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Thomas Gleixner1a59d1b82019-05-27 08:55:05 +02001// SPDX-License-Identifier: GPL-2.0-or-later
Linus Torvalds1da177e2005-04-16 15:20:36 -07002/* Helpers for initial module or kernel cmdline parsing
3 Copyright (C) 2001 Rusty Russell.
4
Linus Torvalds1da177e2005-04-16 15:20:36 -07005*/
Linus Torvalds1da177e2005-04-16 15:20:36 -07006#include <linux/kernel.h>
7#include <linux/string.h>
8#include <linux/errno.h>
9#include <linux/module.h>
Geert Uytterhoeven63a12d92014-10-13 15:55:44 -070010#include <linux/moduleparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/device.h>
12#include <linux/err.h>
Tim Schmielau4e57b682005-10-30 15:03:48 -080013#include <linux/slab.h>
Peter Oberparleiter26d052b2009-07-06 17:11:22 +020014#include <linux/ctype.h>
David Howells20657f62019-08-19 17:17:55 -070015#include <linux/security.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016
Rusty Russellcf2fde72015-06-26 06:44:38 +093017#ifdef CONFIG_SYSFS
Dan Streetmanb51d23e42015-06-17 06:18:52 +093018/* Protects all built-in parameters, modules use their own param_lock */
Rusty Russell907b29e2010-08-11 23:04:19 -060019static DEFINE_MUTEX(param_lock);
20
Dan Streetmanb51d23e42015-06-17 06:18:52 +093021/* Use the module's mutex, or if built-in use the built-in mutex */
Stephen Rothwell20bdc2c2015-06-26 13:19:19 +100022#ifdef CONFIG_MODULES
Dan Streetmanb51d23e42015-06-17 06:18:52 +093023#define KPARAM_MUTEX(mod) ((mod) ? &(mod)->param_lock : &param_lock)
Stephen Rothwell20bdc2c2015-06-26 13:19:19 +100024#else
25#define KPARAM_MUTEX(mod) (&param_lock)
26#endif
Rusty Russellcf2fde72015-06-26 06:44:38 +093027
28static inline void check_kparam_locked(struct module *mod)
29{
30 BUG_ON(!mutex_is_locked(KPARAM_MUTEX(mod)));
31}
32#else
33static inline void check_kparam_locked(struct module *mod)
34{
35}
36#endif /* !CONFIG_SYSFS */
Dan Streetmanb51d23e42015-06-17 06:18:52 +093037
Rusty Russella1054322010-08-11 23:04:18 -060038/* This just allows us to keep track of which parameters are kmalloced. */
39struct kmalloced_param {
40 struct list_head list;
41 char val[];
42};
Rusty Russella1054322010-08-11 23:04:18 -060043static LIST_HEAD(kmalloced_params);
Dan Streetmanb51d23e42015-06-17 06:18:52 +093044static DEFINE_SPINLOCK(kmalloced_params_lock);
Rusty Russella1054322010-08-11 23:04:18 -060045
46static void *kmalloc_parameter(unsigned int size)
47{
48 struct kmalloced_param *p;
49
50 p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
51 if (!p)
52 return NULL;
53
Dan Streetmanb51d23e42015-06-17 06:18:52 +093054 spin_lock(&kmalloced_params_lock);
Rusty Russella1054322010-08-11 23:04:18 -060055 list_add(&p->list, &kmalloced_params);
Dan Streetmanb51d23e42015-06-17 06:18:52 +093056 spin_unlock(&kmalloced_params_lock);
57
Rusty Russella1054322010-08-11 23:04:18 -060058 return p->val;
59}
60
61/* Does nothing if parameter wasn't kmalloced above. */
62static void maybe_kfree_parameter(void *param)
63{
64 struct kmalloced_param *p;
65
Dan Streetmanb51d23e42015-06-17 06:18:52 +093066 spin_lock(&kmalloced_params_lock);
Rusty Russella1054322010-08-11 23:04:18 -060067 list_for_each_entry(p, &kmalloced_params, list) {
68 if (p->val == param) {
69 list_del(&p->list);
70 kfree(p);
71 break;
72 }
73 }
Dan Streetmanb51d23e42015-06-17 06:18:52 +093074 spin_unlock(&kmalloced_params_lock);
Rusty Russella1054322010-08-11 23:04:18 -060075}
76
Michal Schmidtb1e4d202011-10-10 00:03:37 +020077static char dash2underscore(char c)
Linus Torvalds1da177e2005-04-16 15:20:36 -070078{
79 if (c == '-')
80 return '_';
81 return c;
82}
83
Michal Schmidtb1e4d202011-10-10 00:03:37 +020084bool parameqn(const char *a, const char *b, size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -070085{
Michal Schmidtb1e4d202011-10-10 00:03:37 +020086 size_t i;
87
88 for (i = 0; i < n; i++) {
89 if (dash2underscore(a[i]) != dash2underscore(b[i]))
90 return false;
91 }
92 return true;
93}
94
95bool parameq(const char *a, const char *b)
96{
97 return parameqn(a, b, strlen(a)+1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098}
99
David Howells20657f62019-08-19 17:17:55 -0700100static bool param_check_unsafe(const struct kernel_param *kp)
Rusty Russell7a486d372014-08-27 06:25:23 +0930101{
David Howells20657f62019-08-19 17:17:55 -0700102 if (kp->flags & KERNEL_PARAM_FL_HWPARAM &&
103 security_locked_down(LOCKDOWN_MODULE_PARAMETERS))
104 return false;
105
Rusty Russell7a486d372014-08-27 06:25:23 +0930106 if (kp->flags & KERNEL_PARAM_FL_UNSAFE) {
Chris Wilsonedc41b32018-04-10 16:35:18 -0700107 pr_notice("Setting dangerous option %s - tainting kernel\n",
108 kp->name);
Rusty Russell7a486d372014-08-27 06:25:23 +0930109 add_taint(TAINT_USER, LOCKDEP_STILL_OK);
110 }
David Howells20657f62019-08-19 17:17:55 -0700111
112 return true;
Rusty Russell7a486d372014-08-27 06:25:23 +0930113}
114
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115static int parse_one(char *param,
116 char *val,
Jim Cromie9fb48c72012-04-27 14:30:34 -0600117 const char *doing,
Rusty Russell914dcaa2010-08-11 23:04:18 -0600118 const struct kernel_param *params,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 unsigned num_params,
Pawel Moll026cee02012-03-26 12:50:51 +1030120 s16 min_level,
121 s16 max_level,
Luis R. Rodriguezecc86172015-03-30 16:20:03 -0700122 void *arg,
Jim Cromie9fb48c72012-04-27 14:30:34 -0600123 int (*handle_unknown)(char *param, char *val,
Luis R. Rodriguezecc86172015-03-30 16:20:03 -0700124 const char *doing, void *arg))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125{
126 unsigned int i;
Rusty Russell907b29e2010-08-11 23:04:19 -0600127 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
129 /* Find parameter */
130 for (i = 0; i < num_params; i++) {
131 if (parameq(param, params[i].name)) {
