From: Jeremy Kerr <jk@ozlabs.org>
Date: Mon, 21 Jul 2014 10:18:35 +0000 (+0800)
Subject: discover: Add safe mode
X-Git-Tag: v1.0.0~155
X-Git-Url: http://git.ozlabs.org/?p=petitboot;a=commitdiff_plain;h=d2b12ddb905a74fa6b2e454142b0b9f71fd99398

discover: Add safe mode

Safe mode configures the discover server to not start any device
parsing; this can be used to diagnose any problems with early device
handing.

In safe mode, we don't initialise any of the device sources - udev,
network and user events are disabled.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
---

diff --git a/discover/device-handler.c b/discover/device-handler.c
index b93cdfa..e4978fa 100644
--- a/discover/device-handler.c
+++ b/discover/device-handler.c
@@ -285,6 +285,9 @@ struct device_handler *device_handler_init(struct discover_server *server,
 
 	parser_init();
 
+	if (config_get()->safe_mode)
+		return handler;
+
 	rc = device_handler_init_sources(handler);
 	if (rc) {
 		talloc_free(handler);
@@ -842,6 +845,13 @@ static int device_handler_init_sources(struct device_handler *handler)
 
 static void device_handler_reinit_sources(struct device_handler *handler)
 {
+	/* if we haven't initialised sources previously (becuase we started in
+	 * safe mode), then init once here. */
+	if (!(handler->udev || handler->network || handler->user_event)) {
+		device_handler_init_sources(handler);
+		return;
+	}
+
 	udev_reinit(handler->udev);
 
 	network_shutdown(handler->network);
diff --git a/discover/platform.c b/discover/platform.c
index 3ab6b7b..be60f00 100644
--- a/discover/platform.c
+++ b/discover/platform.c
@@ -43,6 +43,9 @@ static void dump_config(struct config *config)
 	if (config->network.n_interfaces || config->network.n_dns_servers)
 		pb_log(" network configuration:\n");
 
+	if (config->safe_mode)
+		pb_log(" safe mode: active\n");
+
 	for (i = 0; i < config->network.n_interfaces; i++) {
 		struct interface_config *ifconf =
 			config->network.interfaces[i];
diff --git a/lib/pb-config/pb-config.c b/lib/pb-config/pb-config.c
index 2adc7b2..d43a5ab 100644
--- a/lib/pb-config/pb-config.c
+++ b/lib/pb-config/pb-config.c
@@ -42,6 +42,7 @@ struct config *config_copy(void *ctx, const struct config *src)
 	dest = talloc(ctx, struct config);
 	dest->autoboot_enabled = src->autoboot_enabled;
 	dest->autoboot_timeout_sec = src->autoboot_timeout_sec;
+	dest->safe_mode = src->safe_mode;
 
 	dest->network.n_interfaces = src->network.n_interfaces;
 	dest->network.interfaces = talloc_array(dest, struct interface_config *,
diff --git a/lib/pb-protocol/pb-protocol.c b/lib/pb-protocol/pb-protocol.c
index 67e1f9e..d39c1c4 100644
--- a/lib/pb-protocol/pb-protocol.c
+++ b/lib/pb-protocol/pb-protocol.c
@@ -267,7 +267,8 @@ int pb_protocol_config_len(const struct config *config)
 	unsigned int i, len;
 
 	len =	4 /* config->autoboot_enabled */ +
-		4 /* config->autoboot_timeout_sec */;
+		4 /* config->autoboot_timeout_sec */ +
+		4 /* config->safe_mode */;
 
 	len += 4;
 	for (i = 0; i < config->network.n_interfaces; i++)
@@ -448,6 +449,9 @@ int pb_protocol_serialise_config(const struct config *config,
 	*(uint32_t *)pos = __cpu_to_be32(config->autoboot_timeout_sec);
 	pos += 4;
 
+	*(uint32_t *)pos = config->safe_mode;
+	pos += 4;
+
 	*(uint32_t *)pos = __cpu_to_be32(config->network.n_interfaces);
 	pos += 4;
 	for (i = 0; i < config->network.n_interfaces; i++) {
@@ -862,6 +866,10 @@ int pb_protocol_deserialise_config(struct config *config,
 	if (read_u32(&pos, &len, &config->autoboot_timeout_sec))
 		goto out;
 
+	if (read_u32(&pos, &len, &tmp))
+		goto out;
+	config->safe_mode = !!tmp;
+
 	if (read_u32(&pos, &len, &config->network.n_interfaces))
 		goto out;
 
diff --git a/lib/types/types.h b/lib/types/types.h
index 762530a..0333a02 100644
--- a/lib/types/types.h
+++ b/lib/types/types.h
@@ -121,6 +121,7 @@ struct boot_priority {
 struct config {
 	bool			autoboot_enabled;
 	unsigned int		autoboot_timeout_sec;
+	bool			safe_mode;
 	struct network_config	network;
 	struct boot_priority	*boot_priorities;
 	unsigned int		n_boot_priorities;