Re: [PATCH 09/10] xfs: simplify extent lookup in xfs_can_free_eofblocks

["Darrick J. Wong" <djwong@kernel.org>]

On Sun, Jun 23, 2024 at 07:34:54AM +0200, Christoph Hellwig wrote:
> xfs_can_free_eofblocks just cares if there is an extent beyond EOF.
> Replace the call to xfs_bmapi_read with a xfs_iext_lookup_extent
> as we've already checked that extents are read in earlier.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

I guess that works :)
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
>  fs/xfs/xfs_bmap_util.c | 22 +++++++---------------
>  1 file changed, 7 insertions(+), 15 deletions(-)
> 
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index a4d9fbc21b8343..52863b784b023f 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -492,12 +492,12 @@ bool
>  xfs_can_free_eofblocks(
>  	struct xfs_inode	*ip)
>  {
> -	struct xfs_bmbt_irec	imap;
>  	struct xfs_mount	*mp = ip->i_mount;
> +	bool			found_blocks = false;
>  	xfs_fileoff_t		end_fsb;
>  	xfs_fileoff_t		last_fsb;
> -	int			nimaps = 1;
> -	int			error;
> +	struct xfs_bmbt_irec	imap;
> +	struct xfs_iext_cursor	icur;
>  
>  	/*
>  	 * Caller must either hold the exclusive io lock; or be inactivating
> @@ -544,21 +544,13 @@ xfs_can_free_eofblocks(
>  		return false;
>  
>  	/*
> -	 * Look up the mapping for the first block past EOF.  If we can't find
> -	 * it, there's nothing to free.
> +	 * Check if there is an post-EOF extent to free.
>  	 */
>  	xfs_ilock(ip, XFS_ILOCK_SHARED);
> -	error = xfs_bmapi_read(ip, end_fsb, last_fsb - end_fsb, &imap, &nimaps,
> -			0);
> +	if (xfs_iext_lookup_extent(ip, &ip->i_df, end_fsb, &icur, &imap))
> +		found_blocks = true;
>  	xfs_iunlock(ip, XFS_ILOCK_SHARED);
> -	if (error || nimaps == 0)
> -		return false;
> -
> -	/*
> -	 * If there's a real mapping there or there are delayed allocation
> -	 * reservations, then we have post-EOF blocks to try to free.
> -	 */
> -	return imap.br_startblock != HOLESTARTBLOCK || ip->i_delayed_blks;
> +	return found_blocks;
>  }
>  
>  /*
> -- 
> 2.43.0
> 
>