1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2017 by Delphix. All rights reserved. 24 * Copyright (c) 2014 Integros [integros.com] 25 */ 26 27 /* Portions Copyright 2010 Robert Milkowski */ 28 29 #include <sys/zfs_context.h> 30 #include <sys/spa.h> 31 #include <sys/dmu.h> 32 #include <sys/zap.h> 33 #include <sys/arc.h> 34 #include <sys/stat.h> 35 #include <sys/resource.h> 36 #include <sys/zil.h> 37 #include <sys/zil_impl.h> 38 #include <sys/dsl_dataset.h> 39 #include <sys/vdev_impl.h> 40 #include <sys/dmu_tx.h> 41 #include <sys/dsl_pool.h> 42 #include <sys/abd.h> 43 44 /* 45 * The zfs intent log (ZIL) saves transaction records of system calls 46 * that change the file system in memory with enough information 47 * to be able to replay them. These are stored in memory until 48 * either the DMU transaction group (txg) commits them to the stable pool 49 * and they can be discarded, or they are flushed to the stable log 50 * (also in the pool) due to a fsync, O_DSYNC or other synchronous 51 * requirement. In the event of a panic or power fail then those log 52 * records (transactions) are replayed. 53 * 54 * There is one ZIL per file system. Its on-disk (pool) format consists 55 * of 3 parts: 56 * 57 * - ZIL header 58 * - ZIL blocks 59 * - ZIL records 60 * 61 * A log record holds a system call transaction. Log blocks can 62 * hold many log records and the blocks are chained together. 63 * Each ZIL block contains a block pointer (blkptr_t) to the next 64 * ZIL block in the chain. The ZIL header points to the first 65 * block in the chain. Note there is not a fixed place in the pool 66 * to hold blocks. They are dynamically allocated and freed as 67 * needed from the blocks available. Figure X shows the ZIL structure: 68 */ 69 70 /* 71 * Disable intent logging replay. This global ZIL switch affects all pools. 72 */ 73 int zil_replay_disable = 0; 74 75 /* 76 * Tunable parameter for debugging or performance analysis. Setting 77 * zfs_nocacheflush will cause corruption on power loss if a volatile 78 * out-of-order write cache is enabled. 79 */ 80 boolean_t zfs_nocacheflush = B_FALSE; 81 82 static kmem_cache_t *zil_lwb_cache; 83 84 static void zil_async_to_sync(zilog_t *zilog, uint64_t foid); 85 86 #define LWB_EMPTY(lwb) ((BP_GET_LSIZE(&lwb->lwb_blk) - \ 87 sizeof (zil_chain_t)) == (lwb->lwb_sz - lwb->lwb_nused)) 88 89 static int 90 zil_bp_compare(const void *x1, const void *x2) 91 { 92 const dva_t *dva1 = &((zil_bp_node_t *)x1)->zn_dva; 93 const dva_t *dva2 = &((zil_bp_node_t *)x2)->zn_dva; 94 95 if (DVA_GET_VDEV(dva1) < DVA_GET_VDEV(dva2)) 96 return (-1); 97 if (DVA_GET_VDEV(dva1) > DVA_GET_VDEV(dva2)) 98 return (1); 99 100 if (DVA_GET_OFFSET(dva1) < DVA_GET_OFFSET(dva2)) 101 return (-1); 102 if (DVA_GET_OFFSET(dva1) > DVA_GET_OFFSET(dva2)) 103 return (1); 104 105 return (0); 106 } 107 108 static void 109 zil_bp_tree_init(zilog_t *zilog) 110 { 111 avl_create(&zilog->zl_bp_tree, zil_bp_compare, 112 sizeof (zil_bp_node_t), offsetof(zil_bp_node_t, zn_node)); 113 } 114 115 static void 116 zil_bp_tree_fini(zilog_t *zilog) 117 { 118 avl_tree_t *t = &zilog->zl_bp_tree; 119 zil_bp_node_t *zn; 120 void *cookie = NULL; 121 122 while ((zn = avl_destroy_nodes(t, &cookie)) != NULL) 123 kmem_free(zn, sizeof (zil_bp_node_t)); 124 125 avl_destroy(t); 126 } 127 128 int 129 zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp) 130 { 131 avl_tree_t *t = &zilog->zl_bp_tree; 132 const dva_t *dva; 133 zil_bp_node_t *zn; 134 avl_index_t where; 135 136 if (BP_IS_EMBEDDED(bp)) 137 return (0); 138 139 dva = BP_IDENTITY(bp); 140 141 if (avl_find(t, dva, &where) != NULL) 142 return (SET_ERROR(EEXIST)); 143 144 zn = kmem_alloc(sizeof (zil_bp_node_t), KM_SLEEP); 145 zn->zn_dva = *dva; 146 avl_insert(t, zn, where); 147 148 return (0); 149 } 150 151 static zil_header_t * 152 zil_header_in_syncing_context(zilog_t *zilog) 153 { 154 return ((zil_header_t *)zilog->zl_header); 155 } 156 157 static void 158 zil_init_log_chain(zilog_t *zilog, blkptr_t *bp) 159 { 160 zio_cksum_t *zc = &bp->blk_cksum; 161 162 zc->zc_word[ZIL_ZC_GUID_0] = spa_get_random(-1ULL); 163 zc->zc_word[ZIL_ZC_GUID_1] = spa_get_random(-1ULL); 164 zc->zc_word[ZIL_ZC_OBJSET] = dmu_objset_id(zilog->zl_os); 165 zc->zc_word[ZIL_ZC_SEQ] = 1ULL; 166 } 167 168 /* 169 * Read a log block and make sure it's valid. 170 */ 171 static int 172 zil_read_log_block(zilog_t *zilog, const blkptr_t *bp, blkptr_t *nbp, void *dst, 173 char **end) 174 { 175 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 176 arc_flags_t aflags = ARC_FLAG_WAIT; 177 arc_buf_t *abuf = NULL; 178 zbookmark_phys_t zb; 179 int error; 180 181 if (zilog->zl_header->zh_claim_txg == 0) 182 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 183 184 if (!(zilog->zl_header->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 185 zio_flags |= ZIO_FLAG_SPECULATIVE; 186 187 SET_BOOKMARK(&zb, bp->blk_cksum.zc_word[ZIL_ZC_OBJSET], 188 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); 189 190 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 191 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 192 193 if (error == 0) { 194 zio_cksum_t cksum = bp->blk_cksum; 195 196 /* 197 * Validate the checksummed log block. 198 * 199 * Sequence numbers should be... sequential. The checksum 200 * verifier for the next block should be bp's checksum plus 1. 201 * 202 * Also check the log chain linkage and size used. 203 */ 204 cksum.zc_word[ZIL_ZC_SEQ]++; 205 206 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 207 zil_chain_t *zilc = abuf->b_data; 208 char *lr = (char *)(zilc + 1); 209 uint64_t len = zilc->zc_nused - sizeof (zil_chain_t); 210 211 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 212 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk)) { 213 error = SET_ERROR(ECKSUM); 214 } else { 215 ASSERT3U(len, <=, SPA_OLD_MAXBLOCKSIZE); 216 bcopy(lr, dst, len); 217 *end = (char *)dst + len; 218 *nbp = zilc->zc_next_blk; 219 } 220 } else { 221 char *lr = abuf->b_data; 222 uint64_t size = BP_GET_LSIZE(bp); 223 zil_chain_t *zilc = (zil_chain_t *)(lr + size) - 1; 224 225 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 226 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk) || 227 (zilc->zc_nused > (size - sizeof (*zilc)))) { 228 error = SET_ERROR(ECKSUM); 229 } else { 230 ASSERT3U(zilc->zc_nused, <=, 231 SPA_OLD_MAXBLOCKSIZE); 232 bcopy(lr, dst, zilc->zc_nused); 233 *end = (char *)dst + zilc->zc_nused; 234 *nbp = zilc->zc_next_blk; 235 } 236 } 237 238 arc_buf_destroy(abuf, &abuf); 239 } 240 241 return (error); 242 } 243 244 /* 245 * Read a TX_WRITE log data block. 246 */ 247 static int 248 zil_read_log_data(zilog_t *zilog, const lr_write_t *lr, void *wbuf) 249 { 250 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 251 const blkptr_t *bp = &lr->lr_blkptr; 252 arc_flags_t aflags = ARC_FLAG_WAIT; 253 arc_buf_t *abuf = NULL; 254 zbookmark_phys_t zb; 255 int error; 256 257 if (BP_IS_HOLE(bp)) { 258 if (wbuf != NULL) 259 bzero(wbuf, MAX(BP_GET_LSIZE(bp), lr->lr_length)); 260 return (0); 261 } 262 263 if (zilog->zl_header->zh_claim_txg == 0) 264 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 265 266 SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os), lr->lr_foid, 267 ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp)); 268 269 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 270 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 271 272 if (error == 0) { 273 if (wbuf != NULL) 274 bcopy(abuf->b_data, wbuf, arc_buf_size(abuf)); 275 arc_buf_destroy(abuf, &abuf); 276 } 277 278 return (error); 279 } 280 281 /* 282 * Parse the intent log, and call parse_func for each valid record within. 283 */ 284 int 285 zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func, 286 zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg) 287 { 288 const zil_header_t *zh = zilog->zl_header; 289 boolean_t claimed = !!zh->zh_claim_txg; 290 uint64_t claim_blk_seq = claimed ? zh->zh_claim_blk_seq : UINT64_MAX; 291 uint64_t claim_lr_seq = claimed ? zh->zh_claim_lr_seq : UINT64_MAX; 292 uint64_t max_blk_seq = 0; 293 uint64_t max_lr_seq = 0; 294 uint64_t blk_count = 0; 295 uint64_t lr_count = 0; 296 blkptr_t blk, next_blk; 297 char *lrbuf, *lrp; 298 int error = 0; 299 300 /* 301 * Old logs didn't record the maximum zh_claim_lr_seq. 302 */ 303 if (!