IB/opa-vnic: Virtual Network Interface Controller (VNIC) netdev

OPA VNIC netdev function supports Ethernet functionality over Omni-Path
fabric by encapsulating Ethernet packets inside Omni-Path packet header.
It allocates a rdma netdev device and interfaces with the network stack to
provide standard Ethernet network interfaces. It overrides HFI1 device's
netdev operations where it is required.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: Sadanand Warrier <sadanand.warrier@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Andrzej Kacprowski <andrzej.kacprowski@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 227 insertions, 0 deletions

diff --git a/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c b/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c
new file mode 100644
index 000000000000..1e237b68e21b
--- /dev/null
+++ b/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c
@@ -0,0 +1,227 @@
+/*
+ * Copyright(c) 2017 Intel Corporation.
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * BSD LICENSE
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  - Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  - Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  - Neither the name of Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+/*
+ * This file contains OPA Virtual Network Interface Controller (VNIC) driver
+ * netdev functionality.
+ */
+
+#include <linux/module.h>
+#include <linux/if_vlan.h>
+
+#include "opa_vnic_internal.h"
+
+#define OPA_TX_TIMEOUT_MS 1000
+
+#define OPA_VNIC_SKB_HEADROOM  \
+			ALIGN((OPA_VNIC_HDR_LEN + OPA_VNIC_SKB_MDATA_LEN), 8)
+
+/* opa_netdev_start_xmit - transmit function */
+static netdev_tx_t opa_netdev_start_xmit(struct sk_buff *skb,
+					 struct net_device *netdev)
+{
+	struct opa_vnic_adapter *adapter = opa_vnic_priv(netdev);
+
+	v_dbg("xmit: queue %d skb len %d\n", skb->queue_mapping, skb->len);
+	/* pad to ensure mininum ethernet packet length */
+	if (unlikely(skb->len < ETH_ZLEN)) {
+		if (skb_padto(skb, ETH_ZLEN))
+			return NETDEV_TX_OK;
+
+		skb_put(skb, ETH_ZLEN - skb->len);
+	}
+
+	opa_vnic_encap_skb(adapter, skb);
+	return adapter->rn_ops->ndo_start_xmit(skb, netdev);
+}
+
+static u16 opa_vnic_select_queue(struct net_device *netdev, struct sk_buff *skb,
+				 void *accel_priv,
+				 select_queue_fallback_t fallback)
+{
+	struct opa_vnic_adapter *adapter = opa_vnic_priv(netdev);
+	struct opa_vnic_skb_mdata *mdata;
+	int rc;
+
+	/* pass entropy and vl as metadata in skb */
+	mdata = (struct opa_vnic_skb_mdata *)skb_push(skb, sizeof(*mdata));
+	mdata->entropy =  opa_vnic_calc_entropy(adapter, skb);
+	mdata->vl = opa_vnic_get_vl(adapter, skb);
+	rc = adapter->rn_ops->ndo_select_queue(netdev, skb,
+					       accel_priv, fallback);
+	skb_pull(skb, sizeof(*mdata));
+	return rc;
+}
+
+/* opa_vnic_set_mac_addr - change mac address */
+static int opa_vnic_set_mac_addr(struct net_device *netdev, void *addr)
+{
+	struct opa_vnic_adapter *adapter = opa_vnic_priv(netdev);
+	struct sockaddr *sa = addr;
+	int rc;
+
+	if (!memcmp(netdev->dev_addr, sa->sa_data, ETH_ALEN))
+		return 0;
+
+	mutex_lock(&adapter->lock);
+	rc = eth_mac_addr(netdev, addr);
+	mutex_unlock(&adapter->lock);
+
+	return rc;
+}
+
+/* opa_netdev_open - activate network interface */
+static int opa_netdev_open(struct net_device *netdev)
+{
+	struct opa_vnic_adapter *adapter = opa_vnic_priv(netdev);
+	int rc;
+
+	rc = adapter->rn_ops->ndo_open(adapter->netdev);
+	if (rc) {
+		v_dbg("open failed %d\n", rc);
+		return rc;
+	}
+
+	return 0;
+}
+
+/* opa_netdev_close - disable network interface */
+static int opa_netdev_close(struct net_device *netdev)
+{
+	struct opa_vnic_adapter *adapter = opa_vnic_priv(netdev);
+	int rc;
+
+	rc = adapter->rn_ops->ndo_stop(adapter->netdev);
+	if (rc) {
+		v_dbg("close failed %d\n", rc);
+		return rc;
+	}
+
+	return 0;
+}
+
+/* netdev ops */
+static const struct net_device_ops opa_netdev_ops = {
+	.ndo_open = opa_netdev_open,
+	.ndo_stop = opa_netdev_close,
+	.ndo_start_xmit = opa_netdev_start_xmit,
+	.ndo_select_queue = opa_vnic_select_queue,
+	.ndo_set_mac_address = opa_vnic_set_mac_addr,
+};
+
+/* opa_vnic_add_netdev - create vnic netdev interface */
+struct opa_vnic_adapter *opa_vnic_add_netdev(struct ib_device *ibdev,
+					     u8 port_num, u8 vport_num)
+{
+	struct opa_vnic_adapter *adapter;
+	struct net_device *netdev;
+	struct rdma_netdev *rn;
+	int rc;
+
+	netdev = ibdev->alloc_rdma_netdev(ibdev, port_num,
+					  RDMA_NETDEV_OPA_VNIC,
+					  "veth%d", NET_NAME_UNKNOWN,
+					  ether_setup);
+	if (!netdev)
+		return ERR_PTR(-ENOMEM);
+	else if (IS_ERR(netdev))
+		return ERR_CAST(netdev);
+
+	adapter = kzalloc(sizeof(*adapter), GFP_KERNEL);
+	if (!adapter) {
+		rc = -ENOMEM;
+		goto adapter_err;
+	}
+
+	rn = netdev_priv(netdev);
+	rn->clnt_priv = adapter;
+	rn->hca = ibdev;
+	rn->port_num = port_num;
+	adapter->netdev = netdev;
+	adapter->ibdev = ibdev;
+	adapter->port_num = port_num;
+	adapter->vport_num = vport_num;
+	adapter->rn_ops = netdev->netdev_ops;
+
+	netdev->netdev_ops = &opa_netdev_ops;
+	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+	netdev->hard_header_len += OPA_VNIC_SKB_HEADROOM;
+	mutex_init(&adapter->lock);
+
+	SET_NETDEV_DEV(netdev, ibdev->dev.parent);
+
+	opa_vnic_set_ethtool_ops(netdev);
+	rc = register_netdev(netdev);
+	if (rc)
+		goto netdev_err;
+
+	netif_carrier_off(netdev);
+	netif_dormant_on(netdev);
+	v_info("initialized\n");
+
+	return adapter;
+netdev_err:
+	mutex_destroy(&adapter->lock);
+	kfree(adapter);
+adapter_err:
+	ibdev->free_rdma_netdev(netdev);
+
+	return ERR_PTR(rc);
+}
+
+/* opa_vnic_rem_netdev - remove vnic netdev interface */
+void opa_vnic_rem_netdev(struct opa_vnic_adapter *adapter)
+{
+	struct net_device *netdev = adapter->netdev;
+	struct ib_device *ibdev = adapter->ibdev;
+
+	v_info("removing\n");
+	unregister_netdev(netdev);
+	mutex_destroy(&adapter->lock);
+	kfree(adapter);
+	ibdev->free_rdma_netdev(netdev);
+}