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1// SPDX-License-Identifier: GPL-2.0-or-later
2/* client.c: NFS client sharing and management code
3 *
4 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/sched.h>
12#include <linux/time.h>
13#include <linux/kernel.h>
14#include <linux/mm.h>
15#include <linux/string.h>
16#include <linux/stat.h>
17#include <linux/errno.h>
18#include <linux/unistd.h>
19#include <linux/sunrpc/addr.h>
20#include <linux/sunrpc/clnt.h>
21#include <linux/sunrpc/stats.h>
22#include <linux/sunrpc/metrics.h>
23#include <linux/sunrpc/xprtsock.h>
24#include <linux/sunrpc/xprtrdma.h>
25#include <linux/nfs_fs.h>
26#include <linux/nfs_mount.h>
27#include <linux/nfs4_mount.h>
28#include <linux/lockd/bind.h>
29#include <linux/seq_file.h>
30#include <linux/mount.h>
31#include <linux/vfs.h>
32#include <linux/inet.h>
33#include <linux/in6.h>
34#include <linux/slab.h>
35#include <linux/idr.h>
36#include <net/ipv6.h>
37#include <linux/nfs_xdr.h>
38#include <linux/sunrpc/bc_xprt.h>
39#include <linux/nsproxy.h>
40#include <linux/pid_namespace.h>
41#include <linux/nfslocalio.h>
42
43#include "nfs4_fs.h"
44#include "callback.h"
45#include "delegation.h"
46#include "iostat.h"
47#include "internal.h"
48#include "fscache.h"
49#include "pnfs.h"
50#include "nfs.h"
51#include "netns.h"
52#include "sysfs.h"
53#include "nfs42.h"
54
55#define NFSDBG_FACILITY NFSDBG_CLIENT
56
57static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
58static DEFINE_RWLOCK(nfs_version_lock);
59
60static struct nfs_subversion *nfs_version_mods[5] = {
61 [2] = NULL,
62 [3] = NULL,
63 [4] = NULL,
64};
65
66/*
67 * RPC cruft for NFS
68 */
69static const struct rpc_version *nfs_version[5] = {
70 [2] = NULL,
71 [3] = NULL,
72 [4] = NULL,
73};
74
75const struct rpc_program nfs_program = {
76 .name = "nfs",
77 .number = NFS_PROGRAM,
78 .nrvers = ARRAY_SIZE(nfs_version),
79 .version = nfs_version,
80 .pipe_dir_name = NFS_PIPE_DIRNAME,
81};
82
83static struct nfs_subversion *__find_nfs_version(unsigned int version)
84{
85 struct nfs_subversion *nfs;
86
87 read_lock(&nfs_version_lock);
88 nfs = nfs_version_mods[version];
89 read_unlock(&nfs_version_lock);
90 return nfs;
91}
92
93struct nfs_subversion *find_nfs_version(unsigned int version)
94{
95 struct nfs_subversion *nfs = __find_nfs_version(version);
96
97 if (!nfs && request_module("nfsv%d", version) == 0)
98 nfs = __find_nfs_version(version);
99
100 if (!nfs)
101 return ERR_PTR(error: -EPROTONOSUPPORT);
102
103 if (!get_nfs_version(nfs))
104 return ERR_PTR(error: -EAGAIN);
105
106 return nfs;
107}
108
109int get_nfs_version(struct nfs_subversion *nfs)
110{
111 return try_module_get(module: nfs->owner);
112}
113EXPORT_SYMBOL_GPL(get_nfs_version);
114
115void put_nfs_version(struct nfs_subversion *nfs)
116{
117 module_put(module: nfs->owner);
118}
119
120void register_nfs_version(struct nfs_subversion *nfs)
121{
122 write_lock(&nfs_version_lock);
123
124 nfs_version_mods[nfs->rpc_ops->version] = nfs;
125 nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
126
127 write_unlock(&nfs_version_lock);
128}
129EXPORT_SYMBOL_GPL(register_nfs_version);
130
131void unregister_nfs_version(struct nfs_subversion *nfs)
132{
133 write_lock(&nfs_version_lock);
134
135 nfs_version[nfs->rpc_ops->version] = NULL;
136 nfs_version_mods[nfs->rpc_ops->version] = NULL;
137
138 write_unlock(&nfs_version_lock);
139}
140EXPORT_SYMBOL_GPL(unregister_nfs_version);
141
142/*
143 * Allocate a shared client record
144 *
145 * Since these are allocated/deallocated very rarely, we don't
146 * bother putting them in a slab cache...
147 */
148struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
149{
150 struct nfs_client *clp;
151 int err = -ENOMEM;
152
153 if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
154 goto error_0;
155
156 clp->cl_minorversion = cl_init->minorversion;
157 clp->cl_nfs_mod = cl_init->nfs_mod;
158 if (!get_nfs_version(clp->cl_nfs_mod))
159 goto error_dealloc;
160
161 clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
162
163 refcount_set(r: &clp->cl_count, n: 1);
164 clp->cl_cons_state = NFS_CS_INITING;
165
166 memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
167 clp->cl_addrlen = cl_init->addrlen;
168
169 if (cl_init->hostname) {
170 err = -ENOMEM;
171 clp->cl_hostname = kstrdup(s: cl_init->hostname, GFP_KERNEL);
172 if (!clp->cl_hostname)
173 goto error_cleanup;
174 }
175
176 INIT_LIST_HEAD(list: &clp->cl_superblocks);
177 clp->cl_rpcclient = ERR_PTR(error: -EINVAL);
178
179 clp->cl_flags = cl_init->init_flags;
180 clp->cl_proto = cl_init->proto;
181 clp->cl_nconnect = cl_init->nconnect;
182 clp->cl_max_connect = cl_init->max_connect ? cl_init->max_connect : 1;
183 clp->cl_net = get_net_track(net: cl_init->net, tracker: &clp->cl_ns_tracker, GFP_KERNEL);
184
185#if IS_ENABLED(CONFIG_NFS_LOCALIO)
186 seqlock_init(&clp->cl_boot_lock);
187 ktime_get_real_ts64(tv: &clp->cl_nfssvc_boot);
188 nfs_uuid_init(&clp->cl_uuid);
189 INIT_WORK(&clp->cl_local_probe_work, nfs_local_probe_async_work);
190#endif /* CONFIG_NFS_LOCALIO */
191
192 clp->cl_principal = "*";
193 clp->cl_xprtsec = cl_init->xprtsec;
194 return clp;
195
196error_cleanup:
197 put_nfs_version(nfs: clp->cl_nfs_mod);
198error_dealloc:
199 kfree(objp: clp);
200error_0:
201 return ERR_PTR(error: err);
202}
