LXR linux/arch/openrisc/include/asm/thread

   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
  47typedef unsigned long mm_segment_t;
  48
  49struct 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  = INIT_PREEMPT_COUNT,           \
  78        .addr_limit     = KERNEL_DS,                    \
  79        .ksp            = 0,                            \
  80}
  81
  82/* how to get the thread information struct from C */
  83register struct thread_info *current_thread_info_reg asm("r10");
  84#define current_thread_info()   (current_thread_info_reg)
  85
  86#define get_thread_info(ti) get_task_struct((ti)->task)
  87#define put_thread_info(ti) put_task_struct((ti)->task)
  88
  89#endif /* !__ASSEMBLY__ */
  90
  91/*
  92 * thread information flags
  93 *   these are process state flags that various assembly files may need to
  94 *   access
  95 *   - pending work-to-be-done flags are in LSW
  96 *   - other flags in MSW
  97 */
  98#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
  99#define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 100#define TIF_SIGPENDING          2       /* signal pending */
 101#define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 102#define TIF_SINGLESTEP          4       /* restore singlestep on return to user
 103                                         * mode
 104                                         */
 105#define TIF_SYSCALL_TRACEPOINT  8       /* for ftrace syscall instrumentation */
 106#define TIF_RESTORE_SIGMASK     9
 107#define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling                                                * TIF_NEED_RESCHED
 108                                         */
 109#define TIF_MEMDIE              17
 110
 111#define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 112#define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
 113#define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 114#define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 115#define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 116#define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
 117
 118
 119/* Work to do when returning from interrupt/exception */
 120/* For OpenRISC, this is anything in the LSW other than syscall trace */
 121#define _TIF_WORK_MASK (0xff & ~(_TIF_SYSCALL_TRACE|_TIF_SINGLESTEP))
 122
 123#endif /* __KERNEL__ */
 124
 125#endif /* _ASM_THREAD_INFO_H */
 126