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>
30 #define DEBUGP(fmt, a...)
33 static struct kobj_type module_ktype;
35 static inline char dash2underscore(char c)
42 static inline int parameq(const char *input, const char *paramname)
45 for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
51 static int parse_one(char *param,
53 struct kernel_param *params,
55 int (*handle_unknown)(char *param, char *val))
60 for (i = 0; i < num_params; i++) {
61 if (parameq(param, params[i].name)) {
62 DEBUGP("They are equal! Calling %p\n",
64 return params[i].set(val, ¶ms[i]);
69 DEBUGP("Unknown argument: calling %p\n", handle_unknown);
70 return handle_unknown(param, val);
73 DEBUGP("Unknown argument `%s'\n", param);
77 /* You can use " around spaces, but can't escape ". */
78 /* Hyphens and underscores equivalent in parameter names. */
79 static char *next_arg(char *args, char **param, char **val)
81 unsigned int i, equals = 0;
82 int in_quote = 0, quoted = 0;
91 for (i = 0; args[i]; i++) {
92 if (args[i] == ' ' && !in_quote)
107 *val = args + equals + 1;
109 /* Don't include quotes in value. */
112 if (args[i-1] == '"')
115 if (quoted && args[i-1] == '"')
125 /* Chew up trailing spaces. */
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 */
148 int irq_was_disabled;
150 args = next_arg(args, ¶m, &val);
151 irq_was_disabled = irqs_disabled();
152 ret = parse_one(param, val, params, num, unknown);
153 if (irq_was_disabled && !irqs_disabled()) {
154 printk(KERN_WARNING "parse_args(): option '%s' enabled "
159 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
164 "%s: `%s' too large for parameter `%s'\n",
165 name, val ?: "", param);
171 "%s: `%s' invalid for parameter `%s'\n",
172 name, val ?: "", param);
181 /* Lazy bastard, eh? */
182 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
183 int param_set_##name(const char *val, struct kernel_param *kp) \
188 if (!val) return -EINVAL; \
189 l = strtolfn(val, &endp, 0); \
190 if (endp == val || ((type)l != l)) \
192 *((type *)kp->arg) = l; \
195 int param_get_##name(char *buffer, struct kernel_param *kp) \
197 return sprintf(buffer, format, *((type *)kp->arg)); \
200 STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, simple_strtoul);
201 STANDARD_PARAM_DEF(short, short, "%hi", long, simple_strtol);
202 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, simple_strtoul);
203 STANDARD_PARAM_DEF(int, int, "%i", long, simple_strtol);
204 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, simple_strtoul);
205 STANDARD_PARAM_DEF(long, long, "%li", long, simple_strtol);
206 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, simple_strtoul);
208 int param_set_charp(const char *val, struct kernel_param *kp)
211 printk(KERN_ERR "%s: string parameter expected\n",
216 if (strlen(val) > 1024) {
217 printk(KERN_ERR "%s: string parameter too long\n",
222 *(char **)kp->arg = (char *)val;
226 int param_get_charp(char *buffer, struct kernel_param *kp)
228 return sprintf(buffer, "%s", *((char **)kp->arg));
231 int param_set_bool(const char *val, struct kernel_param *kp)
233 /* No equals means "set"... */
236 /* One of =[yYnN01] */
238 case 'y': case 'Y': case '1':
241 case 'n': case 'N': case '0':
248 int param_get_bool(char *buffer, struct kernel_param *kp)
250 /* Y and N chosen as being relatively non-coder friendly */
251 return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'Y' : 'N');
254 int param_set_invbool(const char *val, struct kernel_param *kp)
257 struct kernel_param dummy;
259 dummy.arg = &boolval;
