net: lan966x: Add XDP_PACKET_HEADROOM

Update the page_pool params to allocate XDP_PACKET_HEADROOM space as
headroom for all received frames.
This is needed for when the XDP_TX and XDP_REDIRECT are implemented.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
index 5fbbd47..3055124 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c
@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0+
 
+#include <linux/bpf.h>
+
 #include "lan966x_main.h"
 
 static int lan966x_fdma_channel_active(struct lan966x *lan966x)
@@ -16,7 +18,7 @@ static struct page *lan966x_fdma_rx_alloc_page(struct lan966x_rx *rx,
        if (unlikely(!page))
                return NULL;
 
-       db->dataptr = page_pool_get_dma_addr(page);
+       db->dataptr = page_pool_get_dma_addr(page) + XDP_PACKET_HEADROOM;
 
        return page;
 }
@@ -72,7 +74,7 @@ static int lan966x_fdma_rx_alloc_page_pool(struct lan966x_rx *rx)
                .nid = NUMA_NO_NODE,
                .dev = lan966x->dev,
                .dma_dir = DMA_FROM_DEVICE,
-               .offset = 0,
+               .offset = XDP_PACKET_HEADROOM,
                .max_len = rx->max_mtu -
                           SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
        };
@@ -432,11 +434,13 @@ static int lan966x_fdma_rx_check_frame(struct lan966x_rx *rx, u64 *src_port)
        if (unlikely(!page))
                return FDMA_ERROR;
 
-       dma_sync_single_for_cpu(lan966x->dev, (dma_addr_t)db->dataptr,
+       dma_sync_single_for_cpu(lan966x->dev,
+                               (dma_addr_t)db->dataptr + XDP_PACKET_HEADROOM,
                                FDMA_DCB_STATUS_BLOCKL(db->status),
                                DMA_FROM_DEVICE);
 
-       lan966x_ifh_get_src_port(page_address(page), src_port);
+       lan966x_ifh_get_src_port(page_address(page) + XDP_PACKET_HEADROOM,
+                                src_port);
        if (WARN_ON(*src_port >= lan966x->num_phys_ports))
                return FDMA_ERROR;
 
@@ -466,6 +470,7 @@ static struct sk_buff *lan966x_fdma_rx_get_frame(struct lan966x_rx *rx,
 
        skb_mark_for_recycle(skb);
 
+       skb_reserve(skb, XDP_PACKET_HEADROOM);
        skb_put(skb, FDMA_DCB_STATUS_BLOCKL(db->status));
 
        lan966x_ifh_get_timestamp(skb->data, &timestamp);
@@ -786,7 +791,8 @@ static int lan966x_fdma_get_max_frame(struct lan966x *lan966x)
        return lan966x_fdma_get_max_mtu(lan966x) +
               IFH_LEN_BYTES +
               SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
-              VLAN_HLEN * 2;
+              VLAN_HLEN * 2 +
+              XDP_PACKET_HEADROOM;
 }
 
 int lan966x_fdma_change_mtu(struct lan966x *lan966x)

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
index e77d9f2..8ebde1e 100644 (file)
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c
@@ -44,7 +44,8 @@ int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
 
        xdp_init_buff(&xdp, PAGE_SIZE << lan966x->rx.page_order,
                      &port->xdp_rxq);
-       xdp_prepare_buff(&xdp, page_address(page), IFH_LEN_BYTES,
+       xdp_prepare_buff(&xdp, page_address(page),
+                        IFH_LEN_BYTES + XDP_PACKET_HEADROOM,
                         data_len - IFH_LEN_BYTES, false);
        act = bpf_prog_run_xdp(xdp_prog, &xdp);
        switch (act) {