On Thu, May 3, 2018 at 6:26 PM, Goldwyn Rodrigues <rgoldwyn@xxxxxxx> wrote:
> From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
>
> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
> ---
> fs/overlayfs/copy_up.c | 2 +-
> fs/read_write.c | 10 ++++++----
> include/linux/fs.h | 2 ++
> 3 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
> index 8bede0742619..6634a85255ae 100644
> --- a/fs/overlayfs/copy_up.c
> +++ b/fs/overlayfs/copy_up.c
> @@ -175,7 +175,7 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len)
> break;
> }
>
> - bytes = do_splice_direct(old_file, &old_pos,
> + bytes = splice_with_holes(old_file, &old_pos,
> new_file, &new_pos,
> this_len, SPLICE_F_MOVE);
Add.. you can remove this comment above :)
/* FIXME: copy up sparse files efficiently */
For the record, when I added vfs_clone_file_range() above,
Dave Chinner has suggested to replace the entire block with
vfs_copy_file_range(), which would do all the fallbacks.
Since then, vfs_copy_file_range() gained "try to clone first".
There are still differences between the loop in this function and
the loop in vfs_copy_file_range(). Perhaps the differences could
be smoothed away, I did not check recently.
I am not asking that you do this as part of your work, simply
pointing out an opportunity.
Thanks,
Amir.
