module_param: remove support for bool parameters which are really int.
[GitHub/mt8127/android_kernel_alcatel_ttab.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*/
1da177e4
LT
18#include <linux/kernel.h>
19#include <linux/string.h>
20#include <linux/errno.h>
21#include <linux/module.h>
22#include <linux/device.h>
23#include <linux/err.h>
4e57b681 24#include <linux/slab.h>
26d052bf 25#include <linux/ctype.h>
1da177e4 26
907b29eb
RR
27/* Protects all parameters, and incidentally kmalloced_param list. */
28static DEFINE_MUTEX(param_lock);
29
a1054322
RR
30/* This just allows us to keep track of which parameters are kmalloced. */
31struct kmalloced_param {
32 struct list_head list;
33 char val[];
34};
a1054322
RR
35static LIST_HEAD(kmalloced_params);
36
37static void *kmalloc_parameter(unsigned int size)
38{
39 struct kmalloced_param *p;
40
41 p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
42 if (!p)
43 return NULL;
44
a1054322 45 list_add(&p->list, &kmalloced_params);
a1054322
RR
46 return p->val;
47}
48
49/* Does nothing if parameter wasn't kmalloced above. */
50static void maybe_kfree_parameter(void *param)
51{
52 struct kmalloced_param *p;
53
a1054322
RR
54 list_for_each_entry(p, &kmalloced_params, list) {
55 if (p->val == param) {
56 list_del(&p->list);
57 kfree(p);
58 break;
59 }
60 }
a1054322
RR
61}
62
b1e4d20c 63static char dash2underscore(char c)
1da177e4
LT
64{
65 if (c == '-')
66 return '_';
67 return c;
68}
69
b1e4d20c 70bool parameqn(const char *a, const char *b, size_t n)
1da177e4 71{
b1e4d20c
MS
72 size_t i;
73
74 for (i = 0; i < n; i++) {
75 if (dash2underscore(a[i]) != dash2underscore(b[i]))
76 return false;
77 }
78 return true;
79}
80
81bool parameq(const char *a, const char *b)
82{
83 return parameqn(a, b, strlen(a)+1);
1da177e4
LT
84}
85
86static int parse_one(char *param,
87 char *val,
914dcaa8 88 const struct kernel_param *params,
1da177e4
LT
89 unsigned num_params,
90 int (*handle_unknown)(char *param, char *val))
91{
92 unsigned int i;
907b29eb 93 int err;
1da177e4
LT
94
95 /* Find parameter */
96 for (i = 0; i < num_params; i++) {
97 if (parameq(param, params[i].name)) {
25985edc 98 /* No one handled NULL, so do it here. */
10f296cb
DY
99 if (!val && params[i].ops->set != param_set_bool
100 && params[i].ops->set != param_set_bint)
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
LT
299{
300 /* No equals means "set"... */
301 if (!val) val = "1";
302
303 /* One of =[yYnN01] */
8b825281 304 return strtobool(val, kp->arg);
1da177e4 305}
a14fe249 306EXPORT_SYMBOL(param_set_bool);
1da177e4 307
9bbb9e5a 308int param_get_bool(char *buffer, const struct kernel_param *kp)
1da177e4
LT
309{
310 /* Y and N chosen as being relatively non-coder friendly */
8b825281 311 return sprintf(buffer, "%c", *(bool *)kp->arg ? 'Y' : 'N');
1da177e4 312}
a14fe249 313EXPORT_SYMBOL(param_get_bool);
1da177e4 314
9bbb9e5a
RR
315struct kernel_param_ops param_ops_bool = {
316 .set = param_set_bool,
317 .get = param_get_bool,
318};
319EXPORT_SYMBOL(param_ops_bool);
320
fddd5201 321/* This one must be bool. */
9bbb9e5a 322int param_set_invbool(const char *val, const struct kernel_param *kp)
1da177e4 323{
fddd5201
RR
324 int ret;
325 bool boolval;
22e48eaf 326 struct kernel_param dummy;
1da177e4 327
22e48eaf 328 dummy.arg = &boolval;
1da177e4
LT
329 ret = param_set_bool(val, &dummy);
330 if (ret == 0)
9a71af2c 331 *(bool *)kp->arg = !boolval;
1da177e4
LT
332 return ret;
333}
a14fe249 334EXPORT_SYMBOL(param_set_invbool);
1da177e4 335
9bbb9e5a 336int param_get_invbool(char *buffer, const struct kernel_param *kp)
1da177e4 337{
9a71af2c 338 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
1da177e4 339}
a14fe249 340EXPORT_SYMBOL(param_get_invbool);
1da177e4 341
9bbb9e5a
RR
342struct kernel_param_ops param_ops_invbool = {
343 .set = param_set_invbool,
344 .get = param_get_invbool,
345};
346EXPORT_SYMBOL(param_ops_invbool);
347
69116f27
RR
348int param_set_bint(const char *val, const struct kernel_param *kp)
349{
350 struct kernel_param boolkp;
351 bool v;
352 int ret;
353
354 /* Match bool exactly, by re-using it. */
355 boolkp = *kp;
356 boolkp.arg = &v;
69116f27
RR
357
358 ret = param_set_bool(val, &boolkp);
359 if (ret == 0)
360 *(int *)kp->arg = v;
361 return ret;
362}
363EXPORT_SYMBOL(param_set_bint);
364
365struct kernel_param_ops param_ops_bint = {
366 .set = param_set_bint,
367 .get = param_get_int,
368};
369EXPORT_SYMBOL(param_ops_bint);
370
9730b5b0 371/* We break the rule and mangle the string. */
9871728b
AB
372static int param_array(const char *name,
373 const char *val,
374 unsigned int min, unsigned int max,
375 void *elem, int elemsize,
9bbb9e5a 376 int (*set)(const char *, const struct kernel_param *kp),
3c7d76e3 377 u16 flags,
eb38a996 378 unsigned int *num)
1da177e4
LT
379{
380 int ret;
381 struct kernel_param kp;
382 char save;
383
384 /* Get the name right for errors. */
385 kp.name = name;
386 kp.arg = elem;
3c7d76e3 387 kp.flags = flags;
1da177e4 388
1da177e4
LT
389 *num = 0;
390 /* We expect a comma-separated list of values. */
391 do {
392 int len;
393
394 if (*num == max) {
395 printk(KERN_ERR "%s: can only take %i arguments\n",
396 name, max);
397 return -EINVAL;
398 }
399 len = strcspn(val, ",");
400
401 /* nul-terminate and parse */
402 save = val[len];
403 ((char *)val)[len] = '\0';
907b29eb 404 BUG_ON(!mutex_is_locked(&param_lock));
1da177e4
LT
405 ret = set(val, &kp);
406
407 if (ret != 0)
408 return ret;
409 kp.arg += elemsize;
410 val += len+1;
411 (*num)++;
412 } while (save == ',');
413
414 if (*num < min) {
415 printk(KERN_ERR "%s: needs at least %i arguments\n",
416 name, min);
417 return -EINVAL;
418 }
419 return 0;
420}
421
9bbb9e5a 422static int param_array_set(const char *val, const struct kernel_param *kp)
1da177e4 423{
22e48eaf 424 const struct kparam_array *arr = kp->arr;
31143a12 425 unsigned int temp_num;
1da177e4
LT
426
427 return param_array(kp->name, val, 1, arr->max, arr->elem,
9bbb9e5a 428 arr->elemsize, arr->ops->set, kp->flags,
3c7d76e3 429 arr->num ?: &temp_num);
1da177e4
LT
430}
431
9bbb9e5a 432static int param_array_get(char *buffer, const struct kernel_param *kp)
1da177e4
LT
433{
434 int i, off, ret;
22e48eaf 435 const struct kparam_array *arr = kp->arr;
1da177e4
LT
436 struct kernel_param p;
437
438 p = *kp;
439 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
440 if (i)
441 buffer[off++] = ',';
442 p.arg = arr->elem + arr->elemsize * i;
907b29eb 443 BUG_ON(!mutex_is_locked(&param_lock));
9bbb9e5a 444 ret = arr->ops->get(buffer + off, &p);
1da177e4
LT
445 if (ret < 0)
446 return ret;
447 off += ret;
448 }
449 buffer[off] = '\0';
450 return off;
451}
452
e6df34a4
RR
453static void param_array_free(void *arg)
454{
455 unsigned int i;
456 const struct kparam_array *arr = arg;
457
458 if (arr->ops->free)
459 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
460 arr->ops->free(arr->elem + arr->elemsize * i);
461}
462
9bbb9e5a
RR
463struct kernel_param_ops param_array_ops = {
464 .set = param_array_set,
465 .get = param_array_get,
e6df34a4 466 .free = param_array_free,
9bbb9e5a
RR
467};
468EXPORT_SYMBOL(param_array_ops);
469
