diff options
Diffstat (limited to 'drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c')
-rw-r--r-- | drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 484 |
1 files changed, 484 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 000000000..aa56db138 --- /dev/null +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c @@ -0,0 +1,484 @@ +/* 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" + +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, + struct xdp_buff *xdp) +{ + struct skb_shared_info *sinfo; + struct bnxt_sw_tx_bd *tx_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]; + 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) | + ((num_frags + 1) << TX_BD_FLAGS_BD_CNT_SHIFT) | + 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); + + /* 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_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; +} + +static void __bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_tx_ring_info *txr, + 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, xdp); + 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, NULL); + 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, j, frags; + + 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), + DMA_TO_DEVICE); + 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; + + 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); + } + 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); + + } +} + +bool bnxt_xdp_attached(struct bnxt *bp, struct bnxt_rx_ring_info *rxr) +{ + struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog); + + return !!xdp_prog; +} + +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) +{ + u32 buflen = BNXT_RX_PAGE_SIZE; + struct bnxt_sw_rx_bd *rx_buf; + struct pci_dev *pdev; + dma_addr_t mapping; + u32 offset; + + 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); + + xdp_init_buff(xdp, buflen, &rxr->xdp_rxq); + 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. + */ +bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, + struct xdp_buff xdp, 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; + dma_addr_t mapping; + u32 tx_needed = 1; + void *orig_data; + u32 tx_avail; + u32 offset; + u32 act; + + if (!xdp_prog) + return false; + + pdev = bp->pdev; + offset = bp->rx_offset; + + txr = rxr->bnapi->tx_ring; + /* BNXT_RX_PAGE_MODE(bp) when XDP enabled */ + orig_data = xdp.data; + + act = bpf_prog_run_xdp(xdp_prog, &xdp); + + 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: + 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); + + 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; + } + + 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), &xdp); + 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. + */ + rx_buf = &rxr->rx_buf_ring[cons]; + mapping = rx_buf->mapping - bp->rx_dma_offset; + dma_unmap_page_attrs(&pdev->dev, mapping, + BNXT_RX_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_xdp_buff_frags_free(rxr, &xdp); + 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(bp->dev, xdp_prog, act); + fallthrough; + case XDP_ABORTED: + 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; + } + 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 nxmit = 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]; + + if (READ_ONCE(txr->dev_state) == BNXT_DEV_STATE_CLOSING) + return -EINVAL; + + if (static_branch_unlikely(&bnxt_xdp_locking_key)) + spin_lock(&txr->xdp_tx_lock); + + for (i = 0; i < num_frames; i++) { + struct xdp_frame *xdp = frames[i]; + + if (!bnxt_tx_avail(bp, txr)) + break; + + mapping = dma_map_single(&pdev->dev, xdp->data, xdp->len, + DMA_TO_DEVICE); + + if (dma_mapping_error(&pdev->dev, mapping)) + break; + + __bnxt_xmit_xdp_redirect(bp, txr, mapping, xdp->len, xdp); + nxmit++; + } + + if (flags & XDP_XMIT_FLUSH) { + /* Sync BD data before updating doorbell */ + wmb(); + bnxt_db_write(bp, &txr->tx_db, txr->tx_prod); + } + + if (static_branch_unlikely(&bnxt_xdp_locking_key)) + spin_unlock(&txr->xdp_tx_lock); + + return nxmit; +} + +/* 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 && !prog->aux->xdp_has_frags && + bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU) { + netdev_warn(dev, "MTU %d larger than %d without XDP frag support.\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; +} + +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, + struct rx_cmp_ext *rxcmp1) +{ + struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); + + if (!skb) + return NULL; + skb_checksum_none_assert(skb); + if (RX_CMP_L4_CS_OK(rxcmp1)) { + if (bp->dev->features & NETIF_F_RXCSUM) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->csum_level = RX_CMP_ENCAP(rxcmp1); + } + } + xdp_update_skb_shared_info(skb, num_frags, + sinfo->xdp_frags_size, + BNXT_RX_PAGE_SIZE * sinfo->nr_frags, + xdp_buff_is_frag_pfmemalloc(xdp)); + return skb; +} |