We will add other kinds of operation. Prepare for this by adjusting
the schema and renaming some types/variables.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
blockdev.c | 73 +++++++++++++++++++++++++++++------------------------
qapi-schema.json | 33 ++++++++++++++++--------
qmp-commands.hx | 51 ++++++++++++++++++++-----------------
3 files changed, 90 insertions(+), 67 deletions(-)
diff --git a/blockdev.c b/blockdev.c
index 96a893b..3c35553 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -716,31 +716,32 @@ void qmp_blockdev_snapshot_sync(const char *device, const
char *snapshot_file,
/* New and old BlockDriverState structs for group snapshots */
-typedef struct BlkGroupSnapshotStates {
+typedef struct BlkTransactionStates {
BlockDriverState *old_bs;
BlockDriverState *new_bs;
- QSIMPLEQ_ENTRY(BlkGroupSnapshotStates) entry;
-} BlkGroupSnapshotStates;
+ QSIMPLEQ_ENTRY(BlkTransactionStates) entry;
+} BlkTransactionStates;
/*
* 'Atomic' group snapshots. The snapshots are taken as a set, and if any fail
* then we do not pivot any of the devices in the group, and abandon the
* snapshots
*/
-void qmp_blockdev_group_snapshot_sync(SnapshotDevList *dev_list,
- Error **errp)
+void qmp_blockdev_transaction(BlockdevActionList *dev_list,
+ Error **errp)
{
int ret = 0;
- SnapshotDevList *dev_entry = dev_list;
- SnapshotDev *dev_info = NULL;
- BlkGroupSnapshotStates *states;
+ BlockdevActionList *dev_entry = dev_list;
+ BlockdevAction *dev_info = NULL;
+ BlkTransactionStates *states;
BlockDriver *proto_drv;
BlockDriver *drv;
int flags;
+ const char *device;
const char *format;
- const char *snapshot_file;
+ const char *new_image_file = NULL;
- QSIMPLEQ_HEAD(snap_bdrv_states, BlkGroupSnapshotStates) snap_bdrv_states;
+ QSIMPLEQ_HEAD(snap_bdrv_states, BlkTransactionStates) snap_bdrv_states;
QSIMPLEQ_INIT(&snap_bdrv_states);
/* drain all i/o before any snapshots */
@@ -751,18 +752,38 @@ void qmp_blockdev_group_snapshot_sync(SnapshotDevList
*dev_list,
dev_info = dev_entry->value;
dev_entry = dev_entry->next;
- states = g_malloc0(sizeof(BlkGroupSnapshotStates));
+ states = g_malloc0(sizeof(BlkTransactionStates));
QSIMPLEQ_INSERT_TAIL(&snap_bdrv_states, states, entry);
- states->old_bs = bdrv_find(dev_info->device);
+ switch (dev_info->kind) {
+ case BLOCKDEV_ACTION_KIND_SNAPSHOT:
+ device = dev_info->snapshot->device;
+ new_image_file = dev_info->snapshot->snapshot_file;
+ format = dev_info->snapshot->format;
+ assert(!(dev_info->snapshot->has_format && format));
+ break;
+ default:
+ abort();
+ }
+ if (!format) {
+ format = "qcow2";
+ }
+
+ drv = bdrv_find_format(format);
+ if (!drv) {
+ error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
+ goto delete_and_fail;
+ }
+
+ states->old_bs = bdrv_find(device);
if (!states->old_bs) {
- error_set(errp, QERR_DEVICE_NOT_FOUND, dev_info->device);
+ error_set(errp, QERR_DEVICE_NOT_FOUND, device);
goto delete_and_fail;
}
if (bdrv_in_use(states->old_bs)) {
- error_set(errp, QERR_DEVICE_IN_USE, dev_info->device);
+ error_set(errp, QERR_DEVICE_IN_USE, device);
goto delete_and_fail;
}
@@ -775,44 +796,30 @@ void qmp_blockdev_group_snapshot_sync(SnapshotDevList
*dev_list,
}
}
- snapshot_file = dev_info->snapshot_file;
-
flags = states->old_bs->open_flags;
- if (!dev_info->has_format) {
- format = "qcow2";
- } else {
- format = dev_info->format;
- }
-
- drv = bdrv_find_format(format);
- if (!drv) {
- error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
- goto delete_and_fail;
- }
-
- proto_drv = bdrv_find_protocol(snapshot_file);
+ proto_drv = bdrv_find_protocol(new_image_file);
if (!proto_drv) {
error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
goto delete_and_fail;
}
/* create new image w/backing file */
- ret = bdrv_img_create(snapshot_file, format,
+ ret = bdrv_img_create(new_image_file, format,
states->old_bs->filename,
states->old_bs->drv->format_name,
NULL, -1, flags);
if (ret) {
- error_set(errp, QERR_OPEN_FILE_FAILED, snapshot_file);
+ error_set(errp, QERR_OPEN_FILE_FAILED, new_image_file);
goto delete_and_fail;
}
/* We will manually add the backing_hd field to the bs later */
states->new_bs = bdrv_new("");
- ret = bdrv_open(states->new_bs, snapshot_file,
+ ret = bdrv_open(states->new_bs, new_image_file,
flags | BDRV_O_NO_BACKING, drv);
if (ret != 0) {
- error_set(errp, QERR_OPEN_FILE_FAILED, snapshot_file);
+ error_set(errp, QERR_OPEN_FILE_FAILED, new_image_file);
goto delete_and_fail;
}
}
diff --git a/qapi-schema.json b/qapi-schema.json
index 5f293c4..d2fbee3 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1118,7 +1118,7 @@
