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>
26 #include <linux/slab.h>
31 #define DEBUGP(fmt, a...)
34 static inline int dash2underscore(char c
)
41 static inline int parameq(const char *input
, const char *paramname
)
44 for (i
= 0; dash2underscore(input
[i
]) == paramname
[i
]; i
++)
50 static int parse_one(char *param
,
52 struct kernel_param
*params
,
54 int (*handle_unknown
)(char *param
, char *val
))
59 for (i
= 0; i
< num_params
; i
++) {
60 if (parameq(param
, params
[i
].name
)) {
61 DEBUGP("They are equal! Calling %p\n",
63 return params
[i
].set(val
, ¶ms
[i
]);
68 DEBUGP("Unknown argument: calling %p\n", handle_unknown
);
69 return handle_unknown(param
, val
);
72 DEBUGP("Unknown argument `%s'\n", param
);
76 /* You can use " around spaces, but can't escape ". */
77 /* Hyphens and underscores equivalent in parameter names. */
78 static char *next_arg(char *args
, char **param
, char **val
)
80 unsigned int i
, equals
= 0;
81 int in_quote
= 0, quoted
= 0;
90 for (i
= 0; args
[i
]; i
++) {
91 if (args
[i
] == ' ' && !in_quote
)
106 *val
= args
+ equals
+ 1;
108 /* Don't include quotes in value. */
111 if (args
[i
-1] == '"')
114 if (quoted
&& args
[i
-1] == '"')
124 /* Chew up trailing spaces. */
130 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
131 int parse_args(const char *name
,
133 struct kernel_param
*params
,
135 int (*unknown
)(char *param
, char *val
))
139 DEBUGP("Parsing ARGS: %s\n", args
);
141 /* Chew leading spaces */
148 args
= next_arg(args
, ¶m
, &val
);
149 ret
= parse_one(param
, val
, params
, num
, unknown
);
152 printk(KERN_ERR
"%s: Unknown parameter `%s'\n",
157 "%s: `%s' too large for parameter `%s'\n",
158 name
, val
?: "", param
);
164 "%s: `%s' invalid for parameter `%s'\n",
165 name
, val
?: "", param
);
174 /* Lazy bastard, eh? */
175 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
176 int param_set_##name(const char *val, struct kernel_param *kp) \
181 if (!val) return -EINVAL; \
182 l = strtolfn(val, &endp, 0); \
183 if (endp == val || ((type)l != l)) \
185 *((type *)kp->arg) = l; \
188 int param_get_##name(char *buffer, struct kernel_param *kp) \
190 return sprintf(buffer, format, *((type *)kp->arg)); \
193 STANDARD_PARAM_DEF(byte
, unsigned char, "%c", unsigned long, simple_strtoul
);
194 STANDARD_PARAM_DEF(short, short, "%hi", long, simple_strtol
);
195 STANDARD_PARAM_DEF(ushort
, unsigned short, "%hu", unsigned long, simple_strtoul
);
196 STANDARD_PARAM_DEF(int, int, "%i", long, simple_strtol
);
197 STANDARD_PARAM_DEF(uint
, unsigned int, "%u", unsigned long, simple_strtoul
);
198 STANDARD_PARAM_DEF(long, long, "%li", long, simple_strtol
);
199 STANDARD_PARAM_DEF(ulong
, unsigned long, "%lu", unsigned long, simple_strtoul
);
201 int param_set_charp(const char *val
, struct kernel_param
*kp
)
204 printk(KERN_ERR
"%s: string parameter expected\n",
209 if (strlen(val
) > 1024) {
210 printk(KERN_ERR
"%s: string parameter too long\n",
215 *(char **)kp
->arg
= (char *)val
;
219 int param_get_charp(char *buffer
, struct kernel_param
*kp
)
221 return sprintf(buffer
, "%s", *((char **)kp
->arg
));
224 int param_set_bool(const char *val
, struct kernel_param
*kp
)
226 /* No equals means "set"... */
229 /* One of =[yYnN01] */
231 case 'y': case 'Y': case '1':
234 case 'n': case 'N': case '0':
241 int param_get_bool(char *buffer
, struct kernel_param
*kp
)
243 /* Y and N chosen as being relatively non-coder friendly */
244 return sprintf(buffer
, "%c", (*(int *)kp
->arg
) ? 'Y' : 'N');
247 int param_set_invbool(const char *val
, struct kernel_param
*kp
)
250 struct kernel_param dummy
= { .arg
= &boolval
};
