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-rw-r--r--kernel/params.c233
1 files changed, 161 insertions, 72 deletions
diff --git a/kernel/params.c b/kernel/params.c
index 0b30ecd53a52..08107d181758 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -31,6 +31,42 @@
31#define DEBUGP(fmt, a...) 31#define DEBUGP(fmt, a...)
32#endif 32#endif
33 33
34/* Protects all parameters, and incidentally kmalloced_param list. */
35static DEFINE_MUTEX(param_lock);
36
37/* This just allows us to keep track of which parameters are kmalloced. */
38struct kmalloced_param {
39 struct list_head list;
40 char val[];
41};
42static 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
52 list_add(&p->list, &kmalloced_params);
53 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
61 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 }
68}
69
34static inline char dash2underscore(char c) 70static inline char dash2underscore(char c)
35{ 71{
36 if (c == '-') 72 if (c == '-')
@@ -49,18 +85,25 @@ static inline int parameq(const char *input, const char *paramname)
49 85
50static int parse_one(char *param, 86static int parse_one(char *param,
51 char *val, 87 char *val,
52 struct kernel_param *params, 88 const struct kernel_param *params,
53 unsigned num_params, 89 unsigned num_params,
54 int (*handle_unknown)(char *param, char *val)) 90 int (*handle_unknown)(char *param, char *val))
55{ 91{
56 unsigned int i; 92 unsigned int i;
93 int err;
57 94
58 /* Find parameter */ 95 /* Find parameter */
59 for (i = 0; i < num_params; i++) { 96 for (i = 0; i < num_params; i++) {
60 if (parameq(param, params[i].name)) { 97 if (parameq(param, params[i].name)) {
98 /* Noone handled NULL, so do it here. */
99 if (!val && params[i].ops->set != param_set_bool)
100 return -EINVAL;
61 DEBUGP("They are equal! Calling %p\n", 101 DEBUGP("They are equal! Calling %p\n",
62 params[i].set); 102 params[i].ops->set);
63 return params[i].set(val, &params[i]); 103 mutex_lock(&param_lock);
104 err = params[i].ops->set(val, &params[i]);
105 mutex_unlock(&param_lock);
106 return err;
64 } 107 }
65 } 108 }
66 109
@@ -128,7 +171,7 @@ static char *next_arg(char *args, char **param, char **val)
128/* Args looks like "foo=bar,bar2 baz=fuz wiz". */ 171/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
129int parse_args(const char *name, 172int parse_args(const char *name,
130 char *args, 173 char *args,
131 struct kernel_param *params, 174 const struct kernel_param *params,
132 unsigned num, 175 unsigned num,
133 int (*unknown)(char *param, char *val)) 176 int (*unknown)(char *param, char *val))
134{ 177{
@@ -176,22 +219,29 @@ int parse_args(const char *name,
176 219
177/* Lazy bastard, eh? */ 220/* Lazy bastard, eh? */
178#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \ 221#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
179 int param_set_##name(const char *val, struct kernel_param *kp) \ 222 int param_set_##name(const char *val, const struct kernel_param *kp) \
180 { \ 223 { \
181 tmptype l; \ 224 tmptype l; \
182 int ret; \ 225 int ret; \
183 \ 226 \
184 if (!val) return -EINVAL; \
185 ret = strtolfn(val, 0, &l); \ 227 ret = strtolfn(val, 0, &l); \
186 if (ret == -EINVAL || ((type)l != l)) \ 228 if (ret == -EINVAL || ((type)l != l)) \
187 return -EINVAL; \ 229 return -EINVAL; \
188 *((type *)kp->arg) = l; \ 230 *((type *)kp->arg) = l; \
189 return 0; \ 231 return 0; \
190 } \ 232 } \
191 int param_get_##name(char *buffer, struct kernel_param *kp) \ 233 int param_get_##name(char *buffer, const struct kernel_param *kp) \
192 { \ 234 { \
193 return sprintf(buffer, format, *((type *)kp->arg)); \ 235 return sprintf(buffer, format, *((type *)kp->arg)); \
194 } 236 } \
237 struct kernel_param_ops param_ops_##name = { \
238 .set = param_set_##name, \
239 .get = param_get_##name, \
240 }; \
241 EXPORT_SYMBOL(param_set_##name); \
242 EXPORT_SYMBOL(param_get_##name); \
243 EXPORT_SYMBOL(param_ops_##name)
244
195 245
196STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul); 246STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
197STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol); 247STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
@@ -201,39 +251,50 @@ STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
201STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol); 251STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
202STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul); 252STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
203 253
204int param_set_charp(const char *val, struct kernel_param *kp) 254int param_set_charp(const char *val, const struct kernel_param *kp)
205{ 255{
206 if (!val) {
207 printk(KERN_ERR "%s: string parameter expected\n",
208 kp->name);
209 return -EINVAL;
210 }
211
212 if (strlen(val) > 1024) { 256 if (strlen(val) > 1024) {
213 printk(KERN_ERR "%s: string parameter too long\n", 257 printk(KERN_ERR "%s: string parameter too long\n",
214 kp->name); 258 kp->name);
215 return -ENOSPC; 259 return -ENOSPC;
216 } 260 }
217 261
218 /* This is a hack. We can't need to strdup in early boot, and we 262 maybe_kfree_parameter(*(char **)kp->arg);
263
264 /* This is a hack. We can't kmalloc in early boot, and we
219 * don't need to; this mangled commandline is preserved. */ 265 * don't need to; this mangled commandline is preserved. */
220 if (slab_is_available()) { 266 if (slab_is_available()) {
221 *(char **)kp->arg = kstrdup(val, GFP_KERNEL); 267 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
222 if (!*(char **)kp->arg) 268 if (!*(char **)kp->arg)
223 return -ENOMEM; 269 return -ENOMEM;
270 strcpy(*(char **)kp->arg, val);
224 } else 271 } else
225 *(const char **)kp->arg = val; 272 *(const char **)kp->arg = val;
226 273
227 return 0; 274 return 0;
228} 275}
276EXPORT_SYMBOL(param_set_charp);
229 277
230int param_get_charp(char *buffer, struct kernel_param *kp) 278int param_get_charp(char *buffer, const struct kernel_param *kp)
231{ 279{
232 return sprintf(buffer, "%s", *((char **)kp->arg)); 280 return sprintf(buffer, "%s", *((char **)kp->arg));
233} 281}
282EXPORT_SYMBOL(param_get_charp);
283
284static void param_free_charp(void *arg)
285{
286 maybe_kfree_parameter(*((char **)arg));
287}
288
289struct kernel_param_ops param_ops_charp = {
290 .set = param_set_charp,
291 .get = param_get_charp,
292 .free = param_free_charp,
293};
294EXPORT_SYMBOL(param_ops_charp);
234 295
235/* Actually could be a bool or an int, for historical reasons. */ 296/* Actually could be a bool or an int, for historical reasons. */
236int param_set_bool(const char *val, struct kernel_param *kp) 297int param_set_bool(const char *val, const struct kernel_param *kp)
237{ 298{
238 bool v; 299 bool v;
239 300
@@ -258,8 +319,9 @@ int param_set_bool(const char *val, struct kernel_param *kp)
258 *(int *)kp->arg = v; 319 *(int *)kp->arg = v;
259 return 0; 320 return 0;
260} 321}
322EXPORT_SYMBOL(param_set_bool);
261 323
262int param_get_bool(char *buffer, struct kernel_param *kp) 324int param_get_bool(char *buffer, const struct kernel_param *kp)
263{ 325{
264 bool val; 326 bool val;
265 if (kp->flags & KPARAM_ISBOOL) 327 if (kp->flags & KPARAM_ISBOOL)
@@ -270,9 +332,16 @@ int param_get_bool(char *buffer, struct kernel_param *kp)
270 /* Y and N chosen as being relatively non-coder friendly */ 332 /* Y and N chosen as being relatively non-coder friendly */
271 return sprintf(buffer, "%c", val ? 'Y' : 'N'); 333 return sprintf(buffer, "%c", val ? 'Y' : 'N');
272} 334}
335EXPORT_SYMBOL(param_get_bool);
336
337struct kernel_param_ops param_ops_bool = {
338 .set = param_set_bool,
339 .get = param_get_bool,
340};
341EXPORT_SYMBOL(param_ops_bool);
273 342
274/* This one must be bool. */ 343/* This one must be bool. */
275int param_set_invbool(const char *val, struct kernel_param *kp) 344int param_set_invbool(const char *val, const struct kernel_param *kp)
276{ 345{
277 int ret; 346 int ret;
278 bool boolval; 347 bool boolval;
@@ -285,18 +354,26 @@ int param_set_invbool(const char *val, struct kernel_param *kp)
