/* * 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, 2023, 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; if (newsize < 0 || newsize > db_fake->db_size) return (SET_ERROR(EINVAL)); DB_DNODE_ENTER(db); dn = DB_DNODE(db); if (dn->dn_bonus != db) { 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; if (!DMU_OT_IS_VALID(type)) return (SET_ERROR(EINVAL)); DB_DNODE_ENTER(db); dn = DB_DNODE(db); 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; dmu_object_type_t type; DB_DNODE_ENTER(db); type = DB_DNODE(db)->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; 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); err = dmu_spill_hold_by_dnode(DB_DNODE(db), 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_TYPED(offset, 1ULL << blkshift, uint64_t)) >> 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(&dn->dn_zfetch, 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(&dn->dn_zfetch, 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; int err; DB_DNODE_ENTER(db); err = dmu_buf_hold_array_by_dnode(DB_DNODE(db), 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 * is 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; if (dmu_prefetch_max == 0 || len == 0) { dmu_prefetch_dnode(os, object, pri); return; } if (dnode_hold(os, object, FTAG, &dn) != 0) return; dmu_prefetch_by_dnode(dn, level, offset, len, pri); dnode_rele(dn, FTAG); } void dmu_prefetch_by_dnode(dnode_t *dn, int64_t level, uint64_t offset, uint64_t len, zio_priority_t pri) { int64_t level2 = level; uint64_t start, end, start2, end2; /* * 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); } typedef struct { kmutex_t dpa_lock; kcondvar_t dpa_cv; uint64_t dpa_pending_io; } dmu_prefetch_arg_t; static void dmu_prefetch_done(void *arg, uint64_t level, uint64_t blkid, boolean_t issued) { (void) level; (void) blkid; (void)issued; dmu_prefetch_arg_t *dpa = arg; ASSERT0(level); mutex_enter(&dpa->dpa_lock); ASSERT3U(dpa->dpa_pending_io, >, 0); if (--dpa->dpa_pending_io == 0) cv_broadcast(&dpa->dpa_cv); mutex_exit(&dpa->dpa_lock); } static void dmu_prefetch_wait_by_dnode(dnode_t *dn, uint64_t offset, uint64_t len) { dmu_prefetch_arg_t dpa; mutex_init(&dpa.dpa_lock, NULL, MUTEX_DEFAULT, NULL); cv_init(&dpa.dpa_cv, NULL, CV_DEFAULT, NULL); rw_enter(&dn->dn_struct_rwlock, RW_READER); uint64_t start = dbuf_whichblock(dn, 0, offset); uint64_t end = dbuf_whichblock(dn, 0, offset + len - 1) + 1; dpa.dpa_pending_io = end - start; for (uint64_t blk = start; blk < end; blk++) { (void) dbuf_prefetch_impl(dn, 0, blk, ZIO_PRIORITY_ASYNC_READ, 0, dmu_prefetch_done, &dpa); } rw_exit(&dn->dn_struct_rwlock); /* wait for prefetch L0 reads to finish */ mutex_enter(&dpa.dpa_lock); while (dpa.dpa_pending_io > 0) { cv_wait(&dpa.dpa_cv, &dpa.dpa_lock); } mutex_exit(&dpa.dpa_lock); mutex_destroy(&dpa.dpa_lock); cv_destroy(&dpa.dpa_cv); } /* * Issue prefetch I/Os for the given L0 block range and wait for the I/O * to complete. This does not enforce dmu_prefetch_max and will prefetch * the entire range. The blocks are read from disk into the ARC but no * decompression occurs (i.e., the dbuf cache is not required). */ int dmu_prefetch_wait(objset_t *os, uint64_t object, uint64_t offset, uint64_t size) { dnode_t *dn; int err = 0; err = dnode_hold(os, object, FTAG, &dn); if (err != 0) return (err); /* * Chunk the requests (16 indirects worth) so that we can be interrupted */ uint64_t chunksize; if (dn->dn_indblkshift) { uint64_t nbps = bp_span_in_blocks(dn->dn_indblkshift, 1); chunksize = (nbps * 16) << dn->dn_datablkshift; } else { chunksize = dn->dn_datablksz; } while (size > 0) { uint64_t mylen = MIN(size, chunksize); dmu_prefetch_wait_by_dnode(dn, offset, mylen); offset += mylen; size -= mylen; if (issig()) { err = SET_ERROR(EINTR); break; } } dnode_rele(dn, FTAG); return (err); } /* * 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); /* dn_nlevels == 1 means we don't have any L1 blocks */ if (dn->dn_nlevels <= 1) { *l1blks = 0; *start = minimum; return (0); } /* * 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_TYPED(*start, iblkrange, uint64_t); } 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, B_FALSE); 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, B_FALSE); 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; int err; if (size == 0) return (0); DB_DNODE_ENTER(db); err = dmu_read_uio_dnode(DB_DNODE(db), 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); offset_t off = zfs_uio_offset(uio); bufoff = off - 