Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* Helpers for initial module or kernel cmdline parsing |
2 | Copyright (C) 2001 Rusty Russell. | |
3 | ||
4 | This program is free software; you can redistribute it and/or modify | |
5 | it under the terms of the GNU General Public License as published by | |
6 | the Free Software Foundation; either version 2 of the License, or | |
7 | (at your option) any later version. | |
8 | ||
9 | This program is distributed in the hope that it will be useful, | |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | GNU General Public License for more details. | |
13 | ||
14 | You should have received a copy of the GNU General Public License | |
15 | along with this program; if not, write to the Free Software | |
16 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
17 | */ | |
1da177e4 LT |
18 | #include <linux/kernel.h> |
19 | #include <linux/string.h> | |
20 | #include <linux/errno.h> | |
21 | #include <linux/module.h> | |
22 | #include <linux/device.h> | |
23 | #include <linux/err.h> | |
4e57b681 | 24 | #include <linux/slab.h> |
26d052bf | 25 | #include <linux/ctype.h> |
1da177e4 | 26 | |
907b29eb RR |
27 | /* Protects all parameters, and incidentally kmalloced_param list. */ |
28 | static DEFINE_MUTEX(param_lock); | |
29 | ||
a1054322 RR |
30 | /* This just allows us to keep track of which parameters are kmalloced. */ |
31 | struct kmalloced_param { | |
32 | struct list_head list; | |
33 | char val[]; | |
34 | }; | |
a1054322 RR |
35 | static LIST_HEAD(kmalloced_params); |
36 | ||
37 | static void *kmalloc_parameter(unsigned int size) | |
38 | { | |
39 | struct kmalloced_param *p; | |
40 | ||
41 | p = kmalloc(sizeof(*p) + size, GFP_KERNEL); | |
42 | if (!p) | |
43 | return NULL; | |
44 | ||
a1054322 | 45 | list_add(&p->list, &kmalloced_params); |
a1054322 RR |
46 | return p->val; |
47 | } | |
48 | ||
49 | /* Does nothing if parameter wasn't kmalloced above. */ | |
50 | static void maybe_kfree_parameter(void *param) | |
51 | { | |
52 | struct kmalloced_param *p; | |
53 | ||
a1054322 RR |
54 | list_for_each_entry(p, &kmalloced_params, list) { |
55 | if (p->val == param) { | |
56 | list_del(&p->list); | |
57 | kfree(p); | |
58 | break; | |
59 | } | |
60 | } | |
a1054322 RR |
61 | } |
62 | ||
b1e4d20c | 63 | static char dash2underscore(char c) |
1da177e4 LT |
64 | { |
65 | if (c == '-') | |
66 | return '_'; | |
67 | return c; | |
68 | } | |
69 | ||
b1e4d20c | 70 | bool parameqn(const char *a, const char *b, size_t n) |
1da177e4 | 71 | { |
b1e4d20c MS |
72 | size_t i; |
73 | ||
74 | for (i = 0; i < n; i++) { | |
75 | if (dash2underscore(a[i]) != dash2underscore(b[i])) | |
76 | return false; | |
77 | } | |
78 | return true; | |
79 | } | |
80 | ||
81 | bool parameq(const char *a, const char *b) | |
82 | { | |
83 | return parameqn(a, b, strlen(a)+1); | |
1da177e4 LT |
84 | } |
85 | ||
86 | static int parse_one(char *param, | |
87 | char *val, | |
9fb48c74 | 88 | const char *doing, |
914dcaa8 | 89 | const struct kernel_param *params, |
1da177e4 | 90 | unsigned num_params, |
026cee00 PM |
91 | s16 min_level, |
92 | s16 max_level, | |
9fb48c74 JC |
93 | int (*handle_unknown)(char *param, char *val, |
94 | const char *doing)) | |
1da177e4 LT |
95 | { |
96 | unsigned int i; | |
907b29eb | 97 | int err; |
1da177e4 LT |
98 | |
99 | /* Find parameter */ | |
100 | for (i = 0; i < num_params; i++) { | |
101 | if (parameq(param, params[i].name)) { | |
026cee00 PM |
102 | if (params[i].level < min_level |
103 | || params[i].level > max_level) | |
104 | return 0; | |
25985edc | 105 | /* No one handled NULL, so do it here. */ |
ab013c5f SR |
106 | if (!val && |
107 | !(params[i].ops->flags & KERNEL_PARAM_FL_NOARG)) | |
2e9fb995 | 108 | return -EINVAL; |
9fb48c74 JC |
109 | pr_debug("handling %s with %p\n", param, |
110 | params[i].ops->set); | |
907b29eb RR |
111 | mutex_lock(¶m_lock); |
112 | err = params[i].ops->set(val, ¶ms[i]); | |
113 | mutex_unlock(¶m_lock); | |
114 | return err; | |
1da177e4 LT |
115 | } |
116 | } | |
117 | ||
118 | if (handle_unknown) { | |
9fb48c74 JC |
119 | pr_debug("doing %s: %s='%s'\n", doing, param, val); |
120 | return handle_unknown(param, val, doing); | |
1da177e4 LT |
121 | } |
122 | ||
9fb48c74 | 123 | pr_debug("Unknown argument '%s'\n", param); |
1da177e4 LT |
124 | return -ENOENT; |
125 | } | |
126 | ||
127 | /* You can use " around spaces, but can't escape ". */ | |
128 | /* Hyphens and underscores equivalent in parameter names. */ | |
129 | static char *next_arg(char *args, char **param, char **val) | |
130 | { | |
131 | unsigned int i, equals = 0; | |
132 | int in_quote = 0, quoted = 0; | |
133 | char *next; | |
134 | ||
1da177e4 LT |
135 | if (*args == '"') { |
136 | args++; | |
137 | in_quote = 1; | |
138 | quoted = 1; | |
139 | } | |
140 | ||
141 | for (i = 0; args[i]; i++) { | |
26d052bf | 142 | if (isspace(args[i]) && !in_quote) |
1da177e4 LT |
143 | break; |
144 | if (equals == 0) { | |
145 | if (args[i] == '=') | |
146 | equals = i; | |
147 | } | |
148 | if (args[i] == '"') | |
149 | in_quote = !in_quote; | |
150 | } | |
151 | ||
152 | *param = args; | |
153 | if (!equals) | |
154 | *val = NULL; | |
155 | else { | |
156 | args[equals] = '\0'; | |
157 | *val = args + equals + 1; | |
158 | ||
159 | /* Don't include quotes in value. */ | |
160 | if (**val == '"') { | |
161 | (*val)++; | |
162 | if (args[i-1] == '"') | |
163 | args[i-1] = '\0'; | |
164 | } | |
165 | if (quoted && args[i-1] == '"') | |
166 | args[i-1] = '\0'; | |
167 | } | |
168 | ||
169 | if (args[i]) { | |
170 | args[i] = '\0'; | |
171 | next = args + i + 1; | |
172 | } else | |
173 | next = args + i; | |
f36462f0 RR |
174 | |
175 | /* Chew up trailing spaces. */ | |
e7d2860b | 176 | return skip_spaces(next); |
1da177e4 LT |
177 | } |
178 | ||
179 | /* Args looks like "foo=bar,bar2 baz=fuz wiz". */ | |
9fb48c74 | 180 | int parse_args(const char *doing, |
1da177e4 | 181 | char *args, |
914dcaa8 | 182 | const struct kernel_param *params, |
1da177e4 | 183 | unsigned num, |
026cee00 PM |
184 | s16 min_level, |
185 | s16 max_level, | |
9fb48c74 | 186 | int (*unknown)(char *param, char *val, const char *doing)) |
1da177e4 LT |
187 | { |
188 | char *param, *val; | |
189 | ||
f36462f0 | 190 | /* Chew leading spaces */ |
e7d2860b | 191 | args = skip_spaces(args); |
f36462f0 | 192 | |
1ef9eaf2 | 193 | if (*args) |
9fb48c74 JC |
194 | pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args); |
195 | ||
1da177e4 LT |
196 | while (*args) { |
197 | int ret; | |
a416aba6 | 198 | int irq_was_disabled; |
1da177e4 LT |
199 | |
200 | args = next_arg(args, ¶m, &val); | |
a416aba6 | 201 | irq_was_disabled = irqs_disabled(); |
9fb48c74 | 202 | ret = parse_one(param, val, doing, params, num, |
026cee00 | 203 | min_level, max_level, unknown); |
b5f3abf9 JC |
204 | if (irq_was_disabled && !irqs_disabled()) |
205 | pr_warn("%s: option '%s' enabled irq's!\n", | |
206 | doing, param); | |
207 | ||
1da177e4 LT |
208 | switch (ret) { |
209 | case -ENOENT: | |
b5f3abf9 | 210 | pr_err("%s: Unknown parameter `%s'\n", doing, param); |
1da177e4 LT |
211 | return ret; |
212 | case -ENOSPC: | |
b5f3abf9 | 213 | pr_err("%s: `%s' too large for parameter `%s'\n", |
9fb48c74 | 214 | doing, val ?: "", param); |
1da177e4 LT |
215 | return ret; |
216 | case 0: | |
217 | break; | |
218 | default: | |
b5f3abf9 | 219 | pr_err("%s: `%s' invalid for parameter `%s'\n", |
9fb48c74 | 220 | doing, val ?: "", param); |
1da177e4 LT |
221 | return ret; |
222 | } | |
223 | } | |
224 | ||
225 | /* All parsed OK. */ | |
226 | return 0; | |
227 | } | |
228 | ||
229 | /* Lazy bastard, eh? */ | |
230 | #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \ | |
9bbb9e5a | 231 | int param_set_##name(const char *val, const struct kernel_param *kp) \ |
1da177e4 | 232 | { \ |
1da177e4 | 233 | tmptype l; \ |
06b2a76d | 234 | int ret; \ |
1da177e4 | 235 | \ |
06b2a76d | 236 | ret = strtolfn(val, 0, &l); \ |
81c74136 SM |
237 | if (ret < 0 || ((type)l != l)) \ |
238 | return ret < 0 ? ret : -EINVAL; \ | |
1da177e4 LT |
239 | *((type *)kp->arg) = l; \ |
240 | return 0; \ | |
241 | } \ | |
9bbb9e5a | 242 | int param_get_##name(char *buffer, const struct kernel_param *kp) \ |
1da177e4 LT |
243 | { \ |
244 | return sprintf(buffer, format, *((type *)kp->arg)); \ | |
a14fe249 | 245 | } \ |
9bbb9e5a RR |
246 | struct kernel_param_ops param_ops_##name = { \ |
247 | .set = param_set_##name, \ | |
