2 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
3 * Written by David Howells (dhowells@redhat.com)
5 #include <linux/module.h>
6 #include <linux/nfs_fs.h>
7 #include <linux/nfs_idmap.h>
8 #include <linux/nfs_mount.h>
9 #include <linux/sunrpc/addr.h>
10 #include <linux/sunrpc/auth.h>
11 #include <linux/sunrpc/xprt.h>
12 #include <linux/sunrpc/bc_xprt.h>
15 #include "delegation.h"
16 #include "nfs4session.h"
20 #define NFSDBG_FACILITY NFSDBG_CLIENT
23 * Get a unique NFSv4.0 callback identifier which will be used
24 * by the V4.0 callback service to lookup the nfs_client struct
26 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
29 struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
31 if (clp->rpc_ops->version != 4 || minorversion != 0)
33 idr_preload(GFP_KERNEL);
34 spin_lock(&nn->nfs_client_lock);
35 ret = idr_alloc(&nn->cb_ident_idr, clp, 0, 0, GFP_NOWAIT);
37 clp->cl_cb_ident = ret;
38 spin_unlock(&nn->nfs_client_lock);
40 return ret < 0 ? ret : 0;
43 #ifdef CONFIG_NFS_V4_1
44 static void nfs4_shutdown_session(struct nfs_client *clp)
46 if (nfs4_has_session(clp)) {
47 nfs4_destroy_session(clp->cl_session);
48 nfs4_destroy_clientid(clp);
52 #else /* CONFIG_NFS_V4_1 */
53 static void nfs4_shutdown_session(struct nfs_client *clp)
56 #endif /* CONFIG_NFS_V4_1 */
58 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
61 struct nfs_client *clp = nfs_alloc_client(cl_init);
65 err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
69 spin_lock_init(&clp->cl_lock);
70 INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
71 rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
72 clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
73 clp->cl_minorversion = cl_init->minorversion;
74 clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
83 * Destroy the NFS4 callback service
85 static void nfs4_destroy_callback(struct nfs_client *clp)
87 if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
88 nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
91 static void nfs4_shutdown_client(struct nfs_client *clp)
93 if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
94 nfs4_kill_renewd(clp);
95 nfs4_shutdown_session(clp);
96 nfs4_destroy_callback(clp);
97 if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
98 nfs_idmap_delete(clp);
100 rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
101 kfree(clp->cl_serverowner);
102 kfree(clp->cl_serverscope);
103 kfree(clp->cl_implid);
106 void nfs4_free_client(struct nfs_client *clp)
108 nfs4_shutdown_client(clp);
109 nfs_free_client(clp);
113 * Initialize the NFS4 callback service
115 static int nfs4_init_callback(struct nfs_client *clp)
119 if (clp->rpc_ops->version == 4) {
120 struct rpc_xprt *xprt;
122 xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
124 if (nfs4_has_session(clp)) {
125 error = xprt_setup_backchannel(xprt,
126 NFS41_BC_MIN_CALLBACKS);
131 error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
133 dprintk("%s: failed to start callback. Error = %d\n",
137 __set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
143 * Initialize the minor version specific parts of an NFS4 client record
145 static int nfs4_init_client_minor_version(struct nfs_client *clp)
147 #if defined(CONFIG_NFS_V4_1)
148 if (clp->cl_mvops->minor_version) {
149 struct nfs4_session *session = NULL;
151 * Create the session and mark it expired.
152 * When a SEQUENCE operation encounters the expired session
153 * it will do session recovery to initialize it.
155 session = nfs4_alloc_session(clp);
159 clp->cl_session = session;
161 * The create session reply races with the server back
162 * channel probe. Mark the client NFS_CS_SESSION_INITING
163 * so that the client back channel can find the
166 nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
168 #endif /* CONFIG_NFS_V4_1 */
170 return nfs4_init_callback(clp);
174 * nfs4_init_client - Initialise an NFS4 client record
176 * @clp: nfs_client to initialise
177 * @timeparms: timeout parameters for underlying RPC transport
178 * @ip_addr: callback IP address in presentation format
179 * @authflavor: authentication flavor for underlying RPC transport
181 * Returns pointer to an NFS client, or an ERR_PTR value.