Pawel Moll026cee02012-03-26 12:50:51 +1030132 if (params[i].level < min_level
133 || params[i].level > max_level)
134 return 0;
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300135 /* No one handled NULL, so do it here. */
Steven Rostedtab013c52013-08-20 15:33:19 +0930136 if (!val &&
Jani Nikula6a4c2642014-08-27 06:21:23 +0930137 !(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG))
Rusty Russell2e9fb992010-08-11 23:04:10 -0600138 return -EINVAL;
Jim Cromie9fb48c72012-04-27 14:30:34 -0600139 pr_debug("handling %s with %p\n", param,
140 params[i].ops->set);
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930141 kernel_param_lock(params[i].mod);
David Howells20657f62019-08-19 17:17:55 -0700142 if (param_check_unsafe(&params[i]))
143 err = params[i].ops->set(val, &params[i]);
144 else
145 err = -EPERM;
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930146 kernel_param_unlock(params[i].mod);
Rusty Russell907b29e2010-08-11 23:04:19 -0600147 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 }
149 }
150
151 if (handle_unknown) {
Jim Cromie9fb48c72012-04-27 14:30:34 -0600152 pr_debug("doing %s: %s='%s'\n", doing, param, val);
Luis R. Rodriguezecc86172015-03-30 16:20:03 -0700153 return handle_unknown(param, val, doing, arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 }
155
Jim Cromie9fb48c72012-04-27 14:30:34 -0600156 pr_debug("Unknown argument '%s'\n", param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 return -ENOENT;
158}
159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
Rusty Russell51e158c2014-04-28 11:34:33 +0930161char *parse_args(const char *doing,
162 char *args,
163 const struct kernel_param *params,
164 unsigned num,
165 s16 min_level,
166 s16 max_level,
Luis R. Rodriguezecc86172015-03-30 16:20:03 -0700167 void *arg,
168 int (*unknown)(char *param, char *val,
169 const char *doing, void *arg))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170{
Oleg Nesterov74b22c42015-08-26 09:42:34 +0930171 char *param, *val, *err = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
Rusty Russellf36462f2005-09-27 21:45:34 -0700173 /* Chew leading spaces */
André Goddard Rosae7d28602009-12-14 18:01:06 -0800174 args = skip_spaces(args);
Rusty Russellf36462f2005-09-27 21:45:34 -0700175
Jim Cromie1ef9eaf2012-05-03 11:57:37 -0600176 if (*args)
Jim Cromie9fb48c72012-04-27 14:30:34 -0600177 pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 while (*args) {
180 int ret;
Ard van Breemena416aba2007-01-05 16:36:20 -0800181 int irq_was_disabled;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
183 args = next_arg(args, &param, &val);
Rusty Russell51e158c2014-04-28 11:34:33 +0930184 /* Stop at -- */
185 if (!val && strcmp(param, "--") == 0)
Oleg Nesterov74b22c42015-08-26 09:42:34 +0930186 return err ?: args;
Ard van Breemena416aba2007-01-05 16:36:20 -0800187 irq_was_disabled = irqs_disabled();
Jim Cromie9fb48c72012-04-27 14:30:34 -0600188 ret = parse_one(param, val, doing, params, num,
Luis R. Rodriguezecc86172015-03-30 16:20:03 -0700189 min_level, max_level, arg, unknown);
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600190 if (irq_was_disabled && !irqs_disabled())
191 pr_warn("%s: option '%s' enabled irq's!\n",
192 doing, param);
193
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 switch (ret) {
Oleg Nesterov74b22c42015-08-26 09:42:34 +0930195 case 0:
196 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 case -ENOENT:
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600198 pr_err("%s: Unknown parameter `%s'\n", doing, param);
Oleg Nesterov74b22c42015-08-26 09:42:34 +0930199 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 case -ENOSPC:
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600201 pr_err("%s: `%s' too large for parameter `%s'\n",
Jim Cromie9fb48c72012-04-27 14:30:34 -0600202 doing, val ?: "", param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 break;
204 default:
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600205 pr_err("%s: `%s' invalid for parameter `%s'\n",
Jim Cromie9fb48c72012-04-27 14:30:34 -0600206 doing, val ?: "", param);
Oleg Nesterov74b22c42015-08-26 09:42:34 +0930207 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 }
Oleg Nesterov74b22c42015-08-26 09:42:34 +0930209
210 err = ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 }
212
Oleg Nesterov74b22c42015-08-26 09:42:34 +0930213 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214}
215
216/* Lazy bastard, eh? */
Felipe Contreras88a88b322013-12-04 14:09:38 +1030217#define STANDARD_PARAM_DEF(name, type, format, strtolfn) \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600218 int param_set_##name(const char *val, const struct kernel_param *kp) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 { \
Felipe Contreras88a88b322013-12-04 14:09:38 +1030220 return strtolfn(val, 0, (type *)kp->arg); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 } \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600222 int param_get_##name(char *buffer, const struct kernel_param *kp) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 { \
Jean Delvare96802e62017-10-03 16:16:38 -0700224 return scnprintf(buffer, PAGE_SIZE, format "\n", \
Chen Gangf4940ab2013-08-20 15:35:04 +0930225 *((type *)kp->arg)); \
Rusty Russella14fe242010-08-11 23:04:11 -0600226 } \
Luis R. Rodriguez9c278472015-05-27 11:09:38 +0930227 const struct kernel_param_ops param_ops_##name = { \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600228 .set = param_set_##name, \
229 .get = param_get_##name, \
230 }; \
Rusty Russella14fe242010-08-11 23:04:11 -0600231 EXPORT_SYMBOL(param_set_##name); \
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600232 EXPORT_SYMBOL(param_get_##name); \
233 EXPORT_SYMBOL(param_ops_##name)
