1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * CDDL HEADER START 4 * 5 * The contents of this file are subject to the terms of the 6 * Common Development and Distribution License (the "License"). 7 * You may not use this file except in compliance with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or https://opensource.org/licenses/CDDL-1.0. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Copyright (c) 2011, 2022 by Delphix. All rights reserved. 25 * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved. 26 * Copyright (c) 2017, Intel Corporation. 27 * Copyright (c) 2019, 2023, 2024, 2025, Klara, Inc. 28 * Copyright (c) 2019, Allan Jude 29 * Copyright (c) 2021, Datto, Inc. 30 * Copyright (c) 2021, 2024 by George Melikov. All rights reserved. 31 */ 32 33 #include <sys/sysmacros.h> 34 #include <sys/zfs_context.h> 35 #include <sys/fm/fs/zfs.h> 36 #include <sys/spa.h> 37 #include <sys/txg.h> 38 #include <sys/spa_impl.h> 39 #include <sys/vdev_impl.h> 40 #include <sys/vdev_trim.h> 41 #include <sys/zio_impl.h> 42 #include <sys/zio_compress.h> 43 #include <sys/zio_checksum.h> 44 #include <sys/dmu_objset.h> 45 #include <sys/arc.h> 46 #include <sys/brt.h> 47 #include <sys/ddt.h> 48 #include <sys/blkptr.h> 49 #include <sys/zfeature.h> 50 #include <sys/dsl_scan.h> 51 #include <sys/metaslab_impl.h> 52 #include <sys/time.h> 53 #include <sys/trace_zfs.h> 54 #include <sys/abd.h> 55 #include <sys/dsl_crypt.h> 56 #include <cityhash.h> 57 58 /* 59 * ========================================================================== 60 * I/O type descriptions 61 * ========================================================================== 62 */ 63 const char *const zio_type_name[ZIO_TYPES] = { 64 /* 65 * Note: Linux kernel thread name length is limited 66 * so these names will differ from upstream open zfs. 67 */ 68 "z_null", "z_rd", "z_wr", "z_fr", "z_cl", "z_flush", "z_trim" 69 }; 70 71 int zio_dva_throttle_enabled = B_TRUE; 72 static int zio_deadman_log_all = B_FALSE; 73 74 /* 75 * ========================================================================== 76 * I/O kmem caches 77 * ========================================================================== 78 */ 79 static kmem_cache_t *zio_cache; 80 static kmem_cache_t *zio_link_cache; 81 kmem_cache_t *zio_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT]; 82 kmem_cache_t *zio_data_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT]; 83 #if defined(ZFS_DEBUG) && !defined(_KERNEL) 84 static uint64_t zio_buf_cache_allocs[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT]; 85 static uint64_t zio_buf_cache_frees[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT]; 86 #endif 87 88 /* Mark IOs as "slow" if they take longer than 30 seconds */ 89 static uint_t zio_slow_io_ms = (30 * MILLISEC); 90 91 #define BP_SPANB(indblkshift, level) \ 92 (((uint64_t)1) << ((level) * ((indblkshift) - SPA_BLKPTRSHIFT))) 93 #define COMPARE_META_LEVEL 0x80000000ul 94 /* 95 * The following actions directly effect the spa's sync-to-convergence logic. 96 * The values below define the sync pass when we start performing the action. 97 * Care should be taken when changing these values as they directly impact 98 * spa_sync() performance. Tuning these values may introduce subtle performance 99 * pathologies and should only be done in the context of performance analysis. 100 * These tunables will eventually be removed and replaced with #defines once 101 * enough analysis has been done to determine optimal values. 102 * 103 * The 'zfs_sync_pass_deferred_free' pass must be greater than 1 to ensure that 104 * regular blocks are not deferred. 105 * 106 * Starting in sync pass 8 (zfs_sync_pass_dont_compress), we disable 107 * compression (including of metadata). In practice, we don't have this 108 * many sync passes, so this has no effect. 109 * 110 * The original intent was that disabling compression would help the sync 111 * passes to converge. However, in practice disabling compression increases 112 * the average number of sync passes, because when we turn compression off, a 113 * lot of block's size will change and thus we have to re-allocate (not 114 * overwrite) them. It also increases the number of 128KB allocations (e.g. 115 * for indirect blocks and spacemaps) because these will not be compressed. 116 * The 128K allocations are especially detrimental to performance on highly 117 * fragmented systems, which may have very few free segments of this size, 118 * and may need to load new metaslabs to satisfy 128K allocations. 119 */ 120 121 /* defer frees starting in this pass */ 122 uint_t zfs_sync_pass_deferred_free = 2; 123 124 /* don't compress starting in this pass */ 125 static uint_t zfs_sync_pass_dont_compress = 8; 126 127 /* rewrite new bps starting in this pass */ 128 static uint_t zfs_sync_pass_rewrite = 2; 129 130 /* 131 * An allocating zio is one that either currently has the DVA allocate 132 * stage set or will have it later in its lifetime. 133 */ 134 #define IO_IS_ALLOCATING(zio) ((zio)->io_orig_pipeline & ZIO_STAGE_DVA_ALLOCATE) 135 136 /* 137 * Enable smaller cores by excluding metadata 138 * allocations as well. 139 */ 140 int zio_exclude_metadata = 0; 141 static int zio_requeue_io_start_cut_in_line = 1; 142 143 #ifdef ZFS_DEBUG 144 static const int zio_buf_debug_limit = 16384; 145 #else 146 static const int zio_buf_debug_limit = 0; 147 #endif 148 149 typedef struct zio_stats { 150 kstat_named_t ziostat_total_allocations; 151 kstat_named_t ziostat_alloc_class_fallbacks; 152 kstat_named_t ziostat_gang_writes; 153 kstat_named_t ziostat_gang_multilevel; 154 } zio_stats_t; 155 156 static zio_stats_t zio_stats = { 157 { "total_allocations", KSTAT_DATA_UINT64 }, 158 { "alloc_class_fallbacks", KSTAT_DATA_UINT64 }, 159 { "gang_writes", KSTAT_DATA_UINT64 }, 160 { "gang_multilevel", KSTAT_DATA_UINT64 }, 161 }; 162 163 struct { 164 wmsum_t ziostat_total_allocations; 165 wmsum_t ziostat_alloc_class_fallbacks; 166 wmsum_t ziostat_gang_writes; 167 wmsum_t ziostat_gang_multilevel; 168 } ziostat_sums; 169 170 #define ZIOSTAT_BUMP(stat) wmsum_add(&ziostat_sums.stat, 1); 171 172 static kstat_t *zio_ksp; 173 174 static inline void __zio_execute(zio_t *zio); 175 176 static void zio_taskq_dispatch(zio_t *, zio_taskq_type_t, boolean_t); 177 178 static int 179 zio_kstats_update(kstat_t *ksp, int rw) 180 { 181 zio_stats_t *zs = ksp->ks_data; 182 if (rw == KSTAT_WRITE) 183 return (EACCES); 184 185 zs->ziostat_total_allocations.value.ui64 = 186 wmsum_value(&ziostat_sums.ziostat_total_allocations); 187 zs->ziostat_alloc_class_fallbacks.value.ui64 = 188 wmsum_value(&ziostat_sums.ziostat_alloc_class_fallbacks); 189 zs->ziostat_gang_writes.value.ui64 = 190 wmsum_value(&ziostat_sums.ziostat_gang_writes); 191 zs->ziostat_gang_multilevel.value.ui64 = 192 wmsum_value(&ziostat_sums.ziostat_gang_multilevel); 193 return (0); 194 } 195 196 void 197 zio_init(void) 198 { 199 size_t c; 200 201 zio_cache = kmem_cache_create("zio_cache", 202 sizeof (zio_t), 0, NULL, NULL, NULL, NULL, NULL, 0); 203 zio_link_cache = kmem_cache_create("zio_link_cache", 204 sizeof (zio_link_t), 0, NULL, NULL, NULL, NULL, NULL, 0); 205 206 wmsum_init(&ziostat_sums.ziostat_total_allocations, 0); 207 wmsum_init(&ziostat_sums.ziostat_alloc_class_fallbacks, 0); 208 wmsum_init(&ziostat_sums.ziostat_gang_writes, 0); 209 wmsum_init(&ziostat_sums.ziostat_gang_multilevel, 0); 210 zio_ksp = kstat_create("zfs", 0, "zio_stats", 211 "misc", KSTAT_TYPE_NAMED, sizeof (zio_stats) / 212 sizeof (kstat_named_t), KSTAT_FLAG_VIRTUAL); 213 if (zio_ksp != NULL) { 214 zio_ksp->ks_data = &zio_stats; 215 zio_ksp->ks_update = zio_kstats_update; 216 kstat_install(zio_ksp); 217 } 218 219 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) { 220 size_t size = (c + 1) << SPA_MINBLOCKSHIFT; 221 size_t align, cflags, data_cflags; 222 char name[32]; 223 224 /* 225 * Create cache for each half-power of 2 size, starting from 226 * SPA_MINBLOCKSIZE. It should give us memory space efficiency 227 * of ~7/8, sufficient for transient allocations mostly using 228 * these caches. 229 */ 230 size_t p2 = size; 231 while (!ISP2(p2)) 232 p2 &= p2 - 1; 233 if (!IS_P2ALIGNED(size, p2 / 2)) 234 continue; 235 236 #ifndef _KERNEL 237 /* 238 * If we are using watchpoints, put each buffer on its own page, 239 * to eliminate the performance overhead of trapping to the 240 * kernel when modifying a non-watched buffer that shares the 241 * page with a watched buffer. 242 */ 243 if (arc_watch && !IS_P2ALIGNED(size, PAGESIZE)) 244 continue; 245 #endif 246 247 if (IS_P2ALIGNED(size, PAGESIZE)) 248 align = PAGESIZE; 249 else 250 align = 1 << (highbit64(size ^ (size - 1)) - 1); 251 252 cflags = (zio_exclude_metadata || size > zio_buf_debug_limit) ? 253 KMC_NODEBUG : 0; 254 data_cflags = KMC_NODEBUG; 255 if (abd_size_alloc_linear(size)) { 256 cflags |= KMC_RECLAIMABLE; 257 data_cflags |= KMC_RECLAIMABLE; 258 } 259 if (cflags == data_cflags) { 260 /* 261 * Resulting kmem caches would be identical. 262 * Save memory by creating only one. 263 */ 264 (void) snprintf(name, sizeof (name), 265 "zio_buf_comb_%lu", (ulong_t)size); 266 zio_buf_cache[c] = kmem_cache_create(name, size, align, 267 NULL, NULL, NULL, NULL, NULL, cflags); 268 zio_data_buf_cache[c] = zio_buf_cache[c]; 269 continue; 270 } 271 (void) snprintf(name, sizeof (name), "zio_buf_%lu", 272 (ulong_t)size); 273 zio_buf_cache[c] = kmem_cache_create(name, size, align, 274 NULL, NULL, NULL, NULL, NULL, cflags); 275 276 (void) snprintf(name, sizeof (name), "zio_data_buf_%lu", 277 (ulong_t)size); 278 zio_data_buf_cache[c] = kmem_cache_create(name, size, align, 279 NULL, NULL, NULL, NULL, NULL, data_cflags); 280 } 281 282 while (--c != 0) { 283 ASSERT(zio_buf_cache[c] != NULL); 284 if (zio_buf_cache[c - 1] == NULL) 285 zio_buf_cache[c - 1] = zio_buf_cache[c]; 286 287 ASSERT(zio_data_buf_cache[c] != NULL); 288 if (zio_data_buf_cache[c - 1] == NULL) 289 zio_data_buf_cache[c - 1] = zio_data_buf_cache[c]; 290 } 291 292 zio_inject_init(); 293 294 lz4_init(); 295 } 296 297 void 298 zio_fini(void) 299 { 300 size_t n = SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; 301 302 #if defined(ZFS_DEBUG) && !defined(_KERNEL) 303 for (size_t i = 0; i < n; i++) { 304 if (zio_buf_cache_allocs[i] != zio_buf_cache_frees[i]) 305 (void) printf("zio_fini: [%d] %llu != %llu\n", 306 (int)((i + 1) << SPA_MINBLOCKSHIFT), 307 (long long unsigned)zio_buf_cache_allocs[i], 308 (long long unsigned)zio_buf_cache_frees[i]); 309 } 310 #endif 311 312 /* 313 * The same kmem cache can show up multiple times in both zio_buf_cache 314 * and zio_data_buf_cache. Do a wasteful but trivially correct scan to 315 * sort it out. 316 */ 317 for (size_t i = 0; i < n; i++) { 318 kmem_cache_t *cache = zio_buf_cache[i]; 319 if (cache == NULL) 320 continue; 321 for (size_t j = i; j < n; j++) { 322 if (cache == zio_buf_cache[j]) 323 zio_buf_cache[j] = NULL; 324 if (cache == zio_data_buf_cache[j]) 325 zio_data_buf_cache[j] = NULL; 326 } 327 kmem_cache_destroy(cache); 328 } 329 330 for (size_t i = 0; i < n; i++) { 331 kmem_cache_t *cache = zio_data_buf_cache[i]; 332 if (cache == NULL) 333 continue; 334 for (size_t j = i; j < n; j++) { 335 if (cache == zio_data_buf_cache[j]) 336 zio_data_buf_cache[j] = NULL; 337 } 338 kmem_cache_destroy(cache); 339 } 340 341 for (size_t i = 0; i < n; i++) { 342 VERIFY3P(zio_buf_cache[i], ==, NULL); 343 VERIFY3P(zio_data_buf_cache[i], ==, NULL); 344 } 345 346 if (zio_ksp != NULL) { 347 kstat_delete(zio_ksp); 348 zio_ksp = NULL; 349 } 350 351 wmsum_fini(&ziostat_sums.ziostat_total_allocations); 352 wmsum_fini(&ziostat_sums.ziostat_alloc_class_fallbacks); 353 wmsum_fini(&ziostat_sums.ziostat_gang_writes); 354 wmsum_fini(&ziostat_sums.ziostat_gang_multilevel); 355 356 kmem_cache_destroy(zio_link_cache); 357 kmem_cache_destroy(zio_cache); 358 359 zio_inject_fini(); 360 361 lz4_fini(); 362 } 363 364 /* 365 * ========================================================================== 366 * Allocate and free I/O buffers 367 * ========================================================================== 368 */ 369 370 #if defined(ZFS_DEBUG) && defined(_KERNEL) 371 #define ZFS_ZIO_BUF_CANARY 1 372 #endif 373 374 #ifdef ZFS_ZIO_BUF_CANARY 375 static const ulong_t zio_buf_canary = (ulong_t)0xdeadc0dedead210b; 376 377 /* 378 * Use empty space after the buffer to detect overflows. 379 * 380 * Since zio_init() creates kmem caches only for certain set of buffer sizes, 381 * allocations of different sizes may have some unused space after the data. 382 * Filling part of that space with a known pattern on allocation and checking 383 * it on free should allow us to detect some buffer overflows. 384 */ 385 static void 386 zio_buf_put_canary(ulong_t *p, size_t size, kmem_cache_t **cache, size_t c) 387 { 388 size_t off = P2ROUNDUP(size, sizeof (ulong_t)); 389 ulong_t *canary = p + off / sizeof (ulong_t); 390 size_t asize = (c + 1) << SPA_MINBLOCKSHIFT; 391 if (c + 1 < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT && 392 cache[c] == cache[c + 1]) 393 asize = (c + 2) << SPA_MINBLOCKSHIFT; 394 for (; off < asize; canary++, off += sizeof (ulong_t)) 395 *canary = zio_buf_canary; 396 } 397 398 static void 399 zio_buf_check_canary(ulong_t *p, size_t size, kmem_cache_t **cache, size_t c) 400 { 401 size_t off = P2ROUNDUP(size, sizeof (ulong_t)); 402 ulong_t *canary = p + off / sizeof (ulong_t); 403 size_t asize = (c + 1) << SPA_MINBLOCKSHIFT; 404 if (c + 1 < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT && 405 cache[c] == cache[c + 1]) 406 asize = (c + 2) << SPA_MINBLOCKSHIFT; 407 for (; off < asize; canary++, off += sizeof (ulong_t)) { 408 if (unlikely(*canary != zio_buf_canary)) { 409 PANIC("ZIO buffer overflow %p (%zu) + %zu %#lx != %#lx", 410 p, size, (canary - p) * sizeof (ulong_t), 411 *canary, zio_buf_canary); 412 } 413 } 414 } 415 #endif 416 417 /* 418 * Use zio_buf_alloc to allocate ZFS metadata. This data will appear in a 419 * crashdump if the kernel panics, so use it judiciously. Obviously, it's 420 * useful to inspect ZFS metadata, but if possible, we should avoid keeping 421 * excess / transient data in-core during a crashdump. 422 */ 423 void * 424 zio_buf_alloc(size_t size) 425 { 426 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 427 428 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 429 #if defined(ZFS_DEBUG) && !defined(_KERNEL) 430 atomic_add_64(&zio_buf_cache_allocs[c], 1); 431 #endif 432 433 void *p = kmem_cache_alloc(zio_buf_cache[c], KM_PUSHPAGE); 434 #ifdef ZFS_ZIO_BUF_CANARY 435 zio_buf_put_canary(p, size, zio_buf_cache, c); 436 #endif 437 return (p); 438 } 439 440 /* 441 * Use zio_data_buf_alloc to allocate data. The data will not appear in a 442 * crashdump if the kernel panics. This exists so that we will limit the amount 443 * of ZFS data that shows up in a kernel crashdump. (Thus reducing the amount 444 * of kernel heap dumped to disk when the kernel panics) 445 */ 446 void * 447 zio_data_buf_alloc(size_t size) 448 { 449 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 450 451 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 452 453 void *p = kmem_cache_alloc(zio_data_buf_cache[c], KM_PUSHPAGE); 454 #ifdef ZFS_ZIO_BUF_CANARY 455 zio_buf_put_canary(p, size, zio_data_buf_cache, c); 456 #endif 457 return (p); 458 } 459 460 void 461 zio_buf_free(void *buf, size_t size) 462 { 463 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 464 465 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 466 #if defined(ZFS_DEBUG) && !defined(_KERNEL) 467 atomic_add_64(&zio_buf_cache_frees[c], 1); 468 #endif 469 470 #ifdef ZFS_ZIO_BUF_CANARY 471 zio_buf_check_canary(buf, size, zio_buf_cache, c); 472 #endif 473 kmem_cache_free(zio_buf_cache[c], buf); 474 } 475 476 void 477 zio_data_buf_free(void *buf, size_t size) 478 { 479 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT; 480 481 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT); 482 483 #ifdef ZFS_ZIO_BUF_CANARY 484 zio_buf_check_canary(buf, size, zio_data_buf_cache, c); 485 #endif 486 kmem_cache_free(zio_data_buf_cache[c], buf); 487 } 488 489 static void 490 zio_abd_free(void *abd, size_t size) 491 { 492 (void) size; 493 abd_free((abd_t *)abd); 494 } 495 496 /* 497 * ========================================================================== 498 * Push and pop I/O transform buffers 499 * ========================================================================== 500 */ 501 void 502 zio_push_transform(zio_t *zio, abd_t *data, uint64_t size, uint64_t bufsize, 503 zio_transform_func_t *transform) 504 { 505 zio_transform_t *zt = kmem_alloc(sizeof (zio_transform_t), KM_SLEEP); 506 507 zt->zt_orig_abd = zio->io_abd; 508 zt->zt_orig_size = zio->io_size; 509 zt->zt_bufsize = bufsize; 510 zt->zt_transform = transform; 511 512 zt->zt_next = zio->io_transform_stack; 513 zio->io_transform_stack = zt; 514 515 zio->io_abd = data; 516 zio->io_size = size; 517 } 518 519 void 520 zio_pop_transforms(zio_t *zio) 521 { 522 zio_transform_t *zt; 523 524 while ((zt = zio->io_transform_stack) != NULL) { 525 if (zt->zt_transform != NULL) 526 zt->zt_transform(zio, 527 zt->zt_orig_abd, zt->zt_orig_size); 528 529 if (zt->zt_bufsize != 0) 530 abd_free(zio->io_abd); 531 532 zio->io_abd = zt->zt_orig_abd; 533 zio->io_size = zt->zt_orig_size; 534 zio->io_transform_stack = zt->zt_next; 535 536 kmem_free(zt, sizeof (zio_transform_t)); 537 } 538 } 539 540 /* 541 * ========================================================================== 542 * I/O transform callbacks for subblocks, decompression, and decryption 543 * ========================================================================== 544 */ 545 static void 546 zio_subblock(zio_t *zio, abd_t *data, uint64_t size) 547 { 548 ASSERT(zio->io_size > size); 549 550 if (zio->io_type == ZIO_TYPE_READ) 551 abd_copy(data, zio->io_abd, size); 552 } 553 554 static void 555 zio_decompress(zio_t *zio, abd_t *data, uint64_t size) 556 { 557 if (zio->io_error == 0) { 558 int ret = zio_decompress_data(BP_GET_COMPRESS(zio->io_bp), 559 zio->io_abd, data, zio->io_size, size, 560 &zio->io_prop.zp_complevel); 561 562 if (zio_injection_enabled && ret == 0) 563 ret = zio_handle_fault_injection(zio, EINVAL); 564 565 if (ret != 0) 566 zio->io_error = SET_ERROR(EIO); 567 } 568 } 569 570 static void 571 zio_decrypt(zio_t *zio, abd_t *data, uint64_t size) 572 { 573 int ret; 574 void *tmp; 575 blkptr_t *bp = zio->io_bp; 576 spa_t *spa = zio->io_spa; 577 uint64_t dsobj = zio->io_bookmark.zb_objset; 578 uint64_t lsize = BP_GET_LSIZE(bp); 579 dmu_object_type_t ot = BP_GET_TYPE(bp); 580 uint8_t salt[ZIO_DATA_SALT_LEN]; 581 uint8_t iv[ZIO_DATA_IV_LEN]; 582 uint8_t mac[ZIO_DATA_MAC_LEN]; 583 boolean_t no_crypt = B_FALSE; 584 585 ASSERT(BP_USES_CRYPT(bp)); 586 ASSERT3U(size, !=, 0); 587 588 if (zio->io_error != 0) 589 return; 590 591 /* 592 * Verify the cksum of MACs stored in an indirect bp. It will always 593 * be possible to verify this since it does not require an encryption 594 * key. 595 */ 596 if (BP_HAS_INDIRECT_MAC_CKSUM(bp)) { 597 zio_crypt_decode_mac_bp(bp, mac); 598 599 if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF) { 600 /* 601 * We haven't decompressed the data yet, but 602 * zio_crypt_do_indirect_mac_checksum() requires 603 * decompressed data to be able to parse out the MACs 604 * from the indirect block. We decompress it now and 605 * throw away the result after we are finished. 606 */ 607 abd_t *abd = abd_alloc_linear(lsize, B_TRUE); 608 ret = zio_decompress_data(BP_GET_COMPRESS(bp), 609 zio->io_abd, abd, zio->io_size, lsize, 610 &zio->io_prop.zp_complevel); 611 if (ret != 0) { 612 abd_free(abd); 613 ret = SET_ERROR(EIO); 614 goto error; 615 } 616 ret = zio_crypt_do_indirect_mac_checksum_abd(B_FALSE, 617 abd, lsize, BP_SHOULD_BYTESWAP(bp), mac); 618 abd_free(abd); 619 } else { 620 ret = zio_crypt_do_indirect_mac_checksum_abd(B_FALSE, 621 zio->io_abd, size, BP_SHOULD_BYTESWAP(bp), mac); 622 } 623 abd_copy(data, zio->io_abd, size); 624 625 if (zio_injection_enabled && ot != DMU_OT_DNODE && ret == 0) { 626 ret = zio_handle_decrypt_injection(spa, 627 &zio->io_bookmark, ot, ECKSUM); 628 } 629 if (ret != 0) 630 goto error; 631 632 return; 633 } 634 635 /* 636 * If this is an authenticated block, just check the MAC. It would be 637 * nice to separate this out into its own flag, but when this was done, 638 * we had run out of bits in what is now zio_flag_t. Future cleanup 639 * could make this a flag bit. 640 */ 641 if (BP_IS_AUTHENTICATED(bp)) { 642 if (ot == DMU_OT_OBJSET) { 643 ret = spa_do_crypt_objset_mac_abd(B_FALSE, spa, 644 dsobj, zio->io_abd, size, BP_SHOULD_BYTESWAP(bp)); 645 } else { 646 zio_crypt_decode_mac_bp(bp, mac); 647 ret = spa_do_crypt_mac_abd(B_FALSE, spa, dsobj, 648 zio->io_abd, size, mac); 649 if (zio_injection_enabled && ret == 0) { 650 ret = zio_handle_decrypt_injection(spa, 651 &zio->io_bookmark, ot, ECKSUM); 652 } 653 } 654 abd_copy(data, zio->io_abd, size); 655 656 if (ret != 0) 657 goto error; 658 659 return; 660 } 661 662 zio_crypt_decode_params_bp(bp, salt, iv); 663 664 if (ot == DMU_OT_INTENT_LOG) { 665 tmp = abd_borrow_buf_copy(zio->io_abd, sizeof (zil_chain_t)); 666 zio_crypt_decode_mac_zil(tmp, mac); 667 abd_return_buf(zio->io_abd, tmp, sizeof (zil_chain_t)); 668 } else { 669 zio_crypt_decode_mac_bp(bp, mac); 670 } 671 672 ret = spa_do_crypt_abd(B_FALSE, spa, &zio->io_bookmark, BP_GET_TYPE(bp), 673 BP_GET_DEDUP(bp), BP_SHOULD_BYTESWAP(bp), salt, iv, mac, size, data, 674 zio->io_abd, &no_crypt); 675 if (no_crypt) 676 abd_copy(data, zio->io_abd, size); 677 678 if (ret != 0) 679 goto error; 680 681 return; 682 683 error: 684 /* assert that the key was found unless this was speculative */ 685 ASSERT(ret != EACCES || (zio->io_flags & ZIO_FLAG_SPECULATIVE)); 686 687 /* 688 * If there was a decryption / authentication error return EIO as 689 * the io_error. If this was not a speculative zio, create an ereport. 690 */ 691 if (ret == ECKSUM) { 692 zio->io_error = SET_ERROR(EIO); 693 if ((zio->io_flags & ZIO_FLAG_SPECULATIVE) == 0) { 694 spa_log_error(spa, &zio->io_bookmark, 695 BP_GET_LOGICAL_BIRTH(zio->io_bp)); 696 (void) zfs_ereport_post(FM_EREPORT_ZFS_AUTHENTICATION, 697 spa, NULL, &zio->io_bookmark, zio, 0); 698 } 699 } else { 700 zio->io_error = ret; 701 } 702 } 703 704 /* 705 * ========================================================================== 706 * I/O parent/child relationships and pipeline interlocks 707 * ========================================================================== 708 */ 709 zio_t * 710 zio_walk_parents(zio_t *cio, zio_link_t **zl) 711 { 712 list_t *pl = &cio->io_parent_list; 713 714 *zl = (*zl == NULL) ? list_head(pl) : list_next(pl, *zl); 715 if (*zl == NULL) 716 return (NULL); 717 718 ASSERT((*zl)->zl_child == cio); 719 return ((*zl)->zl_parent); 720 } 721 722 zio_t * 723 zio_walk_children(zio_t *pio, zio_link_t **zl) 724 { 725 list_t *cl = &pio->io_child_list; 726 727 ASSERT(MUTEX_HELD(&pio->io_lock)); 728 729 *zl = (*zl == NULL) ? list_head(cl) : list_next(cl, *zl); 730 if (*zl == NULL) 731 return (NULL); 732 733 ASSERT((*zl)->zl_parent == pio); 734 return ((*zl)->zl_child); 735 } 736 737 zio_t * 738 zio_unique_parent(zio_t *cio) 739 { 740 zio_link_t *zl = NULL; 741 zio_t *pio = zio_walk_parents(cio, &zl); 742 743 VERIFY3P(zio_walk_parents(cio, &zl), ==, NULL); 744 return (pio); 745 } 746 747 void 748 zio_add_child(zio_t *pio, zio_t *cio) 749 { 750 /* 751 * Logical I/Os can have logical, gang, or vdev children. 752 * Gang I/Os can have gang or vdev children. 753 * Vdev I/Os can only have vdev children. 754 * The following ASSERT captures all of these constraints. 755 */ 756 ASSERT3S(cio->io_child_type, <=, pio->io_child_type); 757 758 /* Parent should not have READY stage if child doesn't have it. */ 759 IMPLY((cio->io_pipeline & ZIO_STAGE_READY) == 0 && 760 (cio->io_child_type != ZIO_CHILD_VDEV), 761 (pio->io_pipeline & ZIO_STAGE_READY) == 0); 762 763 zio_link_t *zl = kmem_cache_alloc(zio_link_cache, KM_SLEEP); 764 zl->zl_parent = pio; 765 zl->zl_child = cio; 766 767 mutex_enter(&pio->io_lock); 768 mutex_enter(&cio->io_lock); 769 770 ASSERT(pio->io_state[ZIO_WAIT_DONE] == 0); 771 772 uint64_t *countp = pio->io_children[cio->io_child_type]; 773 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 774 countp[w] += !cio->io_state[w]; 775 776 list_insert_head(&pio->io_child_list, zl); 777 list_insert_head(&cio->io_parent_list, zl); 778 779 mutex_exit(&cio->io_lock); 780 mutex_exit(&pio->io_lock); 781 } 782 783 void 784 zio_add_child_first(zio_t *pio, zio_t *cio) 785 { 786 /* 787 * Logical I/Os can have logical, gang, or vdev children. 