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1da177e4 LT |
1 | #ifndef _LINUX_INIT_H |
2 | #define _LINUX_INIT_H | |
3 | ||
1da177e4 | 4 | #include <linux/compiler.h> |
2329abfa | 5 | #include <linux/types.h> |
1da177e4 LT |
6 | |
7 | /* These macros are used to mark some functions or | |
8 | * initialized data (doesn't apply to uninitialized data) | |
9 | * as `initialization' functions. The kernel can take this | |
10 | * as hint that the function is used only during the initialization | |
11 | * phase and free up used memory resources after | |
12 | * | |
13 | * Usage: | |
14 | * For functions: | |
15 | * | |
16 | * You should add __init immediately before the function name, like: | |
17 | * | |
18 | * static void __init initme(int x, int y) | |
19 | * { | |
20 | * extern int z; z = x * y; | |
21 | * } | |
22 | * | |
23 | * If the function has a prototype somewhere, you can also add | |
24 | * __init between closing brace of the prototype and semicolon: | |
25 | * | |
26 | * extern int initialize_foobar_device(int, int, int) __init; | |
27 | * | |
28 | * For initialized data: | |
29 | * You should insert __initdata between the variable name and equal | |
30 | * sign followed by value, e.g.: | |
31 | * | |
32 | * static int init_variable __initdata = 0; | |
ae52bb23 | 33 | * static const char linux_logo[] __initconst = { 0x32, 0x36, ... }; |
1da177e4 LT |
34 | * |
35 | * Don't forget to initialize data not at file scope, i.e. within a function, | |
36 | * as gcc otherwise puts the data into the bss section and not into the init | |
37 | * section. | |
38 | * | |
39 | * Also note, that this data cannot be "const". | |
40 | */ | |
41 | ||
42 | /* These are for everybody (although not all archs will actually | |
43 | discard it in modules) */ | |
fed1939c | 44 | #define __init __section(.init.text) __cold notrace |
f3fe866d | 45 | #define __initdata __section(.init.data) |
754b7b63 | 46 | #define __initconst __constsection(.init.rodata) |
f3fe866d | 47 | #define __exitdata __section(.exit.data) |
3ff6eecc | 48 | #define __exit_call __used __section(.exitcall.exit) |
1da177e4 | 49 | |
754b7b63 AK |
50 | /* |
51 | * Some architecture have tool chains which do not handle rodata attributes | |
52 | * correctly. For those disable special sections for const, so that other | |
53 | * architectures can annotate correctly. | |
54 | */ | |
55 | #ifdef CONFIG_BROKEN_RODATA | |
56 | #define __constsection(x) | |
57 | #else | |
58 | #define __constsection(x) __section(x) | |
59 | #endif | |
60 | ||
5ea08178 MN |
61 | /* |
62 | * modpost check for section mismatches during the kernel build. | |
0e0d314e SR |
63 | * A section mismatch happens when there are references from a |
64 | * code or data section to an init section (both code or data). | |
65 | * The init sections are (for most archs) discarded by the kernel | |
66 | * when early init has completed so all such references are potential bugs. | |
67 | * For exit sections the same issue exists. | |
5ea08178 | 68 | * |
0e0d314e | 69 | * The following markers are used for the cases where the reference to |
312b1485 | 70 | * the *init / *exit section (code or data) is valid and will teach |
5ea08178 MN |
71 | * modpost not to issue a warning. Intended semantics is that a code or |
72 | * data tagged __ref* can reference code or data from init section without | |
