1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _LINUX_LINKAGE_H |
3 | #define _LINUX_LINKAGE_H |
4 | |
5 | #include <linux/compiler_types.h> |
6 | #include <linux/stringify.h> |
7 | #include <linux/export.h> |
8 | #include <asm/linkage.h> |
9 | |
10 | /* Some toolchains use other characters (e.g. '`') to mark new line in macro */ |
11 | #ifndef ASM_NL |
12 | #define ASM_NL ; |
13 | #endif |
14 | |
15 | #ifdef __cplusplus |
16 | #define CPP_ASMLINKAGE extern "C" |
17 | #else |
18 | #define CPP_ASMLINKAGE |
19 | #endif |
20 | |
21 | #ifndef asmlinkage |
22 | #define asmlinkage CPP_ASMLINKAGE |
23 | #endif |
24 | |
25 | #ifndef cond_syscall |
26 | #define cond_syscall(x) asm( \ |
27 | ".weak " __stringify(x) "\n\t" \ |
28 | ".set " __stringify(x) "," \ |
29 | __stringify(sys_ni_syscall)) |
30 | #endif |
31 | |
32 | #ifndef SYSCALL_ALIAS |
33 | #define SYSCALL_ALIAS(alias, name) asm( \ |
34 | ".globl " __stringify(alias) "\n\t" \ |
35 | ".set " __stringify(alias) "," \ |
36 | __stringify(name)) |
37 | #endif |
38 | |
39 | #define __page_aligned_data __section(".data..page_aligned") __aligned(PAGE_SIZE) |
40 | #define __page_aligned_bss __section(".bss..page_aligned") __aligned(PAGE_SIZE) |
41 | |
42 | /* |
43 | * For assembly routines. |
44 | * |
45 | * Note when using these that you must specify the appropriate |
46 | * alignment directives yourself |
47 | */ |
48 | #define __PAGE_ALIGNED_DATA .section ".data..page_aligned", "aw" |
49 | #define __PAGE_ALIGNED_BSS .section ".bss..page_aligned", "aw" |
50 | |
51 | /* |
52 | * This is used by architectures to keep arguments on the stack |
53 | * untouched by the compiler by keeping them live until the end. |
54 | * The argument stack may be owned by the assembly-language |
55 | * caller, not the callee, and gcc doesn't always understand |
56 | * that. |
57 | * |
58 | * We have the return value, and a maximum of six arguments. |
59 | * |
60 | * This should always be followed by a "return ret" for the |
61 | * protection to work (ie no more work that the compiler might |
62 | * end up needing stack temporaries for). |
63 | */ |
64 | /* Assembly files may be compiled with -traditional .. */ |
65 | #ifndef __ASSEMBLY__ |
66 | #ifndef asmlinkage_protect |
67 | # define asmlinkage_protect(n, ret, args...) do { } while (0) |
68 | #endif |
69 | #endif |
70 | |
71 | #ifndef __ALIGN |
72 | #define __ALIGN .align 4,0x90 |
73 | #define __ALIGN_STR ".align 4,0x90" |
74 | #endif |
75 | |
76 | #ifdef __ASSEMBLY__ |
77 | |
78 | /* SYM_T_FUNC -- type used by assembler to mark functions */ |
79 | #ifndef SYM_T_FUNC |
80 | #define SYM_T_FUNC STT_FUNC |
81 | #endif |
82 | |
83 | /* SYM_T_OBJECT -- type used by assembler to mark data */ |
84 | #ifndef SYM_T_OBJECT |
85 | #define SYM_T_OBJECT STT_OBJECT |
86 | #endif |
87 | |
88 | /* SYM_T_NONE -- type used by assembler to mark entries of unknown type */ |
89 | #ifndef SYM_T_NONE |
90 | #define SYM_T_NONE STT_NOTYPE |
91 | #endif |
92 | |
93 | /* SYM_A_* -- align the symbol? */ |
94 | #define SYM_A_ALIGN ALIGN |
95 | #define SYM_A_NONE /* nothing */ |
