arch/openrisc/include/asm/thread_info.h

   1 /*
   2  * OpenRISC Linux
   3  *
   4  * Linux architectural port borrowing liberally from similar works of
   5  * others.  All original copyrights apply as per the original source
   6  * declaration.
   7  *
   8  * OpenRISC implementation:
   9  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
  10  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
  11  * et al.
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  */
  18
  19 #ifndef _ASM_THREAD_INFO_H
  20 #define _ASM_THREAD_INFO_H
  21
  22 #ifdef __KERNEL__
  23
  24 #ifndef __ASSEMBLY__
  25 #include <asm/types.h>
  26 #include <asm/processor.h>
  27 #endif
  28
  29
  30 /* THREAD_SIZE is the size of the task_struct/kernel_stack combo.
  31  * normally, the stack is found by doing something like p + THREAD_SIZE
  32  * in or32, a page is 8192 bytes, which seems like a sane size
  33  */
  34
  35 #define THREAD_SIZE_ORDER 0
  36 #define THREAD_SIZE       (PAGE_SIZE << THREAD_SIZE_ORDER)
  37
  38 /*
  39  * low level task data that entry.S needs immediate access to
  40  * - this struct should fit entirely inside of one cache line
  41  * - this struct shares the supervisor stack pages
  42  * - if the contents of this structure are changed, the assembly constants
  43  *   must also be changed
  44  */
  45 #ifndef __ASSEMBLY__
  46
  47 typedef unsigned long mm_segment_t;
  48
  49 struct thread_info {
  50         struct task_struct      *task;          /* main task structure */
  51         struct exec_domain      *exec_domain;   /* execution domain */
  52         unsigned long           flags;          /* low level flags */
  53         __u32                   cpu;            /* current CPU */
  54         __s32                   preempt_count; /* 0 => preemptable, <0 => BUG */
  55
  56         mm_segment_t            addr_limit; /* thread address space:
  57                                                0-0x7FFFFFFF for user-thead
  58                                                0-0xFFFFFFFF for kernel-thread
  59                                              */
  60         struct restart_block    restart_block;
  61         __u8                    supervisor_stack[0];
  62
  63         /* saved context data */
  64         unsigned long           ksp;
  65 };
  66 #endif
  67
  68 /*
  69  * macros/functions for gaining access to the thread information structure
  70  *
  71  * preempt_count needs to be 1 initially, until the scheduler is functional.
  72  */
  73 #ifndef __ASSEMBLY__
  74 #define INIT_THREAD_INFO(tsk)                           \
  75 {                                                       \
  76         .task           = &tsk,                         \
  77         .exec_domain    = &default_exec_domain,         \
  78         .flags          = 0,                            \
  79         .cpu            = 0,                            \
  80         .preempt_count  = 1,                            \
  81         .addr_limit     = KERNEL_DS,                    \
  82         .restart_block  = {                             \
  83                           .fn = do_no_restart_syscall,  \
  84         },                                              \
  85         .ksp            = 0,                            \
  86 }
  87
  88 #define init_thread_info        (init_thread_union.thread_info)
  89
  90 /* how to get the thread information struct from C */
  91 register struct thread_info *current_thread_info_reg asm("r10");
  92 #define current_thread_info()   (current_thread_info_reg)
  93
  94 #define get_thread_info(ti) get_task_struct((ti)->task)
  95 #define put_thread_info(ti) put_task_struct((ti)->task)
  96
  97 #endif /* !__ASSEMBLY__ */
  98
  99 /*
 100  * thread information flags
 101  *   these are process state flags that various assembly files may need to
 102  *   access
 103  *   - pending work-to-be-done flags are in LSW
 104  *   - other flags in MSW
 105  */
 106 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 107 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 108 #define TIF_SIGPENDING          2       /* signal pending */
 109 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 110 #define TIF_SINGLESTEP          4       /* restore singlestep on return to user
 111                                          * mode
 112                                          */
 113 #define TIF_SYSCALL_TRACEPOINT  8       /* for ftrace syscall instrumentation */
 114 #define TIF_RESTORE_SIGMASK     9
 115 #define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling                                                * TIF_NEED_RESCHED
 116                                          */
 117 #define TIF_MEMDIE              17
 118
 119 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 120 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
 121 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 122 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 123 #define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 124 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
 125
 126
 127 /* Work to do when returning from interrupt/exception */
 128 /* For OpenRISC, this is anything in the LSW other than syscall trace */
 129 #define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP))
 130
 131 #define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
 132
 133 #endif /* __KERNEL__ */
 134
 135 #endif /* _ASM_THREAD_INFO_H */