diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/moduleparam.h | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index 6d48831fe7d2..ca74a3402d63 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -130,6 +130,62 @@ __check_old_set_param(int (*oldset)(const char *, struct kernel_param *)) #define module_param(name, type, perm) \ module_param_named(name, name, type, perm) +/** + * kparam_block_sysfs_write - make sure a parameter isn't written via sysfs. + * @name: the name of the parameter + * + * There's no point blocking write on a paramter that isn't writable via sysfs! + */ +#define kparam_block_sysfs_write(name) \ + do { \ + BUG_ON(!(__param_##name.perm & 0222)); \ + __kernel_param_lock(); \ + } while (0) + +/** + * kparam_unblock_sysfs_write - allows sysfs to write to a parameter again. + * @name: the name of the parameter + */ +#define kparam_unblock_sysfs_write(name) \ + do { \ + BUG_ON(!(__param_##name.perm & 0222)); \ + __kernel_param_unlock(); \ + } while (0) + +/** + * kparam_block_sysfs_read - make sure a parameter isn't read via sysfs. + * @name: the name of the parameter + * + * This also blocks sysfs writes. + */ +#define kparam_block_sysfs_read(name) \ + do { \ + BUG_ON(!(__param_##name.perm & 0444)); \ + __kernel_param_lock(); \ + } while (0) + +/** + * kparam_unblock_sysfs_read - allows sysfs to read a parameter again. + * @name: the name of the parameter + */ +#define kparam_unblock_sysfs_read(name) \ + do { \ + BUG_ON(!(__param_##name.perm & 0444)); \ + __kernel_param_unlock(); \ + } while (0) + +#ifdef CONFIG_SYSFS +extern void __kernel_param_lock(void); +extern void __kernel_param_unlock(void); +#else +static inline void __kernel_param_lock(void) +{ +} +static inline void __kernel_param_unlock(void) +{ +} +#endif + #ifndef MODULE /** * core_param - define a historical core kernel parameter. |