[Qemu-devel] [PATCH v3 7/8] blockdev: add Abort transaction

[Stefan Hajnoczi <stefanha@redhat.com>]

The Abort action can be used to test QMP 'transaction' failure.  Add it
as the last action to exercise the .abort() and .cleanup() code paths
for all previous actions.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 blockdev.c       | 15 +++++++++++++++
 qapi-schema.json | 11 ++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/blockdev.c b/blockdev.c
index c386bb6..fcce219 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -973,6 +973,16 @@ static void drive_backup_abort(BlkTransactionState *common)
     }
 }
 
+static void abort_prepare(BlkTransactionState *common, Error **errp)
+{
+    error_setg(errp, "Transaction aborted using Abort action");
+}
+
+static void abort_commit(BlkTransactionState *common)
+{
+    assert(false); /* this action never succeeds */
+}
+
 static const BdrvActionOps actions[] = {
     [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC] = {
         .instance_size = sizeof(ExternalSnapshotState),
@@ -986,6 +996,11 @@ static const BdrvActionOps actions[] = {
         .commit = drive_backup_commit,
         .abort = drive_backup_abort,
     },
+    [TRANSACTION_ACTION_KIND_ABORT] = {
+        .instance_size = sizeof(BlkTransactionState),
+        .prepare = abort_prepare,
+        .commit = abort_commit,
+    },
 };
 
 /*
diff --git a/qapi-schema.json b/qapi-schema.json
index 9ca9352..15221a5 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1630,6 +1630,14 @@
             '*mode': 'NewImageMode', '*speed': 'int' } }
 
 ##
+# @Abort
+#
+# This action can be used to test transaction failure.
+###
+{ 'type': 'Abort',
+  'data': { } }
+
+##
 # @TransactionAction
 #
 # A discriminated record of operations that can be performed with
@@ -1638,7 +1646,8 @@
 { 'union': 'TransactionAction',
   'data': {
        'blockdev-snapshot-sync': 'BlockdevSnapshot',
-       'drive-backup': 'DriveBackup'
+       'drive-backup': 'DriveBackup',
+       'abort': 'Abort'
    } }
 
 ##
-- 
1.8.1.4