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1da177e4 LT |
1 | #ifndef _LINUX_INIT_H |
2 | #define _LINUX_INIT_H | |
3 | ||
1da177e4 LT |
4 | #include <linux/compiler.h> |
5 | ||
6 | /* These macros are used to mark some functions or | |
7 | * initialized data (doesn't apply to uninitialized data) | |
8 | * as `initialization' functions. The kernel can take this | |
9 | * as hint that the function is used only during the initialization | |
10 | * phase and free up used memory resources after | |
11 | * | |
12 | * Usage: | |
13 | * For functions: | |
14 | * | |
15 | * You should add __init immediately before the function name, like: | |
16 | * | |
17 | * static void __init initme(int x, int y) | |
18 | * { | |
19 | * extern int z; z = x * y; | |
20 | * } | |
21 | * | |
22 | * If the function has a prototype somewhere, you can also add | |
23 | * __init between closing brace of the prototype and semicolon: | |
24 | * | |
25 | * extern int initialize_foobar_device(int, int, int) __init; | |
26 | * | |
27 | * For initialized data: | |
28 | * You should insert __initdata between the variable name and equal | |
29 | * sign followed by value, e.g.: | |
30 | * | |
31 | * static int init_variable __initdata = 0; | |
ae52bb23 | 32 | * static const char linux_logo[] __initconst = { 0x32, 0x36, ... }; |
1da177e4 LT |
33 | * |
34 | * Don't forget to initialize data not at file scope, i.e. within a function, | |
35 | * as gcc otherwise puts the data into the bss section and not into the init | |
36 | * section. | |
37 | * | |
38 | * Also note, that this data cannot be "const". | |
39 | */ | |
40 | ||
41 | /* These are for everybody (although not all archs will actually | |
42 | discard it in modules) */ | |
fed1939c | 43 | #define __init __section(.init.text) __cold notrace |
f3fe866d | 44 | #define __initdata __section(.init.data) |
37c514e3 | 45 | #define __initconst __section(.init.rodata) |
f3fe866d | 46 | #define __exitdata __section(.exit.data) |
3ff6eecc | 47 | #define __exit_call __used __section(.exitcall.exit) |
1da177e4 | 48 | |
0e0d314e SR |
49 | /* modpost check for section mismatches during the kernel build. |
50 | * A section mismatch happens when there are references from a | |
51 | * code or data section to an init section (both code or data). | |
52 | * The init sections are (for most archs) discarded by the kernel | |
53 | * when early init has completed so all such references are potential bugs. | |
54 | * For exit sections the same issue exists. | |
55 | * The following markers are used for the cases where the reference to | |
312b1485 SR |
56 | * the *init / *exit section (code or data) is valid and will teach |
57 | * modpost not to issue a warning. | |
0e0d314e | 58 | * The markers follow same syntax rules as __init / __initdata. */ |
312b1485 SR |
59 | #define __ref __section(.ref.text) noinline |
60 | #define __refdata __section(.ref.data) | |
61 | #define __refconst __section(.ref.rodata) | |
62 | ||
312b1485 SR |
63 | /* compatibility defines */ |
64 | #define __init_refok __ref | |
65 | #define __initdata_refok __refdata | |
66 | #define __exit_refok __ref | |
67 | ||
0e0d314e | 68 | |
1da177e4 | 69 | #ifdef MODULE |
eb8f6890 | 70 | #define __exitused |
1da177e4 | 71 | #else |
eb8f6890 | 72 | #define __exitused __used |
1da177e4 LT |
73 | #endif |
74 | ||
eb8f6890 SR |
75 | #define __exit __section(.exit.text) __exitused __cold |
76 | ||
77 | /* Used for HOTPLUG */ | |
78 | #define __devinit __section(.devinit.text) __cold | |
79 | #define __devinitdata __section(.devinit.data) | |
80 | #define __devinitconst __section(.devinit.rodata) | |
81 | #define __devexit __section(.devexit.text) __exitused __cold | |
