[PATCH net-next] net: thunderx: Add support for xdp redirect
From: Jesper Dangaard Brouer <hidden>
Date: 2017-12-11 12:09:28
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lkml, netdev
On Fri, 24 Nov 2017 15:03:26 +0300 Aleksey Makarov [off-list ref] wrote:
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From: Sunil Goutham <redacted> This patch adds support for XDP_REDIRECT. Flush is not yet supported. Signed-off-by: Sunil Goutham <redacted> Signed-off-by: cjacob <redacted> Signed-off-by: Aleksey Makarov <redacted> --- drivers/net/ethernet/cavium/thunder/nicvf_main.c | 110 ++++++++++++++++----- drivers/net/ethernet/cavium/thunder/nicvf_queues.c | 11 ++- drivers/net/ethernet/cavium/thunder/nicvf_queues.h | 4 + 3 files changed, 94 insertions(+), 31 deletions(-)diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c index a063c36c4c58..b82e28262c57 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c +++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c@@ -65,6 +65,11 @@ module_param(cpi_alg, int, S_IRUGO); MODULE_PARM_DESC(cpi_alg, "PFC algorithm (0=none, 1=VLAN, 2=VLAN16, 3=IP Diffserv)"); +struct nicvf_xdp_tx { + u64 dma_addr; + u8 qidx; +}; +
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static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog, struct cqe_rx_t *cqe_rx, struct snd_queue *sq, struct sk_buff **skb) { struct xdp_buff xdp; struct page *page; + struct nicvf_xdp_tx *xdp_tx = NULL; u32 action; - u16 len, offset = 0; + u16 len, err, offset = 0; u64 dma_addr, cpu_addr; void *orig_data;@@ -521,7 +541,7 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog, cpu_addr = (u64)phys_to_virt(cpu_addr); page = virt_to_page((void *)cpu_addr); - xdp.data_hard_start = page_address(page); + xdp.data_hard_start = page_address(page) + RCV_BUF_HEADROOM; xdp.data = (void *)cpu_addr; xdp_set_data_meta_invalid(&xdp); xdp.data_end = xdp.data + len;
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@@ -564,6 +573,20 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog, case XDP_TX: nicvf_xdp_sq_append_pkt(nic, sq, (u64)xdp.data, dma_addr, len); return true; + case XDP_REDIRECT: + /* Save DMA address for use while transmitting */ + xdp_tx = (struct nicvf_xdp_tx *)page_address(page); + xdp_tx->dma_addr = dma_addr; + xdp_tx->qidx = nicvf_netdev_qidx(nic, cqe_rx->rq_idx);
Hey, this sucks... You cannot just invent your own in-driver usage of the XDP packet headroom. That is specific to your driver only. In effect you can only XDP_REDIRECT from your driver out your own driver. The XDP_TX action is for driver/port local redirect. The XDP_REDIRECT action is between drivers.
+ + err = xdp_do_redirect(nic->pnicvf->netdev, &xdp, prog); + if (!err) + return true; + + /* Free the page on error */ + nicvf_unmap_page(nic, page, dma_addr); + put_page(page); + break; default: bpf_warn_invalid_xdp_action(action); /* fall through */
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@@ -1764,6 +1776,50 @@ static int nicvf_xdp(struct net_device *netdev, struct netdev_bpf *xdp) } } +static int nicvf_xdp_xmit(struct net_device *netdev, struct xdp_buff *xdp)
This is a generic ndo_xdp_xmit that other drivers can call.
+{
+ struct nicvf *nic = netdev_priv(netdev);
+ struct nicvf *snic = nic;
+ struct nicvf_xdp_tx *xdp_tx;
+ struct snd_queue *sq;
+ struct page *page;
+ int err, qidx;
+
+ if (!netif_running(netdev) || !nic->xdp_prog)
+ return -EINVAL;
+
+ page = virt_to_page(xdp->data);
+ xdp_tx = (struct nicvf_xdp_tx *)page_address(page);
+ qidx = xdp_tx->qidx;What is another driver XDP_REDIRECT a frame to your driver?
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+ + if (xdp_tx->qidx >= nic->xdp_tx_queues) + return -EINVAL; + + /* Get secondary Qset's info */ + if (xdp_tx->qidx >= MAX_SND_QUEUES_PER_QS) { + qidx = xdp_tx->qidx / MAX_SND_QUEUES_PER_QS; + snic = (struct nicvf *)nic->snicvf[qidx - 1]; + if (!snic) + return -EINVAL; + qidx = xdp_tx->qidx % MAX_SND_QUEUES_PER_QS; + } + + sq = &snic->qs->sq[qidx]; + err = nicvf_xdp_sq_append_pkt(snic, sq, (u64)xdp->data, + xdp_tx->dma_addr, + xdp->data_end - xdp->data); + if (err) + return -ENOMEM; + + nicvf_xdp_sq_doorbell(snic, sq, qidx); + return 0; +} + +static void nicvf_xdp_flush(struct net_device *dev) +{ + return; +} + static const struct net_device_ops nicvf_netdev_ops = { .ndo_open = nicvf_open, .ndo_stop = nicvf_stop,@@ -1775,6 +1831,8 @@ static const struct net_device_ops nicvf_netdev_ops = { .ndo_fix_features = nicvf_fix_features, .ndo_set_features = nicvf_set_features, .ndo_bpf = nicvf_xdp, + .ndo_xdp_xmit = nicvf_xdp_xmit, + .ndo_xdp_flush = nicvf_xdp_flush, };
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diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h index 67d1a3230773..178ab6e8e3c5 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h +++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h@@ -11,6 +11,7 @@ #include <linux/netdevice.h> #include <linux/iommu.h> +#include <linux/bpf.h> #include "q_struct.h" #define MAX_QUEUE_SET 128@@ -92,6 +93,9 @@ #define RCV_FRAG_LEN (SKB_DATA_ALIGN(DMA_BUFFER_LEN + NET_SKB_PAD) + \ SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) +#define RCV_BUF_HEADROOM 128 /* To store dma address for XDP redirect */ +#define XDP_HEADROOM (XDP_PACKET_HEADROOM + RCV_BUF_HEADROOM) + #define MAX_CQES_FOR_TX ((SND_QUEUE_LEN / MIN_SQ_DESC_PER_PKT_XMIT) * \ MAX_CQE_PER_PKT_XMIT)
-- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer