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 if (zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR) { 808 ASSERT3U(*errorp, ==, EIO); 809 ASSERT3U(pio->io_child_type, ==, ZIO_CHILD_LOGICAL); 810 pio->io_flags |= ZIO_FLAG_DIO_CHKSUM_ERR; 811 } 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 } else if (type == ZIO_TYPE_WRITE && 1577 pio->io_prop.zp_direct_write == B_TRUE) { 1578 /* 1579 * By default we only will verify checksums for Direct I/O 1580 * writes for Linux. FreeBSD is able to place user pages under 1581 * write protection before issuing them to the ZIO pipeline. 1582 * 1583 * Checksum validation errors will only be reported through 1584 * the top-level VDEV, which is set by this child ZIO. 1585 */ 1586 ASSERT3P(bp, !=, NULL); 1587 ASSERT3U(pio->io_child_type, ==, ZIO_CHILD_LOGICAL); 1588 pipeline |= ZIO_STAGE_DIO_CHECKSUM_VERIFY; 1589 } 1590 1591 if (vd->vdev_ops->vdev_op_leaf) { 1592 ASSERT0(vd->vdev_children); 1593 offset += VDEV_LABEL_START_SIZE; 1594 } 1595 1596 flags |= ZIO_VDEV_CHILD_FLAGS(pio); 1597 1598 /* 1599 * If we've decided to do a repair, the write is not speculative -- 1600 * even if the original read was. 1601 */ 1602 if (flags & ZIO_FLAG_IO_REPAIR) 1603 flags &= ~ZIO_FLAG_SPECULATIVE; 1604 1605 /* 1606 * If we're creating a child I/O that is not associated with a 1607 * top-level vdev, then the child zio is not an allocating I/O. 1608 * If this is a retried I/O then we ignore it since we will 1609 * have already processed the original allocating I/O. 1610 */ 1611 if (flags & ZIO_FLAG_IO_ALLOCATING && 1612 (vd != vd->vdev_top || (flags & ZIO_FLAG_IO_RETRY))) { 1613 ASSERT(pio->io_metaslab_class != NULL); 1614 ASSERT(pio->io_metaslab_class->mc_alloc_throttle_enabled); 1615 ASSERT(type == ZIO_TYPE_WRITE); 1616 ASSERT(priority == ZIO_PRIORITY_ASYNC_WRITE); 1617 ASSERT(!(flags & ZIO_FLAG_IO_REPAIR)); 1618 ASSERT(!(pio->io_flags & ZIO_FLAG_IO_REWRITE) || 1619 pio->io_child_type == ZIO_CHILD_GANG); 1620 1621 flags &= ~ZIO_FLAG_IO_ALLOCATING; 1622 } 1623 1624 zio = zio_create(pio, pio->io_spa, pio->io_txg, bp, data, size, size, 1625 done, private, type, priority, flags, vd, offset, &pio->io_bookmark, 1626 ZIO_STAGE_VDEV_IO_START >> 1, pipeline); 1627 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV); 1628 1629 return (zio); 1630 } 1631 1632 zio_t * 1633 zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, abd_t *data, uint64_t size, 1634 zio_type_t type, zio_priority_t priority, zio_flag_t flags, 1635 zio_done_func_t *done, void *private) 1636 { 1637 zio_t *zio; 1638 1639 ASSERT(vd->vdev_ops->vdev_op_leaf); 1640 1641 zio = zio_create(NULL, vd->vdev_spa, 0, NULL, 1642 data, size, size, done, private, type, priority, 1643 flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY | ZIO_FLAG_DELEGATED, 1644 vd, offset, NULL, 1645 ZIO_STAGE_VDEV_IO_START >> 1, ZIO_VDEV_CHILD_PIPELINE); 1646 1647 return (zio); 1648 } 1649 1650 1651 /* 1652 * Send a flush command to the given vdev. Unlike most zio creation functions, 1653 * the flush zios are issued immediately. You can wait on pio to pause until 1654 * the flushes complete. 1655 */ 1656 void 1657 zio_flush(zio_t *pio, vdev_t *vd) 1658 { 1659 const zio_flag_t flags = ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | 1660 ZIO_FLAG_DONT_RETRY; 1661 1662 if (vd->vdev_nowritecache) 1663 return; 1664 1665 if (vd->vdev_children == 0) { 1666 zio_nowait(zio_create(pio, vd->vdev_spa, 0, NULL, NULL, 0, 0, 1667 NULL, NULL, ZIO_TYPE_FLUSH, ZIO_PRIORITY_NOW, flags, vd, 0, 1668 NULL, ZIO_STAGE_OPEN, ZIO_FLUSH_PIPELINE)); 1669 } else { 1670 for (uint64_t c = 0; c < vd->vdev_children; c++) 1671 zio_flush(pio, vd->vdev_child[c]); 1672 } 1673 } 1674 1675 void 1676 zio_shrink(zio_t *zio, uint64_t size) 1677 { 1678 ASSERT3P(zio->io_executor, ==, NULL); 1679 ASSERT3U(zio->io_orig_size, ==, zio->io_size); 1680 ASSERT3U(size, <=, zio->io_size); 1681 1682 /* 1683 * We don't shrink for raidz because of problems with the 1684 * reconstruction when reading back less than the block size. 1685 * Note, BP_IS_RAIDZ() assumes no compression. 1686 */ 1687 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); 1688 if (!BP_IS_RAIDZ(zio->io_bp)) { 1689 /* we are not doing a raw write */ 1690 ASSERT3U(zio->io_size, ==, zio->io_lsize); 1691 zio->io_orig_size = zio->io_size = zio->io_lsize = size; 1692 } 1693 } 1694 1695 /* 1696 * Round provided allocation size up to a value that can be allocated 1697 * by at least some vdev(s) in the pool with minimum or no additional 1698 * padding and without extra space usage on others 1699 */ 1700 static uint64_t 1701 zio_roundup_alloc_size(spa_t *spa, uint64_t size) 1702 { 1703 if (size > spa->spa_min_alloc) 1704 return (roundup(size, spa->spa_gcd_alloc)); 1705 return (spa->spa_min_alloc); 1706 } 1707 1708 size_t 1709 zio_get_compression_max_size(enum zio_compress compress, uint64_t gcd_alloc, 1710 uint64_t min_alloc, size_t s_len) 1711 { 1712 size_t d_len; 1713 1714 /* minimum 12.5% must be saved (legacy value, may be changed later) */ 1715 d_len = s_len - (s_len >> 3); 1716 1717 /* ZLE can't use exactly d_len bytes, it needs more, so ignore it */ 1718 if (compress == ZIO_COMPRESS_ZLE) 1719 return (d_len); 1720 1721 d_len = d_len - d_len % gcd_alloc; 1722 1723 if (d_len < min_alloc) 1724 return (BPE_PAYLOAD_SIZE); 1725 return (d_len); 1726 } 1727 1728 /* 1729 * ========================================================================== 1730 * Prepare to read and write logical blocks 1731 * ========================================================================== 1732 */ 1733 1734 static zio_t * 1735 zio_read_bp_init(zio_t *zio) 1736 { 1737 blkptr_t *bp = zio->io_bp; 1738 uint64_t psize = 1739 BP_IS_EMBEDDED(bp) ? BPE_GET_PSIZE(bp) : BP_GET_PSIZE(bp); 1740 1741 ASSERT3P(zio->io_bp, ==, &zio->io_bp_copy); 1742 1743 if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF && 1744 zio->io_child_type == ZIO_CHILD_LOGICAL && 1745 !(zio->io_flags & ZIO_FLAG_RAW_COMPRESS)) { 1746 zio_push_transform(zio, abd_alloc_sametype(zio->io_abd, psize), 1747 psize, psize, zio_decompress); 1748 } 1749 1750 if (((BP_IS_PROTECTED(bp) && !(zio->io_flags & ZIO_FLAG_RAW_ENCRYPT)) || 1751 BP_HAS_INDIRECT_MAC_CKSUM(bp)) && 1752 zio->io_child_type == ZIO_CHILD_LOGICAL) { 1753 zio_push_transform(zio, abd_alloc_sametype(zio->io_abd, psize), 1754 psize, psize, zio_decrypt); 1755 } 1756 1757 if (BP_IS_EMBEDDED(bp) && BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA) { 1758 int psize = BPE_GET_PSIZE(bp); 1759 void *data = abd_borrow_buf(zio->io_abd, psize); 1760 1761 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1762 decode_embedded_bp_compressed(bp, data); 1763 abd_return_buf_copy(zio->io_abd, data, psize); 1764 } else { 1765 ASSERT(!BP_IS_EMBEDDED(bp)); 1766 } 1767 1768 if (BP_GET_DEDUP(bp) && zio->io_child_type == ZIO_CHILD_LOGICAL) 1769 zio->io_pipeline = ZIO_DDT_READ_PIPELINE; 1770 1771 return (zio); 1772 } 1773 1774 static zio_t * 1775 zio_write_bp_init(zio_t *zio) 1776 { 1777 if (!IO_IS_ALLOCATING(zio)) 1778 return (zio); 1779 1780 ASSERT(zio->io_child_type != ZIO_CHILD_DDT); 1781 1782 if (zio->io_bp_override) { 1783 blkptr_t *bp = zio->io_bp; 1784 zio_prop_t *zp = &zio->io_prop; 1785 1786 ASSERT(BP_GET_LOGICAL_BIRTH(bp) != zio->io_txg); 1787 1788 *bp = *zio->io_bp_override; 1789 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1790 1791 if (zp->zp_brtwrite) 1792 return (zio); 1793 1794 ASSERT(!BP_GET_DEDUP(zio->io_bp_override)); 1795 1796 if (BP_IS_EMBEDDED(bp)) 1797 return (zio); 1798 1799 /* 1800 * If we've been overridden and nopwrite is set then 1801 * set the flag accordingly to indicate that a nopwrite 1802 * has already occurred. 1803 */ 1804 if (!BP_IS_HOLE(bp) && zp->zp_nopwrite) { 1805 ASSERT(!zp->zp_dedup); 1806 ASSERT3U(BP_GET_CHECKSUM(bp), ==, zp->zp_checksum); 1807 zio->io_flags |= ZIO_FLAG_NOPWRITE; 1808 return (zio); 1809 } 1810 1811 ASSERT(!zp->zp_nopwrite); 1812 1813 if (BP_IS_HOLE(bp) || !zp->zp_dedup) 1814 return (zio); 1815 1816 ASSERT((zio_checksum_table[zp->zp_checksum].ci_flags & 1817 ZCHECKSUM_FLAG_DEDUP) || zp->zp_dedup_verify); 1818 1819 if (BP_GET_CHECKSUM(bp) == zp->zp_checksum && 1820 !zp->zp_encrypt) { 1821 BP_SET_DEDUP(bp, 1); 1822 zio->io_pipeline |= ZIO_STAGE_DDT_WRITE; 1823 return (zio); 1824 } 1825 1826 /* 1827 * We were unable to handle this as an override bp, treat 1828 * it as a regular write I/O. 1829 */ 1830 zio->io_bp_override = NULL; 1831 *bp = zio->io_bp_orig; 1832 zio->io_pipeline = zio->io_orig_pipeline; 1833 } 1834 1835 return (zio); 1836 } 1837 1838 static zio_t * 1839 zio_write_compress(zio_t *zio) 1840 { 1841 spa_t *spa = zio->io_spa; 1842 zio_prop_t *zp = &zio->io_prop; 1843 enum zio_compress compress = zp->zp_compress; 1844 blkptr_t *bp = zio->io_bp; 1845 uint64_t lsize = zio->io_lsize; 1846 uint64_t psize = zio->io_size; 1847 uint32_t pass = 1; 1848 1849 /* 1850 * If our children haven't all reached the ready stage, 1851 * wait for them and then repeat this pipeline stage. 1852 */ 1853 if (zio_wait_for_children(zio, ZIO_CHILD_LOGICAL_BIT | 1854 ZIO_CHILD_GANG_BIT, ZIO_WAIT_READY)) { 1855 return (NULL); 1856 } 1857 1858 if (!IO_IS_ALLOCATING(zio)) 1859 return (zio); 1860 1861 if (zio->io_children_ready != NULL) { 1862 /* 1863 * Now that all our children are ready, run the callback 1864 * associated with this zio in case it wants to modify the 1865 * data to be written. 1866 */ 1867 ASSERT3U(zp->zp_level, >, 0); 1868 zio->io_children_ready(zio); 1869 } 1870 1871 ASSERT(zio->io_child_type != ZIO_CHILD_DDT); 1872 ASSERT(zio->io_bp_override == NULL); 1873 1874 if (!BP_IS_HOLE(bp) && BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg) { 1875 /* 1876 * We're rewriting an existing block, which means we're 1877 * working on behalf of spa_sync(). For spa_sync() to 1878 * converge, it must eventually be the case that we don't 1879 * have to allocate new blocks. But compression changes 1880 * the blocksize, which forces a reallocate, and makes 1881 * convergence take longer. Therefore, after the first 1882 * few passes, stop compressing to ensure convergence. 1883 */ 1884 pass = spa_sync_pass(spa); 1885 1886 ASSERT(zio->io_txg == spa_syncing_txg(spa)); 1887 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 1888 ASSERT(!BP_GET_DEDUP(bp)); 1889 1890 if (pass >= zfs_sync_pass_dont_compress) 1891 compress = ZIO_COMPRESS_OFF; 1892 1893 /* Make sure someone doesn't change their mind on overwrites */ 1894 ASSERT(BP_IS_EMBEDDED(bp) || BP_IS_GANG(bp) || 1895 MIN(zp->zp_copies, spa_max_replication(spa)) 1896 == BP_GET_NDVAS(bp)); 1897 } 1898 1899 /* If it's a compressed write that is not raw, compress the buffer. */ 1900 if (compress != ZIO_COMPRESS_OFF && 1901 !(zio->io_flags & ZIO_FLAG_RAW_COMPRESS)) { 1902 abd_t *cabd = NULL; 1903 if (abd_cmp_zero(zio->io_abd, lsize) == 0) 1904 psize = 0; 1905 else if (compress == ZIO_COMPRESS_EMPTY) 1906 psize = lsize; 1907 else 1908 psize = zio_compress_data(compress, zio->io_abd, &cabd, 1909 lsize, 1910 zio_get_compression_max_size(compress, 1911 spa->spa_gcd_alloc, spa->spa_min_alloc, lsize), 1912 zp->zp_complevel); 1913 if (psize == 0) { 1914 compress = ZIO_COMPRESS_OFF; 1915 } else if (psize >= lsize) { 1916 compress = ZIO_COMPRESS_OFF; 1917 if (cabd != NULL) 1918 abd_free(cabd); 1919 } else if (!zp->zp_dedup && !zp->zp_encrypt && 1920 psize <= BPE_PAYLOAD_SIZE && 1921 zp->zp_level == 0 && !DMU_OT_HAS_FILL(zp->zp_type) && 1922 spa_feature_is_enabled(spa, SPA_FEATURE_EMBEDDED_DATA)) { 1923 void *cbuf = abd_borrow_buf_copy(cabd, lsize); 1924 encode_embedded_bp_compressed(bp, 1925 cbuf, compress, lsize, psize); 1926 BPE_SET_ETYPE(bp, BP_EMBEDDED_TYPE_DATA); 1927 BP_SET_TYPE(bp, zio->io_prop.zp_type); 1928 BP_SET_LEVEL(bp, zio->io_prop.zp_level); 1929 abd_return_buf(cabd, cbuf, lsize); 1930 abd_free(cabd); 1931 BP_SET_LOGICAL_BIRTH(bp, zio->io_txg); 1932 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 1933 ASSERT(spa_feature_is_active(spa, 1934 SPA_FEATURE_EMBEDDED_DATA)); 1935 return (zio); 1936 } else { 1937 /* 1938 * Round compressed size up to the minimum allocation 1939 * size of the smallest-ashift device, and zero the 1940 * tail. This ensures that the compressed size of the 1941 * BP (and thus compressratio property) are correct, 1942 * in that we charge for the padding used to fill out 1943 * the last sector. 1944 */ 1945 size_t rounded = (size_t)zio_roundup_alloc_size(spa, 1946 psize); 1947 if (rounded >= lsize) { 1948 compress = ZIO_COMPRESS_OFF; 1949 abd_free(cabd); 1950 psize = lsize; 1951 } else { 1952 abd_zero_off(cabd, psize, rounded - psize); 1953 psize = rounded; 1954 zio_push_transform(zio, cabd, 1955 psize, lsize, NULL); 1956 } 1957 } 1958 1959 /* 1960 * We were unable to handle this as an override bp, treat 1961 * it as a regular write I/O. 1962 */ 1963 zio->io_bp_override = NULL; 1964 *bp = zio->io_bp_orig; 1965 zio->io_pipeline = zio->io_orig_pipeline; 1966 1967 } else if ((zio->io_flags & ZIO_FLAG_RAW_ENCRYPT) != 0 && 1968 zp->zp_type == DMU_OT_DNODE) { 1969 /* 1970 * The DMU actually relies on the zio layer's compression 1971 * to free metadnode blocks that have had all contained 1972 * dnodes freed. As a result, even when doing a raw 1973 * receive, we must check whether the block can be compressed 1974 * to a hole. 1975 */ 1976 if (abd_cmp_zero(zio->io_abd, lsize) == 0) { 1977 psize = 0; 1978 compress = ZIO_COMPRESS_OFF; 1979 } else { 1980 psize = lsize; 1981 } 1982 } else if (zio->io_flags & ZIO_FLAG_RAW_COMPRESS && 1983 !(zio->io_flags & ZIO_FLAG_RAW_ENCRYPT)) { 1984 /* 1985 * If we are raw receiving an encrypted dataset we should not 1986 * take this codepath because it will change the on-disk block 1987 * and decryption will fail. 1988 */ 1989 size_t rounded = MIN((size_t)zio_roundup_alloc_size(spa, psize), 1990 lsize); 1991 1992 if (rounded != psize) { 1993 abd_t *cdata = abd_alloc_linear(rounded, B_TRUE); 1994 abd_zero_off(cdata, psize, rounded - psize); 1995 abd_copy_off(cdata, zio->io_abd, 0, 0, psize); 1996 psize = rounded; 1997 zio_push_transform(zio, cdata, 1998 psize, rounded, NULL); 1999 } 2000 } else { 2001 ASSERT3U(psize, !=, 0); 2002 } 2003 2004 /* 2005 * The final pass of spa_sync() must be all rewrites, but the first 2006 * few passes offer a trade-off: allocating blocks defers convergence, 2007 * but newly allocated blocks are sequential, so they can be written 2008 * to disk faster. Therefore, we allow the first few passes of 2009 * spa_sync() to allocate new blocks, but force rewrites after that. 2010 * There should only be a handful of blocks after pass 1 in any case. 2011 */ 2012 if (!BP_IS_HOLE(bp) && BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg && 2013 BP_GET_PSIZE(bp) == psize && 2014 pass >= zfs_sync_pass_rewrite) { 2015 VERIFY3U(psize, !=, 0); 2016 enum zio_stage gang_stages = zio->io_pipeline & ZIO_GANG_STAGES; 2017 2018 zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages; 2019 zio->io_flags |= ZIO_FLAG_IO_REWRITE; 2020 } else { 2021 BP_ZERO(bp); 2022 zio->io_pipeline = ZIO_WRITE_PIPELINE; 2023 } 2024 2025 if (psize == 0) { 2026 if (BP_GET_LOGICAL_BIRTH(&zio->io_bp_orig) != 0 && 2027 spa_feature_is_active(spa, SPA_FEATURE_HOLE_BIRTH)) { 2028 BP_SET_LSIZE(bp, lsize); 2029 BP_SET_TYPE(bp, zp->zp_type); 2030 BP_SET_LEVEL(bp, zp->zp_level); 2031 BP_SET_BIRTH(bp, zio->io_txg, 0); 2032 } 2033 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 2034 } else { 2035 ASSERT(zp->zp_checksum != ZIO_CHECKSUM_GANG_HEADER); 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_PSIZE(bp, psize); 2040 BP_SET_COMPRESS(bp, compress); 2041 BP_SET_CHECKSUM(bp, zp->zp_checksum); 2042 BP_SET_DEDUP(bp, zp->zp_dedup); 2043 BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER); 2044 if (zp->zp_dedup) { 2045 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2046 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 2047 ASSERT(!zp->zp_encrypt || 2048 DMU_OT_IS_ENCRYPTED(zp->zp_type)); 2049 zio->io_pipeline = ZIO_DDT_WRITE_PIPELINE; 2050 } 2051 if (zp->zp_nopwrite) { 2052 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2053 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 2054 zio->io_pipeline |= ZIO_STAGE_NOP_WRITE; 2055 } 2056 } 2057 return (zio); 2058 } 2059 2060 static zio_t * 2061 zio_free_bp_init(zio_t *zio) 2062 { 2063 blkptr_t *bp = zio->io_bp; 2064 2065 if (zio->io_child_type == ZIO_CHILD_LOGICAL) { 2066 if (BP_GET_DEDUP(bp)) 2067 zio->io_pipeline = ZIO_DDT_FREE_PIPELINE; 2068 } 2069 2070 ASSERT3P(zio->io_bp, ==, &zio->io_bp_copy); 2071 2072 return (zio); 2073 } 2074 2075 /* 2076 * ========================================================================== 2077 * Execute the I/O pipeline 2078 * ========================================================================== 2079 */ 2080 2081 static void 2082 zio_taskq_dispatch(zio_t *zio, zio_taskq_type_t q, boolean_t cutinline) 2083 { 2084 spa_t *spa = zio->io_spa; 2085 zio_type_t t = zio->io_type; 2086 2087 /* 2088 * If we're a config writer or a probe, the normal issue and 2089 * interrupt threads may all be blocked waiting for the config lock. 2090 * In this case, select the otherwise-unused taskq for ZIO_TYPE_NULL. 2091 */ 2092 if (zio->io_flags & (ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_PROBE)) 2093 t = ZIO_TYPE_NULL; 2094 2095 /* 2096 * A similar issue exists for the L2ARC write thread until L2ARC 2.0. 