diff --git a/module/zfs/dmu.c b/module/zfs/dmu.c index e0cdd9e3f33e..6cf7f3c3b12e 100644 --- a/module/zfs/dmu.c +++ b/module/zfs/dmu.c @@ -1,2593 +1,2608 @@ /* * 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 https://opensource.org/licenses/CDDL-1.0. * 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, 2020 by Delphix. All rights reserved. * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. * Copyright (c) 2013, Joyent, Inc. All rights reserved. * Copyright (c) 2016, Nexenta Systems, Inc. All rights reserved. * Copyright (c) 2015 by Chunwei Chen. All rights reserved. * Copyright (c) 2019 Datto Inc. * Copyright (c) 2019, Klara Inc. * Copyright (c) 2019, Allan Jude * Copyright (c) 2022 Hewlett Packard Enterprise Development LP. * Copyright (c) 2021, 2022 by Pawel Jakub Dawidek */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef _KERNEL #include #include #endif /* * Enable/disable nopwrite feature. */ static int zfs_nopwrite_enabled = 1; /* * Tunable to control percentage of dirtied L1 blocks from frees allowed into * one TXG. After this threshold is crossed, additional dirty blocks from frees * will wait until the next TXG. * A value of zero will disable this throttle. */ static uint_t zfs_per_txg_dirty_frees_percent = 30; /* * Enable/disable forcing txg sync when dirty checking for holes with lseek(). * By default this is enabled to ensure accurate hole reporting, it can result * in a significant performance penalty for lseek(SEEK_HOLE) heavy workloads. * Disabling this option will result in holes never being reported in dirty * files which is always safe. */ static int zfs_dmu_offset_next_sync = 1; /* * Limit the amount we can prefetch with one call to this amount. This * helps to limit the amount of memory that can be used by prefetching. * Larger objects should be prefetched a bit at a time. */ #ifdef _ILP32 uint_t dmu_prefetch_max = 8 * 1024 * 1024; #else uint_t dmu_prefetch_max = 8 * SPA_MAXBLOCKSIZE; #endif const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = { {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "unallocated" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "object directory" }, {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "object array" }, {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "packed nvlist" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "packed nvlist size" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj header" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA space map header" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA space map" }, {DMU_BSWAP_UINT64, TRUE, FALSE, TRUE, "ZIL intent log" }, {DMU_BSWAP_DNODE, TRUE, FALSE, TRUE, "DMU dnode" }, {DMU_BSWAP_OBJSET, TRUE, TRUE, FALSE, "DMU objset" }, {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL directory" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL directory child map"}, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dataset snap map" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL props" }, {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL dataset" }, {DMU_BSWAP_ZNODE, TRUE, FALSE, FALSE, "ZFS znode" }, {DMU_BSWAP_OLDACL, TRUE, FALSE, TRUE, "ZFS V0 ACL" }, {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "ZFS plain file" }, {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS directory" }, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "ZFS master node" }, {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS delete queue" }, {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "zvol object" }, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "zvol prop" }, {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "other uint8[]" }, {DMU_BSWAP_UINT64, FALSE, FALSE, TRUE, "other uint64[]" }, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "other ZAP" }, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "persistent error log" }, {DMU_BSWAP_UINT8, TRUE, FALSE, FALSE, "SPA history" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "SPA history offsets" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "Pool properties" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL permissions" }, {DMU_BSWAP_ACL, TRUE, FALSE, TRUE, "ZFS ACL" }, {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "ZFS SYSACL" }, {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "FUID table" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "FUID table size" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dataset next clones"}, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "scan work queue" }, {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS user/group/project used" }, {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "ZFS user/group/project quota"}, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "snapshot refcount tags"}, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "DDT ZAP algorithm" }, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "DDT statistics" }, {DMU_BSWAP_UINT8, TRUE, FALSE, TRUE, "System attributes" }, {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA master node" }, {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA attr registration" }, {DMU_BSWAP_ZAP, TRUE, FALSE, TRUE, "SA attr layouts" }, {DMU_BSWAP_ZAP, TRUE, FALSE, FALSE, "scan translations" }, {DMU_BSWAP_UINT8, FALSE, FALSE, TRUE, "deduplicated block" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL deadlist map" }, {DMU_BSWAP_UINT64, TRUE, TRUE, FALSE, "DSL deadlist map hdr" }, {DMU_BSWAP_ZAP, TRUE, TRUE, FALSE, "DSL dir clones" }, {DMU_BSWAP_UINT64, TRUE, FALSE, FALSE, "bpobj subobj" } }; dmu_object_byteswap_info_t dmu_ot_byteswap[DMU_BSWAP_NUMFUNCS] = { { byteswap_uint8_array, "uint8" }, { byteswap_uint16_array, "uint16" }, { byteswap_uint32_array, "uint32" }, { byteswap_uint64_array, "uint64" }, { zap_byteswap, "zap" }, { dnode_buf_byteswap, "dnode" }, { dmu_objset_byteswap, "objset" }, { zfs_znode_byteswap, "znode" }, { zfs_oldacl_byteswap, "oldacl" }, { zfs_acl_byteswap, "acl" } }; int dmu_buf_hold_noread_by_dnode(dnode_t *dn, uint64_t offset, const void *tag, dmu_buf_t **dbp) { uint64_t blkid; dmu_buf_impl_t *db; rw_enter(&dn->dn_struct_rwlock, RW_READER); blkid = dbuf_whichblock(dn, 0, offset); db = dbuf_hold(dn, blkid, tag); rw_exit(&dn->dn_struct_rwlock); if (db == NULL) { *dbp = NULL; return (SET_ERROR(EIO)); } *dbp = &db->db; return (0); } int dmu_buf_hold_noread(objset_t *os, uint64_t object, uint64_t offset, const void *tag, dmu_buf_t **dbp) { dnode_t *dn; uint64_t blkid; dmu_buf_impl_t *db; int err; err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); rw_enter(&dn->dn_struct_rwlock, RW_READER); blkid = dbuf_whichblock(dn, 0, offset); db = dbuf_hold(dn, blkid, tag); rw_exit(&dn->dn_struct_rwlock); dnode_rele(dn, FTAG); if (db == NULL) { *dbp = NULL; return (SET_ERROR(EIO)); } *dbp = &db->db; return (err); } int dmu_buf_hold_by_dnode(dnode_t *dn, uint64_t offset, const void *tag, dmu_buf_t **dbp, int flags) { int err; int db_flags = DB_RF_CANFAIL; if (flags & DMU_READ_NO_PREFETCH) db_flags |= DB_RF_NOPREFETCH; if (flags & DMU_READ_NO_DECRYPT) db_flags |= DB_RF_NO_DECRYPT; err = dmu_buf_hold_noread_by_dnode(dn, offset, tag, dbp); if (err == 0) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)(*dbp); err = dbuf_read(db, NULL, db_flags); if (err != 0) { dbuf_rele(db, tag); *dbp = NULL; } } return (err); } int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset, const void *tag, dmu_buf_t **dbp, int flags) { int err; int db_flags = DB_RF_CANFAIL; if (flags & DMU_READ_NO_PREFETCH) db_flags |= DB_RF_NOPREFETCH; if (flags & DMU_READ_NO_DECRYPT) db_flags |= DB_RF_NO_DECRYPT; err = dmu_buf_hold_noread(os, object, offset, tag, dbp); if (err == 0) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)(*dbp); err = dbuf_read(db, NULL, db_flags); if (err != 0) { dbuf_rele(db, tag); *dbp = NULL; } } return (err); } int dmu_bonus_max(void) { return (DN_OLD_MAX_BONUSLEN); } int dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; dnode_t *dn; int error; DB_DNODE_ENTER(db); dn = DB_DNODE(db); if (dn->dn_bonus != db) { error = SET_ERROR(EINVAL); } else if (newsize < 0 || newsize > db_fake->db_size) { error = SET_ERROR(EINVAL); } else { dnode_setbonuslen(dn, newsize, tx); error = 0; } DB_DNODE_EXIT(db); return (error); } int dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; dnode_t *dn; int error; DB_DNODE_ENTER(db); dn = DB_DNODE(db); if (!DMU_OT_IS_VALID(type)) { error = SET_ERROR(EINVAL); } else if (dn->dn_bonus != db) { error = SET_ERROR(EINVAL); } else { dnode_setbonus_type(dn, type, tx); error = 0; } DB_DNODE_EXIT(db); return (error); } dmu_object_type_t dmu_get_bonustype(dmu_buf_t *db_fake) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; dnode_t *dn; dmu_object_type_t type; DB_DNODE_ENTER(db); dn = DB_DNODE(db); type = dn->dn_bonustype; DB_DNODE_EXIT(db); return (type); } int dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx) { dnode_t *dn; int error; error = dnode_hold(os, object, FTAG, &dn); dbuf_rm_spill(dn, tx); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); dnode_rm_spill(dn, tx); rw_exit(&dn->dn_struct_rwlock); dnode_rele(dn, FTAG); return (error); } /* * Lookup and hold the bonus buffer for the provided dnode. If the dnode * has not yet been allocated a new bonus dbuf a will be allocated. * Returns ENOENT, EIO, or 0. */ int dmu_bonus_hold_by_dnode(dnode_t *dn, const void *tag, dmu_buf_t **dbp, uint32_t flags) { dmu_buf_impl_t *db; int error; uint32_t db_flags = DB_RF_MUST_SUCCEED; if (flags & DMU_READ_NO_PREFETCH) db_flags |= DB_RF_NOPREFETCH; if (flags & DMU_READ_NO_DECRYPT) db_flags |= DB_RF_NO_DECRYPT; rw_enter(&dn->dn_struct_rwlock, RW_READER); if (dn->dn_bonus == NULL) { if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { rw_exit(&dn->dn_struct_rwlock); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); } if (dn->dn_bonus == NULL) dbuf_create_bonus(dn); } db = dn->dn_bonus; /* as long as the bonus buf is held, the dnode will be held */ if (zfs_refcount_add(&db->db_holds, tag) == 1) { VERIFY(dnode_add_ref(dn, db)); atomic_inc_32(&dn->dn_dbufs_count); } /* * Wait to drop dn_struct_rwlock until after adding the bonus dbuf's * hold and incrementing the dbuf count to ensure that dnode_move() sees * a dnode hold for every dbuf. */ rw_exit(&dn->dn_struct_rwlock); error = dbuf_read(db, NULL, db_flags); if (error) { dnode_evict_bonus(dn); dbuf_rele(db, tag); *dbp = NULL; return (error); } *dbp = &db->db; return (0); } int dmu_bonus_hold(objset_t *os, uint64_t object, const void *tag, dmu_buf_t **dbp) { dnode_t *dn; int error; error = dnode_hold(os, object, FTAG, &dn); if (error) return (error); error = dmu_bonus_hold_by_dnode(dn, tag, dbp, DMU_READ_NO_PREFETCH); dnode_rele(dn, FTAG); return (error); } /* * returns ENOENT, EIO, or 0. * * This interface will allocate a blank spill dbuf when a spill blk * doesn't already exist on the dnode. * * if you only want to find an already existing spill db, then * dmu_spill_hold_existing() should be used. */ int dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, const void *tag, dmu_buf_t **dbp) { dmu_buf_impl_t *db = NULL; int err; if ((flags & DB_RF_HAVESTRUCT) == 0) rw_enter(&dn->dn_struct_rwlock, RW_READER); db = dbuf_hold(dn, DMU_SPILL_BLKID, tag); if ((flags & DB_RF_HAVESTRUCT) == 0) rw_exit(&dn->dn_struct_rwlock); if (db == NULL) { *dbp = NULL; return (SET_ERROR(EIO)); } err = dbuf_read(db, NULL, flags); if (err == 0) *dbp = &db->db; else { dbuf_rele(db, tag); *dbp = NULL; } return (err); } int dmu_spill_hold_existing(dmu_buf_t *bonus, const void *tag, dmu_buf_t **dbp) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; dnode_t *dn; int err; DB_DNODE_ENTER(db); dn = DB_DNODE(db); if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) { err = SET_ERROR(EINVAL); } else { rw_enter(&dn->dn_struct_rwlock, RW_READER); if (!dn->dn_have_spill) { err = SET_ERROR(ENOENT); } else { err = dmu_spill_hold_by_dnode(dn, DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp); } rw_exit(&dn->dn_struct_rwlock); } DB_DNODE_EXIT(db); return (err); } int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, uint32_t flags, const void *tag, dmu_buf_t **dbp) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus; dnode_t *dn; int err; uint32_t db_flags = DB_RF_CANFAIL; if (flags & DMU_READ_NO_DECRYPT) db_flags |= DB_RF_NO_DECRYPT; DB_DNODE_ENTER(db); dn = DB_DNODE(db); err = dmu_spill_hold_by_dnode(dn, db_flags, tag, dbp); DB_DNODE_EXIT(db); return (err); } /* * Note: longer-term, we should modify all of the dmu_buf_*() interfaces * to take a held dnode rather than -- the lookup is wasteful, * and can induce severe lock contention when writing to several files * whose dnodes are in the same block. */ int dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length, boolean_t read, const void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags) { dmu_buf_t **dbp; zstream_t *zs = NULL; uint64_t blkid, nblks, i; uint32_t dbuf_flags; int err; zio_t *zio = NULL; boolean_t missed = B_FALSE; ASSERT(!read || length <= DMU_MAX_ACCESS); /* * Note: We directly notify the prefetch code of this read, so that * we can tell it about the multi-block read. dbuf_read() only knows * about the one block it is accessing. */ dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT | DB_RF_NOPREFETCH; if ((flags & DMU_READ_NO_DECRYPT) != 0) dbuf_flags |= DB_RF_NO_DECRYPT; rw_enter(&dn->dn_struct_rwlock, RW_READER); if (dn->dn_datablkshift) { int blkshift = dn->dn_datablkshift; nblks = (P2ROUNDUP(offset + length, 1ULL << blkshift) - P2ALIGN(offset, 1ULL << blkshift)) >> blkshift; } else { if (offset + length > dn->dn_datablksz) { zfs_panic_recover("zfs: accessing past end of object " "%llx/%llx (size=%u access=%llu+%llu)", (longlong_t)dn->dn_objset-> os_dsl_dataset->ds_object, (longlong_t)dn->dn_object, dn->dn_datablksz, (longlong_t)offset, (longlong_t)length); rw_exit(&dn->dn_struct_rwlock); return (SET_ERROR(EIO)); } nblks = 1; } dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP); if (read) zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL); blkid = dbuf_whichblock(dn, 0, offset); if ((flags & DMU_READ_NO_PREFETCH) == 0) { /* * Prepare the zfetch before initiating the demand reads, so * that if multiple threads block on same indirect block, we * base predictions on the original less racy request order. */ zs = dmu_zfetch_prepare(&dn->dn_zfetch, blkid, nblks, read, B_TRUE); } for (i = 0; i < nblks; i++) { dmu_buf_impl_t *db = dbuf_hold(dn, blkid + i, tag); if (db == NULL) { if (zs) dmu_zfetch_run(zs, missed, B_TRUE); rw_exit(&dn->dn_struct_rwlock); dmu_buf_rele_array(dbp, nblks, tag); if (read) zio_nowait(zio); return (SET_ERROR(EIO)); } /* * Initiate async demand data read. * We check the db_state after calling dbuf_read() because * (1) dbuf_read() may change the state to CACHED due to a * hit in the ARC, and (2) on a cache miss, a child will * have been added to "zio" but not yet completed, so the * state will not yet be CACHED. */ if (read) { if (i == nblks - 1 && blkid + i < dn->dn_maxblkid && offset + length < db->db.db_offset + db->db.db_size) { if (offset <= db->db.db_offset) dbuf_flags |= DB_RF_PARTIAL_FIRST; else dbuf_flags |= DB_RF_PARTIAL_MORE; } (void) dbuf_read(db, zio, dbuf_flags); if (db->db_state != DB_CACHED) missed = B_TRUE; } dbp[i] = &db->db; } if (!read) zfs_racct_write(length, nblks); if (zs) dmu_zfetch_run(zs, missed, B_TRUE); rw_exit(&dn->dn_struct_rwlock); if (read) { /* wait for async read i/o */ err = zio_wait(zio); if (err) { dmu_buf_rele_array(dbp, nblks, tag); return (err); } /* wait for other io to complete */ for (i = 0; i < nblks; i++) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i]; mutex_enter(&db->db_mtx); while (db->db_state == DB_READ || db->db_state == DB_FILL) cv_wait(&db->db_changed, &db->db_mtx); if (db->db_state == DB_UNCACHED) err = SET_ERROR(EIO); mutex_exit(&db->db_mtx); if (err) { dmu_buf_rele_array(dbp, nblks, tag); return (err); } } } *numbufsp = nblks; *dbpp = dbp; return (0); } int dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset, uint64_t length, int read, const void *tag, int *numbufsp, dmu_buf_t ***dbpp) { dnode_t *dn; int err; err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, numbufsp, dbpp, DMU_READ_PREFETCH); dnode_rele(dn, FTAG); return (err); } int dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset, uint64_t length, boolean_t read, const void *tag, int *numbufsp, dmu_buf_t ***dbpp) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; dnode_t *dn; int err; DB_DNODE_ENTER(db); dn = DB_DNODE(db); err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag, numbufsp, dbpp, DMU_READ_PREFETCH); DB_DNODE_EXIT(db); return (err); } void dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, const void *tag) { int i; dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake; if (numbufs == 0) return; for (i = 0; i < numbufs; i++) { if (dbp[i]) dbuf_rele(dbp[i], tag); } kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs); } /* * Issue prefetch I/Os for the given blocks. If level is greater than 0, the * indirect blocks prefetched will be those that point to the blocks containing * the data starting at offset, and continuing to offset + len. If the range * it too long, prefetch the first dmu_prefetch_max bytes as requested, while * for the rest only a higher level, also fitting within dmu_prefetch_max. It * should primarily help random reads, since for long sequential reads there is * a speculative prefetcher. * * Note that if the indirect blocks above the blocks being prefetched are not * in cache, they will be asynchronously read in. Dnode read by dnode_hold() * is currently synchronous. */ void dmu_prefetch(objset_t *os, uint64_t object, int64_t level, uint64_t offset, uint64_t len, zio_priority_t pri) { dnode_t *dn; int64_t level2 = level; uint64_t start, end, start2, end2; if (dmu_prefetch_max == 0 || len == 0) { dmu_prefetch_dnode(os, object, pri); return; } if (dnode_hold(os, object, FTAG, &dn) != 0) return; /* * Depending on len we may do two prefetches: blocks [start, end) at * level, and following blocks [start2, end2) at higher level2. */ rw_enter(&dn->dn_struct_rwlock, RW_READER); if (dn->dn_datablkshift != 0) { /* * The object has multiple blocks. Calculate the full range * of blocks [start, end2) and then split it into two parts, * so that the first [start, end) fits into dmu_prefetch_max. */ start = dbuf_whichblock(dn, level, offset); end2 = dbuf_whichblock(dn, level, offset + len - 1) + 1; uint8_t ibs = dn->dn_indblkshift; uint8_t bs = (level == 0) ? dn->dn_datablkshift : ibs; uint_t limit = P2ROUNDUP(dmu_prefetch_max, 1 << bs) >> bs; start2 = end = MIN(end2, start + limit); /* * Find level2 where [start2, end2) fits into dmu_prefetch_max. */ uint8_t ibps = ibs - SPA_BLKPTRSHIFT; limit = P2ROUNDUP(dmu_prefetch_max, 1 << ibs) >> ibs; do { level2++; start2 = P2ROUNDUP(start2, 1 << ibps) >> ibps; end2 = P2ROUNDUP(end2, 1 << ibps) >> ibps; } while (end2 - start2 > limit); } else { /* There is only one block. Prefetch it or nothing. */ start = start2 = end2 = 0; end = start + (level == 0 && offset < dn->dn_datablksz); } for (uint64_t i = start; i < end; i++) dbuf_prefetch(dn, level, i, pri, 0); for (uint64_t i = start2; i < end2; i++) dbuf_prefetch(dn, level2, i, pri, 0); rw_exit(&dn->dn_struct_rwlock); dnode_rele(dn, FTAG); } /* * Issue prefetch I/Os for the given object's dnode. */ void dmu_prefetch_dnode(objset_t *os, uint64_t object, zio_priority_t pri) { if (object == 0 || object >= DN_MAX_OBJECT) return; dnode_t *dn = DMU_META_DNODE(os); rw_enter(&dn->dn_struct_rwlock, RW_READER); uint64_t blkid = dbuf_whichblock(dn, 0, object * sizeof (dnode_phys_t)); dbuf_prefetch(dn, 0, blkid, pri, 0); rw_exit(&dn->dn_struct_rwlock); } /* * Get the next "chunk" of file data to free. We traverse the file from * the end so that the file gets shorter over time (if we crashes in the * middle, this will leave us in a better state). We find allocated file * data by simply searching the allocated level 1 indirects. * * On input, *start should be the first offset that does not need to be * freed (e.g. "offset + length"). On return, *start will be the first * offset that should be freed and l1blks is set to the number of level 1 * indirect blocks found within the chunk. */ static int get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t minimum, uint64_t *l1blks) { uint64_t blks; uint64_t maxblks = DMU_MAX_ACCESS >> (dn->dn_indblkshift + 1); /* bytes of data covered by a level-1 indirect block */ uint64_t iblkrange = (uint64_t)dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT); ASSERT3U(minimum, <=, *start); /* * Check if we can free the entire range assuming that all of the * L1 blocks in this range have data. If we can, we use this * worst case value as an estimate so we can avoid having to look * at the object's actual data. */ uint64_t total_l1blks = (roundup(*start, iblkrange) - (minimum / iblkrange * iblkrange)) / iblkrange; if (total_l1blks <= maxblks) { *l1blks = total_l1blks; *start = minimum; return (0); } ASSERT(ISP2(iblkrange)); for (blks = 0; *start > minimum && blks < maxblks; blks++) { int err; /* * dnode_next_offset(BACKWARDS) will find an allocated L1 * indirect block at or before the input offset. We must * decrement *start so that it is at the end of the region * to search. */ (*start)--; err = dnode_next_offset(dn, DNODE_FIND_BACKWARDS, start, 2, 1, 0); /* if there are no indirect blocks before start, we are done */ if (err == ESRCH) { *start = minimum; break; } else if (err != 0) { *l1blks = blks; return (err); } /* set start to the beginning of this L1 indirect */ *start = P2ALIGN(*start, iblkrange); } if (*start < minimum) *start = minimum; *l1blks = blks; return (0); } /* * If this objset is of type OST_ZFS return true if vfs's unmounted flag is set, * otherwise return false. * Used below in dmu_free_long_range_impl() to enable abort when unmounting */ static boolean_t dmu_objset_zfs_unmounting(objset_t *os) { #ifdef _KERNEL if (dmu_objset_type(os) == DMU_OST_ZFS) return (zfs_get_vfs_flag_unmounted(os)); #else (void) os; #endif return (B_FALSE); } static int dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset, uint64_t length) { uint64_t object_size; int err; uint64_t dirty_frees_threshold; dsl_pool_t *dp = dmu_objset_pool(os); if (dn == NULL) return (SET_ERROR(EINVAL)); object_size = (dn->dn_maxblkid + 1) * dn->dn_datablksz; if (offset >= object_size) return (0); if (zfs_per_txg_dirty_frees_percent <= 100) dirty_frees_threshold = zfs_per_txg_dirty_frees_percent * zfs_dirty_data_max / 100; else dirty_frees_threshold = zfs_dirty_data_max / 20; if (length == DMU_OBJECT_END || offset + length > object_size) length = object_size - offset; while (length != 0) { uint64_t chunk_end, chunk_begin, chunk_len; uint64_t l1blks; dmu_tx_t *tx; if (dmu_objset_zfs_unmounting(dn->dn_objset)) return (SET_ERROR(EINTR)); chunk_end = chunk_begin = offset + length; /* move chunk_begin backwards to the beginning of this chunk */ err = get_next_chunk(dn, &chunk_begin, offset, &l1blks); if (err) return (err); ASSERT3U(chunk_begin, >=, offset); ASSERT3U(chunk_begin, <=, chunk_end); chunk_len = chunk_end - chunk_begin; tx = dmu_tx_create(os); dmu_tx_hold_free(tx, dn->dn_object, chunk_begin, chunk_len); /* * Mark this transaction as typically resulting in a net * reduction in space used. */ dmu_tx_mark_netfree(tx); err = dmu_tx_assign(tx, TXG_WAIT); if (err) { dmu_tx_abort(tx); return (err); } uint64_t txg = dmu_tx_get_txg(tx); mutex_enter(&dp->dp_lock); uint64_t long_free_dirty = dp->dp_long_free_dirty_pertxg[txg & TXG_MASK]; mutex_exit(&dp->dp_lock); /* * To avoid filling up a TXG with just frees, wait for * the next TXG to open before freeing more chunks if * we have reached the threshold of frees. */ if (dirty_frees_threshold != 0 && long_free_dirty >= dirty_frees_threshold) { DMU_TX_STAT_BUMP(dmu_tx_dirty_frees_delay); dmu_tx_commit(tx); txg_wait_open(dp, 0, B_TRUE); continue; } /* * In order to prevent unnecessary write throttling, for each * TXG, we track the cumulative size of L1 blocks being dirtied * in dnode_free_range() below. We compare this number to a * tunable threshold, past which we prevent new L1 dirty freeing * blocks from being added into the open TXG. See * dmu_free_long_range_impl() for details. The threshold * prevents write throttle activation due to dirty freeing L1 * blocks taking up a large percentage of zfs_dirty_data_max. */ mutex_enter(&dp->dp_lock); dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] += l1blks << dn->dn_indblkshift; mutex_exit(&dp->dp_lock); DTRACE_PROBE3(free__long__range, uint64_t, long_free_dirty, uint64_t, chunk_len, uint64_t, txg); dnode_free_range(dn, chunk_begin, chunk_len, tx); dmu_tx_commit(tx); length -= chunk_len; } return (0); } int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset, uint64_t length) { dnode_t *dn; int err; err = dnode_hold(os, object, FTAG, &dn); if (err != 0) return (err); err = dmu_free_long_range_impl(os, dn, offset, length); /* * It is important to zero out the maxblkid when freeing the entire * file, so that (a) subsequent calls to dmu_free_long_range_impl() * will take the fast path, and (b) dnode_reallocate() can verify * that the entire file has been freed. */ if (err == 0 && offset == 0 && length == DMU_OBJECT_END) dn->dn_maxblkid = 0; dnode_rele(dn, FTAG); return (err); } int dmu_free_long_object(objset_t *os, uint64_t object) { dmu_tx_t *tx; int err; err = dmu_free_long_range(os, object, 0, DMU_OBJECT_END); if (err != 0) return (err); tx = dmu_tx_create(os); dmu_tx_hold_bonus(tx, object); dmu_tx_hold_free(tx, object, 0, DMU_OBJECT_END); dmu_tx_mark_netfree(tx); err = dmu_tx_assign(tx, TXG_WAIT); if (err == 0) { err = dmu_object_free(os, object, tx); dmu_tx_commit(tx); } else { dmu_tx_abort(tx); } return (err); } int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, dmu_tx_t *tx) { dnode_t *dn; int err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); ASSERT(offset < UINT64_MAX); ASSERT(size == DMU_OBJECT_END || size <= UINT64_MAX - offset); dnode_free_range(dn, offset, size, tx); dnode_rele(dn, FTAG); return (0); } static int dmu_read_impl(dnode_t *dn, uint64_t offset, uint64_t size, void *buf, uint32_t flags) { dmu_buf_t **dbp; int numbufs, err = 0; /* * Deal with odd block sizes, where there can't be data past the first * block. If we ever do the tail block optimization, we will need to * handle that here as well. */ if (dn->dn_maxblkid == 0) { uint64_t newsz = offset > dn->dn_datablksz ? 