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
;
257 dummy
.arg
= &boolval
;
258 ret
= param_set_bool(val
, &dummy
);
260 *(int *)kp
->arg
= !boolval
;
264 int param_get_invbool(char *buffer
, struct kernel_param
*kp
)
266 return sprintf(buffer
, "%c", (*(int *)kp
->arg
) ? 'N' : 'Y');
269 /* We break the rule and mangle the string. */
270 static int param_array(const char *name
,
272 unsigned int min
, unsigned int max
,
273 void *elem
, int elemsize
,
274 int (*set
)(const char *, struct kernel_param
*kp
),
278 struct kernel_param kp
;
281 /* Get the name right for errors. */
285 /* No equals sign? */
287 printk(KERN_ERR
"%s: expects arguments\n", name
);
292 /* We expect a comma-separated list of values. */
297 printk(KERN_ERR
"%s: can only take %i arguments\n",
301 len
= strcspn(val
, ",");
303 /* nul-terminate and parse */
305 ((char *)val
)[len
] = '\0';
313 } while (save
== ',');
316 printk(KERN_ERR
"%s: needs at least %i arguments\n",
323 int param_array_set(const char *val
, struct kernel_param
*kp
)
325 const struct kparam_array
*arr
= kp
->arr
;
326 unsigned int temp_num
;
328 return param_array(kp
->name
, val
, 1, arr
->max
, arr
->elem
,
329 arr
->elemsize
, arr
->set
, arr
->num
?: &temp_num
);
332 int param_array_get(char *buffer
, struct kernel_param
*kp
)
335 const struct kparam_array
*arr
= kp
->arr
;
336 struct kernel_param p
;
339 for (i
= off
= 0; i
< (arr
->num
? *arr
->num
: arr
->max
); i
++) {
342 p
.arg
= arr
->elem
+ arr
->elemsize
* i
;
343 ret
= arr
->get(buffer
+ off
, &p
);
352 int param_set_copystring(const char *val
, struct kernel_param
*kp
)
354 const struct kparam_string
*kps
= kp
->str
;
357 printk(KERN_ERR
"%s: missing param set value\n", kp
->name
);
360 if (strlen(val
)+1 > kps
->maxlen
) {
361 printk(KERN_ERR
"%s: string doesn't fit in %u chars.\n",
362 kp
->name
, kps
->maxlen
-1);
365 strcpy(kps
->string
, val
);
369 int param_get_string(char *buffer
, struct kernel_param
*kp
)
371 const struct kparam_string
*kps
= kp
->str
;
372 return strlcpy(buffer
, kps
->string
, kps
->maxlen
);
375 /* sysfs output in /sys/modules/XYZ/parameters/ */
377 extern struct kernel_param __start___param
[], __stop___param
[];
379 #define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
381 struct param_attribute
383 struct module_attribute mattr
;
384 struct kernel_param
*param
;
387 struct module_param_attrs
389 struct attribute_group grp
;
390 struct param_attribute attrs
[0];
394 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
396 static ssize_t
param_attr_show(struct module_attribute
*mattr
,
397 struct module
*mod
, char *buf
)
400 struct param_attribute
*attribute
= to_param_attr(mattr
);
402 if (!attribute
->param
->get
)
405 count
= attribute
->param
->get(buf
, attribute
->param
);
413 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
414 static ssize_t
param_attr_store(struct module_attribute
*mattr
,
415 struct module
*owner
,
416 const char *buf
, size_t len
)
419 struct param_attribute
*attribute
= to_param_attr(mattr
);
421 if (!attribute
->param
->set
)
424 err
= attribute
->param
->set(buf
, attribute
->param
);
431 #ifdef CONFIG_MODULES
434 #define __modinit __init
439 * param_sysfs_setup - setup sysfs support for one module or KBUILD_MODNAME
440 * @mk: struct module_kobject (contains parent kobject)
441 * @kparam: array of struct kernel_param, the actual parameter definitions
442 * @num_params: number of entries in array
443 * @name_skip: offset where the parameter name start in kparam[].name. Needed for built-in "modules"
445 * Create a kobject for a (per-module) group of parameters, and create files
446 * in sysfs. A pointer to the param_kobject is returned on success,
447 * NULL if there's no parameter to export, or other ERR_PTR(err).