2097 */ 2098 if (t == ZIO_TYPE_WRITE && zio->io_vd && zio->io_vd->vdev_aux) 2099 t = ZIO_TYPE_NULL; 2100 2101 /* 2102 * If this is a high priority I/O, then use the high priority taskq if 2103 * available or cut the line otherwise. 2104 */ 2105 if (zio->io_priority == ZIO_PRIORITY_SYNC_WRITE) { 2106 if (spa->spa_zio_taskq[t][q + 1].stqs_count != 0) 2107 q++; 2108 else 2109 cutinline = B_TRUE; 2110 } 2111 2112 ASSERT3U(q, <, ZIO_TASKQ_TYPES); 2113 2114 spa_taskq_dispatch(spa, t, q, zio_execute, zio, cutinline); 2115 } 2116 2117 static boolean_t 2118 zio_taskq_member(zio_t *zio, zio_taskq_type_t q) 2119 { 2120 spa_t *spa = zio->io_spa; 2121 2122 taskq_t *tq = taskq_of_curthread(); 2123 2124 for (zio_type_t t = 0; t < ZIO_TYPES; t++) { 2125 spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q]; 2126 uint_t i; 2127 for (i = 0; i < tqs->stqs_count; i++) { 2128 if (tqs->stqs_taskq[i] == tq) 2129 return (B_TRUE); 2130 } 2131 } 2132 2133 return (B_FALSE); 2134 } 2135 2136 static zio_t * 2137 zio_issue_async(zio_t *zio) 2138 { 2139 ASSERT((zio->io_type != ZIO_TYPE_WRITE) || ZIO_HAS_ALLOCATOR(zio)); 2140 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE); 2141 return (NULL); 2142 } 2143 2144 void 2145 zio_interrupt(void *zio) 2146 { 2147 zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT, B_FALSE); 2148 } 2149 2150 void 2151 zio_delay_interrupt(zio_t *zio) 2152 { 2153 /* 2154 * The timeout_generic() function isn't defined in userspace, so 2155 * rather than trying to implement the function, the zio delay 2156 * functionality has been disabled for userspace builds. 2157 */ 2158 2159 #ifdef _KERNEL 2160 /* 2161 * If io_target_timestamp is zero, then no delay has been registered 2162 * for this IO, thus jump to the end of this function and "skip" the 2163 * delay; issuing it directly to the zio layer. 2164 */ 2165 if (zio->io_target_timestamp != 0) { 2166 hrtime_t now = gethrtime(); 2167 2168 if (now >= zio->io_target_timestamp) { 2169 /* 2170 * This IO has already taken longer than the target 2171 * delay to complete, so we don't want to delay it 2172 * any longer; we "miss" the delay and issue it 2173 * directly to the zio layer. This is likely due to 2174 * the target latency being set to a value less than 2175 * the underlying hardware can satisfy (e.g. delay 2176 * set to 1ms, but the disks take 10ms to complete an 2177 * IO request). 2178 */ 2179 2180 DTRACE_PROBE2(zio__delay__miss, zio_t *, zio, 2181 hrtime_t, now); 2182 2183 zio_interrupt(zio); 2184 } else { 2185 taskqid_t tid; 2186 hrtime_t diff = zio->io_target_timestamp - now; 2187 clock_t expire_at_tick = ddi_get_lbolt() + 2188 NSEC_TO_TICK(diff); 2189 2190 DTRACE_PROBE3(zio__delay__hit, zio_t *, zio, 2191 hrtime_t, now, hrtime_t, diff); 2192 2193 if (NSEC_TO_TICK(diff) == 0) { 2194 /* Our delay is less than a jiffy - just spin */ 2195 zfs_sleep_until(zio->io_target_timestamp); 2196 zio_interrupt(zio); 2197 } else { 2198 /* 2199 * Use taskq_dispatch_delay() in the place of 2200 * OpenZFS's timeout_generic(). 2201 */ 2202 tid = taskq_dispatch_delay(system_taskq, 2203 zio_interrupt, zio, TQ_NOSLEEP, 2204 expire_at_tick); 2205 if (tid == TASKQID_INVALID) { 2206 /* 2207 * Couldn't allocate a task. Just 2208 * finish the zio without a delay. 2209 */ 2210 zio_interrupt(zio); 2211 } 2212 } 2213 } 2214 return; 2215 } 2216 #endif 2217 DTRACE_PROBE1(zio__delay__skip, zio_t *, zio); 2218 zio_interrupt(zio); 2219 } 2220 2221 static void 2222 zio_deadman_impl(zio_t *pio, int ziodepth) 2223 { 2224 zio_t *cio, *cio_next; 2225 zio_link_t *zl = NULL; 2226 vdev_t *vd = pio->io_vd; 2227 2228 if (zio_deadman_log_all || (vd != NULL && vd->vdev_ops->vdev_op_leaf)) { 2229 vdev_queue_t *vq = vd ? &vd->vdev_queue : NULL; 2230 zbookmark_phys_t *zb = &pio->io_bookmark; 2231 uint64_t delta = gethrtime() - pio->io_timestamp; 2232 uint64_t failmode = spa_get_deadman_failmode(pio->io_spa); 2233 2234 zfs_dbgmsg("slow zio[%d]: zio=%px timestamp=%llu " 2235 "delta=%llu queued=%llu io=%llu " 2236 "path=%s " 2237 "last=%llu type=%d " 2238 "priority=%d flags=0x%llx stage=0x%x " 2239 "pipeline=0x%x pipeline-trace=0x%x " 2240 "objset=%llu object=%llu " 2241 "level=%llu blkid=%llu " 2242 "offset=%llu size=%llu " 2243 "error=%d", 2244 ziodepth, pio, pio->io_timestamp, 2245 (u_longlong_t)delta, pio->io_delta, pio->io_delay, 2246 vd ? vd->vdev_path : "NULL", 2247 vq ? vq->vq_io_complete_ts : 0, pio->io_type, 2248 pio->io_priority, (u_longlong_t)pio->io_flags, 2249 pio->io_stage, pio->io_pipeline, pio->io_pipeline_trace, 2250 (u_longlong_t)zb->zb_objset, (u_longlong_t)zb->zb_object, 2251 (u_longlong_t)zb->zb_level, (u_longlong_t)zb->zb_blkid, 2252 (u_longlong_t)pio->io_offset, (u_longlong_t)pio->io_size, 2253 pio->io_error); 2254 (void) zfs_ereport_post(FM_EREPORT_ZFS_DEADMAN, 2255 pio->io_spa, vd, zb, pio, 0); 2256 2257 if (failmode == ZIO_FAILURE_MODE_CONTINUE && 2258 taskq_empty_ent(&pio->io_tqent)) { 2259 zio_interrupt(pio); 2260 } 2261 } 2262 2263 mutex_enter(&pio->io_lock); 2264 for (cio = zio_walk_children(pio, &zl); cio != NULL; cio = cio_next) { 2265 cio_next = zio_walk_children(pio, &zl); 2266 zio_deadman_impl(cio, ziodepth + 1); 2267 } 2268 mutex_exit(&pio->io_lock); 2269 } 2270 2271 /* 2272 * Log the critical information describing this zio and all of its children 2273 * using the zfs_dbgmsg() interface then post deadman event for the ZED. 2274 */ 2275 void 2276 zio_deadman(zio_t *pio, const char *tag) 2277 { 2278 spa_t *spa = pio->io_spa; 2279 char *name = spa_name(spa); 2280 2281 if (!zfs_deadman_enabled || spa_suspended(spa)) 2282 return; 2283 2284 zio_deadman_impl(pio, 0); 2285 2286 switch (spa_get_deadman_failmode(spa)) { 2287 case ZIO_FAILURE_MODE_WAIT: 2288 zfs_dbgmsg("%s waiting for hung I/O to pool '%s'", tag, name); 2289 break; 2290 2291 case ZIO_FAILURE_MODE_CONTINUE: 2292 zfs_dbgmsg("%s restarting hung I/O for pool '%s'", tag, name); 2293 break; 2294 2295 case ZIO_FAILURE_MODE_PANIC: 2296 fm_panic("%s determined I/O to pool '%s' is hung.", tag, name); 2297 break; 2298 } 2299 } 2300 2301 /* 2302 * Execute the I/O pipeline until one of the following occurs: 2303 * (1) the I/O completes; (2) the pipeline stalls waiting for 2304 * dependent child I/Os; (3) the I/O issues, so we're waiting 2305 * for an I/O completion interrupt; (4) the I/O is delegated by 2306 * vdev-level caching or aggregation; (5) the I/O is deferred 2307 * due to vdev-level queueing; (6) the I/O is handed off to 2308 * another thread. In all cases, the pipeline stops whenever 2309 * there's no CPU work; it never burns a thread in cv_wait_io(). 2310 * 2311 * There's no locking on io_stage because there's no legitimate way 2312 * for multiple threads to be attempting to process the same I/O. 2313 */ 2314 static zio_pipe_stage_t *zio_pipeline[]; 2315 2316 /* 2317 * zio_execute() is a wrapper around the static function 2318 * __zio_execute() so that we can force __zio_execute() to be 2319 * inlined. This reduces stack overhead which is important 2320 * because __zio_execute() is called recursively in several zio 2321 * code paths. zio_execute() itself cannot be inlined because 2322 * it is externally visible. 2323 */ 2324 void 2325 zio_execute(void *zio) 2326 { 2327 fstrans_cookie_t cookie; 2328 2329 cookie = spl_fstrans_mark(); 2330 __zio_execute(zio); 2331 spl_fstrans_unmark(cookie); 2332 } 2333 2334 /* 2335 * Used to determine if in the current context the stack is sized large 2336 * enough to allow zio_execute() to be called recursively. A minimum 2337 * stack size of 16K is required to avoid needing to re-dispatch the zio. 2338 */ 2339 static boolean_t 2340 zio_execute_stack_check(zio_t *zio) 2341 { 2342 #if !defined(HAVE_LARGE_STACKS) 2343 dsl_pool_t *dp = spa_get_dsl(zio->io_spa); 2344 2345 /* Executing in txg_sync_thread() context. */ 2346 if (dp && curthread == dp->dp_tx.tx_sync_thread) 2347 return (B_TRUE); 2348 2349 /* Pool initialization outside of zio_taskq context. */ 2350 if (dp && spa_is_initializing(dp->dp_spa) && 2351 !zio_taskq_member(zio, ZIO_TASKQ_ISSUE) && 2352 !zio_taskq_member(zio, ZIO_TASKQ_ISSUE_HIGH)) 2353 return (B_TRUE); 2354 #else 2355 (void) zio; 2356 #endif /* HAVE_LARGE_STACKS */ 2357 2358 return (B_FALSE); 2359 } 2360 2361 __attribute__((always_inline)) 2362 static inline void 2363 __zio_execute(zio_t *zio) 2364 { 2365 ASSERT3U(zio->io_queued_timestamp, >, 0); 2366 2367 while (zio->io_stage < ZIO_STAGE_DONE) { 2368 enum zio_stage pipeline = zio->io_pipeline; 2369 enum zio_stage stage = zio->io_stage; 2370 2371 zio->io_executor = curthread; 2372 2373 ASSERT(!MUTEX_HELD(&zio->io_lock)); 2374 ASSERT(ISP2(stage)); 2375 ASSERT(zio->io_stall == NULL); 2376 2377 do { 2378 stage <<= 1; 2379 } while ((stage & pipeline) == 0); 2380 2381 ASSERT(stage <= ZIO_STAGE_DONE); 2382 2383 /* 2384 * If we are in interrupt context and this pipeline stage 2385 * will grab a config lock that is held across I/O, 2386 * or may wait for an I/O that needs an interrupt thread 2387 * to complete, issue async to avoid deadlock. 2388 * 2389 * For VDEV_IO_START, we cut in line so that the io will 2390 * be sent to disk promptly. 2391 */ 2392 if ((stage & ZIO_BLOCKING_STAGES) && zio->io_vd == NULL && 2393 zio_taskq_member(zio, ZIO_TASKQ_INTERRUPT)) { 2394 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ? 2395 zio_requeue_io_start_cut_in_line : B_FALSE; 2396 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut); 2397 return; 2398 } 2399 2400 /* 2401 * If the current context doesn't have large enough stacks 2402 * the zio must be issued asynchronously to prevent overflow. 2403 */ 2404 if (zio_execute_stack_check(zio)) { 2405 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ? 2406 zio_requeue_io_start_cut_in_line : B_FALSE; 2407 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut); 2408 return; 2409 } 2410 2411 zio->io_stage = stage; 2412 zio->io_pipeline_trace |= zio->io_stage; 2413 2414 /* 2415 * The zio pipeline stage returns the next zio to execute 2416 * (typically the same as this one), or NULL if we should 2417 * stop. 2418 */ 2419 zio = zio_pipeline[highbit64(stage) - 1](zio); 2420 2421 if (zio == NULL) 2422 return; 2423 } 2424 } 2425 2426 2427 /* 2428 * ========================================================================== 2429 * Initiate I/O, either sync or async 2430 * ========================================================================== 2431 */ 2432 int 2433 zio_wait(zio_t *zio) 2434 { 2435 /* 2436 * Some routines, like zio_free_sync(), may return a NULL zio 2437 * to avoid the performance overhead of creating and then destroying 2438 * an unneeded zio. For the callers' simplicity, we accept a NULL 2439 * zio and ignore it. 2440 */ 2441 if (zio == NULL) 2442 return (0); 2443 2444 long timeout = MSEC_TO_TICK(zfs_deadman_ziotime_ms); 2445 int error; 2446 2447 ASSERT3S(zio->io_stage, ==, ZIO_STAGE_OPEN); 2448 ASSERT3P(zio->io_executor, ==, NULL); 2449 2450 zio->io_waiter = curthread; 2451 ASSERT0(zio->io_queued_timestamp); 2452 zio->io_queued_timestamp = gethrtime(); 2453 2454 if (zio->io_type == ZIO_TYPE_WRITE) { 2455 spa_select_allocator(zio); 2456 } 2457 __zio_execute(zio); 2458 2459 mutex_enter(&zio->io_lock); 2460 while (zio->io_executor != NULL) { 2461 error = cv_timedwait_io(&zio->io_cv, &zio->io_lock, 2462 ddi_get_lbolt() + timeout); 2463 2464 if (zfs_deadman_enabled && error == -1 && 2465 gethrtime() - zio->io_queued_timestamp > 2466 spa_deadman_ziotime(zio->io_spa)) { 2467 mutex_exit(&zio->io_lock); 2468 timeout = MSEC_TO_TICK(zfs_deadman_checktime_ms); 2469 zio_deadman(zio, FTAG); 2470 mutex_enter(&zio->io_lock); 2471 } 2472 } 2473 mutex_exit(&zio->io_lock); 2474 2475 error = zio->io_error; 2476 zio_destroy(zio); 2477 2478 return (error); 2479 } 2480 2481 void 2482 zio_nowait(zio_t *zio) 2483 { 2484 /* 2485 * See comment in zio_wait(). 2486 */ 2487 if (zio == NULL) 2488 return; 2489 2490 ASSERT3P(zio->io_executor, ==, NULL); 2491 2492 if (zio->io_child_type == ZIO_CHILD_LOGICAL && 2493 list_is_empty(&zio->io_parent_list)) { 2494 zio_t *pio; 2495 2496 /* 2497 * This is a logical async I/O with no parent to wait for it. 2498 * We add it to the spa_async_root_zio "Godfather" I/O which 2499 * will ensure they complete prior to unloading the pool. 2500 */ 2501 spa_t *spa = zio->io_spa; 2502 pio = spa->spa_async_zio_root[CPU_SEQID_UNSTABLE]; 2503 2504 zio_add_child(pio, zio); 2505 } 2506 2507 ASSERT0(zio->io_queued_timestamp); 2508 zio->io_queued_timestamp = gethrtime(); 2509 if (zio->io_type == ZIO_TYPE_WRITE) { 2510 spa_select_allocator(zio); 2511 } 2512 __zio_execute(zio); 2513 } 2514 2515 /* 2516 * ========================================================================== 2517 * Reexecute, cancel, or suspend/resume failed I/O 2518 * ========================================================================== 2519 */ 2520 2521 static void 2522 zio_reexecute(void *arg) 2523 { 2524 zio_t *pio = arg; 2525 zio_t *cio, *cio_next, *gio; 2526 2527 ASSERT(pio->io_child_type == ZIO_CHILD_LOGICAL); 2528 ASSERT(pio->io_orig_stage == ZIO_STAGE_OPEN); 2529 ASSERT(pio->io_gang_leader == NULL); 2530 ASSERT(pio->io_gang_tree == NULL); 2531 2532 mutex_enter(&pio->io_lock); 2533 pio->io_flags = pio->io_orig_flags; 2534 pio->io_stage = pio->io_orig_stage; 2535 pio->io_pipeline = pio->io_orig_pipeline; 2536 pio->io_reexecute = 0; 2537 pio->io_flags |= ZIO_FLAG_REEXECUTED; 2538 pio->io_pipeline_trace = 0; 2539 pio->io_error = 0; 2540 pio->io_state[ZIO_WAIT_READY] = (pio->io_stage >= ZIO_STAGE_READY) || 2541 (pio->io_pipeline & ZIO_STAGE_READY) == 0; 2542 pio->io_state[ZIO_WAIT_DONE] = (pio->io_stage >= ZIO_STAGE_DONE); 2543 zio_link_t *zl = NULL; 2544 while ((gio = zio_walk_parents(pio, &zl)) != NULL) { 2545 for (int w = 0; w < ZIO_WAIT_TYPES; w++) { 2546 gio->io_children[pio->io_child_type][w] += 2547 !pio->io_state[w]; 2548 } 2549 } 2550 for (int c = 0; c < ZIO_CHILD_TYPES; c++) 2551 pio->io_child_error[c] = 0; 2552 2553 if (IO_IS_ALLOCATING(pio)) 2554 BP_ZERO(pio->io_bp); 2555 2556 /* 2557 * As we reexecute pio's children, new children could be created. 2558 * New children go to the head of pio's io_child_list, however, 2559 * so we will (correctly) not reexecute them. The key is that 2560 * the remainder of pio's io_child_list, from 'cio_next' onward, 2561 * cannot be affected by any side effects of reexecuting 'cio'. 2562 */ 2563 zl = NULL; 2564 for (cio = zio_walk_children(pio, &zl); cio != NULL; cio = cio_next) { 2565 cio_next = zio_walk_children(pio, &zl); 2566 mutex_exit(&pio->io_lock); 2567 zio_reexecute(cio); 2568 mutex_enter(&pio->io_lock); 2569 } 2570 mutex_exit(&pio->io_lock); 2571 2572 /* 2573 * Now that all children have been reexecuted, execute the parent. 2574 * We don't reexecute "The Godfather" I/O here as it's the 2575 * responsibility of the caller to wait on it. 2576 */ 2577 if (!(pio->io_flags & ZIO_FLAG_GODFATHER)) { 2578 pio->io_queued_timestamp = gethrtime(); 2579 __zio_execute(pio); 2580 } 2581 } 2582 2583 void 2584 zio_suspend(spa_t *spa, zio_t *zio, zio_suspend_reason_t reason) 2585 { 2586 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC) 2587 fm_panic("Pool '%s' has encountered an uncorrectable I/O " 2588 "failure and the failure mode property for this pool " 2589 "is set to panic.", spa_name(spa)); 2590 2591 if (reason != ZIO_SUSPEND_MMP) { 2592 cmn_err(CE_WARN, "Pool '%s' has encountered an uncorrectable " 2593 "I/O failure and has been suspended.", spa_name(spa)); 2594 } 2595 2596 (void) zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, 2597 NULL, NULL, 0); 2598 2599 mutex_enter(&spa->spa_suspend_lock); 2600 2601 if (spa->spa_suspend_zio_root == NULL) 2602 spa->spa_suspend_zio_root = zio_root(spa, NULL, NULL, 2603 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | 2604 ZIO_FLAG_GODFATHER); 2605 2606 spa->spa_suspended = reason; 2607 2608 if (zio != NULL) { 2609 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER)); 2610 ASSERT(zio != spa->spa_suspend_zio_root); 2611 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 2612 ASSERT(zio_unique_parent(zio) == NULL); 2613 ASSERT(zio->io_stage == ZIO_STAGE_DONE); 2614 zio_add_child(spa->spa_suspend_zio_root, zio); 2615 } 2616 2617 mutex_exit(&spa->spa_suspend_lock); 2618 } 2619 2620 int 2621 zio_resume(spa_t *spa) 2622 { 2623 zio_t *pio; 2624 2625 /* 2626 * Reexecute all previously suspended i/o. 2627 */ 2628 mutex_enter(&spa->spa_suspend_lock); 2629 if (spa->spa_suspended != ZIO_SUSPEND_NONE) 2630 cmn_err(CE_WARN, "Pool '%s' was suspended and is being " 2631 "resumed. Failed I/O will be retried.", 2632 spa_name(spa)); 2633 spa->spa_suspended = ZIO_SUSPEND_NONE; 2634 cv_broadcast(&spa->spa_suspend_cv); 2635 pio = spa->spa_suspend_zio_root; 2636 spa->spa_suspend_zio_root = NULL; 2637 mutex_exit(&spa->spa_suspend_lock); 2638 2639 if (pio == NULL) 2640 return (0); 2641 2642 zio_reexecute(pio); 2643 return (zio_wait(pio)); 2644 } 2645 2646 void 2647 zio_resume_wait(spa_t *spa) 2648 { 2649 mutex_enter(&spa->spa_suspend_lock); 2650 while (spa_suspended(spa)) 2651 cv_wait(&spa->spa_suspend_cv, &spa->spa_suspend_lock); 2652 mutex_exit(&spa->spa_suspend_lock); 2653 } 2654 2655 /* 2656 * ========================================================================== 2657 * Gang blocks. 2658 * 2659 * A gang block is a collection of small blocks that looks to the DMU 2660 * like one large block. When zio_dva_allocate() cannot find a block 2661 * of the requested size, due to either severe fragmentation or the pool 2662 * being nearly full, it calls zio_write_gang_block() to construct the 2663 * block from smaller fragments. 2664 * 2665 * A gang block consists of a gang header (zio_gbh_phys_t) and up to 2666 * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like 2667 * an indirect block: it's an array of block pointers. It consumes 2668 * only one sector and hence is allocatable regardless of fragmentation. 2669 * The gang header's bps point to its gang members, which hold the data. 2670 * 2671 * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg> 2672 * as the verifier to ensure uniqueness of the SHA256 checksum. 2673 * Critically, the gang block bp's blk_cksum is the checksum of the data, 2674 * not the gang header. This ensures that data block signatures (needed for 2675 * deduplication) are independent of how the block is physically stored. 2676 * 2677 * Gang blocks can be nested: a gang member may itself be a gang block. 2678 * Thus every gang block is a tree in which root and all interior nodes are 2679 * gang headers, and the leaves are normal blocks that contain user data. 2680 * The root of the gang tree is called the gang leader. 2681 * 2682 * To perform any operation (read, rewrite, free, claim) on a gang block, 2683 * zio_gang_assemble() first assembles the gang tree (minus data leaves) 2684 * in the io_gang_tree field of the original logical i/o by recursively 2685 * reading the gang leader and all gang headers below it. This yields 2686 * an in-core tree containing the contents of every gang header and the 2687 * bps for every constituent of the gang block. 2688 * 2689 * With the gang tree now assembled, zio_gang_issue() just walks the gang tree 2690 * and invokes a callback on each bp. To free a gang block, zio_gang_issue() 2691 * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp. 2692 * zio_claim_gang() provides a similarly trivial wrapper for zio_claim(). 2693 * zio_read_gang() is a wrapper around zio_read() that omits reading gang 2694 * headers, since we already have those in io_gang_tree. zio_rewrite_gang() 2695 * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite() 2696 * of the gang header plus zio_checksum_compute() of the data to update the 2697 * gang header's blk_cksum as described above. 2698 * 2699 * The two-phase assemble/issue model solves the problem of partial failure -- 2700 * what if you'd freed part of a gang block but then couldn't read the 2701 * gang header for another part? Assembling the entire gang tree first 2702 * ensures that all the necessary gang header I/O has succeeded before 2703 * starting the actual work of free, claim, or write. Once the gang tree 2704 * is assembled, free and claim are in-memory operations that cannot fail. 2705 * 2706 * In the event that a gang write fails, zio_dva_unallocate() walks the 2707 * gang tree to immediately free (i.e. insert back into the space map) 2708 * everything we've allocated. This ensures that we don't get ENOSPC 2709 * errors during repeated suspend/resume cycles due to a flaky device. 2710 * 2711 * Gang rewrites only happen during sync-to-convergence. If we can't assemble 2712 * the gang tree, we won't modify the block, so we can safely defer the free 2713 * (knowing that the block is still intact). If we *can* assemble the gang 2714 * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free 2715 * each constituent bp and we can allocate a new block on the next sync pass. 2716 * 2717 * In all cases, the gang tree allows complete recovery from partial failure. 2718 * ========================================================================== 2719 */ 2720 2721 static void 2722 zio_gang_issue_func_done(zio_t *zio) 2723 { 2724 abd_free(zio->io_abd); 2725 } 2726 2727 static zio_t * 2728 zio_read_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2729 uint64_t offset) 2730 { 2731 if (gn != NULL) 2732 return (pio); 2733 2734 return (zio_read(pio, pio->io_spa, bp, abd_get_offset(data, offset), 2735 BP_GET_PSIZE(bp), zio_gang_issue_func_done, 2736 NULL, pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), 2737 &pio->io_bookmark)); 2738 } 2739 2740 static zio_t * 2741 zio_rewrite_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2742 uint64_t offset) 2743 { 2744 zio_t *zio; 2745 2746 if (gn != NULL) { 2747 abd_t *gbh_abd = 2748 abd_get_from_buf(gn->gn_gbh, SPA_GANGBLOCKSIZE); 2749 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp, 2750 gbh_abd, SPA_GANGBLOCKSIZE, zio_gang_issue_func_done, NULL, 2751 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), 2752 &pio->io_bookmark); 2753 /* 2754 * As we rewrite each gang header, the pipeline will compute 2755 * a new gang block header checksum for it; but no one will 2756 * compute a new data checksum, so we do that here. The one 2757 * exception is the gang leader: the pipeline already computed 2758 * its data checksum because that stage precedes gang assembly. 2759 * (Presently, nothing actually uses interior data checksums; 2760 * this is just good hygiene.) 2761 */ 2762 if (gn != pio->io_gang_leader->io_gang_tree) { 2763 abd_t *buf = abd_get_offset(data, offset); 2764 2765 zio_checksum_compute(zio, BP_GET_CHECKSUM(bp), 2766 buf, BP_GET_PSIZE(bp)); 2767 2768 abd_free(buf); 2769 } 2770 /* 2771 * If we are here to damage data for testing purposes, 2772 * leave the GBH alone so that we can detect the damage. 2773 */ 2774 if (pio->io_gang_leader->io_flags & ZIO_FLAG_INDUCE_DAMAGE) 2775 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES; 2776 } else { 2777 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp, 2778 abd_get_offset(data, offset), BP_GET_PSIZE(bp), 2779 zio_gang_issue_func_done, NULL, pio->io_priority, 2780 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 2781 } 2782 2783 return (zio); 2784 } 2785 2786 static zio_t * 2787 zio_free_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2788 uint64_t offset) 2789 { 2790 (void) gn, (void) data, (void) offset; 2791 2792 zio_t *zio = zio_free_sync(pio, pio->io_spa, pio->io_txg, bp, 2793 ZIO_GANG_CHILD_FLAGS(pio)); 2794 if (zio == NULL) { 2795 zio = zio_null(pio, pio->io_spa, 2796 NULL, NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio)); 2797 } 2798 return (zio); 2799 } 2800 2801 static zio_t * 2802 zio_claim_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data, 2803 uint64_t offset) 2804 { 2805 (void) gn, (void) data, (void) offset; 2806 return (zio_claim(pio, pio->io_spa, pio->io_txg, bp, 2807 NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio))); 2808 } 2809 2810 static zio_gang_issue_func_t *zio_gang_issue_func[ZIO_TYPES] = { 2811 NULL, 2812 zio_read_gang, 2813 zio_rewrite_gang, 2814 zio_free_gang, 2815 zio_claim_gang, 2816 NULL 2817 }; 2818 2819 static void zio_gang_tree_assemble_done(zio_t *zio); 2820 2821 static zio_gang_node_t * 2822 zio_gang_node_alloc(zio_gang_node_t **gnpp) 2823 { 2824 zio_gang_node_t *gn; 2825 2826 ASSERT(*gnpp == NULL); 2827 2828 gn = kmem_zalloc(sizeof (*gn), KM_SLEEP); 2829 gn->gn_gbh = zio_buf_alloc(SPA_GANGBLOCKSIZE); 2830 *gnpp = gn; 2831 2832 return (gn); 2833 } 2834 2835 static void 2836 zio_gang_node_free(zio_gang_node_t **gnpp) 2837 { 2838 zio_gang_node_t *gn = *gnpp; 2839 2840 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) 2841 ASSERT(gn->gn_child[g] == NULL); 2842 2843 zio_buf_free(gn->gn_gbh, SPA_GANGBLOCKSIZE); 2844 kmem_free(gn, sizeof (*gn)); 2845 *gnpp = NULL; 2846 } 2847 2848 static void 2849 zio_gang_tree_free(zio_gang_node_t **gnpp) 2850 { 2851 zio_gang_node_t *gn = *gnpp; 2852 2853 if (gn == NULL) 2854 return; 2855 2856 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) 2857 zio_gang_tree_free(&gn->gn_child[g]); 2858 2859 zio_gang_node_free(gnpp); 2860 } 2861 2862 static void 2863 zio_gang_tree_assemble(zio_t *gio, blkptr_t *bp, zio_gang_node_t **gnpp) 2864 { 2865 zio_gang_node_t *gn = zio_gang_node_alloc(gnpp); 2866 abd_t *gbh_abd = abd_get_from_buf(gn->gn_gbh, SPA_GANGBLOCKSIZE); 2867 2868 ASSERT(gio->io_gang_leader == gio); 2869 ASSERT(BP_IS_GANG(bp)); 2870 2871 zio_nowait(zio_read(gio, gio->io_spa, bp, gbh_abd, SPA_GANGBLOCKSIZE, 2872 zio_gang_tree_assemble_done, gn, gio->io_priority, 2873 ZIO_GANG_CHILD_FLAGS(gio), &gio->io_bookmark)); 2874 } 2875 2876 static void 2877 zio_gang_tree_assemble_done(zio_t *zio) 2878 { 2879 zio_t *gio = zio->io_gang_leader; 2880 zio_gang_node_t *gn = zio->io_private; 2881 blkptr_t *bp = zio->io_bp; 2882 2883 ASSERT(gio == zio_unique_parent(zio)); 2884 ASSERT(list_is_empty(&zio->io_child_list)); 2885 2886 if (zio->io_error) 2887 return; 2888 2889 /* this ABD was created from a linear buf in zio_gang_tree_assemble */ 2890 if (BP_SHOULD_BYTESWAP(bp)) 2891 byteswap_uint64_array(abd_to_buf(zio->io_abd), zio->io_size); 2892 2893 ASSERT3P(abd_to_buf(zio->io_abd), ==, gn->gn_gbh); 2894 ASSERT(zio->io_size == SPA_GANGBLOCKSIZE); 2895 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC); 2896 2897 abd_free(zio->io_abd); 2898 2899 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 2900 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g]; 2901 if (!BP_IS_GANG(gbp)) 2902 continue; 2903 zio_gang_tree_assemble(gio, gbp, &gn->gn_child[g]); 2904 } 2905 } 2906 2907 static void 2908 zio_gang_tree_issue(zio_t *pio, zio_gang_node_t *gn, blkptr_t *bp, abd_t *data, 2909 uint64_t offset) 2910 { 2911 zio_t *gio = pio->io_gang_leader; 2912 zio_t *zio; 2913 2914 ASSERT(BP_IS_GANG(bp) == !!gn); 2915 ASSERT(BP_GET_CHECKSUM(bp) == BP_GET_CHECKSUM(gio->io_bp)); 2916 ASSERT(BP_GET_LSIZE(bp) == BP_GET_PSIZE(bp) || gn == gio->io_gang_tree); 2917 2918 /* 2919 * If you're a gang header, your data is in gn->gn_gbh. 2920 * If you're a gang member, your data is in 'data' and gn == NULL. 2921 */ 2922 zio = zio_gang_issue_func[gio->io_type](pio, bp, gn, data, offset); 2923 2924 if (gn != NULL) { 2925 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC); 2926 2927 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 2928 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g]; 2929 if (BP_IS_HOLE(gbp)) 2930 continue; 2931 zio_gang_tree_issue(zio, gn->gn_child[g], gbp, data, 2932 offset); 2933 offset += BP_GET_PSIZE(gbp); 2934 } 2935 } 2936 2937 if (gn == gio->io_gang_tree) 2938 ASSERT3U(gio->io_size, ==, offset); 2939 2940 if (zio != pio) 2941 zio_nowait(zio); 2942 } 2943 2944 static zio_t * 2945 zio_gang_assemble(zio_t *zio) 2946 { 2947 blkptr_t *bp = zio->io_bp; 2948 2949 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == NULL); 2950 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 2951 2952 zio->io_gang_leader = zio; 2953 2954 zio_gang_tree_assemble(zio, bp, &zio->io_gang_tree); 2955 2956 return (zio); 2957 } 2958 2959 static zio_t * 2960 zio_gang_issue(zio_t *zio) 2961 { 2962 blkptr_t *bp = zio->io_bp; 2963 2964 if (zio_wait_for_children(zio, ZIO_CHILD_GANG_BIT, ZIO_WAIT_DONE)) { 2965 return (NULL); 2966 } 2967 2968 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == zio); 2969 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 2970 2971 if (zio->io_child_error[ZIO_CHILD_GANG] == 0) 2972 zio_gang_tree_issue(zio, zio->io_gang_tree, bp, zio->io_abd, 2973 0); 2974 else 2975 zio_gang_tree_free(&zio->io_gang_tree); 2976 2977 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 2978 2979 return (zio); 2980 } 2981 2982 static void 2983 zio_gang_inherit_allocator(zio_t *pio, zio_t *cio) 2984 { 2985 cio->io_allocator = pio->io_allocator; 2986 } 2987 2988 static void 2989 zio_write_gang_member_ready(zio_t *zio) 2990 { 2991 zio_t *pio = zio_unique_parent(zio); 2992 dva_t *cdva = zio->io_bp->blk_dva; 2993 dva_t *pdva = pio->io_bp->blk_dva; 2994 uint64_t asize; 2995 zio_t *gio __maybe_unused = zio->io_gang_leader; 2996 2997 if (BP_IS_HOLE(zio->io_bp)) 2998 return; 2999 3000 ASSERT(BP_IS_HOLE(&zio->io_bp_orig)); 3001 3002 ASSERT(zio->io_child_type == ZIO_CHILD_GANG); 3003 ASSERT3U(zio->io_prop.zp_copies, ==, gio->io_prop.zp_copies); 3004 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(zio->io_bp)); 3005 ASSERT3U(pio->io_prop.zp_copies, <=, BP_GET_NDVAS(pio->io_bp)); 3006 VERIFY3U(BP_GET_NDVAS(zio->io_bp), <=, BP_GET_NDVAS(pio->io_bp)); 3007 3008 mutex_enter(&pio->io_lock); 3009 for (int d = 0; d < BP_GET_NDVAS(zio->io_bp); d++) { 3010 ASSERT(DVA_GET_GANG(&pdva[d])); 3011 asize = DVA_GET_ASIZE(&pdva[d]); 3012 asize += DVA_GET_ASIZE(&cdva[d]); 3013 DVA_SET_ASIZE(&pdva[d], asize); 3014 } 3015 mutex_exit(&pio->io_lock); 3016 } 3017 3018 static void 3019 zio_write_gang_done(zio_t *zio) 3020 { 3021 /* 3022 * The io_abd field will be NULL for a zio with no data. The io_flags 3023 * will initially have the ZIO_FLAG_NODATA bit flag set, but we can't 3024 * check for it here as it is cleared in zio_ready. 3025 */ 3026 if (zio->io_abd != NULL) 3027 abd_free(zio->io_abd); 3028 } 3029 3030 static zio_t * 3031 zio_write_gang_block(zio_t *pio, metaslab_class_t *mc) 3032 { 3033 spa_t *spa = pio->io_spa; 3034 blkptr_t *bp = pio->io_bp; 3035 zio_t *gio = pio->io_gang_leader; 3036 zio_t *zio; 3037 zio_gang_node_t *gn, **gnpp; 3038 zio_gbh_phys_t *gbh; 3039 abd_t *gbh_abd; 3040 uint64_t txg = pio->io_txg; 3041 uint64_t resid = pio->io_size; 3042 uint64_t lsize; 3043 int copies = gio->io_prop.zp_copies; 3044 zio_prop_t zp; 3045 int error; 3046 boolean_t has_data = !(pio->io_flags & ZIO_FLAG_NODATA); 3047 3048 /* 3049 * If one copy was requested, store 2 copies of the GBH, so that we 3050 * can still traverse all the data (e.g. to free or scrub) even if a 3051 * block is damaged. Note that we can't store 3 copies of the GBH in 3052 * all cases, e.g. with encryption, which uses DVA[2] for the IV+salt. 3053 */ 3054 int gbh_copies = copies; 3055 if (gbh_copies == 1) { 3056 gbh_copies = MIN(2, spa_max_replication(spa)); 3057 } 3058 3059 ASSERT(ZIO_HAS_ALLOCATOR(pio)); 3060 int flags = METASLAB_HINTBP_FAVOR | METASLAB_GANG_HEADER; 3061 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 3062 ASSERT(pio->io_priority == ZIO_PRIORITY_ASYNC_WRITE); 3063 ASSERT(has_data); 3064 3065 flags |= METASLAB_ASYNC_ALLOC; 3066 VERIFY(zfs_refcount_held(&mc->mc_allocator[pio->io_allocator]. 3067 mca_alloc_slots, pio)); 3068 3069 /* 3070 * The logical zio has already placed a reservation for 3071 * 'copies' allocation slots but gang blocks may require 3072 * additional copies. These additional copies 3073 * (i.e. gbh_copies - copies) are guaranteed to succeed 3074 * since metaslab_class_throttle_reserve() always allows 3075 * additional reservations for gang blocks. 3076 */ 3077 VERIFY(metaslab_class_throttle_reserve(mc, gbh_copies - copies, 3078 pio->io_allocator, pio, flags)); 3079 } 3080 3081 error = metaslab_alloc(spa, mc, SPA_GANGBLOCKSIZE, 3082 bp, gbh_copies, txg, pio == gio ? NULL : gio->io_bp, flags, 3083 &pio->io_alloc_list, pio, pio->io_allocator); 3084 if (error) { 3085 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 3086 ASSERT(pio->io_priority == ZIO_PRIORITY_ASYNC_WRITE); 3087 ASSERT(has_data); 3088 3089 /* 3090 * If we failed to allocate the gang block header then 3091 * we remove any additional allocation reservations that 3092 * we placed here. The original reservation will 3093 * be removed when the logical I/O goes to the ready 3094 * stage. 3095 */ 3096 metaslab_class_throttle_unreserve(mc, 3097 gbh_copies - copies, pio->io_allocator, pio); 3098 } 3099 3100 pio->io_error = error; 3101 return (pio); 3102 } 3103 3104 if (pio == gio) { 3105 gnpp = &gio->io_gang_tree; 3106 } else { 3107 gnpp = pio->io_private; 3108 ASSERT(pio->io_ready == zio_write_gang_member_ready); 3109 } 3110 3111 gn = zio_gang_node_alloc(gnpp); 3112 gbh = gn->gn_gbh; 3113 memset(gbh, 0, SPA_GANGBLOCKSIZE); 3114 gbh_abd = abd_get_from_buf(gbh, SPA_GANGBLOCKSIZE); 3115 3116 /* 3117 * Create the gang header. 3118 */ 3119 zio = zio_rewrite(pio, spa, txg, bp, gbh_abd, SPA_GANGBLOCKSIZE, 3120 zio_write_gang_done, NULL, pio->io_priority, 3121 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 3122 3123 zio_gang_inherit_allocator(pio, zio); 3124 3125 /* 3126 * Create and nowait the gang children. 3127 */ 3128 for (int g = 0; resid != 0; resid -= lsize, g++) { 3129 lsize = P2ROUNDUP(resid / (SPA_GBH_NBLKPTRS - g), 3130 SPA_MINBLOCKSIZE); 3131 ASSERT(lsize >= SPA_MINBLOCKSIZE && lsize <= resid); 3132 3133 zp.zp_checksum = gio->io_prop.zp_checksum; 3134 zp.zp_compress = ZIO_COMPRESS_OFF; 3135 zp.zp_complevel = gio->io_prop.zp_complevel; 3136 zp.zp_type = zp.zp_storage_type = DMU_OT_NONE; 3137 zp.zp_level = 0; 3138 zp.zp_copies = gio->io_prop.zp_copies; 3139 zp.zp_dedup = B_FALSE; 3140 zp.zp_dedup_verify = B_FALSE; 3141 zp.zp_nopwrite = B_FALSE; 3142 zp.zp_encrypt = gio->io_prop.zp_encrypt; 3143 zp.zp_byteorder = gio->io_prop.zp_byteorder; 3144 zp.zp_direct_write = B_FALSE; 3145 memset(zp.zp_salt, 0, ZIO_DATA_SALT_LEN); 3146 memset(zp.zp_iv, 0, ZIO_DATA_IV_LEN); 3147 memset(zp.zp_mac, 0, ZIO_DATA_MAC_LEN); 3148 3149 zio_t *cio = zio_write(zio, spa, txg, &gbh->zg_blkptr[g], 3150 has_data ? abd_get_offset(pio->io_abd, pio->io_size - 3151 resid) : NULL, lsize, lsize, &zp, 3152 zio_write_gang_member_ready, NULL, 3153 zio_write_gang_done, &gn->gn_child[g], pio->io_priority, 3154 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark); 3155 3156 zio_gang_inherit_allocator(zio, cio); 3157 3158 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 3159 ASSERT(pio->io_priority == ZIO_PRIORITY_ASYNC_WRITE); 3160 ASSERT(has_data); 3161 3162 /* 3163 * Gang children won't throttle but we should 3164 * account for their work, so reserve an allocation 3165 * slot for them here. 3166 */ 3167 VERIFY(metaslab_class_throttle_reserve(mc, 3168 zp.zp_copies, cio->io_allocator, cio, flags)); 3169 } 3170 zio_nowait(cio); 3171 } 3172 3173 /* 3174 * Set pio's pipeline to just wait for zio to finish. 3175 */ 3176 pio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 3177 3178 zio_nowait(zio); 3179 3180 return (pio); 3181 } 3182 3183 /* 3184 * The zio_nop_write stage in the pipeline determines if allocating a 3185 * new bp is necessary. The nopwrite feature can handle writes in 3186 * either syncing or open context (i.e. zil writes) and as a result is 3187 * mutually exclusive with dedup. 3188 * 3189 * By leveraging a cryptographically secure checksum, such as SHA256, we 3190 * can compare the checksums of the new data and the old to determine if 3191 * allocating a new block is required. Note that our requirements for 3192 * cryptographic strength are fairly weak: there can't be any accidental 3193 * hash collisions, but we don't need to be secure against intentional 3194 * (malicious) collisions. To trigger a nopwrite, you have to be able 3195 * to write the file to begin with, and triggering an incorrect (hash 3196 * collision) nopwrite is no worse than simply writing to the file. 3197 * That said, there are no known attacks against the checksum algorithms 3198 * used for nopwrite, assuming that the salt and the checksums 3199 * themselves remain secret. 3200 */ 3201 static zio_t * 3202 zio_nop_write(zio_t *zio) 3203 { 3204 blkptr_t *bp = zio->io_bp; 3205 blkptr_t *bp_orig = &zio->io_bp_orig; 3206 zio_prop_t *zp = &zio->io_prop; 3207 3208 ASSERT(BP_IS_HOLE(bp)); 3209 ASSERT(BP_GET_LEVEL(bp) == 0); 3210 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE)); 3211 ASSERT(zp->zp_nopwrite); 3212 ASSERT(!zp->zp_dedup); 3213 ASSERT(zio->io_bp_override == NULL); 3214 ASSERT(IO_IS_ALLOCATING(zio)); 3215 3216 /* 3217 * Check to see if the original bp and the new bp have matching 3218 * characteristics (i.e. same checksum, compression algorithms, etc). 3219 * If they don't then just continue with the pipeline which will 3220 * allocate a new bp. 3221 */ 3222 if (BP_IS_HOLE(bp_orig) || 3223 !(zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_flags & 3224 ZCHECKSUM_FLAG_NOPWRITE) || 3225 BP_IS_ENCRYPTED(bp) || BP_IS_ENCRYPTED(bp_orig) || 3226 BP_GET_CHECKSUM(bp) != BP_GET_CHECKSUM(bp_orig) || 3227 BP_GET_COMPRESS(bp) != BP_GET_COMPRESS(bp_orig) || 3228 BP_GET_DEDUP(bp) != BP_GET_DEDUP(bp_orig) || 3229 zp->zp_copies != BP_GET_NDVAS(bp_orig)) 3230 return (zio); 3231 3232 /* 3233 * If the checksums match then reset the pipeline so that we 3234 * avoid allocating a new bp and issuing any I/O. 3235 */ 3236 if (ZIO_CHECKSUM_EQUAL(bp->blk_cksum, bp_orig->blk_cksum)) { 3237 ASSERT(zio_checksum_table[zp->zp_checksum].ci_flags & 3238 ZCHECKSUM_FLAG_NOPWRITE); 3239 ASSERT3U(BP_GET_PSIZE(bp), ==, BP_GET_PSIZE(bp_orig)); 3240 ASSERT3U(BP_GET_LSIZE(bp), ==, BP_GET_LSIZE(bp_orig)); 3241 ASSERT(zp->zp_compress != ZIO_COMPRESS_OFF); 3242 ASSERT3U(bp->blk_prop, ==, bp_orig->blk_prop); 3243 3244 /* 3245 * If we're overwriting a block that is currently on an 3246 * indirect vdev, then ignore the nopwrite request and 3247 * allow a new block to be allocated on a concrete vdev. 3248 */ 3249 spa_config_enter(zio->io_spa, SCL_VDEV, FTAG, RW_READER); 3250 for (int d = 0; d < BP_GET_NDVAS(bp_orig); d++) { 3251 vdev_t *tvd = vdev_lookup_top(zio->io_spa, 3252 DVA_GET_VDEV(&bp_orig->blk_dva[d])); 3253 if (tvd->vdev_ops == &vdev_indirect_ops) { 3254 spa_config_exit(zio->io_spa, SCL_VDEV, FTAG); 3255 return (zio); 3256 } 3257 } 3258 spa_config_exit(zio->io_spa, SCL_VDEV, FTAG); 3259 3260 *bp = *bp_orig; 3261 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 3262 zio->io_flags |= ZIO_FLAG_NOPWRITE; 3263 } 3264 3265 return (zio); 3266 } 3267 3268 /* 3269 * ========================================================================== 3270 * Block Reference Table 3271 * ========================================================================== 3272 */ 3273 static zio_t * 3274 zio_brt_free(zio_t *zio) 3275 { 3276 blkptr_t *bp; 3277 3278 bp = zio->io_bp; 3279 3280 if (BP_GET_LEVEL(bp) > 0 || 3281 BP_IS_METADATA(bp) || 3282 !brt_maybe_exists(zio->io_spa, bp)) { 3283 return (zio); 3284 } 3285 3286 if (!brt_entry_decref(zio->io_spa, bp)) { 3287 /* 3288 * This isn't the last reference, so we cannot free 3289 * the data yet. 3290 */ 3291 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 3292 } 3293 3294 return (zio); 3295 } 3296 3297 /* 3298 * ========================================================================== 3299 * Dedup 3300 * ========================================================================== 3301 */ 3302 static void 3303 zio_ddt_child_read_done(zio_t *zio) 3304 { 3305 blkptr_t *bp = zio->io_bp; 3306 ddt_t *ddt; 3307 ddt_entry_t *dde = zio->io_private; 3308 zio_t *pio = zio_unique_parent(zio); 3309 3310 mutex_enter(&pio->io_lock); 3311 ddt = ddt_select(zio->io_spa, bp); 3312 3313 if (zio->io_error == 0) { 3314 ddt_phys_variant_t v = ddt_phys_select(ddt, dde, bp); 3315 /* this phys variant doesn't need repair */ 3316 ddt_phys_clear(dde->dde_phys, v); 3317 } 3318 3319 if (zio->io_error == 0 && dde->dde_io->dde_repair_abd == NULL) 3320 dde->dde_io->dde_repair_abd = zio->io_abd; 3321 else 3322 abd_free(zio->io_abd); 3323 mutex_exit(&pio->io_lock); 3324 } 3325 3326 static zio_t * 3327 zio_ddt_read_start(zio_t *zio) 3328 { 3329 blkptr_t *bp = zio->io_bp; 3330 3331 ASSERT(BP_GET_DEDUP(bp)); 3332 ASSERT(BP_GET_PSIZE(bp) == zio->io_size); 3333 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 3334 3335 if (zio->io_child_error[ZIO_CHILD_DDT]) { 3336 ddt_t *ddt = ddt_select(zio->io_spa, bp); 3337 ddt_entry_t *dde = ddt_repair_start(ddt, bp); 3338 ddt_phys_variant_t v_self = ddt_phys_select(ddt, dde, bp); 3339 ddt_univ_phys_t *ddp = dde->dde_phys; 3340 blkptr_t blk; 3341 3342 ASSERT(zio->io_vsd == NULL); 3343 zio->io_vsd = dde; 3344 3345 if (v_self == DDT_PHYS_NONE) 3346 return (zio); 3347 3348 /* issue I/O for the other copies */ 3349 for (int p = 0; p < DDT_NPHYS(ddt); p++) { 3350 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3351 3352 if (ddt_phys_birth(ddp, v) == 0 || v == v_self) 3353 continue; 3354 3355 ddt_bp_create(ddt->ddt_checksum, &dde->dde_key, 3356 ddp, v, &blk); 3357 zio_nowait(zio_read(zio, zio->io_spa, &blk, 3358 abd_alloc_for_io(zio->io_size, B_TRUE), 3359 zio->io_size, zio_ddt_child_read_done, dde, 3360 zio->io_priority, ZIO_DDT_CHILD_FLAGS(zio) | 3361 ZIO_FLAG_DONT_PROPAGATE, &zio->io_bookmark)); 3362 } 3363 return (zio); 3364 } 3365 3366 zio_nowait(zio_read(zio, zio->io_spa, bp, 3367 zio->io_abd, zio->io_size, NULL, NULL, zio->io_priority, 3368 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark)); 3369 3370 return (zio); 3371 } 3372 3373 static zio_t * 3374 zio_ddt_read_done(zio_t *zio) 3375 { 3376 blkptr_t *bp = zio->io_bp; 3377 3378 if (zio_wait_for_children(zio, ZIO_CHILD_DDT_BIT, ZIO_WAIT_DONE)) { 3379 return (NULL); 3380 } 3381 3382 ASSERT(BP_GET_DEDUP(bp)); 3383 ASSERT(BP_GET_PSIZE(bp) == zio->io_size); 3384 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 3385 3386 if (zio->io_child_error[ZIO_CHILD_DDT]) { 3387 ddt_t *ddt = ddt_select(zio->io_spa, bp); 3388 ddt_entry_t *dde = zio->io_vsd; 3389 if (ddt == NULL) { 3390 ASSERT(spa_load_state(zio->io_spa) != SPA_LOAD_NONE); 3391 return (zio); 3392 } 3393 if (dde == NULL) { 3394 zio->io_stage = ZIO_STAGE_DDT_READ_START >> 1; 3395 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE); 3396 return (NULL); 3397 } 3398 if (dde->dde_io->dde_repair_abd != NULL) { 3399 abd_copy(zio->io_abd, dde->dde_io->dde_repair_abd, 3400 zio->io_size); 3401 zio->io_child_error[ZIO_CHILD_DDT] = 0; 3402 } 3403 ddt_repair_done(ddt, dde); 3404 zio->io_vsd = NULL; 3405 } 3406 3407 ASSERT(zio->io_vsd == NULL); 3408 3409 return (zio); 3410 } 3411 3412 static boolean_t 3413 zio_ddt_collision(zio_t *zio, ddt_t *ddt, ddt_entry_t *dde) 3414 { 3415 spa_t *spa = zio->io_spa; 3416 boolean_t do_raw = !!(zio->io_flags & ZIO_FLAG_RAW); 3417 3418 ASSERT(!(zio->io_bp_override && do_raw)); 3419 3420 /* 3421 * Note: we compare the original data, not the transformed data, 3422 * because when zio->io_bp is an override bp, we will not have 3423 * pushed the I/O transforms. That's an important optimization 3424 * because otherwise we'd compress/encrypt all dmu_sync() data twice. 3425 * However, we should never get a raw, override zio so in these 3426 * cases we can compare the io_abd directly. This is useful because 3427 * it allows us to do dedup verification even if we don't have access 3428 * to the original data (for instance, if the encryption keys aren't 3429 * loaded). 3430 */ 3431 3432 for (int p = 0; p < DDT_NPHYS(ddt); p++) { 3433 if (DDT_PHYS_IS_DITTO(ddt, p)) 3434 continue; 3435 3436 if (dde->dde_io == NULL) 3437 continue; 3438 3439 zio_t *lio = dde->dde_io->dde_lead_zio[p]; 3440 if (lio == NULL) 3441 continue; 3442 3443 if (do_raw) 3444 return (lio->io_size != zio->io_size || 3445 abd_cmp(zio->io_abd, lio->io_abd) != 0); 3446 3447 return (lio->io_orig_size != zio->io_orig_size || 3448 abd_cmp(zio->io_orig_abd, lio->io_orig_abd) != 0); 3449 } 3450 3451 for (int p = 0; p < DDT_NPHYS(ddt); p++) { 3452 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3453 uint64_t phys_birth = ddt_phys_birth(dde->dde_phys, v); 3454 3455 if (phys_birth != 0 && do_raw) { 3456 blkptr_t blk = *zio->io_bp; 3457 uint64_t psize; 3458 abd_t *tmpabd; 3459 int error; 3460 3461 ddt_bp_fill(dde->dde_phys, v, &blk, phys_birth); 3462 psize = BP_GET_PSIZE(&blk); 3463 3464 if (psize != zio->io_size) 3465 return (B_TRUE); 3466 3467 ddt_exit(ddt); 3468 3469 tmpabd = abd_alloc_for_io(psize, B_TRUE); 3470 3471 error = zio_wait(zio_read(NULL, spa, &blk, tmpabd, 3472 psize, NULL, NULL, ZIO_PRIORITY_SYNC_READ, 3473 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | 3474 ZIO_FLAG_RAW, &zio->io_bookmark)); 3475 3476 if (error == 0) { 3477 if (abd_cmp(tmpabd, zio->io_abd) != 0) 3478 error = SET_ERROR(ENOENT); 3479 } 3480 3481 abd_free(tmpabd); 3482 ddt_enter(ddt); 3483 return (error != 0); 3484 } else if (phys_birth != 0) { 3485 arc_buf_t *abuf = NULL; 3486 arc_flags_t aflags = ARC_FLAG_WAIT; 3487 blkptr_t blk = *zio->io_bp; 3488 int error; 3489 3490 ddt_bp_fill(dde->dde_phys, v, &blk, phys_birth); 3491 3492 if (BP_GET_LSIZE(&blk) != zio->io_orig_size) 3493 return (B_TRUE); 3494 3495 ddt_exit(ddt); 3496 3497 error = arc_read(NULL, spa, &blk, 3498 arc_getbuf_func, &abuf, ZIO_PRIORITY_SYNC_READ, 3499 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, 3500 &aflags, &zio->io_bookmark); 3501 3502 if (error == 0) { 3503 if (abd_cmp_buf(zio->io_orig_abd, abuf->b_data, 3504 zio->io_orig_size) != 0) 3505 error = SET_ERROR(ENOENT); 3506 arc_buf_destroy(abuf, &abuf); 3507 } 3508 3509 ddt_enter(ddt); 3510 return (error != 0); 3511 } 3512 } 3513 3514 return (B_FALSE); 3515 } 3516 3517 static void 3518 zio_ddt_child_write_done(zio_t *zio) 3519 { 3520 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp); 3521 ddt_entry_t *dde = zio->io_private; 3522 3523 zio_link_t *zl = NULL; 3524 ASSERT3P(zio_walk_parents(zio, &zl), !=, NULL); 3525 3526 int p = DDT_PHYS_FOR_COPIES(ddt, zio->io_prop.zp_copies); 3527 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3528 ddt_univ_phys_t *ddp = dde->dde_phys; 3529 3530 ddt_enter(ddt); 3531 3532 /* we're the lead, so once we're done there's no one else outstanding */ 3533 if (dde->dde_io->dde_lead_zio[p] == zio) 3534 dde->dde_io->dde_lead_zio[p] = NULL; 3535 3536 ddt_univ_phys_t *orig = &dde->dde_io->dde_orig_phys; 3537 3538 if (zio->io_error != 0) { 3539 /* 3540 * The write failed, so we're about to abort the entire IO 3541 * chain. We need to revert the entry back to what it was at 3542 * the last time it was successfully extended. 3543 */ 3544 ddt_phys_copy(ddp, orig, v); 3545 ddt_phys_clear(orig, v); 3546 3547 ddt_exit(ddt); 3548 return; 3549 } 3550 3551 /* 3552 * We've successfully added new DVAs to the entry. Clear the saved 3553 * state or, if there's still outstanding IO, remember it so we can 3554 * revert to a known good state if that IO fails. 3555 */ 3556 if (dde->dde_io->dde_lead_zio[p] == NULL) 3557 ddt_phys_clear(orig, v); 3558 else 3559 ddt_phys_copy(orig, ddp, v); 3560 3561 /* 3562 * Add references for all dedup writes that were waiting on the 3563 * physical one, skipping any other physical writes that are waiting. 3564 */ 3565 zio_t *pio; 3566 zl = NULL; 3567 while ((pio = zio_walk_parents(zio, &zl)) != NULL) { 3568 if (!(pio->io_flags & ZIO_FLAG_DDT_CHILD)) 3569 ddt_phys_addref(ddp, v); 3570 } 3571 3572 ddt_exit(ddt); 3573 } 3574 3575 static void 3576 zio_ddt_child_write_ready(zio_t *zio) 3577 { 3578 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp); 3579 ddt_entry_t *dde = zio->io_private; 3580 3581 zio_link_t *zl = NULL; 3582 ASSERT3P(zio_walk_parents(zio, &zl), !=, NULL); 3583 3584 int p = DDT_PHYS_FOR_COPIES(ddt, zio->io_prop.zp_copies); 3585 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3586 3587 if (zio->io_error != 0) 3588 return; 3589 3590 ddt_enter(ddt); 3591 3592 ddt_phys_extend(dde->dde_phys, v, zio->io_bp); 3593 3594 zio_t *pio; 3595 zl = NULL; 3596 while ((pio = zio_walk_parents(zio, &zl)) != NULL) { 3597 if (!(pio->io_flags & ZIO_FLAG_DDT_CHILD)) 3598 ddt_bp_fill(dde->dde_phys, v, pio->io_bp, zio->io_txg); 3599 } 3600 3601 ddt_exit(ddt); 3602 } 3603 3604 static zio_t * 3605 zio_ddt_write(zio_t *zio) 3606 { 3607 spa_t *spa = zio->io_spa; 3608 blkptr_t *bp = zio->io_bp; 3609 uint64_t txg = zio->io_txg; 3610 zio_prop_t *zp = &zio->io_prop; 3611 ddt_t *ddt = ddt_select(spa, bp); 3612 ddt_entry_t *dde; 3613 3614 ASSERT(BP_GET_DEDUP(bp)); 3615 ASSERT(BP_GET_CHECKSUM(bp) == zp->zp_checksum); 3616 ASSERT(BP_IS_HOLE(bp) || zio->io_bp_override); 3617 ASSERT(!(zio->io_bp_override && (zio->io_flags & ZIO_FLAG_RAW))); 3618 /* 3619 * Deduplication will not take place for Direct I/O writes. The 3620 * ddt_tree will be emptied in syncing context. Direct I/O writes take 3621 * place in the open-context. Direct I/O write can not attempt to 3622 * modify the ddt_tree while issuing out a write. 3623 */ 3624 ASSERT3B(zio->io_prop.zp_direct_write, ==, B_FALSE); 3625 3626 ddt_enter(ddt); 3627 dde = ddt_lookup(ddt, bp); 3628 if (dde == NULL) { 3629 /* DDT size is over its quota so no new entries */ 3630 zp->zp_dedup = B_FALSE; 3631 BP_SET_DEDUP(bp, B_FALSE); 3632 if (zio->io_bp_override == NULL) 3633 zio->io_pipeline = ZIO_WRITE_PIPELINE; 3634 ddt_exit(ddt); 3635 return (zio); 3636 } 3637 3638 if (zp->zp_dedup_verify && zio_ddt_collision(zio, ddt, dde)) { 3639 /* 3640 * If we're using a weak checksum, upgrade to a strong checksum 3641 * and try again. If we're already using a strong checksum, 3642 * we can't resolve it, so just convert to an ordinary write. 3643 * (And automatically e-mail a paper to Nature?) 3644 */ 3645 if (!(zio_checksum_table[zp->zp_checksum].ci_flags & 3646 ZCHECKSUM_FLAG_DEDUP)) { 3647 zp->zp_checksum = spa_dedup_checksum(spa); 3648 zio_pop_transforms(zio); 3649 zio->io_stage = ZIO_STAGE_OPEN; 3650 BP_ZERO(bp); 3651 } else { 3652 zp->zp_dedup = B_FALSE; 3653 BP_SET_DEDUP(bp, B_FALSE); 3654 } 3655 ASSERT(!BP_GET_DEDUP(bp)); 3656 zio->io_pipeline = ZIO_WRITE_PIPELINE; 3657 ddt_exit(ddt); 3658 return (zio); 3659 } 3660 3661 int p = DDT_PHYS_FOR_COPIES(ddt, zp->zp_copies); 3662 ddt_phys_variant_t v = DDT_PHYS_VARIANT(ddt, p); 3663 ddt_univ_phys_t *ddp = dde->dde_phys; 3664 3665 /* 3666 * In the common cases, at this point we have a regular BP with no 3667 * allocated DVAs, and the corresponding DDT entry for its checksum. 3668 * Our goal is to fill the BP with enough DVAs to satisfy its copies= 3669 * requirement. 3670 * 3671 * One of three things needs to happen to fulfill this: 3672 * 3673 * - if the DDT entry has enough DVAs to satisfy the BP, we just copy 3674 * them out of the entry and return; 3675 * 3676 * - if the DDT entry has no DVAs (ie its brand new), then we have to 3677 * issue the write as normal so that DVAs can be allocated and the 3678 * data land on disk. We then copy the DVAs into the DDT entry on 3679 * return. 