Index: sys/sys/smr.h
===================================================================
--- sys/sys/smr.h
+++ sys/sys/smr.h
@@ -77,6 +77,70 @@
 #define	SMR_ASSERT_NOT_ENTERED(smr)					\
     KASSERT(!SMR_ENTERED(smr), ("In smr section."));
 
+#define SMR_ASSERT(ex, fn)						\
+    KASSERT((ex), (fn ": Assertion " #ex " failed at %s:%d", __FILE__, __LINE__))
+
+/* Type restricting pointer access to force smr accessors. */
+struct smr_ptr {
+	uintptr_t	__ptr;		/* Do not access directly */
+};
+typedef struct smr_ptr	smr_ptr_t;
+
+/*
+ * Read from an SMR protected pointer while in a section.
+ */
+#define	smr_entered_load(p, smr) ({					\
+	SMR_ASSERT(SMR_ENTERED((smr)), "smr_entered_load");		\
+	(void *)atomic_load_acq_ptr(&(p)->__ptr);			\
+})
+
+/*
+ * Read from an SMR protected pointer while serialized by an
+ * external mechanism.  'ex' should contain an assert that the
+ * external mechanism is held.  i.e. mtx_owned()
+ */
+#define	smr_serialized_load(p, ex) ({					\
+	SMR_ASSERT(ex, "smr_serialized_load");				\
+	(void *)atomic_load_ptr(&(p)->__ptr);				\
+})
+
+/*
+ * Store 'v' to an SMR protected pointer while serialized by an
+ * external mechanism.  'ex' should contain an assert that the
+ * external mechanism is held.  i.e. mtx_owned()
+ */
+#define	smr_serialized_store(p, v, ex) do {				\
+	SMR_ASSERT(ex, "smr_serialized_store");				\
+	atomic_store_rel_ptr(&(p)->__ptr, (uintptr_t)v);		\
+} while (0)
+
+/*
+ * swap 'v' with an SMR protected pointer and return the old value
+ * while serialized by an external mechanism.  'ex' should contain
+ * an assert that the external mechanism is provided.  i.e. mtx_owned()
+ */
+#define	smr_serialized_swap(p, v, ex) ({				\
+	SMR_ASSERT(ex, "smr_serialized_swap");				\
+	/* Release barrier guarantees contents are visible to reader */ \
+	atomic_thread_fence_rel();					\
+	(void *)atomic_swap_ptr(&(p)->__ptr, (uintptr_t)v);		\
+})
+
+/*
+ * Read from an SMR protected pointer when no serialization is required
+ * such as in the destructor callback or when the caller guarantees other
+ * mechanisms.
+ */
+#define	smr_unserialized_load(p, ex) ({					\
+	SMR_ASSERT(ex, "smr_unserialized_load");			\
+	(void *)atomic_load_ptr(&(p)->__ptr);				\
+})
+
+#define	smr_unserialized_store(p, v, ex) do {				\
+	SMR_ASSERT(ex, "smr_unserialized_store");			\
+	atomic_store_ptr(&(p)->__ptr, (uintptr_t)v);			\
+} while (0)
+
 /*
  * Return the current write sequence number.
  */