BMC/Intel-BMC/linux.git/net/rds/tcp_connect.c, branch dev

net/rds: RDS-TCP: Always create a new rds_sock for an incoming connection.

2015-05-09T20:03:27+00:00

When running RDS over TCP, the active (client) side connects to the listening ("passive") side at the RDS_TCP_PORT. After the connection is established, if the client side reboots (potentially without even sending a FIN) the server still has a TCP socket in the esablished state. If the server-side now gets a new SYN comes from the client with a different client port, TCP will create a new socket-pair, but the RDS layer will incorrectly pull up the old rds_connection (which is still associated with the stale t_sock and RDS socket state). This patch corrects this behavior by having rds_tcp_accept_one() always create a new connection for an incoming TCP SYN. The rds and tcp state associated with the old socket-pair is cleaned up via the rds_tcp_state_change() callback which would typically be invoked in most cases when the client-TCP sends a FIN on TCP restart, triggering a transition to CLOSE_WAIT state. In the rarer event of client death without a FIN, TCP_KEEPALIVE probes on the socket will detect the stale socket, and the TCP transition to CLOSE state will trigger the RDS state cleanup. Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller

net/rds: do proper house keeping if connection fails in rds_tcp_conn_connect

2014-10-03T19:51:59+00:00

I see two problems if we consider the sock->ops->connect attempt to fail in rds_tcp_conn_connect. The first issue is that for example we don't remove the previously added rds_tcp_connection item to rds_tcp_tc_list at rds_tcp_set_callbacks, which means that on a next reconnect attempt for the same rds_connection, when rds_tcp_conn_connect is called we can again call rds_tcp_set_callbacks, resulting in duplicated items on rds_tcp_tc_list, leading to list corruption: to avoid this just make sure we call properly rds_tcp_restore_callbacks before we exit. The second issue is that we should also release the sock properly, by setting sock = NULL only if we are returning without error. Signed-off-by: Herton R. Krzesinski Signed-off-by: David S. Miller

rds: Don't disable BH on BH context

2012-08-23T05:52:04+00:00

Since we have already in BH context when *_write_space(), *_data_ready() as well as *_state_change() are called, it's unnecessary to disable BH. Signed-off-by: Ying Xue Signed-off-by: David S. Miller

Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

2010-09-27T08:03:03+00:00

Conflicts: drivers/net/qlcnic/qlcnic_init.c net/ipv4/ip_output.c

net: fix a lockdep splat

2010-09-25T05:26:10+00:00

We have for each socket : One spinlock (sk_slock.slock) One rwlock (sk_callback_lock) Possible scenarios are : (A) (this is used in net/sunrpc/xprtsock.c) read_lock(&sk->sk_callback_lock) (without blocking BH) spin_lock(&sk->sk_slock.slock); ... read_lock(&sk->sk_callback_lock); ... (B) write_lock_bh(&sk->sk_callback_lock) stuff write_unlock_bh(&sk->sk_callback_lock) (C) spin_lock_bh(&sk->sk_slock) ... write_lock_bh(&sk->sk_callback_lock) stuff write_unlock_bh(&sk->sk_callback_lock) spin_unlock_bh(&sk->sk_slock) This (C) case conflicts with (A) : CPU1 [A] CPU2 [C] read_lock(callback_lock) spin_lock_bh(slock) We have one problematic (C) use case in inet_csk_listen_stop() : local_bh_disable(); bh_lock_sock(child); // spin_lock_bh(&sk->sk_slock) WARN_ON(sock_owned_by_user(child)); ... sock_orphan(child); // write_lock_bh(&sk->sk_callback_lock) lockdep is not happy with this, as reported by Tetsuo Handa It seems only way to deal with this is to use read_lock_bh(callbacklock) everywhere. Thanks to Jarek for pointing a bug in my first attempt and suggesting this solution. Reported-by: Tetsuo Handa Tested-by: Tetsuo Handa Signed-off-by: Eric Dumazet CC: Jarek Poplawski Tested-by: Eric Dumazet Signed-off-by: David S. Miller

RDS: cleanup: remove "== NULL"s and "!= NULL"s in ptr comparisons

2010-09-09T01:11:32+00:00

Favor "if (foo)" style over "if (foo != NULL)". Signed-off-by: Andy Grover

net: Remove unnecessary semicolons after switch statements

2010-05-18T00:44:35+00:00

Also added an explicit break; to avoid a fallthrough in net/ipv4/tcp_input.c Signed-off-by: Joe Perches Signed-off-by: David S. Miller

net/rds: remove uses of NIPQUAD, use %pI4

2010-02-04T04:16:48+00:00

Signed-off-by: Joe Perches Cc: Andy Grover Signed-off-by: Andrew Morton Signed-off-by: David S. Miller

RDS: Add TCP transport to RDS

2009-08-24T02:13:02+00:00

This code allows RDS to be tunneled over a TCP connection. RDMA operations are disabled when using TCP transport, but this frees RDS from the IB/RDMA stack dependency, and allows it to be used with standard Ethernet adapters, or in a VM. Signed-off-by: Andy Grover Signed-off-by: David S. Miller