Re: [PATCH v2 1/7] splice: don't generate zero-len segement bvecs

From: Christoph Hellwig
Date: Mon Jan 04 2021 - 11:20:20 EST


On Sat, Jan 02, 2021 at 03:17:33PM +0000, Pavel Begunkov wrote:
> iter_file_splice_write() may spawn bvec segments with zero-length. In
> preparation for prohibiting them, filter out by hand at splice level.
>
> Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
> ---
> fs/splice.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/fs/splice.c b/fs/splice.c
> index 866d5c2367b2..7299330c3270 100644
> --- a/fs/splice.c
> +++ b/fs/splice.c
> @@ -644,7 +644,6 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
> ret = splice_from_pipe_next(pipe, &sd);
> if (ret <= 0)
> break;
> -

Spurious empty line removal..

> + if (!this_len)
> + continue;

Maybe throw in a comment on why we skip empty segments here?

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@xxxxxx>