#ifndef _LINUX_BUG_H #define _LINUX_BUG_H #include #include 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_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) #define MAYBE_BUILD_BUG_ON(cond) (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) & ((n) - 1)) != 0) #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") #define MAYBE_BUILD_BUG_ON(cond) \ do { \ if (__builtin_constant_p((cond))) \ BUILD_BUG_ON(cond); \ else \ BUG_ON(cond); \ } while (0) #endif /* __CHECKER__ */ #ifdef CONFIG_GENERIC_BUG #include static inline int is_warning_bug(const struct bug_entry *bug) { return bug->flags & BUGFLAG_WARNING; } 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 */ /* * Since detected data corruption should stop operation on the affected * structures. Return value must be checked and sanely acted on by caller. */ static inline __must_check bool check_data_corruption(bool v) { return v; } #define CHECK_DATA_CORRUPTION(condition, fmt, ...) \ check_data_corruption(({ \ bool corruption = unlikely(condition); \ if (corruption) { \ if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \ pr_err(fmt, ##__VA_ARGS__); \ BUG(); \ } else \ WARN(1, fmt, ##__VA_ARGS__); \ } \ corruption; \ })) #endif /* _LINUX_BUG_H */