2 files changed, 130 insertions, 67 deletions

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index eff5e46f005c..99dde874fbbd 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -148,6 +148,7 @@ struct rdma_id_private {
         u32                     qp_num;
         u8                      srq;
         u8                      tos;
+        u8                      reuseaddr;
 };
 
 struct cma_multicast {
@@ -1579,50 +1580,6 @@ static void cma_listen_on_all(struct rdma_id_private *id_priv)
         mutex_unlock(&lock);
 }
 
-int rdma_listen(struct rdma_cm_id *id, int backlog)
-{
-        struct rdma_id_private *id_priv;
-        int ret;
-
-        id_priv = container_of(id, struct rdma_id_private, id);
-        if (id_priv->state == CMA_IDLE) {
-                ((struct sockaddr *) &id->route.addr.src_addr)->sa_family = AF_INET;
-                ret = rdma_bind_addr(id, (struct sockaddr *) &id->route.addr.src_addr);
-                if (ret)
-                        return ret;
-        }
-
-        if (!cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_LISTEN))
-                return -EINVAL;
-
-        id_priv->backlog = backlog;
-        if (id->device) {
-                switch (rdma_node_get_transport(id->device->node_type)) {
-                case RDMA_TRANSPORT_IB:
-                        ret = cma_ib_listen(id_priv);
-                        if (ret)
-                                goto err;
-                        break;
-                case RDMA_TRANSPORT_IWARP:
-                        ret = cma_iw_listen(id_priv, backlog);
-                        if (ret)
-                                goto err;
-                        break;
-                default:
-                        ret = -ENOSYS;
-                        goto err;
-                }
-        } else
-                cma_listen_on_all(id_priv);
-
-        return 0;
-err:
-        id_priv->backlog = 0;
-        cma_comp_exch(id_priv, CMA_LISTEN, CMA_ADDR_BOUND);
-        return ret;
-}
-EXPORT_SYMBOL(rdma_listen);
-
 void rdma_set_service_type(struct rdma_cm_id *id, int tos)
 {
         struct rdma_id_private *id_priv;
@@ -2105,6 +2062,25 @@ err:
 }
 EXPORT_SYMBOL(rdma_resolve_addr);
 
+int rdma_set_reuseaddr(struct rdma_cm_id *id, int reuse)
+{
+        struct rdma_id_private *id_priv;
+        unsigned long flags;
+        int ret;
+
+        id_priv = container_of(id, struct rdma_id_private, id);
+        spin_lock_irqsave(&id_priv->lock, flags);
+        if (id_priv->state == CMA_IDLE) {
+                id_priv->reuseaddr = reuse;
+                ret = 0;
+        } else {
+                ret = -EINVAL;
+        }
+        spin_unlock_irqrestore(&id_priv->lock, flags);
+        return ret;
+}
+EXPORT_SYMBOL(rdma_set_reuseaddr);
+
 static void cma_bind_port(struct rdma_bind_list *bind_list,
                           struct rdma_id_private *id_priv)
 {
@@ -2180,43 +2156,73 @@ retry:
         return -EADDRNOTAVAIL;
 }
 
-static int cma_use_port(struct idr *ps, struct rdma_id_private *id_priv)
+/*
+ * Check that the requested port is available.  This is called when trying to
+ * bind to a specific port, or when trying to listen on a bound port.  In
+ * the latter case, the provided id_priv may already be on the bind_list, but
+ * we still need to check that it's okay to start listening.
+ */
+static int cma_check_port(struct rdma_bind_list *bind_list,
+                          struct rdma_id_private *id_priv, uint8_t reuseaddr)
 {
         struct rdma_id_private *cur_id;
         struct sockaddr *addr, *cur_addr;
-        struct rdma_bind_list *bind_list;
         struct hlist_node *node;
-        unsigned short snum;
 
         addr = (struct sockaddr *) &id_priv->id.route.addr.src_addr;
-        snum = ntohs(cma_port(addr));
-        if (snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
-                return -EACCES;
-
-        bind_list = idr_find(ps, snum);
-        if (!bind_list)
-                return cma_alloc_port(ps, id_priv, snum);
-
-        /*
-         * We don't support binding to any address if anyone is bound to
-         * a specific address on the same port.
-         */
-        if (cma_any_addr(addr))
+        if (cma_any_addr(addr) && !reuseaddr)
                 return -EADDRNOTAVAIL;
 
         hlist_for_each_entry(cur_id, node, &bind_list->owners, node) {
-                cur_addr = (struct sockaddr *) &cur_id->id.route.addr.src_addr;
-                if (cma_any_addr(cur_addr))
-                        return -EADDRNOTAVAIL;
+                if (id_priv == cur_id)
+                        continue;
 
-                if (!cma_addr_cmp(addr, cur_addr))
-                        return -EADDRINUSE;
-        }
+                if ((cur_id->state == CMA_LISTEN) ||
+                    !reuseaddr || !cur_id->reuseaddr) {
+                        cur_addr = (struct sockaddr *) &cur_id->id.route.addr.src_addr;
+                        if (cma_any_addr(cur_addr))
+                                return -EADDRNOTAVAIL;
 
-        cma_bind_port(bind_list, id_priv);
+                        if (!cma_addr_cmp(addr, cur_addr))
+                                return -EADDRINUSE;
+                }
+        }
         return 0;
 }
 
+static int cma_use_port(struct idr *ps, struct rdma_id_private *id_priv)
+{
+        struct rdma_bind_list *bind_list;
+        unsigned short snum;
+        int ret;
+
+        snum = ntohs(cma_port((struct sockaddr *) &id_priv->id.route.addr.src_addr));
+        if (snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
+                return -EACCES;
+
+        bind_list = idr_find(ps, snum);
+        if (!bind_list) {
+                ret = cma_alloc_port(ps, id_priv, snum);
+        } else {
+                ret = cma_check_port(bind_list, id_priv, id_priv->reuseaddr);
+                if (!ret)
+                        cma_bind_port(bind_list, id_priv);
+        }
+        return ret;
+}
+
+static int cma_bind_listen(struct rdma_id_private *id_priv)
+{
+        struct rdma_bind_list *bind_list = id_priv->bind_list;
+        int ret = 0;
+
+        mutex_lock(&lock);
+        if (bind_list->owners.first->next)
+                ret = cma_check_port(bind_list, id_priv, 0);
+        mutex_unlock(&lock);
+        return ret;
+}
+
 static int cma_get_port(struct rdma_id_private *id_priv)
 {
         struct idr *ps;
@@ -2268,6 +2274,56 @@ static int cma_check_linklocal(struct rdma_dev_addr *dev_addr,
         return 0;
 }
 
+int rdma_listen(struct rdma_cm_id *id, int backlog)
+{
+        struct rdma_id_private *id_priv;
+        int ret;
+
+        id_priv = container_of(id, struct rdma_id_private, id);
+        if (id_priv->state == CMA_IDLE) {
+                ((struct sockaddr *) &id->route.addr.src_addr)->sa_family = AF_INET;
+                ret = rdma_bind_addr(id, (struct sockaddr *) &id->route.addr.src_addr);
+                if (ret)
+                        return ret;
+        }
+
+        if (!cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_LISTEN))
+                return -EINVAL;
+
+        if (id_priv->reuseaddr) {
+                ret = cma_bind_listen(id_priv);
+                if (ret)
+                        goto err;
+        }
+
+        id_priv->backlog = backlog;
+        if (id->device) {
+                switch (rdma_node_get_transport(id->device->node_type)) {
+                case RDMA_TRANSPORT_IB:
+                        ret = cma_ib_listen(id_priv);
+                        if (ret)
+                                goto err;
+                        break;
+                case RDMA_TRANSPORT_IWARP:
+                        ret = cma_iw_listen(id_priv, backlog);
+                        if (ret)
+                                goto err;
+                        break;
+                default:
+                        ret = -ENOSYS;
+                        goto err;
+                }
+        } else
+                cma_listen_on_all(id_priv);
+
+        return 0;
+err:
+        id_priv->backlog = 0;
+        cma_comp_exch(id_priv, CMA_LISTEN, CMA_ADDR_BOUND);
+        return ret;
+}
+EXPORT_SYMBOL(rdma_listen);
+
 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
 {
         struct rdma_id_private *id_priv;
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index ec1e9da1488b..b3fa798525b2 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -883,6 +883,13 @@ static int ucma_set_option_id(struct ucma_context *ctx, int optname,
                 }
                 rdma_set_service_type(ctx->cm_id, *((u8 *) optval));
                 break;
+        case RDMA_OPTION_ID_REUSEADDR:
+                if (optlen != sizeof(int)) {
+                        ret = -EINVAL;
+                        break;
+                }
+                ret = rdma_set_reuseaddr(ctx->cm_id, *((int *) optval) ? 1 : 0);
+                break;
         default:
                 ret = -ENOSYS;
         }