diff --git a/include/linux/time.h b/include/linux/time.h
index b306178..93277a0 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -4,8 +4,11 @@
 #include <linux/types.h>
 
 #ifdef __KERNEL__
+# include <linux/bitops.h>
 # include <linux/cache.h>
+# include <linux/posix_types.h>
 # include <linux/seqlock.h>
+# include <linux/string.h>
 # include <linux/math64.h>
 #endif
 
@@ -256,6 +259,27 @@
 	a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
 	a->tv_nsec = ns;
 }
+
+static inline void __FD_SET(unsigned long __fd, __kernel_fd_set *__fdsetp)
+{
+	__set_bit(__fd, __fdsetp->fds_bits);
+}
+
+static inline void __FD_CLR(unsigned long __fd, __kernel_fd_set *__fdsetp)
+{
+	__clear_bit(__fd, __fdsetp->fds_bits);
+}
+
+static inline int __FD_ISSET(unsigned long __fd, const __kernel_fd_set *__fdsetp)
+{
+	return test_bit(__fd, __fdsetp->fds_bits);
+}
+
+static inline void __FD_ZERO(__kernel_fd_set *__fdsetp)
+{
+	memset(__fdsetp->fds_bits, 0, sizeof __fdsetp->fds_bits);
+}
+
 #endif /* __KERNEL__ */
 
 #define NFDBITS			__NFDBITS