On Mon, Feb 9, 2015 at 10:54 PM, Stefan Hajnoczi <stefa...@gmail.com> wrote:
> On Sun, Feb 08, 2015 at 08:39:52PM +0800, Xiaodong Gong wrote: > > When open the vpc snapshot based FIXED format, its backing file, > > this FIXED vpc image, could be probed as a raw image, because that > > the find_image_format just checkout the first sector. > > > > Add a re-probe for the last sector to FIXED base vpc image,when get > > a NULL or raw driver in first sector probe. > > > > Signed-off-by: Xiaodong Gong <gongxiaodo...@huawei.com> > > --- > > block.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++------- > > 1 file changed, 48 insertions(+), 7 deletions(-) > > This approach is likely to cause issues because it makes no distiction > between headers and footers. Most image formats only have a header and > would now be misdetected if a raw image had a header in its last sector. > > When a vpc image has a backing file, does it make sense to set the > bs->backing_format to "vpc"? That way we'll try to open the backing > file as a vpc image without probing. > > Stefan > It works, but this probing of format sounds good . Giving a argument of bs to bdrv_probe and each of funtion of probe get it's own checking method is better, but the foot-print of patch is longer.
