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