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	/* No matching nfs_client found. */
680	spin_unlock(&nn->nfs_client_lock);
681	dprintk("NFS: <-- %s status = %d\n", __func__, status);
682	nfs_put_client(prev);
683	return status;
684}
685#endif	/* CONFIG_NFS_V4_1 */
686
687static void nfs4_destroy_server(struct nfs_server *server)
688{
689	nfs_server_return_all_delegations(server);
690	unset_pnfs_layoutdriver(server);
691	nfs4_purge_state_owners(server);
692}
693
694/*
695 * NFSv4.0 callback thread helper
696 *
697 * Find a client by callback identifier
698 */
699struct nfs_client *
700nfs4_find_client_ident(struct net *net, int cb_ident)
701{
702	struct nfs_client *clp;
703	struct nfs_net *nn = net_generic(net, nfs_net_id);
704
705	spin_lock(&nn->nfs_client_lock);
706	clp = idr_find(&nn->cb_ident_idr, cb_ident);
707	if (clp)
708		atomic_inc(&clp->cl_count);
709	spin_unlock(&nn->nfs_client_lock);
710	return clp;
711}
712
713#if defined(CONFIG_NFS_V4_1)
714/* Common match routine for v4.0 and v4.1 callback services */
715static bool nfs4_cb_match_client(const struct sockaddr *addr,
716		struct nfs_client *clp, u32 minorversion)
717{
718	struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
719
720	/* Don't match clients that failed to initialise */
721	if (!(clp->cl_cons_state == NFS_CS_READY ||
722	    clp->cl_cons_state == NFS_CS_SESSION_INITING))
723		return false;
724
725	smp_rmb();
726
727	/* Match the version and minorversion */
728	if (clp->rpc_ops->version != 4 ||
729	    clp->cl_minorversion != minorversion)
730		return false;
731
732	/* Match only the IP address, not the port number */
733	if (!nfs_sockaddr_match_ipaddr(addr, clap))
734		return false;
735
736	return true;
737}
738
739/*
740 * NFSv4.1 callback thread helper
741 * For CB_COMPOUND calls, find a client by IP address, protocol version,
742 * minorversion, and sessionID
743 *
744 * Returns NULL if no such client
745 */
746struct nfs_client *
747nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
748			   struct nfs4_sessionid *sid, u32 minorversion)
749{
750	struct nfs_client *clp;
751	struct nfs_net *nn = net_generic(net, nfs_net_id);
752
753	spin_lock(&nn->nfs_client_lock);
754	list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
755		if (nfs4_cb_match_client(addr, clp, minorversion) == false)
756			continue;
757
758		if (!nfs4_has_session(clp))
759			continue;
760
761		/* Match sessionid*/
762		if (memcmp(clp->cl_session->sess_id.data,
763		    sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
764			continue;
765
766		atomic_inc(&clp->cl_count);
767		spin_unlock(&nn->nfs_client_lock);
768		return clp;
769	}
770	spin_unlock(&nn->nfs_client_lock);
771	return NULL;
772}
773
774#else /* CONFIG_NFS_V4_1 */
775
776struct nfs_client *
777nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
778			   struct nfs4_sessionid *sid, u32 minorversion)
779{
780	return NULL;
781}
782#endif /* CONFIG_NFS_V4_1 */
783
784/*
785 * Set up an NFS4 client
786 */
787static int nfs4_set_client(struct nfs_server *server,
788		const char *hostname,
789		const struct sockaddr *addr,
790		const size_t addrlen,
791		const char *ip_addr,
792		rpc_authflavor_t authflavour,
793		int proto, const struct rpc_timeout *timeparms,
794		u32 minorversion, struct net *net)
795{
796	struct nfs_client_initdata cl_init = {
797		.hostname = hostname,
798		.addr = addr,
799		.addrlen = addrlen,
800		.nfs_mod = &nfs_v4,
801		.proto = proto,
802		.minorversion = minorversion,
803		.net = net,
804	};
805	struct nfs_client *clp;
806	int error;
807
808	dprintk("--> nfs4_set_client()\n");
809
810	if (server->flags & NFS_MOUNT_NORESVPORT)
811		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
812	if (server->options & NFS_OPTION_MIGRATION)
813		set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
814
815	/* Allocate or find a client reference we can use */
816	clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
817	if (IS_ERR(clp)) {
818		error = PTR_ERR(clp);
819		goto error;
820	}
821
822	/*
823	 * Query for the lease time on clientid setup or renewal
824	 *
825	 * Note that this will be set on nfs_clients that were created
826	 * only for the DS role and did not set this bit, but now will
827	 * serve a dual role.
