arch/sh/include/asm/thread_info.h

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