arch/sparc/include/asm/futex_64.h

   1 #ifndef _SPARC64_FUTEX_H
   2 #define _SPARC64_FUTEX_H
   3
   4 #include <linux/futex.h>
   5 #include <linux/uaccess.h>
   6 #include <asm/errno.h>
   7
   8 #define __futex_cas_op(insn, ret, oldval, uaddr, oparg) \
   9         __asm__ __volatile__(                           \
  10         "\n1:   lduwa   [%3] %%asi, %2\n"               \
  11         "       " insn "\n"                             \
  12         "2:     casa    [%3] %%asi, %2, %1\n"           \
  13         "       cmp     %2, %1\n"                       \
  14         "       bne,pn  %%icc, 1b\n"                    \
  15         "        mov    0, %0\n"                        \
  16         "3:\n"                                          \
  17         "       .section .fixup,#alloc,#execinstr\n"    \
  18         "       .align  4\n"                            \
  19         "4:     sethi   %%hi(3b), %0\n"                 \
  20         "       jmpl    %0 + %%lo(3b), %%g0\n"          \
  21         "        mov    %5, %0\n"                       \
  22         "       .previous\n"                            \
  23         "       .section __ex_table,\"a\"\n"            \
  24         "       .align  4\n"                            \
  25         "       .word   1b, 4b\n"                       \
  26         "       .word   2b, 4b\n"                       \
  27         "       .previous\n"                            \
  28         : "=&r" (ret), "=&r" (oldval), "=&r" (tem)      \
  29         : "r" (uaddr), "r" (oparg), "i" (-EFAULT)       \
  30         : "memory")
  31
  32 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
  33                 u32 __user *uaddr)
  34 {
  35         int oldval = 0, ret, tem;
  36
  37         if (unlikely((((unsigned long) uaddr) & 0x3UL)))
  38                 return -EINVAL;
  39
  40         pagefault_disable();
  41
  42         switch (op) {
  43         case FUTEX_OP_SET:
  44                 __futex_cas_op("mov\t%4, %1", ret, oldval, uaddr, oparg);
  45                 break;
  46         case FUTEX_OP_ADD:
  47                 __futex_cas_op("add\t%2, %4, %1", ret, oldval, uaddr, oparg);
  48                 break;
  49         case FUTEX_OP_OR:
  50                 __futex_cas_op("or\t%2, %4, %1", ret, oldval, uaddr, oparg);
  51                 break;
  52         case FUTEX_OP_ANDN:
  53                 __futex_cas_op("andn\t%2, %4, %1", ret, oldval, uaddr, oparg);
  54                 break;
  55         case FUTEX_OP_XOR:
  56                 __futex_cas_op("xor\t%2, %4, %1", ret, oldval, uaddr, oparg);
  57                 break;
  58         default:
  59                 ret = -ENOSYS;
  60         }
  61
  62         pagefault_enable();
  63
  64         if (!ret)
  65                 *oval = oldval;
  66
  67         return ret;
  68 }
  69
  70 static inline int
  71 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  72                               u32 oldval, u32 newval)
  73 {
  74         int ret = 0;
  75
  76         __asm__ __volatile__(
  77         "\n1:   casa    [%4] %%asi, %3, %1\n"
  78         "2:\n"
  79         "       .section .fixup,#alloc,#execinstr\n"
  80         "       .align  4\n"
  81         "3:     sethi   %%hi(2b), %0\n"
  82         "       jmpl    %0 + %%lo(2b), %%g0\n"
  83         "       mov     %5, %0\n"
  84         "       .previous\n"
  85         "       .section __ex_table,\"a\"\n"
  86         "       .align  4\n"
  87         "       .word   1b, 3b\n"
  88         "       .previous\n"
  89         : "+r" (ret), "=r" (newval)
  90         : "1" (newval), "r" (oldval), "r" (uaddr), "i" (-EFAULT)
  91         : "memory");
  92
  93         *uval = newval;
  94         return ret;
  95 }
  96
  97 #endif /* !(_SPARC64_FUTEX_H) */