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-rw-r--r--lib/kobject_uevent.c349
1 files changed, 120 insertions, 229 deletions
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index 3ab375411e38..f56e27ae9d52 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -19,14 +19,16 @@
19#include <linux/skbuff.h> 19#include <linux/skbuff.h>
20#include <linux/netlink.h> 20#include <linux/netlink.h>
21#include <linux/string.h> 21#include <linux/string.h>
22#include <linux/kobject_uevent.h>
23#include <linux/kobject.h> 22#include <linux/kobject.h>
24#include <net/sock.h> 23#include <net/sock.h>
25 24
26#define BUFFER_SIZE 1024 /* buffer for the hotplug env */ 25#define BUFFER_SIZE 1024 /* buffer for the variables */
27#define NUM_ENVP 32 /* number of env pointers */ 26#define NUM_ENVP 32 /* number of env pointers */
28 27
29#if defined(CONFIG_KOBJECT_UEVENT) || defined(CONFIG_HOTPLUG) 28#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
29static DEFINE_SPINLOCK(sequence_lock);
30static struct sock *uevent_sock;
31
30static char *action_to_string(enum kobject_action action) 32static char *action_to_string(enum kobject_action action)
31{ 33{
32 switch (action) { 34 switch (action) {
@@ -36,10 +38,6 @@ static char *action_to_string(enum kobject_action action)
36 return "remove"; 38 return "remove";
37 case KOBJ_CHANGE: 39 case KOBJ_CHANGE:
38 return "change"; 40 return "change";
39 case KOBJ_MOUNT:
40 return "mount";
41 case KOBJ_UMOUNT:
42 return "umount";
43 case KOBJ_OFFLINE: 41 case KOBJ_OFFLINE:
44 return "offline"; 42 return "offline";
45 case KOBJ_ONLINE: 43 case KOBJ_ONLINE:
@@ -48,306 +46,183 @@ static char *action_to_string(enum kobject_action action)
48 return NULL; 46 return NULL;
49 } 47 }
50} 48}
51#endif
52
53#ifdef CONFIG_KOBJECT_UEVENT
54static struct sock *uevent_sock;
55 49
56/** 50/**
57 * send_uevent - notify userspace by sending event through netlink socket 51 * kobject_uevent - notify userspace by ending an uevent
58 * 52 *
59 * @signal: signal name 53 * @action: action that is happening (usually KOBJ_ADD and KOBJ_REMOVE)
60 * @obj: object path (kobject)
61 * @envp: possible hotplug environment to pass with the message
62 * @gfp_mask:
63 */
64static int send_uevent(const char *signal, const char *obj,
65 char **envp, gfp_t gfp_mask)
66{
67 struct sk_buff *skb;
68 char *pos;
69 int len;
70
71 if (!uevent_sock)
72 return -EIO;
73
74 len = strlen(signal) + 1;
75 len += strlen(obj) + 1;
76
77 /* allocate buffer with the maximum possible message size */
78 skb = alloc_skb(len + BUFFER_SIZE, gfp_mask);
79 if (!skb)
80 return -ENOMEM;
81
82 pos = skb_put(skb, len);
83 sprintf(pos, "%s@%s", signal, obj);
84
85 /* copy the environment key by key to our continuous buffer */
86 if (envp) {
87 int i;
88
89 for (i = 2; envp[i]; i++) {
90 len = strlen(envp[i]) + 1;
91 pos = skb_put(skb, len);
92 strcpy(pos, envp[i]);
93 }
94 }
95
96 NETLINK_CB(skb).dst_group = 1;
97 return netlink_broadcast(uevent_sock, skb, 0, 1, gfp_mask);
98}
99
100static int do_kobject_uevent(struct kobject *kobj, enum kobject_action action,
101 struct attribute *attr, gfp_t gfp_mask)
102{
103 char *path;
104 char *attrpath;
105 char *signal;
106 int len;
107 int rc = -ENOMEM;
108
109 path = kobject_get_path(kobj, gfp_mask);
110 if (!path)
111 return -ENOMEM;
112
113 signal = action_to_string(action);
114 if (!signal)
115 return -EINVAL;
116
117 if (attr) {
118 len = strlen(path);
119 len += strlen(attr->name) + 2;
120 attrpath = kmalloc(len, gfp_mask);
121 if (!attrpath)
122 goto exit;
123 sprintf(attrpath, "%s/%s", path, attr->name);
124 rc = send_uevent(signal, attrpath, NULL, gfp_mask);
125 kfree(attrpath);
126 } else
127 rc = send_uevent(signal, path, NULL, gfp_mask);
128
129exit:
130 kfree(path);
131 return rc;
132}
133
134/**
135 * kobject_uevent - notify userspace by sending event through netlink socket
136 *
137 * @signal: signal name
138 * @kobj: struct kobject that the event is happening to
139 * @attr: optional struct attribute the event belongs to
140 */
141int kobject_uevent(struct kobject *kobj, enum kobject_action action,
142 struct attribute *attr)
143{
144 return do_kobject_uevent(kobj, action, attr, GFP_KERNEL);
145}
146EXPORT_SYMBOL_GPL(kobject_uevent);
147
148int kobject_uevent_atomic(struct kobject *kobj, enum kobject_action action,
149 struct attribute *attr)
150{
151 return do_kobject_uevent(kobj, action, attr, GFP_ATOMIC);
152}
153EXPORT_SYMBOL_GPL(kobject_uevent_atomic);
154
155static int __init kobject_uevent_init(void)
156{
157 uevent_sock = netlink_kernel_create(NETLINK_KOBJECT_UEVENT, 1, NULL,
158 THIS_MODULE);
159
160 if (!uevent_sock) {
161 printk(KERN_ERR
162 "kobject_uevent: unable to create netlink socket!\n");
163 return -ENODEV;
164 }
165
166 return 0;
167}
168
169postcore_initcall(kobject_uevent_init);
170
171#else
172static inline int send_uevent(const char *signal, const char *obj,
173 char **envp, int gfp_mask)
174{
175 return 0;
176}
177
178#endif /* CONFIG_KOBJECT_UEVENT */
179
180
181#ifdef CONFIG_HOTPLUG
182char hotplug_path[HOTPLUG_PATH_LEN] = "/sbin/hotplug";
183u64 hotplug_seqnum;
184static DEFINE_SPINLOCK(sequence_lock);
185
186/**
187 * kobject_hotplug - notify userspace by executing /sbin/hotplug
188 *
189 * @action: action that is happening (usually "ADD" or "REMOVE")
190 * @kobj: struct kobject that the action is happening to 54 * @kobj: struct kobject that the action is happening to
191 */ 55 */
192void kobject_hotplug(struct kobject *kobj, enum kobject_action action) 56void kobject_uevent(struct kobject *kobj, enum kobject_action action)
193{ 57{
194 char *argv [3]; 58 char **envp;
195 char **envp = NULL; 59 char *buffer;
196 char *buffer = NULL;
197 char *seq_buff;
198 char *scratch; 60 char *scratch;
61 const char *action_string;
62 const char *devpath = NULL;
63 const char *subsystem;
64 struct kobject *top_kobj;
65 struct kset *kset;
66 struct kset_uevent_ops *uevent_ops;
67 u64 seq;
68 char *seq_buff;
199 int i = 0; 69 int i = 0;
200 int retval; 70 int retval;
201 char *kobj_path = NULL;
202 const char *name = NULL;
203 char *action_string;
204 u64 seq;
205 struct kobject *top_kobj = kobj;
206 struct kset *kset;
207 static struct kset_hotplug_ops null_hotplug_ops;
208 struct kset_hotplug_ops *hotplug_ops = &null_hotplug_ops;
209 71
210 /* If this kobj does not belong to a kset, 72 pr_debug("%s\n", __FUNCTION__);
211 try to find a parent that does. */ 73
74 action_string = action_to_string(action);
75 if (!action_string)
76 return;
77
