4 #include <linux/compiler.h>
5 #include <linux/types.h>
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
16 * You should add __init immediately before the function name, like:
18 * static void __init initme(int x, int y)
20 * extern int z; z = x * y;
23 * If the function has a prototype somewhere, you can also add
24 * __init between closing brace of the prototype and semicolon:
26 * extern int initialize_foobar_device(int, int, int) __init;
28 * For initialized data:
29 * You should insert __initdata between the variable name and equal
30 * sign followed by value, e.g.:
32 * static int init_variable __initdata = 0;
33 * static const char linux_logo[] __initconst = { 0x32, 0x36, ... };
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
39 * Also note, that this data cannot be "const".
42 /* These are for everybody (although not all archs will actually
43 discard it in modules) */
44 #define __init __section(.init.text) __cold notrace
45 #define __initdata __section(.init.data)
46 #define __initconst __section(.init.rodata)
47 #define __exitdata __section(.exit.data)
48 #define __exit_call __used __section(.exitcall.exit)
51 * modpost check for section mismatches during the kernel build.
52 * A section mismatch happens when there are references from a
53 * code or data section to an init section (both code or data).
54 * The init sections are (for most archs) discarded by the kernel
55 * when early init has completed so all such references are potential bugs.
56 * For exit sections the same issue exists.
58 * The following markers are used for the cases where the reference to
59 * the *init / *exit section (code or data) is valid and will teach
60 * modpost not to issue a warning. Intended semantics is that a code or
61 * data tagged __ref* can reference code or data from init section without
62 * producing a warning (of course, no warning does not mean code is
63 * correct, so optimally document why the __ref is needed and why it's OK).
65 * The markers follow same syntax rules as __init / __initdata.
67 #define __ref __section(.ref.text) noinline
68 #define __refdata __section(.ref.data)
69 #define __refconst __section(.ref.rodata)
71 /* compatibility defines */
72 #define __init_refok __ref
73 #define __initdata_refok __refdata
74 #define __exit_refok __ref
80 #define __exitused __used
83 #define __exit __section(.exit.text) __exitused __cold notrace
85 /* Used for HOTPLUG */
86 #define __devinit __section(.devinit.text) __cold notrace
87 #define __devinitdata __section(.devinit.data)
88 #define __devinitconst __section(.devinit.rodata)
89 #define __devexit __section(.devexit.text) __exitused __cold notrace
90 #define __devexitdata __section(.devexit.data)
91 #define __devexitconst __section(.devexit.rodata)
93 /* Used for HOTPLUG_CPU */
94 #define __cpuinit __section(.cpuinit.text) __cold notrace
95 #define __cpuinitdata __section(.cpuinit.data)
96 #define __cpuinitconst __section(.cpuinit.rodata)
97 #define __cpuexit __section(.cpuexit.text) __exitused __cold notrace
98 #define __cpuexitdata __section(.cpuexit.data)
99 #define __cpuexitconst __section(.cpuexit.rodata)
101 /* Used for MEMORY_HOTPLUG */
102 #define __meminit __section(.meminit.text) __cold notrace
103 #define __meminitdata __section(.meminit.data)
104 #define __meminitconst __section(.meminit.rodata)
105 #define __memexit __section(.memexit.text) __exitused __cold notrace
106 #define __memexitdata __section(.memexit.data)
107 #define __memexitconst __section(.memexit.rodata)
109 /* For assembly routines */
110 #define __HEAD .section ".head.text","ax"
111 #define __INIT .section ".init.text","ax"
112 #define __FINIT .previous
114 #define __INITDATA .section ".init.data","aw",%progbits
115 #define __INITRODATA .section ".init.rodata","a",%progbits
116 #define __FINITDATA .previous
118 #define __DEVINIT .section ".devinit.text", "ax"
119 #define __DEVINITDATA .section ".devinit.data", "aw"
120 #define __DEVINITRODATA .section ".devinit.rodata", "a"
122 #define __CPUINIT .section ".cpuinit.text", "ax"
123 #define __CPUINITDATA .section ".cpuinit.data", "aw"
124 #define __CPUINITRODATA .section ".cpuinit.rodata", "a"
126 #define __MEMINIT .section ".meminit.text", "ax"
127 #define __MEMINITDATA .section ".meminit.data", "aw"
128 #define __MEMINITRODATA .section ".meminit.rodata", "a"
130 /* silence warnings when references are OK */
131 #define __REF .section ".ref.text", "ax"
132 #define __REFDATA .section ".ref.data", "aw"
133 #define __REFCONST .section ".ref.rodata", "a"
137 * Used for initialization calls..