73 | * producing a warning (of course, no warning does not mean code is | |
74 | * correct, so optimally document why the __ref is needed and why it's OK). | |
75 | * | |
76 | * The markers follow same syntax rules as __init / __initdata. | |
77 | */ | |
312b1485 SR |
78 | #define __ref __section(.ref.text) noinline |
79 | #define __refdata __section(.ref.data) | |
754b7b63 | 80 | #define __refconst __constsection(.ref.rodata) |
312b1485 | 81 | |
312b1485 SR |
82 | /* compatibility defines */ |
83 | #define __init_refok __ref | |
84 | #define __initdata_refok __refdata | |
85 | #define __exit_refok __ref | |
86 | ||
0e0d314e | 87 | |
1da177e4 | 88 | #ifdef MODULE |
eb8f6890 | 89 | #define __exitused |
1da177e4 | 90 | #else |
eb8f6890 | 91 | #define __exitused __used |
1da177e4 LT |
92 | #endif |
93 | ||
f0201738 | 94 | #define __exit __section(.exit.text) __exitused __cold notrace |
eb8f6890 SR |
95 | |
96 | /* Used for HOTPLUG */ | |
f0201738 | 97 | #define __devinit __section(.devinit.text) __cold notrace |
eb8f6890 | 98 | #define __devinitdata __section(.devinit.data) |
754b7b63 | 99 | #define __devinitconst __constsection(.devinit.rodata) |
f0201738 | 100 | #define __devexit __section(.devexit.text) __exitused __cold notrace |
eb8f6890 | 101 | #define __devexitdata __section(.devexit.data) |
754b7b63 | 102 | #define __devexitconst __constsection(.devexit.rodata) |
eb8f6890 SR |
103 | |
104 | /* Used for HOTPLUG_CPU */ | |
f0201738 | 105 | #define __cpuinit __section(.cpuinit.text) __cold notrace |
eb8f6890 | 106 | #define __cpuinitdata __section(.cpuinit.data) |
754b7b63 | 107 | #define __cpuinitconst __constsection(.cpuinit.rodata) |
f0201738 | 108 | #define __cpuexit __section(.cpuexit.text) __exitused __cold notrace |
eb8f6890 | 109 | #define __cpuexitdata __section(.cpuexit.data) |
754b7b63 | 110 | #define __cpuexitconst __constsection(.cpuexit.rodata) |
eb8f6890 SR |
111 | |
112 | /* Used for MEMORY_HOTPLUG */ | |
f0201738 | 113 | #define __meminit __section(.meminit.text) __cold notrace |
eb8f6890 | 114 | #define __meminitdata __section(.meminit.data) |
754b7b63 | 115 | #define __meminitconst __constsection(.meminit.rodata) |
f0201738 | 116 | #define __memexit __section(.memexit.text) __exitused __cold notrace |
eb8f6890 | 117 | #define __memexitdata __section(.memexit.data) |
754b7b63 | 118 | #define __memexitconst __constsection(.memexit.rodata) |
eb8f6890 | 119 | |
1da177e4 | 120 | /* For assembly routines */ |
7923f90f | 121 | #define __HEAD .section ".head.text","ax" |
1da177e4 | 122 | #define __INIT .section ".init.text","ax" |
86c0baf1 | 123 | #define __FINIT .previous |
eb8f6890 | 124 | |
8b5a10fc JB |
125 | #define __INITDATA .section ".init.data","aw",%progbits |
126 | #define __INITRODATA .section ".init.rodata","a",%progbits | |
9f9975a5 | 127 | #define __FINITDATA .previous |
1da177e4 | 128 | |
eb8f6890 SR |
129 | #define __DEVINIT .section ".devinit.text", "ax" |
130 | #define __DEVINITDATA .section ".devinit.data", "aw" | |
3f5e26ce | 131 | #define __DEVINITRODATA .section ".devinit.rodata", "a" |
eb8f6890 SR |
132 | |
133 | #define __CPUINIT .section ".cpuinit.text", "ax" | |
134 | #define __CPUINITDATA .section ".cpuinit.data", "aw" | |
3f5e26ce | 135 | #define __CPUINITRODATA .section ".cpuinit.rodata", "a" |
eb8f6890 SR |
136 | |
