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Diffstat (limited to 'include/linux/compiler_types.h')
| -rw-r--r-- | include/linux/compiler_types.h | 386 |
1 files changed, 386 insertions, 0 deletions
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h new file mode 100644 index 000000000..eb0466236 --- /dev/null +++ b/include/linux/compiler_types.h @@ -0,0 +1,386 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __LINUX_COMPILER_TYPES_H +#define __LINUX_COMPILER_TYPES_H + +#ifndef __ASSEMBLY__ + +/* + * Skipped when running bindgen due to a libclang issue; + * see https://github.com/rust-lang/rust-bindgen/issues/2244. + */ +#if defined(CONFIG_DEBUG_INFO_BTF) && defined(CONFIG_PAHOLE_HAS_BTF_TAG) && \ + __has_attribute(btf_type_tag) && !defined(__BINDGEN__) +# define BTF_TYPE_TAG(value) __attribute__((btf_type_tag(#value))) +#else +# define BTF_TYPE_TAG(value) /* nothing */ +#endif + +/* sparse defines __CHECKER__; see Documentation/dev-tools/sparse.rst */ +#ifdef __CHECKER__ +/* address spaces */ +# define __kernel __attribute__((address_space(0))) +# define __user __attribute__((noderef, address_space(__user))) +# define __iomem __attribute__((noderef, address_space(__iomem))) +# define __percpu __attribute__((noderef, address_space(__percpu))) +# define __rcu __attribute__((noderef, address_space(__rcu))) +static inline void __chk_user_ptr(const volatile void __user *ptr) { } +static inline void __chk_io_ptr(const volatile void __iomem *ptr) { } +/* context/locking */ +# define __must_hold(x) __attribute__((context(x,1,1))) +# define __acquires(x) __attribute__((context(x,0,1))) +# define __cond_acquires(x) __attribute__((context(x,0,-1))) +# define __releases(x) __attribute__((context(x,1,0))) +# define __acquire(x) __context__(x,1) +# define __release(x) __context__(x,-1) +# define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0) +/* other */ +# define __force __attribute__((force)) +# define __nocast __attribute__((nocast)) +# define __safe __attribute__((safe)) +# define __private __attribute__((noderef)) +# define ACCESS_PRIVATE(p, member) (*((typeof((p)->member) __force *) &(p)->member)) +#else /* __CHECKER__ */ +/* address spaces */ +# define __kernel +# ifdef STRUCTLEAK_PLUGIN +# define __user __attribute__((user)) +# else +# define __user BTF_TYPE_TAG(user) +# endif +# define __iomem +# define __percpu BTF_TYPE_TAG(percpu) +# define __rcu +# define __chk_user_ptr(x) (void)0 +# define __chk_io_ptr(x) (void)0 +/* context/locking */ +# define __must_hold(x) +# define __acquires(x) +# define __cond_acquires(x) +# define __releases(x) +# define __acquire(x) (void)0 +# define __release(x) (void)0 +# define __cond_lock(x,c) (c) +/* other */ +# define __force +# define __nocast +# define __safe +# define __private +# define ACCESS_PRIVATE(p, member) ((p)->member) +# define __builtin_warning(x, y...) (1) +#endif /* __CHECKER__ */ + +/* Indirect macros required for expanded argument pasting, eg. __LINE__. */ +#define ___PASTE(a,b) a##b +#define __PASTE(a,b) ___PASTE(a,b) + +#ifdef __KERNEL__ + +/* Attributes */ +#include <linux/compiler_attributes.h> + +/* Builtins */ + +/* + * __has_builtin is supported on gcc >= 10, clang >= 3 and icc >= 21. + * In the meantime, to support gcc < 10, we implement __has_builtin + * by hand. + */ +#ifndef __has_builtin +#define __has_builtin(x) (0) +#endif + +/* Compiler specific macros. */ +#ifdef __clang__ +#include <linux/compiler-clang.h> +#elif defined(__INTEL_COMPILER) +#include <linux/compiler-intel.h> +#elif defined(__GNUC__) +/* The above compilers also define __GNUC__, so order is important here. */ +#include <linux/compiler-gcc.h> +#else +#error "Unknown compiler" +#endif + +/* + * Some architectures need to provide custom definitions of macros provided + * by linux/compiler-*.h, and can do so using asm/compiler.h. We include that + * conditionally rather than using an asm-generic wrapper in order to avoid + * build failures if any C compilation, which will include this file via an + * -include argument in c_flags, occurs prior to the asm-generic wrappers being + * generated. + */ +#ifdef CONFIG_HAVE_ARCH_COMPILER_H +#include <asm/compiler.h> +#endif + +struct ftrace_branch_data { + const char *func; + const char *file; + unsigned line; + union { + struct { + unsigned long correct; + unsigned long incorrect; + }; + struct { + unsigned long miss; + unsigned long