arch/mn10300/include/asm/thread_info.h

   1 /* MN10300 Low-level thread information
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public Licence
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the Licence, or (at your option) any later version.
  10  */
  11
  12 #ifndef _ASM_THREAD_INFO_H
  13 #define _ASM_THREAD_INFO_H
  14
  15 #ifdef __KERNEL__
  16
  17 #include <asm/page.h>
  18
  19 #define PREEMPT_ACTIVE          0x10000000
  20
  21 #ifdef CONFIG_4KSTACKS
  22 #define THREAD_SIZE             (4096)
  23 #define THREAD_SIZE_ORDER       (0)
  24 #else
  25 #define THREAD_SIZE             (8192)
  26 #define THREAD_SIZE_ORDER       (1)
  27 #endif
  28
  29 #define STACK_WARN              (THREAD_SIZE / 8)
  30
  31 /*
  32  * low level task data that entry.S needs immediate access to
  33  * - this struct should fit entirely inside of one cache line
  34  * - this struct shares the supervisor stack pages
  35  * - if the contents of this structure are changed, the assembly constants
  36  *   must also be changed
  37  */
  38 #ifndef __ASSEMBLY__
  39 typedef struct {
  40         unsigned long   seg;
  41 } mm_segment_t;
  42
  43 struct thread_info {
  44         struct task_struct      *task;          /* main task structure */
  45         struct exec_domain      *exec_domain;   /* execution domain */
  46         struct pt_regs          *frame;         /* current exception frame */
  47         unsigned long           flags;          /* low level flags */
  48         __u32                   cpu;            /* current CPU */
  49         __s32                   preempt_count;  /* 0 => preemptable, <0 => BUG */
  50
  51         mm_segment_t            addr_limit;     /* thread address space:
  52                                                    0-0xBFFFFFFF for user-thead
  53                                                    0-0xFFFFFFFF for kernel-thread
  54                                                 */
  55         struct restart_block    restart_block;
  56
  57         __u8                    supervisor_stack[0];
  58 };
  59
  60 #define thread_info_to_uregs(ti)                                        \
  61         ((struct pt_regs *)                                             \
  62          ((unsigned long)ti + THREAD_SIZE - sizeof(struct pt_regs)))
  63
  64 #else /* !__ASSEMBLY__ */
  65
  66 #ifndef __ASM_OFFSETS_H__
  67 #include <asm/asm-offsets.h>
  68 #endif
  69
  70 #endif
  71
  72 /*
  73  * macros/functions for gaining access to the thread information structure
  74  */
  75 #ifndef __ASSEMBLY__
  76
  77 #define INIT_THREAD_INFO(tsk)                   \
  78 {                                               \
  79         .task           = &tsk,                 \
  80         .exec_domain    = &default_exec_domain, \
  81         .flags          = 0,                    \
  82         .cpu            = 0,                    \
  83         .preempt_count  = INIT_PREEMPT_COUNT,   \
  84         .addr_limit     = KERNEL_DS,            \
  85         .restart_block = {                      \
  86                 .fn = do_no_restart_syscall,    \
  87         },                                      \
  88 }
  89
  90 #define init_thread_info        (init_thread_union.thread_info)
  91 #define init_stack              (init_thread_union.stack)
  92 #define init_uregs                                                      \
  93         ((struct pt_regs *)                                             \
  94          ((unsigned long) init_stack + THREAD_SIZE - sizeof(struct pt_regs)))
  95
  96 extern struct thread_info *__current_ti;
  97
  98 /* how to get the thread information struct from C */
  99 static inline __attribute__((const))
 100 struct thread_info *current_thread_info(void)
 101 {
 102         struct thread_info *ti;
 103         asm("mov sp,%0\n"
 104             "and %1,%0\n"
 105             : "=d" (ti)
 106             : "i" (~(THREAD_SIZE - 1))
 107             : "cc");
 108         return ti;
 109 }
 110
 111 static inline __attribute__((const))
 112 struct pt_regs *current_frame(void)
 113 {
 114         return current_thread_info()->frame;
 115 }
 116
 117 /* how to get the current stack pointer from C */
 118 static inline unsigned long current_stack_pointer(void)
 119 {
 120         unsigned long sp;
 121         asm("mov sp,%0; ":"=r" (sp));
 122         return sp;
 123 }
 124
 125 #ifndef CONFIG_KGDB
 126 void arch_release_thread_info(struct thread_info *ti);
 127 #endif
 128 #define get_thread_info(ti)     get_task_struct((ti)->task)
 129 #define put_thread_info(ti)     put_task_struct((ti)->task)
 130
 131 #else /* !__ASSEMBLY__ */
 132
 133 #ifndef __VMLINUX_LDS__
 134 /* how to get the thread information struct from ASM */
 135 .macro GET_THREAD_INFO reg
 136         mov     sp,\reg
 137         and     -THREAD_SIZE,\reg
 138 .endm
 139 #endif
 140 #endif
 141
 142 /*
 143  * thread information flags
 144  * - these are process state flags that various assembly files may need to
 145  *   access
 146  * - pending work-to-be-done flags are in LSW
 147  * - other flags in MSW
 148  */
 149 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 150 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 151 #define TIF_SIGPENDING          2       /* signal pending */
 152 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 153 #define TIF_SINGLESTEP          4       /* restore singlestep on return to user mode */
 154 #define TIF_RESTORE_SIGMASK     5       /* restore signal mask in do_signal() */
 155 #define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 156 #define TIF_MEMDIE              17      /* is terminating due to OOM killer */
 157
 158 #define _TIF_SYSCALL_TRACE      +(1 << TIF_SYSCALL_TRACE)
 159 #define _TIF_NOTIFY_RESUME      +(1 << TIF_NOTIFY_RESUME)
 160 #define _TIF_SIGPENDING         +(1 << TIF_SIGPENDING)
 161 #define _TIF_NEED_RESCHED       +(1 << TIF_NEED_RESCHED)
 162 #define _TIF_SINGLESTEP         +(1 << TIF_SINGLESTEP)
 163 #define _TIF_POLLING_NRFLAG     +(1 << TIF_POLLING_NRFLAG)
 164
 165 #define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */
 166 #define _TIF_ALLWORK_MASK       0x0000FFFF      /* work to do on any return to u-space */
 167
 168 #endif /* __KERNEL__ */
 169
 170 #endif /* _ASM_THREAD_INFO_H */