diff --git a/sys/compat/linuxkpi/common/include/linux/seqlock.h b/sys/compat/linuxkpi/common/include/linux/seqlock.h
--- a/sys/compat/linuxkpi/common/include/linux/seqlock.h
+++ b/sys/compat/linuxkpi/common/include/linux/seqlock.h
@@ -36,6 +36,8 @@
 #include <sys/rwlock.h>
 #include <sys/seqc.h>
 
+#include <linux/compiler.h>
+
 struct lock_class_key;
 
 struct seqcount {
@@ -84,6 +86,13 @@
 	struct seqcount_mutex:	seqc_write_end				\
     )(&(s)->seqc)
 
+static inline void
+write_seqcount_invalidate(struct seqcount_mutex *seqcount)
+{
+	atomic_thread_fence_rel();
+	seqcount->seqc += 2;
+}
+
 #define	read_seqcount_begin(s)	seqc_read(&(s)->seqc)
 #define	raw_read_seqcount(s)	seqc_read_any(&(s)->seqc)
 
@@ -165,4 +174,10 @@
 #define	read_seqretry(seqlock, gen)	\
 	read_seqcount_retry(&(seqlock)->seql_count, gen)
 
+static inline unsigned
+seqprop_sequence(const seqcount_mutex_t *seqcount)
+{
+	return READ_ONCE(seqcount->seqc);
+}
+
 #endif	/* _LINUXKPI_LINUX_SEQLOCK_H__ */