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