Re: [RFC PATCH V2 10/12] fs/xfs: Fix truncate up

From: Darrick J. Wong
Date: Mon Jan 13 2020 - 17:30:11 EST


On Fri, Jan 10, 2020 at 11:29:40AM -0800, ira.weiny@xxxxxxxxx wrote:
> From: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> When zeroing the end of a file we must account for bytes contained in
> the final page which are past EOF.
>
> Extend the range passed to iomap_zero_range() to reach LLONG_MAX which
> will include all bytes of the final page.
>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> ---
> fs/xfs/xfs_iops.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index a2f2604c3187..a34b04e8ac9c 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -910,7 +910,7 @@ xfs_setattr_size(
> */
> if (newsize > oldsize) {
> trace_xfs_zero_eof(ip, oldsize, newsize - oldsize);
> - error = iomap_zero_range(inode, oldsize, newsize - oldsize,
> + error = iomap_zero_range(inode, oldsize, LLONG_MAX - oldsize,

Huh? Won't this cause the file size to be set to LLONG_MAX?

--D

> &did_zeroing, &xfs_buffered_write_iomap_ops);
> } else {
> error = iomap_truncate_page(inode, newsize, &did_zeroing,
> --
> 2.21.0
>