]> git.ipfire.org Git - people/ms/linux.git/blame - kernel/params.c
module_param: check type correctness for module_param_array
[people/ms/linux.git] / kernel / params.c
CommitLineData
1da177e4
LT
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*/
72a59aaa 18#include <linux/module.h>
1da177e4
LT
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>
4e57b681 25#include <linux/slab.h>
26d052bf 26#include <linux/ctype.h>
1da177e4 27
907b29eb
RR
28/* Protects all parameters, and incidentally kmalloced_param list. */
29static DEFINE_MUTEX(param_lock);
30
a1054322
RR
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};
a1054322
RR
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
a1054322 46 list_add(&p->list, &kmalloced_params);
a1054322
RR
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
a1054322
RR
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 }
a1054322
RR
62}
63
b1e4d20c 64static char dash2underscore(char c)
1da177e4
LT
65{
66 if (c == '-')
67 return '_';
68 return c;
69}
70
b1e4d20c 71bool parameqn(const char *a, const char *b, size_t n)
1da177e4 72{
b1e4d20c
MS
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);
1da177e4
LT
85}
86
87static int parse_one(char *param,
88 char *val,
914dcaa8 89 const struct kernel_param *params,
1da177e4
LT
90 unsigned num_params,
91 int (*handle_unknown)(char *param, char *val))
92{
93 unsigned int i;
907b29eb 94 int err;
1da177e4
LT
95
96 /* Find parameter */
97 for (i = 0; i < num_params; i++) {
98 if (parameq(param, params[i].name)) {
25985edc 99 /* No one handled NULL, so do it here. */
9bbb9e5a 100 if (!val && params[i].ops->set != param_set_bool)
2e9fb995 101 return -EINVAL;
8487bfd9 102 pr_debug("They are equal! Calling %p\n",
9bbb9e5a 103 params[i].ops->set);
907b29eb
RR
104 mutex_lock(&param_lock);
105 err = params[i].ops->set(val, &params[i]);
106 mutex_unlock(&param_lock);
107 return err;
1da177e4
LT
108 }
109 }
110
111 if (handle_unknown) {
8487bfd9 112 pr_debug("Unknown argument: calling %p\n", handle_unknown);
1da177e4
LT
113 return handle_unknown(param, val);
114 }
115
8487bfd9 116 pr_debug("Unknown argument `%s'\n", param);
1da177e4
LT
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
1da177e4
LT
128 if (*args == '"') {
129 args++;
130 in_quote = 1;
131 quoted = 1;
132 }
133
134 for (i = 0; args[i]; i++) {
26d052bf 135 if (isspace(args[i]) && !in_quote)
1da177e4
LT
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;
f36462f0
RR
167
168 /* Chew up trailing spaces. */
e7d2860b 169 return skip_spaces(next);
1da177e4
LT
170}
171
172/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
173int parse_args(const char *name,
174 char *args,
914dcaa8 175 const struct kernel_param *params,
1da177e4
LT
176 unsigned num,
177 int (*unknown)(char *param, char *val))
178{
179 char *param, *val;
180
8487bfd9 181 pr_debug("Parsing ARGS: %s\n", args);
1da177e4 182
f36462f0 183 /* Chew leading spaces */
e7d2860b 184 args = skip_spaces(args);
f36462f0 185
1da177e4
LT
186 while (*args) {
187 int ret;
a416aba6 188 int irq_was_disabled;
1da177e4
LT
189
190 args = next_arg(args, &param, &val);
a416aba6 191 irq_was_disabled = irqs_disabled();
1da177e4 192 ret = parse_one(param, val, params, num, unknown);
a416aba6
AB
193 if (irq_was_disabled && !irqs_disabled()) {
194 printk(KERN_WARNING "parse_args(): option '%s' enabled "
195 "irq's!\n", param);
196 }
1da177e4
LT
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) \
9bbb9e5a 223 int param_set_##name(const char *val, const struct kernel_param *kp) \
