From: Charles McLachlan <cmclachlan@solarflare.com>
Date: Fri, 20 Dec 2019 16:27:10 +0000
Subject: sfc: Include XDP packet headroom in buffer step size.
Patch-mainline: v5.5-rc3
Git-commit: 11a14dc8d7a76d3117896b975c536f1372f2a7c4
References: jsc#SLE-8314
Correct a mismatch between rx_page_buf_step and the actual step size
used when filling buffer pages.
This patch fixes the page overrun that occured when the MTU was set to
anything bigger than 1692.
Fixes: 3990a8fffbda ("sfc: allocate channels for XDP tx queues")
Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/sfc/rx.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
--- a/drivers/net/ethernet/sfc/rx.c
+++ b/drivers/net/ethernet/sfc/rx.c
@@ -96,11 +96,12 @@ static inline void efx_sync_rx_buffer(st
void efx_rx_config_page_split(struct efx_nic *efx)
{
- efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align,
+ efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align +
+ XDP_PACKET_HEADROOM,
EFX_RX_BUF_ALIGNMENT);
efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
((PAGE_SIZE - sizeof(struct efx_rx_page_state)) /
- (efx->rx_page_buf_step + XDP_PACKET_HEADROOM));
+ efx->rx_page_buf_step);
efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) /
efx->rx_bufs_per_page;
efx->rx_pages_per_batch = DIV_ROUND_UP(EFX_RX_PREFERRED_BATCH,
@@ -190,14 +191,13 @@ static int efx_init_rx_buffers(struct ef
page_offset = sizeof(struct efx_rx_page_state);
do {
- page_offset += XDP_PACKET_HEADROOM;
- dma_addr += XDP_PACKET_HEADROOM;
-
index = rx_queue->added_count & rx_queue->ptr_mask;
rx_buf = efx_rx_buffer(rx_queue, index);
- rx_buf->dma_addr = dma_addr + efx->rx_ip_align;
+ rx_buf->dma_addr = dma_addr + efx->rx_ip_align +
+ XDP_PACKET_HEADROOM;
rx_buf->page = page;
- rx_buf->page_offset = page_offset + efx->rx_ip_align;
+ rx_buf->page_offset = page_offset + efx->rx_ip_align +
+ XDP_PACKET_HEADROOM;
rx_buf->len = efx->rx_dma_len;
rx_buf->flags = 0;
++rx_queue->added_count;