Index: head/usr.sbin/efibootmgr/efibootmgr.8
===================================================================
--- head/usr.sbin/efibootmgr/efibootmgr.8
+++ head/usr.sbin/efibootmgr/efibootmgr.8
@@ -49,7 +49,12 @@
 .Op Fl b Ar bootnum
 .Op Fl k Ar kernel
 .Op Fl L Ar label
+.Op Fl e Ar env
 .Nm
+.Fl E
+.Op Fl d
+.Op Fl p
+.Nm
 .Fl n
 .Fl b Ar bootnum
 .Nm
@@ -111,6 +116,21 @@
 variable.
 .It Fl D -dry-run
 Process but do not change any variables.
+.It Fl E -esp
+Print the
+.Fx
+path to the ESP device, derived from the EFI variables
+.Va BootCurrent
+and
+.Va BootXXXX .
+This is the ESP partition used by UEFI to boot the current
+instance of the system.
+If
+.Fl d -device-path
+is specified, the UEFI device path to the ESP is reported instead.
+If
+.Fl p -unix-path
+is specified, the mount point of the ESP is reported instead.
 .It Fl k -kernel Ar kernel
 The path to and name of the kernel.
 .It Fl l -loader Ar loader
Index: head/usr.sbin/efibootmgr/efibootmgr.c
===================================================================
--- head/usr.sbin/efibootmgr/efibootmgr.c
+++ head/usr.sbin/efibootmgr/efibootmgr.c
@@ -81,6 +81,8 @@
 	bool    delete_bootnext;
 	bool    del_timeout;
 	bool    dry_run;
+	bool	device_path;
+	bool	esp_device;
 	bool	has_bootnum;
 	bool    once;
 	int	cp_src;
@@ -89,6 +91,7 @@
 	bool    set_inactive;
 	bool    set_timeout;
 	int     timeout;
+	bool	unix_path;
 	bool    verbose;
 } bmgr_opts_t;
 
@@ -103,14 +106,17 @@
 	{"del-timout", no_argument, NULL, 'T'},
 	{"delete", no_argument, NULL, 'B'},
 	{"delete-bootnext", no_argument, NULL, 'N'},
+	{"device-path", no_argument, NULL, 'd'},
 	{"dry-run", no_argument, NULL, 'D'},
 	{"env", required_argument, NULL, 'e'},
+	{"esp", no_argument, NULL, 'E'},
 	{"help", no_argument, NULL, 'h'},
 	{"kernel", required_argument, NULL, 'k'},
 	{"label", required_argument, NULL, 'L'},
 	{"loader", required_argument, NULL, 'l'},
 	{"once", no_argument, NULL, 'O'},
 	{"set-timeout", required_argument, NULL, 't'},
+	{"unix-path", no_argument, NULL, 'p'},
 	{"verbose", no_argument, NULL, 'v'},
 	{ NULL, 0, NULL, 0}
 };
@@ -191,7 +197,7 @@
 {
 	int ch;
 
-	while ((ch = getopt_long(argc, argv, "AaBb:C:cDe:hk:L:l:NnOo:Tt:v",
+	while ((ch = getopt_long(argc, argv, "AaBb:C:cdDe:Ehk:L:l:NnOo:pTt:v",
 		    lopts, NULL)) != -1) {
 		switch (ch) {
 		case 'A':
@@ -216,10 +222,16 @@
 		case 'D': /* should be remove dups XXX */
 			opts.dry_run = true;
 			break;
+		case 'd':
+			opts.device_path = true;
+			break;
 		case 'e':
 			free(opts.env);
 			opts.env = strdup(optarg);
 			break;
+		case 'E':
+			opts.esp_device = true;
+			break;
 		case 'h':
 		default:
 			errx(1, "%s", USAGE);
@@ -250,6 +262,9 @@
 			free(opts.order);
 			opts.order = strdup(optarg);
 			break;
+		case 'p':
+			opts.unix_path = true;
+			break;
 		case 'T':
 			opts.del_timeout = true;
 			break;
@@ -906,6 +921,72 @@
 		errx(1, "Can't set Timeout for booting.");
 }
 
+static void
+report_esp_device(bool do_dp, bool do_unix)
+{
+	uint8_t *data;
+	size_t size, len;
+	uint32_t attrs;
+	int ret;
+	uint16_t current, fplen;
+	char *name, *dev, *relpath, *abspath;
+	uint8_t *walker, *ep;
+	efi_char *descr;
+	efidp dp, edp;
+	char buf[PATH_MAX];
+
+	if (do_dp && do_unix)
+		errx(1, "Can't report both UEFI device-path and Unix path together");
+
+	ret = efi_get_variable(EFI_GLOBAL_GUID, "BootCurrent", &data, &size,&attrs);
+	if (ret < 0)
+		err(1, "Can't get BootCurrent");
+	current = le16dec(data);
+	if (asprintf(&name, "Boot%04X", current) < 0)
+		err(1, "Can't format boot var\n");
+	if (efi_get_variable(EFI_GLOBAL_GUID, name, &data, &size, NULL) < 0)
+		err(1, "Can't retrieve EFI var %s", name);
+	// First 4 bytes are attribute flags
+	walker = data;
+	ep = walker + size;
+	walker += sizeof(uint32_t);
+	// Next two bytes are length of the file paths
+	fplen = le16dec(walker);
+	walker += sizeof(fplen);
+	// Next we have a 0 terminated UCS2 string that we know to be aligned
+	descr = (efi_char *)(intptr_t)(void *)walker;
+	len = ucs2len(descr); // XXX need to sanity check that len < (datalen - (ep - walker) / 2)
+	walker += (len + 1) * sizeof(efi_char);
+	if (walker > ep)
+		errx(1, "malformed boot variable %s", name);
+	// Now we have fplen bytes worth of file path stuff
+	dp = (efidp)walker;
+	walker += fplen;
+	edp = (efidp)walker;
+	if (walker > ep)
+		errx(1, "malformed boot variable %s", name);
+	if (do_dp) {
+		efidp_format_device_path_node(buf, sizeof(buf), dp);
+		printf("%s\n", buf);
+		exit(0);
+	}
+	if (efivar_device_path_to_unix_path(dp, &dev, &relpath, &abspath) < 0)
+		errx(1, "Can't convert to unix path");
+	if (do_unix) {
+		if (abspath == NULL)
+			errx(1, "Can't find where %s:%s is mounted",
+			    dev, relpath);
+		abspath[strlen(abspath) - strlen(relpath) - 1] = '\0';
+		printf("%s\n", abspath);
+	} else {
+		printf("%s\n", dev);
+	}
+	free(dev);
+	free(relpath);
+	free(abspath);
+	exit(0);
+}
+
 int
 main(int argc, char *argv[])
 {
@@ -938,6 +1019,8 @@
 		delete_timeout();
 	else if (opts.set_timeout)
 		handle_timeout(opts.timeout);
+	else if (opts.esp_device)
+		report_esp_device(opts.device_path, opts.unix_path);
 
 	print_boot_vars(opts.verbose);
 }