projects/linux·blob v4.1-rc3 · refs

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1/* Helpers for initial module or kernel cmdline parsing
2 Copyright (C) 2001 Rusty Russell.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17*/
18#include <linux/kernel.h>
19#include <linux/string.h>
20#include <linux/errno.h>
21#include <linux/module.h>
22#include <linux/moduleparam.h>
23#include <linux/device.h>
24#include <linux/err.h>
25#include <linux/slab.h>
26#include <linux/ctype.h>
27
28/* Protects all parameters, and incidentally kmalloced_param list. */
29static DEFINE_MUTEX(param_lock);
30
31/* This just allows us to keep track of which parameters are kmalloced. */
32struct kmalloced_param {
33 struct list_head list;
34 char val[];
35};
36static LIST_HEAD(kmalloced_params);
37
38static void *kmalloc_parameter(unsigned int size)
39{
40 struct kmalloced_param *p;
41
42 p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
43 if (!p)
44 return NULL;
45
46 list_add(&p->list, &kmalloced_params);
47 return p->val;
48}
49
50/* Does nothing if parameter wasn't kmalloced above. */
51static void maybe_kfree_parameter(void *param)
52{
53 struct kmalloced_param *p;
54
55 list_for_each_entry(p, &kmalloced_params, list) {
56 if (p->val == param) {
57 list_del(&p->list);
58 kfree(p);
59 break;
60 }
61 }
62}
63
64static char dash2underscore(char c)
65{
66 if (c == '-')
67 return '_';
68 return c;
69}
70
71bool parameqn(const char *a, const char *b, size_t n)
72{
73 size_t i;
74
75 for (i = 0; i < n; i++) {
76 if (dash2underscore(a[i]) != dash2underscore(b[i]))
77 return false;
78 }
79 return true;
80}
81
82bool parameq(const char *a, const char *b)
83{
84 return parameqn(a, b, strlen(a)+1);
85}
86
87static void param_check_unsafe(const struct kernel_param *kp)
88{
89 if (kp->flags & KERNEL_PARAM_FL_UNSAFE) {
90 pr_warn("Setting dangerous option %s - tainting kernel\n",
91 kp->name);
92 add_taint(TAINT_USER, LOCKDEP_STILL_OK);
93 }
94}
95
96static int parse_one(char *param,
97 char *val,
98 const char *doing,
99 const struct kernel_param *params,
100 unsigned num_params,
101 s16 min_level,
102 s16 max_level,
103 int (*handle_unknown)(char *param, char *val,
104 const char *doing))
105{
106 unsigned int i;
107 int err;
108
109 /* Find parameter */
110 for (i = 0; i < num_params; i++) {
111 if (parameq(param, params[i].name)) {
112 if (params[i].level < min_level
113 || params[i].level > max_level)
114 return 0;
115 /* No one handled NULL, so do it here. */
116 if (!val &&
117 !(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG))
118 return -EINVAL;
119 pr_debug("handling %s with %p\n", param,
120 params[i].ops->set);
121 mutex_lock(&param_lock);
122 param_check_unsafe(&params[i]);
123 err = params[i].ops->set(val, &params[i]);
124 mutex_unlock(&param_lock);
125 return err;
126 }
127 }
128
129 if (handle_unknown) {
130 pr_debug("doing %s: %s='%s'\n", doing, param, val);
131 return handle_unknown(param, val, doing);
132 }
133
134 pr_debug("Unknown argument '%s'\n", param);
135 return -ENOENT;
136}
137
138/* You can use " around spaces, but can't escape ". */
139/* Hyphens and underscores equivalent in parameter names. */
140static char *next_arg(char *args, char **param, char **val)
141{
142 unsigned int i, equals = 0;
143 int in_quote = 0, quoted = 0;
144 char *next;
145
146 if (*args == '"') {
147 args++;
148 in_quote = 1;
149 quoted = 1;
150 }
151
152 for (i = 0; args[i]; i++) {
