tsnep: Remove FCS for XDP data path

[ Upstream commit 50bad6f797d4d501c5ef416a6f92e1912ab5aa8b ]

The RX data buffer includes the FCS. The FCS is already stripped for the
normal data path. But for the XDP data path the FCS is included and
acts like additional/useless data.

Remove the FCS from the RX data buffer also for XDP.

Fixes: 65b28c810035 ("tsnep: Add XDP RX support")
Fixes: 3fc2333933fd ("tsnep: Add XDP socket zero-copy RX support")
Signed-off-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/engleder/tsnep_main.c b/drivers/net/ethernet/engleder/tsnep_main.c
index df40c720e7b23d517433743efb883edb8f8d4cf4..456e0336f3f6640b4a0f1b298cf2310824f08a1e 100644 (file)
--- a/drivers/net/ethernet/engleder/tsnep_main.c
+++ b/drivers/net/ethernet/engleder/tsnep_main.c
@@ -1485,7 +1485,7 @@ static int tsnep_rx_poll(struct tsnep_rx *rx, struct napi_struct *napi,
 
                        xdp_prepare_buff(&xdp, page_address(entry->page),
                                         XDP_PACKET_HEADROOM + TSNEP_RX_INLINE_METADATA_SIZE,
-                                        length, false);
+                                        length - ETH_FCS_LEN, false);
 
                        consume = tsnep_xdp_run_prog(rx, prog, &xdp,
                                                     &xdp_status, tx_nq, tx);
@@ -1568,7 +1568,7 @@ static int tsnep_rx_poll_zc(struct tsnep_rx *rx, struct napi_struct *napi,
                prefetch(entry->xdp->data);
                length = __le32_to_cpu(entry->desc_wb->properties) &
                         TSNEP_DESC_LENGTH_MASK;
-               xsk_buff_set_size(entry->xdp, length);
+               xsk_buff_set_size(entry->xdp, length - ETH_FCS_LEN);
                xsk_buff_dma_sync_for_cpu(entry->xdp, rx->xsk_pool);
 
                /* RX metadata with timestamps is in front of actual data,