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 LT |
6 | #include <linux/kernel.h> |
7 | #include <linux/string.h> | |
8 | #include <linux/errno.h> | |
9 | #include <linux/module.h> | |
63a12d9d | 10 | #include <linux/moduleparam.h> |
1da177e4 LT |
11 | #include <linux/device.h> |
12 | #include <linux/err.h> | |
4e57b681 | 13 | #include <linux/slab.h> |
26d052bf | 14 | #include <linux/ctype.h> |
20657f66 | 15 | #include <linux/security.h> |
1da177e4 | 16 | |
cf2fde7b | 17 | #ifdef CONFIG_SYSFS |
b51d23e4 | 18 | /* Protects all built-in parameters, modules use their own param_lock */ |
907b29eb RR |
19 | static DEFINE_MUTEX(param_lock); |
20 | ||
b51d23e4 | 21 | /* Use the module's mutex, or if built-in use the built-in mutex */ |
20bdc2cf | 22 | #ifdef CONFIG_MODULES |
b51d23e4 | 23 | #define KPARAM_MUTEX(mod) ((mod) ? &(mod)->param_lock : ¶m_lock) |
20bdc2cf SR |
24 | #else |
25 | #define KPARAM_MUTEX(mod) (¶m_lock) | |
26 | #endif | |
cf2fde7b RR |
27 | |
28 | static inline void check_kparam_locked(struct module *mod) | |
29 | { | |
30 | BUG_ON(!mutex_is_locked(KPARAM_MUTEX(mod))); | |
31 | } | |
32 | #else | |
33 | static inline void check_kparam_locked(struct module *mod) | |
34 | { | |
35 | } | |
36 | #endif /* !CONFIG_SYSFS */ | |
b51d23e4 | 37 | |
a1054322 RR |
38 | /* This just allows us to keep track of which parameters are kmalloced. */ |
39 | struct kmalloced_param { | |
40 | struct list_head list; | |
41 | char val[]; | |
42 | }; | |
a1054322 | 43 | static LIST_HEAD(kmalloced_params); |
b51d23e4 | 44 | static DEFINE_SPINLOCK(kmalloced_params_lock); |
a1054322 RR |
45 | |
46 | static void *kmalloc_parameter(unsigned int size) | |
47 | { | |
48 | struct kmalloced_param *p; | |
49 | ||
50 | p = kmalloc(sizeof(*p) + size, GFP_KERNEL); | |
51 | if (!p) | |
52 | return NULL; | |
53 | ||
b51d23e4 | 54 | spin_lock(&kmalloced_params_lock); |
a1054322 | 55 | list_add(&p->list, &kmalloced_params); |
b51d23e4 DS |
56 | spin_unlock(&kmalloced_params_lock); |
57 | ||
a1054322 RR |
58 | return p->val; |
59 | } | |
60 | ||
61 | /* Does nothing if parameter wasn't kmalloced above. */ | |
62 | static void maybe_kfree_parameter(void *param) | |
63 | { | |
64 | struct kmalloced_param *p; | |
65 | ||
b51d23e4 | 66 | spin_lock(&kmalloced_params_lock); |
a1054322 RR |
67 | list_for_each_entry(p, &kmalloced_params, list) { |
68 | if (p->val == param) { | |
69 | list_del(&p->list); | |
70 | kfree(p); | |
71 | break; | |
72 | } | |
73 | } | |
b51d23e4 | 74 | spin_unlock(&kmalloced_params_lock); |
a1054322 RR |
75 | } |
76 | ||
b1e4d20c | 77 | static char dash2underscore(char c) |
1da177e4 LT |
78 | { |
79 | if (c == '-') | |
80 | return '_'; | |
81 | return c; | |
82 | } | |
83 | ||
b1e4d20c | 84 | bool parameqn(const char *a, const char *b, size_t n) |
1da177e4 | 85 | { |
b1e4d20c MS |
86 | size_t i; |
87 | ||
88 | for (i = 0; i < n; i++) { | |
89 | if (dash2underscore(a[i]) != dash2underscore(b[i])) | |
90 | return false; | |
91 | } | |
92 | return true; | |
93 | } | |
94 | ||
95 | bool parameq(const char *a, const char *b) | |
96 | { | |
97 | return parameqn(a, b, strlen(a)+1); | |
1da177e4 LT |
98 | } |
99 | ||
20657f66 | 100 | static bool param_check_unsafe(const struct kernel_param *kp) |
7a486d37 | 101 | { |
20657f66 DH |
102 | if (kp->flags & KERNEL_PARAM_FL_HWPARAM && |
103 | security_locked_down(LOCKDOWN_MODULE_PARAMETERS)) | |
104 | return false; | |
105 | ||
7a486d37 | 106 | if (kp->flags & KERNEL_PARAM_FL_UNSAFE) { |
edc41b3c CW |
107 | pr_notice("Setting dangerous option %s - tainting kernel\n", |
108 | kp->name); | |
7a486d37 RR |
109 | add_taint(TAINT_USER, LOCKDEP_STILL_OK); |
110 | } | |
20657f66 DH |
111 | |
112 | return true; | |
7a486d37 RR |
113 | } |
114 | ||
1da177e4 LT |
115 | static int parse_one(char *param, |
116 | char *val, | |
9fb48c74 | 117 | const char *doing, |
914dcaa8 | 118 | const struct kernel_param *params, |
1da177e4 | 119 | unsigned num_params, |
026cee00 PM |
120 | s16 min_level, |
121 | s16 max_level, | |
ecc86170 | 122 | void *arg, |
9fb48c74 | 123 | int (*handle_unknown)(char *param, char *val, |
ecc86170 | 124 | const char *doing, void *arg)) |
1da177e4 LT |
125 | { |
126 | unsigned int i; | |
907b29eb | 127 | int err; |
1da177e4 LT |
128 | |
129 | /* Find parameter */ | |
130 | for (i = 0; i < num_params; i++) { | |
131 | if (parameq(param, params[i].name)) { | |
026cee00 PM |
132 | if (params[i].level < min_level |
133 | || params[i].level > max_level) | |
134 | return 0; | |
25985edc | 135 | /* No one handled NULL, so do it here. */ |
ab013c5f | 136 | if (!val && |
6a4c2643 | 137 | !(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG)) |
2e9fb995 | 138 | return -EINVAL; |
9fb48c74 JC |
139 | pr_debug("handling %s with %p\n", param, |
140 | params[i].ops->set); | |
b51d23e4 | 141 | kernel_param_lock(params[i].mod); |
20657f66 DH |
142 | if (param_check_unsafe(¶ms[i])) |
143 | err = params[i].ops->set(val, ¶ms[i]); | |
144 | else | |
145 | err = -EPERM; | |
b51d23e4 | 146 | kernel_param_unlock(params[i].mod); |
907b29eb | 147 | return err; |
1da177e4 LT |
148 | } |
149 | } | |
150 | ||
151 | if (handle_unknown) { | |
9fb48c74 | 152 | pr_debug("doing %s: %s='%s'\n", doing, param, val); |
ecc86170 | 153 | return handle_unknown(param, val, doing, arg); |
1da177e4 LT |
154 | } |
155 | ||
9fb48c74 | 156 | pr_debug("Unknown argument '%s'\n", param); |
1da177e4 LT |
157 | return -ENOENT; |
158 | } | |
159 | ||
1da177e4 | 160 | /* Args looks like "foo=bar,bar2 baz=fuz wiz". */ |
51e158c1 RR |
161 | char *parse_args(const char *doing, |
162 | char *args, | |
163 | const struct kernel_param *params, | |
164 | unsigned num, | |
165 | s16 min_level, | |
166 | s16 max_level, | |
ecc86170 LR |
167 | void *arg, |
168 | int (*unknown)(char *param, char *val, | |
169 | const char *doing, void *arg)) | |
1da177e4 | 170 | { |
74b22c46 | 171 | char *param, *val, *err = NULL; |
1da177e4 | 172 | |
f36462f0 | 173 | /* Chew leading spaces */ |
e7d2860b | 174 | args = skip_spaces(args); |
f36462f0 | 175 | |
1ef9eaf2 | 176 | if (*args) |
9fb48c74 JC |
177 | pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args); |
178 | ||
1da177e4 LT |
179 | while (*args) { |
180 | int ret; | |
a416aba6 | 181 | int irq_was_disabled; |
1da177e4 LT |
182 | |
183 | args = next_arg(args, ¶m, &val); | |
51e158c1 RR |
184 | /* Stop at -- */ |
185 | if (!val && strcmp(param, "--") == 0) | |
74b22c46 | 186 | return err ?: args; |
a416aba6 | 187 | irq_was_disabled = irqs_disabled(); |
9fb48c74 | 188 | ret = parse_one(param, val, doing, params, num, |
ecc86170 | 189 | min_level, max_level, arg, unknown); |
b5f3abf9 JC |
190 | if (irq_was_disabled && !irqs_disabled()) |
191 | pr_warn("%s: option '%s' enabled irq's!\n", | |
192 | doing, param); | |
193 | ||
1da177e4 | 194 | switch (ret) { |
74b22c46 ON |
195 | case 0: |
196 | continue; | |
1da177e4 | 197 | case -ENOENT: |
b5f3abf9 | 198 | pr_err("%s: Unknown parameter `%s'\n", doing, param); |
74b22c46 | 199 | break; |
1da177e4 | 200 | case -ENOSPC: |
b5f3abf9 | 201 | pr_err("%s: `%s' too large for parameter `%s'\n", |
9fb48c74 | 202 | doing, val ?: "", param); |
1da177e4 LT |
203 | break; |
204 | default: | |
b5f3abf9 | 205 | pr_err("%s: `%s' invalid for parameter `%s'\n", |
9fb48c74 | 206 | doing, val ?: "", param); |
74b22c46 | 207 | break; |
1da177e4 | 208 | } |
74b22c46 ON |
209 | |
210 | err = ERR_PTR(ret); | |
1da177e4 LT |
211 | } |
212 | ||
74b22c46 | 213 | return err; |
1da177e4 LT |
214 | } |
215 | ||
216 | /* Lazy bastard, eh? */ | |
88a88b32 | 217 | #define STANDARD_PARAM_DEF(name, type, format, strtolfn) \ |
9bbb9e5a | 218 | int param_set_##name(const char *val, const struct kernel_param *kp) \ |
1da177e4 | 219 | { \ |
88a88b32 | 220 | return strtolfn(val, 0, (type *)kp->arg); \ |
1da177e4 | 221 | } \ |
9bbb9e5a | 222 | int param_get_##name(char *buffer, const struct kernel_param *kp) \ |
1da177e4 | 223 | { \ |
96802e6b | 224 | return scnprintf(buffer, PAGE_SIZE, format "\n", \ |
f4940ab7 | 225 | *((type *)kp->arg)); \ |
a14fe249 | 226 | } \ |
9c27847d | 227 | const struct kernel_param_ops param_ops_##name = { \ |
9bbb9e5a RR |
228 | .set = param_set_##name, \ |
229 | .get = param_get_##name, \ | |
230 | }; \ | |
a14fe249 | 231 | EXPORT_SYMBOL(param_set_##name); \ |
9bbb9e5a RR |
232 | EXPORT_SYMBOL(param_get_##name); \ |
233 | EXPORT_SYMBOL(param_ops_##name) | |
234 | ||
1da177e4 | 235 | |
7d836577 PM |
236 | STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8); |
237 | STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16); | |
238 | STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16); | |
239 | STANDARD_PARAM_DEF(int, int, "%i", kstrtoint); | |
240 | STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint); | |
241 | STANDARD_PARAM_DEF(long, long, "%li", kstrtol); | |
242 | STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul); | |
