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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_INIT_H
2#define _LINUX_INIT_H
3
Linus Torvalds1da177e2005-04-16 15:20:36 -07004#include <linux/compiler.h>
Rusty Russell2329abf2012-01-13 09:32:18 +10305#include <linux/types.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07006
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;
Geert Uytterhoevenae52bb22009-06-16 15:34:19 -070033 * static const char linux_logo[] __initconst = { 0x32, 0x36, ... };
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 *
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) */
Steven Rostedtfed19392008-08-14 22:47:19 -040044#define __init __section(.init.text) __cold notrace
Sam Ravnborgf3fe8662008-01-20 18:54:48 +010045#define __initdata __section(.init.data)
Andi Kleen754b7b62012-10-04 17:11:27 -070046#define __initconst __constsection(.init.rodata)
Sam Ravnborgf3fe8662008-01-20 18:54:48 +010047#define __exitdata __section(.exit.data)
Adrian Bunk3ff6eec2008-01-24 22:16:20 +010048#define __exit_call __used __section(.exitcall.exit)
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
Michal Nazarewicz5ea08172010-08-12 17:43:56 +020050/*
Andi Kleen754b7b62012-10-04 17:11:27 -070051 * 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
61/*
Michal Nazarewicz5ea08172010-08-12 17:43:56 +020062 * modpost check for section mismatches during the kernel build.
Sam Ravnborg0e0d3142007-05-17 20:14:48 +020063 * 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.
Michal Nazarewicz5ea08172010-08-12 17:43:56 +020068 *
Sam Ravnborg0e0d3142007-05-17 20:14:48 +020069 * The following markers are used for the cases where the reference to
Sam Ravnborg312b1482008-01-28 20:21:15 +010070 * the *init / *exit section (code or data) is valid and will teach
Michal Nazarewicz5ea08172010-08-12 17:43:56 +020071 * 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 */
Sam Ravnborg312b1482008-01-28 20:21:15 +010078#define __ref __section(.ref.text) noinline
79#define __refdata __section(.ref.data)
Andi Kleen754b7b62012-10-04 17:11:27 -070080#define __refconst __constsection(.ref.rodata)
Sam Ravnborg312b1482008-01-28 20:21:15 +010081
Sam Ravnborg312b1482008-01-28 20:21:15 +010082/* compatibility defines */
83#define __init_refok __ref
84#define __initdata_refok __refdata
85#define __exit_refok __ref
86
Sam Ravnborg0e0d3142007-05-17 20:14:48 +020087
Linus Torvalds1da177e2005-04-16 15:20:36 -070088#ifdef MODULE
Sam Ravnborgeb8f6892008-01-20 20:07:28 +010089#define __exitused
Linus Torvalds1da177e2005-04-16 15:20:36 -070090#else
Sam Ravnborgeb8f6892008-01-20 20:07:28 +010091#define __exitused __used
Linus Torvalds1da177e2005-04-16 15:20:36 -070092#endif
93
Steven Rostedtf0201732011-04-12 19:06:39 -040094#define __exit __section(.exit.text) __exitused __cold notrace
Sam Ravnborgeb8f6892008-01-20 20:07:28 +010095
Sam Ravnborgeb8f6892008-01-20 20:07:28 +010096/* Used for HOTPLUG_CPU */
Steven Rostedtf0201732011-04-12 19:06:39 -040097#define __cpuinit __section(.cpuinit.text) __cold notrace
Sam Ravnborgeb8f6892008-01-20 20:07:28 +010098#define __cpuinitdata __section(.cpuinit.data)
Andi Kleen754b7b62012-10-04 17:11:27 -070099#define __cpuinitconst __constsection(.cpuinit.rodata)
Steven Rostedtf0201732011-04-12 19:06:39 -0400100#define __cpuexit __section(.cpuexit.text) __exitused __cold notrace
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100101#define __cpuexitdata __section(.cpuexit.data)
Andi Kleen754b7b62012-10-04 17:11:27 -0700102#define __cpuexitconst __constsection(.cpuexit.rodata)
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100103
104/* Used for MEMORY_HOTPLUG */
Steven Rostedtf0201732011-04-12 19:06:39 -0400105#define __meminit __section(.meminit.text) __cold notrace
