diff options
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/kvm/vmx.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index eda2cb6..914dc4e 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -145,12 +145,53 @@ struct shared_msr_entry { }; /* + * struct vmcs12 describes the state that our guest hypervisor (L1) keeps for a + * single nested guest (L2), hence the name vmcs12. Any VMX implementation has + * a VMCS structure, and vmcs12 is our emulated VMX's VMCS. This structure is + * stored in guest memory specified by VMPTRLD, but is opaque to the guest, + * which must access it using VMREAD/VMWRITE/VMCLEAR instructions. + * More than one of these structures may exist, if L1 runs multiple L2 guests. + * nested_vmx_run() will use the data here to build a vmcs02: a VMCS for the + * underlying hardware which will be used to run L2. + * This structure is packed to ensure that its layout is identical across + * machines (necessary for live migration). + * If there are changes in this struct, VMCS12_REVISION must be changed. + */ +struct __packed vmcs12 { + /* According to the Intel spec, a VMCS region must start with the + * following two fields. Then follow implementation-specific data. + */ + u32 revision_id; + u32 abort; +}; + +/* + * VMCS12_REVISION is an arbitrary id that should be changed if the content or + * layout of struct vmcs12 is changed. MSR_IA32_VMX_BASIC returns this id, and + * VMPTRLD verifies that the VMCS region that L1 is loading contains this id. + */ +#define VMCS12_REVISION 0x11e57ed0 + +/* + * VMCS12_SIZE is the number of bytes L1 should allocate for the VMXON region + * and any VMCS region. Although only sizeof(struct vmcs12) are used by the + * current implementation, 4K are reserved to avoid future complications. + */ +#define VMCS12_SIZE 0x1000 + +/* * The nested_vmx structure is part of vcpu_vmx, and holds information we need * for correct emulation of VMX (i.e., nested VMX) on this vcpu. */ struct nested_vmx { /* Has the level1 guest done vmxon? */ bool vmxon; + + /* The guest-physical address of the current VMCS L1 keeps for L2 */ + gpa_t current_vmptr; + /* The host-usable pointer to the above */ + struct page *current_vmcs12_page; + struct vmcs12 *current_vmcs12; }; struct vcpu_vmx { @@ -231,6 +272,31 @@ static inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu) return container_of(vcpu, struct vcpu_vmx, vcpu); } +static inline struct vmcs12 *get_vmcs12(struct kvm_vcpu *vcpu) +{ + return to_vmx(vcpu)->nested.current_vmcs12; +} + +static struct page *nested_get_page(struct kvm_vcpu *vcpu, gpa_t addr) +{ + struct page *page = gfn_to_page(vcpu->kvm, addr >> PAGE_SHIFT); + if (is_error_page(page)) { + kvm_release_page_clean(page); + return NULL; + } + return page; +} + +static void nested_release_page(struct page *page) +{ + kvm_release_page_dirty(page); +} + +static void nested_release_page_clean(struct page *page) +{ + kvm_release_page_clean(page); +} + static u64 construct_eptp(unsigned long root_hpa); static void kvm_cpu_vmxon(u64 addr); static void kvm_cpu_vmxoff(void); @@ -4039,6 +4105,12 @@ static void free_nested(struct vcpu_vmx *vmx) if (!vmx->nested.vmxon) return; vmx->nested.vmxon = false; + if (vmx->nested.current_vmptr != -1ull) { + kunmap(vmx->nested.current_vmcs12_page); + nested_release_page(vmx->nested.current_vmcs12_page); + vmx->nested.current_vmptr = -1ull; + vmx->nested.current_vmcs12 = NULL; + } } /* Emulate the VMXOFF instruction */ @@ -4543,6 +4615,9 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) goto free_vmcs; } + vmx->nested.current_vmptr = -1ull; + vmx->nested.current_vmcs12 = NULL; + return &vmx->vcpu; free_vmcs: |