params.c 21 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/moduleparam.h>
  16. #include <linux/kernel.h>
  17. #include <linux/string.h>
  18. #include <linux/errno.h>
  19. #include <linux/module.h>
  20. #include <linux/device.h>
  21. #include <linux/err.h>
  22. #include <linux/slab.h>
  23. #include <linux/ctype.h>
  24. #if 0
  25. #define DEBUGP printk
  26. #else
  27. #define DEBUGP(fmt, a...)
  28. #endif
  29. /* Protects all parameters, and incidentally kmalloced_param list. */
  30. static DEFINE_MUTEX(param_lock);
  31. /* This just allows us to keep track of which parameters are kmalloced. */
  32. struct kmalloced_param {
  33. struct list_head list;
  34. char val[];
  35. };
  36. static LIST_HEAD(kmalloced_params);
  37. static void *kmalloc_parameter(unsigned int size)
  38. {
  39. struct kmalloced_param *p;
  40. p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
  41. if (!p)
  42. return NULL;
  43. list_add(&p->list, &kmalloced_params);
  44. return p->val;
  45. }
  46. /* Does nothing if parameter wasn't kmalloced above. */
  47. static void maybe_kfree_parameter(void *param)
  48. {
  49. struct kmalloced_param *p;
  50. list_for_each_entry(p, &kmalloced_params, list) {
  51. if (p->val == param) {
  52. list_del(&p->list);
  53. kfree(p);
  54. break;
  55. }
  56. }
  57. }
  58. static inline char dash2underscore(char c)
  59. {
  60. if (c == '-')
  61. return '_';
  62. return c;
  63. }
  64. static inline int parameq(const char *input, const char *paramname)
  65. {
  66. unsigned int i;
  67. for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
  68. if (input[i] == '\0')
  69. return 1;
  70. return 0;
  71. }
  72. static int parse_one(char *param,
  73. char *val,
  74. const struct kernel_param *params,
  75. unsigned num_params,
  76. int (*handle_unknown)(char *param, char *val))
  77. {
  78. unsigned int i;
  79. int err;
  80. /* Find parameter */
  81. for (i = 0; i < num_params; i++) {
  82. if (parameq(param, params[i].name)) {
  83. /* No one handled NULL, so do it here. */
  84. if (!val && params[i].ops->set != param_set_bool)
  85. return -EINVAL;
  86. DEBUGP("They are equal! Calling %p\n",
  87. params[i].ops->set);
  88. mutex_lock(&param_lock);
  89. err = params[i].ops->set(val, &params[i]);
  90. mutex_unlock(&param_lock);
  91. return err;
  92. }
  93. }
  94. if (handle_unknown) {
  95. DEBUGP("Unknown argument: calling %p\n", handle_unknown);
  96. return handle_unknown(param, val);
  97. }
  98. DEBUGP("Unknown argument `%s'\n", param);
  99. return -ENOENT;
  100. }
  101. /* You can use " around spaces, but can't escape ". */
  102. /* Hyphens and underscores equivalent in parameter names. */
  103. static char *next_arg(char *args, char **param, char **val)
  104. {
  105. unsigned int i, equals = 0;
  106. int in_quote = 0, quoted = 0;
  107. char *next;
  108. if (*args == '"') {
  109. args++;
  110. in_quote = 1;
  111. quoted = 1;
  112. }
  113. for (i = 0; args[i]; i++) {
  114. if (isspace(args[i]) && !in_quote)
  115. break;
  116. if (equals == 0) {
  117. if (args[i] == '=')
  118. equals = i;
  119. }
  120. if (args[i] == '"')
  121. in_quote = !in_quote;
  122. }
  123. *param = args;
  124. if (!equals)
  125. *val = NULL;
  126. else {
  127. args[equals] = '\0';
  128. *val = args + equals + 1;
  129. /* Don't include quotes in value. */
  130. if (**val == '"') {
  131. (*val)++;
  132. if (args[i-1] == '"')
  133. args[i-1] = '\0';
  134. }
  135. if (quoted && args[i-1] == '"')
  136. args[i-1] = '\0';
  137. }
  138. if (args[i]) {
  139. args[i] = '\0';
  140. next = args + i + 1;
  141. } else
  142. next = args + i;
