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>
27 /* We abuse the high bits of "perm" to record whether we kmalloc'ed. */
28 #define KPARAM_KMALLOCED 0x80000000
33 #define DEBUGP(fmt, a...)
36 static inline char dash2underscore(char c
)
43 static inline int parameq(const char *input
, const char *paramname
)
46 for (i
= 0; dash2underscore(input
[i
]) == paramname
[i
]; i
++)
52 static int parse_one(char *param
,
54 struct kernel_param
*params
,
56 int (*handle_unknown
)(char *param
, char *val
))
61 for (i
= 0; i
< num_params
; i
++) {
62 if (parameq(param
, params
[i
].name
)) {
63 DEBUGP("They are equal! Calling %p\n",
65 return params
[i
].set(val
, ¶ms
[i
]);
70 DEBUGP("Unknown argument: calling %p\n", handle_unknown
);
71 return handle_unknown(param
, val
);
74 DEBUGP("Unknown argument `%s'\n", param
);
78 /* You can use " around spaces, but can't escape ". */
79 /* Hyphens and underscores equivalent in parameter names. */
80 static char *next_arg(char *args
, char **param
, char **val
)
82 unsigned int i
, equals
= 0;
83 int in_quote
= 0, quoted
= 0;
92 for (i
= 0; args
[i
]; i
++) {
93 if (args
[i
] == ' ' && !in_quote
)
100 in_quote
= !in_quote
;
108 *val
= args
+ equals
+ 1;
110 /* Don't include quotes in value. */
113 if (args
[i
-1] == '"')
116 if (quoted
&& args
[i
-1] == '"')
126 /* Chew up trailing spaces. */
132 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
133 int parse_args(const char *name
,
135 struct kernel_param
*params
,
137 int (*unknown
)(char *param
, char *val
))
141 DEBUGP("Parsing ARGS: %s\n", args
);
143 /* Chew leading spaces */
149 int irq_was_disabled
;
151 args
= next_arg(args
, ¶m
, &val
);
152 irq_was_disabled
= irqs_disabled();
153 ret
= parse_one(param
, val
, params
, num
, unknown
);
154 if (irq_was_disabled
&& !irqs_disabled()) {
155 printk(KERN_WARNING
"parse_args(): option '%s' enabled "
160 printk(KERN_ERR
"%s: Unknown parameter `%s'\n",
165 "%s: `%s' too large for parameter `%s'\n",
166 name
, val
?: "", param
);
172 "%s: `%s' invalid for parameter `%s'\n",
173 name
, val
?: "", param
);
182 /* Lazy bastard, eh? */
183 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
184 int param_set_##name(const char *val, struct kernel_param *kp) \
189 if (!val) return -EINVAL; \
190 ret = strtolfn(val, 0, &l); \
191 if (ret == -EINVAL || ((type)l != l)) \
193 *((type *)kp->arg) = l; \
196 int param_get_##name(char *buffer, struct kernel_param *kp) \
198 return sprintf(buffer, format, *((type *)kp->arg)); \
201 STANDARD_PARAM_DEF(byte
, unsigned char, "%c", unsigned long, strict_strtoul
);
202 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol
);
203 STANDARD_PARAM_DEF(ushort
, unsigned short, "%hu", unsigned long, strict_strtoul
);
204 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol
);
205 STANDARD_PARAM_DEF(uint
, unsigned int, "%u", unsigned long, strict_strtoul
);
206 STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol
);
207 STANDARD_PARAM_DEF(ulong
, unsigned long, "%lu", unsigned long, strict_strtoul
);
209 int param_set_charp(const char *val
, struct kernel_param
*kp
)
212 printk(KERN_ERR
"%s: string parameter expected\n",
217 if (strlen(val
) > 1024) {
218 printk(KERN_ERR
"%s: string parameter too long\n",
223 if (kp
->perm
& KPARAM_KMALLOCED
)
224 kfree(*(char **)kp
->arg
);
226 /* This is a hack. We can't need to strdup in early boot, and we
227 * don't need to; this mangled commandline is preserved. */
228 if (slab_is_available()) {
229 kp
->perm
|= KPARAM_KMALLOCED
;
230 *(char **)kp
->arg
= kstrdup(val
, GFP_KERNEL
);
234 *(const char **)kp
->arg
= val
;
239 int param_get_charp(char *buffer
, struct kernel_param
*kp
)
241 return sprintf(buffer
, "%s", *((char **)kp
->arg
));
244 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 int param_get_bool(char *buffer
, struct kernel_param
