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 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)
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 if (kp->flags & KPARAM_KMALLOCED)
221 kfree(*(char **)kp->arg);
223 /* This is a hack. We can't need to strdup in early boot, and we
224 * don't need to; this mangled commandline is preserved. */
225 if (slab_is_available()) {
226 kp->flags |= KPARAM_KMALLOCED;
227 *(char **)kp->arg = kstrdup(val, GFP_KERNEL);
231 *(const char **)kp->arg = val;
236 int param_get_charp(char *buffer, struct kernel_param *kp)
238 return sprintf(buffer, "%s", *((char **)kp->arg));
241 /* Actually could be a bool or an int, for historical reasons. */
242 int param_set_bool(const char *val, struct kernel_param *kp)
246 /* No equals means "set"... */
249 /* One of =[yYnN01] */
251 case 'y': case 'Y': case '1':
254 case 'n': case 'N': case '0':
261 if (kp->flags & KPARAM_ISBOOL)
262 *(bool *)kp->arg = v;
268 int param_get_bool(char *buffer, struct kernel_param *kp)
271 if (kp->flags & KPARAM_ISBOOL)
272 val = *(bool *)kp->arg;
274 val = *(int *)kp->arg;
276 /* Y and N chosen as being relatively non-coder friendly */
277 return sprintf(buffer, "%c", val ? 'Y' : 'N');
280 /* This one must be bool. */
281 int param_set_invbool(const char *val, struct kernel_param *kp)
285 struct kernel_param dummy;
287 dummy.arg = &boolval;
288 dummy.flags = KPARAM_ISBOOL;
289 ret = param_set_bool(val, &dummy);
291 *(bool *)kp->arg = !boolval;
295 int param_get_invbool(char *buffer, struct kernel_param *kp)
297 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
300 /* We break the rule and mangle the string. */
301 static int param_array(const char *name,
303 unsigned int min, unsigned int max,
304 void *elem, int elemsize,
305 int (*set)(const char *, struct kernel_param *kp),
309 struct kernel_param kp;
312 /* Get the name right for errors. */
316 /* No equals sign? */
318 printk(KERN_ERR "%s: expects arguments\n", name);
323 /* We expect a comma-separated list of values. */
328 printk(KERN_ERR "%s: can only take %i arguments\n",
332 len = strcspn(val, ",");
334 /* nul-terminate and parse */
336 ((char *)val)[len] = '\0';
344 } while (save == ',');
347 printk(KERN_ERR "%s: needs at least %i arguments\n",
354 int param_array_set(const char *val, struct kernel_param *kp)
356 const struct kparam_array *arr = kp->arr;
357 unsigned int temp_num;
359 return param_array(kp->name, val, 1, arr->max, arr->elem,
360 arr->elemsize, arr->set, arr->num ?: &temp_num);
363 int param_array_get(char *buffer, struct kernel_param *kp)
366 const struct kparam_array *arr = kp->arr;
367 struct kernel_param p;
370 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
373 p.arg = arr->elem + arr->elemsize * i;
374 ret = arr->get(buffer + off, &p);
383 int param_set_copystring(const char *val, struct kernel_param *kp)
385 const struct kparam_string *kps = kp->str;
388 printk(KERN_ERR "%s: missing param set value\n", kp->name);
391 if (strlen(val)+1 > kps->maxlen) {
392 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
393 kp->name, kps->maxlen-1);
396 strcpy(kps->string, val);
400 int param_get_string(char *buffer, struct kernel_param *kp)
402 const struct kparam_string *kps = kp->str;
403 return strlcpy(buffer, kps->string, kps->maxlen);
406 /* sysfs output in /sys/modules/XYZ/parameters/ */
407 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
408 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
410 extern struct kernel_param __start___param[], __stop___param[];
412 struct param_attribute
414 struct module_attribute mattr;
415 struct kernel_param *param;
418 struct module_param_attrs
421 struct attribute_group grp;
422 struct param_attribute attrs[0];
426 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
428 static ssize_t param_attr_show(struct module_attribute *mattr,
429 struct module *mod, char *buf)
432 struct param_attribute *attribute = to_param_attr(mattr);
434 if (!attribute->param->get)
437 count = attribute->param->get(buf, attribute->param);
445 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
446 static ssize_t param_attr_store(struct module_attribute *mattr,
447 struct module *owner,
448 const char *buf, size_t len)
451 struct param_attribute *attribute = to_param_attr(mattr);
453 if (!attribute->param->set)
456 err = attribute->param->set(buf, attribute->param);
463 #ifdef CONFIG_MODULES
466 #define __modinit __init
471 * add_sysfs_param - add a parameter to sysfs
472 * @mk: struct module_kobject
473 * @kparam: the actual parameter definition to add to sysfs
474 * @name: name of parameter
476 * Create a kobject if for a (per-module) parameter if mp NULL, and
477 * create file in sysfs. Returns an error on out of memory. Always cleans up
478 * if there's an error.
