diff options
author | Stefan Hajnoczi <stefanha@redhat.com> | 2013-06-26 14:11:57 +0200 |
---|---|---|
committer | Kevin Wolf <kwolf@redhat.com> | 2013-07-15 09:49:00 +0200 |
commit | b53169eae06d6cf6f512a8b1fdd5424a0a6aab85 (patch) | |
tree | 91e2f6a6164ed11c8b53bda4c3e500d1ef2252cf /qmp-commands.hx | |
parent | c3cb8e77804313e1be99b5f28a34a346736707a5 (diff) |
blockdev: add sync mode to drive-backup QMP command
The drive-backup command is similar to the drive-mirror command, except
no guest data written after the command executes gets copied. Add a
sync mode argument which determines whether the entire disk is copied,
just allocated clusters, or only clusters being written to by the guest.
Currently only sync mode 'full' is supported - it copies the entire disk.
For read-only point-in-time snapshots we may only need sync mode 'none'
since the target can be a qcow2 file using the guest's disk as its
backing file (no need to copy the entire disk). Finally, sync mode
'top' is useful if we wish to preserve the backing chain.
Note that this patch just adds the sync mode argument to drive-backup.
It does not implement sync modes 'top' or 'none'. This patch is
necessary so we can add a drive-backup HMP command that behaves like the
existing drive-mirror HMP command and takes a sync mode.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'qmp-commands.hx')
-rw-r--r-- | qmp-commands.hx | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/qmp-commands.hx b/qmp-commands.hx index 362f0e1ef8..e075df423a 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -913,7 +913,7 @@ EQMP { .name = "drive-backup", - .args_type = "device:B,target:s,speed:i?,mode:s?,format:s?," + .args_type = "sync:s,device:B,target:s,speed:i?,mode:s?,format:s?," "on-source-error:s?,on-target-error:s?", .mhandler.cmd_new = qmp_marshal_input_drive_backup, }, @@ -939,6 +939,10 @@ Arguments: - "format": the format of the new destination, default is to probe if 'mode' is 'existing', else the format of the source (json-string, optional) +- "sync": what parts of the disk image should be copied to the destination; + possibilities include "full" for all the disk, "top" for only the sectors + allocated in the topmost image, or "none" to only replicate new I/O + (MirrorSyncMode). - "mode": whether and how QEMU should create a new image (NewImageMode, optional, default 'absolute-paths') - "speed": the maximum speed, in bytes per second (json-int, optional) |