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> | |
63a12d9d | 22 | #include <linux/moduleparam.h> |
1da177e4 LT |
23 | #include <linux/device.h> |
24 | #include <linux/err.h> | |
4e57b681 | 25 | #include <linux/slab.h> |
26d052bf | 26 | #include <linux/ctype.h> |
1da177e4 | 27 | |
907b29eb RR |
28 | /* Protects all parameters, and incidentally kmalloced_param list. */ |
29 | static DEFINE_MUTEX(param_lock); | |
30 | ||
a1054322 RR |
31 | /* This just allows us to keep track of which parameters are kmalloced. */ |
32 | struct kmalloced_param { | |
33 | struct list_head list; | |
34 | char val[]; | |
35 | }; | |
a1054322 RR |
36 | static LIST_HEAD(kmalloced_params); |
37 | ||
38 | static void *kmalloc_parameter(unsigned int size) | |
39 | { | |
40 | struct kmalloced_param *p; | |
41 | ||
42 | p = kmalloc(sizeof(*p) + size, GFP_KERNEL); | |
43 | if (!p) | |
44 | return NULL; | |
45 | ||
a1054322 | 46 | list_add(&p->list, &kmalloced_params); |
a1054322 RR |
47 | return p->val; |
48 | } | |
49 | ||
50 | /* Does nothing if parameter wasn't kmalloced above. */ | |
51 | static void maybe_kfree_parameter(void *param) | |
52 | { | |
53 | struct kmalloced_param *p; | |
54 | ||
a1054322 RR |
55 | list_for_each_entry(p, &kmalloced_params, list) { |
56 | if (p->val == param) { | |
57 | list_del(&p->list); | |
58 | kfree(p); | |
59 | break; | |
60 | } | |
61 | } | |
a1054322 RR |
62 | } |
63 | ||
b1e4d20c | 64 | static char dash2underscore(char c) |
1da177e4 LT |
65 | { |
66 | if (c == '-') | |
67 | return '_'; | |
68 | return c; | |
69 | } | |
70 | ||
b1e4d20c | 71 | bool parameqn(const char *a, const char *b, size_t n) |
1da177e4 | 72 | { |
b1e4d20c MS |
73 | size_t i; |
74 | ||
75 | for (i = 0; i < n; i++) { | |
76 | if (dash2underscore(a[i]) != dash2underscore(b[i])) | |
77 | return false; | |
78 | } | |
79 | return true; | |
80 | } | |
81 | ||
82 | bool parameq(const char *a, const char *b) | |
83 | { | |
84 | return parameqn(a, b, strlen(a)+1); | |
1da177e4 LT |
85 | } |
86 | ||
7a486d37 RR |
87 | static void param_check_unsafe(const struct kernel_param *kp) |
88 | { | |
89 | if (kp->flags & KERNEL_PARAM_FL_UNSAFE) { | |
90 | pr_warn("Setting dangerous option %s - tainting kernel\n", | |
91 | kp->name); | |
92 | add_taint(TAINT_USER, LOCKDEP_STILL_OK); | |
93 | } | |
94 | } | |
95 | ||
1da177e4 LT |
96 | static int parse_one(char *param, |
97 | char *val, | |
9fb48c74 | 98 | const char *doing, |
914dcaa8 | 99 | const struct kernel_param *params, |
1da177e4 | 100 | unsigned num_params, |
026cee00 PM |
101 | s16 min_level, |
102 | s16 max_level, | |
9fb48c74 JC |
103 | int (*handle_unknown)(char *param, char *val, |
104 | const char *doing)) | |
1da177e4 LT |
105 | { |
106 | unsigned int i; | |
907b29eb | 107 | int err; |
1da177e4 LT |
108 | |
109 | /* Find parameter */ | |
110 | for (i = 0; i < num_params; i++) { | |
111 | if (parameq(param, params[i].name)) { | |
026cee00 PM |
112 | if (params[i].level < min_level |
113 | || params[i].level > max_level) | |
114 | return 0; | |
25985edc | 115 | /* No one handled NULL, so do it here. */ |
ab013c5f | 116 | if (!val && |
6a4c2643 | 117 | !(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG)) |
2e9fb995 | 118 | return -EINVAL; |
9fb48c74 JC |
119 | pr_debug("handling %s with %p\n", param, |
120 | params[i].ops->set); | |
907b29eb | 121 | mutex_lock(¶m_lock); |
7a486d37 | 122 | param_check_unsafe(¶ms[i]); |
907b29eb RR |
123 | err = params[i].ops->set(val, ¶ms[i]); |
124 | mutex_unlock(¶m_lock); | |
125 | return err; | |
1da177e4 LT |
126 | } |
127 | } | |
128 | ||
129 | if (handle_unknown) { | |
9fb48c74 JC |
130 | pr_debug("doing %s: %s='%s'\n", doing, param, val); |
131 | return handle_unknown(param, val, doing); | |
1da177e4 LT |
132 | } |
133 | ||
9fb48c74 | 134 | pr_debug("Unknown argument '%s'\n", param); |
1da177e4 LT |
135 | return -ENOENT; |
136 | } | |
137 | ||
138 | /* You can use " around spaces, but can't escape ". */ | |
139 | /* Hyphens and underscores equivalent in parameter names. */ | |
140 | static char *next_arg(char *args, char **param, char **val) | |
141 | { | |
142 | unsigned int i, equals = 0; | |
143 | int in_quote = 0, quoted = 0; | |
