blob: 2a4ba258f04fc4cd6b3d67981c3fe7982e3f8099 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* 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*/
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/moduleparam.h>
19#include <linux/kernel.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/module.h>
23#include <linux/device.h>
24#include <linux/err.h>
Tim Schmielau4e57b682005-10-30 15:03:48 -080025#include <linux/slab.h>
Peter Oberparleiter26d052b2009-07-06 17:11:22 +020026#include <linux/ctype.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
28#if 0
29#define DEBUGP printk
30#else
31#define DEBUGP(fmt, a...)
32#endif
33
Rusty Russell907b29e2010-08-11 23:04:19 -060034/* Protects all parameters, and incidentally kmalloced_param list. */
35static DEFINE_MUTEX(param_lock);
36
Rusty Russella1054322010-08-11 23:04:18 -060037/* This just allows us to keep track of which parameters are kmalloced. */
38struct kmalloced_param {
39 struct list_head list;
40 char val[];
41};
Rusty Russella1054322010-08-11 23:04:18 -060042static LIST_HEAD(kmalloced_params);
43
44static void *kmalloc_parameter(unsigned int size)
45{
46 struct kmalloced_param *p;
47
48 p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
49 if (!p)
50 return NULL;
51
Rusty Russella1054322010-08-11 23:04:18 -060052 list_add(&p->list, &kmalloced_params);
Rusty Russella1054322010-08-11 23:04:18 -060053 return p->val;
54}
55
56/* Does nothing if parameter wasn't kmalloced above. */
57static void maybe_kfree_parameter(void *param)
58{
59 struct kmalloced_param *p;
60
Rusty Russella1054322010-08-11 23:04:18 -060061 list_for_each_entry(p, &kmalloced_params, list) {
62 if (p->val == param) {
63 list_del(&p->list);
64 kfree(p);
65 break;
66 }
67 }
Rusty Russella1054322010-08-11 23:04:18 -060068}
69
Eric Sesterhennb9e20a92006-03-28 01:56:24 -080070static inline char dash2underscore(char c)
Linus Torvalds1da177e2005-04-16 15:20:36 -070071{
72 if (c == '-')
73 return '_';
74 return c;
75}
76
77static inline int parameq(const char *input, const char *paramname)
78{
79 unsigned int i;
80 for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
81 if (input[i] == '\0')
82 return 1;
83 return 0;
84}
85
86static int parse_one(char *param,
87 char *val,
Rusty Russell914dcaa2010-08-11 23:04:18 -060088 const struct kernel_param *params,
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 unsigned num_params,
90 int (*handle_unknown)(char *param, char *val))
91{
92 unsigned int i;
Rusty Russell907b29e2010-08-11 23:04:19 -060093 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070094
95 /* Find parameter */
96 for (i = 0; i < num_params; i++) {
97 if (parameq(param, params[i].name)) {
Lucas De Marchi25985ed2011-03-30 22:57:33 -030098 /* No one handled NULL, so do it here. */
Rusty Russell9bbb9e52010-08-11 23:04:12 -060099 if (!val && params[i].ops->set != param_set_bool)
Rusty Russell2e9fb992010-08-11 23:04:10 -0600100 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 DEBUGP("They are equal! Calling %p\n",
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600102 params[i].ops->set);
Rusty Russell907b29e2010-08-11 23:04:19 -0600103 mutex_lock(&param_lock);
104 err = params[i].ops->set(val, &params[i]);
105 mutex_unlock(&param_lock);
106 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 }
108 }
109
110 if (handle_unknown) {
111 DEBUGP("Unknown argument: calling %p\n", handle_unknown);
112 return handle_unknown(param, val);
113 }
114
115 DEBUGP("Unknown argument `%s'\n", param);
116 return -ENOENT;
117}
118
119/* You can use " around spaces, but can't escape ". */
120/* Hyphens and underscores equivalent in parameter names. */
121static char *next_arg(char *args, char **param, char **val)
122{
123 unsigned int i, equals = 0;
124 int in_quote = 0, quoted = 0;
125 char *next;
126
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 if (*args == '"') {
128 args++;
129 in_quote = 1;
130 quoted = 1;
131 }
132
133 for (i = 0; args[i]; i++) {
Peter Oberparleiter26d052b2009-07-06 17:11:22 +0200134 if (isspace(args[i]) && !in_quote)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 break;
136 if (equals == 0) {
137 if (args[i] == '=')
138 equals = i;
139 }
140 if (args[i] == '"')
141 in_quote = !in_quote;
142 }
143
144 *param = args;
145 if (!equals)
146 *val = NULL;
147 else {
148 args[equals] = '\0';
149 *val = args + equals + 1;
150
151 /* Don't include quotes in value. */
152 if (**val == '"') {
153 (*val)++;
154 if (args[i-1] == '"')
155 args[i-1] = '\0';
156 }
157 if (quoted && args[i-1] == '"')
158 args[i-1] = '\0';
159 }
160
161 if (args[i]) {
162 args[i] = '\0';
163 next = args + i + 1;
164 } else
165 next = args + i;
Rusty Russellf36462f2005-09-27 21:45:34 -0700166
167 /* Chew up trailing spaces. */
André Goddard Rosae7d28602009-12-14 18:01:06 -0800168 return skip_spaces(next);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169}
170
171/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
172int parse_args(const char *name,
173 char *args,
Rusty Russell914dcaa2010-08-11 23:04:18 -0600174 const struct kernel_param *params,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 unsigned num,
176 int (*unknown)(char *param, char *val))
177{
178 char *param, *val;
179
180 DEBUGP("Parsing ARGS: %s\n", args);
181
Rusty Russellf36462f2005-09-27 21:45:34 -0700182 /* Chew leading spaces */
André Goddard Rosae7d28602009-12-14 18:01:06 -0800183 args = skip_spaces(args);
Rusty Russellf36462f2005-09-27 21:45:34 -0700184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 while (*args) {
186 int ret;
Ard van Breemena416aba2007-01-05 16:36:20 -0800187 int irq_was_disabled;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188
189 args = next_arg(args, &param, &val);
Ard van Breemena416aba2007-01-05 16:36:20 -0800190 irq_was_disabled = irqs_disabled();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 ret = parse_one(param, val, params, num, unknown);
Ard van Breemena416aba2007-01-05 16:36:20 -0800192 if (irq_was_disabled && !irqs_disabled()) {
193 printk(KERN_WARNING "parse_args(): option '%s' enabled "
194 "irq's!\n", param);
195 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 switch (ret) {
197 case -ENOENT:
198 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
199 name, param);
200 return ret;
201 case -ENOSPC:
202 printk(KERN_ERR
203 "%s: `%s' too large for parameter `%s'\n",
204 name, val ?: "", param);
205 return ret;
206 case 0:
207 break;
208 default:
209 printk(KERN_ERR
210 "%s: `%s' invalid for parameter `%s'\n",
211 name, val ?: "", param);
212 return ret;
213 }
214 }
215
216 /* All parsed OK. */
217 return 0;
218}
219
220/* Lazy bastard, eh? */
221#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600222 int param_set_##name(const char *val, const struct kernel_param *kp) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 { \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 tmptype l; \
Yi Yang06b2a762008-02-08 04:21:57 -0800225 int ret; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 \
Yi Yang06b2a762008-02-08 04:21:57 -0800227 ret = strtolfn(val, 0, &l); \
Satoru Moriya81c74132011-05-26 19:38:04 -0400228 if (ret < 0 || ((type)l != l)) \
229 return ret < 0 ? ret : -EINVAL; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 *((type *)kp->arg) = l; \
231 return 0; \
232 } \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600233 int param_get_##name(char *buffer, const struct kernel_param *kp) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 { \
235 return sprintf(buffer, format, *((type *)kp->arg)); \
Rusty Russella14fe242010-08-11 23:04:11 -0600236 } \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600237 struct kernel_param_ops param_ops_##name = { \
238 .set = param_set_##name, \
239 .get = param_get_##name, \
240 }; \
Rusty Russella14fe242010-08-11 23:04:11 -0600241 EXPORT_SYMBOL(param_set_##name); \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600242 EXPORT_SYMBOL(param_get_##name); \
243 EXPORT_SYMBOL(param_ops_##name)
244
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245
Yi Yang06b2a762008-02-08 04:21:57 -0800246STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
247STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
248STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
249STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
250STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
251STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
252STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600254int param_set_charp(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 if (strlen(val) > 1024) {
257 printk(KERN_ERR "%s: string parameter too long\n",
258 kp->name);
259 return -ENOSPC;
260 }
261
Rusty Russella1054322010-08-11 23:04:18 -0600262 maybe_kfree_parameter(*(char **)kp->arg);
263
