Commit | Line | Data |
---|---|---|
1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* Helpers for initial module or kernel cmdline parsing |
3 | Copyright (C) 2001 Rusty Russell. | |
4 | ||
1da177e4 | 5 | */ |
1da177e4 | 6 | #include <linux/kernel.h> |
def7b92e | 7 | #include <linux/kstrtox.h> |
1da177e4 LT |
8 | #include <linux/string.h> |
9 | #include <linux/errno.h> | |
10 | #include <linux/module.h> | |
63a12d9d | 11 | #include <linux/moduleparam.h> |
1da177e4 LT |
12 | #include <linux/device.h> |
13 | #include <linux/err.h> | |
4e57b681 | 14 | #include <linux/slab.h> |
26d052bf | 15 | #include <linux/ctype.h> |
20657f66 | 16 | #include <linux/security.h> |
1da177e4 | 17 | |
cf2fde7b | 18 | #ifdef CONFIG_SYSFS |
b51d23e4 | 19 | /* Protects all built-in parameters, modules use their own param_lock */ |
907b29eb RR |
20 | static DEFINE_MUTEX(param_lock); |
21 | ||
b51d23e4 | 22 | /* Use the module's mutex, or if built-in use the built-in mutex */ |
20bdc2cf | 23 | #ifdef CONFIG_MODULES |
b51d23e4 | 24 | #define KPARAM_MUTEX(mod) ((mod) ? &(mod)->param_lock : ¶m_lock) |
20bdc2cf SR |
25 | #else |
26 | #define KPARAM_MUTEX(mod) (¶m_lock) | |
27 | #endif | |
cf2fde7b RR |
28 | |
29 | static inline void check_kparam_locked(struct module *mod) | |
30 | { | |
31 | BUG_ON(!mutex_is_locked(KPARAM_MUTEX(mod))); | |
32 | } | |
33 | #else | |
34 | static inline void check_kparam_locked(struct module *mod) | |
35 | { | |
36 | } | |
37 | #endif /* !CONFIG_SYSFS */ | |
b51d23e4 | 38 | |
a1054322 RR |
39 | /* This just allows us to keep track of which parameters are kmalloced. */ |
40 | struct kmalloced_param { | |
41 | struct list_head list; | |
42 | char val[]; | |
43 | }; | |
a1054322 | 44 | static LIST_HEAD(kmalloced_params); |
b51d23e4 | 45 | static DEFINE_SPINLOCK(kmalloced_params_lock); |
a1054322 RR |
46 | |
47 | static void *kmalloc_parameter(unsigned int size) | |
48 | { | |
49 | struct kmalloced_param *p; | |
50 | ||
51 | p = kmalloc(sizeof(*p) + size, GFP_KERNEL); | |
52 | if (!p) | |
53 | return NULL; | |
54 | ||
b51d23e4 | 55 | spin_lock(&kmalloced_params_lock); |
a1054322 | 56 | list_add(&p->list, &kmalloced_params); |
b51d23e4 DS |
57 | spin_unlock(&kmalloced_params_lock); |
58 | ||
a1054322 RR |
59 | return p->val; |
60 | } | |
61 | ||
62 | /* Does nothing if parameter wasn't kmalloced above. */ | |
63 | static void maybe_kfree_parameter(void *param) | |
64 | { | |
65 | struct kmalloced_param *p; | |
66 | ||
b51d23e4 | 67 | spin_lock(&kmalloced_params_lock); |
a1054322 RR |
68 | list_for_each_entry(p, &kmalloced_params, list) { |
69 | if (p->val == param) { | |
70 | list_del(&p->list); | |
71 | kfree(p); | |
72 | break; | |
73 | } | |
74 | } | |
b51d23e4 | 75 | spin_unlock(&kmalloced_params_lock); |
a1054322 RR |
76 | } |
77 | ||
b1e4d20c | 78 | static char dash2underscore(char c) |
1da177e4 LT |
79 | { |
80 | if (c == '-') | |
81 | return '_'; | |
82 | return c; | |
83 | } | |
84 | ||
b1e4d20c | 85 | bool parameqn(const char *a, const char *b, size_t n) |
1da177e4 | 86 | { |
b1e4d20c MS |
87 | size_t i; |
88 | ||
89 | for (i = 0; i < n; i++) { | |
90 | if (dash2underscore(a[i]) != dash2underscore(b[i])) | |
91 | return false; | |
92 | } | |
93 | return true; | |
94 | } | |
95 | ||
96 | bool parameq(const char *a, const char *b) | |
97 | { | |
98 | return parameqn(a, b, strlen(a)+1); | |
1da177e4 LT |
99 | } |
100 | ||
20657f66 | 101 | static bool param_check_unsafe(const struct kernel_param *kp) |
7a486d37 | 102 | { |
20657f66 DH |
103 | if (kp->flags & KERNEL_PARAM_FL_HWPARAM && |
104 | security_locked_down(LOCKDOWN_MODULE_PARAMETERS)) | |
105 | return false; | |
106 | ||
7a486d37 | 107 | if (kp->flags & KERNEL_PARAM_FL_UNSAFE) { |
edc41b3c CW |
108 | pr_notice("Setting dangerous option %s - tainting kernel\n", |
109 | kp->name); | |
7a486d37 RR |
110 | add_taint(TAINT_USER, LOCKDEP_STILL_OK); |
111 | } | |
20657f66 DH |
112 | |
113 | return true; | |
7a486d37 RR |
114 | } |
115 | ||
1da177e4 LT |
116 | static int parse_one(char *param, |
117 | char *val, | |
9fb48c74 | 118 | const char *doing, |
914dcaa8 | 119 | const struct kernel_param *params, |
1da177e4 | 120 | unsigned num_params, |
026cee00 PM |
121 | s16 min_level, |
122 | s16 max_level, | |
12cd3cd8 | 123 | void *arg, parse_unknown_fn handle_unknown) |
1da177e4 LT |
124 | { |
125 | unsigned int i; | |
907b29eb | 126 | int err; |
1da177e4 LT |
127 | |
128 | /* Find parameter */ | |
129 | for (i = 0; i < num_params; i++) { | |
130 | if (parameq(param, params[i].name)) { | |
026cee00 PM |
131 | if (params[i].level < min_level |
132 | || params[i].level > max_level) | |
133 | return 0; | |
25985edc | 134 | /* No one handled NULL, so do it here. */ |
ab013c5f | 135 | if (!val && |
6a4c2643 | 136 | !(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG)) |
2e9fb995 | 137 | return -EINVAL; |
9fb48c74 JC |
138 | pr_debug("handling %s with %p\n", param, |
139 | params[i].ops->set); | |
b51d23e4 | 140 | kernel_param_lock(params[i].mod); |
20657f66 DH |
141 | if (param_check_unsafe(¶ms[i])) |
142 | err = params[i].ops->set(val, ¶ms[i]); | |
143 | else | |
144 | err = -EPERM; | |
b51d23e4 | 145 | kernel_param_unlock(params[i].mod); |
907b29eb | 146 | return err; |
1da177e4 LT |
147 | } |
148 | } | |
149 | ||
150 | if (handle_unknown) { | |
9fb48c74 | 151 | pr_debug("doing %s: %s='%s'\n", doing, param, val); |
ecc86170 | 152 | return handle_unknown(param, val, doing, arg); |
1da177e4 LT |
153 | } |
154 | ||
9fb48c74 | 155 | pr_debug("Unknown argument '%s'\n", param); |
1da177e4 LT |
156 | return -ENOENT; |
157 | } | |
158 | ||
1da177e4 | 159 | /* Args looks like "foo=bar,bar2 baz=fuz wiz". */ |
51e158c1 RR |
160 | char *parse_args(const char *doing, |
161 | char *args, | |
162 | const struct kernel_param *params, | |
163 | unsigned num, | |
164 | s16 min_level, | |
165 | s16 max_level, | |
12cd3cd8 | 166 | void *arg, parse_unknown_fn unknown) |
1da177e4 | 167 | { |
74b22c46 | 168 | char *param, *val, *err = NULL; |
1da177e4 | 169 | |
f36462f0 | 170 | /* Chew leading spaces */ |
e7d2860b | 171 | args = skip_spaces(args); |
f36462f0 | 172 | |
1ef9eaf2 | 173 | if (*args) |
9fb48c74 JC |
174 | pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args); |
175 | ||
1da177e4 LT |
176 | while (*args) { |
177 | int ret; | |
a416aba6 | 178 | int irq_was_disabled; |
1da177e4 LT |
179 | |
180 | args = next_arg(args, ¶m, &val); | |
51e158c1 RR |
181 | /* Stop at -- */ |
182 | if (!val && strcmp(param, "--") == 0) | |
74b22c46 | 183 | return err ?: args; |
a416aba6 | 184 | irq_was_disabled = irqs_disabled(); |
9fb48c74 | 185 | ret = parse_one(param, val, doing, params, num, |
ecc86170 | 186 | min_level, max_level, arg, unknown); |
b5f3abf9 JC |
187 | if (irq_was_disabled && !irqs_disabled()) |
188 | pr_warn("%s: option '%s' enabled irq's!\n", | |
189 | doing, param); | |
190 | ||
1da177e4 | 191 | switch (ret) { |
74b22c46 ON |
192 | case 0: |
193 | continue; | |
1da177e4 | 194 | case -ENOENT: |
b5f3abf9 | 195 | pr_err("%s: Unknown parameter `%s'\n", doing, param); |
74b22c46 | 196 | break; |
1da177e4 | 197 | case -ENOSPC: |
b5f3abf9 | 198 | pr_err("%s: `%s' too large for parameter `%s'\n", |
9fb48c74 | 199 | doing, val ?: "", param); |
1da177e4 LT |
200 | break; |
201 | default: | |
b5f3abf9 | 202 | pr_err("%s: `%s' invalid for parameter `%s'\n", |
9fb48c74 | 203 | doing, val ?: "", param); |
74b22c46 | 204 | break; |
1da177e4 | 205 | } |
74b22c46 ON |
206 | |
207 | err = ERR_PTR(ret); | |
1da177e4 LT |
208 | } |
209 | ||
74b22c46 | 210 | return err; |
1da177e4 LT |
211 | } |
212 | ||
213 | /* Lazy bastard, eh? */ | |
88a88b32 | 214 | #define STANDARD_PARAM_DEF(name, type, format, strtolfn) \ |
9bbb9e5a | 215 | int param_set_##name(const char *val, const struct kernel_param *kp) \ |
1da177e4 | 216 | { \ |
88a88b32 | 217 | return strtolfn(val, 0, (type *)kp->arg); \ |
1da177e4 | 218 | } \ |
9bbb9e5a | 219 | int param_get_##name(char *buffer, const struct kernel_param *kp) \ |
1da177e4 | 220 | { \ |
96802e6b | 221 | return scnprintf(buffer, PAGE_SIZE, format "\n", \ |
f4940ab7 | 222 | *((type *)kp->arg)); \ |
a14fe249 | 223 | } \ |
9c27847d | 224 | const struct kernel_param_ops param_ops_##name = { \ |
9bbb9e5a RR |
225 | .set = param_set_##name, \ |
226 | .get = param_get_##name, \ | |
227 | }; \ | |
a14fe249 | 228 | EXPORT_SYMBOL(param_set_##name); \ |
9bbb9e5a RR |
229 | EXPORT_SYMBOL(param_get_##name); \ |
230 | EXPORT_SYMBOL(param_ops_##name) | |
231 | ||
1da177e4 | 232 | |
7d836577 PM |
233 | STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8); |
234 | STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16); | |
235 | STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16); | |
236 | STANDARD_PARAM_DEF(int, int, "%i", kstrtoint); | |
237 | STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint); | |
238 | STANDARD_PARAM_DEF(long, long, "%li", kstrtol); | |
239 | STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul); | |
240 | STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull); | |
241 | STANDARD_PARAM_DEF(hexint, unsigned int, "%#08x", kstrtouint); | |
1da177e4 | 242 | |
2a14c9ae SG |
243 | int param_set_uint_minmax(const char *val, const struct kernel_param *kp, |
