--- /dev/null
+/*
+ * Device Mapper Uevent Support (dm-uevent)
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2007
+ * Author: Mike Anderson <andmike@linux.vnet.ibm.com>
+ */
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/kobject.h>
+#include <linux/dm-ioctl.h>
+#include <linux/export.h>
+
+#include "dm.h"
+#include "dm-uevent.h"
+
+#define DM_MSG_PREFIX "uevent"
+
+static const struct {
+ enum dm_uevent_type type;
+ enum kobject_action action;
+ char *name;
+} _dm_uevent_type_names[] = {
+ {DM_UEVENT_PATH_FAILED, KOBJ_CHANGE, "PATH_FAILED"},
+ {DM_UEVENT_PATH_REINSTATED, KOBJ_CHANGE, "PATH_REINSTATED"},
+};
+
+static struct kmem_cache *_dm_event_cache;
+
+struct dm_uevent {
+ struct mapped_device *md;
+ enum kobject_action action;
+ struct kobj_uevent_env ku_env;
+ struct list_head elist;
+ char name[DM_NAME_LEN];
+ char uuid[DM_UUID_LEN];
+};
+
+static void dm_uevent_free(struct dm_uevent *event)
+{
+ kmem_cache_free(_dm_event_cache, event);
+}
+
+static struct dm_uevent *dm_uevent_alloc(struct mapped_device *md)
+{
+ struct dm_uevent *event;
+
+ event = kmem_cache_zalloc(_dm_event_cache, GFP_ATOMIC);
+ if (!event)
+ return NULL;
+
+ INIT_LIST_HEAD(&event->elist);
+ event->md = md;
+
+ return event;
+}
+
+static struct dm_uevent *dm_build_path_uevent(struct mapped_device *md,
+ struct dm_target *ti,
+ enum kobject_action action,
+ const char *dm_action,
+ const char *path,
+ unsigned nr_valid_paths)
+{
+ struct dm_uevent *event;
+
+ event = dm_uevent_alloc(md);
+ if (!event) {
+ DMERR("%s: dm_uevent_alloc() failed", __func__);
+ goto err_nomem;
+ }
+
+ event->action = action;
+
+ if (add_uevent_var(&event->ku_env, "DM_TARGET=%s", ti->type->name)) {
+ DMERR("%s: add_uevent_var() for DM_TARGET failed",
+ __func__);
+ goto err_add;
+ }
+
+ if (add_uevent_var(&event->ku_env, "DM_ACTION=%s", dm_action)) {
+ DMERR("%s: add_uevent_var() for DM_ACTION failed",
+ __func__);
+ goto err_add;
+ }
+
+ if (add_uevent_var(&event->ku_env, "DM_SEQNUM=%u",
+ dm_next_uevent_seq(md))) {
+ DMERR("%s: add_uevent_var() for DM_SEQNUM failed",
+ __func__);
+ goto err_add;
+ }
+
+ if (add_uevent_var(&event->ku_env, "DM_PATH=%s", path)) {
+ DMERR("%s: add_uevent_var() for DM_PATH failed", __func__);
+ goto err_add;
+ }
+
+ if (add_uevent_var(&event->ku_env, "DM_NR_VALID_PATHS=%d",
+ nr_valid_paths)) {
+ DMERR("%s: add_uevent_var() for DM_NR_VALID_PATHS failed",
+ __func__);
+ goto err_add;
+ }
+
+ return event;
+
+err_add:
+ dm_uevent_free(event);
+err_nomem:
+ return ERR_PTR(-ENOMEM);
+}
+
+/**
+ * dm_send_uevents - send uevents for given list
+ *
+ * @events: list of events to send
+ * @kobj: kobject generating event
+ *
+ */
+void dm_send_uevents(struct list_head *events, struct kobject *kobj)
+{
+ int r;
+ struct dm_uevent *event, *next;
+
+ list_for_each_entry_safe(event, next, events, elist) {
+ list_del_init(&event->elist);
+
+ /*
+ * When a device is being removed this copy fails and we
+ * discard these unsent events.
+ */
+ if (dm_copy_name_and_uuid(event->md, event->name,
+ event->uuid)) {
+ DMINFO("%s: skipping sending uevent for lost device",
+ __func__);
+ goto uevent_free;
+ }
+
+ if (add_uevent_var(&event->ku_env, "DM_NAME=%s", event->name)) {
+ DMERR("%s: add_uevent_var() for DM_NAME failed",
+ __func__);
+ goto uevent_free;
+ }
+
+ if (add_uevent_var(&event->ku_env, "DM_UUID=%s", event->uuid)) {
+ DMERR("%s: add_uevent_var() for DM_UUID failed",
+ __func__);
+ goto uevent_free;
+ }
+
+ r = kobject_uevent_env(kobj, event->action, event->ku_env.envp);
+ if (r)
+ DMERR("%s: kobject_uevent_env failed", __func__);
+uevent_free:
+ dm_uevent_free(event);
+ }
+}
+EXPORT_SYMBOL_GPL(dm_send_uevents);
+
+/**
+ * dm_path_uevent - called to create a new path event and queue it
+ *
+ * @event_type: path event type enum
+ * @ti: pointer to a dm_target
+ * @path: string containing pathname
+ * @nr_valid_paths: number of valid paths remaining
+ *
+ */
+void dm_path_uevent(enum dm_uevent_type event_type, struct dm_target *ti,
+ const char *path, unsigned nr_valid_paths)
+{
+ struct mapped_device *md = dm_table_get_md(ti->table);
+ struct dm_uevent *event;
+
+ if (event_type >= ARRAY_SIZE(_dm_uevent_type_names)) {
+ DMERR("%s: Invalid event_type %d", __func__, event_type);
+ return;
+ }
+
+ event = dm_build_path_uevent(md, ti,
+ _dm_uevent_type_names[event_type].action,
+ _dm_uevent_type_names[event_type].name,
+ path, nr_valid_paths);
+ if (IS_ERR(event))
+ return;
+
+ dm_uevent_add(md, &event->elist);
+}
+EXPORT_SYMBOL_GPL(dm_path_uevent);
+
+int dm_uevent_init(void)
+{
+ _dm_event_cache = KMEM_CACHE(dm_uevent, 0);
+ if (!_dm_event_cache)
+ return -ENOMEM;
+
+ DMINFO("version 1.0.3");
+
+ return 0;
+}
+
+void dm_uevent_exit(void)
+{
+ kmem_cache_destroy(_dm_event_cache);
+}
Code Review / kvmfornfv.git / blobdiff