vfs: vfs_clone_file_prep_inodes should return EINVAL for a clone from beyond EOF

vfs_clone_file_prep_inodes cannot return 0 if it is asked to remap from
a zero byte file because that's what btrfs does.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/read_write.c b/fs/read_write.c
index 8a2737f..260797b 100644 (file)
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1740,10 +1740,7 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
        if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
                return -EINVAL;
 
-       /* Are we going all the way to the end? */
        isize = i_size_read(inode_in);
-       if (isize == 0)
-               return 0;
 
        /* Zero length dedupe exits immediately; reflink goes to EOF. */
        if (*len == 0) {