#ifndef _ASM_MICROBLAZE_FUTEX_H
#define _ASM_MICROBLAZE_FUTEX_H

#ifdef __KERNEL__

#include <linux/futex.h>
#include <linux/uaccess.h>
#include <asm/errno.h>

#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
({ \
__asm__ __volatile__ ( \
"1: lwx %0, %2, r0; " \
insn \
"2: swx %1, %2, r0; \
addic %1, r0, 0; \
bnei %1, 1b; \
3: \
.section .fixup,\"ax\"; \
4: brid 3b; \
addik %1, r0, %3; \
.previous; \
.section __ex_table,\"a\"; \
.word 1b,4b,2b,4b; \
.previous;" \
: "=&r" (oldval), "=&r" (ret) \
: "r" (uaddr), "i" (-EFAULT), "r" (oparg) \
); \
})

static inline int
futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
{
int op = (encoded_op >> 28) & 7;
int cmp = (encoded_op >> 24) & 15;
int oparg = (encoded_op << 8) >> 20;
int cmparg = (encoded_op << 20) >> 20;
int oldval = 0, ret;
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
oparg = 1 << oparg;

if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
return -EFAULT;

pagefault_disable();

switch (op) {
case FUTEX_OP_SET:
__futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg);
break;
default:
ret = -ENOSYS;
}

pagefault_enable();

if (!ret) {
switch (cmp) {
case FUTEX_OP_CMP_EQ:
ret = (oldval == cmparg);
break;
case FUTEX_OP_CMP_NE:
ret = (oldval != cmparg);
break;
case FUTEX_OP_CMP_LT:
ret = (oldval < cmparg);
break;
case FUTEX_OP_CMP_GE:
ret = (oldval >= cmparg);
break;
case FUTEX_OP_CMP_LE:
ret = (oldval <= cmparg);
break;
case FUTEX_OP_CMP_GT:
ret = (oldval > cmparg);
break;
default:
ret = -ENOSYS;
}
}
return ret;
}

static inline int
futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
u32 oldval, u32 newval)
{
int ret = 0, cmp;
u32 prev;

if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
return -EFAULT;

__asm__ __volatile__ ("1: lwx %1, %3, r0; \
cmp %2, %1, %4; \
bnei %2, 3f; \
2: swx %5, %3, r0; \
addic %2, r0, 0; \
bnei %2, 1b; \
3: \
.section .fixup,\"ax\"; \
4: brid 3b; \
addik %0, r0, %6; \
.previous; \
.section __ex_table,\"a\"; \
.word 1b,4b,2b,4b; \
.previous;" \
: "+r" (ret), "=&r" (prev), "=&r"(cmp) \
: "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT));

*uval = prev;
return ret;
}

#endif /* __KERNEL__ */

#endif