| /* |
| * CDDL HEADER START |
| * |
| * The contents of this file are subject to the terms of the |
| * Common Development and Distribution License (the "License"). |
| * You may not use this file except in compliance with the License. |
| * |
| * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE |
| * or http://www.opensolaris.org/os/licensing. |
| * See the License for the specific language governing permissions |
| * and limitations under the License. |
| * |
| * When distributing Covered Code, include this CDDL HEADER in each |
| * file and include the License file at usr/src/OPENSOLARIS.LICENSE. |
| * If applicable, add the following below this CDDL HEADER, with the |
| * fields enclosed by brackets "[]" replaced with your own identifying |
| * information: Portions Copyright [yyyy] [name of copyright owner] |
| * |
| * CDDL HEADER END |
| */ |
| /* |
| * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. |
| * Copyright (c) 2011, 2018 by Delphix. All rights reserved. |
| * Copyright (c) 2014 Integros [integros.com] |
| * Copyright (c) 2018 Datto Inc. |
| */ |
| |
| /* Portions Copyright 2010 Robert Milkowski */ |
| |
| #include <sys/zfs_context.h> |
| #include <sys/spa.h> |
| #include <sys/spa_impl.h> |
| #include <sys/dmu.h> |
| #include <sys/zap.h> |
| #include <sys/arc.h> |
| #include <sys/stat.h> |
| #include <sys/zil.h> |
| #include <sys/zil_impl.h> |
| #include <sys/dsl_dataset.h> |
| #include <sys/vdev_impl.h> |
| #include <sys/dmu_tx.h> |
| #include <sys/dsl_pool.h> |
| #include <sys/metaslab.h> |
| #include <sys/trace_zil.h> |
| #include <sys/abd.h> |
| |
| /* |
| * The ZFS Intent Log (ZIL) saves "transaction records" (itxs) of system |
| * calls that change the file system. Each itx has enough information to |
| * be able to replay them after a system crash, power loss, or |
| * equivalent failure mode. These are stored in memory until either: |
| * |
| * 1. they are committed to the pool by the DMU transaction group |
| * (txg), at which point they can be discarded; or |
| * 2. they are committed to the on-disk ZIL for the dataset being |
| * modified (e.g. due to an fsync, O_DSYNC, or other synchronous |
| * requirement). |
| * |
| * In the event of a crash or power loss, the itxs contained by each |
| * dataset's on-disk ZIL will be replayed when that dataset is first |
| * instantiated (e.g. if the dataset is a normal filesystem, when it is |
| * first mounted). |
| * |
| * As hinted at above, there is one ZIL per dataset (both the in-memory |
| * representation, and the on-disk representation). The on-disk format |
| * consists of 3 parts: |
| * |
| * - a single, per-dataset, ZIL header; which points to a chain of |
| * - zero or more ZIL blocks; each of which contains |
| * - zero or more ZIL records |
| * |
| * A ZIL record holds the information necessary to replay a single |
| * system call transaction. A ZIL block can hold many ZIL records, and |
| * the blocks are chained together, similarly to a singly linked list. |
| * |
| * Each ZIL block contains a block pointer (blkptr_t) to the next ZIL |
| * block in the chain, and the ZIL header points to the first block in |
| * the chain. |
| * |
| * Note, there is not a fixed place in the pool to hold these ZIL |
| * blocks; they are dynamically allocated and freed as needed from the |
| * blocks available on the pool, though they can be preferentially |
| * allocated from a dedicated "log" vdev. |
| */ |
| |
| /* |
| * This controls the amount of time that a ZIL block (lwb) will remain |
| * "open" when it isn't "full", and it has a thread waiting for it to be |
| * committed to stable storage. Please refer to the zil_commit_waiter() |
| * function (and the comments within it) for more details. |
| */ |
| int zfs_commit_timeout_pct = 5; |
| |
| /* |
| * See zil.h for more information about these fields. |
| */ |
| zil_stats_t zil_stats = { |
| { "zil_commit_count", KSTAT_DATA_UINT64 }, |
| { "zil_commit_writer_count", KSTAT_DATA_UINT64 }, |
| { "zil_itx_count", KSTAT_DATA_UINT64 }, |
| { "zil_itx_indirect_count", KSTAT_DATA_UINT64 }, |
| { "zil_itx_indirect_bytes", KSTAT_DATA_UINT64 }, |
| { "zil_itx_copied_count", KSTAT_DATA_UINT64 }, |
| { "zil_itx_copied_bytes", KSTAT_DATA_UINT64 }, |
| { "zil_itx_needcopy_count", KSTAT_DATA_UINT64 }, |
| { "zil_itx_needcopy_bytes", KSTAT_DATA_UINT64 }, |
| { "zil_itx_metaslab_normal_count", KSTAT_DATA_UINT64 }, |
| { "zil_itx_metaslab_normal_bytes", KSTAT_DATA_UINT64 }, |
| { "zil_itx_metaslab_slog_count", KSTAT_DATA_UINT64 }, |
| { "zil_itx_metaslab_slog_bytes", KSTAT_DATA_UINT64 }, |
| }; |
| |
| static kstat_t *zil_ksp; |
| |
| /* |
| * Disable intent logging replay. This global ZIL switch affects all pools. |
| */ |
| int zil_replay_disable = 0; |
| |
| /* |
| * Disable the DKIOCFLUSHWRITECACHE commands that are normally sent to |
| * the disk(s) by the ZIL after an LWB write has completed. Setting this |
| * will cause ZIL corruption on power loss if a volatile out-of-order |
| * write cache is enabled. |
| */ |
| int zil_nocacheflush = 0; |
| |
| /* |
| * Limit SLOG write size per commit executed with synchronous priority. |
| * Any writes above that will be executed with lower (asynchronous) priority |
| * to limit potential SLOG device abuse by single active ZIL writer. |
| */ |
| unsigned long zil_slog_bulk = 768 * 1024; |
| |
| static kmem_cache_t *zil_lwb_cache; |
| static kmem_cache_t *zil_zcw_cache; |
| |
| static void zil_async_to_sync(zilog_t *zilog, uint64_t foid); |
| |
| #define LWB_EMPTY(lwb) ((BP_GET_LSIZE(&lwb->lwb_blk) - \ |
| sizeof (zil_chain_t)) == (lwb->lwb_sz - lwb->lwb_nused)) |
| |
| static int |
| zil_bp_compare(const void *x1, const void *x2) |
| { |
| const dva_t *dva1 = &((zil_bp_node_t *)x1)->zn_dva; |
| const dva_t *dva2 = &((zil_bp_node_t *)x2)->zn_dva; |
| |
| int cmp = AVL_CMP(DVA_GET_VDEV(dva1), DVA_GET_VDEV(dva2)); |
| if (likely(cmp)) |
| return (cmp); |
| |
| return (AVL_CMP(DVA_GET_OFFSET(dva1), DVA_GET_OFFSET(dva2))); |
| } |
| |
| static void |
| zil_bp_tree_init(zilog_t *zilog) |
| { |
| avl_create(&zilog->zl_bp_tree, zil_bp_compare, |
| sizeof (zil_bp_node_t), offsetof(zil_bp_node_t, zn_node)); |
| } |
| |
| static void |
| zil_bp_tree_fini(zilog_t *zilog) |
| { |
| avl_tree_t *t = &zilog->zl_bp_tree; |
| zil_bp_node_t *zn; |
| void *cookie = NULL; |
| |
| while ((zn = avl_destroy_nodes(t, &cookie)) != NULL) |
| kmem_free(zn, sizeof (zil_bp_node_t)); |
| |
| avl_destroy(t); |
| } |
| |
| int |
| zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp) |
| { |
| avl_tree_t *t = &zilog->zl_bp_tree; |
| const dva_t *dva; |
| zil_bp_node_t *zn; |
| avl_index_t where; |
| |
| if (BP_IS_EMBEDDED(bp)) |
| return (0); |
| |
| dva = BP_IDENTITY(bp); |
| |
| if (avl_find(t, dva, &where) != NULL) |
| return (SET_ERROR(EEXIST)); |
| |
| zn = kmem_alloc(sizeof (zil_bp_node_t), KM_SLEEP); |
| zn->zn_dva = *dva; |
| avl_insert(t, zn, where); |
| |
| return (0); |
| } |
| |
| static zil_header_t * |
| zil_header_in_syncing_context(zilog_t *zilog) |
| { |
| return ((zil_header_t *)zilog->zl_header); |
| } |
| |
| static void |
| zil_init_log_chain(zilog_t *zilog, blkptr_t *bp) |
| { |
| zio_cksum_t *zc = &bp->blk_cksum; |
| |
| zc->zc_word[ZIL_ZC_GUID_0] = spa_get_random(-1ULL); |
| zc->zc_word[ZIL_ZC_GUID_1] = spa_get_random(-1ULL); |
| zc->zc_word[ZIL_ZC_OBJSET] = dmu_objset_id(zilog->zl_os); |
| zc->zc_word[ZIL_ZC_SEQ] = 1ULL; |
| } |
| |
| /* |
| * Read a log block and make sure it's valid. |
| */ |
| static int |
| zil_read_log_block(zilog_t *zilog, boolean_t decrypt, const blkptr_t *bp, |
| blkptr_t *nbp, void *dst, char **end) |
| { |
| enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; |
| arc_flags_t aflags = ARC_FLAG_WAIT; |
| arc_buf_t *abuf = NULL; |
| zbookmark_phys_t zb; |
| int error; |
| |
| if (zilog->zl_header->zh_claim_txg == 0) |
| zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; |
| |
| if (!(zilog->zl_header->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) |
| zio_flags |= ZIO_FLAG_SPECULATIVE; |
| |
| if (!decrypt) |
| zio_flags |= ZIO_FLAG_RAW; |
| |
| SET_BOOKMARK(&zb, bp->blk_cksum.zc_word[ZIL_ZC_OBJSET], |
| ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); |
| |
| error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, |
| &abuf, ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); |
| |
| if (error == 0) { |
| zio_cksum_t cksum = bp->blk_cksum; |
| |
| /* |
| * Validate the checksummed log block. |
| * |
| * Sequence numbers should be... sequential. The checksum |
| * verifier for the next block should be bp's checksum plus 1. |
| * |
| * Also check the log chain linkage and size used. |
| */ |
| cksum.zc_word[ZIL_ZC_SEQ]++; |
| |
| if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { |
| zil_chain_t *zilc = abuf->b_data; |
| char *lr = (char *)(zilc + 1); |
| uint64_t len = zilc->zc_nused - sizeof (zil_chain_t); |
| |
| if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, |
| sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk)) { |
| error = SET_ERROR(ECKSUM); |
| } else { |
| ASSERT3U(len, <=, SPA_OLD_MAXBLOCKSIZE); |
| bcopy(lr, dst, len); |
| *end = (char *)dst + len; |
| *nbp = zilc->zc_next_blk; |
| } |
| } else { |
| char *lr = abuf->b_data; |
| uint64_t size = BP_GET_LSIZE(bp); |
| zil_chain_t *zilc = (zil_chain_t *)(lr + size) - 1; |
| |
| if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum, |
| sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk) || |
| (zilc->zc_nused > (size - sizeof (*zilc)))) { |
| error = SET_ERROR(ECKSUM); |
| } else { |
| ASSERT3U(zilc->zc_nused, <=, |
| SPA_OLD_MAXBLOCKSIZE); |
| bcopy(lr, dst, zilc->zc_nused); |
| *end = (char *)dst + zilc->zc_nused; |
| *nbp = zilc->zc_next_blk; |
| } |
| } |
| |
| arc_buf_destroy(abuf, &abuf); |
| } |
| |
| return (error); |
| } |
| |
| /* |
| * Read a TX_WRITE log data block. |
| */ |
| static int |
| zil_read_log_data(zilog_t *zilog, const lr_write_t *lr, void *wbuf) |
| { |
| enum zio_flag zio_flags = ZIO_FLAG_CANFAIL; |
| const blkptr_t *bp = &lr->lr_blkptr; |
| arc_flags_t aflags = ARC_FLAG_WAIT; |
| arc_buf_t *abuf = NULL; |
| zbookmark_phys_t zb; |
| int error; |
| |
| if (BP_IS_HOLE(bp)) { |
| if (wbuf != NULL) |
| bzero(wbuf, MAX(BP_GET_LSIZE(bp), lr->lr_length)); |
| return (0); |
| } |
| |
| if (zilog->zl_header->zh_claim_txg == 0) |
| zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB; |
| |
| /* |
| * If we are not using the resulting data, we are just checking that |
| * it hasn't been corrupted so we don't need to waste CPU time |
| * decompressing and decrypting it. |
| */ |
| if (wbuf == NULL) |
| zio_flags |= ZIO_FLAG_RAW; |
| |
| SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os), lr->lr_foid, |
| ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp)); |
| |
| error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf, |
| ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb); |
| |
| if (error == 0) { |
| if (wbuf != NULL) |
| bcopy(abuf->b_data, wbuf, arc_buf_size(abuf)); |
| arc_buf_destroy(abuf, &abuf); |
| } |
| |
| return (error); |
| } |
| |
| /* |
| * Parse the intent log, and call parse_func for each valid record within. |
| */ |
| int |
| zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func, |
| zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg, |
| boolean_t decrypt) |
| { |
| const zil_header_t *zh = zilog->zl_header; |
| boolean_t claimed = !!zh->zh_claim_txg; |
| uint64_t claim_blk_seq = claimed ? zh->zh_claim_blk_seq : UINT64_MAX; |
| uint64_t claim_lr_seq = claimed ? zh->zh_claim_lr_seq : UINT64_MAX; |
| uint64_t max_blk_seq = 0; |
| uint64_t max_lr_seq = 0; |
| uint64_t blk_count = 0; |
| uint64_t lr_count = 0; |
| blkptr_t blk, next_blk; |
| char *lrbuf, *lrp; |
| int error = 0; |
| |
| bzero(&next_blk, sizeof (blkptr_t)); |
| |
| /* |
| * Old logs didn't record the maximum zh_claim_lr_seq. |
| */ |
| if (!(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID)) |
| claim_lr_seq = UINT64_MAX; |
| |
| /* |
| * Starting at the block pointed to by zh_log we read the log chain. |
| * For each block in the chain we strongly check that block to |
| * ensure its validity. We stop when an invalid block is found. |
| * For each block pointer in the chain we call parse_blk_func(). |
| * For each record in each valid block we call parse_lr_func(). |
| * If the log has been claimed, stop if we encounter a sequence |
| * number greater than the highest claimed sequence number. |
| */ |
| lrbuf = zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE); |
| zil_bp_tree_init(zilog); |
| |
| for (blk = zh->zh_log; !BP_IS_HOLE(&blk); blk = next_blk) { |
| uint64_t blk_seq = blk.blk_cksum.zc_word[ZIL_ZC_SEQ]; |
| int reclen; |
| char *end = NULL; |
| |
| if (blk_seq > claim_blk_seq) |
| break; |
| |
| error = parse_blk_func(zilog, &blk, arg, txg); |
| if (error != 0) |
| break; |
| ASSERT3U(max_blk_seq, <, blk_seq); |
| max_blk_seq = blk_seq; |
| blk_count++; |
| |
| if (max_lr_seq == claim_lr_seq && max_blk_seq == claim_blk_seq) |
| break; |
| |
| error = zil_read_log_block(zilog, decrypt, &blk, &next_blk, |
| lrbuf, &end); |
| if (error != 0) |
| break; |
| |
| for (lrp = lrbuf; lrp < end; lrp += reclen) { |
| lr_t *lr = (lr_t *)lrp; |
| reclen = lr->lrc_reclen; |
| ASSERT3U(reclen, >=, sizeof (lr_t)); |
| if (lr->lrc_seq > claim_lr_seq) |
| goto done; |
| |
| error = parse_lr_func(zilog, lr, arg, txg); |
| if (error != 0) |
| goto done; |
| ASSERT3U(max_lr_seq, <, lr->lrc_seq); |
| max_lr_seq = lr->lrc_seq; |
| lr_count++; |
| } |
| } |
| done: |
| zilog->zl_parse_error = error; |
| zilog->zl_parse_blk_seq = max_blk_seq; |
| zilog->zl_parse_lr_seq = max_lr_seq; |
| zilog->zl_parse_blk_count = blk_count; |
| zilog->zl_parse_lr_count = lr_count; |
| |
| ASSERT(!claimed || !(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID) || |
| (max_blk_seq == claim_blk_seq && max_lr_seq == claim_lr_seq) || |
| (decrypt && error == EIO)); |
| |
| zil_bp_tree_fini(zilog); |
| zio_buf_free(lrbuf, SPA_OLD_MAXBLOCKSIZE); |
| |
| return (error); |
| } |
| |
| /* ARGSUSED */ |
| static int |
| zil_clear_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t first_txg) |
| { |
| ASSERT(!BP_IS_HOLE(bp)); |
| |
| /* |
| * As we call this function from the context of a rewind to a |
| * checkpoint, each ZIL block whose txg is later than the txg |
| * that we rewind to is invalid. Thus, we return -1 so |
| * zil_parse() doesn't attempt to read it. |
| */ |
| if (bp->blk_birth >= first_txg) |
| return (-1); |
| |
| if (zil_bp_tree_add(zilog, bp) != 0) |
| return (0); |
| |
| zio_free(zilog->zl_spa, first_txg, bp); |
| return (0); |
| } |
| |
| /* ARGSUSED */ |
| static int |
| zil_noop_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t first_txg) |
| { |
| return (0); |
| } |
| |
| static int |
| zil_claim_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t first_txg) |
| { |
| /* |
| * Claim log block if not already committed and not already claimed. |
| * If tx == NULL, just verify that the block is claimable. |
| */ |
| if (BP_IS_HOLE(bp) || bp->blk_birth < first_txg || |
| zil_bp_tree_add(zilog, bp) != 0) |
| return (0); |
| |
| return (zio_wait(zio_claim(NULL, zilog->zl_spa, |
| tx == NULL ? 0 : first_txg, bp, spa_claim_notify, NULL, |
| ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB))); |
| } |
| |
| static int |