470int param_set_copystring(const char *val, const struct kernel_param *kp)
1da177e4 471{
22e48eaf 472 const struct kparam_string *kps = kp->str;
1da177e4
LT
473
474 if (strlen(val)+1 > kps->maxlen) {
475 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
476 kp->name, kps->maxlen-1);
477 return -ENOSPC;
478 }
479 strcpy(kps->string, val);
480 return 0;
481}
a14fe249 482EXPORT_SYMBOL(param_set_copystring);
1da177e4 483
9bbb9e5a 484int param_get_string(char *buffer, const struct kernel_param *kp)
1da177e4 485{
22e48eaf 486 const struct kparam_string *kps = kp->str;
1da177e4
LT
487 return strlcpy(buffer, kps->string, kps->maxlen);
488}
a14fe249 489EXPORT_SYMBOL(param_get_string);
1da177e4 490
9bbb9e5a
RR
491struct kernel_param_ops param_ops_string = {
492 .set = param_set_copystring,
493 .get = param_get_string,
494};
495EXPORT_SYMBOL(param_ops_string);
496
1da177e4 497/* sysfs output in /sys/modules/XYZ/parameters/ */
350f8258
EY
498#define to_module_attr(n) container_of(n, struct module_attribute, attr)
499#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
1da177e4
LT
500
501extern struct kernel_param __start___param[], __stop___param[];
502
1da177e4
LT
503struct param_attribute
504{
505 struct module_attribute mattr;
9bbb9e5a 506 const struct kernel_param *param;
1da177e4
LT
507};
508
509struct module_param_attrs
510{
9b473de8 511 unsigned int num;
1da177e4
LT
512 struct attribute_group grp;
513 struct param_attribute attrs[0];
514};
515
ef665c1a 516#ifdef CONFIG_SYSFS
350f8258 517#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
1da177e4
LT
518
519static ssize_t param_attr_show(struct module_attribute *mattr,
4befb026 520 struct module_kobject *mk, char *buf)
1da177e4
LT
521{
522 int count;
523 struct param_attribute *attribute = to_param_attr(mattr);
524
9bbb9e5a 525 if (!attribute->param->ops->get)
1da177e4
LT
526 return -EPERM;
527
907b29eb 528 mutex_lock(&param_lock);
9bbb9e5a 529 count = attribute->param->ops->get(buf, attribute->param);
907b29eb 530 mutex_unlock(&param_lock);
1da177e4
LT
531 if (count > 0) {
532 strcat(buf, "\n");
533 ++count;
534 }
535 return count;
536}
537
538/* sysfs always hands a nul-terminated string in buf. We rely on that. */
539static ssize_t param_attr_store(struct module_attribute *mattr,
4befb026 540 struct module_kobject *km,
1da177e4
LT
541 const char *buf, size_t len)
542{
543 int err;
544 struct param_attribute *attribute = to_param_attr(mattr);
545
9bbb9e5a 546 if (!attribute->param->ops->set)
1da177e4
LT
547 return -EPERM;
548
907b29eb 549 mutex_lock(&param_lock);
9bbb9e5a 550 err = attribute->param->ops->set(buf, attribute->param);
907b29eb 551 mutex_unlock(&param_lock);
1da177e4
LT
552 if (!err)
553 return len;
554 return err;
555}
ef665c1a 556#endif
1da177e4
LT
557
558#ifdef CONFIG_MODULES
559#define __modinit
560#else
561#define __modinit __init
562#endif
563
ef665c1a 564#ifdef CONFIG_SYSFS
907b29eb
RR
565void __kernel_param_lock(void)
566{
567 mutex_lock(&param_lock);
568}
569EXPORT_SYMBOL(__kernel_param_lock);
570
571void __kernel_param_unlock(void)
572{
573 mutex_unlock(&param_lock);
574}
575EXPORT_SYMBOL(__kernel_param_unlock);
576
1da177e4 577/*
9b473de8
RR
578 * add_sysfs_param - add a parameter to sysfs
579 * @mk: struct module_kobject
580 * @kparam: the actual parameter definition to add to sysfs
581 * @name: name of parameter
1da177e4 582 *
9b473de8
RR
583 * Create a kobject if for a (per-module) parameter if mp NULL, and
584 * create file in sysfs. Returns an error on out of memory. Always cleans up
585 * if there's an error.
