zil.c revision 307108
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, 2014 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 43/* 44 * The zfs intent log (ZIL) saves transaction records of system calls 45 * that change the file system in memory with enough information 46 * to be able to replay them. These are stored in memory until 47 * either the DMU transaction group (txg) commits them to the stable pool 48 * and they can be discarded, or they are flushed to the stable log 49 * (also in the pool) due to a fsync, O_DSYNC or other synchronous 50 * requirement. In the event of a panic or power fail then those log 51 * records (transactions) are replayed. 52 * 53 * There is one ZIL per file system. Its on-disk (pool) format consists 54 * of 3 parts: 55 * 56 * - ZIL header 57 * - ZIL blocks 58 * - ZIL records 59 * 60 * A log record holds a system call transaction. Log blocks can 61 * hold many log records and the blocks are chained together. 62 * Each ZIL block contains a block pointer (blkptr_t) to the next 63 * ZIL block in the chain. The ZIL header points to the first 64 * block in the chain. Note there is not a fixed place in the pool 65 * to hold blocks. They are dynamically allocated and freed as 66 * needed from the blocks available. Figure X shows the ZIL structure: 67 */ 68 69/* 70 * Disable intent logging replay. This global ZIL switch affects all pools. 71 */ 72int zil_replay_disable = 0; 73SYSCTL_DECL(_vfs_zfs); 74SYSCTL_INT(_vfs_zfs, OID_AUTO, zil_replay_disable, CTLFLAG_RWTUN, 75 &zil_replay_disable, 0, "Disable intent logging replay"); 76 77/* 78 * Tunable parameter for debugging or performance analysis. Setting 79 * zfs_nocacheflush will cause corruption on power loss if a volatile 80 * out-of-order write cache is enabled. 81 */ 82boolean_t zfs_nocacheflush = B_FALSE; 83SYSCTL_INT(_vfs_zfs, OID_AUTO, cache_flush_disable, CTLFLAG_RDTUN, 84 &zfs_nocacheflush, 0, "Disable cache flush"); 85boolean_t zfs_trim_enabled = B_TRUE; 86SYSCTL_DECL(_vfs_zfs_trim); 87SYSCTL_INT(_vfs_zfs_trim, OID_AUTO, enabled, CTLFLAG_RDTUN, &zfs_trim_enabled, 0, 88 "Enable ZFS TRIM"); 89 90static kmem_cache_t *zil_lwb_cache; 91 92static void zil_async_to_sync(zilog_t *zilog, uint64_t foid); 93 94#define LWB_EMPTY(lwb) ((BP_GET_LSIZE(&lwb->lwb_blk) - \ 95 sizeof (zil_chain_t)) == (lwb->lwb_sz - lwb->lwb_nused)) 96 97 98/* 99 * ziltest is by and large an ugly hack, but very useful in 100 * checking replay without tedious work. 101 * When running ziltest we want to keep all itx's and so maintain 102 * a single list in the zl_itxg[] that uses a high txg: ZILTEST_TXG 103 * We subtract TXG_CONCURRENT_STATES to allow for common code. 104 */ 105#define ZILTEST_TXG (UINT64_MAX - TXG_CONCURRENT_STATES) 106 107static int 108zil_bp_compare(const void *x1, const void *x2) 109{ 110 const dva_t *dva1 = &((zil_bp_node_t *)x1)->zn_dva; 111 const dva_t *dva2 = &((zil_bp_node_t *)x2)->zn_dva; 112 113 if (DVA_GET_VDEV(dva1) < DVA_GET_VDEV(dva2)) 114 return (-1); 115 if (DVA_GET_VDEV(dva1) > DVA_GET_VDEV(dva2)) 116 return (1); 117 118 if (DVA_GET_OFFSET(dva1) < DVA_GET_OFFSET(dva2)) 119 return (-1); 120 if (DVA_GET_OFFSET(dva1) > DVA_GET_OFFSET(dva2)) 121 return (1); 122 123 return (0); 124} 125 126static void 127zil_bp_tree_init(zilog_t *zilog) 128{ 129 avl_create(&zilog->zl_bp_tree, zil_bp_compare, 130 sizeof (zil_bp_node_t), offsetof(zil_bp_node_t, zn_node)); 131} 132 133static void 134zil_bp_tree_fini(zilog_t *zilog) 135{ 136 avl_tree_t *t = &zilog->zl_bp_tree; 137 zil_bp_node_t *zn; 138 void *cookie = NULL; 139 140 while ((zn = avl_destroy_nodes(t, &cookie)) != NULL) 141 kmem_free(zn, sizeof (zil_bp_node_t)); 142 143 avl_destroy(t); 144} 145 146int 147zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp) 148{ 149 avl_tree_t *t = &zilog->zl_bp_tree; 150 const dva_t *dva; 151 zil_bp_node_t *zn; 152 avl_index_t where; 153 154 if (BP_IS_EMBEDDED(bp)) 155 return (0); 156 157 dva = BP_IDENTITY(bp); 158 159 if (avl_find(t, dva, &where) != NULL) 160 return (SET_ERROR(EEXIST)); 161 162 zn = kmem_alloc(sizeof (zil_bp_node_t), KM_SLEEP); 163 zn->zn_dva = *dva; 164 avl_insert(t, zn, where); 165 166 return (0); 167} 168 169static zil_header_t * 170zil_header_in_syncing_context(zilog_t *zilog) 171{ 172 return ((zil_header_t *)zilog->zl_header); 173} 174 175static void 176zil_init_log_chain(zilog_t *zilog, blkptr_t *bp) 177{ 178 zio_cksum_t *zc = &bp->blk_cksum; 179 180 zc->zc_word[ZIL_ZC_GUID_0] = spa_get_random(-1ULL); 181 zc->zc_word[ZIL_ZC_GUID_1] = spa_get_random(-1ULL); 182 zc->zc_word[ZIL_ZC_OBJSET] = dmu_objset_id(zilog->zl_os); 183 zc->zc_word[ZIL_ZC_SEQ] = 1ULL; 184} 185 186/* 187 * Read a log block and make sure it's valid. 188 */ 189static int 190zil_read_log_block(zilog_t *zilog, const blkptr_t *bp, blkptr_t *nbp, void *dst, 191 char **end) 192{ 193 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 194 arc_flags_t aflags = ARC_FLAG_WAIT; 195 arc_buf_t *abuf = NULL; 196 zbookmark_phys_t zb; 197 int error; 198 199 if (zilog->zl_header->zh_claim_txg == 0) 200 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 201 202 if (!(zilog->zl_header->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 203 zio_flags |= ZIO_FLAG_SPECULATIVE; 204 205 SET_BOOKMARK(&zb, bp->blk_cksum.zc_word[ZIL_ZC_OBJSET], 206 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); 207 208 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 209 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 210 211 if (error == 0) { 212 zio_cksum_t cksum = bp->blk_cksum; 213 214 /* 215 * Validate the checksummed log block. 216 * 217 * Sequence numbers should be... sequential. The checksum 218 * verifier for the next block should be bp's checksum plus 1. 219 * 220 * Also check the log chain linkage and size used. 221 */ 222 cksum.zc_word[ZIL_ZC_SEQ]++; 223 224 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 225 zil_chain_t *zilc = abuf->b_data; 226 char *lr = (char *)(zilc + 1); 227 uint64_t len = zilc->zc_nused - sizeof (zil_chain_t); 228 229 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 230 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk)) { 231 error = SET_ERROR(ECKSUM); 232 } else { 233 ASSERT3U(len, <=, SPA_OLD_MAXBLOCKSIZE); 234 bcopy(lr, dst, len); 235 *end = (char *)dst + len; 236 *nbp = zilc->zc_next_blk; 237 } 238 } else { 239 char *lr = abuf->b_data; 240 uint64_t size = BP_GET_LSIZE(bp); 241 zil_chain_t *zilc = (zil_chain_t *)(lr + size) - 1; 242 243 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 244 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk) || 245 (zilc->zc_nused > (size - sizeof (*zilc)))) { 246 error = SET_ERROR(ECKSUM); 247 } else { 248 ASSERT3U(zilc->zc_nused, <=, 249 SPA_OLD_MAXBLOCKSIZE); 250 bcopy(lr, dst, zilc->zc_nused); 251 *end = (char *)dst + zilc->zc_nused; 252 *nbp = zilc->zc_next_blk; 253 } 254 } 255 256 VERIFY(arc_buf_remove_ref(abuf, &abuf)); 257 } 258 259 return (error); 260} 261 262/* 263 * Read a TX_WRITE log data block. 264 */ 265static int 266zil_read_log_data(zilog_t *zilog, const lr_write_t *lr, void *wbuf) 267{ 268 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 269 const blkptr_t *bp = &lr->lr_blkptr; 270 arc_flags_t aflags = ARC_FLAG_WAIT; 271 arc_buf_t *abuf = NULL; 272 zbookmark_phys_t zb; 273 int error; 274 275 if (BP_IS_HOLE(bp)) { 276 if (wbuf != NULL) 277 bzero(wbuf, MAX(BP_GET_LSIZE(bp), lr->lr_length)); 278 return (0); 279 } 280 281 if (zilog->zl_header->zh_claim_txg == 0) 282 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 283 284 SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os), lr->lr_foid, 285 ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp)); 286 287 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 288 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 289 290 if (error == 0) { 291 if (wbuf != NULL) 292 bcopy(abuf->b_data, wbuf, arc_buf_size(abuf)); 293 (void) arc_buf_remove_ref(abuf, &abuf); 294 } 295 296 return (error); 297} 298 299/* 300 * Parse the intent log, and call parse_func for each valid record within. 