diff options
| -rw-r--r-- | blockdev.c | 116 | ||||
| -rw-r--r-- | qapi-schema.json | 19 | ||||
| -rw-r--r-- | qmp-commands.hx | 34 |
3 files changed, 160 insertions, 9 deletions
diff --git a/blockdev.c b/blockdev.c index 07dac05a2c..0fd30e2d8d 100644 --- a/blockdev.c +++ b/blockdev.c @@ -889,6 +889,117 @@ struct BlkTransactionState { QSIMPLEQ_ENTRY(BlkTransactionState) entry; }; +/* internal snapshot private data */ +typedef struct InternalSnapshotState { + BlkTransactionState common; + BlockDriverState *bs; + QEMUSnapshotInfo sn; +} InternalSnapshotState; + +static void internal_snapshot_prepare(BlkTransactionState *common, + Error **errp) +{ + const char *device; + const char *name; + BlockDriverState *bs; + QEMUSnapshotInfo old_sn, *sn; + bool ret; + qemu_timeval tv; + BlockdevSnapshotInternal *internal; + InternalSnapshotState *state; + int ret1; + + g_assert(common->action->kind == + TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC); + internal = common->action->blockdev_snapshot_internal_sync; + state = DO_UPCAST(InternalSnapshotState, common, common); + + /* 1. parse input */ + device = internal->device; + name = internal->name; + + /* 2. check for validation */ + bs = bdrv_find(device); + if (!bs) { + error_set(errp, QERR_DEVICE_NOT_FOUND, device); + return; + } + + if (!bdrv_is_inserted(bs)) { + error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device); + return; + } + + if (bdrv_is_read_only(bs)) { + error_set(errp, QERR_DEVICE_IS_READ_ONLY, device); + return; + } + + if (!bdrv_can_snapshot(bs)) { + error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, + bs->drv->format_name, device, "internal snapshot"); + return; + } + + if (!strlen(name)) { + error_setg(errp, "Name is empty"); + return; + } + + /* check whether a snapshot with name exist */ + ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn, errp); + if (error_is_set(errp)) { + return; + } else if (ret) { + error_setg(errp, + "Snapshot with name '%s' already exists on device '%s'", + name, device); + return; + } + + /* 3. take the snapshot */ + sn = &state->sn; + pstrcpy(sn->name, sizeof(sn->name), name); + qemu_gettimeofday(&tv); + sn->date_sec = tv.tv_sec; + sn->date_nsec = tv.tv_usec * 1000; + sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + + ret1 = bdrv_snapshot_create(bs, sn); + if (ret1 < 0) { + error_setg_errno(errp, -ret1, + "Failed to create snapshot '%s' on device '%s'", + name, device); + return; + } + + /* 4. succeed, mark a snapshot is created */ + state->bs = bs; +} + +static void internal_snapshot_abort(BlkTransactionState *common) +{ + InternalSnapshotState *state = + DO_UPCAST(InternalSnapshotState, common, common); + BlockDriverState *bs = state->bs; + QEMUSnapshotInfo *sn = &state->sn; + Error *local_error = NULL; + + if (!bs) { + return; + } + + if (bdrv_snapshot_delete(bs, sn->id_str, sn->name, &local_error) < 0) { + error_report("Failed to delete snapshot with id '%s' and name '%s' on " + "device '%s' in abort: %s", + sn->id_str, + sn->name, + bdrv_get_device_name(bs), + error_get_pretty(local_error)); + error_free(local_error); + } +} + /* external snapshot private data */ typedef struct ExternalSnapshotState { BlkTransactionState common; @@ -1072,6 +1183,11 @@ static const BdrvActionOps actions[] = { .prepare = abort_prepare, .commit = abort_commit, }, + [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC] = { + .instance_size = sizeof(InternalSnapshotState), + .prepare = internal_snapshot_prepare, + .abort = internal_snapshot_abort, + }, }; /* diff --git a/qapi-schema.json b/qapi-schema.json index 2b2c8bce07..77bbbf59cf 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -1686,6 +1686,22 @@ '*mode': 'NewImageMode' } } ## +# @BlockdevSnapshotInternal +# +# @device: the name of the device to generate the snapshot from +# +# @name: the name of the internal snapshot to be created +# +# Notes: In transaction, if @name is empty, or any snapshot matching @name +# exists, the operation will fail. Only some image formats support it, +# for example, qcow2, rbd, and sheepdog. +# +# Since: 1.7 +## +{ 'type': 'BlockdevSnapshotInternal', + 'data': { 'device': 'str', 'name': 'str' } } + +## # @DriveBackup # # @device: the name of the device which should be copied. @@ -1747,7 +1763,8 @@ 'data': { 'blockdev-snapshot-sync': 'BlockdevSnapshot', 'drive-backup': 'DriveBackup', - 'abort': 'Abort' + 'abort': 'Abort', + 'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal' } } ## diff --git a/qmp-commands.hx b/qmp-commands.hx index 008cad95a2..66701927af 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -1001,14 +1001,15 @@ SQMP transaction ----------- -Atomically operate on one or more block devices. The only supported -operation for now is snapshotting. If there is any failure performing -any of the operations, all snapshots for the group are abandoned, and -the original disks pre-snapshot attempt are used. +Atomically operate on one or more block devices. The only supported operations +for now are drive-backup, internal and external snapshotting. A list of +dictionaries is accepted, that contains the actions to be performed. +If there is any failure performing any of the operations, all operations +for the group are abandoned. -A list of dictionaries is accepted, that contains the actions to be performed. -For snapshots this is the device, the file to use for the new snapshot, -and the format. The default format, if not specified, is qcow2. +For external snapshots, the dictionary contains the device, the file to use for +the new snapshot, and the format. The default format, if not specified, is +qcow2. Each new snapshot defaults to being created by QEMU (wiping any contents if the file already exists), but it is also possible to reuse @@ -1017,6 +1018,17 @@ the new image file has the same contents as the current one; QEMU cannot perform any meaningful check. Typically this is achieved by using the current image file as the backing file for the new image. +On failure, the original disks pre-snapshot attempt will be used. + +For internal snapshots, the dictionary contains the device and the snapshot's +name. If an internal snapshot matching name already exists, the request will +be rejected. Only some image formats support it, for example, qcow2, rbd, +and sheepdog. + +On failure, qemu will try delete the newly created internal snapshot in the +transaction. When an I/O error occurs during deletion, the user needs to fix +it later with qemu-img or other command. + Arguments: actions array: @@ -1029,6 +1041,9 @@ actions array: - "format": format of new image (json-string, optional) - "mode": whether and how QEMU should create the snapshot file (NewImageMode, optional, default "absolute-paths") + When "type" is "blockdev-snapshot-internal-sync": + - "device": device name to snapshot (json-string) + - "name": name of the new snapshot (json-string) Example: @@ -1040,7 +1055,10 @@ Example: { 'type': 'blockdev-snapshot-sync', 'data' : { "device": "ide-hd1", "snapshot-file": "/some/place/my-image2", "mode": "existing", - "format": "qcow2" } } ] } } + "format": "qcow2" } }, + { 'type': 'blockdev-snapshot-internal-sync', 'data' : { + "device": "ide-hd2", + "name": "snapshot0" } } ] } } <- { "return": {} } EQMP |