183 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
184 const struct rpc_timeout *timeparms,
186 rpc_authflavor_t authflavour)
188 char buf[INET6_ADDRSTRLEN + 1];
189 struct nfs_client *old;
192 if (clp->cl_cons_state == NFS_CS_READY) {
193 /* the client is initialised already */
194 dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
198 /* Check NFS protocol revision and initialize RPC op vector */
199 clp->rpc_ops = &nfs_v4_clientops;
201 __set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
202 error = nfs_create_rpc_client(clp, timeparms, authflavour);
206 /* If no clientaddr= option was specified, find a usable cb address */
207 if (ip_addr == NULL) {
208 struct sockaddr_storage cb_addr;
209 struct sockaddr *sap = (struct sockaddr *)&cb_addr;
211 error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
214 error = rpc_ntop(sap, buf, sizeof(buf));
217 ip_addr = (const char *)buf;
219 strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
221 error = nfs_idmap_new(clp);
223 dprintk("%s: failed to create idmapper. Error = %d\n",
227 __set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
229 error = nfs4_init_client_minor_version(clp);
233 if (!nfs4_has_session(clp))
234 nfs_mark_client_ready(clp, NFS_CS_READY);
236 error = nfs4_discover_server_trunking(clp, &old);
241 clp->cl_preserve_clid = true;
248 nfs_mark_client_ready(clp, error);
250 dprintk("<-- nfs4_init_client() = xerror %d\n", error);
251 return ERR_PTR(error);
255 * SETCLIENTID just did a callback update with the callback ident in
256 * "drop," but server trunking discovery claims "drop" and "keep" are
257 * actually the same server. Swap the callback IDs so that "keep"
258 * will continue to use the callback ident the server now knows about,
259 * and so that "keep"'s original callback ident is destroyed when
262 static void nfs4_swap_callback_idents(struct nfs_client *keep,
263 struct nfs_client *drop)
265 struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
266 unsigned int save = keep->cl_cb_ident;
268 if (keep->cl_cb_ident == drop->cl_cb_ident)
271 dprintk("%s: keeping callback ident %u and dropping ident %u\n",
272 __func__, keep->cl_cb_ident, drop->cl_cb_ident);
274 spin_lock(&nn->nfs_client_lock);
276 idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
277 keep->cl_cb_ident = drop->cl_cb_ident;
279 idr_replace(&nn->cb_ident_idr, drop, save);
280 drop->cl_cb_ident = save;
282 spin_unlock(&nn->nfs_client_lock);
286 * nfs40_walk_client_list - Find server that recognizes a client ID
288 * @new: nfs_client with client ID to test
289 * @result: OUT: found nfs_client, or new
290 * @cred: credential to use for trunking test
292 * Returns zero, a negative errno, or a negative NFS4ERR status.
293 * If zero is returned, an nfs_client pointer is planted in "result."
295 * NB: nfs40_walk_client_list() relies on the new nfs_client being
296 * the last nfs_client on the list.
298 int nfs40_walk_client_list(struct nfs_client *new,
299 struct nfs_client **result,
300 struct rpc_cred *cred)
302 struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
303 struct nfs_client *pos, *n, *prev = NULL;
304 struct nfs4_setclientid_res clid = {
305 .clientid = new->cl_clientid,
306 .confirm = new->cl_confirm,
308 int status = -NFS4ERR_STALE_CLIENTID;
310 spin_lock(&nn->nfs_client_lock);
311 list_for_each_entry_safe(pos, n, &nn->nfs_client_list, cl_share_link) {
312 /* If "pos" isn't marked ready, we can't trust the
313 * remaining fields in "pos" */
314 if (pos->cl_cons_state < NFS_CS_READY)
317 if (pos->rpc_ops != new->rpc_ops)
320 if (pos->cl_proto != new->cl_proto)
323 if (pos->cl_minorversion != new->cl_minorversion)
326 if (pos->cl_clientid != new->cl_clientid)
329 atomic_inc(&pos->cl_count);
330 spin_unlock(&nn->nfs_client_lock);
333 nfs_put_client(prev);
336 status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
338 case -NFS4ERR_STALE_CLIENTID:
