4 #include <linux/config.h>
5 #include <linux/compiler.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 char linux_logo[] __initdata = { 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 __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")))
50 #define __exit __attribute__ ((__section__(".exit.text")))
52 #define __exit __attribute_used__ __attribute__ ((__section__(".exit.text")))
55 /* For assembly routines */
56 #define __INIT .section ".init.text","ax"
57 #define __FINIT .previous
58 #define __INITDATA .section ".init.data","aw"
62 * Used for initialization calls..
64 typedef int (*initcall_t)(void);
65 typedef void (*exitcall_t)(void);
67 extern initcall_t __con_initcall_start, __con_initcall_end;
68 extern initcall_t __security_initcall_start, __security_initcall_end;
75 /* initcalls are now grouped by functionality into separate
76 * subsections. Ordering inside the subsections is determined
78 * For backwards compatibility, initcall() puts the call in
79 * the device init subsection.
82 #define __define_initcall(level,fn) \
83 static initcall_t __initcall_##fn __attribute_used__ \
84 __attribute__((__section__(".initcall" level ".init"))) = fn
86 #define core_initcall(fn) __define_initcall("1",fn)
87 #define postcore_initcall(fn) __define_initcall("2",fn)
88 #define arch_initcall(fn) __define_initcall("3",fn)
89 #define subsys_initcall(fn) __define_initcall("4",fn)
90 #define fs_initcall(fn) __define_initcall("5",fn)
91 #define device_initcall(fn) __define_initcall("6",fn)
92 #define late_initcall(fn) __define_initcall("7",fn)
94 #define __initcall(fn) device_initcall(fn)
96 #define __exitcall(fn) \
97 static exitcall_t __exitcall_##fn __exit_call = fn
99 #define console_initcall(fn) \
100 static initcall_t __initcall_##fn \
101 __attribute_used__ __attribute__((__section__(".con_initcall.init")))=fn
103 #define security_initcall(fn) \
104 static initcall_t __initcall_##fn \
105 __attribute_used__ __attribute__((__section__(".security_initcall.init"))) = fn
107 struct obs_kernel_param {
109 int (*setup_func)(char *);
112 /* OBSOLETE: see moduleparam.h for the right way. */
113 #define __setup_param(str, unique_id, fn) \
114 static char __setup_str_##unique_id[] __initdata = str; \
115 static struct obs_kernel_param __setup_##unique_id \
117 __attribute__((__section__(".init.setup"))) \
118 = { __setup_str_##unique_id, fn }
120 #define __setup_null_param(str, unique_id) \
121 __setup_param(str, unique_id, NULL)
123 #define __setup(str, fn) \
124 __setup_param(str, fn, fn)
126 #define __obsolete_setup(str) \
127 __setup_null_param(str, __LINE__)
129 #endif /* __ASSEMBLY__ */
132 * module_init() - driver initialization entry point
133 * @x: function to be run at kernel boot time or module insertion
135 * module_init() will either be called during do_initcalls (if
136 * builtin) or at module insertion time (if a module). There can only
139 #define module_init(x) __initcall(x);
142 * module_exit() - driver exit entry point
143 * @x: function to be run when driver is removed
145 * module_exit() will wrap the driver clean-up code
146 * with cleanup_module() when used with rmmod when
147 * the driver is a module. If the driver is statically
148 * compiled into the kernel, module_exit() has no effect.
149 * There can only be one per module.
151 #define module_exit(x) __exitcall(x);
155 /* Don't use these in modules, but some people do... */
156 #define core_initcall(fn) module_init(fn)
157 #define postcore_initcall(fn) module_init(fn)
158 #define arch_initcall(fn) module_init(fn)
159 #define subsys_initcall(fn) module_init(fn)
160 #define fs_initcall(fn) module_init(fn)
161 #define device_initcall(fn) module_init(fn)
162 #define late_initcall(fn) module_init(fn)
164 #define security_initcall(fn) module_init(fn)
166 /* These macros create a dummy inline: gcc 2.9x does not count alias
167 as usage, hence the `unused function' warning when __init functions
168 are declared static. We use the dummy __*_module_inline functions
169 both to kill the warning and check the type of the init/cleanup
172 /* Each module must use one module_init(), or one no_module_init */
173 #define module_init(initfn) \
174 static inline initcall_t __inittest(void) \
176 int init_module(void) __attribute__((alias(#initfn)));
178 /* This is only required if you want to be unloadable. */
179 #define module_exit(exitfn) \
180 static inline exitcall_t __exittest(void) \
182 void cleanup_module(void) __attribute__((alias(#exitfn)));
184 #define __setup_param(str, unique_id, fn) /* nothing */
185 #define __setup_null_param(str, unique_id) /* nothing */
186 #define __setup(str, func) /* nothing */
187 #define __obsolete_setup(str) /* nothing */
190 /* Data marked not to be saved by software_suspend() */
191 #define __nosavedata __attribute__ ((__section__ (".data.nosave")))
193 /* This means "can be init if no module support, otherwise module load
195 #ifdef CONFIG_MODULES
196 #define __init_or_module
197 #define __initdata_or_module
199 #define __init_or_module __init
200 #define __initdata_or_module __initdata
201 #endif /*CONFIG_MODULES*/
203 #ifdef CONFIG_HOTPLUG
205 #define __devinitdata
207 #define __devexitdata
209 #define __devinit __init
210 #define __devinitdata __initdata
211 #define __devexit __exit
212 #define __devexitdata __exitdata
215 /* Functions marked as __devexit may be discarded at kernel link time, depending
216 on config options. Newer versions of binutils detect references from
217 retained sections to discarded sections and flag an error. Pointers to
218 __devexit functions must use __devexit_p(function_name), the wrapper will
219 insert either the function_name or NULL, depending on the config options.
221 #if defined(MODULE) || defined(CONFIG_HOTPLUG)
222 #define __devexit_p(x) x
224 #define __devexit_p(x) NULL
228 #define __exit_p(x) x
230 #define __exit_p(x) NULL
233 #endif /* _LINUX_INIT_H */