bnxt: support transmit and free of aggregation buffers

This patch adds the following features:
- Support for XDP_TX and XDP_DROP action when using xdp_buff
  with frags
- Support for freeing all frags attached to an xdp_buff
- Cleanup of TX ring buffers after transmits complete
- Slight change in definition of bnxt_sw_tx_bd since nr_frags
  and RX producer may both need to be used
- Clear out skb_shared_info at the end of the buffer

v2: Fix uninitialized variable warning in bnxt_xdp_buff_frags_free().

Signed-off-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index f96f41c..25d74c9 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -1951,9 +1951,13 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr,
                skb = bnxt_copy_skb(bnapi, data_ptr, len, dma_addr);
                bnxt_reuse_rx_data(rxr, cons, data);
                if (!skb) {
-                       if (agg_bufs)
-                               bnxt_reuse_rx_agg_bufs(cpr, cp_cons, 0,
-                                                      agg_bufs, false);
+                       if (agg_bufs) {
+                               if (!xdp_active)
+                                       bnxt_reuse_rx_agg_bufs(cpr, cp_cons, 0,
+                                                              agg_bufs, false);
+                               else
+                                       bnxt_xdp_buff_frags_free(rxr, &xdp);
+                       }
                        cpr->sw_stats.rx.rx_oom_discards += 1;
                        rc = -ENOMEM;
                        goto next_rx;
@@ -1986,6 +1990,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr,
                        skb = bnxt_xdp_build_skb(bp, skb, agg_bufs, rxr->page_pool, &xdp, rxcmp1);
                        if (!skb) {
                                /* we should be able to free the old skb here */
+                               bnxt_xdp_buff_frags_free(rxr, &xdp);
                                cpr->sw_stats.rx.rx_oom_discards += 1;
                                rc = -ENOMEM;
                                goto next_rx;
@@ -2605,10 +2610,13 @@ static void __bnxt_poll_work_done(struct bnxt *bp, struct bnxt_napi *bnapi)
        if ((bnapi->events & BNXT_RX_EVENT) && !(bnapi->in_reset)) {
                struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
 
-               if (bnapi->events & BNXT_AGG_EVENT)
-                       bnxt_db_write(bp, &rxr->rx_agg_db, rxr->rx_agg_prod);
                bnxt_db_write(bp, &rxr->rx_db, rxr->rx_prod);
        }
+       if (bnapi->events & BNXT_AGG_EVENT) {
+               struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
+
+               bnxt_db_write(bp, &rxr->rx_agg_db, rxr->rx_agg_prod);
+       }
        bnapi->events = 0;
 }
 

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 319d685..a498ee2 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -701,13 +701,12 @@ struct bnxt_sw_tx_bd {
        };
        DEFINE_DMA_UNMAP_ADDR(mapping);
        DEFINE_DMA_UNMAP_LEN(len);
+       struct page             *page;
        u8                      is_gso;
        u8                      is_push;
        u8                      action;
-       union {
-               unsigned short          nr_frags;
-               u16                     rx_prod;
-       };
+       unsigned short          nr_frags;
+       u16                     rx_prod;
 };
 
 struct bnxt_sw_rx_bd {

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 22e965e..b3a48d6 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -3491,7 +3491,7 @@ static int bnxt_run_loopback(struct bnxt *bp)
                dev_kfree_skb(skb);
                return -EIO;
        }
-       bnxt_xmit_bd(bp, txr, map, pkt_size);
+       bnxt_xmit_bd(bp, txr, map, pkt_size, NULL);
 
        /* Sync BD data before updating doorbell */
        wmb();

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
index 5183357..c2905f0 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -24,36 +24,91 @@ DEFINE_STATIC_KEY_FALSE(bnxt_xdp_locking_key);
 
 struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp,
                                   struct bnxt_tx_ring_info *txr,
-                                  dma_addr_t mapping, u32 len)
+                                  dma_addr_t mapping, u32 len,
+                                  struct xdp_buff *xdp)
 {
-       struct bnxt_sw_tx_bd *tx_buf;
+       struct skb_shared_info *sinfo;
+       struct bnxt_sw_tx_bd *tx_buf, *first_buf;
        struct tx_bd *txbd;
+       int num_frags = 0;
        u32 flags;
        u16 prod;
+       int i;
+
+       if (xdp && xdp_buff_has_frags(xdp)) {
+               sinfo = xdp_get_shared_info_from_buff(xdp);
+               num_frags = sinfo->nr_frags;
+       }
 