260 ret = param_set_bool(val, &dummy);
262 *(int *)kp->arg = !boolval;
266 int param_get_invbool(char *buffer, struct kernel_param *kp)
268 return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'N' : 'Y');
271 /* We break the rule and mangle the string. */
272 static int param_array(const char *name,
274 unsigned int min, unsigned int max,
275 void *elem, int elemsize,
276 int (*set)(const char *, struct kernel_param *kp),
280 struct kernel_param kp;
283 /* Get the name right for errors. */
287 /* No equals sign? */
289 printk(KERN_ERR "%s: expects arguments\n", name);
294 /* We expect a comma-separated list of values. */
299 printk(KERN_ERR "%s: can only take %i arguments\n",
303 len = strcspn(val, ",");
305 /* nul-terminate and parse */
307 ((char *)val)[len] = '\0';
315 } while (save == ',');
318 printk(KERN_ERR "%s: needs at least %i arguments\n",
325 int param_array_set(const char *val, struct kernel_param *kp)
327 const struct kparam_array *arr = kp->arr;
328 unsigned int temp_num;
330 return param_array(kp->name, val, 1, arr->max, arr->elem,
331 arr->elemsize, arr->set, arr->num ?: &temp_num);
334 int param_array_get(char *buffer, struct kernel_param *kp)
337 const struct kparam_array *arr = kp->arr;
338 struct kernel_param p;
341 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
344 p.arg = arr->elem + arr->elemsize * i;
345 ret = arr->get(buffer + off, &p);
354 int param_set_copystring(const char *val, struct kernel_param *kp)
356 const struct kparam_string *kps = kp->str;
359 printk(KERN_ERR "%s: missing param set value\n", kp->name);
362 if (strlen(val)+1 > kps->maxlen) {
363 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
364 kp->name, kps->maxlen-1);
367 strcpy(kps->string, val);
371 int param_get_string(char *buffer, struct kernel_param *kp)
373 const struct kparam_string *kps = kp->str;
374 return strlcpy(buffer, kps->string, kps->maxlen);
377 /* sysfs output in /sys/modules/XYZ/parameters/ */
379 extern struct kernel_param __start___param[], __stop___param[];
381 #define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
383 struct param_attribute
385 struct module_attribute mattr;
386 struct kernel_param *param;
389 struct module_param_attrs
391 struct attribute_group grp;
392 struct param_attribute attrs[0];
396 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
398 static ssize_t param_attr_show(struct module_attribute *mattr,
399 struct module *mod, char *buf)
402 struct param_attribute *attribute = to_param_attr(mattr);
404 if (!attribute->param->get)
407 count = attribute->param->get(buf, attribute->param);
415 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
416 static ssize_t param_attr_store(struct module_attribute *mattr,
417 struct module *owner,
418 const char *buf, size_t len)
421 struct param_attribute *attribute = to_param_attr(mattr);
423 if (!attribute->param->set)
426 err = attribute->param->set(buf, attribute->param);
433 #ifdef CONFIG_MODULES
436 #define __modinit __init
441 * param_sysfs_setup - setup sysfs support for one module or KBUILD_MODNAME
442 * @mk: struct module_kobject (contains parent kobject)
443 * @kparam: array of struct kernel_param, the actual parameter definitions
444 * @num_params: number of entries in array
445 * @name_skip: offset where the parameter name start in kparam[].name. Needed for built-in "modules"
447 * Create a kobject for a (per-module) group of parameters, and create files
448 * in sysfs. A pointer to the param_kobject is returned on success,
449 * NULL if there's no parameter to export, or other ERR_PTR(err).
