diff options
Diffstat (limited to 'include/linux/static_call.h')
| -rw-r--r-- | include/linux/static_call.h | 77 |
1 files changed, 46 insertions, 31 deletions
diff --git a/include/linux/static_call.h b/include/linux/static_call.h index 695da4c9b338..85ecc789f4ff 100644 --- a/include/linux/static_call.h +++ b/include/linux/static_call.h @@ -107,26 +107,10 @@ extern void arch_static_call_transform(void *site, void *tramp, void *func, bool #define STATIC_CALL_TRAMP_ADDR(name) &STATIC_CALL_TRAMP(name) -/* - * __ADDRESSABLE() is used to ensure the key symbol doesn't get stripped from - * the symbol table so that objtool can reference it when it generates the - * .static_call_sites section. - */ -#define __static_call(name) \ -({ \ - __ADDRESSABLE(STATIC_CALL_KEY(name)); \ - &STATIC_CALL_TRAMP(name); \ -}) - #else #define STATIC_CALL_TRAMP_ADDR(name) NULL #endif - -#define DECLARE_STATIC_CALL(name, func) \ - extern struct static_call_key STATIC_CALL_KEY(name); \ - extern typeof(func) STATIC_CALL_TRAMP(name); - #define static_call_update(name, func) \ ({ \ BUILD_BUG_ON(!__same_type(*(func), STATIC_CALL_TRAMP(name))); \ @@ -154,17 +138,25 @@ struct static_call_key { }; }; +/* For finding the key associated with a trampoline */ +struct static_call_tramp_key { + s32 tramp; + s32 key; +}; + extern void __static_call_update(struct static_call_key *key, void *tramp, void *func); extern int static_call_mod_init(struct module *mod); extern int static_call_text_reserved(void *start, void *end); -#define DEFINE_STATIC_CALL(name, _func) \ +extern long __static_call_return0(void); + +#define __DEFINE_STATIC_CALL(name, _func, _func_init) \ DECLARE_STATIC_CALL(name, _func); \ struct static_call_key STATIC_CALL_KEY(name) = { \ - .func = _func, \ + .func = _func_init, \ .type = 1, \ }; \ - ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func) + ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func_init) #define DEFINE_STATIC_CALL_NULL(name, _func) \ DECLARE_STATIC_CALL(name, _func); \ @@ -174,17 +166,23 @@ extern int static_call_text_reserved(void *start, void *end); }; \ ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) -#define static_call(name) __static_call(name) #define static_call_cond(name) (void)__static_call(name) #define EXPORT_STATIC_CALL(name) \ EXPORT_SYMBOL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)) - #define EXPORT_STATIC_CALL_GPL(name) \ EXPORT_SYMBOL_GPL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)) +/* Leave the key unexported, so modules can't change static call targets: */ +#define EXPORT_STATIC_CALL_TRAMP(name) \ + EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)); \ + ARCH_ADD_TRAMP_KEY(name) +#define EXPORT_STATIC_CALL_TRAMP_GPL(name) \ + EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)); \ + ARCH_ADD_TRAMP_KEY(name) + #elif defined(CONFIG_HAVE_STATIC_CALL) static inline int static_call_init(void) { return 0; } @@ -193,12 +191,12 @@ struct static_call_key { void *func; }; -#define DEFINE_STATIC_CALL(name, _func) \ +#define __DEFINE_STATIC_CALL(name, _func, _func_init) \ DECLARE_STATIC_CALL(name, _func); \ struct static_call_key STATIC_CALL_KEY(name) = { \ - .func = _func, \ + .func = _func_init, \ }; \ - ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func) + ARCH_DEFINE_STATIC_CALL_TRAMP(name, _func_init) #define DEFINE_STATIC_CALL_NULL(name, _func) \ DECLARE_STATIC_CALL(name, _func); \ @@ -207,7 +205,6 @@ struct static_call_key { }; \ ARCH_DEFINE_STATIC_CALL_NULL_TRAMP(name) -#define static_call(name) __static_call(name) #define static_call_cond(name) (void)__static_call(name) static inline @@ -224,14 +221,24 @@ static inline int static_call_text_reserved(void *start, void *end) return 0; } +static inline long __static_call_return0(void) +{ + return 0; +} + #define EXPORT_STATIC_CALL(name) \ EXPORT_SYMBOL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)) - #define EXPORT_STATIC_CALL_GPL(name) \ EXPORT_SYMBOL_GPL(STATIC_CALL_KEY(name)); \ EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)) +/* Leave the key unexported, so modules can't change static call targets: */ +#define EXPORT_STATIC_CALL_TRAMP(name) \ + EXPORT_SYMBOL(STATIC_CALL_TRAMP(name)) +#define EXPORT_STATIC_CALL_TRAMP_GPL(name) \ + EXPORT_SYMBOL_GPL(STATIC_CALL_TRAMP(name)) + #else /* Generic implementation */ static inline int static_call_init(void) { return 0; } @@ -240,10 +247,15 @@ struct static_call_key { void *func; }; -#define DEFINE_STATIC_CALL(name, _func) \ +static inline long __static_call_return0(void) +{ + return 0; +} + +#define __DEFINE_STATIC_CALL(name, _func, _func_init) \ DECLARE_STATIC_CALL(name, _func); \ struct static_call_key STATIC_CALL_KEY(name) = { \ - .func = _func, \ + .func = _func_init, \ } #define DEFINE_STATIC_CALL_NULL(name, _func) \ @@ -252,9 +264,6 @@ struct static_call_key { .func = NULL, \ } -#define static_call(name) \ - ((typeof(STATIC_CALL_TRAMP(name))*)(STATIC_CALL_KEY(name).func)) - static inline void __static_call_nop(void) { } /* @@ -295,4 +304,10 @@ static inline int static_call_text_reserved(void *start, void *end) #endif /* CONFIG_HAVE_STATIC_CALL */ +#define DEFINE_STATIC_CALL(name, _func) \ + __DEFINE_STATIC_CALL(name, _func, _func) + +#define DEFINE_STATIC_CALL_RET0(name, _func) \ + __DEFINE_STATIC_CALL(name, _func, __static_call_return0) + #endif /* _LINUX_STATIC_CALL_H */ |