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 #include <sys/refcount.h>
  39 
  40 #ifdef  __cplusplus
  41 extern "C" {
  42 #endif
  43 
  44 struct dsl_dataset;
  45 struct dsl_dir;
  46 struct dsl_pool;
  47 
  48 #define DS_HAS_PHYS(ds) \
  49         ((ds)->ds_dbuf != NULL && (ds)->ds_dbuf->db_data != NULL)
  50 
  51 #define DS_FLAG_INCONSISTENT    (1ULL<<0)
  52 #define DS_IS_INCONSISTENT(ds)  \
  53         ((ds)->ds_phys->ds_flags & DS_FLAG_INCONSISTENT)
  54 /*
  55  * Note: nopromote can not yet be set, but we want support for it in this
  56  * on-disk version, so that we don't need to upgrade for it later.
  57  */
  58 #define DS_FLAG_NOPROMOTE       (1ULL<<1)
  59 
  60 /*
  61  * DS_FLAG_UNIQUE_ACCURATE is set if ds_unique_bytes has been correctly
  62  * calculated for head datasets (starting with SPA_VERSION_UNIQUE_ACCURATE,
  63  * refquota/refreservations).
  64  */
  65 #define DS_FLAG_UNIQUE_ACCURATE (1ULL<<2)
  66 
  67 /*
  68  * DS_FLAG_DEFER_DESTROY is set after 'zfs destroy -d' has been called
  69  * on a dataset. This allows the dataset to be destroyed using 'zfs release'.
  70  */
  71 #define DS_FLAG_DEFER_DESTROY   (1ULL<<3)
  72 #define DS_IS_DEFER_DESTROY(ds) \
  73         ((ds)->ds_phys->ds_flags & DS_FLAG_DEFER_DESTROY)
  74 
  75 /*
  76  * DS_FLAG_CI_DATASET is set if the dataset contains a file system whose
  77  * name lookups should be performed case-insensitively.
  78  */
  79 #define DS_FLAG_CI_DATASET      (1ULL<<16)
  80 
  81 #define DS_CREATE_FLAG_NODIRTY  (1ULL<<24)
  82 
  83 typedef struct dsl_dataset_phys {
  84         uint64_t ds_dir_obj;            /* DMU_OT_DSL_DIR */
  85         uint64_t ds_prev_snap_obj;      /* DMU_OT_DSL_DATASET */
  86         uint64_t ds_prev_snap_txg;
  87         uint64_t ds_next_snap_obj;      /* DMU_OT_DSL_DATASET */
  88         uint64_t ds_snapnames_zapobj;   /* DMU_OT_DSL_DS_SNAP_MAP 0 for snaps */
  89         uint64_t ds_num_children;       /* clone/snap children; ==0 for head */
  90         uint64_t ds_creation_time;      /* seconds since 1970 */
  91         uint64_t ds_creation_txg;
  92         uint64_t ds_deadlist_obj;       /* DMU_OT_DEADLIST */
  93         /*
  94          * ds_referenced_bytes, ds_compressed_bytes, and ds_uncompressed_bytes
  95          * include all blocks referenced by this dataset, including those
  96          * shared with any other datasets.
  97          */
  98         uint64_t ds_referenced_bytes;
  99         uint64_t ds_compressed_bytes;
 100         uint64_t ds_uncompressed_bytes;
 101         uint64_t ds_unique_bytes;       /* only relevant to snapshots */
 102         /*
 103          * The ds_fsid_guid is a 56-bit ID that can change to avoid
 104          * collisions.  The ds_guid is a 64-bit ID that will never
 105          * change, so there is a small probability that it will collide.