153 if (isspace(args[i]) && !in_quote)
154 break;
155 if (equals == 0) {
156 if (args[i] == '=')
157 equals = i;
158 }
159 if (args[i] == '"')
160 in_quote = !in_quote;
161 }
162
163 *param = args;
164 if (!equals)
165 *val = NULL;
166 else {
167 args[equals] = '\0';
168 *val = args + equals + 1;
169
170 /* Don't include quotes in value. */
171 if (**val == '"') {
172 (*val)++;
173 if (args[i-1] == '"')
174 args[i-1] = '\0';
175 }
176 }
177 if (quoted && args[i-1] == '"')
178 args[i-1] = '\0';
179
180 if (args[i]) {
181 args[i] = '\0';
182 next = args + i + 1;
183 } else
184 next = args + i;
185
186 /* Chew up trailing spaces. */
187 return skip_spaces(next);
188}
189
190/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
191char *parse_args(const char *doing,
192 char *args,
193 const struct kernel_param *params,
194 unsigned num,
195 s16 min_level,
196 s16 max_level,
197 int (*unknown)(char *param, char *val, const char *doing))
198{
199 char *param, *val;
200
201 /* Chew leading spaces */
202 args = skip_spaces(args);
203
204 if (*args)
205 pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
206
207 while (*args) {
208 int ret;
209 int irq_was_disabled;
210
211 args = next_arg(args, &param, &val);
212 /* Stop at -- */
213 if (!val && strcmp(param, "--") == 0)
214 return args;
215 irq_was_disabled = irqs_disabled();
216 ret = parse_one(param, val, doing, params, num,
217 min_level, max_level, unknown);
218 if (irq_was_disabled && !irqs_disabled())
219 pr_warn("%s: option '%s' enabled irq's!\n",
220 doing, param);
221
222 switch (ret) {
223 case -ENOENT:
224 pr_err("%s: Unknown parameter `%s'\n", doing, param);
225 return ERR_PTR(ret);
226 case -ENOSPC:
227 pr_err("%s: `%s' too large for parameter `%s'\n",
228 doing, val ?: "", param);
229 return ERR_PTR(ret);
230 case 0:
231 break;
232 default:
233 pr_err("%s: `%s' invalid for parameter `%s'\n",
234 doing, val ?: "", param);
235 return ERR_PTR(ret);
236 }
237 }
238
239 /* All parsed OK. */
240 return NULL;
241}
242
243/* Lazy bastard, eh? */
244#define STANDARD_PARAM_DEF(name, type, format, strtolfn) \
245 int param_set_##name(const char *val, const struct kernel_param *kp) \
246 { \
247 return strtolfn(val, 0, (type *)kp->arg); \
248 } \
249 int param_get_##name(char *buffer, const struct kernel_param *kp) \
250 { \
251 return scnprintf(buffer, PAGE_SIZE, format, \
252 *((type *)kp->arg)); \
253 } \
254 struct kernel_param_ops param_ops_##name = { \
255 .set = param_set_##name, \
256 .get = param_get_##name, \
257 }; \
258 EXPORT_SYMBOL(param_set_##name); \
259 EXPORT_SYMBOL(param_get_##name); \
260 EXPORT_SYMBOL(param_ops_##name)
261
262
263STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8);
264STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16);
265STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16);
266STANDARD_PARAM_DEF(int, int, "%i", kstrtoint);
267STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint);
268STANDARD_PARAM_DEF(long, long, "%li", kstrtol);
269STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul);
270STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull);
271
272int param_set_charp(const char *val, const struct kernel_param *kp)
273{
274 if (strlen(val) > 1024) {
275 pr_err("%s: string parameter too long\n", kp->name);
276 return -ENOSPC;
277 }
278
279 maybe_kfree_parameter(*(char **)kp->arg);
280
281 /* This is a hack. We can't kmalloc in early boot, and we
