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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/slab.h>
51#include <net/ipv6.h>
52#include <linux/netdevice.h>
53#include <linux/nfs_xdr.h>
54#include <linux/magic.h>
55#include <linux/parser.h>
56#include <linux/nsproxy.h>
57#include <linux/rcupdate.h>
58
59#include <linux/uaccess.h>
60#include <linux/nfs_ssc.h>
61
62#include "nfs4_fs.h"
63#include "callback.h"
64#include "delegation.h"
65#include "iostat.h"
66#include "internal.h"
67#include "fscache.h"
68#include "nfs4session.h"
69#include "pnfs.h"
70#include "nfs.h"
71
72#define NFSDBG_FACILITY NFSDBG_VFS
73
74const struct super_operations nfs_sops = {
75 .alloc_inode = nfs_alloc_inode,
76 .free_inode = nfs_free_inode,
77 .write_inode = nfs_write_inode,
78 .drop_inode = nfs_drop_inode,
79 .statfs = nfs_statfs,
80 .evict_inode = nfs_evict_inode,
81 .umount_begin = nfs_umount_begin,
82 .show_options = nfs_show_options,
83 .show_devname = nfs_show_devname,
84 .show_path = nfs_show_path,
85 .show_stats = nfs_show_stats,
86};
87EXPORT_SYMBOL_GPL(nfs_sops);
88
89#ifdef CONFIG_NFS_V4_2
90static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = {
91 .sco_sb_deactive = nfs_sb_deactive,
92};
93#endif
94
95#if IS_ENABLED(CONFIG_NFS_V4)
96static int __init register_nfs4_fs(void)
97{
98 return register_filesystem(&nfs4_fs_type);
99}
100
101static void unregister_nfs4_fs(void)
102{
103 unregister_filesystem(&nfs4_fs_type);
104}
105#else
106static int __init register_nfs4_fs(void)
107{
108 return 0;
109}
110
111static void unregister_nfs4_fs(void)
112{
113}
114#endif
115
116#ifdef CONFIG_NFS_V4_2
117static void nfs_ssc_register_ops(void)
118{
119 nfs_ssc_register(&nfs_ssc_clnt_ops_tbl);
120}
121
122static void nfs_ssc_unregister_ops(void)
123{
124 nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl);
125}
126#endif /* CONFIG_NFS_V4_2 */
127
128static struct shrinker acl_shrinker = {
129 .count_objects = nfs_access_cache_count,
130 .scan_objects = nfs_access_cache_scan,
131 .seeks = DEFAULT_SEEKS,
132};
133
134/*
135 * Register the NFS filesystems
136 */
137int __init register_nfs_fs(void)
138{
139 int ret;
140
141 ret = register_filesystem(&nfs_fs_type);
142 if (ret < 0)
143 goto error_0;
144
145 ret = register_nfs4_fs();
146 if (ret < 0)
147 goto error_1;
148
149 ret = nfs_register_sysctl();
150 if (ret < 0)
151 goto error_2;
152 ret = register_shrinker(&acl_shrinker, "nfs-acl");
153 if (ret < 0)
154 goto error_3;
155#ifdef CONFIG_NFS_V4_2
156 nfs_ssc_register_ops();
157#endif
158 return 0;
159error_3:
160 nfs_unregister_sysctl();
161error_2:
162 unregister_nfs4_fs();
163error_1:
164 unregister_filesystem(&nfs_fs_type);
165error_0:
166 return ret;
167}
168
169/*
170 * Unregister the NFS filesystems
171 */
172void __exit unregister_nfs_fs(void)
173{
174 unregister_shrinker(&acl_shrinker);
175 nfs_unregister_sysctl();
176 unregister_nfs4_fs();
177#ifdef CONFIG_NFS_V4_2
178 nfs_ssc_unregister_ops();
179#endif
180 unregister_filesystem(&nfs_fs_type);
181}
182
183bool nfs_sb_active(struct super_block *sb)
184{
185 struct nfs_server *server = NFS_SB(sb);
186
187 if (!atomic_inc_not_zero(&sb->s_active))
188 return false;
189 if (atomic_inc_return(&server->active) != 1)
190 atomic_dec(&sb->s_active);
191 return true;
192}
193EXPORT_SYMBOL_GPL(nfs_sb_active);
194
195void nfs_sb_deactive(struct super_block *sb)
196{
197 struct nfs_server *server = NFS_SB(sb);
198
199 if (atomic_dec_and_test(&server->active))
200 deactivate_super(sb);
201}
202EXPORT_SYMBOL_GPL(nfs_sb_deactive);
203
204static int __nfs_list_for_each_server(struct list_head *head,
205 int (*fn)(struct nfs_server *, void *),
206 void *data)
207{
208 struct nfs_server *server, *last = NULL;
209 int ret = 0;
210
211 rcu_read_lock();
212 list_for_each_entry_rcu(server, head, client_link) {
213 if (!(server->super && nfs_sb_active(server->super)))
214 continue;
215 rcu_read_unlock();
216 if (last)
217 nfs_sb_deactive(last->super);
218 last = server;
219 ret = fn(server, data);
220 if (ret)
221 goto out;
222 rcu_read_lock();
223 }
224 rcu_read_unlock();
225out:
226 if (last)
227 nfs_sb_deactive(last->super);
228 return ret;
229}
230
231int nfs_client_for_each_server(struct nfs_client *clp,
232 int (*fn)(struct nfs_server *, void *),
233 void *data)
234{
235 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data);
236}
237EXPORT_SYMBOL_GPL(nfs_client_for_each_server);
238
239/*
240 * Deliver file system statistics to userspace
241 */
242int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
243{
244 struct nfs_server *server = NFS_SB(dentry->d_sb);
245 unsigned char blockbits;
246 unsigned long blockres;
247 struct nfs_fh *fh = NFS_FH(d_inode(dentry));
248 struct nfs_fsstat res;
249 int error = -ENOMEM;
250
251 res.fattr = nfs_alloc_fattr();
252 if (res.fattr == NULL)
253 goto out_err;
254
255 error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
256 if (unlikely(error == -ESTALE)) {
257 struct dentry *pd_dentry;
258
259 pd_dentry = dget_parent(dentry);
260 nfs_zap_caches(d_inode(pd_dentry));
261 dput(pd_dentry);
262 }
263 nfs_free_fattr(res.fattr);
264 if (error < 0)
265 goto out_err;
266
267 buf->f_type = NFS_SUPER_MAGIC;
268
269 /*
270 * Current versions of glibc do not correctly handle the
271 * case where f_frsize != f_bsize. Eventually we want to
272 * report the value of wtmult in this field.
273 */
274 buf->f_frsize = dentry->d_sb->s_blocksize;
275
276 /*
277 * On most *nix systems, f_blocks, f_bfree, and f_bavail
278 * are reported in units of f_frsize. Linux hasn't had
279 * an f_frsize field in its statfs struct until recently,
280 * thus historically Linux's sys_statfs reports these
281 * fields in units of f_bsize.
282 */
283 buf->f_bsize = dentry->d_sb->s_blocksize;
284 blockbits = dentry->d_sb->s_blocksize_bits;
285 blockres = (1 << blockbits) - 1;
286 buf->f_blocks = (res.tbytes + blockres) >> blockbits;
287 buf->f_bfree = (res.fbytes + blockres) >> blockbits;
288 buf->f_bavail = (res.abytes + blockres) >> blockbits;
289
290 buf->f_files = res.tfiles;
291 buf->f_ffree = res.afiles;
292
293 buf->f_namelen = server->namelen;
294
295 return 0;
296
297 out_err:
298 dprintk("%s: statfs error = %d\n", __func__, -error);
299 return error;
300}
301EXPORT_SYMBOL_GPL(nfs_statfs);
302
303/*
304 * Map the security flavour number to a name
305 */
306static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
307{
308 static const struct {
309 rpc_authflavor_t flavour;
310 const char *str;
311 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
312 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
313 { RPC_AUTH_NULL, "null" },
314 { RPC_AUTH_UNIX, "sys" },
315 { RPC_AUTH_GSS_KRB5, "krb5" },
316 { RPC_AUTH_GSS_KRB5I, "krb5i" },
317 { RPC_AUTH_GSS_KRB5P, "krb5p" },
318 { RPC_AUTH_GSS_LKEY, "lkey" },
319 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
320 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
321 { RPC_AUTH_GSS_SPKM, "spkm" },
322 { RPC_AUTH_GSS_SPKMI, "spkmi" },
323 { RPC_AUTH_GSS_SPKMP, "spkmp" },
324 { UINT_MAX, "unknown" }
325 };
326 int i;
327
328 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
329 if (sec_flavours[i].flavour == flavour)
330 break;
331 }
332 return sec_flavours[i].str;
333}
334
335static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
336 int showdefaults)
337{
338 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
339 char *proto = NULL;
340
341 switch (sap->sa_family) {
342 case AF_INET:
343 switch (nfss->mountd_protocol) {
344 case IPPROTO_UDP:
345 proto = RPCBIND_NETID_UDP;
346 break;
347 case IPPROTO_TCP:
348 proto = RPCBIND_NETID_TCP;
349 break;
350 }
351 break;
352 case AF_INET6:
353 switch (nfss->mountd_protocol) {
354 case IPPROTO_UDP:
355 proto = RPCBIND_NETID_UDP6;
356 break;
357 case IPPROTO_TCP:
358 proto = RPCBIND_NETID_TCP6;
359 break;
360 }
361 break;
362 }
363 if (proto || showdefaults)
364 seq_printf(m, ",mountproto=%s", proto ?: "auto");
365}
366
367static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
368 int showdefaults)
369{
370 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
371
372 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
373 return;
374
375 switch (sap->sa_family) {
376 case AF_INET: {
377 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
378 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
379 break;
380 }
381 case AF_INET6: {
382 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
383 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
384 break;
385 }
386 default:
387 if (showdefaults)
388 seq_puts(m, ",mountaddr=unspecified");
389 }
390
391 if (nfss->mountd_version || showdefaults)
392 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
393 if ((nfss->mountd_port &&
394 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
395 showdefaults)
396 seq_printf(m, ",mountport=%u", nfss->mountd_port);
397
398 nfs_show_mountd_netid(m, nfss, showdefaults);
399}
400
401#if IS_ENABLED(CONFIG_NFS_V4)
402static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
403 int showdefaults)
404{
405 struct nfs_client *clp = nfss->nfs_client;
406
407 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
408}
409#else
410static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
411 int showdefaults)
412{
413}
414#endif
415
416static void nfs_show_nfs_version(struct seq_file *m,
417 unsigned int version,
418 unsigned int minorversion)
419{
420 seq_printf(m, ",vers=%u", version);
421 if (version == 4)
422 seq_printf(m, ".%u", minorversion);
423}
424
425/*
426 * Describe the mount options in force on this server representation
427 */
428static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
429 int showdefaults)
430{
431 static const struct proc_nfs_info {
432 int flag;
433 const char *str;
434 const char *nostr;
435 } nfs_info[] = {
436 { NFS_MOUNT_SOFT, ",soft", "" },
437 { NFS_MOUNT_SOFTERR, ",softerr", "" },
438 { NFS_MOUNT_SOFTREVAL, ",softreval", "" },
439 { NFS_MOUNT_POSIX, ",posix", "" },
440 { NFS_MOUNT_NOCTO, ",nocto", "" },
441 { NFS_MOUNT_NOAC, ",noac", "" },
442 { NFS_MOUNT_NONLM, ",nolock", "" },
443 { NFS_MOUNT_NOACL, ",noacl", "" },
444 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
445 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
446 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
447 { 0, NULL, NULL }
448 };
449 const struct proc_nfs_info *nfs_infop;
450 struct nfs_client *clp = nfss->nfs_client;
451 u32 version = clp->rpc_ops->version;
452 int local_flock, local_fcntl;
453
454 nfs_show_nfs_version(m, version, clp->cl_minorversion);
455 seq_printf(m, ",rsize=%u", nfss->rsize);
456 seq_printf(m, ",wsize=%u", nfss->wsize);
457 if (nfss->bsize != 0)
458 seq_printf(m, ",bsize=%u", nfss->bsize);
459 seq_printf(m, ",namlen=%u", nfss->namelen);
460 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
461 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
462 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
463 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
464 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
465 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
466 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
467 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
468 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
469 seq_puts(m, ",hard");
470 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
471 if (nfss->flags & nfs_infop->flag)
472 seq_puts(m, nfs_infop->str);
473 else
474 seq_puts(m, nfs_infop->nostr);
475 }
476 rcu_read_lock();
477 seq_printf(m, ",proto=%s",
478 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
479 rcu_read_unlock();
480 if (clp->cl_nconnect > 0)
481 seq_printf(m, ",nconnect=%u", clp->cl_nconnect);
482 if (version == 4) {
483 if (clp->cl_max_connect > 1)
484 seq_printf(m, ",max_connect=%u", clp->cl_max_connect);
485 if (nfss->port != NFS_PORT)
486 seq_printf(m, ",port=%u", nfss->port);
487 } else
488 if (nfss->port)
489 seq_printf(m, ",port=%u", nfss->port);
490
491 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
492 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
493 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
494
495 if (version != 4)
496 nfs_show_mountd_options(m, nfss, showdefaults);
497 else
498 nfs_show_nfsv4_options(m, nfss, showdefaults);
499
500 if (nfss->options & NFS_OPTION_FSCACHE)
501 seq_puts(m, ",fsc");
502
503 if (nfss->options & NFS_OPTION_MIGRATION)
504 seq_puts(m, ",migration");
505
506 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
507 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
508 seq_puts(m, ",lookupcache=none");
509 else
510 seq_puts(m, ",lookupcache=pos");
511 }
512
513 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
514 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
515
516 if (!local_flock && !local_fcntl)
517 seq_puts(m, ",local_lock=none");
518 else if (local_flock && local_fcntl)
519 seq_puts(m, ",local_lock=all");
520 else if (local_flock)
521 seq_puts(m, ",local_lock=flock");
522 else
523 seq_puts(m, ",local_lock=posix");
524
525 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) {
526 if (nfss->flags & NFS_MOUNT_WRITE_WAIT)
527 seq_puts(m, ",write=wait");
528 else
529 seq_puts(m, ",write=eager");
530 }
531}
532
533/*
534 * Describe the mount options on this VFS mountpoint
535 */
536int nfs_show_options(struct seq_file *m, struct dentry *root)
537{
538 struct nfs_server *nfss = NFS_SB(root->d_sb);
539
540 nfs_show_mount_options(m, nfss, 0);
541
542 rcu_read_lock();
543 seq_printf(m, ",addr=%s",
544 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
545 RPC_DISPLAY_ADDR));
546 rcu_read_unlock();
547
548 return 0;
549}
550EXPORT_SYMBOL_GPL(nfs_show_options);
551
552#if IS_ENABLED(CONFIG_NFS_V4)
553static void show_lease(struct seq_file *m, struct nfs_server *server)
554{
555 struct nfs_client *clp = server->nfs_client;
556 unsigned long expire;
557
558 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ);
559 expire = clp->cl_last_renewal + clp->cl_lease_time;
560 seq_printf(m, ",lease_expired=%ld",
561 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ);
562}
563#ifdef CONFIG_NFS_V4_1
564static void show_sessions(struct seq_file *m, struct nfs_server *server)
565{
566 if (nfs4_has_session(server->nfs_client))
567 seq_puts(m, ",sessions");
568}
569#else
570static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
571#endif
572#endif
573
574#ifdef CONFIG_NFS_V4_1
575static void show_pnfs(struct seq_file *m, struct nfs_server *server)
576{
577 seq_printf(m, ",pnfs=");
578 if (server->pnfs_curr_ld)
579 seq_printf(m, "%s", server->pnfs_curr_ld->name);
580 else
581 seq_printf(m, "not configured");
582}
583
584static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
585{
586 if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
587 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
588 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
589 "date='%llu,%u'",
590 impl_id->name, impl_id->domain,
591 impl_id->date.seconds, impl_id->date.nseconds);
592 }
593}
594#else
595#if IS_ENABLED(CONFIG_NFS_V4)
596static void show_pnfs(struct seq_file *m, struct nfs_server *server)
597{
598}
599#endif
600static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
601{
602}
603#endif
604
605int nfs_show_devname(struct seq_file *m, struct dentry *root)
606{
607 char *page = (char *) __get_free_page(GFP_KERNEL);
608 char *devname, *dummy;
609 int err = 0;
610 if (!page)
611 return -ENOMEM;
612 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
613 if (IS_ERR(devname))
614 err = PTR_ERR(devname);
615 else
616 seq_escape(m, devname, " \t\n\\");
617 free_page((unsigned long)page);
618 return err;
619}
620EXPORT_SYMBOL_GPL(nfs_show_devname);
621
622int nfs_show_path(struct seq_file *m, struct dentry *dentry)
623{
624 seq_puts(m, "/");
625 return 0;
626}
627EXPORT_SYMBOL_GPL(nfs_show_path);
628
629/*
630 * Present statistical information for this VFS mountpoint
631 */
632int nfs_show_stats(struct seq_file *m, struct dentry *root)
633{
634 int i, cpu;
635 struct nfs_server *nfss = NFS_SB(root->d_sb);
636 struct rpc_auth *auth = nfss->client->cl_auth;
637 struct nfs_iostats totals = { };
638
639 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
640
641 /*
642 * Display all mount option settings
643 */
644 seq_puts(m, "\n\topts:\t");
645 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
646 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
647 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
648 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
649 nfs_show_mount_options(m, nfss, 1);
650
651 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
652
653 show_implementation_id(m, nfss);
654
655 seq_puts(m, "\n\tcaps:\t");
656 seq_printf(m, "caps=0x%x", nfss->caps);
657 seq_printf(m, ",wtmult=%u", nfss->wtmult);
658 seq_printf(m, ",dtsize=%u", nfss->dtsize);
659 seq_printf(m, ",bsize=%u", nfss->bsize);
660 seq_printf(m, ",namlen=%u", nfss->namelen);
661
662#if IS_ENABLED(CONFIG_NFS_V4)
663 if (nfss->nfs_client->rpc_ops->version == 4) {
664 seq_puts(m, "\n\tnfsv4:\t");
665 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
666 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
667 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
668 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
669 show_sessions(m, nfss);
670 show_pnfs(m, nfss);
671 show_lease(m, nfss);
672 }
673#endif
674
675 /*
676 * Display security flavor in effect for this mount
677 */
678 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
679 if (auth->au_flavor)
680 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
681
682 /*
683 * Display superblock I/O counters
684 */
685 for_each_possible_cpu(cpu) {
686 struct nfs_iostats *stats;
687
688 preempt_disable();
689 stats = per_cpu_ptr(nfss->io_stats, cpu);
690
691 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
692 totals.events[i] += stats->events[i];
693 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
694 totals.bytes[i] += stats->bytes[i];
695#ifdef CONFIG_NFS_FSCACHE
696 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
697 totals.fscache[i] += stats->fscache[i];
698#endif
699
700 preempt_enable();
701 }
702
703 seq_puts(m, "\n\tevents:\t");
704 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
705 seq_printf(m, "%lu ", totals.events[i]);
706 seq_puts(m, "\n\tbytes:\t");
707 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
708 seq_printf(m, "%Lu ", totals.bytes[i]);
709#ifdef CONFIG_NFS_FSCACHE
710 if (nfss->options & NFS_OPTION_FSCACHE) {
711 seq_puts(m, "\n\tfsc:\t");
712 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
713 seq_printf(m, "%Lu ", totals.fscache[i]);
714 }
715#endif
716 seq_putc(m, '\n');
717
718 rpc_clnt_show_stats(m, nfss->client);
719
720 return 0;
721}
722EXPORT_SYMBOL_GPL(nfs_show_stats);
723
724/*
725 * Begin unmount by attempting to remove all automounted mountpoints we added
726 * in response to xdev traversals and referrals
727 */
728void nfs_umount_begin(struct super_block *sb)
729{
730 struct nfs_server *server;
731 struct rpc_clnt *rpc;
732
733 server = NFS_SB(sb);
734 /* -EIO all pending I/O */
735 rpc = server->client_acl;
736 if (!IS_ERR(rpc))
737 rpc_killall_tasks(rpc);
738 rpc = server->client;
739 if (!IS_ERR(rpc))
740 rpc_killall_tasks(rpc);
741}
742EXPORT_SYMBOL_GPL(nfs_umount_begin);
743
744/*
745 * Return true if 'match' is in auth_info or auth_info is empty.
746 * Return false otherwise.
747 */
748bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
749 rpc_authflavor_t match)
750{
751 int i;
752
753 if (!auth_info->flavor_len)
754 return true;
755
756 for (i = 0; i < auth_info->flavor_len; i++) {
757 if (auth_info->flavors[i] == match)
758 return true;
759 }
760 return false;
761}
762EXPORT_SYMBOL_GPL(nfs_auth_info_match);
763
764/*
765 * Ensure that a specified authtype in ctx->auth_info is supported by
766 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and
767 * -EACCES if not.
768 */
769static int nfs_verify_authflavors(struct nfs_fs_context *ctx,
770 rpc_authflavor_t *server_authlist,
771 unsigned int count)
772{
773 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
774 bool found_auth_null = false;
775 unsigned int i;
776
777 /*
778 * If the sec= mount option is used, the specified flavor or AUTH_NULL
779 * must be in the list returned by the server.