341 nfs4_swap_callback_idents(pos, new);
345 dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
346 __func__, pos, atomic_read(&pos->cl_count));
351 spin_lock(&nn->nfs_client_lock);
353 spin_unlock(&nn->nfs_client_lock);
355 /* No match found. The server lost our clientid */
358 nfs_put_client(prev);
359 dprintk("NFS: <-- %s status = %d\n", __func__, status);
363 #ifdef CONFIG_NFS_V4_1
365 * Returns true if the client IDs match
367 static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
369 if (a->cl_clientid != b->cl_clientid) {
370 dprintk("NFS: --> %s client ID %llx does not match %llx\n",
371 __func__, a->cl_clientid, b->cl_clientid);
374 dprintk("NFS: --> %s client ID %llx matches %llx\n",
375 __func__, a->cl_clientid, b->cl_clientid);
380 * Returns true if the server owners match
383 nfs4_match_serverowners(struct nfs_client *a, struct nfs_client *b)
385 struct nfs41_server_owner *o1 = a->cl_serverowner;
386 struct nfs41_server_owner *o2 = b->cl_serverowner;
388 if (o1->minor_id != o2->minor_id) {
389 dprintk("NFS: --> %s server owner minor IDs do not match\n",
394 if (o1->major_id_sz != o2->major_id_sz)
395 goto out_major_mismatch;
396 if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
397 goto out_major_mismatch;
399 dprintk("NFS: --> %s server owners match\n", __func__);
403 dprintk("NFS: --> %s server owner major IDs do not match\n",
409 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
411 * @new: nfs_client with client ID to test
412 * @result: OUT: found nfs_client, or new
413 * @cred: credential to use for trunking test
415 * Returns zero, a negative errno, or a negative NFS4ERR status.
416 * If zero is returned, an nfs_client pointer is planted in "result."
418 * NB: nfs41_walk_client_list() relies on the new nfs_client being
419 * the last nfs_client on the list.
421 int nfs41_walk_client_list(struct nfs_client *new,
422 struct nfs_client **result,
423 struct rpc_cred *cred)
425 struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
426 struct nfs_client *pos, *n, *prev = NULL;
427 int status = -NFS4ERR_STALE_CLIENTID;
429 spin_lock(&nn->nfs_client_lock);
430 list_for_each_entry_safe(pos, n, &nn->nfs_client_list, cl_share_link) {
431 /* If "pos" isn't marked ready, we can't trust the
432 * remaining fields in "pos", especially the client
433 * ID and serverowner fields. Wait for CREATE_SESSION
435 if (pos->cl_cons_state < NFS_CS_READY) {
436 atomic_inc(&pos->cl_count);
437 spin_unlock(&nn->nfs_client_lock);
440 nfs_put_client(prev);
443 nfs4_schedule_lease_recovery(pos);
444 status = nfs_wait_client_init_complete(pos);
447 spin_lock(&nn->nfs_client_lock);
450 status = pos->cl_cons_state;
451 spin_lock(&nn->nfs_client_lock);
456 if (pos->rpc_ops != new->rpc_ops)
459 if (pos->cl_proto != new->cl_proto)
462 if (pos->cl_minorversion != new->cl_minorversion)
465 if (!nfs4_match_clientids(pos, new))
468 if (!nfs4_match_serverowners(pos, new))
471 atomic_inc(&pos->cl_count);
472 spin_unlock(&nn->nfs_client_lock);
473 dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
474 __func__, pos, atomic_read(&pos->cl_count));
480 /* No matching nfs_client found. */
481 spin_unlock(&nn->nfs_client_lock);
482 dprintk("NFS: <-- %s status = %d\n", __func__, status);
485 #endif /* CONFIG_NFS_V4_1 */
487 static void nfs4_destroy_server(struct nfs_server *server)
489 nfs_server_return_all_delegations(server);
490 unset_pnfs_layoutdriver(server);
491 nfs4_purge_state_owners(server);
495 * NFSv4.0 callback thread helper
497 * Find a client by callback identifier
500 nfs4_find_client_ident(struct net *net, int cb_ident)
502 struct nfs_client *clp;
503 struct nfs_net *nn = net_generic(net, nfs_net_id);
505 spin_lock(&nn->nfs_client_lock);
506 clp = idr_find(&nn->cb_ident_idr, cb_ident);
508 atomic_inc(&clp->cl_count);
509 spin_unlock(&nn->nfs_client_lock);
513 #if defined(CONFIG_NFS_V4_1)
