ASoC: dapm: Make sure all dapm contexts are updated
[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,
9fb48c74 88 const char *doing,
914dcaa8 89 const struct kernel_param *params,
1da177e4 90 unsigned num_params,
026cee00
PM
91 s16 min_level,
92 s16 max_level,
9fb48c74
JC
93 int (*handle_unknown)(char *param, char *val,
94 const char *doing))
1da177e4
LT
95{
96 unsigned int i;
907b29eb 97 int err;
1da177e4
LT
98
99 /* Find parameter */
100 for (i = 0; i < num_params; i++) {
101 if (parameq(param, params[i].name)) {
026cee00
PM
102 if (params[i].level < min_level
103 || params[i].level > max_level)
104 return 0;
25985edc 105 /* No one handled NULL, so do it here. */
10f296cb
DY
106 if (!val && params[i].ops->set != param_set_bool
107 && params[i].ops->set != param_set_bint)
2e9fb995 108 return -EINVAL;
9fb48c74
JC
109 pr_debug("handling %s with %p\n", param,
110 params[i].ops->set);
907b29eb
RR
111 mutex_lock(&param_lock);
112 err = params[i].ops->set(val, &params[i]);
113 mutex_unlock(&param_lock);
114 return err;
1da177e4
LT
115 }
116 }
117
118 if (handle_unknown) {
9fb48c74
JC
119 pr_debug("doing %s: %s='%s'\n", doing, param, val);
120 return handle_unknown(param, val, doing);
1da177e4
LT
121 }
122
9fb48c74 123 pr_debug("Unknown argument '%s'\n", param);
1da177e4
LT
124 return -ENOENT;
125}
126
127/* You can use " around spaces, but can't escape ". */
128/* Hyphens and underscores equivalent in parameter names. */
129static char *next_arg(char *args, char **param, char **val)
130{
131 unsigned int i, equals = 0;
132 int in_quote = 0, quoted = 0;
133 char *next;
134
1da177e4
LT
135 if (*args == '"') {
136 args++;
137 in_quote = 1;
138 quoted = 1;
139 }
140
141 for (i = 0; args[i]; i++) {
26d052bf 142 if (isspace(args[i]) && !in_quote)
1da177e4
LT
143 break;
144 if (equals == 0) {
145 if (args[i] == '=')
146 equals = i;
147 }
148 if (args[i] == '"')
149 in_quote = !in_quote;
150 }
151
152 *param = args;
153 if (!equals)
154 *val = NULL;
155 else {
156 args[equals] = '\0';
157 *val = args + equals + 1;
158
159 /* Don't include quotes in value. */
160 if (**val == '"') {
161 (*val)++;
162 if (args[i-1] == '"')
163 args[i-1] = '\0';
164 }
165 if (quoted && args[i-1] == '"')
166 args[i-1] = '\0';
167 }
168
169 if (args[i]) {
170 args[i] = '\0';
171 next = args + i + 1;
172 } else
173 next = args + i;
f36462f0
RR
174
175 /* Chew up trailing spaces. */
e7d2860b 176 return skip_spaces(next);
1da177e4
LT
177}
178
179/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
9fb48c74 180int parse_args(const char *doing,
1da177e4 181 char *args,
914dcaa8 182 const struct kernel_param *params,
1da177e4 183 unsigned num,
026cee00
PM
184 s16 min_level,
185 s16 max_level,
9fb48c74 186 int (*unknown)(char *param, char *val, const char *doing))
1da177e4
LT
187{
188 char *param, *val;
189
f36462f0 190 /* Chew leading spaces */
e7d2860b 191 args = skip_spaces(args);
f36462f0 192
1ef9eaf2 193 if (*args)
9fb48c74
JC
194 pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
195
1da177e4
LT
196 while (*args) {
197 int ret;
a416aba6 198 int irq_was_disabled;
1da177e4
LT
199
200 args = next_arg(args, &param, &val);
a416aba6 201 irq_was_disabled = irqs_disabled();
9fb48c74 202 ret = parse_one(param, val, doing, params, num,
026cee00 203 min_level, max_level, unknown);
b5f3abf9
JC
204 if (irq_was_disabled && !irqs_disabled())
205 pr_warn("%s: option '%s' enabled irq's!\n",
206 doing, param);
207
1da177e4
LT
208 switch (ret) {
209 case -ENOENT:
b5f3abf9 210 pr_err("%s: Unknown parameter `%s'\n", doing, param);
1da177e4
LT
211 return ret;
212 case -ENOSPC:
b5f3abf9 213 pr_err("%s: `%s' too large for parameter `%s'\n",
9fb48c74 214 doing, val ?: "", param);
1da177e4
LT
215 return ret;
216 case 0:
217 break;
218 default:
b5f3abf9 219 pr_err("%s: `%s' invalid for parameter `%s'\n",
9fb48c74 220 doing, val ?: "", param);
1da177e4
LT
221 return ret;
222 }
223 }
224
225 /* All parsed OK. */
226 return 0;
227}
228
229/* Lazy bastard, eh? */
230#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
9bbb9e5a 231 int param_set_##name(const char *val, const struct kernel_param *kp) \
1da177e4 232 { \
1da177e4 233 tmptype l; \
06b2a76d 234 int ret; \
1da177e4 235 \
06b2a76d 236 ret = strtolfn(val, 0, &l); \
81c74136
SM
237 if (ret < 0 || ((type)l != l)) \
238 return ret < 0 ? ret : -EINVAL; \
1da177e4
LT
239 *((type *)kp->arg) = l; \
240 return 0; \
241 } \
9bbb9e5a 242 int param_get_##name(char *buffer, const struct kernel_param *kp) \
1da177e4
LT
243 { \
244 return sprintf(buffer, format, *((type *)kp->arg)); \
a14fe249 245 } \
9bbb9e5a
RR
246 struct kernel_param_ops param_ops_##name = { \
247 .set = param_set_##name, \
248 .get = param_get_##name, \
249 }; \
a14fe249 250 EXPORT_SYMBOL(param_set_##name); \
9bbb9e5a
RR
251 EXPORT_SYMBOL(param_get_##name); \
252 EXPORT_SYMBOL(param_ops_##name)
253
1da177e4 254
06b2a76d
YY
255STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
256STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
257STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
258STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
259STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
260STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
261STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
1da177e4 262
9bbb9e5a 263int param_set_charp(const char *val, const struct kernel_param *kp)
1da177e4 264{
1da177e4 265 if (strlen(val) > 1024) {
b5f3abf9 266 pr_err("%s: string parameter too long\n", kp->name);
1da177e4
LT
267 return -ENOSPC;
268 }
269
a1054322
RR
270 maybe_kfree_parameter(*(char **)kp->arg);
271
272 /* This is a hack. We can't kmalloc in early boot, and we
e180a6b7
RR
273 * don't need to; this mangled commandline is preserved. */
274 if (slab_is_available()) {
a1054322 275 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
d553ad86 276 if (!*(char **)kp->arg)
e180a6b7 277 return -ENOMEM;
a1054322 278 strcpy(*(char **)kp->arg, val);
e180a6b7
RR
279 } else
280 *(const char **)kp->arg = val;
281
1da177e4
LT
282 return 0;
283}
a14fe249 284EXPORT_SYMBOL(param_set_charp);
1da177e4 285
9bbb9e5a 286int param_get_charp(char *buffer, const struct kernel_param *kp)
1da177e4
LT
287{
288 return sprintf(buffer, "%s", *((char **)kp->arg));
289}
a14fe249 290EXPORT_SYMBOL(param_get_charp);
1da177e4 291
a1054322
RR
292static void param_free_charp(void *arg)
293{
294 maybe_kfree_parameter(*((char **)arg));
295}
296
9bbb9e5a
RR
297struct kernel_param_ops param_ops_charp = {
298 .set = param_set_charp,
299 .get = param_get_charp,
a1054322 300 .free = param_free_charp,
9bbb9e5a
RR
301};
302EXPORT_SYMBOL(param_ops_charp);
303
fddd5201 304/* Actually could be a bool or an int, for historical reasons. */
9bbb9e5a 305int param_set_bool(const char *val, const struct kernel_param *kp)
1da177e4
LT
306{
307 /* No equals means "set"... */
308 if (!val) val = "1";
309
310 /* One of =[yYnN01] */
8b825281 311 return strtobool(val, kp->arg);
1da177e4 312}
a14fe249 313EXPORT_SYMBOL(param_set_bool);
1da177e4 314
9bbb9e5a 315int param_get_bool(char *buffer, const struct kernel_param *kp)
1da177e4
LT
316{
317 /* Y and N chosen as being relatively non-coder friendly */
8b825281 318 return sprintf(buffer, "%c", *(bool *)kp->arg ? 'Y' : 'N');
1da177e4 319}
a14fe249 320EXPORT_SYMBOL(param_get_bool);
1da177e4 321
9bbb9e5a
RR