234
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235
Jean Delvaree0596c82017-10-03 16:16:41 -0700236STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8);
237STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16);
238STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16);
239STANDARD_PARAM_DEF(int, int, "%i", kstrtoint);
240STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint);
241STANDARD_PARAM_DEF(long, long, "%li", kstrtol);
242STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul);
243STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600245int param_set_charp(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 if (strlen(val) > 1024) {
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600248 pr_err("%s: string parameter too long\n", kp->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 return -ENOSPC;
250 }
251
Rusty Russella1054322010-08-11 23:04:18 -0600252 maybe_kfree_parameter(*(char **)kp->arg);
253
254 /* This is a hack. We can't kmalloc in early boot, and we
Rusty Russelle180a6b2009-03-31 13:05:29 -0600255 * don't need to; this mangled commandline is preserved. */
256 if (slab_is_available()) {
Rusty Russella1054322010-08-11 23:04:18 -0600257 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
Rusty Russelld553ad82009-10-29 08:56:17 -0600258 if (!*(char **)kp->arg)
Rusty Russelle180a6b2009-03-31 13:05:29 -0600259 return -ENOMEM;
Rusty Russella1054322010-08-11 23:04:18 -0600260 strcpy(*(char **)kp->arg, val);
Rusty Russelle180a6b2009-03-31 13:05:29 -0600261 } else
262 *(const char **)kp->arg = val;
263
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 return 0;
265}
Rusty Russella14fe242010-08-11 23:04:11 -0600266EXPORT_SYMBOL(param_set_charp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600268int param_get_charp(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269{
Jean Delvare96802e62017-10-03 16:16:38 -0700270 return scnprintf(buffer, PAGE_SIZE, "%s\n", *((char **)kp->arg));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271}
Rusty Russella14fe242010-08-11 23:04:11 -0600272EXPORT_SYMBOL(param_get_charp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273
Dan Streetman3d9c6372015-11-06 16:29:12 -0800274void param_free_charp(void *arg)
Rusty Russella1054322010-08-11 23:04:18 -0600275{
276 maybe_kfree_parameter(*((char **)arg));
277}
Dan Streetman3d9c6372015-11-06 16:29:12 -0800278EXPORT_SYMBOL(param_free_charp);
Rusty Russella1054322010-08-11 23:04:18 -0600279
Luis R. Rodriguez9c278472015-05-27 11:09:38 +0930280const struct kernel_param_ops param_ops_charp = {
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600281 .set = param_set_charp,
282 .get = param_get_charp,
Rusty Russella1054322010-08-11 23:04:18 -0600283 .free = param_free_charp,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600284};
285EXPORT_SYMBOL(param_ops_charp);
286
Rusty Russellfddd5202009-06-12 21:46:57 -0600287/* Actually could be a bool or an int, for historical reasons. */
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600288int param_set_bool(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289{
290 /* No equals means "set"... */
291 if (!val) val = "1";
292
293 /* One of =[yYnN01] */
Rusty Russell8b8252812012-03-26 12:50:51 +1030294 return strtobool(val, kp->arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295}
Rusty Russella14fe242010-08-11 23:04:11 -0600296EXPORT_SYMBOL(param_set_bool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600298int param_get_bool(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299{
300 /* Y and N chosen as being relatively non-coder friendly */
Jean Delvare96802e62017-10-03 16:16:38 -0700301 return sprintf(buffer, "%c\n", *(bool *)kp->arg ? 'Y' : 'N');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302}
Rusty Russella14fe242010-08-11 23:04:11 -0600303EXPORT_SYMBOL(param_get_bool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304
Luis R. Rodriguez9c278472015-05-27 11:09:38 +0930305const struct kernel_param_ops param_ops_bool = {
Jani Nikula6a4c2642014-08-27 06:21:23 +0930306 .flags = KERNEL_PARAM_OPS_FL_NOARG,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600307 .set = param_set_bool,
308 .get = param_get_bool,
309};
310EXPORT_SYMBOL(param_ops_bool);
311
Luis R. Rodriguezd19f05d2015-05-27 11:09:38 +0930312int param_set_bool_enable_only(const char *val, const struct kernel_param *kp)
313{
314 int err = 0;
315 bool new_value;
316 bool orig_value = *(bool *)kp->arg;
317 struct kernel_param dummy_kp = *kp;
318
319 dummy_kp.arg = &new_value;
320
321 err = param_set_bool(val, &dummy_kp);
322 if (err)
323 return err;
324
325 /* Don't let them unset it once it's set! */
326 if (!new_value && orig_value)
327 return -EROFS;
328
329 if (new_value)
330 err = param_set_bool(val, kp);
331
332 return err;
333}
334EXPORT_SYMBOL_GPL(param_set_bool_enable_only);
335
336const struct kernel_param_ops param_ops_bool_enable_only = {
337 .flags = KERNEL_PARAM_OPS_FL_NOARG,
338 .set = param_set_bool_enable_only,
339 .get = param_get_bool,
340};
Luis R. Rodriguez154be212015-05-27 11:09:39 +0930341EXPORT_SYMBOL_GPL(param_ops_bool_enable_only);
Luis R. Rodriguezd19f05d2015-05-27 11:09:38 +0930342
Rusty Russellfddd5202009-06-12 21:46:57 -0600343/* This one must be bool. */
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600344int param_set_invbool(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345{
Rusty Russellfddd5202009-06-12 21:46:57 -0600346 int ret;
347 bool boolval;
Jan Beulich22e48ea2007-10-16 23:29:34 -0700348 struct kernel_param dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349
Jan Beulich22e48ea2007-10-16 23:29:34 -0700350 dummy.arg = &boolval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 ret = param_set_bool(val, &dummy);
