Re: [PATCH 5/7] xfs: extent shifting doesn't fully invalidate page cache

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Tue, Nov 20, 2018 at 08:04:57AM +1100, Dave Chinner wrote:
> From: Dave Chinner <dchinner@redhat.com>
> 
> The extent shifting code uses a flush and invalidate mechainsm prior
> to shifting extents around. This is similar to what
> xfs_free_file_space() does, but it doesn't take into account things
> like page cache vs block size differences, and it will fail if there
> is a page that it currently busy.
> 
> xfs_flush_unmap_range() handles all of these cases, so just convert
> xfs_prepare_shift() to us that mechanism rather than having it's own
> special sauce.
> 
> Signed-off-by: Dave Chinner <dchinner@redhat.com>

Looks ok,
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
>  fs/xfs/xfs_bmap_util.c | 8 +-------
>  1 file changed, 1 insertion(+), 7 deletions(-)
> 
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index 5d263dfdb3bc..167ff4297e5c 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -1195,13 +1195,7 @@ xfs_prepare_shift(
>  	 * Writeback and invalidate cache for the remainder of the file as we're
>  	 * about to shift down every extent from offset to EOF.
>  	 */
> -	error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping, offset, -1);
> -	if (error)
> -		return error;
> -	error = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
> -					offset >> PAGE_SHIFT, -1);
> -	if (error)
> -		return error;
> +	error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip));
>  
>  	/*
>  	 * Clean out anything hanging around in the cow fork now that
> -- 
> 2.19.1
>