On Wed, Aug 26, 2015 at 9:11 PM, Christoph Hellwig [off-list ref] wrote:

On Wed, Aug 26, 2015 at 04:16:41PM +0800, Peng Tao wrote:

quoted

2. vfs_file_clone_range() does not expect file systems to do data copy, and thus
no rw_verify_area() required.

While there is no physical copy involved, the data logically is copied from
file A to file B.  So we still need all the checks from rw_verify_area.

I see. Will add the checks.

Cheers,
Tao