i40e: add xdp frags support to ndo_xdp_xmit

Add the capability to map non-linear xdp frames in XDP_TX and ndo_xdp_xmit
callback.

Tested-by: Sarkar Tirthendu <tirthendu.sarkar@intel.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Tested-by: George Kuruvinakunnel <george.kuruvinakunnel@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 7bc1174edf6b9c1803eabd05a5d2bf0c6bb65317..b7967105a5490f35df59df158efca2a391203f75 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2509,6 +2509,7 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
                        hard_start = page_address(rx_buffer->page) +
                                     rx_buffer->page_offset - offset;
                        xdp_prepare_buff(&xdp, hard_start, offset, size, true);
+                       xdp_buff_clear_frags_flag(&xdp);
 #if (PAGE_SIZE > 4096)
                        /* At larger PAGE_SIZE, frame_sz depend on len size */
                        xdp.frame_sz = i40e_rx_frame_truesize(rx_ring, size);
@@ -3713,35 +3714,55 @@ u16 i40e_lan_select_queue(struct net_device *netdev,
 static int i40e_xmit_xdp_ring(struct xdp_frame *xdpf,
                              struct i40e_ring *xdp_ring)
 {
-       u16 i = xdp_ring->next_to_use;
-       struct i40e_tx_buffer *tx_bi;
-       struct i40e_tx_desc *tx_desc;
+       struct skb_shared_info *sinfo = xdp_get_shared_info_from_frame(xdpf);
+       u8 nr_frags = unlikely(xdp_frame_has_frags(xdpf)) ? sinfo->nr_frags : 0;
+       u16 i = 0, index = xdp_ring->next_to_use;
+       struct i40e_tx_buffer *tx_head = &xdp_ring->tx_bi[index];
+       struct i40e_tx_buffer *tx_bi = tx_head;
+       struct i40e_tx_desc *tx_desc = I40E_TX_DESC(xdp_ring, index);
        void *data = xdpf->data;
        u32 size = xdpf->len;
-       dma_addr_t dma;
 
-       if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
+       if (unlikely(I40E_DESC_UNUSED(xdp_ring) < 1 + nr_frags)) {
                xdp_ring->tx_stats.tx_busy++;
                return I40E_XDP_CONSUMED;
        }
-       dma = dma_map_single(xdp_ring->dev, data, size, DMA_TO_DEVICE);
-       if (dma_mapping_error(xdp_ring->dev, dma))
-               return I40E_XDP_CONSUMED;
 
-       tx_bi = &xdp_ring->tx_bi[i];
-       tx_bi->bytecount = size;
-       tx_bi->gso_segs = 1;
-       tx_bi->xdpf = xdpf;
+       tx_head->bytecount = xdp_get_frame_len(xdpf);
+       tx_head->gso_segs = 1;
+       tx_head->xdpf = xdpf;
 
-       /* record length, and DMA address */
-       dma_unmap_len_set(tx_bi, len, size);
-       dma_unmap_addr_set(tx_bi, dma, dma);
+       for (;;) {
+               dma_addr_t dma;
 
-       tx_desc = I40E_TX_DESC(xdp_ring, i);
-       tx_desc->buffer_addr = cpu_to_le64(dma);
-       tx_desc->cmd_type_offset_bsz = build_ctob(I40E_TX_DESC_CMD_ICRC
-                                                 | I40E_TXD_CMD,
-                                                 0, size, 0);
+               dma = dma_map_single(xdp_ring->dev, data, size, DMA_TO_DEVICE);
+               if (dma_mapping_error(xdp_ring->dev, dma))
+                       goto unmap;
+
+               /* record length, and DMA address */
+               dma_unmap_len_set(tx_bi, len, size);
+               dma_unmap_addr_set(tx_bi, dma, dma);
+
+               tx_desc->buffer_addr = cpu_to_le64(dma);
+               tx_desc->cmd_type_offset_bsz =
+                       build_ctob(I40E_TX_DESC_CMD_ICRC, 0, size, 0);
+
+               if (++index == xdp_ring->count)
+                       index = 0;
+
+               if (i == nr_frags)
+                       break;
+
+               tx_bi = &xdp_ring->tx_bi[index];
+               tx_desc = I40E_TX_DESC(xdp_ring, index);
+
+               data = skb_frag_address(&sinfo->frags[i]);
+               size = skb_frag_size(&sinfo->frags[i]);
+               i++;
+       }
+
+       tx_desc->cmd_type_offset_bsz |=
+               cpu_to_le64(I40E_TXD_CMD << I40E_TXD_QW1_CMD_SHIFT);
 
        /* Make certain all of the status bits have been updated
         * before next_to_watch is written.
@@ -3749,14 +3770,30 @@ static int i40e_xmit_xdp_ring(struct xdp_frame *xdpf,
        smp_wmb();
 
        xdp_ring->xdp_tx_active++;
-       i++;
-       if (i == xdp_ring->count)
-               i = 0;
 
-       tx_bi->next_to_watch = tx_desc;
-       xdp_ring->next_to_use = i;
+       tx_head->next_to_watch = tx_desc;
+       xdp_ring->next_to_use = index;
 
        return I40E_XDP_TX;
+
+unmap:
+       for (;;) {
+               tx_bi = &xdp_ring->tx_bi[index];
+               if (dma_unmap_len(tx_bi, len))
+                       dma_unmap_page(xdp_ring->dev,
+                                      dma_unmap_addr(tx_bi, dma),
+                                      dma_unmap_len(tx_bi, len),
+                                      DMA_TO_DEVICE);
+               dma_unmap_len_set(tx_bi, len, 0);
+               if (tx_bi == tx_head)
+                       break;
+
+               if (!index)
+                       index += xdp_ring->count;
+               index--;
+       }
+
+       return I40E_XDP_CONSUMED;
 }
 
 /**