1 files changed, 62 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index ace9efa7aa6c..a26ca569f257 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -652,3 +652,65 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
 	set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags);
 	return -ENOTCONN;
 }
+
+void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
+			 int status)
+{
+	struct ib_send_wr err_wr;
+	struct page *p;
+	struct svc_rdma_op_ctxt *ctxt;
+	enum rpcrdma_errcode err;
+	__be32 *va;
+	int length;
+	int ret;
+
+	ret = svc_rdma_repost_recv(xprt, GFP_KERNEL);
+	if (ret)
+		return;
+
+	p = alloc_page(GFP_KERNEL);
+	if (!p)
+		return;
+	va = page_address(p);
+
+	/* XDR encode an error reply */
+	err = ERR_CHUNK;
+	if (status == -EPROTONOSUPPORT)
+		err = ERR_VERS;
+	length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va);
+
+	ctxt = svc_rdma_get_context(xprt);
+	ctxt->direction = DMA_TO_DEVICE;
+	ctxt->count = 1;
+	ctxt->pages[0] = p;
+
+	/* Prepare SGE for local address */
+	ctxt->sge[0].lkey = xprt->sc_pd->local_dma_lkey;
+	ctxt->sge[0].length = length;
+	ctxt->sge[0].addr = ib_dma_map_page(xprt->sc_cm_id->device,
+					    p, 0, length, DMA_TO_DEVICE);
+	if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[0].addr)) {
+		dprintk("svcrdma: Error mapping buffer for protocol error\n");
+		svc_rdma_put_context(ctxt, 1);
+		return;
+	}
+	atomic_inc(&xprt->sc_dma_used);
+
+	/* Prepare SEND WR */
+	memset(&err_wr, 0, sizeof(err_wr));
+	ctxt->wr_op = IB_WR_SEND;
+	err_wr.wr_id = (unsigned long)ctxt;
+	err_wr.sg_list = ctxt->sge;
+	err_wr.num_sge = 1;
+	err_wr.opcode = IB_WR_SEND;
+	err_wr.send_flags = IB_SEND_SIGNALED;
+
+	/* Post It */
+	ret = svc_rdma_send(xprt, &err_wr);
+	if (ret) {
+		dprintk("svcrdma: Error %d posting send for protocol error\n",
+			ret);
+		svc_rdma_unmap_dma(ctxt);
+		svc_rdma_put_context(ctxt, 1);
+	}
+}