Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp

Conflicts:
	litmus/sched_cedf.c

1 files changed, 333 insertions, 125 deletions

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index e7340729af89..b3dc2b88b65b 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -48,6 +48,7 @@
 #include "iostat.h"
 #include "internal.h"
 #include "fscache.h"
+#include "pnfs.h"
 
 #define NFSDBG_FACILITY         NFSDBG_CLIENT
 
@@ -55,6 +56,35 @@ static DEFINE_SPINLOCK(nfs_client_lock);
 static LIST_HEAD(nfs_client_list);
 static LIST_HEAD(nfs_volume_list);
 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
+#ifdef CONFIG_NFS_V4
+static DEFINE_IDR(cb_ident_idr); /* Protected by nfs_client_lock */
+
+/*
+ * Get a unique NFSv4.0 callback identifier which will be used
+ * by the V4.0 callback service to lookup the nfs_client struct
+ */
+static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
+{
+        int ret = 0;
+
+        if (clp->rpc_ops->version != 4 || minorversion != 0)
+                return ret;
+retry:
+        if (!idr_pre_get(&cb_ident_idr, GFP_KERNEL))
+                return -ENOMEM;
+        spin_lock(&nfs_client_lock);
+        ret = idr_get_new(&cb_ident_idr, clp, &clp->cl_cb_ident);
+        spin_unlock(&nfs_client_lock);
+        if (ret == -EAGAIN)
+                goto retry;
+        return ret;
+}
+#endif /* CONFIG_NFS_V4 */
+
+/*
+ * Turn off NFSv4 uid/gid mapping when using AUTH_SYS
+ */
+static int nfs4_disable_idmapping = 0;
 
 /*
  * RPC cruft for NFS
@@ -143,7 +173,10 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
         clp->cl_proto = cl_init->proto;
 
 #ifdef CONFIG_NFS_V4
-        INIT_LIST_HEAD(&clp->cl_delegations);
+        err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
+        if (err)
+                goto error_cleanup;
+
         spin_lock_init(&clp->cl_lock);
         INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
         rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
@@ -155,7 +188,9 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
         cred = rpc_lookup_machine_cred();
         if (!IS_ERR(cred))
                 clp->cl_machine_cred = cred;
-
+#if defined(CONFIG_NFS_V4_1)
+        INIT_LIST_HEAD(&clp->cl_layouts);
+#endif
         nfs_fscache_get_client_cookie(clp);
 
         return clp;
@@ -167,21 +202,17 @@ error_0:
 }
 
 #ifdef CONFIG_NFS_V4
-/*
- * Clears/puts all minor version specific parts from an nfs_client struct
- * reverting it to minorversion 0.
- */
-static void nfs4_clear_client_minor_version(struct nfs_client *clp)
-{
 #ifdef CONFIG_NFS_V4_1
-        if (nfs4_has_session(clp)) {
+static void nfs4_shutdown_session(struct nfs_client *clp)
+{
+        if (nfs4_has_session(clp))
                 nfs4_destroy_session(clp->cl_session);
-                clp->cl_session = NULL;
-        }
-
-        clp->cl_mvops = nfs_v4_minor_ops[0];
-#endif /* CONFIG_NFS_V4_1 */
 }
+#else /* CONFIG_NFS_V4_1 */
+static void nfs4_shutdown_session(struct nfs_client *clp)
+{
+}
+#endif /* CONFIG_NFS_V4_1 */
 
 /*
  * Destroy the NFS4 callback service
@@ -196,17 +227,49 @@ static void nfs4_shutdown_client(struct nfs_client *clp)
 {
         if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
                 nfs4_kill_renewd(clp);
-        nfs4_clear_client_minor_version(clp);
+        nfs4_shutdown_session(clp);
         nfs4_destroy_callback(clp);
         if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
                 nfs_idmap_delete(clp);
 
         rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 }
+
+/* idr_remove_all is not needed as all id's are removed by nfs_put_client */
+void nfs_cleanup_cb_ident_idr(void)
+{
+        idr_destroy(&cb_ident_idr);
+}
+
+/* nfs_client_lock held */
+static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
+{
+        if (clp->cl_cb_ident)
+                idr_remove(&cb_ident_idr, clp->cl_cb_ident);
+}
+
+static void pnfs_init_server(struct nfs_server *server)
+{
+        rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
+}
+
 #else
 static void nfs4_shutdown_client(struct nfs_client *clp)
 {
 }
+
+void nfs_cleanup_cb_ident_idr(void)
+{
+}
+
+static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
+{
+}
+
+static void pnfs_init_server(struct nfs_server *server)
+{
+}
+
 #endif /* CONFIG_NFS_V4 */
 
