We haven't used this since commit 
9be3395bcd4a ("Btrfs: use a btrfs
bioset instead of abusing bio internals").
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
        u64 logical_offset;
        u64 disk_bytenr;
        u64 bytes;
-       void *private;
 
        /* number of bios pending for this dio */
        atomic_t pending_bios;
 
        bio->bi_private = dip;
        btrfs_io_bio(bio)->logical = file_offset;
 
-       dip->private = dio_bio->bi_private;
        dip->inode = inode;
        dip->logical_offset = file_offset;
        dip->bytes = dio_bio->bi_iter.bi_size;