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-rw-r--r--drivers/net/veth.c1908
1 files changed, 1908 insertions, 0 deletions
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
new file mode 100644
index 000000000..36c5a41f8
--- /dev/null
+++ b/drivers/net/veth.c
@@ -0,0 +1,1908 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * drivers/net/veth.c
+ *
+ * Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc
+ *
+ * Author: Pavel Emelianov <xemul@openvz.org>
+ * Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com>
+ *
+ */
+
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <linux/ethtool.h>
+#include <linux/etherdevice.h>
+#include <linux/u64_stats_sync.h>
+
+#include <net/rtnetlink.h>
+#include <net/dst.h>
+#include <net/xfrm.h>
+#include <net/xdp.h>
+#include <linux/veth.h>
+#include <linux/module.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include <linux/ptr_ring.h>
+#include <linux/bpf_trace.h>
+#include <linux/net_tstamp.h>
+
+#define DRV_NAME "veth"
+#define DRV_VERSION "1.0"
+
+#define VETH_XDP_FLAG BIT(0)
+#define VETH_RING_SIZE 256
+#define VETH_XDP_HEADROOM (XDP_PACKET_HEADROOM + NET_IP_ALIGN)
+
+#define VETH_XDP_TX_BULK_SIZE 16
+#define VETH_XDP_BATCH 16
+
+struct veth_stats {
+ u64 rx_drops;
+ /* xdp */
+ u64 xdp_packets;
+ u64 xdp_bytes;
+ u64 xdp_redirect;
+ u64 xdp_drops;
+ u64 xdp_tx;
+ u64 xdp_tx_err;
+ u64 peer_tq_xdp_xmit;
+ u64 peer_tq_xdp_xmit_err;
+};
+
+struct veth_rq_stats {
+ struct veth_stats vs;
+ struct u64_stats_sync syncp;
+};
+
+struct veth_rq {
+ struct napi_struct xdp_napi;
+ struct napi_struct __rcu *napi; /* points to xdp_napi when the latter is initialized */
+ struct net_device *dev;
+ struct bpf_prog __rcu *xdp_prog;
+ struct xdp_mem_info xdp_mem;
+ struct veth_rq_stats stats;
+ bool rx_notify_masked;
+ struct ptr_ring xdp_ring;
+ struct xdp_rxq_info xdp_rxq;
+};
+
+struct veth_priv {
+ struct net_device __rcu *peer;
+ atomic64_t dropped;
+ struct bpf_prog *_xdp_prog;
+ struct veth_rq *rq;
+ unsigned int requested_headroom;
+};
+
+struct veth_xdp_tx_bq {
+ struct xdp_frame *q[VETH_XDP_TX_BULK_SIZE];
+ unsigned int count;
+};
+
+/*
+ * ethtool interface
+ */
+
+struct veth_q_stat_desc {
+ char desc[ETH_GSTRING_LEN];
+ size_t offset;
+};
+
+#define VETH_RQ_STAT(m) offsetof(struct veth_stats, m)
+
+static const struct veth_q_stat_desc veth_rq_stats_desc[] = {
+ { "xdp_packets", VETH_RQ_STAT(xdp_packets) },
+ { "xdp_bytes", VETH_RQ_STAT(xdp_bytes) },
+ { "drops", VETH_RQ_STAT(rx_drops) },
+ { "xdp_redirect", VETH_RQ_STAT(xdp_redirect) },
+ { "xdp_drops", VETH_RQ_STAT(xdp_drops) },
+ { "xdp_tx", VETH_RQ_STAT(xdp_tx) },
+ { "xdp_tx_errors", VETH_RQ_STAT(xdp_tx_err) },
+};
+
+#define VETH_RQ_STATS_LEN ARRAY_SIZE(veth_rq_stats_desc)
+
+static const struct veth_q_stat_desc veth_tq_stats_desc[] = {
+ { "xdp_xmit", VETH_RQ_STAT(peer_tq_xdp_xmit) },
+ { "xdp_xmit_errors", VETH_RQ_STAT(peer_tq_xdp_xmit_err) },
+};
+
+#define VETH_TQ_STATS_LEN ARRAY_SIZE(veth_tq_stats_desc)
+
+static struct {
+ const char string[ETH_GSTRING_LEN];
+} ethtool_stats_keys[] = {
+ { "peer_ifindex" },
+};
+
+static int veth_get_link_ksettings(struct net_device *dev,
+ struct ethtool_link_ksettings *cmd)
+{
+ cmd->base.speed = SPEED_10000;
+ cmd->base.duplex = DUPLEX_FULL;
+ cmd->base.port = PORT_TP;
+ cmd->base.autoneg = AUTONEG_DISABLE;
+ return 0;
+}
+
+static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
+{
+ strscpy(info->driver, DRV_NAME, sizeof(info->driver));
+ strscpy(info->version, DRV_VERSION, sizeof(info->version));
+}
+
+static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
+{
+ u8 *p = buf;
+ int i, j;
+
+ switch(stringset) {
+ case ETH_SS_STATS:
+ memcpy(p, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
+ p += sizeof(ethtool_stats_keys);
+ for (i = 0; i < dev->real_num_rx_queues; i++)
+ for (j = 0; j < VETH_RQ_STATS_LEN; j++)
+ ethtool_sprintf(&p, "rx_queue_%u_%.18s",
+ i, veth_rq_stats_desc[j].desc);
+
+ for (i = 0; i < dev->real_num_tx_queues; i++)
+ for (j = 0; j < VETH_TQ_STATS_LEN; j++)
+ ethtool_sprintf(&p, "tx_queue_%u_%.18s",
+ i, veth_tq_stats_desc[j].desc);
+ break;
+ }
+}
+
+static int veth_get_sset_count(struct net_device *dev, int sset)
+{
+ switch (sset) {
+ case ETH_SS_STATS:
+ return ARRAY_SIZE(ethtool_stats_keys) +
+ VETH_RQ_STATS_LEN * dev->real_num_rx_queues +
+ VETH_TQ_STATS_LEN * dev->real_num_tx_queues;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static void veth_get_ethtool_stats(struct net_device *dev,
+ struct ethtool_stats *stats, u64 *data)
+{
+ struct veth_priv *rcv_priv, *priv = netdev_priv(dev);
+ struct net_device *peer = rtnl_dereference(priv->peer);
+ int i, j, idx;
+
+ data[0] = peer ? peer->ifindex : 0;
+ idx = 1;
+ for (i = 0; i < dev->real_num_rx_queues; i++) {
+ const struct veth_rq_stats *rq_stats = &priv->rq[i].stats;
+ const void *stats_base = (void *)&rq_stats->vs;
+ unsigned int start;
+ size_t offset;
+
+ do {
+ start = u64_stats_fetch_begin_irq(&rq_stats->syncp);
+ for (j = 0; j < VETH_RQ_STATS_LEN; j++) {
+ offset = veth_rq_stats_desc[j].offset;
+ data[idx + j] = *(u64 *)(stats_base + offset);
+ }
+ } while (u64_stats_fetch_retry_irq(&rq_stats->syncp, start));
+ idx += VETH_RQ_STATS_LEN;
+ }
+
+ if (!peer)
+ return;
+
+ rcv_priv = netdev_priv(peer);
+ for (i = 0; i < peer->real_num_rx_queues; i++) {
+ const struct veth_rq_stats *rq_stats = &rcv_priv->rq[i].stats;
+ const void *base = (void *)&rq_stats->vs;
+ unsigned int start, tx_idx = idx;
+ size_t offset;
+
+ tx_idx += (i % dev->real_num_tx_queues) * VETH_TQ_STATS_LEN;
+ do {
+ start = u64_stats_fetch_begin_irq(&rq_stats->syncp);
+ for (j = 0; j < VETH_TQ_STATS_LEN; j++) {
+ offset = veth_tq_stats_desc[j].offset;
+ data[tx_idx + j] += *(u64 *)(base + offset);
+ }
+ } while (u64_stats_fetch_retry_irq(&rq_stats->syncp, start));
+ }
+}
+
+static void veth_get_channels(struct net_device *dev,
+ struct ethtool_channels *channels)
+{
+ channels->tx_count = dev->real_num_tx_queues;
+ channels->rx_count = dev->real_num_rx_queues;
+ channels->max_tx = dev->num_tx_queues;
+ channels->max_rx = dev->num_rx_queues;
+}
+
+static int veth_set_channels(struct net_device *dev,
+ struct ethtool_channels *ch);
+
+static const struct ethtool_ops veth_ethtool_ops = {
+ .get_drvinfo = veth_get_drvinfo,
+ .get_link = ethtool_op_get_link,
+ .get_strings = veth_get_strings,
+ .get_sset_count = veth_get_sset_count,
+ .get_ethtool_stats = veth_get_ethtool_stats,
