/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include static int free_range_compar(const void *node1, const void *node2); static kmem_cache_t *dnode_cache; static dnode_phys_t dnode_phys_zero; int zfs_default_bs = SPA_MINBLOCKSHIFT; int zfs_default_ibs = DN_MAX_INDBLKSHIFT; /* ARGSUSED */ static int dnode_cons(void *arg, void *unused, int kmflag) { int i; dnode_t *dn = arg; bzero(dn, sizeof (dnode_t)); rw_init(&dn->dn_struct_rwlock, NULL, RW_DEFAULT, NULL); mutex_init(&dn->dn_mtx, NULL, MUTEX_DEFAULT, NULL); mutex_init(&dn->dn_dbufs_mtx, NULL, MUTEX_DEFAULT, NULL); cv_init(&dn->dn_notxholds, NULL, CV_DEFAULT, NULL); refcount_create(&dn->dn_holds); refcount_create(&dn->dn_tx_holds); for (i = 0; i < TXG_SIZE; i++) { avl_create(&dn->dn_ranges[i], free_range_compar, sizeof (free_range_t), offsetof(struct free_range, fr_node)); list_create(&dn->dn_dirty_records[i], sizeof (dbuf_dirty_record_t), offsetof(dbuf_dirty_record_t, dr_dirty_node)); } list_create(&dn->dn_dbufs, sizeof (dmu_buf_impl_t), offsetof(dmu_buf_impl_t, db_link)); return (0); } /* ARGSUSED */ static void dnode_dest(void *arg, void *unused) { int i; dnode_t *dn = arg; rw_destroy(&dn->dn_struct_rwlock); mutex_destroy(&dn->dn_mtx); mutex_destroy(&dn->dn_dbufs_mtx); cv_destroy(&dn->dn_notxholds); refcount_destroy(&dn->dn_holds); refcount_destroy(&dn->dn_tx_holds); for (i = 0; i < TXG_SIZE; i++) { avl_destroy(&dn->dn_ranges[i]); list_destroy(&dn->dn_dirty_records[i]); } list_destroy(&dn->dn_dbufs); } void dnode_init(void) { dnode_cache = kmem_cache_create("dnode_t", sizeof (dnode_t), 0, dnode_cons, dnode_dest, NULL, NULL, NULL, 0); } void dnode_fini(void) { kmem_cache_destroy(dnode_cache); } #ifdef ZFS_DEBUG void dnode_verify(dnode_t *dn) { int drop_struct_lock = FALSE; ASSERT(dn->dn_phys); ASSERT(dn->dn_objset); ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); if (!(zfs_flags & ZFS_DEBUG_DNODE_VERIFY)) return; if (!RW_WRITE_HELD(&dn->dn_struct_rwlock)) { rw_enter(&dn->dn_struct_rwlock, RW_READER); drop_struct_lock = TRUE; } if (dn->dn_phys->dn_type != DMU_OT_NONE || dn->dn_allocated_txg != 0) { int i; ASSERT3U(dn->dn_indblkshift, >=, 0); ASSERT3U(dn->dn_indblkshift, <=, SPA_MAXBLOCKSHIFT); if (dn->dn_datablkshift) { ASSERT3U(dn->dn_datablkshift, >=, SPA_MINBLOCKSHIFT); ASSERT3U(dn->dn_datablkshift, <=, SPA_MAXBLOCKSHIFT); ASSERT3U(1<dn_datablkshift, ==, dn->dn_datablksz); } ASSERT3U(dn->dn_nlevels, <=, 30); ASSERT3U(dn->dn_type, <=, DMU_OT_NUMTYPES); ASSERT3U(dn->dn_nblkptr, >=, 1); ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); ASSERT3U(dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); ASSERT3U(dn->dn_datablksz, ==, dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); ASSERT3U(ISP2(dn->dn_datablksz), ==, dn->dn_datablkshift != 0); ASSERT3U((dn->dn_nblkptr - 1) * sizeof (blkptr_t) + dn->dn_bonuslen, <=, DN_MAX_BONUSLEN); for (i = 0; i < TXG_SIZE; i++) { ASSERT3U(dn->dn_next_nlevels[i], <=, dn->dn_nlevels); } } if (dn->dn_phys->dn_type != DMU_OT_NONE) ASSERT3U(dn->dn_phys->dn_nlevels, <=, dn->dn_nlevels); ASSERT(DMU_OBJECT_IS_SPECIAL(dn->dn_object) || dn->dn_dbuf != NULL); if (dn->dn_dbuf != NULL) { ASSERT3P(dn->dn_phys, ==, (dnode_phys_t *)dn->dn_dbuf->db.db_data + (dn->dn_object % (dn->dn_dbuf->db.db_size >> DNODE_SHIFT))); } if (drop_struct_lock) rw_exit(&dn->dn_struct_rwlock); } #endif void dnode_byteswap(dnode_phys_t *dnp) { uint64_t *buf64 = (void*)&dnp->dn_blkptr; int i; if (dnp->dn_type == DMU_OT_NONE) { bzero(dnp, sizeof (dnode_phys_t)); return; } dnp->dn_datablkszsec = BSWAP_16(dnp->dn_datablkszsec); dnp->dn_bonuslen = BSWAP_16(dnp->dn_bonuslen); dnp->dn_maxblkid = BSWAP_64(dnp->dn_maxblkid); dnp->dn_used = BSWAP_64(dnp->dn_used); /* * dn_nblkptr is only one byte, so it's OK to read it in either * byte order. We can't read dn_bouslen. */ ASSERT(dnp->dn_indblkshift <= SPA_MAXBLOCKSHIFT); ASSERT(dnp->dn_nblkptr <= DN_MAX_NBLKPTR); for (i = 0; i < dnp->dn_nblkptr * sizeof (blkptr_t)/8; i++) buf64[i] = BSWAP_64(buf64[i]); /* * OK to check dn_bonuslen for zero, because it won't matter if * we have the wrong byte order. This is necessary because the * dnode dnode is smaller than a regular dnode. */ if (dnp->dn_bonuslen != 0) { /* * Note that the bonus length calculated here may be * longer than the actual bonus buffer. This is because * we always put the bonus buffer after the last block * pointer (instead of packing it against the end of the * dnode buffer). */ int off = (dnp->dn_nblkptr-1) * sizeof (blkptr_t); size_t len = DN_MAX_BONUSLEN - off; ASSERT3U(dnp->dn_bonustype, <, DMU_OT_NUMTYPES); dmu_ot[dnp->dn_bonustype].ot_byteswap(dnp->dn_bonus + off, len); } /* Swap SPILL block if we have one */ if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) byteswap_uint64_array(&dnp->dn_spill, sizeof (blkptr_t)); } void dnode_buf_byteswap(void *vbuf, size_t size) { dnode_phys_t *buf = vbuf; int i; ASSERT3U(sizeof (dnode_phys_t), ==, (1<>= DNODE_SHIFT; for (i = 0; i < size; i++) { dnode_byteswap(buf); buf++; } } static int free_range_compar(const void *node1, const void *node2) { const free_range_t *rp1 = node1; const free_range_t *rp2 = node2; if (rp1->fr_blkid < rp2->fr_blkid) return (-1); else if (rp1->fr_blkid > rp2->fr_blkid) return (1); else return (0); } void dnode_setbonuslen(dnode_t *dn, int newsize, dmu_tx_t *tx) { ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); dnode_setdirty(dn, tx); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); ASSERT3U(newsize, <=, DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t)); dn->dn_bonuslen = newsize; if (newsize == 0) dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = DN_ZERO_BONUSLEN; else dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; rw_exit(&dn->dn_struct_rwlock); } void dnode_setbonus_type(dnode_t *dn, dmu_object_type_t newtype, dmu_tx_t *tx) { ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); dnode_setdirty(dn, tx); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); dn->dn_bonustype = newtype; dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; rw_exit(&dn->dn_struct_rwlock); } void dnode_rm_spill(dnode_t *dn, dmu_tx_t *tx) { ASSERT3U(refcount_count(&dn->dn_holds), >=, 1); ASSERT(RW_WRITE_HELD(&dn->dn_struct_rwlock)); dnode_setdirty(dn, tx); dn->dn_rm_spillblk[tx->tx_txg&TXG_MASK] = DN_KILL_SPILLBLK; dn->dn_have_spill = B_FALSE; } static void dnode_setdblksz(dnode_t *dn, int size) { ASSERT3U(P2PHASE(size, SPA_MINBLOCKSIZE), ==, 0); ASSERT3U(size, <=, SPA_MAXBLOCKSIZE); ASSERT3U(size, >=, SPA_MINBLOCKSIZE); ASSERT3U(size >> SPA_MINBLOCKSHIFT, <, 1<<(sizeof (dn->dn_phys->dn_datablkszsec) * 8)); dn->dn_datablksz = size; dn->dn_datablkszsec = size >> SPA_MINBLOCKSHIFT; dn->dn_datablkshift = ISP2(size) ? highbit(size - 1) : 0; } static dnode_t * dnode_create(objset_t *os, dnode_phys_t *dnp, dmu_buf_impl_t *db, uint64_t object) { dnode_t *dn = kmem_cache_alloc(dnode_cache, KM_SLEEP); (void) dnode_cons(dn, NULL, 0); /* XXX */ dn->dn_objset = os; dn->dn_object = object; dn->dn_dbuf = db; dn->dn_phys = dnp; if (dnp->dn_datablkszsec) dnode_setdblksz(dn, dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT); dn->dn_indblkshift = dnp->dn_indblkshift; dn->dn_nlevels = dnp->dn_nlevels; dn->dn_type = dnp->dn_type; dn->dn_nblkptr = dnp->dn_nblkptr; dn->dn_checksum = dnp->dn_checksum; dn->dn_compress = dnp->dn_compress; dn->dn_bonustype = dnp->dn_bonustype; dn->dn_bonuslen = dnp->dn_bonuslen; dn->dn_maxblkid = dnp->dn_maxblkid; dn->dn_have_spill = ((dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) != 0); dn->dn_id_flags = 0; dmu_zfetch_init(&dn->dn_zfetch, dn); ASSERT(dn->dn_phys->dn_type < DMU_OT_NUMTYPES); mutex_enter(&os->os_lock); list_insert_head(&os->os_dnodes, dn); mutex_exit(&os->os_lock); arc_space_consume(sizeof (dnode_t), ARC_SPACE_OTHER); return (dn); } static void dnode_destroy(dnode_t *dn) { objset_t *os = dn->dn_objset; #ifdef ZFS_DEBUG int i; for (i = 0; i < TXG_SIZE; i++) { ASSERT(!list_link_active(&dn->dn_dirty_link[i])); ASSERT(NULL == list_head(&dn->dn_dirty_records[i])); ASSERT(0 == avl_numnodes(&dn->dn_ranges[i])); } ASSERT(NULL == list_head(&dn->dn_dbufs)); #endif ASSERT((dn->dn_id_flags & DN_ID_NEW_EXIST) == 0); mutex_enter(&os->os_lock); list_remove(&os->os_dnodes, dn); mutex_exit(&os->os_lock); if (dn->dn_dirtyctx_firstset) { kmem_free(dn->dn_dirtyctx_firstset, 1); dn->dn_dirtyctx_firstset = NULL; } dmu_zfetch_rele(&dn->dn_zfetch); if (dn->dn_bonus) { mutex_enter(&dn->dn_bonus->db_mtx); dbuf_evict(dn->dn_bonus); dn->dn_bonus = NULL; } kmem_cache_free(dnode_cache, dn); arc_space_return(sizeof (dnode_t), ARC_SPACE_OTHER); } void dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) { int i; if (blocksize == 0) blocksize = 1 << zfs_default_bs; else if (blocksize > SPA_MAXBLOCKSIZE) blocksize = SPA_MAXBLOCKSIZE; else blocksize = P2ROUNDUP(blocksize, SPA_MINBLOCKSIZE); if (ibs == 0) ibs = zfs_default_ibs; ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT); dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d\n", dn->dn_objset, dn->dn_object, tx->tx_txg, blocksize, ibs); ASSERT(dn->dn_type == DMU_OT_NONE); ASSERT(bcmp(dn->dn_phys, &dnode_phys_zero, sizeof (dnode_phys_t)) == 0); ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE); ASSERT(ot != DMU_OT_NONE); ASSERT3U(ot, <, DMU_OT_NUMTYPES); ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || (bonustype == DMU_OT_SA && bonuslen == 0) || (bonustype != DMU_OT_NONE && bonuslen != 0)); ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); ASSERT(dn->dn_type == DMU_OT_NONE); ASSERT3U(dn->dn_maxblkid, ==, 0); ASSERT3U(dn->dn_allocated_txg, ==, 0); ASSERT3U(dn->dn_assigned_txg, ==, 0); ASSERT(refcount_is_zero(&dn->dn_tx_holds)); ASSERT3U(refcount_count(&dn->dn_holds), <=, 1); ASSERT3P(list_head(&dn->dn_dbufs), ==, NULL); for (i = 0; i < TXG_SIZE; i++) { ASSERT3U(dn->dn_next_nlevels[i], ==, 0); ASSERT3U(dn->dn_next_indblkshift[i], ==, 0); ASSERT3U(dn->dn_next_bonuslen[i], ==, 0); ASSERT3U(dn->dn_next_bonustype[i], ==, 0); ASSERT3U(dn->dn_rm_spillblk[i], ==, 0); ASSERT3U(dn->dn_next_blksz[i], ==, 0); ASSERT(!list_link_active(&dn->dn_dirty_link[i])); ASSERT3P(list_head(&dn->dn_dirty_records[i]), ==, NULL); ASSERT3U(avl_numnodes(&dn->dn_ranges[i]), ==, 0); } dn->dn_type = ot; dnode_setdblksz(dn, blocksize); dn->dn_indblkshift = ibs; dn->dn_nlevels = 1; if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ dn->dn_nblkptr = 1; else dn->dn_nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); dn->dn_bonustype = bonustype; dn->dn_bonuslen = bonuslen; dn->dn_checksum = ZIO_CHECKSUM_INHERIT; dn->dn_compress = ZIO_COMPRESS_INHERIT; dn->dn_dirtyctx = 0; dn->dn_free_txg = 0; if (dn->dn_dirtyctx_firstset) { kmem_free(dn->dn_dirtyctx_firstset, 1); dn->dn_dirtyctx_firstset = NULL; } dn->dn_allocated_txg = tx->tx_txg; dn->dn_id_flags = 0; dnode_setdirty(dn, tx); dn->dn_next_indblkshift[tx->tx_txg & TXG_MASK] = ibs; dn->dn_next_bonuslen[tx->tx_txg & TXG_MASK] = dn->dn_bonuslen; dn->dn_next_bonustype[tx->tx_txg & TXG_MASK] = dn->dn_bonustype; dn->dn_next_blksz[tx->tx_txg & TXG_MASK] = dn->dn_datablksz; } void dnode_reallocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) { int nblkptr; ASSERT3U(blocksize, >=, SPA_MINBLOCKSIZE); ASSERT3U(blocksize, <=, SPA_MAXBLOCKSIZE); ASSERT3U(blocksize % SPA_MINBLOCKSIZE, ==, 0); ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT || dmu_tx_private_ok(tx)); ASSERT(tx->tx_txg != 0); ASSERT((bonustype == DMU_OT_NONE && bonuslen == 0) || (bonustype != DMU_OT_NONE && bonuslen != 0) || (bonustype == DMU_OT_SA && bonuslen == 0)); ASSERT3U(bonustype, <, DMU_OT_NUMTYPES); ASSERT3U(bonuslen, <=, DN_MAX_BONUSLEN); /* clean up any unreferenced dbufs */ dnode_evict_dbufs(dn); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); dnode_setdirty(dn, tx); if (dn->dn_datablksz != blocksize) { /* change blocksize */ ASSERT(dn->dn_maxblkid == 0 && (BP_IS_HOLE(&dn->dn_phys->dn_blkptr[0]) || dnode_block_freed(dn, 0))); dnode_setdblksz(dn, blocksize); dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = blocksize; } if (dn->dn_bonuslen != bonuslen) dn->dn_next_bonuslen[tx->tx_txg&TXG_MASK] = bonuslen; if (bonustype == DMU_OT_SA) /* Maximize bonus space for SA */ nblkptr = 1; else nblkptr = 1 + ((DN_MAX_BONUSLEN - bonuslen) >> SPA_BLKPTRSHIFT); if (dn->dn_bonustype != bonustype) dn->dn_next_bonustype[tx->tx_txg&TXG_MASK] = bonustype; if (dn->dn_nblkptr != nblkptr) dn->dn_next_nblkptr[tx->tx_txg&TXG_MASK] = nblkptr; if (dn->dn_phys->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { dbuf_rm_spill(dn, tx); dnode_rm_spill(dn, tx); } rw_exit(&dn->dn_struct_rwlock); /* change type */ dn->dn_type = ot; /* change bonus size and type */ mutex_enter(&dn->dn_mtx); dn->dn_bonustype = bonustype; dn->dn_bonuslen = bonuslen; dn->dn_nblkptr = nblkptr; dn->dn_checksum = ZIO_CHECKSUM_INHERIT; dn->dn_compress = ZIO_COMPRESS_INHERIT; ASSERT3U(dn->dn_nblkptr, <=, DN_MAX_NBLKPTR); /* fix up the bonus db_size */ if (dn->dn_bonus) { dn->dn_bonus->db.db_size = DN_MAX_BONUSLEN - (dn->dn_nblkptr-1) * sizeof (blkptr_t); ASSERT(dn->dn_bonuslen <= dn->dn_bonus->db.db_size); } dn->dn_allocated_txg = tx->tx_txg; mutex_exit(&dn->dn_mtx); } void dnode_special_close(dnode_t *dn) { /* * Wait for final references to the dnode to clear. This can * only happen if the arc is asyncronously evicting state that * has a hold on this dnode while we are trying to evict this * dnode. */ while (refcount_count(&dn->dn_holds) > 0) delay(1); dnode_destroy(dn); } dnode_t * dnode_special_open(objset_t *os, dnode_phys_t *dnp, uint64_t object) { dnode_t *dn = dnode_create(os, dnp, NULL, object); DNODE_VERIFY(dn); return (dn); } static void dnode_buf_pageout(dmu_buf_t *db, void *arg) { dnode_t **children_dnodes = arg; int i; int epb = db->db_size >> DNODE_SHIFT; for (i = 0; i < epb; i++) { dnode_t *dn = children_dnodes[i]; int n; if (dn == NULL) continue; #ifdef ZFS_DEBUG /* * If there are holds on this dnode, then there should * be holds on the dnode's containing dbuf as well; thus * it wouldn't be eligable for eviction and this function * would not have been called. */ ASSERT(refcount_is_zero(&dn->dn_holds)); ASSERT(list_head(&dn->dn_dbufs) == NULL); ASSERT(refcount_is_zero(&dn->dn_tx_holds)); for (n = 0; n < TXG_SIZE; n++) ASSERT(!list_link_active(&dn->dn_dirty_link[n])); #endif