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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_S390_FUTEX_H
#define _ASM_S390_FUTEX_H
#include <linux/uaccess.h>
#include <linux/futex.h>
#include <asm/mmu_context.h>
#include <asm/errno.h>
#define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \
asm volatile( \
" sacf 256\n" \
"0: l %1,0(%6)\n" \
"1:"insn \
"2: cs %1,%2,0(%6)\n" \
"3: jl 1b\n" \
" lhi %0,0\n" \
"4: sacf 768\n" \
EX_TABLE(0b,4b) EX_TABLE(2b,4b) EX_TABLE(3b,4b) \
: "=d" (ret), "=&d" (oldval), "=&d" (newval), \
"=m" (*uaddr) \
: "0" (-EFAULT), "d" (oparg), "a" (uaddr), \
"m" (*uaddr) : "cc");
static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval,
u32 __user *uaddr)
{
int oldval = 0, newval, ret;
mm_segment_t old_fs;
if (!access_ok(uaddr, sizeof(u32)))
return -EFAULT;
old_fs = enable_sacf_uaccess();
switch (op) {
case FUTEX_OP_SET:
__futex_atomic_op("lr %2,%5\n",
ret, oldval, newval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("lr %2,%1\nar %2,%5\n",
ret, oldval, newval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("lr %2,%1\nor %2,%5\n",
ret, oldval, newval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("lr %2,%1\nnr %2,%5\n",
ret, oldval, newval, uaddr, oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("lr %2,%1\nxr %2,%5\n",
ret, oldval, newval, uaddr, oparg);
break;
default:
ret = -ENOSYS;
}
disable_sacf_uaccess(old_fs);
if (!ret)
*oval = oldval;
return ret;
}
static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
u32 oldval, u32 newval)
{
mm_segment_t old_fs;
int ret;
old_fs = enable_sacf_uaccess();
asm volatile(
" sacf 256\n"
"0: cs %1,%4,0(%5)\n"
"1: la %0,0\n"
"2: sacf 768\n"
EX_TABLE(0b,2b) EX_TABLE(1b,2b)
: "=d" (ret), "+d" (oldval), "=m" (*uaddr)
: "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr)
: "cc", "memory");
disable_sacf_uaccess(old_fs);
*uval = oldval;
return ret;
}
#endif /* _ASM_S390_FUTEX_H */
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