xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/dsl_dataset.h (revision e77c795bcbe51aebd7579fe13cbf2a6d56eca47f)
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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 
25 #ifndef	_SYS_DSL_DATASET_H
26 #define	_SYS_DSL_DATASET_H
27 
28 #include <sys/dmu.h>
29 #include <sys/spa.h>
30 #include <sys/txg.h>
31 #include <sys/zio.h>
32 #include <sys/bplist.h>
33 #include <sys/dsl_synctask.h>
34 #include <sys/zfs_context.h>
35 #include <sys/dsl_deadlist.h>
36 
37 #ifdef	__cplusplus
38 extern "C" {
39 #endif
40 
41 struct dsl_dataset;
42 struct dsl_dir;
43 struct dsl_pool;
44 
45 #define	DS_FLAG_INCONSISTENT	(1ULL<<0)
46 #define	DS_IS_INCONSISTENT(ds)	\
47 	((ds)->ds_phys->ds_flags & DS_FLAG_INCONSISTENT)
48 /*
49  * NB: nopromote can not yet be set, but we want support for it in this
50  * on-disk version, so that we don't need to upgrade for it later.  It
51  * will be needed when we implement 'zfs split' (where the split off
52  * clone should not be promoted).
53  */
54 #define	DS_FLAG_NOPROMOTE	(1ULL<<1)
55 
56 /*
57  * DS_FLAG_UNIQUE_ACCURATE is set if ds_unique_bytes has been correctly
58  * calculated for head datasets (starting with SPA_VERSION_UNIQUE_ACCURATE,
59  * refquota/refreservations).
60  */
61 #define	DS_FLAG_UNIQUE_ACCURATE	(1ULL<<2)
62 
63 /*
64  * DS_FLAG_DEFER_DESTROY is set after 'zfs destroy -d' has been called
65  * on a dataset. This allows the dataset to be destroyed using 'zfs release'.
66  */
67 #define	DS_FLAG_DEFER_DESTROY	(1ULL<<3)
68 #define	DS_IS_DEFER_DESTROY(ds)	\
69 	((ds)->ds_phys->ds_flags & DS_FLAG_DEFER_DESTROY)
70 
71 /*
72  * DS_FLAG_CI_DATASET is set if the dataset contains a file system whose
73  * name lookups should be performed case-insensitively.
74  */
75 #define	DS_FLAG_CI_DATASET	(1ULL<<16)
76 
77 typedef struct dsl_dataset_phys {
78 	uint64_t ds_dir_obj;		/* DMU_OT_DSL_DIR */
79 	uint64_t ds_prev_snap_obj;	/* DMU_OT_DSL_DATASET */
80 	uint64_t ds_prev_snap_txg;
81 	uint64_t ds_next_snap_obj;	/* DMU_OT_DSL_DATASET */
82 	uint64_t ds_snapnames_zapobj;	/* DMU_OT_DSL_DS_SNAP_MAP 0 for snaps */
83 	uint64_t ds_num_children;	/* clone/snap children; ==0 for head */
84 	uint64_t ds_creation_time;	/* seconds since 1970 */
85 	uint64_t ds_creation_txg;
86 	uint64_t ds_deadlist_obj;	/* DMU_OT_DEADLIST */
87 	uint64_t ds_used_bytes;
88 	uint64_t ds_compressed_bytes;
89 	uint64_t ds_uncompressed_bytes;
90 	uint64_t ds_unique_bytes;	/* only relevant to snapshots */
91 	/*
92 	 * The ds_fsid_guid is a 56-bit ID that can change to avoid
93 	 * collisions.  The ds_guid is a 64-bit ID that will never
94 	 * change, so there is a small probability that it will collide.
