projects/linux·blob v3.3-rc2 · 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/module.h>
19#include <linux/kernel.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/module.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 int parse_one(char *param,
88 char *val,
89 const struct kernel_param *params,
90 unsigned num_params,
91 int (*handle_unknown)(char *param, char *val))
92{
93 unsigned int i;
94 int err;
95
96 /* Find parameter */
97 for (i = 0; i < num_params; i++) {
98 if (parameq(param, params[i].name)) {
99 /* No one handled NULL, so do it here. */
100 if (!val && params[i].ops->set != param_set_bool)
101 return -EINVAL;
102 pr_debug("They are equal! Calling %p\n",
103 params[i].ops->set);
104 mutex_lock(&param_lock);
105 err = params[i].ops->set(val, &params[i]);
106 mutex_unlock(&param_lock);
107 return err;
108 }
109 }
110
111 if (handle_unknown) {
112 pr_debug("Unknown argument: calling %p\n", handle_unknown);
113 return handle_unknown(param, val);
114 }
115
116 pr_debug("Unknown argument `%s'\n", param);
117 return -ENOENT;
118}
119
120/* You can use " around spaces, but can't escape ". */
121/* Hyphens and underscores equivalent in parameter names. */
122static char *next_arg(char *args, char **param, char **val)
123{
124 unsigned int i, equals = 0;
125 int in_quote = 0, quoted = 0;
126 char *next;
127
128 if (*args == '"') {
129 args++;
130 in_quote = 1;
131 quoted = 1;
132 }
133
134 for (i = 0; args[i]; i++) {
135 if (isspace(args[i]) && !in_quote)
136 break;
137 if (equals == 0) {
138 if (args[i] == '=')
139 equals = i;
140 }
141 if (args[i] == '"')
142 in_quote = !in_quote;
143 }
144
145 *param = args;
146 if (!equals)
147 *val = NULL;
148 else {
149 args[equals] = '\0';
150 *val = args + equals + 1;
151
152 /* Don't include quotes in value. */
153 if (**val == '"') {
154 (*val)++;
155 if (args[i-1] == '"')
156 args[i-1] = '\0';
157 }
158 if (quoted && args[i-1] == '"')
159 args[i-1] = '\0';
160 }
161
162 if (args[i]) {
163 args[i] = '\0';
164 next = args + i + 1;
165 } else
166 next = args + i;
167
168 /* Chew up trailing spaces. */
169 return skip_spaces(next);
170}
171
172/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
173int parse_args(const char *name,
174 char *args,
175 const struct kernel_param *params,
176 unsigned num,
177 int (*unknown)(char *param, char *val))
178{
179 char *param, *val;
180
181 pr_debug("Parsing ARGS: %s\n", args);
182
183 /* Chew leading spaces */
184 args = skip_spaces(args);
185
186 while (*args) {
187 int ret;
188 int irq_was_disabled;
189
190 args = next_arg(args, &param, &val);
191 irq_was_disabled = irqs_disabled();
192 ret = parse_one(param, val, params, num, unknown);
193 if (irq_was_disabled && !irqs_disabled()) {
194 printk(KERN_WARNING "parse_args(): option '%s' enabled "
195 "irq's!\n", param);
196 }
197 switch (ret) {
198 case -ENOENT:
199 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
200 name, param);
201 return ret;
202 case -ENOSPC:
203 printk(KERN_ERR
204 "%s: `%s' too large for parameter `%s'\n",
205 name, val ?: "", param);
206 return ret;
207 case 0:
208 break;
209 default:
210 printk(KERN_ERR
211 "%s: `%s' invalid for parameter `%s'\n",
212 name, val ?: "", param);
213 return ret;
214 }
215 }
216
217 /* All parsed OK. */
218 return 0;
219}
220
221/* Lazy bastard, eh? */
222#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
223 int param_set_##name(const char *val, const struct kernel_param *kp) \
224 { \
225 tmptype l; \
226 int ret; \
227 \
228 ret = strtolfn(val, 0, &l); \
229 if (ret < 0 || ((type)l != l)) \