144 | char *next; | |
145 | ||
1da177e4 LT |
146 | if (*args == '"') { |
147 | args++; | |
148 | in_quote = 1; | |
149 | quoted = 1; | |
150 | } | |
151 | ||
152 | for (i = 0; args[i]; i++) { | |
26d052bf | 153 | if (isspace(args[i]) && !in_quote) |
1da177e4 LT |
154 | break; |
155 | if (equals == 0) { | |
156 | if (args[i] == '=') | |
157 | equals = i; | |
158 | } | |
159 | if (args[i] == '"') | |
160 | in_quote = !in_quote; | |
161 | } | |
162 | ||
163 | *param = args; | |
164 | if (!equals) | |
165 | *val = NULL; | |
166 | else { | |
167 | args[equals] = '\0'; | |
168 | *val = args + equals + 1; | |
169 | ||
170 | /* Don't include quotes in value. */ | |
171 | if (**val == '"') { | |
172 | (*val)++; | |
173 | if (args[i-1] == '"') | |
174 | args[i-1] = '\0'; | |
175 | } | |
176 | if (quoted && args[i-1] == '"') | |
177 | args[i-1] = '\0'; | |
178 | } | |
179 | ||
180 | if (args[i]) { | |
181 | args[i] = '\0'; | |
182 | next = args + i + 1; | |
183 | } else | |
184 | next = args + i; | |
f36462f0 RR |
185 | |
186 | /* Chew up trailing spaces. */ | |
e7d2860b | 187 | return skip_spaces(next); |
1da177e4 LT |
188 | } |
189 | ||
190 | /* Args looks like "foo=bar,bar2 baz=fuz wiz". */ | |
51e158c1 RR |
191 | char *parse_args(const char *doing, |
192 | char *args, | |
193 | const struct kernel_param *params, | |
194 | unsigned num, | |
195 | s16 min_level, | |
196 | s16 max_level, | |
197 | int (*unknown)(char *param, char *val, const char *doing)) | |
1da177e4 LT |
198 | { |
199 | char *param, *val; | |
200 | ||
f36462f0 | 201 | /* Chew leading spaces */ |
e7d2860b | 202 | args = skip_spaces(args); |
f36462f0 | 203 | |
1ef9eaf2 | 204 | if (*args) |
9fb48c74 JC |
205 | pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args); |
206 | ||
1da177e4 LT |
207 | while (*args) { |
208 | int ret; | |
a416aba6 | 209 | int irq_was_disabled; |
1da177e4 LT |
210 | |
211 | args = next_arg(args, ¶m, &val); | |
51e158c1 RR |
212 | /* Stop at -- */ |
213 | if (!val && strcmp(param, "--") == 0) | |
214 | return args; | |
a416aba6 | 215 | irq_was_disabled = irqs_disabled(); |
9fb48c74 | 216 | ret = parse_one(param, val, doing, params, num, |
026cee00 | 217 | min_level, max_level, unknown); |
b5f3abf9 JC |
218 | if (irq_was_disabled && !irqs_disabled()) |
219 | pr_warn("%s: option '%s' enabled irq's!\n", | |
220 | doing, param); | |
221 | ||
1da177e4 LT |
222 | switch (ret) { |
223 | case -ENOENT: | |
b5f3abf9 | 224 | pr_err("%s: Unknown parameter `%s'\n", doing, param); |
51e158c1 | 225 | return ERR_PTR(ret); |
1da177e4 | 226 | case -ENOSPC: |
b5f3abf9 | 227 | pr_err("%s: `%s' too large for parameter `%s'\n", |
9fb48c74 | 228 | doing, val ?: "", param); |
51e158c1 | 229 | return ERR_PTR(ret); |
1da177e4 LT |
230 | case 0: |
231 | break; | |
232 | default: | |
b5f3abf9 | 233 | pr_err("%s: `%s' invalid for parameter `%s'\n", |
9fb48c74 | 234 | doing, val ?: "", param); |
51e158c1 | 235 | return ERR_PTR(ret); |
1da177e4 LT |
236 | } |
237 | } | |
238 | ||
239 | /* All parsed OK. */ | |
51e158c1 | 240 | return NULL; |
1da177e4 LT |
241 | } |
242 | ||
243 | /* Lazy bastard, eh? */ | |
88a88b32 | 244 | #define STANDARD_PARAM_DEF(name, type, format, strtolfn) \ |
9bbb9e5a | 245 | int param_set_##name(const char *val, const struct kernel_param *kp) \ |
1da177e4 | 246 | { \ |
88a88b32 | 247 | return strtolfn(val, 0, (type *)kp->arg); \ |
1da177e4 | 248 | } \ |
9bbb9e5a | 249 | int param_get_##name(char *buffer, const struct kernel_param *kp) \ |
1da177e4 | 250 | { \ |
f4940ab7 CG |
251 | return scnprintf(buffer, PAGE_SIZE, format, \ |
252 | *((type *)kp->arg)); \ | |
a14fe249 | 253 | } \ |
9bbb9e5a RR |
254 | struct kernel_param_ops param_ops_##name = { \ |
255 | .set = param_set_##name, \ | |
256 | .get = param_get_##name, \ | |
257 | }; \ | |
a14fe249 | 258 | EXPORT_SYMBOL(param_set_##name); \ |
9bbb9e5a RR |
259 | EXPORT_SYMBOL(param_get_##name); \ |
260 | EXPORT_SYMBOL(param_ops_##name) | |
261 | ||
1da177e4 | 262 | |
88a88b32 FC |
263 | STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8); |
264 | STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16); | |
265 | STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16); | |
