/* * 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 "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); }