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 | } | |
1da177e4 | 176 | } |
b9cc4489 RR |
177 | if (quoted && args[i-1] == '"') |
178 | args[i-1] = '\0'; | |
1da177e4 LT |
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 | } \ |
9c27847d | 254 | const struct kernel_param_ops param_ops_##name = { \ |
9bbb9e5a RR |
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 | ||
9c27847d | 306 | const struct kernel_param_ops param_ops_charp = { |
9bbb9e5a RR |
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 | |
9c27847d | 331 | const 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 | ||
d19f05d8 LR |
338 | int param_set_bool_enable_only(const char *val, const struct kernel_param *kp) |
339 | { | |
340 | int err = 0; | |
341 | bool new_value; | |
342 | bool orig_value = *(bool *)kp->arg; | |
343 | struct kernel_param dummy_kp = *kp; | |
344 | ||
345 | dummy_kp.arg = &new_value; | |
346 | ||
347 | err = param_set_bool(val, &dummy_kp); | |
348 | if (err) | |
349 | return err; | |
350 | ||
351 | /* Don't let them unset it once it's set! */ | |
352 | if (!new_value && orig_value) | |
353 | return -EROFS; | |
354 | ||
355 | if (new_value) | |
356 | err = param_set_bool(val, kp); | |
357 | ||
358 | return err; | |
359 | } | |
360 | EXPORT_SYMBOL_GPL(param_set_bool_enable_only); | |
361 | ||
362 | const struct kernel_param_ops param_ops_bool_enable_only = { | |
363 | .flags = KERNEL_PARAM_OPS_FL_NOARG, | |
364 | .set = param_set_bool_enable_only, | |
365 | .get = param_get_bool, | |
366 | }; | |
367 | ||
fddd5201 | 368 | /* This one must be bool. */ |
9bbb9e5a | 369 | int param_set_invbool(const char *val, const struct kernel_param *kp) |
1da177e4 | 370 | { |
fddd5201 RR |
371 | int ret; |
372 | bool boolval; | |
22e48eaf | 373 | struct kernel_param dummy; |
1da177e4 | 374 | |
22e48eaf | 375 | dummy.arg = &boolval; |
1da177e4 LT |
376 | ret = param_set_bool(val, &dummy); |
377 | if (ret == 0) | |
9a71af2c | 378 | *(bool *)kp->arg = !boolval; |
1da177e4 LT |
379 | return ret; |
380 | } | |
a14fe249 | 381 | EXPORT_SYMBOL(param_set_invbool); |
1da177e4 | 382 | |
9bbb9e5a | 383 | int param_get_invbool(char *buffer, const struct kernel_param *kp) |
1da177e4 | 384 | { |
9a71af2c | 385 | return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y'); |
1da177e4 | 386 | } |
a14fe249 | 387 | EXPORT_SYMBOL(param_get_invbool); |
1da177e4 | 388 | |
9c27847d | 389 | const struct kernel_param_ops param_ops_invbool = { |
9bbb9e5a RR |
390 | .set = param_set_invbool, |
391 | .get = param_get_invbool, | |
392 | }; | |
393 | EXPORT_SYMBOL(param_ops_invbool); | |
394 | ||
69116f27 RR |
395 | int param_set_bint(const char *val, const struct kernel_param *kp) |
396 | { | |
397 | struct kernel_param boolkp; | |
398 | bool v; | |
399 | int ret; | |
400 | ||
401 | /* Match bool exactly, by re-using it. */ | |
402 | boolkp = *kp; | |
403 | boolkp.arg = &v; | |
69116f27 RR |
404 | |
405 | ret = param_set_bool(val, &boolkp); | |
406 | if (ret == 0) | |
407 | *(int *)kp->arg = v; | |
