Reserve XDP_PACKET_HEADROOM bytes in Rx buffers to allow XDP
programs to increase frame header size.
Signed-off-by: Ioana Radulescu <ruxandra.radule...@nxp.com>
---
drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 43 ++++++++++++++++++++++--
1 file changed, 40 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
index 5340ac9..5be3008 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
@@ -216,11 +216,15 @@ static u32 run_xdp(struct dpaa2_eth_priv *priv,
xdp.data = vaddr + dpaa2_fd_get_offset(fd);
xdp.data_end = xdp.data + dpaa2_fd_get_len(fd);
- xdp.data_hard_start = xdp.data;
+ xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
xdp_set_data_meta_invalid(&xdp);
xdp_act = bpf_prog_run_xdp(xdp_prog, &xdp);
+ /* xdp.data pointer may have changed */
+ dpaa2_fd_set_offset(fd, xdp.data - vaddr);
+ dpaa2_fd_set_len(fd, xdp.data_end - xdp.data);
+
switch (xdp_act) {
case XDP_PASS:
break;
@@ -1480,7 +1484,7 @@ static bool xdp_mtu_valid(struct dpaa2_eth_priv *priv,
int mtu)
mfl = DPAA2_ETH_L2_MAX_FRM(mtu);
linear_mfl = DPAA2_ETH_RX_BUF_SIZE - DPAA2_ETH_RX_HWA_SIZE -
- dpaa2_eth_rx_head_room(priv);
+ dpaa2_eth_rx_head_room(priv) - XDP_PACKET_HEADROOM;
return (mfl <= linear_mfl);
}
@@ -1528,6 +1532,32 @@ static int dpaa2_eth_change_mtu(struct net_device *dev,
int new_mtu)
return 0;
}
+static int update_rx_buffer_headroom(struct dpaa2_eth_priv *priv, bool has_xdp)
+{
+ struct dpni_buffer_layout buf_layout = {0};
+ int err;
+
+ err = dpni_get_buffer_layout(priv->mc_io, 0, priv->mc_token,
+ DPNI_QUEUE_RX, &buf_layout);
+ if (err) {
+ netdev_err(priv->net_dev, "dpni_get_buffer_layout failed\n");
+ return err;
+ }
+
+ /* Reserve extra headroom for XDP header size changes */
+ buf_layout.data_head_room = dpaa2_eth_rx_head_room(priv) +
+ (has_xdp ? XDP_PACKET_HEADROOM : 0);
+ buf_layout.options = DPNI_BUF_LAYOUT_OPT_DATA_HEAD_ROOM;
+ err = dpni_set_buffer_layout(priv->mc_io, 0, priv->mc_token,
+ DPNI_QUEUE_RX, &buf_layout);
+ if (err) {
+ netdev_err(priv->net_dev, "dpni_set_buffer_layout failed\n");
+ return err;
+ }
+
+ return 0;
+}
+
static int setup_xdp(struct net_device *dev, struct bpf_prog *prog)
{
struct dpaa2_eth_priv *priv = netdev_priv(dev);
@@ -1553,11 +1583,18 @@ static int setup_xdp(struct net_device *dev, struct
bpf_prog *prog)
if (up)
dpaa2_eth_stop(dev);
- /* While in xdp mode, enforce a maximum Rx frame size based on MTU */
+ /* While in xdp mode, enforce a maximum Rx frame size based on MTU.
+ * Also, when switching between xdp/non-xdp modes we need to reconfigure
+ * our Rx buffer layout. Buffer pool was drained on dpaa2_eth_stop,
+ * so we are sure no old format buffers will be used from now on.
+ */
if (update_settings) {
err = set_rx_mfl(priv, dev->mtu, !!prog);
if (err)
goto out_err;
+ err = update_rx_buffer_headroom(priv, !!prog);
+ if (err)
+ goto out_err;
}
old = xchg(&priv->xdp_prog, prog);
--
2.7.4
