--- /dev/null
+/*
+ * net/tipc/ib_media.c: Infiniband bearer support for TIPC
+ *
+ * Copyright (c) 2013 Patrick McHardy <kaber@trash.net>
+ *
+ * Based on eth_media.c, which carries the following copyright notice:
+ *
+ * Copyright (c) 2001-2007, Ericsson AB
+ * Copyright (c) 2005-2008, 2011, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/if_infiniband.h>
+#include "core.h"
+#include "bearer.h"
+
+#define MAX_IB_BEARERS         MAX_BEARERS
+
+/**
+ * struct ib_bearer - Infiniband bearer data structure
+ * @bearer: ptr to associated "generic" bearer structure
+ * @dev: ptr to associated Infiniband network device
+ * @tipc_packet_type: used in binding TIPC to Infiniband driver
+ * @cleanup: work item used when disabling bearer
+ */
+
+struct ib_bearer {
+       struct tipc_bearer *bearer;
+       struct net_device *dev;
+       struct packet_type tipc_packet_type;
+       struct work_struct setup;
+       struct work_struct cleanup;
+};
+
+static struct tipc_media ib_media_info;
+static struct ib_bearer ib_bearers[MAX_IB_BEARERS];
+static int ib_started;
+
+/**
+ * ib_media_addr_set - initialize Infiniband media address structure
+ *
+ * Media-dependent "value" field stores MAC address in first 6 bytes
+ * and zeroes out the remaining bytes.
+ */
+static void ib_media_addr_set(const struct tipc_bearer *tb_ptr,
+                             struct tipc_media_addr *a, char *mac)
+{
+       BUILD_BUG_ON(sizeof(a->value) < INFINIBAND_ALEN);
+       memcpy(a->value, mac, INFINIBAND_ALEN);
+       a->media_id = TIPC_MEDIA_TYPE_IB;
+       a->broadcast = !memcmp(mac, tb_ptr->bcast_addr.value, INFINIBAND_ALEN);
+}
+
+/**
+ * send_msg - send a TIPC message out over an InfiniBand interface
+ */
+static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
+                   struct tipc_media_addr *dest)
+{
+       struct sk_buff *clone;
+       struct net_device *dev;
+       int delta;
+
+       clone = skb_clone(buf, GFP_ATOMIC);
+       if (!clone)
+               return 0;
+
+       dev = ((struct ib_bearer *)(tb_ptr->usr_handle))->dev;
+       delta = dev->hard_header_len - skb_headroom(buf);
+
+       if ((delta > 0) &&
+           pskb_expand_head(clone, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) {
+               kfree_skb(clone);
+               return 0;
+       }
+
+       skb_reset_network_header(clone);
+       clone->dev = dev;
+       clone->protocol = htons(ETH_P_TIPC);
+       dev_hard_header(clone, dev, ETH_P_TIPC, dest->value,
+                       dev->dev_addr, clone->len);
+       dev_queue_xmit(clone);
+       return 0;
+}
+
+/**
+ * recv_msg - handle incoming TIPC message from an InfiniBand interface
+ *
+ * Accept only packets explicitly sent to this node, or broadcast packets;
+ * ignores packets sent using InfiniBand multicast, and traffic sent to other
+ * nodes (which can happen if interface is running in promiscuous mode).