children_dnodes[i] = NULL; dnode_destroy(dn); } kmem_free(children_dnodes, epb * sizeof (dnode_t *)); } /* * errors: * EINVAL - invalid object number. * EIO - i/o error. * succeeds even for free dnodes. */ int dnode_hold_impl(objset_t *os, uint64_t object, int flag, void *tag, dnode_t **dnp) { int epb, idx, err; int drop_struct_lock = FALSE; int type; uint64_t blk; dnode_t *mdn, *dn; dmu_buf_impl_t *db; dnode_t **children_dnodes; /* * If you are holding the spa config lock as writer, you shouldn't * be asking the DMU to do *anything* unless it's the root pool * which may require us to read from the root filesystem while * holding some (not all) of the locks as writer. */ ASSERT(spa_config_held(os->os_spa, SCL_ALL, RW_WRITER) == 0 || (spa_is_root(os->os_spa) && spa_config_held(os->os_spa, SCL_STATE, RW_WRITER) && !spa_config_held(os->os_spa, SCL_ZIO, RW_WRITER))); if (object == DMU_USERUSED_OBJECT || object == DMU_GROUPUSED_OBJECT) { dn = (object == DMU_USERUSED_OBJECT) ? os->os_userused_dnode : os->os_groupused_dnode; if (dn == NULL) return (ENOENT); type = dn->dn_type; if ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) return (ENOENT); if ((flag & DNODE_MUST_BE_FREE) && type != DMU_OT_NONE) return (EEXIST); DNODE_VERIFY(dn); (void) refcount_add(&dn->dn_holds, tag); *dnp = dn; return (0); } if (object == 0 || object >= DN_MAX_OBJECT) return (EINVAL); mdn = os->os_meta_dnode; DNODE_VERIFY(mdn); if (!RW_WRITE_HELD(&mdn->dn_struct_rwlock)) { rw_enter(&mdn->dn_struct_rwlock, RW_READER); drop_struct_lock = TRUE; } blk = dbuf_whichblock(mdn, object * sizeof (dnode_phys_t)); db = dbuf_hold(mdn, blk, FTAG); if (drop_struct_lock) rw_exit(&mdn->dn_struct_rwlock); if (db == NULL) return (EIO); err = dbuf_read(db, NULL, DB_RF_CANFAIL); if (err) { dbuf_rele(db, FTAG); return (err); } ASSERT3U(db->db.db_size, >=, 1<db.db_size >> DNODE_SHIFT; idx = object & (epb-1); children_dnodes = dmu_buf_get_user(&db->db); if (children_dnodes == NULL) { dnode_t **winner; children_dnodes = kmem_zalloc(epb * sizeof (dnode_t *), KM_SLEEP); if (winner = dmu_buf_set_user(&db->db, children_dnodes, NULL, dnode_buf_pageout)) { kmem_free(children_dnodes, epb * sizeof (dnode_t *)); children_dnodes = winner; } } if ((dn = children_dnodes[idx]) == NULL) { dnode_phys_t *dnp = (dnode_phys_t *)db->db.db_data+idx; dnode_t *winner; dn = dnode_create(os, dnp, db, object); winner = atomic_cas_ptr(&children_dnodes[idx], NULL, dn); if (winner != NULL) { dnode_destroy(dn); dn = winner; } } mutex_enter(&dn->dn_mtx); type = dn->dn_type; if (dn->dn_free_txg || ((flag & DNODE_MUST_BE_ALLOCATED) && type == DMU_OT_NONE) || ((flag & DNODE_MUST_BE_FREE) && (type != DMU_OT_NONE || (dn->dn_id_flags & DN_ID_SYNC)))) { mutex_exit(&dn->dn_mtx); dbuf_rele(db, FTAG); return (type == DMU_OT_NONE ? ENOENT : EEXIST); } if (flag & DNODE_MUST_BE_FREE) { ASSERT(refcount_is_zero(&dn->dn_holds)); ASSERT(!(dn->dn_id_flags & DN_ID_SYNC)); } mutex_exit(&dn->dn_mtx); if (refcount_add(&dn->dn_holds, tag) == 1) dbuf_add_ref(db, dn); DNODE_VERIFY(dn); ASSERT3P(dn->dn_dbuf, ==, db); ASSERT3U(dn->dn_object, ==, object); dbuf_rele(db, FTAG); *dnp = dn; return (0); } /* * Return held dnode if the object is allocated, NULL if not. */ int dnode_hold(objset_t *os, uint64_t object, void *tag, dnode_t **dnp) { return (dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED, tag, dnp)); } /* * Can only add a reference if there is already at least one * reference on the dnode. Returns FALSE if unable to add a * new reference. */ boolean_t dnode_add_ref(dnode_t *dn, void *tag) { mutex_enter(&dn->dn_mtx); if (refcount_is_zero(&dn->dn_holds)) { mutex_exit(&dn->dn_mtx); return (FALSE); } VERIFY(1 < refcount_add(&dn->dn_holds, tag)); mutex_exit(&dn->dn_mtx); return (TRUE); } void dnode_rele(dnode_t *dn, void *tag) { uint64_t refs; mutex_enter(&dn->dn_mtx); refs = refcount_remove(&dn->dn_holds, tag); mutex_exit(&dn->dn_mtx); /* NOTE: the DNODE_DNODE does not have a dn_dbuf */ if (refs == 0 && dn->dn_dbuf) dbuf_rele(dn->dn_dbuf, dn); } void dnode_setdirty(dnode_t *dn, dmu_tx_t *tx) { objset_t *os = dn->dn_objset; uint64_t txg = tx->tx_txg; if (DMU_OBJECT_IS_SPECIAL(dn->dn_object)) { dsl_dataset_dirty(os->os_dsl_dataset, tx); return; } DNODE_VERIFY(dn); #ifdef ZFS_DEBUG mutex_enter(&dn->dn_mtx); ASSERT(dn->dn_phys->dn_type || dn->dn_allocated_txg); /* ASSERT(dn->dn_free_txg == 0 || dn->dn_free_txg >= txg); */ mutex_exit(&dn->dn_mtx); #endif /* * Determine old uid/gid when necessary */ dmu_objset_userquota_get_ids(dn, B_TRUE, tx); mutex_enter(&os->os_lock); /* * If we are already marked dirty, we're done. */ if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) { mutex_exit(&os->os_lock); return; } ASSERT(!refcount_is_zero(&dn->dn_holds) || list_head(&dn->dn_dbufs)); ASSERT(dn->dn_datablksz != 0); ASSERT3U(dn->dn_next_bonuslen[txg&TXG_MASK], ==, 0); ASSERT3U(dn->dn_next_blksz[txg&TXG_MASK], ==, 0); ASSERT3U(dn->dn_next_bonustype[txg&TXG_MASK], ==, 0); dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n", dn->dn_object, txg); if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) { list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn); } else { list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn); } mutex_exit(&os->os_lock); /* * The dnode maintains a hold on its containing dbuf as * long as there are holds on it. Each instantiated child * dbuf maintaines a hold on the dnode. When the last child * drops its hold, the dnode will drop its hold on the * containing dbuf. We add a "dirty hold" here so that the * dnode will hang around after we finish processing its * children. */ VERIFY(dnode_add_ref(dn, (void *)(uintptr_t)tx->tx_txg)); (void) dbuf_dirty(dn->dn_dbuf, tx); dsl_dataset_dirty(os->os_dsl_dataset, tx); } void dnode_free(dnode_t *dn, dmu_tx_t *tx) { int txgoff = tx->tx_txg & TXG_MASK; dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg); /* we should be the only holder... hopefully */ /* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */ mutex_enter(&dn->dn_mtx); if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) { mutex_exit(&dn->dn_mtx); return; } dn->dn_free_txg = tx->tx_txg; mutex_exit(&dn->dn_mtx); /* * If the dnode is already dirty, it needs to be moved from * the dirty list to the free list. */ mutex_enter(&dn->dn_objset->os_lock); if (list_link_active(&dn->dn_dirty_link[txgoff])) { list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn); list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn); mutex_exit(&dn->dn_objset->os_lock); } else { mutex_exit(&dn->dn_objset->os_lock); dnode_setdirty(dn, tx); } } /* * Try to change the block size for the indicated dnode. This can only * succeed if there are no blocks allocated or dirty beyond first block */ int dnode_set_blksz(dnode_t *dn, uint64_t size, int ibs, dmu_tx_t *tx) { dmu_buf_impl_t *db, *db_next; int err; if (size == 0) size = SPA_MINBLOCKSIZE; if (size > SPA_MAXBLOCKSIZE) size = SPA_MAXBLOCKSIZE; else size = P2ROUNDUP(size, SPA_MINBLOCKSIZE); if (ibs == dn->dn_indblkshift) ibs = 0; if (size >> SPA_MINBLOCKSHIFT == dn->dn_datablkszsec && ibs == 0) return (0); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); /* Check for any allocated blocks beyond the first */ if (dn->dn_phys->dn_maxblkid != 0) goto fail; mutex_enter(&dn->dn_dbufs_mtx); for (db = list_head(&dn->dn_dbufs); db; db = db_next) { db_next = list_next(&dn->dn_dbufs, db); if (db->db_blkid != 0 && db->db_blkid != DMU_BONUS_BLKID && db->db_blkid != DMU_SPILL_BLKID) { mutex_exit(&dn->dn_dbufs_mtx); goto fail; } } mutex_exit(&dn->dn_dbufs_mtx); if (ibs && dn->dn_nlevels != 1) goto fail; /* resize the old block */ err = dbuf_hold_impl(dn, 0, 0, TRUE, FTAG, &db); if (err == 0) dbuf_new_size(db, size, tx); else if (err != ENOENT) goto fail; dnode_setdblksz(dn, size); dnode_setdirty(dn, tx); dn->dn_next_blksz[tx->tx_txg&TXG_MASK] = size; if (ibs) { dn->dn_indblkshift = ibs; dn->dn_next_indblkshift[tx->tx_txg&TXG_MASK] = ibs; } /* rele after we have fixed the blocksize in the dnode */ if (db) dbuf_rele(db, FTAG); rw_exit(&dn->dn_struct_rwlock); return (0); fail: rw_exit(&dn->dn_struct_rwlock); return (ENOTSUP); } /* read-holding callers must not rely on the lock being continuously held */ void dnode_new_blkid(dnode_t *dn, uint64_t blkid, dmu_tx_t *tx, boolean_t have_read) { uint64_t txgoff = tx->tx_txg & TXG_MASK; int epbs, new_nlevels; uint64_t sz; ASSERT(blkid != DMU_BONUS_BLKID); ASSERT(have_read ? RW_READ_HELD(&dn->dn_struct_rwlock) : RW_WRITE_HELD(&dn->dn_struct_rwlock)); /* * if we have a read-lock, check to see if we need to do any work * before upgrading to a write-lock. */ if (have_read) { if (blkid <= dn->dn_maxblkid) return; if (!rw_tryupgrade(&dn->dn_struct_rwlock)) { rw_exit(&dn->dn_struct_rwlock); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); } } if (blkid <= dn->dn_maxblkid) goto out; dn->dn_maxblkid = blkid; /* * Compute the number of levels necessary to support the new maxblkid. */ new_nlevels = 1; epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; for (sz = dn->dn_nblkptr; sz <= blkid && sz >= dn->dn_nblkptr; sz <<= epbs) new_nlevels++; if (new_nlevels > dn->dn_nlevels) { int old_nlevels = dn->dn_nlevels; dmu_buf_impl_t *db; list_t *list; dbuf_dirty_record_t *new, *dr, *dr_next; dn->dn_nlevels = new_nlevels; ASSERT3U(new_nlevels, >, dn->dn_next_nlevels[txgoff]); dn->dn_next_nlevels[txgoff] = new_nlevels; /* dirty the left indirects */ db = dbuf_hold_level(dn, old_nlevels, 0, FTAG); ASSERT(db != NULL); new = dbuf_dirty(db, tx); dbuf_rele(db, FTAG); /* transfer