RDMA/cma: Add support for AF_IB to rdma_resolve_addr()

Allow the user to specify the remote address using AF_IB format.  When
AF_IB is used, the remote address simply needs to be recorded, and no
resolution using ARP is done.  The local address may still need to be
matched with a local IB device.

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

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 9f6e719cf6207d1842a4db6567ec228dd87bb018..7a159af086307953430d7a587c01fcfce8847180 100644 (file)
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -438,6 +438,61 @@ out:
        return ret;
 }
 
+/*
+ * Select the source IB device and address to reach the destination IB address.
+ */
+static int cma_resolve_ib_dev(struct rdma_id_private *id_priv)
+{
+       struct cma_device *cma_dev, *cur_dev;
+       struct sockaddr_ib *addr;
+       union ib_gid gid, sgid, *dgid;
+       u16 pkey, index;
+       u8 port, p;
+       int i;
+
+       cma_dev = NULL;
+       addr = (struct sockaddr_ib *) cma_dst_addr(id_priv);
+       dgid = (union ib_gid *) &addr->sib_addr;
+       pkey = ntohs(addr->sib_pkey);
+
+       list_for_each_entry(cur_dev, &dev_list, list) {
+               if (rdma_node_get_transport(cur_dev->device->node_type) != RDMA_TRANSPORT_IB)
+                       continue;
+
+               for (p = 1; p <= cur_dev->device->phys_port_cnt; ++p) {
+                       if (ib_find_cached_pkey(cur_dev->device, p, pkey, &index))
+                               continue;
+
+                       for (i = 0; !ib_get_cached_gid(cur_dev->device, p, i, &gid); i++) {
+                               if (!memcmp(&gid, dgid, sizeof(gid))) {
+                                       cma_dev = cur_dev;
+                                       sgid = gid;
+                                       port = p;
+                                       goto found;
+                               }
+
+                               if (!cma_dev && (gid.global.subnet_prefix ==
+                                                dgid->global.subnet_prefix)) {
+                                       cma_dev = cur_dev;
+                                       sgid = gid;
+                                       port = p;
+                               }
+                       }
+               }
+       }
+
+       if (!cma_dev)
+               return -ENODEV;
+
+found:
+       cma_attach_to_dev(id_priv, cma_dev);
+       id_priv->id.port_num = port;
+       addr = (struct sockaddr_ib *) cma_src_addr(id_priv);
+       memcpy(&addr->sib_addr, &sgid, sizeof sgid);
+       cma_translate_ib(addr, &id_priv->id.route.addr.dev_addr);
+       return 0;
+}
+
 static void cma_deref_id(struct rdma_id_private *id_priv)
 {
        if (atomic_dec_and_test(&id_priv->refcount))
@@ -2101,14 +2156,48 @@ err:
        return ret;
 }
 
+static int cma_resolve_ib_addr(struct rdma_id_private *id_priv)
+{
+       struct cma_work *work;
+       int ret;
+
+       work = kzalloc(sizeof *work, GFP_KERNEL);
+       if (!work)
+               return -ENOMEM;
+
+       if (!id_priv->cma_dev) {
+               ret = cma_resolve_ib_dev(id_priv);
+               if (ret)
+                       goto err;
+       }
+
+       rdma_addr_set_dgid(&id_priv->id.route.addr.dev_addr, (union ib_gid *)
+               &(((struct sockaddr_ib *) &id_priv->id.route.addr.dst_addr)->sib_addr));
+
+       work->id = id_priv;
+       INIT_WORK(&work->work, cma_work_handler);
+       work->old_state = RDMA_CM_ADDR_QUERY;
+       work->new_state = RDMA_CM_ADDR_RESOLVED;
+       work->event.event = RDMA_CM_EVENT_ADDR_RESOLVED;
+       queue_work(cma_wq, &work->work);
+       return 0;
+err:
+       kfree(work);
+       return ret;
+}
+
 static int cma_bind_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
                         struct sockaddr *dst_addr)
 {
        if (!src_addr || !src_addr->sa_family) {
                src_addr = (struct sockaddr *) &id->route.addr.src_addr;
-               if ((src_addr->sa_family = dst_addr->sa_family) == AF_INET6) {
+               src_addr->sa_family = dst_addr->sa_family;
+               if (dst_addr->sa_family == AF_INET6) {
                        ((struct sockaddr_in6 *) src_addr)->sin6_scope_id =
                                ((struct sockaddr_in6 *) dst_addr)->sin6_scope_id;
+               } else if (dst_addr->sa_family == AF_IB) {
+                       ((struct sockaddr_ib *) src_addr)->sib_pkey =
+                               ((struct sockaddr_ib *) dst_addr)->sib_pkey;
                }
        }
        return rdma_bind_addr(id, src_addr);
@@ -2135,12 +2224,17 @@ int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
 
        atomic_inc(&id_priv->refcount);
        memcpy(cma_dst_addr(id_priv), dst_addr, rdma_addr_size(dst_addr));
-       if (cma_any_addr(dst_addr))
+       if (cma_any_addr(dst_addr)) {
                ret = cma_resolve_loopback(id_priv);
-       else
-               ret = rdma_resolve_ip(&addr_client, cma_src_addr(id_priv),
-                                     dst_addr, &id->route.addr.dev_addr,
-                                     timeout_ms, addr_handler, id_priv);
+       } else {
+               if (dst_addr->sa_family == AF_IB) {
+                       ret = cma_resolve_ib_addr(id_priv);
+               } else {
+                       ret = rdma_resolve_ip(&addr_client, cma_src_addr(id_priv),
+                                             dst_addr, &id->route.addr.dev_addr,
+                                             timeout_ms, addr_handler, id_priv);
+               }
+       }
        if (ret)
                goto err;