+ .get_link_ksettings = veth_get_link_ksettings,
+ .get_ts_info = ethtool_op_get_ts_info,
+ .get_channels = veth_get_channels,
+ .set_channels = veth_set_channels,
+};
+
+/* general routines */
+
+static bool veth_is_xdp_frame(void *ptr)
+{
+ return (unsigned long)ptr & VETH_XDP_FLAG;
+}
+
+static struct xdp_frame *veth_ptr_to_xdp(void *ptr)
+{
+ return (void *)((unsigned long)ptr & ~VETH_XDP_FLAG);
+}
+
+static void *veth_xdp_to_ptr(struct xdp_frame *xdp)
+{
+ return (void *)((unsigned long)xdp | VETH_XDP_FLAG);
+}
+
+static void veth_ptr_free(void *ptr)
+{
+ if (veth_is_xdp_frame(ptr))
+ xdp_return_frame(veth_ptr_to_xdp(ptr));
+ else
+ kfree_skb(ptr);
+}
+
+static void __veth_xdp_flush(struct veth_rq *rq)
+{
+ /* Write ptr_ring before reading rx_notify_masked */
+ smp_mb();
+ if (!READ_ONCE(rq->rx_notify_masked) &&
+ napi_schedule_prep(&rq->xdp_napi)) {
+ WRITE_ONCE(rq->rx_notify_masked, true);
+ __napi_schedule(&rq->xdp_napi);
+ }
+}
+
+static int veth_xdp_rx(struct veth_rq *rq, struct sk_buff *skb)
+{
+ if (unlikely(ptr_ring_produce(&rq->xdp_ring, skb))) {
+ dev_kfree_skb_any(skb);
+ return NET_RX_DROP;
+ }
+
+ return NET_RX_SUCCESS;
+}
+
+static int veth_forward_skb(struct net_device *dev, struct sk_buff *skb,
+ struct veth_rq *rq, bool xdp)
+{
+ return __dev_forward_skb(dev, skb) ?: xdp ?
+ veth_xdp_rx(rq, skb) :
+ __netif_rx(skb);
+}
+
+/* return true if the specified skb has chances of GRO aggregation
+ * Don't strive for accuracy, but try to avoid GRO overhead in the most
+ * common scenarios.
+ * When XDP is enabled, all traffic is considered eligible, as the xmit
+ * device has TSO off.
+ * When TSO is enabled on the xmit device, we are likely interested only
+ * in UDP aggregation, explicitly check for that if the skb is suspected
+ * - the sock_wfree destructor is used by UDP, ICMP and XDP sockets -
+ * to belong to locally generated UDP traffic.
+ */
+static bool veth_skb_is_eligible_for_gro(const struct net_device *dev,
+ const struct net_device *rcv,
+ const struct sk_buff *skb)
+{
+ return !(dev->features & NETIF_F_ALL_TSO) ||
+ (skb->destructor == sock_wfree &&
+ rcv->features & (NETIF_F_GRO_FRAGLIST | NETIF_F_GRO_UDP_FWD));
+}
+
+static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct veth_priv *rcv_priv, *priv = netdev_priv(dev);
+ struct veth_rq *rq = NULL;
+ int ret = NETDEV_TX_OK;
+ struct net_device *rcv;
+ int length = skb->len;
+ bool use_napi = false;
+ int rxq;
+
+ rcu_read_lock();
+ rcv = rcu_dereference(priv->peer);
+ if (unlikely(!rcv) || !pskb_may_pull(skb, ETH_HLEN)) {
+ kfree_skb(skb);
+ goto drop;
+ }
+
+ rcv_priv = netdev_priv(rcv);
+ rxq = skb_get_queue_mapping(skb);
+ if (rxq < rcv->real_num_rx_queues) {
+ rq = &rcv_priv->rq[rxq];
+
+ /* The napi pointer is available when an XDP program is
+ * attached or when GRO is enabled
+ * Don't bother with napi/GRO if the skb can't be aggregated
+ */
+ use_napi = rcu_access_pointer(rq->napi) &&
+ veth_skb_is_eligible_for_gro(dev, rcv, skb);
+ }
+
+ skb_tx_timestamp(skb);
+ if (likely(veth_forward_skb(rcv, skb, rq, use_napi) == NET_RX_SUCCESS)) {
+ if (!use_napi)
+ dev_lstats_add(dev, length);
+ } else {
+drop:
+ atomic64_inc(&priv->dropped);
+ ret = NET_XMIT_DROP;
+ }
+
+ if (use_napi)
+ __veth_xdp_flush(rq);
+
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static u64 veth_stats_tx(struct net_device *dev, u64 *packets, u64 *bytes)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+
+ dev_lstats_read(dev, packets, bytes);
+ return atomic64_read(&priv->dropped);
+}
+
+static void veth_stats_rx(struct veth_stats *result, struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int i;
+
+ result->peer_tq_xdp_xmit_err = 0;
+ result->xdp_packets = 0;
+ result->xdp_tx_err = 0;
+ result->xdp_bytes = 0;
+ result->rx_drops = 0;
+ for (i = 0; i < dev->num_rx_queues; i++) {
+ u64 packets, bytes, drops, xdp_tx_err, peer_tq_xdp_xmit_err;
+ struct veth_rq_stats *stats = &priv->rq[i].stats;
+ unsigned int start;
+
+ do {
+ start = u64_stats_fetch_begin_irq(&stats->syncp);
+ peer_tq_xdp_xmit_err = stats->vs.peer_tq_xdp_xmit_err;
+ xdp_tx_err = stats->vs.xdp_tx_err;
+ packets = stats->vs.xdp_packets;
+ bytes = stats->vs.xdp_bytes;
+ drops = stats->vs.rx_drops;
+ } while (u64_stats_fetch_retry_irq(&stats->syncp, start));
+ result->peer_tq_xdp_xmit_err += peer_tq_xdp_xmit_err;
+ result->xdp_tx_err += xdp_tx_err;
+ result->xdp_packets += packets;
+ result->xdp_bytes += bytes;
+ result->rx_drops += drops;
+ }
+}
+
+static void veth_get_stats64(struct net_device *dev,
+ struct rtnl_link_stats64 *tot)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ struct net_device *peer;
+ struct veth_stats rx;
+ u64 packets, bytes;
+
+ tot->tx_dropped = veth_stats_tx(dev, &packets, &bytes);
+ tot->tx_bytes = bytes;
+ tot->tx_packets = packets;
+
+ veth_stats_rx(&rx, dev);
+ tot->tx_dropped += rx.xdp_tx_err;
+ tot->rx_dropped = rx.rx_drops + rx.peer_tq_xdp_xmit_err;
+ tot->rx_bytes = rx.xdp_bytes;
+ tot->rx_packets = rx.xdp_packets;
+
+ rcu_read_lock();
+ peer = rcu_dereference(priv->peer);
+ if (peer) {
+ veth_stats_tx(peer, &packets, &bytes);
+ tot->rx_bytes += bytes;
+ tot->rx_packets += packets;
+
+ veth_stats_rx(&rx, peer);
+ tot->tx_dropped += rx.peer_tq_xdp_xmit_err;
+ tot->rx_dropped += rx.xdp_tx_err;
+ tot->tx_bytes += rx.xdp_bytes;
+ tot->tx_packets += rx.xdp_packets;
+ }
+ rcu_read_unlock();
+}
+
+/* fake multicast ability */
+static void veth_set_multicast_list(struct net_device *dev)
+{
+}
+
+static int veth_select_rxq(struct net_device *dev)
+{
+ return smp_processor_id() % dev->real_num_rx_queues;
+}
+
+static struct net_device *veth_peer_dev(struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+
+ /* Callers must be under RCU read side. */
+ return rcu_dereference(priv->peer);
+}
+
+static int veth_xdp_xmit(struct net_device *dev, int n,
+ struct xdp_frame **frames,
+ u32 flags, bool ndo_xmit)
+{
+ struct veth_priv *rcv_priv, *priv = netdev_priv(dev);
+ int i, ret = -ENXIO, nxmit = 0;
+ struct net_device *rcv;
+ unsigned int max_len;
+ struct veth_rq *rq;
+
+ if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
+ return -EINVAL;
+
+ rcu_read_lock();
+ rcv = rcu_dereference(priv->peer);
+ if (unlikely(!rcv))
+ goto out;
+
+ rcv_priv = netdev_priv(rcv);
+ rq = &rcv_priv->rq[veth_select_rxq(rcv)];
+ /* The napi pointer is set if NAPI is enabled, which ensures that
+ * xdp_ring is initialized on receive side and the peer device is up.