0 : MIN(size, dn->dn_datablksz - offset); memset((char *)buf + newsz, 0, size - newsz); size = newsz; } while (size > 0) { uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2); int i; /* * NB: we could do this block-at-a-time, but it's nice * to be reading in parallel. */ err = dmu_buf_hold_array_by_dnode(dn, offset, mylen, TRUE, FTAG, &numbufs, &dbp, flags); if (err) break; for (i = 0; i < numbufs; i++) { uint64_t tocpy; int64_t bufoff; dmu_buf_t *db = dbp[i]; ASSERT(size > 0); bufoff = offset - db->db_offset; tocpy = MIN(db->db_size - bufoff, size); (void) memcpy(buf, (char *)db->db_data + bufoff, tocpy); offset += tocpy; size -= tocpy; buf = (char *)buf + tocpy; } dmu_buf_rele_array(dbp, numbufs, FTAG); } return (err); } int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, void *buf, uint32_t flags) { dnode_t *dn; int err; err = dnode_hold(os, object, FTAG, &dn); if (err != 0) return (err); err = dmu_read_impl(dn, offset, size, buf, flags); dnode_rele(dn, FTAG); return (err); } int dmu_read_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, void *buf, uint32_t flags) { return (dmu_read_impl(dn, offset, size, buf, flags)); } static void dmu_write_impl(dmu_buf_t **dbp, int numbufs, uint64_t offset, uint64_t size, const void *buf, dmu_tx_t *tx) { int i; for (i = 0; i < numbufs; i++) { uint64_t tocpy; int64_t bufoff; dmu_buf_t *db = dbp[i]; ASSERT(size > 0); bufoff = offset - db->db_offset; tocpy = MIN(db->db_size - bufoff, size); ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); if (tocpy == db->db_size) dmu_buf_will_fill(db, tx); else dmu_buf_will_dirty(db, tx); (void) memcpy((char *)db->db_data + bufoff, buf, tocpy); if (tocpy == db->db_size) dmu_buf_fill_done(db, tx); offset += tocpy; size -= tocpy; buf = (char *)buf + tocpy; } } void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, const void *buf, dmu_tx_t *tx) { dmu_buf_t **dbp; int numbufs; if (size == 0) return; VERIFY0(dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG, &numbufs, &dbp)); dmu_write_impl(dbp, numbufs, offset, size, buf, tx); dmu_buf_rele_array(dbp, numbufs, FTAG); } /* * Note: Lustre is an external consumer of this interface. */ void dmu_write_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size, const void *buf, dmu_tx_t *tx) { dmu_buf_t **dbp; int numbufs; if (size == 0) return; VERIFY0(dmu_buf_hold_array_by_dnode(dn, offset, size, FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH)); dmu_write_impl(dbp, numbufs, offset, size, buf, tx); dmu_buf_rele_array(dbp, numbufs, FTAG); } void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, dmu_tx_t *tx) { dmu_buf_t **dbp; int numbufs, i; if (size == 0) return; VERIFY(0 == dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG, &numbufs, &dbp)); for (i = 0; i < numbufs; i++) { dmu_buf_t *db = dbp[i]; dmu_buf_will_not_fill(db, tx); } dmu_buf_rele_array(dbp, numbufs, FTAG); } void dmu_write_embedded(objset_t *os, uint64_t object, uint64_t offset, void *data, uint8_t etype, uint8_t comp, int uncompressed_size, int compressed_size, int byteorder, dmu_tx_t *tx) { dmu_buf_t *db; ASSERT3U(etype, <, NUM_BP_EMBEDDED_TYPES); ASSERT3U(comp, <, ZIO_COMPRESS_FUNCTIONS); VERIFY0(dmu_buf_hold_noread(os, object, offset, FTAG, &db)); dmu_buf_write_embedded(db, data, (bp_embedded_type_t)etype, (enum zio_compress)comp, uncompressed_size, compressed_size, byteorder, tx); dmu_buf_rele(db, FTAG); } void dmu_redact(objset_t *os, uint64_t object, uint64_t offset, uint64_t size, dmu_tx_t *tx) { int numbufs, i; dmu_buf_t **dbp; VERIFY0(dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG, &numbufs, &dbp)); for (i = 0; i < numbufs; i++) dmu_buf_redact(dbp[i], tx); dmu_buf_rele_array(dbp, numbufs, FTAG); } #ifdef _KERNEL int dmu_read_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size) { dmu_buf_t **dbp; int numbufs, i, err; /* * NB: we could do this block-at-a-time, but it's nice * to be reading in parallel. */ err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), size, TRUE, FTAG, &numbufs, &dbp, 0); if (err) return (err); for (i = 0; i < numbufs; i++) { uint64_t tocpy; int64_t bufoff; dmu_buf_t *db = dbp[i]; ASSERT(size > 0); bufoff = zfs_uio_offset(uio) - db->db_offset; tocpy = MIN(db->db_size - bufoff, size); err = zfs_uio_fault_move((char *)db->db_data + bufoff, tocpy, UIO_READ, uio); if (err) break; size -= tocpy; } dmu_buf_rele_array(dbp, numbufs, FTAG); return (err); } /* * Read 'size' bytes into the uio buffer. * From object zdb->db_object. * Starting at zfs_uio_offset(uio). * * If the caller already has a dbuf in the target object * (e.g. its bonus buffer), this routine is faster than dmu_read_uio(), * because we don't have to find the dnode_t for the object. */ int dmu_read_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; dnode_t *dn; int err; if (size == 0) return (0); DB_DNODE_ENTER(db); dn = DB_DNODE(db); err = dmu_read_uio_dnode(dn, uio, size); DB_DNODE_EXIT(db); return (err); } /* * Read 'size' bytes into the uio buffer. * From the specified object * Starting at offset zfs_uio_offset(uio). */ int dmu_read_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size) { dnode_t *dn; int err; if (size == 0) return (0); err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); err = dmu_read_uio_dnode(dn, uio, size); dnode_rele(dn, FTAG); return (err); } int dmu_write_uio_dnode(dnode_t *dn, zfs_uio_t *uio, uint64_t size, dmu_tx_t *tx) { dmu_buf_t **dbp; int numbufs; int err = 0; int i; err = dmu_buf_hold_array_by_dnode(dn, zfs_uio_offset(uio), size, FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH); if (err) return (err); for (i = 0; i < numbufs; i++) { uint64_t tocpy; int64_t bufoff; dmu_buf_t *db = dbp[i]; ASSERT(size > 0); bufoff = zfs_uio_offset(uio) - db->db_offset; tocpy = MIN(db->db_size - bufoff, size); ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size); if (tocpy == db->db_size) dmu_buf_will_fill(db, tx); else dmu_buf_will_dirty(db, tx); /* * XXX zfs_uiomove could block forever (eg.nfs-backed * pages). There needs to be a uiolockdown() function * to lock the pages in memory, so that zfs_uiomove won't * block. */ err = zfs_uio_fault_move((char *)db->db_data + bufoff, tocpy, UIO_WRITE, uio); if (tocpy == db->db_size) dmu_buf_fill_done(db, tx); if (err) break; size -= tocpy; } dmu_buf_rele_array(dbp, numbufs, FTAG); return (err); } /* * Write 'size' bytes from the uio buffer. * To object zdb->db_object. * Starting at offset zfs_uio_offset(uio). * * If the caller already has a dbuf in the target object * (e.g. its bonus buffer), this routine is faster than dmu_write_uio(), * because we don't have to find the dnode_t for the object. */ int dmu_write_uio_dbuf(dmu_buf_t *zdb, zfs_uio_t *uio, uint64_t size, dmu_tx_t *tx) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb; dnode_t *dn; int err; if (size == 0) return (0); DB_DNODE_ENTER(db); dn = DB_DNODE(db); err = dmu_write_uio_dnode(dn, uio, size, tx); DB_DNODE_EXIT(db); return (err); } /* * Write 'size' bytes from the uio buffer. * To the specified object. * Starting at offset zfs_uio_offset(uio). */ int dmu_write_uio(objset_t *os, uint64_t object, zfs_uio_t *uio, uint64_t size, dmu_tx_t *tx) { dnode_t *dn; int err; if (size == 0) return (0); err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); err = dmu_write_uio_dnode(dn, uio, size, tx); dnode_rele(dn, FTAG); return (err); } #endif /* _KERNEL */ /* * Allocate a loaned anonymous arc buffer. */ arc_buf_t * dmu_request_arcbuf(dmu_buf_t *handle, int size) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle; return (arc_loan_buf(db->db_objset->os_spa, B_FALSE, size)); } /* * Free a loaned arc buffer. */ void dmu_return_arcbuf(arc_buf_t *buf) { arc_return_buf(buf, FTAG); arc_buf_destroy(buf, FTAG); } /* * A "lightweight" write is faster than a regular write (e.g. * dmu_write_by_dnode() or dmu_assign_arcbuf_by_dnode()), because it avoids the * CPU cost of creating a dmu_buf_impl_t and arc_buf_[hdr_]_t. However, the * data can not be read or overwritten until the transaction's txg has been * synced. This makes it appropriate for workloads that are known to be * (temporarily) write-only, like "zfs receive". * * A single block is written, starting at the specified offset in bytes. If * the call is successful, it returns 0 and the provided abd has been * consumed (the caller should not free it). */ int dmu_lightweight_write_by_dnode(dnode_t *dn, uint64_t offset, abd_t *abd, const zio_prop_t *zp, zio_flag_t flags, dmu_tx_t *tx) { dbuf_dirty_record_t *dr = dbuf_dirty_lightweight(dn, dbuf_whichblock(dn, 0, offset), tx); if (dr == NULL) return (SET_ERROR(EIO)); dr->dt.dll.dr_abd = abd; dr->dt.dll.dr_props = *zp; dr->dt.dll.dr_flags = flags; return (0); } /* * When possible directly assign passed loaned arc buffer to a dbuf. * If this is not possible copy the contents of passed arc buf via * dmu_write(). */ int dmu_assign_arcbuf_by_dnode(dnode_t *dn, uint64_t offset, arc_buf_t *buf, dmu_tx_t *tx) { dmu_buf_impl_t *db; objset_t *os = dn->dn_objset; uint64_t object = dn->dn_object; uint32_t blksz = (uint32_t)arc_buf_lsize(buf); uint64_t blkid; rw_enter(&dn->dn_struct_rwlock, RW_READER); blkid = dbuf_whichblock(dn, 0, offset); db = dbuf_hold(dn, blkid, FTAG); if (db == NULL) return (SET_ERROR(EIO)); rw_exit(&dn->dn_struct_rwlock); /* * We can only assign if the offset is aligned and the arc buf is the * same size as the dbuf. */ if (offset == db->db.db_offset && blksz == db->db.db_size) { zfs_racct_write(blksz, 1); dbuf_assign_arcbuf(db, buf, tx); dbuf_rele(db, FTAG); } else { /* compressed bufs must always be assignable to their dbuf */ ASSERT3U(arc_get_compression(buf), ==, ZIO_COMPRESS_OFF); ASSERT(!(buf->b_flags & ARC_BUF_FLAG_COMPRESSED)); dbuf_rele(db, FTAG); dmu_write(os, object, offset, blksz, buf->b_data, tx); dmu_return_arcbuf(buf); } return (0); } int dmu_assign_arcbuf_by_dbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf, dmu_tx_t *tx) { int err; dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle; DB_DNODE_ENTER(dbuf); err = dmu_assign_arcbuf_by_dnode(DB_DNODE(dbuf), offset, buf, tx); DB_DNODE_EXIT(dbuf); return (err); } typedef struct { dbuf_dirty_record_t *dsa_dr; dmu_sync_cb_t *dsa_done; zgd_t *dsa_zgd; dmu_tx_t *dsa_tx; } dmu_sync_arg_t; static void dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg) { (void) buf; dmu_sync_arg_t *dsa = varg; dmu_buf_t *db = dsa->dsa_zgd->zgd_db; blkptr_t *bp = zio->io_bp; if (zio->io_error == 0) { if (BP_IS_HOLE(bp)) { /* * A block of zeros may compress to a hole, but the * block size still needs to be known for replay. */ BP_SET_LSIZE(bp, db->db_size); } else if (!BP_IS_EMBEDDED(bp)) { ASSERT(BP_GET_LEVEL(bp) == 0); BP_SET_FILL(bp, 1); } } } static void dmu_sync_late_arrival_ready(zio_t *zio) { dmu_sync_ready(zio, NULL, zio->io_private); } static void dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg) { (void) buf; dmu_sync_arg_t *dsa = varg; dbuf_dirty_record_t *dr = dsa->dsa_dr; dmu_buf_impl_t *db = dr->dr_dbuf; zgd_t *zgd = dsa->dsa_zgd; /* * Record the vdev(s) backing this blkptr so they can be flushed after * the writes for the lwb have completed. */ if (zio->io_error == 0) { zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp); } mutex_enter(&db->db_mtx); ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC); if (zio->io_error == 0) { dr->dt.dl.dr_nopwrite = !!(zio->io_flags & ZIO_FLAG_NOPWRITE); if (dr->dt.dl.dr_nopwrite) { blkptr_t *bp = zio->io_bp; blkptr_t *bp_orig = &zio->io_bp_orig; uint8_t chksum = BP_GET_CHECKSUM(bp_orig); ASSERT(BP_EQUAL(bp, bp_orig)); VERIFY(BP_EQUAL(bp, db->db_blkptr)); ASSERT(zio->io_prop.zp_compress != ZIO_COMPRESS_OFF); VERIFY(zio_checksum_table[chksum].ci_flags & ZCHECKSUM_FLAG_NOPWRITE); } dr->dt.dl.dr_overridden_by = *zio->io_bp; dr->dt.dl.dr_override_state = DR_OVERRIDDEN; dr->dt.dl.dr_copies = zio->io_prop.zp_copies; /* * Old style holes are filled with all zeros, whereas * new-style holes maintain their lsize, type, level, * and birth time (see zio_write_compress). While we * need to reset the BP_SET_LSIZE() call that happened * in dmu_sync_ready for old style holes, we do *not* * want to wipe out the information contained in new * style holes. Thus, only zero out the block pointer if * it's an old style hole. */ if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by) && dr->dt.dl.dr_overridden_by.blk_birth == 0) BP_ZERO(&dr->dt.dl.dr_overridden_by); } else { dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN; } cv_broadcast(&db->db_changed); mutex_exit(&db->db_mtx); dsa->dsa_done(dsa->dsa_zgd, zio->io_error); kmem_free(dsa, sizeof (*dsa)); } static void dmu_sync_late_arrival_done(zio_t *zio) { blkptr_t *bp = zio->io_bp; dmu_sync_arg_t *dsa = zio->io_private; zgd_t *zgd = dsa->dsa_zgd; if (zio->io_error == 0) { /* * Record the vdev(s) backing this blkptr so they can be * flushed after the writes for the lwb have completed. */ zil_lwb_add_block(zgd->zgd_lwb, zgd->zgd_bp); if (!BP_IS_HOLE(bp)) { blkptr_t *bp_orig __maybe_unused = &zio->io_bp_orig; ASSERT(!(zio->io_flags & ZIO_FLAG_NOPWRITE)); ASSERT(BP_IS_HOLE(bp_orig) || !BP_EQUAL(bp, bp_orig)); ASSERT(zio->io_bp->blk_birth == zio->io_txg); ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa)); zio_free(zio->io_spa, zio->io_txg, zio->io_bp); } } dmu_tx_commit(dsa->dsa_tx); dsa->dsa_done(dsa->dsa_zgd, zio->io_error); abd_free(zio->io_abd); kmem_free(dsa, sizeof (*dsa)); } static int dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd, zio_prop_t *zp, zbookmark_phys_t *zb) { dmu_sync_arg_t *dsa; dmu_tx_t *tx; int error; error = dbuf_read((dmu_buf_impl_t *)zgd->zgd_db, NULL, DB_RF_CANFAIL | DB_RF_NOPREFETCH); if (error != 0) return (error); tx = dmu_tx_create(os); dmu_tx_hold_space(tx, zgd->zgd_db->db_size); /* * This transaction does not produce any dirty data or log blocks, so * it should not be throttled. All other cases wait for TXG sync, by * which time the log block we are writing will be obsolete, so we can * skip waiting and just return error here instead. */ if (dmu_tx_assign(tx, TXG_NOWAIT | TXG_NOTHROTTLE) != 0) { dmu_tx_abort(tx); /* Make zl_get_data do txg_waited_synced() */ return (SET_ERROR(EIO)); } /* * In order to prevent the zgd's lwb from being free'd prior to * dmu_sync_late_arrival_done() being called, we have to ensure * the lwb's "max txg" takes this tx's txg into account. */ zil_lwb_add_txg(zgd->zgd_lwb, dmu_tx_get_txg(tx)); dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); dsa->dsa_dr = NULL; dsa->dsa_done = done; dsa->dsa_zgd = zgd; dsa->dsa_tx = tx; /* * Since we are currently syncing this txg, it's nontrivial to * determine what BP to nopwrite against, so we disable nopwrite. * * When syncing, the db_blkptr is initially the BP of the previous * txg. We can not nopwrite against it because it will be changed * (this is similar to the non-late-arrival case where the dbuf is * dirty in a future txg). * * Then dbuf_write_ready() sets bp_blkptr to the location we will write. * We can not nopwrite against it because although the BP will not * (typically) be changed, the data has not yet been persisted to this * location. * * Finally, when dbuf_write_done() is called, it is theoretically * possible to always nopwrite, because the data that was written in * this txg is the same data that we are trying to write. However we * would need to check that this dbuf is not dirty in any future * txg's (as we do in the normal dmu_sync() path). For simplicity, we * don't nopwrite in this case. */ zp->zp_nopwrite = B_FALSE; zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp, abd_get_from_buf(zgd->zgd_db->db_data, zgd->zgd_db->db_size), zgd->zgd_db->db_size, zgd->zgd_db->db_size, zp, dmu_sync_late_arrival_ready, NULL, dmu_sync_late_arrival_done, dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb)); return (0); } /* * Intent log support: sync the block associated with db to disk. * N.B. and XXX: the caller is responsible for making sure that the * data isn't changing while dmu_sync() is writing it. * * Return values: * * EEXIST: this txg has already been synced, so there's nothing to do. * The caller should not log the write. * * ENOENT: the block was dbuf_free_range()'d, so there's nothing to do. * The caller should not log the write. * * EALREADY: this block is already in the process of being synced. * The caller should track its progress (somehow). * * EIO: could not do the I/O. * The caller should do a txg_wait_synced(). * * 0: the I/O has been initiated. * The caller should log this blkptr in the done callback. * It is