  143. /* Chew up trailing spaces. */
  144. return skip_spaces(next);
  145. }
  146. /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
  147. int parse_args(const char *name,
  148. char *args,
  149. const struct kernel_param *params,
  150. unsigned num,
  151. int (*unknown)(char *param, char *val))
  152. {
  153. char *param, *val;
  154. DEBUGP("Parsing ARGS: %s\n", args);
  155. /* Chew leading spaces */
  156. args = skip_spaces(args);
  157. while (*args) {
  158. int ret;
  159. int irq_was_disabled;
  160. args = next_arg(args, &param, &val);
  161. irq_was_disabled = irqs_disabled();
  162. ret = parse_one(param, val, params, num, unknown);
  163. if (irq_was_disabled && !irqs_disabled()) {
  164. printk(KERN_WARNING "parse_args(): option '%s' enabled "
  165. "irq's!\n", param);
  166. }
  167. switch (ret) {
  168. case -ENOENT:
  169. printk(KERN_ERR "%s: Unknown parameter `%s'\n",
  170. name, param);
  171. return ret;
  172. case -ENOSPC:
  173. printk(KERN_ERR
  174. "%s: `%s' too large for parameter `%s'\n",
  175. name, val ?: "", param);
  176. return ret;
  177. case 0:
  178. break;
  179. default:
  180. printk(KERN_ERR
  181. "%s: `%s' invalid for parameter `%s'\n",
  182. name, val ?: "", param);
  183. return ret;
  184. }
  185. }
  186. /* All parsed OK. */
  187. return 0;
  188. }
  189. /* Lazy bastard, eh? */
  190. #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
  191. int param_set_##name(const char *val, const struct kernel_param *kp) \
  192. { \
  193. tmptype l; \
  194. int ret; \
  195. \
  196. ret = strtolfn(val, 0, &l); \
  197. if (ret == -EINVAL || ((type)l != l)) \
  198. return -EINVAL; \
  199. *((type *)kp->arg) = l; \
  200. return 0; \
  201. } \
  202. int param_get_##name(char *buffer, const struct kernel_param *kp) \
  203. { \
  204. return sprintf(buffer, format, *((type *)kp->arg)); \
  205. } \
  206. struct kernel_param_ops param_ops_##name = { \
  207. .set = param_set_##name, \
  208. .get = param_get_##name, \
  209. }; \
  210. EXPORT_SYMBOL(param_set_##name); \
  211. EXPORT_SYMBOL(param_get_##name); \
  212. EXPORT_SYMBOL(param_ops_##name)
  213. STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
  214. STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
  215. STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
  216. STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
  217. STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
  218. STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
  219. STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
  220. int param_set_charp(const char *val, const struct kernel_param *kp)
  221. {
  222. if (strlen(val) > 1024) {
  223. printk(KERN_ERR "%s: string parameter too long\n",
  224. kp->name);
  225. return -ENOSPC;
  226. }
  227. maybe_kfree_parameter(*(char **)kp->arg);
  228. /* This is a hack. We can't kmalloc in early boot, and we
  229. * don't need to; this mangled commandline is preserved. */
  230. if (slab_is_available()) {
  231. *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
  232. if (!*(char **)kp->arg)
  233. return -ENOMEM;
  234. strcpy(*(char **)kp->arg, val);
  235. } else
  236. *(const char **)kp->arg = val;
  237. return 0;
  238. }
  239. EXPORT_SYMBOL(param_set_charp);
  240. int param_get_charp(char *buffer, const struct kernel_param *kp)
  241. {
  242. return sprintf(buffer, "%s", *((char **)kp->arg));
  243. }
  244. EXPORT_SYMBOL(param_get_charp);
  245. static void param_free_charp(void *arg)
  246. {
  247. maybe_kfree_parameter(*((char **)arg));
  248. }
  249. struct kernel_param_ops param_ops_charp = {
  250. .set = param_set_charp,
  251. .get = param_get_charp,
