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/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>
25 #include <linux/slab.h>
26 #include <linux/ctype.h>
31 #define DEBUGP(fmt, a...)
34 static inline char dash2underscore(char c)
41 static inline int parameq(const char *input, const char *paramname)
44 for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
50 static int parse_one(char *param,
52 struct kernel_param *params,
54 int (*handle_unknown)(char *param, char *val))
59 for (i = 0; i < num_params; i++) {
60 if (parameq(param, params[i].name)) {
61 /* Noone handled NULL, so do it here. */
62 if (!val && params[i].ops->set != param_set_bool)
64 DEBUGP("They are equal! Calling %p\n",
66 return params[i].ops->set(val, ¶ms[i]);
71 DEBUGP("Unknown argument: calling %p\n", handle_unknown);
72 return handle_unknown(param, val);
75 DEBUGP("Unknown argument `%s'\n", param);
79 /* You can use " around spaces, but can't escape ". */
80 /* Hyphens and underscores equivalent in parameter names. */
81 static char *next_arg(char *args, char **param, char **val)
83 unsigned int i, equals = 0;
84 int in_quote = 0, quoted = 0;
93 for (i = 0; args[i]; i++) {
94 if (isspace(args[i]) && !in_quote)
101 in_quote = !in_quote;
109 *val = args + equals + 1;
111 /* Don't include quotes in value. */
114 if (args[i-1] == '"')
117 if (quoted && args[i-1] == '"')
127 /* Chew up trailing spaces. */
128 return skip_spaces(next);
131 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
132 int parse_args(const char *name,
134 struct kernel_param *params,
136 int (*unknown)(char *param, char *val))
140 DEBUGP("Parsing ARGS: %s\n", args);
142 /* Chew leading spaces */
143 args = skip_spaces(args);
147 int irq_was_disabled;
149 args = next_arg(args, ¶m, &val);
150 irq_was_disabled = irqs_disabled();
151 ret = parse_one(param, val, params, num, unknown);
152 if (irq_was_disabled && !irqs_disabled()) {
153 printk(KERN_WARNING "parse_args(): option '%s' enabled "
158 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
163 "%s: `%s' too large for parameter `%s'\n",
164 name, val ?: "", param);
170 "%s: `%s' invalid for parameter `%s'\n",
171 name, val ?: "", param);
180 /* Lazy bastard, eh? */
181 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
182 int param_set_##name(const char *val, const struct kernel_param *kp) \
187 ret = strtolfn(val, 0, &l); \
188 if (ret == -EINVAL || ((type)l != l)) \
190 *((type *)kp->arg) = l; \
193 int param_get_##name(char *buffer, const struct kernel_param *kp) \
195 return sprintf(buffer, format, *((type *)kp->arg)); \
197 struct kernel_param_ops param_ops_##name = { \
198 .set = param_set_##name, \
199 .get = param_get_##name, \
201 EXPORT_SYMBOL(param_set_##name); \
202 EXPORT_SYMBOL(param_get_##name); \
203 EXPORT_SYMBOL(param_ops_##name)
206 STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
207 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
208 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
209 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
210 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
211 STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
212 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
214 int param_set_charp(const char *val, const struct kernel_param *kp)
216 if (strlen(val) > 1024) {
217 printk(KERN_ERR "%s: string parameter too long\n",
222 /* This is a hack. We can't need to strdup in early boot, and we
223 * don't need to; this mangled commandline is preserved. */
224 if (slab_is_available()) {
225 *(char **)kp->arg = kstrdup(val, GFP_KERNEL);
226 if (!*(char **)kp->arg)
229 *(const char **)kp->arg = val;
233 EXPORT_SYMBOL(param_set_charp);
235 int param_get_charp(char *buffer, const struct kernel_param *kp)
237 return sprintf(buffer, "%s", *((char **)kp->arg));
239 EXPORT_SYMBOL(param_get_charp);
241 struct kernel_param_ops param_ops_charp = {
242 .set = param_set_charp,
243 .get = param_get_charp,
245 EXPORT_SYMBOL(param_ops_charp);
247 /* Actually could be a bool or an int, for historical reasons. */
248 int param_set_bool(const char *val, const struct kernel_param *kp)
252 /* No equals means "set"... */
255 /* One of =[yYnN01] */
257 case 'y': case 'Y': case '1':
260 case 'n': case 'N': case '0':
267 if (kp->flags & KPARAM_ISBOOL)
268 *(bool *)kp->arg = v;
273 EXPORT_SYMBOL(param_set_bool);
275 int param_get_bool(char *buffer, const struct kernel_param *kp)
278 if (kp->flags & KPARAM_ISBOOL)
279 val = *(bool *)kp->arg;
281 val = *(int *)kp->arg;
283 /* Y and N chosen as being relatively non-coder friendly */
284 return sprintf(buffer, "%c", val ? 'Y' : 'N');
286 EXPORT_SYMBOL(param_get_bool);
288 struct kernel_param_ops param_ops_bool = {
289 .set = param_set_bool,
290 .get = param_get_bool,
292 EXPORT_SYMBOL(param_ops_bool);
294 /* This one must be bool. */
295 int param_set_invbool(const char *val, const struct kernel_param *kp)
299 struct kernel_param dummy;
301 dummy.arg = &boolval;
302 dummy.flags = KPARAM_ISBOOL;
303 ret = param_set_bool(val, &dummy);
305 *(bool *)kp->arg = !boolval;
308 EXPORT_SYMBOL(param_set_invbool);
310 int param_get_invbool(char *buffer, const struct kernel_param *kp)
312 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
314 EXPORT_SYMBOL(param_get_invbool);
316 struct kernel_param_ops param_ops_invbool = {
317 .set = param_set_invbool,
318 .get = param_get_invbool,
320 EXPORT_SYMBOL(param_ops_invbool);
322 /* We break the rule and mangle the string. */
323 static int param_array(const char *name,
325 unsigned int min, unsigned int max,
326 void *elem, int elemsize,
327 int (*set)(const char *, const struct kernel_param *kp),
332 struct kernel_param kp;
335 /* Get the name right for errors. */
341 /* We expect a comma-separated list of values. */
346 printk(KERN_ERR "%s: can only take %i arguments\n",
350 len = strcspn(val, ",");
352 /* nul-terminate and parse */
354 ((char *)val)[len] = '\0';
362 } while (save == ',');
365 printk(KERN_ERR "%s: needs at least %i arguments\n",
372 static int param_array_set(const char *val, const struct kernel_param *kp)
374 const struct kparam_array *arr = kp->arr;
375 unsigned int temp_num;
377 return param_array(kp->name, val, 1, arr->max, arr->elem,
378 arr->elemsize, arr->ops->set, kp->flags,
379 arr->num ?: &temp_num);
382 static int param_array_get(char *buffer, const struct kernel_param *kp)
385 const struct kparam_array *arr = kp->arr;
386 struct kernel_param p;
389 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
392 p.arg = arr->elem + arr->elemsize * i;
393 ret = arr->ops->get(buffer + off, &p);
402 static void param_array_free(void *arg)
405 const struct kparam_array *arr = arg;
408 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
409 arr->ops->free(arr->elem + arr->elemsize * i);
412 struct kernel_param_ops param_array_ops = {
413 .set = param_array_set,
414 .get = param_array_get,
415 .free = param_array_free,
417 EXPORT_SYMBOL(param_array_ops);
419 int param_set_copystring(const char *val, const struct kernel_param *kp)
421 const struct kparam_string *kps = kp->str;
423 if (strlen(val)+1 > kps->maxlen) {
424 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
425 kp->name, kps->maxlen-1);
428 strcpy(kps->string, val);
431 EXPORT_SYMBOL(param_set_copystring);
433 int param_get_string(char *buffer, const struct kernel_param *kp)
435 const struct kparam_string *kps = kp->str;
436 return strlcpy(buffer, kps->string, kps->maxlen);
438 EXPORT_SYMBOL(param_get_string);
440 struct kernel_param_ops param_ops_string = {
441 .set = param_set_copystring,
