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>
27 #include <linux/string.h>
32 #define DEBUGP(fmt, a...)
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 (isspace(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. */
126 return skip_spaces(next);
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 */
141 args = skip_spaces(args);
145 int irq_was_disabled;
147 args = next_arg(args, ¶m, &val);
148 irq_was_disabled = irqs_disabled();
149 ret = parse_one(param, val, params, num, unknown);
150 if (irq_was_disabled && !irqs_disabled()) {
151 printk(KERN_WARNING "parse_args(): option '%s' enabled "
156 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
161 "%s: `%s' too large for parameter `%s'\n",
162 name, val ?: "", param);
168 "%s: `%s' invalid for parameter `%s'\n",
169 name, val ?: "", param);
178 /* Lazy bastard, eh? */
179 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
180 int param_set_##name(const char *val, struct kernel_param *kp) \
185 if (!val) return -EINVAL; \
186 ret = strtolfn(val, 0, &l); \
187 if (ret == -EINVAL || ((type)l != l)) \
189 *((type *)kp->arg) = l; \
192 int param_get_##name(char *buffer, struct kernel_param *kp) \
194 return sprintf(buffer, format, *((type *)kp->arg)); \
197 STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
198 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
199 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
200 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
201 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
202 STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
203 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
205 int param_set_charp(const char *val, struct kernel_param *kp)
208 printk(KERN_ERR "%s: string parameter expected\n",
213 if (strlen(val) > 1024) {
214 printk(KERN_ERR "%s: string parameter too long\n",
219 /* This is a hack. We can't need to strdup in early boot, and we
220 * don't need to; this mangled commandline is preserved. */
221 if (slab_is_available()) {
222 *(char **)kp->arg = kstrdup(val, GFP_KERNEL);
223 if (!*(char **)kp->arg)
226 *(const char **)kp->arg = val;
231 int param_get_charp(char *buffer, struct kernel_param *kp)
233 return sprintf(buffer, "%s", *((char **)kp->arg));
236 /* Actually could be a bool or an int, for historical reasons. */
237 int param_set_bool(const char *val, struct kernel_param *kp)
241 /* No equals means "set"... */
244 /* One of =[yYnN01] */
246 case 'y': case 'Y': case '1':
249 case 'n': case 'N': case '0':
256 if (kp->flags & KPARAM_ISBOOL)
257 *(bool *)kp->arg = v;
263 int param_get_bool(char *buffer, struct kernel_param *kp)
266 if (kp->flags & KPARAM_ISBOOL)
267 val = *(bool *)kp->arg;
269 val = *(int *)kp->arg;
271 /* Y and N chosen as being relatively non-coder friendly */
272 return sprintf(buffer, "%c", val ? 'Y' : 'N');
275 /* This one must be bool. */
276 int param_set_invbool(const char *val, struct kernel_param *kp)
280 struct kernel_param dummy;
282 dummy.arg = &boolval;
283 dummy.flags = KPARAM_ISBOOL;
284 ret = param_set_bool(val, &dummy);
286 *(bool *)kp->arg = !boolval;
290 int param_get_invbool(char *buffer, struct kernel_param *kp)
292 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
295 /* We break the rule and mangle the string. */
296 static int param_array(const char *name,
298 unsigned int min, unsigned int max,
299 void *elem, int elemsize,
300 int (*set)(const char *, struct kernel_param *kp),
305 struct kernel_param kp;
308 /* Get the name right for errors. */
313 /* No equals sign? */
315 printk(KERN_ERR "%s: expects arguments\n", name);
320 /* We expect a comma-separated list of values. */
325 printk(KERN_ERR "%s: can only take %i arguments\n",
329 len = strcspn(val, ",");
331 /* nul-terminate and parse */
333 ((char *)val)[len] = '\0';
341 } while (save == ',');
344 printk(KERN_ERR "%s: needs at least %i arguments\n",
351 int param_array_set(const char *val, struct kernel_param *kp)
353 const struct kparam_array *arr = kp->arr;
354 unsigned int temp_num;
356 return param_array(kp->name, val, 1, arr->max, arr->elem,
357 arr->elemsize, arr->set, kp->flags,
358 arr->num ?: &temp_num);
361 int param_array_get(char *buffer, struct kernel_param *kp)
364 const struct kparam_array *arr = kp->arr;
365 struct kernel_param p;
368 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
371 p.arg = arr->elem + arr->elemsize * i;
372 ret = arr->get(buffer + off, &p);
381 int param_set_copystring(const char *val, struct kernel_param *kp)
383 const struct kparam_string *kps = kp->str;
386 printk(KERN_ERR "%s: missing param set value\n", kp->name);
389 if (strlen(val)+1 > kps->maxlen) {
390 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
391 kp->name, kps->maxlen-1);
394 strcpy(kps->string, val);
398 int param_get_string(char *buffer, struct kernel_param *kp)
400 const struct kparam_string *kps = kp->str;
401 return strlcpy(buffer, kps->string, kps->maxlen);
404 /* sysfs output in /sys/modules/XYZ/parameters/ */
405 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
