Commit 10ccaa1e authored by Cornelia Huck's avatar Cornelia Huck Committed by Marcelo Tosatti
Browse files

KVM: s390: Wire up ioeventfd. 



Enable ioeventfd support on s390 and hook up diagnose 500 virtio-ccw
notifications.

Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 2b83451b

arch/s390/kvm/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ config KVM 
	select PREEMPT_NOTIFIERS

	select ANON_INODES

	select HAVE_KVM_CPU_RELAX_INTERCEPT

	select HAVE_KVM_EVENTFD

	---help---

	  Support hosting paravirtualized guest machines using the SIE

	  virtualization capability on the mainframe. This should work

arch/s390/kvm/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ 
# it under the terms of the GNU General Public License (version 2 only)

# as published by the Free Software Foundation.



common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o)

common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o eventfd.o)



ccflags-y := -Ivirt/kvm -Iarch/s390/kvm

arch/s390/kvm/diag.c

+26 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 


#include <linux/kvm.h>

#include <linux/kvm_host.h>

#include <asm/virtio-ccw.h>

#include "kvm-s390.h"

#include "trace.h"

#include "trace-s390.h"
@@ -104,6 +105,29 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu) 
	return -EREMOTE;

}



static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)

{

	int ret, idx;



	/* No virtio-ccw notification? Get out quickly. */

	if (!vcpu->kvm->arch.css_support ||

	    (vcpu->run->s.regs.gprs[1] != KVM_S390_VIRTIO_CCW_NOTIFY))

		return -EOPNOTSUPP;



	idx = srcu_read_lock(&vcpu->kvm->srcu);

	/*

	 * The layout is as follows:

	 * - gpr 2 contains the subchannel id (passed as addr)

	 * - gpr 3 contains the virtqueue index (passed as datamatch)

	 */

	ret = kvm_io_bus_write(vcpu->kvm, KVM_VIRTIO_CCW_NOTIFY_BUS,

				vcpu->run->s.regs.gprs[2],

				8, &vcpu->run->s.regs.gprs[3]);

	srcu_read_unlock(&vcpu->kvm->srcu, idx);

	/* kvm_io_bus_write returns -EOPNOTSUPP if it found no match. */

	return ret < 0 ? ret : 0;

}



int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)

{

	int code = (vcpu->arch.sie_block->ipb & 0xfff0000) >> 16;
@@ -118,6 +142,8 @@ int kvm_s390_handle_diag(struct kvm_vcpu *vcpu) 
		return __diag_time_slice_end_directed(vcpu);

	case 0x308:

		return __diag_ipl_functions(vcpu);

	case 0x500:

		return __diag_virtio_hypercall(vcpu);

	default:

		return -EOPNOTSUPP;

	}

arch/s390/kvm/kvm-s390.c

+1 −0
Original line number Diff line number Diff line
@@ -142,6 +142,7 @@ int kvm_dev_ioctl_check_extension(long ext) 
	case KVM_CAP_ONE_REG:

	case KVM_CAP_ENABLE_CAP:

	case KVM_CAP_S390_CSS_SUPPORT:

	case KVM_CAP_IOEVENTFD:

		r = 1;

		break;

	case KVM_CAP_NR_VCPUS: