1/*
2 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
3 * Written by David Howells (dhowells@redhat.com)
4 */
5#include <linux/module.h>
6#include <linux/nfs_fs.h>
7#include <linux/nfs_mount.h>
8#include <linux/sunrpc/addr.h>
9#include <linux/sunrpc/auth.h>
10#include <linux/sunrpc/xprt.h>
11#include <linux/sunrpc/bc_xprt.h>
12#include <linux/sunrpc/rpc_pipe_fs.h>
13#include "internal.h"
14#include "callback.h"
15#include "delegation.h"
16#include "nfs4session.h"
17#include "nfs4idmap.h"
18#include "pnfs.h"
19#include "netns.h"
20
21#define NFSDBG_FACILITY		NFSDBG_CLIENT
22
23/*
24 * Get a unique NFSv4.0 callback identifier which will be used
25 * by the V4.0 callback service to lookup the nfs_client struct
26 */
27static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
28{
29	int ret = 0;
30	struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
31
32	if (clp->rpc_ops->version != 4 || minorversion != 0)
33		return ret;
34	idr_preload(GFP_KERNEL);
35	spin_lock(&nn->nfs_client_lock);
36	ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
37	if (ret >= 0)
38		clp->cl_cb_ident = ret;
39	spin_unlock(&nn->nfs_client_lock);
40	idr_preload_end();
41	return ret < 0 ? ret : 0;
42}
43
44#ifdef CONFIG_NFS_V4_1
45/**
46 * Per auth flavor data server rpc clients
47 */
48struct nfs4_ds_server {
49	struct list_head	list;   /* ds_clp->cl_ds_clients */
50	struct rpc_clnt		*rpc_clnt;
51};
52
53/**
54 * Common lookup case for DS I/O
55 */
56static struct nfs4_ds_server *
57nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
58{
59	struct nfs4_ds_server *dss;
60
61	rcu_read_lock();
62	list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
63		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
64			continue;
65		goto out;
66	}
67	dss = NULL;
68out:
69	rcu_read_unlock();
70	return dss;
71}
72
73static struct nfs4_ds_server *
74nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
75			   struct nfs4_ds_server *new)
76{
77	struct nfs4_ds_server *dss;
78
79	spin_lock(&ds_clp->cl_lock);
80	list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
81		if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
82			continue;
83		goto out;
84	}
85	if (new)
86		list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
87	dss = new;
88out:
89	spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
90	return dss;
91}
92
93static struct nfs4_ds_server *
94nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
95{
96	struct nfs4_ds_server *dss;
97
98	dss = kmalloc(sizeof(*dss), GFP_NOFS);
99	if (dss == NULL)
100		return ERR_PTR(-ENOMEM);
101
102	dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
103	if (IS_ERR(dss->rpc_clnt)) {
104		int err = PTR_ERR(dss->rpc_clnt);
105		kfree (dss);
106		return ERR_PTR(err);
107	}
108	INIT_LIST_HEAD(&dss->list);
109
110	return dss;
111}
112
113static void
114nfs4_free_ds_server(struct nfs4_ds_server *dss)
115{
116	rpc_release_client(dss->rpc_clnt);
117	kfree(dss);
118}
119
120/**
121* Find or create a DS rpc client with th MDS server rpc client auth flavor
122* in the nfs_client cl_ds_clients list.
