diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 9f47ec2b..a7231b8b 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -25,6 +25,17 @@ int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
 #define small_const_nbits(nbits) \
 	(__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
 
+static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
+				     unsigned int bits)
+{
+	unsigned int k, lim = bits/BITS_PER_LONG;
+	for (k = 0; k < lim; ++k)
+		dst[k] = ~src[k];
+
+	if (bits % BITS_PER_LONG)
+		dst[k] = ~src[k];
+}
+
 static inline void bitmap_zero(unsigned long *dst, int nbits)
 {
 	memset(dst, 0, BITS_TO_LONGS(nbits) * sizeof(unsigned long));
diff --git a/include/linux/bug.h b/include/linux/bug.h
index aa5776c7..89cdd30d 100644
--- a/include/linux/bug.h
+++ b/include/linux/bug.h
@@ -15,7 +15,7 @@
 #define BUG_ON(cond)		assert(!(cond))
 
 #define WARN_ON_ONCE(cond)	assert(!(cond))
-#define WARN_ONCE(cond, msg)	assert(!(cond))
+#define WARN_ONCE(cond, msg)	({ bool _r = (cond); if (_r) assert(0); _r; })
 
 #define __WARN()		assert(0)
 #define __WARN_printf(arg...)	assert(0)
diff --git a/include/linux/closure.h b/include/linux/closure.h
index 33280d30..a9de6d93 100644
--- a/include/linux/closure.h
+++ b/include/linux/closure.h
@@ -382,4 +382,26 @@ static inline void closure_call(struct closure *cl, closure_fn fn,
 	continue_at_nobarrier(cl, fn, wq);
 }
 
+#define __closure_wait_event(waitlist, _cond)				\
+do {									\
+	struct closure cl;						\
+									\
+	closure_init_stack(&cl);					\
+									\
+	while (1) {							\
+		closure_wait(waitlist, &cl);				\
+		if (_cond)						\
+			break;						\
+		closure_sync(&cl);					\
+	}								\
+	closure_wake_up(waitlist);					\
+	closure_sync(&cl);						\
+} while (0)
+
+#define closure_wait_event(waitlist, _cond)				\
+do {									\
+	if (!(_cond))							\
+		__closure_wait_event(waitlist, _cond);			\
+} while (0)
+
 #endif /* _LINUX_CLOSURE_H */
diff --git a/include/linux/random.h b/include/linux/random.h
index 95a15d05..6d63e045 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -37,4 +37,12 @@ static inline int get_random_int(void)
 	return v;
 }
 
+static inline long get_random_long(void)
+{
+	long v;
+
+	get_random_bytes(&v, sizeof(v));
+	return v;
+}
+
 #endif /* _LINUX_RANDOM_H */