block: JSON filenames and relative backing files
When using a relative backing file name, qemu needs to know the
directory of the top image file. For JSON filenames, such a directory
cannot be easily determined (e.g. how do you determine the directory of
a qcow2 BDS directly on top of a quorum BDS?). Therefore, do not allow
relative filenames for the backing file of BDSs only having a JSON
filename.
Furthermore, BDS::exact_filename should be used whenever possible. If
BDS::filename is not equal to BDS::exact_filename, the former will
always be a JSON object.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block/qapi.c b/block/qapi.c
index fa68ba7..a6fd6f7 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -214,7 +214,12 @@
info->backing_filename = g_strdup(backing_filename);
info->has_backing_filename = true;
bdrv_get_full_backing_filename(bs, backing_filename2,
- sizeof(backing_filename2));
+ sizeof(backing_filename2), &err);
+ if (err) {
+ error_propagate(errp, err);
+ qapi_free_ImageInfo(info);
+ return;
+ }
if (strcmp(backing_filename, backing_filename2) != 0) {
info->full_backing_filename =
