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
);