1da177e4 224 { \
1da177e4 225 tmptype l; \
06b2a76d 226 int ret; \
1da177e4 227 \
06b2a76d 228 ret = strtolfn(val, 0, &l); \
81c74136
SM
229 if (ret < 0 || ((type)l != l)) \
230 return ret < 0 ? ret : -EINVAL; \
1da177e4
LT
231 *((type *)kp->arg) = l; \
232 return 0; \
233 } \
9bbb9e5a 234 int param_get_##name(char *buffer, const struct kernel_param *kp) \
1da177e4
LT
235 { \
236 return sprintf(buffer, format, *((type *)kp->arg)); \
a14fe249 237 } \
9bbb9e5a
RR
238 struct kernel_param_ops param_ops_##name = { \
239 .set = param_set_##name, \
240 .get = param_get_##name, \
241 }; \
a14fe249 242 EXPORT_SYMBOL(param_set_##name); \
9bbb9e5a
RR
243 EXPORT_SYMBOL(param_get_##name); \
244 EXPORT_SYMBOL(param_ops_##name)
245
1da177e4 246
06b2a76d
YY
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);
1da177e4 254
9bbb9e5a 255int param_set_charp(const char *val, const struct kernel_param *kp)
1da177e4 256{
1da177e4
LT
257 if (strlen(val) > 1024) {
258 printk(KERN_ERR "%s: string parameter too long\n",
259 kp->name);
260 return -ENOSPC;
261 }
262
a1054322
RR
263 maybe_kfree_parameter(*(char **)kp->arg);
264
265 /* This is a hack. We can't kmalloc in early boot, and we
e180a6b7
RR
266 * don't need to; this mangled commandline is preserved. */
267 if (slab_is_available()) {
a1054322 268 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
d553ad86 269 if (!*(char **)kp->arg)
e180a6b7 270 return -ENOMEM;
a1054322 271 strcpy(*(char **)kp->arg, val);
e180a6b7
RR
272 } else
273 *(const char **)kp->arg = val;
274
1da177e4
LT
275 return 0;
276}
a14fe249 277EXPORT_SYMBOL(param_set_charp);
1da177e4 278
9bbb9e5a 279int param_get_charp(char *buffer, const struct kernel_param *kp)
1da177e4
LT
280{
281 return sprintf(buffer, "%s", *((char **)kp->arg));
282}
a14fe249 283EXPORT_SYMBOL(param_get_charp);
1da177e4 284
a1054322
RR
285static void param_free_charp(void *arg)
286{
287 maybe_kfree_parameter(*((char **)arg));
288}
289
9bbb9e5a
RR
290struct kernel_param_ops param_ops_charp = {
291 .set = param_set_charp,
292 .get = param_get_charp,
a1054322 293 .free = param_free_charp,
9bbb9e5a
RR
294};
295EXPORT_SYMBOL(param_ops_charp);
296
fddd5201 297/* Actually could be a bool or an int, for historical reasons. */
9bbb9e5a 298int param_set_bool(const char *val, const struct kernel_param *kp)
1da177e4 299{
fddd5201 300 bool v;
f721a465 301 int ret;
fddd5201 302
1da177e4
LT
303 /* No equals means "set"... */
304 if (!val) val = "1";
305
306 /* One of =[yYnN01] */
f721a465
JC
307 ret = strtobool(val, &v);
308 if (ret)
309 return ret;
fddd5201
RR
310
311 if (kp->flags & KPARAM_ISBOOL)
312 *(bool *)kp->arg = v;
313 else
314 *(int *)kp->arg = v;
315 return 0;
1da177e4 316}
a14fe249 317EXPORT_SYMBOL(param_set_bool);
1da177e4 318
9bbb9e5a 319int param_get_bool(char *buffer, const struct kernel_param *kp)
1da177e4 320{
fddd5201
RR
321 bool val;
322 if (kp->flags & KPARAM_ISBOOL)
323 val = *(bool *)kp->arg;
324 else
325 val = *(int *)kp->arg;
326
1da177e4 327 /* Y and N chosen as being relatively non-coder friendly */
fddd5201 328 return sprintf(buffer, "%c", val ? 'Y' : 'N');
1da177e4 329}
a14fe249 330EXPORT_SYMBOL(param_get_bool);
1da177e4 331
9bbb9e5a
RR
332struct kernel_param_ops param_ops_bool = {
333 .set = param_set_bool,
334 .get = param_get_bool,
335};
336EXPORT_SYMBOL(param_ops_bool);
337
fddd5201 338/* This one must be bool. */
9bbb9e5a 339int param_set_invbool(const char *val, const struct kernel_param *kp)
1da177e4 340{
fddd5201
RR