{ 'command': 'block_resize', 'data': { 'device': 'str', 'size': 'int' }}
##
-# @SnapshotDev
+# @BlockdevSnapshot
#
# @device: the name of the device to generate the snapshot from.
#
@@ -1126,19 +1126,30 @@
#
# @format: #optional the format of the snapshot image, default is 'qcow2'.
##
-{ 'type': 'SnapshotDev',
- 'data': {'device': 'str', 'snapshot-file': 'str', '*format': 'str' } }
+{ 'type': 'BlockdevSnapshot',
+ 'data': { 'device': 'str', 'snapshot-file': 'str', '*format': 'str' } }
+
+##
+# @BlockdevAction
+#
+# A discriminated record of operations that can be performed with
+# @blockdev-transaction.
+##
+{ 'union': 'BlockdevAction',
+ 'data': {
+ 'snapshot': 'BlockdevSnapshot'
+ } }
##
-# @blockdev-group-snapshot-sync
+# @blockdev-transaction
#
-# Generates a synchronous snapshot of a group of one or more block devices,
-# as atomically as possible. If the snapshot of any device in the group
-# fails, then the entire group snapshot will be abandoned and the
-# appropriate error returned.
+# Atomically operate on a group of one or more block devices. If
+# any operation fails, then the entire set of actions will be
+# abandoned and the appropriate error returned. The only operation
+# supported is currently snapshot.
#
# List of:
-# @SnapshotDev: information needed for the device snapshot
+# @BlockdevAction: information needed for the device snapshot
#
# Returns: nothing on success
# If @device is not a valid block device, DeviceNotFound
@@ -1152,8 +1163,8 @@
# returned in an error condition, and subsequent devices will not have been
# attempted.
##
-{ 'command': 'blockdev-group-snapshot-sync',
- 'data': { 'devlist': [ 'SnapshotDev' ] } }
+{ 'command': 'blockdev-transaction',
+ 'data': { 'actions': [ 'BlockdevAction' ] } }
##
# @blockdev-snapshot-sync
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 0c9bfac..ee05ec2 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -687,41 +687,46 @@ EQMP
.mhandler.cmd_new = qmp_marshal_input_block_job_cancel,
},
{
- .name = "blockdev-group-snapshot-sync",
- .args_type = "devlist:O",
- .params = "device:B,snapshot-file:s,format:s?",
- .mhandler.cmd_new = qmp_marshal_input_blockdev_group_snapshot_sync,
+ .name = "blockdev-transaction",
+ .args_type = "actions:O",
+ .mhandler.cmd_new = qmp_marshal_input_blockdev_transaction,
},
SQMP
-blockdev-group-snapshot-sync
+blockdev-transaction
----------------------
-Synchronous snapshot of one or more block devices. A list array input
-is accepted, that contains the device and snapshot file information for
-each device in group. The default format, if not specified, is qcow2.
-
-If there is any failure creating or opening a new snapshot, 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
+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.
+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.
Arguments:
-devlist array:
- - "device": device name to snapshot (json-string)
- - "snapshot-file": name of new image file (json-string)
- - "format": format of new image (json-string, optional)
+actions array:
+ - "type": the operation to perform. The only supported
+ value is "snapshot". (json-string)
+ - "data": a dictionary. The contents depend on the value
+ of "type". When "type" is "snapshot":
+ - "device": device name to snapshot (json-string)
+ - "snapshot-file": name of new image file (json-string)
+ - "format": format of new image (json-string, optional)
Example:
--> { "execute": "blockdev-group-snapshot-sync", "arguments":
- { "devlist": [{ "device": "ide-hd0",
- "snapshot-file": "/some/place/my-image",
- "format": "qcow2" },
- { "device": "ide-hd1",
- "snapshot-file": "/some/place/my-image2",
- "format": "qcow2" }] } }
+-> { "execute": "blockdev-transaction",
+ "arguments": { "actions": [
+ { 'type': 'snapshot, 'data' : { "device": "ide-hd0",
+ "snapshot-file":
"/some/place/my-image",
+ "format": "qcow2" } },
+ { 'type': 'snapshot, 'data' : { "device": "ide-hd1",
+ "snapshot-file":
"/some/place/my-image2",
+ "format": "qcow2",
+ "op": "snapshot" } } ] } }
<- { "return": {} }
EQMP
--
1.7.7.6
