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  * Copyright (c) 2012 by Delphix. All rights reserved.
  24  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  25  */
  26 
  27 #ifndef _SYS_DSL_DATASET_H
  28 #define _SYS_DSL_DATASET_H
  29 
  30 #include <sys/dmu.h>
  31 #include <sys/spa.h>
  32 #include <sys/txg.h>
  33 #include <sys/zio.h>
  34 #include <sys/bplist.h>
  35 #include <sys/dsl_synctask.h>
  36 #include <sys/zfs_context.h>
  37 #include <sys/dsl_deadlist.h>
  38 
  39 #ifdef  __cplusplus
  40 extern "C" {
  41 #endif
  42 
  43 struct dsl_dataset;
  44 struct dsl_dir;
  45 struct dsl_pool;
  46 
  47 #define DS_FLAG_INCONSISTENT    (1ULL<<0)
  48 #define DS_IS_INCONSISTENT(ds)  \
  49         ((ds)->ds_phys->ds_flags & DS_FLAG_INCONSISTENT)
  50 /*
  51  * NB: nopromote can not yet be set, but we want support for it in this
  52  * on-disk version, so that we don't need to upgrade for it later.  It
  53  * will be needed when we implement 'zfs split' (where the split off
  54  * clone should not be promoted).
  55  */
  56 #define DS_FLAG_NOPROMOTE       (1ULL<<1)
  57 
  58 /*
  59  * DS_FLAG_UNIQUE_ACCURATE is set if ds_unique_bytes has been correctly
  60  * calculated for head datasets (starting with SPA_VERSION_UNIQUE_ACCURATE,
  61  * refquota/refreservations).
  62  */
  63 #define DS_FLAG_UNIQUE_ACCURATE (1ULL<<2)
  64 
  65 /*
  66  * DS_FLAG_DEFER_DESTROY is set after 'zfs destroy -d' has been called
  67  * on a dataset. This allows the dataset to be destroyed using 'zfs release'.
  68  */
  69 #define DS_FLAG_DEFER_DESTROY   (1ULL<<3)
  70 #define DS_IS_DEFER_DESTROY(ds) \
  71         ((ds)->ds_phys->ds_flags & DS_FLAG_DEFER_DESTROY)
  72 
  73 /*
  74  * DS_FLAG_CI_DATASET is set if the dataset contains a file system whose
  75  * name lookups should be performed case-insensitively.
  76  */
  77 #define DS_FLAG_CI_DATASET      (1ULL<<16)
  78 
  79 typedef struct dsl_dataset_phys {
  80         uint64_t ds_dir_obj;            /* DMU_OT_DSL_DIR */
  81         uint64_t ds_prev_snap_obj;      /* DMU_OT_DSL_DATASET */
  82         uint64_t ds_prev_snap_txg;
  83         uint64_t ds_next_snap_obj;      /* DMU_OT_DSL_DATASET */
  84         uint64_t ds_snapnames_zapobj;   /* DMU_OT_DSL_DS_SNAP_MAP 0 for snaps */
  85         uint64_t ds_num_children;       /* clone/snap children; ==0 for head */
  86         uint64_t ds_creation_time;      /* seconds since 1970 */
  87         uint64_t ds_creation_txg;
  88         uint64_t ds_deadlist_obj;       /* DMU_OT_DEADLIST */
  89         /*
  90          * ds_referenced_bytes, ds_compressed_bytes, and ds_uncompressed_bytes
  91          * include all blocks referenced by this dataset, including those
  92          * shared with any other datasets.
  93          */
  94         uint64_t ds_referenced_bytes;
  95         uint64_t ds_compressed_bytes;
  96         uint64_t ds_uncompressed_bytes;
  97         uint64_t ds_unique_bytes;       /* only relevant to snapshots */
  98         /*
  99          * The ds_fsid_guid is a 56-bit ID that can change to avoid
 100          * collisions.  The ds_guid is a 64-bit ID that will never
 101          * change, so there is a small probability that it will collide.
