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 https://opensource.org/licenses/CDDL-1.0.
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 2010 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25/*
26 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
27 * Copyright (c) 2013, 2018 by Delphix. All rights reserved.
28 */
29
30#ifndef _SYS_DMU_IMPL_H
31#define	_SYS_DMU_IMPL_H
32
33#include <sys/txg_impl.h>
34#include <sys/zio.h>
35#include <sys/dnode.h>
36#include <sys/zfs_context.h>
37#include <sys/zfs_ioctl.h>
38
39#ifdef	__cplusplus
40extern "C" {
41#endif
42
43/*
44 * This is the locking strategy for the DMU.  Numbers in parenthesis are
45 * cases that use that lock order, referenced below:
46 *
47 * ARC is self-contained
48 * bplist is self-contained
49 * refcount is self-contained
50 * txg is self-contained (hopefully!)
51 * zst_lock
52 * zf_rwlock
53 *
54 * XXX try to improve evicting path?
55 *
56 * dp_config_rwlock > os_obj_lock > dn_struct_rwlock >
57 * 	dn_dbufs_mtx > hash_mutexes > db_mtx > dd_lock > leafs
58 *
59 * dp_config_rwlock
60 *    must be held before: everything
61 *    protects dd namespace changes
62 *    protects property changes globally
63 *    held from:
64 *    	dsl_dir_open/r:
65 *    	dsl_dir_create_sync/w:
66 *    	dsl_dir_sync_destroy/w:
67 *    	dsl_dir_rename_sync/w:
68 *    	dsl_prop_changed_notify/r:
69 *
70 * os_obj_lock
71 *   must be held before:
72 *   	everything except dp_config_rwlock
73 *   protects os_obj_next
74 *   held from:
75 *   	dmu_object_alloc: dn_dbufs_mtx, db_mtx, hash_mutexes, dn_struct_rwlock
76 *
77 * dn_struct_rwlock
78 *   must be held before:
79 *   	everything except dp_config_rwlock and os_obj_lock
80 *   protects structure of dnode (eg. nlevels)
81 *   	db_blkptr can change when syncing out change to nlevels
82 *   	dn_maxblkid
83 *   	dn_nlevels
84 *   	dn_*blksz*
85 *   	phys nlevels, maxblkid, physical blkptr_t's (?)
86 *   held from:
87 *   	callers of dbuf_read_impl, dbuf_hold[_impl], dbuf_prefetch
88 *   	dmu_object_info_from_dnode: dn_dirty_mtx (dn_datablksz)
89 *   	dbuf_read_impl: db_mtx, dmu_zfetch()
90 *   	dmu_zfetch: zf_rwlock/r, zst_lock, dbuf_prefetch()
91 *   	dbuf_new_size: db_mtx
92 *   	dbuf_dirty: db_mtx
93 *	dbuf_findbp: (callers, phys? - the real need)
94 *	dbuf_create: dn_dbufs_mtx, hash_mutexes, db_mtx (phys?)
95 *	dbuf_prefetch: dn_dirty_mtx, hash_mutexes, db_mtx, dn_dbufs_mtx
96 *	dbuf_hold_impl: hash_mutexes, db_mtx, dn_dbufs_mtx, dbuf_findbp()
97 *	dnode_sync/w (increase_indirection): db_mtx (phys)
98 *	dnode_set_blksz/w: dn_dbufs_mtx (dn_*blksz*)
99 *	dnode_new_blkid/w: (dn_maxblkid)
100 *	dnode_free_range/w: dn_dirty_mtx (dn_maxblkid)
101 *	dnode_next_offset: (phys)
102 *
103 * dn_dbufs_mtx
104 *    must be held before:
105 *    	db_mtx, hash_mutexes
106 *    protects:
107 *    	dn_dbufs
108 *    	dn_evicted
109 *    held from:
110 *    	dmu_evict_user: db_mtx (dn_dbufs)
111 *    	dbuf_free_range: db_mtx (dn_dbufs)
112 *    	dbuf_remove_ref: db_mtx, callees:
113 *    		dbuf_hash_remove: hash_mutexes, db_mtx
114 *    	dbuf_create: hash_mutexes, db_mtx (dn_dbufs)
115 *    	dnode_set_blksz: (dn_dbufs)
116 *
117 * hash_mutexes (global)
118 *   must be held before:
119 *   	db_mtx
120 *   protects dbuf_hash_table (global) and db_hash_next
121 *   held from:
122 *   	dbuf_find: db_mtx
123 *   	dbuf_hash_insert: db_mtx
124 *   	dbuf_hash_remove: db_mtx
125 *
126 * db_mtx (meta-leaf)
127 *   must be held before:
128 *   	dn_mtx, dn_dirty_mtx, dd_lock (leaf mutexes)
129 *   protects:
130 *   	db_state
131 * 	db_holds
132 * 	db_buf
133 * 	db_changed
134 * 	db_data_pending
135 * 	db_dirtied
136 * 	db_link
137 * 	db_dirty_node (??)