301 */ 302int 303zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func, 304 zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg) 305{ 306 const zil_header_t *zh = zilog->zl_header; 307 boolean_t claimed = !!zh->zh_claim_txg; 308 uint64_t claim_blk_seq = claimed ? zh->zh_claim_blk_seq : UINT64_MAX; 309 uint64_t claim_lr_seq = claimed ? zh->zh_claim_lr_seq : UINT64_MAX; 310 uint64_t max_blk_seq = 0; 311 uint64_t max_lr_seq = 0; 312 uint64_t blk_count = 0; 313 uint64_t lr_count = 0; 314 blkptr_t blk, next_blk; 315 char *lrbuf, *lrp; 316 int error = 0; 317 318 /* 319 * Old logs didn't record the maximum zh_claim_lr_seq. 320 */ 321 if (!(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 322 claim_lr_seq = UINT64_MAX; 323 324 /* 325 * Starting at the block pointed to by zh_log we read the log chain. 326 * For each block in the chain we strongly check that block to 327 * ensure its validity. We stop when an invalid block is found. 328 * For each block pointer in the chain we call parse_blk_func(). 329 * For each record in each valid block we call parse_lr_func(). 330 * If the log has been claimed, stop if we encounter a sequence 331 * number greater than the highest claimed sequence number. 332 */ 333 lrbuf = zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE); 334 zil_bp_tree_init(zilog); 335 336 for (blk = zh->zh_log; !BP_IS_HOLE(&blk); blk = next_blk) { 337 uint64_t blk_seq = blk.blk_cksum.zc_word[ZIL_ZC_SEQ]; 338 int reclen; 339 char *end; 340 341 if (blk_seq > claim_blk_seq) 342 break; 343 if ((error = parse_blk_func(zilog, &blk, arg, txg)) != 0) 344 break; 345 ASSERT3U(max_blk_seq, <, blk_seq); 346 max_blk_seq = blk_seq; 347 blk_count++; 348 349 if (max_lr_seq == claim_lr_seq && max_blk_seq == claim_blk_seq) 350 break; 351 352 error = zil_read_log_block(zilog, &blk, &next_blk, lrbuf, &end); 353 if (error != 0) 354 break; 355 356 for (lrp = lrbuf; lrp < end; lrp += reclen) { 357 lr_t *lr = (lr_t *)lrp; 358 reclen = lr->lrc_reclen; 359 ASSERT3U(reclen, >=, sizeof (lr_t)); 360 if (lr->lrc_seq > claim_lr_seq) 361 goto done; 362 if ((error = parse_lr_func(zilog, lr, arg, txg)) != 0) 363 goto done; 364 ASSERT3U(max_lr_seq, <, lr->lrc_seq); 365 max_lr_seq = lr->lrc_seq; 366 lr_count++; 367 } 368 } 369done: 370 zilog->zl_parse_error = error; 371 zilog->zl_parse_blk_seq = max_blk_seq; 372 zilog->zl_parse_lr_seq = max_lr_seq; 373 zilog->zl_parse_blk_count = blk_count; 374 zilog->zl_parse_lr_count = lr_count; 375 376 ASSERT(!claimed || !(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID) || 377 (max_blk_seq == claim_blk_seq && max_lr_seq == claim_lr_seq)); 378 379 zil_bp_tree_fini(zilog); 380 zio_buf_free(lrbuf, SPA_OLD_MAXBLOCKSIZE); 381 382 return (error); 383} 384 385static int 386zil_claim_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t first_txg) 387{ 388 /* 389 * Claim log block if not already committed and not already claimed. 390 * If tx == NULL, just verify that the block is claimable. 391 */ 392 if (BP_IS_HOLE(bp) || bp->blk_birth < first_txg || 393 zil_bp_tree_add(zilog, bp) != 0) 394 return (0); 395 396 return (zio_wait(zio_claim(NULL, zilog->zl_spa, 397 tx == NULL ? 0 : first_txg, bp, spa_claim_notify, NULL, 398 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB))); 399} 400 401static int 402zil_claim_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t first_txg) 403{ 404 lr_write_t *lr = (lr_write_t *)lrc; 405 int error; 406 407 if (lrc->lrc_txtype != TX_WRITE) 408 return (0); 409 410 /* 411 * If the block is not readable, don't claim it. This can happen 412 * in normal operation when a log block is written to disk before 413 * some of the dmu_sync() blocks it points to. In this case, the 414 * transaction cannot have been committed to anyone (we would have 415 * waited for all writes to be stable first), so it is semantically 416 * correct to declare this the end of the log. 417 */ 418 if (lr->lr_blkptr.blk_birth >= first_txg && 419 (error = zil_read_log_data(zilog, lr, NULL)) != 0) 420 return (error); 421 return (zil_claim_log_block(zilog, &lr->lr_blkptr, tx, first_txg)); 422} 423 424/* ARGSUSED */ 425static int 426zil_free_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t claim_txg) 427{ 428 zio_free_zil(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 429 430 return (0); 431} 432 433static int 434zil_free_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t claim_txg) 435{ 436 lr_write_t *lr = (lr_write_t *)lrc; 437 blkptr_t *bp = &lr->lr_blkptr; 438 439 /* 440 * If we previously claimed it, we need to free it. 441 */ 442 if (claim_txg != 0 && lrc->lrc_txtype == TX_WRITE && 443 bp->blk_birth >= claim_txg && zil_bp_tree_add(zilog, bp) == 0 && 444 !BP_IS_HOLE(bp)) 445 zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 446 447 return (0); 448} 449 450static lwb_t * 451zil_alloc_lwb(zilog_t *zilog, blkptr_t *bp, uint64_t txg) 452{ 453 lwb_t *lwb; 454 455 lwb = kmem_cache_alloc(zil_lwb_cache, KM_SLEEP); 456 lwb->lwb_zilog = zilog; 457 lwb->lwb_blk = *bp; 458 lwb->lwb_buf = zio_buf_alloc(BP_GET_LSIZE(bp)); 459 lwb->lwb_max_txg = txg; 460 lwb->lwb_zio = NULL; 461 lwb->lwb_tx = NULL; 462 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 463 lwb->lwb_nused = sizeof (zil_chain_t); 464 lwb->lwb_sz = BP_GET_LSIZE(bp); 465 } else { 466 lwb->lwb_nused = 0; 467 lwb->lwb_sz = BP_GET_LSIZE(bp) - sizeof (zil_chain_t); 468 } 469 470 mutex_enter(&zilog->zl_lock); 471 list_insert_tail(&zilog->zl_lwb_list, lwb); 472 mutex_exit(&zilog->zl_lock); 473 474 return (lwb); 475} 476 477/* 478 * Called when we create in-memory log transactions so that we know 479 * to cleanup the itxs at the end of spa_sync(). 480 */ 481void 482zilog_dirty(zilog_t *zilog, uint64_t txg) 483{ 484 dsl_pool_t *dp = zilog->zl_dmu_pool; 485 dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); 486 487 if (ds->ds_is_snapshot) 488 panic("dirtying snapshot!"); 489 490 if (txg_list_add(&dp->dp_dirty_zilogs, zilog, txg)) { 491 /* up the hold count until we can be written out */ 492 dmu_buf_add_ref(ds->ds_dbuf, zilog); 493 } 494} 495 496boolean_t 497zilog_is_dirty(zilog_t *zilog) 498{ 499 dsl_pool_t *dp = zilog->zl_dmu_pool; 500 501 for (int t = 0; t < TXG_SIZE; t++) { 502 if (txg_list_member(&dp->dp_dirty_zilogs, zilog, t)) 503 return (B_TRUE); 504 } 505 return (B_FALSE); 506} 507 508/* 509 * Create an on-disk intent log. 510 */ 511static lwb_t * 512zil_create(zilog_t *zilog) 513{ 514 const zil_header_t *zh = zilog->zl_header; 515 lwb_t *lwb = NULL; 516 uint64_t txg = 0; 517 dmu_tx_t *tx = NULL; 518 blkptr_t blk; 519 int error = 0; 520 521 /* 522 * Wait for any previous destroy to complete. 523 */ 524 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 525 526 ASSERT(zh->zh_claim_txg == 0); 527 ASSERT(zh->zh_replay_seq == 0); 528 529 blk = zh->zh_log; 530 531 /* 532 * Allocate an initial log block if: 533 * - there isn't one already 534 * - the existing block is the wrong endianess 535 */ 536 if (BP_IS_HOLE(&blk) || BP_SHOULD_BYTESWAP(&blk)) { 537 tx = dmu_tx_create(zilog->zl_os); 538 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 539 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 540 txg = dmu_tx_get_txg(tx); 541 542 if (!BP_IS_HOLE(&blk)) { 543 zio_free_zil(zilog->zl_spa, txg, &blk); 544 BP_ZERO(&blk); 545 } 546 547 error = zio_alloc_zil(zilog->zl_spa, txg, &blk, NULL, 548 ZIL_MIN_BLKSZ, zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 549 550 if (error == 0) 551 zil_init_log_chain(zilog, &blk); 552 } 553 554 /* 555 * Allocate a log write buffer (lwb) for the first log block. 556 */ 557 if (error == 0) 558 lwb = zil_alloc_lwb(zilog, &blk, txg); 559 560 /* 561 * If we just allocated the first log block, commit our transaction 562 * and wait for zil_sync() to stuff the block poiner into zh_log. 563 * (zh is part of the MOS, so we cannot modify it in open context.) 