root/arch/sparc/include/asm/futex_64.h

INCLUDED FROM

DEFINITIONS

1. arch_futex_atomic_op_inuser
2. futex_atomic_cmpxchg_inatomic

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _SPARC64_FUTEX_H
   3 #define _SPARC64_FUTEX_H
   4 
   5 #include <linux/futex.h>
   6 #include <linux/uaccess.h>
   7 #include <asm/errno.h>
   8 
   9 #define __futex_cas_op(insn, ret, oldval, uaddr, oparg) \
  10         __asm__ __volatile__(                           \
  11         "\n1:   lduwa   [%3] %%asi, %2\n"               \
  12         "       " insn "\n"                             \
  13         "2:     casa    [%3] %%asi, %2, %1\n"           \
  14         "       cmp     %2, %1\n"                       \
  15         "       bne,pn  %%icc, 1b\n"                    \
  16         "        mov    0, %0\n"                        \
  17         "3:\n"                                          \
  18         "       .section .fixup,#alloc,#execinstr\n"    \
  19         "       .align  4\n"                            \
  20         "4:     sethi   %%hi(3b), %0\n"                 \
  21         "       jmpl    %0 + %%lo(3b), %%g0\n"          \
  22         "        mov    %5, %0\n"                       \
  23         "       .previous\n"                            \
  24         "       .section __ex_table,\"a\"\n"            \
  25         "       .align  4\n"                            \
  26         "       .word   1b, 4b\n"                       \
  27         "       .word   2b, 4b\n"                       \
  28         "       .previous\n"                            \
  29         : "=&r" (ret), "=&r" (oldval), "=&r" (tem)      \
  30         : "r" (uaddr), "r" (oparg), "i" (-EFAULT)       \
  31         : "memory")
  32 
  33 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
  34                 u32 __user *uaddr)
  35 {
  36         int oldval = 0, ret, tem;
  37 
  38         if (unlikely((((unsigned long) uaddr) & 0x3UL)))
  39                 return -EINVAL;
  40 
  41         pagefault_disable();
  42 
  43         switch (op) {
  44         case FUTEX_OP_SET:
  45                 __futex_cas_op("mov\t%4, %1", ret, oldval, uaddr, oparg);
  46                 break;
  47         case FUTEX_OP_ADD:
  48                 __futex_cas_op("add\t%2, %4, %1", ret, oldval, uaddr, oparg);
  49                 break;
  50         case FUTEX_OP_OR:
  51                 __futex_cas_op("or\t%2, %4, %1", ret, oldval, uaddr, oparg);
  52                 break;
  53         case FUTEX_OP_ANDN:
  54                 __futex_cas_op("andn\t%2, %4, %1", ret, oldval, uaddr, oparg);
  55                 break;
  56         case FUTEX_OP_XOR:
  57                 __futex_cas_op("xor\t%2, %4, %1", ret, oldval, uaddr, oparg);
  58                 break;
  59         default:
  60                 ret = -ENOSYS;
  61         }
  62 
  63         pagefault_enable();
  64 
  65         if (!ret)
  66                 *oval = oldval;
  67 
  68         return ret;
  69 }
  70 
  71 static inline int
  72 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  73                               u32 oldval, u32 newval)
  74 {
  75         int ret = 0;
  76 
  77         __asm__ __volatile__(
  78         "\n1:   casa    [%4] %%asi, %3, %1\n"
  79         "2:\n"
  80         "       .section .fixup,#alloc,#execinstr\n"
  81         "       .align  4\n"
  82         "3:     sethi   %%hi(2b), %0\n"
  83         "       jmpl    %0 + %%lo(2b), %%g0\n"
  84         "       mov     %5, %0\n"
  85         "       .previous\n"
  86         "       .section __ex_table,\"a\"\n"
  87         "       .align  4\n"
  88         "       .word   1b, 3b\n"
  89         "       .previous\n"
  90         : "+r" (ret), "=r" (newval)
  91         : "1" (newval), "r" (oldval), "r" (uaddr), "i" (-EFAULT)
  92         : "memory");
  93 
  94         *uval = newval;
  95         return ret;
  96 }
  97 
  98 #endif /* !(_SPARC64_FUTEX_H) */