78 /* search the kset we belong to */
79 top_kobj = kobj;
212 if (!top_kobj->kset && top_kobj->parent) { 80 if (!top_kobj->kset && top_kobj->parent) {
213 do { 81 do {
214 top_kobj = top_kobj->parent; 82 top_kobj = top_kobj->parent;
215 } while (!top_kobj->kset && top_kobj->parent); 83 } while (!top_kobj->kset && top_kobj->parent);
216 } 84 }
217 85 if (!top_kobj->kset)
218 if (top_kobj->kset)
219 kset = top_kobj->kset;
220 else
221 return; 86 return;
222 87
223 if (kset->hotplug_ops) 88 kset = top_kobj->kset;
224 hotplug_ops = kset->hotplug_ops; 89 uevent_ops = kset->uevent_ops;
225 90
226 /* If the kset has a filter operation, call it. 91 /* skip the event, if the filter returns zero. */
227 Skip the event, if the filter returns zero. */ 92 if (uevent_ops && uevent_ops->filter)
228 if (hotplug_ops->filter) { 93 if (!uevent_ops->filter(kset, kobj))
229 if (!hotplug_ops->filter(kset, kobj))
230 return; 94 return;
231 }
232 95
233 pr_debug ("%s\n", __FUNCTION__); 96 /* environment index */
234 97 envp = kzalloc(NUM_ENVP * sizeof (char *), GFP_KERNEL);
235 action_string = action_to_string(action);
236 if (!action_string)
237 return;
238
239 envp = kmalloc(NUM_ENVP * sizeof (char *), GFP_KERNEL);
240 if (!envp) 98 if (!envp)
241 return; 99 return;
242 memset (envp, 0x00, NUM_ENVP * sizeof (char *));
243 100
101 /* environment values */
244 buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL); 102 buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL);
245 if (!buffer) 103 if (!buffer)
246 goto exit; 104 goto exit;
247 105
248 if (hotplug_ops->name) 106 /* complete object path */
249 name = hotplug_ops->name(kset, kobj); 107 devpath = kobject_get_path(kobj, GFP_KERNEL);
250 if (name == NULL) 108 if (!devpath)
251 name = kobject_name(&kset->kobj); 109 goto exit;
252 110
253 argv [0] = hotplug_path; 111 /* originating subsystem */
254 argv [1] = (char *)name; /* won't be changed but 'const' has to go */ 112 if (uevent_ops && uevent_ops->name)
255 argv [2] = NULL; 113 subsystem = uevent_ops->name(kset, kobj);
114 else
115 subsystem = kobject_name(&kset->kobj);
256 116
257 /* minimal command environment */ 117 /* event environemnt for helper process only */
258 envp [i++] = "HOME=/"; 118 envp[i++] = "HOME=/";
259 envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin"; 119 envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
260 120
121 /* default keys */
261 scratch = buffer; 122 scratch = buffer;
262
263 envp [i++] = scratch; 123 envp [i++] = scratch;
264 scratch += sprintf(scratch, "ACTION=%s", action_string) + 1; 124 scratch += sprintf(scratch, "ACTION=%s", action_string) + 1;
265
266 kobj_path = kobject_get_path(kobj, GFP_KERNEL);
267 if (!kobj_path)
268 goto exit;
269
270 envp [i++] = scratch; 125 envp [i++] = scratch;
271 scratch += sprintf (scratch, "DEVPATH=%s", kobj_path) + 1; 126 scratch += sprintf (scratch, "DEVPATH=%s", devpath) + 1;
272
273 envp [i++] = scratch; 127 envp [i++] = scratch;
274 scratch += sprintf(scratch, "SUBSYSTEM=%s", name) + 1; 128 scratch += sprintf(scratch, "SUBSYSTEM=%s", subsystem) + 1;
275 129
276 /* reserve space for the sequence, 130 /* just reserve the space, overwrite it after kset call has returned */
277 * put the real one in after the hotplug call */