82 | #define __devexitdata __section(.devexit.data) | |
83 | #define __devexitconst __section(.devexit.rodata) | |
84 | ||
85 | /* Used for HOTPLUG_CPU */ | |
86 | #define __cpuinit __section(.cpuinit.text) __cold | |
87 | #define __cpuinitdata __section(.cpuinit.data) | |
88 | #define __cpuinitconst __section(.cpuinit.rodata) | |
89 | #define __cpuexit __section(.cpuexit.text) __exitused __cold | |
90 | #define __cpuexitdata __section(.cpuexit.data) | |
91 | #define __cpuexitconst __section(.cpuexit.rodata) | |
92 | ||
93 | /* Used for MEMORY_HOTPLUG */ | |
94 | #define __meminit __section(.meminit.text) __cold | |
95 | #define __meminitdata __section(.meminit.data) | |
96 | #define __meminitconst __section(.meminit.rodata) | |
97 | #define __memexit __section(.memexit.text) __exitused __cold | |
98 | #define __memexitdata __section(.memexit.data) | |
99 | #define __memexitconst __section(.memexit.rodata) | |
100 | ||
1da177e4 | 101 | /* For assembly routines */ |
7923f90f | 102 | #define __HEAD .section ".head.text","ax" |
1da177e4 | 103 | #define __INIT .section ".init.text","ax" |
86c0baf1 | 104 | #define __FINIT .previous |
eb8f6890 | 105 | |
838c4118 | 106 | #define __INITDATA .section ".init.data","aw" |
3f5e26ce | 107 | #define __INITRODATA .section ".init.rodata","a" |
9f9975a5 | 108 | #define __FINITDATA .previous |
1da177e4 | 109 | |
eb8f6890 SR |
110 | #define __DEVINIT .section ".devinit.text", "ax" |
111 | #define __DEVINITDATA .section ".devinit.data", "aw" | |
3f5e26ce | 112 | #define __DEVINITRODATA .section ".devinit.rodata", "a" |
eb8f6890 SR |
113 | |
114 | #define __CPUINIT .section ".cpuinit.text", "ax" | |
115 | #define __CPUINITDATA .section ".cpuinit.data", "aw" | |
3f5e26ce | 116 | #define __CPUINITRODATA .section ".cpuinit.rodata", "a" |
eb8f6890 SR |
117 | |
118 | #define __MEMINIT .section ".meminit.text", "ax" | |
119 | #define __MEMINITDATA .section ".meminit.data", "aw" | |
3f5e26ce | 120 | #define __MEMINITRODATA .section ".meminit.rodata", "a" |
eb8f6890 | 121 | |
312b1485 SR |
122 | /* silence warnings when references are OK */ |
123 | #define __REF .section ".ref.text", "ax" | |
124 | #define __REFDATA .section ".ref.data", "aw" | |
3f5e26ce | 125 | #define __REFCONST .section ".ref.rodata", "a" |
312b1485 | 126 | |
1da177e4 LT |
127 | #ifndef __ASSEMBLY__ |
128 | /* | |
129 | * Used for initialization calls.. | |
130 | */ | |
131 | typedef int (*initcall_t)(void); | |
132 | typedef void (*exitcall_t)(void); | |
133 | ||
134 | extern initcall_t __con_initcall_start[], __con_initcall_end[]; | |
135 | extern initcall_t __security_initcall_start[], __security_initcall_end[]; | |
136 | ||
137 | /* Defined in init/main.c */ | |
59f9415f | 138 | extern int do_one_initcall(initcall_t fn); |
30d7e0d4 ABL |
139 | extern char __initdata boot_command_line[]; |
140 | extern char *saved_command_line; | |
7e96287d | 141 | extern unsigned int reset_devices; |
77d47582 AB |
142 | |
143 | /* used by init/main.c */ | |
46595390 AB |
144 | void setup_arch(char **); |
145 | void prepare_namespace(void); | |
77d47582 | 146 | |
7d195a54 AB |
147 | extern void (*late_time_init)(void); |
148 | ||
1da177e4 LT |
149 | #endif |
150 | ||
151 | #ifndef MODULE | |
152 | ||
153 | #ifndef __ASSEMBLY__ | |
154 | ||
155 | /* initcalls are now grouped by functionality into separate | |
156 | * subsections. Ordering inside the subsections is determined | |
157 | * by link order. | |
158 | * For backwards compatibility, initcall() puts the call in | |
159 | * the device init subsection. | |
735a7ffb AM |
160 | * |
161 | * The `id' arg to __define_initcall() is needed so that multiple initcalls | |