252 ret
= param_set_bool(val
, &dummy
);
254 *(int *)kp
->arg
= !boolval
;
258 int param_get_invbool(char *buffer
, struct kernel_param
*kp
)
261 struct kernel_param dummy
= { .arg
= &val
};
263 val
= !*(int *)kp
->arg
;
264 return param_get_bool(buffer
, &dummy
);
267 /* We cheat here and temporarily mangle the string. */
268 int param_array(const char *name
,
270 unsigned int min
, unsigned int max
,
271 void *elem
, int elemsize
,
272 int (*set
)(const char *, struct kernel_param
*kp
),
276 struct kernel_param kp
;
279 /* Get the name right for errors. */
283 /* No equals sign? */
285 printk(KERN_ERR
"%s: expects arguments\n", name
);
290 /* We expect a comma-separated list of values. */
295 printk(KERN_ERR
"%s: can only take %i arguments\n",
299 len
= strcspn(val
, ",");
301 /* nul-terminate and parse */
303 ((char *)val
)[len
] = '\0';
311 } while (save
== ',');
314 printk(KERN_ERR
"%s: needs at least %i arguments\n",
321 int param_array_set(const char *val
, struct kernel_param
*kp
)
323 struct kparam_array
*arr
= kp
->arg
;
324 unsigned int temp_num
;
326 return param_array(kp
->name
, val
, 1, arr
->max
, arr
->elem
,
327 arr
->elemsize
, arr
->set
, arr
->num
?: &temp_num
);
330 int param_array_get(char *buffer
, struct kernel_param
*kp
)
333 struct kparam_array
*arr
= kp
->arg
;
334 struct kernel_param p
;
337 for (i
= off
= 0; i
< (arr
->num
? *arr
->num
: arr
->max
); i
++) {
340 p
.arg
= arr
->elem
+ arr
->elemsize
* i
;
341 ret
= arr
->get(buffer
+ off
, &p
);
350 int param_set_copystring(const char *val
, struct kernel_param
*kp
)
352 struct kparam_string
*kps
= kp
->arg
;
354 if (strlen(val
)+1 > kps
->maxlen
) {
355 printk(KERN_ERR
"%s: string doesn't fit in %u chars.\n",
356 kp
->name
, kps
->maxlen
-1);
359 strcpy(kps
->string
, val
);
363 int param_get_string(char *buffer
, struct kernel_param
*kp
)
365 struct kparam_string
*kps
= kp
->arg
;
366 return strlcpy(buffer
, kps
->string
, kps
->maxlen
);
369 /* sysfs output in /sys/modules/XYZ/parameters/ */
371 extern struct kernel_param __start___param
[], __stop___param
[];
373 #define MAX_KBUILD_MODNAME KOBJ_NAME_LEN
375 struct param_attribute
377 struct module_attribute mattr
;
378 struct kernel_param
*param
;
381 struct module_param_attrs
383 struct attribute_group grp
;
384 struct param_attribute attrs
[0];
387 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
389 static ssize_t
param_attr_show(struct module_attribute
*mattr
,
390 struct module
*mod
, char *buf
)
393 struct param_attribute
*attribute
= to_param_attr(mattr
);
395 if (!attribute
->param
->get
)
398 count
= attribute
->param
->get(buf
, attribute
->param
);
406 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
407 static ssize_t
param_attr_store(struct module_attribute
*mattr
,
408 struct module
*owner
,
409 const char *buf
, size_t len
)
412 struct param_attribute
*attribute
= to_param_attr(mattr
);
414 if (!attribute
->param
->set
)
417 err
= attribute
->param
->set(buf
, attribute
->param
);
423 #ifdef CONFIG_MODULES
426 #define __modinit __init
430 * param_sysfs_setup - setup sysfs support for one module or KBUILD_MODNAME
431 * @mk: struct module_kobject (contains parent kobject)
432 * @kparam: array of struct kernel_param, the actual parameter definitions
433 * @num_params: number of entries in array
434 * @name_skip: offset where the parameter name start in kparam[].name. Needed for built-in "modules"
436 * Create a kobject for a (per-module) group of parameters, and create files
437 * in sysfs. A pointer to the param_kobject is returned on success,
438 * NULL if there's no parameter to export, or other ERR_PTR(err).