203EXPORT_SYMBOL_GPL(nfs_alloc_client);
204
205#if IS_ENABLED(CONFIG_NFS_V4)
206static void nfs_cleanup_cb_ident_idr(struct net *net)
207{
208 struct nfs_net *nn = net_generic(net, id: nfs_net_id);
209
210 idr_destroy(&nn->cb_ident_idr);
211}
212
213/* nfs_client_lock held */
214static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
215{
216 struct nfs_net *nn = net_generic(net: clp->cl_net, id: nfs_net_id);
217
218 if (clp->cl_cb_ident)
219 idr_remove(&nn->cb_ident_idr, id: clp->cl_cb_ident);
220}
221
222static void pnfs_init_server(struct nfs_server *server)
223{
224 rpc_init_wait_queue(&server->roc_rpcwaitq, "pNFS ROC");
225}
226
227#else
228static void nfs_cleanup_cb_ident_idr(struct net *net)
229{
230}
231
232static void nfs_cb_idr_remove_locked(struct nfs_client *clp)
233{
234}
235
236static void pnfs_init_server(struct nfs_server *server)
237{
238}
239
240#endif /* CONFIG_NFS_V4 */
241
242/*
243 * Destroy a shared client record
244 */
245void nfs_free_client(struct nfs_client *clp)
246{
247 nfs_localio_disable_client(clp);
248
249 /* -EIO all pending I/O */
250 if (!IS_ERR(ptr: clp->cl_rpcclient))
251 rpc_shutdown_client(clp->cl_rpcclient);
252
253 put_net_track(net: clp->cl_net, tracker: &clp->cl_ns_tracker);
254 put_nfs_version(nfs: clp->cl_nfs_mod);
255 kfree(objp: clp->cl_hostname);
256 kfree(objp: clp->cl_acceptor);
257 kfree_rcu(clp, rcu);
258}
259EXPORT_SYMBOL_GPL(nfs_free_client);
260
261/*
262 * Release a reference to a shared client record
263 */
264void nfs_put_client(struct nfs_client *clp)
265{
266 struct nfs_net *nn;
267
268 if (!clp)
269 return;
270
271 nn = net_generic(net: clp->cl_net, id: nfs_net_id);
272
273 if (refcount_dec_and_lock(r: &clp->cl_count, lock: &nn->nfs_client_lock)) {
274 list_del(entry: &clp->cl_share_link);
275 nfs_cb_idr_remove_locked(clp);
276 spin_unlock(lock: &nn->nfs_client_lock);
277
278 WARN_ON_ONCE(!list_empty(&clp->cl_superblocks));
279
280 clp->rpc_ops->free_client(clp);
281 }
282}
283EXPORT_SYMBOL_GPL(nfs_put_client);
284
285/*
286 * Find an nfs_client on the list that matches the initialisation data
287 * that is supplied.
288 */
289static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
290{
291 struct nfs_client *clp;
292 const struct sockaddr *sap = (struct sockaddr *)data->addr;
293 struct nfs_net *nn = net_generic(net: data->net, id: nfs_net_id);
294 int error;
295
296again:
297 list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
298 const struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
299 /* Don't match clients that failed to initialise properly */
300 if (clp->cl_cons_state < 0)
301 continue;
302
303 /* If a client is still initializing then we need to wait */
304 if (clp->cl_cons_state > NFS_CS_READY) {
305 refcount_inc(r: &clp->cl_count);
306 spin_unlock(lock: &nn->nfs_client_lock);
307 error = nfs_wait_client_init_complete(clp);
308 nfs_put_client(clp);
309 spin_lock(lock: &nn->nfs_client_lock);
310 if (error < 0)
311 return ERR_PTR(error);
312 goto again;
313 }
314
315 /* Different NFS versions cannot share the same nfs_client */
316 if (clp->rpc_ops != data->nfs_mod->rpc_ops)
317 continue;
318
319 if (clp->cl_proto != data->proto)
320 continue;
321 /* Match nfsv4 minorversion */
322 if (clp->cl_minorversion != data->minorversion)
323 continue;
324
325 /* Match request for a dedicated DS */
326 if (test_bit(NFS_CS_DS, &data->init_flags) !=
327 test_bit(NFS_CS_DS, &clp->cl_flags))
328 continue;
329
330 /* Match the full socket address */
331 if (!rpc_cmp_addr_port(sap1: sap, sap2: clap))
332 /* Match all xprt_switch full socket addresses */
333 if (IS_ERR(ptr: clp->cl_rpcclient) ||
334 !rpc_clnt_xprt_switch_has_addr(clnt: clp->cl_rpcclient,
335 sap))
336 continue;
337
338 /* Match the xprt security policy */
339 if (clp->cl_xprtsec.policy != data->xprtsec.policy)
340 continue;
341 if (clp->cl_xprtsec.policy == RPC_XPRTSEC_TLS_X509) {
342 if (clp->cl_xprtsec.cert_serial !=
343 data->xprtsec.cert_serial)
344 continue;
345 if (clp->cl_xprtsec.privkey_serial !=
346 data->xprtsec.privkey_serial)
347 continue;
348 }
349
350 refcount_inc(r: &clp->cl_count);
351 return clp;
352 }
353 return NULL;
354}
355
356/*
357 * Return true if @clp is done initializing, false if still working on it.
358 *
359 * Use nfs_client_init_status to check if it was successful.
360 */
361bool nfs_client_init_is_complete(const struct nfs_client *clp)
362{
363 return clp->cl_cons_state <= NFS_CS_READY;
364}
365EXPORT_SYMBOL_GPL(nfs_client_init_is_complete);
366
367/*
368 * Return 0 if @clp was successfully initialized, -errno otherwise.
369 *
370 * This must be called *after* nfs_client_init_is_complete() returns true,
371 * otherwise it will pop WARN_ON_ONCE and return -EINVAL
372 */
373int nfs_client_init_status(const struct nfs_client *clp)
374{
375 /* called without checking nfs_client_init_is_complete */
376 if (clp->cl_cons_state > NFS_CS_READY) {
377 WARN_ON_ONCE(1);
378 return -EINVAL;
379 }
380 return clp->cl_cons_state;
381}
382EXPORT_SYMBOL_GPL(nfs_client_init_status);
383
384int nfs_wait_client_init_complete(const struct nfs_client *clp)
385{
386 return wait_event_killable(nfs_client_active_wq,
387 nfs_client_init_is_complete(clp));
388}
389EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
390
391/*
392 * Found an existing client. Make sure it's ready before returning.