+ */
+ if (!rcu_access_pointer(rq->napi))
+ goto out;
+
+ max_len = rcv->mtu + rcv->hard_header_len + VLAN_HLEN;
+
+ spin_lock(&rq->xdp_ring.producer_lock);
+ for (i = 0; i < n; i++) {
+ struct xdp_frame *frame = frames[i];
+ void *ptr = veth_xdp_to_ptr(frame);
+
+ if (unlikely(xdp_get_frame_len(frame) > max_len ||
+ __ptr_ring_produce(&rq->xdp_ring, ptr)))
+ break;
+ nxmit++;
+ }
+ spin_unlock(&rq->xdp_ring.producer_lock);
+
+ if (flags & XDP_XMIT_FLUSH)
+ __veth_xdp_flush(rq);
+
+ ret = nxmit;
+ if (ndo_xmit) {
+ u64_stats_update_begin(&rq->stats.syncp);
+ rq->stats.vs.peer_tq_xdp_xmit += nxmit;
+ rq->stats.vs.peer_tq_xdp_xmit_err += n - nxmit;
+ u64_stats_update_end(&rq->stats.syncp);
+ }
+
+out:
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static int veth_ndo_xdp_xmit(struct net_device *dev, int n,
+ struct xdp_frame **frames, u32 flags)
+{
+ int err;
+
+ err = veth_xdp_xmit(dev, n, frames, flags, true);
+ if (err < 0) {
+ struct veth_priv *priv = netdev_priv(dev);
+
+ atomic64_add(n, &priv->dropped);
+ }
+
+ return err;
+}
+
+static void veth_xdp_flush_bq(struct veth_rq *rq, struct veth_xdp_tx_bq *bq)
+{
+ int sent, i, err = 0, drops;
+
+ sent = veth_xdp_xmit(rq->dev, bq->count, bq->q, 0, false);
+ if (sent < 0) {
+ err = sent;
+ sent = 0;
+ }
+
+ for (i = sent; unlikely(i < bq->count); i++)
+ xdp_return_frame(bq->q[i]);
+
+ drops = bq->count - sent;
+ trace_xdp_bulk_tx(rq->dev, sent, drops, err);
+
+ u64_stats_update_begin(&rq->stats.syncp);
+ rq->stats.vs.xdp_tx += sent;
+ rq->stats.vs.xdp_tx_err += drops;
+ u64_stats_update_end(&rq->stats.syncp);
+
+ bq->count = 0;
+}
+
+static void veth_xdp_flush(struct veth_rq *rq, struct veth_xdp_tx_bq *bq)
+{
+ struct veth_priv *rcv_priv, *priv = netdev_priv(rq->dev);
+ struct net_device *rcv;
+ struct veth_rq *rcv_rq;
+
+ rcu_read_lock();
+ veth_xdp_flush_bq(rq, bq);
+ rcv = rcu_dereference(priv->peer);
+ if (unlikely(!rcv))
+ goto out;
+
+ rcv_priv = netdev_priv(rcv);
+ rcv_rq = &rcv_priv->rq[veth_select_rxq(rcv)];
+ /* xdp_ring is initialized on receive side? */
+ if (unlikely(!rcu_access_pointer(rcv_rq->xdp_prog)))
+ goto out;
+
+ __veth_xdp_flush(rcv_rq);
+out:
+ rcu_read_unlock();
+}
+
+static int veth_xdp_tx(struct veth_rq *rq, struct xdp_buff *xdp,
+ struct veth_xdp_tx_bq *bq)
+{
+ struct xdp_frame *frame = xdp_convert_buff_to_frame(xdp);
+
+ if (unlikely(!frame))
+ return -EOVERFLOW;
+
+ if (unlikely(bq->count == VETH_XDP_TX_BULK_SIZE))
+ veth_xdp_flush_bq(rq, bq);
+
+ bq->q[bq->count++] = frame;
+
+ return 0;
+}
+
+static struct xdp_frame *veth_xdp_rcv_one(struct veth_rq *rq,
+ struct xdp_frame *frame,
+ struct veth_xdp_tx_bq *bq,
+ struct veth_stats *stats)
+{
+ struct xdp_frame orig_frame;
+ struct bpf_prog *xdp_prog;
+
+ rcu_read_lock();
+ xdp_prog = rcu_dereference(rq->xdp_prog);
+ if (likely(xdp_prog)) {
+ struct xdp_buff xdp;
+ u32 act;
+
+ xdp_convert_frame_to_buff(frame, &xdp);
+ xdp.rxq = &rq->xdp_rxq;
+
+ act = bpf_prog_run_xdp(xdp_prog, &xdp);
+
+ switch (act) {
+ case XDP_PASS:
+ if (xdp_update_frame_from_buff(&xdp, frame))
+ goto err_xdp;
+ break;
+ case XDP_TX:
+ orig_frame = *frame;
+ xdp.rxq->mem = frame->mem;
+ if (unlikely(veth_xdp_tx(rq, &xdp, bq) < 0)) {
+ trace_xdp_exception(rq->dev, xdp_prog, act);
+ frame = &orig_frame;
+ stats->rx_drops++;
+ goto err_xdp;
+ }
+ stats->xdp_tx++;
+ rcu_read_unlock();
+ goto xdp_xmit;
+ case XDP_REDIRECT:
+ orig_frame = *frame;
+ xdp.rxq->mem = frame->mem;
+ if (xdp_do_redirect(rq->dev, &xdp, xdp_prog)) {
+ frame = &orig_frame;
+ stats->rx_drops++;
+ goto err_xdp;
+ }
+ stats->xdp_redirect++;
+ rcu_read_unlock();
+ goto xdp_xmit;
+ default:
+ bpf_warn_invalid_xdp_action(rq->dev, xdp_prog, act);
+ fallthrough;
+ case XDP_ABORTED:
+ trace_xdp_exception(rq->dev, xdp_prog, act);
+ fallthrough;
+ case XDP_DROP:
+ stats->xdp_drops++;
+ goto err_xdp;
+ }
+ }
+ rcu_read_unlock();
+
+ return frame;
+err_xdp:
+ rcu_read_unlock();
+ xdp_return_frame(frame);
+xdp_xmit:
+ return NULL;
+}
+
+/* frames array contains VETH_XDP_BATCH at most */
+static void veth_xdp_rcv_bulk_skb(struct veth_rq *rq, void **frames,
+ int n_xdpf, struct veth_xdp_tx_bq *bq,
+ struct veth_stats *stats)
+{
+ void *skbs[VETH_XDP_BATCH];
+ int i;
+
+ if (xdp_alloc_skb_bulk(skbs, n_xdpf,
+ GFP_ATOMIC | __GFP_ZERO) < 0) {
+ for (i = 0; i < n_xdpf; i++)
+ xdp_return_frame(frames[i]);
+ stats->rx_drops += n_xdpf;
+
+ return;
+ }
+
+ for (i = 0; i < n_xdpf; i++) {
+ struct sk_buff *skb = skbs[i];
+
+ skb = __xdp_build_skb_from_frame(frames[i], skb,
+ rq->dev);
+ if (!skb) {
+ xdp_return_frame(frames[i]);
+ stats->rx_drops++;
+ continue;
+ }
+ napi_gro_receive(&rq->xdp_napi, skb);
+ }
+}
+