440 static __modinit
struct module_param_attrs
*
441 param_sysfs_setup(struct module_kobject
*mk
,
442 struct kernel_param
*kparam
,
443 unsigned int num_params
,
444 unsigned int name_skip
)
446 struct module_param_attrs
*mp
;
447 unsigned int valid_attrs
= 0;
448 unsigned int i
, size
[2];
449 struct param_attribute
*pattr
;
450 struct attribute
**gattr
;
453 for (i
=0; i
<num_params
; i
++) {
461 size
[0] = ALIGN(sizeof(*mp
) +
462 valid_attrs
* sizeof(mp
->attrs
[0]),
463 sizeof(mp
->grp
.attrs
[0]));
464 size
[1] = (valid_attrs
+ 1) * sizeof(mp
->grp
.attrs
[0]);
466 mp
= kmalloc(size
[0] + size
[1], GFP_KERNEL
);
468 return ERR_PTR(-ENOMEM
);
470 mp
->grp
.name
= "parameters";
471 mp
->grp
.attrs
= (void *)mp
+ size
[0];
473 pattr
= &mp
->attrs
[0];
474 gattr
= &mp
->grp
.attrs
[0];
475 for (i
= 0; i
< num_params
; i
++) {
476 struct kernel_param
*kp
= &kparam
[i
];
479 pattr
->mattr
.show
= param_attr_show
;
480 pattr
->mattr
.store
= param_attr_store
;
481 pattr
->mattr
.attr
.name
= (char *)&kp
->name
[name_skip
];
482 pattr
->mattr
.attr
.owner
= mk
->mod
;
483 pattr
->mattr
.attr
.mode
= kp
->perm
;
484 *(gattr
++) = &(pattr
++)->mattr
.attr
;
489 if ((err
= sysfs_create_group(&mk
->kobj
, &mp
->grp
))) {
497 #ifdef CONFIG_MODULES
500 * module_param_sysfs_setup - setup sysfs support for one module
502 * @kparam: module parameters (array)
503 * @num_params: number of module parameters
505 * Adds sysfs entries for module parameters, and creates a link from
506 * /sys/module/[mod->name]/parameters to /sys/parameters/[mod->name]/
508 int module_param_sysfs_setup(struct module
*mod
,
509 struct kernel_param
*kparam
,
510 unsigned int num_params
)
512 struct module_param_attrs
*mp
;
514 mp
= param_sysfs_setup(&mod
->mkobj
, kparam
, num_params
, 0);
518 mod
->param_attrs
= mp
;
523 * module_param_sysfs_remove - remove sysfs support for one module
526 * Remove sysfs entries for module parameters and the corresponding
529 void module_param_sysfs_remove(struct module
*mod
)
531 if (mod
->param_attrs
) {
532 sysfs_remove_group(&mod
->mkobj
.kobj
,
533 &mod
->param_attrs
->grp
);
534 /* We are positive that no one is using any param
535 * attrs at this point. Deallocate immediately. */
536 kfree(mod
->param_attrs
);
537 mod
->param_attrs
= NULL
;
543 * kernel_param_sysfs_setup - wrapper for built-in params support
545 static void __init
kernel_param_sysfs_setup(const char *name
,
546 struct kernel_param
*kparam
,
547 unsigned int num_params
,
548 unsigned int name_skip
)
550 struct module_kobject
*mk
;
552 mk
= kzalloc(sizeof(struct module_kobject
), GFP_KERNEL
);
555 mk
->mod
= THIS_MODULE
;
556 kobj_set_kset_s(mk
, module_subsys
);
557 kobject_set_name(&mk
->kobj
, name
);
558 kobject_register(&mk
->kobj
);
560 /* no need to keep the kobject if no parameter is exported */
561 if (!param_sysfs_setup(mk
, kparam
, num_params
, name_skip
)) {
562 kobject_unregister(&mk
->kobj
);
568 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
570 * Add module_parameters to sysfs for "modules" built into the kernel.
572 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
573 * "parameter" name is stored behind a dot in kernel_param->name. So,
574 * extract the "module" name for all built-in kernel_param-eters,
575 * and for all who have the same, call kernel_param_sysfs_setup.