285 *(bool *)kp->arg = !boolval; 354 *(bool *)kp->arg = !boolval;
286 return ret; 355 return ret;
287} 356}
357EXPORT_SYMBOL(param_set_invbool);
288 358
289int param_get_invbool(char *buffer, struct kernel_param *kp) 359int param_get_invbool(char *buffer, const struct kernel_param *kp)
290{ 360{
291 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y'); 361 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
292} 362}
363EXPORT_SYMBOL(param_get_invbool);
364
365struct kernel_param_ops param_ops_invbool = {
366 .set = param_set_invbool,
367 .get = param_get_invbool,
368};
369EXPORT_SYMBOL(param_ops_invbool);
293 370
294/* We break the rule and mangle the string. */ 371/* We break the rule and mangle the string. */
295static int param_array(const char *name, 372static int param_array(const char *name,
296 const char *val, 373 const char *val,
297 unsigned int min, unsigned int max, 374 unsigned int min, unsigned int max,
298 void *elem, int elemsize, 375 void *elem, int elemsize,
299 int (*set)(const char *, struct kernel_param *kp), 376 int (*set)(const char *, const struct kernel_param *kp),
300 u16 flags, 377 u16 flags,
301 unsigned int *num) 378 unsigned int *num)
302{ 379{
@@ -309,12 +386,6 @@ static int param_array(const char *name,
309 kp.arg = elem; 386 kp.arg = elem;
310 kp.flags = flags; 387 kp.flags = flags;
311 388
312 /* No equals sign? */
313 if (!val) {
314 printk(KERN_ERR "%s: expects arguments\n", name);
315 return -EINVAL;
316 }
317
318 *num = 0; 389 *num = 0;
319 /* We expect a comma-separated list of values. */ 390 /* We expect a comma-separated list of values. */
320 do { 391 do {
@@ -330,6 +401,7 @@ static int param_array(const char *name,
330 /* nul-terminate and parse */ 401 /* nul-terminate and parse */
331 save = val[len]; 402 save = val[len];
332 ((char *)val)[len] = '\0'; 403 ((char *)val)[len] = '\0';
404 BUG_ON(!mutex_is_locked(&param_lock));
333 ret = set(val, &kp); 405 ret = set(val, &kp);
334 406
335 if (ret != 0) 407 if (ret != 0)
@@ -347,17 +419,17 @@ static int param_array(const char *name,
347 return 0; 419 return 0;
348} 420}
349 421
350int param_array_set(const char *val, struct kernel_param *kp) 422static int param_array_set(const char *val, const struct kernel_param *kp)
351{ 423{
352 const struct kparam_array *arr = kp->arr; 424 const struct kparam_array *arr = kp->arr;
353 unsigned int temp_num; 425 unsigned int temp_num;
354 426
355 return param_array(kp->name, val, 1, arr->max, arr->elem, 427 return param_array(kp->name, val, 1, arr->max, arr->elem,
356 arr->elemsize, arr->set, kp->flags, 428 arr->elemsize, arr->ops->set, kp->flags,
357 arr->num ?: &temp_num); 429 arr->num ?: &temp_num);
358} 430}
359 431
360int param_array_get(char *buffer, struct kernel_param *kp) 432static int param_array_get(char *buffer, const struct kernel_param *kp)
361{ 433{
362 int i, off, ret; 434 int i, off, ret;
363 const struct kparam_array *arr = kp->arr; 435 const struct kparam_array *arr = kp->arr;
@@ -368,7 +440,8 @@ int param_array_get(char *buffer, struct kernel_param *kp)
368 if (i) 440 if (i)
369 buffer[off++] = ','; 441 buffer[off++] = ',';
370 p.arg = arr->elem + arr->elemsize * i; 442 p.arg = arr->elem + arr->elemsize * i;
371 ret = arr->get(buffer + off, &p); 443 BUG_ON(!mutex_is_locked(&param_lock));
444 ret = arr->ops->get(buffer + off, &p);
372 if (ret < 0) 445 if (ret < 0)
373 return ret; 446 return ret;
374 off += ret; 447 off += ret;
@@ -377,14 +450,27 @@ int param_array_get(char *buffer, struct kernel_param *kp)
377 return off; 450 return off;
378} 451}
379 452
380int param_set_copystring(const char *val, struct kernel_param *kp) 453static void param_array_free(void *arg)
454{
455 unsigned int i;
456 const struct kparam_array *arr = arg;
457
458 if (arr->ops->free)
459 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
460 arr->ops->free(arr->elem + arr->elemsize * i);
461}
462
463struct kernel_param_ops param_array_ops = {
464 .set = param_array_set,
465 .get = param_array_get,
466 .free = param_array_free,