264 /* This is a hack. We can't kmalloc in early boot, and we
Rusty Russelle180a6b2009-03-31 13:05:29 -0600265 * don't need to; this mangled commandline is preserved. */
266 if (slab_is_available()) {
Rusty Russella1054322010-08-11 23:04:18 -0600267 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
Rusty Russelld553ad82009-10-29 08:56:17 -0600268 if (!*(char **)kp->arg)
Rusty Russelle180a6b2009-03-31 13:05:29 -0600269 return -ENOMEM;
Rusty Russella1054322010-08-11 23:04:18 -0600270 strcpy(*(char **)kp->arg, val);
Rusty Russelle180a6b2009-03-31 13:05:29 -0600271 } else
272 *(const char **)kp->arg = val;
273
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 return 0;
275}
Rusty Russella14fe242010-08-11 23:04:11 -0600276EXPORT_SYMBOL(param_set_charp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600278int param_get_charp(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279{
280 return sprintf(buffer, "%s", *((char **)kp->arg));
281}
Rusty Russella14fe242010-08-11 23:04:11 -0600282EXPORT_SYMBOL(param_get_charp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283
Rusty Russella1054322010-08-11 23:04:18 -0600284static void param_free_charp(void *arg)
285{
286 maybe_kfree_parameter(*((char **)arg));
287}
288
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600289struct kernel_param_ops param_ops_charp = {
290 .set = param_set_charp,
291 .get = param_get_charp,
Rusty Russella1054322010-08-11 23:04:18 -0600292 .free = param_free_charp,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600293};
294EXPORT_SYMBOL(param_ops_charp);
295
Rusty Russellfddd5202009-06-12 21:46:57 -0600296/* Actually could be a bool or an int, for historical reasons. */
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600297int param_set_bool(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298{
Rusty Russellfddd5202009-06-12 21:46:57 -0600299 bool v;
Jonathan Cameronf721a462011-04-19 12:43:47 +0100300 int ret;
Rusty Russellfddd5202009-06-12 21:46:57 -0600301
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 /* No equals means "set"... */
303 if (!val) val = "1";
304
305 /* One of =[yYnN01] */
Jonathan Cameronf721a462011-04-19 12:43:47 +0100306 ret = strtobool(val, &v);
307 if (ret)
308 return ret;
Rusty Russellfddd5202009-06-12 21:46:57 -0600309
310 if (kp->flags & KPARAM_ISBOOL)
311 *(bool *)kp->arg = v;
312 else
313 *(int *)kp->arg = v;
314 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315}
Rusty Russella14fe242010-08-11 23:04:11 -0600316EXPORT_SYMBOL(param_set_bool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600318int param_get_bool(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319{
Rusty Russellfddd5202009-06-12 21:46:57 -0600320 bool val;
321 if (kp->flags & KPARAM_ISBOOL)
322 val = *(bool *)kp->arg;
323 else
324 val = *(int *)kp->arg;
325
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 /* Y and N chosen as being relatively non-coder friendly */
Rusty Russellfddd5202009-06-12 21:46:57 -0600327 return sprintf(buffer, "%c", val ? 'Y' : 'N');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328}
Rusty Russella14fe242010-08-11 23:04:11 -0600329EXPORT_SYMBOL(param_get_bool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600331struct kernel_param_ops param_ops_bool = {
332 .set = param_set_bool,
333 .get = param_get_bool,
334};
335EXPORT_SYMBOL(param_ops_bool);
336
Rusty Russellfddd5202009-06-12 21:46:57 -0600337/* This one must be bool. */
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600338int param_set_invbool(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339{
Rusty Russellfddd5202009-06-12 21:46:57 -0600340 int ret;
341 bool boolval;
Jan Beulich22e48ea2007-10-16 23:29:34 -0700342 struct kernel_param dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343
Jan Beulich22e48ea2007-10-16 23:29:34 -0700344 dummy.arg = &boolval;
Rusty Russellfddd5202009-06-12 21:46:57 -0600345 dummy.flags = KPARAM_ISBOOL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 ret = param_set_bool(val, &dummy);
347 if (ret == 0)
Rusty Russell9a71af22009-06-12 21:46:53 -0600348 *(bool *)kp->arg = !boolval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349 return ret;
350}
Rusty Russella14fe242010-08-11 23:04:11 -0600351EXPORT_SYMBOL(param_set_invbool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600353int param_get_invbool(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354{