*kp
)
263 /* Y and N chosen as being relatively non-coder friendly */
264 return sprintf(buffer
, "%c", (*(int *)kp
->arg
) ? 'Y' : 'N');
267 int param_set_invbool(const char *val
, struct kernel_param
*kp
)
270 struct kernel_param dummy
;
272 dummy
.arg
= &boolval
;
273 ret
= param_set_bool(val
, &dummy
);
275 *(int *)kp
->arg
= !boolval
;
279 int param_get_invbool(char *buffer
, struct kernel_param
*kp
)
281 return sprintf(buffer
, "%c", (*(int *)kp
->arg
) ? 'N' : 'Y');
284 /* We break the rule and mangle the string. */
285 static int param_array(const char *name
,
287 unsigned int min
, unsigned int max
,
288 void *elem
, int elemsize
,
289 int (*set
)(const char *, struct kernel_param
*kp
),
293 struct kernel_param kp
;
296 /* Get the name right for errors. */
300 /* No equals sign? */
302 printk(KERN_ERR
"%s: expects arguments\n", name
);
307 /* We expect a comma-separated list of values. */
312 printk(KERN_ERR
"%s: can only take %i arguments\n",
316 len
= strcspn(val
, ",");
318 /* nul-terminate and parse */
320 ((char *)val
)[len
] = '\0';
328 } while (save
== ',');
331 printk(KERN_ERR
"%s: needs at least %i arguments\n",
338 int param_array_set(const char *val
, struct kernel_param
*kp
)
340 const struct kparam_array
*arr
= kp
->arr
;
341 unsigned int temp_num
;
343 return param_array(kp
->name
, val
, 1, arr
->max
, arr
->elem
,
344 arr
->elemsize
, arr
->set
, arr
->num
?: &temp_num
);
347 int param_array_get(char *buffer
, struct kernel_param
*kp
)
350 const struct kparam_array
*arr
= kp
->arr
;
351 struct kernel_param p
;
354 for (i
= off
= 0; i
< (arr
->num
? *arr
->num
: arr
->max
); i
++) {
357 p
.arg
= arr
->elem
+ arr
->elemsize
* i
;
358 ret
= arr
->get(buffer
+ off
, &p
);
367 int param_set_copystring(const char *val
, struct kernel_param
*kp
)
369 const struct kparam_string
*kps
= kp
->str
;
372 printk(KERN_ERR
"%s: missing param set value\n", kp
->name
);
375 if (strlen(val
)+1 > kps
->maxlen
) {
376 printk(KERN_ERR
"%s: string doesn't fit in %u chars.\n",
377 kp
->name
, kps
->maxlen
-1);
380 strcpy(kps
->string
, val
);
384 int param_get_string(char *buffer
, struct kernel_param
*kp
)
386 const struct kparam_string
*kps
= kp
->str
;
387 return strlcpy(buffer
, kps
->string
, kps
->maxlen
);
390 /* sysfs output in /sys/modules/XYZ/parameters/ */
391 #define to_module_attr(n) container_of(n, struct module_attribute, attr);
392 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj);
394 extern struct kernel_param __start___param
[], __stop___param
[];
396 struct param_attribute
398 struct module_attribute mattr
;
399 struct kernel_param
*param
;
402 struct module_param_attrs
405 struct attribute_group grp
;
406 struct param_attribute attrs
[0];
410 #define to_param_attr(n) container_of(n, struct param_attribute, mattr);
412 static ssize_t
param_attr_show(struct module_attribute
*mattr
,
413 struct module
*mod
, char *buf
)
416 struct param_attribute
*attribute
= to_param_attr(mattr
);
418 if (!attribute
->param
->get
)
421 count
= attribute
->param
->get(buf
, attribute
->param
);
429 /* sysfs always hands a nul-terminated string in buf. We rely on that. */
430 static ssize_t
param_attr_store(struct module_attribute
*mattr
,
431 struct module
*owner
,
432 const char *buf
, size_t len
)
435 struct param_attribute
*attribute
= to_param_attr(mattr
);
437 if (!attribute
->param
->set
)
440 err
= attribute
->param
->set(buf
, attribute
->param
);
447 #ifdef CONFIG_MODULES
450 #define __modinit __init
455 * add_sysfs_param - add a parameter to sysfs
456 * @mk: struct module_kobject
457 * @kparam: the actual parameter definition to add to sysfs
458 * @name: name of parameter
460 * Create a kobject if for a (per-module) parameter if mp NULL, and
461 * create file in sysfs. Returns an error on out of memory. Always cleans up
462 * if there's an error.