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100106#define __meminitdata __section(.meminit.data)
Andi Kleen754b7b62012-10-04 17:11:27 -0700107#define __meminitconst __constsection(.meminit.rodata)
Steven Rostedtf0201732011-04-12 19:06:39 -0400108#define __memexit __section(.memexit.text) __exitused __cold notrace
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100109#define __memexitdata __section(.memexit.data)
Andi Kleen754b7b62012-10-04 17:11:27 -0700110#define __memexitconst __constsection(.memexit.rodata)
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100111
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112/* For assembly routines */
Sam Ravnborg7923f902009-06-14 22:10:41 +0200113#define __HEAD .section ".head.text","ax"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114#define __INIT .section ".init.text","ax"
Prarit Bhargava86c0baf2007-05-02 19:27:05 +0200115#define __FINIT .previous
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100116
Jan Beulich8b5a10f2009-08-19 08:40:48 +0100117#define __INITDATA .section ".init.data","aw",%progbits
118#define __INITRODATA .section ".init.rodata","a",%progbits
Ingo Molnar9f9975a2008-02-06 22:39:45 +0100119#define __FINITDATA .previous
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100121#define __CPUINIT .section ".cpuinit.text", "ax"
122#define __CPUINITDATA .section ".cpuinit.data", "aw"
Jan Beulich3f5e26c2008-10-25 15:02:51 -0700123#define __CPUINITRODATA .section ".cpuinit.rodata", "a"
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100124
125#define __MEMINIT .section ".meminit.text", "ax"
126#define __MEMINITDATA .section ".meminit.data", "aw"
Jan Beulich3f5e26c2008-10-25 15:02:51 -0700127#define __MEMINITRODATA .section ".meminit.rodata", "a"
Sam Ravnborgeb8f6892008-01-20 20:07:28 +0100128
Sam Ravnborg312b1482008-01-28 20:21:15 +0100129/* silence warnings when references are OK */
130#define __REF .section ".ref.text", "ax"
131#define __REFDATA .section ".ref.data", "aw"
Jan Beulich3f5e26c2008-10-25 15:02:51 -0700132#define __REFCONST .section ".ref.rodata", "a"
Sam Ravnborg312b1482008-01-28 20:21:15 +0100133
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134#ifndef __ASSEMBLY__
135/*
136 * Used for initialization calls..
137 */
138typedef int (*initcall_t)(void);
139typedef void (*exitcall_t)(void);
140
141extern initcall_t __con_initcall_start[], __con_initcall_end[];
142extern initcall_t __security_initcall_start[], __security_initcall_end[];
143
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -0700144/* Used for contructor calls. */
145typedef void (*ctor_fn_t)(void);
146
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147/* Defined in init/main.c */
Arjan van de Ven59f94152008-07-30 12:49:02 -0700148extern int do_one_initcall(initcall_t fn);
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800149extern char __initdata boot_command_line[];
150extern char *saved_command_line;
Vivek Goyal7e962872006-09-27 01:50:44 -0700151extern unsigned int reset_devices;
Adrian Bunk77d47582006-03-25 03:07:39 -0800152
153/* used by init/main.c */
Adrian Bunk46595392007-05-08 00:24:47 -0700154void setup_arch(char **);
155void prepare_namespace(void);
Adrian Bunk77d47582006-03-25 03:07:39 -0800156
Adrian Bunk7d195a52008-04-29 00:59:18 -0700157extern void (*late_time_init)(void);
158
Rusty Russell2329abf2012-01-13 09:32:18 +1030159extern bool initcall_debug;
Arjan van de Venf2511772009-12-13 20:29:01 +0100160
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161#endif
162
163#ifndef MODULE
164
165#ifndef __ASSEMBLY__
166
167/* initcalls are now grouped by functionality into separate
168 * subsections. Ordering inside the subsections is determined
169 * by link order.
