Index: sys/kern/kern_conf.c
===================================================================
--- sys/kern/kern_conf.c
+++ sys/kern/kern_conf.c
@@ -56,9 +56,6 @@
 static int destroy_dev_sched_cbl(struct cdev *dev,
     void (*cb)(void *), void *arg);
 static void destroy_dev_tq(void *ctx, int pending);
-static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw,
-    int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
-    va_list ap);
 
 static struct cdev_priv_list cdevp_free_list =
     TAILQ_HEAD_INITIALIZER(cdevp_free_list);
@@ -566,7 +563,8 @@
 }
 
 static struct cdev *
-newdev(struct cdevsw *csw, int unit, struct cdev *si)
+newdev(struct cdevsw *csw, int unit, struct cdev *si,
+    void *drv1, void *drv2)
 {
 	struct cdev *si2;
 
@@ -581,6 +579,8 @@
 		}
 	}
 	si->si_drv0 = unit;
+	si->si_drv1 = drv1;
+	si->si_drv2 = drv2;
 	si->si_devsw = csw;
 	LIST_INSERT_HEAD(&csw->d_devs, si, si_list);
 	return (si);
@@ -738,32 +738,41 @@
 }
 
 static int
-make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit,
-    struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
-    va_list ap)
+make_dev_argv(struct cdev **ppdev, const struct make_dev_args *pargs,
+    const char *fmt, va_list ap)
 {
-	struct cdev *dev, *dev_new;
+	struct cdev *dev_new;
+	struct cdev *dev;
 	int res;
 
-	KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
-	    ("make_dev_credv: both WAITOK and NOWAIT specified"));
-	dev_new = devfs_alloc(flags);
+	KASSERT(pargs != NULL, ("make_dev_argv: pargs is NULL"));
+	KASSERT((pargs->flags & MAKEDEV_WAITOK) == 0 ||
+	    (pargs->flags & MAKEDEV_NOWAIT) == 0,
+	    ("make_dev_argv: both WAITOK and NOWAIT specified"));
+	KASSERT(pargs->si_devsw != NULL,
+	    ("make_dev_argv: pargs->si_devsw is NULL"));
+	KASSERT(pargs->version == MAKE_DEV_ARGS_VERSION,
+	    ("make_dev_argv: Invalid version %d != %d",
+	    pargs->version, MAKE_DEV_ARGS_VERSION));
+
+	dev_new = devfs_alloc(pargs->flags);
 	if (dev_new == NULL)
 		return (ENOMEM);
 	dev_lock();
-	res = prep_cdevsw(devsw, flags);
+	res = prep_cdevsw(pargs->si_devsw, pargs->flags);
 	if (res != 0) {
 		dev_unlock();
 		devfs_free(dev_new);
 		return (res);
 	}
-	dev = newdev(devsw, unit, dev_new);
+	dev = newdev(pargs->si_devsw, pargs->si_drv0, dev_new,
+	    pargs->si_drv1, pargs->si_drv2);
 	if ((dev->si_flags & SI_NAMED) == 0) {
 		res = prep_devname(dev, fmt, ap);
 		if (res != 0) {
-			if ((flags & MAKEDEV_CHECKNAME) == 0) {
+			if ((pargs->flags & MAKEDEV_CHECKNAME) == 0) {
 				panic(
-			"make_dev_credv: bad si_name (error=%d, si_name=%s)",
+			"make_dev_argv: bad si_name (error=%d, si_name=%s)",
 				    res, dev->si_name);
 			}
 			if (dev == dev_new) {
@@ -775,9 +784,9 @@
 			return (res);
 		}
 	}
-	if (flags & MAKEDEV_REF)
+	if (pargs->flags & MAKEDEV_REF)
 		dev_refl(dev);
-	if (flags & MAKEDEV_ETERNAL)
+	if (pargs->flags & MAKEDEV_ETERNAL)
 		dev->si_flags |= SI_ETERNAL;
 	if (dev->si_flags & SI_CHEAPCLONE &&
 	    dev->si_flags & SI_NAMED) {
@@ -787,26 +796,26 @@
 		 * XXX: still ??
 		 */
 		dev_unlock_and_free();
-		*dres = dev;
+		*ppdev = dev;
 		return (0);
 	}
 	KASSERT(!(dev->si_flags & SI_NAMED),
 	    ("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
-	    devsw->d_name, dev2unit(dev), devtoname(dev)));
+	    pargs->si_devsw->d_name, dev2unit(dev), devtoname(dev)));
 	dev->si_flags |= SI_NAMED;
-	if (cr != NULL)
-		dev->si_cred = crhold(cr);
-	dev->si_uid = uid;
-	dev->si_gid = gid;
-	dev->si_mode = mode;
+	if (pargs->si_cred != NULL)
+		dev->si_cred = crhold(pargs->si_cred);
+	dev->si_uid = pargs->si_uid;
+	dev->si_gid = pargs->si_gid;
+	dev->si_mode = pargs->si_mode;
 