464 static __modinit
int add_sysfs_param(struct module_kobject
*mk
,
465 struct kernel_param
*kp
,
468 struct module_param_attrs
*new;
469 struct attribute
**attrs
;
472 /* We don't bother calling this with invisible parameters. */
480 attrs
= mk
->mp
->grp
.attrs
;
484 new = krealloc(mk
->mp
,
485 sizeof(*mk
->mp
) + sizeof(mk
->mp
->attrs
[0]) * (num
+1),
492 attrs
= krealloc(attrs
, sizeof(new->grp
.attrs
[0])*(num
+2), GFP_KERNEL
);
498 /* Sysfs wants everything zeroed. */
499 memset(new, 0, sizeof(*new));
500 memset(&new->attrs
[num
], 0, sizeof(new->attrs
[num
]));
501 memset(&attrs
[num
], 0, sizeof(attrs
[num
]));
502 new->grp
.name
= "parameters";
503 new->grp
.attrs
= attrs
;
505 /* Tack new one on the end. */
506 new->attrs
[num
].param
= kp
;
507 new->attrs
[num
].mattr
.show
= param_attr_show
;
508 new->attrs
[num
].mattr
.store
= param_attr_store
;
509 new->attrs
[num
].mattr
.attr
.name
= (char *)name
;
510 new->attrs
[num
].mattr
.attr
.mode
= kp
->perm
;
513 /* Fix up all the pointers, since krealloc can move us */
514 for (num
= 0; num
< new->num
; num
++)
515 new->grp
.attrs
[num
] = &new->attrs
[num
].mattr
.attr
;
516 new->grp
.attrs
[num
] = NULL
;
528 #ifdef CONFIG_MODULES
529 static void free_module_param_attrs(struct module_kobject
*mk
)
531 kfree(mk
->mp
->grp
.attrs
);
537 * module_param_sysfs_setup - setup sysfs support for one module
539 * @kparam: module parameters (array)
540 * @num_params: number of module parameters
542 * Adds sysfs entries for module parameters under
543 * /sys/module/[mod->name]/parameters/
545 int module_param_sysfs_setup(struct module
*mod
,
546 struct kernel_param
*kparam
,
547 unsigned int num_params
)
552 for (i
= 0; i
< num_params
; i
++) {
553 if (kparam
[i
].perm
== 0)
555 err
= add_sysfs_param(&mod
->mkobj
, &kparam
[i
], kparam
[i
].name
);
564 /* Create the param group. */
565 err
= sysfs_create_group(&mod
->mkobj
.kobj
, &mod
->mkobj
.mp
->grp
);
567 free_module_param_attrs(&mod
->mkobj
);
572 * module_param_sysfs_remove - remove sysfs support for one module
575 * Remove sysfs entries for module parameters and the corresponding
578 void module_param_sysfs_remove(struct module
*mod
)
581 sysfs_remove_group(&mod
->mkobj
.kobj
, &mod
->mkobj
.mp
->grp
);
582 /* We are positive that no one is using any param
583 * attrs at this point. Deallocate immediately. */
584 free_module_param_attrs(&mod
->mkobj
);
589 void destroy_params(const struct kernel_param
*params
, unsigned num
)
593 for (i
= 0; i
< num
; i
++)
594 if (params
[i
].perm
& KPARAM_KMALLOCED
)
595 kfree(*(char **)params
[i
].arg
);
598 static void __init
kernel_add_sysfs_param(const char *name
,
599 struct kernel_param
*kparam
,
600 unsigned int name_skip
)
602 struct module_kobject
*mk
;
603 struct kobject
*kobj
;
606 kobj
= kset_find_obj(module_kset
, name
);
608 /* We already have one. Remove params so we can add more. */
609 mk
= to_module_kobject(kobj
);
610 /* We need to remove it before adding parameters. */
611 sysfs_remove_group(&mk
->kobj
, &mk
->mp
->grp
);
613 mk
= kzalloc(sizeof(struct module_kobject
), GFP_KERNEL
);
616 mk
->mod
= THIS_MODULE
;
617 mk
->kobj
.kset
= module_kset
;
618 err
= kobject_init_and_add(&mk
->kobj
, &module_ktype
, NULL
,
621 kobject_put(&mk
->kobj
);
622 printk(KERN_ERR
"Module '%s' failed add to sysfs, "
623 "error number %d\n", name
, err
);
624 printk(KERN_ERR
"The system will be unstable now.\n");
627 /* So that exit path is even. */
628 kobject_get(&mk
->kobj
);
631 /* These should not fail at boot. */
632 err
= add_sysfs_param(mk
, kparam
, kparam
->name
+ name_skip
);
634 err
= sysfs_create_group(&mk
->kobj
, &mk
->mp
->grp
);
636 kobject_uevent(&mk
->kobj
, KOBJ_ADD
);
637 kobject_put(&mk
->kobj
);
641 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
643 * Add module_parameters to sysfs for "modules" built into the kernel.
