Commit | Line | Data |
---|---|---|
1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
51e5b2bd MA |
2 | /* |
3 | * Device Mapper Uevent Support (dm-uevent) | |
4 | * | |
51e5b2bd | 5 | * Copyright IBM Corporation, 2007 |
8ca817c4 | 6 | * Author: Mike Anderson <andmike@linux.vnet.ibm.com> |
51e5b2bd MA |
7 | */ |
8 | #include <linux/list.h> | |
9 | #include <linux/slab.h> | |
10 | #include <linux/kobject.h> | |
7a8c3d3b | 11 | #include <linux/dm-ioctl.h> |
daaa5f7c | 12 | #include <linux/export.h> |
51e5b2bd MA |
13 | |
14 | #include "dm.h" | |
15 | #include "dm-uevent.h" | |
16 | ||
17 | #define DM_MSG_PREFIX "uevent" | |
18 | ||
7a8c3d3b MA |
19 | static const struct { |
20 | enum dm_uevent_type type; | |
21 | enum kobject_action action; | |
22 | char *name; | |
23 | } _dm_uevent_type_names[] = { | |
24 | {DM_UEVENT_PATH_FAILED, KOBJ_CHANGE, "PATH_FAILED"}, | |
25 | {DM_UEVENT_PATH_REINSTATED, KOBJ_CHANGE, "PATH_REINSTATED"}, | |
26 | }; | |
27 | ||
51e5b2bd MA |
28 | static struct kmem_cache *_dm_event_cache; |
29 | ||
30 | struct dm_uevent { | |
31 | struct mapped_device *md; | |
32 | enum kobject_action action; | |
33 | struct kobj_uevent_env ku_env; | |
34 | struct list_head elist; | |
7a8c3d3b MA |
35 | char name[DM_NAME_LEN]; |
36 | char uuid[DM_UUID_LEN]; | |
51e5b2bd MA |
37 | }; |
38 | ||
39 | static void dm_uevent_free(struct dm_uevent *event) | |
40 | { | |
41 | kmem_cache_free(_dm_event_cache, event); | |
42 | } | |
43 | ||
44 | static struct dm_uevent *dm_uevent_alloc(struct mapped_device *md) | |
45 | { | |
46 | struct dm_uevent *event; | |
47 | ||
48 | event = kmem_cache_zalloc(_dm_event_cache, GFP_ATOMIC); | |
49 | if (!event) | |
50 | return NULL; | |
51 | ||
52 | INIT_LIST_HEAD(&event->elist); | |
53 | event->md = md; | |
54 | ||
55 | return event; | |
56 | } | |
57 | ||
7a8c3d3b MA |
58 | static struct dm_uevent *dm_build_path_uevent(struct mapped_device *md, |
59 | struct dm_target *ti, | |
60 | enum kobject_action action, | |
61 | const char *dm_action, | |
62 | const char *path, | |
86a3238c | 63 | unsigned int nr_valid_paths) |
7a8c3d3b MA |
64 | { |
65 | struct dm_uevent *event; | |
66 | ||
67 | event = dm_uevent_alloc(md); | |
68 | if (!event) { | |
e46b272b | 69 | DMERR("%s: dm_uevent_alloc() failed", __func__); |
7a8c3d3b MA |
70 | goto err_nomem; |
71 | } | |
72 | ||
73 | event->action = action; | |
74 | ||
75 | if (add_uevent_var(&event->ku_env, "DM_TARGET=%s", ti->type->name)) { | |
76 | DMERR("%s: add_uevent_var() for DM_TARGET failed", | |
e46b272b | 77 | __func__); |
7a8c3d3b MA |
78 | goto err_add; |
79 | } | |
80 | ||
81 | if (add_uevent_var(&event->ku_env, "DM_ACTION=%s", dm_action)) { | |
82 | DMERR("%s: add_uevent_var() for DM_ACTION failed", | |
e46b272b | 83 | __func__); |
7a8c3d3b MA |
84 | goto err_add; |
85 | } | |
86 | ||
87 | if (add_uevent_var(&event->ku_env, "DM_SEQNUM=%u", | |
88 | dm_next_uevent_seq(md))) { | |
89 | DMERR("%s: add_uevent_var() for DM_SEQNUM failed", | |
e46b272b | 90 | __func__); |
7a8c3d3b MA |
91 | goto err_add; |
92 | } | |
93 | ||
94 | if (add_uevent_var(&event->ku_env, "DM_PATH=%s", path)) { | |
e46b272b | 95 | DMERR("%s: add_uevent_var() for DM_PATH failed", __func__); |
7a8c3d3b MA |
96 | goto err_add; |
97 | } | |
98 | ||
99 | if (add_uevent_var(&event->ku_env, "DM_NR_VALID_PATHS=%d", | |
100 | nr_valid_paths)) { | |
101 | DMERR("%s: add_uevent_var() for DM_NR_VALID_PATHS failed", | |
