diff options
Diffstat (limited to 'drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c')
| -rw-r--r-- | drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c new file mode 100644 index 000000000000..899c30fb5188 --- /dev/null +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c @@ -0,0 +1,240 @@ +/* Broadcom NetXtreme-C/E network driver. + * + * Copyright (c) 2016-2017 Broadcom Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/pci.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/if_vlan.h> +#include <linux/bpf.h> +#include <linux/bpf_trace.h> +#include <linux/filter.h> +#include "bnxt_hsi.h" +#include "bnxt.h" +#include "bnxt_xdp.h" + +static void bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_tx_ring_info *txr, + dma_addr_t mapping, u32 len, u16 rx_prod) +{ + struct bnxt_sw_tx_bd *tx_buf; + struct tx_bd_ext *txbd1; + struct tx_bd *txbd; + u32 flags; + u16 prod; + + prod = txr->tx_prod; + tx_buf = &txr->tx_buf_ring[prod]; + tx_buf->rx_prod = rx_prod; + + txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)]; + flags = (len << TX_BD_LEN_SHIFT) | TX_BD_TYPE_LONG_TX_BD | + (2 << TX_BD_FLAGS_BD_CNT_SHIFT) | TX_BD_FLAGS_COAL_NOW | + TX_BD_FLAGS_PACKET_END | bnxt_lhint_arr[len >> 9]; + txbd->tx_bd_len_flags_type = cpu_to_le32(flags); + txbd->tx_bd_opaque = prod; + txbd->tx_bd_haddr = cpu_to_le64(mapping); + + prod = NEXT_TX(prod); + txbd1 = (struct tx_bd_ext *) + &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)]; + + txbd1->tx_bd_hsize_lflags = cpu_to_le32(0); + txbd1->tx_bd_mss = cpu_to_le32(0); + txbd1->tx_bd_cfa_action = cpu_to_le32(0); + txbd1->tx_bd_cfa_meta = cpu_to_le32(0); + + prod = NEXT_TX(prod); + txr->tx_prod = prod; +} + +void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) +{ + struct bnxt_tx_ring_info *txr = bnapi->tx_ring; + struct bnxt_rx_ring_info *rxr = bnapi->rx_ring; + struct bnxt_sw_tx_bd *tx_buf; + u16 tx_cons = txr->tx_cons; + u16 last_tx_cons = tx_cons; + u16 rx_prod; + int i; + + for (i = 0; i < nr_pkts; i++) { + last_tx_cons = tx_cons; + tx_cons = NEXT_TX(tx_cons); + tx_cons = NEXT_TX(tx_cons); + } + txr->tx_cons = tx_cons; + if (bnxt_tx_avail(bp, txr) == bp->tx_ring_size) { + rx_prod = rxr->rx_prod; + } else { + tx_buf = &txr->tx_buf_ring[last_tx_cons]; + rx_prod = tx_buf->rx_prod; + } + writel(DB_KEY_RX | rx_prod, rxr->rx_doorbell); +} + +/* returns the following: + * true - packet consumed by XDP and new buffer is allocated. + * false - packet should be passed to the stack. + */ +bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, + struct page *page, u8 **data_ptr, unsigned int *len, u8 *event) +{ + struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog); + struct bnxt_tx_ring_info *txr; + struct bnxt_sw_rx_bd *rx_buf; + struct pci_dev *pdev; + struct xdp_buff xdp; + dma_addr_t mapping; + void *orig_data; + u32 tx_avail; + u32 offset; + u32 act; + + if (!xdp_prog) + return false; + + pdev = bp->pdev; + txr = rxr->bnapi->tx_ring; + rx_buf = &rxr->rx_buf_ring[cons]; + offset = bp->rx_offset; + + xdp.data_hard_start = *data_ptr - offset; + xdp.data = *data_ptr; + xdp.data_end = *data_ptr + *len; + orig_data = xdp.data; + mapping = rx_buf->mapping - bp->rx_dma_offset; + + dma_sync_single_for_cpu(&pdev->dev, mapping + offset, *len, bp->rx_dir); + + rcu_read_lock(); + act = bpf_prog_run_xdp(xdp_prog, &xdp); + rcu_read_unlock(); + + tx_avail = bnxt_tx_avail(bp, txr); + /* If the tx ring is not full, we must not update the rx producer yet + * because we may still be transmitting on some BDs. + */ + if (tx_avail != bp->tx_ring_size) + *event &= ~BNXT_RX_EVENT; + + if (orig_data != xdp.data) { + offset = xdp.data - xdp.data_hard_start; + *data_ptr = xdp.data_hard_start + offset; + *len = xdp.data_end - xdp.data; + } + switch (act) { + case XDP_PASS: + return false; + + case XDP_TX: + if (tx_avail < 2) { + trace_xdp_exception(bp->dev, xdp_prog, act); + 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); + bnxt_xmit_xdp(bp, txr, mapping + offset, *len, + NEXT_RX(rxr->rx_prod)); + bnxt_reuse_rx_data(rxr, cons, page); + return true; + default: + bpf_warn_invalid_xdp_action(act); + /* Fall thru */ + case XDP_ABORTED: + trace_xdp_exception(bp->dev, xdp_prog, act); + /* Fall thru */ + case XDP_DROP: + bnxt_reuse_rx_data(rxr, cons, page); + break; + } + return true; +} + +/* Under rtnl_lock */ +static int bnxt_xdp_set(struct bnxt *bp, struct bpf_prog *prog) +{ + struct net_device *dev = bp->dev; + int tx_xdp = 0, rc, tc; + struct bpf_prog *old; + + if (prog && bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU) { + netdev_warn(dev, "MTU %d larger than largest XDP supported MTU %d.\n", + bp->dev->mtu, BNXT_MAX_PAGE_MODE_MTU); + return -EOPNOTSUPP; + } + if (!(bp->flags & BNXT_FLAG_SHARED_RINGS)) { + netdev_warn(dev, "ethtool rx/tx channels must be combined to support XDP.\n"); + return -EOPNOTSUPP; + } + if (prog) + tx_xdp = bp->rx_nr_rings; + + tc = netdev_get_num_tc(dev); + if (!tc) + tc = 1; + rc = bnxt_reserve_rings(bp, bp->tx_nr_rings_per_tc, bp->rx_nr_rings, + tc, tx_xdp); + if (rc) { + netdev_warn(dev, "Unable to reserve enough TX rings to support XDP.\n"); + return rc; + } + if (netif_running(dev)) + bnxt_close_nic(bp, true, false); + + old = xchg(&bp->xdp_prog, prog); + if (old) + bpf_prog_put(old); + + if (prog) { + bnxt_set_rx_skb_mode(bp, true); + } else { + int rx, tx; + + bnxt_set_rx_skb_mode(bp, false); + bnxt_get_max_rings(bp, &rx, &tx, true); + if (rx > 1) { + bp->flags &= ~BNXT_FLAG_NO_AGG_RINGS; + bp->dev->hw_features |= NETIF_F_LRO; + } + } + bp->tx_nr_rings_xdp = tx_xdp; + bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tc + tx_xdp; + bp->cp_nr_rings = max_t(int, bp->tx_nr_rings, bp->rx_nr_rings); + bp->num_stat_ctxs = bp->cp_nr_rings; + bnxt_set_tpa_flags(bp); + bnxt_set_ring_params(bp); + + if (netif_running(dev)) + return bnxt_open_nic(bp, true, false); + + return 0; +} + +int bnxt_xdp(struct net_device *dev, struct netdev_xdp *xdp) +{ + struct bnxt *bp = netdev_priv(dev); + int rc; + + switch (xdp->command) { + case XDP_SETUP_PROG: + rc = bnxt_xdp_set(bp, xdp->prog); + break; + case XDP_QUERY_PROG: + xdp->prog_attached = !!bp->xdp_prog; + rc = 0; + break; + default: + rc = -EINVAL; + break; + } + return rc; +} |