linux/include/linux/thread_info.h

/* SPDX-License-Identifier: GPL-2.0 */
/* thread_info.h: common low-level thread information accessors
 *
 * Copyright (C) 2002  David Howells ([email protected])
 * - Incorporating suggestions made by Linus Torvalds
 */

#ifndef _LINUX_THREAD_INFO_H
#define _LINUX_THREAD_INFO_H

#include <linux/types.h>
#include <linux/limits.h>
#include <linux/bug.h>
#include <linux/restart_block.h>
#include <linux/errno.h>

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() …
#endif

#include <linux/bitops.h>

/*
 * For per-arch arch_within_stack_frames() implementations, defined in
 * asm/thread_info.h.
 */
enum { … };

#ifdef CONFIG_GENERIC_ENTRY
enum syscall_work_bit { … };

#define SYSCALL_WORK_SECCOMP …
#define SYSCALL_WORK_SYSCALL_TRACEPOINT …
#define SYSCALL_WORK_SYSCALL_TRACE …
#define SYSCALL_WORK_SYSCALL_EMU …
#define SYSCALL_WORK_SYSCALL_AUDIT …
#define SYSCALL_WORK_SYSCALL_USER_DISPATCH …
#define SYSCALL_WORK_SYSCALL_EXIT_TRAP …
#endif

#include <asm/thread_info.h>

#ifdef __KERNEL__

#ifndef arch_set_restart_data
#define arch_set_restart_data …
#endif

static inline long set_restart_fn(struct restart_block *restart,
					long (*fn)(struct restart_block *))
{ … }

#ifndef THREAD_ALIGN
#define THREAD_ALIGN …
#endif

#define THREADINFO_GFP …

/*
 * flag set/clear/test wrappers
 * - pass TIF_xxxx constants to these functions
 */

static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
{ … }

static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
{ … }

static inline void update_ti_thread_flag(struct thread_info *ti, int flag,
					 bool value)
{ … }

static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
{ … }

static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
{ … }

static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
{ … }

/*
 * This may be used in noinstr code, and needs to be __always_inline to prevent
 * inadvertent instrumentation.
 */
static __always_inline unsigned long read_ti_thread_flags(struct thread_info *ti)
{ … }

#define set_thread_flag(flag) …
#define clear_thread_flag(flag) …
#define update_thread_flag(flag, value) …
#define test_and_set_thread_flag(flag) …
#define test_and_clear_thread_flag(flag) …
#define test_thread_flag(flag) …
#define read_thread_flags() …

#define read_task_thread_flags(t) …

#ifdef CONFIG_GENERIC_ENTRY
#define set_syscall_work(fl) …
#define test_syscall_work(fl) …
#define clear_syscall_work(fl) …

#define set_task_syscall_work(t, fl) …
#define test_task_syscall_work(t, fl) …
#define clear_task_syscall_work(t, fl) …

#else /* CONFIG_GENERIC_ENTRY */

#define set_syscall_work …
#define test_syscall_work …
#define clear_syscall_work …

#define set_task_syscall_work …
#define test_task_syscall_work …
#define clear_task_syscall_work …
#endif /* !CONFIG_GENERIC_ENTRY */

#ifdef _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H

static __always_inline bool tif_need_resched(void)
{ … }

#else

static __always_inline bool tif_need_resched(void)
{
	return test_bit(TIF_NEED_RESCHED,
			(unsigned long *)(&current_thread_info()->flags));
}

#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H */

#ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
static inline int arch_within_stack_frames(const void * const stack,
					   const void * const stackend,
					   const void *obj, unsigned long len)
{
	return 0;
}
#endif

#ifdef CONFIG_HARDENED_USERCOPY
extern void __check_object_size(const void *ptr, unsigned long n,
					bool to_user);

static __always_inline void check_object_size(const void *ptr, unsigned long n,
					      bool to_user)
{ … }
#else
static inline void check_object_size(const void *ptr, unsigned long n,
				     bool to_user)
{ }
#endif /* CONFIG_HARDENED_USERCOPY */

extern void __compiletime_error("copy source size is too small")
__bad_copy_from(void);
extern void __compiletime_error("copy destination size is too small")
__bad_copy_to(void);

void __copy_overflow(int size, unsigned long count);

static inline void copy_overflow(int size, unsigned long count)
{ … }

static __always_inline __must_check bool
check_copy_size(const void *addr, size_t bytes, bool is_source)
{ … }

#ifndef arch_setup_new_exec
static inline void arch_setup_new_exec(void) { }
#endif

void arch_task_cache_init(void); /* for CONFIG_SH */
void arch_release_task_struct(struct task_struct *tsk);
int arch_dup_task_struct(struct task_struct *dst,
				struct task_struct *src);

#endif	/* __KERNEL__ */

#endif /* _LINUX_THREAD_INFO_H */