780 *
781 * AUTH_NULL has a special meaning when it's in the server list - it
782 * means that the server will ignore the rpc creds, so any flavor
783 * can be used but still use the sec= that was specified.
784 *
785 * Note also that the MNT procedure in MNTv1 does not return a list
786 * of supported security flavors. In this case, nfs_mount() fabricates
787 * a security flavor list containing just AUTH_NULL.
788 */
789 for (i = 0; i < count; i++) {
790 flavor = server_authlist[i];
791
792 if (nfs_auth_info_match(&ctx->auth_info, flavor))
793 goto out;
794
795 if (flavor == RPC_AUTH_NULL)
796 found_auth_null = true;
797 }
798
799 if (found_auth_null) {
800 flavor = ctx->auth_info.flavors[0];
801 goto out;
802 }
803
804 dfprintk(MOUNT,
805 "NFS: specified auth flavors not supported by server\n");
806 return -EACCES;
807
808out:
809 ctx->selected_flavor = flavor;
810 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor);
811 return 0;
812}
813
814/*
815 * Use the remote server's MOUNT service to request the NFS file handle
816 * corresponding to the provided path.
817 */
818static int nfs_request_mount(struct fs_context *fc,
819 struct nfs_fh *root_fh,
820 rpc_authflavor_t *server_authlist,
821 unsigned int *server_authlist_len)
822{
823 struct nfs_fs_context *ctx = nfs_fc2context(fc);
824 struct nfs_mount_request request = {
825 .sap = &ctx->mount_server._address,
826 .dirpath = ctx->nfs_server.export_path,
827 .protocol = ctx->mount_server.protocol,
828 .fh = root_fh,
829 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT,
830 .auth_flav_len = server_authlist_len,
831 .auth_flavs = server_authlist,
832 .net = fc->net_ns,
833 };
834 int status;
835
836 if (ctx->mount_server.version == 0) {
837 switch (ctx->version) {
838 default:
839 ctx->mount_server.version = NFS_MNT3_VERSION;
840 break;
841 case 2:
842 ctx->mount_server.version = NFS_MNT_VERSION;
843 }
844 }
845 request.version = ctx->mount_server.version;
846
847 if (ctx->mount_server.hostname)
848 request.hostname = ctx->mount_server.hostname;
849 else
850 request.hostname = ctx->nfs_server.hostname;
851
852 /*
853 * Construct the mount server's address.
854 */
855 if (ctx->mount_server.address.sa_family == AF_UNSPEC) {
856 memcpy(request.sap, &ctx->nfs_server._address,
857 ctx->nfs_server.addrlen);
858 ctx->mount_server.addrlen = ctx->nfs_server.addrlen;
859 }
860 request.salen = ctx->mount_server.addrlen;
861 nfs_set_port(request.sap, &ctx->mount_server.port, 0);
862
863 /*
864 * Now ask the mount server to map our export path
865 * to a file handle.
866 */
867 status = nfs_mount(&request, ctx->timeo, ctx->retrans);
868 if (status != 0) {
869 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
870 request.hostname, status);
871 return status;
872 }
873
874 return 0;
875}
876
877static struct nfs_server *nfs_try_mount_request(struct fs_context *fc)
878{
879 struct nfs_fs_context *ctx = nfs_fc2context(fc);
880 int status;
881 unsigned int i;
882 bool tried_auth_unix = false;
883 bool auth_null_in_list = false;
884 struct nfs_server *server = ERR_PTR(-EACCES);
885 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
886 unsigned int authlist_len = ARRAY_SIZE(authlist);
887
888 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len);
889 if (status)
890 return ERR_PTR(status);
891
892 /*
893 * Was a sec= authflavor specified in the options? First, verify
894 * whether the server supports it, and then just try to use it if so.
895 */
896 if (ctx->auth_info.flavor_len > 0) {
897 status = nfs_verify_authflavors(ctx, authlist, authlist_len);
898 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
899 ctx->selected_flavor);
900 if (status)
901 return ERR_PTR(status);
902 return ctx->nfs_mod->rpc_ops->create_server(fc);
903 }
904
905 /*
906 * No sec= option was provided. RFC 2623, section 2.7 suggests we
907 * SHOULD prefer the flavor listed first. However, some servers list
908 * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
909 */
910 for (i = 0; i < authlist_len; ++i) {
911 rpc_authflavor_t flavor;
912 struct rpcsec_gss_info info;
913
914 flavor = authlist[i];
915 switch (flavor) {
916 case RPC_AUTH_UNIX:
917 tried_auth_unix = true;
918 break;
919 case RPC_AUTH_NULL:
920 auth_null_in_list = true;
921 continue;
922 default:
923 if (rpcauth_get_gssinfo(flavor, &info) != 0)
924 continue;
925 break;
926 }
927 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
928 ctx->selected_flavor = flavor;
929 server = ctx->nfs_mod->rpc_ops->create_server(fc);
930 if (!IS_ERR(server))
931 return server;
932 }
933
934 /*
935 * Nothing we tried so far worked. At this point, give up if we've
936 * already tried AUTH_UNIX or if the server's list doesn't contain
937 * AUTH_NULL
938 */
939 if (tried_auth_unix || !auth_null_in_list)
940 return server;
941
942 /* Last chance! Try AUTH_UNIX */
943 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
944 ctx->selected_flavor = RPC_AUTH_UNIX;
945 return ctx->nfs_mod->rpc_ops->create_server(fc);
946}
947
948int nfs_try_get_tree(struct fs_context *fc)
949{
950 struct nfs_fs_context *ctx = nfs_fc2context(fc);
951
952 if (ctx->need_mount)
953 ctx->server = nfs_try_mount_request(fc);
954 else
955 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc);
956
957 return nfs_get_tree_common(fc);
958}
959EXPORT_SYMBOL_GPL(nfs_try_get_tree);
960
961
962#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
963 | NFS_MOUNT_SECURE \
964 | NFS_MOUNT_TCP \
965 | NFS_MOUNT_VER3 \
966 | NFS_MOUNT_KERBEROS \
967 | NFS_MOUNT_NONLM \
968 | NFS_MOUNT_BROKEN_SUID \
969 | NFS_MOUNT_STRICTLOCK \
970 | NFS_MOUNT_LEGACY_INTERFACE)
971
972#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
973 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
974
975static int
976nfs_compare_remount_data(struct nfs_server *nfss,
977 struct nfs_fs_context *ctx)
978{
979 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
980 ctx->rsize != nfss->rsize ||
981 ctx->wsize != nfss->wsize ||
982 ctx->version != nfss->nfs_client->rpc_ops->version ||
983 ctx->minorversion != nfss->nfs_client->cl_minorversion ||
984 ctx->retrans != nfss->client->cl_timeout->to_retries ||
985 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) ||
986 ctx->acregmin != nfss->acregmin / HZ ||
987 ctx->acregmax != nfss->acregmax / HZ ||
988 ctx->acdirmin != nfss->acdirmin / HZ ||
989 ctx->acdirmax != nfss->acdirmax / HZ ||
990 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
991 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) ||
992 ctx->nfs_server.port != nfss->port ||
993 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
994 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address,
995 (struct sockaddr *)&nfss->nfs_client->cl_addr))
996 return -EINVAL;
997
998 return 0;
999}
1000
1001int nfs_reconfigure(struct fs_context *fc)
1002{
1003 struct nfs_fs_context *ctx = nfs_fc2context(fc);
1004 struct super_block *sb = fc->root->d_sb;
1005 struct nfs_server *nfss = sb->s_fs_info;
1006 int ret;
1007
1008 sync_filesystem(sb);
1009
1010 /*
1011 * Userspace mount programs that send binary options generally send
1012 * them populated with default values. We have no way to know which
1013 * ones were explicitly specified. Fall back to legacy behavior and
1014 * just return success.
1015 */
1016 if (ctx->skip_reconfig_option_check)
1017 return 0;
1018
1019 /*
1020 * noac is a special case. It implies -o sync, but that's not
1021 * necessarily reflected in the mtab options. reconfigure_super
1022 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
1023 * remount options, so we have to explicitly reset it.
1024 */
1025 if (ctx->flags & NFS_MOUNT_NOAC) {
1026 fc->sb_flags |= SB_SYNCHRONOUS;
1027 fc->sb_flags_mask |= SB_SYNCHRONOUS;
1028 }
1029
1030 /* compare new mount options with old ones */
1031 ret = nfs_compare_remount_data(nfss, ctx);
1032 if (ret)
1033 return ret;
1034
1035 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root)));
1036}
1037EXPORT_SYMBOL_GPL(nfs_reconfigure);
1038
1039/*
1040 * Finish setting up an NFS superblock
1041 */
1042static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx)
1043{
1044 struct nfs_server *server = NFS_SB(sb);
1045
1046 sb->s_blocksize_bits = 0;
1047 sb->s_blocksize = 0;
1048 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
1049 sb->s_op = server->nfs_client->cl_nfs_mod->sops;
1050 if (ctx->bsize)
1051 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits);
1052
1053 switch (server->nfs_client->rpc_ops->version) {
1054 case 2:
1055 sb->s_time_gran = 1000;
1056 sb->s_time_min = 0;
1057 sb->s_time_max = U32_MAX;
1058 break;
1059 case 3:
1060 /*
1061 * The VFS shouldn't apply the umask to mode bits.
1062 * We will do so ourselves when necessary.
