2008-01-25 16:59:49

by Myklebust, Trond

[permalink] [raw]
Subject: [PATCH 007/112] SUNRPC: Allow the client to detect if the TCP connection is closed

Add an xprt->state bit to enable the TCP ->state_change() method to signal
whether or not the TCP connection is in the process of closing down.
This will to be used by the reconnection logic in a separate patch.

Signed-off-by: Trond Myklebust <[email protected]>
---

include/linux/sunrpc/xprt.h | 1 +
net/sunrpc/xprtsock.c | 24 +++++++++++++++++++++---
2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 6f524a9..afb9e6a 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -257,6 +257,7 @@ void xprt_force_disconnect(struct rpc_xprt *xprt);
#define XPRT_CLOSE_WAIT (3)
#define XPRT_BOUND (4)
#define XPRT_BINDING (5)
+#define XPRT_CLOSING (6)

static inline void xprt_set_connected(struct rpc_xprt *xprt)
{
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 45cb1dc..607f233 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -758,7 +758,9 @@ static void xs_close(struct rpc_xprt *xprt)
sock_release(sock);
clear_close_wait:
smp_mb__before_clear_bit();
+ clear_bit(XPRT_CONNECTED, &xprt->state);
clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
+ clear_bit(XPRT_CLOSING, &xprt->state);
smp_mb__after_clear_bit();
}

@@ -1114,12 +1116,28 @@ static void xs_tcp_state_change(struct sock *sk)
}
spin_unlock_bh(&xprt->transport_lock);
break;
- case TCP_SYN_SENT:
- case TCP_SYN_RECV:
+ case TCP_FIN_WAIT1:
+ /* The client initiated a shutdown of the socket */
+ set_bit(XPRT_CLOSING, &xprt->state);
+ smp_mb__before_clear_bit();
+ clear_bit(XPRT_CONNECTED, &xprt->state);
+ smp_mb__after_clear_bit();
break;
case TCP_CLOSE_WAIT:
+ /* The server initiated a shutdown of the socket */
+ set_bit(XPRT_CLOSING, &xprt->state);
xprt_force_disconnect(xprt);
- default:
+ break;
+ case TCP_LAST_ACK:
+ smp_mb__before_clear_bit();
+ clear_bit(XPRT_CONNECTED, &xprt->state);
+ smp_mb__after_clear_bit();
+ break;
+ case TCP_CLOSE:
+ smp_mb__before_clear_bit();
+ clear_bit(XPRT_CLOSING, &xprt->state);
+ smp_mb__after_clear_bit();
+ /* Mark transport as closed and wake up all pending tasks */
xprt_disconnect(xprt);
}
out: