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