(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 304 claim_lr_seq = UINT64_MAX; 305 306 /* 307 * Starting at the block pointed to by zh_log we read the log chain. 308 * For each block in the chain we strongly check that block to 309 * ensure its validity. We stop when an invalid block is found. 310 * For each block pointer in the chain we call parse_blk_func(). 311 * For each record in each valid block we call parse_lr_func(). 312 * If the log has been claimed, stop if we encounter a sequence 313 * number greater than the highest claimed sequence number. 314 */ 315 lrbuf = zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE); 316 zil_bp_tree_init(zilog); 317 318 for (blk = zh->zh_log; !BP_IS_HOLE(&blk); blk = next_blk) { 319 uint64_t blk_seq = blk.blk_cksum.zc_word[ZIL_ZC_SEQ]; 320 int reclen; 321 char *end; 322 323 if (blk_seq > claim_blk_seq) 324 break; 325 if ((error = parse_blk_func(zilog, &blk, arg, txg)) != 0) 326 break; 327 ASSERT3U(max_blk_seq, <, blk_seq); 328 max_blk_seq = blk_seq; 329 blk_count++; 330 331 if (max_lr_seq == claim_lr_seq && max_blk_seq == claim_blk_seq) 332 break; 333 334 error = zil_read_log_block(zilog, &blk, &next_blk, lrbuf, &end); 335 if (error != 0) 336 break; 337 338 for (lrp = lrbuf; lrp < end; lrp += reclen) { 339 lr_t *lr = (lr_t *)lrp; 340 reclen = lr->lrc_reclen; 341 ASSERT3U(reclen, >=, sizeof (lr_t)); 342 if (lr->lrc_seq > claim_lr_seq) 343 goto done; 344 if ((error = parse_lr_func(zilog, lr, arg, txg)) != 0) 345 goto done; 346 ASSERT3U(max_lr_seq, <, lr->lrc_seq); 347 max_lr_seq = lr->lrc_seq; 348 lr_count++; 349 } 350 } 351 done: 352 zilog->zl_parse_error = error; 353 zilog->zl_parse_blk_seq = max_blk_seq; 354 zilog->zl_parse_lr_seq = max_lr_seq; 355 zilog->zl_parse_blk_count = blk_count; 356 zilog->zl_parse_lr_count = lr_count; 357 358 ASSERT(!claimed || !(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID) || 359 (max_blk_seq == claim_blk_seq && max_lr_seq == claim_lr_seq)); 360 361 zil_bp_tree_fini(zilog); 362 zio_buf_free(lrbuf, SPA_OLD_MAXBLOCKSIZE); 363 364 return (error); 365 } 366 367 static int 368 zil_claim_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t first_txg) 369 { 370 /* 371 * Claim log block if not already committed and not already claimed. 372 * If tx == NULL, just verify that the block is claimable. 373 */ 374 if (BP_IS_HOLE(bp) || bp->blk_birth < first_txg || 375 zil_bp_tree_add(zilog, bp) != 0) 376 return (0); 377 378 return (zio_wait(zio_claim(NULL, zilog->zl_spa, 379 tx == NULL ? 0 : first_txg, bp, spa_claim_notify, NULL, 380 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB))); 381 } 382 383 static int 384 zil_claim_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t first_txg) 385 { 386 lr_write_t *lr = (lr_write_t *)lrc; 387 int error; 388 389 if (lrc->lrc_txtype != TX_WRITE) 390 return (0); 391 392 /* 393 * If the block is not readable, don't claim it. This can happen 394 * in normal operation when a log block is written to disk before 395 * some of the dmu_sync() blocks it points to. In this case, the 396 * transaction cannot have been committed to anyone (we would have 397 * waited for all writes to be stable first), so it is semantically 398 * correct to declare this the end of the log. 399 */ 400 if (lr->lr_blkptr.blk_birth >= first_txg && 401 (error = zil_read_log_data(zilog, lr, NULL)) != 0) 402 return (error); 403 return (zil_claim_log_block(zilog, &lr->lr_blkptr, tx, first_txg)); 404 } 405 406 /* ARGSUSED */ 407 static int 408 zil_free_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t claim_txg) 409 { 410 zio_free_zil(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 411 412 return (0); 413 } 414 415 static int 416 zil_free_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t claim_txg) 417 { 418 lr_write_t *lr = (lr_write_t *)lrc; 419 blkptr_t *bp = &lr->lr_blkptr; 420 421 /* 422 * If we previously claimed it, we need to free it. 423 */ 424 if (claim_txg != 0 && lrc->lrc_txtype == TX_WRITE && 425 bp->blk_birth >= claim_txg && zil_bp_tree_add(zilog, bp) == 0 && 426 !BP_IS_HOLE(bp)) 427 zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 428 429 return (0); 430 } 431 432 static lwb_t * 433 zil_alloc_lwb(zilog_t *zilog, blkptr_t *bp, uint64_t txg) 434 { 435 lwb_t *lwb; 436 437 lwb = kmem_cache_alloc(zil_lwb_cache, KM_SLEEP); 438 lwb->lwb_zilog = zilog; 439 lwb->lwb_blk = *bp; 440 lwb->lwb_buf = zio_buf_alloc(BP_GET_LSIZE(bp)); 441 lwb->lwb_max_txg = txg; 442 lwb->lwb_zio = NULL; 443 lwb->lwb_tx = NULL; 444 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 445 lwb->lwb_nused = sizeof (zil_chain_t); 446 lwb->lwb_sz = BP_GET_LSIZE(bp); 447 } else { 448 lwb->lwb_nused = 0; 449 lwb->lwb_sz = BP_GET_LSIZE(bp) - sizeof (zil_chain_t); 450 } 451 452 mutex_enter(&zilog->zl_lock); 453 list_insert_tail(&zilog->zl_lwb_list, lwb); 454 mutex_exit(&zilog->zl_lock); 455 456 return (lwb); 457 } 458 459 /* 460 * Called when we create in-memory log transactions so that we know 461 * to cleanup the itxs at the end of spa_sync(). 462 */ 463 void 464 zilog_dirty(zilog_t *zilog, uint64_t txg) 465 { 466 dsl_pool_t *dp = zilog->zl_dmu_pool; 467 dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); 468 469 if (ds->ds_is_snapshot) 470 panic("dirtying snapshot!"); 471 472 if (txg_list_add(&dp->dp_dirty_zilogs, zilog, txg)) { 473 /* up the hold count until we can be written out */ 474 dmu_buf_add_ref(ds->ds_dbuf, zilog); 475 } 476 } 477 478 /* 479 * Determine if the zil is dirty in the specified txg. Callers wanting to 480 * ensure that the dirty state does not change must hold the itxg_lock for 481 * the specified txg. Holding the lock will ensure that the zil cannot be 482 * dirtied (zil_itx_assign) or cleaned (zil_clean) while we check its current 483 * state. 484 */ 485 boolean_t 486 zilog_is_dirty_in_txg(zilog_t *zilog, uint64_t txg) 487 { 488 dsl_pool_t *dp = zilog->zl_dmu_pool; 489 490 if (txg_list_member(&dp->dp_dirty_zilogs, zilog, txg & TXG_MASK)) 491 return (B_TRUE); 492 return (B_FALSE); 493 } 494 495 /* 496 * Determine if the zil is dirty. The zil is considered dirty if it has 497 * any pending itx records that have not been cleaned by zil_clean(). 498 */ 499 boolean_t 500 zilog_is_dirty(zilog_t *zilog) 501 { 502 dsl_pool_t *dp = zilog->zl_dmu_pool; 503 504 for (int t = 0; t < TXG_SIZE; t++) { 505 if (txg_list_member(&dp->dp_dirty_zilogs, zilog, t)) 506 return (B_TRUE); 507 } 508 return (B_FALSE); 509 } 510 511 /* 512 * Create an on-disk intent log. 513 */ 514 static lwb_t * 515 zil_create(zilog_t *zilog) 516 { 517 const zil_header_t *zh = zilog->zl_header; 518 lwb_t *lwb = NULL; 519 uint64_t txg = 0; 520 dmu_tx_t *tx = NULL; 521 blkptr_t blk; 522 int error = 0; 523 524 /* 525 * Wait for any previous destroy to complete. 526 */ 527 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 528 529 ASSERT(zh->zh_claim_txg == 0); 530 ASSERT(zh->zh_replay_seq == 0); 531 532 blk = zh->zh_log; 533 534 /* 535 * Allocate an initial log block if: 536 * - there isn't one already 537 * - the existing block is the wrong endianess 538 */ 539 if (BP_IS_HOLE(&blk) || BP_SHOULD_BYTESWAP(&blk)) { 540 tx = dmu_tx_create(zilog->zl_os); 541 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 542 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 543 txg = dmu_tx_get_txg(tx); 544 545 if (!BP_IS_HOLE(&blk)) { 546 zio_free_zil(zilog->zl_spa, txg, &blk); 547 BP_ZERO(&blk); 548 } 549 550 error = zio_alloc_zil(zilog->zl_spa, txg, &blk, NULL, 551 ZIL_MIN_BLKSZ, zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 552 553 if (error == 0) 554 zil_init_log_chain(zilog, &blk); 555 } 556 557 /* 558 * Allocate a log write buffer (lwb) for the first log block. 559 */ 560 if (error == 0) 561 lwb = zil_alloc_lwb(zilog, &blk, txg); 562 563 /* 564 * If we just allocated the first log block, commit our transaction 565 * and wait for zil_sync() to stuff the block poiner into zh_log. 566 * (zh is part of the MOS, so we cannot modify it in open context.) 567 */ 568 if (tx != NULL) { 569 dmu_tx_commit(tx); 570 txg_wait_synced(zilog->zl_dmu_pool, txg); 571 } 572 573 ASSERT(bcmp(&blk, &zh->zh_log, sizeof (blk)) == 0); 574 575 return (lwb); 576 } 577 578 /* 579 * In one tx, free all log blocks and clear the log header. 