diff options
Diffstat (limited to 'include/linux/bug.h')
-rw-r--r-- | include/linux/bug.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/include/linux/bug.h b/include/linux/bug.h new file mode 100644 index 00000000..72961c39 --- /dev/null +++ b/include/linux/bug.h @@ -0,0 +1,99 @@ +#ifndef _LINUX_BUG_H +#define _LINUX_BUG_H + +#include <asm/bug.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) +#define BUILD_BUG_ON_ZERO(e) (0) +#define BUILD_BUG_ON_NULL(e) ((void*)0) +#define BUILD_BUG_ON(condition) +#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 - 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 + * 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 (eg. not arguments + * to inline functions). So as a fallback we use the optimizer; if it can't + * prove the condition is false, it will cause a link error on the undefined + * "__build_bug_on_failed". This error message can be harder to track down + * though, hence the two different methods. + */ +#ifndef __OPTIMIZE__ +#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)])) +#else +extern int __build_bug_on_failed; +#define BUILD_BUG_ON(condition) \ + do { \ + ((void)sizeof(char[1 - 2*!!(condition)])); \ + if (condition) __build_bug_on_failed = 1; \ + } while(0) +#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() \ + do { \ + extern void __build_bug_failed(void) \ + __linktime_error("BUILD_BUG failed"); \ + __build_bug_failed(); \ + } while (0) + +#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 */ |