137 | #define __MEMINIT .section ".meminit.text", "ax" | |
138 | #define __MEMINITDATA .section ".meminit.data", "aw" | |
3f5e26ce | 139 | #define __MEMINITRODATA .section ".meminit.rodata", "a" |
eb8f6890 | 140 | |
312b1485 SR |
141 | /* silence warnings when references are OK */ |
142 | #define __REF .section ".ref.text", "ax" | |
143 | #define __REFDATA .section ".ref.data", "aw" | |
3f5e26ce | 144 | #define __REFCONST .section ".ref.rodata", "a" |
312b1485 | 145 | |
1da177e4 LT |
146 | #ifndef __ASSEMBLY__ |
147 | /* | |
148 | * Used for initialization calls.. | |
149 | */ | |
150 | typedef int (*initcall_t)(void); | |
151 | typedef void (*exitcall_t)(void); | |
152 | ||
153 | extern initcall_t __con_initcall_start[], __con_initcall_end[]; | |
154 | extern initcall_t __security_initcall_start[], __security_initcall_end[]; | |
155 | ||
b99b87f7 PO |
156 | /* Used for contructor calls. */ |
157 | typedef void (*ctor_fn_t)(void); | |
158 | ||
1da177e4 | 159 | /* Defined in init/main.c */ |
59f9415f | 160 | extern int do_one_initcall(initcall_t fn); |
30d7e0d4 ABL |
161 | extern char __initdata boot_command_line[]; |
162 | extern char *saved_command_line; | |
7e96287d | 163 | extern unsigned int reset_devices; |
77d47582 AB |
164 | |
165 | /* used by init/main.c */ | |
46595390 AB |
166 | void setup_arch(char **); |
167 | void prepare_namespace(void); | |
77d47582 | 168 | |
7d195a54 AB |
169 | extern void (*late_time_init)(void); |
170 | ||
2329abfa | 171 | extern bool initcall_debug; |
f2511774 | 172 | |
1da177e4 LT |
173 | #endif |
174 | ||
175 | #ifndef MODULE | |
176 | ||
177 | #ifndef __ASSEMBLY__ | |
178 | ||
179 | /* initcalls are now grouped by functionality into separate | |
180 | * subsections. Ordering inside the subsections is determined | |
181 | * by link order. | |
182 | * For backwards compatibility, initcall() puts the call in | |
183 | * the device init subsection. | |
735a7ffb AM |
184 | * |
185 | * The `id' arg to __define_initcall() is needed so that multiple initcalls | |
186 | * can point at the same handler without causing duplicate-symbol build errors. | |
1da177e4 LT |
187 | */ |
188 | ||
735a7ffb | 189 | #define __define_initcall(level,fn,id) \ |
3ff6eecc | 190 | static initcall_t __initcall_##fn##id __used \ |
1da177e4 LT |
191 | __attribute__((__section__(".initcall" level ".init"))) = fn |
192 | ||
c2147a50 EGM |
193 | /* |
194 | * Early initcalls run before initializing SMP. | |
195 | * | |
196 | * Only for built-in code, not modules. | |
197 | */ | |
198 | #define early_initcall(fn) __define_initcall("early",fn,early) | |
199 | ||
b3438f82 LT |
200 | /* |
201 | * A "pure" initcall has no dependencies on anything else, and purely | |
202 | * initializes variables that couldn't be statically initialized. | |
203 | * | |
204 | * This only exists for built-in code, not for modules. | |
96263d28 | 205 | * Keep main.c:initcall_level_names[] in sync. |
b3438f82 | 206 | */ |
73dd1166 | 207 | #define pure_initcall(fn) __define_initcall("0",fn,0) |
b3438f82 | 208 | |
735a7ffb AM |
209 | #define core_initcall(fn) __define_initcall("1",fn,1) |
210 | #define core_initcall_sync(fn) __define_initcall("1s",fn,1s) | |
211 | #define postcore_initcall(fn) __define_initcall("2",fn,2) | |
212 | #define postcore_initcall_sync(fn) __define_initcall("2s",fn,2s) | |
213 | #define arch_initcall(fn) __define_initcall("3",fn,3) | |
