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 #else
  24 #define THREAD_SIZE             (8192)
  25 #endif
  26
  27 #define STACK_WARN              (THREAD_SIZE / 8)
  28
  29 /*
  30  * low level task data that entry.S needs immediate access to
  31  * - this struct should fit entirely inside of one cache line
  32  * - this struct shares the supervisor stack pages
  33  * - if the contents of this structure are changed, the assembly constants
  34  *   must also be changed
  35  */
  36 #ifndef __ASSEMBLY__
  37 typedef struct {
  38         unsigned long   seg;
  39 } mm_segment_t;
  40
  41 struct thread_info {
  42         struct task_struct      *task;          /* main task structure */
  43         struct exec_domain      *exec_domain;   /* execution domain */
  44         struct pt_regs          *frame;         /* current exception frame */
  45         unsigned long           flags;          /* low level flags */
  46         __u32                   cpu;            /* current CPU */
  47         __s32                   preempt_count;  /* 0 => preemptable, <0 => BUG */
  48
  49         mm_segment_t            addr_limit;     /* thread address space:
  50                                                    0-0xBFFFFFFF for user-thead
  51                                                    0-0xFFFFFFFF for kernel-thread
  52                                                 */
  53         struct restart_block    restart_block;
  54
  55         __u8                    supervisor_stack[0];
  56 };
  57
  58 #define thread_info_to_uregs(ti)                                        \
  59         ((struct pt_regs *)                                             \
  60          ((unsigned long)ti + THREAD_SIZE - sizeof(struct pt_regs)))
  61
  62 #else /* !__ASSEMBLY__ */
  63
  64 #ifndef __ASM_OFFSETS_H__
  65 #include <asm/asm-offsets.h>
  66 #endif
  67
  68 #endif
  69
  70 /*
  71  * macros/functions for gaining access to the thread information structure
  72  */
  73 #ifndef __ASSEMBLY__
  74
  75 #define INIT_THREAD_INFO(tsk)                   \
  76 {                                               \
  77         .task           = &tsk,                 \
  78         .exec_domain    = &default_exec_domain, \
  79         .flags          = 0,                    \
  80         .cpu            = 0,                    \
  81         .preempt_count  = INIT_PREEMPT_COUNT,   \
  82         .addr_limit     = KERNEL_DS,            \
  83         .restart_block = {                      \
  84                 .fn = do_no_restart_syscall,    \
  85         },                                      \
  86 }
  87
  88 #define init_thread_info        (init_thread_union.thread_info)
  89 #define init_stack              (init_thread_union.stack)
  90 #define init_uregs                                                      \
  91         ((struct pt_regs *)                                             \
  92          ((unsigned long) init_stack + THREAD_SIZE - sizeof(struct pt_regs)))
  93
  94 extern struct thread_info *__current_ti;
  95
  96 /* how to get the thread information struct from C */
  97 static inline __attribute__((const))
  98 struct thread_info *current_thread_info(void)
  99 {
 100         struct thread_info *ti;
 101         asm("mov sp,%0\n"
 102             "and %1,%0\n"
 103             : "=d" (ti)
 104             : "i" (~(THREAD_SIZE - 1))
 105             : "cc");
 106         return ti;
 107 }
 108
 109 static inline __attribute__((const))
 110 struct pt_regs *current_frame(void)
 111 {
 112         return current_thread_info()->frame;
 113 }
 114
 115 /* how to get the current stack pointer from C */
 116 static inline unsigned long current_stack_pointer(void)
 117 {
 118         unsigned long sp;
 119         asm("mov sp,%0; ":"=r" (sp));
 120         return sp;
 121 }
 122
 123 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
 124
 125 /* thread information allocation */
 126 #ifdef CONFIG_DEBUG_STACK_USAGE
 127 #define alloc_thread_info_node(tsk, node)                       \
 128                 kzalloc_node(THREAD_SIZE, GFP_KERNEL, node)
 129 #else
 130 #define alloc_thread_info_node(tsk, node)                       \
 131                 kmalloc_node(THREAD_SIZE, GFP_KERNEL, node)
 132 #endif
 133
 134 #define free_thread_info(ti)    kfree((ti))
 135 #define get_thread_info(ti)     get_task_struct((ti)->task)
 136 #define put_thread_info(ti)     put_task_struct((ti)->task)
 137
 138 #else /* !__ASSEMBLY__ */
 139
 140 #ifndef __VMLINUX_LDS__
 141 /* how to get the thread information struct from ASM */
 142 .macro GET_THREAD_INFO reg
 143         mov     sp,\reg
 144         and     -THREAD_SIZE,\reg
 145 .endm
 146 #endif
 147 #endif
 148
 149 /*
 150  * thread information flags
 151  * - these are process state flags that various assembly files may need to
 152  *   access
 153  * - pending work-to-be-done flags are in LSW
 154  * - other flags in MSW
 155  */
 156 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 157 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 158 #define TIF_SIGPENDING          2       /* signal pending */
 159 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 160 #define TIF_SINGLESTEP          4       /* restore singlestep on return to user mode */
 161 #define TIF_RESTORE_SIGMASK     5       /* restore signal mask in do_signal() */
 162 #define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 163 #define TIF_MEMDIE              17      /* is terminating due to OOM killer */
 164 #define TIF_FREEZE              18      /* freezing for suspend */
 165
 166 #define _TIF_SYSCALL_TRACE      +(1 << TIF_SYSCALL_TRACE)
 167 #define _TIF_NOTIFY_RESUME      +(1 << TIF_NOTIFY_RESUME)
 168 #define _TIF_SIGPENDING         +(1 << TIF_SIGPENDING)
 169 #define _TIF_NEED_RESCHED       +(1 << TIF_NEED_RESCHED)
 170 #define _TIF_SINGLESTEP         +(1 << TIF_SINGLESTEP)
 171 #define _TIF_RESTORE_SIGMASK    +(1 << TIF_RESTORE_SIGMASK)
 172 #define _TIF_POLLING_NRFLAG     +(1 << TIF_POLLING_NRFLAG)
 173 #define _TIF_FREEZE             +(1 << TIF_FREEZE)
 174
 175 #define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */
 176 #define _TIF_ALLWORK_MASK       0x0000FFFF      /* work to do on any return to u-space */
 177
 178 #endif /* __KERNEL__ */
 179
 180 #endif /* _ASM_THREAD_INFO_H */