linux/net/rds
Sowmini Varadhan 241b271952 RDS-TCP: Reset tcp callbacks if re-using an outgoing socket in rds_tcp_accept_one()
Consider the following "duelling syn" sequence between two peers A and B:
        	A		B
        	SYN1     -->
        	    	<--	SYN2
        	SYN2ACK  -->

Note that the SYN/ACK has already been sent out by TCP before
rds_tcp_accept_one() gets invoked as part of callbacks.

If the inet_addr(A) is numerically less than inet_addr(B),
the arbitration scheme in rds_tcp_accept_one() will prefer the
TCP connection triggered by SYN1, and will send a CLOSE for the
SYN2 (just after the SYN2ACK was sent).

Since B also follows the same arbitration scheme, it will send the SYN-ACK
for SYN1 that will set up a healthy ESTABLISHED connection on both sides.
B will also get a  CLOSE for SYN2, which should result in the cleanup
of the TCP state machine for SYN2, but it should not trigger any
stale RDS-TCP callbacks (such as ->writespace, ->state_change etc),
that would disrupt the progress of the SYN2 based RDS-TCP  connection.

Thus the arbitration scheme in rds_tcp_accept_one() should restore
rds_tcp callbacks for the winner before setting them up for the
new accept socket, and also make sure that conn->c_outgoing
is set to 0 so that we do not trigger any reconnect attempts on the
passive side of the tcp socket in the future, in conformance with
commit c82ac7e69e ("net/rds: RDS-TCP: only initiate reconnect attempt
on outgoing TCP socket.")

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-13 04:22:41 -07:00
..
af_rds.c RDS: Use per-bucket rw lock for bind hash-table 2015-09-30 12:43:25 -04:00
bind.c RDS: Invoke ->laddr_check() in rds_bind() for explicitly bound transports. 2015-10-13 04:22:40 -07:00
cong.c rds: rds_cong_queue_updates needs to defer the congestion update transmission 2015-02-11 14:35:44 -08:00
connection.c RDS: Use a single TCP socket for both send and receive. 2015-10-05 03:34:51 -07:00
ib_cm.c RDS: IB: handle rds_ibdev release case instead of crashing the kernel 2015-10-05 11:19:01 -07:00
ib_rdma.c RDS: IB: split mr pool to improve 8K messages performance 2015-10-05 11:19:02 -07:00
ib_recv.c RDS: IB: ack more receive completions to improve performance 2015-10-05 11:19:01 -07:00
ib_ring.c
ib_send.c RDS: IB: split send completion handling and do batch ack 2015-10-05 11:19:01 -07:00
ib_stats.c RDS: IB: split mr pool to improve 8K messages performance 2015-10-05 11:19:02 -07:00
ib_sysctl.c net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
ib.c RDS: IB: split mr pool to improve 8K messages performance 2015-10-05 11:19:02 -07:00
ib.h RDS: IB: split mr pool to improve 8K messages performance 2015-10-05 11:19:02 -07:00
info.c rds: fix an integer overflow test in rds_info_getsockopt() 2015-08-03 15:20:16 -07:00
info.h
iw_cm.c RDS-TCP: Make RDS-TCP work correctly when it is set up in a netns other than init_net 2015-08-07 11:29:57 -07:00
iw_rdma.c RDS: Convert to ib_alloc_mr 2015-08-30 18:08:46 -04:00
iw_recv.c rds: switch ->inc_copy_to_user() to passing iov_iter 2014-11-24 05:16:43 -05:00
iw_ring.c
iw_send.c RDS: Convert to ib_alloc_mr 2015-08-30 18:08:46 -04:00
iw_stats.c
iw_sysctl.c rds: remove the unneed NULL checking 2014-05-09 15:59:45 -04:00
iw.c Changes for 4.3 2015-09-09 08:33:31 -07:00
iw.h rds: switch ->inc_copy_to_user() to passing iov_iter 2014-11-24 05:16:43 -05:00
Kconfig net/rds: remove depends on CONFIG_EXPERIMENTAL 2013-01-11 11:40:02 -08:00
loop.c RDS: use gfp flags from caller in conn_alloc() 2012-03-22 19:29:58 -04:00
loop.h
Makefile
message.c rds: Make rds_message_copy_from_user() return 0 on success. 2015-02-07 22:41:56 -08:00
page.c net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
rdma_transport.c RDS: check for valid cm_id before initiating connection 2015-08-25 13:35:31 -07:00
rdma_transport.h
rdma.c RDS: Fix rds MR reference count in rds_rdma_unuse() 2015-08-25 16:28:10 -07:00
rds.h Merge branch 'net/rds/4.3-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux 2015-10-08 04:38:37 -07:00
recv.c net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
send.c RDS: IB: split send completion handling and do batch ack 2015-10-05 11:19:01 -07:00
stats.c net/rds: zero last byte for strncpy 2013-03-08 00:35:44 -05:00
sysctl.c net: rds: use correct size for max unacked packets and bytes 2015-02-04 16:07:27 -08:00
tcp_connect.c RDS-TCP: Support multiple RDS-TCP listen endpoints, one per netns. 2015-08-07 11:29:58 -07:00
tcp_listen.c RDS-TCP: Reset tcp callbacks if re-using an outgoing socket in rds_tcp_accept_one() 2015-10-13 04:22:41 -07:00
tcp_recv.c rds: switch ->inc_copy_to_user() to passing iov_iter 2014-11-24 05:16:43 -05:00
tcp_send.c RDS-TCP: Set up MSG_MORE and MSG_SENDPAGE_NOTLAST as appropriate in rds_tcp_xmit 2015-10-05 03:34:53 -07:00
tcp_stats.c net: rds: fix const array syntax 2011-07-01 16:16:19 -07:00
tcp.c RDS-TCP: Do not bloat sndbuf/rcvbuf in rds_tcp_tune 2015-10-05 03:34:53 -07:00
tcp.h RDS-TCP: Support multiple RDS-TCP listen endpoints, one per netns. 2015-08-07 11:29:58 -07:00
threads.c RDS: use rds_send_xmit() state instead of RDS_LL_SEND_FULL 2015-10-05 11:19:01 -07:00
transport.c RDS-TCP: Make RDS-TCP work correctly when it is set up in a netns other than init_net 2015-08-07 11:29:57 -07:00