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-rw-r--r--kernel/include/linux/init.h389
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diff --git a/kernel/include/linux/init.h b/kernel/include/linux/init.h
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+++ b/kernel/include/linux/init.h
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+#ifndef _LINUX_INIT_H
+#define _LINUX_INIT_H
+
+#include <linux/compiler.h>
+#include <linux/types.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 or __initconst 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.
+ */
+
+/* These are for everybody (although not all archs will actually
+ discard it in modules) */
+#define __init __section(.init.text) __cold notrace
+#define __initdata __section(.init.data)
+#define __initconst __constsection(.init.rodata)
+#define __exitdata __section(.exit.data)
+#define __exit_call __used __section(.exitcall.exit)
+
+/*
+ * Some architecture have tool chains which do not handle rodata attributes
+ * correctly. For those disable special sections for const, so that other
+ * architectures can annotate correctly.
+ */
+#ifdef CONFIG_BROKEN_RODATA
+#define __constsection(x)
+#else
+#define __constsection(x) __section(x)
+#endif
+
+/*
+ * modpost check for section mismatches during the kernel build.
+ * A section mismatch happens when there are references from a
+ * code or data section to an init section (both code or data).
+ * The init sections are (for most archs) discarded by the kernel
+ * when early init has completed so all such references are potential bugs.
+ * For exit sections the same issue exists.
+ *
+ * The following markers are used for the cases where the reference to
+ * the *init / *exit section (code or data) is valid and will teach
+ * modpost not to issue a warning. Intended semantics is that a code or
+ * data tagged __ref* can reference code or data from init section without
+ * producing a warning (of course, no warning does not mean code is
+ * correct, so optimally document why the __ref is needed and why it's OK).
+ *
+ * The markers follow same syntax rules as __init / __initdata.
+ */
+#define __ref __section(.ref.text) noinline
+#define __refdata __section(.ref.data)
+#define __refconst __constsection(.ref.rodata)
+
+/* compatibility defines */
+#define __init_refok __ref
+#define __initdata_refok __refdata
+#define __exit_refok __ref
+
+
+#ifdef MODULE
+#define __exitused
+#else
+#define __exitused __used
+#endif
+
+#define __exit __section(.exit.text) __exitused __cold notrace
+
+/* temporary, until all users are removed */
+#define __cpuinit
+#define __cpuinitdata
+#define __cpuinitconst
+#define __cpuexit
+#define __cpuexitdata
+#define __cpuexitconst
+
+/* Used for MEMORY_HOTPLUG */
+#define __meminit __section(.meminit.text) __cold notrace
+#define __meminitdata __section(.meminit.data)
+#define __meminitconst __constsection(.meminit.rodata)
+#define __memexit __section(.memexit.text) __exitused __cold notrace
+#define __memexitdata __section(.memexit.data)
+#define __memexitconst __constsection(.memexit.rodata)
+
+/* For assembly routines */
+#define __HEAD .section ".head.text","ax"
+#define __INIT .section ".init.text","ax"
+#define __FINIT .previous
+
+#define __INITDATA .section ".init.data","aw",%progbits
+#define __INITRODATA .section ".init.rodata","a",%progbits
+#define __FINITDATA .previous
+
+/* temporary, until all users are removed */
+#define __CPUINIT
+
+#define __MEMINIT .section ".meminit.text", "ax"
+#define __MEMINITDATA .section ".meminit.data", "aw"
+#define __MEMINITRODATA .section ".meminit.rodata", "a"
+
+/* silence warnings when references are OK */
+#define __REF .section ".ref.text", "ax"
+#define __REFDATA .section ".ref.data", "aw"
+#define __REFCONST .section ".ref.rodata", "a"
+
+#ifndef __ASSEMBLY__
+/*
+ * Used for initialization calls..
+ */
+typedef int (*initcall_t)(void);
+typedef void (*exitcall_t)(void);
+
+extern initcall_t __con_initcall_start[], __con_initcall_end[];
+extern initcall_t __security_initcall_start[], __security_initcall_end[];
+
+/* Used for contructor calls. */
+typedef void (*ctor_fn_t)(void);
+
+/* Defined in init/main.c */
+extern int do_one_initcall(initcall_t fn);
+extern char __initdata boot_command_line[];
+extern char *saved_command_line;
+extern unsigned int reset_devices;
+
+/* used by init/main.c */
+void setup_arch(char **);
+void prepare_namespace(void);
+void __init load_default_modules(void);
+int __init init_rootfs(void);
+
+extern void (*late_time_init)(void);
+
+extern bool initcall_debug;
+
+#endif
+
+#ifndef MODULE
+
+#ifndef __ASSEMBLY__
+
+#ifdef CONFIG_LTO
+/* Work around a LTO gcc problem: when there is no reference to a variable
+ * in a module it will be moved to the end of the program. This causes
+ * reordering of initcalls which the kernel does not like.