95 	 */
96 	uint64_t ds_fsid_guid;
97 	uint64_t ds_guid;
98 	uint64_t ds_flags;		/* DS_FLAG_* */
99 	blkptr_t ds_bp;
100 	uint64_t ds_next_clones_obj;	/* DMU_OT_DSL_CLONES */
101 	uint64_t ds_props_obj;		/* DMU_OT_DSL_PROPS for snaps */
102 	uint64_t ds_userrefs_obj;	/* DMU_OT_USERREFS */
103 	uint64_t ds_pad[5]; /* pad out to 320 bytes for good measure */
104 } dsl_dataset_phys_t;
105 
106 typedef struct dsl_dataset {
107 	/* Immutable: */
108 	struct dsl_dir *ds_dir;
109 	dsl_dataset_phys_t *ds_phys;
110 	dmu_buf_t *ds_dbuf;
111 	uint64_t ds_object;
112 	uint64_t ds_fsid_guid;
113 
114 	/* only used in syncing context, only valid for non-snapshots: */
115 	struct dsl_dataset *ds_prev;
116 
117 	/* has internal locking: */
118 	dsl_deadlist_t ds_deadlist;
119 	bplist_t ds_pending_deadlist;
120 
121 	/* to protect against multiple concurrent incremental recv */
122 	kmutex_t ds_recvlock;
123 
124 	/* protected by lock on pool's dp_dirty_datasets list */
125 	txg_node_t ds_dirty_link;
126 	list_node_t ds_synced_link;
127 
128 	/*
129 	 * ds_phys->ds_<accounting> is also protected by ds_lock.
130 	 * Protected by ds_lock:
131 	 */
132 	kmutex_t ds_lock;
133 	objset_t *ds_objset;
134 	uint64_t ds_userrefs;
135 
136 	/*
137 	 * ds_owner is protected by the ds_rwlock and the ds_lock
138 	 */
139 	krwlock_t ds_rwlock;
140 	kcondvar_t ds_exclusive_cv;
141 	void *ds_owner;
142 
143 	/* no locking; only for making guesses */
144 	uint64_t ds_trysnap_txg;
145 
146 	/* for objset_open() */
147 	kmutex_t ds_opening_lock;
148 
149 	uint64_t ds_reserved;	/* cached refreservation */
150 	uint64_t ds_quota;	/* cached refquota */
151 
152 	/* Protected by ds_lock; keep at end of struct for better locality */
153 	char ds_snapname[MAXNAMELEN];
154 } dsl_dataset_t;
155 
156 struct dsl_ds_destroyarg {
157 	dsl_dataset_t *ds;		/* ds to destroy */
158 	dsl_dataset_t *rm_origin;	/* also remove our origin? */
159 	boolean_t is_origin_rm;		/* set if removing origin snap */
160 	boolean_t defer;		/* destroy -d requested? */
161 	boolean_t releasing;		/* destroying due to release? */
162 	boolean_t need_prep;		/* do we need to retry due to EBUSY? */
163 };
164 
165 /*
166  * The max length of a temporary tag prefix is the number of hex digits
167  * required to express UINT64_MAX plus one for the hyphen.
168  */
169 #define	MAX_TAG_PREFIX_LEN	17
170 
171 struct dsl_ds_holdarg {
172 	dsl_sync_task_group_t *dstg;
173 	char *htag;
174 	char *snapname;
175 	boolean_t recursive;
176 	boolean_t gotone;
177 	boolean_t temphold;
178 	char failed[MAXPATHLEN];
179 };
180 
181 #define	dsl_dataset_is_snapshot(ds) \
182 	((ds)->ds_phys->ds_num_children != 0)
183 
184 #define	DS_UNIQUE_IS_ACCURATE(ds)	\
185 	(((ds)->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) != 0)
186 
187 int dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp);
188 int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj,
189     void *tag, dsl_dataset_t **);
190 int dsl_dataset_own(const char *name, boolean_t inconsistentok,
191     void *tag, dsl_dataset_t **dsp);
192 int dsl_dataset_own_obj(struct dsl_pool *dp, uint64_t dsobj,
193     boolean_t inconsistentok, void *tag, dsl_dataset_t **dsp);
194 void dsl_dataset_name(dsl_dataset_t *ds, char *name);
195 void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
196 void dsl_dataset_disown(dsl_dataset_t *ds, void *tag);
197 void dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag);
198 boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok,
199     void *tag);
200 void dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *tag);