162 | * can point at the same handler without causing duplicate-symbol build errors. | |
1da177e4 LT |
163 | */ |
164 | ||
735a7ffb | 165 | #define __define_initcall(level,fn,id) \ |
3ff6eecc | 166 | static initcall_t __initcall_##fn##id __used \ |
1da177e4 LT |
167 | __attribute__((__section__(".initcall" level ".init"))) = fn |
168 | ||
c2147a50 EGM |
169 | /* |
170 | * Early initcalls run before initializing SMP. | |
171 | * | |
172 | * Only for built-in code, not modules. | |
173 | */ | |
174 | #define early_initcall(fn) __define_initcall("early",fn,early) | |
175 | ||
b3438f82 LT |
176 | /* |
177 | * A "pure" initcall has no dependencies on anything else, and purely | |
178 | * initializes variables that couldn't be statically initialized. | |
179 | * | |
180 | * This only exists for built-in code, not for modules. | |
181 | */ | |
73dd1166 | 182 | #define pure_initcall(fn) __define_initcall("0",fn,0) |
b3438f82 | 183 | |
735a7ffb AM |
184 | #define core_initcall(fn) __define_initcall("1",fn,1) |
185 | #define core_initcall_sync(fn) __define_initcall("1s",fn,1s) | |
186 | #define postcore_initcall(fn) __define_initcall("2",fn,2) | |
187 | #define postcore_initcall_sync(fn) __define_initcall("2s",fn,2s) | |
188 | #define arch_initcall(fn) __define_initcall("3",fn,3) | |
189 | #define arch_initcall_sync(fn) __define_initcall("3s",fn,3s) | |
190 | #define subsys_initcall(fn) __define_initcall("4",fn,4) | |
191 | #define subsys_initcall_sync(fn) __define_initcall("4s",fn,4s) | |
192 | #define fs_initcall(fn) __define_initcall("5",fn,5) | |
193 | #define fs_initcall_sync(fn) __define_initcall("5s",fn,5s) | |
8d610dd5 | 194 | #define rootfs_initcall(fn) __define_initcall("rootfs",fn,rootfs) |
735a7ffb AM |
195 | #define device_initcall(fn) __define_initcall("6",fn,6) |
196 | #define device_initcall_sync(fn) __define_initcall("6s",fn,6s) | |
197 | #define late_initcall(fn) __define_initcall("7",fn,7) | |
198 | #define late_initcall_sync(fn) __define_initcall("7s",fn,7s) | |
1da177e4 LT |
199 | |
200 | #define __initcall(fn) device_initcall(fn) | |
201 | ||
202 | #define __exitcall(fn) \ | |
203 | static exitcall_t __exitcall_##fn __exit_call = fn | |
204 | ||
205 | #define console_initcall(fn) \ | |
206 | static initcall_t __initcall_##fn \ | |
3ff6eecc | 207 | __used __section(.con_initcall.init) = fn |
1da177e4 LT |
208 | |
209 | #define security_initcall(fn) \ | |
210 | static initcall_t __initcall_##fn \ | |
3ff6eecc | 211 | __used __section(.security_initcall.init) = fn |
1da177e4 LT |
212 | |
213 | struct obs_kernel_param { | |
214 | const char *str; | |
215 | int (*setup_func)(char *); | |
216 | int early; | |
217 | }; | |
218 | ||
219 | /* | |
220 | * Only for really core code. See moduleparam.h for the normal way. | |
221 | * | |
222 | * Force the alignment so the compiler doesn't space elements of the | |
223 | * obs_kernel_param "array" too far apart in .init.setup. | |
224 | */ | |
225 | #define __setup_param(str, unique_id, fn, early) \ | |
fd6c3a8d JB |
226 | static const char __setup_str_##unique_id[] __initconst \ |
227 | __aligned(1) = str; \ | |
1da177e4 | 228 | static struct obs_kernel_param __setup_##unique_id \ |
3ff6eecc | 229 | __used __section(.init.setup) \ |
1da177e4 LT |
230 | __attribute__((aligned((sizeof(long))))) \ |
231 | = { __setup_str_##unique_id, fn, early } | |
232 | ||
1da177e4 LT |
233 | #define __setup(str, fn) \ |
234 | __setup_param(str, fn, fn, 0) | |
235 | ||
1da177e4 LT |
236 | /* NOTE: fn is as per module_param, not __setup! Emits warning if fn |
237 | * returns non-zero. */ | |
238 | #define early_param(str, fn) \ | |
239 | __setup_param(str, fn, fn, 1) | |
240 | ||
30d7e0d4 | 241 | /* Relies on boot_command_line being set */ |
