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		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(__GNUC__)
124 /* The above compilers also define __GNUC__, so order is important here. */
125 #include <linux/compiler-gcc.h>
126 #else
127 #error "Unknown compiler"
128 #endif
129 
130 /*
131  * Some architectures need to provide custom definitions of macros provided
132  * by linux/compiler-*.h, and can do so using asm/compiler.h. We include that
133  * conditionally rather than using an asm-generic wrapper in order to avoid
134  * build failures if any C compilation, which will include this file via an
135  * -include argument in c_flags, occurs prior to the asm-generic wrappers being
136  * generated.
137  */
138 #ifdef CONFIG_HAVE_ARCH_COMPILER_H
139 #include <asm/compiler.h>
140 #endif
141 
142 struct ftrace_branch_data {
143 	const char *func;
144 	const char *file;
145 	unsigned line;
146 	union {
147 		struct {
148 			unsigned long correct;
149 			unsigned long incorrect;
150 		};
151 		struct {
152 			unsigned long miss;
153 			unsigned long hit;
154 		};
155 		unsigned long miss_hit[2];
156 	};
157 };
158 
159 struct ftrace_likely_data {
160 	struct ftrace_branch_data	data;
161 	unsigned long			constant;
162 };
163 
164 #if defined(CC_USING_HOTPATCH)
165 #define notrace			__attribute__((hotpatch(0, 0)))
166 #elif defined(CC_USING_PATCHABLE_FUNCTION_ENTRY)
167 #define notrace			__attribute__((patchable_function_entry(0, 0)))
168 #else
169 #define notrace			__attribute__((__no_instrument_function__))
170 #endif
171 
172 /*
173  * it doesn't make sense on ARM (currently the only user of __naked)
174  * to trace naked functions because then mcount is called without
175  * stack and frame pointer being set up and there is no chance to
176  * restore the lr register to the value before mcount was called.
177  */
178 #define __naked			__attribute__((__naked__)) notrace
179 
180 /*
181  * Prefer gnu_inline, so that extern inline functions do not emit an
182  * externally visible function. This makes extern inline behave as per gnu89
183  * semantics rather than c99. This prevents multiple symbol definition errors
184  * of extern inline functions at link time.
185  * A lot of inline functions can cause havoc with function tracing.
186  */
187 #define inline inline __gnu_inline __inline_maybe_unused notrace
188 
189 /*
190  * gcc provides both __inline__ and __inline as alternate spellings of
191  * the inline keyword, though the latter is undocumented. New kernel
192  * code should only use the inline spelling, but some existing code
193  * uses __inline__. Since we #define inline above, to ensure
194  * __inline__ has the same semantics, we need this #define.
195  *
196  * However, the spelling __inline is strictly reserved for referring
197  * to the bare keyword.
198  */
199 #define __inline__ inline
200 
201 /*
202  * GCC does not warn about unused static inline functions for -Wunused-function.
203  * Suppress the warning in clang as well by using __maybe_unused, but enable it
204  * for W=1 build. This will allow clang to find unused functions. Remove the
205  * __inline_maybe_unused entirely after fixing most of -Wunused-function warnings.
206  */
207 #ifdef KBUILD_EXTRA_WARN1
208 #define __inline_maybe_unused
209 #else
210 #define __inline_maybe_unused __maybe_unused
211 #endif
212 
213 /*
214  * Rather then using noinline to prevent stack consumption, use
215  * noinline_for_stack instead.  For documentation reasons.
216  */
217 #define noinline_for_stack noinline
218 
219 /*
220  * Sanitizer helper attributes: Because using __always_inline and
221  * __no_sanitize_* conflict, provide helper attributes that will either expand
222  * to __no_sanitize_* in compilation units where instrumentation is enabled
223  * (__SANITIZE_*__), or __always_inline in compilation units without
224  * instrumentation (__SANITIZE_*__ undefined).
