Re: [PATCH] Fix check for block zero access in xfs_write_iomap_allocate

[Lachlan McIlroy <lachlan@sgi.com>]

Looks good.

David Chinner wrote:
> Fix check for block zero access in xfs_write_iomap_allocate
> 
> The check for block zero access should be done on non-realtime
> inodes. Fix the logic error in xfs_write_iomap_allocate(), and
> simplify the logic on all checks for block zero access.
> 
> Signed-off-by: Dave Chinner <dgc@sgi.com>
> ---
>  fs/xfs/xfs_iomap.c |   13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
> 
> Index: 2.6.x-xfs-new/fs/xfs/xfs_iomap.c
> ===================================================================
> --- 2.6.x-xfs-new.orig/fs/xfs/xfs_iomap.c	2008-04-22 11:54:54.000000000 +1000
> +++ 2.6.x-xfs-new/fs/xfs/xfs_iomap.c	2008-04-22 20:45:53.469961429 +1000
> @@ -523,8 +523,7 @@ xfs_iomap_write_direct(
>  		goto error_out;
>  	}
>  
> -	if (unlikely(!imap.br_startblock &&
> -		     !(XFS_IS_REALTIME_INODE(ip)))) {
> +	if (!(imap.br_startblock || XFS_IS_REALTIME_INODE(ip))) {
>  		error = xfs_cmn_err_fsblock_zero(ip, &imap);
>  		goto error_out;
>  	}
> @@ -686,8 +685,7 @@ retry:
>  		goto retry;
>  	}
>  
> -	if (unlikely(!imap[0].br_startblock &&
> -		     !(XFS_IS_REALTIME_INODE(ip))))
> +	if (!(imap[0].br_startblock || XFS_IS_REALTIME_INODE(ip)))
>  		return xfs_cmn_err_fsblock_zero(ip, &imap[0]);
>  
>  	*ret_imap = imap[0];
> @@ -838,9 +836,9 @@ xfs_iomap_write_allocate(
>  		 * See if we were able to allocate an extent that
>  		 * covers at least part of the callers request
>  		 */
> -		if (unlikely(!imap.br_startblock &&
> -			     XFS_IS_REALTIME_INODE(ip)))
> +		if (!(imap.br_startblock || XFS_IS_REALTIME_INODE(ip)))
>  			return xfs_cmn_err_fsblock_zero(ip, &imap);
> +
>  		if ((offset_fsb >= imap.br_startoff) &&
>  		    (offset_fsb < (imap.br_startoff +
>  				   imap.br_blockcount))) {
> @@ -934,8 +932,7 @@ xfs_iomap_write_unwritten(
>  		if (error)
>  			return XFS_ERROR(error);
>  
> -		if (unlikely(!imap.br_startblock &&
> -			     !(XFS_IS_REALTIME_INODE(ip))))
> +		if (!(imap.br_startblock || XFS_IS_REALTIME_INODE(ip)))
>  			return xfs_cmn_err_fsblock_zero(ip, &imap);
>  
>  		if ((numblks_fsb = imap.br_blockcount) == 0) {
> 
> 
>