[PATCH] xfs_io: Prevent devide by zero from {pread, pwrite}_random

[Christoph Hellwig]

On Thu, Feb 25, 2016 at 07:20:53PM +0400, Dmitry Monakhov wrote:
> 
> Math is wrong if range requested is less or equals to block size
> 
> xfs_io -c 'pwrite -b 4k 8k 4k -R' \
>        -c 'pread -b 4k  4k 4k -R' -f file
> 
> Signed-off-by: Dmitry Monakhov <dmonakhov at openvz.org>

Looks fine,

Reviewed-by: Christoph Hellwig <hch at lst.de>

Are we going to see a new testcase that relies on this soon? :)