Please see patches for rationale. Libvirt patches using this new flag will be posted soon-ish (after cleanup).
Peter Krempa (2): block: commit: Allow users to request only format driver names in backing file format block: stream: Allow users to request only format driver names in backing file format block.c | 37 +++++++++++++++++++++----- block/commit.c | 6 ++++- block/monitor/block-hmp-cmds.c | 2 +- block/stream.c | 10 ++++++- blockdev.c | 13 +++++++++ include/block/block-global-state.h | 3 ++- include/block/block_int-common.h | 4 ++- include/block/block_int-global-state.h | 6 +++++ qapi/block-core.json | 22 +++++++++++++-- tests/unit/test-bdrv-drain.c | 3 ++- 10 files changed, 91 insertions(+), 15 deletions(-) -- 2.43.0