diff --git a/drivers/infiniband/sw/rdmavt/mr.c b/drivers/infiniband/sw/rdmavt/mr.c
index 75f158a..80c4b6b 100644
--- a/drivers/infiniband/sw/rdmavt/mr.c
+++ b/drivers/infiniband/sw/rdmavt/mr.c
@@ -140,6 +140,7 @@
 	init_completion(&mr->comp);
 	/* count returning the ptr to user */
 	atomic_set(&mr->refcount, 1);
+	atomic_set(&mr->lkey_invalid, 0);
 	mr->pd = pd;
 	mr->max_segs = count;
 	return 0;
@@ -531,6 +532,72 @@
 }
 
 /**
+ * rvt_fast_reg_mr - fast register physical MR
+ * @qp: the queue pair where the work request comes from
+ * @ibmr: the memory region to be registered
+ * @key: updated key for this memory region
+ * @access: access flags for this memory region
+ *
+ * Returns 0 on success.
+ */
+int rvt_fast_reg_mr(struct rvt_qp *qp, struct ib_mr *ibmr, u32 key,
+		    int access)
+{
+	struct rvt_mr *mr = to_imr(ibmr);
+
+	if (qp->ibqp.pd != mr->mr.pd)
+		return -EACCES;
+
+	/* not applicable to dma MR or user MR */
+	if (!mr->mr.lkey || mr->umem)
+		return -EINVAL;
+
+	if ((key & 0xFFFFFF00) != (mr->mr.lkey & 0xFFFFFF00))
+		return -EINVAL;
+
+	ibmr->lkey = key;
+	ibmr->rkey = key;
+	mr->mr.lkey = key;
+	mr->mr.access_flags = access;
+	atomic_set(&mr->mr.lkey_invalid, 0);
+
+	return 0;
+}
+EXPORT_SYMBOL(rvt_fast_reg_mr);
+
+/**
+ * rvt_invalidate_rkey - invalidate an MR rkey
+ * @qp: queue pair associated with the invalidate op
+ * @rkey: rkey to invalidate
+ *
+ * Returns 0 on success.
+ */
+int rvt_invalidate_rkey(struct rvt_qp *qp, u32 rkey)
+{
+	struct rvt_dev_info *dev = ib_to_rvt(qp->ibqp.device);
+	struct rvt_lkey_table *rkt = &dev->lkey_table;
+	struct rvt_mregion *mr;
+
+	if (rkey == 0)
+		return -EINVAL;
+
+	rcu_read_lock();
+	mr = rcu_dereference(
+		rkt->table[(rkey >> (32 - dev->dparms.lkey_table_size))]);
+	if (unlikely(!mr || mr->lkey != rkey || qp->ibqp.pd != mr->pd))
+		goto bail;
+
+	atomic_set(&mr->lkey_invalid, 1);
+	rcu_read_unlock();
+	return 0;
+
+bail:
+	rcu_read_unlock();
+	return -EINVAL;
+}
+EXPORT_SYMBOL(rvt_invalidate_rkey);
+
+/**
  * rvt_alloc_fmr - allocate a fast memory region
  * @pd: the protection domain for this memory region
  * @mr_access_flags: access flags for this memory region
@@ -733,7 +800,8 @@
 	}
 	mr = rcu_dereference(
 		rkt->table[(sge->lkey >> (32 - dev->dparms.lkey_table_size))]);
-	if (unlikely(!mr || mr->lkey != sge->lkey || mr->pd != &pd->ibpd))
+	if (unlikely(!mr || atomic_read(&mr->lkey_invalid) ||
+		     mr->lkey != sge->lkey || mr->pd != &pd->ibpd))
 		goto bail;
 
 	off = sge->addr - mr->user_base;
@@ -833,7 +901,8 @@
 
 	mr = rcu_dereference(
 		rkt->table[(rkey >> (32 - dev->dparms.lkey_table_size))]);
-	if (unlikely(!mr || mr->lkey != rkey || qp->ibqp.pd != mr->pd))
+	if (unlikely(!mr || atomic_read(&mr->lkey_invalid) ||
+		     mr->lkey != rkey || qp->ibqp.pd != mr->pd))
 		goto bail;
 
 	off = vaddr - mr->iova;