1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_DMU_IMPL_H 27 #define _SYS_DMU_IMPL_H 28 29 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 #include <sys/txg_impl.h> 32 #include <sys/zio.h> 33 #include <sys/dnode.h> 34 #include <sys/zfs_context.h> 35 36 #ifdef __cplusplus 37 extern "C" { 38 #endif 39 40 /* 41 * This is the locking strategy for the DMU. Numbers in parenthesis are 42 * cases that use that lock order, referenced below: 43 * 44 * ARC is self-contained 45 * bplist is self-contained 46 * refcount is self-contained 47 * txg is self-contained (hopefully!) 48 * zst_lock 49 * zf_rwlock 50 * 51 * XXX try to improve evicting path? 52 * 53 * dp_config_rwlock > os_obj_lock > dn_struct_rwlock > 54 * dn_dbufs_mtx > hash_mutexes > db_mtx > leafs 55 * 56 * dp_config_rwlock 57 * must be held before: everything 58 * protects dd namespace changes 59 * protects property changes globally 60 * held from: 61 * dsl_dir_open/r: 62 * dsl_dir_create_sync/w: 63 * dsl_dir_sync_destroy/w: 64 * dsl_dir_rename_sync/w: 65 * dsl_prop_changed_notify/r: 66 * 67 * os_obj_lock 68 * must be held before: 69 * everything except dp_config_rwlock 70 * protects os_obj_next 71 * held from: 72 * dmu_object_alloc: dn_dbufs_mtx, db_mtx, hash_mutexes, dn_struct_rwlock 73 * 74 * dn_struct_rwlock 75 * must be held before: 76 * everything except dp_config_rwlock and os_obj_lock 77 * protects structure of dnode (eg. nlevels) 78 * db_blkptr can change when syncing out change to nlevels 79 * dn_maxblkid 80 * dn_nlevels 81 * dn_*blksz* 82 * phys nlevels, maxblkid, physical blkptr_t's (?) 83 * held from: 84 * callers of dbuf_read_impl, dbuf_hold[_impl], dbuf_prefetch 85 * dmu_object_info_from_dnode: dn_dirty_mtx (dn_datablksz) 86 * dmu_tx_count_free: 87 * dbuf_read_impl: db_mtx, dmu_zfetch() 88 * dmu_zfetch: zf_rwlock/r, zst_lock, dbuf_prefetch() 89 * dbuf_new_size: db_mtx 90 * dbuf_dirty: db_mtx 91 * dbuf_findbp: (callers, phys? - the real need) 92 * dbuf_create: dn_dbufs_mtx, hash_mutexes, db_mtx (phys?) 93 * dbuf_prefetch: dn_dirty_mtx, hash_mutexes, db_mtx, dn_dbufs_mtx 94 * dbuf_hold_impl: hash_mutexes, db_mtx, dn_dbufs_mtx, dbuf_findbp() 95 * dnode_sync/w (increase_indirection): db_mtx (phys) 96 * dnode_set_blksz/w: dn_dbufs_mtx (dn_*blksz*) 97 * dnode_new_blkid/w: (dn_maxblkid) 98 * dnode_free_range/w: dn_dirty_mtx (dn_maxblkid) 99 * dnode_next_offset: (phys) 100 * 101 * dn_dbufs_mtx 102 * must be held before: 103 * db_mtx, hash_mutexes 104 * protects: 105 * dn_dbufs 106 * dn_evicted 107 * held from: 108 * dmu_evict_user: db_mtx (dn_dbufs) 109 * dbuf_free_range: db_mtx (dn_dbufs) 110 * dbuf_remove_ref: db_mtx, callees: 111 * dbuf_hash_remove: hash_mutexes, db_mtx 112 * dbuf_create: hash_mutexes, db_mtx (dn_dbufs) 113 * dnode_set_blksz: (dn_dbufs) 114 * 115 * hash_mutexes (global) 116 * must be held before: 117 * db_mtx 118 * protects dbuf_hash_table (global) and db_hash_next 119 * held from: 120 * dbuf_find: db_mtx 121 * dbuf_hash_insert: db_mtx 122 * dbuf_hash_remove: db_mtx 123 * 124 * db_mtx (meta-leaf) 125 * must be held before: 126 * dn_mtx, dn_dirty_mtx, dd_lock (leaf mutexes) 127 * protects: 128 * db_state 129 * db_holds 130 * db_buf 131 * db_changed 132 * db_data_pending 133 * db_dirtied 134 * db_link 135 * db_dirty_node (??) 