408 | return ret; | |
409 | } | |
410 | EXPORT_SYMBOL(param_set_bint); | |
411 | ||
9c27847d | 412 | const struct kernel_param_ops param_ops_bint = { |
6a4c2643 | 413 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
69116f27 RR |
414 | .set = param_set_bint, |
415 | .get = param_get_int, | |
416 | }; | |
417 | EXPORT_SYMBOL(param_ops_bint); | |
418 | ||
9730b5b0 | 419 | /* We break the rule and mangle the string. */ |
9871728b AB |
420 | static int param_array(const char *name, |
421 | const char *val, | |
422 | unsigned int min, unsigned int max, | |
423 | void *elem, int elemsize, | |
9bbb9e5a | 424 | int (*set)(const char *, const struct kernel_param *kp), |
026cee00 | 425 | s16 level, |
eb38a996 | 426 | unsigned int *num) |
1da177e4 LT |
427 | { |
428 | int ret; | |
429 | struct kernel_param kp; | |
430 | char save; | |
431 | ||
432 | /* Get the name right for errors. */ | |
433 | kp.name = name; | |
434 | kp.arg = elem; | |
026cee00 | 435 | kp.level = level; |
1da177e4 | 436 | |
1da177e4 LT |
437 | *num = 0; |
438 | /* We expect a comma-separated list of values. */ | |
439 | do { | |
440 | int len; | |
441 | ||
442 | if (*num == max) { | |
b5f3abf9 | 443 | pr_err("%s: can only take %i arguments\n", name, max); |
1da177e4 LT |
444 | return -EINVAL; |
445 | } | |
446 | len = strcspn(val, ","); | |
447 | ||
448 | /* nul-terminate and parse */ | |
449 | save = val[len]; | |
450 | ((char *)val)[len] = '\0'; | |
907b29eb | 451 | BUG_ON(!mutex_is_locked(¶m_lock)); |
1da177e4 LT |
452 | ret = set(val, &kp); |
453 | ||
454 | if (ret != 0) | |
455 | return ret; | |
456 | kp.arg += elemsize; | |
457 | val += len+1; | |
458 | (*num)++; | |
459 | } while (save == ','); | |
460 | ||
461 | if (*num < min) { | |
b5f3abf9 | 462 | pr_err("%s: needs at least %i arguments\n", name, min); |
1da177e4 LT |
463 | return -EINVAL; |
464 | } | |
465 | return 0; | |
466 | } | |
467 | ||
9bbb9e5a | 468 | static int param_array_set(const char *val, const struct kernel_param *kp) |
1da177e4 | 469 | { |
22e48eaf | 470 | const struct kparam_array *arr = kp->arr; |
31143a12 | 471 | unsigned int temp_num; |
1da177e4 LT |
472 | |
473 | return param_array(kp->name, val, 1, arr->max, arr->elem, | |
026cee00 | 474 | arr->elemsize, arr->ops->set, kp->level, |
3c7d76e3 | 475 | arr->num ?: &temp_num); |
1da177e4 LT |
476 | } |
477 | ||
9bbb9e5a | 478 | static int param_array_get(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
479 | { |
480 | int i, off, ret; | |
22e48eaf | 481 | const struct kparam_array *arr = kp->arr; |
1da177e4 LT |
482 | struct kernel_param p; |
483 | ||
484 | p = *kp; | |
485 | for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) { | |
486 | if (i) | |
487 | buffer[off++] = ','; | |
488 | p.arg = arr->elem + arr->elemsize * i; | |
907b29eb | 489 | BUG_ON(!mutex_is_locked(¶m_lock)); |
9bbb9e5a | 490 | ret = arr->ops->get(buffer + off, &p); |
1da177e4 LT |
491 | if (ret < 0) |
492 | return ret; | |
493 | off += ret; | |
494 | } | |