 /*
@@ -227,6 +290,8 @@ static void nfs_free_client(struct nfs_client *clp)
         if (clp->cl_machine_cred != NULL)
                 put_rpccred(clp->cl_machine_cred);
 
+        nfs4_deviceid_purge_client(clp);
+
         kfree(clp->cl_hostname);
         kfree(clp);
 
@@ -245,6 +310,7 @@ void nfs_put_client(struct nfs_client *clp)
 
         if (atomic_dec_and_lock(&clp->cl_count, &nfs_client_lock)) {
                 list_del(&clp->cl_share_link);
+                nfs_cb_idr_remove_locked(clp);
                 spin_unlock(&nfs_client_lock);
 
                 BUG_ON(!list_empty(&clp->cl_superblocks));
@@ -252,6 +318,7 @@ void nfs_put_client(struct nfs_client *clp)
                 nfs_free_client(clp);
         }
 }
+EXPORT_SYMBOL_GPL(nfs_put_client);
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 /*
@@ -359,70 +426,28 @@ static int nfs_sockaddr_cmp(const struct sockaddr *sa1,
         return 0;
 }
 
-/*
- * Find a client by IP address and protocol version
- * - returns NULL if no such client
- */
-struct nfs_client *nfs_find_client(const struct sockaddr *addr, u32 nfsversion)
+/* Common match routine for v4.0 and v4.1 callback services */
+bool
+nfs4_cb_match_client(const struct sockaddr *addr, struct nfs_client *clp,
+                     u32 minorversion)
 {
-        struct nfs_client *clp;
+        struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 
-        spin_lock(&nfs_client_lock);
-        list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
-                struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
+        /* Don't match clients that failed to initialise */
+        if (!(clp->cl_cons_state == NFS_CS_READY ||
+            clp->cl_cons_state == NFS_CS_SESSION_INITING))
+                return false;
 
-                /* Don't match clients that failed to initialise properly */
-                if (!(clp->cl_cons_state == NFS_CS_READY ||
-                      clp->cl_cons_state == NFS_CS_SESSION_INITING))
-                        continue;
+        /* Match the version and minorversion */
+        if (clp->rpc_ops->version != 4 ||
+            clp->cl_minorversion != minorversion)
+                return false;
 
-                /* Different NFS versions cannot share the same nfs_client */
-                if (clp->rpc_ops->version != nfsversion)
-                        continue;
-
-                /* Match only the IP address, not the port number */
-                if (!nfs_sockaddr_match_ipaddr(addr, clap))
-                        continue;
+        /* Match only the IP address, not the port number */
+        if (!nfs_sockaddr_match_ipaddr(addr, clap))
+                return false;
 
-                atomic_inc(&clp->cl_count);
-                spin_unlock(&nfs_client_lock);
-                return clp;
-        }
-        spin_unlock(&nfs_client_lock);
-        return NULL;
-}
-
-/*
- * Find a client by IP address and protocol version
- * - returns NULL if no such client
- */
-struct nfs_client *nfs_find_client_next(struct nfs_client *clp)
-{
-        struct sockaddr *sap = (struct sockaddr *)&clp->cl_addr;
-        u32 nfsvers = clp->rpc_ops->version;
-
-        spin_lock(&nfs_client_lock);
-        list_for_each_entry_continue(clp, &nfs_client_list, cl_share_link) {
-                struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
-
-                /* Don't match clients that failed to initialise properly */
-                if (clp->cl_cons_state != NFS_CS_READY)
-                        continue;
-
-                /* Different NFS versions cannot share the same nfs_client */
-                if (clp->rpc_ops->version != nfsvers)
-                        continue;
-
-                /* Match only the IP address, not the port number */
-                if (!nfs_sockaddr_match_ipaddr(sap, clap))
-                        continue;
-
-                atomic_inc(&clp->cl_count);
-                spin_unlock(&nfs_client_lock);
-                return clp;
-        }
-        spin_unlock(&nfs_client_lock);
-        return NULL;
+        return true;
 }
 
