@@ -1309,11 +1309,14 @@ static void bdrv_backing_detach(BdrvChild *c)
}
static int bdrv_backing_update_filename(BdrvChild *c, BlockDriverState *base,
- const char *filename, Error **errp)
+ const char *filename,
+ bool backing_file_format_no_protocol,
+ Error **errp)
{
BlockDriverState *parent = c->opaque;
bool read_only = bdrv_is_read_only(parent);
int ret;
+ const char *format_name;
GLOBAL_STATE_CODE();
if (read_only) {
@@ -1323,9 +1326,23 @@ static int bdrv_backing_update_filename(BdrvChild *c, BlockDriverState *base,
}
}
- ret = bdrv_change_backing_file(parent, filename,
- base->drv ? base->drv->format_name : "",
- false);
+ if (base->drv) {
+ /*
+ * If the new base image doesn't have a format driver layer, which we
+ * detect by the fact that @base is a protocol driver, we record
+ * 'raw' as the format instead of putting the protocol name as the
+ * backing format
+ */
+ if (backing_file_format_no_protocol && base->drv->protocol_name) {
+ format_name = "raw";
+ } else {
+ format_name = base->drv->format_name;
+ }
+ } else {
+ format_name = "";
+ }
+
+ ret = bdrv_change_backing_file(parent, filename, format_name, false);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not update backing file link");
}
@@ -1479,10 +1496,14 @@ static void GRAPH_WRLOCK bdrv_child_cb_detach(BdrvChild *child)
}
static int bdrv_child_cb_update_filename(BdrvChild *c, BlockDriverState *base,
- const char *filename, Error **errp)
+ const char *filename,
+ bool backing_file_format_no_protocol,
+ Error **errp)
{
if (c->role & BDRV_CHILD_COW) {
- return bdrv_backing_update_filename(c, base, filename, errp);
+ return bdrv_backing_update_filename(c, base, filename,
+ backing_file_format_no_protocol,
+ errp);
}
return 0;
}
@@ -5961,7 +5982,8 @@ void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base)
*
*/
int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base,
- const char *backing_file_str)
+ const char *backing_file_str,
+ bool backing_file_format_no_protocol)
{
BlockDriverState *explicit_top = top;
bool update_inherits_from;
@@ -6027,6 +6049,7 @@ int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base,
if (c->klass->update_filename) {
ret = c->klass->update_filename(c, base, backing_file_str,
+ backing_file_format_no_protocol,
&local_err);
if (ret < 0) {
/*
@@ -42,6 +42,7 @@ typedef struct CommitBlockJob {
bool base_read_only;
bool chain_frozen;
char *backing_file_str;
+ bool backing_file_format_no_protocol;
} CommitBlockJob;
static int commit_prepare(Job *job)
@@ -61,7 +62,8 @@ static int commit_prepare(Job *job)
/* FIXME: bdrv_drop_intermediate treats total failures and partial failures
* identically. Further work is needed to disambiguate these cases. */
return bdrv_drop_intermediate(s->commit_top_bs, s->base_bs,
- s->backing_file_str);
+ s->backing_file_str,
+ s->backing_file_format_no_protocol);
}
static void commit_abort(Job *job)
@@ -254,6 +256,7 @@ void commit_start(const char *job_id, BlockDriverState *bs,
BlockDriverState *base, BlockDriverState *top,
int creation_flags, int64_t speed,
BlockdevOnError on_error, const char *backing_file_str,
+ bool backing_file_format_no_protocol,
const char *filter_node_name, Error **errp)
{
CommitBlockJob *s;
@@ -408,6 +411,7 @@ void commit_start(const char *job_id, BlockDriverState *bs,
blk_set_disable_request_queuing(s->top, true);
s->backing_file_str = g_strdup(backing_file_str);
+ s->backing_file_format_no_protocol = backing_file_format_no_protocol;
s->on_error = on_error;
trace_commit_start(bs, base, top, s);
@@ -2555,6 +2555,8 @@ void qmp_block_commit(const char *job_id, const char *device,
const char *top_node,
const char *top,
const char *backing_file,
+ bool has_backing_file_format_no_protocol,
+ bool backing_file_format_no_protocol,
bool has_speed, int64_t speed,
bool has_on_error, BlockdevOnError on_error,
const char *filter_node_name,
@@ -2585,6 +2587,9 @@ void qmp_block_commit(const char *job_id, const char *device,
if (has_auto_dismiss && !auto_dismiss) {
job_flags |= JOB_MANUAL_DISMISS;
}
+ if (!has_backing_file_format_no_protocol) {
+ backing_file_format_no_protocol = false;
+ }
/* Important Note:
* libvirt relies on the DeviceNotFound error class in order to probe for
@@ -2727,6 +2732,7 @@ void qmp_block_commit(const char *job_id, const char *device,
}
commit_start(job_id, bs, base_bs, top_bs, job_flags,
speed, on_error, backing_file,
+ backing_file_format_no_protocol,
filter_node_name, &local_err);
}
if (local_err != NULL) {
@@ -145,7 +145,8 @@ int GRAPH_RDLOCK bdrv_make_empty(BdrvChild *c, Error **errp);
void bdrv_register(BlockDriver *bdrv);
int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base,
- const char *backing_file_str);
+ const char *backing_file_str,
+ bool backing_file_format_no_protocol);
BlockDriverState * GRAPH_RDLOCK
bdrv_find_overlay(BlockDriverState *active, BlockDriverState *bs);
@@ -985,7 +985,9 @@ struct BdrvChildClass {
* can update its reference.
