1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/fs/nfs/super.c
4 *
5 * Copyright (C) 1992 Rick Sladkey
6 *
7 * nfs superblock handling functions
8 *
9 * Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
10 * experimental NFS changes. Modularisation taken straight from SYS5 fs.
11 *
12 * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
13 * J.S.Peatfield@damtp.cam.ac.uk
14 *
15 * Split from inode.c by David Howells <dhowells@redhat.com>
16 *
17 * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
18 * particular server are held in the same superblock
19 * - NFS superblocks can have several effective roots to the dentry tree
20 * - directory type roots are spliced into the tree when a path from one root reaches the root
21 * of another (see nfs_lookup())
22 */
23
24 #include <linux/module.h>
25 #include <linux/init.h>
26
27 #include <linux/time.h>
28 #include <linux/kernel.h>
29 #include <linux/mm.h>
30 #include <linux/string.h>
31 #include <linux/stat.h>
32 #include <linux/errno.h>
33 #include <linux/unistd.h>
34 #include <linux/sunrpc/clnt.h>
35 #include <linux/sunrpc/addr.h>
36 #include <linux/sunrpc/stats.h>
37 #include <linux/sunrpc/metrics.h>
38 #include <linux/sunrpc/xprtsock.h>
39 #include <linux/sunrpc/xprtrdma.h>
40 #include <linux/nfs_fs.h>
41 #include <linux/nfs_mount.h>
42 #include <linux/nfs4_mount.h>
43 #include <linux/lockd/bind.h>
44 #include <linux/seq_file.h>
45 #include <linux/mount.h>
46 #include <linux/namei.h>
47 #include <linux/vfs.h>
48 #include <linux/inet.h>
49 #include <linux/in6.h>
50 #include <linux/sched.h>
51 #include <linux/slab.h>
52 #include <net/ipv6.h>
53 #include <linux/netdevice.h>
54 #include <linux/nfs_xdr.h>
55 #include <linux/magic.h>
56 #include <linux/parser.h>
57 #include <linux/nsproxy.h>
58 #include <linux/rcupdate.h>
59
60 #include <linux/uaccess.h>
61 #include <linux/nfs_ssc.h>
62
63 #include <uapi/linux/tls.h>
64
65 #include "nfs4_fs.h"
66 #include "callback.h"
67 #include "delegation.h"
68 #include "iostat.h"
69 #include "internal.h"
70 #include "fscache.h"
71 #include "nfs4session.h"
72 #include "pnfs.h"
73 #include "nfs.h"
74 #include "netns.h"
75 #include "sysfs.h"
76
77 #define NFSDBG_FACILITY NFSDBG_VFS
78
79 const struct super_operations nfs_sops = {
80 .alloc_inode = nfs_alloc_inode,
81 .free_inode = nfs_free_inode,
82 .write_inode = nfs_write_inode,
83 .drop_inode = nfs_drop_inode,
84 .statfs = nfs_statfs,
85 .evict_inode = nfs_evict_inode,
86 .umount_begin = nfs_umount_begin,
87 .show_options = nfs_show_options,
88 .show_devname = nfs_show_devname,
89 .show_path = nfs_show_path,
90 .show_stats = nfs_show_stats,
91 };
92 EXPORT_SYMBOL_GPL(nfs_sops);
93
94 #ifdef CONFIG_NFS_V4_2
95 static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = {
96 .sco_sb_deactive = nfs_sb_deactive,
97 };
98 #endif
99
100 #if IS_ENABLED(CONFIG_NFS_V4)
register_nfs4_fs(void)101 static int __init register_nfs4_fs(void)
102 {
103 return register_filesystem(&nfs4_fs_type);
104 }
105
unregister_nfs4_fs(void)106 static void unregister_nfs4_fs(void)
107 {
108 unregister_filesystem(&nfs4_fs_type);
109 }
110 #else
register_nfs4_fs(void)111 static int __init register_nfs4_fs(void)
112 {
113 return 0;
114 }
115
unregister_nfs4_fs(void)116 static void unregister_nfs4_fs(void)
117 {
118 }
119 #endif
120
121 #ifdef CONFIG_NFS_V4_2
nfs_ssc_register_ops(void)122 static void nfs_ssc_register_ops(void)
123 {
124 nfs_ssc_register(&nfs_ssc_clnt_ops_tbl);
125 }
126
nfs_ssc_unregister_ops(void)127 static void nfs_ssc_unregister_ops(void)
128 {
129 nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl);
130 }
131 #endif /* CONFIG_NFS_V4_2 */
132
133 static struct shrinker *acl_shrinker;
134
135 /*
136 * Register the NFS filesystems
137 */
register_nfs_fs(void)138 int __init register_nfs_fs(void)
139 {
140 int ret;
141
142 ret = register_filesystem(&nfs_fs_type);
143 if (ret < 0)
144 goto error_0;
145
146 ret = register_nfs4_fs();
147 if (ret < 0)
148 goto error_1;
149
150 ret = nfs_register_sysctl();
151 if (ret < 0)
152 goto error_2;
153
154 acl_shrinker = shrinker_alloc(0, "nfs-acl");
155 if (!acl_shrinker) {
156 ret = -ENOMEM;
157 goto error_3;
158 }
159
160 acl_shrinker->count_objects = nfs_access_cache_count;
161 acl_shrinker->scan_objects = nfs_access_cache_scan;
162
163 shrinker_register(acl_shrinker);
164
165 #ifdef CONFIG_NFS_V4_2
166 nfs_ssc_register_ops();
167 #endif
168 return 0;
169 error_3:
170 nfs_unregister_sysctl();
171 error_2:
172 unregister_nfs4_fs();
173 error_1:
174 unregister_filesystem(&nfs_fs_type);
175 error_0:
176 return ret;
177 }
178
179 /*
180 * Unregister the NFS filesystems
181 */
unregister_nfs_fs(void)182 void __exit unregister_nfs_fs(void)
183 {
184 shrinker_free(acl_shrinker);
185 nfs_unregister_sysctl();
186 unregister_nfs4_fs();
187 #ifdef CONFIG_NFS_V4_2
188 nfs_ssc_unregister_ops();
189 #endif
190 unregister_filesystem(&nfs_fs_type);
191 }
192
nfs_sb_active(struct super_block * sb)193 bool nfs_sb_active(struct super_block *sb)
194 {
195 struct nfs_server *server = NFS_SB(sb);
196
197 if (!atomic_inc_not_zero(&sb->s_active))
198 return false;
199 if (atomic_inc_return(&server->active) != 1)
200 atomic_dec(&sb->s_active);
201 return true;
202 }
203 EXPORT_SYMBOL_GPL(nfs_sb_active);
204
nfs_sb_deactive(struct super_block * sb)205 void nfs_sb_deactive(struct super_block *sb)
206 {
207 struct nfs_server *server = NFS_SB(sb);
208
209 if (atomic_dec_and_test(&server->active))
210 deactivate_super(sb);
211 }
212 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
213
__nfs_list_for_each_server(struct list_head * head,int (* fn)(struct nfs_server *,void *),void * data)214 static int __nfs_list_for_each_server(struct list_head *head,
215 int (*fn)(struct nfs_server *, void *),