| zil_claim_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t first_txg) |
| { |
| lr_write_t *lr = (lr_write_t *)lrc; |
| int error; |
| |
| if (lrc->lrc_txtype != TX_WRITE) |
| return (0); |
| |
| /* |
| * If the block is not readable, don't claim it. This can happen |
| * in normal operation when a log block is written to disk before |
| * some of the dmu_sync() blocks it points to. In this case, the |
| * transaction cannot have been committed to anyone (we would have |
| * waited for all writes to be stable first), so it is semantically |
| * correct to declare this the end of the log. |
| */ |
| if (lr->lr_blkptr.blk_birth >= first_txg) { |
| error = zil_read_log_data(zilog, lr, NULL); |
| if (error != 0) |
| return (error); |
| } |
| |
| return (zil_claim_log_block(zilog, &lr->lr_blkptr, tx, first_txg)); |
| } |
| |
| /* ARGSUSED */ |
| static int |
| zil_free_log_block(zilog_t *zilog, blkptr_t *bp, void *tx, uint64_t claim_txg) |
| { |
| zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp); |
| |
| return (0); |
| } |
| |
| static int |
| zil_free_log_record(zilog_t *zilog, lr_t *lrc, void *tx, uint64_t claim_txg) |
| { |
| lr_write_t *lr = (lr_write_t *)lrc; |
| blkptr_t *bp = &lr->lr_blkptr; |
| |
| /* |
| * If we previously claimed it, we need to free it. |
| */ |
| if (claim_txg != 0 && lrc->lrc_txtype == TX_WRITE && |
| bp->blk_birth >= claim_txg && zil_bp_tree_add(zilog, bp) == 0 && |
| !BP_IS_HOLE(bp)) |
| zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp); |
| |
| return (0); |
| } |
| |
| static int |
| zil_lwb_vdev_compare(const void *x1, const void *x2) |
| { |
| const uint64_t v1 = ((zil_vdev_node_t *)x1)->zv_vdev; |
| const uint64_t v2 = ((zil_vdev_node_t *)x2)->zv_vdev; |
| |
| return (AVL_CMP(v1, v2)); |
| } |
| |
| static lwb_t * |
| zil_alloc_lwb(zilog_t *zilog, blkptr_t *bp, boolean_t slog, uint64_t txg, |
| boolean_t fastwrite) |
| { |
| lwb_t *lwb; |
| |
| lwb = kmem_cache_alloc(zil_lwb_cache, KM_SLEEP); |
| lwb->lwb_zilog = zilog; |
| lwb->lwb_blk = *bp; |
| lwb->lwb_fastwrite = fastwrite; |
| lwb->lwb_slog = slog; |
| lwb->lwb_state = LWB_STATE_CLOSED; |
| lwb->lwb_buf = zio_buf_alloc(BP_GET_LSIZE(bp)); |
| lwb->lwb_max_txg = txg; |
| lwb->lwb_write_zio = NULL; |
| lwb->lwb_root_zio = NULL; |
| lwb->lwb_tx = NULL; |
| lwb->lwb_issued_timestamp = 0; |
| if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { |
| lwb->lwb_nused = sizeof (zil_chain_t); |
| lwb->lwb_sz = BP_GET_LSIZE(bp); |
| } else { |
| lwb->lwb_nused = 0; |
| lwb->lwb_sz = BP_GET_LSIZE(bp) - sizeof (zil_chain_t); |
| } |
| |
| mutex_enter(&zilog->zl_lock); |
| list_insert_tail(&zilog->zl_lwb_list, lwb); |
| mutex_exit(&zilog->zl_lock); |
| |
| ASSERT(!MUTEX_HELD(&lwb->lwb_vdev_lock)); |
| ASSERT(avl_is_empty(&lwb->lwb_vdev_tree)); |
| VERIFY(list_is_empty(&lwb->lwb_waiters)); |
| VERIFY(list_is_empty(&lwb->lwb_itxs)); |
| |
| return (lwb); |
| } |
| |
| static void |
| zil_free_lwb(zilog_t *zilog, lwb_t *lwb) |
| { |
| ASSERT(MUTEX_HELD(&zilog->zl_lock)); |
| ASSERT(!MUTEX_HELD(&lwb->lwb_vdev_lock)); |
| VERIFY(list_is_empty(&lwb->lwb_waiters)); |
| VERIFY(list_is_empty(&lwb->lwb_itxs)); |
| ASSERT(avl_is_empty(&lwb->lwb_vdev_tree)); |
| ASSERT3P(lwb->lwb_write_zio, ==, NULL); |
| ASSERT3P(lwb->lwb_root_zio, ==, NULL); |
| ASSERT3U(lwb->lwb_max_txg, <=, spa_syncing_txg(zilog->zl_spa)); |
| ASSERT(lwb->lwb_state == LWB_STATE_CLOSED || |
| lwb->lwb_state == LWB_STATE_FLUSH_DONE); |
| |
| /* |
| * Clear the zilog's field to indicate this lwb is no longer |
| * valid, and prevent use-after-free errors. |
| */ |
| if (zilog->zl_last_lwb_opened == lwb) |
| zilog->zl_last_lwb_opened = NULL; |
| |
| kmem_cache_free(zil_lwb_cache, lwb); |
| } |
| |
| /* |
| * Called when we create in-memory log transactions so that we know |
| * to cleanup the itxs at the end of spa_sync(). |
| */ |
| void |
| zilog_dirty(zilog_t *zilog, uint64_t txg) |
| { |
| dsl_pool_t *dp = zilog->zl_dmu_pool; |
| dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); |
| |
| ASSERT(spa_writeable(zilog->zl_spa)); |
| |
| if (ds->ds_is_snapshot) |
| panic("dirtying snapshot!"); |
| |
| if (txg_list_add(&dp->dp_dirty_zilogs, zilog, txg)) { |
| /* up the hold count until we can be written out */ |
| dmu_buf_add_ref(ds->ds_dbuf, zilog); |
| |
| zilog->zl_dirty_max_txg = MAX(txg, zilog->zl_dirty_max_txg); |
| } |
| } |
| |
| /* |
| * Determine if the zil is dirty in the specified txg. Callers wanting to |
| * ensure that the dirty state does not change must hold the itxg_lock for |
| * the specified txg. Holding the lock will ensure that the zil cannot be |
| * dirtied (zil_itx_assign) or cleaned (zil_clean) while we check its current |
| * state. |
| */ |
| boolean_t |
| zilog_is_dirty_in_txg(zilog_t *zilog, uint64_t txg) |
| { |
| dsl_pool_t *dp = zilog->zl_dmu_pool; |
| |
| if (txg_list_member(&dp->dp_dirty_zilogs, zilog, txg & TXG_MASK)) |
| return (B_TRUE); |
| return (B_FALSE); |
| } |
| |
| /* |
| * Determine if the zil is dirty. The zil is considered dirty if it has |
| * any pending itx records that have not been cleaned by zil_clean(). |
| */ |
| boolean_t |
| zilog_is_dirty(zilog_t *zilog) |
| { |
| dsl_pool_t *dp = zilog->zl_dmu_pool; |
| |
| for (int t = 0; t < TXG_SIZE; t++) { |
| if (txg_list_member(&dp->dp_dirty_zilogs, zilog, t)) |
| return (B_TRUE); |
| } |
| return (B_FALSE); |
| } |
| |
| /* |
| * Create an on-disk intent log. |
| */ |
| static lwb_t * |
| zil_create(zilog_t *zilog) |
| { |
| const zil_header_t *zh = zilog->zl_header; |
| lwb_t *lwb = NULL; |
| uint64_t txg = 0; |
| dmu_tx_t *tx = NULL; |
| blkptr_t blk; |
| int error = 0; |
| boolean_t fastwrite = FALSE; |
| boolean_t slog = FALSE; |
| |
| /* |
| * Wait for any previous destroy to complete. |
| */ |
| txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); |
| |
| ASSERT(zh->zh_claim_txg == 0); |
| ASSERT(zh->zh_replay_seq == 0); |
| |
| blk = zh->zh_log; |
| |
| /* |
| * Allocate an initial log block if: |
| * - there isn't one already |
| * - the existing block is the wrong endianness |
| */ |
| if (BP_IS_HOLE(&blk) || BP_SHOULD_BYTESWAP(&blk)) { |
| tx = dmu_tx_create(zilog->zl_os); |
| VERIFY0(dmu_tx_assign(tx, TXG_WAIT)); |
| dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); |
| txg = dmu_tx_get_txg(tx); |
| |
| if (!BP_IS_HOLE(&blk)) { |
| zio_free(zilog->zl_spa, txg, &blk); |
| BP_ZERO(&blk); |
| } |
| |
| error = zio_alloc_zil(zilog->zl_spa, zilog->zl_os, txg, &blk, |
| ZIL_MIN_BLKSZ, &slog); |
| fastwrite = TRUE; |
| |
| if (error == 0) |
| zil_init_log_chain(zilog, &blk); |
| } |
| |
| /* |
| * Allocate a log write block (lwb) for the first log block. |
| */ |
| if (error == 0) |
| lwb = zil_alloc_lwb(zilog, &blk, slog, txg, fastwrite); |
| |
| /* |
| * If we just allocated the first log block, commit our transaction |
| * and wait for zil_sync() to stuff the block pointer into zh_log. |
| * (zh is part of the MOS, so we cannot modify it in open context.) |
| */ |
| if (tx != NULL) { |
| dmu_tx_commit(tx); |
| txg_wait_synced(zilog->zl_dmu_pool, txg); |
| } |
| |
| ASSERT(error != 0 || bcmp(&blk, &zh->zh_log, sizeof (blk)) == 0); |
| IMPLY(error == 0, lwb != NULL); |
| |
| return (lwb); |
| } |
| |
| /* |
| * In one tx, free all log blocks and clear the log header. If keep_first |
| * is set, then we're replaying a log with no content. We want to keep the |
| * first block, however, so that the first synchronous transaction doesn't |
| * require a txg_wait_synced() in zil_create(). We don't need to |
| * txg_wait_synced() here either when keep_first is set, because both |
| * zil_create() and zil_destroy() will wait for any in-progress destroys |
| * to complete. |
| */ |
| void |
| zil_destroy(zilog_t *zilog, boolean_t keep_first) |
| { |
| const zil_header_t *zh = zilog->zl_header; |
| lwb_t *lwb; |
| dmu_tx_t *tx; |
| uint64_t txg; |
| |
| /* |
| * Wait for any previous destroy to complete. |
| */ |
| txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); |
| |
| zilog->zl_old_header = *zh; /* debugging aid */ |
| |
| if (BP_IS_HOLE(&zh->zh_log)) |
| return; |
| |
| tx = dmu_tx_create(zilog->zl_os); |
| VERIFY0(dmu_tx_assign(tx, TXG_WAIT)); |
| dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); |
| txg = dmu_tx_get_txg(tx); |
| |
| mutex_enter(&zilog->zl_lock); |
| |
| ASSERT3U(zilog->zl_destroy_txg, <, txg); |
| zilog->zl_destroy_txg = txg; |
| zilog->zl_keep_first = keep_first; |
| |
| if (!list_is_empty(&zilog->zl_lwb_list)) { |
| ASSERT(zh->zh_claim_txg == 0); |
| VERIFY(!keep_first); |
| while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { |
| if (lwb->lwb_fastwrite) |
| metaslab_fastwrite_unmark(zilog->zl_spa, |
| &lwb->lwb_blk); |
| |
| list_remove(&zilog->zl_lwb_list, lwb); |
| if (lwb->lwb_buf != NULL) |
| zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); |
| zio_free(zilog->zl_spa, txg, &lwb->lwb_blk); |
| zil_free_lwb(zilog, lwb); |
| } |
| } else if (!keep_first) { |
| zil_destroy_sync(zilog, tx); |
| } |
| mutex_exit(&zilog->zl_lock); |
| |
| dmu_tx_commit(tx); |
| } |
| |
| void |
| zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx) |
| { |
| ASSERT(list_is_empty(&zilog->zl_lwb_list)); |
| (void) zil_parse(zilog, zil_free_log_block, |
| zil_free_log_record, tx, zilog->zl_header->zh_claim_txg, B_FALSE); |
| } |
| |
| int |
| zil_claim(dsl_pool_t *dp, dsl_dataset_t *ds, void *txarg) |
| { |
| dmu_tx_t *tx = txarg; |
| zilog_t *zilog; |
| uint64_t first_txg; |
| zil_header_t *zh; |
| objset_t *os; |
| int error; |
| |
| error = dmu_objset_own_obj(dp, ds->ds_object, |
| DMU_OST_ANY, B_FALSE, B_FALSE, FTAG, &os); |
| if (error != 0) { |
| /* |
| * EBUSY indicates that the objset is inconsistent, in which |
| * case it can not have a ZIL. |
| */ |
| if (error != EBUSY) { |
| cmn_err(CE_WARN, "can't open objset for %llu, error %u", |
| (unsigned long long)ds->ds_object, error); |
| } |
| |
| return (0); |
| } |
| |
| zilog = dmu_objset_zil(os); |
| zh = zil_header_in_syncing_context(zilog); |
| ASSERT3U(tx->tx_txg, ==, spa_first_txg(zilog->zl_spa)); |
| first_txg = spa_min_claim_txg(zilog->zl_spa); |
| |
| /* |
| * If the spa_log_state is not set to be cleared, check whether |
| * the current uberblock is a checkpoint one and if the current |
| * header has been claimed before moving on. |
| * |
| * If the current uberblock is a checkpointed uberblock then |
| * one of the following scenarios took place: |
| * |
| * 1] We are currently rewinding to the checkpoint of the pool. |
| * 2] We crashed in the middle of a checkpoint rewind but we |
| * did manage to write the checkpointed uberblock to the |
| * vdev labels, so when we tried to import the pool again |
| * the checkpointed uberblock was selected from the import |
| * procedure. |
| * |
| * In both cases we want to zero out all the ZIL blocks, except |
| * the ones that have been claimed at the time of the checkpoint |
| * (their zh_claim_txg != 0). The reason is that these blocks |
| * may be corrupted since we may have reused their locations on |
| * disk after we took the checkpoint. |
| * |
| * We could try to set spa_log_state to SPA_LOG_CLEAR earlier |
| * when we first figure out whether the current uberblock is |
| * checkpointed or not. Unfortunately, that would discard all |
| * the logs, including the ones that are claimed, and we would |
| * leak space. |
| */ |
| if (spa_get_log_state(zilog->zl_spa) == SPA_LOG_CLEAR || |
| (zilog->zl_spa->spa_uberblock.ub_checkpoint_txg != 0 && |
| zh->zh_claim_txg == 0)) { |
| if (!BP_IS_HOLE(&zh->zh_log)) { |
| (void) zil_parse(zilog, zil_clear_log_block, |
| zil_noop_log_record, tx, first_txg, B_FALSE); |
| } |
| BP_ZERO(&zh->zh_log); |
| if (os->os_encrypted) |
| os->os_next_write_raw[tx->tx_txg & TXG_MASK] = B_TRUE; |
| dsl_dataset_dirty(dmu_objset_ds(os), tx); |
| dmu_objset_disown(os, B_FALSE, FTAG); |
| return (0); |
| } |
| |
| /* |
| * If we are not rewinding and opening the pool normally, then |
| * the min_claim_txg should be equal to the first txg of the pool. |
| */ |
| ASSERT3U(first_txg, ==, spa_first_txg(zilog->zl_spa)); |
| |
| /* |
| * Claim all log blocks if we haven't already done so, and remember |
| * the highest claimed sequence number. This ensures that if we can |
| * read only part of the log now (e.g. due to a missing device), |
| * but we can read the entire log later, we will not try to replay |
| * or destroy beyond the last block we successfully claimed. |
| */ |
| ASSERT3U(zh->zh_claim_txg, <=, first_txg); |
| if (zh->zh_claim_txg == 0 && !BP_IS_HOLE(&zh->zh_log)) { |
| (void) zil_parse(zilog, zil_claim_log_block, |
| zil_claim_log_record, tx, first_txg, B_FALSE); |
| zh->zh_claim_txg = first_txg; |
| zh->zh_claim_blk_seq = zilog->zl_parse_blk_seq; |
| zh->zh_claim_lr_seq = zilog->zl_parse_lr_seq; |
| if (zilog->zl_parse_lr_count || zilog->zl_parse_blk_count > 1) |
| zh->zh_flags |= ZIL_REPLAY_NEEDED; |
| zh->zh_flags |= ZIL_CLAIM_LR_SEQ_VALID; |
| if (os->os_encrypted) |
| os->os_next_write_raw[tx->tx_txg & TXG_MASK] = B_TRUE; |
| dsl_dataset_dirty(dmu_objset_ds(os), tx); |
| } |
| |
| ASSERT3U(first_txg, ==, (spa_last_synced_txg(zilog->zl_spa) + 1)); |
| dmu_objset_disown(os, B_FALSE, FTAG); |
| return (0); |
| } |
| |
| /* |
| * Check the log by walking the log chain. |
| * Checksum errors are ok as they indicate the end of the chain. |
| * Any other error (no device or read failure) returns an error. |
| */ |
| /* ARGSUSED */ |
| int |
| zil_check_log_chain(dsl_pool_t *dp, dsl_dataset_t *ds, void *tx) |
| { |
| zilog_t *zilog; |
| objset_t *os; |
| blkptr_t *bp; |
| int error; |
| |
| ASSERT(tx == NULL); |
| |
| error = dmu_objset_from_ds(ds, &os); |
| if (error != 0) { |
| cmn_err(CE_WARN, "can't open objset %llu, error %d", |
| (unsigned long long)ds->ds_object, error); |
| return (0); |
| } |
| |
| zilog = dmu_objset_zil(os); |
| bp = (blkptr_t *)&zilog->zl_header->zh_log; |
| |
| if (!BP_IS_HOLE(bp)) { |
| vdev_t *vd; |
| boolean_t valid = B_TRUE; |
| |
| /* |
| * Check the first block and determine if it's on a log device |
| * which may have been removed or faulted prior to loading this |
| * pool. If so, there's no point in checking the rest of the |
| * log as its content should have already been synced to the |
| * pool. |
| */ |
| spa_config_enter(os->os_spa, SCL_STATE, FTAG, RW_READER); |
| vd = vdev_lookup_top(os->os_spa, DVA_GET_VDEV(&bp->blk_dva[0])); |
| if (vd->vdev_islog && vdev_is_dead(vd)) |
| valid = vdev_log_state_valid(vd); |
| spa_config_exit(os->os_spa, SCL_STATE, FTAG); |
| |
| if (!valid) |
| return (0); |
| |
| /* |
| * Check whether the current uberblock is checkpointed (e.g. |
| * we are rewinding) and whether the current header has been |
| * claimed or not. If it hasn't then skip verifying it. We |
| * do this because its ZIL blocks may be part of the pool's |
| * state before the rewind, which is no longer valid. |
| */ |
| zil_header_t *zh = zil_header_in_syncing_context(zilog); |
| if (zilog->zl_spa->spa_uberblock.ub_checkpoint_txg != 0 && |
| zh->zh_claim_txg == 0) |
| return (0); |
| } |
| |
| /* |
| * Because tx == NULL, zil_claim_log_block() will not actually claim |
| * any blocks, but just determine whether it is possible to do so. |
| * In addition to checking the log chain, zil_claim_log_block() |
| * will invoke zio_claim() with a done func of spa_claim_notify(), |
| * which will update spa_max_claim_txg. See spa_load() for details. |