Rusty Russell9a71af22009-06-12 21:46:53 -0600355 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356}
Rusty Russella14fe242010-08-11 23:04:11 -0600357EXPORT_SYMBOL(param_get_invbool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600359struct kernel_param_ops param_ops_invbool = {
360 .set = param_set_invbool,
361 .get = param_get_invbool,
362};
363EXPORT_SYMBOL(param_ops_invbool);
364
Bert Wesarg9730b5b2007-05-08 00:28:50 -0700365/* We break the rule and mangle the string. */
Adrian Bunk98717282006-03-25 03:07:06 -0800366static int param_array(const char *name,
367 const char *val,
368 unsigned int min, unsigned int max,
369 void *elem, int elemsize,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600370 int (*set)(const char *, const struct kernel_param *kp),
Rusty Russell3c7d76e2009-10-29 08:56:19 -0600371 u16 flags,
Richard Knutssoneb38a992008-02-06 01:37:50 -0800372 unsigned int *num)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373{
374 int ret;
375 struct kernel_param kp;
376 char save;
377
378 /* Get the name right for errors. */
379 kp.name = name;
380 kp.arg = elem;
Rusty Russell3c7d76e2009-10-29 08:56:19 -0600381 kp.flags = flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 *num = 0;
384 /* We expect a comma-separated list of values. */
385 do {
386 int len;
387
388 if (*num == max) {
389 printk(KERN_ERR "%s: can only take %i arguments\n",
390 name, max);
391 return -EINVAL;
392 }
393 len = strcspn(val, ",");
394
395 /* nul-terminate and parse */
396 save = val[len];
397 ((char *)val)[len] = '\0';
Rusty Russell907b29e2010-08-11 23:04:19 -0600398 BUG_ON(!mutex_is_locked(&param_lock));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 ret = set(val, &kp);
400
401 if (ret != 0)
402 return ret;
403 kp.arg += elemsize;
404 val += len+1;
405 (*num)++;
406 } while (save == ',');
407
408 if (*num < min) {
409 printk(KERN_ERR "%s: needs at least %i arguments\n",
410 name, min);
411 return -EINVAL;
412 }
413 return 0;
414}
415
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600416static int param_array_set(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417{
Jan Beulich22e48ea2007-10-16 23:29:34 -0700418 const struct kparam_array *arr = kp->arr;
Bert Wesarg31143a12005-04-16 15:25:42 -0700419 unsigned int temp_num;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420
421 return param_array(kp->name, val, 1, arr->max, arr->elem,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600422 arr->elemsize, arr->ops->set, kp->flags,
Rusty Russell3c7d76e2009-10-29 08:56:19 -0600423 arr->num ?: &temp_num);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424}
425
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600426static int param_array_get(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427{
428 int i, off, ret;
Jan Beulich22e48ea2007-10-16 23:29:34 -0700429 const struct kparam_array *arr = kp->arr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 struct kernel_param p;
431
432 p = *kp;
433 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
434 if (i)
435 buffer[off++] = ',';
436 p.arg = arr->elem + arr->elemsize * i;
Rusty Russell907b29e2010-08-11 23:04:19 -0600437 BUG_ON(!mutex_is_locked(&param_lock));
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600438 ret = arr->ops->get(buffer + off, &p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439 if (ret < 0)
440 return ret;
441 off += ret;
442 }
443 buffer[off] = '\0';
444 return off;
445}
446
Rusty Russelle6df34a2010-08-11 23:04:17 -0600447static void param_array_free(void *arg)
448{
449 unsigned int i;
450 const struct kparam_array *arr = arg;
451
452 if (arr->ops->free)
453 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
454 arr->ops->free(arr->elem + arr->elemsize * i);
455}
456
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600457struct kernel_param_ops param_array_ops = {
458 .set = param_array_set,
459 .get = param_array_get,
Rusty Russelle6df34a2010-08-11 23:04:17 -0600460 .free = param_array_free,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600461};
462EXPORT_SYMBOL(param_array_ops);
463
464int param_set_copystring(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465{
Jan Beulich22e48ea2007-10-16 23:29:34 -0700466 const struct kparam_string *kps = kp->str;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467
468 if (strlen(val)+1 > kps->maxlen) {
469 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
