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| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2023-12-05 13:36:16 +0300 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2023-12-07 20:34:01 +0300 |
| commit | cfef5af3cb0e57501dcac2816ab11a20c074866d (patch) | |
| tree | f1acfb6f3b3c37ff9e0c05544e789c76886e6a78 /arch/x86/kvm/kvm_onhyperv.h | |
| parent | 87562052c965ba7de6dc490434e53691fe46c898 (diff) | |
| download | linux-cfef5af3cb0e57501dcac2816ab11a20c074866d.tar.xz | |
KVM: x86: Move Hyper-V partition assist page out of Hyper-V emulation context
Hyper-V partition assist page is used when KVM runs on top of Hyper-V and
is not used for Windows/Hyper-V guests on KVM, this means that 'hv_pa_pg'
placement in 'struct kvm_hv' is unfortunate. As a preparation to making
Hyper-V emulation optional, move 'hv_pa_pg' to 'struct kvm_arch' and put it
under CONFIG_HYPERV.
While on it, introduce hv_get_partition_assist_page() helper to allocate
partition assist page. Move the comment explaining why we use a single page
for all vCPUs from VMX and expand it a bit.
No functional change intended.
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Tested-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20231205103630.1391318-3-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86/kvm/kvm_onhyperv.h')
| -rw-r--r-- | arch/x86/kvm/kvm_onhyperv.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/x86/kvm/kvm_onhyperv.h b/arch/x86/kvm/kvm_onhyperv.h index f9ca3e7432b2..eefab3dc8498 100644 --- a/arch/x86/kvm/kvm_onhyperv.h +++ b/arch/x86/kvm/kvm_onhyperv.h @@ -10,6 +10,26 @@ int hv_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, gfn_t nr_pages); int hv_flush_remote_tlbs(struct kvm *kvm); void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp); +static inline hpa_t hv_get_partition_assist_page(struct kvm_vcpu *vcpu) +{ + /* + * Partition assist page is something which Hyper-V running in L0 + * requires from KVM running in L1 before direct TLB flush for L2 + * guests can be enabled. KVM doesn't currently use the page but to + * comply with TLFS it still needs to be allocated. For now, this + * is a single page shared among all vCPUs. + */ + struct hv_partition_assist_pg **p_hv_pa_pg = + &vcpu->kvm->arch.hv_pa_pg; + + if (!*p_hv_pa_pg) + *p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL_ACCOUNT); + + if (!*p_hv_pa_pg) + return INVALID_PAGE; + + return __pa(*p_hv_pa_pg); +} #else /* !CONFIG_HYPERV */ static inline int hv_flush_remote_tlbs(struct kvm *kvm) { |