352 if (ret == 0)
Rusty Russell9a71af22009-06-12 21:46:53 -0600353 *(bool *)kp->arg = !boolval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 return ret;
355}
Rusty Russella14fe242010-08-11 23:04:11 -0600356EXPORT_SYMBOL(param_set_invbool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600358int param_get_invbool(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359{
Jean Delvare96802e62017-10-03 16:16:38 -0700360 return sprintf(buffer, "%c\n", (*(bool *)kp->arg) ? 'N' : 'Y');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361}
Rusty Russella14fe242010-08-11 23:04:11 -0600362EXPORT_SYMBOL(param_get_invbool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363
Luis R. Rodriguez9c278472015-05-27 11:09:38 +0930364const struct kernel_param_ops param_ops_invbool = {
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600365 .set = param_set_invbool,
366 .get = param_get_invbool,
367};
368EXPORT_SYMBOL(param_ops_invbool);
369
Rusty Russell69116f22012-01-13 09:32:17 +1030370int param_set_bint(const char *val, const struct kernel_param *kp)
371{
Dan Streetman5104b7d2015-06-17 06:17:52 +0930372 /* Match bool exactly, by re-using it. */
373 struct kernel_param boolkp = *kp;
Rusty Russell69116f22012-01-13 09:32:17 +1030374 bool v;
375 int ret;
376
Rusty Russell69116f22012-01-13 09:32:17 +1030377 boolkp.arg = &v;
Rusty Russell69116f22012-01-13 09:32:17 +1030378
379 ret = param_set_bool(val, &boolkp);
380 if (ret == 0)
381 *(int *)kp->arg = v;
382 return ret;
383}
384EXPORT_SYMBOL(param_set_bint);
385
Luis R. Rodriguez9c278472015-05-27 11:09:38 +0930386const struct kernel_param_ops param_ops_bint = {
Jani Nikula6a4c2642014-08-27 06:21:23 +0930387 .flags = KERNEL_PARAM_OPS_FL_NOARG,
Rusty Russell69116f22012-01-13 09:32:17 +1030388 .set = param_set_bint,
389 .get = param_get_int,
390};
391EXPORT_SYMBOL(param_ops_bint);
392
Bert Wesarg9730b5b2007-05-08 00:28:50 -0700393/* We break the rule and mangle the string. */
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930394static int param_array(struct module *mod,
395 const char *name,
Adrian Bunk98717282006-03-25 03:07:06 -0800396 const char *val,
397 unsigned int min, unsigned int max,
398 void *elem, int elemsize,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600399 int (*set)(const char *, const struct kernel_param *kp),
Pawel Moll026cee02012-03-26 12:50:51 +1030400 s16 level,
Richard Knutssoneb38a992008-02-06 01:37:50 -0800401 unsigned int *num)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402{
403 int ret;
404 struct kernel_param kp;
405 char save;
406
407 /* Get the name right for errors. */
408 kp.name = name;
409 kp.arg = elem;
Pawel Moll026cee02012-03-26 12:50:51 +1030410 kp.level = level;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 *num = 0;
413 /* We expect a comma-separated list of values. */
414 do {
415 int len;
416
417 if (*num == max) {
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600418 pr_err("%s: can only take %i arguments\n", name, max);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 return -EINVAL;
420 }
421 len = strcspn(val, ",");
422
423 /* nul-terminate and parse */
424 save = val[len];
425 ((char *)val)[len] = '\0';
Rusty Russellcf2fde72015-06-26 06:44:38 +0930426 check_kparam_locked(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 ret = set(val, &kp);
428
429 if (ret != 0)
430 return ret;
431 kp.arg += elemsize;
432 val += len+1;
433 (*num)++;
434 } while (save == ',');
435
436 if (*num < min) {
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600437 pr_err("%s: needs at least %i arguments\n", name, min);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 return -EINVAL;
439 }
440 return 0;
441}
442
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600443static int param_array_set(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444{
Jan Beulich22e48ea2007-10-16 23:29:34 -0700445 const struct kparam_array *arr = kp->arr;
Bert Wesarg31143a12005-04-16 15:25:42 -0700446 unsigned int temp_num;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930448 return param_array(kp->mod, kp->name, val, 1, arr->max, arr->elem,
Pawel Moll026cee02012-03-26 12:50:51 +1030449 arr->elemsize, arr->ops->set, kp->level,
Rusty Russell3c7d76e2009-10-29 08:56:19 -0600450 arr->num ?: &temp_num);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451}
452
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600453static int param_array_get(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454{
455 int i, off, ret;
Jan Beulich22e48ea2007-10-16 23:29:34 -0700456 const struct kparam_array *arr = kp->arr;
Dan Streetman5104b7d2015-06-17 06:17:52 +0930457 struct kernel_param p = *kp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
Jean Delvare96802e62017-10-03 16:16:38 -0700460 /* Replace \n with comma */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 if (i)
Jean Delvare96802e62017-10-03 16:16:38 -0700462 buffer[off - 1] = ',';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 p.arg = arr->elem + arr->elemsize * i;
Rusty Russellcf2fde72015-06-26 06:44:38 +0930464 check_kparam_locked(p.mod);
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600465 ret = arr->ops->get(buffer + off, &p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 if (ret < 0)
467 return ret;
468 off += ret;
469 }
470 buffer[off] = '\0';
471 return off;
472}
473
Rusty Russelle6df34a2010-08-11 23:04:17 -0600474static void param_array_free(void *arg)
475{
476 unsigned int i;
477 const struct kparam_array *arr = arg;
478
479 if (arr->ops->free)
480 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
481 arr->ops->free(arr->elem + arr->elemsize * i);
482}
483
Luis R. Rodriguez9c278472015-05-27 11:09:38 +0930484const struct kernel_param_ops param_array_ops = {