393 */
394static struct nfs_client *
395nfs_found_client(const struct nfs_client_initdata *cl_init,
396 struct nfs_client *clp)
397{
398 int error;
399
400 error = nfs_wait_client_init_complete(clp);
401 if (error < 0) {
402 nfs_put_client(clp);
403 return ERR_PTR(error: -ERESTARTSYS);
404 }
405
406 if (clp->cl_cons_state < NFS_CS_READY) {
407 error = clp->cl_cons_state;
408 nfs_put_client(clp);
409 return ERR_PTR(error);
410 }
411
412 smp_rmb();
413 return clp;
414}
415
416/*
417 * Look up a client by IP address and protocol version
418 * - creates a new record if one doesn't yet exist
419 */
420struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
421{
422 struct nfs_client *clp, *new = NULL;
423 struct nfs_net *nn = net_generic(net: cl_init->net, id: nfs_net_id);
424 const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
425
426 if (cl_init->hostname == NULL) {
427 WARN_ON(1);
428 return ERR_PTR(error: -EINVAL);
429 }
430
431 /* see if the client already exists */
432 do {
433 spin_lock(lock: &nn->nfs_client_lock);
434
435 clp = nfs_match_client(data: cl_init);
436 if (clp) {
437 spin_unlock(lock: &nn->nfs_client_lock);
438 if (new)
439 new->rpc_ops->free_client(new);
440 if (IS_ERR(ptr: clp))
441 return clp;
442 return nfs_found_client(cl_init, clp);
443 }
444 if (new) {
445 list_add_tail(new: &new->cl_share_link,
446 head: &nn->nfs_client_list);
447 spin_unlock(lock: &nn->nfs_client_lock);
448 new = rpc_ops->init_client(new, cl_init);
449 if (!IS_ERR(ptr: new))
450 nfs_local_probe_async(new);
451 return new;
452 }
453
454 spin_unlock(lock: &nn->nfs_client_lock);
455
456 new = rpc_ops->alloc_client(cl_init);
457 } while (!IS_ERR(ptr: new));
458
459 return new;
460}
461EXPORT_SYMBOL_GPL(nfs_get_client);
462
463/*
464 * Mark a server as ready or failed
465 */
466void nfs_mark_client_ready(struct nfs_client *clp, int state)
467{
468 smp_wmb();
469 clp->cl_cons_state = state;
470 wake_up_all(&nfs_client_active_wq);
471}
472EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
473
474/*
475 * Initialise the timeout values for a connection
476 */
477void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
478 int timeo, int retrans)
479{
480 to->to_initval = timeo * HZ / 10;
481 to->to_retries = retrans;
482
483 switch (proto) {
484 case XPRT_TRANSPORT_TCP:
485 case XPRT_TRANSPORT_TCP_TLS:
486 case XPRT_TRANSPORT_RDMA:
487 if (retrans == NFS_UNSPEC_RETRANS)
488 to->to_retries = NFS_DEF_TCP_RETRANS;
489 if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
490 to->to_initval = NFS_DEF_TCP_TIMEO * HZ / 10;
491 if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
492 to->to_initval = NFS_MAX_TCP_TIMEOUT;
493 to->to_increment = to->to_initval;
494 to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
495 if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
496 to->to_maxval = NFS_MAX_TCP_TIMEOUT;
497 if (to->to_maxval < to->to_initval)
498 to->to_maxval = to->to_initval;
499 to->to_exponential = 0;
500 break;
501 case XPRT_TRANSPORT_UDP:
502 if (retrans == NFS_UNSPEC_RETRANS)
503 to->to_retries = NFS_DEF_UDP_RETRANS;
504 if (timeo == NFS_UNSPEC_TIMEO || to->to_initval == 0)
505 to->to_initval = NFS_DEF_UDP_TIMEO * HZ / 10;
506 if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
507 to->to_initval = NFS_MAX_UDP_TIMEOUT;
508 to->to_maxval = NFS_MAX_UDP_TIMEOUT;
509 to->to_exponential = 1;
510 break;
511 default:
512 BUG();
513 }
514}
515EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
516
517/*
518 * Create an RPC client handle
519 */
520int nfs_create_rpc_client(struct nfs_client *clp,
521 const struct nfs_client_initdata *cl_init,
522 rpc_authflavor_t flavor)
523{
524 struct nfs_net *nn = net_generic(net: clp->cl_net, id: nfs_net_id);
525 struct rpc_clnt *clnt = NULL;
526 struct rpc_create_args args = {
527 .net = clp->cl_net,
528 .protocol = clp->cl_proto,
529 .nconnect = clp->cl_nconnect,
530 .address = (struct sockaddr *)&clp->cl_addr,
531 .addrsize = clp->cl_addrlen,
532 .timeout = cl_init->timeparms,
533 .servername = clp->cl_hostname,
534 .nodename = cl_init->nodename,
535 .program = &nfs_program,
536 .stats = &nn->rpcstats,
537 .version = clp->rpc_ops->version,
538 .authflavor = flavor,
539 .cred = cl_init->cred,
540 .xprtsec = cl_init->xprtsec,
541 .connect_timeout = cl_init->connect_timeout,
542 .reconnect_timeout = cl_init->reconnect_timeout,
543 };
544
545 if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
546 args.flags |= RPC_CLNT_CREATE_DISCRTRY;
547 if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
548 args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
549 if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
550 args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
551 if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
552 args.flags |= RPC_CLNT_CREATE_INFINITE_SLOTS;
553 if (test_bit(NFS_CS_NOPING, &clp->cl_flags))
554 args.flags |= RPC_CLNT_CREATE_NOPING;
555 if (test_bit(NFS_CS_REUSEPORT, &clp->cl_flags))
556 args.flags |= RPC_CLNT_CREATE_REUSEPORT;
557 if (test_bit(NFS_CS_NETUNREACH_FATAL, &clp->cl_flags))
558 args.flags |= RPC_CLNT_CREATE_NETUNREACH_FATAL;
559
560 if (!IS_ERR(ptr: clp->cl_rpcclient))
561 return 0;
562
563 clnt = rpc_create(args: &args);
564 if (IS_ERR(ptr: clnt)) {
565 dprintk("%s: cannot create RPC client. Error = %ld\n",
566 __func__, PTR_ERR(clnt));
567 return PTR_ERR(ptr: clnt);
568 }
569
570 clnt->cl_principal = clp->cl_principal;
571 clp->cl_rpcclient = clnt;
572 clnt->cl_max_connect = clp->cl_max_connect;
573 return 0;
574}
575EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
576
577/*
578 * Version 2 or 3 client destruction
579 */
580static void nfs_destroy_server(struct nfs_server *server)
581{
582 if (server->nlm_host)
583 nlmclnt_done(host: server->nlm_host);
584}
585
586/*
587 * Version 2 or 3 lockd setup
588 */
589static int nfs_start_lockd(struct nfs_server *server)
590{
591 struct nlm_host *host;
592 struct nfs_client *clp = server->nfs_client;
593 struct nlmclnt_initdata nlm_init = {
594 .hostname = clp->cl_hostname,
595 .address = (struct sockaddr *)&clp->cl_addr,
596 .addrlen = clp->cl_addrlen,
597 .nfs_version = clp->rpc_ops->version,
598 .noresvport = server->flags & NFS_MOUNT_NORESVPORT ?
