realtek: eth: move tx skb into driver-only structure

The TX path stores the skb information in the coherent part. This
is only needed by the driver. Move it to its proper location.

Link: https://github.com/openwrt/openwrt/pull/24346
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>

diff --git a/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c b/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c
index 78b66ec33ce4185dd9bc9130ba0d70fc9898e9ab..aec96764950e4ffbb2b138e6fb5c2a90edee1e45 100644 (file)
--- a/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c
+++ b/target/linux/realtek/files-6.18/drivers/net/ethernet/rtl838x_eth.c
@@ -63,8 +63,6 @@ struct rteth_packet {
        u16                     offset:15;
        u16                     len;
        u16                     cpu_tag[10];
-       /* software mangement and data part */
-       struct sk_buff          *skb;
 } __packed __aligned(1);
 
 /* SOC/driver shared coherent ring descriptors */
@@ -92,6 +90,7 @@ struct rteth_rx_info {
 
 struct rteth_tx_info {
        int                     slot;
+       struct sk_buff          *skb[RTETH_TX_RING_SIZE];
 };
 
 struct n_event {
@@ -644,17 +643,19 @@ static void rteth_931x_hw_en_rxtx(struct rteth_ctrl *ctrl)
 
 static void rteth_free_tx_buffers(struct rteth_ctrl *ctrl)
 {
-       struct rteth_packet *packet;
+       struct rteth_tx_info *tx_info;
 
        for (int r = 0; r < RTETH_TX_RINGS; r++) {
+               tx_info = &ctrl->tx_info[r];
                for (int i = 0; i < RTETH_TX_RING_SIZE; i++) {
-                       packet = &ctrl->tx_data[r].packet[i];
-                       if (!packet->skb)
+                       dma_addr_t dma = ctrl->tx_data[r].packet[i].dma;
+
+                       if (!tx_info->skb[i])
                                continue;
 
-                       dma_unmap_single(&ctrl->pdev->dev, packet->dma,
-                                        packet->skb->len, DMA_TO_DEVICE);
-                       rteth_free_skb(&packet->skb);
+                       dma_unmap_single(&ctrl->pdev->dev, dma,
+                                        tx_info->skb[i]->len, DMA_TO_DEVICE);
+                       rteth_free_skb(&tx_info->skb[i]);
                }
        }
 }
@@ -726,7 +727,7 @@ static int rteth_setup_ring_buffer(struct rteth_ctrl *ctrl)
 
        for (int r = 0; r < RTETH_TX_RINGS; r++) {
                for (int i = 0; i < RTETH_TX_RING_SIZE; i++) {
-                       ctrl->tx_data[r].packet[i].skb = NULL;
+                       ctrl->tx_info[r].skb[i] = NULL;
                        ctrl->tx_data[r].ring[i] = ctrl->tx_dma +
                                                   sizeof(struct rteth_tx_data) * r +
                                                   offsetof(struct rteth_tx_data, packet) +
@@ -1057,6 +1058,7 @@ static int rteth_start_xmit(struct sk_buff *skb, struct net_device *dev)
        int port, val, slot, len = skb->len, ring = skb_get_queue_mapping(skb);
        struct rteth_ctrl *ctrl = netdev_priv(dev);
        struct rteth_packet *packet;
+       struct sk_buff **packet_skb;
        dma_addr_t packet_dma;
 
        port = rteth_get_dsa_port(skb, dev);
@@ -1074,6 +1076,7 @@ static int rteth_start_xmit(struct sk_buff *skb, struct net_device *dev)
        slot = ctrl->tx_info[ring].slot;
        packet = &ctrl->tx_data[ring].packet[slot];
        packet_dma = ctrl->tx_data[ring].ring[slot];
+       packet_skb = &ctrl->tx_info[ring].skb[slot];
 
        if (unlikely(packet_dma & RING_OWN_HW)) {
                netif_stop_subqueue(dev, ring);
@@ -1083,17 +1086,17 @@ static int rteth_start_xmit(struct sk_buff *skb, struct net_device *dev)
                return NETDEV_TX_BUSY;
        }
 
-       if (likely(packet->skb)) {
+       if (likely(*packet_skb)) {
                /* cleanup old data of this slot */
-               dma_unmap_single(&ctrl->pdev->dev, packet->dma, packet->skb->len, DMA_TO_DEVICE);
-               dev_consume_skb_any(packet->skb);
+               dma_unmap_single(&ctrl->pdev->dev, packet->dma, (*packet_skb)->len, DMA_TO_DEVICE);
+               dev_consume_skb_any(*packet_skb);
        }
 
+       *packet_skb = skb;
        packet->len = len;
-       packet->skb = skb;
        packet->dma = dma_map_single(&ctrl->pdev->dev, skb->data, len, DMA_TO_DEVICE);
        if (unlikely(dma_mapping_error(&ctrl->pdev->dev, packet->dma))) {
-               dev->stats.tx_errors += rteth_free_skb(&packet->skb);
+               dev->stats.tx_errors += rteth_free_skb(packet_skb);
                return NETDEV_TX_OK;
        }