rds: Extend RDS API for IPv6 support

There are many data structures (RDS socket options) used by RDS apps
which use a 32 bit integer to store IP address. To support IPv6,
struct in6_addr needs to be used. To ensure backward compatibility, a
new data structure is introduced for each of those data structures
which use a 32 bit integer to represent an IP address. And new socket
options are introduced to use those new structures. This means that
existing apps should work without a problem with the new RDS module.
For apps which want to use IPv6, those new data structures and socket
options can be used. IPv4 mapped address is used to represent IPv4
address in the new data structures.

v4: Revert changes to SO_RDS_TRANSPORT

Signed-off-by: Ka-Cheong Poon <ka-cheong.poon@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 52 insertions, 0 deletions

diff --git a/net/rds/ib.c b/net/rds/ib.c
index 756225c5540f..63d95ea7cdff 100644
--- a/net/rds/ib.c
+++ b/net/rds/ib.c
@@ -321,6 +321,43 @@ static int rds_ib_conn_info_visitor(struct rds_connection *conn,
         return 1;
 }
 
+/* IPv6 version of rds_ib_conn_info_visitor(). */
+static int rds6_ib_conn_info_visitor(struct rds_connection *conn,
+                                     void *buffer)
+{
+        struct rds6_info_rdma_connection *iinfo6 = buffer;
+        struct rds_ib_connection *ic;
+
+        /* We will only ever look at IB transports */
+        if (conn->c_trans != &rds_ib_transport)
+                return 0;
+
+        iinfo6->src_addr = conn->c_laddr;
+        iinfo6->dst_addr = conn->c_faddr;
+
+        memset(&iinfo6->src_gid, 0, sizeof(iinfo6->src_gid));
+        memset(&iinfo6->dst_gid, 0, sizeof(iinfo6->dst_gid));
+
+        if (rds_conn_state(conn) == RDS_CONN_UP) {
+                struct rds_ib_device *rds_ibdev;
+                struct rdma_dev_addr *dev_addr;
+
+                ic = conn->c_transport_data;
+                dev_addr = &ic->i_cm_id->route.addr.dev_addr;
+                rdma_addr_get_sgid(dev_addr,
+                                   (union ib_gid *)&iinfo6->src_gid);
+                rdma_addr_get_dgid(dev_addr,
+                                   (union ib_gid *)&iinfo6->dst_gid);
+
+                rds_ibdev = ic->rds_ibdev;
+                iinfo6->max_send_wr = ic->i_send_ring.w_nr;
+                iinfo6->max_recv_wr = ic->i_recv_ring.w_nr;
+                iinfo6->max_send_sge = rds_ibdev->max_sge;
+                rds6_ib_get_mr_info(rds_ibdev, iinfo6);
+        }
+        return 1;
+}
+
 static void rds_ib_ic_info(struct socket *sock, unsigned int len,
                            struct rds_info_iterator *iter,
                            struct rds_info_lengths *lens)
@@ -333,6 +370,19 @@ static void rds_ib_ic_info(struct socket *sock, unsigned int len,
                                 sizeof(struct rds_info_rdma_connection));
 }
 
+/* IPv6 version of rds_ib_ic_info(). */
+static void rds6_ib_ic_info(struct socket *sock, unsigned int len,
+                            struct rds_info_iterator *iter,
+                            struct rds_info_lengths *lens)
+{
+        u64 buffer[(sizeof(struct rds6_info_rdma_connection) + 7) / 8];
+
+        rds_for_each_conn_info(sock, len, iter, lens,
+                               rds6_ib_conn_info_visitor,
+                               buffer,
+                               sizeof(struct rds6_info_rdma_connection));
+}
+
 /*
  * Early RDS/IB was built to only bind to an address if there is an IPoIB
  * device with that address set.
@@ -441,6 +491,7 @@ void rds_ib_exit(void)
         rds_ib_set_unloading();
         synchronize_rcu();
         rds_info_deregister_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
+        rds_info_deregister_func(RDS6_INFO_IB_CONNECTIONS, rds6_ib_ic_info);
         rds_ib_unregister_client();
         rds_ib_destroy_nodev_conns();
         rds_ib_sysctl_exit();
@@ -502,6 +553,7 @@ int rds_ib_init(void)
         rds_trans_register(&rds_ib_transport);
 
         rds_info_register_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
+        rds_info_register_func(RDS6_INFO_IB_CONNECTIONS, rds6_ib_ic_info);
 
         goto out;