  252. .free = param_free_charp,
  253. };
  254. EXPORT_SYMBOL(param_ops_charp);
  255. /* Actually could be a bool or an int, for historical reasons. */
  256. int param_set_bool(const char *val, const struct kernel_param *kp)
  257. {
  258. bool v;
  259. int ret;
  260. /* No equals means "set"... */
  261. if (!val) val = "1";
  262. /* One of =[yYnN01] */
  263. ret = strtobool(val, &v);
  264. if (ret)
  265. return ret;
  266. if (kp->flags & KPARAM_ISBOOL)
  267. *(bool *)kp->arg = v;
  268. else
  269. *(int *)kp->arg = v;
  270. return 0;
  271. }
  272. EXPORT_SYMBOL(param_set_bool);
  273. int param_get_bool(char *buffer, const struct kernel_param *kp)
  274. {
  275. bool val;
  276. if (kp->flags & KPARAM_ISBOOL)
  277. val = *(bool *)kp->arg;
  278. else
  279. val = *(int *)kp->arg;
  280. /* Y and N chosen as being relatively non-coder friendly */
  281. return sprintf(buffer, "%c", val ? 'Y' : 'N');
  282. }
  283. EXPORT_SYMBOL(param_get_bool);
  284. struct kernel_param_ops param_ops_bool = {
  285. .set = param_set_bool,
  286. .get = param_get_bool,
  287. };
  288. EXPORT_SYMBOL(param_ops_bool);
  289. /* This one must be bool. */
  290. int param_set_invbool(const char *val, const struct kernel_param *kp)
  291. {
  292. int ret;
  293. bool boolval;
  294. struct kernel_param dummy;
  295. dummy.arg = &boolval;
  296. dummy.flags = KPARAM_ISBOOL;
  297. ret = param_set_bool(val, &dummy);
  298. if (ret == 0)
  299. *(bool *)kp->arg = !boolval;
  300. return ret;
  301. }
  302. EXPORT_SYMBOL(param_set_invbool);
  303. int param_get_invbool(char *buffer, const struct kernel_param *kp)
  304. {
  305. return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
  306. }
  307. EXPORT_SYMBOL(param_get_invbool);
  308. struct kernel_param_ops param_ops_invbool = {
  309. .set = param_set_invbool,
  310. .get = param_get_invbool,
  311. };
  312. EXPORT_SYMBOL(param_ops_invbool);
  313. /* We break the rule and mangle the string. */
  314. static int param_array(const char *name,
  315. const char *val,
  316. unsigned int min, unsigned int max,
  317. void *elem, int elemsize,
  318. int (*set)(const char *, const struct kernel_param *kp),
  319. u16 flags,
  320. unsigned int *num)
  321. {
  322. int ret;
  323. struct kernel_param kp;
  324. char save;
  325. /* Get the name right for errors. */
  326. kp.name = name;
  327. kp.arg = elem;
  328. kp.flags = flags;
  329. *num = 0;
  330. /* We expect a comma-separated list of values. */
  331. do {
  332. int len;
  333. if (*num == max) {
  334. printk(KERN_ERR "%s: can only take %i arguments\n",
  335. name, max);
  336. return -EINVAL;
  337. }
  338. len = strcspn(val, ",");
  339. /* nul-terminate and parse */
  340. save = val[len];
  341. ((char *)val)[len] = '\0';
  342. BUG_ON(!mutex_is_locked(&param_lock));
  343. ret = set(val, &kp);
  344. if (ret != 0)
  345. return ret;
  346. kp.arg += elemsize;
  347. val += len+1;
  348. (*num)++;
  349. } while (save == ',');
  350. if (*num < min) {
  351. printk(KERN_ERR "%s: needs at least %i arguments\n",
  352. name, min);
  353. return -EINVAL;
  354. }
  355. return 0;
  356. }
  357. static int param_array_set(const char *val, const struct kernel_param *kp)
  358. {
  359. const struct kparam_array *arr = kp->arr;
  360. unsigned int temp_num;
  361. return param_array(kp->name, val, 1, arr->max, arr->elem,
  362. arr->elemsize, arr->ops->set, kp->flags,
  363. arr->num ?: &temp_num);
  364. }
  365. static int param_array_get(char *buffer, const struct kernel_param *kp)
  366. {
  367. int i, off, ret;
  368. const struct kparam_array *arr = kp->arr;
  369. struct kernel_param p;