451 static __modinit struct module_param_attrs *
452 param_sysfs_setup(struct module_kobject *mk,
453 struct kernel_param *kparam,
454 unsigned int num_params,
455 unsigned int name_skip)
457 struct module_param_attrs *mp;
458 unsigned int valid_attrs = 0;
459 unsigned int i, size[2];
460 struct param_attribute *pattr;
461 struct attribute **gattr;
464 for (i=0; i<num_params; i++) {
472 size[0] = ALIGN(sizeof(*mp) +
473 valid_attrs * sizeof(mp->attrs[0]),
474 sizeof(mp->grp.attrs[0]));
475 size[1] = (valid_attrs + 1) * sizeof(mp->grp.attrs[0]);
477 mp = kmalloc(size[0] + size[1], GFP_KERNEL);
479 return ERR_PTR(-ENOMEM);
481 mp->grp.name = "parameters";
482 mp->grp.attrs = (void *)mp + size[0];
484 pattr = &mp->attrs[0];
485 gattr = &mp->grp.attrs[0];
486 for (i = 0; i < num_params; i++) {
487 struct kernel_param *kp = &kparam[i];
490 pattr->mattr.show = param_attr_show;
491 pattr->mattr.store = param_attr_store;
492 pattr->mattr.attr.name = (char *)&kp->name[name_skip];
493 pattr->mattr.attr.mode = kp->perm;
494 *(gattr++) = &(pattr++)->mattr.attr;
499 if ((err = sysfs_create_group(&mk->kobj, &mp->grp))) {
506 #ifdef CONFIG_MODULES
508 * module_param_sysfs_setup - setup sysfs support for one module
510 * @kparam: module parameters (array)
511 * @num_params: number of module parameters
513 * Adds sysfs entries for module parameters, and creates a link from
514 * /sys/module/[mod->name]/parameters to /sys/parameters/[mod->name]/
516 int module_param_sysfs_setup(struct module *mod,
517 struct kernel_param *kparam,
518 unsigned int num_params)
520 struct module_param_attrs *mp;
522 mp = param_sysfs_setup(&mod->mkobj, kparam, num_params, 0);
526 mod->param_attrs = mp;
531 * module_param_sysfs_remove - remove sysfs support for one module
534 * Remove sysfs entries for module parameters and the corresponding
537 void module_param_sysfs_remove(struct module *mod)
539 if (mod->param_attrs) {
540 sysfs_remove_group(&mod->mkobj.kobj,
541 &mod->param_attrs->grp);
542 /* We are positive that no one is using any param
543 * attrs at this point. Deallocate immediately. */
544 kfree(mod->param_attrs);
545 mod->param_attrs = NULL;
551 * kernel_param_sysfs_setup - wrapper for built-in params support
553 static void __init kernel_param_sysfs_setup(const char *name,
554 struct kernel_param *kparam,
555 unsigned int num_params,
556 unsigned int name_skip)
558 struct module_kobject *mk;
561 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
564 mk->mod = THIS_MODULE;
565 mk->kobj.kset = &module_subsys;
566 mk->kobj.ktype = &module_ktype;
567 kobject_set_name(&mk->kobj, name);
568 kobject_init(&mk->kobj);
569 ret = kobject_add(&mk->kobj);
571 printk(KERN_ERR "Module '%s' failed to be added to sysfs, "
572 "error number %d\n", name, ret);
573 printk(KERN_ERR "The system will be unstable now.\n");
576 param_sysfs_setup(mk, kparam, num_params, name_skip);
577 kobject_uevent(&mk->kobj, KOBJ_ADD);
581 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
583 * Add module_parameters to sysfs for "modules" built into the kernel.
585 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
586 * "parameter" name is stored behind a dot in kernel_param->name. So,
587 * extract the "module" name for all built-in kernel_param-eters,
588 * and for all who have the same, call kernel_param_sysfs_setup.
