arch/hexagon/include/asm/thread_info.h

   1 /*
   2  * Thread support for the Hexagon architecture
   3  *
   4  * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 and
   8  * only version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA.
  19  */
  20
  21 #ifndef _ASM_THREAD_INFO_H
  22 #define _ASM_THREAD_INFO_H
  23
  24 #ifdef __KERNEL__
  25
  26 #ifndef __ASSEMBLY__
  27 #include <asm/processor.h>
  28 #include <asm/registers.h>
  29 #include <asm/page.h>
  30 #endif
  31
  32 #define THREAD_SHIFT            12
  33 #define THREAD_SIZE             (1<<THREAD_SHIFT)
  34 #define THREAD_SIZE_ORDER       (THREAD_SHIFT - PAGE_SHIFT)
  35
  36 #ifndef __ASSEMBLY__
  37
  38 typedef struct {
  39         unsigned long seg;
  40 } mm_segment_t;
  41
  42 /*
  43  * This is union'd with the "bottom" of the kernel stack.
  44  * It keeps track of thread info which is handy for routines
  45  * to access quickly.
  46  */
  47
  48 struct thread_info {
  49         struct task_struct      *task;          /* main task structure */
  50         unsigned long           flags;          /* low level flags */
  51         __u32                   cpu;            /* current cpu */
  52         int                     preempt_count;  /* 0=>preemptible,<0=>BUG */
  53         mm_segment_t            addr_limit;     /* segmentation sux */
  54         /*
  55          * used for syscalls somehow;
  56          * seems to have a function pointer and four arguments
  57          */
  58         /* Points to the current pt_regs frame  */
  59         struct pt_regs          *regs;
  60         /*
  61          * saved kernel sp at switch_to time;
  62          * not sure if this is used (it's not in the VM model it seems;
  63          * see thread_struct)
  64          */
  65         unsigned long           sp;
  66 };
  67
  68 #else /* !__ASSEMBLY__ */
  69
  70 #include <asm/asm-offsets.h>
  71
  72 #endif  /* __ASSEMBLY__  */
  73
  74 #ifndef __ASSEMBLY__
  75
  76 #define INIT_THREAD_INFO(tsk)                   \
  77 {                                               \
  78         .task           = &tsk,                 \
  79         .flags          = 0,                    \
  80         .cpu            = 0,                    \
  81         .preempt_count  = 1,                    \
  82         .addr_limit     = KERNEL_DS,            \
  83         .sp = 0,                                \
  84         .regs = NULL,                   \
  85 }
  86
  87 /* Tacky preprocessor trickery */
  88 #define qqstr(s) qstr(s)
  89 #define qstr(s) #s
  90 #define QUOTED_THREADINFO_REG qqstr(THREADINFO_REG)
  91
  92 register struct thread_info *__current_thread_info asm(QUOTED_THREADINFO_REG);
  93 #define current_thread_info()  __current_thread_info
  94
  95 #endif /* __ASSEMBLY__ */
  96
  97 /*
  98  * thread information flags
  99  * - these are process state flags that various assembly files
 100  *   may need to access
 101  * - pending work-to-be-done flags are in LSW
 102  * - other flags in MSW
 103  */
 104
 105 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 106 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 107 #define TIF_SIGPENDING          2       /* signal pending */
 108 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 109 #define TIF_SINGLESTEP          4       /* restore ss @ return to usr mode */
 110 #define TIF_RESTORE_SIGMASK     6       /* restore sig mask in do_signal() */
 111 /* true if poll_idle() is polling TIF_NEED_RESCHED */
 112 #define TIF_MEMDIE              17      /* OOM killer killed process */
 113
 114 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
 115 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
 116 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 117 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 118 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
 119
 120 /* work to do on interrupt/exception return - All but TIF_SYSCALL_TRACE */
 121 #define _TIF_WORK_MASK          (0x0000FFFF & ~_TIF_SYSCALL_TRACE)
 122
 123 /* work to do on any return to u-space */
 124 #define _TIF_ALLWORK_MASK       0x0000FFFF
 125
 126 #endif /* __KERNEL__ */
 127
 128 #endif