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].set != param_set_bool)
64 DEBUGP("They are equal! Calling %p\n",
66 return params[i].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, 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, struct kernel_param *kp) \
195 return sprintf(buffer, format, *((type *)kp->arg)); \
198 STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
199 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
200 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
201 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
202 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
203 STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
204 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
206 int param_set_charp(const char *val, struct kernel_param *kp)
208 if (strlen(val) > 1024) {
209 printk(KERN_ERR "%s: string parameter too long\n",
214 /* This is a hack. We can't need to strdup in early boot, and we
215 * don't need to; this mangled commandline is preserved. */
216 if (slab_is_available()) {
217 *(char **)kp->arg = kstrdup(val, GFP_KERNEL);
218 if (!*(char **)kp->arg)
221 *(const char **)kp->arg = val;
226 int param_get_charp(char *buffer, struct kernel_param *kp)
228 return sprintf(buffer, "%s", *((char **)kp->arg));
231 /* Actually could be a bool or an int, for historical reasons. */
232 int param_set_bool(const char *val, struct kernel_param *kp)
236 /* No equals means "set"... */
239 /* One of =[yYnN01] */
241 case 'y': case 'Y': case '1':
244 case 'n': case 'N': case '0':
251 if (kp->flags & KPARAM_ISBOOL)
252 *(bool *)kp->arg = v;
258 int param_get_bool(char *buffer, struct kernel_param *kp)
261 if (kp->flags & KPARAM_ISBOOL)
262 val = *(bool *)kp->arg;
264 val = *(int *)kp->arg;
266 /* Y and N chosen as being relatively non-coder friendly */
267 return sprintf(buffer, "%c", val ? 'Y' : 'N');
270 /* This one must be bool. */
271 int param_set_invbool(const char *val, struct kernel_param *kp)
275 struct kernel_param dummy;
277 dummy.arg = &boolval;
278 dummy.flags = KPARAM_ISBOOL;
279 ret = param_set_bool(val, &dummy);
281 *(bool *)kp->arg = !boolval;
285 int param_get_invbool(char *buffer, struct kernel_param *kp)
287 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
290 /* We break the rule and mangle the string. */
291 static int param_array(const char *name,
293 unsigned int min, unsigned int max,
294 void *elem, int elemsize,
295 int (*set)(const char *, struct kernel_param *kp),
300 struct kernel_param kp;
303 /* Get the name right for errors. */
309 /* We expect a comma-separated list of values. */
314 printk(KERN_ERR "%s: can only take %i arguments\n",
318 len = strcspn(val, ",");
320 /* nul-terminate and parse */
322 ((char *)val)[len] = '\0';
330 } while (save == ',');
333 printk(KERN_ERR "%s: needs at least %i arguments\n",
340 int param_array_set(const char *val, struct kernel_param *kp)
342 const struct kparam_array *arr = kp->arr;
343 unsigned int temp_num;
345 return param_array(kp->name, val, 1, arr->max, arr->elem,
346 arr->elemsize, arr->set, kp->flags,
347 arr->num ?: &temp_num);
350 int param_array_get(char *buffer, struct kernel_param *kp)
353 const struct kparam_array *arr = kp->arr;
354 struct kernel_param p;
357 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
360 p.arg = arr->elem + arr->elemsize * i;
361 ret = arr->get(buffer + off, &p);
370 int param_set_copystring(const char *val, struct kernel_param *kp)
372 const struct kparam_string *kps = kp->str;
374 if (strlen(val)+1 > kps->maxlen) {
375 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
376 kp->name, kps->maxlen-1);
379 strcpy(kps->string, val);
383 int param_get_string(char *buffer, struct kernel_param *kp)
385 const struct kparam_string *kps = kp->str;
386 return strlcpy(buffer, kps->string, kps->maxlen);
389 /* sysfs output in /sys/modules/XYZ/parameters/ */
390 #define to_module_attr(n) container_of(n, struct module_attribute, attr)
391 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
393 extern struct kernel_param __start___param[], __stop___param[];
395 struct param_attribute
397 struct module_attribute mattr;
398 struct kernel_param *param;
401 struct module_param_attrs
404 struct attribute_group grp;
405 struct param_attribute attrs[0];
409 #define to_param_attr(n) container_of(n, struct param_attribute, mattr)
411 static ssize_t param_attr_show(struct module_attribute *mattr,
412 struct module *mod, char *buf)
415 struct param_attribute *attribute = to_param_attr(mattr);
417 if (!attribute->param->get)
420 count = attribute->param->get(buf, attribute->param);
428 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
429 static ssize_t param_attr_store(struct module_attribute *mattr,
430 struct module *owner,
431 const char *buf, size_t len)
434 struct param_attribute *attribute = to_param_attr(mattr);
436 if (!attribute->param->set)
439 err = attribute->param->set(buf, attribute->param);
446 #ifdef CONFIG_MODULES
449 #define __modinit __init
454 * add_sysfs_param - add a parameter to sysfs
455 * @mk: struct module_kobject
456 * @kparam: the actual parameter definition to add to sysfs
457 * @name: name of parameter
459 * Create a kobject if for a (per-module) parameter if mp NULL, and
460 * create file in sysfs. Returns an error on out of memory. Always cleans up
461 * if there's an error.