123*/
124struct rpc_clnt *
125nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
126{
127	struct nfs4_ds_server *dss, *new;
128	rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
129
130	dss = nfs4_find_ds_client(ds_clp, flavor);
131	if (dss != NULL)
132		goto out;
133	new = nfs4_alloc_ds_server(ds_clp, flavor);
134	if (IS_ERR(new))
135		return ERR_CAST(new);
136	dss = nfs4_add_ds_client(ds_clp, flavor, new);
137	if (dss != new)
138		nfs4_free_ds_server(new);
139out:
140	return dss->rpc_clnt;
141}
142EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
143
144static void
145nfs4_shutdown_ds_clients(struct nfs_client *clp)
146{
147	struct nfs4_ds_server *dss;
148	LIST_HEAD(shutdown_list);
149
150	while (!list_empty(&clp->cl_ds_clients)) {
151		dss = list_entry(clp->cl_ds_clients.next,
152					struct nfs4_ds_server, list);
153		list_del(&dss->list);
154		rpc_shutdown_client(dss->rpc_clnt);
155		kfree (dss);
156	}
157}
158
159void nfs41_shutdown_client(struct nfs_client *clp)
160{
161	if (nfs4_has_session(clp)) {
162		nfs4_shutdown_ds_clients(clp);
163		nfs4_destroy_session(clp->cl_session);
164		nfs4_destroy_clientid(clp);
165	}
166
167}
168#endif	/* CONFIG_NFS_V4_1 */
169
170void nfs40_shutdown_client(struct nfs_client *clp)
171{
172	if (clp->cl_slot_tbl) {
173		nfs4_shutdown_slot_table(clp->cl_slot_tbl);
174		kfree(clp->cl_slot_tbl);
175	}
176}
177
178struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
179{
180	int err;
181	struct nfs_client *clp = nfs_alloc_client(cl_init);
182	if (IS_ERR(clp))
183		return clp;
184
185	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
186	if (err)
187		goto error;
188
189	if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
190		err = -EINVAL;
191		goto error;
192	}
193
194	spin_lock_init(&clp->cl_lock);
195	INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
196	INIT_LIST_HEAD(&clp->cl_ds_clients);
197	rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
198	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
199	clp->cl_minorversion = cl_init->minorversion;
200	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
201	clp->cl_mig_gen = 1;
202	return clp;
203
204error:
205	nfs_free_client(clp);
206	return ERR_PTR(err);
207}
208
209/*
210 * Destroy the NFS4 callback service
211 */
212static void nfs4_destroy_callback(struct nfs_client *clp)
213{
214	if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
215		nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
216}
217
218static void nfs4_shutdown_client(struct nfs_client *clp)
219{
220	if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
221		nfs4_kill_renewd(clp);
222	clp->cl_mvops->shutdown_client(clp);
223	nfs4_destroy_callback(clp);
224	if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
225		nfs_idmap_delete(clp);
226
227	rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
228	kfree(clp->cl_serverowner);
229	kfree(clp->cl_serverscope);
230	kfree(clp->cl_implid);
231	kfree(clp->cl_owner_id);
232}
233
234void nfs4_free_client(struct nfs_client *clp)
235{
236	nfs4_shutdown_client(clp);
237	nfs_free_client(clp);
238}
239
240/*
241 * Initialize the NFS4 callback service
242 */
243static int nfs4_init_callback(struct nfs_client *clp)
244{
245	struct rpc_xprt *xprt;
246	int error;
247
248	xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
249
250	if (nfs4_has_session(clp)) {
251		error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
252		if (error < 0)
253			return error;
254	}
255
256	error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
257	if (error < 0) {
258		dprintk("%s: failed to start callback. Error = %d\n",
259			__func__, error);
260		return error;
261	}
262	__set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
263
264	return 0;
265}
266
267/**
268 * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
269 * @clp - nfs_client to initialize
270 *
271 * Returns zero on success, or a negative errno if some error occurred.
272 */
273int nfs40_init_client(struct nfs_client *clp)
274{
275	struct nfs4_slot_table *tbl;
276	int ret;
277
278	tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
279	if (tbl == NULL)
280		return -ENOMEM;
281
282	ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
283					"NFSv4.0 transport Slot table");
284	if (ret) {
285		kfree(tbl);
286		return ret;
287	}
288
289	clp->cl_slot_tbl = tbl;
290	return 0;
291}
292
293#if defined(CONFIG_NFS_V4_1)
294
295/**
296 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
297 * @clp - nfs_client to initialize
298 *
299 * Returns zero on success, or a negative errno if some error occurred.
300 */
301int nfs41_init_client(struct nfs_client *clp)
302{
303	struct nfs4_session *session = NULL;
304
305	/*
306	 * Create the session and mark it expired.
307	 * When a SEQUENCE operation encounters the expired session
308	 * it will do session recovery to initialize it.
309	 */
310	session = nfs4_alloc_session(clp);
311	if (!session)
312		return -ENOMEM;
313
314	clp->cl_session = session;
315
316	/*
317	 * The create session reply races with the server back
318	 * channel probe. Mark the client NFS_CS_SESSION_INITING
319	 * so that the client back channel can find the
320	 * nfs_client struct
321	 */
322	nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
323	return 0;
324}
325
326#endif	/* CONFIG_NFS_V4_1 */
327
328/*
329 * Initialize the minor version specific parts of an NFS4 client record
330 */
331static int nfs4_init_client_minor_version(struct nfs_client *clp)
332{
333	int ret;
334
335	ret = clp->cl_mvops->init_client(clp);
336	if (ret)
337		return ret;
338	return nfs4_init_callback(clp);
339}
340
341/**
342 * nfs4_init_client - Initialise an NFS4 client record
343 *
344 * @clp: nfs_client to initialise
345 * @timeparms: timeout parameters for underlying RPC transport
346 * @ip_addr: callback IP address in presentation format
347 * @authflavor: authentication flavor for underlying RPC transport
348 *
349 * Returns pointer to an NFS client, or an ERR_PTR value.
