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-rw-r--r--arch/um/include/shared/init.h127
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diff --git a/arch/um/include/shared/init.h b/arch/um/include/shared/init.h
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+++ b/arch/um/include/shared/init.h
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+/* 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 */