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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_UML_INIT_H
3#define _LINUX_UML_INIT_H
4
5/* These macros are used to mark some functions or
6 * initialized data (doesn't apply to uninitialized data)
7 * as `initialization' functions. The kernel can take this
8 * as hint that the function is used only during the initialization
9 * phase and free up used memory resources after
10 *
11 * Usage:
12 * For functions:
13 *
14 * You should add __init immediately before the function name, like:
15 *
16 * static void __init initme(int x, int y)
17 * {
18 * extern int z; z = x * y;
19 * }
20 *
21 * If the function has a prototype somewhere, you can also add
22 * __init between closing brace of the prototype and semicolon:
23 *
24 * extern int initialize_foobar_device(int, int, int) __init;
25 *
26 * For initialized data:
27 * You should insert __initdata between the variable name and equal
28 * sign followed by value, e.g.:
29 *
30 * static int init_variable __initdata = 0;
31 * static const char linux_logo[] __initconst = { 0x32, 0x36, ... };
32 *
33 * Don't forget to initialize data not at file scope, i.e. within a function,
34 * as gcc otherwise puts the data into the bss section and not into the init
35 * section.
36 *
37 * Also note, that this data cannot be "const".
38 */
39
40#ifndef _LINUX_INIT_H
41typedef int (*initcall_t)(void);
42typedef void (*exitcall_t)(void);
43
44#include <linux/compiler_types.h>
45
46/* These are for everybody (although not all archs will actually
47 discard it in modules) */
48#define __init __section(".init.text")
49#define __initdata __section(".init.data")
50#define __exitdata __section(".exit.data")
51#define __exit_call __used __section(".exitcall.exit")
52
53#ifdef MODULE
54#define __exit __section(".exit.text")
55#else
56#define __exit __used __section(".exit.text")
57#endif
58
59#endif
60
61#ifndef MODULE
62struct uml_param {
63 const char *str;
64 int (*setup_func)(char *, int *);
65};
66
67extern initcall_t __uml_postsetup_start, __uml_postsetup_end;
68extern const char *__uml_help_start, *__uml_help_end;
69#endif
70
71#define __uml_exitcall(fn) \
72 static exitcall_t __uml_exitcall_##fn __uml_exit_call = fn
73
74extern struct uml_param __uml_setup_start, __uml_setup_end;
75
76#define __uml_postsetup(fn) \
77 static initcall_t __uml_postsetup_##fn __uml_postsetup_call = fn
78
79#define __non_empty_string(dummyname,string) \
80 struct __uml_non_empty_string_struct_##dummyname \
81 { \
82 char _string[sizeof(string)-2]; \
83 }
84
85#ifndef MODULE
86#define __uml_setup(str, fn, help...) \
87 __non_empty_string(fn ##_setup, str); \
88 __uml_help(fn, help); \
89 static char __uml_setup_str_##fn[] __initdata = str; \
90 static struct uml_param __uml_setup_##fn __uml_init_setup = { __uml_setup_str_##fn, fn }
91#else
92#define __uml_setup(str, fn, help...) \
93
94#endif
95
96#define __uml_help(fn, help...) \
97 __non_empty_string(fn ##__help, help); \
98 static char __uml_help_str_##fn[] __initdata = help; \
99 static const char *__uml_help_##fn __uml_setup_help = __uml_help_str_##fn
100
101/*
102 * Mark functions and data as being only used at initialization
103 * or exit time.
104 */
105#define __uml_init_setup __used __section(".uml.setup.init")
106#define __uml_setup_help __used __section(".uml.help.init")
107#define __uml_postsetup_call __used __section(".uml.postsetup.init")
108#define __uml_exit_call __used __section(".uml.exitcall.exit")
109
110#ifdef __UM_HOST__
111
112#define __define_initcall(level,fn) \
113 static initcall_t __initcall_##fn __used \
114 __attribute__((__section__(".initcall" level ".init"))) = fn
115
116/* Userspace initcalls shouldn't depend on anything in the kernel, so we'll
117 * make them run first.
118 */
119#define __initcall(fn) __define_initcall("1", fn)
120
121#define __exitcall(fn) static exitcall_t __exitcall_##fn __exit_call = fn
122
123#define __init_call __used __section(".initcall.init")
124
125#endif
126
127#endif /* _LINUX_UML_INIT_H */