forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
super.c
1392 lines (1218 loc) · 36.4 KB
/
super.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/fs/nfs/super.c
*
* Copyright (C) 1992 Rick Sladkey
*
* nfs superblock handling functions
*
* Modularised by Alan Cox <[email protected]>, while hacking some
* experimental NFS changes. Modularisation taken straight from SYS5 fs.
*
* Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
*
* Split from inode.c by David Howells <[email protected]>
*
* - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
* particular server are held in the same superblock
* - NFS superblocks can have several effective roots to the dentry tree
* - directory type roots are spliced into the tree when a path from one root reaches the root
* of another (see nfs_lookup())
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/metrics.h>
#include <linux/sunrpc/xprtsock.h>
#include <linux/sunrpc/xprtrdma.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/lockd/bind.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/vfs.h>
#include <linux/inet.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <net/ipv6.h>
#include <linux/netdevice.h>
#include <linux/nfs_xdr.h>
#include <linux/magic.h>
#include <linux/parser.h>
#include <linux/nsproxy.h>
#include <linux/rcupdate.h>
#include <linux/uaccess.h>
#include <linux/nfs_ssc.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "iostat.h"
#include "internal.h"
#include "fscache.h"
#include "nfs4session.h"
#include "pnfs.h"
#include "nfs.h"
#define NFSDBG_FACILITY NFSDBG_VFS
const struct super_operations nfs_sops = {
.alloc_inode = nfs_alloc_inode,
.free_inode = nfs_free_inode,
.write_inode = nfs_write_inode,
.drop_inode = nfs_drop_inode,
.statfs = nfs_statfs,
.evict_inode = nfs_evict_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
.show_devname = nfs_show_devname,
.show_path = nfs_show_path,
.show_stats = nfs_show_stats,
};
EXPORT_SYMBOL_GPL(nfs_sops);
static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = {
.sco_sb_deactive = nfs_sb_deactive,
};
#if IS_ENABLED(CONFIG_NFS_V4)
static int __init register_nfs4_fs(void)
{
return register_filesystem(&nfs4_fs_type);
}
static void unregister_nfs4_fs(void)
{
unregister_filesystem(&nfs4_fs_type);
}
#else
static int __init register_nfs4_fs(void)
{
return 0;
}
static void unregister_nfs4_fs(void)
{
}
#endif
static void nfs_ssc_register_ops(void)
{
nfs_ssc_register(&nfs_ssc_clnt_ops_tbl);
}
static void nfs_ssc_unregister_ops(void)
{
nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl);
}
static struct shrinker acl_shrinker = {
.count_objects = nfs_access_cache_count,
.scan_objects = nfs_access_cache_scan,
.seeks = DEFAULT_SEEKS,
};
/*
* Register the NFS filesystems
*/
int __init register_nfs_fs(void)
{
int ret;
ret = register_filesystem(&nfs_fs_type);
if (ret < 0)
goto error_0;
ret = register_nfs4_fs();
if (ret < 0)
goto error_1;
ret = nfs_register_sysctl();
if (ret < 0)
goto error_2;
ret = register_shrinker(&acl_shrinker);
if (ret < 0)
goto error_3;
nfs_ssc_register_ops();
return 0;
error_3:
nfs_unregister_sysctl();
error_2:
unregister_nfs4_fs();
error_1:
unregister_filesystem(&nfs_fs_type);
error_0:
return ret;
}
/*
* Unregister the NFS filesystems
*/
void __exit unregister_nfs_fs(void)
{
unregister_shrinker(&acl_shrinker);
nfs_unregister_sysctl();
unregister_nfs4_fs();
nfs_ssc_unregister_ops();
unregister_filesystem(&nfs_fs_type);
}
bool nfs_sb_active(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