96 | |
97 | /* SYM_L_* -- linkage of symbols */ |
98 | #define SYM_L_GLOBAL(name) .globl name |
99 | #define SYM_L_WEAK(name) .weak name |
100 | #define SYM_L_LOCAL(name) /* nothing */ |
101 | |
102 | #ifndef LINKER_SCRIPT |
103 | #define ALIGN __ALIGN |
104 | #define ALIGN_STR __ALIGN_STR |
105 | |
106 | /* === DEPRECATED annotations === */ |
107 | |
108 | #ifndef CONFIG_ARCH_USE_SYM_ANNOTATIONS |
109 | #ifndef GLOBAL |
110 | /* deprecated, use SYM_DATA*, SYM_ENTRY, or similar */ |
111 | #define GLOBAL(name) \ |
112 | .globl name ASM_NL \ |
113 | name: |
114 | #endif |
115 | |
116 | #ifndef ENTRY |
117 | /* deprecated, use SYM_FUNC_START */ |
118 | #define ENTRY(name) \ |
119 | SYM_FUNC_START(name) |
120 | #endif |
121 | #endif /* CONFIG_ARCH_USE_SYM_ANNOTATIONS */ |
122 | #endif /* LINKER_SCRIPT */ |
123 | |
124 | #ifndef CONFIG_ARCH_USE_SYM_ANNOTATIONS |
125 | #ifndef WEAK |
126 | /* deprecated, use SYM_FUNC_START_WEAK* */ |
127 | #define WEAK(name) \ |
128 | SYM_FUNC_START_WEAK(name) |
129 | #endif |
130 | |
131 | #ifndef END |
132 | /* deprecated, use SYM_FUNC_END, SYM_DATA_END, or SYM_END */ |
133 | #define END(name) \ |
134 | .size name, .-name |
135 | #endif |
136 | |
137 | /* If symbol 'name' is treated as a subroutine (gets called, and returns) |
138 | * then please use ENDPROC to mark 'name' as STT_FUNC for the benefit of |
139 | * static analysis tools such as stack depth analyzer. |
140 | */ |
141 | #ifndef ENDPROC |
142 | /* deprecated, use SYM_FUNC_END */ |
143 | #define ENDPROC(name) \ |
144 | SYM_FUNC_END(name) |
145 | #endif |
146 | #endif /* CONFIG_ARCH_USE_SYM_ANNOTATIONS */ |
147 | |
148 | /* === generic annotations === */ |
149 | |
150 | /* SYM_ENTRY -- use only if you have to for non-paired symbols */ |
151 | #ifndef SYM_ENTRY |
152 | #define SYM_ENTRY(name, linkage, align...) \ |
153 | linkage(name) ASM_NL \ |
154 | align ASM_NL \ |
155 | name: |
156 | #endif |
157 | |
158 | /* SYM_START -- use only if you have to */ |
159 | #ifndef SYM_START |
160 | #define SYM_START(name, linkage, align...) \ |
161 | SYM_ENTRY(name, linkage, align) |
162 | #endif |
163 | |
164 | /* SYM_END -- use only if you have to */ |
165 | #ifndef SYM_END |
166 | #define SYM_END(name, sym_type) \ |
167 | .type name sym_type ASM_NL \ |
168 | .set .L__sym_size_##name, .-name ASM_NL \ |
169 | .size name, .L__sym_size_##name |
170 | #endif |
171 | |
172 | /* SYM_ALIAS -- use only if you have to */ |
173 | #ifndef SYM_ALIAS |
174 | #define SYM_ALIAS(alias, name, linkage) \ |
175 | linkage(alias) ASM_NL \ |
176 | .set alias, name ASM_NL |
177 | #endif |
178 | |
179 | /* === code annotations === */ |
180 | |
181 | /* |
182 | * FUNC -- C-like functions (proper stack frame etc.) |
183 | * CODE -- non-C code (e.g. irq handlers with different, special stack etc.) |
184 | * |
185 | * Objtool validates stack for FUNC, but not for CODE. |
186 | * Objtool generates debug info for both FUNC & CODE, but needs special |
187 | * annotations for each CODE's start (to describe the actual stack frame). |
188 | * |
