arch/x86/kvm/svm/svm_onhyperv.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * KVM L1 hypervisor optimizations on Hyper-V for SVM.
   4  */
   5
   6 #ifndef __ARCH_X86_KVM_SVM_ONHYPERV_H__
   7 #define __ARCH_X86_KVM_SVM_ONHYPERV_H__
   8
   9 #if IS_ENABLED(CONFIG_HYPERV)
  10 #include <asm/mshyperv.h>
  11
  12 #include "hyperv.h"
  13 #include "kvm_onhyperv.h"
  14
  15 static struct kvm_x86_ops svm_x86_ops;
  16
  17 /*
  18  * Hyper-V uses the software reserved 32 bytes in VMCB
  19  * control area to expose SVM enlightenments to guests.
  20  */
  21 struct hv_enlightenments {
  22         struct __packed hv_enlightenments_control {
  23                 u32 nested_flush_hypercall:1;
  24                 u32 msr_bitmap:1;
  25                 u32 enlightened_npt_tlb: 1;
  26                 u32 reserved:29;
  27         } __packed hv_enlightenments_control;
  28         u32 hv_vp_id;
  29         u64 hv_vm_id;
  30         u64 partition_assist_page;
  31         u64 reserved;
  32 } __packed;
  33
  34 /*
  35  * Hyper-V uses the software reserved clean bit in VMCB
  36  */
  37 #define VMCB_HV_NESTED_ENLIGHTENMENTS VMCB_SW
  38
  39 int svm_hv_enable_direct_tlbflush(struct kvm_vcpu *vcpu);
  40
  41 static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
  42 {
  43         struct hv_enlightenments *hve =
  44                 (struct hv_enlightenments *)vmcb->control.reserved_sw;
  45
  46         if (npt_enabled &&
  47             ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB)
  48                 hve->hv_enlightenments_control.enlightened_npt_tlb = 1;
  49 }
  50
  51 static inline void svm_hv_hardware_setup(void)
  52 {
  53         if (npt_enabled &&
  54             ms_hyperv.nested_features & HV_X64_NESTED_ENLIGHTENED_TLB) {
  55                 pr_info("kvm: Hyper-V enlightened NPT TLB flush enabled\n");
  56                 svm_x86_ops.tlb_remote_flush = hv_remote_flush_tlb;
  57                 svm_x86_ops.tlb_remote_flush_with_range =
  58                                 hv_remote_flush_tlb_with_range;
  59         }
  60
  61         if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH) {
  62                 int cpu;
  63
  64                 pr_info("kvm: Hyper-V Direct TLB Flush enabled\n");
  65                 for_each_online_cpu(cpu) {
  66                         struct hv_vp_assist_page *vp_ap =
  67                                 hv_get_vp_assist_page(cpu);
  68
  69                         if (!vp_ap)
  70                                 continue;
  71
  72                         vp_ap->nested_control.features.directhypercall = 1;
  73                 }
  74                 svm_x86_ops.enable_direct_tlbflush =
  75                                 svm_hv_enable_direct_tlbflush;
  76         }
  77 }
  78
  79 static inline void svm_hv_vmcb_dirty_nested_enlightenments(
  80                 struct kvm_vcpu *vcpu)
  81 {
  82         struct vmcb *vmcb = to_svm(vcpu)->vmcb;
  83         struct hv_enlightenments *hve =
  84                 (struct hv_enlightenments *)vmcb->control.reserved_sw;
  85
  86         /*
  87          * vmcb can be NULL if called during early vcpu init.
  88          * And its okay not to mark vmcb dirty during vcpu init
  89          * as we mark it dirty unconditionally towards end of vcpu
  90          * init phase.
  91          */
  92         if (vmcb && vmcb_is_clean(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS) &&
  93             hve->hv_enlightenments_control.msr_bitmap)
  94                 vmcb_mark_dirty(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS);
  95 }
  96
  97 static inline void svm_hv_update_vp_id(struct vmcb *vmcb,
  98                 struct kvm_vcpu *vcpu)
  99 {
 100         struct hv_enlightenments *hve =
 101                 (struct hv_enlightenments *)vmcb->control.reserved_sw;
 102         u32 vp_index = kvm_hv_get_vpindex(vcpu);
 103
 104         if (hve->hv_vp_id != vp_index) {
 105                 hve->hv_vp_id = vp_index;
 106                 vmcb_mark_dirty(vmcb, VMCB_HV_NESTED_ENLIGHTENMENTS);
 107         }
 108 }
 109 #else
 110
 111 static inline void svm_hv_init_vmcb(struct vmcb *vmcb)
 112 {
 113 }
 114
 115 static inline void svm_hv_hardware_setup(void)
 116 {
 117 }
 118
 119 static inline void svm_hv_vmcb_dirty_nested_enlightenments(
 120                 struct kvm_vcpu *vcpu)
 121 {
 122 }
 123
 124 static inline void svm_hv_update_vp_id(struct vmcb *vmcb,
 125                 struct kvm_vcpu *vcpu)
 126 {
 127 }
 128 #endif /* CONFIG_HYPERV */
 129
 130 #endif /* __ARCH_X86_KVM_SVM_ONHYPERV_H__ */