225  */
226 #ifdef __SANITIZE_ADDRESS__
227 /*
228  * We can't declare function 'inline' because __no_sanitize_address conflicts
229  * with inlining. Attempt to inline it may cause a build failure.
230  *     https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
231  * '__maybe_unused' allows us to avoid defined-but-not-used warnings.
232  */
233 # define __no_kasan_or_inline __no_sanitize_address notrace __maybe_unused
234 # define __no_sanitize_or_inline __no_kasan_or_inline
235 #else
236 # define __no_kasan_or_inline __always_inline
237 #endif
238 
239 #ifdef __SANITIZE_THREAD__
240 /*
241  * Clang still emits instrumentation for __tsan_func_{entry,exit}() and builtin
242  * atomics even with __no_sanitize_thread (to avoid false positives in userspace
243  * ThreadSanitizer). The kernel's requirements are stricter and we really do not
244  * want any instrumentation with __no_kcsan.
245  *
246  * Therefore we add __disable_sanitizer_instrumentation where available to
247  * disable all instrumentation. See Kconfig.kcsan where this is mandatory.
248  */
249 # define __no_kcsan __no_sanitize_thread __disable_sanitizer_instrumentation
250 # define __no_sanitize_or_inline __no_kcsan notrace __maybe_unused
251 #else
252 # define __no_kcsan
253 #endif
254 
255 #ifndef __no_sanitize_or_inline
256 #define __no_sanitize_or_inline __always_inline
257 #endif
258 
259 /* Section for code which can't be instrumented at all */
260 #define __noinstr_section(section)					\
261 	noinline notrace __attribute((__section__(section)))		\
262 	__no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage \
263 	__no_sanitize_memory
264 
265 #define noinstr __noinstr_section(".noinstr.text")
266 
267 /*
268  * The __cpuidle section is used twofold:
269  *
270  *  1) the original use -- identifying if a CPU is 'stuck' in idle state based
271  *     on it's instruction pointer. See cpu_in_idle().
272  *
273  *  2) supressing instrumentation around where cpuidle disables RCU; where the
274  *     function isn't strictly required for #1, this is interchangeable with
275  *     noinstr.
276  */
277 #define __cpuidle __noinstr_section(".cpuidle.text")
278 
279 #endif /* __KERNEL__ */
280 
281 #endif /* __ASSEMBLY__ */
282 
283 /*
284  * The below symbols may be defined for one or more, but not ALL, of the above
285  * compilers. We don't consider that to be an error, so set them to nothing.
286  * For example, some of them are for compiler specific plugins.
287  */
288 #ifndef __latent_entropy
289 # define __latent_entropy
290 #endif
291 
292 #if defined(RANDSTRUCT) && !defined(__CHECKER__)
293 # define __randomize_layout __designated_init __attribute__((randomize_layout))
294 # define __no_randomize_layout __attribute__((no_randomize_layout))
295 /* This anon struct can add padding, so only enable it under randstruct. */
296 # define randomized_struct_fields_start	struct {
297 # define randomized_struct_fields_end	} __randomize_layout;
298 #else
299 # define __randomize_layout __designated_init
300 # define __no_randomize_layout
301 # define randomized_struct_fields_start
302 # define randomized_struct_fields_end
303 #endif
304 
305 #ifndef __noscs
306 # define __noscs
307 #endif
308 
309 #ifndef __nocfi
310 # define __nocfi
311 #endif
312 
313 /*
314  * Any place that could be marked with the "alloc_size" attribute is also
315  * a place to be marked with the "malloc" attribute, except those that may
316  * be performing a _reallocation_, as that may alias the existing pointer.
317  * For these, use __realloc_size().
318  */
319 #ifdef __alloc_size__
320 # define __alloc_size(x, ...)	__alloc_size__(x, ## __VA_ARGS__) __malloc
321 # define __realloc_size(x, ...)	__alloc_size__(x, ## __VA_ARGS__)
322 #else
323 # define __alloc_size(x, ...)	__malloc
324 # define __realloc_size(x, ...)
325 #endif
326 
327 #ifndef asm_volatile_goto
328 #define asm_volatile_goto(x...) asm goto(x)
329 #endif
330 
331 #ifdef CONFIG_CC_HAS_ASM_INLINE
332 #define asm_inline asm __inline
333 #else
334 #define asm_inline asm
335 #endif
336 
337 /* Are two types/vars the same type (ignoring qualifiers)? */
338 #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
339 
340 /*
341  * __unqual_scalar_typeof(x) - Declare an unqualified scalar type, leaving
342  *			       non-scalar types unchanged.
343  */
344 /*
345  * Prefer C11 _Generic for better compile-times and simpler code. Note: 'char'
346  * is not type-compatible with 'signed char', and we define a separate case.
347  */
348 #define __scalar_type_to_expr_cases(type)				\
349 		unsigned type:	(unsigned type)0,			\
350 		signed type:	(signed type)0
351 
352 #define __unqual_scalar_typeof(x) typeof(				\
353 		_Generic((x),						\
354 			 char:	(char)0,				\
355 			 __scalar_type_to_expr_cases(char),		\
356 			 __scalar_type_to_expr_cases(short),		\
357 			 __scalar_type_to_expr_cases(int),		\
358 			 __scalar_type_to_expr_cases(long),		\
359 			 __scalar_type_to_expr_cases(long long),	\
360 			 default: (x)))
361 
362 /* Is this type a native word size -- useful for atomic operations */
363 #define __native_word(t) \
364 	(sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \
365 	 sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long))
366 
367 #ifdef __OPTIMIZE__
368 # define __compiletime_assert(condition, msg, prefix, suffix)		\
369 	do {								\
370 		/*							\
371 		 * __noreturn is needed to give the compiler enough	\
372 		 * information to avoid certain possibly-uninitialized	\
373 		 * warnings (regardless of the build failing).		\
374 		 */							\
375 		__noreturn extern void prefix ## suffix(void)		\
376 			__compiletime_error(msg);			\
377 		if (!(condition))					\
378 			prefix ## suffix();				\
379 	} while (0)
380 #else
381 # define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0)
382 #endif
383 
384 #define _compiletime_assert(condition, msg, prefix, suffix) \
385 	__compiletime_assert(condition, msg, prefix, suffix)
386 
387 /**
388  * compiletime_assert - break build and emit msg if condition is false
389  * @condition: a compile-time constant condition to check
390  * @msg:       a message to emit if condition is false
391  *
392  * In tradition of POSIX assert, this macro will break the build if the
393  * supplied condition is *false*, emitting the supplied error message if the
394  * compiler has support to do so.
395  */
396 #define compiletime_assert(condition, msg) \
397 	_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
398 
399 #define compiletime_assert_atomic_type(t)				\
400 	compiletime_assert(__native_word(t),				\
401 		"Need native word sized stores/loads for atomicity.")
402 
403 /* Helpers for emitting diagnostics in pragmas. */
404 #ifndef __diag
405 #define __diag(string)
406 #endif
407 
408 #ifndef __diag_GCC
409 #define __diag_GCC(version, severity, string)
410 #endif
411 
412 #define __diag_push()	__diag(push)
413 #define __diag_pop()	__diag(pop)
414 
415 #define __diag_ignore(compiler, version, option, comment) \
416 	__diag_ ## compiler(version, ignore, option)
417 #define __diag_warn(compiler, version, option, comment) \
418 	__diag_ ## compiler(version, warn, option)
419 #define __diag_error(compiler, version, option, comment) \
420 	__diag_ ## compiler(version, error, option)
421 
422 #ifndef __diag_ignore_all
423 #define __diag_ignore_all(option, comment)
424 #endif
425 
426 #endif /* __LINUX_COMPILER_TYPES_H */
427