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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. */
ab013c5f
SR
106 if (!val &&
107 !(params[i].ops->flags & KERNEL_PARAM_FL_NOARG))
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? */
88a88b32 230#define STANDARD_PARAM_DEF(name, type, format, strtolfn) \
9bbb9e5a 231 int param_set_##name(const char *val, const struct kernel_param *kp) \
1da177e4 232 { \
88a88b32 233 return strtolfn(val, 0, (type *)kp->arg); \
1da177e4 234 } \
9bbb9e5a 235 int param_get_##name(char *buffer, const struct kernel_param *kp) \
1da177e4 236 { \
f4940ab7
CG
237 return scnprintf(buffer, PAGE_SIZE, format, \
238 *((type *)kp->arg)); \
a14fe249 239 } \
9bbb9e5a
RR
240 struct kernel_param_ops param_ops_##name = { \
241 .set = param_set_##name, \
242 .get = param_get_##name, \
243 }; \
a14fe249 244 EXPORT_SYMBOL(param_set_##name); \
9bbb9e5a
RR
245 EXPORT_SYMBOL(param_get_##name); \
246 EXPORT_SYMBOL(param_ops_##name)
247
1da177e4 248
88a88b32
FC
249STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8);
250STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16);
251STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16);
252STANDARD_PARAM_DEF(int, int, "%i", kstrtoint);
253STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint);
254STANDARD_PARAM_DEF(long, long, "%li", kstrtol);
255STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul);
1da177e4 256
9bbb9e5a 257int param_set_charp(const char *val, const struct kernel_param *kp)
1da177e4 258{
1da177e4 259 if (strlen(val) > 1024) {
b5f3abf9 260 pr_err("%s: string parameter too long\n", kp->name);
1da177e4
LT
261 return -ENOSPC;
262 }
263
a1054322
RR
264 maybe_kfree_parameter(*(char **)kp->arg);
265
266 /* This is a hack. We can't kmalloc in early boot, and we
e180a6b7
RR
267 * don't need to; this mangled commandline is preserved. */
268 if (slab_is_available()) {
a1054322 269 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
d553ad86 270 if (!*(char **)kp->arg)
e180a6b7 271 return -ENOMEM;
a1054322 272 strcpy(*(char **)kp->arg, val);
e180a6b7
RR
273 } else
274 *(const char **)kp->arg = val;
275
1da177e4
LT
276 return 0;
277}
a14fe249 278EXPORT_SYMBOL(param_set_charp);
1da177e4 279
9bbb9e5a 280int param_get_charp(char *buffer, const struct kernel_param *kp)
1da177e4 281{
f4940ab7 282 return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg));
1da177e4 283}
a14fe249 284EXPORT_SYMBOL(param_get_charp);
1da177e4 285
a1054322
RR
286static void param_free_charp(void *arg)
287{
288 maybe_kfree_parameter(*((char **)arg));
289}
290
9bbb9e5a
RR
291struct kernel_param_ops param_ops_charp = {
292 .set = param_set_charp,
293 .get = param_get_charp,
a1054322 294 .free = param_free_charp,
9bbb9e5a
RR
295};
296EXPORT_SYMBOL(param_ops_charp);
297
fddd5201 298/* Actually could be a bool or an int, for historical reasons. */
9bbb9e5a 299int param_set_bool(const char *val, const struct kernel_param *kp)
1da177e4
LT
300{
301 /* No equals means "set"... */
302 if (!val) val = "1";
303
304 /* One of =[yYnN01] */
8b825281 305 return strtobool(val, kp->arg);
1da177e4 306}
a14fe249 307EXPORT_SYMBOL(param_set_bool);
1da177e4 308
9bbb9e5a 309int param_get_bool(char *buffer, const struct kernel_param *kp)
1da177e4
LT
310{
311 /* Y and N chosen as being relatively non-coder friendly */
8b825281 312 return sprintf(buffer, "%c", *(bool *)kp->arg ? 'Y' : 'N');
1da177e4 313}
a14fe249 314EXPORT_SYMBOL(param_get_bool);
1da177e4 315
9bbb9e5a 316struct kernel_param_ops param_ops_bool = {
ab013c5f 317 .flags = KERNEL_PARAM_FL_NOARG,
9bbb9e5a
RR
318 .set = param_set_bool,
319 .get = param_get_bool,
320};
321EXPORT_SYMBOL(param_ops_bool);
322
fddd5201 323/* This one must be bool. */
9bbb9e5a 324int param_set_invbool(const char *val, const struct kernel_param *kp)