possible that the I/O will fail, in which case * the error will be reported to the done callback and * propagated to pio from zio_done(). */ int dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db; objset_t *os = db->db_objset; dsl_dataset_t *ds = os->os_dsl_dataset; dbuf_dirty_record_t *dr, *dr_next; dmu_sync_arg_t *dsa; zbookmark_phys_t zb; zio_prop_t zp; dnode_t *dn; ASSERT(pio != NULL); ASSERT(txg != 0); SET_BOOKMARK(&zb, ds->ds_object, db->db.db_object, db->db_level, db->db_blkid); DB_DNODE_ENTER(db); dn = DB_DNODE(db); dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp); DB_DNODE_EXIT(db); /* * If we're frozen (running ziltest), we always need to generate a bp. */ if (txg > spa_freeze_txg(os->os_spa)) return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); /* * Grabbing db_mtx now provides a barrier between dbuf_sync_leaf() * and us. If we determine that this txg is not yet syncing, * but it begins to sync a moment later, that's OK because the * sync thread will block in dbuf_sync_leaf() until we drop db_mtx. */ mutex_enter(&db->db_mtx); if (txg <= spa_last_synced_txg(os->os_spa)) { /* * This txg has already synced. There's nothing to do. */ mutex_exit(&db->db_mtx); return (SET_ERROR(EEXIST)); } if (txg <= spa_syncing_txg(os->os_spa)) { /* * This txg is currently syncing, so we can't mess with * the dirty record anymore; just write a new log block. */ mutex_exit(&db->db_mtx); return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb)); } dr = dbuf_find_dirty_eq(db, txg); if (dr == NULL) { /* * There's no dr for this dbuf, so it must have been freed. * There's no need to log writes to freed blocks, so we're done. */ mutex_exit(&db->db_mtx); return (SET_ERROR(ENOENT)); } dr_next = list_next(&db->db_dirty_records, dr); ASSERT(dr_next == NULL || dr_next->dr_txg < txg); if (db->db_blkptr != NULL) { /* * We need to fill in zgd_bp with the current blkptr so that * the nopwrite code can check if we're writing the same * data that's already on disk. We can only nopwrite if we * are sure that after making the copy, db_blkptr will not * change until our i/o completes. We ensure this by * holding the db_mtx, and only allowing nopwrite if the * block is not already dirty (see below). This is verified * by dmu_sync_done(), which VERIFYs that the db_blkptr has * not changed. */ *zgd->zgd_bp = *db->db_blkptr; } /* * Assume the on-disk data is X, the current syncing data (in * txg - 1) is Y, and the current in-memory data is Z (currently * in dmu_sync). * * We usually want to perform a nopwrite if X and Z are the * same. However, if Y is different (i.e. the BP is going to * change before this write takes effect), then a nopwrite will * be incorrect - we would override with X, which could have * been freed when Y was written. * * (Note that this is not a concern when we are nop-writing from * syncing context, because X and Y must be identical, because * all previous txgs have been synced.) * * Therefore, we disable nopwrite if the current BP could change * before this TXG. There are two ways it could change: by * being dirty (dr_next is non-NULL), or by being freed * (dnode_block_freed()). This behavior is verified by * zio_done(), which VERIFYs that the override BP is identical * to the on-disk BP. */ DB_DNODE_ENTER(db); dn = DB_DNODE(db); if (dr_next != NULL || dnode_block_freed(dn, db->db_blkid)) zp.zp_nopwrite = B_FALSE; DB_DNODE_EXIT(db); ASSERT(dr->dr_txg == txg); if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC || dr->dt.dl.dr_override_state == DR_OVERRIDDEN) { /* * We have already issued a sync write for this buffer, * or this buffer has already been synced. It could not * have been dirtied since, or we would have cleared the state. */ mutex_exit(&db->db_mtx); return (SET_ERROR(EALREADY)); } ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN); dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC; mutex_exit(&db->db_mtx); dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP); dsa->dsa_dr = dr; dsa->dsa_done = done; dsa->dsa_zgd = zgd; dsa->dsa_tx = NULL; zio_nowait(arc_write(pio, os->os_spa, txg, zgd->zgd_bp, dr->dt.dl.dr_data, !DBUF_IS_CACHEABLE(db), dbuf_is_l2cacheable(db), &zp, dmu_sync_ready, NULL, dmu_sync_done, dsa, ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, &zb)); return (0); } int dmu_object_set_nlevels(objset_t *os, uint64_t object, int nlevels, dmu_tx_t *tx) { dnode_t *dn; int err; err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); err = dnode_set_nlevels(dn, nlevels, tx); dnode_rele(dn, FTAG); return (err); } int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs, dmu_tx_t *tx) { dnode_t *dn; int err; err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); err = dnode_set_blksz(dn, size, ibs, tx); dnode_rele(dn, FTAG); return (err); } int dmu_object_set_maxblkid(objset_t *os, uint64_t object, uint64_t maxblkid, dmu_tx_t *tx) { dnode_t *dn; int err; err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); dnode_new_blkid(dn, maxblkid, tx, B_FALSE, B_TRUE); rw_exit(&dn->dn_struct_rwlock); dnode_rele(dn, FTAG); return (0); } void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum, dmu_tx_t *tx) { dnode_t *dn; /* * Send streams include each object's checksum function. This * check ensures that the receiving system can understand the * checksum function transmitted. */ ASSERT3U(checksum, <, ZIO_CHECKSUM_LEGACY_FUNCTIONS); VERIFY0(dnode_hold(os, object, FTAG, &dn)); ASSERT3U(checksum, <, ZIO_CHECKSUM_FUNCTIONS); dn->dn_checksum = checksum; dnode_setdirty(dn, tx); dnode_rele(dn, FTAG); } void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress, dmu_tx_t *tx) { dnode_t *dn; /* * Send streams include each object's compression function. This * check ensures that the receiving system can understand the * compression function transmitted. */ ASSERT3U(compress, <, ZIO_COMPRESS_LEGACY_FUNCTIONS); VERIFY0(dnode_hold(os, object, FTAG, &dn)); dn->dn_compress = compress; dnode_setdirty(dn, tx); dnode_rele(dn, FTAG); } /* * When the "redundant_metadata" property is set to "most", only indirect * blocks of this level and higher will have an additional ditto block. */ static const int zfs_redundant_metadata_most_ditto_level = 2; void dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp) { dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET; boolean_t ismd = (level > 0 || DMU_OT_IS_METADATA(type) || (wp & WP_SPILL)); enum zio_checksum checksum = os->os_checksum; enum zio_compress compress = os->os_compress; uint8_t complevel = os->os_complevel; enum zio_checksum dedup_checksum = os->os_dedup_checksum; boolean_t dedup = B_FALSE; boolean_t nopwrite = B_FALSE; boolean_t dedup_verify = os->os_dedup_verify; boolean_t encrypt = B_FALSE; int copies = os->os_copies; /* * We maintain different write policies for each of the following * types of data: * 1. metadata * 2. preallocated blocks (i.e. level-0 blocks of a dump device) * 3. all other level 0 blocks */ if (ismd) { /* * XXX -- we should design a compression algorithm * that specializes in arrays of bps. */ compress = zio_compress_select(os->os_spa, ZIO_COMPRESS_ON, ZIO_COMPRESS_ON); /* * Metadata always gets checksummed. If the data * checksum is multi-bit correctable, and it's not a * ZBT-style checksum, then it's suitable for metadata * as well. Otherwise, the metadata checksum defaults * to fletcher4. */ if (!(zio_checksum_table[checksum].ci_flags & ZCHECKSUM_FLAG_METADATA) || (zio_checksum_table[checksum].ci_flags & ZCHECKSUM_FLAG_EMBEDDED)) checksum = ZIO_CHECKSUM_FLETCHER_4; switch (os->os_redundant_metadata) { case ZFS_REDUNDANT_METADATA_ALL: copies++; break; case ZFS_REDUNDANT_METADATA_MOST: if (level >= zfs_redundant_metadata_most_ditto_level || DMU_OT_IS_METADATA(type) || (wp & WP_SPILL)) copies++; break; case ZFS_REDUNDANT_METADATA_SOME: if (DMU_OT_IS_CRITICAL(type)) copies++; break; case ZFS_REDUNDANT_METADATA_NONE: break; } } else if (wp & WP_NOFILL) { ASSERT(level == 0); /* * If we're writing preallocated blocks, we aren't actually * writing them so don't set any policy properties. These * blocks are currently only used by an external subsystem * outside of zfs (i.e. dump) and not written by the zio * pipeline. */ compress = ZIO_COMPRESS_OFF; checksum = ZIO_CHECKSUM_OFF; } else { compress = zio_compress_select(os->os_spa, dn->dn_compress, compress); complevel = zio_complevel_select(os->os_spa, compress, complevel, complevel); checksum = (dedup_checksum == ZIO_CHECKSUM_OFF) ? zio_checksum_select(dn->dn_checksum, checksum) : dedup_checksum; /* * Determine dedup setting. If we are in dmu_sync(), * we won't actually dedup now because that's all * done in syncing context; but we do want to use the * dedup checksum. If the checksum is not strong * enough to ensure unique signatures, force * dedup_verify. */ if (dedup_checksum != ZIO_CHECKSUM_OFF) { dedup = (wp & WP_DMU_SYNC) ? B_FALSE : B_TRUE; if (!(zio_checksum_table[checksum].ci_flags & ZCHECKSUM_FLAG_DEDUP)) dedup_verify = B_TRUE; } /* * Enable nopwrite if we have secure enough checksum * algorithm (see comment in zio_nop_write) and * compression is enabled. We don't enable nopwrite if * dedup is enabled as the two features are mutually * exclusive. */ nopwrite = (!dedup && (zio_checksum_table[checksum].ci_flags & ZCHECKSUM_FLAG_NOPWRITE) && compress != ZIO_COMPRESS_OFF && zfs_nopwrite_enabled); } /* * All objects in an encrypted objset are protected from modification * via a MAC. Encrypted objects store their IV and salt in the last DVA * in the bp, so we cannot use all copies. Encrypted objects are also * not subject to nopwrite since writing the same data will still * result in a new ciphertext. Only encrypted blocks can be dedup'd * to avoid ambiguity in the dedup code since the DDT does not store * object types. */ if (os->os_encrypted && (wp & WP_NOFILL) == 0) { encrypt = B_TRUE; if (DMU_OT_IS_ENCRYPTED(type)) { copies = MIN(copies, SPA_DVAS_PER_BP - 1); nopwrite = B_FALSE; } else { dedup = B_FALSE; } if (level <= 0 && (type == DMU_OT_DNODE || type == DMU_OT_OBJSET)) { compress = ZIO_COMPRESS_EMPTY; } } zp->zp_compress = compress; zp->zp_complevel = complevel; zp->zp_checksum = checksum; zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type; zp->zp_level = level; zp->zp_copies = MIN(copies, spa_max_replication(os->os_spa)); zp->zp_dedup = dedup; zp->zp_dedup_verify = dedup && dedup_verify; zp->zp_nopwrite = nopwrite; zp->zp_encrypt = encrypt; zp->zp_byteorder = ZFS_HOST_BYTEORDER; memset(zp->zp_salt, 0, ZIO_DATA_SALT_LEN); memset(zp->zp_iv, 0, ZIO_DATA_IV_LEN); memset(zp->zp_mac, 0, ZIO_DATA_MAC_LEN); zp->zp_zpl_smallblk = DMU_OT_IS_FILE(zp->zp_type) ? os->os_zpl_special_smallblock : 0; ASSERT3U(zp->zp_compress, !=, ZIO_COMPRESS_INHERIT); } /* * Reports the location of data and holes in an object. In order to * accurately report holes all dirty data must be synced to disk. This * causes extremely poor performance when seeking for holes in a dirty file. * As a compromise, only provide hole data when the dnode is clean. When * a dnode is dirty report the dnode as having no holes by returning EBUSY * which is always safe to do. */ int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off) { dnode_t *dn; int restarted = 0, err; restart: err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); rw_enter(&dn->dn_struct_rwlock, RW_READER); if (dnode_is_dirty(dn)) { /* * If the zfs_dmu_offset_next_sync module option is enabled * then hole reporting has been requested. Dirty dnodes * must be synced to disk to accurately report holes. * * Provided a RL_READER rangelock spanning 0-UINT64_MAX is * held by the caller only a single restart will be required. * We tolerate callers which do not hold the rangelock by * returning EBUSY and not reporting holes after one restart. */ if (zfs_dmu_offset_next_sync) { rw_exit(&dn->dn_struct_rwlock); dnode_rele(dn, FTAG); if (restarted) return (SET_ERROR(EBUSY)); txg_wait_synced(dmu_objset_pool(os), 0); restarted = 1; goto restart; } err = SET_ERROR(EBUSY); } else { err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK | (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0); } rw_exit(&dn->dn_struct_rwlock); dnode_rele(dn, FTAG); return (err); } int dmu_read_l0_bps(objset_t *os, uint64_t object, uint64_t offset, uint64_t length, blkptr_t *bps, size_t *nbpsp) { dmu_buf_t **dbp, *dbuf; dmu_buf_impl_t *db; blkptr_t *bp; int error, numbufs; error = dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG, &numbufs, &dbp); if (error != 0) { if (error == ESRCH) { error = SET_ERROR(ENXIO); } return (error); } ASSERT3U(numbufs, <=, *nbpsp); for (int i = 0; i < numbufs; i++) { dbuf = dbp[i]; db = (dmu_buf_impl_t *)dbuf; mutex_enter(&db->db_mtx); if (!list_is_empty(&db->db_dirty_records)) { dbuf_dirty_record_t *dr; dr = list_head(&db->db_dirty_records); if (dr->dt.dl.dr_brtwrite) { /* * This is very special case where we clone a * block and in the same transaction group we * read its BP (most likely to clone the clone). */ bp = &dr->dt.dl.dr_overridden_by; } else { /* * The block was modified in the same * transaction group. */ mutex_exit(&db->db_mtx); error = SET_ERROR(EAGAIN); goto out; } } else { bp = db->db_blkptr; } mutex_exit(&db->db_mtx); if (bp == NULL) { /* * The block was created in this transaction group, * so it has no BP yet. */ error = SET_ERROR(EAGAIN); goto out; } /* * Make sure we clone only data blocks. */ if (BP_IS_METADATA(bp) && !BP_IS_HOLE(bp)) { error = SET_ERROR(EINVAL); goto out; } + /* + * If the block was allocated in transaction group that is not + * yet synced, we could clone it, but we couldn't write this + * operation into ZIL, or it may be impossible to replay, since + * the block may appear not yet allocated at that point. + */ + if (BP_PHYSICAL_BIRTH(bp) > spa_freeze_txg(os->os_spa)) { + error = SET_ERROR(EINVAL); + goto out; + } + if (BP_PHYSICAL_BIRTH(bp) > spa_last_synced_txg(os->os_spa)) { + error = SET_ERROR(EAGAIN); + goto out; + } + bps[i] = *bp; } *nbpsp = numbufs; out: dmu_buf_rele_array(dbp, numbufs, FTAG); return (error); } int dmu_brt_clone(objset_t *os, uint64_t object, uint64_t offset, uint64_t length, dmu_tx_t *tx, const blkptr_t *bps, size_t nbps) { spa_t *spa; dmu_buf_t **dbp, *dbuf; dmu_buf_impl_t *db; struct dirty_leaf *dl; dbuf_dirty_record_t *dr; const blkptr_t *bp; int error = 0, i, numbufs; spa = os->os_spa; VERIFY0(dmu_buf_hold_array(os, object, offset, length, FALSE, FTAG, &numbufs, &dbp)); ASSERT3U(nbps, ==, numbufs); /* * Before we start cloning make sure that the dbufs sizes match new BPs * sizes. If they don't, that's a no-go, as we are not able to shrink * dbufs. */ for (i = 0; i < numbufs; i++) { dbuf = dbp[i]; db = (dmu_buf_impl_t *)dbuf; bp = &bps[i]; ASSERT0(db->db_level); ASSERT(db->db_blkid != DMU_BONUS_BLKID); ASSERT(db->db_blkid != DMU_SPILL_BLKID); if (!BP_IS_HOLE(bp) && BP_GET_LSIZE(bp) != dbuf->db_size) { error = SET_ERROR(EXDEV); goto out; } } for (i = 0; i < numbufs; i++) { dbuf = dbp[i]; db = (dmu_buf_impl_t *)dbuf; bp = &bps[i]; ASSERT0(db->db_level); ASSERT(db->db_blkid != DMU_BONUS_BLKID); ASSERT(db->db_blkid != DMU_SPILL_BLKID); ASSERT(BP_IS_HOLE(bp) || dbuf->db_size == BP_GET_LSIZE(bp)); dmu_buf_will_clone(dbuf, tx); mutex_enter(&db->db_mtx); dr = list_head(&db->db_dirty_records); VERIFY(dr != NULL); ASSERT3U(dr->dr_txg, ==, tx->tx_txg); dl = &dr->dt.dl; dl->dr_overridden_by = *bp; dl->dr_brtwrite = B_TRUE; dl->dr_override_state = DR_OVERRIDDEN; if (BP_IS_HOLE(bp)) { dl->dr_overridden_by.blk_birth = 0; dl->dr_overridden_by.blk_phys_birth = 0; } else { dl->dr_overridden_by.blk_birth = dr->dr_txg; if (!BP_IS_EMBEDDED(bp)) { dl->dr_overridden_by.blk_phys_birth = BP_PHYSICAL_BIRTH(bp); } } mutex_exit(&db->db_mtx); /* * When data in embedded into BP there is no need to create * BRT entry as there is no data block. Just copy the BP as * it contains the data. */ if (!BP_IS_HOLE(bp) && !BP_IS_EMBEDDED(bp)) { brt_pending_add(spa, bp, tx); } } out: dmu_buf_rele_array(dbp, numbufs, FTAG); return (error); } void __dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) { dnode_phys_t *dnp = dn->dn_phys; doi->doi_data_block_size = dn->dn_datablksz; doi->doi_metadata_block_size = dn->dn_indblkshift ? 