243 | STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull); | |
244 | STANDARD_PARAM_DEF(hexint, unsigned int, "%#08x", kstrtouint); | |
1da177e4 | 245 | |
9bbb9e5a | 246 | int param_set_charp(const char *val, const struct kernel_param *kp) |
1da177e4 | 247 | { |
1da177e4 | 248 | if (strlen(val) > 1024) { |
b5f3abf9 | 249 | pr_err("%s: string parameter too long\n", kp->name); |
1da177e4 LT |
250 | return -ENOSPC; |
251 | } | |
252 | ||
a1054322 RR |
253 | maybe_kfree_parameter(*(char **)kp->arg); |
254 | ||
255 | /* This is a hack. We can't kmalloc in early boot, and we | |
e180a6b7 RR |
256 | * don't need to; this mangled commandline is preserved. */ |
257 | if (slab_is_available()) { | |
a1054322 | 258 | *(char **)kp->arg = kmalloc_parameter(strlen(val)+1); |
d553ad86 | 259 | if (!*(char **)kp->arg) |
e180a6b7 | 260 | return -ENOMEM; |
a1054322 | 261 | strcpy(*(char **)kp->arg, val); |
e180a6b7 RR |
262 | } else |
263 | *(const char **)kp->arg = val; | |
264 | ||
1da177e4 LT |
265 | return 0; |
266 | } | |
a14fe249 | 267 | EXPORT_SYMBOL(param_set_charp); |
1da177e4 | 268 | |
9bbb9e5a | 269 | int param_get_charp(char *buffer, const struct kernel_param *kp) |
1da177e4 | 270 | { |
96802e6b | 271 | return scnprintf(buffer, PAGE_SIZE, "%s\n", *((char **)kp->arg)); |
1da177e4 | 272 | } |
a14fe249 | 273 | EXPORT_SYMBOL(param_get_charp); |
1da177e4 | 274 | |
3d9c637f | 275 | void param_free_charp(void *arg) |
a1054322 RR |
276 | { |
277 | maybe_kfree_parameter(*((char **)arg)); | |
278 | } | |
3d9c637f | 279 | EXPORT_SYMBOL(param_free_charp); |
a1054322 | 280 | |
9c27847d | 281 | const struct kernel_param_ops param_ops_charp = { |
9bbb9e5a RR |
282 | .set = param_set_charp, |
283 | .get = param_get_charp, | |
a1054322 | 284 | .free = param_free_charp, |
9bbb9e5a RR |
285 | }; |
286 | EXPORT_SYMBOL(param_ops_charp); | |
287 | ||
fddd5201 | 288 | /* Actually could be a bool or an int, for historical reasons. */ |
9bbb9e5a | 289 | int param_set_bool(const char *val, const struct kernel_param *kp) |
1da177e4 LT |
290 | { |
291 | /* No equals means "set"... */ | |
292 | if (!val) val = "1"; | |
293 | ||
294 | /* One of =[yYnN01] */ | |
8b825281 | 295 | return strtobool(val, kp->arg); |
1da177e4 | 296 | } |
a14fe249 | 297 | EXPORT_SYMBOL(param_set_bool); |
1da177e4 | 298 | |
9bbb9e5a | 299 | int param_get_bool(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
300 | { |
301 | /* Y and N chosen as being relatively non-coder friendly */ | |
96802e6b | 302 | return sprintf(buffer, "%c\n", *(bool *)kp->arg ? 'Y' : 'N'); |
1da177e4 | 303 | } |
a14fe249 | 304 | EXPORT_SYMBOL(param_get_bool); |
1da177e4 | 305 | |
9c27847d | 306 | const struct kernel_param_ops param_ops_bool = { |
6a4c2643 | 307 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
9bbb9e5a RR |
308 | .set = param_set_bool, |
309 | .get = param_get_bool, | |
310 | }; | |
311 | EXPORT_SYMBOL(param_ops_bool); | |
312 | ||
d19f05d8 LR |
313 | int param_set_bool_enable_only(const char *val, const struct kernel_param *kp) |
314 | { | |
315 | int err = 0; | |
316 | bool new_value; | |
317 | bool orig_value = *(bool *)kp->arg; | |
318 | struct kernel_param dummy_kp = *kp; | |
319 | ||
320 | dummy_kp.arg = &new_value; | |
321 | ||
322 | err = param_set_bool(val, &dummy_kp); | |
323 | if (err) | |
324 | return err; | |
325 | ||
326 | /* Don't let them unset it once it's set! */ | |
327 | if (!new_value && orig_value) | |
328 | return -EROFS; | |
329 | ||
330 | if (new_value) | |
331 | err = param_set_bool(val, kp); | |
332 | ||
333 | return err; | |
334 | } | |
335 | EXPORT_SYMBOL_GPL(param_set_bool_enable_only); | |
336 | ||
337 | const struct kernel_param_ops param_ops_bool_enable_only = { | |
338 | .flags = KERNEL_PARAM_OPS_FL_NOARG, | |
339 | .set = param_set_bool_enable_only, | |
340 | .get = param_get_bool, | |
341 | }; | |
154be21c | 342 | EXPORT_SYMBOL_GPL(param_ops_bool_enable_only); |
d19f05d8 | 343 | |
fddd5201 | 344 | /* This one must be bool. */ |
9bbb9e5a | 345 | int param_set_invbool(const char *val, const struct kernel_param *kp) |
1da177e4 | 346 | { |
fddd5201 RR |
347 | int ret; |
348 | bool boolval; | |
22e48eaf | 349 | struct kernel_param dummy; |
1da177e4 | 350 | |
22e48eaf | 351 | dummy.arg = &boolval; |
1da177e4 LT |
352 | ret = param_set_bool(val, &dummy); |
353 | if (ret == 0) | |
9a71af2c | 354 | *(bool *)kp->arg = !boolval; |
1da177e4 LT |
355 | return ret; |
356 | } | |
a14fe249 | 357 | EXPORT_SYMBOL(param_set_invbool); |