1da177e4 586 */
9b473de8 587static __modinit int add_sysfs_param(struct module_kobject *mk,
9bbb9e5a 588 const struct kernel_param *kp,
9b473de8 589 const char *name)
1da177e4 590{
9b473de8
RR
591 struct module_param_attrs *new;
592 struct attribute **attrs;
593 int err, num;
594
595 /* We don't bother calling this with invisible parameters. */
596 BUG_ON(!kp->perm);
597
598 if (!mk->mp) {
599 num = 0;
600 attrs = NULL;
601 } else {
602 num = mk->mp->num;
603 attrs = mk->mp->grp.attrs;
1da177e4
LT
604 }
605
9b473de8
RR
606 /* Enlarge. */
607 new = krealloc(mk->mp,
608 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
609 GFP_KERNEL);
610 if (!new) {
611 kfree(mk->mp);
612 err = -ENOMEM;
613 goto fail;
614 }
615 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
616 if (!attrs) {
617 err = -ENOMEM;
618 goto fail_free_new;
619 }
1da177e4 620
9b473de8
RR
621 /* Sysfs wants everything zeroed. */
622 memset(new, 0, sizeof(*new));
623 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
624 memset(&attrs[num], 0, sizeof(attrs[num]));
625 new->grp.name = "parameters";
626 new->grp.attrs = attrs;
627
628 /* Tack new one on the end. */
a07e4156 629 sysfs_attr_init(&new->attrs[num].mattr.attr);
9b473de8
RR
630 new->attrs[num].param = kp;
631 new->attrs[num].mattr.show = param_attr_show;
632 new->attrs[num].mattr.store = param_attr_store;
633 new->attrs[num].mattr.attr.name = (char *)name;
634 new->attrs[num].mattr.attr.mode = kp->perm;
635 new->num = num+1;
636
637 /* Fix up all the pointers, since krealloc can move us */
638 for (num = 0; num < new->num; num++)
639 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
640 new->grp.attrs[num] = NULL;
641
642 mk->mp = new;
643 return 0;
1da177e4 644
9b473de8
RR
645fail_free_new:
646 kfree(new);
647fail:
648 mk->mp = NULL;
649 return err;
650}
1da177e4 651
d2441183 652#ifdef CONFIG_MODULES
9b473de8
RR
653static void free_module_param_attrs(struct module_kobject *mk)
654{
655 kfree(mk->mp->grp.attrs);
656 kfree(mk->mp);
657 mk->mp = NULL;
1da177e4
LT
658}
659
1da177e4
LT
660/*
661 * module_param_sysfs_setup - setup sysfs support for one module
662 * @mod: module
663 * @kparam: module parameters (array)
664 * @num_params: number of module parameters
665 *
9b473de8
RR
666 * Adds sysfs entries for module parameters under
667 * /sys/module/[mod->name]/parameters/
1da177e4
LT
668 */
669int module_param_sysfs_setup(struct module *mod,
9bbb9e5a 670 const struct kernel_param *kparam,
1da177e4
LT
671 unsigned int num_params)
672{
9b473de8
RR
673 int i, err;
674 bool params = false;
675
676 for (i = 0; i < num_params; i++) {
677 if (kparam[i].perm == 0)
678 continue;
679 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
680 if (err)
681 return err;
682 params = true;
683 }
1da177e4 684
9b473de8
RR
685 if (!params)
686 return 0;
1da177e4 687
9b473de8
RR
688 /* Create the param group. */
689 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
690 if (err)
691 free_module_param_attrs(&mod->mkobj);
692 return err;
1da177e4
LT
693}
694
695/*
696 * module_param_sysfs_remove - remove sysfs support for one module
697 * @mod: module
698 *
699 * Remove sysfs entries for module parameters and the corresponding
700 * kobject.