645 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
646 * "parameter" name is stored behind a dot in kernel_param->name. So,
647 * extract the "module" name for all built-in kernel_param-eters,
648 * and for all who have the same, call kernel_add_sysfs_param.
650 static void __init
param_sysfs_builtin(void)
652 struct kernel_param
*kp
;
653 unsigned int name_len
;
654 char modname
[MODULE_NAME_LEN
];
656 for (kp
= __start___param
; kp
< __stop___param
; kp
++) {
662 dot
= strchr(kp
->name
, '.');
664 /* This happens for core_param() */
665 strcpy(modname
, "kernel");
668 name_len
= dot
- kp
->name
+ 1;
669 strlcpy(modname
, kp
->name
, name_len
);
671 kernel_add_sysfs_param(modname
, kp
, name_len
);
676 /* module-related sysfs stuff */
678 static ssize_t
module_attr_show(struct kobject
*kobj
,
679 struct attribute
*attr
,
682 struct module_attribute
*attribute
;
683 struct module_kobject
*mk
;
686 attribute
= to_module_attr(attr
);
687 mk
= to_module_kobject(kobj
);
689 if (!attribute
->show
)
692 ret
= attribute
->show(attribute
, mk
->mod
, buf
);
697 static ssize_t
module_attr_store(struct kobject
*kobj
,
698 struct attribute
*attr
,
699 const char *buf
, size_t len
)
701 struct module_attribute
*attribute
;
702 struct module_kobject
*mk
;
705 attribute
= to_module_attr(attr
);
706 mk
= to_module_kobject(kobj
);
708 if (!attribute
->store
)
711 ret
= attribute
->store(attribute
, mk
->mod
, buf
, len
);
716 static struct sysfs_ops module_sysfs_ops
= {
717 .show
= module_attr_show
,
718 .store
= module_attr_store
,
721 static int uevent_filter(struct kset
*kset
, struct kobject
*kobj
)
723 struct kobj_type
*ktype
= get_ktype(kobj
);
725 if (ktype
== &module_ktype
)
730 static struct kset_uevent_ops module_uevent_ops
= {
731 .filter
= uevent_filter
,
734 struct kset
*module_kset
;
735 int module_sysfs_initialized
;
737 struct kobj_type module_ktype
= {
738 .sysfs_ops
= &module_sysfs_ops
,
742 * param_sysfs_init - wrapper for built-in params support
744 static int __init
param_sysfs_init(void)
746 module_kset
= kset_create_and_add("module", &module_uevent_ops
, NULL
);
748 printk(KERN_WARNING
"%s (%d): error creating kset\n",
752 module_sysfs_initialized
= 1;
754 param_sysfs_builtin();
758 subsys_initcall(param_sysfs_init
);
760 #endif /* CONFIG_SYSFS */
762 EXPORT_SYMBOL(param_set_byte
);
763 EXPORT_SYMBOL(param_get_byte
);
764 EXPORT_SYMBOL(param_set_short
);
765 EXPORT_SYMBOL(param_get_short
);
766 EXPORT_SYMBOL(param_set_ushort
);
767 EXPORT_SYMBOL(param_get_ushort
);
768 EXPORT_SYMBOL(param_set_int
);
769 EXPORT_SYMBOL(param_get_int
);
770 EXPORT_SYMBOL(param_set_uint
);
771 EXPORT_SYMBOL(param_get_uint
);
772 EXPORT_SYMBOL(param_set_long
);
773 EXPORT_SYMBOL(param_get_long
);
774 EXPORT_SYMBOL(param_set_ulong
);
775 EXPORT_SYMBOL(param_get_ulong
);
776 EXPORT_SYMBOL(param_set_charp
);
777 EXPORT_SYMBOL(param_get_charp
);
778 EXPORT_SYMBOL(param_set_bool
);
779 EXPORT_SYMBOL(param_get_bool
);
780 EXPORT_SYMBOL(param_set_invbool
);
781 EXPORT_SYMBOL(param_get_invbool
);
782 EXPORT_SYMBOL(param_array_set
);
783 EXPORT_SYMBOL(param_array_get
);
784 EXPORT_SYMBOL(param_set_copystring
);
785 EXPORT_SYMBOL(param_get_string
);