petitboot: Implement ordered boot options

Move petitboot to a more familiar 'boot-order' based autoboot system.
The discover server now reads multiple values from the petitboot,bootdev
parameter and adds them in order to config->autoboot_opts. Boot priority
is determined by the options' position in the list.
On the client, nc-config now recognises the new boot order, and allows
the user to add, remove, and reorder the devices in the list.

Signed-off-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com>

8 files changed, 419 insertions, 222 deletions

diff --git a/discover/device-handler.c b/discover/device-handler.c
index f053713..487f2e7 100644
--- a/discover/device-handler.c
+++ b/discover/device-handler.c
@@ -40,8 +40,7 @@
 
 enum default_priority {
 	DEFAULT_PRIORITY_REMOTE		= 1,
-	DEFAULT_PRIORITY_LOCAL_UUID	= 2,
-	DEFAULT_PRIORITY_LOCAL_FIRST	= 3,
+	DEFAULT_PRIORITY_LOCAL_FIRST	= 2,
 	DEFAULT_PRIORITY_LOCAL_LAST	= 0xfe,
 	DEFAULT_PRIORITY_DISABLED	= 0xff,
 };
@@ -462,11 +461,27 @@ static bool ipmi_device_type_matches(enum ipmi_bootdev ipmi_type,
 	return false;
 }
 
-static bool priority_matches(struct boot_priority *prio,
-		struct discover_boot_option *opt)
+static int autoboot_option_priority(const struct config *config,
+				struct discover_boot_option *opt)
 {
-	return prio->type == opt->device->device->type ||
-		prio->type == DEVICE_TYPE_ANY;
+	enum device_type type = opt->device->device->type;
+	const char *uuid = opt->device->uuid;
+	struct autoboot_option *auto_opt;
+	unsigned int i;
+
+	for (i = 0; i < config->n_autoboot_opts; i++) {
+		auto_opt = &config->autoboot_opts[i];
+		if (auto_opt->boot_type == BOOT_DEVICE_UUID)
+			if (!strcmp(auto_opt->uuid, uuid))
+				return DEFAULT_PRIORITY_LOCAL_FIRST + i;
+
+		if (auto_opt->boot_type == BOOT_DEVICE_TYPE)
+			if (auto_opt->type == type ||
+			    auto_opt->type == DEVICE_TYPE_ANY)
+				return DEFAULT_PRIORITY_LOCAL_FIRST + i;
+	}
+
+	return -1;
 }
 
 /*
@@ -478,8 +493,6 @@ static enum default_priority default_option_priority(
 		struct discover_boot_option *opt)
 {
 	const struct config *config;
-	const char *dev_str;
-	unsigned int i;
 
 	config = config_get();
 
@@ -498,25 +511,17 @@ static enum default_priority default_option_priority(
 		return DEFAULT_PRIORITY_DISABLED;
 	}
 
-	/* Next, allow matching by device UUID. If we have one set but it
-	 * doesn't match, disallow the default entirely */
-	dev_str = config->boot_device;
-	if (dev_str && dev_str[0]) {
-		if (!strcmp(opt->device->uuid, dev_str))
-			return DEFAULT_PRIORITY_LOCAL_UUID;
-
-		pb_debug("handler: disabled default priority due to "
-				"non-matching UUID\n");
-		return DEFAULT_PRIORITY_DISABLED;
-	}
-
-	/* Lastly, use the local priorities */
-	for (i = 0; i < config->n_boot_priorities; i++) {
-		struct boot_priority *prio = &config->boot_priorities[i];
-		if (priority_matches(prio, opt))
-			return DEFAULT_PRIORITY_LOCAL_FIRST + prio->priority;
+	/* Next, try to match the option against the user-defined autoboot
+	 * options, either by device UUID or type. */
+	if (config->n_autoboot_opts) {
+		int boot_match = autoboot_option_priority(config, opt);
+		if (boot_match > 0)
+			return boot_match;
 	}
 
+	/* If the option didn't match any entry in the array, it is disabled */
+	pb_debug("handler: disabled default priority due to "
+			"non-matching UUID or type\n");
 	return DEFAULT_PRIORITY_DISABLED;
 }
 
diff --git a/discover/platform-powerpc.c b/discover/platform-powerpc.c
index 895f0ec..bbffb60 100644
--- a/discover/platform-powerpc.c
+++ b/discover/platform-powerpc.c
@@ -49,6 +49,7 @@ static const char *known_params[] = {
 	"petitboot,network",
 	"petitboot,timeout",
 	"petitboot,bootdev",
+	"petitboot,bootdevs",
 	"petitboot,language",
 	"petitboot,debug?",
 	NULL,
@@ -431,28 +432,86 @@ static int read_bootdev(void *ctx, char **pos, struct autoboot_option *opt)
 
 static void populate_bootdev_config(struct platform_powerpc *platform,
 		struct config *config)
-
 {
+	struct autoboot_option *opt, *new = NULL;
+	char *pos, *end, *old_dev = NULL;
+	const char delim = ' ';
+	unsigned int n_new = 0;
 	const char *val;
+	bool conflict;
 