| */ |
| error = zil_parse(zilog, zil_claim_log_block, zil_claim_log_record, tx, |
| zilog->zl_header->zh_claim_txg ? -1ULL : |
| spa_min_claim_txg(os->os_spa), B_FALSE); |
| |
| return ((error == ECKSUM || error == ENOENT) ? 0 : error); |
| } |
| |
| /* |
| * When an itx is "skipped", this function is used to properly mark the |
| * waiter as "done, and signal any thread(s) waiting on it. An itx can |
| * be skipped (and not committed to an lwb) for a variety of reasons, |
| * one of them being that the itx was committed via spa_sync(), prior to |
| * it being committed to an lwb; this can happen if a thread calling |
| * zil_commit() is racing with spa_sync(). |
| */ |
| static void |
| zil_commit_waiter_skip(zil_commit_waiter_t *zcw) |
| { |
| mutex_enter(&zcw->zcw_lock); |
| ASSERT3B(zcw->zcw_done, ==, B_FALSE); |
| zcw->zcw_done = B_TRUE; |
| cv_broadcast(&zcw->zcw_cv); |
| mutex_exit(&zcw->zcw_lock); |
| } |
| |
| /* |
| * This function is used when the given waiter is to be linked into an |
| * lwb's "lwb_waiter" list; i.e. when the itx is committed to the lwb. |
| * At this point, the waiter will no longer be referenced by the itx, |
| * and instead, will be referenced by the lwb. |
| */ |
| static void |
| zil_commit_waiter_link_lwb(zil_commit_waiter_t *zcw, lwb_t *lwb) |
| { |
| /* |
| * The lwb_waiters field of the lwb is protected by the zilog's |
| * zl_lock, thus it must be held when calling this function. |
| */ |
| ASSERT(MUTEX_HELD(&lwb->lwb_zilog->zl_lock)); |
| |
| mutex_enter(&zcw->zcw_lock); |
| ASSERT(!list_link_active(&zcw->zcw_node)); |
| ASSERT3P(zcw->zcw_lwb, ==, NULL); |
| ASSERT3P(lwb, !=, NULL); |
| ASSERT(lwb->lwb_state == LWB_STATE_OPENED || |
| lwb->lwb_state == LWB_STATE_ISSUED || |
| lwb->lwb_state == LWB_STATE_WRITE_DONE); |
| |
| list_insert_tail(&lwb->lwb_waiters, zcw); |
| zcw->zcw_lwb = lwb; |
| mutex_exit(&zcw->zcw_lock); |
| } |
| |
| /* |
| * This function is used when zio_alloc_zil() fails to allocate a ZIL |
| * block, and the given waiter must be linked to the "nolwb waiters" |
| * list inside of zil_process_commit_list(). |
| */ |
| static void |
| zil_commit_waiter_link_nolwb(zil_commit_waiter_t *zcw, list_t *nolwb) |
| { |
| mutex_enter(&zcw->zcw_lock); |
| ASSERT(!list_link_active(&zcw->zcw_node)); |
| ASSERT3P(zcw->zcw_lwb, ==, NULL); |
| list_insert_tail(nolwb, zcw); |
| mutex_exit(&zcw->zcw_lock); |
| } |
| |
| void |
| zil_lwb_add_block(lwb_t *lwb, const blkptr_t *bp) |
| { |
| avl_tree_t *t = &lwb->lwb_vdev_tree; |
| avl_index_t where; |
| zil_vdev_node_t *zv, zvsearch; |
| int ndvas = BP_GET_NDVAS(bp); |
| int i; |
| |
| if (zil_nocacheflush) |
| return; |
| |
| mutex_enter(&lwb->lwb_vdev_lock); |
| for (i = 0; i < ndvas; i++) { |
| zvsearch.zv_vdev = DVA_GET_VDEV(&bp->blk_dva[i]); |
| if (avl_find(t, &zvsearch, &where) == NULL) { |
| zv = kmem_alloc(sizeof (*zv), KM_SLEEP); |
| zv->zv_vdev = zvsearch.zv_vdev; |
| avl_insert(t, zv, where); |
| } |
| } |
| mutex_exit(&lwb->lwb_vdev_lock); |
| } |
| |
| static void |
| zil_lwb_flush_defer(lwb_t *lwb, lwb_t *nlwb) |
| { |
| avl_tree_t *src = &lwb->lwb_vdev_tree; |
| avl_tree_t *dst = &nlwb->lwb_vdev_tree; |
| void *cookie = NULL; |
| zil_vdev_node_t *zv; |
| |
| ASSERT3S(lwb->lwb_state, ==, LWB_STATE_WRITE_DONE); |
| ASSERT3S(nlwb->lwb_state, !=, LWB_STATE_WRITE_DONE); |
| ASSERT3S(nlwb->lwb_state, !=, LWB_STATE_FLUSH_DONE); |
| |
| /* |
| * While 'lwb' is at a point in its lifetime where lwb_vdev_tree does |
| * not need the protection of lwb_vdev_lock (it will only be modified |
| * while holding zilog->zl_lock) as its writes and those of its |
| * children have all completed. The younger 'nlwb' may be waiting on |
| * future writes to additional vdevs. |
| */ |
| mutex_enter(&nlwb->lwb_vdev_lock); |
| /* |
| * Tear down the 'lwb' vdev tree, ensuring that entries which do not |
| * exist in 'nlwb' are moved to it, freeing any would-be duplicates. |
| */ |
| while ((zv = avl_destroy_nodes(src, &cookie)) != NULL) { |
| avl_index_t where; |
| |
| if (avl_find(dst, zv, &where) == NULL) { |
| avl_insert(dst, zv, where); |
| } else { |
| kmem_free(zv, sizeof (*zv)); |
| } |
| } |
| mutex_exit(&nlwb->lwb_vdev_lock); |
| } |
| |
| void |
| zil_lwb_add_txg(lwb_t *lwb, uint64_t txg) |
| { |
| lwb->lwb_max_txg = MAX(lwb->lwb_max_txg, txg); |
| } |
| |
| /* |
| * This function is a called after all vdevs associated with a given lwb |
| * write have completed their DKIOCFLUSHWRITECACHE command; or as soon |
| * as the lwb write completes, if "zil_nocacheflush" is set. Further, |
| * all "previous" lwb's will have completed before this function is |
| * called; i.e. this function is called for all previous lwbs before |
| * it's called for "this" lwb (enforced via zio the dependencies |
| * configured in zil_lwb_set_zio_dependency()). |
| * |
| * The intention is for this function to be called as soon as the |
| * contents of an lwb are considered "stable" on disk, and will survive |
| * any sudden loss of power. At this point, any threads waiting for the |
| * lwb to reach this state are signalled, and the "waiter" structures |
| * are marked "done". |
| */ |
| static void |
| zil_lwb_flush_vdevs_done(zio_t *zio) |
| { |
| lwb_t *lwb = zio->io_private; |
| zilog_t *zilog = lwb->lwb_zilog; |
| dmu_tx_t *tx = lwb->lwb_tx; |
| zil_commit_waiter_t *zcw; |
| itx_t *itx; |
| |
| spa_config_exit(zilog->zl_spa, SCL_STATE, lwb); |
| |
| zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); |
| |
| mutex_enter(&zilog->zl_lock); |
| |
| /* |
| * Ensure the lwb buffer pointer is cleared before releasing the |
| * txg. If we have had an allocation failure and the txg is |
| * waiting to sync then we want zil_sync() to remove the lwb so |
| * that it's not picked up as the next new one in |
| * zil_process_commit_list(). zil_sync() will only remove the |
| * lwb if lwb_buf is null. |
| */ |
| lwb->lwb_buf = NULL; |
| lwb->lwb_tx = NULL; |
| |
| ASSERT3U(lwb->lwb_issued_timestamp, >, 0); |
| zilog->zl_last_lwb_latency = gethrtime() - lwb->lwb_issued_timestamp; |
| |
| lwb->lwb_root_zio = NULL; |
| |
| ASSERT3S(lwb->lwb_state, ==, LWB_STATE_WRITE_DONE); |
| lwb->lwb_state = LWB_STATE_FLUSH_DONE; |
| |
| if (zilog->zl_last_lwb_opened == lwb) { |
| /* |
| * Remember the highest committed log sequence number |
| * for ztest. We only update this value when all the log |
| * writes succeeded, because ztest wants to ASSERT that |
| * it got the whole log chain. |
| */ |
| zilog->zl_commit_lr_seq = zilog->zl_lr_seq; |
| } |
| |
| while ((itx = list_head(&lwb->lwb_itxs)) != NULL) { |
| list_remove(&lwb->lwb_itxs, itx); |
| zil_itx_destroy(itx); |
| } |
| |
| while ((zcw = list_head(&lwb->lwb_waiters)) != NULL) { |
| mutex_enter(&zcw->zcw_lock); |
| |
| ASSERT(list_link_active(&zcw->zcw_node)); |
| list_remove(&lwb->lwb_waiters, zcw); |
| |
| ASSERT3P(zcw->zcw_lwb, ==, lwb); |
| zcw->zcw_lwb = NULL; |
| |
| zcw->zcw_zio_error = zio->io_error; |
| |
| ASSERT3B(zcw->zcw_done, ==, B_FALSE); |
| zcw->zcw_done = B_TRUE; |
| cv_broadcast(&zcw->zcw_cv); |
| |
| mutex_exit(&zcw->zcw_lock); |
| } |
| |
| mutex_exit(&zilog->zl_lock); |
| |
| /* |
| * Now that we've written this log block, we have a stable pointer |
| * to the next block in the chain, so it's OK to let the txg in |
| * which we allocated the next block sync. |
| */ |
| dmu_tx_commit(tx); |
| } |
| |
| /* |
| * This is called when an lwb's write zio completes. The callback's |
| * purpose is to issue the DKIOCFLUSHWRITECACHE commands for the vdevs |
| * in the lwb's lwb_vdev_tree. The tree will contain the vdevs involved |
| * in writing out this specific lwb's data, and in the case that cache |
| * flushes have been deferred, vdevs involved in writing the data for |
| * previous lwbs. The writes corresponding to all the vdevs in the |
| * lwb_vdev_tree will have completed by the time this is called, due to |
| * the zio dependencies configured in zil_lwb_set_zio_dependency(), |
| * which takes deferred flushes into account. The lwb will be "done" |
| * once zil_lwb_flush_vdevs_done() is called, which occurs in the zio |
| * completion callback for the lwb's root zio. |
| */ |
| static void |
| zil_lwb_write_done(zio_t *zio) |
| { |
| lwb_t *lwb = zio->io_private; |
| spa_t *spa = zio->io_spa; |
| zilog_t *zilog = lwb->lwb_zilog; |
| avl_tree_t *t = &lwb->lwb_vdev_tree; |
| void *cookie = NULL; |
| zil_vdev_node_t *zv; |
| lwb_t *nlwb; |
| |
| ASSERT3S(spa_config_held(spa, SCL_STATE, RW_READER), !=, 0); |
| |
| ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF); |
| ASSERT(BP_GET_TYPE(zio->io_bp) == DMU_OT_INTENT_LOG); |
| ASSERT(BP_GET_LEVEL(zio->io_bp) == 0); |
| ASSERT(BP_GET_BYTEORDER(zio->io_bp) == ZFS_HOST_BYTEORDER); |
| ASSERT(!BP_IS_GANG(zio->io_bp)); |
| ASSERT(!BP_IS_HOLE(zio->io_bp)); |
| ASSERT(BP_GET_FILL(zio->io_bp) == 0); |
| |
| abd_put(zio->io_abd); |
| |
| mutex_enter(&zilog->zl_lock); |
| ASSERT3S(lwb->lwb_state, ==, LWB_STATE_ISSUED); |
| lwb->lwb_state = LWB_STATE_WRITE_DONE; |
| lwb->lwb_write_zio = NULL; |
| lwb->lwb_fastwrite = FALSE; |
| nlwb = list_next(&zilog->zl_lwb_list, lwb); |
| mutex_exit(&zilog->zl_lock); |
| |
| if (avl_numnodes(t) == 0) |
| return; |
| |
| /* |
| * If there was an IO error, we're not going to call zio_flush() |
| * on these vdevs, so we simply empty the tree and free the |
| * nodes. We avoid calling zio_flush() since there isn't any |
| * good reason for doing so, after the lwb block failed to be |
| * written out. |
| */ |
| if (zio->io_error != 0) { |
| while ((zv = avl_destroy_nodes(t, &cookie)) != NULL) |
| kmem_free(zv, sizeof (*zv)); |
| return; |
| } |
| |
| /* |
| * If this lwb does not have any threads waiting for it to |
| * complete, we want to defer issuing the DKIOCFLUSHWRITECACHE |
| * command to the vdevs written to by "this" lwb, and instead |
| * rely on the "next" lwb to handle the DKIOCFLUSHWRITECACHE |
| * command for those vdevs. Thus, we merge the vdev tree of |
| * "this" lwb with the vdev tree of the "next" lwb in the list, |
| * and assume the "next" lwb will handle flushing the vdevs (or |
| * deferring the flush(s) again). |
| * |
| * This is a useful performance optimization, especially for |
| * workloads with lots of async write activity and few sync |
| * write and/or fsync activity, as it has the potential to |
| * coalesce multiple flush commands to a vdev into one. |
| */ |
| if (list_head(&lwb->lwb_waiters) == NULL && nlwb != NULL) { |
| zil_lwb_flush_defer(lwb, nlwb); |
| ASSERT(avl_is_empty(&lwb->lwb_vdev_tree)); |
| return; |
| } |
| |
| while ((zv = avl_destroy_nodes(t, &cookie)) != NULL) { |
| vdev_t *vd = vdev_lookup_top(spa, zv->zv_vdev); |
| if (vd != NULL) |
| zio_flush(lwb->lwb_root_zio, vd); |
| kmem_free(zv, sizeof (*zv)); |
| } |
| } |
| |
| static void |
| zil_lwb_set_zio_dependency(zilog_t *zilog, lwb_t *lwb) |
| { |
| lwb_t *last_lwb_opened = zilog->zl_last_lwb_opened; |
| |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| ASSERT(MUTEX_HELD(&zilog->zl_lock)); |
| |
| /* |
| * The zilog's "zl_last_lwb_opened" field is used to build the |
| * lwb/zio dependency chain, which is used to preserve the |
| * ordering of lwb completions that is required by the semantics |
| * of the ZIL. Each new lwb zio becomes a parent of the |
| * "previous" lwb zio, such that the new lwb's zio cannot |
| * complete until the "previous" lwb's zio completes. |
| * |
| * This is required by the semantics of zil_commit(); the commit |
| * waiters attached to the lwbs will be woken in the lwb zio's |
| * completion callback, so this zio dependency graph ensures the |
| * waiters are woken in the correct order (the same order the |
| * lwbs were created). |
| */ |
| if (last_lwb_opened != NULL && |
| last_lwb_opened->lwb_state != LWB_STATE_FLUSH_DONE) { |
| ASSERT(last_lwb_opened->lwb_state == LWB_STATE_OPENED || |
| last_lwb_opened->lwb_state == LWB_STATE_ISSUED || |
| last_lwb_opened->lwb_state == LWB_STATE_WRITE_DONE); |
| |
| ASSERT3P(last_lwb_opened->lwb_root_zio, !=, NULL); |
| zio_add_child(lwb->lwb_root_zio, |
| last_lwb_opened->lwb_root_zio); |
| |
| /* |
| * If the previous lwb's write hasn't already completed, |
| * we also want to order the completion of the lwb write |
| * zios (above, we only order the completion of the lwb |
| * root zios). This is required because of how we can |
| * defer the DKIOCFLUSHWRITECACHE commands for each lwb. |
| * |
| * When the DKIOCFLUSHWRITECACHE commands are deferred, |
| * the previous lwb will rely on this lwb to flush the |
| * vdevs written to by that previous lwb. Thus, we need |
| * to ensure this lwb doesn't issue the flush until |
| * after the previous lwb's write completes. We ensure |
| * this ordering by setting the zio parent/child |
| * relationship here. |
| * |
| * Without this relationship on the lwb's write zio, |
| * it's possible for this lwb's write to complete prior |
| * to the previous lwb's write completing; and thus, the |
| * vdevs for the previous lwb would be flushed prior to |
| * that lwb's data being written to those vdevs (the |
| * vdevs are flushed in the lwb write zio's completion |
| * handler, zil_lwb_write_done()). |
| */ |
| if (last_lwb_opened->lwb_state != LWB_STATE_WRITE_DONE) { |
| ASSERT(last_lwb_opened->lwb_state == LWB_STATE_OPENED || |
| last_lwb_opened->lwb_state == LWB_STATE_ISSUED); |
| |
| ASSERT3P(last_lwb_opened->lwb_write_zio, !=, NULL); |
| zio_add_child(lwb->lwb_write_zio, |
| last_lwb_opened->lwb_write_zio); |
| } |
| } |
| } |
| |
| |
| /* |
| * This function's purpose is to "open" an lwb such that it is ready to |
| * accept new itxs being committed to it. To do this, the lwb's zio |
| * structures are created, and linked to the lwb. This function is |
| * idempotent; if the passed in lwb has already been opened, this |
| * function is essentially a no-op. |
| */ |
| static void |
| zil_lwb_write_open(zilog_t *zilog, lwb_t *lwb) |
| { |
| zbookmark_phys_t zb; |
| zio_priority_t prio; |
| |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| ASSERT3P(lwb, !=, NULL); |
| EQUIV(lwb->lwb_root_zio == NULL, lwb->lwb_state == LWB_STATE_CLOSED); |
| EQUIV(lwb->lwb_root_zio != NULL, lwb->lwb_state == LWB_STATE_OPENED); |
| |
| SET_BOOKMARK(&zb, lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_OBJSET], |
| ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, |
| lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_SEQ]); |
| |
| /* Lock so zil_sync() doesn't fastwrite_unmark after zio is created */ |
| mutex_enter(&zilog->zl_lock); |
| if (lwb->lwb_root_zio == NULL) { |
| abd_t *lwb_abd = abd_get_from_buf(lwb->lwb_buf, |
| BP_GET_LSIZE(&lwb->lwb_blk)); |
| |
| if (!lwb->lwb_fastwrite) { |
| metaslab_fastwrite_mark(zilog->zl_spa, &lwb->lwb_blk); |
| lwb->lwb_fastwrite = 1; |
| } |
| |
| if (!lwb->lwb_slog || zilog->zl_cur_used <= zil_slog_bulk) |
| prio = ZIO_PRIORITY_SYNC_WRITE; |
| else |
| prio = ZIO_PRIORITY_ASYNC_WRITE; |
| |
| lwb->lwb_root_zio = zio_root(zilog->zl_spa, |
| zil_lwb_flush_vdevs_done, lwb, ZIO_FLAG_CANFAIL); |
| ASSERT3P(lwb->lwb_root_zio, !=, NULL); |
| |
| lwb->lwb_write_zio = zio_rewrite(lwb->lwb_root_zio, |
| zilog->zl_spa, 0, &lwb->lwb_blk, lwb_abd, |
| BP_GET_LSIZE(&lwb->lwb_blk), zil_lwb_write_done, lwb, |
| prio, ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | |
| ZIO_FLAG_FASTWRITE, &zb); |
| ASSERT3P(lwb->lwb_write_zio, !=, NULL); |
| |
| lwb->lwb_state = LWB_STATE_OPENED; |
| |
| zil_lwb_set_zio_dependency(zilog, lwb); |
| zilog->zl_last_lwb_opened = lwb; |
| } |
| mutex_exit(&zilog->zl_lock); |
| |
| ASSERT3P(lwb->lwb_root_zio, !=, NULL); |
| ASSERT3P(lwb->lwb_write_zio, !=, NULL); |
| ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED); |
| } |
| |
| /* |
| * Define a limited set of intent log block sizes. |
| * |
| * These must be a multiple of 4KB. Note only the amount used (again |
| * aligned to 4KB) actually gets written. However, we can't always just |
| * allocate SPA_OLD_MAXBLOCKSIZE as the slog space could be exhausted. |
| */ |
| struct { |
| uint64_t limit; |
| uint64_t blksz; |
| } zil_block_buckets[] = { |
| { 4096, 4096 }, /* non TX_WRITE */ |
| { 8192 + 4096, 8192 + 4096 }, /* database */ |
| { 32768 + 4096, 32768 + 4096 }, /* NFS writes */ |
| { 65536 + 4096, 65536 + 4096 }, /* 64KB writes */ |
| { 131072, 131072 }, /* < 128KB writes */ |
| { 131072 +4096, 65536 + 4096 }, /* 128KB writes */ |
| { UINT64_MAX, SPA_OLD_MAXBLOCKSIZE}, /* > 128KB writes */ |
| }; |
| |
| /* |
| * Maximum block size used by the ZIL. This is picked up when the ZIL is |
| * initialized. Otherwise this should not be used directly; see |
| * zl_max_block_size instead. |
| */ |
| int zil_maxblocksize = SPA_OLD_MAXBLOCKSIZE; |
| |
| /* |
| * Start a log block write and advance to the next log block. |
| * Calls are serialized. |
| */ |
| static lwb_t * |
| zil_lwb_write_issue(zilog_t *zilog, lwb_t *lwb) |
| { |
| lwb_t *nlwb = NULL; |
| zil_chain_t *zilc; |
| spa_t *spa = zilog->zl_spa; |
| blkptr_t *bp; |
| dmu_tx_t *tx; |
| uint64_t txg; |
| uint64_t zil_blksz, wsz; |
| int i, error; |
| boolean_t slog; |
| |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| ASSERT3P(lwb->lwb_root_zio, !=, NULL); |
| ASSERT3P(lwb->lwb_write_zio, !=, NULL); |
| ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED); |
| |
| if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { |
| zilc = (zil_chain_t *)lwb->lwb_buf; |
| bp = &zilc->zc_next_blk; |
| } else { |
| zilc = (zil_chain_t *)(lwb->lwb_buf + lwb->lwb_sz); |
| bp = &zilc->zc_next_blk; |
| } |
| |
| ASSERT(lwb->lwb_nused <= lwb->lwb_sz); |
| |
| /* |
| * Allocate the next block and save its address in this block |
| * before writing it in order to establish the log chain. |
| * Note that if the allocation of nlwb synced before we wrote |
| * the block that points at it (lwb), we'd leak it if we crashed. |
| * Therefore, we don't do dmu_tx_commit() until zil_lwb_write_done(). |
| * We dirty the dataset to ensure that zil_sync() will be called |
| * to clean up in the event of allocation failure or I/O failure. |
| */ |
| |
| tx = dmu_tx_create(zilog->zl_os); |
| |
| /* |
| * Since we are not going to create any new dirty data, and we |
| * can even help with clearing the existing dirty data, we |
| * should not be subject to the dirty data based delays. We |
| * use TXG_NOTHROTTLE to bypass the delay mechanism. |
| */ |
| VERIFY0(dmu_tx_assign(tx, TXG_WAIT | TXG_NOTHROTTLE)); |
| |
| dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); |
| txg = dmu_tx_get_txg(tx); |
| |
| lwb->lwb_tx = tx; |
| |
| /* |
| * Log blocks are pre-allocated. Here we select the size of the next |
| * block, based on size used in the last block. |
| * - first find the smallest bucket that will fit the block from a |
| * limited set of block sizes. This is because it's faster to write |
| * blocks allocated from the same metaslab as they are adjacent or |
| * close. |
| * - next find the maximum from the new suggested size and an array of |
| * previous sizes. This lessens a picket fence effect of wrongly |
| * guessing the size if we have a stream of say 2k, 64k, 2k, 64k |
| * requests. |
| * |
| * Note we only write what is used, but we can't just allocate |
| * the maximum block size because we can exhaust the available |
| * pool log space. |
| */ |
| zil_blksz = zilog->zl_cur_used + sizeof (zil_chain_t); |
| for (i = 0; zil_blksz > zil_block_buckets[i].limit; i++) |
| continue; |
| zil_blksz = MIN(zil_block_buckets[i].blksz, zilog->zl_max_block_size); |
| zilog->zl_prev_blks[zilog->zl_prev_rotor] = zil_blksz; |
| for (i = 0; i < ZIL_PREV_BLKS; i++) |
| zil_blksz = MAX(zil_blksz, zilog->zl_prev_blks[i]); |
| zilog->zl_prev_rotor = (zilog->zl_prev_rotor + 1) & (ZIL_PREV_BLKS - 1); |
| |
| BP_ZERO(bp); |
| error = zio_alloc_zil(spa, zilog->zl_os, txg, bp, zil_blksz, &slog); |
| if (slog) { |
| ZIL_STAT_BUMP(zil_itx_metaslab_slog_count); |
| ZIL_STAT_INCR(zil_itx_metaslab_slog_bytes, lwb->lwb_nused); |
| } else { |
| ZIL_STAT_BUMP(zil_itx_metaslab_normal_count); |
| ZIL_STAT_INCR(zil_itx_metaslab_normal_bytes, lwb->lwb_nused); |
| } |
| if (error == 0) { |
| ASSERT3U(bp->blk_birth, ==, txg); |
| bp->blk_cksum = lwb->lwb_blk.blk_cksum; |
| bp->blk_cksum.zc_word[ZIL_ZC_SEQ]++; |
| |
| /* |
| * Allocate a new log write block (lwb). |
| */ |
| nlwb = zil_alloc_lwb(zilog, bp, slog, txg, TRUE); |
| } |
| |
| if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) { |
| /* For Slim ZIL only write what is used. */ |
| wsz = P2ROUNDUP_TYPED(lwb->lwb_nused, ZIL_MIN_BLKSZ, uint64_t); |
| ASSERT3U(wsz, <=, lwb->lwb_sz); |
| zio_shrink(lwb->lwb_write_zio, wsz); |
| |
| } else { |
| wsz = lwb->lwb_sz; |
| } |
| |
| zilc->zc_pad = 0; |
| zilc->zc_nused = lwb->lwb_nused; |
| zilc->zc_eck.zec_cksum = lwb->lwb_blk.blk_cksum; |
| |
| /* |
| * clear unused data for security |
| */ |
| bzero(lwb->lwb_buf + lwb->lwb_nused, wsz - lwb->lwb_nused); |
| |
| spa_config_enter(zilog->zl_spa, SCL_STATE, lwb, RW_READER); |
| |
| zil_lwb_add_block(lwb, &lwb->lwb_blk); |
| lwb->lwb_issued_timestamp = gethrtime(); |
| lwb->lwb_state = LWB_STATE_ISSUED; |
| |
| zio_nowait(lwb->lwb_root_zio); |
| zio_nowait(lwb->lwb_write_zio); |
| |
| /* |
| * If there was an allocation failure then nlwb will be null which |
| * forces a txg_wait_synced(). |
| */ |
| return (nlwb); |
| } |
| |
| /* |
| * Maximum amount of write data that can be put into single log block. |
| */ |
| uint64_t |
| zil_max_log_data(zilog_t *zilog) |
| { |
| return (zilog->zl_max_block_size - |
| sizeof (zil_chain_t) - sizeof (lr_write_t)); |
| } |
| |
| /* |
| * Maximum amount of log space we agree to waste to reduce number of |
| * WR_NEED_COPY chunks to reduce zl_get_data() overhead (~12%). |
| */ |
| static inline uint64_t |
| zil_max_waste_space(zilog_t *zilog) |
| { |
| return (zil_max_log_data(zilog) / 8); |
| } |
| |
| /* |
| * Maximum amount of write data for WR_COPIED. For correctness, consumers |
| * must fall back to WR_NEED_COPY if we can't fit the entire record into one |
| * maximum sized log block, because each WR_COPIED record must fit in a |
| * single log block. For space efficiency, we want to fit two records into a |
| * max-sized log block. |
| */ |
| uint64_t |
| zil_max_copied_data(zilog_t *zilog) |
| { |
| return ((zilog->zl_max_block_size - sizeof (zil_chain_t)) / 2 - |
| sizeof (lr_write_t)); |
| } |
| |
| static lwb_t * |
| zil_lwb_commit(zilog_t *zilog, itx_t *itx, lwb_t *lwb) |
| { |
| lr_t *lrcb, *lrc; |
| lr_write_t *lrwb, *lrw; |
| char *lr_buf; |
| uint64_t dlen, dnow, lwb_sp, reclen, txg, max_log_data; |
| |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| ASSERT3P(lwb, !=, NULL); |
| ASSERT3P(lwb->lwb_buf, !=, NULL); |
| |
| zil_lwb_write_open(zilog, lwb); |
| |
| lrc = &itx->itx_lr; |
| lrw = (lr_write_t *)lrc; |
| |
| /* |
| * A commit itx doesn't represent any on-disk state; instead |
| * it's simply used as a place holder on the commit list, and |
| * provides a mechanism for attaching a "commit waiter" onto the |
| * correct lwb (such that the waiter can be signalled upon |
| * completion of that lwb). Thus, we don't process this itx's |
| * log record if it's a commit itx (these itx's don't have log |
| * records), and instead link the itx's waiter onto the lwb's |
| * list of waiters. |
| * |
| * For more details, see the comment above zil_commit(). |
| */ |
| if (lrc->lrc_txtype == TX_COMMIT) { |
| mutex_enter(&zilog->zl_lock); |
| zil_commit_waiter_link_lwb(itx->itx_private, lwb); |
| itx->itx_private = NULL; |
| mutex_exit(&zilog->zl_lock); |
| return (lwb); |
| } |
| |
| if (lrc->lrc_txtype == TX_WRITE && itx->itx_wr_state == WR_NEED_COPY) { |
| dlen = P2ROUNDUP_TYPED( |
| lrw->lr_length, sizeof (uint64_t), uint64_t); |
| } else { |
| dlen = 0; |
| } |
| reclen = lrc->lrc_reclen; |
| zilog->zl_cur_used += (reclen + dlen); |
| txg = lrc->lrc_txg; |
| |
| ASSERT3U(zilog->zl_cur_used, <, UINT64_MAX - (reclen + dlen)); |
| |
| cont: |
| /* |
| * If this record won't fit in the current log block, start a new one. |
| * For WR_NEED_COPY optimize layout for minimal number of chunks. |
| */ |
| lwb_sp = lwb->lwb_sz - lwb->lwb_nused; |
| max_log_data = zil_max_log_data(zilog); |
| if (reclen > lwb_sp || (reclen + dlen > lwb_sp && |
| lwb_sp < zil_max_waste_space(zilog) && |
| (dlen % max_log_data == 0 || |
| lwb_sp < reclen + dlen % max_log_data))) { |
| lwb = zil_lwb_write_issue(zilog, lwb); |
| if (lwb == NULL) |
| return (NULL); |
| zil_lwb_write_open(zilog, lwb); |
| ASSERT(LWB_EMPTY(lwb)); |
| lwb_sp = lwb->lwb_sz - lwb->lwb_nused; |
| |
| /* |
| * There must be enough space in the new, empty log block to |
| * hold reclen. For WR_COPIED, we need to fit the whole |
| * record in one block, and reclen is the header size + the |
| * data size. For WR_NEED_COPY, we can create multiple |
| * records, splitting the data into multiple blocks, so we |
| * only need to fit one word of data per block; in this case |
| * reclen is just the header size (no data). |
| */ |
| ASSERT3U(reclen + MIN(dlen, sizeof (uint64_t)), <=, lwb_sp); |
| } |
| |
| dnow = MIN(dlen, lwb_sp - reclen); |
| lr_buf = lwb->lwb_buf + lwb->lwb_nused; |
| bcopy(lrc, lr_buf, reclen); |
| lrcb = (lr_t *)lr_buf; /* Like lrc, but inside lwb. */ |
| lrwb = (lr_write_t *)lrcb; /* Like lrw, but inside lwb. */ |
| |
| ZIL_STAT_BUMP(zil_itx_count); |
| |
| /* |
| * If it's a write, fetch the data or get its blkptr as appropriate. |
| */ |
| if (lrc->lrc_txtype == TX_WRITE) { |
| if (txg > spa_freeze_txg(zilog->zl_spa)) |
| txg_wait_synced(zilog->zl_dmu_pool, txg); |
| if (itx->itx_wr_state == WR_COPIED) { |
| ZIL_STAT_BUMP(zil_itx_copied_count); |
| ZIL_STAT_INCR(zil_itx_copied_bytes, lrw->lr_length); |
| } else { |
| char *dbuf; |
| int error; |
| |
| if (itx->itx_wr_state == WR_NEED_COPY) { |
| dbuf = lr_buf + reclen; |
| lrcb->lrc_reclen += dnow; |
| if (lrwb->lr_length > dnow) |
| lrwb->lr_length = dnow; |
| lrw->lr_offset += dnow; |
| lrw->lr_length -= dnow; |
| ZIL_STAT_BUMP(zil_itx_needcopy_count); |
| ZIL_STAT_INCR(zil_itx_needcopy_bytes, dnow); |
| } else { |
| ASSERT3S(itx->itx_wr_state, ==, WR_INDIRECT); |
| dbuf = NULL; |
| ZIL_STAT_BUMP(zil_itx_indirect_count); |
| ZIL_STAT_INCR(zil_itx_indirect_bytes, |
| lrw->lr_length); |
| } |
| |
| /* |
| * We pass in the "lwb_write_zio" rather than |
| * "lwb_root_zio" so that the "lwb_write_zio" |
| * becomes the parent of any zio's created by |
| * the "zl_get_data" callback. The vdevs are |
| * flushed after the "lwb_write_zio" completes, |
| * so we want to make sure that completion |
| * callback waits for these additional zio's, |
| * such that the vdevs used by those zio's will |
| * be included in the lwb's vdev tree, and those |
| * vdevs will be properly flushed. If we passed |
| * in "lwb_root_zio" here, then these additional |
| * vdevs may not be flushed; e.g. if these zio's |
| * completed after "lwb_write_zio" completed. |
| */ |
| error = zilog->zl_get_data(itx->itx_private, |
| lrwb, dbuf, lwb, lwb->lwb_write_zio); |
| |
| if (error == EIO) { |
| txg_wait_synced(zilog->zl_dmu_pool, txg); |
| return (lwb); |
| } |
| if (error != 0) { |
| ASSERT(error == ENOENT || error == EEXIST || |
| error == EALREADY); |
| return (lwb); |
| } |
| } |
| } |
| |
| /* |
| * We're actually making an entry, so update lrc_seq to be the |
| * log record sequence number. Note that this is generally not |
| * equal to the itx sequence number because not all transactions |
| * are synchronous, and sometimes spa_sync() gets there first. |
| */ |
| lrcb->lrc_seq = ++zilog->zl_lr_seq; |
| lwb->lwb_nused += reclen + dnow; |
| |
| zil_lwb_add_txg(lwb, txg); |
| |
| ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_sz); |
| ASSERT0(P2PHASE(lwb->lwb_nused, sizeof (uint64_t))); |
| |
| dlen -= dnow; |
| if (dlen > 0) { |
| zilog->zl_cur_used += reclen; |
| goto cont; |
| } |
| |
| return (lwb); |
| } |
| |
| itx_t * |
| zil_itx_create(uint64_t txtype, size_t lrsize) |
| { |
| size_t itxsize; |
| itx_t *itx; |
| |
| lrsize = P2ROUNDUP_TYPED(lrsize, sizeof (uint64_t), size_t); |
| itxsize = offsetof(itx_t, itx_lr) + lrsize; |
| |
| itx = zio_data_buf_alloc(itxsize); |
| itx->itx_lr.lrc_txtype = txtype; |
| itx->itx_lr.lrc_reclen = lrsize; |
| itx->itx_lr.lrc_seq = 0; /* defensive */ |
| itx->itx_sync = B_TRUE; /* default is synchronous */ |
| itx->itx_callback = NULL; |
| itx->itx_callback_data = NULL; |
| itx->itx_size = itxsize; |
| |
| return (itx); |
| } |
| |
| void |
| zil_itx_destroy(itx_t *itx) |
| { |
| IMPLY(itx->itx_lr.lrc_txtype == TX_COMMIT, itx->itx_callback == NULL); |
| IMPLY(itx->itx_callback != NULL, itx->itx_lr.lrc_txtype != TX_COMMIT); |
| |
| if (itx->itx_callback != NULL) |
| itx->itx_callback(itx->itx_callback_data); |
| |
| zio_data_buf_free(itx, itx->itx_size); |
| } |
| |
| /* |
| * Free up the sync and async itxs. The itxs_t has already been detached |
| * so no locks are needed. |
| */ |
| static void |
| zil_itxg_clean(itxs_t *itxs) |
| { |
| itx_t *itx; |
| list_t *list; |
| avl_tree_t *t; |
| void *cookie; |
| itx_async_node_t *ian; |
| |
| list = &itxs->i_sync_list; |
| while ((itx = list_head(list)) != NULL) { |
| /* |
| * In the general case, commit itxs will not be found |
| * here, as they'll be committed to an lwb via |
| * zil_lwb_commit(), and free'd in that function. Having |
| * said that, it is still possible for commit itxs to be |
| * found here, due to the following race: |
| * |
| * - a thread calls zil_commit() which assigns the |
| * commit itx to a per-txg i_sync_list |
| * - zil_itxg_clean() is called (e.g. via spa_sync()) |
| * while the waiter is still on the i_sync_list |
| * |
| * There's nothing to prevent syncing the txg while the |
| * waiter is on the i_sync_list. This normally doesn't |
| * happen because spa_sync() is slower than zil_commit(), |
| * but if zil_commit() calls txg_wait_synced() (e.g. |
| * because zil_create() or zil_commit_writer_stall() is |
| * called) we will hit this case. |
| */ |
| if (itx->itx_lr.lrc_txtype == TX_COMMIT) |
| zil_commit_waiter_skip(itx->itx_private); |
| |
| list_remove(list, itx); |
| zil_itx_destroy(itx); |
| } |
| |
| cookie = NULL; |
| t = &itxs->i_async_tree; |
| while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { |
| list = &ian->ia_list; |
| while ((itx = list_head(list)) != NULL) { |
| list_remove(list, itx); |
| /* commit itxs should never be on the async lists. */ |
| ASSERT3U(itx->itx_lr.lrc_txtype, !=, TX_COMMIT); |
| zil_itx_destroy(itx); |
| } |
| list_destroy(list); |
| kmem_free(ian, sizeof (itx_async_node_t)); |
| } |
| avl_destroy(t); |
| |
| kmem_free(itxs, sizeof (itxs_t)); |
| } |
| |
| static int |
| zil_aitx_compare(const void *x1, const void *x2) |
| { |
| const uint64_t o1 = ((itx_async_node_t *)x1)->ia_foid; |