599 1 : 0,
600 .net = clp->cl_net,
601 .nlmclnt_ops = clp->cl_nfs_mod->rpc_ops->nlmclnt_ops,
602 .cred = server->cred,
603 };
604
605 if (nlm_init.nfs_version > 3)
606 return 0;
607 if ((server->flags & NFS_MOUNT_LOCAL_FLOCK) &&
608 (server->flags & NFS_MOUNT_LOCAL_FCNTL))
609 return 0;
610
611 switch (clp->cl_proto) {
612 default:
613 nlm_init.protocol = IPPROTO_TCP;
614 break;
615#ifndef CONFIG_NFS_DISABLE_UDP_SUPPORT
616 case XPRT_TRANSPORT_UDP:
617 nlm_init.protocol = IPPROTO_UDP;
618#endif
619 }
620
621 host = nlmclnt_init(nlm_init: &nlm_init);
622 if (IS_ERR(ptr: host))
623 return PTR_ERR(ptr: host);
624
625 server->nlm_host = host;
626 server->destroy = nfs_destroy_server;
627 nfs_sysfs_link_rpc_client(server, clnt: nlmclnt_rpc_clnt(host), NULL);
628 return 0;
629}
630
631/*
632 * Create a general RPC client
633 */
634int nfs_init_server_rpcclient(struct nfs_server *server,
635 const struct rpc_timeout *timeo,
636 rpc_authflavor_t pseudoflavour)
637{
638 struct nfs_client *clp = server->nfs_client;
639
640 server->client = rpc_clone_client_set_auth(clp->cl_rpcclient,
641 pseudoflavour);
642 if (IS_ERR(ptr: server->client)) {
643 dprintk("%s: couldn't create rpc_client!\n", __func__);
644 return PTR_ERR(ptr: server->client);
645 }
646
647 memcpy(&server->client->cl_timeout_default,
648 timeo,
649 sizeof(server->client->cl_timeout_default));
650 server->client->cl_timeout = &server->client->cl_timeout_default;
651 server->client->cl_softrtry = 0;
652 if (server->flags & NFS_MOUNT_SOFTERR)
653 server->client->cl_softerr = 1;
654 if (server->flags & NFS_MOUNT_SOFT)
655 server->client->cl_softrtry = 1;
656
657 nfs_sysfs_link_rpc_client(server, clnt: server->client, NULL);
658 return 0;
659}
660EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
661
662/**
663 * nfs_init_client - Initialise an NFS2 or NFS3 client
664 *
665 * @clp: nfs_client to initialise
666 * @cl_init: Initialisation parameters
667 *
668 * Returns pointer to an NFS client, or an ERR_PTR value.
669 */
670struct nfs_client *nfs_init_client(struct nfs_client *clp,
671 const struct nfs_client_initdata *cl_init)
672{
673 int error;
674
675 /* the client is already initialised */
676 if (clp->cl_cons_state == NFS_CS_READY)
677 return clp;
678
679 /*
680 * Create a client RPC handle for doing FSSTAT with UNIX auth only
681 * - RFC 2623, sec 2.3.2
682 */
683 error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
684 nfs_mark_client_ready(clp, error == 0 ? NFS_CS_READY : error);
685 if (error < 0) {
686 nfs_put_client(clp);
687 clp = ERR_PTR(error);
688 }
689 return clp;
690}
691EXPORT_SYMBOL_GPL(nfs_init_client);
692
693static void nfs4_server_set_init_caps(struct nfs_server *server)
694{
695#if IS_ENABLED(CONFIG_NFS_V4)
696 /* Set the basic capabilities */
697 server->caps = server->nfs_client->cl_mvops->init_caps;
698 if (server->flags & NFS_MOUNT_NORDIRPLUS)
699 server->caps &= ~NFS_CAP_READDIRPLUS;
700 if (server->nfs_client->cl_proto == XPRT_TRANSPORT_RDMA)
701 server->caps &= ~NFS_CAP_READ_PLUS;
702
703 /*
704 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
705 * authentication.
706 */
707 if (nfs4_disable_idmapping &&
708 server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
709 server->caps |= NFS_CAP_UIDGID_NOMAP;
710#endif
711}
712
713void nfs_server_set_init_caps(struct nfs_server *server)
714{
715 switch (server->nfs_client->rpc_ops->version) {
716 case 2:
717 server->caps = NFS_CAP_HARDLINKS | NFS_CAP_SYMLINKS;
718 break;
719 case 3:
720 server->caps = NFS_CAP_HARDLINKS | NFS_CAP_SYMLINKS;
721 if (!(server->flags & NFS_MOUNT_NORDIRPLUS))
722 server->caps |= NFS_CAP_READDIRPLUS;
723 break;
724 default:
725 nfs4_server_set_init_caps(server);
726 break;
727 }
728}
729EXPORT_SYMBOL_GPL(nfs_server_set_init_caps);
730
731/*
732 * Create a version 2 or 3 client
733 */
734static int nfs_init_server(struct nfs_server *server,
735 const struct fs_context *fc)
736{
737 const struct nfs_fs_context *ctx = nfs_fc2context(fc);
738 struct rpc_timeout timeparms;
739 struct nfs_client_initdata cl_init = {
740 .hostname = ctx->nfs_server.hostname,
741 .addr = &ctx->nfs_server._address,
742 .addrlen = ctx->nfs_server.addrlen,
743 .nfs_mod = ctx->nfs_mod,
744 .proto = ctx->nfs_server.protocol,
745 .net = fc->net_ns,
746 .timeparms = &timeparms,
747 .cred = server->cred,
748 .nconnect = ctx->nfs_server.nconnect,
749 .init_flags = (1UL << NFS_CS_REUSEPORT),
750 .xprtsec = ctx->xprtsec,
751 };
752 struct nfs_client *clp;
753 int error;
754
755 nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
756 ctx->timeo, ctx->retrans);
757 if (ctx->flags & NFS_MOUNT_NORESVPORT)
758 set_bit(NFS_CS_NORESVPORT, addr: &cl_init.init_flags);
759
760 if (ctx->flags & NFS_MOUNT_NETUNREACH_FATAL)
761 __set_bit(NFS_CS_NETUNREACH_FATAL, &cl_init.init_flags);
762
763 /* Allocate or find a client reference we can use */
764 clp = nfs_get_client(&cl_init);
765 if (IS_ERR(ptr: clp))
766 return PTR_ERR(ptr: clp);
767
768 server->nfs_client = clp;
769 nfs_sysfs_add_server(s: server);
770 nfs_sysfs_link_rpc_client(server, clnt: clp->cl_rpcclient, sysfs_prefix: "_state");
771
772 /* Initialise the client representation from the mount data */
773 server->flags = ctx->flags;
774 server->options = ctx->options;
775
776 switch (clp->rpc_ops->version) {
777 case 2:
778 server->fattr_valid = NFS_ATTR_FATTR_V2;
779 break;
780 case 3:
781 server->fattr_valid = NFS_ATTR_FATTR_V3;
782 break;
783 default:
784 server->fattr_valid = NFS_ATTR_FATTR_V4;
785 }
786
787 if (ctx->bsize) {
788 server->bsize = ctx->bsize;
