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 /* 8 * Skipped when running bindgen due to a libclang issue; 9 * see https://github.com/rust-lang/rust-bindgen/issues/2244. 10 */ 11 #if defined(CONFIG_DEBUG_INFO_BTF) && defined(CONFIG_PAHOLE_HAS_BTF_TAG) && \ 12 __has_attribute(btf_type_tag) && !defined(__BINDGEN__) 13 # define BTF_TYPE_TAG(value) __attribute__((btf_type_tag(#value))) 14 #else 15 # define BTF_TYPE_TAG(value) /* nothing */ 16 #endif 17 18 /* sparse defines __CHECKER__; see Documentation/dev-tools/sparse.rst */ 19 #ifdef __CHECKER__ 20 /* address spaces */ 21 # define __kernel __attribute__((address_space(0))) 22 # define __user __attribute__((noderef, address_space(__user))) 23 # define __iomem __attribute__((noderef, address_space(__iomem))) 24 # define __percpu __attribute__((noderef, address_space(__percpu))) 25 # define __rcu __attribute__((noderef, address_space(__rcu))) 26 static inline void __chk_user_ptr(const volatile void __user *ptr) { } 27 static inline void __chk_io_ptr(const volatile void __iomem *ptr) { } 28 /* context/locking */ 29 # define __must_hold(x) __attribute__((context(x,1,1))) 30 # define __acquires(x) __attribute__((context(x,0,1))) 31 # define __cond_acquires(x) __attribute__((context(x,0,-1))) 32 # define __releases(x) __attribute__((context(x,1,0))) 33 # define __acquire(x) __context__(x,1) 34 # define __release(x) __context__(x,-1) 35 # define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0) 36 /* other */ 37 # define __force __attribute__((force)) 38 # define __nocast __attribute__((nocast)) 39 # define __safe __attribute__((safe)) 40 # define __private __attribute__((noderef)) 41 # define ACCESS_PRIVATE(p, member) (*((typeof((p)->member) __force *) &(p)->member)) 42 #else /* __CHECKER__ */ 43 /* address spaces */ 44 # define __kernel 45 # ifdef STRUCTLEAK_PLUGIN 46 # define __user __attribute__((user)) 47 # else 48 # define __user BTF_TYPE_TAG(user) 49 # endif 50 # define __iomem 51 # define __percpu BTF_TYPE_TAG(percpu) 52 # define __rcu BTF_TYPE_TAG(rcu) 53 54 # define __chk_user_ptr(x) (void)0 55 # define __chk_io_ptr(x) (void)0 56 /* context/locking */ 57 # define __must_hold(x) 58 # define __acquires(x) 59 # define __cond_acquires(x) 60 # define __releases(x) 61 # define __acquire(x) (void)0 62 # define __release(x) (void)0 63 # define __cond_lock(x,c) (c) 64 /* other */ 65 # define __force 66 # define __nocast 67 # define __safe 68 # define __private 69 # define ACCESS_PRIVATE(p, member) ((p)->member) 70 # define __builtin_warning(x, y...) (1) 71 #endif /* __CHECKER__ */ 72 73 /* Indirect macros required for expanded argument pasting, eg. __LINE__. */ 74 #define ___PASTE(a,b) a##b 75 #define __PASTE(a,b) ___PASTE(a,b) 76 77 #ifdef __KERNEL__ 78 79 /* Attributes */ 80 #include <linux/compiler_attributes.h> 81 82 #if CONFIG_FUNCTION_ALIGNMENT > 0 83 #define __function_aligned __aligned(CONFIG_FUNCTION_ALIGNMENT) 84 #else 85 #define __function_aligned 86 #endif 87 88 /* 89 * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-cold-function-attribute 90 * gcc: https://gcc.gnu.org/onlinedocs/gcc/Label-Attributes.html#index-cold-label-attribute 91 * 92 * When -falign-functions=N is in use, we must avoid the cold attribute as 93 * contemporary versions of GCC drop the alignment for cold functions. Worse, 94 * GCC can implicitly mark callees of cold functions as cold themselves, so 95 * it's not sufficient to add __function_aligned here as that will not ensure 96 * that callees are correctly aligned. 97 * 98 * See: 99 * 100 * https://lore.kernel.org/lkml/Y77%2FqVgvaJidFpYt@FVFF77S0Q05N 101 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88345#c9 102 */ 103 #if !defined(CONFIG_CC_IS_GCC) || (CONFIG_FUNCTION_ALIGNMENT == 0) 104 #define __cold __attribute__((__cold__)) 105 #else 106 #define __cold 107 #endif 108 109 /* Builtins */ 110 111 /* 112 * __has_builtin is supported on gcc >= 10, clang >= 3 and icc >= 21. 