136 * db_dirtycnt 137 * db_d.* 138 * db.* 139 * held from: 140 * dbuf_dirty: dn_mtx, dn_dirty_mtx 141 * dbuf_dirty->dsl_dir_willuse_space: dd_lock 142 * dbuf_dirty->dbuf_new_block->dsl_dataset_block_freeable: dd_lock 143 * dbuf_undirty: dn_dirty_mtx (db_d) 144 * dbuf_write_done: dn_dirty_mtx (db_state) 145 * dbuf_* 146 * dmu_buf_update_user: none (db_d) 147 * dmu_evict_user: none (db_d) (maybe can eliminate) 148 * dbuf_find: none (db_holds) 149 * dbuf_hash_insert: none (db_holds) 150 * dmu_buf_read_array_impl: none (db_state, db_changed) 151 * dmu_sync: none (db_dirty_node, db_d) 152 * dnode_reallocate: none (db) 153 * 154 * dn_mtx (leaf) 155 * protects: 156 * dn_dirty_dbufs 157 * dn_ranges 158 * phys accounting 159 * dn_allocated_txg 160 * dn_free_txg 161 * dn_assigned_txg 162 * dd_assigned_tx 163 * dn_notxholds 164 * dn_dirtyctx 165 * dn_dirtyctx_firstset 166 * (dn_phys copy fields?) 167 * (dn_phys contents?) 168 * held from: 169 * dnode_* 170 * dbuf_dirty: none 171 * dbuf_sync: none (phys accounting) 172 * dbuf_undirty: none (dn_ranges, dn_dirty_dbufs) 173 * dbuf_write_done: none (phys accounting) 174 * dmu_object_info_from_dnode: none (accounting) 175 * dmu_tx_commit: none 176 * dmu_tx_hold_object_impl: none 177 * dmu_tx_try_assign: dn_notxholds(cv) 178 * dmu_tx_unassign: none 179 * 180 * dd_lock (leaf) 181 * protects: 182 * dd_prop_cbs 183 * dd_sync_* 184 * dd_used_bytes 185 * dd_tempreserved 186 * dd_space_towrite 187 * dd_myname 188 * dd_phys accounting? 189 * held from: 190 * dsl_dir_* 191 * dsl_prop_changed_notify: none (dd_prop_cbs) 192 * dsl_prop_register: none (dd_prop_cbs) 193 * dsl_prop_unregister: none (dd_prop_cbs) 194 * dsl_dataset_block_freeable: none (dd_sync_*) 195 * 196 * os_lock (leaf) 197 * protects: 198 * os_dirty_dnodes 199 * os_free_dnodes 200 * os_dnodes 201 * os_downgraded_dbufs 202 * dn_dirtyblksz 203 * dn_dirty_link 204 * held from: 205 * dnode_create: none (os_dnodes) 206 * dnode_destroy: none (os_dnodes) 207 * dnode_setdirty: none (dn_dirtyblksz, os_*_dnodes) 208 * dnode_free: none (dn_dirtyblksz, os_*_dnodes) 209 * 210 * ds_lock (leaf) 211 * protects: 212 * ds_user_ptr 213 * ds_user_evice_func 214 * ds_open_refcount 215 * ds_snapname 216 * ds_phys accounting 217 * held from: 218 * dsl_dataset_* 219 * 220 * dr_mtx (leaf) 221 * protects: 222 * dr_children 223 * held from: 224 * dbuf_dirty 225 * dbuf_undirty 226 * dbuf_sync_indirect 227 * dnode_new_blkid 228 */ 229 230 struct objset; 231 struct dmu_pool; 232 233 #ifdef __cplusplus 234 } 235 #endif 236 237 #endif /* _SYS_DMU_IMPL_H */ 238