zil.c revision 247406
10SN/A/* 21358SN/A * CDDL HEADER START 30SN/A * 40SN/A * The contents of this file are subject to the terms of the 50SN/A * Common Development and Distribution License (the "License"). 60SN/A * You may not use this file except in compliance with the License. 7553SN/A * 80SN/A * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9553SN/A * or http://www.opensolaris.org/os/licensing. 100SN/A * See the License for the specific language governing permissions 110SN/A * and limitations under the License. 120SN/A * 130SN/A * When distributing Covered Code, include this CDDL HEADER in each 140SN/A * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 150SN/A * If applicable, add the following below this CDDL HEADER, with the 160SN/A * fields enclosed by brackets "[]" replaced with your own identifying 170SN/A * information: Portions Copyright [yyyy] [name of copyright owner] 180SN/A * 190SN/A * CDDL HEADER END 200SN/A */ 21553SN/A/* 22553SN/A * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23553SN/A * Copyright (c) 2012 by Delphix. All rights reserved. 240SN/A */ 250SN/A 263386Sjjg/* Portions Copyright 2010 Robert Milkowski */ 270SN/A 280SN/A#include <sys/zfs_context.h> 290SN/A#include <sys/spa.h> 301442SN/A#include <sys/dmu.h> 310SN/A#include <sys/zap.h> 320SN/A#include <sys/arc.h> 330SN/A#include <sys/stat.h> 340SN/A#include <sys/resource.h> 350SN/A#include <sys/zil.h> 360SN/A#include <sys/zil_impl.h> 370SN/A#include <sys/dsl_dataset.h> 380SN/A#include <sys/vdev_impl.h> 391358SN/A#include <sys/dmu_tx.h> 401358SN/A#include <sys/dsl_pool.h> 411358SN/A 421358SN/A/* 431358SN/A * The zfs intent log (ZIL) saves transaction records of system calls 440SN/A * that change the file system in memory with enough information 450SN/A * to be able to replay them. These are stored in memory until 460SN/A * either the DMU transaction group (txg) commits them to the stable pool 470SN/A * and they can be discarded, or they are flushed to the stable log 480SN/A * (also in the pool) due to a fsync, O_DSYNC or other synchronous 490SN/A * requirement. In the event of a panic or power fail then those log 500SN/A * records (transactions) are replayed. 510SN/A * 523445Sjjg * There is one ZIL per file system. Its on-disk (pool) format consists 530SN/A * of 3 parts: 540SN/A * 550SN/A * - ZIL header 560SN/A * - ZIL blocks 570SN/A * - ZIL records 580SN/A * 590SN/A * A log record holds a system call transaction. Log blocks can 601442SN/A * hold many log records and the blocks are chained together. 611442SN/A * Each ZIL block contains a block pointer (blkptr_t) to the next 620SN/A * ZIL block in the chain. The ZIL header points to the first 630SN/A * block in the chain. Note there is not a fixed place in the pool 640SN/A * to hold blocks. They are dynamically allocated and freed as 650SN/A * needed from the blocks available. Figure X shows the ZIL structure: 660SN/A */ 670SN/A 680SN/A/* 69 * This global ZIL switch affects all pools 70 */ 71int zil_replay_disable = 0; /* disable intent logging replay */ 72SYSCTL_DECL(_vfs_zfs); 73TUNABLE_INT("vfs.zfs.zil_replay_disable", &zil_replay_disable); 74SYSCTL_INT(_vfs_zfs, OID_AUTO, zil_replay_disable, CTLFLAG_RW, 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; 83TUNABLE_INT("vfs.zfs.cache_flush_disable", &zfs_nocacheflush); 84SYSCTL_INT(_vfs_zfs, OID_AUTO, cache_flush_disable, CTLFLAG_RDTUN, 85 &zfs_nocacheflush, 0, "Disable cache flush"); 86 87static kmem_cache_t *zil_lwb_cache; 88 89static void zil_async_to_sync(zilog_t *zilog, uint64_t foid); 90 91#define LWB_EMPTY(lwb) ((BP_GET_LSIZE(&lwb->lwb_blk) - \ 92 sizeof (zil_chain_t)) == (lwb->lwb_sz - lwb->lwb_nused)) 93 94 95/* 96 * ziltest is by and large an ugly hack, but very useful in 97 * checking replay without tedious work. 98 * When running ziltest we want to keep all itx's and so maintain 99 * a single list in the zl_itxg[] that uses a high txg: ZILTEST_TXG 100 * We subtract TXG_CONCURRENT_STATES to allow for common code. 101 */ 102#define ZILTEST_TXG (UINT64_MAX - TXG_CONCURRENT_STATES) 103 104static int 105zil_bp_compare(const void *x1, const void *x2) 106{ 107 const dva_t *dva1 = &((zil_bp_node_t *)x1)->zn_dva; 108 const dva_t *dva2 = &((zil_bp_node_t *)x2)->zn_dva; 109 110 if (DVA_GET_VDEV(dva1) < DVA_GET_VDEV(dva2)) 111 return (-1); 112 if (DVA_GET_VDEV(dva1) > DVA_GET_VDEV(dva2)) 113 return (1); 114 115 if (DVA_GET_OFFSET(dva1) < DVA_GET_OFFSET(dva2)) 116 return (-1); 117 if (DVA_GET_OFFSET(dva1) > DVA_GET_OFFSET(dva2)) 118 return (1); 119 120 return (0); 121} 122 123static void 124zil_bp_tree_init(zilog_t *zilog) 125{ 126 avl_create(&zilog->zl_bp_tree, zil_bp_compare, 127 sizeof (zil_bp_node_t), offsetof(zil_bp_node_t, zn_node)); 128} 129 130static void 131zil_bp_tree_fini(zilog_t *zilog) 132{ 133 avl_tree_t *t = &zilog->zl_bp_tree; 134 zil_bp_node_t *zn; 135 void *cookie = NULL; 136 137 while ((zn = avl_destroy_nodes(t, &cookie)) != NULL) 138 kmem_free(zn, sizeof (zil_bp_node_t)); 139 140 avl_destroy(t); 141} 142 143int 144zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp) 145{ 146 avl_tree_t *t = &zilog->zl_bp_tree; 147 const dva_t *dva = BP_IDENTITY(bp); 148 zil_bp_node_t *zn; 149 avl_index_t where; 150 151 if (avl_find(t, dva, &where) != NULL) 152 return (EEXIST); 153 154 zn = kmem_alloc(sizeof (zil_bp_node_t), KM_SLEEP); 155 zn->zn_dva = *dva; 156 avl_insert(t, zn, where); 157 158 return (0); 159} 160 161static zil_header_t * 162zil_header_in_syncing_context(zilog_t *zilog) 163{ 164 return ((zil_header_t *)zilog->zl_header); 165} 166 167static void 168zil_init_log_chain(zilog_t *zilog, blkptr_t *bp) 169{ 170 zio_cksum_t *zc = &bp->blk_cksum; 171 172 zc->zc_word[ZIL_ZC_GUID_0] = spa_get_random(-1ULL); 173 zc->zc_word[ZIL_ZC_GUID_1] = spa_get_random(-1ULL); 174 zc->zc_word[ZIL_ZC_OBJSET] = dmu_objset_id(zilog->zl_os); 175 zc->zc_word[ZIL_ZC_SEQ] = 1ULL; 176} 177 178/* 179 * Read a log block and make sure it's valid. 180 */ 181static int 182zil_read_log_block(zilog_t *zilog, const blkptr_t *bp, blkptr_t *nbp, void *dst, 183 char **end) 184{ 185 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 186 uint32_t aflags = ARC_WAIT; 187 arc_buf_t *abuf = NULL; 188 zbookmark_t zb; 189 int error; 190 191 if (zilog->zl_header->zh_claim_txg == 0) 192 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 193 194 if (!(zilog->zl_header->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 195 zio_flags |= ZIO_FLAG_SPECULATIVE; 196 197 SET_BOOKMARK(&zb, bp->blk_cksum.zc_word[ZIL_ZC_OBJSET], 198 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); 199 200 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 201 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 202 203 if (error == 0) { 204 zio_cksum_t cksum = bp->blk_cksum; 205 206 /* 207 * Validate the checksummed log block. 208 * 209 * Sequence numbers should be... sequential. The checksum 210 * verifier for the next block should be bp's checksum plus 1. 211 * 212 * Also check the log chain linkage and size used. 213 */ 214 cksum.zc_word[ZIL_ZC_SEQ]++; 215 216 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 217 zil_chain_t *zilc = abuf->b_data; 218 char *lr = (char *)(zilc + 1); 219 uint64_t len = zilc->zc_nused - sizeof (zil_chain_t); 220 221 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 222 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk)) { 223 error = ECKSUM; 224 } else { 225 bcopy(lr, dst, len); 226 *end = (char *)dst + len; 227 *nbp = zilc->zc_next_blk; 228 } 229 } else { 230 char *lr = abuf->b_data; 231 uint64_t size = BP_GET_LSIZE(bp); 232 zil_chain_t *zilc = (zil_chain_t *)(lr + size) - 1; 233 234 if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, 235 sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk) || 236 (zilc->zc_nused > (size - sizeof (*zilc)))) { 237 error = ECKSUM; 238 } else { 239 bcopy(lr, dst, zilc->zc_nused); 240 *end = (char *)dst + zilc->zc_nused; 241 *nbp = zilc->zc_next_blk; 242 } 243 } 244 245 VERIFY(arc_buf_remove_ref(abuf, &abuf) == 1); 246 } 247 248 return (error); 249} 250 251/* 252 * Read a TX_WRITE log data block. 