IB: address translation to map IP toIB addresses (GIDs)

Add an address translation service that maps IP addresses to
InfiniBand GID addresses using IPoIB.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

3 files changed, 377 insertions, 1 deletions

diff --git a/drivers/infiniband/Kconfig b/drivers/infiniband/Kconfig
index afc612b8577d..ba2d6505e9a4 100644
--- a/drivers/infiniband/Kconfig
+++ b/drivers/infiniband/Kconfig
@@ -29,6 +29,11 @@ config INFINIBAND_USER_ACCESS
           libibverbs, libibcm and a hardware driver library from
           <http://www.openib.org>.
 
+config INFINIBAND_ADDR_TRANS
+        bool
+        depends on INFINIBAND && INET
+        default y
+
 source "drivers/infiniband/hw/mthca/Kconfig"
 source "drivers/infiniband/hw/ipath/Kconfig"
 
diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index a56bf9c994f6..05095919d168 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -1,5 +1,7 @@
+addr_trans-$(CONFIG_INFINIBAND_ADDR_TRANS) := ib_addr.o
+
 obj-$(CONFIG_INFINIBAND) +=             ib_core.o ib_mad.o ib_sa.o \
-                                        ib_cm.o
+                                        ib_cm.o $(addr_trans-y)
 obj-$(CONFIG_INFINIBAND_USER_MAD) +=    ib_umad.o
 obj-$(CONFIG_INFINIBAND_USER_ACCESS) += ib_uverbs.o ib_ucm.o
 
@@ -12,6 +14,8 @@ ib_sa-y :=			sa_query.o
 
 ib_cm-y :=                      cm.o
 
+ib_addr-y :=                    addr.o
+
 ib_umad-y :=                    user_mad.o
 
 ib_ucm-y :=                     ucm.o
diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
new file mode 100644
index 000000000000..d294bbc42f09
--- /dev/null
+++ b/drivers/infiniband/core/addr.c
@@ -0,0 +1,367 @@
+/*
+ * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
+ * Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
+ * Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
+ * Copyright (c) 2005 Intel Corporation.  All rights reserved.
+ *
+ * This Software is licensed under one of the following licenses:
+ *
+ * 1) under the terms of the "Common Public License 1.0" a copy of which is
+ *    available from the Open Source Initiative, see
+ *    http://www.opensource.org/licenses/cpl.php.
+ *
+ * 2) under the terms of the "The BSD License" a copy of which is
+ *    available from the Open Source Initiative, see
+ *    http://www.opensource.org/licenses/bsd-license.php.
+ *
+ * 3) under the terms of the "GNU General Public License (GPL) Version 2" a
+ *    copy of which is available from the Open Source Initiative, see
+ *    http://www.opensource.org/licenses/gpl-license.php.
+ *
+ * Licensee has the right to choose one of the above licenses.
+ *
+ * Redistributions of source code must retain the above copyright
+ * notice and one of the license notices.
+ *
+ * Redistributions in binary form must reproduce both the above copyright
+ * notice, one of the license notices in the documentation
+ * and/or other materials provided with the distribution.
+ */
+
+#include <linux/mutex.h>
+#include <linux/inetdevice.h>
+#include <linux/workqueue.h>
+#include <linux/if_arp.h>
+#include <net/arp.h>
+#include <net/neighbour.h>
+#include <net/route.h>
+#include <rdma/ib_addr.h>
+
+MODULE_AUTHOR("Sean Hefty");
+MODULE_DESCRIPTION("IB Address Translation");
+MODULE_LICENSE("Dual BSD/GPL");
+
+struct addr_req {
+        struct list_head list;
+        struct sockaddr src_addr;
+        struct sockaddr dst_addr;
+        struct rdma_dev_addr *addr;
+        void *context;
+        void (*callback)(int status, struct sockaddr *src_addr,
+                         struct rdma_dev_addr *addr, void *context);
+        unsigned long timeout;
+        int status;
+};
+
+static void process_req(void *data);
+
+static DEFINE_MUTEX(lock);
+static LIST_HEAD(req_list);
+static DECLARE_WORK(work, process_req, NULL);
+static struct workqueue_struct *addr_wq;
+
+static int copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
+                     unsigned char *dst_dev_addr)
+{
+        switch (dev->type) {
+        case ARPHRD_INFINIBAND:
+                dev_addr->dev_type = IB_NODE_CA;
+                break;
+        default:
+                return -EADDRNOTAVAIL;
+        }
+
+        memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
+        memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
+        if (dst_dev_addr)
+                memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
+        return 0;
+}
+
+int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
+{
+        struct net_device *dev;
+        u32 ip = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
+        int ret;
+
+        dev = ip_dev_find(ip);
+        if (!dev)
+                return -EADDRNOTAVAIL;
+
+        ret = copy_addr(dev_addr, dev, NULL);
+        dev_put(dev);
+        return ret;
+}
+EXPORT_SYMBOL(rdma_translate_ip);
+
+static void set_timeout(unsigned long time)
+{
+        unsigned long delay;
+
+        cancel_delayed_work(&work);
+
+        delay = time - jiffies;
+        if ((long)delay <= 0)
+                delay = 1;
+
+        queue_delayed_work(addr_wq, &work, delay);
+}
+
+static void queue_req(struct addr_req *req)
+{
+        struct addr_req *temp_req;
+
+        mutex_lock(&lock);
+        list_for_each_entry_reverse(temp_req, &req_list, list) {
+                if (time_after(req->timeout, temp_req->timeout))
+                        break;
+        }
+
+        list_add(&req->list, &temp_req->list);
+
+        if (req_list.next == &req->list)
+                set_timeout(req->timeout);
+        mutex_unlock(&lock);
+}
+
+static void addr_send_arp(struct sockaddr_in *dst_in)
+{
+        struct rtable *rt;
+        struct flowi fl;
+        u32 dst_ip = dst_in->sin_addr.s_addr;
+
+        memset(&fl, 0, sizeof fl);
+        fl.nl_u.ip4_u.daddr = dst_ip;
+        if (ip_route_output_key(&rt, &fl))
+                return;
+
+        arp_send(ARPOP_REQUEST, ETH_P_ARP, rt->rt_gateway, rt->idev->dev,
+                 rt->rt_src, NULL, rt->idev->dev->dev_addr, NULL);
+        ip_rt_put(rt);
+}
+
+static int addr_resolve_remote(struct sockaddr_in *src_in,
+                               struct sockaddr_in *dst_in,
+                               struct rdma_dev_addr *addr)
+{
+        u32 src_ip = src_in->sin_addr.s_addr;
+        u32 dst_ip = dst_in->sin_addr.s_addr;
+        struct flowi fl;
+        struct rtable *rt;
+        struct neighbour *neigh;
+        int ret;
+
+        memset(&fl, 0, sizeof fl);
+        fl.nl_u.ip4_u.daddr = dst_ip;
+        fl.nl_u.ip4_u.saddr = src_ip;
+        ret = ip_route_output_key(&rt, &fl);
+        if (ret)
+                goto out;
+
+        /* If the device does ARP internally, return 'done' */
+        if (rt->idev->dev->flags & IFF_NOARP) {
+                copy_addr(addr, rt->idev->dev, NULL);
+                goto put;
+        }
+
+        neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->idev->dev);
+        if (!neigh) {
+                ret = -ENODATA;
+                goto put;
+        }
+
+        if (!(neigh->nud_state & NUD_VALID)) {
+                ret = -ENODATA;
+                goto release;
+        }
+
+        if (!src_ip) {
+                src_in->sin_family = dst_in->sin_family;
+                src_in->sin_addr.s_addr = rt->rt_src;
+        }
+
+        ret = copy_addr(addr, neigh->dev, neigh->ha);
+release:
+        neigh_release(neigh);
+put:
+        ip_rt_put(rt);
+out:
+        return ret;
+}
+
+static void process_req(void *data)
+{
+        struct addr_req *req, *temp_req;
+        struct sockaddr_in *src_in, *dst_in;
+        struct list_head done_list;
+
+        INIT_LIST_HEAD(&done_list);
+
+        mutex_lock(&lock);
+        list_for_each_entry_safe(req, temp_req, &req_list, list) {
+                if (req->status) {
+                        src_in = (struct sockaddr_in *) &req->src_addr;
+                        dst_in = (struct sockaddr_in *) &req->dst_addr;
+                        req->status = addr_resolve_remote(src_in, dst_in,
+                                                          req->addr);
+                }
+                if (req->status && time_after(jiffies, req->timeout))
+                        req->status = -ETIMEDOUT;
+                else if (req->status == -ENODATA)
+                        continue;
+
+                list_del(&req->list);
+                list_add_tail(&req->list, &done_list);
+        }
+
+        if (!list_empty(&req_list)) {
+                req = list_entry(req_list.next, struct addr_req, list);
+                set_timeout(req->timeout);
+        }
+        mutex_unlock(&lock);
+
+        list_for_each_entry_safe(req, temp_req, &done_list, list) {
+                list_del(&req->list);
+                req->callback(req->status, &req->src_addr, req->addr,
+                              req->context);
+                kfree(req);
+        }
+}
+
+static int addr_resolve_local(struct sockaddr_in *src_in,
+                              struct sockaddr_in *dst_in,
+                              struct rdma_dev_addr *addr)
+{
+        struct net_device *dev;
+        u32 src_ip = src_in->sin_addr.s_addr;
+        u32 dst_ip = dst_in->sin_addr.s_addr;
+        int ret;
+
+        dev = ip_dev_find(dst_ip);
+        if (!dev)
+                return -EADDRNOTAVAIL;
+
+        if (ZERONET(src_ip)) {
+                src_in->sin_family = dst_in->sin_family;
+                src_in->sin_addr.s_addr = dst_ip;
+                ret = copy_addr(addr, dev, dev->dev_addr);
+        } else if (LOOPBACK(src_ip)) {
+                ret = rdma_translate_ip((struct sockaddr *)dst_in, addr);
+                if (!ret)
+                        memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
+        } else {
+                ret = rdma_translate_ip((struct sockaddr *)src_in, addr);
+                if (!ret)
+                        memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
+        }
+
+        dev_put(dev);
+        return ret;
+}
+
+int rdma_resolve_ip(struct sockaddr *src_addr, struct sockaddr *dst_addr,
+                    struct rdma_dev_addr *addr, int timeout_ms,
+                    void (*callback)(int status, struct sockaddr *src_addr,
+                                     struct rdma_dev_addr *addr, void *context),
+                    void *context)
+{
+        struct sockaddr_in *src_in, *dst_in;
+        struct addr_req *req;
+        int ret = 0;
+
+        req = kmalloc(sizeof *req, GFP_KERNEL);
+        if (!req)
+                return -ENOMEM;
+        memset(req, 0, sizeof *req);
+
+        if (src_addr)
+                memcpy(&req->src_addr, src_addr, ip_addr_size(src_addr));
+        memcpy(&req->dst_addr, dst_addr, ip_addr_size(dst_addr));
+        req->addr = addr;
+        req->callback = callback;
+        req->context = context;
+
+        src_in = (struct sockaddr_in *) &req->src_addr;
+        dst_in = (struct sockaddr_in *) &req->dst_addr;
+
+        req->status = addr_resolve_local(src_in, dst_in, addr);
+        if (req->status == -EADDRNOTAVAIL)
+                req->status = addr_resolve_remote(src_in, dst_in, addr);
+
+        switch (req->status) {
+        case 0:
+                req->timeout = jiffies;
+                queue_req(req);
+                break;
+        case -ENODATA:
+                req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
+                queue_req(req);
+                addr_send_arp(dst_in);
+                break;
+        default:
+                ret = req->status;
+                kfree(req);
+                break;
+        }
+        return ret;
+}
+EXPORT_SYMBOL(rdma_resolve_ip);
+
+void rdma_addr_cancel(struct rdma_dev_addr *addr)
+{
+        struct addr_req *req, *temp_req;
+
+        mutex_lock(&lock);
+        list_for_each_entry_safe(req, temp_req, &req_list, list) {
+                if (req->addr == addr) {
+                        req->status = -ECANCELED;
+                        req->timeout = jiffies;
+                        list_del(&req->list);
+                        list_add(&req->list, &req_list);
+                        set_timeout(req->timeout);
+                        break;
+                }
+        }
+        mutex_unlock(&lock);
+}
+EXPORT_SYMBOL(rdma_addr_cancel);
+
+static int addr_arp_recv(struct sk_buff *skb, struct net_device *dev,
+                         struct packet_type *pkt, struct net_device *orig_dev)
+{
+        struct arphdr *arp_hdr;
+
+        arp_hdr = (struct arphdr *) skb->nh.raw;
+
+        if (arp_hdr->ar_op == htons(ARPOP_REQUEST) ||
+            arp_hdr->ar_op == htons(ARPOP_REPLY))
+                set_timeout(jiffies);
+
+        kfree_skb(skb);
+        return 0;
+}
+
+static struct packet_type addr_arp = {
+        .type           = __constant_htons(ETH_P_ARP),
+        .func           = addr_arp_recv,
+        .af_packet_priv = (void*) 1,
+};
+
+static int addr_init(void)
+{
+        addr_wq = create_singlethread_workqueue("ib_addr_wq");
+        if (!addr_wq)
+                return -ENOMEM;
+
+        dev_add_pack(&addr_arp);
+        return 0;
+}
+
+static void addr_cleanup(void)
+{
+        dev_remove_pack(&addr_arp);
+        destroy_workqueue(addr_wq);
+}
+
+module_init(addr_init);
+module_exit(addr_cleanup);