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1 | #ifndef _LINUX_INIT_H |
2 | #define _LINUX_INIT_H | |
3 | ||
4 | #include <linux/config.h> | |
5 | #include <linux/compiler.h> | |
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; | |
33 | * static char linux_logo[] __initdata = { 0x32, 0x36, ... }; | |
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) */ | |
44 | #define __init __attribute__ ((__section__ (".init.text"))) | |
45 | #define __initdata __attribute__ ((__section__ (".init.data"))) | |
46 | #define __exitdata __attribute__ ((__section__(".exit.data"))) | |
47 | #define __exit_call __attribute_used__ __attribute__ ((__section__ (".exitcall.exit"))) | |
48 | ||
49 | #ifdef MODULE | |
50 | #define __exit __attribute__ ((__section__(".exit.text"))) | |
51 | #else | |
52 | #define __exit __attribute_used__ __attribute__ ((__section__(".exit.text"))) | |
53 | #endif | |
54 | ||
55 | /* For assembly routines */ | |
56 | #define __INIT .section ".init.text","ax" | |
57 | #define __FINIT .previous | |
58 | #define __INITDATA .section ".init.data","aw" | |
59 | ||
60 | #ifndef __ASSEMBLY__ | |
61 | /* | |
62 | * Used for initialization calls.. | |
63 | */ | |
64 | typedef int (*initcall_t)(void); | |
65 | typedef void (*exitcall_t)(void); | |
66 | ||
67 | extern initcall_t __con_initcall_start[], __con_initcall_end[]; | |
68 | extern initcall_t __security_initcall_start[], __security_initcall_end[]; | |
69 | ||
70 | /* Defined in init/main.c */ | |
71 | extern char saved_command_line[]; | |
72 | #endif | |
73 | ||
74 | #ifndef MODULE | |
75 | ||
76 | #ifndef __ASSEMBLY__ | |
77 | ||
78 | /* initcalls are now grouped by functionality into separate | |
79 | * subsections. Ordering inside the subsections is determined | |
80 | * by link order. | |
81 | * For backwards compatibility, initcall() puts the call in | |
82 | * the device init subsection. | |
83 | */ | |
84 | ||
85 | #define __define_initcall(level,fn) \ | |
86 | static initcall_t __initcall_##fn __attribute_used__ \ | |
87 | __attribute__((__section__(".initcall" level ".init"))) = fn | |
88 | ||
89 | #define core_initcall(fn) __define_initcall("1",fn) | |
90 | #define postcore_initcall(fn) __define_initcall("2",fn) | |
91 | #define arch_initcall(fn) __define_initcall("3",fn) | |
92 | #define subsys_initcall(fn) __define_initcall("4",fn) | |
93 | #define fs_initcall(fn) __define_initcall("5",fn) | |
94 | #define device_initcall(fn) __define_initcall("6",fn) | |
95 | #define late_initcall(fn) __define_initcall("7",fn) | |
96 | ||
97 | #define __initcall(fn) device_initcall(fn) | |
98 | ||
99 | #define __exitcall(fn) \ | |
100 | static exitcall_t __exitcall_##fn __exit_call = fn | |
101 | ||
102 | #define console_initcall(fn) \ | |
103 | static initcall_t __initcall_##fn \ | |
104 | __attribute_used__ __attribute__((__section__(".con_initcall.init")))=fn | |
105 | ||
106 | #define security_initcall(fn) \ | |
107 | static initcall_t __initcall_##fn \ | |
108 | __attribute_used__ __attribute__((__section__(".security_initcall.init"))) = fn | |
109 | ||
110 | struct obs_kernel_param { | |
111 | const char *str; | |
112 | int (*setup_func)(char *); | |
113 | int early; | |
114 | }; | |
115 | ||
116 | /* | |
117 | * Only for really core code. See moduleparam.h for the normal way. | |
118 | * | |
119 | * Force the alignment so the compiler doesn't space elements of the | |
120 | * obs_kernel_param "array" too far apart in .init.setup. | |
121 | */ | |
122 | #define __setup_param(str, unique_id, fn, early) \ | |
123 | static char __setup_str_##unique_id[] __initdata = str; \ | |
124 | static struct obs_kernel_param __setup_##unique_id \ | |
125 | __attribute_used__ \ | |
126 | __attribute__((__section__(".init.setup"))) \ | |
127 | __attribute__((aligned((sizeof(long))))) \ | |
128 | = { __setup_str_##unique_id, fn, early } | |
129 | ||
130 | #define __setup_null_param(str, unique_id) \ | |
131 | __setup_param(str, unique_id, NULL, 0) | |
132 | ||
133 | #define __setup(str, fn) \ | |
134 | __setup_param(str, fn, fn, 0) | |
135 | ||
136 | #define __obsolete_setup(str) \ | |
137 | __setup_null_param(str, __LINE__) | |
138 | ||
139 | /* NOTE: fn is as per module_param, not __setup! Emits warning if fn | |
140 | * returns non-zero. */ | |
141 | #define early_param(str, fn) \ | |
142 | __setup_param(str, fn, fn, 1) | |
143 | ||
144 | /* Relies on saved_command_line being set */ | |
145 | void __init parse_early_param(void); | |
146 | #endif /* __ASSEMBLY__ */ | |
147 | ||
148 | /** | |
149 | * module_init() - driver initialization entry point | |