442 .get = param_get_string,
444 EXPORT_SYMBOL(param_ops_string);
446 /* sysfs output in /sys/modules/XYZ/parameters/ */
447 #define to_module_attr(n) container_of(n, struct module_attribute, attr)
448 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
450 extern struct kernel_param __start___param[], __stop___param[];
452 struct param_attribute
454 struct module_attribute mattr;
455 const struct kernel_param *param;
458 struct module_param_attrs
461 struct attribute_group grp;
462 struct param_attribute attrs[0];
466 #define to_param_attr(n) container_of(n, struct param_attribute, mattr)
468 static ssize_t param_attr_show(struct module_attribute *mattr,
469 struct module *mod, char *buf)
472 struct param_attribute *attribute = to_param_attr(mattr);
474 if (!attribute->param->ops->get)
477 count = attribute->param->ops->get(buf, attribute->param);
485 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
486 static ssize_t param_attr_store(struct module_attribute *mattr,
487 struct module *owner,
488 const char *buf, size_t len)
491 struct param_attribute *attribute = to_param_attr(mattr);
493 if (!attribute->param->ops->set)
496 err = attribute->param->ops->set(buf, attribute->param);
503 #ifdef CONFIG_MODULES
506 #define __modinit __init
511 * add_sysfs_param - add a parameter to sysfs
512 * @mk: struct module_kobject
513 * @kparam: the actual parameter definition to add to sysfs
514 * @name: name of parameter
516 * Create a kobject if for a (per-module) parameter if mp NULL, and
517 * create file in sysfs. Returns an error on out of memory. Always cleans up
518 * if there's an error.
520 static __modinit int add_sysfs_param(struct module_kobject *mk,
521 const struct kernel_param *kp,
524 struct module_param_attrs *new;
525 struct attribute **attrs;
528 /* We don't bother calling this with invisible parameters. */
536 attrs = mk->mp->grp.attrs;
540 new = krealloc(mk->mp,
541 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
548 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
554 /* Sysfs wants everything zeroed. */
555 memset(new, 0, sizeof(*new));
556 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
557 memset(&attrs[num], 0, sizeof(attrs[num]));
558 new->grp.name = "parameters";
559 new->grp.attrs = attrs;
561 /* Tack new one on the end. */
562 sysfs_attr_init(&new->attrs[num].mattr.attr);
563 new->attrs[num].param = kp;
564 new->attrs[num].mattr.show = param_attr_show;
565 new->attrs[num].mattr.store = param_attr_store;
566 new->attrs[num].mattr.attr.name = (char *)name;
567 new->attrs[num].mattr.attr.mode = kp->perm;
570 /* Fix up all the pointers, since krealloc can move us */
571 for (num = 0; num < new->num; num++)
572 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
573 new->grp.attrs[num] = NULL;
585 #ifdef CONFIG_MODULES
586 static void free_module_param_attrs(struct module_kobject *mk)
588 kfree(mk->mp->grp.attrs);
594 * module_param_sysfs_setup - setup sysfs support for one module
596 * @kparam: module parameters (array)
597 * @num_params: number of module parameters
599 * Adds sysfs entries for module parameters under
600 * /sys/module/[mod->name]/parameters/
602 int module_param_sysfs_setup(struct module *mod,
603 const struct kernel_param *kparam,
604 unsigned int num_params)
609 for (i = 0; i < num_params; i++) {
610 if (kparam[i].perm == 0)
612 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
621 /* Create the param group. */
622 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
624 free_module_param_attrs(&mod->mkobj);
629 * module_param_sysfs_remove - remove sysfs support for one module
632 * Remove sysfs entries for module parameters and the corresponding
635 void module_param_sysfs_remove(struct module *mod)
638 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