406 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
408 extern struct kernel_param __start___param[], __stop___param[];
410 struct param_attribute
412 struct module_attribute mattr;
413 struct kernel_param *param;
416 struct module_param_attrs
419 struct attribute_group grp;
420 struct param_attribute attrs[0];
424 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
426 static ssize_t param_attr_show(struct module_attribute *mattr,
427 struct module *mod, char *buf)
430 struct param_attribute *attribute = to_param_attr(mattr);
432 if (!attribute->param->get)
435 count = attribute->param->get(buf, attribute->param);
443 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
444 static ssize_t param_attr_store(struct module_attribute *mattr,
445 struct module *owner,
446 const char *buf, size_t len)
449 struct param_attribute *attribute = to_param_attr(mattr);
451 if (!attribute->param->set)
454 err = attribute->param->set(buf, attribute->param);
461 #ifdef CONFIG_MODULES
464 #define __modinit __init
469 * add_sysfs_param - add a parameter to sysfs
470 * @mk: struct module_kobject
471 * @kparam: the actual parameter definition to add to sysfs
472 * @name: name of parameter
474 * Create a kobject if for a (per-module) parameter if mp NULL, and
475 * create file in sysfs. Returns an error on out of memory. Always cleans up
476 * if there's an error.
478 static __modinit int add_sysfs_param(struct module_kobject *mk,
479 struct kernel_param *kp,
482 struct module_param_attrs *new;
483 struct attribute **attrs;
486 /* We don't bother calling this with invisible parameters. */
494 attrs = mk->mp->grp.attrs;
498 new = krealloc(mk->mp,
499 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
506 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
512 /* Sysfs wants everything zeroed. */
513 memset(new, 0, sizeof(*new));
514 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
515 memset(&attrs[num], 0, sizeof(attrs[num]));
516 new->grp.name = "parameters";
517 new->grp.attrs = attrs;
519 /* Tack new one on the end. */
520 new->attrs[num].param = kp;
521 new->attrs[num].mattr.show = param_attr_show;
522 new->attrs[num].mattr.store = param_attr_store;
523 new->attrs[num].mattr.attr.name = (char *)name;
524 new->attrs[num].mattr.attr.mode = kp->perm;
527 /* Fix up all the pointers, since krealloc can move us */
528 for (num = 0; num < new->num; num++)
529 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
530 new->grp.attrs[num] = NULL;
542 #ifdef CONFIG_MODULES
543 static void free_module_param_attrs(struct module_kobject *mk)
545 kfree(mk->mp->grp.attrs);
551 * module_param_sysfs_setup - setup sysfs support for one module
553 * @kparam: module parameters (array)
554 * @num_params: number of module parameters
556 * Adds sysfs entries for module parameters under
557 * /sys/module/[mod->name]/parameters/
559 int module_param_sysfs_setup(struct module *mod,
560 struct kernel_param *kparam,
561 unsigned int num_params)
566 for (i = 0; i < num_params; i++) {
567 if (kparam[i].perm == 0)
569 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
578 /* Create the param group. */
579 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
581 free_module_param_attrs(&mod->mkobj);
586 * module_param_sysfs_remove - remove sysfs support for one module
589 * Remove sysfs entries for module parameters and the corresponding
592 void module_param_sysfs_remove(struct module *mod)
595 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
596 /* We are positive that no one is using any param
597 * attrs at this point. Deallocate immediately. */
598 free_module_param_attrs(&mod->mkobj);
603 void destroy_params(const struct kernel_param *params, unsigned num)
605 /* FIXME: This should free kmalloced charp parameters. It doesn't. */
608 static void __init kernel_add_sysfs_param(const char *name,
609 struct kernel_param *kparam,
610 unsigned int name_skip)
612 struct module_kobject *mk;
613 struct kobject *kobj;
616 kobj = kset_find_obj(module_kset, name);
618 /* We already have one. Remove params so we can add more. */
619 mk = to_module_kobject(kobj);
620 /* We need to remove it before adding parameters. */
621 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
623 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
626 mk->mod = THIS_MODULE;
627 mk->kobj.kset = module_kset;
628 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
631 kobject_put(&mk->kobj);
632 printk(KERN_ERR "Module '%s' failed add to sysfs, "
633 "error number %d\n", name, err);
634 printk(KERN_ERR "The system will be unstable now.\n");
637 /* So that exit path is even. */
638 kobject_get(&mk->kobj);
641 /* These should not fail at boot. */
642 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
644 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
646 kobject_uevent(&mk->kobj, KOBJ_ADD);
647 kobject_put(&mk->kobj);
651 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
653 * Add module_parameters to sysfs for "modules" built into the kernel.
