X-Git-Url: http://git.ozlabs.org/?p=petitboot;a=blobdiff_plain;f=discover%2Fudev.c;h=537ef10263fa11193f03057d0335de48910abc0a;hp=b93c1a5f0ff6d68dace1c0cf8605c528dd11f3c2;hb=e6ba022cef0ab01bcfbd5ce2e0e3f93f6ee3376b;hpb=a7908ed63584ff12653b37fb2c2548c52c8ed9da

diff --git a/discover/udev.c b/discover/udev.c
index b93c1a5..537ef10 100644
--- a/discover/udev.c
+++ b/discover/udev.c
@@ -1,214 +1,505 @@
 
-#define _GNU_SOURCE
+#if defined(HAVE_CONFIG_H)
+#include "config.h"
+#endif
 
-#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <libudev.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
-#include <errno.h>
-#include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/types.h>
 #include <sys/un.h>
 
+#include <log/log.h>
+#include <types/types.h>
 #include <talloc/talloc.h>
 #include <waiter/waiter.h>
-#include <log/log.h>
+#include <system/system.h>
 
+#include "event.h"
 #include "udev.h"
 #include "pb-discover.h"
 #include "device-handler.h"
+#include "cdrom.h"
+#include "devmapper.h"
 
-#define PBOOT_DEVICE_SOCKET "/tmp/petitboot.udev"
+/* We set a default monitor buffer size, as we may not process monitor
+ * events while performing device discvoery. systemd uses a 128M buffer, so
+ * we'll do the same here */
+static const int monitor_bufsize = 128 * 1024 * 1024;
 
-#define max(a, b) ((a) > (b) ? (a) : (b))
-
-struct udev {
+struct pb_udev {
+	struct udev *udev;
+	struct udev_monitor *monitor;
 	struct device_handler *handler;
-	int socket;
 };
 
-static void parse_event_params(struct udev_event *event, char *buf, int len)
+static int udev_destructor(void *p)
 {
-	int param_len, name_len, value_len;
-	struct param *param;
-	char *sep;
-
-	for (; len > 0; len -= param_len + 1, buf += param_len + 1) {
-
-		/* find the length of the whole parameter */
-		param_len = strnlen(buf, len);
-		if (!param_len) {
-			/* multiple NULs? skip over */
-			param_len = 1;
-			continue;
-		}
-
-		/* find the separator */
-		sep = memchr(buf, '=', param_len);
-		if (!sep)
-			continue;
+	struct pb_udev *udev = p;
 
-		name_len = sep - buf;
-		value_len = param_len - name_len - 1;
-
-		/* update the params array */
-		event->params = talloc_realloc(event, event->params,
-					struct param, ++event->n_params);
-		param = &event->params[event->n_params - 1];
+	if (udev->monitor) {
+		udev_monitor_unref(udev->monitor);
+		udev->monitor = NULL;
+	}
 
-		param->name = talloc_strndup(event, buf, name_len);
-		param->value = talloc_strndup(event, sep + 1, value_len);
+	if (udev->udev) {
+		udev_unref(udev->udev);
+		udev->udev = NULL;
 	}
+
+	return 0;
 }
 
-const char *udev_event_param(struct udev_event *event, const char *name)
+static void udev_setup_device_params(struct udev_device *udev,
+		struct discover_device *dev)
 {
-	int i;
+	struct udev_list_entry *list, *entry;
 
-	for (i = 0; i < event->n_params; i++)
-		if (!strcasecmp(event->params[i].name, name))
-			return event->params[i].value;
+	list = udev_device_get_properties_list_entry(udev);
+	if (!list)
+		return;
 
-	return NULL;
+	udev_list_entry_foreach(entry, list)
+		discover_device_set_param(dev,
+				udev_list_entry_get_name(entry),
+				udev_list_entry_get_value(entry));
 }
 
-static void print_event(struct udev_event *event)
+static int udev_handle_block_add(struct pb_udev *udev, struct udev_device *dev,
+		const char *name)
 {
-	const char *action, *params[] = {
-		"DEVNAME", "ID_TYPE", "ID_BUS", "ID_FS_UUID", "ID_FS_LABEL",
+	struct discover_device *ddev;
+	unsigned int i = 0;
+	const char *typestr;
+	const char *uuid;
+	const char *path;
+	const char *node;
+	const char *prop;
+	const char *type;
+	const char *devname;
+	const char *ignored_types[] = {
+		"linux_raid_member",
+		"swap",
+		"LVM2_member",
 		NULL,
 	};
-	int i;
+	bool cdrom, usb;
 
-	action = event->action == UDEV_ACTION_ADD ? "add" : "remove";
+	typestr = udev_device_get_devtype(dev);
+	if (!typestr) {
+		pb_debug("udev_device_get_devtype failed\n");
+		return -1;
+	}
 
-	pb_log("udev %s event:\n", action);
-	pb_log("\tdevice: %s\n", event->device);
+	if (!(!strcmp(typestr, "disk") || !strcmp(typestr, "partition"))) {
+		pb_log("SKIP %s: invalid type %s\n", name, typestr);
+		return 0;
+	}
 
-	for (i = 0; params[i]; i++)
-		pb_log("\t%-12s => %s\n",
-				params[i], udev_event_param(event, params[i]));
+	node = udev_device_get_devnode(dev);
+	path = udev_device_get_devpath(dev);
+	if (path && strstr(path, "virtual/block/loop")) {
+		pb_log("SKIP: %s: ignored (path=%s)\n", name, path);
+		return 0;
+	}
 
-}
+	if (path && strstr(path, "virtual/block/ram")) {
+		device_handler_add_ramdisk(udev->handler, node);
+		return 0;
+	}
 
-static void handle_udev_message(struct udev *udev, char *buf, int len)
-{
-	char *sep, *device;
-	enum udev_action action;
-	struct udev_event *event;
-	int device_len;
-
-	/* we should see an <action>@<device>\0 at the head of the buffer */
-	sep = strchr(buf, '@');
-	if (!sep)
-		return;
+	cdrom = node && !!udev_device_get_property_value(dev, "ID_CDROM");
+	if (cdrom) {
+		/* CDROMs require a little initialisation, to get
+		 * petitboot-compatible tray behaviour */
+		cdrom_init(node);
+		if (!cdrom_media_present(node)) {
+			pb_log("SKIP: %s: no media present\n", name);
+			return 0;
+		}
+	}
 
-	/* terminate the action string */
-	*sep = '\0';
-	len -= sep - buf + 1;
+	/* If our environment's udev can recognise them explictly skip any
+	 * device mapper devices we encounter */
+	devname = udev_device_get_property_value(dev, "DM_NAME");
+	if (devname) {
+		pb_debug("SKIP: dm-device %s\n", devname);
+		return 0;
+	}
 
-	if (!strcmp(buf, "add")) {
-		action = UDEV_ACTION_ADD;
+	type = udev_device_get_property_value(dev, "ID_FS_TYPE");
+	if (!type) {
+		pb_log("SKIP: %s: no ID_FS_TYPE property\n", name);
+		return 0;
+	}
 
-	} else if (!strcmp(buf, "remove")) {
-		action = UDEV_ACTION_REMOVE;
+	while (ignored_types[i]) {
+		if (!strncmp(type, ignored_types[i], strlen(ignored_types[i]))) {
+			pb_log("SKIP: %s: ignore '%s' filesystem\n", name, type);
+			return 0;
+		}
+		i++;
+	}
 
-	} else {
-		return;
+	/* We may see multipath devices; they'll have the same uuid as an
+	 * existing device, so only parse the first. */
+	uuid = udev_device_get_property_value(dev, "ID_FS_UUID");
+	if (uuid) {
+		ddev = device_lookup_by_uuid(udev->handler, uuid);
+		if (ddev) {
+			pb_log("SKIP: %s UUID [%s] already present (as %s)\n",
+					name, uuid, ddev->device->id);
+			return 0;
+		}
 	}
 
-	/* initialise the device string */
-	device = sep + 1;
-	device_len = strnlen(device, len);
-	if (!device_len)
-		return;
+	ddev = discover_device_create(udev->handler, name);
+
+	ddev->device_path = talloc_strdup(ddev, node);
 