701 */
702void module_param_sysfs_remove(struct module *mod)
703{
9b473de8
RR
704 if (mod->mkobj.mp) {
705 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
1da177e4
LT
706 /* We are positive that no one is using any param
707 * attrs at this point. Deallocate immediately. */
9b473de8 708 free_module_param_attrs(&mod->mkobj);
1da177e4
LT
709 }
710}
711#endif
712
e180a6b7
RR
713void destroy_params(const struct kernel_param *params, unsigned num)
714{
e6df34a4
RR
715 unsigned int i;
716
717 for (i = 0; i < num; i++)
718 if (params[i].ops->free)
719 params[i].ops->free(params[i].arg);
e180a6b7
RR
720}
721
e94965ed 722static struct module_kobject * __init locate_module_kobject(const char *name)
1da177e4
LT
723{
724 struct module_kobject *mk;
9b473de8
RR
725 struct kobject *kobj;
726 int err;
1da177e4 727
9b473de8
RR
728 kobj = kset_find_obj(module_kset, name);
729 if (kobj) {
9b473de8 730 mk = to_module_kobject(kobj);
9b473de8
RR
731 } else {
732 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
733 BUG_ON(!mk);
734
735 mk->mod = THIS_MODULE;
736 mk->kobj.kset = module_kset;
737 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
738 "%s", name);
88bfa324
KS
739#ifdef CONFIG_MODULES
740 if (!err)
741 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
742#endif
9b473de8
RR
743 if (err) {
744 kobject_put(&mk->kobj);
e94965ed
DT
745 printk(KERN_ERR
746 "Module '%s' failed add to sysfs, error number %d\n",
747 name, err);
748 printk(KERN_ERR
749 "The system will be unstable now.\n");
750 return NULL;
9b473de8 751 }
e94965ed
DT
752
753 /* So that we hold reference in both cases. */
9b473de8 754 kobject_get(&mk->kobj);
74c5b597 755 }
9b473de8 756
e94965ed
DT
757 return mk;
758}
759
760static void __init kernel_add_sysfs_param(const char *name,
761 struct kernel_param *kparam,
762 unsigned int name_skip)
763{
764 struct module_kobject *mk;
765 int err;
766
767 mk = locate_module_kobject(name);
768 if (!mk)
769 return;
770
771 /* We need to remove old parameters before adding more. */
772 if (mk->mp)
773 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
774
9b473de8
RR
775 /* These should not fail at boot. */
776 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
777 BUG_ON(err);
778 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
779 BUG_ON(err);
f30c53a8 780 kobject_uevent(&mk->kobj, KOBJ_ADD);
9b473de8 781 kobject_put(&mk->kobj);
1da177e4
LT
782}
783
784/*
785 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
786 *
787 * Add module_parameters to sysfs for "modules" built into the kernel.
788 *
789 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
790 * "parameter" name is stored behind a dot in kernel_param->name. So,
791 * extract the "module" name for all built-in kernel_param-eters,
9b473de8 792 * and for all who have the same, call kernel_add_sysfs_param.
