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 __constsection(.init.rodata)
47 #define __exitdata __section(.exit.data)
48 #define __exit_call __used __section(.exitcall.exit)
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.
55 #ifdef CONFIG_BROKEN_RODATA
56 #define __constsection(x)
58 #define __constsection(x) __section(x)
62 * modpost check for section mismatches during the kernel build.
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.
69 * The following markers are used for the cases where the reference to
70 * the *init / *exit section (code or data) is valid and will teach
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).
76 * The markers follow same syntax rules as __init / __initdata.
78 #define __ref __section(.ref.text) noinline
79 #define __refdata __section(.ref.data)
80 #define __refconst __constsection(.ref.rodata)
82 /* compatibility defines */
83 #define __init_refok __ref
84 #define __initdata_refok __refdata
85 #define __exit_refok __ref
91 #define __exitused __used
94 #define __exit __section(.exit.text) __exitused __cold notrace
96 /* Used for HOTPLUG, but that is always enabled now, so just make them noops */
99 #define __devinitconst
101 #define __devexitdata
102 #define __devexitconst
104 /* Used for HOTPLUG_CPU */
105 #define __cpuinit __section(.cpuinit.text) __cold notrace
106 #define __cpuinitdata __section(.cpuinit.data)
107 #define __cpuinitconst __constsection(.cpuinit.rodata)
108 #define __cpuexit __section(.cpuexit.text) __exitused __cold notrace
109 #define __cpuexitdata __section(.cpuexit.data)
110 #define __cpuexitconst __constsection(.cpuexit.rodata)
112 /* Used for MEMORY_HOTPLUG */
113 #define __meminit __section(.meminit.text) __cold notrace
114 #define __meminitdata __section(.meminit.data)
115 #define __meminitconst __constsection(.meminit.rodata)
116 #define __memexit __section(.memexit.text) __exitused __cold notrace
117 #define __memexitdata __section(.memexit.data)
118 #define __memexitconst __constsection(.memexit.rodata)
120 /* For assembly routines */
121 #define __HEAD .section ".head.text","ax"
122 #define __INIT .section ".init.text","ax"
123 #define __FINIT .previous
125 #define __INITDATA .section ".init.data","aw",%progbits
126 #define __INITRODATA .section ".init.rodata","a",%progbits
127 #define __FINITDATA .previous
129 #define __CPUINIT .section ".cpuinit.text", "ax"
130 #define __CPUINITDATA .section ".cpuinit.data", "aw"
131 #define __CPUINITRODATA .section ".cpuinit.rodata", "a"
133 #define __MEMINIT .section ".meminit.text", "ax"
134 #define __MEMINITDATA .section ".meminit.data", "aw"
135 #define __MEMINITRODATA .section ".meminit.rodata", "a"
137 /* silence warnings when references are OK */
138 #define __REF .section ".ref.text", "ax"
139 #define __REFDATA .section ".ref.data", "aw"
140 #define __REFCONST .section ".ref.rodata", "a"
144 * Used for initialization calls..
146 typedef int (*initcall_t
)(void);
147 typedef void (*exitcall_t
)(void);
149 extern initcall_t __con_initcall_start
[], __con_initcall_end
[];
150 extern initcall_t __security_initcall_start
[], __security_initcall_end
[];
152 /* Used for contructor calls. */
153 typedef void (*ctor_fn_t
)(void);
155 /* Defined in init/main.c */
156 extern int do_one_initcall(initcall_t fn
);
157 extern char __initdata boot_command_line
[];
158 extern char *saved_command_line
;
159 extern unsigned int reset_devices
;
161 /* used by init/main.c */
162 void setup_arch(char **);
163 void prepare_namespace(void);
165 extern void (*late_time_init
)(void);
167 extern bool initcall_debug
;
175 /* initcalls are now grouped by functionality into separate
176 * subsections. Ordering inside the subsections is determined
178 * For backwards compatibility, initcall() puts the call in
179 * the device init subsection.
181 * The `id' arg to __define_initcall() is needed so that multiple initcalls
182 * can point at the same handler without causing duplicate-symbol build errors.
185 #define __define_initcall(level,fn,id) \
186 static initcall_t __initcall_##fn##id __used \
187 __attribute__((__section__(".initcall" level ".init"))) = fn
190 * Early initcalls run before initializing SMP.
192 * Only for built-in code, not modules.
194 #define early_initcall(fn) __define_initcall("early",fn,early)
197 * A "pure" initcall has no dependencies on anything else, and purely
198 * initializes variables that couldn't be statically initialized.
200 * This only exists for built-in code, not for modules.
201 * Keep main.c:initcall_level_names[] in sync.