350 */
351struct nfs_client *nfs4_init_client(struct nfs_client *clp,
352				    const struct rpc_timeout *timeparms,
353				    const char *ip_addr)
354{
355	char buf[INET6_ADDRSTRLEN + 1];
356	struct nfs_client *old;
357	int error;
358
359	if (clp->cl_cons_state == NFS_CS_READY) {
360		/* the client is initialised already */
361		dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
362		return clp;
363	}
364
365	/* Check NFS protocol revision and initialize RPC op vector */
366	clp->rpc_ops = &nfs_v4_clientops;
367
368	if (clp->cl_minorversion != 0)
369		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
370	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
371	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
372
373	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_GSS_KRB5I);
374	if (error == -EINVAL)
375		error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
376	if (error < 0)
377		goto error;
378
379	/* If no clientaddr= option was specified, find a usable cb address */
380	if (ip_addr == NULL) {
381		struct sockaddr_storage cb_addr;
382		struct sockaddr *sap = (struct sockaddr *)&cb_addr;
383
384		error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
385		if (error < 0)
386			goto error;
387		error = rpc_ntop(sap, buf, sizeof(buf));
388		if (error < 0)
389			goto error;
390		ip_addr = (const char *)buf;
391	}
392	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
393
394	error = nfs_idmap_new(clp);
395	if (error < 0) {
396		dprintk("%s: failed to create idmapper. Error = %d\n",
397			__func__, error);
398		goto error;
399	}
400	__set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
401
402	error = nfs4_init_client_minor_version(clp);
403	if (error < 0)
404		goto error;
405
406	if (!nfs4_has_session(clp))
407		nfs_mark_client_ready(clp, NFS_CS_READY);
408
409	error = nfs4_discover_server_trunking(clp, &old);
410	if (error < 0)
411		goto error;
412
413	if (clp != old)
414		clp->cl_preserve_clid = true;
415	nfs_put_client(clp);
416	return old;
417
418error:
419	nfs_mark_client_ready(clp, error);
420	nfs_put_client(clp);
421	dprintk("<-- nfs4_init_client() = xerror %d\n", error);
422	return ERR_PTR(error);
423}
424
425/*
426 * SETCLIENTID just did a callback update with the callback ident in
427 * "drop," but server trunking discovery claims "drop" and "keep" are
428 * actually the same server.  Swap the callback IDs so that "keep"
429 * will continue to use the callback ident the server now knows about,
430 * and so that "keep"'s original callback ident is destroyed when
431 * "drop" is freed.
432 */
433static void nfs4_swap_callback_idents(struct nfs_client *keep,
434				      struct nfs_client *drop)
435{
436	struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
437	unsigned int save = keep->cl_cb_ident;
438
439	if (keep->cl_cb_ident == drop->cl_cb_ident)
440		return;
441
442	dprintk("%s: keeping callback ident %u and dropping ident %u\n",
443		__func__, keep->cl_cb_ident, drop->cl_cb_ident);
444
445	spin_lock(&nn->nfs_client_lock);
446
447	idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
448	keep->cl_cb_ident = drop->cl_cb_ident;
449
450	idr_replace(&nn->cb_ident_idr, drop, save);
451	drop->cl_cb_ident = save;
452
453	spin_unlock(&nn->nfs_client_lock);
454}
455
456static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
457		const struct nfs_client *clp2)
458{
459	if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
460		return true;
461	return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
462}
463
464/**
465 * nfs40_walk_client_list - Find server that recognizes a client ID
466 *
467 * @new: nfs_client with client ID to test
468 * @result: OUT: found nfs_client, or new
469 * @cred: credential to use for trunking test
470 *
471 * Returns zero, a negative errno, or a negative NFS4ERR status.
472 * If zero is returned, an nfs_client pointer is planted in "result."
473 *
474 * NB: nfs40_walk_client_list() relies on the new nfs_client being
475 *     the last nfs_client on the list.