253 */ 254static int 255zil_read_log_data(zilog_t *zilog, const lr_write_t *lr, void *wbuf) 256{ 257 enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; 258 const blkptr_t *bp = &lr->lr_blkptr; 259 uint32_t aflags = ARC_WAIT; 260 arc_buf_t *abuf = NULL; 261 zbookmark_t zb; 262 int error; 263 264 if (BP_IS_HOLE(bp)) { 265 if (wbuf != NULL) 266 bzero(wbuf, MAX(BP_GET_LSIZE(bp), lr->lr_length)); 267 return (0); 268 } 269 270 if (zilog->zl_header->zh_claim_txg == 0) 271 zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; 272 273 SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os), lr->lr_foid, 274 ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp)); 275 276 error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, 277 ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); 278 279 if (error == 0) { 280 if (wbuf != NULL) 281 bcopy(abuf->b_data, wbuf, arc_buf_size(abuf)); 282 (void) arc_buf_remove_ref(abuf, &abuf); 283 } 284 285 return (error); 286} 287 288/* 289 * Parse the intent log, and call parse_func for each valid record within. 290 */ 291int 292zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func, 293 zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg) 294{ 295 const zil_header_t *zh = zilog->zl_header; 296 boolean_t claimed = !!zh->zh_claim_txg; 297 uint64_t claim_blk_seq = claimed ? zh->zh_claim_blk_seq : UINT64_MAX; 298 uint64_t claim_lr_seq = claimed ? zh->zh_claim_lr_seq : UINT64_MAX; 299 uint64_t max_blk_seq = 0; 300 uint64_t max_lr_seq = 0; 301 uint64_t blk_count = 0; 302 uint64_t lr_count = 0; 303 blkptr_t blk, next_blk; 304 char *lrbuf, *lrp; 305 int error = 0; 306 307 /* 308 * Old logs didn't record the maximum zh_claim_lr_seq. 309 */ 310 if (!(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) 311 claim_lr_seq = UINT64_MAX; 312 313 /* 314 * Starting at the block pointed to by zh_log we read the log chain. 315 * For each block in the chain we strongly check that block to 316 * ensure its validity. We stop when an invalid block is found. 317 * For each block pointer in the chain we call parse_blk_func(). 318 * For each record in each valid block we call parse_lr_func(). 319 * If the log has been claimed, stop if we encounter a sequence 320 * number greater than the highest claimed sequence number. 321 */ 322 lrbuf = zio_buf_alloc(SPA_MAXBLOCKSIZE); 323 zil_bp_tree_init(zilog); 324 325 for (blk = zh->zh_log; !BP_IS_HOLE(&blk); blk = next_blk) { 326 uint64_t blk_seq = blk.blk_cksum.zc_word[ZIL_ZC_SEQ]; 327 int reclen; 328 char *end; 329 330 if (blk_seq > claim_blk_seq) 331 break; 332 if ((error = parse_blk_func(zilog, &blk, arg, txg)) != 0) 333 break; 334 ASSERT3U(max_blk_seq, <, blk_seq); 335 max_blk_seq = blk_seq; 336 blk_count++; 337 338 if (max_lr_seq == claim_lr_seq && max_blk_seq == claim_blk_seq) 339 break; 340 341 error = zil_read_log_block(zilog, &blk, &next_blk, lrbuf, &end); 342 if (error) 343 break; 344 345 for (lrp = lrbuf; lrp < end; lrp += reclen) { 346 lr_t *lr = (lr_t *)lrp; 347 reclen = lr->lrc_reclen; 348 ASSERT3U(reclen, >=, sizeof (lr_t)); 349 if (lr->lrc_seq > claim_lr_seq) 350 goto done; 351 if ((error = parse_lr_func(zilog, lr, arg, txg)) != 0) 352 goto done; 353 ASSERT3U(max_lr_seq, <, lr->lrc_seq); 354 max_lr_seq = lr->lrc_seq; 355 lr_count++; 356 } 357 } 358done: 359 zilog->zl_parse_error = error; 360 zilog->zl_parse_blk_seq = max_blk_seq; 361 zilog->zl_parse_lr_seq = max_lr_seq; 362 zilog->zl_parse_blk_count = blk_count; 363 zilog->zl_parse_lr_count = lr_count; 364 365 ASSERT(!claimed || !(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID) || 366 (max_blk_seq == claim_blk_seq && max_lr_seq == claim_lr_seq)); 367 368 zil_bp_tree_fini(zilog); 369 zio_buf_free(lrbuf, SPA_MAXBLOCKSIZE); 370 371 return (error); 372} 373 374static int 375zil_claim_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t first_txg) 376{ 377 /* 378 * Claim log block if not already committed and not already claimed. 379 * If tx == NULL, just verify that the block is claimable. 380 */ 381 if (bp->blk_birth < first_txg || zil_bp_tree_add(zilog, bp) != 0) 382 return (0); 383 384 return (zio_wait(zio_claim(NULL, zilog->zl_spa, 385 tx == NULL ? 0 : first_txg, bp, spa_claim_notify, NULL, 386 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB))); 387} 388 389static int 390zil_claim_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t first_txg) 391{ 392 lr_write_t *lr = (lr_write_t *)lrc; 393 int error; 394 395 if (lrc->lrc_txtype != TX_WRITE) 396 return (0); 397 398 /* 399 * If the block is not readable, don't claim it. This can happen 400 * in normal operation when a log block is written to disk before 401 * some of the dmu_sync() blocks it points to. In this case, the 402 * transaction cannot have been committed to anyone (we would have 403 * waited for all writes to be stable first), so it is semantically 404 * correct to declare this the end of the log. 405 */ 406 if (lr->lr_blkptr.blk_birth >= first_txg && 407 (error = zil_read_log_data(zilog, lr, NULL)) != 0) 408 return (error); 409 return (zil_claim_log_block(zilog, &lr->lr_blkptr, tx, first_txg)); 410} 411 412/* ARGSUSED */ 413static int 414zil_free_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t claim_txg) 415{ 416 zio_free_zil(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 417 418 return (0); 419} 420 421static int 422zil_free_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t claim_txg) 423{ 424 lr_write_t *lr = (lr_write_t *)lrc; 425 blkptr_t *bp = &lr->lr_blkptr; 426 427 /* 428 * If we previously claimed it, we need to free it. 429 */ 430 if (claim_txg != 0 && lrc->lrc_txtype == TX_WRITE && 431 bp->blk_birth >= claim_txg && zil_bp_tree_add(zilog, bp) == 0) 432 zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp); 433 434 return (0); 435} 436 437static lwb_t * 438zil_alloc_lwb(zilog_t *zilog, blkptr_t *bp, uint64_t txg) 439{ 440 lwb_t *lwb; 441 442 lwb = kmem_cache_alloc(zil_lwb_cache, KM_SLEEP); 443 lwb->lwb_zilog = zilog; 444 lwb->lwb_blk = *bp; 445 lwb->lwb_buf = zio_buf_alloc(BP_GET_LSIZE(bp)); 446 lwb->lwb_max_txg = txg; 447 lwb->lwb_zio = NULL; 448 lwb->lwb_tx = NULL; 449 if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { 450 lwb->lwb_nused = sizeof (zil_chain_t); 451 lwb->lwb_sz = BP_GET_LSIZE(bp); 452 } else { 453 lwb->lwb_nused = 0; 454 lwb->lwb_sz = BP_GET_LSIZE(bp) - sizeof (zil_chain_t); 455 } 456 457 mutex_enter(&zilog->zl_lock); 458 list_insert_tail(&zilog->zl_lwb_list, lwb); 459 mutex_exit(&zilog->zl_lock); 460 461 return (lwb); 462} 463 464/* 465 * Called when we create in-memory log transactions so that we know 466 * to cleanup the itxs at the end of spa_sync(). 467 */ 468void 469zilog_dirty(zilog_t *zilog, uint64_t txg) 470{ 471 dsl_pool_t *dp = zilog->zl_dmu_pool; 472 dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); 473 474 if (dsl_dataset_is_snapshot(ds)) 475 panic("dirtying snapshot!"); 476 477 if (txg_list_add(&dp->dp_dirty_zilogs, zilog, txg) == 0) { 478 /* up the hold count until we can be written out */ 479 dmu_buf_add_ref(ds->ds_dbuf, zilog); 480 } 481} 482 483boolean_t 484zilog_is_dirty(zilog_t *zilog) 485{ 486 dsl_pool_t *dp = zilog->zl_dmu_pool; 487 488 for (int t = 0; t < TXG_SIZE; t++) { 489 if (txg_list_member(&dp->dp_dirty_zilogs, zilog, t)) 490 return (B_TRUE); 491 } 492 return (B_FALSE); 493} 494 495/* 496 * Create an on-disk intent log. 497 */ 498static lwb_t * 499zil_create(zilog_t *zilog) 500{ 501 const zil_header_t *zh = zilog->zl_header; 502 lwb_t *lwb = NULL; 503 uint64_t txg = 0; 504 dmu_tx_t *tx = NULL; 505 blkptr_t blk; 506 int error = 0; 507 508 /* 509 * Wait for any previous destroy to complete. 