1da177e4 | 242 | void __init parse_early_param(void); |
13977091 | 243 | void __init parse_early_options(char *cmdline); |
1da177e4 LT |
244 | #endif /* __ASSEMBLY__ */ |
245 | ||
246 | /** | |
247 | * module_init() - driver initialization entry point | |
248 | * @x: function to be run at kernel boot time or module insertion | |
249 | * | |
72fd4a35 | 250 | * module_init() will either be called during do_initcalls() (if |
1da177e4 LT |
251 | * builtin) or at module insertion time (if a module). There can only |
252 | * be one per module. | |
253 | */ | |
254 | #define module_init(x) __initcall(x); | |
255 | ||
256 | /** | |
257 | * module_exit() - driver exit entry point | |
258 | * @x: function to be run when driver is removed | |
259 | * | |
260 | * module_exit() will wrap the driver clean-up code | |
261 | * with cleanup_module() when used with rmmod when | |
262 | * the driver is a module. If the driver is statically | |
263 | * compiled into the kernel, module_exit() has no effect. | |
264 | * There can only be one per module. | |
265 | */ | |
266 | #define module_exit(x) __exitcall(x); | |
267 | ||
268 | #else /* MODULE */ | |
269 | ||
270 | /* Don't use these in modules, but some people do... */ | |
271 | #define core_initcall(fn) module_init(fn) | |
272 | #define postcore_initcall(fn) module_init(fn) | |
273 | #define arch_initcall(fn) module_init(fn) | |
274 | #define subsys_initcall(fn) module_init(fn) | |
275 | #define fs_initcall(fn) module_init(fn) | |
276 | #define device_initcall(fn) module_init(fn) | |
277 | #define late_initcall(fn) module_init(fn) | |
278 | ||
279 | #define security_initcall(fn) module_init(fn) | |
280 | ||
4500d067 | 281 | /* Each module must use one module_init(). */ |
1da177e4 LT |
282 | #define module_init(initfn) \ |
283 | static inline initcall_t __inittest(void) \ | |
284 | { return initfn; } \ | |
285 | int init_module(void) __attribute__((alias(#initfn))); | |
286 | ||
287 | /* This is only required if you want to be unloadable. */ | |
288 | #define module_exit(exitfn) \ | |
289 | static inline exitcall_t __exittest(void) \ | |
290 | { return exitfn; } \ | |
291 | void cleanup_module(void) __attribute__((alias(#exitfn))); | |
292 | ||
293 | #define __setup_param(str, unique_id, fn) /* nothing */ | |
1da177e4 | 294 | #define __setup(str, func) /* nothing */ |
1da177e4 LT |
295 | #endif |
296 | ||
ab3bfca7 | 297 | /* Data marked not to be saved by software suspend */ |
f3fe866d | 298 | #define __nosavedata __section(.data.nosave) |
1da177e4 LT |
299 | |
300 | /* This means "can be init if no module support, otherwise module load | |
301 | may call it." */ | |
302 | #ifdef CONFIG_MODULES | |
303 | #define __init_or_module | |
304 | #define __initdata_or_module | |
305 | #else | |
306 | #define __init_or_module __init | |
307 | #define __initdata_or_module __initdata | |
308 | #endif /*CONFIG_MODULES*/ | |
309 | ||
1da177e4 LT |
310 | /* Functions marked as __devexit may be discarded at kernel link time, depending |
311 | on config options. Newer versions of binutils detect references from | |
312 | retained sections to discarded sections and flag an error. Pointers to | |
313 | __devexit functions must use __devexit_p(function_name), the wrapper will | |
314 | insert either the function_name or NULL, depending on the config options. | |
315 | */ | |
316 | #if defined(MODULE) || defined(CONFIG_HOTPLUG) | |
317 | #define __devexit_p(x) x | |
318 | #else | |
319 | #define __devexit_p(x) NULL | |
320 | #endif | |
321 | ||
322 | #ifdef MODULE | |
323 | #define __exit_p(x) x | |
324 | #else | |
325 | #define __exit_p(x) NULL | |
326 | #endif | |
327 | ||
328 | #endif /* _LINUX_INIT_H */ |