476 */
477int nfs40_walk_client_list(struct nfs_client *new,
478			   struct nfs_client **result,
479			   struct rpc_cred *cred)
480{
481	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
482	struct nfs_client *pos, *prev = NULL;
483	struct nfs4_setclientid_res clid = {
484		.clientid	= new->cl_clientid,
485		.confirm	= new->cl_confirm,
486	};
487	int status = -NFS4ERR_STALE_CLIENTID;
488
489	spin_lock(&nn->nfs_client_lock);
490	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
491
492		if (pos->rpc_ops != new->rpc_ops)
493			continue;
494
495		if (pos->cl_minorversion != new->cl_minorversion)
496			continue;
497
498		/* If "pos" isn't marked ready, we can't trust the
499		 * remaining fields in "pos" */
500		if (pos->cl_cons_state > NFS_CS_READY) {
501			atomic_inc(&pos->cl_count);
502			spin_unlock(&nn->nfs_client_lock);
503
504			nfs_put_client(prev);
505			prev = pos;
506
507			status = nfs_wait_client_init_complete(pos);
508			if (status < 0)
509				goto out;
510			status = -NFS4ERR_STALE_CLIENTID;
511			spin_lock(&nn->nfs_client_lock);
512		}
513		if (pos->cl_cons_state != NFS_CS_READY)
514			continue;
515
516		if (pos->cl_clientid != new->cl_clientid)
517			continue;
518
519		if (!nfs4_match_client_owner_id(pos, new))
520			continue;
521
522		atomic_inc(&pos->cl_count);
523		spin_unlock(&nn->nfs_client_lock);
524
525		nfs_put_client(prev);
526		prev = pos;
527
528		status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
529		switch (status) {
530		case -NFS4ERR_STALE_CLIENTID:
531			break;
532		case 0:
533			nfs4_swap_callback_idents(pos, new);
534
535			prev = NULL;
536			*result = pos;
537			dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
538				__func__, pos, atomic_read(&pos->cl_count));
539			goto out;
540		case -ERESTARTSYS:
541		case -ETIMEDOUT:
542			/* The callback path may have been inadvertently
543			 * changed. Schedule recovery!
544			 */
545			nfs4_schedule_path_down_recovery(pos);
546		default:
547			goto out;
548		}
549
550		spin_lock(&nn->nfs_client_lock);
551	}
552	spin_unlock(&nn->nfs_client_lock);
553
554	/* No match found. The server lost our clientid */
555out:
556	nfs_put_client(prev);
557	dprintk("NFS: <-- %s status = %d\n", __func__, status);
558	return status;
559}
560
561#ifdef CONFIG_NFS_V4_1
562/*
563 * Returns true if the client IDs match
564 */
565static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
566{
567	if (a->cl_clientid != b->cl_clientid) {
568		dprintk("NFS: --> %s client ID %llx does not match %llx\n",
569			__func__, a->cl_clientid, b->cl_clientid);
570		return false;
571	}
572	dprintk("NFS: --> %s client ID %llx matches %llx\n",
573		__func__, a->cl_clientid, b->cl_clientid);
574	return true;
575}
576
577/*
578 * Returns true if the server major ids match
579 */
580static bool
581nfs4_check_clientid_trunking(struct nfs_client *a, struct nfs_client *b)
582{
583	struct nfs41_server_owner *o1 = a->cl_serverowner;
584	struct nfs41_server_owner *o2 = b->cl_serverowner;
585
586	if (o1->major_id_sz != o2->major_id_sz)
587		goto out_major_mismatch;
588	if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
589		goto out_major_mismatch;
590
591	dprintk("NFS: --> %s server owners match\n", __func__);
592	return true;
593
594out_major_mismatch:
595	dprintk("NFS: --> %s server owner major IDs do not match\n",
596		__func__);
597	return false;
598}
599
600/**
601 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
602 *
603 * @new: nfs_client with client ID to test
604 * @result: OUT: found nfs_client, or new
605 * @cred: credential to use for trunking test
606 *
607 * Returns zero, a negative errno, or a negative NFS4ERR status.
608 * If zero is returned, an nfs_client pointer is planted in "result."
609 *
610 * NB: nfs41_walk_client_list() relies on the new nfs_client being
611 *     the last nfs_client on the list.
