arch/xtensa/include/asm/thread_info.h

   1 /*
   2  * include/asm-xtensa/thread_info.h
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  *
   8  * Copyright (C) 2001 - 2005 Tensilica Inc.
   9  */
  10
  11 #ifndef _XTENSA_THREAD_INFO_H
  12 #define _XTENSA_THREAD_INFO_H
  13
  14 #include <linux/stringify.h>
  15 #include <asm/kmem_layout.h>
  16
  17 #define CURRENT_SHIFT KERNEL_STACK_SHIFT
  18
  19 #ifndef __ASSEMBLY__
  20 # include <asm/processor.h>
  21 #endif
  22
  23 /*
  24  * low level task data that entry.S needs immediate access to
  25  * - this struct should fit entirely inside of one cache line
  26  * - this struct shares the supervisor stack pages
  27  * - if the contents of this structure are changed, the assembly constants
  28  *   must also be changed
  29  */
  30
  31 #ifndef __ASSEMBLY__
  32
  33 #if XTENSA_HAVE_COPROCESSORS
  34
  35 typedef struct xtregs_coprocessor {
  36         xtregs_cp0_t cp0;
  37         xtregs_cp1_t cp1;
  38         xtregs_cp2_t cp2;
  39         xtregs_cp3_t cp3;
  40         xtregs_cp4_t cp4;
  41         xtregs_cp5_t cp5;
  42         xtregs_cp6_t cp6;
  43         xtregs_cp7_t cp7;
  44 } xtregs_coprocessor_t;
  45
  46 #endif
  47
  48 struct thread_info {
  49         struct task_struct      *task;          /* main task structure */
  50         unsigned long           flags;          /* low level flags */
  51         unsigned long           status;         /* thread-synchronous flags */
  52         __u32                   cpu;            /* current CPU */
  53         __s32                   preempt_count;  /* 0 => preemptable,< 0 => BUG*/
  54
  55         mm_segment_t            addr_limit;     /* thread address space */
  56
  57         unsigned long           cpenable;
  58
  59         /* Allocate storage for extra user states and coprocessor states. */
  60 #if XTENSA_HAVE_COPROCESSORS
  61         xtregs_coprocessor_t    xtregs_cp;
  62 #endif
  63         xtregs_user_t           xtregs_user;
  64 };
  65
  66 #endif
  67
  68 /*
  69  * macros/functions for gaining access to the thread information structure
  70  */
  71
  72 #ifndef __ASSEMBLY__
  73
  74 #define INIT_THREAD_INFO(tsk)                   \
  75 {                                               \
  76         .task           = &tsk,                 \
  77         .flags          = 0,                    \
  78         .cpu            = 0,                    \
  79         .preempt_count  = INIT_PREEMPT_COUNT,   \
  80         .addr_limit     = KERNEL_DS,            \
  81 }
  82
  83 /* how to get the thread information struct from C */
  84 static inline struct thread_info *current_thread_info(void)
  85 {
  86         struct thread_info *ti;
  87          __asm__("extui %0, a1, 0, "__stringify(CURRENT_SHIFT)"\n\t"
  88                  "xor %0, a1, %0" : "=&r" (ti) : );
  89         return ti;
  90 }
  91
  92 #else /* !__ASSEMBLY__ */
  93
  94 /* how to get the thread information struct from ASM */
  95 #define GET_THREAD_INFO(reg,sp) \
  96         extui reg, sp, 0, CURRENT_SHIFT; \
  97         xor   reg, sp, reg
  98 #endif
  99
 100
 101 /*
 102  * thread information flags
 103  * - these are process state flags that various assembly files may need to access
 104  */
 105 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 106 #define TIF_SIGPENDING          1       /* signal pending */
 107 #define TIF_NEED_RESCHED        2       /* rescheduling necessary */
 108 #define TIF_SINGLESTEP          3       /* restore singlestep on return to user mode */
 109 #define TIF_SYSCALL_TRACEPOINT  4       /* syscall tracepoint instrumentation */
 110 #define TIF_MEMDIE              5       /* is terminating due to OOM killer */
 111 #define TIF_RESTORE_SIGMASK     6       /* restore signal mask in do_signal() */
 112 #define TIF_NOTIFY_RESUME       7       /* callback before returning to user */
 113 #define TIF_DB_DISABLED         8       /* debug trap disabled for syscall */
 114
 115 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 116 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 117 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 118 #define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 119 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
 120
 121 #define _TIF_WORK_MASK          (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
 122                                  _TIF_SYSCALL_TRACEPOINT)
 123
 124 #define THREAD_SIZE KERNEL_STACK_SIZE
 125 #define THREAD_SIZE_ORDER (KERNEL_STACK_SHIFT - PAGE_SHIFT)
 126
 127 #endif  /* _XTENSA_THREAD_INFO */