compiler_types.h (12436B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef __LINUX_COMPILER_TYPES_H 3#define __LINUX_COMPILER_TYPES_H 4 5#ifndef __ASSEMBLY__ 6 7#if defined(CONFIG_DEBUG_INFO_BTF) && defined(CONFIG_PAHOLE_HAS_BTF_TAG) && \ 8 __has_attribute(btf_type_tag) 9# define BTF_TYPE_TAG(value) __attribute__((btf_type_tag(#value))) 10#else 11# define BTF_TYPE_TAG(value) /* nothing */ 12#endif 13 14/* sparse defines __CHECKER__; see Documentation/dev-tools/sparse.rst */ 15#ifdef __CHECKER__ 16/* address spaces */ 17# define __kernel __attribute__((address_space(0))) 18# define __user __attribute__((noderef, address_space(__user))) 19# define __iomem __attribute__((noderef, address_space(__iomem))) 20# define __percpu __attribute__((noderef, address_space(__percpu))) 21# define __rcu __attribute__((noderef, address_space(__rcu))) 22static inline void __chk_user_ptr(const volatile void __user *ptr) { } 23static inline void __chk_io_ptr(const volatile void __iomem *ptr) { } 24/* context/locking */ 25# define __must_hold(x) __attribute__((context(x,1,1))) 26# define __acquires(x) __attribute__((context(x,0,1))) 27# define __cond_acquires(x) __attribute__((context(x,0,-1))) 28# define __releases(x) __attribute__((context(x,1,0))) 29# define __acquire(x) __context__(x,1) 30# define __release(x) __context__(x,-1) 31# define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0) 32/* other */ 33# define __force __attribute__((force)) 34# define __nocast __attribute__((nocast)) 35# define __safe __attribute__((safe)) 36# define __private __attribute__((noderef)) 37# define ACCESS_PRIVATE(p, member) (*((typeof((p)->member) __force *) &(p)->member)) 38#else /* __CHECKER__ */ 39/* address spaces */ 40# define __kernel 41# ifdef STRUCTLEAK_PLUGIN 42# define __user __attribute__((user)) 43# else 44# define __user BTF_TYPE_TAG(user) 45# endif 46# define __iomem 47# define __percpu BTF_TYPE_TAG(percpu) 48# define __rcu 49# define __chk_user_ptr(x) (void)0 50# define __chk_io_ptr(x) (void)0 51/* context/locking */ 52# define __must_hold(x) 53# define __acquires(x) 54# define __cond_acquires(x) 55# define __releases(x) 56# define __acquire(x) (void)0 57# define __release(x) (void)0 58# define __cond_lock(x,c) (c) 59/* other */ 60# define __force 61# define __nocast 62# define __safe 63# define __private 64# define ACCESS_PRIVATE(p, member) ((p)->member) 65# define __builtin_warning(x, y...) (1) 66#endif /* __CHECKER__ */ 67 68/* Indirect macros required for expanded argument pasting, eg. __LINE__. */ 69#define ___PASTE(a,b) a##b 70#define __PASTE(a,b) ___PASTE(a,b) 71 72#ifdef __KERNEL__ 73 74/* Attributes */ 75#include <linux/compiler_attributes.h> 76 77/* Builtins */ 78 79/* 80 * __has_builtin is supported on gcc >= 10, clang >= 3 and icc >= 21. 81 * In the meantime, to support gcc < 10, we implement __has_builtin 82 * by hand. 83 */ 84#ifndef __has_builtin 85#define __has_builtin(x) (0) 86#endif 87 88/* Compiler specific macros. */ 89#ifdef __clang__ 90#include <linux/compiler-clang.h> 91#elif defined(__INTEL_COMPILER) 92#include <linux/compiler-intel.h> 93#elif defined(__GNUC__) 94/* The above compilers also define __GNUC__, so order is important here. */ 95#include <linux/compiler-gcc.h> 96#else 97#error "Unknown compiler" 98#endif 99 100/* 101 * Some architectures need to provide custom definitions of macros provided 102 * by linux/compiler-*.h, and can do so using asm/compiler.h. We include that 103 * conditionally rather than using an asm-generic wrapper in order to avoid 104 * build failures if any C compilation, which will include this file via an 105 * -include argument in c_flags, occurs prior to the asm-generic wrappers being 106 * generated. 107 */ 108#ifdef CONFIG_HAVE_ARCH_COMPILER_H 109#include <asm/compiler.h> 110#endif 111 112struct ftrace_branch_data { 113 const char *func; 114 const char *file; 115 unsigned line; 116 union { 117 struct { 118 unsigned long correct; 119 unsigned long incorrect; 120 }; 121 struct { 122 unsigned long miss; 123 unsigned long hit; 124 }; 125 unsigned long miss_hit[2]; 126 }; 127}; 128 129struct ftrace_likely_data { 130 struct ftrace_branch_data data; 131 unsigned long constant; 132}; 133 134#if defined(CC_USING_HOTPATCH) 135#define notrace __attribute__((hotpatch(0, 0))) 136#elif defined(CC_USING_PATCHABLE_FUNCTION_ENTRY) 137#define notrace __attribute__((patchable_function_entry(0, 0))) 138#else 139#define notrace __attribute__((__no_instrument_function__)) 140#endif 141 142/* 143 * it doesn't make sense on ARM (currently the only user of __naked) 144 * to trace naked functions because then mcount is called without 145 * stack and frame pointer being set up and there is no chance to 146 * restore the lr register to the value before mcount was called. 