linux/arch/x86/kvm/svm/svm_onhyperv.c
Vineeth Pillai 1183646a67 KVM: SVM: hyper-v: Direct Virtual Flush support
From Hyper-V TLFS:
 "The hypervisor exposes hypercalls (HvFlushVirtualAddressSpace,
  HvFlushVirtualAddressSpaceEx, HvFlushVirtualAddressList, and
  HvFlushVirtualAddressListEx) that allow operating systems to more
  efficiently manage the virtual TLB. The L1 hypervisor can choose to
  allow its guest to use those hypercalls and delegate the responsibility
  to handle them to the L0 hypervisor. This requires the use of a
  partition assist page."

Add the Direct Virtual Flush support for SVM.

Related VMX changes:
commit 6f6a657c99 ("KVM/Hyper-V/VMX: Add direct tlb flush support")

Signed-off-by: Vineeth Pillai <viremana@linux.microsoft.com>
Message-Id: <fc8d24d8eb7017266bb961e39a171b0caf298d7f.1622730232.git.viremana@linux.microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-17 13:09:38 -04:00

42 lines
961 B
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* KVM L1 hypervisor optimizations on Hyper-V for SVM.
*/
#include <linux/kvm_host.h>
#include "kvm_cache_regs.h"
#include <asm/mshyperv.h>
#include "svm.h"
#include "svm_ops.h"
#include "hyperv.h"
#include "kvm_onhyperv.h"
#include "svm_onhyperv.h"
int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu)
{
struct hv_enlightenments *hve;
struct hv_partition_assist_pg **p_hv_pa_pg =
&to_kvm_hv(vcpu->kvm)->hv_pa_pg;
if (!*p_hv_pa_pg)
*p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL);
if (!*p_hv_pa_pg)
return -ENOMEM;
hve = (struct hv_enlightenments *)to_svm(vcpu)->vmcb->control.reserved_sw;
hve->partition_assist_page = __pa(*p_hv_pa_pg);
hve->hv_vm_id = (unsigned long)vcpu->kvm;
if (!hve->hv_enlightenments_control.nested_flush_hypercall) {
hve->hv_enlightenments_control.nested_flush_hypercall = 1;
vmcb_mark_dirty(to_svm(vcpu)->vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS);
}
return 0;
}