322struct kernel_param_ops param_ops_bool = {
323 .set = param_set_bool,
324 .get = param_get_bool,
325};
326EXPORT_SYMBOL(param_ops_bool);
327
fddd5201 328/* This one must be bool. */
9bbb9e5a 329int param_set_invbool(const char *val, const struct kernel_param *kp)
1da177e4 330{
fddd5201
RR
331 int ret;
332 bool boolval;
22e48eaf 333 struct kernel_param dummy;
1da177e4 334
22e48eaf 335 dummy.arg = &boolval;
1da177e4
LT
336 ret = param_set_bool(val, &dummy);
337 if (ret == 0)
9a71af2c 338 *(bool *)kp->arg = !boolval;
1da177e4
LT
339 return ret;
340}
a14fe249 341EXPORT_SYMBOL(param_set_invbool);
1da177e4 342
9bbb9e5a 343int param_get_invbool(char *buffer, const struct kernel_param *kp)
1da177e4 344{
9a71af2c 345 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
1da177e4 346}
a14fe249 347EXPORT_SYMBOL(param_get_invbool);
1da177e4 348
9bbb9e5a
RR
349struct kernel_param_ops param_ops_invbool = {
350 .set = param_set_invbool,
351 .get = param_get_invbool,
352};
353EXPORT_SYMBOL(param_ops_invbool);
354
69116f27
RR
355int param_set_bint(const char *val, const struct kernel_param *kp)
356{
357 struct kernel_param boolkp;
358 bool v;
359 int ret;
360
361 /* Match bool exactly, by re-using it. */
362 boolkp = *kp;
363 boolkp.arg = &v;
69116f27
RR
364
365 ret = param_set_bool(val, &boolkp);
366 if (ret == 0)
367 *(int *)kp->arg = v;
368 return ret;
369}
370EXPORT_SYMBOL(param_set_bint);
371
372struct kernel_param_ops param_ops_bint = {
373 .set = param_set_bint,
374 .get = param_get_int,
375};
376EXPORT_SYMBOL(param_ops_bint);
377
9730b5b0 378/* We break the rule and mangle the string. */
9871728b
AB
379static int param_array(const char *name,
380 const char *val,
381 unsigned int min, unsigned int max,
382 void *elem, int elemsize,
9bbb9e5a 383 int (*set)(const char *, const struct kernel_param *kp),
026cee00 384 s16 level,
eb38a996 385 unsigned int *num)
1da177e4
LT
386{
387 int ret;
388 struct kernel_param kp;
389 char save;
390
391 /* Get the name right for errors. */
392 kp.name = name;
393 kp.arg = elem;
026cee00 394 kp.level = level;
1da177e4 395
1da177e4
LT
396 *num = 0;
397 /* We expect a comma-separated list of values. */
398 do {
399 int len;
400
401 if (*num == max) {
b5f3abf9 402 pr_err("%s: can only take %i arguments\n", name, max);
1da177e4
LT
403 return -EINVAL;
404 }
405 len = strcspn(val, ",");
406
407 /* nul-terminate and parse */
408 save = val[len];
409 ((char *)val)[len] = '\0';
907b29eb 410 BUG_ON(!mutex_is_locked(&param_lock));
1da177e4
LT
411 ret = set(val, &kp);
412
413 if (ret != 0)
414 return ret;
415 kp.arg += elemsize;
416 val += len+1;
417 (*num)++;
418 } while (save == ',');
419
420 if (*num < min) {
b5f3abf9 421 pr_err("%s: needs at least %i arguments\n", name, min);
1da177e4
LT
422 return -EINVAL;
423 }
424 return 0;
425}
426
9bbb9e5a 427static int param_array_set(const char *val, const struct kernel_param *kp)
1da177e4 428{
22e48eaf 429 const struct kparam_array *arr = kp->arr;
31143a12 430 unsigned int temp_num;
1da177e4
LT
431
432 return param_array(kp->name, val, 1, arr->max, arr->elem,
026cee00 433 arr->elemsize, arr->ops->set, kp->level,
3c7d76e3 434 arr->num ?: &temp_num);
1da177e4
LT
435}
436
9bbb9e5a 437static int param_array_get(char *buffer, const struct kernel_param *kp)
1da177e4
LT
438{
439 int i, off, ret;
22e48eaf 440 const struct kparam_array *arr = kp->arr;
1da177e4
LT
441 struct kernel_param p;
442
443 p = *kp;
444 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
445 if (i)
446 buffer[off++] = ',';
447 p.arg = arr->elem + arr->elemsize * i;
907b29eb 448 BUG_ON(!mutex_is_locked(&param_lock));
9bbb9e5a 449 ret = arr->ops->get(buffer + off, &p);
1da177e4
LT
450 if (ret < 0)
