Merge branch 'rds-ipv6'

Ka-Cheong Poon says:

====================
rds: IPv6 support

This patch set adds IPv6 support to the kernel RDS and related
modules.  Existing RDS apps using IPv4 address continue to run without
any problem.  New RDS apps which want to use IPv6 address can do so by
passing the address in struct sockaddr_in6 to bind(), connect() or
sendmsg().  And those apps also need to use the new IPv6 equivalents
of some of the existing socket options as the existing options use a
32 bit integer to store IP address.

All RDS code now use struct in6_addr to store IP address.  IPv4
address is stored as an IPv4 mapped address.

Header file changes

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.

Internally, all RDS data structures which contain an IP address are
changed to use struct in6_addr to store the address. IPv4 address is
stored as an IPv4 mapped address. All the functions which take an IP
address as argument are also changed to use struct in6_addr.

RDS/RDMA/IB uses a private data (struct rds_ib_connect_private)
exchange between endpoints at RDS connection establishment time to
support RDMA. This private data exchange uses a 32 bit integer to
represent an IP address. This needs to be changed in order to support
IPv6. A new private data struct rds6_ib_connect_private is introduced
to handle this. To ensure backward compatibility, an IPv6 capable RDS
stack uses another RDMA listener port (RDS_CM_PORT) to accept IPv6
connection. And it continues to use the original RDS_PORT for IPv4 RDS
connections. When it needs to communicate with an IPv6 peer, it uses
the RDS_TCP_PORT to send the connection set up request.

RDS/TCP changes

TCP related code is changed to support IPv6.  Note that only an IPv6
TCP listener on port RDS_TCP_PORT is created as it can accept both
IPv4 and IPv6 connection requests.

IB/RDMA changes

The initial private data exchange between IB endpoints using RDMA is
changed to support IPv6 address instead, if the peer address is IPv6.
To ensure backward compatibility, annother RDMA listener port
(RDS_CM_PORT) is used to accept IPv6 connection. An IPv6 capable RDS
module continues to use the original RDS_PORT for IPv4 RDS
connections. When it needs to communicate with an IPv6 peer, it uses
the RDS_CM_PORT to send the connection set up request.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 103 insertions, 11 deletions

diff --git a/net/rds/ib.c b/net/rds/ib.c
index b6ad38e48f62..63d95ea7cdff 100644
--- a/net/rds/ib.c
+++ b/net/rds/ib.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006 Oracle.  All rights reserved.
+ * Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
@@ -39,6 +39,7 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <net/addrconf.h>
 
 #include "rds_single_path.h"
 #include "rds.h"
@@ -295,9 +296,11 @@ static int rds_ib_conn_info_visitor(struct rds_connection *conn,
 	/* We will only ever look at IB transports */
 	if (conn->c_trans != &rds_ib_transport)
 		return 0;
+	if (conn->c_isv6)
+		return 0;
 
-	iinfo->src_addr = conn->c_laddr;
-	iinfo->dst_addr = conn->c_faddr;
+	iinfo->src_addr = conn->c_laddr.s6_addr32[3];
+	iinfo->dst_addr = conn->c_faddr.s6_addr32[3];
 
 	memset(&iinfo->src_gid, 0, sizeof(iinfo->src_gid));
 	memset(&iinfo->dst_gid, 0, sizeof(iinfo->dst_gid));
@@ -318,6 +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)
@@ -330,6 +370,18 @@ 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
@@ -341,12 +393,17 @@ static void rds_ib_ic_info(struct socket *sock, unsigned int len,
  * allowed to influence which paths have priority.  We could call userspace
  * asserting this policy "routing".
  */
-static int rds_ib_laddr_check(struct net *net, __be32 addr)
+static int rds_ib_laddr_check(struct net *net, const struct in6_addr *addr,
+			      __u32 scope_id)
 {
 	int ret;
 	struct rdma_cm_id *cm_id;
+	struct sockaddr_in6 sin6;
 	struct sockaddr_in sin;
+	struct sockaddr *sa;
+	bool isv4;
 
+	isv4 = ipv6_addr_v4mapped(addr);
 	/* Create a CMA ID and try to bind it. This catches both
 	 * IB and iWARP capable NICs.
 	 */
@@ -355,21 +412,54 @@ static int rds_ib_laddr_check(struct net *net, __be32 addr)
 	if (IS_ERR(cm_id))
 		return PTR_ERR(cm_id);
 
-	memset(&sin, 0, sizeof(sin));
-	sin.sin_family = AF_INET;
-	sin.sin_addr.s_addr = addr;
+	if (isv4) {
+		memset(&sin, 0, sizeof(sin));
+		sin.sin_family = AF_INET;
+		sin.sin_addr.s_addr = addr->s6_addr32[3];
+		sa = (struct sockaddr *)&sin;
+	} else {
+		memset(&sin6, 0, sizeof(sin6));
+		sin6.sin6_family = AF_INET6;
+		sin6.sin6_addr = *addr;
+		sin6.sin6_scope_id = scope_id;
+		sa = (struct sockaddr *)&sin6;
+
+		/* XXX Do a special IPv6 link local address check here.  The
+		 * reason is that rdma_bind_addr() always succeeds with IPv6
+		 * link local address regardless it is indeed configured in a
+		 * system.
+		 */
+		if (ipv6_addr_type(addr) & IPV6_ADDR_LINKLOCAL) {
+			struct net_device *dev;
+
+			if (scope_id == 0)
+				return -EADDRNOTAVAIL;
+
+			/* Use init_net for now as RDS is not network
+			 * name space aware.
+			 */
+			dev = dev_get_by_index(&init_net, scope_id);
+			if (!dev)
+				return -EADDRNOTAVAIL;
+			if (!ipv6_chk_addr(&init_net, addr, dev, 1)) {
+				dev_put(dev);
+				return -EADDRNOTAVAIL;
+			}
+			dev_put(dev);
+		}
+	}
 
 	/* rdma_bind_addr will only succeed for IB & iWARP devices */
-	ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
+	ret = rdma_bind_addr(cm_id, sa);
 	/* due to this, we will claim to support iWARP devices unless we
 	   check node_type. */
 	if (ret || !cm_id->device ||
 	    cm_id->device->node_type != RDMA_NODE_IB_CA)
 		ret = -EADDRNOTAVAIL;
 
-	rdsdebug("addr %pI4 ret %d node type %d\n",
-		&addr, ret,
-		cm_id->device ? cm_id->device->node_type : -1);
+	rdsdebug("addr %pI6c%%%u ret %d node type %d\n",
+		 addr, scope_id, ret,
+		 cm_id->device ? cm_id->device->node_type : -1);
 
 	rdma_destroy_id(cm_id);
 
@@ -401,6 +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();
@@ -462,6 +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;