  370. p = *kp;
  371. for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
  372. if (i)
  373. buffer[off++] = ',';
  374. p.arg = arr->elem + arr->elemsize * i;
  375. BUG_ON(!mutex_is_locked(&param_lock));
  376. ret = arr->ops->get(buffer + off, &p);
  377. if (ret < 0)
  378. return ret;
  379. off += ret;
  380. }
  381. buffer[off] = '\0';
  382. return off;
  383. }
  384. static void param_array_free(void *arg)
  385. {
  386. unsigned int i;
  387. const struct kparam_array *arr = arg;
  388. if (arr->ops->free)
  389. for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
  390. arr->ops->free(arr->elem + arr->elemsize * i);
  391. }
  392. struct kernel_param_ops param_array_ops = {
  393. .set = param_array_set,
  394. .get = param_array_get,
  395. .free = param_array_free,
  396. };
  397. EXPORT_SYMBOL(param_array_ops);
  398. int param_set_copystring(const char *val, const struct kernel_param *kp)
  399. {
  400. const struct kparam_string *kps = kp->str;
  401. if (strlen(val)+1 > kps->maxlen) {
  402. printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
  403. kp->name, kps->maxlen-1);
  404. return -ENOSPC;
  405. }
  406. strcpy(kps->string, val);
  407. return 0;
  408. }
  409. EXPORT_SYMBOL(param_set_copystring);
  410. int param_get_string(char *buffer, const struct kernel_param *kp)
  411. {
  412. const struct kparam_string *kps = kp->str;
  413. return strlcpy(buffer, kps->string, kps->maxlen);
  414. }
  415. EXPORT_SYMBOL(param_get_string);
  416. struct kernel_param_ops param_ops_string = {
  417. .set = param_set_copystring,
  418. .get = param_get_string,
  419. };
  420. EXPORT_SYMBOL(param_ops_string);
  421. /* sysfs output in /sys/modules/XYZ/parameters/ */
  422. #define to_module_attr(n) container_of(n, struct module_attribute, attr)
  423. #define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
  424. extern struct kernel_param __start___param[], __stop___param[];
  425. struct param_attribute
  426. {
  427. struct module_attribute mattr;
  428. const struct kernel_param *param;
  429. };
  430. struct module_param_attrs
  431. {
  432. unsigned int num;
  433. struct attribute_group grp;
  434. struct param_attribute attrs[0];
  435. };
  436. #ifdef CONFIG_SYSFS
  437. #define to_param_attr(n) container_of(n, struct param_attribute, mattr)
  438. static ssize_t param_attr_show(struct module_attribute *mattr,
  439. struct module *mod, char *buf)
  440. {
  441. int count;
  442. struct param_attribute *attribute = to_param_attr(mattr);
  443. if (!attribute->param->ops->get)
  444. return -EPERM;
  445. mutex_lock(&param_lock);
  446. count = attribute->param->ops->get(buf, attribute->param);
  447. mutex_unlock(&param_lock);
  448. if (count > 0) {
  449. strcat(buf, "\n");
  450. ++count;
  451. }
  452. return count;
  453. }
  454. /* sysfs always hands a nul-terminated string in buf. We rely on that. */
  455. static ssize_t param_attr_store(struct module_attribute *mattr,
  456. struct module *owner,
  457. const char *buf, size_t len)
  458. {
  459. int err;
  460. struct param_attribute *attribute = to_param_attr(mattr);
  461. if (!attribute->param->ops->set)
  462. return -EPERM;
  463. mutex_lock(&param_lock);
  464. err = attribute->param->ops->set(buf, attribute->param);
  465. mutex_unlock(&param_lock);
  466. if (!err)
  467. return len;
  468. return err;
  469. }
  470. #endif
  471. #ifdef CONFIG_MODULES
  472. #define __modinit
  473. #else
  474. #define __modinit __init
  475. #endif
  476. #ifdef CONFIG_SYSFS
  477. void __kernel_param_lock(void)
  478. {
  479. mutex_lock(&param_lock);
  480. }
  481. EXPORT_SYMBOL(__kernel_param_lock);