789 server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_BSIZE;
790 }
791 if (ctx->rsize) {
792 server->rsize = nfs_io_size(iosize: ctx->rsize, proto: clp->cl_proto);
793 server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_RSIZE;
794 }
795 if (ctx->wsize) {
796 server->wsize = nfs_io_size(iosize: ctx->wsize, proto: clp->cl_proto);
797 server->automount_inherit |= NFS_AUTOMOUNT_INHERIT_WSIZE;
798 }
799
800 server->acregmin = ctx->acregmin * HZ;
801 server->acregmax = ctx->acregmax * HZ;
802 server->acdirmin = ctx->acdirmin * HZ;
803 server->acdirmax = ctx->acdirmax * HZ;
804
805 /* Start lockd here, before we might error out */
806 error = nfs_start_lockd(server);
807 if (error < 0)
808 goto error;
809
810 server->port = ctx->nfs_server.port;
811 server->auth_info = ctx->auth_info;
812
813 error = nfs_init_server_rpcclient(server, &timeparms,
814 ctx->selected_flavor);
815 if (error < 0)
816 goto error;
817
818 nfs_server_set_init_caps(server);
819
820 /* Preserve the values of mount_server-related mount options */
821 if (ctx->mount_server.addrlen) {
822 memcpy(&server->mountd_address, &ctx->mount_server.address,
823 ctx->mount_server.addrlen);
824 server->mountd_addrlen = ctx->mount_server.addrlen;
825 }
826 server->mountd_version = ctx->mount_server.version;
827 server->mountd_port = ctx->mount_server.port;
828 server->mountd_protocol = ctx->mount_server.protocol;
829
830 server->namelen = ctx->namlen;
831 return 0;
832
833error:
834 server->nfs_client = NULL;
835 nfs_put_client(clp);
836 return error;
837}
838
839/*
840 * Load up the server record from information gained in an fsinfo record
841 */
842static void nfs_server_set_fsinfo(struct nfs_server *server,
843 struct nfs_fsinfo *fsinfo)
844{
845 struct nfs_client *clp = server->nfs_client;
846 unsigned long max_rpc_payload, raw_max_rpc_payload;
847
848 /* Work out a lot of parameters */
849 if (server->rsize == 0)
850 server->rsize = nfs_io_size(iosize: fsinfo->rtpref, proto: clp->cl_proto);
851 if (server->wsize == 0)
852 server->wsize = nfs_io_size(iosize: fsinfo->wtpref, proto: clp->cl_proto);
853
854 if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
855 server->rsize = nfs_io_size(iosize: fsinfo->rtmax, proto: clp->cl_proto);
856 if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
857 server->wsize = nfs_io_size(iosize: fsinfo->wtmax, proto: clp->cl_proto);
858
859 raw_max_rpc_payload = rpc_max_payload(server->client);
860 max_rpc_payload = nfs_block_size(bsize: raw_max_rpc_payload, NULL);
861
862 if (server->rsize > max_rpc_payload)
863 server->rsize = max_rpc_payload;
864 if (server->rsize > NFS_MAX_FILE_IO_SIZE)
865 server->rsize = NFS_MAX_FILE_IO_SIZE;
866 server->rpages = (server->rsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
867
868 if (server->wsize > max_rpc_payload)
869 server->wsize = max_rpc_payload;
870 if (server->wsize > NFS_MAX_FILE_IO_SIZE)
871 server->wsize = NFS_MAX_FILE_IO_SIZE;
872
873 server->wtmult = nfs_block_bits(bsize: fsinfo->wtmult, NULL);
874
875 server->dtsize = nfs_block_size(bsize: fsinfo->dtpref, NULL);
876 if (server->dtsize > NFS_MAX_FILE_IO_SIZE)
877 server->dtsize = NFS_MAX_FILE_IO_SIZE;
878 if (server->dtsize > server->rsize)
879 server->dtsize = server->rsize;
880
881 if (server->flags & NFS_MOUNT_NOAC) {
882 server->acregmin = server->acregmax = 0;
883 server->acdirmin = server->acdirmax = 0;
884 }
885
886 server->maxfilesize = fsinfo->maxfilesize;
887
888 server->change_attr_type = fsinfo->change_attr_type;
889
890 server->clone_blksize = fsinfo->clone_blksize;
891 /* We're airborne Set socket buffersize */
892 rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
893
894#ifdef CONFIG_NFS_V4_2
895 /*
896 * Defaults until limited by the session parameters.
897 */
898 server->gxasize = min_t(unsigned int, raw_max_rpc_payload,
899 XATTR_SIZE_MAX);
900 server->sxasize = min_t(unsigned int, raw_max_rpc_payload,
901 XATTR_SIZE_MAX);
902 server->lxasize = min_t(unsigned int, raw_max_rpc_payload,
903 nfs42_listxattr_xdrsize(XATTR_LIST_MAX));
904
905 if (fsinfo->xattr_support)
906 server->caps |= NFS_CAP_XATTR;
907 else
908 server->caps &= ~NFS_CAP_XATTR;
909#endif
910}
911
912/*
913 * Probe filesystem information, including the FSID on v2/v3
914 */
915static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
916{
917 struct nfs_fsinfo fsinfo;
918 struct nfs_client *clp = server->nfs_client;
919 int error;
920
921 if (clp->rpc_ops->set_capabilities != NULL) {
922 error = clp->rpc_ops->set_capabilities(server, mntfh);
923 if (error < 0)
924 return error;
925 }
926
927 fsinfo.fattr = fattr;
928 fsinfo.nlayouttypes = 0;
929 memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
930 error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
931 if (error < 0)
932 return error;
933
934 nfs_server_set_fsinfo(server, fsinfo: &fsinfo);
935
936 /* Get some general file system info */
937 if (server->namelen == 0) {
938 struct nfs_pathconf pathinfo;
939
940 pathinfo.fattr = fattr;
941 nfs_fattr_init(fattr);
942
943 if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
944 server->namelen = pathinfo.max_namelen;
945 }
946
947 if (clp->rpc_ops->discover_trunking != NULL &&
948 (server->caps & NFS_CAP_FS_LOCATIONS &&
949 (server->flags & NFS_MOUNT_TRUNK_DISCOVERY))) {
950 error = clp->rpc_ops->discover_trunking(server, mntfh);
951 if (error < 0)
952 return error;
953 }
954
955 return 0;
956}
957
958/*
959 * Grab the destination's particulars, including lease expiry time.
960 *
961 * Returns zero if probe succeeded and retrieved FSID matches the FSID
962 * we have cached.
