RDMA/cma: Remove padding arrays by using struct sockaddr_storage

There are a few places where the RDMA CM code handles IPv6 by doing

	struct sockaddr		addr;
	u8			pad[sizeof(struct sockaddr_in6) -
				    sizeof(struct sockaddr)];

This is fragile and ugly; handle this in a better way with just

	struct sockaddr_storage	addr;

[ Also roll in patch from Aleksey Senin <alekseys@voltaire.com> to
  switch to struct sockaddr_storage and get rid of padding arrays in
  struct rdma_addr. ]

Signed-off-by: Roland Dreier <rolandd@cisco.com>

3 files changed, 26 insertions, 33 deletions

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index e980ff3335db..d951896ff7fc 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -155,9 +155,7 @@ struct cma_multicast {
         } multicast;
         struct list_head        list;
         void                    *context;
-        struct sockaddr         addr;
-        u8                      pad[sizeof(struct sockaddr_in6) -
-                                    sizeof(struct sockaddr)];
+        struct sockaddr_storage addr;
 };
 
 struct cma_work {
@@ -786,8 +784,8 @@ static void cma_cancel_operation(struct rdma_id_private *id_priv,
                 cma_cancel_route(id_priv);
                 break;
         case CMA_LISTEN:
-                if (cma_any_addr(&id_priv->id.route.addr.src_addr) &&
-                    !id_priv->cma_dev)
+                if (cma_any_addr((struct sockaddr *) &id_priv->id.route.addr.src_addr)
+                                && !id_priv->cma_dev)
                         cma_cancel_listens(id_priv);
                 break;
         default:
@@ -1026,7 +1024,7 @@ static struct rdma_id_private *cma_new_conn_id(struct rdma_cm_id *listen_id,
                 rt->path_rec[1] = *ib_event->param.req_rcvd.alternate_path;
 
         ib_addr_set_dgid(&rt->addr.dev_addr, &rt->path_rec[0].dgid);
-        ret = rdma_translate_ip(&id->route.addr.src_addr,
+        ret = rdma_translate_ip((struct sockaddr *) &id->route.addr.src_addr,
                                 &id->route.addr.dev_addr);
         if (ret)
                 goto destroy_id;
@@ -1064,7 +1062,7 @@ static struct rdma_id_private *cma_new_udp_id(struct rdma_cm_id *listen_id,
         cma_save_net_info(&id->route.addr, &listen_id->route.addr,
                           ip_ver, port, src, dst);
 
-        ret = rdma_translate_ip(&id->route.addr.src_addr,
+        ret = rdma_translate_ip((struct sockaddr *) &id->route.addr.src_addr,
                                 &id->route.addr.dev_addr);
         if (ret)
                 goto err;
@@ -1377,7 +1375,7 @@ static int cma_ib_listen(struct rdma_id_private *id_priv)
         if (IS_ERR(id_priv->cm_id.ib))
                 return PTR_ERR(id_priv->cm_id.ib);
 
-        addr = &id_priv->id.route.addr.src_addr;
+        addr = (struct sockaddr *) &id_priv->id.route.addr.src_addr;
         svc_id = cma_get_service_id(id_priv->id.ps, addr);
         if (cma_any_addr(addr))
                 ret = ib_cm_listen(id_priv->cm_id.ib, svc_id, 0, NULL);
@@ -1443,7 +1441,7 @@ static void cma_listen_on_dev(struct rdma_id_private *id_priv,
 
         dev_id_priv->state = CMA_ADDR_BOUND;
         memcpy(&id->route.addr.src_addr, &id_priv->id.route.addr.src_addr,
-               ip_addr_size(&id_priv->id.route.addr.src_addr));
+               ip_addr_size((struct sockaddr *) &id_priv->id.route.addr.src_addr));
 
         cma_attach_to_dev(dev_id_priv, cma_dev);
         list_add_tail(&dev_id_priv->listen_list, &id_priv->listen_list);
@@ -1563,13 +1561,14 @@ static int cma_query_ib_route(struct rdma_id_private *id_priv, int timeout_ms,
         path_rec.pkey = cpu_to_be16(ib_addr_get_pkey(&addr->dev_addr));
         path_rec.numb_path = 1;
         path_rec.reversible = 1;
-        path_rec.service_id = cma_get_service_id(id_priv->id.ps, &addr->dst_addr);
+        path_rec.service_id = cma_get_service_id(id_priv->id.ps,
+                                                        (struct sockaddr *) &addr->dst_addr);
 
         comp_mask = IB_SA_PATH_REC_DGID | IB_SA_PATH_REC_SGID |
                     IB_SA_PATH_REC_PKEY | IB_SA_PATH_REC_NUMB_PATH |
                     IB_SA_PATH_REC_REVERSIBLE | IB_SA_PATH_REC_SERVICE_ID;
 
