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) 2013 by Delphix. All rights reserved.
  24  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  25  * Copyright (c) 2013 Steven Hartland. All rights reserved.
  26  */
  27 
  28 #ifndef _SYS_DSL_DATASET_H
  29 #define _SYS_DSL_DATASET_H
  30 
  31 #include <sys/dmu.h>
  32 #include <sys/spa.h>
  33 #include <sys/txg.h>
  34 #include <sys/zio.h>
  35 #include <sys/bplist.h>
  36 #include <sys/dsl_synctask.h>
  37 #include <sys/zfs_context.h>
  38 #include <sys/dsl_deadlist.h>
  39 #include <sys/refcount.h>
  40 
  41 #ifdef  __cplusplus
  42 extern "C" {
  43 #endif
  44 
  45 struct dsl_dataset;
  46 struct dsl_dir;
  47 struct dsl_pool;
  48 
  49 #define DS_FLAG_INCONSISTENT    (1ULL<<0)
  50 #define DS_IS_INCONSISTENT(ds)  \
  51         ((ds)->ds_phys->ds_flags & DS_FLAG_INCONSISTENT)
  52 /*
  53  * Note: nopromote can not yet be set, but we want support for it in this
  54  * on-disk version, so that we don't need to upgrade for it later.
  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 #define DS_CREATE_FLAG_NODIRTY  (1ULL<<24)
  80 
  81 typedef struct dsl_dataset_phys {
  82         uint64_t ds_dir_obj;            /* DMU_OT_DSL_DIR */
  83         uint64_t ds_prev_snap_obj;      /* DMU_OT_DSL_DATASET */
  84         uint64_t ds_prev_snap_txg;
  85         uint64_t ds_next_snap_obj;      /* DMU_OT_DSL_DATASET */
  86         uint64_t ds_snapnames_zapobj;   /* DMU_OT_DSL_DS_SNAP_MAP 0 for snaps */
  87         uint64_t ds_num_children;       /* clone/snap children; ==0 for head */
  88         uint64_t ds_creation_time;      /* seconds since 1970 */
  89         uint64_t ds_creation_txg;
  90         uint64_t ds_deadlist_obj;       /* DMU_OT_DEADLIST */
  91         /*
  92          * ds_referenced_bytes, ds_compressed_bytes, and ds_uncompressed_bytes
  93          * include all blocks referenced by this dataset, including those
  94          * shared with any other datasets.
  95          */
  96         uint64_t ds_referenced_bytes;
  97         uint64_t ds_compressed_bytes;
  98         uint64_t ds_uncompressed_bytes;
  99         uint64_t ds_unique_bytes;       /* only relevant to snapshots */
 100         /*
 101          * The ds_fsid_guid is a 56-bit ID that can change to avoid
 102          * collisions.  The ds_guid is a 64-bit ID that will never
 103          * change, so there is a small probability that it will collide.
 104          */
 105         uint64_t ds_fsid_guid;
 106         uint64_t ds_guid;
 107         uint64_t ds_flags;              /* DS_FLAG_* */
 108         blkptr_t ds_bp;
 109         uint64_t ds_next_clones_obj;    /* DMU_OT_DSL_CLONES */
 110         uint64_t ds_props_obj;          /* DMU_OT_DSL_PROPS for snaps */
 111         uint64_t ds_userrefs_obj;       /* DMU_OT_USERREFS */
 112         uint64_t ds_pad[5]; /* pad out to 320 bytes for good measure */
 113 } dsl_dataset_phys_t;
 114 
 115 typedef struct dsl_dataset {
 116         /* Immutable: */
 117         struct dsl_dir *ds_dir;
 118         dsl_dataset_phys_t *ds_phys;
 119         dmu_buf_t *ds_dbuf;
 120         uint64_t ds_object;
 121         uint64_t ds_fsid_guid;
 122 
 123         /* only used in syncing context, only valid for non-snapshots: */
 124         struct dsl_dataset *ds_prev;
 125 
 126         /* has internal locking: */
 127         dsl_deadlist_t ds_deadlist;
 128         bplist_t ds_pending_deadlist;
 129 
 130         /* protected by lock on pool's dp_dirty_datasets list */
 131         txg_node_t ds_dirty_link;
 132         list_node_t ds_synced_link;
 133 
 134         /*
 135          * ds_phys->ds_<accounting> is also protected by ds_lock.
 136          * Protected by ds_lock:
 137          */
 138         kmutex_t ds_lock;
 139         objset_t *ds_objset;
 140         uint64_t ds_userrefs;
 141         void *ds_owner;
 142 
 143         /*
 144          * Long holds prevent the ds from being destroyed; they allow the
 145          * ds to remain held even after dropping the dp_config_rwlock.
 146          * Owning counts as a long hold.  See the comments above
 147          * dsl_pool_hold() for details.
 148          */
 149         refcount_t ds_longholds;
 150 
 151         /* no locking; only for making guesses */
 152         uint64_t ds_trysnap_txg;
 153 
 154         /* for objset_open() */
 155         kmutex_t ds_opening_lock;
 156 
 157         uint64_t ds_reserved;   /* cached refreservation */
 158         uint64_t ds_quota;      /* cached refquota */
 159 
 160         kmutex_t ds_sendstream_lock;
 161         list_t ds_sendstreams;
 162 
 163         /* Protected by ds_lock; keep at end of struct for better locality */
 164         char ds_snapname[MAXNAMELEN];
 165 } dsl_dataset_t;
 166 
 167 /*
 168  * The max length of a temporary tag prefix is the number of hex digits
 169  * required to express UINT64_MAX plus one for the hyphen.
