include/linux/thread_info.h

   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 struct thread_info {
  18         unsigned long           flags;          /* low level flags */
  19 };
  20
  21 #define INIT_THREAD_INFO(tsk)                   \
  22 {                                               \
  23         .flags          = 0,                    \
  24 }
  25 #endif
  26
  27 #ifdef CONFIG_THREAD_INFO_IN_TASK
  28 #define current_thread_info() ((struct thread_info *)current)
  29 #endif
  30
  31 /*
  32  * System call restart block.
  33  */
  34 struct restart_block {
  35         long (*fn)(struct restart_block *);
  36         union {
  37                 /* For futex_wait and futex_wait_requeue_pi */
  38                 struct {
  39                         u32 __user *uaddr;
  40                         u32 val;
  41                         u32 flags;
  42                         u32 bitset;
  43                         u64 time;
  44                         u32 __user *uaddr2;
  45                 } futex;
  46                 /* For nanosleep */
  47                 struct {
  48                         clockid_t clockid;
  49                         struct timespec __user *rmtp;
  50 #ifdef CONFIG_COMPAT
  51                         struct compat_timespec __user *compat_rmtp;
  52 #endif
  53                         u64 expires;
  54                 } nanosleep;
  55                 /* For poll */
  56                 struct {
  57                         struct pollfd __user *ufds;
  58                         int nfds;
  59                         int has_timeout;
  60                         unsigned long tv_sec;
  61                         unsigned long tv_nsec;
  62                 } poll;
  63         };
  64 };
  65
  66 extern long do_no_restart_syscall(struct restart_block *parm);
  67
  68 #include <linux/bitops.h>
  69 #include <asm/thread_info.h>
  70
  71 #ifdef __KERNEL__
  72
  73 #ifdef CONFIG_DEBUG_STACK_USAGE
  74 # define THREADINFO_GFP         (GFP_KERNEL_ACCOUNT | __GFP_NOTRACK | \
  75                                  __GFP_ZERO)
  76 #else
  77 # define THREADINFO_GFP         (GFP_KERNEL_ACCOUNT | __GFP_NOTRACK)
  78 #endif
  79
  80 /*
  81  * flag set/clear/test wrappers
  82  * - pass TIF_xxxx constants to these functions
  83  */
  84
  85 static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
  86 {
  87         set_bit(flag, (unsigned long *)&ti->flags);
  88 }
  89
  90 static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
  91 {
  92         clear_bit(flag, (unsigned long *)&ti->flags);
  93 }
  94
  95 static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
  96 {
  97         return test_and_set_bit(flag, (unsigned long *)&ti->flags);
  98 }
  99
 100 static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
 101 {
 102         return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
 103 }
 104
 105 static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
 106 {
 107         return test_bit(flag, (unsigned long *)&ti->flags);
 108 }
 109
 110 #define set_thread_flag(flag) \
 111         set_ti_thread_flag(current_thread_info(), flag)
 112 #define clear_thread_flag(flag) \
 113         clear_ti_thread_flag(current_thread_info(), flag)
 114 #define test_and_set_thread_flag(flag) \
 115         test_and_set_ti_thread_flag(current_thread_info(), flag)
 116 #define test_and_clear_thread_flag(flag) \
 117         test_and_clear_ti_thread_flag(current_thread_info(), flag)
 118 #define test_thread_flag(flag) \
 119         test_ti_thread_flag(current_thread_info(), flag)
 120
 121 #define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
 122
 123 #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
 124 static inline int arch_within_stack_frames(const void * const stack,
 125                                            const void * const stackend,
 126                                            const void *obj, unsigned long len)
 127 {
 128         return 0;
 129 }
 130 #endif
 131
 132 #ifdef CONFIG_HARDENED_USERCOPY
 133 extern void __check_object_size(const void *ptr, unsigned long n,
 134                                         bool to_user);
 135
 136 static __always_inline void check_object_size(const void *ptr, unsigned long n,
 137                                               bool to_user)
 138 {
 139         if (!__builtin_constant_p(n))
 140                 __check_object_size(ptr, n, to_user);
 141 }
 142 #else
 143 static inline void check_object_size(const void *ptr, unsigned long n,
 144                                      bool to_user)
 145 { }
 146 #endif /* CONFIG_HARDENED_USERCOPY */
 147
 148 #endif  /* __KERNEL__ */
 149
 150 #endif /* _LINUX_THREAD_INFO_H */