e46b272b | 102 | __func__); |
7a8c3d3b MA |
103 | goto err_add; |
104 | } | |
105 | ||
106 | return event; | |
107 | ||
108 | err_add: | |
109 | dm_uevent_free(event); | |
110 | err_nomem: | |
111 | return ERR_PTR(-ENOMEM); | |
112 | } | |
113 | ||
114 | /** | |
115 | * dm_send_uevents - send uevents for given list | |
116 | * | |
117 | * @events: list of events to send | |
118 | * @kobj: kobject generating event | |
119 | * | |
120 | */ | |
121 | void dm_send_uevents(struct list_head *events, struct kobject *kobj) | |
122 | { | |
123 | int r; | |
124 | struct dm_uevent *event, *next; | |
125 | ||
126 | list_for_each_entry_safe(event, next, events, elist) { | |
127 | list_del_init(&event->elist); | |
128 | ||
129 | /* | |
6076905b MP |
130 | * When a device is being removed this copy fails and we |
131 | * discard these unsent events. | |
7a8c3d3b MA |
132 | */ |
133 | if (dm_copy_name_and_uuid(event->md, event->name, | |
134 | event->uuid)) { | |
6076905b MP |
135 | DMINFO("%s: skipping sending uevent for lost device", |
136 | __func__); | |
7a8c3d3b MA |
137 | goto uevent_free; |
138 | } | |
139 | ||
140 | if (add_uevent_var(&event->ku_env, "DM_NAME=%s", event->name)) { | |
141 | DMERR("%s: add_uevent_var() for DM_NAME failed", | |
e46b272b | 142 | __func__); |
7a8c3d3b MA |
143 | goto uevent_free; |
144 | } | |
145 | ||
146 | if (add_uevent_var(&event->ku_env, "DM_UUID=%s", event->uuid)) { | |
147 | DMERR("%s: add_uevent_var() for DM_UUID failed", | |
e46b272b | 148 | __func__); |
7a8c3d3b MA |
149 | goto uevent_free; |
150 | } | |
151 | ||
152 | r = kobject_uevent_env(kobj, event->action, event->ku_env.envp); | |
153 | if (r) | |
e46b272b | 154 | DMERR("%s: kobject_uevent_env failed", __func__); |
7a8c3d3b MA |
155 | uevent_free: |
156 | dm_uevent_free(event); | |
157 | } | |
158 | } | |
159 | EXPORT_SYMBOL_GPL(dm_send_uevents); | |
160 | ||
161 | /** | |
162 | * dm_path_uevent - called to create a new path event and queue it | |
163 | * | |
164 | * @event_type: path event type enum | |
165 | * @ti: pointer to a dm_target | |
166 | * @path: string containing pathname | |
167 | * @nr_valid_paths: number of valid paths remaining | |
168 | * | |
169 | */ | |
170 | void dm_path_uevent(enum dm_uevent_type event_type, struct dm_target *ti, | |
86a3238c | 171 | const char *path, unsigned int nr_valid_paths) |
7a8c3d3b MA |
172 | { |
173 | struct mapped_device *md = dm_table_get_md(ti->table); | |
174 | struct dm_uevent *event; | |
175 | ||
176 | if (event_type >= ARRAY_SIZE(_dm_uevent_type_names)) { | |
e46b272b | 177 | DMERR("%s: Invalid event_type %d", __func__, event_type); |
ecdb2e25 | 178 | return; |
7a8c3d3b MA |
179 | } |
180 | ||
181 | event = dm_build_path_uevent(md, ti, | |
182 | _dm_uevent_type_names[event_type].action, | |
183 | _dm_uevent_type_names[event_type].name, | |
184 | path, nr_valid_paths); | |
185 | if (IS_ERR(event)) | |
ecdb2e25 | 186 | return; |
7a8c3d3b MA |
187 | |
188 | dm_uevent_add(md, &event->elist); | |
7a8c3d3b MA |
189 | } |
190 | EXPORT_SYMBOL_GPL(dm_path_uevent); | |
191 | ||
51e5b2bd MA |
192 | int dm_uevent_init(void) |
193 | { | |
194 | _dm_event_cache = KMEM_CACHE(dm_uevent, 0); | |
195 | if (!_dm_event_cache) | |
196 | return -ENOMEM; | |
197 | ||
198 | DMINFO("version 1.0.3"); | |
199 | ||
200 | return 0; | |
201 | } | |
202 | ||
203 | void dm_uevent_exit(void) | |
204 | { | |
205 | kmem_cache_destroy(_dm_event_cache); | |
206 | } |