LXR linux/include/asm-arm/thread

   1/*
   2 *  linux/include/asm-arm/thread_info.h
   3 *
   4 *  Copyright (C) 2002 Russell King.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 */
  10#ifndef __ASM_ARM_THREAD_INFO_H
  11#define __ASM_ARM_THREAD_INFO_H
  12
  13#ifdef __KERNEL__
  14
  15#include <linux/compiler.h>
  16#include <asm/fpstate.h>
  17
  18#define THREAD_SIZE_ORDER       1
  19#define THREAD_SIZE             8192
  20#define THREAD_START_SP         (THREAD_SIZE - 8)
  21
  22#ifndef __ASSEMBLY__
  23
  24struct task_struct;
  25struct exec_domain;
  26
  27#include <asm/types.h>
  28#include <asm/domain.h>
  29
  30typedef unsigned long mm_segment_t;
  31
  32struct cpu_context_save {
  33        __u32   r4;
  34        __u32   r5;
  35        __u32   r6;
  36        __u32   r7;
  37        __u32   r8;
  38        __u32   r9;
  39        __u32   sl;
  40        __u32   fp;
  41        __u32   sp;
  42        __u32   pc;
  43        __u32   extra[2];               /* Xscale 'acc' register, etc */
  44};
  45
  46/*
  47 * low level task data that entry.S needs immediate access to.
  48 * __switch_to() assumes cpu_context follows immediately after cpu_domain.
  49 */
  50struct thread_info {
  51        unsigned long           flags;          /* low level flags */
  52        int                     preempt_count;  /* 0 => preemptable, <0 => bug */
  53        mm_segment_t            addr_limit;     /* address limit */
  54        struct task_struct      *task;          /* main task structure */
  55        struct exec_domain      *exec_domain;   /* execution domain */
  56        __u32                   cpu;            /* cpu */
  57        __u32                   cpu_domain;     /* cpu domain */
  58        struct cpu_context_save cpu_context;    /* cpu context */
  59        __u32                   syscall;        /* syscall number */
  60        __u8                    used_cp[16];    /* thread used copro */
  61        unsigned long           tp_value;
  62        struct crunch_state     crunchstate;
  63        union fp_state          fpstate __attribute__((aligned(8)));
  64        union vfp_state         vfpstate;
  65        struct restart_block    restart_block;
  66};
  67
  68#define INIT_THREAD_INFO(tsk)                                           \
  69{                                                                       \
  70        .task           = &tsk,                                         \
  71        .exec_domain    = &default_exec_domain,                         \
  72        .flags          = 0,                                            \
  73        .preempt_count  = 1,                                            \
  74        .addr_limit     = KERNEL_DS,                                    \
  75        .cpu_domain     = domain_val(DOMAIN_USER, DOMAIN_MANAGER) |     \
  76                          domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) |   \
  77                          domain_val(DOMAIN_IO, DOMAIN_CLIENT),         \
  78        .restart_block  = {                                             \
  79                .fn     = do_no_restart_syscall,                        \
  80        },                                                              \
  81}
  82
  83#define init_thread_info        (init_thread_union.thread_info)
  84#define init_stack              (init_thread_union.stack)
  85
  86/*
  87 * how to get the thread information struct from C
  88 */
  89static inline struct thread_info *current_thread_info(void) __attribute_const__;
  90
  91static inline struct thread_info *current_thread_info(void)
  92{
  93        register unsigned long sp asm ("sp");
  94        return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
  95}
  96
  97/* thread information allocation */
  98#ifdef CONFIG_DEBUG_STACK_USAGE
  99#define alloc_thread_info(tsk) \
 100        ((struct thread_info *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, \
 101                THREAD_SIZE_ORDER))
 102#else
 103#define alloc_thread_info(tsk) \
 104        ((struct thread_info *)__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER))
 105#endif
 106
 107#define free_thread_info(info) \
 108        free_pages((unsigned long)info, THREAD_SIZE_ORDER);
 109
 110#define thread_saved_pc(tsk)    \
 111        ((unsigned long)(pc_pointer(task_thread_info(tsk)->cpu_context.pc)))
 112#define thread_saved_fp(tsk)    \
 113        ((unsigned long)(task_thread_info(tsk)->cpu_context.fp))
 114
 115extern void crunch_task_disable(struct thread_info *);
 116extern void crunch_task_copy(struct thread_info *, void *);
 117extern void crunch_task_restore(struct thread_info *, void *);
 118extern void crunch_task_release(struct thread_info *);
 119
 120extern void iwmmxt_task_disable(struct thread_info *);
 121extern void iwmmxt_task_copy(struct thread_info *, void *);
 122extern void iwmmxt_task_restore(struct thread_info *, void *);
 123extern void iwmmxt_task_release(struct thread_info *);
 124extern void iwmmxt_task_switch(struct thread_info *);
 125
 126#endif
 127
 128/*
 129 * We use bit 30 of the preempt_count to indicate that kernel
 130 * preemption is occurring.  See include/asm-arm/hardirq.h.
 131 */
 132#define PREEMPT_ACTIVE  0x40000000
 133
 134/*
 135 * thread information flags:
 136 *  TIF_SYSCALL_TRACE   - syscall trace active
 137 *  TIF_SIGPENDING      - signal pending
 138 *  TIF_NEED_RESCHED    - rescheduling necessary
 139 *  TIF_USEDFPU         - FPU was used by this task this quantum (SMP)
 140 *  TIF_POLLING_NRFLAG  - true if poll_idle() is polling TIF_NEED_RESCHED
 141 */
 142#define TIF_SIGPENDING          0
 143#define TIF_NEED_RESCHED        1
 144#define TIF_SYSCALL_TRACE       8
 145#define TIF_POLLING_NRFLAG      16
 146#define TIF_USING_IWMMXT        17
 147#define TIF_MEMDIE              18
 148#define TIF_FREEZE              19
 149
 150#define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 151#define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 152#define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
 153#define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 154#define _TIF_USING_IWMMXT       (1 << TIF_USING_IWMMXT)
 155#define _TIF_FREEZE             (1 << TIF_FREEZE)
 156
 157/*
 158 * Change these and you break ASM code in entry-common.S
 159 */
 160#define _TIF_WORK_MASK          0x000000ff
 161
 162#endif /* __KERNEL__ */
 163#endif /* __ASM_ARM_THREAD_INFO_H */
 164