1ULL << dn->dn_indblkshift : 0; doi->doi_type = dn->dn_type; doi->doi_bonus_type = dn->dn_bonustype; doi->doi_bonus_size = dn->dn_bonuslen; doi->doi_dnodesize = dn->dn_num_slots << DNODE_SHIFT; doi->doi_indirection = dn->dn_nlevels; doi->doi_checksum = dn->dn_checksum; doi->doi_compress = dn->dn_compress; doi->doi_nblkptr = dn->dn_nblkptr; doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9; doi->doi_max_offset = (dn->dn_maxblkid + 1) * dn->dn_datablksz; doi->doi_fill_count = 0; for (int i = 0; i < dnp->dn_nblkptr; i++) doi->doi_fill_count += BP_GET_FILL(&dnp->dn_blkptr[i]); } void dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi) { rw_enter(&dn->dn_struct_rwlock, RW_READER); mutex_enter(&dn->dn_mtx); __dmu_object_info_from_dnode(dn, doi); mutex_exit(&dn->dn_mtx); rw_exit(&dn->dn_struct_rwlock); } /* * Get information on a DMU object. * If doi is NULL, just indicates whether the object exists. */ int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi) { dnode_t *dn; int err = dnode_hold(os, object, FTAG, &dn); if (err) return (err); if (doi != NULL) dmu_object_info_from_dnode(dn, doi); dnode_rele(dn, FTAG); return (0); } /* * As above, but faster; can be used when you have a held dbuf in hand. */ void dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; DB_DNODE_ENTER(db); dmu_object_info_from_dnode(DB_DNODE(db), doi); DB_DNODE_EXIT(db); } /* * Faster still when you only care about the size. */ void dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize, u_longlong_t *nblk512) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; dnode_t *dn; DB_DNODE_ENTER(db); dn = DB_DNODE(db); *blksize = dn->dn_datablksz; /* add in number of slots used for the dnode itself */ *nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >> SPA_MINBLOCKSHIFT) + dn->dn_num_slots; DB_DNODE_EXIT(db); } void dmu_object_dnsize_from_db(dmu_buf_t *db_fake, int *dnsize) { dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake; dnode_t *dn; DB_DNODE_ENTER(db); dn = DB_DNODE(db); *dnsize = dn->dn_num_slots << DNODE_SHIFT; DB_DNODE_EXIT(db); } void byteswap_uint64_array(void *vbuf, size_t size) { uint64_t *buf = vbuf; size_t count = size >> 3; int i; ASSERT((size & 7) == 0); for (i = 0; i < count; i++) buf[i] = BSWAP_64(buf[i]); } void byteswap_uint32_array(void *vbuf, size_t size) { uint32_t *buf = vbuf; size_t count = size >> 2; int i; ASSERT((size & 3) == 0); for (i = 0; i < count; i++) buf[i] = BSWAP_32(buf[i]); } void byteswap_uint16_array(void *vbuf, size_t size) { uint16_t *buf = vbuf; size_t count = size >> 1; int i; ASSERT((size & 1) == 0); for (i = 0; i < count; i++) buf[i] = BSWAP_16(buf[i]); } void byteswap_uint8_array(void *vbuf, size_t size) { (void) vbuf, (void) size; } void dmu_init(void) { abd_init(); zfs_dbgmsg_init(); sa_cache_init(); dmu_objset_init(); dnode_init(); zfetch_init(); dmu_tx_init(); l2arc_init(); arc_init(); dbuf_init(); } void dmu_fini(void) { arc_fini(); /* arc depends on l2arc, so arc must go first */ l2arc_fini(); dmu_tx_fini(); zfetch_fini(); dbuf_fini(); dnode_fini(); dmu_objset_fini(); sa_cache_fini(); zfs_dbgmsg_fini(); abd_fini(); } EXPORT_SYMBOL(dmu_bonus_hold); EXPORT_SYMBOL(dmu_bonus_hold_by_dnode); EXPORT_SYMBOL(dmu_buf_hold_array_by_bonus); EXPORT_SYMBOL(dmu_buf_rele_array); EXPORT_SYMBOL(dmu_prefetch); EXPORT_SYMBOL(dmu_free_range); EXPORT_SYMBOL(dmu_free_long_range); EXPORT_SYMBOL(dmu_free_long_object); EXPORT_SYMBOL(dmu_read); EXPORT_SYMBOL(dmu_read_by_dnode); EXPORT_SYMBOL(dmu_write); EXPORT_SYMBOL(dmu_write_by_dnode); EXPORT_SYMBOL(dmu_prealloc); EXPORT_SYMBOL(dmu_object_info); EXPORT_SYMBOL(dmu_object_info_from_dnode); EXPORT_SYMBOL(dmu_object_info_from_db); EXPORT_SYMBOL(dmu_object_size_from_db); EXPORT_SYMBOL(dmu_object_dnsize_from_db); EXPORT_SYMBOL(dmu_object_set_nlevels); EXPORT_SYMBOL(dmu_object_set_blocksize); EXPORT_SYMBOL(dmu_object_set_maxblkid); EXPORT_SYMBOL(dmu_object_set_checksum); EXPORT_SYMBOL(dmu_object_set_compress); EXPORT_SYMBOL(dmu_offset_next); EXPORT_SYMBOL(dmu_write_policy); EXPORT_SYMBOL(dmu_sync); EXPORT_SYMBOL(dmu_request_arcbuf); EXPORT_SYMBOL(dmu_return_arcbuf); EXPORT_SYMBOL(dmu_assign_arcbuf_by_dnode); EXPORT_SYMBOL(dmu_assign_arcbuf_by_dbuf); EXPORT_SYMBOL(dmu_buf_hold); EXPORT_SYMBOL(dmu_ot); ZFS_MODULE_PARAM(zfs, zfs_, nopwrite_enabled, INT, ZMOD_RW, "Enable NOP writes"); ZFS_MODULE_PARAM(zfs, zfs_, per_txg_dirty_frees_percent, UINT, ZMOD_RW, "Percentage of dirtied blocks from frees in one TXG"); ZFS_MODULE_PARAM(zfs, zfs_, dmu_offset_next_sync, INT, ZMOD_RW, "Enable forcing txg sync to find holes"); /* CSTYLED */ ZFS_MODULE_PARAM(zfs, , dmu_prefetch_max, UINT, ZMOD_RW, "Limit one prefetch call to this size"); diff --git a/module/zfs/zil.c b/module/zfs/zil.c index 7dfdaa081e8a..252d9a0493de 100644 --- a/module/zfs/zil.c +++ b/module/zfs/zil.c @@ -1,4242 +1,4260 @@ /* * 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 https://opensource.org/licenses/CDDL-1.0. * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * 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. */ static uint_t zfs_commit_timeout_pct = 10; /* * See zil.h for more information about these fields. */ static zil_kstat_values_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_normal_write", KSTAT_DATA_UINT64 }, { "zil_itx_metaslab_normal_alloc", KSTAT_DATA_UINT64 }, { "zil_itx_metaslab_slog_count", KSTAT_DATA_UINT64 }, { "zil_itx_metaslab_slog_bytes", KSTAT_DATA_UINT64 }, { "zil_itx_metaslab_slog_write", KSTAT_DATA_UINT64 }, { "zil_itx_metaslab_slog_alloc", KSTAT_DATA_UINT64 }, }; static zil_sums_t zil_sums_global; static kstat_t *zil_kstats_global; /* * 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. */ static 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. */ static uint64_t zil_slog_bulk = 64 * 1024 * 1024; static kmem_cache_t *zil_lwb_cache; static kmem_cache_t *zil_zcw_cache; static void zil_lwb_commit(zilog_t *zilog, lwb_t *lwb, itx_t *itx); static itx_t *zil_itx_clone(itx_t *oitx); 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 = TREE_CMP(DVA_GET_VDEV(dva1), DVA_GET_VDEV(dva2)); if (likely(cmp)) return (cmp); return (TREE_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; (void) random_get_pseudo_bytes((void *)&zc->zc_word[ZIL_ZC_GUID_0], sizeof (zc->zc_word[ZIL_ZC_GUID_0])); (void) random_get_pseudo_bytes((void *)&zc->zc_word[ZIL_ZC_GUID_1], sizeof (zc->zc_word[ZIL_ZC_GUID_1])); zc->zc_word[ZIL_ZC_OBJSET] = dmu_objset_id(zilog->zl_os); zc->zc_word[ZIL_ZC_SEQ] = 1ULL; } static int zil_kstats_global_update(kstat_t *ksp, int rw) { zil_kstat_values_t *zs = ksp->ks_data; ASSERT3P(&zil_stats, ==, zs); if (rw == KSTAT_WRITE) { return (SET_ERROR(EACCES)); } zil_kstat_values_update(zs, &zil_sums_global); return (0); } /* * 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, char **begin, char **end, arc_buf_t **abuf) { zio_flag_t zio_flags = ZIO_FLAG_CANFAIL; arc_flags_t aflags = ARC_FLAG_WAIT; 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]++; uint64_t size = BP_GET_LSIZE(bp); if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) { zil_chain_t *zilc = (*abuf)->b_data; char *lr = (char *)(zilc + 1); if (memcmp(&cksum, &zilc->zc_next_blk.blk_cksum, sizeof (cksum)) || zilc->zc_nused < sizeof (*zilc) || zilc->zc_nused > size) { error = SET_ERROR(ECKSUM); } else { *begin = lr; *end = lr + zilc->zc_nused - sizeof (*zilc); *nbp = zilc->zc_next_blk; } } else { char *lr = (*abuf)->b_data; zil_chain_t *zilc = (zil_chain_t *)(lr + size) - 1; if (memcmp(&cksum, &zilc->zc_next_blk.blk_cksum, sizeof (cksum)) || (zilc->zc_nused > (size - sizeof (*zilc)))) { error = SET_ERROR(ECKSUM); } else { *begin = lr; *end = lr + zilc->zc_nused; *nbp = zilc->zc_next_blk; } } } 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) { zio_flag_t 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) memset(wbuf, 0, 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; ASSERT3U(BP_GET_LSIZE(bp), !=, 0); 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) memcpy(wbuf, abuf->b_data, arc_buf_size(abuf)); arc_buf_destroy(abuf, &abuf); } return (error); } void zil_sums_init(zil_sums_t *zs) { wmsum_init(&zs->zil_commit_count, 0); wmsum_init(&zs->zil_commit_writer_count, 0); wmsum_init(&zs->zil_itx_count, 0); wmsum_init(&zs->zil_itx_indirect_count, 0); wmsum_init(&zs->zil_itx_indirect_bytes, 0); wmsum_init(&zs->zil_itx_copied_count, 0); wmsum_init(&zs->zil_itx_copied_bytes, 0); wmsum_init(&zs->zil_itx_needcopy_count, 0); wmsum_init(&zs->zil_itx_needcopy_bytes, 0); wmsum_init(&zs->zil_itx_metaslab_normal_count, 0); wmsum_init(&zs->zil_itx_metaslab_normal_bytes, 0); wmsum_init(&zs->zil_itx_metaslab_normal_write, 0); wmsum_init(&zs->zil_itx_metaslab_normal_alloc, 0); wmsum_init(&zs->zil_itx_metaslab_slog_count, 0); wmsum_init(&zs->zil_itx_metaslab_slog_bytes, 0); wmsum_init(&zs->zil_itx_metaslab_slog_write, 0); wmsum_init(&zs->zil_itx_metaslab_slog_alloc, 0); } void zil_sums_fini(zil_sums_t *zs) { wmsum_fini(&zs->zil_commit_count); wmsum_fini(&zs->zil_commit_writer_count); wmsum_fini(&zs->zil_itx_count); wmsum_fini(&zs->zil_itx_indirect_count); wmsum_fini(&zs->zil_itx_indirect_bytes); wmsum_fini(&zs->zil_itx_copied_count); wmsum_fini(&zs->zil_itx_copied_bytes); wmsum_fini(&zs->zil_itx_needcopy_count); wmsum_fini(&zs->zil_itx_needcopy_bytes); wmsum_fini(&zs->zil_itx_metaslab_normal_count); wmsum_fini(&zs->zil_itx_metaslab_normal_bytes); wmsum_fini(&zs->zil_itx_metaslab_normal_write); wmsum_fini(&zs->zil_itx_metaslab_normal_alloc); wmsum_fini(&zs->zil_itx_metaslab_slog_count); wmsum_fini(&zs->zil_itx_metaslab_slog_bytes); wmsum_fini(&zs->zil_itx_metaslab_slog_write); wmsum_fini(&zs->zil_itx_metaslab_slog_alloc); } void zil_kstat_values_update(zil_kstat_values_t *zs, zil_sums_t *zil_sums) { zs->zil_commit_count.value.ui64 = wmsum_value(&zil_sums->zil_commit_count); zs->zil_commit_writer_count.value.ui64 = wmsum_value(&zil_sums->zil_commit_writer_count); zs->zil_itx_count.value.ui64 = wmsum_value(&zil_sums->zil_itx_count); zs->zil_itx_indirect_count.value.ui64 = wmsum_value(&zil_sums->zil_itx_indirect_count); zs->zil_itx_indirect_bytes.value.ui64 = wmsum_value(&zil_sums->zil_itx_indirect_bytes); zs->zil_itx_copied_count.value.ui64 = wmsum_value(&zil_sums->zil_itx_copied_count); zs->zil_itx_copied_bytes.value.ui64 = wmsum_value(&zil_sums->zil_itx_copied_bytes); zs->zil_itx_needcopy_count.value.ui64 = wmsum_value(&zil_sums->zil_itx_needcopy_count); zs->zil_itx_needcopy_bytes.value.ui64 = wmsum_value(&zil_sums->zil_itx_needcopy_bytes); zs->zil_itx_metaslab_normal_count.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_normal_count); zs->zil_itx_metaslab_normal_bytes.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_normal_bytes); zs->zil_itx_metaslab_normal_write.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_normal_write); zs->zil_itx_metaslab_normal_alloc.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_normal_alloc); zs->zil_itx_metaslab_slog_count.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_slog_count); zs->zil_itx_metaslab_slog_bytes.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_slog_bytes); zs->zil_itx_metaslab_slog_write.