1/* SPDX-License-Identifier: GPL-2.0-only */
 2/*
 3 * KVM L1 hypervisor optimizations on Hyper-V.
 4 */
 5
 6#ifndef __ARCH_X86_KVM_KVM_ONHYPERV_H__
 7#define __ARCH_X86_KVM_KVM_ONHYPERV_H__
 8
 9#if IS_ENABLED(CONFIG_HYPERV)
10int hv_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, gfn_t nr_pages);
11int hv_flush_remote_tlbs(struct kvm *kvm);
12void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp);
13static inline hpa_t hv_get_partition_assist_page(struct kvm_vcpu *vcpu)
14{
15	/*
16	 * Partition assist page is something which Hyper-V running in L0
17	 * requires from KVM running in L1 before direct TLB flush for L2
18	 * guests can be enabled. KVM doesn't currently use the page but to
19	 * comply with TLFS it still needs to be allocated. For now, this
20	 * is a single page shared among all vCPUs.
21	 */
22	struct hv_partition_assist_pg **p_hv_pa_pg =
23		&vcpu->kvm->arch.hv_pa_pg;
24
25	if (!*p_hv_pa_pg)
26		*p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL_ACCOUNT);
27
28	if (!*p_hv_pa_pg)
29		return INVALID_PAGE;
30
31	return __pa(*p_hv_pa_pg);
32}
33#else /* !CONFIG_HYPERV */
34static inline int hv_flush_remote_tlbs(struct kvm *kvm)
35{
36	return -EOPNOTSUPP;
37}
38
39static inline void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp)
40{
41}
42#endif /* !CONFIG_HYPERV */
43
44#endif