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/config.h>
19 #include <linux/moduleparam.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/errno.h>
23 #include <linux/module.h>
24 #include <linux/device.h>
25 #include <linux/err.h>
30 #define DEBUGP(fmt, a...)
33 static inline int 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;
83 /* Chew any extra spaces */
84 while (*args == ' ') args++;
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] == '"')
127 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
128 int parse_args(const char *name,
130 struct kernel_param *params,
132 int (*unknown)(char *param, char *val))
136 DEBUGP("Parsing ARGS: %s\n", args);
141 args = next_arg(args, ¶m, &val);
142 ret = parse_one(param, val, params, num, unknown);
145 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
150 "%s: `%s' too large for parameter `%s'\n",
151 name, val ?: "", param);
157 "%s: `%s' invalid for parameter `%s'\n",
158 name, val ?: "", param);
167 /* Lazy bastard, eh? */
168 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
169 int param_set_##name(const char *val, struct kernel_param *kp) \
174 if (!val) return -EINVAL; \
175 l = strtolfn(val, &endp, 0); \
176 if (endp == val || ((type)l != l)) \
178 *((type *)kp->arg) = l; \
181 int param_get_##name(char *buffer, struct kernel_param *kp) \
183 return sprintf(buffer, format, *((type *)kp->arg)); \
186 STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, simple_strtoul);
187 STANDARD_PARAM_DEF(short, short, "%hi", long, simple_strtol);
188 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, simple_strtoul);
189 STANDARD_PARAM_DEF(int, int, "%i", long, simple_strtol);
190 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, simple_strtoul);
191 STANDARD_PARAM_DEF(long, long, "%li", long, simple_strtol);
192 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, simple_strtoul);
194 int param_set_charp(const char *val, struct kernel_param *kp)
197 printk(KERN_ERR "%s: string parameter expected\n",
202 if (strlen(val) > 1024) {
203 printk(KERN_ERR "%s: string parameter too long\n",
208 *(char **)kp->arg = (char *)val;
212 int param_get_charp(char *buffer, struct kernel_param *kp)
214 return sprintf(buffer, "%s", *((char **)kp->arg));
217 int param_set_bool(const char *val, struct kernel_param *kp)
219 /* No equals means "set"... */
222 /* One of =[yYnN01] */
224 case 'y': case 'Y': case '1':
227 case 'n': case 'N': case '0':
234 int param_get_bool(char *buffer, struct kernel_param *kp)
236 /* Y and N chosen as being relatively non-coder friendly */
237 return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'Y' : 'N');
240 int param_set_invbool(const char *val, struct kernel_param *kp)
243 struct kernel_param dummy = { .arg = &boolval };
245 ret = param_set_bool(val, &dummy);
247 *(int *)kp->arg = !boolval;
251 int param_get_invbool(char *buffer, struct kernel_param *kp)
254 struct kernel_param dummy = { .arg = &val };
256 val = !*(int *)kp->arg;
257 return param_get_bool(buffer, &dummy);
260 /* We cheat here and temporarily mangle the string. */
261 int param_array(const char *name,
263 unsigned int min, unsigned int max,
264 void *elem, int elemsize,
265 int (*set)(const char *, struct kernel_param *kp),
269 struct kernel_param kp;
272 /* Get the name right for errors. */
276 /* No equals sign? */
278 printk(KERN_ERR "%s: expects arguments\n", name);
283 /* We expect a comma-separated list of values. */
288 printk(KERN_ERR "%s: can only take %i arguments\n",
292 len = strcspn(val, ",");
294 /* nul-terminate and parse */
296 ((char *)val)[len] = '\0';
304 } while (save == ',');
307 printk(KERN_ERR "%s: needs at least %i arguments\n",
314 int param_array_set(const char *val, struct kernel_param *kp)
316 struct kparam_array *arr = kp->arg;
317 unsigned int temp_num;
319 return param_array(kp->name, val, 1, arr->max, arr->elem,
320 arr->elemsize, arr->set, arr->num ?: &temp_num);
323 int param_array_get(char *buffer, struct kernel_param *kp)
326 struct kparam_array *arr = kp->arg;
327 struct kernel_param p;
330 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
333 p.arg = arr->elem + arr->elemsize * i;
334 ret = arr->get(buffer + off, &p);
343 int param_set_copystring(const char *val, struct kernel_param *kp)
345 struct kparam_string *kps = kp->arg;
347 if (strlen(val)+1 > kps->maxlen) {
348 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
349 kp->name, kps->maxlen-1);
352 strcpy(kps->string, val);
356 int param_get_string(char *buffer, struct kernel_param *kp)
358 struct kparam_string *kps = kp->arg;
359 return strlcpy(buffer, kps->string, kps->maxlen);