-	config->boot_device = NULL;
-
+	/* Check for old-style bootdev */
 	val = get_param(platform, "petitboot,bootdev");
-	if (!val || !strlen(val))
-		return;
-
-	if (!strncmp(val, "uuid:", strlen("uuid:"))) {
-		config->boot_device = talloc_strdup(config,
+	if (val && strlen(val)) {
+		pos = talloc_strdup(config, val);
+		if (!strncmp(val, "uuid:", strlen("uuid:")))
+			old_dev = talloc_strdup(config,
 						val + strlen("uuid:"));
-
-	} else if (!strncmp(val, "mac:", strlen("mac:"))) {
-		config->boot_device = talloc_strdup(config,
+		else if (!strncmp(val, "mac:", strlen("mac:")))
+			old_dev = talloc_strdup(config,
 						val + strlen("mac:"));
+	}
 
+	/* Check for ordered bootdevs */
+	val = get_param(platform, "petitboot,bootdevs");
+	if (!val || !strlen(val)) {
+		pos = end = NULL;
 	} else {
-		pb_log("bootdev config is in an unknown format "
-				"(expected uuid:... or mac:...)");
+		pos = talloc_strdup(config, val);
+		end = strchr(pos, '\0');
+	}
+
+	while (pos && pos < end) {
+		opt = talloc(config, struct autoboot_option);
+
+		if (read_bootdev(config, &pos, opt)) {
+			pb_log("bootdev config is in an unknown format "
+			       "(expected uuid:... or mac:...)");
+			talloc_free(opt);
+			if (strchr(pos, delim))
+				continue;
+			return;
+		}
+
+		new = talloc_realloc(config, new, struct autoboot_option,
+				     n_new + 1);
+		new[n_new] = *opt;
+		n_new++;
+		talloc_free(opt);
+
 	}
+
+	if (!n_new && !old_dev) {
+		/* If autoboot has been disabled, clear the default options */
+		if (!config->autoboot_enabled) {
+			talloc_free(config->autoboot_opts);
+			config->n_autoboot_opts = 0;
+		}
+		return;
+	}
+
+	conflict = old_dev && (!n_new ||
+				    new[0].boot_type == BOOT_DEVICE_TYPE ||
+				    /* Canonical UUIDs are 36 characters long */
+				    strncmp(new[0].uuid, old_dev, 36));
+
+	if (!conflict) {
+		talloc_free(config->autoboot_opts);
+		config->autoboot_opts = new;
+		config->n_autoboot_opts = n_new;
+		return;
+	}
+
+	/*
+	 * Difference detected, defer to old format in case it has been updated
+	 * recently
+	 */
+	pb_debug("Old autoboot bootdev detected\n");
+	talloc_free(config->autoboot_opts);
+	config->autoboot_opts = talloc(config, struct autoboot_option);
+	config->autoboot_opts[0].boot_type = BOOT_DEVICE_UUID;
+	config->autoboot_opts[0].uuid = talloc_strdup(config, old_dev);
+	config->n_autoboot_opts = 1;
 }
 
 static void populate_config(struct platform_powerpc *platform,
@@ -578,16 +637,40 @@ static void update_network_config(struct platform_powerpc *platform,
 static void update_bootdev_config(struct platform_powerpc *platform,
 		struct config *config)
 {
-	char *val, *tmp = NULL;
+	char *val = NULL, *boot_str = NULL, *tmp = NULL, *first = NULL;
+	struct autoboot_option *opt;
+	const char delim = ' ';
+	unsigned int i;
 
-	if (!config->boot_device)
-		val = "";
+	if (!config->n_autoboot_opts)
+		first = val = "";
+	else if (config->autoboot_opts[0].boot_type == BOOT_DEVICE_UUID)
+		first = talloc_asprintf(config, "uuid:%s",
+					config->autoboot_opts[0].uuid);
 	else
-		tmp = val = talloc_asprintf(platform,
-				"uuid:%s", config->boot_device);
+		first = "";
+
+	for (i = 0; i < config->n_autoboot_opts; i++) {
+		opt = &config->autoboot_opts[i];
+		switch (opt->boot_type) {
+			case BOOT_DEVICE_TYPE:
+				boot_str = talloc_asprintf(config, "%s%c",
+						device_type_name(opt->type),
+						delim);
+				break;
+			case BOOT_DEVICE_UUID:
+				boot_str = talloc_asprintf(config, "uuid:%s%c",
+						opt->uuid, delim);
+				break;
+			}
+			tmp = val = talloc_asprintf_append(val, boot_str);
+	}
 
-	update_string_config(platform, "petitboot,bootdev", val);
+	update_string_config(platform, "petitboot,bootdevs", val);
+	update_string_config(platform, "petitboot,bootdev", first);
 	talloc_free(tmp);
+	if (boot_str)
+		talloc_free(boot_str);
 }
 
 static int update_config(struct platform_powerpc *platform,
diff --git a/discover/platform.c b/discover/platform.c
index 4451589..74e2a82 100644
--- a/discover/platform.c
+++ b/discover/platform.c
@@ -62,16 +62,13 @@ static void dump_config(struct config *config)
 	for (i = 0; i < config->network.n_dns_servers; i++)
 		pb_log("  dns server %s\n", config->network.dns_servers[i]);
 
