Merge "ueventd: track platform device uevents to parse block device names" (ab0c4e03) · Commits · e / os / android_system_core

init/devices.c

+88 −10

Original line number	Diff line number	Diff line
		@@ -97,8 +97,15 @@ struct perm_node {
		struct listnode plist;
		};

		struct platform_node {
		char *name;
		int name_len;
		struct listnode list;
		};

		static list_declare(sys_perms);
		static list_declare(dev_perms);
		static list_declare(platform_names);

		int add_dev_perms(const char name, const char attr,
		mode_t perm, unsigned int uid, unsigned int gid,
		@@ -212,6 +219,68 @@ static void make_device(const char *path,
		setegid(AID_ROOT);
		}

		static void add_platform_device(const char *name)
		{
		int name_len = strlen(name);
		struct listnode *node;
		struct platform_node *bus;

		list_for_each_reverse(node, &platform_names) {
		bus = node_to_item(node, struct platform_node, list);
		if ((bus->name_len < name_len) &&
		(name[bus->name_len] == '/') &&
		!strncmp(name, bus->name, bus->name_len))
		/* subdevice of an existing platform, ignore it */
		return;
		}

		INFO("adding platform device %s\n", name);

		bus = calloc(1, sizeof(struct platform_node));
		bus->name = strdup(name);
		bus->name_len = name_len;
		list_add_tail(&platform_names, &bus->list);
		}

		/*
		* given a name that may start with a platform device, find the length of the
		* platform device prefix. If it doesn't start with a platform device, return
		* 0.
		*/
		static const char find_platform_device(const char name)
		{
		int name_len = strlen(name);
		struct listnode *node;
		struct platform_node *bus;

		list_for_each_reverse(node, &platform_names) {
		bus = node_to_item(node, struct platform_node, list);
		if ((bus->name_len < name_len) &&
		(name[bus->name_len] == '/') &&
		!strncmp(name, bus->name, bus->name_len))
		return bus->name;
		}

		return NULL;
		}

		static void remove_platform_device(const char *name)
		{
		struct listnode *node;
		struct platform_node *bus;

		list_for_each_reverse(node, &platform_names) {
		bus = node_to_item(node, struct platform_node, list);
		if (!strcmp(name, bus->name)) {
		INFO("removing platform device %s\n", name);
		free(bus->name);
		list_remove(node);
		free(bus);
		return;
		}
		}
		}

		#if LOG_UEVENTS

		static inline suseconds_t get_usecs(void)
		@@ -332,7 +401,7 @@ err:

		static char *parse_platform_block_device(struct uevent uevent)
		{
		const char *driver;
		const char *device;
		const char *path;
		char *slash;
		int width;
		@@ -352,16 +421,14 @@ static char *parse_platform_block_device(struct uevent uevent)

		/* Drop "/devices/platform/" */
		path = uevent->path;
		driver = path + 18;
		slash = strchr(driver, '/');
		if (!slash)
		goto err;
		width = slash - driver;
		if (width <= 0)
		device = path + 18;
		device = find_platform_device(device);
		if (!device)
		goto err;

		snprintf(link_path, sizeof(link_path), "/dev/block/platform/%.*s",
		width, driver);
		INFO("found platform device %s\n", device);

		snprintf(link_path, sizeof(link_path), "/dev/block/platform/%s", device);

		if (uevent->partition_name) {
		p = strdup(uevent->partition_name);
		@@ -421,6 +488,16 @@ static void handle_device(const char action, const char devpath,
		}
		}

		static void handle_platform_device_event(struct uevent *uevent)
		{
		const char name = uevent->path + 18; / length of /devices/platform/ */

		if (!strcmp(uevent->action, "add"))
		add_platform_device(name);
		else if (!strcmp(uevent->action, "remove"))
		remove_platform_device(name);
		}

		static const char parse_device_name(struct uevent uevent, unsigned int len)
		{
		const char *name;
		@@ -461,7 +538,6 @@ static void handle_block_device_event(struct uevent *uevent)

		handle_device(uevent->action, devpath, uevent->path, 1,
		uevent->major, uevent->minor, links);

		}

		static void handle_generic_device_event(struct uevent *uevent)
		@@ -537,6 +613,8 @@ static void handle_device_event(struct uevent *uevent)

		if (!strncmp(uevent->subsystem, "block", 5)) {
		handle_block_device_event(uevent);
		} else if (!strncmp(uevent->subsystem, "platform", 8)) {
		handle_platform_device_event(uevent);
		} else {
		handle_generic_device_event(uevent);
		}