1063 */
1064 sb->s_flags |= SB_POSIXACL;
1065 sb->s_time_gran = 1;
1066 sb->s_time_min = 0;
1067 sb->s_time_max = U32_MAX;
1068 sb->s_export_op = &nfs_export_ops;
1069 break;
1070 case 4:
1071 sb->s_flags |= SB_POSIXACL;
1072 sb->s_time_gran = 1;
1073 sb->s_time_min = S64_MIN;
1074 sb->s_time_max = S64_MAX;
1075 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1)
1076 sb->s_export_op = &nfs_export_ops;
1077 break;
1078 }
1079
1080 sb->s_magic = NFS_SUPER_MAGIC;
1081
1082 /* We probably want something more informative here */
1083 snprintf(sb->s_id, sizeof(sb->s_id),
1084 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1085
1086 if (sb->s_blocksize == 0)
1087 sb->s_blocksize = nfs_block_bits(server->wsize,
1088 &sb->s_blocksize_bits);
1089
1090 nfs_super_set_maxbytes(sb, server->maxfilesize);
1091 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts;
1092}
1093
1094static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b,
1095 const struct fs_context *fc)
1096{
1097 const struct nfs_server *a = s->s_fs_info;
1098 const struct rpc_clnt *clnt_a = a->client;
1099 const struct rpc_clnt *clnt_b = b->client;
1100
1101 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK))
1102 goto Ebusy;
1103 if (a->nfs_client != b->nfs_client)
1104 goto Ebusy;
1105 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
1106 goto Ebusy;
1107 if (a->wsize != b->wsize)
1108 goto Ebusy;
1109 if (a->rsize != b->rsize)
1110 goto Ebusy;
1111 if (a->acregmin != b->acregmin)
1112 goto Ebusy;
1113 if (a->acregmax != b->acregmax)
1114 goto Ebusy;
1115 if (a->acdirmin != b->acdirmin)
1116 goto Ebusy;
1117 if (a->acdirmax != b->acdirmax)
1118 goto Ebusy;
1119 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1120 goto Ebusy;
1121 return 1;
1122Ebusy:
1123 return 0;
1124}
1125
1126static int nfs_set_super(struct super_block *s, struct fs_context *fc)
1127{
1128 struct nfs_server *server = fc->s_fs_info;
1129 int ret;
1130
1131 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
1132 ret = set_anon_super(s, server);
1133 if (ret == 0)
1134 server->s_dev = s->s_dev;
1135 return ret;
1136}
1137
1138static int nfs_compare_super_address(struct nfs_server *server1,
1139 struct nfs_server *server2)
1140{
1141 struct sockaddr *sap1, *sap2;
1142 struct rpc_xprt *xprt1 = server1->client->cl_xprt;
1143 struct rpc_xprt *xprt2 = server2->client->cl_xprt;
1144
1145 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
1146 return 0;
1147
1148 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1149 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1150
1151 if (sap1->sa_family != sap2->sa_family)
1152 return 0;
1153
1154 switch (sap1->sa_family) {
1155 case AF_INET: {
1156 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1157 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1158 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1159 return 0;
1160 if (sin1->sin_port != sin2->sin_port)
1161 return 0;
1162 break;
1163 }
1164 case AF_INET6: {
1165 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1166 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1167 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1168 return 0;
1169 if (sin1->sin6_port != sin2->sin6_port)
1170 return 0;
1171 break;
1172 }
1173 default:
1174 return 0;
1175 }
1176
1177 return 1;
1178}
1179
1180static int nfs_compare_userns(const struct nfs_server *old,
1181 const struct nfs_server *new)
1182{
1183 const struct user_namespace *oldns = &init_user_ns;
1184 const struct user_namespace *newns = &init_user_ns;
1185
1186 if (old->client && old->client->cl_cred)
1187 oldns = old->client->cl_cred->user_ns;
1188 if (new->client && new->client->cl_cred)
1189 newns = new->client->cl_cred->user_ns;
1190 if (oldns != newns)
1191 return 0;
1192 return 1;
1193}
1194
1195static int nfs_compare_super(struct super_block *sb, struct fs_context *fc)
1196{
1197 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb);
1198
1199 if (!nfs_compare_super_address(old, server))
1200 return 0;
1201 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1202 if (old->flags & NFS_MOUNT_UNSHARED)
1203 return 0;
1204 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1205 return 0;
1206 if (!nfs_compare_userns(old, server))
1207 return 0;
1208 if ((old->has_sec_mnt_opts || fc->security) &&
1209 security_sb_mnt_opts_compat(sb, fc->security))
1210 return 0;
1211 return nfs_compare_mount_options(sb, server, fc);
1212}
1213
1214#ifdef CONFIG_NFS_FSCACHE
1215static int nfs_get_cache_cookie(struct super_block *sb,
1216 struct nfs_fs_context *ctx)
1217{
1218 struct nfs_server *nfss = NFS_SB(sb);
1219 char *uniq = NULL;
1220 int ulen = 0;
1221
1222 nfss->fscache = NULL;
1223
1224 if (!ctx)
1225 return 0;
1226
1227 if (ctx->clone_data.sb) {
1228 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb);
1229 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
1230 return 0;
1231 if (mnt_s->fscache_uniq) {
1232 uniq = mnt_s->fscache_uniq;
1233 ulen = strlen(uniq);
1234 }
1235 } else {
1236 if (!(ctx->options & NFS_OPTION_FSCACHE))
1237 return 0;
1238 if (ctx->fscache_uniq) {
1239 uniq = ctx->fscache_uniq;
1240 ulen = strlen(ctx->fscache_uniq);
1241 }
1242 }
1243
1244 return nfs_fscache_get_super_cookie(sb, uniq, ulen);
1245}
1246#else
1247static int nfs_get_cache_cookie(struct super_block *sb,
1248 struct nfs_fs_context *ctx)
1249{
1250 return 0;
1251}
1252#endif
1253
1254int nfs_get_tree_common(struct fs_context *fc)
1255{
1256 struct nfs_fs_context *ctx = nfs_fc2context(fc);
1257 struct super_block *s;
1258 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super;
1259 struct nfs_server *server = ctx->server;
1260 int error;
1261
1262 ctx->server = NULL;
1263 if (IS_ERR(server))
1264 return PTR_ERR(server);
1265
1266 if (server->flags & NFS_MOUNT_UNSHARED)
1267 compare_super = NULL;
1268
1269 /* -o noac implies -o sync */
1270 if (server->flags & NFS_MOUNT_NOAC)
1271 fc->sb_flags |= SB_SYNCHRONOUS;
1272
1273 if (ctx->clone_data.sb)
1274 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS)
1275 fc->sb_flags |= SB_SYNCHRONOUS;
1276
1277 if (server->caps & NFS_CAP_SECURITY_LABEL)
1278 fc->lsm_flags |= SECURITY_LSM_NATIVE_LABELS;
1279
1280 /* Get a superblock - note that we may end up sharing one that already exists */
1281 fc->s_fs_info = server;
1282 s = sget_fc(fc, compare_super, nfs_set_super);
1283 fc->s_fs_info = NULL;
1284 if (IS_ERR(s)) {
1285 error = PTR_ERR(s);
1286 nfs_errorf(fc, "NFS: Couldn't get superblock");
1287 goto out_err_nosb;
1288 }
1289
1290 if (s->s_fs_info != server) {
1291 nfs_free_server(server);
1292 server = NULL;
1293 } else {
1294 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
1295 MINOR(server->s_dev));
1296 if (error)
1297 goto error_splat_super;
1298 s->s_bdi->io_pages = server->rpages;
1299 server->super = s;
1300 }
1301
1302 if (!s->s_root) {
1303 unsigned bsize = ctx->clone_data.inherited_bsize;
1304 /* initial superblock/root creation */
1305 nfs_fill_super(s, ctx);
1306 if (bsize) {
1307 s->s_blocksize_bits = bsize;
1308 s->s_blocksize = 1U << bsize;
1309 }
1310 error = nfs_get_cache_cookie(s, ctx);
1311 if (error < 0)
1312 goto error_splat_super;
1313 }
1314
1315 error = nfs_get_root(s, fc);
1316 if (error < 0) {
1317 nfs_errorf(fc, "NFS: Couldn't get root dentry");
1318 goto error_splat_super;
1319 }
1320
1321 s->s_flags |= SB_ACTIVE;
1322 error = 0;
1323
1324out:
1325 return error;
1326
1327out_err_nosb:
1328 nfs_free_server(server);
1329 goto out;
1330error_splat_super:
1331 deactivate_locked_super(s);
1332 goto out;
1333}
1334
1335/*
1336 * Destroy an NFS2/3 superblock
1337 */
1338void nfs_kill_super(struct super_block *s)
1339{
1340 struct nfs_server *server = NFS_SB(s);
1341 dev_t dev = s->s_dev;
1342
1343 generic_shutdown_super(s);
1344
1345 nfs_fscache_release_super_cookie(s);
1346
1347 nfs_free_server(server);
1348 free_anon_bdev(dev);
1349}
1350EXPORT_SYMBOL_GPL(nfs_kill_super);
1351
1352#if IS_ENABLED(CONFIG_NFS_V4)
1353
1354/*
1355 * NFS v4 module parameters need to stay in the
1356 * NFS client for backwards compatibility
1357 */
1358unsigned int nfs_callback_set_tcpport;
1359unsigned short nfs_callback_nr_threads;
1360/* Default cache timeout is 10 minutes */
1361unsigned int nfs_idmap_cache_timeout = 600;
1362/* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
1363bool nfs4_disable_idmapping = true;
1364unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
1365unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
1366unsigned short send_implementation_id = 1;
1367char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
1368bool recover_lost_locks = false;
1369
1370EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
1371EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
1372EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
1373EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
1374EXPORT_SYMBOL_GPL(max_session_slots);
1375EXPORT_SYMBOL_GPL(max_session_cb_slots);
1376EXPORT_SYMBOL_GPL(send_implementation_id);
1377EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
1378EXPORT_SYMBOL_GPL(recover_lost_locks);
1379
1380#define NFS_CALLBACK_MAXPORTNR (65535U)
1381
1382static int param_set_portnr(const char *val, const struct kernel_param *kp)
1383{
1384 unsigned long num;
1385 int ret;
1386
1387 if (!val)
1388 return -EINVAL;
1389 ret = kstrtoul(val, 0, &num);
1390 if (ret || num > NFS_CALLBACK_MAXPORTNR)
1391 return -EINVAL;
1392 *((unsigned int *)kp->arg) = num;
1393 return 0;
1394}
1395static const struct kernel_param_ops param_ops_portnr = {
1396 .set = param_set_portnr,
1397 .get = param_get_uint,
1398};
1399#define param_check_portnr(name, p) __param_check(name, p, unsigned int)
1400
1401module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
1402module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
1403MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
1404 "assigned to the NFSv4 callback channels.");
1405module_param(nfs_idmap_cache_timeout, int, 0644);
1406module_param(nfs4_disable_idmapping, bool, 0644);
1407module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
1408 NFS4_CLIENT_ID_UNIQ_LEN, 0600);
1409MODULE_PARM_DESC(nfs4_disable_idmapping,
1410 "Turn off NFSv4 idmapping when using 'sec=sys'");
1411module_param(max_session_slots, ushort, 0644);
1412MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
1413 "requests the client will negotiate");
1414module_param(max_session_cb_slots, ushort, 0644);
1415MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