266 | STANDARD_PARAM_DEF(int, int, "%i", kstrtoint); | |
267 | STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint); | |
268 | STANDARD_PARAM_DEF(long, long, "%li", kstrtol); | |
269 | STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul); | |
b4210b81 | 270 | STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull); |
1da177e4 | 271 | |
9bbb9e5a | 272 | int param_set_charp(const char *val, const struct kernel_param *kp) |
1da177e4 | 273 | { |
1da177e4 | 274 | if (strlen(val) > 1024) { |
b5f3abf9 | 275 | pr_err("%s: string parameter too long\n", kp->name); |
1da177e4 LT |
276 | return -ENOSPC; |
277 | } | |
278 | ||
a1054322 RR |
279 | maybe_kfree_parameter(*(char **)kp->arg); |
280 | ||
281 | /* This is a hack. We can't kmalloc in early boot, and we | |
e180a6b7 RR |
282 | * don't need to; this mangled commandline is preserved. */ |
283 | if (slab_is_available()) { | |
a1054322 | 284 | *(char **)kp->arg = kmalloc_parameter(strlen(val)+1); |
d553ad86 | 285 | if (!*(char **)kp->arg) |
e180a6b7 | 286 | return -ENOMEM; |
a1054322 | 287 | strcpy(*(char **)kp->arg, val); |
e180a6b7 RR |
288 | } else |
289 | *(const char **)kp->arg = val; | |
290 | ||
1da177e4 LT |
291 | return 0; |
292 | } | |
a14fe249 | 293 | EXPORT_SYMBOL(param_set_charp); |
1da177e4 | 294 | |
9bbb9e5a | 295 | int param_get_charp(char *buffer, const struct kernel_param *kp) |
1da177e4 | 296 | { |
f4940ab7 | 297 | return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg)); |
1da177e4 | 298 | } |
a14fe249 | 299 | EXPORT_SYMBOL(param_get_charp); |
1da177e4 | 300 | |
a1054322 RR |
301 | static void param_free_charp(void *arg) |
302 | { | |
303 | maybe_kfree_parameter(*((char **)arg)); | |
304 | } | |
305 | ||
9bbb9e5a RR |
306 | struct kernel_param_ops param_ops_charp = { |
307 | .set = param_set_charp, | |
308 | .get = param_get_charp, | |
a1054322 | 309 | .free = param_free_charp, |
9bbb9e5a RR |
310 | }; |
311 | EXPORT_SYMBOL(param_ops_charp); | |
312 | ||
fddd5201 | 313 | /* Actually could be a bool or an int, for historical reasons. */ |
9bbb9e5a | 314 | int param_set_bool(const char *val, const struct kernel_param *kp) |
1da177e4 LT |
315 | { |
316 | /* No equals means "set"... */ | |
317 | if (!val) val = "1"; | |
318 | ||
319 | /* One of =[yYnN01] */ | |
8b825281 | 320 | return strtobool(val, kp->arg); |
1da177e4 | 321 | } |
a14fe249 | 322 | EXPORT_SYMBOL(param_set_bool); |
1da177e4 | 323 | |
9bbb9e5a | 324 | int param_get_bool(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
325 | { |
326 | /* Y and N chosen as being relatively non-coder friendly */ | |
8b825281 | 327 | return sprintf(buffer, "%c", *(bool *)kp->arg ? 'Y' : 'N'); |
1da177e4 | 328 | } |
a14fe249 | 329 | EXPORT_SYMBOL(param_get_bool); |
1da177e4 | 330 | |
9bbb9e5a | 331 | struct kernel_param_ops param_ops_bool = { |
6a4c2643 | 332 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
9bbb9e5a RR |
333 | .set = param_set_bool, |
334 | .get = param_get_bool, | |
335 | }; | |
336 | EXPORT_SYMBOL(param_ops_bool); | |
337 | ||
fddd5201 | 338 | /* This one must be bool. */ |
9bbb9e5a | 339 | int param_set_invbool(const char *val, const struct kernel_param *kp) |
1da177e4 | 340 | { |
fddd5201 RR |
341 | int ret; |
342 | bool boolval; | |
22e48eaf | 343 | struct kernel_param dummy; |
1da177e4 | 344 | |
22e48eaf | 345 | dummy.arg = &boolval; |
1da177e4 LT |
346 | ret = param_set_bool(val, &dummy); |
347 | if (ret == 0) | |
9a71af2c | 348 | *(bool *)kp->arg = !boolval; |
1da177e4 LT |
349 | return ret; |
350 | } | |
a14fe249 | 351 | EXPORT_SYMBOL(param_set_invbool); |
1da177e4 | 352 | |
9bbb9e5a | 353 | int param_get_invbool(char *buffer, const struct kernel_param *kp) |
1da177e4 | 354 | { |
9a71af2c | 355 | return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y'); |
1da177e4 | 356 | } |
a14fe249 | 357 | EXPORT_SYMBOL(param_get_invbool); |
1da177e4 | 358 | |
9bbb9e5a RR |
359 | struct kernel_param_ops param_ops_invbool = { |
360 | .set = param_set_invbool, | |
361 | .get = param_get_invbool, | |
362 | }; | |
363 | EXPORT_SYMBOL(param_ops_invbool); | |
364 | ||
69116f27 RR |
365 | int param_set_bint(const char *val, const struct kernel_param *kp) |
366 | { | |