282 * don't need to; this mangled commandline is preserved. */
283 if (slab_is_available()) {
284 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
285 if (!*(char **)kp->arg)
286 return -ENOMEM;
287 strcpy(*(char **)kp->arg, val);
288 } else
289 *(const char **)kp->arg = val;
290
291 return 0;
292}
293EXPORT_SYMBOL(param_set_charp);
294
295int param_get_charp(char *buffer, const struct kernel_param *kp)
296{
297 return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg));
298}
299EXPORT_SYMBOL(param_get_charp);
300
301static void param_free_charp(void *arg)
302{
303 maybe_kfree_parameter(*((char **)arg));
304}
305
306struct kernel_param_ops param_ops_charp = {
307 .set = param_set_charp,
308 .get = param_get_charp,
309 .free = param_free_charp,
310};
311EXPORT_SYMBOL(param_ops_charp);
312
313/* Actually could be a bool or an int, for historical reasons. */
314int param_set_bool(const char *val, const struct kernel_param *kp)
315{
316 /* No equals means "set"... */
317 if (!val) val = "1";
318
319 /* One of =[yYnN01] */
320 return strtobool(val, kp->arg);
321}
322EXPORT_SYMBOL(param_set_bool);
323
324int param_get_bool(char *buffer, const struct kernel_param *kp)
325{
326 /* Y and N chosen as being relatively non-coder friendly */
327 return sprintf(buffer, "%c", *(bool *)kp->arg ? 'Y' : 'N');
328}
329EXPORT_SYMBOL(param_get_bool);
330
331struct kernel_param_ops param_ops_bool = {
332 .flags = KERNEL_PARAM_OPS_FL_NOARG,
333 .set = param_set_bool,
334 .get = param_get_bool,
335};
336EXPORT_SYMBOL(param_ops_bool);
337
338/* This one must be bool. */
339int param_set_invbool(const char *val, const struct kernel_param *kp)
340{
341 int ret;
342 bool boolval;
343 struct kernel_param dummy;
344
345 dummy.arg = &boolval;
346 ret = param_set_bool(val, &dummy);
347 if (ret == 0)
348 *(bool *)kp->arg = !boolval;
349 return ret;
350}
351EXPORT_SYMBOL(param_set_invbool);
352
353int param_get_invbool(char *buffer, const struct kernel_param *kp)
354{
355 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
356}
357EXPORT_SYMBOL(param_get_invbool);
358
359struct kernel_param_ops param_ops_invbool = {
360 .set = param_set_invbool,
361 .get = param_get_invbool,
362};
363EXPORT_SYMBOL(param_ops_invbool);
364
365int param_set_bint(const char *val, const struct kernel_param *kp)
366{
367 struct kernel_param boolkp;
368 bool v;
369 int ret;
370
371 /* Match bool exactly, by re-using it. */
372 boolkp = *kp;
373 boolkp.arg = &v;
374
375 ret = param_set_bool(val, &boolkp);
376 if (ret == 0)
377 *(int *)kp->arg = v;
378 return ret;
379}
380EXPORT_SYMBOL(param_set_bint);
381
382struct kernel_param_ops param_ops_bint = {
383 .flags = KERNEL_PARAM_OPS_FL_NOARG,
384 .set = param_set_bint,
385 .get = param_get_int,
386};
387EXPORT_SYMBOL(param_ops_bint);
388
389/* We break the rule and mangle the string. */
390static int param_array(const char *name,
391 const char *val,
392 unsigned int min, unsigned int max,
393 void *elem, int elemsize,
394 int (*set)(const char *, const struct kernel_param *kp),
395 s16 level,
396 unsigned int *num)
397{
398 int ret;
399 struct kernel_param kp;
400 char save;
401
402 /* Get the name right for errors. */
403 kp.name = name;
404 kp.arg = elem;
405 kp.level = level;
406
407 *num = 0;
408 /* We expect a comma-separated list of values. */
409 do {
410 int len;
411
412 if (*num == max) {
413 pr_err("%s: can only take %i arguments\n", name, max);
414 return -EINVAL;
