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 ret = strtolfn(val, 0, &l); \
188 if (ret == -EINVAL || ((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, strict_strtoul
);
199 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol
);
200 STANDARD_PARAM_DEF(ushort
, unsigned short, "%hu", unsigned long, strict_strtoul
);
201 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol
);
202 STANDARD_PARAM_DEF(uint
, unsigned int, "%u", unsigned long, strict_strtoul
);
203 STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol
);
204 STANDARD_PARAM_DEF(ulong
, unsigned long, "%lu", unsigned long, strict_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 if (kp
->flags
& KPARAM_KMALLOCED
)
221 kfree(*(char **)kp
->arg
);
223 /* This is a hack. We can't need to strdup in early boot, and we
224 * don't need to; this mangled commandline is preserved. */
225 if (slab_is_available()) {
226 kp
->flags
|= KPARAM_KMALLOCED
;
227 *(char **)kp
->arg
= kstrdup(val
, GFP_KERNEL
);
231 *(const char **)kp
->arg
= val
;
236 int param_get_charp(char *buffer
, struct kernel_param
*kp
)
238 return sprintf(buffer
, "%s", *((char **)kp
->arg
));
241 /* Actually could be a bool or an int, for historical reasons. */
242 int param_set_bool(const char *val
, struct kernel_param
*kp
)
246 /* No equals means "set"... */
249 /* One of =[yYnN01] */
251 case 'y': case 'Y': case '1':
254 case 'n': case 'N': case '0':
261 if (kp
->flags
& KPARAM_ISBOOL
)
262 *(bool *)kp
->arg
= v
;
268 int param_get_bool(char *buffer
, struct kernel_param
*kp
)
271 if (kp
->flags
& KPARAM_ISBOOL
)
272 val
= *(bool *)kp
->arg
;
274 val
= *(int *)kp
->arg
;
276 /* Y and N chosen as being relatively non-coder friendly */
277 return sprintf(buffer
, "%c", val
? 'Y' : 'N');
280 /* This one must be bool. */
281 int param_set_invbool(const char *val
, struct kernel_param
*kp
)
285 struct kernel_param dummy
;
287 dummy
.arg
= &boolval
;
288 dummy
.flags
= KPARAM_ISBOOL
;
289 ret
= param_set_bool(val
, &dummy
);
291 *(bool *)kp
->arg
= !boolval
;
295 int param_get_invbool(char *buffer
, struct kernel_param
*kp
)
297 return sprintf(buffer
, "%c", (*(bool *)kp
->arg
) ? 'N' : 'Y');
300 /* We break the rule and mangle the string. */
301 static int param_array(const char *name
,
303 unsigned int min
, unsigned int max
,
304 void *elem
, int elemsize
,
305 int (*set
)(const char *, struct kernel_param
*kp
),
309 struct kernel_param kp
;
312 /* Get the name right for errors. */
316 /* No equals sign? */
318 printk(KERN_ERR
"%s: expects arguments\n", name
);
323 /* We expect a comma-separated list of values. */
328 printk(KERN_ERR
"%s: can only take %i arguments\n",
332 len
= strcspn(val
, ",");
334 /* nul-terminate and parse */
336 ((char *)val
)[len
] = '\0';
344 } while (save
== ',');
347 printk(KERN_ERR
"%s: needs at least %i arguments\n",
354 int param_array_set(const char *val
, struct kernel_param
*kp
)
356 const struct kparam_array
*arr
= kp
->arr
;
357 unsigned int temp_num
;
359 return param_array(kp
->name
, val
, 1, arr
->max
, arr
->elem
,
360 arr
->elemsize
, arr
->set
, arr
->num
?: &temp_num
);
363 int param_array_get(char *buffer
, struct kernel_param
*kp
)
366 const struct kparam_array
*arr
= kp
->arr
;
367 struct kernel_param p
;
370 for (i
= off
= 0; i
< (arr
->num
? *arr
->num
: arr
->max
); i
++) {
373 p
.arg
= arr
->elem
+ arr
->elemsize
* i
;
374 ret
= arr
->get(buffer
+ off
, &p
);
383 int param_set_copystring(const char *val
, struct kernel_param
*kp
)
385 const struct kparam_string
*kps
= kp
->str
;
388 printk(KERN_ERR
"%s: missing param set value\n", kp
->name
);
391 if (strlen(val
)+1 > kps
->maxlen
) {
392 printk(KERN_ERR
"%s: string doesn't fit in %u chars.\n",
393 kp
->name
, kps
->maxlen
-1);
396 strcpy(kps
->string
, val
);
400 int param_get_string(char *buffer
, struct kernel_param
*kp
)
402 const struct kparam_string
*kps
= kp
->str
;
403 return strlcpy(buffer
, kps
->string
, kps
->maxlen
);
406 /* sysfs output in /sys/modules/XYZ/parameters/ */
407 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
408 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
410 extern struct kernel_param __start___param
[], __stop___param
[];
412 struct param_attribute
414 struct module_attribute mattr
;
415 struct kernel_param
*param
;
418 struct module_param_attrs
421 struct attribute_group grp
;
422 struct param_attribute attrs
[0];
426 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
428 static ssize_t
param_attr_show(struct module_attribute
*mattr
,
429 struct module
*mod
, char *buf
)
432 struct param_attribute
*attribute
= to_param_attr(mattr
);
434 if (!attribute
->param
->get
)
437 count
= attribute
->param
->get(buf
, attribute
->param
);
445 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
446 static ssize_t
param_attr_store(struct module_attribute
*mattr
,
447 struct module
*owner
,
448 const char *buf
, size_t len
)
451 struct param_attribute
*attribute
= to_param_attr(mattr
);
453 if (!attribute
->param
->set
)
456 err
= attribute
->param
->set(buf
, attribute
->param
);
463 #ifdef CONFIG_MODULES
466 #define __modinit __init
471 * add_sysfs_param - add a parameter to sysfs
472 * @mk: struct module_kobject
473 * @kparam: the actual parameter definition to add to sysfs
474 * @name: name of parameter
476 * Create a kobject if for a (per-module) parameter if mp NULL, and
477 * create file in sysfs. Returns an error on out of memory. Always cleans up
478 * if there's an error.