1da177e4 | 358 | |
9bbb9e5a | 359 | int param_get_invbool(char *buffer, const struct kernel_param *kp) |
1da177e4 | 360 | { |
96802e6b | 361 | return sprintf(buffer, "%c\n", (*(bool *)kp->arg) ? 'N' : 'Y'); |
1da177e4 | 362 | } |
a14fe249 | 363 | EXPORT_SYMBOL(param_get_invbool); |
1da177e4 | 364 | |
9c27847d | 365 | const struct kernel_param_ops param_ops_invbool = { |
9bbb9e5a RR |
366 | .set = param_set_invbool, |
367 | .get = param_get_invbool, | |
368 | }; | |
369 | EXPORT_SYMBOL(param_ops_invbool); | |
370 | ||
69116f27 RR |
371 | int param_set_bint(const char *val, const struct kernel_param *kp) |
372 | { | |
5104b7d7 DS |
373 | /* Match bool exactly, by re-using it. */ |
374 | struct kernel_param boolkp = *kp; | |
69116f27 RR |
375 | bool v; |
376 | int ret; | |
377 | ||
69116f27 | 378 | boolkp.arg = &v; |
69116f27 RR |
379 | |
380 | ret = param_set_bool(val, &boolkp); | |
381 | if (ret == 0) | |
382 | *(int *)kp->arg = v; | |
383 | return ret; | |
384 | } | |
385 | EXPORT_SYMBOL(param_set_bint); | |
386 | ||
9c27847d | 387 | const struct kernel_param_ops param_ops_bint = { |
6a4c2643 | 388 | .flags = KERNEL_PARAM_OPS_FL_NOARG, |
69116f27 RR |
389 | .set = param_set_bint, |
390 | .get = param_get_int, | |
391 | }; | |
392 | EXPORT_SYMBOL(param_ops_bint); | |
393 | ||
9730b5b0 | 394 | /* We break the rule and mangle the string. */ |
b51d23e4 DS |
395 | static int param_array(struct module *mod, |
396 | const char *name, | |
9871728b AB |
397 | const char *val, |
398 | unsigned int min, unsigned int max, | |
399 | void *elem, int elemsize, | |
9bbb9e5a | 400 | int (*set)(const char *, const struct kernel_param *kp), |
026cee00 | 401 | s16 level, |
eb38a996 | 402 | unsigned int *num) |
1da177e4 LT |
403 | { |
404 | int ret; | |
405 | struct kernel_param kp; | |
406 | char save; | |
407 | ||
408 | /* Get the name right for errors. */ | |
409 | kp.name = name; | |
410 | kp.arg = elem; | |
026cee00 | 411 | kp.level = level; |
1da177e4 | 412 | |
1da177e4 LT |
413 | *num = 0; |
414 | /* We expect a comma-separated list of values. */ | |
415 | do { | |
416 | int len; | |
417 | ||
418 | if (*num == max) { | |
b5f3abf9 | 419 | pr_err("%s: can only take %i arguments\n", name, max); |
1da177e4 LT |
420 | return -EINVAL; |
421 | } | |
422 | len = strcspn(val, ","); | |
423 | ||
424 | /* nul-terminate and parse */ | |
425 | save = val[len]; | |
426 | ((char *)val)[len] = '\0'; | |
cf2fde7b | 427 | check_kparam_locked(mod); |
1da177e4 LT |
428 | ret = set(val, &kp); |
429 | ||
430 | if (ret != 0) | |
431 | return ret; | |
432 | kp.arg += elemsize; | |
433 | val += len+1; | |
434 | (*num)++; | |
435 | } while (save == ','); | |
436 | ||
437 | if (*num < min) { | |
b5f3abf9 | 438 | pr_err("%s: needs at least %i arguments\n", name, min); |
1da177e4 LT |
439 | return -EINVAL; |
440 | } | |
441 | return 0; | |
442 | } | |
443 | ||
9bbb9e5a | 444 | static int param_array_set(const char *val, const struct kernel_param *kp) |
1da177e4 | 445 | { |
22e48eaf | 446 | const struct kparam_array *arr = kp->arr; |
31143a12 | 447 | unsigned int temp_num; |
1da177e4 | 448 | |
b51d23e4 | 449 | return param_array(kp->mod, kp->name, val, 1, arr->max, arr->elem, |
026cee00 | 450 | arr->elemsize, arr->ops->set, kp->level, |
3c7d76e3 | 451 | arr->num ?: &temp_num); |
1da177e4 LT |
452 | } |
453 | ||
9bbb9e5a | 454 | static int param_array_get(char *buffer, const struct kernel_param *kp) |
1da177e4 LT |
455 | { |
456 | int i, off, ret; | |
22e48eaf | 457 | const struct kparam_array *arr = kp->arr; |
5104b7d7 | 458 | struct kernel_param p = *kp; |
1da177e4 | 459 | |
1da177e4 | 460 | for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) { |
96802e6b | 461 | /* Replace \n with comma */ |
1da177e4 | 462 | if (i) |
96802e6b | 463 | buffer[off - 1] = ','; |
1da177e4 | 464 | p.arg = arr->elem + arr->elemsize * i; |
cf2fde7b | 465 | check_kparam_locked(p.mod); |
9bbb9e5a | 466 | ret = arr->ops->get(buffer + off, &p); |
1da177e4 LT |
467 | if (ret < 0) |
468 | return ret; | |
469 | off += ret; | |
470 | } | |
471 | buffer[off] = '\0'; | |
472 | return off; | |
473 | } | |
474 | ||
e6df34a4 RR |
475 | static void param_array_free(void *arg) |
476 | { | |
477 | unsigned int i; | |
478 | const struct kparam_array *arr = arg; | |
479 | ||
480 | if (arr->ops->free) | |
481 | for (i = 0; i < (arr->num ? *arr->num : arr->max); i++) | |
482 | arr->ops->free(arr->elem + arr->elemsize * i); | |
483 | } | |
484 | ||