564 */ 565 if (tx != NULL) { 566 dmu_tx_commit(tx); 567 txg_wait_synced(zilog->zl_dmu_pool, txg); 568 } 569 570 ASSERT(bcmp(&blk, &zh->zh_log, sizeof (blk)) == 0); 571 572 return (lwb); 573} 574 575/* 576 * In one tx, free all log blocks and clear the log header. 577 * If keep_first is set, then we're replaying a log with no content. 578 * We want to keep the first block, however, so that the first 579 * synchronous transaction doesn't require a txg_wait_synced() 580 * in zil_create(). We don't need to txg_wait_synced() here either 581 * when keep_first is set, because both zil_create() and zil_destroy() 582 * will wait for any in-progress destroys to complete. 583 */ 584void 585zil_destroy(zilog_t *zilog, boolean_t keep_first) 586{ 587 const zil_header_t *zh = zilog->zl_header; 588 lwb_t *lwb; 589 dmu_tx_t *tx; 590 uint64_t txg; 591 592 /* 593 * Wait for any previous destroy to complete. 594 */ 595 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 596 597 zilog->zl_old_header = *zh; /* debugging aid */ 598 599 if (BP_IS_HOLE(&zh->zh_log)) 600 return; 601 602 tx = dmu_tx_create(zilog->zl_os); 603 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 604 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 605 txg = dmu_tx_get_txg(tx); 606 607 mutex_enter(&zilog->zl_lock); 608 609 ASSERT3U(zilog->zl_destroy_txg, <, txg); 610 zilog->zl_destroy_txg = txg; 611 zilog->zl_keep_first = keep_first; 612 613 if (!list_is_empty(&zilog->zl_lwb_list)) { 614 ASSERT(zh->zh_claim_txg == 0); 615 VERIFY(!keep_first); 616 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 617 list_remove(&zilog->zl_lwb_list, lwb); 618 if (lwb->lwb_buf != NULL) 619 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 620 zio_free_zil(zilog->zl_spa, txg, &lwb->lwb_blk); 621 kmem_cache_free(zil_lwb_cache, lwb); 622 } 623 } else if (!keep_first) { 624 zil_destroy_sync(zilog, tx); 625 } 626 mutex_exit(&zilog->zl_lock); 627 628 dmu_tx_commit(tx); 629} 630 631void 632zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx) 633{ 634 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 635 (void) zil_parse(zilog, zil_free_log_block, 636 zil_free_log_record, tx, zilog->zl_header->zh_claim_txg); 637} 638 639int 640zil_claim(dsl_pool_t *dp, dsl_dataset_t *ds, void *txarg) 641{ 642 dmu_tx_t *tx = txarg; 643 uint64_t first_txg = dmu_tx_get_txg(tx); 644 zilog_t *zilog; 645 zil_header_t *zh; 646 objset_t *os; 647 int error; 648 649 error = dmu_objset_own_obj(dp, ds->ds_object, 650 DMU_OST_ANY, B_FALSE, FTAG, &os); 651 if (error != 0) { 652 /* 653 * EBUSY indicates that the objset is inconsistent, in which 654 * case it can not have a ZIL. 655 */ 656 if (error != EBUSY) { 657 cmn_err(CE_WARN, "can't open objset for %llu, error %u", 658 (unsigned long long)ds->ds_object, error); 659 } 660 return (0); 661 } 662 663 zilog = dmu_objset_zil(os); 664 zh = zil_header_in_syncing_context(zilog); 665 666 if (spa_get_log_state(zilog->zl_spa) == SPA_LOG_CLEAR) { 667 if (!BP_IS_HOLE(&zh->zh_log)) 668 zio_free_zil(zilog->zl_spa, first_txg, &zh->zh_log); 669 BP_ZERO(&zh->zh_log); 670 dsl_dataset_dirty(dmu_objset_ds(os), tx); 671 dmu_objset_disown(os, FTAG); 672 return (0); 673 } 674 675 /* 676 * Claim all log blocks if we haven't already done so, and remember 677 * the highest claimed sequence number. This ensures that if we can 678 * read only part of the log now (e.g. due to a missing device), 679 * but we can read the entire log later, we will not try to replay 680 * or destroy beyond the last block we successfully claimed. 681 */ 682 ASSERT3U(zh->zh_claim_txg, <=, first_txg); 683 if (zh->zh_claim_txg == 0 && !BP_IS_HOLE(&zh->zh_log)) { 684 (void) zil_parse(zilog, zil_claim_log_block, 685 zil_claim_log_record, tx, first_txg); 686 zh->zh_claim_txg = first_txg; 687 zh->zh_claim_blk_seq = zilog->zl_parse_blk_seq; 688 zh->zh_claim_lr_seq = zilog->zl_parse_lr_seq; 689 if (zilog->zl_parse_lr_count || zilog->zl_parse_blk_count > 1) 690 zh->zh_flags |= ZIL_REPLAY_NEEDED; 691 zh->zh_flags |= ZIL_CLAIM_LR_SEQ_VALID; 692 dsl_dataset_dirty(dmu_objset_ds(os), tx); 693 } 694 695 ASSERT3U(first_txg, ==, (spa_last_synced_txg(zilog->zl_spa) + 1)); 696 dmu_objset_disown(os, FTAG); 697 return (0); 698} 699 700/* 701 * Check the log by walking the log chain. 702 * Checksum errors are ok as they indicate the end of the chain. 703 * Any other error (no device or read failure) returns an error. 704 */ 705/* ARGSUSED */ 706int 707zil_check_log_chain(dsl_pool_t *dp, dsl_dataset_t *ds, void *tx) 708{ 709 zilog_t *zilog; 710 objset_t *os; 711 blkptr_t *bp; 712 int error; 713 714 ASSERT(tx == NULL); 715 716 error = dmu_objset_from_ds(ds, &os); 717 if (error != 0) { 718 cmn_err(CE_WARN, "can't open objset %llu, error %d", 719 (unsigned long long)ds->ds_object, error); 720 return (0); 721 } 722 723 zilog = dmu_objset_zil(os); 724 bp = (blkptr_t *)&zilog->zl_header->zh_log; 725 726 /* 727 * Check the first block and determine if it's on a log device 728 * which may have been removed or faulted prior to loading this 729 * pool. If so, there's no point in checking the rest of the log 730 * as its content should have already been synced to the pool. 731 */ 732 if (!BP_IS_HOLE(bp)) { 733 vdev_t *vd; 734 boolean_t valid = B_TRUE; 735 736 spa_config_enter(os->os_spa, SCL_STATE, FTAG, RW_READER); 737 vd = vdev_lookup_top(os->os_spa, DVA_GET_VDEV(&bp->blk_dva[0])); 738 if (vd->vdev_islog && vdev_is_dead(vd)) 739 valid = vdev_log_state_valid(vd); 740 spa_config_exit(os->os_spa, SCL_STATE, FTAG); 741 742 if (!valid) 743 return (0); 744 } 745 746 /* 747 * Because tx == NULL, zil_claim_log_block() will not actually claim 748 * any blocks, but just determine whether it is possible to do so. 749 * In addition to checking the log chain, zil_claim_log_block() 750 * will invoke zio_claim() with a done func of spa_claim_notify(), 751 * which will update spa_max_claim_txg. See spa_load() for details. 752 */ 753 error = zil_parse(zilog, zil_claim_log_block, zil_claim_log_record, tx, 754 zilog->zl_header->zh_claim_txg ? -1ULL : spa_first_txg(os->os_spa)); 755 756 return ((error == ECKSUM || error == ENOENT) ? 0 : error); 757} 758 759static int 760zil_vdev_compare(const void *x1, const void *x2) 761{ 762 const uint64_t v1 = ((zil_vdev_node_t *)x1)->zv_vdev; 763 const uint64_t v2 = ((zil_vdev_node_t *)x2)->zv_vdev; 764 765 if (v1 < v2) 766 return (-1); 767 if (v1 > v2) 768 return (1); 769 770 return (0); 771} 772 773void 774zil_add_block(zilog_t *zilog, const blkptr_t *bp) 775{ 776 avl_tree_t *t = &zilog->zl_vdev_tree; 777 avl_index_t where; 778 zil_vdev_node_t *zv, zvsearch; 779 int ndvas = BP_GET_NDVAS(bp); 780 int i; 781 782 if (zfs_nocacheflush) 783 return; 784 785 ASSERT(zilog->zl_writer); 786 787 /* 788 * Even though we're zl_writer, we still need a lock because the 789 * zl_get_data() callbacks may have dmu_sync() done callbacks 790 * that will run concurrently. 791 */ 792 mutex_enter(&zilog->zl_vdev_lock); 793 for (i = 0; i < ndvas; i++) { 794 zvsearch.zv_vdev = DVA_GET_VDEV(&bp->blk_dva[i]); 795 if (avl_find(t, &zvsearch, &where) == NULL) { 796 zv = kmem_alloc(sizeof (*zv), KM_SLEEP); 797 zv->zv_vdev = zvsearch.zv_vdev; 798 avl_insert(t, zv, where); 799 } 800 } 801 mutex_exit(&zilog->zl_vdev_lock); 802} 803 804static void 805zil_flush_vdevs(zilog_t *zilog) 806{ 807 spa_t *spa = zilog->zl_spa; 808 avl_tree_t *t = &zilog->zl_vdev_tree; 809 void *cookie = NULL; 810 zil_vdev_node_t *zv; 811 zio_t *zio; 812 813 ASSERT(zilog->zl_writer); 814 815 /* 816 * We don't need zl_vdev_lock here because we're the zl_writer, 817 * and all zl_get_data() callbacks are done. 818 */ 819 if (avl_numnodes(t) == 0) 820 return; 821 822 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 823 824 zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL); 825 826 while ((zv = avl_destroy_nodes(t, &cookie)) != NULL) { 827 vdev_t *vd = vdev_lookup_top(spa, zv->zv_vdev); 828 if (vd != NULL) 829 zio_flush(zio, vd); 830 kmem_free(zv, sizeof (*zv)); 831 } 832 833 /* 834 * Wait for all the flushes to complete. Not all devices actually 835 * support the DKIOCFLUSHWRITECACHE ioctl, so it's OK if it fails. 