230 return ret < 0 ? ret : -EINVAL; \
231 *((type *)kp->arg) = l; \
232 return 0; \
233 } \
234 int param_get_##name(char *buffer, const struct kernel_param *kp) \
235 { \
236 return sprintf(buffer, format, *((type *)kp->arg)); \
237 } \
238 struct kernel_param_ops param_ops_##name = { \
239 .set = param_set_##name, \
240 .get = param_get_##name, \
241 }; \
242 EXPORT_SYMBOL(param_set_##name); \
243 EXPORT_SYMBOL(param_get_##name); \
244 EXPORT_SYMBOL(param_ops_##name)
245
246
247STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
248STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
249STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
250STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
251STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
252STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
253STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
254
255int param_set_charp(const char *val, const struct kernel_param *kp)
256{
257 if (strlen(val) > 1024) {
258 printk(KERN_ERR "%s: string parameter too long\n",
259 kp->name);
260 return -ENOSPC;
261 }
262
263 maybe_kfree_parameter(*(char **)kp->arg);
264
265 /* This is a hack. We can't kmalloc in early boot, and we
266 * don't need to; this mangled commandline is preserved. */
267 if (slab_is_available()) {
268 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
269 if (!*(char **)kp->arg)
270 return -ENOMEM;
271 strcpy(*(char **)kp->arg, val);
272 } else
273 *(const char **)kp->arg = val;
274
275 return 0;
276}
277EXPORT_SYMBOL(param_set_charp);
278
279int param_get_charp(char *buffer, const struct kernel_param *kp)
280{
281 return sprintf(buffer, "%s", *((char **)kp->arg));
282}
283EXPORT_SYMBOL(param_get_charp);
284
285static void param_free_charp(void *arg)
286{
287 maybe_kfree_parameter(*((char **)arg));
288}
289
290struct kernel_param_ops param_ops_charp = {
291 .set = param_set_charp,
292 .get = param_get_charp,
293 .free = param_free_charp,
294};
295EXPORT_SYMBOL(param_ops_charp);
296
297/* Actually could be a bool or an int, for historical reasons. */
298int param_set_bool(const char *val, const struct kernel_param *kp)
299{
300 bool v;
301 int ret;
302
303 /* No equals means "set"... */
304 if (!val) val = "1";
305
306 /* One of =[yYnN01] */
307 ret = strtobool(val, &v);
308 if (ret)
309 return ret;
310
311 if (kp->flags & KPARAM_ISBOOL)
312 *(bool *)kp->arg = v;
313 else
314 *(int *)kp->arg = v;
315 return 0;
316}
317EXPORT_SYMBOL(param_set_bool);
318
319int param_get_bool(char *buffer, const struct kernel_param *kp)
320{
321 bool val;
322 if (kp->flags & KPARAM_ISBOOL)
323 val = *(bool *)kp->arg;
324 else
325 val = *(int *)kp->arg;
326
327 /* Y and N chosen as being relatively non-coder friendly */
328 return sprintf(buffer, "%c", val ? 'Y' : 'N');
329}
330EXPORT_SYMBOL(param_get_bool);
331
332struct kernel_param_ops param_ops_bool = {
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 dummy.flags = KPARAM_ISBOOL;
347 ret = param_set_bool(val, &dummy);
348 if (ret == 0)
349 *(bool *)kp->arg = !boolval;
350 return ret;
351}
352EXPORT_SYMBOL(param_set_invbool);
353
354int param_get_invbool(char *buffer, const struct kernel_param *kp)
355{
356 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
357}
358EXPORT_SYMBOL(param_get_invbool);
359
360struct kernel_param_ops param_ops_invbool = {
361 .set = param_set_invbool,
362 .get = param_get_invbool,
363};
364EXPORT_SYMBOL(param_ops_invbool);
365
366int param_set_bint(const char *val, const struct kernel_param *kp)
367{
368 struct kernel_param boolkp;
369 bool v;
370 int ret;
371