514 /* Common match routine for v4.0 and v4.1 callback services */
515 static bool nfs4_cb_match_client(const struct sockaddr *addr,
516 struct nfs_client *clp, u32 minorversion)
518 struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
520 /* Don't match clients that failed to initialise */
521 if (!(clp->cl_cons_state == NFS_CS_READY ||
522 clp->cl_cons_state == NFS_CS_SESSION_INITING))
527 /* Match the version and minorversion */
528 if (clp->rpc_ops->version != 4 ||
529 clp->cl_minorversion != minorversion)
532 /* Match only the IP address, not the port number */
533 if (!nfs_sockaddr_match_ipaddr(addr, clap))
540 * NFSv4.1 callback thread helper
541 * For CB_COMPOUND calls, find a client by IP address, protocol version,
542 * minorversion, and sessionID
544 * Returns NULL if no such client
547 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
548 struct nfs4_sessionid *sid)
550 struct nfs_client *clp;
551 struct nfs_net *nn = net_generic(net, nfs_net_id);
553 spin_lock(&nn->nfs_client_lock);
554 list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
555 if (nfs4_cb_match_client(addr, clp, 1) == false)
558 if (!nfs4_has_session(clp))
562 if (memcmp(clp->cl_session->sess_id.data,
563 sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
566 atomic_inc(&clp->cl_count);
567 spin_unlock(&nn->nfs_client_lock);
570 spin_unlock(&nn->nfs_client_lock);
574 #else /* CONFIG_NFS_V4_1 */
577 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
578 struct nfs4_sessionid *sid)
582 #endif /* CONFIG_NFS_V4_1 */
585 * Set up an NFS4 client
587 static int nfs4_set_client(struct nfs_server *server,
588 const char *hostname,
589 const struct sockaddr *addr,
590 const size_t addrlen,
592 rpc_authflavor_t authflavour,
593 int proto, const struct rpc_timeout *timeparms,
594 u32 minorversion, struct net *net)
596 struct nfs_client_initdata cl_init = {
597 .hostname = hostname,
602 .minorversion = minorversion,
605 struct nfs_client *clp;
608 dprintk("--> nfs4_set_client()\n");
610 if (server->flags & NFS_MOUNT_NORESVPORT)
611 set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
613 /* Allocate or find a client reference we can use */
614 clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
616 error = PTR_ERR(clp);
621 * Query for the lease time on clientid setup or renewal
623 * Note that this will be set on nfs_clients that were created
624 * only for the DS role and did not set this bit, but now will
627 set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
629 server->nfs_client = clp;
630 dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
633 dprintk("<-- nfs4_set_client() = xerror %d\n", error);
638 * Set up a pNFS Data Server client.
640 * Return any existing nfs_client that matches server address,port,version
643 * For a new nfs_client, use a soft mount (default), a low retrans and a
644 * low timeout interval so that if a connection is lost, we retry through
647 struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
648 const struct sockaddr *ds_addr, int ds_addrlen,
649 int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans)
651 struct nfs_client_initdata cl_init = {
653 .addrlen = ds_addrlen,
656 .minorversion = mds_clp->cl_minorversion,
657 .net = mds_clp->cl_net,
659 struct rpc_timeout ds_timeout;
660 struct nfs_client *clp;
663 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
664 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
665 * (section 13.1 RFC 5661).
667 nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
668 clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
669 mds_clp->cl_rpcclient->cl_auth->au_flavor);
671 dprintk("<-- %s %p\n", __func__, clp);
674 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
677 * Session has been established, and the client marked ready.
678 * Set the mount rsize and wsize with negotiated fore channel
679 * attributes which will be bound checked in nfs_server_set_fsinfo.
