net/mlx5e: Support bpf_xdp_adjust_head()

This patch adds bpf_xdp_adjust_head() support to mlx5e.

1. rx_headroom is added to struct mlx5e_rq.  It uses
   an existing 4 byte hole in the struct.
2. The adjusted data length is checked against
   MLX5E_XDP_MIN_INLINE and MLX5E_SW2HW_MTU(rq->netdev->mtu).
3. The macro MLX5E_SW2HW_MTU is moved from en_main.c to en.h.
   MLX5E_HW2SW_MTU is also moved to en.h for symmetric reason
   but it is not a must.

v2:
- Keep the xdp specific logic in mlx5e_xdp_handle()
- Update dma_len after the sanity checks in mlx5e_xmit_xdp_frame()

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Martin KaFai Lau 2017-01-17 22:06:07 -08:00 committed by David S. Miller
parent 0e40f4c959
commit d8bec2b29a
3 changed files with 40 additions and 29 deletions

View File

@ -51,6 +51,9 @@
#define MLX5_SET_CFG(p, f, v) MLX5_SET(create_flow_group_in, p, f, v)
#define MLX5E_HW2SW_MTU(hwmtu) ((hwmtu) - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN))
#define MLX5E_SW2HW_MTU(swmtu) ((swmtu) + (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN))
#define MLX5E_MAX_NUM_TC 8
#define MLX5E_PARAMS_MINIMUM_LOG_SQ_SIZE 0x6
@ -369,6 +372,7 @@ struct mlx5e_rq {
unsigned long state;
int ix;
u16 rx_headroom;
struct mlx5e_rx_am am; /* Adaptive Moderation */
struct bpf_prog *xdp_prog;

View File

@ -343,9 +343,6 @@ static void mlx5e_disable_async_events(struct mlx5e_priv *priv)
synchronize_irq(mlx5_get_msix_vec(priv->mdev, MLX5_EQ_VEC_ASYNC));
}
#define MLX5E_HW2SW_MTU(hwmtu) (hwmtu - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN))
#define MLX5E_SW2HW_MTU(swmtu) (swmtu + (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN))
static inline int mlx5e_get_wqe_mtt_sz(void)
{
/* UMR copies MTTs in units of MLX5_UMR_MTT_ALIGNMENT bytes.
@ -534,9 +531,13 @@ static int mlx5e_create_rq(struct mlx5e_channel *c,
goto err_rq_wq_destroy;
}
rq->buff.map_dir = DMA_FROM_DEVICE;
if (rq->xdp_prog)
if (rq->xdp_prog) {
rq->buff.map_dir = DMA_BIDIRECTIONAL;
rq->rx_headroom = XDP_PACKET_HEADROOM;
} else {
rq->buff.map_dir = DMA_FROM_DEVICE;
rq->rx_headroom = MLX5_RX_HEADROOM;
}
switch (priv->params.rq_wq_type) {
case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ:
@ -586,7 +587,7 @@ static int mlx5e_create_rq(struct mlx5e_channel *c,
byte_count = rq->buff.wqe_sz;
/* calc the required page order */
frag_sz = MLX5_RX_HEADROOM +
frag_sz = rq->rx_headroom +
byte_count /* packet data */ +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
frag_sz = SKB_DATA_ALIGN(frag_sz);
@ -3153,11 +3154,6 @@ static int mlx5e_xdp_set(struct net_device *netdev, struct bpf_prog *prog)
bool reset, was_opened;
int i;
if (prog && prog->xdp_adjust_head) {
netdev_err(netdev, "Does not support bpf_xdp_adjust_head()\n");
return -EOPNOTSUPP;
}
mutex_lock(&priv->state_lock);
if ((netdev->features & NETIF_F_LRO) && prog) {