9c27847d | 485 | const struct kernel_param_ops param_array_ops = { |
9bbb9e5a RR |
486 | .set = param_array_set, |
487 | .get = param_array_get, | |
e6df34a4 | 488 | .free = param_array_free, |
9bbb9e5a RR |
489 | }; |
490 | EXPORT_SYMBOL(param_array_ops); | |
491 | ||
492 | int param_set_copystring(const char *val, const struct kernel_param *kp) | |
1da177e4 | 493 | { |
22e48eaf | 494 | const struct kparam_string *kps = kp->str; |
1da177e4 LT |
495 | |
496 | if (strlen(val)+1 > kps->maxlen) { | |
b5f3abf9 | 497 | pr_err("%s: string doesn't fit in %u chars.\n", |
1da177e4 LT |
498 | kp->name, kps->maxlen-1); |
499 | return -ENOSPC; | |
500 | } | |
501 | strcpy(kps->string, val); | |
502 | return 0; | |
503 | } | |
a14fe249 | 504 | EXPORT_SYMBOL(param_set_copystring); |
1da177e4 | 505 | |
9bbb9e5a | 506 | int param_get_string(char *buffer, const struct kernel_param *kp) |
1da177e4 | 507 | { |
22e48eaf | 508 | const struct kparam_string *kps = kp->str; |
96802e6b | 509 | return scnprintf(buffer, PAGE_SIZE, "%s\n", kps->string); |
1da177e4 | 510 | } |
a14fe249 | 511 | EXPORT_SYMBOL(param_get_string); |
1da177e4 | 512 | |
9c27847d | 513 | const struct kernel_param_ops param_ops_string = { |
9bbb9e5a RR |
514 | .set = param_set_copystring, |
515 | .get = param_get_string, | |
516 | }; | |
517 | EXPORT_SYMBOL(param_ops_string); | |
518 | ||
1da177e4 | 519 | /* sysfs output in /sys/modules/XYZ/parameters/ */ |
350f8258 EY |
520 | #define to_module_attr(n) container_of(n, struct module_attribute, attr) |
521 | #define to_module_kobject(n) container_of(n, struct module_kobject, kobj) | |
1da177e4 | 522 | |
1da177e4 LT |
523 | struct param_attribute |
524 | { | |
525 | struct module_attribute mattr; | |
9bbb9e5a | 526 | const struct kernel_param *param; |
1da177e4 LT |
527 | }; |
528 | ||
529 | struct module_param_attrs | |
530 | { | |
9b473de8 | 531 | unsigned int num; |
1da177e4 | 532 | struct attribute_group grp; |
fa29c9c1 | 533 | struct param_attribute attrs[]; |
1da177e4 LT |
534 | }; |
535 | ||
ef665c1a | 536 | #ifdef CONFIG_SYSFS |
350f8258 | 537 | #define to_param_attr(n) container_of(n, struct param_attribute, mattr) |
1da177e4 LT |
538 | |
539 | static ssize_t param_attr_show(struct module_attribute *mattr, | |
4befb026 | 540 | struct module_kobject *mk, char *buf) |
1da177e4 LT |
541 | { |
542 | int count; | |
543 | struct param_attribute *attribute = to_param_attr(mattr); | |
544 | ||
9bbb9e5a | 545 | if (!attribute->param->ops->get) |
1da177e4 LT |
546 | return -EPERM; |
547 | ||
b51d23e4 | 548 | kernel_param_lock(mk->mod); |
9bbb9e5a | 549 | count = attribute->param->ops->get(buf, attribute->param); |
b51d23e4 | 550 | kernel_param_unlock(mk->mod); |
1da177e4 LT |
551 | return count; |
552 | } | |
553 | ||
554 | /* sysfs always hands a nul-terminated string in buf. We rely on that. */ | |
555 | static ssize_t param_attr_store(struct module_attribute *mattr, | |
b51d23e4 | 556 | struct module_kobject *mk, |
1da177e4 LT |
557 | const char *buf, size_t len) |
558 | { | |
559 | int err; | |
560 | struct param_attribute *attribute = to_param_attr(mattr); | |
561 | ||
9bbb9e5a | 562 | if (!attribute->param->ops->set) |
1da177e4 LT |
563 | return -EPERM; |
564 | ||
b51d23e4 | 565 | kernel_param_lock(mk->mod); |
20657f66 DH |
566 | if (param_check_unsafe(attribute->param)) |
567 | err = attribute->param->ops->set(buf, attribute->param); | |
568 | else | |
569 | err = -EPERM; | |
b51d23e4 | 570 | kernel_param_unlock(mk->mod); |
1da177e4 LT |
571 | if (!err) |
572 | return len; | |
573 | return err; | |
574 | } | |
ef665c1a | 575 | #endif |
1da177e4 LT |
576 | |
577 | #ifdef CONFIG_MODULES | |
578 | #define __modinit | |
579 | #else | |
580 | #define __modinit __init | |
581 | #endif | |
582 | ||
ef665c1a | 583 | #ifdef CONFIG_SYSFS |
b51d23e4 | 584 | void kernel_param_lock(struct module *mod) |
907b29eb | 585 | { |
b51d23e4 | 586 | mutex_lock(KPARAM_MUTEX(mod)); |
907b29eb | 587 | } |
907b29eb | 588 | |
b51d23e4 | 589 | void kernel_param_unlock(struct module *mod) |
907b29eb | 590 | { |
b51d23e4 | 591 | mutex_unlock(KPARAM_MUTEX(mod)); |
907b29eb | 592 | } |
b51d23e4 | 593 | |
b51d23e4 DS |
594 | EXPORT_SYMBOL(kernel_param_lock); |
595 | EXPORT_SYMBOL(kernel_param_unlock); | |
907b29eb | 596 | |
1da177e4 | 597 | /* |
9b473de8 RR |
598 | * add_sysfs_param - add a parameter to sysfs |
599 | * @mk: struct module_kobject | |
630cc2b3 | 600 | * @kp: the actual parameter definition to add to sysfs |