+       /* fill up the first buffer */
        prod = txr->tx_prod;
        tx_buf = &txr->tx_buf_ring[prod];
+       first_buf = tx_buf;
+       tx_buf->nr_frags = num_frags;
+       if (xdp)
+               tx_buf->page = virt_to_head_page(xdp->data);
 
        txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
-       flags = (len << TX_BD_LEN_SHIFT) | (1 << TX_BD_FLAGS_BD_CNT_SHIFT) |
-               TX_BD_FLAGS_PACKET_END | bnxt_lhint_arr[len >> 9];
+       flags = ((len) << TX_BD_LEN_SHIFT) | ((num_frags + 1) << TX_BD_FLAGS_BD_CNT_SHIFT);
        txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
        txbd->tx_bd_opaque = prod;
        txbd->tx_bd_haddr = cpu_to_le64(mapping);
 
+       /* now let us fill up the frags into the next buffers */
+       for (i = 0; i < num_frags ; i++) {
+               skb_frag_t *frag = &sinfo->frags[i];
+               struct bnxt_sw_tx_bd *frag_tx_buf;
+               struct pci_dev *pdev = bp->pdev;
+               dma_addr_t frag_mapping;
+               int frag_len;
+
+               prod = NEXT_TX(prod);
+               txr->tx_prod = prod;
+
+               /* first fill up the first buffer */
+               frag_tx_buf = &txr->tx_buf_ring[prod];
+               frag_tx_buf->page = skb_frag_page(frag);
+
+               txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];
+
+               frag_len = skb_frag_size(frag);
+               frag_mapping = skb_frag_dma_map(&pdev->dev, frag, 0,
+                                               frag_len, DMA_TO_DEVICE);
+
+               if (unlikely(dma_mapping_error(&pdev->dev, frag_mapping)))
+                       return NULL;
+
+               dma_unmap_addr_set(frag_tx_buf, mapping, frag_mapping);
+
+               flags = frag_len << TX_BD_LEN_SHIFT;
+               txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
+               txbd->tx_bd_opaque = prod;
+               txbd->tx_bd_haddr = cpu_to_le64(frag_mapping);
+
+               len = frag_len;
+       }
+
+       flags &= ~TX_BD_LEN;
+       txbd->tx_bd_len_flags_type = cpu_to_le32(((len) << TX_BD_LEN_SHIFT) | flags |
+                       TX_BD_FLAGS_PACKET_END);
+       /* Sync TX BD */
+       wmb();
        prod = NEXT_TX(prod);
        txr->tx_prod = prod;
-       return tx_buf;
+
+       return first_buf;
 }
 
 static void __bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_tx_ring_info *txr,
-                           dma_addr_t mapping, u32 len, u16 rx_prod)
+                           dma_addr_t mapping, u32 len, u16 rx_prod,
+                           struct xdp_buff *xdp)
 {
        struct bnxt_sw_tx_bd *tx_buf;
 
-       tx_buf = bnxt_xmit_bd(bp, txr, mapping, len);
+       tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, xdp);
        tx_buf->rx_prod = rx_prod;
        tx_buf->action = XDP_TX;
+
 }
 
 static void __bnxt_xmit_xdp_redirect(struct bnxt *bp,
@@ -63,7 +118,7 @@ static void __bnxt_xmit_xdp_redirect(struct bnxt *bp,
 {
        struct bnxt_sw_tx_bd *tx_buf;
 
-       tx_buf = bnxt_xmit_bd(bp, txr, mapping, len);
+       tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, NULL);
        tx_buf->action = XDP_REDIRECT;
        tx_buf->xdpf = xdpf;
        dma_unmap_addr_set(tx_buf, mapping, mapping);
@@ -78,7 +133,7 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts)
        struct bnxt_sw_tx_bd *tx_buf;
        u16 tx_cons = txr->tx_cons;
        u16 last_tx_cons = tx_cons;
-       int i;
+       int i, j, frags;
 
        for (i = 0; i < nr_pkts; i++) {
                tx_buf = &txr->tx_buf_ring[tx_cons];
@@ -96,6 +151,13 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts)
                } else if (tx_buf->action == XDP_TX) {
                        rx_doorbell_needed = true;
                        last_tx_cons = tx_cons;
+
+                       frags = tx_buf->nr_frags;
+                       for (j = 0; j < frags; j++) {
+                               tx_cons = NEXT_TX(tx_cons);
+                               tx_buf = &txr->tx_buf_ring[tx_cons];
+                               page_pool_recycle_direct(rxr->page_pool, tx_buf->page);
+                       }
                }
                tx_cons = NEXT_TX(tx_cons);
        }
@@ -103,6 +165,7 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts)
        if (rx_doorbell_needed) {
                tx_buf = &txr->tx_buf_ring[last_tx_cons];
                bnxt_db_write(bp, &rxr->rx_db, tx_buf->rx_prod);
+
        }
 }
 
