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 inline char 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 */
146 int irq_was_disabled;
148 args = next_arg(args, ¶m, &val);
149 irq_was_disabled = irqs_disabled();
150 ret = parse_one(param, val, params, num, unknown);
151 if (irq_was_disabled && !irqs_disabled()) {
152 printk(KERN_WARNING "parse_args(): option '%s' enabled "
157 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
162 "%s: `%s' too large for parameter `%s'\n",
163 name, val ?: "", param);
169 "%s: `%s' invalid for parameter `%s'\n",
170 name, val ?: "", param);
179 /* Lazy bastard, eh? */
180 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
181 int param_set_##name(const char *val, struct kernel_param *kp) \
186 if (!val) return -EINVAL; \
187 l = strtolfn(val, &endp, 0); \
188 if (endp == val || ((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, simple_strtoul);
199 STANDARD_PARAM_DEF(short, short, "%hi", long, simple_strtol);
200 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, simple_strtoul);
201 STANDARD_PARAM_DEF(int, int, "%i", long, simple_strtol);
202 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, simple_strtoul);
203 STANDARD_PARAM_DEF(long, long, "%li", long, simple_strtol);
204 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, simple_strtoul);
206 int param_set_charp(const char *val, struct kernel_param *kp)
209 printk(KERN_ERR "%s: string parameter expected\n",
214 if (strlen(val) > 1024) {
215 printk(KERN_ERR "%s: string parameter too long\n",
220 *(char **)kp->arg = (char *)val;
224 int param_get_charp(char *buffer, struct kernel_param *kp)
226 return sprintf(buffer, "%s", *((char **)kp->arg));
229 int param_set_bool(const char *val, struct kernel_param *kp)
231 /* No equals means "set"... */
234 /* One of =[yYnN01] */
236 case 'y': case 'Y': case '1':
239 case 'n': case 'N': case '0':
246 int param_get_bool(char *buffer, struct kernel_param *kp)
248 /* Y and N chosen as being relatively non-coder friendly */
249 return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'Y' : 'N');
252 int param_set_invbool(const char *val, struct kernel_param *kp)
255 struct kernel_param dummy = { .arg = &boolval };
257 ret = param_set_bool(val, &dummy);
259 *(int *)kp->arg = !boolval;
263 int param_get_invbool(char *buffer, struct kernel_param *kp)
266 struct kernel_param dummy = { .arg = &val };
268 val = !*(int *)kp->arg;
269 return param_get_bool(buffer, &dummy);
272 /* We cheat here and temporarily mangle the string. */
273 static int param_array(const char *name,
275 unsigned int min, unsigned int max,
276 void *elem, int elemsize,
277 int (*set)(const char *, struct kernel_param *kp),
281 struct kernel_param kp;
284 /* Get the name right for errors. */
288 /* No equals sign? */
290 printk(KERN_ERR "%s: expects arguments\n", name);
295 /* We expect a comma-separated list of values. */
300 printk(KERN_ERR "%s: can only take %i arguments\n",
304 len = strcspn(val, ",");
306 /* nul-terminate and parse */
308 ((char *)val)[len] = '\0';
316 } while (save == ',');
319 printk(KERN_ERR "%s: needs at least %i arguments\n",
326 int param_array_set(const char *val, struct kernel_param *kp)
328 struct kparam_array *arr = kp->arg;
329 unsigned int temp_num;
331 return param_array(kp->name, val, 1, arr->max, arr->elem,
332 arr->elemsize, arr->set, arr->num ?: &temp_num);
335 int param_array_get(char *buffer, struct kernel_param *kp)
338 struct kparam_array *arr = kp->arg;
339 struct kernel_param p;
342 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
345 p.arg = arr->elem + arr->elemsize * i;
346 ret = arr->get(buffer + off, &p);
355 int param_set_copystring(const char *val, struct kernel_param *kp)
357 struct kparam_string *kps = kp->arg;
360 printk(KERN_ERR "%s: missing param set value\n", kp->name);
363 if (strlen(val)+1 > kps->maxlen) {
364 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
365 kp->name, kps->maxlen-1);
368 strcpy(kps->string, val);
372 int param_get_string(char *buffer, struct kernel_param *kp)
374 struct kparam_string *kps = kp->arg;
375 return strlcpy(buffer, kps->string, kps->maxlen);
378 /* sysfs output in /sys/modules/XYZ/parameters/ */
380 extern struct kernel_param __start___param[], __stop___param[];
382 #define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
384 struct param_attribute
386 struct module_attribute mattr;
387 struct kernel_param *param;
390 struct module_param_attrs
392 struct attribute_group grp;
393 struct param_attribute attrs[0];
397 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
399 static ssize_t param_attr_show(struct module_attribute *mattr,
400 struct module *mod, char *buf)
403 struct param_attribute *attribute = to_param_attr(mattr);
405 if (!attribute->param->get)
408 count = attribute->param->get(buf, attribute->param);
416 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
417 static ssize_t param_attr_store(struct module_attribute *mattr,
418 struct module *owner,
419 const char *buf, size_t len)
422 struct param_attribute *attribute = to_param_attr(mattr);
424 if (!attribute->param->set)
427 err = attribute->param->set(buf, attribute->param);
434 #ifdef CONFIG_MODULES
437 #define __modinit __init
442 * param_sysfs_setup - setup sysfs support for one module or KBUILD_MODNAME
443 * @mk: struct module_kobject (contains parent kobject)
444 * @kparam: array of struct kernel_param, the actual parameter definitions
445 * @num_params: number of entries in array
446 * @name_skip: offset where the parameter name start in kparam[].name. Needed for built-in "modules"
448 * Create a kobject for a (per-module) group of parameters, and create files
449 * in sysfs. A pointer to the param_kobject is returned on success,
450 * NULL if there's no parameter to export, or other ERR_PTR(err).
