xref: /linux/include/linux/thread_info.h (revision 7c66e12136c2fa421ae75497e02728f252108a1b)
1 /* thread_info.h: common low-level thread information accessors
2  *
3  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
4  * - Incorporating suggestions made by Linus Torvalds
5  */
6 
7 #ifndef _LINUX_THREAD_INFO_H
8 #define _LINUX_THREAD_INFO_H
9 
10 #include <linux/types.h>
11 #include <linux/bug.h>
12 
13 struct timespec;
14 struct compat_timespec;
15 
16 #ifdef CONFIG_THREAD_INFO_IN_TASK
17 #define current_thread_info() ((struct thread_info *)current)
18 #endif
19 
20 /*
21  * System call restart block.
22  */
23 struct restart_block {
24 	long (*fn)(struct restart_block *);
25 	union {
26 		/* For futex_wait and futex_wait_requeue_pi */
27 		struct {
28 			u32 __user *uaddr;
29 			u32 val;
30 			u32 flags;
31 			u32 bitset;
32 			u64 time;
33 			u32 __user *uaddr2;
34 		} futex;
35 		/* For nanosleep */
36 		struct {
37 			clockid_t clockid;
38 			struct timespec __user *rmtp;
39 #ifdef CONFIG_COMPAT
40 			struct compat_timespec __user *compat_rmtp;
41 #endif
42 			u64 expires;
43 		} nanosleep;
44 		/* For poll */
45 		struct {
46 			struct pollfd __user *ufds;
47 			int nfds;
48 			int has_timeout;
49 			unsigned long tv_sec;
50 			unsigned long tv_nsec;
51 		} poll;
52 	};
53 };
54 
55 extern long do_no_restart_syscall(struct restart_block *parm);
56 
57 #include <linux/bitops.h>
58 #include <asm/thread_info.h>
59 
60 #ifdef __KERNEL__
61 
62 #ifdef CONFIG_DEBUG_STACK_USAGE
63 # define THREADINFO_GFP		(GFP_KERNEL_ACCOUNT | __GFP_NOTRACK | \
64 				 __GFP_ZERO)
65 #else
66 # define THREADINFO_GFP		(GFP_KERNEL_ACCOUNT | __GFP_NOTRACK)
67 #endif
68 
69 /*
70  * flag set/clear/test wrappers
71  * - pass TIF_xxxx constants to these functions
72  */
73 
74 static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
75 {
76 	set_bit(flag, (unsigned long *)&ti->flags);
77 }
78 
79 static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
80 {
81 	clear_bit(flag, (unsigned long *)&ti->flags);
82 }
83 
84 static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
85 {
86 	return test_and_set_bit(flag, (unsigned long *)&ti->flags);
87 }
88 
89 static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
90 {
91 	return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
92 }
93 
94 static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
95 {
96 	return test_bit(flag, (unsigned long *)&ti->flags);
97 }
98 
99 #define set_thread_flag(flag) \
100 	set_ti_thread_flag(current_thread_info(), flag)
101 #define clear_thread_flag(flag) \
102 	clear_ti_thread_flag(current_thread_info(), flag)
103 #define test_and_set_thread_flag(flag) \
104 	test_and_set_ti_thread_flag(current_thread_info(), flag)
105 #define test_and_clear_thread_flag(flag) \
106 	test_and_clear_ti_thread_flag(current_thread_info(), flag)
107 #define test_thread_flag(flag) \
108 	test_ti_thread_flag(current_thread_info(), flag)
109 
110 #define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
111 
112 #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
113 static inline int arch_within_stack_frames(const void * const stack,
114 					   const void * const stackend,
115 					   const void *obj, unsigned long len)
116 {
117 	return 0;
118 }
119 #endif
120 
121 #ifdef CONFIG_HARDENED_USERCOPY
122 extern void __check_object_size(const void *ptr, unsigned long n,
123 					bool to_user);
124 
125 static __always_inline void check_object_size(const void *ptr, unsigned long n,
126 					      bool to_user)
127 {
128 	if (!__builtin_constant_p(n))
129 		__check_object_size(ptr, n, to_user);
130 }
131 #else
132 static inline void check_object_size(const void *ptr, unsigned long n,
133 				     bool to_user)
134 { }
135 #endif /* CONFIG_HARDENED_USERCOPY */
136 
137 #endif	/* __KERNEL__ */
138 
139 #endif /* _LINUX_THREAD_INFO_H */
140