KVM: arm64: Use "new" memslot instead of userspace memory region

Get the slot ID, hva, etc... from the "new" memslot instead of the
userspace memory region when preparing/committing a memory region.  This
will allow a future commit to drop @mem from the prepare/commit hooks
once all architectures convert to using "new".

Opportunistically wait to get the hva begin+end until after filtering out
the DELETE case in anticipation of a future commit passing NULL for @new
when deleting a memslot.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <c019d00c2531520c52e0b52dfda1be5aa898103c.1638817639.git.maciej.szmigiero@oracle.com>

arch/arm64/kvm/mmu.c

@@ -1473,14 +1473,14 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
 	 * allocated dirty_bitmap[], dirty pages will be tracked while the
 	 * memory slot is write protected.
 	 */
-	if (change != KVM_MR_DELETE && mem->flags & KVM_MEM_LOG_DIRTY_PAGES) {
+	if (change != KVM_MR_DELETE && new->flags & KVM_MEM_LOG_DIRTY_PAGES) {
 		/*
 		 * If we're with initial-all-set, we don't need to write
 		 * protect any pages because they're all reported as dirty.
 		 * Huge pages and normal pages will be write protect gradually.
 		 */
 		if (!kvm_dirty_log_manual_protect_and_init_set(kvm)) {
-			kvm_mmu_wp_memory_region(kvm, mem->slot);
+			kvm_mmu_wp_memory_region(kvm, new->id);
 		}
 	}
 }
@@ -1491,8 +1491,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 				   struct kvm_memory_slot *new,
 				   enum kvm_mr_change change)
 {
-	hva_t hva = mem->userspace_addr;
-	hva_t reg_end = hva + mem->memory_size;
+	hva_t hva, reg_end;
 	int ret = 0;
 
 	if (change != KVM_MR_CREATE && change != KVM_MR_MOVE &&
@@ -1506,6 +1505,9 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 	if ((new->base_gfn + new->npages) > (kvm_phys_size(kvm) >> PAGE_SHIFT))
 		return -EFAULT;
 
+	hva = new->userspace_addr;
+	reg_end = hva + (new->npages << PAGE_SHIFT);
+
 	mmap_read_lock(current->mm);
 	/*
 	 * A memory region could potentially cover multiple VMAs, and any holes