147 */ 148#define __naked __attribute__((__naked__)) notrace 149 150/* 151 * Prefer gnu_inline, so that extern inline functions do not emit an 152 * externally visible function. This makes extern inline behave as per gnu89 153 * semantics rather than c99. This prevents multiple symbol definition errors 154 * of extern inline functions at link time. 155 * A lot of inline functions can cause havoc with function tracing. 156 */ 157#define inline inline __gnu_inline __inline_maybe_unused notrace 158 159/* 160 * gcc provides both __inline__ and __inline as alternate spellings of 161 * the inline keyword, though the latter is undocumented. New kernel 162 * code should only use the inline spelling, but some existing code 163 * uses __inline__. Since we #define inline above, to ensure 164 * __inline__ has the same semantics, we need this #define. 165 * 166 * However, the spelling __inline is strictly reserved for referring 167 * to the bare keyword. 168 */ 169#define __inline__ inline 170 171/* 172 * GCC does not warn about unused static inline functions for -Wunused-function. 173 * Suppress the warning in clang as well by using __maybe_unused, but enable it 174 * for W=1 build. This will allow clang to find unused functions. Remove the 175 * __inline_maybe_unused entirely after fixing most of -Wunused-function warnings. 176 */ 177#ifdef KBUILD_EXTRA_WARN1 178#define __inline_maybe_unused 179#else 180#define __inline_maybe_unused __maybe_unused 181#endif 182 183/* 184 * Rather then using noinline to prevent stack consumption, use 185 * noinline_for_stack instead. For documentation reasons. 186 */ 187#define noinline_for_stack noinline 188 189/* 190 * Sanitizer helper attributes: Because using __always_inline and 191 * __no_sanitize_* conflict, provide helper attributes that will either expand 192 * to __no_sanitize_* in compilation units where instrumentation is enabled 193 * (__SANITIZE_*__), or __always_inline in compilation units without 194 * instrumentation (__SANITIZE_*__ undefined). 195 */ 196#ifdef __SANITIZE_ADDRESS__ 197/* 198 * We can't declare function 'inline' because __no_sanitize_address conflicts 199 * with inlining. Attempt to inline it may cause a build failure. 200 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368 201 * '__maybe_unused' allows us to avoid defined-but-not-used warnings. 202 */ 203# define __no_kasan_or_inline __no_sanitize_address notrace __maybe_unused 204# define __no_sanitize_or_inline __no_kasan_or_inline 205#else 206# define __no_kasan_or_inline __always_inline 207#endif 208 209#ifdef __SANITIZE_THREAD__ 210/* 211 * Clang still emits instrumentation for __tsan_func_{entry,exit}() and builtin 212 * atomics even with __no_sanitize_thread (to avoid false positives in userspace 213 * ThreadSanitizer). The kernel's requirements are stricter and we really do not 214 * want any instrumentation with __no_kcsan. 215 * 216 * Therefore we add __disable_sanitizer_instrumentation where available to 217 * disable all instrumentation. See Kconfig.kcsan where this is mandatory. 218 */ 219# define __no_kcsan __no_sanitize_thread __disable_sanitizer_instrumentation 220# define __no_sanitize_or_inline __no_kcsan notrace __maybe_unused 221#else 222# define __no_kcsan 223#endif 224 225#ifndef __no_sanitize_or_inline 226#define __no_sanitize_or_inline __always_inline 227#endif 228 229/* Section for code which can't be instrumented at all */ 230#define noinstr \ 231 noinline notrace __attribute((__section__(".noinstr.text"))) \ 232 __no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage 233 234#endif /* __KERNEL__ */ 235 236#endif /* __ASSEMBLY__ */ 237 238/* 239 * The below symbols may be defined for one or more, but not ALL, of the above 240 * compilers. We don't consider that to be an error, so set them to nothing. 241 * For example, some of them are for compiler specific plugins. 