  482. void __kernel_param_unlock(void)
  483. {
  484. mutex_unlock(&param_lock);
  485. }
  486. EXPORT_SYMBOL(__kernel_param_unlock);
  487. /*
  488. * add_sysfs_param - add a parameter to sysfs
  489. * @mk: struct module_kobject
  490. * @kparam: the actual parameter definition to add to sysfs
  491. * @name: name of parameter
  492. *
  493. * Create a kobject if for a (per-module) parameter if mp NULL, and
  494. * create file in sysfs. Returns an error on out of memory. Always cleans up
  495. * if there's an error.
  496. */
  497. static __modinit int add_sysfs_param(struct module_kobject *mk,
  498. const struct kernel_param *kp,
  499. const char *name)
  500. {
  501. struct module_param_attrs *new;
  502. struct attribute **attrs;
  503. int err, num;
  504. /* We don't bother calling this with invisible parameters. */
  505. BUG_ON(!kp->perm);
  506. if (!mk->mp) {
  507. num = 0;
  508. attrs = NULL;
  509. } else {
  510. num = mk->mp->num;
  511. attrs = mk->mp->grp.attrs;
  512. }
  513. /* Enlarge. */
  514. new = krealloc(mk->mp,
  515. sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
  516. GFP_KERNEL);
  517. if (!new) {
  518. kfree(mk->mp);
  519. err = -ENOMEM;
  520. goto fail;
  521. }
  522. attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
  523. if (!attrs) {
  524. err = -ENOMEM;
  525. goto fail_free_new;
  526. }
  527. /* Sysfs wants everything zeroed. */
  528. memset(new, 0, sizeof(*new));
  529. memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
  530. memset(&attrs[num], 0, sizeof(attrs[num]));
  531. new->grp.name = "parameters";
  532. new->grp.attrs = attrs;
  533. /* Tack new one on the end. */
  534. sysfs_attr_init(&new->attrs[num].mattr.attr);
  535. new->attrs[num].param = kp;
  536. new->attrs[num].mattr.show = param_attr_show;
  537. new->attrs[num].mattr.store = param_attr_store;
  538. new->attrs[num].mattr.attr.name = (char *)name;
  539. new->attrs[num].mattr.attr.mode = kp->perm;
  540. new->num = num+1;
  541. /* Fix up all the pointers, since krealloc can move us */
  542. for (num = 0; num < new->num; num++)
  543. new->grp.attrs[num] = &new->attrs[num].mattr.attr;
  544. new->grp.attrs[num] = NULL;
  545. mk->mp = new;
  546. return 0;
  547. fail_free_new:
  548. kfree(new);
  549. fail:
  550. mk->mp = NULL;
  551. return err;
  552. }
  553. #ifdef CONFIG_MODULES
  554. static void free_module_param_attrs(struct module_kobject *mk)
  555. {
  556. kfree(mk->mp->grp.attrs);
  557. kfree(mk->mp);
  558. mk->mp = NULL;
  559. }
  560. /*
  561. * module_param_sysfs_setup - setup sysfs support for one module
  562. * @mod: module
  563. * @kparam: module parameters (array)
  564. * @num_params: number of module parameters
  565. *
  566. * Adds sysfs entries for module parameters under
  567. * /sys/module/[mod->name]/parameters/
  568. */
  569. int module_param_sysfs_setup(struct module *mod,
  570. const struct kernel_param *kparam,
  571. unsigned int num_params)
  572. {
  573. int i, err;
  574. bool params = false;
  575. for (i = 0; i < num_params; i++) {
  576. if (kparam[i].perm == 0)
  577. continue;
  578. err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
  579. if (err)
  580. return err;
  581. params = true;
  582. }
  583. if (!params)
  584. return 0;
  585. /* Create the param group. */
  586. err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
  587. if (err)
  588. free_module_param_attrs(&mod->mkobj);
  589. return err;
  590. }
  591. /*
  592. * module_param_sysfs_remove - remove sysfs support for one module
  593. * @mod: module
  594. *
  595. * Remove sysfs entries for module parameters and the corresponding
  596. * kobject.