480 static __modinit int add_sysfs_param(struct module_kobject *mk,
481 struct kernel_param *kp,
484 struct module_param_attrs *new;
485 struct attribute **attrs;
488 /* We don't bother calling this with invisible parameters. */
496 attrs = mk->mp->grp.attrs;
500 new = krealloc(mk->mp,
501 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
508 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
514 /* Sysfs wants everything zeroed. */
515 memset(new, 0, sizeof(*new));
516 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
517 memset(&attrs[num], 0, sizeof(attrs[num]));
518 new->grp.name = "parameters";
519 new->grp.attrs = attrs;
521 /* Tack new one on the end. */
522 new->attrs[num].param = kp;
523 new->attrs[num].mattr.show = param_attr_show;
524 new->attrs[num].mattr.store = param_attr_store;
525 new->attrs[num].mattr.attr.name = (char *)name;
526 new->attrs[num].mattr.attr.mode = kp->perm;
529 /* Fix up all the pointers, since krealloc can move us */
530 for (num = 0; num < new->num; num++)
531 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
532 new->grp.attrs[num] = NULL;
544 #ifdef CONFIG_MODULES
545 static void free_module_param_attrs(struct module_kobject *mk)
547 kfree(mk->mp->grp.attrs);
553 * module_param_sysfs_setup - setup sysfs support for one module
555 * @kparam: module parameters (array)
556 * @num_params: number of module parameters
558 * Adds sysfs entries for module parameters under
559 * /sys/module/[mod->name]/parameters/
561 int module_param_sysfs_setup(struct module *mod,
562 struct kernel_param *kparam,
563 unsigned int num_params)
568 for (i = 0; i < num_params; i++) {
569 if (kparam[i].perm == 0)
571 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
580 /* Create the param group. */
581 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
583 free_module_param_attrs(&mod->mkobj);
588 * module_param_sysfs_remove - remove sysfs support for one module
591 * Remove sysfs entries for module parameters and the corresponding
594 void module_param_sysfs_remove(struct module *mod)
597 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
598 /* We are positive that no one is using any param
599 * attrs at this point. Deallocate immediately. */
600 free_module_param_attrs(&mod->mkobj);
605 void destroy_params(const struct kernel_param *params, unsigned num)
609 for (i = 0; i < num; i++)
610 if (params[i].flags & KPARAM_KMALLOCED)
611 kfree(*(char **)params[i].arg);
614 static void __init kernel_add_sysfs_param(const char *name,
615 struct kernel_param *kparam,
616 unsigned int name_skip)
618 struct module_kobject *mk;
619 struct kobject *kobj;
622 kobj = kset_find_obj(module_kset, name);
624 /* We already have one. Remove params so we can add more. */
625 mk = to_module_kobject(kobj);
626 /* We need to remove it before adding parameters. */
627 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
629 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
632 mk->mod = THIS_MODULE;
633 mk->kobj.kset = module_kset;
634 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
637 kobject_put(&mk->kobj);
638 printk(KERN_ERR "Module '%s' failed add to sysfs, "
639 "error number %d\n", name, err);
640 printk(KERN_ERR "The system will be unstable now.\n");
643 /* So that exit path is even. */
644 kobject_get(&mk->kobj);
647 /* These should not fail at boot. */
648 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
650 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
652 kobject_uevent(&mk->kobj, KOBJ_ADD);
653 kobject_put(&mk->kobj);
657 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
659 * Add module_parameters to sysfs for "modules" built into the kernel.
