Index: sys/geom/cache/g_cache.c
===================================================================
--- sys/geom/cache/g_cache.c
+++ sys/geom/cache/g_cache.c
@@ -726,11 +726,9 @@
 
 	strlcpy(md.md_magic, G_CACHE_MAGIC, sizeof(md.md_magic));
 	md.md_version = G_CACHE_VERSION;
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg0' argument");
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	strlcpy(md.md_name, name, sizeof(md.md_name));
 
 	size = gctl_get_paraml(req, "size", sizeof(*size));
@@ -790,11 +788,9 @@
 		return;
 	}
 
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg0' argument");
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_cache_find_device(mp, name);
 	if (sc == NULL) {
 		G_CACHE_DEBUG(1, "Device %s is invalid.", name);
@@ -875,11 +871,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%d' argument", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_cache_find_device(mp, name);
 		if (sc == NULL) {
 			G_CACHE_DEBUG(1, "Device %s is invalid.", name);
@@ -917,11 +911,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%d' argument", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_cache_find_device(mp, name);
 		if (sc == NULL) {
 			G_CACHE_DEBUG(1, "Device %s is invalid.", name);
Index: sys/geom/concat/g_concat.c
===================================================================
--- sys/geom/concat/g_concat.c
+++ sys/geom/concat/g_concat.c
@@ -869,11 +869,9 @@
 	bzero(&md, sizeof(md));
 	strlcpy(md.md_magic, G_CONCAT_MAGIC, sizeof(md.md_magic));
 	md.md_version = G_CONCAT_VERSION;
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	strlcpy(md.md_name, name, sizeof(md.md_name));
 	md.md_id = arc4random();
 	md.md_no = 0;
@@ -902,7 +900,7 @@
 		snprintf(param, sizeof(param), "arg%u", no);
 		pp = gctl_get_provider(req, param);
 		if (pp == NULL) {
-			name = gctl_get_asciiparam(req, param);
+			name = gctl_get_devname(req, param);
 			MPASS(name != NULL);
 			sbuf_printf(sb, " %s", name);
 			continue;
@@ -929,9 +927,6 @@
 	struct g_concat_softc *sc;
 	struct g_geom *gp;
 
-	if (strncmp(name, _PATH_DEV, strlen(_PATH_DEV)) == 0)
-		name += strlen(_PATH_DEV);
-
 	LIST_FOREACH(gp, &mp->geom, geom) {
 		sc = gp->softc;
 		if (sc == NULL)
@@ -970,11 +965,9 @@
 
 	for (i = 0; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_concat_find_device(mp, name);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", name);
@@ -995,8 +988,7 @@
 	struct g_concat_disk *disk;
 
 	sx_assert(&sc->sc_disks_lock, SX_LOCKED);
-	if (strncmp(name, "/dev/", 5) == 0)
-		name += 5;
+	name = g_canonical_name(name);
 	TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
 		if (disk->d_consumer == NULL)
 			continue;
@@ -1081,11 +1073,9 @@
 		return;
 	}
 
-	cname = gctl_get_asciiparam(req, "arg0");
-	if (cname == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	cname = gctl_get_devname(req, "arg0");
+	if (cname == NULL)
 		return;
-	}
 	sc = g_concat_find_device(mp, cname);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", cname);
@@ -1104,13 +1094,9 @@
 	gp = sc->sc_geom;
 	fcp = LIST_FIRST(&gp->consumer);
 
-	name = gctl_get_asciiparam(req, "arg1");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 1);
+	name = gctl_get_devname(req, "arg1");
+	if (name == NULL)
 		goto fail;
-	}
-	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
-		name += strlen("/dev/");
 	pp = g_provider_by_name(name);
 	if (pp == NULL) {
 		G_CONCAT_DEBUG(1, "Disk %s is invalid.", name);
Index: sys/geom/eli/g_eli_ctl.c
===================================================================
--- sys/geom/eli/g_eli_ctl.c
+++ sys/geom/eli/g_eli_ctl.c
@@ -174,8 +174,6 @@
 	struct g_provider *pp;
 	struct g_consumer *cp;
 
-	if (strncmp(prov, _PATH_DEV, strlen(_PATH_DEV)) == 0)
-		prov += strlen(_PATH_DEV);
 	LIST_FOREACH(gp, &mp->geom, geom) {
 		sc = gp->softc;
 		if (sc == NULL)
@@ -225,11 +223,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		prov = gctl_get_asciiparam(req, param);
-		if (prov == NULL) {
-			gctl_error(req, "No 'arg%d' argument.", i);
+		prov = gctl_get_devname(req, param);
+		if (prov == NULL)
 			return;
-		}
 		sc = g_eli_find_device(mp, prov);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", prov);
@@ -487,11 +483,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		prov = gctl_get_asciiparam(req, param);
-		if (prov == NULL) {
-			gctl_error(req, "No 'arg%d' argument.", i);
+		prov = gctl_get_devname(req, param);
+		if (prov == NULL)
 			return;
-		}
 		sc = g_eli_find_device(mp, prov);
 		if (sc == NULL) {
 			/*
@@ -652,11 +646,9 @@
 
 	g_topology_assert();
 
