Index: sbin/geom/core/geom.8
===================================================================
--- sbin/geom/core/geom.8
+++ sbin/geom/core/geom.8
@@ -52,6 +52,11 @@
 .Ar class
 .Cm unload
 .Op Fl v
+.Nm
+.Fl p
+.Ar provider-name
+.Nm
+.Fl t
 .Sh DESCRIPTION
 The
 .Nm
@@ -101,6 +106,15 @@
 Unload the kernel module which implements the given class.
 This command is only available if the given class is loaded as a
 kernel module.
+.El
+.Pp
+Additional options include:
+.Bl -tag -width ".Cm status"
+.It Fl p
+Print detailed information about geom which provides
+.Ar provider-name .
+.It Fl t
+Print provider-consumer relationship as a tree.
 .El
 .Pp
 Class-specific commands are implemented as shared libraries which
Index: sbin/geom/core/geom.c
===================================================================
--- sbin/geom/core/geom.c
+++ sbin/geom/core/geom.c
@@ -40,6 +40,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <string.h>
 #include <unistd.h>
@@ -68,6 +69,7 @@
 #define	GEOM_CLASS_CMDS	0x01
 #define	GEOM_STD_CMDS	0x02
 static struct g_command *find_command(const char *cmdstr, int flags);
+static void list_one_geom_by_provider(const char *provider_name);
 static int std_available(const char *name);
 
 static void std_help(struct gctl_req *req, unsigned flags);
@@ -146,6 +148,8 @@
 
 	if (class_name == NULL) {
 		fprintf(stderr, "usage: geom <class> <command> [options]\n");
+		fprintf(stderr, "       geom -p <provider-name>\n");
+		fprintf(stderr, "       geom -t\n");
 		exit(EXIT_FAILURE);
 	} else {
 		struct g_command *cmd;
@@ -650,10 +654,118 @@
 		usage();
 }
 
+static struct ggeom *
+find_geom_by_provider(struct gmesh *mesh, const char *name)
+{
+	struct gclass *classp;
+	struct ggeom *gp;
+	struct gprovider *pp;
+
+	LIST_FOREACH(classp, &mesh->lg_class, lg_class) {
+		LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
+			LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
+				if (strcmp(pp->lg_name, name) == 0)
+					return gp;
+			}
+		}
+	}
+
+	return (NULL);
+}
+
+static void
+show_tree_geom(struct gmesh *mesh, struct ggeom *gp, int indent)
+{
+	struct gclass *classp2;
+	struct ggeom *gp2;
+	struct gconsumer *cp2;
+	struct gprovider *pp;
+	int width;
+
+	width = 20 - indent;
+
+	LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
+		printf("%*s%-*.*s\t%-*.*s\t%s\n", indent, "",
+		    width, width, pp->lg_name,
+		    width, width, gp->lg_name,
+		    gp->lg_class->lg_name);
+
+		LIST_FOREACH(classp2, &mesh->lg_class, lg_class) {
+			LIST_FOREACH(gp2, &classp2->lg_geom, lg_geom) {
+				LIST_FOREACH(cp2, &gp2->lg_consumer, lg_consumer) {
+					if (pp == cp2->lg_provider)
+						show_tree_geom(mesh, gp2, indent + 2);
+				}
+			}
+		}
+	}
+}
+
+static void
+show_tree(void)
+{
+	struct gmesh mesh;
+	struct gclass *classp;
+	struct ggeom *gp;
+	int error;
+
+	error = geom_gettree(&mesh);
+	if (error != 0)
+		errc(EXIT_FAILURE, error, "Cannot get GEOM tree");
+
+	printf("%-*.*s\t%-*.*s\t%s\n", 20, 20, "Provider", 20, 20, "Geom", "Class");
+
+	LIST_FOREACH(classp, &mesh.lg_class, lg_class) {
+		LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
+			if (!LIST_EMPTY(&gp->lg_consumer))
+				continue;
+			show_tree_geom(&mesh, gp, 0);
+		}
+	}
+}
+
 int
 main(int argc, char *argv[])
 {
+	char *provider_name = NULL;
+	bool tflag = false;
+	int ch;
 
+	if (strcmp(getprogname(), "geom") == 0) {
+		while ((ch = getopt(argc, argv, "hp:t")) != -1) {
+			switch (ch) {
+			case 'p':
+				provider_name = strdup(optarg);
+				if (provider_name == NULL)
+					err(1, "strdup");
+				break;
+			case 't':
+				tflag = true;
+				break;
+			case 'h':
+			default:
+				usage();
+			}
+		}
+
+		/*
+		 * Don't adjust argc and argv, it would break get_class().
+		 */
+	}
+
+	if (tflag && provider_name != NULL)
+		errx(EXIT_FAILURE, "at most one of -P and -t may be specified");
+
+	if (provider_name) {
+		list_one_geom_by_provider(provider_name);
+		return (0);
+	}
+
+	if (tflag) {
+		show_tree();
+		return (0);
+	}
+
 	get_class(&argc, &argv);
 	run_command(argc, argv);
 	/* NOTREACHED */
@@ -765,6 +877,25 @@
 		}
 	}
 	printf("\n");
+}
+
+static void
+list_one_geom_by_provider(const char *provider_name)
+{
+	struct gmesh mesh;
+	struct ggeom *gp;
+	int error;
+
+	error = geom_gettree(&mesh);
+	if (error != 0)
+		errc(EXIT_FAILURE, error, "Cannot get GEOM tree");
+
+	gp = find_geom_by_provider(&mesh, provider_name);
+	if (gp == NULL)
+		errx(EXIT_FAILURE, "Cannot find provider '%s'", provider_name);
+
+	printf("Geom class: %s\n", gp->lg_class->lg_name);
+	list_one_geom(gp);
 }
 
 static void