1416 "callbacks the client will process for a given server");
1417module_param(send_implementation_id, ushort, 0644);
1418MODULE_PARM_DESC(send_implementation_id,
1419 "Send implementation ID with NFSv4.1 exchange_id");
1420MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
1421
1422module_param(recover_lost_locks, bool, 0644);
1423MODULE_PARM_DESC(recover_lost_locks,
1424 "If the server reports that a lock might be lost, "
1425 "try to recover it risking data corruption.");
1426
1427
1428#endif /* CONFIG_NFS_V4 */
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/slab.h>
51#include <net/ipv6.h>
52#include <linux/netdevice.h>
53#include <linux/nfs_xdr.h>
54#include <linux/magic.h>
55#include <linux/parser.h>
56#include <linux/nsproxy.h>
57#include <linux/rcupdate.h>
58
59#include <linux/uaccess.h>
60#include <linux/nfs_ssc.h>
61
62#include <uapi/linux/tls.h>
63
64#include "nfs4_fs.h"
65#include "callback.h"
66#include "delegation.h"
67#include "iostat.h"
68#include "internal.h"
69#include "fscache.h"
70#include "nfs4session.h"
71#include "pnfs.h"
72#include "nfs.h"
73#include "netns.h"
74#include "sysfs.h"
75
76#define NFSDBG_FACILITY NFSDBG_VFS
77
78const struct super_operations nfs_sops = {
79 .alloc_inode = nfs_alloc_inode,
80 .free_inode = nfs_free_inode,
81 .write_inode = nfs_write_inode,
82 .drop_inode = nfs_drop_inode,
83 .statfs = nfs_statfs,
84 .evict_inode = nfs_evict_inode,
85 .umount_begin = nfs_umount_begin,
86 .show_options = nfs_show_options,
87 .show_devname = nfs_show_devname,
88 .show_path = nfs_show_path,
89 .show_stats = nfs_show_stats,
90};
91EXPORT_SYMBOL_GPL(nfs_sops);
92
93#ifdef CONFIG_NFS_V4_2
94static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = {
95 .sco_sb_deactive = nfs_sb_deactive,
96};
97#endif
98
99#if IS_ENABLED(CONFIG_NFS_V4)
100static int __init register_nfs4_fs(void)
101{
102 return register_filesystem(&nfs4_fs_type);
103}
104
105static void unregister_nfs4_fs(void)
106{
107 unregister_filesystem(&nfs4_fs_type);
108}
109#else
110static int __init register_nfs4_fs(void)
111{
112 return 0;
113}
114
115static void unregister_nfs4_fs(void)
116{
117}
118#endif
119
120#ifdef CONFIG_NFS_V4_2
121static void nfs_ssc_register_ops(void)
122{
123 nfs_ssc_register(&nfs_ssc_clnt_ops_tbl);
124}
125
126static void nfs_ssc_unregister_ops(void)
127{
128 nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl);
129}
130#endif /* CONFIG_NFS_V4_2 */
131
132static struct shrinker *acl_shrinker;
133
134/*
135 * Register the NFS filesystems
136 */
137int __init register_nfs_fs(void)
138{
139 int ret;
140
141 ret = register_filesystem(&nfs_fs_type);
142 if (ret < 0)
143 goto error_0;
144
145 ret = register_nfs4_fs();
146 if (ret < 0)
147 goto error_1;
148
149 ret = nfs_register_sysctl();
150 if (ret < 0)
151 goto error_2;
152
153 acl_shrinker = shrinker_alloc(0, "nfs-acl");
154 if (!acl_shrinker) {
155 ret = -ENOMEM;
156 goto error_3;
157 }
158
159 acl_shrinker->count_objects = nfs_access_cache_count;
160 acl_shrinker->scan_objects = nfs_access_cache_scan;
161
162 shrinker_register(acl_shrinker);
163
164#ifdef CONFIG_NFS_V4_2
165 nfs_ssc_register_ops();
166#endif
167 return 0;
168error_3:
169 nfs_unregister_sysctl();
170error_2:
171 unregister_nfs4_fs();
172error_1:
173 unregister_filesystem(&nfs_fs_type);
174error_0:
175 return ret;
176}
177
178/*
179 * Unregister the NFS filesystems
180 */
181void __exit unregister_nfs_fs(void)
182{
183 shrinker_free(acl_shrinker);
184 nfs_unregister_sysctl();
185 unregister_nfs4_fs();
186#ifdef CONFIG_NFS_V4_2
187 nfs_ssc_unregister_ops();
188#endif
189 unregister_filesystem(&nfs_fs_type);
190}
191
192bool nfs_sb_active(struct super_block *sb)
193{
194 struct nfs_server *server = NFS_SB(sb);
195
196 if (!atomic_inc_not_zero(&sb->s_active))
197 return false;
198 if (atomic_inc_return(&server->active) != 1)
199 atomic_dec(&sb->s_active);
200 return true;
201}
202EXPORT_SYMBOL_GPL(nfs_sb_active);
203
204void nfs_sb_deactive(struct super_block *sb)
205{
206 struct nfs_server *server = NFS_SB(sb);
207
208 if (atomic_dec_and_test(&server->active))
209 deactivate_super(sb);
210}
211EXPORT_SYMBOL_GPL(nfs_sb_deactive);
212
213static int __nfs_list_for_each_server(struct list_head *head,
214 int (*fn)(struct nfs_server *, void *),
215 void *data)
216{
217 struct nfs_server *server, *last = NULL;
218 int ret = 0;
219
220 rcu_read_lock();
221 list_for_each_entry_rcu(server, head, client_link) {
222 if (!(server->super && nfs_sb_active(server->super)))
223 continue;
224 rcu_read_unlock();
225 if (last)
226 nfs_sb_deactive(last->super);
227 last = server;
228 ret = fn(server, data);
229 if (ret)
230 goto out;
231 rcu_read_lock();
232 }
233 rcu_read_unlock();
234out:
235 if (last)
236 nfs_sb_deactive(last->super);
237 return ret;
238}
239
240int nfs_client_for_each_server(struct nfs_client *clp,
241 int (*fn)(struct nfs_server *, void *),
242 void *data)
243{
244 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data);
245}
246EXPORT_SYMBOL_GPL(nfs_client_for_each_server);
247
248/*
249 * Deliver file system statistics to userspace
250 */
251int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
252{
253 struct nfs_server *server = NFS_SB(dentry->d_sb);
254 unsigned char blockbits;
255 unsigned long blockres;
256 struct nfs_fh *fh = NFS_FH(d_inode(dentry));
257 struct nfs_fsstat res;
258 int error = -ENOMEM;
259
260 res.fattr = nfs_alloc_fattr();
261 if (res.fattr == NULL)
262 goto out_err;
263
264 error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
265 if (unlikely(error == -ESTALE)) {
266 struct dentry *pd_dentry;
267
268 pd_dentry = dget_parent(dentry);
269 nfs_zap_caches(d_inode(pd_dentry));
270 dput(pd_dentry);
271 }
272 nfs_free_fattr(res.fattr);
273 if (error < 0)
274 goto out_err;
275
276 buf->f_type = NFS_SUPER_MAGIC;
277
278 /*
279 * Current versions of glibc do not correctly handle the
280 * case where f_frsize != f_bsize. Eventually we want to
281 * report the value of wtmult in this field.
282 */
283 buf->f_frsize = dentry->d_sb->s_blocksize;
284
285 /*
286 * On most *nix systems, f_blocks, f_bfree, and f_bavail
287 * are reported in units of f_frsize. Linux hasn't had
288 * an f_frsize field in its statfs struct until recently,
289 * thus historically Linux's sys_statfs reports these
290 * fields in units of f_bsize.
291 */
292 buf->f_bsize = dentry->d_sb->s_blocksize;
293 blockbits = dentry->d_sb->s_blocksize_bits;
294 blockres = (1 << blockbits) - 1;
295 buf->f_blocks = (res.tbytes + blockres) >> blockbits;
296 buf->f_bfree = (res.fbytes + blockres) >> blockbits;
297 buf->f_bavail = (res.abytes + blockres) >> blockbits;
298
299 buf->f_files = res.tfiles;
300 buf->f_ffree = res.afiles;
301
302 buf->f_namelen = server->namelen;
303
304 return 0;
305
306 out_err:
307 dprintk("%s: statfs error = %d\n", __func__, -error);
308 return error;
309}
310EXPORT_SYMBOL_GPL(nfs_statfs);
311
312/*
313 * Map the security flavour number to a name
314 */
315static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
316{
317 static const struct {
318 rpc_authflavor_t flavour;
319 const char *str;
320 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
321 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
322 { RPC_AUTH_NULL, "null" },
323 { RPC_AUTH_UNIX, "sys" },
324 { RPC_AUTH_GSS_KRB5, "krb5" },
325 { RPC_AUTH_GSS_KRB5I, "krb5i" },
326 { RPC_AUTH_GSS_KRB5P, "krb5p" },
327 { RPC_AUTH_GSS_LKEY, "lkey" },
328 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
329 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
330 { RPC_AUTH_GSS_SPKM, "spkm" },
331 { RPC_AUTH_GSS_SPKMI, "spkmi" },
332 { RPC_AUTH_GSS_SPKMP, "spkmp" },
333 { UINT_MAX, "unknown" }
334 };
335 int i;
336
337 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
338 if (sec_flavours[i].flavour == flavour)
339 break;
340 }
341 return sec_flavours[i].str;
342}
343
344static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
345 int showdefaults)
346{
347 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
348 char *proto = NULL;
349
350 switch (sap->sa_family) {
351 case AF_INET:
352 switch (nfss->mountd_protocol) {
353 case IPPROTO_UDP:
354 proto = RPCBIND_NETID_UDP;
355 break;
356 case IPPROTO_TCP:
357 proto = RPCBIND_NETID_TCP;
358 break;
359 }
360 break;
361 case AF_INET6:
362 switch (nfss->mountd_protocol) {
363 case IPPROTO_UDP:
364 proto = RPCBIND_NETID_UDP6;
365 break;
366 case IPPROTO_TCP:
367 proto = RPCBIND_NETID_TCP6;
368 break;
369 }
370 break;
371 }
372 if (proto || showdefaults)
373 seq_printf(m, ",mountproto=%s", proto ?: "auto");
374}
375
376static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
377 int showdefaults)
378{
379 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
380
381 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
382 return;
383
384 switch (sap->sa_family) {
385 case AF_INET: {
386 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
387 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
388 break;
389 }
390 case AF_INET6: {
391 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
392 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
393 break;
394 }
395 default:
396 if (showdefaults)
397 seq_puts(m, ",mountaddr=unspecified");
398 }
399
400 if (nfss->mountd_version || showdefaults)
401 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
402 if ((nfss->mountd_port &&
403 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
404 showdefaults)
405 seq_printf(m, ",mountport=%u", nfss->mountd_port);
406
407 nfs_show_mountd_netid(m, nfss, showdefaults);
408}
409
410#if IS_ENABLED(CONFIG_NFS_V4)
411static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
412 int showdefaults)
413{
414 struct nfs_client *clp = nfss->nfs_client;
415
416 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
417}
418#else
419static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
420 int showdefaults)
421{
422}
423#endif
424
425static void nfs_show_nfs_version(struct seq_file *m,
426 unsigned int version,
427 unsigned int minorversion)
428{
429 seq_printf(m, ",vers=%u", version);
430 if (version == 4)
431 seq_printf(m, ".%u", minorversion);
432}
433
434/*
435 * Describe the mount options in force on this server representation
436 */
437static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
438 int showdefaults)
439{
440 static const struct proc_nfs_info {
441 int flag;
442 const char *str;
443 const char *nostr;
444 } nfs_info[] = {
445 { NFS_MOUNT_SOFT, ",soft", "" },
446 { NFS_MOUNT_SOFTERR, ",softerr", "" },
