Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 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 char linux_logo[] __initdata = { 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 | /* These are for everybody (although not all archs will actually |
| 44 | discard it in modules) */ |
| 45 | #define __init __attribute__ ((__section__ (".init.text"))) |
| 46 | #define __initdata __attribute__ ((__section__ (".init.data"))) |
| 47 | #define __exitdata __attribute__ ((__section__(".exit.data"))) |
| 48 | #define __exit_call __attribute_used__ __attribute__ ((__section__ (".exitcall.exit"))) |
| 49 | |
| 50 | #ifdef MODULE |
| 51 | #define __exit __attribute__ ((__section__(".exit.text"))) |
| 52 | #else |
| 53 | #define __exit __attribute_used__ __attribute__ ((__section__(".exit.text"))) |
| 54 | #endif |
| 55 | |
| 56 | #endif |
| 57 | |
| 58 | #ifndef MODULE |
| 59 | struct uml_param { |
| 60 | const char *str; |
| 61 | int (*setup_func)(char *, int *); |
| 62 | }; |
| 63 | |
| 64 | extern initcall_t __uml_initcall_start, __uml_initcall_end; |
| 65 | extern initcall_t __uml_postsetup_start, __uml_postsetup_end; |
| 66 | extern const char *__uml_help_start, *__uml_help_end; |
| 67 | #endif |
| 68 | |
| 69 | #define __uml_initcall(fn) \ |
| 70 | static initcall_t __uml_initcall_##fn __uml_init_call = fn |
| 71 | |
| 72 | #define __uml_exitcall(fn) \ |
| 73 | static exitcall_t __uml_exitcall_##fn __uml_exit_call = fn |
| 74 | |
| 75 | extern struct uml_param __uml_setup_start, __uml_setup_end; |
| 76 | |
| 77 | #define __uml_postsetup(fn) \ |
| 78 | static initcall_t __uml_postsetup_##fn __uml_postsetup_call = fn |
| 79 | |
| 80 | #define __non_empty_string(dummyname,string) \ |
| 81 | struct __uml_non_empty_string_struct_##dummyname \ |
| 82 | { \ |
| 83 | char _string[sizeof(string)-2]; \ |
| 84 | } |
| 85 | |
| 86 | #ifndef MODULE |
| 87 | #define __uml_setup(str, fn, help...) \ |
| 88 | __non_empty_string(fn ##_setup, str); \ |
| 89 | __uml_help(fn, help); \ |
| 90 | static char __uml_setup_str_##fn[] __initdata = str; \ |
| 91 | static struct uml_param __uml_setup_##fn __uml_init_setup = { __uml_setup_str_##fn, fn } |
| 92 | #else |
| 93 | #define __uml_setup(str, fn, help...) \ |
| 94 | |
| 95 | #endif |
| 96 | |
| 97 | #define __uml_help(fn, help...) \ |
| 98 | __non_empty_string(fn ##__help, help); \ |
| 99 | static char __uml_help_str_##fn[] __initdata = help; \ |
| 100 | static const char *__uml_help_##fn __uml_setup_help = __uml_help_str_##fn |
| 101 | |
| 102 | /* |
| 103 | * Mark functions and data as being only used at initialization |
| 104 | * or exit time. |
| 105 | */ |
| 106 | #define __uml_init_setup __attribute_used__ __attribute__ ((__section__ (".uml.setup.init"))) |
| 107 | #define __uml_setup_help __attribute_used__ __attribute__ ((__section__ (".uml.help.init"))) |
| 108 | #define __uml_init_call __attribute_used__ __attribute__ ((__section__ (".uml.initcall.init"))) |
| 109 | #define __uml_postsetup_call __attribute_used__ __attribute__ ((__section__ (".uml.postsetup.init"))) |
| 110 | #define __uml_exit_call __attribute_used__ __attribute__ ((__section__ (".uml.exitcall.exit"))) |
| 111 | |
| 112 | #ifndef __KERNEL__ |
| 113 | |
| 114 | #define __initcall(fn) static initcall_t __initcall_##fn __init_call = fn |
| 115 | #define __exitcall(fn) static exitcall_t __exitcall_##fn __exit_call = fn |
| 116 | |
| 117 | #define __init_call __attribute__ ((unused,__section__ (".initcall.init"))) |
| 118 | |
| 119 | #endif |
| 120 | |
| 121 | #endif /* _LINUX_UML_INIT_H */ |
| 122 | |
| 123 | /* |
| 124 | * Overrides for Emacs so that we follow Linus's tabbing style. |
| 125 | * Emacs will notice this stuff at the end of the file and automatically |
| 126 | * adjust the settings for this buffer only. This must remain at the end |
| 127 | * of the file. |
| 128 | * --------------------------------------------------------------------------- |
| 129 | * Local variables: |
| 130 | * c-file-style: "linux" |
| 131 | * End: |
| 132 | */ |