836 */ 837 (void) zio_wait(zio); 838 839 spa_config_exit(spa, SCL_STATE, FTAG); 840} 841 842/* 843 * Function called when a log block write completes 844 */ 845static void 846zil_lwb_write_done(zio_t *zio) 847{ 848 lwb_t *lwb = zio->io_private; 849 zilog_t *zilog = lwb->lwb_zilog; 850 dmu_tx_t *tx = lwb->lwb_tx; 851 852 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); 853 ASSERT(BP_GET_TYPE(zio->io_bp) == DMU_OT_INTENT_LOG); 854 ASSERT(BP_GET_LEVEL(zio->io_bp) == 0); 855 ASSERT(BP_GET_BYTEORDER(zio->io_bp) == ZFS_HOST_BYTEORDER); 856 ASSERT(!BP_IS_GANG(zio->io_bp)); 857 ASSERT(!BP_IS_HOLE(zio->io_bp)); 858 ASSERT(BP_GET_FILL(zio->io_bp) == 0); 859 860 /* 861 * Ensure the lwb buffer pointer is cleared before releasing 862 * the txg. If we have had an allocation failure and 863 * the txg is waiting to sync then we want want zil_sync() 864 * to remove the lwb so that it's not picked up as the next new 865 * one in zil_commit_writer(). zil_sync() will only remove 866 * the lwb if lwb_buf is null. 867 */ 868 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 869 mutex_enter(&zilog->zl_lock); 870 lwb->lwb_buf = NULL; 871 lwb->lwb_tx = NULL; 872 mutex_exit(&zilog->zl_lock); 873 874 /* 875 * Now that we've written this log block, we have a stable pointer 876 * to the next block in the chain, so it's OK to let the txg in 877 * which we allocated the next block sync. 878 */ 879 dmu_tx_commit(tx); 880} 881 882/* 883 * Initialize the io for a log block. 884 */ 885static void 886zil_lwb_write_init(zilog_t *zilog, lwb_t *lwb) 887{ 888 zbookmark_phys_t zb; 889 890 SET_BOOKMARK(&zb, lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_OBJSET], 891 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, 892 lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_SEQ]); 893 894 if (zilog->zl_root_zio == NULL) { 895 zilog->zl_root_zio = zio_root(zilog->zl_spa, NULL, NULL, 896 ZIO_FLAG_CANFAIL); 897 } 898 if (lwb->lwb_zio == NULL) { 899 lwb->lwb_zio = zio_rewrite(zilog->zl_root_zio, zilog->zl_spa, 900 0, &lwb->lwb_blk, lwb->lwb_buf, BP_GET_LSIZE(&lwb->lwb_blk), 901 zil_lwb_write_done, lwb, ZIO_PRIORITY_SYNC_WRITE, 902 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE, &zb); 903 } 904} 905 906/* 907 * Define a limited set of intent log block sizes. 908 * 909 * These must be a multiple of 4KB. Note only the amount used (again 910 * aligned to 4KB) actually gets written. However, we can't always just 911 * allocate SPA_OLD_MAXBLOCKSIZE as the slog space could be exhausted. 912 */ 913uint64_t zil_block_buckets[] = { 914 4096, /* non TX_WRITE */ 915 8192+4096, /* data base */ 916 32*1024 + 4096, /* NFS writes */ 917 UINT64_MAX 918}; 919 920/* 921 * Use the slog as long as the logbias is 'latency' and the current commit size 922 * is less than the limit or the total list size is less than 2X the limit. 923 * Limit checking is disabled by setting zil_slog_limit to UINT64_MAX. 924 */ 925uint64_t zil_slog_limit = 1024 * 1024; 926#define USE_SLOG(zilog) (((zilog)->zl_logbias == ZFS_LOGBIAS_LATENCY) && \ 927 (((zilog)->zl_cur_used < zil_slog_limit) || \ 928 ((zilog)->zl_itx_list_sz < (zil_slog_limit << 1)))) 929 930/* 931 * Start a log block write and advance to the next log block. 932 * Calls are serialized. 933 */ 934static lwb_t * 935zil_lwb_write_start(zilog_t *zilog, lwb_t *lwb) 936{ 937 lwb_t *nlwb = NULL; 938 zil_chain_t *zilc; 939 spa_t *spa = zilog->zl_spa; 940 blkptr_t *bp; 941 dmu_tx_t *tx; 942 uint64_t txg; 943 uint64_t zil_blksz, wsz; 944 int i, error; 945 946 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 947 zilc = (zil_chain_t *)lwb->lwb_buf; 948 bp = &zilc->zc_next_blk; 949 } else { 950 zilc = (zil_chain_t *)(lwb->lwb_buf + lwb->lwb_sz); 951 bp = &zilc->zc_next_blk; 952 } 953 954 ASSERT(lwb->lwb_nused <= lwb->lwb_sz); 955 956 /* 957 * Allocate the next block and save its address in this block 958 * before writing it in order to establish the log chain. 959 * Note that if the allocation of nlwb synced before we wrote 960 * the block that points at it (lwb), we'd leak it if we crashed. 961 * Therefore, we don't do dmu_tx_commit() until zil_lwb_write_done(). 962 * We dirty the dataset to ensure that zil_sync() will be called 963 * to clean up in the event of allocation failure or I/O failure. 964 */ 965 tx = dmu_tx_create(zilog->zl_os); 966 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 967 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 968 txg = dmu_tx_get_txg(tx); 969 970 lwb->lwb_tx = tx; 971 972 /* 973 * Log blocks are pre-allocated. Here we select the size of the next 974 * block, based on size used in the last block. 975 * - first find the smallest bucket that will fit the block from a 976 * limited set of block sizes. This is because it's faster to write 977 * blocks allocated from the same metaslab as they are adjacent or 978 * close. 979 * - next find the maximum from the new suggested size and an array of 980 * previous sizes. This lessens a picket fence effect of wrongly 981 * guesssing the size if we have a stream of say 2k, 64k, 2k, 64k 982 * requests. 983 * 984 * Note we only write what is used, but we can't just allocate 985 * the maximum block size because we can exhaust the available 986 * pool log space. 987 */ 988 zil_blksz = zilog->zl_cur_used + sizeof (zil_chain_t); 989 for (i = 0; zil_blksz > zil_block_buckets[i]; i++) 990 continue; 991 zil_blksz = zil_block_buckets[i]; 992 if (zil_blksz == UINT64_MAX) 993 zil_blksz = SPA_OLD_MAXBLOCKSIZE; 994 zilog->zl_prev_blks[zilog->zl_prev_rotor] = zil_blksz; 995 for (i = 0; i < ZIL_PREV_BLKS; i++) 996 zil_blksz = MAX(zil_blksz, zilog->zl_prev_blks[i]); 997 zilog->zl_prev_rotor = (zilog->zl_prev_rotor + 1) & (ZIL_PREV_BLKS - 1); 998 999 BP_ZERO(bp); 1000 /* pass the old blkptr in order to spread log blocks across devs */ 1001 error = zio_alloc_zil(spa, txg, bp, &lwb->lwb_blk, zil_blksz, 1002 USE_SLOG(zilog)); 1003 if (error == 0) { 1004 ASSERT3U(bp->blk_birth, ==, txg); 1005 bp->blk_cksum = lwb->lwb_blk.blk_cksum; 1006 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]++; 1007 1008 /* 1009 * Allocate a new log write buffer (lwb). 1010 */ 1011 nlwb = zil_alloc_lwb(zilog, bp, txg); 1012 1013 /* Record the block for later vdev flushing */ 1014 zil_add_block(zilog, &lwb->lwb_blk); 1015 } 1016 1017 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 1018 /* For Slim ZIL only write what is used. */ 1019 wsz = P2ROUNDUP_TYPED(lwb->lwb_nused, ZIL_MIN_BLKSZ, uint64_t); 1020 ASSERT3U(wsz, <=, lwb->lwb_sz); 1021 zio_shrink(lwb->lwb_zio, wsz); 1022 1023 } else { 1024 wsz = lwb->lwb_sz; 1025 } 1026 1027 zilc->zc_pad = 0; 1028 zilc->zc_nused = lwb->lwb_nused; 1029 zilc->zc_eck.zec_cksum = lwb->lwb_blk.blk_cksum; 1030 1031 /* 1032 * clear unused data for security 1033 */ 1034 bzero(lwb->lwb_buf + lwb->lwb_nused, wsz - lwb->lwb_nused); 1035 1036 zio_nowait(lwb->lwb_zio); /* Kick off the write for the old log block */ 1037 1038 /* 1039 * If there was an allocation failure then nlwb will be null which 1040 * forces a txg_wait_synced(). 1041 */ 1042 return (nlwb); 1043} 1044 1045static lwb_t * 1046zil_lwb_commit(zilog_t *zilog, itx_t *itx, lwb_t *lwb) 1047{ 1048 lr_t *lrc = &itx->itx_lr; /* common log record */ 1049 lr_write_t *lrw = (lr_write_t *)lrc; 1050 char *lr_buf; 1051 uint64_t txg = lrc->lrc_txg; 1052 uint64_t reclen = lrc->lrc_reclen; 1053 uint64_t dlen = 0; 1054 1055 if (lwb == NULL) 1056 return (NULL); 1057 1058 ASSERT(lwb->lwb_buf != NULL); 1059 ASSERT(zilog_is_dirty(zilog) || 1060 spa_freeze_txg(zilog->zl_spa) != UINT64_MAX); 1061 1062 if (lrc->lrc_txtype == TX_WRITE && itx->itx_wr_state == WR_NEED_COPY) 1063 dlen = P2ROUNDUP_TYPED( 1064 lrw->lr_length, sizeof (uint64_t), uint64_t); 1065 1066 zilog->zl_cur_used += (reclen + dlen); 1067 1068 zil_lwb_write_init(zilog, lwb); 1069 1070 /* 1071 * If this record won't fit in the current log block, start a new one. 1072 */ 1073 if (lwb->lwb_nused + reclen + dlen > lwb->lwb_sz) { 1074 lwb = zil_lwb_write_start(zilog, lwb); 1075 if (lwb == NULL) 1076 return (NULL); 1077 zil_lwb_write_init(zilog, lwb); 1078 ASSERT(LWB_EMPTY(lwb)); 1079 if (lwb->lwb_nused + reclen + dlen > lwb->lwb_sz) { 1080 txg_wait_synced(zilog->zl_dmu_pool, txg); 1081 return (lwb); 1082 } 1083 } 1084 1085 lr_buf = lwb->lwb_buf + lwb->lwb_nused; 1086 bcopy(lrc, lr_buf, reclen); 1087 lrc = (lr_t *)lr_buf; 1088 lrw = (lr_write_t *)lrc; 1089 1090 /* 1091 * If it's a write, fetch the data or get its blkptr as appropriate. 1092 */ 1093 if (lrc->lrc_txtype == TX_WRITE) { 1094 if (txg > spa_freeze_txg(zilog->zl_spa)) 1095 txg_wait_synced(zilog->zl_dmu_pool, txg); 1096 if (itx->itx_wr_state != WR_COPIED) { 1097 char *dbuf; 1098 int error; 1099 1100 if (dlen) { 1101 ASSERT(itx->itx_wr_state == WR_NEED_COPY); 1102 dbuf = lr_buf + reclen; 1103 lrw->lr_common.lrc_reclen += dlen; 1104 } else { 1105 ASSERT(itx->itx_wr_state == WR_INDIRECT); 1106 dbuf = NULL; 1107 } 1108 error = zilog->zl_get_data( 1109 itx->itx_private, lrw, dbuf, lwb->lwb_zio); 1110 if (error == EIO) { 1111 txg_wait_synced(zilog->zl_dmu_pool, txg); 1112 return (lwb); 1113 } 1114 if (error != 0) { 1115 ASSERT(error == ENOENT || error == EEXIST || 1116 error == EALREADY); 1117 return (lwb); 1118 } 1119 } 1120 } 1121 1122 /* 1123 * We're actually making an entry, so update lrc_seq to be the 1124 * log record sequence number. Note that this is generally not 1125 * equal to the itx sequence number because not all transactions 1126 * are synchronous, and sometimes spa_sync() gets there first. 1127 */ 1128 lrc->lrc_seq = ++zilog->zl_lr_seq; /* we are single threaded */ 1129 lwb->lwb_nused += reclen + dlen; 1130 lwb->lwb_max_txg = MAX(lwb->lwb_max_txg, txg); 1131 ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_sz); 1132 ASSERT0(P2PHASE(lwb->lwb_nused, sizeof (uint64_t))); 1133 1134 return (lwb); 1135} 1136 1137itx_t * 1138zil_itx_create(uint64_t txtype, size_t lrsize) 1139{ 1140 itx_t *itx; 1141 1142 lrsize = P2ROUNDUP_TYPED(lrsize, sizeof (uint64_t), size_t); 1143 1144 itx = kmem_alloc(offsetof(itx_t, itx_lr) + lrsize, KM_SLEEP); 1145 itx->itx_lr.lrc_txtype = txtype; 1146 itx->itx_lr.lrc_reclen = lrsize; 1147 itx->itx_sod = lrsize; /* if write & WR_NEED_COPY will be increased */ 1148 itx->itx_lr.lrc_seq = 0; /* defensive */ 1149 itx->itx_sync = B_TRUE; /* default is synchronous */ 1150 1151 return (itx); 1152} 1153 1154void 1155zil_itx_destroy(itx_t *itx) 1156{ 1157 kmem_free(itx, offsetof(itx_t, itx_lr) + itx->itx_lr.lrc_reclen); 1158} 1159 1160/* 1161 * Free up the sync and async itxs. The itxs_t has already been detached 1162 * so no locks are needed. 1163 */ 1164static void 1165zil_itxg_clean(itxs_t *itxs) 1166{ 1167 itx_t *itx; 1168 list_t *list; 1169 avl_tree_t *t; 1170 void *cookie; 1171 itx_async_node_t *ian; 1172 1173 list = &itxs->i_sync_list; 1174 while ((itx = list_head(list)) != NULL) { 1175 list_remove(list, itx); 1176 kmem_free(itx, offsetof(itx_t, itx_lr) + 1177 itx->itx_lr.lrc_reclen); 1178 } 1179 1180 cookie = NULL; 1181 t = &itxs->i_async_tree; 1182 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1183 list = &ian->ia_list; 1184 while ((itx = list_head(list)) != NULL) { 1185 list_remove(list, itx); 1186 kmem_free(itx, offsetof(itx_t, itx_lr) + 1187 itx->itx_lr.lrc_reclen); 1188 } 1189 list_destroy(list); 1190 kmem_free(ian, sizeof (itx_async_node_t)); 1191 } 1192 avl_destroy(t); 1193 1194 kmem_free(itxs, sizeof (itxs_t)); 1195} 1196 1197static int 1198zil_aitx_compare(const void *x1, const void *x2) 1199{ 1200 const uint64_t o1 = ((itx_async_node_t *)x1)->ia_foid; 1201 const uint64_t o2 = ((itx_async_node_t *)x2)->ia_foid; 1202 1203 if (o1 < o2) 1204 return (-1); 1205 if (o1 > o2) 1206 return (1); 1207 1208 return (0); 1209} 1210 1211/* 1212 * Remove all async itx with the given oid. 1213 */ 1214static void 1215zil_remove_async(zilog_t *zilog, uint64_t oid) 1216{ 1217 uint64_t otxg, txg; 1218 itx_async_node_t *ian; 1219 avl_tree_t *t; 1220 avl_index_t where; 1221 list_t clean_list; 1222 itx_t *itx; 1223 1224 ASSERT(oid != 0); 1225 list_create(&clean_list, sizeof (itx_t), offsetof(itx_t, itx_node)); 1226 1227 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1228 otxg = ZILTEST_TXG; 1229 else 1230 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1231 1232 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1233 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1234 1235 mutex_enter(&itxg->itxg_lock); 1236 if (itxg->itxg_txg != txg) { 1237 mutex_exit(&itxg->itxg_lock); 1238 continue; 1239 } 1240 1241 /* 1242 * Locate the object node and append its list. 1243 */ 1244 t = &itxg->itxg_itxs->i_async_tree; 1245 ian = avl_find(t, &oid, &where); 1246 if (ian != NULL) 1247 list_move_tail(&clean_list, &ian->ia_list); 1248 mutex_exit(&itxg->itxg_lock); 1249 } 1250 while ((itx = list_head(&clean_list)) != NULL) { 1251 list_remove(&clean_list, itx); 1252 kmem_free(itx, offsetof(itx_t, itx_lr) + 1253 itx->itx_lr.lrc_reclen); 1254 } 1255 list_destroy(&clean_list); 1256} 1257 1258void 1259zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx) 1260{ 1261 uint64_t txg; 1262 itxg_t *itxg; 1263 itxs_t *itxs, *clean = NULL; 1264 1265 /* 1266 * Object ids can be re-instantiated in the next txg so 1267 * remove any async transactions to avoid future leaks. 1268 * This can happen if a fsync occurs on the re-instantiated 1269 * object for a WR_INDIRECT or WR_NEED_COPY write, which gets 1270 * the new file data and flushes a write record for the old object. 1271 */ 1272 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_REMOVE) 1273 zil_remove_async(zilog, itx->itx_oid); 1274 1275 /* 1276 * Ensure the data of a renamed file is committed before the rename. 1277 */ 1278 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_RENAME) 1279 zil_async_to_sync(zilog, itx->itx_oid); 1280 1281 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) 1282 txg = ZILTEST_TXG; 1283 else 1284 txg = dmu_tx_get_txg(tx); 1285 1286 itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1287 mutex_enter(&itxg->itxg_lock); 1288 itxs = itxg->itxg_itxs; 1289 if (itxg->itxg_txg != txg) { 1290 if (itxs != NULL) { 1291 /* 1292 * The zil_clean callback hasn't got around to cleaning 1293 * this itxg. Save the itxs for release below. 1294 * This should be rare. 1295 */ 1296 atomic_add_64(&zilog->zl_itx_list_sz, -itxg->itxg_sod); 1297 itxg->itxg_sod = 0; 1298 clean = itxg->itxg_itxs; 1299 } 1300 ASSERT(itxg->itxg_sod == 0); 1301 itxg->itxg_txg = txg; 1302 itxs = itxg->itxg_itxs = kmem_zalloc(sizeof (itxs_t), KM_SLEEP); 1303 1304 list_create(&itxs->i_sync_list, sizeof (itx_t), 1305 offsetof(itx_t, itx_node)); 1306 avl_create(&itxs->i_async_tree, zil_aitx_compare, 1307 sizeof (itx_async_node_t), 1308 offsetof(itx_async_node_t, ia_node)); 1309 } 1310 if (itx->itx_sync) { 1311 list_insert_tail(&itxs->i_sync_list, itx); 1312 atomic_add_64(&zilog->zl_itx_list_sz, itx->itx_sod); 1313 itxg->itxg_sod += itx->itx_sod; 1314 } else { 1315 avl_tree_t *t = &itxs->i_async_tree; 1316 uint64_t foid = ((lr_ooo_t *)&itx->itx_lr)->lr_foid; 1317 itx_async_node_t *ian; 1318 avl_index_t where; 1319 1320 ian = avl_find(t, &foid, &where); 1321 if (ian == NULL) { 1322 ian = kmem_alloc(sizeof (itx_async_node_t), KM_SLEEP); 1323 list_create(&ian->ia_list, sizeof (itx_t), 1324 offsetof(itx_t, itx_node)); 1325 ian->ia_foid = foid; 1326 avl_insert(t, ian, where); 1327 } 1328 list_insert_tail(&ian->ia_list, itx); 1329 } 1330 1331 itx->itx_lr.lrc_txg = dmu_tx_get_txg(tx); 1332 zilog_dirty(zilog, txg); 1333 mutex_exit(&itxg->itxg_lock); 1334 1335 /* Release the old itxs now we've dropped the lock */ 1336 if (clean != NULL) 1337 zil_itxg_clean(clean); 1338} 1339 1340/* 1341 * If there are any in-memory intent log transactions which have now been 1342 * synced then start up a taskq to free them. We should only do this after we 1343 * have written out the uberblocks (i.e. txg has been comitted) so that 1344 * don't inadvertently clean out in-memory log records that would be required 1345 * by zil_commit(). 