On 2015-02-11 at 22:07, Wen Congyang wrote:
Signed-off-by: Wen Congyang <[email protected]> Signed-off-by: zhanghailiang <[email protected]> Signed-off-by: Gonglei <[email protected]> --- block.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
I don't think this is a good idea. With this patch, every time you open a COW file (with a backing file) R/W, the backing file will be writable. I'd rather like a way to explicitly overwrite the R/W mode of the backing file; but by default, in my opinion, it should stay read-only.
Max
diff --git a/block.c b/block.c index 067c44b..96cf973 100644 --- a/block.c +++ b/block.c @@ -856,8 +856,8 @@ static int bdrv_inherited_flags(int flags) */ static int bdrv_backing_flags(int flags) { - /* backing files always opened read-only */ - flags &= ~(BDRV_O_RDWR | BDRV_O_COPY_ON_READ); + /* backing files are opened read-write for block replication */ + flags &= ~BDRV_O_COPY_ON_READ;/* snapshot=on is handled on the top layer */flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_TEMPORARY);