362 /* sysfs output in /sys/modules/XYZ/parameters/ */
364 extern struct kernel_param __start___param[], __stop___param[];
366 #define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
368 struct param_attribute
370 struct module_attribute mattr;
371 struct kernel_param *param;
374 struct module_param_attrs
376 struct attribute_group grp;
377 struct param_attribute attrs[0];
380 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
382 static ssize_t param_attr_show(struct module_attribute *mattr,
383 struct module *mod, char *buf)
386 struct param_attribute *attribute = to_param_attr(mattr);
388 if (!attribute->param->get)
391 count = attribute->param->get(buf, attribute->param);
399 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
400 static ssize_t param_attr_store(struct module_attribute *mattr,
401 struct module *owner,
402 const char *buf, size_t len)
405 struct param_attribute *attribute = to_param_attr(mattr);
407 if (!attribute->param->set)
410 err = attribute->param->set(buf, attribute->param);
416 #ifdef CONFIG_MODULES
419 #define __modinit __init
423 * param_sysfs_setup - setup sysfs support for one module or KBUILD_MODNAME
424 * @mk: struct module_kobject (contains parent kobject)
425 * @kparam: array of struct kernel_param, the actual parameter definitions
426 * @num_params: number of entries in array
427 * @name_skip: offset where the parameter name start in kparam[].name. Needed for built-in "modules"
429 * Create a kobject for a (per-module) group of parameters, and create files
430 * in sysfs. A pointer to the param_kobject is returned on success,
431 * NULL if there's no parameter to export, or other ERR_PTR(err).
433 static __modinit struct module_param_attrs *
434 param_sysfs_setup(struct module_kobject *mk,
435 struct kernel_param *kparam,
436 unsigned int num_params,
437 unsigned int name_skip)
439 struct module_param_attrs *mp;
440 unsigned int valid_attrs = 0;
441 unsigned int i, size[2];
442 struct param_attribute *pattr;
443 struct attribute **gattr;
446 for (i=0; i<num_params; i++) {
454 size[0] = ALIGN(sizeof(*mp) +
455 valid_attrs * sizeof(mp->attrs[0]),
456 sizeof(mp->grp.attrs[0]));
457 size[1] = (valid_attrs + 1) * sizeof(mp->grp.attrs[0]);
459 mp = kmalloc(size[0] + size[1], GFP_KERNEL);
461 return ERR_PTR(-ENOMEM);
463 mp->grp.name = "parameters";
464 mp->grp.attrs = (void *)mp + size[0];
466 pattr = &mp->attrs[0];
467 gattr = &mp->grp.attrs[0];
468 for (i = 0; i < num_params; i++) {
469 struct kernel_param *kp = &kparam[i];
472 pattr->mattr.show = param_attr_show;
473 pattr->mattr.store = param_attr_store;
474 pattr->mattr.attr.name = (char *)&kp->name[name_skip];
475 pattr->mattr.attr.owner = mk->mod;
476 pattr->mattr.attr.mode = kp->perm;
477 *(gattr++) = &(pattr++)->mattr.attr;
482 if ((err = sysfs_create_group(&mk->kobj, &mp->grp))) {
490 #ifdef CONFIG_MODULES
493 * module_param_sysfs_setup - setup sysfs support for one module
495 * @kparam: module parameters (array)
496 * @num_params: number of module parameters
498 * Adds sysfs entries for module parameters, and creates a link from
499 * /sys/module/[mod->name]/parameters to /sys/parameters/[mod->name]/
501 int module_param_sysfs_setup(struct module *mod,
502 struct kernel_param *kparam,
503 unsigned int num_params)
505 struct module_param_attrs *mp;
507 mp = param_sysfs_setup(&mod->mkobj, kparam, num_params, 0);
511 mod->param_attrs = mp;
516 * module_param_sysfs_remove - remove sysfs support for one module
519 * Remove sysfs entries for module parameters and the corresponding
522 void module_param_sysfs_remove(struct module *mod)
524 if (mod->param_attrs) {
525 sysfs_remove_group(&mod->mkobj.kobj,
526 &mod->param_attrs->grp);
527 /* We are positive that no one is using any param
528 * attrs at this point. Deallocate immediately. */
529 kfree(mod->param_attrs);
530 mod->param_attrs = NULL;
536 * kernel_param_sysfs_setup - wrapper for built-in params support
538 static void __init kernel_param_sysfs_setup(const char *name,
539 struct kernel_param *kparam,
540 unsigned int num_params,
541 unsigned int name_skip)
543 struct module_kobject *mk;
545 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
548 mk->mod = THIS_MODULE;
549 kobj_set_kset_s(mk, module_subsys);
550 kobject_set_name(&mk->kobj, name);
551 kobject_register(&mk->kobj);
553 /* no need to keep the kobject if no parameter is exported */
554 if (!param_sysfs_setup(mk, kparam, num_params, name_skip)) {
555 kobject_unregister(&mk->kobj);
561 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
563 * Add module_parameters to sysfs for "modules" built into the kernel.