139 typedef int (*initcall_t
)(void);
140 typedef void (*exitcall_t
)(void);
142 extern initcall_t __con_initcall_start
[], __con_initcall_end
[];
143 extern initcall_t __security_initcall_start
[], __security_initcall_end
[];
145 /* Used for contructor calls. */
146 typedef void (*ctor_fn_t
)(void);
148 /* Defined in init/main.c */
149 extern int do_one_initcall(initcall_t fn
);
150 extern char __initdata boot_command_line
[];
151 extern char *saved_command_line
;
152 extern unsigned int reset_devices
;
154 /* used by init/main.c */
155 void setup_arch(char **);
156 void prepare_namespace(void);
158 extern void (*late_time_init
)(void);
160 extern bool initcall_debug
;
168 /* initcalls are now grouped by functionality into separate
169 * subsections. Ordering inside the subsections is determined
171 * For backwards compatibility, initcall() puts the call in
172 * the device init subsection.
174 * The `id' arg to __define_initcall() is needed so that multiple initcalls
175 * can point at the same handler without causing duplicate-symbol build errors.
178 #define __define_initcall(level,fn,id) \
179 static initcall_t __initcall_##fn##id __used \
180 __attribute__((__section__(".initcall" level ".init"))) = fn
183 * Early initcalls run before initializing SMP.
185 * Only for built-in code, not modules.
187 #define early_initcall(fn) __define_initcall("early",fn,early)
190 * A "pure" initcall has no dependencies on anything else, and purely
191 * initializes variables that couldn't be statically initialized.
193 * This only exists for built-in code, not for modules.
195 #define pure_initcall(fn) __define_initcall("0",fn,0)
197 #define core_initcall(fn) __define_initcall("1",fn,1)
198 #define core_initcall_sync(fn) __define_initcall("1s",fn,1s)
199 #define postcore_initcall(fn) __define_initcall("2",fn,2)
200 #define postcore_initcall_sync(fn) __define_initcall("2s",fn,2s)
201 #define arch_initcall(fn) __define_initcall("3",fn,3)
202 #define arch_initcall_sync(fn) __define_initcall("3s",fn,3s)
203 #define subsys_initcall(fn) __define_initcall("4",fn,4)
204 #define subsys_initcall_sync(fn) __define_initcall("4s",fn,4s)
205 #define fs_initcall(fn) __define_initcall("5",fn,5)
206 #define fs_initcall_sync(fn) __define_initcall("5s",fn,5s)
207 #define rootfs_initcall(fn) __define_initcall("rootfs",fn,rootfs)
208 #define device_initcall(fn) __define_initcall("6",fn,6)
209 #define device_initcall_sync(fn) __define_initcall("6s",fn,6s)
210 #define late_initcall(fn) __define_initcall("7",fn,7)
211 #define late_initcall_sync(fn) __define_initcall("7s",fn,7s)
213 #define __initcall(fn) device_initcall(fn)
215 #define __exitcall(fn) \
216 static exitcall_t __exitcall_##fn __exit_call = fn
218 #define console_initcall(fn) \
219 static initcall_t __initcall_##fn \
220 __used __section(.con_initcall.init) = fn
222 #define security_initcall(fn) \
223 static initcall_t __initcall_##fn \
224 __used __section(.security_initcall.init) = fn
226 struct obs_kernel_param
{
228 int (*setup_func
)(char *);
233 * Only for really core code. See moduleparam.h for the normal way.