1346 */ 1347void 1348zil_clean(zilog_t *zilog, uint64_t synced_txg) 1349{ 1350 itxg_t *itxg = &zilog->zl_itxg[synced_txg & TXG_MASK]; 1351 itxs_t *clean_me; 1352 1353 mutex_enter(&itxg->itxg_lock); 1354 if (itxg->itxg_itxs == NULL || itxg->itxg_txg == ZILTEST_TXG) { 1355 mutex_exit(&itxg->itxg_lock); 1356 return; 1357 } 1358 ASSERT3U(itxg->itxg_txg, <=, synced_txg); 1359 ASSERT(itxg->itxg_txg != 0); 1360 ASSERT(zilog->zl_clean_taskq != NULL); 1361 atomic_add_64(&zilog->zl_itx_list_sz, -itxg->itxg_sod); 1362 itxg->itxg_sod = 0; 1363 clean_me = itxg->itxg_itxs; 1364 itxg->itxg_itxs = NULL; 1365 itxg->itxg_txg = 0; 1366 mutex_exit(&itxg->itxg_lock); 1367 /* 1368 * Preferably start a task queue to free up the old itxs but 1369 * if taskq_dispatch can't allocate resources to do that then 1370 * free it in-line. This should be rare. Note, using TQ_SLEEP 1371 * created a bad performance problem. 1372 */ 1373 if (taskq_dispatch(zilog->zl_clean_taskq, 1374 (void (*)(void *))zil_itxg_clean, clean_me, TQ_NOSLEEP) == 0) 1375 zil_itxg_clean(clean_me); 1376} 1377 1378/* 1379 * Get the list of itxs to commit into zl_itx_commit_list. 1380 */ 1381static void 1382zil_get_commit_list(zilog_t *zilog) 1383{ 1384 uint64_t otxg, txg; 1385 list_t *commit_list = &zilog->zl_itx_commit_list; 1386 uint64_t push_sod = 0; 1387 1388 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1389 otxg = ZILTEST_TXG; 1390 else 1391 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1392 1393 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1394 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1395 1396 mutex_enter(&itxg->itxg_lock); 1397 if (itxg->itxg_txg != txg) { 1398 mutex_exit(&itxg->itxg_lock); 1399 continue; 1400 } 1401 1402 list_move_tail(commit_list, &itxg->itxg_itxs->i_sync_list); 1403 push_sod += itxg->itxg_sod; 1404 itxg->itxg_sod = 0; 1405 1406 mutex_exit(&itxg->itxg_lock); 1407 } 1408 atomic_add_64(&zilog->zl_itx_list_sz, -push_sod); 1409} 1410 1411/* 1412 * Move the async itxs for a specified object to commit into sync lists. 1413 */ 1414static void 1415zil_async_to_sync(zilog_t *zilog, uint64_t foid) 1416{ 1417 uint64_t otxg, txg; 1418 itx_async_node_t *ian; 1419 avl_tree_t *t; 1420 avl_index_t where; 1421 1422 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1423 otxg = ZILTEST_TXG; 1424 else 1425 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1426 1427 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1428 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1429 1430 mutex_enter(&itxg->itxg_lock); 1431 if (itxg->itxg_txg != txg) { 1432 mutex_exit(&itxg->itxg_lock); 1433 continue; 1434 } 1435 1436 /* 1437 * If a foid is specified then find that node and append its 1438 * list. Otherwise walk the tree appending all the lists 1439 * to the sync list. We add to the end rather than the 1440 * beginning to ensure the create has happened. 1441 */ 1442 t = &itxg->itxg_itxs->i_async_tree; 1443 if (foid != 0) { 1444 ian = avl_find(t, &foid, &where); 1445 if (ian != NULL) { 1446 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1447 &ian->ia_list); 1448 } 1449 } else { 1450 void *cookie = NULL; 1451 1452 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1453 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1454 &ian->ia_list); 1455 list_destroy(&ian->ia_list); 1456 kmem_free(ian, sizeof (itx_async_node_t)); 1457 } 1458 } 1459 mutex_exit(&itxg->itxg_lock); 1460 } 1461} 1462 1463static void 1464zil_commit_writer(zilog_t *zilog) 1465{ 1466 uint64_t txg; 1467 itx_t *itx; 1468 lwb_t *lwb; 1469 spa_t *spa = zilog->zl_spa; 1470 int error = 0; 1471 1472 ASSERT(zilog->zl_root_zio == NULL); 1473 1474 mutex_exit(&zilog->zl_lock); 1475 1476 zil_get_commit_list(zilog); 1477 1478 /* 1479 * Return if there's nothing to commit before we dirty the fs by 1480 * calling zil_create(). 1481 */ 1482 if (list_head(&zilog->zl_itx_commit_list) == NULL) { 1483 mutex_enter(&zilog->zl_lock); 1484 return; 1485 } 1486 1487 if (zilog->zl_suspend) { 1488 lwb = NULL; 1489 } else { 1490 lwb = list_tail(&zilog->zl_lwb_list); 1491 if (lwb == NULL) 1492 lwb = zil_create(zilog); 1493 } 1494 1495 DTRACE_PROBE1(zil__cw1, zilog_t *, zilog); 1496 while (itx = list_head(&zilog->zl_itx_commit_list)) { 1497 txg = itx->itx_lr.lrc_txg; 1498 ASSERT(txg); 1499 1500 if (txg > spa_last_synced_txg(spa) || txg > spa_freeze_txg(spa)) 1501 lwb = zil_lwb_commit(zilog, itx, lwb); 1502 list_remove(&zilog->zl_itx_commit_list, itx); 1503 kmem_free(itx, offsetof(itx_t, itx_lr) 1504 + itx->itx_lr.lrc_reclen); 1505 } 1506 DTRACE_PROBE1(zil__cw2, zilog_t *, zilog); 1507 1508 /* write the last block out */ 1509 if (lwb != NULL && lwb->lwb_zio != NULL) 1510 lwb = zil_lwb_write_start(zilog, lwb); 1511 1512 zilog->zl_cur_used = 0; 1513 1514 /* 1515 * Wait if necessary for the log blocks to be on stable storage. 1516 */ 1517 if (zilog->zl_root_zio) { 1518 error = zio_wait(zilog->zl_root_zio); 1519 zilog->zl_root_zio = NULL; 1520 zil_flush_vdevs(zilog); 1521 } 1522 1523 if (error || lwb == NULL) 1524 txg_wait_synced(zilog->zl_dmu_pool, 0); 1525 1526 mutex_enter(&zilog->zl_lock); 1527 1528 /* 1529 * Remember the highest committed log sequence number for ztest. 1530 * We only update this value when all the log writes succeeded, 1531 * because ztest wants to ASSERT that it got the whole log chain. 1532 */ 1533 if (error == 0 && lwb != NULL) 1534 zilog->zl_commit_lr_seq = zilog->zl_lr_seq; 1535} 1536 1537/* 1538 * Commit zfs transactions to stable storage. 1539 * If foid is 0 push out all transactions, otherwise push only those 1540 * for that object or might reference that object. 1541 * 1542 * itxs are committed in batches. In a heavily stressed zil there will be 1543 * a commit writer thread who is writing out a bunch of itxs to the log 1544 * for a set of committing threads (cthreads) in the same batch as the writer. 1545 * Those cthreads are all waiting on the same cv for that batch. 1546 * 1547 * There will also be a different and growing batch of threads that are 1548 * waiting to commit (qthreads). When the committing batch completes 1549 * a transition occurs such that the cthreads exit and the qthreads become 1550 * cthreads. One of the new cthreads becomes the writer thread for the 1551 * batch. Any new threads arriving become new qthreads. 1552 * 1553 * Only 2 condition variables are needed and there's no transition 1554 * between the two cvs needed. They just flip-flop between qthreads 1555 * and cthreads. 1556 * 1557 * Using this scheme we can efficiently wakeup up only those threads 1558 * that have been committed. 1559 */ 1560void 1561zil_commit(zilog_t *zilog, uint64_t foid) 1562{ 1563 uint64_t mybatch; 1564 1565 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 1566 return; 1567 1568 /* move the async itxs for the foid to the sync queues */ 1569 zil_async_to_sync(zilog, foid); 1570 1571 mutex_enter(&zilog->zl_lock); 1572 mybatch = zilog->zl_next_batch; 1573 while (zilog->zl_writer) { 1574 cv_wait(&zilog->zl_cv_batch[mybatch & 1], &zilog->zl_lock); 1575 if (mybatch <= zilog->zl_com_batch) { 1576 mutex_exit(&zilog->zl_lock); 1577 return; 1578 } 1579 } 1580 1581 zilog->zl_next_batch++; 1582 zilog->zl_writer = B_TRUE; 1583 zil_commit_writer(zilog); 1584 zilog->zl_com_batch = mybatch; 1585 zilog->zl_writer = B_FALSE; 1586 mutex_exit(&zilog->zl_lock); 1587 1588 /* wake up one thread to become the next writer */ 1589 cv_signal(&zilog->zl_cv_batch[(mybatch+1) & 1]); 1590 1591 /* wake up all threads waiting for this batch to be committed */ 1592 cv_broadcast(&zilog->zl_cv_batch[mybatch & 1]); 1593} 1594 1595/* 1596 * Called in syncing context to free committed log blocks and update log header. 1597 */ 1598void 1599zil_sync(zilog_t *zilog, dmu_tx_t *tx) 1600{ 1601 zil_header_t *zh = zil_header_in_syncing_context(zilog); 1602 uint64_t txg = dmu_tx_get_txg(tx); 1603 spa_t *spa = zilog->zl_spa; 1604 uint64_t *replayed_seq = &zilog->zl_replayed_seq[txg & TXG_MASK]; 1605 lwb_t *lwb; 1606 1607 /* 1608 * We don't zero out zl_destroy_txg, so make sure we don't try 1609 * to destroy it twice. 