1da177e4 325{
fddd5201
RR
326 int ret;
327 bool boolval;
22e48eaf 328 struct kernel_param dummy;
1da177e4 329
22e48eaf 330 dummy.arg = &boolval;
1da177e4
LT
331 ret = param_set_bool(val, &dummy);
332 if (ret == 0)
9a71af2c 333 *(bool *)kp->arg = !boolval;
1da177e4
LT
334 return ret;
335}
a14fe249 336EXPORT_SYMBOL(param_set_invbool);
1da177e4 337
9bbb9e5a 338int param_get_invbool(char *buffer, const struct kernel_param *kp)
1da177e4 339{
9a71af2c 340 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
1da177e4 341}
a14fe249 342EXPORT_SYMBOL(param_get_invbool);
1da177e4 343
9bbb9e5a
RR
344struct kernel_param_ops param_ops_invbool = {
345 .set = param_set_invbool,
346 .get = param_get_invbool,
347};
348EXPORT_SYMBOL(param_ops_invbool);
349
69116f27
RR
350int param_set_bint(const char *val, const struct kernel_param *kp)
351{
352 struct kernel_param boolkp;
353 bool v;
354 int ret;
355
356 /* Match bool exactly, by re-using it. */
357 boolkp = *kp;
358 boolkp.arg = &v;
69116f27
RR
359
360 ret = param_set_bool(val, &boolkp);
361 if (ret == 0)
362 *(int *)kp->arg = v;
363 return ret;
364}
365EXPORT_SYMBOL(param_set_bint);
366
367struct kernel_param_ops param_ops_bint = {
ab013c5f 368 .flags = KERNEL_PARAM_FL_NOARG,
69116f27
RR
369 .set = param_set_bint,
370 .get = param_get_int,
371};
372EXPORT_SYMBOL(param_ops_bint);
373
9730b5b0 374/* We break the rule and mangle the string. */
9871728b
AB
375static int param_array(const char *name,
376 const char *val,
377 unsigned int min, unsigned int max,
378 void *elem, int elemsize,
9bbb9e5a 379 int (*set)(const char *, const struct kernel_param *kp),
026cee00 380 s16 level,
eb38a996 381 unsigned int *num)
1da177e4
LT
382{
383 int ret;
384 struct kernel_param kp;
385 char save;
386
387 /* Get the name right for errors. */
388 kp.name = name;
389 kp.arg = elem;
026cee00 390 kp.level = level;
1da177e4 391
1da177e4
LT
392 *num = 0;
393 /* We expect a comma-separated list of values. */
394 do {
395 int len;
396
397 if (*num == max) {
b5f3abf9 398 pr_err("%s: can only take %i arguments\n", name, max);
1da177e4
LT
399 return -EINVAL;
400 }
401 len = strcspn(val, ",");
402
403 /* nul-terminate and parse */
404 save = val[len];
405 ((char *)val)[len] = '\0';
907b29eb 406 BUG_ON(!mutex_is_locked(&param_lock));
1da177e4
LT
407 ret = set(val, &kp);
408
409 if (ret != 0)
410 return ret;
411 kp.arg += elemsize;
412 val += len+1;
413 (*num)++;
414 } while (save == ',');
415
416 if (*num < min) {
b5f3abf9 417 pr_err("%s: needs at least %i arguments\n", name, min);
1da177e4
LT
418 return -EINVAL;
419 }
420 return 0;
421}
422
9bbb9e5a 423static int param_array_set(const char *val, const struct kernel_param *kp)
1da177e4 424{
22e48eaf 425 const struct kparam_array *arr = kp->arr;
31143a12 426 unsigned int temp_num;
1da177e4
LT
427
428 return param_array(kp->name, val, 1, arr->max, arr->elem,
026cee00 429 arr->elemsize, arr->ops->set, kp->level,
3c7d76e3 430 arr->num ?: &temp_num);
1da177e4
LT
431}
432
9bbb9e5a 433static int param_array_get(char *buffer, const struct kernel_param *kp)
1da177e4
LT
434{
435 int i, off, ret;
22e48eaf 436 const struct kparam_array *arr = kp->arr;
1da177e4
LT
437 struct kernel_param p;
438
439 p = *kp;
440 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
441 if (i)
442 buffer[off++] = ',';
443 p.arg = arr->elem + arr->elemsize * i;
907b29eb 444 BUG_ON(!mutex_is_locked(&param_lock));
9bbb9e5a 445 ret = arr->ops->get(buffer + off, &p);
1da177e4
LT
446 if (ret < 0)
447 return ret;
448 off += ret;
449 }
450 buffer[off] = '\0';
451 return off;
452}
453
e6df34a4
RR
454static void param_array_free(void *arg)
455{
456 unsigned int i;
457 const struct kparam_array *arr = arg;
458
459 if (arr->ops->free)
460 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
461 arr->ops->free(arr->elem + arr->elemsize * i);