+ */
+static int recv_msg(struct sk_buff *buf, struct net_device *dev,
+                   struct packet_type *pt, struct net_device *orig_dev)
+{
+       struct ib_bearer *ib_ptr = (struct ib_bearer *)pt->af_packet_priv;
+
+       if (!net_eq(dev_net(dev), &init_net)) {
+               kfree_skb(buf);
+               return 0;
+       }
+
+       if (likely(ib_ptr->bearer)) {
+               if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
+                       buf->next = NULL;
+                       tipc_recv_msg(buf, ib_ptr->bearer);
+                       return 0;
+               }
+       }
+       kfree_skb(buf);
+       return 0;
+}
+
+/**
+ * setup_bearer - setup association between InfiniBand bearer and interface
+ */
+static void setup_bearer(struct work_struct *work)
+{
+       struct ib_bearer *ib_ptr =
+               container_of(work, struct ib_bearer, setup);
+
+       dev_add_pack(&ib_ptr->tipc_packet_type);
+}
+
+/**
+ * enable_bearer - attach TIPC bearer to an InfiniBand interface
+ */
+static int enable_bearer(struct tipc_bearer *tb_ptr)
+{
+       struct net_device *dev = NULL;
+       struct net_device *pdev = NULL;
+       struct ib_bearer *ib_ptr = &ib_bearers[0];
+       struct ib_bearer *stop = &ib_bearers[MAX_IB_BEARERS];
+       char *driver_name = strchr((const char *)tb_ptr->name, ':') + 1;
+       int pending_dev = 0;
+
+       /* Find unused InfiniBand bearer structure */
+       while (ib_ptr->dev) {
+               if (!ib_ptr->bearer)
+                       pending_dev++;
+               if (++ib_ptr == stop)
+                       return pending_dev ? -EAGAIN : -EDQUOT;
+       }
+
+       /* Find device with specified name */
+       read_lock(&dev_base_lock);
+       for_each_netdev(&init_net, pdev) {
+               if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) {
+                       dev = pdev;
+                       dev_hold(dev);
+                       break;
+               }
+       }
+       read_unlock(&dev_base_lock);
+       if (!dev)
+               return -ENODEV;
+
+       /* Create InfiniBand bearer for device */
+       ib_ptr->dev = dev;
+       ib_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
+       ib_ptr->tipc_packet_type.dev = dev;
+       ib_ptr->tipc_packet_type.func = recv_msg;
+       ib_ptr->tipc_packet_type.af_packet_priv = ib_ptr;
+       INIT_LIST_HEAD(&(ib_ptr->tipc_packet_type.list));
+       INIT_WORK(&ib_ptr->setup, setup_bearer);
+       schedule_work(&ib_ptr->setup);
+
+       /* Associate TIPC bearer with InfiniBand bearer */
+       ib_ptr->bearer = tb_ptr;
+       tb_ptr->usr_handle = (void *)ib_ptr;
+       memset(tb_ptr->bcast_addr.value, 0, sizeof(tb_ptr->bcast_addr.value));
+       memcpy(tb_ptr->bcast_addr.value, dev->broadcast, INFINIBAND_ALEN);
+       tb_ptr->bcast_addr.media_id = TIPC_MEDIA_TYPE_IB;
+       tb_ptr->bcast_addr.broadcast = 1;
+       tb_ptr->mtu = dev->mtu;
+       tb_ptr->blocked = 0;
+       ib_media_addr_set(tb_ptr, &tb_ptr->addr, (char *)dev->dev_addr);
+       return 0;
+}
+
+/**
+ * cleanup_bearer - break association between InfiniBand bearer and interface
+ *
+ * This routine must be invoked from a work queue because it can sleep.
+ */
+static void cleanup_bearer(struct work_struct *work)
+{
+       struct ib_bearer *ib_ptr =
+               container_of(work, struct ib_bearer, cleanup);
+
+       dev_remove_pack(&ib_ptr->tipc_packet_type);
+       dev_put(ib_ptr->dev);
+       ib_ptr->dev = NULL;
+}
+
+/**
+ * disable_bearer - detach TIPC bearer from an InfiniBand interface
+ *
+ * Mark InfiniBand bearer as inactive so that incoming buffers are thrown away,
+ * then get worker thread to complete bearer cleanup.  (Can't do cleanup
+ * here because cleanup code needs to sleep and caller holds spinlocks.)
+ */
+static void disable_bearer(struct tipc_bearer *tb_ptr)
+{
+       struct ib_bearer *ib_ptr = (struct ib_bearer *)tb_ptr->usr_handle;
+
+       ib_ptr->bearer = NULL;
+       INIT_WORK(&ib_ptr->cleanup, cleanup_bearer);
+       schedule_work(&ib_ptr->cleanup);
+}
+
+/**
+ * recv_notification - handle device updates from OS
+ *
+ * Change the state of the InfiniBand bearer (if any) associated with the
+ * specified device.