1610 */ 1611 if (spa_sync_pass(spa) != 1) 1612 return; 1613 1614 mutex_enter(&zilog->zl_lock); 1615 1616 ASSERT(zilog->zl_stop_sync == 0); 1617 1618 if (*replayed_seq != 0) { 1619 ASSERT(zh->zh_replay_seq < *replayed_seq); 1620 zh->zh_replay_seq = *replayed_seq; 1621 *replayed_seq = 0; 1622 } 1623 1624 if (zilog->zl_destroy_txg == txg) { 1625 blkptr_t blk = zh->zh_log; 1626 1627 ASSERT(list_head(&zilog->zl_lwb_list) == NULL); 1628 1629 bzero(zh, sizeof (zil_header_t)); 1630 bzero(zilog->zl_replayed_seq, sizeof (zilog->zl_replayed_seq)); 1631 1632 if (zilog->zl_keep_first) { 1633 /* 1634 * If this block was part of log chain that couldn't 1635 * be claimed because a device was missing during 1636 * zil_claim(), but that device later returns, 1637 * then this block could erroneously appear valid. 1638 * To guard against this, assign a new GUID to the new 1639 * log chain so it doesn't matter what blk points to. 1640 */ 1641 zil_init_log_chain(zilog, &blk); 1642 zh->zh_log = blk; 1643 } 1644 } 1645 1646 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 1647 zh->zh_log = lwb->lwb_blk; 1648 if (lwb->lwb_buf != NULL || lwb->lwb_max_txg > txg) 1649 break; 1650 list_remove(&zilog->zl_lwb_list, lwb); 1651 zio_free_zil(spa, txg, &lwb->lwb_blk); 1652 kmem_cache_free(zil_lwb_cache, lwb); 1653 1654 /* 1655 * If we don't have anything left in the lwb list then 1656 * we've had an allocation failure and we need to zero 1657 * out the zil_header blkptr so that we don't end 1658 * up freeing the same block twice. 1659 */ 1660 if (list_head(&zilog->zl_lwb_list) == NULL) 1661 BP_ZERO(&zh->zh_log); 1662 } 1663 mutex_exit(&zilog->zl_lock); 1664} 1665 1666void 1667zil_init(void) 1668{ 1669 zil_lwb_cache = kmem_cache_create("zil_lwb_cache", 1670 sizeof (struct lwb), 0, NULL, NULL, NULL, NULL, NULL, 0); 1671} 1672 1673void 1674zil_fini(void) 1675{ 1676 kmem_cache_destroy(zil_lwb_cache); 1677} 1678 1679void 1680zil_set_sync(zilog_t *zilog, uint64_t sync) 1681{ 1682 zilog->zl_sync = sync; 1683} 1684 1685void 1686zil_set_logbias(zilog_t *zilog, uint64_t logbias) 1687{ 1688 zilog->zl_logbias = logbias; 1689} 1690 1691zilog_t * 1692zil_alloc(objset_t *os, zil_header_t *zh_phys) 1693{ 1694 zilog_t *zilog; 1695 1696 zilog = kmem_zalloc(sizeof (zilog_t), KM_SLEEP); 1697 1698 zilog->zl_header = zh_phys; 1699 zilog->zl_os = os; 1700 zilog->zl_spa = dmu_objset_spa(os); 1701 zilog->zl_dmu_pool = dmu_objset_pool(os); 1702 zilog->zl_destroy_txg = TXG_INITIAL - 1; 1703 zilog->zl_logbias = dmu_objset_logbias(os); 1704 zilog->zl_sync = dmu_objset_syncprop(os); 1705 zilog->zl_next_batch = 1; 1706 1707 mutex_init(&zilog->zl_lock, NULL, MUTEX_DEFAULT, NULL); 1708 1709 for (int i = 0; i < TXG_SIZE; i++) { 1710 mutex_init(&zilog->zl_itxg[i].itxg_lock, NULL, 1711 MUTEX_DEFAULT, NULL); 1712 } 1713 1714 list_create(&zilog->zl_lwb_list, sizeof (lwb_t), 1715 offsetof(lwb_t, lwb_node)); 1716 1717 list_create(&zilog->zl_itx_commit_list, sizeof (itx_t), 1718 offsetof(itx_t, itx_node)); 1719 1720 mutex_init(&zilog->zl_vdev_lock, NULL, MUTEX_DEFAULT, NULL); 1721 1722 avl_create(&zilog->zl_vdev_tree, zil_vdev_compare, 1723 sizeof (zil_vdev_node_t), offsetof(zil_vdev_node_t, zv_node)); 1724 1725 cv_init(&zilog->zl_cv_writer, NULL, CV_DEFAULT, NULL); 1726 cv_init(&zilog->zl_cv_suspend, NULL, CV_DEFAULT, NULL); 1727 cv_init(&zilog->zl_cv_batch[0], NULL, CV_DEFAULT, NULL); 1728 cv_init(&zilog->zl_cv_batch[1], NULL, CV_DEFAULT, NULL); 1729 1730 return (zilog); 1731} 1732 1733void 1734zil_free(zilog_t *zilog) 1735{ 1736 zilog->zl_stop_sync = 1; 1737 1738 ASSERT0(zilog->zl_suspend); 1739 ASSERT0(zilog->zl_suspending); 1740 1741 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1742 list_destroy(&zilog->zl_lwb_list); 1743 1744 avl_destroy(&zilog->zl_vdev_tree); 1745 mutex_destroy(&zilog->zl_vdev_lock); 1746 1747 ASSERT(list_is_empty(&zilog->zl_itx_commit_list)); 1748 list_destroy(&zilog->zl_itx_commit_list); 1749 1750 for (int i = 0; i < TXG_SIZE; i++) { 1751 /* 1752 * It's possible for an itx to be generated that doesn't dirty 1753 * a txg (e.g. ztest TX_TRUNCATE). So there's no zil_clean() 1754 * callback to remove the entry. We remove those here. 1755 * 1756 * Also free up the ziltest itxs. 1757 */ 1758 if (zilog->zl_itxg[i].itxg_itxs) 1759 zil_itxg_clean(zilog->zl_itxg[i].itxg_itxs); 1760 mutex_destroy(&zilog->zl_itxg[i].itxg_lock); 1761 } 1762 1763 mutex_destroy(&zilog->zl_lock); 1764 1765 cv_destroy(&zilog->zl_cv_writer); 1766 cv_destroy(&zilog->zl_cv_suspend); 1767 cv_destroy(&zilog->zl_cv_batch[0]); 1768 cv_destroy(&zilog->zl_cv_batch[1]); 1769 1770 kmem_free(zilog, sizeof (zilog_t)); 1771} 1772 1773/* 1774 * Open an intent log. 1775 */ 1776zilog_t * 1777zil_open(objset_t *os, zil_get_data_t *get_data) 1778{ 1779 zilog_t *zilog = dmu_objset_zil(os); 1780 1781 ASSERT(zilog->zl_clean_taskq == NULL); 1782 ASSERT(zilog->zl_get_data == NULL); 1783 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1784 1785 zilog->zl_get_data = get_data; 1786 zilog->zl_clean_taskq = taskq_create("zil_clean", 1, minclsyspri, 1787 2, 2, TASKQ_PREPOPULATE); 1788 1789 return (zilog); 1790} 1791 1792/* 1793 * Close an intent log. 1794 */ 1795void 1796zil_close(zilog_t *zilog) 1797{ 1798 lwb_t *lwb; 1799 uint64_t txg = 0; 1800 1801 zil_commit(zilog, 0); /* commit all itx */ 1802 1803 /* 1804 * The lwb_max_txg for the stubby lwb will reflect the last activity 1805 * for the zil. After a txg_wait_synced() on the txg we know all the 1806 * callbacks have occurred that may clean the zil. Only then can we 1807 * destroy the zl_clean_taskq. 1808 */ 1809 mutex_enter(&zilog->zl_lock); 1810 lwb = list_tail(&zilog->zl_lwb_list); 1811 if (lwb != NULL) 1812 txg = lwb->lwb_max_txg; 1813 mutex_exit(&zilog->zl_lock); 1814 if (txg) 1815 txg_wait_synced(zilog->zl_dmu_pool, txg); 1816 ASSERT(!zilog_is_dirty(zilog)); 1817 1818 taskq_destroy(zilog->zl_clean_taskq); 1819 zilog->zl_clean_taskq = NULL; 1820 zilog->zl_get_data = NULL; 1821 1822 /* 1823 * We should have only one LWB left on the list; remove it now. 1824 */ 1825 mutex_enter(&zilog->zl_lock); 1826 lwb = list_head(&zilog->zl_lwb_list); 1827 if (lwb != NULL) { 1828 ASSERT(lwb == list_tail(&zilog->zl_lwb_list)); 1829 list_remove(&zilog->zl_lwb_list, lwb); 1830 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 1831 kmem_cache_free(zil_lwb_cache, lwb); 1832 } 1833 mutex_exit(&zilog->zl_lock); 1834} 1835 1836static char *suspend_tag = "zil suspending"; 1837 1838/* 1839 * Suspend an intent log. While in suspended mode, we still honor 1840 * synchronous semantics, but we rely on txg_wait_synced() to do it. 1841 * On old version pools, we suspend the log briefly when taking a 1842 * snapshot so that it will have an empty intent log. 1843 * 1844 * Long holds are not really intended to be used the way we do here -- 1845 * held for such a short time. A concurrent caller of dsl_dataset_long_held() 1846 * could fail. Therefore we take pains to only put a long hold if it is 1847 * actually necessary. Fortunately, it will only be necessary if the 1848 * objset is currently mounted (or the ZVOL equivalent). In that case it 1849 * will already have a long hold, so we are not really making things any worse. 1850 * 1851 * Ideally, we would locate the existing long-holder (i.e. the zfsvfs_t or 1852 * zvol_state_t), and use their mechanism to prevent their hold from being 1853 * dropped (e.g. VFS_HOLD()). However, that would be even more pain for 1854 * very little gain. 1855 * 1856 * if cookiep == NULL, this does both the suspend & resume. 1857 * Otherwise, it returns with the dataset "long held", and the cookie 1858 * should be passed into zil_resume(). 