462}
463
9bbb9e5a
RR
464struct kernel_param_ops param_array_ops = {
465 .set = param_array_set,
466 .get = param_array_get,
e6df34a4 467 .free = param_array_free,
9bbb9e5a
RR
468};
469EXPORT_SYMBOL(param_array_ops);
470
471int param_set_copystring(const char *val, const struct kernel_param *kp)
1da177e4 472{
22e48eaf 473 const struct kparam_string *kps = kp->str;
1da177e4
LT
474
475 if (strlen(val)+1 > kps->maxlen) {
b5f3abf9 476 pr_err("%s: string doesn't fit in %u chars.\n",
1da177e4
LT
477 kp->name, kps->maxlen-1);
478 return -ENOSPC;
479 }
480 strcpy(kps->string, val);
481 return 0;
482}
a14fe249 483EXPORT_SYMBOL(param_set_copystring);
1da177e4 484
9bbb9e5a 485int param_get_string(char *buffer, const struct kernel_param *kp)
1da177e4 486{
22e48eaf 487 const struct kparam_string *kps = kp->str;
1da177e4
LT
488 return strlcpy(buffer, kps->string, kps->maxlen);
489}
a14fe249 490EXPORT_SYMBOL(param_get_string);
1da177e4 491
9bbb9e5a
RR
492struct kernel_param_ops param_ops_string = {
493 .set = param_set_copystring,
494 .get = param_get_string,
495};
496EXPORT_SYMBOL(param_ops_string);
497
1da177e4 498/* sysfs output in /sys/modules/XYZ/parameters/ */
350f8258
EY
499#define to_module_attr(n) container_of(n, struct module_attribute, attr)
500#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
1da177e4
LT
501
502extern struct kernel_param __start___param[], __stop___param[];
503
1da177e4
LT
504struct param_attribute
505{
506 struct module_attribute mattr;
9bbb9e5a 507 const struct kernel_param *param;
1da177e4
LT
508};
509
510struct module_param_attrs
511{
9b473de8 512 unsigned int num;
1da177e4
LT
513 struct attribute_group grp;
514 struct param_attribute attrs[0];
515};
516
ef665c1a 517#ifdef CONFIG_SYSFS
350f8258 518#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
1da177e4
LT
519
520static ssize_t param_attr_show(struct module_attribute *mattr,
4befb026 521 struct module_kobject *mk, char *buf)
1da177e4
LT
522{
523 int count;
524 struct param_attribute *attribute = to_param_attr(mattr);
525
9bbb9e5a 526 if (!attribute->param->ops->get)
1da177e4
LT
527 return -EPERM;
528
907b29eb 529 mutex_lock(&param_lock);
9bbb9e5a 530 count = attribute->param->ops->get(buf, attribute->param);
907b29eb 531 mutex_unlock(&param_lock);
1da177e4
LT
532 if (count > 0) {
533 strcat(buf, "\n");
534 ++count;
535 }
536 return count;
537}
538
539/* sysfs always hands a nul-terminated string in buf. We rely on that. */
540static ssize_t param_attr_store(struct module_attribute *mattr,
4befb026 541 struct module_kobject *km,
1da177e4
LT
542 const char *buf, size_t len)
543{
544 int err;
545 struct param_attribute *attribute = to_param_attr(mattr);
546
9bbb9e5a 547 if (!attribute->param->ops->set)
1da177e4
LT
548 return -EPERM;
549
907b29eb 550 mutex_lock(&param_lock);
9bbb9e5a 551 err = attribute->param->ops->set(buf, attribute->param);
907b29eb 552 mutex_unlock(&param_lock);
1da177e4
LT
553 if (!err)
554 return len;
555 return err;
556}
ef665c1a 557#endif
1da177e4
LT
558
559#ifdef CONFIG_MODULES
560#define __modinit
561#else
562#define __modinit __init
563#endif
564
ef665c1a 565#ifdef CONFIG_SYSFS
907b29eb
RR
566void __kernel_param_lock(void)
567{
568 mutex_lock(&param_lock);
569}
570EXPORT_SYMBOL(__kernel_param_lock);
571
572void __kernel_param_unlock(void)
573{
574 mutex_unlock(&param_lock);
575}
576EXPORT_SYMBOL(__kernel_param_unlock);
577
1da177e4 578/*
9b473de8
RR
579 * add_sysfs_param - add a parameter to sysfs
580 * @mk: struct module_kobject
581 * @kparam: the actual parameter definition to add to sysfs
582 * @name: name of parameter
1da177e4 583 *
9b473de8
RR
584 * Create a kobject if for a (per-module) parameter if mp NULL, and
585 * create file in sysfs. Returns an error on out of memory. Always cleans up
586 * if there's an error.