788 * Gang I/Os can have gang or vdev children. 789 * Vdev I/Os can only have vdev children. 790 * The following ASSERT captures all of these constraints. 791 */ 792 ASSERT3S(cio->io_child_type, <=, pio->io_child_type); 793 794 /* Parent should not have READY stage if child doesn't have it. */ 795 IMPLY((cio->io_pipeline & ZIO_STAGE_READY) == 0 && 796 (cio->io_child_type != ZIO_CHILD_VDEV), 797 (pio->io_pipeline & ZIO_STAGE_READY) == 0); 798 799 zio_link_t *zl = kmem_cache_alloc(zio_link_cache, KM_SLEEP); 800 zl->zl_parent = pio; 801 zl->zl_child = cio; 802 803 ASSERT(list_is_empty(&cio->io_parent_list)); 804 list_insert_head(&cio->io_parent_list, zl); 805 806 mutex_enter(&pio->io_lock); 807 808 ASSERT(pio->io_state[ZIO_WAIT_DONE] == 0); 809 810 uint64_t *countp = pio->io_children[cio->io_child_type]; 811 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 812 countp[w] += !cio->io_state[w]; 813 814 list_insert_head(&pio->io_child_list, zl); 815 816 mutex_exit(&pio->io_lock); 817 } 818 819 static void 820 zio_remove_child(zio_t *pio, zio_t *cio, zio_link_t *zl) 821 { 822 ASSERT(zl->zl_parent == pio); 823 ASSERT(zl->zl_child == cio); 824 825 mutex_enter(&pio->io_lock); 826 mutex_enter(&cio->io_lock); 827 828 list_remove(&pio->io_child_list, zl); 829 list_remove(&cio->io_parent_list, zl); 830 831 mutex_exit(&cio->io_lock); 832 mutex_exit(&pio->io_lock); 833 kmem_cache_free(zio_link_cache, zl); 834 } 835 836 static boolean_t 837 zio_wait_for_children(zio_t *zio, uint8_t childbits, enum zio_wait_type wait) 838 { 839 boolean_t waiting = B_FALSE; 840 841 mutex_enter(&zio->io_lock); 842 ASSERT(zio->io_stall == NULL); 843 for (int c = 0; c < ZIO_CHILD_TYPES; c++) { 844 if (!(ZIO_CHILD_BIT_IS_SET(childbits, c))) 845 continue; 846 847 uint64_t *countp = &zio->io_children[c][wait]; 848 if (*countp != 0) { 849 zio->io_stage >>= 1; 850 ASSERT3U(zio->io_stage, !=, ZIO_STAGE_OPEN); 851 zio->io_stall = countp; 852 waiting = B_TRUE; 853 break; 854 } 855 } 856 mutex_exit(&zio->io_lock); 857 return (waiting); 858 } 859 860 __attribute__((always_inline)) 861 static inline void 862 zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait, 863 zio_t **next_to_executep) 864 { 865 uint64_t *countp = &pio->io_children[zio->io_child_type][wait]; 866 int *errorp = &pio->io_child_error[zio->io_child_type]; 867 868 mutex_enter(&pio->io_lock); 869 if (zio->io_error && !(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE)) 870 *errorp = zio_worst_error(*errorp, zio->io_error); 871 pio->io_reexecute |= zio->io_reexecute; 872 ASSERT3U(*countp, >, 0); 873 874 /* 875 * Propogate the Direct I/O checksum verify failure to the parent. 876 */ 877 if (zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR) 878 pio->io_flags |= ZIO_FLAG_DIO_CHKSUM_ERR; 879 880 (*countp)--; 881 882 if (*countp == 0 && pio->io_stall == countp) { 883 zio_taskq_type_t type = 884 pio->io_stage < ZIO_STAGE_VDEV_IO_START ? ZIO_TASKQ_ISSUE : 885 ZIO_TASKQ_INTERRUPT; 886 pio->io_stall = NULL; 887 mutex_exit(&pio->io_lock); 888 889 /* 890 * If we can tell the caller to execute this parent next, do 891 * so. We do this if the parent's zio type matches the child's 892 * type, or if it's a zio_null() with no done callback, and so 893 * has no actual work to do. Otherwise dispatch the parent zio 894 * in its own taskq. 895 * 896 * Having the caller execute the parent when possible reduces 897 * locking on the zio taskq's, reduces context switch 898 * overhead, and has no recursion penalty. Note that one 899 * read from disk typically causes at least 3 zio's: a 900 * zio_null(), the logical zio_read(), and then a physical 901 * zio. When the physical ZIO completes, we are able to call 902 * zio_done() on all 3 of these zio's from one invocation of 903 * zio_execute() by returning the parent back to 904 * zio_execute(). Since the parent isn't executed until this 905 * thread returns back to zio_execute(), the caller should do 906 * so promptly. 907 * 908 * In other cases, dispatching the parent prevents 909 * overflowing the stack when we have deeply nested 910 * parent-child relationships, as we do with the "mega zio" 911 * of writes for spa_sync(), and the chain of ZIL blocks. 912 */ 913 if (next_to_executep != NULL && *next_to_executep == NULL && 914 (pio->io_type == zio->io_type || 915 (pio->io_type == ZIO_TYPE_NULL && !pio->io_done))) { 916 *next_to_executep = pio; 917 } else { 918 zio_taskq_dispatch(pio, type, B_FALSE); 919 } 920 } else { 921 mutex_exit(&pio->io_lock); 922 } 923 } 924 925 static void 926 zio_inherit_child_errors(zio_t *zio, enum zio_child c) 927 { 928 if (zio->io_child_error[c] != 0 && zio->io_error == 0) 929 zio->io_error = zio->io_child_error[c]; 930 } 931 932 int 933 zio_bookmark_compare(const void *x1, const void *x2) 934 { 935 const zio_t *z1 = x1; 936 const zio_t *z2 = x2; 937 938 if (z1->io_bookmark.zb_objset < z2->io_bookmark.zb_objset) 939 return (-1); 940 if (z1->io_bookmark.zb_objset > z2->io_bookmark.zb_objset) 941 return (1); 942 943 if (z1->io_bookmark.zb_object < z2->io_bookmark.zb_object) 944 return (-1); 945 if (z1->io_bookmark.zb_object > z2->io_bookmark.zb_object) 946 return (1); 947 948 if (z1->io_bookmark.zb_level < z2->io_bookmark.zb_level) 949 return (-1); 950 if (z1->io_bookmark.zb_level > z2->io_bookmark.zb_level) 951 return (1); 952 953 if (z1->io_bookmark.zb_blkid < z2->io_bookmark.zb_blkid) 954 return (-1); 955 if (z1->io_bookmark.zb_blkid > z2->io_bookmark.zb_blkid) 956 return (1); 957 958 if (z1 < z2) 959 return (-1); 960 if (z1 > z2) 961 return (1); 962 963 return (0); 964 } 965 966 /* 967 * ========================================================================== 968 * Create the various types of I/O (read, write, free, etc) 969 * ========================================================================== 970 */ 971 static zio_t * 972 zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, 973 abd_t *data, uint64_t lsize, uint64_t psize, zio_done_func_t *done, 974 void *private, zio_type_t type, zio_priority_t priority, 975 zio_flag_t flags, vdev_t *vd, uint64_t offset, 976 const zbookmark_phys_t *zb, enum zio_stage stage, 977 enum zio_stage pipeline) 978 { 979 zio_t *zio; 980 981 IMPLY(type != ZIO_TYPE_TRIM, psize <= SPA_MAXBLOCKSIZE); 982 ASSERT(P2PHASE(psize, SPA_MINBLOCKSIZE) == 0); 983 ASSERT(P2PHASE(offset, SPA_MINBLOCKSIZE) == 0); 984 985 ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER)); 986 ASSERT(!bp || !(flags & ZIO_FLAG_CONFIG_WRITER)); 987 ASSERT(vd || stage == ZIO_STAGE_OPEN); 988 989 IMPLY(lsize != psize, (flags & ZIO_FLAG_RAW_COMPRESS) != 0); 990 991 zio = kmem_cache_alloc(zio_cache, KM_SLEEP); 992 memset(zio, 0, sizeof (zio_t)); 993 994 mutex_init(&zio->io_lock, NULL, MUTEX_NOLOCKDEP, NULL); 995 cv_init(&zio->io_cv, NULL, CV_DEFAULT, NULL); 996 997 list_create(&zio->io_parent_list, sizeof (zio_link_t), 998 offsetof(zio_link_t, zl_parent_node)); 999 list_create(&zio->io_child_list, sizeof (zio_link_t), 1000 offsetof(zio_link_t, zl_child_node)); 1001 metaslab_trace_init(&zio->io_alloc_list); 1002 1003 if (vd != NULL) 1004 zio->io_child_type = ZIO_CHILD_VDEV; 1005 else if (flags & ZIO_FLAG_GANG_CHILD) 1006 zio->io_child_type = ZIO_CHILD_GANG; 1007 else if (flags & ZIO_FLAG_DDT_CHILD) 1008 zio->io_child_type = ZIO_CHILD_DDT; 1009 else 1010 zio->io_child_type = ZIO_CHILD_LOGICAL; 1011 1012 if (bp != NULL) { 1013 if (type != ZIO_TYPE_WRITE || 1014 zio->io_child_type == ZIO_CHILD_DDT) { 1015 zio->io_bp_copy = *bp; 1016 zio->io_bp = &zio->io_bp_copy; /* so caller can free */ 1017 } else { 1018 zio->io_bp = (blkptr_t *)bp; 1019 } 1020 zio->io_bp_orig = *bp; 1021 if (zio->io_child_type == ZIO_CHILD_LOGICAL) 1022 zio->io_logical = zio; 1023 if (zio->io_child_type > ZIO_CHILD_GANG && BP_IS_GANG(bp)) 1024 pipeline |= ZIO_GANG_STAGES; 1025 if (flags & ZIO_FLAG_PREALLOCATED) { 1026 BP_ZERO_DVAS(zio->io_bp); 1027 BP_SET_BIRTH(zio->io_bp, 0, 0); 1028 } 1029 } 1030 1031 zio->io_spa = spa; 1032 zio->io_txg = txg; 1033 zio->io_done = done; 1034 zio->io_private = private; 1035 zio->io_type = type; 1036 zio->io_priority = priority; 1037 zio->io_vd = vd; 1038 zio->io_offset = offset; 1039 zio->io_orig_abd = zio->io_abd = data; 1040 zio->io_orig_size = zio->io_size = psize; 1041 zio->io_lsize = lsize; 1042 zio->io_orig_flags = zio->io_flags = flags; 1043 zio->io_orig_stage = zio->io_stage = stage; 1044 zio->io_orig_pipeline = zio->io_pipeline = pipeline; 1045 zio->io_pipeline_trace = ZIO_STAGE_OPEN; 1046 zio->io_allocator = ZIO_ALLOCATOR_NONE; 1047 1048 zio->io_state[ZIO_WAIT_READY] = (stage >= ZIO_STAGE_READY) || 1049 (pipeline & ZIO_STAGE_READY) == 0; 1050 zio->io_state[ZIO_WAIT_DONE] = (stage >= ZIO_STAGE_DONE); 1051 1052 if (zb != NULL) 1053 zio->io_bookmark = *zb; 1054 1055 if (pio != NULL) { 1056 zio->io_metaslab_class = pio->io_metaslab_class; 1057 if (zio->io_logical == NULL) 1058 zio->io_logical = pio->io_logical; 1059 if (zio->io_child_type == ZIO_CHILD_GANG) 1060 zio->io_gang_leader = pio->io_gang_leader; 1061 zio_add_child_first(pio, zio); 1062 } 1063 1064 taskq_init_ent(&zio->io_tqent); 1065 1066 return (zio); 1067 } 1068 1069 void 1070 zio_destroy(zio_t *zio) 1071 { 1072 metaslab_trace_fini(&zio->io_alloc_list); 1073 list_destroy(&zio->io_parent_list); 1074 list_destroy(&zio->io_child_list); 1075 mutex_destroy(&zio->io_lock); 1076 cv_destroy(&zio->io_cv); 1077 kmem_cache_free(zio_cache, zio); 1078 } 1079 1080 /* 1081 * ZIO intended to be between others. Provides synchronization at READY 1082 * and DONE pipeline stages and calls the respective callbacks. 1083 */ 1084 zio_t * 1085 zio_null(zio_t *pio, spa_t *spa, vdev_t *vd, zio_done_func_t *done, 1086 void *private, zio_flag_t flags) 1087 { 1088 zio_t *zio; 1089 1090 zio = zio_create(pio, spa, 0, NULL, NULL, 0, 0, done, private, 1091 ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL, 1092 ZIO_STAGE_OPEN, ZIO_INTERLOCK_PIPELINE); 1093 1094 return (zio); 1095 } 1096 1097 /* 1098 * ZIO intended to be a root of a tree. Unlike null ZIO does not have a 1099 * READY pipeline stage (is ready on creation), so it should not be used 1100 * as child of any ZIO that may need waiting for grandchildren READY stage 1101 * (any other ZIO type). 1102 */ 1103 zio_t * 1104 zio_root(spa_t *spa, zio_done_func_t *done, void *private, zio_flag_t flags) 1105 { 1106 zio_t *zio; 1107 1108 zio = zio_create(NULL, spa, 0, NULL, NULL, 0, 0, done, private, 1109 ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, NULL, 0, NULL, 1110 ZIO_STAGE_OPEN, ZIO_ROOT_PIPELINE); 1111 1112 return (zio); 1113 } 1114 1115 static int 1116 zfs_blkptr_verify_log(spa_t *spa, const blkptr_t *bp, 1117 enum blk_verify_flag blk_verify, const char *fmt, ...) 1118 { 1119 va_list adx; 1120 char buf[256]; 1121 1122 va_start(adx, fmt); 1123 (void) vsnprintf(buf, sizeof (buf), fmt, adx); 1124 va_end(adx); 1125 1126 zfs_dbgmsg("bad blkptr at %px: " 1127 "DVA[0]=%#llx/%#llx " 1128 "DVA[1]=%#llx/%#llx " 1129 "DVA[2]=%#llx/%#llx " 1130 "prop=%#llx " 1131 "pad=%#llx,%#llx " 1132 "phys_birth=%#llx " 1133 "birth=%#llx " 1134 "fill=%#llx " 1135 "cksum=%#llx/%#llx/%#llx/%#llx", 1136 bp, 1137 (long long)bp->blk_dva[0].dva_word[0], 1138 (long long)bp->blk_dva[0].dva_word[1], 1139 (long long)bp->blk_dva[1].dva_word[0], 1140 (long long)bp->blk_dva[1].dva_word[1], 1141 (long long)bp->blk_dva[2].dva_word[0], 1142 (long long)bp->blk_dva[2].dva_word[1], 1143 (long long)bp->blk_prop, 1144 (long long)bp->blk_pad[0], 1145 (long long)bp->blk_pad[1], 1146 (long long)BP_GET_PHYSICAL_BIRTH(bp), 1147 (long long)BP_GET_LOGICAL_BIRTH(bp), 1148 (long long)bp->blk_fill, 1149 (long long)bp->blk_cksum.zc_word[0], 1150 (long long)bp->blk_cksum.zc_word[1], 1151 (long long)bp->blk_cksum.zc_word[2], 1152 (long long)bp->blk_cksum.zc_word[3]); 1153 switch (blk_verify) { 1154 case BLK_VERIFY_HALT: 1155 zfs_panic_recover("%s: %s", spa_name(spa), buf); 1156 break; 1157 case BLK_VERIFY_LOG: 1158 zfs_dbgmsg("%s: %s", spa_name(spa), buf); 1159 break; 1160 case BLK_VERIFY_ONLY: 1161 break; 1162 } 1163 1164 return (1); 1165 } 1166 1167 /* 1168 * Verify the block pointer fields contain reasonable values. This means 1169 * it only contains known object types, checksum/compression identifiers, 1170 * block sizes within the maximum allowed limits, valid DVAs, etc. 1171 * 1172 * If everything checks out 0 is returned. The zfs_blkptr_verify 1173 * argument controls the behavior when an invalid field is detected. 1174 * 1175 * Values for blk_verify_flag: 1176 * BLK_VERIFY_ONLY: evaluate the block 1177 * BLK_VERIFY_LOG: evaluate the block and log problems 1178 * BLK_VERIFY_HALT: call zfs_panic_recover on error 1179 * 1180 * Values for blk_config_flag: 1181 * BLK_CONFIG_HELD: caller holds SCL_VDEV for writer 1182 * BLK_CONFIG_NEEDED: caller holds no config lock, SCL_VDEV will be 1183 * obtained for reader 1184 * BLK_CONFIG_SKIP: skip checks which require SCL_VDEV, for better 1185 * performance 1186 */ 1187 int 1188 zfs_blkptr_verify(spa_t *spa, const blkptr_t *bp, 1189 enum blk_config_flag blk_config, enum blk_verify_flag blk_verify) 1190 { 1191 int errors = 0; 1192 1193 if (unlikely(!DMU_OT_IS_VALID(BP_GET_TYPE(bp)))) { 1194 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1195 "blkptr at %px has invalid TYPE %llu", 1196 bp, (longlong_t)BP_GET_TYPE(bp)); 1197 } 1198 if (unlikely(BP_GET_COMPRESS(bp) >= ZIO_COMPRESS_FUNCTIONS)) { 1199 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1200 "blkptr at %px has invalid COMPRESS %llu", 1201 bp, (longlong_t)BP_GET_COMPRESS(bp)); 1202 } 1203 if (unlikely(BP_GET_LSIZE(bp) > SPA_MAXBLOCKSIZE)) { 1204 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1205 "blkptr at %px has invalid LSIZE %llu", 1206 bp, (longlong_t)BP_GET_LSIZE(bp)); 1207 } 1208 if (BP_IS_EMBEDDED(bp)) { 1209 if (unlikely(BPE_GET_ETYPE(bp) >= NUM_BP_EMBEDDED_TYPES)) { 1210 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1211 "blkptr at %px has invalid ETYPE %llu", 1212 bp, (longlong_t)BPE_GET_ETYPE(bp)); 1213 } 1214 if (unlikely(BPE_GET_PSIZE(bp) > BPE_PAYLOAD_SIZE)) { 1215 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1216 "blkptr at %px has invalid PSIZE %llu", 1217 bp, (longlong_t)BPE_GET_PSIZE(bp)); 1218 } 1219 return (errors ? ECKSUM : 0); 1220 } else if (BP_IS_HOLE(bp)) { 1221 /* 1222 * Holes are allowed (expected, even) to have no DVAs, no 1223 * checksum, and no psize. 1224 */ 1225 return (errors ? ECKSUM : 0); 1226 } else if (unlikely(!DVA_IS_VALID(&bp->blk_dva[0]))) { 1227 /* Non-hole, non-embedded BPs _must_ have at least one DVA */ 1228 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1229 "blkptr at %px has no valid DVAs", bp); 1230 } 1231 if (unlikely(BP_GET_CHECKSUM(bp) >= ZIO_CHECKSUM_FUNCTIONS)) { 1232 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1233 "blkptr at %px has invalid CHECKSUM %llu", 1234 bp, (longlong_t)BP_GET_CHECKSUM(bp)); 1235 } 1236 if (unlikely(BP_GET_PSIZE(bp) > SPA_MAXBLOCKSIZE)) { 1237 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1238 "blkptr at %px has invalid PSIZE %llu", 1239 bp, (longlong_t)BP_GET_PSIZE(bp)); 1240 } 1241 1242 /* 1243 * Do not verify individual DVAs if the config is not trusted. This 1244 * will be done once the zio is executed in vdev_mirror_map_alloc. 1245 */ 1246 if (unlikely(!spa->spa_trust_config)) 1247 return (errors ? ECKSUM : 0); 1248 1249 switch (blk_config) { 1250 case BLK_CONFIG_HELD: 1251 ASSERT(spa_config_held(spa, SCL_VDEV, RW_WRITER)); 1252 break; 1253 case BLK_CONFIG_NEEDED: 1254 spa_config_enter(spa, SCL_VDEV, bp, RW_READER); 1255 break; 1256 case BLK_CONFIG_NEEDED_TRY: 1257 if (!spa_config_tryenter(spa, SCL_VDEV, bp, RW_READER)) 1258 return (EBUSY); 1259 break; 1260 case BLK_CONFIG_SKIP: 1261 return (errors ? ECKSUM : 0); 1262 default: 1263 panic("invalid blk_config %u", blk_config); 1264 } 1265 1266 /* 1267 * Pool-specific checks. 1268 * 1269 * Note: it would be nice to verify that the logical birth 1270 * and physical birth are not too large. However, 1271 * spa_freeze() allows the birth time of log blocks (and 1272 * dmu_sync()-ed blocks that are in the log) to be arbitrarily 1273 * large. 1274 */ 1275 for (int i = 0; i < BP_GET_NDVAS(bp); i++) { 1276 const dva_t *dva = &bp->blk_dva[i]; 1277 uint64_t vdevid = DVA_GET_VDEV(dva); 1278 1279 if (unlikely(vdevid >= spa->spa_root_vdev->vdev_children)) { 1280 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1281 "blkptr at %px DVA %u has invalid VDEV %llu", 1282 bp, i, (longlong_t)vdevid); 1283 continue; 1284 } 1285 vdev_t *vd = spa->spa_root_vdev->vdev_child[vdevid]; 1286 if (unlikely(vd == NULL)) { 1287 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1288 "blkptr at %px DVA %u has invalid VDEV %llu", 1289 bp, i, (longlong_t)vdevid); 1290 continue; 1291 } 1292 if (unlikely(vd->vdev_ops == &vdev_hole_ops)) { 1293 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1294 "blkptr at %px DVA %u has hole VDEV %llu", 1295 bp, i, (longlong_t)vdevid); 1296 continue; 1297 } 1298 if (vd->vdev_ops == &vdev_missing_ops) { 1299 /* 1300 * "missing" vdevs are valid during import, but we 1301 * don't have their detailed info (e.g. asize), so 1302 * we can't perform any more checks on them. 1303 */ 1304 continue; 1305 } 1306 uint64_t offset = DVA_GET_OFFSET(dva); 1307 uint64_t asize = DVA_GET_ASIZE(dva); 1308 if (DVA_GET_GANG(dva)) 1309 asize = vdev_gang_header_asize(vd); 1310 if (unlikely(offset + asize > vd->vdev_asize)) { 1311 errors += zfs_blkptr_verify_log(spa, bp, blk_verify, 1312 "blkptr at %px DVA %u has invalid OFFSET %llu", 1313 bp, i, (longlong_t)offset); 1314 } 1315 } 1316 if (blk_config == BLK_CONFIG_NEEDED || blk_config == 1317 BLK_CONFIG_NEEDED_TRY) 1318 spa_config_exit(spa, SCL_VDEV, bp); 1319 1320 return (errors ? ECKSUM : 0); 1321 } 1322 1323 boolean_t 1324 zfs_dva_valid(spa_t *spa, const dva_t *dva, const blkptr_t *bp) 1325 { 1326 (void) bp; 1327 uint64_t vdevid = DVA_GET_VDEV(dva); 1328 1329 if (vdevid >= spa->spa_root_vdev->vdev_children) 1330 return (B_FALSE); 1331 1332 vdev_t *vd = spa->spa_root_vdev->vdev_child[vdevid]; 1333 if (vd == NULL) 1334 return (B_FALSE); 1335 1336 if (vd->vdev_ops == &vdev_hole_ops) 1337 return (B_FALSE); 1338 1339 if (vd->vdev_ops == &vdev_missing_ops) { 1340 return (B_FALSE); 1341 } 1342 1343 uint64_t offset = DVA_GET_OFFSET(dva); 1344 uint64_t asize = DVA_GET_ASIZE(dva); 1345 1346 if (DVA_GET_GANG(dva)) 1347 asize = vdev_gang_header_asize(vd); 1348 if (offset + asize > vd->vdev_asize) 1349 return (B_FALSE); 1350 1351 return (B_TRUE); 1352 } 1353 1354 zio_t * 1355 zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, 1356 abd_t *data, uint64_t size, zio_done_func_t *done, void *private, 1357 zio_priority_t priority, zio_flag_t flags, const zbookmark_phys_t *zb) 1358 { 1359 zio_t *zio; 1360 1361 zio = zio_create(pio, spa, BP_GET_BIRTH(bp), bp, 1362 data, size, size, done, private, 1363 ZIO_TYPE_READ, priority, flags, NULL, 0, zb, 1364 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ? 1365 ZIO_DDT_CHILD_READ_PIPELINE : ZIO_READ_PIPELINE); 1366 1367 return (zio); 1368 } 1369 1370 zio_t * 1371 zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, 1372 abd_t *data, uint64_t lsize, uint64_t psize, const zio_prop_t *zp, 1373 zio_done_func_t *ready, zio_done_func_t *children_ready, 1374 zio_done_func_t *done, void *private, zio_priority_t priority, 1375 zio_flag_t flags, const zbookmark_phys_t *zb) 1376 { 1377 zio_t *zio; 1378 enum zio_stage pipeline = zp->zp_direct_write == B_TRUE ? 1379 ZIO_DIRECT_WRITE_PIPELINE : (flags & ZIO_FLAG_DDT_CHILD) ? 1380 ZIO_DDT_CHILD_WRITE_PIPELINE : ZIO_WRITE_PIPELINE; 1381 1382 1383 zio = zio_create(pio, spa, txg, bp, data, lsize, psize, done, private, 1384 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb, 1385 ZIO_STAGE_OPEN, pipeline); 1386 1387 zio->io_ready = ready; 1388 zio->io_children_ready = children_ready; 1389 zio->io_prop = *zp; 1390 1391 /* 1392 * Data can be NULL if we are going to call zio_write_override() to 1393 * provide the already-allocated BP. But we may need the data to 1394 * verify a dedup hit (if requested). In this case, don't try to 1395 * dedup (just take the already-allocated BP verbatim). Encrypted 1396 * dedup blocks need data as well so we also disable dedup in this 1397 * case. 1398 */ 1399 if (data == NULL && 1400 (zio->io_prop.zp_dedup_verify || zio->io_prop.zp_encrypt)) { 1401 zio->io_prop.zp_dedup = zio->io_prop.zp_dedup_verify = B_FALSE; 1402 } 1403 1404 return (zio); 1405 } 1406 1407 zio_t * 1408 zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, abd_t *data, 1409 uint64_t size, zio_done_func_t *done, void *private, 1410 zio_priority_t priority, zio_flag_t flags, zbookmark_phys_t *zb) 1411 { 1412 zio_t *zio; 1413 1414 zio = zio_create(pio, spa, txg, bp, data, size, size, done, private, 1415 ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_IO_REWRITE, NULL, 0, zb, 1416 ZIO_STAGE_OPEN, ZIO_REWRITE_PIPELINE); 1417 1418 return (zio); 1419 } 1420 1421 void 1422 zio_write_override(zio_t *zio, blkptr_t *bp, int copies, int gang_copies, 1423 boolean_t nopwrite, boolean_t brtwrite) 1424 { 1425 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 1426 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 1427 ASSERT(zio->io_stage == ZIO_STAGE_OPEN); 1428 ASSERT(zio->io_txg == spa_syncing_txg(zio->io_spa)); 1429 ASSERT(!brtwrite || !nopwrite); 1430 1431 /* 1432 * We must reset the io_prop to match the values that existed 1433 * when the bp was first written by dmu_sync() keeping in mind 1434 * that nopwrite and dedup are mutually exclusive. 1435 */ 1436 zio->io_prop.zp_dedup = nopwrite ? B_FALSE : zio->io_prop.zp_dedup; 1437 zio->io_prop.zp_nopwrite = nopwrite; 1438 zio->io_prop.zp_brtwrite = brtwrite; 1439 zio->io_prop.zp_copies = copies; 1440 zio->io_prop.zp_gang_copies = gang_copies; 1441 zio->io_bp_override = bp; 1442 } 1443 1444 void 1445 zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp) 1446 { 1447 1448 (void) zfs_blkptr_verify(spa, bp, BLK_CONFIG_NEEDED, BLK_VERIFY_HALT); 1449 1450 /* 1451 * The check for EMBEDDED is a performance optimization. We 1452 * process the free here (by ignoring it) rather than 1453 * putting it on the list and then processing it in zio_free_sync(). 1454 */ 1455 if (BP_IS_EMBEDDED(bp)) 1456 return; 1457 1458 /* 1459 * Frees that are for the currently-syncing txg, are not going to be 1460 * deferred, and which will not need to do a read (i.e. not GANG or 1461 * DEDUP), can be processed immediately. Otherwise, put them on the 1462 * in-memory list for later processing. 1463 * 1464 * Note that we only defer frees after zfs_sync_pass_deferred_free 1465 * when the log space map feature is disabled. [see relevant comment 1466 * in spa_sync_iterate_to_convergence()] 1467 */ 1468 if (BP_IS_GANG(bp) || 1469 BP_GET_DEDUP(bp) || 1470 txg != spa->spa_syncing_txg || 1471 (spa_sync_pass(spa) >= zfs_sync_pass_deferred_free && 1472 !spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP)) || 1473 brt_maybe_exists(spa, bp)) { 1474 metaslab_check_free(spa, bp); 1475 bplist_append(&spa->spa_free_bplist[txg & TXG_MASK], bp); 1476 } else { 1477 VERIFY3P(zio_free_sync(NULL, spa, txg, bp, 0), ==, NULL); 1478 } 1479 } 1480 1481 /* 1482 * To improve performance, this function may return NULL if we were able 1483 * to do the free immediately. This avoids the cost of creating a zio 1484 * (and linking it to the parent, etc). 1485 */ 1486 zio_t * 1487 zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, 1488 zio_flag_t flags) 1489 { 1490 ASSERT(!BP_IS_HOLE(bp)); 1491 ASSERT(spa_syncing_txg(spa) == txg); 1492 1493 if (BP_IS_EMBEDDED(bp)) 1494 return (NULL); 1495 1496 metaslab_check_free(spa, bp); 1497 arc_freed(spa, bp); 1498 dsl_scan_freed(spa, bp); 1499 1500 if (BP_IS_GANG(bp) || 1501 BP_GET_DEDUP(bp) || 1502 brt_maybe_exists(spa, bp)) { 1503 /* 1504 * GANG, DEDUP and BRT blocks can induce a read (for the gang 1505 * block header, the DDT or the BRT), so issue them 1506 * asynchronously so that this thread is not tied up. 1507 */ 1508 enum zio_stage stage = 1509 ZIO_FREE_PIPELINE | ZIO_STAGE_ISSUE_ASYNC; 1510 1511 return (zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp), 1512 BP_GET_PSIZE(bp), NULL, NULL, 1513 ZIO_TYPE_FREE, ZIO_PRIORITY_NOW, 1514 flags, NULL, 0, NULL, ZIO_STAGE_OPEN, stage)); 1515 } else { 1516 metaslab_free(spa, bp, txg, B_FALSE); 1517 return (NULL); 1518 } 1519 } 1520 1521 zio_t * 1522 zio_claim(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp, 1523 zio_done_func_t *done, void *private, zio_flag_t flags) 1524 { 1525 zio_t *zio; 1526 1527 (void) zfs_blkptr_verify(spa, bp, (flags & ZIO_FLAG_CONFIG_WRITER) ? 