216 void *data)
217 {
218 struct nfs_server *server, *last = NULL;
219 int ret = 0;
220
221 rcu_read_lock();
222 list_for_each_entry_rcu(server, head, client_link) {
223 if (!(server->super && nfs_sb_active(server->super)))
224 continue;
225 rcu_read_unlock();
226 if (last)
227 nfs_sb_deactive(last->super);
228 last = server;
229 ret = fn(server, data);
230 if (ret)
231 goto out;
232 cond_resched();
233 rcu_read_lock();
234 }
235 rcu_read_unlock();
236 out:
237 if (last)
238 nfs_sb_deactive(last->super);
239 return ret;
240 }
241
nfs_client_for_each_server(struct nfs_client * clp,int (* fn)(struct nfs_server *,void *),void * data)242 int nfs_client_for_each_server(struct nfs_client *clp,
243 int (*fn)(struct nfs_server *, void *),
244 void *data)
245 {
246 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data);
247 }
248 EXPORT_SYMBOL_GPL(nfs_client_for_each_server);
249
250 /*
251 * Deliver file system statistics to userspace
252 */
nfs_statfs(struct dentry * dentry,struct kstatfs * buf)253 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
254 {
255 struct nfs_server *server = NFS_SB(dentry->d_sb);
256 unsigned char blockbits;
257 unsigned long blockres;
258 struct nfs_fh *fh = NFS_FH(d_inode(dentry));
259 struct nfs_fsstat res;
260 int error = -ENOMEM;
261
262 res.fattr = nfs_alloc_fattr();
263 if (res.fattr == NULL)
264 goto out_err;
265
266 error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
267 if (unlikely(error == -ESTALE)) {
268 struct dentry *pd_dentry;
269
270 pd_dentry = dget_parent(dentry);
271 nfs_zap_caches(d_inode(pd_dentry));
272 dput(pd_dentry);
273 }
274 nfs_free_fattr(res.fattr);
275 if (error < 0)
276 goto out_err;
277
278 buf->f_type = NFS_SUPER_MAGIC;
279
280 /*
281 * Current versions of glibc do not correctly handle the
282 * case where f_frsize != f_bsize. Eventually we want to
283 * report the value of wtmult in this field.
284 */
285 buf->f_frsize = dentry->d_sb->s_blocksize;
286
287 /*
288 * On most *nix systems, f_blocks, f_bfree, and f_bavail
289 * are reported in units of f_frsize. Linux hasn't had
290 * an f_frsize field in its statfs struct until recently,
291 * thus historically Linux's sys_statfs reports these
292 * fields in units of f_bsize.
293 */
294 buf->f_bsize = dentry->d_sb->s_blocksize;
295 blockbits = dentry->d_sb->s_blocksize_bits;
296 blockres = (1 << blockbits) - 1;
297 buf->f_blocks = (res.tbytes + blockres) >> blockbits;
298 buf->f_bfree = (res.fbytes + blockres) >> blockbits;
299 buf->f_bavail = (res.abytes + blockres) >> blockbits;
300
301 buf->f_files = res.tfiles;
302 buf->f_ffree = res.afiles;
303
304 buf->f_namelen = server->namelen;
305
306 return 0;
307
308 out_err:
309 dprintk("%s: statfs error = %d\n", __func__, -error);
310 return error;
311 }
312 EXPORT_SYMBOL_GPL(nfs_statfs);
313
314 /*
315 * Map the security flavour number to a name
316 */
nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)317 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
318 {
319 static const struct {
320 rpc_authflavor_t flavour;
321 const char *str;
322 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
323 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
324 { RPC_AUTH_NULL, "null" },
325 { RPC_AUTH_UNIX, "sys" },
326 { RPC_AUTH_GSS_KRB5, "krb5" },
327 { RPC_AUTH_GSS_KRB5I, "krb5i" },
328 { RPC_AUTH_GSS_KRB5P, "krb5p" },
329 { RPC_AUTH_GSS_LKEY, "lkey" },
330 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
331 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
332 { RPC_AUTH_GSS_SPKM, "spkm" },
333 { RPC_AUTH_GSS_SPKMI, "spkmi" },
334 { RPC_AUTH_GSS_SPKMP, "spkmp" },
335 { UINT_MAX, "unknown" }
336 };
337 int i;
338
339 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
340 if (sec_flavours[i].flavour == flavour)
341 break;
342 }
343 return sec_flavours[i].str;
344 }
345
nfs_show_mountd_netid(struct seq_file * m,struct nfs_server * nfss,int showdefaults)346 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
347 int showdefaults)
348 {
349 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
350 char *proto = NULL;
351
352 switch (sap->sa_family) {
353 case AF_INET:
354 switch (nfss->mountd_protocol) {
355 case IPPROTO_UDP:
356 proto = RPCBIND_NETID_UDP;
357 break;
358 case IPPROTO_TCP:
359 proto = RPCBIND_NETID_TCP;
360 break;
361 }
362 break;
363 case AF_INET6:
364 switch (nfss->mountd_protocol) {
365 case IPPROTO_UDP:
366 proto = RPCBIND_NETID_UDP6;
367 break;
368 case IPPROTO_TCP:
369 proto = RPCBIND_NETID_TCP6;
370 break;
371 }
372 break;
373 }
374 if (proto || showdefaults)
375 seq_printf(m, ",mountproto=%s", proto ?: "auto");
376 }
377
nfs_show_mountd_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)378 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
379 int showdefaults)
380 {
381 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
382
383 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
384 return;
385
386 switch (sap->sa_family) {
387 case AF_INET: {
388 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
389 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
390 break;
391 }
392 case AF_INET6: {
393 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
394 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
395 break;
396 }
397 default:
398 if (showdefaults)
399 seq_puts(m, ",mountaddr=unspecified");
400 }
401
402 if (nfss->mountd_version || showdefaults)
403 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
404 if ((nfss->mountd_port &&
405 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
406 showdefaults)
407 seq_printf(m, ",mountport=%u", nfss->mountd_port);
408
409 nfs_show_mountd_netid(m, nfss, showdefaults);
410 }
411
412 #if IS_ENABLED(CONFIG_NFS_V4)