| const uint64_t o2 = ((itx_async_node_t *)x2)->ia_foid; |
| |
| return (AVL_CMP(o1, o2)); |
| } |
| |
| /* |
| * Remove all async itx with the given oid. |
| */ |
| void |
| zil_remove_async(zilog_t *zilog, uint64_t oid) |
| { |
| uint64_t otxg, txg; |
| itx_async_node_t *ian; |
| avl_tree_t *t; |
| avl_index_t where; |
| list_t clean_list; |
| itx_t *itx; |
| |
| ASSERT(oid != 0); |
| list_create(&clean_list, sizeof (itx_t), offsetof(itx_t, itx_node)); |
| |
| if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ |
| otxg = ZILTEST_TXG; |
| else |
| otxg = spa_last_synced_txg(zilog->zl_spa) + 1; |
| |
| for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { |
| itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; |
| |
| mutex_enter(&itxg->itxg_lock); |
| if (itxg->itxg_txg != txg) { |
| mutex_exit(&itxg->itxg_lock); |
| continue; |
| } |
| |
| /* |
| * Locate the object node and append its list. |
| */ |
| t = &itxg->itxg_itxs->i_async_tree; |
| ian = avl_find(t, &oid, &where); |
| if (ian != NULL) |
| list_move_tail(&clean_list, &ian->ia_list); |
| mutex_exit(&itxg->itxg_lock); |
| } |
| while ((itx = list_head(&clean_list)) != NULL) { |
| list_remove(&clean_list, itx); |
| /* commit itxs should never be on the async lists. */ |
| ASSERT3U(itx->itx_lr.lrc_txtype, !=, TX_COMMIT); |
| zil_itx_destroy(itx); |
| } |
| list_destroy(&clean_list); |
| } |
| |
| void |
| zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx) |
| { |
| uint64_t txg; |
| itxg_t *itxg; |
| itxs_t *itxs, *clean = NULL; |
| |
| /* |
| * Ensure the data of a renamed file is committed before the rename. |
| */ |
| if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_RENAME) |
| zil_async_to_sync(zilog, itx->itx_oid); |
| |
| if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) |
| txg = ZILTEST_TXG; |
| else |
| txg = dmu_tx_get_txg(tx); |
| |
| itxg = &zilog->zl_itxg[txg & TXG_MASK]; |
| mutex_enter(&itxg->itxg_lock); |
| itxs = itxg->itxg_itxs; |
| if (itxg->itxg_txg != txg) { |
| if (itxs != NULL) { |
| /* |
| * The zil_clean callback hasn't got around to cleaning |
| * this itxg. Save the itxs for release below. |
| * This should be rare. |
| */ |
| zfs_dbgmsg("zil_itx_assign: missed itx cleanup for " |
| "txg %llu", itxg->itxg_txg); |
| clean = itxg->itxg_itxs; |
| } |
| itxg->itxg_txg = txg; |
| itxs = itxg->itxg_itxs = kmem_zalloc(sizeof (itxs_t), |
| KM_SLEEP); |
| |
| list_create(&itxs->i_sync_list, sizeof (itx_t), |
| offsetof(itx_t, itx_node)); |
| avl_create(&itxs->i_async_tree, zil_aitx_compare, |
| sizeof (itx_async_node_t), |
| offsetof(itx_async_node_t, ia_node)); |
| } |
| if (itx->itx_sync) { |
| list_insert_tail(&itxs->i_sync_list, itx); |
| } else { |
| avl_tree_t *t = &itxs->i_async_tree; |
| uint64_t foid = |
| LR_FOID_GET_OBJ(((lr_ooo_t *)&itx->itx_lr)->lr_foid); |
| itx_async_node_t *ian; |
| avl_index_t where; |
| |
| ian = avl_find(t, &foid, &where); |
| if (ian == NULL) { |
| ian = kmem_alloc(sizeof (itx_async_node_t), |
| KM_SLEEP); |
| list_create(&ian->ia_list, sizeof (itx_t), |
| offsetof(itx_t, itx_node)); |
| ian->ia_foid = foid; |
| avl_insert(t, ian, where); |
| } |
| list_insert_tail(&ian->ia_list, itx); |
| } |
| |
| itx->itx_lr.lrc_txg = dmu_tx_get_txg(tx); |
| |
| /* |
| * We don't want to dirty the ZIL using ZILTEST_TXG, because |
| * zil_clean() will never be called using ZILTEST_TXG. Thus, we |
| * need to be careful to always dirty the ZIL using the "real" |
| * TXG (not itxg_txg) even when the SPA is frozen. |
| */ |
| zilog_dirty(zilog, dmu_tx_get_txg(tx)); |
| mutex_exit(&itxg->itxg_lock); |
| |
| /* Release the old itxs now we've dropped the lock */ |
| if (clean != NULL) |
| zil_itxg_clean(clean); |
| } |
| |
| /* |
| * If there are any in-memory intent log transactions which have now been |
| * synced then start up a taskq to free them. We should only do this after we |
| * have written out the uberblocks (i.e. txg has been committed) so that |
| * don't inadvertently clean out in-memory log records that would be required |
| * by zil_commit(). |
| */ |
| void |
| zil_clean(zilog_t *zilog, uint64_t synced_txg) |
| { |
| itxg_t *itxg = &zilog->zl_itxg[synced_txg & TXG_MASK]; |
| itxs_t *clean_me; |
| |
| ASSERT3U(synced_txg, <, ZILTEST_TXG); |
| |
| mutex_enter(&itxg->itxg_lock); |
| if (itxg->itxg_itxs == NULL || itxg->itxg_txg == ZILTEST_TXG) { |
| mutex_exit(&itxg->itxg_lock); |
| return; |
| } |
| ASSERT3U(itxg->itxg_txg, <=, synced_txg); |
| ASSERT3U(itxg->itxg_txg, !=, 0); |
| clean_me = itxg->itxg_itxs; |
| itxg->itxg_itxs = NULL; |
| itxg->itxg_txg = 0; |
| mutex_exit(&itxg->itxg_lock); |
| /* |
| * Preferably start a task queue to free up the old itxs but |
| * if taskq_dispatch can't allocate resources to do that then |
| * free it in-line. This should be rare. Note, using TQ_SLEEP |
| * created a bad performance problem. |
| */ |
| ASSERT3P(zilog->zl_dmu_pool, !=, NULL); |
| ASSERT3P(zilog->zl_dmu_pool->dp_zil_clean_taskq, !=, NULL); |
| taskqid_t id = taskq_dispatch(zilog->zl_dmu_pool->dp_zil_clean_taskq, |
| (void (*)(void *))zil_itxg_clean, clean_me, TQ_NOSLEEP); |
| if (id == TASKQID_INVALID) |
| zil_itxg_clean(clean_me); |
| } |
| |
| /* |
| * This function will traverse the queue of itxs that need to be |
| * committed, and move them onto the ZIL's zl_itx_commit_list. |
| */ |
| static void |
| zil_get_commit_list(zilog_t *zilog) |
| { |
| uint64_t otxg, txg; |
| list_t *commit_list = &zilog->zl_itx_commit_list; |
| |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| |
| if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ |
| otxg = ZILTEST_TXG; |
| else |
| otxg = spa_last_synced_txg(zilog->zl_spa) + 1; |
| |
| /* |
| * This is inherently racy, since there is nothing to prevent |
| * the last synced txg from changing. That's okay since we'll |
| * only commit things in the future. |
| */ |
| for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { |
| itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; |
| |
| mutex_enter(&itxg->itxg_lock); |
| if (itxg->itxg_txg != txg) { |
| mutex_exit(&itxg->itxg_lock); |
| continue; |
| } |
| |
| /* |
| * If we're adding itx records to the zl_itx_commit_list, |
| * then the zil better be dirty in this "txg". We can assert |
| * that here since we're holding the itxg_lock which will |
| * prevent spa_sync from cleaning it. Once we add the itxs |
| * to the zl_itx_commit_list we must commit it to disk even |
| * if it's unnecessary (i.e. the txg was synced). |
| */ |
| ASSERT(zilog_is_dirty_in_txg(zilog, txg) || |
| spa_freeze_txg(zilog->zl_spa) != UINT64_MAX); |
| list_move_tail(commit_list, &itxg->itxg_itxs->i_sync_list); |
| |
| mutex_exit(&itxg->itxg_lock); |
| } |
| } |
| |
| /* |
| * Move the async itxs for a specified object to commit into sync lists. |
| */ |
| static void |
| zil_async_to_sync(zilog_t *zilog, uint64_t foid) |
| { |
| uint64_t otxg, txg; |
| itx_async_node_t *ian; |
| avl_tree_t *t; |
| avl_index_t where; |
| |
| if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */ |
| otxg = ZILTEST_TXG; |
| else |
| otxg = spa_last_synced_txg(zilog->zl_spa) + 1; |
| |
| /* |
| * This is inherently racy, since there is nothing to prevent |
| * the last synced txg from changing. |
| */ |
| for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) { |
| itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK]; |
| |
| mutex_enter(&itxg->itxg_lock); |
| if (itxg->itxg_txg != txg) { |
| mutex_exit(&itxg->itxg_lock); |
| continue; |
| } |
| |
| /* |
| * If a foid is specified then find that node and append its |
| * list. Otherwise walk the tree appending all the lists |
| * to the sync list. We add to the end rather than the |
| * beginning to ensure the create has happened. |
| */ |
| t = &itxg->itxg_itxs->i_async_tree; |
| if (foid != 0) { |
| ian = avl_find(t, &foid, &where); |
| if (ian != NULL) { |
| list_move_tail(&itxg->itxg_itxs->i_sync_list, |
| &ian->ia_list); |
| } |
| } else { |
| void *cookie = NULL; |
| |
| while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) { |
| list_move_tail(&itxg->itxg_itxs->i_sync_list, |
| &ian->ia_list); |
| list_destroy(&ian->ia_list); |
| kmem_free(ian, sizeof (itx_async_node_t)); |
| } |
| } |
| mutex_exit(&itxg->itxg_lock); |
| } |
| } |
| |
| /* |
| * This function will prune commit itxs that are at the head of the |
| * commit list (it won't prune past the first non-commit itx), and |
| * either: a) attach them to the last lwb that's still pending |
| * completion, or b) skip them altogether. |
| * |
| * This is used as a performance optimization to prevent commit itxs |
| * from generating new lwbs when it's unnecessary to do so. |
| */ |
| static void |
| zil_prune_commit_list(zilog_t *zilog) |
| { |
| itx_t *itx; |
| |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| |
| while ((itx = list_head(&zilog->zl_itx_commit_list)) != NULL) { |
| lr_t *lrc = &itx->itx_lr; |
| if (lrc->lrc_txtype != TX_COMMIT) |
| break; |
| |
| mutex_enter(&zilog->zl_lock); |
| |
| lwb_t *last_lwb = zilog->zl_last_lwb_opened; |
| if (last_lwb == NULL || |
| last_lwb->lwb_state == LWB_STATE_FLUSH_DONE) { |
| /* |
| * All of the itxs this waiter was waiting on |
| * must have already completed (or there were |
| * never any itx's for it to wait on), so it's |
| * safe to skip this waiter and mark it done. |
| */ |
| zil_commit_waiter_skip(itx->itx_private); |
| } else { |
| zil_commit_waiter_link_lwb(itx->itx_private, last_lwb); |
| itx->itx_private = NULL; |
| } |
| |
| mutex_exit(&zilog->zl_lock); |
| |
| list_remove(&zilog->zl_itx_commit_list, itx); |
| zil_itx_destroy(itx); |
| } |
| |
| IMPLY(itx != NULL, itx->itx_lr.lrc_txtype != TX_COMMIT); |
| } |
| |
| static void |
| zil_commit_writer_stall(zilog_t *zilog) |
| { |
| /* |
| * When zio_alloc_zil() fails to allocate the next lwb block on |
| * disk, we must call txg_wait_synced() to ensure all of the |
| * lwbs in the zilog's zl_lwb_list are synced and then freed (in |
| * zil_sync()), such that any subsequent ZIL writer (i.e. a call |
| * to zil_process_commit_list()) will have to call zil_create(), |
| * and start a new ZIL chain. |
| * |
| * Since zil_alloc_zil() failed, the lwb that was previously |
| * issued does not have a pointer to the "next" lwb on disk. |
| * Thus, if another ZIL writer thread was to allocate the "next" |
| * on-disk lwb, that block could be leaked in the event of a |
| * crash (because the previous lwb on-disk would not point to |
| * it). |
| * |
| * We must hold the zilog's zl_issuer_lock while we do this, to |
| * ensure no new threads enter zil_process_commit_list() until |
| * all lwb's in the zl_lwb_list have been synced and freed |
| * (which is achieved via the txg_wait_synced() call). |
| */ |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| txg_wait_synced(zilog->zl_dmu_pool, 0); |
| ASSERT3P(list_tail(&zilog->zl_lwb_list), ==, NULL); |
| } |
| |
| /* |
| * This function will traverse the commit list, creating new lwbs as |
| * needed, and committing the itxs from the commit list to these newly |
| * created lwbs. Additionally, as a new lwb is created, the previous |
| * lwb will be issued to the zio layer to be written to disk. |
| */ |
| static void |
| zil_process_commit_list(zilog_t *zilog) |
| { |
| spa_t *spa = zilog->zl_spa; |
| list_t nolwb_itxs; |
| list_t nolwb_waiters; |
| lwb_t *lwb; |
| itx_t *itx; |
| |
| ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); |
| |
| /* |
| * Return if there's nothing to commit before we dirty the fs by |
| * calling zil_create(). |
| */ |
| if (list_head(&zilog->zl_itx_commit_list) == NULL) |
| return; |
| |
| list_create(&nolwb_itxs, sizeof (itx_t), offsetof(itx_t, itx_node)); |
| list_create(&nolwb_waiters, sizeof (zil_commit_waiter_t), |
| offsetof(zil_commit_waiter_t, zcw_node)); |
| |
| lwb = list_tail(&zilog->zl_lwb_list); |
| if (lwb == NULL) { |
| lwb = zil_create(zilog); |
| } else { |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_ISSUED); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_WRITE_DONE); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_FLUSH_DONE); |
| } |
| |
| while ((itx = list_head(&zilog->zl_itx_commit_list)) != NULL) { |
| lr_t *lrc = &itx->itx_lr; |
| uint64_t txg = lrc->lrc_txg; |
| |
| ASSERT3U(txg, !=, 0); |
| |
| if (lrc->lrc_txtype == TX_COMMIT) { |
| DTRACE_PROBE2(zil__process__commit__itx, |
| zilog_t *, zilog, itx_t *, itx); |
| } else { |
| DTRACE_PROBE2(zil__process__normal__itx, |
| zilog_t *, zilog, itx_t *, itx); |
| } |
| |
| list_remove(&zilog->zl_itx_commit_list, itx); |
| |
| boolean_t synced = txg <= spa_last_synced_txg(spa); |
| boolean_t frozen = txg > spa_freeze_txg(spa); |
| |
| /* |
| * If the txg of this itx has already been synced out, then |
| * we don't need to commit this itx to an lwb. This is |
| * because the data of this itx will have already been |
| * written to the main pool. This is inherently racy, and |
| * it's still ok to commit an itx whose txg has already |
| * been synced; this will result in a write that's |
| * unnecessary, but will do no harm. |
| * |
| * With that said, we always want to commit TX_COMMIT itxs |
| * to an lwb, regardless of whether or not that itx's txg |
| * has been synced out. We do this to ensure any OPENED lwb |
| * will always have at least one zil_commit_waiter_t linked |
| * to the lwb. |
| * |
| * As a counter-example, if we skipped TX_COMMIT itx's |
| * whose txg had already been synced, the following |
| * situation could occur if we happened to be racing with |
| * spa_sync: |
| * |
| * 1. We commit a non-TX_COMMIT itx to an lwb, where the |
| * itx's txg is 10 and the last synced txg is 9. |
| * 2. spa_sync finishes syncing out txg 10. |
| * 3. We move to the next itx in the list, it's a TX_COMMIT |
| * whose txg is 10, so we skip it rather than committing |
| * it to the lwb used in (1). |
| * |
| * If the itx that is skipped in (3) is the last TX_COMMIT |
| * itx in the commit list, than it's possible for the lwb |
| * used in (1) to remain in the OPENED state indefinitely. |
| * |
| * To prevent the above scenario from occurring, ensuring |
| * that once an lwb is OPENED it will transition to ISSUED |
| * and eventually DONE, we always commit TX_COMMIT itx's to |
| * an lwb here, even if that itx's txg has already been |
| * synced. |
| * |
| * Finally, if the pool is frozen, we _always_ commit the |
| * itx. The point of freezing the pool is to prevent data |
| * from being written to the main pool via spa_sync, and |
| * instead rely solely on the ZIL to persistently store the |
| * data; i.e. when the pool is frozen, the last synced txg |
| * value can't be trusted. |
| */ |
| if (frozen || !synced || lrc->lrc_txtype == TX_COMMIT) { |
| if (lwb != NULL) { |
| lwb = zil_lwb_commit(zilog, itx, lwb); |
| |
| if (lwb == NULL) |
| list_insert_tail(&nolwb_itxs, itx); |
| else |
| list_insert_tail(&lwb->lwb_itxs, itx); |
| } else { |
| if (lrc->lrc_txtype == TX_COMMIT) { |
| zil_commit_waiter_link_nolwb( |
| itx->itx_private, &nolwb_waiters); |
| } |
| |
| list_insert_tail(&nolwb_itxs, itx); |
| } |
| } else { |
| ASSERT3S(lrc->lrc_txtype, !=, TX_COMMIT); |
| zil_itx_destroy(itx); |
| } |
| } |
| |
| if (lwb == NULL) { |
| /* |
| * This indicates zio_alloc_zil() failed to allocate the |
| * "next" lwb on-disk. When this happens, we must stall |
| * the ZIL write pipeline; see the comment within |
