nfsd4: support BIND_CONN_TO_SESSION

Basic xdr and processing for BIND_CONN_TO_SESSION.  This adds a
connection to the list of connections associated with a session.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 53 insertions, 6 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 3cf9900d5f32..956174f488a7 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -679,15 +679,12 @@ static int nfsd4_register_conn(struct nfsd4_conn *conn)
         return register_xpt_user(conn->cn_xprt, &conn->cn_xpt_user);
 }
 
-static __be32 nfsd4_new_conn(struct svc_rqst *rqstp, struct nfsd4_session *ses)
+static __be32 nfsd4_new_conn(struct svc_rqst *rqstp, struct nfsd4_session *ses, u32 dir)
 {
         struct nfsd4_conn *conn;
-        u32 flags = NFS4_CDFC4_FORE;
         int ret;
 
-        if (ses->se_flags & SESSION4_BACK_CHAN)
-                flags |= NFS4_CDFC4_BACK;
-        conn = alloc_conn(rqstp, flags);
+        conn = alloc_conn(rqstp, dir);
         if (!conn)
                 return nfserr_jukebox;
         nfsd4_hash_conn(conn, ses);
@@ -698,6 +695,17 @@ static __be32 nfsd4_new_conn(struct svc_rqst *rqstp, struct nfsd4_session *ses)
         return nfs_ok;
 }
 
+static __be32 nfsd4_new_conn_from_crses(struct svc_rqst *rqstp, struct nfsd4_session *ses)
+{
+        u32 dir = NFS4_CDFC4_FORE;
+
+        if (ses->se_flags & SESSION4_BACK_CHAN)
+                dir |= NFS4_CDFC4_BACK;
+
+        return nfsd4_new_conn(rqstp, ses, dir);
+}
+
+/* must be called under client_lock */
 static void nfsd4_del_conns(struct nfsd4_session *s)
 {
         struct nfs4_client *clp = s->se_client;
@@ -776,7 +784,7 @@ static struct nfsd4_session *alloc_init_session(struct svc_rqst *rqstp, struct n
         spin_unlock(&clp->cl_lock);
         spin_unlock(&client_lock);
 
-        status = nfsd4_new_conn(rqstp, new);
+        status = nfsd4_new_conn_from_crses(rqstp, new);
         /* whoops: benny points out, status is ignored! (err, or bogus) */
         if (status) {
                 free_session(&new->se_ref);
@@ -1597,6 +1605,45 @@ static bool nfsd4_last_compound_op(struct svc_rqst *rqstp)
         return argp->opcnt == resp->opcnt;
 }
 
+static __be32 nfsd4_map_bcts_dir(u32 *dir)
+{
+        switch (*dir) {
+        case NFS4_CDFC4_FORE:
+        case NFS4_CDFC4_BACK:
+                return nfs_ok;
+        case NFS4_CDFC4_FORE_OR_BOTH:
+        case NFS4_CDFC4_BACK_OR_BOTH:
+                *dir = NFS4_CDFC4_BOTH;
+                return nfs_ok;
+        };
+        return nfserr_inval;
+}
+
+__be32 nfsd4_bind_conn_to_session(struct svc_rqst *rqstp,
+                     struct nfsd4_compound_state *cstate,
+                     struct nfsd4_bind_conn_to_session *bcts)
+{
+        __be32 status;
+
+        if (!nfsd4_last_compound_op(rqstp))
+                return nfserr_not_only_op;
+        spin_lock(&client_lock);
+        cstate->session = find_in_sessionid_hashtbl(&bcts->sessionid);
+        /* Sorta weird: we only need the refcnt'ing because new_conn acquires
+         * client_lock iself: */
+        if (cstate->session) {
+                nfsd4_get_session(cstate->session);
+                atomic_inc(&cstate->session->se_client->cl_refcount);
+        }
+        spin_unlock(&client_lock);
+        if (!cstate->session)
+                return nfserr_badsession;
+
+        status = nfsd4_map_bcts_dir(&bcts->dir);
+        nfsd4_new_conn(rqstp, cstate->session, bcts->dir);
+        return nfs_ok;
+}
+
 static bool nfsd4_compound_in_session(struct nfsd4_session *session, struct nfs4_sessionid *sid)
 {
         if (!session)