the dirty records to the new indirect */ mutex_enter(&dn->dn_mtx); mutex_enter(&new->dt.di.dr_mtx); list = &dn->dn_dirty_records[txgoff]; for (dr = list_head(list); dr; dr = dr_next) { dr_next = list_next(&dn->dn_dirty_records[txgoff], dr); if (dr->dr_dbuf->db_level != new_nlevels-1 && dr->dr_dbuf->db_blkid != DMU_BONUS_BLKID && dr->dr_dbuf->db_blkid != DMU_SPILL_BLKID) { ASSERT(dr->dr_dbuf->db_level == old_nlevels-1); list_remove(&dn->dn_dirty_records[txgoff], dr); list_insert_tail(&new->dt.di.dr_children, dr); dr->dr_parent = new; } } mutex_exit(&new->dt.di.dr_mtx); mutex_exit(&dn->dn_mtx); } out: if (have_read) rw_downgrade(&dn->dn_struct_rwlock); } void dnode_clear_range(dnode_t *dn, uint64_t blkid, uint64_t nblks, dmu_tx_t *tx) { avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; avl_index_t where; free_range_t *rp; free_range_t rp_tofind; uint64_t endblk = blkid + nblks; ASSERT(MUTEX_HELD(&dn->dn_mtx)); ASSERT(nblks <= UINT64_MAX - blkid); /* no overflow */ dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", blkid, nblks, tx->tx_txg); rp_tofind.fr_blkid = blkid; rp = avl_find(tree, &rp_tofind, &where); if (rp == NULL) rp = avl_nearest(tree, where, AVL_BEFORE); if (rp == NULL) rp = avl_nearest(tree, where, AVL_AFTER); while (rp && (rp->fr_blkid <= blkid + nblks)) { uint64_t fr_endblk = rp->fr_blkid + rp->fr_nblks; free_range_t *nrp = AVL_NEXT(tree, rp); if (blkid <= rp->fr_blkid && endblk >= fr_endblk) { /* clear this entire range */ avl_remove(tree, rp); kmem_free(rp, sizeof (free_range_t)); } else if (blkid <= rp->fr_blkid && endblk > rp->fr_blkid && endblk < fr_endblk) { /* clear the beginning of this range */ rp->fr_blkid = endblk; rp->fr_nblks = fr_endblk - endblk; } else if (blkid > rp->fr_blkid && blkid < fr_endblk && endblk >= fr_endblk) { /* clear the end of this range */ rp->fr_nblks = blkid - rp->fr_blkid; } else if (blkid > rp->fr_blkid && endblk < fr_endblk) { /* clear a chunk out of this range */ free_range_t *new_rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); new_rp->fr_blkid = endblk; new_rp->fr_nblks = fr_endblk - endblk; avl_insert_here(tree, new_rp, rp, AVL_AFTER); rp->fr_nblks = blkid - rp->fr_blkid; } /* there may be no overlap */ rp = nrp; } } void dnode_free_range(dnode_t *dn, uint64_t off, uint64_t len, dmu_tx_t *tx) { dmu_buf_impl_t *db; uint64_t blkoff, blkid, nblks; int blksz, blkshift, head, tail; int trunc = FALSE; int epbs; rw_enter(&dn->dn_struct_rwlock, RW_WRITER); blksz = dn->dn_datablksz; blkshift = dn->dn_datablkshift; epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; if (len == -1ULL) { len = UINT64_MAX - off; trunc = TRUE; } /* * First, block align the region to free: */ if (ISP2(blksz)) { head = P2NPHASE(off, blksz); blkoff = P2PHASE(off, blksz); if ((off >> blkshift) > dn->dn_maxblkid) goto out; } else { ASSERT(dn->dn_maxblkid == 0); if (off == 0 && len >= blksz) { /* Freeing the whole block; fast-track this request */ blkid = 0; nblks = 1; goto done; } else if (off >= blksz) { /* Freeing past end-of-data */ goto out; } else { /* Freeing part of the block. */ head = blksz - off; ASSERT3U(head, >, 0); } blkoff = off; } /* zero out any partial block data at the start of the range */ if (head) { ASSERT3U(blkoff + head, ==, blksz); if (len < head) head = len; if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off), TRUE, FTAG, &db) == 0) { caddr_t data; /* don't dirty if it isn't on disk and isn't dirty */ if (db->db_last_dirty || (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { rw_exit(&dn->dn_struct_rwlock); dbuf_will_dirty(db, tx); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); data = db->db.db_data; bzero(data + blkoff, head); } dbuf_rele(db, FTAG); } off += head; len -= head; } /* If the range was less than one block, we're done */ if (len == 0) goto out; /* If the remaining range is past end of file, we're done */ if ((off >> blkshift) > dn->dn_maxblkid) goto out; ASSERT(ISP2(blksz)); if (trunc) tail = 0; else tail = P2PHASE(len, blksz); ASSERT3U(P2PHASE(off, blksz), ==, 0); /* zero out any partial block data at the end of the range */ if (tail) { if (len < tail) tail = len; if (dbuf_hold_impl(dn, 0, dbuf_whichblock(dn, off+len), TRUE, FTAG, &db) == 0) { /* don't dirty if not on disk and not dirty */ if (db->db_last_dirty || (db->db_blkptr && !BP_IS_HOLE(db->db_blkptr))) { rw_exit(&dn->dn_struct_rwlock); dbuf_will_dirty(db, tx); rw_enter(&dn->dn_struct_rwlock, RW_WRITER); bzero(db->db.db_data, tail); } dbuf_rele(db, FTAG); } len -= tail; } /* If the range did not include a full block, we are done */ if (len == 0) goto out; ASSERT(IS_P2ALIGNED(off, blksz)); ASSERT(trunc || IS_P2ALIGNED(len, blksz)); blkid = off >> blkshift; nblks = len >> blkshift; if (trunc) nblks += 1; /* * Read in and mark all the level-1 indirects dirty, * so that they will stay in memory until syncing phase. * Always dirty the first and last indirect to make sure * we dirty all the partial indirects. */ if (dn->dn_nlevels > 1) { uint64_t i, first, last; int shift = epbs + dn->dn_datablkshift; first = blkid >> epbs; if (db = dbuf_hold_level(dn, 1, first, FTAG)) { dbuf_will_dirty(db, tx); dbuf_rele(db, FTAG); } if (trunc) last = dn->dn_maxblkid >> epbs; else last = (blkid + nblks - 1) >> epbs; if (last > first && (db = dbuf_hold_level(dn, 1, last, FTAG))) { dbuf_will_dirty(db, tx); dbuf_rele(db, FTAG); } for (i = first + 1; i < last; i++) { uint64_t ibyte = i << shift; int err; err = dnode_next_offset(dn, DNODE_FIND_HAVELOCK, &ibyte, 1, 1, 0); i = ibyte >> shift; if (err == ESRCH || i >= last) break; ASSERT(err == 0); db = dbuf_hold_level(dn, 1, i, FTAG); if (db) { dbuf_will_dirty(db, tx); dbuf_rele(db, FTAG); } } } done: /* * Add this range to the dnode range list. * We will finish up this free operation in the syncing phase. */ mutex_enter(&dn->dn_mtx); dnode_clear_range(dn, blkid, nblks, tx); { free_range_t *rp, *found; avl_index_t where; avl_tree_t *tree = &dn->dn_ranges[tx->tx_txg&TXG_MASK]; /* Add new range to dn_ranges */ rp = kmem_alloc(sizeof (free_range_t), KM_SLEEP); rp->fr_blkid = blkid; rp->fr_nblks = nblks; found = avl_find(tree, rp, &where); ASSERT(found == NULL); avl_insert(tree, rp, where); dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n", blkid, nblks, tx->tx_txg); } mutex_exit(&dn->dn_mtx); dbuf_free_range(dn, blkid, blkid + nblks - 1, tx); dnode_setdirty(dn, tx); out: if (trunc && dn->dn_maxblkid >= (off >> blkshift)) dn->dn_maxblkid = (off >> blkshift ? (off >> blkshift) - 1 : 0); rw_exit(&dn->dn_struct_rwlock); } static boolean_t dnode_spill_freed(dnode_t *dn) { int i; mutex_enter(&dn->dn_mtx); for (i = 0; i < TXG_SIZE; i++) { if (dn->dn_rm_spillblk[i] == DN_KILL_SPILLBLK) break; } mutex_exit(&dn->dn_mtx); return (i < TXG_SIZE); } /* return TRUE if this blkid was freed in a recent txg, or FALSE if it wasn't */ uint64_t dnode_block_freed(dnode_t *dn, uint64_t blkid) { free_range_t range_tofind; void *dp = spa_get_dsl(dn->dn_objset->os_spa); int i; if (blkid == DMU_BONUS_BLKID) return (FALSE); /* * If we're in the process of opening the pool, dp will not be * set yet, but there shouldn't be anything dirty. */ if (dp == NULL) return (FALSE); if (dn->dn_free_txg) return (TRUE); if (blkid == DMU_SPILL_BLKID) return (dnode_spill_freed(dn)); range_tofind.fr_blkid = blkid; mutex_enter(&dn->dn_mtx); for (i = 0; i < TXG_SIZE; i++) { free_range_t *range_found; avl_index_t idx; range_found = avl_find(&dn->dn_ranges[i], &range_tofind, &idx); if (range_found) { ASSERT(range_found->fr_nblks > 0); break; } range_found = avl_nearest(&dn->dn_ranges[i], idx, AVL_BEFORE); if (range_found && range_found->fr_blkid + range_found->fr_nblks > blkid) break; } mutex_exit(&dn->dn_mtx); return (i < TXG_SIZE); } /* call from syncing context when we actually write/free space for this dnode */ void dnode_diduse_space(dnode_t *dn, int64_t delta) { uint64_t space; dprintf_dnode(dn, "dn=%p dnp=%p used=%llu delta=%lld\n", dn, dn->dn_phys, (u_longlong_t)dn->dn_phys->dn_used, (longlong_t)delta); mutex_enter(&dn->dn_mtx); space = DN_USED_BYTES(dn->dn_phys); if (delta > 0) { ASSERT3U(space + delta, >=, space); /* no overflow */ } else { ASSERT3U(space, >=, -delta); /* no underflow */ } space += delta; if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_DNODE_BYTES) { ASSERT((dn->dn_phys->dn_flags & DNODE_FLAG_USED_BYTES) == 0); ASSERT3U(P2PHASE(space, 1<dn_phys->dn_used = space >> DEV_BSHIFT; } else { dn->dn_phys->dn_used = space; dn->dn_phys->dn_flags |= DNODE_FLAG_USED_BYTES; } mutex_exit(&dn->dn_mtx); } /* * Call when we think we're going to write/free space in open context. * Be conservative (ie. OK to write less than this or free more than * this, but don't write more or free less). */ void dnode_willuse_space(dnode_t *dn, int64_t space, dmu_tx_t *tx) { objset_t *os = dn->dn_objset; dsl_dataset_t *ds = os->os_dsl_dataset; if (space > 0) space = spa_get_asize(os->os_spa, space); if (ds) dsl_dir_willuse_space(ds->ds_dir, space, tx); dmu_tx_willuse_space(tx, space); } /* * This function scans a block at the indicated "level" looking for * a hole or data (depending on 'flags'). If level > 0, then we are * scanning an indirect block looking at its pointers. If level == 0, * then we are looking at a block of dnodes. If we don't find what we * are looking for in the block, we return ESRCH. Otherwise, return * with *offset pointing to the beginning (if searching forwards) or * end (if searching backwards) of the range covered by the block * pointer we matched on (or