1da177e4
LT
793 */
794static void __init param_sysfs_builtin(void)
795{
9b473de8
RR
796 struct kernel_param *kp;
797 unsigned int name_len;
798 char modname[MODULE_NAME_LEN];
1da177e4 799
9b473de8 800 for (kp = __start___param; kp < __stop___param; kp++) {
1da177e4
LT
801 char *dot;
802
9b473de8
RR
803 if (kp->perm == 0)
804 continue;
1da177e4 805
730b69d2 806 dot = strchr(kp->name, '.');
1da177e4 807 if (!dot) {
67e67cea
RR
808 /* This happens for core_param() */
809 strcpy(modname, "kernel");
810 name_len = 0;
811 } else {
812 name_len = dot - kp->name + 1;
813 strlcpy(modname, kp->name, name_len);
1da177e4 814 }
67e67cea 815 kernel_add_sysfs_param(modname, kp, name_len);
1da177e4 816 }
1da177e4
LT
817}
818
e94965ed 819ssize_t __modver_version_show(struct module_attribute *mattr,
4befb026 820 struct module_kobject *mk, char *buf)
e94965ed
DT
821{
822 struct module_version_attribute *vattr =
823 container_of(mattr, struct module_version_attribute, mattr);
824
825 return sprintf(buf, "%s\n", vattr->version);
826}
827
b4bc8428
DT
828extern const struct module_version_attribute *__start___modver[];
829extern const struct module_version_attribute *__stop___modver[];
e94965ed
DT
830
831static void __init version_sysfs_builtin(void)
832{
b4bc8428 833 const struct module_version_attribute **p;
e94965ed
DT
834 struct module_kobject *mk;
835 int err;
836
b4bc8428
DT
837 for (p = __start___modver; p < __stop___modver; p++) {
838 const struct module_version_attribute *vattr = *p;
839
e94965ed
DT
840 mk = locate_module_kobject(vattr->module_name);
841 if (mk) {
842 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
843 kobject_uevent(&mk->kobj, KOBJ_ADD);
844 kobject_put(&mk->kobj);
845 }
846 }
847}
1da177e4
LT
848
849/* module-related sysfs stuff */
1da177e4 850
1da177e4
LT
851static ssize_t module_attr_show(struct kobject *kobj,
852 struct attribute *attr,
853 char *buf)
854{
855 struct module_attribute *attribute;
856 struct module_kobject *mk;
857 int ret;
858
859 attribute = to_module_attr(attr);
860 mk = to_module_kobject(kobj);
861
862 if (!attribute->show)
70f2817a 863 return -EIO;
1da177e4 864
4befb026 865 ret = attribute->show(attribute, mk, buf);
1da177e4 866
1da177e4
LT
867 return ret;
868}
869
870static ssize_t module_attr_store(struct kobject *kobj,
871 struct attribute *attr,
872 const char *buf, size_t len)
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->store)
70f2817a 882 return -EIO;
1da177e4 883
4befb026 884 ret = attribute->store(attribute, mk, buf, len);
1da177e4 885
1da177e4
LT
886 return ret;
887}
888
52cf25d0 889static const struct sysfs_ops module_sysfs_ops = {
1da177e4
LT
890 .show = module_attr_show,
891 .store = module_attr_store,
892};
893
270a6c4c
KS
894static int uevent_filter(struct kset *kset, struct kobject *kobj)
895{
896 struct kobj_type *ktype = get_ktype(kobj);
897
898 if (ktype == &module_ktype)
899 return 1;
900 return 0;
901}
902
9cd43611 903static const struct kset_uevent_ops module_uevent_ops = {
270a6c4c
KS
904 .filter = uevent_filter,
905};
906
7405c1e1 907struct kset *module_kset;
823bccfc 908int module_sysfs_initialized;
1da177e4 909
7405c1e1 910struct kobj_type module_ktype = {
1da177e4
LT
911 .sysfs_ops = &module_sysfs_ops,
912};
913
1da177e4
LT
914/*
915 * param_sysfs_init - wrapper for built-in params support
916 */
917static int __init param_sysfs_init(void)
918{
7405c1e1
GKH
919 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
920 if (!module_kset) {
921 printk(KERN_WARNING "%s (%d): error creating kset\n",
922 __FILE__, __LINE__);
923 return -ENOMEM;
d8c7649e 924 }
823bccfc 925 module_sysfs_initialized = 1;
1da177e4 926
e94965ed 927 version_sysfs_builtin();
1da177e4
LT
928 param_sysfs_builtin();
929
930 return 0;
931}
d10be6d1 932subsys_initcall(param_sysfs_init);
1da177e4 933
7405c1e1 934#endif /* CONFIG_SYSFS */