451 return ret;
452 off += ret;
453 }
454 buffer[off] = '\0';
455 return off;
456}
457
e6df34a4
RR
458static void param_array_free(void *arg)
459{
460 unsigned int i;
461 const struct kparam_array *arr = arg;
462
463 if (arr->ops->free)
464 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
465 arr->ops->free(arr->elem + arr->elemsize * i);
466}
467
9bbb9e5a
RR
468struct kernel_param_ops param_array_ops = {
469 .set = param_array_set,
470 .get = param_array_get,
e6df34a4 471 .free = param_array_free,
9bbb9e5a
RR
472};
473EXPORT_SYMBOL(param_array_ops);
474
475int param_set_copystring(const char *val, const struct kernel_param *kp)
1da177e4 476{
22e48eaf 477 const struct kparam_string *kps = kp->str;
1da177e4
LT
478
479 if (strlen(val)+1 > kps->maxlen) {
b5f3abf9 480 pr_err("%s: string doesn't fit in %u chars.\n",
1da177e4
LT
481 kp->name, kps->maxlen-1);
482 return -ENOSPC;
483 }
484 strcpy(kps->string, val);
485 return 0;
486}
a14fe249 487EXPORT_SYMBOL(param_set_copystring);
1da177e4 488
9bbb9e5a 489int param_get_string(char *buffer, const struct kernel_param *kp)
1da177e4 490{
22e48eaf 491 const struct kparam_string *kps = kp->str;
1da177e4
LT
492 return strlcpy(buffer, kps->string, kps->maxlen);
493}
a14fe249 494EXPORT_SYMBOL(param_get_string);
1da177e4 495
9bbb9e5a
RR
496struct kernel_param_ops param_ops_string = {
497 .set = param_set_copystring,
498 .get = param_get_string,
499};
500EXPORT_SYMBOL(param_ops_string);
501
1da177e4 502/* sysfs output in /sys/modules/XYZ/parameters/ */
350f8258
EY
503#define to_module_attr(n) container_of(n, struct module_attribute, attr)
504#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
1da177e4
LT
505
506extern struct kernel_param __start___param[], __stop___param[];
507
1da177e4
LT
508struct param_attribute
509{
510 struct module_attribute mattr;
9bbb9e5a 511 const struct kernel_param *param;
1da177e4
LT
512};
513
514struct module_param_attrs
515{
9b473de8 516 unsigned int num;
1da177e4
LT
517 struct attribute_group grp;
518 struct param_attribute attrs[0];
519};
520
ef665c1a 521#ifdef CONFIG_SYSFS
350f8258 522#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
1da177e4
LT
523
524static ssize_t param_attr_show(struct module_attribute *mattr,
4befb026 525 struct module_kobject *mk, char *buf)
1da177e4
LT
526{
527 int count;
528 struct param_attribute *attribute = to_param_attr(mattr);
529
9bbb9e5a 530 if (!attribute->param->ops->get)
1da177e4
LT
531 return -EPERM;
532
907b29eb 533 mutex_lock(&param_lock);
9bbb9e5a 534 count = attribute->param->ops->get(buf, attribute->param);
907b29eb 535 mutex_unlock(&param_lock);
1da177e4
LT
536 if (count > 0) {
537 strcat(buf, "\n");
538 ++count;
539 }
540 return count;
541}
542
543/* sysfs always hands a nul-terminated string in buf. We rely on that. */
544static ssize_t param_attr_store(struct module_attribute *mattr,
4befb026 545 struct module_kobject *km,
1da177e4
LT
546 const char *buf, size_t len)
547{
548 int err;
549 struct param_attribute *attribute = to_param_attr(mattr);
550
9bbb9e5a 551 if (!attribute->param->ops->set)
1da177e4
LT
552 return -EPERM;
553
907b29eb 554 mutex_lock(&param_lock);
9bbb9e5a 555 err = attribute->param->ops->set(buf, attribute->param);
907b29eb 556 mutex_unlock(&param_lock);
1da177e4
LT
557 if (!err)
558 return len;
559 return err;
560}
ef665c1a 561#endif
1da177e4
LT
562
563#ifdef CONFIG_MODULES
564#define __modinit
565#else
566#define __modinit __init
567#endif
568
ef665c1a 569#ifdef CONFIG_SYSFS
907b29eb
RR
570void __kernel_param_lock(void)
571{
572 mutex_lock(&param_lock);
573}
574EXPORT_SYMBOL(__kernel_param_lock);
575
576void __kernel_param_unlock(void)
577{
578 mutex_unlock(&param_lock);