113 * In the meantime, to support gcc < 10, we implement __has_builtin 114 * by hand. 115 */ 116 #ifndef __has_builtin 117 #define __has_builtin(x) (0) 118 #endif 119 120 /* Compiler specific macros. */ 121 #ifdef __clang__ 122 #include <linux/compiler-clang.h> 123 #elif defined(__INTEL_COMPILER) 124 #include <linux/compiler-intel.h> 125 #elif defined(__GNUC__) 126 /* The above compilers also define __GNUC__, so order is important here. */ 127 #include <linux/compiler-gcc.h> 128 #else 129 #error "Unknown compiler" 130 #endif 131 132 /* 133 * Some architectures need to provide custom definitions of macros provided 134 * by linux/compiler-*.h, and can do so using asm/compiler.h. We include that 135 * conditionally rather than using an asm-generic wrapper in order to avoid 136 * build failures if any C compilation, which will include this file via an 137 * -include argument in c_flags, occurs prior to the asm-generic wrappers being 138 * generated. 139 */ 140 #ifdef CONFIG_HAVE_ARCH_COMPILER_H 141 #include <asm/compiler.h> 142 #endif 143 144 struct ftrace_branch_data { 145 const char *func; 146 const char *file; 147 unsigned line; 148 union { 149 struct { 150 unsigned long correct; 151 unsigned long incorrect; 152 }; 153 struct { 154 unsigned long miss; 155 unsigned long hit; 156 }; 157 unsigned long miss_hit[2]; 158 }; 159 }; 160 161 struct ftrace_likely_data { 162 struct ftrace_branch_data data; 163 unsigned long constant; 164 }; 165 166 #if defined(CC_USING_HOTPATCH) 167 #define notrace __attribute__((hotpatch(0, 0))) 168 #elif defined(CC_USING_PATCHABLE_FUNCTION_ENTRY) 169 #define notrace __attribute__((patchable_function_entry(0, 0))) 170 #else 171 #define notrace __attribute__((__no_instrument_function__)) 172 #endif 173 174 /* 175 * it doesn't make sense on ARM (currently the only user of __naked) 176 * to trace naked functions because then mcount is called without 177 * stack and frame pointer being set up and there is no chance to 178 * restore the lr register to the value before mcount was called. 179 */ 180 #define __naked __attribute__((__naked__)) notrace 181 182 /* 183 * Prefer gnu_inline, so that extern inline functions do not emit an 184 * externally visible function. This makes extern inline behave as per gnu89 185 * semantics rather than c99. This prevents multiple symbol definition errors 186 * of extern inline functions at link time. 187 * A lot of inline functions can cause havoc with function tracing. 188 */ 189 #define inline inline __gnu_inline __inline_maybe_unused notrace 190 191 /* 192 * gcc provides both __inline__ and __inline as alternate spellings of 193 * the inline keyword, though the latter is undocumented. New kernel 194 * code should only use the inline spelling, but some existing code 195 * uses __inline__. Since we #define inline above, to ensure 196 * __inline__ has the same semantics, we need this #define. 197 * 198 * However, the spelling __inline is strictly reserved for referring 199 * to the bare keyword. 200 */ 201 #define __inline__ inline 202 203 /* 204 * GCC does not warn about unused static inline functions for -Wunused-function. 205 * Suppress the warning in clang as well by using __maybe_unused, but enable it 206 * for W=1 build. This will allow clang to find unused functions. Remove the 207 * __inline_maybe_unused entirely after fixing most of -Wunused-function warnings. 208 */ 209 #ifdef KBUILD_EXTRA_WARN1 210 #define __inline_maybe_unused 211 #else 212 #define __inline_maybe_unused __maybe_unused 213 #endif 214 215 /* 216 * Rather then using noinline to prevent stack consumption, use 217 * noinline_for_stack instead. For documentation reasons. 