367 | struct kernel_param boolkp; | |
368 | bool v; | |
369 | int ret; | |
370 | ||
371 | /* Match bool exactly, by re-using it. */ | |
372 | boolkp = *kp; | |
373 | boolkp.arg = &v; | |
69116f27 RR |
374 | |
375 | ret = param_set_bool(val, &boolkp); | |
376 | if (ret == 0) | |
377 | *(int *)kp->arg = v; | |
378 | return ret; | |
379 | } | |
380 | EXPORT_SYMBOL(param_set_bint); | |
381 | ||
382 | struct kernel_param_ops param_ops_bint = { | |
6a4c2643 | 383 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
69116f27 RR |
384 | .set = param_set_bint, |
385 | .get = param_get_int, | |
386 | }; | |
387 | EXPORT_SYMBOL(param_ops_bint); | |
388 | ||
9730b5b0 | 389 | /* We break the rule and mangle the string. */ |
9871728b AB |
390 | static int param_array(const char *name, |
391 | const char *val, | |
392 | unsigned int min, unsigned int max, | |
393 | void *elem, int elemsize, | |
9bbb9e5a | 394 | int (*set)(const char *, const struct kernel_param *kp), |
026cee00 | 395 | s16 level, |
eb38a996 | 396 | unsigned int *num) |
1da177e4 LT |
397 | { |
398 | int ret; | |
399 | struct kernel_param kp; | |
400 | char save; | |
401 | ||
402 | /* Get the name right for errors. */ | |
403 | kp.name = name; | |
404 | kp.arg = elem; | |
026cee00 | 405 | kp.level = level; |
1da177e4 | 406 | |
1da177e4 LT |
407 | *num = 0; |
408 | /* We expect a comma-separated list of values. */ | |
409 | do { | |
410 | int len; | |
411 | ||
412 | if (*num == max) { | |
b5f3abf9 | 413 | pr_err("%s: can only take %i arguments\n", name, max); |
1da177e4 LT |
414 | return -EINVAL; |
415 | } | |
416 | len = strcspn(val, ","); | |
417 | ||
418 | /* nul-terminate and parse */ | |
419 | save = val[len]; | |
420 | ((char *)val)[len] = '\0'; | |
907b29eb | 421 | BUG_ON(!mutex_is_locked(¶m_lock)); |
1da177e4 LT |
422 | ret = set(val, &kp); |
423 | ||
424 | if (ret != 0) | |
425 | return ret; | |
426 | kp.arg += elemsize; | |
427 | val += len+1; | |
428 | (*num)++; | |
429 | } while (save == ','); | |
430 | ||
431 | if (*num < min) { | |
b5f3abf9 | 432 | pr_err("%s: needs at least %i arguments\n", name, min); |
1da177e4 LT |
433 | return -EINVAL; |
434 | } | |
435 | return 0; | |
436 | } | |
437 | ||
9bbb9e5a | 438 | static int param_array_set(const char *val, const struct kernel_param *kp) |
1da177e4 | 439 | { |
22e48eaf | 440 | const struct kparam_array *arr = kp->arr; |
31143a12 | 441 | unsigned int temp_num; |
1da177e4 LT |
442 | |
443 | return param_array(kp->name, val, 1, arr->max, arr->elem, | |
026cee00 | 444 | arr->elemsize, arr->ops->set, kp->level, |
3c7d76e3 | 445 | arr->num ?: &temp_num); |
1da177e4 LT |
446 | } |
447 | ||
9bbb9e5a | 448 | static int param_array_get(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
449 | { |
450 | int i, off, ret; | |
22e48eaf | 451 | const struct kparam_array *arr = kp->arr; |
1da177e4 LT |
452 | struct kernel_param p; |
453 | ||
454 | p = *kp; | |
455 | for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) { | |
456 | if (i) | |
457 | buffer[off++] = ','; | |
458 | p.arg = arr->elem + arr->elemsize * i; | |
907b29eb | 459 | BUG_ON(!mutex_is_locked(¶m_lock)); |
9bbb9e5a | 460 | ret = arr->ops->get(buffer + off, &p); |
1da177e4 LT |
461 | if (ret < 0) |
462 | return ret; | |
463 | off += ret; | |
464 | } | |
465 | buffer[off] = '\0'; | |
466 | return off; | |
467 | } | |
468 | ||
e6df34a4 RR |
469 | static void param_array_free(void *arg) |
470 | { | |
471 | unsigned int i; | |
472 | const struct kparam_array *arr = arg; | |
473 | ||
474 | if (arr->ops->free) | |
475 | for (i = 0; i < (arr->num ? *arr->num : arr->max); i++) | |
476 | arr->ops->free(arr->elem + arr->elemsize * i); | |
477 | } | |
478 | ||
9bbb9e5a RR |
479 | struct kernel_param_ops param_array_ops = { |
480 | .set = param_array_set, | |
481 | .get = param_array_get, | |
e6df34a4 | 482 | .free = param_array_free, |
9bbb9e5a RR |
483 | }; |
484 | EXPORT_SYMBOL(param_array_ops); | |
485 | ||
486 | int param_set_copystring(const char *val, const struct kernel_param *kp) | |
1da177e4 | 487 | { |
22e48eaf | 488 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
489 | |
490 | if (strlen(val)+1 > kps->maxlen) { | |
b5f3abf9 | 491 | pr_err("%s: string doesn't fit in %u chars.\n", |
1da177e4 LT |
492 | kp->name, kps->maxlen-1); |
493 | return -ENOSPC; | |
494 | } | |
495 | strcpy(kps->string, val); | |
496 | return 0; | |
497 | } | |
a14fe249 | 498 | EXPORT_SYMBOL(param_set_copystring); |
1da177e4 | 499 | |
9bbb9e5a | 500 | int param_get_string(char *buffer, const struct kernel_param *kp) |
1da177e4 | 501 | { |
22e48eaf | 502 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
503 | return strlcpy(buffer, kps->string, kps->maxlen); |
504 | } | |
a14fe249 | 505 | EXPORT_SYMBOL(param_get_string); |
1da177e4 | 506 | |
9bbb9e5a RR |
507 | struct kernel_param_ops param_ops_string = { |
508 | .set = param_set_copystring, | |
509 | .get = param_get_string, | |
510 | }; | |
511 | EXPORT_SYMBOL(param_ops_string); | |
512 | ||
1da177e4 | 513 | /* sysfs output in /sys/modules/XYZ/parameters/ */ |
350f8258 EY |
514 | #define to_module_attr(n) container_of(n, struct module_attribute, attr) |
515 | #define to_module_kobject(n) container_of(n, struct module_kobject, kobj) | |
1da177e4 | 516 | |
1da177e4 LT |
517 | struct param_attribute |
518 | { | |
519 | struct module_attribute mattr; | |
9bbb9e5a | 520 | const struct kernel_param *param; |
1da177e4 LT |
521 | }; |
522 | ||
523 | struct module_param_attrs | |
524 | { | |
9b473de8 | 525 | unsigned int num; |
1da177e4 LT |
526 | struct attribute_group grp; |
527 | struct param_attribute attrs[0]; | |
528 | }; | |
529 | ||
ef665c1a | 530 | #ifdef CONFIG_SYSFS |
350f8258 | 531 | #define to_param_attr(n) container_of(n, struct param_attribute, mattr) |
1da177e4 LT |
532 | |
533 | static ssize_t param_attr_show(struct module_attribute *mattr, | |
4befb026 | 534 | struct module_kobject *mk, char *buf) |
1da177e4 LT |
535 | { |
536 | int count; | |
537 | struct param_attribute *attribute = to_param_attr(mattr); | |
538 | ||
9bbb9e5a | 539 | if (!attribute->param->ops->get) |
1da177e4 LT |
540 | return -EPERM; |
541 | ||
907b29eb | 542 | mutex_lock(¶m_lock); |
9bbb9e5a | 543 | count = attribute->param->ops->get(buf, attribute->param); |
907b29eb | 544 | mutex_unlock(¶m_lock); |
1da177e4 LT |
545 | if (count > 0) { |
546 | strcat(buf, "\n"); | |
547 | ++count; | |
548 | } | |
549 | return count; | |
550 | } | |
551 | ||
552 | /* sysfs always hands a nul-terminated string in buf. We rely on that. */ | |
553 | static ssize_t param_attr_store(struct module_attribute *mattr, | |
4befb026 | 554 | struct module_kobject *km, |
1da177e4 LT |
555 | const char *buf, size_t len) |
556 | { | |
557 | int err; | |
558 | struct param_attribute *attribute = to_param_attr(mattr); | |
559 | ||
9bbb9e5a | 560 | if (!attribute->param->ops->set) |
1da177e4 LT |
561 | return -EPERM; |
562 | ||
907b29eb | 563 | mutex_lock(¶m_lock); |
7a486d37 | 564 | param_check_unsafe(attribute->param); |
9bbb9e5a | 565 | err = attribute->param->ops->set(buf, attribute->param); |
907b29eb | 566 | mutex_unlock(¶m_lock); |
1da177e4 LT |
567 | if (!err) |
568 | return len; | |
569 | return err; | |
570 | } | |
ef665c1a | 571 | #endif |
1da177e4 LT |
572 | |
573 | #ifdef CONFIG_MODULES | |
574 | #define __modinit | |
575 | #else | |
576 | #define __modinit __init | |
577 | #endif | |
578 | ||
ef665c1a | 579 | #ifdef CONFIG_SYSFS |
907b29eb RR |
580 | void __kernel_param_lock(void) |
581 | { | |
582 | mutex_lock(¶m_lock); | |
583 | } | |
584 | EXPORT_SYMBOL(__kernel_param_lock); | |
585 | ||
586 | void __kernel_param_unlock(void) | |
587 | { | |
588 | mutex_unlock(¶m_lock); | |
589 | } | |
590 | EXPORT_SYMBOL(__kernel_param_unlock); | |
591 | ||
1da177e4 | 592 | /* |
9b473de8 RR |
593 | * add_sysfs_param - add a parameter to sysfs |
594 | * @mk: struct module_kobject | |
595 | * @kparam: the actual parameter definition to add to sysfs | |
596 | * @name: name of parameter | |
1da177e4 | 597 | * |
9b473de8 RR |
598 | * Create a kobject if for a (per-module) parameter if mp NULL, and |
599 | * create file in sysfs. Returns an error on out of memory. Always cleans up | |
600 | * if there's an error. | |
1da177e4 | 601 | */ |
9b473de8 | 602 | static __modinit int add_sysfs_param(struct module_kobject *mk, |
9bbb9e5a | 603 | const struct kernel_param *kp, |
9b473de8 | 604 | const char *name) |