278 envp[i++] = seq_buff = scratch; 131 envp[i++] = seq_buff = scratch;
279 scratch += strlen("SEQNUM=18446744073709551616") + 1; 132 scratch += strlen("SEQNUM=18446744073709551616") + 1;
280 133
281 if (hotplug_ops->hotplug) { 134 /* let the kset specific function add its stuff */
282 /* have the kset specific function add its stuff */ 135 if (uevent_ops && uevent_ops->uevent) {
283 retval = hotplug_ops->hotplug (kset, kobj, 136 retval = uevent_ops->uevent(kset, kobj,
284 &envp[i], NUM_ENVP - i, scratch, 137 &envp[i], NUM_ENVP - i, scratch,
285 BUFFER_SIZE - (scratch - buffer)); 138 BUFFER_SIZE - (scratch - buffer));
286 if (retval) { 139 if (retval) {
287 pr_debug ("%s - hotplug() returned %d\n", 140 pr_debug ("%s - uevent() returned %d\n",
288 __FUNCTION__, retval); 141 __FUNCTION__, retval);
289 goto exit; 142 goto exit;
290 } 143 }
291 } 144 }
292 145
146 /* we will send an event, request a new sequence number */
293 spin_lock(&sequence_lock); 147 spin_lock(&sequence_lock);
294 seq = ++hotplug_seqnum; 148 seq = ++uevent_seqnum;
295 spin_unlock(&sequence_lock); 149 spin_unlock(&sequence_lock);
296 sprintf(seq_buff, "SEQNUM=%llu", (unsigned long long)seq); 150 sprintf(seq_buff, "SEQNUM=%llu", (unsigned long long)seq);
297 151
298 pr_debug ("%s: %s %s seq=%llu %s %s %s %s %s\n", 152 /* send netlink message */
299 __FUNCTION__, argv[0], argv[1], (unsigned long long)seq, 153 if (uevent_sock) {
300 envp[0], envp[1], envp[2], envp[3], envp[4]); 154 struct sk_buff *skb;
301 155 size_t len;
302 send_uevent(action_string, kobj_path, envp, GFP_KERNEL); 156
157 /* allocate message with the maximum possible size */
158 len = strlen(action_string) + strlen(devpath) + 2;
159 skb = alloc_skb(len + BUFFER_SIZE, GFP_KERNEL);
160 if (skb) {
161 /* add header */
162 scratch = skb_put(skb, len);
163 sprintf(scratch, "%s@%s", action_string, devpath);
164
165 /* copy keys to our continuous event payload buffer */
166 for (i = 2; envp[i]; i++) {
167 len = strlen(envp[i]) + 1;
168 scratch = skb_put(skb, len);
169 strcpy(scratch, envp[i]);
170 }
171
172 NETLINK_CB(skb).dst_group = 1;
173 netlink_broadcast(uevent_sock, skb, 0, 1, GFP_KERNEL);
174 }
175 }
303 176
304 if (!hotplug_path[0]) 177 /* call uevent_helper, usually only enabled during early boot */
305 goto exit; 178 if (uevent_helper[0]) {
179 char *argv [3];
306 180
307 retval = call_usermodehelper (argv[0], argv, envp, 0); 181 argv [0] = uevent_helper;
308 if (retval) 182 argv [1] = (char *)subsystem;
309 pr_debug ("%s - call_usermodehelper returned %d\n", 183 argv [2] = NULL;
310 __FUNCTION__, retval); 184 call_usermodehelper (argv[0], argv, envp, 0);
185 }
311 186
312exit: 187exit:
313 kfree(kobj_path); 188 kfree(devpath);
314 kfree(buffer); 189 kfree(buffer);
315 kfree(envp); 190 kfree(envp);
316 return; 191 return;
317} 192}
318EXPORT_SYMBOL(kobject_hotplug); 193EXPORT_SYMBOL_GPL(kobject_uevent);
319 194
320/** 195/**
321 * add_hotplug_env_var - helper for creating hotplug environment variables 196 * add_uevent_var - helper for creating event variables
322 * @envp: Pointer to table of environment variables, as passed into 197 * @envp: Pointer to table of environment variables, as passed into
323 * hotplug() method. 198 * uevent() method.
324 * @num_envp: Number of environment variable slots available, as 199 * @num_envp: Number of environment variable slots available, as
325 * passed into hotplug() method. 200 * passed into uevent() method.
326 * @cur_index: Pointer to current index into @envp. It should be 201 * @cur_index: Pointer to current index into @envp. It should be
327 * initialized to 0 before the first call to add_hotplug_env_var(), 202 * initialized to 0 before the first call to add_uevent_var(),
328 * and will be incremented on success. 203 * and will be incremented on success.
329 * @buffer: Pointer to buffer for environment variables, as passed 204 * @buffer: Pointer to buffer for environment variables, as passed
330 * into hotplug() method. 205 * into uevent() method.
331 * @buffer_size: Length of @buffer, as passed into hotplug() method. 206 * @buffer_size: Length of @buffer, as passed into uevent() method.
332 * @cur_len: Pointer to current length of space used in @buffer. 207 * @cur_len: Pointer to current length of space used in @buffer.
333 * Should be initialized to 0 before the first call to 208 * Should be initialized to 0 before the first call to
334 * add_hotplug_env_var(), and will be incremented on success. 209 * add_uevent_var(), and will be incremented on success.
335 * @format: Format for creating environment variable (of the form 210 * @format: Format for creating environment variable (of the form
336 * "XXX=%x") for snprintf(). 211 * "XXX=%x") for snprintf().
337 * 212 *
338 * Returns 0 if environment variable was added successfully or -ENOMEM 213 * Returns 0 if environment variable was added successfully or -ENOMEM
339 * if no space was available. 214 * if no space was available.
340 */ 215 */
341int add_hotplug_env_var(char **envp, int num_envp, int *cur_index, 216int add_uevent_var(char **envp, int num_envp, int *cur_index,
342 char *buffer, int buffer_size, int *cur_len, 217 char *buffer, int buffer_size, int *cur_len,
343 const char *format, ...) 218 const char *format, ...)
344{ 219{
345 va_list args; 220 va_list args;
346 221
347 /* 222 /*
348 * We check against num_envp - 1 to make sure there is at 223 * We check against num_envp - 1 to make sure there is at
349 * least one slot left after we return, since the hotplug 224 * least one slot left after we return, since kobject_uevent()
350 * method needs to set the last slot to NULL. 225 * needs to set the last slot to NULL.
351 */ 226 */
352 if (*cur_index >= num_envp - 1) 227 if (*cur_index >= num_envp - 1)
353 return -ENOMEM; 228 return -ENOMEM;
@@ -366,6 +241,22 @@ int add_hotplug_env_var(char **envp, int num_envp, int *cur_index,
366 (*cur_index)++; 241 (*cur_index)++;
367 return 0; 242 return 0;
368} 243}
369EXPORT_SYMBOL(add_hotplug_env_var); 244EXPORT_SYMBOL_GPL(add_uevent_var);
245
246static int __init kobject_uevent_init(void)
247{
248 uevent_sock = netlink_kernel_create(NETLINK_KOBJECT_UEVENT, 1, NULL,
249 THIS_MODULE);
250
251 if (!uevent_sock) {
252 printk(KERN_ERR
253 "kobject_uevent: unable to create netlink socket!\n");
254 return -ENODEV;
255 }
256
257 return 0;
258}
259
260postcore_initcall(kobject_uevent_init);
370 261
371#endif /* CONFIG_HOTPLUG */ 262#endif /* CONFIG_HOTPLUG */