1da177e4 587 */
9b473de8 588static __modinit int add_sysfs_param(struct module_kobject *mk,
9bbb9e5a 589 const struct kernel_param *kp,
9b473de8 590 const char *name)
1da177e4 591{
9b473de8
RR
592 struct module_param_attrs *new;
593 struct attribute **attrs;
594 int err, num;
595
596 /* We don't bother calling this with invisible parameters. */
597 BUG_ON(!kp->perm);
598
599 if (!mk->mp) {
600 num = 0;
601 attrs = NULL;
602 } else {
603 num = mk->mp->num;
604 attrs = mk->mp->grp.attrs;
1da177e4
LT
605 }
606
9b473de8
RR
607 /* Enlarge. */
608 new = krealloc(mk->mp,
609 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
610 GFP_KERNEL);
611 if (!new) {
63662139 612 kfree(attrs);
9b473de8
RR
613 err = -ENOMEM;
614 goto fail;
615 }
63662139
DW
616 /* Despite looking like the typical realloc() bug, this is safe.
617 * We *want* the old 'attrs' to be freed either way, and we'll store
618 * the new one in the success case. */
9b473de8
RR
619 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
620 if (!attrs) {
621 err = -ENOMEM;
622 goto fail_free_new;
623 }
1da177e4 624
9b473de8
RR
625 /* Sysfs wants everything zeroed. */
626 memset(new, 0, sizeof(*new));
627 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
628 memset(&attrs[num], 0, sizeof(attrs[num]));
629 new->grp.name = "parameters";
630 new->grp.attrs = attrs;
631
632 /* Tack new one on the end. */
a07e4156 633 sysfs_attr_init(&new->attrs[num].mattr.attr);
9b473de8
RR
634 new->attrs[num].param = kp;
635 new->attrs[num].mattr.show = param_attr_show;
636 new->attrs[num].mattr.store = param_attr_store;
637 new->attrs[num].mattr.attr.name = (char *)name;
638 new->attrs[num].mattr.attr.mode = kp->perm;
639 new->num = num+1;
640
641 /* Fix up all the pointers, since krealloc can move us */
642 for (num = 0; num < new->num; num++)
643 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
644 new->grp.attrs[num] = NULL;
645
646 mk->mp = new;
647 return 0;
1da177e4 648
9b473de8
RR
649fail_free_new:
650 kfree(new);
651fail:
652 mk->mp = NULL;
653 return err;
654}
1da177e4 655
d2441183 656#ifdef CONFIG_MODULES
9b473de8
RR
657static void free_module_param_attrs(struct module_kobject *mk)
658{
659 kfree(mk->mp->grp.attrs);
660 kfree(mk->mp);
661 mk->mp = NULL;
1da177e4
LT
662}
663
1da177e4
LT
664/*
665 * module_param_sysfs_setup - setup sysfs support for one module
666 * @mod: module
667 * @kparam: module parameters (array)
668 * @num_params: number of module parameters
669 *
9b473de8
RR
670 * Adds sysfs entries for module parameters under
671 * /sys/module/[mod->name]/parameters/
1da177e4
LT
672 */
673int module_param_sysfs_setup(struct module *mod,
9bbb9e5a 674 const struct kernel_param *kparam,
1da177e4
LT
675 unsigned int num_params)
676{
9b473de8
RR
677 int i, err;
678 bool params = false;
679
680 for (i = 0; i < num_params; i++) {
681 if (kparam[i].perm == 0)
682 continue;
683 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
684 if (err)
685 return err;
686 params = true;
687 }
1da177e4 688
9b473de8
RR
689 if (!params)
690 return 0;
1da177e4 691
9b473de8
RR
692 /* Create the param group. */
693 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
694 if (err)
695 free_module_param_attrs(&mod->mkobj);
696 return err;
1da177e4
LT
697}
698
699/*
700 * module_param_sysfs_remove - remove sysfs support for one module
701 * @mod: module
702 *
703 * Remove sysfs entries for module parameters and the corresponding
704 * kobject.
