[PATCH] xfs: fix directory readahead offset off-by-one

[Christoph Hellwig]

On Tue, May 06, 2014 at 01:42:08PM +1000, Dave Chinner wrote:
> Fix the warning by ensuring that the readahead offset is correctly
> incremented.
> 
> Signed-off-by: Dave Chinner <dchinner at redhat.com>
> ---
>  fs/xfs/xfs_dir2_readdir.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/xfs/xfs_dir2_readdir.c b/fs/xfs/xfs_dir2_readdir.c
> index 50b72f7..fe2db98 100644
> --- a/fs/xfs/xfs_dir2_readdir.c
> +++ b/fs/xfs/xfs_dir2_readdir.c
> @@ -456,7 +456,7 @@ xfs_dir2_leaf_readbuf(
>  		/*
>  		 * Advance offset through the mapping table.
>  		 */
> -		for (j = 0; j < mp->m_dirblkfsbs; j++) {
> +		for (j = 0; j < mp->m_dirblkfsbs; ) {
>  			/*
>  			 * The rest of this extent but not more than a dir
>  			 * block.

This looks correct, but it would seem a little more idiomatic to write
this as:

		for (j = 0; j < mp->m_dirblkfsbs; j += length) {

and remove the j increment from the body.