248 | .get = param_get_##name, \ | |
249 | }; \ | |
a14fe249 | 250 | EXPORT_SYMBOL(param_set_##name); \ |
9bbb9e5a RR |
251 | EXPORT_SYMBOL(param_get_##name); \ |
252 | EXPORT_SYMBOL(param_ops_##name) | |
253 | ||
1da177e4 | 254 | |
79ac6834 | 255 | STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", unsigned long, strict_strtoul); |
06b2a76d YY |
256 | STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol); |
257 | STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul); | |
258 | STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol); | |
259 | STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul); | |
260 | STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol); | |
261 | STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul); | |
1da177e4 | 262 | |
9bbb9e5a | 263 | int param_set_charp(const char *val, const struct kernel_param *kp) |
1da177e4 | 264 | { |
1da177e4 | 265 | if (strlen(val) > 1024) { |
b5f3abf9 | 266 | pr_err("%s: string parameter too long\n", kp->name); |
1da177e4 LT |
267 | return -ENOSPC; |
268 | } | |
269 | ||
a1054322 RR |
270 | maybe_kfree_parameter(*(char **)kp->arg); |
271 | ||
272 | /* This is a hack. We can't kmalloc in early boot, and we | |
e180a6b7 RR |
273 | * don't need to; this mangled commandline is preserved. */ |
274 | if (slab_is_available()) { | |
a1054322 | 275 | *(char **)kp->arg = kmalloc_parameter(strlen(val)+1); |
d553ad86 | 276 | if (!*(char **)kp->arg) |
e180a6b7 | 277 | return -ENOMEM; |
a1054322 | 278 | strcpy(*(char **)kp->arg, val); |
e180a6b7 RR |
279 | } else |
280 | *(const char **)kp->arg = val; | |
281 | ||
1da177e4 LT |
282 | return 0; |
283 | } | |
a14fe249 | 284 | EXPORT_SYMBOL(param_set_charp); |
1da177e4 | 285 | |
9bbb9e5a | 286 | int param_get_charp(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
287 | { |
288 | return sprintf(buffer, "%s", *((char **)kp->arg)); | |
289 | } | |
a14fe249 | 290 | EXPORT_SYMBOL(param_get_charp); |
1da177e4 | 291 | |
a1054322 RR |
292 | static void param_free_charp(void *arg) |
293 | { | |
294 | maybe_kfree_parameter(*((char **)arg)); | |
295 | } | |
296 | ||
9bbb9e5a RR |
297 | struct kernel_param_ops param_ops_charp = { |
298 | .set = param_set_charp, | |
299 | .get = param_get_charp, | |
a1054322 | 300 | .free = param_free_charp, |
9bbb9e5a RR |
301 | }; |
302 | EXPORT_SYMBOL(param_ops_charp); | |
303 | ||
fddd5201 | 304 | /* Actually could be a bool or an int, for historical reasons. */ |
9bbb9e5a | 305 | int param_set_bool(const char *val, const struct kernel_param *kp) |
1da177e4 LT |
306 | { |
307 | /* No equals means "set"... */ | |
308 | if (!val) val = "1"; | |
309 | ||
310 | /* One of =[yYnN01] */ | |
8b825281 | 311 | return strtobool(val, kp->arg); |
1da177e4 | 312 | } |
a14fe249 | 313 | EXPORT_SYMBOL(param_set_bool); |
1da177e4 | 314 | |
9bbb9e5a | 315 | int param_get_bool(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
316 | { |
317 | /* Y and N chosen as being relatively non-coder friendly */ | |
8b825281 | 318 | return sprintf(buffer, "%c", *(bool *)kp->arg ? 'Y' : 'N'); |
1da177e4 | 319 | } |
a14fe249 | 320 | EXPORT_SYMBOL(param_get_bool); |
1da177e4 | 321 | |
9bbb9e5a | 322 | struct kernel_param_ops param_ops_bool = { |
ab013c5f | 323 | .flags = KERNEL_PARAM_FL_NOARG, |
9bbb9e5a RR |
324 | .set = param_set_bool, |
325 | .get = param_get_bool, | |
326 | }; | |
327 | EXPORT_SYMBOL(param_ops_bool); | |
328 | ||
fddd5201 | 329 | /* This one must be bool. */ |
9bbb9e5a | 330 | int param_set_invbool(const char *val, const struct kernel_param *kp) |
1da177e4 | 331 | { |
fddd5201 RR |
332 | int ret; |
333 | bool boolval; | |
22e48eaf | 334 | struct kernel_param dummy; |
1da177e4 | 335 | |
22e48eaf | 336 | dummy.arg = &boolval; |
1da177e4 LT |
337 | ret = param_set_bool(val, &dummy); |
338 | if (ret == 0) | |
9a71af2c | 339 | *(bool *)kp->arg = !boolval; |
1da177e4 LT |
340 | return ret; |
341 | } | |
a14fe249 | 342 | EXPORT_SYMBOL(param_set_invbool); |
1da177e4 | 343 | |
9bbb9e5a | 344 | int param_get_invbool(char *buffer, const struct kernel_param *kp) |
1da177e4 | 345 | { |
9a71af2c | 346 | return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y'); |