580 * If keep_first is set, then we're replaying a log with no content. 581 * We want to keep the first block, however, so that the first 582 * synchronous transaction doesn't require a txg_wait_synced() 583 * in zil_create(). We don't need to txg_wait_synced() here either 584 * when keep_first is set, because both zil_create() and zil_destroy() 585 * will wait for any in-progress destroys to complete. 586 */ 587 void 588 zil_destroy(zilog_t *zilog, boolean_t keep_first) 589 { 590 const zil_header_t *zh = zilog->zl_header; 591 lwb_t *lwb; 592 dmu_tx_t *tx; 593 uint64_t txg; 594 595 /* 596 * Wait for any previous destroy to complete. 597 */ 598 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 599 600 zilog->zl_old_header = *zh; /* debugging aid */ 601 602 if (BP_IS_HOLE(&zh->zh_log)) 603 return; 604 605 tx = dmu_tx_create(zilog->zl_os); 606 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 607 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 608 txg = dmu_tx_get_txg(tx); 609 610 mutex_enter(&zilog->zl_lock); 611 612 ASSERT3U(zilog->zl_destroy_txg, <, txg); 613 zilog->zl_destroy_txg = txg; 614 zilog->zl_keep_first = keep_first; 615 616 if (!list_is_empty(&zilog->zl_lwb_list)) { 617 ASSERT(zh->zh_claim_txg == 0); 618 VERIFY(!keep_first); 619 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 620 list_remove(&zilog->zl_lwb_list, lwb); 621 if (lwb->lwb_buf != NULL) 622 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 623 zio_free_zil(zilog->zl_spa, txg, &lwb->lwb_blk); 624 kmem_cache_free(zil_lwb_cache, lwb); 625 } 626 } else if (!keep_first) { 627 zil_destroy_sync(zilog, tx); 628 } 629 mutex_exit(&zilog->zl_lock); 630 631 dmu_tx_commit(tx); 632 } 633 634 void 635 zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx) 636 { 637 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 638 (void) zil_parse(zilog, zil_free_log_block, 639 zil_free_log_record, tx, zilog->zl_header->zh_claim_txg); 640 } 641 642 int 643 zil_claim(dsl_pool_t *dp, dsl_dataset_t *ds, void *txarg) 644 { 645 dmu_tx_t *tx = txarg; 646 uint64_t first_txg = dmu_tx_get_txg(tx); 647 zilog_t *zilog; 648 zil_header_t *zh; 649 objset_t *os; 650 int error; 651 652 error = dmu_objset_own_obj(dp, ds->ds_object, 653 DMU_OST_ANY, B_FALSE, FTAG, &os); 654 if (error != 0) { 655 /* 656 * EBUSY indicates that the objset is inconsistent, in which 657 * case it can not have a ZIL. 658 */ 659 if (error != EBUSY) { 660 cmn_err(CE_WARN, "can't open objset for %llu, error %u", 661 (unsigned long long)ds->ds_object, error); 662 } 663 return (0); 664 } 665 666 zilog = dmu_objset_zil(os); 667 zh = zil_header_in_syncing_context(zilog); 668 669 if (spa_get_log_state(zilog->zl_spa) == SPA_LOG_CLEAR) { 670 if (!BP_IS_HOLE(&zh->zh_log)) 671 zio_free_zil(zilog->zl_spa, first_txg, &zh->zh_log); 672 BP_ZERO(&zh->zh_log); 673 dsl_dataset_dirty(dmu_objset_ds(os), tx); 674 dmu_objset_disown(os, FTAG); 675 return (0); 676 } 677 678 /* 679 * Claim all log blocks if we haven't already done so, and remember 680 * the highest claimed sequence number. This ensures that if we can 681 * read only part of the log now (e.g. due to a missing device), 682 * but we can read the entire log later, we will not try to replay 683 * or destroy beyond the last block we successfully claimed. 684 */ 685 ASSERT3U(zh->zh_claim_txg, <=, first_txg); 686 if (zh->zh_claim_txg == 0 && !BP_IS_HOLE(&zh->zh_log)) { 687 (void) zil_parse(zilog, zil_claim_log_block, 688 zil_claim_log_record, tx, first_txg); 689 zh->zh_claim_txg = first_txg; 690 zh->zh_claim_blk_seq = zilog->zl_parse_blk_seq; 691 zh->zh_claim_lr_seq = zilog->zl_parse_lr_seq; 692 if (zilog->zl_parse_lr_count || zilog->zl_parse_blk_count > 1) 693 zh->zh_flags |= ZIL_REPLAY_NEEDED; 694 zh->zh_flags |= ZIL_CLAIM_LR_SEQ_VALID; 695 dsl_dataset_dirty(dmu_objset_ds(os), tx); 696 } 697 698 ASSERT3U(first_txg, ==, (spa_last_synced_txg(zilog->zl_spa) + 1)); 699 dmu_objset_disown(os, FTAG); 700 return (0); 701 } 702 703 /* 704 * Check the log by walking the log chain. 705 * Checksum errors are ok as they indicate the end of the chain. 706 * Any other error (no device or read failure) returns an error. 707 */ 708 /* ARGSUSED */ 709 int 710 zil_check_log_chain(dsl_pool_t *dp, dsl_dataset_t *ds, void *tx) 711 { 712 zilog_t *zilog; 713 objset_t *os; 714 blkptr_t *bp; 715 int error; 716 717 ASSERT(tx == NULL); 718 719 error = dmu_objset_from_ds(ds, &os); 720 if (error != 0) { 721 cmn_err(CE_WARN, "can't open objset %llu, error %d", 722 (unsigned long long)ds->ds_object, error); 723 return (0); 724 } 725 726 zilog = dmu_objset_zil(os); 727 bp = (blkptr_t *)&zilog->zl_header->zh_log; 728 729 /* 730 * Check the first block and determine if it's on a log device 731 * which may have been removed or faulted prior to loading this 732 * pool. If so, there's no point in checking the rest of the log 733 * as its content should have already been synced to the pool. 734 */ 735 if (!BP_IS_HOLE(bp)) { 736 vdev_t *vd; 737 boolean_t valid = B_TRUE; 738 739 spa_config_enter(os->os_spa, SCL_STATE, FTAG, RW_READER); 740 vd = vdev_lookup_top(os->os_spa, DVA_GET_VDEV(&bp->blk_dva[0])); 741 if (vd->vdev_islog && vdev_is_dead(vd)) 742 valid = vdev_log_state_valid(vd); 743 spa_config_exit(os->os_spa, SCL_STATE, FTAG); 744 745 if (!valid) 746 return (0); 747 } 748 749 /* 750 * Because tx == NULL, zil_claim_log_block() will not actually claim 751 * any blocks, but just determine whether it is possible to do so. 752 * In addition to checking the log chain, zil_claim_log_block() 753 * will invoke zio_claim() with a done func of spa_claim_notify(), 754 * which will update spa_max_claim_txg. See spa_load() for details. 755 */ 756 error = zil_parse(zilog, zil_claim_log_block, zil_claim_log_record, tx, 757 zilog->zl_header->zh_claim_txg ? -1ULL : spa_first_txg(os->os_spa)); 758 759 return ((error == ECKSUM || error == ENOENT) ? 0 : error); 760 } 761 762 static int 763 zil_vdev_compare(const void *x1, const void *x2) 764 { 765 const uint64_t v1 = ((zil_vdev_node_t *)x1)->zv_vdev; 766 const uint64_t v2 = ((zil_vdev_node_t *)x2)->zv_vdev; 767 768 if (v1 < v2) 769 return (-1); 770 if (v1 > v2) 771 return (1); 772 773 return (0); 774 } 775 776 void 777 zil_add_block(zilog_t *zilog, const blkptr_t *bp) 778 { 779 avl_tree_t *t = &zilog->zl_vdev_tree; 780 avl_index_t where; 781 zil_vdev_node_t *zv, zvsearch; 782 int ndvas = BP_GET_NDVAS(bp); 783 int i; 784 785 if (zfs_nocacheflush) 786 return; 787 788 ASSERT(zilog->zl_writer); 789 790 /* 791 * Even though we're zl_writer, we still need a lock because the 792 * zl_get_data() callbacks may have dmu_sync() done callbacks 793 * that will run concurrently. 794 */ 795 mutex_enter(&zilog->zl_vdev_lock); 796 for (i = 0; i < ndvas; i++) { 797 zvsearch.zv_vdev = DVA_GET_VDEV(&bp->blk_dva[i]); 798 if (avl_find(t, &zvsearch, &where) == NULL) { 799 zv = kmem_alloc(sizeof (*zv), KM_SLEEP); 800 zv->zv_vdev = zvsearch.zv_vdev; 801 avl_insert(t, zv, where); 802 } 803 } 804 mutex_exit(&zilog->zl_vdev_lock); 805 } 806 807 static void 808 zil_flush_vdevs(zilog_t *zilog) 809 { 810 spa_t *spa = zilog->zl_spa; 811 avl_tree_t *t = &zilog->zl_vdev_tree; 812 void *cookie = NULL; 813 zil_vdev_node_t *zv; 814 zio_t *zio; 815 816 ASSERT(zilog->zl_writer); 817 818 /* 819 * We don't need zl_vdev_lock here because we're the zl_writer, 820 * and all zl_get_data() callbacks are done. 821 */ 822 if (avl_numnodes(t) == 0) 823 return; 824 825 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 826 827 zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL); 828 829 while ((zv = avl_destroy_nodes(t, &cookie)) != NULL) { 830 vdev_t *vd = vdev_lookup_top(spa, zv->zv_vdev); 831 if (vd != NULL) 832 zio_flush(zio, vd); 833 kmem_free(zv, sizeof (*zv)); 834 } 835 836 /* 837 * Wait for all the flushes to complete. Not all devices actually 838 * support the DKIOCFLUSHWRITECACHE ioctl, so it's OK if it fails. 