[PATCH net-next 06/10] bnxt_en: Add tx ring mapping logic.

[Michael Chan]

To support XDP_TX, we need to add a set of dedicated TX rings, each
associated with the NAPI of an RX ring.  To assign XDP rings and regular
rings in a flexible way, we add a bp->tx_ring_map[] array to do the
remapping.  In this patch, before we introduce XDP_TX, the mapping is 1:1.

Signed-off-by: Michael Chan <michael.c...@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 11 ++++++++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |  1 +
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c 
b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index cb30ba4..db78103 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -262,8 +262,8 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, 
struct net_device *dev)
                return NETDEV_TX_OK;
        }
 
-       txr = &bp->tx_ring[i];
        txq = netdev_get_tx_queue(dev, i);
+       txr = &bp->tx_ring[bp->tx_ring_map[i]];
        prod = txr->tx_prod;
 
        free_size = bnxt_tx_avail(bp, txr);
@@ -2967,6 +2967,8 @@ static void bnxt_free_mem(struct bnxt *bp, bool 
irq_re_init)
                bnxt_free_stats(bp);
                bnxt_free_ring_grps(bp);
                bnxt_free_vnics(bp);
+               kfree(bp->tx_ring_map);
+               bp->tx_ring_map = NULL;
                kfree(bp->tx_ring);
                bp->tx_ring = NULL;
                kfree(bp->rx_ring);
@@ -3019,6 +3021,12 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool 
irq_re_init)
                if (!bp->tx_ring)
                        return -ENOMEM;
 
+               bp->tx_ring_map = kcalloc(bp->tx_nr_rings, sizeof(u16),
+                                         GFP_KERNEL);
+
+               if (!bp->tx_ring_map)
+                       return -ENOMEM;
+
                if (bp->flags & BNXT_FLAG_SHARED_RINGS)
                        j = 0;
                else
@@ -3027,6 +3035,7 @@ static int bnxt_alloc_mem(struct bnxt *bp, bool 
irq_re_init)
                for (i = 0; i < bp->tx_nr_rings; i++, j++) {
                        bp->tx_ring[i].bnapi = bp->bnapi[j];
                        bp->bnapi[j]->tx_ring = &bp->tx_ring[i];
+                       bp->tx_ring_map[i] = i;
                }
 
                rc = bnxt_alloc_stats(bp);
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h 
b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 44dcc26..924c1fa 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -995,6 +995,7 @@ struct bnxt {
 
        struct bnxt_rx_ring_info        *rx_ring;
        struct bnxt_tx_ring_info        *tx_ring;
+       u16                     *tx_ring_map;
 
        struct sk_buff *        (*gro_func)(struct bnxt_tpa_info *, int, int,
                                            struct sk_buff *);
-- 
1.8.3.1