 102          */
 103         uint64_t ds_fsid_guid;
 104         uint64_t ds_guid;
 105         uint64_t ds_flags;              /* DS_FLAG_* */
 106         blkptr_t ds_bp;
 107         uint64_t ds_next_clones_obj;    /* DMU_OT_DSL_CLONES */
 108         uint64_t ds_props_obj;          /* DMU_OT_DSL_PROPS for snaps */
 109         uint64_t ds_userrefs_obj;       /* DMU_OT_USERREFS */
 110         uint64_t ds_pad[5]; /* pad out to 320 bytes for good measure */
 111 } dsl_dataset_phys_t;
 112 
 113 typedef struct dsl_dataset {
 114         /* Immutable: */
 115         struct dsl_dir *ds_dir;
 116         dsl_dataset_phys_t *ds_phys;
 117         dmu_buf_t *ds_dbuf;
 118         uint64_t ds_object;
 119         uint64_t ds_fsid_guid;
 120 
 121         /* only used in syncing context, only valid for non-snapshots: */
 122         struct dsl_dataset *ds_prev;
 123 
 124         /* has internal locking: */
 125         dsl_deadlist_t ds_deadlist;
 126         bplist_t ds_pending_deadlist;
 127 
 128         /* to protect against multiple concurrent incremental recv */
 129         kmutex_t ds_recvlock;
 130 
 131         /* protected by lock on pool's dp_dirty_datasets list */
 132         txg_node_t ds_dirty_link;
 133         list_node_t ds_synced_link;
 134 
 135         /*
 136          * ds_phys->ds_<accounting> is also protected by ds_lock.
 137          * Protected by ds_lock:
 138          */
 139         kmutex_t ds_lock;
 140         objset_t *ds_objset;
 141         uint64_t ds_userrefs;
 142 
 143         /*
 144          * ds_owner is protected by the ds_rwlock and the ds_lock
 145          */
 146         krwlock_t ds_rwlock;
 147         kcondvar_t ds_exclusive_cv;
 148         void *ds_owner;
 149 
 150         /* no locking; only for making guesses */
 151         uint64_t ds_trysnap_txg;
 152 
 153         /* for objset_open() */
 154         kmutex_t ds_opening_lock;
 155 
 156         uint64_t ds_reserved;   /* cached refreservation */
 157         uint64_t ds_quota;      /* cached refquota */
 158 
 159         kmutex_t ds_sendstream_lock;
 160         list_t ds_sendstreams;
 161 
 162         /* Protected by ds_lock; keep at end of struct for better locality */
 163         char ds_snapname[MAXNAMELEN];
 164 } dsl_dataset_t;
 165 
 166 struct dsl_ds_destroyarg {
 167         dsl_dataset_t *ds;              /* ds to destroy */
 168         dsl_dataset_t *rm_origin;       /* also remove our origin? */
 169         boolean_t is_origin_rm;         /* set if removing origin snap */
 170         boolean_t defer;                /* destroy -d requested? */
 171         boolean_t releasing;            /* destroying due to release? */
 172         boolean_t need_prep;            /* do we need to retry due to EBUSY? */
 173 };
 174 
 175 /*
 176  * The max length of a temporary tag prefix is the number of hex digits
 177  * required to express UINT64_MAX plus one for the hyphen.
 178  */
 179 #define MAX_TAG_PREFIX_LEN      17
 180 
 181 struct dsl_ds_holdarg {
 182         dsl_sync_task_group_t *dstg;
 183         const char *htag;
 184         char *snapname;
 185         boolean_t recursive;
 186         boolean_t gotone;
 187         boolean_t temphold;
 188         char failed[MAXPATHLEN];
 189 };
 190 
 191 #define dsl_dataset_is_snapshot(ds) \
 192         ((ds)->ds_phys->ds_num_children != 0)
 193 
 194 #define DS_UNIQUE_IS_ACCURATE(ds)       \
 195         (((ds)->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) != 0)
 196 
 197 int dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp);
 198 int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj,
 199     void *tag, dsl_dataset_t **);
 200 int dsl_dataset_own(const char *name, boolean_t inconsistentok,
 201     void *tag, dsl_dataset_t **dsp);
 202 int dsl_dataset_own_obj(struct dsl_pool *dp, uint64_t dsobj,
 203     boolean_t inconsistentok, void *tag, dsl_dataset_t **dsp);
 204 void dsl_dataset_name(dsl_dataset_t *ds, char *name);
 205 void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
 206 void dsl_dataset_disown(dsl_dataset_t *ds, void *tag);
 207 void dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag);
 208 boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok,
