Re: [PATCH 4/4] Btrfs: remove no longer needed range length checks for deduplication

[Filipe Manana <fdmanana@kernel.org>]

On Wed, Dec 12, 2018 at 6:07 PM <fdmanana@kernel.org> wrote:
>
> From: Filipe Manana <fdmanana@suse.com>
>
> Comparing the content of the pages in the range to deduplicate is now done
> by the generic helper generic_remap_file_range_prep(), which takes care of
> ensuring we do not compare/deduplicate undefined data beyond a file's eof
> (range from eof to the next block boundary). So remove these checks which
> are now redundant.
>
> Signed-off-by: Filipe Manana <fdmanana@suse.com>

Any reason why this was not yet picked?
Thanks.

> ---
>  fs/btrfs/ioctl.c | 19 ++-----------------
>  1 file changed, 2 insertions(+), 17 deletions(-)
>
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index 4e9efc93340e..3a27efa2b955 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -3206,31 +3206,16 @@ static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
>         inode_lock_nested(inode2, I_MUTEX_CHILD);
>  }
>
> -static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 olen,
> +static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 len,
>                                    struct inode *dst, u64 dst_loff)
>  {
> -       u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
>         int ret;
> -       u64 len = olen;
> -
> -       if (loff + len == src->i_size)
> -               len = ALIGN(src->i_size, bs) - loff;
> -       /*
> -        * For same inode case we don't want our length pushed out past i_size
> -        * as comparing that data range makes no sense.
> -        *
> -        * This effectively means we require aligned extents for the single
> -        * inode case, whereas the other cases allow an unaligned length so long
> -        * as it ends at i_size.
> -        */
> -       if (dst == src && len != olen)
> -               return -EINVAL;
>
>         /*
>          * Lock destination range to serialize with concurrent readpages().
>          */
>         lock_extent(&BTRFS_I(dst)->io_tree, dst_loff, dst_loff + len - 1);
> -       ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
> +       ret = btrfs_clone(src, dst, loff, len, len, dst_loff, 1);
>         unlock_extent(&BTRFS_I(dst)->io_tree, dst_loff, dst_loff + len - 1);
>
>         return ret;
> --
> 2.11.0
>