189 | * Objtool requires that all code must be contained in an ELF symbol. Symbol |
190 | * names that have a .L prefix do not emit symbol table entries. .L |
191 | * prefixed symbols can be used within a code region, but should be avoided for |
192 | * denoting a range of code via ``SYM_*_START/END`` annotations. |
193 | * |
194 | * ALIAS -- does not generate debug info -- the aliased function will |
195 | */ |
196 | |
197 | /* SYM_INNER_LABEL_ALIGN -- only for labels in the middle of code */ |
198 | #ifndef SYM_INNER_LABEL_ALIGN |
199 | #define SYM_INNER_LABEL_ALIGN(name, linkage) \ |
200 | .type name SYM_T_NONE ASM_NL \ |
201 | SYM_ENTRY(name, linkage, SYM_A_ALIGN) |
202 | #endif |
203 | |
204 | /* SYM_INNER_LABEL -- only for labels in the middle of code */ |
205 | #ifndef SYM_INNER_LABEL |
206 | #define SYM_INNER_LABEL(name, linkage) \ |
207 | .type name SYM_T_NONE ASM_NL \ |
208 | SYM_ENTRY(name, linkage, SYM_A_NONE) |
209 | #endif |
210 | |
211 | /* SYM_FUNC_START -- use for global functions */ |
212 | #ifndef SYM_FUNC_START |
213 | #define SYM_FUNC_START(name) \ |
214 | SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) |
215 | #endif |
216 | |
217 | /* SYM_FUNC_START_NOALIGN -- use for global functions, w/o alignment */ |
218 | #ifndef SYM_FUNC_START_NOALIGN |
219 | #define SYM_FUNC_START_NOALIGN(name) \ |
220 | SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE) |
221 | #endif |
222 | |
223 | /* SYM_FUNC_START_LOCAL -- use for local functions */ |
224 | #ifndef SYM_FUNC_START_LOCAL |
225 | #define SYM_FUNC_START_LOCAL(name) \ |
226 | SYM_START(name, SYM_L_LOCAL, SYM_A_ALIGN) |
227 | #endif |
228 | |
229 | /* SYM_FUNC_START_LOCAL_NOALIGN -- use for local functions, w/o alignment */ |
230 | #ifndef SYM_FUNC_START_LOCAL_NOALIGN |
231 | #define SYM_FUNC_START_LOCAL_NOALIGN(name) \ |
232 | SYM_START(name, SYM_L_LOCAL, SYM_A_NONE) |
233 | #endif |
234 | |
235 | /* SYM_FUNC_START_WEAK -- use for weak functions */ |
236 | #ifndef SYM_FUNC_START_WEAK |
237 | #define SYM_FUNC_START_WEAK(name) \ |
238 | SYM_START(name, SYM_L_WEAK, SYM_A_ALIGN) |
239 | #endif |
240 | |
241 | /* SYM_FUNC_START_WEAK_NOALIGN -- use for weak functions, w/o alignment */ |
242 | #ifndef SYM_FUNC_START_WEAK_NOALIGN |
243 | #define SYM_FUNC_START_WEAK_NOALIGN(name) \ |
244 | SYM_START(name, SYM_L_WEAK, SYM_A_NONE) |
245 | #endif |
246 | |
247 | /* |
248 | * SYM_FUNC_END -- the end of SYM_FUNC_START_LOCAL, SYM_FUNC_START, |
249 | * SYM_FUNC_START_WEAK, ... |
250 | */ |
251 | #ifndef SYM_FUNC_END |
252 | #define SYM_FUNC_END(name) \ |
253 | SYM_END(name, SYM_T_FUNC) |
254 | #endif |
255 | |
256 | /* |
257 | * SYM_FUNC_ALIAS -- define a global alias for an existing function |
258 | */ |
259 | #ifndef SYM_FUNC_ALIAS |
260 | #define SYM_FUNC_ALIAS(alias, name) \ |
261 | SYM_ALIAS(alias, name, SYM_L_GLOBAL) |
262 | #endif |
263 | |
264 | /* |
265 | * SYM_FUNC_ALIAS_LOCAL -- define a local alias for an existing function |
266 | */ |
267 | #ifndef SYM_FUNC_ALIAS_LOCAL |
268 | #define SYM_FUNC_ALIAS_LOCAL(alias, name) \ |
269 | SYM_ALIAS(alias, name, SYM_L_LOCAL) |