963 */
964int nfs_probe_server(struct nfs_server *server, struct nfs_fh *mntfh)
965{
966 struct nfs_fattr *fattr;
967 int error;
968
969 fattr = nfs_alloc_fattr();
970 if (fattr == NULL)
971 return -ENOMEM;
972
973 /* Sanity: the probe won't work if the destination server
974 * does not recognize the migrated FH. */
975 error = nfs_probe_fsinfo(server, mntfh, fattr);
976
977 nfs_free_fattr(fattr);
978 return error;
979}
980EXPORT_SYMBOL_GPL(nfs_probe_server);
981
982/*
983 * Copy useful information when duplicating a server record
984 */
985void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
986{
987 target->flags = source->flags;
988 target->automount_inherit = source->automount_inherit;
989 if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_BSIZE)
990 target->bsize = source->bsize;
991 if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_RSIZE)
992 target->rsize = source->rsize;
993 if (source->automount_inherit & NFS_AUTOMOUNT_INHERIT_WSIZE)
994 target->wsize = source->wsize;
995 target->acregmin = source->acregmin;
996 target->acregmax = source->acregmax;
997 target->acdirmin = source->acdirmin;
998 target->acdirmax = source->acdirmax;
999 target->options = source->options;
1000 target->auth_info = source->auth_info;
1001 target->port = source->port;
1002}
1003EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
1004
1005void nfs_server_insert_lists(struct nfs_server *server)
1006{
1007 struct nfs_client *clp = server->nfs_client;
1008 struct nfs_net *nn = net_generic(net: clp->cl_net, id: nfs_net_id);
1009
1010 spin_lock(lock: &nn->nfs_client_lock);
1011 list_add_tail_rcu(new: &server->client_link, head: &clp->cl_superblocks);
1012 list_add_tail(new: &server->master_link, head: &nn->nfs_volume_list);
1013 clear_bit(NFS_CS_STOP_RENEW, addr: &clp->cl_res_state);
1014 spin_unlock(lock: &nn->nfs_client_lock);
1015
1016}
1017EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
1018
1019void nfs_server_remove_lists(struct nfs_server *server)
1020{
1021 struct nfs_client *clp = server->nfs_client;
1022 struct nfs_net *nn;
1023
1024 if (clp == NULL)
1025 return;
1026 nn = net_generic(net: clp->cl_net, id: nfs_net_id);
1027 spin_lock(lock: &nn->nfs_client_lock);
1028 list_del_rcu(entry: &server->client_link);
1029 if (list_empty(head: &clp->cl_superblocks))
1030 set_bit(NFS_CS_STOP_RENEW, addr: &clp->cl_res_state);
1031 list_del(entry: &server->master_link);
1032 spin_unlock(lock: &nn->nfs_client_lock);
1033
1034 synchronize_rcu();
1035}
1036EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
1037
1038static DEFINE_IDA(s_sysfs_ids);
1039
1040/*
1041 * Allocate and initialise a server record
1042 */
1043struct nfs_server *nfs_alloc_server(void)
1044{
1045 struct nfs_server *server;
1046
1047 server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
1048 if (!server)
1049 return NULL;
1050
1051 server->s_sysfs_id = ida_alloc(ida: &s_sysfs_ids, GFP_KERNEL);
1052 if (server->s_sysfs_id < 0) {
1053 kfree(objp: server);
1054 return NULL;
1055 }
1056
1057 server->client = server->client_acl = ERR_PTR(error: -EINVAL);
1058
1059 /* Zero out the NFS state stuff */
1060 INIT_LIST_HEAD(list: &server->client_link);
1061 INIT_LIST_HEAD(list: &server->master_link);
1062 INIT_LIST_HEAD(list: &server->delegations);
1063 INIT_LIST_HEAD(list: &server->layouts);
1064 INIT_LIST_HEAD(list: &server->state_owners_lru);
1065 INIT_LIST_HEAD(list: &server->ss_copies);
1066 INIT_LIST_HEAD(list: &server->ss_src_copies);
1067
1068 atomic_set(v: &server->active, i: 0);
1069 atomic_long_set(v: &server->nr_active_delegations, i: 0);
1070
1071 server->io_stats = nfs_alloc_iostats();
1072 if (!server->io_stats) {
1073 kfree(objp: server);
1074 return NULL;
1075 }
1076
1077 server->change_attr_type = NFS4_CHANGE_TYPE_IS_UNDEFINED;
1078
1079 init_waitqueue_head(&server->write_congestion_wait);
1080 atomic_long_set(v: &server->writeback, i: 0);
1081
1082 atomic64_set(v: &server->owner_ctr, i: 0);
1083
1084 pnfs_init_server(server);
1085 rpc_init_wait_queue(&server->uoc_rpcwaitq, "NFS UOC");
1086
1087 return server;
1088}
1089EXPORT_SYMBOL_GPL(nfs_alloc_server);
1090
1091static void delayed_free(struct rcu_head *p)
1092{
1093 struct nfs_server *server = container_of(p, struct nfs_server, rcu);
1094
1095 nfs_free_iostats(stats: server->io_stats);
1096 kfree(objp: server);
1097}
1098
1099/*
1100 * Free up a server record
1101 */
1102void nfs_free_server(struct nfs_server *server)
1103{
1104 nfs_server_remove_lists(server);
1105
1106 if (server->destroy != NULL)
1107 server->destroy(server);
1108
1109 if (!IS_ERR(ptr: server->client_acl))
1110 rpc_shutdown_client(server->client_acl);
1111 if (!IS_ERR(ptr: server->client))
1112 rpc_shutdown_client(server->client);
1113
1114 nfs_put_client(server->nfs_client);
1115
1116 if (server->kobj.state_initialized) {
1117 nfs_sysfs_remove_server(s: server);
1118 kobject_put(kobj: &server->kobj);
1119 }
1120 ida_free(&s_sysfs_ids, id: server->s_sysfs_id);
1121
1122 put_cred(cred: server->cred);
1123 nfs_release_automount_timer();
1124 call_rcu(head: &server->rcu, func: delayed_free);
1125}
1126EXPORT_SYMBOL_GPL(nfs_free_server);
1127
1128/*
1129 * Create a version 2 or 3 volume record
1130 * - keyed on server and FSID
1131 */
1132struct nfs_server *nfs_create_server(struct fs_context *fc)
1133{
1134 struct nfs_fs_context *ctx = nfs_fc2context(fc);
1135 struct nfs_server *server;
1136 struct nfs_fattr *fattr;
1137 int error;
1138
1139 server = nfs_alloc_server();
1140 if (!server)
1141 return ERR_PTR(error: -ENOMEM);
1142
1143 server->cred = get_cred(cred: fc->cred);
1144
1145 error = -ENOMEM;
1146 fattr = nfs_alloc_fattr();
1147 if (fattr == NULL)
1148 goto error;
1149
1150 /* Get a client representation */