1528 BLK_CONFIG_HELD : BLK_CONFIG_NEEDED, BLK_VERIFY_HALT); 1529 1530 if (BP_IS_EMBEDDED(bp)) 1531 return (zio_null(pio, spa, NULL, NULL, NULL, 0)); 1532 1533 /* 1534 * A claim is an allocation of a specific block. Claims are needed 1535 * to support immediate writes in the intent log. The issue is that 1536 * immediate writes contain committed data, but in a txg that was 1537 * *not* committed. Upon opening the pool after an unclean shutdown, 1538 * the intent log claims all blocks that contain immediate write data 1539 * so that the SPA knows they're in use. 1540 * 1541 * All claims *must* be resolved in the first txg -- before the SPA 1542 * starts allocating blocks -- so that nothing is allocated twice. 1543 * If txg == 0 we just verify that the block is claimable. 1544 */ 1545 ASSERT3U(BP_GET_LOGICAL_BIRTH(&spa->spa_uberblock.ub_rootbp), <, 1546 spa_min_claim_txg(spa)); 1547 ASSERT(txg == spa_min_claim_txg(spa) || txg == 0); 1548 ASSERT(!BP_GET_DEDUP(bp) || !spa_writeable(spa)); /* zdb(8) */ 1549 1550 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp), 1551 BP_GET_PSIZE(bp), done, private, ZIO_TYPE_CLAIM, ZIO_PRIORITY_NOW, 1552 flags, NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_CLAIM_PIPELINE); 1553 ASSERT0(zio->io_queued_timestamp); 1554 1555 return (zio); 1556 } 1557 1558 zio_t * 1559 zio_trim(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, 1560 zio_done_func_t *done, void *private, zio_priority_t priority, 1561 zio_flag_t flags, enum trim_flag trim_flags) 1562 { 1563 zio_t *zio; 1564 1565 ASSERT0(vd->vdev_children); 1566 ASSERT0(P2PHASE(offset, 1ULL << vd->vdev_ashift)); 1567 ASSERT0(P2PHASE(size, 1ULL << vd->vdev_ashift)); 1568 ASSERT3U(size, !=, 0); 1569 1570 zio = zio_create(pio, vd->vdev_spa, 0, NULL, NULL, size, size, done, 1571 private, ZIO_TYPE_TRIM, priority, flags | ZIO_FLAG_PHYSICAL, 1572 vd, offset, NULL, ZIO_STAGE_OPEN, ZIO_TRIM_PIPELINE); 1573 zio->io_trim_flags = trim_flags; 1574 1575 return (zio); 1576 } 1577 1578 zio_t * 1579 zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, 1580 abd_t *data, int checksum, zio_done_func_t *done, void *private, 1581 zio_priority_t priority, zio_flag_t flags, boolean_t labels) 1582 { 1583 zio_t *zio; 1584 1585 ASSERT(vd->vdev_children == 0); 1586 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE || 1587 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE); 1588 ASSERT3U(offset + size, <=, vd->vdev_psize); 1589 1590 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, size, done, 1591 private, ZIO_TYPE_READ, priority, flags | ZIO_FLAG_PHYSICAL, vd, 1592 offset, NULL, ZIO_STAGE_OPEN, ZIO_READ_PHYS_PIPELINE); 1593 1594 zio->io_prop.zp_checksum = checksum; 1595 1596 return (zio); 1597 } 1598 1599 zio_t * 1600 zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size, 1601 abd_t *data, int checksum, zio_done_func_t *done, void *private, 1602 zio_priority_t priority, zio_flag_t flags, boolean_t labels) 1603 { 1604 zio_t *zio; 1605 1606 ASSERT(vd->vdev_children == 0); 1607 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE || 1608 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE); 1609 ASSERT3U(offset + size, <=, vd->vdev_psize); 1610 1611 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, size, done, 1612 private, ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_PHYSICAL, vd, 1613 offset, NULL, ZIO_STAGE_OPEN, ZIO_WRITE_PHYS_PIPELINE); 1614 1615 zio->io_prop.zp_checksum = checksum; 1616 1617 if (zio_checksum_table[checksum].ci_flags & ZCHECKSUM_FLAG_EMBEDDED) { 1618 /* 1619 * zec checksums are necessarily destructive -- they modify 1620 * the end of the write buffer to hold the verifier/checksum. 1621 * Therefore, we must make a local copy in case the data is 1622 * being written to multiple places in parallel. 1623 */ 1624 abd_t *wbuf = abd_alloc_sametype(data, size); 1625 abd_copy(wbuf, data, size); 1626 1627 zio_push_transform(zio, wbuf, size, size, NULL); 1628 } 1629 1630 return (zio); 1631 } 1632 1633 /* 1634 * Create a child I/O to do some work for us. 1635 */ 1636 zio_t * 1637 zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset, 1638 abd_t *data, uint64_t size, int type, zio_priority_t priority, 1639 zio_flag_t flags, zio_done_func_t *done, void *private) 1640 { 1641 enum zio_stage pipeline = ZIO_VDEV_CHILD_PIPELINE; 1642 zio_t *zio; 1643 1644 /* 1645 * vdev child I/Os do not propagate their error to the parent. 1646 * Therefore, for correct operation the caller *must* check for 1647 * and handle the error in the child i/o's done callback. 1648 * The only exceptions are i/os that we don't care about 1649 * (OPTIONAL or REPAIR). 1650 */ 1651 ASSERT((flags & ZIO_FLAG_OPTIONAL) || (flags & ZIO_FLAG_IO_REPAIR) || 1652 done != NULL); 1653 1654 if (type == ZIO_TYPE_READ && bp != NULL) { 1655 /* 1656 * If we have the bp, then the child should perform the 1657 * checksum and the parent need not. This pushes error 1658 * detection as close to the leaves as possible and 1659 * eliminates redundant checksums in the interior nodes. 1660 */ 1661 pipeline |= ZIO_STAGE_CHECKSUM_VERIFY; 1662 pio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY; 1663 /* 1664 * We never allow the mirror VDEV to attempt reading from any 1665 * additional data copies after the first Direct I/O checksum 1666 * verify failure. This is to avoid bad data being written out 1667 * through the mirror during self healing. See comment in 1668 * vdev_mirror_io_done() for more details. 1669 */ 1670 ASSERT0(pio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR); 1671 } else if (type == ZIO_TYPE_WRITE && 1672 pio->io_prop.zp_direct_write == B_TRUE) { 1673 /* 1674 * By default we only will verify checksums for Direct I/O 1675 * writes for Linux. FreeBSD is able to place user pages under 1676 * write protection before issuing them to the ZIO pipeline. 1677 * 1678 * Checksum validation errors will only be reported through 1679 * the top-level VDEV, which is set by this child ZIO. 1680 */ 1681 ASSERT3P(bp, !=, NULL); 1682 ASSERT3U(pio->io_child_type, ==, ZIO_CHILD_LOGICAL); 1683 pipeline |= ZIO_STAGE_DIO_CHECKSUM_VERIFY; 1684 } 1685 1686 if (vd->vdev_ops->vdev_op_leaf) { 1687 ASSERT0(vd->vdev_children); 1688 offset += VDEV_LABEL_START_SIZE; 1689 } 1690 1691 flags |= ZIO_VDEV_CHILD_FLAGS(pio); 1692 1693 /* 1694 * If we've decided to do a repair, the write is not speculative -- 1695 * even if the original read was. 1696 */ 1697 if (flags & ZIO_FLAG_IO_REPAIR) 1698 flags &= ~ZIO_FLAG_SPECULATIVE; 1699 1700 /* 1701 * If we're creating a child I/O that is not associated with a 1702 * top-level vdev, then the child zio is not an allocating I/O. 1703 * If this is a retried I/O then we ignore it since we will 1704 * have already processed the original allocating I/O. 1705 */ 1706 if (flags & ZIO_FLAG_IO_ALLOCATING && 1707 (vd != vd->vdev_top || (flags & ZIO_FLAG_IO_RETRY))) { 1708 ASSERT(pio->io_metaslab_class != NULL); 1709 ASSERT(pio->io_metaslab_class->mc_alloc_throttle_enabled); 1710 ASSERT(type == ZIO_TYPE_WRITE); 1711 ASSERT(priority == ZIO_PRIORITY_ASYNC_WRITE); 1712 ASSERT(!(flags & ZIO_FLAG_IO_REPAIR)); 1713 ASSERT(!(pio->io_flags & ZIO_FLAG_IO_REWRITE) || 1714 pio->io_child_type == ZIO_CHILD_GANG); 1715 1716 flags &= ~ZIO_FLAG_IO_ALLOCATING; 1717 } 1718 1719 zio = zio_create(pio, pio->io_spa, pio->io_txg, bp, data, size, size, 1720 done, private, type, priority, flags, vd, offset, &pio->io_bookmark, 1721 ZIO_STAGE_VDEV_IO_START >> 1, pipeline); 1722 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV); 1723 1724 return (zio); 1725 } 1726 1727 zio_t * 1728 zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, abd_t *data, uint64_t size, 1729 zio_type_t type, zio_priority_t priority, zio_flag_t flags, 1730 zio_done_func_t *done, void *private) 1731 { 1732 zio_t *zio; 1733 1734 ASSERT(vd->vdev_ops->vdev_op_leaf); 1735 1736 zio = zio_create(NULL, vd->vdev_spa, 0, NULL, 1737 data, size, size, done, private, type, priority, 1738 flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY | ZIO_FLAG_DELEGATED, 1739 vd, offset, NULL, 1740 ZIO_STAGE_VDEV_IO_START >> 1, ZIO_VDEV_CHILD_PIPELINE); 1741 1742 return (zio); 1743 } 1744 1745 1746 /* 1747 * Send a flush command to the given vdev. Unlike most zio creation functions, 1748 * the flush zios are issued immediately. You can wait on pio to pause until 1749 * the flushes complete. 1750 */ 1751 void 1752 zio_flush(zio_t *pio, vdev_t *vd) 1753 { 1754 const zio_flag_t flags = ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | 1755 ZIO_FLAG_DONT_RETRY; 1756 1757 if (vd->vdev_nowritecache) 1758 return; 1759 1760 if (vd->vdev_children == 0) { 1761 zio_nowait(zio_create(pio, vd->vdev_spa, 0, NULL, NULL, 0, 0, 1762 NULL, NULL, ZIO_TYPE_FLUSH, ZIO_PRIORITY_NOW, flags, vd, 0, 1763 NULL, ZIO_STAGE_OPEN, ZIO_FLUSH_PIPELINE)); 1764 } else { 1765 for (uint64_t c = 0; c < vd->vdev_children; c++) 1766 zio_flush(pio, vd->vdev_child[c]); 1767 } 1768 } 1769 1770 void 1771 zio_shrink(zio_t *zio, uint64_t size) 1772 { 1773 ASSERT3P(zio->io_executor, ==, NULL); 1774 ASSERT3U(zio->io_orig_size, ==, zio->io_size); 1775 ASSERT3U(size, <=, zio->io_size); 1776 1777 /* 1778 * We don't shrink for raidz because of problems with the 1779 * reconstruction when reading back less than the block size. 1780 * Note, BP_IS_RAIDZ() assumes no compression. 1781 */ 1782 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); 1783 if (!BP_IS_RAIDZ(zio->io_bp)) { 1784 /* we are not doing a raw write */ 1785 ASSERT3U(zio->io_size, ==, zio->io_lsize); 1786 zio->io_orig_size = zio->io_size = zio->io_lsize = size; 1787 } 1788 } 1789 1790 /* 1791 * Round provided allocation size up to a value that can be allocated 1792 * by at least some vdev(s) in the pool with minimum or no additional 1793 * padding and without extra space usage on others 1794 */ 1795 static uint64_t 1796 zio_roundup_alloc_size(spa_t *spa, uint64_t size) 1797 { 1798 if (size > spa->spa_min_alloc) 1799 return (roundup(size, spa->spa_gcd_alloc)); 1800 return (spa->spa_min_alloc); 1801 } 1802 1803 size_t 1804 zio_get_compression_max_size(enum zio_compress compress, uint64_t gcd_alloc, 1805 uint64_t min_alloc, size_t s_len) 1806 { 1807 size_t d_len; 1808 1809 /* minimum 12.5% must be saved (legacy value, may be changed later) */ 1810 d_len = s_len - (s_len >> 3); 1811 1812 /* ZLE can't use exactly d_len bytes, it needs more, so ignore it */ 1813 if (compress == ZIO_COMPRESS_ZLE) 1814 return (d_len); 1815 1816 d_len = d_len - d_len % gcd_alloc; 1817 1818 if (d_len < min_alloc) 1819 return (BPE_PAYLOAD_SIZE); 1820 return (d_len); 1821 } 1822 1823 /* 1824 * ========================================================================== 1825 * Prepare to read and write logical blocks 1826 * ========================================================================== 1827 */ 1828 1829 static zio_t * 1830 zio_read_bp_init(zio_t *zio) 1831 { 1832 blkptr_t *bp = zio->io_bp; 1833 uint64_t psize = 1834 BP_IS_EMBEDDED(bp) ? BPE_GET_PSIZE(bp) : BP_GET_PSIZE(bp); 1835 1836 ASSERT3P(zio->io_bp, ==, &zio->io_bp_copy); 1837 1838 if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF && 1839 zio->io_child_type == ZIO_CHILD_LOGICAL && 1840 !(zio->io_flags & ZIO_FLAG_RAW_COMPRESS)) { 1841 zio_push_transform(zio, abd_alloc_sametype(zio->io_abd, psize), 1842 psize, psize, zio_decompress); 1843 } 1844 1845 if (((BP_IS_PROTECTED(bp) && !(zio->io_flags & ZIO_FLAG_RAW_ENCRYPT)) || 1846 BP_HAS_INDIRECT_MAC_CKSUM(bp)) && 1847 zio->io_child_type == ZIO_CHILD_LOGICAL) { 1848 zio_push_transform(zio, abd_alloc_sametype(zio->io_abd, psize), 1849 psize, psize, zio_decrypt); 1850 } 1851 1852 if (BP_IS_EMBEDDED(bp) && BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA) { 1853 int psize = BPE_GET_PSIZE(bp); 1854 void *data = abd_borrow_buf(zio->io_abd, psize); 1855 1856 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1857 decode_embedded_bp_compressed(bp, data); 1858 abd_return_buf_copy(zio->io_abd, data, psize); 1859 } else { 1860 ASSERT(!BP_IS_EMBEDDED(bp)); 1861 } 1862 1863 if (BP_GET_DEDUP(bp) && zio->io_child_type == ZIO_CHILD_LOGICAL) 1864 zio->io_pipeline = ZIO_DDT_READ_PIPELINE; 1865 1866 return (zio); 1867 } 1868 1869 static zio_t * 1870 zio_write_bp_init(zio_t *zio) 1871 { 1872 if (!IO_IS_ALLOCATING(zio)) 1873 return (zio); 1874 1875 ASSERT(zio->io_child_type != ZIO_CHILD_DDT); 1876 1877 if (zio->io_bp_override) { 1878 blkptr_t *bp = zio->io_bp; 1879 zio_prop_t *zp = &zio->io_prop; 1880 1881 ASSERT(BP_GET_LOGICAL_BIRTH(bp) != zio->io_txg); 1882 1883 *bp = *zio->io_bp_override; 1884 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1885 1886 if (zp->zp_brtwrite) 1887 return (zio); 1888 1889 ASSERT(!BP_GET_DEDUP(zio->io_bp_override)); 1890 1891 if (BP_IS_EMBEDDED(bp)) 1892 return (zio); 1893 1894 /* 1895 * If we've been overridden and nopwrite is set then 1896 * set the flag accordingly to indicate that a nopwrite 1897 * has already occurred. 1898 */ 1899 if (!BP_IS_HOLE(bp) && zp->zp_nopwrite) { 1900 ASSERT(!zp->zp_dedup); 1901 ASSERT3U(BP_GET_CHECKSUM(bp), ==, zp->zp_checksum); 1902 zio->io_flags |= ZIO_FLAG_NOPWRITE; 1903 return (zio); 1904 } 1905 1906 ASSERT(!zp->zp_nopwrite); 1907 1908 if (BP_IS_HOLE(bp) || !zp->zp_dedup) 1909 return (zio); 1910 1911 ASSERT((zio_checksum_table[zp->zp_checksum].ci_flags & 1912 ZCHECKSUM_FLAG_DEDUP) || zp->zp_dedup_verify); 1913 1914 if (BP_GET_CHECKSUM(bp) == zp->zp_checksum && 1915 !zp->zp_encrypt) { 1916 BP_SET_DEDUP(bp, 1); 1917 zio->io_pipeline |= ZIO_STAGE_DDT_WRITE; 1918 return (zio); 1919 } 1920 1921 /* 1922 * We were unable to handle this as an override bp, treat 1923 * it as a regular write I/O. 1924 */ 1925 zio->io_bp_override = NULL; 1926 *bp = zio->io_bp_orig; 1927 zio->io_pipeline = zio->io_orig_pipeline; 1928 } 1929 1930 return (zio); 1931 } 1932 1933 static zio_t * 1934 zio_write_compress(zio_t *zio) 1935 { 1936 spa_t *spa = zio->io_spa; 1937 zio_prop_t *zp = &zio->io_prop; 1938 enum zio_compress compress = zp->zp_compress; 1939 blkptr_t *bp = zio->io_bp; 1940 uint64_t lsize = zio->io_lsize; 1941 uint64_t psize = zio->io_size; 1942 uint32_t pass = 1; 1943 1944 /* 1945 * If our children haven't all reached the ready stage, 1946 * wait for them and then repeat this pipeline stage. 1947 */ 1948 if (zio_wait_for_children(zio, ZIO_CHILD_LOGICAL_BIT | 1949 ZIO_CHILD_GANG_BIT, ZIO_WAIT_READY)) { 1950 return (NULL); 1951 } 1952 1953 if (!IO_IS_ALLOCATING(zio)) 1954 return (zio); 1955 1956 if (zio->io_children_ready != NULL) { 1957 /* 1958 * Now that all our children are ready, run the callback 1959 * associated with this zio in case it wants to modify the 1960 * data to be written. 1961 */ 1962 ASSERT3U(zp->zp_level, >, 0); 1963 zio->io_children_ready(zio); 1964 } 1965 1966 ASSERT(zio->io_child_type != ZIO_CHILD_DDT); 1967 ASSERT(zio->io_bp_override == NULL); 1968 1969 if (!BP_IS_HOLE(bp) && BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg) { 1970 /* 1971 * We're rewriting an existing block, which means we're 1972 * working on behalf of spa_sync(). For spa_sync() to 1973 * converge, it must eventually be the case that we don't 1974 * have to allocate new blocks. But compression changes 1975 * the blocksize, which forces a reallocate, and makes 1976 * convergence take longer. Therefore, after the first 1977 * few passes, stop compressing to ensure convergence. 1978 */ 1979 pass = spa_sync_pass(spa); 1980 1981 ASSERT(zio->io_txg == spa_syncing_txg(spa)); 1982 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 1983 ASSERT(!BP_GET_DEDUP(bp)); 1984 1985 if (pass >= zfs_sync_pass_dont_compress) 1986 compress = ZIO_COMPRESS_OFF; 1987 1988 /* Make sure someone doesn't change their mind on overwrites */ 1989 ASSERT(BP_IS_EMBEDDED(bp) || BP_IS_GANG(bp) || 1990 MIN(zp->zp_copies, spa_max_replication(spa)) 1991 == BP_GET_NDVAS(bp)); 1992 } 1993 1994 /* If it's a compressed write that is not raw, compress the buffer. */ 1995 if (compress != ZIO_COMPRESS_OFF && 1996 !(zio->io_flags & ZIO_FLAG_RAW_COMPRESS)) { 1997 abd_t *cabd = NULL; 1998 if (abd_cmp_zero(zio->io_abd, lsize) == 0) 1999 psize = 0; 2000 else if (compress == ZIO_COMPRESS_EMPTY) 2001 psize = lsize; 2002 else 2003 psize = zio_compress_data(compress, zio->io_abd, &cabd, 2004 lsize, 2005 zio_get_compression_max_size(compress, 2006 spa->spa_gcd_alloc, spa->spa_min_alloc, lsize), 2007 zp->zp_complevel); 2008 if (psize == 0) { 2009 compress = ZIO_COMPRESS_OFF; 2010 } else if (psize >= lsize) { 2011 compress = ZIO_COMPRESS_OFF; 2012 if (cabd != NULL) 2013 abd_free(cabd); 2014 } else if (psize <= BPE_PAYLOAD_SIZE && !zp->zp_encrypt && 2015 zp->zp_level == 0 && !DMU_OT_HAS_FILL(zp->zp_type) && 2016 spa_feature_is_enabled(spa, SPA_FEATURE_EMBEDDED_DATA)) { 2017 void *cbuf = abd_borrow_buf_copy(cabd, lsize); 2018 encode_embedded_bp_compressed(bp, 2019 cbuf, compress, lsize, psize); 2020 BPE_SET_ETYPE(bp, BP_EMBEDDED_TYPE_DATA); 2021 BP_SET_TYPE(bp, zio->io_prop.zp_type); 2022 BP_SET_LEVEL(bp, zio->io_prop.zp_level); 2023 abd_return_buf(cabd, cbuf, lsize); 2024 abd_free(cabd); 2025 BP_SET_LOGICAL_BIRTH(bp, zio->io_txg); 2026 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 2027 ASSERT(spa_feature_is_active(spa, 2028 SPA_FEATURE_EMBEDDED_DATA)); 2029 return (zio); 2030 } else { 2031 /* 2032 * Round compressed size up to the minimum allocation 2033 * size of the smallest-ashift device, and zero the 2034 * tail. This ensures that the compressed size of the 2035 * BP (and thus compressratio property) are correct, 2036 * in that we charge for the padding used to fill out 2037 * the last sector. 2038 */ 2039 size_t rounded = (size_t)zio_roundup_alloc_size(spa, 2040 psize); 2041 if (rounded >= lsize) { 2042 compress = ZIO_COMPRESS_OFF; 2043 abd_free(cabd); 2044 psize = lsize; 2045 } else { 2046 abd_zero_off(cabd, psize, rounded - psize); 2047 psize = rounded; 2048 zio_push_transform(zio, cabd, 2049 psize, lsize, NULL); 2050 } 2051 } 2052 2053 /* 2054 * We were unable to handle this as an override bp, treat 2055 * it as a regular write I/O. 2056 */ 2057 zio->io_bp_override = NULL; 2058 *bp = zio->io_bp_orig; 2059 zio->io_pipeline = zio->io_orig_pipeline; 2060 2061 } else if ((zio->io_flags & ZIO_FLAG_RAW_ENCRYPT) != 0 && 2062 zp->zp_type == DMU_OT_DNODE) { 2063 /* 2064 * The DMU actually relies on the zio layer's compression 2065 * to free metadnode blocks that have had all contained 2066 * dnodes freed. As a result, even when doing a raw 2067 * receive, we must check whether the block can be compressed 2068 * to a hole. 2069 */ 2070 if (abd_cmp_zero(zio->io_abd, lsize) == 0) { 2071 psize = 0; 2072 compress = ZIO_COMPRESS_OFF; 2073 } else { 2074 psize = lsize; 2075 } 2076 } else if (zio->io_flags & ZIO_FLAG_RAW_COMPRESS && 2077 !(zio->io_flags & ZIO_FLAG_RAW_ENCRYPT)) { 2078 /* 2079 * If we are raw receiving an encrypted dataset we should not 2080 * take this codepath because it will change the on-disk block 2081 * and decryption will fail. 2082 */ 2083 size_t rounded = MIN((size_t)zio_roundup_alloc_size(spa, psize), 2084 lsize); 2085 2086 if (rounded != psize) { 2087 abd_t *cdata = abd_alloc_linear(rounded, B_TRUE); 2088 abd_zero_off(cdata, psize, rounded - psize); 2089 abd_copy_off(cdata, zio->io_abd, 0, 0, psize); 2090 psize = rounded; 2091 zio_push_transform(zio, cdata, 2092 psize, rounded, NULL); 2093 } 2094 } else { 2095 ASSERT3U(psize, !=, 0); 2096 } 2097 2098 /* 2099 * The final pass of spa_sync() must be all rewrites, but the first 2100 * few passes offer a trade-off: allocating blocks defers convergence, 2101 * but newly allocated blocks are sequential, so they can be written 2102 * to disk faster. Therefore, we allow the first few passes of 2103 * spa_sync() to allocate new blocks, but force rewrites after that. 2104 * There should only be a handful of blocks after pass 1 in any case. 2105 */ 2106 if (!BP_IS_HOLE(bp) && BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg && 2107 BP_GET_PSIZE(bp) == psize && 2108 pass >= zfs_sync_pass_rewrite) { 2109 VERIFY3U(psize, !=, 0); 2110 enum zio_stage gang_stages = zio->io_pipeline & ZIO_GANG_STAGES; 2111 2112 zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages; 2113 zio->io_flags |= ZIO_FLAG_IO_REWRITE; 2114 } else { 2115 BP_ZERO(bp); 2116 zio->io_pipeline = ZIO_WRITE_PIPELINE; 2117 } 2118 2119 if (psize == 0) { 2120 if (BP_GET_LOGICAL_BIRTH(&zio->io_bp_orig) != 0 && 2121 spa_feature_is_active(spa, SPA_FEATURE_HOLE_BIRTH)) { 2122 BP_SET_LSIZE(bp, lsize); 2123 BP_SET_TYPE(bp, zp->zp_type); 2124 BP_SET_LEVEL(bp, zp->zp_level); 2125 BP_SET_BIRTH(bp, zio->io_txg, 0); 2126 } 2127 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 2128 } else { 2129 ASSERT(zp->zp_checksum != ZIO_CHECKSUM_GANG_HEADER); 2130 BP_SET_LSIZE(bp, lsize); 2131 BP_SET_TYPE(bp, zp->zp_type); 2132 BP_SET_LEVEL(bp, zp->zp_level); 2133 BP_SET_PSIZE(bp, psize); 2134 BP_SET_COMPRESS(bp, compress); 2135 BP_SET_CHECKSUM(bp, zp->zp_checksum); 2136 BP_SET_DEDUP(bp, zp->zp_dedup); 2137 BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER); 2138 if (zp->zp_dedup) { 2139 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2140 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 2141 ASSERT(!zp->zp_encrypt || 2142 DMU_OT_IS_ENCRYPTED(zp->zp_type)); 2143 zio->io_pipeline = ZIO_DDT_WRITE_PIPELINE; 2144 } 2145 if (zp->zp_nopwrite) { 2146 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2147 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 2148 zio->io_pipeline |= ZIO_STAGE_NOP_WRITE; 2149 } 2150 } 2151 return (zio); 2152 } 2153 2154 static zio_t * 2155 zio_free_bp_init(zio_t *zio) 2156 { 2157 blkptr_t *bp = zio->io_bp; 2158 2159 if (zio->io_child_type == ZIO_CHILD_LOGICAL) { 2160 if (BP_GET_DEDUP(bp)) 2161 zio->io_pipeline = ZIO_DDT_FREE_PIPELINE; 2162 } 2163 2164 ASSERT3P(zio->io_bp, ==, &zio->io_bp_copy); 2165 2166 return (zio); 2167 } 2168 2169 /* 2170 * ========================================================================== 2171 * Execute the I/O pipeline 2172 * ========================================================================== 2173 */ 2174 2175 static void 2176 zio_taskq_dispatch(zio_t *zio, zio_taskq_type_t q, boolean_t cutinline) 2177 { 2178 spa_t *spa = zio->io_spa; 2179 zio_type_t t = zio->io_type; 2180 2181 /* 2182 * If we're a config writer or a probe, the normal issue and 2183 * interrupt threads may all be blocked waiting for the config lock. 2184 * In this case, select the otherwise-unused taskq for ZIO_TYPE_NULL. 2185 */ 2186 if (zio->io_flags & (ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_PROBE)) 2187 t = ZIO_TYPE_NULL; 2188 2189 /* 2190 * A similar issue exists for the L2ARC write thread until L2ARC 2.0. 2191 */ 2192 if (t == ZIO_TYPE_WRITE && zio->io_vd && zio->io_vd->vdev_aux) 2193 t = ZIO_TYPE_NULL; 2194 2195 /* 2196 * If this is a high priority I/O, then use the high priority taskq if 2197 * available or cut the line otherwise. 2198 */ 2199 if (zio->io_priority == ZIO_PRIORITY_SYNC_WRITE) { 2200 if (spa->spa_zio_taskq[t][q + 1].stqs_count != 0) 2201 q++; 2202 else 2203 cutinline = B_TRUE; 2204 } 2205 2206 ASSERT3U(q, <, ZIO_TASKQ_TYPES); 2207 2208 spa_taskq_dispatch(spa, t, q, zio_execute, zio, cutinline); 2209 } 2210 2211 static boolean_t 2212 zio_taskq_member(zio_t *zio, zio_taskq_type_t q) 2213 { 2214 spa_t *spa = zio->io_spa; 2215 2216 taskq_t *tq = taskq_of_curthread(); 2217 2218 for (zio_type_t t = 0; t < ZIO_TYPES; t++) { 2219 spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q]; 2220 uint_t i; 2221 for (i = 0; i < tqs->stqs_count; i++) { 2222 if (tqs->stqs_taskq[i] == tq) 2223 return (B_TRUE); 2224 } 2225 } 2226 2227 return (B_FALSE); 2228 } 2229 2230 static zio_t * 2231 zio_issue_async(zio_t *zio) 2232 { 2233 ASSERT((zio->io_type != ZIO_TYPE_WRITE) || ZIO_HAS_ALLOCATOR(zio)); 2234 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE); 2235 return (NULL); 2236 } 2237 2238 void 2239 zio_interrupt(void *zio) 2240 { 2241 zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT, B_FALSE); 2242 } 2243 2244 void 2245 zio_delay_interrupt(zio_t *zio) 2246 { 2247 /* 2248 * The timeout_generic() function isn't defined in userspace, so 2249 * rather than trying to implement the function, the zio delay 2250 * functionality has been disabled for userspace builds. 