9b473de8 | 601 | * @name: name of parameter |
1da177e4 | 602 | * |
9b473de8 RR |
603 | * Create a kobject if for a (per-module) parameter if mp NULL, and |
604 | * create file in sysfs. Returns an error on out of memory. Always cleans up | |
605 | * if there's an error. | |
1da177e4 | 606 | */ |
9b473de8 | 607 | static __modinit int add_sysfs_param(struct module_kobject *mk, |
9bbb9e5a | 608 | const struct kernel_param *kp, |
9b473de8 | 609 | const char *name) |
1da177e4 | 610 | { |
18eb74fa RR |
611 | struct module_param_attrs *new_mp; |
612 | struct attribute **new_attrs; | |
613 | unsigned int i; | |
9b473de8 RR |
614 | |
615 | /* We don't bother calling this with invisible parameters. */ | |
616 | BUG_ON(!kp->perm); | |
617 | ||
618 | if (!mk->mp) { | |
18eb74fa RR |
619 | /* First allocation. */ |
620 | mk->mp = kzalloc(sizeof(*mk->mp), GFP_KERNEL); | |
621 | if (!mk->mp) | |
622 | return -ENOMEM; | |
623 | mk->mp->grp.name = "parameters"; | |
624 | /* NULL-terminated attribute array. */ | |
625 | mk->mp->grp.attrs = kzalloc(sizeof(mk->mp->grp.attrs[0]), | |
626 | GFP_KERNEL); | |
627 | /* Caller will cleanup via free_module_param_attrs */ | |
628 | if (!mk->mp->grp.attrs) | |
629 | return -ENOMEM; | |
9b473de8 | 630 | } |
1da177e4 | 631 | |
18eb74fa RR |
632 | /* Enlarge allocations. */ |
633 | new_mp = krealloc(mk->mp, | |
634 | sizeof(*mk->mp) + | |
635 | sizeof(mk->mp->attrs[0]) * (mk->mp->num + 1), | |
636 | GFP_KERNEL); | |
637 | if (!new_mp) | |
638 | return -ENOMEM; | |
639 | mk->mp = new_mp; | |
640 | ||
641 | /* Extra pointer for NULL terminator */ | |
642 | new_attrs = krealloc(mk->mp->grp.attrs, | |
643 | sizeof(mk->mp->grp.attrs[0]) * (mk->mp->num + 2), | |
644 | GFP_KERNEL); | |
645 | if (!new_attrs) | |
646 | return -ENOMEM; | |
647 | mk->mp->grp.attrs = new_attrs; | |
9b473de8 RR |
648 | |
649 | /* Tack new one on the end. */ | |
c772be52 | 650 | memset(&mk->mp->attrs[mk->mp->num], 0, sizeof(mk->mp->attrs[0])); |
18eb74fa RR |
651 | sysfs_attr_init(&mk->mp->attrs[mk->mp->num].mattr.attr); |
652 | mk->mp->attrs[mk->mp->num].param = kp; | |
653 | mk->mp->attrs[mk->mp->num].mattr.show = param_attr_show; | |
b0a65b0c KC |
654 | /* Do not allow runtime DAC changes to make param writable. */ |
655 | if ((kp->perm & (S_IWUSR | S_IWGRP | S_IWOTH)) != 0) | |
656 | mk->mp->attrs[mk->mp->num].mattr.store = param_attr_store; | |
574732c7 RR |
657 | else |
658 | mk->mp->attrs[mk->mp->num].mattr.store = NULL; | |
18eb74fa RR |
659 | mk->mp->attrs[mk->mp->num].mattr.attr.name = (char *)name; |
660 | mk->mp->attrs[mk->mp->num].mattr.attr.mode = kp->perm; | |
661 | mk->mp->num++; | |
9b473de8 RR |
662 | |
663 | /* Fix up all the pointers, since krealloc can move us */ | |
18eb74fa RR |
664 | for (i = 0; i < mk->mp->num; i++) |
665 | mk->mp->grp.attrs[i] = &mk->mp->attrs[i].mattr.attr; | |
666 | mk->mp->grp.attrs[mk->mp->num] = NULL; | |
9b473de8 | 667 | return 0; |
9b473de8 | 668 | } |
1da177e4 | 669 | |
d2441183 | 670 | #ifdef CONFIG_MODULES |
9b473de8 RR |
671 | static void free_module_param_attrs(struct module_kobject *mk) |
672 | { | |
18eb74fa RR |
673 | if (mk->mp) |
674 | kfree(mk->mp->grp.attrs); | |
9b473de8 RR |
675 | kfree(mk->mp); |
676 | mk->mp = NULL; | |
1da177e4 LT |
677 | } |
678 | ||
1da177e4 LT |
679 | /* |
680 | * module_param_sysfs_setup - setup sysfs support for one module | |
681 | * @mod: module | |
682 | * @kparam: module parameters (array) | |
683 | * @num_params: number of module parameters | |
684 | * | |
9b473de8 RR |
685 | * Adds sysfs entries for module parameters under |
686 | * /sys/module/[mod->name]/parameters/ | |
1da177e4 LT |
687 | */ |
688 | int module_param_sysfs_setup(struct module *mod, | |
9bbb9e5a | 689 | const struct kernel_param *kparam, |
1da177e4 LT |
690 | unsigned int num_params) |
691 | { | |
9b473de8 RR |
692 | int i, err; |
693 | bool params = false; | |
694 | ||
695 | for (i = 0; i < num_params; i++) { | |
696 | if (kparam[i].perm == 0) | |
697 | continue; | |
698 | err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name); | |
18eb74fa RR |
699 | if (err) { |
700 | free_module_param_attrs(&mod->mkobj); | |
9b473de8 | 701 | return err; |
18eb74fa | 702 | } |
9b473de8 RR |
703 | params = true; |
704 | } | |
1da177e4 | 705 | |
9b473de8 RR |
706 | if (!params) |
707 | return 0; | |
1da177e4 | 708 | |
9b473de8 RR |
709 | /* Create the param group. */ |
710 | err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