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_slog_write); zs->zil_itx_metaslab_slog_alloc.value.ui64 = wmsum_value(&zil_sums->zil_itx_metaslab_slog_alloc); } /* * 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 = {{{{0}}}}; int error = 0; /* * 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. */ 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 *lrp, *end; arc_buf_t *abuf = 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, &lrp, &end, &abuf); if (error != 0) { if (abuf) arc_buf_destroy(abuf, &abuf); if (claimed) { char name[ZFS_MAX_DATASET_NAME_LEN]; dmu_objset_name(zilog->zl_os, name); cmn_err(CE_WARN, "ZFS read log block error %d, " "dataset %s, seq 0x%llx\n", error, name, (u_longlong_t)blk_seq); } break; } for (; lrp < end; lrp += reclen) { lr_t *lr = (lr_t *)lrp; reclen = lr->lrc_reclen; ASSERT3U(reclen, >=, sizeof (lr_t)); ASSERT3U(reclen, <=, end - lrp); if (lr->lrc_seq > claim_lr_seq) { arc_buf_destroy(abuf, &abuf); goto done; } error = parse_lr_func(zilog, lr, arg, txg); if (error != 0) { arc_buf_destroy(abuf, &abuf); goto done; } ASSERT3U(max_lr_seq, <, lr->lrc_seq); max_lr_seq = lr->lrc_seq; lr_count++; } arc_buf_destroy(abuf, &abuf); } 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; zil_bp_tree_fini(zilog); return (error); } static int zil_clear_log_block(zilog_t *zilog, const blkptr_t *bp, void *tx, uint64_t first_txg) { (void) tx; 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); } static int zil_noop_log_record(zilog_t *zilog, const lr_t *lrc, void *tx, uint64_t first_txg) { (void) zilog, (void) lrc, (void) tx, (void) first_txg; return (0); } static int zil_claim_log_block(zilog_t *zilog, const 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_write(zilog_t *zilog, const lr_t *lrc, void *tx, uint64_t first_txg) { lr_write_t *lr = (lr_write_t *)lrc; int error; ASSERT3U(lrc->lrc_reclen, >=, sizeof (*lr)); /* * 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)); } static int -zil_claim_clone_range(zilog_t *zilog, const lr_t *lrc, void *tx) +zil_claim_clone_range(zilog_t *zilog, const lr_t *lrc, void *tx, + uint64_t first_txg) { const lr_clone_range_t *lr = (const lr_clone_range_t *)lrc; const blkptr_t *bp; - spa_t *spa; + spa_t *spa = zilog->zl_spa; uint_t ii; ASSERT3U(lrc->lrc_reclen, >=, sizeof (*lr)); ASSERT3U(lrc->lrc_reclen, >=, offsetof(lr_clone_range_t, lr_bps[lr->lr_nbps])); if (tx == NULL) { return (0); } /* * XXX: Do we need to byteswap lr? */ - spa = zilog->zl_spa; - for (ii = 0; ii < lr->lr_nbps; ii++) { bp = &lr->lr_bps[ii]; /* - * When data in embedded into BP there is no need to create - * BRT entry as there is no data block. Just copy the BP as - * it contains the data. + * When data is embedded into the BP there is no need to create + * BRT entry as there is no data block. Just copy the BP as it + * contains the data. + */ + if (BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp)) + continue; + + /* + * We can not handle block pointers from the future, since they + * are not yet allocated. It should not normally happen, but + * just in case lets be safe and just stop here now instead of + * corrupting the pool. */ - if (!BP_IS_HOLE(bp) && !BP_IS_EMBEDDED(bp)) { + if (BP_PHYSICAL_BIRTH(bp) >= first_txg) + return (SET_ERROR(ENOENT)); + + /* + * Assert the block is really allocated before we reference it. + */ + metaslab_check_free(spa, bp); + } + + for (ii = 0; ii < lr->lr_nbps; ii++) { + bp = &lr->lr_bps[ii]; + if (!BP_IS_HOLE(bp) && !BP_IS_EMBEDDED(bp)) brt_pending_add(spa, bp, tx); - } } return (0); } static int zil_claim_log_record(zilog_t *zilog, const lr_t *lrc, void *tx, uint64_t first_txg) { switch (lrc->lrc_txtype) { case TX_WRITE: return (zil_claim_write(zilog, lrc, tx, first_txg)); case TX_CLONE_RANGE: - return (zil_claim_clone_range(zilog, lrc, tx)); + return (zil_claim_clone_range(zilog, lrc, tx, first_txg)); default: return (0); } } static int zil_free_log_block(zilog_t *zilog, const blkptr_t *bp, void *tx, uint64_t claim_txg) { (void) claim_txg; zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp); return (0); } static int zil_free_write(zilog_t *zilog, const lr_t *lrc, void *tx, uint64_t claim_txg) { lr_write_t *lr = (lr_write_t *)lrc; blkptr_t *bp = &lr->lr_blkptr; ASSERT3U(lrc->lrc_reclen, >=, sizeof (*lr)); /* * If we previously claimed it, we need to free it. */ if (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_free_clone_range(zilog_t *zilog, const lr_t *lrc, void *tx) { const lr_clone_range_t *lr = (const lr_clone_range_t *)lrc; const blkptr_t *bp; spa_t *spa; uint_t ii; ASSERT3U(lrc->lrc_reclen, >=, sizeof (*lr)); ASSERT3U(lrc->lrc_reclen, >=, offsetof(lr_clone_range_t, lr_bps[lr->lr_nbps])); if (tx == NULL) { return (0); } spa = zilog->zl_spa; for (ii = 0; ii < lr->lr_nbps; ii++) { bp = &lr->lr_bps[ii]; if (!BP_IS_HOLE(bp)) { zio_free(spa, dmu_tx_get_txg(tx), bp); } } return (0); } static int zil_free_log_record(zilog_t *zilog, const lr_t *lrc, void *tx, uint64_t claim_txg) { if (claim_txg == 0) { return (0); } switch (lrc->lrc_txtype) { case TX_WRITE: return (zil_free_write(zilog, lrc, tx, claim_txg)); case TX_CLONE_RANGE: return (zil_free_clone_range(zilog, lrc, tx)); default: 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 (TREE_CMP(v1, v2)); } /* * Allocate a new lwb. We may already have a block pointer for it, in which * case we get size and version from there. Or we may not yet, in which case * we choose them here and later make the block allocation match. */ static lwb_t * zil_alloc_lwb(zilog_t *zilog, int sz, blkptr_t *bp, boolean_t slog, uint64_t txg, lwb_state_t state) { lwb_t *lwb; lwb = kmem_cache_alloc(zil_lwb_cache, KM_SLEEP); lwb->lwb_zilog = zilog; if (bp) { lwb->lwb_blk = *bp; lwb->lwb_slim = (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2); sz = BP_GET_LSIZE(bp); } else { BP_ZERO(&lwb->lwb_blk); lwb->lwb_slim = (spa_version(zilog->zl_spa) >= SPA_VERSION_SLIM_ZIL); } lwb->lwb_slog = slog; lwb->lwb_error = 0; if (lwb->lwb_slim) { lwb->lwb_nmax = sz; lwb->lwb_nused = lwb->lwb_nfilled = sizeof (zil_chain_t); } else { lwb->lwb_nmax = sz - sizeof (zil_chain_t); lwb->lwb_nused = lwb->lwb_nfilled = 0; } lwb->lwb_sz = sz; lwb->lwb_state = state; lwb->lwb_buf = zio_buf_alloc(sz); lwb->lwb_child_zio = NULL; lwb->lwb_write_zio = NULL; lwb->lwb_root_zio = NULL; lwb->lwb_issued_timestamp = 0; lwb->lwb_issued_txg = 0; lwb->lwb_alloc_txg = txg; lwb->lwb_max_txg = 0; mutex_enter(&zilog->zl_lock); list_insert_tail(&zilog->zl_lwb_list, lwb); if (state != LWB_STATE_NEW) zilog->zl_last_lwb_opened = lwb; mutex_exit(&zilog->zl_lock); return (lwb); } static void zil_free_lwb(zilog_t *zilog, lwb_t *lwb) { ASSERT(MUTEX_HELD(&zilog->zl_lock)); ASSERT(lwb->lwb_state == LWB_STATE_NEW || lwb->lwb_state == LWB_STATE_FLUSH_DONE); ASSERT3P(lwb->lwb_child_zio, ==, NULL); ASSERT3P(lwb->lwb_write_zio, ==, NULL); ASSERT3P(lwb->lwb_root_zio, ==, NULL); ASSERT3U(lwb->lwb_alloc_txg, <=, spa_syncing_txg(zilog->zl_spa)); ASSERT3U(lwb->lwb_max_txg, <=, spa_syncing_txg(zilog->zl_spa)); VERIFY(list_is_empty(&lwb->lwb_itxs)); VERIFY(list_is_empty(&lwb->lwb_waiters)); ASSERT(avl_is_empty(&lwb->lwb_vdev_tree)); ASSERT(!MUTEX_HELD(&lwb->lwb_vdev_lock)); /* * 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(). */ static 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. */ static boolean_t __maybe_unused 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(). */ static 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); } /* * Its called in zil_commit context (zil_process_commit_list()/zil_create()). * It activates SPA_FEATURE_ZILSAXATTR feature, if its enabled. * Check dsl_dataset_feature_is_active to avoid txg_wait_synced() on every * zil_commit. */ static void zil_commit_activate_saxattr_feature(zilog_t *zilog) { dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); uint64_t txg = 0; dmu_tx_t *tx = NULL; if (spa_feature_is_enabled(zilog->zl_spa, SPA_FEATURE_ZILSAXATTR) && dmu_objset_type(zilog->zl_os) != DMU_OST_ZVOL && !dsl_dataset_feature_is_active(ds, SPA_FEATURE_ZILSAXATTR)) { tx = dmu_tx_create(zilog->zl_os); VERIFY0(dmu_tx_assign(tx, TXG_WAIT)); dsl_dataset_dirty(ds, tx); txg = dmu_tx_get_txg(tx); mutex_enter(&ds->ds_lock); ds->ds_feature_activation[SPA_FEATURE_ZILSAXATTR] = (void *)B_TRUE; mutex_exit(&ds->ds_lock); dmu_tx_commit(tx); txg_wait_synced(zilog->zl_dmu_pool, txg); } } /* * 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 slog = FALSE; dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); /* * 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); 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, 0, &blk, slog, txg, LWB_STATE_NEW); /* * 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) { /* * If "zilsaxattr" feature is enabled on zpool, then activate * it now when we're creating the ZIL chain. We can't wait with * this until we write the first xattr log record because we * need to wait for the feature activation to sync out. */ if (spa_feature_is_enabled(zilog->zl_spa, SPA_FEATURE_ZILSAXATTR) && dmu_objset_type(zilog->zl_os) != DMU_OST_ZVOL) { mutex_enter(&ds->ds_lock); ds->ds_feature_activation[SPA_FEATURE_ZILSAXATTR] = (void *)B_TRUE; mutex_exit(&ds->ds_lock); } dmu_tx_commit(tx); txg_wait_synced(zilog->zl_dmu_pool, txg); } else { /* * This branch covers the case where we enable the feature on a * zpool that has existing ZIL headers. */ zil_commit_activate_saxattr_feature(zilog); } IMPLY(spa_feature_is_enabled(zilog->zl_spa, SPA_FEATURE_ZILSAXATTR) && dmu_objset_type(zilog->zl_os) != DMU_OST_ZVOL, dsl_dataset_feature_is_active(ds, SPA_FEATURE_ZILSAXATTR)); ASSERT(error != 0 || memcmp(&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. * Return B_TRUE if there were any entries to replay. */ boolean_t 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 (B_FALSE); 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_remove_head(&zilog->zl_lwb_list)) != NULL) { if (lwb->lwb_buf != NULL) zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); if (!BP_IS_HOLE(&lwb->lwb_blk)) 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); return (B_TRUE); } 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. */ int zil_check_log_chain(dsl_pool_t *dp, dsl_dataset_t *ds, void *tx) { (void) dp; 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_issuer_lock while the lwb is open and zl_lock otherwise. * zl_issuer_lock also protects leaving the open state. * zcw_lwb setting is protected by zl_issuer_lock and state != * flush_done, which transition is protected by zl_lock. */ ASSERT(MUTEX_HELD(&lwb->lwb_zilog->zl_issuer_lock)); IMPLY(lwb->lwb_state != LWB_STATE_OPENED, MUTEX_HELD(&lwb->lwb_zilog->zl_lock)); ASSERT3S(lwb->lwb_state, !=, LWB_STATE_NEW); ASSERT3S(lwb->lwb_state, !=, LWB_STATE_FLUSH_DONE); ASSERT(!list_link_active(&zcw->zcw_node)); list_insert_tail(&lwb->lwb_waiters, zcw); ASSERT3P(zcw->zcw_lwb, ==, NULL); zcw->zcw_lwb = lwb; } /* * 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) { ASSERT(!list_link_active(&zcw->zcw_node)); list_insert_tail(nolwb, zcw); ASSERT3P(zcw->zcw_lwb, ==, NULL); } 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; ASSERT3S(lwb->lwb_state, !=, LWB_STATE_WRITE_DONE); ASSERT3S(lwb->lwb_state, !=, LWB_STATE_FLUSH_DONE); 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; zil_commit_waiter_t *zcw; itx_t *itx; spa_config_exit(zilog->zl_spa, SCL_STATE, lwb); hrtime_t t = gethrtime() - lwb->lwb_issued_timestamp; mutex_enter(&zilog->zl_lock); zilog->zl_last_lwb_latency = (zilog->zl_last_lwb_latency * 7 + t) / 8; 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_remove_head(&lwb->lwb_itxs)) != NULL) zil_itx_destroy(itx); while ((zcw = list_remove_head(&lwb->lwb_waiters)) != NULL) { mutex_enter(&zcw->zcw_lock); ASSERT3P(zcw->zcw_lwb, ==, lwb); zcw->zcw_lwb = NULL; /* * We expect any ZIO errors from child ZIOs to have been * propagated "up" to this specific LWB's root ZIO, in * order for this error handling to work correctly. This * includes ZIO errors from either this LWB's write or * flush, as well as any errors from other dependent LWBs * (e.g. a root LWB ZIO that might be a child of this LWB). * * With that said, it's important to note that LWB flush * errors are not propagated up to the LWB root ZIO. * This is incorrect behavior, and results in VDEV flush * errors not being handled correctly here. See the * comment above the call to "zio_flush" for details. */ 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); } uint64_t txg = lwb->lwb_issued_txg; /* Once we drop the lock, lwb may be freed by zil_sync(). */ mutex_exit(&zilog->zl_lock); mutex_enter(&zilog->zl_lwb_io_lock); ASSERT3U(zilog->zl_lwb_inflight[txg & TXG_MASK], >, 0); zilog->zl_lwb_inflight[txg & TXG_MASK]--; if (zilog->zl_lwb_inflight[txg & TXG_MASK] == 0) cv_broadcast(&zilog->zl_lwb_io_cv); mutex_exit(&zilog->zl_lwb_io_lock); } /* * Wait for the completion of all issued write/flush of that txg provided. * It guarantees zil_lwb_flush_vdevs_done() is called and returned. */ static void zil_lwb_flush_wait_all(zilog_t *zilog, uint64_t txg) { ASSERT3U(txg, ==, spa_syncing_txg(zilog->zl_spa)); mutex_enter(&zilog->zl_lwb_io_lock); while (zilog->zl_lwb_inflight[txg & TXG_MASK] > 0) cv_wait(&zilog->zl_lwb_io_cv, &zilog->zl_lwb_io_lock); mutex_exit(&zilog->zl_lwb_io_lock); #ifdef ZFS_DEBUG mutex_enter(&zilog->zl_lock); mutex_enter(&zilog->zl_lwb_io_lock); lwb_t *lwb = list_head(&zilog->zl_lwb_list); while (lwb != NULL) { if (lwb->lwb_issued_txg <= txg) { ASSERT(lwb->lwb_state != LWB_STATE_ISSUED); ASSERT(lwb->lwb_state != LWB_STATE_WRITE_DONE); IMPLY(lwb->lwb_issued_txg > 0, lwb->lwb_state == LWB_STATE_FLUSH_DONE); } IMPLY(lwb->lwb_state == LWB_STATE_WRITE_DONE || lwb->lwb_state == LWB_STATE_FLUSH_DONE, lwb->lwb_buf == NULL); lwb = list_next(&zilog->zl_lwb_list, lwb); } mutex_exit(&zilog->zl_lwb_io_lock); mutex_exit(&zilog->zl_lock); #endif } /* * 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); abd_free(zio->io_abd); zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); lwb->lwb_buf = NULL; mutex_enter(&zilog->zl_lock); ASSERT3S(lwb->lwb_state, ==, LWB_STATE_ISSUED); lwb->lwb_state = LWB_STATE_WRITE_DONE; lwb->lwb_child_zio = NULL; lwb->lwb_write_zio = NULL; /* * If nlwb is not yet issued, zil_lwb_set_zio_dependency() is not * called for it yet, and when it will be, it won't be able to make * its write ZIO a parent this ZIO. In such case we can not defer * our flushes or below may be a race between the done callbacks. */ nlwb = list_next(&zilog->zl_lwb_list, lwb); if (nlwb && nlwb->lwb_state != LWB_STATE_ISSUED) nlwb = NULL; 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. * * Additionally, we don't perform any further error handling at * this point (e.g. setting "zcw_zio_error" appropriately), as * we expect that to occur in "zil_lwb_flush_vdevs_done" (thus, * we expect any error seen here, to have been propagated to * that function). */ 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_is_empty(&lwb->lwb_waiters) && 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) { /* * The "ZIO_FLAG_DONT_PROPAGATE" is currently * always used within "zio_flush". This means, * any errors when flushing the vdev(s), will * (unfortunately) not be handled correctly, * since these "zio_flush" errors will not be * propagated up to "zil_lwb_flush_vdevs_done". */ zio_flush(lwb->lwb_root_zio, vd); } kmem_free(zv, sizeof (*zv)); } } /* * Build the 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). */ static void zil_lwb_set_zio_dependency(zilog_t *zilog, lwb_t *lwb) { ASSERT(MUTEX_HELD(&zilog->zl_lock)); lwb_t *prev_lwb = list_prev(&zilog->zl_lwb_list, lwb); if (prev_lwb == NULL || prev_lwb->lwb_state == LWB_STATE_FLUSH_DONE) return; /* * 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 (prev_lwb->lwb_state == LWB_STATE_ISSUED) { ASSERT3P(prev_lwb->lwb_write_zio, !