655 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
656 * "parameter" name is stored behind a dot in kernel_param->name. So,
657 * extract the "module" name for all built-in kernel_param-eters,
658 * and for all who have the same, call kernel_add_sysfs_param.
660 static void __init param_sysfs_builtin(void)
662 struct kernel_param *kp;
663 unsigned int name_len;
664 char modname[MODULE_NAME_LEN];
666 for (kp = __start___param; kp < __stop___param; kp++) {
672 dot = strchr(kp->name, '.');
674 /* This happens for core_param() */
675 strcpy(modname, "kernel");
678 name_len = dot - kp->name + 1;
679 strlcpy(modname, kp->name, name_len);
681 kernel_add_sysfs_param(modname, kp, name_len);
686 /* module-related sysfs stuff */
688 static ssize_t module_attr_show(struct kobject *kobj,
689 struct attribute *attr,
692 struct module_attribute *attribute;
693 struct module_kobject *mk;
696 attribute = to_module_attr(attr);
697 mk = to_module_kobject(kobj);
699 if (!attribute->show)
702 ret = attribute->show(attribute, mk->mod, buf);
707 static ssize_t module_attr_store(struct kobject *kobj,
708 struct attribute *attr,
709 const char *buf, size_t len)
711 struct module_attribute *attribute;
712 struct module_kobject *mk;
715 attribute = to_module_attr(attr);
716 mk = to_module_kobject(kobj);
718 if (!attribute->store)
721 ret = attribute->store(attribute, mk->mod, buf, len);
726 static struct sysfs_ops module_sysfs_ops = {
727 .show = module_attr_show,
728 .store = module_attr_store,
731 static int uevent_filter(struct kset *kset, struct kobject *kobj)
733 struct kobj_type *ktype = get_ktype(kobj);
735 if (ktype == &module_ktype)
740 static struct kset_uevent_ops module_uevent_ops = {
741 .filter = uevent_filter,
744 struct kset *module_kset;
745 int module_sysfs_initialized;
747 struct kobj_type module_ktype = {
748 .sysfs_ops = &module_sysfs_ops,
752 * param_sysfs_init - wrapper for built-in params support
754 static int __init param_sysfs_init(void)
756 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
758 printk(KERN_WARNING "%s (%d): error creating kset\n",
762 module_sysfs_initialized = 1;
764 param_sysfs_builtin();
768 subsys_initcall(param_sysfs_init);
770 #endif /* CONFIG_SYSFS */
772 EXPORT_SYMBOL(param_set_byte);
773 EXPORT_SYMBOL(param_get_byte);
774 EXPORT_SYMBOL(param_set_short);
775 EXPORT_SYMBOL(param_get_short);
776 EXPORT_SYMBOL(param_set_ushort);
777 EXPORT_SYMBOL(param_get_ushort);
778 EXPORT_SYMBOL(param_set_int);
779 EXPORT_SYMBOL(param_get_int);
780 EXPORT_SYMBOL(param_set_uint);
781 EXPORT_SYMBOL(param_get_uint);
782 EXPORT_SYMBOL(param_set_long);
783 EXPORT_SYMBOL(param_get_long);
784 EXPORT_SYMBOL(param_set_ulong);
785 EXPORT_SYMBOL(param_get_ulong);
786 EXPORT_SYMBOL(param_set_charp);
787 EXPORT_SYMBOL(param_get_charp);
788 EXPORT_SYMBOL(param_set_bool);
789 EXPORT_SYMBOL(param_get_bool);
790 EXPORT_SYMBOL(param_set_invbool);
791 EXPORT_SYMBOL(param_get_invbool);
792 EXPORT_SYMBOL(param_array_set);
793 EXPORT_SYMBOL(param_array_get);
794 EXPORT_SYMBOL(param_set_copystring);
795 EXPORT_SYMBOL(param_get_string);