218 */ 219 #define noinline_for_stack noinline 220 221 /* 222 * Sanitizer helper attributes: Because using __always_inline and 223 * __no_sanitize_* conflict, provide helper attributes that will either expand 224 * to __no_sanitize_* in compilation units where instrumentation is enabled 225 * (__SANITIZE_*__), or __always_inline in compilation units without 226 * instrumentation (__SANITIZE_*__ undefined). 227 */ 228 #ifdef __SANITIZE_ADDRESS__ 229 /* 230 * We can't declare function 'inline' because __no_sanitize_address conflicts 231 * with inlining. Attempt to inline it may cause a build failure. 232 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368 233 * '__maybe_unused' allows us to avoid defined-but-not-used warnings. 234 */ 235 # define __no_kasan_or_inline __no_sanitize_address notrace __maybe_unused 236 # define __no_sanitize_or_inline __no_kasan_or_inline 237 #else 238 # define __no_kasan_or_inline __always_inline 239 #endif 240 241 #ifdef __SANITIZE_THREAD__ 242 /* 243 * Clang still emits instrumentation for __tsan_func_{entry,exit}() and builtin 244 * atomics even with __no_sanitize_thread (to avoid false positives in userspace 245 * ThreadSanitizer). The kernel's requirements are stricter and we really do not 246 * want any instrumentation with __no_kcsan. 247 * 248 * Therefore we add __disable_sanitizer_instrumentation where available to 249 * disable all instrumentation. See Kconfig.kcsan where this is mandatory. 250 */ 251 # define __no_kcsan __no_sanitize_thread __disable_sanitizer_instrumentation 252 # define __no_sanitize_or_inline __no_kcsan notrace __maybe_unused 253 #else 254 # define __no_kcsan 255 #endif 256 257 #ifndef __no_sanitize_or_inline 258 #define __no_sanitize_or_inline __always_inline 259 #endif 260 261 /* Section for code which can't be instrumented at all */ 262 #define __noinstr_section(section) \ 263 noinline notrace __attribute((__section__(section))) \ 264 __no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage \ 265 __no_sanitize_memory 266 267 #define noinstr __noinstr_section(".noinstr.text") 268 269 /* 270 * The __cpuidle section is used twofold: 271 * 272 * 1) the original use -- identifying if a CPU is 'stuck' in idle state based 273 * on it's instruction pointer. See cpu_in_idle(). 274 * 275 * 2) supressing instrumentation around where cpuidle disables RCU; where the 276 * function isn't strictly required for #1, this is interchangeable with 277 * noinstr. 278 */ 279 #define __cpuidle __noinstr_section(".cpuidle.text") 280 281 #endif /* __KERNEL__ */ 282 283 #endif /* __ASSEMBLY__ */ 284 285 /* 286 * The below symbols may be defined for one or more, but not ALL, of the above 287 * compilers. We don't consider that to be an error, so set them to nothing. 288 * For example, some of them are for compiler specific plugins. 289 */ 290 #ifndef __latent_entropy 291 # define __latent_entropy 292 #endif 293 294 #if defined(RANDSTRUCT) && !defined(__CHECKER__) 295 # define __randomize_layout __designated_init __attribute__((randomize_layout)) 296 # define __no_randomize_layout __attribute__((no_randomize_layout)) 297 /* This anon struct can add padding, so only enable it under randstruct. */ 298 # define randomized_struct_fields_start struct { 299 # define randomized_struct_fields_end } __randomize_layout; 300 #else 301 # define __randomize_layout __designated_init 302 # define __no_randomize_layout 303 # define randomized_struct_fields_start 304 # define randomized_struct_fields_end 305 #endif 306 307 #ifndef __noscs 308 # define __noscs 309 #endif 310 311 #ifndef __nocfi 312 # define __nocfi 313 #endif 314 315 /* 316 * Any place that could be marked with the "alloc_size" attribute is also 317 * a place to be marked with the "malloc" attribute, except those that may 318 * be performing a _reallocation_, as that may alias the existing pointer. 