Merge tag 'rxrpc-devel-20140304' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
net-next: AF_RXRPC fixes and development

Here are some AF_RXRPC fixes:

 (1) Fix to remove incorrect checksum calculation made during recvmsg().  It's
     unnecessary to try to do this there since we check the checksum before
     reading the RxRPC header from the packet.

 (2) Fix to prevent the sending of an ABORT packet in response to another
     ABORT packet and inducing a storm.

 (3) Fix UDP MTU calculation from parsing ICMP_FRAG_NEEDED packets where we
     don't handle the ICMP packet not specifying an MTU size.

And development patches:

 (4) Add sysctls for configuring RxRPC parameters, specifically various delays
     pertaining to ACK generation, the time before we resend a packet for
     which we don't receive an ACK, the maximum time a call is permitted to
     live and the amount of time transport, connection and dead call
     information is cached.

 (5) Improve ACK packet production by adjusting the handling of ACK_REQUESTED
     packets, ignoring the MORE_PACKETS flag, delaying the production of
     otherwise immediate ACK_IDLE packets and delaying all ACK_IDLE production
     (barring the call termination) to half a second.

 (6) Add more sysctl parameters to expose the Rx window size, the maximum
     packet size that we're willing to receive and the number of jumbo rxrpc
     packets we're willing to handle in a single UDP packet.

 (7) Request ACKs on alternate DATA packets so that the other side doesn't
     wait till we fill up the Tx window.

 (8) Use a RCU hash table to look up the rxrpc_call for an incoming packet
     rather than stepping through a hierarchy involving several spinlocks.
====================

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

1 files changed, 11 insertions, 4 deletions

diff --git a/net/rxrpc/ar-output.c b/net/rxrpc/ar-output.c
index d0e8f1c1898a..0b4b9a79f5ab 100644
--- a/net/rxrpc/ar-output.c
+++ b/net/rxrpc/ar-output.c
@@ -18,7 +18,10 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
-int rxrpc_resend_timeout = 4;
+/*
+ * Time till packet resend (in jiffies).
+ */
+unsigned rxrpc_resend_timeout = 4 * HZ;
 
 static int rxrpc_send_data(struct kiocb *iocb,
 			   struct rxrpc_sock *rx,
@@ -487,7 +490,7 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
 	       ntohl(sp->hdr.serial), ntohl(sp->hdr.seq));
 
 	sp->need_resend = false;
-	sp->resend_at = jiffies + rxrpc_resend_timeout * HZ;
+	sp->resend_at = jiffies + rxrpc_resend_timeout;
 	if (!test_and_set_bit(RXRPC_CALL_RUN_RTIMER, &call->flags)) {
 		_debug("run timer");
 		call->resend_timer.expires = sp->resend_at;
@@ -666,6 +669,7 @@ static int rxrpc_send_data(struct kiocb *iocb,
 		/* add the packet to the send queue if it's now full */
 		if (sp->remain <= 0 || (segment == 0 && !more)) {
 			struct rxrpc_connection *conn = call->conn;
+			uint32_t seq;
 			size_t pad;
 
 			/* pad out if we're using security */
@@ -678,11 +682,12 @@ static int rxrpc_send_data(struct kiocb *iocb,
 					memset(skb_put(skb, pad), 0, pad);
 			}
 
+			seq = atomic_inc_return(&call->sequence);
+
 			sp->hdr.epoch = conn->epoch;
 			sp->hdr.cid = call->cid;
 			sp->hdr.callNumber = call->call_id;
-			sp->hdr.seq =
-				htonl(atomic_inc_return(&call->sequence));
+			sp->hdr.seq = htonl(seq);
 			sp->hdr.serial =
 				htonl(atomic_inc_return(&conn->serial));
 			sp->hdr.type = RXRPC_PACKET_TYPE_DATA;
@@ -697,6 +702,8 @@ static int rxrpc_send_data(struct kiocb *iocb,
 			else if (CIRC_SPACE(call->acks_head, call->acks_tail,
 					    call->acks_winsz) > 1)
 				sp->hdr.flags |= RXRPC_MORE_PACKETS;
+			if (more && seq & 1)
+				sp->hdr.flags |= RXRPC_REQUEST_ACK;
 
 			ret = rxrpc_secure_packet(
 				call, skb, skb->mark,