470 kp->name, kps->maxlen-1);
471 return -ENOSPC;
472 }
473 strcpy(kps->string, val);
474 return 0;
475}
Rusty Russella14fe242010-08-11 23:04:11 -0600476EXPORT_SYMBOL(param_set_copystring);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600478int param_get_string(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479{
Jan Beulich22e48ea2007-10-16 23:29:34 -0700480 const struct kparam_string *kps = kp->str;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 return strlcpy(buffer, kps->string, kps->maxlen);
482}
Rusty Russella14fe242010-08-11 23:04:11 -0600483EXPORT_SYMBOL(param_get_string);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600485struct kernel_param_ops param_ops_string = {
486 .set = param_set_copystring,
487 .get = param_get_string,
488};
489EXPORT_SYMBOL(param_ops_string);
490
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491/* sysfs output in /sys/modules/XYZ/parameters/ */
Edward Z. Yang350f8252010-02-01 18:26:59 -0500492#define to_module_attr(n) container_of(n, struct module_attribute, attr)
493#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
495extern struct kernel_param __start___param[], __stop___param[];
496
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497struct param_attribute
498{
499 struct module_attribute mattr;
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600500 const struct kernel_param *param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501};
502
503struct module_param_attrs
504{
Rusty Russell9b473de2008-10-22 10:00:22 -0500505 unsigned int num;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 struct attribute_group grp;
507 struct param_attribute attrs[0];
508};
509
Randy Dunlapef665c12007-02-13 15:19:06 -0800510#ifdef CONFIG_SYSFS
Edward Z. Yang350f8252010-02-01 18:26:59 -0500511#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512
513static ssize_t param_attr_show(struct module_attribute *mattr,
514 struct module *mod, char *buf)
515{
516 int count;
517 struct param_attribute *attribute = to_param_attr(mattr);
518
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600519 if (!attribute->param->ops->get)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 return -EPERM;
521
Rusty Russell907b29e2010-08-11 23:04:19 -0600522 mutex_lock(&param_lock);
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600523 count = attribute->param->ops->get(buf, attribute->param);
Rusty Russell907b29e2010-08-11 23:04:19 -0600524 mutex_unlock(&param_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525 if (count > 0) {
526 strcat(buf, "\n");
527 ++count;
528 }
529 return count;
530}
531
532/* sysfs always hands a nul-terminated string in buf. We rely on that. */
533static ssize_t param_attr_store(struct module_attribute *mattr,
534 struct module *owner,
535 const char *buf, size_t len)
536{
537 int err;
538 struct param_attribute *attribute = to_param_attr(mattr);
539
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600540 if (!attribute->param->ops->set)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 return -EPERM;
542
Rusty Russell907b29e2010-08-11 23:04:19 -0600543 mutex_lock(&param_lock);
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600544 err = attribute->param->ops->set(buf, attribute->param);
Rusty Russell907b29e2010-08-11 23:04:19 -0600545 mutex_unlock(&param_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 if (!err)
547 return len;
548 return err;
549}
Randy Dunlapef665c12007-02-13 15:19:06 -0800550#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551
552#ifdef CONFIG_MODULES
553#define __modinit
554#else
555#define __modinit __init
556#endif
557
Randy Dunlapef665c12007-02-13 15:19:06 -0800558#ifdef CONFIG_SYSFS
Rusty Russell907b29e2010-08-11 23:04:19 -0600559void __kernel_param_lock(void)
560{
561 mutex_lock(&param_lock);
562}
563EXPORT_SYMBOL(__kernel_param_lock);
564
565void __kernel_param_unlock(void)
566{
567 mutex_unlock(&param_lock);
568}
569EXPORT_SYMBOL(__kernel_param_unlock);
570
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571/*
Rusty Russell9b473de2008-10-22 10:00:22 -0500572 * add_sysfs_param - add a parameter to sysfs
573 * @mk: struct module_kobject
574 * @kparam: the actual parameter definition to add to sysfs
575 * @name: name of parameter
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 *
Rusty Russell9b473de2008-10-22 10:00:22 -0500577 * Create a kobject if for a (per-module) parameter if mp NULL, and