1da177e4 | 605 | { |
9b473de8 RR |
606 | struct module_param_attrs *new; |
607 | struct attribute **attrs; | |
608 | int err, num; | |
609 | ||
610 | /* We don't bother calling this with invisible parameters. */ | |
611 | BUG_ON(!kp->perm); | |
612 | ||
613 | if (!mk->mp) { | |
614 | num = 0; | |
615 | attrs = NULL; | |
616 | } else { | |
617 | num = mk->mp->num; | |
618 | attrs = mk->mp->grp.attrs; | |
1da177e4 LT |
619 | } |
620 | ||
9b473de8 RR |
621 | /* Enlarge. */ |
622 | new = krealloc(mk->mp, | |
623 | sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1), | |
624 | GFP_KERNEL); | |
625 | if (!new) { | |
63662139 | 626 | kfree(attrs); |
9b473de8 RR |
627 | err = -ENOMEM; |
628 | goto fail; | |
629 | } | |
63662139 DW |
630 | /* Despite looking like the typical realloc() bug, this is safe. |
631 | * We *want* the old 'attrs' to be freed either way, and we'll store | |
632 | * the new one in the success case. */ | |
9b473de8 RR |
633 | attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL); |
634 | if (!attrs) { | |
635 | err = -ENOMEM; | |
636 | goto fail_free_new; | |
637 | } | |
1da177e4 | 638 | |
9b473de8 RR |
639 | /* Sysfs wants everything zeroed. */ |
640 | memset(new, 0, sizeof(*new)); | |
641 | memset(&new->attrs[num], 0, sizeof(new->attrs[num])); | |
642 | memset(&attrs[num], 0, sizeof(attrs[num])); | |
643 | new->grp.name = "parameters"; | |
644 | new->grp.attrs = attrs; | |
645 | ||
646 | /* Tack new one on the end. */ | |
a07e4156 | 647 | sysfs_attr_init(&new->attrs[num].mattr.attr); |
9b473de8 RR |
648 | new->attrs[num].param = kp; |
649 | new->attrs[num].mattr.show = param_attr_show; | |
650 | new->attrs[num].mattr.store = param_attr_store; | |
651 | new->attrs[num].mattr.attr.name = (char *)name; | |
652 | new->attrs[num].mattr.attr.mode = kp->perm; | |
653 | new->num = num+1; | |
654 | ||
655 | /* Fix up all the pointers, since krealloc can move us */ | |
656 | for (num = 0; num < new->num; num++) | |
657 | new->grp.attrs[num] = &new->attrs[num].mattr.attr; | |
658 | new->grp.attrs[num] = NULL; | |
659 | ||
660 | mk->mp = new; | |
661 | return 0; | |
1da177e4 | 662 | |
9b473de8 RR |
663 | fail_free_new: |
664 | kfree(new); | |
665 | fail: | |
666 | mk->mp = NULL; | |
667 | return err; | |
668 | } | |
1da177e4 | 669 | |
d2441183 | 670 | #ifdef CONFIG_MODULES |
9b473de8 RR |
671 | static void free_module_param_attrs(struct module_kobject *mk) |
672 | { | |
673 | kfree(mk->mp->grp.attrs); | |
674 | kfree(mk->mp); | |
675 | mk->mp = NULL; | |
1da177e4 LT |
676 | } |
677 | ||
1da177e4 LT |
678 | /* |
679 | * module_param_sysfs_setup - setup sysfs support for one module | |
680 | * @mod: module | |
681 | * @kparam: module parameters (array) | |
682 | * @num_params: number of module parameters | |
683 | * | |
9b473de8 RR |
684 | * Adds sysfs entries for module parameters under |
685 | * /sys/module/[mod->name]/parameters/ | |
1da177e4 LT |
686 | */ |
687 | int module_param_sysfs_setup(struct module *mod, | |
9bbb9e5a | 688 | const struct kernel_param *kparam, |
1da177e4 LT |
689 | unsigned int num_params) |
690 | { | |
9b473de8 RR |
691 | int i, err; |
692 | bool params = false; | |
693 | ||
694 | for (i = 0; i < num_params; i++) { | |
695 | if (kparam[i].perm == 0) | |
696 | continue; | |
697 | err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name); | |
698 | if (err) | |
699 | return err; | |
700 | params = true; | |
701 | } | |
1da177e4 | 702 | |
9b473de8 RR |
703 | if (!params) |
704 | return 0; | |
1da177e4 | 705 | |
9b473de8 RR |
706 | /* Create the param group. */ |
707 | err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
708 | if (err) | |
709 | free_module_param_attrs(&mod->mkobj); | |
710 | return err; | |
1da177e4 LT |
711 | } |
712 | ||
713 | /* | |
714 | * module_param_sysfs_remove - remove sysfs support for one module | |
715 | * @mod: module | |
716 | * | |
717 | * Remove sysfs entries for module parameters and the corresponding | |
718 | * kobject. | |
719 | */ | |
720 | void module_param_sysfs_remove(struct module *mod) | |
721 | { | |
9b473de8 RR |
722 | if (mod->mkobj.mp) { |
723 | sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
1da177e4 LT |