2251 */ 2252 2253 #ifdef _KERNEL 2254 /* 2255 * If io_target_timestamp is zero, then no delay has been registered 2256 * for this IO, thus jump to the end of this function and "skip" the 2257 * delay; issuing it directly to the zio layer. 2258 */ 2259 if (zio->io_target_timestamp != 0) { 2260 hrtime_t now = gethrtime(); 2261 2262 if (now >= zio->io_target_timestamp) { 2263 /* 2264 * This IO has already taken longer than the target 2265 * delay to complete, so we don't want to delay it 2266 * any longer; we "miss" the delay and issue it 2267 * directly to the zio layer. This is likely due to 2268 * the target latency being set to a value less than 2269 * the underlying hardware can satisfy (e.g. delay 2270 * set to 1ms, but the disks take 10ms to complete an 2271 * IO request). 2272 */ 2273 2274 DTRACE_PROBE2(zio__delay__miss, zio_t *, zio, 2275 hrtime_t, now); 2276 2277 zio_interrupt(zio); 2278 } else { 2279 taskqid_t tid; 2280 hrtime_t diff = zio->io_target_timestamp - now; 2281 int ticks = MAX(1, NSEC_TO_TICK(diff)); 2282 clock_t expire_at_tick = ddi_get_lbolt() + ticks; 2283 2284 DTRACE_PROBE3(zio__delay__hit, zio_t *, zio, 2285 hrtime_t, now, hrtime_t, diff); 2286 2287 tid = taskq_dispatch_delay(system_taskq, zio_interrupt, 2288 zio, TQ_NOSLEEP, expire_at_tick); 2289 if (tid == TASKQID_INVALID) { 2290 /* 2291 * Couldn't allocate a task. Just finish the 2292 * zio without a delay. 2293 */ 2294 zio_interrupt(zio); 2295 } 2296 } 2297 return; 2298 } 2299 #endif 2300 DTRACE_PROBE1(zio__delay__skip, zio_t *, zio); 2301 zio_interrupt(zio); 2302 } 2303 2304 static void 2305 zio_deadman_impl(zio_t *pio, int ziodepth) 2306 { 2307 zio_t *cio, *cio_next; 2308 zio_link_t *zl = NULL; 2309 vdev_t *vd = pio->io_vd; 2310 uint64_t failmode = spa_get_deadman_failmode(pio->io_spa); 2311 2312 if (zio_deadman_log_all || (vd != NULL && vd->vdev_ops->vdev_op_leaf)) { 2313 vdev_queue_t *vq = vd ? &vd->vdev_queue : NULL; 2314 zbookmark_phys_t *zb = &pio->io_bookmark; 2315 uint64_t delta = gethrtime() - pio->io_timestamp; 2316 2317 zfs_dbgmsg("slow zio[%d]: zio=%px timestamp=%llu " 2318 "delta=%llu queued=%llu io=%llu " 2319 "path=%s " 2320 "last=%llu type=%d " 2321 "priority=%d flags=0x%llx stage=0x%x " 2322 "pipeline=0x%x pipeline-trace=0x%x " 2323 "objset=%llu object=%llu " 2324 "level=%llu blkid=%llu " 2325 "offset=%llu size=%llu " 2326 "error=%d", 2327 ziodepth, pio, pio->io_timestamp, 2328 (u_longlong_t)delta, pio->io_delta, pio->io_delay, 2329 vd ? vd->vdev_path : "NULL", 2330 vq ? vq->vq_io_complete_ts : 0, pio->io_type, 2331 pio->io_priority, (u_longlong_t)pio->io_flags, 2332 pio->io_stage, pio->io_pipeline, pio->io_pipeline_trace, 2333 (u_longlong_t)zb->zb_objset, (u_longlong_t)zb->zb_object, 2334 (u_longlong_t)zb->zb_level, (u_longlong_t)zb->zb_blkid, 2335 (u_longlong_t)pio->io_offset, (u_longlong_t)pio->io_size, 2336 pio->io_error); 2337 (void) zfs_ereport_post(FM_EREPORT_ZFS_DEADMAN, 2338 pio->io_spa, vd, zb, pio, 0); 2339 } 2340 2341 if (vd != NULL && vd->vdev_ops->vdev_op_leaf && 2342 list_is_empty(&pio->io_child_list) && 2343 failmode == ZIO_FAILURE_MODE_CONTINUE && 2344 taskq_empty_ent(&pio->io_tqent) && 2345 pio->io_queue_state == ZIO_QS_ACTIVE) { 2346 pio->io_error = EINTR; 2347 zio_interrupt(pio); 2348 } 2349 2350 mutex_enter(&pio->io_lock); 2351 for (cio = zio_walk_children(pio, &zl); cio != NULL; cio = cio_next) { 2352 cio_next = zio_walk_children(pio, &zl); 2353 zio_deadman_impl(cio, ziodepth + 1); 2354 } 2355 mutex_exit(&pio->io_lock); 2356 } 2357 2358 /* 2359 * Log the critical information describing this zio and all of its children 2360 * using the zfs_dbgmsg() interface then post deadman event for the ZED. 2361 */ 2362 void 2363 zio_deadman(zio_t *pio, const char *tag) 2364 { 2365 spa_t *spa = pio->io_spa; 2366 char *name = spa_name(spa); 2367 2368 if (!zfs_deadman_enabled || spa_suspended(spa)) 2369 return; 2370 2371 zio_deadman_impl(pio, 0); 2372 2373 switch (spa_get_deadman_failmode(spa)) { 2374 case ZIO_FAILURE_MODE_WAIT: 2375 zfs_dbgmsg("%s waiting for hung I/O to pool '%s'", tag, name); 2376 break; 2377 2378 case ZIO_FAILURE_MODE_CONTINUE: 2379 zfs_dbgmsg("%s restarting hung I/O for pool '%s'", tag, name); 2380 break; 2381 2382 case ZIO_FAILURE_MODE_PANIC: 2383 fm_panic("%s determined I/O to pool '%s' is hung.", tag, name); 2384 break; 2385 } 2386 } 2387 2388 /* 2389 * Execute the I/O pipeline until one of the following occurs: 2390 * (1) the I/O completes; (2) the pipeline stalls waiting for 2391 * dependent child I/Os; (3) the I/O issues, so we're waiting 2392 * for an I/O completion interrupt; (4) the I/O is delegated by 2393 * vdev-level caching or aggregation; (5) the I/O is deferred 2394 * due to vdev-level queueing; (6) the I/O is handed off to 2395 * another thread. In all cases, the pipeline stops whenever 2396 * there's no CPU work; it never burns a thread in cv_wait_io(). 2397 * 2398 * There's no locking on io_stage because there's no legitimate way 2399 * for multiple threads to be attempting to process the same I/O. 2400 */ 2401 static zio_pipe_stage_t *zio_pipeline[]; 2402 2403 /* 2404 * zio_execute() is a wrapper around the static function 2405 * __zio_execute() so that we can force __zio_execute() to be 2406 * inlined. This reduces stack overhead which is important 2407 * because __zio_execute() is called recursively in several zio 2408 * code paths. zio_execute() itself cannot be inlined because 2409 * it is externally visible. 2410 */ 2411 void 2412 zio_execute(void *zio) 2413 { 2414 fstrans_cookie_t cookie; 2415 2416 cookie = spl_fstrans_mark(); 2417 __zio_execute(zio); 2418 spl_fstrans_unmark(cookie); 2419 } 2420 2421 /* 2422 * Used to determine if in the current context the stack is sized large 2423 * enough to allow zio_execute() to be called recursively. A minimum 2424 * stack size of 16K is required to avoid needing to re-dispatch the zio. 2425 */ 2426 static boolean_t 2427 zio_execute_stack_check(zio_t *zio) 2428 { 2429 #if !defined(HAVE_LARGE_STACKS) 2430 dsl_pool_t *dp = spa_get_dsl(zio->io_spa); 2431 2432 /* Executing in txg_sync_thread() context. */ 2433 if (dp && curthread == dp->dp_tx.tx_sync_thread) 2434 return (B_TRUE); 2435 2436 /* Pool initialization outside of zio_taskq context. */ 2437 if (dp && spa_is_initializing(dp->dp_spa) && 2438 !zio_taskq_member(zio, ZIO_TASKQ_ISSUE) && 2439 !zio_taskq_member(zio, ZIO_TASKQ_ISSUE_HIGH)) 2440 return (B_TRUE); 2441 #else 2442 (void) zio; 2443 #endif /* HAVE_LARGE_STACKS */ 2444 2445 return (B_FALSE); 2446 } 2447 2448 __attribute__((always_inline)) 2449 static inline void 2450 __zio_execute(zio_t *zio) 2451 { 2452 ASSERT3U(zio->io_queued_timestamp, >, 0); 2453 2454 while (zio->io_stage < ZIO_STAGE_DONE) { 2455 enum zio_stage pipeline = zio->io_pipeline; 2456 enum zio_stage stage = zio->io_stage; 2457 2458 zio->io_executor = curthread; 2459 2460 ASSERT(!MUTEX_HELD(&zio->io_lock)); 2461 ASSERT(ISP2(stage)); 2462 ASSERT(zio->io_stall == NULL); 2463 2464 do { 2465 stage <<= 1; 2466 } while ((stage & pipeline) == 0); 2467 2468 ASSERT(stage <= ZIO_STAGE_DONE); 2469 2470 /* 2471 * If we are in interrupt context and this pipeline stage 2472 * will grab a config lock that is held across I/O, 2473 * or may wait for an I/O that needs an interrupt thread 2474 * to complete, issue async to avoid deadlock. 2475 * 2476 * For VDEV_IO_START, we cut in line so that the io will 2477 * be sent to disk promptly. 2478 */ 2479 if ((stage & ZIO_BLOCKING_STAGES) && zio->io_vd == NULL && 2480 zio_taskq_member(zio, ZIO_TASKQ_INTERRUPT)) { 2481 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ? 2482 zio_requeue_io_start_cut_in_line : B_FALSE; 2483 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut); 2484 return; 2485 } 2486 2487 /* 2488 * If the current context doesn't have large enough stacks 2489 * the zio must be issued asynchronously to prevent overflow. 2490 */ 2491 if (zio_execute_stack_check(zio)) { 2492 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ? 2493 zio_requeue_io_start_cut_in_line : B_FALSE; 2494 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut); 2495 return; 2496 } 2497 2498 zio->io_stage = stage; 2499 zio->io_pipeline_trace |= zio->io_stage; 2500 2501 /* 2502 * The zio pipeline stage returns the next zio to execute 2503 * (typically the same as this one), or NULL if we should 2504 * stop. 2505 */ 2506 zio = zio_pipeline[highbit64(stage) - 1](zio); 2507 2508 if (zio == NULL) 2509 return; 2510 } 2511 } 2512 2513 2514 /* 2515 * ========================================================================== 2516 * Initiate I/O, either sync or async 2517 * ========================================================================== 2518 */ 2519 int 2520 zio_wait(zio_t *zio) 2521 { 2522 /* 2523 * Some routines, like zio_free_sync(), may return a NULL zio 2524 * to avoid the performance overhead of creating and then destroying 2525 * an unneeded zio. For the callers' simplicity, we accept a NULL 2526 * zio and ignore it. 2527 */ 2528 if (zio == NULL) 2529 return (0); 2530 2531 long timeout = MSEC_TO_TICK(zfs_deadman_ziotime_ms); 2532 int error; 2533 2534 ASSERT3S(zio->io_stage, ==, ZIO_STAGE_OPEN); 2535 ASSERT3P(zio->io_executor, ==, NULL); 2536 2537 zio->io_waiter = curthread; 2538 ASSERT0(zio->io_queued_timestamp); 2539 zio->io_queued_timestamp = gethrtime(); 2540 2541 if (zio->io_type == ZIO_TYPE_WRITE) { 2542 spa_select_allocator(zio); 2543 } 2544 __zio_execute(zio); 2545 2546 mutex_enter(&zio->io_lock); 2547 while (zio->io_executor != NULL) { 2548 error = cv_timedwait_io(&zio->io_cv, &zio->io_lock, 2549 ddi_get_lbolt() + timeout); 2550 2551 if (zfs_deadman_enabled && error == -1 && 2552 gethrtime() - zio->io_queued_timestamp > 2553 spa_deadman_ziotime(zio->io_spa)) { 2554 mutex_exit(&zio->io_lock); 2555 timeout = MSEC_TO_TICK(zfs_deadman_checktime_ms); 2556 zio_deadman(zio, FTAG); 2557 mutex_enter(&zio->io_lock); 2558 } 2559 } 2560 mutex_exit(&zio->io_lock); 2561 2562 error = zio->io_error; 2563 zio_destroy(zio); 2564 2565 return (error); 2566 } 2567 2568 void 2569 zio_nowait(zio_t *zio) 2570 { 2571 /* 2572 * See comment in zio_wait(). 2573 */ 2574 if (zio == NULL) 2575 return; 2576 2577 ASSERT3P(zio->io_executor, ==, NULL); 2578 2579 if (zio->io_child_type == ZIO_CHILD_LOGICAL && 2580 list_is_empty(&zio->io_parent_list)) { 2581 zio_t *pio; 2582 2583 /* 2584 * This is a logical async I/O with no parent to wait for it. 2585 * We add it to the spa_async_root_zio "Godfather" I/O which 2586 * will ensure they complete prior to unloading the pool. 2587 */ 2588 spa_t *spa = zio->io_spa; 2589 pio = spa->spa_async_zio_root[CPU_SEQID_UNSTABLE]; 2590 2591 zio_add_child(pio, zio); 2592 } 2593 2594 ASSERT0(zio->io_queued_timestamp); 2595 zio->io_queued_timestamp = gethrtime(); 2596 if (zio->io_type == ZIO_TYPE_WRITE) { 2597 spa_select_allocator(zio); 2598 } 2599 __zio_execute(zio); 2600 } 2601 2602 /* 2603 * ========================================================================== 2604 * Reexecute, cancel, or suspend/resume failed I/O 2605 * ========================================================================== 2606 */ 2607 2608 static void 2609 zio_reexecute(void *arg) 2610 { 2611 zio_t *pio = arg; 2612 zio_t *cio, *cio_next, *gio; 2613 2614 ASSERT(pio->io_child_type == ZIO_CHILD_LOGICAL); 2615 ASSERT(pio->io_orig_stage == ZIO_STAGE_OPEN); 2616 ASSERT(pio->io_gang_leader == NULL); 2617 ASSERT(pio->io_gang_tree == NULL); 2618 2619 mutex_enter(&pio->io_lock); 2620 pio->io_flags = pio->io_orig_flags; 2621 pio->io_stage = pio->io_orig_stage; 2622 pio->io_pipeline = pio->io_orig_pipeline; 2623 pio->io_reexecute = 0; 2624 pio->io_flags |= ZIO_FLAG_REEXECUTED; 2625 pio->io_pipeline_trace = 0; 2626 pio->io_error = 0; 2627 pio->io_state[ZIO_WAIT_READY] = (pio->io_stage >= ZIO_STAGE_READY) || 2628 (pio->io_pipeline & ZIO_STAGE_READY) == 0; 2629 pio->io_state[ZIO_WAIT_DONE] = (pio->io_stage >= ZIO_STAGE_DONE); 2630 2631 /* 2632 * It's possible for a failed ZIO to be a descendant of more than one 2633 * ZIO tree. When reexecuting it, we have to be sure to add its wait 2634 * states to all parent wait counts. 2635 * 2636 * Those parents, in turn, may have other children that are currently 2637 * active, usually because they've already been reexecuted after 2638 * resuming. Those children may be executing and may call 2639 * zio_notify_parent() at the same time as we're updating our parent's 2640 * counts. To avoid races while updating the counts, we take 2641 * gio->io_lock before each update. 2642 */ 2643 zio_link_t *zl = NULL; 2644 while ((gio = zio_walk_parents(pio, &zl)) != NULL) { 2645 mutex_enter(&gio->io_lock); 2646 for (int w = 0; w < ZIO_WAIT_TYPES; w++) { 2647 gio->io_children[pio->io_child_type][w] += 2648 !pio->io_state[w]; 2649 } 2650 mutex_exit(&gio->io_lock); 2651 } 2652 2653 for (int c = 0; c < ZIO_CHILD_TYPES; c++) 2654 pio->io_child_error[c] = 0; 2655 2656 if (IO_IS_ALLOCATING(pio)) 2657 BP_ZERO(pio->io_bp); 2658 2659 /* 2660 * As we reexecute pio's children, new children could be created. 2661 * New children go to the head of pio's io_child_list, however, 2662 * so we will (correctly) not reexecute them. The key is that 2663 * the remainder of pio's io_child_list, from 'cio_next' onward, 2664 * cannot be affected by any side effects of reexecuting 'cio'. 2665 */ 2666 zl = NULL; 2667 for (cio = zio_walk_children(pio, &zl); cio != NULL; cio = cio_next) { 2668 cio_next = zio_walk_children(pio, &zl); 2669 mutex_exit(&pio->io_lock); 2670 zio_reexecute(cio); 2671 mutex_enter(&pio->io_lock); 2672 } 2673 mutex_exit(&pio->io_lock); 2674 2675 /* 2676 * Now that all children have been reexecuted, execute the parent. 2677 * We don't reexecute "The Godfather" I/O here as it's the 2678 * responsibility of the caller to wait on it. 2679 */ 2680 if (!(pio->io_flags & ZIO_FLAG_GODFATHER)) { 2681 pio->io_queued_timestamp = gethrtime(); 2682 __zio_execute(pio); 2683 } 2684 } 2685 2686 void 2687 zio_suspend(spa_t *spa, zio_t *zio, zio_suspend_reason_t reason) 2688 { 2689 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC) 2690 fm_panic("Pool '%s' has encountered an uncorrectable I/O " 2691 "failure and the failure mode property for this pool " 2692 "is set to panic.", spa_name(spa)); 2693 2694 if (reason != ZIO_SUSPEND_MMP) { 2695 cmn_err(CE_WARN, "Pool '%s' has encountered an uncorrectable " 2696 "I/O failure and has been suspended.", spa_name(spa)); 2697 } 2698 2699 (void) zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, 2700 NULL, NULL, 0); 2701 2702 mutex_enter(&spa->spa_suspend_lock); 2703 2704 if (spa->spa_suspend_zio_root == NULL) 2705 spa->spa_suspend_zio_root = zio_root(spa, NULL, NULL, 2706 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | 2707 ZIO_FLAG_GODFATHER); 2708 2709 spa->spa_suspended = reason; 2710 2711 if (zio != NULL) { 2712 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER)); 2713 ASSERT(zio != spa->spa_suspend_zio_root); 2714 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2715 ASSERT(zio_unique_parent(zio) == NULL); 2716 ASSERT(zio->io_stage == ZIO_STAGE_DONE); 2717 zio_add_child(spa->spa_suspend_zio_root, zio); 2718 } 2719 2720 mutex_exit(&spa->spa_suspend_lock); 2721 2722 txg_wait_kick(spa->spa_dsl_pool); 2723 } 2724 2725 int 2726 zio_resume(spa_t *spa) 2727 { 2728 zio_t *pio; 2729 2730 /* 2731 * Reexecute all previously suspended i/o. 2732 */ 2733 mutex_enter(&spa->spa_suspend_lock); 2734 if (spa->spa_suspended != ZIO_SUSPEND_NONE) 2735 cmn_err(CE_WARN, "Pool '%s' was suspended and is being " 2736 "resumed. Failed I/O will be retried.", 2737 spa_name(spa)); 2738 spa->spa_suspended = ZIO_SUSPEND_NONE; 2739 cv_broadcast(&spa->spa_suspend_cv); 2740 pio = spa->spa_suspend_zio_root; 2741 spa->spa_suspend_zio_root = NULL; 2742 mutex_exit(&spa->spa_suspend_lock); 2743 2744 if (pio == NULL) 2745 return (0); 2746 2747 zio_reexecute(pio); 2748 return (zio_wait(pio)); 2749 } 2750 2751 void 2752 zio_resume_wait(spa_t *spa) 2753 { 2754 mutex_enter(&spa->spa_suspend_lock); 2755 while (spa_suspended(spa)) 2756 cv_wait(&spa->spa_suspend_cv, &spa->spa_suspend_lock); 2757 mutex_exit(&spa->spa_suspend_lock); 2758 } 2759 2760 /* 2761 * ========================================================================== 2762 * Gang blocks. 2763 * 2764 * A gang block is a collection of small blocks that looks to the DMU 2765 * like one large block. When zio_dva_allocate() cannot find a block 2766 * of the requested size, due to either severe fragmentation or the pool 2767 * being nearly full, it calls zio_write_gang_block() to construct the 2768 * block from smaller fragments. 2769 * 2770 * A gang block consists of a gang header (zio_gbh_phys_t) and up to 2771 * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like 2772 * an indirect block: it's an array of block pointers. It consumes 2773 * only one sector and hence is allocatable regardless of fragmentation. 2774 * The gang header's bps point to its gang members, which hold the data. 2775 * 2776 * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg> 2777 * as the verifier to ensure uniqueness of the SHA256 checksum. 2778 * Critically, the gang block bp's blk_cksum is the checksum of the data, 2779 * not the gang header. This ensures that data block signatures (needed for 2780 * deduplication) are independent of how the block is physically stored. 2781 * 2782 * Gang blocks can be nested: a gang member may itself be a gang block. 2783 * Thus every gang block is a tree in which root and all interior nodes are 2784 * gang headers, and the leaves are normal blocks that contain user data. 2785 * The root of the gang tree is called the gang leader. 2786 * 2787 * To perform any operation (read, rewrite, free, claim) on a gang block, 2788 * zio_gang_assemble() first assembles the gang tree (minus data leaves) 2789 * in the io_gang_tree field of the original logical i/o by recursively 2790 * reading the gang leader and all gang headers below it. This yields 2791 * an in-core tree containing the contents of every gang header and the 2792 * bps for every constituent of the gang block. 2793 * 2794 * With the gang tree now assembled, zio_gang_issue() just walks the gang tree 2795 * and invokes a callback on each bp. To free a gang block, zio_gang_issue() 2796 * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp. 2797 * zio_claim_gang() provides a similarly trivial wrapper for zio_claim(). 2798 * zio_read_gang() is a wrapper around zio_read() that omits reading gang 2799 * headers, since we already have those in io_gang_tree. zio_rewrite_gang() 2800 * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite() 2801 * of the gang header plus zio_checksum_compute() of the data to update the 2802 * gang header's blk_cksum as described above. 2803 * 2804 * The two-phase assemble/issue model solves the problem of partial failure -- 2805 * what if you'd freed part of a gang block but then couldn't read the 2806 * gang header for another part? Assembling the entire gang tree first 2807 * ensures that all the necessary gang header I/O has succeeded before 2808 * starting the actual work of free, claim, or write. Once the gang tree 2809 * is assembled, free and claim are in-memory operations that cannot fail. 2810 * 2811 * In the event that a gang write fails, zio_dva_unallocate() walks the 2812 * gang tree to immediately free (i.e. insert back into the space map) 2813 * everything we've allocated. This ensures that we don't get ENOSPC 2814 * errors during repeated suspend/resume cycles due to a flaky device. 2815 * 2816 * Gang rewrites only happen during sync-to-convergence. If we can't assemble 2817 * the gang tree, we won't modify the block, so we can safely defer the free 2818 * (knowing that the block is still intact). If we *can* assemble the gang 2819 * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free 2820 * each constituent bp and we can allocate a new block on the next sync pass. 2821 * 2822 * In all cases, the gang tree allows complete recovery from partial failure. 2823 * ========================================================================== 2824 */ 2825 2826 static void 2827 zio_gang_issue_func_done(zio_t *zio) 2828 { 2829 abd_free(zio->io_abd); 2830 } 2831 2832 static zio_t * 2833 zio_read_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2834 uint64_t offset) 2835 { 2836 if (gn != NULL) 2837 return (pio); 2838 2839 return (zio_read(pio, pio->io_spa, bp, abd_get_offset(data, offset), 2840 BP_GET_PSIZE(bp), zio_gang_issue_func_done, 2841 NULL, pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), 2842 &pio->io_bookmark)); 2843 } 2844 2845 static zio_t * 2846 zio_rewrite_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2847 uint64_t offset) 2848 { 2849 zio_t *zio; 2850 2851 if (gn != NULL) { 2852 abd_t *gbh_abd = 2853 abd_get_from_buf(gn->gn_gbh, SPA_GANGBLOCKSIZE); 2854 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp, 2855 gbh_abd, SPA_GANGBLOCKSIZE, zio_gang_issue_func_done, NULL, 2856 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), 2857 &pio->io_bookmark); 2858 /* 2859 * As we rewrite each gang header, the pipeline will compute 2860 * a new gang block header checksum for it; but no one will 2861 * compute a new data checksum, so we do that here. The one 2862 * exception is the gang leader: the pipeline already computed 2863 * its data checksum because that stage precedes gang assembly. 2864 * (Presently, nothing actually uses interior data checksums; 2865 * this is just good hygiene.) 2866 */ 2867 if (gn != pio->io_gang_leader->io_gang_tree) { 2868 abd_t *buf = abd_get_offset(data, offset); 2869 2870 zio_checksum_compute(zio, BP_GET_CHECKSUM(bp), 2871 buf, BP_GET_PSIZE(bp)); 2872 2873 abd_free(buf); 2874 } 2875 /* 2876 * If we are here to damage data for testing purposes, 2877 * leave the GBH alone so that we can detect the damage. 