diff options
Diffstat (limited to 'kernel/include/linux/bug.h')
-rw-r--r-- | kernel/include/linux/bug.h | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/kernel/include/linux/bug.h b/kernel/include/linux/bug.h new file mode 100644 index 000000000..7f4818673 --- /dev/null +++ b/kernel/include/linux/bug.h @@ -0,0 +1,112 @@ +#ifndef _LINUX_BUG_H +#define _LINUX_BUG_H + +#include <asm/bug.h> +#include <linux/compiler.h> + +enum bug_trap_type { + BUG_TRAP_TYPE_NONE = 0, + BUG_TRAP_TYPE_WARN = 1, + BUG_TRAP_TYPE_BUG = 2, +}; + +struct pt_regs; + +#ifdef __CHECKER__ +#define BUILD_BUG_ON_NOT_POWER_OF_2(n) (0) +#define BUILD_BUG_ON_ZERO(e) (0) +#define BUILD_BUG_ON_NULL(e) ((void*)0) +#define BUILD_BUG_ON_INVALID(e) (0) +#define BUILD_BUG_ON_MSG(cond, msg) (0) +#define BUILD_BUG_ON(condition) (0) +#define BUILD_BUG() (0) +#else /* __CHECKER__ */ + +/* Force a compilation error if a constant expression is not a power of 2 */ +#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \ + BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0)) + +/* Force a compilation error if condition is true, but also produce a + result (of value 0 and type size_t), so the expression can be used + e.g. in a structure initializer (or where-ever else comma expressions + aren't permitted). */ +#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); })) +#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); })) + +/* + * BUILD_BUG_ON_INVALID() permits the compiler to check the validity of the + * expression but avoids the generation of any code, even if that expression + * has side-effects. + */ +#define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e)))) + +/** + * BUILD_BUG_ON_MSG - break compile if a condition is true & emit supplied + * error message. + * @condition: the condition which the compiler should know is false. + * + * See BUILD_BUG_ON for description. + */ +#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) + +/** + * BUILD_BUG_ON - break compile if a condition is true. + * @condition: the condition which the compiler should know is false. + * + * If you have some code which relies on certain constants being equal, or + * some other compile-time-evaluated condition, you should use BUILD_BUG_ON to + * detect if someone changes it. + * + * The implementation uses gcc's reluctance to create a negative array, but gcc + * (as of 4.4) only emits that error for obvious cases (e.g. not arguments to + * inline functions). Luckily, in 4.3 they added the "error" function + * attribute just for this type of case. Thus, we use a negative sized array + * (should always create an error on gcc versions older than 4.4) and then call + * an undefined function with the error attribute (should always create an + * error on gcc 4.3 and later). If for some reason, neither creates a + * compile-time error, we'll still have a link-time error, which is harder to + * track down. + */ +#ifndef __OPTIMIZE__ +#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)])) +#else +#define BUILD_BUG_ON(condition) \ + BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) +#endif + +/** + * BUILD_BUG - break compile if used. + * + * If you have some code that you expect the compiler to eliminate at + * build time, you should use BUILD_BUG to detect if it is + * unexpectedly used. + */ +#define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed") + +#endif /* __CHECKER__ */ + +#ifdef CONFIG_GENERIC_BUG +#include <asm-generic/bug.h> + +static inline int is_warning_bug(const struct bug_entry *bug) +{ + return bug->flags & BUGFLAG_WARNING; +} + +const struct bug_entry *find_bug(unsigned long bugaddr); + +enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs); + +/* These are defined by the architecture */ +int is_valid_bugaddr(unsigned long addr); + +#else /* !CONFIG_GENERIC_BUG */ + +static inline enum bug_trap_type report_bug(unsigned long bug_addr, + struct pt_regs *regs) +{ + return BUG_TRAP_TYPE_BUG; +} + +#endif /* CONFIG_GENERIC_BUG */ +#endif /* _LINUX_BUG_H */ |