Re: [PATCH 3/8] iomap: Move lockdep_assert_held() to iomap_dio_rw() calls

Darrick J. Wong
2019-12-18T02:04:51Z

On Fri, Dec 13, 2019 at 01:57:45PM -0600, Goldwyn Rodrigues wrote:
> From: Goldwyn Rodrigues <rgoldwyn@suse.com>
>
> Filesystems such as btrfs can perform direct I/O without holding the
> inode->i_rwsem in some of the cases like writing within i_size.
> So, remove the check for lockdep_assert_held() in iomap_dio_rw()
>
> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>

/me wishes there was a way for iomap to verify that the fs has indeed
taken /some/ measure to ensure correct concurrent operations, but that's
probably just asking for liar functions. :)

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

--D

> ---
> fs/iomap/direct-io.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
> index 1a3bf3bd86fb..41c1e7c20a1f 100644
> --- a/fs/iomap/direct-io.c
> +++ b/fs/iomap/direct-io.c
> @@ -415,8 +415,6 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
> struct blk_plug plug;
> struct iomap_dio *dio;
>
> - lockdep_assert_held(&inode->i_rwsem);
> -
> if (!count)
> return 0;
>
> --
> 2.16.4
>