705 */
706void module_param_sysfs_remove(struct module *mod)
707{
9b473de8
RR
708 if (mod->mkobj.mp) {
709 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
1da177e4
LT
710 /* We are positive that no one is using any param
711 * attrs at this point. Deallocate immediately. */
9b473de8 712 free_module_param_attrs(&mod->mkobj);
1da177e4
LT
713 }
714}
715#endif
716
e180a6b7
RR
717void destroy_params(const struct kernel_param *params, unsigned num)
718{
e6df34a4
RR
719 unsigned int i;
720
721 for (i = 0; i < num; i++)
722 if (params[i].ops->free)
723 params[i].ops->free(params[i].arg);
e180a6b7
RR
724}
725
e94965ed 726static struct module_kobject * __init locate_module_kobject(const char *name)
1da177e4
LT
727{
728 struct module_kobject *mk;
9b473de8
RR
729 struct kobject *kobj;
730 int err;
1da177e4 731
9b473de8
RR
732 kobj = kset_find_obj(module_kset, name);
733 if (kobj) {
9b473de8 734 mk = to_module_kobject(kobj);
9b473de8
RR
735 } else {
736 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
737 BUG_ON(!mk);
738
739 mk->mod = THIS_MODULE;
740 mk->kobj.kset = module_kset;
741 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
742 "%s", name);
88bfa324
KS
743#ifdef CONFIG_MODULES
744 if (!err)
745 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
746#endif
9b473de8
RR
747 if (err) {
748 kobject_put(&mk->kobj);
b5f3abf9 749 pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n",
e94965ed 750 name, err);
e94965ed 751 return NULL;
9b473de8 752 }
e94965ed
DT
753
754 /* So that we hold reference in both cases. */
9b473de8 755 kobject_get(&mk->kobj);
74c5b597 756 }
9b473de8 757
e94965ed
DT
758 return mk;
759}
760
761static void __init kernel_add_sysfs_param(const char *name,
762 struct kernel_param *kparam,
763 unsigned int name_skip)
764{
765 struct module_kobject *mk;
766 int err;
767
768 mk = locate_module_kobject(name);
769 if (!mk)
770 return;
771
772 /* We need to remove old parameters before adding more. */
773 if (mk->mp)
774 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
775
9b473de8
RR
776 /* These should not fail at boot. */
777 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
778 BUG_ON(err);
779 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
780 BUG_ON(err);
f30c53a8 781 kobject_uevent(&mk->kobj, KOBJ_ADD);
9b473de8 782 kobject_put(&mk->kobj);
1da177e4
LT
783}
784
785/*
b634d130 786 * param_sysfs_builtin - add sysfs parameters for built-in modules
1da177e4
LT
787 *
788 * Add module_parameters to sysfs for "modules" built into the kernel.
789 *
790 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
791 * "parameter" name is stored behind a dot in kernel_param->name. So,
792 * extract the "module" name for all built-in kernel_param-eters,
9b473de8 793 * and for all who have the same, call kernel_add_sysfs_param.