612 */
613int nfs41_walk_client_list(struct nfs_client *new,
614			   struct nfs_client **result,
615			   struct rpc_cred *cred)
616{
617	struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
618	struct nfs_client *pos, *prev = NULL;
619	int status = -NFS4ERR_STALE_CLIENTID;
620
621	spin_lock(&nn->nfs_client_lock);
622	list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
623
624		if (pos == new)
625			goto found;
626
627		if (pos->rpc_ops != new->rpc_ops)
628			continue;
629
630		if (pos->cl_minorversion != new->cl_minorversion)
631			continue;
632
633		/* If "pos" isn't marked ready, we can't trust the
634		 * remaining fields in "pos", especially the client
635		 * ID and serverowner fields.  Wait for CREATE_SESSION
636		 * to finish. */
637		if (pos->cl_cons_state > NFS_CS_READY) {
638			atomic_inc(&pos->cl_count);
639			spin_unlock(&nn->nfs_client_lock);
640
641			nfs_put_client(prev);
642			prev = pos;
643
644			status = nfs_wait_client_init_complete(pos);
645			spin_lock(&nn->nfs_client_lock);
646			if (status < 0)
647				break;
648			status = -NFS4ERR_STALE_CLIENTID;
649		}
650		if (pos->cl_cons_state != NFS_CS_READY)
651			continue;
652
653		if (!nfs4_match_clientids(pos, new))
654			continue;
655
656		/*
657		 * Note that session trunking is just a special subcase of
658		 * client id trunking. In either case, we want to fall back
659		 * to using the existing nfs_client.
660		 */
661		if (!nfs4_check_clientid_trunking(pos, new))
662			continue;
663
664		/* Unlike NFSv4.0, we know that NFSv4.1 always uses the
665		 * uniform string, however someone might switch the
666		 * uniquifier string on us.
667		 */
668		if (!nfs4_match_client_owner_id(pos, new))
669			continue;
670found:
671		atomic_inc(&pos->cl_count);
672		*result = pos;
673		status = 0;
674		dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
675			__func__, pos, atomic_read(&pos->cl_count));
676		break;
677	}
678
679	spin_unlock(&nn->nfs_client_lock);
680	dprintk("NFS: <-- %s status = %d\n", __func__, status);
681	nfs_put_client(prev);
682	return status;
683}
684#endif	/* CONFIG_NFS_V4_1 */
685
686static void nfs4_destroy_server(struct nfs_server *server)
687{
688	nfs_server_return_all_delegations(server);
689	unset_pnfs_layoutdriver(server);
690	nfs4_purge_state_owners(server);
691}
692
693/*
694 * NFSv4.0 callback thread helper
695 *
696 * Find a client by callback identifier
697 */
698struct nfs_client *
699nfs4_find_client_ident(struct net *net, int cb_ident)
700{
701	struct nfs_client *clp;
702	struct nfs_net *nn = net_generic(net, nfs_net_id);
703
704	spin_lock(&nn->nfs_client_lock);
705	clp = idr_find(&nn->cb_ident_idr, cb_ident);
706	if (clp)
707		atomic_inc(&clp->cl_count);
708	spin_unlock(&nn->nfs_client_lock);
709	return clp;
710}
711
712#if defined(CONFIG_NFS_V4_1)
713/* Common match routine for v4.0 and v4.1 callback services */
714static bool nfs4_cb_match_client(const struct sockaddr *addr,
715		struct nfs_client *clp, u32 minorversion)
716{
717	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
718
719	/* Don't match clients that failed to initialise */
720	if (!(clp->cl_cons_state == NFS_CS_READY ||
721	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
722		return false;
723
724	smp_rmb();
725
726	/* Match the version and minorversion */
727	if (clp->rpc_ops->version != 4 ||
728	    clp->cl_minorversion != minorversion)
729		return false;
730
731	/* Match only the IP address, not the port number */
732	return rpc_cmp_addr(addr, clap);
733}
734
735/*
736 * NFSv4.1 callback thread helper
737 * For CB_COMPOUND calls, find a client by IP address, protocol version,
738 * minorversion, and sessionID
739 *
740 * Returns NULL if no such client
741 */
742struct nfs_client *
743nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
744			   struct nfs4_sessionid *sid, u32 minorversion)
745{
746	struct nfs_client *clp;
747	struct nfs_net *nn = net_generic(net, nfs_net_id);
748
749	spin_lock(&nn->nfs_client_lock);
750	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
751		if (nfs4_cb_match_client(addr, clp, minorversion) == false)
752			continue;
753
754		if (!nfs4_has_session(clp))
755			continue;
756
757		/* Match sessionid*/
758		if (memcmp(clp->cl_session->sess_id.data,
759		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
760			continue;
761
762		atomic_inc(&clp->cl_count);
763		spin_unlock(&nn->nfs_client_lock);
764		return clp;
765	}
766	spin_unlock(&nn->nfs_client_lock);
767	return NULL;
768}
769
770#else /* CONFIG_NFS_V4_1 */
771
772struct nfs_client *
773nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
774			   struct nfs4_sessionid *sid, u32 minorversion)
775{
776	return NULL;
777}
778#endif /* CONFIG_NFS_V4_1 */
779
780/*
781 * Set up an NFS4 client
782 */
783static int nfs4_set_client(struct nfs_server *server,
784		const char *hostname,
785		const struct sockaddr *addr,
786		const size_t addrlen,
787		const char *ip_addr,
788		rpc_authflavor_t authflavour,
789		int proto, const struct rpc_timeout *timeparms,
790		u32 minorversion, struct net *net)
791{
792	struct nfs_client_initdata cl_init = {
793		.hostname = hostname,
794		.addr = addr,
795		.addrlen = addrlen,
796		.nfs_mod = &nfs_v4,
797		.proto = proto,
798		.minorversion = minorversion,
799		.net = net,
800	};
801	struct nfs_client *clp;
802	int error;
803
804	dprintk("--> nfs4_set_client()\n");
805
806	if (server->flags & NFS_MOUNT_NORESVPORT)
807		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
808	if (server->options & NFS_OPTION_MIGRATION)
809		set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
810
811	/* Allocate or find a client reference we can use */
812	clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
813	if (IS_ERR(clp)) {
814		error = PTR_ERR(clp);
815		goto error;
816	}
817
818	/*
819	 * Query for the lease time on clientid setup or renewal
820	 *
821	 * Note that this will be set on nfs_clients that were created
822	 * only for the DS role and did not set this bit, but now will
823	 * serve a dual role.