639 /* We are positive that no one is using any param
640 * attrs at this point. Deallocate immediately. */
641 free_module_param_attrs(&mod->mkobj);
646 void destroy_params(const struct kernel_param *params, unsigned num)
650 for (i = 0; i < num; i++)
651 if (params[i].ops->free)
652 params[i].ops->free(params[i].arg);
655 static void __init kernel_add_sysfs_param(const char *name,
656 struct kernel_param *kparam,
657 unsigned int name_skip)
659 struct module_kobject *mk;
660 struct kobject *kobj;
663 kobj = kset_find_obj(module_kset, name);
665 /* We already have one. Remove params so we can add more. */
666 mk = to_module_kobject(kobj);
667 /* We need to remove it before adding parameters. */
668 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
670 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
673 mk->mod = THIS_MODULE;
674 mk->kobj.kset = module_kset;
675 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
678 kobject_put(&mk->kobj);
679 printk(KERN_ERR "Module '%s' failed add to sysfs, "
680 "error number %d\n", name, err);
681 printk(KERN_ERR "The system will be unstable now.\n");
684 /* So that exit path is even. */
685 kobject_get(&mk->kobj);
688 /* These should not fail at boot. */
689 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
691 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
693 kobject_uevent(&mk->kobj, KOBJ_ADD);
694 kobject_put(&mk->kobj);
698 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
700 * Add module_parameters to sysfs for "modules" built into the kernel.
702 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
703 * "parameter" name is stored behind a dot in kernel_param->name. So,
704 * extract the "module" name for all built-in kernel_param-eters,
705 * and for all who have the same, call kernel_add_sysfs_param.
707 static void __init param_sysfs_builtin(void)
709 struct kernel_param *kp;
710 unsigned int name_len;
711 char modname[MODULE_NAME_LEN];
713 for (kp = __start___param; kp < __stop___param; kp++) {
719 dot = strchr(kp->name, '.');
721 /* This happens for core_param() */
722 strcpy(modname, "kernel");
725 name_len = dot - kp->name + 1;
726 strlcpy(modname, kp->name, name_len);
728 kernel_add_sysfs_param(modname, kp, name_len);
733 /* module-related sysfs stuff */
735 static ssize_t module_attr_show(struct kobject *kobj,
736 struct attribute *attr,
739 struct module_attribute *attribute;
740 struct module_kobject *mk;
743 attribute = to_module_attr(attr);
744 mk = to_module_kobject(kobj);
746 if (!attribute->show)
749 ret = attribute->show(attribute, mk->mod, buf);
754 static ssize_t module_attr_store(struct kobject *kobj,
755 struct attribute *attr,
756 const char *buf, size_t len)
758 struct module_attribute *attribute;
759 struct module_kobject *mk;
762 attribute = to_module_attr(attr);
763 mk = to_module_kobject(kobj);
765 if (!attribute->store)
768 ret = attribute->store(attribute, mk->mod, buf, len);
773 static const struct sysfs_ops module_sysfs_ops = {
774 .show = module_attr_show,
775 .store = module_attr_store,
778 static int uevent_filter(struct kset *kset, struct kobject *kobj)
780 struct kobj_type *ktype = get_ktype(kobj);
782 if (ktype == &module_ktype)
787 static const struct kset_uevent_ops module_uevent_ops = {
788 .filter = uevent_filter,
791 struct kset *module_kset;
792 int module_sysfs_initialized;
794 struct kobj_type module_ktype = {
795 .sysfs_ops = &module_sysfs_ops,
799 * param_sysfs_init - wrapper for built-in params support
801 static int __init param_sysfs_init(void)
803 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
805 printk(KERN_WARNING "%s (%d): error creating kset\n",
809 module_sysfs_initialized = 1;
811 param_sysfs_builtin();
815 subsys_initcall(param_sysfs_init);
817 #endif /* CONFIG_SYSFS */