578 * create file in sysfs. Returns an error on out of memory. Always cleans up
579 * if there's an error.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 */
Rusty Russell9b473de2008-10-22 10:00:22 -0500581static __modinit int add_sysfs_param(struct module_kobject *mk,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600582 const struct kernel_param *kp,
Rusty Russell9b473de2008-10-22 10:00:22 -0500583 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584{
Rusty Russell9b473de2008-10-22 10:00:22 -0500585 struct module_param_attrs *new;
586 struct attribute **attrs;
587 int err, num;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588
Rusty Russell9b473de2008-10-22 10:00:22 -0500589 /* We don't bother calling this with invisible parameters. */
590 BUG_ON(!kp->perm);
591
592 if (!mk->mp) {
593 num = 0;
594 attrs = NULL;
595 } else {
596 num = mk->mp->num;
597 attrs = mk->mp->grp.attrs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 }
599
Rusty Russell9b473de2008-10-22 10:00:22 -0500600 /* Enlarge. */
601 new = krealloc(mk->mp,
602 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
603 GFP_KERNEL);
604 if (!new) {
605 kfree(mk->mp);
606 err = -ENOMEM;
607 goto fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 }
Rusty Russell9b473de2008-10-22 10:00:22 -0500609 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
610 if (!attrs) {
611 err = -ENOMEM;
612 goto fail_free_new;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 }
Rusty Russell9b473de2008-10-22 10:00:22 -0500614
615 /* Sysfs wants everything zeroed. */
616 memset(new, 0, sizeof(*new));
617 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
618 memset(&attrs[num], 0, sizeof(attrs[num]));
619 new->grp.name = "parameters";
620 new->grp.attrs = attrs;
621
622 /* Tack new one on the end. */
Eric W. Biedermana07e4152010-02-11 15:23:05 -0800623 sysfs_attr_init(&new->attrs[num].mattr.attr);
Rusty Russell9b473de2008-10-22 10:00:22 -0500624 new->attrs[num].param = kp;
625 new->attrs[num].mattr.show = param_attr_show;
626 new->attrs[num].mattr.store = param_attr_store;
627 new->attrs[num].mattr.attr.name = (char *)name;
628 new->attrs[num].mattr.attr.mode = kp->perm;
629 new->num = num+1;
630
631 /* Fix up all the pointers, since krealloc can move us */
632 for (num = 0; num < new->num; num++)
633 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
634 new->grp.attrs[num] = NULL;
635
636 mk->mp = new;
637 return 0;
638
639fail_free_new:
640 kfree(new);
641fail:
642 mk->mp = NULL;
643 return err;
644}
645
Linus Torvaldsd2441182008-10-23 12:07:17 -0700646#ifdef CONFIG_MODULES
Rusty Russell9b473de2008-10-22 10:00:22 -0500647static void free_module_param_attrs(struct module_kobject *mk)
648{
649 kfree(mk->mp->grp.attrs);
650 kfree(mk->mp);
651 mk->mp = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652}
653
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654/*
655 * module_param_sysfs_setup - setup sysfs support for one module
656 * @mod: module
657 * @kparam: module parameters (array)
658 * @num_params: number of module parameters
659 *
Rusty Russell9b473de2008-10-22 10:00:22 -0500660 * Adds sysfs entries for module parameters under
661 * /sys/module/[mod->name]/parameters/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 */
663int module_param_sysfs_setup(struct module *mod,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600664 const struct kernel_param *kparam,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665 unsigned int num_params)
666{
Rusty Russell9b473de2008-10-22 10:00:22 -0500667 int i, err;
668 bool params = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669
Rusty Russell9b473de2008-10-22 10:00:22 -0500670 for (i = 0; i < num_params; i++) {
671 if (kparam[i].perm == 0)
672 continue;
673 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
674 if (err)
675 return err;
676 params = true;
677 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678
Rusty Russell9b473de2008-10-22 10:00:22 -0500679 if (!params)
680 return 0;
681
682 /* Create the param group. */
683 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
684 if (err)
685 free_module_param_attrs(&mod->mkobj);
686 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687}
688
689/*
690 * module_param_sysfs_remove - remove sysfs support for one module
691 * @mod: module
692 *
693 * Remove sysfs entries for module parameters and the corresponding
694 * kobject.
