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>
31 #define DEBUGP(fmt, a...)
34 static inline char 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 (isspace(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. */
125 while (isspace(*next
))
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 */
142 while (isspace(*args
))
147 int irq_was_disabled
;
149 args
= next_arg(args
, ¶m
, &val
);
150 irq_was_disabled
= irqs_disabled();
151 ret
= parse_one(param
, val
, params
, num
, unknown
);
152 if (irq_was_disabled
&& !irqs_disabled()) {
153 printk(KERN_WARNING
"parse_args(): option '%s' enabled "
158 printk(KERN_ERR
"%s: Unknown parameter `%s'\n",
163 "%s: `%s' too large for parameter `%s'\n",
164 name
, val
?: "", param
);
170 "%s: `%s' invalid for parameter `%s'\n",
171 name
, val
?: "", param
);
180 /* Lazy bastard, eh? */
181 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
182 int param_set_##name(const char *val, struct kernel_param *kp) \
187 if (!val) return -EINVAL; \
188 ret = strtolfn(val, 0, &l); \
189 if (ret == -EINVAL || ((type)l != l)) \
191 *((type *)kp->arg) = l; \
194 int param_get_##name(char *buffer, struct kernel_param *kp) \
196 return sprintf(buffer, format, *((type *)kp->arg)); \
199 STANDARD_PARAM_DEF(byte
, unsigned char, "%c", unsigned long, strict_strtoul
);
200 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol
);
201 STANDARD_PARAM_DEF(ushort
, unsigned short, "%hu", unsigned long, strict_strtoul
);
202 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol
);
203 STANDARD_PARAM_DEF(uint
, unsigned int, "%u", unsigned long, strict_strtoul
);
204 STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol
);
205 STANDARD_PARAM_DEF(ulong
, unsigned long, "%lu", unsigned long, strict_strtoul
);
207 int param_set_charp(const char *val
, struct kernel_param
*kp
)
210 printk(KERN_ERR
"%s: string parameter expected\n",
215 if (strlen(val
) > 1024) {
216 printk(KERN_ERR
"%s: string parameter too long\n",
221 if (kp
->flags
& KPARAM_KMALLOCED
)
222 kfree(*(char **)kp
->arg
);
224 /* This is a hack. We can't need to strdup in early boot, and we
225 * don't need to; this mangled commandline is preserved. */
226 if (slab_is_available()) {
227 kp
->flags
|= KPARAM_KMALLOCED
;
228 *(char **)kp
->arg
= kstrdup(val
, GFP_KERNEL
);
232 *(const char **)kp
->arg
= val
;
237 int param_get_charp(char *buffer
, struct kernel_param
*kp
)
239 return sprintf(buffer
, "%s", *((char **)kp
->arg
));
242 /* Actually could be a bool or an int, for historical reasons. */
243 int param_set_bool(const char *val
, struct kernel_param
*kp
)
247 /* No equals means "set"... */
250 /* One of =[yYnN01] */
252 case 'y': case 'Y': case '1':
255 case 'n': case 'N': case '0':
262 if (kp
->flags
& KPARAM_ISBOOL
)
263 *(bool *)kp
->arg
= v
;
269 int param_get_bool(char *buffer
, struct kernel_param
*kp
)
272 if (kp
->flags
& KPARAM_ISBOOL
)
273 val
= *(bool *)kp
->arg
;
275 val
= *(int *)kp
->arg
;
277 /* Y and N chosen as being relatively non-coder friendly */
278 return sprintf(buffer
, "%c", val
? 'Y' : 'N');
281 /* This one must be bool. */
282 int param_set_invbool(const char *val
, struct kernel_param
*kp
)
286 struct kernel_param dummy
;
288 dummy
.arg
= &boolval
;
289 dummy
.flags
= KPARAM_ISBOOL
;
290 ret
= param_set_bool(val
, &dummy
);
292 *(bool *)kp
->arg
= !boolval
;
296 int param_get_invbool(char *buffer