 /*
@@ -463,7 +488,12 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
  * Look up a client by IP address and protocol version
  * - creates a new record if one doesn't yet exist
  */
-static struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
+static struct nfs_client *
+nfs_get_client(const struct nfs_client_initdata *cl_init,
+               const struct rpc_timeout *timeparms,
+               const char *ip_addr,
+               rpc_authflavor_t authflavour,
+               int noresvport)
 {
         struct nfs_client *clp, *new = NULL;
         int error;
@@ -494,6 +524,13 @@ install_client:
         clp = new;
         list_add(&clp->cl_share_link, &nfs_client_list);
         spin_unlock(&nfs_client_lock);
+
+        error = cl_init->rpc_ops->init_client(clp, timeparms, ip_addr,
+                                              authflavour, noresvport);
+        if (error < 0) {
+                nfs_put_client(clp);
+                return ERR_PTR(error);
+        }
         dprintk("--> nfs_get_client() = %p [new]\n", clp);
         return clp;
 
@@ -601,6 +638,7 @@ static int nfs_create_rpc_client(struct nfs_client *clp,
 {
         struct rpc_clnt         *clnt = NULL;
         struct rpc_create_args args = {
+                .net            = &init_net,
                 .protocol       = clp->cl_proto,
                 .address        = (struct sockaddr *)&clp->cl_addr,
                 .addrsize       = clp->cl_addrlen,
@@ -635,7 +673,8 @@ static int nfs_create_rpc_client(struct nfs_client *clp,
  */
 static void nfs_destroy_server(struct nfs_server *server)
 {
-        if (!(server->flags & NFS_MOUNT_NONLM))
+        if (!(server->flags & NFS_MOUNT_LOCAL_FLOCK) ||
+                        !(server->flags & NFS_MOUNT_LOCAL_FCNTL))
                 nlmclnt_done(server->nlm_host);
 }
 
@@ -657,7 +696,8 @@ static int nfs_start_lockd(struct nfs_server *server)
 
         if (nlm_init.nfs_version > 3)
                 return 0;
-        if (server->flags & NFS_MOUNT_NONLM)
+        if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
+                        (server->flags & NFS_MOUNT_LOCAL_FCNTL))
                 return 0;
 
         switch (clp->cl_proto) {
@@ -746,9 +786,9 @@ static int nfs_init_server_rpcclient(struct nfs_server *server,
 /*
  * Initialise an NFS2 or NFS3 client
  */
-static int nfs_init_client(struct nfs_client *clp,
-                           const struct rpc_timeout *timeparms,
-                           const struct nfs_parsed_mount_data *data)
+int nfs_init_client(struct nfs_client *clp, const struct rpc_timeout *timeparms,
+                    const char *ip_addr, rpc_authflavor_t authflavour,
+                    int noresvport)
 {
         int error;
 
@@ -763,7 +803,7 @@ static int nfs_init_client(struct nfs_client *clp,
          * - RFC 2623, sec 2.3.2
          */
         error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX,
-                                      0, data->flags & NFS_MOUNT_NORESVPORT);
+                                      0, noresvport);
         if (error < 0)
                 goto error;
         nfs_mark_client_ready(clp, NFS_CS_READY);
@@ -799,19 +839,17 @@ static int nfs_init_server(struct nfs_server *server,
                 cl_init.rpc_ops = &nfs_v3_clientops;
 #endif
 
+        nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
+                        data->timeo, data->retrans);
+
         /* Allocate or find a client reference we can use */
-        clp = nfs_get_client(&cl_init);
+        clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX,
+                             data->flags & NFS_MOUNT_NORESVPORT);
         if (IS_ERR(clp)) {
                 dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
                 return PTR_ERR(clp);
         }
 
-        nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
-                        data->timeo, data->retrans);
-        error = nfs_init_client(clp, &timeparms, data);
-        if (error < 0)
-                goto error;
-
         server->nfs_client = clp;
 
