1 /* Helpers for initial module or kernel cmdline parsing
2 Copyright (C) 2001 Rusty Russell.
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.
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.
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
18 #include <linux/config.h>
19 #include <linux/moduleparam.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/errno.h>
23 #include <linux/module.h>
24 #include <linux/device.h>
25 #include <linux/err.h>
30 #define DEBUGP(fmt, a...)
33 static inline int dash2underscore(char c)
40 static inline int parameq(const char *input, const char *paramname)
43 for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
49 static int parse_one(char *param,
51 struct kernel_param *params,
53 int (*handle_unknown)(char *param, char *val))
58 for (i = 0; i < num_params; i++) {
59 if (parameq(param, params[i].name)) {
60 DEBUGP("They are equal! Calling %p\n",
62 return params[i].set(val, ¶ms[i]);
67 DEBUGP("Unknown argument: calling %p\n", handle_unknown);
68 return handle_unknown(param, val);
71 DEBUGP("Unknown argument `%s'\n", param);
75 /* You can use " around spaces, but can't escape ". */
76 /* Hyphens and underscores equivalent in parameter names. */
77 static char *next_arg(char *args, char **param, char **val)
79 unsigned int i, equals = 0;
80 int in_quote = 0, quoted = 0;
89 for (i = 0; args[i]; i++) {
90 if (args[i] == ' ' && !in_quote)
105 *val = args + equals + 1;
107 /* Don't include quotes in value. */
110 if (args[i-1] == '"')
113 if (quoted && args[i-1] == '"')
123 /* Chew up trailing spaces. */
129 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
130 int parse_args(const char *name,
132 struct kernel_param *params,
134 int (*unknown)(char *param, char *val))
138 DEBUGP("Parsing ARGS: %s\n", args);
140 /* Chew leading spaces */
147 args = next_arg(args, ¶m, &val);
148 ret = parse_one(param, val, params, num, unknown);
151 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
156 "%s: `%s' too large for parameter `%s'\n",
157 name, val ?: "", param);
163 "%s: `%s' invalid for parameter `%s'\n",
164 name, val ?: "", param);
173 /* Lazy bastard, eh? */
174 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
175 int param_set_##name(const char *val, struct kernel_param *kp) \
180 if (!val) return -EINVAL; \
181 l = strtolfn(val, &endp, 0); \
182 if (endp == val || ((type)l != l)) \
184 *((type *)kp->arg) = l; \
187 int param_get_##name(char *buffer, struct kernel_param *kp) \
189 return sprintf(buffer, format, *((type *)kp->arg)); \
192 STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, simple_strtoul);
193 STANDARD_PARAM_DEF(short, short, "%hi", long, simple_strtol);
194 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, simple_strtoul);
195 STANDARD_PARAM_DEF(int, int, "%i", long, simple_strtol);
196 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, simple_strtoul);
197 STANDARD_PARAM_DEF(long, long, "%li", long, simple_strtol);
198 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, simple_strtoul);
200 int param_set_charp(const char *val, struct kernel_param *kp)
203 printk(KERN_ERR "%s: string parameter expected\n",
208 if (strlen(val) > 1024) {
209 printk(KERN_ERR "%s: string parameter too long\n",
214 *(char **)kp->arg = (char *)val;
218 int param_get_charp(char *buffer, struct kernel_param *kp)
220 return sprintf(buffer, "%s", *((char **)kp->arg));
223 int param_set_bool(const char *val, struct kernel_param *kp)
225 /* No equals means "set"... */
228 /* One of =[yYnN01] */
230 case 'y': case 'Y': case '1':
233 case 'n': case 'N': case '0':
240 int param_get_bool(char *buffer, struct kernel_param *kp)
242 /* Y and N chosen as being relatively non-coder friendly */
243 return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'Y' : 'N');
246 int param_set_invbool(const char *val, struct kernel_param *kp)
249 struct kernel_param dummy = { .arg = &boolval };
251 ret = param_set_bool(val, &dummy);
253 *(int *)kp->arg = !boolval;
257 int param_get_invbool(char *buffer, struct kernel_param *kp)
260 struct kernel_param dummy = { .arg = &val };
262 val = !*(int *)kp->arg;
263 return param_get_bool(buffer, &dummy);
266 /* We cheat here and temporarily mangle the string. */
267 int param_array(const char *name,
269 unsigned int min, unsigned int max,
270 void *elem, int elemsize,
271 int (*set)(const char *, struct kernel_param *kp),
275 struct kernel_param kp;
278 /* Get the name right for errors. */
282 /* No equals sign? */
284 printk(KERN_ERR "%s: expects arguments\n", name);
289 /* We expect a comma-separated list of values. */
294 printk(KERN_ERR "%s: can only take %i arguments\n",
298 len = strcspn(val, ",");
300 /* nul-terminate and parse */
302 ((char *)val)[len] = '\0';
310 } while (save == ',');
313 printk(KERN_ERR "%s: needs at least %i arguments\n",
320 int param_array_set(const char *val, struct kernel_param *kp)
322 struct kparam_array *arr = kp->arg;
323 unsigned int temp_num;
325 return param_array(kp->name, val, 1, arr->max, arr->elem,
326 arr->elemsize, arr->set, arr->num ?: &temp_num);
329 int param_array_get(char *buffer, struct kernel_param *kp)
332 struct kparam_array *arr = kp->arg;
333 struct kernel_param p;