150 | * @x: function to be run at kernel boot time or module insertion | |
151 | * | |
152 | * module_init() will either be called during do_initcalls (if | |
153 | * builtin) or at module insertion time (if a module). There can only | |
154 | * be one per module. | |
155 | */ | |
156 | #define module_init(x) __initcall(x); | |
157 | ||
158 | /** | |
159 | * module_exit() - driver exit entry point | |
160 | * @x: function to be run when driver is removed | |
161 | * | |
162 | * module_exit() will wrap the driver clean-up code | |
163 | * with cleanup_module() when used with rmmod when | |
164 | * the driver is a module. If the driver is statically | |
165 | * compiled into the kernel, module_exit() has no effect. | |
166 | * There can only be one per module. | |
167 | */ | |
168 | #define module_exit(x) __exitcall(x); | |
169 | ||
170 | #else /* MODULE */ | |
171 | ||
172 | /* Don't use these in modules, but some people do... */ | |
173 | #define core_initcall(fn) module_init(fn) | |
174 | #define postcore_initcall(fn) module_init(fn) | |
175 | #define arch_initcall(fn) module_init(fn) | |
176 | #define subsys_initcall(fn) module_init(fn) | |
177 | #define fs_initcall(fn) module_init(fn) | |
178 | #define device_initcall(fn) module_init(fn) | |
179 | #define late_initcall(fn) module_init(fn) | |
180 | ||
181 | #define security_initcall(fn) module_init(fn) | |
182 | ||
183 | /* These macros create a dummy inline: gcc 2.9x does not count alias | |
184 | as usage, hence the `unused function' warning when __init functions | |
185 | are declared static. We use the dummy __*_module_inline functions | |
186 | both to kill the warning and check the type of the init/cleanup | |
187 | function. */ | |
188 | ||
189 | /* Each module must use one module_init(), or one no_module_init */ | |
190 | #define module_init(initfn) \ | |
191 | static inline initcall_t __inittest(void) \ | |
192 | { return initfn; } \ | |
193 | int init_module(void) __attribute__((alias(#initfn))); | |
194 | ||
195 | /* This is only required if you want to be unloadable. */ | |
196 | #define module_exit(exitfn) \ | |
197 | static inline exitcall_t __exittest(void) \ | |
198 | { return exitfn; } \ | |
199 | void cleanup_module(void) __attribute__((alias(#exitfn))); | |
200 | ||
201 | #define __setup_param(str, unique_id, fn) /* nothing */ | |
202 | #define __setup_null_param(str, unique_id) /* nothing */ | |
203 | #define __setup(str, func) /* nothing */ | |
204 | #define __obsolete_setup(str) /* nothing */ | |
205 | #endif | |
206 | ||
207 | /* Data marked not to be saved by software_suspend() */ | |
208 | #define __nosavedata __attribute__ ((__section__ (".data.nosave"))) | |
209 | ||
210 | /* This means "can be init if no module support, otherwise module load | |
211 | may call it." */ | |
212 | #ifdef CONFIG_MODULES | |
213 | #define __init_or_module | |
214 | #define __initdata_or_module | |
215 | #else | |
216 | #define __init_or_module __init | |
217 | #define __initdata_or_module __initdata | |
218 | #endif /*CONFIG_MODULES*/ | |
219 | ||
220 | #ifdef CONFIG_HOTPLUG | |
221 | #define __devinit | |
222 | #define __devinitdata | |
223 | #define __devexit | |
224 | #define __devexitdata | |
225 | #else | |
226 | #define __devinit __init | |
227 | #define __devinitdata __initdata | |
228 | #define __devexit __exit | |
229 | #define __devexitdata __exitdata | |
230 | #endif | |
231 | ||
e6982c67 AR |
232 | #ifdef CONFIG_HOTPLUG_CPU |
233 | #define __cpuinit | |
234 | #define __cpuinitdata | |
235 | #define __cpuexit | |
236 | #define __cpuexitdata | |
237 | #else | |
238 | #define __cpuinit __init | |
239 | #define __cpuinitdata __initdata | |
240 | #define __cpuexit __exit | |
241 | #define __cpuexitdata __exitdata | |
242 | #endif | |
243 | ||
1da177e4 LT |
244 | /* Functions marked as __devexit may be discarded at kernel link time, depending |
245 | on config options. Newer versions of binutils detect references from | |
246 | retained sections to discarded sections and flag an error. Pointers to | |
247 | __devexit functions must use __devexit_p(function_name), the wrapper will | |
248 | insert either the function_name or NULL, depending on the config options. | |
249 | */ | |
250 | #if defined(MODULE) || defined(CONFIG_HOTPLUG) | |
251 | #define __devexit_p(x) x | |
252 | #else | |
253 | #define __devexit_p(x) NULL | |
254 | #endif | |
255 | ||
256 | #ifdef MODULE | |
257 | #define __exit_p(x) x | |
258 | #else | |
259 | #define __exit_p(x) NULL | |
260 | #endif | |
261 | ||
262 | #endif /* _LINUX_INIT_H */ |