-	if (config->boot_device)
-		pb_log("  boot device %s\n", config->boot_device);
-
-	if (config->n_boot_priorities)
-		pb_log(" boot priority order:\n");
-
-	for (i = 0; i < config->n_boot_priorities; i++) {
-		struct boot_priority *prio = &config->boot_priorities[i];
-		pb_log(" %10s: %d\n", device_type_name(prio->type),
-					prio->priority);
+	for (i = 0; i < config->n_autoboot_opts; i++) {
+		if (config->autoboot_opts[i].boot_type == BOOT_DEVICE_TYPE)
+			pb_log("  boot device %d: %s\n", i,
+			       device_type_name(config->autoboot_opts[i].type));
+		else
+			pb_log("  boot device %d: uuid: %s\n",
+			       i, config->autoboot_opts[i].uuid);
 	}
 
 	pb_log("  IPMI boot device 0x%02x%s\n", config->ipmi_bootdev,
@@ -109,17 +106,16 @@ void config_set_defaults(struct config *config)
 	config->network.n_interfaces = 0;
 	config->network.dns_servers = NULL;
 	config->network.n_dns_servers = 0;
-	config->boot_device = NULL;
 	config->safe_mode = false;
 	config->lang = NULL;
 
-	config->n_boot_priorities = 2;
-	config->boot_priorities = talloc_array(config, struct boot_priority,
-						config->n_boot_priorities);
-	config->boot_priorities[0].type = DEVICE_TYPE_NETWORK;
-	config->boot_priorities[0].priority = 0;
-	config->boot_priorities[1].type = DEVICE_TYPE_ANY;
-	config->boot_priorities[1].priority = 1;
+	config->n_autoboot_opts = 2;
+	config->autoboot_opts = talloc_array(config, struct autoboot_option,
+						config->n_autoboot_opts);
+	config->autoboot_opts[0].boot_type = BOOT_DEVICE_TYPE;
+	config->autoboot_opts[0].type = DEVICE_TYPE_NETWORK;
+	config->autoboot_opts[1].boot_type = BOOT_DEVICE_TYPE;
+	config->autoboot_opts[1].type = DEVICE_TYPE_ANY;
 
 	config->ipmi_bootdev = 0;
 	config->ipmi_bootdev_persistent = false;
diff --git a/lib/pb-config/pb-config.c b/lib/pb-config/pb-config.c
index a2272f4..98a6078 100644
--- a/lib/pb-config/pb-config.c
+++ b/lib/pb-config/pb-config.c
@@ -59,21 +59,21 @@ struct config *config_copy(void *ctx, const struct config *src)
 		dest->network.dns_servers[i] = talloc_strdup(dest,
 				src->network.dns_servers[i]);
 
-	dest->n_boot_priorities = src->n_boot_priorities;
-	dest->boot_priorities = talloc_array(dest, struct boot_priority,
-			src->n_boot_priorities);
-
-	for (i = 0; i < src->n_boot_priorities; i++) {
-		dest->boot_priorities[i].priority =
-					src->boot_priorities[i].priority;
-		dest->boot_priorities[i].type = src->boot_priorities[i].type;
+	dest->n_autoboot_opts = src->n_autoboot_opts;
+	dest->autoboot_opts = talloc_array(dest, struct autoboot_option,
+					dest->n_autoboot_opts);
+
+	for (i = 0; i < src->n_autoboot_opts; i++) {
+		dest->autoboot_opts[i].boot_type =
+			src->autoboot_opts[i].boot_type;
+		if (src->autoboot_opts[i].boot_type == BOOT_DEVICE_TYPE)
+			dest->autoboot_opts[i].type =
+				src->autoboot_opts[i].type;
+		else
+			dest->autoboot_opts[i].uuid =
+				talloc_strdup(dest, src->autoboot_opts[i].uuid);
 	}
 
-	if (src->boot_device && strlen(src->boot_device))
-		dest->boot_device = talloc_strdup(dest, src->boot_device);
-	else
-		dest->boot_device = NULL;
-
 	dest->ipmi_bootdev = src->ipmi_bootdev;
 	dest->ipmi_bootdev_persistent = src->ipmi_bootdev_persistent;
 
diff --git a/lib/pb-protocol/pb-protocol.c b/lib/pb-protocol/pb-protocol.c
index 4398248..69ea35d 100644
--- a/lib/pb-protocol/pb-protocol.c
+++ b/lib/pb-protocol/pb-protocol.c
@@ -280,9 +280,13 @@ int pb_protocol_config_len(const struct config *config)
 		len += 4 + optional_strlen(config->network.dns_servers[i]);
 
 	len += 4;
-	len += config->n_boot_priorities * 8;
-
-	len += 4 + optional_strlen(config->boot_device);
+	for (i = 0; i < config->n_autoboot_opts; i++) {
+		if (config->autoboot_opts[i].boot_type == BOOT_DEVICE_TYPE)
+			len += 4 + 4;
+		else
+			len += 4 + 4 +
+				optional_strlen(config->autoboot_opts[i].uuid);
+	}
 
 	len += 4 + 4; /* ipmi_bootdev, ipmi_bootdev_persistent */
 
@@ -477,19 +481,22 @@ int pb_protocol_serialise_config(const struct config *config,
 				config->network.dns_servers[i]);
 	}
 