336 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
339 p.arg = arr->elem + arr->elemsize * i;
340 ret = arr->get(buffer + off, &p);
349 int param_set_copystring(const char *val, struct kernel_param *kp)
351 struct kparam_string *kps = kp->arg;
353 if (strlen(val)+1 > kps->maxlen) {
354 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
355 kp->name, kps->maxlen-1);
358 strcpy(kps->string, val);
362 int param_get_string(char *buffer, struct kernel_param *kp)
364 struct kparam_string *kps = kp->arg;
365 return strlcpy(buffer, kps->string, kps->maxlen);
368 /* sysfs output in /sys/modules/XYZ/parameters/ */
370 extern struct kernel_param __start___param[], __stop___param[];
372 #define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
374 struct param_attribute
376 struct module_attribute mattr;
377 struct kernel_param *param;
380 struct module_param_attrs
382 struct attribute_group grp;
383 struct param_attribute attrs[0];
386 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
388 static ssize_t param_attr_show(struct module_attribute *mattr,
389 struct module *mod, char *buf)
392 struct param_attribute *attribute = to_param_attr(mattr);
394 if (!attribute->param->get)
397 count = attribute->param->get(buf, attribute->param);
405 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
406 static ssize_t param_attr_store(struct module_attribute *mattr,
407 struct module *owner,
408 const char *buf, size_t len)
411 struct param_attribute *attribute = to_param_attr(mattr);
413 if (!attribute->param->set)
416 err = attribute->param->set(buf, attribute->param);
422 #ifdef CONFIG_MODULES
425 #define __modinit __init
429 * param_sysfs_setup - setup sysfs support for one module or KBUILD_MODNAME
430 * @mk: struct module_kobject (contains parent kobject)
431 * @kparam: array of struct kernel_param, the actual parameter definitions
432 * @num_params: number of entries in array
433 * @name_skip: offset where the parameter name start in kparam[].name. Needed for built-in "modules"
435 * Create a kobject for a (per-module) group of parameters, and create files
436 * in sysfs. A pointer to the param_kobject is returned on success,
437 * NULL if there's no parameter to export, or other ERR_PTR(err).
439 static __modinit struct module_param_attrs *
440 param_sysfs_setup(struct module_kobject *mk,
441 struct kernel_param *kparam,
442 unsigned int num_params,
443 unsigned int name_skip)
445 struct module_param_attrs *mp;
446 unsigned int valid_attrs = 0;
447 unsigned int i, size[2];
448 struct param_attribute *pattr;
449 struct attribute **gattr;
452 for (i=0; i<num_params; i++) {
460 size[0] = ALIGN(sizeof(*mp) +
461 valid_attrs * sizeof(mp->attrs[0]),
462 sizeof(mp->grp.attrs[0]));
463 size[1] = (valid_attrs + 1) * sizeof(mp->grp.attrs[0]);
465 mp = kmalloc(size[0] + size[1], GFP_KERNEL);
467 return ERR_PTR(-ENOMEM);
469 mp->grp.name = "parameters";
470 mp->grp.attrs = (void *)mp + size[0];
472 pattr = &mp->attrs[0];
473 gattr = &mp->grp.attrs[0];
474 for (i = 0; i < num_params; i++) {
475 struct kernel_param *kp = &kparam[i];
478 pattr->mattr.show = param_attr_show;
479 pattr->mattr.store = param_attr_store;
480 pattr->mattr.attr.name = (char *)&kp->name[name_skip];
481 pattr->mattr.attr.owner = mk->mod;
482 pattr->mattr.attr.mode = kp->perm;
483 *(gattr++) = &(pattr++)->mattr.attr;
488 if ((err = sysfs_create_group(&mk->kobj, &mp->grp))) {
496 #ifdef CONFIG_MODULES
499 * module_param_sysfs_setup - setup sysfs support for one module
501 * @kparam: module parameters (array)
502 * @num_params: number of module parameters
504 * Adds sysfs entries for module parameters, and creates a link from
505 * /sys/module/[mod->name]/parameters to /sys/parameters/[mod->name]/
507 int module_param_sysfs_setup(struct module *mod,
508 struct kernel_param *kparam,
509 unsigned int num_params)
511 struct module_param_attrs *mp;
513 mp = param_sysfs_setup(&mod->mkobj, kparam, num_params, 0);
517 mod->param_attrs = mp;
522 * module_param_sysfs_remove - remove sysfs support for one module
525 * Remove sysfs entries for module parameters and the corresponding
528 void module_param_sysfs_remove(struct module *mod)
530 if (mod->param_attrs) {
531 sysfs_remove_group(&mod->mkobj.kobj,
532 &mod->param_attrs->grp);
533 /* We are positive that no one is using any param
534 * attrs at this point. Deallocate immediately. */
535 kfree(mod->param_attrs);
536 mod->param_attrs = NULL;
542 * kernel_param_sysfs_setup - wrapper for built-in params support
544 static void __init kernel_param_sysfs_setup(const char *name,
545 struct kernel_param *kparam,
546 unsigned int num_params,
547 unsigned int name_skip)
549 struct module_kobject *mk;
551 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
554 mk->mod = THIS_MODULE;
555 kobj_set_kset_s(mk, module_subsys);
556 kobject_set_name(&mk->kobj, name);
557 kobject_register(&mk->kobj);
559 /* no need to keep the kobject if no parameter is exported */
560 if (!param_sysfs_setup(mk, kparam, num_params, name_skip)) {
561 kobject_unregister(&mk->kobj);
567 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
569 * Add module_parameters to sysfs for "modules" built into the kernel.