2878 */ 2879 if (pio->io_gang_leader->io_flags & ZIO_FLAG_INDUCE_DAMAGE) 2880 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES; 2881 } else { 2882 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp, 2883 abd_get_offset(data, offset), BP_GET_PSIZE(bp), 2884 zio_gang_issue_func_done, NULL, pio->io_priority, 2885 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 2886 } 2887 2888 return (zio); 2889 } 2890 2891 static zio_t * 2892 zio_free_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2893 uint64_t offset) 2894 { 2895 (void) gn, (void) data, (void) offset; 2896 2897 zio_t *zio = zio_free_sync(pio, pio->io_spa, pio->io_txg, bp, 2898 ZIO_GANG_CHILD_FLAGS(pio)); 2899 if (zio == NULL) { 2900 zio = zio_null(pio, pio->io_spa, 2901 NULL, NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio)); 2902 } 2903 return (zio); 2904 } 2905 2906 static zio_t * 2907 zio_claim_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2908 uint64_t offset) 2909 { 2910 (void) gn, (void) data, (void) offset; 2911 return (zio_claim(pio, pio->io_spa, pio->io_txg, bp, 2912 NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio))); 2913 } 2914 2915 static zio_gang_issue_func_t *zio_gang_issue_func[ZIO_TYPES] = { 2916 NULL, 2917 zio_read_gang, 2918 zio_rewrite_gang, 2919 zio_free_gang, 2920 zio_claim_gang, 2921 NULL 2922 }; 2923 2924 static void zio_gang_tree_assemble_done(zio_t *zio); 2925 2926 static zio_gang_node_t * 2927 zio_gang_node_alloc(zio_gang_node_t **gnpp) 2928 { 2929 zio_gang_node_t *gn; 2930 2931 ASSERT(*gnpp == NULL); 2932 2933 gn = kmem_zalloc(sizeof (*gn), KM_SLEEP); 2934 gn->gn_gbh = zio_buf_alloc(SPA_GANGBLOCKSIZE); 2935 *gnpp = gn; 2936 2937 return (gn); 2938 } 2939 2940 static void 2941 zio_gang_node_free(zio_gang_node_t **gnpp) 2942 { 2943 zio_gang_node_t *gn = *gnpp; 2944 2945 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) 2946 ASSERT(gn->gn_child[g] == NULL); 2947 2948 zio_buf_free(gn->gn_gbh, SPA_GANGBLOCKSIZE); 2949 kmem_free(gn, sizeof (*gn)); 2950 *gnpp = NULL; 2951 } 2952 2953 static void 2954 zio_gang_tree_free(zio_gang_node_t **gnpp) 2955 { 2956 zio_gang_node_t *gn = *gnpp; 2957 2958 if (gn == NULL) 2959 return; 2960 2961 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) 2962 zio_gang_tree_free(&gn->gn_child[g]); 2963 2964 zio_gang_node_free(gnpp); 2965 } 2966 2967 static void 2968 zio_gang_tree_assemble(zio_t *gio, blkptr_t *bp, zio_gang_node_t **gnpp) 2969 { 2970 zio_gang_node_t *gn = zio_gang_node_alloc(gnpp); 2971 abd_t *gbh_abd = abd_get_from_buf(gn->gn_gbh, SPA_GANGBLOCKSIZE); 2972 2973 ASSERT(gio->io_gang_leader == gio); 2974 ASSERT(BP_IS_GANG(bp)); 2975 2976 zio_nowait(zio_read(gio, gio->io_spa, bp, gbh_abd, SPA_GANGBLOCKSIZE, 2977 zio_gang_tree_assemble_done, gn, gio->io_priority, 2978 ZIO_GANG_CHILD_FLAGS(gio), &gio->io_bookmark)); 2979 } 2980 2981 static void 2982 zio_gang_tree_assemble_done(zio_t *zio) 2983 { 2984 zio_t *gio = zio->io_gang_leader; 2985 zio_gang_node_t *gn = zio->io_private; 2986 blkptr_t *bp = zio->io_bp; 2987 2988 ASSERT(gio == zio_unique_parent(zio)); 2989 ASSERT(list_is_empty(&zio->io_child_list)); 2990 2991 if (zio->io_error) 2992 return; 2993 2994 /* this ABD was created from a linear buf in zio_gang_tree_assemble */ 2995 if (BP_SHOULD_BYTESWAP(bp)) 2996 byteswap_uint64_array(abd_to_buf(zio->io_abd), zio->io_size); 2997 2998 ASSERT3P(abd_to_buf(zio->io_abd), ==, gn->gn_gbh); 2999 ASSERT(zio->io_size == SPA_GANGBLOCKSIZE); 3000 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC); 3001 3002 abd_free(zio->io_abd); 3003 3004 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 3005 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g]; 3006 if (!BP_IS_GANG(gbp)) 3007 continue; 3008 zio_gang_tree_assemble(gio, gbp, &gn->gn_child[g]); 3009 } 3010 } 3011 3012 static void 3013 zio_gang_tree_issue(zio_t *pio, zio_gang_node_t *gn, blkptr_t *bp, abd_t *data, 3014 uint64_t offset) 3015 { 3016 zio_t *gio = pio->io_gang_leader; 3017 zio_t *zio; 3018 3019 ASSERT(BP_IS_GANG(bp) == !!gn); 3020 ASSERT(BP_GET_CHECKSUM(bp) == BP_GET_CHECKSUM(gio->io_bp)); 3021 ASSERT(BP_GET_LSIZE(bp) == BP_GET_PSIZE(bp) || gn == gio->io_gang_tree); 3022 3023 /* 3024 * If you're a gang header, your data is in gn->gn_gbh. 3025 * If you're a gang member, your data is in 'data' and gn == NULL. 3026 */ 3027 zio = zio_gang_issue_func[gio->io_type](pio, bp, gn, data, offset); 3028 3029 if (gn != NULL) { 3030 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC); 3031 3032 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 3033 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g]; 3034 if (BP_IS_HOLE(gbp)) 3035 continue; 3036 zio_gang_tree_issue(zio, gn->gn_child[g], gbp, data, 3037 offset); 3038 offset += BP_GET_PSIZE(gbp); 3039 } 3040 } 3041 3042 if (gn == gio->io_gang_tree) 3043 ASSERT3U(gio->io_size, ==, offset); 3044 3045 if (zio != pio) 3046 zio_nowait(zio); 3047 } 3048 3049 static zio_t * 3050 zio_gang_assemble(zio_t *zio) 3051 { 3052 blkptr_t *bp = zio->io_bp; 3053 3054 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == NULL); 3055 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 3056 3057 zio->io_gang_leader = zio; 3058 3059 zio_gang_tree_assemble(zio, bp, &zio->io_gang_tree); 3060 3061 return (zio); 3062 } 3063 3064 static zio_t * 3065 zio_gang_issue(zio_t *zio) 3066 { 3067 blkptr_t *bp = zio->io_bp; 3068 3069 if (zio_wait_for_children(zio, ZIO_CHILD_GANG_BIT, ZIO_WAIT_DONE)) { 3070 return (NULL); 3071 } 3072 3073 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == zio); 3074 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 3075 3076 if (zio->io_child_error[ZIO_CHILD_GANG] == 0) 3077 zio_gang_tree_issue(zio, zio->io_gang_tree, bp, zio->io_abd, 3078 0); 3079 else 3080 zio_gang_tree_free(&zio->io_gang_tree); 3081 3082 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 3083 3084 return (zio); 3085 } 3086 3087 static void 3088 zio_gang_inherit_allocator(zio_t *pio, zio_t *cio) 3089 { 3090 cio->io_allocator = pio->io_allocator; 3091 } 3092 3093 static void 3094 zio_write_gang_member_ready(zio_t *zio) 3095 { 3096 zio_t *pio = zio_unique_parent(zio); 3097 dva_t *cdva = zio->io_bp->blk_dva; 3098 dva_t *pdva = pio->io_bp->blk_dva; 3099 uint64_t asize; 3100 zio_t *gio __maybe_unused = zio->io_gang_leader; 3101 3102 if (BP_IS_HOLE(zio->io_bp)) 3103 return; 3104 3105 /* 3106 * If we're getting direct-invoked from zio_write_gang_block(), 3107 * the bp_orig will be set. 3108 */ 3109 ASSERT(BP_IS_HOLE(&zio->io_bp_orig) || 3110 zio->io_flags & ZIO_FLAG_PREALLOCATED); 3111 3112 ASSERT(zio->io_child_type == ZIO_CHILD_GANG); 3113 ASSERT3U(zio->io_prop.zp_copies, ==, gio->io_prop.zp_copies); 3114 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(zio->io_bp)); 3115 ASSERT3U(pio->io_prop.zp_copies, <=, BP_GET_NDVAS(pio->io_bp)); 3116 VERIFY3U(BP_GET_NDVAS(zio->io_bp), <=, BP_GET_NDVAS(pio->io_bp)); 3117 3118 mutex_enter(&pio->io_lock); 3119 for (int d = 0; d < BP_GET_NDVAS(zio->io_bp); d++) { 3120 ASSERT(DVA_GET_GANG(&pdva[d])); 3121 asize = DVA_GET_ASIZE(&pdva[d]); 3122 asize += DVA_GET_ASIZE(&cdva[d]); 3123 DVA_SET_ASIZE(&pdva[d], asize); 3124 } 3125 mutex_exit(&pio->io_lock); 3126 } 3127 3128 static void 3129 zio_write_gang_done(zio_t *zio) 3130 { 3131 /* 3132 * The io_abd field will be NULL for a zio with no data. The io_flags 3133 * will initially have the ZIO_FLAG_NODATA bit flag set, but we can't 3134 * check for it here as it is cleared in zio_ready. 3135 */ 3136 if (zio->io_abd != NULL) 3137 abd_free(zio->io_abd); 3138 } 3139 3140 static zio_t * 3141 zio_write_gang_block(zio_t *pio, metaslab_class_t *mc) 3142 { 3143 spa_t *spa = pio->io_spa; 3144 blkptr_t *bp = pio->io_bp; 3145 zio_t *gio = pio->io_gang_leader; 3146 zio_t *zio; 3147 zio_gang_node_t *gn, **gnpp; 3148 zio_gbh_phys_t *gbh; 3149 abd_t *gbh_abd; 3150 uint64_t txg = pio->io_txg; 3151 uint64_t resid = pio->io_size; 3152 zio_prop_t zp; 3153 int error; 3154 boolean_t has_data = !(pio->io_flags & ZIO_FLAG_NODATA); 3155 3156 /* 3157 * Store multiple copies of the GBH, so that we can still traverse 3158 * all the data (e.g. to free or scrub) even if a block is damaged. 3159 * This value respects the redundant_metadata property. 3160 */ 3161 int gbh_copies = gio->io_prop.zp_gang_copies; 3162 if (gbh_copies == 0) { 3163 /* 3164 * This should only happen in the case where we're filling in 3165 * DDT entries for a parent that wants more copies than the DDT 3166 * has. In that case, we cannot gang without creating a mixed 3167 * blkptr, which is illegal. 3168 */ 3169 ASSERT3U(gio->io_child_type, ==, ZIO_CHILD_DDT); 3170 pio->io_error = EAGAIN; 3171 return (pio); 3172 } 3173 ASSERT3S(gbh_copies, >, 0); 3174 ASSERT3S(gbh_copies, <=, SPA_DVAS_PER_BP); 3175 3176 ASSERT(ZIO_HAS_ALLOCATOR(pio)); 3177 int flags = METASLAB_GANG_HEADER; 3178 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 3179 ASSERT(pio->io_priority == ZIO_PRIORITY_ASYNC_WRITE); 3180 ASSERT(has_data); 3181 3182 flags |= METASLAB_ASYNC_ALLOC; 3183 } 3184 3185 error = metaslab_alloc(spa, mc, SPA_GANGBLOCKSIZE, 3186 bp, gbh_copies, txg, pio == gio ? NULL : gio->io_bp, flags, 3187 &pio->io_alloc_list, pio->io_allocator, pio); 3188 if (error) { 3189 pio->io_error = error; 3190 return (pio); 3191 } 3192 3193 if (pio == gio) { 3194 gnpp = &gio->io_gang_tree; 3195 } else { 3196 gnpp = pio->io_private; 3197 ASSERT(pio->io_ready == zio_write_gang_member_ready); 3198 } 3199 3200 gn = zio_gang_node_alloc(gnpp); 3201 gbh = gn->gn_gbh; 3202 memset(gbh, 0, SPA_GANGBLOCKSIZE); 3203 gbh_abd = abd_get_from_buf(gbh, SPA_GANGBLOCKSIZE); 3204 3205 /* 3206 * Create the gang header. 3207 */ 3208 zio = zio_rewrite(pio, spa, txg, bp, gbh_abd, SPA_GANGBLOCKSIZE, 3209 zio_write_gang_done, NULL, pio->io_priority, 3210 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 3211 3212 zio_gang_inherit_allocator(pio, zio); 3213 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 3214 boolean_t more; 3215 VERIFY(metaslab_class_throttle_reserve(mc, gbh_copies, 3216 zio, B_TRUE, &more)); 3217 } 3218 3219 /* 3220 * Create and nowait the gang children. First, we try to do 3221 * opportunistic allocations. If that fails to generate enough 3222 * space, we fall back to normal zio_write calls for nested gang. 3223 */ 3224 for (int g = 0; resid != 0; g++) { 3225 flags &= METASLAB_ASYNC_ALLOC; 3226 flags |= METASLAB_GANG_CHILD; 3227 zp.zp_checksum = gio->io_prop.zp_checksum; 3228 zp.zp_compress = ZIO_COMPRESS_OFF; 3229 zp.zp_complevel = gio->io_prop.zp_complevel; 3230 zp.zp_type = zp.zp_storage_type = DMU_OT_NONE; 3231 zp.zp_level = 0; 3232 zp.zp_copies = gio->io_prop.zp_copies; 3233 zp.zp_gang_copies = gio->io_prop.zp_gang_copies; 3234 zp.zp_dedup = B_FALSE; 3235 zp.zp_dedup_verify = B_FALSE; 3236 zp.zp_nopwrite = B_FALSE; 3237 zp.zp_encrypt = gio->io_prop.zp_encrypt; 3238 zp.zp_byteorder = gio->io_prop.zp_byteorder; 3239 zp.zp_direct_write = B_FALSE; 3240 memset(zp.zp_salt, 0, ZIO_DATA_SALT_LEN); 3241 memset(zp.zp_iv, 0, ZIO_DATA_IV_LEN); 3242 memset(zp.zp_mac, 0, ZIO_DATA_MAC_LEN); 3243 3244 uint64_t min_size = zio_roundup_alloc_size(spa, 3245 resid / (SPA_GBH_NBLKPTRS - g)); 3246 min_size = MIN(min_size, resid); 3247 bp = &gbh->zg_blkptr[g]; 3248 3249 zio_alloc_list_t cio_list; 3250 metaslab_trace_init(&cio_list); 3251 uint64_t allocated_size = UINT64_MAX; 3252 error = metaslab_alloc_range(spa, mc, min_size, resid, 3253 bp, gio->io_prop.zp_copies, txg, NULL, 3254 flags, &cio_list, zio->io_allocator, NULL, &allocated_size); 3255 3256 boolean_t allocated = error == 0; 3257 3258 uint64_t psize = allocated ? MIN(resid, allocated_size) : 3259 min_size; 3260 3261 zio_t *cio = zio_write(zio, spa, txg, bp, has_data ? 3262 abd_get_offset(pio->io_abd, pio->io_size - resid) : NULL, 3263 psize, psize, &zp, zio_write_gang_member_ready, NULL, 3264 zio_write_gang_done, &gn->gn_child[g], pio->io_priority, 3265 ZIO_GANG_CHILD_FLAGS(pio) | 3266 (allocated ? ZIO_FLAG_PREALLOCATED : 0), &pio->io_bookmark); 3267 3268 resid -= psize; 3269 zio_gang_inherit_allocator(zio, cio); 3270 if (allocated) { 3271 metaslab_trace_move(&cio_list, &cio->io_alloc_list); 3272 metaslab_group_alloc_increment_all(spa, 3273 &cio->io_bp_orig, zio->io_allocator, flags, psize, 3274 cio); 3275 } 3276 /* 3277 * We do not reserve for the child writes, since we already 3278 * reserved for the parent. Unreserve though will be called 3279 * for individual children. We can do this since sum of all 3280 * child's physical sizes is equal to parent's physical size. 3281 * It would not work for potentially bigger allocation sizes. 3282 */ 3283 3284 zio_nowait(cio); 3285 } 3286 3287 /* 3288 * Set pio's pipeline to just wait for zio to finish. 3289 */ 3290 pio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 3291 3292 zio_nowait(zio); 3293 3294 return (pio); 3295 } 3296 3297 /* 3298 * The zio_nop_write stage in the pipeline determines if allocating a 3299 * new bp is necessary. The nopwrite feature can handle writes in 3300 * either syncing or open context (i.e. zil writes) and as a result is 3301 * mutually exclusive with dedup. 3302 * 3303 * By leveraging a cryptographically secure checksum, such as SHA256, we 3304 * can compare the checksums of the new data and the old to determine if 3305 * allocating a new block is required. Note that our requirements for 3306 * cryptographic strength are fairly weak: there can't be any accidental 3307 * hash collisions, but we don't need to be secure against intentional 3308 * (malicious) collisions. To trigger a nopwrite, you have to be able 3309 * to write the file to begin with, and triggering an incorrect (hash 3310 * collision) nopwrite is no worse than simply writing to the file. 3311 * That said, there are no known attacks against the checksum algorithms 3312 * used for nopwrite, assuming that the salt and the checksums 3313 * themselves remain secret. 3314 */ 3315 static zio_t * 3316 zio_nop_write(zio_t *zio) 3317 { 3318 blkptr_t *bp = zio->io_bp; 3319 blkptr_t *bp_orig = &zio->io_bp_orig; 3320 zio_prop_t *zp = &zio->io_prop; 3321 3322 ASSERT(BP_IS_HOLE(bp)); 3323 ASSERT(BP_GET_LEVEL(bp) == 0); 3324 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 3325 ASSERT(zp->zp_nopwrite); 3326 ASSERT(!zp->zp_dedup); 3327 ASSERT(zio->io_bp_override == NULL); 3328 ASSERT(IO_IS_ALLOCATING(zio)); 3329 3330 /* 3331 * Check to see if the original bp and the new bp have matching 3332 * characteristics (i.e. same checksum, compression algorithms, etc). 3333 * If they don't then just continue with the pipeline which will 3334 * allocate a new bp. 3335 */ 3336 if (BP_IS_HOLE(bp_orig) || 3337 !(zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_flags & 3338 ZCHECKSUM_FLAG_NOPWRITE) || 3339 BP_IS_ENCRYPTED(bp) || BP_IS_ENCRYPTED(bp_orig) || 3340 BP_GET_CHECKSUM(bp) != BP_GET_CHECKSUM(bp_orig) || 3341 BP_GET_COMPRESS(bp) != BP_GET_COMPRESS(bp_orig) || 3342 BP_GET_DEDUP(bp) != BP_GET_DEDUP(bp_orig) || 3343 zp->zp_copies != BP_GET_NDVAS(bp_orig)) 3344 return (zio); 3345 3346 /* 3347 * If the checksums match then reset the pipeline so that we 3348 * avoid allocating a new bp and issuing any I/O. 3349 */ 3350 if (ZIO_CHECKSUM_EQUAL(bp->blk_cksum, bp_orig->blk_cksum)) { 3351 ASSERT(zio_checksum_table[zp->zp_checksum].ci_flags & 3352 ZCHECKSUM_FLAG_NOPWRITE); 3353 ASSERT3U(BP_GET_PSIZE(bp), ==, BP_GET_PSIZE(bp_orig)); 3354 ASSERT3U(BP_GET_LSIZE(bp), ==, BP_GET_LSIZE(bp_orig)); 3355 ASSERT(zp->zp_compress != ZIO_COMPRESS_OFF); 3356 ASSERT3U(bp->blk_prop, ==, bp_orig->blk_prop); 3357 3358 /* 3359 * If we're overwriting a block that is currently on an 3360 * indirect vdev, then ignore the nopwrite request and 3361 * allow a new block to be allocated on a concrete vdev. 3362 */ 3363 spa_config_enter(zio->io_spa, SCL_VDEV, FTAG, RW_READER); 3364 for (int d = 0; d < BP_GET_NDVAS(bp_orig); d++) { 3365 vdev_t *tvd = vdev_lookup_top(zio->io_spa, 3366 DVA_GET_VDEV(&bp_orig->blk_dva[d])); 3367 if (tvd->vdev_ops == &vdev_indirect_ops) { 3368 spa_config_exit(zio->io_spa, SCL_VDEV, FTAG); 3369 return (zio); 3370 } 3371 } 3372 spa_config_exit(zio->io_spa, SCL_VDEV, FTAG); 3373 3374 *bp = *bp_orig; 3375 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 3376 zio->io_flags |= ZIO_FLAG_NOPWRITE; 3377 } 3378 3379 return (zio); 3380 } 3381 3382 /* 3383 * ========================================================================== 3384 * Block Reference Table 3385 * ========================================================================== 3386 */ 3387 static zio_t * 3388 zio_brt_free(zio_t *zio) 3389 { 3390 blkptr_t *bp; 3391 3392 bp = zio->io_bp; 3393 3394 if (BP_GET_LEVEL(bp) > 0 || 3395 BP_IS_METADATA(bp) || 3396 !brt_maybe_exists(zio->io_spa, bp)) { 3397 return (zio); 3398 } 3399 3400 if (!brt_entry_decref(zio->io_spa, bp)) { 3401 /* 3402 * This isn't the last reference, so we cannot free 3403 * the data yet. 3404 */ 3405 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 3406 } 3407 3408 return (zio); 3409 } 3410 3411 /* 3412 * ========================================================================== 3413 * Dedup 3414 * ========================================================================== 3415 */ 3416 static void 3417 zio_ddt_child_read_done(zio_t *zio) 3418 { 3419 blkptr_t *bp = zio->io_bp; 3420 ddt_t *ddt; 3421 ddt_entry_t *dde = zio->io_private; 3422 zio_t *pio = zio_unique_parent(zio); 3423 3424 mutex_enter(&pio->io_lock); 3425 ddt = ddt_select(zio->io_spa, bp); 3426 3427 if (zio->io_error == 0) { 3428 ddt_phys_variant_t v = ddt_phys_select(ddt, dde, bp); 3429 /* this phys variant doesn't need repair */ 3430 ddt_phys_clear(dde->dde_phys, v); 3431 } 3432 3433 if (zio->io_error == 0 && dde->dde_io->dde_repair_abd == NULL) 3434 dde->dde_io->dde_repair_abd = zio->io_abd; 3435 else 3436 abd_free(zio->io_abd); 3437 mutex_exit(&pio->io_lock); 3438 } 3439 3440 static zio_t * 3441 zio_ddt_read_start(zio_t *zio) 3442 { 3443 blkptr_t *bp = zio->io_bp; 3444 3445 ASSERT(BP_GET_DEDUP(bp)); 3446 ASSERT(BP_GET_PSIZE(bp) == zio->io_size); 3447 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 3448 3449 if (zio->io_child_error[ZIO_CHILD_DDT]) { 3450 ddt_t *ddt = ddt_select(zio->io_spa, bp); 3451 ddt_entry_t *dde = ddt_repair_start(ddt, bp); 3452 ddt_phys_variant_t v_self = ddt_phys_select(ddt, dde, bp); 3453 ddt_univ_phys_t *ddp = dde->dde_phys; 3454 blkptr_t blk; 3455 3456 ASSERT(zio->io_vsd == NULL); 3457 zio->io_vsd = dde; 3458 3459 if (v_self == DDT_PHYS_NONE) 3460 return (zio); 3461 3462 /* issue I/O for the other copies */ 3463 for (int p = 0; p < DDT_NPHYS(ddt); p++) { 3464 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3465 3466 if (ddt_phys_birth(ddp, v) == 0 || v == v_self) 3467 continue; 3468 3469 ddt_bp_create(ddt->ddt_checksum, &dde->dde_key, 3470 ddp, v, &blk); 3471 zio_nowait(zio_read(zio, zio->io_spa, &blk, 3472 abd_alloc_for_io(zio->io_size, B_TRUE), 3473 zio->io_size, zio_ddt_child_read_done, dde, 3474 zio->io_priority, ZIO_DDT_CHILD_FLAGS(zio) | 3475 ZIO_FLAG_DONT_PROPAGATE, &zio->io_bookmark)); 3476 } 3477 return (zio); 3478 } 3479 3480 zio_nowait(zio_read(zio, zio->io_spa, bp, 3481 zio->io_abd, zio->io_size, NULL, NULL, zio->io_priority, 3482 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark)); 3483 3484 return (zio); 3485 } 3486 3487 static zio_t * 3488 zio_ddt_read_done(zio_t *zio) 3489 { 3490 blkptr_t *bp = zio->io_bp; 3491 3492 if (zio_wait_for_children(zio, ZIO_CHILD_DDT_BIT, ZIO_WAIT_DONE)) { 3493 return (NULL); 3494 } 3495 3496 ASSERT(BP_GET_DEDUP(bp)); 3497 ASSERT(BP_GET_PSIZE(bp) == zio->io_size); 3498 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 3499 3500 if (zio->io_child_error[ZIO_CHILD_DDT]) { 3501 ddt_t *ddt = ddt_select(zio->io_spa, bp); 3502 ddt_entry_t *dde = zio->io_vsd; 3503 if (ddt == NULL) { 3504 ASSERT(spa_load_state(zio->io_spa) != SPA_LOAD_NONE); 3505 return (zio); 3506 } 3507 if (dde == NULL) { 3508 zio->io_stage = ZIO_STAGE_DDT_READ_START >> 1; 3509 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE); 3510 return (NULL); 3511 } 3512 if (dde->dde_io->dde_repair_abd != NULL) { 3513 abd_copy(zio->io_abd, dde->dde_io->dde_repair_abd, 3514 zio->io_size); 3515 zio->io_child_error[ZIO_CHILD_DDT] = 0; 3516 } 3517 ddt_repair_done(ddt, dde); 3518 zio->io_vsd = NULL; 3519 } 3520 3521 ASSERT(zio->io_vsd == NULL); 3522 3523 return (zio); 3524 } 3525 3526 static boolean_t 3527 zio_ddt_collision(zio_t *zio, ddt_t *ddt, ddt_entry_t *dde) 3528 { 3529 spa_t *spa = zio->io_spa; 3530 boolean_t do_raw = !!(zio->io_flags & ZIO_FLAG_RAW); 3531 3532 ASSERT(!(zio->io_bp_override && do_raw)); 3533 3534 /* 3535 * Note: we compare the original data, not the transformed data, 3536 * because when zio->io_bp is an override bp, we will not have 3537 * pushed the I/O transforms. That's an important optimization 3538 * because otherwise we'd compress/encrypt all dmu_sync() data twice. 3539 * However, we should never get a raw, override zio so in these 3540 * cases we can compare the io_abd directly. This is useful because 3541 * it allows us to do dedup verification even if we don't have access 3542 * to the original data (for instance, if the encryption keys aren't 3543 * loaded). 3544 */ 3545 3546 for (int p = 0; p < DDT_NPHYS(ddt); p++) { 3547 if (DDT_PHYS_IS_DITTO(ddt, p)) 3548 continue; 3549 3550 if (dde->dde_io == NULL) 3551 continue; 3552 3553 zio_t *lio = dde->dde_io->dde_lead_zio[p]; 3554 if (lio == NULL) 3555 continue; 3556 3557 if (do_raw) 3558 return (lio->io_size != zio->io_size || 3559 abd_cmp(zio->io_abd, lio->io_abd) != 0); 3560 3561 return (lio->io_orig_size != zio->io_orig_size || 3562 abd_cmp(zio->io_orig_abd, lio->io_orig_abd) != 0); 3563 } 3564 3565 for (int p = 0; p < DDT_NPHYS(ddt); p++) { 3566 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3567 uint64_t phys_birth = ddt_phys_birth(dde->dde_phys, v); 3568 3569 if (phys_birth != 0 && do_raw) { 3570 blkptr_t blk = *zio->io_bp; 3571 uint64_t psize; 3572 abd_t *tmpabd; 3573 int error; 3574 3575 ddt_bp_fill(dde->dde_phys, v, &blk, phys_birth); 3576 psize = BP_GET_PSIZE(&blk); 3577 3578 if (psize != zio->io_size) 3579 return (B_TRUE); 3580 3581 ddt_exit(ddt); 3582 3583 tmpabd = abd_alloc_for_io(psize, B_TRUE); 3584 3585 error = zio_wait(zio_read(NULL, spa, &blk, tmpabd, 3586 psize, NULL, NULL, ZIO_PRIORITY_SYNC_READ, 3587 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | 3588 ZIO_FLAG_RAW, &zio->io_bookmark)); 3589 3590 if (error == 0) { 3591 if (abd_cmp(tmpabd, zio->io_abd) != 0) 3592 error = SET_ERROR(ENOENT); 3593 } 3594 3595 abd_free(tmpabd); 3596 ddt_enter(ddt); 3597 return (error != 0); 3598 } else if (phys_birth != 0) { 3599 arc_buf_t *abuf = NULL; 3600 arc_flags_t aflags = ARC_FLAG_WAIT; 3601 blkptr_t blk = *zio->io_bp; 3602 int error; 3603 3604 ddt_bp_fill(dde->dde_phys, v, &blk, phys_birth); 3605 3606 if (BP_GET_LSIZE(&blk) != zio->io_orig_size) 3607 return (B_TRUE); 3608 3609 ddt_exit(ddt); 3610 3611 error = arc_read(NULL, spa, &blk, 3612 arc_getbuf_func, &abuf, ZIO_PRIORITY_SYNC_READ, 3613 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, 3614 &aflags, &zio->io_bookmark); 3615 3616 if (error == 0) { 3617 if (abd_cmp_buf(zio->io_orig_abd, abuf->b_data, 3618 zio->io_orig_size) != 0) 3619 error = SET_ERROR(ENOENT); 3620 arc_buf_destroy(abuf, &abuf); 3621 } 3622 3623 ddt_enter(ddt); 3624 return (error != 0); 3625 } 3626 } 3627 3628 return (B_FALSE); 3629 } 3630 3631 static void 3632 zio_ddt_child_write_done(zio_t *zio) 3633 { 3634 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp); 3635 ddt_entry_t *dde = zio->io_private; 3636 3637 zio_link_t *zl = NULL; 3638 ASSERT3P(zio_walk_parents(zio, &zl), !=, NULL); 3639 3640 int p = DDT_PHYS_FOR_COPIES(ddt, zio->io_prop.zp_copies); 3641 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3642 ddt_univ_phys_t *ddp = dde->dde_phys; 3643 3644 ddt_enter(ddt); 3645 3646 /* we're the lead, so once we're done there's no one else outstanding */ 3647 if (dde->dde_io->dde_lead_zio[p] == zio) 3648 dde->dde_io->dde_lead_zio[p] = NULL; 3649 3650 ddt_univ_phys_t *orig = &dde->dde_io->dde_orig_phys; 3651 3652 if (zio->io_error != 0) { 3653 /* 3654 * The write failed, so we're about to abort the entire IO 3655 * chain. We need to revert the entry back to what it was at 3656 * the last time it was successfully extended. 3657 */ 3658 ddt_phys_unextend(ddp, orig, v); 3659 ddt_phys_clear(orig, v); 3660 3661 ddt_exit(ddt); 3662 return; 3663 } 3664 3665 /* 3666 * Add references for all dedup writes that were waiting on the 3667 * physical one, skipping any other physical writes that are waiting. 3668 */ 3669 zio_t *pio; 3670 zl = NULL; 3671 while ((pio = zio_walk_parents(zio, &zl)) != NULL) { 3672 if (!(pio->io_flags & ZIO_FLAG_DDT_CHILD)) 3673 ddt_phys_addref(ddp, v); 3674 } 3675 3676 /* 3677 * We've successfully added new DVAs to the entry. Clear the saved 3678 * state or, if there's still outstanding IO, remember it so we can 3679 * revert to a known good state if that IO fails. 3680 */ 3681 if (dde->dde_io->dde_lead_zio[p] == NULL) 3682 ddt_phys_clear(orig, v); 3683 else 3684 ddt_phys_copy(orig, ddp, v); 3685 3686 ddt_exit(ddt); 3687 } 3688 3689 static void 3690 zio_ddt_child_write_ready(zio_t *zio) 3691 { 3692 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp); 3693 ddt_entry_t *dde = zio->io_private; 3694 3695 zio_link_t *zl = NULL; 3696 ASSERT3P(zio_walk_parents(zio, &zl), !=, NULL); 3697 3698 int p = DDT_PHYS_FOR_COPIES(ddt, zio->io_prop.zp_copies); 3699 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3700 3701 if (ddt_phys_is_gang(dde->dde_phys, v)) { 3702 for (int i = 0; i < BP_GET_NDVAS(zio->io_bp); i++) { 3703 dva_t *d = &zio->io_bp->blk_dva[i]; 3704 metaslab_group_alloc_decrement(zio->io_spa, 3705 DVA_GET_VDEV(d), zio->io_allocator, 3706 METASLAB_ASYNC_ALLOC, zio->io_size, zio); 3707 } 3708 zio->io_error = EAGAIN; 3709 } 3710 3711 if (zio->io_error != 0) 3712 return; 3713 3714 ddt_enter(ddt); 3715 3716 ddt_phys_extend(dde->dde_phys, v, zio->io_bp); 3717 3718 zio_t *pio; 3719 zl = NULL; 3720 while ((pio = zio_walk_parents(zio, &zl)) != NULL) { 3721 if (!