@@ -2742,6 +2742,29 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask);
}
+static bool rmap_write_protect_direct_gfn(struct kvm *kvm,
+ struct kvm_memory_slot *slot,
+ gfn_t gfn)
+{
+ struct direct_walk_iterator iter;
+ u64 new_pte;
+
+ direct_walk_iterator_setup_walk(&iter, kvm, slot->as_id, gfn, gfn + 1,
+ MMU_WRITE_LOCK);
+ while (direct_walk_iterator_next_present_leaf_pte(&iter)) {
+ if (!is_writable_pte(iter.old_pte) &&
+ !spte_can_locklessly_be_made_writable(iter.old_pte))
+ break;
+
+ new_pte = iter.old_pte &
+ ~(PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE);
+
+ if (!direct_walk_iterator_set_pte(&iter, new_pte))
+ continue;
+ }
+ return direct_walk_iterator_end_traversal(&iter);
+}
+
/**
* kvm_arch_write_log_dirty - emulate dirty page logging
* @vcpu: Guest mode vcpu
@@ -2764,6 +2787,10 @@ bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
int i;
bool write_protected = false;
+ if (kvm->arch.direct_mmu_enabled)
+ write_protected |= rmap_write_protect_direct_gfn(kvm, slot,
+ gfn);
+
for (i = PT_PAGE_TABLE_LEVEL; i <= PT_MAX_HUGEPAGE_LEVEL; ++i) {
rmap_head = __gfn_to_rmap(gfn, i, slot);
write_protected |= __rmap_write_protect(kvm, rmap_head, true);
@@ -5755,6 +5782,8 @@ static bool cached_root_available(struct kvm_vcpu *vcpu, gpa_t new_cr3,
uint i;
struct kvm_mmu_root_info root;
struct kvm_mmu *mmu = vcpu->arch.mmu;
+ bool direct_mmu_root = (vcpu->kvm->arch.direct_mmu_enabled &&
+ new_role.direct);
root.cr3 = mmu->root_cr3;
root.hpa = mmu->root_hpa;
@@ -5762,10 +5791,14 @@ static bool cached_root_available(struct kvm_vcpu *vcpu, gpa_t new_cr3,
for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
swap(root, mmu->prev_roots[i]);
- if (new_cr3 == root.cr3 && VALID_PAGE(root.hpa) &&
- page_header(root.hpa) != NULL &&
- new_role.word == page_header(root.hpa)->role.word)
- break;
+ if (new_cr3 == root.cr3 && VALID_PAGE(root.hpa)) {
+ BUG_ON(direct_mmu_root &&
+ !is_direct_mmu_root(vcpu->kvm, root.hpa));
+
+ if (direct_mmu_root || (page_header(root.hpa) != NULL &&
+ new_role.word == page_header(root.hpa)->role.word))
+ break;
+ }
}
mmu->root_hpa = root.hpa;
@@ -5813,8 +5846,14 @@ static bool fast_cr3_switch(struct kvm_vcpu *vcpu, gpa_t new_cr3,
*/
vcpu_clear_mmio_info(vcpu, MMIO_GVA_ANY);
- __clear_sp_write_flooding_count(
- page_header(mmu->root_hpa));
+ /*
+ * If this is a direct MMU root page, it doesn't have a
+ * write flooding count.
+ */
+ if (!(vcpu->kvm->arch.direct_mmu_enabled &&
+ new_role.direct))
+ __clear_sp_write_flooding_count(
+ page_header(mmu->root_hpa));
return true;
}
Allows the existing nesting implementation to interoperate with the direct MMU. Signed-off-by: Ben Gardon <bgardon@google.com> --- arch/x86/kvm/mmu.c | 51 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 45 insertions(+), 6 deletions(-)