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Diffstat (limited to 'arch/um/include/shared/init.h')
-rw-r--r-- | arch/um/include/shared/init.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/um/include/shared/init.h b/arch/um/include/shared/init.h new file mode 100644 index 000000000..1a659e2e8 --- /dev/null +++ b/arch/um/include/shared/init.h @@ -0,0 +1,127 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_UML_INIT_H +#define _LINUX_UML_INIT_H + +/* These macros are used to mark some functions or + * initialized data (doesn't apply to uninitialized data) + * as `initialization' functions. The kernel can take this + * as hint that the function is used only during the initialization + * phase and free up used memory resources after + * + * Usage: + * For functions: + * + * You should add __init immediately before the function name, like: + * + * static void __init initme(int x, int y) + * { + * extern int z; z = x * y; + * } + * + * If the function has a prototype somewhere, you can also add + * __init between closing brace of the prototype and semicolon: + * + * extern int initialize_foobar_device(int, int, int) __init; + * + * For initialized data: + * You should insert __initdata between the variable name and equal + * sign followed by value, e.g.: + * + * static int init_variable __initdata = 0; + * static const char linux_logo[] __initconst = { 0x32, 0x36, ... }; + * + * Don't forget to initialize data not at file scope, i.e. within a function, + * as gcc otherwise puts the data into the bss section and not into the init + * section. + * + * Also note, that this data cannot be "const". + */ + +#ifndef _LINUX_INIT_H +typedef int (*initcall_t)(void); +typedef void (*exitcall_t)(void); + +#include <linux/compiler_types.h> + +/* These are for everybody (although not all archs will actually + discard it in modules) */ +#define __init __section(".init.text") +#define __initdata __section(".init.data") +#define __exitdata __section(".exit.data") +#define __exit_call __used __section(".exitcall.exit") + +#ifdef MODULE +#define __exit __section(".exit.text") +#else +#define __exit __used __section(".exit.text") +#endif + +#endif + +#ifndef MODULE +struct uml_param { + const char *str; + int (*setup_func)(char *, int *); +}; + +extern initcall_t __uml_postsetup_start, __uml_postsetup_end; +extern const char *__uml_help_start, *__uml_help_end; +#endif + +#define __uml_exitcall(fn) \ + static exitcall_t __uml_exitcall_##fn __uml_exit_call = fn + +extern struct uml_param __uml_setup_start, __uml_setup_end; + +#define __uml_postsetup(fn) \ + static initcall_t __uml_postsetup_##fn __uml_postsetup_call = fn + +#define __non_empty_string(dummyname,string) \ + struct __uml_non_empty_string_struct_##dummyname \ + { \ + char _string[sizeof(string)-2]; \ + } + +#ifndef MODULE +#define __uml_setup(str, fn, help...) \ + __non_empty_string(fn ##_setup, str); \ + __uml_help(fn, help); \ + static char __uml_setup_str_##fn[] __initdata = str; \ + static struct uml_param __uml_setup_##fn __uml_init_setup = { __uml_setup_str_##fn, fn } +#else +#define __uml_setup(str, fn, help...) \ + +#endif + +#define __uml_help(fn, help...) \ + __non_empty_string(fn ##__help, help); \ + static char __uml_help_str_##fn[] __initdata = help; \ + static const char *__uml_help_##fn __uml_setup_help = __uml_help_str_##fn + +/* + * Mark functions and data as being only used at initialization + * or exit time. + */ +#define __uml_init_setup __used __section(".uml.setup.init") +#define __uml_setup_help __used __section(".uml.help.init") +#define __uml_postsetup_call __used __section(".uml.postsetup.init") +#define __uml_exit_call __used __section(".uml.exitcall.exit") + +#ifdef __UM_HOST__ + +#define __define_initcall(level,fn) \ + static initcall_t __initcall_##fn __used \ + __attribute__((__section__(".initcall" level ".init"))) = fn + +/* Userspace initcalls shouldn't depend on anything in the kernel, so we'll + * make them run first. + */ +#define __initcall(fn) __define_initcall("1", fn) + +#define __exitcall(fn) static exitcall_t __exitcall_##fn __exit_call = fn + +#define __init_call __used __section(".initcall.init") + +#endif + +#endif /* _LINUX_UML_INIT_H */ |