+ * Add a dummy reference function to avoid this. The function is
+ * deleted by the linker.
+ */
+#define LTO_REFERENCE_INITCALL(x) \
+ ; /* yes this is needed */ \
+ static __used __exit void *reference_##x(void) \
+ { \
+ return &x; \
+ }
+#else
+#define LTO_REFERENCE_INITCALL(x)
+#endif
+
+/* initcalls are now grouped by functionality into separate
+ * subsections. Ordering inside the subsections is determined
+ * by link order.
+ * For backwards compatibility, initcall() puts the call in
+ * the device init subsection.
+ *
+ * The `id' arg to __define_initcall() is needed so that multiple initcalls
+ * can point at the same handler without causing duplicate-symbol build errors.
+ */
+
+#define __define_initcall(fn, id) \
+ static initcall_t __initcall_##fn##id __used \
+ __attribute__((__section__(".initcall" #id ".init"))) = fn; \
+ LTO_REFERENCE_INITCALL(__initcall_##fn##id)
+
+/*
+ * Early initcalls run before initializing SMP.
+ *
+ * Only for built-in code, not modules.
+ */
+#define early_initcall(fn) __define_initcall(fn, early)
+
+/*
+ * A "pure" initcall has no dependencies on anything else, and purely
+ * initializes variables that couldn't be statically initialized.
+ *
+ * This only exists for built-in code, not for modules.
+ * Keep main.c:initcall_level_names[] in sync.
+ */
+#define pure_initcall(fn) __define_initcall(fn, 0)
+
+#define core_initcall(fn) __define_initcall(fn, 1)
+#define core_initcall_sync(fn) __define_initcall(fn, 1s)
+#define postcore_initcall(fn) __define_initcall(fn, 2)
+#define postcore_initcall_sync(fn) __define_initcall(fn, 2s)
+#define arch_initcall(fn) __define_initcall(fn, 3)
+#define arch_initcall_sync(fn) __define_initcall(fn, 3s)
+#define subsys_initcall(fn) __define_initcall(fn, 4)
+#define subsys_initcall_sync(fn) __define_initcall(fn, 4s)
+#define fs_initcall(fn) __define_initcall(fn, 5)
+#define fs_initcall_sync(fn) __define_initcall(fn, 5s)
+#define rootfs_initcall(fn) __define_initcall(fn, rootfs)
+#define device_initcall(fn) __define_initcall(fn, 6)
+#define device_initcall_sync(fn) __define_initcall(fn, 6s)
+#define late_initcall(fn) __define_initcall(fn, 7)
+#define late_initcall_sync(fn) __define_initcall(fn, 7s)
+
+#define __initcall(fn) device_initcall(fn)
+
+#define __exitcall(fn) \
+ static exitcall_t __exitcall_##fn __exit_call = fn
+
+#define console_initcall(fn) \
+ static initcall_t __initcall_##fn \
+ __used __section(.con_initcall.init) = fn
+
+#define security_initcall(fn) \
+ static initcall_t __initcall_##fn \
+ __used __section(.security_initcall.init) = fn
+
+struct obs_kernel_param {
+ const char *str;
+ int (*setup_func)(char *);
+ int early;
+};
+
+/*
+ * Only for really core code. See moduleparam.h for the normal way.
+ *
+ * Force the alignment so the compiler doesn't space elements of the
+ * obs_kernel_param "array" too far apart in .init.setup.
+ */
+#define __setup_param(str, unique_id, fn, early) \
+ static const char __setup_str_##unique_id[] __initconst \
+ __aligned(1) = str; \
+ static struct obs_kernel_param __setup_##unique_id \
+ __used __section(.init.setup) \
+ __attribute__((aligned((sizeof(long))))) \
+ = { __setup_str_##unique_id, fn, early }
+
+#define __setup(str, fn) \
+ __setup_param(str, fn, fn, 0)
+
+/*
+ * NOTE: fn is as per module_param, not __setup!
