1 files changed, 60 insertions, 22 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index 54d53330..f5a91ed 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -225,6 +225,48 @@ svc_rdma_get_reply_array(struct rpcrdma_msg *rmsgp,
 	return rp_ary;
 }
 
+/* RPC-over-RDMA Version One private extension: Remote Invalidation.
+ * Responder's choice: requester signals it can handle Send With
+ * Invalidate, and responder chooses one rkey to invalidate.
+ *
+ * Find a candidate rkey to invalidate when sending a reply.  Picks the
+ * first rkey it finds in the chunks lists.
+ *
+ * Returns zero if RPC's chunk lists are empty.
+ */
+static u32 svc_rdma_get_inv_rkey(struct rpcrdma_msg *rdma_argp,
+				 struct rpcrdma_write_array *wr_ary,
+				 struct rpcrdma_write_array *rp_ary)
+{
+	struct rpcrdma_read_chunk *rd_ary;
+	struct rpcrdma_segment *arg_ch;
+	u32 inv_rkey;
+
+	inv_rkey = 0;
+
+	rd_ary = svc_rdma_get_read_chunk(rdma_argp);
+	if (rd_ary) {
+		inv_rkey = be32_to_cpu(rd_ary->rc_target.rs_handle);
+		goto out;
+	}
+
+	if (wr_ary && be32_to_cpu(wr_ary->wc_nchunks)) {
+		arg_ch = &wr_ary->wc_array[0].wc_target;
+		inv_rkey = be32_to_cpu(arg_ch->rs_handle);
+		goto out;
+	}
+
+	if (rp_ary && be32_to_cpu(rp_ary->wc_nchunks)) {
+		arg_ch = &rp_ary->wc_array[0].wc_target;
+		inv_rkey = be32_to_cpu(arg_ch->rs_handle);
+		goto out;
+	}
+
+out:
+	dprintk("svcrdma: Send With Invalidate rkey=%08x\n", inv_rkey);
+	return inv_rkey;
+}
+
 /* Assumptions:
  * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE
  */
@@ -280,7 +322,7 @@ static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp,
 		if (ib_dma_mapping_error(xprt->sc_cm_id->device,
 					 sge[sge_no].addr))
 			goto err;
-		atomic_inc(&xprt->sc_dma_used);
+		svc_rdma_count_mappings(xprt, ctxt);
 		sge[sge_no].lkey = xprt->sc_pd->local_dma_lkey;
 		ctxt->count++;
 		sge_off = 0;
@@ -464,7 +506,8 @@ static int send_reply(struct svcxprt_rdma *rdma,
 		      struct page *page,
 		      struct rpcrdma_msg *rdma_resp,
 		      struct svc_rdma_req_map *vec,
-		      int byte_count)
+		      int byte_count,
+		      u32 inv_rkey)
 {
 	struct svc_rdma_op_ctxt *ctxt;
 	struct ib_send_wr send_wr;
@@ -489,7 +532,7 @@ static int send_reply(struct svcxprt_rdma *rdma,
 			    ctxt->sge[0].length, DMA_TO_DEVICE);
 	if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr))
 		goto err;
-	atomic_inc(&rdma->sc_dma_used);
+	svc_rdma_count_mappings(rdma, ctxt);
 
 	ctxt->direction = DMA_TO_DEVICE;
 
@@ -505,7 +548,7 @@ static int send_reply(struct svcxprt_rdma *rdma,
 		if (ib_dma_mapping_error(rdma->sc_cm_id->device,
 					 ctxt->sge[sge_no].addr))
 			goto err;
-		atomic_inc(&rdma->sc_dma_used);
+		svc_rdma_count_mappings(rdma, ctxt);
 		ctxt->sge[sge_no].lkey = rdma->sc_pd->local_dma_lkey;
 		ctxt->sge[sge_no].length = sge_bytes;
 	}
@@ -523,23 +566,9 @@ static int send_reply(struct svcxprt_rdma *rdma,
 		ctxt->pages[page_no+1] = rqstp->rq_respages[page_no];
 		ctxt->count++;
 		rqstp->rq_respages[page_no] = NULL;
-		/*
-		 * If there are more pages than SGE, terminate SGE
-		 * list so that svc_rdma_unmap_dma doesn't attempt to
-		 * unmap garbage.
-		 */
-		if (page_no+1 >= sge_no)
-			ctxt->sge[page_no+1].length = 0;
 	}
 	rqstp->rq_next_page = rqstp->rq_respages + 1;
 
-	/* The loop above bumps sc_dma_used for each sge. The
-	 * xdr_buf.tail gets a separate sge, but resides in the
-	 * same page as xdr_buf.head. Don't count it twice.
-	 */
-	if (sge_no > ctxt->count)
-		atomic_dec(&rdma->sc_dma_used);
-
 	if (sge_no > rdma->sc_max_sge) {
 		pr_err("svcrdma: Too many sges (%d)\n", sge_no);
 		goto err;
@@ -549,7 +578,11 @@ static int send_reply(struct svcxprt_rdma *rdma,
 	send_wr.wr_cqe = &ctxt->cqe;
 	send_wr.sg_list = ctxt->sge;
 	send_wr.num_sge = sge_no;
-	send_wr.opcode = IB_WR_SEND;
+	if (inv_rkey) {
+		send_wr.opcode = IB_WR_SEND_WITH_INV;
+		send_wr.ex.invalidate_rkey = inv_rkey;
+	} else
+		send_wr.opcode = IB_WR_SEND;
 	send_wr.send_flags =  IB_SEND_SIGNALED;
 
 	ret = svc_rdma_send(rdma, &send_wr);
@@ -581,6 +614,7 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
 	int inline_bytes;
 	struct page *res_page;
 	struct svc_rdma_req_map *vec;
+	u32 inv_rkey;
 
 	dprintk("svcrdma: sending response for rqstp=%p\n", rqstp);
 
@@ -591,6 +625,10 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
 	wr_ary = svc_rdma_get_write_array(rdma_argp);
 	rp_ary = svc_rdma_get_reply_array(rdma_argp, wr_ary);
 
+	inv_rkey = 0;
+	if (rdma->sc_snd_w_inv)
+		inv_rkey = svc_rdma_get_inv_rkey(rdma_argp, wr_ary, rp_ary);
+
 	/* Build an req vec for the XDR */
 	vec = svc_rdma_get_req_map(rdma);
 	ret = svc_rdma_map_xdr(rdma, &rqstp->rq_res, vec, wr_ary != NULL);
@@ -633,9 +671,9 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
 		goto err1;
 
 	ret = send_reply(rdma, rqstp, res_page, rdma_resp, vec,
-			 inline_bytes);
+			 inline_bytes, inv_rkey);
 	if (ret < 0)
-		goto err1;
+		goto err0;
 
 	svc_rdma_put_req_map(rdma, vec);
 	dprintk("svcrdma: send_reply returns %d\n", ret);
@@ -692,7 +730,7 @@ void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
 		svc_rdma_put_context(ctxt, 1);
 		return;
 	}
-	atomic_inc(&xprt->sc_dma_used);
+	svc_rdma_count_mappings(xprt, ctxt);
 
 	/* Prepare SEND WR */
 	memset(&err_wr, 0, sizeof(err_wr));