@@ -133,6 +196,23 @@ void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
        xdp_prepare_buff(xdp, *data_ptr - offset, offset, *len, false);
 }
 
+void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr,
+                             struct xdp_buff *xdp)
+{
+       struct skb_shared_info *shinfo;
+       int i;
+
+       if (!xdp || !xdp_buff_has_frags(xdp))
+               return;
+       shinfo = xdp_get_shared_info_from_buff(xdp);
+       for (i = 0; i < shinfo->nr_frags; i++) {
+               struct page *page = skb_frag_page(&shinfo->frags[i]);
+
+               page_pool_recycle_direct(rxr->page_pool, page);
+       }
+       shinfo->nr_frags = 0;
+}
+
 /* returns the following:
  * true    - packet consumed by XDP and new buffer is allocated.
  * false   - packet should be passed to the stack.
@@ -145,6 +225,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
        struct bnxt_sw_rx_bd *rx_buf;
        struct pci_dev *pdev;
        dma_addr_t mapping;
+       u32 tx_needed = 1;
        void *orig_data;
        u32 tx_avail;
        u32 offset;
@@ -180,18 +261,28 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
        case XDP_TX:
                rx_buf = &rxr->rx_buf_ring[cons];
                mapping = rx_buf->mapping - bp->rx_dma_offset;
+               *event = 0;
+
+               if (unlikely(xdp_buff_has_frags(&xdp))) {
+                       struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(&xdp);
 
-               if (tx_avail < 1) {
+                       tx_needed += sinfo->nr_frags;
+                       *event = BNXT_AGG_EVENT;
+               }
+
+               if (tx_avail < tx_needed) {
                        trace_xdp_exception(bp->dev, xdp_prog, act);
+                       bnxt_xdp_buff_frags_free(rxr, &xdp);
                        bnxt_reuse_rx_data(rxr, cons, page);
                        return true;
                }
 
-               *event = BNXT_TX_EVENT;
                dma_sync_single_for_device(&pdev->dev, mapping + offset, *len,
                                           bp->rx_dir);
+
+               *event |= BNXT_TX_EVENT;
                __bnxt_xmit_xdp(bp, txr, mapping + offset, *len,
-                               NEXT_RX(rxr->rx_prod));
+                               NEXT_RX(rxr->rx_prod), &xdp);
                bnxt_reuse_rx_data(rxr, cons, page);
                return true;
        case XDP_REDIRECT:
@@ -208,6 +299,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
                /* if we are unable to allocate a new buffer, abort and reuse */
                if (bnxt_alloc_rx_data(bp, rxr, rxr->rx_prod, GFP_ATOMIC)) {
                        trace_xdp_exception(bp->dev, xdp_prog, act);
+                       bnxt_xdp_buff_frags_free(rxr, &xdp);
                        bnxt_reuse_rx_data(rxr, cons, page);
                        return true;
                }
@@ -227,6 +319,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
                trace_xdp_exception(bp->dev, xdp_prog, act);
                fallthrough;
        case XDP_DROP:
+               bnxt_xdp_buff_frags_free(rxr, &xdp);
                bnxt_reuse_rx_data(rxr, cons, page);
                break;
        }

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
index 27290f6..505911a 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
@@ -14,7 +14,8 @@ DECLARE_STATIC_KEY_FALSE(bnxt_xdp_locking_key);
 
 struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp,
                                   struct bnxt_tx_ring_info *txr,
-                                  dma_addr_t mapping, u32 len);
+                                  dma_addr_t mapping, u32 len,
+                                  struct xdp_buff *xdp);
 void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts);
 bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
                 struct xdp_buff xdp, struct page *page, unsigned int *len,
@@ -28,6 +29,8 @@ bool bnxt_xdp_attached(struct bnxt *bp, struct bnxt_rx_ring_info *rxr);
 void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
                        u16 cons, u8 **data_ptr, unsigned int *len,
                        struct xdp_buff *xdp);
+void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr,
+                             struct xdp_buff *xdp);
 struct sk_buff *bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb,
                                   u8 num_frags, struct page_pool *pool,
                                   struct xdp_buff *xdp,