3680 * 3681 * - if the DDT entry has some DVAs, but too few, we have to issue the 3682 * write, adjusted to have allocate fewer copies. When it returns, we 3683 * add the new DVAs to the DDT entry, and update the BP to have the 3684 * full amount it originally requested. 3685 * 3686 * In all cases, if there's already a writing IO in flight, we need to 3687 * defer the action until after the write is done. If our action is to 3688 * write, we need to adjust our request for additional DVAs to match 3689 * what will be in the DDT entry after it completes. In this way every 3690 * IO can be guaranteed to recieve enough DVAs simply by joining the 3691 * end of the chain and letting the sequence play out. 3692 */ 3693 3694 /* 3695 * Number of DVAs in the DDT entry. If the BP is encrypted we ignore 3696 * the third one as normal. 3697 */ 3698 int have_dvas = ddt_phys_dva_count(ddp, v, BP_IS_ENCRYPTED(bp)); 3699 IMPLY(have_dvas == 0, ddt_phys_birth(ddp, v) == 0); 3700 3701 /* Number of DVAs requested bya the IO. */ 3702 uint8_t need_dvas = zp->zp_copies; 3703 3704 /* 3705 * What we do next depends on whether or not there's IO outstanding that 3706 * will update this entry. 3707 */ 3708 if (dde->dde_io == NULL || dde->dde_io->dde_lead_zio[p] == NULL) { 3709 /* 3710 * No IO outstanding, so we only need to worry about ourselves. 3711 */ 3712 3713 /* 3714 * Override BPs bring their own DVAs and their own problems. 3715 */ 3716 if (zio->io_bp_override) { 3717 /* 3718 * For a brand-new entry, all the work has been done 3719 * for us, and we can just fill it out from the provided 3720 * block and leave. 3721 */ 3722 if (have_dvas == 0) { 3723 ASSERT(BP_GET_LOGICAL_BIRTH(bp) == txg); 3724 ASSERT(BP_EQUAL(bp, zio->io_bp_override)); 3725 ddt_phys_extend(ddp, v, bp); 3726 ddt_phys_addref(ddp, v); 3727 ddt_exit(ddt); 3728 return (zio); 3729 } 3730 3731 /* 3732 * If we already have this entry, then we want to treat 3733 * it like a regular write. To do this we just wipe 3734 * them out and proceed like a regular write. 3735 * 3736 * Even if there are some DVAs in the entry, we still 3737 * have to clear them out. We can't use them to fill 3738 * out the dedup entry, as they are all referenced 3739 * together by a bp already on disk, and will be freed 3740 * as a group. 3741 */ 3742 BP_ZERO_DVAS(bp); 3743 BP_SET_BIRTH(bp, 0, 0); 3744 } 3745 3746 /* 3747 * If there are enough DVAs in the entry to service our request, 3748 * then we can just use them as-is. 3749 */ 3750 if (have_dvas >= need_dvas) { 3751 ddt_bp_fill(ddp, v, bp, txg); 3752 ddt_phys_addref(ddp, v); 3753 ddt_exit(ddt); 3754 return (zio); 3755 } 3756 3757 /* 3758 * Otherwise, we have to issue IO to fill the entry up to the 3759 * amount we need. 3760 */ 3761 need_dvas -= have_dvas; 3762 } else { 3763 /* 3764 * There's a write in-flight. If there's already enough DVAs on 3765 * the entry, then either there were already enough to start 3766 * with, or the in-flight IO is between READY and DONE, and so 3767 * has extended the entry with new DVAs. Either way, we don't 3768 * need to do anything, we can just slot in behind it. 3769 */ 3770 3771 if (zio->io_bp_override) { 3772 /* 3773 * If there's a write out, then we're soon going to 3774 * have our own copies of this block, so clear out the 3775 * override block and treat it as a regular dedup 3776 * write. See comment above. 3777 */ 3778 BP_ZERO_DVAS(bp); 3779 BP_SET_BIRTH(bp, 0, 0); 3780 } 3781 3782 if (have_dvas >= need_dvas) { 3783 /* 3784 * A minor point: there might already be enough 3785 * committed DVAs in the entry to service our request, 3786 * but we don't know which are completed and which are 3787 * allocated but not yet written. In this case, should 3788 * the IO for the new DVAs fail, we will be on the end 3789 * of the IO chain and will also recieve an error, even 3790 * though our request could have been serviced. 3791 * 3792 * This is an extremely rare case, as it requires the 3793 * original block to be copied with a request for a 3794 * larger number of DVAs, then copied again requesting 3795 * the same (or already fulfilled) number of DVAs while 3796 * the first request is active, and then that first 3797 * request errors. In return, the logic required to 3798 * catch and handle it is complex. For now, I'm just 3799 * not going to bother with it. 3800 */ 3801 3802 /* 3803 * We always fill the bp here as we may have arrived 3804 * after the in-flight write has passed READY, and so 3805 * missed out. 3806 */ 3807 ddt_bp_fill(ddp, v, bp, txg); 3808 zio_add_child(zio, dde->dde_io->dde_lead_zio[p]); 3809 ddt_exit(ddt); 3810 return (zio); 3811 } 3812 3813 /* 3814 * There's not enough in the entry yet, so we need to look at 3815 * the write in-flight and see how many DVAs it will have once 3816 * it completes. 3817 * 3818 * The in-flight write has potentially had its copies request 3819 * reduced (if we're filling out an existing entry), so we need 3820 * to reach in and get the original write to find out what it is 3821 * expecting. 3822 * 3823 * Note that the parent of the lead zio will always have the 3824 * highest zp_copies of any zio in the chain, because ones that 3825 * can be serviced without additional IO are always added to 3826 * the back of the chain. 3827 */ 3828 zio_link_t *zl = NULL; 3829 zio_t *pio = 3830 zio_walk_parents(dde->dde_io->dde_lead_zio[p], &zl); 3831 ASSERT(pio); 3832 uint8_t parent_dvas = pio->io_prop.zp_copies; 3833 3834 if (parent_dvas >= need_dvas) { 3835 zio_add_child(zio, dde->dde_io->dde_lead_zio[p]); 3836 ddt_exit(ddt); 3837 return (zio); 3838 } 3839 3840 /* 3841 * Still not enough, so we will need to issue to get the 3842 * shortfall. 3843 */ 3844 need_dvas -= parent_dvas; 3845 } 3846 3847 /* 3848 * We need to write. We will create a new write with the copies 3849 * property adjusted to match the number of DVAs we need to need to 3850 * grow the DDT entry by to satisfy the request. 3851 */ 3852 zio_prop_t czp = *zp; 3853 czp.zp_copies = need_dvas; 3854 zio_t *cio = zio_write(zio, spa, txg, bp, zio->io_orig_abd, 3855 zio->io_orig_size, zio->io_orig_size, &czp, 3856 zio_ddt_child_write_ready, NULL, 3857 zio_ddt_child_write_done, dde, zio->io_priority, 3858 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark); 3859 3860 zio_push_transform(cio, zio->io_abd, zio->io_size, 0, NULL); 3861 3862 /* 3863 * We are the new lead zio, because our parent has the highest 3864 * zp_copies that has been requested for this entry so far. 3865 */ 3866 ddt_alloc_entry_io(dde); 3867 if (dde->dde_io->dde_lead_zio[p] == NULL) { 3868 /* 3869 * First time out, take a copy of the stable entry to revert 3870 * to if there's an error (see zio_ddt_child_write_done()) 3871 */ 3872 ddt_phys_copy(&dde->dde_io->dde_orig_phys, dde->dde_phys, v); 3873 } else { 3874 /* 3875 * Make the existing chain our child, because it cannot 3876 * complete until we have. 3877 */ 3878 zio_add_child(cio, dde->dde_io->dde_lead_zio[p]); 3879 } 3880 dde->dde_io->dde_lead_zio[p] = cio; 3881 3882 ddt_exit(ddt); 3883 3884 zio_nowait(cio); 3885 3886 return (zio); 3887 } 3888 3889 static ddt_entry_t *freedde; /* for debugging */ 3890 3891 static zio_t * 3892 zio_ddt_free(zio_t *zio) 3893 { 3894 spa_t *spa = zio->io_spa; 3895 blkptr_t *bp = zio->io_bp; 3896 ddt_t *ddt = ddt_select(spa, bp); 3897 ddt_entry_t *dde = NULL; 3898 3899 ASSERT(BP_GET_DEDUP(bp)); 3900 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 3901 3902 ddt_enter(ddt); 3903 freedde = dde = ddt_lookup(ddt, bp); 3904 if (dde) { 3905 ddt_phys_variant_t v = ddt_phys_select(ddt, dde, bp); 3906 if (v != DDT_PHYS_NONE) 3907 ddt_phys_decref(dde->dde_phys, v); 3908 } 3909 ddt_exit(ddt); 3910 3911 /* 3912 * When no entry was found, it must have been pruned, 3913 * so we can free it now instead of decrementing the 3914 * refcount in the DDT. 3915 */ 3916 if (!dde) { 3917 BP_SET_DEDUP(bp, 0); 3918 zio->io_pipeline |= ZIO_STAGE_DVA_FREE; 3919 } 3920 3921 return (zio); 3922 } 3923 3924 /* 3925 * ========================================================================== 3926 * Allocate and free blocks 3927 * ========================================================================== 3928 */ 3929 3930 static zio_t * 3931 zio_io_to_allocate(spa_t *spa, int allocator) 3932 { 3933 zio_t *zio; 3934 3935 ASSERT(MUTEX_HELD(&spa->spa_allocs[allocator].spaa_lock)); 3936 3937 zio = avl_first(&spa->spa_allocs[allocator].spaa_tree); 3938 if (zio == NULL) 3939 return (NULL); 3940 3941 ASSERT(IO_IS_ALLOCATING(zio)); 3942 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 3943 3944 /* 3945 * Try to place a reservation for this zio. If we're unable to 3946 * reserve then we throttle. 3947 */ 3948 ASSERT3U(zio->io_allocator, ==, allocator); 3949 if (!metaslab_class_throttle_reserve(zio->io_metaslab_class, 3950 zio->io_prop.zp_copies, allocator, zio, 0)) { 3951 return (NULL); 3952 } 3953 3954 avl_remove(&spa->spa_allocs[allocator].spaa_tree, zio); 3955 ASSERT3U(zio->io_stage, <, ZIO_STAGE_DVA_ALLOCATE); 3956 3957 return (zio); 3958 } 3959 3960 static zio_t * 3961 zio_dva_throttle(zio_t *zio) 3962 { 3963 spa_t *spa = zio->io_spa; 3964 zio_t *nio; 3965 metaslab_class_t *mc; 3966 3967 /* locate an appropriate allocation class */ 3968 mc = spa_preferred_class(spa, zio); 3969 3970 if (zio->io_priority == ZIO_PRIORITY_SYNC_WRITE || 3971 !mc->mc_alloc_throttle_enabled || 3972 zio->io_child_type == ZIO_CHILD_GANG || 3973 zio->io_flags & ZIO_FLAG_NODATA) { 3974 return (zio); 3975 } 3976 3977 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 3978 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 3979 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 3980 ASSERT3U(zio->io_queued_timestamp, >, 0); 3981 ASSERT(zio->io_stage == ZIO_STAGE_DVA_THROTTLE); 3982 3983 int allocator = zio->io_allocator; 3984 zio->io_metaslab_class = mc; 3985 mutex_enter(&spa->spa_allocs[allocator].spaa_lock); 3986 avl_add(&spa->spa_allocs[allocator].spaa_tree, zio); 3987 nio = zio_io_to_allocate(spa, allocator); 3988 mutex_exit(&spa->spa_allocs[allocator].spaa_lock); 3989 return (nio); 3990 } 3991 3992 static void 3993 zio_allocate_dispatch(spa_t *spa, int allocator) 3994 { 3995 zio_t *zio; 3996 3997 mutex_enter(&spa->spa_allocs[allocator].spaa_lock); 3998 zio = zio_io_to_allocate(spa, allocator); 3999 mutex_exit(&spa->spa_allocs[allocator].spaa_lock); 4000 if (zio == NULL) 4001 return; 4002 4003 ASSERT3U(zio->io_stage, ==, ZIO_STAGE_DVA_THROTTLE); 4004 ASSERT0(zio->io_error); 4005 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_TRUE); 4006 } 4007 4008 static zio_t * 4009 zio_dva_allocate(zio_t *zio) 4010 { 4011 spa_t *spa = zio->io_spa; 4012 metaslab_class_t *mc; 4013 blkptr_t *bp = zio->io_bp; 4014 int error; 4015 int flags = 0; 4016 4017 if (zio->io_gang_leader == NULL) { 4018 ASSERT(zio->io_child_type > ZIO_CHILD_GANG); 4019 zio->io_gang_leader = zio; 4020 } 4021 4022 ASSERT(BP_IS_HOLE(bp)); 4023 ASSERT0(BP_GET_NDVAS(bp)); 4024 ASSERT3U(zio->io_prop.zp_copies, >, 0); 4025 ASSERT3U(zio->io_prop.zp_copies, <=, spa_max_replication(spa)); 4026 ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp)); 4027 4028 if (zio->io_flags & ZIO_FLAG_NODATA) 4029 flags |= METASLAB_DONT_THROTTLE; 4030 if (zio->io_flags & ZIO_FLAG_GANG_CHILD) 4031 flags |= METASLAB_GANG_CHILD; 4032 if (zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE) 4033 flags |= METASLAB_ASYNC_ALLOC; 4034 4035 /* 4036 * if not already chosen, locate an appropriate allocation class 4037 */ 4038 mc = zio->io_metaslab_class; 4039 if (mc == NULL) { 4040 mc = spa_preferred_class(spa, zio); 4041 zio->io_metaslab_class = mc; 4042 } 4043 4044 /* 4045 * Try allocating the block in the usual metaslab class. 4046 * If that's full, allocate it in the normal class. 4047 * If that's full, allocate as a gang block, 4048 * and if all are full, the allocation fails (which shouldn't happen). 4049 * 4050 * Note that we do not fall back on embedded slog (ZIL) space, to 4051 * preserve unfragmented slog space, which is critical for decent 4052 * sync write performance. If a log allocation fails, we will fall 4053 * back to spa_sync() which is abysmal for performance. 4054 */ 4055 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 4056 error = metaslab_alloc(spa, mc, zio->io_size, bp, 4057 zio->io_prop.zp_copies, zio->io_txg, NULL, flags, 4058 &zio->io_alloc_list, zio, zio->io_allocator); 4059 4060 /* 4061 * Fallback to normal class when an alloc class is full 4062 */ 4063 if (error == ENOSPC && mc != spa_normal_class(spa)) { 4064 /* 4065 * When the dedup or special class is spilling into the normal 4066 * class, there can still be significant space available due 4067 * to deferred frees that are in-flight. We track the txg when 4068 * this occurred and back off adding new DDT entries for a few 4069 * txgs to allow the free blocks to be processed. 4070 */ 4071 if ((mc == spa_dedup_class(spa) || (spa_special_has_ddt(spa) && 4072 mc == spa_special_class(spa))) && 4073 spa->spa_dedup_class_full_txg != zio->io_txg) { 4074 spa->spa_dedup_class_full_txg = zio->io_txg; 4075 zfs_dbgmsg("%s[%d]: %s class spilling, req size %d, " 4076 "%llu allocated of %llu", 4077 spa_name(spa), (int)zio->io_txg, 4078 mc == spa_dedup_class(spa) ? "dedup" : "special", 4079 (int)zio->io_size, 4080 (u_longlong_t)metaslab_class_get_alloc(mc), 4081 (u_longlong_t)metaslab_class_get_space(mc)); 4082 } 4083 4084 /* 4085 * If throttling, transfer reservation over to normal class. 4086 * The io_allocator slot can remain the same even though we 4087 * are switching classes. 4088 */ 4089 if (mc->mc_alloc_throttle_enabled && 4090 (zio->io_flags & ZIO_FLAG_IO_ALLOCATING)) { 4091 metaslab_class_throttle_unreserve(mc, 4092 zio->io_prop.zp_copies, zio->io_allocator, zio); 4093 zio->io_flags &= ~ZIO_FLAG_IO_ALLOCATING; 4094 4095 VERIFY(metaslab_class_throttle_reserve( 4096 spa_normal_class(spa), 4097 zio->io_prop.zp_copies, zio->io_allocator, zio, 4098 flags | METASLAB_MUST_RESERVE)); 4099 } 4100 zio->io_metaslab_class = mc = spa_normal_class(spa); 4101 if (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC) { 4102 zfs_dbgmsg("%s: metaslab allocation failure, " 4103 "trying normal class: zio %px, size %llu, error %d", 4104 spa_name(spa), zio, (u_longlong_t)zio->io_size, 4105 error); 4106 } 4107 4108 error = metaslab_alloc(spa, mc, zio->io_size, bp, 4109 zio->io_prop.zp_copies, zio->io_txg, NULL, flags, 4110 &zio->io_alloc_list, zio, zio->io_allocator); 4111 } 4112 4113 if (error == ENOSPC && zio->io_size > SPA_MINBLOCKSIZE) { 4114 if (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC) { 4115 zfs_dbgmsg("%s: metaslab allocation failure, " 4116 "trying ganging: zio %px, size %llu, error %d", 4117 spa_name(spa), zio, (u_longlong_t)zio->io_size, 4118 error); 4119 } 4120 return (zio_write_gang_block(zio, mc)); 4121 } 4122 if (error != 0) { 4123 if (error != ENOSPC || 4124 (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC)) { 4125 zfs_dbgmsg("%s: metaslab allocation failure: zio %px, " 4126 "size %llu, error %d", 4127 spa_name(spa), zio, (u_longlong_t)zio->io_size, 4128 error); 4129 } 4130 zio->io_error = error; 4131 } 4132 4133 return (zio); 4134 } 4135 4136 static zio_t * 4137 zio_dva_free(zio_t *zio) 4138 { 4139 metaslab_free(zio->io_spa, zio->io_bp, zio->io_txg, B_FALSE); 4140 4141 return (zio); 4142 } 4143 4144 static zio_t * 4145 zio_dva_claim(zio_t *zio) 4146 { 4147 int error; 4148 4149 error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg); 4150 if (error) 4151 zio->io_error = error; 4152 4153 return (zio); 4154 } 4155 4156 /* 4157 * Undo an allocation. This is used by zio_done() when an I/O fails 4158 * and we want to give back the block we just allocated. 4159 * This handles both normal blocks and gang blocks. 4160 */ 4161 static void 4162 zio_dva_unallocate(zio_t *zio, zio_gang_node_t *gn, blkptr_t *bp) 4163 { 4164 ASSERT(BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg || BP_IS_HOLE(bp)); 4165 ASSERT(zio->io_bp_override == NULL); 4166 4167 if (!BP_IS_HOLE(bp)) { 4168 metaslab_free(zio->io_spa, bp, BP_GET_LOGICAL_BIRTH(bp), 4169 B_TRUE); 4170 } 4171 4172 if (gn != NULL) { 4173 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) { 4174 zio_dva_unallocate(zio, gn->gn_child[g], 4175 &gn->gn_gbh->zg_blkptr[g]); 4176 } 4177 } 4178 } 4179 4180 /* 4181 * Try to allocate an intent log block. Return 0 on success, errno on failure. 4182 */ 4183 int 4184 zio_alloc_zil(spa_t *spa, objset_t *os, uint64_t txg, blkptr_t *new_bp, 4185 uint64_t size, boolean_t *slog) 4186 { 4187 int error = 1; 4188 zio_alloc_list_t io_alloc_list; 4189 4190 ASSERT(txg > spa_syncing_txg(spa)); 4191 4192 metaslab_trace_init(&io_alloc_list); 4193 4194 /* 4195 * Block pointer fields are useful to metaslabs for stats and debugging. 4196 * Fill in the obvious ones before calling into metaslab_alloc(). 