839 */ 840 (void) zio_wait(zio); 841 842 spa_config_exit(spa, SCL_STATE, FTAG); 843 } 844 845 /* 846 * Function called when a log block write completes 847 */ 848 static void 849 zil_lwb_write_done(zio_t *zio) 850 { 851 lwb_t *lwb = zio->io_private; 852 zilog_t *zilog = lwb->lwb_zilog; 853 dmu_tx_t *tx = lwb->lwb_tx; 854 855 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); 856 ASSERT(BP_GET_TYPE(zio->io_bp) == DMU_OT_INTENT_LOG); 857 ASSERT(BP_GET_LEVEL(zio->io_bp) == 0); 858 ASSERT(BP_GET_BYTEORDER(zio->io_bp) == ZFS_HOST_BYTEORDER); 859 ASSERT(!BP_IS_GANG(zio->io_bp)); 860 ASSERT(!BP_IS_HOLE(zio->io_bp)); 861 ASSERT(BP_GET_FILL(zio->io_bp) == 0); 862 863 /* 864 * Ensure the lwb buffer pointer is cleared before releasing 865 * the txg. If we have had an allocation failure and 866 * the txg is waiting to sync then we want want zil_sync() 867 * to remove the lwb so that it's not picked up as the next new 868 * one in zil_commit_writer(). zil_sync() will only remove 869 * the lwb if lwb_buf is null. 870 */ 871 abd_put(zio->io_abd); 872 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 873 mutex_enter(&zilog->zl_lock); 874 lwb->lwb_buf = NULL; 875 lwb->lwb_tx = NULL; 876 mutex_exit(&zilog->zl_lock); 877 878 /* 879 * Now that we've written this log block, we have a stable pointer 880 * to the next block in the chain, so it's OK to let the txg in 881 * which we allocated the next block sync. 882 */ 883 dmu_tx_commit(tx); 884 } 885 886 /* 887 * Initialize the io for a log block. 888 */ 889 static void 890 zil_lwb_write_init(zilog_t *zilog, lwb_t *lwb) 891 { 892 zbookmark_phys_t zb; 893 894 SET_BOOKMARK(&zb, lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_OBJSET], 895 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, 896 lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_SEQ]); 897 898 if (zilog->zl_root_zio == NULL) { 899 zilog->zl_root_zio = zio_root(zilog->zl_spa, NULL, NULL, 900 ZIO_FLAG_CANFAIL); 901 } 902 if (lwb->lwb_zio == NULL) { 903 abd_t *lwb_abd = abd_get_from_buf(lwb->lwb_buf, 904 BP_GET_LSIZE(&lwb->lwb_blk)); 905 lwb->lwb_zio = zio_rewrite(zilog->zl_root_zio, zilog->zl_spa, 906 0, &lwb->lwb_blk, lwb_abd, BP_GET_LSIZE(&lwb->lwb_blk), 907 zil_lwb_write_done, lwb, ZIO_PRIORITY_SYNC_WRITE, 908 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE, &zb); 909 } 910 } 911 912 /* 913 * Define a limited set of intent log block sizes. 914 * 915 * These must be a multiple of 4KB. Note only the amount used (again 916 * aligned to 4KB) actually gets written. However, we can't always just 917 * allocate SPA_OLD_MAXBLOCKSIZE as the slog space could be exhausted. 918 */ 919 uint64_t zil_block_buckets[] = { 920 4096, /* non TX_WRITE */ 921 8192+4096, /* data base */ 922 32*1024 + 4096, /* NFS writes */ 923 UINT64_MAX 924 }; 925 926 /* 927 * Use the slog as long as the logbias is 'latency' and the current commit size 928 * is less than the limit or the total list size is less than 2X the limit. 929 * Limit checking is disabled by setting zil_slog_limit to UINT64_MAX. 930 */ 931 uint64_t zil_slog_limit = 1024 * 1024; 932 #define USE_SLOG(zilog) (((zilog)->zl_logbias == ZFS_LOGBIAS_LATENCY) && \ 933 (((zilog)->zl_cur_used < zil_slog_limit) || \ 934 ((zilog)->zl_itx_list_sz < (zil_slog_limit << 1)))) 935 936 /* 937 * Start a log block write and advance to the next log block. 938 * Calls are serialized. 939 */ 940 static lwb_t * 941 zil_lwb_write_start(zilog_t *zilog, lwb_t *lwb) 942 { 943 lwb_t *nlwb = NULL; 944 zil_chain_t *zilc; 945 spa_t *spa = zilog->zl_spa; 946 blkptr_t *bp; 947 dmu_tx_t *tx; 948 uint64_t txg; 949 uint64_t zil_blksz, wsz; 950 int i, error; 951 952 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 953 zilc = (zil_chain_t *)lwb->lwb_buf; 954 bp = &zilc->zc_next_blk; 955 } else { 956 zilc = (zil_chain_t *)(lwb->lwb_buf + lwb->lwb_sz); 957 bp = &zilc->zc_next_blk; 958 } 959 960 ASSERT(lwb->lwb_nused <= lwb->lwb_sz); 961 962 /* 963 * Allocate the next block and save its address in this block 964 * before writing it in order to establish the log chain. 965 * Note that if the allocation of nlwb synced before we wrote 966 * the block that points at it (lwb), we'd leak it if we crashed. 967 * Therefore, we don't do dmu_tx_commit() until zil_lwb_write_done(). 968 * We dirty the dataset to ensure that zil_sync() will be called 969 * to clean up in the event of allocation failure or I/O failure. 970 */ 971 tx = dmu_tx_create(zilog->zl_os); 972 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 973 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 974 txg = dmu_tx_get_txg(tx); 975 976 lwb->lwb_tx = tx; 977 978 /* 979 * Log blocks are pre-allocated. Here we select the size of the next 980 * block, based on size used in the last block. 981 * - first find the smallest bucket that will fit the block from a 982 * limited set of block sizes. This is because it's faster to write 983 * blocks allocated from the same metaslab as they are adjacent or 984 * close. 985 * - next find the maximum from the new suggested size and an array of 986 * previous sizes. This lessens a picket fence effect of wrongly 987 * guesssing the size if we have a stream of say 2k, 64k, 2k, 64k 988 * requests. 989 * 990 * Note we only write what is used, but we can't just allocate 991 * the maximum block size because we can exhaust the available 992 * pool log space. 993 */ 994 zil_blksz = zilog->zl_cur_used + sizeof (zil_chain_t); 995 for (i = 0; zil_blksz > zil_block_buckets[i]; i++) 996 continue; 997 zil_blksz = zil_block_buckets[i]; 998 if (zil_blksz == UINT64_MAX) 999 zil_blksz = SPA_OLD_MAXBLOCKSIZE; 1000 zilog->zl_prev_blks[zilog->zl_prev_rotor] = zil_blksz; 1001 for (i = 0; i < ZIL_PREV_BLKS; i++) 1002 zil_blksz = MAX(zil_blksz, zilog->zl_prev_blks[i]); 1003 zilog->zl_prev_rotor = (zilog->zl_prev_rotor + 1) & (ZIL_PREV_BLKS - 1); 1004 1005 BP_ZERO(bp); 1006 /* pass the old blkptr in order to spread log blocks across devs */ 1007 error = zio_alloc_zil(spa, txg, bp, &lwb->lwb_blk, zil_blksz, 1008 USE_SLOG(zilog)); 1009 if (error == 0) { 1010 ASSERT3U(bp->blk_birth, ==, txg); 1011 bp->blk_cksum = lwb->lwb_blk.blk_cksum; 1012 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]++; 1013 1014 /* 1015 * Allocate a new log write buffer (lwb). 1016 */ 1017 nlwb = zil_alloc_lwb(zilog, bp, txg); 1018 1019 /* Record the block for later vdev flushing */ 1020 zil_add_block(zilog, &lwb->lwb_blk); 1021 } 1022 1023 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 1024 /* For Slim ZIL only write what is used. */ 1025 wsz = P2ROUNDUP_TYPED(lwb->lwb_nused, ZIL_MIN_BLKSZ, uint64_t); 1026 ASSERT3U(wsz, <=, lwb->lwb_sz); 1027 zio_shrink(lwb->lwb_zio, wsz); 1028 1029 } else { 1030 wsz = lwb->lwb_sz; 1031 } 1032 1033 zilc->zc_pad = 0; 1034 zilc->zc_nused = lwb->lwb_nused; 1035 zilc->zc_eck.zec_cksum = lwb->lwb_blk.blk_cksum; 1036 1037 /* 1038 * clear unused data for security 1039 */ 1040 bzero(lwb->lwb_buf + lwb->lwb_nused, wsz - lwb->lwb_nused); 1041 1042 zio_nowait(lwb->lwb_zio); /* Kick off the write for the old log block */ 1043 1044 /* 1045 * If there was an allocation failure then nlwb will be null which 1046 * forces a txg_wait_synced(). 1047 */ 1048 return (nlwb); 1049 } 1050 1051 static lwb_t * 1052 zil_lwb_commit(zilog_t *zilog, itx_t *itx, lwb_t *lwb) 1053 { 1054 lr_t *lrc = &itx->itx_lr; /* common log record */ 1055 lr_write_t *lrw = (lr_write_t *)lrc; 1056 char *lr_buf; 1057 uint64_t txg = lrc->lrc_txg; 1058 uint64_t reclen = lrc->lrc_reclen; 1059 uint64_t dlen = 0; 1060 1061 if (lwb == NULL) 1062 return (NULL); 1063 1064 ASSERT(lwb->lwb_buf != NULL); 1065 1066 if (lrc->lrc_txtype == TX_WRITE && itx->itx_wr_state == WR_NEED_COPY) 1067 dlen = P2ROUNDUP_TYPED( 1068 lrw->lr_length, sizeof (uint64_t), uint64_t); 1069 1070 zilog->zl_cur_used += (reclen + dlen); 1071 1072 zil_lwb_write_init(zilog, lwb); 1073 1074 /* 1075 * If this record won't fit in the current log block, start a new one. 1076 */ 1077 if (lwb->lwb_nused + reclen + dlen > lwb->lwb_sz) { 1078 lwb = zil_lwb_write_start(zilog, lwb); 1079 if (lwb == NULL) 1080 return (NULL); 1081 zil_lwb_write_init(zilog, lwb); 1082 ASSERT(LWB_EMPTY(lwb)); 1083 if (lwb->lwb_nused + reclen + dlen > lwb->lwb_sz) { 1084 txg_wait_synced(zilog->zl_dmu_pool, txg); 1085 return (lwb); 1086 } 1087 } 1088 1089 lr_buf = lwb->lwb_buf + lwb->lwb_nused; 1090 bcopy(lrc, lr_buf, reclen); 1091 lrc = (lr_t *)lr_buf; 1092 lrw = (lr_write_t *)lrc; 1093 1094 /* 1095 * If it's a write, fetch the data or get its blkptr as appropriate. 