-        if (addr->src_addr.sa_family == AF_INET) {
+        if (addr->src_addr.ss_family == AF_INET) {
                 path_rec.qos_class = cpu_to_be16((u16) id_priv->tos);
                 comp_mask |= IB_SA_PATH_REC_QOS_CLASS;
         } else {
@@ -1848,7 +1847,7 @@ static int cma_resolve_loopback(struct rdma_id_private *id_priv)
         ib_addr_get_sgid(&id_priv->id.route.addr.dev_addr, &gid);
         ib_addr_set_dgid(&id_priv->id.route.addr.dev_addr, &gid);
 
-        if (cma_zero_addr(&id_priv->id.route.addr.src_addr)) {
+        if (cma_zero_addr((struct sockaddr *) &id_priv->id.route.addr.src_addr)) {
                 src_in = (struct sockaddr_in *)&id_priv->id.route.addr.src_addr;
                 dst_in = (struct sockaddr_in *)&id_priv->id.route.addr.dst_addr;
                 src_in->sin_family = dst_in->sin_family;
@@ -1897,7 +1896,7 @@ int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
         if (cma_any_addr(dst_addr))
                 ret = cma_resolve_loopback(id_priv);
         else
-                ret = rdma_resolve_ip(&addr_client, &id->route.addr.src_addr,
+                ret = rdma_resolve_ip(&addr_client, (struct sockaddr *) &id->route.addr.src_addr,
                                       dst_addr, &id->route.addr.dev_addr,
                                       timeout_ms, addr_handler, id_priv);
         if (ret)
@@ -2021,11 +2020,11 @@ static int cma_use_port(struct idr *ps, struct rdma_id_private *id_priv)
          * We don't support binding to any address if anyone is bound to
          * a specific address on the same port.
          */
-        if (cma_any_addr(&id_priv->id.route.addr.src_addr))
+        if (cma_any_addr((struct sockaddr *) &id_priv->id.route.addr.src_addr))
                 return -EADDRNOTAVAIL;
 
         hlist_for_each_entry(cur_id, node, &bind_list->owners, node) {
-                if (cma_any_addr(&cur_id->id.route.addr.src_addr))
+                if (cma_any_addr((struct sockaddr *) &cur_id->id.route.addr.src_addr))
                         return -EADDRNOTAVAIL;
 
                 cur_sin = (struct sockaddr_in *) &cur_id->id.route.addr.src_addr;
@@ -2060,7 +2059,7 @@ static int cma_get_port(struct rdma_id_private *id_priv)
         }
 
         mutex_lock(&lock);
-        if (cma_any_port(&id_priv->id.route.addr.src_addr))
+        if (cma_any_port((struct sockaddr *) &id_priv->id.route.addr.src_addr))
                 ret = cma_alloc_any_port(ps, id_priv);
         else
                 ret = cma_use_port(ps, id_priv);
@@ -2232,7 +2231,7 @@ static int cma_resolve_ib_udp(struct rdma_id_private *id_priv,
 
         req.path = route->path_rec;
         req.service_id = cma_get_service_id(id_priv->id.ps,
-                                            &route->addr.dst_addr);
+                                            (struct sockaddr *) &route->addr.dst_addr);
         req.timeout_ms = 1 << (CMA_CM_RESPONSE_TIMEOUT - 8);
         req.max_cm_retries = CMA_MAX_CM_RETRIES;
 
