1 #ifndef _LINUX_UML_INIT_H 2 #define _LINUX_UML_INIT_H 3 4 /* These macros are used to mark some functions or 5 * initialized data (doesn't apply to uninitialized data) 6 * as `initialization' functions. The kernel can take this 7 * as hint that the function is used only during the initialization 8 * phase and free up used memory resources after 9 * 10 * Usage: 11 * For functions: 12 * 13 * You should add __init immediately before the function name, like: 14 * 15 * static void __init initme(int x, int y) 16 * { 17 * extern int z; z = x * y; 18 * } 19 * 20 * If the function has a prototype somewhere, you can also add 21 * __init between closing brace of the prototype and semicolon: 22 * 23 * extern int initialize_foobar_device(int, int, int) __init; 24 * 25 * For initialized data: 26 * You should insert __initdata between the variable name and equal 27 * sign followed by value, e.g.: 28 * 29 * static int init_variable __initdata = 0; 30 * static const char linux_logo[] __initconst = { 0x32, 0x36, ... }; 31 * 32 * Don't forget to initialize data not at file scope, i.e. within a function, 33 * as gcc otherwise puts the data into the bss section and not into the init 34 * section. 35 * 36 * Also note, that this data cannot be "const". 37 */ 38 39 #ifndef _LINUX_INIT_H 40 typedef int (*initcall_t)(void); 41 typedef void (*exitcall_t)(void); 42 43 #ifndef __KERNEL__ 44 #ifndef __section 45 # define __section(S) __attribute__ ((__section__(#S))) 46 #endif 47 48 #if __GNUC__ == 3 49 50 #if __GNUC_MINOR__ >= 3 51 # define __used __attribute__((__used__)) 52 #else 53 # define __used __attribute__((__unused__)) 54 #endif 55 56 #else 57 #if __GNUC__ == 4 58 # define __used __attribute__((__used__)) 59 #endif 60 #endif 61 62 #else 63 #include <linux/compiler.h> 64 #endif 65 /* These are for everybody (although not all archs will actually 66 discard it in modules) */ 67 #define __init __section(.init.text) 68 #define __initdata __section(.init.data) 69 #define __exitdata __section(.exit.data) 70 #define __exit_call __used __section(.exitcall.exit) 71 72 #ifdef MODULE 73 #define __exit __section(.exit.text) 74 #else 75 #define __exit __used __section(.exit.text) 76 #endif 77 78 #endif 79 80 #ifndef MODULE 81 struct uml_param { 82 const char *str; 83 int (*setup_func)(char *, int *); 84 }; 85 86 extern initcall_t __uml_initcall_start, __uml_initcall_end; 87 extern initcall_t __uml_postsetup_start, __uml_postsetup_end; 88 extern const char *__uml_help_start, *__uml_help_end; 89 #endif 90 91 #define __uml_initcall(fn) \ 92 static initcall_t __uml_initcall_##fn __uml_init_call = fn 93 94 #define __uml_exitcall(fn) \ 95 static exitcall_t __uml_exitcall_##fn __uml_exit_call = fn 96 97 extern struct uml_param __uml_setup_start, __uml_setup_end; 98 99 #define __uml_postsetup(fn) \ 100 static initcall_t __uml_postsetup_##fn __uml_postsetup_call = fn 101 102 #define __non_empty_string(dummyname,string) \ 103 struct __uml_non_empty_string_struct_##dummyname \ 104 { \ 105 char _string[sizeof(string)-2]; \ 106 } 107 108 #ifndef MODULE 109 #define __uml_setup(str, fn, help...) \ 110 __non_empty_string(fn ##_setup, str); \ 111 __uml_help(fn, help); \ 112 static char __uml_setup_str_##fn[] __initdata = str; \ 113 static struct uml_param __uml_setup_##fn __uml_init_setup = { __uml_setup_str_##fn, fn } 114 #else 115 #define __uml_setup(str, fn, help...) \ 116 117 #endif 118 119 #define __uml_help(fn, help...) \ 120 __non_empty_string(fn ##__help, help); \ 121 static char __uml_help_str_##fn[] __initdata = help; \ 122 static const char *__uml_help_##fn __uml_setup_help = __uml_help_str_##fn 123 124 /* 125 * Mark functions and data as being only used at initialization 126 * or exit time. 127 */ 128 #define __uml_init_setup __used __section(.uml.setup.init) 129 #define __uml_setup_help __used __section(.uml.help.init) 130 #define __uml_init_call __used __section(.uml.initcall.init) 131 #define __uml_postsetup_call __used __section(.uml.postsetup.init) 132 #define __uml_exit_call __used __section(.uml.exitcall.exit) 133 134 #ifndef __KERNEL__ 135 136 #define __define_initcall(level,fn) \ 137 static initcall_t __initcall_##fn __used \ 138 __attribute__((__section__(".initcall" level ".init"))) = fn 139 140 /* Userspace initcalls shouldn't depend on anything in the kernel, so we'll 141 * make them run first. 142 */ 143 #define __initcall(fn) __define_initcall("1", fn) 144 145 #define __exitcall(fn) static exitcall_t __exitcall_##fn __exit_call = fn 146 147 #define __init_call __used __section(.initcall.init) 148 149 #endif 150 151 #endif /* _LINUX_UML_INIT_H */ 152