341 int ret;
342 bool boolval;
22e48eaf 343 struct kernel_param dummy;
1da177e4 344
22e48eaf 345 dummy.arg = &boolval;
fddd5201 346 dummy.flags = KPARAM_ISBOOL;
1da177e4
LT
347 ret = param_set_bool(val, &dummy);
348 if (ret == 0)
9a71af2c 349 *(bool *)kp->arg = !boolval;
1da177e4
LT
350 return ret;
351}
a14fe249 352EXPORT_SYMBOL(param_set_invbool);
1da177e4 353
9bbb9e5a 354int param_get_invbool(char *buffer, const struct kernel_param *kp)
1da177e4 355{
9a71af2c 356 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
1da177e4 357}
a14fe249 358EXPORT_SYMBOL(param_get_invbool);
1da177e4 359
9bbb9e5a
RR
360struct kernel_param_ops param_ops_invbool = {
361 .set = param_set_invbool,
362 .get = param_get_invbool,
363};
364EXPORT_SYMBOL(param_ops_invbool);
365
9730b5b0 366/* We break the rule and mangle the string. */
9871728b
AB
367static int param_array(const char *name,
368 const char *val,
369 unsigned int min, unsigned int max,
370 void *elem, int elemsize,
9bbb9e5a 371 int (*set)(const char *, const struct kernel_param *kp),
3c7d76e3 372 u16 flags,
eb38a996 373 unsigned int *num)
1da177e4
LT
374{
375 int ret;
376 struct kernel_param kp;
377 char save;
378
379 /* Get the name right for errors. */
380 kp.name = name;
381 kp.arg = elem;
3c7d76e3 382 kp.flags = flags;
1da177e4 383
1da177e4
LT
384 *num = 0;
385 /* We expect a comma-separated list of values. */
386 do {
387 int len;
388
389 if (*num == max) {
390 printk(KERN_ERR "%s: can only take %i arguments\n",
391 name, max);
392 return -EINVAL;
393 }
394 len = strcspn(val, ",");
395
396 /* nul-terminate and parse */
397 save = val[len];
398 ((char *)val)[len] = '\0';
907b29eb 399 BUG_ON(!mutex_is_locked(&param_lock));
1da177e4
LT
400 ret = set(val, &kp);
401
402 if (ret != 0)
403 return ret;
404 kp.arg += elemsize;
405 val += len+1;
406 (*num)++;
407 } while (save == ',');
408
409 if (*num < min) {
410 printk(KERN_ERR "%s: needs at least %i arguments\n",
411 name, min);
412 return -EINVAL;
413 }
414 return 0;
415}
416
9bbb9e5a 417static int param_array_set(const char *val, const struct kernel_param *kp)
1da177e4 418{
22e48eaf 419 const struct kparam_array *arr = kp->arr;
31143a12 420 unsigned int temp_num;
1da177e4
LT
421
422 return param_array(kp->name, val, 1, arr->max, arr->elem,
9bbb9e5a 423 arr->elemsize, arr->ops->set, kp->flags,
3c7d76e3 424 arr->num ?: &temp_num);
1da177e4
LT
425}
426
9bbb9e5a 427static int param_array_get(char *buffer, const struct kernel_param *kp)
1da177e4
LT
428{
429 int i, off, ret;
22e48eaf 430 const struct kparam_array *arr = kp->arr;
1da177e4
LT
431 struct kernel_param p;
432
433 p = *kp;
434 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
435 if (i)
436 buffer[off++] = ',';
437 p.arg = arr->elem + arr->elemsize * i;
907b29eb 438 BUG_ON(!mutex_is_locked(&param_lock));
9bbb9e5a 439 ret = arr->ops->get(buffer + off, &p);
1da177e4
LT
440 if (ret < 0)
441 return ret;
442 off += ret;
443 }
444 buffer[off] = '\0';
445 return off;
446}
447
e6df34a4
RR
448static void param_array_free(void *arg)
449{
450 unsigned int i;
451 const struct kparam_array *arr = arg;
452
453 if (arr->ops->free)
454 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
455 arr->ops->free(arr->elem + arr->elemsize * i);
456}
457
9bbb9e5a
RR
458struct kernel_param_ops param_array_ops = {
459 .set = param_array_set,
460 .get = param_array_get,
e6df34a4 461 .free = param_array_free,
9bbb9e5a
RR
462};
463EXPORT_SYMBOL(param_array_ops);
464
465int param_set_copystring(const char *val, const struct kernel_param *kp)
