mirror_zfs/include/sys/dsl_dataset.h
Andriy Gapon 8ca78ab002 OpenZFS 7600 - zfs rollback should pass target snapshot to kernel
Authored by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Ported-by: Giuseppe Di Natale <dinatale2@llnl.gov>

The existing kernel-side code only provides a method to rollback to a
latest snapshot, whatever it happens to be at the time when the rollback
is actually done.  That could be unsafe or confusing in environments
where concurrent DSL changes are possible as the resulting state could
correspond to a newer or older snapshot than the originally requested
one.
This change allows to amend that method such that the rollback is
performed only when the latest snapshot has a specific name.  That is,
if a new snapshot is concurrently created or the target snapshot is
destroyed, then no rollback is done and EXDEV error is returned.
New libzfs_core function lzc_rollback_to() is provided for the new
functionality.  libzfs is changed to use lzc_rollback_to() to implement
zfs rollback command.
Perhaps we should return different errors to distinguish the case where
the desired snapshot exists but it's not the latest snapshot and the
case where the desired snapshot does not exist.

OpenZFS-issue: https://www.illumos.org/issues/7600
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/3d645eb
Closes #6292
2017-07-04 15:29:52 -07:00

367 lines
13 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2011, 2015 by Delphix. All rights reserved.
* Copyright (c) 2011, 2014 by Delphix. All rights reserved.
* Copyright (c) 2013 Steven Hartland. All rights reserved.
* Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
*/
#ifndef _SYS_DSL_DATASET_H
#define _SYS_DSL_DATASET_H
#include <sys/dmu.h>
#include <sys/spa.h>
#include <sys/txg.h>
#include <sys/zio.h>
#include <sys/bplist.h>
#include <sys/dsl_synctask.h>
#include <sys/zfs_context.h>
#include <sys/dsl_deadlist.h>
#include <sys/refcount.h>
#include <sys/rrwlock.h>
#include <zfeature_common.h>
#ifdef __cplusplus
extern "C" {
#endif
struct dsl_dataset;
struct dsl_dir;
struct dsl_pool;
#define DS_FLAG_INCONSISTENT (1ULL<<0)
#define DS_IS_INCONSISTENT(ds) \
(dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT)
/*
* Do not allow this dataset to be promoted.
*/
#define DS_FLAG_NOPROMOTE (1ULL<<1)
/*
* DS_FLAG_UNIQUE_ACCURATE is set if ds_unique_bytes has been correctly
* calculated for head datasets (starting with SPA_VERSION_UNIQUE_ACCURATE,
* refquota/refreservations).
*/
#define DS_FLAG_UNIQUE_ACCURATE (1ULL<<2)
/*
* DS_FLAG_DEFER_DESTROY is set after 'zfs destroy -d' has been called
* on a dataset. This allows the dataset to be destroyed using 'zfs release'.
*/
#define DS_FLAG_DEFER_DESTROY (1ULL<<3)
#define DS_IS_DEFER_DESTROY(ds) \
(dsl_dataset_phys(ds)->ds_flags & DS_FLAG_DEFER_DESTROY)
/*
* DS_FIELD_* are strings that are used in the "extensified" dataset zap object.
* They should be of the format <reverse-dns>:<field>.
*/
/*
* This field's value is the object ID of a zap object which contains the
* bookmarks of this dataset. If it is present, then this dataset is counted
* in the refcount of the SPA_FEATURES_BOOKMARKS feature.
*/
#define DS_FIELD_BOOKMARK_NAMES "com.delphix:bookmarks"
/*
* This field is present (with value=0) if this dataset may contain large
* dnodes (>512B). If it is present, then this dataset is counted in the
* refcount of the SPA_FEATURE_LARGE_DNODE feature.
*/
#define DS_FIELD_LARGE_DNODE "org.zfsonlinux:large_dnode"
/*
* These fields are set on datasets that are in the middle of a resumable
* receive, and allow the sender to resume the send if it is interrupted.
*/
#define DS_FIELD_RESUME_FROMGUID "com.delphix:resume_fromguid"
#define DS_FIELD_RESUME_TONAME "com.delphix:resume_toname"
#define DS_FIELD_RESUME_TOGUID "com.delphix:resume_toguid"
#define DS_FIELD_RESUME_OBJECT "com.delphix:resume_object"
#define DS_FIELD_RESUME_OFFSET "com.delphix:resume_offset"
#define DS_FIELD_RESUME_BYTES "com.delphix:resume_bytes"
#define DS_FIELD_RESUME_LARGEBLOCK "com.delphix:resume_largeblockok"
#define DS_FIELD_RESUME_EMBEDOK "com.delphix:resume_embedok"
#define DS_FIELD_RESUME_COMPRESSOK "com.delphix:resume_compressok"
/*
* DS_FLAG_CI_DATASET is set if the dataset contains a file system whose
* name lookups should be performed case-insensitively.
*/
#define DS_FLAG_CI_DATASET (1ULL<<16)
#define DS_CREATE_FLAG_NODIRTY (1ULL<<24)
typedef struct dsl_dataset_phys {
uint64_t ds_dir_obj; /* DMU_OT_DSL_DIR */
uint64_t ds_prev_snap_obj; /* DMU_OT_DSL_DATASET */
uint64_t ds_prev_snap_txg;
uint64_t ds_next_snap_obj; /* DMU_OT_DSL_DATASET */
uint64_t ds_snapnames_zapobj; /* DMU_OT_DSL_DS_SNAP_MAP 0 for snaps */
uint64_t ds_num_children; /* clone/snap children; ==0 for head */
uint64_t ds_creation_time; /* seconds since 1970 */
uint64_t ds_creation_txg;
uint64_t ds_deadlist_obj; /* DMU_OT_DEADLIST */
/*
* ds_referenced_bytes, ds_compressed_bytes, and ds_uncompressed_bytes
* include all blocks referenced by this dataset, including those
* shared with any other datasets.
*/
uint64_t ds_referenced_bytes;
uint64_t ds_compressed_bytes;
uint64_t ds_uncompressed_bytes;
uint64_t ds_unique_bytes; /* only relevant to snapshots */
/*
* The ds_fsid_guid is a 56-bit ID that can change to avoid
* collisions. The ds_guid is a 64-bit ID that will never
* change, so there is a small probability that it will collide.
*/
uint64_t ds_fsid_guid;
uint64_t ds_guid;
uint64_t ds_flags; /* DS_FLAG_* */
blkptr_t ds_bp;
uint64_t ds_next_clones_obj; /* DMU_OT_DSL_CLONES */
uint64_t ds_props_obj; /* DMU_OT_DSL_PROPS for snaps */
uint64_t ds_userrefs_obj; /* DMU_OT_USERREFS */
uint64_t ds_pad[5]; /* pad out to 320 bytes for good measure */
} dsl_dataset_phys_t;
typedef struct dsl_dataset {
dmu_buf_user_t ds_dbu;
rrwlock_t ds_bp_rwlock; /* Protects ds_phys->ds_bp */
/* Immutable: */
struct dsl_dir *ds_dir;
dmu_buf_t *ds_dbuf;
uint64_t ds_object;
uint64_t ds_fsid_guid;
boolean_t ds_is_snapshot;
/* only used in syncing context, only valid for non-snapshots: */
struct dsl_dataset *ds_prev;
uint64_t ds_bookmarks; /* DMU_OTN_ZAP_METADATA */
/* has internal locking: */
dsl_deadlist_t ds_deadlist;
bplist_t ds_pending_deadlist;
/* protected by lock on pool's dp_dirty_datasets list */
txg_node_t ds_dirty_link;
list_node_t ds_synced_link;
/*
* ds_phys->ds_<accounting> is also protected by ds_lock.
* Protected by ds_lock:
*/
kmutex_t ds_lock;
objset_t *ds_objset;
uint64_t ds_userrefs;
void *ds_owner;
/*
* Long holds prevent the ds from being destroyed; they allow the
* ds to remain held even after dropping the dp_config_rwlock.
* Owning counts as a long hold. See the comments above
* dsl_pool_hold() for details.
*/
refcount_t ds_longholds;
/* no locking; only for making guesses */
uint64_t ds_trysnap_txg;
/* for objset_open() */
kmutex_t ds_opening_lock;
uint64_t ds_reserved; /* cached refreservation */
uint64_t ds_quota; /* cached refquota */
kmutex_t ds_sendstream_lock;
list_t ds_sendstreams;
/*
* When in the middle of a resumable receive, tracks how much
* progress we have made.
*/
uint64_t ds_resume_object[TXG_SIZE];
uint64_t ds_resume_offset[TXG_SIZE];
uint64_t ds_resume_bytes[TXG_SIZE];
/* Protected by our dsl_dir's dd_lock */
list_t ds_prop_cbs;
/*
* For ZFEATURE_FLAG_PER_DATASET features, set if this dataset
* uses this feature.
*/
uint8_t ds_feature_inuse[SPA_FEATURES];
/*
* Set if we need to activate the feature on this dataset this txg
* (used only in syncing context).
*/
uint8_t ds_feature_activation_needed[SPA_FEATURES];
/* Protected by ds_lock; keep at end of struct for better locality */
char ds_snapname[ZFS_MAX_DATASET_NAME_LEN];
} dsl_dataset_t;
static inline dsl_dataset_phys_t *
dsl_dataset_phys(dsl_dataset_t *ds)
{
return (ds->ds_dbuf->db_data);
}
/*
* The max length of a temporary tag prefix is the number of hex digits
* required to express UINT64_MAX plus one for the hyphen.
*/
#define MAX_TAG_PREFIX_LEN 17
#define dsl_dataset_is_snapshot(ds) \
(dsl_dataset_phys(ds)->ds_num_children != 0)
#define DS_UNIQUE_IS_ACCURATE(ds) \
((dsl_dataset_phys(ds)->ds_flags & DS_FLAG_UNIQUE_ACCURATE) != 0)
int dsl_dataset_hold(struct dsl_pool *dp, const char *name, void *tag,
dsl_dataset_t **dsp);
boolean_t dsl_dataset_try_add_ref(struct dsl_pool *dp, dsl_dataset_t *ds,
void *tag);
int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj, void *tag,
dsl_dataset_t **);
void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
int dsl_dataset_own(struct dsl_pool *dp, const char *name,
void *tag, dsl_dataset_t **dsp);
int dsl_dataset_own_obj(struct dsl_pool *dp, uint64_t dsobj,
void *tag, dsl_dataset_t **dsp);
void dsl_dataset_disown(dsl_dataset_t *ds, void *tag);
void dsl_dataset_name(dsl_dataset_t *ds, char *name);
boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, void *tag);
int dsl_dataset_namelen(dsl_dataset_t *ds);
boolean_t dsl_dataset_has_owner(dsl_dataset_t *ds);
uint64_t dsl_dataset_create_sync(dsl_dir_t *pds, const char *lastname,
dsl_dataset_t *origin, uint64_t flags, cred_t *, dmu_tx_t *);
uint64_t dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
uint64_t flags, dmu_tx_t *tx);
int dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors);
int dsl_dataset_promote(const char *name, char *conflsnap);
int dsl_dataset_rename_snapshot(const char *fsname,
const char *oldsnapname, const char *newsnapname, boolean_t recursive);
int dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
minor_t cleanup_minor, const char *htag);
blkptr_t *dsl_dataset_get_blkptr(dsl_dataset_t *ds);
spa_t *dsl_dataset_get_spa(dsl_dataset_t *ds);
boolean_t dsl_dataset_modified_since_snap(dsl_dataset_t *ds,
dsl_dataset_t *snap);
void dsl_dataset_sync(dsl_dataset_t *os, zio_t *zio, dmu_tx_t *tx);
void dsl_dataset_sync_done(dsl_dataset_t *os, dmu_tx_t *tx);
void dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp,
dmu_tx_t *tx);
int dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp,
dmu_tx_t *tx, boolean_t async);
int dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name,
uint64_t *value);
void dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx);
void dsl_dataset_stats(dsl_dataset_t *os, nvlist_t *nv);
void dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat);
void dsl_dataset_space(dsl_dataset_t *ds,
uint64_t *refdbytesp, uint64_t *availbytesp,
uint64_t *usedobjsp, uint64_t *availobjsp);
uint64_t dsl_dataset_fsid_guid(dsl_dataset_t *ds);
int dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
int dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, dsl_dataset_t *last,
uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
boolean_t dsl_dataset_is_dirty(dsl_dataset_t *ds);
int dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf);
int dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
uint64_t asize, uint64_t inflight, uint64_t *used,
uint64_t *ref_rsrv);
int dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
uint64_t quota);
int dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
uint64_t reservation);
boolean_t dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier,
uint64_t earlier_txg);
void dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag);
void dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag);
boolean_t dsl_dataset_long_held(dsl_dataset_t *ds);
int dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx);
void dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
dsl_dataset_t *origin_head, dmu_tx_t *tx);
int dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr);
void dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
dmu_tx_t *tx);
void dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
dmu_tx_t *tx);
void dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds);
int dsl_dataset_get_snapname(dsl_dataset_t *ds);
int dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name,
uint64_t *value);
int dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx,
boolean_t adj_cnt);
void dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
zprop_source_t source, uint64_t value, dmu_tx_t *tx);
void dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx);
boolean_t dsl_dataset_is_zapified(dsl_dataset_t *ds);
boolean_t dsl_dataset_has_resume_receive_state(dsl_dataset_t *ds);
int dsl_dataset_rollback(const char *fsname, const char *tosnap, void *owner,
nvlist_t *result);
void dsl_dataset_deactivate_feature(uint64_t dsobj,
spa_feature_t f, dmu_tx_t *tx);
#ifdef ZFS_DEBUG
#define dprintf_ds(ds, fmt, ...) do { \
if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
char *__ds_name = kmem_alloc(ZFS_MAX_DATASET_NAME_LEN, KM_SLEEP); \
dsl_dataset_name(ds, __ds_name); \
dprintf("ds=%s " fmt, __ds_name, __VA_ARGS__); \
kmem_free(__ds_name, ZFS_MAX_DATASET_NAME_LEN); \
} \
_NOTE(CONSTCOND) } while (0)
#else
#define dprintf_ds(dd, fmt, ...)
#endif
#ifdef __cplusplus
}
#endif
#endif /* _SYS_DSL_DATASET_H */