[Qemu-devel] [PULL 11/20] blockdev: add Abort transaction

[Kevin Wolf <kwolf@redhat.com>]

From: 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.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 blockdev.c       | 15 +++++++++++++++
 qapi-schema.json | 13 ++++++++++++-
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/blockdev.c b/blockdev.c
index 6200c0d..b3a57e0 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -963,6 +963,16 @@ 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),
@@ -975,6 +985,11 @@ static const BdrvActionOps actions[] = {
         .prepare = drive_backup_prepare,
         .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 714108d..6590307 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1660,6 +1660,16 @@
             '*on-target-error': 'BlockdevOnError' } }
 
 ##
+# @Abort
+#
+# This action can be used to test transaction failure.
+#
+# Since: 1.6
+###
+{ 'type': 'Abort',
+  'data': { } }
+
+##
 # @TransactionAction
 #
 # A discriminated record of operations that can be performed with
@@ -1668,7 +1678,8 @@
 { 'union': 'TransactionAction',
   'data': {
        'blockdev-snapshot-sync': 'BlockdevSnapshot',
-       'drive-backup': 'DriveBackup'
+       'drive-backup': 'DriveBackup',
+       'abort': 'Abort'
    } }
 
 ##
-- 
1.8.1.4