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600485 .set = param_array_set,
486 .get = param_array_get,
Rusty Russelle6df34a2010-08-11 23:04:17 -0600487 .free = param_array_free,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600488};
489EXPORT_SYMBOL(param_array_ops);
490
491int param_set_copystring(const char *val, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492{
Jan Beulich22e48ea2007-10-16 23:29:34 -0700493 const struct kparam_string *kps = kp->str;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
495 if (strlen(val)+1 > kps->maxlen) {
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600496 pr_err("%s: string doesn't fit in %u chars.\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 kp->name, kps->maxlen-1);
498 return -ENOSPC;
499 }
500 strcpy(kps->string, val);
501 return 0;
502}
Rusty Russella14fe242010-08-11 23:04:11 -0600503EXPORT_SYMBOL(param_set_copystring);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600505int param_get_string(char *buffer, const struct kernel_param *kp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506{
Jan Beulich22e48ea2007-10-16 23:29:34 -0700507 const struct kparam_string *kps = kp->str;
Jean Delvare96802e62017-10-03 16:16:38 -0700508 return scnprintf(buffer, PAGE_SIZE, "%s\n", kps->string);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509}
Rusty Russella14fe242010-08-11 23:04:11 -0600510EXPORT_SYMBOL(param_get_string);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511
Luis R. Rodriguez9c278472015-05-27 11:09:38 +0930512const struct kernel_param_ops param_ops_string = {
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600513 .set = param_set_copystring,
514 .get = param_get_string,
515};
516EXPORT_SYMBOL(param_ops_string);
517
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518/* sysfs output in /sys/modules/XYZ/parameters/ */
Edward Z. Yang350f8252010-02-01 18:26:59 -0500519#define to_module_attr(n) container_of(n, struct module_attribute, attr)
520#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522struct param_attribute
523{
524 struct module_attribute mattr;
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600525 const struct kernel_param *param;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526};
527
528struct module_param_attrs
529{
Rusty Russell9b473de2008-10-22 10:00:22 -0500530 unsigned int num;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 struct attribute_group grp;
532 struct param_attribute attrs[0];
533};
534
Randy Dunlapef665c12007-02-13 15:19:06 -0800535#ifdef CONFIG_SYSFS
Edward Z. Yang350f8252010-02-01 18:26:59 -0500536#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537
538static ssize_t param_attr_show(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +0930539 struct module_kobject *mk, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540{
541 int count;
542 struct param_attribute *attribute = to_param_attr(mattr);
543
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600544 if (!attribute->param->ops->get)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 return -EPERM;
546
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930547 kernel_param_lock(mk->mod);
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600548 count = attribute->param->ops->get(buf, attribute->param);
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930549 kernel_param_unlock(mk->mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 return count;
551}
552
553/* sysfs always hands a nul-terminated string in buf. We rely on that. */
554static ssize_t param_attr_store(struct module_attribute *mattr,
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930555 struct module_kobject *mk,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 const char *buf, size_t len)
557{
558 int err;
559 struct param_attribute *attribute = to_param_attr(mattr);
560
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600561 if (!attribute->param->ops->set)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 return -EPERM;
563
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930564 kernel_param_lock(mk->mod);
David Howells20657f62019-08-19 17:17:55 -0700565 if (param_check_unsafe(attribute->param))
566 err = attribute->param->ops->set(buf, attribute->param);
567 else
568 err = -EPERM;
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930569 kernel_param_unlock(mk->mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 if (!err)
571 return len;
572 return err;
573}
Randy Dunlapef665c12007-02-13 15:19:06 -0800574#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575
576#ifdef CONFIG_MODULES
577#define __modinit
578#else
579#define __modinit __init
580#endif
581
Randy Dunlapef665c12007-02-13 15:19:06 -0800582#ifdef CONFIG_SYSFS
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930583void kernel_param_lock(struct module *mod)
Rusty Russell907b29e2010-08-11 23:04:19 -0600584{
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930585 mutex_lock(KPARAM_MUTEX(mod));
Rusty Russell907b29e2010-08-11 23:04:19 -0600586}
Rusty Russell907b29e2010-08-11 23:04:19 -0600587
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930588void kernel_param_unlock(struct module *mod)
Rusty Russell907b29e2010-08-11 23:04:19 -0600589{
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930590 mutex_unlock(KPARAM_MUTEX(mod));
Rusty Russell907b29e2010-08-11 23:04:19 -0600591}
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930592
Dan Streetmanb51d23e42015-06-17 06:18:52 +0930593EXPORT_SYMBOL(kernel_param_lock);
594EXPORT_SYMBOL(kernel_param_unlock);
Rusty Russell907b29e2010-08-11 23:04:19 -0600595
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596/*
Rusty Russell9b473de2008-10-22 10:00:22 -0500597 * add_sysfs_param - add a parameter to sysfs