4197 */ 4198 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG); 4199 BP_SET_PSIZE(new_bp, size); 4200 BP_SET_LEVEL(new_bp, 0); 4201 4202 /* 4203 * When allocating a zil block, we don't have information about 4204 * the final destination of the block except the objset it's part 4205 * of, so we just hash the objset ID to pick the allocator to get 4206 * some parallelism. 4207 */ 4208 int flags = METASLAB_ZIL; 4209 int allocator = (uint_t)cityhash1(os->os_dsl_dataset->ds_object) 4210 % spa->spa_alloc_count; 4211 error = metaslab_alloc(spa, spa_log_class(spa), size, new_bp, 1, 4212 txg, NULL, flags, &io_alloc_list, NULL, allocator); 4213 *slog = (error == 0); 4214 if (error != 0) { 4215 error = metaslab_alloc(spa, spa_embedded_log_class(spa), size, 4216 new_bp, 1, txg, NULL, flags, 4217 &io_alloc_list, NULL, allocator); 4218 } 4219 if (error != 0) { 4220 error = metaslab_alloc(spa, spa_normal_class(spa), size, 4221 new_bp, 1, txg, NULL, flags, 4222 &io_alloc_list, NULL, allocator); 4223 } 4224 metaslab_trace_fini(&io_alloc_list); 4225 4226 if (error == 0) { 4227 BP_SET_LSIZE(new_bp, size); 4228 BP_SET_PSIZE(new_bp, size); 4229 BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF); 4230 BP_SET_CHECKSUM(new_bp, 4231 spa_version(spa) >= SPA_VERSION_SLIM_ZIL 4232 ? ZIO_CHECKSUM_ZILOG2 : ZIO_CHECKSUM_ZILOG); 4233 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG); 4234 BP_SET_LEVEL(new_bp, 0); 4235 BP_SET_DEDUP(new_bp, 0); 4236 BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER); 4237 4238 /* 4239 * encrypted blocks will require an IV and salt. We generate 4240 * these now since we will not be rewriting the bp at 4241 * rewrite time. 4242 */ 4243 if (os->os_encrypted) { 4244 uint8_t iv[ZIO_DATA_IV_LEN]; 4245 uint8_t salt[ZIO_DATA_SALT_LEN]; 4246 4247 BP_SET_CRYPT(new_bp, B_TRUE); 4248 VERIFY0(spa_crypt_get_salt(spa, 4249 dmu_objset_id(os), salt)); 4250 VERIFY0(zio_crypt_generate_iv(iv)); 4251 4252 zio_crypt_encode_params_bp(new_bp, salt, iv); 4253 } 4254 } else { 4255 zfs_dbgmsg("%s: zil block allocation failure: " 4256 "size %llu, error %d", spa_name(spa), (u_longlong_t)size, 4257 error); 4258 } 4259 4260 return (error); 4261 } 4262 4263 /* 4264 * ========================================================================== 4265 * Read and write to physical devices 4266 * ========================================================================== 4267 */ 4268 4269 /* 4270 * Issue an I/O to the underlying vdev. Typically the issue pipeline 4271 * stops after this stage and will resume upon I/O completion. 4272 * However, there are instances where the vdev layer may need to 4273 * continue the pipeline when an I/O was not issued. Since the I/O 4274 * that was sent to the vdev layer might be different than the one 4275 * currently active in the pipeline (see vdev_queue_io()), we explicitly 4276 * force the underlying vdev layers to call either zio_execute() or 4277 * zio_interrupt() to ensure that the pipeline continues with the correct I/O. 4278 */ 4279 static zio_t * 4280 zio_vdev_io_start(zio_t *zio) 4281 { 4282 vdev_t *vd = zio->io_vd; 4283 uint64_t align; 4284 spa_t *spa = zio->io_spa; 4285 4286 zio->io_delay = 0; 4287 4288 ASSERT(zio->io_error == 0); 4289 ASSERT(zio->io_child_error[ZIO_CHILD_VDEV] == 0); 4290 4291 if (vd == NULL) { 4292 if (!(zio->io_flags & ZIO_FLAG_CONFIG_WRITER)) 4293 spa_config_enter(spa, SCL_ZIO, zio, RW_READER); 4294 4295 /* 4296 * The mirror_ops handle multiple DVAs in a single BP. 4297 */ 4298 vdev_mirror_ops.vdev_op_io_start(zio); 4299 return (NULL); 4300 } 4301 4302 ASSERT3P(zio->io_logical, !=, zio); 4303 if (zio->io_type == ZIO_TYPE_WRITE) { 4304 ASSERT(spa->spa_trust_config); 4305 4306 /* 4307 * Note: the code can handle other kinds of writes, 4308 * but we don't expect them. 4309 */ 4310 if (zio->io_vd->vdev_noalloc) { 4311 ASSERT(zio->io_flags & 4312 (ZIO_FLAG_PHYSICAL | ZIO_FLAG_SELF_HEAL | 4313 ZIO_FLAG_RESILVER | ZIO_FLAG_INDUCE_DAMAGE)); 4314 } 4315 } 4316 4317 align = 1ULL << vd->vdev_top->vdev_ashift; 4318 4319 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL) && 4320 P2PHASE(zio->io_size, align) != 0) { 4321 /* Transform logical writes to be a full physical block size. */ 4322 uint64_t asize = P2ROUNDUP(zio->io_size, align); 4323 abd_t *abuf = abd_alloc_sametype(zio->io_abd, asize); 4324 ASSERT(vd == vd->vdev_top); 4325 if (zio->io_type == ZIO_TYPE_WRITE) { 4326 abd_copy(abuf, zio->io_abd, zio->io_size); 4327 abd_zero_off(abuf, zio->io_size, asize - zio->io_size); 4328 } 4329 zio_push_transform(zio, abuf, asize, asize, zio_subblock); 4330 } 4331 4332 /* 4333 * If this is not a physical io, make sure that it is properly aligned 4334 * before proceeding. 4335 */ 4336 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL)) { 4337 ASSERT0(P2PHASE(zio->io_offset, align)); 4338 ASSERT0(P2PHASE(zio->io_size, align)); 4339 } else { 4340 /* 4341 * For physical writes, we allow 512b aligned writes and assume 4342 * the device will perform a read-modify-write as necessary. 4343 */ 4344 ASSERT0(P2PHASE(zio->io_offset, SPA_MINBLOCKSIZE)); 4345 ASSERT0(P2PHASE(zio->io_size, SPA_MINBLOCKSIZE)); 4346 } 4347 4348 VERIFY(zio->io_type != ZIO_TYPE_WRITE || spa_writeable(spa)); 4349 4350 /* 4351 * If this is a repair I/O, and there's no self-healing involved -- 4352 * that is, we're just resilvering what we expect to resilver -- 4353 * then don't do the I/O unless zio's txg is actually in vd's DTL. 4354 * This prevents spurious resilvering. 4355 * 4356 * There are a few ways that we can end up creating these spurious 4357 * resilver i/os: 4358 * 4359 * 1. A resilver i/o will be issued if any DVA in the BP has a 4360 * dirty DTL. The mirror code will issue resilver writes to 4361 * each DVA, including the one(s) that are not on vdevs with dirty 4362 * DTLs. 4363 * 4364 * 2. With nested replication, which happens when we have a 4365 * "replacing" or "spare" vdev that's a child of a mirror or raidz. 4366 * For example, given mirror(replacing(A+B), C), it's likely that 4367 * only A is out of date (it's the new device). In this case, we'll 4368 * read from C, then use the data to resilver A+B -- but we don't 4369 * actually want to resilver B, just A. The top-level mirror has no 4370 * way to know this, so instead we just discard unnecessary repairs 4371 * as we work our way down the vdev tree. 4372 * 4373 * 3. ZTEST also creates mirrors of mirrors, mirrors of raidz, etc. 4374 * The same logic applies to any form of nested replication: ditto 4375 * + mirror, RAID-Z + replacing, etc. 4376 * 4377 * However, indirect vdevs point off to other vdevs which may have 4378 * DTL's, so we never bypass them. The child i/os on concrete vdevs 4379 * will be properly bypassed instead. 4380 * 4381 * Leaf DTL_PARTIAL can be empty when a legitimate write comes from 4382 * a dRAID spare vdev. For example, when a dRAID spare is first 4383 * used, its spare blocks need to be written to but the leaf vdev's 4384 * of such blocks can have empty DTL_PARTIAL. 4385 * 4386 * There seemed no clean way to allow such writes while bypassing 4387 * spurious ones. At this point, just avoid all bypassing for dRAID 4388 * for correctness. 4389 */ 4390 if ((zio->io_flags & ZIO_FLAG_IO_REPAIR) && 4391 !(zio->io_flags & ZIO_FLAG_SELF_HEAL) && 4392 zio->io_txg != 0 && /* not a delegated i/o */ 4393 vd->vdev_ops != &vdev_indirect_ops && 4394 vd->vdev_top->vdev_ops != &vdev_draid_ops && 4395 !vdev_dtl_contains(vd, DTL_PARTIAL, zio->io_txg, 1)) { 4396 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 4397 zio_vdev_io_bypass(zio); 4398 return (zio); 4399 } 4400 4401 /* 4402 * Select the next best leaf I/O to process. Distributed spares are 4403 * excluded since they dispatch the I/O directly to a leaf vdev after 4404 * applying the dRAID mapping. 4405 */ 4406 if (vd->vdev_ops->vdev_op_leaf && 4407 vd->vdev_ops != &vdev_draid_spare_ops && 4408 (zio->io_type == ZIO_TYPE_READ || 4409 zio->io_type == ZIO_TYPE_WRITE || 4410 zio->io_type == ZIO_TYPE_TRIM)) { 4411 4412 if (zio_handle_device_injection(vd, zio, ENOSYS) != 0) { 4413 /* 4414 * "no-op" injections return success, but do no actual 4415 * work. Just skip the remaining vdev stages. 4416 */ 4417 zio_vdev_io_bypass(zio); 4418 zio_interrupt(zio); 4419 return (NULL); 4420 } 4421 4422 if ((zio = vdev_queue_io(zio)) == NULL) 4423 return (NULL); 4424 4425 if (!vdev_accessible(vd, zio)) { 4426 zio->io_error = SET_ERROR(ENXIO); 4427 zio_interrupt(zio); 4428 return (NULL); 4429 } 4430 zio->io_delay = gethrtime(); 4431 } 4432 4433 vd->vdev_ops->vdev_op_io_start(zio); 4434 return (NULL); 4435 } 4436 4437 static zio_t * 4438 zio_vdev_io_done(zio_t *zio) 4439 { 4440 vdev_t *vd = zio->io_vd; 4441 vdev_ops_t *ops = vd ? vd->vdev_ops : &vdev_mirror_ops; 4442 boolean_t unexpected_error = B_FALSE; 4443 4444 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV_BIT, ZIO_WAIT_DONE)) { 4445 return (NULL); 4446 } 4447 4448 ASSERT(zio->io_type == ZIO_TYPE_READ || 4449 zio->io_type == ZIO_TYPE_WRITE || 4450 zio->io_type == ZIO_TYPE_FLUSH || 4451 zio->io_type == ZIO_TYPE_TRIM); 4452 4453 if (zio->io_delay) 4454 zio->io_delay = gethrtime() - zio->io_delay; 4455 4456 if (vd != NULL && vd->vdev_ops->vdev_op_leaf && 4457 vd->vdev_ops != &vdev_draid_spare_ops) { 4458 if (zio->io_type != ZIO_TYPE_FLUSH) 4459 vdev_queue_io_done(zio); 4460 4461 if (zio_injection_enabled && zio->io_error == 0) 4462 zio->io_error = zio_handle_device_injections(vd, zio, 4463 EIO, EILSEQ); 4464 4465 if (zio_injection_enabled && zio->io_error == 0) 4466 zio->io_error = zio_handle_label_injection(zio, EIO); 4467 4468 if (zio->io_error && zio->io_type != ZIO_TYPE_FLUSH && 4469 zio->io_type != ZIO_TYPE_TRIM) { 4470 if (!vdev_accessible(vd, zio)) { 4471 zio->io_error = SET_ERROR(ENXIO); 4472 } else { 4473 unexpected_error = B_TRUE; 4474 } 4475 } 4476 } 4477 4478 ops->vdev_op_io_done(zio); 4479 4480 if (unexpected_error && vd->vdev_remove_wanted == B_FALSE) 4481 VERIFY(vdev_probe(vd, zio) == NULL); 4482 4483 return (zio); 4484 } 4485 4486 /* 4487 * This function is used to change the priority of an existing zio that is 4488 * currently in-flight. This is used by the arc to upgrade priority in the 4489 * event that a demand read is made for a block that is currently queued 4490 * as a scrub or async read IO. Otherwise, the high priority read request 4491 * would end up having to wait for the lower priority IO. 4492 */ 4493 void 4494 zio_change_priority(zio_t *pio, zio_priority_t priority) 4495 { 4496 zio_t *cio, *cio_next; 4497 zio_link_t *zl = NULL; 4498 4499 ASSERT3U(priority, <, ZIO_PRIORITY_NUM_QUEUEABLE); 4500 4501 if (pio->io_vd != NULL && pio->io_vd->vdev_ops->vdev_op_leaf) { 4502 vdev_queue_change_io_priority(pio, priority); 4503 } else { 4504 pio->io_priority = priority; 4505 } 4506 4507 mutex_enter(&pio->io_lock); 4508 for (cio = zio_walk_children(pio, &zl); cio != NULL; cio = cio_next) { 4509 cio_next = zio_walk_children(pio, &zl); 4510 zio_change_priority(cio, priority); 4511 } 4512 mutex_exit(&pio->io_lock); 4513 } 4514 4515 /* 4516 * For non-raidz ZIOs, we can just copy aside the bad data read from the 4517 * disk, and use that to finish the checksum ereport later. 4518 */ 4519 static void 4520 zio_vsd_default_cksum_finish(zio_cksum_report_t *zcr, 4521 const abd_t *good_buf) 4522 { 4523 /* no processing needed */ 4524 zfs_ereport_finish_checksum(zcr, good_buf, zcr->zcr_cbdata, B_FALSE); 4525 } 4526 4527 void 4528 zio_vsd_default_cksum_report(zio_t *zio, zio_cksum_report_t *zcr) 4529 { 4530 void *abd = abd_alloc_sametype(zio->io_abd, zio->io_size); 4531 4532 abd_copy(abd, zio->io_abd, zio->io_size); 4533 4534 zcr->zcr_cbinfo = zio->io_size; 4535 zcr->zcr_cbdata = abd; 4536 zcr->zcr_finish = zio_vsd_default_cksum_finish; 4537 zcr->zcr_free = zio_abd_free; 4538 } 4539 4540 static zio_t * 4541 zio_vdev_io_assess(zio_t *zio) 4542 { 4543 vdev_t *vd = zio->io_vd; 4544 4545 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV_BIT, ZIO_WAIT_DONE)) { 4546 return (NULL); 4547 } 4548 4549 if (vd == NULL && !(zio->io_flags & ZIO_FLAG_CONFIG_WRITER)) 4550 spa_config_exit(zio->io_spa, SCL_ZIO, zio); 4551 4552 if (zio->io_vsd != NULL) { 4553 zio->io_vsd_ops->vsd_free(zio); 4554 zio->io_vsd = NULL; 4555 } 4556 4557 /* 4558 * If a Direct I/O write checksum verify error has occurred then this 4559 * I/O should not attempt to be issued again. Instead the EIO will 4560 * be returned. 4561 */ 4562 if (zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR) { 4563 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_LOGICAL); 4564 ASSERT3U(zio->io_error, ==, EIO); 4565 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 4566 return (zio); 4567 } 4568 4569 4570 if (zio_injection_enabled && zio->io_error == 0) 4571 zio->io_error = zio_handle_fault_injection(zio, EIO); 4572 4573 /* 4574 * If the I/O failed, determine whether we should attempt to retry it. 4575 * 4576 * On retry, we cut in line in the issue queue, since we don't want 4577 * compression/checksumming/etc. work to prevent our (cheap) IO reissue. 4578 */ 4579 if (zio->io_error && vd == NULL && 4580 !(zio->io_flags & (ZIO_FLAG_DONT_RETRY | ZIO_FLAG_IO_RETRY))) { 4581 ASSERT(!(zio->io_flags & ZIO_FLAG_DONT_QUEUE)); /* not a leaf */ 4582 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_BYPASS)); /* not a leaf */ 4583 zio->io_error = 0; 4584 zio->io_flags |= ZIO_FLAG_IO_RETRY | ZIO_FLAG_DONT_AGGREGATE; 4585 zio->io_stage = ZIO_STAGE_VDEV_IO_START >> 1; 4586 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, 4587 zio_requeue_io_start_cut_in_line); 4588 return (NULL); 4589 } 4590 4591 /* 4592 * If we got an error on a leaf device, convert it to ENXIO 4593 * if the device is not accessible at all. 4594 */ 4595 if (zio->io_error && vd != NULL && vd->vdev_ops->vdev_op_leaf && 4596 !vdev_accessible(vd, zio)) 4597 zio->io_error = SET_ERROR(ENXIO); 4598 4599 /* 4600 * If we can't write to an interior vdev (mirror or RAID-Z), 4601 * set vdev_cant_write so that we stop trying to allocate from it. 4602 */ 4603 if (zio->io_error == ENXIO && zio->io_type == ZIO_TYPE_WRITE && 4604 vd != NULL && !vd->vdev_ops->vdev_op_leaf) { 4605 vdev_dbgmsg(vd, "zio_vdev_io_assess(zio=%px) setting " 4606 "cant_write=TRUE due to write failure with ENXIO", 4607 zio); 4608 vd->vdev_cant_write = B_TRUE; 4609 } 4610 4611 /* 4612 * If a cache flush returns ENOTSUP or ENOTTY, we know that no future 4613 * attempts will ever succeed. In this case we set a persistent 4614 * boolean flag so that we don't bother with it in the future. 4615 */ 4616 if ((zio->io_error == ENOTSUP || zio->io_error == ENOTTY) && 4617 zio->io_type == ZIO_TYPE_FLUSH && vd != NULL) 4618 vd->vdev_nowritecache = B_TRUE; 4619 4620 if (zio->io_error) 4621 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 4622 4623 return (zio); 4624 } 4625 4626 void 4627 zio_vdev_io_reissue(zio_t *zio) 4628 { 4629 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START); 4630 ASSERT(zio->io_error == 0); 4631 4632 zio->io_stage >>= 1; 4633 } 4634 4635 void 4636 zio_vdev_io_redone(zio_t *zio) 4637 { 4638 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_DONE); 4639 4640 zio->io_stage >>= 1; 4641 } 4642 4643 void 4644 zio_vdev_io_bypass(zio_t *zio) 4645 { 4646 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START); 4647 ASSERT(zio->io_error == 0); 4648 4649 zio->io_flags |= ZIO_FLAG_IO_BYPASS; 4650 zio->io_stage = ZIO_STAGE_VDEV_IO_ASSESS >> 1; 4651 } 4652 4653 /* 4654 * ========================================================================== 4655 * Encrypt and store encryption parameters 4656 * ========================================================================== 4657 */ 4658 4659 4660 /* 4661 * This function is used for ZIO_STAGE_ENCRYPT. It is responsible for 4662 * managing the storage of encryption parameters and passing them to the 4663 * lower-level encryption functions. 4664 */ 4665 static zio_t * 4666 zio_encrypt(zio_t *zio) 4667 { 4668 zio_prop_t *zp = &zio->io_prop; 4669 spa_t *spa = zio->io_spa; 4670 blkptr_t *bp = zio->io_bp; 4671 uint64_t psize = BP_GET_PSIZE(bp); 4672 uint64_t dsobj = zio->io_bookmark.zb_objset; 4673 dmu_object_type_t ot = BP_GET_TYPE(bp); 4674 void *enc_buf = NULL; 4675 abd_t *eabd = NULL; 4676 uint8_t salt[ZIO_DATA_SALT_LEN]; 4677 uint8_t iv[ZIO_DATA_IV_LEN]; 4678 uint8_t mac[ZIO_DATA_MAC_LEN]; 4679 boolean_t no_crypt = B_FALSE; 4680 4681 /* the root zio already encrypted the data */ 4682 if (zio->io_child_type == ZIO_CHILD_GANG) 4683 return (zio); 4684 4685 /* only ZIL blocks are re-encrypted on rewrite */ 4686 if (!IO_IS_ALLOCATING(zio) && ot != DMU_OT_INTENT_LOG) 4687 return (zio); 4688 4689 if (!