695 */
696void module_param_sysfs_remove(struct module *mod)
697{
Rusty Russell9b473de2008-10-22 10:00:22 -0500698 if (mod->mkobj.mp) {
699 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 /* We are positive that no one is using any param
701 * attrs at this point. Deallocate immediately. */
Rusty Russell9b473de2008-10-22 10:00:22 -0500702 free_module_param_attrs(&mod->mkobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 }
704}
705#endif
706
Rusty Russelle180a6b2009-03-31 13:05:29 -0600707void destroy_params(const struct kernel_param *params, unsigned num)
708{
Rusty Russelle6df34a2010-08-11 23:04:17 -0600709 unsigned int i;
710
711 for (i = 0; i < num; i++)
712 if (params[i].ops->free)
713 params[i].ops->free(params[i].arg);
Rusty Russelle180a6b2009-03-31 13:05:29 -0600714}
715
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800716static struct module_kobject * __init locate_module_kobject(const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717{
718 struct module_kobject *mk;
Rusty Russell9b473de2008-10-22 10:00:22 -0500719 struct kobject *kobj;
720 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721
Rusty Russell9b473de2008-10-22 10:00:22 -0500722 kobj = kset_find_obj(module_kset, name);
723 if (kobj) {
Rusty Russell9b473de2008-10-22 10:00:22 -0500724 mk = to_module_kobject(kobj);
Rusty Russell9b473de2008-10-22 10:00:22 -0500725 } else {
726 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
727 BUG_ON(!mk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728
Rusty Russell9b473de2008-10-22 10:00:22 -0500729 mk->mod = THIS_MODULE;
730 mk->kobj.kset = module_kset;
731 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
732 "%s", name);
733 if (err) {
734 kobject_put(&mk->kobj);
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800735 printk(KERN_ERR
736 "Module '%s' failed add to sysfs, error number %d\n",
737 name, err);
738 printk(KERN_ERR
739 "The system will be unstable now.\n");
740 return NULL;
Rusty Russell9b473de2008-10-22 10:00:22 -0500741 }
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800742
743 /* So that we hold reference in both cases. */
Rusty Russell9b473de2008-10-22 10:00:22 -0500744 kobject_get(&mk->kobj);
Greg Kroah-Hartman74c5b592007-07-30 11:26:38 -0700745 }
Rusty Russell9b473de2008-10-22 10:00:22 -0500746
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800747 return mk;
748}
749
750static void __init kernel_add_sysfs_param(const char *name,
751 struct kernel_param *kparam,
752 unsigned int name_skip)
753{
754 struct module_kobject *mk;
755 int err;
756
757 mk = locate_module_kobject(name);
758 if (!mk)
759 return;
760
761 /* We need to remove old parameters before adding more. */
762 if (mk->mp)
763 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
764
Rusty Russell9b473de2008-10-22 10:00:22 -0500765 /* These should not fail at boot. */
766 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
767 BUG_ON(err);
768 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
769 BUG_ON(err);
Kay Sieversf30c53a2007-01-15 20:22:02 +0100770 kobject_uevent(&mk->kobj, KOBJ_ADD);
Rusty Russell9b473de2008-10-22 10:00:22 -0500771 kobject_put(&mk->kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772}
773
774/*
775 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
776 *
777 * Add module_parameters to sysfs for "modules" built into the kernel.