 	devfs_create(dev);
 	clean_unrhdrl(devfs_inos);
 	dev_unlock_and_free();
 
-	notify_create(dev, flags);
+	notify_create(dev, pargs->flags);
 
-	*dres = dev;
+	*ppdev = dev;
 	return (0);
 }
 
@@ -814,33 +823,66 @@
 make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
     const char *fmt, ...)
 {
+	struct make_dev_args args = {
+		.version = MAKE_DEV_ARGS_VERSION,
+		.si_drv0 = unit,
+		.si_uid = uid,
+		.si_gid = gid,
+		.si_mode = mode,
+		.si_devsw = devsw,
+	};
 	struct cdev *dev;
 	va_list ap;
 	int res;
 
 	va_start(ap, fmt);
-	res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt,
-	    ap);
+	res = make_dev_argv(&dev, &args, fmt, ap);
 	va_end(ap);
 	KASSERT(res == 0 && dev != NULL,
-	    ("make_dev: failed make_dev_credv (error=%d)", res));
+	    ("make_dev: failed make_dev_argv (error=%d)", res));
 	return (dev);
 }
 
+int
+make_dev_args(struct cdev **ppdev, const struct make_dev_args *pargs,
+    const char *fmt, ...)
+{
+	va_list ap;
+	int res;
+
+	va_start(ap, fmt);
+	res = make_dev_argv(ppdev, pargs, fmt, ap);
+	va_end(ap);
+
+	KASSERT(((pargs->flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
+	    ((pargs->flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
+	    ("make_dev_args: failed make_dev_argv (error=%d)", res));
+	return (res);
+}
+
 struct cdev *
 make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
     gid_t gid, int mode, const char *fmt, ...)
 {
+	struct make_dev_args args = {
+		.version = MAKE_DEV_ARGS_VERSION,
+		.si_cred = cr,
+		.si_drv0 = unit,
+		.si_uid = uid,
+		.si_gid = gid,
+		.si_mode = mode,
+		.si_devsw = devsw,
+	};
 	struct cdev *dev;
 	va_list ap;
 	int res;
 
 	va_start(ap, fmt);
-	res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap);
+	res = make_dev_argv(&dev, &args, fmt, ap);
 	va_end(ap);
 
 	KASSERT(res == 0 && dev != NULL,
-	    ("make_dev_cred: failed make_dev_credv (error=%d)", res));
+	    ("make_dev_cred: failed make_dev_argv (error=%d)", res));
 	return (dev);
 }
 