(zp->zp_encrypt || BP_IS_ENCRYPTED(bp))) { 4690 BP_SET_CRYPT(bp, B_FALSE); 4691 return (zio); 4692 } 4693 4694 /* if we are doing raw encryption set the provided encryption params */ 4695 if (zio->io_flags & ZIO_FLAG_RAW_ENCRYPT) { 4696 ASSERT0(BP_GET_LEVEL(bp)); 4697 BP_SET_CRYPT(bp, B_TRUE); 4698 BP_SET_BYTEORDER(bp, zp->zp_byteorder); 4699 if (ot != DMU_OT_OBJSET) 4700 zio_crypt_encode_mac_bp(bp, zp->zp_mac); 4701 4702 /* dnode blocks must be written out in the provided byteorder */ 4703 if (zp->zp_byteorder != ZFS_HOST_BYTEORDER && 4704 ot == DMU_OT_DNODE) { 4705 void *bswap_buf = zio_buf_alloc(psize); 4706 abd_t *babd = abd_get_from_buf(bswap_buf, psize); 4707 4708 ASSERT3U(BP_GET_COMPRESS(bp), ==, ZIO_COMPRESS_OFF); 4709 abd_copy_to_buf(bswap_buf, zio->io_abd, psize); 4710 dmu_ot_byteswap[DMU_OT_BYTESWAP(ot)].ob_func(bswap_buf, 4711 psize); 4712 4713 abd_take_ownership_of_buf(babd, B_TRUE); 4714 zio_push_transform(zio, babd, psize, psize, NULL); 4715 } 4716 4717 if (DMU_OT_IS_ENCRYPTED(ot)) 4718 zio_crypt_encode_params_bp(bp, zp->zp_salt, zp->zp_iv); 4719 return (zio); 4720 } 4721 4722 /* indirect blocks only maintain a cksum of the lower level MACs */ 4723 if (BP_GET_LEVEL(bp) > 0) { 4724 BP_SET_CRYPT(bp, B_TRUE); 4725 VERIFY0(zio_crypt_do_indirect_mac_checksum_abd(B_TRUE, 4726 zio->io_orig_abd, BP_GET_LSIZE(bp), BP_SHOULD_BYTESWAP(bp), 4727 mac)); 4728 zio_crypt_encode_mac_bp(bp, mac); 4729 return (zio); 4730 } 4731 4732 /* 4733 * Objset blocks are a special case since they have 2 256-bit MACs 4734 * embedded within them. 4735 */ 4736 if (ot == DMU_OT_OBJSET) { 4737 ASSERT0(DMU_OT_IS_ENCRYPTED(ot)); 4738 ASSERT3U(BP_GET_COMPRESS(bp), ==, ZIO_COMPRESS_OFF); 4739 BP_SET_CRYPT(bp, B_TRUE); 4740 VERIFY0(spa_do_crypt_objset_mac_abd(B_TRUE, spa, dsobj, 4741 zio->io_abd, psize, BP_SHOULD_BYTESWAP(bp))); 4742 return (zio); 4743 } 4744 4745 /* unencrypted object types are only authenticated with a MAC */ 4746 if (!DMU_OT_IS_ENCRYPTED(ot)) { 4747 BP_SET_CRYPT(bp, B_TRUE); 4748 VERIFY0(spa_do_crypt_mac_abd(B_TRUE, spa, dsobj, 4749 zio->io_abd, psize, mac)); 4750 zio_crypt_encode_mac_bp(bp, mac); 4751 return (zio); 4752 } 4753 4754 /* 4755 * Later passes of sync-to-convergence may decide to rewrite data 4756 * in place to avoid more disk reallocations. This presents a problem 4757 * for encryption because this constitutes rewriting the new data with 4758 * the same encryption key and IV. However, this only applies to blocks 4759 * in the MOS (particularly the spacemaps) and we do not encrypt the 4760 * MOS. We assert that the zio is allocating or an intent log write 4761 * to enforce this. 4762 */ 4763 ASSERT(IO_IS_ALLOCATING(zio) || ot == DMU_OT_INTENT_LOG); 4764 ASSERT(BP_GET_LEVEL(bp) == 0 || ot == DMU_OT_INTENT_LOG); 4765 ASSERT(spa_feature_is_active(spa, SPA_FEATURE_ENCRYPTION)); 4766 ASSERT3U(psize, !=, 0); 4767 4768 enc_buf = zio_buf_alloc(psize); 4769 eabd = abd_get_from_buf(enc_buf, psize); 4770 abd_take_ownership_of_buf(eabd, B_TRUE); 4771 4772 /* 4773 * For an explanation of what encryption parameters are stored 4774 * where, see the block comment in zio_crypt.c. 4775 */ 4776 if (ot == DMU_OT_INTENT_LOG) { 4777 zio_crypt_decode_params_bp(bp, salt, iv); 4778 } else { 4779 BP_SET_CRYPT(bp, B_TRUE); 4780 } 4781 4782 /* Perform the encryption. This should not fail */ 4783 VERIFY0(spa_do_crypt_abd(B_TRUE, spa, &zio->io_bookmark, 4784 BP_GET_TYPE(bp), BP_GET_DEDUP(bp), BP_SHOULD_BYTESWAP(bp), 4785 salt, iv, mac, psize, zio->io_abd, eabd, &no_crypt)); 4786 4787 /* encode encryption metadata into the bp */ 4788 if (ot == DMU_OT_INTENT_LOG) { 4789 /* 4790 * ZIL blocks store the MAC in the embedded checksum, so the 4791 * transform must always be applied. 4792 */ 4793 zio_crypt_encode_mac_zil(enc_buf, mac); 4794 zio_push_transform(zio, eabd, psize, psize, NULL); 4795 } else { 4796 BP_SET_CRYPT(bp, B_TRUE); 4797 zio_crypt_encode_params_bp(bp, salt, iv); 4798 zio_crypt_encode_mac_bp(bp, mac); 4799 4800 if (no_crypt) { 4801 ASSERT3U(ot, ==, DMU_OT_DNODE); 4802 abd_free(eabd); 4803 } else { 4804 zio_push_transform(zio, eabd, psize, psize, NULL); 4805 } 4806 } 4807 4808 return (zio); 4809 } 4810 4811 /* 4812 * ========================================================================== 4813 * Generate and verify checksums 4814 * ========================================================================== 4815 */ 4816 static zio_t * 4817 zio_checksum_generate(zio_t *zio) 4818 { 4819 blkptr_t *bp = zio->io_bp; 4820 enum zio_checksum checksum; 4821 4822 if (bp == NULL) { 4823 /* 4824 * This is zio_write_phys(). 4825 * We're either generating a label checksum, or none at all. 4826 */ 4827 checksum = zio->io_prop.zp_checksum; 4828 4829 if (checksum == ZIO_CHECKSUM_OFF) 4830 return (zio); 4831 4832 ASSERT(checksum == ZIO_CHECKSUM_LABEL); 4833 } else { 4834 if (BP_IS_GANG(bp) && zio->io_child_type == ZIO_CHILD_GANG) { 4835 ASSERT(!IO_IS_ALLOCATING(zio)); 4836 checksum = ZIO_CHECKSUM_GANG_HEADER; 4837 } else { 4838 checksum = BP_GET_CHECKSUM(bp); 4839 } 4840 } 4841 4842 zio_checksum_compute(zio, checksum, zio->io_abd, zio->io_size); 4843 4844 return (zio); 4845 } 4846 4847 static zio_t * 4848 zio_checksum_verify(zio_t *zio) 4849 { 4850 zio_bad_cksum_t info; 4851 blkptr_t *bp = zio->io_bp; 4852 int error; 4853 4854 ASSERT(zio->io_vd != NULL); 4855 4856 if (bp == NULL) { 4857 /* 4858 * This is zio_read_phys(). 4859 * We're either verifying a label checksum, or nothing at all. 4860 */ 4861 if (zio->io_prop.zp_checksum == ZIO_CHECKSUM_OFF) 4862 return (zio); 4863 4864 ASSERT3U(zio->io_prop.zp_checksum, ==, ZIO_CHECKSUM_LABEL); 4865 } 4866 4867 if ((error = zio_checksum_error(zio, &info)) != 0) { 4868 zio->io_error = error; 4869 if (error == ECKSUM && 4870 !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) { 4871 mutex_enter(&zio->io_vd->vdev_stat_lock); 4872 zio->io_vd->vdev_stat.vs_checksum_errors++; 4873 mutex_exit(&zio->io_vd->vdev_stat_lock); 4874 (void) zfs_ereport_start_checksum(zio->io_spa, 4875 zio->io_vd, &zio->io_bookmark, zio, 4876 zio->io_offset, zio->io_size, &info); 4877 } 4878 } 4879 4880 return (zio); 4881 } 4882 4883 static zio_t * 4884 zio_dio_checksum_verify(zio_t *zio) 4885 { 4886 zio_t *pio = zio_unique_parent(zio); 4887 int error; 4888 4889 ASSERT3P(zio->io_vd, !=, NULL); 4890 ASSERT3P(zio->io_bp, !=, NULL); 4891 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV); 4892 ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE); 4893 ASSERT3B(pio->io_prop.zp_direct_write, ==, B_TRUE); 4894 ASSERT3U(pio->io_child_type, ==, ZIO_CHILD_LOGICAL); 4895 4896 if (zfs_vdev_direct_write_verify == 0 || zio->io_error != 0) 4897 goto out; 4898 4899 if ((error = zio_checksum_error(zio, NULL)) != 0) { 4900 zio->io_error = error; 4901 if (error == ECKSUM) { 4902 mutex_enter(&zio->io_vd->vdev_stat_lock); 4903 zio->io_vd->vdev_stat.vs_dio_verify_errors++; 4904 mutex_exit(&zio->io_vd->vdev_stat_lock); 4905 zio->io_error = SET_ERROR(EIO); 4906 zio->io_flags |= ZIO_FLAG_DIO_CHKSUM_ERR; 4907 4908 /* 4909 * The EIO error must be propagated up to the logical 4910 * parent ZIO in zio_notify_parent() so it can be 4911 * returned to dmu_write_abd(). 4912 */ 4913 zio->io_flags &= ~ZIO_FLAG_DONT_PROPAGATE; 4914 4915 (void) zfs_ereport_post(FM_EREPORT_ZFS_DIO_VERIFY, 4916 zio->io_spa, zio->io_vd, &zio->io_bookmark, 4917 zio, 0); 4918 } 4919 } 4920 4921 out: 4922 return (zio); 4923 } 4924 4925 4926 /* 4927 * Called by RAID-Z to ensure we don't compute the checksum twice. 4928 */ 4929 void 4930 zio_checksum_verified(zio_t *zio) 4931 { 4932 zio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY; 4933 } 4934 4935 /* 4936 * ========================================================================== 4937 * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other. 4938 * An error of 0 indicates success. ENXIO indicates whole-device failure, 4939 * which may be transient (e.g. unplugged) or permanent. ECKSUM and EIO 4940 * indicate errors that are specific to one I/O, and most likely permanent. 4941 * Any other error is presumed to be worse because we weren't expecting it. 4942 * ========================================================================== 4943 */ 4944 int 4945 zio_worst_error(int e1, int e2) 4946 { 4947 static int zio_error_rank[] = { 0, ENXIO, ECKSUM, EIO }; 4948 int r1, r2; 4949 4950 for (r1 = 0; r1 < sizeof (zio_error_rank) / sizeof (int); r1++) 4951 if (e1 == zio_error_rank[r1]) 4952 break; 4953 4954 for (r2 = 0; r2 < sizeof (zio_error_rank) / sizeof (int); r2++) 4955 if (e2 == zio_error_rank[r2]) 4956 break; 4957 4958 return (r1 > r2 ? e1 : e2); 4959 } 4960 4961 /* 4962 * ========================================================================== 4963 * I/O completion 4964 * ========================================================================== 4965 */ 4966 static zio_t * 4967 zio_ready(zio_t *zio) 4968 { 4969 blkptr_t *bp = zio->io_bp; 4970 zio_t *pio, *pio_next; 4971 zio_link_t *zl = NULL; 4972 4973 if (zio_wait_for_children(zio, ZIO_CHILD_LOGICAL_BIT | 4974 ZIO_CHILD_GANG_BIT | ZIO_CHILD_DDT_BIT, ZIO_WAIT_READY)) { 4975 return (NULL); 4976 } 4977 4978 if (zio->io_ready) { 4979 ASSERT(IO_IS_ALLOCATING(zio)); 4980 ASSERT(BP_GET_LOGICAL_BIRTH(bp) == zio->io_txg || 4981 BP_IS_HOLE(bp) || (zio->io_flags & ZIO_FLAG_NOPWRITE)); 4982 ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0); 4983 4984 zio->io_ready(zio); 4985 } 4986 4987 #ifdef ZFS_DEBUG 4988 if (bp != NULL && bp != &zio->io_bp_copy) 4989 zio->io_bp_copy = *bp; 4990 #endif 4991 4992 if (zio->io_error != 0) { 4993 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE; 4994 4995 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 4996 ASSERT(IO_IS_ALLOCATING(zio)); 4997 ASSERT(zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE); 4998 ASSERT(zio->io_metaslab_class != NULL); 4999 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 5000 5001 /* 5002 * We were unable to allocate anything, unreserve and 5003 * issue the next I/O to allocate. 5004 */ 5005 metaslab_class_throttle_unreserve( 5006 zio->io_metaslab_class, zio->io_prop.zp_copies, 5007 zio->io_allocator, zio); 5008 zio_allocate_dispatch(zio->io_spa, zio->io_allocator); 5009 } 5010 } 5011 5012 mutex_enter(&zio->io_lock); 5013 zio->io_state[ZIO_WAIT_READY] = 1; 5014 pio = zio_walk_parents(zio, &zl); 5015 mutex_exit(&zio->io_lock); 5016 5017 /* 5018 * As we notify zio's parents, new parents could be added. 5019 * New parents go to the head of zio's io_parent_list, however, 5020 * so we will (correctly) not notify them. The remainder of zio's 5021 * io_parent_list, from 'pio_next' onward, cannot change because 5022 * all parents must wait for us to be done before they can be done. 5023 */ 5024 for (; pio != NULL; pio = pio_next) { 5025 pio_next = zio_walk_parents(zio, &zl); 5026 zio_notify_parent(pio, zio, ZIO_WAIT_READY, NULL); 5027 } 5028 5029 if (zio->io_flags & ZIO_FLAG_NODATA) { 5030 if (bp != NULL && BP_IS_GANG(bp)) { 5031 zio->io_flags &= ~ZIO_FLAG_NODATA; 5032 } else { 5033 ASSERT((uintptr_t)zio->io_abd < SPA_MAXBLOCKSIZE); 5034 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES; 5035 } 5036 } 5037 5038 if (zio_injection_enabled && 5039 zio->io_spa->spa_syncing_txg == zio->io_txg) 5040 zio_handle_ignored_writes(zio); 5041 5042 return (zio); 5043 } 5044 5045 /* 5046 * Update the allocation throttle accounting. 5047 */ 5048 static void 5049 zio_dva_throttle_done(zio_t *zio) 5050 { 5051 zio_t *lio __maybe_unused = zio->io_logical; 5052 zio_t *pio = zio_unique_parent(zio); 5053 vdev_t *vd = zio->io_vd; 5054 int flags = METASLAB_ASYNC_ALLOC; 5055 5056 ASSERT3P(zio->io_bp, !=, NULL); 5057 ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE); 5058 ASSERT3U(zio->io_priority, ==, ZIO_PRIORITY_ASYNC_WRITE); 5059 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV); 5060 ASSERT(vd != NULL); 5061 ASSERT3P(vd, ==, vd->vdev_top); 5062 ASSERT(zio_injection_enabled || !(zio->io_flags & ZIO_FLAG_IO_RETRY)); 5063 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REPAIR)); 5064 ASSERT(zio->io_flags & ZIO_FLAG_IO_ALLOCATING); 5065 ASSERT(!(lio->io_flags & ZIO_FLAG_IO_REWRITE)); 5066 ASSERT(!(lio->io_orig_flags & ZIO_FLAG_NODATA)); 5067 5068 /* 5069 * Parents of gang children can have two flavors -- ones that 5070 * allocated the gang header (will have ZIO_FLAG_IO_REWRITE set) 5071 * and ones that allocated the constituent blocks. The allocation 5072 * throttle needs to know the allocating parent zio so we must find 5073 * it here. 5074 */ 5075 if (pio->io_child_type == ZIO_CHILD_GANG) { 5076 /* 5077 * If our parent is a rewrite gang child then our grandparent 5078 * would have been the one that performed the allocation. 5079 */ 5080 if (pio->io_flags & ZIO_FLAG_IO_REWRITE) 5081 pio = zio_unique_parent(pio); 5082 flags |= METASLAB_GANG_CHILD; 5083 } 5084 5085 ASSERT(IO_IS_ALLOCATING(pio)); 5086 ASSERT(ZIO_HAS_ALLOCATOR(pio)); 5087 ASSERT3P(zio, !=, zio->io_logical); 5088 ASSERT(zio->io_logical != NULL); 5089 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REPAIR)); 5090 ASSERT0(zio->io_flags & ZIO_FLAG_NOPWRITE); 5091 ASSERT(zio->io_metaslab_class != NULL); 5092 5093 mutex_enter(&pio->io_lock); 5094 metaslab_group_alloc_decrement(zio->io_spa, vd->vdev_id, pio, flags, 5095 pio->io_allocator, B_TRUE); 5096 mutex_exit(&pio->io_lock); 5097 5098 metaslab_class_throttle_unreserve(zio->io_metaslab_class, 1, 5099 pio->io_allocator, pio); 5100 5101 /* 5102 * Call into the pipeline to see if there is more work that 5103 * needs to be done. If there is work to be done it will be 5104 * dispatched to another taskq thread. 5105 */ 5106 zio_allocate_dispatch(zio->io_spa, pio->io_allocator); 5107 } 5108 5109 static zio_t * 5110 zio_done(zio_t *zio) 5111 { 5112 /* 5113 * Always attempt to keep stack usage minimal here since 5114 * we can be called recursively up to 19 levels deep. 5115 */ 5116 const uint64_t psize = zio->io_size; 5117 zio_t *pio, *pio_next; 5118 zio_link_t *zl = NULL; 5119 5120 /* 5121 * If our children haven't all completed, 5122 * wait for them and then repeat this pipeline stage. 5123 */ 5124 if (zio_wait_for_children(zio, ZIO_CHILD_ALL_BITS, ZIO_WAIT_DONE)) { 5125 return (NULL); 5126 } 5127 5128 /* 5129 * If the allocation throttle is enabled, then update the accounting. 5130 * We only track child I/Os that are part of an allocating async 5131 * write. We must do this since the allocation is performed 5132 * by the logical I/O but the actual write is done by child I/Os. 5133 */ 5134 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING && 5135 zio->io_child_type == ZIO_CHILD_VDEV) { 5136 ASSERT(zio->io_metaslab_class != NULL); 5137 ASSERT(zio->io_metaslab_class->mc_alloc_throttle_enabled); 5138 zio_dva_throttle_done(zio); 5139 } 5140 5141 /* 5142 * If the allocation throttle is enabled, verify that 5143 * we have decremented the refcounts for every I/O that was throttled. 5144 */ 5145 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING) { 5146 ASSERT(zio->io_type == ZIO_TYPE_WRITE); 5147 ASSERT(zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE); 5148 ASSERT(zio->io_bp != NULL); 5149 ASSERT(ZIO_HAS_ALLOCATOR(zio)); 5150 5151 metaslab_group_alloc_verify(zio->io_spa, zio->io_bp, zio, 5152 zio->io_allocator); 5153 VERIFY(zfs_refcount_not_held(&zio->io_metaslab_class-> 5154 mc_allocator[zio->io_allocator].mca_alloc_slots, zio)); 5155 } 5156 5157 5158 for (int c = 0; c < ZIO_CHILD_TYPES; c++) 5159 for (int w = 0; w < ZIO_WAIT_TYPES; w++) 5160 ASSERT(zio->io_children[c][w] == 0); 5161 5162 if (zio->io_bp != NULL && !BP_IS_EMBEDDED(zio->io_bp)) { 5163 ASSERT(zio->io_bp->blk_pad[0] == 0); 5164 ASSERT(zio->io_bp->blk_pad[1] == 0); 5165 ASSERT(memcmp(zio->io_bp, &zio->io_bp_copy, 5166 sizeof (blkptr_t)) == 0 || 5167 (zio->io_bp == zio_unique_parent(zio)->io_bp)); 5168 if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(zio->io_bp) && 5169 zio->io_bp_override == NULL && 5170 !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) { 5171 ASSERT3U(zio->io_prop.zp_copies, <=, 5172 BP_GET_NDVAS(zio->io_bp)); 5173 ASSERT(BP_COUNT_GANG(zio->io_bp) == 0 || 5174 (BP_COUNT_GANG(zio->io_bp) == 5175 BP_GET_NDVAS(zio->io_bp))); 5176 } 5177 if (zio->io_flags & ZIO_FLAG_NOPWRITE) 5178 VERIFY(BP_EQUAL(zio->io_bp, &zio->io_bp_orig)); 5179 } 5180 5181 /* 5182 * If there were child vdev/gang/ddt errors, they apply to us now. 5183 */ 5184 zio_inherit_child_errors(zio, ZIO_CHILD_VDEV); 5185 zio_inherit_child_errors(zio, ZIO_CHILD_GANG); 5186 zio_inherit_child_errors(zio, ZIO_CHILD_DDT); 5187 5188 /* 5189 * If the I/O on the transformed data was successful, generate any 5190 * checksum reports now while we still have the transformed data. 5191 */ 5192 if (zio->io_error == 0) { 5193 while (zio->io_cksum_report != NULL) { 5194 zio_cksum_report_t *zcr = zio->io_cksum_report; 5195 uint64_t align = zcr->zcr_align; 5196 uint64_t asize = P2ROUNDUP(psize, align); 5197 abd_t *adata = zio->io_abd; 5198 5199 if (adata != NULL && asize != psize) { 5200 adata = abd_alloc(asize, B_TRUE); 5201 abd_copy(adata, zio->io_abd, psize); 5202 abd_zero_off(adata, psize, asize - psize); 5203 } 5204 5205 zio->io_cksum_report = zcr->zcr_next; 5206 zcr->zcr_next = NULL; 5207 zcr->zcr_finish(zcr, adata); 5208 zfs_ereport_free_checksum(zcr); 5209 5210 if (adata != NULL && asize != psize) 5211 abd_free(adata); 5212 } 5213 } 5214 5215 zio_pop_transforms(zio); /* note: may set zio->io_error */ 5216 5217 vdev_stat_update(zio, psize); 5218 5219 /* 5220 * If this I/O is attached to a particular vdev is slow, exceeding 5221 * 30 seconds to complete, post an error described the I/O delay. 