1096 */ 1097 if (lrc->lrc_txtype == TX_WRITE) { 1098 if (txg > spa_freeze_txg(zilog->zl_spa)) 1099 txg_wait_synced(zilog->zl_dmu_pool, txg); 1100 if (itx->itx_wr_state != WR_COPIED) { 1101 char *dbuf; 1102 int error; 1103 1104 if (dlen) { 1105 ASSERT(itx->itx_wr_state == WR_NEED_COPY); 1106 dbuf = lr_buf + reclen; 1107 lrw->lr_common.lrc_reclen += dlen; 1108 } else { 1109 ASSERT(itx->itx_wr_state == WR_INDIRECT); 1110 dbuf = NULL; 1111 } 1112 error = zilog->zl_get_data( 1113 itx->itx_private, lrw, dbuf, lwb->lwb_zio); 1114 if (error == EIO) { 1115 txg_wait_synced(zilog->zl_dmu_pool, txg); 1116 return (lwb); 1117 } 1118 if (error != 0) { 1119 ASSERT(error == ENOENT || error == EEXIST || 1120 error == EALREADY); 1121 return (lwb); 1122 } 1123 } 1124 } 1125 1126 /* 1127 * We're actually making an entry, so update lrc_seq to be the 1128 * log record sequence number. Note that this is generally not 1129 * equal to the itx sequence number because not all transactions 1130 * are synchronous, and sometimes spa_sync() gets there first. 1131 */ 1132 lrc->lrc_seq = ++zilog->zl_lr_seq; /* we are single threaded */ 1133 lwb->lwb_nused += reclen + dlen; 1134 lwb->lwb_max_txg = MAX(lwb->lwb_max_txg, txg); 1135 ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_sz); 1136 ASSERT0(P2PHASE(lwb->lwb_nused, sizeof (uint64_t))); 1137 1138 return (lwb); 1139 } 1140 1141 itx_t * 1142 zil_itx_create(uint64_t txtype, size_t lrsize) 1143 { 1144 itx_t *itx; 1145 1146 lrsize = P2ROUNDUP_TYPED(lrsize, sizeof (uint64_t), size_t); 1147 1148 itx = kmem_alloc(offsetof(itx_t, itx_lr) + lrsize, KM_SLEEP); 1149 itx->itx_lr.lrc_txtype = txtype; 1150 itx->itx_lr.lrc_reclen = lrsize; 1151 itx->itx_sod = lrsize; /* if write & WR_NEED_COPY will be increased */ 1152 itx->itx_lr.lrc_seq = 0; /* defensive */ 1153 itx->itx_sync = B_TRUE; /* default is synchronous */ 1154 1155 return (itx); 1156 } 1157 1158 void 1159 zil_itx_destroy(itx_t *itx) 1160 { 1161 kmem_free(itx, offsetof(itx_t, itx_lr) + itx->itx_lr.lrc_reclen); 1162 } 1163 1164 /* 1165 * Free up the sync and async itxs. The itxs_t has already been detached 1166 * so no locks are needed. 1167 */ 1168 static void 1169 zil_itxg_clean(itxs_t *itxs) 1170 { 1171 itx_t *itx; 1172 list_t *list; 1173 avl_tree_t *t; 1174 void *cookie; 1175 itx_async_node_t *ian; 1176 1177 list = &itxs->i_sync_list; 1178 while ((itx = list_head(list)) != NULL) { 1179 list_remove(list, itx); 1180 kmem_free(itx, offsetof(itx_t, itx_lr) + 1181 itx->itx_lr.lrc_reclen); 1182 } 1183 1184 cookie = NULL; 1185 t = &itxs->i_async_tree; 1186 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1187 list = &ian->ia_list; 1188 while ((itx = list_head(list)) != NULL) { 1189 list_remove(list, itx); 1190 kmem_free(itx, offsetof(itx_t, itx_lr) + 1191 itx->itx_lr.lrc_reclen); 1192 } 1193 list_destroy(list); 1194 kmem_free(ian, sizeof (itx_async_node_t)); 1195 } 1196 avl_destroy(t); 1197 1198 kmem_free(itxs, sizeof (itxs_t)); 1199 } 1200 1201 static int 1202 zil_aitx_compare(const void *x1, const void *x2) 1203 { 1204 const uint64_t o1 = ((itx_async_node_t *)x1)->ia_foid; 1205 const uint64_t o2 = ((itx_async_node_t *)x2)->ia_foid; 1206 1207 if (o1 < o2) 1208 return (-1); 1209 if (o1 > o2) 1210 return (1); 1211 1212 return (0); 1213 } 1214 1215 /* 1216 * Remove all async itx with the given oid. 1217 */ 1218 static void 1219 zil_remove_async(zilog_t *zilog, uint64_t oid) 1220 { 1221 uint64_t otxg, txg; 1222 itx_async_node_t *ian; 1223 avl_tree_t *t; 1224 avl_index_t where; 1225 list_t clean_list; 1226 itx_t *itx; 1227 1228 ASSERT(oid != 0); 1229 list_create(&clean_list, sizeof (itx_t), offsetof(itx_t, itx_node)); 1230 1231 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1232 otxg = ZILTEST_TXG; 1233 else 1234 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1235 1236 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1237 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1238 1239 mutex_enter(&itxg->itxg_lock); 1240 if (itxg->itxg_txg != txg) { 1241 mutex_exit(&itxg->itxg_lock); 1242 continue; 1243 } 1244 1245 /* 1246 * Locate the object node and append its list. 1247 */ 1248 t = &itxg->itxg_itxs->i_async_tree; 1249 ian = avl_find(t, &oid, &where); 1250 if (ian != NULL) 1251 list_move_tail(&clean_list, &ian->ia_list); 1252 mutex_exit(&itxg->itxg_lock); 1253 } 1254 while ((itx = list_head(&clean_list)) != NULL) { 1255 list_remove(&clean_list, itx); 1256 kmem_free(itx, offsetof(itx_t, itx_lr) + 1257 itx->itx_lr.lrc_reclen); 1258 } 1259 list_destroy(&clean_list); 1260 } 1261 1262 void 1263 zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx) 1264 { 1265 uint64_t txg; 1266 itxg_t *itxg; 1267 itxs_t *itxs, *clean = NULL; 1268 1269 /* 1270 * Object ids can be re-instantiated in the next txg so 1271 * remove any async transactions to avoid future leaks. 1272 * This can happen if a fsync occurs on the re-instantiated 1273 * object for a WR_INDIRECT or WR_NEED_COPY write, which gets 1274 * the new file data and flushes a write record for the old object. 1275 */ 1276 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_REMOVE) 1277 zil_remove_async(zilog, itx->itx_oid); 1278 1279 /* 1280 * Ensure the data of a renamed file is committed before the rename. 1281 */ 1282 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_RENAME) 1283 zil_async_to_sync(zilog, itx->itx_oid); 1284 1285 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) 1286 txg = ZILTEST_TXG; 1287 else 1288 txg = dmu_tx_get_txg(tx); 1289 1290 itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1291 mutex_enter(&itxg->itxg_lock); 1292 itxs = itxg->itxg_itxs; 1293 if (itxg->itxg_txg != txg) { 1294 if (itxs != NULL) { 1295 /* 1296 * The zil_clean callback hasn't got around to cleaning 1297 * this itxg. Save the itxs for release below. 1298 * This should be rare. 1299 */ 1300 zfs_dbgmsg("zil_itx_assign: missed itx cleanup for " 1301 "txg %llu", itxg->itxg_txg); 1302 atomic_add_64(&zilog->zl_itx_list_sz, -itxg->itxg_sod); 1303 itxg->itxg_sod = 0; 1304 clean = itxg->itxg_itxs; 1305 } 1306 ASSERT(itxg->itxg_sod == 0); 1307 itxg->itxg_txg = txg; 1308 itxs = itxg->itxg_itxs = kmem_zalloc(sizeof (itxs_t), KM_SLEEP); 1309 1310 list_create(&itxs->i_sync_list, sizeof (itx_t), 1311 offsetof(itx_t, itx_node)); 1312 avl_create(&itxs->i_async_tree, zil_aitx_compare, 1313 sizeof (itx_async_node_t), 1314 offsetof(itx_async_node_t, ia_node)); 1315 } 1316 if (itx->itx_sync) { 1317 list_insert_tail(&itxs->i_sync_list, itx); 1318 atomic_add_64(&zilog->zl_itx_list_sz, itx->itx_sod); 1319 itxg->itxg_sod += itx->itx_sod; 1320 } else { 1321 avl_tree_t *t = &itxs->i_async_tree; 1322 uint64_t foid = ((lr_ooo_t *)&itx->itx_lr)->lr_foid; 1323 itx_async_node_t *ian; 1324 avl_index_t where; 1325 1326 ian = avl_find(t, &foid, &where); 1327 if (ian == NULL) { 1328 ian = kmem_alloc(sizeof (itx_async_node_t), KM_SLEEP); 1329 list_create(&ian->ia_list, sizeof (itx_t), 1330 offsetof(itx_t, itx_node)); 1331 ian->ia_foid = foid; 1332 avl_insert(t, ian, where); 1333 } 1334 list_insert_tail(&ian->ia_list, itx); 1335 } 1336 1337 itx->itx_lr.lrc_txg = dmu_tx_get_txg(tx); 1338 zilog_dirty(zilog, txg); 1339 mutex_exit(&itxg->itxg_lock); 1340 1341 /* Release the old itxs now we've dropped the lock */ 1342 if (clean != NULL) 1343 zil_itxg_clean(clean); 1344 } 1345 1346 /* 1347 * If there are any in-memory intent log transactions which have now been 1348 * synced then start up a taskq to free them. We should only do this after we 1349 * have written out the uberblocks (i.e. txg has been comitted) so that 1350 * don't inadvertently clean out in-memory log records that would be required 1351 * by zil_commit(). 1352 */ 1353 void 1354 zil_clean(zilog_t *zilog, uint64_t synced_txg) 1355 { 1356 itxg_t *itxg = &zilog->zl_itxg[synced_txg & TXG_MASK]; 1357 itxs_t *clean_me; 1358 1359 mutex_enter(&itxg->itxg_lock); 1360 if (itxg->itxg_itxs == NULL || itxg->itxg_txg == ZILTEST_TXG) { 1361 mutex_exit(&itxg->itxg_lock); 1362 return; 1363 } 1364 ASSERT3U(itxg->itxg_txg, <=, synced_txg); 1365 ASSERT(itxg->itxg_txg != 0); 1366 ASSERT(zilog->zl_clean_taskq != NULL); 1367 atomic_add_64(&zilog->zl_itx_list_sz, -itxg->itxg_sod); 1368 itxg->itxg_sod = 0; 1369 clean_me = itxg->itxg_itxs; 1370 itxg->itxg_itxs = NULL; 1371 itxg->itxg_txg = 0; 1372 mutex_exit(&itxg->itxg_lock); 1373 /* 1374 * Preferably start a task queue to free up the old itxs but 1375 * if taskq_dispatch can't allocate resources to do that then 1376 * free it in-line. This should be rare. Note, using TQ_SLEEP 1377 * created a bad performance problem. 