372 /* Match bool exactly, by re-using it. */
373 boolkp = *kp;
374 boolkp.arg = &v;
375 boolkp.flags |= KPARAM_ISBOOL;
376
377 ret = param_set_bool(val, &boolkp);
378 if (ret == 0)
379 *(int *)kp->arg = v;
380 return ret;
381}
382EXPORT_SYMBOL(param_set_bint);
383
384struct kernel_param_ops param_ops_bint = {
385 .set = param_set_bint,
386 .get = param_get_int,
387};
388EXPORT_SYMBOL(param_ops_bint);
389
390/* We break the rule and mangle the string. */
391static int param_array(const char *name,
392 const char *val,
393 unsigned int min, unsigned int max,
394 void *elem, int elemsize,
395 int (*set)(const char *, const struct kernel_param *kp),
396 u16 flags,
397 unsigned int *num)
398{
399 int ret;
400 struct kernel_param kp;
401 char save;
402
403 /* Get the name right for errors. */
404 kp.name = name;
405 kp.arg = elem;
406 kp.flags = flags;
407
408 *num = 0;
409 /* We expect a comma-separated list of values. */
410 do {
411 int len;
412
413 if (*num == max) {
414 printk(KERN_ERR "%s: can only take %i arguments\n",
415 name, max);
416 return -EINVAL;
417 }
418 len = strcspn(val, ",");
419
420 /* nul-terminate and parse */
421 save = val[len];
422 ((char *)val)[len] = '\0';
423 BUG_ON(!mutex_is_locked(&param_lock));
424 ret = set(val, &kp);
425
426 if (ret != 0)
427 return ret;
428 kp.arg += elemsize;
429 val += len+1;
430 (*num)++;
431 } while (save == ',');
432
433 if (*num < min) {
434 printk(KERN_ERR "%s: needs at least %i arguments\n",
435 name, min);
436 return -EINVAL;
437 }
438 return 0;
439}
440
441static int param_array_set(const char *val, const struct kernel_param *kp)
442{
443 const struct kparam_array *arr = kp->arr;
444 unsigned int temp_num;
445
446 return param_array(kp->name, val, 1, arr->max, arr->elem,
447 arr->elemsize, arr->ops->set, kp->flags,
448 arr->num ?: &temp_num);
449}
450
451static int param_array_get(char *buffer, const struct kernel_param *kp)
452{
453 int i, off, ret;
454 const struct kparam_array *arr = kp->arr;
455 struct kernel_param p;
456
457 p = *kp;
458 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
459 if (i)
460 buffer[off++] = ',';
461 p.arg = arr->elem + arr->elemsize * i;
462 BUG_ON(!mutex_is_locked(&param_lock));
463 ret = arr->ops->get(buffer + off, &p);
464 if (ret < 0)
465 return ret;
466 off += ret;
467 }
468 buffer[off] = '\0';
469 return off;
470}
471
472static void param_array_free(void *arg)
473{
474 unsigned int i;
475 const struct kparam_array *arr = arg;
476
477 if (arr->ops->free)
478 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
479 arr->ops->free(arr->elem + arr->elemsize * i);
480}
481
482struct kernel_param_ops param_array_ops = {
483 .set = param_array_set,
484 .get = param_array_get,
485 .free = param_array_free,
486};
487EXPORT_SYMBOL(param_array_ops);
488
489int param_set_copystring(const char *val, const struct kernel_param *kp)
490{
491 const struct kparam_string *kps = kp->str;
492
493 if (strlen(val)+1 > kps->maxlen) {
494 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
495 kp->name, kps->maxlen-1);
496 return -ENOSPC;
497 }
498 strcpy(kps->string, val);
499 return 0;
500}
501EXPORT_SYMBOL(param_set_copystring);
502
503int param_get_string(char *buffer, const struct kernel_param *kp)
504{
505 const struct kparam_string *kps = kp->str;
506 return strlcpy(buffer, kps->string, kps->maxlen);
507}
508EXPORT_SYMBOL(param_get_string);
509
510struct kernel_param_ops param_ops_string = {
511 .set = param_set_copystring,
512 .get = param_get_string,
513};
514EXPORT_SYMBOL(param_ops_string);
515
516/* sysfs output in /sys/modules/XYZ/parameters/ */
