Add ioctls and storage required for the virtio-net hash feature to TAP.
Signed-off-by: Akihiko Odaki akihiko.odaki@daynix.com --- drivers/net/ipvlan/ipvtap.c | 2 +- drivers/net/macvtap.c | 2 +- drivers/net/tap.c | 70 +++++++++++++++++++++++++++++++++++++++++---- include/linux/if_tap.h | 4 ++- 4 files changed, 69 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ipvlan/ipvtap.c b/drivers/net/ipvlan/ipvtap.c index 1afc4c47be73..305438abf7ae 100644 --- a/drivers/net/ipvlan/ipvtap.c +++ b/drivers/net/ipvlan/ipvtap.c @@ -114,7 +114,7 @@ static void ipvtap_dellink(struct net_device *dev, struct ipvtap_dev *vlan = netdev_priv(dev);
netdev_rx_handler_unregister(dev); - tap_del_queues(&vlan->tap); + tap_del(&vlan->tap); ipvlan_link_delete(dev, head); }
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 29a5929d48e5..e72144d05ef4 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -122,7 +122,7 @@ static void macvtap_dellink(struct net_device *dev, struct macvtap_dev *vlantap = netdev_priv(dev);
netdev_rx_handler_unregister(dev); - tap_del_queues(&vlantap->tap); + tap_del(&vlantap->tap); macvlan_dellink(dev, head); }
diff --git a/drivers/net/tap.c b/drivers/net/tap.c index 25c60ff2d3f2..2213a2aa83a8 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -49,6 +49,10 @@ struct major_info { struct list_head next; };
+struct tap_skb_cb { + struct virtio_net_hash hash; +}; + #define GOODCOPY_LEN 128
static const struct proto_ops tap_socket_ops; @@ -179,9 +183,20 @@ static void tap_put_queue(struct tap_queue *q) sock_put(&q->sk); }
+static struct tap_skb_cb *tap_skb_cb(const struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct tap_skb_cb)); + return (struct tap_skb_cb *)skb->cb; +} + +static struct virtio_net_hash *tap_add_hash(struct sk_buff *skb) +{ + return &tap_skb_cb(skb)->hash; +} + static const struct virtio_net_hash *tap_find_hash(const struct sk_buff *skb) { - return NULL; + return &tap_skb_cb(skb)->hash; }
/* @@ -194,6 +209,7 @@ static const struct virtio_net_hash *tap_find_hash(const struct sk_buff *skb) static struct tap_queue *tap_get_queue(struct tap_dev *tap, struct sk_buff *skb) { + struct flow_keys_basic keys_basic; struct tap_queue *queue = NULL; /* Access to taps array is protected by rcu, but access to numvtaps * isn't. Below we use it to lookup a queue, but treat it as a hint @@ -201,17 +217,47 @@ static struct tap_queue *tap_get_queue(struct tap_dev *tap, * racing against queue removal. */ int numvtaps = READ_ONCE(tap->numvtaps); + struct tun_vnet_hash_container *vnet_hash = rcu_dereference(tap->vnet_hash); __u32 rxq;
+ *tap_skb_cb(skb) = (struct tap_skb_cb) { + .hash = { .report = VIRTIO_NET_HASH_REPORT_NONE } + }; + if (!numvtaps) goto out;
if (numvtaps == 1) goto single;
+ if (vnet_hash) { + if ((vnet_hash->common.flags & TUN_VNET_HASH_RSS)) { + rxq = tun_vnet_rss_select_queue(numvtaps, vnet_hash, skb, tap_add_hash); + queue = rcu_dereference(tap->taps[rxq]); + goto out; + } + + if (!skb->l4_hash && !skb->sw_hash) { + struct flow_keys keys; + + skb_flow_dissect_flow_keys(skb, &keys, FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL); + rxq = flow_hash_from_keys(&keys); + keys_basic = (struct flow_keys_basic) { + .control = keys.control, + .basic = keys.basic + }; + } else { + skb_flow_dissect_flow_keys_basic(NULL, skb, &keys_basic, NULL, 0, 0, 0, + FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL); + rxq = skb->hash; + } + } else { + rxq = skb_get_hash(skb); + } + /* Check if we can use flow to select a queue */ - rxq = skb_get_hash(skb); if (rxq) { + tun_vnet_hash_report(vnet_hash, skb, &keys_basic, rxq, tap_add_hash); queue = rcu_dereference(tap->taps[rxq % numvtaps]); goto out; } @@ -234,10 +280,10 @@ static struct tap_queue *tap_get_queue(struct tap_dev *tap,
/* * The net_device is going away, give up the reference - * that it holds on all queues and safely set the pointer - * from the queues to NULL. + * that it holds on all queues, safely set the pointer + * from the queues to NULL, and free vnet_hash. */ -void tap_del_queues(struct tap_dev *tap) +void tap_del(struct tap_dev *tap) { struct tap_queue *q, *tmp;
@@ -254,8 +300,10 @@ void tap_del_queues(struct tap_dev *tap) BUG_ON(tap->numqueues); /* guarantee that any future tap_set_queue will fail */ tap->numvtaps = MAX_TAP_QUEUES; + + kfree_rcu_mightsleep(rtnl_dereference(tap->vnet_hash)); } -EXPORT_SYMBOL_GPL(tap_del_queues); +EXPORT_SYMBOL_GPL(tap_del);
rx_handler_result_t tap_handle_frame(struct sk_buff **pskb) { @@ -998,6 +1046,16 @@ static long tap_ioctl(struct file *file, unsigned int cmd, rtnl_unlock(); return ret;
+ case TUNGETVNETHASHCAP: + return tun_vnet_ioctl_gethashcap(argp); + + case TUNSETVNETHASH: + rtnl_lock(); + tap = rtnl_dereference(q->tap); + ret = tap ? tun_vnet_ioctl_sethash(&tap->vnet_hash, argp) : -EBADFD; + rtnl_unlock(); + return ret; + case SIOCGIFHWADDR: rtnl_lock(); tap = tap_get_tap_dev(q); diff --git a/include/linux/if_tap.h b/include/linux/if_tap.h index 553552fa635c..9e8e02822d9c 100644 --- a/include/linux/if_tap.h +++ b/include/linux/if_tap.h @@ -31,6 +31,7 @@ static inline struct ptr_ring *tap_get_ptr_ring(struct file *f) #define MAX_TAP_QUEUES 256
struct tap_queue; +struct tun_vnet_hash_container;
struct tap_dev { struct net_device *dev; @@ -43,6 +44,7 @@ struct tap_dev { int numqueues; netdev_features_t tap_features; int minor; + struct tun_vnet_hash_container __rcu *vnet_hash;
void (*update_features)(struct tap_dev *tap, netdev_features_t features); void (*count_tx_dropped)(struct tap_dev *tap); @@ -74,7 +76,7 @@ struct tap_queue { };
rx_handler_result_t tap_handle_frame(struct sk_buff **pskb); -void tap_del_queues(struct tap_dev *tap); +void tap_del(struct tap_dev *tap); int tap_get_minor(dev_t major, struct tap_dev *tap); void tap_free_minor(dev_t major, struct tap_dev *tap); int tap_queue_resize(struct tap_dev *tap);