*/
extern int __must_check down_interruptible(struct semaphore *sem);
+/*
+ * As down_interruptible(), except the sleep may only be interrupted by
+ * signals which are fatal to this process.
+ */
+extern int __must_check down_killable(struct semaphore *sem);
+
/*
* As down(), except this function will not sleep. It will return 0 if it
* acquired the semaphore and 1 if the semaphore was contended. This