415 }
416 len = strcspn(val, ",");
417
418 /* nul-terminate and parse */
419 save = val[len];
420 ((char *)val)[len] = '\0';
421 BUG_ON(!mutex_is_locked(&param_lock));
422 ret = set(val, &kp);
423
424 if (ret != 0)
425 return ret;
426 kp.arg += elemsize;
427 val += len+1;
428 (*num)++;
429 } while (save == ',');
430
431 if (*num < min) {
432 pr_err("%s: needs at least %i arguments\n", name, min);
433 return -EINVAL;
434 }
435 return 0;
436}
437
438static int param_array_set(const char *val, const struct kernel_param *kp)
439{
440 const struct kparam_array *arr = kp->arr;
441 unsigned int temp_num;
442
443 return param_array(kp->name, val, 1, arr->max, arr->elem,
444 arr->elemsize, arr->ops->set, kp->level,
445 arr->num ?: &temp_num);
446}
447
448static int param_array_get(char *buffer, const struct kernel_param *kp)
449{
450 int i, off, ret;
451 const struct kparam_array *arr = kp->arr;
452 struct kernel_param p;
453
454 p = *kp;
455 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
456 if (i)
457 buffer[off++] = ',';
458 p.arg = arr->elem + arr->elemsize * i;
459 BUG_ON(!mutex_is_locked(&param_lock));
460 ret = arr->ops->get(buffer + off, &p);
461 if (ret < 0)
462 return ret;
463 off += ret;
464 }
465 buffer[off] = '\0';
466 return off;
467}
468
469static void param_array_free(void *arg)
470{
471 unsigned int i;
472 const struct kparam_array *arr = arg;
473
474 if (arr->ops->free)
475 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
476 arr->ops->free(arr->elem + arr->elemsize * i);
477}
478
479struct kernel_param_ops param_array_ops = {
480 .set = param_array_set,
481 .get = param_array_get,
482 .free = param_array_free,
483};
484EXPORT_SYMBOL(param_array_ops);
485
486int param_set_copystring(const char *val, const struct kernel_param *kp)
487{
488 const struct kparam_string *kps = kp->str;
489
490 if (strlen(val)+1 > kps->maxlen) {
491 pr_err("%s: string doesn't fit in %u chars.\n",
492 kp->name, kps->maxlen-1);
493 return -ENOSPC;
494 }
495 strcpy(kps->string, val);
496 return 0;
497}
498EXPORT_SYMBOL(param_set_copystring);
499
500int param_get_string(char *buffer, const struct kernel_param *kp)
501{
502 const struct kparam_string *kps = kp->str;
503 return strlcpy(buffer, kps->string, kps->maxlen);
504}
505EXPORT_SYMBOL(param_get_string);
506
507struct kernel_param_ops param_ops_string = {
508 .set = param_set_copystring,
509 .get = param_get_string,
510};
511EXPORT_SYMBOL(param_ops_string);
512
513/* sysfs output in /sys/modules/XYZ/parameters/ */
514#define to_module_attr(n) container_of(n, struct module_attribute, attr)
515#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
516
517struct param_attribute
518{
519 struct module_attribute mattr;
520 const struct kernel_param *param;
521};
522
523struct module_param_attrs
524{
525 unsigned int num;
526 struct attribute_group grp;
527 struct param_attribute attrs[0];
528};
529
530#ifdef CONFIG_SYSFS
531#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
532
533static ssize_t param_attr_show(struct module_attribute *mattr,
534 struct module_kobject *mk, char *buf)
535{
536 int count;
537 struct param_attribute *attribute = to_param_attr(mattr);
538
539 if (!attribute->param->ops->get)
540 return -EPERM;
541
542 mutex_lock(&param_lock);
543 count = attribute->param->ops->get(buf, attribute->param);
544 mutex_unlock(&param_lock);
545 if (count > 0) {
546 strcat(buf, "\n");
547 ++count;
548 }
549 return count;