(pio->io_flags & ZIO_FLAG_DDT_CHILD)) 3722 ddt_bp_fill(dde->dde_phys, v, pio->io_bp, zio->io_txg); 3723 } 3724 3725 ddt_exit(ddt); 3726 } 3727 3728 static zio_t * 3729 zio_ddt_write(zio_t *zio) 3730 { 3731 spa_t *spa = zio->io_spa; 3732 blkptr_t *bp = zio->io_bp; 3733 uint64_t txg = zio->io_txg; 3734 zio_prop_t *zp = &zio->io_prop; 3735 ddt_t *ddt = ddt_select(spa, bp); 3736 ddt_entry_t *dde; 3737 3738 ASSERT(BP_GET_DEDUP(bp)); 3739 ASSERT(BP_GET_CHECKSUM(bp) == zp->zp_checksum); 3740 ASSERT(BP_IS_HOLE(bp) || zio->io_bp_override); 3741 ASSERT(!(zio->io_bp_override && (zio->io_flags & ZIO_FLAG_RAW))); 3742 /* 3743 * Deduplication will not take place for Direct I/O writes. The 3744 * ddt_tree will be emptied in syncing context. Direct I/O writes take 3745 * place in the open-context. Direct I/O write can not attempt to 3746 * modify the ddt_tree while issuing out a write. 3747 */ 3748 ASSERT3B(zio->io_prop.zp_direct_write, ==, B_FALSE); 3749 3750 ddt_enter(ddt); 3751 /* 3752 * Search DDT for matching entry. Skip DVAs verification here, since 3753 * they can go only from override, and once we get here the override 3754 * pointer can't have "D" flag to be confused with pruned DDT entries. 3755 */ 3756 IMPLY(zio->io_bp_override, !BP_GET_DEDUP(zio->io_bp_override)); 3757 dde = ddt_lookup(ddt, bp, B_FALSE); 3758 if (dde == NULL) { 3759 /* DDT size is over its quota so no new entries */ 3760 zp->zp_dedup = B_FALSE; 3761 BP_SET_DEDUP(bp, B_FALSE); 3762 if (zio->io_bp_override == NULL) 3763 zio->io_pipeline = ZIO_WRITE_PIPELINE; 3764 ddt_exit(ddt); 3765 return (zio); 3766 } 3767 3768 if (zp->zp_dedup_verify && zio_ddt_collision(zio, ddt, dde)) { 3769 /* 3770 * If we're using a weak checksum, upgrade to a strong checksum 3771 * and try again. If we're already using a strong checksum, 3772 * we can't resolve it, so just convert to an ordinary write. 3773 * (And automatically e-mail a paper to Nature?) 3774 */ 3775 if (!(zio_checksum_table[zp->zp_checksum].ci_flags & 3776 ZCHECKSUM_FLAG_DEDUP)) { 3777 zp->zp_checksum = spa_dedup_checksum(spa); 3778 zio_pop_transforms(zio); 3779 zio->io_stage = ZIO_STAGE_OPEN; 3780 BP_ZERO(bp); 3781 } else { 3782 zp->zp_dedup = B_FALSE; 3783 BP_SET_DEDUP(bp, B_FALSE); 3784 } 3785 ASSERT(!BP_GET_DEDUP(bp)); 3786 zio->io_pipeline = ZIO_WRITE_PIPELINE; 3787 ddt_exit(ddt); 3788 return (zio); 3789 } 3790 3791 int p = DDT_PHYS_FOR_COPIES(ddt, zp->zp_copies); 3792 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3793 ddt_univ_phys_t *ddp = dde->dde_phys; 3794 3795 /* 3796 * In the common cases, at this point we have a regular BP with no 3797 * allocated DVAs, and the corresponding DDT entry for its checksum. 3798 * Our goal is to fill the BP with enough DVAs to satisfy its copies= 3799 * requirement. 3800 * 3801 * One of three things needs to happen to fulfill this: 3802 * 3803 * - if the DDT entry has enough DVAs to satisfy the BP, we just copy 3804 * them out of the entry and return; 3805 * 3806 * - if the DDT entry has no DVAs (ie its brand new), then we have to 3807 * issue the write as normal so that DVAs can be allocated and the 3808 * data land on disk. We then copy the DVAs into the DDT entry on 3809 * return. 3810 * 3811 * - if the DDT entry has some DVAs, but too few, we have to issue the 3812 * write, adjusted to have allocate fewer copies. When it returns, we 3813 * add the new DVAs to the DDT entry, and update the BP to have the 3814 * full amount it originally requested. 3815 * 3816 * In all cases, if there's already a writing IO in flight, we need to 3817 * defer the action until after the write is done. If our action is to 3818 * write, we need to adjust our request for additional DVAs to match 3819 * what will be in the DDT entry after it completes. In this way every 3820 * IO can be guaranteed to recieve enough DVAs simply by joining the 3821 * end of the chain and letting the sequence play out. 3822 */ 3823 3824 /* 3825 * Number of DVAs in the DDT entry. If the BP is encrypted we ignore 3826 * the third one as normal. 3827 */ 3828 int have_dvas = ddt_phys_dva_count(ddp, v, BP_IS_ENCRYPTED(bp)); 3829 IMPLY(have_dvas == 0, ddt_phys_birth(ddp, v) == 0); 3830 boolean_t is_ganged = ddt_phys_is_gang(ddp, v); 3831 3832 /* Number of DVAs requested by the IO. */ 3833 uint8_t need_dvas = zp->zp_copies; 3834 /* Number of DVAs in outstanding writes for this dde. */ 3835 uint8_t parent_dvas = 0; 3836 3837 /* 3838 * What we do next depends on whether or not there's IO outstanding that 3839 * will update this entry. 3840 */ 3841 if (dde->dde_io == NULL || dde->dde_io->dde_lead_zio[p] == NULL) { 3842 /* 3843 * No IO outstanding, so we only need to worry about ourselves. 3844 */ 3845 3846 /* 3847 * Override BPs bring their own DVAs and their own problems. 3848 */ 3849 if (zio->io_bp_override) { 3850 /* 3851 * For a brand-new entry, all the work has been done 3852 * for us, and we can just fill it out from the provided 3853 * block and leave. 3854 */ 3855 if (have_dvas == 0) { 3856 ASSERT(BP_GET_LOGICAL_BIRTH(bp) == txg); 3857 ASSERT(BP_EQUAL(bp, zio->io_bp_override)); 3858 ddt_phys_extend(ddp, v, bp); 3859 ddt_phys_addref(ddp, v); 3860 ddt_exit(ddt); 3861 return (zio); 3862 } 3863 3864 /* 3865 * If we already have this entry, then we want to treat 3866 * it like a regular write. To do this we just wipe 3867 * them out and proceed like a regular write. 3868 * 3869 * Even if there are some DVAs in the entry, we still 3870 * have to clear them out. We can't use them to fill 3871 * out the dedup entry, as they are all referenced 3872 * together by a bp already on disk, and will be freed 3873 * as a group. 3874 */ 3875 BP_ZERO_DVAS(bp); 3876 BP_SET_BIRTH(bp, 0, 0); 3877 } 3878 3879 /* 3880 * If there are enough DVAs in the entry to service our request, 3881 * then we can just use them as-is. 3882 */ 3883 if (have_dvas >= need_dvas) { 3884 ddt_bp_fill(ddp, v, bp, txg); 3885 ddt_phys_addref(ddp, v); 3886 ddt_exit(ddt); 3887 return (zio); 3888 } 3889 3890 /* 3891 * Otherwise, we have to issue IO to fill the entry up to the 3892 * amount we need. 3893 */ 3894 need_dvas -= have_dvas; 3895 } else { 3896 /* 3897 * There's a write in-flight. If there's already enough DVAs on 3898 * the entry, then either there were already enough to start 3899 * with, or the in-flight IO is between READY and DONE, and so 3900 * has extended the entry with new DVAs. Either way, we don't 3901 * need to do anything, we can just slot in behind it. 3902 */ 3903 3904 if (zio->io_bp_override) { 3905 /* 3906 * If there's a write out, then we're soon going to 3907 * have our own copies of this block, so clear out the 3908 * override block and treat it as a regular dedup 3909 * write. See comment above. 3910 */ 3911 BP_ZERO_DVAS(bp); 3912 BP_SET_BIRTH(bp, 0, 0); 3913 } 3914 3915 if (have_dvas >= need_dvas) { 3916 /* 3917 * A minor point: there might already be enough 3918 * committed DVAs in the entry to service our request, 3919 * but we don't know which are completed and which are 3920 * allocated but not yet written. In this case, should 3921 * the IO for the new DVAs fail, we will be on the end 3922 * of the IO chain and will also recieve an error, even 3923 * though our request could have been serviced. 3924 * 3925 * This is an extremely rare case, as it requires the 3926 * original block to be copied with a request for a 3927 * larger number of DVAs, then copied again requesting 3928 * the same (or already fulfilled) number of DVAs while 3929 * the first request is active, and then that first 3930 * request errors. In return, the logic required to 3931 * catch and handle it is complex. For now, I'm just 3932 * not going to bother with it. 3933 */ 3934 3935 /* 3936 * We always fill the bp here as we may have arrived 3937 * after the in-flight write has passed READY, and so 3938 * missed out. 3939 */ 3940 ddt_bp_fill(ddp, v, bp, txg); 3941 zio_add_child(zio, dde->dde_io->dde_lead_zio[p]); 3942 ddt_exit(ddt); 3943 return (zio); 3944 } 3945 3946 /* 3947 * There's not enough in the entry yet, so we need to look at 3948 * the write in-flight and see how many DVAs it will have once 3949 * it completes. 3950 * 3951 * The in-flight write has potentially had its copies request 3952 * reduced (if we're filling out an existing entry), so we need 3953 * to reach in and get the original write to find out what it is 3954 * expecting. 3955 * 3956 * Note that the parent of the lead zio will always have the 3957 * highest zp_copies of any zio in the chain, because ones that 3958 * can be serviced without additional IO are always added to 3959 * the back of the chain. 3960 */ 3961 zio_link_t *zl = NULL; 3962 zio_t *pio = 3963 zio_walk_parents(dde->dde_io->dde_lead_zio[p], &zl); 3964 ASSERT(pio); 3965 parent_dvas = pio->io_prop.zp_copies; 3966 3967 if (parent_dvas >= need_dvas) { 3968 zio_add_child(zio, dde->dde_io->dde_lead_zio[p]); 3969 ddt_exit(ddt); 3970 return (zio); 3971 } 3972 3973 /* 3974 * Still not enough, so we will need to issue to get the 3975 * shortfall. 3976 */ 3977 need_dvas -= parent_dvas; 3978 } 3979 3980 if (is_ganged) { 3981 zp->zp_dedup = B_FALSE; 3982 BP_SET_DEDUP(bp, B_FALSE); 3983 zio->io_pipeline = ZIO_WRITE_PIPELINE; 3984 ddt_exit(ddt); 3985 return (zio); 3986 } 3987 3988 /* 3989 * We need to write. We will create a new write with the copies 3990 * property adjusted to match the number of DVAs we need to need to 3991 * grow the DDT entry by to satisfy the request. 3992 */ 3993 zio_prop_t czp = *zp; 3994 if (have_dvas > 0 || parent_dvas > 0) { 3995 czp.zp_copies = need_dvas; 3996 czp.zp_gang_copies = 0; 3997 } else { 3998 ASSERT3U(czp.zp_copies, ==, need_dvas); 3999 } 4000 4001 zio_t *cio = zio_write(zio, spa, txg, bp, zio->io_orig_abd, 4002 zio->io_orig_size, zio->io_orig_size, &czp, 4003 zio_ddt_child_write_ready, NULL, 4004 zio_ddt_child_write_done, dde, zio->io_priority, 4005 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark); 4006 4007 zio_push_transform(cio, zio->io_abd, zio->io_size, 0, NULL); 4008 4009 /* 4010 * We are the new lead zio, because our parent has the highest 4011 * zp_copies that has been requested for this entry so far. 4012 */ 4013 ddt_alloc_entry_io(dde); 4014 if (dde->dde_io->dde_lead_zio[p] == NULL) { 4015 /* 4016 * First time out, take a copy of the stable entry to revert 4017 * to if there's an error (see zio_ddt_child_write_done()) 4018 */ 4019 ddt_phys_copy(&dde->dde_io->dde_orig_phys, dde->dde_phys, v); 4020 } else { 4021 /* 4022 * Make the existing chain our child, because it cannot 4023 * complete until we have. 4024 */ 4025 zio_add_child(cio, dde->dde_io->dde_lead_zio[p]); 4026 } 4027 dde->dde_io->dde_lead_zio[p] = cio; 4028 4029 ddt_exit(ddt); 4030 4031 zio_nowait(cio); 4032 4033 return (zio); 4034 } 4035 4036 static ddt_entry_t *freedde; /* for debugging */ 4037 4038 static zio_t * 4039 zio_ddt_free(zio_t *zio) 4040 { 4041 spa_t *spa = zio->io_spa; 4042 blkptr_t *bp = zio->io_bp; 4043 ddt_t *ddt = ddt_select(spa, bp); 4044 ddt_entry_t *dde = NULL; 4045 4046 ASSERT(BP_GET_DEDUP(bp)); 4047 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 4048 4049 ddt_enter(ddt); 4050 freedde = dde = ddt_lookup(ddt, bp, B_TRUE); 4051 if (dde) { 4052 ddt_phys_variant_t v = ddt_phys_select(ddt, dde, bp); 4053 if (v != DDT_PHYS_NONE) 4054 ddt_phys_decref(dde->dde_phys, v); 4055 } 4056 ddt_exit(ddt); 4057 4058 /* 4059 * When no entry was found, it must have been pruned, 4060 * so we can free it now instead of decrementing the 4061 * refcount in the DDT. 4062 */ 4063 if (!dde) { 4064 BP_SET_DEDUP(bp, 0); 4065 zio->io_pipeline |= ZIO_STAGE_DVA_FREE; 4066 } 4067 4068 return (zio); 4069 } 4070 4071 /* 4072 * ========================================================================== 4073 * Allocate and free blocks 4074 * ========================================================================== 4075 */ 4076 4077 static zio_t * 4078 zio_io_to_allocate(metaslab_class_allocator_t *mca, boolean_t *more) 4079 { 4080 zio_t *zio; 4081 4082 ASSERT(MUTEX_HELD(&mca->mca_lock)); 4083 4084 zio = avl_first(&mca->mca_tree); 4085 if (zio == NULL) { 4086 *more = B_FALSE; 4087 return (NULL); 4088 } 4089 4090 ASSERT(IO_IS_ALLOCATING(zio)); 4091 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 4092 4093 /* 4094 * Try to place a reservation for this zio. If we're unable to 4095 * reserve then we throttle. 4096 */ 4097 if (!metaslab_class_throttle_reserve(zio->io_metaslab_class, 4098 zio->io_prop.zp_copies, zio, B_FALSE, more)) { 4099 return (NULL); 4100 } 4101 4102 avl_remove(&mca->mca_tree, zio); 4103 ASSERT3U(zio->io_stage, <, ZIO_STAGE_DVA_ALLOCATE); 4104 4105 if (avl_is_empty(&mca->mca_tree)) 4106 *more = B_FALSE; 4107 return (zio); 4108 } 4109 4110 static zio_t * 4111 zio_dva_throttle(zio_t *zio) 4112 { 4113 spa_t *spa = zio->io_spa; 4114 zio_t *nio; 4115 metaslab_class_t *mc; 4116 boolean_t more; 4117 4118 /* 4119 * If not already chosen, choose an appropriate allocation class. 4120 */ 4121 mc = zio->io_metaslab_class; 4122 if (mc == NULL) 4123 mc = spa_preferred_class(spa, zio); 4124 4125 if (zio->io_priority == ZIO_PRIORITY_SYNC_WRITE || 4126 !mc->mc_alloc_throttle_enabled || 4127 zio->io_child_type == ZIO_CHILD_GANG || 4128 zio->io_flags & ZIO_FLAG_NODATA) { 4129 return (zio); 4130 } 4131 4132 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 4133 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 4134 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 4135 ASSERT3U(zio->io_queued_timestamp, >, 0); 4136 ASSERT(zio->io_stage == ZIO_STAGE_DVA_THROTTLE); 4137 4138 zio->io_metaslab_class = mc; 4139 metaslab_class_allocator_t *mca = &mc->mc_allocator[zio->io_allocator]; 4140 mutex_enter(&mca->mca_lock); 4141 avl_add(&mca->mca_tree, zio); 4142 nio = zio_io_to_allocate(mca, &more); 4143 mutex_exit(&mca->mca_lock); 4144 return (nio); 4145 } 4146 4147 static void 4148 zio_allocate_dispatch(metaslab_class_t *mc, int allocator) 4149 { 4150 metaslab_class_allocator_t *mca = &mc->mc_allocator[allocator]; 4151 zio_t *zio; 4152 boolean_t more; 4153 4154 do { 4155 mutex_enter(&mca->mca_lock); 4156 zio = zio_io_to_allocate(mca, &more); 4157 mutex_exit(&mca->mca_lock); 4158 if (zio == NULL) 4159 return; 4160 4161 ASSERT3U(zio->io_stage, ==, ZIO_STAGE_DVA_THROTTLE); 4162 ASSERT0(zio->io_error); 4163 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_TRUE); 4164 } while (more); 4165 } 4166 4167 static zio_t * 4168 zio_dva_allocate(zio_t *zio) 4169 { 4170 spa_t *spa = zio->io_spa; 4171 metaslab_class_t *mc; 4172 blkptr_t *bp = zio->io_bp; 4173 int error; 4174 int flags = 0; 4175 4176 if (zio->io_gang_leader == NULL) { 4177 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 4178 zio->io_gang_leader = zio; 4179 } 4180 if (zio->io_flags & ZIO_FLAG_PREALLOCATED) { 4181 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_GANG); 4182 memcpy(zio->io_bp->blk_dva, zio->io_bp_orig.blk_dva, 4183 3 * sizeof (dva_t)); 4184 BP_SET_BIRTH(zio->io_bp, BP_GET_LOGICAL_BIRTH(&zio->io_bp_orig), 4185 BP_GET_PHYSICAL_BIRTH(&zio->io_bp_orig)); 4186 return (zio); 4187 } 4188 4189 ASSERT(BP_IS_HOLE(bp)); 4190 ASSERT0(BP_GET_NDVAS(bp)); 4191 ASSERT3U(zio->io_prop.zp_copies, >, 0); 4192 4193 ASSERT3U(zio->io_prop.zp_copies, <=, spa_max_replication(spa)); 4194 ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp)); 4195 4196 if (zio->io_flags & ZIO_FLAG_GANG_CHILD) 4197 flags |= METASLAB_GANG_CHILD; 4198 if (zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE) 4199 flags |= METASLAB_ASYNC_ALLOC; 4200 4201 /* 4202 * If not already chosen, choose an appropriate allocation class. 4203 */ 4204 mc = zio->io_metaslab_class; 4205 if (mc == NULL) { 4206 mc = spa_preferred_class(spa, zio); 4207 zio->io_metaslab_class = mc; 4208 } 4209 ZIOSTAT_BUMP(ziostat_total_allocations); 4210 4211 again: 4212 /* 4213 * Try allocating the block in the usual metaslab class. 4214 * If that's full, allocate it in the normal class. 4215 * If that's full, allocate as a gang block, 4216 * and if all are full, the allocation fails (which shouldn't happen). 4217 * 4218 * Note that we do not fall back on embedded slog (ZIL) space, to 4219 * preserve unfragmented slog space, which is critical for decent 4220 * sync write performance. If a log allocation fails, we will fall 4221 * back to spa_sync() which is abysmal for performance. 4222 */ 4223 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 4224 error = metaslab_alloc(spa, mc, zio->io_size, bp, 4225 zio->io_prop.zp_copies, zio->io_txg, NULL, flags, 4226 &zio->io_alloc_list, zio->io_allocator, zio); 4227 4228 /* 4229 * Fallback to normal class when an alloc class is full 4230 */ 4231 if (error == ENOSPC && mc != spa_normal_class(spa)) { 4232 /* 4233 * When the dedup or special class is spilling into the normal 4234 * class, there can still be significant space available due 4235 * to deferred frees that are in-flight. We track the txg when 4236 * this occurred and back off adding new DDT entries for a few 4237 * txgs to allow the free blocks to be processed. 4238 */ 4239 if ((mc == spa_dedup_class(spa) || (spa_special_has_ddt(spa) && 4240 mc == spa_special_class(spa))) && 4241 spa->spa_dedup_class_full_txg != zio->io_txg) { 4242 spa->spa_dedup_class_full_txg = zio->io_txg; 4243 zfs_dbgmsg("%s[%d]: %s class spilling, req size %d, " 4244 "%llu allocated of %llu", 4245 spa_name(spa), (int)zio->io_txg, 4246 mc == spa_dedup_class(spa) ? "dedup" : "special", 4247 (int)zio->io_size, 4248 (u_longlong_t)metaslab_class_get_alloc(mc), 4249 (u_longlong_t)metaslab_class_get_space(mc)); 4250 } 4251 4252 /* 4253 * If we are holding old class reservation, drop it. 4254 * Dispatch the next ZIO(s) there if some are waiting. 4255 */ 4256 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 4257 if (metaslab_class_throttle_unreserve(mc, 4258 zio->io_prop.zp_copies, zio)) { 4259 zio_allocate_dispatch(zio->io_metaslab_class, 4260 zio->io_allocator); 4261 } 4262 zio->io_flags &= ~ZIO_FLAG_IO_ALLOCATING; 4263 } 4264 4265 if (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC) { 4266 zfs_dbgmsg("%s: metaslab allocation failure, " 4267 "trying normal class: zio %px, size %llu, error %d", 4268 spa_name(spa), zio, (u_longlong_t)zio->io_size, 4269 error); 4270 } 4271 zio->io_metaslab_class = mc = spa_normal_class(spa); 4272 ZIOSTAT_BUMP(ziostat_alloc_class_fallbacks); 4273 4274 /* 4275 * If normal class uses throttling, return to that pipeline 4276 * stage. Otherwise just do another allocation attempt. 4277 */ 4278 if (zio->io_priority != ZIO_PRIORITY_SYNC_WRITE && 4279 mc->mc_alloc_throttle_enabled && 4280 zio->io_child_type != ZIO_CHILD_GANG && 4281 !(zio->io_flags & ZIO_FLAG_NODATA)) { 4282 zio->io_stage = ZIO_STAGE_DVA_THROTTLE >> 1; 4283 return (zio); 4284 } 4285 goto again; 4286 } 4287 4288 if (error == ENOSPC && zio->io_size > spa->spa_min_alloc) { 4289 if (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC) { 4290 zfs_dbgmsg("%s: metaslab allocation failure, " 4291 "trying ganging: zio %px, size %llu, error %d", 4292 spa_name(spa), zio, (u_longlong_t)zio->io_size, 4293 error); 4294 } 4295 ZIOSTAT_BUMP(ziostat_gang_writes); 4296 if (flags & METASLAB_GANG_CHILD) 4297 ZIOSTAT_BUMP(ziostat_gang_multilevel); 4298 return (zio_write_gang_block(zio, mc)); 4299 } 4300 if (error != 0) { 4301 if (error != ENOSPC || 4302 (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC)) { 4303 zfs_dbgmsg("%s: metaslab allocation failure: zio %px, " 4304 "size %llu, error %d", 4305 spa_name(spa), zio, (u_longlong_t)zio->io_size, 4306 error); 4307 } 4308 zio->io_error = error; 4309 } 4310 4311 return (zio); 4312 } 4313 4314 static zio_t * 4315 zio_dva_free(zio_t *zio) 4316 { 4317 metaslab_free(zio->io_spa, zio->io_bp, zio->io_txg, B_FALSE); 4318 4319 return (zio); 4320 } 4321 4322 static zio_t * 4323 zio_dva_claim(zio_t *zio) 4324 { 4325 int error; 4326 4327 error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg); 4328 if (error) 4329 zio->io_error = error; 4330 4331 return (zio); 4332 } 4333 4334 /* 4335 * Undo an allocation. This is used by zio_done() when an I/O fails 4336 * and we want to give back the block we just allocated. 4337 * This handles both normal blocks and gang blocks. 4338 */ 4339 static void 4340 zio_dva_unallocate(zio_t *zio, zio_gang_node_t *gn, blkptr_t *bp) 4341 { 4342 ASSERT(BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg || BP_IS_HOLE(bp)); 4343 ASSERT(zio->io_bp_override == NULL); 4344 4345 if (!BP_IS_HOLE(bp)) { 4346 metaslab_free(zio->io_spa, bp, BP_GET_LOGICAL_BIRTH(bp), 4347 B_TRUE); 4348 } 4349 4350 if (gn != NULL) { 4351 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 4352 zio_dva_unallocate(zio, gn->gn_child[g], 4353 &gn->gn_gbh->zg_blkptr[g]); 4354 } 4355 } 4356 } 4357 4358 /* 4359 * Try to allocate an intent log block. Return 0 on success, errno on failure. 4360 */ 4361 int 4362 zio_alloc_zil(spa_t *spa, objset_t *os, uint64_t txg, blkptr_t *new_bp, 4363 uint64_t size, boolean_t *slog) 4364 { 4365 int error = 1; 4366 zio_alloc_list_t io_alloc_list; 4367 4368 ASSERT(txg > spa_syncing_txg(spa)); 4369 4370 metaslab_trace_init(&io_alloc_list); 4371 4372 /* 4373 * Block pointer fields are useful to metaslabs for stats and debugging. 4374 * Fill in the obvious ones before calling into metaslab_alloc(). 4375 */ 4376 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG); 4377 BP_SET_PSIZE(new_bp, size); 4378 BP_SET_LEVEL(new_bp, 0); 4379 4380 /* 4381 * When allocating a zil block, we don't have information about 4382 * the final destination of the block except the objset it's part 4383 * of, so we just hash the objset ID to pick the allocator to get 4384 * some parallelism. 4385 */ 4386 int flags = METASLAB_ZIL; 4387 int allocator = (uint_t)cityhash1(os->os_dsl_dataset->ds_object) 4388 % spa->spa_alloc_count; 4389 ZIOSTAT_BUMP(ziostat_total_allocations); 4390 error = metaslab_alloc(spa, spa_log_class(spa), size, new_bp, 1, 4391 txg, NULL, flags, &io_alloc_list, allocator, NULL); 4392 *slog = (error == 0); 4393 if (error != 0) { 4394 error = metaslab_alloc(spa, spa_embedded_log_class(spa), size, 4395 new_bp, 1, txg, NULL, flags, &io_alloc_list, allocator, 4396 NULL); 4397 } 4398 if (error != 0) { 4399 ZIOSTAT_BUMP(ziostat_alloc_class_fallbacks); 4400 error = metaslab_alloc(spa, spa_normal_class(spa), size, 4401 new_bp, 1, txg, NULL, flags, &io_alloc_list, allocator, 4402 NULL); 4403 } 4404 metaslab_trace_fini(&io_alloc_list); 4405 4406 if (error == 0) { 4407 BP_SET_LSIZE(new_bp, size); 4408 BP_SET_PSIZE(new_bp, size); 4409 BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF); 4410 BP_SET_CHECKSUM(new_bp, 4411 spa_version(spa) >= SPA_VERSION_SLIM_ZIL 4412 ? ZIO_CHECKSUM_ZILOG2 : ZIO_CHECKSUM_ZILOG); 4413 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG); 4414 BP_SET_LEVEL(new_bp, 0); 4415 BP_SET_DEDUP(new_bp, 0); 4416 BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER); 4417 4418 /* 4419 * encrypted blocks will require an IV and salt. We generate 4420 * these now since we will not be rewriting the bp at 4421 * rewrite time. 4422 */ 4423 if (os->os_encrypted) { 4424 uint8_t iv[ZIO_DATA_IV_LEN]; 4425 uint8_t salt[ZIO_DATA_SALT_LEN]; 4426 4427 BP_SET_CRYPT(new_bp, B_TRUE); 4428 VERIFY0(spa_crypt_get_salt(spa, 4429 dmu_objset_id(os), salt)); 4430 VERIFY0(zio_crypt_generate_iv(iv)); 4431 4432 zio_crypt_encode_params_bp(new_bp, salt, iv); 4433 } 4434 } else { 4435 zfs_dbgmsg("%s: zil block allocation failure: " 4436 "size %llu, error %d", spa_name(spa), (u_longlong_t)size, 4437 error); 4438 } 4439 4440 return (error); 4441 } 4442 4443 /* 4444 * ========================================================================== 4445 * Read and write to physical devices 4446 * ========================================================================== 4447 */ 4448 4449 /* 4450 * Issue an I/O to the underlying vdev. Typically the issue pipeline 4451 * stops after this stage and will resume upon I/O completion. 4452 * However, there are instances where the vdev layer may need to 4453 * continue the pipeline when an I/O was not issued. Since the I/O 4454 * that was sent to the vdev layer might be different than the one 4455 * currently active in the pipeline (see vdev_queue_io()), we explicitly 4456 * force the underlying vdev layers to call either zio_execute() or 4457 * zio_interrupt() to ensure that the pipeline continues with the correct I/O. 4458 */ 4459 static zio_t * 4460 zio_vdev_io_start(zio_t *zio) 4461 { 4462 vdev_t *vd = zio->io_vd; 4463 uint64_t align; 4464 spa_t *spa = zio->io_spa; 4465 4466 zio->io_delay = 0; 4467 4468 ASSERT(zio->io_error == 0); 4469 ASSERT(zio->io_child_error[ZIO_CHILD_VDEV] == 0); 4470 4471 if (vd == NULL) { 4472 if (!