@@ -848,18 +890,27 @@
 make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr,
     uid_t uid, gid_t gid, int mode, const char *fmt, ...)
 {
+	struct make_dev_args args = {
+		.version = MAKE_DEV_ARGS_VERSION,
+		.flags = flags,
+		.si_cred = cr,
+		.si_drv0 = unit,
+		.si_uid = uid,
+		.si_gid = gid,
+		.si_mode = mode,
+		.si_devsw = devsw,
+	};
 	struct cdev *dev;
 	va_list ap;
 	int res;
 
 	va_start(ap, fmt);
-	res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode,
-	    fmt, ap);
+	res = make_dev_argv(&dev, &args, fmt, ap);
 	va_end(ap);
 
 	KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
 	    ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
-	    ("make_dev_credf: failed make_dev_credv (error=%d)", res));
+	    ("make_dev_credf: failed make_dev_argv (error=%d)", res));
 	return (res == 0 ? dev : NULL);
 }
 
@@ -867,17 +918,25 @@
 make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw,
     struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...)
 {
+	struct make_dev_args args = {
+		.version = MAKE_DEV_ARGS_VERSION,
+		.flags = flags,
+		.si_cred = cr,
+		.si_uid = uid,
+		.si_gid = gid,
+		.si_mode = mode,
+		.si_devsw = devsw,
+	};
 	va_list ap;
 	int res;
 
 	va_start(ap, fmt);
-	res = make_dev_credv(flags, cdev, devsw, 0, cr, uid, gid, mode,
-	    fmt, ap);
+	res = make_dev_argv(cdev, &args, fmt, ap);
 	va_end(ap);
 
 	KASSERT(((flags & MAKEDEV_NOWAIT) != 0 && res == ENOMEM) ||
 	    ((flags & MAKEDEV_CHECKNAME) != 0 && res != ENOMEM) || res == 0,
-	    ("make_dev_p: failed make_dev_credv (error=%d)", res));
+	    ("make_dev_p: failed make_dev_argv (error=%d)", res));
 	return (res);
 }
 
@@ -1298,7 +1357,7 @@
 	}
 	if (unit == -1)
 		unit = low & CLONE_UNITMASK;
-	dev = newdev(csw, unit | extra, ndev);
+	dev = newdev(csw, unit | extra, ndev, NULL, NULL);
 	if (dev->si_flags & SI_CLONELIST) {
 		printf("dev %p (%s) is on clonelist\n", dev, dev->si_name);
 		printf("unit=%d, low=%d, extra=0x%x\n", unit, low, extra);
Index: sys/sys/conf.h
===================================================================
--- sys/sys/conf.h
+++ sys/sys/conf.h
@@ -51,6 +51,21 @@
 struct cdevsw;
 struct file;
 
+#define	MAKE_DEV_ARGS_VERSION	20151002
+
+struct make_dev_args {
+	int version;
+	int flags;
+	int si_drv0;
+	uid_t si_uid;
+	gid_t si_gid;
+	mode_t si_mode;
+	struct cdevsw *si_devsw;
+	struct ucred *si_cred;
+	void *si_drv1;
+	void *si_drv2;
+};
+
 struct cdev {
 	void		*si_spare0;
 	u_int		si_flags;
@@ -240,6 +255,14 @@
 void	dev_ref(struct cdev *dev);
 void	dev_refl(struct cdev *dev);
 void	dev_rel(struct cdev *dev);
+/* convenience wrappers for make_dev_args() */
+#define	MAKE_DEV_ARGS_SUB(...)				\
+    .version = MAKE_DEV_ARGS_VERSION, __VA_ARGS__
+#define	MAKE_DEV_ARGS(ppdev,args,...)			\
+    make_dev_args(ppdev, &(struct make_dev_args){	\
+    MAKE_DEV_ARGS_SUB args}, __VA_ARGS__)
+int	make_dev_args(struct cdev **_ppdev, const struct make_dev_args *_pargs,
+		const char *_fmt, ...) __printflike(3, 4);
 struct cdev *make_dev(struct cdevsw *_devsw, int _unit, uid_t _uid, gid_t _gid,
 		int _perms, const char *_fmt, ...) __printflike(6, 7);
 struct cdev *make_dev_cred(struct cdevsw *_devsw, int _unit,