778 *
779 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
780 * "parameter" name is stored behind a dot in kernel_param->name. So,
781 * extract the "module" name for all built-in kernel_param-eters,
Rusty Russell9b473de2008-10-22 10:00:22 -0500782 * and for all who have the same, call kernel_add_sysfs_param.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 */
784static void __init param_sysfs_builtin(void)
785{
Rusty Russell9b473de2008-10-22 10:00:22 -0500786 struct kernel_param *kp;
787 unsigned int name_len;
788 char modname[MODULE_NAME_LEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789
Rusty Russell9b473de2008-10-22 10:00:22 -0500790 for (kp = __start___param; kp < __stop___param; kp++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 char *dot;
792
Rusty Russell9b473de2008-10-22 10:00:22 -0500793 if (kp->perm == 0)
794 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795
Rusty Russell730b69d2008-10-22 10:00:22 -0500796 dot = strchr(kp->name, '.');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797 if (!dot) {
Rusty Russell67e67ce2008-10-22 10:00:23 -0500798 /* This happens for core_param() */
799 strcpy(modname, "kernel");
800 name_len = 0;
801 } else {
802 name_len = dot - kp->name + 1;
803 strlcpy(modname, kp->name, name_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804 }
Rusty Russell67e67ce2008-10-22 10:00:23 -0500805 kernel_add_sysfs_param(modname, kp, name_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807}
808
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800809ssize_t __modver_version_show(struct module_attribute *mattr,
810 struct module *mod, char *buf)
811{
812 struct module_version_attribute *vattr =
813 container_of(mattr, struct module_version_attribute, mattr);
814
815 return sprintf(buf, "%s\n", vattr->version);
816}
817
Dmitry Torokhovb4bc84282011-02-07 16:02:25 -0800818extern const struct module_version_attribute *__start___modver[];
819extern const struct module_version_attribute *__stop___modver[];
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800820
821static void __init version_sysfs_builtin(void)
822{
Dmitry Torokhovb4bc84282011-02-07 16:02:25 -0800823 const struct module_version_attribute **p;
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800824 struct module_kobject *mk;
825 int err;
826
Dmitry Torokhovb4bc84282011-02-07 16:02:25 -0800827 for (p = __start___modver; p < __stop___modver; p++) {
828 const struct module_version_attribute *vattr = *p;
829
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800830 mk = locate_module_kobject(vattr->module_name);
831 if (mk) {
832 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
833 kobject_uevent(&mk->kobj, KOBJ_ADD);
834 kobject_put(&mk->kobj);
835 }
836 }
837}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838
839/* module-related sysfs stuff */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841static ssize_t module_attr_show(struct kobject *kobj,
842 struct attribute *attr,
843 char *buf)
844{
845 struct module_attribute *attribute;
846 struct module_kobject *mk;
847 int ret;
848
849 attribute = to_module_attr(attr);
850 mk = to_module_kobject(kobj);
851
852 if (!attribute->show)
Dmitry Torokhov70f28172005-04-29 01:27:34 -0500853 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855 ret = attribute->show(attribute, mk->mod, buf);
856
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 return ret;
858}
859
860static ssize_t module_attr_store(struct kobject *kobj,
861 struct attribute *attr,
862 const char *buf, size_t len)
863{
864 struct module_attribute *attribute;
865 struct module_kobject *mk;
866 int ret;
867
868 attribute = to_module_attr(attr);
869 mk = to_module_kobject(kobj);
870
871 if (!attribute->store)
Dmitry Torokhov70f28172005-04-29 01:27:34 -0500872 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 ret = attribute->store(attribute, mk->mod, buf, len);
875
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 return ret;
877}
878
Emese Revfy52cf25d2010-01-19 02:58:23 +0100879static const struct sysfs_ops module_sysfs_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 .show = module_attr_show,
881 .store = module_attr_store,
882};
883
Kay Sievers270a6c42007-01-18 13:26:15 +0100884static int uevent_filter(struct kset *kset, struct kobject *kobj)
885{
886 struct kobj_type *ktype = get_ktype(kobj);
887
888 if (ktype == &module_ktype)
889 return 1;
890 return 0;
891}
892
Emese Revfy9cd43612009-12-31 14:52:51 +0100893static const struct kset_uevent_ops module_uevent_ops = {
Kay Sievers270a6c42007-01-18 13:26:15 +0100894 .filter = uevent_filter,
895};
896
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700897struct kset *module_kset;
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700898int module_sysfs_initialized;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700899
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700900struct kobj_type module_ktype = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901 .sysfs_ops = &module_sysfs_ops,
902};
903
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904/*
905 * param_sysfs_init - wrapper for built-in params support
906 */
907static int __init param_sysfs_init(void)
908{
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700909 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
910 if (!module_kset) {
911 printk(KERN_WARNING "%s (%d): error creating kset\n",
912 __FILE__, __LINE__);
913 return -ENOMEM;
Randy Dunlapd8c76492006-09-29 01:58:55 -0700914 }
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700915 module_sysfs_initialized = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800917 version_sysfs_builtin();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 param_sysfs_builtin();
919
920 return 0;
921}
Mark Huangd10be6d2006-09-29 01:59:34 -0700922subsys_initcall(param_sysfs_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700924#endif /* CONFIG_SYSFS */