, struct kernel_param
*kp
)
298 return sprintf(buffer
, "%c", (*(bool *)kp
->arg
) ? 'N' : 'Y');
301 /* We break the rule and mangle the string. */
302 static int param_array(const char *name
,
304 unsigned int min
, unsigned int max
,
305 void *elem
, int elemsize
,
306 int (*set
)(const char *, struct kernel_param
*kp
),
310 struct kernel_param kp
;
313 /* Get the name right for errors. */
317 /* No equals sign? */
319 printk(KERN_ERR
"%s: expects arguments\n", name
);
324 /* We expect a comma-separated list of values. */
329 printk(KERN_ERR
"%s: can only take %i arguments\n",
333 len
= strcspn(val
, ",");
335 /* nul-terminate and parse */
337 ((char *)val
)[len
] = '\0';
345 } while (save
== ',');
348 printk(KERN_ERR
"%s: needs at least %i arguments\n",
355 int param_array_set(const char *val
, struct kernel_param
*kp
)
357 const struct kparam_array
*arr
= kp
->arr
;
358 unsigned int temp_num
;
360 return param_array(kp
->name
, val
, 1, arr
->max
, arr
->elem
,
361 arr
->elemsize
, arr
->set
, arr
->num
?: &temp_num
);
364 int param_array_get(char *buffer
, struct kernel_param
*kp
)
367 const struct kparam_array
*arr
= kp
->arr
;
368 struct kernel_param p
;
371 for (i
= off
= 0; i
< (arr
->num
? *arr
->num
: arr
->max
); i
++) {
374 p
.arg
= arr
->elem
+ arr
->elemsize
* i
;
375 ret
= arr
->get(buffer
+ off
, &p
);
384 int param_set_copystring(const char *val
, struct kernel_param
*kp
)
386 const struct kparam_string
*kps
= kp
->str
;
389 printk(KERN_ERR
"%s: missing param set value\n", kp
->name
);
392 if (strlen(val
)+1 > kps
->maxlen
) {
393 printk(KERN_ERR
"%s: string doesn't fit in %u chars.\n",
394 kp
->name
, kps
->maxlen
-1);
397 strcpy(kps
->string
, val
);
401 int param_get_string(char *buffer
, struct kernel_param
*kp
)
403 const struct kparam_string
*kps
= kp
->str
;
404 return strlcpy(buffer
, kps
->string
, kps
->maxlen
);
407 /* sysfs output in /sys/modules/XYZ/parameters/ */
408 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
409 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
411 extern struct kernel_param __start___param
[], __stop___param
[];
413 struct param_attribute
415 struct module_attribute mattr
;
416 struct kernel_param
*param
;
419 struct module_param_attrs
422 struct attribute_group grp
;
423 struct param_attribute attrs
[0];
427 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
429 static ssize_t
param_attr_show(struct module_attribute
*mattr
,
430 struct module
*mod
, char *buf
)
433 struct param_attribute
*attribute
= to_param_attr(mattr
);
435 if (!attribute
->param
->get
)
438 count
= attribute
->param
->get(buf
, attribute
->param
);
446 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
447 static ssize_t
param_attr_store(struct module_attribute
*mattr
,
448 struct module
*owner
,
449 const char *buf
, size_t len
)
452 struct param_attribute
*attribute
= to_param_attr(mattr
);
454 if (!attribute
->param
->set
)
457 err
= attribute
->param
->set(buf
, attribute
->param
);
464 #ifdef CONFIG_MODULES
467 #define __modinit __init
472 * add_sysfs_param - add a parameter to sysfs
473 * @mk: struct module_kobject
474 * @kparam: the actual parameter definition to add to sysfs
475 * @name: name of parameter
477 * Create a kobject if for a (per-module) parameter if mp NULL, and
478 * create file in sysfs. Returns an error on out of memory. Always cleans up
479 * if there's an error.