214 | #define arch_initcall_sync(fn) __define_initcall("3s",fn,3s) | |
215 | #define subsys_initcall(fn) __define_initcall("4",fn,4) | |
216 | #define subsys_initcall_sync(fn) __define_initcall("4s",fn,4s) | |
217 | #define fs_initcall(fn) __define_initcall("5",fn,5) | |
218 | #define fs_initcall_sync(fn) __define_initcall("5s",fn,5s) | |
8d610dd5 | 219 | #define rootfs_initcall(fn) __define_initcall("rootfs",fn,rootfs) |
735a7ffb AM |
220 | #define device_initcall(fn) __define_initcall("6",fn,6) |
221 | #define device_initcall_sync(fn) __define_initcall("6s",fn,6s) | |
222 | #define late_initcall(fn) __define_initcall("7",fn,7) | |
223 | #define late_initcall_sync(fn) __define_initcall("7s",fn,7s) | |
1da177e4 LT |
224 | |
225 | #define __initcall(fn) device_initcall(fn) | |
226 | ||
227 | #define __exitcall(fn) \ | |
228 | static exitcall_t __exitcall_##fn __exit_call = fn | |
229 | ||
230 | #define console_initcall(fn) \ | |
231 | static initcall_t __initcall_##fn \ | |
3ff6eecc | 232 | __used __section(.con_initcall.init) = fn |
1da177e4 LT |
233 | |
234 | #define security_initcall(fn) \ | |
235 | static initcall_t __initcall_##fn \ | |
3ff6eecc | 236 | __used __section(.security_initcall.init) = fn |
1da177e4 LT |
237 | |
238 | struct obs_kernel_param { | |
239 | const char *str; | |
240 | int (*setup_func)(char *); | |
241 | int early; | |
242 | }; | |
243 | ||
244 | /* | |
245 | * Only for really core code. See moduleparam.h for the normal way. | |
246 | * | |
247 | * Force the alignment so the compiler doesn't space elements of the | |
248 | * obs_kernel_param "array" too far apart in .init.setup. | |
249 | */ | |
250 | #define __setup_param(str, unique_id, fn, early) \ | |
fd6c3a8d JB |
251 | static const char __setup_str_##unique_id[] __initconst \ |
252 | __aligned(1) = str; \ | |
1da177e4 | 253 | static struct obs_kernel_param __setup_##unique_id \ |
3ff6eecc | 254 | __used __section(.init.setup) \ |
1da177e4 LT |
255 | __attribute__((aligned((sizeof(long))))) \ |
256 | = { __setup_str_##unique_id, fn, early } | |
257 | ||
1da177e4 LT |
258 | #define __setup(str, fn) \ |
259 | __setup_param(str, fn, fn, 0) | |
260 | ||
1da177e4 LT |
261 | /* NOTE: fn is as per module_param, not __setup! Emits warning if fn |
262 | * returns non-zero. */ | |
263 | #define early_param(str, fn) \ | |
264 | __setup_param(str, fn, fn, 1) | |
265 | ||
30d7e0d4 | 266 | /* Relies on boot_command_line being set */ |
1da177e4 | 267 | void __init parse_early_param(void); |
13977091 | 268 | void __init parse_early_options(char *cmdline); |
1da177e4 LT |
269 | #endif /* __ASSEMBLY__ */ |
270 | ||
271 | /** | |
272 | * module_init() - driver initialization entry point | |
273 | * @x: function to be run at kernel boot time or module insertion | |
274 | * | |
72fd4a35 | 275 | * module_init() will either be called during do_initcalls() (if |
1da177e4 LT |
276 | * builtin) or at module insertion time (if a module). There can only |
277 | * be one per module. | |
278 | */ | |
279 | #define module_init(x) __initcall(x); | |
280 | ||
281 | /** | |
282 | * module_exit() - driver exit entry point | |
283 | * @x: function to be run when driver is removed | |
284 | * | |
285 | * module_exit() will wrap the driver clean-up code | |
286 | * with cleanup_module() when used with rmmod when | |