-	*(uint32_t *)pos = __cpu_to_be32(config->n_boot_priorities);
+	*(uint32_t *)pos = __cpu_to_be32(config->n_autoboot_opts);
 	pos += 4;
-	for (i = 0; i < config->n_boot_priorities; i++) {
-		*(uint32_t *)pos =
-			__cpu_to_be32(config->boot_priorities[i].type);
-		pos += 4;
+	for (i = 0; i < config->n_autoboot_opts; i++) {
 		*(uint32_t *)pos =
-			__cpu_to_be32(config->boot_priorities[i].priority);
+			__cpu_to_be32(config->autoboot_opts[i].boot_type);
 		pos += 4;
+		if (config->autoboot_opts[i].boot_type == BOOT_DEVICE_TYPE) {
+			*(uint32_t *)pos =
+				__cpu_to_be32(config->autoboot_opts[i].type);
+			pos += 4;
+		} else {
+			pos += pb_protocol_serialise_string(pos,
+						config->autoboot_opts[i].uuid);
+		}
 	}
 
-	pos += pb_protocol_serialise_string(pos, config->boot_device);
-
 	*(uint32_t *)pos = __cpu_to_be32(config->ipmi_bootdev);
 	pos += 4;
 	*(uint32_t *)pos = config->ipmi_bootdev_persistent;
@@ -925,24 +932,26 @@ int pb_protocol_deserialise_config(struct config *config,
 		config->network.dns_servers[i] = str;
 	}
 
-	if (read_u32(&pos, &len, &config->n_boot_priorities))
+	if (read_u32(&pos, &len, &config->n_autoboot_opts))
 		goto out;
-	config->boot_priorities = talloc_array(config, struct boot_priority,
-			config->n_boot_priorities);
+	config->autoboot_opts = talloc_array(config, struct autoboot_option,
+			config->n_autoboot_opts);
 
-	for (i = 0; i < config->n_boot_priorities; i++) {
+	for (i = 0; i < config->n_autoboot_opts; i++) {
 		if (read_u32(&pos, &len, &tmp))
 			goto out;
-		config->boot_priorities[i].priority = (int)tmp;
-		if (read_u32(&pos, &len, &tmp))
-			goto out;
-		config->boot_priorities[i].type = tmp;
+		config->autoboot_opts[i].boot_type = (int)tmp;
+		if (config->autoboot_opts[i].boot_type == BOOT_DEVICE_TYPE) {
+			if (read_u32(&pos, &len, &tmp))
+				goto out;
+			config->autoboot_opts[i].type = tmp;
+		} else {
+			if (read_string(config, &pos, &len, &str))
+				goto out;
+			config->autoboot_opts[i].uuid = str;
+		}
 	}
 
-	if (read_string(config, &pos, &len, &str))
-		goto out;
-	config->boot_device = str;
-
 	if (read_u32(&pos, &len, &config->ipmi_bootdev))
 		goto out;
 	if (read_u32(&pos, &len, &tmp))
diff --git a/lib/types/types.h b/lib/types/types.h
index e22dbc3..3bb8c9b 100644
--- a/lib/types/types.h
+++ b/lib/types/types.h
@@ -113,15 +113,6 @@ struct network_config {
 	unsigned int		n_dns_servers;
 };
 
-struct boot_priority {
-	/* Boot options with higher priority values will take precedence over
-	 * lower values. Negative priorities signify "don't boot this by
-	 * default".
-	 */
-	int			priority;
-	enum device_type	type;
-};
-
 struct autoboot_option {
 	enum {
 		BOOT_DEVICE_TYPE,
@@ -138,10 +129,8 @@ struct config {
 	unsigned int		autoboot_timeout_sec;
 	struct network_config	network;
 
-	struct boot_priority	*boot_priorities;
-	unsigned int		n_boot_priorities;
-
-	char			*boot_device;
+	struct autoboot_option	*autoboot_opts;
+	unsigned int		n_autoboot_opts;
 
 	unsigned int		ipmi_bootdev;
 	bool			ipmi_bootdev_persistent;
diff --git a/ui/ncurses/nc-config.c b/ui/ncurses/nc-config.c
index c45df34..3156b9b 100644
--- a/ui/ncurses/nc-config.c
+++ b/ui/ncurses/nc-config.c
@@ -33,16 +33,10 @@
 #include "nc-config.h"
 #include "nc-widgets.h"
 