1da177e4 466{
22e48eaf 467 const struct kparam_string *kps = kp->str;
1da177e4
LT
468
469 if (strlen(val)+1 > kps->maxlen) {
470 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
471 kp->name, kps->maxlen-1);
472 return -ENOSPC;
473 }
474 strcpy(kps->string, val);
475 return 0;
476}
a14fe249 477EXPORT_SYMBOL(param_set_copystring);
1da177e4 478
9bbb9e5a 479int param_get_string(char *buffer, const struct kernel_param *kp)
1da177e4 480{
22e48eaf 481 const struct kparam_string *kps = kp->str;
1da177e4
LT
482 return strlcpy(buffer, kps->string, kps->maxlen);
483}
a14fe249 484EXPORT_SYMBOL(param_get_string);
1da177e4 485
9bbb9e5a
RR
486struct kernel_param_ops param_ops_string = {
487 .set = param_set_copystring,
488 .get = param_get_string,
489};
490EXPORT_SYMBOL(param_ops_string);
491
1da177e4 492/* sysfs output in /sys/modules/XYZ/parameters/ */
350f8258
EY
493#define to_module_attr(n) container_of(n, struct module_attribute, attr)
494#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
1da177e4
LT
495
496extern struct kernel_param __start___param[], __stop___param[];
497
1da177e4
LT
498struct param_attribute
499{
500 struct module_attribute mattr;
9bbb9e5a 501 const struct kernel_param *param;
1da177e4
LT
502};
503
504struct module_param_attrs
505{
9b473de8 506 unsigned int num;
1da177e4
LT
507 struct attribute_group grp;
508 struct param_attribute attrs[0];
509};
510
ef665c1a 511#ifdef CONFIG_SYSFS
350f8258 512#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
1da177e4
LT
513
514static ssize_t param_attr_show(struct module_attribute *mattr,
4befb026 515 struct module_kobject *mk, char *buf)
1da177e4
LT
516{
517 int count;
518 struct param_attribute *attribute = to_param_attr(mattr);
519
9bbb9e5a 520 if (!attribute->param->ops->get)
1da177e4
LT
521 return -EPERM;
522
907b29eb 523 mutex_lock(&param_lock);
9bbb9e5a 524 count = attribute->param->ops->get(buf, attribute->param);
907b29eb 525 mutex_unlock(&param_lock);
1da177e4
LT
526 if (count > 0) {
527 strcat(buf, "\n");
528 ++count;
529 }
530 return count;
531}
532
533/* sysfs always hands a nul-terminated string in buf. We rely on that. */
534static ssize_t param_attr_store(struct module_attribute *mattr,
4befb026 535 struct module_kobject *km,
1da177e4
LT
536 const char *buf, size_t len)
537{
538 int err;
539 struct param_attribute *attribute = to_param_attr(mattr);
540
9bbb9e5a 541 if (!attribute->param->ops->set)
1da177e4
LT
542 return -EPERM;
543
907b29eb 544 mutex_lock(&param_lock);
9bbb9e5a 545 err = attribute->param->ops->set(buf, attribute->param);
907b29eb 546 mutex_unlock(&param_lock);
1da177e4
LT
547 if (!err)
548 return len;
549 return err;
550}
ef665c1a 551#endif
1da177e4
LT
552
553#ifdef CONFIG_MODULES
554#define __modinit
555#else
556#define __modinit __init
557#endif
558
ef665c1a 559#ifdef CONFIG_SYSFS
907b29eb
RR
560void __kernel_param_lock(void)
561{
562 mutex_lock(&param_lock);
563}
564EXPORT_SYMBOL(__kernel_param_lock);
565
566void __kernel_param_unlock(void)
567{
568 mutex_unlock(&param_lock);
569}
570EXPORT_SYMBOL(__kernel_param_unlock);
571
1da177e4 572/*
9b473de8
RR
573 * add_sysfs_param - add a parameter to sysfs
574 * @mk: struct module_kobject
575 * @kparam: the actual parameter definition to add to sysfs
576 * @name: name of parameter
1da177e4 577 *
9b473de8
RR
578 * Create a kobject if for a (per-module) parameter if mp NULL, and
579 * create file in sysfs. Returns an error on out of memory. Always cleans up
580 * if there's an error.