=, NULL); zio_add_child(lwb->lwb_write_zio, prev_lwb->lwb_write_zio); } else { ASSERT3S(prev_lwb->lwb_state, ==, LWB_STATE_WRITE_DONE); } ASSERT3P(prev_lwb->lwb_root_zio, !=, NULL); zio_add_child(lwb->lwb_root_zio, prev_lwb->lwb_root_zio); } /* * This function's purpose is to "open" an lwb such that it is ready to * accept new itxs being committed to it. This function is idempotent; if * the passed in lwb has already been opened, it is essentially a no-op. */ static void zil_lwb_write_open(zilog_t *zilog, lwb_t *lwb) { ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); if (lwb->lwb_state != LWB_STATE_NEW) { ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED); return; } mutex_enter(&zilog->zl_lock); lwb->lwb_state = LWB_STATE_OPENED; zilog->zl_last_lwb_opened = lwb; mutex_exit(&zilog->zl_lock); } /* * 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. */ static const 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. */ static uint_t zil_maxblocksize = SPA_OLD_MAXBLOCKSIZE; /* * Close the log block for being issued and allocate the next one. * Has to be called under zl_issuer_lock to chain more lwbs. */ static lwb_t * zil_lwb_write_close(zilog_t *zilog, lwb_t *lwb, lwb_state_t state) { int i; ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED); lwb->lwb_state = LWB_STATE_CLOSED; /* * If there was an allocation failure then returned NULL will trigger * zil_commit_writer_stall() at the caller. This is inherently racy, * since allocation may not have happened yet. */ if (lwb->lwb_error != 0) return (NULL); /* * 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. */ uint64_t 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]); DTRACE_PROBE3(zil__block__size, zilog_t *, zilog, uint64_t, zil_blksz, uint64_t, zilog->zl_prev_blks[zilog->zl_prev_rotor]); zilog->zl_prev_rotor = (zilog->zl_prev_rotor + 1) & (ZIL_PREV_BLKS - 1); return (zil_alloc_lwb(zilog, zil_blksz, NULL, 0, 0, state)); } /* * Finalize previously closed block and issue the write zio. */ static void zil_lwb_write_issue(zilog_t *zilog, lwb_t *lwb) { spa_t *spa = zilog->zl_spa; zil_chain_t *zilc; boolean_t slog; zbookmark_phys_t zb; zio_priority_t prio; int error; ASSERT3S(lwb->lwb_state, ==, LWB_STATE_CLOSED); /* Actually fill the lwb with the data. */ for (itx_t *itx = list_head(&lwb->lwb_itxs); itx; itx = list_next(&lwb->lwb_itxs, itx)) zil_lwb_commit(zilog, lwb, itx); lwb->lwb_nused = lwb->lwb_nfilled; ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_nmax); lwb->lwb_root_zio = zio_root(spa, zil_lwb_flush_vdevs_done, lwb, ZIO_FLAG_CANFAIL); /* * The lwb is now ready to be issued, but it can be only if it already * got its block pointer allocated or the allocation has failed. * Otherwise leave it as-is, relying on some other thread to issue it * after allocating its block pointer via calling zil_lwb_write_issue() * for the previous lwb(s) in the chain. */ mutex_enter(&zilog->zl_lock); lwb->lwb_state = LWB_STATE_READY; if (BP_IS_HOLE(&lwb->lwb_blk) && lwb->lwb_error == 0) { mutex_exit(&zilog->zl_lock); return; } mutex_exit(&zilog->zl_lock); next_lwb: if (lwb->lwb_slim) zilc = (zil_chain_t *)lwb->lwb_buf; else zilc = (zil_chain_t *)(lwb->lwb_buf + lwb->lwb_nmax); int wsz = lwb->lwb_sz; if (lwb->lwb_error == 0) { abd_t *lwb_abd = abd_get_from_buf(lwb->lwb_buf, lwb->lwb_sz); if (!lwb->lwb_slog || zilog->zl_cur_used <= zil_slog_bulk) prio = ZIO_PRIORITY_SYNC_WRITE; else prio = ZIO_PRIORITY_ASYNC_WRITE; 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]); lwb->lwb_write_zio = zio_rewrite(lwb->lwb_root_zio, spa, 0, &lwb->lwb_blk, lwb_abd, lwb->lwb_sz, zil_lwb_write_done, lwb, prio, ZIO_FLAG_CANFAIL, &zb); zil_lwb_add_block(lwb, &lwb->lwb_blk); if (lwb->lwb_slim) { /* For Slim ZIL only write what is used. */ wsz = P2ROUNDUP_TYPED(lwb->lwb_nused, ZIL_MIN_BLKSZ, int); ASSERT3S(wsz, <=, lwb->lwb_sz); zio_shrink(lwb->lwb_write_zio, wsz); wsz = lwb->lwb_write_zio->io_size; } memset(lwb->lwb_buf + lwb->lwb_nused, 0, wsz - lwb->lwb_nused); zilc->zc_pad = 0; zilc->zc_nused = lwb->lwb_nused; zilc->zc_eck.zec_cksum = lwb->lwb_blk.blk_cksum; } else { /* * We can't write the lwb if there was an allocation failure, * so create a null zio instead just to maintain dependencies. */ lwb->lwb_write_zio = zio_null(lwb->lwb_root_zio, spa, NULL, zil_lwb_write_done, lwb, ZIO_FLAG_CANFAIL); lwb->lwb_write_zio->io_error = lwb->lwb_error; } if (lwb->lwb_child_zio) zio_add_child(lwb->lwb_write_zio, lwb->lwb_child_zio); /* * Open transaction to allocate the next block pointer. */ dmu_tx_t *tx = dmu_tx_create(zilog->zl_os); VERIFY0(dmu_tx_assign(tx, TXG_WAIT | TXG_NOTHROTTLE)); dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx); uint64_t txg = dmu_tx_get_txg(tx); /* * Allocate next the block pointer unless we are already in error. */ lwb_t *nlwb = list_next(&zilog->zl_lwb_list, lwb); blkptr_t *bp = &zilc->zc_next_blk; BP_ZERO(bp); error = lwb->lwb_error; if (error == 0) { error = zio_alloc_zil(spa, zilog->zl_os, txg, bp, nlwb->lwb_sz, &slog); } if (error == 0) { ASSERT3U(bp->blk_birth, ==, txg); BP_SET_CHECKSUM(bp, nlwb->lwb_slim ? ZIO_CHECKSUM_ZILOG2 : ZIO_CHECKSUM_ZILOG); bp->blk_cksum = lwb->lwb_blk.blk_cksum; bp->blk_cksum.zc_word[ZIL_ZC_SEQ]++; } /* * Reduce TXG open time by incrementing inflight counter and committing * the transaciton. zil_sync() will wait for it to return to zero. */ mutex_enter(&zilog->zl_lwb_io_lock); lwb->lwb_issued_txg = txg; zilog->zl_lwb_inflight[txg & TXG_MASK]++; zilog->zl_lwb_max_issued_txg = MAX(txg, zilog->zl_lwb_max_issued_txg); mutex_exit(&zilog->zl_lwb_io_lock); dmu_tx_commit(tx); spa_config_enter(spa, SCL_STATE, lwb, RW_READER); /* * We've completed all potentially blocking operations. Update the * nlwb and allow it proceed without possible lock order reversals. */ mutex_enter(&zilog->zl_lock); zil_lwb_set_zio_dependency(zilog, lwb); lwb->lwb_state = LWB_STATE_ISSUED; if (nlwb) { nlwb->lwb_blk = *bp; nlwb->lwb_error = error; nlwb->lwb_slog = slog; nlwb->lwb_alloc_txg = txg; if (nlwb->lwb_state != LWB_STATE_READY) nlwb = NULL; } mutex_exit(&zilog->zl_lock); if (lwb->lwb_slog) { ZIL_STAT_BUMP(zilog, zil_itx_metaslab_slog_count); ZIL_STAT_INCR(zilog, zil_itx_metaslab_slog_bytes, lwb->lwb_nused); ZIL_STAT_INCR(zilog, zil_itx_metaslab_slog_write, wsz); ZIL_STAT_INCR(zilog, zil_itx_metaslab_slog_alloc, BP_GET_LSIZE(&lwb->lwb_blk)); } else { ZIL_STAT_BUMP(zilog, zil_itx_metaslab_normal_count); ZIL_STAT_INCR(zilog, zil_itx_metaslab_normal_bytes, lwb->lwb_nused); ZIL_STAT_INCR(zilog, zil_itx_metaslab_normal_write, wsz); ZIL_STAT_INCR(zilog, zil_itx_metaslab_normal_alloc, BP_GET_LSIZE(&lwb->lwb_blk)); } lwb->lwb_issued_timestamp = gethrtime(); if (lwb->lwb_child_zio) zio_nowait(lwb->lwb_child_zio); zio_nowait(lwb->lwb_write_zio); zio_nowait(lwb->lwb_root_zio); /* * If nlwb was ready when we gave it the block pointer, * it is on us to issue it and possibly following ones. */ lwb = nlwb; if (lwb) goto next_lwb; } /* * Maximum amount of data that can be put into single log block. */ uint64_t zil_max_log_data(zilog_t *zilog, size_t hdrsize) { return (zilog->zl_max_block_size - sizeof (zil_chain_t) - hdrsize); } /* * Maximum amount of log space we agree to waste to reduce number of * WR_NEED_COPY chunks to reduce zl_get_data() overhead (~6%). */ static inline uint64_t zil_max_waste_space(zilog_t *zilog) { return (zil_max_log_data(zilog, sizeof (lr_write_t)) / 16); } /* * 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. Below that it is a tradeoff of additional memory copy * and possibly worse log space efficiency vs additional range lock/unlock. */ static uint_t zil_maxcopied = 7680; uint64_t zil_max_copied_data(zilog_t *zilog) { uint64_t max_data = zil_max_log_data(zilog, sizeof (lr_write_t)); return (MIN(max_data, zil_maxcopied)); } /* * Estimate space needed in the lwb for the itx. Allocate more lwbs or * split the itx as needed, but don't touch the actual transaction data. * Has to be called under zl_issuer_lock to call zil_lwb_write_close() * to chain more lwbs. */ static lwb_t * zil_lwb_assign(zilog_t *zilog, lwb_t *lwb, itx_t *itx, list_t *ilwbs) { itx_t *citx; lr_t *lr, *clr; lr_write_t *lrw; uint64_t dlen, dnow, lwb_sp, reclen, max_log_data; ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock)); ASSERT3P(lwb, !=, NULL); ASSERT3P(lwb->lwb_buf, !=, NULL); zil_lwb_write_open(zilog, lwb); lr = &itx->itx_lr; lrw = (lr_write_t *)lr; /* * 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 (lr->lrc_txtype == TX_COMMIT) { zil_commit_waiter_link_lwb(itx->itx_private, lwb); list_insert_tail(&lwb->lwb_itxs, itx); return (lwb); } reclen = lr->lrc_reclen; if (lr->lrc_txtype == TX_WRITE && itx->itx_wr_state == WR_NEED_COPY) { ASSERT3U(reclen, ==, sizeof (lr_write_t)); dlen = P2ROUNDUP_TYPED( lrw->lr_length, sizeof (uint64_t), uint64_t); } else { ASSERT3U(reclen, >=, sizeof (lr_t)); dlen = 0; } ASSERT3U(reclen, <=, zil_max_log_data(zilog, 0)); zilog->zl_cur_used += (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_nmax - lwb->lwb_nused; max_log_data = zil_max_log_data(zilog, sizeof (lr_write_t)); 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))) { list_insert_tail(ilwbs, lwb); lwb = zil_lwb_write_close(zilog, lwb, LWB_STATE_OPENED); if (lwb == NULL) return (NULL); lwb_sp = lwb->lwb_nmax - lwb->lwb_nused; } /* * There must be enough space in the log block to hold reclen. * For WR_COPIED, we need to fit the whole record in one block, * and reclen is the write record 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); if (dlen > dnow) { ASSERT3U(lr->lrc_txtype, ==, TX_WRITE); ASSERT3U(itx->itx_wr_state, ==, WR_NEED_COPY); citx = zil_itx_clone(itx); clr = &citx->itx_lr; lr_write_t *clrw = (lr_write_t *)clr; clrw->lr_length = dnow; lrw->lr_offset += dnow; lrw->lr_length -= dnow; } else { citx = itx; clr = lr; } /* * 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. */ clr->lrc_seq = ++zilog->zl_lr_seq; lwb->lwb_nused += reclen + dnow; ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_nmax); ASSERT0(P2PHASE(lwb->lwb_nused, sizeof (uint64_t))); zil_lwb_add_txg(lwb, lr->lrc_txg); list_insert_tail(&lwb->lwb_itxs, citx); dlen -= dnow; if (dlen > 0) { zilog->zl_cur_used += reclen; goto cont; } if (lr->lrc_txtype == TX_WRITE && lr->lrc_txg > spa_freeze_txg(zilog->zl_spa)) txg_wait_synced(zilog->zl_dmu_pool, lr->lrc_txg); return (lwb); } /* * Fill the actual transaction data into the lwb, following zil_lwb_assign(). * Does not require locking. */ static void zil_lwb_commit(zilog_t *zilog, lwb_t *lwb, itx_t *itx) { lr_t *lr, *lrb; lr_write_t *lrw, *lrwb; char *lr_buf; uint64_t dlen, reclen; lr = &itx->itx_lr; lrw = (lr_write_t *)lr; if (lr->lrc_txtype == TX_COMMIT) return; if (lr->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 = lr->lrc_reclen; ASSERT3U(reclen + dlen, <=, lwb->lwb_nused - lwb->lwb_nfilled); lr_buf = lwb->lwb_buf + lwb->lwb_nfilled; memcpy(lr_buf, lr, reclen); lrb = (lr_t *)lr_buf; /* Like lr, but inside lwb. */ lrwb = (lr_write_t *)lrb; /* Like lrw, but inside lwb. */ ZIL_STAT_BUMP(zilog, zil_itx_count); /* * If it's a write, fetch the data or get its blkptr as appropriate. */ if (lr->lrc_txtype == TX_WRITE) { if (itx->itx_wr_state == WR_COPIED) { ZIL_STAT_BUMP(zilog, zil_itx_copied_count); ZIL_STAT_INCR(zilog, zil_itx_copied_bytes, lrw->lr_length); } else { char *dbuf; int error; if (itx->itx_wr_state == WR_NEED_COPY) { dbuf = lr_buf + reclen; lrb->lrc_reclen += dlen; ZIL_STAT_BUMP(zilog, zil_itx_needcopy_count); ZIL_STAT_INCR(zilog, zil_itx_needcopy_bytes, dlen); } else { ASSERT3S(itx->itx_wr_state, ==, WR_INDIRECT); dbuf = NULL; ZIL_STAT_BUMP(zilog, zil_itx_indirect_count); ZIL_STAT_INCR(zilog, zil_itx_indirect_bytes, lrw->lr_length); if (lwb->lwb_child_zio == NULL) { lwb->lwb_child_zio = zio_null(NULL, zilog->zl_spa, NULL, NULL, NULL, ZIO_FLAG_CANFAIL); } } /* * The "lwb_child_zio" we pass in will become a child of * "lwb_write_zio", when one is created, so one will be * a parent of any zio's created by the "zl_get_data". * This way "lwb_write_zio" will first wait for children * block pointers before own writing, and then for their * writing completion before the vdev cache flushing. */ error = zilog->zl_get_data(itx->itx_private, itx->itx_gen, lrwb, dbuf, lwb, lwb->lwb_child_zio); if (dbuf != NULL && error == 0) { /* Zero any padding bytes in the last block. */ memset((char *)dbuf + lrwb->lr_length, 0, dlen - lrwb->lr_length); } /* * Typically, the only return values we should see from * ->zl_get_data() are 0, EIO, ENOENT, EEXIST or * EALREADY. However, it is also possible to see other * error values such as ENOSPC or EINVAL from * dmu_read() -> dnode_hold() -> dnode_hold_impl() or * ENXIO as well as a multitude of others from the * block layer through dmu_buf_hold() -> dbuf_read() * -> zio_wait(), as well as through dmu_read() -> * dnode_hold() -> dnode_hold_impl() -> dbuf_read() -> * zio_wait(). When these errors happen, we can assume * that neither an immediate write nor an indirect * write occurred, so we need to fall back to * txg_wait_synced(). This is unusual, so we print to * dmesg whenever one of these errors occurs. */ switch (error) { case 0: break; default: cmn_err(CE_WARN, "zil_lwb_commit() received " "unexpected error %d from ->zl_get_data()" ". Falling back to txg_wait_synced().", error); zfs_fallthrough; case EIO: txg_wait_synced(zilog->zl_dmu_pool, lr->lrc_txg); zfs_fallthrough; case ENOENT: zfs_fallthrough; case EEXIST: zfs_fallthrough; case EALREADY: return; } } } lwb->lwb_nfilled += reclen + dlen; ASSERT3S(lwb->lwb_nfilled, <=, lwb->lwb_nused); ASSERT0(P2PHASE(lwb->lwb_nfilled, sizeof (uint64_t))); } itx_t * zil_itx_create(uint64_t txtype, size_t olrsize) { size_t itxsize, lrsize; itx_t *itx; ASSERT3U(olrsize, >=, sizeof (lr_t)); lrsize = P2ROUNDUP_TYPED(olrsize, sizeof (uint64_t), size_t); ASSERT3U(lrsize, >=, olrsize); 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 */ memset((char *)&itx->itx_lr + olrsize, 0, lrsize - olrsize); itx->itx_sync = B_TRUE; /* default is synchronous */ itx->itx_callback = NULL; itx->itx_callback_data = NULL; itx->itx_size = itxsize; return (itx); } static itx_t * zil_itx_clone(itx_t *oitx) { ASSERT3U(oitx->itx_size, >=, sizeof (itx_t)); ASSERT3U(oitx->itx_size, ==, offsetof(itx_t, itx_lr) + oitx->itx_lr.lrc_reclen); itx_t *itx = zio_data_buf_alloc(oitx->itx_size); memcpy(itx, oitx, oitx->itx_size); itx->itx_callback = NULL; itx->itx_callback_data = NULL; return (itx); } void zil_itx_destroy(itx_t *itx) { ASSERT3U(itx->itx_size, >=, sizeof (itx_t)); ASSERT3U(itx->itx_lr.lrc_reclen, ==, itx->itx_size - offsetof(itx_t, itx_lr)); 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(void *arg) { itx_t *itx; list_t *list; avl_tree_t *t; void *cookie; itxs_t *itxs = arg; itx_async_node_t *ian; list = &itxs->i_sync_list; while ((itx = list_remove_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_assign(), 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); 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_remove_head(list)) != NULL) { /* 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 (TREE_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, ian_search; 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_search.ia_foid = oid; ian = avl_find(t, &ian_search, &where); if (ian != NULL) list_move_tail(&clean_list, &ian->ia_list); mutex_exit(&itxg->itxg_lock); } while ((itx = list_remove_head(&clean_list)) != NULL) { /* 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", (u_longlong_t)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, 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 uint64_t zil_get_commit_list(zilog_t *zilog) { uint64_t otxg, txg, wtxg = 0; 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_t *sync_list = &itxg->itxg_itxs->i_sync_list; if (unlikely(zilog->zl_suspend > 0)) { /* * ZIL was just suspended, but we lost the race. * Allow all earlier itxs to be committed, but ask * caller to do txg_wait_synced(txg) for any new. */ if (!list_is_empty(sync_list)) wtxg = MAX(wtxg, txg); } else { list_move_tail(commit_list, sync_list); } mutex_exit(&itxg->itxg_lock); } return (wtxg); } /* * Move the async itxs for a specified object to commit into sync lists. */ void zil_async_to_sync(zilog_t *zilog, uint64_t foid) { uint64_t otxg, txg; itx_async_node_t *ian, ian_search; 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_search.ia_foid = foid; ian = avl_find(t, &ian_search, &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); } 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); ASSERT(list_is_empty(&zilog->zl_lwb_list)); } static void zil_burst_done(zilog_t *zilog) { if (!list_is_empty(&zilog->zl_itx_commit_list) || zilog->zl_cur_used == 0) return; if (zilog->zl_parallel) zilog->zl_parallel--; zilog->zl_cur_used = 0; } /* * 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, zil_commit_waiter_t *zcw, list_t *ilwbs) { spa_t *spa = zilog->zl_spa; list_t nolwb_itxs; list_t nolwb_waiters; lwb_t *lwb, *plwb; 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_is_empty(&zilog->zl_itx_commit_list)) 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 { /* * Activate SPA_FEATURE_ZILSAXATTR for the cases where ZIL will * have already been created (zl_lwb_list not empty). */ zil_commit_activate_saxattr_feature(zilog); ASSERT(lwb->lwb_state == LWB_STATE_NEW || lwb->lwb_state == LWB_STATE_OPENED); /* * If the lwb is still opened, it means the workload is really * multi-threaded and we won the chance of write aggregation. * If it is not opened yet, but previous lwb is still not * flushed, it still means the workload is multi-threaded, but * there was too much time between the commits to aggregate, so * we try aggregation next times, but without too much hopes. */ if (lwb->lwb_state == LWB_STATE_OPENED) { zilog->zl_parallel = ZIL_BURSTS; } else if ((plwb = list_prev(&zilog->zl_lwb_list, lwb)) != NULL && plwb->lwb_state != LWB_STATE_FLUSH_DONE) { zilog->zl_parallel = MAX(zilog->zl_parallel, ZIL_BURSTS / 2); } } while ((itx = list_remove_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); } 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_assign(zilog, lwb, itx, ilwbs); if (lwb == NULL) { list_insert_tail(&nolwb_itxs, itx); } else if ((zcw->zcw_lwb != NULL && zcw->zcw_lwb != lwb) || zcw->zcw_done) { /* * Our lwb is done, leave the rest of * itx list to somebody else who care. */ zilog->zl_parallel = ZIL_BURSTS; break; } } 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. */ while ((lwb = list_remove_head(ilwbs)) != NULL) zil_lwb_write_issue(zilog, lwb); 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_remove_head(&nolwb_waiters)) != NULL) zil_commit_waiter_skip(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_remove_head(&nolwb_itxs)) != NULL) zil_itx_destroy(itx); } else { ASSERT(list_is_empty(&nolwb_waiters)); ASSERT3P(lwb, !=, NULL); ASSERT(lwb->lwb_state == LWB_STATE_NEW || lwb->lwb_state == LWB_STATE_OPENED); /* * At this point, the ZIL block pointed at by the "lwb" * variable is in "new" or "opened" state. * * If it's "new", 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 "opened", 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 by different thread and this lwb will be * closed by zil_lwb_assign(). This way, the lwb will 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, zil_commit_waiter() will close it and issue * the 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. */ if (lwb->lwb_state == LWB_STATE_OPENED && !zilog->zl_parallel) { list_insert_tail(ilwbs, lwb); lwb = zil_lwb_write_close(zilog, lwb, LWB_STATE_NEW); zil_burst_done(zilog); if (lwb == NULL) { while ((lwb = list_remove_head(ilwbs)) != NULL) zil_lwb_write_issue(zilog, lwb); zil_commit_writer_stall(zilog); } } } } /* * 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 uint64_t zil_commit_writer(zilog_t *zilog, zil_commit_waiter_t *zcw) { list_t ilwbs; lwb_t *lwb; uint64_t wtxg = 0; ASSERT(!MUTEX_HELD(&zilog->zl_lock)); ASSERT(spa_writeable(zilog->zl_spa)); list_create(&ilwbs, sizeof (lwb_t), offsetof(lwb_t, lwb_issue_node)); 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(zilog, zil_commit_writer_count); wtxg = zil_get_commit_list(zilog); zil_prune_commit_list(zilog); zil_process_commit_list(zilog, zcw, &ilwbs); out: mutex_exit(&zilog->zl_issuer_lock); while ((lwb = list_remove_head(&ilwbs)) != NULL) zil_lwb_write_issue(zilog, lwb); list_destroy(&ilwbs); return (wtxg); } 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_NEW); /* * 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_OPENED) return; /* * In order to call zil_lwb_write_close() 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) { mutex_exit(&zilog->zl_issuer_lock); return; } 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 CLOSED while we hold the zl_issuer_lock. The lwb * _can_ transition from CLOSED to DONE, but it's OK to race with * that transition since we treat the lwb the same, whether it's in * the CLOSED, ISSUED or DONE states. * * The important thing, is we treat the lwb differently depending on * if it's OPENED or CLOSED, and block any other threads that might * attempt to close/issue this lwb. For that reason we hold the * zl_issuer_lock when checking the lwb_state; we must not call * zil_lwb_write_close() if the lwb had already been closed/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_OPENED) { mutex_exit(&zilog->zl_issuer_lock); return; } /* * We do not need zcw_lock once we hold zl_issuer_lock and know lwb * is still open. But we have to drop it to avoid a deadlock in case * callback of zio issued by zil_lwb_write_issue() try to get it, * while zil_lwb_write_issue() is blocked on attempt to issue next * lwb it found in LWB_STATE_READY state. */ mutex_exit(&zcw->zcw_lock); /* * 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_close(zilog, lwb, LWB_STATE_NEW); ASSERT3S(lwb->lwb_state, ==, LWB_STATE_CLOSED); zil_burst_done(zilog); if (nlwb == NULL) { /* * When zil_lwb_write_close() 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. */ zil_lwb_write_issue(zilog, lwb); zil_commit_writer_stall(zilog); mutex_exit(&zilog->zl_issuer_lock); } else { mutex_exit(&zilog->zl_issuer_lock); zil_lwb_write_issue(zilog, lwb); } mutex_enter(&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_assign() * 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_NEW); 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. */ int rc = cv_timedwait_hires(&zcw->zcw_cv, &zcw->zcw_lock, wakeup, USEC2NSEC(1), CALLOUT_FLAG_ABSOLUTE); if (rc != -1 || 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_CLOSED || lwb->lwb_state == LWB_STATE_READY || 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); /* * 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)); 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 itx 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(zilog, 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); uint64_t wtxg = 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); } else if (wtxg != 0) { txg_wait_synced(zilog->zl_dmu_pool, wtxg); } 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; zil_lwb_flush_wait_all(zilog, txg); 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; dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); ASSERT(list_is_empty(&zilog->zl_lwb_list)); memset(zh, 0, sizeof (zil_header_t)); memset(zilog->zl_replayed_seq, 0, 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; } else { /* * A destroyed ZIL chain can't contain any TX_SETSAXATTR * records. So, deactivate the feature for this dataset. * We activate it again when we start a new ZIL chain. */ if (dsl_dataset_feature_is_active(ds, SPA_FEATURE_ZILSAXATTR)) dsl_dataset_deactivate_feature(ds, SPA_FEATURE_ZILSAXATTR, tx); } } while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) { zh->zh_log = lwb->lwb_blk; if (lwb->lwb_state != LWB_STATE_FLUSH_DONE || lwb->lwb_alloc_txg > txg || lwb->lwb_max_txg > txg) break; list_remove(&zilog->zl_lwb_list, lwb); if (!BP_IS_HOLE(&lwb->lwb_blk)) 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_is_empty(&zilog->zl_lwb_list)) BP_ZERO(&zh->zh_log); } mutex_exit(&zilog->zl_lock); } static int zil_lwb_cons(void *vbuf, void *unused, int kmflag) { (void) unused, (void) 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); } static void zil_lwb_dest(void *vbuf, void *unused) { (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_sums_init(&zil_sums_global); zil_kstats_global = kstat_create("zfs", 0, "zil", "misc", KSTAT_TYPE_NAMED, sizeof (zil_stats) / sizeof (kstat_named_t), KSTAT_FLAG_VIRTUAL); if (zil_kstats_global != NULL) { zil_kstats_global->ks_data = &zil_stats; zil_kstats_global->ks_update = zil_kstats_global_update; zil_kstats_global->ks_private = NULL; kstat_install(zil_kstats_global); } } void zil_fini(void) { kmem_cache_destroy(zil_zcw_cache); kmem_cache_destroy(zil_lwb_cache); if (zil_kstats_global != NULL) { kstat_delete(zil_kstats_global); zil_kstats_global = NULL; } zil_sums_fini(&zil_sums_global); } 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); mutex_init(&zilog->zl_lwb_io_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); cv_init(&zilog->zl_lwb_io_cv, 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); mutex_destroy(&zilog->zl_lwb_io_lock); cv_destroy(&zilog->zl_cv_suspend); cv_destroy(&zilog->zl_lwb_io_cv); kmem_free(zilog, sizeof (zilog_t)); } /* * Open an intent log. */ zilog_t * zil_open(objset_t *os, zil_get_data_t *get_data, zil_sums_t *zil_sums) { 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; zilog->zl_sums = zil_sums; 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 { ASSERT(list_is_empty(&zilog->zl_lwb_list)); ASSERT0(zilog->zl_dirty_max_txg); ASSERT3B(zilog_is_dirty(zilog), ==, B_FALSE); } mutex_enter(&zilog->zl_lock); txg = zilog->zl_dirty_max_txg; lwb = list_tail(&zilog->zl_lwb_list); if (lwb != NULL) { txg = MAX(txg, lwb->lwb_alloc_txg); txg = MAX(txg, lwb->lwb_max_txg); } mutex_exit(&zilog->zl_lock); /* * zl_lwb_max_issued_txg may be larger than lwb_max_txg. It depends * on the time when the dmu_tx transaction is assigned in * zil_lwb_write_issue(). */ mutex_enter(&zilog->zl_lwb_io_lock); txg = MAX(zilog->zl_lwb_max_issued_txg, txg); mutex_exit(&zilog->zl_lwb_io_lock); /* * We need to use txg_wait_synced() to wait until that txg is synced. * zil_sync() will guarantee all lwbs up to that txg have been * written out, flushed, and cleaned. */ 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, (u_longlong_t)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_remove_head(&zilog->zl_lwb_list); if (lwb != NULL) { ASSERT(list_is_empty(&zilog->zl_lwb_list)); ASSERT3S(lwb->lwb_state, ==, LWB_STATE_NEW); zio_buf_free(lwb->lwb_buf, lwb->lwb_sz); zil_free_lwb(zilog, lwb); } mutex_exit(&zilog->zl_lock); } static const 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, _CLOSED and _READY 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 *const *zr_replay; void *zr_arg; boolean_t zr_byteswap; char *zr_lr; } zil_replay_arg_t; static int zil_replay_error(zilog_t *zilog, const 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, const 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. */ memcpy(zr->zr_lr, 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); } static int zil_incr_blks(zilog_t *zilog, const blkptr_t *bp, void *arg, uint64_t claim_txg) { (void) bp, (void) arg, (void) claim_txg; zilog->zl_replay_blks++; return (0); } /* * If this dataset has a non-empty intent log, replay it and destroy it. * Return B_TRUE if there were any entries to replay. */ boolean_t zil_replay(objset_t *os, void *arg, zil_replay_func_t *const 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) { return (zil_destroy(zilog, B_TRUE)); } 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; return (B_TRUE); } 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); } int zil_reset(const char *osname, void *arg) { (void) arg; int 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); } 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); EXPORT_SYMBOL(zil_sums_init); EXPORT_SYMBOL(zil_sums_fini); EXPORT_SYMBOL(zil_kstat_values_update); ZFS_MODULE_PARAM(zfs, zfs_, commit_timeout_pct, UINT, ZMOD_RW, "ZIL block open timeout percentage"); ZFS_MODULE_PARAM(zfs_zil, zil_, replay_disable, INT, ZMOD_RW, "Disable intent logging replay"); ZFS_MODULE_PARAM(zfs_zil, zil_, nocacheflush, INT, ZMOD_RW, "Disable ZIL cache flushes"); ZFS_MODULE_PARAM(zfs_zil, zil_, slog_bulk, U64, ZMOD_RW, "Limit in bytes slog sync writes per commit"); ZFS_MODULE_PARAM(zfs_zil, zil_, maxblocksize, UINT, ZMOD_RW, "Limit in bytes of ZIL log block size"); ZFS_MODULE_PARAM(zfs_zil, zil_, maxcopied, UINT, ZMOD_RW, "Limit in bytes WR_COPIED size");