449 static __modinit
struct module_param_attrs
*
450 param_sysfs_setup(struct module_kobject
*mk
,
451 struct kernel_param
*kparam
,
452 unsigned int num_params
,
453 unsigned int name_skip
)
455 struct module_param_attrs
*mp
;
456 unsigned int valid_attrs
= 0;
457 unsigned int i
, size
[2];
458 struct param_attribute
*pattr
;
459 struct attribute
**gattr
;
462 for (i
=0; i
<num_params
; i
++) {
470 size
[0] = ALIGN(sizeof(*mp
) +
471 valid_attrs
* sizeof(mp
->attrs
[0]),
472 sizeof(mp
->grp
.attrs
[0]));
473 size
[1] = (valid_attrs
+ 1) * sizeof(mp
->grp
.attrs
[0]);
475 mp
= kmalloc(size
[0] + size
[1], GFP_KERNEL
);
477 return ERR_PTR(-ENOMEM
);
479 mp
->grp
.name
= "parameters";
480 mp
->grp
.attrs
= (void *)mp
+ size
[0];
482 pattr
= &mp
->attrs
[0];
483 gattr
= &mp
->grp
.attrs
[0];
484 for (i
= 0; i
< num_params
; i
++) {
485 struct kernel_param
*kp
= &kparam
[i
];
488 pattr
->mattr
.show
= param_attr_show
;
489 pattr
->mattr
.store
= param_attr_store
;
490 pattr
->mattr
.attr
.name
= (char *)&kp
->name
[name_skip
];
491 pattr
->mattr
.attr
.mode
= kp
->perm
;
492 *(gattr
++) = &(pattr
++)->mattr
.attr
;
497 if ((err
= sysfs_create_group(&mk
->kobj
, &mp
->grp
))) {
504 #ifdef CONFIG_MODULES
506 * module_param_sysfs_setup - setup sysfs support for one module
508 * @kparam: module parameters (array)
509 * @num_params: number of module parameters
511 * Adds sysfs entries for module parameters, and creates a link from
512 * /sys/module/[mod->name]/parameters to /sys/parameters/[mod->name]/
514 int module_param_sysfs_setup(struct module
*mod
,
515 struct kernel_param
*kparam
,
516 unsigned int num_params
)
518 struct module_param_attrs
*mp
;
520 mp
= param_sysfs_setup(&mod
->mkobj
, kparam
, num_params
, 0);
524 mod
->param_attrs
= mp
;
529 * module_param_sysfs_remove - remove sysfs support for one module
532 * Remove sysfs entries for module parameters and the corresponding
535 void module_param_sysfs_remove(struct module
*mod
)
537 if (mod
->param_attrs
) {
538 sysfs_remove_group(&mod
->mkobj
.kobj
,
539 &mod
->param_attrs
->grp
);
540 /* We are positive that no one is using any param
541 * attrs at this point. Deallocate immediately. */
542 kfree(mod
->param_attrs
);
543 mod
->param_attrs
= NULL
;
549 * kernel_param_sysfs_setup - wrapper for built-in params support
551 static void __init
kernel_param_sysfs_setup(const char *name
,
552 struct kernel_param
*kparam
,
553 unsigned int num_params
,
554 unsigned int name_skip
)
556 struct module_kobject
*mk
;
559 mk
= kzalloc(sizeof(struct module_kobject
), GFP_KERNEL
);
562 mk
->mod
= THIS_MODULE
;
563 kobj_set_kset_s(mk
, module_subsys
);
564 kobject_set_name(&mk
->kobj
, name
);
565 kobject_init(&mk
->kobj
);
566 ret
= kobject_add(&mk
->kobj
);
568 printk(KERN_ERR
"Module '%s' failed to be added to sysfs, "
569 "error number %d\n", name
, ret
);
570 printk(KERN_ERR
"The system will be unstable now.\n");
573 param_sysfs_setup(mk
, kparam
, num_params
, name_skip
);
574 kobject_uevent(&mk
->kobj
, KOBJ_ADD
);
578 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
580 * Add module_parameters to sysfs for "modules" built into the kernel.