-#define N_FIELDS	26
+#define N_FIELDS	29
 
 extern struct help_text config_help_text;
 
-enum autoboot_type {
-	AUTOBOOT_ANY,
-	AUTOBOOT_ONE,
-	AUTOBOOT_DISABLED,
-};
-
 enum net_conf_type {
 	NET_CONF_TYPE_DHCP_ALL,
 	NET_CONF_TYPE_DHCP_ONE,
@@ -57,7 +51,9 @@ struct config_screen {
 
 	bool			exit;
 	bool			show_help;
+	bool			show_subset;
 	bool			need_redraw;
+
 	void			(*on_exit)(struct cui *);
 
 	int			scroll_y;
@@ -67,12 +63,16 @@ struct config_screen {
 	int			network_config_y;
 
 	enum net_conf_type	net_conf_type;
-	enum autoboot_type	autoboot_type;
+
+	bool			autoboot_enabled;
 
 	struct {
-		struct nc_widget_select		*autoboot_f;
-		struct nc_widget_label		*autoboot_l;
-		struct nc_widget_select		*boot_device_f;
+		struct nc_widget_label		*boot_order_l;
+		struct nc_widget_subset		*boot_order_f;
+		struct nc_widget_label		*boot_empty_l;
+		struct nc_widget_button		*boot_add_b;
+		struct nc_widget_button		*boot_none_b;
+		struct nc_widget_button		*boot_any_b;
 		struct nc_widget_textbox	*timeout_f;
 		struct nc_widget_label		*timeout_l;
 		struct nc_widget_label		*timeout_help_l;
@@ -151,7 +151,7 @@ static void config_screen_process_key(struct nc_scr *scr, int key)
 		cui_show_help(screen->cui, _("System Configuration"),
 				&config_help_text);
 
-	} else if (handled) {
+	} else if (handled && !screen->show_subset) {
 		pad_refresh(screen);
 	}
 }
@@ -165,6 +165,7 @@ static void config_screen_resize(struct nc_scr *scr)
 static int config_screen_post(struct nc_scr *scr)
 {
 	struct config_screen *screen = config_screen_from_scr(scr);
+	screen->show_subset = false;
 	widgetset_post(screen->widgetset);
 	nc_scr_frame_draw(scr);
 	if (screen->need_redraw) {
@@ -193,40 +194,48 @@ static int screen_process_form(struct config_screen *screen)
 	const struct system_info *sysinfo = screen->cui->sysinfo;
 	enum net_conf_type net_conf_type;
 	struct interface_config *iface;
-	char *str, *end, *uuid;
+	char *str, *end;
 	struct config *config;
-	int rc, idx;
+	int i, n_boot_opts, rc, idx;
+	unsigned int *order;
+	char mac[20];
 
 	config = config_copy(screen, screen->cui->config);
 
-	screen->autoboot_type =
-		widget_select_get_value(screen->widgets.autoboot_f);
-
-	config->autoboot_enabled = screen->autoboot_type != AUTOBOOT_DISABLED;
-
-	uuid = NULL;
-	if (screen->autoboot_type == AUTOBOOT_ONE) {
-		char mac[20];
-
-		/* if idx is -1 here, we have an unknown UUID selected.
-		 * Otherwise, it's a blockdev index (idx <= n_blockdevs) or an
-		 * interface index.
-		 */
-		idx = widget_select_get_value(screen->widgets.boot_device_f);
-		if (idx >= (int)sysinfo->n_blockdevs) {
-			struct interface_info *info = sysinfo->
-				interfaces[idx - sysinfo->n_blockdevs];
-			mac_str(info->hwaddr, info->hwaddr_size,
-					mac, sizeof(mac));
-			uuid = mac;
-		} else if (idx != -1) {
-			uuid = sysinfo->blockdevs[idx]->uuid;
+	talloc_free(config->autoboot_opts);
+	config->n_autoboot_opts = 0;
+
+	n_boot_opts = widget_subset_get_order(config, &order,
+					      screen->widgets.boot_order_f);
+
+	config->autoboot_enabled = n_boot_opts > 0;
+
+	config->n_autoboot_opts = n_boot_opts;
+	config->autoboot_opts = talloc_array(config, struct autoboot_option,
+					     n_boot_opts);
+
+	for (i = 0; i < n_boot_opts; i++) {
+		if (order[i] < sysinfo->n_blockdevs) {
+			/* disk uuid */
+			config->autoboot_opts[i].boot_type = BOOT_DEVICE_UUID;
+			config->autoboot_opts[i].uuid = talloc_strdup(config,
+							sysinfo->blockdevs[order[i]]->uuid);
+		} else if(order[i] < (sysinfo->n_blockdevs + sysinfo->n_interfaces)) {
+			/* net uuid */
+			order[i] -= sysinfo->n_blockdevs;
+			config->autoboot_opts[i].boot_type = BOOT_DEVICE_UUID;
+			mac_str(sysinfo->interfaces[order[i]]->hwaddr,
+				sysinfo->interfaces[order[i]]->hwaddr_size,
+				mac, sizeof(mac));
+			config->autoboot_opts[i].uuid = talloc_strdup(config, mac);
+		} else {
+			/* device type */
+			order[i] -= (sysinfo->n_blockdevs + sysinfo->n_interfaces);
+			config->autoboot_opts[i].boot_type = BOOT_DEVICE_TYPE;
+			config->autoboot_opts[i].type = order[i];
 		}
 	}
 