510 */ 511 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 512 513 ASSERT(zh->zh_claim_txg == 0); 514 ASSERT(zh->zh_replay_seq == 0); 515 516 blk = zh->zh_log; 517 518 /* 519 * Allocate an initial log block if: 520 * - there isn't one already 521 * - the existing block is the wrong endianess 522 */ 523 if (BP_IS_HOLE(&blk) || BP_SHOULD_BYTESWAP(&blk)) { 524 tx = dmu_tx_create(zilog->zl_os); 525 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 526 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 527 txg = dmu_tx_get_txg(tx); 528 529 if (!BP_IS_HOLE(&blk)) { 530 zio_free_zil(zilog->zl_spa, txg, &blk); 531 BP_ZERO(&blk); 532 } 533 534 error = zio_alloc_zil(zilog->zl_spa, txg, &blk, NULL, 535 ZIL_MIN_BLKSZ, zilog->zl_logbias == ZFS_LOGBIAS_LATENCY); 536 537 if (error == 0) 538 zil_init_log_chain(zilog, &blk); 539 } 540 541 /* 542 * Allocate a log write buffer (lwb) for the first log block. 543 */ 544 if (error == 0) 545 lwb = zil_alloc_lwb(zilog, &blk, txg); 546 547 /* 548 * If we just allocated the first log block, commit our transaction 549 * and wait for zil_sync() to stuff the block poiner into zh_log. 550 * (zh is part of the MOS, so we cannot modify it in open context.) 551 */ 552 if (tx != NULL) { 553 dmu_tx_commit(tx); 554 txg_wait_synced(zilog->zl_dmu_pool, txg); 555 } 556 557 ASSERT(bcmp(&blk, &zh->zh_log, sizeof (blk)) == 0); 558 559 return (lwb); 560} 561 562/* 563 * In one tx, free all log blocks and clear the log header. 564 * If keep_first is set, then we're replaying a log with no content. 565 * We want to keep the first block, however, so that the first 566 * synchronous transaction doesn't require a txg_wait_synced() 567 * in zil_create(). We don't need to txg_wait_synced() here either 568 * when keep_first is set, because both zil_create() and zil_destroy() 569 * will wait for any in-progress destroys to complete. 570 */ 571void 572zil_destroy(zilog_t *zilog, boolean_t keep_first) 573{ 574 const zil_header_t *zh = zilog->zl_header; 575 lwb_t *lwb; 576 dmu_tx_t *tx; 577 uint64_t txg; 578 579 /* 580 * Wait for any previous destroy to complete. 581 */ 582 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 583 584 zilog->zl_old_header = *zh; /* debugging aid */ 585 586 if (BP_IS_HOLE(&zh->zh_log)) 587 return; 588 589 tx = dmu_tx_create(zilog->zl_os); 590 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 591 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 592 txg = dmu_tx_get_txg(tx); 593 594 mutex_enter(&zilog->zl_lock); 595 596 ASSERT3U(zilog->zl_destroy_txg, <, txg); 597 zilog->zl_destroy_txg = txg; 598 zilog->zl_keep_first = keep_first; 599 600 if (!list_is_empty(&zilog->zl_lwb_list)) { 601 ASSERT(zh->zh_claim_txg == 0); 602 VERIFY(!keep_first); 603 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 604 list_remove(&zilog->zl_lwb_list, lwb); 605 if (lwb->lwb_buf != NULL) 606 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 607 zio_free_zil(zilog->zl_spa, txg, &lwb->lwb_blk); 608 kmem_cache_free(zil_lwb_cache, lwb); 609 } 610 } else if (!keep_first) { 611 zil_destroy_sync(zilog, tx); 612 } 613 mutex_exit(&zilog->zl_lock); 614 615 dmu_tx_commit(tx); 616} 617 618void 619zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx) 620{ 621 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 622 (void) zil_parse(zilog, zil_free_log_block, 623 zil_free_log_record, tx, zilog->zl_header->zh_claim_txg); 624} 625 626int 627zil_claim(const char *osname, void *txarg) 628{ 629 dmu_tx_t *tx = txarg; 630 uint64_t first_txg = dmu_tx_get_txg(tx); 631 zilog_t *zilog; 632 zil_header_t *zh; 633 objset_t *os; 634 int error; 635 636 error = dmu_objset_hold(osname, FTAG, &os); 637 if (error) { 638 cmn_err(CE_WARN, "can't open objset for %s", osname); 639 return (0); 640 } 641 642 zilog = dmu_objset_zil(os); 643 zh = zil_header_in_syncing_context(zilog); 644 645 if (spa_get_log_state(zilog->zl_spa) == SPA_LOG_CLEAR) { 646 if (!BP_IS_HOLE(&zh->zh_log)) 647 zio_free_zil(zilog->zl_spa, first_txg, &zh->zh_log); 648 BP_ZERO(&zh->zh_log); 649 dsl_dataset_dirty(dmu_objset_ds(os), tx); 650 dmu_objset_rele(os, FTAG); 651 return (0); 652 } 653 654 /* 655 * Claim all log blocks if we haven't already done so, and remember 656 * the highest claimed sequence number. This ensures that if we can 657 * read only part of the log now (e.g. due to a missing device), 658 * but we can read the entire log later, we will not try to replay 659 * or destroy beyond the last block we successfully claimed. 660 */ 661 ASSERT3U(zh->zh_claim_txg, <=, first_txg); 662 if (zh->zh_claim_txg == 0 && !BP_IS_HOLE(&zh->zh_log)) { 663 (void) zil_parse(zilog, zil_claim_log_block, 664 zil_claim_log_record, tx, first_txg); 665 zh->zh_claim_txg = first_txg; 666 zh->zh_claim_blk_seq = zilog->zl_parse_blk_seq; 667 zh->zh_claim_lr_seq = zilog->zl_parse_lr_seq; 668 if (zilog->zl_parse_lr_count || zilog->zl_parse_blk_count > 1) 669 zh->zh_flags |= ZIL_REPLAY_NEEDED; 670 zh->zh_flags |= ZIL_CLAIM_LR_SEQ_VALID; 671 dsl_dataset_dirty(dmu_objset_ds(os), tx); 672 } 673 674 ASSERT3U(first_txg, ==, (spa_last_synced_txg(zilog->zl_spa) + 1)); 675 dmu_objset_rele(os, FTAG); 676 return (0); 677} 678 679/* 680 * Check the log by walking the log chain. 681 * Checksum errors are ok as they indicate the end of the chain. 682 * Any other error (no device or read failure) returns an error. 683 */ 684int 685zil_check_log_chain(const char *osname, void *tx) 686{ 687 zilog_t *zilog; 688 objset_t *os; 689 blkptr_t *bp; 690 int error; 691 692 ASSERT(tx == NULL); 693 694 error = dmu_objset_hold(osname, FTAG, &os); 695 if (error) { 696 cmn_err(CE_WARN, "can't open objset for %s", osname); 697 return (0); 698 } 699 700 zilog = dmu_objset_zil(os); 701 bp = (blkptr_t *)&zilog->zl_header->zh_log; 702 703 /* 704 * Check the first block and determine if it's on a log device 705 * which may have been removed or faulted prior to loading this 706 * pool. If so, there's no point in checking the rest of the log 707 * as its content should have already been synced to the pool. 708 */ 709 if (!BP_IS_HOLE(bp)) { 710 vdev_t *vd; 711 boolean_t valid = B_TRUE; 712 713 spa_config_enter(os->os_spa, SCL_STATE, FTAG, RW_READER); 714 vd = vdev_lookup_top(os->os_spa, DVA_GET_VDEV(&bp->blk_dva[0])); 715 if (vd->vdev_islog && vdev_is_dead(vd)) 716 valid = vdev_log_state_valid(vd); 717 spa_config_exit(os->os_spa, SCL_STATE, FTAG); 718 719 if (!valid) { 720 dmu_objset_rele(os, FTAG); 721 return (0); 722 } 723 } 724 725 /* 726 * Because tx == NULL, zil_claim_log_block() will not actually claim 727 * any blocks, but just determine whether it is possible to do so. 728 * In addition to checking the log chain, zil_claim_log_block() 729 * will invoke zio_claim() with a done func of spa_claim_notify(), 730 * which will update spa_max_claim_txg. See spa_load() for details. 731 */ 732 error = zil_parse(zilog, zil_claim_log_block, zil_claim_log_record, tx, 733 zilog->zl_header->zh_claim_txg ? -1ULL : spa_first_txg(os->os_spa)); 734 735 dmu_objset_rele(os, FTAG); 736 737 return ((error == ECKSUM || error == ENOENT) ? 0 : error); 738} 739 740static int 741zil_vdev_compare(const void *x1, const void *x2) 742{ 743 const uint64_t v1 = ((zil_vdev_node_t *)x1)->zv_vdev; 744 const uint64_t v2 = ((zil_vdev_node_t *)x2)->zv_vdev; 745 746 if (v1 < v2) 747 return (-1); 748 if (v1 > v2) 749 return (1); 750 751 return (0); 752} 753 754void 755zil_add_block(zilog_t *zilog, const blkptr_t *bp) 756{ 757 avl_tree_t *t = &zilog->zl_vdev_tree; 758 avl_index_t where; 759 zil_vdev_node_t *zv, zvsearch; 760 int ndvas = BP_GET_NDVAS(bp); 761 int i; 762 763 if (zfs_nocacheflush) 764 return; 765 766 ASSERT(zilog->zl_writer); 767 768 /* 769 * Even though we're zl_writer, we still need a lock because the 770 * zl_get_data() callbacks may have dmu_sync() done callbacks 771 * that will run concurrently. 