287 | * the driver is a module. If the driver is statically | |
288 | * compiled into the kernel, module_exit() has no effect. | |
289 | * There can only be one per module. | |
290 | */ | |
291 | #define module_exit(x) __exitcall(x); | |
292 | ||
293 | #else /* MODULE */ | |
294 | ||
96263d28 | 295 | /* Don't use these in loadable modules, but some people do... */ |
329bd411 | 296 | #define early_initcall(fn) module_init(fn) |
1da177e4 LT |
297 | #define core_initcall(fn) module_init(fn) |
298 | #define postcore_initcall(fn) module_init(fn) | |
299 | #define arch_initcall(fn) module_init(fn) | |
300 | #define subsys_initcall(fn) module_init(fn) | |
301 | #define fs_initcall(fn) module_init(fn) | |
302 | #define device_initcall(fn) module_init(fn) | |
303 | #define late_initcall(fn) module_init(fn) | |
304 | ||
305 | #define security_initcall(fn) module_init(fn) | |
306 | ||
4500d067 | 307 | /* Each module must use one module_init(). */ |
1da177e4 LT |
308 | #define module_init(initfn) \ |
309 | static inline initcall_t __inittest(void) \ | |
310 | { return initfn; } \ | |
311 | int init_module(void) __attribute__((alias(#initfn))); | |
312 | ||
313 | /* This is only required if you want to be unloadable. */ | |
314 | #define module_exit(exitfn) \ | |
315 | static inline exitcall_t __exittest(void) \ | |
316 | { return exitfn; } \ | |
317 | void cleanup_module(void) __attribute__((alias(#exitfn))); | |
318 | ||
319 | #define __setup_param(str, unique_id, fn) /* nothing */ | |
1da177e4 | 320 | #define __setup(str, func) /* nothing */ |
1da177e4 LT |
321 | #endif |
322 | ||
ab3bfca7 | 323 | /* Data marked not to be saved by software suspend */ |
07b3bb1e | 324 | #define __nosavedata __section(.data..nosave) |
1da177e4 LT |
325 | |
326 | /* This means "can be init if no module support, otherwise module load | |
327 | may call it." */ | |
328 | #ifdef CONFIG_MODULES | |
329 | #define __init_or_module | |
330 | #define __initdata_or_module | |
8b5a10fc JB |
331 | #define __initconst_or_module |
332 | #define __INIT_OR_MODULE .text | |
333 | #define __INITDATA_OR_MODULE .data | |
334 | #define __INITRODATA_OR_MODULE .section ".rodata","a",%progbits | |
1da177e4 LT |
335 | #else |
336 | #define __init_or_module __init | |
337 | #define __initdata_or_module __initdata | |
8b5a10fc JB |
338 | #define __initconst_or_module __initconst |
339 | #define __INIT_OR_MODULE __INIT | |
340 | #define __INITDATA_OR_MODULE __INITDATA | |
341 | #define __INITRODATA_OR_MODULE __INITRODATA | |
1da177e4 LT |
342 | #endif /*CONFIG_MODULES*/ |
343 | ||
1da177e4 LT |
344 | /* Functions marked as __devexit may be discarded at kernel link time, depending |
345 | on config options. Newer versions of binutils detect references from | |
346 | retained sections to discarded sections and flag an error. Pointers to | |
347 | __devexit functions must use __devexit_p(function_name), the wrapper will | |
348 | insert either the function_name or NULL, depending on the config options. | |
349 | */ | |
350 | #if defined(MODULE) || defined(CONFIG_HOTPLUG) | |
351 | #define __devexit_p(x) x | |
352 | #else | |
353 | #define __devexit_p(x) NULL | |
354 | #endif | |
355 | ||
356 | #ifdef MODULE | |
357 | #define __exit_p(x) x | |
358 | #else | |
359 | #define __exit_p(x) NULL | |
360 | #endif | |
361 | ||
362 | #endif /* _LINUX_INIT_H */ |