170 * For backwards compatibility, initcall() puts the call in
171 * the device init subsection.
Andrew Morton735a7ff2006-10-27 11:42:37 -0700172 *
173 * The `id' arg to __define_initcall() is needed so that multiple initcalls
174 * can point at the same handler without causing duplicate-symbol build errors.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 */
176
Matthew Leach7929d402012-12-17 15:59:32 -0800177#define __define_initcall(fn, id) \
Adrian Bunk3ff6eec2008-01-24 22:16:20 +0100178 static initcall_t __initcall_##fn##id __used \
Matthew Leach7929d402012-12-17 15:59:32 -0800179 __attribute__((__section__(".initcall" #id ".init"))) = fn
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180
Linus Torvaldsb3438f82006-11-20 11:47:18 -0800181/*
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700182 * Early initcalls run before initializing SMP.
183 *
184 * Only for built-in code, not modules.
185 */
Matthew Leach7929d402012-12-17 15:59:32 -0800186#define early_initcall(fn) __define_initcall(fn, early)
Eduard - Gabriel Munteanuc2147a52008-07-25 19:45:11 -0700187
188/*
Linus Torvaldsb3438f82006-11-20 11:47:18 -0800189 * A "pure" initcall has no dependencies on anything else, and purely
190 * initializes variables that couldn't be statically initialized.
191 *
192 * This only exists for built-in code, not for modules.
Jim Cromie96263d22012-06-14 16:00:59 -0600193 * Keep main.c:initcall_level_names[] in sync.
Linus Torvaldsb3438f82006-11-20 11:47:18 -0800194 */
Matthew Leach7929d402012-12-17 15:59:32 -0800195#define pure_initcall(fn) __define_initcall(fn, 0)
Linus Torvaldsb3438f82006-11-20 11:47:18 -0800196
Matthew Leach7929d402012-12-17 15:59:32 -0800197#define core_initcall(fn) __define_initcall(fn, 1)
198#define core_initcall_sync(fn) __define_initcall(fn, 1s)
199#define postcore_initcall(fn) __define_initcall(fn, 2)
200#define postcore_initcall_sync(fn) __define_initcall(fn, 2s)
201#define arch_initcall(fn) __define_initcall(fn, 3)
202#define arch_initcall_sync(fn) __define_initcall(fn, 3s)
203#define subsys_initcall(fn) __define_initcall(fn, 4)
204#define subsys_initcall_sync(fn) __define_initcall(fn, 4s)
205#define fs_initcall(fn) __define_initcall(fn, 5)
206#define fs_initcall_sync(fn) __define_initcall(fn, 5s)
207#define rootfs_initcall(fn) __define_initcall(fn, rootfs)
208#define device_initcall(fn) __define_initcall(fn, 6)
209#define device_initcall_sync(fn) __define_initcall(fn, 6s)
210#define late_initcall(fn) __define_initcall(fn, 7)
211#define late_initcall_sync(fn) __define_initcall(fn, 7s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
213#define __initcall(fn) device_initcall(fn)
214
215#define __exitcall(fn) \
216 static exitcall_t __exitcall_##fn __exit_call = fn
217
218#define console_initcall(fn) \
219 static initcall_t __initcall_##fn \
Adrian Bunk3ff6eec2008-01-24 22:16:20 +0100220 __used __section(.con_initcall.init) = fn
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221
222#define security_initcall(fn) \
223 static initcall_t __initcall_##fn \
Adrian Bunk3ff6eec2008-01-24 22:16:20 +0100224 __used __section(.security_initcall.init) = fn
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225
226struct obs_kernel_param {
227 const char *str;
228 int (*setup_func)(char *);
229 int early;
230};
231
232/*
233 * Only for really core code. See moduleparam.h for the normal way.
