[Intel-wired-lan] [PATCH 1/3] i40e: Initial support for XDP
Björn Töpel
bjorn.topel at gmail.com
Thu Dec 8 17:00:20 UTC 2016
From: Björn Töpel <bjorn.topel at intel.com>
This commit adds basic XDP support for i40e derived NICs. All XDP
actions will end up in XDP_DROP.
Only the default/main VSI has support for enabling XDP.
Acked-by: John Fastabend <john.r.fastabend at intel.com>
Signed-off-by: Björn Töpel <bjorn.topel at intel.com>
---
drivers/net/ethernet/intel/i40e/i40e.h | 13 +++
drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 3 +
drivers/net/ethernet/intel/i40e/i40e_main.c | 74 +++++++++++++
drivers/net/ethernet/intel/i40e/i40e_txrx.c | 146 ++++++++++++++++++++-----
drivers/net/ethernet/intel/i40e/i40e_txrx.h | 2 +
5 files changed, 213 insertions(+), 25 deletions(-)
diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index ba8d30984bee..05d805f439e6 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -545,6 +545,8 @@ struct i40e_vsi {
struct i40e_ring **rx_rings;
struct i40e_ring **tx_rings;
+ struct bpf_prog *xdp_prog;
+
u32 active_filters;
u32 promisc_threshold;
@@ -904,4 +906,15 @@ i40e_status i40e_get_npar_bw_setting(struct i40e_pf *pf);
i40e_status i40e_set_npar_bw_setting(struct i40e_pf *pf);
i40e_status i40e_commit_npar_bw_setting(struct i40e_pf *pf);
void i40e_print_link_message(struct i40e_vsi *vsi, bool isup);
+
+/**
+ * i40e_enabled_xdp_vsi - Check if VSI has XDP enabled
+ * @vsi: pointer to a vsi
+ *
+ * Returns true if the VSI has XDP enabled.
+ **/
+static inline bool i40e_enabled_xdp_vsi(const struct i40e_vsi *vsi)
+{
+ return vsi->xdp_prog;
+}
#endif /* _I40E_H_ */
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index cc1465aac2ef..831bbc208fc8 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -1254,6 +1254,9 @@ static int i40e_set_ringparam(struct net_device *netdev,
if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
return -EINVAL;
+ if (i40e_enabled_xdp_vsi(vsi))
+ return -EINVAL;
+
if (ring->tx_pending > I40E_MAX_NUM_DESCRIPTORS ||
ring->tx_pending < I40E_MIN_NUM_DESCRIPTORS ||
ring->rx_pending > I40E_MAX_NUM_DESCRIPTORS ||
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index da4cbe32eb86..db0240213f3b 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -24,6 +24,7 @@
*
******************************************************************************/
+#include <linux/bpf.h>
#include <linux/etherdevice.h>
#include <linux/of_net.h>
#include <linux/pci.h>
@@ -2431,6 +2432,13 @@ static int i40e_change_mtu(struct net_device *netdev, int new_mtu)
struct i40e_netdev_priv *np = netdev_priv(netdev);
struct i40e_vsi *vsi = np->vsi;
+ if (i40e_enabled_xdp_vsi(vsi)) {
+ int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
+
+ if (max_frame > I40E_RXBUFFER_2048)
+ return -EINVAL;
+ }
+
netdev_info(netdev, "changing MTU from %d to %d\n",
netdev->mtu, new_mtu);
netdev->mtu = new_mtu;
@@ -3085,6 +3093,15 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring)
ring->tail = hw->hw_addr + I40E_QRX_TAIL(pf_q);
writel(0, ring->tail);
+ if (i40e_enabled_xdp_vsi(vsi)) {
+ struct bpf_prog *prog;
+
+ prog = bpf_prog_add(vsi->xdp_prog, 1);
+ if (IS_ERR(prog))
+ return PTR_ERR(prog);
+ ring->xdp_prog = prog;
+ }
+
i40e_alloc_rx_buffers(ring, I40E_DESC_UNUSED(ring));
return 0;
@@ -9234,6 +9251,62 @@ static netdev_features_t i40e_features_check(struct sk_buff *skb,
return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
}
+/**
+ * i40e_xdp_setup - Add/remove an XDP program to a VSI
+ * @vsi: the VSI to add the program
+ * @prog: the XDP program
+ **/
+static int i40e_xdp_setup(struct i40e_vsi *vsi,
+ struct bpf_prog *prog)
+{
+ struct i40e_pf *pf = vsi->back;
+ struct net_device *netdev = vsi->netdev;
+ int frame_size = netdev->mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
+
+ if (frame_size > I40E_RXBUFFER_2048)
+ return -EINVAL;
+
+ if (!(pf->flags & I40E_FLAG_MSIX_ENABLED))
+ return -EINVAL;
+
+ if (!i40e_enabled_xdp_vsi(vsi) && !prog)
+ return 0;
+
+ i40e_prep_for_reset(pf);
+
+ if (vsi->xdp_prog)