1151 error = nfs_init_server(server, fc);
1152 if (error < 0)
1153 goto error;
1154
1155 /* Probe the root fh to retrieve its FSID */
1156 error = nfs_probe_fsinfo(server, mntfh: ctx->mntfh, fattr);
1157 if (error < 0)
1158 goto error;
1159 if (server->nfs_client->rpc_ops->version == 3) {
1160 if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
1161 server->namelen = NFS3_MAXNAMLEN;
1162 if (!(ctx->flags & NFS_MOUNT_NORDIRPLUS))
1163 server->caps |= NFS_CAP_READDIRPLUS;
1164 } else {
1165 if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
1166 server->namelen = NFS2_MAXNAMLEN;
1167 }
1168 /* Linux 'subtree_check' borkenness mandates this setting */
1169 server->fh_expire_type = NFS_FH_VOL_RENAME;
1170
1171 if (!(fattr->valid & NFS_ATTR_FATTR)) {
1172 error = ctx->nfs_mod->rpc_ops->getattr(server, ctx->mntfh,
1173 fattr, NULL);
1174 if (error < 0) {
1175 dprintk("nfs_create_server: getattr error = %d\n", -error);
1176 goto error;
1177 }
1178 }
1179 memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
1180
1181 dprintk("Server FSID: %llx:%llx\n",
1182 (unsigned long long) server->fsid.major,
1183 (unsigned long long) server->fsid.minor);
1184
1185 nfs_server_insert_lists(server);
1186 server->mount_time = jiffies;
1187 nfs_free_fattr(fattr);
1188 return server;
1189
1190error:
1191 nfs_free_fattr(fattr);
1192 nfs_free_server(server);
1193 return ERR_PTR(error);
1194}
1195EXPORT_SYMBOL_GPL(nfs_create_server);
1196
1197/*
1198 * Clone an NFS2, NFS3 or NFS4 server record
1199 */
1200struct nfs_server *nfs_clone_server(struct nfs_server *source,
1201 struct nfs_fh *fh,
1202 struct nfs_fattr *fattr,
1203 rpc_authflavor_t flavor)
1204{
1205 struct nfs_server *server;
1206 int error;
1207
1208 server = nfs_alloc_server();
1209 if (!server)
1210 return ERR_PTR(error: -ENOMEM);
1211
1212 server->cred = get_cred(cred: source->cred);
1213
1214 /* Copy data from the source */
1215 server->nfs_client = source->nfs_client;
1216 server->destroy = source->destroy;
1217 refcount_inc(r: &server->nfs_client->cl_count);
1218 nfs_server_copy_userdata(server, source);
1219
1220 server->fsid = fattr->fsid;
1221
1222 nfs_sysfs_add_server(s: server);
1223
1224 nfs_sysfs_link_rpc_client(server,
1225 clnt: server->nfs_client->cl_rpcclient, sysfs_prefix: "_state");
1226
1227 error = nfs_init_server_rpcclient(server,
1228 source->client->cl_timeout,
1229 flavor);
1230 if (error < 0)
1231 goto out_free_server;
1232
1233 nfs_server_set_init_caps(server);
1234
1235 /* probe the filesystem info for this server filesystem */
1236 error = nfs_probe_server(server, fh);
1237 if (error < 0)
1238 goto out_free_server;
1239
1240 if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1241 server->namelen = NFS4_MAXNAMLEN;
1242
1243 error = nfs_start_lockd(server);
1244 if (error < 0)
1245 goto out_free_server;
1246
1247 nfs_server_insert_lists(server);
1248 server->mount_time = jiffies;
1249
1250 return server;
1251
1252out_free_server:
1253 nfs_free_server(server);
1254 return ERR_PTR(error);
1255}
1256EXPORT_SYMBOL_GPL(nfs_clone_server);
1257
1258void nfs_clients_init(struct net *net)
1259{
1260 struct nfs_net *nn = net_generic(net, id: nfs_net_id);
1261
1262 INIT_LIST_HEAD(list: &nn->nfs_client_list);
1263 INIT_LIST_HEAD(list: &nn->nfs_volume_list);
1264#if IS_ENABLED(CONFIG_NFS_V4)
1265 idr_init(idr: &nn->cb_ident_idr);
1266#endif
1267#if IS_ENABLED(CONFIG_NFS_V4_1)
1268 INIT_LIST_HEAD(list: &nn->nfs4_data_server_cache);
1269 spin_lock_init(&nn->nfs4_data_server_lock);
1270#endif
1271 spin_lock_init(&nn->nfs_client_lock);
1272 nn->boot_time = ktime_get_real();
1273 memset(&nn->rpcstats, 0, sizeof(nn->rpcstats));
1274 nn->rpcstats.program = &nfs_program;
1275
1276 nfs_netns_sysfs_setup(netns: nn, net);
1277}
1278
1279void nfs_clients_exit(struct net *net)
1280{
1281 struct nfs_net *nn = net_generic(net, id: nfs_net_id);
1282
1283 nfs_netns_sysfs_destroy(netns: nn);
1284 nfs_cleanup_cb_ident_idr(net);
1285 WARN_ON_ONCE(!list_empty(&nn->nfs_client_list));
1286 WARN_ON_ONCE(!list_empty(&nn->nfs_volume_list));
1287#if IS_ENABLED(CONFIG_NFS_V4_1)
1288 WARN_ON_ONCE(!list_empty(&nn->nfs4_data_server_cache));
1289#endif
1290}
1291
1292#ifdef CONFIG_PROC_FS
1293static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1294static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1295static void nfs_server_list_stop(struct seq_file *p, void *v);
1296static int nfs_server_list_show(struct seq_file *m, void *v);
1297
1298static const struct seq_operations nfs_server_list_ops = {
1299 .start = nfs_server_list_start,
1300 .next = nfs_server_list_next,
1301 .stop = nfs_server_list_stop,
1302 .show = nfs_server_list_show,
1303};
1304
1305static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1306static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1307static void nfs_volume_list_stop(struct seq_file *p, void *v);
1308static int nfs_volume_list_show(struct seq_file *m, void *v);
1309
1310static const struct seq_operations nfs_volume_list_ops = {
1311 .start = nfs_volume_list_start,
1312 .next = nfs_volume_list_next,
1313 .stop = nfs_volume_list_stop,
1314 .show = nfs_volume_list_show,
1315};
1316
1317/*
1318 * set up the iterator to start reading from the server list and return the first item
1319 */
1320static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1321 __acquires(&nn->nfs_client_lock)
1322{
1323 struct nfs_net *nn = net_generic(net: seq_file_net(seq: m), id: nfs_net_id);
1324
1325 /* lock the list against modification */
1326 spin_lock(lock: &nn->nfs_client_lock);
1327 return seq_list_start_head(head: &nn->nfs_client_list, pos: *_pos);
1328}
1329
1330/*
1331 * move to next server
1332 */
1333static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1334{
