Merge branch 'ena-driver-xdp-bug-fixes'

David Arinzon says:

====================
ENA driver XDP bug fixes

This patchset contains multiple XDP-related bug fixes
in the ENA driver.
====================

Link: https://lore.kernel.org/r/20231211062801.27891-1-darinzon@amazon.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

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

@@ -328,9 +328,6 @@ static int ena_com_create_and_store_tx_meta_desc(struct ena_com_io_sq *io_sq,
 	 * compare it to the stored version, just create the meta
 	 */
 	if (io_sq->disable_meta_caching) {
-		if (unlikely(!ena_tx_ctx->meta_valid))
-			return -EINVAL;
-
 		*have_meta = true;
 		return ena_com_create_meta(io_sq, ena_meta);
 	}

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

@@ -74,6 +74,8 @@ static void ena_unmap_tx_buff(struct ena_ring *tx_ring,
 			      struct ena_tx_buffer *tx_info);
 static int ena_create_io_tx_queues_in_range(struct ena_adapter *adapter,
 					    int first_index, int count);
+static void ena_free_all_io_tx_resources_in_range(struct ena_adapter *adapter,
+						  int first_index, int count);
 
 /* Increase a stat by cnt while holding syncp seqlock on 32bit machines */
 static void ena_increase_stat(u64 *statp, u64 cnt,
@@ -457,23 +459,22 @@ static void ena_init_all_xdp_queues(struct ena_adapter *adapter)
 
 static int ena_setup_and_create_all_xdp_queues(struct ena_adapter *adapter)
 {
+	u32 xdp_first_ring = adapter->xdp_first_ring;
+	u32 xdp_num_queues = adapter->xdp_num_queues;
 	int rc = 0;
 
-	rc = ena_setup_tx_resources_in_range(adapter, adapter->xdp_first_ring,
-					     adapter->xdp_num_queues);
+	rc = ena_setup_tx_resources_in_range(adapter, xdp_first_ring, xdp_num_queues);
 	if (rc)
 		goto setup_err;
 
-	rc = ena_create_io_tx_queues_in_range(adapter,
-					      adapter->xdp_first_ring,
-					      adapter->xdp_num_queues);
+	rc = ena_create_io_tx_queues_in_range(adapter, xdp_first_ring, xdp_num_queues);
 	if (rc)
 		goto create_err;
 
 	return 0;
 
 create_err:
-	ena_free_all_io_tx_resources(adapter);
+	ena_free_all_io_tx_resources_in_range(adapter, xdp_first_ring, xdp_num_queues);
 setup_err:
 	return rc;
 }
@@ -1492,11 +1493,6 @@ static struct sk_buff *ena_rx_skb(struct ena_ring *rx_ring,
 		if (unlikely(!skb))
 			return NULL;
 
-		/* sync this buffer for CPU use */
-		dma_sync_single_for_cpu(rx_ring->dev,
-					dma_unmap_addr(&rx_info->ena_buf, paddr) + pkt_offset,
-					len,
-					DMA_FROM_DEVICE);
 		skb_copy_to_linear_data(skb, buf_addr + buf_offset, len);
 		dma_sync_single_for_device(rx_ring->dev,
 					   dma_unmap_addr(&rx_info->ena_buf, paddr) + pkt_offset,
@@ -1515,17 +1511,10 @@ static struct sk_buff *ena_rx_skb(struct ena_ring *rx_ring,
 
 	buf_len = SKB_DATA_ALIGN(len + buf_offset + tailroom);
 
-	pre_reuse_paddr = dma_unmap_addr(&rx_info->ena_buf, paddr);
-
 	/* If XDP isn't loaded try to reuse part of the RX buffer */
 	reuse_rx_buf_page = !is_xdp_loaded &&
 			    ena_try_rx_buf_page_reuse(rx_info, buf_len, len, pkt_offset);
 