828	 */
829	set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
830
831	server->nfs_client = clp;
832	dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
833	return 0;
834error:
835	dprintk("<-- nfs4_set_client() = xerror %d\n", error);
836	return error;
837}
838
839/*
840 * Set up a pNFS Data Server client.
841 *
842 * Return any existing nfs_client that matches server address,port,version
843 * and minorversion.
844 *
845 * For a new nfs_client, use a soft mount (default), a low retrans and a
846 * low timeout interval so that if a connection is lost, we retry through
847 * the MDS.
848 */
849struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
850		const struct sockaddr *ds_addr, int ds_addrlen,
851		int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
852		u32 minor_version, rpc_authflavor_t au_flavor)
853{
854	struct nfs_client_initdata cl_init = {
855		.addr = ds_addr,
856		.addrlen = ds_addrlen,
857		.nfs_mod = &nfs_v4,
858		.proto = ds_proto,
859		.minorversion = minor_version,
860		.net = mds_clp->cl_net,
861	};
862	struct rpc_timeout ds_timeout;
863	struct nfs_client *clp;
864	char buf[INET6_ADDRSTRLEN + 1];
865
866	if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
867		return ERR_PTR(-EINVAL);
868	cl_init.hostname = buf;
869
870	/*
871	 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
872	 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
873	 * (section 13.1 RFC 5661).
874	 */
875	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
876	clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
877			     au_flavor);
878
879	dprintk("<-- %s %p\n", __func__, clp);
880	return clp;
881}
882EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
883
884/*
885 * Session has been established, and the client marked ready.
886 * Set the mount rsize and wsize with negotiated fore channel
887 * attributes which will be bound checked in nfs_server_set_fsinfo.
888 */
889static void nfs4_session_set_rwsize(struct nfs_server *server)
890{
891#ifdef CONFIG_NFS_V4_1
892	struct nfs4_session *sess;
893	u32 server_resp_sz;
894	u32 server_rqst_sz;
895
896	if (!nfs4_has_session(server->nfs_client))
897		return;
898	sess = server->nfs_client->cl_session;
899	server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
900	server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
901
902	if (server->rsize > server_resp_sz)
903		server->rsize = server_resp_sz;
904	if (server->wsize > server_rqst_sz)
905		server->wsize = server_rqst_sz;
906#endif /* CONFIG_NFS_V4_1 */
907}
908
909static int nfs4_server_common_setup(struct nfs_server *server,
910		struct nfs_fh *mntfh, bool auth_probe)
911{
912	struct nfs_fattr *fattr;
913	int error;
914
915	/* data servers support only a subset of NFSv4.1 */
916	if (is_ds_only_client(server->nfs_client))
917		return -EPROTONOSUPPORT;
918
919	fattr = nfs_alloc_fattr();
920	if (fattr == NULL)
921		return -ENOMEM;
922
923	/* We must ensure the session is initialised first */
924	error = nfs4_init_session(server->nfs_client);
925	if (error < 0)
926		goto out;
927
928	/* Set the basic capabilities */
929	server->caps |= server->nfs_client->cl_mvops->init_caps;
930	if (server->flags & NFS_MOUNT_NORDIRPLUS)
931			server->caps &= ~NFS_CAP_READDIRPLUS;
932	/*
933	 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
934	 * authentication.
935	 */
936	if (nfs4_disable_idmapping &&
937			server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
938		server->caps |= NFS_CAP_UIDGID_NOMAP;
939
940
941	/* Probe the root fh to retrieve its FSID and filehandle */
942	error = nfs4_get_rootfh(server, mntfh, auth_probe);
943	if (error < 0)
944		goto out;
945
946	dprintk("Server FSID: %llx:%llx\n",
947			(unsigned long long) server->fsid.major,
948			(unsigned long long) server->fsid.minor);
949	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
950
951	nfs4_session_set_rwsize(server);
952
953	error = nfs_probe_fsinfo(server, mntfh, fattr);
954	if (error < 0)
955		goto out;
956
957	if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
958		server->namelen = NFS4_MAXNAMLEN;
959
960	nfs_server_insert_lists(server);
961	server->mount_time = jiffies;
962	server->destroy = nfs4_destroy_server;
963out:
964	nfs_free_fattr(fattr);
965	return error;
966}
967
968/*
969 * Create a version 4 volume record
970 */
971static int nfs4_init_server(struct nfs_server *server,
972		struct nfs_parsed_mount_data *data)
973{
974	struct rpc_timeout timeparms;
975	int error;
976
977	dprintk("--> nfs4_init_server()\n");
978
979	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
980			data->timeo, data->retrans);
981
982	/* Initialise the client representation from the mount data */
983	server->flags = data->flags;
984	server->options = data->options;
985	server->auth_info = data->auth_info;
986
987	/* Use the first specified auth flavor. If this flavor isn't
988	 * allowed by the server, use the SECINFO path to try the
989	 * other specified flavors */
990	if (data->auth_info.flavor_len >= 1)
991		data->selected_flavor = data->auth_info.flavors[0];
992	else
993		data->selected_flavor = RPC_AUTH_UNIX;
994
995	/* Get a client record */
996	error = nfs4_set_client(server,
997			data->nfs_server.hostname,
998			(const struct sockaddr *)&data->nfs_server.address,
999			data->nfs_server.addrlen,
1000			data->client_address,
1001			data->selected_flavor,
1002			data->nfs_server.protocol,
1003			&timeparms,
1004			data->minorversion,
1005			data->net);
1006	if (error < 0)
1007		goto error;
1008
1009	if (data->rsize)
1010		server->rsize = nfs_block_size(data->rsize, NULL);
1011	if (data->wsize)
1012		server->wsize = nfs_block_size(data->wsize, NULL);
1013
1014	server->acregmin = data->acregmin * HZ;
1015	server->acregmax = data->acregmax * HZ;
1016	server->acdirmin = data->acdirmin * HZ;
1017	server->acdirmax = data->acdirmax * HZ;
1018
1019	server->port = data->nfs_server.port;
1020
1021	error = nfs_init_server_rpcclient(server, &timeparms,
1022					  data->selected_flavor);
1023
1024error:
1025	/* Done */
1026	dprintk("<-- nfs4_init_server() = %d\n", error);
1027	return error;
1028}
1029
1030/*
1031 * Create a version 4 volume record
1032 * - keyed on server and FSID
1033 */
1034/*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1035				      struct nfs_fh *mntfh)*/
1036struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1037				      struct nfs_subversion *nfs_mod)
1038{
1039	struct nfs_server *server;
1040	bool auth_probe;
1041	int error;
1042
1043	dprintk("--> nfs4_create_server()\n");
1044
1045	server = nfs_alloc_server();
1046	if (!server)
1047		return ERR_PTR(-ENOMEM);
1048
1049	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1050
1051	/* set up the general RPC client */
1052	error = nfs4_init_server(server, mount_info->parsed);
1053	if (error < 0)
1054		goto error;
1055
1056	error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1057	if (error < 0)
1058		goto error;
1059
1060	dprintk("<-- nfs4_create_server() = %p\n", server);
1061	return server;
1062
1063error:
1064	nfs_free_server(server);
1065	dprintk("<-- nfs4_create_server() = error %d\n", error);
1066	return ERR_PTR(error);
1067}
1068
1069/*
1070 * Create an NFS4 referral server record
1071 */
1072struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1073					       struct nfs_fh *mntfh)
1074{
1075	struct nfs_client *parent_client;
1076	struct nfs_server *server, *parent_server;
1077	bool auth_probe;
1078	int error;
1079
1080	dprintk("--> nfs4_create_referral_server()\n");
1081
1082	server = nfs_alloc_server();
1083	if (!server)
1084		return ERR_PTR(-ENOMEM);
1085
1086	parent_server = NFS_SB(data->sb);
1087	parent_client = parent_server->nfs_client;
1088
1089	/* Initialise the client representation from the parent server */
1090	nfs_server_copy_userdata(server, parent_server);
1091
1092	/* Get a client representation.