481 static __modinit
int add_sysfs_param(struct module_kobject
*mk
,
482 struct kernel_param
*kp
,
485 struct module_param_attrs
*new;
486 struct attribute
**attrs
;
489 /* We don't bother calling this with invisible parameters. */
497 attrs
= mk
->mp
->grp
.attrs
;
501 new = krealloc(mk
->mp
,
502 sizeof(*mk
->mp
) + sizeof(mk
->mp
->attrs
[0]) * (num
+1),
509 attrs
= krealloc(attrs
, sizeof(new->grp
.attrs
[0])*(num
+2), GFP_KERNEL
);
515 /* Sysfs wants everything zeroed. */
516 memset(new, 0, sizeof(*new));
517 memset(&new->attrs
[num
], 0, sizeof(new->attrs
[num
]));
518 memset(&attrs
[num
], 0, sizeof(attrs
[num
]));
519 new->grp
.name
= "parameters";
520 new->grp
.attrs
= attrs
;
522 /* Tack new one on the end. */
523 new->attrs
[num
].param
= kp
;
524 new->attrs
[num
].mattr
.show
= param_attr_show
;
525 new->attrs
[num
].mattr
.store
= param_attr_store
;
526 new->attrs
[num
].mattr
.attr
.name
= (char *)name
;
527 new->attrs
[num
].mattr
.attr
.mode
= kp
->perm
;
530 /* Fix up all the pointers, since krealloc can move us */
531 for (num
= 0; num
< new->num
; num
++)
532 new->grp
.attrs
[num
] = &new->attrs
[num
].mattr
.attr
;
533 new->grp
.attrs
[num
] = NULL
;
545 #ifdef CONFIG_MODULES
546 static void free_module_param_attrs(struct module_kobject
*mk
)
548 kfree(mk
->mp
->grp
.attrs
);
554 * module_param_sysfs_setup - setup sysfs support for one module
556 * @kparam: module parameters (array)
557 * @num_params: number of module parameters
559 * Adds sysfs entries for module parameters under
560 * /sys/module/[mod->name]/parameters/
562 int module_param_sysfs_setup(struct module
*mod
,
563 struct kernel_param
*kparam
,
564 unsigned int num_params
)
569 for (i
= 0; i
< num_params
; i
++) {
570 if (kparam
[i
].perm
== 0)
572 err
= add_sysfs_param(&mod
->mkobj
, &kparam
[i
], kparam
[i
].name
);
581 /* Create the param group. */
582 err
= sysfs_create_group(&mod
->mkobj
.kobj
, &mod
->mkobj
.mp
->grp
);
584 free_module_param_attrs(&mod
->mkobj
);
589 * module_param_sysfs_remove - remove sysfs support for one module
592 * Remove sysfs entries for module parameters and the corresponding
595 void module_param_sysfs_remove(struct module
*mod
)
598 sysfs_remove_group(&mod
->mkobj
.kobj
, &mod
->mkobj
.mp
->grp
);
599 /* We are positive that no one is using any param
600 * attrs at this point. Deallocate immediately. */
601 free_module_param_attrs(&mod
->mkobj
);
606 void destroy_params(const struct kernel_param
*params
, unsigned num
)
610 for (i
= 0; i
< num
; i
++)
611 if (params
[i
].flags
& KPARAM_KMALLOCED
)
612 kfree(*(char **)params
[i
].arg
);
615 static void __init
kernel_add_sysfs_param(const char *name
,
616 struct kernel_param
*kparam
,
617 unsigned int name_skip
)
619 struct module_kobject
*mk
;
620 struct kobject
*kobj
;
623 kobj
= kset_find_obj(module_kset
, name
);
625 /* We already have one. Remove params so we can add more. */
626 mk
= to_module_kobject(kobj
);
627 /* We need to remove it before adding parameters. */
628 sysfs_remove_group(&mk
->kobj
, &mk
->mp
->grp
);
630 mk
= kzalloc(sizeof(struct module_kobject
), GFP_KERNEL
);
633 mk
->mod
= THIS_MODULE
;
634 mk
->kobj
.kset
= module_kset
;
635 err
= kobject_init_and_add(&mk
->kobj
, &module_ktype
, NULL
,
638 kobject_put(&mk
->kobj
);
639 printk(KERN_ERR
"Module '%s' failed add to sysfs, "
640 "error number %d\n", name
, err
);
641 printk(KERN_ERR
"The system will be unstable now.\n");
644 /* So that exit path is even. */
645 kobject_get(&mk
->kobj
);
648 /* These should not fail at boot. */
649 err
= add_sysfs_param(mk
, kparam
, kparam
->name
+ name_skip
);
651 err
= sysfs_create_group(&mk
->kobj
, &mk
->mp
->grp
);
653 kobject_uevent(&mk
->kobj
, KOBJ_ADD
);
654 kobject_put(&mk
->kobj
);
658 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
660 * Add module_parameters to sysfs for "modules" built into the kernel.
662 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
663 * "parameter" name is stored behind a dot in kernel_param->name. So,
664 * extract the "module" name for all built-in kernel_param-eters,
665 * and for all who have the same, call kernel_add_sysfs_param.
667 static void __init
param_sysfs_builtin(void)
669 struct kernel_param
*kp
;
670 unsigned int name_len
;
671 char modname
[MODULE_NAME_LEN
];
673 for (kp
= __start___param
; kp
< __stop___param
; kp
++) {
679 dot
= strchr(kp
->name
, '.');
681 /* This happens for core_param() */
682 strcpy(modname
, "kernel");
685 name_len
= dot
- kp
->name
+ 1;
686 strlcpy(modname
, kp
->name
, name_len
);
688 kernel_add_sysfs_param(modname
, kp
, name_len
);
693 /* module-related sysfs stuff */
695 static ssize_t
module_attr_show(struct kobject
*kobj
,
696 struct attribute
*attr
,
699 struct module_attribute
*attribute
;
700 struct module_kobject
*mk
;
703 attribute
= to_module_attr(attr
);
704 mk
= to_module_kobject(kobj
);
706 if (!attribute
->show
)
709 ret
= attribute
->show(attribute
, mk
->mod
, buf
);
714 static ssize_t
module_attr_store(struct kobject
*kobj
,
715 struct attribute
*attr
,
716 const char *buf
, size_t len
)
718 struct module_attribute
*attribute
;
719 struct module_kobject
*mk
;
722 attribute
= to_module_attr(attr
);
723 mk
= to_module_kobject(kobj
);
725 if (!attribute
->store
)
728 ret
= attribute
->store(attribute
, mk
->mod
, buf
, len
);
733 static struct sysfs_ops module_sysfs_ops
= {
734 .show
= module_attr_show
,
735 .store
= module_attr_store
,
738 static int uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
740 struct kobj_type
*ktype
= get_ktype(kobj
);
742 if (ktype
== &module_ktype
)
747 static struct kset_uevent_ops module_uevent_ops
= {
748 .filter
= uevent_filter
,
751 struct kset
*module_kset
;
752 int module_sysfs_initialized
;
754 struct kobj_type module_ktype
= {
755 .sysfs_ops
= &module_sysfs_ops
,
759 * param_sysfs_init - wrapper for built-in params support
761 static int __init
param_sysfs_init(void)
763 module_kset
= kset_create_and_add("module", &module_uevent_ops
, NULL
);
765 printk(KERN_WARNING
"%s (%d): error creating kset\n",
769 module_sysfs_initialized
= 1;
771 param_sysfs_builtin();
775 subsys_initcall(param_sysfs_init
);
777 #endif /* CONFIG_SYSFS */
779 EXPORT_SYMBOL(param_set_byte
);
780 EXPORT_SYMBOL(param_get_byte
);
781 EXPORT_SYMBOL(param_set_short
);
782 EXPORT_SYMBOL(param_get_short
);
783 EXPORT_SYMBOL(param_set_ushort
);
784 EXPORT_SYMBOL(param_get_ushort
);
785 EXPORT_SYMBOL(param_set_int
);
786 EXPORT_SYMBOL(param_get_int
);
787 EXPORT_SYMBOL(param_set_uint
);
788 EXPORT_SYMBOL(param_get_uint
);
789 EXPORT_SYMBOL(param_set_long
);
790 EXPORT_SYMBOL(param_get_long
);
791 EXPORT_SYMBOL(param_set_ulong
);
792 EXPORT_SYMBOL(param_get_ulong
);
793 EXPORT_SYMBOL(param_set_charp
);
794 EXPORT_SYMBOL(param_get_charp
);
795 EXPORT_SYMBOL(param_set_bool
);
796 EXPORT_SYMBOL(param_get_bool
);
797 EXPORT_SYMBOL(param_set_invbool
);
798 EXPORT_SYMBOL(param_get_invbool
);
799 EXPORT_SYMBOL(param_array_set
);
800 EXPORT_SYMBOL(param_array_get
);
801 EXPORT_SYMBOL(param_set_copystring
);
802 EXPORT_SYMBOL(param_get_string
);