block/raw-posix: Fix disk corruption in try_fiemap
Using fiemap without FIEMAP_FLAG_SYNC is a known corrupter.
Add the FIEMAP_FLAG_SYNC flag to the FS_IOC_FIEMAP ioctl. This has
the downside of significantly reducing performance.
Reported-By: Michael Steffens <michael_steffens@posteo.de> Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Markus Armbruster <armbru@redhat.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Max Reitz <mreitz@redhat.com> Cc: Pádraig Brady <pbrady@redhat.com> Cc: Eric Blake <eblake@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>