 170  */
 171 #define MAX_TAG_PREFIX_LEN      17
 172 
 173 #define dsl_dataset_is_snapshot(ds) \
 174         ((ds)->ds_phys->ds_num_children != 0)
 175 
 176 #define DS_UNIQUE_IS_ACCURATE(ds)       \
 177         (((ds)->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) != 0)
 178 
 179 int dsl_dataset_hold(struct dsl_pool *dp, const char *name, void *tag,
 180     dsl_dataset_t **dsp);
 181 int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj, void *tag,
 182     dsl_dataset_t **);
 183 void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
 184 int dsl_dataset_own(struct dsl_pool *dp, const char *name,
 185     void *tag, dsl_dataset_t **dsp);
 186 int dsl_dataset_own_obj(struct dsl_pool *dp, uint64_t dsobj,
 187     void *tag, dsl_dataset_t **dsp);
 188 void dsl_dataset_disown(dsl_dataset_t *ds, void *tag);
 189 void dsl_dataset_name(dsl_dataset_t *ds, char *name);
 190 boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, void *tag);
 191 uint64_t dsl_dataset_create_sync(dsl_dir_t *pds, const char *lastname,
 192     dsl_dataset_t *origin, uint64_t flags, cred_t *, dmu_tx_t *);
 193 uint64_t dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
 194     uint64_t flags, dmu_tx_t *tx);
 195 int dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors);
 196 int dsl_dataset_promote(const char *name, char *conflsnap);
 197 int dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head,
 198     boolean_t force);
 199 int dsl_dataset_rename_snapshot(const char *fsname,
 200     const char *oldsnapname, const char *newsnapname, boolean_t recursive);
 201 int dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
 202     minor_t cleanup_minor, const char *htag);
 203 
 204 blkptr_t *dsl_dataset_get_blkptr(dsl_dataset_t *ds);
 205 void dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx);
 206 
 207 spa_t *dsl_dataset_get_spa(dsl_dataset_t *ds);
 208 
 209 boolean_t dsl_dataset_modified_since_snap(dsl_dataset_t *ds,
 210     dsl_dataset_t *snap);
 211 
 212 void dsl_dataset_sync(dsl_dataset_t *os, zio_t *zio, dmu_tx_t *tx);
 213 
 214 void dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp,
 215     dmu_tx_t *tx);
 216 int dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp,
 217     dmu_tx_t *tx, boolean_t async);
 218 boolean_t dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
 219     uint64_t blk_birth);
 220 uint64_t dsl_dataset_prev_snap_txg(dsl_dataset_t *ds);
 221 
 222 void dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx);
 223 void dsl_dataset_stats(dsl_dataset_t *os, nvlist_t *nv);
 224 void dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat);
 225 void dsl_dataset_space(dsl_dataset_t *ds,
 226     uint64_t *refdbytesp, uint64_t *availbytesp,
 227     uint64_t *usedobjsp, uint64_t *availobjsp);
 228 uint64_t dsl_dataset_fsid_guid(dsl_dataset_t *ds);
 229 int dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
 230     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
 231 int dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, dsl_dataset_t *last,
 232     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
 233 boolean_t dsl_dataset_is_dirty(dsl_dataset_t *ds);
 234 
 235 int dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf);
 236 
 237 int dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
 238     uint64_t asize, uint64_t inflight, uint64_t *used,
 239     uint64_t *ref_rsrv);
 240 int dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
 241     uint64_t quota);
 242 int dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
 243     uint64_t reservation);
 244 
 245 boolean_t dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier);
 246 void dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag);
 247 void dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag);
 248 boolean_t dsl_dataset_long_held(dsl_dataset_t *ds);
 249 
 250 int dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
 251     dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx);
 252 void dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
 253     dsl_dataset_t *origin_head, dmu_tx_t *tx);
 254 int dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
 255     dmu_tx_t *tx, boolean_t recv);
 256 void dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
 257     dmu_tx_t *tx);
 258 
 259 void dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
 260     dmu_tx_t *tx);
 261 void dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds);
 262 int dsl_dataset_get_snapname(dsl_dataset_t *ds);
 263 int dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name,
 264     uint64_t *value);
 265 int dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx);
 266 void dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
 267     zprop_source_t source, uint64_t value, dmu_tx_t *tx);
 268 int dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result);
 269 
 270 #ifdef ZFS_DEBUG
 271 #define dprintf_ds(ds, fmt, ...) do { \
 272         if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
 273         char *__ds_name = kmem_alloc(MAXNAMELEN, KM_SLEEP); \
 274         dsl_dataset_name(ds, __ds_name); \
 275         dprintf("ds=%s " fmt, __ds_name, __VA_ARGS__); \
 276         kmem_free(__ds_name, MAXNAMELEN); \
 277         } \
 278 _NOTE(CONSTCOND) } while (0)
 279 #else
 280 #define dprintf_ds(dd, fmt, ...)
 281 #endif
 282 
 283 #ifdef  __cplusplus
 284 }
 285 #endif
 286 
 287 #endif /* _SYS_DSL_DATASET_H */