  597. */
  598. void module_param_sysfs_remove(struct module *mod)
  599. {
  600. if (mod->mkobj.mp) {
  601. sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
  602. /* We are positive that no one is using any param
  603. * attrs at this point. Deallocate immediately. */
  604. free_module_param_attrs(&mod->mkobj);
  605. }
  606. }
  607. #endif
  608. void destroy_params(const struct kernel_param *params, unsigned num)
  609. {
  610. unsigned int i;
  611. for (i = 0; i < num; i++)
  612. if (params[i].ops->free)
  613. params[i].ops->free(params[i].arg);
  614. }
  615. static struct module_kobject * __init locate_module_kobject(const char *name)
  616. {
  617. struct module_kobject *mk;
  618. struct kobject *kobj;
  619. int err;
  620. kobj = kset_find_obj(module_kset, name);
  621. if (kobj) {
  622. mk = to_module_kobject(kobj);
  623. } else {
  624. mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
  625. BUG_ON(!mk);
  626. mk->mod = THIS_MODULE;
  627. mk->kobj.kset = module_kset;
  628. err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
  629. "%s", name);
  630. if (err) {
  631. kobject_put(&mk->kobj);
  632. printk(KERN_ERR
  633. "Module '%s' failed add to sysfs, error number %d\n",
  634. name, err);
  635. printk(KERN_ERR
  636. "The system will be unstable now.\n");
  637. return NULL;
  638. }
  639. /* So that we hold reference in both cases. */
  640. kobject_get(&mk->kobj);
  641. }
  642. return mk;
  643. }
  644. static void __init kernel_add_sysfs_param(const char *name,
  645. struct kernel_param *kparam,
  646. unsigned int name_skip)
  647. {
  648. struct module_kobject *mk;
  649. int err;
  650. mk = locate_module_kobject(name);
  651. if (!mk)
  652. return;
  653. /* We need to remove old parameters before adding more. */
  654. if (mk->mp)
  655. sysfs_remove_group(&mk->kobj, &mk->mp->grp);
  656. /* These should not fail at boot. */
  657. err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
  658. BUG_ON(err);
  659. err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
  660. BUG_ON(err);
  661. kobject_uevent(&mk->kobj, KOBJ_ADD);
  662. kobject_put(&mk->kobj);
  663. }
  664. /*
  665. * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
  666. *
  667. * Add module_parameters to sysfs for "modules" built into the kernel.
  668. *
  669. * The "module" name (KBUILD_MODNAME) is stored before a dot, the
  670. * "parameter" name is stored behind a dot in kernel_param->name. So,
  671. * extract the "module" name for all built-in kernel_param-eters,
  672. * and for all who have the same, call kernel_add_sysfs_param.