*/
int (*update_filename)(BdrvChild *child, BlockDriverState *new_base,
- const char *filename, Error **errp);
+ const char *filename,
+ bool backing_file_format_no_protocol,
+ Error **errp);
bool (*change_aio_ctx)(BdrvChild *child, AioContext *ctx,
GHashTable *visited, Transaction *tran,
@@ -82,6 +82,8 @@ void stream_start(const char *job_id, BlockDriverState *bs,
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
* @on_error: The action to take upon error.
* @backing_file_str: String to use as the backing file in @top's overlay
+ * @backing_file_format_no_protocol: Use format name instead of potental
+ * protocol name as backing image format
* @filter_node_name: The node name that should be assigned to the filter
* driver that the commit job inserts into the graph above @top. NULL means
* that a node name should be autogenerated.
@@ -92,6 +94,7 @@ void commit_start(const char *job_id, BlockDriverState *bs,
BlockDriverState *base, BlockDriverState *top,
int creation_flags, int64_t speed,
BlockdevOnError on_error, const char *backing_file_str,
+ bool backing_file_format_no_protocol,
const char *filter_node_name, Error **errp);
/**
* commit_active_start:
@@ -1810,6 +1810,14 @@
# Care should be taken when specifying the string, to specify a
# valid filename or protocol. (Since 2.1)
#
+# @backing-file-format-no-protocol: If true always use a 'format' driver name
+# for the 'backing file format' field if updating the image header of the
+# overlay of 'top'. Otherwise the real name of the driver of the backing
+# image may be used which may be a protocol driver.
+#
+# Can be used also when no image header will be updated.
+# (default: false; since: 9.0)
+#
# @speed: the maximum speed, in bytes per second
#
# @on-error: the action to take on an error. 'ignore' means that the
@@ -1856,7 +1864,8 @@
'*base': { 'type': 'str', 'features': [ 'deprecated' ] },
'*top-node': 'str',
'*top': { 'type': 'str', 'features': [ 'deprecated' ] },
- '*backing-file': 'str', '*speed': 'int',
+ '*backing-file': 'str', '*backing-file-format-no-protocol': 'bool',
+ '*speed': 'int',
'*on-error': 'BlockdevOnError',
'*filter-node-name': 'str',
'*auto-finalize': 'bool', '*auto-dismiss': 'bool' },
@@ -1638,6 +1638,7 @@ static const BlockJobDriver test_simple_job_driver = {
static int drop_intermediate_poll_update_filename(BdrvChild *child,
BlockDriverState *new_base,
const char *filename,
+ bool backing_file_format_no_protocol,
Error **errp)
{
/*
@@ -1749,7 +1750,7 @@ static void test_drop_intermediate_poll(void)
job->should_complete = true;
g_assert(!job_has_completed);
- ret = bdrv_drop_intermediate(chain[1], chain[0], NULL);
+ ret = bdrv_drop_intermediate(chain[1], chain[0], NULL, false);
aio_poll(qemu_get_aio_context(), false);
g_assert(ret == 0);
g_assert(job_has_completed);