244 | unsigned int min, unsigned int max) | |
245 | { | |
246 | unsigned int num; | |
247 | int ret; | |
248 | ||
249 | if (!val) | |
250 | return -EINVAL; | |
251 | ret = kstrtouint(val, 0, &num); | |
252 | if (ret) | |
253 | return ret; | |
254 | if (num < min || num > max) | |
255 | return -EINVAL; | |
256 | *((unsigned int *)kp->arg) = num; | |
257 | return 0; | |
258 | } | |
259 | EXPORT_SYMBOL_GPL(param_set_uint_minmax); | |
260 | ||
9bbb9e5a | 261 | int param_set_charp(const char *val, const struct kernel_param *kp) |
1da177e4 | 262 | { |
1da177e4 | 263 | if (strlen(val) > 1024) { |
b5f3abf9 | 264 | pr_err("%s: string parameter too long\n", kp->name); |
1da177e4 LT |
265 | return -ENOSPC; |
266 | } | |
267 | ||
a1054322 RR |
268 | maybe_kfree_parameter(*(char **)kp->arg); |
269 | ||
270 | /* This is a hack. We can't kmalloc in early boot, and we | |
e180a6b7 RR |
271 | * don't need to; this mangled commandline is preserved. */ |
272 | if (slab_is_available()) { | |
a1054322 | 273 | *(char **)kp->arg = kmalloc_parameter(strlen(val)+1); |
d553ad86 | 274 | if (!*(char **)kp->arg) |
e180a6b7 | 275 | return -ENOMEM; |
a1054322 | 276 | strcpy(*(char **)kp->arg, val); |
e180a6b7 RR |
277 | } else |
278 | *(const char **)kp->arg = val; | |
279 | ||
1da177e4 LT |
280 | return 0; |
281 | } | |
a14fe249 | 282 | EXPORT_SYMBOL(param_set_charp); |
1da177e4 | 283 | |
9bbb9e5a | 284 | int param_get_charp(char *buffer, const struct kernel_param *kp) |
1da177e4 | 285 | { |
96802e6b | 286 | return scnprintf(buffer, PAGE_SIZE, "%s\n", *((char **)kp->arg)); |
1da177e4 | 287 | } |
a14fe249 | 288 | EXPORT_SYMBOL(param_get_charp); |
1da177e4 | 289 | |
3d9c637f | 290 | void param_free_charp(void *arg) |
a1054322 RR |
291 | { |
292 | maybe_kfree_parameter(*((char **)arg)); | |
293 | } | |
3d9c637f | 294 | EXPORT_SYMBOL(param_free_charp); |
a1054322 | 295 | |
9c27847d | 296 | const struct kernel_param_ops param_ops_charp = { |
9bbb9e5a RR |
297 | .set = param_set_charp, |
298 | .get = param_get_charp, | |
a1054322 | 299 | .free = param_free_charp, |
9bbb9e5a RR |
300 | }; |
301 | EXPORT_SYMBOL(param_ops_charp); | |
302 | ||
fddd5201 | 303 | /* Actually could be a bool or an int, for historical reasons. */ |
9bbb9e5a | 304 | int param_set_bool(const char *val, const struct kernel_param *kp) |
1da177e4 LT |
305 | { |
306 | /* No equals means "set"... */ | |
307 | if (!val) val = "1"; | |
308 | ||
309 | /* One of =[yYnN01] */ | |
def7b92e | 310 | return kstrtobool(val, kp->arg); |
1da177e4 | 311 | } |
a14fe249 | 312 | EXPORT_SYMBOL(param_set_bool); |
1da177e4 | 313 | |
9bbb9e5a | 314 | int param_get_bool(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
315 | { |
316 | /* Y and N chosen as being relatively non-coder friendly */ | |
96802e6b | 317 | return sprintf(buffer, "%c\n", *(bool *)kp->arg ? 'Y' : 'N'); |
1da177e4 | 318 | } |
a14fe249 | 319 | EXPORT_SYMBOL(param_get_bool); |
1da177e4 | 320 | |
9c27847d | 321 | const struct kernel_param_ops param_ops_bool = { |
6a4c2643 | 322 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
9bbb9e5a RR |
323 | .set = param_set_bool, |
324 | .get = param_get_bool, | |
325 | }; | |
326 | EXPORT_SYMBOL(param_ops_bool); | |
327 | ||
d19f05d8 LR |
328 | int param_set_bool_enable_only(const char *val, const struct kernel_param *kp) |
329 | { | |
9ce170ce | 330 | int err; |
d19f05d8 LR |
331 | bool new_value; |
332 | bool orig_value = *(bool *)kp->arg; | |
333 | struct kernel_param dummy_kp = *kp; | |
334 | ||
335 | dummy_kp.arg = &new_value; | |
336 | ||
337 | err = param_set_bool(val, &dummy_kp); | |
338 | if (err) | |
339 | return err; | |
340 | ||
341 | /* Don't let them unset it once it's set! */ | |
342 | if (!new_value && orig_value) | |
343 | return -EROFS; | |
344 | ||
345 | if (new_value) | |
346 | err = param_set_bool(val, kp); | |
347 | ||
348 | return err; | |
349 | } | |
350 | EXPORT_SYMBOL_GPL(param_set_bool_enable_only); | |
351 | ||
352 | const struct kernel_param_ops param_ops_bool_enable_only = { | |
353 | .flags = KERNEL_PARAM_OPS_FL_NOARG, | |
354 | .set = param_set_bool_enable_only, | |
355 | .get = param_get_bool, | |
356 | }; | |
154be21c | 357 | EXPORT_SYMBOL_GPL(param_ops_bool_enable_only); |
d19f05d8 | 358 | |
fddd5201 | 359 | /* This one must be bool. */ |
9bbb9e5a | 360 | int param_set_invbool(const char *val, const struct kernel_param *kp) |
1da177e4 | 361 | { |
fddd5201 RR |
362 | int ret; |
363 | bool boolval; | |
22e48eaf | 364 | struct kernel_param dummy; |
1da177e4 | 365 | |
22e48eaf | 366 | dummy.arg = &boolval; |
1da177e4 LT |