598 * @mk: struct module_kobject
Jean Delvare630cc2b2017-10-03 16:14:18 -0700599 * @kp: the actual parameter definition to add to sysfs
Rusty Russell9b473de2008-10-22 10:00:22 -0500600 * @name: name of parameter
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 *
Rusty Russell9b473de2008-10-22 10:00:22 -0500602 * Create a kobject if for a (per-module) parameter if mp NULL, and
603 * create file in sysfs. Returns an error on out of memory. Always cleans up
604 * if there's an error.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 */
Rusty Russell9b473de2008-10-22 10:00:22 -0500606static __modinit int add_sysfs_param(struct module_kobject *mk,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600607 const struct kernel_param *kp,
Rusty Russell9b473de2008-10-22 10:00:22 -0500608 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609{
Rusty Russell18eb74f2014-11-10 09:32:29 +1030610 struct module_param_attrs *new_mp;
611 struct attribute **new_attrs;
612 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613
Rusty Russell9b473de2008-10-22 10:00:22 -0500614 /* We don't bother calling this with invisible parameters. */
615 BUG_ON(!kp->perm);
616
617 if (!mk->mp) {
Rusty Russell18eb74f2014-11-10 09:32:29 +1030618 /* First allocation. */
619 mk->mp = kzalloc(sizeof(*mk->mp), GFP_KERNEL);
620 if (!mk->mp)
621 return -ENOMEM;
622 mk->mp->grp.name = "parameters";
623 /* NULL-terminated attribute array. */
624 mk->mp->grp.attrs = kzalloc(sizeof(mk->mp->grp.attrs[0]),
625 GFP_KERNEL);
626 /* Caller will cleanup via free_module_param_attrs */
627 if (!mk->mp->grp.attrs)
628 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 }
630
Rusty Russell18eb74f2014-11-10 09:32:29 +1030631 /* Enlarge allocations. */
632 new_mp = krealloc(mk->mp,
633 sizeof(*mk->mp) +
634 sizeof(mk->mp->attrs[0]) * (mk->mp->num + 1),
635 GFP_KERNEL);
636 if (!new_mp)
637 return -ENOMEM;
638 mk->mp = new_mp;
Rusty Russell9b473de2008-10-22 10:00:22 -0500639
Rusty Russell18eb74f2014-11-10 09:32:29 +1030640 /* Extra pointer for NULL terminator */
641 new_attrs = krealloc(mk->mp->grp.attrs,
642 sizeof(mk->mp->grp.attrs[0]) * (mk->mp->num + 2),
643 GFP_KERNEL);
644 if (!new_attrs)
645 return -ENOMEM;
646 mk->mp->grp.attrs = new_attrs;
Rusty Russell9b473de2008-10-22 10:00:22 -0500647
648 /* Tack new one on the end. */
Rusty Russellc772be52015-01-20 09:07:04 +1030649 memset(&mk->mp->attrs[mk->mp->num], 0, sizeof(mk->mp->attrs[0]));
Rusty Russell18eb74f2014-11-10 09:32:29 +1030650 sysfs_attr_init(&mk->mp->attrs[mk->mp->num].mattr.attr);
651 mk->mp->attrs[mk->mp->num].param = kp;
652 mk->mp->attrs[mk->mp->num].mattr.show = param_attr_show;
Kees Cookb0a65b02014-12-12 13:36:49 +1030653 /* Do not allow runtime DAC changes to make param writable. */
654 if ((kp->perm & (S_IWUSR | S_IWGRP | S_IWOTH)) != 0)
655 mk->mp->attrs[mk->mp->num].mattr.store = param_attr_store;
Rusty Russell574732c2014-12-23 15:05:36 +1030656 else
657 mk->mp->attrs[mk->mp->num].mattr.store = NULL;
Rusty Russell18eb74f2014-11-10 09:32:29 +1030658 mk->mp->attrs[mk->mp->num].mattr.attr.name = (char *)name;
659 mk->mp->attrs[mk->mp->num].mattr.attr.mode = kp->perm;
660 mk->mp->num++;
Rusty Russell9b473de2008-10-22 10:00:22 -0500661
662 /* Fix up all the pointers, since krealloc can move us */
Rusty Russell18eb74f2014-11-10 09:32:29 +1030663 for (i = 0; i < mk->mp->num; i++)
664 mk->mp->grp.attrs[i] = &mk->mp->attrs[i].mattr.attr;
665 mk->mp->grp.attrs[mk->mp->num] = NULL;
Rusty Russell9b473de2008-10-22 10:00:22 -0500666 return 0;
Rusty Russell9b473de2008-10-22 10:00:22 -0500667}
668
Linus Torvaldsd2441182008-10-23 12:07:17 -0700669#ifdef CONFIG_MODULES
Rusty Russell9b473de2008-10-22 10:00:22 -0500670static void free_module_param_attrs(struct module_kobject *mk)
671{
Rusty Russell18eb74f2014-11-10 09:32:29 +1030672 if (mk->mp)
673 kfree(mk->mp->grp.attrs);
Rusty Russell9b473de2008-10-22 10:00:22 -0500674 kfree(mk->mp);
675 mk->mp = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676}
677
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678/*
679 * module_param_sysfs_setup - setup sysfs support for one module
680 * @mod: module
681 * @kparam: module parameters (array)
682 * @num_params: number of module parameters
683 *
Rusty Russell9b473de2008-10-22 10:00:22 -0500684 * Adds sysfs entries for module parameters under
685 * /sys/module/[mod->name]/parameters/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 */
687int module_param_sysfs_setup(struct module *mod,
Rusty Russell9bbb9e52010-08-11 23:04:12 -0600688 const struct kernel_param *kparam,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 unsigned int num_params)
690{
Rusty Russell9b473de2008-10-22 10:00:22 -0500691 int i, err;
692 bool params = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693
Rusty Russell9b473de2008-10-22 10:00:22 -0500694 for (i = 0; i < num_params; i++) {
695 if (kparam[i].perm == 0)
696 continue;
697 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
Rusty Russell18eb74f2014-11-10 09:32:29 +1030698 if (err) {
699 free_module_param_attrs(&mod->mkobj);
Rusty Russell9b473de2008-10-22 10:00:22 -0500700 return err;
Rusty Russell18eb74f2014-11-10 09:32:29 +1030701 }
Rusty Russell9b473de2008-10-22 10:00:22 -0500702 params = true;
703 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704
Rusty Russell9b473de2008-10-22 10:00:22 -0500705 if (!params)
706 return 0;
707
708 /* Create the param group. */
709 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
710 if (err)
711 free_module_param_attrs(&mod->mkobj);
712 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713}
714
715/*
716 * module_param_sysfs_remove - remove sysfs support for one module
717 * @mod: module
718 *
719 * Remove sysfs entries for module parameters and the corresponding
720 * kobject.