(zio->io_flags & ZIO_FLAG_CONFIG_WRITER)) 4473 spa_config_enter(spa, SCL_ZIO, zio, RW_READER); 4474 4475 /* 4476 * The mirror_ops handle multiple DVAs in a single BP. 4477 */ 4478 vdev_mirror_ops.vdev_op_io_start(zio); 4479 return (NULL); 4480 } 4481 4482 ASSERT3P(zio->io_logical, !=, zio); 4483 if (zio->io_type == ZIO_TYPE_WRITE) { 4484 ASSERT(spa->spa_trust_config); 4485 4486 /* 4487 * Note: the code can handle other kinds of writes, 4488 * but we don't expect them. 4489 */ 4490 if (zio->io_vd->vdev_noalloc) { 4491 ASSERT(zio->io_flags & 4492 (ZIO_FLAG_PHYSICAL | ZIO_FLAG_SELF_HEAL | 4493 ZIO_FLAG_RESILVER | ZIO_FLAG_INDUCE_DAMAGE)); 4494 } 4495 } 4496 4497 align = 1ULL << vd->vdev_top->vdev_ashift; 4498 4499 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL) && 4500 P2PHASE(zio->io_size, align) != 0) { 4501 /* Transform logical writes to be a full physical block size. */ 4502 uint64_t asize = P2ROUNDUP(zio->io_size, align); 4503 abd_t *abuf = abd_alloc_sametype(zio->io_abd, asize); 4504 ASSERT(vd == vd->vdev_top); 4505 if (zio->io_type == ZIO_TYPE_WRITE) { 4506 abd_copy(abuf, zio->io_abd, zio->io_size); 4507 abd_zero_off(abuf, zio->io_size, asize - zio->io_size); 4508 } 4509 zio_push_transform(zio, abuf, asize, asize, zio_subblock); 4510 } 4511 4512 /* 4513 * If this is not a physical io, make sure that it is properly aligned 4514 * before proceeding. 4515 */ 4516 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL)) { 4517 ASSERT0(P2PHASE(zio->io_offset, align)); 4518 ASSERT0(P2PHASE(zio->io_size, align)); 4519 } else { 4520 /* 4521 * For physical writes, we allow 512b aligned writes and assume 4522 * the device will perform a read-modify-write as necessary. 4523 */ 4524 ASSERT0(P2PHASE(zio->io_offset, SPA_MINBLOCKSIZE)); 4525 ASSERT0(P2PHASE(zio->io_size, SPA_MINBLOCKSIZE)); 4526 } 4527 4528 VERIFY(zio->io_type != ZIO_TYPE_WRITE || spa_writeable(spa)); 4529 4530 /* 4531 * If this is a repair I/O, and there's no self-healing involved -- 4532 * that is, we're just resilvering what we expect to resilver -- 4533 * then don't do the I/O unless zio's txg is actually in vd's DTL. 4534 * This prevents spurious resilvering. 4535 * 4536 * There are a few ways that we can end up creating these spurious 4537 * resilver i/os: 4538 * 4539 * 1. A resilver i/o will be issued if any DVA in the BP has a 4540 * dirty DTL. The mirror code will issue resilver writes to 4541 * each DVA, including the one(s) that are not on vdevs with dirty 4542 * DTLs. 4543 * 4544 * 2. With nested replication, which happens when we have a 4545 * "replacing" or "spare" vdev that's a child of a mirror or raidz. 4546 * For example, given mirror(replacing(A+B), C), it's likely that 4547 * only A is out of date (it's the new device). In this case, we'll 4548 * read from C, then use the data to resilver A+B -- but we don't 4549 * actually want to resilver B, just A. The top-level mirror has no 4550 * way to know this, so instead we just discard unnecessary repairs 4551 * as we work our way down the vdev tree. 4552 * 4553 * 3. ZTEST also creates mirrors of mirrors, mirrors of raidz, etc. 4554 * The same logic applies to any form of nested replication: ditto 4555 * + mirror, RAID-Z + replacing, etc. 4556 * 4557 * However, indirect vdevs point off to other vdevs which may have 4558 * DTL's, so we never bypass them. The child i/os on concrete vdevs 4559 * will be properly bypassed instead. 4560 * 4561 * Leaf DTL_PARTIAL can be empty when a legitimate write comes from 4562 * a dRAID spare vdev. For example, when a dRAID spare is first 4563 * used, its spare blocks need to be written to but the leaf vdev's 4564 * of such blocks can have empty DTL_PARTIAL. 4565 * 4566 * There seemed no clean way to allow such writes while bypassing 4567 * spurious ones. At this point, just avoid all bypassing for dRAID 4568 * for correctness. 4569 */ 4570 if ((zio->io_flags & ZIO_FLAG_IO_REPAIR) && 4571 !(zio->io_flags & ZIO_FLAG_SELF_HEAL) && 4572 zio->io_txg != 0 && /* not a delegated i/o */ 4573 vd->vdev_ops != &vdev_indirect_ops && 4574 vd->vdev_top->vdev_ops != &vdev_draid_ops && 4575 !vdev_dtl_contains(vd, DTL_PARTIAL, zio->io_txg, 1)) { 4576 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 4577 zio_vdev_io_bypass(zio); 4578 return (zio); 4579 } 4580 4581 /* 4582 * Select the next best leaf I/O to process. Distributed spares are 4583 * excluded since they dispatch the I/O directly to a leaf vdev after 4584 * applying the dRAID mapping. 4585 */ 4586 if (vd->vdev_ops->vdev_op_leaf && 4587 vd->vdev_ops != &vdev_draid_spare_ops && 4588 (zio->io_type == ZIO_TYPE_READ || 4589 zio->io_type == ZIO_TYPE_WRITE || 4590 zio->io_type == ZIO_TYPE_TRIM)) { 4591 4592 if ((zio = vdev_queue_io(zio)) == NULL) 4593 return (NULL); 4594 4595 if (!vdev_accessible(vd, zio)) { 4596 zio->io_error = SET_ERROR(ENXIO); 4597 zio_interrupt(zio); 4598 return (NULL); 4599 } 4600 zio->io_delay = gethrtime(); 4601 4602 if (zio_handle_device_injection(vd, zio, ENOSYS) != 0) { 4603 /* 4604 * "no-op" injections return success, but do no actual 4605 * work. Just return it. 4606 */ 4607 zio_delay_interrupt(zio); 4608 return (NULL); 4609 } 4610 } 4611 4612 vd->vdev_ops->vdev_op_io_start(zio); 4613 return (NULL); 4614 } 4615 4616 static zio_t * 4617 zio_vdev_io_done(zio_t *zio) 4618 { 4619 vdev_t *vd = zio->io_vd; 4620 vdev_ops_t *ops = vd ? vd->vdev_ops : &vdev_mirror_ops; 4621 boolean_t unexpected_error = B_FALSE; 4622 4623 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV_BIT, ZIO_WAIT_DONE)) { 4624 return (NULL); 4625 } 4626 4627 ASSERT(zio->io_type == ZIO_TYPE_READ || 4628 zio->io_type == ZIO_TYPE_WRITE || 4629 zio->io_type == ZIO_TYPE_FLUSH || 4630 zio->io_type == ZIO_TYPE_TRIM); 4631 4632 if (zio->io_delay) 4633 zio->io_delay = gethrtime() - zio->io_delay; 4634 4635 if (vd != NULL && vd->vdev_ops->vdev_op_leaf && 4636 vd->vdev_ops != &vdev_draid_spare_ops) { 4637 if (zio->io_type != ZIO_TYPE_FLUSH) 4638 vdev_queue_io_done(zio); 4639 4640 if (zio_injection_enabled && zio->io_error == 0) 4641 zio->io_error = zio_handle_device_injections(vd, zio, 4642 EIO, EILSEQ); 4643 4644 if (zio_injection_enabled && zio->io_error == 0) 4645 zio->io_error = zio_handle_label_injection(zio, EIO); 4646 4647 if (zio->io_error && zio->io_type != ZIO_TYPE_FLUSH && 4648 zio->io_type != ZIO_TYPE_TRIM) { 4649 if (!vdev_accessible(vd, zio)) { 4650 zio->io_error = SET_ERROR(ENXIO); 4651 } else { 4652 unexpected_error = B_TRUE; 4653 } 4654 } 4655 } 4656 4657 ops->vdev_op_io_done(zio); 4658 4659 if (unexpected_error && vd->vdev_remove_wanted == B_FALSE) 4660 VERIFY(vdev_probe(vd, zio) == NULL); 4661 4662 return (zio); 4663 } 4664 4665 /* 4666 * This function is used to change the priority of an existing zio that is 4667 * currently in-flight. This is used by the arc to upgrade priority in the 4668 * event that a demand read is made for a block that is currently queued 4669 * as a scrub or async read IO. Otherwise, the high priority read request 4670 * would end up having to wait for the lower priority IO. 4671 */ 4672 void 4673 zio_change_priority(zio_t *pio, zio_priority_t priority) 4674 { 4675 zio_t *cio, *cio_next; 4676 zio_link_t *zl = NULL; 4677 4678 ASSERT3U(priority, <, ZIO_PRIORITY_NUM_QUEUEABLE); 4679 4680 if (pio->io_vd != NULL && pio->io_vd->vdev_ops->vdev_op_leaf) { 4681 vdev_queue_change_io_priority(pio, priority); 4682 } else { 4683 pio->io_priority = priority; 4684 } 4685 4686 mutex_enter(&pio->io_lock); 4687 for (cio = zio_walk_children(pio, &zl); cio != NULL; cio = cio_next) { 4688 cio_next = zio_walk_children(pio, &zl); 4689 zio_change_priority(cio, priority); 4690 } 4691 mutex_exit(&pio->io_lock); 4692 } 4693 4694 /* 4695 * For non-raidz ZIOs, we can just copy aside the bad data read from the 4696 * disk, and use that to finish the checksum ereport later. 4697 */ 4698 static void 4699 zio_vsd_default_cksum_finish(zio_cksum_report_t *zcr, 4700 const abd_t *good_buf) 4701 { 4702 /* no processing needed */ 4703 zfs_ereport_finish_checksum(zcr, good_buf, zcr->zcr_cbdata, B_FALSE); 4704 } 4705 4706 void 4707 zio_vsd_default_cksum_report(zio_t *zio, zio_cksum_report_t *zcr) 4708 { 4709 void *abd = abd_alloc_sametype(zio->io_abd, zio->io_size); 4710 4711 abd_copy(abd, zio->io_abd, zio->io_size); 4712 4713 zcr->zcr_cbinfo = zio->io_size; 4714 zcr->zcr_cbdata = abd; 4715 zcr->zcr_finish = zio_vsd_default_cksum_finish; 4716 zcr->zcr_free = zio_abd_free; 4717 } 4718 4719 static zio_t * 4720 zio_vdev_io_assess(zio_t *zio) 4721 { 4722 vdev_t *vd = zio->io_vd; 4723 4724 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV_BIT, ZIO_WAIT_DONE)) { 4725 return (NULL); 4726 } 4727 4728 if (vd == NULL && !(zio->io_flags & ZIO_FLAG_CONFIG_WRITER)) 4729 spa_config_exit(zio->io_spa, SCL_ZIO, zio); 4730 4731 if (zio->io_vsd != NULL) { 4732 zio->io_vsd_ops->vsd_free(zio); 4733 zio->io_vsd = NULL; 4734 } 4735 4736 /* 4737 * If a Direct I/O operation has a checksum verify error then this I/O 4738 * should not attempt to be issued again. 4739 */ 4740 if (zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR) { 4741 if (zio->io_type == ZIO_TYPE_WRITE) { 4742 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_LOGICAL); 4743 ASSERT3U(zio->io_error, ==, EIO); 4744 } 4745 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 4746 return (zio); 4747 } 4748 4749 if (zio_injection_enabled && zio->io_error == 0) 4750 zio->io_error = zio_handle_fault_injection(zio, EIO); 4751 4752 /* 4753 * If the I/O failed, determine whether we should attempt to retry it. 4754 * 4755 * On retry, we cut in line in the issue queue, since we don't want 4756 * compression/checksumming/etc. work to prevent our (cheap) IO reissue. 4757 */ 4758 if (zio->io_error && vd == NULL && 4759 !(zio->io_flags & (ZIO_FLAG_DONT_RETRY | ZIO_FLAG_IO_RETRY))) { 4760 ASSERT(!(zio->io_flags & ZIO_FLAG_DONT_QUEUE)); /* not a leaf */ 4761 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_BYPASS)); /* not a leaf */ 4762 zio->io_error = 0; 4763 zio->io_flags |= ZIO_FLAG_IO_RETRY | ZIO_FLAG_DONT_AGGREGATE; 4764 zio->io_stage = ZIO_STAGE_VDEV_IO_START >> 1; 4765 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, 4766 zio_requeue_io_start_cut_in_line); 4767 return (NULL); 4768 } 4769 4770 /* 4771 * If we got an error on a leaf device, convert it to ENXIO 4772 * if the device is not accessible at all. 4773 */ 4774 if (zio->io_error && vd != NULL && vd->vdev_ops->vdev_op_leaf && 4775 !vdev_accessible(vd, zio)) 4776 zio->io_error = SET_ERROR(ENXIO); 4777 4778 /* 4779 * If we can't write to an interior vdev (mirror or RAID-Z), 4780 * set vdev_cant_write so that we stop trying to allocate from it. 4781 */ 4782 if (zio->io_error == ENXIO && zio->io_type == ZIO_TYPE_WRITE && 4783 vd != NULL && !vd->vdev_ops->vdev_op_leaf) { 4784 vdev_dbgmsg(vd, "zio_vdev_io_assess(zio=%px) setting " 4785 "cant_write=TRUE due to write failure with ENXIO", 4786 zio); 4787 vd->vdev_cant_write = B_TRUE; 4788 } 4789 4790 /* 4791 * If a cache flush returns ENOTSUP we know that no future 4792 * attempts will ever succeed. In this case we set a persistent 4793 * boolean flag so that we don't bother with it in the future, and 4794 * then we act like the flush succeeded. 4795 */ 4796 if (zio->io_error == ENOTSUP && zio->io_type == ZIO_TYPE_FLUSH && 4797 vd != NULL) { 4798 vd->vdev_nowritecache = B_TRUE; 4799 zio->io_error = 0; 4800 } 4801 4802 if (zio->io_error) 4803 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 4804 4805 return (zio); 4806 } 4807 4808 void 4809 zio_vdev_io_reissue(zio_t *zio) 4810 { 4811 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START); 4812 ASSERT(zio->io_error == 0); 4813 4814 zio->io_stage >>= 1; 4815 } 4816 4817 void 4818 zio_vdev_io_redone(zio_t *zio) 4819 { 4820 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_DONE); 4821 4822 zio->io_stage >>= 1; 4823 } 4824 4825 void 4826 zio_vdev_io_bypass(zio_t *zio) 4827 { 4828 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START); 4829 ASSERT(zio->io_error == 0); 4830 4831 zio->io_flags |= ZIO_FLAG_IO_BYPASS; 4832 zio->io_stage = ZIO_STAGE_VDEV_IO_ASSESS >> 1; 4833 } 4834 4835 /* 4836 * ========================================================================== 4837 * Encrypt and store encryption parameters 4838 * ========================================================================== 4839 */ 4840 4841 4842 /* 4843 * This function is used for ZIO_STAGE_ENCRYPT. It is responsible for 4844 * managing the storage of encryption parameters and passing them to the 4845 * lower-level encryption functions. 4846 */ 4847 static zio_t * 4848 zio_encrypt(zio_t *zio) 4849 { 4850 zio_prop_t *zp = &zio->io_prop; 4851 spa_t *spa = zio->io_spa; 4852 blkptr_t *bp = zio->io_bp; 4853 uint64_t psize = BP_GET_PSIZE(bp); 4854 uint64_t dsobj = zio->io_bookmark.zb_objset; 4855 dmu_object_type_t ot = BP_GET_TYPE(bp); 4856 void *enc_buf = NULL; 4857 abd_t *eabd = NULL; 4858 uint8_t salt[ZIO_DATA_SALT_LEN]; 4859 uint8_t iv[ZIO_DATA_IV_LEN]; 4860 uint8_t mac[ZIO_DATA_MAC_LEN]; 4861 boolean_t no_crypt = B_FALSE; 4862 4863 /* the root zio already encrypted the data */ 4864 if (zio->io_child_type == ZIO_CHILD_GANG) 4865 return (zio); 4866 4867 /* only ZIL blocks are re-encrypted on rewrite */ 4868 if (!IO_IS_ALLOCATING(zio) && ot != DMU_OT_INTENT_LOG) 4869 return (zio); 4870 4871 if (!(zp->zp_encrypt || BP_IS_ENCRYPTED(bp))) { 4872 BP_SET_CRYPT(bp, B_FALSE); 4873 return (zio); 4874 } 4875 4876 /* if we are doing raw encryption set the provided encryption params */ 4877 if (zio->io_flags & ZIO_FLAG_RAW_ENCRYPT) { 4878 ASSERT0(BP_GET_LEVEL(bp)); 4879 BP_SET_CRYPT(bp, B_TRUE); 4880 BP_SET_BYTEORDER(bp, zp->zp_byteorder); 4881 if (ot != DMU_OT_OBJSET) 4882 zio_crypt_encode_mac_bp(bp, zp->zp_mac); 4883 4884 /* dnode blocks must be written out in the provided byteorder */ 4885 if (zp->zp_byteorder != ZFS_HOST_BYTEORDER && 4886 ot == DMU_OT_DNODE) { 4887 void *bswap_buf = zio_buf_alloc(psize); 4888 abd_t *babd = abd_get_from_buf(bswap_buf, psize); 4889 4890 ASSERT3U(BP_GET_COMPRESS(bp), ==, ZIO_COMPRESS_OFF); 4891 abd_copy_to_buf(bswap_buf, zio->io_abd, psize); 4892 dmu_ot_byteswap[DMU_OT_BYTESWAP(ot)].ob_func(bswap_buf, 4893 psize); 4894 4895 abd_take_ownership_of_buf(babd, B_TRUE); 4896 zio_push_transform(zio, babd, psize, psize, NULL); 4897 } 4898 4899 if (DMU_OT_IS_ENCRYPTED(ot)) 4900 zio_crypt_encode_params_bp(bp, zp->zp_salt, zp->zp_iv); 4901 return (zio); 4902 } 4903 4904 /* indirect blocks only maintain a cksum of the lower level MACs */ 4905 if (BP_GET_LEVEL(bp) > 0) { 4906 BP_SET_CRYPT(bp, B_TRUE); 4907 VERIFY0(zio_crypt_do_indirect_mac_checksum_abd(B_TRUE, 4908 zio->io_orig_abd, BP_GET_LSIZE(bp), BP_SHOULD_BYTESWAP(bp), 4909 mac)); 4910 zio_crypt_encode_mac_bp(bp, mac); 4911 return (zio); 4912 } 4913 4914 /* 4915 * Objset blocks are a special case since they have 2 256-bit MACs 4916 * embedded within them. 4917 */ 4918 if (ot == DMU_OT_OBJSET) { 4919 ASSERT0(DMU_OT_IS_ENCRYPTED(ot)); 4920 ASSERT3U(BP_GET_COMPRESS(bp), ==, ZIO_COMPRESS_OFF); 4921 BP_SET_CRYPT(bp, B_TRUE); 4922 VERIFY0(spa_do_crypt_objset_mac_abd(B_TRUE, spa, dsobj, 4923 zio->io_abd, psize, BP_SHOULD_BYTESWAP(bp))); 4924 return (zio); 4925 } 4926 4927 /* unencrypted object types are only authenticated with a MAC */ 4928 if (!DMU_OT_IS_ENCRYPTED(ot)) { 4929 BP_SET_CRYPT(bp, B_TRUE); 4930 VERIFY0(spa_do_crypt_mac_abd(B_TRUE, spa, dsobj, 4931 zio->io_abd, psize, mac)); 4932 zio_crypt_encode_mac_bp(bp, mac); 4933 return (zio); 4934 } 4935 4936 /* 4937 * Later passes of sync-to-convergence may decide to rewrite data 4938 * in place to avoid more disk reallocations. This presents a problem 4939 * for encryption because this constitutes rewriting the new data with 4940 * the same encryption key and IV. However, this only applies to blocks 4941 * in the MOS (particularly the spacemaps) and we do not encrypt the 4942 * MOS. We assert that the zio is allocating or an intent log write 4943 * to enforce this. 4944 */ 4945 ASSERT(IO_IS_ALLOCATING(zio) || ot == DMU_OT_INTENT_LOG); 4946 ASSERT(BP_GET_LEVEL(bp) == 0 || ot == DMU_OT_INTENT_LOG); 4947 ASSERT(spa_feature_is_active(spa, SPA_FEATURE_ENCRYPTION)); 4948 ASSERT3U(psize, !=, 0); 4949 4950 enc_buf = zio_buf_alloc(psize); 4951 eabd = abd_get_from_buf(enc_buf, psize); 4952 abd_take_ownership_of_buf(eabd, B_TRUE); 4953 4954 /* 4955 * For an explanation of what encryption parameters are stored 4956 * where, see the block comment in zio_crypt.c. 4957 */ 4958 if (ot == DMU_OT_INTENT_LOG) { 4959 zio_crypt_decode_params_bp(bp, salt, iv); 4960 } else { 4961 BP_SET_CRYPT(bp, B_TRUE); 4962 } 4963 4964 /* Perform the encryption. This should not fail */ 4965 VERIFY0(spa_do_crypt_abd(B_TRUE, spa, &zio->io_bookmark, 4966 BP_GET_TYPE(bp), BP_GET_DEDUP(bp), BP_SHOULD_BYTESWAP(bp), 4967 salt, iv, mac, psize, zio->io_abd, eabd, &no_crypt)); 4968 4969 /* encode encryption metadata into the bp */ 4970 if (ot == DMU_OT_INTENT_LOG) { 4971 /* 4972 * ZIL blocks store the MAC in the embedded checksum, so the 4973 * transform must always be applied. 4974 */ 4975 zio_crypt_encode_mac_zil(enc_buf, mac); 4976 zio_push_transform(zio, eabd, psize, psize, NULL); 4977 } else { 4978 BP_SET_CRYPT(bp, B_TRUE); 4979 zio_crypt_encode_params_bp(bp, salt, iv); 4980 zio_crypt_encode_mac_bp(bp, mac); 4981 4982 if (no_crypt) { 4983 ASSERT3U(ot, ==, DMU_OT_DNODE); 4984 abd_free(eabd); 4985 } else { 4986 zio_push_transform(zio, eabd, psize, psize, NULL); 4987 } 4988 } 4989 4990 return (zio); 4991 } 4992 4993 /* 4994 * ========================================================================== 4995 * Generate and verify checksums 4996 * ========================================================================== 4997 */ 4998 static zio_t * 4999 zio_checksum_generate(zio_t *zio) 5000 { 5001 blkptr_t *bp = zio->io_bp; 5002 enum zio_checksum checksum; 5003 5004 if (bp == NULL) { 5005 /* 5006 * This is zio_write_phys(). 5007 * We're either generating a label checksum, or none at all. 5008 */ 5009 checksum = zio->io_prop.zp_checksum; 5010 5011 if (checksum == ZIO_CHECKSUM_OFF) 5012 return (zio); 5013 5014 ASSERT(checksum == ZIO_CHECKSUM_LABEL); 5015 } else { 5016 if (BP_IS_GANG(bp) && zio->io_child_type == ZIO_CHILD_GANG) { 5017 ASSERT(!IO_IS_ALLOCATING(zio)); 5018 checksum = ZIO_CHECKSUM_GANG_HEADER; 5019 } else { 5020 checksum = BP_GET_CHECKSUM(bp); 5021 } 5022 } 5023 5024 zio_checksum_compute(zio, checksum, zio->io_abd, zio->io_size); 5025 5026 return (zio); 5027 } 5028 5029 static zio_t * 5030 zio_checksum_verify(zio_t *zio) 5031 { 5032 zio_bad_cksum_t info; 5033 blkptr_t *bp = zio->io_bp; 5034 int error; 5035 5036 ASSERT(zio->io_vd != NULL); 5037 5038 if (bp == NULL) { 5039 /* 5040 * This is zio_read_phys(). 5041 * We're either verifying a label checksum, or nothing at all. 5042 */ 5043 if (zio->io_prop.zp_checksum == ZIO_CHECKSUM_OFF) 5044 return (zio); 5045 5046 ASSERT3U(zio->io_prop.zp_checksum, ==, ZIO_CHECKSUM_LABEL); 5047 } 5048 5049 ASSERT0(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR); 5050 IMPLY(zio->io_flags & ZIO_FLAG_DIO_READ, 5051 !(zio->io_flags & ZIO_FLAG_SPECULATIVE)); 5052 5053 if ((error = zio_checksum_error(zio, &info)) != 0) { 5054 zio->io_error = error; 5055 if (error == ECKSUM && 5056 !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) { 5057 if (zio->io_flags & ZIO_FLAG_DIO_READ) { 5058 zio->io_flags |= ZIO_FLAG_DIO_CHKSUM_ERR; 5059 zio_t *pio = zio_unique_parent(zio); 5060 /* 5061 * Any Direct I/O read that has a checksum 5062 * error must be treated as suspicous as the 5063 * contents of the buffer could be getting 5064 * manipulated while the I/O is taking place. 5065 * 5066 * The checksum verify error will only be 5067 * reported here for disk and file VDEV's and 5068 * will be reported on those that the failure 5069 * occurred on. Other types of VDEV's report the 5070 * verify failure in their own code paths. 5071 */ 5072 if (pio->io_child_type == ZIO_CHILD_LOGICAL) { 5073 zio_dio_chksum_verify_error_report(zio); 5074 } 5075 } else { 5076 mutex_enter(&zio->io_vd->vdev_stat_lock); 5077 zio->io_vd->vdev_stat.vs_checksum_errors++; 5078 mutex_exit(&zio->io_vd->vdev_stat_lock); 5079 (void) zfs_ereport_start_checksum(zio->io_spa, 5080 zio->io_vd, &zio->io_bookmark, zio, 5081 zio->io_offset, zio->io_size, &info); 5082 } 5083 } 5084 } 5085 5086 return (zio); 5087 } 5088 5089 static zio_t * 5090 zio_dio_checksum_verify(zio_t *zio) 5091 { 5092 zio_t *pio = zio_unique_parent(zio); 5093 int error; 5094 5095 ASSERT3P(zio->io_vd, !=, NULL); 5096 ASSERT3P(zio->io_bp, !=, NULL); 5097 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV); 5098 ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE); 5099 ASSERT3B(pio->io_prop.zp_direct_write, ==, B_TRUE); 5100 ASSERT3U(pio->io_child_type, ==, ZIO_CHILD_LOGICAL); 5101 5102 if (zfs_vdev_direct_write_verify == 0 || zio->io_error != 0) 5103 goto out; 5104 5105 if ((error = zio_checksum_error(zio, NULL)) != 0) { 5106 zio->io_error = error; 5107 if (error == ECKSUM) { 5108 zio->io_flags |= ZIO_FLAG_DIO_CHKSUM_ERR; 5109 zio_dio_chksum_verify_error_report(zio); 5110 } 5111 } 5112 5113 out: 5114 return (zio); 5115 } 5116 5117 5118 /* 5119 * Called by RAID-Z to ensure we don't compute the checksum twice. 5120 */ 5121 void 5122 zio_checksum_verified(zio_t *zio) 5123 { 5124 zio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY; 5125 } 5126 5127 /* 5128 * Report Direct I/O checksum verify error and create ZED event. 5129 */ 5130 void 5131 zio_dio_chksum_verify_error_report(zio_t *zio) 5132 { 5133 ASSERT(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR); 5134 5135 if (zio->io_child_type == ZIO_CHILD_LOGICAL) 5136 return; 5137 5138 mutex_enter(&zio->io_vd->vdev_stat_lock); 5139 zio->io_vd->vdev_stat.vs_dio_verify_errors++; 5140 mutex_exit(&zio->io_vd->vdev_stat_lock); 5141 if (zio->io_type == ZIO_TYPE_WRITE) { 5142 /* 5143 * Convert checksum error for writes into EIO. 5144 */ 5145 zio->io_error = SET_ERROR(EIO); 5146 /* 5147 * Report dio_verify_wr ZED event. 5148 */ 5149 (void) zfs_ereport_post(FM_EREPORT_ZFS_DIO_VERIFY_WR, 5150 zio->io_spa, zio->io_vd, &zio->io_bookmark, zio, 0); 5151 } else { 5152 /* 5153 * Report dio_verify_rd ZED event. 5154 */ 5155 (void) zfs_ereport_post(FM_EREPORT_ZFS_DIO_VERIFY_RD, 5156 zio->io_spa, zio->io_vd, &zio->io_bookmark, zio, 0); 5157 } 5158 } 5159 5160 /* 5161 * ========================================================================== 5162 * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other. 5163 * An error of 0 indicates success. ENXIO indicates whole-device failure, 5164 * which may be transient (e.g. unplugged) or permanent. ECKSUM and EIO 5165 * indicate errors that are specific to one I/O, and most likely permanent. 5166 * Any other error is presumed to be worse because we weren't expecting it. 5167 * ========================================================================== 5168 */ 5169 int 5170 zio_worst_error(int e1, int e2) 5171 { 5172 static int zio_error_rank[] = { 0, ENXIO, ECKSUM, EIO }; 5173 int r1, r2; 5174 5175 for (r1 = 0; r1 < sizeof (zio_error_rank) / sizeof (int); r1++) 5176 if (e1 == zio_error_rank[r1]) 5177 break; 5178 5179 for (r2 = 0; r2 < sizeof (zio_error_rank) / sizeof (int); r2++) 5180 if (e2 == zio_error_rank[r2]) 5181 break; 5182 5183 return (r1 > r2 ? e1 : e2); 5184 } 5185 5186 /* 5187 * ========================================================================== 5188 * I/O completion 5189 * ========================================================================== 5190 */ 5191 static zio_t * 5192 zio_ready(zio_t *zio) 5193 { 5194 blkptr_t *bp = zio->io_bp; 5195 zio_t *pio, *pio_next; 5196 zio_link_t *zl = NULL; 5197 5198 if (zio_wait_for_children(zio, ZIO_CHILD_LOGICAL_BIT | 5199 ZIO_CHILD_GANG_BIT | ZIO_CHILD_DDT_BIT, ZIO_WAIT_READY)) { 5200 return (NULL); 5201 } 5202 5203 if (zio->io_ready) { 5204 ASSERT(IO_IS_ALLOCATING(zio)); 5205 ASSERT(BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg || 5206 BP_IS_HOLE(bp) || (zio->io_flags & ZIO_FLAG_NOPWRITE)); 5207 ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0); 5208 5209 zio->io_ready(zio); 5210 } 5211 5212 #ifdef ZFS_DEBUG 5213 if (bp != NULL && bp != &zio->io_bp_copy) 5214 zio->io_bp_copy = *bp; 5215 #endif 5216 5217 if (zio->io_error != 0) { 5218 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 5219 5220 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 5221 ASSERT(IO_IS_ALLOCATING(zio)); 5222 ASSERT(zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE); 5223 ASSERT(zio->io_metaslab_class != NULL); 5224 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 5225 5226 /* 5227 * We were unable to allocate anything, unreserve and 5228 * issue the next I/O to allocate. 