824	 */
825	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
826
827	server->nfs_client = clp;
828	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
829	return 0;
830error:
831	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
832	return error;
833}
834
835/*
836 * Set up a pNFS Data Server client.
837 *
838 * Return any existing nfs_client that matches server address,port,version
839 * and minorversion.
840 *
841 * For a new nfs_client, use a soft mount (default), a low retrans and a
842 * low timeout interval so that if a connection is lost, we retry through
843 * the MDS.
844 */
845struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
846		const struct sockaddr *ds_addr, int ds_addrlen,
847		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
848		u32 minor_version, rpc_authflavor_t au_flavor)
849{
850	struct nfs_client_initdata cl_init = {
851		.addr = ds_addr,
852		.addrlen = ds_addrlen,
853		.nfs_mod = &nfs_v4,
854		.proto = ds_proto,
855		.minorversion = minor_version,
856		.net = mds_clp->cl_net,
857	};
858	struct rpc_timeout ds_timeout;
859	struct nfs_client *clp;
860	char buf[INET6_ADDRSTRLEN + 1];
861
862	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
863		return ERR_PTR(-EINVAL);
864	cl_init.hostname = buf;
865
866	/*
867	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
868	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
869	 * (section 13.1 RFC 5661).
870	 */
871	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
872	clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
873			     au_flavor);
874
875	dprintk("<-- %s %p\n", __func__, clp);
876	return clp;
877}
878EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
879
880/*
881 * Session has been established, and the client marked ready.
882 * Set the mount rsize and wsize with negotiated fore channel
883 * attributes which will be bound checked in nfs_server_set_fsinfo.
884 */
885static void nfs4_session_set_rwsize(struct nfs_server *server)
886{
887#ifdef CONFIG_NFS_V4_1
888	struct nfs4_session *sess;
889	u32 server_resp_sz;
890	u32 server_rqst_sz;
891
892	if (!nfs4_has_session(server->nfs_client))
893		return;
894	sess = server->nfs_client->cl_session;
895	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
896	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
897
898	if (server->rsize > server_resp_sz)
899		server->rsize = server_resp_sz;
900	if (server->wsize > server_rqst_sz)
901		server->wsize = server_rqst_sz;
902#endif /* CONFIG_NFS_V4_1 */
903}
904
905static int nfs4_server_common_setup(struct nfs_server *server,
906		struct nfs_fh *mntfh, bool auth_probe)
907{
908	struct nfs_fattr *fattr;
909	int error;
910
911	/* data servers support only a subset of NFSv4.1 */
912	if (is_ds_only_client(server->nfs_client))
913		return -EPROTONOSUPPORT;
914
915	fattr = nfs_alloc_fattr();
916	if (fattr == NULL)
917		return -ENOMEM;
918
919	/* We must ensure the session is initialised first */
920	error = nfs4_init_session(server->nfs_client);
921	if (error < 0)
922		goto out;
923
924	/* Set the basic capabilities */
925	server->caps |= server->nfs_client->cl_mvops->init_caps;
926	if (server->flags & NFS_MOUNT_NORDIRPLUS)
927			server->caps &= ~NFS_CAP_READDIRPLUS;
928	/*
929	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
930	 * authentication.
