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        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 */
  91register 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#endif /* __KERNEL__ */
 132
 133#endif /* _ASM_THREAD_INFO_H */
 134