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, 2016 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); 74TUNABLE_INT("vfs.zfs.zil_replay_disable", &zil_replay_disable); 75SYSCTL_INT(_vfs_zfs, OID_AUTO, zil_replay_disable, CTLFLAG_RW, 76 &zil_replay_disable, 0, "Disable intent logging replay"); 77 78/* 79 * Tunable parameter for debugging or performance analysis. Setting 80 * zfs_nocacheflush will cause corruption on power loss if a volatile 81 * out-of-order write cache is enabled. 82 */ 83boolean_t zfs_nocacheflush = B_FALSE; 84TUNABLE_INT("vfs.zfs.cache_flush_disable", &zfs_nocacheflush); 85SYSCTL_INT(_vfs_zfs, OID_AUTO, cache_flush_disable, CTLFLAG_RDTUN, 86 &zfs_nocacheflush, 0, "Disable cache flush"); 87boolean_t zfs_trim_enabled = B_TRUE; 88SYSCTL_DECL(_vfs_zfs_trim); 89TUNABLE_INT("vfs.zfs.trim.enabled", &zfs_trim_enabled); 90SYSCTL_INT(_vfs_zfs_trim, OID_AUTO, enabled, CTLFLAG_RDTUN, &zfs_trim_enabled, 0, 91 "Enable ZFS TRIM"); 92 93/* 94 * Limit SLOG write size per commit executed with synchronous priority. 95 * Any writes above that executed with lower (asynchronous) priority to 96 * limit potential SLOG device abuse by single active ZIL writer. 97 */ 98uint64_t zil_slog_limit = 768 * 1024; 99SYSCTL_QUAD(_vfs_zfs, OID_AUTO, zil_slog_limit, CTLFLAG_RWTUN, 100 &zil_slog_limit, 0, "Maximal SLOG commit size with sync priority"); 101 102static kmem_cache_t *zil_lwb_cache; 103 104#define LWB_EMPTY(lwb) ((BP_GET_LSIZE(&lwb->lwb_blk) - \ 105 sizeof (zil_chain_t)) == (lwb->lwb_sz - lwb->lwb_nused)) 106 107 108/* 109 * ziltest is by and large an ugly hack, but very useful in 110 * checking replay without tedious work. 111 * When running ziltest we want to keep all itx's and so maintain 112 * a single list in the zl_itxg[] that uses a high txg: ZILTEST_TXG 113 * We subtract TXG_CONCURRENT_STATES to allow for common code. 114 */ 115#define ZILTEST_TXG (UINT64_MAX - TXG_CONCURRENT_STATES) 116 117static int 118zil_bp_compare(const void *x1, const void *x2) 119{ 120 const dva_t *dva1 = &((zil_bp_node_t *)x1)->zn_dva; 121 const dva_t *dva2 = &((zil_bp_node_t *)x2)->zn_dva; 122 123 if (DVA_GET_VDEV(dva1) < DVA_GET_VDEV(dva2)) 124 return (-1); 125 if (DVA_GET_VDEV(dva1) > DVA_GET_VDEV(dva2)) 126 return (1); 127 128 if (DVA_GET_OFFSET(dva1) < DVA_GET_OFFSET(dva2)) 129 return (-1); 130 if (DVA_GET_OFFSET(dva1) > DVA_GET_OFFSET(dva2)) 131 return (1); 132 133 return (0); 134} 135 136static void 137zil_bp_tree_init(zilog_t *zilog) 138{ 139 avl_create(&zilog->zl_bp_tree, zil_bp_compare, 140 sizeof (zil_bp_node_t), offsetof(zil_bp_node_t, zn_node)); 141} 142 143static void 144zil_bp_tree_fini(zilog_t *zilog) 145{ 146 avl_tree_t *t = &zilog->zl_bp_tree; 147 zil_bp_node_t *zn; 148 void *cookie = NULL; 149 150 while ((zn = avl_destroy_nodes(t, &cookie)) != NULL) 151 kmem_free(zn, sizeof (zil_bp_node_t)); 152 153 avl_destroy(t); 154} 155 156int 157zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp) 158{ 159 avl_tree_t *t = &zilog->zl_bp_tree; 160 const dva_t *dva; 161 zil_bp_node_t *zn; 162 avl_index_t where; 163 164 if (BP_IS_EMBEDDED(bp)) 165 return (0); 166 167 dva = BP_IDENTITY(bp); 168 169 if (avl_find(t, dva, &where) != NULL) 170 return (SET_ERROR(EEXIST)); 171 172 zn = kmem_alloc(sizeof (zil_bp_node_t), KM_SLEEP); 173 zn->zn_dva = *dva; 174 avl_insert(t, zn, where); 175 176 return (0); 177} 178 179static zil_header_t * 180zil_header_in_syncing_context(zilog_t *zilog) 181{ 182 return ((zil_header_t *)zilog->zl_header); 183} 184 185static void 186zil_init_log_chain(zilog_t *zilog, blkptr_t *bp) 187{ 188 zio_cksum_t *zc = &bp->blk_cksum; 189 190 zc->zc_word[ZIL_ZC_GUID_0] = spa_get_random(-1ULL); 191 zc->zc_word[ZIL_ZC_GUID_1] = spa_get_random(-1ULL); 192 zc->zc_word[ZIL_ZC_OBJSET] = dmu_objset_id(zilog->zl_os); 193 zc->zc_word[ZIL_ZC_SEQ] = 1ULL; 194} 195 196/* 197 * Read a log block and make sure it's valid. 198 */ 199static int 200zil_read_log_block(zilog_t *zilog, const blkptr_t *bp, blkptr_t *nbp, void *dst, 201 char **end) 202{ 203 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 204 arc_flags_t aflags = ARC_FLAG_WAIT; 205 arc_buf_t *abuf = NULL; 206 zbookmark_phys_t zb; 207 int error; 208 209 if (zilog->zl_header->zh_claim_txg == 0) 210 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 211 212 if (!(zilog->zl_header->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 213 zio_flags |= ZIO_FLAG_SPECULATIVE; 214 215 SET_BOOKMARK(&zb, bp->blk_cksum.zc_word[ZIL_ZC_OBJSET], 216 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); 217 218 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 219 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 220 221 if (error == 0) { 222 zio_cksum_t cksum = bp->blk_cksum; 223 224 /* 225 * Validate the checksummed log block. 226 * 227 * Sequence numbers should be... sequential. The checksum 228 * verifier for the next block should be bp's checksum plus 1. 229 * 230 * Also check the log chain linkage and size used. 231 */ 232 cksum.zc_word[ZIL_ZC_SEQ]++; 233 234 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 235 zil_chain_t *zilc = abuf->b_data; 236 char *lr = (char *)(zilc + 1); 237 uint64_t len = zilc->zc_nused - sizeof (zil_chain_t); 238 239 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 240 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk)) { 241 error = SET_ERROR(ECKSUM); 242 } else { 243 ASSERT3U(len, <=, SPA_OLD_MAXBLOCKSIZE); 244 bcopy(lr, dst, len); 245 *end = (char *)dst + len; 246 *nbp = zilc->zc_next_blk; 247 } 248 } else { 249 char *lr = abuf->b_data; 250 uint64_t size = BP_GET_LSIZE(bp); 251 zil_chain_t *zilc = (zil_chain_t *)(lr + size) - 1; 252 253 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 254 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk) || 255 (zilc->zc_nused > (size - sizeof (*zilc)))) { 256 error = SET_ERROR(ECKSUM); 257 } else { 258 ASSERT3U(zilc->zc_nused, <=, 259 SPA_OLD_MAXBLOCKSIZE); 260 bcopy(lr, dst, zilc->zc_nused); 261 *end = (char *)dst + zilc->zc_nused; 262 *nbp = zilc->zc_next_blk; 263 } 264 } 265 266 arc_buf_destroy(abuf, &abuf); 267 } 268 269 return (error); 270} 271 272/* 273 * Read a TX_WRITE log data block. 274 */ 275static int 276zil_read_log_data(zilog_t *zilog, const lr_write_t *lr, void *wbuf) 277{ 278 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 279 const blkptr_t *bp = &lr->lr_blkptr; 280 arc_flags_t aflags = ARC_FLAG_WAIT; 281 arc_buf_t *abuf = NULL; 282 zbookmark_phys_t zb; 283 int error; 284 285 if (BP_IS_HOLE(bp)) { 286 if (wbuf != NULL) 287 bzero(wbuf, MAX(BP_GET_LSIZE(bp), lr->lr_length)); 288 return (0); 289 } 290 291 if (zilog->zl_header->zh_claim_txg == 0) 292 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 293 294 SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os), lr->lr_foid, 295 ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp)); 296 297 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 298 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 299 300 if (error == 0) { 301 if (wbuf != NULL) 302 bcopy(abuf->b_data, wbuf, arc_buf_size(abuf)); 303 arc_buf_destroy(abuf, &abuf); 304 } 305 306 return (error); 307} 308 309/* 310 * Parse the intent log, and call parse_func for each valid record within. 311 */ 312int 313zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func, 314 zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg) 315{ 316 const zil_header_t *zh = zilog->zl_header; 317 boolean_t claimed = !!zh->zh_claim_txg; 318 uint64_t claim_blk_seq = claimed ? zh->zh_claim_blk_seq : UINT64_MAX; 319 uint64_t claim_lr_seq = claimed ? zh->zh_claim_lr_seq : UINT64_MAX; 320 uint64_t max_blk_seq = 0; 321 uint64_t max_lr_seq = 0; 322 uint64_t blk_count = 0; 323 uint64_t lr_count = 0; 324 blkptr_t blk, next_blk; 325 char *lrbuf, *lrp; 326 int error = 0; 327 328 /* 329 * Old logs didn't record the maximum zh_claim_lr_seq. 330 */ 331 if (!(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 332 claim_lr_seq = UINT64_MAX; 333 334 /* 335 * Starting at the block pointed to by zh_log we read the log chain. 336 * For each block in the chain we strongly check that block to 337 * ensure its validity. We stop when an invalid block is found. 