Merge tag 'rxrpc-rewrite-20160622-2' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Get rid of conn bundle and transport structs

Here's the next part of the AF_RXRPC rewrite.  The primary purpose of this
set is to get rid of the rxrpc_conn_bundle and rxrpc_transport structs.
This simplifies things for future development of the connection handling.

To this end, the following significant changes are made:

 (1) The rxrpc_connection struct is given pointers to the local and peer
     endpoints, inside the rxrpc_conn_parameters struct.  Pointers to the
     transport's copy of these pointers are then redirected to the
     connection struct.

 (2) Exclusive connection handling is fixed.  Exclusive connections should
     do just one call and then be retired.  They are used in security
     negotiations and, I believe, the idea is to avoid reuse of negotiated
     security contexts.

     The current code is doing a single connection per socket and doing all
     the calls over that.  With this change it gets a new connection for
     each call made.

 (3) A new sendmsg() control message marker is added to make individual
     calls operate over exclusive connections.  This should be used in
     future in preference to the sockopt that marks a socket as "exclusive
     connection".

 (4) IDs for client connections initiated by a machine are now allocated
     from a global pool using the IDR facility and are unique across all
     client connections, no matter their destination.  The IDR facility is
     then used to look up a connection on the connection ID alone.  Other
     parameters are then verified afterwards.

     Note that the IDR facility may use a lot of memory if the IDs it holds
     are widely scattered.  Given this, in a future commit, client
     connections will be retired if they are more than a certain distance
     from the last ID allocated.

     The client epoch is advanced by 1 each time the client ID counter
     wraps.  Connections outside the current epoch will also be retired in
     a future commit.

 (5) The connection bundle concept is removed and the client connection
     tree is moved into the local endpoint.  The queue for waiting for a
     call channel is moved to the rxrpc_connection struct as there can only
     be one connection for any particular key going to any particular peer
     now.

 (6) The rxrpc_transport struct is removed and the service connection tree
     is moved into the peer struct.
====================

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

1 files changed, 52 insertions, 57 deletions

diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index e6fb3863b0bc..f4bda06b7d2d 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -35,7 +35,8 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
 			      unsigned long *user_call_ID,
 			      enum rxrpc_command *command,
-			      u32 *abort_code)
+			      u32 *abort_code,
+			      bool *_exclusive)
 {
 	struct cmsghdr *cmsg;
 	bool got_user_ID = false;
@@ -93,6 +94,11 @@ static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
 				return -EINVAL;
 			break;
 
+		case RXRPC_EXCLUSIVE_CALL:
+			*_exclusive = true;
+			if (len != 0)
+				return -EINVAL;
+			break;
 		default:
 			return -EINVAL;
 		}
@@ -131,13 +137,11 @@ static void rxrpc_send_abort(struct rxrpc_call *call, u32 abort_code)
  */
 static struct rxrpc_call *
 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
-				  unsigned long user_call_ID)
+				  unsigned long user_call_ID, bool exclusive)
 {
-	struct rxrpc_conn_bundle *bundle;
-	struct rxrpc_transport *trans;
+	struct rxrpc_conn_parameters cp;
 	struct rxrpc_call *call;
 	struct key *key;
-	long ret;
 
 	DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
 
@@ -146,39 +150,20 @@ rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 	if (!msg->msg_name)
 		return ERR_PTR(-EDESTADDRREQ);
 
-	trans = rxrpc_name_to_transport(rx, msg->msg_name, msg->msg_namelen, 0,
-					GFP_KERNEL);
-	if (IS_ERR(trans)) {
-		ret = PTR_ERR(trans);
-		goto out;
-	}
-
 	key = rx->key;
 	if (key && !rx->key->payload.data[0])
 		key = NULL;
-	bundle = rxrpc_get_bundle(rx, trans, key, srx->srx_service, GFP_KERNEL);
-	if (IS_ERR(bundle)) {
-		ret = PTR_ERR(bundle);
-		goto out_trans;
-	}
 
-	call = rxrpc_new_client_call(rx, trans, bundle, user_call_ID,
-				     GFP_KERNEL);
-	rxrpc_put_bundle(trans, bundle);
-	rxrpc_put_transport(trans);
-	if (IS_ERR(call)) {
-		ret = PTR_ERR(call);
-		goto out_trans;
-	}
+	memset(&cp, 0, sizeof(cp));
+	cp.local		= rx->local;
+	cp.key			= rx->key;
+	cp.security_level	= rx->min_sec_level;
+	cp.exclusive		= rx->exclusive | exclusive;
+	cp.service_id		= srx->srx_service;
+	call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, GFP_KERNEL);
 
 	_leave(" = %p\n", call);
 	return call;
-
-out_trans:
-	rxrpc_put_transport(trans);
-out:
-	_leave(" = %ld", ret);
-	return ERR_PTR(ret);
 }
 
 /*
@@ -191,12 +176,14 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 	enum rxrpc_command cmd;
 	struct rxrpc_call *call;
 	unsigned long user_call_ID = 0;
+	bool exclusive = false;
 	u32 abort_code = 0;
 	int ret;
 
 	_enter("");
 
-	ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code);
+	ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code,
+				 &exclusive);
 	if (ret < 0)
 		return ret;
 
