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 /*
17 * System call restart block.
18 */
19 struct restart_block {
20 long (*fn)(struct restart_block *);
21 union {
22 /* For futex_wait and futex_wait_requeue_pi */
23 struct {
24 u32 __user *uaddr;
25 u32 val;
26 u32 flags;
27 u32 bitset;
28 u64 time;
29 u32 __user *uaddr2;
30 } futex;
31 /* For nanosleep */
32 struct {
33 clockid_t clockid;
34 struct timespec __user *rmtp;
35 #ifdef CONFIG_COMPAT
36 struct compat_timespec __user *compat_rmtp;
37 #endif
38 u64 expires;
39 } nanosleep;
40 /* For poll */
41 struct {
42 struct pollfd __user *ufds;
43 int nfds;
44 int has_timeout;
45 unsigned long tv_sec;
46 unsigned long tv_nsec;
47 } poll;
48 };
49 };
50
51 extern long do_no_restart_syscall(struct restart_block *parm);
52
53 #include <linux/bitops.h>
54 #include <asm/thread_info.h>
55
56 #ifdef __KERNEL__
57
58 #ifdef CONFIG_DEBUG_STACK_USAGE
59 # define THREADINFO_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO)
60 #else
61 # define THREADINFO_GFP (GFP_KERNEL | __GFP_NOTRACK)
62 #endif
63
64 /*
65 * flag set/clear/test wrappers
66 * - pass TIF_xxxx constants to these functions
67 */
68
set_ti_thread_flag(struct thread_info * ti,int flag)69 static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
70 {
71 set_bit(flag, (unsigned long *)&ti->flags);
72 }
73
clear_ti_thread_flag(struct thread_info * ti,int flag)74 static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
75 {
76 clear_bit(flag, (unsigned long *)&ti->flags);
77 }
78
test_and_set_ti_thread_flag(struct thread_info * ti,int flag)79 static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
80 {
81 return test_and_set_bit(flag, (unsigned long *)&ti->flags);
82 }
83
test_and_clear_ti_thread_flag(struct thread_info * ti,int flag)84 static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
85 {
86 return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
87 }
88
test_ti_thread_flag(struct thread_info * ti,int flag)89 static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
90 {
91 return test_bit(flag, (unsigned long *)&ti->flags);
92 }
93
94 #define set_thread_flag(flag) \
95 set_ti_thread_flag(current_thread_info(), flag)
96 #define clear_thread_flag(flag) \
97 clear_ti_thread_flag(current_thread_info(), flag)
98 #define test_and_set_thread_flag(flag) \
99 test_and_set_ti_thread_flag(current_thread_info(), flag)
100 #define test_and_clear_thread_flag(flag) \
101 test_and_clear_ti_thread_flag(current_thread_info(), flag)
102 #define test_thread_flag(flag) \
103 test_ti_thread_flag(current_thread_info(), flag)
104
105 #define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
106
107 #if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK
108 /*
109 * An arch can define its own version of set_restore_sigmask() to get the
110 * job done however works, with or without TIF_RESTORE_SIGMASK.
111 */
112 #define HAVE_SET_RESTORE_SIGMASK 1
113
114 /**
115 * set_restore_sigmask() - make sure saved_sigmask processing gets done
116 *
117 * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
118 * will run before returning to user mode, to process the flag. For
119 * all callers, TIF_SIGPENDING is already set or it's no harm to set
120 * it. TIF_RESTORE_SIGMASK need not be in the set of bits that the
121 * arch code will notice on return to user mode, in case those bits
122 * are scarce. We set TIF_SIGPENDING here to ensure that the arch
123 * signal code always gets run when TIF_RESTORE_SIGMASK is set.
124 */
set_restore_sigmask(void)125 static inline void set_restore_sigmask(void)
126 {
127 set_thread_flag(TIF_RESTORE_SIGMASK);
128 WARN_ON(!test_thread_flag(TIF_SIGPENDING));
129 }
clear_restore_sigmask(void)130 static inline void clear_restore_sigmask(void)
131 {
132 clear_thread_flag(TIF_RESTORE_SIGMASK);
133 }
test_restore_sigmask(void)134 static inline bool test_restore_sigmask(void)
135 {
136 return test_thread_flag(TIF_RESTORE_SIGMASK);
137 }
test_and_clear_restore_sigmask(void)138 static inline bool test_and_clear_restore_sigmask(void)
139 {
140 return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
141 }
142 #endif /* TIF_RESTORE_SIGMASK && !HAVE_SET_RESTORE_SIGMASK */
143
144 #ifndef HAVE_SET_RESTORE_SIGMASK
145 #error "no set_restore_sigmask() provided and default one won't work"
146 #endif
147
148 #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
arch_within_stack_frames(const void * const stack,const void * const stackend,const void * obj,unsigned long len)149 static inline int arch_within_stack_frames(const void * const stack,
150 const void * const stackend,
151 const void *obj, unsigned long len)
152 {
153 return 0;
154 }
155 #endif
156
157 #ifdef CONFIG_HARDENED_USERCOPY
158 extern void __check_object_size(const void *ptr, unsigned long n,
159 bool to_user);
160
check_object_size(const void * ptr,unsigned long n,bool to_user)161 static __always_inline void check_object_size(const void *ptr, unsigned long n,
162 bool to_user)
163 {
164 if (!__builtin_constant_p(n))
165 __check_object_size(ptr, n, to_user);
166 }
167 #else
check_object_size(const void * ptr,unsigned long n,bool to_user)168 static inline void check_object_size(const void *ptr, unsigned long n,
169 bool to_user)
170 { }
171 #endif /* CONFIG_HARDENED_USERCOPY */
172
173 #endif /* __KERNEL__ */
174
175 #endif /* _LINUX_THREAD_INFO_H */
176