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