452 static __modinit struct module_param_attrs *
453 param_sysfs_setup(struct module_kobject *mk,
454 struct kernel_param *kparam,
455 unsigned int num_params,
456 unsigned int name_skip)
458 struct module_param_attrs *mp;
459 unsigned int valid_attrs = 0;
460 unsigned int i, size[2];
461 struct param_attribute *pattr;
462 struct attribute **gattr;
465 for (i=0; i<num_params; i++) {
473 size[0] = ALIGN(sizeof(*mp) +
474 valid_attrs * sizeof(mp->attrs[0]),
475 sizeof(mp->grp.attrs[0]));
476 size[1] = (valid_attrs + 1) * sizeof(mp->grp.attrs[0]);
478 mp = kmalloc(size[0] + size[1], GFP_KERNEL);
480 return ERR_PTR(-ENOMEM);
482 mp->grp.name = "parameters";
483 mp->grp.attrs = (void *)mp + size[0];
485 pattr = &mp->attrs[0];
486 gattr = &mp->grp.attrs[0];
487 for (i = 0; i < num_params; i++) {
488 struct kernel_param *kp = &kparam[i];
491 pattr->mattr.show = param_attr_show;
492 pattr->mattr.store = param_attr_store;
493 pattr->mattr.attr.name = (char *)&kp->name[name_skip];
494 pattr->mattr.attr.owner = mk->mod;
495 pattr->mattr.attr.mode = kp->perm;
496 *(gattr++) = &(pattr++)->mattr.attr;
501 if ((err = sysfs_create_group(&mk->kobj, &mp->grp))) {
508 #ifdef CONFIG_MODULES
510 * module_param_sysfs_setup - setup sysfs support for one module
512 * @kparam: module parameters (array)
513 * @num_params: number of module parameters
515 * Adds sysfs entries for module parameters, and creates a link from
516 * /sys/module/[mod->name]/parameters to /sys/parameters/[mod->name]/
518 int module_param_sysfs_setup(struct module *mod,
519 struct kernel_param *kparam,
520 unsigned int num_params)
522 struct module_param_attrs *mp;
524 mp = param_sysfs_setup(&mod->mkobj, kparam, num_params, 0);
528 mod->param_attrs = mp;
533 * module_param_sysfs_remove - remove sysfs support for one module
536 * Remove sysfs entries for module parameters and the corresponding
539 void module_param_sysfs_remove(struct module *mod)
541 if (mod->param_attrs) {
542 sysfs_remove_group(&mod->mkobj.kobj,
543 &mod->param_attrs->grp);
544 /* We are positive that no one is using any param
545 * attrs at this point. Deallocate immediately. */
546 kfree(mod->param_attrs);
547 mod->param_attrs = NULL;
553 * kernel_param_sysfs_setup - wrapper for built-in params support
555 static void __init kernel_param_sysfs_setup(const char *name,
556 struct kernel_param *kparam,
557 unsigned int num_params,
558 unsigned int name_skip)
560 struct module_kobject *mk;
563 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
566 mk->mod = THIS_MODULE;
567 kobj_set_kset_s(mk, module_subsys);
568 kobject_set_name(&mk->kobj, name);
569 kobject_init(&mk->kobj);
570 ret = kobject_add(&mk->kobj);
572 param_sysfs_setup(mk, kparam, num_params, name_skip);
573 kobject_uevent(&mk->kobj, KOBJ_ADD);
577 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
579 * Add module_parameters to sysfs for "modules" built into the kernel.