+static void veth_xdp_get(struct xdp_buff *xdp)
+{
+ struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
+ int i;
+
+ get_page(virt_to_page(xdp->data));
+ if (likely(!xdp_buff_has_frags(xdp)))
+ return;
+
+ for (i = 0; i < sinfo->nr_frags; i++)
+ __skb_frag_ref(&sinfo->frags[i]);
+}
+
+static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq,
+ struct xdp_buff *xdp,
+ struct sk_buff **pskb)
+{
+ struct sk_buff *skb = *pskb;
+ u32 frame_sz;
+
+ if (skb_shared(skb) || skb_head_is_locked(skb) ||
+ skb_shinfo(skb)->nr_frags ||
+ skb_headroom(skb) < XDP_PACKET_HEADROOM) {
+ u32 size, len, max_head_size, off;
+ struct sk_buff *nskb;
+ struct page *page;
+ int i, head_off;
+
+ /* We need a private copy of the skb and data buffers since
+ * the ebpf program can modify it. We segment the original skb
+ * into order-0 pages without linearize it.
+ *
+ * Make sure we have enough space for linear and paged area
+ */
+ max_head_size = SKB_WITH_OVERHEAD(PAGE_SIZE -
+ VETH_XDP_HEADROOM);
+ if (skb->len > PAGE_SIZE * MAX_SKB_FRAGS + max_head_size)
+ goto drop;
+
+ /* Allocate skb head */
+ page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
+ if (!page)
+ goto drop;
+
+ nskb = build_skb(page_address(page), PAGE_SIZE);
+ if (!nskb) {
+ put_page(page);
+ goto drop;
+ }
+
+ skb_reserve(nskb, VETH_XDP_HEADROOM);
+ size = min_t(u32, skb->len, max_head_size);
+ if (skb_copy_bits(skb, 0, nskb->data, size)) {
+ consume_skb(nskb);
+ goto drop;
+ }
+ skb_put(nskb, size);
+
+ skb_copy_header(nskb, skb);
+ head_off = skb_headroom(nskb) - skb_headroom(skb);
+ skb_headers_offset_update(nskb, head_off);
+
+ /* Allocate paged area of new skb */
+ off = size;
+ len = skb->len - off;
+
+ for (i = 0; i < MAX_SKB_FRAGS && off < skb->len; i++) {
+ page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
+ if (!page) {
+ consume_skb(nskb);
+ goto drop;
+ }
+
+ size = min_t(u32, len, PAGE_SIZE);
+ skb_add_rx_frag(nskb, i, page, 0, size, PAGE_SIZE);
+ if (skb_copy_bits(skb, off, page_address(page),
+ size)) {
+ consume_skb(nskb);
+ goto drop;
+ }
+
+ len -= size;
+ off += size;
+ }
+
+ consume_skb(skb);
+ skb = nskb;
+ }
+
+ /* SKB "head" area always have tailroom for skb_shared_info */
+ frame_sz = skb_end_pointer(skb) - skb->head;
+ frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+ xdp_init_buff(xdp, frame_sz, &rq->xdp_rxq);
+ xdp_prepare_buff(xdp, skb->head, skb_headroom(skb),
+ skb_headlen(skb), true);
+
+ if (skb_is_nonlinear(skb)) {
+ skb_shinfo(skb)->xdp_frags_size = skb->data_len;
+ xdp_buff_set_frags_flag(xdp);
+ } else {
+ xdp_buff_clear_frags_flag(xdp);
+ }
+ *pskb = skb;
+
+ return 0;
+drop:
+ consume_skb(skb);
+ *pskb = NULL;
+
+ return -ENOMEM;
+}
+
+static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq,
+ struct sk_buff *skb,
+ struct veth_xdp_tx_bq *bq,
+ struct veth_stats *stats)
+{
+ void *orig_data, *orig_data_end;
+ struct bpf_prog *xdp_prog;
+ struct xdp_buff xdp;
+ u32 act, metalen;
+ int off;
+
+ skb_prepare_for_gro(skb);
+
+ rcu_read_lock();
+ xdp_prog = rcu_dereference(rq->xdp_prog);
+ if (unlikely(!xdp_prog)) {
+ rcu_read_unlock();
+ goto out;
+ }
+
+ __skb_push(skb, skb->data - skb_mac_header(skb));
+ if (veth_convert_skb_to_xdp_buff(rq, &xdp, &skb))
+ goto drop;
+
+ orig_data = xdp.data;
+ orig_data_end = xdp.data_end;
+
+ act = bpf_prog_run_xdp(xdp_prog, &xdp);
+
+ switch (act) {
+ case XDP_PASS:
+ break;
+ case XDP_TX:
+ veth_xdp_get(&xdp);
+ consume_skb(skb);
+ xdp.rxq->mem = rq->xdp_mem;
+ if (unlikely(veth_xdp_tx(rq, &xdp, bq) < 0)) {
+ trace_xdp_exception(rq->dev, xdp_prog, act);
+ stats->rx_drops++;
+ goto err_xdp;
+ }
+ stats->xdp_tx++;
+ rcu_read_unlock();
+ goto xdp_xmit;
+ case XDP_REDIRECT:
+ veth_xdp_get(&xdp);
+ consume_skb(skb);
+ xdp.rxq->mem = rq->xdp_mem;
+ if (xdp_do_redirect(rq->dev, &xdp, xdp_prog)) {
+ stats->rx_drops++;
+ goto err_xdp;
+ }
+ stats->xdp_redirect++;
+ rcu_read_unlock();
+ goto xdp_xmit;
+ default:
+ bpf_warn_invalid_xdp_action(rq->dev, xdp_prog, act);
+ fallthrough;
+ case XDP_ABORTED:
+ trace_xdp_exception(rq->dev, xdp_prog, act);
+ fallthrough;
+ case XDP_DROP:
+ stats->xdp_drops++;
+ goto xdp_drop;
+ }
+ rcu_read_unlock();
+
+ /* check if bpf_xdp_adjust_head was used */
+ off = orig_data - xdp.data;
+ if (off > 0)
+ __skb_push(skb, off);
+ else if (off < 0)
+ __skb_pull(skb, -off);
+
+ skb_reset_mac_header(skb);
+
+ /* check if bpf_xdp_adjust_tail was used */
+ off = xdp.data_end - orig_data_end;
+ if (off != 0)
+ __skb_put(skb, off); /* positive on grow, negative on shrink */
+
+ /* XDP frag metadata (e.g. nr_frags) are updated in eBPF helpers
+ * (e.g. bpf_xdp_adjust_tail), we need to update data_len here.