if (!atomic_inc_not_zero(&sb->s_active))
return false;
if (atomic_inc_return(&server->active) != 1)
atomic_dec(&sb->s_active);
return true;
}
EXPORT_SYMBOL_GPL(nfs_sb_active);
void nfs_sb_deactive(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
if (atomic_dec_and_test(&server->active))
deactivate_super(sb);
}
EXPORT_SYMBOL_GPL(nfs_sb_deactive);
static int __nfs_list_for_each_server(struct list_head *head,
int (*fn)(struct nfs_server *, void *),
void *data)
{
struct nfs_server *server, *last = NULL;
int ret = 0;
rcu_read_lock();
list_for_each_entry_rcu(server, head, client_link) {
if (!(server->super && nfs_sb_active(server->super)))
continue;
rcu_read_unlock();
if (last)
nfs_sb_deactive(last->super);
last = server;
ret = fn(server, data);
if (ret)
goto out;
rcu_read_lock();
}
rcu_read_unlock();
out:
if (last)
nfs_sb_deactive(last->super);
return ret;
}
int nfs_client_for_each_server(struct nfs_client *clp,
int (*fn)(struct nfs_server *, void *),
void *data)
{
return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data);
}
EXPORT_SYMBOL_GPL(nfs_client_for_each_server);
/*
* Deliver file system statistics to userspace
*/
int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct nfs_server *server = NFS_SB(dentry->d_sb);
unsigned char blockbits;
unsigned long blockres;
struct nfs_fh *fh = NFS_FH(d_inode(dentry));
struct nfs_fsstat res;
int error = -ENOMEM;
res.fattr = nfs_alloc_fattr();
if (res.fattr == NULL)
goto out_err;
error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
if (unlikely(error == -ESTALE)) {
struct dentry *pd_dentry;
pd_dentry = dget_parent(dentry);
nfs_zap_caches(d_inode(pd_dentry));
dput(pd_dentry);
}
nfs_free_fattr(res.fattr);
if (error < 0)
goto out_err;
buf->f_type = NFS_SUPER_MAGIC;
/*
* Current versions of glibc do not correctly handle the
* case where f_frsize != f_bsize. Eventually we want to
* report the value of wtmult in this field.
*/
buf->f_frsize = dentry->d_sb->s_blocksize;
/*
* On most *nix systems, f_blocks, f_bfree, and f_bavail
* are reported in units of f_frsize. Linux hasn't had
* an f_frsize field in its statfs struct until recently,
* thus historically Linux's sys_statfs reports these
* fields in units of f_bsize.
*/
buf->f_bsize = dentry->d_sb->s_blocksize;
blockbits = dentry->d_sb->s_blocksize_bits;
blockres = (1 << blockbits) - 1;
buf->f_blocks = (res.tbytes + blockres) >> blockbits;
buf->f_bfree = (res.fbytes + blockres) >> blockbits;
buf->f_bavail = (res.abytes + blockres) >> blockbits;
buf->f_files = res.tfiles;
buf->f_ffree = res.afiles;
buf->f_namelen = server->namelen;
return 0;
out_err:
dprintk("%s: statfs error = %d\n", __func__, -error);
return error;
}
EXPORT_SYMBOL_GPL(nfs_statfs);
/*
* Map the security flavour number to a name
*/
static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
{
static const struct {
rpc_authflavor_t flavour;
const char *str;
} sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
/* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
{ RPC_AUTH_NULL, "null" },
{ RPC_AUTH_UNIX, "sys" },
{ RPC_AUTH_GSS_KRB5, "krb5" },
{ RPC_AUTH_GSS_KRB5I, "krb5i" },
{ RPC_AUTH_GSS_KRB5P, "krb5p" },
{ RPC_AUTH_GSS_LKEY, "lkey" },
{ RPC_AUTH_GSS_LKEYI, "lkeyi" },
{ RPC_AUTH_GSS_LKEYP, "lkeyp" },
{ RPC_AUTH_GSS_SPKM, "spkm" },
{ RPC_AUTH_GSS_SPKMI, "spkmi" },
{ RPC_AUTH_GSS_SPKMP, "spkmp" },
{ UINT_MAX, "unknown" }
};
int i;
for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
if (sec_flavours[i].flavour == flavour)
