block: Add 'base-node' parameter to the 'block-stream' command
The way to specify the node from which to copy data in the
block-stream operation is by using the 'base' parameter. This
parameter however takes a file name, not a node name.
Since we want to be able to perform this operation using only node
names, this patch adds a new 'base-node' parameter.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/blockdev.c b/blockdev.c
index b5d4d69..ded1326 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2932,6 +2932,7 @@
void qmp_block_stream(bool has_job_id, const char *job_id, const char *device,
bool has_base, const char *base,
+ bool has_base_node, const char *base_node,
bool has_backing_file, const char *backing_file,
bool has_speed, int64_t speed,
bool has_on_error, BlockdevOnError on_error,
@@ -2955,6 +2956,12 @@
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
+ if (has_base && has_base_node) {
+ error_setg(errp, "'base' and 'base-node' cannot be specified "
+ "at the same time");
+ goto out;
+ }
+
if (has_base) {
base_bs = bdrv_find_backing_image(bs, base);
if (base_bs == NULL) {
@@ -2965,6 +2972,20 @@
base_name = base;
}
+ if (has_base_node) {
+ base_bs = bdrv_lookup_bs(NULL, base_node, errp);
+ if (!base_bs) {
+ goto out;
+ }
+ if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
+ error_setg(errp, "Node '%s' is not a backing image of '%s'",
+ base_node, device);
+ goto out;
+ }
+ assert(bdrv_get_aio_context(base_bs) == aio_context);
+ base_name = base_bs->filename;
+ }
+
/* Check for op blockers in the whole chain between bs and base */
for (iter = bs; iter && iter != base_bs; iter = backing_bs(iter)) {
if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