582 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
583 * "parameter" name is stored behind a dot in kernel_param->name. So,
584 * extract the "module" name for all built-in kernel_param-eters,
585 * and for all who have the same, call kernel_param_sysfs_setup.
587 static void __init
param_sysfs_builtin(void)
589 struct kernel_param
*kp
, *kp_begin
= NULL
;
590 unsigned int i
, name_len
, count
= 0;
591 char modname
[MAX_KBUILD_MODNAME
+ 1] = "";
593 for (i
=0; i
< __stop___param
- __start___param
; i
++) {
597 kp
= &__start___param
[i
];
598 kplen
= strlen(kp
->name
);
600 /* We do not handle args without periods. */
601 if (kplen
> MAX_KBUILD_MODNAME
) {
602 DEBUGP("kernel parameter name is too long: %s\n", kp
->name
);
605 dot
= memchr(kp
->name
, '.', kplen
);
607 DEBUGP("couldn't find period in %s\n", 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 struct kobj_type module_ktype
;
687 static int uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
689 struct kobj_type
*ktype
= get_ktype(kobj
);
691 if (ktype
== &module_ktype
)
696 static struct kset_uevent_ops module_uevent_ops
= {
697 .filter
= uevent_filter
,
700 decl_subsys(module
, &module_ktype
, &module_uevent_ops
);
701 int module_sysfs_initialized
;
703 static struct kobj_type module_ktype
= {
704 .sysfs_ops
= &module_sysfs_ops
,
708 * param_sysfs_init - wrapper for built-in params support
710 static int __init
param_sysfs_init(void)
714 ret
= subsystem_register(&module_subsys
);
716 printk(KERN_WARNING
"%s (%d): subsystem_register error: %d\n",
717 __FILE__
, __LINE__
, ret
);
720 module_sysfs_initialized
= 1;
722 param_sysfs_builtin();
726 subsys_initcall(param_sysfs_init
);
730 static struct sysfs_ops module_sysfs_ops
= {
737 EXPORT_SYMBOL(param_set_byte
);
738 EXPORT_SYMBOL(param_get_byte
);
739 EXPORT_SYMBOL(param_set_short
);
740 EXPORT_SYMBOL(param_get_short
);
741 EXPORT_SYMBOL(param_set_ushort
);
742 EXPORT_SYMBOL(param_get_ushort
);
743 EXPORT_SYMBOL(param_set_int
);
744 EXPORT_SYMBOL(param_get_int
);
745 EXPORT_SYMBOL(param_set_uint
);
746 EXPORT_SYMBOL(param_get_uint
);
747 EXPORT_SYMBOL(param_set_long
);
748 EXPORT_SYMBOL(param_get_long
);
749 EXPORT_SYMBOL(param_set_ulong
);
750 EXPORT_SYMBOL(param_get_ulong
);
751 EXPORT_SYMBOL(param_set_charp
);
752 EXPORT_SYMBOL(param_get_charp
);
753 EXPORT_SYMBOL(param_set_bool
);
754 EXPORT_SYMBOL(param_get_bool
);
755 EXPORT_SYMBOL(param_set_invbool
);
756 EXPORT_SYMBOL(param_get_invbool
);
757 EXPORT_SYMBOL(param_array_set
);
758 EXPORT_SYMBOL(param_array_get
);
759 EXPORT_SYMBOL(param_set_copystring
);
760 EXPORT_SYMBOL(param_get_string
);