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	key = gctl_get_param(req, "key", &keysize);
 	if (key == NULL || keysize != G_ELI_USERKEYLEN) {
 		gctl_error(req, "No '%s' argument.", "key");
@@ -764,11 +756,9 @@
 
 	nkey = 0;	/* fixes causeless gcc warning */
 
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_eli_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "Provider %s is invalid.", name);
@@ -951,11 +941,9 @@
 
 		for (i = 0; i < *nargs; i++) {
 			snprintf(param, sizeof(param), "arg%d", i);
-			prov = gctl_get_asciiparam(req, param);
-			if (prov == NULL) {
-				G_ELI_DEBUG(0, "No 'arg%d' argument.", i);
+			prov = gctl_get_devname(req, param);
+			if (prov == NULL)
 				continue;
-			}
 
 			sc = g_eli_find_device(mp, prov);
 			if (sc == NULL) {
@@ -991,11 +979,9 @@
 		return;
 	}
 
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	key = gctl_get_param(req, "key", &keysize);
 	if (key == NULL || keysize != G_ELI_USERKEYLEN) {
 		gctl_error(req, "No '%s' argument.", "key");
@@ -1142,11 +1128,9 @@
 
 		for (i = 0; i < *nargs; i++) {
 			snprintf(param, sizeof(param), "arg%d", i);
-			prov = gctl_get_asciiparam(req, param);
-			if (prov == NULL) {
-				G_ELI_DEBUG(0, "No 'arg%d' argument.", i);
+			prov = gctl_get_devname(req, param);
+			if (prov == NULL)
 				continue;
-			}
 
 			sc = g_eli_find_device(mp, prov);
 			if (sc == NULL) {
Index: sys/geom/geom.h
===================================================================
--- sys/geom/geom.h
+++ sys/geom/geom.h
@@ -421,11 +421,22 @@
 
 int g_is_geom_thread(struct thread *td);
 
+#else
+#include <paths.h>
+#include <string.h>
+#endif /* _KERNEL */
+
 #ifndef	_PATH_DEV
 #define	_PATH_DEV	"/dev/"
 #endif
 
-#endif /* _KERNEL */
+static __inline const char *
+g_canonical_name(const char *path)
+{
+        if (strncmp(path, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
+                path += sizeof(_PATH_DEV) - 1;
+        return (path);
+}
 
 /* geom_ctl.c */
 int gctl_set_param(struct gctl_req *req, const char *param, void const *ptr, int len);
@@ -439,6 +450,7 @@
 void gctl_msg(struct gctl_req *req, const char *fmt, ...) __printflike(2, 3);
 void gctl_post_messages(struct gctl_req *req);
 struct g_class *gctl_get_class(struct gctl_req *req, char const *arg);
+const char *gctl_get_devname(struct gctl_req *, const char *);
 struct g_geom *gctl_get_geom(struct gctl_req *req, struct g_class *mp, char const *arg);
 struct g_provider *gctl_get_provider(struct gctl_req *req, char const *arg);
 
Index: sys/geom/geom_ctl.c
===================================================================
--- sys/geom/geom_ctl.c
+++ sys/geom/geom_ctl.c
@@ -436,6 +436,20 @@
 	return (p);
 }
 
+const char *
+gctl_get_devname(struct gctl_req *req, const char *param)
+{
+	const char *name;
+
+	name = gctl_get_asciiparam(req, param);
+	if (name == NULL)
+		gctl_error(req, "Missing %s argument", param);
+	else
+		name = g_canonical_name(name);
+
+	return (name);
+}
+
 struct g_class *
 gctl_get_class(struct gctl_req *req, char const *arg)
 {
@@ -480,11 +494,9 @@
 	char const *p;
 	struct g_provider *pp;
 
-	p = gctl_get_asciiparam(req, arg);
-	if (p == NULL) {
-		gctl_error(req, "Missing '%s' argument", arg);
+	p = gctl_get_devname(req, arg);
+	if (p == NULL)
 		return (NULL);
-	}
 	pp = g_provider_by_name(p);
 	if (pp != NULL)
 		return (pp);
Index: sys/geom/geom_dev.c
===================================================================
--- sys/geom/geom_dev.c
+++ sys/geom/geom_dev.c
@@ -179,9 +179,8 @@
 {
 	struct diocskerneldump_arg kda;
 	struct g_consumer *cp;
-	const char *devprefix = _PATH_DEV, *devname;
+	const char *devname;
 	int error;
-	size_t len;
 
 	bzero(&kda, sizeof(kda));
 	kda.kda_index = KDA_APPEND;
@@ -189,11 +188,8 @@
 	if (dumpdev == NULL)
 		return (0);
 