+ */
+ if (xdp_buff_has_frags(&xdp))
+ skb->data_len = skb_shinfo(skb)->xdp_frags_size;
+ else
+ skb->data_len = 0;
+
+ skb->protocol = eth_type_trans(skb, rq->dev);
+
+ metalen = xdp.data - xdp.data_meta;
+ if (metalen)
+ skb_metadata_set(skb, metalen);
+out:
+ return skb;
+drop:
+ stats->rx_drops++;
+xdp_drop:
+ rcu_read_unlock();
+ kfree_skb(skb);
+ return NULL;
+err_xdp:
+ rcu_read_unlock();
+ xdp_return_buff(&xdp);
+xdp_xmit:
+ return NULL;
+}
+
+static int veth_xdp_rcv(struct veth_rq *rq, int budget,
+ struct veth_xdp_tx_bq *bq,
+ struct veth_stats *stats)
+{
+ int i, done = 0, n_xdpf = 0;
+ void *xdpf[VETH_XDP_BATCH];
+
+ for (i = 0; i < budget; i++) {
+ void *ptr = __ptr_ring_consume(&rq->xdp_ring);
+
+ if (!ptr)
+ break;
+
+ if (veth_is_xdp_frame(ptr)) {
+ /* ndo_xdp_xmit */
+ struct xdp_frame *frame = veth_ptr_to_xdp(ptr);
+
+ stats->xdp_bytes += xdp_get_frame_len(frame);
+ frame = veth_xdp_rcv_one(rq, frame, bq, stats);
+ if (frame) {
+ /* XDP_PASS */
+ xdpf[n_xdpf++] = frame;
+ if (n_xdpf == VETH_XDP_BATCH) {
+ veth_xdp_rcv_bulk_skb(rq, xdpf, n_xdpf,
+ bq, stats);
+ n_xdpf = 0;
+ }
+ }
+ } else {
+ /* ndo_start_xmit */
+ struct sk_buff *skb = ptr;
+
+ stats->xdp_bytes += skb->len;
+ skb = veth_xdp_rcv_skb(rq, skb, bq, stats);
+ if (skb) {
+ if (skb_shared(skb) || skb_unclone(skb, GFP_ATOMIC))
+ netif_receive_skb(skb);
+ else
+ napi_gro_receive(&rq->xdp_napi, skb);
+ }
+ }
+ done++;
+ }
+
+ if (n_xdpf)
+ veth_xdp_rcv_bulk_skb(rq, xdpf, n_xdpf, bq, stats);
+
+ u64_stats_update_begin(&rq->stats.syncp);
+ rq->stats.vs.xdp_redirect += stats->xdp_redirect;
+ rq->stats.vs.xdp_bytes += stats->xdp_bytes;
+ rq->stats.vs.xdp_drops += stats->xdp_drops;
+ rq->stats.vs.rx_drops += stats->rx_drops;
+ rq->stats.vs.xdp_packets += done;
+ u64_stats_update_end(&rq->stats.syncp);
+
+ return done;
+}
+
+static int veth_poll(struct napi_struct *napi, int budget)
+{
+ struct veth_rq *rq =
+ container_of(napi, struct veth_rq, xdp_napi);
+ struct veth_stats stats = {};
+ struct veth_xdp_tx_bq bq;
+ int done;
+
+ bq.count = 0;
+
+ xdp_set_return_frame_no_direct();
+ done = veth_xdp_rcv(rq, budget, &bq, &stats);
+
+ if (stats.xdp_redirect > 0)
+ xdp_do_flush();
+
+ if (done < budget && napi_complete_done(napi, done)) {
+ /* Write rx_notify_masked before reading ptr_ring */
+ smp_store_mb(rq->rx_notify_masked, false);
+ if (unlikely(!__ptr_ring_empty(&rq->xdp_ring))) {
+ if (napi_schedule_prep(&rq->xdp_napi)) {
+ WRITE_ONCE(rq->rx_notify_masked, true);
+ __napi_schedule(&rq->xdp_napi);
+ }
+ }
+ }
+
+ if (stats.xdp_tx > 0)
+ veth_xdp_flush(rq, &bq);
+ xdp_clear_return_frame_no_direct();
+
+ return done;
+}
+
+static int __veth_napi_enable_range(struct net_device *dev, int start, int end)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int err, i;
+
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ err = ptr_ring_init(&rq->xdp_ring, VETH_RING_SIZE, GFP_KERNEL);
+ if (err)
+ goto err_xdp_ring;
+ }
+
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ napi_enable(&rq->xdp_napi);
+ rcu_assign_pointer(priv->rq[i].napi, &priv->rq[i].xdp_napi);
+ }
+
+ return 0;
+
+err_xdp_ring:
+ for (i--; i >= start; i--)
+ ptr_ring_cleanup(&priv->rq[i].xdp_ring, veth_ptr_free);
+
+ return err;
+}
+
+static int __veth_napi_enable(struct net_device *dev)
+{
+ return __veth_napi_enable_range(dev, 0, dev->real_num_rx_queues);
+}
+
+static void veth_napi_del_range(struct net_device *dev, int start, int end)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int i;
+
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ rcu_assign_pointer(priv->rq[i].napi, NULL);
+ napi_disable(&rq->xdp_napi);
+ __netif_napi_del(&rq->xdp_napi);
+ }
+ synchronize_net();
+
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ rq->rx_notify_masked = false;
+ ptr_ring_cleanup(&rq->xdp_ring, veth_ptr_free);
+ }
+}
+
+static void veth_napi_del(struct net_device *dev)
+{
+ veth_napi_del_range(dev, 0, dev->real_num_rx_queues);
+}
+
+static bool veth_gro_requested(const struct net_device *dev)
+{
+ return !!(dev->wanted_features & NETIF_F_GRO);
+}
+
+static int veth_enable_xdp_range(struct net_device *dev, int start, int end,
+ bool napi_already_on)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int err, i;
+
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ if (!napi_already_on)
+ netif_napi_add(dev, &rq->xdp_napi, veth_poll);
+ err = xdp_rxq_info_reg(&rq->xdp_rxq, dev, i, rq->xdp_napi.napi_id);
+ if (err < 0)
+ goto err_rxq_reg;
+
+ err = xdp_rxq_info_reg_mem_model(&rq->xdp_rxq,
+ MEM_TYPE_PAGE_SHARED,
+ NULL);
+ if (err < 0)
+ goto err_reg_mem;
+
+ /* Save original mem info as it can be overwritten */
+ rq->xdp_mem = rq->xdp_rxq.mem;
+ }
+ return 0;
+
+err_reg_mem:
+ xdp_rxq_info_unreg(&priv->rq[i].xdp_rxq);
+err_rxq_reg:
+ for (i--; i >= start; i--) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ xdp_rxq_info_unreg(&rq->xdp_rxq);
+ if (!napi_already_on)
+ netif_napi_del(&rq->xdp_napi);
+ }
+
+ return err;
+}
+
+static void veth_disable_xdp_range(struct net_device *dev, int start, int end,
+ bool delete_napi)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int i;
+
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ rq->xdp_rxq.mem = rq->xdp_mem;
+ xdp_rxq_info_unreg(&rq->xdp_rxq);
+
+ if (delete_napi)
+ netif_napi_del(&rq->xdp_napi);
+ }
+}
+
+static int veth_enable_xdp(struct net_device *dev)
+{
+ bool napi_already_on = veth_gro_requested(dev) && (dev->flags & IFF_UP);
+ struct veth_priv *priv = netdev_priv(dev);
+ int err, i;
+
+ if (!xdp_rxq_info_is_reg(&priv->rq[0].xdp_rxq)) {
+ err = veth_enable_xdp_range(dev, 0, dev->real_num_rx_queues, napi_already_on);
+ if (err)
+ return err;
+
+ if (!napi_already_on) {
+ err = __veth_napi_enable(dev);
+ if (err) {
+ veth_disable_xdp_range(dev, 0, dev->real_num_rx_queues, true);
+ return err;
+ }
+
+ if (!veth_gro_requested(dev)) {
+ /* user-space did not require GRO, but adding XDP
+ * is supposed to get GRO working
+ */
+ dev->features |= NETIF_F_GRO;
+ netdev_features_change(dev);
+ }
+ }
+ }
+
+ for (i = 0; i < dev->real_num_rx_queues; i++) {
+ rcu_assign_pointer(priv->rq[i].xdp_prog, priv->_xdp_prog);
+ rcu_assign_pointer(priv->rq[i].napi, &priv->rq[i].xdp_napi);
+ }
+
+ return 0;
+}
+
