NFSv4.1: fix handling of backchannel binding in BIND_CONN_TO_SESSION

commit dff58530c4ca8ce7ee5a74db431c6e35362cf682 upstream.

Currently, if the client sends BIND_CONN_TO_SESSION with
NFS4_CDFC4_FORE_OR_BOTH but only gets NFS4_CDFS4_FORE back it ignores
that it wasn't able to enable a backchannel.

To make sure, the client sends BIND_CONN_TO_SESSION as the first
operation on the connections (ie., no other session compounds haven't
been sent before), and if the client's request to bind the backchannel
is not satisfied, then reset the connection and retry.

Cc: stable@vger.kernel.org
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 69b7ab7a58157f4d7b3e7787d4d2b1dc9750ff7d..1b1e21bcb9940c7036d43763c7b4b37ce08525d4 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7893,6 +7893,7 @@ static void
 nfs4_bind_one_conn_to_session_done(struct rpc_task *task, void *calldata)
 {
        struct nfs41_bind_conn_to_session_args *args = task->tk_msg.rpc_argp;
+       struct nfs41_bind_conn_to_session_res *res = task->tk_msg.rpc_resp;
        struct nfs_client *clp = args->client;
 
        switch (task->tk_status) {
@@ -7901,6 +7902,12 @@ nfs4_bind_one_conn_to_session_done(struct rpc_task *task, void *calldata)
                nfs4_schedule_session_recovery(clp->cl_session,
                                task->tk_status);
        }
+       if (args->dir == NFS4_CDFC4_FORE_OR_BOTH &&
+                       res->dir != NFS4_CDFS4_BOTH) {
+               rpc_task_close_connection(task);
+               if (args->retries++ < MAX_BIND_CONN_TO_SESSION_RETRIES)
+                       rpc_restart_call(task);
+       }
 }
 
 static const struct rpc_call_ops nfs4_bind_one_conn_to_session_ops = {
@@ -7923,6 +7930,7 @@ int nfs4_proc_bind_one_conn_to_session(struct rpc_clnt *clnt,
        struct nfs41_bind_conn_to_session_args args = {
                .client = clp,
                .dir = NFS4_CDFC4_FORE_OR_BOTH,
+               .retries = 0,
        };
        struct nfs41_bind_conn_to_session_res res;
        struct rpc_message msg = {

diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 94c77ed55ce1b4177f9382121769ac5eb4ea1f3a..faa150b4e85d96c9e0b9302bb5194e9dc23ed6c6 100644 (file)
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1307,11 +1307,13 @@ struct nfs41_impl_id {
        struct nfstime4                 date;
 };
 
+#define MAX_BIND_CONN_TO_SESSION_RETRIES 3
 struct nfs41_bind_conn_to_session_args {
        struct nfs_client               *client;
        struct nfs4_sessionid           sessionid;
        u32                             dir;
        bool                            use_conn_in_rdma_mode;
+       int                             retries;
 };
 
 struct nfs41_bind_conn_to_session_res {

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index ca7e108248e211208c0d2317b3b28cbd8394660f..cc20a0816830388c7542025aa8b9c209bfcf8944 100644 (file)
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -236,4 +236,9 @@ static inline int rpc_reply_expected(struct rpc_task *task)
                (task->tk_msg.rpc_proc->p_decode != NULL);
 }
 
+static inline void rpc_task_close_connection(struct rpc_task *task)
+{
+       if (task->tk_xprt)
+               xprt_force_disconnect(task->tk_xprt);
+}
 #endif /* _LINUX_SUNRPC_CLNT_H */