721 */
722void module_param_sysfs_remove(struct module *mod)
723{
Rusty Russell9b473de2008-10-22 10:00:22 -0500724 if (mod->mkobj.mp) {
725 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 /* We are positive that no one is using any param
727 * attrs at this point. Deallocate immediately. */
Rusty Russell9b473de2008-10-22 10:00:22 -0500728 free_module_param_attrs(&mod->mkobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 }
730}
731#endif
732
Rusty Russelle180a6b2009-03-31 13:05:29 -0600733void destroy_params(const struct kernel_param *params, unsigned num)
734{
Rusty Russelle6df34a2010-08-11 23:04:17 -0600735 unsigned int i;
736
737 for (i = 0; i < num; i++)
738 if (params[i].ops->free)
739 params[i].ops->free(params[i].arg);
Rusty Russelle180a6b2009-03-31 13:05:29 -0600740}
741
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800742static struct module_kobject * __init locate_module_kobject(const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743{
744 struct module_kobject *mk;
Rusty Russell9b473de2008-10-22 10:00:22 -0500745 struct kobject *kobj;
746 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
Rusty Russell9b473de2008-10-22 10:00:22 -0500748 kobj = kset_find_obj(module_kset, name);
749 if (kobj) {
Rusty Russell9b473de2008-10-22 10:00:22 -0500750 mk = to_module_kobject(kobj);
Rusty Russell9b473de2008-10-22 10:00:22 -0500751 } else {
752 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
753 BUG_ON(!mk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754
Rusty Russell9b473de2008-10-22 10:00:22 -0500755 mk->mod = THIS_MODULE;
756 mk->kobj.kset = module_kset;
757 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
758 "%s", name);
Kay Sievers88bfa322011-07-24 22:06:04 +0930759#ifdef CONFIG_MODULES
760 if (!err)
761 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
762#endif
Rusty Russell9b473de2008-10-22 10:00:22 -0500763 if (err) {
764 kobject_put(&mk->kobj);
Jim Cromieb5f3abf2012-05-03 18:22:44 -0600765 pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n",
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800766 name, err);
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800767 return NULL;
Rusty Russell9b473de2008-10-22 10:00:22 -0500768 }
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800769
770 /* So that we hold reference in both cases. */
Rusty Russell9b473de2008-10-22 10:00:22 -0500771 kobject_get(&mk->kobj);
Greg Kroah-Hartman74c5b592007-07-30 11:26:38 -0700772 }
Rusty Russell9b473de2008-10-22 10:00:22 -0500773
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800774 return mk;
775}
776
777static void __init kernel_add_sysfs_param(const char *name,
Geert Uytterhoeven63a12d92014-10-13 15:55:44 -0700778 const struct kernel_param *kparam,
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800779 unsigned int name_skip)
780{
781 struct module_kobject *mk;
782 int err;
783
784 mk = locate_module_kobject(name);
785 if (!mk)
786 return;
787
788 /* We need to remove old parameters before adding more. */
789 if (mk->mp)
790 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
791
Rusty Russell9b473de2008-10-22 10:00:22 -0500792 /* These should not fail at boot. */
793 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
794 BUG_ON(err);
795 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
796 BUG_ON(err);
Kay Sieversf30c53a2007-01-15 20:22:02 +0100797 kobject_uevent(&mk->kobj, KOBJ_ADD);
Rusty Russell9b473de2008-10-22 10:00:22 -0500798 kobject_put(&mk->kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799}
800
801/*
Jean Delvareb634d132013-07-02 15:35:11 +0930802 * param_sysfs_builtin - add sysfs parameters for built-in modules
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803 *
804 * Add module_parameters to sysfs for "modules" built into the kernel.
805 *
806 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
807 * "parameter" name is stored behind a dot in kernel_param->name. So,
808 * extract the "module" name for all built-in kernel_param-eters,
Rusty Russell9b473de2008-10-22 10:00:22 -0500809 * and for all who have the same, call kernel_add_sysfs_param.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 */
811static void __init param_sysfs_builtin(void)
812{
Geert Uytterhoeven63a12d92014-10-13 15:55:44 -0700813 const struct kernel_param *kp;
Rusty Russell9b473de2008-10-22 10:00:22 -0500814 unsigned int name_len;
815 char modname[MODULE_NAME_LEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816
Rusty Russell9b473de2008-10-22 10:00:22 -0500817 for (kp = __start___param; kp < __stop___param; kp++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 char *dot;
819
Rusty Russell9b473de2008-10-22 10:00:22 -0500820 if (kp->perm == 0)
821 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822
Rusty Russell730b69d2008-10-22 10:00:22 -0500823 dot = strchr(kp->name, '.');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824 if (!dot) {
Rusty Russell67e67ce2008-10-22 10:00:23 -0500825 /* This happens for core_param() */
826 strcpy(modname, "kernel");
827 name_len = 0;
828 } else {
829 name_len = dot - kp->name + 1;
830 strlcpy(modname, kp->name, name_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 }
Rusty Russell67e67ce2008-10-22 10:00:23 -0500832 kernel_add_sysfs_param(modname, kp, name_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834}
835
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800836ssize_t __modver_version_show(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +0930837 struct module_kobject *mk, char *buf)
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800838{
839 struct module_version_attribute *vattr =
840 container_of(mattr, struct module_version_attribute, mattr);
841
Chen Gangf4940ab2013-08-20 15:35:04 +0930842 return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800843}
844
Dmitry Torokhovb4bc84282011-02-07 16:02:25 -0800845extern const struct module_version_attribute *__start___modver[];
846extern const struct module_version_attribute *__stop___modver[];
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800847
848static void __init version_sysfs_builtin(void)
849{
Dmitry Torokhovb4bc84282011-02-07 16:02:25 -0800850 const struct module_version_attribute **p;
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800851 struct module_kobject *mk;
852 int err;
853
Dmitry Torokhovb4bc84282011-02-07 16:02:25 -0800854 for (p = __start___modver; p < __stop___modver; p++) {
855 const struct module_version_attribute *vattr = *p;
856
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800857 mk = locate_module_kobject(vattr->module_name);
858 if (mk) {
859 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
Rusty Russell74c3dea32015-06-17 06:16:52 +0930860 WARN_ON_ONCE(err);
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800861 kobject_uevent(&mk->kobj, KOBJ_ADD);
862 kobject_put(&mk->kobj);
863 }
864 }
865}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866
867/* module-related sysfs stuff */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869static ssize_t module_attr_show(struct kobject *kobj,
870 struct attribute *attr,
871 char *buf)
872{
873 struct module_attribute *attribute;
874 struct module_kobject *mk;
875 int ret;
876
877 attribute = to_module_attr(attr);
878 mk = to_module_kobject(kobj);
879
880 if (!attribute->show)
Dmitry Torokhov70f28172005-04-29 01:27:34 -0500881 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882
Kay Sievers4befb022011-07-24 22:06:04 +0930883 ret = attribute->show(attribute, mk, buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 return ret;
886}
887
888static ssize_t module_attr_store(struct kobject *kobj,
889 struct attribute *attr,
890 const char *buf, size_t len)
891{
892 struct module_attribute *attribute;
893 struct module_kobject *mk;
894 int ret;
895
896 attribute = to_module_attr(attr);
897 mk = to_module_kobject(kobj);
898
899 if (!attribute->store)
Dmitry Torokhov70f28172005-04-29 01:27:34 -0500900 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901
Kay Sievers4befb022011-07-24 22:06:04 +0930902 ret = attribute->store(attribute, mk, buf, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904 return ret;
905}
906
Emese Revfy52cf25d2010-01-19 02:58:23 +0100907static const struct sysfs_ops module_sysfs_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908 .show = module_attr_show,
909 .store = module_attr_store,
910};
911
Kay Sievers270a6c42007-01-18 13:26:15 +0100912static int uevent_filter(struct kset *kset, struct kobject *kobj)
913{
914 struct kobj_type *ktype = get_ktype(kobj);
915
916 if (ktype == &module_ktype)
917 return 1;
918 return 0;
919}
920
Emese Revfy9cd43612009-12-31 14:52:51 +0100921static const struct kset_uevent_ops module_uevent_ops = {
Kay Sievers270a6c42007-01-18 13:26:15 +0100922 .filter = uevent_filter,
923};
924
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700925struct kset *module_kset;
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700926int module_sysfs_initialized;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927
Li Zhong942e4432013-09-03 16:33:57 +0930928static void module_kobj_release(struct kobject *kobj)
929{
930 struct module_kobject *mk = to_module_kobject(kobj);
931 complete(mk->kobj_completion);
932}
933
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700934struct kobj_type module_ktype = {
Li Zhong942e4432013-09-03 16:33:57 +0930935 .release = module_kobj_release,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 .sysfs_ops = &module_sysfs_ops,
937};
938
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939/*
940 * param_sysfs_init - wrapper for built-in params support
941 */
942static int __init param_sysfs_init(void)
943{
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700944 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
945 if (!module_kset) {
946 printk(KERN_WARNING "%s (%d): error creating kset\n",
947 __FILE__, __LINE__);
948 return -ENOMEM;
Randy Dunlapd8c76492006-09-29 01:58:55 -0700949 }
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -0700950 module_sysfs_initialized = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700951
Dmitry Torokhove94965e2010-12-15 14:00:19 -0800952 version_sysfs_builtin();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953 param_sysfs_builtin();
954
955 return 0;
956}
Mark Huangd10be6d2006-09-29 01:59:34 -0700957subsys_initcall(param_sysfs_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700958
Greg Kroah-Hartman7405c1e2007-11-01 10:39:50 -0700959#endif /* CONFIG_SYSFS */