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

[Filipe Manana <fdmanana@kernel.org>]

On Thu, Jan 31, 2019 at 4:31 PM Filipe Manana <fdmanana@kernel.org> wrote:
>
> 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.

Another ping. 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
> >