[linux-block.git] / 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 (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);
}

#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)

#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 */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
1da177e4 LT	2	/* thread_info.h: common low-level thread information accessors
	3	*
	4	* Copyright (C) 2002 David Howells (dhowells@redhat.com)
	5	* - Incorporating suggestions made by Linus Torvalds
	6	*/
	7
	8	#ifndef _LINUX_THREAD_INFO_H
	9	#define _LINUX_THREAD_INFO_H
	10
ce6bd420	11	#include <linux/types.h>
f39650de	12	#include <linux/limits.h>
edd63a27	13	#include <linux/bug.h>
53d74d05	14	#include <linux/restart_block.h>
5abbe51a	15	#include <linux/errno.h>
a332d86d	16
c65eacbe	17	#ifdef CONFIG_THREAD_INFO_IN_TASK
dc3d2a67 MR	18	/*
	19	* For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
	20	* definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
	21	* including <asm/current.h> can cause a circular dependency on some platforms.
	22	*/
	23	#include <asm/current.h>
c65eacbe AL	24	#define current_thread_info() ((struct thread_info *)current)
	25	#endif
	26
1da177e4	27	#include <linux/bitops.h>
96dc4f9f S	28
	29	/*
	30	* For per-arch arch_within_stack_frames() implementations, defined in
	31	* asm/thread_info.h.
	32	*/
	33	enum {
	34	BAD_STACK = -1,
	35	NOT_STACK = 0,
	36	GOOD_FRAME,
	37	GOOD_STACK,
	38	};
	39
5903f61e	40	#ifdef CONFIG_GENERIC_ENTRY
23d67a54 GKB	41	enum syscall_work_bit {
23d67a54 GKB	42	SYSCALL_WORK_BIT_SECCOMP,
524666cb	43	SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT,
64c19ba2	44	SYSCALL_WORK_BIT_SYSCALL_TRACE,
64eb35f7	45	SYSCALL_WORK_BIT_SYSCALL_EMU,
785dc4eb	46	SYSCALL_WORK_BIT_SYSCALL_AUDIT,
1446e1df	47	SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH,
6342adca	48	SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP,
23d67a54 GKB	49	};
	50
	51	#define SYSCALL_WORK_SECCOMP BIT(SYSCALL_WORK_BIT_SECCOMP)
524666cb	52	#define SYSCALL_WORK_SYSCALL_TRACEPOINT BIT(SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT)
64c19ba2	53	#define SYSCALL_WORK_SYSCALL_TRACE BIT(SYSCALL_WORK_BIT_SYSCALL_TRACE)
64eb35f7	54	#define SYSCALL_WORK_SYSCALL_EMU BIT(SYSCALL_WORK_BIT_SYSCALL_EMU)
785dc4eb	55	#define SYSCALL_WORK_SYSCALL_AUDIT BIT(SYSCALL_WORK_BIT_SYSCALL_AUDIT)
1446e1df	56	#define SYSCALL_WORK_SYSCALL_USER_DISPATCH BIT(SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH)
6342adca	57	#define SYSCALL_WORK_SYSCALL_EXIT_TRAP BIT(SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP)
5903f61e	58	#endif
23d67a54	59
1da177e4 LT	60	#include <asm/thread_info.h>
	61
	62	#ifdef __KERNEL__
	63
5abbe51a ON	64	#ifndef arch_set_restart_data
	65	#define arch_set_restart_data(restart) do { } while (0)
	66	#endif
	67
	68	static inline long set_restart_fn(struct restart_block *restart,
	69	long (fn)(struct restart_block ))
	70	{
	71	restart->fn = fn;
	72	arch_set_restart_data(restart);
	73	return -ERESTART_RESTARTBLOCK;
	74	}
	75
48ac3c18 MR	76	#ifndef THREAD_ALIGN
	77	#define THREAD_ALIGN THREAD_SIZE
	78	#endif
	79
e01e8063	80	#define THREADINFO_GFP (GFP_KERNEL_ACCOUNT \| __GFP_ZERO)
2889f608	81
1da177e4 LT	82	/*
	83	* flag set/clear/test wrappers
	84	* - pass TIF_xxxx constants to these functions
	85	*/
	86
1da177e4 LT	87	static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
1da177e4 LT	88	{
5548fecd	89	set_bit(flag, (unsigned long *)&ti->flags);
1da177e4 LT	90	}
	91
	92	static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
	93	{
5548fecd	94	clear_bit(flag, (unsigned long *)&ti->flags);
1da177e4 LT	95	}
1da177e4 LT	96
93ee37c2 DM	97	static inline void update_ti_thread_flag(struct thread_info *ti, int flag,
	98	bool value)
	99	{
	100	if (value)
	101	set_ti_thread_flag(ti, flag);
	102	else
	103	clear_ti_thread_flag(ti, flag);
	104	}
	105
1da177e4 LT	106	static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
1da177e4 LT	107	{
5548fecd	108	return test_and_set_bit(flag, (unsigned long *)&ti->flags);
1da177e4 LT	109	}
	110
	111	static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
	112	{
5548fecd	113	return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
1da177e4 LT	114	}
	115
	116	static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
	117	{