338 * For each block pointer in the chain we call parse_blk_func(). 339 * For each record in each valid block we call parse_lr_func(). 340 * If the log has been claimed, stop if we encounter a sequence 341 * number greater than the highest claimed sequence number. 342 */ 343 lrbuf = zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE); 344 zil_bp_tree_init(zilog); 345 346 for (blk = zh->zh_log; !BP_IS_HOLE(&blk); blk = next_blk) { 347 uint64_t blk_seq = blk.blk_cksum.zc_word[ZIL_ZC_SEQ]; 348 int reclen; 349 char *end; 350 351 if (blk_seq > claim_blk_seq) 352 break; 353 if ((error = parse_blk_func(zilog, &blk, arg, txg)) != 0) 354 break; 355 ASSERT3U(max_blk_seq, <, blk_seq); 356 max_blk_seq = blk_seq; 357 blk_count++; 358 359 if (max_lr_seq == claim_lr_seq && max_blk_seq == claim_blk_seq) 360 break; 361 362 error = zil_read_log_block(zilog, &blk, &next_blk, lrbuf, &end); 363 if (error != 0) 364 break; 365 366 for (lrp = lrbuf; lrp < end; lrp += reclen) { 367 lr_t *lr = (lr_t *)lrp; 368 reclen = lr->lrc_reclen; 369 ASSERT3U(reclen, >=, sizeof (lr_t)); 370 if (lr->lrc_seq > claim_lr_seq) 371 goto done; 372 if ((error = parse_lr_func(zilog, lr, arg, txg)) != 0) 373 goto done; 374 ASSERT3U(max_lr_seq, <, lr->lrc_seq); 375 max_lr_seq = lr->lrc_seq; 376 lr_count++; 377 } 378 } 379done: 380 zilog->zl_parse_error = error; 381 zilog->zl_parse_blk_seq = max_blk_seq; 382 zilog->zl_parse_lr_seq = max_lr_seq; 383 zilog->zl_parse_blk_count = blk_count; 384 zilog->zl_parse_lr_count = lr_count; 385 386 ASSERT(!claimed || !(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID) || 387 (max_blk_seq == claim_blk_seq && max_lr_seq == claim_lr_seq)); 388 389 zil_bp_tree_fini(zilog); 390 zio_buf_free(lrbuf, SPA_OLD_MAXBLOCKSIZE); 391 392 return (error); 393} 394 395static int 396zil_claim_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t first_txg) 397{ 398 /* 399 * Claim log block if not already committed and not already claimed. 400 * If tx == NULL, just verify that the block is claimable. 401 */ 402 if (BP_IS_HOLE(bp) || bp->blk_birth < first_txg || 403 zil_bp_tree_add(zilog, bp) != 0) 404 return (0); 405 406 return (zio_wait(zio_claim(NULL, zilog->zl_spa, 407 tx == NULL ? 0 : first_txg, bp, spa_claim_notify, NULL, 408 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB))); 409} 410 411static int 412zil_claim_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t first_txg) 413{ 414 lr_write_t *lr = (lr_write_t *)lrc; 415 int error; 416 417 if (lrc->lrc_txtype != TX_WRITE) 418 return (0); 419 420 /* 421 * If the block is not readable, don't claim it. This can happen 422 * in normal operation when a log block is written to disk before 423 * some of the dmu_sync() blocks it points to. In this case, the 424 * transaction cannot have been committed to anyone (we would have 425 * waited for all writes to be stable first), so it is semantically 426 * correct to declare this the end of the log. 427 */ 428 if (lr->lr_blkptr.blk_birth >= first_txg && 429 (error = zil_read_log_data(zilog, lr, NULL)) != 0) 430 return (error); 431 return (zil_claim_log_block(zilog, &lr->lr_blkptr, tx, first_txg)); 432} 433 434/* ARGSUSED */ 435static int 436zil_free_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t claim_txg) 437{ 438 zio_free_zil(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 439 440 return (0); 441} 442 443static int 444zil_free_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t claim_txg) 445{ 446 lr_write_t *lr = (lr_write_t *)lrc; 447 blkptr_t *bp = &lr->lr_blkptr; 448 449 /* 450 * If we previously claimed it, we need to free it. 451 */ 452 if (claim_txg != 0 && lrc->lrc_txtype == TX_WRITE && 453 bp->blk_birth >= claim_txg && zil_bp_tree_add(zilog, bp) == 0 && 454 !BP_IS_HOLE(bp)) 455 zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 456 457 return (0); 458} 459 460static lwb_t * 461zil_alloc_lwb(zilog_t *zilog, blkptr_t *bp, boolean_t slog, uint64_t txg) 462{ 463 lwb_t *lwb; 464 465 lwb = kmem_cache_alloc(zil_lwb_cache, KM_SLEEP); 466 lwb->lwb_zilog = zilog; 467 lwb->lwb_blk = *bp; 468 lwb->lwb_slog = slog; 469 lwb->lwb_buf = zio_buf_alloc(BP_GET_LSIZE(bp)); 470 lwb->lwb_max_txg = txg; 471 lwb->lwb_zio = NULL; 472 lwb->lwb_tx = NULL; 473 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 474 lwb->lwb_nused = sizeof (zil_chain_t); 475 lwb->lwb_sz = BP_GET_LSIZE(bp); 476 } else { 477 lwb->lwb_nused = 0; 478 lwb->lwb_sz = BP_GET_LSIZE(bp) - sizeof (zil_chain_t); 479 } 480 481 mutex_enter(&zilog->zl_lock); 482 list_insert_tail(&zilog->zl_lwb_list, lwb); 483 mutex_exit(&zilog->zl_lock); 484 485 return (lwb); 486} 487 488/* 489 * Called when we create in-memory log transactions so that we know 490 * to cleanup the itxs at the end of spa_sync(). 491 */ 492void 493zilog_dirty(zilog_t *zilog, uint64_t txg) 494{ 495 dsl_pool_t *dp = zilog->zl_dmu_pool; 496 dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); 497 498 if (ds->ds_is_snapshot) 499 panic("dirtying snapshot!"); 500 501 if (txg_list_add(&dp->dp_dirty_zilogs, zilog, txg)) { 502 /* up the hold count until we can be written out */ 503 dmu_buf_add_ref(ds->ds_dbuf, zilog); 504 } 505} 506 507/* 508 * Determine if the zil is dirty in the specified txg. Callers wanting to 509 * ensure that the dirty state does not change must hold the itxg_lock for 510 * the specified txg. Holding the lock will ensure that the zil cannot be 511 * dirtied (zil_itx_assign) or cleaned (zil_clean) while we check its current 512 * state. 513 */ 514boolean_t 515zilog_is_dirty_in_txg(zilog_t *zilog, uint64_t txg) 516{ 517 dsl_pool_t *dp = zilog->zl_dmu_pool; 518 519 if (txg_list_member(&dp->dp_dirty_zilogs, zilog, txg & TXG_MASK)) 520 return (B_TRUE); 521 return (B_FALSE); 522} 523 524/* 525 * Determine if the zil is dirty. The zil is considered dirty if it has 526 * any pending itx records that have not been cleaned by zil_clean(). 527 */ 528boolean_t 529zilog_is_dirty(zilog_t *zilog) 530{ 531 dsl_pool_t *dp = zilog->zl_dmu_pool; 532 533 for (int t = 0; t < TXG_SIZE; t++) { 534 if (txg_list_member(&dp->dp_dirty_zilogs, zilog, t)) 535 return (B_TRUE); 536 } 537 return (B_FALSE); 538} 539 540/* 541 * Create an on-disk intent log. 542 */ 543static lwb_t * 544zil_create(zilog_t *zilog) 545{ 546 const zil_header_t *zh = zilog->zl_header; 547 lwb_t *lwb = NULL; 548 uint64_t txg = 0; 549 dmu_tx_t *tx = NULL; 550 blkptr_t blk; 551 int error = 0; 552 boolean_t slog = FALSE; 553 554 /* 555 * Wait for any previous destroy to complete. 556 */ 557 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 558 559 ASSERT(zh->zh_claim_txg == 0); 560 ASSERT(zh->zh_replay_seq == 0); 561 562 blk = zh->zh_log; 563 564 /* 565 * Allocate an initial log block if: 566 * - there isn't one already 567 * - the existing block is the wrong endianess 568 */ 569 if (BP_IS_HOLE(&blk) || BP_SHOULD_BYTESWAP(&blk)) { 570 tx = dmu_tx_create(zilog->zl_os); 571 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 572 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 573 txg = dmu_tx_get_txg(tx); 574 575 if (!BP_IS_HOLE(&blk)) { 576 zio_free_zil(zilog->zl_spa, txg, &blk); 577 BP_ZERO(&blk); 578 } 579 580 error = zio_alloc_zil(zilog->zl_spa, txg, &blk, NULL, 581 ZIL_MIN_BLKSZ, &slog); 582 583 if (error == 0) 584 zil_init_log_chain(zilog, &blk); 585 } 586 587 /* 588 * Allocate a log write buffer (lwb) for the first log block. 589 */ 590 if (error == 0) 591 lwb = zil_alloc_lwb(zilog, &blk, slog, txg); 592 593 /* 594 * If we just allocated the first log block, commit our transaction 595 * and wait for zil_sync() to stuff the block poiner into zh_log. 596 * (zh is part of the MOS, so we cannot modify it in open context.) 597 */ 598 if (tx != NULL) { 599 dmu_tx_commit(tx); 600 txg_wait_synced(zilog->zl_dmu_pool, txg); 601 } 602 603 ASSERT(bcmp(&blk, &zh->zh_log, sizeof (blk)) == 0); 604 605 return (lwb); 606} 607 608/* 609 * In one tx, free all log blocks and clear the log header. 610 * If keep_first is set, then we're replaying a log with no content. 