 106          */
 107         uint64_t ds_fsid_guid;
 108         uint64_t ds_guid;
 109         uint64_t ds_flags;              /* DS_FLAG_* */
 110         blkptr_t ds_bp;
 111         uint64_t ds_next_clones_obj;    /* DMU_OT_DSL_CLONES */
 112         uint64_t ds_props_obj;          /* DMU_OT_DSL_PROPS for snaps */
 113         uint64_t ds_userrefs_obj;       /* DMU_OT_USERREFS */
 114         uint64_t ds_pad[5]; /* pad out to 320 bytes for good measure */
 115 } dsl_dataset_phys_t;
 116 
 117 typedef struct dsl_dataset_dbuf {
 118         uint8_t dsdb_pad[offsetof(dmu_buf_t, db_data)];
 119         dsl_dataset_phys_t *dsdb_data;
 120 } dsl_dataset_dbuf_t;
 121 
 122 typedef struct dsl_dataset {
 123         dmu_buf_user_t db_evict;
 124 
 125         /* Immutable: */
 126         struct dsl_dir *ds_dir;
 127         union {
 128                 dmu_buf_t *ds_dmu_db;
 129                 dsl_dataset_dbuf_t *ds_db;
 130         } ds_db_u;
 131         uint64_t ds_object;
 132         uint64_t ds_fsid_guid;
 133 
 134         /* only used in syncing context, only valid for non-snapshots: */
 135         struct dsl_dataset *ds_prev;
 136 
 137         /* has internal locking: */
 138         dsl_deadlist_t ds_deadlist;
 139         bplist_t ds_pending_deadlist;
 140 
 141         /* protected by lock on pool's dp_dirty_datasets list */
 142         txg_node_t ds_dirty_link;
 143         list_node_t ds_synced_link;
 144 
 145         /*
 146          * ds_phys->ds_<accounting> is also protected by ds_lock.
 147          * Protected by ds_lock:
 148          */
 149         kmutex_t ds_lock;
 150         objset_t *ds_objset;
 151         uint64_t ds_userrefs;
 152         void *ds_owner;
 153 
 154         /*
 155          * Long holds prevent the ds from being destroyed; they allow the
 156          * ds to remain held even after dropping the dp_config_rwlock.
 157          * Owning counts as a long hold.  See the comments above
 158          * dsl_pool_hold() for details.
 159          */
 160         refcount_t ds_longholds;
 161 
 162         /* no locking; only for making guesses */
 163         uint64_t ds_trysnap_txg;
 164 
 165         /* for objset_open() */
 166         kmutex_t ds_opening_lock;
 167 
 168         uint64_t ds_reserved;   /* cached refreservation */
 169         uint64_t ds_quota;      /* cached refquota */
 170 
 171         kmutex_t ds_sendstream_lock;
 172         list_t ds_sendstreams;
 173 
 174         /* Protected by ds_lock; keep at end of struct for better locality */
 175         char ds_snapname[MAXNAMELEN];
 176 } dsl_dataset_t;
 177 
 178 /* See sys/dmu.h:dmu_buf_user_t for why we have these. */
 179 #define ds_dbuf ds_db_u.ds_dmu_db
 180 #define ds_phys ds_db_u.ds_db->dsdb_data
 181 
 182 struct dsl_ds_destroyarg {
 183         dsl_dataset_t *ds;              /* ds to destroy */
 184         dsl_dataset_t *rm_origin;       /* also remove our origin? */
 185         boolean_t is_origin_rm;         /* set if removing origin snap */
 186         boolean_t defer;                /* destroy -d requested? */
 187         boolean_t releasing;            /* destroying due to release? */
 188         boolean_t need_prep;            /* do we need to retry due to EBUSY? */
 189 };
 190 
 191 /*
 192  * The max length of a temporary tag prefix is the number of hex digits
 193  * required to express UINT64_MAX plus one for the hyphen.