         /* Initialise the client representation from the mount data */
@@ -898,11 +936,13 @@ static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo *
         if (server->wsize > NFS_MAX_FILE_IO_SIZE)
                 server->wsize = NFS_MAX_FILE_IO_SIZE;
         server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+        set_pnfs_layoutdriver(server, fsinfo->layouttype);
+
         server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
 
         server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
-        if (server->dtsize > PAGE_CACHE_SIZE)
-                server->dtsize = PAGE_CACHE_SIZE;
+        if (server->dtsize > PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES)
+                server->dtsize = PAGE_CACHE_SIZE * NFS_MAX_READDIR_PAGES;
         if (server->dtsize > server->rsize)
                 server->dtsize = server->rsize;
 
@@ -913,6 +953,8 @@ static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo *
 
         server->maxfilesize = fsinfo->maxfilesize;
 
+        server->time_delta = fsinfo->time_delta;
+
         /* We're airborne Set socket buffersize */
         rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
 }
@@ -935,6 +977,7 @@ static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, str
         }
 
         fsinfo.fattr = fattr;
+        fsinfo.layouttype = 0;
         error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
         if (error < 0)
                 goto out_error;
@@ -976,6 +1019,32 @@ static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_serve
         target->options = source->options;
 }
 
+static void nfs_server_insert_lists(struct nfs_server *server)
+{
+        struct nfs_client *clp = server->nfs_client;
+
+        spin_lock(&nfs_client_lock);
+        list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
+        list_add_tail(&server->master_link, &nfs_volume_list);
+        clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
+        spin_unlock(&nfs_client_lock);
+
+}
+
+static void nfs_server_remove_lists(struct nfs_server *server)
+{
+        struct nfs_client *clp = server->nfs_client;
+
+        spin_lock(&nfs_client_lock);
+        list_del_rcu(&server->client_link);
+        if (clp && list_empty(&clp->cl_superblocks))
+                set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
+        list_del(&server->master_link);
+        spin_unlock(&nfs_client_lock);
+
+        synchronize_rcu();
+}
+
 /*
  * Allocate and initialise a server record
  */
@@ -992,6 +1061,7 @@ static struct nfs_server *nfs_alloc_server(void)
         /* Zero out the NFS state stuff */
         INIT_LIST_HEAD(&server->client_link);
         INIT_LIST_HEAD(&server->master_link);
+        INIT_LIST_HEAD(&server->delegations);
 
         atomic_set(&server->active, 0);
 
@@ -1007,6 +1077,8 @@ static struct nfs_server *nfs_alloc_server(void)
                 return NULL;
         }
 
+        pnfs_init_server(server);
+
         return server;
 }
 
@@ -1017,10 +1089,8 @@ void nfs_free_server(struct nfs_server *server)
 {
         dprintk("--> nfs_free_server()\n");
 
-        spin_lock(&nfs_client_lock);
-        list_del(&server->client_link);
-        list_del(&server->master_link);
-        spin_unlock(&nfs_client_lock);
+        nfs_server_remove_lists(server);
+        unset_pnfs_layoutdriver(server);
 
         if (server->destroy != NULL)
                 server->destroy(server);
@@ -1095,11 +1165,7 @@ struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
                 (unsigned long long) server->fsid.major,
                 (unsigned long long) server->fsid.minor);
 
-        spin_lock(&nfs_client_lock);
-        list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
-        list_add_tail(&server->master_link, &nfs_volume_list);
-        spin_unlock(&nfs_client_lock);
-
+        nfs_server_insert_lists(server);
         server->mount_time = jiffies;
         nfs_free_fattr(fattr);
         return server;
@@ -1112,6 +1178,96 @@ error:
 