467};
468EXPORT_SYMBOL(param_array_ops);
469
470int param_set_copystring(const char *val, const struct kernel_param *kp)
381{ 471{
382 const struct kparam_string *kps = kp->str; 472 const struct kparam_string *kps = kp->str;
383 473
384 if (!val) {
385 printk(KERN_ERR "%s: missing param set value\n", kp->name);
386 return -EINVAL;
387 }
388 if (strlen(val)+1 > kps->maxlen) { 474 if (strlen(val)+1 > kps->maxlen) {
389 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n", 475 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
390 kp->name, kps->maxlen-1); 476 kp->name, kps->maxlen-1);
@@ -393,12 +479,20 @@ int param_set_copystring(const char *val, struct kernel_param *kp)
393 strcpy(kps->string, val); 479 strcpy(kps->string, val);
394 return 0; 480 return 0;
395} 481}
482EXPORT_SYMBOL(param_set_copystring);
396 483
397int param_get_string(char *buffer, struct kernel_param *kp) 484int param_get_string(char *buffer, const struct kernel_param *kp)
398{ 485{
399 const struct kparam_string *kps = kp->str; 486 const struct kparam_string *kps = kp->str;
400 return strlcpy(buffer, kps->string, kps->maxlen); 487 return strlcpy(buffer, kps->string, kps->maxlen);
401} 488}
489EXPORT_SYMBOL(param_get_string);
490
491struct kernel_param_ops param_ops_string = {
492 .set = param_set_copystring,
493 .get = param_get_string,
494};
495EXPORT_SYMBOL(param_ops_string);
402 496
403/* sysfs output in /sys/modules/XYZ/parameters/ */ 497/* sysfs output in /sys/modules/XYZ/parameters/ */
404#define to_module_attr(n) container_of(n, struct module_attribute, attr) 498#define to_module_attr(n) container_of(n, struct module_attribute, attr)
@@ -409,7 +503,7 @@ extern struct kernel_param __start___param[], __stop___param[];
409struct param_attribute 503struct param_attribute
410{ 504{
411 struct module_attribute mattr; 505 struct module_attribute mattr;
412 struct kernel_param *param; 506 const struct kernel_param *param;
413}; 507};
414 508
415struct module_param_attrs 509struct module_param_attrs
@@ -428,10 +522,12 @@ static ssize_t param_attr_show(struct module_attribute *mattr,
428 int count; 522 int count;
429 struct param_attribute *attribute = to_param_attr(mattr); 523 struct param_attribute *attribute = to_param_attr(mattr);
430 524
431 if (!attribute->param->get) 525 if (!attribute->param->ops->get)
432 return -EPERM; 526 return -EPERM;
433 527
434 count = attribute->param->get(buf, attribute->param); 528 mutex_lock(&param_lock);
529 count = attribute->param->ops->get(buf, attribute->param);
530 mutex_unlock(&param_lock);
435 if (count > 0) { 531 if (count > 0) {
436 strcat(buf, "\n"); 532 strcat(buf, "\n");
437 ++count; 533 ++count;
@@ -447,10 +543,12 @@ static ssize_t param_attr_store(struct module_attribute *mattr,
447 int err; 543 int err;
448 struct param_attribute *attribute = to_param_attr(mattr); 544 struct param_attribute *attribute = to_param_attr(mattr);
449 545
450 if (!attribute->param->set) 546 if (!attribute->param->ops->set)
451 return -EPERM; 547 return -EPERM;
452 548
453 err = attribute->param->set(buf, attribute->param); 549 mutex_lock(&param_lock);
550 err = attribute->param->ops->set(buf, attribute->param);
551 mutex_unlock(&param_lock);
454 if (!err) 552 if (!err)
455 return len; 553 return len;
456 return err; 554 return err;
@@ -464,6 +562,18 @@ static ssize_t param_attr_store(struct module_attribute *mattr,
464#endif 562#endif
465 563
466#ifdef CONFIG_SYSFS 564#ifdef CONFIG_SYSFS
565void __kernel_param_lock(void)
566{
567 mutex_lock(&param_lock);
568}
569EXPORT_SYMBOL(__kernel_param_lock);
570
571void __kernel_param_unlock(void)
572{
573 mutex_unlock(&param_lock);
574}
575EXPORT_SYMBOL(__kernel_param_unlock);
576
467/* 577/*
468 * add_sysfs_param - add a parameter to sysfs 578 * add_sysfs_param - add a parameter to sysfs
469 * @mk: struct module_kobject 579 * @mk: struct module_kobject
@@ -475,7 +585,7 @@ static ssize_t param_attr_store(struct module_attribute *mattr,
475 * if there's an error. 585 * if there's an error.