772 */ 773 mutex_enter(&zilog->zl_vdev_lock); 774 for (i = 0; i < ndvas; i++) { 775 zvsearch.zv_vdev = DVA_GET_VDEV(&bp->blk_dva[i]); 776 if (avl_find(t, &zvsearch, &where) == NULL) { 777 zv = kmem_alloc(sizeof (*zv), KM_SLEEP); 778 zv->zv_vdev = zvsearch.zv_vdev; 779 avl_insert(t, zv, where); 780 } 781 } 782 mutex_exit(&zilog->zl_vdev_lock); 783} 784 785static void 786zil_flush_vdevs(zilog_t *zilog) 787{ 788 spa_t *spa = zilog->zl_spa; 789 avl_tree_t *t = &zilog->zl_vdev_tree; 790 void *cookie = NULL; 791 zil_vdev_node_t *zv; 792 zio_t *zio; 793 794 ASSERT(zilog->zl_writer); 795 796 /* 797 * We don't need zl_vdev_lock here because we're the zl_writer, 798 * and all zl_get_data() callbacks are done. 799 */ 800 if (avl_numnodes(t) == 0) 801 return; 802 803 spa_config_enter(spa, SCL_STATE, FTAG, RW_READER); 804 805 zio = zio_root(spa, NULL, NULL, ZIO_FLAG_CANFAIL); 806 807 while ((zv = avl_destroy_nodes(t, &cookie)) != NULL) { 808 vdev_t *vd = vdev_lookup_top(spa, zv->zv_vdev); 809 if (vd != NULL) 810 zio_flush(zio, vd); 811 kmem_free(zv, sizeof (*zv)); 812 } 813 814 /* 815 * Wait for all the flushes to complete. Not all devices actually 816 * support the DKIOCFLUSHWRITECACHE ioctl, so it's OK if it fails. 817 */ 818 (void) zio_wait(zio); 819 820 spa_config_exit(spa, SCL_STATE, FTAG); 821} 822 823/* 824 * Function called when a log block write completes 825 */ 826static void 827zil_lwb_write_done(zio_t *zio) 828{ 829 lwb_t *lwb = zio->io_private; 830 zilog_t *zilog = lwb->lwb_zilog; 831 dmu_tx_t *tx = lwb->lwb_tx; 832 833 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); 834 ASSERT(BP_GET_TYPE(zio->io_bp) == DMU_OT_INTENT_LOG); 835 ASSERT(BP_GET_LEVEL(zio->io_bp) == 0); 836 ASSERT(BP_GET_BYTEORDER(zio->io_bp) == ZFS_HOST_BYTEORDER); 837 ASSERT(!BP_IS_GANG(zio->io_bp)); 838 ASSERT(!BP_IS_HOLE(zio->io_bp)); 839 ASSERT(zio->io_bp->blk_fill == 0); 840 841 /* 842 * Ensure the lwb buffer pointer is cleared before releasing 843 * the txg. If we have had an allocation failure and 844 * the txg is waiting to sync then we want want zil_sync() 845 * to remove the lwb so that it's not picked up as the next new 846 * one in zil_commit_writer(). zil_sync() will only remove 847 * the lwb if lwb_buf is null. 848 */ 849 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 850 mutex_enter(&zilog->zl_lock); 851 lwb->lwb_buf = NULL; 852 lwb->lwb_tx = NULL; 853 mutex_exit(&zilog->zl_lock); 854 855 /* 856 * Now that we've written this log block, we have a stable pointer 857 * to the next block in the chain, so it's OK to let the txg in 858 * which we allocated the next block sync. 859 */ 860 dmu_tx_commit(tx); 861} 862 863/* 864 * Initialize the io for a log block. 865 */ 866static void 867zil_lwb_write_init(zilog_t *zilog, lwb_t *lwb) 868{ 869 zbookmark_t zb; 870 871 SET_BOOKMARK(&zb, lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_OBJSET], 872 ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, 873 lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_SEQ]); 874 875 if (zilog->zl_root_zio == NULL) { 876 zilog->zl_root_zio = zio_root(zilog->zl_spa, NULL, NULL, 877 ZIO_FLAG_CANFAIL); 878 } 879 if (lwb->lwb_zio == NULL) { 880 lwb->lwb_zio = zio_rewrite(zilog->zl_root_zio, zilog->zl_spa, 881 0, &lwb->lwb_blk, lwb->lwb_buf, BP_GET_LSIZE(&lwb->lwb_blk), 882 zil_lwb_write_done, lwb, ZIO_PRIORITY_LOG_WRITE, 883 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE, &zb); 884 } 885} 886 887/* 888 * Define a limited set of intent log block sizes. 889 * These must be a multiple of 4KB. Note only the amount used (again 890 * aligned to 4KB) actually gets written. However, we can't always just 891 * allocate SPA_MAXBLOCKSIZE as the slog space could be exhausted. 892 */ 893uint64_t zil_block_buckets[] = { 894 4096, /* non TX_WRITE */ 895 8192+4096, /* data base */ 896 32*1024 + 4096, /* NFS writes */ 897 UINT64_MAX 898}; 899 900/* 901 * Use the slog as long as the logbias is 'latency' and the current commit size 902 * is less than the limit or the total list size is less than 2X the limit. 903 * Limit checking is disabled by setting zil_slog_limit to UINT64_MAX. 904 */ 905uint64_t zil_slog_limit = 1024 * 1024; 906#define USE_SLOG(zilog) (((zilog)->zl_logbias == ZFS_LOGBIAS_LATENCY) && \ 907 (((zilog)->zl_cur_used < zil_slog_limit) || \ 908 ((zilog)->zl_itx_list_sz < (zil_slog_limit << 1)))) 909 910/* 911 * Start a log block write and advance to the next log block. 912 * Calls are serialized. 913 */ 914static lwb_t * 915zil_lwb_write_start(zilog_t *zilog, lwb_t *lwb) 916{ 917 lwb_t *nlwb = NULL; 918 zil_chain_t *zilc; 919 spa_t *spa = zilog->zl_spa; 920 blkptr_t *bp; 921 dmu_tx_t *tx; 922 uint64_t txg; 923 uint64_t zil_blksz, wsz; 924 int i, error; 925 926 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 927 zilc = (zil_chain_t *)lwb->lwb_buf; 928 bp = &zilc->zc_next_blk; 929 } else { 930 zilc = (zil_chain_t *)(lwb->lwb_buf + lwb->lwb_sz); 931 bp = &zilc->zc_next_blk; 932 } 933 934 ASSERT(lwb->lwb_nused <= lwb->lwb_sz); 935 936 /* 937 * Allocate the next block and save its address in this block 938 * before writing it in order to establish the log chain. 939 * Note that if the allocation of nlwb synced before we wrote 940 * the block that points at it (lwb), we'd leak it if we crashed. 941 * Therefore, we don't do dmu_tx_commit() until zil_lwb_write_done(). 942 * We dirty the dataset to ensure that zil_sync() will be called 943 * to clean up in the event of allocation failure or I/O failure. 944 */ 945 tx = dmu_tx_create(zilog->zl_os); 946 VERIFY(dmu_tx_assign(tx, TXG_WAIT) == 0); 947 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 948 txg = dmu_tx_get_txg(tx); 949 950 lwb->lwb_tx = tx; 951 952 /* 953 * Log blocks are pre-allocated. Here we select the size of the next 954 * block, based on size used in the last block. 955 * - first find the smallest bucket that will fit the block from a 956 * limited set of block sizes. This is because it's faster to write 957 * blocks allocated from the same metaslab as they are adjacent or 958 * close. 959 * - next find the maximum from the new suggested size and an array of 960 * previous sizes. This lessens a picket fence effect of wrongly 961 * guesssing the size if we have a stream of say 2k, 64k, 2k, 64k 962 * requests. 963 * 964 * Note we only write what is used, but we can't just allocate 965 * the maximum block size because we can exhaust the available 966 * pool log space. 967 */ 968 zil_blksz = zilog->zl_cur_used + sizeof (zil_chain_t); 969 for (i = 0; zil_blksz > zil_block_buckets[i]; i++) 970 continue; 971 zil_blksz = zil_block_buckets[i]; 972 if (zil_blksz == UINT64_MAX) 973 zil_blksz = SPA_MAXBLOCKSIZE; 974 zilog->zl_prev_blks[zilog->zl_prev_rotor] = zil_blksz; 975 for (i = 0; i < ZIL_PREV_BLKS; i++) 976 zil_blksz = MAX(zil_blksz, zilog->zl_prev_blks[i]); 977 zilog->zl_prev_rotor = (zilog->zl_prev_rotor + 1) & (ZIL_PREV_BLKS - 1); 978 979 BP_ZERO(bp); 980 /* pass the old blkptr in order to spread log blocks across devs */ 981 error = zio_alloc_zil(spa, txg, bp, &lwb->lwb_blk, zil_blksz, 982 USE_SLOG(zilog)); 983 if (!error) { 984 ASSERT3U(bp->blk_birth, ==, txg); 985 bp->blk_cksum = lwb->lwb_blk.blk_cksum; 986 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]++; 987 988 /* 989 * Allocate a new log write buffer (lwb). 