495 | buffer[off] = '\0'; | |
496 | return off; | |
497 | } | |
498 | ||
e6df34a4 RR |
499 | static void param_array_free(void *arg) |
500 | { | |
501 | unsigned int i; | |
502 | const struct kparam_array *arr = arg; | |
503 | ||
504 | if (arr->ops->free) | |
505 | for (i = 0; i < (arr->num ? *arr->num : arr->max); i++) | |
506 | arr->ops->free(arr->elem + arr->elemsize * i); | |
507 | } | |
508 | ||
9c27847d | 509 | const struct kernel_param_ops param_array_ops = { |
9bbb9e5a RR |
510 | .set = param_array_set, |
511 | .get = param_array_get, | |
e6df34a4 | 512 | .free = param_array_free, |
9bbb9e5a RR |
513 | }; |
514 | EXPORT_SYMBOL(param_array_ops); | |
515 | ||
516 | int param_set_copystring(const char *val, const struct kernel_param *kp) | |
1da177e4 | 517 | { |
22e48eaf | 518 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
519 | |
520 | if (strlen(val)+1 > kps->maxlen) { | |
b5f3abf9 | 521 | pr_err("%s: string doesn't fit in %u chars.\n", |
1da177e4 LT |
522 | kp->name, kps->maxlen-1); |
523 | return -ENOSPC; | |
524 | } | |
525 | strcpy(kps->string, val); | |
526 | return 0; | |
527 | } | |
a14fe249 | 528 | EXPORT_SYMBOL(param_set_copystring); |
1da177e4 | 529 | |
9bbb9e5a | 530 | int param_get_string(char *buffer, const struct kernel_param *kp) |
1da177e4 | 531 | { |
22e48eaf | 532 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
533 | return strlcpy(buffer, kps->string, kps->maxlen); |
534 | } | |
a14fe249 | 535 | EXPORT_SYMBOL(param_get_string); |
1da177e4 | 536 | |
9c27847d | 537 | const struct kernel_param_ops param_ops_string = { |
9bbb9e5a RR |
538 | .set = param_set_copystring, |
539 | .get = param_get_string, | |
540 | }; | |
541 | EXPORT_SYMBOL(param_ops_string); | |
542 | ||
1da177e4 | 543 | /* sysfs output in /sys/modules/XYZ/parameters/ */ |
350f8258 EY |
544 | #define to_module_attr(n) container_of(n, struct module_attribute, attr) |
545 | #define to_module_kobject(n) container_of(n, struct module_kobject, kobj) | |
1da177e4 | 546 | |
1da177e4 LT |
547 | struct param_attribute |
548 | { | |
549 | struct module_attribute mattr; | |
9bbb9e5a | 550 | const struct kernel_param *param; |
1da177e4 LT |
551 | }; |
552 | ||
553 | struct module_param_attrs | |
554 | { | |
9b473de8 | 555 | unsigned int num; |
1da177e4 LT |
556 | struct attribute_group grp; |
557 | struct param_attribute attrs[0]; | |
558 | }; | |
559 | ||
ef665c1a | 560 | #ifdef CONFIG_SYSFS |
350f8258 | 561 | #define to_param_attr(n) container_of(n, struct param_attribute, mattr) |
1da177e4 LT |
562 | |
563 | static ssize_t param_attr_show(struct module_attribute *mattr, | |
4befb026 | 564 | struct module_kobject *mk, char *buf) |
1da177e4 LT |
565 | { |
566 | int count; | |
567 | struct param_attribute *attribute = to_param_attr(mattr); | |
568 | ||
9bbb9e5a | 569 | if (!attribute->param->ops->get) |
1da177e4 LT |
570 | return -EPERM; |
571 | ||
907b29eb | 572 | mutex_lock(¶m_lock); |
9bbb9e5a | 573 | count = attribute->param->ops->get(buf, attribute->param); |
907b29eb | 574 | mutex_unlock(¶m_lock); |
1da177e4 LT |
575 | if (count > 0) { |
576 | strcat(buf, "\n"); | |
577 | ++count; | |
578 | } | |
579 | return count; | |
580 | } | |
581 | ||
582 | /* sysfs always hands a nul-terminated string in buf. We rely on that. */ | |
583 | static ssize_t param_attr_store(struct module_attribute *mattr, | |
4befb026 | 584 | struct module_kobject *km, |
1da177e4 LT |
585 | const char *buf, size_t len) |
586 | { | |
587 | int err; | |
588 | struct param_attribute *attribute = to_param_attr(mattr); | |
589 | ||
9bbb9e5a | 590 | if (!attribute->param->ops->set) |
1da177e4 LT |
591 | return -EPERM; |
592 | ||
907b29eb | 593 | mutex_lock(¶m_lock); |
7a486d37 | 594 | param_check_unsafe(attribute->param); |
9bbb9e5a | 595 | err = attribute->param->ops->set(buf, attribute->param); |
907b29eb | 596 | mutex_unlock(¶m_lock); |
1da177e4 LT |
597 | if (!err) |
598 | return len; | |
599 | return err; | |
600 | } | |
ef665c1a | 601 | #endif |
1da177e4 LT |
602 | |
603 | #ifdef CONFIG_MODULES | |
604 | #define __modinit | |
605 | #else | |
606 | #define __modinit __init | |
607 | #endif | |
608 | ||
ef665c1a | 609 | #ifdef CONFIG_SYSFS |
907b29eb RR |
610 | void __kernel_param_lock(void) |
611 | { | |
612 | mutex_lock(¶m_lock); | |
613 | } | |
614 | EXPORT_SYMBOL(__kernel_param_lock); | |
615 | ||
616 | void __kernel_param_unlock(void) | |
617 | { | |
618 | mutex_unlock(¶m_lock); | |
619 | } | |
620 | EXPORT_SYMBOL(__kernel_param_unlock); | |
621 | ||
1da177e4 | 622 | /* |
9b473de8 RR |
623 | * add_sysfs_param - add a parameter to sysfs |
624 | * @mk: struct module_kobject | |
625 | * @kparam: the actual parameter definition to add to sysfs | |
626 | * @name: name of parameter | |
1da177e4 | 627 | * |
9b473de8 RR |
628 | * Create a kobject if for a (per-module) parameter if mp NULL, and |
629 | * create file in sysfs. Returns an error on out of memory. Always cleans up | |
630 | * if there's an error. | |
1da177e4 | 631 | */ |
9b473de8 | 632 | static __modinit int add_sysfs_param(struct module_kobject *mk, |
9bbb9e5a | 633 | const struct kernel_param *kp, |
9b473de8 | 634 | const char *name) |
1da177e4 | 635 | { |
18eb74fa RR |
636 | struct module_param_attrs *new_mp; |
637 | struct attribute **new_attrs; | |
638 | unsigned int i; | |
9b473de8 RR |
639 | |
640 | /* We don't bother calling this with invisible parameters. */ | |
641 | BUG_ON(!kp->perm); | |
642 | ||
643 | if (!mk->mp) { | |
18eb74fa RR |
644 | /* First allocation. */ |
645 | mk->mp = kzalloc(sizeof(*mk->mp), GFP_KERNEL); | |
646 | if (!mk->mp) | |
647 | return -ENOMEM; | |
648 | mk->mp->grp.name = "parameters"; | |
649 | /* NULL-terminated attribute array. */ | |
650 | mk->mp->grp.attrs = kzalloc(sizeof(mk->mp->grp.attrs[0]), | |
651 | GFP_KERNEL); | |
652 | /* Caller will cleanup via free_module_param_attrs */ | |
653 | if (!mk->mp->grp.attrs) | |
654 | return -ENOMEM; | |
9b473de8 | 655 | } |
1da177e4 | 656 | |
18eb74fa RR |
657 | /* Enlarge allocations. */ |
658 | new_mp = krealloc(mk->mp, | |
