1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef __ASM_OPENRISC_FUTEX_H
  3#define __ASM_OPENRISC_FUTEX_H
  4
  5#ifdef __KERNEL__
  6
  7#include <linux/futex.h>
  8#include <linux/uaccess.h>
  9#include <asm/errno.h>
 10
 11#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
 12({								\
 13	__asm__ __volatile__ (					\
 14		"1:	l.lwa	%0, %2			\n"	\
 15			insn				"\n"	\
 16		"2:	l.swa	%2, %1			\n"	\
 17		"	l.bnf	1b			\n"	\
 18		"	 l.ori	%1, r0, 0		\n"	\
 19		"3:					\n"	\
 20		".section .fixup,\"ax\"			\n"	\
 21		"4:	l.j	3b			\n"	\
 22		"	 l.addi	%1, r0, %3		\n"	\
 23		".previous				\n"	\
 24		".section __ex_table,\"a\"		\n"	\
 25		".word	1b,4b,2b,4b			\n"	\
 26		".previous				\n"	\
 27		: "=&r" (oldval), "=&r" (ret), "+m" (*uaddr)	\
 28		: "i" (-EFAULT), "r" (oparg)			\
 29		: "cc", "memory"				\
 30		);						\
 31})
 32
 33static inline int
 34arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
 35{
 36	int oldval = 0, ret;
 37
 38	if (!access_ok(uaddr, sizeof(u32)))
 39		return -EFAULT;
 40
 41	switch (op) {
 42	case FUTEX_OP_SET:
 43		__futex_atomic_op("l.or %1,%4,%4", ret, oldval, uaddr, oparg);
 44		break;
 45	case FUTEX_OP_ADD:
 46		__futex_atomic_op("l.add %1,%0,%4", ret, oldval, uaddr, oparg);
 47		break;
 48	case FUTEX_OP_OR:
 49		__futex_atomic_op("l.or %1,%0,%4", ret, oldval, uaddr, oparg);
 50		break;
 51	case FUTEX_OP_ANDN:
 52		__futex_atomic_op("l.and %1,%0,%4", ret, oldval, uaddr, ~oparg);
 53		break;
 54	case FUTEX_OP_XOR:
 55		__futex_atomic_op("l.xor %1,%0,%4", ret, oldval, uaddr, oparg);
 56		break;
 57	default:
 58		ret = -ENOSYS;
 59	}
 60
 61	if (!ret)
 62		*oval = oldval;
 63
 64	return ret;
 65}
 66
 67static inline int
 68futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 69			      u32 oldval, u32 newval)
 70{
 71	int ret = 0;
 72	u32 prev;
 73
 74	if (!access_ok(uaddr, sizeof(u32)))
 75		return -EFAULT;
 76
 77	__asm__ __volatile__ (				\
 78		"1:	l.lwa	%1, %2		\n"	\
 79		"	l.sfeq	%1, %3		\n"	\
 80		"	l.bnf	3f		\n"	\
 81		"	 l.nop			\n"	\
 82		"2:	l.swa	%2, %4		\n"	\
 83		"	l.bnf	1b		\n"	\
 84		"	 l.nop			\n"	\
 85		"3:				\n"	\
 86		".section .fixup,\"ax\"		\n"	\
 87		"4:	l.j	3b		\n"	\
 88		"	 l.addi	%0, r0, %5	\n"	\
 89		".previous			\n"	\
 90		".section __ex_table,\"a\"	\n"	\
 91		".word	1b,4b,2b,4b		\n"	\
 92		".previous			\n"	\
 93		: "+r" (ret), "=&r" (prev), "+m" (*uaddr) \
 94		: "r" (oldval), "r" (newval), "i" (-EFAULT) \
 95		: "cc",	"memory"			\
 96		);
 97
 98	*uval = prev;
 99	return ret;
100}
101
102#endif /* __KERNEL__ */
103
104#endif /* __ASM_OPENRISC_FUTEX_H */