NFSv4.1: Fix session initialisation races

Session initialisation is not complete until the lease manager
has run. We need to ensure that both nfs4_init_session and
nfs4_init_ds_session do so, and that they check for any resulting
errors in clp->cl_cons_state.

Only after this is done, can nfs4_ds_connect check the contents
of clp->cl_exchange_flags.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Andy Adamson <andros@netapp.com>

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 3c14468..25dde07 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -591,22 +591,6 @@ void nfs_mark_client_ready(struct nfs_client *clp, int state)
        wake_up_all(&nfs_client_active_wq);
 }
 
-/*
- * With sessions, the client is not marked ready until after a
- * successful EXCHANGE_ID and CREATE_SESSION.
- *
- * Map errors cl_cons_state errors to EPROTONOSUPPORT to indicate
- * other versions of NFS can be tried.
- */
-int nfs4_check_client_ready(struct nfs_client *clp)
-{
-       if (!nfs4_has_session(clp))
-               return 0;
-       if (clp->cl_cons_state < NFS_CS_READY)
-               return -EPROTONOSUPPORT;
-       return 0;
-}
-
 /*
  * Initialise the timeout values for a connection
  */

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 547f24f..5ea571e 100644 (file)
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -169,7 +169,6 @@ extern struct nfs_server *nfs_clone_server(struct nfs_server *,
                                           struct nfs_fattr *,
                                           rpc_authflavor_t);
 extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
-extern int nfs4_check_client_ready(struct nfs_client *clp);
 extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
                                             const struct sockaddr *ds_addr,
                                             int ds_addrlen, int ds_proto,
@@ -234,7 +233,7 @@ extern const u32 nfs41_maxwrite_overhead;
 extern struct rpc_procinfo nfs4_procedures[];
 #endif
 
-extern int nfs4_init_ds_session(struct nfs_client *clp);
+extern int nfs4_init_ds_session(struct nfs_client *, unsigned long);
 
 /* proc.c */
 void nfs_close_context(struct nfs_open_context *ctx, int is_sync);

diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index c610f84..a1fab8d 100644 (file)
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -203,28 +203,7 @@ nfs4_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds)
                goto out;
        }
 
-       if ((clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) != 0) {
-               if (!is_ds_client(clp)) {
-                       status = -ENODEV;
-                       goto out_put;
-               }
-               ds->ds_clp = clp;
-               dprintk("%s [existing] server=%s\n", __func__,
-                       ds->ds_remotestr);
-               goto out;
-       }
-
-       /*
-        * Do not set NFS_CS_CHECK_LEASE_TIME instead set the DS lease to
-        * be equal to the MDS lease. Renewal is scheduled in create_session.
-        */
-       spin_lock(&mds_srv->nfs_client->cl_lock);
-       clp->cl_lease_time = mds_srv->nfs_client->cl_lease_time;
-       spin_unlock(&mds_srv->nfs_client->cl_lock);
-       clp->cl_last_renewal = jiffies;
-
-       /* New nfs_client */
-       status = nfs4_init_ds_session(clp);
+       status = nfs4_init_ds_session(clp, mds_srv->nfs_client->cl_lease_time);
        if (status)
                goto out_put;
 

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 0d46fe4..c856298 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5603,53 +5603,78 @@ int nfs4_proc_destroy_session(struct nfs4_session *session)
        return status;
 }
 
+/*
+ * With sessions, the client is not marked ready until after a
+ * successful EXCHANGE_ID and CREATE_SESSION.
+ *
+ * Map errors cl_cons_state errors to EPROTONOSUPPORT to indicate
+ * other versions of NFS can be tried.
+ */
+static int nfs41_check_session_ready(struct nfs_client *clp)
+{
+       int ret;
+       
+       if (clp->cl_cons_state == NFS_CS_SESSION_INITING) {
+               ret = nfs4_client_recover_expired_lease(clp);
+               if (ret)
+                       return ret;
+       }
+       if (clp->cl_cons_state < NFS_CS_READY)
+               return -EPROTONOSUPPORT;
+       return 0;
+}
+
 int nfs4_init_session(struct nfs_server *server)
 {
        struct nfs_client *clp = server->nfs_client;
        struct nfs4_session *session;
        unsigned int rsize, wsize;
-       int ret;
 
        if (!nfs4_has_session(clp))
                return 0;
 
        session = clp->cl_session;
-       if (!test_and_clear_bit(NFS4_SESSION_INITING, &session->session_state))
-               return 0;
+       spin_lock(&clp->cl_lock);
+       if (test_and_clear_bit(NFS4_SESSION_INITING, &session->session_state)) {
 
-       rsize = server->rsize;
-       if (rsize == 0)
-               rsize = NFS_MAX_FILE_IO_SIZE;
-       wsize = server->wsize;
-       if (wsize == 0)
-               wsize = NFS_MAX_FILE_IO_SIZE;
+               rsize = server->rsize;
+               if (rsize == 0)
+                       rsize = NFS_MAX_FILE_IO_SIZE;
+               wsize = server->wsize;
+               if (wsize == 0)
+                       wsize = NFS_MAX_FILE_IO_SIZE;
 
-       session->fc_attrs.max_rqst_sz = wsize + nfs41_maxwrite_overhead;
-       session->fc_attrs.max_resp_sz = rsize + nfs41_maxread_overhead;
+               session->fc_attrs.max_rqst_sz = wsize + nfs41_maxwrite_overhead;
+               session->fc_attrs.max_resp_sz = rsize + nfs41_maxread_overhead;
+       }
+       spin_unlock(&clp->cl_lock);
 
-       ret = nfs4_recover_expired_lease(server);
-       if (!ret)
-               ret = nfs4_check_client_ready(clp);
-       return ret;
+       return nfs41_check_session_ready(clp);
 }
 
-int nfs4_init_ds_session(struct nfs_client *clp)
+int nfs4_init_ds_session(struct nfs_client *clp, unsigned long lease_time)
 {
        struct nfs4_session *session = clp->cl_session;
        int ret;
 
-       if (!test_and_clear_bit(NFS4_SESSION_INITING, &session->session_state))
-               return 0;
-
-       ret = nfs4_client_recover_expired_lease(clp);
-       if (!ret)
-               /* Test for the DS role */
-               if (!is_ds_client(clp))
-                       ret = -ENODEV;
-       if (!ret)
-               ret = nfs4_check_client_ready(clp);
-       return ret;
+       spin_lock(&clp->cl_lock);
+       if (test_and_clear_bit(NFS4_SESSION_INITING, &session->session_state)) {
+               /*
+                * Do not set NFS_CS_CHECK_LEASE_TIME instead set the
+                * DS lease to be equal to the MDS lease.
+                */
+               clp->cl_lease_time = lease_time;
+               clp->cl_last_renewal = jiffies;
+       }
+       spin_unlock(&clp->cl_lock);
 
+       ret = nfs41_check_session_ready(clp);
+       if (ret)
+               return ret;
+       /* Test for the DS role */
+       if (!is_ds_client(clp))
+               return -ENODEV;
+       return 0;
 }
 EXPORT_SYMBOL_GPL(nfs4_init_ds_session);