hit; + }; + unsigned long miss_hit[2]; + }; +}; + +struct ftrace_likely_data { + struct ftrace_branch_data data; + unsigned long constant; +}; + +#if defined(CC_USING_HOTPATCH) +#define notrace __attribute__((hotpatch(0, 0))) +#elif defined(CC_USING_PATCHABLE_FUNCTION_ENTRY) +#define notrace __attribute__((patchable_function_entry(0, 0))) +#else +#define notrace __attribute__((__no_instrument_function__)) +#endif + +/* + * it doesn't make sense on ARM (currently the only user of __naked) + * to trace naked functions because then mcount is called without + * stack and frame pointer being set up and there is no chance to + * restore the lr register to the value before mcount was called. + */ +#define __naked __attribute__((__naked__)) notrace + +/* + * Prefer gnu_inline, so that extern inline functions do not emit an + * externally visible function. This makes extern inline behave as per gnu89 + * semantics rather than c99. This prevents multiple symbol definition errors + * of extern inline functions at link time. + * A lot of inline functions can cause havoc with function tracing. + */ +#define inline inline __gnu_inline __inline_maybe_unused notrace + +/* + * gcc provides both __inline__ and __inline as alternate spellings of + * the inline keyword, though the latter is undocumented. New kernel + * code should only use the inline spelling, but some existing code + * uses __inline__. Since we #define inline above, to ensure + * __inline__ has the same semantics, we need this #define. + * + * However, the spelling __inline is strictly reserved for referring + * to the bare keyword. + */ +#define __inline__ inline + +/* + * GCC does not warn about unused static inline functions for -Wunused-function. + * Suppress the warning in clang as well by using __maybe_unused, but enable it + * for W=1 build. This will allow clang to find unused functions. Remove the + * __inline_maybe_unused entirely after fixing most of -Wunused-function warnings. + */ +#ifdef KBUILD_EXTRA_WARN1 +#define __inline_maybe_unused +#else +#define __inline_maybe_unused __maybe_unused +#endif + +/* + * Rather then using noinline to prevent stack consumption, use + * noinline_for_stack instead. For documentation reasons. + */ +#define noinline_for_stack noinline + +/* + * Sanitizer helper attributes: Because using __always_inline and + * __no_sanitize_* conflict, provide helper attributes that will either expand + * to __no_sanitize_* in compilation units where instrumentation is enabled + * (__SANITIZE_*__), or __always_inline in compilation units without + * instrumentation (__SANITIZE_*__ undefined). + */ +#ifdef __SANITIZE_ADDRESS__ +/* + * We can't declare function 'inline' because __no_sanitize_address conflicts + * with inlining. Attempt to inline it may cause a build failure. + * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368 + * '__maybe_unused' allows us to avoid defined-but-not-used warnings. + */ +# define __no_kasan_or_inline __no_sanitize_address notrace __maybe_unused +# define __no_sanitize_or_inline __no_kasan_or_inline +#else +# define __no_kasan_or_inline __always_inline +#endif + +#ifdef __SANITIZE_THREAD__ +/* + * Clang still emits instrumentation for __tsan_func_{entry,exit}() and builtin + * atomics even with __no_sanitize_thread (to avoid false positives in userspace + * ThreadSanitizer). The kernel's requirements are stricter and we really do not + * want any instrumentation with __no_kcsan. + * + * Therefore we add __disable_sanitizer_instrumentation where available to + * disable all instrumentation. See Kconfig.kcsan where this is mandatory. + */ +# define __no_kcsan __no_sanitize_thread __disable_sanitizer_instrumentation +# define __no_sanitize_or_inline __no_kcsan notrace __maybe_unused +#else +# define __no_kcsan +#endif + +#ifndef __no_sanitize_or_inline +#define __no_sanitize_or_inline __always_inline +#endif + +/* Section for code which can't be instrumented at all */ +#define noinstr \ + noinline notrace __attribute((__section__(".noinstr.text"))) \ + __no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage \ + __no_sanitize_memory + +#endif /* __KERNEL__ */ + +#endif /* __ASSEMBLY__ */ + +/* + * The below symbols may be defined for one or more, but not ALL, of the above + * compilers. We don't consider that to be an error, so set them to nothing. + * For example, some of them are for compiler specific plugins. + */ +#ifndef __latent_entropy +# define __latent_entropy +#endif + +#if defined(RANDSTRUCT) && !defined(__CHECKER__) +# define __randomize_layout __designated_init __attribute__((randomize_layout)) +# define __no_randomize_layout __attribute__((no_randomize_layout)) +/* This anon struct can add padding, so only enable it under randstruct. */ +# define randomized_struct_fields_start struct { +# define randomized_struct_fields_end } __randomize_layout; +#else +# define __randomize_layout __designated_init +# define __no_randomize_layout +# define randomized_struct_fields_start +# define randomized_struct_fields_end +#endif + +#ifndef __noscs +# define __noscs +#endif + +#ifndef __nocfi +# define __nocfi +#endif + +/* + * Any place that could be marked with the "alloc_size" attribute is also + * a place to be marked with the "malloc" attribute, except those that may + * be performing a _reallocation_, as that may alias the existing pointer. + * For these, use __realloc_size(). + */ +#ifdef __alloc_size__ +# define __alloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) __malloc +# define __realloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) +#else +# define __alloc_size(x, ...) __malloc +# define __realloc_size(x, ...) +#endif + +#ifndef asm_volatile_goto +#define asm_volatile_goto(x...) asm goto(x) +#endif + +#ifdef CONFIG_CC_HAS_ASM_INLINE +#define asm_inline asm __inline +#else +#define asm_inline asm +#endif + +/* Are two types/vars the same type (ignoring qualifiers)? */ +#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) + +/* + * __unqual_scalar_typeof(x) - Declare an unqualified scalar type, leaving + * non-scalar types unchanged. + */ +/* + * Prefer C11 _Generic for better compile-times and simpler code. Note: 'char' + * is not type-compatible with 'signed char', and we define a separate case. + */ +#define __scalar_type_to_expr_cases(type) \ + unsigned type: (unsigned type)0, \ + signed type: (signed type)0 + +#define __unqual_scalar_typeof(x) typeof( \ + _Generic((x), \ + char: (char)0, \ + __scalar_type_to_expr_cases(char), \ + __scalar_type_to_expr_cases(short), \ + __scalar_type_to_expr_cases(int), \ + __scalar_type_to_expr_cases(long), \ + __scalar_type_to_expr_cases(long long), \ + default: (x))) + +/* Is this type a native word size -- useful for atomic operations */ +#define __native_word(t) \ + (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \ + sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) + +#ifdef __OPTIMIZE__ +# define __compiletime_assert(condition, msg, prefix, suffix) \ + do { \ + /* \ + * __noreturn is needed to give the compiler enough \ + * information to avoid certain possibly-uninitialized \ + * warnings (regardless of the build failing). \ + */ \ + __noreturn extern void prefix ## suffix(void) \ + __compiletime_error(msg); \ + if (!(condition)) \ + prefix ## suffix(); \ + } while (0) +#else +# define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0) +#endif + +#define _compiletime_assert(condition, msg, prefix, suffix) \ + __compiletime_assert(condition, msg, prefix, suffix) + +/** + * compiletime_assert - break build and emit msg if condition is false + * @condition: a compile-time constant condition to check + * @msg: a message to emit if condition is false + * + * In tradition of POSIX assert, this macro will break the build if the + * supplied condition is *false*, emitting the supplied error message if the + * compiler has support to do so. + */ +#define compiletime_assert(condition, msg) \ + _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) + +#define compiletime_assert_atomic_type(t) \ + compiletime_assert(__native_word(t), \ + "Need native word sized stores/loads for atomicity.") + +/* Helpers for emitting diagnostics in pragmas. */ +#ifndef __diag +#define __diag(string) +#endif + +#ifndef __diag_GCC +#define __diag_GCC(version, severity, string) +#endif + +#define __diag_push() __diag(push) +#define __diag_pop() __diag(pop) + +#define __diag_ignore(compiler, version, option, comment) \ + __diag_ ## compiler(version, ignore, option) +#define __diag_warn(compiler, version, option, comment) \ + __diag_ ## compiler(version, warn, option) +#define __diag_error(compiler, version, option, comment) \ + __diag_ ## compiler(version, error, option) + +#ifndef __diag_ignore_all +#define __diag_ignore_all(option, comment) +#endif + +#endif /* __LINUX_COMPILER_TYPES_H */ |