-	len = strlen(devprefix);
 	devname = devtoname(dev);
-	if (strcmp(devname, dumpdev) != 0 &&
-	   (strncmp(dumpdev, devprefix, len) != 0 ||
-	    strcmp(devname, dumpdev + len) != 0))
+	if (strcmp(devname, g_canonical_name(dumpdev)) != 0)
 		return (0);
 
 	cp = (struct g_consumer *)dev->si_drv2;
Index: sys/geom/geom_subr.c
===================================================================
--- sys/geom/geom_subr.c
+++ sys/geom/geom_subr.c
@@ -765,8 +765,7 @@
 	struct g_geom *gp;
 	struct g_provider *pp, *wpp;
 
-	if (strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
-		arg += sizeof(_PATH_DEV) - 1;
+	arg = g_canonical_name(arg);
 
 	wpp = NULL;
 	LIST_FOREACH(cp, &g_classes, class) {
Index: sys/geom/journal/g_journal.c
===================================================================
--- sys/geom/journal/g_journal.c
+++ sys/geom/journal/g_journal.c
@@ -2512,8 +2512,6 @@
 	struct g_geom *gp;
 	struct g_provider *pp;
 
-	if (strncmp(name, _PATH_DEV, 5) == 0)
-		name += 5;
 	LIST_FOREACH(gp, &mp->geom, geom) {
 		sc = gp->softc;
 		if (sc == NULL)
@@ -2554,11 +2552,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%d' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_journal_find_device(mp, name);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", name);
Index: sys/geom/label/g_label.c
===================================================================
--- sys/geom/label/g_label.c
+++ sys/geom/label/g_label.c
@@ -475,8 +475,6 @@
 {
 	u_int i;
 
-	if (strncmp(name, _PATH_DEV, strlen(_PATH_DEV)) == 0)
-		name += strlen(_PATH_DEV);
 	for (i = 0; g_labels[i] != NULL; i++) {
 		if (strncmp(name, g_labels[i]->ld_dirprefix,
 		    strlen(g_labels[i]->ld_dirprefix)) == 0) {
@@ -531,11 +529,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%d' argument", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		gp = g_label_find_geom(mp, name);
 		if (gp == NULL) {
 			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
Index: sys/geom/mirror/g_mirror_ctl.c
===================================================================
--- sys/geom/mirror/g_mirror_ctl.c
+++ sys/geom/mirror/g_mirror_ctl.c
@@ -131,8 +131,6 @@
 	struct g_mirror_disk *disk;
 
 	sx_assert(&sc->sc_lock, SX_XLOCKED);
-	if (strncmp(name, _PATH_DEV, 5) == 0)
-		name += 5;
 	LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 		if (disk->d_consumer == NULL)
 			continue;
@@ -165,11 +163,9 @@
 		gctl_error(req, "Invalid number of arguments.");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	balancep = gctl_get_asciiparam(req, "balance");
 	if (balancep == NULL) {
 		gctl_error(req, "No '%s' argument.", "balance");
@@ -220,7 +216,7 @@
 	 * Note: be WARNS safe, by always assigning prov and only throw an
 	 * error if *priority != -1.
 	 */
-	prov = gctl_get_asciiparam(req, "arg1");
+	prov = gctl_get_devname(req, "arg1");
 	if (*priority > -1) {
 		if (prov == NULL) {
 			gctl_error(req, "Priority needs a disk name");
@@ -393,11 +389,9 @@
 
