#ifndef __ASM_E2K_KVM_SPINLOCK_H
#define __ASM_E2K_KVM_SPINLOCK_H
/*
 * This file implements the arch-dependent parts of kvm guest
 * spin_lock()/spin_unlock() slow part
 *
 * Copyright 2014 Salavat S. Guiliazov (atic@mcst.ru)
 */

#include <linux/types.h>
#include <linux/spinlock_types.h>

#if	defined(CONFIG_PARAVIRT_GUEST)
/* it is paravirtualized host and guest kernel */
#include <asm/paravirt/spinlock.h>
#elif	defined(CONFIG_KVM_GUEST_KERNEL)
/* it is pure guest kernel (not paravirtualized based on pv_ops) */
#include <asm/kvm/guest/spinlock.h>
#else
 #error "Unknown virtualization type"
#endif	/* CONFIG_PARAVIRT_GUEST */

static inline void arch_spin_unlock(arch_spinlock_t *lock)
{
	arch_spinlock_t val;
	u16 ticket, ready;

	wmb();	/* wait for all store completion */
	val.lock = __api_atomic16_add_return32_lock(
			1 << ARCH_SPINLOCK_HEAD_SHIFT, &lock->lock);
	ticket = val.tail;
	ready = val.head;

	if (unlikely(ticket != ready)) {
		/* spinlock has more user(s): so activate it(s) */
		arch_spin_unlock_slow(lock);
	}
}

#endif	/* __ASM_E2K_KVM_SPINLOCK_H */