1093	 * Note: NFSv4 always uses TCP, */
1094	error = nfs4_set_client(server, data->hostname,
1095				data->addr,
1096				data->addrlen,
1097				parent_client->cl_ipaddr,
1098				data->authflavor,
1099				rpc_protocol(parent_server->client),
1100				parent_server->client->cl_timeout,
1101				parent_client->cl_mvops->minor_version,
1102				parent_client->cl_net);
1103	if (error < 0)
1104		goto error;
1105
1106	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1107	if (error < 0)
1108		goto error;
1109
1110	auth_probe = parent_server->auth_info.flavor_len < 1;
1111
1112	error = nfs4_server_common_setup(server, mntfh, auth_probe);
1113	if (error < 0)
1114		goto error;
1115
1116	dprintk("<-- nfs_create_referral_server() = %p\n", server);
1117	return server;
1118
1119error:
1120	nfs_free_server(server);
1121	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1122	return ERR_PTR(error);
1123}
1124
1125/*
1126 * Grab the destination's particulars, including lease expiry time.
1127 *
1128 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1129 * we have cached.
1130 */
1131static int nfs_probe_destination(struct nfs_server *server)
1132{
1133	struct inode *inode = d_inode(server->super->s_root);
1134	struct nfs_fattr *fattr;
1135	int error;
1136
1137	fattr = nfs_alloc_fattr();
1138	if (fattr == NULL)
1139		return -ENOMEM;
1140
1141	/* Sanity: the probe won't work if the destination server
1142	 * does not recognize the migrated FH. */
1143	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1144
1145	nfs_free_fattr(fattr);
1146	return error;
1147}
1148
1149/**
1150 * nfs4_update_server - Move an nfs_server to a different nfs_client
1151 *
1152 * @server: represents FSID to be moved
1153 * @hostname: new end-point's hostname
1154 * @sap: new end-point's socket address
1155 * @salen: size of "sap"
1156 * @net: net namespace
1157 *
1158 * The nfs_server must be quiescent before this function is invoked.
1159 * Either its session is drained (NFSv4.1+), or its transport is
1160 * plugged and drained (NFSv4.0).
1161 *
1162 * Returns zero on success, or a negative errno value.
1163 */
1164int nfs4_update_server(struct nfs_server *server, const char *hostname,
1165		       struct sockaddr *sap, size_t salen, struct net *net)
1166{
1167	struct nfs_client *clp = server->nfs_client;
1168	struct rpc_clnt *clnt = server->client;
1169	struct xprt_create xargs = {
1170		.ident		= clp->cl_proto,
1171		.net		= net,
1172		.dstaddr	= sap,
1173		.addrlen	= salen,
1174		.servername	= hostname,
1175	};
1176	char buf[INET6_ADDRSTRLEN + 1];
1177	struct sockaddr_storage address;
1178	struct sockaddr *localaddr = (struct sockaddr *)&address;
1179	int error;
1180
1181	dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
1182			(unsigned long long)server->fsid.major,
1183			(unsigned long long)server->fsid.minor,
1184			hostname);
1185
1186	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1187	if (error != 0) {
1188		dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
1189			__func__, error);
1190		goto out;
1191	}
1192
1193	error = rpc_localaddr(clnt, localaddr, sizeof(address));
1194	if (error != 0) {
1195		dprintk("<-- %s(): rpc_localaddr returned %d\n",
1196			__func__, error);
1197		goto out;
1198	}
1199
1200	error = -EAFNOSUPPORT;
1201	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
1202		dprintk("<-- %s(): rpc_ntop returned %d\n",
1203			__func__, error);
1204		goto out;
1205	}
1206
1207	nfs_server_remove_lists(server);
1208	error = nfs4_set_client(server, hostname, sap, salen, buf,
1209				clp->cl_rpcclient->cl_auth->au_flavor,
1210				clp->cl_proto, clnt->cl_timeout,
1211				clp->cl_minorversion, net);
1212	nfs_put_client(clp);
1213	if (error != 0) {
1214		nfs_server_insert_lists(server);
1215		dprintk("<-- %s(): nfs4_set_client returned %d\n",
1216			__func__, error);
1217		goto out;
1218	}
1219
1220	if (server->nfs_client->cl_hostname == NULL)
1221		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1222	nfs_server_insert_lists(server);
1223
1224	error = nfs_probe_destination(server);
1225	if (error < 0)
1226		goto out;
1227
1228	dprintk("<-- %s() succeeded\n", __func__);
1229
1230out:
1231	return error;
1232}
1233