-	/* now we have an action and a device, we can construct an event */
-	event = talloc(udev, struct udev_event);
-	event->action = action;
-	event->device = talloc_strndup(event, device, device_len);
-	event->n_params = 0;
-	event->params = NULL;
+	if (uuid)
+		ddev->uuid = talloc_strdup(ddev, uuid);
+	prop = udev_device_get_property_value(dev, "ID_FS_LABEL");
+	if (prop)
+		ddev->label = talloc_strdup(ddev, prop);
 
-	len -= device_len + 1;
-	parse_event_params(event, device + device_len + 1, len);
+	usb = !!udev_device_get_property_value(dev, "ID_USB_DRIVER");
+	if (cdrom)
+		ddev->device->type = DEVICE_TYPE_OPTICAL;
+	else
+		ddev->device->type = usb ? DEVICE_TYPE_USB : DEVICE_TYPE_DISK;
 
-	print_event(event);
+	udev_setup_device_params(dev, ddev);
 
-	device_handler_event(udev->handler, event);
+	/* Create a snapshot for all disks, unless it is an assembled RAID array */
+	if ((ddev->device->type == DEVICE_TYPE_DISK ||
+	     ddev->device->type == DEVICE_TYPE_USB) &&
+	    !udev_device_get_property_value(dev, "MD_LEVEL"))
+		devmapper_init_snapshot(udev->handler, ddev);
 
-	talloc_free(event);
+	device_handler_discover(udev->handler, ddev);
 
-	return;
+	return 0;
 }
 
-static int udev_process(void *arg)
+static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev)
 {
-	struct udev *udev = arg;
-	char buf[4096];
-	int len;
+	const char *subsys;
+	const char *name;
+
+	name = udev_device_get_sysname(dev);
+	if (!name) {
+		pb_debug("udev_device_get_sysname failed\n");
+		return -1;
+	}
+
+	subsys = udev_device_get_subsystem(dev);
+	if (!subsys) {
+		pb_debug("udev_device_get_subsystem failed\n");
+		return -1;
+	}
+
+	if (device_lookup_by_id(udev->handler, name)) {
+		pb_debug("device %s is already present?\n", name);
+		return -1;
+	}
+
+	if (!strcmp(subsys, "block")) {
+		return udev_handle_block_add(udev, dev, name);
+	}
+
+	pb_log("SKIP %s: unknown subsystem %s\n", name, subsys);
+	return -1;
+}
+
 
-	len = recvfrom(udev->socket, buf, sizeof(buf), 0, NULL, NULL);
+static int udev_handle_dev_remove(struct pb_udev *udev, struct udev_device *dev)
+{
+	struct discover_device *ddev;
+	const char *name;
 
-	if (len < 0) {
-		pb_log("udev socket read failed: %s", strerror(errno));
+	name = udev_device_get_sysname(dev);
+	if (!name) {
+		pb_debug("udev_device_get_sysname failed\n");
 		return -1;
 	}
 
-	if (len == 0)
+	ddev = device_lookup_by_id(udev->handler, name);
+	if (!ddev)
 		return 0;
 
-	handle_udev_message(udev, buf, len);
+	device_handler_remove(udev->handler, ddev);
 