 	strlcpy(md.md_magic, G_MIRROR_MAGIC, sizeof(md.md_magic));
 	md.md_version = G_MIRROR_VERSION;
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	strlcpy(md.md_name, name, sizeof(md.md_name));
 	md.md_mid = arc4random();
 	md.md_all = *nargs - 1;
@@ -497,7 +491,7 @@
 		snprintf(param, sizeof(param), "arg%u", no);
 		pp = gctl_get_provider(req, param);
 		if (pp == NULL) {
-			name = gctl_get_asciiparam(req, param);
+			name = gctl_get_devname(req, param);
 			MPASS(name != NULL);
 			sbuf_printf(sb, " %s", name);
 			continue;
@@ -544,11 +538,9 @@
 		gctl_error(req, "Too few arguments.");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_mirror_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
@@ -556,11 +548,9 @@
 	}
 	for (i = 1; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			continue;
-		}
 		disk = g_mirror_find_disk(sc, name);
 		if (disk == NULL) {
 			gctl_error(req, "No such provider: %s.", name);
@@ -650,11 +640,9 @@
 		gctl_error(req, "No '%s' argument.", "hardcode");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_mirror_find_launched_device(mp, name, M_WAITOK);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
@@ -809,11 +797,9 @@
 		gctl_error(req, "Too few arguments.");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_mirror_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
@@ -828,11 +814,9 @@
 	active = g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE);
 	for (i = 1; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			continue;
-		}
 		disk = g_mirror_find_disk(sc, name);
 		if (disk == NULL) {
 			gctl_error(req, "No such provider: %s.", name);
@@ -873,11 +857,9 @@
 		gctl_error(req, "Missing device.");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	s = gctl_get_asciiparam(req, "size");
 	if (s == NULL) {
 		gctl_error(req, "No '%s' argument.", "size");
@@ -941,11 +923,9 @@
 		gctl_error(req, "Too few arguments.");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_mirror_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
@@ -954,11 +934,9 @@
 	active = g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE);
 	for (i = 1; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			continue;
-		}
 		disk = g_mirror_find_disk(sc, name);
 		if (disk == NULL) {
 			gctl_error(req, "No such provider: %s.", name);
@@ -1006,11 +984,9 @@
 
 	for (i = 0; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_mirror_find_device(mp, name);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", name);
@@ -1062,11 +1038,9 @@
 
 	for (i = 0; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_mirror_find_device(mp, name);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", name);
Index: sys/geom/mountver/g_mountver.c
===================================================================
--- sys/geom/mountver/g_mountver.c
+++ sys/geom/mountver/g_mountver.c
@@ -466,13 +466,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%d' argument", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
-		if (strncmp(name, _PATH_DEV, strlen(_PATH_DEV)) == 0)
-			name += strlen(_PATH_DEV);
 		gp = g_mountver_find_geom(mp, name);
 		if (gp == NULL) {
 			G_MOUNTVER_DEBUG(1, "Device %s is invalid.", name);
Index: sys/geom/multipath/g_multipath.c
===================================================================
--- sys/geom/multipath/g_multipath.c
+++ sys/geom/multipath/g_multipath.c
@@ -951,16 +951,13 @@
 	struct g_consumer *cp;
 	struct g_provider *pp;
 	const char *mpname;
-	static const char devpf[6] = _PATH_DEV;
 	int error;
 
 	g_topology_assert();
 
-	mpname = gctl_get_asciiparam(req, "arg0");
-        if (mpname == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	mpname = gctl_get_devname(req, "arg0");
+        if (mpname == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, mpname);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s is invalid", mpname);
@@ -968,8 +965,6 @@
 	}
 	sc = gp->softc;
 
-	if (strncmp(name, devpf, 5) == 0)
-		name += 5;
 	pp = g_provider_by_name(name);
 	if (pp == NULL) {
 		gctl_error(req, "Provider %s is invalid", name);
@@ -1014,16 +1009,13 @@
 	struct g_multipath_softc *sc;
 	struct g_consumer *cp;
 	const char *name, *mpname;
-	static const char devpf[6] = _PATH_DEV;
 	int *nargs;
 
 	g_topology_assert();
 
-	mpname = gctl_get_asciiparam(req, "arg0");
-        if (mpname == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	mpname = gctl_get_devname(req, "arg0");
+        if (mpname == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, mpname);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s is invalid", mpname);
@@ -1041,14 +1033,9 @@
 		return;
 	}
 
-	name = gctl_get_asciiparam(req, "arg1");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg1' argument");
+	name = gctl_get_devname(req, "arg1");
+	if (name == NULL)
 		return;
-	}
-	if (strncmp(name, devpf, 5) == 0) {
-		name += 5;
-	}
 
 	LIST_FOREACH(cp, &gp->consumer, consumer) {
 		if (cp->provider != NULL
@@ -1085,22 +1072,18 @@
 	struct g_geom *gp;
 	const char *mpname, *name;
 
-	mpname = gctl_get_asciiparam(req, "arg0");
-        if (mpname == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	mpname = gctl_get_devname(req, "arg0");
+        if (mpname == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, mpname);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s not found", mpname);
 		return;
 	}
 
-	name = gctl_get_asciiparam(req, "arg1");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg1' argument");
+	name = gctl_get_devname(req, "arg1");
+	if (name == NULL)
 		return;
-	}
 	g_multipath_ctl_add_name(req, mp, name);
 }
 
@@ -1122,11 +1105,9 @@
 		return;
 	}
 
-	mpname = gctl_get_asciiparam(req, "arg0");
-        if (mpname == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	mpname = gctl_get_devname(req, "arg0");
+        if (mpname == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, mpname);
 	if (gp != NULL) {
 		gctl_error(req, "Device %s already exist", mpname);
@@ -1157,7 +1138,9 @@
 
 	for (i = 1; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
+			continue;
 		g_multipath_ctl_add_name(req, mp, name);
 	}
 
@@ -1178,11 +1161,9 @@
 
 	g_topology_assert();
 
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg0' argument");
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	gp = g_multipath_find_geom(mp, name);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s is invalid", name);
@@ -1224,11 +1205,9 @@
 	const char *mpname, *name;
 	int found;
 
-	mpname = gctl_get_asciiparam(req, "arg0");
-        if (mpname == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	mpname = gctl_get_devname(req, "arg0");
+        if (mpname == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, mpname);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s not found", mpname);
@@ -1236,11 +1215,9 @@
 	}
 	sc = gp->softc;
 
-	name = gctl_get_asciiparam(req, "arg1");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg1' argument");
+	name = gctl_get_devname(req, "arg1");
+	if (name == NULL)
 		return;
-	}
 
 	found = 0;
 	mtx_lock(&sc->sc_mtx);
@@ -1279,11 +1256,9 @@
 	uintptr_t *cnt;
 	int found;
 
-	mpname = gctl_get_asciiparam(req, "arg0");
-        if (mpname == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	mpname = gctl_get_devname(req, "arg0");
+        if (mpname == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, mpname);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s not found", mpname);
@@ -1291,11 +1266,9 @@
 	}
 	sc = gp->softc;
 
-	name = gctl_get_asciiparam(req, "arg1");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg1' argument");
+	name = gctl_get_devname(req, "arg1");
+	if (name == NULL)
 		return;
-	}
 
 	found = 0;
 	mtx_lock(&sc->sc_mtx);
@@ -1351,11 +1324,9 @@
 
 	g_topology_assert();
 
-	name = gctl_get_asciiparam(req, "arg0");
-        if (name == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	name = gctl_get_devname(req, "arg0");
+        if (name == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, name);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s is invalid", name);
@@ -1379,11 +1350,9 @@
 
 	g_topology_assert();
 
-	name = gctl_get_asciiparam(req, "arg0");
-        if (name == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	name = gctl_get_devname(req, "arg0");
+        if (name == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, name);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s is invalid", name);
@@ -1425,11 +1394,9 @@
 
 	g_topology_assert();
 
-	name = gctl_get_asciiparam(req, "arg0");
-        if (name == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	name = gctl_get_devname(req, "arg0");
+        if (name == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, name);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s is invalid", name);
@@ -1454,11 +1421,9 @@
 	sb = sbuf_new_auto();
 
 	g_topology_assert();
-	name = gctl_get_asciiparam(req, "arg0");
-        if (name == NULL) {
-                gctl_error(req, "No 'arg0' argument");
+	name = gctl_get_devname(req, "arg0");
+        if (name == NULL)
                 return;
-        }
 	gp = g_multipath_find_geom(mp, name);
 	if (gp == NULL) {
 		gctl_error(req, "Device %s is invalid", name);
Index: sys/geom/nop/g_nop.c
===================================================================
--- sys/geom/nop/g_nop.c
+++ sys/geom/nop/g_nop.c
@@ -665,8 +665,8 @@
 			return;
 		}
 	}
-	physpath = gctl_get_asciiparam(req, "physpath");
-	gnopname = gctl_get_asciiparam(req, "gnopname");
+	physpath = gctl_get_devname(req, "physpath");
+	gnopname = gctl_get_devname(req, "gnopname");
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
@@ -835,13 +835,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%d' argument", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
-		if (strncmp(name, _PATH_DEV, strlen(_PATH_DEV)) == 0)
-			name += strlen(_PATH_DEV);
 		gp = g_nop_find_geom(mp, name);
 		if (gp == NULL) {
 			G_NOP_DEBUG(1, "Device %s is invalid.", name);
Index: sys/geom/part/g_part.c
===================================================================
--- sys/geom/part/g_part.c
+++ sys/geom/part/g_part.c
@@ -530,11 +530,9 @@
 	struct g_geom *gp;
 	const char *gname;
 
-	gname = gctl_get_asciiparam(req, name);
+	gname = gctl_get_devname(req, name);
 	if (gname == NULL)
 		return (ENOATTR);
-	if (strncmp(gname, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
-		gname += sizeof(_PATH_DEV) - 1;
 	gp = g_part_find_geom(gname);
 	if (gp == NULL) {
 		gctl_error(req, "%d %s '%s'", EINVAL, name, gname);
@@ -551,11 +549,9 @@
 	struct g_provider *pp;
 	const char *pname;
 