550}
551
552/* sysfs always hands a nul-terminated string in buf. We rely on that. */
553static ssize_t param_attr_store(struct module_attribute *mattr,
554 struct module_kobject *km,
555 const char *buf, size_t len)
556{
557 int err;
558 struct param_attribute *attribute = to_param_attr(mattr);
559
560 if (!attribute->param->ops->set)
561 return -EPERM;
562
563 mutex_lock(&param_lock);
564 param_check_unsafe(attribute->param);
565 err = attribute->param->ops->set(buf, attribute->param);
566 mutex_unlock(&param_lock);
567 if (!err)
568 return len;
569 return err;
570}
571#endif
572
573#ifdef CONFIG_MODULES
574#define __modinit
575#else
576#define __modinit __init
577#endif
578
579#ifdef CONFIG_SYSFS
580void __kernel_param_lock(void)
581{
582 mutex_lock(&param_lock);
583}
584EXPORT_SYMBOL(__kernel_param_lock);
585
586void __kernel_param_unlock(void)
587{
588 mutex_unlock(&param_lock);
589}
590EXPORT_SYMBOL(__kernel_param_unlock);
591
592/*
593 * add_sysfs_param - add a parameter to sysfs
594 * @mk: struct module_kobject
595 * @kparam: the actual parameter definition to add to sysfs
596 * @name: name of parameter
597 *
598 * Create a kobject if for a (per-module) parameter if mp NULL, and
599 * create file in sysfs. Returns an error on out of memory. Always cleans up
600 * if there's an error.
601 */
602static __modinit int add_sysfs_param(struct module_kobject *mk,
603 const struct kernel_param *kp,
604 const char *name)
605{
606 struct module_param_attrs *new_mp;
607 struct attribute **new_attrs;
608 unsigned int i;
609
610 /* We don't bother calling this with invisible parameters. */
611 BUG_ON(!kp->perm);
612
613 if (!mk->mp) {
614 /* First allocation. */
615 mk->mp = kzalloc(sizeof(*mk->mp), GFP_KERNEL);
616 if (!mk->mp)
617 return -ENOMEM;
618 mk->mp->grp.name = "parameters";
619 /* NULL-terminated attribute array. */
620 mk->mp->grp.attrs = kzalloc(sizeof(mk->mp->grp.attrs[0]),
621 GFP_KERNEL);
622 /* Caller will cleanup via free_module_param_attrs */
623 if (!mk->mp->grp.attrs)
624 return -ENOMEM;
625 }
626
627 /* Enlarge allocations. */
628 new_mp = krealloc(mk->mp,
629 sizeof(*mk->mp) +
630 sizeof(mk->mp->attrs[0]) * (mk->mp->num + 1),
631 GFP_KERNEL);
632 if (!new_mp)
633 return -ENOMEM;
634 mk->mp = new_mp;
635
636 /* Extra pointer for NULL terminator */
637 new_attrs = krealloc(mk->mp->grp.attrs,
638 sizeof(mk->mp->grp.attrs[0]) * (mk->mp->num + 2),
639 GFP_KERNEL);
640 if (!new_attrs)
641 return -ENOMEM;
642 mk->mp->grp.attrs = new_attrs;
643
644 /* Tack new one on the end. */
645 memset(&mk->mp->attrs[mk->mp->num], 0, sizeof(mk->mp->attrs[0]));
646 sysfs_attr_init(&mk->mp->attrs[mk->mp->num].mattr.attr);
647 mk->mp->attrs[mk->mp->num].param = kp;
648 mk->mp->attrs[mk->mp->num].mattr.show = param_attr_show;
649 /* Do not allow runtime DAC changes to make param writable. */
650 if ((kp->perm & (S_IWUSR | S_IWGRP | S_IWOTH)) != 0)
651 mk->mp->attrs[mk->mp->num].mattr.store = param_attr_store;
652 else
653 mk->mp->attrs[mk->mp->num].mattr.store = NULL;
654 mk->mp->attrs[mk->mp->num].mattr.attr.name = (char *)name;
655 mk->mp->attrs[mk->mp->num].mattr.attr.mode = kp->perm;
656 mk->mp->num++;
657
658 /* Fix up all the pointers, since krealloc can move us */
659 for (i = 0; i < mk->mp->num; i++)
660 mk->mp->grp.attrs[i] = &mk->mp->attrs[i].mattr.attr;
661 mk->mp->grp.attrs[mk->mp->num] = NULL;
662 return 0;
663}
664
665#ifdef CONFIG_MODULES
