arch/microblaze/include/asm/futex.h

   1 #ifndef _ASM_MICROBLAZE_FUTEX_H
   2 #define _ASM_MICROBLAZE_FUTEX_H
   3
   4 #ifdef __KERNEL__
   5
   6 #include <linux/futex.h>
   7 #include <linux/uaccess.h>
   8 #include <asm/errno.h>
   9
  10 #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
  11 ({                                                                      \
  12         __asm__ __volatile__ (                                          \
  13                         "1:     lwx     %0, %2, r0; "                   \
  14                                 insn                                    \
  15                         "2:     swx     %1, %2, r0;                     \
  16                                 addic   %1, r0, 0;                      \
  17                                 bnei    %1, 1b;                         \
  18                         3:                                              \
  19                         .section .fixup,\"ax\";                         \
  20                         4:      brid    3b;                             \
  21                                 addik   %1, r0, %3;                     \
  22                         .previous;                                      \
  23                         .section __ex_table,\"a\";                      \
  24                         .word   1b,4b,2b,4b;                            \
  25                         .previous;"                                     \
  26         : "=&r" (oldval), "=&r" (ret)                                   \
  27         : "r" (uaddr), "i" (-EFAULT), "r" (oparg)                       \
  28         );                                                              \
  29 })
  30
  31 static inline int
  32 arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
  33 {
  34         int oldval = 0, ret;
  35
  36         pagefault_disable();
  37
  38         switch (op) {
  39         case FUTEX_OP_SET:
  40                 __futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg);
  41                 break;
  42         case FUTEX_OP_ADD:
  43                 __futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg);
  44                 break;
  45         case FUTEX_OP_OR:
  46                 __futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg);
  47                 break;
  48         case FUTEX_OP_ANDN:
  49                 __futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg);
  50                 break;
  51         case FUTEX_OP_XOR:
  52                 __futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg);
  53                 break;
  54         default:
  55                 ret = -ENOSYS;
  56         }
  57
  58         pagefault_enable();
  59
  60         if (!ret)
  61                 *oval = oldval;
  62
  63         return ret;
  64 }
  65
  66 static inline int
  67 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  68                               u32 oldval, u32 newval)
  69 {
  70         int ret = 0, cmp;
  71         u32 prev;
  72
  73         if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
  74                 return -EFAULT;
  75
  76         __asm__ __volatile__ ("1:       lwx     %1, %3, r0;             \
  77                                         cmp     %2, %1, %4;             \
  78                                         bnei    %2, 3f;                 \
  79                                 2:      swx     %5, %3, r0;             \
  80                                         addic   %2, r0, 0;              \
  81                                         bnei    %2, 1b;                 \
  82                                 3:                                      \
  83                                 .section .fixup,\"ax\";                 \
  84                                 4:      brid    3b;                     \
  85                                         addik   %0, r0, %6;             \
  86                                 .previous;                              \
  87                                 .section __ex_table,\"a\";              \
  88                                 .word   1b,4b,2b,4b;                    \
  89                                 .previous;"                             \
  90                 : "+r" (ret), "=&r" (prev), "=&r"(cmp)  \
  91                 : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT));
  92
  93         *uval = prev;
  94         return ret;
  95 }
  96
  97 #endif /* __KERNEL__ */
  98
  99 #endif