commit: Support commit active layer

If active is top, it will be mirrored to base, (with block/mirror.c
code), then the image is switched when user completes the block job.

QMP documentation is updated.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Fam Zheng 2013-12-16 14:45:31 +08:00 committed by Stefan Hajnoczi
parent 03544a6e9e
commit 20a63d2cec
3 changed files with 21 additions and 4 deletions

View File

@ -481,6 +481,13 @@ immediate_exit:
bdrv_reopen(s->target, bdrv_get_flags(s->common.bs), NULL);
}
bdrv_swap(s->target, s->common.bs);
if (s->common.driver->job_type == BLOCK_JOB_TYPE_COMMIT) {
/* drop the bs loop chain formed by the swap: break the loop then
* trigger the unref from the top one */
BlockDriverState *p = s->base->backing_hd;
s->base->backing_hd = NULL;
bdrv_unref(p);
}
}
bdrv_unref(s->target);
block_job_completed(&s->common, ret);
@ -623,6 +630,10 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
BlockDriverCompletionFunc *cb,
void *opaque, Error **errp)
{
if (bdrv_reopen(base, bs->open_flags, errp)) {
return;
}
bdrv_ref(base);
mirror_start_job(bs, base, speed, 0, 0,
on_error, on_error, cb, opaque, errp,
&commit_active_job_driver, false, base);

View File

@ -1820,8 +1820,13 @@ void qmp_block_commit(const char *device,
return;
}
commit_start(bs, base_bs, top_bs, speed, on_error, block_job_cb, bs,
&local_err);
if (top_bs == bs) {
commit_active_start(bs, base_bs, speed, on_error, block_job_cb,
bs, &local_err);
} else {
commit_start(bs, base_bs, top_bs, speed, on_error, block_job_cb, bs,
&local_err);
}
if (local_err != NULL) {
error_propagate(errp, local_err);
return;

View File

@ -1967,9 +1967,11 @@
#
# @top: The file name of the backing image within the image chain,
# which contains the topmost data to be committed down.
# Note, the active layer as 'top' is currently unsupported.
#
# If top == base, that is an error.
# If top == active, the job will not be completed by itself,
# user needs to complete the job with the block-job-complete
# command after getting the ready event. (Since 2.0)
#
#
# @speed: #optional the maximum speed, in bytes per second
@ -1979,7 +1981,6 @@
# If @device does not exist, DeviceNotFound
# If image commit is not supported by this device, NotSupported
# If @base or @top is invalid, a generic error is returned
# If @top is the active layer, or omitted, a generic error is returned
# If @speed is invalid, InvalidParameter
#
# Since: 1.3