+static void veth_disable_xdp(struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int i;
+
+ for (i = 0; i < dev->real_num_rx_queues; i++)
+ rcu_assign_pointer(priv->rq[i].xdp_prog, NULL);
+
+ if (!netif_running(dev) || !veth_gro_requested(dev)) {
+ veth_napi_del(dev);
+
+ /* if user-space did not require GRO, since adding XDP
+ * enabled it, clear it now
+ */
+ if (!veth_gro_requested(dev) && netif_running(dev)) {
+ dev->features &= ~NETIF_F_GRO;
+ netdev_features_change(dev);
+ }
+ }
+
+ veth_disable_xdp_range(dev, 0, dev->real_num_rx_queues, false);
+}
+
+static int veth_napi_enable_range(struct net_device *dev, int start, int end)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int err, i;
+
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ netif_napi_add(dev, &rq->xdp_napi, veth_poll);
+ }
+
+ err = __veth_napi_enable_range(dev, start, end);
+ if (err) {
+ for (i = start; i < end; i++) {
+ struct veth_rq *rq = &priv->rq[i];
+
+ netif_napi_del(&rq->xdp_napi);
+ }
+ return err;
+ }
+ return err;
+}
+
+static int veth_napi_enable(struct net_device *dev)
+{
+ return veth_napi_enable_range(dev, 0, dev->real_num_rx_queues);
+}
+
+static void veth_disable_range_safe(struct net_device *dev, int start, int end)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+
+ if (start >= end)
+ return;
+
+ if (priv->_xdp_prog) {
+ veth_napi_del_range(dev, start, end);
+ veth_disable_xdp_range(dev, start, end, false);
+ } else if (veth_gro_requested(dev)) {
+ veth_napi_del_range(dev, start, end);
+ }
+}
+
+static int veth_enable_range_safe(struct net_device *dev, int start, int end)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int err;
+
+ if (start >= end)
+ return 0;
+
+ if (priv->_xdp_prog) {
+ /* these channels are freshly initialized, napi is not on there even
+ * when GRO is requeste
+ */
+ err = veth_enable_xdp_range(dev, start, end, false);
+ if (err)
+ return err;
+
+ err = __veth_napi_enable_range(dev, start, end);
+ if (err) {
+ /* on error always delete the newly added napis */
+ veth_disable_xdp_range(dev, start, end, true);
+ return err;
+ }
+ } else if (veth_gro_requested(dev)) {
+ return veth_napi_enable_range(dev, start, end);
+ }
+ return 0;
+}
+
+static int veth_set_channels(struct net_device *dev,
+ struct ethtool_channels *ch)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ unsigned int old_rx_count, new_rx_count;
+ struct veth_priv *peer_priv;
+ struct net_device *peer;
+ int err;
+
+ /* sanity check. Upper bounds are already enforced by the caller */
+ if (!ch->rx_count || !ch->tx_count)
+ return -EINVAL;
+
+ /* avoid braking XDP, if that is enabled */
+ peer = rtnl_dereference(priv->peer);
+ peer_priv = peer ? netdev_priv(peer) : NULL;
+ if (priv->_xdp_prog && peer && ch->rx_count < peer->real_num_tx_queues)
+ return -EINVAL;
+
+ if (peer && peer_priv && peer_priv->_xdp_prog && ch->tx_count > peer->real_num_rx_queues)
+ return -EINVAL;
+
+ old_rx_count = dev->real_num_rx_queues;
+ new_rx_count = ch->rx_count;
+ if (netif_running(dev)) {
+ /* turn device off */
+ netif_carrier_off(dev);
+ if (peer)
+ netif_carrier_off(peer);
+
+ /* try to allocate new resurces, as needed*/
+ err = veth_enable_range_safe(dev, old_rx_count, new_rx_count);
+ if (err)
+ goto out;
+ }
+
+ err = netif_set_real_num_rx_queues(dev, ch->rx_count);
+ if (err)
+ goto revert;
+
+ err = netif_set_real_num_tx_queues(dev, ch->tx_count);
+ if (err) {
+ int err2 = netif_set_real_num_rx_queues(dev, old_rx_count);
+
+ /* this error condition could happen only if rx and tx change
+ * in opposite directions (e.g. tx nr raises, rx nr decreases)
+ * and we can't do anything to fully restore the original
+ * status
+ */
+ if (err2)
+ pr_warn("Can't restore rx queues config %d -> %d %d",
+ new_rx_count, old_rx_count, err2);
+ else
+ goto revert;
+ }
+
+out:
+ if (netif_running(dev)) {
+ /* note that we need to swap the arguments WRT the enable part
+ * to identify the range we have to disable
+ */
+ veth_disable_range_safe(dev, new_rx_count, old_rx_count);
+ netif_carrier_on(dev);
+ if (peer)
+ netif_carrier_on(peer);
+ }
+ return err;
+
+revert:
+ new_rx_count = old_rx_count;
+ old_rx_count = ch->rx_count;
+ goto out;
+}
+
+static int veth_open(struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ struct net_device *peer = rtnl_dereference(priv->peer);
+ int err;
+
+ if (!peer)
+ return -ENOTCONN;
+
+ if (priv->_xdp_prog) {
+ err = veth_enable_xdp(dev);
+ if (err)
+ return err;
+ } else if (veth_gro_requested(dev)) {
+ err = veth_napi_enable(dev);
+ if (err)
+ return err;
+ }
+
+ if (peer->flags & IFF_UP) {
+ netif_carrier_on(dev);
+ netif_carrier_on(peer);
+ }
+
+ return 0;
+}
+
+static int veth_close(struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ struct net_device *peer = rtnl_dereference(priv->peer);
+
+ netif_carrier_off(dev);
+ if (peer)
+ netif_carrier_off(peer);
+
+ if (priv->_xdp_prog)
+ veth_disable_xdp(dev);
+ else if (veth_gro_requested(dev))
+ veth_napi_del(dev);
+
+ return 0;
+}
+
+static int is_valid_veth_mtu(int mtu)
+{
+ return mtu >= ETH_MIN_MTU && mtu <= ETH_MAX_MTU;
+}
+
+static int veth_alloc_queues(struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ int i;
+
+ priv->rq = kcalloc(dev->num_rx_queues, sizeof(*priv->rq), GFP_KERNEL_ACCOUNT);
+ if (!priv->rq)
+ return -ENOMEM;
+
+ for (i = 0; i < dev->num_rx_queues; i++) {
+ priv->rq[i].dev = dev;
+ u64_stats_init(&priv->rq[i].stats.syncp);
+ }
+
+ return 0;
+}
+
+static void veth_free_queues(struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+
+ kfree(priv->rq);
+}
+
+static int veth_dev_init(struct net_device *dev)
+{
+ int err;
+
+ dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
+ if (!dev->lstats)
+ return -ENOMEM;
+
+ err = veth_alloc_queues(dev);
+ if (err) {
+ free_percpu(dev->lstats);
+ return err;
+ }
+
+ return 0;
+}
+
+static void veth_dev_free(struct net_device *dev)
+{
+ veth_free_queues(dev);
+ free_percpu(dev->lstats);
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void veth_poll_controller(struct net_device *dev)
+{
+ /* veth only receives frames when its peer sends one
+ * Since it has nothing to do with disabling irqs, we are guaranteed
+ * never to have pending data when we poll for it so
+ * there is nothing to do here.