nfs_show_nfsv4_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)413 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
414 int showdefaults)
415 {
416 struct nfs_client *clp = nfss->nfs_client;
417
418 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
419 }
420 #else
nfs_show_nfsv4_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)421 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
422 int showdefaults)
423 {
424 }
425 #endif
426
nfs_show_nfs_version(struct seq_file * m,unsigned int version,unsigned int minorversion)427 static void nfs_show_nfs_version(struct seq_file *m,
428 unsigned int version,
429 unsigned int minorversion)
430 {
431 seq_printf(m, ",vers=%u", version);
432 if (version == 4)
433 seq_printf(m, ".%u", minorversion);
434 }
435
436 /*
437 * Describe the mount options in force on this server representation
438 */
nfs_show_mount_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)439 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
440 int showdefaults)
441 {
442 static const struct proc_nfs_info {
443 int flag;
444 const char *str;
445 const char *nostr;
446 } nfs_info[] = {
447 { NFS_MOUNT_SOFT, ",soft", "" },
448 { NFS_MOUNT_SOFTERR, ",softerr", "" },
449 { NFS_MOUNT_SOFTREVAL, ",softreval", "" },
450 { NFS_MOUNT_POSIX, ",posix", "" },
451 { NFS_MOUNT_NOCTO, ",nocto", "" },
452 { NFS_MOUNT_NOAC, ",noac", "" },
453 { NFS_MOUNT_NONLM, ",nolock", "" },
454 { NFS_MOUNT_NOACL, ",noacl", "" },
455 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
456 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
457 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
458 { 0, NULL, NULL }
459 };
460 const struct proc_nfs_info *nfs_infop;
461 struct nfs_client *clp = nfss->nfs_client;
462 u32 version = clp->rpc_ops->version;
463 int local_flock, local_fcntl;
464
465 nfs_show_nfs_version(m, version, clp->cl_minorversion);
466 seq_printf(m, ",rsize=%u", nfss->rsize);
467 seq_printf(m, ",wsize=%u", nfss->wsize);
468 if (nfss->bsize != 0)
469 seq_printf(m, ",bsize=%u", nfss->bsize);
470 seq_printf(m, ",namlen=%u", nfss->namelen);
471 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
472 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
473 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
474 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
475 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
476 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
477 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
478 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
479 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
480 seq_puts(m, ",hard");
481 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
482 if (nfss->flags & nfs_infop->flag)
483 seq_puts(m, nfs_infop->str);
484 else
485 seq_puts(m, nfs_infop->nostr);
486 }
487 rcu_read_lock();
488 seq_printf(m, ",proto=%s",
489 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
490 rcu_read_unlock();
491 if (clp->cl_nconnect > 0)
492 seq_printf(m, ",nconnect=%u", clp->cl_nconnect);
493 if (version == 4) {
494 if (clp->cl_max_connect > 1)
495 seq_printf(m, ",max_connect=%u", clp->cl_max_connect);
496 if (nfss->port != NFS_PORT)
497 seq_printf(m, ",port=%u", nfss->port);
498 } else
499 if (nfss->port)
500 seq_printf(m, ",port=%u", nfss->port);
501
502 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
503 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
504 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
505 switch (clp->cl_xprtsec.policy) {
506 case RPC_XPRTSEC_TLS_ANON:
507 seq_puts(m, ",xprtsec=tls");
508 break;
509 case RPC_XPRTSEC_TLS_X509:
510 seq_puts(m, ",xprtsec=mtls");
511 break;
512 default:
513 break;
514 }
515
516 if (version != 4)
517 nfs_show_mountd_options(m, nfss, showdefaults);
518 else
519 nfs_show_nfsv4_options(m, nfss, showdefaults);
520
521 if (nfss->options & NFS_OPTION_FSCACHE) {
522 #ifdef CONFIG_NFS_FSCACHE
523 if (nfss->fscache_uniq)
524 seq_printf(m, ",fsc=%s", nfss->fscache_uniq);
525 else
526 seq_puts(m, ",fsc");
527 #else
528 seq_puts(m, ",fsc");
529 #endif
530 }
531
532 if (nfss->options & NFS_OPTION_MIGRATION)
533 seq_puts(m, ",migration");
534
535 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
536 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
537 seq_puts(m, ",lookupcache=none");
538 else
539 seq_puts(m, ",lookupcache=pos");
540 }
541
542 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
543 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
544
545 if (!local_flock && !local_fcntl)
546 seq_puts(m, ",local_lock=none");
547 else if (local_flock && local_fcntl)
548 seq_puts(m, ",local_lock=all");
549 else if (local_flock)
550 seq_puts(m, ",local_lock=flock");
551 else
552 seq_puts(m, ",local_lock=posix");
553
554 if (nfss->flags & NFS_MOUNT_NO_ALIGNWRITE)
555 seq_puts(m, ",noalignwrite");
556
557 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) {
558 if (nfss->flags & NFS_MOUNT_WRITE_WAIT)
559 seq_puts(m, ",write=wait");
560 else
561 seq_puts(m, ",write=eager");
562 }
563 }
564
565 /*
566 * Describe the mount options on this VFS mountpoint
567 */
nfs_show_options(struct seq_file * m,struct dentry * root)568 int nfs_show_options(struct seq_file *m, struct dentry *root)
569 {
570 struct nfs_server *nfss = NFS_SB(root->d_sb);
571
572 nfs_show_mount_options(m, nfss, 0);
573
574 rcu_read_lock();
575 seq_printf(m, ",addr=%s",
576 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
577 RPC_DISPLAY_ADDR));
578 rcu_read_unlock();
579
580 return 0;
581 }
582 EXPORT_SYMBOL_GPL(nfs_show_options);
583
584 #if IS_ENABLED(CONFIG_NFS_V4)
show_lease(struct seq_file * m,struct nfs_server * server)585 static void show_lease(struct seq_file *m, struct nfs_server *server)
586 {
587 struct nfs_client *clp = server->nfs_client;
588 unsigned long expire;
589
590 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ);
591 expire = clp->cl_last_renewal + clp->cl_lease_time;
592 seq_printf(m, ",lease_expired=%ld",
593 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ);
594 }
595 #ifdef CONFIG_NFS_V4_1
show_sessions(struct seq_file * m,struct nfs_server * server)596 static void show_sessions(struct seq_file *m, struct nfs_server *server)
597 {
598 if (nfs4_has_session(server->nfs_client))
599 seq_puts(m, ",sessions");
600 }
601 #else
show_sessions(struct seq_file * m,struct nfs_server * server)602 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
603 #endif
604 #endif
605
606 #ifdef CONFIG_NFS_V4_1
show_pnfs(struct seq_file * m,struct nfs_server * server)607 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
608 {
609 seq_printf(m, ",pnfs=");
610 if (server->pnfs_curr_ld)
611 seq_printf(m, "%s", server->pnfs_curr_ld->name);
612 else
613 seq_printf(m, "not configured");
614 }
615
show_implementation_id(struct seq_file * m,struct nfs_server * nfss)616 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
617 {
618 if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
619 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
620 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
621 "date='%llu,%u'",
622 impl_id->name, impl_id->domain,
623 impl_id->date.seconds, impl_id->date.nseconds);
624 }
625 }
626 #else
627 #if IS_ENABLED(CONFIG_NFS_V4)
show_pnfs(struct seq_file * m,struct nfs_server * server)628 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
629 {
630 }
631 #endif
show_implementation_id(struct seq_file * m,struct nfs_server * nfss)632 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
633 {
634 }
635 #endif
636
nfs_show_devname(struct seq_file * m,struct dentry * root)637 int nfs_show_devname(struct seq_file *m, struct dentry *root)
638 {
639 char *page = (char *) __get_free_page(GFP_KERNEL);
640 char *devname, *dummy;
641 int err = 0;
642 if (!page)
643 return -ENOMEM;
644 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
645 if (IS_ERR(devname))
646 err = PTR_ERR(devname);
647 else
648 seq_escape(m, devname, " \t\n\\");
649 free_page((unsigned long)page);
650 return err;
651 }
652 EXPORT_SYMBOL_GPL(nfs_show_devname);
653
nfs_show_path(struct seq_file * m,struct dentry * dentry)654 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
655 {
656 seq_puts(m, "/");
657 return 0;
658 }
659 EXPORT_SYMBOL_GPL(nfs_show_path);
660
661 /*
662 * Present statistical information for this VFS mountpoint
663 */
nfs_show_stats(struct seq_file * m,struct dentry * root)664 int nfs_show_stats(struct seq_file *m, struct dentry *root)
665 {
666 int i, cpu;
667 struct nfs_server *nfss = NFS_SB(root->d_sb);
668 struct rpc_auth *auth = nfss->client->cl_auth;
669 struct nfs_iostats totals = { };
670
671 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
672
673 /*
674 * Display all mount option settings
675 */
676 seq_puts(m, "\n\topts:\t");
677 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
678 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
679 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
680 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
681 nfs_show_mount_options(m, nfss, 1);
682
683 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
684
685 show_implementation_id(m, nfss);
686
687 seq_puts(m, "\n\tcaps:\t");
688 seq_printf(m, "caps=0x%x", nfss->caps);
689 seq_printf(m, ",wtmult=%u", nfss->wtmult);
690 seq_printf(m, ",dtsize=%u", nfss->dtsize);
691 seq_printf(m, ",bsize=%u", nfss->bsize);
692 seq_printf(m, ",namlen=%u", nfss->namelen);
693
694 #if IS_ENABLED(CONFIG_NFS_V4)
695 if (nfss->nfs_client->rpc_ops->version == 4) {
696 seq_puts(m, "\n\tnfsv4:\t");
697 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
698 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
699 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
700 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
701 show_sessions(m, nfss);
702 show_pnfs(m, nfss);
703 show_lease(m, nfss);
704 }
705 #endif
706
707 /*
708 * Display security flavor in effect for this mount
709 */
710 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
711 if (auth->au_flavor)
712 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
713
714 /*
715 * Display superblock I/O counters
716 */
717 for_each_possible_cpu(cpu) {
718 struct nfs_iostats *stats;
719
720 preempt_disable();
721 stats = per_cpu_ptr(nfss->io_stats, cpu);
722
723 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
724 totals.events[i] += stats->events[i];
725 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
726 totals.bytes[i] += stats->bytes[i];
727
728 preempt_enable();
729 }
730
731 seq_puts(m, "\n\tevents:\t");
732 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
733 seq_printf(m, "%lu ", totals.events[i]);
734 seq_puts(m, "\n\tbytes:\t");
735 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
736 seq_printf(m, "%Lu ", totals.bytes[i]);
737 seq_putc(m, '\n');
738
739 rpc_clnt_show_stats(m, nfss->client);
740
741 return 0;
742 }
743 EXPORT_SYMBOL_GPL(nfs_show_stats);
744
745 /*
746 * Begin unmount by attempting to remove all automounted mountpoints we added
747 * in response to xdev traversals and referrals
748 */
nfs_umount_begin(struct super_block * sb)749 void nfs_umount_begin(struct super_block *sb)
750 {
751 struct nfs_server *server;
752 struct rpc_clnt *rpc;
753
754 server = NFS_SB(sb);
755 /* -EIO all pending I/O */
756 rpc = server->client_acl;
757 if (!IS_ERR(rpc))
758 rpc_killall_tasks(rpc);
759 rpc = server->client;
760 if (!IS_ERR(rpc))
761 rpc_killall_tasks(rpc);
762 }
763 EXPORT_SYMBOL_GPL(nfs_umount_begin);
764
765 /*
766 * Return true if 'match' is in auth_info or auth_info is empty.