235 * Force the alignment so the compiler doesn't space elements of the
236 * obs_kernel_param "array" too far apart in .init.setup.
238 #define __setup_param(str, unique_id, fn, early) \
239 static const char __setup_str_##unique_id[] __initconst \
240 __aligned(1) = str; \
241 static struct obs_kernel_param __setup_##unique_id \
242 __used __section(.init.setup) \
243 __attribute__((aligned((sizeof(long))))) \
244 = { __setup_str_##unique_id, fn, early }
246 #define __setup(str, fn) \
247 __setup_param(str, fn, fn, 0)
249 /* NOTE: fn is as per module_param, not __setup! Emits warning if fn
250 * returns non-zero. */
251 #define early_param(str, fn) \
252 __setup_param(str, fn, fn, 1)
254 /* Relies on boot_command_line being set */
255 void __init
parse_early_param(void);
256 void __init
parse_early_options(char *cmdline
);
257 #endif /* __ASSEMBLY__ */
260 * module_init() - driver initialization entry point
261 * @x: function to be run at kernel boot time or module insertion
263 * module_init() will either be called during do_initcalls() (if
264 * builtin) or at module insertion time (if a module). There can only
267 #define module_init(x) __initcall(x);
270 * module_exit() - driver exit entry point
271 * @x: function to be run when driver is removed
273 * module_exit() will wrap the driver clean-up code
274 * with cleanup_module() when used with rmmod when
275 * the driver is a module. If the driver is statically
276 * compiled into the kernel, module_exit() has no effect.
277 * There can only be one per module.
279 #define module_exit(x) __exitcall(x);
283 /* Don't use these in modules, but some people do... */
284 #define early_initcall(fn) module_init(fn)
285 #define core_initcall(fn) module_init(fn)
286 #define postcore_initcall(fn) module_init(fn)
287 #define arch_initcall(fn) module_init(fn)
288 #define subsys_initcall(fn) module_init(fn)
289 #define fs_initcall(fn) module_init(fn)
290 #define device_initcall(fn) module_init(fn)
291 #define late_initcall(fn) module_init(fn)
293 #define security_initcall(fn) module_init(fn)
295 /* Each module must use one module_init(). */
296 #define module_init(initfn) \
297 static inline initcall_t __inittest(void) \
299 int init_module(void) __attribute__((alias(#initfn)));
301 /* This is only required if you want to be unloadable. */
302 #define module_exit(exitfn) \
303 static inline exitcall_t __exittest(void) \
305 void cleanup_module(void) __attribute__((alias(#exitfn)));
307 #define __setup_param(str, unique_id, fn) /* nothing */
308 #define __setup(str, func) /* nothing */
311 /* Data marked not to be saved by software suspend */
312 #define __nosavedata __section(.data..nosave)
314 /* This means "can be init if no module support, otherwise module load
316 #ifdef CONFIG_MODULES
317 #define __init_or_module
318 #define __initdata_or_module
319 #define __initconst_or_module
320 #define __INIT_OR_MODULE .text
321 #define __INITDATA_OR_MODULE .data
322 #define __INITRODATA_OR_MODULE .section ".rodata","a",%progbits
324 #define __init_or_module __init
325 #define __initdata_or_module __initdata
326 #define __initconst_or_module __initconst
327 #define __INIT_OR_MODULE __INIT
328 #define __INITDATA_OR_MODULE __INITDATA
329 #define __INITRODATA_OR_MODULE __INITRODATA
330 #endif /*CONFIG_MODULES*/
332 /* Functions marked as __devexit may be discarded at kernel link time, depending
333 on config options. Newer versions of binutils detect references from
334 retained sections to discarded sections and flag an error. Pointers to
335 __devexit functions must use __devexit_p(function_name), the wrapper will
336 insert either the function_name or NULL, depending on the config options.
338 #if defined(MODULE) || defined(CONFIG_HOTPLUG)
339 #define __devexit_p(x) x
341 #define __devexit_p(x) NULL
345 #define __exit_p(x) x
347 #define __exit_p(x) NULL
350 #endif /* _LINUX_INIT_H */