[PATCH 1/3 V3] KVM, SEV: Refactor out function for unregistering encrypted regions

[Peter Gonda <pgonda@google.com>]

Factor out helper function for freeing the encrypted region list.

Signed-off-by: Peter Gonda <pgonda@google.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 arch/x86/kvm/svm/sev.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index b59c464bcdfa..6cb61d36fd5e 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1775,11 +1775,25 @@ int svm_vm_copy_asid_from(struct kvm *kvm, unsigned int source_fd)
 	return ret;
 }
 
+static void unregister_enc_regions(struct kvm *kvm,
+					    struct list_head *mem_regions)
+{
+	struct enc_region *pos, *q;
+
+	lockdep_assert_held(&kvm->lock);
+
+	if (list_empty(mem_regions))
+		return;
+
+	list_for_each_entry_safe(pos, q, mem_regions, list) {
+		__unregister_enc_region_locked(kvm, pos);
+		cond_resched();
+	}
+}
+
 void sev_vm_destroy(struct kvm *kvm)
 {
 	struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
-	struct list_head *head = &sev->regions_list;
-	struct list_head *pos, *q;
 
 	if (!sev_guest(kvm))
 		return;
@@ -1803,13 +1817,7 @@ void sev_vm_destroy(struct kvm *kvm)
 	 * if userspace was terminated before unregistering the memory regions
 	 * then lets unpin all the registered memory.
 	 */
-	if (!list_empty(head)) {
-		list_for_each_safe(pos, q, head) {
-			__unregister_enc_region_locked(kvm,
-				list_entry(pos, struct enc_region, list));
-			cond_resched();
-		}
-	}
+	unregister_enc_regions(kvm, &sev->regions_list);
 
 	mutex_unlock(&kvm->lock);
 
-- 
2.32.0.432.gabb21c7263-goog