mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-19 21:58:04 +00:00
b704c537cf
This is an automatically generated commit which aids following Kernel patch history, as git will see the move and copy as a rename thus defeating the purpose. For the original discussion see: https://lists.openwrt.org/pipermail/openwrt-devel/2023-October/041673.html Signed-off-by: Martin Schiller <ms@dev.tdt.de>
123 lines
4.0 KiB
Diff
123 lines
4.0 KiB
Diff
From 1488fc204568f707fe2a42a913788c00a95af30e Mon Sep 17 00:00:00 2001
|
|
From: Aleksander Jan Bajkowski <olek2@wp.pl>
|
|
Date: Fri, 17 Dec 2021 01:07:40 +0100
|
|
Subject: [PATCH] net: lantiq_xrx200: increase buffer reservation
|
|
|
|
If the user sets a lower mtu on the CPU port than on the switch,
|
|
then DMA inserts a few more bytes into the buffer than expected.
|
|
In the worst case, it may exceed the size of the buffer. The
|
|
experiments showed that the buffer should be a multiple of the
|
|
burst length value. This patch rounds the length of the rx buffer
|
|
upwards and fixes this bug. The reservation of FCS space in the
|
|
buffer has been removed as PMAC strips the FCS.
|
|
|
|
Fixes: 998ac358019e ("net: lantiq: add support for jumbo frames")
|
|
Reported-by: Thomas Nixon <tom@tomn.co.uk>
|
|
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
|
|
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
---
|
|
drivers/net/ethernet/lantiq_xrx200.c | 34 ++++++++++++++++++++--------
|
|
1 file changed, 24 insertions(+), 10 deletions(-)
|
|
|
|
--- a/drivers/net/ethernet/lantiq_xrx200.c
|
|
+++ b/drivers/net/ethernet/lantiq_xrx200.c
|
|
@@ -70,6 +70,8 @@ struct xrx200_priv {
|
|
struct xrx200_chan chan_tx;
|
|
struct xrx200_chan chan_rx;
|
|
|
|
+ u16 rx_buf_size;
|
|
+
|
|
struct net_device *net_dev;
|
|
struct device *dev;
|
|
|
|
@@ -96,6 +98,16 @@ static void xrx200_pmac_mask(struct xrx2
|
|
xrx200_pmac_w32(priv, val, offset);
|
|
}
|
|
|
|
+static int xrx200_max_frame_len(int mtu)
|
|
+{
|
|
+ return VLAN_ETH_HLEN + mtu;
|
|
+}
|
|
+
|
|
+static int xrx200_buffer_size(int mtu)
|
|
+{
|
|
+ return round_up(xrx200_max_frame_len(mtu), 4 * XRX200_DMA_BURST_LEN);
|
|
+}
|
|
+
|
|
/* drop all the packets from the DMA ring */
|
|
static void xrx200_flush_dma(struct xrx200_chan *ch)
|
|
{
|
|
@@ -108,8 +120,7 @@ static void xrx200_flush_dma(struct xrx2
|
|
break;
|
|
|
|
desc->ctl = LTQ_DMA_OWN | LTQ_DMA_RX_OFFSET(NET_IP_ALIGN) |
|
|
- (ch->priv->net_dev->mtu + VLAN_ETH_HLEN +
|
|
- ETH_FCS_LEN);
|
|
+ ch->priv->rx_buf_size;
|
|
ch->dma.desc++;
|
|
ch->dma.desc %= LTQ_DESC_NUM;
|
|
}
|
|
@@ -157,21 +168,21 @@ static int xrx200_close(struct net_devic
|
|
|
|
static int xrx200_alloc_skb(struct xrx200_chan *ch)
|
|
{
|
|
- int len = ch->priv->net_dev->mtu + VLAN_ETH_HLEN + ETH_FCS_LEN;
|
|
struct sk_buff *skb = ch->skb[ch->dma.desc];
|
|
+ struct xrx200_priv *priv = ch->priv;
|
|
dma_addr_t mapping;
|
|
int ret = 0;
|
|
|
|
- ch->skb[ch->dma.desc] = netdev_alloc_skb_ip_align(ch->priv->net_dev,
|
|
- len);
|
|
+ ch->skb[ch->dma.desc] = netdev_alloc_skb_ip_align(priv->net_dev,
|
|
+ priv->rx_buf_size);
|
|
if (!ch->skb[ch->dma.desc]) {
|
|
ret = -ENOMEM;
|
|
goto skip;
|
|
}
|
|
|
|
- mapping = dma_map_single(ch->priv->dev, ch->skb[ch->dma.desc]->data,
|
|
- len, DMA_FROM_DEVICE);
|
|
- if (unlikely(dma_mapping_error(ch->priv->dev, mapping))) {
|
|
+ mapping = dma_map_single(priv->dev, ch->skb[ch->dma.desc]->data,
|
|
+ priv->rx_buf_size, DMA_FROM_DEVICE);
|
|
+ if (unlikely(dma_mapping_error(priv->dev, mapping))) {
|
|
dev_kfree_skb_any(ch->skb[ch->dma.desc]);
|
|
ch->skb[ch->dma.desc] = skb;
|
|
ret = -ENOMEM;
|
|
@@ -183,7 +194,7 @@ static int xrx200_alloc_skb(struct xrx20
|
|
wmb();
|
|
skip:
|
|
ch->dma.desc_base[ch->dma.desc].ctl =
|
|
- LTQ_DMA_OWN | LTQ_DMA_RX_OFFSET(NET_IP_ALIGN) | len;
|
|
+ LTQ_DMA_OWN | LTQ_DMA_RX_OFFSET(NET_IP_ALIGN) | priv->rx_buf_size;
|
|
|
|
return ret;
|
|
}
|
|
@@ -355,6 +366,7 @@ xrx200_change_mtu(struct net_device *net
|
|
int ret = 0;
|
|
|
|
net_dev->mtu = new_mtu;
|
|
+ priv->rx_buf_size = xrx200_buffer_size(new_mtu);
|
|
|
|
if (new_mtu <= old_mtu)
|
|
return ret;
|
|
@@ -374,6 +386,7 @@ xrx200_change_mtu(struct net_device *net
|
|
ret = xrx200_alloc_skb(ch_rx);
|
|
if (ret) {
|
|
net_dev->mtu = old_mtu;
|
|
+ priv->rx_buf_size = xrx200_buffer_size(old_mtu);
|
|
break;
|
|
}
|
|
dev_kfree_skb_any(skb);
|
|
@@ -503,7 +516,8 @@ static int xrx200_probe(struct platform_
|
|
net_dev->netdev_ops = &xrx200_netdev_ops;
|
|
SET_NETDEV_DEV(net_dev, dev);
|
|
net_dev->min_mtu = ETH_ZLEN;
|
|
- net_dev->max_mtu = XRX200_DMA_DATA_LEN - VLAN_ETH_HLEN - ETH_FCS_LEN;
|
|
+ net_dev->max_mtu = XRX200_DMA_DATA_LEN - xrx200_max_frame_len(0);
|
|
+ priv->rx_buf_size = xrx200_buffer_size(ETH_DATA_LEN);
|
|
|
|
/* load the memory ranges */
|
|
priv->pmac_reg = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
|