711 | if (err) | |
712 | free_module_param_attrs(&mod->mkobj); | |
713 | return err; | |
1da177e4 LT |
714 | } |
715 | ||
716 | /* | |
717 | * module_param_sysfs_remove - remove sysfs support for one module | |
718 | * @mod: module | |
719 | * | |
720 | * Remove sysfs entries for module parameters and the corresponding | |
721 | * kobject. | |
722 | */ | |
723 | void module_param_sysfs_remove(struct module *mod) | |
724 | { | |
9b473de8 RR |
725 | if (mod->mkobj.mp) { |
726 | sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp); | |
1da177e4 LT |
727 | /* We are positive that no one is using any param |
728 | * attrs at this point. Deallocate immediately. */ | |
9b473de8 | 729 | free_module_param_attrs(&mod->mkobj); |
1da177e4 LT |
730 | } |
731 | } | |
732 | #endif | |
733 | ||
e180a6b7 RR |
734 | void destroy_params(const struct kernel_param *params, unsigned num) |
735 | { | |
e6df34a4 RR |
736 | unsigned int i; |
737 | ||
738 | for (i = 0; i < num; i++) | |
739 | if (params[i].ops->free) | |
740 | params[i].ops->free(params[i].arg); | |
e180a6b7 RR |
741 | } |
742 | ||
e94965ed | 743 | static struct module_kobject * __init locate_module_kobject(const char *name) |
1da177e4 LT |
744 | { |
745 | struct module_kobject *mk; | |
9b473de8 RR |
746 | struct kobject *kobj; |
747 | int err; | |
1da177e4 | 748 | |
9b473de8 RR |
749 | kobj = kset_find_obj(module_kset, name); |
750 | if (kobj) { | |
9b473de8 | 751 | mk = to_module_kobject(kobj); |
9b473de8 RR |
752 | } else { |
753 | mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL); | |
754 | BUG_ON(!mk); | |
755 | ||
756 | mk->mod = THIS_MODULE; | |
757 | mk->kobj.kset = module_kset; | |
758 | err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL, | |
759 | "%s", name); | |
88bfa324 KS |
760 | #ifdef CONFIG_MODULES |
761 | if (!err) | |
762 | err = sysfs_create_file(&mk->kobj, &module_uevent.attr); | |
763 | #endif | |
9b473de8 RR |
764 | if (err) { |
765 | kobject_put(&mk->kobj); | |
b5f3abf9 | 766 | pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n", |
e94965ed | 767 | name, err); |
e94965ed | 768 | return NULL; |
9b473de8 | 769 | } |
e94965ed DT |
770 | |
771 | /* So that we hold reference in both cases. */ | |
9b473de8 | 772 | kobject_get(&mk->kobj); |
74c5b597 | 773 | } |
9b473de8 | 774 | |
e94965ed DT |
775 | return mk; |
776 | } | |
777 | ||
778 | static void __init kernel_add_sysfs_param(const char *name, | |
63a12d9d | 779 | const struct kernel_param *kparam, |
e94965ed DT |
780 | unsigned int name_skip) |
781 | { | |
782 | struct module_kobject *mk; | |
783 | int err; | |
784 | ||
785 | mk = locate_module_kobject(name); | |
786 | if (!mk) | |
787 | return; | |
788 | ||
789 | /* We need to remove old parameters before adding more. */ | |
790 | if (mk->mp) | |
791 | sysfs_remove_group(&mk->kobj, &mk->mp->grp); | |
792 | ||
9b473de8 RR |
793 | /* These should not fail at boot. */ |
794 | err = add_sysfs_param(mk, kparam, kparam->name + name_skip); | |
795 | BUG_ON(err); | |
796 | err = sysfs_create_group(&mk->kobj, &mk->mp->grp); | |
797 | BUG_ON(err); | |
f30c53a8 | 798 | kobject_uevent(&mk->kobj, KOBJ_ADD); |
9b473de8 | 799 | kobject_put(&mk->kobj); |
1da177e4 LT |
800 | } |
801 | ||
802 | /* | |
b634d130 | 803 | * param_sysfs_builtin - add sysfs parameters for built-in modules |
1da177e4 LT |
804 | * |
805 | * Add module_parameters to sysfs for "modules" built into the kernel. | |
806 | * | |
807 | * The "module" name (KBUILD_MODNAME) is stored before a dot, the | |
808 | * "parameter" name is stored behind a dot in kernel_param->name. So, | |
809 | * extract the "module" name for all built-in kernel_param-eters, | |
9b473de8 | 810 | * and for all who have the same, call kernel_add_sysfs_param. |
1da177e4 LT |
811 | */ |
812 | static void __init param_sysfs_builtin(void) | |
813 | { | |
63a12d9d | 814 | const struct kernel_param *kp; |
9b473de8 RR |
815 | unsigned int name_len; |
816 | char modname[MODULE_NAME_LEN]; | |
1da177e4 | 817 | |
9b473de8 | 818 | for (kp = __start___param; kp < __stop___param; kp++) { |
1da177e4 LT |
819 | char *dot; |
820 | ||
9b473de8 RR |
821 | if (kp->perm == 0) |
822 | continue; | |
1da177e4 | 823 | |
730b69d2 | 824 | dot = strchr(kp->name, '.'); |
1da177e4 | 825 | if (!dot) { |
67e67cea RR |
826 | /* This happens for core_param() */ |
827 | strcpy(modname, "kernel"); | |
828 | name_len = 0; | |
829 | } else { | |
830 | name_len = dot - kp->name + 1; | |