-	pname = gctl_get_asciiparam(req, name);
+	pname = gctl_get_devname(req, name);
 	if (pname == NULL)
 		return (ENOATTR);
-	if (strncmp(pname, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
-		pname += sizeof(_PATH_DEV) - 1;
 	pp = g_provider_by_name(pname);
 	if (pp == NULL) {
 		gctl_error(req, "%d %s '%s'", EINVAL, name, pname);
Index: sys/geom/raid/g_raid.c
===================================================================
--- sys/geom/raid/g_raid.c
+++ sys/geom/raid/g_raid.c
@@ -775,8 +775,6 @@
 
 	g_topology_assert();
 
-	if (strncmp(name, _PATH_DEV, 5) == 0)
-		name += 5;
 	pp = g_provider_by_name(name);
 	if (pp == NULL)
 		return (NULL);
Index: sys/geom/raid/md_ddf.c
===================================================================
--- sys/geom/raid/md_ddf.c
+++ sys/geom/raid/md_ddf.c
@@ -2308,9 +2308,8 @@
 		bzero(offs, sizeof(offs));
 		for (i = 0; i < numdisks; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i + 3);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -6;
 				break;
 			}
@@ -2612,14 +2611,11 @@
 		}
 		for (i = 1; i < *nargs; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -2;
 				break;
 			}
-			if (strncmp(diskname, _PATH_DEV, 5) == 0)
-				diskname += 5;
 
 			TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
 				if (disk->d_consumer != NULL && 
@@ -2664,9 +2660,8 @@
 		for (i = 1; i < *nargs; i++) {
 			/* Get disk name. */
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -3;
 				break;
 			}
Index: sys/geom/raid/md_intel.c
===================================================================
--- sys/geom/raid/md_intel.c
+++ sys/geom/raid/md_intel.c
@@ -1747,9 +1747,8 @@
 		sectorsize = 0;
 		for (i = 0; i < numdisks; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i + 3);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -6;
 				break;
 			}
@@ -2199,14 +2198,11 @@
 		}
 		for (i = 1; i < *nargs; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -2;
 				break;
 			}
-			if (strncmp(diskname, _PATH_DEV, 5) == 0)
-				diskname += 5;
 
 			TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
 				if (disk->d_consumer != NULL && 
@@ -2270,9 +2266,8 @@
 		for (i = 1; i < *nargs; i++) {
 			/* Get disk name. */
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -3;
 				break;
 			}
Index: sys/geom/raid/md_jmicron.c
===================================================================
--- sys/geom/raid/md_jmicron.c
+++ sys/geom/raid/md_jmicron.c
@@ -1079,9 +1079,8 @@
 		sectorsize = 0;
 		for (i = 0; i < numdisks; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i + 3);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -6;
 				break;
 			}
@@ -1260,14 +1259,11 @@
 		}
 		for (i = 1; i < *nargs; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -2;
 				break;
 			}
-			if (strncmp(diskname, _PATH_DEV, 5) == 0)
-				diskname += 5;
 
 			TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
 				if (disk->d_consumer != NULL && 
@@ -1331,9 +1327,8 @@
 		for (i = 1; i < *nargs; i++) {
 			/* Get disk name. */
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -3;
 				break;
 			}
Index: sys/geom/raid/md_nvidia.c
===================================================================
--- sys/geom/raid/md_nvidia.c
+++ sys/geom/raid/md_nvidia.c
@@ -1083,9 +1083,8 @@
 		sectorsize = 0;
 		for (i = 0; i < numdisks; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i + 3);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -6;
 				break;
 			}
@@ -1265,14 +1264,11 @@
 		}
 		for (i = 1; i < *nargs; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -2;
 				break;
 			}
-			if (strncmp(diskname, _PATH_DEV, 5) == 0)
-				diskname += 5;
 
 			TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
 				if (disk->d_consumer != NULL && 
@@ -1336,9 +1332,8 @@
 		for (i = 1; i < *nargs; i++) {
 			/* Get disk name. */
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -3;
 				break;
 			}
Index: sys/geom/raid/md_promise.c
===================================================================
--- sys/geom/raid/md_promise.c
+++ sys/geom/raid/md_promise.c
@@ -1319,9 +1319,8 @@
 		bzero(offs, sizeof(offs));
 		for (i = 0; i < numdisks; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i + 3);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -6;
 				break;
 			}
@@ -1601,14 +1600,11 @@
 		}
 		for (i = 1; i < *nargs; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -2;
 				break;
 			}
-			if (strncmp(diskname, _PATH_DEV, 5) == 0)
-				diskname += 5;
 