+ *
+ * We need this though so netpoll recognizes us as an interface that
+ * supports polling, which enables bridge devices in virt setups to
+ * still use netconsole
+ */
+}
+#endif /* CONFIG_NET_POLL_CONTROLLER */
+
+static int veth_get_iflink(const struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ struct net_device *peer;
+ int iflink;
+
+ rcu_read_lock();
+ peer = rcu_dereference(priv->peer);
+ iflink = peer ? peer->ifindex : 0;
+ rcu_read_unlock();
+
+ return iflink;
+}
+
+static netdev_features_t veth_fix_features(struct net_device *dev,
+ netdev_features_t features)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ struct net_device *peer;
+
+ peer = rtnl_dereference(priv->peer);
+ if (peer) {
+ struct veth_priv *peer_priv = netdev_priv(peer);
+
+ if (peer_priv->_xdp_prog)
+ features &= ~NETIF_F_GSO_SOFTWARE;
+ }
+ if (priv->_xdp_prog)
+ features |= NETIF_F_GRO;
+
+ return features;
+}
+
+static int veth_set_features(struct net_device *dev,
+ netdev_features_t features)
+{
+ netdev_features_t changed = features ^ dev->features;
+ struct veth_priv *priv = netdev_priv(dev);
+ int err;
+
+ if (!(changed & NETIF_F_GRO) || !(dev->flags & IFF_UP) || priv->_xdp_prog)
+ return 0;
+
+ if (features & NETIF_F_GRO) {
+ err = veth_napi_enable(dev);
+ if (err)
+ return err;
+ } else {
+ veth_napi_del(dev);
+ }
+ return 0;
+}
+
+static void veth_set_rx_headroom(struct net_device *dev, int new_hr)
+{
+ struct veth_priv *peer_priv, *priv = netdev_priv(dev);
+ struct net_device *peer;
+
+ if (new_hr < 0)
+ new_hr = 0;
+
+ rcu_read_lock();
+ peer = rcu_dereference(priv->peer);
+ if (unlikely(!peer))
+ goto out;
+
+ peer_priv = netdev_priv(peer);
+ priv->requested_headroom = new_hr;
+ new_hr = max(priv->requested_headroom, peer_priv->requested_headroom);
+ dev->needed_headroom = new_hr;
+ peer->needed_headroom = new_hr;
+
+out:
+ rcu_read_unlock();
+}
+
+static int veth_xdp_set(struct net_device *dev, struct bpf_prog *prog,
+ struct netlink_ext_ack *extack)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ struct bpf_prog *old_prog;
+ struct net_device *peer;
+ unsigned int max_mtu;
+ int err;
+
+ old_prog = priv->_xdp_prog;
+ priv->_xdp_prog = prog;
+ peer = rtnl_dereference(priv->peer);
+
+ if (prog) {
+ if (!peer) {
+ NL_SET_ERR_MSG_MOD(extack, "Cannot set XDP when peer is detached");
+ err = -ENOTCONN;
+ goto err;
+ }
+
+ max_mtu = SKB_WITH_OVERHEAD(PAGE_SIZE - VETH_XDP_HEADROOM) -
+ peer->hard_header_len;
+ /* Allow increasing the max_mtu if the program supports
+ * XDP fragments.
+ */
+ if (prog->aux->xdp_has_frags)
+ max_mtu += PAGE_SIZE * MAX_SKB_FRAGS;
+
+ if (peer->mtu > max_mtu) {
+ NL_SET_ERR_MSG_MOD(extack, "Peer MTU is too large to set XDP");
+ err = -ERANGE;
+ goto err;
+ }
+
+ if (dev->real_num_rx_queues < peer->real_num_tx_queues) {
+ NL_SET_ERR_MSG_MOD(extack, "XDP expects number of rx queues not less than peer tx queues");
+ err = -ENOSPC;
+ goto err;
+ }
+
+ if (dev->flags & IFF_UP) {
+ err = veth_enable_xdp(dev);
+ if (err) {
+ NL_SET_ERR_MSG_MOD(extack, "Setup for XDP failed");
+ goto err;
+ }
+ }
+
+ if (!old_prog) {
+ peer->hw_features &= ~NETIF_F_GSO_SOFTWARE;
+ peer->max_mtu = max_mtu;
+ }
+ }
+
+ if (old_prog) {
+ if (!prog) {
+ if (dev->flags & IFF_UP)
+ veth_disable_xdp(dev);
+
+ if (peer) {
+ peer->hw_features |= NETIF_F_GSO_SOFTWARE;
+ peer->max_mtu = ETH_MAX_MTU;
+ }
+ }
+ bpf_prog_put(old_prog);
+ }
+
+ if ((!!old_prog ^ !!prog) && peer)
+ netdev_update_features(peer);
+
+ return 0;
+err:
+ priv->_xdp_prog = old_prog;
+
+ return err;
+}
+
+static int veth_xdp(struct net_device *dev, struct netdev_bpf *xdp)
+{
+ switch (xdp->command) {
+ case XDP_SETUP_PROG:
+ return veth_xdp_set(dev, xdp->prog, xdp->extack);
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct net_device_ops veth_netdev_ops = {
+ .ndo_init = veth_dev_init,
+ .ndo_open = veth_open,
+ .ndo_stop = veth_close,
+ .ndo_start_xmit = veth_xmit,
+ .ndo_get_stats64 = veth_get_stats64,
+ .ndo_set_rx_mode = veth_set_multicast_list,
+ .ndo_set_mac_address = eth_mac_addr,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+ .ndo_poll_controller = veth_poll_controller,
+#endif
+ .ndo_get_iflink = veth_get_iflink,
+ .ndo_fix_features = veth_fix_features,
+ .ndo_set_features = veth_set_features,
+ .ndo_features_check = passthru_features_check,
+ .ndo_set_rx_headroom = veth_set_rx_headroom,
+ .ndo_bpf = veth_xdp,
+ .ndo_xdp_xmit = veth_ndo_xdp_xmit,
+ .ndo_get_peer_dev = veth_peer_dev,
+};
+
+#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HW_CSUM | \
+ NETIF_F_RXCSUM | NETIF_F_SCTP_CRC | NETIF_F_HIGHDMA | \
+ NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL | \
+ NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \
+ NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX )
+
+static void veth_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+
+ dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+ dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+ dev->priv_flags |= IFF_NO_QUEUE;
+ dev->priv_flags |= IFF_PHONY_HEADROOM;
+
+ dev->netdev_ops = &veth_netdev_ops;
+ dev->ethtool_ops = &veth_ethtool_ops;
+ dev->features |= NETIF_F_LLTX;
+ dev->features |= VETH_FEATURES;
+ dev->vlan_features = dev->features &
+ ~(NETIF_F_HW_VLAN_CTAG_TX |
+ NETIF_F_HW_VLAN_STAG_TX |
+ NETIF_F_HW_VLAN_CTAG_RX |
+ NETIF_F_HW_VLAN_STAG_RX);
+ dev->needs_free_netdev = true;
+ dev->priv_destructor = veth_dev_free;
+ dev->max_mtu = ETH_MAX_MTU;
+
+ dev->hw_features = VETH_FEATURES;
+ dev->hw_enc_features = VETH_FEATURES;
+ dev->mpls_features = NETIF_F_HW_CSUM | NETIF_F_GSO_SOFTWARE;
+ netif_set_tso_max_size(dev, GSO_MAX_SIZE);
+}
+
+/*
