blockdev: Rename BlockdevAction -> TransactionAction

There's no reason to restrict transactions to operations related to
block devices, so rename the type now before schema introspection stops
us from doing so.

Also change the schema documentation of 'transaction' to not refer to
block devices or snapshots any more.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

blockdev.c

@@ -750,8 +750,8 @@ void do_commit(Monitor *mon, const QDict *qdict)
 
 static void blockdev_do_action(int kind, void *data, Error **errp)
 {
-    BlockdevAction action;
-    BlockdevActionList list;
+    TransactionAction action;
+    TransactionActionList list;
 
     action.kind = kind;
     action.data = data;
@@ -773,8 +773,8 @@ void qmp_blockdev_snapshot_sync(const char *device, const char *snapshot_file,
         .has_mode = has_mode,
         .mode = mode,
     };
-    blockdev_do_action(BLOCKDEV_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC, &snapshot,
-                       errp);
+    blockdev_do_action(TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
+                       &snapshot, errp);
 }
 
 
@@ -803,7 +803,7 @@ typedef struct BdrvActionOps {
  * Later it will be used in free().
  */
 struct BlkTransactionStates {
-    BlockdevAction *action;
+    TransactionAction *action;
     const BdrvActionOps *ops;
     QSIMPLEQ_ENTRY(BlkTransactionStates) entry;
 };
@@ -828,10 +828,10 @@ static void external_snapshot_prepare(BlkTransactionStates *common,
     enum NewImageMode mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
     ExternalSnapshotStates *states =
                              DO_UPCAST(ExternalSnapshotStates, common, common);
-    BlockdevAction *action = common->action;
+    TransactionAction *action = common->action;
 
     /* get parameters */
-    g_assert(action->kind == BLOCKDEV_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC);
+    g_assert(action->kind == TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC);
 
     device = action->blockdev_snapshot_sync->device;
     new_image_file = action->blockdev_snapshot_sync->snapshot_file;
@@ -927,7 +927,7 @@ static void external_snapshot_abort(BlkTransactionStates *common)
 }
 
 static const BdrvActionOps actions[] = {
-    [BLOCKDEV_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC] = {
+    [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC] = {
         .instance_size = sizeof(ExternalSnapshotStates),
         .prepare  = external_snapshot_prepare,
         .commit   = external_snapshot_commit,
@@ -940,9 +940,9 @@ static const BdrvActionOps actions[] = {
  *  then we do not pivot any of the devices in the group, and abandon the
  *  snapshots
  */
-void qmp_transaction(BlockdevActionList *dev_list, Error **errp)
+void qmp_transaction(TransactionActionList *dev_list, Error **errp)
 {
-    BlockdevActionList *dev_entry = dev_list;
+    TransactionActionList *dev_entry = dev_list;
     BlkTransactionStates *states, *next;
     Error *local_err = NULL;
 
@@ -954,7 +954,7 @@ void qmp_transaction(BlockdevActionList *dev_list, Error **errp)
 
     /* We don't do anything in this loop that commits us to the snapshot */
     while (NULL != dev_entry) {
-        BlockdevAction *dev_info = NULL;
+        TransactionAction *dev_info = NULL;
         const BdrvActionOps *ops;
 
         dev_info = dev_entry->value;

qapi-schema.json

@@ -1609,12 +1609,12 @@
             '*mode': 'NewImageMode' } }
 
 ##
-# @BlockdevAction
+# @TransactionAction
 #
 # A discriminated record of operations that can be performed with
 # @transaction.
 ##
-{ 'union': 'BlockdevAction',
+{ 'union': 'TransactionAction',
   'data': {
        'blockdev-snapshot-sync': 'BlockdevSnapshot'
    } }
@@ -1622,25 +1622,24 @@
 ##
 # @transaction
 #
-# 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 blockdev-snapshot-sync.
+# Executes a number of transactionable QMP commands atomically. If any
+# operation fails, then the entire set of actions will be abandoned and the
+# appropriate error returned.
 #
 #  List of:
-#  @BlockdevAction: information needed for the device snapshot
+#  @TransactionAction: information needed for the respective operation
 #
 # Returns: nothing on success
-#          If @device is not a valid block device, DeviceNotFound
+#          Errors depend on the operations of the transaction
 #
-# Note: The transaction aborts on the first failure.  Therefore, there will
-# be only one device or snapshot file returned in an error condition, and
+# Note: The transaction aborts on the first failure.  Therefore, there will be
+# information on only one failed operation returned in an error condition, and
 # subsequent actions will not have been attempted.
 #
 # Since 1.1
 ##
 { 'command': 'transaction',
-  'data': { 'actions': [ 'BlockdevAction' ] } }
+  'data': { 'actions': [ 'TransactionAction' ] } }
 
 ##
 # @blockdev-snapshot-sync