 194  */
 195 #define MAX_TAG_PREFIX_LEN      17
 196 
 197 #define dsl_dataset_is_snapshot(ds) \
 198         ((ds)->ds_phys->ds_num_children != 0)
 199 
 200 #define DS_UNIQUE_IS_ACCURATE(ds)       \
 201         (((ds)->ds_phys->ds_flags & DS_FLAG_UNIQUE_ACCURATE) != 0)
 202 
 203 int dsl_dataset_hold(struct dsl_pool *dp, const char *name, void *tag,
 204     dsl_dataset_t **dsp);
 205 int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj, void *tag,
 206     dsl_dataset_t **);
 207 void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
 208 int dsl_dataset_own(struct dsl_pool *dp, const char *name,
 209     void *tag, dsl_dataset_t **dsp);
 210 int dsl_dataset_own_obj(struct dsl_pool *dp, uint64_t dsobj,
 211     void *tag, dsl_dataset_t **dsp);
 212 void dsl_dataset_disown(dsl_dataset_t *ds, void *tag);
 213 void dsl_dataset_name(dsl_dataset_t *ds, char *name);
 214 boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, void *tag);
 215 void dsl_register_onexit_hold_cleanup(dsl_dataset_t *ds, const char *htag,
 216     minor_t minor);
 217 uint64_t dsl_dataset_create_sync(dsl_dir_t *pds, const char *lastname,
 218     dsl_dataset_t *origin, uint64_t flags, cred_t *, dmu_tx_t *);
 219 uint64_t dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
 220     uint64_t flags, dmu_tx_t *tx);
 221 int dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors);
 222 int dsl_dataset_promote(const char *name, char *conflsnap);
 223 int dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head,
 224     boolean_t force);
 225 int dsl_dataset_rename_snapshot(const char *fsname,
 226     const char *oldsnapname, const char *newsnapname, boolean_t recursive);
 227 int dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
 228     minor_t cleanup_minor, const char *htag);
 229 
 230 blkptr_t *dsl_dataset_get_blkptr(dsl_dataset_t *ds);
 231 void dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx);
 232 
 233 spa_t *dsl_dataset_get_spa(dsl_dataset_t *ds);
 234 
 235 boolean_t dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds);
 236 
 237 void dsl_dataset_sync(dsl_dataset_t *os, zio_t *zio, dmu_tx_t *tx);
 238 
 239 void dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp,
 240     dmu_tx_t *tx);
 241 int dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp,
 242     dmu_tx_t *tx, boolean_t async);
 243 boolean_t dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
 244     uint64_t blk_birth);
 245 uint64_t dsl_dataset_prev_snap_txg(dsl_dataset_t *ds);
 246 
 247 void dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx);
 248 void dsl_dataset_stats(dsl_dataset_t *os, nvlist_t *nv);
 249 void dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat);
 250 void dsl_dataset_space(dsl_dataset_t *ds,
 251     uint64_t *refdbytesp, uint64_t *availbytesp,
 252     uint64_t *usedobjsp, uint64_t *availobjsp);
 253 uint64_t dsl_dataset_fsid_guid(dsl_dataset_t *ds);
 254 int dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
 255     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
 256 int dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, dsl_dataset_t *last,
 257     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
 258 boolean_t dsl_dataset_is_dirty(dsl_dataset_t *ds);
 259 
 260 int dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf);
 261 
 262 int dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
 263     uint64_t asize, uint64_t inflight, uint64_t *used,
 264     uint64_t *ref_rsrv);
 265 int dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
 266     uint64_t quota);
 267 int dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
 268     uint64_t reservation);
 269 
 270 boolean_t dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier);
 271 void dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag);
 272 void dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag);
 273 boolean_t dsl_dataset_long_held(dsl_dataset_t *ds);
 274 
 275 int dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
 276     dsl_dataset_t *origin_head, boolean_t force);
 277 void dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
 278     dsl_dataset_t *origin_head, dmu_tx_t *tx);
 279 int dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
 280     dmu_tx_t *tx);
 281 void dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
 282     dmu_tx_t *tx);
 283 
 284 void dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
 285     dmu_tx_t *tx);
 286 void dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds);
 287 int dsl_dataset_get_snapname(dsl_dataset_t *ds);
 288 int dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name,
 289     uint64_t *value);
 290 int dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx);
 291 void dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
 292     zprop_source_t source, uint64_t value, dmu_tx_t *tx);
 293 int dsl_dataset_rollback(const char *fsname);
 294 
 295 #ifdef ZFS_DEBUG
 296 #define dprintf_ds(ds, fmt, ...) do { \
 297         if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
 298         char *__ds_name = kmem_alloc(MAXNAMELEN, KM_SLEEP); \
 299         dsl_dataset_name(ds, __ds_name); \
 300         dprintf("ds=%s " fmt, __ds_name, __VA_ARGS__); \
 301         kmem_free(__ds_name, MAXNAMELEN); \
 302         } \
 303 _NOTE(CONSTCOND) } while (0)
 304 #else
 305 #define dprintf_ds(dd, fmt, ...)
 306 #endif
 307 
 308 #ifdef  __cplusplus
 309 }
 310 #endif
 311 
 312 #endif /* _SYS_DSL_DATASET_H */