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