517#define to_module_attr(n) container_of(n, struct module_attribute, attr)
518#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
519
520extern struct kernel_param __start___param[], __stop___param[];
521
522struct param_attribute
523{
524 struct module_attribute mattr;
525 const struct kernel_param *param;
526};
527
528struct module_param_attrs
529{
530 unsigned int num;
531 struct attribute_group grp;
532 struct param_attribute attrs[0];
533};
534
535#ifdef CONFIG_SYSFS
536#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
537
538static ssize_t param_attr_show(struct module_attribute *mattr,
539 struct module_kobject *mk, char *buf)
540{
541 int count;
542 struct param_attribute *attribute = to_param_attr(mattr);
543
544 if (!attribute->param->ops->get)
545 return -EPERM;
546
547 mutex_lock(&param_lock);
548 count = attribute->param->ops->get(buf, attribute->param);
549 mutex_unlock(&param_lock);
550 if (count > 0) {
551 strcat(buf, "\n");
552 ++count;
553 }
554 return count;
555}
556
557/* sysfs always hands a nul-terminated string in buf. We rely on that. */
558static ssize_t param_attr_store(struct module_attribute *mattr,
559 struct module_kobject *km,
560 const char *buf, size_t len)
561{
562 int err;
563 struct param_attribute *attribute = to_param_attr(mattr);
564
565 if (!attribute->param->ops->set)
566 return -EPERM;
567
568 mutex_lock(&param_lock);
569 err = attribute->param->ops->set(buf, attribute->param);
570 mutex_unlock(&param_lock);
571 if (!err)
572 return len;
573 return err;
574}
575#endif
576
577#ifdef CONFIG_MODULES
578#define __modinit
579#else
580#define __modinit __init
581#endif
582
583#ifdef CONFIG_SYSFS
584void __kernel_param_lock(void)
585{
586 mutex_lock(&param_lock);
587}
588EXPORT_SYMBOL(__kernel_param_lock);
589
590void __kernel_param_unlock(void)
591{
592 mutex_unlock(&param_lock);
593}
594EXPORT_SYMBOL(__kernel_param_unlock);
595
596/*
597 * add_sysfs_param - add a parameter to sysfs
598 * @mk: struct module_kobject
599 * @kparam: the actual parameter definition to add to sysfs
600 * @name: name of parameter
601 *
602 * Create a kobject if for a (per-module) parameter if mp NULL, and
603 * create file in sysfs. Returns an error on out of memory. Always cleans up
604 * if there's an error.
605 */
606static __modinit int add_sysfs_param(struct module_kobject *mk,
607 const struct kernel_param *kp,
608 const char *name)
609{
610 struct module_param_attrs *new;
611 struct attribute **attrs;
612 int err, num;
613
614 /* We don't bother calling this with invisible parameters. */
615 BUG_ON(!kp->perm);
616
617 if (!mk->mp) {
618 num = 0;
619 attrs = NULL;
620 } else {
621 num = mk->mp->num;
622 attrs = mk->mp->grp.attrs;
623 }
624
625 /* Enlarge. */
626 new = krealloc(mk->mp,
627 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
628 GFP_KERNEL);
629 if (!new) {
630 kfree(mk->mp);
631 err = -ENOMEM;
632 goto fail;
633 }
634 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
635 if (!attrs) {
636 err = -ENOMEM;
637 goto fail_free_new;
638 }
639
640 /* Sysfs wants everything zeroed. */
641 memset(new, 0, sizeof(*new));
642 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
643 memset(&attrs[num], 0, sizeof(attrs[num]));
644 new->grp.name = "parameters";
645 new->grp.attrs = attrs;
646
647 /* Tack new one on the end. */
648 sysfs_attr_init(&new->attrs[num].mattr.attr);
649 new->attrs[num].param = kp;
650 new->attrs[num].mattr.show = param_attr_show;
651 new->attrs[num].mattr.store = param_attr_store;
652 new->attrs[num].mattr.attr.name = (char *)name;
653 new->attrs[num].mattr.attr.mode = kp->perm;