  673. */
  674. static void __init param_sysfs_builtin(void)
  675. {
  676. struct kernel_param *kp;
  677. unsigned int name_len;
  678. char modname[MODULE_NAME_LEN];
  679. for (kp = __start___param; kp < __stop___param; kp++) {
  680. char *dot;
  681. if (kp->perm == 0)
  682. continue;
  683. dot = strchr(kp->name, '.');
  684. if (!dot) {
  685. /* This happens for core_param() */
  686. strcpy(modname, "kernel");
  687. name_len = 0;
  688. } else {
  689. name_len = dot - kp->name + 1;
  690. strlcpy(modname, kp->name, name_len);
  691. }
  692. kernel_add_sysfs_param(modname, kp, name_len);
  693. }
  694. }
  695. ssize_t __modver_version_show(struct module_attribute *mattr,
  696. struct module *mod, char *buf)
  697. {
  698. struct module_version_attribute *vattr =
  699. container_of(mattr, struct module_version_attribute, mattr);
  700. return sprintf(buf, "%s\n", vattr->version);
  701. }
  702. extern const struct module_version_attribute *__start___modver[];
  703. extern const struct module_version_attribute *__stop___modver[];
  704. static void __init version_sysfs_builtin(void)
  705. {
  706. const struct module_version_attribute **p;
  707. struct module_kobject *mk;
  708. int err;
  709. for (p = __start___modver; p < __stop___modver; p++) {
  710. const struct module_version_attribute *vattr = *p;
  711. mk = locate_module_kobject(vattr->module_name);
  712. if (mk) {
  713. err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
  714. kobject_uevent(&mk->kobj, KOBJ_ADD);
  715. kobject_put(&mk->kobj);
  716. }
  717. }
  718. }
  719. /* module-related sysfs stuff */
  720. static ssize_t module_attr_show(struct kobject *kobj,
  721. struct attribute *attr,
  722. char *buf)
  723. {
  724. struct module_attribute *attribute;
  725. struct module_kobject *mk;
  726. int ret;
  727. attribute = to_module_attr(attr);
  728. mk = to_module_kobject(kobj);
  729. if (!attribute->show)
  730. return -EIO;
  731. ret = attribute->show(attribute, mk->mod, buf);
  732. return ret;
  733. }
  734. static ssize_t module_attr_store(struct kobject *kobj,
  735. struct attribute *attr,
  736. const char *buf, size_t len)
  737. {
  738. struct module_attribute *attribute;
  739. struct module_kobject *mk;
  740. int ret;
  741. attribute = to_module_attr(attr);
  742. mk = to_module_kobject(kobj);
  743. if (!attribute->store)
  744. return -EIO;
  745. ret = attribute->store(attribute, mk->mod, buf, len);
  746. return ret;
  747. }
  748. static const struct sysfs_ops module_sysfs_ops = {
  749. .show = module_attr_show,
  750. .store = module_attr_store,
  751. };
  752. static int uevent_filter(struct kset *kset, struct kobject *kobj)
  753. {
  754. struct kobj_type *ktype = get_ktype(kobj);
  755. if (ktype == &module_ktype)
  756. return 1;
  757. return 0;
  758. }
  759. static const struct kset_uevent_ops module_uevent_ops = {
  760. .filter = uevent_filter,
  761. };
  762. struct kset *module_kset;
  763. int module_sysfs_initialized;
  764. struct kobj_type module_ktype = {
  765. .sysfs_ops = &module_sysfs_ops,
  766. };
  767. /*
  768. * param_sysfs_init - wrapper for built-in params support
  769. */
  770. static int __init param_sysfs_init(void)
  771. {
  772. module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
  773. if (!module_kset) {
  774. printk(KERN_WARNING "%s (%d): error creating kset\n",
  775. __FILE__, __LINE__);
  776. return -ENOMEM;
  777. }
  778. module_sysfs_initialized = 1;
  779. version_sysfs_builtin();
  780. param_sysfs_builtin();
  781. return 0;
  782. }
  783. subsys_initcall(param_sysfs_init);
  784. #endif /* CONFIG_SYSFS */