 	return 0;
 }
 
-static int udev_destructor(void *p)
+/* returns true if further event processing should stop (eg., we've
+ * ejected the cdrom)
+ */
+static bool udev_handle_cdrom_events(struct pb_udev *udev,
+		struct udev_device *dev, struct discover_device *ddev)
+{
+	const char *node;
+	bool eject = false;
+
+	node = udev_device_get_devnode(dev);
+
+	/* handle CDROM eject requests */
+	if (udev_device_get_property_value(dev, "DISK_EJECT_REQUEST")) {
+		pb_debug("udev: eject request\n");
+
+		/* If the device is mounted, cdrom_id's own eject request may
+		 * have failed. So, we'll need to do our own here.
+		 */
+		if (ddev) {
+			eject = ddev->mounted;
+			udev_handle_dev_remove(udev, dev);
+		}
+
+		if (eject)
+			cdrom_eject(node);
+
+		return true;
+	}
+
+	if (udev_device_get_property_value(dev, "DISK_MEDIA_CHANGE")) {
+		if (cdrom_media_present(node))
+			udev_handle_dev_add(udev, dev);
+		else
+			udev_handle_dev_remove(udev, dev);
+		return true;
+	}
+
+	return false;
+}
+
+static int udev_handle_dev_change(struct pb_udev *udev, struct udev_device *dev)
+{
+	struct discover_device *ddev;
+	const char *name;
+	int rc = 0;
+
+	name = udev_device_get_sysname(dev);
+
+	ddev = device_lookup_by_id(udev->handler, name);
+
+	/* if this is a CDROM device, process eject & media change requests;
+	 * these may stop further processing */
+	if (!udev_device_get_property_value(dev, "ID_CDROM")) {
+		if (udev_handle_cdrom_events(udev, dev, ddev))
+			return 0;
+	}
+
+	/* if this is a new device, treat it as an add */
+	if (!ddev)
+		rc = udev_handle_dev_add(udev, dev);
+
+	return rc;
+}
+
+static int udev_handle_dev_action(struct udev_device *dev, const char *action)
 {
-	struct udev *udev = p;
+	struct pb_udev *udev = udev_get_userdata(udev_device_get_udev(dev));
+	struct udev_list_entry *list;
+	const char *name;
+
+	list = udev_device_get_properties_list_entry(dev);
+	name = udev_device_get_sysname(dev);
+
+	pb_debug("udev: action %s, device %s\n", action, name);
+	pb_debug("udev: properties:\n");
+
+	for (; list; list = udev_list_entry_get_next(list))
+		pb_debug("\t%-20s: %s\n", udev_list_entry_get_name(list),
+				udev_list_entry_get_value(list));
 
-	if (udev->socket >= 0)
-		close(udev->socket);
+	if (!strcmp(action, "add"))
+		return udev_handle_dev_add(udev, dev);
+
+	else if (!strcmp(action, "remove"))
+		return udev_handle_dev_remove(udev, dev);
+
+	else if (!strcmp(action, "change"))
+		return udev_handle_dev_change(udev, dev);
 
 	return 0;
 }
 
-struct udev *udev_init(struct device_handler *handler)
+static int udev_enumerate(struct udev *udev)
 {
-	struct sockaddr_un addr;
-	struct udev *udev;
+	int result;
+	struct udev_list_entry *list, *entry;
+	struct udev_enumerate *enumerate;
 
-	unlink(PBOOT_DEVICE_SOCKET);
+	enumerate = udev_enumerate_new(udev);
 
-	udev = talloc(NULL, struct udev);
+	if (!enumerate) {
+		pb_log("udev_enumerate_new failed\n");
+		return -1;
+	}
 
-	udev->handler = handler;
+	result = udev_enumerate_add_match_subsystem(enumerate, "block");
+	if (result) {
+		pb_log("udev_enumerate_add_match_subsystem failed\n");
+		goto fail;
+	}
+
+	result = udev_enumerate_add_match_is_initialized(enumerate);
+	if (result) {
+		pb_log("udev_enumerate_add_match_is_initialised failed\n");
+		goto fail;
+	}
 
-	udev->socket = socket(PF_UNIX, SOCK_DGRAM, 0);
-	if (udev->socket < 0) {
-		pb_log("Error creating udev socket: %s\n", strerror(errno));
+	udev_enumerate_scan_devices(enumerate);
+
+	list = udev_enumerate_get_list_entry(enumerate);
+
+	udev_list_entry_foreach(entry, list) {
+		const char *syspath;
+		struct udev_device *dev;
+
+		syspath = udev_list_entry_get_name(entry);
+		dev = udev_device_new_from_syspath(udev, syspath);
+
+		udev_handle_dev_action(dev, "add");
+
+		udev_device_unref(dev);
+	}
+
+	udev_enumerate_unref(enumerate);
+	return 0;
+
+fail:
+	udev_enumerate_unref(enumerate);
+	return -1;
+}
+
+static int udev_setup_monitor(struct udev *udev, struct udev_monitor **monitor)
+{
+	int result;
+	struct udev_monitor *m;
+
+	*monitor = NULL;
+	m = udev_monitor_new_from_netlink(udev, "udev");
+
+	if (!m) {
+		pb_log("udev_monitor_new_from_netlink failed\n");
 		goto out_err;
 	}
 