 			TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
 				if (disk->d_consumer != NULL && 
@@ -1653,9 +1649,8 @@
 		for (i = 1; i < *nargs; i++) {
 			/* Get disk name. */
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -3;
 				break;
 			}
Index: sys/geom/raid/md_sii.c
===================================================================
--- sys/geom/raid/md_sii.c
+++ sys/geom/raid/md_sii.c
@@ -1167,9 +1167,8 @@
 		sectorsize = 0;
 		for (i = 0; i < numdisks; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i + 3);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -6;
 				break;
 			}
@@ -1347,14 +1346,11 @@
 		}
 		for (i = 1; i < *nargs; i++) {
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -2;
 				break;
 			}
-			if (strncmp(diskname, _PATH_DEV, 5) == 0)
-				diskname += 5;
 
 			TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
 				if (disk->d_consumer != NULL && 
@@ -1418,9 +1414,8 @@
 		for (i = 1; i < *nargs; i++) {
 			/* Get disk name. */
 			snprintf(arg, sizeof(arg), "arg%d", i);
-			diskname = gctl_get_asciiparam(req, arg);
+			diskname = gctl_get_devname(req, arg);
 			if (diskname == NULL) {
-				gctl_error(req, "No disk name (%s).", arg);
 				error = -3;
 				break;
 			}
Index: sys/geom/raid3/g_raid3_ctl.c
===================================================================
--- sys/geom/raid3/g_raid3_ctl.c
+++ sys/geom/raid3/g_raid3_ctl.c
@@ -77,8 +77,6 @@
 	u_int n;
 
 	sx_assert(&sc->sc_lock, SX_XLOCKED);
-	if (strncmp(name, _PATH_DEV, 5) == 0)
-		name += 5;
 	for (n = 0; n < sc->sc_ndisks; n++) {
 		disk = &sc->sc_disks[n];
 		if (disk->d_state == G_RAID3_DISK_STATE_NODISK)
@@ -181,11 +179,9 @@
 		gctl_error(req, "Nothing has changed.");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_raid3_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
@@ -278,19 +274,16 @@
 		gctl_error(req, "Invalid number of arguments.");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_raid3_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg1");
+	name = gctl_get_devname(req, "arg1");
 	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 1);
 		sx_xunlock(&sc->sc_lock);
 		return;
 	}
@@ -362,11 +355,9 @@
 
 	for (i = 0; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_raid3_find_device(mp, name);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", name);
@@ -444,11 +435,9 @@
 		goto end;
 	}
 	g_topology_unlock();
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		goto end;
-	}
 	sc = g_raid3_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
@@ -548,11 +537,9 @@
 		gctl_error(req, "No '%s' argument.", "no");
 		return;
 	}
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	sc = g_raid3_find_device(mp, name);
 	if (sc == NULL) {
 		gctl_error(req, "No such device: %s.", name);
Index: sys/geom/shsec/g_shsec.c
===================================================================
--- sys/geom/shsec/g_shsec.c
+++ sys/geom/shsec/g_shsec.c
@@ -768,11 +768,9 @@
 
 	for (i = 0; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_shsec_find_device(mp, name);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", name);
Index: sys/geom/stripe/g_stripe.c
===================================================================
--- sys/geom/stripe/g_stripe.c
+++ sys/geom/stripe/g_stripe.c
@@ -1063,11 +1063,9 @@
 
 	strlcpy(md.md_magic, G_STRIPE_MAGIC, sizeof(md.md_magic));
 	md.md_version = G_STRIPE_VERSION;
-	name = gctl_get_asciiparam(req, "arg0");
-	if (name == NULL) {
-		gctl_error(req, "No 'arg%u' argument.", 0);
+	name = gctl_get_devname(req, "arg0");
+	if (name == NULL)
 		return;
-	}
 	strlcpy(md.md_name, name, sizeof(md.md_name));
 	md.md_id = arc4random();
 	md.md_no = 0;
@@ -1103,7 +1101,7 @@
 		snprintf(param, sizeof(param), "arg%u", no);
 		pp  = gctl_get_provider(req, param);
 		if (pp == NULL) {
-			name = gctl_get_asciiparam(req, param);
+			name = gctl_get_devname(req, param);
 			MPASS(name != NULL);
 			sbuf_printf(sb, " %s", name);
 			continue;
@@ -1168,11 +1166,9 @@
 
 	for (i = 0; i < (u_int)*nargs; i++) {
 		snprintf(param, sizeof(param), "arg%u", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_error(req, "No 'arg%u' argument.", i);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			return;
-		}
 		sc = g_stripe_find_device(mp, name);
 		if (sc == NULL) {
 			gctl_error(req, "No such device: %s.", name);
Index: sys/geom/union/g_union.c
===================================================================
--- sys/geom/union/g_union.c
+++ sys/geom/union/g_union.c
@@ -170,7 +170,10 @@
 	offset = g_union_fetcharg(req, "offset");
 	size = g_union_fetcharg(req, "size");
 	secsize = g_union_fetcharg(req, "secsize");
-	gunionname = gctl_get_asciiparam(req, "gunionname");
+	gunionname = gctl_get_devname(req, "gunionname");
+	if (gunionname == NULL)
+		/* error message provided by gctl_get_devname() */
+		return;
 
