rpc: allow xprt_class->setup to return a preexisting xprt

This allows us to reuse the xprt associated with a server connection if
one has already been set up.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
J. Bruce Fields 2010-12-08 13:48:19 -05:00
parent 99de8ea962
commit f0418aa4b1
3 changed files with 13 additions and 9 deletions

View file

@ -321,6 +321,7 @@ void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
#define XPRT_CLOSING (6)
#define XPRT_CONNECTION_ABORT (7)
#define XPRT_CONNECTION_CLOSE (8)
#define XPRT_INITIALIZED (9)
static inline void xprt_set_connected(struct rpc_xprt *xprt)
{

View file

@ -1102,6 +1102,9 @@ struct rpc_xprt *xprt_create_transport(struct xprt_create *args)
-PTR_ERR(xprt));
return xprt;
}
if (test_and_set_bit(XPRT_INITIALIZED, &xprt->state))
/* ->setup returned a pre-initialized xprt: */
return xprt;
spin_lock_init(&xprt->transport_lock);
spin_lock_init(&xprt->reserve_lock);

View file

@ -2359,6 +2359,15 @@ static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
struct svc_sock *bc_sock;
struct rpc_xprt *ret;
if (args->bc_xprt->xpt_bc_xprt) {
/*
* This server connection already has a backchannel
* export; we can't create a new one, as we wouldn't be
* able to match replies based on xid any more. So,
* reuse the already-existing one:
*/
return args->bc_xprt->xpt_bc_xprt;
}
xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
if (IS_ERR(xprt))
return xprt;
@ -2396,15 +2405,6 @@ static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
xprt->address_strings[RPC_DISPLAY_PORT],
xprt->address_strings[RPC_DISPLAY_PROTO]);
/*
* The backchannel uses the same socket connection as the
* forechannel
*/
if (args->bc_xprt->xpt_bc_xprt) {
/* XXX: actually, want to catch this case... */
ret = ERR_PTR(-EINVAL);
goto out_err;
}
/*
* Once we've associated a backchannel xprt with a connection,
* we want to keep it around as long as long as the connection