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, B_TRUE); else dmu_buf_will_dirty(db, tx); 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, err)) { /* The fill was reverted. Undo any uio progress. */ zfs_uio_advance(uio, off - zfs_uio_offset(uio)); } 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; int err; if (size == 0) return (0); DB_DNODE_ENTER(db); err = dmu_write_uio_dnode(DB_DNODE(db), 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 */ static void dmu_cached_bps(spa_t *spa, blkptr_t *bps, uint_t nbps, uint64_t *l1sz, uint64_t *l2sz) { int cached_flags; if (bps == NULL) return; for (size_t blk_off = 0; blk_off < nbps; blk_off++) { blkptr_t *bp = &bps[blk_off]; if (BP_IS_HOLE(bp)) continue; cached_flags = arc_cached(spa, bp); if (cached_flags == 0) continue; if ((cached_flags & (ARC_CACHED_IN_L1 | ARC_CACHED_IN_L2)) == ARC_CACHED_IN_L2) *l2sz += BP_GET_LSIZE(bp); else *l1sz += BP_GET_LSIZE(bp); } } /* * Estimate DMU object cached size. */ int dmu_object_cached_size(objset_t *os, uint64_t object, uint64_t *l1sz, uint64_t *l2sz) { dnode_t *dn; dmu_object_info_t doi; int err = 0; *l1sz = *l2sz = 0; if (dnode_hold(os, object, FTAG, &dn) != 0) return (0); if (dn->dn_nlevels < 2) { dnode_rele(dn, FTAG); return (0); } dmu_object_info_from_dnode(dn, &doi); for (uint64_t off = 0; off < doi.doi_max_offset; off += dmu_prefetch_max) { /* dbuf_read doesn't prefetch L1 blocks. */ dmu_prefetch_by_dnode(dn, 1, off, dmu_prefetch_max, ZIO_PRIORITY_SYNC_READ); } /* * Hold all valid L1 blocks, asking ARC the status of each BP * contained in each such L1 block. */ uint_t nbps = bp_span_in_blocks(dn->dn_indblkshift, 1); uint64_t l1blks = 1 + (dn->dn_maxblkid / nbps); rw_enter(&dn->dn_struct_rwlock, RW_READER); for (uint64_t blk = 0; blk < l1blks; blk++) { dmu_buf_impl_t *db = NULL; if (issig()) { /* * On interrupt, get out, and bubble up EINTR */ err = EINTR; break; } /* * If we get an i/o error here, the L1 can't be read, * and nothing under it could be cached, so we just * continue. Ignoring the error from dbuf_hold_impl * or from dbuf_read is then a reasonable choice. */ err = dbuf_hold_impl(dn, 1, blk, B_TRUE, B_FALSE, FTAG, &db); if (err != 0) { /* * ignore error and continue */ err = 0; continue; } err = dbuf_read(db, NULL, DB_RF_CANFAIL); if (err == 0) { dmu_cached_bps(dmu_objset_spa(os), db->db.db_data, nbps, l1sz, l2sz); } /* * error may be ignored, and we continue */ err = 0; dbuf_rele(db, FTAG); } rw_exit(&dn->dn_struct_rwlock); dnode_rele(dn, FTAG); return (err); } /* * 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); rw_exit(&dn->dn_struct_rwlock); if (db == NULL) return (SET_ERROR(EIO)); /* * 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 *db = (dmu_buf_impl_t *)handle; DB_DNODE_ENTER(db); err = dmu_assign_arcbuf_by_dnode(DB_DNODE(db), offset, buf, tx); DB_DNODE_EXIT(db); 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) && BP_GET_LOGICAL_BIRTH(&dr->dt.dl.dr_overridden_by) == 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(BP_GET_LOGICAL_BIRTH(zio->io_bp) == 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; 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); dmu_write_policy(os, DB_DNODE(db), 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. */ if (dr_next != NULL) { zp.zp_nopwrite = B_FALSE; } else { DB_DNODE_ENTER(db); if (dnode_block_freed(DB_DNODE(db), 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; zp->zp_storage_type = dn ? dn->dn_storage_type : DMU_OT_NONE; 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 file size was increased, but the block was never * written, otherwise we would either have the block * pointer or the dirty record and would not get here. * It is effectively a hole, so report it as such. */ BP_ZERO(&bps[i]); continue; } /* * 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_GET_BIRTH(bp) > spa_freeze_txg(os->os_spa)) { error = SET_ERROR(EINVAL); goto out; } if (BP_GET_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; if (!BP_IS_HOLE(bp) || BP_GET_LOGICAL_BIRTH(bp) != 0) { if (!BP_IS_EMBEDDED(bp)) { BP_SET_BIRTH(&dl->dr_overridden_by, dr->dr_txg, BP_GET_BIRTH(bp)); } else { BP_SET_LOGICAL_BIRTH(&dl->dr_overridden_by, dr->dr_txg); } } dl->dr_brtwrite = B_TRUE; dl->dr_override_state = DR_OVERRIDDEN; 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; DB_DNODE_ENTER(db); *dnsize = DB_DNODE(db)->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_prefetch_by_dnode); EXPORT_SYMBOL(dmu_prefetch_dnode); 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");