990 */ 991 nlwb = zil_alloc_lwb(zilog, bp, txg); 992 993 /* Record the block for later vdev flushing */ 994 zil_add_block(zilog, &lwb->lwb_blk); 995 } 996 997 if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { 998 /* For Slim ZIL only write what is used. */ 999 wsz = P2ROUNDUP_TYPED(lwb->lwb_nused, ZIL_MIN_BLKSZ, uint64_t); 1000 ASSERT3U(wsz, <=, lwb->lwb_sz); 1001 zio_shrink(lwb->lwb_zio, wsz); 1002 1003 } else { 1004 wsz = lwb->lwb_sz; 1005 } 1006 1007 zilc->zc_pad = 0; 1008 zilc->zc_nused = lwb->lwb_nused; 1009 zilc->zc_eck.zec_cksum = lwb->lwb_blk.blk_cksum; 1010 1011 /* 1012 * clear unused data for security 1013 */ 1014 bzero(lwb->lwb_buf + lwb->lwb_nused, wsz - lwb->lwb_nused); 1015 1016 zio_nowait(lwb->lwb_zio); /* Kick off the write for the old log block */ 1017 1018 /* 1019 * If there was an allocation failure then nlwb will be null which 1020 * forces a txg_wait_synced(). 1021 */ 1022 return (nlwb); 1023} 1024 1025static lwb_t * 1026zil_lwb_commit(zilog_t *zilog, itx_t *itx, lwb_t *lwb) 1027{ 1028 lr_t *lrc = &itx->itx_lr; /* common log record */ 1029 lr_write_t *lrw = (lr_write_t *)lrc; 1030 char *lr_buf; 1031 uint64_t txg = lrc->lrc_txg; 1032 uint64_t reclen = lrc->lrc_reclen; 1033 uint64_t dlen = 0; 1034 1035 if (lwb == NULL) 1036 return (NULL); 1037 1038 ASSERT(lwb->lwb_buf != NULL); 1039 ASSERT(zilog_is_dirty(zilog) || 1040 spa_freeze_txg(zilog->zl_spa) != UINT64_MAX); 1041 1042 if (lrc->lrc_txtype == TX_WRITE && itx->itx_wr_state == WR_NEED_COPY) 1043 dlen = P2ROUNDUP_TYPED( 1044 lrw->lr_length, sizeof (uint64_t), uint64_t); 1045 1046 zilog->zl_cur_used += (reclen + dlen); 1047 1048 zil_lwb_write_init(zilog, lwb); 1049 1050 /* 1051 * If this record won't fit in the current log block, start a new one. 1052 */ 1053 if (lwb->lwb_nused + reclen + dlen > lwb->lwb_sz) { 1054 lwb = zil_lwb_write_start(zilog, lwb); 1055 if (lwb == NULL) 1056 return (NULL); 1057 zil_lwb_write_init(zilog, lwb); 1058 ASSERT(LWB_EMPTY(lwb)); 1059 if (lwb->lwb_nused + reclen + dlen > lwb->lwb_sz) { 1060 txg_wait_synced(zilog->zl_dmu_pool, txg); 1061 return (lwb); 1062 } 1063 } 1064 1065 lr_buf = lwb->lwb_buf + lwb->lwb_nused; 1066 bcopy(lrc, lr_buf, reclen); 1067 lrc = (lr_t *)lr_buf; 1068 lrw = (lr_write_t *)lrc; 1069 1070 /* 1071 * If it's a write, fetch the data or get its blkptr as appropriate. 1072 */ 1073 if (lrc->lrc_txtype == TX_WRITE) { 1074 if (txg > spa_freeze_txg(zilog->zl_spa)) 1075 txg_wait_synced(zilog->zl_dmu_pool, txg); 1076 if (itx->itx_wr_state != WR_COPIED) { 1077 char *dbuf; 1078 int error; 1079 1080 if (dlen) { 1081 ASSERT(itx->itx_wr_state == WR_NEED_COPY); 1082 dbuf = lr_buf + reclen; 1083 lrw->lr_common.lrc_reclen += dlen; 1084 } else { 1085 ASSERT(itx->itx_wr_state == WR_INDIRECT); 1086 dbuf = NULL; 1087 } 1088 error = zilog->zl_get_data( 1089 itx->itx_private, lrw, dbuf, lwb->lwb_zio); 1090 if (error == EIO) { 1091 txg_wait_synced(zilog->zl_dmu_pool, txg); 1092 return (lwb); 1093 } 1094 if (error) { 1095 ASSERT(error == ENOENT || error == EEXIST || 1096 error == EALREADY); 1097 return (lwb); 1098 } 1099 } 1100 } 1101 1102 /* 1103 * We're actually making an entry, so update lrc_seq to be the 1104 * log record sequence number. Note that this is generally not 1105 * equal to the itx sequence number because not all transactions 1106 * are synchronous, and sometimes spa_sync() gets there first. 1107 */ 1108 lrc->lrc_seq = ++zilog->zl_lr_seq; /* we are single threaded */ 1109 lwb->lwb_nused += reclen + dlen; 1110 lwb->lwb_max_txg = MAX(lwb->lwb_max_txg, txg); 1111 ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_sz); 1112 ASSERT0(P2PHASE(lwb->lwb_nused, sizeof (uint64_t))); 1113 1114 return (lwb); 1115} 1116 1117itx_t * 1118zil_itx_create(uint64_t txtype, size_t lrsize) 1119{ 1120 itx_t *itx; 1121 1122 lrsize = P2ROUNDUP_TYPED(lrsize, sizeof (uint64_t), size_t); 1123 1124 itx = kmem_alloc(offsetof(itx_t, itx_lr) + lrsize, KM_SLEEP); 1125 itx->itx_lr.lrc_txtype = txtype; 1126 itx->itx_lr.lrc_reclen = lrsize; 1127 itx->itx_sod = lrsize; /* if write & WR_NEED_COPY will be increased */ 1128 itx->itx_lr.lrc_seq = 0; /* defensive */ 1129 itx->itx_sync = B_TRUE; /* default is synchronous */ 1130 1131 return (itx); 1132} 1133 1134void 1135zil_itx_destroy(itx_t *itx) 1136{ 1137 kmem_free(itx, offsetof(itx_t, itx_lr) + itx->itx_lr.lrc_reclen); 1138} 1139 1140/* 1141 * Free up the sync and async itxs. The itxs_t has already been detached 1142 * so no locks are needed. 1143 */ 1144static void 1145zil_itxg_clean(itxs_t *itxs) 1146{ 1147 itx_t *itx; 1148 list_t *list; 1149 avl_tree_t *t; 1150 void *cookie; 1151 itx_async_node_t *ian; 1152 1153 list = &itxs->i_sync_list; 1154 while ((itx = list_head(list)) != NULL) { 1155 list_remove(list, itx); 1156 kmem_free(itx, offsetof(itx_t, itx_lr) + 1157 itx->itx_lr.lrc_reclen); 1158 } 1159 1160 cookie = NULL; 1161 t = &itxs->i_async_tree; 1162 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1163 list = &ian->ia_list; 1164 while ((itx = list_head(list)) != NULL) { 1165 list_remove(list, itx); 1166 kmem_free(itx, offsetof(itx_t, itx_lr) + 1167 itx->itx_lr.lrc_reclen); 1168 } 1169 list_destroy(list); 1170 kmem_free(ian, sizeof (itx_async_node_t)); 1171 } 1172 avl_destroy(t); 1173 1174 kmem_free(itxs, sizeof (itxs_t)); 1175} 1176 1177static int 1178zil_aitx_compare(const void *x1, const void *x2) 1179{ 1180 const uint64_t o1 = ((itx_async_node_t *)x1)->ia_foid; 1181 const uint64_t o2 = ((itx_async_node_t *)x2)->ia_foid; 1182 1183 if (o1 < o2) 1184 return (-1); 1185 if (o1 > o2) 1186 return (1); 1187 1188 return (0); 1189} 1190 1191/* 1192 * Remove all async itx with the given oid. 1193 */ 1194static void 1195zil_remove_async(zilog_t *zilog, uint64_t oid) 1196{ 1197 uint64_t otxg, txg; 1198 itx_async_node_t *ian; 1199 avl_tree_t *t; 1200 avl_index_t where; 1201 list_t clean_list; 1202 itx_t *itx; 1203 1204 ASSERT(oid != 0); 1205 list_create(&clean_list, sizeof (itx_t), offsetof(itx_t, itx_node)); 1206 1207 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1208 otxg = ZILTEST_TXG; 1209 else 1210 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1211 1212 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1213 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1214 1215 mutex_enter(&itxg->itxg_lock); 1216 if (itxg->itxg_txg != txg) { 1217 mutex_exit(&itxg->itxg_lock); 1218 continue; 1219 } 1220 1221 /* 1222 * Locate the object node and append its list. 1223 */ 1224 t = &itxg->itxg_itxs->i_async_tree; 1225 ian = avl_find(t, &oid, &where); 1226 if (ian != NULL) 1227 list_move_tail(&clean_list, &ian->ia_list); 1228 mutex_exit(&itxg->itxg_lock); 1229 } 1230 while ((itx = list_head(&clean_list)) != NULL) { 1231 list_remove(&clean_list, itx); 1232 kmem_free(itx, offsetof(itx_t, itx_lr) + 1233 itx->itx_lr.lrc_reclen); 1234 } 1235 list_destroy(&clean_list); 1236} 1237 1238void 1239zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx) 1240{ 1241 uint64_t txg; 1242 itxg_t *itxg; 1243 itxs_t *itxs, *clean = NULL; 1244 1245 /* 1246 * Object ids can be re-instantiated in the next txg so 1247 * remove any async transactions to avoid future leaks. 1248 * This can happen if a fsync occurs on the re-instantiated 1249 * object for a WR_INDIRECT or WR_NEED_COPY write, which gets 1250 * the new file data and flushes a write record for the old object. 1251 */ 1252 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_REMOVE) 1253 zil_remove_async(zilog, itx->itx_oid); 1254 1255 /* 1256 * Ensure the data of a renamed file is committed before the rename. 1257 */ 1258 if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_RENAME) 1259 zil_async_to_sync(zilog, itx->itx_oid); 1260 1261 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) 1262 txg = ZILTEST_TXG; 1263 else 1264 txg = dmu_tx_get_txg(tx); 1265 1266 itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1267 mutex_enter(&itxg->itxg_lock); 1268 itxs = itxg->itxg_itxs; 1269 if (itxg->itxg_txg != txg) { 1270 if (itxs != NULL) { 1271 /* 1272 * The zil_clean callback hasn't got around to cleaning 1273 * this itxg. Save the itxs for release below. 