5548fecd	118	return test_bit(flag, (unsigned long *)&ti->flags);
1da177e4 LT	119	}
1da177e4 LT	120
3b66a1ed RZ	121	#define set_thread_flag(flag) \
	122	set_ti_thread_flag(current_thread_info(), flag)
	123	#define clear_thread_flag(flag) \
	124	clear_ti_thread_flag(current_thread_info(), flag)
93ee37c2 DM	125	#define update_thread_flag(flag, value) \
93ee37c2 DM	126	update_ti_thread_flag(current_thread_info(), flag, value)
3b66a1ed RZ	127	#define test_and_set_thread_flag(flag) \
	128	test_and_set_ti_thread_flag(current_thread_info(), flag)
	129	#define test_and_clear_thread_flag(flag) \
	130	test_and_clear_ti_thread_flag(current_thread_info(), flag)
	131	#define test_thread_flag(flag) \
	132	test_ti_thread_flag(current_thread_info(), flag)
	133
3136b93c GKB	134	#ifdef CONFIG_GENERIC_ENTRY
	135	#define set_syscall_work(fl) \
	136	set_bit(SYSCALL_WORK_BIT_##fl, &current_thread_info()->syscall_work)
	137	#define test_syscall_work(fl) \
	138	test_bit(SYSCALL_WORK_BIT_##fl, &current_thread_info()->syscall_work)
	139	#define clear_syscall_work(fl) \
	140	clear_bit(SYSCALL_WORK_BIT_##fl, &current_thread_info()->syscall_work)
	141
	142	#define set_task_syscall_work(t, fl) \
	143	set_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
	144	#define test_task_syscall_work(t, fl) \
	145	test_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
	146	#define clear_task_syscall_work(t, fl) \
	147	clear_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
	148
	149	#else /* CONFIG_GENERIC_ENTRY */
	150
	151	#define set_syscall_work(fl) \
5903f61e	152	set_ti_thread_flag(current_thread_info(), TIF_##fl)
3136b93c	153	#define test_syscall_work(fl) \
5903f61e	154	test_ti_thread_flag(current_thread_info(), TIF_##fl)
3136b93c	155	#define clear_syscall_work(fl) \
5903f61e	156	clear_ti_thread_flag(current_thread_info(), TIF_##fl)
3136b93c GKB	157
	158	#define set_task_syscall_work(t, fl) \
	159	set_ti_thread_flag(task_thread_info(t), TIF_##fl)
	160	#define test_task_syscall_work(t, fl) \
	161	test_ti_thread_flag(task_thread_info(t), TIF_##fl)
	162	#define clear_task_syscall_work(t, fl) \
	163	clear_ti_thread_flag(task_thread_info(t), TIF_##fl)
	164	#endif /* !CONFIG_GENERIC_ENTRY */
	165
ea811747 PZ	166	#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
ea811747 PZ	167
0f60a8ef KC	168	#ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
	169	static inline int arch_within_stack_frames(const void * const stack,
	170	const void * const stackend,
	171	const void *obj, unsigned long len)
	172	{
	173	return 0;
	174	}
	175	#endif
	176
f5509cc1 KC	177	#ifdef CONFIG_HARDENED_USERCOPY
	178	extern void __check_object_size(const void *ptr, unsigned long n,
	179	bool to_user);
	180
a85d6b82 KC	181	static __always_inline void check_object_size(const void *ptr, unsigned long n,
a85d6b82 KC	182	bool to_user)
f5509cc1	183	{
81409e9e KC	184	if (!__builtin_constant_p(n))
81409e9e KC	185	__check_object_size(ptr, n, to_user);
f5509cc1 KC	186	}
	187	#else
	188	static inline void check_object_size(const void *ptr, unsigned long n,
	189	bool to_user)
	190	{ }
	191	#endif /* CONFIG_HARDENED_USERCOPY */
	192
b0377fed AV	193	extern void __compiletime_error("copy source size is too small")
	194	__bad_copy_from(void);
	195	extern void __compiletime_error("copy destination size is too small")
	196	__bad_copy_to(void);
	197
	198	static inline void copy_overflow(int size, unsigned long count)
	199	{
	200	WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
	201	}
	202
9dd819a1	203	static __always_inline __must_check bool
b0377fed AV	204	check_copy_size(const void *addr, size_t bytes, bool is_source)
	205	{
	206	int sz = __compiletime_object_size(addr);
	207	if (unlikely(sz >= 0 && sz < bytes)) {
	208	if (!__builtin_constant_p(bytes))
	209	copy_overflow(sz, bytes);
	210	else if (is_source)
	211	__bad_copy_from();
	212	else
	213	__bad_copy_to();
	214	return false;
	215	}
6d13de14 KC	216	if (WARN_ON_ONCE(bytes > INT_MAX))
6d13de14 KC	217	return false;
b0377fed AV	218	check_object_size(addr, bytes, is_source);
	219	return true;
	220	}
	221
e9ea1e7f KH	222	#ifndef arch_setup_new_exec
	223	static inline void arch_setup_new_exec(void) { }
	224	#endif
	225
4e4c22c7	226	#endif /* __KERNEL__ */
1da177e4 LT	227
1da177e4 LT	228	#endif /* _LINUX_THREAD_INFO_H */