From 00e30f05de1d19586345ec373970ef4c192c6270 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Tue, 1 Oct 2019 16:14:09 +0300 Subject: block/backup: use backup-top instead of write notifiers Drop write notifiers and use filter node instead. = Changes = 1. Add filter-node-name argument for backup qmp api. We have to do it in this commit, as 257 needs to be fixed. 2. There are no more write notifiers here, so is_write_notifier parameter is dropped from block-copy paths. 3. To sync with in-flight requests at job finish we now have drained removing of the filter, we don't need rw-lock. 4. Block-copy is now using BdrvChildren instead of BlockBackends 5. As backup-top owns these children, we also move block-copy state into backup-top's ownership. = Iotest changes = 56: op-blocker doesn't shoot now, as we set it on source, but then check on filter, when trying to start second backup. To keep the test we instead can catch another collision: both jobs will get 'drive0' job-id, as job-id parameter is unspecified. To prevent interleaving with file-posix locks (as they are dependent on config) let's use another target for second backup. Also, it's obvious now that we'd like to drop this op-blocker at all and add a test-case for two backups from one node (to different destinations) actually works. But not in these series. 141: Output changed: prepatch, "Node is in use" comes from bdrv_has_blk check inside qmp_blockdev_del. But we've dropped block-copy blk objects, so no more blk objects on source bs (job blk is on backup-top filter bs). New message is from op-blocker, which is the next check in qmp_blockdev_add. 257: The test wants to emulate guest write during backup. They should go to filter node, not to original source node, of course. Therefore we need to specify filter node name and use it. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-id: 20191001131409.14202-6-vsementsov@virtuozzo.com Reviewed-by: Max Reitz Signed-off-by: Max Reitz --- qapi/block-core.json | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'qapi/block-core.json') diff --git a/qapi/block-core.json b/qapi/block-core.json index 859acea014..f66553aac7 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -1450,6 +1450,11 @@ # list without user intervention. # Defaults to true. (Since 2.12) # +# @filter-node-name: the node name that should be assigned to the +# filter driver that the backup job inserts into the graph +# above node specified by @drive. If this option is not given, +# a node name is autogenerated. (Since: 4.2) +# # Note: @on-source-error and @on-target-error only affect background # I/O. If an error occurs during a guest write request, the device's # rerror/werror actions will be used. @@ -1463,7 +1468,8 @@ '*compress': 'bool', '*on-source-error': 'BlockdevOnError', '*on-target-error': 'BlockdevOnError', - '*auto-finalize': 'bool', '*auto-dismiss': 'bool' } } + '*auto-finalize': 'bool', '*auto-dismiss': 'bool', + '*filter-node-name': 'str' } } ## # @DriveBackup: -- cgit v1.2.3