579}
580EXPORT_SYMBOL(__kernel_param_unlock);
581
1da177e4 582/*
9b473de8
RR
583 * add_sysfs_param - add a parameter to sysfs
584 * @mk: struct module_kobject
585 * @kparam: the actual parameter definition to add to sysfs
586 * @name: name of parameter
1da177e4 587 *
9b473de8
RR
588 * Create a kobject if for a (per-module) parameter if mp NULL, and
589 * create file in sysfs. Returns an error on out of memory. Always cleans up
590 * if there's an error.
1da177e4 591 */
9b473de8 592static __modinit int add_sysfs_param(struct module_kobject *mk,
9bbb9e5a 593 const struct kernel_param *kp,
9b473de8 594 const char *name)
1da177e4 595{
9b473de8
RR
596 struct module_param_attrs *new;
597 struct attribute **attrs;
598 int err, num;
599
600 /* We don't bother calling this with invisible parameters. */
601 BUG_ON(!kp->perm);
602
603 if (!mk->mp) {
604 num = 0;
605 attrs = NULL;
606 } else {
607 num = mk->mp->num;
608 attrs = mk->mp->grp.attrs;
1da177e4
LT
609 }
610
9b473de8
RR
611 /* Enlarge. */
612 new = krealloc(mk->mp,
613 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
614 GFP_KERNEL);
615 if (!new) {
616 kfree(mk->mp);
617 err = -ENOMEM;
618 goto fail;
619 }
620 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
621 if (!attrs) {
622 err = -ENOMEM;
623 goto fail_free_new;
624 }
1da177e4 625
9b473de8
RR
626 /* Sysfs wants everything zeroed. */
627 memset(new, 0, sizeof(*new));
628 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
629 memset(&attrs[num], 0, sizeof(attrs[num]));
630 new->grp.name = "parameters";
631 new->grp.attrs = attrs;
632
633 /* Tack new one on the end. */
a07e4156 634 sysfs_attr_init(&new->attrs[num].mattr.attr);
9b473de8
RR
635 new->attrs[num].param = kp;
636 new->attrs[num].mattr.show = param_attr_show;
637 new->attrs[num].mattr.store = param_attr_store;
638 new->attrs[num].mattr.attr.name = (char *)name;
639 new->attrs[num].mattr.attr.mode = kp->perm;
640 new->num = num+1;
641
642 /* Fix up all the pointers, since krealloc can move us */
643 for (num = 0; num < new->num; num++)
644 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
645 new->grp.attrs[num] = NULL;
646
647 mk->mp = new;
648 return 0;
1da177e4 649
9b473de8
RR
650fail_free_new:
651 kfree(new);
652fail:
653 mk->mp = NULL;
654 return err;
655}
1da177e4 656
d2441183 657#ifdef CONFIG_MODULES
9b473de8
RR
658static void free_module_param_attrs(struct module_kobject *mk)
659{
660 kfree(mk->mp->grp.attrs);
661 kfree(mk->mp);
662 mk->mp = NULL;
1da177e4
LT
663}
664
1da177e4
LT
665/*
666 * module_param_sysfs_setup - setup sysfs support for one module
667 * @mod: module
668 * @kparam: module parameters (array)
669 * @num_params: number of module parameters
670 *
9b473de8
RR
671 * Adds sysfs entries for module parameters under
672 * /sys/module/[mod->name]/parameters/
1da177e4
LT
673 */
674int module_param_sysfs_setup(struct module *mod,
9bbb9e5a 675 const struct kernel_param *kparam,
1da177e4
LT
676 unsigned int num_params)
677{
9b473de8
RR
678 int i, err;
679 bool params = false;
680
681 for (i = 0; i < num_params; i++) {
682 if (kparam[i].perm == 0)
683 continue;
684 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
685 if (err)
686 return err;
687 params = true;
688 }
1da177e4 689
9b473de8
RR
690 if (!params)
691 return 0;
1da177e4 692
9b473de8
RR
693 /* Create the param group. */
694 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
695 if (err)
696 free_module_param_attrs(&mod->mkobj);
697 return err;
1da177e4
LT
698}
699
700/*
701 * module_param_sysfs_remove - remove sysfs support for one module
702 * @mod: module
703 *
704 * Remove sysfs entries for module parameters and the corresponding
705 * kobject.
706 */
707void module_param_sysfs_remove(struct module *mod)
708{
9b473de8
RR
709 if (mod->mkobj.mp) {
710 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
1da177e4
LT
711 /* We are positive that no one is using any param
712 * attrs at this point. Deallocate immediately. */
9b473de8 713 free_module_param_attrs(&mod->mkobj);
1da177e4
LT
714 }
715}
716#endif
717
e180a6b7
RR
718void destroy_params(const struct kernel_param *params, unsigned num)
719{
e6df34a4
RR
720 unsigned int i;
721
722 for (i = 0; i < num; i++)
723 if (params[i].ops->free)
724 params[i].ops->free(params[i].arg);
e180a6b7
RR
725}
726
e94965ed 727static struct module_kobject * __init locate_module_kobject(const char *name)
1da177e4
LT
728{
729 struct module_kobject *mk;
9b473de8
RR
730 struct kobject *kobj;
731 int err;
1da177e4 732
9b473de8
RR
733 kobj = kset_find_obj(module_kset, name);
734 if (kobj) {
9b473de8 735 mk = to_module_kobject(kobj);
9b473de8
RR
736 } else {
737 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
738 BUG_ON(!mk);
739
740 mk->mod = THIS_MODULE;
741 mk->kobj.kset = module_kset;
742 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
743 "%s", name);
88bfa324
KS
744#ifdef CONFIG_MODULES
745 if (!err)
746 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
747#endif
9b473de8
RR
748 if (err) {
749 kobject_put(&mk->kobj);
b5f3abf9 750 pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n",
e94965ed 751 name, err);
e94965ed 752 return NULL;
9b473de8 753 }
e94965ed
DT
754
755 /* So that we hold reference in both cases. */
9b473de8 756 kobject_get(&mk->kobj);
74c5b597 757 }
9b473de8 758
e94965ed
DT
759 return mk;
760}
761
762static void __init kernel_add_sysfs_param(const char *name,
763 struct kernel_param *kparam,
764 unsigned int name_skip)
765{
766 struct module_kobject *mk;
767 int err;
768
769 mk = locate_module_kobject(name);
770 if (!mk)
771 return;
772
773 /* We need to remove old parameters before adding more. */
774 if (mk->mp)
775 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
776
9b473de8
RR
777 /* These should not fail at boot. */
778 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
779 BUG_ON(err);
780 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
781 BUG_ON(err);
f30c53a8 782 kobject_uevent(&mk->kobj, KOBJ_ADD);
9b473de8 783 kobject_put(&mk->kobj);
1da177e4
LT
784}
785
786/*
787 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
788 *
789 * Add module_parameters to sysfs for "modules" built into the kernel.
790 *
791 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
792 * "parameter" name is stored behind a dot in kernel_param->name. So,
793 * extract the "module" name for all built-in kernel_param-eters,
9b473de8 794 * and for all who have the same, call kernel_add_sysfs_param.