dnode). * * The basic search algorithm used below by dnode_next_offset() is to * use this function to search up the block tree (widen the search) until * we find something (i.e., we don't return ESRCH) and then search back * down the tree (narrow the search) until we reach our original search * level. */ static int dnode_next_offset_level(dnode_t *dn, int flags, uint64_t *offset, int lvl, uint64_t blkfill, uint64_t txg) { dmu_buf_impl_t *db = NULL; void *data = NULL; uint64_t epbs = dn->dn_phys->dn_indblkshift - SPA_BLKPTRSHIFT; uint64_t epb = 1ULL << epbs; uint64_t minfill, maxfill; boolean_t hole; int i, inc, error, span; dprintf("probing object %llu offset %llx level %d of %u\n", dn->dn_object, *offset, lvl, dn->dn_phys->dn_nlevels); hole = ((flags & DNODE_FIND_HOLE) != 0); inc = (flags & DNODE_FIND_BACKWARDS) ? -1 : 1; ASSERT(txg == 0 || !hole); if (lvl == dn->dn_phys->dn_nlevels) { error = 0; epb = dn->dn_phys->dn_nblkptr; data = dn->dn_phys->dn_blkptr; } else { uint64_t blkid = dbuf_whichblock(dn, *offset) >> (epbs * lvl); error = dbuf_hold_impl(dn, lvl, blkid, TRUE, FTAG, &db); if (error) { if (error != ENOENT) return (error); if (hole) return (0); /* * This can only happen when we are searching up * the block tree for data. We don't really need to * adjust the offset, as we will just end up looking * at the pointer to this block in its parent, and its * going to be unallocated, so we will skip over it. */ return (ESRCH); } error = dbuf_read(db, NULL, DB_RF_CANFAIL | DB_RF_HAVESTRUCT); if (error) { dbuf_rele(db, FTAG); return (error); } data = db->db.db_data; } if (db && txg && (db->db_blkptr == NULL || db->db_blkptr->blk_birth <= txg)) { /* * This can only happen when we are searching up the tree * and these conditions mean that we need to keep climbing. */ error = ESRCH; } else if (lvl == 0) { dnode_phys_t *dnp = data; span = DNODE_SHIFT; ASSERT(dn->dn_type == DMU_OT_DNODE); for (i = (*offset >> span) & (blkfill - 1); i >= 0 && i < blkfill; i += inc) { if ((dnp[i].dn_type == DMU_OT_NONE) == hole) break; *offset += (1ULL << span) * inc; } if (i < 0 || i == blkfill) error = ESRCH; } else { blkptr_t *bp = data; uint64_t start = *offset; span = (lvl - 1) * epbs + dn->dn_datablkshift; minfill = 0; maxfill = blkfill << ((lvl - 1) * epbs); if (hole) maxfill--; else minfill++; *offset = *offset >> span; for (i = BF64_GET(*offset, 0, epbs); i >= 0 && i < epb; i += inc) { if (bp[i].blk_fill >= minfill && bp[i].blk_fill <= maxfill && (hole || bp[i].blk_birth > txg)) break; if (inc > 0 || *offset > 0) *offset += inc; } *offset = *offset << span; if (inc < 0) { /* traversing backwards; position offset at the end */ ASSERT3U(*offset, <=, start); *offset = MIN(*offset + (1ULL << span) - 1, start); } else if (*offset < start) { *offset = start; } if (i < 0 || i >= epb) error = ESRCH; } if (db) dbuf_rele(db, FTAG); return (error); } /* * Find the next hole, data, or sparse region at or after *offset. * The value 'blkfill' tells us how many items we expect to find * in an L0 data block; this value is 1 for normal objects, * DNODES_PER_BLOCK for the meta dnode, and some fraction of * DNODES_PER_BLOCK when searching for sparse regions thereof. * * Examples: * * dnode_next_offset(dn, flags, offset, 1, 1, 0); * Finds the next/previous hole/data in a file. * Used in dmu_offset_next(). * * dnode_next_offset(mdn, flags, offset, 0, DNODES_PER_BLOCK, txg); * Finds the next free/allocated dnode an objset's meta-dnode. * Only finds objects that have new contents since txg (ie. * bonus buffer changes and content removal are ignored). * Used in dmu_object_next(). * * dnode_next_offset(mdn, DNODE_FIND_HOLE, offset, 2, DNODES_PER_BLOCK >> 2, 0); * Finds the next L2 meta-dnode bp that's at most 1/4 full. * Used in dmu_object_alloc(). */ int dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset, int minlvl, uint64_t blkfill, uint64_t txg) { uint64_t initial_offset = *offset; int lvl, maxlvl; int error = 0; if (!(flags & DNODE_FIND_HAVELOCK)) rw_enter(&dn->dn_struct_rwlock, RW_READER); if (dn->dn_phys->dn_nlevels == 0) { error = ESRCH; goto out; } if (dn->dn_datablkshift == 0) { if (*offset < dn->dn_datablksz) { if (flags & DNODE_FIND_HOLE) *offset = dn->dn_datablksz; } else { error = ESRCH; } goto out; } maxlvl = dn->dn_phys->dn_nlevels; for (lvl = minlvl; lvl <= maxlvl; lvl++) { error = dnode_next_offset_level(dn, flags, offset, lvl, blkfill, txg); if (error != ESRCH) break; } while (error == 0 && --lvl >= minlvl) { error = dnode_next_offset_level(dn, flags, offset, lvl, blkfill, txg); } if (error == 0 && (flags & DNODE_FIND_BACKWARDS ? initial_offset < *offset : initial_offset > *offset)) error = ESRCH; out: if (!(flags & DNODE_FIND_HAVELOCK)) rw_exit(&dn->dn_struct_rwlock); return (error); }