480 static __modinit
int add_sysfs_param(struct module_kobject
*mk
,
481 struct kernel_param
*kp
,
484 struct module_param_attrs
*new;
485 struct attribute
**attrs
;
488 /* We don't bother calling this with invisible parameters. */
496 attrs
= mk
->mp
->grp
.attrs
;
500 new = krealloc(mk
->mp
,
501 sizeof(*mk
->mp
) + sizeof(mk
->mp
->attrs
[0]) * (num
+1),
508 attrs
= krealloc(attrs
, sizeof(new->grp
.attrs
[0])*(num
+2), GFP_KERNEL
);
514 /* Sysfs wants everything zeroed. */
515 memset(new, 0, sizeof(*new));
516 memset(&new->attrs
[num
], 0, sizeof(new->attrs
[num
]));
517 memset(&attrs
[num
], 0, sizeof(attrs
[num
]));
518 new->grp
.name
= "parameters";
519 new->grp
.attrs
= attrs
;
521 /* Tack new one on the end. */
522 new->attrs
[num
].param
= kp
;
523 new->attrs
[num
].mattr
.show
= param_attr_show
;
524 new->attrs
[num
].mattr
.store
= param_attr_store
;
525 new->attrs
[num
].mattr
.attr
.name
= (char *)name
;
526 new->attrs
[num
].mattr
.attr
.mode
= kp
->perm
;
529 /* Fix up all the pointers, since krealloc can move us */
530 for (num
= 0; num
< new->num
; num
++)
531 new->grp
.attrs
[num
] = &new->attrs
[num
].mattr
.attr
;
532 new->grp
.attrs
[num
] = NULL
;
544 #ifdef CONFIG_MODULES
545 static void free_module_param_attrs(struct module_kobject
*mk
)
547 kfree(mk
->mp
->grp
.attrs
);
553 * module_param_sysfs_setup - setup sysfs support for one module
555 * @kparam: module parameters (array)
556 * @num_params: number of module parameters
558 * Adds sysfs entries for module parameters under
559 * /sys/module/[mod->name]/parameters/
561 int module_param_sysfs_setup(struct module
*mod
,
562 struct kernel_param
*kparam
,
563 unsigned int num_params
)
568 for (i
= 0; i
< num_params
; i
++) {
569 if (kparam
[i
].perm
== 0)
571 err
= add_sysfs_param(&mod
->mkobj
, &kparam
[i
], kparam
[i
].name
);
580 /* Create the param group. */
581 err
= sysfs_create_group(&mod
->mkobj
.kobj
, &mod
->mkobj
.mp
->grp
);
583 free_module_param_attrs(&mod
->mkobj
);
588 * module_param_sysfs_remove - remove sysfs support for one module
591 * Remove sysfs entries for module parameters and the corresponding
594 void module_param_sysfs_remove(struct module
*mod
)
597 sysfs_remove_group(&mod
->mkobj
.kobj
, &mod
->mkobj
.mp
->grp
);
598 /* We are positive that no one is using any param
599 * attrs at this point. Deallocate immediately. */
600 free_module_param_attrs(&mod
->mkobj
);
605 void destroy_params(const struct kernel_param
*params
, unsigned num
)
609 for (i
= 0; i
< num
; i
++)
610 if (params
[i
].flags
& KPARAM_KMALLOCED
)
611 kfree(*(char **)params
[i
].arg
);
614 static void __init
kernel_add_sysfs_param(const char *name
,
615 struct kernel_param
*kparam
,
616 unsigned int name_skip
)
618 struct module_kobject
*mk
;
619 struct kobject
*kobj
;
622 kobj
= kset_find_obj(module_kset
, name
);
624 /* We already have one. Remove params so we can add more. */
625 mk
= to_module_kobject(kobj
);
626 /* We need to remove it before adding parameters. */
627 sysfs_remove_group(&mk
->kobj
, &mk
->mp
->grp
);
629 mk
= kzalloc(sizeof(struct module_kobject
), GFP_KERNEL
);
632 mk
->mod
= THIS_MODULE
;
633 mk
->kobj
.kset
= module_kset
;
634 err
= kobject_init_and_add(&mk
->kobj
, &module_ktype
, NULL
,
637 kobject_put(&mk
->kobj
);
638 printk(KERN_ERR
"Module '%s' failed add to sysfs, "
639 "error number %d\n", name
, err
);
640 printk(KERN_ERR
"The system will be unstable now.\n");
643 /* So that exit path is even. */
644 kobject_get(&mk
->kobj
);
647 /* These should not fail at boot. */
648 err
= add_sysfs_param(mk
, kparam
, kparam
->name
+ name_skip
);
650 err
= sysfs_create_group(&mk
->kobj
, &mk
->mp
->grp
);
652 kobject_uevent(&mk
->kobj
, KOBJ_ADD
);
653 kobject_put(&mk
->kobj
);
657 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
659 * Add module_parameters to sysfs for "modules" built into the kernel.