659 | sizeof(*mk->mp) + | |
660 | sizeof(mk->mp->attrs[0]) * (mk->mp->num + 1), | |
661 | GFP_KERNEL); | |
662 | if (!new_mp) | |
663 | return -ENOMEM; | |
664 | mk->mp = new_mp; | |
665 | ||
666 | /* Extra pointer for NULL terminator */ | |
667 | new_attrs = krealloc(mk->mp->grp.attrs, | |
668 | sizeof(mk->mp->grp.attrs[0]) * (mk->mp->num + 2), | |
669 | GFP_KERNEL); | |
670 | if (!new_attrs) | |
671 | return -ENOMEM; | |
672 | mk->mp->grp.attrs = new_attrs; | |
9b473de8 RR |
673 | |
674 | /* Tack new one on the end. */ | |
c772be52 | 675 | memset(&mk->mp->attrs[mk->mp->num], 0, sizeof(mk->mp->attrs[0])); |
18eb74fa RR |
676 | sysfs_attr_init(&mk->mp->attrs[mk->mp->num].mattr.attr); |
677 | mk->mp->attrs[mk->mp->num].param = kp; | |
678 | mk->mp->attrs[mk->mp->num].mattr.show = param_attr_show; | |
b0a65b0c KC |
679 | /* Do not allow runtime DAC changes to make param writable. */ |
680 | if ((kp->perm & (S_IWUSR | S_IWGRP | S_IWOTH)) != 0) | |
681 | mk->mp->attrs[mk->mp->num].mattr.store = param_attr_store; | |
574732c7 RR |
682 | else |
683 | mk->mp->attrs[mk->mp->num].mattr.store = NULL; | |
18eb74fa RR |
684 | mk->mp->attrs[mk->mp->num].mattr.attr.name = (char *)name; |
685 | mk->mp->attrs[mk->mp->num].mattr.attr.mode = kp->perm; | |
686 | mk->mp->num++; | |
9b473de8 RR |
687 | |
688 | /* Fix up all the pointers, since krealloc can move us */ | |
18eb74fa RR |
689 | for (i = 0; i < mk->mp->num; i++) |
690 | mk->mp->grp.attrs[i] = &mk->mp->attrs[i].mattr.attr; | |
691 | mk->mp->grp.attrs[mk->mp->num] = NULL; | |
9b473de8 | 692 | return 0; |
9b473de8 | 693 | } |
1da177e4 | 694 | |
d2441183 | 695 | #ifdef CONFIG_MODULES |
9b473de8 RR |
696 | static void free_module_param_attrs(struct module_kobject *mk) |
697 | { | |
18eb74fa RR |
698 | if (mk->mp) |
699 | kfree(mk->mp->grp.attrs); | |
9b473de8 RR |
700 | kfree(mk->mp); |
701 | mk->mp = NULL; | |
1da177e4 LT |
702 | } |
703 | ||
1da177e4 LT |
704 | /* |
705 | * module_param_sysfs_setup - setup sysfs support for one module | |
706 | * @mod: module | |
707 | * @kparam: module parameters (array) | |
708 | * @num_params: number of module parameters | |
709 | * | |
9b473de8 RR |
710 | * Adds sysfs entries for module parameters under |
711 | * /sys/module/[mod->name]/parameters/ | |
1da177e4 LT |
712 | */ |
713 | int module_param_sysfs_setup(struct module *mod, | |
9bbb9e5a | 714 | const struct kernel_param *kparam, |
1da177e4 LT |
715 | unsigned int num_params) |
716 | { | |
9b473de8 RR |
717 | int i, err; |
718 | bool params = false; | |
719 | ||
720 | for (i = 0; i < num_params; i++) { | |
721 | if (kparam[i].perm == 0) | |
722 | continue; | |
723 | err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name); | |
18eb74fa RR |
724 | if (err) { |
725 | free_module_param_attrs(&mod->mkobj); | |
9b473de8 | 726 | return err; |
18eb74fa | 727 | } |
9b473de8 RR |
728 | params = true; |
729 | } | |
1da177e4 | 730 | |
9b473de8 RR |
731 | if (!params) |
732 | return 0; | |
1da177e4 | 733 | |
9b473de8 RR |