+ * Emits warning if fn returns non-zero.
+ */
+#define early_param(str, fn) \
+ __setup_param(str, fn, fn, 1)
+
+#define early_param_on_off(str_on, str_off, var, config) \
+ \
+ int var = IS_ENABLED(config); \
+ \
+ static int __init parse_##var##_on(char *arg) \
+ { \
+ var = 1; \
+ return 0; \
+ } \
+ __setup_param(str_on, parse_##var##_on, parse_##var##_on, 1); \
+ \
+ static int __init parse_##var##_off(char *arg) \
+ { \
+ var = 0; \
+ return 0; \
+ } \
+ __setup_param(str_off, parse_##var##_off, parse_##var##_off, 1)
+
+/* Relies on boot_command_line being set */
+void __init parse_early_param(void);
+void __init parse_early_options(char *cmdline);
+#endif /* __ASSEMBLY__ */
+
+/**
+ * module_init() - driver initialization entry point
+ * @x: function to be run at kernel boot time or module insertion
+ *
+ * module_init() will either be called during do_initcalls() (if
+ * builtin) or at module insertion time (if a module). There can only
+ * be one per module.
+ */
+#define module_init(x) __initcall(x);
+
+/**
+ * module_exit() - driver exit entry point
+ * @x: function to be run when driver is removed
+ *
+ * module_exit() will wrap the driver clean-up code
+ * with cleanup_module() when used with rmmod when
+ * the driver is a module. If the driver is statically
+ * compiled into the kernel, module_exit() has no effect.
+ * There can only be one per module.
+ */
+#define module_exit(x) __exitcall(x);
+
+#else /* MODULE */
+
+/*
+ * In most cases loadable modules do not need custom
+ * initcall levels. There are still some valid cases where
+ * a driver may be needed early if built in, and does not
+ * matter when built as a loadable module. Like bus
+ * snooping debug drivers.
+ */
+#define early_initcall(fn) module_init(fn)
+#define core_initcall(fn) module_init(fn)
+#define core_initcall_sync(fn) module_init(fn)
+#define postcore_initcall(fn) module_init(fn)
+#define postcore_initcall_sync(fn) module_init(fn)
+#define arch_initcall(fn) module_init(fn)
+#define subsys_initcall(fn) module_init(fn)
+#define subsys_initcall_sync(fn) module_init(fn)
+#define fs_initcall(fn) module_init(fn)
+#define fs_initcall_sync(fn) module_init(fn)
+#define rootfs_initcall(fn) module_init(fn)
+#define device_initcall(fn) module_init(fn)
+#define device_initcall_sync(fn) module_init(fn)
+#define late_initcall(fn) module_init(fn)
+#define late_initcall_sync(fn) module_init(fn)
+
+#define console_initcall(fn) module_init(fn)
+#define security_initcall(fn) module_init(fn)
+
+/* Each module must use one module_init(). */
+#define module_init(initfn) \
+ static inline initcall_t __inittest(void) \
+ { return initfn; } \
+ int init_module(void) __attribute__((alias(#initfn)));
+
+/* This is only required if you want to be unloadable. */
+#define module_exit(exitfn) \
+ static inline exitcall_t __exittest(void) \
+ { return exitfn; } \
+ void cleanup_module(void) __attribute__((alias(#exitfn)));
+
+#define __setup_param(str, unique_id, fn) /* nothing */
+#define __setup(str, func) /* nothing */
+#endif
+
+/* Data marked not to be saved by software suspend */
+#define __nosavedata __section(.data..nosave)
+
+/* This means "can be init if no module support, otherwise module load
+ may call it." */
+#ifdef CONFIG_MODULES
+#define __init_or_module
+#define __initdata_or_module
+#define __initconst_or_module
+#define __INIT_OR_MODULE .text
+#define __INITDATA_OR_MODULE .data
+#define __INITRODATA_OR_MODULE .section ".rodata","a",%progbits
+#else
+#define __init_or_module __init
+#define __initdata_or_module __initdata
+#define __initconst_or_module __initconst
+#define __INIT_OR_MODULE __INIT
+#define __INITDATA_OR_MODULE __INITDATA
+#define __INITRODATA_OR_MODULE __INITRODATA
+#endif /*CONFIG_MODULES*/
+
+#ifdef MODULE
+#define __exit_p(x) x
+#else
+#define __exit_p(x) NULL
+#endif
+
+#endif /* _LINUX_INIT_H */