From 9cfeeb576d49a7b5e643b8066ba64a55e8417c5d Mon Sep 17 00:00:00 2001 From: Yangchun Fu Date: Fri, 1 Nov 2019 10:09:56 -0700 Subject: gve: Fixes DMA synchronization. Synces the DMA buffer properly in order for CPU and device to see the most up-to-data data. Signed-off-by: Yangchun Fu Reviewed-by: Catherine Sullivan Signed-off-by: David S. Miller --- drivers/net/ethernet/google/gve/gve_tx.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) (limited to 'drivers/net/ethernet/google/gve/gve_tx.c') diff --git a/drivers/net/ethernet/google/gve/gve_tx.c b/drivers/net/ethernet/google/gve/gve_tx.c index 778b87b5a06c..0a9a7ee2a866 100644 --- a/drivers/net/ethernet/google/gve/gve_tx.c +++ b/drivers/net/ethernet/google/gve/gve_tx.c @@ -390,7 +390,21 @@ static void gve_tx_fill_seg_desc(union gve_tx_desc *seg_desc, seg_desc->seg.seg_addr = cpu_to_be64(addr); } -static int gve_tx_add_skb(struct gve_tx_ring *tx, struct sk_buff *skb) +static void gve_dma_sync_for_device(struct device *dev, dma_addr_t *page_buses, + u64 iov_offset, u64 iov_len) +{ + dma_addr_t dma; + u64 addr; + + for (addr = iov_offset; addr < iov_offset + iov_len; + addr += PAGE_SIZE) { + dma = page_buses[addr / PAGE_SIZE]; + dma_sync_single_for_device(dev, dma, PAGE_SIZE, DMA_TO_DEVICE); + } +} + +static int gve_tx_add_skb(struct gve_tx_ring *tx, struct sk_buff *skb, + struct device *dev) { int pad_bytes, hlen, hdr_nfrags, payload_nfrags, l4_hdr_offset; union gve_tx_desc *pkt_desc, *seg_desc; @@ -432,6 +446,9 @@ static int gve_tx_add_skb(struct gve_tx_ring *tx, struct sk_buff *skb) skb_copy_bits(skb, 0, tx->tx_fifo.base + info->iov[hdr_nfrags - 1].iov_offset, hlen); + gve_dma_sync_for_device(dev, tx->tx_fifo.qpl->page_buses, + info->iov[hdr_nfrags - 1].iov_offset, + info->iov[hdr_nfrags - 1].iov_len); copy_offset = hlen; for (i = payload_iov; i < payload_nfrags + payload_iov; i++) { @@ -445,6 +462,9 @@ static int gve_tx_add_skb(struct gve_tx_ring *tx, struct sk_buff *skb) skb_copy_bits(skb, copy_offset, tx->tx_fifo.base + info->iov[i].iov_offset, info->iov[i].iov_len); + gve_dma_sync_for_device(dev, tx->tx_fifo.qpl->page_buses, + info->iov[i].iov_offset, + info->iov[i].iov_len); copy_offset += info->iov[i].iov_len; } @@ -473,7 +493,7 @@ netdev_tx_t gve_tx(struct sk_buff *skb, struct net_device *dev) gve_tx_put_doorbell(priv, tx->q_resources, tx->req); return NETDEV_TX_BUSY; } - nsegs = gve_tx_add_skb(tx, skb); + nsegs = gve_tx_add_skb(tx, skb, &priv->pdev->dev); netdev_tx_sent_queue(tx->netdev_txq, skb->len); skb_tx_timestamp(skb); -- cgit v1.2.3-59-g8ed1b