1da177e4 581 */
9b473de8 582static __modinit int add_sysfs_param(struct module_kobject *mk,
9bbb9e5a 583 const struct kernel_param *kp,
9b473de8 584 const char *name)
1da177e4 585{
9b473de8
RR
586 struct module_param_attrs *new;
587 struct attribute **attrs;
588 int err, num;
589
590 /* We don't bother calling this with invisible parameters. */
591 BUG_ON(!kp->perm);
592
593 if (!mk->mp) {
594 num = 0;
595 attrs = NULL;
596 } else {
597 num = mk->mp->num;
598 attrs = mk->mp->grp.attrs;
1da177e4
LT
599 }
600
9b473de8
RR
601 /* Enlarge. */
602 new = krealloc(mk->mp,
603 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
604 GFP_KERNEL);
605 if (!new) {
606 kfree(mk->mp);
607 err = -ENOMEM;
608 goto fail;
609 }
610 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
611 if (!attrs) {
612 err = -ENOMEM;
613 goto fail_free_new;
614 }
1da177e4 615
9b473de8
RR
616 /* Sysfs wants everything zeroed. */
617 memset(new, 0, sizeof(*new));
618 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
619 memset(&attrs[num], 0, sizeof(attrs[num]));
620 new->grp.name = "parameters";
621 new->grp.attrs = attrs;
622
623 /* Tack new one on the end. */
a07e4156 624 sysfs_attr_init(&new->attrs[num].mattr.attr);
9b473de8
RR
625 new->attrs[num].param = kp;
626 new->attrs[num].mattr.show = param_attr_show;
627 new->attrs[num].mattr.store = param_attr_store;
628 new->attrs[num].mattr.attr.name = (char *)name;
629 new->attrs[num].mattr.attr.mode = kp->perm;
630 new->num = num+1;
631
632 /* Fix up all the pointers, since krealloc can move us */
633 for (num = 0; num < new->num; num++)
634 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
635 new->grp.attrs[num] = NULL;
636
637 mk->mp = new;
638 return 0;
1da177e4 639
9b473de8
RR
640fail_free_new:
641 kfree(new);
642fail:
643 mk->mp = NULL;
644 return err;
645}
1da177e4 646
d2441183 647#ifdef CONFIG_MODULES
9b473de8
RR
648static void free_module_param_attrs(struct module_kobject *mk)
649{
650 kfree(mk->mp->grp.attrs);
651 kfree(mk->mp);
652 mk->mp = NULL;
1da177e4
LT
653}
654
1da177e4
LT
655/*
656 * module_param_sysfs_setup - setup sysfs support for one module
657 * @mod: module
658 * @kparam: module parameters (array)
659 * @num_params: number of module parameters
660 *
9b473de8
RR
661 * Adds sysfs entries for module parameters under
662 * /sys/module/[mod->name]/parameters/
1da177e4
LT
663 */
664int module_param_sysfs_setup(struct module *mod,
9bbb9e5a 665 const struct kernel_param *kparam,
1da177e4
LT
666 unsigned int num_params)
667{
9b473de8
RR
668 int i, err;
669 bool params = false;
670
671 for (i = 0; i < num_params; i++) {
672 if (kparam[i].perm == 0)
673 continue;
674 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
675 if (err)
676 return err;
677 params = true;
678 }
1da177e4 679
9b473de8
RR
680 if (!params)
681 return 0;
1da177e4 682
9b473de8
RR
683 /* Create the param group. */
684 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
685 if (err)
686 free_module_param_attrs(&mod->mkobj);
687 return err;
1da177e4
LT
688}
689
690/*
691 * module_param_sysfs_remove - remove sysfs support for one module
692 * @mod: module
693 *
694 * Remove sysfs entries for module parameters and the corresponding
695 * kobject.
