arch/arm64/include/asm/thread_info.h

   1 /*
   2  * Based on arch/arm/include/asm/thread_info.h
   3  *
   4  * Copyright (C) 2002 Russell King.
   5  * Copyright (C) 2012 ARM Ltd.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #ifndef __ASM_THREAD_INFO_H
  20 #define __ASM_THREAD_INFO_H
  21
  22 #ifdef __KERNEL__
  23
  24 #include <linux/compiler.h>
  25
  26 #ifndef CONFIG_ARM64_64K_PAGES
  27 #define THREAD_SIZE_ORDER       2
  28 #endif
  29
  30 #define THREAD_SIZE             16384
  31 #define THREAD_START_SP         (THREAD_SIZE - 16)
  32
  33 #ifndef __ASSEMBLY__
  34
  35 struct task_struct;
  36 struct exec_domain;
  37
  38 #include <asm/types.h>
  39
  40 typedef unsigned long mm_segment_t;
  41
  42 /*
  43  * low level task data that entry.S needs immediate access to.
  44  * __switch_to() assumes cpu_context follows immediately after cpu_domain.
  45  */
  46 struct thread_info {
  47         unsigned long           flags;          /* low level flags */
  48         mm_segment_t            addr_limit;     /* address limit */
  49         struct task_struct      *task;          /* main task structure */
  50         struct exec_domain      *exec_domain;   /* execution domain */
  51         struct restart_block    restart_block;
  52         int                     preempt_count;  /* 0 => preemptable, <0 => bug */
  53         int                     cpu;            /* cpu */
  54 };
  55
  56 #define INIT_THREAD_INFO(tsk)                                           \
  57 {                                                                       \
  58         .task           = &tsk,                                         \
  59         .exec_domain    = &default_exec_domain,                         \
  60         .flags          = 0,                                            \
  61         .preempt_count  = INIT_PREEMPT_COUNT,                           \
  62         .addr_limit     = KERNEL_DS,                                    \
  63         .restart_block  = {                                             \
  64                 .fn     = do_no_restart_syscall,                        \
  65         },                                                              \
  66 }
  67
  68 #define init_thread_info        (init_thread_union.thread_info)
  69 #define init_stack              (init_thread_union.stack)
  70
  71 /*
  72  * how to get the thread information struct from C
  73  */
  74 static inline struct thread_info *current_thread_info(void) __attribute_const__;
  75
  76 static inline struct thread_info *current_thread_info(void)
  77 {
  78         register unsigned long sp asm ("sp");
  79         return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
  80 }
  81
  82 #define thread_saved_pc(tsk)    \
  83         ((unsigned long)(tsk->thread.cpu_context.pc))
  84 #define thread_saved_sp(tsk)    \
  85         ((unsigned long)(tsk->thread.cpu_context.sp))
  86 #define thread_saved_fp(tsk)    \
  87         ((unsigned long)(tsk->thread.cpu_context.fp))
  88
  89 #endif
  90
  91 /*
  92  * We use bit 30 of the preempt_count to indicate that kernel
  93  * preemption is occurring.  See <asm/hardirq.h>.
  94  */
  95 #define PREEMPT_ACTIVE  0x40000000
  96
  97 /*
  98  * thread information flags:
  99  *  TIF_SYSCALL_TRACE   - syscall trace active
 100  *  TIF_SIGPENDING      - signal pending
 101  *  TIF_NEED_RESCHED    - rescheduling necessary
 102  *  TIF_NOTIFY_RESUME   - callback before returning to user
 103  *  TIF_USEDFPU         - FPU was used by this task this quantum (SMP)
 104  *  TIF_POLLING_NRFLAG  - true if poll_idle() is polling TIF_NEED_RESCHED
 105  */
 106 #define TIF_SIGPENDING          0
 107 #define TIF_NEED_RESCHED        1
 108 #define TIF_NOTIFY_RESUME       2       /* callback before returning to user */
 109 #define TIF_SYSCALL_TRACE       8
 110 #define TIF_POLLING_NRFLAG      16
 111 #define TIF_MEMDIE              18      /* is terminating due to OOM killer */
 112 #define TIF_FREEZE              19
 113 #define TIF_RESTORE_SIGMASK     20
 114 #define TIF_SINGLESTEP          21
 115 #define TIF_32BIT               22      /* 32bit process */
 116 #define TIF_SWITCH_MM           23      /* deferred switch_mm */
 117
 118 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 119 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 120 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
 121 #define _TIF_32BIT              (1 << TIF_32BIT)
 122
 123 #define _TIF_WORK_MASK          (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
 124                                  _TIF_NOTIFY_RESUME)
 125
 126 #endif /* __KERNEL__ */
 127 #endif /* __ASM_THREAD_INFO_H */