net: ena: use xdp_frame in XDP TX flow

Rename the ena_xdp_xmit_buff() function to ena_xdp_xmit_frame() and pass
it an xdp_frame struct instead of xdp_buff.
This change lays the ground for XDP redirect implementation which uses
xdp_frames when 'xmit'ing packets.
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/amazon/ena/ena_netdev.c

@@ -233,18 +233,18 @@ static int ena_xdp_io_poll(struct napi_struct *napi, int budget)
 	return ret;
 }
 
-static int ena_xdp_tx_map_buff(struct ena_ring *xdp_ring,
-			       struct ena_tx_buffer *tx_info,
-			       struct xdp_buff *xdp,
-			       void **push_hdr,
-			       u32 *push_len)
+static int ena_xdp_tx_map_frame(struct ena_ring *xdp_ring,
+				struct ena_tx_buffer *tx_info,
+				struct xdp_frame *xdpf,
+				void **push_hdr,
+				u32 *push_len)
 {
 	struct ena_adapter *adapter = xdp_ring->adapter;
 	struct ena_com_buf *ena_buf;
 	dma_addr_t dma = 0;
 	u32 size;
 
-	tx_info->xdpf = xdp_convert_buff_to_frame(xdp);
+	tx_info->xdpf = xdpf;
 	size = tx_info->xdpf->len;
 	ena_buf = tx_info->bufs;
 
@@ -281,29 +281,31 @@ static int ena_xdp_tx_map_buff(struct ena_ring *xdp_ring,
 	return -EINVAL;
 }
 
-static int ena_xdp_xmit_buff(struct net_device *dev,
-			     struct xdp_buff *xdp,
-			     int qid,
-			     struct ena_rx_buffer *rx_info)
+static int ena_xdp_xmit_frame(struct net_device *dev,
+			      struct xdp_frame *xdpf,
+			      int qid)
 {
 	struct ena_adapter *adapter = netdev_priv(dev);
 	struct ena_com_tx_ctx ena_tx_ctx = {};
 	struct ena_tx_buffer *tx_info;
 	struct ena_ring *xdp_ring;
+	struct page *rx_buff_page;
 	u16 next_to_use, req_id;
 	int rc;
 	void *push_hdr;
 	u32 push_len;
 
+	rx_buff_page = virt_to_page(xdpf->data);
+
 	xdp_ring = &adapter->tx_ring[qid];
 	next_to_use = xdp_ring->next_to_use;
 	req_id = xdp_ring->free_ids[next_to_use];
 	tx_info = &xdp_ring->tx_buffer_info[req_id];
 	tx_info->num_of_bufs = 0;
-	page_ref_inc(rx_info->page);
-	tx_info->xdp_rx_page = rx_info->page;
+	page_ref_inc(rx_buff_page);
+	tx_info->xdp_rx_page = rx_buff_page;
 
-	rc = ena_xdp_tx_map_buff(xdp_ring, tx_info, xdp, &push_hdr, &push_len);
+	rc = ena_xdp_tx_map_frame(xdp_ring, tx_info, xdpf, &push_hdr, &push_len);
 	if (unlikely(rc))
 		goto error_drop_packet;
 
@@ -318,7 +320,7 @@ static int ena_xdp_xmit_buff(struct net_device *dev,
 			     tx_info,
 			     &ena_tx_ctx,
 			     next_to_use,
-			     xdp->data_end - xdp->data);
+			     xdpf->len);
 	if (rc)
 		goto error_unmap_dma;
 	/* trigger the dma engine. ena_com_write_sq_doorbell()
@@ -337,12 +339,11 @@ static int ena_xdp_xmit_buff(struct net_device *dev,
 	return NETDEV_TX_OK;
 }
 
-static int ena_xdp_execute(struct ena_ring *rx_ring,
-			   struct xdp_buff *xdp,
-			   struct ena_rx_buffer *rx_info)
+static int ena_xdp_execute(struct ena_ring *rx_ring, struct xdp_buff *xdp)
 {
 	struct bpf_prog *xdp_prog;
 	u32 verdict = XDP_PASS;
+	struct xdp_frame *xdpf;
 	u64 *xdp_stat;
 
 	rcu_read_lock();
@@ -354,12 +355,16 @@ static int ena_xdp_execute(struct ena_ring *rx_ring,
 	verdict = bpf_prog_run_xdp(xdp_prog, xdp);
 
 	if (verdict == XDP_TX) {
-		ena_xdp_xmit_buff(rx_ring->netdev,
-				  xdp,
-				  rx_ring->qid + rx_ring->adapter->num_io_queues,
-				  rx_info);
+		xdpf = xdp_convert_buff_to_frame(xdp);
+		if (unlikely(!xdpf)) {
+			trace_xdp_exception(rx_ring->netdev, xdp_prog, verdict);
+			xdp_stat = &rx_ring->rx_stats.xdp_aborted;
+		} else {
+			ena_xdp_xmit_frame(rx_ring->netdev, xdpf,
+					   rx_ring->qid + rx_ring->adapter->num_io_queues);
 
-		xdp_stat = &rx_ring->rx_stats.xdp_tx;
+			xdp_stat = &rx_ring->rx_stats.xdp_tx;
+		}
 	} else if (unlikely(verdict == XDP_ABORTED)) {
 		trace_xdp_exception(rx_ring->netdev, xdp_prog, verdict);
 		xdp_stat = &rx_ring->rx_stats.xdp_aborted;
@@ -1521,7 +1526,7 @@ static int ena_xdp_handle_buff(struct ena_ring *rx_ring, struct xdp_buff *xdp)
 	if (unlikely(rx_ring->ena_bufs[0].len > ENA_XDP_MAX_MTU))
 		return XDP_DROP;
 
-	ret = ena_xdp_execute(rx_ring, xdp, rx_info);
+	ret = ena_xdp_execute(rx_ring, xdp);
 
 	/* The xdp program might expand the headers */
 	if (ret == XDP_PASS) {
@@ -1600,7 +1605,7 @@ static int ena_clean_rx_irq(struct ena_ring *rx_ring, struct napi_struct *napi,
 		if (unlikely(!skb)) {
 			/* The page might not actually be freed here since the
 			 * page reference count is incremented in
-			 * ena_xdp_xmit_buff(), and it will be decreased only
+			 * ena_xdp_xmit_frame(), and it will be decreased only
 			 * when send completion was received from the device
 			 */
 			if (xdp_verdict == XDP_TX)