-	dma_sync_single_for_cpu(rx_ring->dev,
-				pre_reuse_paddr + pkt_offset,
-				len,
-				DMA_FROM_DEVICE);
-
 	if (!reuse_rx_buf_page)
 		ena_unmap_rx_buff_attrs(rx_ring, rx_info, DMA_ATTR_SKIP_CPU_SYNC);
 
@@ -1671,20 +1660,23 @@ static void ena_set_rx_hash(struct ena_ring *rx_ring,
 	}
 }
 
-static int ena_xdp_handle_buff(struct ena_ring *rx_ring, struct xdp_buff *xdp)
+static int ena_xdp_handle_buff(struct ena_ring *rx_ring, struct xdp_buff *xdp, u16 num_descs)
 {
 	struct ena_rx_buffer *rx_info;
 	int ret;
 
+	/* XDP multi-buffer packets not supported */
+	if (unlikely(num_descs > 1)) {
+		netdev_err_once(rx_ring->adapter->netdev,
+				"xdp: dropped unsupported multi-buffer packets\n");
+		ena_increase_stat(&rx_ring->rx_stats.xdp_drop, 1, &rx_ring->syncp);
+		return ENA_XDP_DROP;
+	}
+
 	rx_info = &rx_ring->rx_buffer_info[rx_ring->ena_bufs[0].req_id];
 	xdp_prepare_buff(xdp, page_address(rx_info->page),
 			 rx_info->buf_offset,
 			 rx_ring->ena_bufs[0].len, false);
-	/* If for some reason we received a bigger packet than
-	 * we expect, then we simply drop it
-	 */
-	if (unlikely(rx_ring->ena_bufs[0].len > ENA_XDP_MAX_MTU))
-		return ENA_XDP_DROP;
 
 	ret = ena_xdp_execute(rx_ring, xdp);
 
@@ -1719,6 +1711,7 @@ static int ena_clean_rx_irq(struct ena_ring *rx_ring, struct napi_struct *napi,
 	int xdp_flags = 0;
 	int total_len = 0;
 	int xdp_verdict;
+	u8 pkt_offset;
 	int rc = 0;
 	int i;
 
@@ -1745,15 +1738,21 @@ static int ena_clean_rx_irq(struct ena_ring *rx_ring, struct napi_struct *napi,
 
 		/* First descriptor might have an offset set by the device */
 		rx_info = &rx_ring->rx_buffer_info[rx_ring->ena_bufs[0].req_id];
-		rx_info->buf_offset += ena_rx_ctx.pkt_offset;
+		pkt_offset = ena_rx_ctx.pkt_offset;
+		rx_info->buf_offset += pkt_offset;
 
 		netif_dbg(rx_ring->adapter, rx_status, rx_ring->netdev,
 			  "rx_poll: q %d got packet from ena. descs #: %d l3 proto %d l4 proto %d hash: %x\n",
 			  rx_ring->qid, ena_rx_ctx.descs, ena_rx_ctx.l3_proto,
 			  ena_rx_ctx.l4_proto, ena_rx_ctx.hash);
 
+		dma_sync_single_for_cpu(rx_ring->dev,
+					dma_unmap_addr(&rx_info->ena_buf, paddr) + pkt_offset,
+					rx_ring->ena_bufs[0].len,
+					DMA_FROM_DEVICE);
+
 		if (ena_xdp_present_ring(rx_ring))
-			xdp_verdict = ena_xdp_handle_buff(rx_ring, &xdp);
+			xdp_verdict = ena_xdp_handle_buff(rx_ring, &xdp, ena_rx_ctx.descs);
 
 		/* allocate skb and fill it */
 		if (xdp_verdict == ENA_XDP_PASS)
@@ -1777,7 +1776,7 @@ static int ena_clean_rx_irq(struct ena_ring *rx_ring, struct napi_struct *napi,
 				if (xdp_verdict & ENA_XDP_FORWARDED) {
 					ena_unmap_rx_buff_attrs(rx_ring,
 								&rx_ring->rx_buffer_info[req_id],
-								0);
+								DMA_ATTR_SKIP_CPU_SYNC);
 					rx_ring->rx_buffer_info[req_id].page = NULL;
 				}
 			}