| * zil_commit_writer_stall() for more details. |
| */ |
| zil_commit_writer_stall(zilog); |
| |
| /* |
| * Additionally, we have to signal and mark the "nolwb" |
| * waiters as "done" here, since without an lwb, we |
| * can't do this via zil_lwb_flush_vdevs_done() like |
| * normal. |
| */ |
| zil_commit_waiter_t *zcw; |
| while ((zcw = list_head(&nolwb_waiters)) != NULL) { |
| zil_commit_waiter_skip(zcw); |
| list_remove(&nolwb_waiters, zcw); |
| } |
| |
| /* |
| * And finally, we have to destroy the itx's that |
| * couldn't be committed to an lwb; this will also call |
| * the itx's callback if one exists for the itx. |
| */ |
| while ((itx = list_head(&nolwb_itxs)) != NULL) { |
| list_remove(&nolwb_itxs, itx); |
| zil_itx_destroy(itx); |
| } |
| } else { |
| ASSERT(list_is_empty(&nolwb_waiters)); |
| ASSERT3P(lwb, !=, NULL); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_ISSUED); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_WRITE_DONE); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_FLUSH_DONE); |
| |
| /* |
| * At this point, the ZIL block pointed at by the "lwb" |
| * variable is in one of the following states: "closed" |
| * or "open". |
| * |
| * If it's "closed", then no itxs have been committed to |
| * it, so there's no point in issuing its zio (i.e. it's |
| * "empty"). |
| * |
| * If it's "open", then it contains one or more itxs that |
| * eventually need to be committed to stable storage. In |
| * this case we intentionally do not issue the lwb's zio |
| * to disk yet, and instead rely on one of the following |
| * two mechanisms for issuing the zio: |
| * |
| * 1. Ideally, there will be more ZIL activity occurring |
| * on the system, such that this function will be |
| * immediately called again (not necessarily by the same |
| * thread) and this lwb's zio will be issued via |
| * zil_lwb_commit(). This way, the lwb is guaranteed to |
| * be "full" when it is issued to disk, and we'll make |
| * use of the lwb's size the best we can. |
| * |
| * 2. If there isn't sufficient ZIL activity occurring on |
| * the system, such that this lwb's zio isn't issued via |
| * zil_lwb_commit(), zil_commit_waiter() will issue the |
| * lwb's zio. If this occurs, the lwb is not guaranteed |
| * to be "full" by the time its zio is issued, and means |
| * the size of the lwb was "too large" given the amount |
| * of ZIL activity occurring on the system at that time. |
| * |
| * We do this for a couple of reasons: |
| * |
| * 1. To try and reduce the number of IOPs needed to |
| * write the same number of itxs. If an lwb has space |
| * available in its buffer for more itxs, and more itxs |
| * will be committed relatively soon (relative to the |
| * latency of performing a write), then it's beneficial |
| * to wait for these "next" itxs. This way, more itxs |
| * can be committed to stable storage with fewer writes. |
| * |
| * 2. To try and use the largest lwb block size that the |
| * incoming rate of itxs can support. Again, this is to |
| * try and pack as many itxs into as few lwbs as |
| * possible, without significantly impacting the latency |
| * of each individual itx. |
| */ |
| } |
| } |
| |
| /* |
| * This function is responsible for ensuring the passed in commit waiter |
| * (and associated commit itx) is committed to an lwb. If the waiter is |
| * not already committed to an lwb, all itxs in the zilog's queue of |
| * itxs will be processed. The assumption is the passed in waiter's |
| * commit itx will found in the queue just like the other non-commit |
| * itxs, such that when the entire queue is processed, the waiter will |
| * have been committed to an lwb. |
| * |
| * The lwb associated with the passed in waiter is not guaranteed to |
| * have been issued by the time this function completes. If the lwb is |
| * not issued, we rely on future calls to zil_commit_writer() to issue |
| * the lwb, or the timeout mechanism found in zil_commit_waiter(). |
| */ |
| static void |
| zil_commit_writer(zilog_t *zilog, zil_commit_waiter_t *zcw) |
| { |
| ASSERT(!MUTEX_HELD(&zilog->zl_lock)); |
| ASSERT(spa_writeable(zilog->zl_spa)); |
| |
| mutex_enter(&zilog->zl_issuer_lock); |
| |
| if (zcw->zcw_lwb != NULL || zcw->zcw_done) { |
| /* |
| * It's possible that, while we were waiting to acquire |
| * the "zl_issuer_lock", another thread committed this |
| * waiter to an lwb. If that occurs, we bail out early, |
| * without processing any of the zilog's queue of itxs. |
| * |
| * On certain workloads and system configurations, the |
| * "zl_issuer_lock" can become highly contended. In an |
| * attempt to reduce this contention, we immediately drop |
| * the lock if the waiter has already been processed. |
| * |
| * We've measured this optimization to reduce CPU spent |
| * contending on this lock by up to 5%, using a system |
| * with 32 CPUs, low latency storage (~50 usec writes), |
| * and 1024 threads performing sync writes. |
| */ |
| goto out; |
| } |
| |
| ZIL_STAT_BUMP(zil_commit_writer_count); |
| |
| zil_get_commit_list(zilog); |
| zil_prune_commit_list(zilog); |
| zil_process_commit_list(zilog); |
| |
| out: |
| mutex_exit(&zilog->zl_issuer_lock); |
| } |
| |
| static void |
| zil_commit_waiter_timeout(zilog_t *zilog, zil_commit_waiter_t *zcw) |
| { |
| ASSERT(!MUTEX_HELD(&zilog->zl_issuer_lock)); |
| ASSERT(MUTEX_HELD(&zcw->zcw_lock)); |
| ASSERT3B(zcw->zcw_done, ==, B_FALSE); |
| |
| lwb_t *lwb = zcw->zcw_lwb; |
| ASSERT3P(lwb, !=, NULL); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_CLOSED); |
| |
| /* |
| * If the lwb has already been issued by another thread, we can |
| * immediately return since there's no work to be done (the |
| * point of this function is to issue the lwb). Additionally, we |
| * do this prior to acquiring the zl_issuer_lock, to avoid |
| * acquiring it when it's not necessary to do so. |
| */ |
| if (lwb->lwb_state == LWB_STATE_ISSUED || |
| lwb->lwb_state == LWB_STATE_WRITE_DONE || |
| lwb->lwb_state == LWB_STATE_FLUSH_DONE) |
| return; |
| |
| /* |
| * In order to call zil_lwb_write_issue() we must hold the |
| * zilog's "zl_issuer_lock". We can't simply acquire that lock, |
| * since we're already holding the commit waiter's "zcw_lock", |
| * and those two locks are acquired in the opposite order |
| * elsewhere. |
| */ |
| mutex_exit(&zcw->zcw_lock); |
| mutex_enter(&zilog->zl_issuer_lock); |
| mutex_enter(&zcw->zcw_lock); |
| |
| /* |
| * Since we just dropped and re-acquired the commit waiter's |
| * lock, we have to re-check to see if the waiter was marked |
| * "done" during that process. If the waiter was marked "done", |
| * the "lwb" pointer is no longer valid (it can be free'd after |
| * the waiter is marked "done"), so without this check we could |
| * wind up with a use-after-free error below. |
| */ |
| if (zcw->zcw_done) |
| goto out; |
| |
| ASSERT3P(lwb, ==, zcw->zcw_lwb); |
| |
| /* |
| * We've already checked this above, but since we hadn't acquired |
| * the zilog's zl_issuer_lock, we have to perform this check a |
| * second time while holding the lock. |
| * |
| * We don't need to hold the zl_lock since the lwb cannot transition |
| * from OPENED to ISSUED while we hold the zl_issuer_lock. The lwb |
| * _can_ transition from ISSUED to DONE, but it's OK to race with |
| * that transition since we treat the lwb the same, whether it's in |
| * the ISSUED or DONE states. |
| * |
| * The important thing, is we treat the lwb differently depending on |
| * if it's ISSUED or OPENED, and block any other threads that might |
| * attempt to issue this lwb. For that reason we hold the |
| * zl_issuer_lock when checking the lwb_state; we must not call |
| * zil_lwb_write_issue() if the lwb had already been issued. |
| * |
| * See the comment above the lwb_state_t structure definition for |
| * more details on the lwb states, and locking requirements. |
| */ |
| if (lwb->lwb_state == LWB_STATE_ISSUED || |
| lwb->lwb_state == LWB_STATE_WRITE_DONE || |
| lwb->lwb_state == LWB_STATE_FLUSH_DONE) |
| goto out; |
| |
| ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED); |
| |
| /* |
| * As described in the comments above zil_commit_waiter() and |
| * zil_process_commit_list(), we need to issue this lwb's zio |
| * since we've reached the commit waiter's timeout and it still |
| * hasn't been issued. |
| */ |
| lwb_t *nlwb = zil_lwb_write_issue(zilog, lwb); |
| |
| IMPLY(nlwb != NULL, lwb->lwb_state != LWB_STATE_OPENED); |
| |
| /* |
| * Since the lwb's zio hadn't been issued by the time this thread |
| * reached its timeout, we reset the zilog's "zl_cur_used" field |
| * to influence the zil block size selection algorithm. |
| * |
| * By having to issue the lwb's zio here, it means the size of the |
| * lwb was too large, given the incoming throughput of itxs. By |
| * setting "zl_cur_used" to zero, we communicate this fact to the |
| * block size selection algorithm, so it can take this information |
| * into account, and potentially select a smaller size for the |
| * next lwb block that is allocated. |
| */ |
| zilog->zl_cur_used = 0; |
| |
| if (nlwb == NULL) { |
| /* |
| * When zil_lwb_write_issue() returns NULL, this |
| * indicates zio_alloc_zil() failed to allocate the |
| * "next" lwb on-disk. When this occurs, the ZIL write |
| * pipeline must be stalled; see the comment within the |
| * zil_commit_writer_stall() function for more details. |
| * |
| * We must drop the commit waiter's lock prior to |
| * calling zil_commit_writer_stall() or else we can wind |
| * up with the following deadlock: |
| * |
| * - This thread is waiting for the txg to sync while |
| * holding the waiter's lock; txg_wait_synced() is |
| * used within txg_commit_writer_stall(). |
| * |
| * - The txg can't sync because it is waiting for this |
| * lwb's zio callback to call dmu_tx_commit(). |
| * |
| * - The lwb's zio callback can't call dmu_tx_commit() |
| * because it's blocked trying to acquire the waiter's |
| * lock, which occurs prior to calling dmu_tx_commit() |
| */ |
| mutex_exit(&zcw->zcw_lock); |
| zil_commit_writer_stall(zilog); |
| mutex_enter(&zcw->zcw_lock); |
| } |
| |
| out: |
| mutex_exit(&zilog->zl_issuer_lock); |
| ASSERT(MUTEX_HELD(&zcw->zcw_lock)); |
| } |
| |
| /* |
| * This function is responsible for performing the following two tasks: |
| * |
| * 1. its primary responsibility is to block until the given "commit |
| * waiter" is considered "done". |
| * |
| * 2. its secondary responsibility is to issue the zio for the lwb that |
| * the given "commit waiter" is waiting on, if this function has |
| * waited "long enough" and the lwb is still in the "open" state. |
| * |
| * Given a sufficient amount of itxs being generated and written using |
| * the ZIL, the lwb's zio will be issued via the zil_lwb_commit() |
| * function. If this does not occur, this secondary responsibility will |
| * ensure the lwb is issued even if there is not other synchronous |
| * activity on the system. |
| * |
| * For more details, see zil_process_commit_list(); more specifically, |
| * the comment at the bottom of that function. |
| */ |
| static void |
| zil_commit_waiter(zilog_t *zilog, zil_commit_waiter_t *zcw) |
| { |
| ASSERT(!MUTEX_HELD(&zilog->zl_lock)); |
| ASSERT(!MUTEX_HELD(&zilog->zl_issuer_lock)); |
| ASSERT(spa_writeable(zilog->zl_spa)); |
| |
| mutex_enter(&zcw->zcw_lock); |
| |
| /* |
| * The timeout is scaled based on the lwb latency to avoid |
| * significantly impacting the latency of each individual itx. |
| * For more details, see the comment at the bottom of the |
| * zil_process_commit_list() function. |
| */ |
| int pct = MAX(zfs_commit_timeout_pct, 1); |
| hrtime_t sleep = (zilog->zl_last_lwb_latency * pct) / 100; |
| hrtime_t wakeup = gethrtime() + sleep; |
| boolean_t timedout = B_FALSE; |
| |
| while (!zcw->zcw_done) { |
| ASSERT(MUTEX_HELD(&zcw->zcw_lock)); |
| |
| lwb_t *lwb = zcw->zcw_lwb; |
| |
| /* |
| * Usually, the waiter will have a non-NULL lwb field here, |
| * but it's possible for it to be NULL as a result of |
| * zil_commit() racing with spa_sync(). |
| * |
| * When zil_clean() is called, it's possible for the itxg |
| * list (which may be cleaned via a taskq) to contain |
| * commit itxs. When this occurs, the commit waiters linked |
| * off of these commit itxs will not be committed to an |
| * lwb. Additionally, these commit waiters will not be |
| * marked done until zil_commit_waiter_skip() is called via |
| * zil_itxg_clean(). |
| * |
| * Thus, it's possible for this commit waiter (i.e. the |
| * "zcw" variable) to be found in this "in between" state; |
| * where it's "zcw_lwb" field is NULL, and it hasn't yet |
| * been skipped, so it's "zcw_done" field is still B_FALSE. |
| */ |
| IMPLY(lwb != NULL, lwb->lwb_state != LWB_STATE_CLOSED); |
| |
| if (lwb != NULL && lwb->lwb_state == LWB_STATE_OPENED) { |
| ASSERT3B(timedout, ==, B_FALSE); |
| |
| /* |
| * If the lwb hasn't been issued yet, then we |
| * need to wait with a timeout, in case this |
| * function needs to issue the lwb after the |
| * timeout is reached; responsibility (2) from |
| * the comment above this function. |
| */ |
| clock_t timeleft = cv_timedwait_hires(&zcw->zcw_cv, |
| &zcw->zcw_lock, wakeup, USEC2NSEC(1), |
| CALLOUT_FLAG_ABSOLUTE); |
| |
| if (timeleft >= 0 || zcw->zcw_done) |
| continue; |
| |
| timedout = B_TRUE; |
| zil_commit_waiter_timeout(zilog, zcw); |
| |
| if (!zcw->zcw_done) { |
| /* |
| * If the commit waiter has already been |
| * marked "done", it's possible for the |
| * waiter's lwb structure to have already |
| * been freed. Thus, we can only reliably |
| * make these assertions if the waiter |
| * isn't done. |
| */ |
| ASSERT3P(lwb, ==, zcw->zcw_lwb); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_OPENED); |
| } |
| } else { |
| /* |
| * If the lwb isn't open, then it must have already |
| * been issued. In that case, there's no need to |
| * use a timeout when waiting for the lwb to |
| * complete. |
| * |
| * Additionally, if the lwb is NULL, the waiter |
| * will soon be signaled and marked done via |
| * zil_clean() and zil_itxg_clean(), so no timeout |
| * is required. |
| */ |
| |
| IMPLY(lwb != NULL, |
| lwb->lwb_state == LWB_STATE_ISSUED || |
| lwb->lwb_state == LWB_STATE_WRITE_DONE || |
| lwb->lwb_state == LWB_STATE_FLUSH_DONE); |
| cv_wait(&zcw->zcw_cv, &zcw->zcw_lock); |
| } |
| } |
| |
| mutex_exit(&zcw->zcw_lock); |
| } |
| |
| static zil_commit_waiter_t * |
| zil_alloc_commit_waiter(void) |
| { |
| zil_commit_waiter_t *zcw = kmem_cache_alloc(zil_zcw_cache, KM_SLEEP); |
| |
| cv_init(&zcw->zcw_cv, NULL, CV_DEFAULT, NULL); |
| mutex_init(&zcw->zcw_lock, NULL, MUTEX_DEFAULT, NULL); |
| list_link_init(&zcw->zcw_node); |
| zcw->zcw_lwb = NULL; |
| zcw->zcw_done = B_FALSE; |
| zcw->zcw_zio_error = 0; |
| |
| return (zcw); |
| } |
| |
| static void |
| zil_free_commit_waiter(zil_commit_waiter_t *zcw) |
| { |
| ASSERT(!list_link_active(&zcw->zcw_node)); |
| ASSERT3P(zcw->zcw_lwb, ==, NULL); |
| ASSERT3B(zcw->zcw_done, ==, B_TRUE); |
| mutex_destroy(&zcw->zcw_lock); |
| cv_destroy(&zcw->zcw_cv); |
| kmem_cache_free(zil_zcw_cache, zcw); |
| } |
| |
| /* |
| * This function is used to create a TX_COMMIT itx and assign it. This |
| * way, it will be linked into the ZIL's list of synchronous itxs, and |
| * then later committed to an lwb (or skipped) when |
