include/asm-x86/thread_info_64.h

   1 /* thread_info.h: x86_64 low-level thread information
   2  *
   3  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
   4  * - Incorporating suggestions made by Linus Torvalds and Dave Miller
   5  */
   6
   7 #ifndef _ASM_THREAD_INFO_H
   8 #define _ASM_THREAD_INFO_H
   9
  10 #ifdef __KERNEL__
  11
  12 #include <asm/page.h>
  13 #include <asm/types.h>
  14 #include <asm/pda.h>
  15
  16 /*
  17  * low level task data that entry.S needs immediate access to
  18  * - this struct should fit entirely inside of one cache line
  19  * - this struct shares the supervisor stack pages
  20  */
  21 #ifndef __ASSEMBLY__
  22 struct task_struct;
  23 struct exec_domain;
  24 #include <asm/processor.h>
  25
  26 struct thread_info {
  27         struct task_struct      *task;          /* main task structure */
  28         struct exec_domain      *exec_domain;   /* execution domain */
  29         __u32                   flags;          /* low level flags */
  30         __u32                   status;         /* thread synchronous flags */
  31         __u32                   cpu;            /* current CPU */
  32         int                     preempt_count;  /* 0 => preemptable,
  33                                                    <0 => BUG */
  34         mm_segment_t            addr_limit;
  35         struct restart_block    restart_block;
  36 #ifdef CONFIG_IA32_EMULATION
  37         void __user             *sysenter_return;
  38 #endif
  39 };
  40 #endif
  41
  42 /*
  43  * macros/functions for gaining access to the thread information structure
  44  * preempt_count needs to be 1 initially, until the scheduler is functional.
  45  */
  46 #ifndef __ASSEMBLY__
  47 #define INIT_THREAD_INFO(tsk)                   \
  48 {                                               \
  49         .task          = &tsk,                  \
  50         .exec_domain   = &default_exec_domain,  \
  51         .flags         = 0,                     \
  52         .cpu           = 0,                     \
  53         .preempt_count = 1,                     \
  54         .addr_limit     = KERNEL_DS,            \
  55         .restart_block = {                      \
  56                 .fn = do_no_restart_syscall,    \
  57         },                                      \
  58 }
  59
  60 #define init_thread_info        (init_thread_union.thread_info)
  61 #define init_stack              (init_thread_union.stack)
  62
  63 static inline struct thread_info *current_thread_info(void)
  64 {
  65         struct thread_info *ti;
  66         ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE);
  67         return ti;
  68 }
  69
  70 /* do not use in interrupt context */
  71 static inline struct thread_info *stack_thread_info(void)
  72 {
  73         struct thread_info *ti;
  74         asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1)));
  75         return ti;
  76 }
  77
  78 /* thread information allocation */
  79 #ifdef CONFIG_DEBUG_STACK_USAGE
  80 #define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO)
  81 #else
  82 #define THREAD_FLAGS GFP_KERNEL
  83 #endif
  84
  85 #define alloc_thread_info(tsk)                                          \
  86         ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER))
  87
  88 #else /* !__ASSEMBLY__ */
  89
  90 /* how to get the thread information struct from ASM */
  91 #define GET_THREAD_INFO(reg) \
  92         movq %gs:pda_kernelstack,reg ; \
  93         subq $(THREAD_SIZE-PDA_STACKOFFSET),reg
  94
  95 #endif
  96
  97 /*
  98  * thread information flags
  99  * - these are process state flags that various assembly files
 100  *   may need to access
 101  * - pending work-to-be-done flags are in LSW
 102  * - other flags in MSW
 103  * Warning: layout of LSW is hardcoded in entry.S
 104  */
 105 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 106 #define TIF_SIGPENDING          2       /* signal pending */
 107 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 108 #define TIF_SINGLESTEP          4       /* reenable singlestep on user return*/
 109 #define TIF_IRET                5       /* force IRET */
 110 #define TIF_SYSCALL_AUDIT       7       /* syscall auditing active */
 111 #define TIF_SECCOMP             8       /* secure computing */
