commit: Add filter-node-name to block-commit

Management tools need to be able to know about every node in the graph
and need a way to address them. Changing the graph structure was okay
because libvirt doesn't really manage the node level yet, but future
libvirt versions need to deal with both new and old version of qemu.

This new option to blockdev-commit allows the client to set a node-name
for the automatically inserted filter driver, and at the same time
serves as a witness for a future libvirt that this version of qemu does
automatically insert a filter driver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>

diff --git a/block/commit.c b/block/commit.c
index f18026b61fb4b8d4d83fa6b314cc4aa63a5ec5dc..1e0f5318a43bafdd1a2120f0d87370373842d646 100644 (file)
--- a/block/commit.c
+++ b/block/commit.c
@@ -257,7 +257,7 @@ static BlockDriver bdrv_commit_top = {
 void commit_start(const char *job_id, BlockDriverState *bs,
                   BlockDriverState *base, BlockDriverState *top, int64_t speed,
                   BlockdevOnError on_error, const char *backing_file_str,
-                  Error **errp)
+                  const char *filter_node_name, Error **errp)
 {
     CommitBlockJob *s;
     BlockReopenQueue *reopen_queue = NULL;
@@ -310,7 +310,8 @@ void commit_start(const char *job_id, BlockDriverState *bs,
 
     /* Insert commit_top block node above top, so we can block consistent read
      * on the backing chain below it */
-    commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, NULL, 0, errp);
+    commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, filter_node_name, 0,
+                                         errp);
     if (commit_top_bs == NULL) {
         goto fail;
     }

diff --git a/block/mirror.c b/block/mirror.c
index f6d988df3db27ecf4ce542e2598590ad427ae48e..869212daacc60c61f9aaf2c3b2eab0bec1f37e24 100644 (file)
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -1246,6 +1246,7 @@ void mirror_start(const char *job_id, BlockDriverState *bs,
 void commit_active_start(const char *job_id, BlockDriverState *bs,
                          BlockDriverState *base, int creation_flags,
                          int64_t speed, BlockdevOnError on_error,
+                         const char *filter_node_name,
                          BlockCompletionFunc *cb, void *opaque, Error **errp,
                          bool auto_complete)
 {
@@ -1262,7 +1263,7 @@ void commit_active_start(const char *job_id, BlockDriverState *bs,
                      MIRROR_LEAVE_BACKING_CHAIN,
                      on_error, on_error, true, cb, opaque, &local_err,
                      &commit_active_job_driver, false, base, auto_complete,
-                     NULL);
+                     filter_node_name);
     if (local_err) {
         error_propagate(errp, local_err);
         goto error_restore_flags;

diff --git a/block/replication.c b/block/replication.c
index 91465cbae92c60b945233b2ca407eb78d7d3ddec..22f170fd33fe31e314b7fd9fb8d90623075417d5 100644 (file)
--- a/block/replication.c
+++ b/block/replication.c
@@ -644,7 +644,7 @@ static void replication_stop(ReplicationState *rs, bool failover, Error **errp)
         s->replication_state = BLOCK_REPLICATION_FAILOVER;
         commit_active_start(NULL, s->active_disk->bs, s->secondary_disk->bs,
                             BLOCK_JOB_INTERNAL, 0, BLOCKDEV_ON_ERROR_REPORT,
-                            replication_done, bs, errp, true);
+                            NULL, replication_done, bs, errp, true);
         break;
     default:
         aio_context_release(aio_context);

diff --git a/blockdev.c b/blockdev.c
index e592180b6286c7ac5817236c8c21322b02365d76..ff781d9df32b4017afbb0f17b8df960c1ca0a652 100644 (file)
--- a/blockdev.c
+++ b/blockdev.c
@@ -3032,6 +3032,7 @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
                       bool has_top, const char *top,
                       bool has_backing_file, const char *backing_file,
                       bool has_speed, int64_t speed,
+                      bool has_filter_node_name, const char *filter_node_name,
                       Error **errp)
 {
     BlockDriverState *bs;
@@ -3047,6 +3048,9 @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
     if (!has_speed) {
         speed = 0;
     }
+    if (!has_filter_node_name) {
+        filter_node_name = NULL;
+    }
 
     /* Important Note:
      *  libvirt relies on the DeviceNotFound error class in order to probe for
@@ -3121,8 +3125,8 @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
             goto out;
         }
         commit_active_start(has_job_id ? job_id : NULL, bs, base_bs,
-                            BLOCK_JOB_DEFAULT, speed, on_error, NULL, NULL,
-                            &local_err, false);
+                            BLOCK_JOB_DEFAULT, speed, on_error,
+                            filter_node_name, NULL, NULL, &local_err, false);
     } else {
         BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
         if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
@@ -3130,7 +3134,7 @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
         }
         commit_start(has_job_id ? job_id : NULL, bs, base_bs, top_bs, speed,
                      on_error, has_backing_file ? backing_file : NULL,
-                     &local_err);
+                     filter_node_name, &local_err);
     }
     if (local_err != NULL) {
         error_propagate(errp, local_err);

diff --git a/include/block/block_int.h b/include/block/block_int.h
index 563b30c3eec51cddd42e9fb79316f7e582896d4f..a57c0bfb552b5f55b557b4c1b6aedd19ca2007e6 100644 (file)
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -780,13 +780,16 @@ void stream_start(const char *job_id, BlockDriverState *bs,
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @on_error: The action to take upon error.
  * @backing_file_str: String to use as the backing file in @top's overlay
+ * @filter_node_name: The node name that should be assigned to the filter
+ * driver that the commit job inserts into the graph above @top. NULL means
+ * that a node name should be autogenerated.
  * @errp: Error object.
  *
  */
 void commit_start(const char *job_id, BlockDriverState *bs,
                   BlockDriverState *base, BlockDriverState *top, int64_t speed,
                   BlockdevOnError on_error, const char *backing_file_str,
-                  Error **errp);
+                  const char *filter_node_name, Error **errp);
 /**
  * commit_active_start:
  * @job_id: The id of the newly-created job, or %NULL to use the
@@ -797,6 +800,9 @@ void commit_start(const char *job_id, BlockDriverState *bs,
  *                  See @BlockJobCreateFlags
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @on_error: The action to take upon error.
+ * @filter_node_name: The node name that should be assigned to the filter
+ * driver that the commit job inserts into the graph above @bs. NULL means that
+ * a node name should be autogenerated.
  * @cb: Completion function for the job.
  * @opaque: Opaque pointer value passed to @cb.
  * @errp: Error object.
@@ -806,8 +812,9 @@ void commit_start(const char *job_id, BlockDriverState *bs,
 void commit_active_start(const char *job_id, BlockDriverState *bs,
                          BlockDriverState *base, int creation_flags,
                          int64_t speed, BlockdevOnError on_error,
-                         BlockCompletionFunc *cb,
-                         void *opaque, Error **errp, bool auto_complete);
+                         const char *filter_node_name,
+                         BlockCompletionFunc *cb, void *opaque, Error **errp,
+                         bool auto_complete);
 /*
  * mirror_start:
  * @job_id: The id of the newly-created job, or %NULL to use the

diff --git a/qapi/block-core.json b/qapi/block-core.json
index f0fa34c43468c9022162be079541ab87661ba4f3..5cc992fb8f8306551d7a0883992ac437bc23612b 100644 (file)
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1304,6 +1304,11 @@
 #
 # @speed:  #optional the maximum speed, in bytes per second
 #
+# @filter-node-name: #optional the node name that should be assigned to the
+#                    filter driver that the commit job inserts into the graph
+#                    above @top. If this option is not given, a node name is
+#                    autogenerated. (Since: 2.9)
+#
 # Returns: Nothing on success
 #          If commit or stream is already active on this device, DeviceInUse
 #          If @device does not exist, DeviceNotFound
@@ -1323,7 +1328,8 @@
 ##
 { 'command': 'block-commit',
   'data': { '*job-id': 'str', 'device': 'str', '*base': 'str', '*top': 'str',
-            '*backing-file': 'str', '*speed': 'int' } }
+            '*backing-file': 'str', '*speed': 'int',
+            '*filter-node-name': 'str' } }
 
 ##
 # @drive-backup:

diff --git a/qemu-img.c b/qemu-img.c
index 0c76d4caa7a8050d5fdf680e610f11c36771a64d..98b836b030a1bf336caffe3550bdca687a836350 100644 (file)
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -958,8 +958,8 @@ static int img_commit(int argc, char **argv)
     aio_context = bdrv_get_aio_context(bs);
     aio_context_acquire(aio_context);
     commit_active_start("commit", bs, base_bs, BLOCK_JOB_DEFAULT, 0,
-                        BLOCKDEV_ON_ERROR_REPORT, common_block_job_cb, &cbi,
-                        &local_err, false);
+                        BLOCKDEV_ON_ERROR_REPORT, NULL, common_block_job_cb,
+                        &cbi, &local_err, false);
     aio_context_release(aio_context);
     if (local_err) {
         goto done;