/* 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/helpers.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[RING_TX(bp, 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(bp, 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 = SET_TX_OPAQUE(bp, txr, prod, 1 + num_frags);
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;
dma_addr_t frag_mapping;
int frag_len;
prod = NEXT_TX(prod);
WRITE_ONCE(txr->tx_prod, prod);
/* first fill up the first buffer */
frag_tx_buf = &txr->tx_buf_ring[RING_TX(bp, prod)];
frag_tx_buf->page = skb_frag_page(frag);
txbd = &txr->tx_desc_ring[TX_RING(bp, prod)][TX_IDX(prod)];
frag_len = skb_frag_size(frag);
flags = frag_len << TX_BD_LEN_SHIFT;
txbd->tx_bd_len_flags_type = cpu_to_le32(flags);
frag_mapping = page_pool_get_dma_addr(skb_frag_page(frag)) +
skb_frag_off(frag);
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);
WRITE_ONCE(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 budget)
{
struct bnxt_tx_ring_info *txr = bnapi->tx_ring[0];
struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;
u16 tx_hw_cons = txr->tx_hw_cons;
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 j, frags;
if (!budget)
return;
while (RING_TX(bp, tx_cons) != tx_hw_cons) {
tx_buf = &txr->tx_buf_ring[RING_TX(bp, 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) {
tx_buf->action = 0;
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[RING_TX(bp, tx_cons)];
page_pool_recycle_direct(rxr->page_pool, tx_buf->page);
}
} else {
bnxt_sched_reset_txr(bp, txr, tx_cons);
return;
}
tx_cons = NEXT_TX(tx_cons);
}
bnapi->events &= ~BNXT_TX_CMP_EVENT;
WRITE_ONCE(txr->tx_cons, tx_cons);
if (rx_doorbell_needed) {
tx_buf = &txr->tx_buf_ring[RING_TX(bp, 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, true);
}
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[0];
/* 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 &= BNXT_TX_CMP_EVENT;
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.
*/
/* 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, tx_cp, 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 = bp->num_tc;
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);
xdp_features_set_redirect_target(dev, true);
} else {
int rx, tx;
xdp_features_clear_redirect_target(dev);
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;
tx_cp = bnxt_num_tx_to_cp(bp, bp->tx_nr_rings);
bp->cp_nr_rings = max_t(int, tx_cp, 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;
}
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