5229 */ 5230 if (metaslab_class_throttle_unreserve( 5231 zio->io_metaslab_class, zio->io_prop.zp_copies, 5232 zio)) { 5233 zio_allocate_dispatch(zio->io_metaslab_class, 5234 zio->io_allocator); 5235 } 5236 } 5237 } 5238 5239 mutex_enter(&zio->io_lock); 5240 zio->io_state[ZIO_WAIT_READY] = 1; 5241 pio = zio_walk_parents(zio, &zl); 5242 mutex_exit(&zio->io_lock); 5243 5244 /* 5245 * As we notify zio's parents, new parents could be added. 5246 * New parents go to the head of zio's io_parent_list, however, 5247 * so we will (correctly) not notify them. The remainder of zio's 5248 * io_parent_list, from 'pio_next' onward, cannot change because 5249 * all parents must wait for us to be done before they can be done. 5250 */ 5251 for (; pio != NULL; pio = pio_next) { 5252 pio_next = zio_walk_parents(zio, &zl); 5253 zio_notify_parent(pio, zio, ZIO_WAIT_READY, NULL); 5254 } 5255 5256 if (zio->io_flags & ZIO_FLAG_NODATA) { 5257 if (bp != NULL && BP_IS_GANG(bp)) { 5258 zio->io_flags &= ~ZIO_FLAG_NODATA; 5259 } else { 5260 ASSERT((uintptr_t)zio->io_abd < SPA_MAXBLOCKSIZE); 5261 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES; 5262 } 5263 } 5264 5265 if (zio_injection_enabled && 5266 zio->io_spa->spa_syncing_txg == zio->io_txg) 5267 zio_handle_ignored_writes(zio); 5268 5269 return (zio); 5270 } 5271 5272 /* 5273 * Update the allocation throttle accounting. 5274 */ 5275 static void 5276 zio_dva_throttle_done(zio_t *zio) 5277 { 5278 zio_t *pio = zio_unique_parent(zio); 5279 vdev_t *vd = zio->io_vd; 5280 int flags = METASLAB_ASYNC_ALLOC; 5281 const void *tag = pio; 5282 5283 ASSERT3P(zio->io_bp, !=, NULL); 5284 ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE); 5285 ASSERT3U(zio->io_priority, ==, ZIO_PRIORITY_ASYNC_WRITE); 5286 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV); 5287 ASSERT(vd != NULL); 5288 ASSERT3P(vd, ==, vd->vdev_top); 5289 ASSERT(zio_injection_enabled || !(zio->io_flags & ZIO_FLAG_IO_RETRY)); 5290 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REPAIR)); 5291 ASSERT(zio->io_flags & ZIO_FLAG_IO_ALLOCATING); 5292 5293 /* 5294 * Parents of gang children can have two flavors -- ones that allocated 5295 * the gang header (will have ZIO_FLAG_IO_REWRITE set) and ones that 5296 * allocated the constituent blocks. The first use their parent as tag. 5297 */ 5298 if (pio->io_child_type == ZIO_CHILD_GANG && 5299 (pio->io_flags & ZIO_FLAG_IO_REWRITE)) 5300 tag = zio_unique_parent(pio); 5301 5302 ASSERT(IO_IS_ALLOCATING(pio) || (pio->io_child_type == ZIO_CHILD_GANG && 5303 (pio->io_flags & ZIO_FLAG_IO_REWRITE))); 5304 ASSERT(ZIO_HAS_ALLOCATOR(pio)); 5305 ASSERT3P(zio, !=, zio->io_logical); 5306 ASSERT(zio->io_logical != NULL); 5307 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REPAIR)); 5308 ASSERT0(zio->io_flags & ZIO_FLAG_NOPWRITE); 5309 ASSERT(zio->io_metaslab_class != NULL); 5310 ASSERT(zio->io_metaslab_class->mc_alloc_throttle_enabled); 5311 5312 metaslab_group_alloc_decrement(zio->io_spa, vd->vdev_id, 5313 pio->io_allocator, flags, pio->io_size, tag); 5314 5315 if (metaslab_class_throttle_unreserve(zio->io_metaslab_class, 1, pio)) { 5316 zio_allocate_dispatch(zio->io_metaslab_class, 5317 pio->io_allocator); 5318 } 5319 } 5320 5321 static zio_t * 5322 zio_done(zio_t *zio) 5323 { 5324 /* 5325 * Always attempt to keep stack usage minimal here since 5326 * we can be called recursively up to 19 levels deep. 5327 */ 5328 const uint64_t psize = zio->io_size; 5329 zio_t *pio, *pio_next; 5330 zio_link_t *zl = NULL; 5331 5332 /* 5333 * If our children haven't all completed, 5334 * wait for them and then repeat this pipeline stage. 5335 */ 5336 if (zio_wait_for_children(zio, ZIO_CHILD_ALL_BITS, ZIO_WAIT_DONE)) { 5337 return (NULL); 5338 } 5339 5340 /* 5341 * If the allocation throttle is enabled, then update the accounting. 5342 * We only track child I/Os that are part of an allocating async 5343 * write. We must do this since the allocation is performed 5344 * by the logical I/O but the actual write is done by child I/Os. 5345 */ 5346 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING && 5347 zio->io_child_type == ZIO_CHILD_VDEV) 5348 zio_dva_throttle_done(zio); 5349 5350 for (int c = 0; c < ZIO_CHILD_TYPES; c++) 5351 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 5352 ASSERT(zio->io_children[c][w] == 0); 5353 5354 if (zio->io_bp != NULL && !BP_IS_EMBEDDED(zio->io_bp)) { 5355 ASSERT(zio->io_bp->blk_pad[0] == 0); 5356 ASSERT(zio->io_bp->blk_pad[1] == 0); 5357 ASSERT(memcmp(zio->io_bp, &zio->io_bp_copy, 5358 sizeof (blkptr_t)) == 0 || 5359 (zio->io_bp == zio_unique_parent(zio)->io_bp)); 5360 if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(zio->io_bp) && 5361 zio->io_bp_override == NULL && 5362 !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) { 5363 ASSERT3U(zio->io_prop.zp_copies, <=, 5364 BP_GET_NDVAS(zio->io_bp)); 5365 ASSERT(BP_COUNT_GANG(zio->io_bp) == 0 || 5366 (BP_COUNT_GANG(zio->io_bp) == 5367 BP_GET_NDVAS(zio->io_bp))); 5368 } 5369 if (zio->io_flags & ZIO_FLAG_NOPWRITE) 5370 VERIFY(BP_EQUAL(zio->io_bp, &zio->io_bp_orig)); 5371 } 5372 5373 /* 5374 * If there were child vdev/gang/ddt errors, they apply to us now. 5375 */ 5376 zio_inherit_child_errors(zio, ZIO_CHILD_VDEV); 5377 zio_inherit_child_errors(zio, ZIO_CHILD_GANG); 5378 zio_inherit_child_errors(zio, ZIO_CHILD_DDT); 5379 5380 /* 5381 * If the I/O on the transformed data was successful, generate any 5382 * checksum reports now while we still have the transformed data. 5383 */ 5384 if (zio->io_error == 0) { 5385 while (zio->io_cksum_report != NULL) { 5386 zio_cksum_report_t *zcr = zio->io_cksum_report; 5387 uint64_t align = zcr->zcr_align; 5388 uint64_t asize = P2ROUNDUP(psize, align); 5389 abd_t *adata = zio->io_abd; 5390 5391 if (adata != NULL && asize != psize) { 5392 adata = abd_alloc(asize, B_TRUE); 5393 abd_copy(adata, zio->io_abd, psize); 5394 abd_zero_off(adata, psize, asize - psize); 5395 } 5396 5397 zio->io_cksum_report = zcr->zcr_next; 5398 zcr->zcr_next = NULL; 5399 zcr->zcr_finish(zcr, adata); 5400 zfs_ereport_free_checksum(zcr); 5401 5402 if (adata != NULL && asize != psize) 5403 abd_free(adata); 5404 } 5405 } 5406 5407 zio_pop_transforms(zio); /* note: may set zio->io_error */ 5408 5409 vdev_stat_update(zio, psize); 5410 5411 /* 5412 * If this I/O is attached to a particular vdev is slow, exceeding 5413 * 30 seconds to complete, post an error described the I/O delay. 5414 * We ignore these errors if the device is currently unavailable. 5415 */ 5416 if (zio->io_delay >= MSEC2NSEC(zio_slow_io_ms)) { 5417 if (zio->io_vd != NULL && !vdev_is_dead(zio->io_vd)) { 5418 /* 5419 * We want to only increment our slow IO counters if 5420 * the IO is valid (i.e. not if the drive is removed). 5421 * 5422 * zfs_ereport_post() will also do these checks, but 5423 * it can also ratelimit and have other failures, so we 5424 * need to increment the slow_io counters independent 5425 * of it. 5426 */ 5427 if (zfs_ereport_is_valid(FM_EREPORT_ZFS_DELAY, 5428 zio->io_spa, zio->io_vd, zio)) { 5429 mutex_enter(&zio->io_vd->vdev_stat_lock); 5430 zio->io_vd->vdev_stat.vs_slow_ios++; 5431 mutex_exit(&zio->io_vd->vdev_stat_lock); 5432 5433 (void) zfs_ereport_post(FM_EREPORT_ZFS_DELAY, 5434 zio->io_spa, zio->io_vd, &zio->io_bookmark, 5435 zio, 0); 5436 } 5437 } 5438 } 5439 5440 if (zio->io_error) { 5441 /* 5442 * If this I/O is attached to a particular vdev, 5443 * generate an error message describing the I/O failure 5444 * at the block level. We ignore these errors if the 5445 * device is currently unavailable. 5446 */ 5447 if (zio->io_error != ECKSUM && zio->io_vd != NULL && 5448 !vdev_is_dead(zio->io_vd) && 5449 !(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR)) { 5450 int ret = zfs_ereport_post(FM_EREPORT_ZFS_IO, 5451 zio->io_spa, zio->io_vd, &zio->io_bookmark, zio, 0); 5452 if (ret != EALREADY) { 5453 mutex_enter(&zio->io_vd->vdev_stat_lock); 5454 if (zio->io_type == ZIO_TYPE_READ) 5455 zio->io_vd->vdev_stat.vs_read_errors++; 5456 else if (zio->io_type == ZIO_TYPE_WRITE) 5457 zio->io_vd->vdev_stat.vs_write_errors++; 5458 mutex_exit(&zio->io_vd->vdev_stat_lock); 5459 } 5460 } 5461 5462 if ((zio->io_error == EIO || !(zio->io_flags & 5463 (ZIO_FLAG_SPECULATIVE | ZIO_FLAG_DONT_PROPAGATE))) && 5464 !(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR) && 5465 zio == zio->io_logical) { 5466 /* 5467 * For logical I/O requests, tell the SPA to log the 5468 * error and generate a logical data ereport. 5469 */ 5470 spa_log_error(zio->io_spa, &zio->io_bookmark, 5471 BP_GET_LOGICAL_BIRTH(zio->io_bp)); 5472 (void) zfs_ereport_post(FM_EREPORT_ZFS_DATA, 5473 zio->io_spa, NULL, &zio->io_bookmark, zio, 0); 5474 } 5475 } 5476 5477 if (zio->io_error && zio == zio->io_logical) { 5478 5479 /* 5480 * A DDT child tried to create a mixed gang/non-gang BP. We're 5481 * going to have to just retry as a non-dedup IO. 5482 */ 5483 if (zio->io_error == EAGAIN && IO_IS_ALLOCATING(zio) && 5484 zio->io_prop.zp_dedup) { 5485 zio->io_reexecute |= ZIO_REEXECUTE_NOW; 5486 zio->io_prop.zp_dedup = B_FALSE; 5487 } 5488 /* 5489 * Determine whether zio should be reexecuted. This will 5490 * propagate all the way to the root via zio_notify_parent(). 5491 */ 5492 ASSERT(zio->io_vd == NULL && zio->io_bp != NULL); 5493 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 5494 5495 if (IO_IS_ALLOCATING(zio) && 5496 !(zio->io_flags & ZIO_FLAG_CANFAIL) && 5497 !(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR)) { 5498 if (zio->io_error != ENOSPC) 5499 zio->io_reexecute |= ZIO_REEXECUTE_NOW; 5500 else 5501 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 5502 } 5503 5504 if ((zio->io_type == ZIO_TYPE_READ || 5505 zio->io_type == ZIO_TYPE_FREE) && 5506 !(zio->io_flags & ZIO_FLAG_SCAN_THREAD) && 5507 zio->io_error == ENXIO && 5508 spa_load_state(zio->io_spa) == SPA_LOAD_NONE && 5509 spa_get_failmode(zio->io_spa) != ZIO_FAILURE_MODE_CONTINUE) 5510 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 5511 5512 if (!(zio->io_flags & ZIO_FLAG_CANFAIL) && !zio->io_reexecute) 5513 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 5514 5515 /* 5516 * Here is a possibly good place to attempt to do 5517 * either combinatorial reconstruction or error correction 5518 * based on checksums. It also might be a good place 5519 * to send out preliminary ereports before we suspend 5520 * processing. 5521 */ 5522 } 5523 5524 /* 5525 * If there were logical child errors, they apply to us now. 5526 * We defer this until now to avoid conflating logical child 5527 * errors with errors that happened to the zio itself when 5528 * updating vdev stats and reporting FMA events above. 5529 */ 5530 zio_inherit_child_errors(zio, ZIO_CHILD_LOGICAL); 5531 5532 if ((zio->io_error || zio->io_reexecute) && 5533 IO_IS_ALLOCATING(zio) && zio->io_gang_leader == zio && 5534 !(zio->io_flags & (ZIO_FLAG_IO_REWRITE | ZIO_FLAG_NOPWRITE))) 5535 zio_dva_unallocate(zio, zio->io_gang_tree, zio->io_bp); 5536 5537 zio_gang_tree_free(&zio->io_gang_tree); 5538 5539 /* 5540 * Godfather I/Os should never suspend. 5541 */ 5542 if ((zio->io_flags & ZIO_FLAG_GODFATHER) && 5543 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) 5544 zio->io_reexecute &= ~ZIO_REEXECUTE_SUSPEND; 5545 5546 if (zio->io_reexecute) { 5547 /* 5548 * A Direct I/O operation that has a checksum verify error 5549 * should not attempt to reexecute. Instead, the error should 5550 * just be propagated back. 5551 */ 5552 ASSERT(!(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR)); 5553 5554 /* 5555 * This is a logical I/O that wants to reexecute. 5556 * 5557 * Reexecute is top-down. When an i/o fails, if it's not 5558 * the root, it simply notifies its parent and sticks around. 5559 * The parent, seeing that it still has children in zio_done(), 5560 * does the same. This percolates all the way up to the root. 5561 * The root i/o will reexecute or suspend the entire tree. 5562 * 5563 * This approach ensures that zio_reexecute() honors 5564 * all the original i/o dependency relationships, e.g. 5565 * parents not executing until children are ready. 5566 */ 5567 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 5568 5569 zio->io_gang_leader = NULL; 5570 5571 mutex_enter(&zio->io_lock); 5572 zio->io_state[ZIO_WAIT_DONE] = 1; 5573 mutex_exit(&zio->io_lock); 5574 5575 /* 5576 * "The Godfather" I/O monitors its children but is 5577 * not a true parent to them. It will track them through 5578 * the pipeline but severs its ties whenever they get into 5579 * trouble (e.g. suspended). This allows "The Godfather" 5580 * I/O to return status without blocking. 5581 */ 5582 zl = NULL; 5583 for (pio = zio_walk_parents(zio, &zl); pio != NULL; 5584 pio = pio_next) { 5585 zio_link_t *remove_zl = zl; 5586 pio_next = zio_walk_parents(zio, &zl); 5587 5588 if ((pio->io_flags & ZIO_FLAG_GODFATHER) && 5589 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) { 5590 zio_remove_child(pio, zio, remove_zl); 5591 /* 5592 * This is a rare code path, so we don't 5593 * bother with "next_to_execute". 5594 */ 5595 zio_notify_parent(pio, zio, ZIO_WAIT_DONE, 5596 NULL); 5597 } 5598 } 5599 5600 if ((pio = zio_unique_parent(zio)) != NULL) { 5601 /* 5602 * We're not a root i/o, so there's nothing to do 5603 * but notify our parent. Don't propagate errors 5604 * upward since we haven't permanently failed yet. 5605 */ 5606 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER)); 5607 zio->io_flags |= ZIO_FLAG_DONT_PROPAGATE; 5608 /* 5609 * This is a rare code path, so we don't bother with 5610 * "next_to_execute". 5611 */ 5612 zio_notify_parent(pio, zio, ZIO_WAIT_DONE, NULL); 5613 } else if (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND) { 5614 /* 5615 * We'd fail again if we reexecuted now, so suspend 5616 * until conditions improve (e.g. device comes online). 5617 */ 5618 zio_suspend(zio->io_spa, zio, ZIO_SUSPEND_IOERR); 5619 } else { 5620 /* 5621 * Reexecution is potentially a huge amount of work. 5622 * Hand it off to the otherwise-unused claim taskq. 5623 */ 5624 spa_taskq_dispatch(zio->io_spa, 5625 ZIO_TYPE_CLAIM, ZIO_TASKQ_ISSUE, 5626 zio_reexecute, zio, B_FALSE); 5627 } 5628 return (NULL); 5629 } 5630 5631 ASSERT(list_is_empty(&zio->io_child_list)); 5632 ASSERT(zio->io_reexecute == 0); 5633 ASSERT(zio->io_error == 0 || (zio->io_flags & ZIO_FLAG_CANFAIL)); 5634 5635 /* 5636 * Report any checksum errors, since the I/O is complete. 5637 */ 5638 while (zio->io_cksum_report != NULL) { 5639 zio_cksum_report_t *zcr = zio->io_cksum_report; 5640 zio->io_cksum_report = zcr->zcr_next; 5641 zcr->zcr_next = NULL; 5642 zcr->zcr_finish(zcr, NULL); 5643 zfs_ereport_free_checksum(zcr); 5644 } 5645 5646 /* 5647 * It is the responsibility of the done callback to ensure that this 5648 * particular zio is no longer discoverable for adoption, and as 5649 * such, cannot acquire any new parents. 5650 */ 5651 if (zio->io_done) 5652 zio->io_done(zio); 5653 5654 mutex_enter(&zio->io_lock); 5655 zio->io_state[ZIO_WAIT_DONE] = 1; 5656 mutex_exit(&zio->io_lock); 5657 5658 /* 5659 * We are done executing this zio. We may want to execute a parent 5660 * next. See the comment in zio_notify_parent(). 5661 */ 5662 zio_t *next_to_execute = NULL; 5663 zl = NULL; 5664 for (pio = zio_walk_parents(zio, &zl); pio != NULL; pio = pio_next) { 5665 zio_link_t *remove_zl = zl; 5666 pio_next = zio_walk_parents(zio, &zl); 5667 zio_remove_child(pio, zio, remove_zl); 5668 zio_notify_parent(pio, zio, ZIO_WAIT_DONE, &next_to_execute); 5669 } 5670 5671 if (zio->io_waiter != NULL) { 5672 mutex_enter(&zio->io_lock); 5673 zio->io_executor = NULL; 5674 cv_broadcast(&zio->io_cv); 5675 mutex_exit(&zio->io_lock); 5676 } else { 5677 zio_destroy(zio); 5678 } 5679 5680 return (next_to_execute); 5681 } 5682 5683 /* 5684 * ========================================================================== 5685 * I/O pipeline definition 5686 * ========================================================================== 5687 */ 5688 static zio_pipe_stage_t *zio_pipeline[] = { 5689 NULL, 5690 zio_read_bp_init, 5691 zio_write_bp_init, 5692 zio_free_bp_init, 5693 zio_issue_async, 5694 zio_write_compress, 5695 zio_encrypt, 5696 zio_checksum_generate, 5697 zio_nop_write, 5698 zio_brt_free, 5699 zio_ddt_read_start, 5700 zio_ddt_read_done, 5701 zio_ddt_write, 5702 zio_ddt_free, 5703 zio_gang_assemble, 5704 zio_gang_issue, 5705 zio_dva_throttle, 5706 zio_dva_allocate, 5707 zio_dva_free, 5708 zio_dva_claim, 5709 zio_ready, 5710 zio_vdev_io_start, 5711 zio_vdev_io_done, 5712 zio_vdev_io_assess, 5713 zio_checksum_verify, 5714 zio_dio_checksum_verify, 5715 zio_done 5716 }; 5717 5718 5719 5720 5721 /* 5722 * Compare two zbookmark_phys_t's to see which we would reach first in a 5723 * pre-order traversal of the object tree. 5724 * 5725 * This is simple in every case aside from the meta-dnode object. For all other 5726 * objects, we traverse them in order (object 1 before object 2, and so on). 5727 * However, all of these objects are traversed while traversing object 0, since 5728 * the data it points to is the list of objects. Thus, we need to convert to a 5729 * canonical representation so we can compare meta-dnode bookmarks to 5730 * non-meta-dnode bookmarks. 5731 * 5732 * We do this by calculating "equivalents" for each field of the zbookmark. 5733 * zbookmarks outside of the meta-dnode use their own object and level, and 5734 * calculate the level 0 equivalent (the first L0 blkid that is contained in the 5735 * blocks this bookmark refers to) by multiplying their blkid by their span 5736 * (the number of L0 blocks contained within one block at their level). 5737 * zbookmarks inside the meta-dnode calculate their object equivalent 5738 * (which is L0equiv * dnodes per data block), use 0 for their L0equiv, and use 5739 * level + 1<<31 (any value larger than a level could ever be) for their level. 5740 * This causes them to always compare before a bookmark in their object 5741 * equivalent, compare appropriately to bookmarks in other objects, and to 5742 * compare appropriately to other bookmarks in the meta-dnode. 5743 */ 5744 int 5745 zbookmark_compare(uint16_t dbss1, uint8_t ibs1, uint16_t dbss2, uint8_t ibs2, 5746 const zbookmark_phys_t *zb1, const zbookmark_phys_t *zb2) 5747 { 5748 /* 5749 * These variables represent the "equivalent" values for the zbookmark, 5750 * after converting zbookmarks inside the meta dnode to their 5751 * normal-object equivalents. 5752 */ 5753 uint64_t zb1obj, zb2obj; 5754 uint64_t zb1L0, zb2L0; 5755 uint64_t zb1level, zb2level; 5756 5757 if (zb1->zb_object == zb2->zb_object && 5758 zb1->zb_level == zb2->zb_level && 5759 zb1->zb_blkid == zb2->zb_blkid) 5760 return (0); 5761 5762 IMPLY(zb1->zb_level > 0, ibs1 >= SPA_MINBLOCKSHIFT); 5763 IMPLY(zb2->zb_level > 0, ibs2 >= SPA_MINBLOCKSHIFT); 5764 5765 /* 5766 * BP_SPANB calculates the span in blocks. 5767 */ 5768 zb1L0 = (zb1->zb_blkid) * BP_SPANB(ibs1, zb1->zb_level); 5769 zb2L0 = (zb2->zb_blkid) * BP_SPANB(ibs2, zb2->zb_level); 5770 5771 if (zb1->zb_object == DMU_META_DNODE_OBJECT) { 5772 zb1obj = zb1L0 * (dbss1 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT)); 5773 zb1L0 = 0; 5774 zb1level = zb1->zb_level + COMPARE_META_LEVEL; 5775 } else { 5776 zb1obj = zb1->zb_object; 5777 zb1level = zb1->zb_level; 5778 } 5779 5780 if (zb2->zb_object == DMU_META_DNODE_OBJECT) { 5781 zb2obj = zb2L0 * (dbss2 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT)); 5782 zb2L0 = 0; 5783 zb2level = zb2->zb_level + COMPARE_META_LEVEL; 5784 } else { 5785 zb2obj = zb2->zb_object; 5786 zb2level = zb2->zb_level; 5787 } 5788 5789 /* Now that we have a canonical representation, do the comparison. */ 5790 if (zb1obj != zb2obj) 5791 return (zb1obj < zb2obj ? -1 : 1); 5792 else if (zb1L0 != zb2L0) 5793 return (zb1L0 < zb2L0 ? -1 : 1); 5794 else if (zb1level != zb2level) 5795 return (zb1level > zb2level ? -1 : 1); 5796 /* 5797 * This can (theoretically) happen if the bookmarks have the same object 5798 * and level, but different blkids, if the block sizes are not the same. 5799 * There is presently no way to change the indirect block sizes 5800 */ 5801 return (0); 5802 } 5803 5804 /* 5805 * This function checks the following: given that last_block is the place that 5806 * our traversal stopped last time, does that guarantee that we've visited 5807 * every node under subtree_root? Therefore, we can't just use the raw output 5808 * of zbookmark_compare. We have to pass in a modified version of 5809 * subtree_root; by incrementing the block id, and then checking whether 5810 * last_block is before or equal to that, we can tell whether or not having 5811 * visited last_block implies that all of subtree_root's children have been 5812 * visited. 5813 */ 5814 boolean_t 5815 zbookmark_subtree_completed(const dnode_phys_t *dnp, 5816 const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block) 5817 { 5818 zbookmark_phys_t mod_zb = *subtree_root; 5819 mod_zb.zb_blkid++; 5820 ASSERT0(last_block->zb_level); 5821 5822 /* The objset_phys_t isn't before anything. */ 5823 if (dnp == NULL) 5824 return (B_FALSE); 5825 5826 /* 5827 * We pass in 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT) for the 5828 * data block size in sectors, because that variable is only used if 5829 * the bookmark refers to a block in the meta-dnode. Since we don't 5830 * know without examining it what object it refers to, and there's no 5831 * harm in passing in this value in other cases, we always pass it in. 5832 * 5833 * We pass in 0 for the indirect block size shift because zb2 must be 5834 * level 0. The indirect block size is only used to calculate the span 5835 * of the bookmark, but since the bookmark must be level 0, the span is 5836 * always 1, so the math works out. 5837 * 5838 * If you make changes to how the zbookmark_compare code works, be sure 5839 * to make sure that this code still works afterwards. 5840 */ 5841 return (zbookmark_compare(dnp->dn_datablkszsec, dnp->dn_indblkshift, 5842 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT), 0, &mod_zb, 5843 last_block) <= 0); 5844 } 5845 5846 /* 5847 * This function is similar to zbookmark_subtree_completed(), but returns true 5848 * if subtree_root is equal or ahead of last_block, i.e. still to be done. 5849 */ 5850 boolean_t 5851 zbookmark_subtree_tbd(const dnode_phys_t *dnp, 5852 const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block) 5853 { 5854 ASSERT0(last_block->zb_level); 5855 if (dnp == NULL) 5856 return (B_FALSE); 5857 return (zbookmark_compare(dnp->dn_datablkszsec, dnp->dn_indblkshift, 5858 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT), 0, subtree_root, 5859 last_block) >= 0); 5860 } 5861 5862 EXPORT_SYMBOL(zio_type_name); 5863 EXPORT_SYMBOL(zio_buf_alloc); 5864 EXPORT_SYMBOL(zio_data_buf_alloc); 5865 EXPORT_SYMBOL(zio_buf_free); 5866 EXPORT_SYMBOL(zio_data_buf_free); 5867 5868 ZFS_MODULE_PARAM(zfs_zio, zio_, slow_io_ms, INT, ZMOD_RW, 5869 "Max I/O completion time (milliseconds) before marking it as slow"); 5870 5871 ZFS_MODULE_PARAM(zfs_zio, zio_, requeue_io_start_cut_in_line, INT, ZMOD_RW, 5872 "Prioritize requeued I/O"); 5873 5874 ZFS_MODULE_PARAM(zfs, zfs_, sync_pass_deferred_free, UINT, ZMOD_RW, 5875 "Defer frees starting in this pass"); 5876 5877 ZFS_MODULE_PARAM(zfs, zfs_, sync_pass_dont_compress, UINT, ZMOD_RW, 5878 "Don't compress starting in this pass"); 5879 5880 ZFS_MODULE_PARAM(zfs, zfs_, sync_pass_rewrite, UINT, ZMOD_RW, 5881 "Rewrite new bps starting in this pass"); 5882 5883 ZFS_MODULE_PARAM(zfs_zio, zio_, dva_throttle_enabled, INT, ZMOD_RW, 5884 "Throttle block allocations in the ZIO pipeline"); 5885 5886 ZFS_MODULE_PARAM(zfs_zio, zio_, deadman_log_all, INT, ZMOD_RW, 5887 "Log all slow ZIOs, not just those with vdevs"); 5888