discover: Change parsers to explicitly request configuration files
[petitboot] / discover / udev.c
index fb64221dad1d90036db782a3a1762f441e27e45c..48ab745b4f371ac410048dc3ab7b93f9dc3ff4fb 100644 (file)
@@ -1,7 +1,9 @@
 
 #define _GNU_SOURCE
 
+#include <assert.h>
 #include <errno.h>
+#include <libudev.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -11,6 +13,7 @@
 #include <sys/un.h>
 
 #include <log/log.h>
+#include <types/types.h>
 #include <talloc/talloc.h>
 #include <waiter/waiter.h>
 #include <system/system.h>
 #include "pb-discover.h"
 #include "device-handler.h"
 
-#define PBOOT_DEVICE_SOCKET "/tmp/petitboot.udev"
-
-#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 udev_print_event(struct event *event)
+static int udev_destructor(void *p)
 {
-       const char *action, *params[] = {
-               "DEVNAME",
-               "DEVPATH",
-               "ID_TYPE",
-               "ID_BUS",
-               "ID_FS_UUID",
-               "ID_FS_LABEL",
-               NULL,
-       };
-       int i;
-
-       action = event->action == EVENT_ACTION_ADD ? "add" : "remove";
-
-       pb_log("udev %s event:\n", action);
-       pb_log("\tdevice: %s\n", event->device);
-
-       for (i = 0; params[i]; i++)
-               pb_log("\t%-12s => %s\n",
-                               params[i], event_get_param(event, params[i]));
-}
+       struct pb_udev *udev = p;
 
-static void udev_handle_message(struct udev *udev, char *buf, int len)
-{
-       int result;
-       struct event *event;
-       const char *devpath;
+       udev_monitor_unref(udev->monitor);
+       udev->monitor = NULL;
 
-       event = talloc(udev, struct event);
-       event->type = EVENT_TYPE_UDEV;
+       udev_unref(udev->udev);
+       udev->udev = NULL;
 
-       pb_log("%s\n", buf);
+       return 0;
+}
 
-       result = event_parse_ad_message(event, buf, len);
+static void udev_setup_device_params(struct udev_device *udev,
+               struct discover_device *dev)
+{
+       struct udev_list_entry *list, *entry;
 
-       if (result)
+       list = udev_device_get_properties_list_entry(udev);
+       if (!list)
                return;
 
-       udev_print_event(event);
+       udev_list_entry_foreach(entry, list)
+               discover_device_set_param(dev,
+                               udev_list_entry_get_name(entry),
+                               udev_list_entry_get_value(entry));
+}
 
-       /* Ignore ram, loop, and devices with no DEVNAME. */
+static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev)
+{
+       struct discover_device *ddev;
+       const char *typestr;
+       const char *serial;
+       const char *path;
+       const char *name;
+       const char *prop;
+
+       name = udev_device_get_sysname(dev);
+       if (!name) {
+               pb_debug("udev_device_get_sysname failed\n");
+               return -1;
+       }
 
-       devpath = event_get_param(event, "DEVPATH");
+       typestr = udev_device_get_devtype(dev);
+       if (!typestr) {
+               pb_debug("udev_device_get_devtype failed\n");
+               return -1;
+       }
 
-       if (event_get_param(event, "DEVNAME")
-               && !strstr(devpath, "virtual/block/loop")
-               && !strstr(devpath, "virtual/block/ram")) {
-               device_handler_event(udev->handler, event);
+       if (!(!strcmp(typestr, "disk") || !strcmp(typestr, "partition"))) {
+               pb_debug("SKIP %s: invalid type %s\n", name, typestr);
+               return 0;
+       }
+
+       path = udev_device_get_devpath(dev);
+       if (path && (strstr(path, "virtual/block/loop")
+                       || strstr(path, "virtual/block/ram"))) {
+               pb_debug("SKIP: %s: ignored (path=%s)\n", name, path);
+               return 0;
        }
 
-       talloc_free(event);
+       /* We have enough info to create the device and start discovery */
+       ddev = device_lookup_by_id(udev->handler, name);
+       if (ddev) {
+               pb_debug("device %s is already present?\n", name);
+               return -1;
+       }
+
+       /* we may also see multipath devices; same dev nodes (hence id), but
+        * different serial numbers */
+       serial = udev_device_get_property_value(dev, "ID_SERIAL");
+       if (serial && device_lookup_by_serial(udev->handler, serial))
+               return -1;
+
+       ddev = discover_device_create(udev->handler, name);
+
+       ddev->device_path = udev_device_get_devnode(dev);
+       prop = udev_device_get_property_value(dev, "ID_FS_UUID");
+       if (prop)
+               ddev->uuid = talloc_strdup(ddev, prop);
+       prop = udev_device_get_property_value(dev, "ID_FS_LABEL");
+       if (prop)
+               ddev->label = talloc_strdup(ddev, prop);
+       ddev->device->type = DEVICE_TYPE_DISK;
 