242 */ 243#ifndef __latent_entropy 244# define __latent_entropy 245#endif 246 247#if defined(RANDSTRUCT) && !defined(__CHECKER__) 248# define __randomize_layout __designated_init __attribute__((randomize_layout)) 249# define __no_randomize_layout __attribute__((no_randomize_layout)) 250/* This anon struct can add padding, so only enable it under randstruct. */ 251# define randomized_struct_fields_start struct { 252# define randomized_struct_fields_end } __randomize_layout; 253#else 254# define __randomize_layout __designated_init 255# define __no_randomize_layout 256# define randomized_struct_fields_start 257# define randomized_struct_fields_end 258#endif 259 260#ifndef __noscs 261# define __noscs 262#endif 263 264#ifndef __nocfi 265# define __nocfi 266#endif 267 268#ifndef __cficanonical 269# define __cficanonical 270#endif 271 272/* 273 * Any place that could be marked with the "alloc_size" attribute is also 274 * a place to be marked with the "malloc" attribute. Do this as part of the 275 * __alloc_size macro to avoid redundant attributes and to avoid missing a 276 * __malloc marking. 277 */ 278#ifdef __alloc_size__ 279# define __alloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) __malloc 280#else 281# define __alloc_size(x, ...) __malloc 282#endif 283 284#ifndef asm_volatile_goto 285#define asm_volatile_goto(x...) asm goto(x) 286#endif 287 288#ifdef CONFIG_CC_HAS_ASM_INLINE 289#define asm_inline asm __inline 290#else 291#define asm_inline asm 292#endif 293 294/* Are two types/vars the same type (ignoring qualifiers)? */ 295#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) 296 297/* 298 * __unqual_scalar_typeof(x) - Declare an unqualified scalar type, leaving 299 * non-scalar types unchanged. 300 */ 301/* 302 * Prefer C11 _Generic for better compile-times and simpler code. Note: 'char' 303 * is not type-compatible with 'signed char', and we define a separate case. 304 */ 305#define __scalar_type_to_expr_cases(type) \ 306 unsigned type: (unsigned type)0, \ 307 signed type: (signed type)0 308 309#define __unqual_scalar_typeof(x) typeof( \ 310 _Generic((x), \ 311 char: (char)0, \ 312 __scalar_type_to_expr_cases(char), \ 313 __scalar_type_to_expr_cases(short), \ 314 __scalar_type_to_expr_cases(int), \ 315 __scalar_type_to_expr_cases(long), \ 316 __scalar_type_to_expr_cases(long long), \ 317 default: (x))) 318 319/* Is this type a native word size -- useful for atomic operations */ 320#define __native_word(t) \ 321 (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \ 322 sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) 323 324#ifdef __OPTIMIZE__ 325# define __compiletime_assert(condition, msg, prefix, suffix) \ 326 do { \ 327 /* \ 328 * __noreturn is needed to give the compiler enough \ 329 * information to avoid certain possibly-uninitialized \ 330 * warnings (regardless of the build failing). \ 331 */ \ 332 __noreturn extern void prefix ## suffix(void) \ 333 __compiletime_error(msg); \ 334 if (!(condition)) \ 335 prefix ## suffix(); \ 336 } while (0) 337#else 338# define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0) 339#endif 340 341#define _compiletime_assert(condition, msg, prefix, suffix) \ 342 __compiletime_assert(condition, msg, prefix, suffix) 343 344/** 345 * compiletime_assert - break build and emit msg if condition is false 346 * @condition: a compile-time constant condition to check 347 * @msg: a message to emit if condition is false 348 * 349 * In tradition of POSIX assert, this macro will break the build if the 350 * supplied condition is *false*, emitting the supplied error message if the 351 * compiler has support to do so. 352 */ 353#define compiletime_assert(condition, msg) \ 354 _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) 355 356#define compiletime_assert_atomic_type(t) \ 357 compiletime_assert(__native_word(t), \ 358 "Need native word sized stores/loads for atomicity.") 359 360/* Helpers for emitting diagnostics in pragmas. */ 361#ifndef __diag 362#define __diag(string) 363#endif 364 365#ifndef __diag_GCC 366#define __diag_GCC(version, severity, string) 367#endif 368 369#define __diag_push() __diag(push) 370#define __diag_pop() __diag(pop) 371 372#define __diag_ignore(compiler, version, option, comment) \ 373 __diag_ ## compiler(version, ignore, option) 374#define __diag_warn(compiler, version, option, comment) \ 375 __diag_ ## compiler(version, warn, option) 376#define __diag_error(compiler, version, option, comment) \ 377 __diag_ ## compiler(version, error, option) 378 379#ifndef __diag_ignore_all 380#define __diag_ignore_all(option, comment) 381#endif 382 383#endif /* __LINUX_COMPILER_TYPES_H */