 	upperpp = gctl_get_provider(req, "arg0");
 	lowerpp = gctl_get_provider(req, "arg1");
@@ -423,13 +426,9 @@
 
 	for (i = 0; i < *nargs; i++) {
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
-		if (name == NULL) {
-			gctl_msg(req, "No '%s' argument.", param);
+		name = gctl_get_devname(req, param);
+		if (name == NULL)
 			continue;
-		}
-		if (strncmp(name, _PATH_DEV, strlen(_PATH_DEV)) == 0)
-			name += strlen(_PATH_DEV);
 		gp = g_union_find_geom(mp, name);
 		if (gp == NULL) {
 			gctl_msg(req, "Device %s is invalid.", name);
Index: sys/geom/vinum/geom_vinum_share.c
===================================================================
--- sys/geom/vinum/geom_vinum_share.c
+++ sys/geom/vinum/geom_vinum_share.c
@@ -50,7 +50,6 @@
 #include <sys/malloc.h>
 #include <sys/systm.h>
 
-#include <geom/geom.h>
 #define	iswhite(c) (((c) == ' ') || ((c) == '\t'))
 #else
 #include <ctype.h>
@@ -62,6 +61,8 @@
 #define	g_free	free
 #endif /* _KERNEL */
 
+#include <geom/geom.h>
+
 #include <sys/mutex.h>
 #include <sys/queue.h>
 
@@ -440,7 +441,7 @@
 {
 	struct gv_drive *d;
 	int j, errors;
-	char *ptr;
+	const char *ptr;
 
 	if (token[1] == NULL || *token[1] == '\0')
 		return (NULL);
@@ -462,10 +463,8 @@
 				errors++;
 				break;
 			}
-			ptr = token[j];
+			ptr = g_canonical_name(token[j]);
 
-			if (strncmp(ptr, _PATH_DEV, 5) == 0)
-				ptr += 5;
 			strlcpy(d->device, ptr, sizeof(d->device));
 		} else {
 			/* We assume this is the drive name. */
Index: sys/geom/virstor/g_virstor.c
===================================================================
--- sys/geom/virstor/g_virstor.c
+++ sys/geom/virstor/g_virstor.c
@@ -228,9 +228,8 @@
 		int error;
 
 		snprintf(param, sizeof(param), "arg%d", i);
-		name = gctl_get_asciiparam(req, param);
+		name = gctl_get_devname(req, param);
 		if (name == NULL) {
-			gctl_error(req, "No 'arg%d' argument", i);
 			g_topology_unlock();
 			return;
 		}
@@ -289,11 +288,9 @@
 	}
 
 	/* Find "our" geom */
-	geom_name = gctl_get_asciiparam(req, "arg0");
-	if (geom_name == NULL) {
-		gctl_error(req, "Error fetching argument '%s'", "geom_name (arg0)");
+	geom_name = gctl_get_devname(req, "arg0");
+	if (geom_name == NULL)
 		return;
-	}
 	sc = virstor_find_geom(cp, geom_name);
 	if (sc == NULL) {
 		gctl_error(req, "Don't know anything about '%s'", geom_name);
@@ -538,12 +535,9 @@
 		return;
 	}
 	/* Find "our" geom */
-	geom_name = gctl_get_asciiparam(req, "arg0");
-	if (geom_name == NULL) {
-		gctl_error(req, "Error fetching argument '%s'",
-		    "geom_name (arg0)");
+	geom_name = gctl_get_devname(req, "arg0");
+	if (geom_name == NULL)
 		return;
-	}
 	sc = virstor_find_geom(cp, geom_name);
 	if (sc == NULL) {
 		gctl_error(req, "Don't know anything about '%s'", geom_name);
@@ -565,13 +559,9 @@
 		struct g_virstor_component *newcomp, *compbak;
 
 		snprintf(param, sizeof(param), "arg%d", i);
-		prov_name = gctl_get_asciiparam(req, param);
-		if (prov_name == NULL) {
-			gctl_error(req, "Error fetching argument '%s'", param);
+		prov_name = gctl_get_devname(req, param);
+		if (prov_name == NULL)
 			return;
-		}
-		if (strncmp(prov_name, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
-			prov_name += sizeof(_PATH_DEV) - 1;
 
 		found = -1;
 		for (j = 0; j < sc->n_components; j++) {