| * zil_process_commit_list() is called. |
| */ |
| static void |
| zil_commit_itx_assign(zilog_t *zilog, zil_commit_waiter_t *zcw) |
| { |
| dmu_tx_t *tx = dmu_tx_create(zilog->zl_os); |
| VERIFY0(dmu_tx_assign(tx, TXG_WAIT)); |
| |
| itx_t *itx = zil_itx_create(TX_COMMIT, sizeof (lr_t)); |
| itx->itx_sync = B_TRUE; |
| itx->itx_private = zcw; |
| |
| zil_itx_assign(zilog, itx, tx); |
| |
| dmu_tx_commit(tx); |
| } |
| |
| /* |
| * Commit ZFS Intent Log transactions (itxs) to stable storage. |
| * |
| * When writing ZIL transactions to the on-disk representation of the |
| * ZIL, the itxs are committed to a Log Write Block (lwb). Multiple |
| * itxs can be committed to a single lwb. Once a lwb is written and |
| * committed to stable storage (i.e. the lwb is written, and vdevs have |
| * been flushed), each itx that was committed to that lwb is also |
| * considered to be committed to stable storage. |
| * |
| * When an itx is committed to an lwb, the log record (lr_t) contained |
| * by the itx is copied into the lwb's zio buffer, and once this buffer |
| * is written to disk, it becomes an on-disk ZIL block. |
| * |
| * As itxs are generated, they're inserted into the ZIL's queue of |
| * uncommitted itxs. The semantics of zil_commit() are such that it will |
| * block until all itxs that were in the queue when it was called, are |
| * committed to stable storage. |
| * |
| * If "foid" is zero, this means all "synchronous" and "asynchronous" |
| * itxs, for all objects in the dataset, will be committed to stable |
| * storage prior to zil_commit() returning. If "foid" is non-zero, all |
| * "synchronous" itxs for all objects, but only "asynchronous" itxs |
| * that correspond to the foid passed in, will be committed to stable |
| * storage prior to zil_commit() returning. |
| * |
| * Generally speaking, when zil_commit() is called, the consumer doesn't |
| * actually care about _all_ of the uncommitted itxs. Instead, they're |
| * simply trying to waiting for a specific itx to be committed to disk, |
| * but the interface(s) for interacting with the ZIL don't allow such |
| * fine-grained communication. A better interface would allow a consumer |
| * to create and assign an itx, and then pass a reference to this itx to |
| * zil_commit(); such that zil_commit() would return as soon as that |
| * specific itx was committed to disk (instead of waiting for _all_ |
| * itxs to be committed). |
| * |
| * When a thread calls zil_commit() a special "commit itx" will be |
| * generated, along with a corresponding "waiter" for this commit itx. |
| * zil_commit() will wait on this waiter's CV, such that when the waiter |
| * is marked done, and signaled, zil_commit() will return. |
| * |
| * This commit itx is inserted into the queue of uncommitted itxs. This |
| * provides an easy mechanism for determining which itxs were in the |
| * queue prior to zil_commit() having been called, and which itxs were |
| * added after zil_commit() was called. |
| * |
| * The commit it is special; it doesn't have any on-disk representation. |
| * When a commit itx is "committed" to an lwb, the waiter associated |
| * with it is linked onto the lwb's list of waiters. Then, when that lwb |
| * completes, each waiter on the lwb's list is marked done and signaled |
| * -- allowing the thread waiting on the waiter to return from zil_commit(). |
| * |
| * It's important to point out a few critical factors that allow us |
| * to make use of the commit itxs, commit waiters, per-lwb lists of |
| * commit waiters, and zio completion callbacks like we're doing: |
| * |
| * 1. The list of waiters for each lwb is traversed, and each commit |
| * waiter is marked "done" and signaled, in the zio completion |
| * callback of the lwb's zio[*]. |
| * |
| * * Actually, the waiters are signaled in the zio completion |
| * callback of the root zio for the DKIOCFLUSHWRITECACHE commands |
| * that are sent to the vdevs upon completion of the lwb zio. |
| * |
| * 2. When the itxs are inserted into the ZIL's queue of uncommitted |
| * itxs, the order in which they are inserted is preserved[*]; as |
| * itxs are added to the queue, they are added to the tail of |
| * in-memory linked lists. |
| * |
| * When committing the itxs to lwbs (to be written to disk), they |
| * are committed in the same order in which the itxs were added to |
| * the uncommitted queue's linked list(s); i.e. the linked list of |
| * itxs to commit is traversed from head to tail, and each itx is |
| * committed to an lwb in that order. |
| * |
| * * To clarify: |
| * |
| * - the order of "sync" itxs is preserved w.r.t. other |
| * "sync" itxs, regardless of the corresponding objects. |
| * - the order of "async" itxs is preserved w.r.t. other |
| * "async" itxs corresponding to the same object. |
| * - the order of "async" itxs is *not* preserved w.r.t. other |
| * "async" itxs corresponding to different objects. |
| * - the order of "sync" itxs w.r.t. "async" itxs (or vice |
| * versa) is *not* preserved, even for itxs that correspond |
| * to the same object. |
| * |
| * For more details, see: zil_itx_assign(), zil_async_to_sync(), |
| * zil_get_commit_list(), and zil_process_commit_list(). |
| * |
| * 3. The lwbs represent a linked list of blocks on disk. Thus, any |
| * lwb cannot be considered committed to stable storage, until its |
| * "previous" lwb is also committed to stable storage. This fact, |
| * coupled with the fact described above, means that itxs are |
| * committed in (roughly) the order in which they were generated. |
| * This is essential because itxs are dependent on prior itxs. |
| * Thus, we *must not* deem an itx as being committed to stable |
| * storage, until *all* prior itxs have also been committed to |
| * stable storage. |
| * |
| * To enforce this ordering of lwb zio's, while still leveraging as |
| * much of the underlying storage performance as possible, we rely |
| * on two fundamental concepts: |
| * |
| * 1. The creation and issuance of lwb zio's is protected by |
| * the zilog's "zl_issuer_lock", which ensures only a single |
| * thread is creating and/or issuing lwb's at a time |
| * 2. The "previous" lwb is a child of the "current" lwb |
| * (leveraging the zio parent-child dependency graph) |
| * |
| * By relying on this parent-child zio relationship, we can have |
| * many lwb zio's concurrently issued to the underlying storage, |
| * but the order in which they complete will be the same order in |
| * which they were created. |
| */ |
| void |
| zil_commit(zilog_t *zilog, uint64_t foid) |
| { |
| /* |
| * We should never attempt to call zil_commit on a snapshot for |
| * a couple of reasons: |
| * |
| * 1. A snapshot may never be modified, thus it cannot have any |
| * in-flight itxs that would have modified the dataset. |
| * |
| * 2. By design, when zil_commit() is called, a commit itx will |
| * be assigned to this zilog; as a result, the zilog will be |
| * dirtied. We must not dirty the zilog of a snapshot; there's |
| * checks in the code that enforce this invariant, and will |
| * cause a panic if it's not upheld. |
| */ |
| ASSERT3B(dmu_objset_is_snapshot(zilog->zl_os), ==, B_FALSE); |
| |
| if (zilog->zl_sync == ZFS_SYNC_DISABLED) |
| return; |
| |
| if (!spa_writeable(zilog->zl_spa)) { |
| /* |
| * If the SPA is not writable, there should never be any |
| * pending itxs waiting to be committed to disk. If that |
| * weren't true, we'd skip writing those itxs out, and |
| * would break the semantics of zil_commit(); thus, we're |
| * verifying that truth before we return to the caller. |
| */ |
| ASSERT(list_is_empty(&zilog->zl_lwb_list)); |
| ASSERT3P(zilog->zl_last_lwb_opened, ==, NULL); |
| for (int i = 0; i < TXG_SIZE; i++) |
| ASSERT3P(zilog->zl_itxg[i].itxg_itxs, ==, NULL); |
| return; |
| } |
| |
| /* |
| * If the ZIL is suspended, we don't want to dirty it by calling |
| * zil_commit_itx_assign() below, nor can we write out |
| * lwbs like would be done in zil_commit_write(). Thus, we |
| * simply rely on txg_wait_synced() to maintain the necessary |
| * semantics, and avoid calling those functions altogether. |
| */ |
| if (zilog->zl_suspend > 0) { |
| txg_wait_synced(zilog->zl_dmu_pool, 0); |
| return; |
| } |
| |
| zil_commit_impl(zilog, foid); |
| } |
| |
| void |
| zil_commit_impl(zilog_t *zilog, uint64_t foid) |
| { |
| ZIL_STAT_BUMP(zil_commit_count); |
| |
| /* |
| * Move the "async" itxs for the specified foid to the "sync" |
| * queues, such that they will be later committed (or skipped) |
| * to an lwb when zil_process_commit_list() is called. |
| * |
| * Since these "async" itxs must be committed prior to this |
| * call to zil_commit returning, we must perform this operation |
| * before we call zil_commit_itx_assign(). |
| */ |
| zil_async_to_sync(zilog, foid); |
| |
| /* |
| * We allocate a new "waiter" structure which will initially be |
| * linked to the commit itx using the itx's "itx_private" field. |
| * Since the commit itx doesn't represent any on-disk state, |
| * when it's committed to an lwb, rather than copying the its |
| * lr_t into the lwb's buffer, the commit itx's "waiter" will be |
| * added to the lwb's list of waiters. Then, when the lwb is |
| * committed to stable storage, each waiter in the lwb's list of |
| * waiters will be marked "done", and signalled. |
| * |
| * We must create the waiter and assign the commit itx prior to |
| * calling zil_commit_writer(), or else our specific commit itx |
| * is not guaranteed to be committed to an lwb prior to calling |
| * zil_commit_waiter(). |
| */ |
| zil_commit_waiter_t *zcw = zil_alloc_commit_waiter(); |
| zil_commit_itx_assign(zilog, zcw); |
| |
| zil_commit_writer(zilog, zcw); |
| zil_commit_waiter(zilog, zcw); |
| |
| if (zcw->zcw_zio_error != 0) { |
| /* |
| * If there was an error writing out the ZIL blocks that |
| * this thread is waiting on, then we fallback to |
| * relying on spa_sync() to write out the data this |
| * thread is waiting on. Obviously this has performance |
| * implications, but the expectation is for this to be |
| * an exceptional case, and shouldn't occur often. |
| */ |
| DTRACE_PROBE2(zil__commit__io__error, |
| zilog_t *, zilog, zil_commit_waiter_t *, zcw); |
| txg_wait_synced(zilog->zl_dmu_pool, 0); |
| } |
| |
| zil_free_commit_waiter(zcw); |
| } |
| |
| /* |
| * Called in syncing context to free committed log blocks and update log header. |
| */ |
| void |
| zil_sync(zilog_t *zilog, dmu_tx_t *tx) |
| { |
| zil_header_t *zh = zil_header_in_syncing_context(zilog); |
| uint64_t txg = dmu_tx_get_txg(tx); |
| spa_t *spa = zilog->zl_spa; |
| uint64_t *replayed_seq = &zilog->zl_replayed_seq[txg & TXG_MASK]; |
| lwb_t *lwb; |
| |
| /* |
| * We don't zero out zl_destroy_txg, so make sure we don't try |
| * to destroy it twice. |
| */ |
| if (spa_sync_pass(spa) != 1) |
| return; |
| |
| mutex_enter(&zilog->zl_lock); |
| |
| ASSERT(zilog->zl_stop_sync == 0); |
| |
| if (*replayed_seq != 0) { |
| ASSERT(zh->zh_replay_seq < *replayed_seq); |
| zh->zh_replay_seq = *replayed_seq; |
| *replayed_seq = 0; |
| } |
| |
| if (zilog->zl_destroy_txg == txg) { |
| blkptr_t blk = zh->zh_log; |
| |
| ASSERT(list_head(&zilog->zl_lwb_list) == NULL); |
| |
| bzero(zh, sizeof (zil_header_t)); |
| bzero(zilog->zl_replayed_seq, sizeof (zilog->zl_replayed_seq)); |
| |
| if (zilog->zl_keep_first) { |
| /* |
| * If this block was part of log chain that couldn't |
| * be claimed because a device was missing during |
| * zil_claim(), but that device later returns, |
| * then this block could erroneously appear valid. |
| * To guard against this, assign a new GUID to the new |
| * log chain so it doesn't matter what blk points to. |
| */ |
| zil_init_log_chain(zilog, &blk); |
| zh->zh_log = blk; |
| } |
| } |
| |
| while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { |
| zh->zh_log = lwb->lwb_blk; |
| if (lwb->lwb_buf != NULL || lwb->lwb_max_txg > txg) |
| break; |
| list_remove(&zilog->zl_lwb_list, lwb); |
| zio_free(spa, txg, &lwb->lwb_blk); |
| zil_free_lwb(zilog, lwb); |
| |
| /* |
| * If we don't have anything left in the lwb list then |
| * we've had an allocation failure and we need to zero |
| * out the zil_header blkptr so that we don't end |
| * up freeing the same block twice. |
| */ |
| if (list_head(&zilog->zl_lwb_list) == NULL) |
| BP_ZERO(&zh->zh_log); |
| } |
| |
| /* |
| * Remove fastwrite on any blocks that have been pre-allocated for |
| * the next commit. This prevents fastwrite counter pollution by |
| * unused, long-lived LWBs. |
| */ |
| for (; lwb != NULL; lwb = list_next(&zilog->zl_lwb_list, lwb)) { |
| if (lwb->lwb_fastwrite && !lwb->lwb_write_zio) { |
| metaslab_fastwrite_unmark(zilog->zl_spa, &lwb->lwb_blk); |
| lwb->lwb_fastwrite = 0; |
| } |
| } |
| |
| mutex_exit(&zilog->zl_lock); |
| } |
| |
| /* ARGSUSED */ |
| static int |
| zil_lwb_cons(void *vbuf, void *unused, int kmflag) |
| { |
| lwb_t *lwb = vbuf; |
| list_create(&lwb->lwb_itxs, sizeof (itx_t), offsetof(itx_t, itx_node)); |
| list_create(&lwb->lwb_waiters, sizeof (zil_commit_waiter_t), |
| offsetof(zil_commit_waiter_t, zcw_node)); |
| avl_create(&lwb->lwb_vdev_tree, zil_lwb_vdev_compare, |
| sizeof (zil_vdev_node_t), offsetof(zil_vdev_node_t, zv_node)); |
| mutex_init(&lwb->lwb_vdev_lock, NULL, MUTEX_DEFAULT, NULL); |
| return (0); |
| } |
| |
| /* ARGSUSED */ |
| static void |
| zil_lwb_dest(void *vbuf, void *unused) |
| { |
| lwb_t *lwb = vbuf; |
| mutex_destroy(&lwb->lwb_vdev_lock); |
| avl_destroy(&lwb->lwb_vdev_tree); |
| list_destroy(&lwb->lwb_waiters); |
| list_destroy(&lwb->lwb_itxs); |
| } |
| |
| void |
| zil_init(void) |
| { |
| zil_lwb_cache = kmem_cache_create("zil_lwb_cache", |
| sizeof (lwb_t), 0, zil_lwb_cons, zil_lwb_dest, NULL, NULL, NULL, 0); |
| |
| zil_zcw_cache = kmem_cache_create("zil_zcw_cache", |
| sizeof (zil_commit_waiter_t), 0, NULL, NULL, NULL, NULL, NULL, 0); |
| |
| zil_ksp = kstat_create("zfs", 0, "zil", "misc", |
| KSTAT_TYPE_NAMED, sizeof (zil_stats) / sizeof (kstat_named_t), |
| KSTAT_FLAG_VIRTUAL); |
| |
| if (zil_ksp != NULL) { |
| zil_ksp->ks_data = &zil_stats; |
| kstat_install(zil_ksp); |
| } |
| } |
| |
| void |
| zil_fini(void) |
| { |
| kmem_cache_destroy(zil_zcw_cache); |
| kmem_cache_destroy(zil_lwb_cache); |
| |
| if (zil_ksp != NULL) { |
| kstat_delete(zil_ksp); |
| zil_ksp = NULL; |
| } |
| } |
| |
| void |
| zil_set_sync(zilog_t *zilog, uint64_t sync) |
| { |
| zilog->zl_sync = sync; |
| } |
| |
| void |
| zil_set_logbias(zilog_t *zilog, uint64_t logbias) |
| { |
| zilog->zl_logbias = logbias; |
| } |
| |
| zilog_t * |
| zil_alloc(objset_t *os, zil_header_t *zh_phys) |
| { |
| zilog_t *zilog; |
| |
| zilog = kmem_zalloc(sizeof (zilog_t), KM_SLEEP); |
| |
| zilog->zl_header = zh_phys; |
| zilog->zl_os = os; |
| zilog->zl_spa = dmu_objset_spa(os); |
| zilog->zl_dmu_pool = dmu_objset_pool(os); |
| zilog->zl_destroy_txg = TXG_INITIAL - 1; |
| zilog->zl_logbias = dmu_objset_logbias(os); |
| zilog->zl_sync = dmu_objset_syncprop(os); |
| zilog->zl_dirty_max_txg = 0; |
| zilog->zl_last_lwb_opened = NULL; |
| zilog->zl_last_lwb_latency = 0; |
| zilog->zl_max_block_size = zil_maxblocksize; |
| |
| mutex_init(&zilog->zl_lock, NULL, MUTEX_DEFAULT, NULL); |
| mutex_init(&zilog->zl_issuer_lock, NULL, MUTEX_DEFAULT, NULL); |
| |
| for (int i = 0; i < TXG_SIZE; i++) { |
| mutex_init(&zilog->zl_itxg[i].itxg_lock, NULL, |