661 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
662 * "parameter" name is stored behind a dot in kernel_param->name. So,
663 * extract the "module" name for all built-in kernel_param-eters,
664 * and for all who have the same, call kernel_add_sysfs_param.
666 static void __init
param_sysfs_builtin(void)
668 struct kernel_param
*kp
;
669 unsigned int name_len
;
670 char modname
[MODULE_NAME_LEN
];
672 for (kp
= __start___param
; kp
< __stop___param
; kp
++) {
678 dot
= strchr(kp
->name
, '.');
680 /* This happens for core_param() */
681 strcpy(modname
, "kernel");
684 name_len
= dot
- kp
->name
+ 1;
685 strlcpy(modname
, kp
->name
, name_len
);
687 kernel_add_sysfs_param(modname
, kp
, name_len
);
692 /* module-related sysfs stuff */
694 static ssize_t
module_attr_show(struct kobject
*kobj
,
695 struct attribute
*attr
,
698 struct module_attribute
*attribute
;
699 struct module_kobject
*mk
;
702 attribute
= to_module_attr(attr
);
703 mk
= to_module_kobject(kobj
);
705 if (!attribute
->show
)
708 ret
= attribute
->show(attribute
, mk
->mod
, buf
);
713 static ssize_t
module_attr_store(struct kobject
*kobj
,
714 struct attribute
*attr
,
715 const char *buf
, size_t len
)
717 struct module_attribute
*attribute
;
718 struct module_kobject
*mk
;
721 attribute
= to_module_attr(attr
);
722 mk
= to_module_kobject(kobj
);
724 if (!attribute
->store
)
727 ret
= attribute
->store(attribute
, mk
->mod
, buf
, len
);
732 static struct sysfs_ops module_sysfs_ops
= {
733 .show
= module_attr_show
,
734 .store
= module_attr_store
,
737 static int uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
739 struct kobj_type
*ktype
= get_ktype(kobj
);
741 if (ktype
== &module_ktype
)
746 static struct kset_uevent_ops module_uevent_ops
= {
747 .filter
= uevent_filter
,
750 struct kset
*module_kset
;
751 int module_sysfs_initialized
;
753 struct kobj_type module_ktype
= {
754 .sysfs_ops
= &module_sysfs_ops
,
758 * param_sysfs_init - wrapper for built-in params support
760 static int __init
param_sysfs_init(void)
762 module_kset
= kset_create_and_add("module", &module_uevent_ops
, NULL
);
764 printk(KERN_WARNING
"%s (%d): error creating kset\n",
768 module_sysfs_initialized
= 1;
770 param_sysfs_builtin();
774 subsys_initcall(param_sysfs_init
);
776 #endif /* CONFIG_SYSFS */
778 EXPORT_SYMBOL(param_set_byte
);
779 EXPORT_SYMBOL(param_get_byte
);
780 EXPORT_SYMBOL(param_set_short
);
781 EXPORT_SYMBOL(param_get_short
);
782 EXPORT_SYMBOL(param_set_ushort
);
783 EXPORT_SYMBOL(param_get_ushort
);
784 EXPORT_SYMBOL(param_set_int
);
785 EXPORT_SYMBOL(param_get_int
);
786 EXPORT_SYMBOL(param_set_uint
);
787 EXPORT_SYMBOL(param_get_uint
);
788 EXPORT_SYMBOL(param_set_long
);
789 EXPORT_SYMBOL(param_get_long
);
790 EXPORT_SYMBOL(param_set_ulong
);
791 EXPORT_SYMBOL(param_get_ulong
);
792 EXPORT_SYMBOL(param_set_charp
);
793 EXPORT_SYMBOL(param_get_charp
);
794 EXPORT_SYMBOL(param_set_bool
);
795 EXPORT_SYMBOL(param_get_bool
);
796 EXPORT_SYMBOL(param_set_invbool
);
797 EXPORT_SYMBOL(param_get_invbool
);
798 EXPORT_SYMBOL(param_array_set
);
799 EXPORT_SYMBOL(param_array_get
);
800 EXPORT_SYMBOL(param_set_copystring
);
801 EXPORT_SYMBOL(param_get_string
);