kvm: commonize allocation of the new memory slots

The two kmemdup invocations can be unified.  I find that the new
placement of the comment makes it easier to see what happens.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 11 insertions, 17 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index eae07f97ecf7..7fc77c0f98fb 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -866,11 +866,12 @@ int __kvm_set_memory_region(struct kvm *kvm,
                         goto out_free;
         }
 
+        slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
+                        GFP_KERNEL);
+        if (!slots)
+                goto out_free;
+
         if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
-                slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
-                                GFP_KERNEL);
-                if (!slots)
-                        goto out_free;
                 slot = id_to_memslot(slots, mem->slot);
                 slot->flags |= KVM_MEMSLOT_INVALID;
 
@@ -886,6 +887,12 @@ int __kvm_set_memory_region(struct kvm *kvm,
                  *      - kvm_is_visible_gfn (mmu_check_roots)
                  */
                 kvm_arch_flush_shadow_memslot(kvm, slot);
+
+                /*
+                 * We can re-use the old_memslots from above, the only difference
+                 * from the currently installed memslots is the invalid flag.  This
+                 * will get overwritten by update_memslots anyway.
+                 */
                 slots = old_memslots;
         }
 
@@ -893,19 +900,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
         if (r)
                 goto out_slots;
 
-        r = -ENOMEM;
-        /*
-         * We can re-use the old_memslots from above, the only difference
-         * from the currently installed memslots is the invalid flag.  This
-         * will get overwritten by update_memslots anyway.
-         */
-        if (!slots) {
-                slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
-                                GFP_KERNEL);
-                if (!slots)
-                        goto out_free;
-        }
-
         /* actual memory is freed via old in kvm_free_physmem_slot below */
         if (change == KVM_MR_DELETE) {
                 new.dirty_bitmap = NULL;