138 * 	db_dirtycnt
139 * 	db_d.*
140 * 	db.*
141 *   held from:
142 * 	dbuf_dirty: dn_mtx, dn_dirty_mtx
143 * 	dbuf_dirty->dsl_dir_willuse_space: dd_lock
144 * 	dbuf_dirty->dbuf_new_block->dsl_dataset_block_freeable: dd_lock
145 * 	dbuf_undirty: dn_dirty_mtx (db_d)
146 * 	dbuf_write_done: dn_dirty_mtx (db_state)
147 * 	dbuf_*
148 * 	dmu_buf_update_user: none (db_d)
149 * 	dmu_evict_user: none (db_d) (maybe can eliminate)
150 *   	dbuf_find: none (db_holds)
151 *   	dbuf_hash_insert: none (db_holds)
152 *   	dmu_buf_read_array_impl: none (db_state, db_changed)
153 *   	dmu_sync: none (db_dirty_node, db_d)
154 *   	dnode_reallocate: none (db)
155 *
156 * dn_mtx (leaf)
157 *   protects:
158 *   	dn_dirty_dbufs
159 *   	dn_ranges
160 *   	phys accounting
161 * 	dn_allocated_txg
162 * 	dn_free_txg
163 * 	dn_assigned_txg
164 * 	dn_dirty_txg
165 * 	dd_assigned_tx
166 * 	dn_notxholds
167 *	dn_nodnholds
168 * 	dn_dirtyctx
169 * 	dn_dirtyctx_firstset
170 * 	(dn_phys copy fields?)
171 * 	(dn_phys contents?)
172 *   held from:
173 *   	dnode_*
174 *   	dbuf_dirty: none
175 *   	dbuf_sync: none (phys accounting)
176 *   	dbuf_undirty: none (dn_ranges, dn_dirty_dbufs)
177 *   	dbuf_write_done: none (phys accounting)
178 *   	dmu_object_info_from_dnode: none (accounting)
179 *   	dmu_tx_commit: none
180 *   	dmu_tx_hold_object_impl: none
181 *   	dmu_tx_try_assign: dn_notxholds(cv)
182 *   	dmu_tx_unassign: none
183 *
184 * dd_lock
185 *    must be held before:
186 *      ds_lock
187 *      ancestors' dd_lock
188 *    protects:
189 *    	dd_prop_cbs
190 *    	dd_sync_*
191 *    	dd_used_bytes
192 *    	dd_tempreserved
193 *    	dd_space_towrite
194 *    	dd_myname
195 *    	dd_phys accounting?
196 *    held from:
197 *    	dsl_dir_*
198 *    	dsl_prop_changed_notify: none (dd_prop_cbs)
199 *    	dsl_prop_register: none (dd_prop_cbs)
200 *    	dsl_prop_unregister: none (dd_prop_cbs)
201 *
202 * os_lock (leaf)
203 *   protects:
204 *   	os_dirty_dnodes
205 *   	os_free_dnodes
206 *   	os_dnodes
207 *   	os_downgraded_dbufs
208 *   	dn_dirtyblksz
209 *   	dn_dirty_link
210 *   held from:
211 *   	dnode_create: none (os_dnodes)
212 *   	dnode_destroy: none (os_dnodes)
213 *   	dnode_setdirty: none (dn_dirtyblksz, os_*_dnodes)
214 *   	dnode_free: none (dn_dirtyblksz, os_*_dnodes)
215 *
216 * ds_lock
217 *    protects:
218 *    	ds_objset
219 *    	ds_open_refcount
220 *    	ds_snapname
221 *    	ds_phys accounting
222 *	ds_phys userrefs zapobj
223 *	ds_reserved
224 *    held from:
225 *    	dsl_dataset_*
226 *
227 * dr_mtx (leaf)
228 *    protects:
229 *	dr_children
230 *    held from:
231 *	dbuf_dirty
232 *	dbuf_undirty
233 *	dbuf_sync_indirect
234 *	dnode_new_blkid
235 */
236
237struct objset;
238struct dmu_pool;
239
240typedef struct dmu_sendstatus {
241	list_node_t dss_link;
242	int dss_outfd;
243	proc_t *dss_proc;
244	offset_t *dss_off;
245	uint64_t dss_blocks; /* blocks visited during the sending process */
246} dmu_sendstatus_t;
247
248void dmu_object_zapify(objset_t *, uint64_t, dmu_object_type_t, dmu_tx_t *);
249void dmu_object_free_zapified(objset_t *, uint64_t, dmu_tx_t *);
250
251#ifdef	__cplusplus
252}
253#endif
254
255#endif	/* _SYS_DMU_IMPL_H */
256