724 | /* We are positive that no one is using any param |
725 | * attrs at this point. Deallocate immediately. */ | |
9b473de8 | 726 | free_module_param_attrs(&mod->mkobj); |
1da177e4 LT |
727 | } |
728 | } | |
729 | #endif | |
730 | ||
e180a6b7 RR |
731 | void destroy_params(const struct kernel_param *params, unsigned num) |
732 | { | |
e6df34a4 RR |
733 | unsigned int i; |
734 | ||
735 | for (i = 0; i < num; i++) | |
736 | if (params[i].ops->free) | |
737 | params[i].ops->free(params[i].arg); | |
e180a6b7 RR |
738 | } |
739 | ||
e94965ed | 740 | static struct module_kobject * __init locate_module_kobject(const char *name) |
1da177e4 LT |
741 | { |
742 | struct module_kobject *mk; | |
9b473de8 RR |
743 | struct kobject *kobj; |
744 | int err; | |
1da177e4 | 745 | |
9b473de8 RR |
746 | kobj = kset_find_obj(module_kset, name); |
747 | if (kobj) { | |
9b473de8 | 748 | mk = to_module_kobject(kobj); |
9b473de8 RR |
749 | } else { |
750 | mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL); | |
751 | BUG_ON(!mk); | |
752 | ||
753 | mk->mod = THIS_MODULE; | |
754 | mk->kobj.kset = module_kset; | |
755 | err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL, | |
756 | "%s", name); | |
88bfa324 KS |
757 | #ifdef CONFIG_MODULES |
758 | if (!err) | |
759 | err = sysfs_create_file(&mk->kobj, &module_uevent.attr); | |
760 | #endif | |
9b473de8 RR |
761 | if (err) { |
762 | kobject_put(&mk->kobj); | |
b5f3abf9 | 763 | pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n", |
e94965ed | 764 | name, err); |
e94965ed | 765 | return NULL; |
9b473de8 | 766 | } |
e94965ed DT |
767 | |
768 | /* So that we hold reference in both cases. */ | |
9b473de8 | 769 | kobject_get(&mk->kobj); |
74c5b597 | 770 | } |
9b473de8 | 771 | |
e94965ed DT |
772 | return mk; |
773 | } | |
774 | ||
775 | static void __init kernel_add_sysfs_param(const char *name, | |
63a12d9d | 776 | const struct kernel_param *kparam, |
e94965ed DT |
777 | unsigned int name_skip) |
778 | { | |
779 | struct module_kobject *mk; | |
780 | int err; | |
781 | ||
782 | mk = locate_module_kobject(name); | |
783 | if (!mk) | |
784 | return; | |
785 | ||
786 | /* We need to remove old parameters before adding more. */ | |
787 | if (mk->mp) | |
788 | sysfs_remove_group(&mk->kobj, &mk->mp->grp); | |
789 | ||
9b473de8 RR |
790 | /* These should not fail at boot. */ |
791 | err = add_sysfs_param(mk, kparam, kparam->name + name_skip); | |
792 | BUG_ON(err); | |
793 | err = sysfs_create_group(&mk->kobj, &mk->mp->grp); | |
794 | BUG_ON(err); | |
f30c53a8 | 795 | kobject_uevent(&mk->kobj, KOBJ_ADD); |
9b473de8 | 796 | kobject_put(&mk->kobj); |
1da177e4 LT |
797 | } |
798 | ||
799 | /* | |
b634d130 | 800 | * param_sysfs_builtin - add sysfs parameters for built-in modules |
1da177e4 LT |
801 | * |
802 | * Add module_parameters to sysfs for "modules" built into the kernel. | |
803 | * | |
804 | * The "module" name (KBUILD_MODNAME) is stored before a dot, the | |
805 | * "parameter" name is stored behind a dot in kernel_param->name. So, | |
806 | * extract the "module" name for all built-in kernel_param-eters, | |
9b473de8 | 807 | * and for all who have the same, call kernel_add_sysfs_param. |
1da177e4 LT |
808 | */ |
809 | static void __init param_sysfs_builtin(void) | |
810 | { | |
63a12d9d | 811 | const struct kernel_param *kp; |
9b473de8 RR |
812 | unsigned int name_len; |
813 | char modname[MODULE_NAME_LEN]; | |
1da177e4 | 814 | |
9b473de8 | 815 | for (kp = __start___param; kp < __stop___param; kp++) { |
1da177e4 LT |
816 | char *dot; |
817 | ||
9b473de8 RR |
818 | if (kp->perm == 0) |
819 | continue; | |
1da177e4 | 820 | |
730b69d2 | 821 | dot = strchr(kp->name, '.'); |
1da177e4 | 822 | if (!dot) { |
67e67cea RR |
823 | /* This happens for core_param() */ |
824 | strcpy(modname, "kernel"); | |
825 | name_len = 0; | |
826 | } else { | |
827 | name_len = dot - kp->name + 1; | |
828 | strlcpy(modname, kp->name, name_len); | |
1da177e4 | 829 | } |
67e67cea | 830 | kernel_add_sysfs_param(modname, kp, name_len); |
1da177e4 | 831 | } |
1da177e4 LT |
832 | } |
833 | ||
e94965ed | 834 | ssize_t __modver_version_show(struct module_attribute *mattr, |
4befb026 | 835 | struct module_kobject *mk, char *buf) |
