From: Ulrich Hecht uli+renesas@fpond.eu
[ Upstream commit 15fb35fa9ff456b81159033eba6397fcee85e671 ]
Pre-allocates buffers sufficient for the maximum supported MTU (2026) in order to eliminate the possibility of resource exhaustion when changing the MTU while the device is up.
Signed-off-by: Ulrich Hecht uli+renesas@fpond.eu Reviewed-by: Sergei Shtylyov sergei.shtylyov@cogentembedded.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/renesas/ravb.h | 3 ++- drivers/net/ethernet/renesas/ravb_main.c | 26 +++++++++++++----------- 2 files changed, 16 insertions(+), 13 deletions(-)
diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h index ac9195add8116..7090229398227 100644 --- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h @@ -960,6 +960,8 @@ enum RAVB_QUEUE { #define NUM_RX_QUEUE 2 #define NUM_TX_QUEUE 2
+#define RX_BUF_SZ (2048 - ETH_FCS_LEN + sizeof(__sum16)) + /* TX descriptors per packet */ #define NUM_TX_DESC_GEN2 2 #define NUM_TX_DESC_GEN3 1 @@ -1023,7 +1025,6 @@ struct ravb_private { u32 dirty_rx[NUM_RX_QUEUE]; /* Producer ring indices */ u32 cur_tx[NUM_TX_QUEUE]; u32 dirty_tx[NUM_TX_QUEUE]; - u32 rx_buf_sz; /* Based on MTU+slack. */ struct napi_struct napi[NUM_RX_QUEUE]; struct work_struct work; /* MII transceiver section. */ diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 6cacd5e893aca..393644833cd57 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -230,7 +230,7 @@ static void ravb_ring_free(struct net_device *ndev, int q) le32_to_cpu(desc->dptr))) dma_unmap_single(ndev->dev.parent, le32_to_cpu(desc->dptr), - priv->rx_buf_sz, + RX_BUF_SZ, DMA_FROM_DEVICE); } ring_size = sizeof(struct ravb_ex_rx_desc) * @@ -293,9 +293,9 @@ static void ravb_ring_format(struct net_device *ndev, int q) for (i = 0; i < priv->num_rx_ring[q]; i++) { /* RX descriptor */ rx_desc = &priv->rx_ring[q][i]; - rx_desc->ds_cc = cpu_to_le16(priv->rx_buf_sz); + rx_desc->ds_cc = cpu_to_le16(RX_BUF_SZ); dma_addr = dma_map_single(ndev->dev.parent, priv->rx_skb[q][i]->data, - priv->rx_buf_sz, + RX_BUF_SZ, DMA_FROM_DEVICE); /* We just set the data size to 0 for a failed mapping which * should prevent DMA from happening... @@ -342,9 +342,6 @@ static int ravb_ring_init(struct net_device *ndev, int q) int ring_size; int i;
- priv->rx_buf_sz = (ndev->mtu <= 1492 ? PKT_BUF_SZ : ndev->mtu) + - ETH_HLEN + VLAN_HLEN + sizeof(__sum16); - /* Allocate RX and TX skb rings */ priv->rx_skb[q] = kcalloc(priv->num_rx_ring[q], sizeof(*priv->rx_skb[q]), GFP_KERNEL); @@ -354,7 +351,7 @@ static int ravb_ring_init(struct net_device *ndev, int q) goto error;
for (i = 0; i < priv->num_rx_ring[q]; i++) { - skb = netdev_alloc_skb(ndev, priv->rx_buf_sz + RAVB_ALIGN - 1); + skb = netdev_alloc_skb(ndev, RX_BUF_SZ + RAVB_ALIGN - 1); if (!skb) goto error; ravb_set_buffer_align(skb); @@ -590,7 +587,7 @@ static bool ravb_rx(struct net_device *ndev, int *quota, int q) skb = priv->rx_skb[q][entry]; priv->rx_skb[q][entry] = NULL; dma_unmap_single(ndev->dev.parent, le32_to_cpu(desc->dptr), - priv->rx_buf_sz, + RX_BUF_SZ, DMA_FROM_DEVICE); get_ts &= (q == RAVB_NC) ? RAVB_RXTSTAMP_TYPE_V2_L2_EVENT : @@ -623,11 +620,11 @@ static bool ravb_rx(struct net_device *ndev, int *quota, int q) for (; priv->cur_rx[q] - priv->dirty_rx[q] > 0; priv->dirty_rx[q]++) { entry = priv->dirty_rx[q] % priv->num_rx_ring[q]; desc = &priv->rx_ring[q][entry]; - desc->ds_cc = cpu_to_le16(priv->rx_buf_sz); + desc->ds_cc = cpu_to_le16(RX_BUF_SZ);
if (!priv->rx_skb[q][entry]) { skb = netdev_alloc_skb(ndev, - priv->rx_buf_sz + + RX_BUF_SZ + RAVB_ALIGN - 1); if (!skb) break; /* Better luck next round. */ @@ -1814,10 +1811,15 @@ static int ravb_do_ioctl(struct net_device *ndev, struct ifreq *req, int cmd)
static int ravb_change_mtu(struct net_device *ndev, int new_mtu) { - if (netif_running(ndev)) - return -EBUSY; + struct ravb_private *priv = netdev_priv(ndev);
ndev->mtu = new_mtu; + + if (netif_running(ndev)) { + synchronize_irq(priv->emac_irq); + ravb_emac_init(ndev); + } + netdev_update_features(ndev);
return 0;