Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Device Mapper Uevent Support (dm-uevent) |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License as published by the |
| 6 | * Free Software Foundation; either version 2 of the License, or (at your |
| 7 | * option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but |
| 10 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License along |
| 15 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 16 | * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | * |
| 18 | * Copyright IBM Corporation, 2007 |
| 19 | * Author: Mike Anderson <andmike@linux.vnet.ibm.com> |
| 20 | */ |
| 21 | #include <linux/list.h> |
| 22 | #include <linux/slab.h> |
| 23 | #include <linux/kobject.h> |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 24 | #include <linux/dm-ioctl.h> |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 25 | |
| 26 | #include "dm.h" |
| 27 | #include "dm-uevent.h" |
| 28 | |
| 29 | #define DM_MSG_PREFIX "uevent" |
| 30 | |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 31 | static const struct { |
| 32 | enum dm_uevent_type type; |
| 33 | enum kobject_action action; |
| 34 | char *name; |
| 35 | } _dm_uevent_type_names[] = { |
| 36 | {DM_UEVENT_PATH_FAILED, KOBJ_CHANGE, "PATH_FAILED"}, |
| 37 | {DM_UEVENT_PATH_REINSTATED, KOBJ_CHANGE, "PATH_REINSTATED"}, |
| 38 | }; |
| 39 | |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 40 | static struct kmem_cache *_dm_event_cache; |
| 41 | |
| 42 | struct dm_uevent { |
| 43 | struct mapped_device *md; |
| 44 | enum kobject_action action; |
| 45 | struct kobj_uevent_env ku_env; |
| 46 | struct list_head elist; |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 47 | char name[DM_NAME_LEN]; |
| 48 | char uuid[DM_UUID_LEN]; |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 49 | }; |
| 50 | |
| 51 | static void dm_uevent_free(struct dm_uevent *event) |
| 52 | { |
| 53 | kmem_cache_free(_dm_event_cache, event); |
| 54 | } |
| 55 | |
| 56 | static struct dm_uevent *dm_uevent_alloc(struct mapped_device *md) |
| 57 | { |
| 58 | struct dm_uevent *event; |
| 59 | |
| 60 | event = kmem_cache_zalloc(_dm_event_cache, GFP_ATOMIC); |
| 61 | if (!event) |
| 62 | return NULL; |
| 63 | |
| 64 | INIT_LIST_HEAD(&event->elist); |
| 65 | event->md = md; |
| 66 | |
| 67 | return event; |
| 68 | } |
| 69 | |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 70 | static struct dm_uevent *dm_build_path_uevent(struct mapped_device *md, |
| 71 | struct dm_target *ti, |
| 72 | enum kobject_action action, |
| 73 | const char *dm_action, |
| 74 | const char *path, |
| 75 | unsigned nr_valid_paths) |
| 76 | { |
| 77 | struct dm_uevent *event; |
| 78 | |
| 79 | event = dm_uevent_alloc(md); |
| 80 | if (!event) { |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 81 | DMERR("%s: dm_uevent_alloc() failed", __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 82 | goto err_nomem; |
| 83 | } |
| 84 | |
| 85 | event->action = action; |
| 86 | |
| 87 | if (add_uevent_var(&event->ku_env, "DM_TARGET=%s", ti->type->name)) { |
| 88 | DMERR("%s: add_uevent_var() for DM_TARGET failed", |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 89 | __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 90 | goto err_add; |
| 91 | } |
| 92 | |
| 93 | if (add_uevent_var(&event->ku_env, "DM_ACTION=%s", dm_action)) { |
| 94 | DMERR("%s: add_uevent_var() for DM_ACTION failed", |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 95 | __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 96 | goto err_add; |
| 97 | } |
| 98 | |
| 99 | if (add_uevent_var(&event->ku_env, "DM_SEQNUM=%u", |
| 100 | dm_next_uevent_seq(md))) { |
| 101 | DMERR("%s: add_uevent_var() for DM_SEQNUM failed", |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 102 | __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 103 | goto err_add; |
| 104 | } |
| 105 | |
| 106 | if (add_uevent_var(&event->ku_env, "DM_PATH=%s", path)) { |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 107 | DMERR("%s: add_uevent_var() for DM_PATH failed", __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 108 | goto err_add; |
| 109 | } |
| 110 | |
| 111 | if (add_uevent_var(&event->ku_env, "DM_NR_VALID_PATHS=%d", |