931	 */
932	if (nfs4_disable_idmapping &&
933			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
934		server->caps |= NFS_CAP_UIDGID_NOMAP;
935
936
937	/* Probe the root fh to retrieve its FSID and filehandle */
938	error = nfs4_get_rootfh(server, mntfh, auth_probe);
939	if (error < 0)
940		goto out;
941
942	dprintk("Server FSID: %llx:%llx\n",
943			(unsigned long long) server->fsid.major,
944			(unsigned long long) server->fsid.minor);
945	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
946
947	nfs4_session_set_rwsize(server);
948
949	error = nfs_probe_fsinfo(server, mntfh, fattr);
950	if (error < 0)
951		goto out;
952
953	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
954		server->namelen = NFS4_MAXNAMLEN;
955
956	nfs_server_insert_lists(server);
957	server->mount_time = jiffies;
958	server->destroy = nfs4_destroy_server;
959out:
960	nfs_free_fattr(fattr);
961	return error;
962}
963
964/*
965 * Create a version 4 volume record
966 */
967static int nfs4_init_server(struct nfs_server *server,
968		struct nfs_parsed_mount_data *data)
969{
970	struct rpc_timeout timeparms;
971	int error;
972
973	dprintk("--> nfs4_init_server()\n");
974
975	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
976			data->timeo, data->retrans);
977
978	/* Initialise the client representation from the mount data */
979	server->flags = data->flags;
980	server->options = data->options;
981	server->auth_info = data->auth_info;
982
983	/* Use the first specified auth flavor. If this flavor isn't
984	 * allowed by the server, use the SECINFO path to try the
985	 * other specified flavors */
986	if (data->auth_info.flavor_len >= 1)
987		data->selected_flavor = data->auth_info.flavors[0];
988	else
989		data->selected_flavor = RPC_AUTH_UNIX;
990
991	/* Get a client record */
992	error = nfs4_set_client(server,
993			data->nfs_server.hostname,
994			(const struct sockaddr *)&data->nfs_server.address,
995			data->nfs_server.addrlen,
996			data->client_address,
997			data->selected_flavor,
998			data->nfs_server.protocol,
999			&timeparms,
1000			data->minorversion,
1001			data->net);
1002	if (error < 0)
1003		goto error;
1004
1005	if (data->rsize)
1006		server->rsize = nfs_block_size(data->rsize, NULL);
1007	if (data->wsize)
1008		server->wsize = nfs_block_size(data->wsize, NULL);
1009
1010	server->acregmin = data->acregmin * HZ;
1011	server->acregmax = data->acregmax * HZ;
1012	server->acdirmin = data->acdirmin * HZ;
1013	server->acdirmax = data->acdirmax * HZ;
1014
1015	server->port = data->nfs_server.port;
1016
1017	error = nfs_init_server_rpcclient(server, &timeparms,
1018					  data->selected_flavor);
1019
1020error:
1021	/* Done */
1022	dprintk("<-- nfs4_init_server() = %d\n", error);
1023	return error;
1024}
1025
1026/*
1027 * Create a version 4 volume record
1028 * - keyed on server and FSID
1029 */
1030/*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1031				      struct nfs_fh *mntfh)*/
1032struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1033				      struct nfs_subversion *nfs_mod)
1034{
1035	struct nfs_server *server;
1036	bool auth_probe;
1037	int error;
1038
1039	dprintk("--> nfs4_create_server()\n");
1040
1041	server = nfs_alloc_server();
1042	if (!server)
1043		return ERR_PTR(-ENOMEM);
1044
1045	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1046
1047	/* set up the general RPC client */
1048	error = nfs4_init_server(server, mount_info->parsed);
1049	if (error < 0)
1050		goto error;
1051
1052	error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1053	if (error < 0)
1054		goto error;
1055
1056	dprintk("<-- nfs4_create_server() = %p\n", server);
1057	return server;
1058
1059error:
1060	nfs_free_server(server);
1061	dprintk("<-- nfs4_create_server() = error %d\n", error);
1062	return ERR_PTR(error);
1063}
1064
1065/*
1066 * Create an NFS4 referral server record
1067 */
1068struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1069					       struct nfs_fh *mntfh)
1070{
1071	struct nfs_client *parent_client;
1072	struct nfs_server *server, *parent_server;
1073	bool auth_probe;
1074	int error;
1075
1076	dprintk("--> nfs4_create_referral_server()\n");
1077
1078	server = nfs_alloc_server();
1079	if (!server)
1080		return ERR_PTR(-ENOMEM);
1081
1082	parent_server = NFS_SB(data->sb);
1083	parent_client = parent_server->nfs_client;
1084
1085	/* Initialise the client representation from the parent server */
1086	nfs_server_copy_userdata(server, parent_server);
1087
1088	/* Get a client representation.
