KVM: MMU: Add EPT support

Enable kvm_set_spte() to generate EPT entries.

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 20fb3c8..c28a36b 100644 (file)
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -152,6 +152,12 @@ static struct kmem_cache *mmu_page_header_cache;
 
 static u64 __read_mostly shadow_trap_nonpresent_pte;
 static u64 __read_mostly shadow_notrap_nonpresent_pte;
+static u64 __read_mostly shadow_base_present_pte;
+static u64 __read_mostly shadow_nx_mask;
+static u64 __read_mostly shadow_x_mask;        /* mutual exclusive with nx_mask */
+static u64 __read_mostly shadow_user_mask;
+static u64 __read_mostly shadow_accessed_mask;
+static u64 __read_mostly shadow_dirty_mask;
 
 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte)
 {
@@ -160,6 +166,23 @@ void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte)
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes);
 
+void kvm_mmu_set_base_ptes(u64 base_pte)
+{
+       shadow_base_present_pte = base_pte;
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_set_base_ptes);
+
+void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
+               u64 dirty_mask, u64 nx_mask, u64 x_mask)
+{
+       shadow_user_mask = user_mask;
+       shadow_accessed_mask = accessed_mask;
+       shadow_dirty_mask = dirty_mask;
+       shadow_nx_mask = nx_mask;
+       shadow_x_mask = x_mask;
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes);
+
 static int is_write_protection(struct kvm_vcpu *vcpu)
 {
        return vcpu->arch.cr0 & X86_CR0_WP;
@@ -198,7 +221,7 @@ static int is_writeble_pte(unsigned long pte)
 
 static int is_dirty_pte(unsigned long pte)
 {
-       return pte & PT_DIRTY_MASK;
+       return pte & shadow_dirty_mask;
 }
 
 static int is_rmap_pte(u64 pte)
@@ -513,7 +536,7 @@ static void rmap_remove(struct kvm *kvm, u64 *spte)
                return;
        sp = page_header(__pa(spte));
        pfn = spte_to_pfn(*spte);
-       if (*spte & PT_ACCESSED_MASK)
+       if (*spte & shadow_accessed_mask)
                kvm_set_pfn_accessed(pfn);
        if (is_writeble_pte(*spte))
                kvm_release_pfn_dirty(pfn);
@@ -1039,17 +1062,17 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
         * whether the guest actually used the pte (in order to detect
         * demand paging).
         */
-       spte = PT_PRESENT_MASK | PT_DIRTY_MASK;
+       spte = shadow_base_present_pte | shadow_dirty_mask;
        if (!speculative)
                pte_access |= PT_ACCESSED_MASK;
        if (!dirty)
                pte_access &= ~ACC_WRITE_MASK;
-       if (!(pte_access & ACC_EXEC_MASK))
-               spte |= PT64_NX_MASK;
-
-       spte |= PT_PRESENT_MASK;
+       if (pte_access & ACC_EXEC_MASK)
+               spte |= shadow_x_mask;
+       else
+               spte |= shadow_nx_mask;
        if (pte_access & ACC_USER_MASK)
-               spte |= PT_USER_MASK;
+               spte |= shadow_user_mask;
        if (largepage)
                spte |= PT_PAGE_SIZE_MASK;
 
@@ -1155,7 +1178,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
                        }
 
                        table[index] = __pa(new_table->spt) | PT_PRESENT_MASK
-                               | PT_WRITABLE_MASK | PT_USER_MASK;
+                               | PT_WRITABLE_MASK | shadow_user_mask;
                }
                table_addr = table[index] & PT64_BASE_ADDR_MASK;
        }
@@ -1599,7 +1622,7 @@ static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu)
 {
        u64 *spte = vcpu->arch.last_pte_updated;
 
-       return !!(spte && (*spte & PT_ACCESSED_MASK));
+       return !!(spte && (*spte & shadow_accessed_mask));
 }
 
 static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0ce5563..0735efb 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2417,6 +2417,9 @@ int kvm_arch_init(void *opaque)
 
        kvm_x86_ops = ops;
        kvm_mmu_set_nonpresent_ptes(0ull, 0ull);
+       kvm_mmu_set_base_ptes(PT_PRESENT_MASK);
+       kvm_mmu_set_mask_ptes(PT_USER_MASK, PT_ACCESSED_MASK,
+                       PT_DIRTY_MASK, PT64_NX_MASK, 0);
        return 0;
 
 out:

diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
index 897a1be..d1dedda 100644 (file)
--- a/include/asm-x86/kvm_host.h
+++ b/include/asm-x86/kvm_host.h
@@ -434,6 +434,9 @@ void kvm_mmu_destroy(struct kvm_vcpu *vcpu);
 int kvm_mmu_create(struct kvm_vcpu *vcpu);
 int kvm_mmu_setup(struct kvm_vcpu *vcpu);
 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte);
+void kvm_mmu_set_base_ptes(u64 base_pte);
+void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
+               u64 dirty_mask, u64 nx_mask, u64 x_mask);
 
 int kvm_mmu_reset_context(struct kvm_vcpu *vcpu);
 void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot);