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