734 | /* Create the param group. */ |
735 | err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
736 | if (err) | |
737 | free_module_param_attrs(&mod->mkobj); | |
738 | return err; | |
1da177e4 LT |
739 | } |
740 | ||
741 | /* | |
742 | * module_param_sysfs_remove - remove sysfs support for one module | |
743 | * @mod: module | |
744 | * | |
745 | * Remove sysfs entries for module parameters and the corresponding | |
746 | * kobject. | |
747 | */ | |
748 | void module_param_sysfs_remove(struct module *mod) | |
749 | { | |
9b473de8 RR |
750 | if (mod->mkobj.mp) { |
751 | sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
1da177e4 LT |
752 | /* We are positive that no one is using any param |
753 | * attrs at this point. Deallocate immediately. */ | |
9b473de8 | 754 | free_module_param_attrs(&mod->mkobj); |
1da177e4 LT |
755 | } |
756 | } | |
757 | #endif | |
758 | ||
e180a6b7 RR |
759 | void destroy_params(const struct kernel_param *params, unsigned num) |
760 | { | |
e6df34a4 RR |
761 | unsigned int i; |
762 | ||
763 | for (i = 0; i < num; i++) | |
764 | if (params[i].ops->free) | |
765 | params[i].ops->free(params[i].arg); | |
e180a6b7 RR |
766 | } |
767 | ||
e94965ed | 768 | static struct module_kobject * __init locate_module_kobject(const char *name) |
1da177e4 LT |
769 | { |
770 | struct module_kobject *mk; | |
9b473de8 RR |
771 | struct kobject *kobj; |
772 | int err; | |
1da177e4 | 773 | |
9b473de8 RR |
774 | kobj = kset_find_obj(module_kset, name); |
775 | if (kobj) { | |
9b473de8 | 776 | mk = to_module_kobject(kobj); |
9b473de8 RR |
777 | } else { |
778 | mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL); | |
779 | BUG_ON(!mk); | |
780 | ||
781 | mk->mod = THIS_MODULE; | |
782 | mk->kobj.kset = module_kset; | |
783 | err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL, | |
784 | "%s", name); | |
88bfa324 KS |
785 | #ifdef CONFIG_MODULES |
786 | if (!err) | |
787 | err = sysfs_create_file(&mk->kobj, &module_uevent.attr); | |
788 | #endif | |
9b473de8 RR |
789 | if (err) { |
790 | kobject_put(&mk->kobj); | |
b5f3abf9 | 791 | pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n", |
e94965ed | 792 | name, err); |
e94965ed | 793 | return NULL; |
9b473de8 | 794 | } |
e94965ed DT |
795 | |
796 | /* So that we hold reference in both cases. */ | |
9b473de8 | 797 | kobject_get(&mk->kobj); |
74c5b597 | 798 | } |
9b473de8 | 799 | |
e94965ed DT |
800 | return mk; |
801 | } | |
802 | ||
803 | static void __init kernel_add_sysfs_param(const char *name, | |
63a12d9d | 804 | const struct kernel_param *kparam, |
e94965ed DT |
805 | unsigned int name_skip) |
806 | { | |
807 | struct module_kobject *mk; | |
808 | int err; | |
809 | ||
810 | mk = locate_module_kobject(name); | |
811 | if (!mk) | |
812 | return; | |
813 | ||
814 | /* We need to remove old parameters before adding more. */ | |
815 | if (mk->mp) | |
816 | sysfs_remove_group(&mk->kobj, &mk->mp->grp); | |
817 | ||
9b473de8 RR |
818 | /* These should not fail at boot. */ |