447 { NFS_MOUNT_SOFTREVAL, ",softreval", "" },
448 { NFS_MOUNT_POSIX, ",posix", "" },
449 { NFS_MOUNT_NOCTO, ",nocto", "" },
450 { NFS_MOUNT_NOAC, ",noac", "" },
451 { NFS_MOUNT_NONLM, ",nolock", "" },
452 { NFS_MOUNT_NOACL, ",noacl", "" },
453 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
454 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
455 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
456 { 0, NULL, NULL }
457 };
458 const struct proc_nfs_info *nfs_infop;
459 struct nfs_client *clp = nfss->nfs_client;
460 u32 version = clp->rpc_ops->version;
461 int local_flock, local_fcntl;
462
463 nfs_show_nfs_version(m, version, clp->cl_minorversion);
464 seq_printf(m, ",rsize=%u", nfss->rsize);
465 seq_printf(m, ",wsize=%u", nfss->wsize);
466 if (nfss->bsize != 0)
467 seq_printf(m, ",bsize=%u", nfss->bsize);
468 seq_printf(m, ",namlen=%u", nfss->namelen);
469 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
470 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
471 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
472 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
473 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
474 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
475 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
476 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
477 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
478 seq_puts(m, ",hard");
479 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
480 if (nfss->flags & nfs_infop->flag)
481 seq_puts(m, nfs_infop->str);
482 else
483 seq_puts(m, nfs_infop->nostr);
484 }
485 rcu_read_lock();
486 seq_printf(m, ",proto=%s",
487 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
488 rcu_read_unlock();
489 if (clp->cl_nconnect > 0)
490 seq_printf(m, ",nconnect=%u", clp->cl_nconnect);
491 if (version == 4) {
492 if (clp->cl_max_connect > 1)
493 seq_printf(m, ",max_connect=%u", clp->cl_max_connect);
494 if (nfss->port != NFS_PORT)
495 seq_printf(m, ",port=%u", nfss->port);
496 } else
497 if (nfss->port)
498 seq_printf(m, ",port=%u", nfss->port);
499
500 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
501 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
502 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
503 switch (clp->cl_xprtsec.policy) {
504 case RPC_XPRTSEC_TLS_ANON:
505 seq_puts(m, ",xprtsec=tls");
506 break;
507 case RPC_XPRTSEC_TLS_X509:
508 seq_puts(m, ",xprtsec=mtls");
509 break;
510 default:
511 break;
512 }
513
514 if (version != 4)
515 nfs_show_mountd_options(m, nfss, showdefaults);
516 else
517 nfs_show_nfsv4_options(m, nfss, showdefaults);
518
519 if (nfss->options & NFS_OPTION_FSCACHE) {
520#ifdef CONFIG_NFS_FSCACHE
521 if (nfss->fscache_uniq)
522 seq_printf(m, ",fsc=%s", nfss->fscache_uniq);
523 else
524 seq_puts(m, ",fsc");
525#else
526 seq_puts(m, ",fsc");
527#endif
528 }
529
530 if (nfss->options & NFS_OPTION_MIGRATION)
531 seq_puts(m, ",migration");
532
533 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
534 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
535 seq_puts(m, ",lookupcache=none");
536 else
537 seq_puts(m, ",lookupcache=pos");
538 }
539
540 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
541 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
542
543 if (!local_flock && !local_fcntl)
544 seq_puts(m, ",local_lock=none");
545 else if (local_flock && local_fcntl)
546 seq_puts(m, ",local_lock=all");
547 else if (local_flock)
548 seq_puts(m, ",local_lock=flock");
549 else
550 seq_puts(m, ",local_lock=posix");
551
552 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) {
553 if (nfss->flags & NFS_MOUNT_WRITE_WAIT)
554 seq_puts(m, ",write=wait");
555 else
556 seq_puts(m, ",write=eager");
557 }
558}
559
560/*
561 * Describe the mount options on this VFS mountpoint
562 */
563int nfs_show_options(struct seq_file *m, struct dentry *root)
564{
565 struct nfs_server *nfss = NFS_SB(root->d_sb);
566
567 nfs_show_mount_options(m, nfss, 0);
568
569 rcu_read_lock();
570 seq_printf(m, ",addr=%s",
571 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
572 RPC_DISPLAY_ADDR));
573 rcu_read_unlock();
574
575 return 0;
576}
577EXPORT_SYMBOL_GPL(nfs_show_options);
578
579#if IS_ENABLED(CONFIG_NFS_V4)
580static void show_lease(struct seq_file *m, struct nfs_server *server)
581{
582 struct nfs_client *clp = server->nfs_client;
583 unsigned long expire;
584
585 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ);
586 expire = clp->cl_last_renewal + clp->cl_lease_time;
587 seq_printf(m, ",lease_expired=%ld",
588 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ);
589}
590#ifdef CONFIG_NFS_V4_1
591static void show_sessions(struct seq_file *m, struct nfs_server *server)
592{
593 if (nfs4_has_session(server->nfs_client))
594 seq_puts(m, ",sessions");
595}
596#else
597static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
598#endif
599#endif
600
601#ifdef CONFIG_NFS_V4_1
602static void show_pnfs(struct seq_file *m, struct nfs_server *server)
603{
604 seq_printf(m, ",pnfs=");
605 if (server->pnfs_curr_ld)
606 seq_printf(m, "%s", server->pnfs_curr_ld->name);
607 else
608 seq_printf(m, "not configured");
609}
610
611static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
612{
613 if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
614 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
615 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
616 "date='%llu,%u'",
617 impl_id->name, impl_id->domain,
618 impl_id->date.seconds, impl_id->date.nseconds);
619 }
620}
621#else
622#if IS_ENABLED(CONFIG_NFS_V4)
623static void show_pnfs(struct seq_file *m, struct nfs_server *server)
624{
625}
626#endif
627static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
628{
629}
630#endif
631
632int nfs_show_devname(struct seq_file *m, struct dentry *root)
633{
634 char *page = (char *) __get_free_page(GFP_KERNEL);
635 char *devname, *dummy;
636 int err = 0;
637 if (!page)
638 return -ENOMEM;
639 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
640 if (IS_ERR(devname))
641 err = PTR_ERR(devname);
642 else
643 seq_escape(m, devname, " \t\n\\");
644 free_page((unsigned long)page);
645 return err;
646}
647EXPORT_SYMBOL_GPL(nfs_show_devname);
648
649int nfs_show_path(struct seq_file *m, struct dentry *dentry)
650{
651 seq_puts(m, "/");
652 return 0;
653}
654EXPORT_SYMBOL_GPL(nfs_show_path);
655
656/*
657 * Present statistical information for this VFS mountpoint
658 */
659int nfs_show_stats(struct seq_file *m, struct dentry *root)
660{
661 int i, cpu;
662 struct nfs_server *nfss = NFS_SB(root->d_sb);
663 struct rpc_auth *auth = nfss->client->cl_auth;
664 struct nfs_iostats totals = { };
665
666 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
667
668 /*
669 * Display all mount option settings
670 */
671 seq_puts(m, "\n\topts:\t");
672 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
673 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
674 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
675 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
676 nfs_show_mount_options(m, nfss, 1);
677
678 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
679
680 show_implementation_id(m, nfss);
681
682 seq_puts(m, "\n\tcaps:\t");
683 seq_printf(m, "caps=0x%x", nfss->caps);
684 seq_printf(m, ",wtmult=%u", nfss->wtmult);
685 seq_printf(m, ",dtsize=%u", nfss->dtsize);
686 seq_printf(m, ",bsize=%u", nfss->bsize);
687 seq_printf(m, ",namlen=%u", nfss->namelen);
688
689#if IS_ENABLED(CONFIG_NFS_V4)
690 if (nfss->nfs_client->rpc_ops->version == 4) {
691 seq_puts(m, "\n\tnfsv4:\t");
692 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
693 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
694 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
695 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
696 show_sessions(m, nfss);
697 show_pnfs(m, nfss);
698 show_lease(m, nfss);
699 }
700#endif
701
702 /*
703 * Display security flavor in effect for this mount
704 */
705 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
706 if (auth->au_flavor)
707 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
708
709 /*
710 * Display superblock I/O counters
711 */
712 for_each_possible_cpu(cpu) {
713 struct nfs_iostats *stats;
714
715 preempt_disable();
716 stats = per_cpu_ptr(nfss->io_stats, cpu);
717
718 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
719 totals.events[i] += stats->events[i];
720 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
721 totals.bytes[i] += stats->bytes[i];
722
723 preempt_enable();
724 }
725
726 seq_puts(m, "\n\tevents:\t");
727 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
728 seq_printf(m, "%lu ", totals.events[i]);
729 seq_puts(m, "\n\tbytes:\t");
730 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
731 seq_printf(m, "%Lu ", totals.bytes[i]);
732 seq_putc(m, '\n');
733
734 rpc_clnt_show_stats(m, nfss->client);
735
736 return 0;
737}
738EXPORT_SYMBOL_GPL(nfs_show_stats);
739
740/*
741 * Begin unmount by attempting to remove all automounted mountpoints we added
742 * in response to xdev traversals and referrals
743 */
744void nfs_umount_begin(struct super_block *sb)
745{
746 struct nfs_server *server;
747 struct rpc_clnt *rpc;
748
749 server = NFS_SB(sb);
750 /* -EIO all pending I/O */
751 rpc = server->client_acl;
752 if (!IS_ERR(rpc))
753 rpc_killall_tasks(rpc);
754 rpc = server->client;
755 if (!IS_ERR(rpc))
756 rpc_killall_tasks(rpc);
757}
758EXPORT_SYMBOL_GPL(nfs_umount_begin);
759
760/*
761 * Return true if 'match' is in auth_info or auth_info is empty.
762 * Return false otherwise.
763 */
764bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
765 rpc_authflavor_t match)
766{
767 int i;
768
769 if (!auth_info->flavor_len)
770 return true;
771
772 for (i = 0; i < auth_info->flavor_len; i++) {
773 if (auth_info->flavors[i] == match)
774 return true;
775 }
776 return false;
777}
778EXPORT_SYMBOL_GPL(nfs_auth_info_match);
779
780/*
781 * Ensure that a specified authtype in ctx->auth_info is supported by
782 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and
783 * -EACCES if not.
784 */
785static int nfs_verify_authflavors(struct nfs_fs_context *ctx,
786 rpc_authflavor_t *server_authlist,
787 unsigned int count)
788{
789 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
790 bool found_auth_null = false;
791 unsigned int i;
792
793 /*
794 * If the sec= mount option is used, the specified flavor or AUTH_NULL
795 * must be in the list returned by the server.
