From d531c008d7d9713456abe3d265fc577bba2e1cef Mon Sep 17 00:00:00 2001 From: Kinglong Mee Date: Mon, 24 Mar 2014 11:59:46 +0800 Subject: [PATCH] NFSD/SUNRPC: Check rpc_xprt out of xs_setup_bc_tcp Besides checking rpc_xprt out of xs_setup_bc_tcp, increase it's reference (it's important). Signed-off-by: Kinglong Mee Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4callback.c | 19 ++++++++++++++++++- include/linux/sunrpc/xprt.h | 13 ++++++++++++- net/sunrpc/xprt.c | 12 ------------ net/sunrpc/xprtsock.c | 9 --------- 4 files changed, 30 insertions(+), 23 deletions(-) diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c index 7f05cd140de3..39c8ef875f91 100644 --- a/fs/nfsd/nfs4callback.c +++ b/fs/nfsd/nfs4callback.c @@ -32,6 +32,7 @@ */ #include +#include #include #include #include "nfsd.h" @@ -635,6 +636,22 @@ static struct rpc_cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc } } +static struct rpc_clnt *create_backchannel_client(struct rpc_create_args *args) +{ + struct rpc_xprt *xprt; + + if (args->protocol != XPRT_TRANSPORT_BC_TCP) + return rpc_create(args); + + xprt = args->bc_xprt->xpt_bc_xprt; + if (xprt) { + xprt_get(xprt); + return rpc_create_xprt(args, xprt); + } + + return rpc_create(args); +} + static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses) { struct rpc_timeout timeparms = { @@ -674,7 +691,7 @@ static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *c args.authflavor = ses->se_cb_sec.flavor; } /* Create RPC client */ - client = rpc_create(&args); + client = create_backchannel_client(&args); if (IS_ERR(client)) { dprintk("NFSD: couldn't create callback client: %ld\n", PTR_ERR(client)); diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 8097b9df6773..3e5efb2b236e 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -295,13 +295,24 @@ int xprt_adjust_timeout(struct rpc_rqst *req); void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); void xprt_release(struct rpc_task *task); -struct rpc_xprt * xprt_get(struct rpc_xprt *xprt); void xprt_put(struct rpc_xprt *xprt); struct rpc_xprt * xprt_alloc(struct net *net, size_t size, unsigned int num_prealloc, unsigned int max_req); void xprt_free(struct rpc_xprt *); +/** + * xprt_get - return a reference to an RPC transport. + * @xprt: pointer to the transport + * + */ +static inline struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) +{ + if (atomic_inc_not_zero(&xprt->count)) + return xprt; + return NULL; +} + static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p) { return p + xprt->tsh_size; diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index 7d4df99f761f..d173f79947c6 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -1383,15 +1383,3 @@ void xprt_put(struct rpc_xprt *xprt) if (atomic_dec_and_test(&xprt->count)) xprt_destroy(xprt); } - -/** - * xprt_get - return a reference to an RPC transport. - * @xprt: pointer to the transport - * - */ -struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) -{ - if (atomic_inc_not_zero(&xprt->count)) - return xprt; - return NULL; -} diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 63ae657f255b..1335239217cd 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -2923,15 +2923,6 @@ 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 - * transport; 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, xprt_tcp_slot_table_entries); if (IS_ERR(xprt)) -- 2.20.1