1da177e4 | 347 | } |
a14fe249 | 348 | EXPORT_SYMBOL(param_get_invbool); |
1da177e4 | 349 | |
9bbb9e5a RR |
350 | struct kernel_param_ops param_ops_invbool = { |
351 | .set = param_set_invbool, | |
352 | .get = param_get_invbool, | |
353 | }; | |
354 | EXPORT_SYMBOL(param_ops_invbool); | |
355 | ||
69116f27 RR |
356 | int param_set_bint(const char *val, const struct kernel_param *kp) |
357 | { | |
358 | struct kernel_param boolkp; | |
359 | bool v; | |
360 | int ret; | |
361 | ||
362 | /* Match bool exactly, by re-using it. */ | |
363 | boolkp = *kp; | |
364 | boolkp.arg = &v; | |
69116f27 RR |
365 | |
366 | ret = param_set_bool(val, &boolkp); | |
367 | if (ret == 0) | |
368 | *(int *)kp->arg = v; | |
369 | return ret; | |
370 | } | |
371 | EXPORT_SYMBOL(param_set_bint); | |
372 | ||
373 | struct kernel_param_ops param_ops_bint = { | |
ab013c5f | 374 | .flags = KERNEL_PARAM_FL_NOARG, |
69116f27 RR |
375 | .set = param_set_bint, |
376 | .get = param_get_int, | |
377 | }; | |
378 | EXPORT_SYMBOL(param_ops_bint); | |
379 | ||
9730b5b0 | 380 | /* We break the rule and mangle the string. */ |
9871728b AB |
381 | static int param_array(const char *name, |
382 | const char *val, | |
383 | unsigned int min, unsigned int max, | |
384 | void *elem, int elemsize, | |
9bbb9e5a | 385 | int (*set)(const char *, const struct kernel_param *kp), |
026cee00 | 386 | s16 level, |
eb38a996 | 387 | unsigned int *num) |
1da177e4 LT |
388 | { |
389 | int ret; | |
390 | struct kernel_param kp; | |
391 | char save; | |
392 | ||
393 | /* Get the name right for errors. */ | |
394 | kp.name = name; | |
395 | kp.arg = elem; | |
026cee00 | 396 | kp.level = level; |
1da177e4 | 397 | |
1da177e4 LT |
398 | *num = 0; |
399 | /* We expect a comma-separated list of values. */ | |
400 | do { | |
401 | int len; | |
402 | ||
403 | if (*num == max) { | |
b5f3abf9 | 404 | pr_err("%s: can only take %i arguments\n", name, max); |
1da177e4 LT |
405 | return -EINVAL; |
406 | } | |
407 | len = strcspn(val, ","); | |
408 | ||
409 | /* nul-terminate and parse */ | |
410 | save = val[len]; | |
411 | ((char *)val)[len] = '\0'; | |
907b29eb | 412 | BUG_ON(!mutex_is_locked(¶m_lock)); |
1da177e4 LT |
413 | ret = set(val, &kp); |
414 | ||
415 | if (ret != 0) | |
416 | return ret; | |
417 | kp.arg += elemsize; | |
418 | val += len+1; | |
419 | (*num)++; | |
420 | } while (save == ','); | |
421 | ||
422 | if (*num < min) { | |
b5f3abf9 | 423 | pr_err("%s: needs at least %i arguments\n", name, min); |
1da177e4 LT |
424 | return -EINVAL; |
425 | } | |
426 | return 0; | |
427 | } | |
428 | ||
9bbb9e5a | 429 | static int param_array_set(const char *val, const struct kernel_param *kp) |
1da177e4 | 430 | { |
22e48eaf | 431 | const struct kparam_array *arr = kp->arr; |
31143a12 | 432 | unsigned int temp_num; |
1da177e4 LT |
433 | |
434 | return param_array(kp->name, val, 1, arr->max, arr->elem, | |
026cee00 | 435 | arr->elemsize, arr->ops->set, kp->level, |
3c7d76e3 | 436 | arr->num ?: &temp_num); |
1da177e4 LT |
437 | } |
438 | ||
9bbb9e5a | 439 | static int param_array_get(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
440 | { |
441 | int i, off, ret; | |
22e48eaf | 442 | const struct kparam_array *arr = kp->arr; |
1da177e4 LT |
443 | struct kernel_param p; |
444 | ||
445 | p = *kp; | |
446 | for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) { | |
447 | if (i) | |
448 | buffer[off++] = ','; | |
449 | p.arg = arr->elem + arr->elemsize * i; | |
907b29eb | 450 | BUG_ON(!mutex_is_locked(¶m_lock)); |
9bbb9e5a | 451 | ret = arr->ops->get(buffer + off, &p); |
1da177e4 LT |
452 | if (ret < 0) |
453 | return ret; | |
454 | off += ret; | |
455 | } | |
456 | buffer[off] = '\0'; | |
457 | return off; | |
458 | } | |
459 | ||
e6df34a4 RR |
460 | static void param_array_free(void *arg) |
461 | { | |
462 | unsigned int i; | |
463 | const struct kparam_array *arr = arg; | |
464 | ||
465 | if (arr->ops->free) | |
466 | for (i = 0; i < (arr->num ? *arr->num : arr->max); i++) | |
467 | arr->ops->free(arr->elem + arr->elemsize * i); | |
468 | } | |
469 | ||
9bbb9e5a RR |
470 | struct kernel_param_ops param_array_ops = { |
471 | .set = param_array_set, | |
472 | .get = param_array_get, | |