break;
}
return sec_flavours[i].str;
}
static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
char *proto = NULL;
switch (sap->sa_family) {
case AF_INET:
switch (nfss->mountd_protocol) {
case IPPROTO_UDP:
proto = RPCBIND_NETID_UDP;
break;
case IPPROTO_TCP:
proto = RPCBIND_NETID_TCP;
break;
}
break;
case AF_INET6:
switch (nfss->mountd_protocol) {
case IPPROTO_UDP:
proto = RPCBIND_NETID_UDP6;
break;
case IPPROTO_TCP:
proto = RPCBIND_NETID_TCP6;
break;
}
break;
}
if (proto || showdefaults)
seq_printf(m, ",mountproto=%s", proto ?: "auto");
}
static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
return;
switch (sap->sa_family) {
case AF_INET: {
struct sockaddr_in *sin = (struct sockaddr_in *)sap;
seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
break;
}
case AF_INET6: {
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
break;
}
default:
if (showdefaults)
seq_puts(m, ",mountaddr=unspecified");
}
if (nfss->mountd_version || showdefaults)
seq_printf(m, ",mountvers=%u", nfss->mountd_version);
if ((nfss->mountd_port &&
nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
showdefaults)
seq_printf(m, ",mountport=%u", nfss->mountd_port);
nfs_show_mountd_netid(m, nfss, showdefaults);
}
#if IS_ENABLED(CONFIG_NFS_V4)
static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
struct nfs_client *clp = nfss->nfs_client;
seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
}
#else
static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
}
#endif
static void nfs_show_nfs_version(struct seq_file *m,
unsigned int version,
unsigned int minorversion)
{
seq_printf(m, ",vers=%u", version);
if (version == 4)
seq_printf(m, ".%u", minorversion);
}
/*
* Describe the mount options in force on this server representation
*/
static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
int showdefaults)
{
static const struct proc_nfs_info {
int flag;
const char *str;
const char *nostr;
} nfs_info[] = {
{ NFS_MOUNT_SOFT, ",soft", "" },
{ NFS_MOUNT_SOFTERR, ",softerr", "" },
{ NFS_MOUNT_SOFTREVAL, ",softreval", "" },
{ NFS_MOUNT_POSIX, ",posix", "" },
{ NFS_MOUNT_NOCTO, ",nocto", "" },
{ NFS_MOUNT_NOAC, ",noac", "" },
{ NFS_MOUNT_NONLM, ",nolock", "" },
{ NFS_MOUNT_NOACL, ",noacl", "" },
{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
{ NFS_MOUNT_UNSHARED, ",nosharecache", "" },
{ NFS_MOUNT_NORESVPORT, ",noresvport", "" },
{ 0, NULL, NULL }
};
const struct proc_nfs_info *nfs_infop;
struct nfs_client *clp = nfss->nfs_client;
u32 version = clp->rpc_ops->version;
int local_flock, local_fcntl;
nfs_show_nfs_version(m, version, clp->cl_minorversion);
seq_printf(m, ",rsize=%u", nfss->rsize);
seq_printf(m, ",wsize=%u", nfss->wsize);
if (nfss->bsize != 0)
seq_printf(m, ",bsize=%u", nfss->bsize);
seq_printf(m, ",namlen=%u", nfss->namelen);
if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
seq_puts(m, ",hard");
for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
if (nfss->flags & nfs_infop->flag)
seq_puts(m, nfs_infop->str);
else
seq_puts(m, nfs_infop->nostr);
}
rcu_read_lock();
seq_printf(m, ",proto=%s",
rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
rcu_read_unlock();
if (clp->cl_nconnect > 0)
seq_printf(m, ",nconnect=%u", clp->cl_nconnect);
if (version == 4) {
if (nfss->port != NFS_PORT)
seq_printf(m, ",port=%u", nfss->port);
} else
if (nfss->port)
seq_printf(m, ",port=%u", nfss->port);
seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
if (version != 4)
nfs_show_mountd_options(m, nfss, showdefaults);