819 | err = add_sysfs_param(mk, kparam, kparam->name + name_skip); | |
820 | BUG_ON(err); | |
821 | err = sysfs_create_group(&mk->kobj, &mk->mp->grp); | |
822 | BUG_ON(err); | |
f30c53a8 | 823 | kobject_uevent(&mk->kobj, KOBJ_ADD); |
9b473de8 | 824 | kobject_put(&mk->kobj); |
1da177e4 LT |
825 | } |
826 | ||
827 | /* | |
b634d130 | 828 | * param_sysfs_builtin - add sysfs parameters for built-in modules |
1da177e4 LT |
829 | * |
830 | * Add module_parameters to sysfs for "modules" built into the kernel. | |
831 | * | |
832 | * The "module" name (KBUILD_MODNAME) is stored before a dot, the | |
833 | * "parameter" name is stored behind a dot in kernel_param->name. So, | |
834 | * extract the "module" name for all built-in kernel_param-eters, | |
9b473de8 | 835 | * and for all who have the same, call kernel_add_sysfs_param. |
1da177e4 LT |
836 | */ |
837 | static void __init param_sysfs_builtin(void) | |
838 | { | |
63a12d9d | 839 | const struct kernel_param *kp; |
9b473de8 RR |
840 | unsigned int name_len; |
841 | char modname[MODULE_NAME_LEN]; | |
1da177e4 | 842 | |
9b473de8 | 843 | for (kp = __start___param; kp < __stop___param; kp++) { |
1da177e4 LT |
844 | char *dot; |
845 | ||
9b473de8 RR |
846 | if (kp->perm == 0) |
847 | continue; | |
1da177e4 | 848 | |
730b69d2 | 849 | dot = strchr(kp->name, '.'); |
1da177e4 | 850 | if (!dot) { |
67e67cea RR |
851 | /* This happens for core_param() */ |
852 | strcpy(modname, "kernel"); | |
853 | name_len = 0; | |
854 | } else { | |
855 | name_len = dot - kp->name + 1; | |
856 | strlcpy(modname, kp->name, name_len); | |
1da177e4 | 857 | } |
67e67cea | 858 | kernel_add_sysfs_param(modname, kp, name_len); |
1da177e4 | 859 | } |
1da177e4 LT |
860 | } |
861 | ||
e94965ed | 862 | ssize_t __modver_version_show(struct module_attribute *mattr, |
4befb026 | 863 | struct module_kobject *mk, char *buf) |
e94965ed DT |
864 | { |
865 | struct module_version_attribute *vattr = | |
866 | container_of(mattr, struct module_version_attribute, mattr); | |
867 | ||
f4940ab7 | 868 | return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version); |
e94965ed DT |
869 | } |
870 | ||
b4bc8428 DT |
871 | extern const struct module_version_attribute *__start___modver[]; |
872 | extern const struct module_version_attribute *__stop___modver[]; | |
e94965ed DT |
873 | |
874 | static void __init version_sysfs_builtin(void) | |
875 | { | |
b4bc8428 | 876 | const struct module_version_attribute **p; |
e94965ed DT |
877 | struct module_kobject *mk; |
878 | int err; | |
879 | ||
b4bc8428 DT |
880 | for (p = __start___modver; p < __stop___modver; p++) { |
881 | const struct module_version_attribute *vattr = *p; | |
882 | ||
e94965ed DT |
883 | mk = locate_module_kobject(vattr->module_name); |
884 | if (mk) { | |
885 | err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr); | |
886 | kobject_uevent(&mk->kobj, KOBJ_ADD); | |
887 | kobject_put(&mk->kobj); | |
888 | } | |
889 | } | |
890 | } | |
1da177e4 LT |
891 | |
892 | /* module-related sysfs stuff */ | |
