[PATCH for-next v2 16/18] RDMA/rxe: Extend send/write_data_in() for frags

[Bob Pearson <rpearsonhpe@gmail.com>]

Extend send_data_in() and write_data_in() in rxe_resp.c to
support fragmented received skbs.

This is in preparation for using fragmented skbs.

Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
---
 drivers/infiniband/sw/rxe/rxe_resp.c | 103 +++++++++++++++++----------
 1 file changed, 65 insertions(+), 38 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c
index 905e19ee9ca5..419e8af235aa 100644
--- a/drivers/infiniband/sw/rxe/rxe_resp.c
+++ b/drivers/infiniband/sw/rxe/rxe_resp.c
@@ -518,45 +518,89 @@ static enum resp_states check_rkey(struct rxe_qp *qp,
 	return state;
 }
 
-static enum resp_states send_data_in(struct rxe_qp *qp, void *data_addr,
-				     int data_len)
+/**
+ * rxe_send_data_in() - Copy payload data into receive buffer
+ * @qp: The queue pair
+ * @pkt: Request packet info
+ *
+ * Copy the packet payload into the receive buffer at the current offset.
+ * If a UD message also copy the IP header into the receive buffer.
+ *
+ * Returns: 0 if successful else an error resp_states value.
+ */
+static enum resp_states rxe_send_data_in(struct rxe_qp *qp,
+					 struct rxe_pkt_info *pkt)
 {
-	struct sk_buff *skb = NULL;
+	struct sk_buff *skb = PKT_TO_SKB(pkt);
+	int nr_frags = skb_shinfo(skb)->nr_frags;
+	u8 *data_addr = payload_addr(pkt);
+	int data_len = payload_size(pkt);
+	union rdma_network_hdr hdr;
+	enum rxe_mr_copy_op op;
 	int skb_offset = 0;
 	int err;
 
+	/* Per IBA for UD packets copy the IP header into the receive buffer */
+	if (qp_type(qp) == IB_QPT_UD || qp_type(qp) == IB_QPT_GSI) {
+		if (skb->protocol == htons(ETH_P_IP)) {
+			memset(&hdr.reserved, 0, sizeof(hdr.reserved));
+			memcpy(&hdr.roce4grh, ip_hdr(skb), sizeof(hdr.roce4grh));
+		} else {
+			memcpy(&hdr.ibgrh, ipv6_hdr(skb), sizeof(hdr));
+		}
+		err = rxe_copy_dma_data(skb, qp->pd, IB_ACCESS_LOCAL_WRITE,
+					&qp->resp.wqe->dma, &hdr, skb_offset,
+					sizeof(hdr), RXE_COPY_TO_MR);
+		if (err)
+			goto err_out;
+	}
+
+	op = nr_frags ? RXE_FRAG_TO_MR : RXE_COPY_TO_MR;
+	skb_offset = data_addr - skb_transport_header(skb);
 	err = rxe_copy_dma_data(skb, qp->pd, IB_ACCESS_LOCAL_WRITE,
 				&qp->resp.wqe->dma, data_addr,
-				skb_offset, data_len, RXE_COPY_TO_MR);
-	if (unlikely(err))
-		return (err == -ENOSPC) ? RESPST_ERR_LENGTH
-					: RESPST_ERR_MALFORMED_WQE;
+				skb_offset, data_len, op);
+	if (err)
+		goto err_out;
 
 	return RESPST_NONE;
+
+err_out:
+	return (err == -ENOSPC) ? RESPST_ERR_LENGTH
+				: RESPST_ERR_MALFORMED_WQE;
 }
 
-static enum resp_states write_data_in(struct rxe_qp *qp,
-				      struct rxe_pkt_info *pkt)
+/**
+ * rxe_write_data_in() - Copy payload data to iova
+ * @qp: The queue pair
+ * @pkt: Request packet info
+ *
+ * Copy the packet payload to current iova and update iova.
+ *
+ * Returns: 0 if successful else an error resp_states value.
+ */
+static enum resp_states rxe_write_data_in(struct rxe_qp *qp,
+					  struct rxe_pkt_info *pkt)
 {
 	struct sk_buff *skb = PKT_TO_SKB(pkt);
-	enum resp_states rc = RESPST_NONE;
+	int nr_frags = skb_shinfo(skb)->nr_frags;
+	u8 *data_addr = payload_addr(pkt);
 	int data_len = payload_size(pkt);
+	enum rxe_mr_copy_op op;
+	int skb_offset;
 	int err;
-	int skb_offset = 0;
 
+	op = nr_frags ? RXE_FRAG_TO_MR : RXE_COPY_TO_MR;
+	skb_offset = data_addr - skb_transport_header(skb);
 	err = rxe_copy_mr_data(skb, qp->resp.mr, qp->resp.va + qp->resp.offset,
-			  payload_addr(pkt), skb_offset, data_len,
-			  RXE_COPY_TO_MR);
-	if (err) {
-		rc = RESPST_ERR_RKEY_VIOLATION;
-		goto out;
-	}
+			  data_addr, skb_offset, data_len, op);
+	if (err)
+		return RESPST_ERR_RKEY_VIOLATION;
 
 	qp->resp.va += data_len;
 	qp->resp.resid -= data_len;
 
-out:
-	return rc;
+	return RESPST_NONE;
 }
 
 static struct resp_res *rxe_prepare_res(struct rxe_qp *qp,
@@ -884,30 +928,13 @@ static int invalidate_rkey(struct rxe_qp *qp, u32 rkey)
 static enum resp_states execute(struct rxe_qp *qp, struct rxe_pkt_info *pkt)
 {
 	enum resp_states err;
-	struct sk_buff *skb = PKT_TO_SKB(pkt);
-	union rdma_network_hdr hdr;
 
 	if (pkt->mask & RXE_SEND_MASK) {
-		if (qp_type(qp) == IB_QPT_UD ||
-		    qp_type(qp) == IB_QPT_GSI) {
-			if (skb->protocol == htons(ETH_P_IP)) {
-				memset(&hdr.reserved, 0,
-						sizeof(hdr.reserved));
-				memcpy(&hdr.roce4grh, ip_hdr(skb),
-						sizeof(hdr.roce4grh));
-				err = send_data_in(qp, &hdr, sizeof(hdr));
-			} else {
-				err = send_data_in(qp, ipv6_hdr(skb),
-						sizeof(hdr));
-			}
-			if (err)
-				return err;
-		}
-		err = send_data_in(qp, payload_addr(pkt), payload_size(pkt));
+		err = rxe_send_data_in(qp, pkt);
 		if (err)
 			return err;
 	} else if (pkt->mask & RXE_WRITE_MASK) {
-		err = write_data_in(qp, pkt);
+		err = rxe_write_data_in(qp, pkt);
 		if (err)
 			return err;
 	} else if (pkt->mask & RXE_READ_MASK) {
-- 
2.34.1