mirror: Add 'job-id' parameter to 'blockdev-mirror' and 'drive-mirror'

This patch adds a new optional 'job-id' parameter to 'blockdev-mirror'
and 'drive-mirror', allowing the user to specify the ID of the block
job to be created.

The HMP 'drive_mirror' command remains unchanged.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/mirror.c

@@ -843,8 +843,8 @@ static const BlockJobDriver commit_active_job_driver = {
     .attached_aio_context   = mirror_attached_aio_context,
 };
 
-static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
-                             const char *replaces,
+static void mirror_start_job(const char *job_id, BlockDriverState *bs,
+                             BlockDriverState *target, const char *replaces,
                              int64_t speed, uint32_t granularity,
                              int64_t buf_size,
                              BlockMirrorBackingMode backing_mode,
@@ -873,7 +873,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
         buf_size = DEFAULT_MIRROR_BUF_SIZE;
     }
 
-    s = block_job_create(NULL, driver, bs, speed, cb, opaque, errp);
+    s = block_job_create(job_id, driver, bs, speed, cb, opaque, errp);
     if (!s) {
         return;
     }
@@ -906,8 +906,8 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
     qemu_coroutine_enter(s->common.co, s);
 }
 
-void mirror_start(BlockDriverState *bs, BlockDriverState *target,
-                  const char *replaces,
+void mirror_start(const char *job_id, BlockDriverState *bs,
+                  BlockDriverState *target, const char *replaces,
                   int64_t speed, uint32_t granularity, int64_t buf_size,
                   MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
                   BlockdevOnError on_source_error,
@@ -925,7 +925,7 @@ void mirror_start(BlockDriverState *bs, BlockDriverState *target,
     }
     is_none_mode = mode == MIRROR_SYNC_MODE_NONE;
     base = mode == MIRROR_SYNC_MODE_TOP ? backing_bs(bs) : NULL;
-    mirror_start_job(bs, target, replaces,
+    mirror_start_job(job_id, bs, target, replaces,
                      speed, granularity, buf_size, backing_mode,
                      on_source_error, on_target_error, unmap, cb, opaque, errp,
                      &mirror_job_driver, is_none_mode, base);
@@ -973,7 +973,8 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
         }
     }
 
-    mirror_start_job(bs, base, NULL, speed, 0, 0, MIRROR_LEAVE_BACKING_CHAIN,
+    mirror_start_job(NULL, bs, base, NULL, speed, 0, 0,
+                     MIRROR_LEAVE_BACKING_CHAIN,
                      on_error, on_error, false, cb, opaque, &local_err,
                      &commit_active_job_driver, false, base);
     if (local_err) {

blockdev.c

@@ -3422,7 +3422,7 @@ void qmp_blockdev_backup(const char *device, const char *target,
 /* Parameter check and block job starting for drive mirroring.
  * Caller should hold @device and @target's aio context (must be the same).
  **/
-static void blockdev_mirror_common(BlockDriverState *bs,
+static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
                                    BlockDriverState *target,
                                    bool has_replaces, const char *replaces,
                                    enum MirrorSyncMode sync,
@@ -3482,15 +3482,15 @@ static void blockdev_mirror_common(BlockDriverState *bs,
     /* pass the node name to replace to mirror start since it's loose coupling
      * and will allow to check whether the node still exist at mirror completion
      */
-    mirror_start(bs, target,
+    mirror_start(job_id, bs, target,
                  has_replaces ? replaces : NULL,
                  speed, granularity, buf_size, sync, backing_mode,
                  on_source_error, on_target_error, unmap,
                  block_job_cb, bs, errp);
 }
 
-void qmp_drive_mirror(const char *device, const char *target,
-                      bool has_format, const char *format,
+void qmp_drive_mirror(bool has_job_id, const char *job_id, const char *device,
+                      const char *target, bool has_format, const char *format,
                       bool has_node_name, const char *node_name,
                       bool has_replaces, const char *replaces,
                       enum MirrorSyncMode sync,
@@ -3634,7 +3634,7 @@ void qmp_drive_mirror(const char *device, const char *target,
 
     bdrv_set_aio_context(target_bs, aio_context);
 
-    blockdev_mirror_common(bs, target_bs,
+    blockdev_mirror_common(has_job_id ? job_id : NULL, bs, target_bs,
                            has_replaces, replaces, sync, backing_mode,
                            has_speed, speed,
                            has_granularity, granularity,
@@ -3649,7 +3649,8 @@ out:
     aio_context_release(aio_context);
 }
 
-void qmp_blockdev_mirror(const char *device, const char *target,
+void qmp_blockdev_mirror(bool has_job_id, const char *job_id,
+                         const char *device, const char *target,
                          bool has_replaces, const char *replaces,
                          MirrorSyncMode sync,
                          bool has_speed, int64_t speed,
@@ -3690,7 +3691,7 @@ void qmp_blockdev_mirror(const char *device, const char *target,
 
     bdrv_set_aio_context(target_bs, aio_context);
 