View File

@ -264,7 +264,7 @@ int mlx5e_alloc_rx_wqe(struct mlx5e_rq *rq, struct mlx5e_rx_wqe *wqe, u16 ix)
if (unlikely(mlx5e_page_alloc_mapped(rq, di)))
return -ENOMEM;
wqe->data.addr = cpu_to_be64(di->addr + MLX5_RX_HEADROOM);
wqe->data.addr = cpu_to_be64(di->addr + rq->rx_headroom);
return 0;
}
@ -646,8 +646,7 @@ static inline void mlx5e_xmit_xdp_doorbell(struct mlx5e_sq *sq)
static inline void mlx5e_xmit_xdp_frame(struct mlx5e_rq *rq,
struct mlx5e_dma_info *di,
unsigned int data_offset,
int len)
const struct xdp_buff *xdp)
{
struct mlx5e_sq *sq = &rq->channel->xdp_sq;
struct mlx5_wq_cyc *wq = &sq->wq;
@ -659,9 +658,16 @@ static inline void mlx5e_xmit_xdp_frame(struct mlx5e_rq *rq,
struct mlx5_wqe_eth_seg *eseg = &wqe->eth;
struct mlx5_wqe_data_seg *dseg;
ptrdiff_t data_offset = xdp->data - xdp->data_hard_start;
dma_addr_t dma_addr = di->addr + data_offset + MLX5E_XDP_MIN_INLINE;
unsigned int dma_len = len - MLX5E_XDP_MIN_INLINE;
void *data = page_address(di->page) + data_offset;
unsigned int dma_len = xdp->data_end - xdp->data;
if (unlikely(dma_len < MLX5E_XDP_MIN_INLINE ||
MLX5E_SW2HW_MTU(rq->netdev->mtu) < dma_len)) {
rq->stats.xdp_drop++;
mlx5e_page_release(rq, di, true);
return;
}
if (unlikely(!mlx5e_sq_has_room_for(sq, MLX5E_XDP_TX_WQEBBS))) {
if (sq->db.xdp.doorbell) {
@ -674,13 +680,14 @@ static inline void mlx5e_xmit_xdp_frame(struct mlx5e_rq *rq,
return;
}
dma_len -= MLX5E_XDP_MIN_INLINE;
dma_sync_single_for_device(sq->pdev, dma_addr, dma_len,
PCI_DMA_TODEVICE);
memset(wqe, 0, sizeof(*wqe));
/* copy the inline part */
memcpy(eseg->inline_hdr_start, data, MLX5E_XDP_MIN_INLINE);
memcpy(eseg->inline_hdr_start, xdp->data, MLX5E_XDP_MIN_INLINE);
eseg->inline_hdr_sz = cpu_to_be16(MLX5E_XDP_MIN_INLINE);
dseg = (struct mlx5_wqe_data_seg *)cseg + (MLX5E_XDP_TX_DS_COUNT - 1);
@ -703,25 +710,29 @@ static inline void mlx5e_xmit_xdp_frame(struct mlx5e_rq *rq,
}
/* returns true if packet was consumed by xdp */
static inline bool mlx5e_xdp_handle(struct mlx5e_rq *rq,
const struct bpf_prog *prog,
struct mlx5e_dma_info *di,
void *data, u16 len)
static inline int mlx5e_xdp_handle(struct mlx5e_rq *rq,
struct mlx5e_dma_info *di,
void *va, u16 *rx_headroom, u32 *len)
{
const struct bpf_prog *prog = READ_ONCE(rq->xdp_prog);
struct xdp_buff xdp;
u32 act;
if (!prog)
return false;
xdp.data = data;
xdp.data_end = xdp.data + len;
xdp.data = va + *rx_headroom;
xdp.data_end = xdp.data + *len;
xdp.data_hard_start = va;
act = bpf_prog_run_xdp(prog, &xdp);
switch (act) {
case XDP_PASS:
*rx_headroom = xdp.data - xdp.data_hard_start;
*len = xdp.data_end - xdp.data;
return false;
case XDP_TX:
mlx5e_xmit_xdp_frame(rq, di, MLX5_RX_HEADROOM, len);
mlx5e_xmit_xdp_frame(rq, di, &xdp);
return true;
default:
bpf_warn_invalid_xdp_action(act);
@ -740,15 +751,16 @@ struct sk_buff *skb_from_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe,
struct mlx5e_dma_info *di;
struct sk_buff *skb;
void *va, *data;
u16 rx_headroom = rq->rx_headroom;
bool consumed;
di = &rq->dma_info[wqe_counter];
va = page_address(di->page);
data = va + MLX5_RX_HEADROOM;
data = va + rx_headroom;
dma_sync_single_range_for_cpu(rq->pdev,
di->addr,
MLX5_RX_HEADROOM,
rx_headroom,
rq->buff.wqe_sz,
DMA_FROM_DEVICE);
prefetch(data);
@ -760,8 +772,7 @@ struct sk_buff *skb_from_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe,
}
rcu_read_lock();
consumed = mlx5e_xdp_handle(rq, READ_ONCE(rq->xdp_prog), di, data,
cqe_bcnt);
consumed = mlx5e_xdp_handle(rq, di, va, &rx_headroom, &cqe_bcnt);
rcu_read_unlock();
if (consumed)
return NULL; /* page/packet was consumed by XDP */
@ -777,7 +788,7 @@ struct sk_buff *skb_from_cqe(struct mlx5e_rq *rq, struct mlx5_cqe64 *cqe,
page_ref_inc(di->page);
mlx5e_page_release(rq, di, true);
skb_reserve(skb, MLX5_RX_HEADROOM);
skb_reserve(skb, rx_headroom);
skb_put(skb, cqe_bcnt);
return skb;