[PATCH 0/2] Add FALLOC_FL_ZERO_RANGE to fallocate

[Dave Chinner]

On Tue, Jun 12, 2012 at 05:36:02PM +0200, Paolo Bonzini wrote:
> This patch adds the FALLOC_FL_ZERO_RANGE operation mode to fallocate,
> resembling the similar XFS ioctl.  The new mode can be used with
> or without FALLOC_FL_KEEP_SIZE, but of course not together with
> FALLOC_FL_PUNCH_HOLE.

!FALLOC_FL_KEEP_SIZE makes no sense for this operation. It is for
zeroing an existing section of a file while retaining the allocated
space, not for extending or truncating the file. It's the same
reason that FALLOC_FL_PUNCH_HOLE must have FALLOC_FL_KEEP_SIZE set.

Also, a minor nit, but you should credit where this code has
originated from in the commit messages, and describe the use case
for requiring it. i.e. based on:

http://permalink.gmane.org/gmane.linux.file-systems/62449

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com