565 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
566 * "parameter" name is stored behind a dot in kernel_param->name. So,
567 * extract the "module" name for all built-in kernel_param-eters,
568 * and for all who have the same, call kernel_param_sysfs_setup.
570 static void __init param_sysfs_builtin(void)
572 struct kernel_param *kp, *kp_begin = NULL;
573 unsigned int i, name_len, count = 0;
574 char modname[MAX_KBUILD_MODNAME + 1] = "";
576 for (i=0; i < __stop___param - __start___param; i++) {
579 kp = &__start___param[i];
581 /* We do not handle args without periods. */
582 dot = memchr(kp->name, '.', MAX_KBUILD_MODNAME);
584 DEBUGP("couldn't find period in %s\n", kp->name);
587 name_len = dot - kp->name;
589 /* new kbuild_modname? */
590 if (strlen(modname) != name_len
591 || strncmp(modname, kp->name, name_len) != 0) {
592 /* add a new kobject for previous kernel_params. */
594 kernel_param_sysfs_setup(modname,
599 strncpy(modname, kp->name, name_len);
600 modname[name_len] = '\0';
607 /* last kernel_params need to be registered as well */
609 kernel_param_sysfs_setup(modname, kp_begin, count,
614 /* module-related sysfs stuff */
615 #ifdef CONFIG_MODULES
617 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
618 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
620 static ssize_t module_attr_show(struct kobject *kobj,
621 struct attribute *attr,
624 struct module_attribute *attribute;
625 struct module_kobject *mk;
628 attribute = to_module_attr(attr);
629 mk = to_module_kobject(kobj);
631 if (!attribute->show)
634 if (!try_module_get(mk->mod))
637 ret = attribute->show(attribute, mk->mod, buf);
644 static ssize_t module_attr_store(struct kobject *kobj,
645 struct attribute *attr,
646 const char *buf, size_t len)
648 struct module_attribute *attribute;
649 struct module_kobject *mk;
652 attribute = to_module_attr(attr);
653 mk = to_module_kobject(kobj);
655 if (!attribute->store)
658 if (!try_module_get(mk->mod))
661 ret = attribute->store(attribute, mk->mod, buf, len);
668 static struct sysfs_ops module_sysfs_ops = {
669 .show = module_attr_show,
670 .store = module_attr_store,
674 static struct sysfs_ops module_sysfs_ops = {
680 static struct kobj_type module_ktype = {
681 .sysfs_ops = &module_sysfs_ops,
684 decl_subsys(module, &module_ktype, NULL);
687 * param_sysfs_init - wrapper for built-in params support
689 static int __init param_sysfs_init(void)
691 subsystem_register(&module_subsys);
693 param_sysfs_builtin();
697 __initcall(param_sysfs_init);
699 EXPORT_SYMBOL(param_set_byte);
700 EXPORT_SYMBOL(param_get_byte);
701 EXPORT_SYMBOL(param_set_short);
702 EXPORT_SYMBOL(param_get_short);
703 EXPORT_SYMBOL(param_set_ushort);
704 EXPORT_SYMBOL(param_get_ushort);
705 EXPORT_SYMBOL(param_set_int);
706 EXPORT_SYMBOL(param_get_int);
707 EXPORT_SYMBOL(param_set_uint);
708 EXPORT_SYMBOL(param_get_uint);
709 EXPORT_SYMBOL(param_set_long);
710 EXPORT_SYMBOL(param_get_long);
711 EXPORT_SYMBOL(param_set_ulong);
712 EXPORT_SYMBOL(param_get_ulong);
713 EXPORT_SYMBOL(param_set_charp);
714 EXPORT_SYMBOL(param_get_charp);
715 EXPORT_SYMBOL(param_set_bool);
716 EXPORT_SYMBOL(param_get_bool);
717 EXPORT_SYMBOL(param_set_invbool);
718 EXPORT_SYMBOL(param_get_invbool);
719 EXPORT_SYMBOL(param_array_set);
720 EXPORT_SYMBOL(param_array_get);
721 EXPORT_SYMBOL(param_set_copystring);
722 EXPORT_SYMBOL(param_get_string);