1335 struct nfs_net *nn = net_generic(net: seq_file_net(seq: p), id: nfs_net_id);
1336
1337 return seq_list_next(v, head: &nn->nfs_client_list, ppos: pos);
1338}
1339
1340/*
1341 * clean up after reading from the transports list
1342 */
1343static void nfs_server_list_stop(struct seq_file *p, void *v)
1344 __releases(&nn->nfs_client_lock)
1345{
1346 struct nfs_net *nn = net_generic(net: seq_file_net(seq: p), id: nfs_net_id);
1347
1348 spin_unlock(lock: &nn->nfs_client_lock);
1349}
1350
1351/*
1352 * display a header line followed by a load of call lines
1353 */
1354static int nfs_server_list_show(struct seq_file *m, void *v)
1355{
1356 struct nfs_client *clp;
1357 struct nfs_net *nn = net_generic(net: seq_file_net(seq: m), id: nfs_net_id);
1358
1359 /* display header on line 1 */
1360 if (v == &nn->nfs_client_list) {
1361 seq_puts(m, s: "NV SERVER PORT USE HOSTNAME\n");
1362 return 0;
1363 }
1364
1365 /* display one transport per line on subsequent lines */
1366 clp = list_entry(v, struct nfs_client, cl_share_link);
1367
1368 /* Check if the client is initialized */
1369 if (clp->cl_cons_state != NFS_CS_READY)
1370 return 0;
1371
1372 rcu_read_lock();
1373 seq_printf(m, fmt: "v%u %s %s %3d %s\n",
1374 clp->rpc_ops->version,
1375 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1376 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1377 refcount_read(r: &clp->cl_count),
1378 clp->cl_hostname);
1379 rcu_read_unlock();
1380
1381 return 0;
1382}
1383
1384/*
1385 * set up the iterator to start reading from the volume list and return the first item
1386 */
1387static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1388 __acquires(&nn->nfs_client_lock)
1389{
1390 struct nfs_net *nn = net_generic(net: seq_file_net(seq: m), id: nfs_net_id);
1391
1392 /* lock the list against modification */
1393 spin_lock(lock: &nn->nfs_client_lock);
1394 return seq_list_start_head(head: &nn->nfs_volume_list, pos: *_pos);
1395}
1396
1397/*
1398 * move to next volume
1399 */
1400static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1401{
1402 struct nfs_net *nn = net_generic(net: seq_file_net(seq: p), id: nfs_net_id);
1403
1404 return seq_list_next(v, head: &nn->nfs_volume_list, ppos: pos);
1405}
1406
1407/*
1408 * clean up after reading from the transports list
1409 */
1410static void nfs_volume_list_stop(struct seq_file *p, void *v)
1411 __releases(&nn->nfs_client_lock)
1412{
1413 struct nfs_net *nn = net_generic(net: seq_file_net(seq: p), id: nfs_net_id);
1414
1415 spin_unlock(lock: &nn->nfs_client_lock);
1416}
1417
1418/*
1419 * display a header line followed by a load of call lines
1420 */
1421static int nfs_volume_list_show(struct seq_file *m, void *v)
1422{
1423 struct nfs_server *server;
1424 struct nfs_client *clp;
1425 char dev[13]; // 8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0'
1426 char fsid[34]; // 2 * 16 for %llx, 1 for ':', 1 for '\0'
1427 struct nfs_net *nn = net_generic(net: seq_file_net(seq: m), id: nfs_net_id);
1428
1429 /* display header on line 1 */
1430 if (v == &nn->nfs_volume_list) {
1431 seq_puts(m, s: "NV SERVER PORT DEV FSID"
1432 " FSC\n");
1433 return 0;
1434 }
1435 /* display one transport per line on subsequent lines */
1436 server = list_entry(v, struct nfs_server, master_link);
1437 clp = server->nfs_client;
1438
1439 snprintf(buf: dev, size: sizeof(dev), fmt: "%u:%u",
1440 MAJOR(server->s_dev), MINOR(server->s_dev));
1441
1442 snprintf(buf: fsid, size: sizeof(fsid), fmt: "%llx:%llx",
1443 (unsigned long long) server->fsid.major,
1444 (unsigned long long) server->fsid.minor);
1445
1446 rcu_read_lock();
1447 seq_printf(m, fmt: "v%u %s %s %-12s %-33s %s\n",
1448 clp->rpc_ops->version,
1449 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1450 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1451 dev,
1452 fsid,
1453 nfs_server_fscache_state(server));
1454 rcu_read_unlock();
1455
1456 return 0;
1457}
1458
1459int nfs_fs_proc_net_init(struct net *net)
1460{
1461 struct nfs_net *nn = net_generic(net, id: nfs_net_id);
1462 struct proc_dir_entry *p;
1463
1464 nn->proc_nfsfs = proc_net_mkdir(net, name: "nfsfs", parent: net->proc_net);
1465 if (!nn->proc_nfsfs)
1466 goto error_0;
1467
1468 /* a file of servers with which we're dealing */
1469 p = proc_create_net("servers", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1470 &nfs_server_list_ops, sizeof(struct seq_net_private));
1471 if (!p)
1472 goto error_1;
1473
1474 /* a file of volumes that we have mounted */
1475 p = proc_create_net("volumes", S_IFREG|S_IRUGO, nn->proc_nfsfs,
1476 &nfs_volume_list_ops, sizeof(struct seq_net_private));
1477 if (!p)
1478 goto error_1;
1479 return 0;
1480
1481error_1:
1482 remove_proc_subtree("nfsfs", net->proc_net);
1483error_0:
1484 return -ENOMEM;
1485}
1486
1487void nfs_fs_proc_net_exit(struct net *net)
1488{
1489 remove_proc_subtree("nfsfs", net->proc_net);
1490}
1491
1492/*
1493 * initialise the /proc/fs/nfsfs/ directory
1494 */
1495int __init nfs_fs_proc_init(void)
1496{
1497 if (!proc_mkdir("fs/nfsfs", NULL))
1498 goto error_0;
1499
1500 /* a file of servers with which we're dealing */
1501 if (!proc_symlink("fs/nfsfs/servers", NULL, "../../net/nfsfs/servers"))
1502 goto error_1;
1503
1504 /* a file of volumes that we have mounted */
1505 if (!proc_symlink("fs/nfsfs/volumes", NULL, "../../net/nfsfs/volumes"))
1506 goto error_1;
1507
1508 return 0;
1509error_1:
1510 remove_proc_subtree("fs/nfsfs", NULL);
1511error_0:
1512 return -ENOMEM;
1513}
1514
1515/*
1516 * clean up the /proc/fs/nfsfs/ directory
1517 */
1518void nfs_fs_proc_exit(void)
1519{
1520 remove_proc_subtree("fs/nfsfs", NULL);
1521 ida_destroy(ida: &s_sysfs_ids);
1522}
1523
1524#endif /* CONFIG_PROC_FS */
1525

source code of linux/fs/nfs/client.c