611 * We want to keep the first block, however, so that the first 612 * synchronous transaction doesn't require a txg_wait_synced() 613 * in zil_create(). We don't need to txg_wait_synced() here either 614 * when keep_first is set, because both zil_create() and zil_destroy() 615 * will wait for any in-progress destroys to complete. 616 */ 617void 618zil_destroy(zilog_t *zilog, boolean_t keep_first) 619{ 620 const zil_header_t *zh = zilog->zl_header; 621 lwb_t *lwb; 622 dmu_tx_t *tx; 623 uint64_t txg; 624 625 /* 626 * Wait for any previous destroy to complete. 627 */ 628 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 629 630 zilog->zl_old_header = *zh; /* debugging aid */ 631 632 if (BP_IS_HOLE(&zh->zh_log)) 633 return; 634 635 tx = dmu_tx_create(zilog->zl_os); 636 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 637 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 638 txg = dmu_tx_get_txg(tx); 639 640 mutex_enter(&zilog->zl_lock); 641 642 ASSERT3U(zilog->zl_destroy_txg, <, txg); 643 zilog->zl_destroy_txg = txg; 644 zilog->zl_keep_first = keep_first; 645 646 if (!list_is_empty(&zilog->zl_lwb_list)) { 647 ASSERT(zh->zh_claim_txg == 0); 648 VERIFY(!keep_first); 649 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 650 list_remove(&zilog->zl_lwb_list, lwb); 651 if (lwb->lwb_buf != NULL) 652 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 653 zio_free_zil(zilog->zl_spa, txg, &lwb->lwb_blk); 654 kmem_cache_free(zil_lwb_cache, lwb); 655 } 656 } else if (!keep_first) { 657 zil_destroy_sync(zilog, tx); 658 } 659 mutex_exit(&zilog->zl_lock); 660 661 dmu_tx_commit(tx); 662} 663 664void 665zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx) 666{ 667 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 668 (void) zil_parse(zilog, zil_free_log_block, 669 zil_free_log_record, tx, zilog->zl_header->zh_claim_txg); 670} 671 672int 673zil_claim(dsl_pool_t *dp, dsl_dataset_t *ds, void *txarg) 674{ 675 dmu_tx_t *tx = txarg; 676 uint64_t first_txg = dmu_tx_get_txg(tx); 677 zilog_t *zilog; 678 zil_header_t *zh; 679 objset_t *os; 680 int error; 681 682 error = dmu_objset_own_obj(dp, ds->ds_object, 683 DMU_OST_ANY, B_FALSE, FTAG, &os); 684 if (error != 0) { 685 /* 686 * EBUSY indicates that the objset is inconsistent, in which 687 * case it can not have a ZIL. 688 */ 689 if (error != EBUSY) { 690 cmn_err(CE_WARN, "can't open objset for %llu, error %u", 691 (unsigned long long)ds->ds_object, error); 692 } 693 return (0); 694 } 695 696 zilog = dmu_objset_zil(os); 697 zh = zil_header_in_syncing_context(zilog); 698 699 if (spa_get_log_state(zilog->zl_spa) == SPA_LOG_CLEAR) { 700 if (!BP_IS_HOLE(&zh->zh_log)) 701 zio_free_zil(zilog->zl_spa, first_txg, &zh->zh_log); 702 BP_ZERO(&zh->zh_log); 703 dsl_dataset_dirty(dmu_objset_ds(os), tx); 704 dmu_objset_disown(os, FTAG); 705 return (0); 706 } 707 708 /* 709 * Claim all log blocks if we haven't already done so, and remember 710 * the highest claimed sequence number. This ensures that if we can 711 * read only part of the log now (e.g. due to a missing device), 712 * but we can read the entire log later, we will not try to replay 713 * or destroy beyond the last block we successfully claimed. 714 */ 715 ASSERT3U(zh->zh_claim_txg, <=, first_txg); 716 if (zh->zh_claim_txg == 0 && !BP_IS_HOLE(&zh->zh_log)) { 717 (void) zil_parse(zilog, zil_claim_log_block, 718 zil_claim_log_record, tx, first_txg); 719 zh->zh_claim_txg = first_txg; 720 zh->zh_claim_blk_seq = zilog->zl_parse_blk_seq; 721 zh->zh_claim_lr_seq = zilog->zl_parse_lr_seq; 722 if (zilog->zl_parse_lr_count || zilog->zl_parse_blk_count > 1) 723 zh->zh_flags |= ZIL_REPLAY_NEEDED; 724 zh->zh_flags |= ZIL_CLAIM_LR_SEQ_VALID; 725 dsl_dataset_dirty(dmu_objset_ds(os), tx); 726 } 727 728 ASSERT3U(first_txg, ==, (spa_last_synced_txg(zilog->zl_spa) + 1)); 729 dmu_objset_disown(os, FTAG); 730 return (0); 731} 732 733/* 734 * Check the log by walking the log chain. 735 * Checksum errors are ok as they indicate the end of the chain. 736 * Any other error (no device or read failure) returns an error. 737 */ 738/* ARGSUSED */ 739int 740zil_check_log_chain(dsl_pool_t *dp, dsl_dataset_t *ds, void *tx) 741{ 742 zilog_t *zilog; 743 objset_t *os; 744 blkptr_t *bp; 745 int error; 746 747 ASSERT(tx == NULL); 748 749 error = dmu_objset_from_ds(ds, &os); 750 if (error != 0) { 751 cmn_err(CE_WARN, "can't open objset %llu, error %d", 752 (unsigned long long)ds->ds_object, error); 753 return (0); 754 } 755 756 zilog = dmu_objset_zil(os); 757 bp = (blkptr_t *)&zilog->zl_header->zh_log; 758 759 /* 760 * Check the first block and determine if it's on a log device 761 * which may have been removed or faulted prior to loading this 762 * pool. If so, there's no point in checking the rest of the log 763 * as its content should have already been synced to the pool. 764 */ 765 if (!BP_IS_HOLE(bp)) { 766 vdev_t *vd; 767 boolean_t valid = B_TRUE; 768 769 spa_config_enter(os->os_spa, SCL_STATE, FTAG, RW_READER); 770 vd = vdev_lookup_top(os->os_spa, DVA_GET_VDEV(&bp->blk_dva[0])); 771 if (vd->vdev_islog && vdev_is_dead(vd)) 772 valid = vdev_log_state_valid(vd); 773 spa_config_exit(os->os_spa, SCL_STATE, FTAG); 774 775 if (!valid) 776 return (0); 777 } 778 779 /* 780 * Because tx == NULL, zil_claim_log_block() will not actually claim 781 * any blocks, but just determine whether it is possible to do so. 782 * In addition to checking the log chain, zil_claim_log_block() 783 * will invoke zio_claim() with a done func of spa_claim_notify(), 784 * which will update spa_max_claim_txg. See spa_load() for details. 785 */ 786 error = zil_parse(zilog, zil_claim_log_block, zil_claim_log_record, tx, 787 zilog->zl_header->zh_claim_txg ? -1ULL : spa_first_txg(os->os_spa)); 788 789 return ((error == ECKSUM || error == ENOENT) ? 0 : error); 790} 791 792static int 793zil_vdev_compare(const void *x1, const void *x2) 794{ 795 const uint64_t v1 = ((zil_vdev_node_t *)x1)->zv_vdev; 796 const uint64_t v2 = ((zil_vdev_node_t *)x2)->zv_vdev; 797 798 if (v1 < v2) 799 return (-1); 800 if (v1 > v2) 801 return (1); 802 803 return (0); 804} 805 806void 807zil_add_block(zilog_t *zilog, const blkptr_t *bp) 808{ 809 avl_tree_t *t = &zilog->zl_vdev_tree; 810 avl_index_t where; 811 zil_vdev_node_t *zv, zvsearch; 812 int ndvas = BP_GET_NDVAS(bp); 813 int i; 814 815 if (zfs_nocacheflush) 816 return; 817 818 ASSERT(zilog->zl_writer); 819 820 /* 821 * Even though we're zl_writer, we still need a lock because the 822 * zl_get_data() callbacks may have dmu_sync() done callbacks 823 * that will run concurrently. 824 */ 825 mutex_enter(&zilog->zl_vdev_lock); 826 for (i = 0; i < ndvas; i++) { 827 zvsearch.zv_vdev = DVA_GET_VDEV(&bp->blk_dva[i]); 828 if (avl_find(t, &zvsearch, &where) == NULL) { 829 zv = kmem_alloc(sizeof (*zv), KM_SLEEP); 830 zv->zv_vdev = zvsearch.zv_vdev; 831 avl_insert(t, zv, where); 832 } 833 } 834 mutex_exit(&zilog->zl_vdev_lock); 835} 836 837static void 838zil_flush_vdevs(zilog_t *zilog) 839{ 840 spa_t *spa = zilog->zl_spa; 841 avl_tree_t *t = &zilog->zl_vdev_tree; 842 void *cookie = NULL; 843 zil_vdev_node_t *zv; 844 zio_t *zio = NULL; 845 846 ASSERT(zilog->zl_writer); 847 848 /* 849 * We don't need zl_vdev_lock here because we're the zl_writer, 850 * and all zl_get_data() callbacks are done. 851 */ 852 if (avl_numnodes(t) == 0) 853 return; 854 855 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 856 857 while ((zv = avl_destroy_nodes(t, &cookie)) != NULL) { 858 vdev_t *vd = vdev_lookup_top(spa, zv->zv_vdev); 859 if (vd != NULL && !vd->vdev_nowritecache) { 860 if (zio == NULL) 861 zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL); 862 zio_flush(zio, vd); 863 } 864 kmem_free(zv, sizeof (*zv)); 865 } 866 867 /* 868 * Wait for all the flushes to complete. Not all devices actually 869 * support the DKIOCFLUSHWRITECACHE ioctl, so it's OK if it fails. 