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         struct exec_domain      *exec_domain;   /* execution domain */
  51         unsigned long           flags;          /* low level flags */
  52         __u32                   cpu;            /* current cpu */
  53         int                     preempt_count;  /* 0=>preemptible,<0=>BUG */
  54         mm_segment_t            addr_limit;     /* segmentation sux */
  55         /*
  56          * used for syscalls somehow;
  57          * seems to have a function pointer and four arguments
  58          */
  59         struct restart_block    restart_block;
  60         /* Points to the current pt_regs frame  */
  61         struct pt_regs          *regs;
  62         /*
  63          * saved kernel sp at switch_to time;
  64          * not sure if this is used (it's not in the VM model it seems;
  65          * see thread_struct)
  66          */
  67         unsigned long           sp;
  68 };
  69
  70 #else /* !__ASSEMBLY__ */
  71
  72 #include <asm/asm-offsets.h>
  73
  74 #endif  /* __ASSEMBLY__  */
  75
  76 /*  looks like "linux/hardirq.h" uses this.  */
  77
  78 #define PREEMPT_ACTIVE          0x10000000
  79
  80 #ifndef __ASSEMBLY__
  81
  82 #define INIT_THREAD_INFO(tsk)                   \
  83 {                                               \
  84         .task           = &tsk,                 \
  85         .exec_domain    = &default_exec_domain, \
  86         .flags          = 0,                    \
  87         .cpu            = 0,                    \
  88         .preempt_count  = 1,                    \
  89         .addr_limit     = KERNEL_DS,            \
  90         .restart_block = {                      \
  91                 .fn = do_no_restart_syscall,    \
  92         },                                      \
  93         .sp = 0,                                \
  94         .regs = NULL,                   \
  95 }
  96
  97 #define init_thread_info        (init_thread_union.thread_info)
  98 #define init_stack              (init_thread_union.stack)
  99
 100 /* Tacky preprocessor trickery */
 101 #define qqstr(s) qstr(s)
 102 #define qstr(s) #s
 103 #define QUOTED_THREADINFO_REG qqstr(THREADINFO_REG)
 104
 105 register struct thread_info *__current_thread_info asm(QUOTED_THREADINFO_REG);
 106 #define current_thread_info()  __current_thread_info
 107
 108 #endif /* __ASSEMBLY__ */
 109
 110 /*
 111  * thread information flags
 112  * - these are process state flags that various assembly files
 113  *   may need to access
 114  * - pending work-to-be-done flags are in LSW
 115  * - other flags in MSW
 116  */
 117
 118 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 119 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
 120 #define TIF_SIGPENDING          2       /* signal pending */
 121 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 122 #define TIF_SINGLESTEP          4       /* restore ss @ return to usr mode */
 123 #define TIF_RESTORE_SIGMASK     6       /* restore sig mask in do_signal() */
 124 /* true if poll_idle() is polling TIF_NEED_RESCHED */
 125 #define TIF_MEMDIE              17      /* OOM killer killed process */
 126
 127 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
 128 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
 129 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 130 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 131 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
 132
 133 /* work to do on interrupt/exception return - All but TIF_SYSCALL_TRACE */
 134 #define _TIF_WORK_MASK          (0x0000FFFF & ~_TIF_SYSCALL_TRACE)
 135
 136 /* work to do on any return to u-space */
 137 #define _TIF_ALLWORK_MASK       0x0000FFFF
 138
 139 #endif /* __KERNEL__ */
 140
 141 #endif