diff options
| author | Pavel Butsykin <pbutsykin@virtuozzo.com> | 2016-07-22 11:17:52 +0300 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2016-09-05 19:06:48 +0200 |
| commit | 13b9414b5798539e2dbb87a570d96184fe21edf4 (patch) | |
| tree | b78f6ea0b47ef741ec29787c15fe57edf2b98dcc /qapi | |
| parent | dc7a4a9ed170c19b4036cef2720d3e8fb551cc0f (diff) | |
| download | qemu-13b9414b5798539e2dbb87a570d96184fe21edf4.zip | |
drive-backup: added support for data compression
The idea is simple - backup is "written-once" data. It is written block
by block and it is large enough. It would be nice to save storage
space and compress it.
The patch adds a flag to the qmp/hmp drive-backup command which enables
block compression. Compression should be implemented in the format driver
to enable this feature.
There are some limitations of the format driver to allow compressed writes.
We can write data only once. Though for backup this is perfectly fine.
These limitations are maintained by the driver and the error will be
reported if we are doing something wrong.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'qapi')
| -rw-r--r-- | qapi/block-core.json | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/qapi/block-core.json b/qapi/block-core.json index 4c8cf057b5..300a68b63a 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -898,6 +898,9 @@ # Must be present if sync is "incremental", must NOT be present # otherwise. (Since 2.4) # +# @compress: #optional true to compress data, if the target format supports it. +# (default: false) (since 2.7) +# # @on-source-error: #optional the action to take on an error on the source, # default 'report'. 'stop' and 'enospc' can only be used # if the block device supports io-status (see BlockInfo). @@ -915,7 +918,7 @@ { 'struct': 'DriveBackup', 'data': { '*job-id': 'str', 'device': 'str', 'target': 'str', '*format': 'str', 'sync': 'MirrorSyncMode', '*mode': 'NewImageMode', - '*speed': 'int', '*bitmap': 'str', + '*speed': 'int', '*bitmap': 'str', '*compress': 'bool', '*on-source-error': 'BlockdevOnError', '*on-target-error': 'BlockdevOnError' } } |