234 *
235 * Force the alignment so the compiler doesn't space elements of the
236 * obs_kernel_param "array" too far apart in .init.setup.
237 */
238#define __setup_param(str, unique_id, fn, early) \
Jan Beulichfd6c3a82009-03-12 10:58:33 +0000239 static const char __setup_str_##unique_id[] __initconst \
240 __aligned(1) = str; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 static struct obs_kernel_param __setup_##unique_id \
Adrian Bunk3ff6eec2008-01-24 22:16:20 +0100242 __used __section(.init.setup) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 __attribute__((aligned((sizeof(long))))) \
244 = { __setup_str_##unique_id, fn, early }
245
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246#define __setup(str, fn) \
247 __setup_param(str, fn, fn, 0)
248
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249/* 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)
253
Alon Bar-Lev30d7e0d2007-02-12 00:53:52 -0800254/* Relies on boot_command_line being set */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255void __init parse_early_param(void);
Magnus Damm13977092009-03-30 14:37:25 -0700256void __init parse_early_options(char *cmdline);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257#endif /* __ASSEMBLY__ */
258
259/**
260 * module_init() - driver initialization entry point
261 * @x: function to be run at kernel boot time or module insertion
262 *
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800263 * module_init() will either be called during do_initcalls() (if
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 * builtin) or at module insertion time (if a module). There can only
265 * be one per module.
266 */
267#define module_init(x) __initcall(x);
268
269/**
270 * module_exit() - driver exit entry point
271 * @x: function to be run when driver is removed
272 *
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.
278 */
279#define module_exit(x) __exitcall(x);
280
281#else /* MODULE */
282
Jim Cromie96263d22012-06-14 16:00:59 -0600283/* Don't use these in loadable modules, but some people do... */
Borislav Petkov329bd412009-10-02 15:23:21 +0200284#define early_initcall(fn) module_init(fn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285#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)
292
293#define security_initcall(fn) module_init(fn)
294
Robert P. J. Day4500d062008-07-25 01:45:49 -0700295/* Each module must use one module_init(). */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296#define module_init(initfn) \
297 static inline initcall_t __inittest(void) \
298 { return initfn; } \
299 int init_module(void) __attribute__((alias(#initfn)));
300
301/* This is only required if you want to be unloadable. */
302#define module_exit(exitfn) \
303 static inline exitcall_t __exittest(void) \
304 { return exitfn; } \
305 void cleanup_module(void) __attribute__((alias(#exitfn)));
306
307#define __setup_param(str, unique_id, fn) /* nothing */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308#define __setup(str, func) /* nothing */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309#endif
310
Johannes Bergab3bfca2007-05-06 14:50:49 -0700311/* Data marked not to be saved by software suspend */
Denys Vlasenko07b3bb12010-02-20 01:03:52 +0100312#define __nosavedata __section(.data..nosave)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313
314/* This means "can be init if no module support, otherwise module load
315 may call it." */
316#ifdef CONFIG_MODULES
317#define __init_or_module
318#define __initdata_or_module
Jan Beulich8b5a10f2009-08-19 08:40:48 +0100319#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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323#else
324#define __init_or_module __init
325#define __initdata_or_module __initdata
Jan Beulich8b5a10f2009-08-19 08:40:48 +0100326#define __initconst_or_module __initconst
327#define __INIT_OR_MODULE __INIT
328#define __INITDATA_OR_MODULE __INITDATA
329#define __INITRODATA_OR_MODULE __INITRODATA
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330#endif /*CONFIG_MODULES*/
331
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332#ifdef MODULE
333#define __exit_p(x) x
334#else
335#define __exit_p(x) NULL
336#endif
337
338#endif /* _LINUX_INIT_H */