870 */ 871 if (zio) 872 (void) zio_wait(zio); 873 874 spa_config_exit(spa, SCL_STATE, FTAG); 875} 876 877/* 878 * Function called when a log block write completes 879 */ 880static void 881zil_lwb_write_done(zio_t *zio) 882{ 883 lwb_t *lwb = zio->io_private; 884 zilog_t *zilog = lwb->lwb_zilog; 885 dmu_tx_t *tx = lwb->lwb_tx; 886 887 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); 888 ASSERT(BP_GET_TYPE(zio->io_bp) == DMU_OT_INTENT_LOG); 889 ASSERT(BP_GET_LEVEL(zio->io_bp) == 0); 890 ASSERT(BP_GET_BYTEORDER(zio->io_bp) == ZFS_HOST_BYTEORDER); 891 ASSERT(!BP_IS_GANG(zio->io_bp)); 892 ASSERT(!BP_IS_HOLE(zio->io_bp)); 893 ASSERT(BP_GET_FILL(zio->io_bp) == 0); 894 895 /* 896 * Ensure the lwb buffer pointer is cleared before releasing 897 * the txg. If we have had an allocation failure and 898 * the txg is waiting to sync then we want want zil_sync() 899 * to remove the lwb so that it's not picked up as the next new 900 * one in zil_commit_writer(). zil_sync() will only remove 901 * the lwb if lwb_buf is null. 902 */ 903 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 904 mutex_enter(&zilog->zl_lock); 905 lwb->lwb_buf = NULL; 906 lwb->lwb_tx = NULL; 907 mutex_exit(&zilog->zl_lock); 908 909 /* 910 * Now that we've written this log block, we have a stable pointer 911 * to the next block in the chain, so it's OK to let the txg in 912 * which we allocated the next block sync. 913 */ 914 dmu_tx_commit(tx); 915} 916 917/* 918 * Initialize the io for a log block. 919 */ 920static void 921zil_lwb_write_init(zilog_t *zilog, lwb_t *lwb) 922{ 923 zbookmark_phys_t zb; 924 zio_priority_t prio; 925 926 SET_BOOKMARK(&zb, lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_OBJSET], 927 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, 928 lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_SEQ]); 929 930 if (zilog->zl_root_zio == NULL) { 931 zilog->zl_root_zio = zio_root(zilog->zl_spa, NULL, NULL, 932 ZIO_FLAG_CANFAIL); 933 } 934 if (lwb->lwb_zio == NULL) { 935 if (zilog->zl_cur_used <= zil_slog_limit || !lwb->lwb_slog) 936 prio = ZIO_PRIORITY_SYNC_WRITE; 937 else 938 prio = ZIO_PRIORITY_ASYNC_WRITE; 939 lwb->lwb_zio = zio_rewrite(zilog->zl_root_zio, zilog->zl_spa, 940 0, &lwb->lwb_blk, lwb->lwb_buf, BP_GET_LSIZE(&lwb->lwb_blk), 941 zil_lwb_write_done, lwb, prio, 942 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE, &zb); 943 } 944} 945 946/* 947 * Define a limited set of intent log block sizes. 948 * 949 * These must be a multiple of 4KB. Note only the amount used (again 950 * aligned to 4KB) actually gets written. However, we can't always just 951 * allocate SPA_OLD_MAXBLOCKSIZE as the slog space could be exhausted. 952 */ 953uint64_t zil_block_buckets[] = { 954 4096, /* non TX_WRITE */ 955 8192+4096, /* data base */ 956 32*1024 + 4096, /* NFS writes */ 957 UINT64_MAX 958}; 959 960/* 961 * Start a log block write and advance to the next log block. 962 * Calls are serialized. 963 */ 964static lwb_t * 965zil_lwb_write_start(zilog_t *zilog, lwb_t *lwb, boolean_t last) 966{ 967 lwb_t *nlwb = NULL; 968 zil_chain_t *zilc; 969 spa_t *spa = zilog->zl_spa; 970 blkptr_t *bp; 971 dmu_tx_t *tx; 972 uint64_t txg; 973 uint64_t zil_blksz, wsz; 974 int i, error; 975 boolean_t slog; 976 977 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 978 zilc = (zil_chain_t *)lwb->lwb_buf; 979 bp = &zilc->zc_next_blk; 980 } else { 981 zilc = (zil_chain_t *)(lwb->lwb_buf + lwb->lwb_sz); 982 bp = &zilc->zc_next_blk; 983 } 984 985 ASSERT(lwb->lwb_nused <= lwb->lwb_sz); 986 987 /* 988 * Allocate the next block and save its address in this block 989 * before writing it in order to establish the log chain. 990 * Note that if the allocation of nlwb synced before we wrote 991 * the block that points at it (lwb), we'd leak it if we crashed. 992 * Therefore, we don't do dmu_tx_commit() until zil_lwb_write_done(). 993 * We dirty the dataset to ensure that zil_sync() will be called 994 * to clean up in the event of allocation failure or I/O failure. 995 */ 996 tx = dmu_tx_create(zilog->zl_os); 997 998 /* 999 * Since we are not going to create any new dirty data, and we 1000 * can even help with clearing the existing dirty data, we 1001 * should not be subject to the dirty data based delays. We 1002 * use TXG_NOTHROTTLE to bypass the delay mechanism. 1003 */ 1004 VERIFY0(dmu_tx_assign(tx, TXG_WAIT | TXG_NOTHROTTLE)); 1005 1006 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 1007 txg = dmu_tx_get_txg(tx); 1008 1009 lwb->lwb_tx = tx; 1010 1011 /* 1012 * Log blocks are pre-allocated. Here we select the size of the next 1013 * block, based on size used in the last block. 1014 * - first find the smallest bucket that will fit the block from a 1015 * limited set of block sizes. This is because it's faster to write 1016 * blocks allocated from the same metaslab as they are adjacent or 1017 * close. 1018 * - next find the maximum from the new suggested size and an array of 1019 * previous sizes. This lessens a picket fence effect of wrongly 1020 * guesssing the size if we have a stream of say 2k, 64k, 2k, 64k 1021 * requests. 1022 * 1023 * Note we only write what is used, but we can't just allocate 1024 * the maximum block size because we can exhaust the available 1025 * pool log space. 1026 */ 1027 zil_blksz = zilog->zl_cur_used + sizeof (zil_chain_t); 1028 for (i = 0; zil_blksz > zil_block_buckets[i]; i++) 1029 continue; 1030 zil_blksz = zil_block_buckets[i]; 1031 if (zil_blksz == UINT64_MAX) 1032 zil_blksz = SPA_OLD_MAXBLOCKSIZE; 1033 zilog->zl_prev_blks[zilog->zl_prev_rotor] = zil_blksz; 1034 for (i = 0; i < ZIL_PREV_BLKS; i++) 1035 zil_blksz = MAX(zil_blksz, zilog->zl_prev_blks[i]); 1036 zilog->zl_prev_rotor = (zilog->zl_prev_rotor + 1) & (ZIL_PREV_BLKS - 1); 1037 1038 BP_ZERO(bp); 1039 /* pass the old blkptr in order to spread log blocks across devs */ 1040 error = zio_alloc_zil(spa, txg, bp, &lwb->lwb_blk, zil_blksz, &slog); 1041 if (error == 0) { 1042 ASSERT3U(bp->blk_birth, ==, txg); 1043 bp->blk_cksum = lwb->lwb_blk.blk_cksum; 1044 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]++; 1045 1046 /* 1047 * Allocate a new log write buffer (lwb). 1048 */ 1049 nlwb = zil_alloc_lwb(zilog, bp, slog, txg); 1050 1051 /* Record the block for later vdev flushing */ 1052 zil_add_block(zilog, &lwb->lwb_blk); 1053 } 1054 1055 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 1056 /* For Slim ZIL only write what is used. */ 1057 wsz = P2ROUNDUP_TYPED(lwb->lwb_nused, ZIL_MIN_BLKSZ, uint64_t); 1058 ASSERT3U(wsz, <=, lwb->lwb_sz); 1059 zio_shrink(lwb->lwb_zio, wsz); 1060 1061 } else { 1062 wsz = lwb->lwb_sz; 1063 } 1064 1065 zilc->zc_pad = 0; 1066 zilc->zc_nused = lwb->lwb_nused; 1067 zilc->zc_eck.zec_cksum = lwb->lwb_blk.blk_cksum; 1068 1069 /* 1070 * clear unused data for security 1071 */ 1072 bzero(lwb->lwb_buf + lwb->lwb_nused, wsz - lwb->lwb_nused); 1073 1074 if (last) 1075 lwb->lwb_zio->io_pipeline &= ~ZIO_STAGE_ISSUE_ASYNC; 1076 zio_nowait(lwb->lwb_zio); /* Kick off the write for the old log block */ 1077 1078 /* 1079 * If there was an allocation failure then nlwb will be null which 1080 * forces a txg_wait_synced(). 1081 */ 1082 return (nlwb); 1083} 1084 1085static lwb_t * 1086zil_lwb_commit(zilog_t *zilog, itx_t *itx, lwb_t *lwb) 1087{ 1088 lr_t *lrcb, *lrc = &itx->itx_lr; /* common log record */ 1089 lr_write_t *lrwb, *lrw = (lr_write_t *)lrc; 1090 char *lr_buf; 1091 uint64_t txg = lrc->lrc_txg; 1092 uint64_t reclen = lrc->lrc_reclen; 1093 uint64_t dlen = 0; 1094 uint64_t dnow, lwb_sp; 1095 1096 if (lwb == NULL) 1097 return (NULL); 1098 1099 ASSERT(lwb->lwb_buf != NULL); 1100 1101 if (lrc->lrc_txtype == TX_WRITE && itx->itx_wr_state == WR_NEED_COPY) 1102 dlen = P2ROUNDUP_TYPED( 1103 lrw->lr_length, sizeof (uint64_t), uint64_t); 1104 1105 zilog->zl_cur_used += (reclen + dlen); 1106 1107 zil_lwb_write_init(zilog, lwb); 1108 1109cont: 1110 /* 1111 * If this record won't fit in the current log block, start a new one. 1112 * For WR_NEED_COPY optimize layout for minimal number of chunks, but 1113 * try to keep wasted space withing reasonable range (12%). 1114 */ 1115 lwb_sp = lwb->lwb_sz - lwb->lwb_nused; 1116 if (reclen > lwb_sp || (reclen + dlen > lwb_sp && 1117 lwb_sp < ZIL_MAX_LOG_DATA / 8 && (dlen % ZIL_MAX_LOG_DATA == 0 || 1118 lwb_sp < reclen + dlen % ZIL_MAX_LOG_DATA))) { 1119 lwb = zil_lwb_write_start(zilog, lwb, B_FALSE); 1120 if (lwb == NULL) 1121 return (NULL); 1122 zil_lwb_write_init(zilog, lwb); 1123 ASSERT(LWB_EMPTY(lwb)); 1124 lwb_sp = lwb->lwb_sz - lwb->lwb_nused; 1125 ASSERT3U(reclen + MIN(dlen, sizeof(uint64_t)), <=, lwb_sp); 1126 } 1127 1128 dnow = MIN(dlen, lwb_sp - reclen); 1129 lr_buf = lwb->lwb_buf + lwb->lwb_nused; 1130 bcopy(lrc, lr_buf, reclen); 1131 lrcb = (lr_t *)lr_buf; 1132 lrwb = (lr_write_t *)lrcb; 1133 1134 /* 1135 * If it's a write, fetch the data or get its blkptr as appropriate. 