-       return;
+       udev_setup_device_params(dev, ddev);
+
+       device_handler_discover(udev->handler, ddev);
+
+       return 0;
 }
 
-static int udev_process(void *arg)
+static int udev_handle_dev_remove(struct pb_udev *udev, struct udev_device *dev)
 {
-       struct udev *udev = arg;
-       char buf[4096];
-       int len;
+       struct discover_device *ddev;
+       const char *name;
 
-       len = recvfrom(udev->socket, buf, sizeof(buf), 0, NULL, NULL);
-
-       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;
 
-       udev_handle_message(udev, buf, len);
+       device_handler_remove(udev->handler, ddev);
 
        return 0;
 }
-
-static int udev_destructor(void *p)
+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));
 
-       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);
 
        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");
 
-       udev->socket = socket(PF_UNIX, SOCK_DGRAM, 0);
-       if (udev->socket < 0) {
-               pb_log("Error creating udev socket: %s\n", strerror(errno));
-               goto out_err;
+       if (result) {
+               pb_log("udev_enumerate_add_match_subsystem failed\n");
+               goto fail;
        }
 
-       talloc_set_destructor(udev, udev_destructor);
+       udev_enumerate_scan_devices(enumerate);
+
+       list = udev_enumerate_get_list_entry(enumerate);
+
+       if (!list) {
+               pb_log("udev_enumerate_get_list_entry failed\n");
+               goto fail;
+       }
+
+       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);
 
-       memset(&addr, 0, sizeof addr);
-       addr.sun_family = AF_UNIX;
-       strcpy(addr.sun_path, PBOOT_DEVICE_SOCKET);
+               udev_handle_dev_action(dev, "add");
+
+               udev_device_unref(dev);
+       }
+
+       udev_enumerate_unref(enumerate);
+       return 0;
+
+fail:
+       udev_enumerate_unref(enumerate);
+       return -1;
+}
 
-       if (bind(udev->socket, (struct sockaddr *)&addr, sizeof(addr))) {
-               pb_log("Error binding udev socket: %s\n", strerror(errno));
+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;
        }
 
-       waiter_register(udev->socket, WAIT_IN, udev_process, udev);
+       result = udev_monitor_filter_add_match_subsystem_devtype(m, "block",
+               NULL);
 
-       pb_log("%s: waiting on %s\n", __func__, PBOOT_DEVICE_SOCKET);
+       if (result) {
+               pb_log("udev_monitor_filter_add_match_subsystem_devtype failed\n");
+               goto out_err;
+       }
 
-       return udev;
+       result = udev_monitor_enable_receiving(m);
+
+       if (result) {
+               pb_log("udev_monitor_enable_receiving failed\n");
+               goto out_err;
+       }
+
+       *monitor = m;
+       return 0;
 
 out_err:
-       talloc_free(udev);
-       return NULL;
+       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;
+       int result;
+
+       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");
+               goto fail;
+       }
+
+       result = udev_handle_dev_action(dev, action);
+
+       udev_device_unref(dev);
+       return result;
+
+fail:
+       udev_device_unref(dev);
+       return -1;
+}
+
+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);
 }
 
-int udev_trigger(struct udev __attribute__((unused)) *udev)
+struct pb_udev *udev_init(struct waitset *waitset,
+       struct device_handler *handler)
 {
-       const char *cmd[] = {
-               "/sbin/udevadm,
-               "trigger",
-               "--subsystem-match=block",
-               "--action=add",
-               NULL,
-       };
-       int rc;
+       int result;
+       struct pb_udev *udev = talloc(NULL, 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_new;
+       }
+
+       udev_set_userdata(udev->udev, udev);
 
-       rc = pb_run_cmd(cmd, 1, 0);
+       udev_set_log_fn(udev->udev, udev_log_fn);
 
-       if (rc)
-               pb_log("udev trigger failed: %d (%d)\n", rc, WEXITSTATUS(rc));
+       result = udev_enumerate(udev->udev);
+
+       if (result)
+               goto fail_enumerate;
+
+       result = udev_setup_monitor(udev->udev, &udev->monitor);
+
+       if (result)
+               goto fail_monitor;
 
-       return WEXITSTATUS(rc);
+       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_monitor:
+fail_enumerate:
+       udev_unref(udev->udev);
+fail_new:
+       talloc_free(udev);
+       return NULL;
 }
 
-void udev_destroy(struct udev *udev)
+void udev_destroy(struct pb_udev *udev)
 {
        talloc_free(udev);
 }