 #ifdef CONFIG_NFS_V4
 /*
+ * NFSv4.0 callback thread helper
+ *
+ * Find a client by IP address, protocol version, and minorversion
+ *
+ * Called from the pg_authenticate method. The callback identifier
+ * is not used as it has not been decoded.
+ *
+ * Returns NULL if no such client
+ */
+struct nfs_client *
+nfs4_find_client_no_ident(const struct sockaddr *addr)
+{
+        struct nfs_client *clp;
+
+        spin_lock(&nfs_client_lock);
+        list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
+                if (nfs4_cb_match_client(addr, clp, 0) == false)
+                        continue;
+                atomic_inc(&clp->cl_count);
+                spin_unlock(&nfs_client_lock);
+                return clp;
+        }
+        spin_unlock(&nfs_client_lock);
+        return NULL;
+}
+
+/*
+ * NFSv4.0 callback thread helper
+ *
+ * Find a client by callback identifier
+ */
+struct nfs_client *
+nfs4_find_client_ident(int cb_ident)
+{
+        struct nfs_client *clp;
+
+        spin_lock(&nfs_client_lock);
+        clp = idr_find(&cb_ident_idr, cb_ident);
+        if (clp)
+                atomic_inc(&clp->cl_count);
+        spin_unlock(&nfs_client_lock);
+        return clp;
+}
+
+#if defined(CONFIG_NFS_V4_1)
+/*
+ * NFSv4.1 callback thread helper
+ * For CB_COMPOUND calls, find a client by IP address, protocol version,
+ * minorversion, and sessionID
+ *
+ * Returns NULL if no such client
+ */
+struct nfs_client *
+nfs4_find_client_sessionid(const struct sockaddr *addr,
+                           struct nfs4_sessionid *sid)
+{
+        struct nfs_client *clp;
+
+        spin_lock(&nfs_client_lock);
+        list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
+                if (nfs4_cb_match_client(addr, clp, 1) == false)
+                        continue;
+
+                if (!nfs4_has_session(clp))
+                        continue;
+
+                /* Match sessionid*/
+                if (memcmp(clp->cl_session->sess_id.data,
+                    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
+                        continue;
+
+                atomic_inc(&clp->cl_count);
+                spin_unlock(&nfs_client_lock);
+                return clp;
+        }
+        spin_unlock(&nfs_client_lock);
+        return NULL;
+}
+
+#else /* CONFIG_NFS_V4_1 */
+
+struct nfs_client *
+nfs4_find_client_sessionid(const struct sockaddr *addr,
+                           struct nfs4_sessionid *sid)
+{
+        return NULL;
+}
+#endif /* CONFIG_NFS_V4_1 */
+
+/*
  * Initialize the NFS4 callback service
  */
 static int nfs4_init_callback(struct nfs_client *clp)
@@ -1173,11 +1329,11 @@ static int nfs4_init_client_minor_version(struct nfs_client *clp)
 /*
  * Initialise an NFS4 client record
  */
-static int nfs4_init_client(struct nfs_client *clp,
-                const struct rpc_timeout *timeparms,
-                const char *ip_addr,
-                rpc_authflavor_t authflavour,
-                int flags)
+int nfs4_init_client(struct nfs_client *clp,
+                     const struct rpc_timeout *timeparms,
+                     const char *ip_addr,
+                     rpc_authflavor_t authflavour,
+                     int noresvport)
 {
         int error;
 
@@ -1191,7 +1347,7 @@ static int nfs4_init_client(struct nfs_client *clp,
         clp->rpc_ops = &nfs_v4_clientops;
 
         error = nfs_create_rpc_client(clp, timeparms, authflavour,
-                                      1, flags & NFS_MOUNT_NORESVPORT);
+                                      1, noresvport);
         if (error < 0)
                 goto error;
         strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
@@ -1244,27 +1400,71 @@ static int nfs4_set_client(struct nfs_server *server,
         dprintk("--> nfs4_set_client()\n");
 
         /* Allocate or find a client reference we can use */
-        clp = nfs_get_client(&cl_init);
+        clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour,
+                             server->flags & NFS_MOUNT_NORESVPORT);
         if (IS_ERR(clp)) {
                 error = PTR_ERR(clp);
                 goto error;
         }
-        error = nfs4_init_client(clp, timeparms, ip_addr, authflavour,
-                                        server->flags);
-        if (error < 0)
-                goto error_put;
+
+        /*
+         * Query for the lease time on clientid setup or renewal
+         *
+         * Note that this will be set on nfs_clients that were created
+         * only for the DS role and did not set this bit, but now will
+         * serve a dual role.
+         */
+        set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 
         server->nfs_client = clp;
         dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
         return 0;
-
-error_put:
-        nfs_put_client(clp);
 error:
         dprintk("<-- nfs4_set_client() = xerror %d\n", error);
         return error;
 }
 