1274 * This should be rare. 1275 */ 1276 atomic_add_64(&zilog->zl_itx_list_sz, -itxg->itxg_sod); 1277 itxg->itxg_sod = 0; 1278 clean = itxg->itxg_itxs; 1279 } 1280 ASSERT(itxg->itxg_sod == 0); 1281 itxg->itxg_txg = txg; 1282 itxs = itxg->itxg_itxs = kmem_zalloc(sizeof (itxs_t), KM_SLEEP); 1283 1284 list_create(&itxs->i_sync_list, sizeof (itx_t), 1285 offsetof(itx_t, itx_node)); 1286 avl_create(&itxs->i_async_tree, zil_aitx_compare, 1287 sizeof (itx_async_node_t), 1288 offsetof(itx_async_node_t, ia_node)); 1289 } 1290 if (itx->itx_sync) { 1291 list_insert_tail(&itxs->i_sync_list, itx); 1292 atomic_add_64(&zilog->zl_itx_list_sz, itx->itx_sod); 1293 itxg->itxg_sod += itx->itx_sod; 1294 } else { 1295 avl_tree_t *t = &itxs->i_async_tree; 1296 uint64_t foid = ((lr_ooo_t *)&itx->itx_lr)->lr_foid; 1297 itx_async_node_t *ian; 1298 avl_index_t where; 1299 1300 ian = avl_find(t, &foid, &where); 1301 if (ian == NULL) { 1302 ian = kmem_alloc(sizeof (itx_async_node_t), KM_SLEEP); 1303 list_create(&ian->ia_list, sizeof (itx_t), 1304 offsetof(itx_t, itx_node)); 1305 ian->ia_foid = foid; 1306 avl_insert(t, ian, where); 1307 } 1308 list_insert_tail(&ian->ia_list, itx); 1309 } 1310 1311 itx->itx_lr.lrc_txg = dmu_tx_get_txg(tx); 1312 zilog_dirty(zilog, txg); 1313 mutex_exit(&itxg->itxg_lock); 1314 1315 /* Release the old itxs now we've dropped the lock */ 1316 if (clean != NULL) 1317 zil_itxg_clean(clean); 1318} 1319 1320/* 1321 * If there are any in-memory intent log transactions which have now been 1322 * synced then start up a taskq to free them. We should only do this after we 1323 * have written out the uberblocks (i.e. txg has been comitted) so that 1324 * don't inadvertently clean out in-memory log records that would be required 1325 * by zil_commit(). 1326 */ 1327void 1328zil_clean(zilog_t *zilog, uint64_t synced_txg) 1329{ 1330 itxg_t *itxg = &zilog->zl_itxg[synced_txg & TXG_MASK]; 1331 itxs_t *clean_me; 1332 1333 mutex_enter(&itxg->itxg_lock); 1334 if (itxg->itxg_itxs == NULL || itxg->itxg_txg == ZILTEST_TXG) { 1335 mutex_exit(&itxg->itxg_lock); 1336 return; 1337 } 1338 ASSERT3U(itxg->itxg_txg, <=, synced_txg); 1339 ASSERT(itxg->itxg_txg != 0); 1340 ASSERT(zilog->zl_clean_taskq != NULL); 1341 atomic_add_64(&zilog->zl_itx_list_sz, -itxg->itxg_sod); 1342 itxg->itxg_sod = 0; 1343 clean_me = itxg->itxg_itxs; 1344 itxg->itxg_itxs = NULL; 1345 itxg->itxg_txg = 0; 1346 mutex_exit(&itxg->itxg_lock); 1347 /* 1348 * Preferably start a task queue to free up the old itxs but 1349 * if taskq_dispatch can't allocate resources to do that then 1350 * free it in-line. This should be rare. Note, using TQ_SLEEP 1351 * created a bad performance problem. 1352 */ 1353 if (taskq_dispatch(zilog->zl_clean_taskq, 1354 (void (*)(void *))zil_itxg_clean, clean_me, TQ_NOSLEEP) == 0) 1355 zil_itxg_clean(clean_me); 1356} 1357 1358/* 1359 * Get the list of itxs to commit into zl_itx_commit_list. 1360 */ 1361static void 1362zil_get_commit_list(zilog_t *zilog) 1363{ 1364 uint64_t otxg, txg; 1365 list_t *commit_list = &zilog->zl_itx_commit_list; 1366 uint64_t push_sod = 0; 1367 1368 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1369 otxg = ZILTEST_TXG; 1370 else 1371 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1372 1373 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1374 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1375 1376 mutex_enter(&itxg->itxg_lock); 1377 if (itxg->itxg_txg != txg) { 1378 mutex_exit(&itxg->itxg_lock); 1379 continue; 1380 } 1381 1382 list_move_tail(commit_list, &itxg->itxg_itxs->i_sync_list); 1383 push_sod += itxg->itxg_sod; 1384 itxg->itxg_sod = 0; 1385 1386 mutex_exit(&itxg->itxg_lock); 1387 } 1388 atomic_add_64(&zilog->zl_itx_list_sz, -push_sod); 1389} 1390 1391/* 1392 * Move the async itxs for a specified object to commit into sync lists. 1393 */ 1394static void 1395zil_async_to_sync(zilog_t *zilog, uint64_t foid) 1396{ 1397 uint64_t otxg, txg; 1398 itx_async_node_t *ian; 1399 avl_tree_t *t; 1400 avl_index_t where; 1401 1402 if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ 1403 otxg = ZILTEST_TXG; 1404 else 1405 otxg = spa_last_synced_txg(zilog->zl_spa) + 1; 1406 1407 for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { 1408 itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; 1409 1410 mutex_enter(&itxg->itxg_lock); 1411 if (itxg->itxg_txg != txg) { 1412 mutex_exit(&itxg->itxg_lock); 1413 continue; 1414 } 1415 1416 /* 1417 * If a foid is specified then find that node and append its 1418 * list. Otherwise walk the tree appending all the lists 1419 * to the sync list. We add to the end rather than the 1420 * beginning to ensure the create has happened. 1421 */ 1422 t = &itxg->itxg_itxs->i_async_tree; 1423 if (foid != 0) { 1424 ian = avl_find(t, &foid, &where); 1425 if (ian != NULL) { 1426 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1427 &ian->ia_list); 1428 } 1429 } else { 1430 void *cookie = NULL; 1431 1432 while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { 1433 list_move_tail(&itxg->itxg_itxs->i_sync_list, 1434 &ian->ia_list); 1435 list_destroy(&ian->ia_list); 1436 kmem_free(ian, sizeof (itx_async_node_t)); 1437 } 1438 } 1439 mutex_exit(&itxg->itxg_lock); 1440 } 1441} 1442 1443static void 1444zil_commit_writer(zilog_t *zilog) 1445{ 1446 uint64_t txg; 1447 itx_t *itx; 1448 lwb_t *lwb; 1449 spa_t *spa = zilog->zl_spa; 1450 int error = 0; 1451 1452 ASSERT(zilog->zl_root_zio == NULL); 1453 1454 mutex_exit(&zilog->zl_lock); 1455 1456 zil_get_commit_list(zilog); 1457 1458 /* 1459 * Return if there's nothing to commit before we dirty the fs by 1460 * calling zil_create(). 1461 */ 1462 if (list_head(&zilog->zl_itx_commit_list) == NULL) { 1463 mutex_enter(&zilog->zl_lock); 1464 return; 1465 } 1466 1467 if (zilog->zl_suspend) { 1468 lwb = NULL; 1469 } else { 1470 lwb = list_tail(&zilog->zl_lwb_list); 1471 if (lwb == NULL) 1472 lwb = zil_create(zilog); 1473 } 1474 1475 DTRACE_PROBE1(zil__cw1, zilog_t *, zilog); 1476 while (itx = list_head(&zilog->zl_itx_commit_list)) { 1477 txg = itx->itx_lr.lrc_txg; 1478 ASSERT(txg); 1479 1480 if (txg > spa_last_synced_txg(spa) || txg > spa_freeze_txg(spa)) 1481 lwb = zil_lwb_commit(zilog, itx, lwb); 1482 list_remove(&zilog->zl_itx_commit_list, itx); 1483 kmem_free(itx, offsetof(itx_t, itx_lr) 1484 + itx->itx_lr.lrc_reclen); 1485 } 1486 DTRACE_PROBE1(zil__cw2, zilog_t *, zilog); 1487 1488 /* write the last block out */ 1489 if (lwb != NULL && lwb->lwb_zio != NULL) 1490 lwb = zil_lwb_write_start(zilog, lwb); 1491 1492 zilog->zl_cur_used = 0; 1493 1494 /* 1495 * Wait if necessary for the log blocks to be on stable storage. 1496 */ 1497 if (zilog->zl_root_zio) { 1498 error = zio_wait(zilog->zl_root_zio); 1499 zilog->zl_root_zio = NULL; 1500 zil_flush_vdevs(zilog); 1501 } 1502 1503 if (error || lwb == NULL) 1504 txg_wait_synced(zilog->zl_dmu_pool, 0); 1505 1506 mutex_enter(&zilog->zl_lock); 1507 1508 /* 1509 * Remember the highest committed log sequence number for ztest. 1510 * We only update this value when all the log writes succeeded, 1511 * because ztest wants to ASSERT that it got the whole log chain. 1512 */ 1513 if (error == 0 && lwb != NULL) 1514 zilog->zl_commit_lr_seq = zilog->zl_lr_seq; 1515} 1516 1517/* 1518 * Commit zfs transactions to stable storage. 1519 * If foid is 0 push out all transactions, otherwise push only those 1520 * for that object or might reference that object. 1521 * 1522 * itxs are committed in batches. In a heavily stressed zil there will be 1523 * a commit writer thread who is writing out a bunch of itxs to the log 1524 * for a set of committing threads (cthreads) in the same batch as the writer. 1525 * Those cthreads are all waiting on the same cv for that batch. 1526 * 1527 * There will also be a different and growing batch of threads that are 1528 * waiting to commit (qthreads). When the committing batch completes 1529 * a transition occurs such that the cthreads exit and the qthreads become 1530 * cthreads. One of the new cthreads becomes the writer thread for the 1531 * batch. Any new threads arriving become new qthreads. 1532 * 1533 * Only 2 condition variables are needed and there's no transition 1534 * between the two cvs needed. They just flip-flop between qthreads 1535 * and cthreads. 1536 * 1537 * Using this scheme we can efficiently wakeup up only those threads 1538 * that have been committed. 1539 */ 1540void 1541zil_commit(zilog_t *zilog, uint64_t foid) 1542{ 1543 uint64_t mybatch; 1544 1545 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 1546 return; 1547 1548 /* move the async itxs for the foid to the sync queues */ 1549 zil_async_to_sync(zilog, foid); 1550 1551 mutex_enter(&zilog->zl_lock); 1552 mybatch = zilog->zl_next_batch; 1553 while (zilog->zl_writer) { 1554 cv_wait(&zilog->zl_cv_batch[mybatch & 1], &zilog->zl_lock); 1555 if (mybatch <= zilog->zl_com_batch) { 1556 mutex_exit(&zilog->zl_lock); 1557 return; 1558 } 1559 } 1560 1561 zilog->zl_next_batch++; 1562 zilog->zl_writer = B_TRUE; 1563 zil_commit_writer(zilog); 1564 zilog->zl_com_batch = mybatch; 1565 zilog->zl_writer = B_FALSE; 1566 mutex_exit(&zilog->zl_lock); 1567 1568 /* wake up one thread to become the next writer */ 1569 cv_signal(&zilog->zl_cv_batch[(mybatch+1) & 1]); 1570 1571 /* wake up all threads waiting for this batch to be committed */ 1572 cv_broadcast(&zilog->zl_cv_batch[mybatch & 1]); 1573} 1574 1575/* 1576 * Called in syncing context to free committed log blocks and update log header. 1577 */ 1578void 1579zil_sync(zilog_t *zilog, dmu_tx_t *tx) 1580{ 1581 zil_header_t *zh = zil_header_in_syncing_context(zilog); 1582 uint64_t txg = dmu_tx_get_txg(tx); 1583 spa_t *spa = zilog->zl_spa; 1584 uint64_t *replayed_seq = &zilog->zl_replayed_seq[txg & TXG_MASK]; 1585 lwb_t *lwb; 1586 1587 /* 1588 * We don't zero out zl_destroy_txg, so make sure we don't try 1589 * to destroy it twice. 1590 */ 1591 if (spa_sync_pass(spa) != 1) 1592 return; 1593 1594 mutex_enter(&zilog->zl_lock); 1595 1596 ASSERT(zilog->zl_stop_sync == 0); 1597 1598 if (*replayed_seq != 0) { 1599 ASSERT(zh->zh_replay_seq < *replayed_seq); 1600 zh->zh_replay_seq = *replayed_seq; 1601 *replayed_seq = 0; 1602 } 1603 1604 if (zilog->zl_destroy_txg == txg) { 1605 blkptr_t blk = zh->zh_log; 1606 1607 ASSERT(list_head(&zilog->zl_lwb_list) == NULL); 1608 1609 bzero(zh, sizeof (zil_header_t)); 1610 bzero(zilog->zl_replayed_seq, sizeof (zilog->zl_replayed_seq)); 1611 1612 if (zilog->zl_keep_first) { 1613 /* 1614 * If this block was part of log chain that couldn't 1615 * be claimed because a device was missing during 1616 * zil_claim(), but that device later returns, 1617 * then this block could erroneously appear valid. 1618 * To guard against this, assign a new GUID to the new 1619 * log chain so it doesn't matter what blk points to. 1620 */ 1621 zil_init_log_chain(zilog, &blk); 1622 zh->zh_log = blk; 1623 } 1624 } 1625 1626 while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { 1627 zh->zh_log = lwb->lwb_blk; 1628 if (lwb->lwb_buf != NULL || lwb->lwb_max_txg > txg) 1629 break; 1630 list_remove(&zilog->zl_lwb_list, lwb); 1631 zio_free_zil(spa, txg, &lwb->lwb_blk); 1632 kmem_cache_free(zil_lwb_cache, lwb); 1633 1634 /* 1635 * If we don't have anything left in the lwb list then 1636 * we've had an allocation failure and we need to zero 1637 * out the zil_header blkptr so that we don't end 1638 * up freeing the same block twice. 1639 */ 1640 if (list_head(&zilog->zl_lwb_list) == NULL) 1641 BP_ZERO(&zh->zh_log); 1642 } 1643 mutex_exit(&zilog->zl_lock); 1644} 1645 1646void 1647zil_init(void) 1648{ 1649 zil_lwb_cache = kmem_cache_create("zil_lwb_cache", 1650 sizeof (struct lwb), 0, NULL, NULL, NULL, NULL, NULL, 0); 1651} 1652 1653void 1654zil_fini(void) 1655{ 1656 kmem_cache_destroy(zil_lwb_cache); 1657} 1658 1659void 1660zil_set_sync(zilog_t *zilog, uint64_t sync) 1661{ 1662 zilog->zl_sync = sync; 1663} 1664 1665void 1666zil_set_logbias(zilog_t *zilog, uint64_t logbias) 1667{ 1668 zilog->zl_logbias = logbias; 1669} 1670 1671zilog_t * 1672zil_alloc(objset_t *os, zil_header_t *zh_phys) 1673{ 1674 zilog_t *zilog; 1675 1676 zilog = kmem_zalloc(sizeof (zilog_t), KM_SLEEP); 1677 1678 zilog->zl_header = zh_phys; 1679 zilog->zl_os = os; 1680 zilog->zl_spa = dmu_objset_spa(os); 1681 zilog->zl_dmu_pool = dmu_objset_pool(os); 1682 zilog->zl_destroy_txg = TXG_INITIAL - 1; 1683 zilog->zl_logbias = dmu_objset_logbias(os); 1684 zilog->zl_sync = dmu_objset_syncprop(os); 1685 zilog->zl_next_batch = 1; 1686 1687 mutex_init(&zilog->zl_lock, NULL, MUTEX_DEFAULT, NULL); 1688 1689 for (int i = 0; i < TXG_SIZE; i++) { 1690 mutex_init(&zilog->zl_itxg[i].itxg_lock, NULL, 1691 MUTEX_DEFAULT, NULL); 1692 } 1693 1694 list_create(&zilog->zl_lwb_list, sizeof (lwb_t), 1695 offsetof(lwb_t, lwb_node)); 1696 1697 list_create(&zilog->zl_itx_commit_list, sizeof (itx_t), 1698 offsetof(itx_t, itx_node)); 1699 1700 mutex_init(&zilog->zl_vdev_lock, NULL, MUTEX_DEFAULT, NULL); 1701 1702 avl_create(&zilog->zl_vdev_tree, zil_vdev_compare, 1703 sizeof (zil_vdev_node_t), offsetof(zil_vdev_node_t, zv_node)); 1704 1705 cv_init(&zilog->zl_cv_writer, NULL, CV_DEFAULT, NULL); 1706 cv_init(&zilog->zl_cv_suspend, NULL, CV_DEFAULT, NULL); 1707 cv_init(&zilog->zl_cv_batch[0], NULL, CV_DEFAULT, NULL); 1708 cv_init(&zilog->zl_cv_batch[1], NULL, CV_DEFAULT, NULL); 1709 1710 return (zilog); 1711} 1712 1713void 1714zil_free(zilog_t *zilog) 1715{ 1716 zilog->zl_stop_sync = 1; 1717 1718 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1719 list_destroy(&zilog->zl_lwb_list); 1720 1721 avl_destroy(&zilog->zl_vdev_tree); 1722 mutex_destroy(&zilog->zl_vdev_lock); 1723 1724 ASSERT(list_is_empty(&zilog->zl_itx_commit_list)); 1725 list_destroy(&zilog->zl_itx_commit_list); 1726 1727 for (int i = 0; i < TXG_SIZE; i++) { 1728 /* 1729 * It's possible for an itx to be generated that doesn't dirty 1730 * a txg (e.g. ztest TX_TRUNCATE). So there's no zil_clean() 1731 * callback to remove the entry. We remove those here. 1732 * 1733 * Also free up the ziltest itxs. 1734 */ 1735 if (zilog->zl_itxg[i].itxg_itxs) 1736 zil_itxg_clean(zilog->zl_itxg[i].itxg_itxs); 1737 mutex_destroy(&zilog->zl_itxg[i].itxg_lock); 1738 } 1739 1740 mutex_destroy(&zilog->zl_lock); 1741 1742 cv_destroy(&zilog->zl_cv_writer); 1743 cv_destroy(&zilog->zl_cv_suspend); 1744 cv_destroy(&zilog->zl_cv_batch[0]); 1745 cv_destroy(&zilog->zl_cv_batch[1]); 1746 1747 kmem_free(zilog, sizeof (zilog_t)); 1748} 1749 1750/* 1751 * Open an intent log. 1752 */ 1753zilog_t * 1754zil_open(objset_t *os, zil_get_data_t *get_data) 1755{ 1756 zilog_t *zilog = dmu_objset_zil(os); 1757 1758 ASSERT(zilog->zl_clean_taskq == NULL); 1759 ASSERT(zilog->zl_get_data == NULL); 1760 ASSERT(list_is_empty(&zilog->zl_lwb_list)); 1761 1762 zilog->zl_get_data = get_data; 1763 zilog->zl_clean_taskq = taskq_create("zil_clean", 1, minclsyspri, 1764 2, 2, TASKQ_PREPOPULATE); 1765 1766 return (zilog); 1767} 1768 1769/* 1770 * Close an intent log. 1771 */ 1772void 1773zil_close(zilog_t *zilog) 1774{ 1775 lwb_t *lwb; 1776 uint64_t txg = 0; 1777 1778 zil_commit(zilog, 0); /* commit all itx */ 1779 1780 /* 1781 * The lwb_max_txg for the stubby lwb will reflect the last activity 1782 * for the zil. After a txg_wait_synced() on the txg we know all the 1783 * callbacks have occurred that may clean the zil. Only then can we 1784 * destroy the zl_clean_taskq. 