1378 */ 1379 if (taskq_dispatch(zilog->zl_clean_taskq, 1380 (void (*)(void *))zil_itxg_clean, clean_me, TQ_NOSLEEP) == NULL) 1381 zil_itxg_clean(clean_me); 1382 } 1383 1384 /* 1385 * Get the list of itxs to commit into zl_itx_commit_list. 1386 */ 1387 static void 1388 zil_get_commit_list(zilog_t *zilog) 1389 { 1390 uint64_t otxg, txg; 1391 list_t *commit_list = &zilog->zl_itx_commit_list; 1392 uint64_t push_sod = 0; 1393 1394 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1395 otxg = ZILTEST_TXG; 1396 else 1397 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1398 1399 /* 1400 * This is inherently racy, since there is nothing to prevent 1401 * the last synced txg from changing. That's okay since we'll 1402 * only commit things in the future. 1403 */ 1404 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1405 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1406 1407 mutex_enter(&itxg->itxg_lock); 1408 if (itxg->itxg_txg != txg) { 1409 mutex_exit(&itxg->itxg_lock); 1410 continue; 1411 } 1412 1413 /* 1414 * If we're adding itx records to the zl_itx_commit_list, 1415 * then the zil better be dirty in this "txg". We can assert 1416 * that here since we're holding the itxg_lock which will 1417 * prevent spa_sync from cleaning it. Once we add the itxs 1418 * to the zl_itx_commit_list we must commit it to disk even 1419 * if it's unnecessary (i.e. the txg was synced). 1420 */ 1421 ASSERT(zilog_is_dirty_in_txg(zilog, txg) || 1422 spa_freeze_txg(zilog->zl_spa) != UINT64_MAX); 1423 list_move_tail(commit_list, &itxg->itxg_itxs->i_sync_list); 1424 push_sod += itxg->itxg_sod; 1425 itxg->itxg_sod = 0; 1426 1427 mutex_exit(&itxg->itxg_lock); 1428 } 1429 atomic_add_64(&zilog->zl_itx_list_sz, -push_sod); 1430 } 1431 1432 /* 1433 * Move the async itxs for a specified object to commit into sync lists. 1434 */ 1435 static void 1436 zil_async_to_sync(zilog_t *zilog, uint64_t foid) 1437 { 1438 uint64_t otxg, txg; 1439 itx_async_node_t *ian; 1440 avl_tree_t *t; 1441 avl_index_t where; 1442 1443 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1444 otxg = ZILTEST_TXG; 1445 else 1446 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1447 1448 /* 1449 * This is inherently racy, since there is nothing to prevent 1450 * the last synced txg from changing. 1451 */ 1452 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1453 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1454 1455 mutex_enter(&itxg->itxg_lock); 1456 if (itxg->itxg_txg != txg) { 1457 mutex_exit(&itxg->itxg_lock); 1458 continue; 1459 } 1460 1461 /* 1462 * If a foid is specified then find that node and append its 1463 * list. Otherwise walk the tree appending all the lists 1464 * to the sync list. We add to the end rather than the 1465 * beginning to ensure the create has happened. 1466 */ 1467 t = &itxg->itxg_itxs->i_async_tree; 1468 if (foid != 0) { 1469 ian = avl_find(t, &foid, &where); 1470 if (ian != NULL) { 1471 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1472 &ian->ia_list); 1473 } 1474 } else { 1475 void *cookie = NULL; 1476 1477 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1478 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1479 &ian->ia_list); 1480 list_destroy(&ian->ia_list); 1481 kmem_free(ian, sizeof (itx_async_node_t)); 1482 } 1483 } 1484 mutex_exit(&itxg->itxg_lock); 1485 } 1486 } 1487 1488 static void 1489 zil_commit_writer(zilog_t *zilog) 1490 { 1491 uint64_t txg; 1492 itx_t *itx; 1493 lwb_t *lwb; 1494 spa_t *spa = zilog->zl_spa; 1495 int error = 0; 1496 1497 ASSERT(zilog->zl_root_zio == NULL); 1498 1499 mutex_exit(&zilog->zl_lock); 1500 1501 zil_get_commit_list(zilog); 1502 1503 /* 1504 * Return if there's nothing to commit before we dirty the fs by 1505 * calling zil_create(). 1506 */ 1507 if (list_head(&zilog->zl_itx_commit_list) == NULL) { 1508 mutex_enter(&zilog->zl_lock); 1509 return; 1510 } 1511 1512 if (zilog->zl_suspend) { 1513 lwb = NULL; 1514 } else { 1515 lwb = list_tail(&zilog->zl_lwb_list); 1516 if (lwb == NULL) 1517 lwb = zil_create(zilog); 1518 } 1519 1520 DTRACE_PROBE1(zil__cw1, zilog_t *, zilog); 1521 while (itx = list_head(&zilog->zl_itx_commit_list)) { 1522 txg = itx->itx_lr.lrc_txg; 1523 ASSERT3U(txg, !=, 0); 1524 1525 /* 1526 * This is inherently racy and may result in us writing 1527 * out a log block for a txg that was just synced. This is 1528 * ok since we'll end cleaning up that log block the next 1529 * time we call zil_sync(). 1530 */ 1531 if (txg > spa_last_synced_txg(spa) || txg > spa_freeze_txg(spa)) 1532 lwb = zil_lwb_commit(zilog, itx, lwb); 1533 list_remove(&zilog->zl_itx_commit_list, itx); 1534 kmem_free(itx, offsetof(itx_t, itx_lr) 1535 + itx->itx_lr.lrc_reclen); 1536 } 1537 DTRACE_PROBE1(zil__cw2, zilog_t *, zilog); 1538 1539 /* write the last block out */ 1540 if (lwb != NULL && lwb->lwb_zio != NULL) 1541 lwb = zil_lwb_write_start(zilog, lwb); 1542 1543 zilog->zl_cur_used = 0; 1544 1545 /* 1546 * Wait if necessary for the log blocks to be on stable storage. 1547 */ 1548 if (zilog->zl_root_zio) { 1549 error = zio_wait(zilog->zl_root_zio); 1550 zilog->zl_root_zio = NULL; 1551 zil_flush_vdevs(zilog); 1552 } 1553 1554 if (error || lwb == NULL) 1555 txg_wait_synced(zilog->zl_dmu_pool, 0); 1556 1557 mutex_enter(&zilog->zl_lock); 1558 1559 /* 1560 * Remember the highest committed log sequence number for ztest. 1561 * We only update this value when all the log writes succeeded, 1562 * because ztest wants to ASSERT that it got the whole log chain. 1563 */ 1564 if (error == 0 && lwb != NULL) 1565 zilog->zl_commit_lr_seq = zilog->zl_lr_seq; 1566 } 1567 1568 /* 1569 * Commit zfs transactions to stable storage. 1570 * If foid is 0 push out all transactions, otherwise push only those 1571 * for that object or might reference that object. 1572 * 1573 * itxs are committed in batches. In a heavily stressed zil there will be 1574 * a commit writer thread who is writing out a bunch of itxs to the log 1575 * for a set of committing threads (cthreads) in the same batch as the writer. 1576 * Those cthreads are all waiting on the same cv for that batch. 1577 * 1578 * There will also be a different and growing batch of threads that are 1579 * waiting to commit (qthreads). When the committing batch completes 1580 * a transition occurs such that the cthreads exit and the qthreads become 1581 * cthreads. One of the new cthreads becomes the writer thread for the 1582 * batch. Any new threads arriving become new qthreads. 1583 * 1584 * Only 2 condition variables are needed and there's no transition 1585 * between the two cvs needed. They just flip-flop between qthreads 1586 * and cthreads. 1587 * 1588 * Using this scheme we can efficiently wakeup up only those threads 1589 * that have been committed. 1590 */ 1591 void 1592 zil_commit(zilog_t *zilog, uint64_t foid) 1593 { 1594 uint64_t mybatch; 1595 1596 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 1597 return; 1598 1599 /* move the async itxs for the foid to the sync queues */ 1600 zil_async_to_sync(zilog, foid); 1601 1602 mutex_enter(&zilog->zl_lock); 1603 mybatch = zilog->zl_next_batch; 1604 while (zilog->zl_writer) { 1605 cv_wait(&zilog->zl_cv_batch[mybatch & 1], &zilog->zl_lock); 1606 if (mybatch <= zilog->zl_com_batch) { 1607 mutex_exit(&zilog->zl_lock); 1608 return; 1609 } 1610 } 1611 1612 zilog->zl_next_batch++; 1613 zilog->zl_writer = B_TRUE; 1614 zil_commit_writer(zilog); 1615 zilog->zl_com_batch = mybatch; 1616 zilog->zl_writer = B_FALSE; 1617 mutex_exit(&zilog->zl_lock); 1618 1619 /* wake up one thread to become the next writer */ 1620 cv_signal(&zilog->zl_cv_batch[(mybatch+1) & 1]); 1621 1622 /* wake up all threads waiting for this batch to be committed */ 1623 cv_broadcast(&zilog->zl_cv_batch[mybatch & 1]); 1624 } 1625 1626 /* 1627 * Called in syncing context to free committed log blocks and update log header. 