367 | ret = param_set_bool(val, &dummy); |
368 | if (ret == 0) | |
9a71af2c | 369 | *(bool *)kp->arg = !boolval; |
1da177e4 LT |
370 | return ret; |
371 | } | |
a14fe249 | 372 | EXPORT_SYMBOL(param_set_invbool); |
1da177e4 | 373 | |
9bbb9e5a | 374 | int param_get_invbool(char *buffer, const struct kernel_param *kp) |
1da177e4 | 375 | { |
96802e6b | 376 | return sprintf(buffer, "%c\n", (*(bool *)kp->arg) ? 'N' : 'Y'); |
1da177e4 | 377 | } |
a14fe249 | 378 | EXPORT_SYMBOL(param_get_invbool); |
1da177e4 | 379 | |
9c27847d | 380 | const struct kernel_param_ops param_ops_invbool = { |
9bbb9e5a RR |
381 | .set = param_set_invbool, |
382 | .get = param_get_invbool, | |
383 | }; | |
384 | EXPORT_SYMBOL(param_ops_invbool); | |
385 | ||
69116f27 RR |
386 | int param_set_bint(const char *val, const struct kernel_param *kp) |
387 | { | |
5104b7d7 DS |
388 | /* Match bool exactly, by re-using it. */ |
389 | struct kernel_param boolkp = *kp; | |
69116f27 RR |
390 | bool v; |
391 | int ret; | |
392 | ||
69116f27 | 393 | boolkp.arg = &v; |
69116f27 RR |
394 | |
395 | ret = param_set_bool(val, &boolkp); | |
396 | if (ret == 0) | |
397 | *(int *)kp->arg = v; | |
398 | return ret; | |
399 | } | |
400 | EXPORT_SYMBOL(param_set_bint); | |
401 | ||
9c27847d | 402 | const struct kernel_param_ops param_ops_bint = { |
6a4c2643 | 403 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
69116f27 RR |
404 | .set = param_set_bint, |
405 | .get = param_get_int, | |
406 | }; | |
407 | EXPORT_SYMBOL(param_ops_bint); | |
408 | ||
9730b5b0 | 409 | /* We break the rule and mangle the string. */ |
b51d23e4 DS |
410 | static int param_array(struct module *mod, |
411 | const char *name, | |
9871728b AB |
412 | const char *val, |
413 | unsigned int min, unsigned int max, | |
414 | void *elem, int elemsize, | |
9bbb9e5a | 415 | int (*set)(const char *, const struct kernel_param *kp), |
026cee00 | 416 | s16 level, |
eb38a996 | 417 | unsigned int *num) |
1da177e4 LT |
418 | { |
419 | int ret; | |
420 | struct kernel_param kp; | |
421 | char save; | |
422 | ||
423 | /* Get the name right for errors. */ | |
424 | kp.name = name; | |
425 | kp.arg = elem; | |
026cee00 | 426 | kp.level = level; |
1da177e4 | 427 | |
1da177e4 LT |
428 | *num = 0; |
429 | /* We expect a comma-separated list of values. */ | |
430 | do { | |
431 | int len; | |
432 | ||
433 | if (*num == max) { | |
b5f3abf9 | 434 | pr_err("%s: can only take %i arguments\n", name, max); |
1da177e4 LT |
435 | return -EINVAL; |
436 | } | |
437 | len = strcspn(val, ","); | |
438 | ||
439 | /* nul-terminate and parse */ | |
440 | save = val[len]; | |
441 | ((char *)val)[len] = '\0'; | |
cf2fde7b | 442 | check_kparam_locked(mod); |
1da177e4 LT |
443 | ret = set(val, &kp); |
444 | ||
445 | if (ret != 0) | |
446 | return ret; | |
447 | kp.arg += elemsize; | |
448 | val += len+1; | |
449 | (*num)++; | |
450 | } while (save == ','); | |
451 | ||
452 | if (*num < min) { | |
b5f3abf9 | 453 | pr_err("%s: needs at least %i arguments\n", name, min); |
1da177e4 LT |
454 | return -EINVAL; |
455 | } | |
456 | return 0; | |
457 | } | |
458 | ||
9bbb9e5a | 459 | static int param_array_set(const char *val, const struct kernel_param *kp) |
1da177e4 | 460 | { |
22e48eaf | 461 | const struct kparam_array *arr = kp->arr; |
31143a12 | 462 | unsigned int temp_num; |
1da177e4 | 463 | |
b51d23e4 | 464 | return param_array(kp->mod, kp->name, val, 1, arr->max, arr->elem, |
026cee00 | 465 | arr->elemsize, arr->ops->set, kp->level, |
3c7d76e3 | 466 | arr->num ?: &temp_num); |
1da177e4 LT |
467 | } |
468 | ||
9bbb9e5a | 469 | static int param_array_get(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
470 | { |
471 | int i, off, ret; | |
22e48eaf | 472 | const struct kparam_array *arr = kp->arr; |
5104b7d7 | 473 | struct kernel_param p = *kp; |
1da177e4 | 474 | |
1da177e4 | 475 | for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) { |
96802e6b | 476 | /* Replace \n with comma */ |
1da177e4 | 477 | if (i) |
96802e6b | 478 | buffer[off - 1] = ','; |
1da177e4 | 479 | p.arg = arr->elem + arr->elemsize * i; |
cf2fde7b | 480 | check_kparam_locked(p.mod); |
9bbb9e5a | 481 | ret = arr->ops->get(buffer + off, &p); |
1da177e4 LT |
482 | if (ret < 0) |
483 | return ret; | |
484 | off += ret; | |
485 | } | |
486 | buffer[off] = '\0'; | |
487 | return off; | |
488 | } | |
489 | ||
e6df34a4 RR |
490 | static void param_array_free(void *arg) |
491 | { | |
492 | unsigned int i; | |
493 | const struct kparam_array *arr = arg; | |
494 | ||
495 | if (arr->ops->free) | |
496 | for (i = 0; i < (arr->num ? *arr->num : arr->max); i++) | |
497 | arr->ops->free(arr->elem + arr->elemsize * i); | |
