LXR linux/arch/sh/include/asm/thread

   1#ifndef __ASM_SH_THREAD_INFO_H
   2#define __ASM_SH_THREAD_INFO_H
   3
   4/* SuperH version
   5 * Copyright (C) 2002  Niibe Yutaka
   6 *
   7 * The copyright of original i386 version is:
   8 *
   9 *  Copyright (C) 2002  David Howells (dhowells@redhat.com)
  10 *  - Incorporating suggestions made by Linus Torvalds and Dave Miller
  11 */
  12#ifdef __KERNEL__
  13
  14#include <asm/page.h>
  15
  16/*
  17 * Page fault error code bits
  18 */
  19#define FAULT_CODE_WRITE        (1 << 0)        /* write access */
  20#define FAULT_CODE_INITIAL      (1 << 1)        /* initial page write */
  21#define FAULT_CODE_ITLB         (1 << 2)        /* ITLB miss */
  22#define FAULT_CODE_PROT         (1 << 3)        /* protection fault */
  23#define FAULT_CODE_USER         (1 << 4)        /* user-mode access */
  24
  25#ifndef __ASSEMBLY__
  26#include <asm/processor.h>
  27
  28struct thread_info {
  29        struct task_struct      *task;          /* main task structure */
  30        struct exec_domain      *exec_domain;   /* execution domain */
  31        unsigned long           flags;          /* low level flags */
  32        __u32                   status;         /* thread synchronous flags */
  33        __u32                   cpu;
  34        int                     preempt_count; /* 0 => preemptable, <0 => BUG */
  35        mm_segment_t            addr_limit;     /* thread address space */
  36        unsigned long           previous_sp;    /* sp of previous stack in case
  37                                                   of nested IRQ stacks */
  38        __u8                    supervisor_stack[0];
  39};
  40
  41#endif
  42
  43#if defined(CONFIG_4KSTACKS)
  44#define THREAD_SHIFT    12
  45#else
  46#define THREAD_SHIFT    13
  47#endif
  48
  49#define THREAD_SIZE     (1 << THREAD_SHIFT)
  50#define STACK_WARN      (THREAD_SIZE >> 3)
  51
  52/*
  53 * macros/functions for gaining access to the thread information structure
  54 */
  55#ifndef __ASSEMBLY__
  56#define INIT_THREAD_INFO(tsk)                   \
  57{                                               \
  58        .task           = &tsk,                 \
  59        .exec_domain    = &default_exec_domain, \
  60        .flags          = 0,                    \
  61        .status         = 0,                    \
  62        .cpu            = 0,                    \
  63        .preempt_count  = INIT_PREEMPT_COUNT,   \
  64        .addr_limit     = KERNEL_DS,            \
  65}
  66
  67#define init_thread_info        (init_thread_union.thread_info)
  68#define init_stack              (init_thread_union.stack)
  69
  70/* how to get the current stack pointer from C */
  71register unsigned long current_stack_pointer asm("r15") __used;
  72
  73/* how to get the thread information struct from C */
  74static inline struct thread_info *current_thread_info(void)
  75{
  76        struct thread_info *ti;
  77#if defined(CONFIG_SUPERH64)
  78        __asm__ __volatile__ ("getcon   cr17, %0" : "=r" (ti));
  79#elif defined(CONFIG_CPU_HAS_SR_RB)
  80        __asm__ __volatile__ ("stc      r7_bank, %0" : "=r" (ti));
  81#else
  82        unsigned long __dummy;
  83
  84        __asm__ __volatile__ (
  85                "mov    r15, %0\n\t"
  86                "and    %1, %0\n\t"
  87                : "=&r" (ti), "=r" (__dummy)
  88                : "1" (~(THREAD_SIZE - 1))
  89                : "memory");
  90#endif
  91
  92        return ti;
  93}
  94
  95#define THREAD_SIZE_ORDER       (THREAD_SHIFT - PAGE_SHIFT)
  96
  97extern void arch_task_cache_init(void);
  98extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
  99extern void arch_release_task_struct(struct task_struct *tsk);
 100extern void init_thread_xstate(void);
 101
 102#endif /* __ASSEMBLY__ */
 103
 104/*
 105 * Thread information flags
 106 *
 107 * - Limited to 24 bits, upper byte used for fault code encoding.
 108 *
 109 * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
 110 *   we blow the tst immediate size constraints and need to fix up
 111 *   arch/sh/kernel/entry-common.S.
 112 */
 113#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 114#define TIF_SIGPENDING          1       /* signal pending */
 115#define TIF_NEED_RESCHED        2       /* rescheduling necessary */
 116#define TIF_SINGLESTEP          4       /* singlestepping active */
 117#define TIF_SYSCALL_AUDIT       5       /* syscall auditing active */
 118#define TIF_SECCOMP             6       /* secure computing */
 119#define TIF_NOTIFY_RESUME       7       /* callback before returning to user */
 120#define TIF_SYSCALL_TRACEPOINT  8       /* for ftrace syscall instrumentation */
 121#define TIF_POLLING_NRFLAG      17      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 122#define TIF_MEMDIE              18      /* is terminating due to OOM killer */
 123
 124#define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
 125#define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
 126#define _TIF_NEED_RESCHED       (1 << TIF_NEED_RESCHED)
 127#define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
 128#define _TIF_SYSCALL_AUDIT      (1 << TIF_SYSCALL_AUDIT)
 129#define _TIF_SECCOMP            (1 << TIF_SECCOMP)
 130#define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
 131#define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT)
 132#define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 133
 134/* work to do in syscall trace */
 135#define _TIF_WORK_SYSCALL_MASK  (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
 136                                 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP    | \
 137                                 _TIF_SYSCALL_TRACEPOINT)
 138
 139/* work to do on any return to u-space */
 140#define _TIF_ALLWORK_MASK       (_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
 141                                 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
 142                                 _TIF_SINGLESTEP    | _TIF_NOTIFY_RESUME   | \
 143                                 _TIF_SYSCALL_TRACEPOINT)
 144
 145/* work to do on interrupt/exception return */
 146#define _TIF_WORK_MASK          (_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
 147                                 _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
 148
 149/*
 150 * Thread-synchronous status.
 151 *
 152 * This is different from the flags in that nobody else
 153 * ever touches our thread-synchronous status, so we don't
 154 * have to worry about atomic accesses.
 155 */
 156#define TS_RESTORE_SIGMASK      0x0001  /* restore signal mask in do_signal() */
 157#define TS_USEDFPU              0x0002  /* FPU used by this task this quantum */
 158
 159#ifndef __ASSEMBLY__
 160
 161#define HAVE_SET_RESTORE_SIGMASK        1
 162static inline void set_restore_sigmask(void)
 163{
 164        struct thread_info *ti = current_thread_info();
 165        ti->status |= TS_RESTORE_SIGMASK;
 166        WARN_ON(!test_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags));
 167}
 168
 169#define TI_FLAG_FAULT_CODE_SHIFT        24
 170
 171/*
 172 * Additional thread flag encoding
 173 */
 174static inline void set_thread_fault_code(unsigned int val)
 175{
 176        struct thread_info *ti = current_thread_info();
 177        ti->flags = (ti->flags & (~0 >> (32 - TI_FLAG_FAULT_CODE_SHIFT)))
 178                | (val << TI_FLAG_FAULT_CODE_SHIFT);
 179}
 180
 181static inline unsigned int get_thread_fault_code(void)
 182{
 183        struct thread_info *ti = current_thread_info();
 184        return ti->flags >> TI_FLAG_FAULT_CODE_SHIFT;
 185}
 186
 187static inline void clear_restore_sigmask(void)
 188{
 189        current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
 190}
 191static inline bool test_restore_sigmask(void)
 192{
 193        return current_thread_info()->status & TS_RESTORE_SIGMASK;
 194}
 195static inline bool test_and_clear_restore_sigmask(void)
 196{
 197        struct thread_info *ti = current_thread_info();
 198        if (!(ti->status & TS_RESTORE_SIGMASK))
 199                return false;
 200        ti->status &= ~TS_RESTORE_SIGMASK;
 201        return true;
 202}
 203
 204#endif  /* !__ASSEMBLY__ */
 205
 206#endif /* __KERNEL__ */
 207
 208#endif /* __ASM_SH_THREAD_INFO_H */
 209