796 *
797 * AUTH_NULL has a special meaning when it's in the server list - it
798 * means that the server will ignore the rpc creds, so any flavor
799 * can be used but still use the sec= that was specified.
800 *
801 * Note also that the MNT procedure in MNTv1 does not return a list
802 * of supported security flavors. In this case, nfs_mount() fabricates
803 * a security flavor list containing just AUTH_NULL.
804 */
805 for (i = 0; i < count; i++) {
806 flavor = server_authlist[i];
807
808 if (nfs_auth_info_match(&ctx->auth_info, flavor))
809 goto out;
810
811 if (flavor == RPC_AUTH_NULL)
812 found_auth_null = true;
813 }
814
815 if (found_auth_null) {
816 flavor = ctx->auth_info.flavors[0];
817 goto out;
818 }
819
820 dfprintk(MOUNT,
821 "NFS: specified auth flavors not supported by server\n");
822 return -EACCES;
823
824out:
825 ctx->selected_flavor = flavor;
826 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor);
827 return 0;
828}
829
830/*
831 * Use the remote server's MOUNT service to request the NFS file handle
832 * corresponding to the provided path.
833 */
834static int nfs_request_mount(struct fs_context *fc,
835 struct nfs_fh *root_fh,
836 rpc_authflavor_t *server_authlist,
837 unsigned int *server_authlist_len)
838{
839 struct nfs_fs_context *ctx = nfs_fc2context(fc);
840 struct nfs_mount_request request = {
841 .sap = &ctx->mount_server._address,
842 .dirpath = ctx->nfs_server.export_path,
843 .protocol = ctx->mount_server.protocol,
844 .fh = root_fh,
845 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT,
846 .auth_flav_len = server_authlist_len,
847 .auth_flavs = server_authlist,
848 .net = fc->net_ns,
849 };
850 int status;
851
852 if (ctx->mount_server.version == 0) {
853 switch (ctx->version) {
854 default:
855 ctx->mount_server.version = NFS_MNT3_VERSION;
856 break;
857 case 2:
858 ctx->mount_server.version = NFS_MNT_VERSION;
859 }
860 }
861 request.version = ctx->mount_server.version;
862
863 if (ctx->mount_server.hostname)
864 request.hostname = ctx->mount_server.hostname;
865 else
866 request.hostname = ctx->nfs_server.hostname;
867
868 /*
869 * Construct the mount server's address.
870 */
871 if (ctx->mount_server.address.sa_family == AF_UNSPEC) {
872 memcpy(request.sap, &ctx->nfs_server._address,
873 ctx->nfs_server.addrlen);
874 ctx->mount_server.addrlen = ctx->nfs_server.addrlen;
875 }
876 request.salen = ctx->mount_server.addrlen;
877 nfs_set_port(request.sap, &ctx->mount_server.port, 0);
878
879 /*
880 * Now ask the mount server to map our export path
881 * to a file handle.
882 */
883 status = nfs_mount(&request, ctx->timeo, ctx->retrans);
884 if (status != 0) {
885 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
886 request.hostname, status);
887 return status;
888 }
889
890 return 0;
891}
892
893static struct nfs_server *nfs_try_mount_request(struct fs_context *fc)
894{
895 struct nfs_fs_context *ctx = nfs_fc2context(fc);
896 int status;
897 unsigned int i;
898 bool tried_auth_unix = false;
899 bool auth_null_in_list = false;
900 struct nfs_server *server = ERR_PTR(-EACCES);
901 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
902 unsigned int authlist_len = ARRAY_SIZE(authlist);
903
904 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len);
905 if (status)
906 return ERR_PTR(status);
907
908 /*
909 * Was a sec= authflavor specified in the options? First, verify
910 * whether the server supports it, and then just try to use it if so.
911 */
912 if (ctx->auth_info.flavor_len > 0) {
913 status = nfs_verify_authflavors(ctx, authlist, authlist_len);
914 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
915 ctx->selected_flavor);
916 if (status)
917 return ERR_PTR(status);
918 return ctx->nfs_mod->rpc_ops->create_server(fc);
919 }
920
921 /*
922 * No sec= option was provided. RFC 2623, section 2.7 suggests we
923 * SHOULD prefer the flavor listed first. However, some servers list
924 * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
925 */
926 for (i = 0; i < authlist_len; ++i) {
927 rpc_authflavor_t flavor;
928 struct rpcsec_gss_info info;
929
930 flavor = authlist[i];
931 switch (flavor) {
932 case RPC_AUTH_UNIX:
933 tried_auth_unix = true;
934 break;
935 case RPC_AUTH_NULL:
936 auth_null_in_list = true;
937 continue;
938 default:
939 if (rpcauth_get_gssinfo(flavor, &info) != 0)
940 continue;
941 break;
942 }
943 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
944 ctx->selected_flavor = flavor;
945 server = ctx->nfs_mod->rpc_ops->create_server(fc);
946 if (!IS_ERR(server))
947 return server;
948 }
949
950 /*
951 * Nothing we tried so far worked. At this point, give up if we've
952 * already tried AUTH_UNIX or if the server's list doesn't contain
953 * AUTH_NULL
954 */
955 if (tried_auth_unix || !auth_null_in_list)
956 return server;
957
958 /* Last chance! Try AUTH_UNIX */
959 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
960 ctx->selected_flavor = RPC_AUTH_UNIX;
961 return ctx->nfs_mod->rpc_ops->create_server(fc);
962}
963
964int nfs_try_get_tree(struct fs_context *fc)
965{
966 struct nfs_fs_context *ctx = nfs_fc2context(fc);
967
968 if (ctx->need_mount)
969 ctx->server = nfs_try_mount_request(fc);
970 else
971 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc);
972
973 return nfs_get_tree_common(fc);
974}
975EXPORT_SYMBOL_GPL(nfs_try_get_tree);
976
977
978#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
979 | NFS_MOUNT_SECURE \
980 | NFS_MOUNT_TCP \
981 | NFS_MOUNT_VER3 \
982 | NFS_MOUNT_KERBEROS \
983 | NFS_MOUNT_NONLM \
984 | NFS_MOUNT_BROKEN_SUID \
985 | NFS_MOUNT_STRICTLOCK \
986 | NFS_MOUNT_LEGACY_INTERFACE)
987
988#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
989 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
990
991static int
992nfs_compare_remount_data(struct nfs_server *nfss,
993 struct nfs_fs_context *ctx)
994{
995 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
996 ctx->rsize != nfss->rsize ||
997 ctx->wsize != nfss->wsize ||
998 ctx->version != nfss->nfs_client->rpc_ops->version ||
999 ctx->minorversion != nfss->nfs_client->cl_minorversion ||
1000 ctx->retrans != nfss->client->cl_timeout->to_retries ||
1001 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) ||
1002 ctx->acregmin != nfss->acregmin / HZ ||
1003 ctx->acregmax != nfss->acregmax / HZ ||
1004 ctx->acdirmin != nfss->acdirmin / HZ ||
1005 ctx->acdirmax != nfss->acdirmax / HZ ||
1006 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1007 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) ||
1008 ctx->nfs_server.port != nfss->port ||
1009 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1010 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address,
1011 (struct sockaddr *)&nfss->nfs_client->cl_addr))
1012 return -EINVAL;
1013
1014 return 0;
1015}
1016
1017int nfs_reconfigure(struct fs_context *fc)
1018{
1019 struct nfs_fs_context *ctx = nfs_fc2context(fc);
1020 struct super_block *sb = fc->root->d_sb;
1021 struct nfs_server *nfss = sb->s_fs_info;
1022 int ret;
1023
1024 sync_filesystem(sb);
1025
1026 /*
1027 * Userspace mount programs that send binary options generally send
1028 * them populated with default values. We have no way to know which
1029 * ones were explicitly specified. Fall back to legacy behavior and
1030 * just return success.
1031 */
1032 if (ctx->skip_reconfig_option_check)
1033 return 0;
1034
1035 /*
1036 * noac is a special case. It implies -o sync, but that's not
1037 * necessarily reflected in the mtab options. reconfigure_super
1038 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
1039 * remount options, so we have to explicitly reset it.
1040 */
1041 if (ctx->flags & NFS_MOUNT_NOAC) {
1042 fc->sb_flags |= SB_SYNCHRONOUS;
1043 fc->sb_flags_mask |= SB_SYNCHRONOUS;
1044 }
1045
1046 /* compare new mount options with old ones */
1047 ret = nfs_compare_remount_data(nfss, ctx);
1048 if (ret)
1049 return ret;
1050
1051 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root)));
1052}
1053EXPORT_SYMBOL_GPL(nfs_reconfigure);
1054
1055/*
1056 * Finish setting up an NFS superblock
1057 */
1058static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx)
1059{
1060 struct nfs_server *server = NFS_SB(sb);
1061
1062 sb->s_blocksize_bits = 0;
1063 sb->s_blocksize = 0;
1064 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
1065 sb->s_op = server->nfs_client->cl_nfs_mod->sops;
1066 if (ctx->bsize)
1067 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits);
1068
1069 switch (server->nfs_client->rpc_ops->version) {
1070 case 2:
1071 sb->s_time_gran = 1000;
1072 sb->s_time_min = 0;
1073 sb->s_time_max = U32_MAX;
1074 break;
1075 case 3:
1076 /*
1077 * The VFS shouldn't apply the umask to mode bits.
1078 * We will do so ourselves when necessary.
