116 		 * (upper fsid is 0). The lowest xinobit is reserved for mapping  in ovl_map_dev_ino()
202 			 * upper files, so we cannot use the lower origin st_ino  in ovl_getattr()
212 			 * upper hardlink is not broken and that a redirected  in ovl_getattr()
239 			 * no origin on upper, we can end up here.  in ovl_getattr()
266 	 * Return the overlay inode nlinks for indexed upper inodes.  in ovl_getattr()
267 	 * Overlay inode nlink counts the union of the upper hardlinks  in ovl_getattr()
268 	 * and non-covered lower hardlinks. It does not include the upper  in ovl_getattr()
555  * upper fs:
617 	 * To avoid ino collision with legitimate xino values from upper  in ovl_map_ino()
682  * With inodes index enabled, an overlay inode nlink counts the union of upper
684  * upper inode, the following nlink modifying operations can happen:
687  * 2. Upper hardlink created, unlinked or renamed over
691  * operation succeeds or fails, but the upper inode nlink may change.
695  * For the second, upper hardlink case, the union nlink should be incremented
697  * upper inode. Therefore, before link/unlink/rename, we store the union nlink
698  * value relative to the upper inode nlink in the index inode.
702  * upper inode where the nlink xattr can be stored before the copied up upper
710  * nlink relative to the upper inode - "U[+-]NUM"
809 	 * checks, so NULL lower/upper in dentry must match NULL lower/upper in  in ovl_verify_inode()
811 	 * 'unknown' lower/upper.  in ovl_verify_inode()
814 		/* Real lower dir moved to upper layer under us? */  in ovl_verify_inode()
911 static bool ovl_hash_bylower(struct super_block *sb, struct dentry *upper,  in ovl_hash_bylower()  argument
916 	/* No, if pure upper */  in ovl_hash_bylower()
929 	if ((upper || !ovl_indexdir(sb)) &&  in ovl_hash_bylower()
933 	/* No, if non-indexed upper with NFS export */  in ovl_hash_bylower()
934 	if (sb->s_export_op && upper)  in ovl_hash_bylower()
970 	 * Copy up origin (lower) may exist for non-indexed upper, but we must  in ovl_get_inode()