-	talloc_free(config->boot_device);
-	config->boot_device = uuid ? talloc_strdup(config, uuid) : NULL;
-
 	str = widget_textbox_get_value(screen->widgets.timeout_f);
 	if (str) {
 		unsigned long x;
@@ -367,35 +376,55 @@ static void config_screen_layout_widgets(struct config_screen *screen)
 	help_x = screen->field_x + 2 +
 		widget_width(widget_textbox_base(screen->widgets.dns_f));
 
-	y += layout_pair(screen, y, screen->widgets.autoboot_l,
-			widget_select_base(screen->widgets.autoboot_f));
+	y += 1;
+
+	wl = widget_label_base(screen->widgets.boot_order_l);
+	widget_set_visible(wl, true);
+	widget_move(wl, y, screen->label_x);
+
+	wf = widget_subset_base(screen->widgets.boot_order_f);
+	widget_move(wf, y, screen->field_x);
+	wl = widget_label_base(screen->widgets.boot_empty_l);
+	widget_move(wl, y, screen->field_x);
 
-	wf = widget_select_base(screen->widgets.boot_device_f);
-	if (screen->autoboot_type == AUTOBOOT_ONE) {
+	if (widget_subset_height(screen->widgets.boot_order_f)) {
 		widget_set_visible(wf, true);
-		widget_move(wf, y, screen->field_x + 3);
+		widget_set_visible(wl, false);
 		y += widget_height(wf);
 	} else {
+		widget_set_visible(wl, true);
 		widget_set_visible(wf, false);
+		y += 1;
 	}
 
 	y += 1;
 
+	widget_move(widget_button_base(screen->widgets.boot_add_b),
+			y, screen->field_x);
+	widget_move(widget_button_base(screen->widgets.boot_any_b),
+			y, screen->field_x + 12);
+	widget_move(widget_button_base(screen->widgets.boot_none_b),
+			y, screen->field_x + 30);
+
+	wf = widget_button_base(screen->widgets.boot_add_b);
+	if (widget_subset_n_inactive(screen->widgets.boot_order_f))
+		widget_set_visible(wf, true);
+	else
+		widget_set_visible(wf, false);
+
+	y += 2;
+
 	wf = widget_textbox_base(screen->widgets.timeout_f);
 	wl = widget_label_base(screen->widgets.timeout_l);
 	wh = widget_label_base(screen->widgets.timeout_help_l);
-	if (screen->autoboot_type != AUTOBOOT_DISABLED) {
-		widget_set_visible(wl, true);
-		widget_set_visible(wf, true);
-		widget_set_visible(wh, true);
+	widget_set_visible(wl, screen->autoboot_enabled);
+	widget_set_visible(wf, screen->autoboot_enabled);
+	if (screen->autoboot_enabled) {
+		widget_set_visible(wh, screen->autoboot_enabled);
 		widget_move(wl, y, screen->label_x);
 		widget_move(wf, y, screen->field_x);
 		widget_move(wh, y, screen->field_x + widget_width(wf) + 1);
 		y += 2;
-	} else {
-		widget_set_visible(wl, false);
-		widget_set_visible(wf, false);
-		widget_set_visible(wh, false);
 	}
 
 	y += layout_pair(screen, y, screen->widgets.network_l,
@@ -500,15 +529,69 @@ static void config_screen_network_change(void *arg, int value)
 	widgetset_post(screen->widgetset);
 }
 
-static void config_screen_autoboot_change(void *arg, int value)
+static void config_screen_boot_order_change(void *arg, int value)
+{
+	(void)value;
+	struct config_screen *screen = arg;
+	widgetset_unpost(screen->widgetset);
+	config_screen_layout_widgets(screen);
+	widgetset_post(screen->widgetset);
+}
+
+static void config_screen_add_device(void *arg)
 {
 	struct config_screen *screen = arg;
-	screen->autoboot_type = value;
+
+	screen->show_subset = true;
+	cui_show_subset(screen->cui, _("Select an option"),
+			screen->widgets.boot_order_f);
+}
+
+static void config_screen_autoboot_none(void *arg)
+{
+	struct config_screen *screen = arg;
+	struct nc_widget_subset *subset = screen->widgets.boot_order_f;
+
+	widget_subset_clear_active(subset);
+	screen->autoboot_enabled = false;
+
 	widgetset_unpost(screen->widgetset);
 	config_screen_layout_widgets(screen);
 	widgetset_post(screen->widgetset);
 }
 