1136 */ 1137 if (lrc->lrc_txtype == TX_WRITE) { 1138 if (txg > spa_freeze_txg(zilog->zl_spa)) 1139 txg_wait_synced(zilog->zl_dmu_pool, txg); 1140 if (itx->itx_wr_state != WR_COPIED) { 1141 char *dbuf; 1142 int error; 1143 1144 if (itx->itx_wr_state == WR_NEED_COPY) { 1145 dbuf = lr_buf + reclen; 1146 lrcb->lrc_reclen += dnow; 1147 if (lrwb->lr_length > dnow) 1148 lrwb->lr_length = dnow; 1149 lrw->lr_offset += dnow; 1150 lrw->lr_length -= dnow; 1151 } else { 1152 ASSERT(itx->itx_wr_state == WR_INDIRECT); 1153 dbuf = NULL; 1154 } 1155 error = zilog->zl_get_data( 1156 itx->itx_private, lrwb, dbuf, lwb->lwb_zio); 1157 if (error == EIO) { 1158 txg_wait_synced(zilog->zl_dmu_pool, txg); 1159 return (lwb); 1160 } 1161 if (error != 0) { 1162 ASSERT(error == ENOENT || error == EEXIST || 1163 error == EALREADY); 1164 return (lwb); 1165 } 1166 } 1167 } 1168 1169 /* 1170 * We're actually making an entry, so update lrc_seq to be the 1171 * log record sequence number. Note that this is generally not 1172 * equal to the itx sequence number because not all transactions 1173 * are synchronous, and sometimes spa_sync() gets there first. 1174 */ 1175 lrcb->lrc_seq = ++zilog->zl_lr_seq; /* we are single threaded */ 1176 lwb->lwb_nused += reclen + dnow; 1177 lwb->lwb_max_txg = MAX(lwb->lwb_max_txg, txg); 1178 ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_sz); 1179 ASSERT0(P2PHASE(lwb->lwb_nused, sizeof (uint64_t))); 1180 1181 dlen -= dnow; 1182 if (dlen > 0) { 1183 zilog->zl_cur_used += reclen; 1184 goto cont; 1185 } 1186 1187 return (lwb); 1188} 1189 1190itx_t * 1191zil_itx_create(uint64_t txtype, size_t lrsize) 1192{ 1193 itx_t *itx; 1194 1195 lrsize = P2ROUNDUP_TYPED(lrsize, sizeof (uint64_t), size_t); 1196 1197 itx = kmem_alloc(offsetof(itx_t, itx_lr) + lrsize, KM_SLEEP); 1198 itx->itx_lr.lrc_txtype = txtype; 1199 itx->itx_lr.lrc_reclen = lrsize; 1200 itx->itx_lr.lrc_seq = 0; /* defensive */ 1201 itx->itx_sync = B_TRUE; /* default is synchronous */ 1202 1203 return (itx); 1204} 1205 1206void 1207zil_itx_destroy(itx_t *itx) 1208{ 1209 kmem_free(itx, offsetof(itx_t, itx_lr) + itx->itx_lr.lrc_reclen); 1210} 1211 1212/* 1213 * Free up the sync and async itxs. The itxs_t has already been detached 1214 * so no locks are needed. 1215 */ 1216static void 1217zil_itxg_clean(itxs_t *itxs) 1218{ 1219 itx_t *itx; 1220 list_t *list; 1221 avl_tree_t *t; 1222 void *cookie; 1223 itx_async_node_t *ian; 1224 1225 list = &itxs->i_sync_list; 1226 while ((itx = list_head(list)) != NULL) { 1227 list_remove(list, itx); 1228 kmem_free(itx, offsetof(itx_t, itx_lr) + 1229 itx->itx_lr.lrc_reclen); 1230 } 1231 1232 cookie = NULL; 1233 t = &itxs->i_async_tree; 1234 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1235 list = &ian->ia_list; 1236 while ((itx = list_head(list)) != NULL) { 1237 list_remove(list, itx); 1238 kmem_free(itx, offsetof(itx_t, itx_lr) + 1239 itx->itx_lr.lrc_reclen); 1240 } 1241 list_destroy(list); 1242 kmem_free(ian, sizeof (itx_async_node_t)); 1243 } 1244 avl_destroy(t); 1245 1246 kmem_free(itxs, sizeof (itxs_t)); 1247} 1248 1249static int 1250zil_aitx_compare(const void *x1, const void *x2) 1251{ 1252 const uint64_t o1 = ((itx_async_node_t *)x1)->ia_foid; 1253 const uint64_t o2 = ((itx_async_node_t *)x2)->ia_foid; 1254 1255 if (o1 < o2) 1256 return (-1); 1257 if (o1 > o2) 1258 return (1); 1259 1260 return (0); 1261} 1262 1263/* 1264 * Remove all async itx with the given oid. 1265 */ 1266static void 1267zil_remove_async(zilog_t *zilog, uint64_t oid) 1268{ 1269 uint64_t otxg, txg; 1270 itx_async_node_t *ian; 1271 avl_tree_t *t; 1272 avl_index_t where; 1273 list_t clean_list; 1274 itx_t *itx; 1275 1276 ASSERT(oid != 0); 1277 list_create(&clean_list, sizeof (itx_t), offsetof(itx_t, itx_node)); 1278 1279 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1280 otxg = ZILTEST_TXG; 1281 else 1282 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1283 1284 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1285 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1286 1287 mutex_enter(&itxg->itxg_lock); 1288 if (itxg->itxg_txg != txg) { 1289 mutex_exit(&itxg->itxg_lock); 1290 continue; 1291 } 1292 1293 /* 1294 * Locate the object node and append its list. 1295 */ 1296 t = &itxg->itxg_itxs->i_async_tree; 1297 ian = avl_find(t, &oid, &where); 1298 if (ian != NULL) 1299 list_move_tail(&clean_list, &ian->ia_list); 1300 mutex_exit(&itxg->itxg_lock); 1301 } 1302 while ((itx = list_head(&clean_list)) != NULL) { 1303 list_remove(&clean_list, itx); 1304 kmem_free(itx, offsetof(itx_t, itx_lr) + 1305 itx->itx_lr.lrc_reclen); 1306 } 1307 list_destroy(&clean_list); 1308} 1309 1310void 1311zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx) 1312{ 1313 uint64_t txg; 1314 itxg_t *itxg; 1315 itxs_t *itxs, *clean = NULL; 1316 1317 /* 1318 * Object ids can be re-instantiated in the next txg so 1319 * remove any async transactions to avoid future leaks. 1320 * This can happen if a fsync occurs on the re-instantiated 1321 * object for a WR_INDIRECT or WR_NEED_COPY write, which gets 1322 * the new file data and flushes a write record for the old object. 1323 */ 1324 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_REMOVE) 1325 zil_remove_async(zilog, itx->itx_oid); 1326 1327 /* 1328 * Ensure the data of a renamed file is committed before the rename. 1329 */ 1330 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_RENAME) 1331 zil_async_to_sync(zilog, itx->itx_oid); 1332 1333 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) 1334 txg = ZILTEST_TXG; 1335 else 1336 txg = dmu_tx_get_txg(tx); 1337 1338 itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1339 mutex_enter(&itxg->itxg_lock); 1340 itxs = itxg->itxg_itxs; 1341 if (itxg->itxg_txg != txg) { 1342 if (itxs != NULL) { 1343 /* 1344 * The zil_clean callback hasn't got around to cleaning 1345 * this itxg. Save the itxs for release below. 1346 * This should be rare. 1347 */ 1348 clean = itxg->itxg_itxs; 1349 } 1350 itxg->itxg_txg = txg; 1351 itxs = itxg->itxg_itxs = kmem_zalloc(sizeof (itxs_t), KM_SLEEP); 1352 1353 list_create(&itxs->i_sync_list, sizeof (itx_t), 1354 offsetof(itx_t, itx_node)); 1355 avl_create(&itxs->i_async_tree, zil_aitx_compare, 1356 sizeof (itx_async_node_t), 1357 offsetof(itx_async_node_t, ia_node)); 1358 } 1359 if (itx->itx_sync) { 1360 list_insert_tail(&itxs->i_sync_list, itx); 1361 } else { 1362 avl_tree_t *t = &itxs->i_async_tree; 1363 uint64_t foid = ((lr_ooo_t *)&itx->itx_lr)->lr_foid; 1364 itx_async_node_t *ian; 1365 avl_index_t where; 1366 1367 ian = avl_find(t, &foid, &where); 1368 if (ian == NULL) { 1369 ian = kmem_alloc(sizeof (itx_async_node_t), KM_SLEEP); 1370 list_create(&ian->ia_list, sizeof (itx_t), 1371 offsetof(itx_t, itx_node)); 1372 ian->ia_foid = foid; 1373 avl_insert(t, ian, where); 1374 } 1375 list_insert_tail(&ian->ia_list, itx); 1376 } 1377 1378 itx->itx_lr.lrc_txg = dmu_tx_get_txg(tx); 1379 zilog_dirty(zilog, txg); 1380 mutex_exit(&itxg->itxg_lock); 1381 1382 /* Release the old itxs now we've dropped the lock */ 1383 if (clean != NULL) 1384 zil_itxg_clean(clean); 1385} 1386 1387/* 1388 * If there are any in-memory intent log transactions which have now been 1389 * synced then start up a taskq to free them. We should only do this after we 1390 * have written out the uberblocks (i.e. txg has been comitted) so that 1391 * don't inadvertently clean out in-memory log records that would be required 1392 * by zil_commit(). 1393 */ 1394void 1395zil_clean(zilog_t *zilog, uint64_t synced_txg) 1396{ 1397 itxg_t *itxg = &zilog->zl_itxg[synced_txg & TXG_MASK]; 1398 itxs_t *clean_me; 1399 1400 mutex_enter(&itxg->itxg_lock); 1401 if (itxg->itxg_itxs == NULL || itxg->itxg_txg == ZILTEST_TXG) { 1402 mutex_exit(&itxg->itxg_lock); 1403 return; 1404 } 1405 ASSERT3U(itxg->itxg_txg, <=, synced_txg); 1406 ASSERT(itxg->itxg_txg != 0); 1407 ASSERT(zilog->zl_clean_taskq != NULL); 1408 clean_me = itxg->itxg_itxs; 1409 itxg->itxg_itxs = NULL; 1410 itxg->itxg_txg = 0; 1411 mutex_exit(&itxg->itxg_lock); 1412 /* 1413 * Preferably start a task queue to free up the old itxs but 1414 * if taskq_dispatch can't allocate resources to do that then 1415 * free it in-line. This should be rare. Note, using TQ_SLEEP 1416 * created a bad performance problem. 