571 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
572 * "parameter" name is stored behind a dot in kernel_param->name. So,
573 * extract the "module" name for all built-in kernel_param-eters,
574 * and for all who have the same, call kernel_param_sysfs_setup.
576 static void __init param_sysfs_builtin(void)
578 struct kernel_param *kp, *kp_begin = NULL;
579 unsigned int i, name_len, count = 0;
580 char modname[MAX_KBUILD_MODNAME + 1] = "";
582 for (i=0; i < __stop___param - __start___param; i++) {
585 kp = &__start___param[i];
587 /* We do not handle args without periods. */
588 dot = memchr(kp->name, '.', MAX_KBUILD_MODNAME);
590 DEBUGP("couldn't find period in %s\n", kp->name);
593 name_len = dot - kp->name;
595 /* new kbuild_modname? */
596 if (strlen(modname) != name_len
597 || strncmp(modname, kp->name, name_len) != 0) {
598 /* add a new kobject for previous kernel_params. */
600 kernel_param_sysfs_setup(modname,
605 strncpy(modname, kp->name, name_len);
606 modname[name_len] = '\0';
613 /* last kernel_params need to be registered as well */
615 kernel_param_sysfs_setup(modname, kp_begin, count,
620 /* module-related sysfs stuff */
621 #ifdef CONFIG_MODULES
623 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
624 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
626 static ssize_t module_attr_show(struct kobject *kobj,
627 struct attribute *attr,
630 struct module_attribute *attribute;
631 struct module_kobject *mk;
634 attribute = to_module_attr(attr);
635 mk = to_module_kobject(kobj);
637 if (!attribute->show)
640 if (!try_module_get(mk->mod))
643 ret = attribute->show(attribute, mk->mod, buf);
650 static ssize_t module_attr_store(struct kobject *kobj,
651 struct attribute *attr,
652 const char *buf, size_t len)
654 struct module_attribute *attribute;
655 struct module_kobject *mk;
658 attribute = to_module_attr(attr);
659 mk = to_module_kobject(kobj);
661 if (!attribute->store)
664 if (!try_module_get(mk->mod))
667 ret = attribute->store(attribute, mk->mod, buf, len);
674 static struct sysfs_ops module_sysfs_ops = {
675 .show = module_attr_show,
676 .store = module_attr_store,
680 static struct sysfs_ops module_sysfs_ops = {
686 static struct kobj_type module_ktype = {
687 .sysfs_ops = &module_sysfs_ops,
690 decl_subsys(module, &module_ktype, NULL);
693 * param_sysfs_init - wrapper for built-in params support
695 static int __init param_sysfs_init(void)
697 subsystem_register(&module_subsys);
699 param_sysfs_builtin();
703 __initcall(param_sysfs_init);
705 EXPORT_SYMBOL(param_set_byte);
706 EXPORT_SYMBOL(param_get_byte);
707 EXPORT_SYMBOL(param_set_short);
708 EXPORT_SYMBOL(param_get_short);
709 EXPORT_SYMBOL(param_set_ushort);
710 EXPORT_SYMBOL(param_get_ushort);
711 EXPORT_SYMBOL(param_set_int);
712 EXPORT_SYMBOL(param_get_int);
713 EXPORT_SYMBOL(param_set_uint);
714 EXPORT_SYMBOL(param_get_uint);
715 EXPORT_SYMBOL(param_set_long);
716 EXPORT_SYMBOL(param_get_long);
717 EXPORT_SYMBOL(param_set_ulong);
718 EXPORT_SYMBOL(param_get_ulong);
719 EXPORT_SYMBOL(param_set_charp);
720 EXPORT_SYMBOL(param_get_charp);
721 EXPORT_SYMBOL(param_set_bool);
722 EXPORT_SYMBOL(param_get_bool);
723 EXPORT_SYMBOL(param_set_invbool);
724 EXPORT_SYMBOL(param_get_invbool);
725 EXPORT_SYMBOL(param_array_set);
726 EXPORT_SYMBOL(param_array_get);
727 EXPORT_SYMBOL(param_set_copystring);
728 EXPORT_SYMBOL(param_get_string);