Depending on the changed options and the image format,
bdrv_amend_options() may take a significant amount of time. In these
cases, a way to be informed about the operation's status is desirable.
Since the operation is rather complex and may fundamentally change the
image, implementing it as AIO or a coroutine does not seem feasible. On
the other hand, implementing it as a block job would be significantly
more difficult than a simple callback and would not add benefits other
than progress report to the amending operation, because it should not
actually be run as a block job at all.
A callback may not be very pretty, but it's very easy to implement and
perfectly fits its purpose here.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: BenoƮt Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id:
1414404776-4919-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
notifier_with_return_list_add(&bs->before_write_notifiers, notifier);
}
-int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts)
+int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts,
+ BlockDriverAmendStatusCB *status_cb)
{
if (!bs->drv->bdrv_amend_options) {
return -ENOTSUP;
}
- return bs->drv->bdrv_amend_options(bs, opts);
+ return bs->drv->bdrv_amend_options(bs, opts, status_cb);
}
/* This function will be called by the bdrv_recurse_is_first_non_filter method
return 0;
}
-static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts)
+static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,
+ BlockDriverAmendStatusCB *status_cb)
{
BDRVQcowState *s = bs->opaque;
int old_version = s->qcow_version, new_version = old_version;
int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
-int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts);
+/* The units of offset and total_work_size may be chosen arbitrarily by the
+ * block driver; total_work_size may change during the course of the amendment
+ * operation */
+typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset,
+ int64_t total_work_size);
+int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts,
+ BlockDriverAmendStatusCB *status_cb);
/* external snapshots */
bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result,
BdrvCheckMode fix);
- int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts);
+ int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts,
+ BlockDriverAmendStatusCB *status_cb);
void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
goto out;
}
- ret = bdrv_amend_options(bs, opts);
+ ret = bdrv_amend_options(bs, opts, NULL);
if (ret < 0) {
error_report("Error while amending options: %s", strerror(-ret));
goto out;