1417 */ 1418 if (taskq_dispatch(zilog->zl_clean_taskq, 1419 (void (*)(void *))zil_itxg_clean, clean_me, TQ_NOSLEEP) == 0) 1420 zil_itxg_clean(clean_me); 1421} 1422 1423/* 1424 * Get the list of itxs to commit into zl_itx_commit_list. 1425 */ 1426static void 1427zil_get_commit_list(zilog_t *zilog) 1428{ 1429 uint64_t otxg, txg; 1430 list_t *commit_list = &zilog->zl_itx_commit_list; 1431 1432 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1433 otxg = ZILTEST_TXG; 1434 else 1435 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1436 1437 /* 1438 * This is inherently racy, since there is nothing to prevent 1439 * the last synced txg from changing. That's okay since we'll 1440 * only commit things in the future. 1441 */ 1442 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1443 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1444 1445 mutex_enter(&itxg->itxg_lock); 1446 if (itxg->itxg_txg != txg) { 1447 mutex_exit(&itxg->itxg_lock); 1448 continue; 1449 } 1450 1451 /* 1452 * If we're adding itx records to the zl_itx_commit_list, 1453 * then the zil better be dirty in this "txg". We can assert 1454 * that here since we're holding the itxg_lock which will 1455 * prevent spa_sync from cleaning it. Once we add the itxs 1456 * to the zl_itx_commit_list we must commit it to disk even 1457 * if it's unnecessary (i.e. the txg was synced). 1458 */ 1459 ASSERT(zilog_is_dirty_in_txg(zilog, txg) || 1460 spa_freeze_txg(zilog->zl_spa) != UINT64_MAX); 1461 list_move_tail(commit_list, &itxg->itxg_itxs->i_sync_list); 1462 1463 mutex_exit(&itxg->itxg_lock); 1464 } 1465} 1466 1467/* 1468 * Move the async itxs for a specified object to commit into sync lists. 1469 */ 1470void 1471zil_async_to_sync(zilog_t *zilog, uint64_t foid) 1472{ 1473 uint64_t otxg, txg; 1474 itx_async_node_t *ian; 1475 avl_tree_t *t; 1476 avl_index_t where; 1477 1478 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1479 otxg = ZILTEST_TXG; 1480 else 1481 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1482 1483 /* 1484 * This is inherently racy, since there is nothing to prevent 1485 * the last synced txg from changing. 1486 */ 1487 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1488 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1489 1490 mutex_enter(&itxg->itxg_lock); 1491 if (itxg->itxg_txg != txg) { 1492 mutex_exit(&itxg->itxg_lock); 1493 continue; 1494 } 1495 1496 /* 1497 * If a foid is specified then find that node and append its 1498 * list. Otherwise walk the tree appending all the lists 1499 * to the sync list. We add to the end rather than the 1500 * beginning to ensure the create has happened. 1501 */ 1502 t = &itxg->itxg_itxs->i_async_tree; 1503 if (foid != 0) { 1504 ian = avl_find(t, &foid, &where); 1505 if (ian != NULL) { 1506 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1507 &ian->ia_list); 1508 } 1509 } else { 1510 void *cookie = NULL; 1511 1512 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1513 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1514 &ian->ia_list); 1515 list_destroy(&ian->ia_list); 1516 kmem_free(ian, sizeof (itx_async_node_t)); 1517 } 1518 } 1519 mutex_exit(&itxg->itxg_lock); 1520 } 1521} 1522 1523static void 1524zil_commit_writer(zilog_t *zilog) 1525{ 1526 uint64_t txg; 1527 itx_t *itx; 1528 lwb_t *lwb; 1529 spa_t *spa = zilog->zl_spa; 1530 int error = 0; 1531 1532 ASSERT(zilog->zl_root_zio == NULL); 1533 1534 mutex_exit(&zilog->zl_lock); 1535 1536 zil_get_commit_list(zilog); 1537 1538 /* 1539 * Return if there's nothing to commit before we dirty the fs by 1540 * calling zil_create(). 1541 */ 1542 if (list_head(&zilog->zl_itx_commit_list) == NULL) { 1543 mutex_enter(&zilog->zl_lock); 1544 return; 1545 } 1546 1547 if (zilog->zl_suspend) { 1548 lwb = NULL; 1549 } else { 1550 lwb = list_tail(&zilog->zl_lwb_list); 1551 if (lwb == NULL) 1552 lwb = zil_create(zilog); 1553 } 1554 1555 DTRACE_PROBE1(zil__cw1, zilog_t *, zilog); 1556 while (itx = list_head(&zilog->zl_itx_commit_list)) { 1557 txg = itx->itx_lr.lrc_txg; 1558 ASSERT3U(txg, !=, 0); 1559 1560 /* 1561 * This is inherently racy and may result in us writing 1562 * out a log block for a txg that was just synced. This is 1563 * ok since we'll end cleaning up that log block the next 1564 * time we call zil_sync(). 1565 */ 1566 if (txg > spa_last_synced_txg(spa) || txg > spa_freeze_txg(spa)) 1567 lwb = zil_lwb_commit(zilog, itx, lwb); 1568 list_remove(&zilog->zl_itx_commit_list, itx); 1569 kmem_free(itx, offsetof(itx_t, itx_lr) 1570 + itx->itx_lr.lrc_reclen); 1571 } 1572 DTRACE_PROBE1(zil__cw2, zilog_t *, zilog); 1573 1574 /* write the last block out */ 1575 if (lwb != NULL && lwb->lwb_zio != NULL) 1576 lwb = zil_lwb_write_start(zilog, lwb, B_TRUE); 1577 1578 zilog->zl_cur_used = 0; 1579 1580 /* 1581 * Wait if necessary for the log blocks to be on stable storage. 1582 */ 1583 if (zilog->zl_root_zio) { 1584 error = zio_wait(zilog->zl_root_zio); 1585 zilog->zl_root_zio = NULL; 1586 zil_flush_vdevs(zilog); 1587 } 1588 1589 if (error || lwb == NULL) 1590 txg_wait_synced(zilog->zl_dmu_pool, 0); 1591 1592 mutex_enter(&zilog->zl_lock); 1593 1594 /* 1595 * Remember the highest committed log sequence number for ztest. 1596 * We only update this value when all the log writes succeeded, 1597 * because ztest wants to ASSERT that it got the whole log chain. 1598 */ 1599 if (error == 0 && lwb != NULL) 1600 zilog->zl_commit_lr_seq = zilog->zl_lr_seq; 1601} 1602 1603/* 1604 * Commit zfs transactions to stable storage. 1605 * If foid is 0 push out all transactions, otherwise push only those 1606 * for that object or might reference that object. 1607 * 1608 * itxs are committed in batches. In a heavily stressed zil there will be 1609 * a commit writer thread who is writing out a bunch of itxs to the log 1610 * for a set of committing threads (cthreads) in the same batch as the writer. 1611 * Those cthreads are all waiting on the same cv for that batch. 1612 * 1613 * There will also be a different and growing batch of threads that are 1614 * waiting to commit (qthreads). When the committing batch completes 1615 * a transition occurs such that the cthreads exit and the qthreads become 1616 * cthreads. One of the new cthreads becomes the writer thread for the 1617 * batch. Any new threads arriving become new qthreads. 1618 * 1619 * Only 2 condition variables are needed and there's no transition 1620 * between the two cvs needed. They just flip-flop between qthreads 1621 * and cthreads. 1622 * 1623 * Using this scheme we can efficiently wakeup up only those threads 1624 * that have been committed. 1625 */ 1626void 1627zil_commit(zilog_t *zilog, uint64_t foid) 1628{ 1629 uint64_t mybatch; 1630 1631 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 1632 return; 1633 1634 /* move the async itxs for the foid to the sync queues */ 1635 zil_async_to_sync(zilog, foid); 1636 1637 mutex_enter(&zilog->zl_lock); 1638 mybatch = zilog->zl_next_batch; 1639 while (zilog->zl_writer) { 1640 cv_wait(&zilog->zl_cv_batch[mybatch & 1], &zilog->zl_lock); 1641 if (mybatch <= zilog->zl_com_batch) { 1642 mutex_exit(&zilog->zl_lock); 1643 return; 1644 } 1645 } 1646 1647 zilog->zl_next_batch++; 1648 zilog->zl_writer = B_TRUE; 1649 zil_commit_writer(zilog); 1650 zilog->zl_com_batch = mybatch; 1651 zilog->zl_writer = B_FALSE; 1652 mutex_exit(&zilog->zl_lock); 1653 1654 /* wake up one thread to become the next writer */ 1655 cv_signal(&zilog->zl_cv_batch[(mybatch+1) & 1]); 1656 1657 /* wake up all threads waiting for this batch to be committed */ 1658 cv_broadcast(&zilog->zl_cv_batch[mybatch & 1]); 1659} 1660 1661/* 1662 * Called in syncing context to free committed log blocks and update log header. 