+ */
+static int recv_notification(struct notifier_block *nb, unsigned long evt,
+                            void *dv)
+{
+       struct net_device *dev = (struct net_device *)dv;
+       struct ib_bearer *ib_ptr = &ib_bearers[0];
+       struct ib_bearer *stop = &ib_bearers[MAX_IB_BEARERS];
+
+       if (!net_eq(dev_net(dev), &init_net))
+               return NOTIFY_DONE;
+
+       while ((ib_ptr->dev != dev)) {
+               if (++ib_ptr == stop)
+                       return NOTIFY_DONE;     /* couldn't find device */
+       }
+       if (!ib_ptr->bearer)
+               return NOTIFY_DONE;             /* bearer had been disabled */
+
+       ib_ptr->bearer->mtu = dev->mtu;
+
+       switch (evt) {
+       case NETDEV_CHANGE:
+               if (netif_carrier_ok(dev))
+                       tipc_continue(ib_ptr->bearer);
+               else
+                       tipc_block_bearer(ib_ptr->bearer->name);
+               break;
+       case NETDEV_UP:
+               tipc_continue(ib_ptr->bearer);
+               break;
+       case NETDEV_DOWN:
+               tipc_block_bearer(ib_ptr->bearer->name);
+               break;
+       case NETDEV_CHANGEMTU:
+       case NETDEV_CHANGEADDR:
+               tipc_block_bearer(ib_ptr->bearer->name);
+               tipc_continue(ib_ptr->bearer);
+               break;
+       case NETDEV_UNREGISTER:
+       case NETDEV_CHANGENAME:
+               tipc_disable_bearer(ib_ptr->bearer->name);
+               break;
+       }
+       return NOTIFY_OK;
+}
+
+static struct notifier_block notifier = {
+       .notifier_call  = recv_notification,
+       .priority       = 0,
+};
+
+/**
+ * ib_addr2str - convert InfiniBand address to string
+ */
+static int ib_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
+{
+       if (str_size < 60)      /* 60 = 19 * strlen("xx:") + strlen("xx\0") */
+               return 1;
+
+       sprintf(str_buf, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:"
+                        "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
+               a->value[0], a->value[1], a->value[2], a->value[3],
+               a->value[4], a->value[5], a->value[6], a->value[7],
+               a->value[8], a->value[9], a->value[10], a->value[11],
+               a->value[12], a->value[13], a->value[14], a->value[15],
+               a->value[16], a->value[17], a->value[18], a->value[19]);
+
+       return 0;
+}
+
+/**
+ * ib_addr2msg - convert InfiniBand address format to message header format
+ */
+static int ib_addr2msg(struct tipc_media_addr *a, char *msg_area)
+{
+       memset(msg_area, 0, TIPC_MEDIA_ADDR_SIZE);
+       msg_area[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_IB;
+       memcpy(msg_area, a->value, INFINIBAND_ALEN);
+       return 0;
+}
+
+/**
+ * ib_msg2addr - convert message header address format to InfiniBand format
+ */
+static int ib_msg2addr(const struct tipc_bearer *tb_ptr,
+                      struct tipc_media_addr *a, char *msg_area)
+{
+       ib_media_addr_set(tb_ptr, a, msg_area);
+       return 0;
+}
+
+/*
+ * InfiniBand media registration info
+ */
+static struct tipc_media ib_media_info = {
+       .send_msg       = send_msg,
+       .enable_bearer  = enable_bearer,
+       .disable_bearer = disable_bearer,
+       .addr2str       = ib_addr2str,
+       .addr2msg       = ib_addr2msg,
+       .msg2addr       = ib_msg2addr,
+       .priority       = TIPC_DEF_LINK_PRI,
+       .tolerance      = TIPC_DEF_LINK_TOL,
+       .window         = TIPC_DEF_LINK_WIN,
+       .type_id        = TIPC_MEDIA_TYPE_IB,
+       .name           = "ib"
+};
+
+/**
+ * tipc_ib_media_start - activate InfiniBand bearer support
+ *
+ * Register InfiniBand media type with TIPC bearer code.  Also register
+ * with OS for notifications about device state changes.
+ */
+int tipc_ib_media_start(void)
+{
+       int res;
+
+       if (ib_started)
+               return -EINVAL;
+
+       res = tipc_register_media(&ib_media_info);
+       if (res)
+               return res;
+
+       res = register_netdevice_notifier(¬ifier);
+       if (!res)
+               ib_started = 1;
+       return res;
+}
+
+/**
+ * tipc_ib_media_stop - deactivate InfiniBand bearer support
+ */
+void tipc_ib_media_stop(void)
+{
+       if (!ib_started)
+               return;
+
+       flush_scheduled_work();
+       unregister_netdevice_notifier(¬ifier);
+       ib_started = 0;
+}