params.c 22 KB

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