@@ -214,7 +201,8 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 	if (!call) {
 		if (cmd != RXRPC_CMD_SEND_DATA)
 			return -EBADSLT;
-		call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID);
+		call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID,
+							 exclusive);
 		if (IS_ERR(call))
 			return PTR_ERR(call);
 	}
@@ -319,7 +307,7 @@ EXPORT_SYMBOL(rxrpc_kernel_abort_call);
 /*
  * send a packet through the transport endpoint
  */
-int rxrpc_send_packet(struct rxrpc_transport *trans, struct sk_buff *skb)
+int rxrpc_send_data_packet(struct rxrpc_connection *conn, struct sk_buff *skb)
 {
 	struct kvec iov[1];
 	struct msghdr msg;
@@ -330,30 +318,30 @@ int rxrpc_send_packet(struct rxrpc_transport *trans, struct sk_buff *skb)
 	iov[0].iov_base = skb->head;
 	iov[0].iov_len = skb->len;
 
-	msg.msg_name = &trans->peer->srx.transport.sin;
-	msg.msg_namelen = sizeof(trans->peer->srx.transport.sin);
+	msg.msg_name = &conn->params.peer->srx.transport;
+	msg.msg_namelen = conn->params.peer->srx.transport_len;
 	msg.msg_control = NULL;
 	msg.msg_controllen = 0;
 	msg.msg_flags = 0;
 
 	/* send the packet with the don't fragment bit set if we currently
 	 * think it's small enough */
-	if (skb->len - sizeof(struct rxrpc_wire_header) < trans->peer->maxdata) {
-		down_read(&trans->local->defrag_sem);
+	if (skb->len - sizeof(struct rxrpc_wire_header) < conn->params.peer->maxdata) {
+		down_read(&conn->params.local->defrag_sem);
 		/* send the packet by UDP
 		 * - returns -EMSGSIZE if UDP would have to fragment the packet
 		 *   to go out of the interface
 		 *   - in which case, we'll have processed the ICMP error
 		 *     message and update the peer record
 		 */
-		ret = kernel_sendmsg(trans->local->socket, &msg, iov, 1,
+		ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 1,
 				     iov[0].iov_len);
 
-		up_read(&trans->local->defrag_sem);
+		up_read(&conn->params.local->defrag_sem);
 		if (ret == -EMSGSIZE)
 			goto send_fragmentable;
 
-		_leave(" = %d [%u]", ret, trans->peer->maxdata);
+		_leave(" = %d [%u]", ret, conn->params.peer->maxdata);
 		return ret;
 	}
 
@@ -361,21 +349,28 @@ send_fragmentable:
 	/* attempt to send this message with fragmentation enabled */
 	_debug("send fragment");
 
-	down_write(&trans->local->defrag_sem);
-	opt = IP_PMTUDISC_DONT;
-	ret = kernel_setsockopt(trans->local->socket, SOL_IP, IP_MTU_DISCOVER,
-				(char *) &opt, sizeof(opt));
-	if (ret == 0) {
-		ret = kernel_sendmsg(trans->local->socket, &msg, iov, 1,
-				     iov[0].iov_len);
-
-		opt = IP_PMTUDISC_DO;
-		kernel_setsockopt(trans->local->socket, SOL_IP,
-				  IP_MTU_DISCOVER, (char *) &opt, sizeof(opt));
+	down_write(&conn->params.local->defrag_sem);
+
+	switch (conn->params.local->srx.transport.family) {
+	case AF_INET:
+		opt = IP_PMTUDISC_DONT;
+		ret = kernel_setsockopt(conn->params.local->socket,
+					SOL_IP, IP_MTU_DISCOVER,
+					(char *)&opt, sizeof(opt));
+		if (ret == 0) {
+			ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 1,
+					     iov[0].iov_len);
+
+			opt = IP_PMTUDISC_DO;
+			kernel_setsockopt(conn->params.local->socket, SOL_IP,
+					  IP_MTU_DISCOVER,
+					  (char *)&opt, sizeof(opt));
+		}
+		break;
 	}
 
-	up_write(&trans->local->defrag_sem);
-	_leave(" = %d [frag %u]", ret, trans->peer->maxdata);
+	up_write(&conn->params.local->defrag_sem);
+	_leave(" = %d [frag %u]", ret, conn->params.peer->maxdata);
 	return ret;
 }
 
@@ -487,7 +482,7 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
 	if (try_to_del_timer_sync(&call->ack_timer) >= 0) {
 		/* the packet may be freed by rxrpc_process_call() before this
 		 * returns */
-		ret = rxrpc_send_packet(call->conn->trans, skb);
+		ret = rxrpc_send_data_packet(call->conn, skb);
 		_net("sent skb %p", skb);
 	} else {
 		_debug("failed to delete ACK timer");
@@ -573,7 +568,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 					goto maybe_error;
 			}
 
-			max = call->conn->trans->peer->maxdata;
+			max = call->conn->params.peer->maxdata;
 			max -= call->conn->security_size;
 			max &= ~(call->conn->size_align - 1UL);
 
@@ -664,7 +659,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 
 			seq = atomic_inc_return(&call->sequence);
 
-			sp->hdr.epoch	= conn->epoch;
+			sp->hdr.epoch	= conn->proto.epoch;
 			sp->hdr.cid	= call->cid;
 			sp->hdr.callNumber = call->call_id;
 			sp->hdr.seq	= seq;