1663 */ 1664void 1665zil_sync(zilog_t *zilog, dmu_tx_t *tx) 1666{ 1667 zil_header_t *zh = zil_header_in_syncing_context(zilog); 1668 uint64_t txg = dmu_tx_get_txg(tx); 1669 spa_t *spa = zilog->zl_spa; 1670 uint64_t *replayed_seq = &zilog->zl_replayed_seq[txg & TXG_MASK]; 1671 lwb_t *lwb; 1672 1673 /* 1674 * We don't zero out zl_destroy_txg, so make sure we don't try 1675 * to destroy it twice. 1676 */ 1677 if (spa_sync_pass(spa) != 1) 1678 return; 1679 1680 mutex_enter(&zilog->zl_lock); 1681 1682 ASSERT(zilog->zl_stop_sync == 0); 1683 1684 if (*replayed_seq != 0) { 1685 ASSERT(zh->zh_replay_seq < *replayed_seq); 1686 zh->zh_replay_seq = *replayed_seq; 1687 *replayed_seq = 0; 1688 } 1689 1690 if (zilog->zl_destroy_txg == txg) { 1691 blkptr_t blk = zh->zh_log; 1692 1693 ASSERT(list_head(&zilog->zl_lwb_list) == NULL); 1694 1695 bzero(zh, sizeof (zil_header_t)); 1696 bzero(zilog->zl_replayed_seq, sizeof (zilog->zl_replayed_seq)); 1697 1698 if (zilog->zl_keep_first) { 1699 /* 1700 * If this block was part of log chain that couldn't 1701 * be claimed because a device was missing during 1702 * zil_claim(), but that device later returns, 1703 * then this block could erroneously appear valid. 1704 * To guard against this, assign a new GUID to the new 1705 * log chain so it doesn't matter what blk points to. 1706 */ 1707 zil_init_log_chain(zilog, &blk); 1708 zh->zh_log = blk; 1709 } 1710 } 1711 1712 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 1713 zh->zh_log = lwb->lwb_blk; 1714 if (lwb->lwb_buf != NULL || lwb->lwb_max_txg > txg) 1715 break; 1716 list_remove(&zilog->zl_lwb_list, lwb); 1717 zio_free_zil(spa, txg, &lwb->lwb_blk); 1718 kmem_cache_free(zil_lwb_cache, lwb); 1719 1720 /* 1721 * If we don't have anything left in the lwb list then 1722 * we've had an allocation failure and we need to zero 1723 * out the zil_header blkptr so that we don't end 1724 * up freeing the same block twice. 1725 */ 1726 if (list_head(&zilog->zl_lwb_list) == NULL) 1727 BP_ZERO(&zh->zh_log); 1728 } 1729 mutex_exit(&zilog->zl_lock); 1730} 1731 1732void 1733zil_init(void) 1734{ 1735 zil_lwb_cache = kmem_cache_create("zil_lwb_cache", 1736 sizeof (struct lwb), 0, NULL, NULL, NULL, NULL, NULL, 0); 1737} 1738 1739void 1740zil_fini(void) 1741{ 1742 kmem_cache_destroy(zil_lwb_cache); 1743} 1744 1745void 1746zil_set_sync(zilog_t *zilog, uint64_t sync) 1747{ 1748 zilog->zl_sync = sync; 1749} 1750 1751void 1752zil_set_logbias(zilog_t *zilog, uint64_t logbias) 1753{ 1754 zilog->zl_logbias = logbias; 1755} 1756 1757zilog_t * 1758zil_alloc(objset_t *os, zil_header_t *zh_phys) 1759{ 1760 zilog_t *zilog; 1761 1762 zilog = kmem_zalloc(sizeof (zilog_t), KM_SLEEP); 1763 1764 zilog->zl_header = zh_phys; 1765 zilog->zl_os = os; 1766 zilog->zl_spa = dmu_objset_spa(os); 1767 zilog->zl_dmu_pool = dmu_objset_pool(os); 1768 zilog->zl_destroy_txg = TXG_INITIAL - 1; 1769 zilog->zl_logbias = dmu_objset_logbias(os); 1770 zilog->zl_sync = dmu_objset_syncprop(os); 1771 zilog->zl_next_batch = 1; 1772 1773 mutex_init(&zilog->zl_lock, NULL, MUTEX_DEFAULT, NULL); 1774 1775 for (int i = 0; i < TXG_SIZE; i++) { 1776 mutex_init(&zilog->zl_itxg[i].itxg_lock, NULL, 1777 MUTEX_DEFAULT, NULL); 1778 } 1779 1780 list_create(&zilog->zl_lwb_list, sizeof (lwb_t), 1781 offsetof(lwb_t, lwb_node)); 1782 1783 list_create(&zilog->zl_itx_commit_list, sizeof (itx_t), 1784 offsetof(itx_t, itx_node)); 1785 1786 mutex_init(&zilog->zl_vdev_lock, NULL, MUTEX_DEFAULT, NULL); 1787 1788 avl_create(&zilog->zl_vdev_tree, zil_vdev_compare, 1789 sizeof (zil_vdev_node_t), offsetof(zil_vdev_node_t, zv_node)); 1790 1791 cv_init(&zilog->zl_cv_writer, NULL, CV_DEFAULT, NULL); 1792 cv_init(&zilog->zl_cv_suspend, NULL, CV_DEFAULT, NULL); 1793 cv_init(&zilog->zl_cv_batch[0], NULL, CV_DEFAULT, NULL); 1794 cv_init(&zilog->zl_cv_batch[1], NULL, CV_DEFAULT, NULL); 1795 1796 return (zilog); 1797} 1798 1799void 1800zil_free(zilog_t *zilog) 1801{ 1802 zilog->zl_stop_sync = 1; 1803 1804 ASSERT0(zilog->zl_suspend); 1805 ASSERT0(zilog->zl_suspending); 1806 1807 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1808 list_destroy(&zilog->zl_lwb_list); 1809 1810 avl_destroy(&zilog->zl_vdev_tree); 1811 mutex_destroy(&zilog->zl_vdev_lock); 1812 1813 ASSERT(list_is_empty(&zilog->zl_itx_commit_list)); 1814 list_destroy(&zilog->zl_itx_commit_list); 1815 1816 for (int i = 0; i < TXG_SIZE; i++) { 1817 /* 1818 * It's possible for an itx to be generated that doesn't dirty 1819 * a txg (e.g. ztest TX_TRUNCATE). So there's no zil_clean() 1820 * callback to remove the entry. We remove those here. 1821 * 1822 * Also free up the ziltest itxs. 1823 */ 1824 if (zilog->zl_itxg[i].itxg_itxs) 1825 zil_itxg_clean(zilog->zl_itxg[i].itxg_itxs); 1826 mutex_destroy(&zilog->zl_itxg[i].itxg_lock); 1827 } 1828 1829 mutex_destroy(&zilog->zl_lock); 1830 1831 cv_destroy(&zilog->zl_cv_writer); 1832 cv_destroy(&zilog->zl_cv_suspend); 1833 cv_destroy(&zilog->zl_cv_batch[0]); 1834 cv_destroy(&zilog->zl_cv_batch[1]); 1835 1836 kmem_free(zilog, sizeof (zilog_t)); 1837} 1838 1839/* 1840 * Open an intent log. 1841 */ 1842zilog_t * 1843zil_open(objset_t *os, zil_get_data_t *get_data) 1844{ 1845 zilog_t *zilog = dmu_objset_zil(os); 1846 1847 ASSERT(zilog->zl_clean_taskq == NULL); 1848 ASSERT(zilog->zl_get_data == NULL); 1849 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1850 1851 zilog->zl_get_data = get_data; 1852 zilog->zl_clean_taskq = taskq_create("zil_clean", 1, minclsyspri, 1853 2, 2, TASKQ_PREPOPULATE); 1854 1855 return (zilog); 1856} 1857 1858/* 1859 * Close an intent log. 1860 */ 1861void 1862zil_close(zilog_t *zilog) 1863{ 1864 lwb_t *lwb; 1865 uint64_t txg = 0; 1866 1867 zil_commit(zilog, 0); /* commit all itx */ 1868 1869 /* 1870 * The lwb_max_txg for the stubby lwb will reflect the last activity 1871 * for the zil. After a txg_wait_synced() on the txg we know all the 1872 * callbacks have occurred that may clean the zil. Only then can we 1873 * destroy the zl_clean_taskq. 1874 */ 1875 mutex_enter(&zilog->zl_lock); 1876 lwb = list_tail(&zilog->zl_lwb_list); 1877 if (lwb != NULL) 1878 txg = lwb->lwb_max_txg; 1879 mutex_exit(&zilog->zl_lock); 1880 if (txg) 1881 txg_wait_synced(zilog->zl_dmu_pool, txg); 1882 1883 if (zilog_is_dirty(zilog)) 1884 zfs_dbgmsg("zil (%p) is dirty, txg %llu", zilog, txg); 1885 VERIFY(!zilog_is_dirty(zilog)); 1886 1887 taskq_destroy(zilog->zl_clean_taskq); 1888 zilog->zl_clean_taskq = NULL; 1889 zilog->zl_get_data = NULL; 1890 1891 /* 1892 * We should have only one LWB left on the list; remove it now. 1893 */ 1894 mutex_enter(&zilog->zl_lock); 1895 lwb = list_head(&zilog->zl_lwb_list); 1896 if (lwb != NULL) { 1897 ASSERT(lwb == list_tail(&zilog->zl_lwb_list)); 1898 list_remove(&zilog->zl_lwb_list, lwb); 1899 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 1900 kmem_cache_free(zil_lwb_cache, lwb); 1901 } 1902 mutex_exit(&zilog->zl_lock); 1903} 1904 1905static char *suspend_tag = "zil suspending"; 1906 1907/* 1908 * Suspend an intent log. While in suspended mode, we still honor 1909 * synchronous semantics, but we rely on txg_wait_synced() to do it. 1910 * On old version pools, we suspend the log briefly when taking a 1911 * snapshot so that it will have an empty intent log. 1912 * 1913 * Long holds are not really intended to be used the way we do here -- 1914 * held for such a short time. A concurrent caller of dsl_dataset_long_held() 1915 * could fail. Therefore we take pains to only put a long hold if it is 1916 * actually necessary. Fortunately, it will only be necessary if the 1917 * objset is currently mounted (or the ZVOL equivalent). In that case it 1918 * will already have a long hold, so we are not really making things any worse. 1919 * 1920 * Ideally, we would locate the existing long-holder (i.e. the zfsvfs_t or 1921 * zvol_state_t), and use their mechanism to prevent their hold from being 1922 * dropped (e.g. VFS_HOLD()). However, that would be even more pain for 1923 * very little gain. 1924 * 1925 * if cookiep == NULL, this does both the suspend & resume. 1926 * Otherwise, it returns with the dataset "long held", and the cookie 1927 * should be passed into zil_resume(). 