/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_INIT_H
#define _LINUX_INIT_H
#include <linux/compiler.h>
#include <linux/types.h>
/* Built-in __init functions needn't be compiled with retpoline */
#if defined(__noretpoline) && !defined(MODULE)
#define __noinitretpoline __noretpoline
#else
#define __noinitretpoline
#endif
/* 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 __latent_entropy __noinitretpoline
#define __initdata __section(.init.data)
#define __initconst __section(.init.rodata)
#define __exitdata __section(.exit.data)
#define __exit_call __used __section(.exitcall.exit)
/*
* 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 __section(.ref.rodata)
#ifdef MODULE
#define __exitused
#else
#define __exitused __used
#endif
#define __exit __section(.exit.text) __exitused __cold notrace
/* Used for MEMORY_HOTPLUG */
#define __meminit __section(.meminit.text) __cold notrace \
__latent_entropy
#define __meminitdata __section(.meminit.data)
#define __meminitconst __section(.meminit.rodata)
#define __memexit __section(.memexit.text) __exitused __cold notrace
#define __memexitdata __section(.memexit.data)
#define __memexitconst __section(.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
#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);
#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
typedef int initcall_entry_t;
static inline initcall_t initcall_from_entry(initcall_entry_t *entry)
{
return offset_to_ptr(entry);
}
#else
typedef initcall_t initcall_entry_t;
static inline initcall_t initcall_from_entry(initcall_entry_t *entry)
{
return *entry;
}
#endif
extern initcall_entry_t __con_initcall_start[], __con_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);
int __init init_rootfs(void);
#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_STRICT_MODULE_RWX)
extern bool rodata_enabled;
#endif
#ifdef CONFIG_STRICT_KERNEL_RWX
void mark_rodata_ro(void);
#endif
extern void (*late_time_init)(void);
extern bool initcall_debug;
#endif
#ifndef MODULE
#ifndef __ASSEMBLY__
/*
* 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.
*
* Initcalls are run by placing pointers in initcall sections that the
* kernel iterates at runtime. The linker can do dead code / data elimination
* and remove that completely, so the initcall sections have to be marked
* as KEEP() in the linker script.
*/
#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
#define ___define_initcall(fn, id, __sec) \
__ADDRESSABLE(fn) \
asm(".section \"" #__sec ".init\", \"a\" \n" \
"__initcall_" #fn #id ": \n" \
".long " #fn " - . \n" \
".previous \n");
#else
#define ___define_initcall(fn, id, __sec) \
static initcall_t __initcall_##fn##id __used \
__attribute__((__section__(#__sec ".init"))) = fn;
#endif
#define __define_initcall(fn, id) ___define_initcall(fn, id, .initcall##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) ___define_initcall(fn,, .con_initcall)
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__ */
#else /* MODULE */
#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)
#ifdef MODULE
#define __exit_p(x) x
#else
#define __exit_p(x) NULL
#endif
#endif /* _LINUX_INIT_H */