463 static __modinit int add_sysfs_param(struct module_kobject *mk,
464 struct kernel_param *kp,
467 struct module_param_attrs *new;
468 struct attribute **attrs;
471 /* We don't bother calling this with invisible parameters. */
479 attrs = mk->mp->grp.attrs;
483 new = krealloc(mk->mp,
484 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
491 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
497 /* Sysfs wants everything zeroed. */
498 memset(new, 0, sizeof(*new));
499 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
500 memset(&attrs[num], 0, sizeof(attrs[num]));
501 new->grp.name = "parameters";
502 new->grp.attrs = attrs;
504 /* Tack new one on the end. */
505 sysfs_attr_init(&new->attrs[num].mattr.attr);
506 new->attrs[num].param = kp;
507 new->attrs[num].mattr.show = param_attr_show;
508 new->attrs[num].mattr.store = param_attr_store;
509 new->attrs[num].mattr.attr.name = (char *)name;
510 new->attrs[num].mattr.attr.mode = kp->perm;
513 /* Fix up all the pointers, since krealloc can move us */
514 for (num = 0; num < new->num; num++)
515 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
516 new->grp.attrs[num] = NULL;
528 #ifdef CONFIG_MODULES
529 static void free_module_param_attrs(struct module_kobject *mk)
531 kfree(mk->mp->grp.attrs);
537 * module_param_sysfs_setup - setup sysfs support for one module
539 * @kparam: module parameters (array)
540 * @num_params: number of module parameters
542 * Adds sysfs entries for module parameters under
543 * /sys/module/[mod->name]/parameters/
545 int module_param_sysfs_setup(struct module *mod,
546 struct kernel_param *kparam,
547 unsigned int num_params)
552 for (i = 0; i < num_params; i++) {
553 if (kparam[i].perm == 0)
555 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
564 /* Create the param group. */
565 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
567 free_module_param_attrs(&mod->mkobj);
572 * module_param_sysfs_remove - remove sysfs support for one module
575 * Remove sysfs entries for module parameters and the corresponding
578 void module_param_sysfs_remove(struct module *mod)
581 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
582 /* We are positive that no one is using any param
583 * attrs at this point. Deallocate immediately. */
584 free_module_param_attrs(&mod->mkobj);
589 void destroy_params(const struct kernel_param *params, unsigned num)
591 /* FIXME: This should free kmalloced charp parameters. It doesn't. */
594 static void __init kernel_add_sysfs_param(const char *name,
595 struct kernel_param *kparam,
596 unsigned int name_skip)
598 struct module_kobject *mk;
599 struct kobject *kobj;
602 kobj = kset_find_obj(module_kset, name);
604 /* We already have one. Remove params so we can add more. */
605 mk = to_module_kobject(kobj);
606 /* We need to remove it before adding parameters. */
607 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
609 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
612 mk->mod = THIS_MODULE;
613 mk->kobj.kset = module_kset;
614 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
617 kobject_put(&mk->kobj);
618 printk(KERN_ERR "Module '%s' failed add to sysfs, "
619 "error number %d\n", name, err);
620 printk(KERN_ERR "The system will be unstable now.\n");
623 /* So that exit path is even. */
624 kobject_get(&mk->kobj);
627 /* These should not fail at boot. */
628 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
630 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
632 kobject_uevent(&mk->kobj, KOBJ_ADD);
633 kobject_put(&mk->kobj);
637 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
639 * Add module_parameters to sysfs for "modules" built into the kernel.
