diff --git a/sys/compat/linuxkpi/common/include/linux/bitops.h b/sys/compat/linuxkpi/common/include/linux/bitops.h
index 7ebb692ff172..a0d5be646c0b 100644
--- a/sys/compat/linuxkpi/common/include/linux/bitops.h
+++ b/sys/compat/linuxkpi/common/include/linux/bitops.h
@@ -35,6 +35,7 @@
 #include <sys/types.h>
 #include <sys/systm.h>
 #include <sys/errno.h>
+#include <sys/libkern.h>
 
 #define	BIT(nr)			(1UL << (nr))
 #define	BIT_ULL(nr)		(1ULL << (nr))
@@ -43,6 +44,7 @@
 #else
 #define	BITS_PER_LONG		32
 #endif
+
 #define	BITMAP_FIRST_WORD_MASK(start)	(~0UL << ((start) % BITS_PER_LONG))
 #define	BITMAP_LAST_WORD_MASK(n)	(~0UL >> (BITS_PER_LONG - (n)))
 #define	BITS_TO_LONGS(n)	howmany((n), BITS_PER_LONG)
@@ -51,6 +53,12 @@
 #define	GENMASK(h, l)		(((~0UL) >> (BITS_PER_LONG - (h) - 1)) & ((~0UL) << (l)))
 #define BITS_PER_BYTE           8
 
+#define	hweight8(x)	bitcount((uint8_t)(x))
+#define	hweight16(x)	bitcount16(x)
+#define	hweight32(x)	bitcount32(x)
+#define	hweight64(x)	bitcount64(x)
+#define	hweight_long(x)	bitcountl(x)
+
 static inline int
 __ffs(int mask)
 {
@@ -75,10 +83,15 @@ __flsl(long mask)
 	return (flsl(mask) - 1);
 }
 
+static inline int
+fls64(uint64_t mask)
+{
+	return (flsll(mask));
+}
+
 static inline uint32_t
 ror32(uint32_t word, unsigned int shift)
 {
-
 	return ((word >> shift) | (word << (32 - shift)));
 }
 
@@ -542,4 +555,12 @@ bitmap_equal(const unsigned long *pa,
 	return (1);
 }
 
+static inline uint64_t
+sign_extend64(uint64_t value, int index)
+{
+	uint8_t shift = 63 - index;
+
+	return ((int64_t)(value << shift) >> shift);
+}
+
 #endif	/* _LINUX_BITOPS_H_ */