577 static void __init
param_sysfs_builtin(void)
579 struct kernel_param
*kp
, *kp_begin
= NULL
;
580 unsigned int i
, name_len
, count
= 0;
581 char modname
[MAX_KBUILD_MODNAME
+ 1] = "";
583 for (i
=0; i
< __stop___param
- __start___param
; i
++) {
586 kp
= &__start___param
[i
];
588 /* We do not handle args without periods. */
589 dot
= memchr(kp
->name
, '.', MAX_KBUILD_MODNAME
);
591 DEBUGP("couldn't find period in %s\n", kp
->name
);
594 name_len
= dot
- kp
->name
;
596 /* new kbuild_modname? */
597 if (strlen(modname
) != name_len
598 || strncmp(modname
, kp
->name
, name_len
) != 0) {
599 /* add a new kobject for previous kernel_params. */
601 kernel_param_sysfs_setup(modname
,
606 strncpy(modname
, kp
->name
, name_len
);
607 modname
[name_len
] = '\0';
614 /* last kernel_params need to be registered as well */
616 kernel_param_sysfs_setup(modname
, kp_begin
, count
,
621 /* module-related sysfs stuff */
624 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
625 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
627 static ssize_t
module_attr_show(struct kobject
*kobj
,
628 struct attribute
*attr
,
631 struct module_attribute
*attribute
;
632 struct module_kobject
*mk
;
635 attribute
= to_module_attr(attr
);
636 mk
= to_module_kobject(kobj
);
638 if (!attribute
->show
)
641 if (!try_module_get(mk
->mod
))
644 ret
= attribute
->show(attribute
, mk
->mod
, buf
);
651 static ssize_t
module_attr_store(struct kobject
*kobj
,
652 struct attribute
*attr
,
653 const char *buf
, size_t len
)
655 struct module_attribute
*attribute
;
656 struct module_kobject
*mk
;
659 attribute
= to_module_attr(attr
);
660 mk
= to_module_kobject(kobj
);
662 if (!attribute
->store
)
665 if (!try_module_get(mk
->mod
))
668 ret
= attribute
->store(attribute
, mk
->mod
, buf
, len
);
675 static struct sysfs_ops module_sysfs_ops
= {
676 .show
= module_attr_show
,
677 .store
= module_attr_store
,
681 static struct sysfs_ops module_sysfs_ops
= {
687 static struct kobj_type module_ktype
= {
688 .sysfs_ops
= &module_sysfs_ops
,
691 decl_subsys(module
, &module_ktype
, NULL
);
694 * param_sysfs_init - wrapper for built-in params support
696 static int __init
param_sysfs_init(void)
698 subsystem_register(&module_subsys
);
700 param_sysfs_builtin();
704 __initcall(param_sysfs_init
);
706 EXPORT_SYMBOL(param_set_byte
);
707 EXPORT_SYMBOL(param_get_byte
);
708 EXPORT_SYMBOL(param_set_short
);
709 EXPORT_SYMBOL(param_get_short
);
710 EXPORT_SYMBOL(param_set_ushort
);
711 EXPORT_SYMBOL(param_get_ushort
);
712 EXPORT_SYMBOL(param_set_int
);
713 EXPORT_SYMBOL(param_get_int
);
714 EXPORT_SYMBOL(param_set_uint
);
715 EXPORT_SYMBOL(param_get_uint
);
716 EXPORT_SYMBOL(param_set_long
);
717 EXPORT_SYMBOL(param_get_long
);
718 EXPORT_SYMBOL(param_set_ulong
);
719 EXPORT_SYMBOL(param_get_ulong
);
720 EXPORT_SYMBOL(param_set_charp
);
721 EXPORT_SYMBOL(param_get_charp
);
722 EXPORT_SYMBOL(param_set_bool
);
723 EXPORT_SYMBOL(param_get_bool
);
724 EXPORT_SYMBOL(param_set_invbool
);
725 EXPORT_SYMBOL(param_get_invbool
);
726 EXPORT_SYMBOL(param_array_set
);
727 EXPORT_SYMBOL(param_array_get
);
728 EXPORT_SYMBOL(param_set_copystring
);
729 EXPORT_SYMBOL(param_get_string
);