661 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
662 * "parameter" name is stored behind a dot in kernel_param->name. So,
663 * extract the "module" name for all built-in kernel_param-eters,
664 * and for all who have the same, call kernel_add_sysfs_param.
666 static void __init param_sysfs_builtin(void)
668 struct kernel_param *kp;
669 unsigned int name_len;
670 char modname[MODULE_NAME_LEN];
672 for (kp = __start___param; kp < __stop___param; kp++) {
678 dot = strchr(kp->name, '.');
680 /* This happens for core_param() */
681 strcpy(modname, "kernel");
684 name_len = dot - kp->name + 1;
685 strlcpy(modname, kp->name, name_len);
687 kernel_add_sysfs_param(modname, kp, name_len);
692 /* module-related sysfs stuff */
694 static ssize_t module_attr_show(struct kobject *kobj,
695 struct attribute *attr,
698 struct module_attribute *attribute;
699 struct module_kobject *mk;
702 attribute = to_module_attr(attr);
703 mk = to_module_kobject(kobj);
705 if (!attribute->show)
708 ret = attribute->show(attribute, mk->mod, buf);
713 static ssize_t module_attr_store(struct kobject *kobj,
714 struct attribute *attr,
715 const char *buf, size_t len)
717 struct module_attribute *attribute;
718 struct module_kobject *mk;
721 attribute = to_module_attr(attr);
722 mk = to_module_kobject(kobj);
724 if (!attribute->store)
727 ret = attribute->store(attribute, mk->mod, buf, len);
732 static struct sysfs_ops module_sysfs_ops = {
733 .show = module_attr_show,
734 .store = module_attr_store,
737 static int uevent_filter(struct kset *kset, struct kobject *kobj)
739 struct kobj_type *ktype = get_ktype(kobj);
741 if (ktype == &module_ktype)
746 static struct kset_uevent_ops module_uevent_ops = {
747 .filter = uevent_filter,
750 struct kset *module_kset;
751 int module_sysfs_initialized;
753 struct kobj_type module_ktype = {
754 .sysfs_ops = &module_sysfs_ops,
758 * param_sysfs_init - wrapper for built-in params support
760 static int __init param_sysfs_init(void)
762 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
764 printk(KERN_WARNING "%s (%d): error creating kset\n",
768 module_sysfs_initialized = 1;
770 param_sysfs_builtin();
774 subsys_initcall(param_sysfs_init);
776 #endif /* CONFIG_SYSFS */
778 EXPORT_SYMBOL(param_set_byte);
779 EXPORT_SYMBOL(param_get_byte);
780 EXPORT_SYMBOL(param_set_short);
781 EXPORT_SYMBOL(param_get_short);
782 EXPORT_SYMBOL(param_set_ushort);
783 EXPORT_SYMBOL(param_get_ushort);
784 EXPORT_SYMBOL(param_set_int);
785 EXPORT_SYMBOL(param_get_int);
786 EXPORT_SYMBOL(param_set_uint);
787 EXPORT_SYMBOL(param_get_uint);
788 EXPORT_SYMBOL(param_set_long);
789 EXPORT_SYMBOL(param_get_long);
790 EXPORT_SYMBOL(param_set_ulong);
791 EXPORT_SYMBOL(param_get_ulong);
792 EXPORT_SYMBOL(param_set_charp);
793 EXPORT_SYMBOL(param_get_charp);
794 EXPORT_SYMBOL(param_set_bool);
795 EXPORT_SYMBOL(param_get_bool);
796 EXPORT_SYMBOL(param_set_invbool);
797 EXPORT_SYMBOL(param_get_invbool);
798 EXPORT_SYMBOL(param_array_set);
799 EXPORT_SYMBOL(param_array_get);
800 EXPORT_SYMBOL(param_set_copystring);
801 EXPORT_SYMBOL(param_get_string);