1928 */ 1929int 1930zil_suspend(const char *osname, void **cookiep) 1931{ 1932 objset_t *os; 1933 zilog_t *zilog; 1934 const zil_header_t *zh; 1935 int error; 1936 1937 error = dmu_objset_hold(osname, suspend_tag, &os); 1938 if (error != 0) 1939 return (error); 1940 zilog = dmu_objset_zil(os); 1941 1942 mutex_enter(&zilog->zl_lock); 1943 zh = zilog->zl_header; 1944 1945 if (zh->zh_flags & ZIL_REPLAY_NEEDED) { /* unplayed log */ 1946 mutex_exit(&zilog->zl_lock); 1947 dmu_objset_rele(os, suspend_tag); 1948 return (SET_ERROR(EBUSY)); 1949 } 1950 1951 /* 1952 * Don't put a long hold in the cases where we can avoid it. This 1953 * is when there is no cookie so we are doing a suspend & resume 1954 * (i.e. called from zil_vdev_offline()), and there's nothing to do 1955 * for the suspend because it's already suspended, or there's no ZIL. 1956 */ 1957 if (cookiep == NULL && !zilog->zl_suspending && 1958 (zilog->zl_suspend > 0 || BP_IS_HOLE(&zh->zh_log))) { 1959 mutex_exit(&zilog->zl_lock); 1960 dmu_objset_rele(os, suspend_tag); 1961 return (0); 1962 } 1963 1964 dsl_dataset_long_hold(dmu_objset_ds(os), suspend_tag); 1965 dsl_pool_rele(dmu_objset_pool(os), suspend_tag); 1966 1967 zilog->zl_suspend++; 1968 1969 if (zilog->zl_suspend > 1) { 1970 /* 1971 * Someone else is already suspending it. 1972 * Just wait for them to finish. 1973 */ 1974 1975 while (zilog->zl_suspending) 1976 cv_wait(&zilog->zl_cv_suspend, &zilog->zl_lock); 1977 mutex_exit(&zilog->zl_lock); 1978 1979 if (cookiep == NULL) 1980 zil_resume(os); 1981 else 1982 *cookiep = os; 1983 return (0); 1984 } 1985 1986 /* 1987 * If there is no pointer to an on-disk block, this ZIL must not 1988 * be active (e.g. filesystem not mounted), so there's nothing 1989 * to clean up. 1990 */ 1991 if (BP_IS_HOLE(&zh->zh_log)) { 1992 ASSERT(cookiep != NULL); /* fast path already handled */ 1993 1994 *cookiep = os; 1995 mutex_exit(&zilog->zl_lock); 1996 return (0); 1997 } 1998 1999 zilog->zl_suspending = B_TRUE; 2000 mutex_exit(&zilog->zl_lock); 2001 2002 zil_commit(zilog, 0); 2003 2004 zil_destroy(zilog, B_FALSE); 2005 2006 mutex_enter(&zilog->zl_lock); 2007 zilog->zl_suspending = B_FALSE; 2008 cv_broadcast(&zilog->zl_cv_suspend); 2009 mutex_exit(&zilog->zl_lock); 2010 2011 if (cookiep == NULL) 2012 zil_resume(os); 2013 else 2014 *cookiep = os; 2015 return (0); 2016} 2017 2018void 2019zil_resume(void *cookie) 2020{ 2021 objset_t *os = cookie; 2022 zilog_t *zilog = dmu_objset_zil(os); 2023 2024 mutex_enter(&zilog->zl_lock); 2025 ASSERT(zilog->zl_suspend != 0); 2026 zilog->zl_suspend--; 2027 mutex_exit(&zilog->zl_lock); 2028 dsl_dataset_long_rele(dmu_objset_ds(os), suspend_tag); 2029 dsl_dataset_rele(dmu_objset_ds(os), suspend_tag); 2030} 2031 2032typedef struct zil_replay_arg { 2033 zil_replay_func_t **zr_replay; 2034 void *zr_arg; 2035 boolean_t zr_byteswap; 2036 char *zr_lr; 2037} zil_replay_arg_t; 2038 2039static int 2040zil_replay_error(zilog_t *zilog, lr_t *lr, int error) 2041{ 2042 char name[ZFS_MAX_DATASET_NAME_LEN]; 2043 2044 zilog->zl_replaying_seq--; /* didn't actually replay this one */ 2045 2046 dmu_objset_name(zilog->zl_os, name); 2047 2048 cmn_err(CE_WARN, "ZFS replay transaction error %d, " 2049 "dataset %s, seq 0x%llx, txtype %llu %s\n", error, name, 2050 (u_longlong_t)lr->lrc_seq, 2051 (u_longlong_t)(lr->lrc_txtype & ~TX_CI), 2052 (lr->lrc_txtype & TX_CI) ? "CI" : ""); 2053 2054 return (error); 2055} 2056 2057static int 2058zil_replay_log_record(zilog_t *zilog, lr_t *lr, void *zra, uint64_t claim_txg) 2059{ 2060 zil_replay_arg_t *zr = zra; 2061 const zil_header_t *zh = zilog->zl_header; 2062 uint64_t reclen = lr->lrc_reclen; 2063 uint64_t txtype = lr->lrc_txtype; 2064 int error = 0; 2065 2066 zilog->zl_replaying_seq = lr->lrc_seq; 2067 2068 if (lr->lrc_seq <= zh->zh_replay_seq) /* already replayed */ 2069 return (0); 2070 2071 if (lr->lrc_txg < claim_txg) /* already committed */ 2072 return (0); 2073 2074 /* Strip case-insensitive bit, still present in log record */ 2075 txtype &= ~TX_CI; 2076 2077 if (txtype == 0 || txtype >= TX_MAX_TYPE) 2078 return (zil_replay_error(zilog, lr, EINVAL)); 2079 2080 /* 2081 * If this record type can be logged out of order, the object 2082 * (lr_foid) may no longer exist. That's legitimate, not an error. 2083 */ 2084 if (TX_OOO(txtype)) { 2085 error = dmu_object_info(zilog->zl_os, 2086 ((lr_ooo_t *)lr)->lr_foid, NULL); 2087 if (error == ENOENT || error == EEXIST) 2088 return (0); 2089 } 2090 2091 /* 2092 * Make a copy of the data so we can revise and extend it. 2093 */ 2094 bcopy(lr, zr->zr_lr, reclen); 2095 2096 /* 2097 * If this is a TX_WRITE with a blkptr, suck in the data. 2098 */ 2099 if (txtype == TX_WRITE && reclen == sizeof (lr_write_t)) { 2100 error = zil_read_log_data(zilog, (lr_write_t *)lr, 2101 zr->zr_lr + reclen); 2102 if (error != 0) 2103 return (zil_replay_error(zilog, lr, error)); 2104 } 2105 2106 /* 2107 * The log block containing this lr may have been byteswapped 2108 * so that we can easily examine common fields like lrc_txtype. 2109 * However, the log is a mix of different record types, and only the 2110 * replay vectors know how to byteswap their records. Therefore, if 2111 * the lr was byteswapped, undo it before invoking the replay vector. 2112 */ 2113 if (zr->zr_byteswap) 2114 byteswap_uint64_array(zr->zr_lr, reclen); 2115 2116 /* 2117 * We must now do two things atomically: replay this log record, 2118 * and update the log header sequence number to reflect the fact that 2119 * we did so. At the end of each replay function the sequence number 2120 * is updated if we are in replay mode. 2121 */ 2122 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, zr->zr_byteswap); 2123 if (error != 0) { 2124 /* 2125 * The DMU's dnode layer doesn't see removes until the txg 2126 * commits, so a subsequent claim can spuriously fail with 2127 * EEXIST. So if we receive any error we try syncing out 2128 * any removes then retry the transaction. Note that we 2129 * specify B_FALSE for byteswap now, so we don't do it twice. 2130 */ 2131 txg_wait_synced(spa_get_dsl(zilog->zl_spa), 0); 2132 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, B_FALSE); 2133 if (error != 0) 2134 return (zil_replay_error(zilog, lr, error)); 2135 } 2136 return (0); 2137} 2138 2139/* ARGSUSED */ 2140static int 2141zil_incr_blks(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 2142{ 2143 zilog->zl_replay_blks++; 2144 2145 return (0); 2146} 2147 2148/* 2149 * If this dataset has a non-empty intent log, replay it and destroy it. 2150 */ 2151void 2152zil_replay(objset_t *os, void *arg, zil_replay_func_t *replay_func[TX_MAX_TYPE]) 2153{ 2154 zilog_t *zilog = dmu_objset_zil(os); 2155 const zil_header_t *zh = zilog->zl_header; 2156 zil_replay_arg_t zr; 2157 2158 if ((zh->zh_flags & ZIL_REPLAY_NEEDED) == 0) { 2159 zil_destroy(zilog, B_TRUE); 2160 return; 2161 } 2162 2163 zr.zr_replay = replay_func; 2164 zr.zr_arg = arg; 2165 zr.zr_byteswap = BP_SHOULD_BYTESWAP(&zh->zh_log); 2166 zr.zr_lr = kmem_alloc(2 * SPA_MAXBLOCKSIZE, KM_SLEEP); 2167 2168 /* 2169 * Wait for in-progress removes to sync before starting replay. 2170 */ 2171 txg_wait_synced(zilog->zl_dmu_pool, 0); 2172 2173 zilog->zl_replay = B_TRUE; 2174 zilog->zl_replay_time = ddi_get_lbolt(); 2175 ASSERT(zilog->zl_replay_blks == 0); 2176 (void) zil_parse(zilog, zil_incr_blks, zil_replay_log_record, &zr, 2177 zh->zh_claim_txg); 2178 kmem_free(zr.zr_lr, 2 * SPA_MAXBLOCKSIZE); 2179 2180 zil_destroy(zilog, B_FALSE); 2181 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 2182 zilog->zl_replay = B_FALSE; 2183} 2184 2185boolean_t 2186zil_replaying(zilog_t *zilog, dmu_tx_t *tx) 2187{ 2188 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 2189 return (B_TRUE); 2190 2191 if (zilog->zl_replay) { 2192 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 2193 zilog->zl_replayed_seq[dmu_tx_get_txg(tx) & TXG_MASK] = 2194 zilog->zl_replaying_seq; 2195 return (B_TRUE); 2196 } 2197 2198 return (B_FALSE); 2199} 2200 2201/* ARGSUSED */ 2202int 2203zil_vdev_offline(const char *osname, void *arg) 2204{ 2205 int error; 2206 2207 error = zil_suspend(osname, NULL); 2208 if (error != 0) 2209 return (SET_ERROR(EEXIST)); 2210 return (0); 2211} 2212