Support devmem Tx. We already use skb_frag_dma_map(), we just need to make sure we don't try to unmap the frags. Check if frag is unreadable and mark the ring entry. # ./tools/testing/selftests/drivers/net/hw/devmem.py TAP version 13 1..3 ok 1 devmem.check_rx ok 2 devmem.check_tx ok 3 devmem.check_tx_chunks # Totals: pass:3 fail:0 xfail:0 xpass:0 skip:0 error:0 Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/meta/fbnic/fbnic_netdev.c | 1 + drivers/net/ethernet/meta/fbnic/fbnic_txrx.c | 14 +++++++++++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c index dd35de301870..d12b4cad84a5 100644 --- a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c +++ b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c @@ -712,6 +712,7 @@ struct net_device *fbnic_netdev_alloc(struct fbnic_dev *fbd) netdev->netdev_ops = &fbnic_netdev_ops; netdev->stat_ops = &fbnic_stat_ops; netdev->queue_mgmt_ops = &fbnic_queue_mgmt_ops; + netdev->netmem_tx = true; fbnic_set_ethtool_ops(netdev); diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c index ac555e045e34..286ad628a557 100644 --- a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c +++ b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c @@ -37,6 +37,8 @@ struct fbnic_xmit_cb { #define FBNIC_XMIT_CB(__skb) ((struct fbnic_xmit_cb *)((__skb)->cb)) +#define FBNIC_XMIT_NOUNMAP (void *)1 + static u32 __iomem *fbnic_ring_csr_base(const struct fbnic_ring *ring) { unsigned long csr_base = (unsigned long)ring->doorbell; @@ -315,6 +317,7 @@ fbnic_tx_map(struct fbnic_ring *ring, struct sk_buff *skb, __le64 *meta) unsigned int tail = ring->tail, first; unsigned int size, data_len; skb_frag_t *frag; + bool is_net_iov; dma_addr_t dma; __le64 *twd; @@ -330,6 +333,7 @@ fbnic_tx_map(struct fbnic_ring *ring, struct sk_buff *skb, __le64 *meta) if (size > FIELD_MAX(FBNIC_TWD_LEN_MASK)) goto dma_error; + is_net_iov = false; dma = dma_map_single(dev, skb->data, size, DMA_TO_DEVICE); for (frag = &skb_shinfo(skb)->frags[0];; frag++) { @@ -342,6 +346,8 @@ fbnic_tx_map(struct fbnic_ring *ring, struct sk_buff *skb, __le64 *meta) FIELD_PREP(FBNIC_TWD_LEN_MASK, size) | FIELD_PREP(FBNIC_TWD_TYPE_MASK, FBNIC_TWD_TYPE_AL)); + if (is_net_iov) + ring->tx_buf[tail] = FBNIC_XMIT_NOUNMAP; tail++; tail &= ring->size_mask; @@ -355,6 +361,7 @@ fbnic_tx_map(struct fbnic_ring *ring, struct sk_buff *skb, __le64 *meta) if (size > FIELD_MAX(FBNIC_TWD_LEN_MASK)) goto dma_error; + is_net_iov = skb_frag_is_net_iov(frag); dma = skb_frag_dma_map(dev, frag, 0, size, DMA_TO_DEVICE); } @@ -387,6 +394,7 @@ fbnic_tx_map(struct fbnic_ring *ring, struct sk_buff *skb, __le64 *meta) while (tail != first) { tail--; tail &= ring->size_mask; + ring->tx_buf[tail] = NULL; twd = &ring->desc[tail]; if (tail == first) fbnic_unmap_single_twd(dev, twd); @@ -574,7 +582,11 @@ static void fbnic_clean_twq0(struct fbnic_napi_vector *nv, int napi_budget, desc_cnt--; while (desc_cnt--) { - fbnic_unmap_page_twd(nv->dev, &ring->desc[head]); + if (ring->tx_buf[head] != FBNIC_XMIT_NOUNMAP) + fbnic_unmap_page_twd(nv->dev, + &ring->desc[head]); + else + ring->tx_buf[head] = NULL; head++; head &= ring->size_mask; } -- 2.51.0