203 #define pure_initcall(fn) __define_initcall("0",fn,0)
205 #define core_initcall(fn) __define_initcall("1",fn,1)
206 #define core_initcall_sync(fn) __define_initcall("1s",fn,1s)
207 #define postcore_initcall(fn) __define_initcall("2",fn,2)
208 #define postcore_initcall_sync(fn) __define_initcall("2s",fn,2s)
209 #define arch_initcall(fn) __define_initcall("3",fn,3)
210 #define arch_initcall_sync(fn) __define_initcall("3s",fn,3s)
211 #define subsys_initcall(fn) __define_initcall("4",fn,4)
212 #define subsys_initcall_sync(fn) __define_initcall("4s",fn,4s)
213 #define fs_initcall(fn) __define_initcall("5",fn,5)
214 #define fs_initcall_sync(fn) __define_initcall("5s",fn,5s)
215 #define rootfs_initcall(fn) __define_initcall("rootfs",fn,rootfs)
216 #define device_initcall(fn) __define_initcall("6",fn,6)
217 #define device_initcall_sync(fn) __define_initcall("6s",fn,6s)
218 #define late_initcall(fn) __define_initcall("7",fn,7)
219 #define late_initcall_sync(fn) __define_initcall("7s",fn,7s)
221 #define __initcall(fn) device_initcall(fn)
223 #define __exitcall(fn) \
224 static exitcall_t __exitcall_##fn __exit_call = fn
226 #define console_initcall(fn) \
227 static initcall_t __initcall_##fn \
228 __used __section(.con_initcall.init) = fn
230 #define security_initcall(fn) \
231 static initcall_t __initcall_##fn \
232 __used __section(.security_initcall.init) = fn
234 struct obs_kernel_param
{
236 int (*setup_func
)(char *);
241 * Only for really core code. See moduleparam.h for the normal way.
243 * Force the alignment so the compiler doesn't space elements of the
244 * obs_kernel_param "array" too far apart in .init.setup.
246 #define __setup_param(str, unique_id, fn, early) \
247 static const char __setup_str_##unique_id[] __initconst \
248 __aligned(1) = str; \
249 static struct obs_kernel_param __setup_##unique_id \
250 __used __section(.init.setup) \
251 __attribute__((aligned((sizeof(long))))) \
252 = { __setup_str_##unique_id, fn, early }
254 #define __setup(str, fn) \
255 __setup_param(str, fn, fn, 0)
257 /* NOTE: fn is as per module_param, not __setup! Emits warning if fn
258 * returns non-zero. */
259 #define early_param(str, fn) \
260 __setup_param(str, fn, fn, 1)
262 /* Relies on boot_command_line being set */
263 void __init
parse_early_param(void);
264 void __init
parse_early_options(char *cmdline
);
265 #endif /* __ASSEMBLY__ */
268 * module_init() - driver initialization entry point
269 * @x: function to be run at kernel boot time or module insertion
271 * module_init() will either be called during do_initcalls() (if
272 * builtin) or at module insertion time (if a module). There can only
275 #define module_init(x) __initcall(x);
278 * module_exit() - driver exit entry point
279 * @x: function to be run when driver is removed
281 * module_exit() will wrap the driver clean-up code
282 * with cleanup_module() when used with rmmod when
283 * the driver is a module. If the driver is statically
284 * compiled into the kernel, module_exit() has no effect.
285 * There can only be one per module.
287 #define module_exit(x) __exitcall(x);
291 /* Don't use these in loadable modules, but some people do... */
292 #define early_initcall(fn) module_init(fn)
293 #define core_initcall(fn) module_init(fn)
294 #define postcore_initcall(fn) module_init(fn)
295 #define arch_initcall(fn) module_init(fn)
296 #define subsys_initcall(fn) module_init(fn)
297 #define fs_initcall(fn) module_init(fn)
298 #define device_initcall(fn) module_init(fn)
299 #define late_initcall(fn) module_init(fn)
301 #define security_initcall(fn) module_init(fn)
303 /* Each module must use one module_init(). */
304 #define module_init(initfn) \
305 static inline initcall_t __inittest(void) \
307 int init_module(void) __attribute__((alias(#initfn)));
309 /* This is only required if you want to be unloadable. */
310 #define module_exit(exitfn) \
311 static inline exitcall_t __exittest(void) \
313 void cleanup_module(void) __attribute__((alias(#exitfn)));
315 #define __setup_param(str, unique_id, fn) /* nothing */
316 #define __setup(str, func) /* nothing */
319 /* Data marked not to be saved by software suspend */
320 #define __nosavedata __section(.data..nosave)
322 /* This means "can be init if no module support, otherwise module load
324 #ifdef CONFIG_MODULES
325 #define __init_or_module
326 #define __initdata_or_module
327 #define __initconst_or_module
328 #define __INIT_OR_MODULE .text
329 #define __INITDATA_OR_MODULE .data
330 #define __INITRODATA_OR_MODULE .section ".rodata","a",%progbits
332 #define __init_or_module __init
333 #define __initdata_or_module __initdata
334 #define __initconst_or_module __initconst
335 #define __INIT_OR_MODULE __INIT
336 #define __INITDATA_OR_MODULE __INITDATA
337 #define __INITRODATA_OR_MODULE __INITRODATA
338 #endif /*CONFIG_MODULES*/
340 /* Functions marked as __devexit may be discarded at kernel link time, depending
341 on config options. Newer versions of binutils detect references from
342 retained sections to discarded sections and flag an error. Pointers to
343 __devexit functions must use __devexit_p(function_name), the wrapper will
344 insert either the function_name or NULL, depending on the config options.
346 #if defined(MODULE) || defined(CONFIG_HOTPLUG)
347 #define __devexit_p(x) x
349 #define __devexit_p(x) NULL
353 #define __exit_p(x) x
355 #define __exit_p(x) NULL
358 #endif /* _LINUX_INIT_H */