1da177e4
LT
795 */
796static void __init param_sysfs_builtin(void)
797{
9b473de8
RR
798 struct kernel_param *kp;
799 unsigned int name_len;
800 char modname[MODULE_NAME_LEN];
1da177e4 801
9b473de8 802 for (kp = __start___param; kp < __stop___param; kp++) {
1da177e4
LT
803 char *dot;
804
9b473de8
RR
805 if (kp->perm == 0)
806 continue;
1da177e4 807
730b69d2 808 dot = strchr(kp->name, '.');
1da177e4 809 if (!dot) {
67e67cea
RR
810 /* This happens for core_param() */
811 strcpy(modname, "kernel");
812 name_len = 0;
813 } else {
814 name_len = dot - kp->name + 1;
815 strlcpy(modname, kp->name, name_len);
1da177e4 816 }
67e67cea 817 kernel_add_sysfs_param(modname, kp, name_len);
1da177e4 818 }
1da177e4
LT
819}
820
e94965ed 821ssize_t __modver_version_show(struct module_attribute *mattr,
4befb026 822 struct module_kobject *mk, char *buf)
e94965ed
DT
823{
824 struct module_version_attribute *vattr =
825 container_of(mattr, struct module_version_attribute, mattr);
826
827 return sprintf(buf, "%s\n", vattr->version);
828}
829
b4bc8428
DT
830extern const struct module_version_attribute *__start___modver[];
831extern const struct module_version_attribute *__stop___modver[];
e94965ed
DT
832
833static void __init version_sysfs_builtin(void)
834{
b4bc8428 835 const struct module_version_attribute **p;
e94965ed
DT
836 struct module_kobject *mk;
837 int err;
838
b4bc8428
DT
839 for (p = __start___modver; p < __stop___modver; p++) {
840 const struct module_version_attribute *vattr = *p;
841
e94965ed
DT
842 mk = locate_module_kobject(vattr->module_name);
843 if (mk) {
844 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
845 kobject_uevent(&mk->kobj, KOBJ_ADD);
846 kobject_put(&mk->kobj);
847 }
848 }
849}
1da177e4
LT
850
851/* module-related sysfs stuff */
1da177e4 852
1da177e4
LT
853static ssize_t module_attr_show(struct kobject *kobj,
854 struct attribute *attr,
855 char *buf)
856{
857 struct module_attribute *attribute;
858 struct module_kobject *mk;
859 int ret;
860
861 attribute = to_module_attr(attr);
862 mk = to_module_kobject(kobj);
863
864 if (!attribute->show)
70f2817a 865 return -EIO;
1da177e4 866
4befb026 867 ret = attribute->show(attribute, mk, buf);
1da177e4 868
1da177e4
LT
869 return ret;
870}
871
872static ssize_t module_attr_store(struct kobject *kobj,
873 struct attribute *attr,
874 const char *buf, size_t len)
875{
876 struct module_attribute *attribute;
877 struct module_kobject *mk;
878 int ret;
879
880 attribute = to_module_attr(attr);
881 mk = to_module_kobject(kobj);
882
883 if (!attribute->store)
70f2817a 884 return -EIO;
1da177e4 885
4befb026 886 ret = attribute->store(attribute, mk, buf, len);
1da177e4 887
1da177e4
LT
888 return ret;
889}
890
52cf25d0 891static const struct sysfs_ops module_sysfs_ops = {
1da177e4
LT
892 .show = module_attr_show,
893 .store = module_attr_store,
894};
895
270a6c4c
KS
896static int uevent_filter(struct kset *kset, struct kobject *kobj)
897{
898 struct kobj_type *ktype = get_ktype(kobj);
899
900 if (ktype == &module_ktype)
901 return 1;
902 return 0;
903}
904
9cd43611 905static const struct kset_uevent_ops module_uevent_ops = {
270a6c4c
KS
906 .filter = uevent_filter,
907};
908
7405c1e1 909struct kset *module_kset;
823bccfc 910int module_sysfs_initialized;
1da177e4 911
7405c1e1 912struct kobj_type module_ktype = {
1da177e4
LT
913 .sysfs_ops = &module_sysfs_ops,
914};
915
1da177e4
LT
916/*
917 * param_sysfs_init - wrapper for built-in params support
918 */
919static int __init param_sysfs_init(void)
920{
7405c1e1
GKH
921 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
922 if (!module_kset) {
923 printk(KERN_WARNING "%s (%d): error creating kset\n",
924 __FILE__, __LINE__);
925 return -ENOMEM;
d8c7649e 926 }
823bccfc 927 module_sysfs_initialized = 1;
1da177e4 928
e94965ed 929 version_sysfs_builtin();
1da177e4
LT
930 param_sysfs_builtin();
931
932 return 0;
933}
d10be6d1 934subsys_initcall(param_sysfs_init);
1da177e4 935
7405c1e1 936#endif /* CONFIG_SYSFS */