581 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
582 * "parameter" name is stored behind a dot in kernel_param->name. So,
583 * extract the "module" name for all built-in kernel_param-eters,
584 * and for all who have the same, call kernel_param_sysfs_setup.
586 static void __init param_sysfs_builtin(void)
588 struct kernel_param *kp, *kp_begin = NULL;
589 unsigned int i, name_len, count = 0;
590 char modname[MAX_KBUILD_MODNAME + 1] = "";
592 for (i=0; i < __stop___param - __start___param; i++) {
595 kp = &__start___param[i];
597 /* We do not handle args without periods. */
598 dot = memchr(kp->name, '.', MAX_KBUILD_MODNAME);
600 DEBUGP("couldn't find period in %s\n", kp->name);
603 name_len = dot - kp->name;
605 /* new kbuild_modname? */
606 if (strlen(modname) != name_len
607 || strncmp(modname, kp->name, name_len) != 0) {
608 /* add a new kobject for previous kernel_params. */
610 kernel_param_sysfs_setup(modname,
615 strncpy(modname, kp->name, name_len);
616 modname[name_len] = '\0';
623 /* last kernel_params need to be registered as well */
625 kernel_param_sysfs_setup(modname, kp_begin, count,
630 /* module-related sysfs stuff */
632 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
633 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
635 static ssize_t module_attr_show(struct kobject *kobj,
636 struct attribute *attr,
639 struct module_attribute *attribute;
640 struct module_kobject *mk;
643 attribute = to_module_attr(attr);
644 mk = to_module_kobject(kobj);
646 if (!attribute->show)
649 ret = attribute->show(attribute, mk->mod, buf);
654 static ssize_t module_attr_store(struct kobject *kobj,
655 struct attribute *attr,
656 const char *buf, size_t len)
658 struct module_attribute *attribute;
659 struct module_kobject *mk;
662 attribute = to_module_attr(attr);
663 mk = to_module_kobject(kobj);
665 if (!attribute->store)
668 ret = attribute->store(attribute, mk->mod, buf, len);
673 static struct sysfs_ops module_sysfs_ops = {
674 .show = module_attr_show,
675 .store = module_attr_store,
678 static struct kobj_type module_ktype;
680 static int uevent_filter(struct kset *kset, struct kobject *kobj)
682 struct kobj_type *ktype = get_ktype(kobj);
684 if (ktype == &module_ktype)
689 static struct kset_uevent_ops module_uevent_ops = {
690 .filter = uevent_filter,
693 decl_subsys(module, &module_ktype, &module_uevent_ops);
694 int module_sysfs_initialized;
696 static struct kobj_type module_ktype = {
697 .sysfs_ops = &module_sysfs_ops,
701 * param_sysfs_init - wrapper for built-in params support
703 static int __init param_sysfs_init(void)
707 ret = subsystem_register(&module_subsys);
709 printk(KERN_WARNING "%s (%d): subsystem_register error: %d\n",
710 __FILE__, __LINE__, ret);
713 module_sysfs_initialized = 1;
715 param_sysfs_builtin();
719 subsys_initcall(param_sysfs_init);
723 static struct sysfs_ops module_sysfs_ops = {
730 EXPORT_SYMBOL(param_set_byte);
731 EXPORT_SYMBOL(param_get_byte);
732 EXPORT_SYMBOL(param_set_short);
733 EXPORT_SYMBOL(param_get_short);
734 EXPORT_SYMBOL(param_set_ushort);
735 EXPORT_SYMBOL(param_get_ushort);
736 EXPORT_SYMBOL(param_set_int);
737 EXPORT_SYMBOL(param_get_int);
738 EXPORT_SYMBOL(param_set_uint);
739 EXPORT_SYMBOL(param_get_uint);
740 EXPORT_SYMBOL(param_set_long);
741 EXPORT_SYMBOL(param_get_long);
742 EXPORT_SYMBOL(param_set_ulong);
743 EXPORT_SYMBOL(param_get_ulong);
744 EXPORT_SYMBOL(param_set_charp);
745 EXPORT_SYMBOL(param_get_charp);
746 EXPORT_SYMBOL(param_set_bool);
747 EXPORT_SYMBOL(param_get_bool);
748 EXPORT_SYMBOL(param_set_invbool);
749 EXPORT_SYMBOL(param_get_invbool);
750 EXPORT_SYMBOL(param_array_set);
751 EXPORT_SYMBOL(param_array_get);
752 EXPORT_SYMBOL(param_set_copystring);
753 EXPORT_SYMBOL(param_get_string);