641 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
642 * "parameter" name is stored behind a dot in kernel_param->name. So,
643 * extract the "module" name for all built-in kernel_param-eters,
644 * and for all who have the same, call kernel_add_sysfs_param.
646 static void __init param_sysfs_builtin(void)
648 struct kernel_param *kp;
649 unsigned int name_len;
650 char modname[MODULE_NAME_LEN];
652 for (kp = __start___param; kp < __stop___param; kp++) {
658 dot = strchr(kp->name, '.');
660 /* This happens for core_param() */
661 strcpy(modname, "kernel");
664 name_len = dot - kp->name + 1;
665 strlcpy(modname, kp->name, name_len);
667 kernel_add_sysfs_param(modname, kp, name_len);
672 /* module-related sysfs stuff */
674 static ssize_t module_attr_show(struct kobject *kobj,
675 struct attribute *attr,
678 struct module_attribute *attribute;
679 struct module_kobject *mk;
682 attribute = to_module_attr(attr);
683 mk = to_module_kobject(kobj);
685 if (!attribute->show)
688 ret = attribute->show(attribute, mk->mod, buf);
693 static ssize_t module_attr_store(struct kobject *kobj,
694 struct attribute *attr,
695 const char *buf, size_t len)
697 struct module_attribute *attribute;
698 struct module_kobject *mk;
701 attribute = to_module_attr(attr);
702 mk = to_module_kobject(kobj);
704 if (!attribute->store)
707 ret = attribute->store(attribute, mk->mod, buf, len);
712 static const struct sysfs_ops module_sysfs_ops = {
713 .show = module_attr_show,
714 .store = module_attr_store,
717 static int uevent_filter(struct kset *kset, struct kobject *kobj)
719 struct kobj_type *ktype = get_ktype(kobj);
721 if (ktype == &module_ktype)
726 static const struct kset_uevent_ops module_uevent_ops = {
727 .filter = uevent_filter,
730 struct kset *module_kset;
731 int module_sysfs_initialized;
733 struct kobj_type module_ktype = {
734 .sysfs_ops = &module_sysfs_ops,
738 * param_sysfs_init - wrapper for built-in params support
740 static int __init param_sysfs_init(void)
742 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
744 printk(KERN_WARNING "%s (%d): error creating kset\n",
748 module_sysfs_initialized = 1;
750 param_sysfs_builtin();
754 subsys_initcall(param_sysfs_init);
756 #endif /* CONFIG_SYSFS */
758 EXPORT_SYMBOL(param_set_byte);
759 EXPORT_SYMBOL(param_get_byte);
760 EXPORT_SYMBOL(param_set_short);
761 EXPORT_SYMBOL(param_get_short);
762 EXPORT_SYMBOL(param_set_ushort);
763 EXPORT_SYMBOL(param_get_ushort);
764 EXPORT_SYMBOL(param_set_int);
765 EXPORT_SYMBOL(param_get_int);
766 EXPORT_SYMBOL(param_set_uint);
767 EXPORT_SYMBOL(param_get_uint);
768 EXPORT_SYMBOL(param_set_long);
769 EXPORT_SYMBOL(param_get_long);
770 EXPORT_SYMBOL(param_set_ulong);
771 EXPORT_SYMBOL(param_get_ulong);
772 EXPORT_SYMBOL(param_set_charp);
773 EXPORT_SYMBOL(param_get_charp);
774 EXPORT_SYMBOL(param_set_bool);
775 EXPORT_SYMBOL(param_get_bool);
776 EXPORT_SYMBOL(param_set_invbool);
777 EXPORT_SYMBOL(param_get_invbool);
778 EXPORT_SYMBOL(param_array_set);
779 EXPORT_SYMBOL(param_array_get);
780 EXPORT_SYMBOL(param_set_copystring);
781 EXPORT_SYMBOL(param_get_string);