498 | } | |
499 | ||
9c27847d | 500 | const struct kernel_param_ops param_array_ops = { |
9bbb9e5a RR |
501 | .set = param_array_set, |
502 | .get = param_array_get, | |
e6df34a4 | 503 | .free = param_array_free, |
9bbb9e5a RR |
504 | }; |
505 | EXPORT_SYMBOL(param_array_ops); | |
506 | ||
507 | int param_set_copystring(const char *val, const struct kernel_param *kp) | |
1da177e4 | 508 | { |
22e48eaf | 509 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
510 | |
511 | if (strlen(val)+1 > kps->maxlen) { | |
b5f3abf9 | 512 | pr_err("%s: string doesn't fit in %u chars.\n", |
1da177e4 LT |
513 | kp->name, kps->maxlen-1); |
514 | return -ENOSPC; | |
515 | } | |
516 | strcpy(kps->string, val); | |
517 | return 0; | |
518 | } | |
a14fe249 | 519 | EXPORT_SYMBOL(param_set_copystring); |
1da177e4 | 520 | |
9bbb9e5a | 521 | int param_get_string(char *buffer, const struct kernel_param *kp) |
1da177e4 | 522 | { |
22e48eaf | 523 | const struct kparam_string *kps = kp->str; |
96802e6b | 524 | return scnprintf(buffer, PAGE_SIZE, "%s\n", kps->string); |
1da177e4 | 525 | } |
a14fe249 | 526 | EXPORT_SYMBOL(param_get_string); |
1da177e4 | 527 | |
9c27847d | 528 | const struct kernel_param_ops param_ops_string = { |
9bbb9e5a RR |
529 | .set = param_set_copystring, |
530 | .get = param_get_string, | |
531 | }; | |
532 | EXPORT_SYMBOL(param_ops_string); | |
533 | ||
1da177e4 | 534 | /* sysfs output in /sys/modules/XYZ/parameters/ */ |
350f8258 EY |
535 | #define to_module_attr(n) container_of(n, struct module_attribute, attr) |
536 | #define to_module_kobject(n) container_of(n, struct module_kobject, kobj) | |
1da177e4 | 537 | |
1da177e4 LT |
538 | struct param_attribute |
539 | { | |
540 | struct module_attribute mattr; | |
9bbb9e5a | 541 | const struct kernel_param *param; |
1da177e4 LT |
542 | }; |
543 | ||
544 | struct module_param_attrs | |
545 | { | |
9b473de8 | 546 | unsigned int num; |
1da177e4 | 547 | struct attribute_group grp; |
fa29c9c1 | 548 | struct param_attribute attrs[]; |
1da177e4 LT |
549 | }; |
550 | ||
ef665c1a | 551 | #ifdef CONFIG_SYSFS |
350f8258 | 552 | #define to_param_attr(n) container_of(n, struct param_attribute, mattr) |
1da177e4 LT |
553 | |
554 | static ssize_t param_attr_show(struct module_attribute *mattr, | |
4befb026 | 555 | struct module_kobject *mk, char *buf) |
1da177e4 LT |
556 | { |
557 | int count; | |
558 | struct param_attribute *attribute = to_param_attr(mattr); | |
559 | ||
9bbb9e5a | 560 | if (!attribute->param->ops->get) |
1da177e4 LT |
561 | return -EPERM; |
562 | ||
b51d23e4 | 563 | kernel_param_lock(mk->mod); |
9bbb9e5a | 564 | count = attribute->param->ops->get(buf, attribute->param); |
b51d23e4 | 565 | kernel_param_unlock(mk->mod); |
1da177e4 LT |
566 | return count; |
567 | } | |
568 | ||
569 | /* sysfs always hands a nul-terminated string in buf. We rely on that. */ | |
570 | static ssize_t param_attr_store(struct module_attribute *mattr, | |
b51d23e4 | 571 | struct module_kobject *mk, |
1da177e4 LT |
572 | const char *buf, size_t len) |
573 | { | |
574 | int err; | |
575 | struct param_attribute *attribute = to_param_attr(mattr); | |
576 | ||
9bbb9e5a | 577 | if (!attribute->param->ops->set) |
1da177e4 LT |
578 | return -EPERM; |
579 | ||
b51d23e4 | 580 | kernel_param_lock(mk->mod); |
20657f66 DH |
581 | if (param_check_unsafe(attribute->param)) |
582 | err = attribute->param->ops->set(buf, attribute->param); | |
583 | else | |
584 | err = -EPERM; | |
b51d23e4 | 585 | kernel_param_unlock(mk->mod); |
1da177e4 LT |
586 | if (!err) |
587 | return len; | |
588 | return err; | |
589 | } | |
ef665c1a | 590 | #endif |
1da177e4 LT |
591 | |
592 | #ifdef CONFIG_MODULES | |
593 | #define __modinit | |
594 | #else | |
595 | #define __modinit __init | |
596 | #endif | |
597 | ||
ef665c1a | 598 | #ifdef CONFIG_SYSFS |
b51d23e4 | 599 | void kernel_param_lock(struct module *mod) |
907b29eb | 600 | { |
b51d23e4 | 601 | mutex_lock(KPARAM_MUTEX(mod)); |
907b29eb | 602 | } |
907b29eb | 603 | |
b51d23e4 | 604 | void kernel_param_unlock(struct module *mod) |
907b29eb | 605 | { |
b51d23e4 | 606 | mutex_unlock(KPARAM_MUTEX(mod)); |
907b29eb | 607 | } |
b51d23e4 | 608 | |
b51d23e4 DS |
609 | EXPORT_SYMBOL(kernel_param_lock); |
610 | EXPORT_SYMBOL(kernel_param_unlock); | |
907b29eb | 611 | |
1da177e4 | 612 | /* |
9b473de8 RR |
613 | * add_sysfs_param - add a parameter to sysfs |
614 | * @mk: struct module_kobject | |
630cc2b3 | 615 | * @kp: the actual parameter definition to add to sysfs |
9b473de8 | 616 | * @name: name of parameter |
1da177e4 | 617 | * |
9b473de8 RR |
