/* 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;
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);
/* 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;
}
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;
case XDP_QUERY_PROG:
xdp->prog_id = bp->xdp_prog ? bp->xdp_prog->aux->id : 0;
rc = 0;
break;
default:
rc = -EINVAL;
break;
}
return rc;
}