590 static void __init param_sysfs_builtin(void)
592 struct kernel_param *kp, *kp_begin = NULL;
593 unsigned int i, name_len, count = 0;
594 char modname[MAX_KBUILD_MODNAME + 1] = "";
596 for (i=0; i < __stop___param - __start___param; i++) {
600 kp = &__start___param[i];
602 min_t(size_t, MAX_KBUILD_MODNAME, strlen(kp->name));
604 dot = memchr(kp->name, '.', max_name_len);
606 DEBUGP("couldn't find period in first %d characters "
607 "of %s\n", MAX_KBUILD_MODNAME, kp->name);
610 name_len = dot - kp->name;
612 /* new kbuild_modname? */
613 if (strlen(modname) != name_len
614 || strncmp(modname, kp->name, name_len) != 0) {
615 /* add a new kobject for previous kernel_params. */
617 kernel_param_sysfs_setup(modname,
622 strncpy(modname, kp->name, name_len);
623 modname[name_len] = '\0';
630 /* last kernel_params need to be registered as well */
632 kernel_param_sysfs_setup(modname, kp_begin, count,
637 /* module-related sysfs stuff */
639 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
640 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
642 static ssize_t module_attr_show(struct kobject *kobj,
643 struct attribute *attr,
646 struct module_attribute *attribute;
647 struct module_kobject *mk;
650 attribute = to_module_attr(attr);
651 mk = to_module_kobject(kobj);
653 if (!attribute->show)
656 ret = attribute->show(attribute, mk->mod, buf);
661 static ssize_t module_attr_store(struct kobject *kobj,
662 struct attribute *attr,
663 const char *buf, size_t len)
665 struct module_attribute *attribute;
666 struct module_kobject *mk;
669 attribute = to_module_attr(attr);
670 mk = to_module_kobject(kobj);
672 if (!attribute->store)
675 ret = attribute->store(attribute, mk->mod, buf, len);
680 static struct sysfs_ops module_sysfs_ops = {
681 .show = module_attr_show,
682 .store = module_attr_store,
685 static int uevent_filter(struct kset *kset, struct kobject *kobj)
687 struct kobj_type *ktype = get_ktype(kobj);
689 if (ktype == &module_ktype)
694 static struct kset_uevent_ops module_uevent_ops = {
695 .filter = uevent_filter,
698 decl_subsys(module, &module_uevent_ops);
699 int module_sysfs_initialized;
701 static void module_release(struct kobject *kobj)
704 * Stupid empty release function to allow the memory for the kobject to
705 * be properly cleaned up. This will not need to be present for 2.6.25
706 * with the upcoming kobject core rework.
710 static struct kobj_type module_ktype = {
711 .sysfs_ops = &module_sysfs_ops,
712 .release = module_release,
716 * param_sysfs_init - wrapper for built-in params support
718 static int __init param_sysfs_init(void)
722 ret = subsystem_register(&module_subsys);
724 printk(KERN_WARNING "%s (%d): subsystem_register error: %d\n",
725 __FILE__, __LINE__, ret);
728 module_sysfs_initialized = 1;
730 param_sysfs_builtin();
734 subsys_initcall(param_sysfs_init);
738 static struct sysfs_ops module_sysfs_ops = {
745 EXPORT_SYMBOL(param_set_byte);
746 EXPORT_SYMBOL(param_get_byte);
747 EXPORT_SYMBOL(param_set_short);
748 EXPORT_SYMBOL(param_get_short);
749 EXPORT_SYMBOL(param_set_ushort);
750 EXPORT_SYMBOL(param_get_ushort);
751 EXPORT_SYMBOL(param_set_int);
752 EXPORT_SYMBOL(param_get_int);
753 EXPORT_SYMBOL(param_set_uint);
754 EXPORT_SYMBOL(param_get_uint);
755 EXPORT_SYMBOL(param_set_long);
756 EXPORT_SYMBOL(param_get_long);
757 EXPORT_SYMBOL(param_set_ulong);
758 EXPORT_SYMBOL(param_get_ulong);
759 EXPORT_SYMBOL(param_set_charp);
760 EXPORT_SYMBOL(param_get_charp);
761 EXPORT_SYMBOL(param_set_bool);
762 EXPORT_SYMBOL(param_get_bool);
763 EXPORT_SYMBOL(param_set_invbool);
764 EXPORT_SYMBOL(param_get_invbool);
765 EXPORT_SYMBOL(param_array_set);
766 EXPORT_SYMBOL(param_array_get);
767 EXPORT_SYMBOL(param_set_copystring);
768 EXPORT_SYMBOL(param_get_string);