666static void free_module_param_attrs(struct module_kobject *mk)
667{
668 if (mk->mp)
669 kfree(mk->mp->grp.attrs);
670 kfree(mk->mp);
671 mk->mp = NULL;
672}
673
674/*
675 * module_param_sysfs_setup - setup sysfs support for one module
676 * @mod: module
677 * @kparam: module parameters (array)
678 * @num_params: number of module parameters
679 *
680 * Adds sysfs entries for module parameters under
681 * /sys/module/[mod->name]/parameters/
682 */
683int module_param_sysfs_setup(struct module *mod,
684 const struct kernel_param *kparam,
685 unsigned int num_params)
686{
687 int i, err;
688 bool params = false;
689
690 for (i = 0; i < num_params; i++) {
691 if (kparam[i].perm == 0)
692 continue;
693 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
694 if (err) {
695 free_module_param_attrs(&mod->mkobj);
696 return err;
697 }
698 params = true;
699 }
700
701 if (!params)
702 return 0;
703
704 /* Create the param group. */
705 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
706 if (err)
707 free_module_param_attrs(&mod->mkobj);
708 return err;
709}
710
711/*
712 * module_param_sysfs_remove - remove sysfs support for one module
713 * @mod: module
714 *
715 * Remove sysfs entries for module parameters and the corresponding
716 * kobject.
717 */
718void module_param_sysfs_remove(struct module *mod)
719{
720 if (mod->mkobj.mp) {
721 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
722 /* We are positive that no one is using any param
723 * attrs at this point. Deallocate immediately. */
724 free_module_param_attrs(&mod->mkobj);
725 }
726}
727#endif
728
729void destroy_params(const struct kernel_param *params, unsigned num)
730{
731 unsigned int i;
732
733 for (i = 0; i < num; i++)
734 if (params[i].ops->free)
735 params[i].ops->free(params[i].arg);
736}
737
738static struct module_kobject * __init locate_module_kobject(const char *name)
739{
740 struct module_kobject *mk;
741 struct kobject *kobj;
742 int err;
743
744 kobj = kset_find_obj(module_kset, name);
745 if (kobj) {
746 mk = to_module_kobject(kobj);
747 } else {
748 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
749 BUG_ON(!mk);
750
751 mk->mod = THIS_MODULE;
752 mk->kobj.kset = module_kset;
753 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
754 "%s", name);
755#ifdef CONFIG_MODULES
756 if (!err)
757 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
758#endif
759 if (err) {
760 kobject_put(&mk->kobj);
761 pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n",
762 name, err);
763 return NULL;
764 }
765
766 /* So that we hold reference in both cases. */
767 kobject_get(&mk->kobj);
768 }
769
770 return mk;
771}
772
773static void __init kernel_add_sysfs_param(const char *name,
774 const struct kernel_param *kparam,
775 unsigned int name_skip)
776{
777 struct module_kobject *mk;
778 int err;
779
780 mk = locate_module_kobject(name);
781 if (!mk)
782 return;
783
784 /* We need to remove old parameters before adding more. */
785 if (mk->mp)
786 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
787
788 /* These should not fail at boot. */
789 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
790 BUG_ON(err);
791 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
792 BUG_ON(err);
793 kobject_uevent(&mk->kobj, KOBJ_ADD);
794 kobject_put(&mk->kobj);
795}
796
797/*
798 * param_sysfs_builtin - add sysfs parameters for built-in modules
799 *
800 * Add module_parameters to sysfs for "modules" built into the kernel.