| 112 | nr_valid_paths)) { |
| 113 | DMERR("%s: add_uevent_var() for DM_NR_VALID_PATHS failed", |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 114 | __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 115 | goto err_add; |
| 116 | } |
| 117 | |
| 118 | return event; |
| 119 | |
| 120 | err_add: |
| 121 | dm_uevent_free(event); |
| 122 | err_nomem: |
| 123 | return ERR_PTR(-ENOMEM); |
| 124 | } |
| 125 | |
| 126 | /** |
| 127 | * dm_send_uevents - send uevents for given list |
| 128 | * |
| 129 | * @events: list of events to send |
| 130 | * @kobj: kobject generating event |
| 131 | * |
| 132 | */ |
| 133 | void dm_send_uevents(struct list_head *events, struct kobject *kobj) |
| 134 | { |
| 135 | int r; |
| 136 | struct dm_uevent *event, *next; |
| 137 | |
| 138 | list_for_each_entry_safe(event, next, events, elist) { |
| 139 | list_del_init(&event->elist); |
| 140 | |
| 141 | /* |
Mikulas Patocka | 6076905 | 2009-12-10 23:51:52 +0000 | [diff] [blame^] | 142 | * When a device is being removed this copy fails and we |
| 143 | * discard these unsent events. |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 144 | */ |
| 145 | if (dm_copy_name_and_uuid(event->md, event->name, |
| 146 | event->uuid)) { |
Mikulas Patocka | 6076905 | 2009-12-10 23:51:52 +0000 | [diff] [blame^] | 147 | DMINFO("%s: skipping sending uevent for lost device", |
| 148 | __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 149 | goto uevent_free; |
| 150 | } |
| 151 | |
| 152 | if (add_uevent_var(&event->ku_env, "DM_NAME=%s", event->name)) { |
| 153 | DMERR("%s: add_uevent_var() for DM_NAME failed", |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 154 | __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 155 | goto uevent_free; |
| 156 | } |
| 157 | |
| 158 | if (add_uevent_var(&event->ku_env, "DM_UUID=%s", event->uuid)) { |
| 159 | DMERR("%s: add_uevent_var() for DM_UUID failed", |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 160 | __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 161 | goto uevent_free; |
| 162 | } |
| 163 | |
| 164 | r = kobject_uevent_env(kobj, event->action, event->ku_env.envp); |
| 165 | if (r) |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 166 | DMERR("%s: kobject_uevent_env failed", __func__); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 167 | uevent_free: |
| 168 | dm_uevent_free(event); |
| 169 | } |
| 170 | } |
| 171 | EXPORT_SYMBOL_GPL(dm_send_uevents); |
| 172 | |
| 173 | /** |
| 174 | * dm_path_uevent - called to create a new path event and queue it |
| 175 | * |
| 176 | * @event_type: path event type enum |
| 177 | * @ti: pointer to a dm_target |
| 178 | * @path: string containing pathname |
| 179 | * @nr_valid_paths: number of valid paths remaining |
| 180 | * |
| 181 | */ |
| 182 | void dm_path_uevent(enum dm_uevent_type event_type, struct dm_target *ti, |
| 183 | const char *path, unsigned nr_valid_paths) |
| 184 | { |
| 185 | struct mapped_device *md = dm_table_get_md(ti->table); |
| 186 | struct dm_uevent *event; |
| 187 | |
| 188 | if (event_type >= ARRAY_SIZE(_dm_uevent_type_names)) { |
Harvey Harrison | e46b272 | 2008-04-28 02:15:50 -0700 | [diff] [blame] | 189 | DMERR("%s: Invalid event_type %d", __func__, event_type); |
Mike Anderson | 7a8c3d3 | 2007-10-19 22:48:01 +0100 | [diff] [blame] | 190 | goto out; |
| 191 | } |
| 192 | |
| 193 | event = dm_build_path_uevent(md, ti, |
| 194 | _dm_uevent_type_names[event_type].action, |
| 195 | _dm_uevent_type_names[event_type].name, |
| 196 | path, nr_valid_paths); |
| 197 | if (IS_ERR(event)) |
| 198 | goto out; |
| 199 | |
| 200 | dm_uevent_add(md, &event->elist); |
| 201 | |
| 202 | out: |
| 203 | dm_put(md); |
| 204 | } |
| 205 | EXPORT_SYMBOL_GPL(dm_path_uevent); |
| 206 | |
Mike Anderson | 51e5b2b | 2007-10-19 22:48:00 +0100 | [diff] [blame] | 207 | int dm_uevent_init(void) |
| 208 | { |
| 209 | _dm_event_cache = KMEM_CACHE(dm_uevent, 0); |
| 210 | if (!_dm_event_cache) |
| 211 | return -ENOMEM; |
| 212 | |
| 213 | DMINFO("version 1.0.3"); |
| 214 | |
| 215 | return 0; |
| 216 | } |
| 217 | |
| 218 | void dm_uevent_exit(void) |
| 219 | { |
| 220 | kmem_cache_destroy(_dm_event_cache); |
| 221 | } |