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 #ifndef __ASSEMBLY__
  20 #include <asm/processor.h>
  21 #endif
  22
  23 #define PREEMPT_ACTIVE          0x10000000
  24
  25 #ifdef CONFIG_4KSTACKS
  26 #define THREAD_SIZE             (4096)
  27 #else
  28 #define THREAD_SIZE             (8192)
  29 #endif
  30
  31 #define STACK_WARN              (THREAD_SIZE / 8)
  32
  33 /*
  34  * low level task data that entry.S needs immediate access to
  35  * - this struct should fit entirely inside of one cache line
  36  * - this struct shares the supervisor stack pages
  37  * - if the contents of this structure are changed, the assembly constants
  38  *   must also be changed
  39  */
  40 #ifndef __ASSEMBLY__
  41
  42 struct thread_info {
  43         struct task_struct      *task;          /* main task structure */
  44         struct exec_domain      *exec_domain;   /* execution domain */
  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 #else /* !__ASSEMBLY__ */
  59
  60 #ifndef __ASM_OFFSETS_H__
  61 #include <asm/asm-offsets.h>
  62 #endif
  63
  64 #endif
  65
  66 /*
  67  * macros/functions for gaining access to the thread information structure
  68  */
  69 #ifndef __ASSEMBLY__
  70
  71 #define INIT_THREAD_INFO(tsk)                   \
  72 {                                               \
  73         .task           = &tsk,                 \
  74         .exec_domain    = &default_exec_domain, \
  75         .flags          = 0,                    \
  76         .cpu            = 0,                    \
  77         .preempt_count  = INIT_PREEMPT_COUNT,   \
  78         .addr_limit     = KERNEL_DS,            \
  79         .restart_block = {                      \
  80                 .fn = do_no_restart_syscall,    \
  81         },                                      \
  82 }
  83
  84 #define init_thread_info        (init_thread_union.thread_info)
  85 #define init_stack              (init_thread_union.stack)
  86 #define init_uregs                                                      \
  87         ((struct pt_regs *)                                             \
  88          ((unsigned long) init_stack + THREAD_SIZE - sizeof(struct pt_regs)))
  89
  90 extern struct thread_info *__current_ti;
  91
  92 /* how to get the thread information struct from C */
  93 static inline __attribute__((const))
  94 struct thread_info *current_thread_info(void)
  95 {
  96         struct thread_info *ti;
  97         asm("mov sp,%0\n"
  98             "and %1,%0\n"
  99             : "=d" (ti)
 100             : "i" (~(THREAD_SIZE - 1))
 101             : "cc");
 102         return ti;
 103 }
 104
 105 /* how to get the current stack pointer from C */
 106 static inline unsigned long current_stack_pointer(void)
 107 {
 108         unsigned long sp;
 109         asm("mov sp,%0; ":"=r" (sp));
 110         return sp;
 111 }
 112
 113 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
 114
 115 /* thread information allocation */
 116 #ifdef CONFIG_DEBUG_STACK_USAGE
 117 #define alloc_thread_info(tsk) kzalloc(THREAD_SIZE, GFP_KERNEL)
 118 #else
 119 #define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
 120 #endif
 121
 122 #define free_thread_info(ti)    kfree((ti))
 123 #define get_thread_info(ti)     get_task_struct((ti)->task)
 124 #define put_thread_info(ti)     put_task_struct((ti)->task)
 125
 126 #else /* !__ASSEMBLY__ */
 127
 128 #ifndef __VMLINUX_LDS__
 129 /* how to get the thread information struct from ASM */
 130 .macro GET_THREAD_INFO reg
 131         mov     sp,\reg
 132         and     -THREAD_SIZE,\reg
 133 .endm
 134 #endif
 135 #endif
 136
 137 /*
 138  * thread information flags
 139  * - these are process state flags that various assembly files may need to
 140  *   access
 141  * - pending work-to-be-done flags are in LSW
 142  * - other flags in MSW
 143  */
 144 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 145 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 146 #define TIF_SIGPENDING          2       /* signal pending */
 147 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 148 #define TIF_SINGLESTEP          4       /* restore singlestep on return to user mode */
 149 #define TIF_RESTORE_SIGMASK     5       /* restore signal mask in do_signal() */
 150 #define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 151 #define TIF_MEMDIE              17      /* OOM killer killed process */
 152 #define TIF_FREEZE              18      /* freezing for suspend */
 153
 154 #define _TIF_SYSCALL_TRACE      +(1 << TIF_SYSCALL_TRACE)
 155 #define _TIF_NOTIFY_RESUME      +(1 << TIF_NOTIFY_RESUME)
 156 #define _TIF_SIGPENDING         +(1 << TIF_SIGPENDING)
 157 #define _TIF_NEED_RESCHED       +(1 << TIF_NEED_RESCHED)
 158 #define _TIF_SINGLESTEP         +(1 << TIF_SINGLESTEP)
 159 #define _TIF_RESTORE_SIGMASK    +(1 << TIF_RESTORE_SIGMASK)
 160 #define _TIF_POLLING_NRFLAG     +(1 << TIF_POLLING_NRFLAG)
 161 #define _TIF_FREEZE             +(1 << TIF_FREEZE)
 162
 163 #define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */
 164 #define _TIF_ALLWORK_MASK       0x0000FFFF      /* work to do on any return to u-space */
 165
 166 #endif /* __KERNEL__ */
 167
 168 #endif /* _ASM_THREAD_INFO_H */