e6df34a4 | 473 | .free = param_array_free, |
9bbb9e5a RR |
474 | }; |
475 | EXPORT_SYMBOL(param_array_ops); | |
476 | ||
477 | int param_set_copystring(const char *val, const struct kernel_param *kp) | |
1da177e4 | 478 | { |
22e48eaf | 479 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
480 | |
481 | if (strlen(val)+1 > kps->maxlen) { | |
b5f3abf9 | 482 | pr_err("%s: string doesn't fit in %u chars.\n", |
1da177e4 LT |
483 | kp->name, kps->maxlen-1); |
484 | return -ENOSPC; | |
485 | } | |
486 | strcpy(kps->string, val); | |
487 | return 0; | |
488 | } | |
a14fe249 | 489 | EXPORT_SYMBOL(param_set_copystring); |
1da177e4 | 490 | |
9bbb9e5a | 491 | int param_get_string(char *buffer, const struct kernel_param *kp) |
1da177e4 | 492 | { |
22e48eaf | 493 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
494 | return strlcpy(buffer, kps->string, kps->maxlen); |
495 | } | |
a14fe249 | 496 | EXPORT_SYMBOL(param_get_string); |
1da177e4 | 497 | |
9bbb9e5a RR |
498 | struct kernel_param_ops param_ops_string = { |
499 | .set = param_set_copystring, | |
500 | .get = param_get_string, | |
501 | }; | |
502 | EXPORT_SYMBOL(param_ops_string); | |
503 | ||
1da177e4 | 504 | /* sysfs output in /sys/modules/XYZ/parameters/ */ |
350f8258 EY |
505 | #define to_module_attr(n) container_of(n, struct module_attribute, attr) |
506 | #define to_module_kobject(n) container_of(n, struct module_kobject, kobj) | |
1da177e4 LT |
507 | |
508 | extern struct kernel_param __start___param[], __stop___param[]; | |
509 | ||
1da177e4 LT |
510 | struct param_attribute |
511 | { | |
512 | struct module_attribute mattr; | |
9bbb9e5a | 513 | const struct kernel_param *param; |
1da177e4 LT |
514 | }; |
515 | ||
516 | struct module_param_attrs | |
517 | { | |
9b473de8 | 518 | unsigned int num; |
1da177e4 LT |
519 | struct attribute_group grp; |
520 | struct param_attribute attrs[0]; | |
521 | }; | |
522 | ||
ef665c1a | 523 | #ifdef CONFIG_SYSFS |
350f8258 | 524 | #define to_param_attr(n) container_of(n, struct param_attribute, mattr) |
1da177e4 LT |
525 | |
526 | static ssize_t param_attr_show(struct module_attribute *mattr, | |
4befb026 | 527 | struct module_kobject *mk, char *buf) |
1da177e4 LT |
528 | { |
529 | int count; | |
530 | struct param_attribute *attribute = to_param_attr(mattr); | |
531 | ||
9bbb9e5a | 532 | if (!attribute->param->ops->get) |
1da177e4 LT |
533 | return -EPERM; |
534 | ||
907b29eb | 535 | mutex_lock(¶m_lock); |
9bbb9e5a | 536 | count = attribute->param->ops->get(buf, attribute->param); |
907b29eb | 537 | mutex_unlock(¶m_lock); |
1da177e4 LT |
538 | if (count > 0) { |
539 | strcat(buf, "\n"); | |
540 | ++count; | |
541 | } | |
542 | return count; | |
543 | } | |
544 | ||
545 | /* sysfs always hands a nul-terminated string in buf. We rely on that. */ | |
546 | static ssize_t param_attr_store(struct module_attribute *mattr, | |
4befb026 | 547 | struct module_kobject *km, |
1da177e4 LT |
548 | const char *buf, size_t len) |
549 | { | |
550 | int err; | |
551 | struct param_attribute *attribute = to_param_attr(mattr); | |
552 | ||
9bbb9e5a | 553 | if (!attribute->param->ops->set) |
1da177e4 LT |
554 | return -EPERM; |
555 | ||
907b29eb | 556 | mutex_lock(¶m_lock); |
9bbb9e5a | 557 | err = attribute->param->ops->set(buf, attribute->param); |
907b29eb | 558 | mutex_unlock(¶m_lock); |
1da177e4 LT |
559 | if (!err) |
560 | return len; | |
561 | return err; | |
562 | } | |
ef665c1a | 563 | #endif |
1da177e4 LT |
564 | |
565 | #ifdef CONFIG_MODULES | |
566 | #define __modinit | |
567 | #else | |
568 | #define __modinit __init | |
569 | #endif | |
570 | ||
ef665c1a | 571 | #ifdef CONFIG_SYSFS |
907b29eb RR |
572 | void __kernel_param_lock(void) |
573 | { | |
574 | mutex_lock(¶m_lock); | |
575 | } | |
576 | EXPORT_SYMBOL(__kernel_param_lock); | |
577 | ||
578 | void __kernel_param_unlock(void) | |
579 | { | |
580 | mutex_unlock(¶m_lock); | |
581 | } | |
582 | EXPORT_SYMBOL(__kernel_param_unlock); | |
583 | ||
1da177e4 | 584 | /* |
9b473de8 RR |
585 | * add_sysfs_param - add a parameter to sysfs |
586 | * @mk: struct module_kobject | |
587 | * @kparam: the actual parameter definition to add to sysfs | |
588 | * @name: name of parameter | |
1da177e4 | 589 | * |