201 void dsl_register_onexit_hold_cleanup(dsl_dataset_t *ds, const char *htag,
202     minor_t minor);
203 uint64_t dsl_dataset_create_sync(dsl_dir_t *pds, const char *lastname,
204     dsl_dataset_t *origin, uint64_t flags, cred_t *, dmu_tx_t *);
205 uint64_t dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
206     uint64_t flags, dmu_tx_t *tx);
207 int dsl_dataset_destroy(dsl_dataset_t *ds, void *tag, boolean_t defer);
208 int dsl_snapshots_destroy(char *fsname, char *snapname, boolean_t defer);
209 dsl_checkfunc_t dsl_dataset_destroy_check;
210 dsl_syncfunc_t dsl_dataset_destroy_sync;
211 dsl_checkfunc_t dsl_dataset_snapshot_check;
212 dsl_syncfunc_t dsl_dataset_snapshot_sync;
213 dsl_syncfunc_t dsl_dataset_user_hold_sync;
214 int dsl_dataset_rename(char *name, const char *newname, boolean_t recursive);
215 int dsl_dataset_promote(const char *name, char *conflsnap);
216 int dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head,
217     boolean_t force);
218 int dsl_dataset_user_hold(char *dsname, char *snapname, char *htag,
219     boolean_t recursive, boolean_t temphold, int cleanup_fd);
220 int dsl_dataset_user_hold_for_send(dsl_dataset_t *ds, char *htag,
221     boolean_t temphold);
222 int dsl_dataset_user_release(char *dsname, char *snapname, char *htag,
223     boolean_t recursive);
224 int dsl_dataset_user_release_tmp(struct dsl_pool *dp, uint64_t dsobj,
225     char *htag, boolean_t retry);
226 int dsl_dataset_get_holds(const char *dsname, nvlist_t **nvp);
227 
228 blkptr_t *dsl_dataset_get_blkptr(dsl_dataset_t *ds);
229 void dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx);
230 
231 spa_t *dsl_dataset_get_spa(dsl_dataset_t *ds);
232 
233 boolean_t dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds);
234 
235 void dsl_dataset_sync(dsl_dataset_t *os, zio_t *zio, dmu_tx_t *tx);
236 
237 void dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp,
238     dmu_tx_t *tx);
239 int dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp,
240     dmu_tx_t *tx, boolean_t async);
241 boolean_t dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
242     uint64_t blk_birth);
243 uint64_t dsl_dataset_prev_snap_txg(dsl_dataset_t *ds);
244 
245 void dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx);
246 void dsl_dataset_stats(dsl_dataset_t *os, nvlist_t *nv);
247 void dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat);
248 void dsl_dataset_space(dsl_dataset_t *ds,
249     uint64_t *refdbytesp, uint64_t *availbytesp,
250     uint64_t *usedobjsp, uint64_t *availobjsp);
251 uint64_t dsl_dataset_fsid_guid(dsl_dataset_t *ds);
252 
253 int dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf);
254 
255 int dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
256     uint64_t asize, uint64_t inflight, uint64_t *used,
257     uint64_t *ref_rsrv);
258 int dsl_dataset_set_quota(const char *dsname, zprop_source_t source,
259     uint64_t quota);
260 dsl_syncfunc_t dsl_dataset_set_quota_sync;
261 int dsl_dataset_set_reservation(const char *dsname, zprop_source_t source,
262     uint64_t reservation);
263 
264 int dsl_destroy_inconsistent(const char *dsname, void *arg);
265 
266 #ifdef ZFS_DEBUG
267 #define	dprintf_ds(ds, fmt, ...) do { \
268 	if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
269 	char *__ds_name = kmem_alloc(MAXNAMELEN, KM_SLEEP); \
270 	dsl_dataset_name(ds, __ds_name); \
271 	dprintf("ds=%s " fmt, __ds_name, __VA_ARGS__); \
272 	kmem_free(__ds_name, MAXNAMELEN); \
273 	} \
274 _NOTE(CONSTCOND) } while (0)
275 #else
276 #define	dprintf_ds(dd, fmt, ...)
277 #endif
278 
279 #ifdef	__cplusplus
280 }
281 #endif
282 
283 #endif /* _SYS_DSL_DATASET_H */
284