@@ -2283,7 +2282,7 @@ static int cma_connect_ib(struct rdma_id_private *id_priv,
                 req.alternate_path = &route->path_rec[1];
 
         req.service_id = cma_get_service_id(id_priv->id.ps,
-                                            &route->addr.dst_addr);
+                                            (struct sockaddr *) &route->addr.dst_addr);
         req.qp_num = id_priv->qp_num;
         req.qp_type = IB_QPT_RC;
         req.starting_psn = id_priv->seq_num;
@@ -2667,7 +2666,7 @@ static int cma_join_ib_multicast(struct rdma_id_private *id_priv,
         if (ret)
                 return ret;
 
-        cma_set_mgid(id_priv, &mc->addr, &rec.mgid);
+        cma_set_mgid(id_priv, (struct sockaddr *) &mc->addr, &rec.mgid);
         if (id_priv->id.ps == RDMA_PS_UDP)
                 rec.qkey = cpu_to_be32(RDMA_UDP_QKEY);
         ib_addr_get_sgid(dev_addr, &rec.port_gid);
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index b41dd26bbfa1..3ddacf39b7ba 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -81,9 +81,7 @@ struct ucma_multicast {
 
         u64                     uid;
         struct list_head        list;
-        struct sockaddr         addr;
-        u8                      pad[sizeof(struct sockaddr_in6) -
-                                    sizeof(struct sockaddr)];
+        struct sockaddr_storage addr;
 };
 
 struct ucma_event {
@@ -603,11 +601,11 @@ static ssize_t ucma_query_route(struct ucma_file *file,
                 return PTR_ERR(ctx);
 
         memset(&resp, 0, sizeof resp);
-        addr = &ctx->cm_id->route.addr.src_addr;
+        addr = (struct sockaddr *) &ctx->cm_id->route.addr.src_addr;
         memcpy(&resp.src_addr, addr, addr->sa_family == AF_INET ?
                                      sizeof(struct sockaddr_in) :
                                      sizeof(struct sockaddr_in6));
-        addr = &ctx->cm_id->route.addr.dst_addr;
+        addr = (struct sockaddr *) &ctx->cm_id->route.addr.dst_addr;
         memcpy(&resp.dst_addr, addr, addr->sa_family == AF_INET ?
                                      sizeof(struct sockaddr_in) :
                                      sizeof(struct sockaddr_in6));
@@ -913,7 +911,7 @@ static ssize_t ucma_join_multicast(struct ucma_file *file,
 
         mc->uid = cmd.uid;
         memcpy(&mc->addr, &cmd.addr, sizeof cmd.addr);
-        ret = rdma_join_multicast(ctx->cm_id, &mc->addr, mc);
+        ret = rdma_join_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr, mc);
         if (ret)
                 goto err2;
 
@@ -929,7 +927,7 @@ static ssize_t ucma_join_multicast(struct ucma_file *file,
         return 0;
 
 err3:
-        rdma_leave_multicast(ctx->cm_id, &mc->addr);
+        rdma_leave_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr);
         ucma_cleanup_mc_events(mc);
 err2:
         mutex_lock(&mut);
@@ -975,7 +973,7 @@ static ssize_t ucma_leave_multicast(struct ucma_file *file,
                 goto out;
         }
 
-        rdma_leave_multicast(mc->ctx->cm_id, &mc->addr);
+        rdma_leave_multicast(mc->ctx->cm_id, (struct sockaddr *) &mc->addr);
         mutex_lock(&mc->ctx->file->mut);
         ucma_cleanup_mc_events(mc);
         list_del(&mc->list);
diff --git a/include/rdma/rdma_cm.h b/include/rdma/rdma_cm.h
index df7faf09d66f..c6b2962315b3 100644
--- a/include/rdma/rdma_cm.h
+++ b/include/rdma/rdma_cm.h
@@ -71,12 +71,8 @@ enum rdma_port_space {
 };
 
 struct rdma_addr {
-        struct sockaddr src_addr;
-        u8              src_pad[sizeof(struct sockaddr_in6) -
-                                sizeof(struct sockaddr)];
-        struct sockaddr dst_addr;
-        u8              dst_pad[sizeof(struct sockaddr_in6) -
-                                sizeof(struct sockaddr)];
+        struct sockaddr_storage src_addr;
+        struct sockaddr_storage dst_addr;
         struct rdma_dev_addr dev_addr;
 };