9b473de8 RR |
590 | * Create a kobject if for a (per-module) parameter if mp NULL, and |
591 | * create file in sysfs. Returns an error on out of memory. Always cleans up | |
592 | * if there's an error. | |
1da177e4 | 593 | */ |
9b473de8 | 594 | static __modinit int add_sysfs_param(struct module_kobject *mk, |
9bbb9e5a | 595 | const struct kernel_param *kp, |
9b473de8 | 596 | const char *name) |
1da177e4 | 597 | { |
9b473de8 RR |
598 | struct module_param_attrs *new; |
599 | struct attribute **attrs; | |
600 | int err, num; | |
601 | ||
602 | /* We don't bother calling this with invisible parameters. */ | |
603 | BUG_ON(!kp->perm); | |
604 | ||
605 | if (!mk->mp) { | |
606 | num = 0; | |
607 | attrs = NULL; | |
608 | } else { | |
609 | num = mk->mp->num; | |
610 | attrs = mk->mp->grp.attrs; | |
1da177e4 LT |
611 | } |
612 | ||
9b473de8 RR |
613 | /* Enlarge. */ |
614 | new = krealloc(mk->mp, | |
615 | sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1), | |
616 | GFP_KERNEL); | |
617 | if (!new) { | |
63662139 | 618 | kfree(attrs); |
9b473de8 RR |
619 | err = -ENOMEM; |
620 | goto fail; | |
621 | } | |
63662139 DW |
622 | /* Despite looking like the typical realloc() bug, this is safe. |
623 | * We *want* the old 'attrs' to be freed either way, and we'll store | |
624 | * the new one in the success case. */ | |
9b473de8 RR |
625 | attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL); |
626 | if (!attrs) { | |
627 | err = -ENOMEM; | |
628 | goto fail_free_new; | |
629 | } | |
1da177e4 | 630 | |
9b473de8 RR |
631 | /* Sysfs wants everything zeroed. */ |
632 | memset(new, 0, sizeof(*new)); | |
633 | memset(&new->attrs[num], 0, sizeof(new->attrs[num])); | |
634 | memset(&attrs[num], 0, sizeof(attrs[num])); | |
635 | new->grp.name = "parameters"; | |
636 | new->grp.attrs = attrs; | |
637 | ||
638 | /* Tack new one on the end. */ | |
a07e4156 | 639 | sysfs_attr_init(&new->attrs[num].mattr.attr); |
9b473de8 RR |
640 | new->attrs[num].param = kp; |
641 | new->attrs[num].mattr.show = param_attr_show; | |
642 | new->attrs[num].mattr.store = param_attr_store; | |
643 | new->attrs[num].mattr.attr.name = (char *)name; | |
644 | new->attrs[num].mattr.attr.mode = kp->perm; | |
645 | new->num = num+1; | |
646 | ||
647 | /* Fix up all the pointers, since krealloc can move us */ | |
648 | for (num = 0; num < new->num; num++) | |
649 | new->grp.attrs[num] = &new->attrs[num].mattr.attr; | |
650 | new->grp.attrs[num] = NULL; | |
651 | ||
652 | mk->mp = new; | |
653 | return 0; | |
1da177e4 | 654 | |
9b473de8 RR |
655 | fail_free_new: |
656 | kfree(new); | |
657 | fail: | |
658 | mk->mp = NULL; | |
659 | return err; | |
660 | } | |
1da177e4 | 661 | |
d2441183 | 662 | #ifdef CONFIG_MODULES |
9b473de8 RR |
663 | static void free_module_param_attrs(struct module_kobject *mk) |
664 | { | |
665 | kfree(mk->mp->grp.attrs); | |
666 | kfree(mk->mp); | |
667 | mk->mp = NULL; | |
1da177e4 LT |
668 | } |
669 | ||
1da177e4 LT |
670 | /* |
671 | * module_param_sysfs_setup - setup sysfs support for one module | |
672 | * @mod: module | |
673 | * @kparam: module parameters (array) | |
674 | * @num_params: number of module parameters | |
675 | * | |
9b473de8 RR |
676 | * Adds sysfs entries for module parameters under |
677 | * /sys/module/[mod->name]/parameters/ | |
1da177e4 LT |
678 | */ |
679 | int module_param_sysfs_setup(struct module *mod, | |
9bbb9e5a | 680 | const struct kernel_param *kparam, |
1da177e4 LT |
681 | unsigned int num_params) |
682 | { | |
9b473de8 RR |
683 | int i, err; |
684 | bool params = false; | |
685 | ||
686 | for (i = 0; i < num_params; i++) { | |
687 | if (kparam[i].perm == 0) | |
688 | continue; | |
689 | err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name); | |
690 | if (err) | |
691 | return err; | |
692 | params = true; | |
693 | } | |
1da177e4 | 694 | |
9b473de8 RR |
695 | if (!params) |
696 | return 0; | |
1da177e4 | 697 | |
9b473de8 RR |
698 | /* Create the param group. */ |
699 | err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
700 | if (err) | |
701 | free_module_param_attrs(&mod->mkobj); | |
702 | return err; | |
1da177e4 LT |
703 | } |
704 | ||
705 | /* | |