 112 #define TIF_MCE_NOTIFY          10      /* notify userspace of an MCE */
 113 #define TIF_HRTICK_RESCHED      11      /* reprogram hrtick timer */
 114 /* 16 free */
 115 #define TIF_IA32                17      /* 32bit process */
 116 #define TIF_FORK                18      /* ret_from_fork */
 117 #define TIF_ABI_PENDING         19
 118 #define TIF_MEMDIE              20
 119 #define TIF_DEBUG               21      /* uses debug registers */
 120 #define TIF_IO_BITMAP           22      /* uses I/O bitmap */
 121 #define TIF_FREEZE              23      /* is freezing for suspend */
 122 #define TIF_FORCED_TF           24      /* true if TF in eflags artificially */
 123 #define TIF_DEBUGCTLMSR         25      /* uses thread_struct.debugctlmsr */
 124 #define TIF_DS_AREA_MSR         26      /* uses thread_struct.ds_area_msr */
 125 #define TIF_BTS_TRACE_TS        27      /* record scheduling event timestamps */
 126 #define TIF_NOTSC               28      /* TSC is not accessible in userland */
 127
 128 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
 129 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 130 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
 131 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 132 #define _TIF_IRET               (1 << TIF_IRET)
 133 #define _TIF_SYSCALL_AUDIT      (1 << TIF_SYSCALL_AUDIT)
 134 #define _TIF_SECCOMP            (1 << TIF_SECCOMP)
 135 #define _TIF_MCE_NOTIFY         (1 << TIF_MCE_NOTIFY)
 136 #define _TIF_HRTICK_RESCHED     (1 << TIF_HRTICK_RESCHED)
 137 #define _TIF_IA32               (1 << TIF_IA32)
 138 #define _TIF_FORK               (1 << TIF_FORK)
 139 #define _TIF_ABI_PENDING        (1 << TIF_ABI_PENDING)
 140 #define _TIF_DEBUG              (1 << TIF_DEBUG)
 141 #define _TIF_IO_BITMAP          (1 << TIF_IO_BITMAP)
 142 #define _TIF_FREEZE             (1 << TIF_FREEZE)
 143 #define _TIF_FORCED_TF          (1 << TIF_FORCED_TF)
 144 #define _TIF_DEBUGCTLMSR        (1 << TIF_DEBUGCTLMSR)
 145 #define _TIF_DS_AREA_MSR        (1 << TIF_DS_AREA_MSR)
 146 #define _TIF_BTS_TRACE_TS       (1 << TIF_BTS_TRACE_TS)
 147 #define _TIF_NOTSC              (1 << TIF_NOTSC)
 148
 149 /* work to do on interrupt/exception return */
 150 #define _TIF_WORK_MASK                                                  \
 151         (0x0000FFFF &                                                   \
 152          ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP|_TIF_SECCOMP))
 153 /* work to do on any return to user space */
 154 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
 155
 156 #define _TIF_DO_NOTIFY_MASK                                             \
 157         (_TIF_SIGPENDING|_TIF_SINGLESTEP|_TIF_MCE_NOTIFY|_TIF_HRTICK_RESCHED)
 158
 159 /* flags to check in __switch_to() */
 160 #define _TIF_WORK_CTXSW                                                 \
 161         (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_BTS_TRACE_TS|_TIF_NOTSC)
 162 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
 163 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG)
 164
 165 #define PREEMPT_ACTIVE     0x10000000
 166
 167 /*
 168  * Thread-synchronous status.
 169  *
 170  * This is different from the flags in that nobody else
 171  * ever touches our thread-synchronous status, so we don't
 172  * have to worry about atomic accesses.
 173  */
 174 #define TS_USEDFPU              0x0001  /* FPU was used by this task
 175                                            this quantum (SMP) */
 176 #define TS_COMPAT               0x0002  /* 32bit syscall active */
 177 #define TS_POLLING              0x0004  /* true if in idle loop
 178                                            and not sleeping */
 179 #define TS_RESTORE_SIGMASK      0x0008  /* restore signal mask in do_signal() */
 180
 181 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
 182
 183 #ifndef __ASSEMBLY__
 184 #define HAVE_SET_RESTORE_SIGMASK        1
 185 static inline void set_restore_sigmask(void)
 186 {
 187         struct thread_info *ti = current_thread_info();
 188         ti->status |= TS_RESTORE_SIGMASK;
 189         set_bit(TIF_SIGPENDING, &ti->flags);
 190 }
 191 #endif  /* !__ASSEMBLY__ */
 192
 193 #endif /* __KERNEL__ */
 194
 195 #endif /* _ASM_THREAD_INFO_H */