618 | * Create a kobject if for a (per-module) parameter if mp NULL, and |
619 | * create file in sysfs. Returns an error on out of memory. Always cleans up | |
620 | * if there's an error. | |
1da177e4 | 621 | */ |
9b473de8 | 622 | static __modinit int add_sysfs_param(struct module_kobject *mk, |
9bbb9e5a | 623 | const struct kernel_param *kp, |
9b473de8 | 624 | const char *name) |
1da177e4 | 625 | { |
18eb74fa RR |
626 | struct module_param_attrs *new_mp; |
627 | struct attribute **new_attrs; | |
628 | unsigned int i; | |
9b473de8 RR |
629 | |
630 | /* We don't bother calling this with invisible parameters. */ | |
631 | BUG_ON(!kp->perm); | |
632 | ||
633 | if (!mk->mp) { | |
18eb74fa RR |
634 | /* First allocation. */ |
635 | mk->mp = kzalloc(sizeof(*mk->mp), GFP_KERNEL); | |
636 | if (!mk->mp) | |
637 | return -ENOMEM; | |
638 | mk->mp->grp.name = "parameters"; | |
639 | /* NULL-terminated attribute array. */ | |
640 | mk->mp->grp.attrs = kzalloc(sizeof(mk->mp->grp.attrs[0]), | |
641 | GFP_KERNEL); | |
642 | /* Caller will cleanup via free_module_param_attrs */ | |
643 | if (!mk->mp->grp.attrs) | |
644 | return -ENOMEM; | |
9b473de8 | 645 | } |
1da177e4 | 646 | |
18eb74fa RR |
647 | /* Enlarge allocations. */ |
648 | new_mp = krealloc(mk->mp, | |
649 | sizeof(*mk->mp) + | |
650 | sizeof(mk->mp->attrs[0]) * (mk->mp->num + 1), | |
651 | GFP_KERNEL); | |
652 | if (!new_mp) | |
653 | return -ENOMEM; | |
654 | mk->mp = new_mp; | |
655 | ||
656 | /* Extra pointer for NULL terminator */ | |
657 | new_attrs = krealloc(mk->mp->grp.attrs, | |
658 | sizeof(mk->mp->grp.attrs[0]) * (mk->mp->num + 2), | |
659 | GFP_KERNEL); | |
660 | if (!new_attrs) | |
661 | return -ENOMEM; | |
662 | mk->mp->grp.attrs = new_attrs; | |
9b473de8 RR |
663 | |
664 | /* Tack new one on the end. */ | |
c772be52 | 665 | memset(&mk->mp->attrs[mk->mp->num], 0, sizeof(mk->mp->attrs[0])); |
18eb74fa RR |
666 | sysfs_attr_init(&mk->mp->attrs[mk->mp->num].mattr.attr); |
667 | mk->mp->attrs[mk->mp->num].param = kp; | |
668 | mk->mp->attrs[mk->mp->num].mattr.show = param_attr_show; | |
b0a65b0c KC |
669 | /* Do not allow runtime DAC changes to make param writable. */ |
670 | if ((kp->perm & (S_IWUSR | S_IWGRP | S_IWOTH)) != 0) | |
671 | mk->mp->attrs[mk->mp->num].mattr.store = param_attr_store; | |
574732c7 RR |
672 | else |
673 | mk->mp->attrs[mk->mp->num].mattr.store = NULL; | |
18eb74fa RR |
674 | mk->mp->attrs[mk->mp->num].mattr.attr.name = (char *)name; |
675 | mk->mp->attrs[mk->mp->num].mattr.attr.mode = kp->perm; | |
676 | mk->mp->num++; | |
9b473de8 RR |
677 | |
678 | /* Fix up all the pointers, since krealloc can move us */ | |
18eb74fa RR |
679 | for (i = 0; i < mk->mp->num; i++) |
680 | mk->mp->grp.attrs[i] = &mk->mp->attrs[i].mattr.attr; | |
681 | mk->mp->grp.attrs[mk->mp->num] = NULL; | |
9b473de8 | 682 | return 0; |
9b473de8 | 683 | } |
1da177e4 | 684 | |
d2441183 | 685 | #ifdef CONFIG_MODULES |
9b473de8 RR |
686 | static void free_module_param_attrs(struct module_kobject *mk) |
687 | { | |
18eb74fa RR |
688 | if (mk->mp) |
689 | kfree(mk->mp->grp.attrs); | |
9b473de8 RR |
690 | kfree(mk->mp); |
691 | mk->mp = NULL; | |
1da177e4 LT |
692 | } |
693 | ||
1da177e4 LT |
694 | /* |
695 | * module_param_sysfs_setup - setup sysfs support for one module | |
696 | * @mod: module | |
697 | * @kparam: module parameters (array) | |
698 | * @num_params: number of module parameters | |
699 | * | |
9b473de8 RR |
700 | * Adds sysfs entries for module parameters under |
701 | * /sys/module/[mod->name]/parameters/ | |
1da177e4 LT |
702 | */ |
703 | int module_param_sysfs_setup(struct module *mod, | |
9bbb9e5a | 704 | const struct kernel_param *kparam, |
1da177e4 LT |
705 | unsigned int num_params) |
706 | { | |
9b473de8 RR |
707 | int i, err; |
708 | bool params = false; | |
709 | ||
710 | for (i = 0; i < num_params; i++) { | |
711 | if (kparam[i].perm == 0) | |
712 | continue; | |
713 | err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name); | |
18eb74fa RR |
714 | if (err) { |
715 | free_module_param_attrs(&mod->mkobj); | |
9b473de8 | 716 | return err; |
18eb74fa | 717 | } |
9b473de8 RR |
718 | params = true; |
719 | } | |
1da177e4 | 720 | |
9b473de8 RR |
721 | if (!params) |
722 | return 0; | |
1da177e4 | 723 | |
9b473de8 RR |
724 | /* Create the param group. */ |
725 | err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
726 | if (err) | |
727 | free_module_param_attrs(&mod->mkobj); | |
728 | return err; | |
1da177e4 LT |
729 | } |
730 | ||
731 | /* | |
732 | * module_param_sysfs_remove - remove sysfs support for one module | |
733 | * @mod: module | |
734 | * | |
735 | * Remove sysfs entries for module parameters and the corresponding | |
736 | * kobject. | |
737 | */ | |
738 | void module_param_sysfs_remove(struct module *mod) | |
739 | { | |
9b473de8 RR |
740 | if (mod->mkobj.mp) { |
741 | sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
1da177e4 LT |
742 | /* We are positive that no one is using any param |
743 | * attrs at this point. Deallocate immediately. */ | |
9b473de8 | 744 | free_module_param_attrs(&mod->mkobj); |
1da177e4 LT |
745 | } |
746 | } | |
747 | #endif | |
748 | ||
e180a6b7 RR |
749 | void destroy_params(const struct kernel_param *params, unsigned num) |
750 | { | |
e6df34a4 RR |
751 | unsigned int i; |
752 | ||
753 | for (i = 0; i < num; i++) | |
754 | if (params[i].ops->free) | |
755 | params[i].ops->free(params[i].arg); | |
e180a6b7 RR |
756 | } |
757 | ||
e94965ed | 758 | static struct module_kobject * __init locate_module_kobject(const char *name) |
1da177e4 LT |
759 | { |
760 | struct module_kobject *mk; | |
9b473de8 RR |
761 | struct kobject *kobj; |
762 | int err; | |
1da177e4 | 763 | |
9b473de8 RR |
764 | kobj = kset_find_obj(module_kset, name); |
765 | if (kobj) { | |
9b473de8 | 766 | mk = to_module_kobject(kobj); |
9b473de8 RR |
767 | } else { |
768 | mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL); | |
769 | BUG_ON(!mk); | |
770 | ||
771 | mk->mod = THIS_MODULE; | |
772 | mk->kobj.kset = module_kset; | |
773 | err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL, | |
774 | "%s", name); | |
88bfa324 KS |
775 | #ifdef CONFIG_MODULES |
776 | if (!err) | |
777 | err = sysfs_create_file(&mk->kobj, &module_uevent.attr); | |
778 | #endif | |
9b473de8 RR |
779 | if (err) { |
780 | kobject_put(&mk->kobj); | |
b5f3abf9 | 781 | pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n", |
e94965ed | 782 | name, err); |
e94965ed | 783 | return NULL; |
9b473de8 | 784 | } |
e94965ed DT |
785 | |
786 | /* So that we hold reference in both cases. */ | |
9b473de8 | 787 | kobject_get(&mk->kobj); |
74c5b597 | 788 | } |
9b473de8 | 789 | |
e94965ed DT |
790 | return mk; |
791 | } | |
792 | ||
793 | static void __init kernel_add_sysfs_param(const char *name, | |
63a12d9d | 794 | const struct kernel_param *kparam, |
e94965ed DT |
795 | unsigned int name_skip) |
796 | { | |
797 | struct module_kobject *mk; | |
798 | int err; | |
799 | ||
800 | mk = locate_module_kobject(name); | |
801 | if (!mk) | |
802 | return; | |
803 | ||
804 | /* We need to remove old parameters before adding more. */ | |
805 | if (mk->mp) | |
806 | sysfs_remove_group(&mk->kobj, &mk->mp->grp); | |
807 | ||
9b473de8 RR |
808 | /* These should not fail at boot. */ |
809 | err = add_sysfs_param(mk, kparam, kparam->name + name_skip); | |
810 | BUG_ON(err); | |
811 | err = sysfs_create_group(&mk->kobj, &mk->mp->grp); | |
812 | BUG_ON(err); | |
f30c53a8 | 813 | kobject_uevent(&mk->kobj, KOBJ_ADD); |
9b473de8 | 814 | kobject_put(&mk->kobj); |
1da177e4 LT |
815 | } |
816 | ||
817 | /* | |
b634d130 | 818 | * param_sysfs_builtin - add sysfs parameters for built-in modules |
1da177e4 LT |
819 | * |
820 | * Add module_parameters to sysfs for "modules" built into the kernel. | |
821 | * | |
822 | * The "module" name (KBUILD_MODNAME) is stored before a dot, the | |
823 | * "parameter" name is stored behind a dot in kernel_param->name. So, | |
824 | * extract the "module" name for all built-in kernel_param-eters, | |
9b473de8 | 825 | * and for all who have the same, call kernel_add_sysfs_param. |
1da177e4 LT |
826 | */ |
827 | static void __init param_sysfs_builtin(void) | |
828 | { | |
63a12d9d | 829 | const struct kernel_param *kp; |
9b473de8 RR |
830 | unsigned int name_len; |
831 | char modname[MODULE_NAME_LEN]; | |
1da177e4 | 832 | |
9b473de8 | 833 | for (kp = __start___param; kp < __stop___param; kp++) { |
1da177e4 LT |
834 | char *dot; |
835 | ||
9b473de8 RR |
836 | if (kp->perm == 0) |
837 | continue; | |
1da177e4 | 838 | |
730b69d2 | 839 | dot = strchr(kp->name, '.'); |
1da177e4 | 840 | if (!dot) { |
67e67cea RR |
841 | /* This happens for core_param() */ |
842 | strcpy(modname, "kernel"); | |
843 | name_len = 0; | |
844 | } else { | |
845 | name_len = dot - kp->name + 1; | |
33457938 | 846 | strscpy(modname, kp->name, name_len); |
1da177e4 | 847 | } |
67e67cea | 848 | kernel_add_sysfs_param(modname, kp, name_len); |
1da177e4 | 849 | } |
1da177e4 LT |
850 | } |
851 | ||
e94965ed | 852 | ssize_t __modver_version_show(struct module_attribute *mattr, |
4befb026 | 853 | struct module_kobject *mk, char *buf) |
e94965ed DT |
854 | { |
855 | struct module_version_attribute *vattr = | |
856 | container_of(mattr, struct module_version_attribute, mattr); | |
857 | ||
f4940ab7 | 858 | return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version); |
e94965ed DT |
859 | } |
860 | ||
b112082c JH |
861 | extern const struct module_version_attribute __start___modver[]; |
862 | extern const struct module_version_attribute __stop___modver[]; | |
e94965ed DT |
863 | |
864 | static void __init version_sysfs_builtin(void) | |
865 | { | |
b112082c | 866 | const struct module_version_attribute *vattr; |
e94965ed DT |
867 | struct module_kobject *mk; |
868 | int err; | |
869 | ||
b112082c | 870 | for (vattr = __start___modver; vattr < __stop___modver; vattr++) { |
e94965ed DT |
871 | mk = locate_module_kobject(vattr->module_name); |
872 | if (mk) { | |
873 | err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr); | |
74c3dea3 | 874 | WARN_ON_ONCE(err); |
e94965ed DT |
875 | kobject_uevent(&mk->kobj, KOBJ_ADD); |
876 | kobject_put(&mk->kobj); | |
877 | } | |
878 | } | |
879 | } | |
1da177e4 LT |
880 | |
881 | /* module-related sysfs stuff */ | |
1da177e4 | 882 | |
1da177e4 LT |
883 | static ssize_t module_attr_show(struct kobject *kobj, |
884 | struct attribute *attr, | |
885 | char *buf) | |
886 | { | |
887 | struct module_attribute *attribute; | |
888 | struct module_kobject *mk; | |
889 | int ret; | |
890 | ||
891 | attribute = to_module_attr(attr); | |
892 | mk = to_module_kobject(kobj); | |
893 | ||
894 | if (!attribute->show) | |
70f2817a | 895 | return -EIO; |
1da177e4 | 896 | |
4befb026 | 897 | ret = attribute->show(attribute, mk, buf); |
1da177e4 | 898 | |
1da177e4 LT |
899 | return ret; |
900 | } | |
901 | ||
902 | static ssize_t module_attr_store(struct kobject *kobj, | |
903 | struct attribute *attr, | |
904 | const char *buf, size_t len) | |
905 | { | |
906 | struct module_attribute *attribute; | |
907 | struct module_kobject *mk; | |
908 | int ret; | |
909 | ||
910 | attribute = to_module_attr(attr); | |
911 | mk = to_module_kobject(kobj); | |
912 | ||
913 | if (!attribute->store) | |
70f2817a | 914 | return -EIO; |
1da177e4 | 915 | |
4befb026 | 916 | ret = attribute->store(attribute, mk, buf, len); |
1da177e4 | 917 | |
1da177e4 LT |
918 | return ret; |
919 | } | |
920 | ||
52cf25d0 | 921 | static const struct sysfs_ops module_sysfs_ops = { |
1da177e4 LT |
922 | .show = module_attr_show, |
923 | .store = module_attr_store, | |
924 | }; | |
925 | ||
c45a88bb | 926 | static int uevent_filter(const struct kobject *kobj) |
270a6c4c | 927 | { |
ee6d3dd4 | 928 | const struct kobj_type *ktype = get_ktype(kobj); |
270a6c4c KS |
929 | |
930 | if (ktype == &module_ktype) | |
931 | return 1; | |
932 | return 0; | |
933 | } | |
934 | ||
9cd43611 | 935 | static const struct kset_uevent_ops module_uevent_ops = { |
270a6c4c KS |
936 | .filter = uevent_filter, |
937 | }; | |
938 | ||
7405c1e1 | 939 | struct kset *module_kset; |
1da177e4 | 940 | |
942e4431 LZ |
941 | static void module_kobj_release(struct kobject *kobj) |
942 | { | |
943 | struct module_kobject *mk = to_module_kobject(kobj); | |
944 | complete(mk->kobj_completion); | |
945 | } | |
946 | ||
042edf1e | 947 | const struct kobj_type module_ktype = { |
942e4431 | 948 | .release = module_kobj_release, |
1da177e4 LT |
949 | .sysfs_ops = &module_sysfs_ops, |
950 | }; | |
951 | ||
1da177e4 | 952 | /* |
96a1a241 RV |
953 | * param_sysfs_init - create "module" kset |
954 | * | |
955 | * This must be done before the initramfs is unpacked and | |
956 | * request_module() thus becomes possible, because otherwise the | |
957 | * module load would fail in mod_sysfs_init. | |
1da177e4 LT |
958 | */ |
959 | static int __init param_sysfs_init(void) | |
960 | { | |
7405c1e1 GKH |
961 | module_kset = kset_create_and_add("module", &module_uevent_ops, NULL); |
962 | if (!module_kset) { | |
963 | printk(KERN_WARNING "%s (%d): error creating kset\n", | |
964 | __FILE__, __LINE__); | |
965 | return -ENOMEM; | |
d8c7649e | 966 | } |
1da177e4 | 967 | |
96a1a241 RV |
968 | return 0; |
969 | } | |
970 | subsys_initcall(param_sysfs_init); | |
971 | ||
972 | /* | |
973 | * param_sysfs_builtin_init - add sysfs version and parameter | |
974 | * attributes for built-in modules | |
975 | */ | |
976 | static int __init param_sysfs_builtin_init(void) | |
977 | { | |
978 | if (!module_kset) | |
979 | return -ENOMEM; | |
980 | ||
e94965ed | 981 | version_sysfs_builtin(); |
1da177e4 LT |
982 | param_sysfs_builtin(); |
983 | ||
984 | return 0; | |
985 | } | |
96a1a241 | 986 | late_initcall(param_sysfs_builtin_init); |
1da177e4 | 987 | |
7405c1e1 | 988 | #endif /* CONFIG_SYSFS */ |