 209     void *tag);
 210 void dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *tag);
 211 void dsl_register_onexit_hold_cleanup(dsl_dataset_t *ds, const char *htag,
 212     minor_t minor);
 213 uint64_t dsl_dataset_create_sync(dsl_dir_t *pds, const char *lastname,
 214     dsl_dataset_t *origin, uint64_t flags, cred_t *, dmu_tx_t *);
 215 uint64_t dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
 216     uint64_t flags, dmu_tx_t *tx);
 217 int dsl_dataset_destroy(dsl_dataset_t *ds, void *tag, boolean_t defer);
 218 dsl_checkfunc_t dsl_dataset_destroy_check;
 219 dsl_syncfunc_t dsl_dataset_destroy_sync;
 220 dsl_syncfunc_t dsl_dataset_user_hold_sync;
 221 int dsl_dataset_snapshot_check(dsl_dataset_t *ds, const char *, dmu_tx_t *tx);
 222 void dsl_dataset_snapshot_sync(dsl_dataset_t *ds, const char *, dmu_tx_t *tx);
 223 int dsl_dataset_rename(char *name, const char *newname, boolean_t recursive);
 224 int dsl_dataset_promote(const char *name, char *conflsnap);
 225 int dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head,
 226     boolean_t force);
 227 int dsl_dataset_user_hold(char *dsname, char *snapname, char *htag,
 228     boolean_t recursive, boolean_t temphold, int cleanup_fd);
 229 int dsl_dataset_user_hold_for_send(dsl_dataset_t *ds, char *htag,
 230     boolean_t temphold);
 231 int dsl_dataset_user_release(char *dsname, char *snapname, char *htag,
 232     boolean_t recursive);
 233 int dsl_dataset_user_release_tmp(struct dsl_pool *dp, uint64_t dsobj,
 234     char *htag, boolean_t retry);
 235 int dsl_dataset_get_holds(const char *dsname, nvlist_t **nvp);
 236 
 237 blkptr_t *dsl_dataset_get_blkptr(dsl_dataset_t *ds);
 238 void dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx);
 239 
 240 spa_t *dsl_dataset_get_spa(dsl_dataset_t *ds);
 241 
 242 boolean_t dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds);
 243 
 244 void dsl_dataset_sync(dsl_dataset_t *os, zio_t *zio, dmu_tx_t *tx);
 245 
 246 void dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp,
 247     dmu_tx_t *tx);
 248 int dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp,
 249     dmu_tx_t *tx, boolean_t async);
 250 boolean_t dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
 251     uint64_t blk_birth);
 252 uint64_t dsl_dataset_prev_snap_txg(dsl_dataset_t *ds);
 253 
 254 void dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx);
 255 void dsl_dataset_stats(dsl_dataset_t *os, nvlist_t *nv);
 256 void dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat);
 257 void dsl_dataset_space(dsl_dataset_t *ds,
 258     uint64_t *refdbytesp, uint64_t *availbytesp,
 259     uint64_t *usedobjsp, uint64_t *availobjsp);
 260 uint64_t dsl_dataset_fsid_guid(dsl_dataset_t *ds);
 261 int dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
 262     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
 263 int dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, dsl_dataset_t *last,
 264     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
 265 boolean_t dsl_dataset_is_dirty(dsl_dataset_t *ds);
 266 
 267 int dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf);
 268 
 269 int dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
 270     uint64_t asize, uint64_t inflight, uint64_t *used,
 271     uint64_t *ref_rsrv);
 272 int dsl_dataset_set_quota(const char *dsname, zprop_source_t source,
 273     uint64_t quota);
 274 dsl_syncfunc_t dsl_dataset_set_quota_sync;
 275 int dsl_dataset_set_reservation(const char *dsname, zprop_source_t source,
 276     uint64_t reservation);
 277 
 278 int dsl_destroy_inconsistent(const char *dsname, void *arg);
 279 
 280 #ifdef ZFS_DEBUG
 281 #define dprintf_ds(ds, fmt, ...) do { \
 282         if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
 283         char *__ds_name = kmem_alloc(MAXNAMELEN, KM_SLEEP); \
 284         dsl_dataset_name(ds, __ds_name); \
 285         dprintf("ds=%s " fmt, __ds_name, __VA_ARGS__); \
 286         kmem_free(__ds_name, MAXNAMELEN); \
 287         } \
 288 _NOTE(CONSTCOND) } while (0)
 289 #else
 290 #define dprintf_ds(dd, fmt, ...)
 291 #endif
 292 
 293 #ifdef  __cplusplus
 294 }
 295 #endif
 296 
 297 #endif /* _SYS_DSL_DATASET_H */