767 * Return false otherwise.
768 */
nfs_auth_info_match(const struct nfs_auth_info * auth_info,rpc_authflavor_t match)769 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
770 rpc_authflavor_t match)
771 {
772 int i;
773
774 if (!auth_info->flavor_len)
775 return true;
776
777 for (i = 0; i < auth_info->flavor_len; i++) {
778 if (auth_info->flavors[i] == match)
779 return true;
780 }
781 return false;
782 }
783 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
784
785 /*
786 * Ensure that a specified authtype in ctx->auth_info is supported by
787 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and
788 * -EACCES if not.
789 */
nfs_verify_authflavors(struct nfs_fs_context * ctx,rpc_authflavor_t * server_authlist,unsigned int count)790 static int nfs_verify_authflavors(struct nfs_fs_context *ctx,
791 rpc_authflavor_t *server_authlist,
792 unsigned int count)
793 {
794 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
795 bool found_auth_null = false;
796 unsigned int i;
797
798 /*
799 * If the sec= mount option is used, the specified flavor or AUTH_NULL
800 * must be in the list returned by the server.
801 *
802 * AUTH_NULL has a special meaning when it's in the server list - it
803 * means that the server will ignore the rpc creds, so any flavor
804 * can be used but still use the sec= that was specified.
805 *
806 * Note also that the MNT procedure in MNTv1 does not return a list
807 * of supported security flavors. In this case, nfs_mount() fabricates
808 * a security flavor list containing just AUTH_NULL.
809 */
810 for (i = 0; i < count; i++) {
811 flavor = server_authlist[i];
812
813 if (nfs_auth_info_match(&ctx->auth_info, flavor))
814 goto out;
815
816 if (flavor == RPC_AUTH_NULL)
817 found_auth_null = true;
818 }
819
820 if (found_auth_null) {
821 flavor = ctx->auth_info.flavors[0];
822 goto out;
823 }
824
825 dfprintk(MOUNT,
826 "NFS: specified auth flavors not supported by server\n");
827 return -EACCES;
828
829 out:
830 ctx->selected_flavor = flavor;
831 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor);
832 return 0;
833 }
834
835 /*
836 * Use the remote server's MOUNT service to request the NFS file handle
837 * corresponding to the provided path.
838 */
nfs_request_mount(struct fs_context * fc,struct nfs_fh * root_fh,rpc_authflavor_t * server_authlist,unsigned int * server_authlist_len)839 static int nfs_request_mount(struct fs_context *fc,
840 struct nfs_fh *root_fh,
841 rpc_authflavor_t *server_authlist,
842 unsigned int *server_authlist_len)
843 {
844 struct nfs_fs_context *ctx = nfs_fc2context(fc);
845 struct nfs_mount_request request = {
846 .sap = &ctx->mount_server._address,
847 .dirpath = ctx->nfs_server.export_path,
848 .protocol = ctx->mount_server.protocol,
849 .fh = root_fh,
850 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT,
851 .auth_flav_len = server_authlist_len,
852 .auth_flavs = server_authlist,
853 .net = fc->net_ns,
854 };
855 int status;
856
857 if (ctx->mount_server.version == 0) {
858 switch (ctx->version) {
859 default:
860 ctx->mount_server.version = NFS_MNT3_VERSION;
861 break;
862 case 2:
863 ctx->mount_server.version = NFS_MNT_VERSION;
864 }
865 }
866 request.version = ctx->mount_server.version;
867
868 if (ctx->mount_server.hostname)
869 request.hostname = ctx->mount_server.hostname;
870 else
871 request.hostname = ctx->nfs_server.hostname;
872
873 /*
874 * Construct the mount server's address.
875 */
876 if (ctx->mount_server.address.sa_family == AF_UNSPEC) {
877 memcpy(request.sap, &ctx->nfs_server._address,
878 ctx->nfs_server.addrlen);
879 ctx->mount_server.addrlen = ctx->nfs_server.addrlen;
880 }
881 request.salen = ctx->mount_server.addrlen;
882 nfs_set_port(request.sap, &ctx->mount_server.port, 0);
883
884 /*
885 * Now ask the mount server to map our export path
886 * to a file handle.
887 */
888 status = nfs_mount(&request, ctx->timeo, ctx->retrans);
889 if (status != 0) {
890 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
891 request.hostname, status);
892 return status;
893 }
894
895 return 0;
896 }
897
nfs_try_mount_request(struct fs_context * fc)898 static struct nfs_server *nfs_try_mount_request(struct fs_context *fc)
899 {
900 struct nfs_fs_context *ctx = nfs_fc2context(fc);
901 int status;
902 unsigned int i;
903 bool tried_auth_unix = false;
904 bool auth_null_in_list = false;
905 struct nfs_server *server = ERR_PTR(-EACCES);
906 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
907 unsigned int authlist_len = ARRAY_SIZE(authlist);
908
909 /* make sure 'nolock'/'lock' override the 'local_lock' mount option */
910 if (ctx->lock_status) {
911 if (ctx->lock_status == NFS_LOCK_NOLOCK) {
912 ctx->flags |= NFS_MOUNT_NONLM;
913 ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
914 } else {
915 ctx->flags &= ~NFS_MOUNT_NONLM;
916 ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
917 }
918 }
919 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len);
920 if (status)
921 return ERR_PTR(status);
922
923 /*
924 * Was a sec= authflavor specified in the options? First, verify
925 * whether the server supports it, and then just try to use it if so.
