Index: sys/cam/cam_ccb.h
===================================================================
--- sys/cam/cam_ccb.h
+++ sys/cam/cam_ccb.h
@@ -247,6 +247,12 @@
 	XPT_REPROBE_LUN		= 0x38 | XPT_FC_QUEUED | XPT_FC_USER_CCB,
 				/* Query device capacity and notify GEOM */
 
+/* Generic SIM: 0x40->0x4f */
+	XPT_KV_GET		= 0x40,
+				/* Get the Value for the passed in Key */
+	XPT_KV_SET		= 0x41,
+				/* Set the value based on the key */
+
 /* Vendor Unique codes: 0x80->0x8F */
 	XPT_VUNIQUE		= 0x80
 } xpt_opcode;
@@ -1294,6 +1300,24 @@
 	void *async_arg_ptr;
 };
 
+/*
+ * CCB for key value pairs
+ */
+struct ccb_kv {
+	struct	ccb_hdr			ccb_h;
+#define	CCB_KV_KEY_LEN		64
+#define	CCB_KV_VAL_LEN		128
+	char				key[CCB_KV_KEY_LEN];
+	uint32_t			val_len;
+	union {
+		void			*ptr;		/* In kernel only */
+		uintptr_t		num;
+		char			value[CCB_KV_VAL_LEN];
+	} u;
+};
+#define	CCB_KV_DEVICE_T			"device_t"
+#define	CCB_KV_NUMA_DOMAIN		"numa_domain"
+
 /*
  * Union of all CCB types for kernel space allocation.  This union should
  * never be used for manipulating CCBs - its only use is for the allocation
@@ -1336,6 +1360,7 @@
 	struct	ccb_async		casync;
 	struct	ccb_nvmeio		nvmeio;
 	struct	ccb_mmcio		mmcio;
+	struct	ccb_kv			kv;
 };
 
 #define CCB_CLEAR_ALL_EXCEPT_HDR(ccbp)			\
Index: sys/cam/cam_xpt.h
===================================================================
--- sys/cam/cam_xpt.h
+++ sys/cam/cam_xpt.h
@@ -163,6 +163,43 @@
 	xpt_action((union ccb *)cpi);
 }
 
+/*
+ * Get the @key associated with the @path using the @ckv CCB to ask the
+ * SIM.
+ */
+static inline void
+xpt_kv_get(struct ccb_kv *ckv, struct cam_path *path, const char *key)
+{
+
+	bzero(ckv, sizeof(*ckv));
+	xpt_setup_ccb(&ckv->ccb_h, path, CAM_PRIORITY_NORMAL);
+	ckv->ccb_h.func_code = XPT_KV_GET;
+	strlcpy(ckv->key, key, sizeof(ckv->key));
+	xpt_action((union ccb *)ckv);
+}
+
+/*
+ * Set the @key associated with the @path using the @ckv CCB to ask the
+ * SIM.
+ */
+static inline void
+xpt_kv_set(struct ccb_kv *ckv, struct cam_path *path, const char *key,
+    void *value, size_t len)
+{
+
+	bzero(ckv, sizeof(*ckv));
+	xpt_setup_ccb(&ckv->ccb_h, path, CAM_PRIORITY_NORMAL);
+	ckv->ccb_h.func_code = XPT_KV_SET;
+	if (len > sizeof(ckv->u)) {
+		/* Not queued, so just set status and return */
+		ckv->ccb_h.status = CAM_REQ_ABORTED | CAM_REQ_TOO_BIG;
+		return;
+	}
+	strlcpy(ckv->key, key, sizeof(ckv->key));
+	memcpy(&ckv->u, value, len);
+	xpt_action((union ccb *)ckv);
+}
+
 #endif /* _KERNEL */
 
 #endif /* _CAM_CAM_XPT_H */