696 */
697void module_param_sysfs_remove(struct module *mod)
698{
9b473de8
RR
699 if (mod->mkobj.mp) {
700 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
1da177e4
LT
701 /* We are positive that no one is using any param
702 * attrs at this point. Deallocate immediately. */
9b473de8 703 free_module_param_attrs(&mod->mkobj);
1da177e4
LT
704 }
705}
706#endif
707
e180a6b7
RR
708void destroy_params(const struct kernel_param *params, unsigned num)
709{
e6df34a4
RR
710 unsigned int i;
711
712 for (i = 0; i < num; i++)
713 if (params[i].ops->free)
714 params[i].ops->free(params[i].arg);
e180a6b7
RR
715}
716
e94965ed 717static struct module_kobject * __init locate_module_kobject(const char *name)
1da177e4
LT
718{
719 struct module_kobject *mk;
9b473de8
RR
720 struct kobject *kobj;
721 int err;
1da177e4 722
9b473de8
RR
723 kobj = kset_find_obj(module_kset, name);
724 if (kobj) {
9b473de8 725 mk = to_module_kobject(kobj);
9b473de8
RR
726 } else {
727 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
728 BUG_ON(!mk);
729
730 mk->mod = THIS_MODULE;
731 mk->kobj.kset = module_kset;
732 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
733 "%s", name);
88bfa324
KS
734#ifdef CONFIG_MODULES
735 if (!err)
736 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
737#endif
9b473de8
RR
738 if (err) {
739 kobject_put(&mk->kobj);
e94965ed
DT
740 printk(KERN_ERR
741 "Module '%s' failed add to sysfs, error number %d\n",
742 name, err);
743 printk(KERN_ERR
744 "The system will be unstable now.\n");
745 return NULL;
9b473de8 746 }
e94965ed
DT
747
748 /* So that we hold reference in both cases. */
9b473de8 749 kobject_get(&mk->kobj);
74c5b597 750 }
9b473de8 751
e94965ed
DT
752 return mk;
753}
754
755static void __init kernel_add_sysfs_param(const char *name,
756 struct kernel_param *kparam,
757 unsigned int name_skip)
758{
759 struct module_kobject *mk;
760 int err;
761
762 mk = locate_module_kobject(name);
763 if (!mk)
764 return;
765
766 /* We need to remove old parameters before adding more. */
767 if (mk->mp)
768 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
769
9b473de8
RR
770 /* These should not fail at boot. */
771 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
772 BUG_ON(err);
773 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
774 BUG_ON(err);
f30c53a8 775 kobject_uevent(&mk->kobj, KOBJ_ADD);
9b473de8 776 kobject_put(&mk->kobj);
1da177e4
LT
777}
778
779/*
780 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
781 *
782 * Add module_parameters to sysfs for "modules" built into the kernel.
783 *
784 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
785 * "parameter" name is stored behind a dot in kernel_param->name. So,
786 * extract the "module" name for all built-in kernel_param-eters,
9b473de8 787 * and for all who have the same, call kernel_add_sysfs_param.