+ bpf_prog_put(vsi->xdp_prog);
+ vsi->xdp_prog = prog;
+
+ i40e_reset_and_rebuild(pf, true);
+ return 0;
+}
+
+/**
+ * i40e_xdp - NDO for enabled/query
+ * @dev: the netdev
+ * @xdp: XDP program
+ **/
+static int i40e_xdp(struct net_device *dev,
+ struct netdev_xdp *xdp)
+{
+ struct i40e_netdev_priv *np = netdev_priv(dev);
+ struct i40e_vsi *vsi = np->vsi;
+
+ if (vsi->type != I40E_VSI_MAIN)
+ return -EINVAL;
+
+ switch (xdp->command) {
+ case XDP_SETUP_PROG:
+ return i40e_xdp_setup(vsi, xdp->prog);
+ case XDP_QUERY_PROG:
+ xdp->prog_attached = i40e_enabled_xdp_vsi(vsi);
+ return 0;
+ default:
+ return -EINVAL;
+ }
+}
+
static const struct net_device_ops i40e_netdev_ops = {
.ndo_open = i40e_open,
.ndo_stop = i40e_close,
@@ -9270,6 +9343,7 @@ static const struct net_device_ops i40e_netdev_ops = {
.ndo_features_check = i40e_features_check,
.ndo_bridge_getlink = i40e_ndo_bridge_getlink,
.ndo_bridge_setlink = i40e_ndo_bridge_setlink,
+ .ndo_xdp = i40e_xdp,
};
/**
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 352cf7cd2ef4..d835a51dafa6 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -24,6 +24,7 @@
*
******************************************************************************/
+#include <linux/bpf.h>
#include <linux/prefetch.h>
#include <net/busy_poll.h>
#include "i40e.h"
@@ -1040,6 +1041,11 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
rx_ring->next_to_alloc = 0;
rx_ring->next_to_clean = 0;
rx_ring->next_to_use = 0;
+
+ if (rx_ring->xdp_prog) {
+ bpf_prog_put(rx_ring->xdp_prog);
+ rx_ring->xdp_prog = NULL;
+ }
}
/**
@@ -1600,30 +1606,104 @@ static bool i40e_add_rx_frag(struct i40e_ring *rx_ring,
}
/**
+ * i40e_run_xdp - Runs an XDP program for an Rx ring
+ * @rx_ring: Rx ring used for XDP
+ * @rx_buffer: current Rx buffer
+ * @rx_desc: current Rx descriptor
+ * @xdp_prog: the XDP program to run
+ *
+ * Returns true if the XDP program consumed the incoming frame. False
+ * means pass the frame to the good old stack.
+ **/
+static bool i40e_run_xdp(struct i40e_ring *rx_ring,
+ struct i40e_rx_buffer *rx_buffer,
+ union i40e_rx_desc *rx_desc,
+ struct bpf_prog *xdp_prog)
+{
+ u64 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
+ unsigned int size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
+ I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
+ struct xdp_buff xdp;
+ u32 xdp_action;
+
+ WARN_ON(!i40e_test_staterr(rx_desc,
+ BIT(I40E_RX_DESC_STATUS_EOF_SHIFT)));
+
+ xdp.data = page_address(rx_buffer->page) + rx_buffer->page_offset;
+ xdp.data_end = xdp.data + size;
+ xdp_action = bpf_prog_run_xdp(xdp_prog, &xdp);
+
+ switch (xdp_action) {
+ case XDP_PASS:
+ return false;
+ default:
+ bpf_warn_invalid_xdp_action(xdp_action);
+ case XDP_ABORTED:
+ case XDP_TX:
+ case XDP_DROP:
+ if (likely(!i40e_page_is_reserved(rx_buffer->page))) {
+ i40e_reuse_rx_page(rx_ring, rx_buffer);
+ rx_ring->rx_stats.page_reuse_count++;
+ break;
+ }
+
+ /* we are not reusing the buffer so unmap it */
+ dma_unmap_page(rx_ring->dev, rx_buffer->dma, PAGE_SIZE,
+ DMA_FROM_DEVICE);
+ __free_pages(rx_buffer->page, 0);
+ }
+
+ /* clear contents of buffer_info */
+ rx_buffer->page = NULL;
+ return true; /* Swallowed by XDP */
+}
+
+/**
* i40e_fetch_rx_buffer - Allocate skb and populate it
* @rx_ring: rx descriptor ring to transact packets on
* @rx_desc: descriptor containing info written by hardware
+ * @skb: The allocated skb, if any
*
- * This function allocates an skb on the fly, and populates it with the page
- * data from the current receive descriptor, taking care to set up the skb
- * correctly, as well as handling calling the page recycle function if
- * necessary.
+ * Unless XDP is enabled, this function allocates an skb on the fly,
+ * and populates it with the page data from the current receive
+ * descriptor, taking care to set up the skb correctly, as well as
+ * handling calling the page recycle function if necessary.
+ *
+ * If the received frame was handled by XDP, true is
+ * returned. Otherwise, the skb is returned to the caller via the skb
+ * parameter.
*/
static inline
-struct sk_buff *i40e_fetch_rx_buffer(struct i40e_ring *rx_ring,
- union i40e_rx_desc *rx_desc)
+bool i40e_fetch_rx_buffer(struct i40e_ring *rx_ring,
+ union i40e_rx_desc *rx_desc,
+ struct sk_buff **skb)
{
struct i40e_rx_buffer *rx_buffer;
- struct sk_buff *skb;
struct page *page;
rx_buffer = &rx_ring->rx_bi[rx_ring->next_to_clean];
page = rx_buffer->page;
prefetchw(page);
- skb = rx_buffer->skb;
+ /* we are reusing so sync this buffer for CPU use */
+ dma_sync_single_range_for_cpu(rx_ring->dev,
+ rx_buffer->dma,
+ rx_buffer->page_offset,
+ I40E_RXBUFFER_2048,
+ DMA_FROM_DEVICE);
+
+ if (rx_ring->xdp_prog) {
+ bool xdp_consumed;
+
+ xdp_consumed = i40e_run_xdp(rx_ring, rx_buffer,
+ rx_desc, rx_ring->xdp_prog);
+ if (xdp_consumed)
+ return true;
+ }
- if (likely(!skb)) {
+ *skb = rx_buffer->skb;
+
+ if (likely(!*skb)) {
void *page_addr = page_address(page) + rx_buffer->page_offset;
/* prefetch first cache line of first page */
@@ -1633,32 +1713,25 @@ struct sk_buff *i40e_fetch_rx_buffer(struct i40e_ring *rx_ring,
#endif
/* allocate a skb to store the frags */
- skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
- I40E_RX_HDR_SIZE,
- GFP_ATOMIC | __GFP_NOWARN);
- if (unlikely(!skb)) {
+ *skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
+ I40E_RX_HDR_SIZE,
+ GFP_ATOMIC | __GFP_NOWARN);
+ if (unlikely(!*skb)) {
rx_ring->rx_stats.alloc_buff_failed++;
- return NULL;
+ return false;
}
/* we will be copying header into skb->data in
* pskb_may_pull so it is in our interest to prefetch
* it now to avoid a possible cache miss
*/
- prefetchw(skb->data);
+ prefetchw((*skb)->data);
} else {
rx_buffer->skb = NULL;
}
- /* we are reusing so sync this buffer for CPU use */
- dma_sync_single_range_for_cpu(rx_ring->dev,
- rx_buffer->dma,
- rx_buffer->page_offset,
- I40E_RXBUFFER_2048,
- DMA_FROM_DEVICE);
-
/* pull page into skb */
- if (i40e_add_rx_frag(rx_ring, rx_buffer, rx_desc, skb)) {
+ if (i40e_add_rx_frag(rx_ring, rx_buffer, rx_desc, *skb)) {
/* hand second half of page back to the ring */
i40e_reuse_rx_page(rx_ring, rx_buffer);
rx_ring->rx_stats.page_reuse_count++;
@@ -1671,7 +1744,7 @@ struct sk_buff *i40e_fetch_rx_buffer(struct i40e_ring *rx_ring,
/* clear contents of buffer_info */
rx_buffer->page = NULL;
- return skb;
+ return false;
}
/**
@@ -1716,6 +1789,20 @@ static bool i40e_is_non_eop(struct i40e_ring *rx_ring,
}
/**
+ * i40e_update_rx_next_to_clean - Bumps the next-to-clean for an Rx ing
+ * @rx_ring: Rx ring to bump
+ **/
+static void i40e_update_rx_next_to_clean(struct i40e_ring *rx_ring)
+{
+ u32 ntc = rx_ring->next_to_clean + 1;
+
+ ntc = (ntc < rx_ring->count) ? ntc : 0;
+ rx_ring->next_to_clean = ntc;
+
+ prefetch(I40E_RX_DESC(rx_ring, ntc));
+}
+
+/**
* i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
* @rx_ring: rx descriptor ring to transact packets on
* @budget: Total limit on number of packets to process
@@ -1739,6 +1826,7 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
u16 vlan_tag;
u8 rx_ptype;
u64 qword;
+ bool xdp_consumed;
/* return some buffers to hardware, one at a time is too slow */
if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
@@ -1764,7 +1852,15 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
*/
dma_rmb();
- skb = i40e_fetch_rx_buffer(rx_ring, rx_desc);
+ xdp_consumed = i40e_fetch_rx_buffer(rx_ring, rx_desc, &skb);
+ if (xdp_consumed) {
+ cleaned_count++;
+
+ i40e_update_rx_next_to_clean(rx_ring);
+ total_rx_packets++;
+ continue;
+ }
+
if (!skb)
break;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index e065321ce8ed..957d856a82c4 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -341,6 +341,8 @@ struct i40e_ring {
struct rcu_head rcu; /* to avoid race on free */
u16 next_to_alloc;
+
+ struct bpf_prog *xdp_prog;
} ____cacheline_internodealigned_in_smp;
enum i40e_latency_range {
--
2.9.3
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