706 | * module_param_sysfs_remove - remove sysfs support for one module | |
707 | * @mod: module | |
708 | * | |
709 | * Remove sysfs entries for module parameters and the corresponding | |
710 | * kobject. | |
711 | */ | |
712 | void module_param_sysfs_remove(struct module *mod) | |
713 | { | |
9b473de8 RR |
714 | if (mod->mkobj.mp) { |
715 | sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
1da177e4 LT |
716 | /* We are positive that no one is using any param |
717 | * attrs at this point. Deallocate immediately. */ | |
9b473de8 | 718 | free_module_param_attrs(&mod->mkobj); |
1da177e4 LT |
719 | } |
720 | } | |
721 | #endif | |
722 | ||
e180a6b7 RR |
723 | void destroy_params(const struct kernel_param *params, unsigned num) |
724 | { | |
e6df34a4 RR |
725 | unsigned int i; |
726 | ||
727 | for (i = 0; i < num; i++) | |
728 | if (params[i].ops->free) | |
729 | params[i].ops->free(params[i].arg); | |
e180a6b7 RR |
730 | } |
731 | ||
e94965ed | 732 | static struct module_kobject * __init locate_module_kobject(const char *name) |
1da177e4 LT |
733 | { |
734 | struct module_kobject *mk; | |
9b473de8 RR |
735 | struct kobject *kobj; |
736 | int err; | |
1da177e4 | 737 | |
9b473de8 RR |
738 | kobj = kset_find_obj(module_kset, name); |
739 | if (kobj) { | |
9b473de8 | 740 | mk = to_module_kobject(kobj); |
9b473de8 RR |
741 | } else { |
742 | mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL); | |
743 | BUG_ON(!mk); | |
744 | ||
745 | mk->mod = THIS_MODULE; | |
746 | mk->kobj.kset = module_kset; | |
747 | err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL, | |
748 | "%s", name); | |
88bfa324 KS |
749 | #ifdef CONFIG_MODULES |
750 | if (!err) | |
751 | err = sysfs_create_file(&mk->kobj, &module_uevent.attr); | |
752 | #endif | |
9b473de8 RR |
753 | if (err) { |
754 | kobject_put(&mk->kobj); | |
b5f3abf9 | 755 | pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n", |
e94965ed | 756 | name, err); |
e94965ed | 757 | return NULL; |
9b473de8 | 758 | } |
e94965ed DT |
759 | |
760 | /* So that we hold reference in both cases. */ | |
9b473de8 | 761 | kobject_get(&mk->kobj); |
74c5b597 | 762 | } |
9b473de8 | 763 | |
e94965ed DT |
764 | return mk; |
765 | } | |
766 | ||
767 | static void __init kernel_add_sysfs_param(const char *name, | |
768 | struct kernel_param *kparam, | |
769 | unsigned int name_skip) | |
770 | { | |
771 | struct module_kobject *mk; | |
772 | int err; | |
773 | ||
774 | mk = locate_module_kobject(name); | |
775 | if (!mk) | |
776 | return; | |
777 | ||
778 | /* We need to remove old parameters before adding more. */ | |
779 | if (mk->mp) | |
780 | sysfs_remove_group(&mk->kobj, &mk->mp->grp); | |
781 | ||
9b473de8 RR |
782 | /* These should not fail at boot. */ |
783 | err = add_sysfs_param(mk, kparam, kparam->name + name_skip); | |
784 | BUG_ON(err); | |
785 | err = sysfs_create_group(&mk->kobj, &mk->mp->grp); | |
786 | BUG_ON(err); | |
f30c53a8 | 787 | kobject_uevent(&mk->kobj, KOBJ_ADD); |
9b473de8 | 788 | kobject_put(&mk->kobj); |
1da177e4 LT |
789 | } |
790 | ||
791 | /* | |
b634d130 | 792 | * param_sysfs_builtin - add sysfs parameters for built-in modules |
1da177e4 LT |
793 | * |
794 | * Add module_parameters to sysfs for "modules" built into the kernel. | |
795 | * | |
796 | * The "module" name (KBUILD_MODNAME) is stored before a dot, the | |
797 | * "parameter" name is stored behind a dot in kernel_param->name. So, | |
798 | * extract the "module" name for all built-in kernel_param-eters, | |
9b473de8 | 799 | * and for all who have the same, call kernel_add_sysfs_param. |
1da177e4 LT |
800 | */ |
801 | static void __init param_sysfs_builtin(void) | |
802 | { | |
9b473de8 RR |
803 | struct kernel_param *kp; |
804 | unsigned int name_len; | |
805 | char modname[MODULE_NAME_LEN]; | |
1da177e4 | 806 | |
9b473de8 | 807 | for (kp = __start___param; kp < __stop___param; kp++) { |
1da177e4 LT |
808 | char *dot; |
809 | ||
9b473de8 RR |
810 | if (kp->perm == 0) |
811 | continue; | |
1da177e4 | 812 | |
730b69d2 | 813 | dot = strchr(kp->name, '.'); |
1da177e4 | 814 | if (!dot) { |
67e67cea RR |
815 | /* This happens for core_param() */ |
816 | strcpy(modname, "kernel"); | |
817 | name_len = 0; | |
818 | } else { | |
