arch/nios2/include/asm/thread_info.h

   1 /*
   2  * NiosII low-level thread information
   3  *
   4  * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
   5  * Copyright (C) 2004 Microtronix Datacom Ltd.
   6  *
   7  * Based on asm/thread_info_no.h from m68k which is:
   8  *
   9  * Copyright (C) 2002 David Howells <dhowells@redhat.com>
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License.  See the file "COPYING" in the main directory of this archive
  13  * for more details.
  14  */
  15
  16 #ifndef _ASM_NIOS2_THREAD_INFO_H
  17 #define _ASM_NIOS2_THREAD_INFO_H
  18
  19 #ifdef __KERNEL__
  20
  21 /*
  22  * Size of the kernel stack for each process.
  23  */
  24 #define THREAD_SIZE_ORDER       1
  25 #define THREAD_SIZE             8192 /* 2 * PAGE_SIZE */
  26
  27 #ifndef __ASSEMBLY__
  28
  29 typedef struct {
  30         unsigned long seg;
  31 } mm_segment_t;
  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 struct thread_info {
  41         struct task_struct      *task;          /* main task structure */
  42         unsigned long           flags;          /* low level flags */
  43         __u32                   cpu;            /* current CPU */
  44         int                     preempt_count;  /* 0 => preemptable,<0 => BUG */
  45         mm_segment_t            addr_limit;     /* thread address space:
  46                                                   0-0x7FFFFFFF for user-thead
  47                                                   0-0xFFFFFFFF for kernel-thread
  48                                                 */
  49         struct pt_regs          *regs;
  50 };
  51
  52 /*
  53  * macros/functions for gaining access to the thread information structure
  54  *
  55  * preempt_count needs to be 1 initially, until the scheduler is functional.
  56  */
  57 #define INIT_THREAD_INFO(tsk)                   \
  58 {                                               \
  59         .task           = &tsk,                 \
  60         .flags          = 0,                    \
  61         .cpu            = 0,                    \
  62         .preempt_count  = INIT_PREEMPT_COUNT,   \
  63         .addr_limit     = KERNEL_DS,            \
  64 }
  65
  66 #define init_thread_info        (init_thread_union.thread_info)
  67 #define init_stack              (init_thread_union.stack)
  68
  69 /* how to get the thread information struct from C */
  70 static inline struct thread_info *current_thread_info(void)
  71 {
  72         register unsigned long sp asm("sp");
  73
  74         return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
  75 }
  76 #endif /* !__ASSEMBLY__ */
  77
  78 /*
  79  * thread information flags
  80  * - these are process state flags that various assembly files may need to
  81  *   access
  82  * - pending work-to-be-done flags are in LSW
  83  * - other flags in MSW
  84  */
  85 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
  86 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
  87 #define TIF_SIGPENDING          2       /* signal pending */
  88 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
  89 #define TIF_MEMDIE              4       /* is terminating due to OOM killer */
  90 #define TIF_SECCOMP             5       /* secure computing */
  91 #define TIF_SYSCALL_AUDIT       6       /* syscall auditing active */
  92 #define TIF_RESTORE_SIGMASK     9       /* restore signal mask in do_signal() */
  93
  94 #define TIF_POLLING_NRFLAG      16      /* true if poll_idle() is polling
  95                                            TIF_NEED_RESCHED */
  96
  97 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
  98 #define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
  99 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 100 #define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 101 #define _TIF_SECCOMP            (1 << TIF_SECCOMP)
 102 #define _TIF_SYSCALL_AUDIT      (1 << TIF_SYSCALL_AUDIT)
 103 #define _TIF_RESTORE_SIGMASK    (1 << TIF_RESTORE_SIGMASK)
 104 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 105
 106 /* work to do on interrupt/exception return */
 107 #define _TIF_WORK_MASK          0x0000FFFE
 108
 109 /* work to do on any return to u-space */
 110 # define _TIF_ALLWORK_MASK      0x0000FFFF
 111
 112 #endif /* __KERNEL__ */
 113
 114 #endif /* _ASM_NIOS2_THREAD_INFO_H */