926 */
927 if (ctx->auth_info.flavor_len > 0) {
928 status = nfs_verify_authflavors(ctx, authlist, authlist_len);
929 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
930 ctx->selected_flavor);
931 if (status)
932 return ERR_PTR(status);
933 return ctx->nfs_mod->rpc_ops->create_server(fc);
934 }
935
936 /*
937 * No sec= option was provided. RFC 2623, section 2.7 suggests we
938 * SHOULD prefer the flavor listed first. However, some servers list
939 * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
940 */
941 for (i = 0; i < authlist_len; ++i) {
942 rpc_authflavor_t flavor;
943 struct rpcsec_gss_info info;
944
945 flavor = authlist[i];
946 switch (flavor) {
947 case RPC_AUTH_UNIX:
948 tried_auth_unix = true;
949 break;
950 case RPC_AUTH_NULL:
951 auth_null_in_list = true;
952 continue;
953 default:
954 if (rpcauth_get_gssinfo(flavor, &info) != 0)
955 continue;
956 break;
957 }
958 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
959 ctx->selected_flavor = flavor;
960 server = ctx->nfs_mod->rpc_ops->create_server(fc);
961 if (!IS_ERR(server))
962 return server;
963 }
964
965 /*
966 * Nothing we tried so far worked. At this point, give up if we've
967 * already tried AUTH_UNIX or if the server's list doesn't contain
968 * AUTH_NULL
969 */
970 if (tried_auth_unix || !auth_null_in_list)
971 return server;
972
973 /* Last chance! Try AUTH_UNIX */
974 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
975 ctx->selected_flavor = RPC_AUTH_UNIX;
976 return ctx->nfs_mod->rpc_ops->create_server(fc);
977 }
978
nfs_try_get_tree(struct fs_context * fc)979 int nfs_try_get_tree(struct fs_context *fc)
980 {
981 struct nfs_fs_context *ctx = nfs_fc2context(fc);
982
983 if (ctx->need_mount)
984 ctx->server = nfs_try_mount_request(fc);
985 else
986 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc);
987
988 return nfs_get_tree_common(fc);
989 }
990 EXPORT_SYMBOL_GPL(nfs_try_get_tree);
991
992
993 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
994 | NFS_MOUNT_SECURE \
995 | NFS_MOUNT_TCP \
996 | NFS_MOUNT_VER3 \
997 | NFS_MOUNT_KERBEROS \
998 | NFS_MOUNT_NONLM \
999 | NFS_MOUNT_BROKEN_SUID \
1000 | NFS_MOUNT_STRICTLOCK \
1001 | NFS_MOUNT_LEGACY_INTERFACE)
1002
1003 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
1004 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
1005
1006 static int
nfs_compare_remount_data(struct nfs_server * nfss,struct nfs_fs_context * ctx)1007 nfs_compare_remount_data(struct nfs_server *nfss,
1008 struct nfs_fs_context *ctx)
1009 {
1010 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
1011 ctx->rsize != nfss->rsize ||
1012 ctx->wsize != nfss->wsize ||
1013 ctx->version != nfss->nfs_client->rpc_ops->version ||
1014 ctx->minorversion != nfss->nfs_client->cl_minorversion ||
1015 ctx->retrans != nfss->client->cl_timeout->to_retries ||
1016 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) ||
1017 ctx->acregmin != nfss->acregmin / HZ ||
1018 ctx->acregmax != nfss->acregmax / HZ ||
1019 ctx->acdirmin != nfss->acdirmin / HZ ||
1020 ctx->acdirmax != nfss->acdirmax / HZ ||
1021 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1022 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) ||
1023 ctx->nfs_server.port != nfss->port ||
1024 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1025 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address,
1026 (struct sockaddr *)&nfss->nfs_client->cl_addr))
1027 return -EINVAL;
1028
1029 return 0;
1030 }
1031
nfs_reconfigure(struct fs_context * fc)1032 int nfs_reconfigure(struct fs_context *fc)
1033 {
1034 struct nfs_fs_context *ctx = nfs_fc2context(fc);
1035 struct super_block *sb = fc->root->d_sb;
1036 struct nfs_server *nfss = sb->s_fs_info;
1037 int ret;
1038
1039 sync_filesystem(sb);
1040
1041 /*
1042 * Userspace mount programs that send binary options generally send
1043 * them populated with default values. We have no way to know which
1044 * ones were explicitly specified. Fall back to legacy behavior and
1045 * just return success.
1046 */
1047 if (ctx->skip_reconfig_option_check)
1048 return 0;
1049
1050 /*
1051 * noac is a special case. It implies -o sync, but that's not
1052 * necessarily reflected in the mtab options. reconfigure_super
1053 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
1054 * remount options, so we have to explicitly reset it.
1055 */
1056 if (ctx->flags & NFS_MOUNT_NOAC) {
1057 fc->sb_flags |= SB_SYNCHRONOUS;
1058 fc->sb_flags_mask |= SB_SYNCHRONOUS;
1059 }
1060
1061 /* compare new mount options with old ones */
1062 ret = nfs_compare_remount_data(nfss, ctx);
1063 if (ret)
1064 return ret;
1065
1066 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root)));
1067 }
1068 EXPORT_SYMBOL_GPL(nfs_reconfigure);
1069
1070 /*
1071 * Finish setting up an NFS superblock
1072 */
nfs_fill_super(struct super_block * sb,struct nfs_fs_context * ctx)1073 static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx)
1074 {
1075 struct nfs_server *server = NFS_SB(sb);
1076
1077 sb->s_blocksize_bits = 0;
1078 sb->s_blocksize = 0;
1079 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
1080 sb->s_op = server->nfs_client->cl_nfs_mod->sops;
1081 if (ctx->bsize)
1082 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits);
1083
1084 switch (server->nfs_client->rpc_ops->version) {
1085 case 2:
1086 sb->s_time_gran = 1000;
1087 sb->s_time_min = 0;
1088 sb->s_time_max = U32_MAX;
1089 break;
1090 case 3:
1091 /*
1092 * The VFS shouldn't apply the umask to mode bits.
1093 * We will do so ourselves when necessary.