+ * netlink interface
+ */
+
+static int veth_validate(struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ if (tb[IFLA_ADDRESS]) {
+ if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
+ return -EINVAL;
+ if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
+ return -EADDRNOTAVAIL;
+ }
+ if (tb[IFLA_MTU]) {
+ if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU])))
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static struct rtnl_link_ops veth_link_ops;
+
+static void veth_disable_gro(struct net_device *dev)
+{
+ dev->features &= ~NETIF_F_GRO;
+ dev->wanted_features &= ~NETIF_F_GRO;
+ netdev_update_features(dev);
+}
+
+static int veth_init_queues(struct net_device *dev, struct nlattr *tb[])
+{
+ int err;
+
+ if (!tb[IFLA_NUM_TX_QUEUES] && dev->num_tx_queues > 1) {
+ err = netif_set_real_num_tx_queues(dev, 1);
+ if (err)
+ return err;
+ }
+ if (!tb[IFLA_NUM_RX_QUEUES] && dev->num_rx_queues > 1) {
+ err = netif_set_real_num_rx_queues(dev, 1);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+static int veth_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ int err;
+ struct net_device *peer;
+ struct veth_priv *priv;
+ char ifname[IFNAMSIZ];
+ struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
+ unsigned char name_assign_type;
+ struct ifinfomsg *ifmp;
+ struct net *net;
+
+ /*
+ * create and register peer first
+ */
+ if (data != NULL && data[VETH_INFO_PEER] != NULL) {
+ struct nlattr *nla_peer;
+
+ nla_peer = data[VETH_INFO_PEER];
+ ifmp = nla_data(nla_peer);
+ err = rtnl_nla_parse_ifinfomsg(peer_tb, nla_peer, extack);
+ if (err < 0)
+ return err;
+
+ err = veth_validate(peer_tb, NULL, extack);
+ if (err < 0)
+ return err;
+
+ tbp = peer_tb;
+ } else {
+ ifmp = NULL;
+ tbp = tb;
+ }
+
+ if (ifmp && tbp[IFLA_IFNAME]) {
+ nla_strscpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
+ name_assign_type = NET_NAME_USER;
+ } else {
+ snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
+ name_assign_type = NET_NAME_ENUM;
+ }
+
+ net = rtnl_link_get_net(src_net, tbp);
+ if (IS_ERR(net))
+ return PTR_ERR(net);
+
+ peer = rtnl_create_link(net, ifname, name_assign_type,
+ &veth_link_ops, tbp, extack);
+ if (IS_ERR(peer)) {
+ put_net(net);
+ return PTR_ERR(peer);
+ }
+
+ if (!ifmp || !tbp[IFLA_ADDRESS])
+ eth_hw_addr_random(peer);
+
+ if (ifmp && (dev->ifindex != 0))
+ peer->ifindex = ifmp->ifi_index;
+
+ netif_inherit_tso_max(peer, dev);
+
+ err = register_netdevice(peer);
+ put_net(net);
+ net = NULL;
+ if (err < 0)
+ goto err_register_peer;
+
+ /* keep GRO disabled by default to be consistent with the established
+ * veth behavior
+ */
+ veth_disable_gro(peer);
+ netif_carrier_off(peer);
+
+ err = rtnl_configure_link(peer, ifmp);
+ if (err < 0)
+ goto err_configure_peer;
+
+ /*
+ * register dev last
+ *
+ * note, that since we've registered new device the dev's name
+ * should be re-allocated
+ */
+
+ if (tb[IFLA_ADDRESS] == NULL)
+ eth_hw_addr_random(dev);
+
+ if (tb[IFLA_IFNAME])
+ nla_strscpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
+ else
+ snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
+
+ err = register_netdevice(dev);
+ if (err < 0)
+ goto err_register_dev;
+
+ netif_carrier_off(dev);
+
+ /*
+ * tie the deviced together
+ */
+
+ priv = netdev_priv(dev);
+ rcu_assign_pointer(priv->peer, peer);
+ err = veth_init_queues(dev, tb);
+ if (err)
+ goto err_queues;
+
+ priv = netdev_priv(peer);
+ rcu_assign_pointer(priv->peer, dev);
+ err = veth_init_queues(peer, tb);
+ if (err)
+ goto err_queues;
+
+ veth_disable_gro(dev);
+ return 0;
+
+err_queues:
+ unregister_netdevice(dev);
+err_register_dev:
+ /* nothing to do */
+err_configure_peer:
+ unregister_netdevice(peer);
+ return err;
+
+err_register_peer:
+ free_netdev(peer);
+ return err;
+}
+
+static void veth_dellink(struct net_device *dev, struct list_head *head)
+{
+ struct veth_priv *priv;
+ struct net_device *peer;
+
+ priv = netdev_priv(dev);
+ peer = rtnl_dereference(priv->peer);
+
+ /* Note : dellink() is called from default_device_exit_batch(),
+ * before a rcu_synchronize() point. The devices are guaranteed
+ * not being freed before one RCU grace period.
+ */
+ RCU_INIT_POINTER(priv->peer, NULL);
+ unregister_netdevice_queue(dev, head);
+
+ if (peer) {
+ priv = netdev_priv(peer);
+ RCU_INIT_POINTER(priv->peer, NULL);
+ unregister_netdevice_queue(peer, head);
+ }
+}
+
+static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = {
+ [VETH_INFO_PEER] = { .len = sizeof(struct ifinfomsg) },
+};
+
+static struct net *veth_get_link_net(const struct net_device *dev)
+{
+ struct veth_priv *priv = netdev_priv(dev);
+ struct net_device *peer = rtnl_dereference(priv->peer);
+
+ return peer ? dev_net(peer) : dev_net(dev);
+}
+
+static unsigned int veth_get_num_queues(void)
+{
+ /* enforce the same queue limit as rtnl_create_link */
+ int queues = num_possible_cpus();
+
+ if (queues > 4096)
+ queues = 4096;
+ return queues;
+}
+
+static struct rtnl_link_ops veth_link_ops = {
+ .kind = DRV_NAME,
+ .priv_size = sizeof(struct veth_priv),
+ .setup = veth_setup,
+ .validate = veth_validate,
+ .newlink = veth_newlink,
+ .dellink = veth_dellink,
+ .policy = veth_policy,
+ .maxtype = VETH_INFO_MAX,
+ .get_link_net = veth_get_link_net,
+ .get_num_tx_queues = veth_get_num_queues,
+ .get_num_rx_queues = veth_get_num_queues,
+};
+
+/*
+ * init/fini
+ */
+
+static __init int veth_init(void)
+{
+ return rtnl_link_register(&veth_link_ops);
+}
+
+static __exit void veth_exit(void)
+{
+ rtnl_link_unregister(&veth_link_ops);
+}
+
+module_init(veth_init);
+module_exit(veth_exit);
+
+MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_RTNL_LINK(DRV_NAME);