1785 */ 1786 mutex_enter(&zilog->zl_lock); 1787 lwb = list_tail(&zilog->zl_lwb_list); 1788 if (lwb != NULL) 1789 txg = lwb->lwb_max_txg; 1790 mutex_exit(&zilog->zl_lock); 1791 if (txg) 1792 txg_wait_synced(zilog->zl_dmu_pool, txg); 1793 ASSERT(!zilog_is_dirty(zilog)); 1794 1795 taskq_destroy(zilog->zl_clean_taskq); 1796 zilog->zl_clean_taskq = NULL; 1797 zilog->zl_get_data = NULL; 1798 1799 /* 1800 * We should have only one LWB left on the list; remove it now. 1801 */ 1802 mutex_enter(&zilog->zl_lock); 1803 lwb = list_head(&zilog->zl_lwb_list); 1804 if (lwb != NULL) { 1805 ASSERT(lwb == list_tail(&zilog->zl_lwb_list)); 1806 list_remove(&zilog->zl_lwb_list, lwb); 1807 zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); 1808 kmem_cache_free(zil_lwb_cache, lwb); 1809 } 1810 mutex_exit(&zilog->zl_lock); 1811} 1812 1813/* 1814 * Suspend an intent log. While in suspended mode, we still honor 1815 * synchronous semantics, but we rely on txg_wait_synced() to do it. 1816 * We suspend the log briefly when taking a snapshot so that the snapshot 1817 * contains all the data it's supposed to, and has an empty intent log. 1818 */ 1819int 1820zil_suspend(zilog_t *zilog) 1821{ 1822 const zil_header_t *zh = zilog->zl_header; 1823 1824 mutex_enter(&zilog->zl_lock); 1825 if (zh->zh_flags & ZIL_REPLAY_NEEDED) { /* unplayed log */ 1826 mutex_exit(&zilog->zl_lock); 1827 return (EBUSY); 1828 } 1829 if (zilog->zl_suspend++ != 0) { 1830 /* 1831 * Someone else already began a suspend. 1832 * Just wait for them to finish. 1833 */ 1834 while (zilog->zl_suspending) 1835 cv_wait(&zilog->zl_cv_suspend, &zilog->zl_lock); 1836 mutex_exit(&zilog->zl_lock); 1837 return (0); 1838 } 1839 zilog->zl_suspending = B_TRUE; 1840 mutex_exit(&zilog->zl_lock); 1841 1842 zil_commit(zilog, 0); 1843 1844 zil_destroy(zilog, B_FALSE); 1845 1846 mutex_enter(&zilog->zl_lock); 1847 zilog->zl_suspending = B_FALSE; 1848 cv_broadcast(&zilog->zl_cv_suspend); 1849 mutex_exit(&zilog->zl_lock); 1850 1851 return (0); 1852} 1853 1854void 1855zil_resume(zilog_t *zilog) 1856{ 1857 mutex_enter(&zilog->zl_lock); 1858 ASSERT(zilog->zl_suspend != 0); 1859 zilog->zl_suspend--; 1860 mutex_exit(&zilog->zl_lock); 1861} 1862 1863typedef struct zil_replay_arg { 1864 zil_replay_func_t **zr_replay; 1865 void *zr_arg; 1866 boolean_t zr_byteswap; 1867 char *zr_lr; 1868} zil_replay_arg_t; 1869 1870static int 1871zil_replay_error(zilog_t *zilog, lr_t *lr, int error) 1872{ 1873 char name[MAXNAMELEN]; 1874 1875 zilog->zl_replaying_seq--; /* didn't actually replay this one */ 1876 1877 dmu_objset_name(zilog->zl_os, name); 1878 1879 cmn_err(CE_WARN, "ZFS replay transaction error %d, " 1880 "dataset %s, seq 0x%llx, txtype %llu %s\n", error, name, 1881 (u_longlong_t)lr->lrc_seq, 1882 (u_longlong_t)(lr->lrc_txtype & ~TX_CI), 1883 (lr->lrc_txtype & TX_CI) ? "CI" : ""); 1884 1885 return (error); 1886} 1887 1888static int 1889zil_replay_log_record(zilog_t *zilog, lr_t *lr, void *zra, uint64_t claim_txg) 1890{ 1891 zil_replay_arg_t *zr = zra; 1892 const zil_header_t *zh = zilog->zl_header; 1893 uint64_t reclen = lr->lrc_reclen; 1894 uint64_t txtype = lr->lrc_txtype; 1895 int error = 0; 1896 1897 zilog->zl_replaying_seq = lr->lrc_seq; 1898 1899 if (lr->lrc_seq <= zh->zh_replay_seq) /* already replayed */ 1900 return (0); 1901 1902 if (lr->lrc_txg < claim_txg) /* already committed */ 1903 return (0); 1904 1905 /* Strip case-insensitive bit, still present in log record */ 1906 txtype &= ~TX_CI; 1907 1908 if (txtype == 0 || txtype >= TX_MAX_TYPE) 1909 return (zil_replay_error(zilog, lr, EINVAL)); 1910 1911 /* 1912 * If this record type can be logged out of order, the object 1913 * (lr_foid) may no longer exist. That's legitimate, not an error. 1914 */ 1915 if (TX_OOO(txtype)) { 1916 error = dmu_object_info(zilog->zl_os, 1917 ((lr_ooo_t *)lr)->lr_foid, NULL); 1918 if (error == ENOENT || error == EEXIST) 1919 return (0); 1920 } 1921 1922 /* 1923 * Make a copy of the data so we can revise and extend it. 1924 */ 1925 bcopy(lr, zr->zr_lr, reclen); 1926 1927 /* 1928 * If this is a TX_WRITE with a blkptr, suck in the data. 1929 */ 1930 if (txtype == TX_WRITE && reclen == sizeof (lr_write_t)) { 1931 error = zil_read_log_data(zilog, (lr_write_t *)lr, 1932 zr->zr_lr + reclen); 1933 if (error) 1934 return (zil_replay_error(zilog, lr, error)); 1935 } 1936 1937 /* 1938 * The log block containing this lr may have been byteswapped 1939 * so that we can easily examine common fields like lrc_txtype. 1940 * However, the log is a mix of different record types, and only the 1941 * replay vectors know how to byteswap their records. Therefore, if 1942 * the lr was byteswapped, undo it before invoking the replay vector. 1943 */ 1944 if (zr->zr_byteswap) 1945 byteswap_uint64_array(zr->zr_lr, reclen); 1946 1947 /* 1948 * We must now do two things atomically: replay this log record, 1949 * and update the log header sequence number to reflect the fact that 1950 * we did so. At the end of each replay function the sequence number 1951 * is updated if we are in replay mode. 1952 */ 1953 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, zr->zr_byteswap); 1954 if (error) { 1955 /* 1956 * The DMU's dnode layer doesn't see removes until the txg 1957 * commits, so a subsequent claim can spuriously fail with 1958 * EEXIST. So if we receive any error we try syncing out 1959 * any removes then retry the transaction. Note that we 1960 * specify B_FALSE for byteswap now, so we don't do it twice. 1961 */ 1962 txg_wait_synced(spa_get_dsl(zilog->zl_spa), 0); 1963 error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, B_FALSE); 1964 if (error) 1965 return (zil_replay_error(zilog, lr, error)); 1966 } 1967 return (0); 1968} 1969 1970/* ARGSUSED */ 1971static int 1972zil_incr_blks(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 1973{ 1974 zilog->zl_replay_blks++; 1975 1976 return (0); 1977} 1978 1979/* 1980 * If this dataset has a non-empty intent log, replay it and destroy it. 1981 */ 1982void 1983zil_replay(objset_t *os, void *arg, zil_replay_func_t *replay_func[TX_MAX_TYPE]) 1984{ 1985 zilog_t *zilog = dmu_objset_zil(os); 1986 const zil_header_t *zh = zilog->zl_header; 1987 zil_replay_arg_t zr; 1988 1989 if ((zh->zh_flags & ZIL_REPLAY_NEEDED) == 0) { 1990 zil_destroy(zilog, B_TRUE); 1991 return; 1992 } 1993 //printf("ZFS: Replaying ZIL on %s...\n", os->os->os_spa->spa_name); 1994 1995 zr.zr_replay = replay_func; 1996 zr.zr_arg = arg; 1997 zr.zr_byteswap = BP_SHOULD_BYTESWAP(&zh->zh_log); 1998 zr.zr_lr = kmem_alloc(2 * SPA_MAXBLOCKSIZE, KM_SLEEP); 1999 2000 /* 2001 * Wait for in-progress removes to sync before starting replay. 2002 */ 2003 txg_wait_synced(zilog->zl_dmu_pool, 0); 2004 2005 zilog->zl_replay = B_TRUE; 2006 zilog->zl_replay_time = ddi_get_lbolt(); 2007 ASSERT(zilog->zl_replay_blks == 0); 2008 (void) zil_parse(zilog, zil_incr_blks, zil_replay_log_record, &zr, 2009 zh->zh_claim_txg); 2010 kmem_free(zr.zr_lr, 2 * SPA_MAXBLOCKSIZE); 2011 2012 zil_destroy(zilog, B_FALSE); 2013 txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); 2014 zilog->zl_replay = B_FALSE; 2015 //printf("ZFS: Replay of ZIL on %s finished.\n", os->os->os_spa->spa_name); 2016} 2017 2018boolean_t 2019zil_replaying(zilog_t *zilog, dmu_tx_t *tx) 2020{ 2021 if (zilog->zl_sync == ZFS_SYNC_DISABLED) 2022 return (B_TRUE); 2023 2024 if (zilog->zl_replay) { 2025 dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); 2026 zilog->zl_replayed_seq[dmu_tx_get_txg(tx) & TXG_MASK] = 2027 zilog->zl_replaying_seq; 2028 return (B_TRUE); 2029 } 2030 2031 return (B_FALSE); 2032} 2033 2034/* ARGSUSED */ 2035int 2036zil_vdev_offline(const char *osname, void *arg) 2037{ 2038 objset_t *os; 2039 zilog_t *zilog; 2040 int error; 2041 2042 error = dmu_objset_hold(osname, FTAG, &os); 2043 if (error) 2044 return (error); 2045 2046 zilog = dmu_objset_zil(os); 2047 if (zil_suspend(zilog) != 0) 2048 error = EEXIST; 2049 else 2050 zil_resume(zilog); 2051 dmu_objset_rele(os, FTAG); 2052 return (error); 2053} 2054