diff --git a/sys/fs/nfsclient/nfs_clvnops.c b/sys/fs/nfsclient/nfs_clvnops.c
--- a/sys/fs/nfsclient/nfs_clvnops.c
+++ b/sys/fs/nfsclient/nfs_clvnops.c
@@ -3872,13 +3872,14 @@
 	struct vnode *invp = ap->a_invp;
 	struct vnode *outvp = ap->a_outvp;
 	struct mount *mp;
+	vm_object_t invp_obj;
 	struct nfsvattr innfsva, outnfsva;
 	struct vattr va, *vap;
 	struct uio io;
 	struct nfsmount *nmp;
 	size_t len, len2;
 	ssize_t r;
-	int error, inattrflag, outattrflag, ret, ret2;
+	int error, inattrflag, outattrflag, ret, ret2, invp_lock;
 	off_t inoff, outoff;
 	bool consecutive, must_commit, tryoutcred;
 
@@ -3891,6 +3892,9 @@
 		return (ENOSYS);
 	}
 
+	invp_lock = LK_SHARED;
+relock:
+
 	/* Lock both vnodes, avoiding risk of deadlock. */
 	do {
 		mp = NULL;
@@ -3898,14 +3902,14 @@
 		if (error == 0) {
 			error = vn_lock(outvp, LK_EXCLUSIVE);
 			if (error == 0) {
-				error = vn_lock(invp, LK_SHARED | LK_NOWAIT);
+				error = vn_lock(invp, invp_lock | LK_NOWAIT);
 				if (error == 0)
 					break;
 				VOP_UNLOCK(outvp);
 				if (mp != NULL)
 					vn_finished_write(mp);
 				mp = NULL;
-				error = vn_lock(invp, LK_SHARED);
+				error = vn_lock(invp, invp_lock);
 				if (error == 0)
 					VOP_UNLOCK(invp);
 			}
@@ -3953,10 +3957,25 @@
 	 * stable storage before the Copy RPC.  This is done in case the
 	 * server reboots during the Copy and needs to be redone.
 	 */
-	if (error == 0)
+	if (error == 0) {
+		invp_obj = invp->v_object;
+		if (invp_obj != NULL && vm_object_mightbedirty(invp_obj)) {
+			if (invp_lock != LK_EXCLUSIVE) {
+				invp_lock = LK_EXCLUSIVE;
+				VOP_UNLOCK(invp);
+				VOP_UNLOCK(outvp);
+				if (mp != NULL)
+					vn_finished_write(mp);
+				goto relock;
+			}
+			VM_OBJECT_WLOCK(invp_obj);
+			vm_object_page_clean(invp_obj, 0, 0, OBJPC_SYNC);
+			VM_OBJECT_WUNLOCK(invp_obj);
+		}
 		error = ncl_flush(invp, MNT_WAIT, curthread, 1, 0);
+	}
 	if (error == 0)
-		error = ncl_flush(outvp, MNT_WAIT, curthread, 1, 0);
+		error = ncl_vinvalbuf(outvp, V_SAVE, curthread, 0);
 
 	/* Do the actual NFSv4.2 RPC. */
 	ret = ret2 = 0;