-    blockdev_mirror_common(bs, target_bs,
+    blockdev_mirror_common(has_job_id ? job_id : NULL, bs, target_bs,
                            has_replaces, replaces, sync, backing_mode,
                            has_speed, speed,
                            has_granularity, granularity,

hmp.c

@@ -1097,7 +1097,7 @@ void hmp_drive_mirror(Monitor *mon, const QDict *qdict)
         mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
     }
 
-    qmp_drive_mirror(device, filename, !!format, format,
+    qmp_drive_mirror(false, NULL, device, filename, !!format, format,
                      false, NULL, false, NULL,
                      full ? MIRROR_SYNC_MODE_FULL : MIRROR_SYNC_MODE_TOP,
                      true, mode, false, 0, false, 0, false, 0,

include/block/block_int.h

@@ -697,6 +697,8 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
                          void *opaque, Error **errp);
 /*
  * mirror_start:
+ * @job_id: The id of the newly-created job, or %NULL to use the
+ * device name of @bs.
  * @bs: Block device to operate on.
  * @target: Block device to write to.
  * @replaces: Block graph node name to replace once the mirror is done. Can
@@ -718,8 +720,8 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
  * manually completed.  At the end of a successful mirroring job,
  * @bs will be switched to read from @target.
  */
-void mirror_start(BlockDriverState *bs, BlockDriverState *target,
-                  const char *replaces,
+void mirror_start(const char *job_id, BlockDriverState *bs,
+                  BlockDriverState *target, const char *replaces,
                   int64_t speed, uint32_t granularity, int64_t buf_size,
                   MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
                   BlockdevOnError on_source_error,

qapi/block-core.json

@@ -1108,6 +1108,9 @@
 #
 # Start mirroring a block device's writes to a new destination.
 #
+# @job-id: #optional identifier for the newly-created block job. If
+#          omitted, the device name will be used. (Since 2.7)
+#
 # @device:  the name of the device whose writes should be mirrored.
 #
 # @target: the target of the new image. If the file exists, or if it
@@ -1160,8 +1163,8 @@
 # Since 1.3
 ##
 { 'command': 'drive-mirror',
-  'data': { 'device': 'str', 'target': 'str', '*format': 'str',
-            '*node-name': 'str', '*replaces': 'str',
+  'data': { '*job-id': 'str', 'device': 'str', 'target': 'str',
+            '*format': 'str', '*node-name': 'str', '*replaces': 'str',
             'sync': 'MirrorSyncMode', '*mode': 'NewImageMode',
             '*speed': 'int', '*granularity': 'uint32',
             '*buf-size': 'int', '*on-source-error': 'BlockdevOnError',
@@ -1243,6 +1246,9 @@
 #
 # Start mirroring a block device's writes to a new destination.
 #
+# @job-id: #optional identifier for the newly-created block job. If
+#          omitted, the device name will be used. (Since 2.7)
+#
 # @device: the name of the device whose writes should be mirrored.
 #
 # @target: the id or node-name of the block device to mirror to. This mustn't be
@@ -1279,7 +1285,7 @@
 # Since 2.6
 ##
 { 'command': 'blockdev-mirror',
-  'data': { 'device': 'str', 'target': 'str',
+  'data': { '*job-id': 'str', 'device': 'str', 'target': 'str',
             '*replaces': 'str',
             'sync': 'MirrorSyncMode',
             '*speed': 'int', '*granularity': 'uint32',

qmp-commands.hx

@@ -1656,8 +1656,8 @@ EQMP
 
     {
         .name       = "drive-mirror",
-        .args_type  = "sync:s,device:B,target:s,speed:i?,mode:s?,format:s?,"
-                      "node-name:s?,replaces:s?,"
+        .args_type  = "job-id:s?,sync:s,device:B,target:s,speed:i?,mode:s?,"
+                      "format:s?,node-name:s?,replaces:s?,"
                       "on-source-error:s?,on-target-error:s?,"
                       "unmap:b?,"
                       "granularity:i?,buf-size:i?",
@@ -1677,6 +1677,8 @@ of the source.
 
 Arguments:
 
+- "job-id": Identifier for the newly-created block job. If omitted,
+            the device name will be used. (json-string, optional)
 - "device": device name to operate on (json-string)
 - "target": name of new image file (json-string)
 - "format": format of new image (json-string, optional)
@@ -1720,7 +1722,7 @@ EQMP
 
     {
         .name       = "blockdev-mirror",
-        .args_type  = "sync:s,device:B,target:B,replaces:s?,speed:i?,"
+        .args_type  = "job-id:s?,sync:s,device:B,target:B,replaces:s?,speed:i?,"
                       "on-source-error:s?,on-target-error:s?,"
                       "granularity:i?,buf-size:i?",
         .mhandler.cmd_new = qmp_marshal_blockdev_mirror,
@@ -1735,6 +1737,8 @@ specifies the target of mirror operation.
 
 Arguments:
 
+- "job-id": Identifier for the newly-created block job. If omitted,
+            the device name will be used. (json-string, optional)
 - "device": device name to operate on (json-string)
 - "target": device name to mirror to (json-string)
 - "replaces": the block driver node name to replace when finished