1859 */ 1860int 1861zil_suspend(const char *osname, void **cookiep) 1862{ 1863 objset_t *os; 1864 zilog_t *zilog; 1865 const zil_header_t *zh; 1866 int error; 1867 1868 error = dmu_objset_hold(osname, suspend_tag, &os); 1869 if (error != 0) 1870 return (error); 1871 zilog = dmu_objset_zil(os); 1872 1873 mutex_enter(&zilog->zl_lock); 1874 zh = zilog->zl_header; 1875 1876 if (zh->zh_flags & ZIL_REPLAY_NEEDED) { /* unplayed log */ 1877 mutex_exit(&zilog->zl_lock); 1878 dmu_objset_rele(os, suspend_tag); 1879 return (SET_ERROR(EBUSY)); 1880 } 1881 1882 /* 1883 * Don't put a long hold in the cases where we can avoid it. This 1884 * is when there is no cookie so we are doing a suspend & resume 1885 * (i.e. called from zil_vdev_offline()), and there's nothing to do 1886 * for the suspend because it's already suspended, or there's no ZIL. 1887 */ 1888 if (cookiep == NULL && !zilog->zl_suspending && 1889 (zilog->zl_suspend > 0 || BP_IS_HOLE(&zh->zh_log))) { 1890 mutex_exit(&zilog->zl_lock); 1891 dmu_objset_rele(os, suspend_tag); 1892 return (0); 1893 } 1894 1895 dsl_dataset_long_hold(dmu_objset_ds(os), suspend_tag); 1896 dsl_pool_rele(dmu_objset_pool(os), suspend_tag); 1897 1898 zilog->zl_suspend++; 1899 1900 if (zilog->zl_suspend > 1) { 1901 /* 1902 * Someone else is already suspending it. 1903 * Just wait for them to finish. 1904 */ 1905 1906 while (zilog->zl_suspending) 1907 cv_wait(&zilog->zl_cv_suspend, &zilog->zl_lock); 1908 mutex_exit(&zilog->zl_lock); 1909 1910 if (cookiep == NULL) 1911 zil_resume(os); 1912 else 1913 *cookiep = os; 1914 return (0); 1915 } 1916 1917 /* 1918 * If there is no pointer to an on-disk block, this ZIL must not 1919 * be active (e.g. filesystem not mounted), so there's nothing 1920 * to clean up. 1921 */ 1922 if (BP_IS_HOLE(&zh->zh_log)) { 1923 ASSERT(cookiep != NULL); /* fast path already handled */ 1924 1925 *cookiep = os; 1926 mutex_exit(&zilog->zl_lock); 1927 return (0); 1928 } 1929 1930 zilog->zl_suspending = B_TRUE; 1931 mutex_exit(&zilog->zl_lock); 1932 1933 zil_commit(zilog, 0); 1934 1935 zil_destroy(zilog, B_FALSE); 1936 1937 mutex_enter(&zilog->zl_lock); 1938 zilog->zl_suspending = B_FALSE; 1939 cv_broadcast(&zilog->zl_cv_suspend); 1940 mutex_exit(&zilog->zl_lock); 1941 1942 if (cookiep == NULL) 1943 zil_resume(os); 1944 else 1945 *cookiep = os; 1946 return (0); 1947} 1948 1949void 1950zil_resume(void *cookie) 1951{ 1952 objset_t *os = cookie; 1953 zilog_t *zilog = dmu_objset_zil(os); 1954 1955 mutex_enter(&zilog->zl_lock); 1956 ASSERT(zilog->zl_suspend != 0); 1957 zilog->zl_suspend--; 1958 mutex_exit(&zilog->zl_lock); 1959 dsl_dataset_long_rele(dmu_objset_ds(os), suspend_tag); 1960 dsl_dataset_rele(dmu_objset_ds(os), suspend_tag); 1961} 1962 1963typedef struct zil_replay_arg { 1964 zil_replay_func_t **zr_replay; 1965 void *zr_arg; 1966 boolean_t zr_byteswap; 1967 char *zr_lr; 1968} zil_replay_arg_t; 1969 1970static int 1971zil_replay_error(zilog_t *zilog, lr_t *lr, int error) 1972{ 1973 char name[ZFS_MAX_DATASET_NAME_LEN]; 1974 1975 zilog->zl_replaying_seq--; /* didn't actually replay this one */ 1976 1977 dmu_objset_name(zilog->zl_os, name); 1978 1979 cmn_err(CE_WARN, "ZFS replay transaction error %d, " 1980 "dataset %s, seq 0x%llx, txtype %llu %s\n", error, name, 1981 (u_longlong_t)lr->lrc_seq, 1982 (u_longlong_t)(lr->lrc_txtype & ~TX_CI), 1983 (lr->lrc_txtype & TX_CI) ? "CI" : ""); 1984 1985 return (error); 1986} 1987 1988static int 1989zil_replay_log_record(zilog_t *zilog, lr_t *lr, void *zra, uint64_t claim_txg) 1990{ 1991 zil_replay_arg_t *zr = zra; 1992 const zil_header_t *zh = zilog->zl_header; 1993 uint64_t reclen = lr->lrc_reclen; 1994 uint64_t txtype = lr->lrc_txtype; 1995 int error = 0; 1996 1997 zilog->zl_replaying_seq = lr->lrc_seq; 1998 1999 if (lr->lrc_seq <= zh->zh_replay_seq) /* already replayed */ 2000 return (0); 2001 2002 if (lr->lrc_txg < claim_txg) /* already committed */ 2003 return (0); 2004 2005 /* Strip case-insensitive bit, still present in log record */ 2006 txtype &= ~TX_CI; 2007 2008 if (txtype == 0 || txtype >= TX_MAX_TYPE) 2009 return (zil_replay_error(zilog, lr, EINVAL)); 2010 2011 /* 2012 * If this record type can be logged out of order, the object 2013 * (lr_foid) may no longer exist. That's legitimate, not an error. 2014 */ 2015 if (TX_OOO(txtype)) { 2016 error = dmu_object_info(zilog->zl_os, 2017 ((lr_ooo_t *)lr)->lr_foid, NULL); 2018 if (error == ENOENT || error == EEXIST) 2019 return (0); 2020 } 2021 2022 /* 2023 * Make a copy of the data so we can revise and extend it. 2024 */ 2025 bcopy(lr, zr->zr_lr, reclen); 2026 2027 /* 2028 * If this is a TX_WRITE with a blkptr, suck in the data. 2029 */ 2030 if (txtype == TX_WRITE && reclen == sizeof (lr_write_t)) { 2031 error = zil_read_log_data(zilog, (lr_write_t *)lr, 2032 zr->zr_lr + reclen); 2033 if (error != 0) 2034 return (zil_replay_error(zilog, lr, error)); 2035 } 2036 2037 /* 2038 * The log block containing this lr may have been byteswapped 2039 * so that we can easily examine common fields like lrc_txtype. 2040 * However, the log is a mix of different record types, and only the 2041 * replay vectors know how to byteswap their records. Therefore, if 2042 * the lr was byteswapped, undo it before invoking the replay vector. 2043 */ 2044 if (zr->zr_byteswap) 2045 byteswap_uint64_array(zr->zr_lr, reclen); 2046 2047 /* 2048 * We must now do two things atomically: replay this log record, 2049 * and update the log header sequence number to reflect the fact that 2050 * we did so. At the end of each replay function the sequence number 2051 * is updated if we are in replay mode. 2052 */ 2053 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, zr->zr_byteswap); 2054 if (error != 0) { 2055 /* 2056 * The DMU's dnode layer doesn't see removes until the txg 2057 * commits, so a subsequent claim can spuriously fail with 2058 * EEXIST. So if we receive any error we try syncing out 2059 * any removes then retry the transaction. Note that we 2060 * specify B_FALSE for byteswap now, so we don't do it twice. 2061 */ 2062 txg_wait_synced(spa_get_dsl(zilog->zl_spa), 0); 2063 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, B_FALSE); 2064 if (error != 0) 2065 return (zil_replay_error(zilog, lr, error)); 2066 } 2067 return (0); 2068} 2069 2070/* ARGSUSED */ 2071static int 2072zil_incr_blks(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 2073{ 2074 zilog->zl_replay_blks++; 2075 2076 return (0); 2077} 2078 2079/* 2080 * If this dataset has a non-empty intent log, replay it and destroy it. 2081 */ 2082void 2083zil_replay(objset_t *os, void *arg, zil_replay_func_t *replay_func[TX_MAX_TYPE]) 2084{ 2085 zilog_t *zilog = dmu_objset_zil(os); 2086 const zil_header_t *zh = zilog->zl_header; 2087 zil_replay_arg_t zr; 2088 2089 if ((zh->zh_flags & ZIL_REPLAY_NEEDED) == 0) { 2090 zil_destroy(zilog, B_TRUE); 2091 return; 2092 } 2093 2094 zr.zr_replay = replay_func; 2095 zr.zr_arg = arg; 2096 zr.zr_byteswap = BP_SHOULD_BYTESWAP(&zh->zh_log); 2097 zr.zr_lr = kmem_alloc(2 * SPA_MAXBLOCKSIZE, KM_SLEEP); 2098 2099 /* 2100 * Wait for in-progress removes to sync before starting replay. 2101 */ 2102 txg_wait_synced(zilog->zl_dmu_pool, 0); 2103 2104 zilog->zl_replay = B_TRUE; 2105 zilog->zl_replay_time = ddi_get_lbolt(); 2106 ASSERT(zilog->zl_replay_blks == 0); 2107 (void) zil_parse(zilog, zil_incr_blks, zil_replay_log_record, &zr, 2108 zh->zh_claim_txg); 2109 kmem_free(zr.zr_lr, 2 * SPA_MAXBLOCKSIZE); 2110 2111 zil_destroy(zilog, B_FALSE); 2112 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 2113 zilog->zl_replay = B_FALSE; 2114} 2115 2116boolean_t 2117zil_replaying(zilog_t *zilog, dmu_tx_t *tx) 2118{ 2119 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 2120 return (B_TRUE); 2121 2122 if (zilog->zl_replay) { 2123 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 2124 zilog->zl_replayed_seq[dmu_tx_get_txg(tx) & TXG_MASK] = 2125 zilog->zl_replaying_seq; 2126 return (B_TRUE); 2127 } 2128 2129 return (B_FALSE); 2130} 2131 2132/* ARGSUSED */ 2133int 2134zil_vdev_offline(const char *osname, void *arg) 2135{ 2136 int error; 2137 2138 error = zil_suspend(osname, NULL); 2139 if (error != 0) 2140 return (SET_ERROR(EEXIST)); 2141 return (0); 2142} 2143