1089	 * Note: NFSv4 always uses TCP, */
1090	error = nfs4_set_client(server, data->hostname,
1091				data->addr,
1092				data->addrlen,
1093				parent_client->cl_ipaddr,
1094				data->authflavor,
1095				rpc_protocol(parent_server->client),
1096				parent_server->client->cl_timeout,
1097				parent_client->cl_mvops->minor_version,
1098				parent_client->cl_net);
1099	if (error < 0)
1100		goto error;
1101
1102	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1103	if (error < 0)
1104		goto error;
1105
1106	auth_probe = parent_server->auth_info.flavor_len < 1;
1107
1108	error = nfs4_server_common_setup(server, mntfh, auth_probe);
1109	if (error < 0)
1110		goto error;
1111
1112	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1113	return server;
1114
1115error:
1116	nfs_free_server(server);
1117	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1118	return ERR_PTR(error);
1119}
1120
1121/*
1122 * Grab the destination's particulars, including lease expiry time.
1123 *
1124 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1125 * we have cached.
1126 */
1127static int nfs_probe_destination(struct nfs_server *server)
1128{
1129	struct inode *inode = d_inode(server->super->s_root);
1130	struct nfs_fattr *fattr;
1131	int error;
1132
1133	fattr = nfs_alloc_fattr();
1134	if (fattr == NULL)
1135		return -ENOMEM;
1136
1137	/* Sanity: the probe won't work if the destination server
1138	 * does not recognize the migrated FH. */
1139	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1140
1141	nfs_free_fattr(fattr);
1142	return error;
1143}
1144
1145/**
1146 * nfs4_update_server - Move an nfs_server to a different nfs_client
1147 *
1148 * @server: represents FSID to be moved
1149 * @hostname: new end-point's hostname
1150 * @sap: new end-point's socket address
1151 * @salen: size of "sap"
1152 * @net: net namespace
1153 *
1154 * The nfs_server must be quiescent before this function is invoked.
1155 * Either its session is drained (NFSv4.1+), or its transport is
1156 * plugged and drained (NFSv4.0).
1157 *
1158 * Returns zero on success, or a negative errno value.
1159 */
1160int nfs4_update_server(struct nfs_server *server, const char *hostname,
1161		       struct sockaddr *sap, size_t salen, struct net *net)
1162{
1163	struct nfs_client *clp = server->nfs_client;
1164	struct rpc_clnt *clnt = server->client;
1165	struct xprt_create xargs = {
1166		.ident		= clp->cl_proto,
1167		.net		= net,
1168		.dstaddr	= sap,
1169		.addrlen	= salen,
1170		.servername	= hostname,
1171	};
1172	char buf[INET6_ADDRSTRLEN + 1];
1173	struct sockaddr_storage address;
1174	struct sockaddr *localaddr = (struct sockaddr *)&address;
1175	int error;
1176
1177	dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
1178			(unsigned long long)server->fsid.major,
1179			(unsigned long long)server->fsid.minor,
1180			hostname);
1181
1182	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1183	if (error != 0) {
1184		dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
1185			__func__, error);
1186		goto out;
1187	}
1188
1189	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1190	if (error != 0) {
1191		dprintk("<-- %s(): rpc_localaddr returned %d\n",
1192			__func__, error);
1193		goto out;
1194	}
1195
1196	error = -EAFNOSUPPORT;
1197	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
1198		dprintk("<-- %s(): rpc_ntop returned %d\n",
1199			__func__, error);
1200		goto out;
1201	}
1202
1203	nfs_server_remove_lists(server);
1204	error = nfs4_set_client(server, hostname, sap, salen, buf,
1205				clp->cl_rpcclient->cl_auth->au_flavor,
1206				clp->cl_proto, clnt->cl_timeout,
1207				clp->cl_minorversion, net);
1208	nfs_put_client(clp);
1209	if (error != 0) {
1210		nfs_server_insert_lists(server);
1211		dprintk("<-- %s(): nfs4_set_client returned %d\n",
1212			__func__, error);
1213		goto out;
1214	}
1215
1216	if (server->nfs_client->cl_hostname == NULL)
1217		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1218	nfs_server_insert_lists(server);
1219
1220	error = nfs_probe_destination(server);
1221	if (error < 0)
1222		goto out;
1223
1224	dprintk("<-- %s() succeeded\n", __func__);
1225
1226out:
1227	return error;
1228}
1229