5222 * We ignore these errors if the device is currently unavailable. 5223 */ 5224 if (zio->io_delay >= MSEC2NSEC(zio_slow_io_ms)) { 5225 if (zio->io_vd != NULL && !vdev_is_dead(zio->io_vd)) { 5226 /* 5227 * We want to only increment our slow IO counters if 5228 * the IO is valid (i.e. not if the drive is removed). 5229 * 5230 * zfs_ereport_post() will also do these checks, but 5231 * it can also ratelimit and have other failures, so we 5232 * need to increment the slow_io counters independent 5233 * of it. 5234 */ 5235 if (zfs_ereport_is_valid(FM_EREPORT_ZFS_DELAY, 5236 zio->io_spa, zio->io_vd, zio)) { 5237 mutex_enter(&zio->io_vd->vdev_stat_lock); 5238 zio->io_vd->vdev_stat.vs_slow_ios++; 5239 mutex_exit(&zio->io_vd->vdev_stat_lock); 5240 5241 (void) zfs_ereport_post(FM_EREPORT_ZFS_DELAY, 5242 zio->io_spa, zio->io_vd, &zio->io_bookmark, 5243 zio, 0); 5244 } 5245 } 5246 } 5247 5248 if (zio->io_error) { 5249 /* 5250 * If this I/O is attached to a particular vdev, 5251 * generate an error message describing the I/O failure 5252 * at the block level. We ignore these errors if the 5253 * device is currently unavailable. 5254 */ 5255 if (zio->io_error != ECKSUM && zio->io_vd != NULL && 5256 !vdev_is_dead(zio->io_vd) && 5257 !(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR)) { 5258 int ret = zfs_ereport_post(FM_EREPORT_ZFS_IO, 5259 zio->io_spa, zio->io_vd, &zio->io_bookmark, zio, 0); 5260 if (ret != EALREADY) { 5261 mutex_enter(&zio->io_vd->vdev_stat_lock); 5262 if (zio->io_type == ZIO_TYPE_READ) 5263 zio->io_vd->vdev_stat.vs_read_errors++; 5264 else if (zio->io_type == ZIO_TYPE_WRITE) 5265 zio->io_vd->vdev_stat.vs_write_errors++; 5266 mutex_exit(&zio->io_vd->vdev_stat_lock); 5267 } 5268 } 5269 5270 if ((zio->io_error == EIO || !(zio->io_flags & 5271 (ZIO_FLAG_SPECULATIVE | ZIO_FLAG_DONT_PROPAGATE))) && 5272 !(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR) && 5273 zio == zio->io_logical) { 5274 /* 5275 * For logical I/O requests, tell the SPA to log the 5276 * error and generate a logical data ereport. 5277 */ 5278 spa_log_error(zio->io_spa, &zio->io_bookmark, 5279 BP_GET_LOGICAL_BIRTH(zio->io_bp)); 5280 (void) zfs_ereport_post(FM_EREPORT_ZFS_DATA, 5281 zio->io_spa, NULL, &zio->io_bookmark, zio, 0); 5282 } 5283 } 5284 5285 if (zio->io_error && zio == zio->io_logical) { 5286 /* 5287 * Determine whether zio should be reexecuted. This will 5288 * propagate all the way to the root via zio_notify_parent(). 5289 */ 5290 ASSERT(zio->io_vd == NULL && zio->io_bp != NULL); 5291 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 5292 5293 if (IO_IS_ALLOCATING(zio) && 5294 !(zio->io_flags & ZIO_FLAG_CANFAIL) && 5295 !(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR)) { 5296 if (zio->io_error != ENOSPC) 5297 zio->io_reexecute |= ZIO_REEXECUTE_NOW; 5298 else 5299 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 5300 } 5301 5302 if ((zio->io_type == ZIO_TYPE_READ || 5303 zio->io_type == ZIO_TYPE_FREE) && 5304 !(zio->io_flags & ZIO_FLAG_SCAN_THREAD) && 5305 zio->io_error == ENXIO && 5306 spa_load_state(zio->io_spa) == SPA_LOAD_NONE && 5307 spa_get_failmode(zio->io_spa) != ZIO_FAILURE_MODE_CONTINUE) 5308 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 5309 5310 if (!(zio->io_flags & ZIO_FLAG_CANFAIL) && !zio->io_reexecute) 5311 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND; 5312 5313 /* 5314 * Here is a possibly good place to attempt to do 5315 * either combinatorial reconstruction or error correction 5316 * based on checksums. It also might be a good place 5317 * to send out preliminary ereports before we suspend 5318 * processing. 5319 */ 5320 } 5321 5322 /* 5323 * If there were logical child errors, they apply to us now. 5324 * We defer this until now to avoid conflating logical child 5325 * errors with errors that happened to the zio itself when 5326 * updating vdev stats and reporting FMA events above. 5327 */ 5328 zio_inherit_child_errors(zio, ZIO_CHILD_LOGICAL); 5329 5330 if ((zio->io_error || zio->io_reexecute) && 5331 IO_IS_ALLOCATING(zio) && zio->io_gang_leader == zio && 5332 !(zio->io_flags & (ZIO_FLAG_IO_REWRITE | ZIO_FLAG_NOPWRITE))) 5333 zio_dva_unallocate(zio, zio->io_gang_tree, zio->io_bp); 5334 5335 zio_gang_tree_free(&zio->io_gang_tree); 5336 5337 /* 5338 * Godfather I/Os should never suspend. 5339 */ 5340 if ((zio->io_flags & ZIO_FLAG_GODFATHER) && 5341 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) 5342 zio->io_reexecute &= ~ZIO_REEXECUTE_SUSPEND; 5343 5344 if (zio->io_reexecute) { 5345 /* 5346 * A Direct I/O write that has a checksum verify error should 5347 * not attempt to reexecute. Instead, EAGAIN should just be 5348 * propagated back up so the write can be attempt to be issued 5349 * through the ARC. 5350 */ 5351 ASSERT(!(zio->io_flags & ZIO_FLAG_DIO_CHKSUM_ERR)); 5352 5353 /* 5354 * This is a logical I/O that wants to reexecute. 5355 * 5356 * Reexecute is top-down. When an i/o fails, if it's not 5357 * the root, it simply notifies its parent and sticks around. 5358 * The parent, seeing that it still has children in zio_done(), 5359 * does the same. This percolates all the way up to the root. 5360 * The root i/o will reexecute or suspend the entire tree. 5361 * 5362 * This approach ensures that zio_reexecute() honors 5363 * all the original i/o dependency relationships, e.g. 5364 * parents not executing until children are ready. 5365 */ 5366 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL); 5367 5368 zio->io_gang_leader = NULL; 5369 5370 mutex_enter(&zio->io_lock); 5371 zio->io_state[ZIO_WAIT_DONE] = 1; 5372 mutex_exit(&zio->io_lock); 5373 5374 /* 5375 * "The Godfather" I/O monitors its children but is 5376 * not a true parent to them. It will track them through 5377 * the pipeline but severs its ties whenever they get into 5378 * trouble (e.g. suspended). This allows "The Godfather" 5379 * I/O to return status without blocking. 5380 */ 5381 zl = NULL; 5382 for (pio = zio_walk_parents(zio, &zl); pio != NULL; 5383 pio = pio_next) { 5384 zio_link_t *remove_zl = zl; 5385 pio_next = zio_walk_parents(zio, &zl); 5386 5387 if ((pio->io_flags & ZIO_FLAG_GODFATHER) && 5388 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) { 5389 zio_remove_child(pio, zio, remove_zl); 5390 /* 5391 * This is a rare code path, so we don't 5392 * bother with "next_to_execute". 5393 */ 5394 zio_notify_parent(pio, zio, ZIO_WAIT_DONE, 5395 NULL); 5396 } 5397 } 5398 5399 if ((pio = zio_unique_parent(zio)) != NULL) { 5400 /* 5401 * We're not a root i/o, so there's nothing to do 5402 * but notify our parent. Don't propagate errors 5403 * upward since we haven't permanently failed yet. 5404 */ 5405 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER)); 5406 zio->io_flags |= ZIO_FLAG_DONT_PROPAGATE; 5407 /* 5408 * This is a rare code path, so we don't bother with 5409 * "next_to_execute". 5410 */ 5411 zio_notify_parent(pio, zio, ZIO_WAIT_DONE, NULL); 5412 } else if (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND) { 5413 /* 5414 * We'd fail again if we reexecuted now, so suspend 5415 * until conditions improve (e.g. device comes online). 5416 */ 5417 zio_suspend(zio->io_spa, zio, ZIO_SUSPEND_IOERR); 5418 } else { 5419 /* 5420 * Reexecution is potentially a huge amount of work. 5421 * Hand it off to the otherwise-unused claim taskq. 5422 */ 5423 spa_taskq_dispatch(zio->io_spa, 5424 ZIO_TYPE_CLAIM, ZIO_TASKQ_ISSUE, 5425 zio_reexecute, zio, B_FALSE); 5426 } 5427 return (NULL); 5428 } 5429 5430 ASSERT(list_is_empty(&zio->io_child_list)); 5431 ASSERT(zio->io_reexecute == 0); 5432 ASSERT(zio->io_error == 0 || (zio->io_flags & ZIO_FLAG_CANFAIL)); 5433 5434 /* 5435 * Report any checksum errors, since the I/O is complete. 5436 */ 5437 while (zio->io_cksum_report != NULL) { 5438 zio_cksum_report_t *zcr = zio->io_cksum_report; 5439 zio->io_cksum_report = zcr->zcr_next; 5440 zcr->zcr_next = NULL; 5441 zcr->zcr_finish(zcr, NULL); 5442 zfs_ereport_free_checksum(zcr); 5443 } 5444 5445 /* 5446 * It is the responsibility of the done callback to ensure that this 5447 * particular zio is no longer discoverable for adoption, and as 5448 * such, cannot acquire any new parents. 5449 */ 5450 if (zio->io_done) 5451 zio->io_done(zio); 5452 5453 mutex_enter(&zio->io_lock); 5454 zio->io_state[ZIO_WAIT_DONE] = 1; 5455 mutex_exit(&zio->io_lock); 5456 5457 /* 5458 * We are done executing this zio. We may want to execute a parent 5459 * next. See the comment in zio_notify_parent(). 5460 */ 5461 zio_t *next_to_execute = NULL; 5462 zl = NULL; 5463 for (pio = zio_walk_parents(zio, &zl); pio != NULL; pio = pio_next) { 5464 zio_link_t *remove_zl = zl; 5465 pio_next = zio_walk_parents(zio, &zl); 5466 zio_remove_child(pio, zio, remove_zl); 5467 zio_notify_parent(pio, zio, ZIO_WAIT_DONE, &next_to_execute); 5468 } 5469 5470 if (zio->io_waiter != NULL) { 5471 mutex_enter(&zio->io_lock); 5472 zio->io_executor = NULL; 5473 cv_broadcast(&zio->io_cv); 5474 mutex_exit(&zio->io_lock); 5475 } else { 5476 zio_destroy(zio); 5477 } 5478 5479 return (next_to_execute); 5480 } 5481 5482 /* 5483 * ========================================================================== 5484 * I/O pipeline definition 5485 * ========================================================================== 5486 */ 5487 static zio_pipe_stage_t *zio_pipeline[] = { 5488 NULL, 5489 zio_read_bp_init, 5490 zio_write_bp_init, 5491 zio_free_bp_init, 5492 zio_issue_async, 5493 zio_write_compress, 5494 zio_encrypt, 5495 zio_checksum_generate, 5496 zio_nop_write, 5497 zio_brt_free, 5498 zio_ddt_read_start, 5499 zio_ddt_read_done, 5500 zio_ddt_write, 5501 zio_ddt_free, 5502 zio_gang_assemble, 5503 zio_gang_issue, 5504 zio_dva_throttle, 5505 zio_dva_allocate, 5506 zio_dva_free, 5507 zio_dva_claim, 5508 zio_ready, 5509 zio_vdev_io_start, 5510 zio_vdev_io_done, 5511 zio_vdev_io_assess, 5512 zio_checksum_verify, 5513 zio_dio_checksum_verify, 5514 zio_done 5515 }; 5516 5517 5518 5519 5520 /* 5521 * Compare two zbookmark_phys_t's to see which we would reach first in a 5522 * pre-order traversal of the object tree. 5523 * 5524 * This is simple in every case aside from the meta-dnode object. For all other 5525 * objects, we traverse them in order (object 1 before object 2, and so on). 5526 * However, all of these objects are traversed while traversing object 0, since 5527 * the data it points to is the list of objects. Thus, we need to convert to a 5528 * canonical representation so we can compare meta-dnode bookmarks to 5529 * non-meta-dnode bookmarks. 5530 * 5531 * We do this by calculating "equivalents" for each field of the zbookmark. 5532 * zbookmarks outside of the meta-dnode use their own object and level, and 5533 * calculate the level 0 equivalent (the first L0 blkid that is contained in the 5534 * blocks this bookmark refers to) by multiplying their blkid by their span 5535 * (the number of L0 blocks contained within one block at their level). 5536 * zbookmarks inside the meta-dnode calculate their object equivalent 5537 * (which is L0equiv * dnodes per data block), use 0 for their L0equiv, and use 5538 * level + 1<<31 (any value larger than a level could ever be) for their level. 5539 * This causes them to always compare before a bookmark in their object 5540 * equivalent, compare appropriately to bookmarks in other objects, and to 5541 * compare appropriately to other bookmarks in the meta-dnode. 5542 */ 5543 int 5544 zbookmark_compare(uint16_t dbss1, uint8_t ibs1, uint16_t dbss2, uint8_t ibs2, 5545 const zbookmark_phys_t *zb1, const zbookmark_phys_t *zb2) 5546 { 5547 /* 5548 * These variables represent the "equivalent" values for the zbookmark, 5549 * after converting zbookmarks inside the meta dnode to their 5550 * normal-object equivalents. 5551 */ 5552 uint64_t zb1obj, zb2obj; 5553 uint64_t zb1L0, zb2L0; 5554 uint64_t zb1level, zb2level; 5555 5556 if (zb1->zb_object == zb2->zb_object && 5557 zb1->zb_level == zb2->zb_level && 5558 zb1->zb_blkid == zb2->zb_blkid) 5559 return (0); 5560 5561 IMPLY(zb1->zb_level > 0, ibs1 >= SPA_MINBLOCKSHIFT); 5562 IMPLY(zb2->zb_level > 0, ibs2 >= SPA_MINBLOCKSHIFT); 5563 5564 /* 5565 * BP_SPANB calculates the span in blocks. 5566 */ 5567 zb1L0 = (zb1->zb_blkid) * BP_SPANB(ibs1, zb1->zb_level); 5568 zb2L0 = (zb2->zb_blkid) * BP_SPANB(ibs2, zb2->zb_level); 5569 5570 if (zb1->zb_object == DMU_META_DNODE_OBJECT) { 5571 zb1obj = zb1L0 * (dbss1 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT)); 5572 zb1L0 = 0; 5573 zb1level = zb1->zb_level + COMPARE_META_LEVEL; 5574 } else { 5575 zb1obj = zb1->zb_object; 5576 zb1level = zb1->zb_level; 5577 } 5578 5579 if (zb2->zb_object == DMU_META_DNODE_OBJECT) { 5580 zb2obj = zb2L0 * (dbss2 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT)); 5581 zb2L0 = 0; 5582 zb2level = zb2->zb_level + COMPARE_META_LEVEL; 5583 } else { 5584 zb2obj = zb2->zb_object; 5585 zb2level = zb2->zb_level; 5586 } 5587 5588 /* Now that we have a canonical representation, do the comparison. */ 5589 if (zb1obj != zb2obj) 5590 return (zb1obj < zb2obj ? -1 : 1); 5591 else if (zb1L0 != zb2L0) 5592 return (zb1L0 < zb2L0 ? -1 : 1); 5593 else if (zb1level != zb2level) 5594 return (zb1level > zb2level ? -1 : 1); 5595 /* 5596 * This can (theoretically) happen if the bookmarks have the same object 5597 * and level, but different blkids, if the block sizes are not the same. 5598 * There is presently no way to change the indirect block sizes 5599 */ 5600 return (0); 5601 } 5602 5603 /* 5604 * This function checks the following: given that last_block is the place that 5605 * our traversal stopped last time, does that guarantee that we've visited 5606 * every node under subtree_root? Therefore, we can't just use the raw output 5607 * of zbookmark_compare. We have to pass in a modified version of 5608 * subtree_root; by incrementing the block id, and then checking whether 5609 * last_block is before or equal to that, we can tell whether or not having 5610 * visited last_block implies that all of subtree_root's children have been 5611 * visited. 5612 */ 5613 boolean_t 5614 zbookmark_subtree_completed(const dnode_phys_t *dnp, 5615 const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block) 5616 { 5617 zbookmark_phys_t mod_zb = *subtree_root; 5618 mod_zb.zb_blkid++; 5619 ASSERT0(last_block->zb_level); 5620 5621 /* The objset_phys_t isn't before anything. */ 5622 if (dnp == NULL) 5623 return (B_FALSE); 5624 5625 /* 5626 * We pass in 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT) for the 5627 * data block size in sectors, because that variable is only used if 5628 * the bookmark refers to a block in the meta-dnode. Since we don't 5629 * know without examining it what object it refers to, and there's no 5630 * harm in passing in this value in other cases, we always pass it in. 5631 * 5632 * We pass in 0 for the indirect block size shift because zb2 must be 5633 * level 0. The indirect block size is only used to calculate the span 5634 * of the bookmark, but since the bookmark must be level 0, the span is 5635 * always 1, so the math works out. 5636 * 5637 * If you make changes to how the zbookmark_compare code works, be sure 5638 * to make sure that this code still works afterwards. 5639 */ 5640 return (zbookmark_compare(dnp->dn_datablkszsec, dnp->dn_indblkshift, 5641 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT), 0, &mod_zb, 5642 last_block) <= 0); 5643 } 5644 5645 /* 5646 * This function is similar to zbookmark_subtree_completed(), but returns true 5647 * if subtree_root is equal or ahead of last_block, i.e. still to be done. 5648 */ 5649 boolean_t 5650 zbookmark_subtree_tbd(const dnode_phys_t *dnp, 5651 const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block) 5652 { 5653 ASSERT0(last_block->zb_level); 5654 if (dnp == NULL) 5655 return (B_FALSE); 5656 return (zbookmark_compare(dnp->dn_datablkszsec, dnp->dn_indblkshift, 5657 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT), 0, subtree_root, 5658 last_block) >= 0); 5659 } 5660 5661 EXPORT_SYMBOL(zio_type_name); 5662 EXPORT_SYMBOL(zio_buf_alloc); 5663 EXPORT_SYMBOL(zio_data_buf_alloc); 5664 EXPORT_SYMBOL(zio_buf_free); 5665 EXPORT_SYMBOL(zio_data_buf_free); 5666 5667 ZFS_MODULE_PARAM(zfs_zio, zio_, slow_io_ms, INT, ZMOD_RW, 5668 "Max I/O completion time (milliseconds) before marking it as slow"); 5669 5670 ZFS_MODULE_PARAM(zfs_zio, zio_, requeue_io_start_cut_in_line, INT, ZMOD_RW, 5671 "Prioritize requeued I/O"); 5672 5673 ZFS_MODULE_PARAM(zfs, zfs_, sync_pass_deferred_free, UINT, ZMOD_RW, 5674 "Defer frees starting in this pass"); 5675 5676 ZFS_MODULE_PARAM(zfs, zfs_, sync_pass_dont_compress, UINT, ZMOD_RW, 5677 "Don't compress starting in this pass"); 5678 5679 ZFS_MODULE_PARAM(zfs, zfs_, sync_pass_rewrite, UINT, ZMOD_RW, 5680 "Rewrite new bps starting in this pass"); 5681 5682 ZFS_MODULE_PARAM(zfs_zio, zio_, dva_throttle_enabled, INT, ZMOD_RW, 5683 "Throttle block allocations in the ZIO pipeline"); 5684 5685 ZFS_MODULE_PARAM(zfs_zio, zio_, deadman_log_all, INT, ZMOD_RW, 5686 "Log all slow ZIOs, not just those with vdevs"); 5687