| MUTEX_DEFAULT, NULL); |
| } |
| |
| list_create(&zilog->zl_lwb_list, sizeof (lwb_t), |
| offsetof(lwb_t, lwb_node)); |
| |
| list_create(&zilog->zl_itx_commit_list, sizeof (itx_t), |
| offsetof(itx_t, itx_node)); |
| |
| cv_init(&zilog->zl_cv_suspend, NULL, CV_DEFAULT, NULL); |
| |
| return (zilog); |
| } |
| |
| void |
| zil_free(zilog_t *zilog) |
| { |
| int i; |
| |
| zilog->zl_stop_sync = 1; |
| |
| ASSERT0(zilog->zl_suspend); |
| ASSERT0(zilog->zl_suspending); |
| |
| ASSERT(list_is_empty(&zilog->zl_lwb_list)); |
| list_destroy(&zilog->zl_lwb_list); |
| |
| ASSERT(list_is_empty(&zilog->zl_itx_commit_list)); |
| list_destroy(&zilog->zl_itx_commit_list); |
| |
| for (i = 0; i < TXG_SIZE; i++) { |
| /* |
| * It's possible for an itx to be generated that doesn't dirty |
| * a txg (e.g. ztest TX_TRUNCATE). So there's no zil_clean() |
| * callback to remove the entry. We remove those here. |
| * |
| * Also free up the ziltest itxs. |
| */ |
| if (zilog->zl_itxg[i].itxg_itxs) |
| zil_itxg_clean(zilog->zl_itxg[i].itxg_itxs); |
| mutex_destroy(&zilog->zl_itxg[i].itxg_lock); |
| } |
| |
| mutex_destroy(&zilog->zl_issuer_lock); |
| mutex_destroy(&zilog->zl_lock); |
| |
| cv_destroy(&zilog->zl_cv_suspend); |
| |
| kmem_free(zilog, sizeof (zilog_t)); |
| } |
| |
| /* |
| * Open an intent log. |
| */ |
| zilog_t * |
| zil_open(objset_t *os, zil_get_data_t *get_data) |
| { |
| zilog_t *zilog = dmu_objset_zil(os); |
| |
| ASSERT3P(zilog->zl_get_data, ==, NULL); |
| ASSERT3P(zilog->zl_last_lwb_opened, ==, NULL); |
| ASSERT(list_is_empty(&zilog->zl_lwb_list)); |
| |
| zilog->zl_get_data = get_data; |
| |
| return (zilog); |
| } |
| |
| /* |
| * Close an intent log. |
| */ |
| void |
| zil_close(zilog_t *zilog) |
| { |
| lwb_t *lwb; |
| uint64_t txg; |
| |
| if (!dmu_objset_is_snapshot(zilog->zl_os)) { |
| zil_commit(zilog, 0); |
| } else { |
| ASSERT3P(list_tail(&zilog->zl_lwb_list), ==, NULL); |
| ASSERT0(zilog->zl_dirty_max_txg); |
| ASSERT3B(zilog_is_dirty(zilog), ==, B_FALSE); |
| } |
| |
| mutex_enter(&zilog->zl_lock); |
| lwb = list_tail(&zilog->zl_lwb_list); |
| if (lwb == NULL) |
| txg = zilog->zl_dirty_max_txg; |
| else |
| txg = MAX(zilog->zl_dirty_max_txg, lwb->lwb_max_txg); |
| mutex_exit(&zilog->zl_lock); |
| |
| /* |
| * We need to use txg_wait_synced() to wait long enough for the |
| * ZIL to be clean, and to wait for all pending lwbs to be |
| * written out. |
| */ |
| if (txg != 0) |
| txg_wait_synced(zilog->zl_dmu_pool, txg); |
| |
| if (zilog_is_dirty(zilog)) |
| zfs_dbgmsg("zil (%px) is dirty, txg %llu", zilog, txg); |
| if (txg < spa_freeze_txg(zilog->zl_spa)) |
| VERIFY(!zilog_is_dirty(zilog)); |
| |
| zilog->zl_get_data = NULL; |
| |
| /* |
| * We should have only one lwb left on the list; remove it now. |
| */ |
| mutex_enter(&zilog->zl_lock); |
| lwb = list_head(&zilog->zl_lwb_list); |
| if (lwb != NULL) { |
| ASSERT3P(lwb, ==, list_tail(&zilog->zl_lwb_list)); |
| ASSERT3S(lwb->lwb_state, !=, LWB_STATE_ISSUED); |
| |
| if (lwb->lwb_fastwrite) |
| metaslab_fastwrite_unmark(zilog->zl_spa, &lwb->lwb_blk); |
| |
| list_remove(&zilog->zl_lwb_list, lwb); |
| zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); |
| zil_free_lwb(zilog, lwb); |
| } |
| mutex_exit(&zilog->zl_lock); |
| } |
| |
| static char *suspend_tag = "zil suspending"; |
| |
| /* |
| * Suspend an intent log. While in suspended mode, we still honor |
| * synchronous semantics, but we rely on txg_wait_synced() to do it. |
| * On old version pools, we suspend the log briefly when taking a |
| * snapshot so that it will have an empty intent log. |
| * |
| * Long holds are not really intended to be used the way we do here -- |
| * held for such a short time. A concurrent caller of dsl_dataset_long_held() |
| * could fail. Therefore we take pains to only put a long hold if it is |
| * actually necessary. Fortunately, it will only be necessary if the |
| * objset is currently mounted (or the ZVOL equivalent). In that case it |
| * will already have a long hold, so we are not really making things any worse. |
| * |
| * Ideally, we would locate the existing long-holder (i.e. the zfsvfs_t or |
| * zvol_state_t), and use their mechanism to prevent their hold from being |
| * dropped (e.g. VFS_HOLD()). However, that would be even more pain for |
| * very little gain. |
| * |
| * if cookiep == NULL, this does both the suspend & resume. |
| * Otherwise, it returns with the dataset "long held", and the cookie |
| * should be passed into zil_resume(). |
| */ |
| int |
| zil_suspend(const char *osname, void **cookiep) |
| { |
| objset_t *os; |
| zilog_t *zilog; |
| const zil_header_t *zh; |
| int error; |
| |
| error = dmu_objset_hold(osname, suspend_tag, &os); |
| if (error != 0) |
| return (error); |
| zilog = dmu_objset_zil(os); |
| |
| mutex_enter(&zilog->zl_lock); |
| zh = zilog->zl_header; |
| |
| if (zh->zh_flags & ZIL_REPLAY_NEEDED) { /* unplayed log */ |
| mutex_exit(&zilog->zl_lock); |
| dmu_objset_rele(os, suspend_tag); |
| return (SET_ERROR(EBUSY)); |
| } |
| |
| /* |
| * Don't put a long hold in the cases where we can avoid it. This |
| * is when there is no cookie so we are doing a suspend & resume |
| * (i.e. called from zil_vdev_offline()), and there's nothing to do |
| * for the suspend because it's already suspended, or there's no ZIL. |
| */ |
| if (cookiep == NULL && !zilog->zl_suspending && |
| (zilog->zl_suspend > 0 || BP_IS_HOLE(&zh->zh_log))) { |
| mutex_exit(&zilog->zl_lock); |
| dmu_objset_rele(os, suspend_tag); |
| return (0); |
| } |
| |
| dsl_dataset_long_hold(dmu_objset_ds(os), suspend_tag); |
| dsl_pool_rele(dmu_objset_pool(os), suspend_tag); |
| |
| zilog->zl_suspend++; |
| |
| if (zilog->zl_suspend > 1) { |
| /* |
| * Someone else is already suspending it. |
| * Just wait for them to finish. |
| */ |
| |
| while (zilog->zl_suspending) |
| cv_wait(&zilog->zl_cv_suspend, &zilog->zl_lock); |
| mutex_exit(&zilog->zl_lock); |
| |
| if (cookiep == NULL) |
| zil_resume(os); |
| else |
| *cookiep = os; |
| return (0); |
| } |
| |
| /* |
| * If there is no pointer to an on-disk block, this ZIL must not |
| * be active (e.g. filesystem not mounted), so there's nothing |
| * to clean up. |
| */ |
| if (BP_IS_HOLE(&zh->zh_log)) { |
| ASSERT(cookiep != NULL); /* fast path already handled */ |
| |
| *cookiep = os; |
| mutex_exit(&zilog->zl_lock); |
| return (0); |
| } |
| |
| /* |
| * The ZIL has work to do. Ensure that the associated encryption |
| * key will remain mapped while we are committing the log by |
| * grabbing a reference to it. If the key isn't loaded we have no |
| * choice but to return an error until the wrapping key is loaded. |
| */ |
| if (os->os_encrypted && |
| dsl_dataset_create_key_mapping(dmu_objset_ds(os)) != 0) { |
| zilog->zl_suspend--; |
| mutex_exit(&zilog->zl_lock); |
| dsl_dataset_long_rele(dmu_objset_ds(os), suspend_tag); |
| dsl_dataset_rele(dmu_objset_ds(os), suspend_tag); |
| return (SET_ERROR(EACCES)); |
| } |
| |
| zilog->zl_suspending = B_TRUE; |
| mutex_exit(&zilog->zl_lock); |
| |
| /* |
| * We need to use zil_commit_impl to ensure we wait for all |
| * LWB_STATE_OPENED and LWB_STATE_ISSUED lwbs to be committed |
| * to disk before proceeding. If we used zil_commit instead, it |
| * would just call txg_wait_synced(), because zl_suspend is set. |
| * txg_wait_synced() doesn't wait for these lwb's to be |
| * LWB_STATE_FLUSH_DONE before returning. |
| */ |
| zil_commit_impl(zilog, 0); |
| |
| /* |
| * Now that we've ensured all lwb's are LWB_STATE_FLUSH_DONE, we |
| * use txg_wait_synced() to ensure the data from the zilog has |
| * migrated to the main pool before calling zil_destroy(). |
| */ |
| txg_wait_synced(zilog->zl_dmu_pool, 0); |
| |
| zil_destroy(zilog, B_FALSE); |
| |
| mutex_enter(&zilog->zl_lock); |
| zilog->zl_suspending = B_FALSE; |
| cv_broadcast(&zilog->zl_cv_suspend); |
| mutex_exit(&zilog->zl_lock); |
| |
| if (os->os_encrypted) |
| dsl_dataset_remove_key_mapping(dmu_objset_ds(os)); |
| |
| if (cookiep == NULL) |
| zil_resume(os); |
| else |
| *cookiep = os; |
| return (0); |
| } |
| |
| void |
| zil_resume(void *cookie) |
| { |
| objset_t *os = cookie; |
| zilog_t *zilog = dmu_objset_zil(os); |
| |
| mutex_enter(&zilog->zl_lock); |
| ASSERT(zilog->zl_suspend != 0); |
| zilog->zl_suspend--; |
| mutex_exit(&zilog->zl_lock); |
| dsl_dataset_long_rele(dmu_objset_ds(os), suspend_tag); |
| dsl_dataset_rele(dmu_objset_ds(os), suspend_tag); |
| } |
| |
| typedef struct zil_replay_arg { |
| zil_replay_func_t **zr_replay; |
| void *zr_arg; |
| boolean_t zr_byteswap; |
| char *zr_lr; |
| } zil_replay_arg_t; |
| |
| static int |
| zil_replay_error(zilog_t *zilog, lr_t *lr, int error) |
| { |
| char name[ZFS_MAX_DATASET_NAME_LEN]; |
| |
| zilog->zl_replaying_seq--; /* didn't actually replay this one */ |
| |
| dmu_objset_name(zilog->zl_os, name); |
| |
| cmn_err(CE_WARN, "ZFS replay transaction error %d, " |
| "dataset %s, seq 0x%llx, txtype %llu %s\n", error, name, |
| (u_longlong_t)lr->lrc_seq, |
| (u_longlong_t)(lr->lrc_txtype & ~TX_CI), |
| (lr->lrc_txtype & TX_CI) ? "CI" : ""); |
| |
| return (error); |
| } |
| |
| static int |
| zil_replay_log_record(zilog_t *zilog, lr_t *lr, void *zra, uint64_t claim_txg) |
| { |
| zil_replay_arg_t *zr = zra; |
| const zil_header_t *zh = zilog->zl_header; |
| uint64_t reclen = lr->lrc_reclen; |
| uint64_t txtype = lr->lrc_txtype; |
| int error = 0; |
| |
| zilog->zl_replaying_seq = lr->lrc_seq; |
| |
| if (lr->lrc_seq <= zh->zh_replay_seq) /* already replayed */ |
| return (0); |
| |
| if (lr->lrc_txg < claim_txg) /* already committed */ |
| return (0); |
| |
| /* Strip case-insensitive bit, still present in log record */ |
| txtype &= ~TX_CI; |
| |
| if (txtype == 0 || txtype >= TX_MAX_TYPE) |
| return (zil_replay_error(zilog, lr, EINVAL)); |
| |
| /* |
| * If this record type can be logged out of order, the object |
| * (lr_foid) may no longer exist. That's legitimate, not an error. |
| */ |
| if (TX_OOO(txtype)) { |
| error = dmu_object_info(zilog->zl_os, |
| LR_FOID_GET_OBJ(((lr_ooo_t *)lr)->lr_foid), NULL); |
| if (error == ENOENT || error == EEXIST) |
| return (0); |
| } |
| |
| /* |
| * Make a copy of the data so we can revise and extend it. |
| */ |
| bcopy(lr, zr->zr_lr, reclen); |
| |
| /* |
| * If this is a TX_WRITE with a blkptr, suck in the data. |
| */ |
| if (txtype == TX_WRITE && reclen == sizeof (lr_write_t)) { |
| error = zil_read_log_data(zilog, (lr_write_t *)lr, |
| zr->zr_lr + reclen); |
| if (error != 0) |
| return (zil_replay_error(zilog, lr, error)); |
| } |
| |
| /* |
| * The log block containing this lr may have been byteswapped |
| * so that we can easily examine common fields like lrc_txtype. |
| * However, the log is a mix of different record types, and only the |
| * replay vectors know how to byteswap their records. Therefore, if |
| * the lr was byteswapped, undo it before invoking the replay vector. |
| */ |
| if (zr->zr_byteswap) |
| byteswap_uint64_array(zr->zr_lr, reclen); |
| |
| /* |
| * We must now do two things atomically: replay this log record, |
| * and update the log header sequence number to reflect the fact that |
| * we did so. At the end of each replay function the sequence number |
| * is updated if we are in replay mode. |
| */ |
| error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, zr->zr_byteswap); |
| if (error != 0) { |
| /* |
| * The DMU's dnode layer doesn't see removes until the txg |
| * commits, so a subsequent claim can spuriously fail with |
| * EEXIST. So if we receive any error we try syncing out |
| * any removes then retry the transaction. Note that we |
| * specify B_FALSE for byteswap now, so we don't do it twice. |
| */ |
| txg_wait_synced(spa_get_dsl(zilog->zl_spa), 0); |
| error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, B_FALSE); |
| if (error != 0) |
| return (zil_replay_error(zilog, lr, error)); |
| } |
| return (0); |
| } |
| |
| /* ARGSUSED */ |
| static int |
| zil_incr_blks(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) |
| { |
| zilog->zl_replay_blks++; |
| |
| return (0); |
| } |
| |
| /* |
| * If this dataset has a non-empty intent log, replay it and destroy it. |
| */ |
| void |
| zil_replay(objset_t *os, void *arg, zil_replay_func_t *replay_func[TX_MAX_TYPE]) |
| { |
| zilog_t *zilog = dmu_objset_zil(os); |
| const zil_header_t *zh = zilog->zl_header; |
| zil_replay_arg_t zr; |
| |
| if ((zh->zh_flags & ZIL_REPLAY_NEEDED) == 0) { |
| zil_destroy(zilog, B_TRUE); |
| return; |
| } |
| |
| zr.zr_replay = replay_func; |
| zr.zr_arg = arg; |
| zr.zr_byteswap = BP_SHOULD_BYTESWAP(&zh->zh_log); |
| zr.zr_lr = vmem_alloc(2 * SPA_MAXBLOCKSIZE, KM_SLEEP); |
| |
| /* |
| * Wait for in-progress removes to sync before starting replay. |
| */ |
| txg_wait_synced(zilog->zl_dmu_pool, 0); |
| |
| zilog->zl_replay = B_TRUE; |
| zilog->zl_replay_time = ddi_get_lbolt(); |
| ASSERT(zilog->zl_replay_blks == 0); |
| (void) zil_parse(zilog, zil_incr_blks, zil_replay_log_record, &zr, |
| zh->zh_claim_txg, B_TRUE); |
| vmem_free(zr.zr_lr, 2 * SPA_MAXBLOCKSIZE); |
| |
| zil_destroy(zilog, B_FALSE); |
| txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg); |
| zilog->zl_replay = B_FALSE; |
| } |
| |
| boolean_t |
| zil_replaying(zilog_t *zilog, dmu_tx_t *tx) |
| { |
| if (zilog->zl_sync == ZFS_SYNC_DISABLED) |
| return (B_TRUE); |
| |
| if (zilog->zl_replay) { |
| dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); |
| zilog->zl_replayed_seq[dmu_tx_get_txg(tx) & TXG_MASK] = |
| zilog->zl_replaying_seq; |
| return (B_TRUE); |
| } |
| |
| return (B_FALSE); |
| } |
| |
| /* ARGSUSED */ |
| int |
| zil_reset(const char *osname, void *arg) |
| { |
| int error; |
| |
| error = zil_suspend(osname, NULL); |
| /* EACCES means crypto key not loaded */ |
| if ((error == EACCES) || (error == EBUSY)) |
| return (SET_ERROR(error)); |
| if (error != 0) |
| return (SET_ERROR(EEXIST)); |
| return (0); |
| } |
| |
| #if defined(_KERNEL) |
| EXPORT_SYMBOL(zil_alloc); |
| EXPORT_SYMBOL(zil_free); |
| EXPORT_SYMBOL(zil_open); |
| EXPORT_SYMBOL(zil_close); |
| EXPORT_SYMBOL(zil_replay); |
| EXPORT_SYMBOL(zil_replaying); |
| EXPORT_SYMBOL(zil_destroy); |
| EXPORT_SYMBOL(zil_destroy_sync); |
| EXPORT_SYMBOL(zil_itx_create); |
| EXPORT_SYMBOL(zil_itx_destroy); |
| EXPORT_SYMBOL(zil_itx_assign); |
| EXPORT_SYMBOL(zil_commit); |
| EXPORT_SYMBOL(zil_claim); |
| EXPORT_SYMBOL(zil_check_log_chain); |
| EXPORT_SYMBOL(zil_sync); |
| EXPORT_SYMBOL(zil_clean); |
| EXPORT_SYMBOL(zil_suspend); |
| EXPORT_SYMBOL(zil_resume); |
| EXPORT_SYMBOL(zil_lwb_add_block); |
| EXPORT_SYMBOL(zil_bp_tree_add); |
| EXPORT_SYMBOL(zil_set_sync); |
| EXPORT_SYMBOL(zil_set_logbias); |
| |
| /* BEGIN CSTYLED */ |
| module_param(zfs_commit_timeout_pct, int, 0644); |
| MODULE_PARM_DESC(zfs_commit_timeout_pct, "ZIL block open timeout percentage"); |
| |
| module_param(zil_replay_disable, int, 0644); |
| MODULE_PARM_DESC(zil_replay_disable, "Disable intent logging replay"); |
| |
| module_param(zil_nocacheflush, int, 0644); |
| MODULE_PARM_DESC(zil_nocacheflush, "Disable ZIL cache flushes"); |
| |
| module_param(zil_slog_bulk, ulong, 0644); |
| MODULE_PARM_DESC(zil_slog_bulk, "Limit in bytes slog sync writes per commit"); |
| |
| module_param(zil_maxblocksize, int, 0644); |
| MODULE_PARM_DESC(zil_maxblocksize, "Limit in bytes of ZIL log block size"); |
| /* END CSTYLED */ |
| #endif |