681 static void nfs4_session_set_rwsize(struct nfs_server *server)
683 #ifdef CONFIG_NFS_V4_1
684 struct nfs4_session *sess;
688 if (!nfs4_has_session(server->nfs_client))
690 sess = server->nfs_client->cl_session;
691 server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
692 server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
694 if (server->rsize > server_resp_sz)
695 server->rsize = server_resp_sz;
696 if (server->wsize > server_rqst_sz)
697 server->wsize = server_rqst_sz;
698 #endif /* CONFIG_NFS_V4_1 */
701 static int nfs4_server_common_setup(struct nfs_server *server,
702 struct nfs_fh *mntfh)
704 struct nfs_fattr *fattr;
707 /* data servers support only a subset of NFSv4.1 */
708 if (is_ds_only_client(server->nfs_client))
709 return -EPROTONOSUPPORT;
711 fattr = nfs_alloc_fattr();
715 /* We must ensure the session is initialised first */
716 error = nfs4_init_session(server);
720 /* Probe the root fh to retrieve its FSID and filehandle */
721 error = nfs4_get_rootfh(server, mntfh);
725 dprintk("Server FSID: %llx:%llx\n",
726 (unsigned long long) server->fsid.major,
727 (unsigned long long) server->fsid.minor);
728 dprintk("Mount FH: %d\n", mntfh->size);
730 nfs4_session_set_rwsize(server);
732 error = nfs_probe_fsinfo(server, mntfh, fattr);
736 if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
737 server->namelen = NFS4_MAXNAMLEN;
739 nfs_server_insert_lists(server);
740 server->mount_time = jiffies;
741 server->destroy = nfs4_destroy_server;
743 nfs_free_fattr(fattr);
748 * Create a version 4 volume record
750 static int nfs4_init_server(struct nfs_server *server,
751 const struct nfs_parsed_mount_data *data)
753 struct rpc_timeout timeparms;
756 dprintk("--> nfs4_init_server()\n");
758 nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
759 data->timeo, data->retrans);
761 /* Initialise the client representation from the mount data */
762 server->flags = data->flags;
763 server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|NFS_CAP_POSIX_LOCK;
764 if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
765 server->caps |= NFS_CAP_READDIRPLUS;
766 server->options = data->options;
768 /* Get a client record */
769 error = nfs4_set_client(server,
770 data->nfs_server.hostname,
771 (const struct sockaddr *)&data->nfs_server.address,
772 data->nfs_server.addrlen,
773 data->client_address,
774 data->auth_flavors[0],
775 data->nfs_server.protocol,
783 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
786 if (nfs4_disable_idmapping && data->auth_flavors[0] == RPC_AUTH_UNIX)
787 server->caps |= NFS_CAP_UIDGID_NOMAP;
790 server->rsize = nfs_block_size(data->rsize, NULL);
792 server->wsize = nfs_block_size(data->wsize, NULL);
794 server->acregmin = data->acregmin * HZ;
795 server->acregmax = data->acregmax * HZ;
796 server->acdirmin = data->acdirmin * HZ;
797 server->acdirmax = data->acdirmax * HZ;
799 server->port = data->nfs_server.port;
801 error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
805 dprintk("<-- nfs4_init_server() = %d\n", error);
810 * Create a version 4 volume record
811 * - keyed on server and FSID
813 /*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
814 struct nfs_fh *mntfh)*/
815 struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
816 struct nfs_subversion *nfs_mod)
818 struct nfs_server *server;
821 dprintk("--> nfs4_create_server()\n");
823 server = nfs_alloc_server();
825 return ERR_PTR(-ENOMEM);
827 /* set up the general RPC client */
828 error = nfs4_init_server(server, mount_info->parsed);
832 error = nfs4_server_common_setup(server, mount_info->mntfh);
836 dprintk("<-- nfs4_create_server() = %p\n", server);
840 nfs_free_server(server);
841 dprintk("<-- nfs4_create_server() = error %d\n", error);
842 return ERR_PTR(error);
846 * Create an NFS4 referral server record
848 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
849 struct nfs_fh *mntfh)
851 struct nfs_client *parent_client;
852 struct nfs_server *server, *parent_server;
855 dprintk("--> nfs4_create_referral_server()\n");
857 server = nfs_alloc_server();
859 return ERR_PTR(-ENOMEM);
861 parent_server = NFS_SB(data->sb);
862 parent_client = parent_server->nfs_client;
864 /* Initialise the client representation from the parent server */
865 nfs_server_copy_userdata(server, parent_server);
866 server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR;
868 /* Get a client representation.
869 * Note: NFSv4 always uses TCP, */
870 error = nfs4_set_client(server, data->hostname,
873 parent_client->cl_ipaddr,
875 rpc_protocol(parent_server->client),
876 parent_server->client->cl_timeout,
877 parent_client->cl_mvops->minor_version,
878 parent_client->cl_net);
882 error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
886 error = nfs4_server_common_setup(server, mntfh);
890 dprintk("<-- nfs_create_referral_server() = %p\n", server);
894 nfs_free_server(server);
895 dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
896 return ERR_PTR(error);