654 new->num = num+1;
655
656 /* Fix up all the pointers, since krealloc can move us */
657 for (num = 0; num < new->num; num++)
658 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
659 new->grp.attrs[num] = NULL;
660
661 mk->mp = new;
662 return 0;
663
664fail_free_new:
665 kfree(new);
666fail:
667 mk->mp = NULL;
668 return err;
669}
670
671#ifdef CONFIG_MODULES
672static void free_module_param_attrs(struct module_kobject *mk)
673{
674 kfree(mk->mp->grp.attrs);
675 kfree(mk->mp);
676 mk->mp = NULL;
677}
678
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 *
685 * Adds sysfs entries for module parameters under
686 * /sys/module/[mod->name]/parameters/
687 */
688int module_param_sysfs_setup(struct module *mod,
689 const struct kernel_param *kparam,
690 unsigned int num_params)
691{
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);
699 if (err)
700 return err;
701 params = true;
702 }
703
704 if (!params)
705 return 0;
706
707 /* Create the param group. */
708 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
709 if (err)
710 free_module_param_attrs(&mod->mkobj);
711 return err;
712}
713
714/*
715 * module_param_sysfs_remove - remove sysfs support for one module
716 * @mod: module
717 *
718 * Remove sysfs entries for module parameters and the corresponding
719 * kobject.
720 */
721void module_param_sysfs_remove(struct module *mod)
722{
723 if (mod->mkobj.mp) {
724 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
725 /* We are positive that no one is using any param
726 * attrs at this point. Deallocate immediately. */
727 free_module_param_attrs(&mod->mkobj);
728 }
729}
730#endif
731
732void destroy_params(const struct kernel_param *params, unsigned num)
733{
734 unsigned int i;
735
736 for (i = 0; i < num; i++)
737 if (params[i].ops->free)
738 params[i].ops->free(params[i].arg);
739}
740
741static struct module_kobject * __init locate_module_kobject(const char *name)
742{
743 struct module_kobject *mk;
744 struct kobject *kobj;
745 int err;
746
747 kobj = kset_find_obj(module_kset, name);
748 if (kobj) {
749 mk = to_module_kobject(kobj);
750 } else {
751 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
752 BUG_ON(!mk);
753
754 mk->mod = THIS_MODULE;
755 mk->kobj.kset = module_kset;
756 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
757 "%s", name);
758#ifdef CONFIG_MODULES
759 if (!err)
760 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
761#endif
762 if (err) {
763 kobject_put(&mk->kobj);
764 printk(KERN_ERR
765 "Module '%s' failed add to sysfs, error number %d\n",
766 name, err);
767 printk(KERN_ERR
768 "The system will be unstable now.\n");
769 return NULL;
770 }
771
772 /* So that we hold reference in both cases. */
773 kobject_get(&mk->kobj);
774 }
775
776 return mk;
777}
778
779static void __init kernel_add_sysfs_param(const char *name,
780 struct kernel_param *kparam,
781 unsigned int name_skip)
782{
783 struct module_kobject *mk;
784 int err;
785
786 mk = locate_module_kobject(name);
787 if (!mk)
788 return;
789
790 /* We need to remove old parameters before adding more. */
791 if (mk->mp)
792 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
793
794 /* These should not fail at boot. */
795 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
796 BUG_ON(err);
797 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
798 BUG_ON(err);
799 kobject_uevent(&mk->kobj, KOBJ_ADD);
800 kobject_put(&mk->kobj);
801}
802
803/*
804 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
805 *
806 * Add module_parameters to sysfs for "modules" built into the kernel.