+/*
+ * Set up a pNFS Data Server client.
+ *
+ * Return any existing nfs_client that matches server address,port,version
+ * and minorversion.
+ *
+ * For a new nfs_client, use a soft mount (default), a low retrans and a
+ * low timeout interval so that if a connection is lost, we retry through
+ * the MDS.
+ */
+struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
+                const struct sockaddr *ds_addr,
+                int ds_addrlen, int ds_proto)
+{
+        struct nfs_client_initdata cl_init = {
+                .addr = ds_addr,
+                .addrlen = ds_addrlen,
+                .rpc_ops = &nfs_v4_clientops,
+                .proto = ds_proto,
+                .minorversion = mds_clp->cl_minorversion,
+        };
+        struct rpc_timeout ds_timeout = {
+                .to_initval = 15 * HZ,
+                .to_maxval = 15 * HZ,
+                .to_retries = 1,
+                .to_exponential = 1,
+        };
+        struct nfs_client *clp;
+
+        /*
+         * Set an authflavor equual to the MDS value. Use the MDS nfs_client
+         * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
+         * (section 13.1 RFC 5661).
+         */
+        clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
+                             mds_clp->cl_rpcclient->cl_auth->au_flavor, 0);
+
+        dprintk("<-- %s %p\n", __func__, clp);
+        return clp;
+}
+EXPORT_SYMBOL(nfs4_set_ds_client);
 
 /*
  * Session has been established, and the client marked ready.
@@ -1301,6 +1501,10 @@ static int nfs4_server_common_setup(struct nfs_server *server,
         BUG_ON(!server->nfs_client->rpc_ops);
         BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
 
+        /* data servers support only a subset of NFSv4.1 */
+        if (is_ds_only_client(server->nfs_client))
+                return -EPROTONOSUPPORT;
+
         fattr = nfs_alloc_fattr();
         if (fattr == NULL)
                 return -ENOMEM;
@@ -1329,11 +1533,7 @@ static int nfs4_server_common_setup(struct nfs_server *server,
         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
                 server->namelen = NFS4_MAXNAMLEN;
 
-        spin_lock(&nfs_client_lock);
-        list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
-        list_add_tail(&server->master_link, &nfs_volume_list);
-        spin_unlock(&nfs_client_lock);
-
+        nfs_server_insert_lists(server);
         server->mount_time = jiffies;
 out:
         nfs_free_fattr(fattr);
@@ -1356,8 +1556,9 @@ static int nfs4_init_server(struct nfs_server *server,
 
         /* Initialise the client representation from the mount data */
         server->flags = data->flags;
-        server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|
-                NFS_CAP_POSIX_LOCK;
+        server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|NFS_CAP_POSIX_LOCK;
+        if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
+                        server->caps |= NFS_CAP_READDIRPLUS;
         server->options = data->options;
 
         /* Get a client record */
@@ -1373,6 +1574,13 @@ static int nfs4_init_server(struct nfs_server *server,
         if (error < 0)
                 goto error;
 
+        /*
+         * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
+         * authentication.
+         */
+        if (nfs4_disable_idmapping && data->auth_flavors[0] == RPC_AUTH_UNIX)
+                server->caps |= NFS_CAP_UIDGID_NOMAP;
+
         if (data->rsize)
                 server->rsize = nfs_block_size(data->rsize, NULL);
         if (data->wsize)
@@ -1537,11 +1745,7 @@ struct nfs_server *nfs_clone_server(struct nfs_server *source,
         if (error < 0)
                 goto out_free_server;
 
-        spin_lock(&nfs_client_lock);
-        list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
-        list_add_tail(&server->master_link, &nfs_volume_list);
-        spin_unlock(&nfs_client_lock);
-
+        nfs_server_insert_lists(server);
         server->mount_time = jiffies;
 
         nfs_free_fattr(fattr_fsinfo);
@@ -1794,3 +1998,7 @@ void nfs_fs_proc_exit(void)
 }
 
 #endif /* CONFIG_PROC_FS */
+
+module_param(nfs4_disable_idmapping, bool, 0644);
+MODULE_PARM_DESC(nfs4_disable_idmapping,
+                "Turn off NFSv4 idmapping when using 'sec=sys'");