831 | strlcpy(modname, kp->name, name_len); | |
1da177e4 | 832 | } |
67e67cea | 833 | kernel_add_sysfs_param(modname, kp, name_len); |
1da177e4 | 834 | } |
1da177e4 LT |
835 | } |
836 | ||
e94965ed | 837 | ssize_t __modver_version_show(struct module_attribute *mattr, |
4befb026 | 838 | struct module_kobject *mk, char *buf) |
e94965ed DT |
839 | { |
840 | struct module_version_attribute *vattr = | |
841 | container_of(mattr, struct module_version_attribute, mattr); | |
842 | ||
f4940ab7 | 843 | return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version); |
e94965ed DT |
844 | } |
845 | ||
b112082c JH |
846 | extern const struct module_version_attribute __start___modver[]; |
847 | extern const struct module_version_attribute __stop___modver[]; | |
e94965ed DT |
848 | |
849 | static void __init version_sysfs_builtin(void) | |
850 | { | |
b112082c | 851 | const struct module_version_attribute *vattr; |
e94965ed DT |
852 | struct module_kobject *mk; |
853 | int err; | |
854 | ||
b112082c | 855 | for (vattr = __start___modver; vattr < __stop___modver; vattr++) { |
e94965ed DT |
856 | mk = locate_module_kobject(vattr->module_name); |
857 | if (mk) { | |
858 | err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr); | |
74c3dea3 | 859 | WARN_ON_ONCE(err); |
e94965ed DT |
860 | kobject_uevent(&mk->kobj, KOBJ_ADD); |
861 | kobject_put(&mk->kobj); | |
862 | } | |
863 | } | |
864 | } | |
1da177e4 LT |
865 | |
866 | /* module-related sysfs stuff */ | |
1da177e4 | 867 | |
1da177e4 LT |
868 | static ssize_t module_attr_show(struct kobject *kobj, |
869 | struct attribute *attr, | |
870 | char *buf) | |
871 | { | |
872 | struct module_attribute *attribute; | |
873 | struct module_kobject *mk; | |
874 | int ret; | |
875 | ||
876 | attribute = to_module_attr(attr); | |
877 | mk = to_module_kobject(kobj); | |
878 | ||
879 | if (!attribute->show) | |
70f2817a | 880 | return -EIO; |
1da177e4 | 881 | |
4befb026 | 882 | ret = attribute->show(attribute, mk, buf); |
1da177e4 | 883 | |
1da177e4 LT |
884 | return ret; |
885 | } | |
886 | ||
887 | static ssize_t module_attr_store(struct kobject *kobj, | |
888 | struct attribute *attr, | |
889 | const char *buf, size_t len) | |
890 | { | |
891 | struct module_attribute *attribute; | |
892 | struct module_kobject *mk; | |
893 | int ret; | |
894 | ||
895 | attribute = to_module_attr(attr); | |
896 | mk = to_module_kobject(kobj); | |
897 | ||
898 | if (!attribute->store) | |
70f2817a | 899 | return -EIO; |
1da177e4 | 900 | |
4befb026 | 901 | ret = attribute->store(attribute, mk, buf, len); |
1da177e4 | 902 | |
1da177e4 LT |
903 | return ret; |
904 | } | |
905 | ||
52cf25d0 | 906 | static const struct sysfs_ops module_sysfs_ops = { |
1da177e4 LT |
907 | .show = module_attr_show, |
908 | .store = module_attr_store, | |
909 | }; | |
910 | ||
270a6c4c KS |
911 | static int uevent_filter(struct kset *kset, struct kobject *kobj) |
912 | { | |
913 | struct kobj_type *ktype = get_ktype(kobj); | |
914 | ||
915 | if (ktype == &module_ktype) | |
916 | return 1; | |
917 | return 0; | |
918 | } | |
919 | ||
9cd43611 | 920 | static const struct kset_uevent_ops module_uevent_ops = { |
270a6c4c KS |
921 | .filter = uevent_filter, |
922 | }; | |
923 | ||
7405c1e1 | 924 | struct kset *module_kset; |
823bccfc | 925 | int module_sysfs_initialized; |
1da177e4 | 926 | |
942e4431 LZ |
927 | static void module_kobj_release(struct kobject *kobj) |
928 | { | |
929 | struct module_kobject *mk = to_module_kobject(kobj); | |
930 | complete(mk->kobj_completion); | |
931 | } | |
932 | ||
7405c1e1 | 933 | struct kobj_type module_ktype = { |
942e4431 | 934 | .release = module_kobj_release, |
1da177e4 LT |
935 | .sysfs_ops = &module_sysfs_ops, |
936 | }; | |
937 | ||
1da177e4 LT |
938 | /* |
939 | * param_sysfs_init - wrapper for built-in params support | |
940 | */ | |
941 | static int __init param_sysfs_init(void) | |
942 | { | |
7405c1e1 GKH |
943 | module_kset = kset_create_and_add("module", &module_uevent_ops, NULL); |
944 | if (!module_kset) { | |
945 | printk(KERN_WARNING "%s (%d): error creating kset\n", | |
946 | __FILE__, __LINE__); | |
947 | return -ENOMEM; | |
d8c7649e | 948 | } |
823bccfc | 949 | module_sysfs_initialized = 1; |
1da177e4 | 950 | |
e94965ed | 951 | version_sysfs_builtin(); |
1da177e4 LT |
952 | param_sysfs_builtin(); |
953 | ||
954 | return 0; | |
955 | } | |
d10be6d1 | 956 | subsys_initcall(param_sysfs_init); |
1da177e4 | 957 | |
7405c1e1 | 958 | #endif /* CONFIG_SYSFS */ |