801 *
802 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
803 * "parameter" name is stored behind a dot in kernel_param->name. So,
804 * extract the "module" name for all built-in kernel_param-eters,
805 * and for all who have the same, call kernel_add_sysfs_param.
806 */
807static void __init param_sysfs_builtin(void)
808{
809 const struct kernel_param *kp;
810 unsigned int name_len;
811 char modname[MODULE_NAME_LEN];
812
813 for (kp = __start___param; kp < __stop___param; kp++) {
814 char *dot;
815
816 if (kp->perm == 0)
817 continue;
818
819 dot = strchr(kp->name, '.');
820 if (!dot) {
821 /* This happens for core_param() */
822 strcpy(modname, "kernel");
823 name_len = 0;
824 } else {
825 name_len = dot - kp->name + 1;
826 strlcpy(modname, kp->name, name_len);
827 }
828 kernel_add_sysfs_param(modname, kp, name_len);
829 }
830}
831
832ssize_t __modver_version_show(struct module_attribute *mattr,
833 struct module_kobject *mk, char *buf)
834{
835 struct module_version_attribute *vattr =
836 container_of(mattr, struct module_version_attribute, mattr);
837
838 return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
839}
840
841extern const struct module_version_attribute *__start___modver[];
842extern const struct module_version_attribute *__stop___modver[];
843
844static void __init version_sysfs_builtin(void)
845{
846 const struct module_version_attribute **p;
847 struct module_kobject *mk;
848 int err;
849
850 for (p = __start___modver; p < __stop___modver; p++) {
851 const struct module_version_attribute *vattr = *p;
852
853 mk = locate_module_kobject(vattr->module_name);
854 if (mk) {
855 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
856 kobject_uevent(&mk->kobj, KOBJ_ADD);
857 kobject_put(&mk->kobj);
858 }
859 }
860}
861
862/* module-related sysfs stuff */
863
864static ssize_t module_attr_show(struct kobject *kobj,
865 struct attribute *attr,
866 char *buf)
867{
868 struct module_attribute *attribute;
869 struct module_kobject *mk;
870 int ret;
871
872 attribute = to_module_attr(attr);
873 mk = to_module_kobject(kobj);
874
875 if (!attribute->show)
876 return -EIO;
877
878 ret = attribute->show(attribute, mk, buf);
879
880 return ret;
881}
882
883static ssize_t module_attr_store(struct kobject *kobj,
884 struct attribute *attr,
885 const char *buf, size_t len)
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->store)
895 return -EIO;
896
897 ret = attribute->store(attribute, mk, buf, len);
898
899 return ret;
900}
901
902static const struct sysfs_ops module_sysfs_ops = {
903 .show = module_attr_show,
904 .store = module_attr_store,
905};
906
907static int uevent_filter(struct kset *kset, struct kobject *kobj)
908{
909 struct kobj_type *ktype = get_ktype(kobj);
910
911 if (ktype == &module_ktype)
912 return 1;
913 return 0;
914}
915
916static const struct kset_uevent_ops module_uevent_ops = {
917 .filter = uevent_filter,
918};
919
920struct kset *module_kset;
921int module_sysfs_initialized;
922
923static void module_kobj_release(struct kobject *kobj)
924{
925 struct module_kobject *mk = to_module_kobject(kobj);
926 complete(mk->kobj_completion);
927}
928
929struct kobj_type module_ktype = {
930 .release = module_kobj_release,
931 .sysfs_ops = &module_sysfs_ops,
932};
933
934/*
935 * param_sysfs_init - wrapper for built-in params support
936 */
937static int __init param_sysfs_init(void)
938{
939 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
940 if (!module_kset) {
941 printk(KERN_WARNING "%s (%d): error creating kset\n",
942 __FILE__, __LINE__);
943 return -ENOMEM;
944 }
945 module_sysfs_initialized = 1;
946
947 version_sysfs_builtin();
948 param_sysfs_builtin();
949
950 return 0;
951}
952subsys_initcall(param_sysfs_init);
953
954#endif /* CONFIG_SYSFS */