1079 */
1080 sb->s_flags |= SB_POSIXACL;
1081 sb->s_time_gran = 1;
1082 sb->s_time_min = 0;
1083 sb->s_time_max = U32_MAX;
1084 sb->s_export_op = &nfs_export_ops;
1085 break;
1086 case 4:
1087 sb->s_iflags |= SB_I_NOUMASK;
1088 sb->s_time_gran = 1;
1089 sb->s_time_min = S64_MIN;
1090 sb->s_time_max = S64_MAX;
1091 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1)
1092 sb->s_export_op = &nfs_export_ops;
1093 break;
1094 }
1095
1096 sb->s_magic = NFS_SUPER_MAGIC;
1097
1098 /* We probably want something more informative here */
1099 snprintf(sb->s_id, sizeof(sb->s_id),
1100 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1101
1102 if (sb->s_blocksize == 0)
1103 sb->s_blocksize = nfs_block_bits(server->wsize,
1104 &sb->s_blocksize_bits);
1105
1106 nfs_super_set_maxbytes(sb, server->maxfilesize);
1107 nfs_sysfs_move_server_to_sb(sb);
1108 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts;
1109}
1110
1111static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b,
1112 const struct fs_context *fc)
1113{
1114 const struct nfs_server *a = s->s_fs_info;
1115 const struct rpc_clnt *clnt_a = a->client;
1116 const struct rpc_clnt *clnt_b = b->client;
1117
1118 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK))
1119 goto Ebusy;
1120 if (a->nfs_client != b->nfs_client)
1121 goto Ebusy;
1122 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
1123 goto Ebusy;
1124 if (a->wsize != b->wsize)
1125 goto Ebusy;
1126 if (a->rsize != b->rsize)
1127 goto Ebusy;
1128 if (a->acregmin != b->acregmin)
1129 goto Ebusy;
1130 if (a->acregmax != b->acregmax)
1131 goto Ebusy;
1132 if (a->acdirmin != b->acdirmin)
1133 goto Ebusy;
1134 if (a->acdirmax != b->acdirmax)
1135 goto Ebusy;
1136 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1137 goto Ebusy;
1138 return 1;
1139Ebusy:
1140 return 0;
1141}
1142
1143static int nfs_set_super(struct super_block *s, struct fs_context *fc)
1144{
1145 struct nfs_server *server = fc->s_fs_info;
1146 int ret;
1147
1148 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
1149 ret = set_anon_super(s, server);
1150 if (ret == 0)
1151 server->s_dev = s->s_dev;
1152 return ret;
1153}
1154
1155static int nfs_compare_super_address(struct nfs_server *server1,
1156 struct nfs_server *server2)
1157{
1158 struct sockaddr *sap1, *sap2;
1159 struct rpc_xprt *xprt1 = server1->client->cl_xprt;
1160 struct rpc_xprt *xprt2 = server2->client->cl_xprt;
1161
1162 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
1163 return 0;
1164
1165 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1166 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1167
1168 if (sap1->sa_family != sap2->sa_family)
1169 return 0;
1170
1171 switch (sap1->sa_family) {
1172 case AF_INET: {
1173 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1174 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1175 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1176 return 0;
1177 if (sin1->sin_port != sin2->sin_port)
1178 return 0;
1179 break;
1180 }
1181 case AF_INET6: {
1182 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1183 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1184 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1185 return 0;
1186 if (sin1->sin6_port != sin2->sin6_port)
1187 return 0;
1188 break;
1189 }
1190 default:
1191 return 0;
1192 }
1193
1194 return 1;
1195}
1196
1197static int nfs_compare_userns(const struct nfs_server *old,
1198 const struct nfs_server *new)
1199{
1200 const struct user_namespace *oldns = &init_user_ns;
1201 const struct user_namespace *newns = &init_user_ns;
1202
1203 if (old->client && old->client->cl_cred)
1204 oldns = old->client->cl_cred->user_ns;
1205 if (new->client && new->client->cl_cred)
1206 newns = new->client->cl_cred->user_ns;
1207 if (oldns != newns)
1208 return 0;
1209 return 1;
1210}
1211
1212static int nfs_compare_super(struct super_block *sb, struct fs_context *fc)
1213{
1214 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb);
1215
1216 if (!nfs_compare_super_address(old, server))
1217 return 0;
1218 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1219 if (old->flags & NFS_MOUNT_UNSHARED)
1220 return 0;
1221 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1222 return 0;
1223 if (!nfs_compare_userns(old, server))
1224 return 0;
1225 if ((old->has_sec_mnt_opts || fc->security) &&
1226 security_sb_mnt_opts_compat(sb, fc->security))
1227 return 0;
1228 return nfs_compare_mount_options(sb, server, fc);
1229}
1230
1231#ifdef CONFIG_NFS_FSCACHE
1232static int nfs_get_cache_cookie(struct super_block *sb,
1233 struct nfs_fs_context *ctx)
1234{
1235 struct nfs_server *nfss = NFS_SB(sb);
1236 char *uniq = NULL;
1237 int ulen = 0;
1238
1239 nfss->fscache = NULL;
1240
1241 if (!ctx)
1242 return 0;
1243
1244 if (ctx->clone_data.sb) {
1245 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb);
1246 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
1247 return 0;
1248 if (mnt_s->fscache_uniq) {
1249 uniq = mnt_s->fscache_uniq;
1250 ulen = strlen(uniq);
1251 }
1252 } else {
1253 if (!(ctx->options & NFS_OPTION_FSCACHE))
1254 return 0;
1255 if (ctx->fscache_uniq) {
1256 uniq = ctx->fscache_uniq;
1257 ulen = strlen(ctx->fscache_uniq);
1258 }
1259 }
1260
1261 return nfs_fscache_get_super_cookie(sb, uniq, ulen);
1262}
1263#else
1264static int nfs_get_cache_cookie(struct super_block *sb,
1265 struct nfs_fs_context *ctx)
1266{
1267 return 0;
1268}
1269#endif
1270
1271int nfs_get_tree_common(struct fs_context *fc)
1272{
1273 struct nfs_fs_context *ctx = nfs_fc2context(fc);
1274 struct super_block *s;
1275 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super;
1276 struct nfs_server *server = ctx->server;
1277 int error;
1278
1279 ctx->server = NULL;
1280 if (IS_ERR(server))
1281 return PTR_ERR(server);
1282
1283 if (server->flags & NFS_MOUNT_UNSHARED)
1284 compare_super = NULL;
1285
1286 /* -o noac implies -o sync */
1287 if (server->flags & NFS_MOUNT_NOAC)
1288 fc->sb_flags |= SB_SYNCHRONOUS;
1289
1290 if (ctx->clone_data.sb)
1291 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS)
1292 fc->sb_flags |= SB_SYNCHRONOUS;
1293
1294 /* Get a superblock - note that we may end up sharing one that already exists */
1295 fc->s_fs_info = server;
1296 s = sget_fc(fc, compare_super, nfs_set_super);
1297 fc->s_fs_info = NULL;
1298 if (IS_ERR(s)) {
1299 error = PTR_ERR(s);
1300 nfs_errorf(fc, "NFS: Couldn't get superblock");
1301 goto out_err_nosb;
1302 }
1303
1304 if (s->s_fs_info != server) {
1305 nfs_free_server(server);
1306 server = NULL;
1307 } else {
1308 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
1309 MINOR(server->s_dev));
1310 if (error)
1311 goto error_splat_super;
1312 s->s_bdi->io_pages = server->rpages;
1313 server->super = s;
1314 }
1315
1316 if (!s->s_root) {
1317 unsigned bsize = ctx->clone_data.inherited_bsize;
1318 /* initial superblock/root creation */
1319 nfs_fill_super(s, ctx);
1320 if (bsize) {
1321 s->s_blocksize_bits = bsize;
1322 s->s_blocksize = 1U << bsize;
1323 }
1324 error = nfs_get_cache_cookie(s, ctx);
1325 if (error < 0)
1326 goto error_splat_super;
1327 }
1328
1329 error = nfs_get_root(s, fc);
1330 if (error < 0) {
1331 nfs_errorf(fc, "NFS: Couldn't get root dentry");
1332 goto error_splat_super;
1333 }
1334
1335 s->s_flags |= SB_ACTIVE;
1336 error = 0;
1337
1338out:
1339 return error;
1340
1341out_err_nosb:
1342 nfs_free_server(server);
1343 goto out;
1344error_splat_super:
1345 deactivate_locked_super(s);
1346 goto out;
1347}
1348
1349/*
1350 * Destroy an NFS superblock
1351 */
1352void nfs_kill_super(struct super_block *s)
1353{
1354 struct nfs_server *server = NFS_SB(s);
1355
1356 nfs_sysfs_move_sb_to_server(server);
1357 kill_anon_super(s);
1358
1359 nfs_fscache_release_super_cookie(s);
1360
1361 nfs_free_server(server);
1362}
1363EXPORT_SYMBOL_GPL(nfs_kill_super);
1364
1365#if IS_ENABLED(CONFIG_NFS_V4)
1366
1367/*
1368 * NFS v4 module parameters need to stay in the
1369 * NFS client for backwards compatibility
1370 */
1371unsigned int nfs_callback_set_tcpport;
1372unsigned short nfs_callback_nr_threads;
1373/* Default cache timeout is 10 minutes */
1374unsigned int nfs_idmap_cache_timeout = 600;
1375/* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
1376bool nfs4_disable_idmapping = true;
1377unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
1378unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
1379unsigned short send_implementation_id = 1;
1380char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
1381bool recover_lost_locks = false;
1382short nfs_delay_retrans = -1;
1383
1384EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
1385EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
1386EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
1387EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
1388EXPORT_SYMBOL_GPL(max_session_slots);
1389EXPORT_SYMBOL_GPL(max_session_cb_slots);
1390EXPORT_SYMBOL_GPL(send_implementation_id);
1391EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
1392EXPORT_SYMBOL_GPL(recover_lost_locks);
1393EXPORT_SYMBOL_GPL(nfs_delay_retrans);
1394
1395#define NFS_CALLBACK_MAXPORTNR (65535U)
1396
1397static int param_set_portnr(const char *val, const struct kernel_param *kp)
1398{
1399 unsigned long num;
1400 int ret;
1401
1402 if (!val)
1403 return -EINVAL;
1404 ret = kstrtoul(val, 0, &num);
1405 if (ret || num > NFS_CALLBACK_MAXPORTNR)
1406 return -EINVAL;
1407 *((unsigned int *)kp->arg) = num;
1408 return 0;
1409}
1410static const struct kernel_param_ops param_ops_portnr = {
1411 .set = param_set_portnr,
1412 .get = param_get_uint,
1413};
1414#define param_check_portnr(name, p) __param_check(name, p, unsigned int)
1415
1416module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
1417module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
1418MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
1419 "assigned to the NFSv4 callback channels.");
1420module_param(nfs_idmap_cache_timeout, int, 0644);
1421module_param(nfs4_disable_idmapping, bool, 0644);
1422module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
1423 NFS4_CLIENT_ID_UNIQ_LEN, 0600);
1424MODULE_PARM_DESC(nfs4_disable_idmapping,
1425 "Turn off NFSv4 idmapping when using 'sec=sys'");
1426module_param(max_session_slots, ushort, 0644);
1427MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
1428 "requests the client will negotiate");
1429module_param(max_session_cb_slots, ushort, 0644);
1430MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
1431 "callbacks the client will process for a given server");
1432module_param(send_implementation_id, ushort, 0644);
1433MODULE_PARM_DESC(send_implementation_id,
1434 "Send implementation ID with NFSv4.1 exchange_id");
1435MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
1436
1437module_param(recover_lost_locks, bool, 0644);
1438MODULE_PARM_DESC(recover_lost_locks,
1439 "If the server reports that a lock might be lost, "
1440 "try to recover it risking data corruption.");
1441
1442module_param_named(delay_retrans, nfs_delay_retrans, short, 0644);
1443MODULE_PARM_DESC(delay_retrans,
1444 "Unless negative, specifies the number of times the NFSv4 "
1445 "client retries a request before returning an EAGAIN error, "
1446 "after a reply of NFS4ERR_DELAY from the server.");
1447#endif /* CONFIG_NFS_V4 */