319 * For these, use __realloc_size(). 320 */ 321 #ifdef __alloc_size__ 322 # define __alloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) __malloc 323 # define __realloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) 324 #else 325 # define __alloc_size(x, ...) __malloc 326 # define __realloc_size(x, ...) 327 #endif 328 329 #ifndef asm_volatile_goto 330 #define asm_volatile_goto(x...) asm goto(x) 331 #endif 332 333 #ifdef CONFIG_CC_HAS_ASM_INLINE 334 #define asm_inline asm __inline 335 #else 336 #define asm_inline asm 337 #endif 338 339 /* Are two types/vars the same type (ignoring qualifiers)? */ 340 #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) 341 342 /* 343 * __unqual_scalar_typeof(x) - Declare an unqualified scalar type, leaving 344 * non-scalar types unchanged. 345 */ 346 /* 347 * Prefer C11 _Generic for better compile-times and simpler code. Note: 'char' 348 * is not type-compatible with 'signed char', and we define a separate case. 349 */ 350 #define __scalar_type_to_expr_cases(type) \ 351 unsigned type: (unsigned type)0, \ 352 signed type: (signed type)0 353 354 #define __unqual_scalar_typeof(x) typeof( \ 355 _Generic((x), \ 356 char: (char)0, \ 357 __scalar_type_to_expr_cases(char), \ 358 __scalar_type_to_expr_cases(short), \ 359 __scalar_type_to_expr_cases(int), \ 360 __scalar_type_to_expr_cases(long), \ 361 __scalar_type_to_expr_cases(long long), \ 362 default: (x))) 363 364 /* Is this type a native word size -- useful for atomic operations */ 365 #define __native_word(t) \ 366 (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \ 367 sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) 368 369 #ifdef __OPTIMIZE__ 370 # define __compiletime_assert(condition, msg, prefix, suffix) \ 371 do { \ 372 /* \ 373 * __noreturn is needed to give the compiler enough \ 374 * information to avoid certain possibly-uninitialized \ 375 * warnings (regardless of the build failing). \ 376 */ \ 377 __noreturn extern void prefix ## suffix(void) \ 378 __compiletime_error(msg); \ 379 if (!(condition)) \ 380 prefix ## suffix(); \ 381 } while (0) 382 #else 383 # define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0) 384 #endif 385 386 #define _compiletime_assert(condition, msg, prefix, suffix) \ 387 __compiletime_assert(condition, msg, prefix, suffix) 388 389 /** 390 * compiletime_assert - break build and emit msg if condition is false 391 * @condition: a compile-time constant condition to check 392 * @msg: a message to emit if condition is false 393 * 394 * In tradition of POSIX assert, this macro will break the build if the 395 * supplied condition is *false*, emitting the supplied error message if the 396 * compiler has support to do so. 397 */ 398 #define compiletime_assert(condition, msg) \ 399 _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) 400 401 #define compiletime_assert_atomic_type(t) \ 402 compiletime_assert(__native_word(t), \ 403 "Need native word sized stores/loads for atomicity.") 404 405 /* Helpers for emitting diagnostics in pragmas. */ 406 #ifndef __diag 407 #define __diag(string) 408 #endif 409 410 #ifndef __diag_GCC 411 #define __diag_GCC(version, severity, string) 412 #endif 413 414 #define __diag_push() __diag(push) 415 #define __diag_pop() __diag(pop) 416 417 #define __diag_ignore(compiler, version, option, comment) \ 418 __diag_ ## compiler(version, ignore, option) 419 #define __diag_warn(compiler, version, option, comment) \ 420 __diag_ ## compiler(version, warn, option) 421 #define __diag_error(compiler, version, option, comment) \ 422 __diag_ ## compiler(version, error, option) 423 424 #ifndef __diag_ignore_all 425 #define __diag_ignore_all(option, comment) 426 #endif 427 428 #endif /* __LINUX_COMPILER_TYPES_H */ 429