+static void config_screen_autoboot_any(void *arg)
+{
+	struct config_screen *screen = arg;
+	const struct system_info *sysinfo = screen->cui->sysinfo;
+	struct nc_widget_subset *subset = screen->widgets.boot_order_f;
+	int idx;
+
+	widget_subset_clear_active(subset);
+
+	idx = sysinfo->n_blockdevs + sysinfo->n_interfaces + DEVICE_TYPE_ANY;
+
+	widget_subset_make_active(screen->widgets.boot_order_f, idx);
+
+	screen->autoboot_enabled = true;
+
+	widgetset_unpost(screen->widgetset);
+	config_screen_layout_widgets(screen);
+	widgetset_post(screen->widgetset);
+}
+
+static void config_screen_update_subset(void *arg,
+			struct nc_widget_subset *subset, int idx)
+{
+	struct config_screen *screen = arg;
+
+	if (idx >= 0)
+		widget_subset_make_active(subset, idx);
+	if (!screen->autoboot_enabled)
+		screen->autoboot_enabled = true;
+	config_screen_layout_widgets(screen);
+}
+
 static struct interface_config *first_active_interface(
 		const struct config *config)
 {
@@ -550,6 +633,31 @@ static void config_screen_setup_empty(struct config_screen *screen)
 			cancel_click, screen);
 }
 
+static int find_autoboot_idx(const struct system_info *sysinfo,
+		struct autoboot_option *opt)
+{
+	unsigned int i;
+
+	if (opt->boot_type == BOOT_DEVICE_TYPE)
+		return sysinfo->n_blockdevs + sysinfo->n_interfaces + opt->type;
+
+	for (i = 0; i < sysinfo->n_blockdevs; i++) {
+		if (!strcmp(sysinfo->blockdevs[i]->uuid, opt->uuid))
+			return i;
+	}
+
+	for (i = 0; i < sysinfo->n_interfaces; i++) {
+		struct interface_info *info = sysinfo->interfaces[i];
+		char mac[20];
+
+		mac_str(info->hwaddr, info->hwaddr_size, mac, sizeof(mac));
+
+		if (!strcmp(mac, opt->uuid))
+			return sysinfo->n_blockdevs + i;
+	}
+
+	return -1;
+}
 
 static void config_screen_setup_widgets(struct config_screen *screen,
 		const struct config *config,
@@ -560,7 +668,6 @@ static void config_screen_setup_widgets(struct config_screen *screen,
 	char *str, *ip, *mask, *gw;
 	enum net_conf_type type;
 	unsigned int i;
-	bool found;
 
 	build_assert(sizeof(screen->widgets) / sizeof(struct widget *)
 			== N_FIELDS);
@@ -568,81 +675,84 @@ static void config_screen_setup_widgets(struct config_screen *screen,
 	type = screen->net_conf_type;
 	ifcfg = first_active_interface(config);
 
-	screen->widgets.autoboot_l = widget_new_label(set, 0, 0,
-					_("Autoboot:"));
-	screen->widgets.autoboot_f = widget_new_select(set, 0, 0, 55);
-
-	widget_select_on_change(screen->widgets.autoboot_f,
-			config_screen_autoboot_change, screen);
-
-	screen->widgets.boot_device_f = widget_new_select(set, 0, 0, 55);
-
-	widget_select_add_option(screen->widgets.autoboot_f,
-					AUTOBOOT_DISABLED,
-					_("Don't autoboot"),
-					screen->autoboot_type ==
-						AUTOBOOT_DISABLED);
-	widget_select_add_option(screen->widgets.autoboot_f,
-					AUTOBOOT_ANY,
-					_("Autoboot from any "
-						"disk/network device"),
-					screen->autoboot_type ==
-						AUTOBOOT_ANY);
-	widget_select_add_option(screen->widgets.autoboot_f,
-					AUTOBOOT_ONE,
-					_("Only autoboot from a specific "
-						"disk/network device"),
-					screen->autoboot_type ==
-						AUTOBOOT_ONE);
-
-	found = false;
+	screen->widgets.boot_add_b = widget_new_button(set, 0, 0, 10,
+					_("Add Device"), config_screen_add_device,
+					screen);
+
+	screen->widgets.boot_none_b = widget_new_button(set, 0, 0, 10,
+					_("Clear"),
+					config_screen_autoboot_none, screen);
+
+	screen->widgets.boot_any_b = widget_new_button(set, 0, 0, 16,
+					_("Clear & Boot Any"), config_screen_autoboot_any,
+					screen);
+
+	screen->widgets.boot_order_l = widget_new_label(set, 0, 0,
+					_("Boot order:"));
+	screen->widgets.boot_order_f = widget_new_subset(set, 0, 0,
+					COLS - screen->field_x,
+					config_screen_update_subset);
+	screen->widgets.boot_empty_l = widget_new_label(set, 0, 0,
+					_("(None)"));
+
+	widget_subset_on_change(screen->widgets.boot_order_f,
+			config_screen_boot_order_change, screen);
 
 	for (i = 0; i < sysinfo->n_blockdevs; i++) {
 		struct blockdev_info *bd = sysinfo->blockdevs[i];
-		bool selected;
 		char *label;
 
