On 18/08/2015 19:54, Wen Congyang wrote: > We will copy data in before_write_notifier to do backup. > It is a nested I/O request, so we cannot do copy-on-read.
Can you explain why? What is the bug that this is fixing? Paolo > Signed-off-by: Wen Congyang <we...@cn.fujitsu.com>