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