ubuntu-linux-kernel/arch/mips/kvm/hypcall.c

54 lines
1.3 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* KVM/MIPS: Hypercall handling.
*
* Copyright (C) 2015 Imagination Technologies Ltd.
*/
#include <linux/kernel.h>
#include <linux/kvm_host.h>
#include <linux/kvm_para.h>
#define MAX_HYPCALL_ARGS 4
enum emulation_result kvm_mips_emul_hypcall(struct kvm_vcpu *vcpu,
union mips_instruction inst)
{
unsigned int code = (inst.co_format.code >> 5) & 0x3ff;
kvm_debug("[%#lx] HYPCALL %#03x\n", vcpu->arch.pc, code);
switch (code) {
case 0:
return EMULATE_HYPERCALL;
default:
return EMULATE_FAIL;
};
}
static int kvm_mips_hypercall(struct kvm_vcpu *vcpu, unsigned long num,
const unsigned long *args, unsigned long *hret)
{
/* Report unimplemented hypercall to guest */
*hret = -KVM_ENOSYS;
return RESUME_GUEST;
}
int kvm_mips_handle_hypcall(struct kvm_vcpu *vcpu)
{
unsigned long num, args[MAX_HYPCALL_ARGS];
/* read hypcall number and arguments */
num = vcpu->arch.gprs[2]; /* v0 */
args[0] = vcpu->arch.gprs[4]; /* a0 */
args[1] = vcpu->arch.gprs[5]; /* a1 */
args[2] = vcpu->arch.gprs[6]; /* a2 */
args[3] = vcpu->arch.gprs[7]; /* a3 */
return kvm_mips_hypercall(vcpu, num,
args, &vcpu->arch.gprs[2] /* v0 */);
}