1628 */ 1629 void 1630 zil_sync(zilog_t *zilog, dmu_tx_t *tx) 1631 { 1632 zil_header_t *zh = zil_header_in_syncing_context(zilog); 1633 uint64_t txg = dmu_tx_get_txg(tx); 1634 spa_t *spa = zilog->zl_spa; 1635 uint64_t *replayed_seq = &zilog->zl_replayed_seq[txg & TXG_MASK]; 1636 lwb_t *lwb; 1637 1638 /* 1639 * We don't zero out zl_destroy_txg, so make sure we don't try 1640 * to destroy it twice. 1641 */ 1642 if (spa_sync_pass(spa) != 1) 1643 return; 1644 1645 mutex_enter(&zilog->zl_lock); 1646 1647 ASSERT(zilog->zl_stop_sync == 0); 1648 1649 if (*replayed_seq != 0) { 1650 ASSERT(zh->zh_replay_seq < *replayed_seq); 1651 zh->zh_replay_seq = *replayed_seq; 1652 *replayed_seq = 0; 1653 } 1654 1655 if (zilog->zl_destroy_txg == txg) { 1656 blkptr_t blk = zh->zh_log; 1657 1658 ASSERT(list_head(&zilog->zl_lwb_list) == NULL); 1659 1660 bzero(zh, sizeof (zil_header_t)); 1661 bzero(zilog->zl_replayed_seq, sizeof (zilog->zl_replayed_seq)); 1662 1663 if (zilog->zl_keep_first) { 1664 /* 1665 * If this block was part of log chain that couldn't 1666 * be claimed because a device was missing during 1667 * zil_claim(), but that device later returns, 1668 * then this block could erroneously appear valid. 1669 * To guard against this, assign a new GUID to the new 1670 * log chain so it doesn't matter what blk points to. 1671 */ 1672 zil_init_log_chain(zilog, &blk); 1673 zh->zh_log = blk; 1674 } 1675 } 1676 1677 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 1678 zh->zh_log = lwb->lwb_blk; 1679 if (lwb->lwb_buf != NULL || lwb->lwb_max_txg > txg) 1680 break; 1681 list_remove(&zilog->zl_lwb_list, lwb); 1682 zio_free_zil(spa, txg, &lwb->lwb_blk); 1683 kmem_cache_free(zil_lwb_cache, lwb); 1684 1685 /* 1686 * If we don't have anything left in the lwb list then 1687 * we've had an allocation failure and we need to zero 1688 * out the zil_header blkptr so that we don't end 1689 * up freeing the same block twice. 1690 */ 1691 if (list_head(&zilog->zl_lwb_list) == NULL) 1692 BP_ZERO(&zh->zh_log); 1693 } 1694 mutex_exit(&zilog->zl_lock); 1695 } 1696 1697 void 1698 zil_init(void) 1699 { 1700 zil_lwb_cache = kmem_cache_create("zil_lwb_cache", 1701 sizeof (struct lwb), 0, NULL, NULL, NULL, NULL, NULL, 0); 1702 } 1703 1704 void 1705 zil_fini(void) 1706 { 1707 kmem_cache_destroy(zil_lwb_cache); 1708 } 1709 1710 void 1711 zil_set_sync(zilog_t *zilog, uint64_t sync) 1712 { 1713 zilog->zl_sync = sync; 1714 } 1715 1716 void 1717 zil_set_logbias(zilog_t *zilog, uint64_t logbias) 1718 { 1719 zilog->zl_logbias = logbias; 1720 } 1721 1722 zilog_t * 1723 zil_alloc(objset_t *os, zil_header_t *zh_phys) 1724 { 1725 zilog_t *zilog; 1726 1727 zilog = kmem_zalloc(sizeof (zilog_t), KM_SLEEP); 1728 1729 zilog->zl_header = zh_phys; 1730 zilog->zl_os = os; 1731 zilog->zl_spa = dmu_objset_spa(os); 1732 zilog->zl_dmu_pool = dmu_objset_pool(os); 1733 zilog->zl_destroy_txg = TXG_INITIAL - 1; 1734 zilog->zl_logbias = dmu_objset_logbias(os); 1735 zilog->zl_sync = dmu_objset_syncprop(os); 1736 zilog->zl_next_batch = 1; 1737 1738 mutex_init(&zilog->zl_lock, NULL, MUTEX_DEFAULT, NULL); 1739 1740 for (int i = 0; i < TXG_SIZE; i++) { 1741 mutex_init(&zilog->zl_itxg[i].itxg_lock, NULL, 1742 MUTEX_DEFAULT, NULL); 1743 } 1744 1745 list_create(&zilog->zl_lwb_list, sizeof (lwb_t), 1746 offsetof(lwb_t, lwb_node)); 1747 1748 list_create(&zilog->zl_itx_commit_list, sizeof (itx_t), 1749 offsetof(itx_t, itx_node)); 1750 1751 mutex_init(&zilog->zl_vdev_lock, NULL, MUTEX_DEFAULT, NULL); 1752 1753 avl_create(&zilog->zl_vdev_tree, zil_vdev_compare, 1754 sizeof (zil_vdev_node_t), offsetof(zil_vdev_node_t, zv_node)); 1755 1756 cv_init(&zilog->zl_cv_writer, NULL, CV_DEFAULT, NULL); 1757 cv_init(&zilog->zl_cv_suspend, NULL, CV_DEFAULT, NULL); 1758 cv_init(&zilog->zl_cv_batch[0], NULL, CV_DEFAULT, NULL); 1759 cv_init(&zilog->zl_cv_batch[1], NULL, CV_DEFAULT, NULL); 1760 1761 return (zilog); 1762 } 1763 1764 void 1765 zil_free(zilog_t *zilog) 1766 { 1767 zilog->zl_stop_sync = 1; 1768 1769 ASSERT0(zilog->zl_suspend); 1770 ASSERT0(zilog->zl_suspending); 1771 1772 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1773 list_destroy(&zilog->zl_lwb_list); 1774 1775 avl_destroy(&zilog->zl_vdev_tree); 1776 mutex_destroy(&zilog->zl_vdev_lock); 1777 1778 ASSERT(list_is_empty(&zilog->zl_itx_commit_list)); 1779 list_destroy(&zilog->zl_itx_commit_list); 1780 1781 for (int i = 0; i < TXG_SIZE; i++) { 1782 /* 1783 * It's possible for an itx to be generated that doesn't dirty 1784 * a txg (e.g. ztest TX_TRUNCATE). So there's no zil_clean() 1785 * callback to remove the entry. We remove those here. 1786 * 1787 * Also free up the ziltest itxs. 1788 */ 1789 if (zilog->zl_itxg[i].itxg_itxs) 1790 zil_itxg_clean(zilog->zl_itxg[i].itxg_itxs); 1791 mutex_destroy(&zilog->zl_itxg[i].itxg_lock); 1792 } 1793 1794 mutex_destroy(&zilog->zl_lock); 1795 1796 cv_destroy(&zilog->zl_cv_writer); 1797 cv_destroy(&zilog->zl_cv_suspend); 1798 cv_destroy(&zilog->zl_cv_batch[0]); 1799 cv_destroy(&zilog->zl_cv_batch[1]); 1800 1801 kmem_free(zilog, sizeof (zilog_t)); 1802 } 1803 1804 /* 1805 * Open an intent log. 1806 */ 1807 zilog_t * 1808 zil_open(objset_t *os, zil_get_data_t *get_data) 1809 { 1810 zilog_t *zilog = dmu_objset_zil(os); 1811 1812 ASSERT(zilog->zl_clean_taskq == NULL); 1813 ASSERT(zilog->zl_get_data == NULL); 1814 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1815 1816 zilog->zl_get_data = get_data; 1817 zilog->zl_clean_taskq = taskq_create("zil_clean", 1, minclsyspri, 1818 2, 2, TASKQ_PREPOPULATE); 1819 1820 return (zilog); 1821 } 1822 1823 /* 1824 * Close an intent log. 1825 */ 1826 void 1827 zil_close(zilog_t *zilog) 1828 { 1829 lwb_t *lwb; 1830 uint64_t txg = 0; 1831 1832 zil_commit(zilog, 0); /* commit all itx */ 1833 1834 /* 1835 * The lwb_max_txg for the stubby lwb will reflect the last activity 1836 * for the zil. After a txg_wait_synced() on the txg we know all the 1837 * callbacks have occurred that may clean the zil. Only then can we 1838 * destroy the zl_clean_taskq. 1839 */ 1840 mutex_enter(&zilog->zl_lock); 1841 lwb = list_tail(&zilog->zl_lwb_list); 1842 if (lwb != NULL) 1843 txg = lwb->lwb_max_txg; 1844 mutex_exit(&zilog->zl_lock); 1845 if (txg) 1846 txg_wait_synced(zilog->zl_dmu_pool, txg); 1847 1848 if (zilog_is_dirty(zilog)) 1849 zfs_dbgmsg("zil (%p) is dirty, txg %llu", zilog, txg); 1850 VERIFY(!zilog_is_dirty(zilog)); 1851 1852 taskq_destroy(zilog->zl_clean_taskq); 1853 zilog->zl_clean_taskq = NULL; 1854 zilog->zl_get_data = NULL; 1855 1856 /* 1857 * We should have only one LWB left on the list; remove it now. 1858 */ 1859 mutex_enter(&zilog->zl_lock); 1860 lwb = list_head(&zilog->zl_lwb_list); 1861 if (lwb != NULL) { 1862 ASSERT(lwb == list_tail(&zilog->zl_lwb_list)); 1863 list_remove(&zilog->zl_lwb_list, lwb); 1864 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 1865 kmem_cache_free(zil_lwb_cache, lwb); 1866 } 1867 mutex_exit(&zilog->zl_lock); 1868 } 1869 1870 static char *suspend_tag = "zil suspending"; 1871 1872 /* 1873 * Suspend an intent log. While in suspended mode, we still honor 1874 * synchronous semantics, but we rely on txg_wait_synced() to do it. 1875 * On old version pools, we suspend the log briefly when taking a 1876 * snapshot so that it will have an empty intent log. 1877 * 1878 * Long holds are not really intended to be used the way we do here -- 1879 * held for such a short time. A concurrent caller of dsl_dataset_long_held() 1880 * could fail. Therefore we take pains to only put a long hold if it is 1881 * actually necessary. Fortunately, it will only be necessary if the 1882 * objset is currently mounted (or the ZVOL equivalent). In that case it 1883 * will already have a long hold, so we are not really making things any worse. 1884 * 1885 * Ideally, we would locate the existing long-holder (i.e. the zfsvfs_t or 1886 * zvol_state_t), and use their mechanism to prevent their hold from being 1887 * dropped (e.g. VFS_HOLD()). However, that would be even more pain for 1888 * very little gain. 1889 * 1890 * if cookiep == NULL, this does both the suspend & resume. 1891 * Otherwise, it returns with the dataset "long held", and the cookie 1892 * should be passed into zil_resume(). 