1da177e4
LT
794 */
795static void __init param_sysfs_builtin(void)
796{
9b473de8
RR
797 struct kernel_param *kp;
798 unsigned int name_len;
799 char modname[MODULE_NAME_LEN];
1da177e4 800
9b473de8 801 for (kp = __start___param; kp < __stop___param; kp++) {
1da177e4
LT
802 char *dot;
803
9b473de8
RR
804 if (kp->perm == 0)
805 continue;
1da177e4 806
730b69d2 807 dot = strchr(kp->name, '.');
1da177e4 808 if (!dot) {
67e67cea
RR
809 /* This happens for core_param() */
810 strcpy(modname, "kernel");
811 name_len = 0;
812 } else {
813 name_len = dot - kp->name + 1;
814 strlcpy(modname, kp->name, name_len);
1da177e4 815 }
67e67cea 816 kernel_add_sysfs_param(modname, kp, name_len);
1da177e4 817 }
1da177e4
LT
818}
819
e94965ed 820ssize_t __modver_version_show(struct module_attribute *mattr,
4befb026 821 struct module_kobject *mk, char *buf)
e94965ed
DT
822{
823 struct module_version_attribute *vattr =
824 container_of(mattr, struct module_version_attribute, mattr);
825
f4940ab7 826 return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
e94965ed
DT
827}
828
b4bc8428
DT
829extern const struct module_version_attribute *__start___modver[];
830extern const struct module_version_attribute *__stop___modver[];
e94965ed
DT
831
832static void __init version_sysfs_builtin(void)
833{
b4bc8428 834 const struct module_version_attribute **p;
e94965ed
DT
835 struct module_kobject *mk;
836 int err;
837
b4bc8428
DT
838 for (p = __start___modver; p < __stop___modver; p++) {
839 const struct module_version_attribute *vattr = *p;
840
e94965ed
DT
841 mk = locate_module_kobject(vattr->module_name);
842 if (mk) {
843 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
844 kobject_uevent(&mk->kobj, KOBJ_ADD);
845 kobject_put(&mk->kobj);
846 }
847 }
848}
1da177e4
LT
849
850/* module-related sysfs stuff */
1da177e4 851
1da177e4
LT
852static ssize_t module_attr_show(struct kobject *kobj,
853 struct attribute *attr,
854 char *buf)
855{
856 struct module_attribute *attribute;
857 struct module_kobject *mk;
858 int ret;
859
860 attribute = to_module_attr(attr);
861 mk = to_module_kobject(kobj);
862
863 if (!attribute->show)
70f2817a 864 return -EIO;
1da177e4 865
4befb026 866 ret = attribute->show(attribute, mk, buf);
1da177e4 867
1da177e4
LT
868 return ret;
869}
870
871static ssize_t module_attr_store(struct kobject *kobj,
872 struct attribute *attr,
873 const char *buf, size_t len)
874{
875 struct module_attribute *attribute;
876 struct module_kobject *mk;
877 int ret;
878
879 attribute = to_module_attr(attr);
880 mk = to_module_kobject(kobj);
881
882 if (!attribute->store)
70f2817a 883 return -EIO;
1da177e4 884
4befb026 885 ret = attribute->store(attribute, mk, buf, len);
1da177e4 886
1da177e4
LT
887 return ret;
888}
889
52cf25d0 890static const struct sysfs_ops module_sysfs_ops = {
1da177e4
LT
891 .show = module_attr_show,
892 .store = module_attr_store,
893};
894
270a6c4c
KS
895static int uevent_filter(struct kset *kset, struct kobject *kobj)
896{
897 struct kobj_type *ktype = get_ktype(kobj);
898
899 if (ktype == &module_ktype)
900 return 1;
901 return 0;
902}
903
9cd43611 904static const struct kset_uevent_ops module_uevent_ops = {
270a6c4c
KS
905 .filter = uevent_filter,
906};
907
7405c1e1 908struct kset *module_kset;
823bccfc 909int module_sysfs_initialized;
1da177e4 910
942e4431
LZ
911static void module_kobj_release(struct kobject *kobj)
912{
913 struct module_kobject *mk = to_module_kobject(kobj);
914 complete(mk->kobj_completion);
915}
916
7405c1e1 917struct kobj_type module_ktype = {
942e4431 918 .release = module_kobj_release,
1da177e4
LT
919 .sysfs_ops = &module_sysfs_ops,
920};
921
1da177e4
LT
922/*
923 * param_sysfs_init - wrapper for built-in params support
924 */
925static int __init param_sysfs_init(void)
926{
7405c1e1
GKH
927 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
928 if (!module_kset) {
929 printk(KERN_WARNING "%s (%d): error creating kset\n",
930 __FILE__, __LINE__);
931 return -ENOMEM;
d8c7649e 932 }
823bccfc 933 module_sysfs_initialized = 1;
1da177e4 934
e94965ed 935 version_sysfs_builtin();
1da177e4
LT
936 param_sysfs_builtin();
937
938 return 0;
939}
d10be6d1 940subsys_initcall(param_sysfs_init);
1da177e4 941
7405c1e1 942#endif /* CONFIG_SYSFS */