807 *
808 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
809 * "parameter" name is stored behind a dot in kernel_param->name. So,
810 * extract the "module" name for all built-in kernel_param-eters,
811 * and for all who have the same, call kernel_add_sysfs_param.
812 */
813static void __init param_sysfs_builtin(void)
814{
815 struct kernel_param *kp;
816 unsigned int name_len;
817 char modname[MODULE_NAME_LEN];
818
819 for (kp = __start___param; kp < __stop___param; kp++) {
820 char *dot;
821
822 if (kp->perm == 0)
823 continue;
824
825 dot = strchr(kp->name, '.');
826 if (!dot) {
827 /* This happens for core_param() */
828 strcpy(modname, "kernel");
829 name_len = 0;
830 } else {
831 name_len = dot - kp->name + 1;
832 strlcpy(modname, kp->name, name_len);
833 }
834 kernel_add_sysfs_param(modname, kp, name_len);
835 }
836}
837
838ssize_t __modver_version_show(struct module_attribute *mattr,
839 struct module_kobject *mk, char *buf)
840{
841 struct module_version_attribute *vattr =
842 container_of(mattr, struct module_version_attribute, mattr);
843
844 return sprintf(buf, "%s\n", vattr->version);
845}
846
847extern const struct module_version_attribute *__start___modver[];
848extern const struct module_version_attribute *__stop___modver[];
849
850static void __init version_sysfs_builtin(void)
851{
852 const struct module_version_attribute **p;
853 struct module_kobject *mk;
854 int err;
855
856 for (p = __start___modver; p < __stop___modver; p++) {
857 const struct module_version_attribute *vattr = *p;
858
859 mk = locate_module_kobject(vattr->module_name);
860 if (mk) {
861 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
862 kobject_uevent(&mk->kobj, KOBJ_ADD);
863 kobject_put(&mk->kobj);
864 }
865 }
866}
867
868/* module-related sysfs stuff */
869
870static ssize_t module_attr_show(struct kobject *kobj,
871 struct attribute *attr,
872 char *buf)
873{
874 struct module_attribute *attribute;
875 struct module_kobject *mk;
876 int ret;
877
878 attribute = to_module_attr(attr);
879 mk = to_module_kobject(kobj);
880
881 if (!attribute->show)
882 return -EIO;
883
884 ret = attribute->show(attribute, mk, buf);
885
886 return ret;
887}
888
889static ssize_t module_attr_store(struct kobject *kobj,
890 struct attribute *attr,
891 const char *buf, size_t len)
892{
893 struct module_attribute *attribute;
894 struct module_kobject *mk;
895 int ret;
896
897 attribute = to_module_attr(attr);
898 mk = to_module_kobject(kobj);
899
900 if (!attribute->store)
901 return -EIO;
902
903 ret = attribute->store(attribute, mk, buf, len);
904
905 return ret;
906}
907
908static const struct sysfs_ops module_sysfs_ops = {
909 .show = module_attr_show,
910 .store = module_attr_store,
911};
912
913static int uevent_filter(struct kset *kset, struct kobject *kobj)
914{
915 struct kobj_type *ktype = get_ktype(kobj);
916
917 if (ktype == &module_ktype)
918 return 1;
919 return 0;
920}
921
922static const struct kset_uevent_ops module_uevent_ops = {
923 .filter = uevent_filter,
924};
925
926struct kset *module_kset;
927int module_sysfs_initialized;
928
929struct kobj_type module_ktype = {
930 .sysfs_ops = &module_sysfs_ops,
931};
932
933/*
934 * param_sysfs_init - wrapper for built-in params support
935 */
936static int __init param_sysfs_init(void)
937{
938 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
939 if (!module_kset) {
940 printk(KERN_WARNING "%s (%d): error creating kset\n",
941 __FILE__, __LINE__);
942 return -ENOMEM;
943 }
944 module_sysfs_initialized = 1;
945
946 version_sysfs_builtin();
947 param_sysfs_builtin();
948
949 return 0;
950}
951subsys_initcall(param_sysfs_init);
952
953#endif /* CONFIG_SYSFS */