| /* 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 <net/page_pool.h> |
| #include "bnxt_hsi.h" |
| #include "bnxt.h" |
| #include "bnxt_xdp.h" |
| |
| struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp, |
| struct bnxt_tx_ring_info *txr, |
| dma_addr_t mapping, u32 len) |
| { |
| struct bnxt_sw_tx_bd *tx_buf; |
| struct tx_bd *txbd; |
| u32 flags; |
| u16 prod; |
| |
| prod = txr->tx_prod; |
| tx_buf = &txr->tx_buf_ring[prod]; |
| |
| 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]; |
| 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); |
| txr->tx_prod = prod; |
| return tx_buf; |
| } |
| |
| 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; |
| |
| tx_buf = bnxt_xmit_bd(bp, txr, mapping, len); |
| tx_buf->rx_prod = rx_prod; |
| tx_buf->action = XDP_TX; |
| } |
| |
| static void __bnxt_xmit_xdp_redirect(struct bnxt *bp, |
| struct bnxt_tx_ring_info *txr, |
| dma_addr_t mapping, u32 len, |
| struct xdp_frame *xdpf) |
| { |
| struct bnxt_sw_tx_bd *tx_buf; |
| |
| tx_buf = bnxt_xmit_bd(bp, txr, mapping, len); |
| tx_buf->action = XDP_REDIRECT; |
| tx_buf->xdpf = xdpf; |
| dma_unmap_addr_set(tx_buf, mapping, mapping); |
| dma_unmap_len_set(tx_buf, len, 0); |
| } |
| |
| 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; |
| bool rx_doorbell_needed = false; |
| struct bnxt_sw_tx_bd *tx_buf; |
| u16 tx_cons = txr->tx_cons; |
| u16 last_tx_cons = tx_cons; |
| int i; |
| |
| for (i = 0; i < nr_pkts; i++) { |
| tx_buf = &txr->tx_buf_ring[tx_cons]; |
| |
| if (tx_buf->action == XDP_REDIRECT) { |
| struct pci_dev *pdev = bp->pdev; |
| |
| dma_unmap_single(&pdev->dev, |
| dma_unmap_addr(tx_buf, mapping), |
| dma_unmap_len(tx_buf, len), |
| PCI_DMA_TODEVICE); |
| xdp_return_frame(tx_buf->xdpf); |
| tx_buf->action = 0; |
| tx_buf->xdpf = NULL; |
| } else if (tx_buf->action == XDP_TX) { |
| rx_doorbell_needed = true; |
| last_tx_cons = tx_cons; |
| } |
| tx_cons = NEXT_TX(tx_cons); |
| } |
| txr->tx_cons = tx_cons; |
| if (rx_doorbell_needed) { |
| tx_buf = &txr->tx_buf_ring[last_tx_cons]; |
| bnxt_db_write(bp, &rxr->rx_db, tx_buf->rx_prod); |
| } |
| } |
| |
| /* 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; |
| rx_buf = &rxr->rx_buf_ring[cons]; |
| offset = bp->rx_offset; |
| |
| mapping = rx_buf->mapping - bp->rx_dma_offset; |
| dma_sync_single_for_cpu(&pdev->dev, mapping + offset, *len, bp->rx_dir); |
| |
| txr = rxr->bnapi->tx_ring; |
| xdp.data_hard_start = *data_ptr - offset; |
| xdp.data = *data_ptr; |
| xdp_set_data_meta_invalid(&xdp); |
| xdp.data_end = *data_ptr + *len; |
| xdp.rxq = &rxr->xdp_rxq; |
| xdp.frame_sz = PAGE_SIZE; /* BNXT_RX_PAGE_MODE(bp) when XDP enabled */ |
| orig_data = xdp.data; |
| |
| 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; |
| |
| *len = xdp.data_end - xdp.data; |
| if (orig_data != xdp.data) { |
| offset = xdp.data - xdp.data_hard_start; |