-	talloc_set_destructor(udev, udev_destructor);
+	result = udev_monitor_set_receive_buffer_size(m, monitor_bufsize);
+	if (result) {
+		pb_log("udev_monitor_set_rx_bufsize(%d) failed\n",
+			monitor_bufsize);
+	}
 
-	addr.sun_family = AF_UNIX;
-	strcpy(addr.sun_path, PBOOT_DEVICE_SOCKET);
+	result = udev_monitor_filter_add_match_subsystem_devtype(m, "block",
+		NULL);
 
-	if (bind(udev->socket, (struct sockaddr *)&addr, sizeof(addr))) {
-		pb_log("Error binding udev socket: %s\n", strerror(errno));
+	if (result) {
+		pb_log("udev_monitor_filter_add_match_subsystem_devtype failed\n");
 		goto out_err;
 	}
 
-	waiter_register(udev->socket, WAIT_IN, udev_process, udev);
+	result = udev_monitor_enable_receiving(m);
 
-	return udev;
+	if (result) {
+		pb_log("udev_monitor_enable_receiving failed\n");
+		goto out_err;
+	}
+
+	*monitor = m;
+	return 0;
 
 out_err:
+	udev_monitor_unref(m);
+	return -1;
+}
+
+/*
+ * udev_process - waiter callback for monitor netlink.
+ */
+
+static int udev_process(void *arg)
+{
+	struct udev_monitor *monitor = arg;
+	struct udev_device *dev;
+	const char *action;
+
+	dev = udev_monitor_receive_device(monitor);
+	if (!dev) {
+		pb_log("udev_monitor_receive_device failed\n");
+		return -1;
+	}
+
+	action = udev_device_get_action(dev);
+
+	if (!action) {
+		pb_log("udev_device_get_action failed\n");
+	} else {
+		udev_handle_dev_action(dev, action);
+	}
+
+	udev_device_unref(dev);
+	return 0;
+}
+
+static void udev_log_fn(struct udev __attribute__((unused)) *udev,
+	int __attribute__((unused)) priority, const char *file, int line,
+	const char *fn, const char *format, va_list args)
+{
+      pb_log("libudev: %s %s:%d: ", fn, file, line);
+      vfprintf(pb_log_get_stream(), format, args);
+}
+
+struct pb_udev *udev_init(struct device_handler *handler,
+		struct waitset *waitset)
+{
+	struct pb_udev *udev;
+	int result;
+
+	udev = talloc_zero(handler, struct pb_udev);
+	talloc_set_destructor(udev, udev_destructor);
+	udev->handler = handler;
+
+	udev->udev = udev_new();
+
+	if (!udev->udev) {
+		pb_log("udev_new failed\n");
+		goto fail;
+	}
+
+	udev_set_userdata(udev->udev, udev);
+
+	udev_set_log_fn(udev->udev, udev_log_fn);
+
+	result = udev_setup_monitor(udev->udev, &udev->monitor);
+	if (result)
+		goto fail;
+
+	result = udev_enumerate(udev->udev);
+	if (result)
+		goto fail;
+
+	waiter_register_io(waitset, udev_monitor_get_fd(udev->monitor), WAIT_IN,
+		udev_process, udev->monitor);
+
+	pb_debug("%s: waiting on udev\n", __func__);
+
+	return udev;
+
+fail:
 	talloc_free(udev);
 	return NULL;
 }
 
-void udev_destroy(struct udev *udev)
+void udev_reinit(struct pb_udev *udev)
 {
-	talloc_free(udev);
+	pb_log("udev: reinit requested, starting enumeration\n");
+	udev_enumerate(udev->udev);
 }