kernel/include/linux/thread_info.h
2024-07-22 17:22:30 +08:00

243 lines
6.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* thread_info.h: common low-level thread information accessors
*
* Copyright (C) 2002 David Howells (dhowells@redhat.com)
* - 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() ((struct thread_info *)current)
#endif
#include <linux/bitops.h>
/*
* For per-arch arch_within_stack_frames() implementations, defined in
* asm/thread_info.h.
*/
enum {
BAD_STACK = -1,
NOT_STACK = 0,
GOOD_FRAME,
GOOD_STACK,
};
#ifdef CONFIG_GENERIC_ENTRY
enum syscall_work_bit {
SYSCALL_WORK_BIT_SECCOMP,
SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT,
SYSCALL_WORK_BIT_SYSCALL_TRACE,
SYSCALL_WORK_BIT_SYSCALL_EMU,
SYSCALL_WORK_BIT_SYSCALL_AUDIT,
SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH,
SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP,
};
#define SYSCALL_WORK_SECCOMP BIT(SYSCALL_WORK_BIT_SECCOMP)
#define SYSCALL_WORK_SYSCALL_TRACEPOINT BIT(SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT)
#define SYSCALL_WORK_SYSCALL_TRACE BIT(SYSCALL_WORK_BIT_SYSCALL_TRACE)
#define SYSCALL_WORK_SYSCALL_EMU BIT(SYSCALL_WORK_BIT_SYSCALL_EMU)
#define SYSCALL_WORK_SYSCALL_AUDIT BIT(SYSCALL_WORK_BIT_SYSCALL_AUDIT)
#define SYSCALL_WORK_SYSCALL_USER_DISPATCH BIT(SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH)
#define SYSCALL_WORK_SYSCALL_EXIT_TRAP BIT(SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP)
#endif
#include <asm/thread_info.h>
#ifdef __KERNEL__
#ifndef arch_set_restart_data
#define arch_set_restart_data(restart) do { } while (0)
#endif
static inline long set_restart_fn(struct restart_block *restart,
long (*fn)(struct restart_block *))
{
restart->fn = fn;
arch_set_restart_data(restart);
return -ERESTART_RESTARTBLOCK;
}
#ifndef THREAD_ALIGN
#define THREAD_ALIGN THREAD_SIZE
#endif
#define THREADINFO_GFP (GFP_KERNEL_ACCOUNT | __GFP_ZERO)
/*
* 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)
{
set_bit(flag, (unsigned long *)&ti->flags);
}
static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
{
clear_bit(flag, (unsigned long *)&ti->flags);
}
static inline void update_ti_thread_flag(struct thread_info *ti, int flag,
bool value)
{
if (value)
set_ti_thread_flag(ti, flag);
else
clear_ti_thread_flag(ti, flag);
}
static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
{
return test_and_set_bit(flag, (unsigned long *)&ti->flags);
}
static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
{
return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
}
static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
{
return test_bit(flag, (unsigned long *)&ti->flags);
}
/*
* 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)
{
return READ_ONCE(ti->flags);
}
#define set_thread_flag(flag) \
set_ti_thread_flag(current_thread_info(), flag)
#define clear_thread_flag(flag) \
clear_ti_thread_flag(current_thread_info(), flag)
#define update_thread_flag(flag, value) \
update_ti_thread_flag(current_thread_info(), flag, value)
#define test_and_set_thread_flag(flag) \
test_and_set_ti_thread_flag(current_thread_info(), flag)
#define test_and_clear_thread_flag(flag) \
test_and_clear_ti_thread_flag(current_thread_info(), flag)
#define test_thread_flag(flag) \
test_ti_thread_flag(current_thread_info(), flag)
#define read_thread_flags() \
read_ti_thread_flags(current_thread_info())
#define read_task_thread_flags(t) \
read_ti_thread_flags(task_thread_info(t))
#ifdef CONFIG_GENERIC_ENTRY
#define set_syscall_work(fl) \
set_bit(SYSCALL_WORK_BIT_##fl, &current_thread_info()->syscall_work)
#define test_syscall_work(fl) \
test_bit(SYSCALL_WORK_BIT_##fl, &current_thread_info()->syscall_work)
#define clear_syscall_work(fl) \
clear_bit(SYSCALL_WORK_BIT_##fl, &current_thread_info()->syscall_work)
#define set_task_syscall_work(t, fl) \
set_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
#define test_task_syscall_work(t, fl) \
test_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
#define clear_task_syscall_work(t, fl) \
clear_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
#else /* CONFIG_GENERIC_ENTRY */
#define set_syscall_work(fl) \
set_ti_thread_flag(current_thread_info(), TIF_##fl)
#define test_syscall_work(fl) \
test_ti_thread_flag(current_thread_info(), TIF_##fl)
#define clear_syscall_work(fl) \
clear_ti_thread_flag(current_thread_info(), TIF_##fl)
#define set_task_syscall_work(t, fl) \
set_ti_thread_flag(task_thread_info(t), TIF_##fl)
#define test_task_syscall_work(t, fl) \
test_ti_thread_flag(task_thread_info(t), TIF_##fl)
#define clear_task_syscall_work(t, fl) \
clear_ti_thread_flag(task_thread_info(t), TIF_##fl)
#endif /* !CONFIG_GENERIC_ENTRY */
#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
#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)
{
if (!__builtin_constant_p(n))
__check_object_size(ptr, n, 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);
static inline void copy_overflow(int size, unsigned long count)
{
WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
}
static __always_inline __must_check bool
check_copy_size(const void *addr, size_t bytes, bool is_source)
{
int sz = __compiletime_object_size(addr);
if (unlikely(sz >= 0 && sz < bytes)) {
if (!__builtin_constant_p(bytes))
copy_overflow(sz, bytes);
else if (is_source)
__bad_copy_from();
else
__bad_copy_to();
return false;
}
if (WARN_ON_ONCE(bytes > INT_MAX))
return false;
check_object_size(addr, bytes, is_source);
return true;
}
#ifndef arch_setup_new_exec
static inline void arch_setup_new_exec(void) { }
#endif
#endif /* __KERNEL__ */
#endif /* _LINUX_THREAD_INFO_H */