| *data_ptr = xdp.data_hard_start + offset; |
| } |
| switch (act) { |
| case XDP_PASS: |
| return false; |
| |
| case XDP_TX: |
| if (tx_avail < 1) { |
| 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; |
| case XDP_REDIRECT: |
| /* if we are calling this here then we know that the |
| * redirect is coming from a frame received by the |
| * bnxt_en driver. |
| */ |
| dma_unmap_page_attrs(&pdev->dev, mapping, |
| PAGE_SIZE, bp->rx_dir, |
| DMA_ATTR_WEAK_ORDERING); |
| |
| /* 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_reuse_rx_data(rxr, cons, page); |
| return true; |
| } |
| |
| if (xdp_do_redirect(bp->dev, &xdp, xdp_prog)) { |
| trace_xdp_exception(bp->dev, xdp_prog, act); |
| page_pool_recycle_direct(rxr->page_pool, page); |
| return true; |
| } |
| |
| *event |= BNXT_REDIRECT_EVENT; |
| break; |
| default: |
| bpf_warn_invalid_xdp_action(act); |
| fallthrough; |
| case XDP_ABORTED: |
| trace_xdp_exception(bp->dev, xdp_prog, act); |
| fallthrough; |
| case XDP_DROP: |
| bnxt_reuse_rx_data(rxr, cons, page); |
| break; |
| } |
| return true; |
| } |
| |
| int bnxt_xdp_xmit(struct net_device *dev, int num_frames, |
| struct xdp_frame **frames, u32 flags) |
| { |
| struct bnxt *bp = netdev_priv(dev); |
| struct bpf_prog *xdp_prog = READ_ONCE(bp->xdp_prog); |
| struct pci_dev *pdev = bp->pdev; |
| struct bnxt_tx_ring_info *txr; |
| dma_addr_t mapping; |
| int drops = 0; |
| int ring; |
| int i; |
| |
| if (!test_bit(BNXT_STATE_OPEN, &bp->state) || |
| !bp->tx_nr_rings_xdp || |
| !xdp_prog) |
| return -EINVAL; |
| |
| ring = smp_processor_id() % bp->tx_nr_rings_xdp; |
| txr = &bp->tx_ring[ring]; |
| |
| for (i = 0; i < num_frames; i++) { |
| struct xdp_frame *xdp = frames[i]; |
| |
| if (!txr || !bnxt_tx_avail(bp, txr) || |
| !(bp->bnapi[ring]->flags & BNXT_NAPI_FLAG_XDP)) { |
| xdp_return_frame_rx_napi(xdp); |
| drops++; |
| continue; |
| } |
| |
| mapping = dma_map_single(&pdev->dev, xdp->data, xdp->len, |
| DMA_TO_DEVICE); |
| |
| if (dma_mapping_error(&pdev->dev, mapping)) { |
| xdp_return_frame_rx_napi(xdp); |
| drops++; |
| continue; |
| } |
| __bnxt_xmit_xdp_redirect(bp, txr, mapping, xdp->len, xdp); |
| } |
| |
| if (flags & XDP_XMIT_FLUSH) { |
| /* Sync BD data before updating doorbell */ |
| wmb(); |
| bnxt_db_write(bp, &txr->tx_db, txr->tx_prod); |
| } |
| |
| return num_frames - drops; |
| } |
| |
| /* 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_check_rings(bp, bp->tx_nr_rings_per_tc, bp->rx_nr_rings, |
| true, 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); |
| 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_bpf *xdp) |
| { |
| struct bnxt *bp = netdev_priv(dev); |
| int rc; |
| |
| switch (xdp->command) { |
| case XDP_SETUP_PROG: |
| rc = bnxt_xdp_set(bp, xdp->prog); |
| break; |
| default: |
| rc = -EINVAL; |
| break; |
| } |
| return rc; |
| } |