819 | name_len = dot - kp->name + 1; | |
820 | strlcpy(modname, kp->name, name_len); | |
1da177e4 | 821 | } |
67e67cea | 822 | kernel_add_sysfs_param(modname, kp, name_len); |
1da177e4 | 823 | } |
1da177e4 LT |
824 | } |
825 | ||
e94965ed | 826 | ssize_t __modver_version_show(struct module_attribute *mattr, |
4befb026 | 827 | struct module_kobject *mk, char *buf) |
e94965ed DT |
828 | { |
829 | struct module_version_attribute *vattr = | |
830 | container_of(mattr, struct module_version_attribute, mattr); | |
831 | ||
832 | return sprintf(buf, "%s\n", vattr->version); | |
833 | } | |
834 | ||
b4bc8428 DT |
835 | extern const struct module_version_attribute *__start___modver[]; |
836 | extern const struct module_version_attribute *__stop___modver[]; | |
e94965ed DT |
837 | |
838 | static void __init version_sysfs_builtin(void) | |
839 | { | |
b4bc8428 | 840 | const struct module_version_attribute **p; |
e94965ed DT |
841 | struct module_kobject *mk; |
842 | int err; | |
843 | ||
b4bc8428 DT |
844 | for (p = __start___modver; p < __stop___modver; p++) { |
845 | const struct module_version_attribute *vattr = *p; | |
846 | ||
e94965ed DT |
847 | mk = locate_module_kobject(vattr->module_name); |
848 | if (mk) { | |
849 | err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr); | |
850 | kobject_uevent(&mk->kobj, KOBJ_ADD); | |
851 | kobject_put(&mk->kobj); | |
852 | } | |
853 | } | |
854 | } | |
1da177e4 LT |
855 | |
856 | /* module-related sysfs stuff */ | |
1da177e4 | 857 | |
1da177e4 LT |
858 | static ssize_t module_attr_show(struct kobject *kobj, |
859 | struct attribute *attr, | |
860 | char *buf) | |
861 | { | |
862 | struct module_attribute *attribute; | |
863 | struct module_kobject *mk; | |
864 | int ret; | |
865 | ||
866 | attribute = to_module_attr(attr); | |
867 | mk = to_module_kobject(kobj); | |
868 | ||
869 | if (!attribute->show) | |
70f2817a | 870 | return -EIO; |
1da177e4 | 871 | |
4befb026 | 872 | ret = attribute->show(attribute, mk, buf); |
1da177e4 | 873 | |
1da177e4 LT |
874 | return ret; |
875 | } | |
876 | ||
877 | static ssize_t module_attr_store(struct kobject *kobj, | |
878 | struct attribute *attr, | |
879 | const char *buf, size_t len) | |
880 | { | |
881 | struct module_attribute *attribute; | |
882 | struct module_kobject *mk; | |
883 | int ret; | |
884 | ||
885 | attribute = to_module_attr(attr); | |
886 | mk = to_module_kobject(kobj); | |
887 | ||
888 | if (!attribute->store) | |
70f2817a | 889 | return -EIO; |
1da177e4 | 890 | |
4befb026 | 891 | ret = attribute->store(attribute, mk, buf, len); |
1da177e4 | 892 | |
1da177e4 LT |
893 | return ret; |
894 | } | |
895 | ||
52cf25d0 | 896 | static const struct sysfs_ops module_sysfs_ops = { |
1da177e4 LT |
897 | .show = module_attr_show, |
898 | .store = module_attr_store, | |
899 | }; | |
900 | ||
270a6c4c KS |
901 | static int uevent_filter(struct kset *kset, struct kobject *kobj) |
902 | { | |
903 | struct kobj_type *ktype = get_ktype(kobj); | |
904 | ||
905 | if (ktype == &module_ktype) | |
906 | return 1; | |
907 | return 0; | |
908 | } | |
909 | ||
9cd43611 | 910 | static const struct kset_uevent_ops module_uevent_ops = { |
270a6c4c KS |
911 | .filter = uevent_filter, |
912 | }; | |
913 | ||
7405c1e1 | 914 | struct kset *module_kset; |
823bccfc | 915 | int module_sysfs_initialized; |
1da177e4 | 916 | |
7405c1e1 | 917 | struct kobj_type module_ktype = { |
1da177e4 LT |
918 | .sysfs_ops = &module_sysfs_ops, |
919 | }; | |
920 | ||
1da177e4 LT |
921 | /* |
922 | * param_sysfs_init - wrapper for built-in params support | |
923 | */ | |
924 | static int __init param_sysfs_init(void) | |
925 | { | |
7405c1e1 GKH |
926 | module_kset = kset_create_and_add("module", &module_uevent_ops, NULL); |
927 | if (!module_kset) { | |
928 | printk(KERN_WARNING "%s (%d): error creating kset\n", | |
929 | __FILE__, __LINE__); | |
930 | return -ENOMEM; | |
d8c7649e | 931 | } |
823bccfc | 932 | module_sysfs_initialized = 1; |
1da177e4 | 933 | |
e94965ed | 934 | version_sysfs_builtin(); |
1da177e4 LT |
935 | param_sysfs_builtin(); |
936 | ||
937 | return 0; | |
938 | } | |
d10be6d1 | 939 | subsys_initcall(param_sysfs_init); |
1da177e4 | 940 | |
7405c1e1 | 941 | #endif /* CONFIG_SYSFS */ |