270 | #endif |
271 | |
272 | /* |
273 | * SYM_FUNC_ALIAS_WEAK -- define a weak global alias for an existing function |
274 | */ |
275 | #ifndef SYM_FUNC_ALIAS_WEAK |
276 | #define SYM_FUNC_ALIAS_WEAK(alias, name) \ |
277 | SYM_ALIAS(alias, name, SYM_L_WEAK) |
278 | #endif |
279 | |
280 | /* SYM_CODE_START -- use for non-C (special) functions */ |
281 | #ifndef SYM_CODE_START |
282 | #define SYM_CODE_START(name) \ |
283 | SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) |
284 | #endif |
285 | |
286 | /* SYM_CODE_START_NOALIGN -- use for non-C (special) functions, w/o alignment */ |
287 | #ifndef SYM_CODE_START_NOALIGN |
288 | #define SYM_CODE_START_NOALIGN(name) \ |
289 | SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE) |
290 | #endif |
291 | |
292 | /* SYM_CODE_START_LOCAL -- use for local non-C (special) functions */ |
293 | #ifndef SYM_CODE_START_LOCAL |
294 | #define SYM_CODE_START_LOCAL(name) \ |
295 | SYM_START(name, SYM_L_LOCAL, SYM_A_ALIGN) |
296 | #endif |
297 | |
298 | /* |
299 | * SYM_CODE_START_LOCAL_NOALIGN -- use for local non-C (special) functions, |
300 | * w/o alignment |
301 | */ |
302 | #ifndef SYM_CODE_START_LOCAL_NOALIGN |
303 | #define SYM_CODE_START_LOCAL_NOALIGN(name) \ |
304 | SYM_START(name, SYM_L_LOCAL, SYM_A_NONE) |
305 | #endif |
306 | |
307 | /* SYM_CODE_END -- the end of SYM_CODE_START_LOCAL, SYM_CODE_START, ... */ |
308 | #ifndef SYM_CODE_END |
309 | #define SYM_CODE_END(name) \ |
310 | SYM_END(name, SYM_T_NONE) |
311 | #endif |
312 | |
313 | /* === data annotations === */ |
314 | |
315 | /* SYM_DATA_START -- global data symbol */ |
316 | #ifndef SYM_DATA_START |
317 | #define SYM_DATA_START(name) \ |
318 | SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE) |
319 | #endif |
320 | |
321 | /* SYM_DATA_START -- local data symbol */ |
322 | #ifndef SYM_DATA_START_LOCAL |
323 | #define SYM_DATA_START_LOCAL(name) \ |
324 | SYM_START(name, SYM_L_LOCAL, SYM_A_NONE) |
325 | #endif |
326 | |
327 | /* SYM_DATA_END -- the end of SYM_DATA_START symbol */ |
328 | #ifndef SYM_DATA_END |
329 | #define SYM_DATA_END(name) \ |
330 | SYM_END(name, SYM_T_OBJECT) |
331 | #endif |
332 | |
333 | /* SYM_DATA_END_LABEL -- the labeled end of SYM_DATA_START symbol */ |
334 | #ifndef SYM_DATA_END_LABEL |
335 | #define SYM_DATA_END_LABEL(name, linkage, label) \ |
336 | linkage(label) ASM_NL \ |
337 | .type label SYM_T_OBJECT ASM_NL \ |
338 | label: \ |
339 | SYM_END(name, SYM_T_OBJECT) |
340 | #endif |
341 | |
342 | /* SYM_DATA -- start+end wrapper around simple global data */ |
343 | #ifndef SYM_DATA |
344 | #define SYM_DATA(name, data...) \ |
345 | SYM_DATA_START(name) ASM_NL \ |
346 | data ASM_NL \ |
347 | SYM_DATA_END(name) |
348 | #endif |
349 | |
350 | /* SYM_DATA_LOCAL -- start+end wrapper around simple local data */ |
351 | #ifndef SYM_DATA_LOCAL |
352 | #define SYM_DATA_LOCAL(name, data...) \ |
353 | SYM_DATA_START_LOCAL(name) ASM_NL \ |
354 | data ASM_NL \ |
355 | SYM_DATA_END(name) |
356 | #endif |
357 | |
358 | #endif /* __ASSEMBLY__ */ |
359 | |
360 | #endif /* _LINUX_LINKAGE_H */ |
361 | |