include/linux/thread_info.h - third_party/kernel - Git at Google

 /* 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 */
	/* 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 */