1da177e4 | 893 | |
1da177e4 LT |
894 | static ssize_t module_attr_show(struct kobject *kobj, |
895 | struct attribute *attr, | |
896 | char *buf) | |
897 | { | |
898 | struct module_attribute *attribute; | |
899 | struct module_kobject *mk; | |
900 | int ret; | |
901 | ||
902 | attribute = to_module_attr(attr); | |
903 | mk = to_module_kobject(kobj); | |
904 | ||
905 | if (!attribute->show) | |
70f2817a | 906 | return -EIO; |
1da177e4 | 907 | |
4befb026 | 908 | ret = attribute->show(attribute, mk, buf); |
1da177e4 | 909 | |
1da177e4 LT |
910 | return ret; |
911 | } | |
912 | ||
913 | static ssize_t module_attr_store(struct kobject *kobj, | |
914 | struct attribute *attr, | |
915 | const char *buf, size_t len) | |
916 | { | |
917 | struct module_attribute *attribute; | |
918 | struct module_kobject *mk; | |
919 | int ret; | |
920 | ||
921 | attribute = to_module_attr(attr); | |
922 | mk = to_module_kobject(kobj); | |
923 | ||
924 | if (!attribute->store) | |
70f2817a | 925 | return -EIO; |
1da177e4 | 926 | |
4befb026 | 927 | ret = attribute->store(attribute, mk, buf, len); |
1da177e4 | 928 | |
1da177e4 LT |
929 | return ret; |
930 | } | |
931 | ||
52cf25d0 | 932 | static const struct sysfs_ops module_sysfs_ops = { |
1da177e4 LT |
933 | .show = module_attr_show, |
934 | .store = module_attr_store, | |
935 | }; | |
936 | ||
270a6c4c KS |
937 | static int uevent_filter(struct kset *kset, struct kobject *kobj) |
938 | { | |
939 | struct kobj_type *ktype = get_ktype(kobj); | |
940 | ||
941 | if (ktype == &module_ktype) | |
942 | return 1; | |
943 | return 0; | |
944 | } | |
945 | ||
9cd43611 | 946 | static const struct kset_uevent_ops module_uevent_ops = { |
270a6c4c KS |
947 | .filter = uevent_filter, |
948 | }; | |
949 | ||
7405c1e1 | 950 | struct kset *module_kset; |
823bccfc | 951 | int module_sysfs_initialized; |
1da177e4 | 952 | |
942e4431 LZ |
953 | static void module_kobj_release(struct kobject *kobj) |
954 | { | |
955 | struct module_kobject *mk = to_module_kobject(kobj); | |
956 | complete(mk->kobj_completion); | |
957 | } | |
958 | ||
7405c1e1 | 959 | struct kobj_type module_ktype = { |
942e4431 | 960 | .release = module_kobj_release, |
1da177e4 LT |
961 | .sysfs_ops = &module_sysfs_ops, |
962 | }; | |
963 | ||
1da177e4 LT |
964 | /* |
965 | * param_sysfs_init - wrapper for built-in params support | |
966 | */ | |
967 | static int __init param_sysfs_init(void) | |
968 | { | |
7405c1e1 GKH |
969 | module_kset = kset_create_and_add("module", &module_uevent_ops, NULL); |
970 | if (!module_kset) { | |
971 | printk(KERN_WARNING "%s (%d): error creating kset\n", | |
972 | __FILE__, __LINE__); | |
973 | return -ENOMEM; | |
d8c7649e | 974 | } |
823bccfc | 975 | module_sysfs_initialized = 1; |
1da177e4 | 976 | |
e94965ed | 977 | version_sysfs_builtin(); |
1da177e4 LT |
978 | param_sysfs_builtin(); |
979 | ||
980 | return 0; | |
981 | } | |
d10be6d1 | 982 | subsys_initcall(param_sysfs_init); |
1da177e4 | 983 | |
7405c1e1 | 984 | #endif /* CONFIG_SYSFS */ |