xfs: fix the same_inode check in xfs_file_share_range

The VFS i_ino is an unsigned long, while XFS inode numbers are 64-bit
wide, so checking i_ino for equality could lead to rate false positives
on 32-bit architectures.  Just compare the inode pointers themselves
to be safe.

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

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 194f8f3..d5b835e 100644 (file)
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -965,7 +965,7 @@ xfs_file_share_range(
            IS_SWAPFILE(inode_out))
                return -ETXTBSY;
 
-       same_inode = (inode_in->i_ino == inode_out->i_ino);
+       same_inode = (inode_in == inode_out);
 
        /* Don't reflink dirs, pipes, sockets... */
        if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))