1094 */
1095 sb->s_flags |= SB_POSIXACL;
1096 sb->s_time_gran = 1;
1097 sb->s_time_min = 0;
1098 sb->s_time_max = U32_MAX;
1099 sb->s_export_op = &nfs_export_ops;
1100 break;
1101 case 4:
1102 sb->s_iflags |= SB_I_NOUMASK;
1103 sb->s_time_gran = 1;
1104 sb->s_time_min = S64_MIN;
1105 sb->s_time_max = S64_MAX;
1106 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1)
1107 sb->s_export_op = &nfs_export_ops;
1108 break;
1109 }
1110
1111 sb->s_magic = NFS_SUPER_MAGIC;
1112
1113 /* We probably want something more informative here */
1114 snprintf(sb->s_id, sizeof(sb->s_id),
1115 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1116
1117 if (sb->s_blocksize == 0)
1118 sb->s_blocksize = nfs_block_bits(server->wsize,
1119 &sb->s_blocksize_bits);
1120
1121 nfs_super_set_maxbytes(sb, server->maxfilesize);
1122 nfs_sysfs_move_server_to_sb(sb);
1123 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts;
1124 }
1125
nfs_compare_mount_options(const struct super_block * s,const struct nfs_server * b,const struct fs_context * fc)1126 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b,
1127 const struct fs_context *fc)
1128 {
1129 const struct nfs_server *a = s->s_fs_info;
1130 const struct rpc_clnt *clnt_a = a->client;
1131 const struct rpc_clnt *clnt_b = b->client;
1132
1133 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK))
1134 goto Ebusy;
1135 if (a->nfs_client != b->nfs_client)
1136 goto Ebusy;
1137 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
1138 goto Ebusy;
1139 if (a->wsize != b->wsize)
1140 goto Ebusy;
1141 if (a->rsize != b->rsize)
1142 goto Ebusy;
1143 if (a->acregmin != b->acregmin)
1144 goto Ebusy;
1145 if (a->acregmax != b->acregmax)
1146 goto Ebusy;
1147 if (a->acdirmin != b->acdirmin)
1148 goto Ebusy;
1149 if (a->acdirmax != b->acdirmax)
1150 goto Ebusy;
1151 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1152 goto Ebusy;
1153 return 1;
1154 Ebusy:
1155 return 0;
1156 }
1157
nfs_set_super(struct super_block * s,struct fs_context * fc)1158 static int nfs_set_super(struct super_block *s, struct fs_context *fc)
1159 {
1160 struct nfs_server *server = fc->s_fs_info;
1161 int ret;
1162
1163 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
1164 ret = set_anon_super(s, server);
1165 if (ret == 0)
1166 server->s_dev = s->s_dev;
1167 return ret;
1168 }
1169
nfs_compare_super_address(struct nfs_server * server1,struct nfs_server * server2)1170 static int nfs_compare_super_address(struct nfs_server *server1,
1171 struct nfs_server *server2)
1172 {
1173 struct sockaddr *sap1, *sap2;
1174 struct rpc_xprt *xprt1 = server1->client->cl_xprt;
1175 struct rpc_xprt *xprt2 = server2->client->cl_xprt;
1176
1177 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
1178 return 0;
1179
1180 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1181 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1182
1183 if (sap1->sa_family != sap2->sa_family)
1184 return 0;
1185
1186 switch (sap1->sa_family) {
1187 case AF_INET: {
1188 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1189 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1190 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1191 return 0;
1192 if (sin1->sin_port != sin2->sin_port)
1193 return 0;
1194 break;
1195 }
1196 case AF_INET6: {
1197 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1198 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1199 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1200 return 0;
1201 if (sin1->sin6_port != sin2->sin6_port)
1202 return 0;
1203 break;
1204 }
1205 default:
1206 return 0;
1207 }
1208
1209 return 1;
1210 }
1211
nfs_compare_userns(const struct nfs_server * old,const struct nfs_server * new)1212 static int nfs_compare_userns(const struct nfs_server *old,
1213 const struct nfs_server *new)
1214 {
1215 const struct user_namespace *oldns = &init_user_ns;
1216 const struct user_namespace *newns = &init_user_ns;
1217
1218 if (old->client && old->client->cl_cred)
1219 oldns = old->client->cl_cred->user_ns;
1220 if (new->client && new->client->cl_cred)
1221 newns = new->client->cl_cred->user_ns;
1222 if (oldns != newns)
1223 return 0;
1224 return 1;
1225 }
1226
nfs_compare_super(struct super_block * sb,struct fs_context * fc)1227 static int nfs_compare_super(struct super_block *sb, struct fs_context *fc)
1228 {
1229 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb);
1230
1231 if (!nfs_compare_super_address(old, server))
1232 return 0;
1233 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1234 if (old->flags & NFS_MOUNT_UNSHARED)
1235 return 0;
1236 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1237 return 0;
1238 if (!nfs_compare_userns(old, server))
1239 return 0;
1240 if ((old->has_sec_mnt_opts || fc->security) &&
1241 security_sb_mnt_opts_compat(sb, fc->security))
1242 return 0;
1243 return nfs_compare_mount_options(sb, server, fc);
1244 }
1245
1246 #ifdef CONFIG_NFS_FSCACHE
nfs_get_cache_cookie(struct super_block * sb,struct nfs_fs_context * ctx)1247 static int nfs_get_cache_cookie(struct super_block *sb,
1248 struct nfs_fs_context *ctx)
1249 {
1250 struct nfs_server *nfss = NFS_SB(sb);
1251 char *uniq = NULL;
1252 int ulen = 0;
1253
1254 nfss->fscache = NULL;
1255
1256 if (!ctx)
1257 return 0;
1258
1259 if (ctx->clone_data.sb) {
1260 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb);
1261 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
1262 return 0;
1263 if (mnt_s->fscache_uniq) {
1264 uniq = mnt_s->fscache_uniq;
1265 ulen = strlen(uniq);
1266 }
1267 } else {
1268 if (!(ctx->options & NFS_OPTION_FSCACHE))
1269 return 0;
1270 if (ctx->fscache_uniq) {
1271 uniq = ctx->fscache_uniq;
1272 ulen = strlen(ctx->fscache_uniq);
1273 }
1274 }
1275
1276 return nfs_fscache_get_super_cookie(sb, uniq, ulen);
1277 }
1278 #else
nfs_get_cache_cookie(struct super_block * sb,struct nfs_fs_context * ctx)1279 static int nfs_get_cache_cookie(struct super_block *sb,
1280 struct nfs_fs_context *ctx)
1281 {
1282 return 0;
1283 }
1284 #endif
1285