e94965ed DT |
836 | { |
837 | struct module_version_attribute *vattr = | |
838 | container_of(mattr, struct module_version_attribute, mattr); | |
839 | ||
f4940ab7 | 840 | return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version); |
e94965ed DT |
841 | } |
842 | ||
b4bc8428 DT |
843 | extern const struct module_version_attribute *__start___modver[]; |
844 | extern const struct module_version_attribute *__stop___modver[]; | |
e94965ed DT |
845 | |
846 | static void __init version_sysfs_builtin(void) | |
847 | { | |
b4bc8428 | 848 | const struct module_version_attribute **p; |
e94965ed DT |
849 | struct module_kobject *mk; |
850 | int err; | |
851 | ||
b4bc8428 DT |
852 | for (p = __start___modver; p < __stop___modver; p++) { |
853 | const struct module_version_attribute *vattr = *p; | |
854 | ||
e94965ed DT |
855 | mk = locate_module_kobject(vattr->module_name); |
856 | if (mk) { | |
857 | err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr); | |
858 | kobject_uevent(&mk->kobj, KOBJ_ADD); | |
859 | kobject_put(&mk->kobj); | |
860 | } | |
861 | } | |
862 | } | |
1da177e4 LT |
863 | |
864 | /* module-related sysfs stuff */ | |
1da177e4 | 865 | |
1da177e4 LT |
866 | static ssize_t module_attr_show(struct kobject *kobj, |
867 | struct attribute *attr, | |
868 | char *buf) | |
869 | { | |
870 | struct module_attribute *attribute; | |
871 | struct module_kobject *mk; | |
872 | int ret; | |
873 | ||
874 | attribute = to_module_attr(attr); | |
875 | mk = to_module_kobject(kobj); | |
876 | ||
877 | if (!attribute->show) | |
70f2817a | 878 | return -EIO; |
1da177e4 | 879 | |
4befb026 | 880 | ret = attribute->show(attribute, mk, buf); |
1da177e4 | 881 | |
1da177e4 LT |
882 | return ret; |
883 | } | |
884 | ||
885 | static ssize_t module_attr_store(struct kobject *kobj, | |
886 | struct attribute *attr, | |
887 | const char *buf, size_t len) | |
888 | { | |
889 | struct module_attribute *attribute; | |
890 | struct module_kobject *mk; | |
891 | int ret; | |
892 | ||
893 | attribute = to_module_attr(attr); | |
894 | mk = to_module_kobject(kobj); | |
895 | ||
896 | if (!attribute->store) | |
70f2817a | 897 | return -EIO; |
1da177e4 | 898 | |
4befb026 | 899 | ret = attribute->store(attribute, mk, buf, len); |
1da177e4 | 900 | |
1da177e4 LT |
901 | return ret; |
902 | } | |
903 | ||
52cf25d0 | 904 | static const struct sysfs_ops module_sysfs_ops = { |
1da177e4 LT |
905 | .show = module_attr_show, |
906 | .store = module_attr_store, | |
907 | }; | |
908 | ||
270a6c4c KS |
909 | static int uevent_filter(struct kset *kset, struct kobject *kobj) |
910 | { | |
911 | struct kobj_type *ktype = get_ktype(kobj); | |
912 | ||
913 | if (ktype == &module_ktype) | |
914 | return 1; | |
915 | return 0; | |
916 | } | |
917 | ||
9cd43611 | 918 | static const struct kset_uevent_ops module_uevent_ops = { |
270a6c4c KS |
919 | .filter = uevent_filter, |
920 | }; | |
921 | ||
7405c1e1 | 922 | struct kset *module_kset; |
823bccfc | 923 | int module_sysfs_initialized; |
1da177e4 | 924 | |
942e4431 LZ |
925 | static void module_kobj_release(struct kobject *kobj) |
926 | { | |
927 | struct module_kobject *mk = to_module_kobject(kobj); | |
928 | complete(mk->kobj_completion); | |
929 | } | |
930 | ||
7405c1e1 | 931 | struct kobj_type module_ktype = { |
942e4431 | 932 | .release = module_kobj_release, |
1da177e4 LT |
933 | .sysfs_ops = &module_sysfs_ops, |
934 | }; | |
935 | ||
1da177e4 LT |
936 | /* |
937 | * param_sysfs_init - wrapper for built-in params support | |
938 | */ | |
939 | static int __init param_sysfs_init(void) | |
940 | { | |
7405c1e1 GKH |
941 | module_kset = kset_create_and_add("module", &module_uevent_ops, NULL); |
942 | if (!module_kset) { | |
943 | printk(KERN_WARNING "%s (%d): error creating kset\n", | |
944 | __FILE__, __LINE__); | |
945 | return -ENOMEM; | |
d8c7649e | 946 | } |
823bccfc | 947 | module_sysfs_initialized = 1; |
1da177e4 | 948 | |
e94965ed | 949 | version_sysfs_builtin(); |
1da177e4 LT |
950 | param_sysfs_builtin(); |
951 | ||
952 | return 0; | |
953 | } | |
d10be6d1 | 954 | subsys_initcall(param_sysfs_init); |
1da177e4 | 955 | |
7405c1e1 | 956 | #endif /* CONFIG_SYSFS */ |