KVM: cleanup allocation of rmaps and page tracking data

Unify the flags for rmaps and page tracking data, using a
single flag in struct kvm_arch and a single loop to go
over all the address spaces and memslots.  This avoids
code duplication between alloc_all_memslots_rmaps and
kvm_page_track_enable_mmu_write_tracking.

Signed-off-by: David Stevens <stevensd@chromium.org>
[This patch is the delta between David's v2 and v3, with conflicts
 fixed and my own commit message. - Paolo]
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 17 insertions, 5 deletions

diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 75367af1a6d3..2df48d60c949 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -304,14 +304,26 @@ int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu);
 int kvm_mmu_post_init_vm(struct kvm *kvm);
 void kvm_mmu_pre_destroy_vm(struct kvm *kvm);
 
-static inline bool kvm_memslots_have_rmaps(struct kvm *kvm)
+static inline bool kvm_shadow_root_allocated(struct kvm *kvm)
 {
 	/*
-	 * Read memslot_have_rmaps before rmap pointers.  Hence, threads reading
-	 * memslots_have_rmaps in any lock context are guaranteed to see the
-	 * pointers.  Pairs with smp_store_release in alloc_all_memslots_rmaps.
+	 * Read shadow_root_allocated before related pointers. Hence, threads
+	 * reading shadow_root_allocated in any lock context are guaranteed to
+	 * see the pointers. Pairs with smp_store_release in
+	 * mmu_first_shadow_root_alloc.
 	 */
-	return smp_load_acquire(&kvm->arch.memslots_have_rmaps);
+	return smp_load_acquire(&kvm->arch.shadow_root_allocated);
+}
+
+#ifdef CONFIG_X86_64
+static inline bool is_tdp_mmu_enabled(struct kvm *kvm) { return kvm->arch.tdp_mmu_enabled; }
+#else
+static inline bool is_tdp_mmu_enabled(struct kvm *kvm) { return false; }
+#endif
+
+static inline bool kvm_memslots_have_rmaps(struct kvm *kvm)
+{
+	return !is_tdp_mmu_enabled(kvm) || kvm_shadow_root_allocated(kvm);
 }
 
 static inline gfn_t gfn_to_index(gfn_t gfn, gfn_t base_gfn, int level)