nfs_get_tree_common(struct fs_context * fc)1286 int nfs_get_tree_common(struct fs_context *fc)
1287 {
1288 struct nfs_fs_context *ctx = nfs_fc2context(fc);
1289 struct super_block *s;
1290 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super;
1291 struct nfs_server *server = ctx->server;
1292 int error;
1293
1294 ctx->server = NULL;
1295 if (IS_ERR(server))
1296 return PTR_ERR(server);
1297
1298 if (server->flags & NFS_MOUNT_UNSHARED)
1299 compare_super = NULL;
1300
1301 /* -o noac implies -o sync */
1302 if (server->flags & NFS_MOUNT_NOAC)
1303 fc->sb_flags |= SB_SYNCHRONOUS;
1304
1305 if (ctx->clone_data.sb)
1306 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS)
1307 fc->sb_flags |= SB_SYNCHRONOUS;
1308
1309 /* Get a superblock - note that we may end up sharing one that already exists */
1310 fc->s_fs_info = server;
1311 s = sget_fc(fc, compare_super, nfs_set_super);
1312 fc->s_fs_info = NULL;
1313 if (IS_ERR(s)) {
1314 error = PTR_ERR(s);
1315 nfs_errorf(fc, "NFS: Couldn't get superblock");
1316 goto out_err_nosb;
1317 }
1318
1319 if (s->s_fs_info != server) {
1320 nfs_free_server(server);
1321 server = NULL;
1322 } else {
1323 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
1324 MINOR(server->s_dev));
1325 if (error)
1326 goto error_splat_super;
1327 s->s_bdi->io_pages = server->rpages;
1328 server->super = s;
1329 }
1330
1331 if (!s->s_root) {
1332 unsigned bsize = ctx->clone_data.inherited_bsize;
1333 /* initial superblock/root creation */
1334 nfs_fill_super(s, ctx);
1335 if (bsize) {
1336 s->s_blocksize_bits = bsize;
1337 s->s_blocksize = 1U << bsize;
1338 }
1339 error = nfs_get_cache_cookie(s, ctx);
1340 if (error < 0)
1341 goto error_splat_super;
1342 }
1343
1344 error = nfs_get_root(s, fc);
1345 if (error < 0) {
1346 nfs_errorf(fc, "NFS: Couldn't get root dentry");
1347 goto error_splat_super;
1348 }
1349
1350 s->s_flags |= SB_ACTIVE;
1351 error = 0;
1352
1353 out:
1354 return error;
1355
1356 out_err_nosb:
1357 nfs_free_server(server);
1358 goto out;
1359 error_splat_super:
1360 deactivate_locked_super(s);
1361 goto out;
1362 }
1363
1364 /*
1365 * Destroy an NFS superblock
1366 */
nfs_kill_super(struct super_block * s)1367 void nfs_kill_super(struct super_block *s)
1368 {
1369 struct nfs_server *server = NFS_SB(s);
1370
1371 nfs_sysfs_move_sb_to_server(server);
1372 kill_anon_super(s);
1373
1374 nfs_fscache_release_super_cookie(s);
1375
1376 nfs_free_server(server);
1377 }
1378 EXPORT_SYMBOL_GPL(nfs_kill_super);
1379
1380 #if IS_ENABLED(CONFIG_NFS_V4)
1381
1382 /*
1383 * NFS v4 module parameters need to stay in the
1384 * NFS client for backwards compatibility
1385 */
1386 unsigned int nfs_callback_set_tcpport;
1387 unsigned short nfs_callback_nr_threads;
1388 /* Default cache timeout is 10 minutes */
1389 unsigned int nfs_idmap_cache_timeout = 600;
1390 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
1391 bool nfs4_disable_idmapping = true;
1392 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
1393 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
1394 unsigned short send_implementation_id = 1;
1395 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
1396 bool recover_lost_locks = false;
1397 short nfs_delay_retrans = -1;
1398
1399 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
1400 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
1401 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
1402 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
1403 EXPORT_SYMBOL_GPL(max_session_slots);
1404 EXPORT_SYMBOL_GPL(max_session_cb_slots);
1405 EXPORT_SYMBOL_GPL(send_implementation_id);
1406 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
1407 EXPORT_SYMBOL_GPL(recover_lost_locks);
1408 EXPORT_SYMBOL_GPL(nfs_delay_retrans);
1409
1410 #define NFS_CALLBACK_MAXPORTNR (65535U)
1411
param_set_portnr(const char * val,const struct kernel_param * kp)1412 static int param_set_portnr(const char *val, const struct kernel_param *kp)
1413 {
1414 unsigned long num;
1415 int ret;
1416
1417 if (!val)
1418 return -EINVAL;
1419 ret = kstrtoul(val, 0, &num);
1420 if (ret || num > NFS_CALLBACK_MAXPORTNR)
1421 return -EINVAL;
1422 *((unsigned int *)kp->arg) = num;
1423 return 0;
1424 }
1425 static const struct kernel_param_ops param_ops_portnr = {
1426 .set = param_set_portnr,
1427 .get = param_get_uint,
1428 };
1429 #define param_check_portnr(name, p) __param_check(name, p, unsigned int)
1430
1431 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
1432 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
1433 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
1434 "assigned to the NFSv4 callback channels.");
1435 module_param(nfs_idmap_cache_timeout, int, 0644);
1436 module_param(nfs4_disable_idmapping, bool, 0644);
1437 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
1438 NFS4_CLIENT_ID_UNIQ_LEN, 0600);
1439 MODULE_PARM_DESC(nfs4_disable_idmapping,
1440 "Turn off NFSv4 idmapping when using 'sec=sys'");
1441 module_param(max_session_slots, ushort, 0644);
1442 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
1443 "requests the client will negotiate");
1444 module_param(max_session_cb_slots, ushort, 0644);
1445 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
1446 "callbacks the client will process for a given server");
1447 module_param(send_implementation_id, ushort, 0644);
1448 MODULE_PARM_DESC(send_implementation_id,
1449 "Send implementation ID with NFSv4.1 exchange_id");
1450 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
1451
1452 module_param(recover_lost_locks, bool, 0644);
1453 MODULE_PARM_DESC(recover_lost_locks,
1454 "If the server reports that a lock might be lost, "
1455 "try to recover it risking data corruption.");
1456
1457 module_param_named(delay_retrans, nfs_delay_retrans, short, 0644);
1458 MODULE_PARM_DESC(delay_retrans,
1459 "Unless negative, specifies the number of times the NFSv4 "
1460 "client retries a request before returning an EAGAIN error, "
1461 "after a reply of NFS4ERR_DELAY from the server.");
1462 #endif /* CONFIG_NFS_V4 */
1463