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         unsigned long           flags;          /* low level flags */
  52         __u32                   cpu;            /* current CPU */
  53         __s32                   preempt_count; /* 0 => preemptable, <0 => BUG */
  54
  55         mm_segment_t            addr_limit; /* thread address space:
  56                                                0-0x7FFFFFFF for user-thead
  57                                                0-0xFFFFFFFF for kernel-thread
  58                                              */
  59         __u8                    supervisor_stack[0];
  60
  61         /* saved context data */
  62         unsigned long           ksp;
  63 };
  64 #endif
  65
  66 /*
  67  * macros/functions for gaining access to the thread information structure
  68  *
  69  * preempt_count needs to be 1 initially, until the scheduler is functional.
  70  */
  71 #ifndef __ASSEMBLY__
  72 #define INIT_THREAD_INFO(tsk)                           \
  73 {                                                       \
  74         .task           = &tsk,                         \
  75         .flags          = 0,                            \
  76         .cpu            = 0,                            \
  77         .preempt_count  = 1,                            \
  78         .addr_limit     = KERNEL_DS,                    \
  79         .ksp            = 0,                            \
  80 }
  81
  82 #define init_thread_info        (init_thread_union.thread_info)
  83
  84 /* how to get the thread information struct from C */
  85 register struct thread_info *current_thread_info_reg asm("r10");
  86 #define current_thread_info()   (current_thread_info_reg)
  87
  88 #define get_thread_info(ti) get_task_struct((ti)->task)
  89 #define put_thread_info(ti) put_task_struct((ti)->task)
  90
  91 #endif /* !__ASSEMBLY__ */
  92
  93 /*
  94  * thread information flags
  95  *   these are process state flags that various assembly files may need to
  96  *   access
  97  *   - pending work-to-be-done flags are in LSW
  98  *   - other flags in MSW
  99  */
 100 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 101 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 102 #define TIF_SIGPENDING          2       /* signal pending */
 103 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 104 #define TIF_SINGLESTEP          4       /* restore singlestep on return to user
 105                                          * mode
 106                                          */
 107 #define TIF_SYSCALL_TRACEPOINT  8       /* for ftrace syscall instrumentation */
 108 #define TIF_RESTORE_SIGMASK     9
 109 #define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling                                                * TIF_NEED_RESCHED
 110                                          */
 111 #define TIF_MEMDIE              17
 112
 113 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 114 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
 115 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 116 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 117 #define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 118 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
 119
 120
 121 /* Work to do when returning from interrupt/exception */
 122 /* For OpenRISC, this is anything in the LSW other than syscall trace */
 123 #define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP))
 124
 125 #endif /* __KERNEL__ */
 126
 127 #endif /* _ASM_THREAD_INFO_H */