static void inode_free_security(struct inode *inode)
{
	struct inode_security_struct *isec = selinux_inode(inode);
	struct superblock_security_struct *sbsec;

	if (!isec)
		return;
	sbsec = selinux_superblock(inode->i_sb);
	/*
	 * As not all inode security structures are in a list, we check for
	 * empty list outside of the lock to make sure that we won't waste
	 * time taking a lock doing nothing.
	 *
	 * The list_del_init() function can be safely called more than once.
	 * It should not be possible for this function to be called with
	 * concurrent list_add(), but for better safety against future changes
	 * in the code, we use list_empty_careful() here.
	 */
	if (!list_empty_careful(&isec->list)) {
		spin_lock(&sbsec->isec_lock);
		list_del_init(&isec->list);
		spin_unlock(&sbsec->isec_lock);
	}
}
static void inode_free_security(struct inode *inode)
{
	struct inode_security_struct *isec = selinux_inode(inode);
	struct superblock_security_struct *sbsec;

	if (!isec)
		return;
	sbsec = selinux_superblock(inode->i_sb);
	 
	if (!list_empty_careful(&isec->list)) {
		spin_lock(&sbsec->isec_lock);
		list_del_init(&isec->list);
		spin_unlock(&sbsec->isec_lock);
	}
}