From fddd520122953550ec2c8b60e7ca0d0f0d115d97 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 12 Jun 2009 21:46:57 -0600 Subject: [PATCH] module_param: allow 'bool' module_params to be bool, not just int. Impact: API cleanup For historical reasons, 'bool' parameters must be an int, not a bool. But there are around 600 users, so a conversion seems like useless churn. So we use __same_type() to distinguish, and handle both cases. Signed-off-by: Rusty Russell --- include/linux/moduleparam.h | 32 +++++++++++++++++++++++--------- kernel/params.c | 33 ++++++++++++++++++++++++++------- 2 files changed, 49 insertions(+), 16 deletions(-) diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index 009a5f768768..6547c3cdbc4c 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -38,6 +38,7 @@ typedef int (*param_get_fn)(char *buffer, struct kernel_param *kp); /* Flag bits for kernel_param.flags */ #define KPARAM_KMALLOCED 1 +#define KPARAM_ISBOOL 2 struct kernel_param { const char *name; @@ -83,7 +84,7 @@ struct kparam_array parameters. perm sets the visibility in sysfs: 000 means it's not there, read bits mean it's readable, write bits mean it's writable. */ -#define __module_param_call(prefix, name, set, get, arg, perm) \ +#define __module_param_call(prefix, name, set, get, arg, isbool, perm) \ /* Default value instead of permissions? */ \ static int __param_perm_check_##name __attribute__((unused)) = \ BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2)) \ @@ -92,10 +93,13 @@ struct kparam_array static struct kernel_param __moduleparam_const __param_##name \ __used \ __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \ - = { __param_str_##name, perm, 0, set, get, { arg } } + = { __param_str_##name, perm, isbool ? KPARAM_ISBOOL : 0, \ + set, get, { arg } } #define module_param_call(name, set, get, arg, perm) \ - __module_param_call(MODULE_PARAM_PREFIX, name, set, get, arg, perm) + __module_param_call(MODULE_PARAM_PREFIX, \ + name, set, get, arg, \ + __same_type(*(arg), bool), perm) /* Helper functions: type is byte, short, ushort, int, uint, long, ulong, charp, bool or invbool, or XXX if you define param_get_XXX, @@ -124,15 +128,16 @@ struct kparam_array #define core_param(name, var, type, perm) \ param_check_##type(name, &(var)); \ __module_param_call("", name, param_set_##type, param_get_##type, \ - &var, perm) + &var, __same_type(var, bool), perm) #endif /* !MODULE */ /* Actually copy string: maxlen param is usually sizeof(string). */ #define module_param_string(name, string, len, perm) \ static const struct kparam_string __param_string_##name \ = { len, string }; \ - module_param_call(name, param_set_copystring, param_get_string, \ - .str = &__param_string_##name, perm); \ + __module_param_call(MODULE_PARAM_PREFIX, name, \ + param_set_copystring, param_get_string, \ + .str = &__param_string_##name, 0, perm); \ __MODULE_PARM_TYPE(name, "string") /* Called on module insert or kernel boot */ @@ -190,9 +195,16 @@ extern int param_set_charp(const char *val, struct kernel_param *kp); extern int param_get_charp(char *buffer, struct kernel_param *kp); #define param_check_charp(name, p) __param_check(name, p, char *) +/* For historical reasons "bool" parameters can be (unsigned) "int". */ extern int param_set_bool(const char *val, struct kernel_param *kp); extern int param_get_bool(char *buffer, struct kernel_param *kp); -#define param_check_bool(name, p) __param_check(name, p, int) +#define param_check_bool(name, p) \ + static inline void __check_##name(void) \ + { \ + BUILD_BUG_ON(!__same_type(*(p), bool) && \ + !__same_type(*(p), unsigned int) && \ + !__same_type(*(p), int)); \ + } extern int param_set_invbool(const char *val, struct kernel_param *kp); extern int param_get_invbool(char *buffer, struct kernel_param *kp); @@ -203,8 +215,10 @@ extern int param_get_invbool(char *buffer, struct kernel_param *kp); static const struct kparam_array __param_arr_##name \ = { ARRAY_SIZE(array), nump, param_set_##type, param_get_##type,\ sizeof(array[0]), array }; \ - module_param_call(name, param_array_set, param_array_get, \ - .arr = &__param_arr_##name, perm); \ + __module_param_call(MODULE_PARAM_PREFIX, name, \ + param_array_set, param_array_get, \ + .arr = &__param_arr_##name, \ + __same_type(array[0], bool), perm); \ __MODULE_PARM_TYPE(name, "array of " #type) #define module_param_array(name, type, nump, perm) \ diff --git a/kernel/params.c b/kernel/params.c index b4660dc13dbc..7f6912ced2ba 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -238,35 +238,54 @@ int param_get_charp(char *buffer, struct kernel_param *kp) return sprintf(buffer, "%s", *((char **)kp->arg)); } +/* Actually could be a bool or an int, for historical reasons. */ int param_set_bool(const char *val, struct kernel_param *kp) { + bool v; + /* No equals means "set"... */ if (!val) val = "1"; /* One of =[yYnN01] */ switch (val[0]) { case 'y': case 'Y': case '1': - *(int *)kp->arg = 1; - return 0; + v = true; + break; case 'n': case 'N': case '0': - *(int *)kp->arg = 0; - return 0; + v = false; + break; + default: + return -EINVAL; } - return -EINVAL; + + if (kp->flags & KPARAM_ISBOOL) + *(bool *)kp->arg = v; + else + *(int *)kp->arg = v; + return 0; } int param_get_bool(char *buffer, struct kernel_param *kp) { + bool val; + if (kp->flags & KPARAM_ISBOOL) + val = *(bool *)kp->arg; + else + val = *(int *)kp->arg; + /* Y and N chosen as being relatively non-coder friendly */ - return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'Y' : 'N'); + return sprintf(buffer, "%c", val ? 'Y' : 'N'); } +/* This one must be bool. */ int param_set_invbool(const char *val, struct kernel_param *kp) { - int boolval, ret; + int ret; + bool boolval; struct kernel_param dummy; dummy.arg = &boolval; + dummy.flags = KPARAM_ISBOOL; ret = param_set_bool(val, &dummy); if (ret == 0) *(bool *)kp->arg = !boolval; -- GitLab