LXR linux/arch/sparc/include/asm/futex

   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
  33static 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
  71static inline int
  72futex_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) */
  99