/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * KVM L1 hypervisor optimizations on Hyper-V for SVM.
 */

#ifndef __ARCH_X86_KVM_SVM_ONHYPERV_H__
#define __ARCH_X86_KVM_SVM_ONHYPERV_H__

#include <asm/mshyperv.h>

#if IS_ENABLED(CONFIG_HYPERV)

#include "kvm_onhyperv.h"
#include "svm/hyperv.h"

static struct kvm_x86_ops svm_x86_ops;

int svm_hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu);

static inline bool svm_hv_is_enlightened_tlb_enabled(struct kvm_vcpu *vcpu)
{
 struct hv_vmcb_enlightenments *hve = &to_svm(vcpu)->vmcb->control.hv_enlightenments;

 return ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB &&
        !!hve->hv_enlightenments_control.enlightened_npt_tlb;
}

static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
{
 struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;

 BUILD_BUG_ON(sizeof(vmcb->control.hv_enlightenments) !=
       sizeof(vmcb->control.reserved_sw));

 if (npt_enabled &&
     ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB)
  hve->hv_enlightenments_control.enlightened_npt_tlb = 1;

 if (ms_hyperv.nested_features & HV_X64_NESTED_MSR_BITMAP)
  hve->hv_enlightenments_control.msr_bitmap = 1;
}

static inline __init void svm_hv_hardware_setup(void)
{
 if (npt_enabled &&
     ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB) {
  pr_info(KBUILD_MODNAME ": Hyper-V enlightened NPT TLB flush enabled\n");
  svm_x86_ops.flush_remote_tlbs = hv_flush_remote_tlbs;
  svm_x86_ops.flush_remote_tlbs_range = hv_flush_remote_tlbs_range;
 }

 if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH) {
  int cpu;

  pr_info(KBUILD_MODNAME ": Hyper-V Direct TLB Flush enabled\n");
  for_each_online_cpu(cpu) {
   struct hv_vp_assist_page *vp_ap =
    hv_get_vp_assist_page(cpu);

   if (!vp_ap)
    continue;

   vp_ap->nested_control.features.directhypercall = 1;
  }
  svm_x86_ops.enable_l2_tlb_flush =
    svm_hv_enable_l2_tlb_flush;
 }
}

static inline void svm_hv_vmcb_dirty_nested_enlightenments(
  struct kvm_vcpu *vcpu)
{
 struct vmcb *vmcb = to_svm(vcpu)->vmcb;
 struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;

 if (hve->hv_enlightenments_control.msr_bitmap)
  vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
}

static inline void svm_hv_update_vp_id(struct vmcb *vmcb, struct kvm_vcpu *vcpu)
{
 struct hv_vmcb_enlightenments *hve = &vmcb->control.hv_enlightenments;
 u32 vp_index = kvm_hv_get_vpindex(vcpu);

 if (hve->hv_vp_id != vp_index) {
  hve->hv_vp_id = vp_index;
  vmcb_mark_dirty(vmcb, HV_VMCB_NESTED_ENLIGHTENMENTS);
 }
}
#else

static inline bool svm_hv_is_enlightened_tlb_enabled(struct kvm_vcpu *vcpu)
{
 return false;
}

static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
{
}

static inline __init void svm_hv_hardware_setup(void)
{
}

static inline void svm_hv_vmcb_dirty_nested_enlightenments(
  struct kvm_vcpu *vcpu)
{
}

static inline void svm_hv_update_vp_id(struct vmcb *vmcb,
  struct kvm_vcpu *vcpu)
{
}
#endif /* CONFIG_HYPERV */

#endif /* __ARCH_X86_KVM_SVM_ONHYPERV_H__ */