476 */ 586 */
477static __modinit int add_sysfs_param(struct module_kobject *mk, 587static __modinit int add_sysfs_param(struct module_kobject *mk,
478 struct kernel_param *kp, 588 const struct kernel_param *kp,
479 const char *name) 589 const char *name)
480{ 590{
481 struct module_param_attrs *new; 591 struct module_param_attrs *new;
@@ -557,7 +667,7 @@ static void free_module_param_attrs(struct module_kobject *mk)
557 * /sys/module/[mod->name]/parameters/ 667 * /sys/module/[mod->name]/parameters/
558 */ 668 */
559int module_param_sysfs_setup(struct module *mod, 669int module_param_sysfs_setup(struct module *mod,
560 struct kernel_param *kparam, 670 const struct kernel_param *kparam,
561 unsigned int num_params) 671 unsigned int num_params)
562{ 672{
563 int i, err; 673 int i, err;
@@ -602,7 +712,11 @@ void module_param_sysfs_remove(struct module *mod)
602 712
603void destroy_params(const struct kernel_param *params, unsigned num) 713void destroy_params(const struct kernel_param *params, unsigned num)
604{ 714{
605 /* FIXME: This should free kmalloced charp parameters. It doesn't. */ 715 unsigned int i;
716
717 for (i = 0; i < num; i++)
718 if (params[i].ops->free)
719 params[i].ops->free(params[i].arg);
606} 720}
607 721
608static void __init kernel_add_sysfs_param(const char *name, 722static void __init kernel_add_sysfs_param(const char *name,
@@ -768,28 +882,3 @@ static int __init param_sysfs_init(void)
768subsys_initcall(param_sysfs_init); 882subsys_initcall(param_sysfs_init);
769 883
770#endif /* CONFIG_SYSFS */ 884#endif /* CONFIG_SYSFS */
771
772EXPORT_SYMBOL(param_set_byte);
773EXPORT_SYMBOL(param_get_byte);
774EXPORT_SYMBOL(param_set_short);
775EXPORT_SYMBOL(param_get_short);
776EXPORT_SYMBOL(param_set_ushort);
777EXPORT_SYMBOL(param_get_ushort);
778EXPORT_SYMBOL(param_set_int);
779EXPORT_SYMBOL(param_get_int);
780EXPORT_SYMBOL(param_set_uint);
781EXPORT_SYMBOL(param_get_uint);
782EXPORT_SYMBOL(param_set_long);
783EXPORT_SYMBOL(param_get_long);
784EXPORT_SYMBOL(param_set_ulong);
785EXPORT_SYMBOL(param_get_ulong);
786EXPORT_SYMBOL(param_set_charp);
787EXPORT_SYMBOL(param_get_charp);
788EXPORT_SYMBOL(param_set_bool);
789EXPORT_SYMBOL(param_get_bool);
790EXPORT_SYMBOL(param_set_invbool);
791EXPORT_SYMBOL(param_get_invbool);
792EXPORT_SYMBOL(param_array_set);
793EXPORT_SYMBOL(param_array_get);
794EXPORT_SYMBOL(param_set_copystring);
795EXPORT_SYMBOL(param_get_string);
generated by cgit v1.2.2 (git 2.25.0) at 2025-11-01 15:08:05 -0400