arch/sh/include/asm/futex.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __ASM_SH_FUTEX_H
   3 #define __ASM_SH_FUTEX_H
   4
   5 #include <linux/futex.h>
   6 #include <linux/uaccess.h>
   7 #include <asm/errno.h>
   8
   9 #if !defined(CONFIG_SMP)
  10 #include <asm/futex-irq.h>
  11 #elif defined(CONFIG_CPU_J2)
  12 #include <asm/futex-cas.h>
  13 #elif defined(CONFIG_CPU_SH4A)
  14 #include <asm/futex-llsc.h>
  15 #else
  16 #error SMP not supported on this configuration.
  17 #endif
  18
  19 static inline int
  20 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  21                               u32 oldval, u32 newval)
  22 {
  23         if (!access_ok(uaddr, sizeof(u32)))
  24                 return -EFAULT;
  25
  26         return atomic_futex_op_cmpxchg_inatomic(uval, uaddr, oldval, newval);
  27 }
  28
  29 static inline int arch_futex_atomic_op_inuser(int op, u32 oparg, int *oval,
  30                 u32 __user *uaddr)
  31 {
  32         u32 oldval, newval, prev;
  33         int ret;
  34
  35         do {
  36                 ret = get_user(oldval, uaddr);
  37
  38                 if (ret) break;
  39
  40                 switch (op) {
  41                 case FUTEX_OP_SET:
  42                         newval = oparg;
  43                         break;
  44                 case FUTEX_OP_ADD:
  45                         newval = oldval + oparg;
  46                         break;
  47                 case FUTEX_OP_OR:
  48                         newval = oldval | oparg;
  49                         break;
  50                 case FUTEX_OP_ANDN:
  51                         newval = oldval & ~oparg;
  52                         break;
  53                 case FUTEX_OP_XOR:
  54                         newval = oldval ^ oparg;
  55                         break;
  56                 default:
  57                         ret = -ENOSYS;
  58                         break;
  59                 }
  60
  61                 if (ret) break;
  62
  63                 ret = futex_atomic_cmpxchg_inatomic(&prev, uaddr, oldval, newval);
  64         } while (!ret && prev != oldval);
  65
  66         if (!ret)
  67                 *oval = oldval;
  68
  69         return ret;
  70 }
  71
  72 #endif /* __ASM_SH_FUTEX_H */