < zb2L0 ? -1 : 1); 3410 else if (zb1level != zb2level) 3411 return (zb1level > zb2level ? -1 : 1); 3412 /* 3413 * This can (theoretically) happen if the bookmarks have the same object 3414 * and level, but different blkids, if the block sizes are not the same. 3415 * There is presently no way to change the indirect block sizes 3416 */ 3417 return (0); 3418 } 3419 3420 /* 3421 * This function checks the following: given that last_block is the place that 3422 * our traversal stopped last time, does that guarantee that we've visited 3423 * every node under subtree_root? Therefore, we can't just use the raw output 3424 * of zbookmark_compare. We have to pass in a modified version of 3425 * subtree_root; by incrementing the block id, and then checking whether 3426 * last_block is before or equal to that, we can tell whether or not having 3427 * visited last_block implies that all of subtree_root's children have been 3428 * visited. 3429 */ 3430 boolean_t 3431 zbookmark_subtree_completed(const dnode_phys_t *dnp, 3432 const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block) 3433 { 3434 zbookmark_phys_t mod_zb = *subtree_root; 3435 mod_zb.zb_blkid++; 3436 ASSERT(last_block->zb_level == 0); 3437 3438 /* The objset_phys_t isn't before anything. */ 3439 if (dnp == NULL) 3440 return (B_FALSE); 3441 3442 /* 3443 * We pass in 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT) for the 3444 * data block size in sectors, because that variable is only used if 3445 * the bookmark refers to a block in the meta-dnode. Since we don't 3446 * know without examining it what object it refers to, and there's no 3447 * harm in passing in this value in other cases, we always pass it in. 3448 * 3449 * We pass in 0 for the indirect block size shift because zb2 must be 3450 * level 0. The indirect block size is only used to calculate the span 3451 * of the bookmark, but since the bookmark must be level 0, the span is 3452 * always 1, so the math works out. 3453 * 3454 * If you make changes to how the zbookmark_compare code works, be sure 3455 * to make sure that this code still works afterwards. 3456 */ 3457 return (zbookmark_compare(dnp->dn_datablkszsec, dnp->dn_indblkshift, 3458 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT), 0, &mod_zb, 3459 last_block) <= 0); 3460 } 3461