1893 */ 1894 int 1895 zil_suspend(const char *osname, void **cookiep) 1896 { 1897 objset_t *os; 1898 zilog_t *zilog; 1899 const zil_header_t *zh; 1900 int error; 1901 1902 error = dmu_objset_hold(osname, suspend_tag, &os); 1903 if (error != 0) 1904 return (error); 1905 zilog = dmu_objset_zil(os); 1906 1907 mutex_enter(&zilog->zl_lock); 1908 zh = zilog->zl_header; 1909 1910 if (zh->zh_flags & ZIL_REPLAY_NEEDED) { /* unplayed log */ 1911 mutex_exit(&zilog->zl_lock); 1912 dmu_objset_rele(os, suspend_tag); 1913 return (SET_ERROR(EBUSY)); 1914 } 1915 1916 /* 1917 * Don't put a long hold in the cases where we can avoid it. This 1918 * is when there is no cookie so we are doing a suspend & resume 1919 * (i.e. called from zil_vdev_offline()), and there's nothing to do 1920 * for the suspend because it's already suspended, or there's no ZIL. 1921 */ 1922 if (cookiep == NULL && !zilog->zl_suspending && 1923 (zilog->zl_suspend > 0 || BP_IS_HOLE(&zh->zh_log))) { 1924 mutex_exit(&zilog->zl_lock); 1925 dmu_objset_rele(os, suspend_tag); 1926 return (0); 1927 } 1928 1929 dsl_dataset_long_hold(dmu_objset_ds(os), suspend_tag); 1930 dsl_pool_rele(dmu_objset_pool(os), suspend_tag); 1931 1932 zilog->zl_suspend++; 1933 1934 if (zilog->zl_suspend > 1) { 1935 /* 1936 * Someone else is already suspending it. 1937 * Just wait for them to finish. 1938 */ 1939 1940 while (zilog->zl_suspending) 1941 cv_wait(&zilog->zl_cv_suspend, &zilog->zl_lock); 1942 mutex_exit(&zilog->zl_lock); 1943 1944 if (cookiep == NULL) 1945 zil_resume(os); 1946 else 1947 *cookiep = os; 1948 return (0); 1949 } 1950 1951 /* 1952 * If there is no pointer to an on-disk block, this ZIL must not 1953 * be active (e.g. filesystem not mounted), so there's nothing 1954 * to clean up. 1955 */ 1956 if (BP_IS_HOLE(&zh->zh_log)) { 1957 ASSERT(cookiep != NULL); /* fast path already handled */ 1958 1959 *cookiep = os; 1960 mutex_exit(&zilog->zl_lock); 1961 return (0); 1962 } 1963 1964 zilog->zl_suspending = B_TRUE; 1965 mutex_exit(&zilog->zl_lock); 1966 1967 zil_commit(zilog, 0); 1968 1969 zil_destroy(zilog, B_FALSE); 1970 1971 mutex_enter(&zilog->zl_lock); 1972 zilog->zl_suspending = B_FALSE; 1973 cv_broadcast(&zilog->zl_cv_suspend); 1974 mutex_exit(&zilog->zl_lock); 1975 1976 if (cookiep == NULL) 1977 zil_resume(os); 1978 else 1979 *cookiep = os; 1980 return (0); 1981 } 1982 1983 void 1984 zil_resume(void *cookie) 1985 { 1986 objset_t *os = cookie; 1987 zilog_t *zilog = dmu_objset_zil(os); 1988 1989 mutex_enter(&zilog->zl_lock); 1990 ASSERT(zilog->zl_suspend != 0); 1991 zilog->zl_suspend--; 1992 mutex_exit(&zilog->zl_lock); 1993 dsl_dataset_long_rele(dmu_objset_ds(os), suspend_tag); 1994 dsl_dataset_rele(dmu_objset_ds(os), suspend_tag); 1995 } 1996 1997 typedef struct zil_replay_arg { 1998 zil_replay_func_t **zr_replay; 1999 void *zr_arg; 2000 boolean_t zr_byteswap; 2001 char *zr_lr; 2002 } zil_replay_arg_t; 2003 2004 static int 2005 zil_replay_error(zilog_t *zilog, lr_t *lr, int error) 2006 { 2007 char name[ZFS_MAX_DATASET_NAME_LEN]; 2008 2009 zilog->zl_replaying_seq--; /* didn't actually replay this one */ 2010 2011 dmu_objset_name(zilog->zl_os, name); 2012 2013 cmn_err(CE_WARN, "ZFS replay transaction error %d, " 2014 "dataset %s, seq 0x%llx, txtype %llu %s\n", error, name, 2015 (u_longlong_t)lr->lrc_seq, 2016 (u_longlong_t)(lr->lrc_txtype & ~TX_CI), 2017 (lr->lrc_txtype & TX_CI) ? "CI" : ""); 2018 2019 return (error); 2020 } 2021 2022 static int 2023 zil_replay_log_record(zilog_t *zilog, lr_t *lr, void *zra, uint64_t claim_txg) 2024 { 2025 zil_replay_arg_t *zr = zra; 2026 const zil_header_t *zh = zilog->zl_header; 2027 uint64_t reclen = lr->lrc_reclen; 2028 uint64_t txtype = lr->lrc_txtype; 2029 int error = 0; 2030 2031 zilog->zl_replaying_seq = lr->lrc_seq; 2032 2033 if (lr->lrc_seq <= zh->zh_replay_seq) /* already replayed */ 2034 return (0); 2035 2036 if (lr->lrc_txg < claim_txg) /* already committed */ 2037 return (0); 2038 2039 /* Strip case-insensitive bit, still present in log record */ 2040 txtype &= ~TX_CI; 2041 2042 if (txtype == 0 || txtype >= TX_MAX_TYPE) 2043 return (zil_replay_error(zilog, lr, EINVAL)); 2044 2045 /* 2046 * If this record type can be logged out of order, the object 2047 * (lr_foid) may no longer exist. That's legitimate, not an error. 2048 */ 2049 if (TX_OOO(txtype)) { 2050 error = dmu_object_info(zilog->zl_os, 2051 ((lr_ooo_t *)lr)->lr_foid, NULL); 2052 if (error == ENOENT || error == EEXIST) 2053 return (0); 2054 } 2055 2056 /* 2057 * Make a copy of the data so we can revise and extend it. 2058 */ 2059 bcopy(lr, zr->zr_lr, reclen); 2060 2061 /* 2062 * If this is a TX_WRITE with a blkptr, suck in the data. 2063 */ 2064 if (txtype == TX_WRITE && reclen == sizeof (lr_write_t)) { 2065 error = zil_read_log_data(zilog, (lr_write_t *)lr, 2066 zr->zr_lr + reclen); 2067 if (error != 0) 2068 return (zil_replay_error(zilog, lr, error)); 2069 } 2070 2071 /* 2072 * The log block containing this lr may have been byteswapped 2073 * so that we can easily examine common fields like lrc_txtype. 2074 * However, the log is a mix of different record types, and only the 2075 * replay vectors know how to byteswap their records. Therefore, if 2076 * the lr was byteswapped, undo it before invoking the replay vector. 2077 */ 2078 if (zr->zr_byteswap) 2079 byteswap_uint64_array(zr->zr_lr, reclen); 2080 2081 /* 2082 * We must now do two things atomically: replay this log record, 2083 * and update the log header sequence number to reflect the fact that 2084 * we did so. At the end of each replay function the sequence number 2085 * is updated if we are in replay mode. 2086 */ 2087 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, zr->zr_byteswap); 2088 if (error != 0) { 2089 /* 2090 * The DMU's dnode layer doesn't see removes until the txg 2091 * commits, so a subsequent claim can spuriously fail with 2092 * EEXIST. So if we receive any error we try syncing out 2093 * any removes then retry the transaction. Note that we 2094 * specify B_FALSE for byteswap now, so we don't do it twice. 2095 */ 2096 txg_wait_synced(spa_get_dsl(zilog->zl_spa), 0); 2097 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, B_FALSE); 2098 if (error != 0) 2099 return (zil_replay_error(zilog, lr, error)); 2100 } 2101 return (0); 2102 } 2103 2104 /* ARGSUSED */ 2105 static int 2106 zil_incr_blks(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 2107 { 2108 zilog->zl_replay_blks++; 2109 2110 return (0); 2111 } 2112 2113 /* 2114 * If this dataset has a non-empty intent log, replay it and destroy it. 2115 */ 2116 void 2117 zil_replay(objset_t *os, void *arg, zil_replay_func_t *replay_func[TX_MAX_TYPE]) 2118 { 2119 zilog_t *zilog = dmu_objset_zil(os); 2120 const zil_header_t *zh = zilog->zl_header; 2121 zil_replay_arg_t zr; 2122 2123 if ((zh->zh_flags & ZIL_REPLAY_NEEDED) == 0) { 2124 zil_destroy(zilog, B_TRUE); 2125 return; 2126 } 2127 2128 zr.zr_replay = replay_func; 2129 zr.zr_arg = arg; 2130 zr.zr_byteswap = BP_SHOULD_BYTESWAP(&zh->zh_log); 2131 zr.zr_lr = kmem_alloc(2 * SPA_MAXBLOCKSIZE, KM_SLEEP); 2132 2133 /* 2134 * Wait for in-progress removes to sync before starting replay. 2135 */ 2136 txg_wait_synced(zilog->zl_dmu_pool, 0); 2137 2138 zilog->zl_replay = B_TRUE; 2139 zilog->zl_replay_time = ddi_get_lbolt(); 2140 ASSERT(zilog->zl_replay_blks == 0); 2141 (void) zil_parse(zilog, zil_incr_blks, zil_replay_log_record, &zr, 2142 zh->zh_claim_txg); 2143 kmem_free(zr.zr_lr, 2 * SPA_MAXBLOCKSIZE); 2144 2145 zil_destroy(zilog, B_FALSE); 2146 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 2147 zilog->zl_replay = B_FALSE; 2148 } 2149 2150 boolean_t 2151 zil_replaying(zilog_t *zilog, dmu_tx_t *tx) 2152 { 2153 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 2154 return (B_TRUE); 2155 2156 if (zilog->zl_replay) { 2157 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 2158 zilog->zl_replayed_seq[dmu_tx_get_txg(tx) & TXG_MASK] = 2159 zilog->zl_replaying_seq; 2160 return (B_TRUE); 2161 } 2162 2163 return (B_FALSE); 2164 } 2165 2166 /* ARGSUSED */ 2167 int 2168 zil_vdev_offline(const char *osname, void *arg) 2169 { 2170 int error; 2171 2172 error = zil_suspend(osname, NULL); 2173 if (error != 0) 2174 return (SET_ERROR(EEXIST)); 2175 return (0); 2176 } 2177