1da177e4
LT
788 */
789static void __init param_sysfs_builtin(void)
790{
9b473de8
RR
791 struct kernel_param *kp;
792 unsigned int name_len;
793 char modname[MODULE_NAME_LEN];
1da177e4 794
9b473de8 795 for (kp = __start___param; kp < __stop___param; kp++) {
1da177e4
LT
796 char *dot;
797
9b473de8
RR
798 if (kp->perm == 0)
799 continue;
1da177e4 800
730b69d2 801 dot = strchr(kp->name, '.');
1da177e4 802 if (!dot) {
67e67cea
RR
803 /* This happens for core_param() */
804 strcpy(modname, "kernel");
805 name_len = 0;
806 } else {
807 name_len = dot - kp->name + 1;
808 strlcpy(modname, kp->name, name_len);
1da177e4 809 }
67e67cea 810 kernel_add_sysfs_param(modname, kp, name_len);
1da177e4 811 }
1da177e4
LT
812}
813
e94965ed 814ssize_t __modver_version_show(struct module_attribute *mattr,
4befb026 815 struct module_kobject *mk, char *buf)
e94965ed
DT
816{
817 struct module_version_attribute *vattr =
818 container_of(mattr, struct module_version_attribute, mattr);
819
820 return sprintf(buf, "%s\n", vattr->version);
821}
822
b4bc8428
DT
823extern const struct module_version_attribute *__start___modver[];
824extern const struct module_version_attribute *__stop___modver[];
e94965ed
DT
825
826static void __init version_sysfs_builtin(void)
827{
b4bc8428 828 const struct module_version_attribute **p;
e94965ed
DT
829 struct module_kobject *mk;
830 int err;
831
b4bc8428
DT
832 for (p = __start___modver; p < __stop___modver; p++) {
833 const struct module_version_attribute *vattr = *p;
834
e94965ed
DT
835 mk = locate_module_kobject(vattr->module_name);
836 if (mk) {
837 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
838 kobject_uevent(&mk->kobj, KOBJ_ADD);
839 kobject_put(&mk->kobj);
840 }
841 }
842}
1da177e4
LT
843
844/* module-related sysfs stuff */
1da177e4 845
1da177e4
LT
846static ssize_t module_attr_show(struct kobject *kobj,
847 struct attribute *attr,
848 char *buf)
849{
850 struct module_attribute *attribute;
851 struct module_kobject *mk;
852 int ret;
853
854 attribute = to_module_attr(attr);
855 mk = to_module_kobject(kobj);
856
857 if (!attribute->show)
70f2817a 858 return -EIO;
1da177e4 859
4befb026 860 ret = attribute->show(attribute, mk, buf);
1da177e4 861
1da177e4
LT
862 return ret;
863}
864
865static ssize_t module_attr_store(struct kobject *kobj,
866 struct attribute *attr,
867 const char *buf, size_t len)
868{
869 struct module_attribute *attribute;
870 struct module_kobject *mk;
871 int ret;
872
873 attribute = to_module_attr(attr);
874 mk = to_module_kobject(kobj);
875
876 if (!attribute->store)
70f2817a 877 return -EIO;
1da177e4 878
4befb026 879 ret = attribute->store(attribute, mk, buf, len);
1da177e4 880
1da177e4
LT
881 return ret;
882}
883
52cf25d0 884static const struct sysfs_ops module_sysfs_ops = {
1da177e4
LT
885 .show = module_attr_show,
886 .store = module_attr_store,
887};
888
270a6c4c
KS
889static int uevent_filter(struct kset *kset, struct kobject *kobj)
890{
891 struct kobj_type *ktype = get_ktype(kobj);
892
893 if (ktype == &module_ktype)
894 return 1;
895 return 0;
896}
897
9cd43611 898static const struct kset_uevent_ops module_uevent_ops = {
270a6c4c
KS
899 .filter = uevent_filter,
900};
901
7405c1e1 902struct kset *module_kset;
823bccfc 903int module_sysfs_initialized;
1da177e4 904
7405c1e1 905struct kobj_type module_ktype = {
1da177e4
LT
906 .sysfs_ops = &module_sysfs_ops,
907};
908
1da177e4
LT
909/*
910 * param_sysfs_init - wrapper for built-in params support
911 */
912static int __init param_sysfs_init(void)
913{
7405c1e1
GKH
914 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
915 if (!module_kset) {
916 printk(KERN_WARNING "%s (%d): error creating kset\n",
917 __FILE__, __LINE__);
918 return -ENOMEM;
d8c7649e 919 }
823bccfc 920 module_sysfs_initialized = 1;
1da177e4 921
e94965ed 922 version_sysfs_builtin();
1da177e4
LT
923 param_sysfs_builtin();
924
925 return 0;
926}
d10be6d1 927subsys_initcall(param_sysfs_init);
1da177e4 928
7405c1e1 929#endif /* CONFIG_SYSFS */