-		selected = config->boot_device &&
-				!strcmp(config->boot_device, bd->uuid);
-		if (selected)
-			found = true;
-
 		label = talloc_asprintf(screen, _("disk: %s [uuid: %s]"),
 				bd->name, bd->uuid);
 
-		widget_select_add_option(screen->widgets.boot_device_f, i,
-					label, selected);
+		widget_subset_add_option(screen->widgets.boot_order_f, label);
 	}
 
 	for (i = 0; i < sysinfo->n_interfaces; i++) {
 		struct interface_info *info = sysinfo->interfaces[i];
 		char *label, mac[20];
-		bool selected;
 
 		mac_str(info->hwaddr, info->hwaddr_size, mac, sizeof(mac));
-		selected = config->boot_device &&
-				!strcmp(config->boot_device, mac);
-		if (selected)
-			found = true;
 
 		label = talloc_asprintf(screen, _("net:  %s [mac: %s]"),
 				info->name, mac);
 
-		widget_select_add_option(screen->widgets.boot_device_f,
-						i + sysinfo->n_blockdevs,
-						label, selected);
+		widget_subset_add_option(screen->widgets.boot_order_f, label);
 	}
 
-	if (screen->autoboot_type == AUTOBOOT_ONE && !found) {
+	for (i = DEVICE_TYPE_NETWORK; i < DEVICE_TYPE_NETWORK + 4; i++) {
 		char *label;
 
-		label = talloc_asprintf(screen, _("Unknown UUID: %s"),
-				config->boot_device);
+		if (i == DEVICE_TYPE_ANY)
+			label = talloc_asprintf(screen, _("Any Device"));
+		else
+			label = talloc_asprintf(screen, _("Any %s device"),
+						device_type_display_name(i));
 
-		widget_select_add_option(screen->widgets.boot_device_f, -1,
-						label, true);
+		widget_subset_add_option(screen->widgets.boot_order_f, label);
 	}
 
+	screen->autoboot_enabled = config->n_autoboot_opts;
+	for (i = 0; i < config->n_autoboot_opts; i++) {
+		struct autoboot_option *opt = &config->autoboot_opts[i];
+		int idx;
+
+		idx = find_autoboot_idx(sysinfo, opt);
+
+		if (idx >= 0) {
+			widget_subset_make_active(screen->widgets.boot_order_f,
+						  idx);
+		} else {
+			if (opt->boot_type == BOOT_DEVICE_TYPE)
+				pb_log("%s: Unknown autoboot option: %d\n",
+				       __func__, opt->type);
+			else
+				pb_log("%s: Unknown autoboot UUID: %s\n",
+				       __func__, opt->uuid);
+		}
+	}
+
+
 	str = talloc_asprintf(screen, "%d", config->autoboot_timeout_sec);
 	screen->widgets.timeout_l = widget_new_label(set, 0, 0, _("Timeout:"));
 	screen->widgets.timeout_f = widget_new_textbox(set, 0, 0, 5, str);
@@ -818,12 +928,6 @@ static void config_screen_draw(struct config_screen *screen,
 		config_screen_setup_empty(screen);
 	} else {
 		screen->net_conf_type = find_net_conf_type(config);
-		if (!config->autoboot_enabled)
-			screen->autoboot_type = AUTOBOOT_DISABLED;
-		else
-			screen->autoboot_type = config->boot_device ?
-					AUTOBOOT_ONE : AUTOBOOT_ANY;
-
 		config_screen_setup_widgets(screen, config, sysinfo);
 		config_screen_layout_widgets(screen);
 	}
@@ -868,6 +972,8 @@ struct config_screen *config_screen_init(struct cui *cui,
 	screen->label_x = 2;
 	screen->field_x = 17;
 
+	screen->show_subset = false;
+
 	screen->scr.frame.ltitle = talloc_strdup(screen,
 			_("Petitboot System Configuration"));
 	screen->scr.frame.rtitle = NULL;
diff --git a/utils/pb-config.c b/utils/pb-config.c
index 3bd670c..009bec7 100644
--- a/utils/pb-config.c
+++ b/utils/pb-config.c
@@ -61,7 +61,16 @@ static void print_one_config(void *ctx, const char *req, const char *name,
 
 static void print_config(void *ctx, struct config *config, const char *var)
 {
-	print_one_config(ctx, var, "bootdev", "%s", config->boot_device);
+	unsigned int i;
+
+	for (i = 0; i < config->n_autoboot_opts; i++) {
+		if (config->autoboot_opts[i].boot_type == BOOT_DEVICE_TYPE)
+			print_one_config(ctx, var, "bootdev", "%s",
+			 device_type_name(config->autoboot_opts[i].type));
+		else
+			print_one_config(ctx, var, "bootdev", "%s",
+					 config->autoboot_opts[i].uuid);
+	}
 	print_one_config(ctx, var, "autoboot", "%s",
 			config->autoboot_enabled ? "enabled" : "disabled");
 	print_one_config(ctx, var, "timeout", "%d",