else
nfs_show_nfsv4_options(m, nfss, showdefaults);
if (nfss->options & NFS_OPTION_FSCACHE)
seq_puts(m, ",fsc");
if (nfss->options & NFS_OPTION_MIGRATION)
seq_puts(m, ",migration");
if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
seq_puts(m, ",lookupcache=none");
else
seq_puts(m, ",lookupcache=pos");
}
local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
if (!local_flock && !local_fcntl)
seq_puts(m, ",local_lock=none");
else if (local_flock && local_fcntl)
seq_puts(m, ",local_lock=all");
else if (local_flock)
seq_puts(m, ",local_lock=flock");
else
seq_puts(m, ",local_lock=posix");
}
/*
* Describe the mount options on this VFS mountpoint
*/
int nfs_show_options(struct seq_file *m, struct dentry *root)
{
struct nfs_server *nfss = NFS_SB(root->d_sb);
nfs_show_mount_options(m, nfss, 0);
rcu_read_lock();
seq_printf(m, ",addr=%s",
rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
RPC_DISPLAY_ADDR));
rcu_read_unlock();
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_options);
#if IS_ENABLED(CONFIG_NFS_V4)
static void show_lease(struct seq_file *m, struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
unsigned long expire;
seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ);
expire = clp->cl_last_renewal + clp->cl_lease_time;
seq_printf(m, ",lease_expired=%ld",
time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ);
}
#ifdef CONFIG_NFS_V4_1
static void show_sessions(struct seq_file *m, struct nfs_server *server)
{
if (nfs4_has_session(server->nfs_client))
seq_puts(m, ",sessions");
}
#else
static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
#endif
#endif
#ifdef CONFIG_NFS_V4_1
static void show_pnfs(struct seq_file *m, struct nfs_server *server)
{
seq_printf(m, ",pnfs=");
if (server->pnfs_curr_ld)
seq_printf(m, "%s", server->pnfs_curr_ld->name);
else
seq_printf(m, "not configured");
}
static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
{
if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
"date='%llu,%u'",
impl_id->name, impl_id->domain,
impl_id->date.seconds, impl_id->date.nseconds);
}
}
#else
#if IS_ENABLED(CONFIG_NFS_V4)
static void show_pnfs(struct seq_file *m, struct nfs_server *server)
{
}
#endif
static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
{
}
#endif
int nfs_show_devname(struct seq_file *m, struct dentry *root)
{
char *page = (char *) __get_free_page(GFP_KERNEL);
char *devname, *dummy;
int err = 0;
if (!page)
return -ENOMEM;
devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
if (IS_ERR(devname))
err = PTR_ERR(devname);
else
seq_escape(m, devname, " \t\n\\");
free_page((unsigned long)page);
return err;
}
EXPORT_SYMBOL_GPL(nfs_show_devname);
int nfs_show_path(struct seq_file *m, struct dentry *dentry)
{
seq_puts(m, "/");
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_path);
/*
* Present statistical information for this VFS mountpoint
*/
int nfs_show_stats(struct seq_file *m, struct dentry *root)
{
int i, cpu;
struct nfs_server *nfss = NFS_SB(root->d_sb);
struct rpc_auth *auth = nfss->client->cl_auth;
struct nfs_iostats totals = { };
seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
/*
* Display all mount option settings
*/
seq_puts(m, "\n\topts:\t");
seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
nfs_show_mount_options(m, nfss, 1);
seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
show_implementation_id(m, nfss);
seq_puts(m, "\n\tcaps:\t");
seq_printf(m, "caps=0x%x", nfss->caps);
seq_printf(m, ",wtmult=%u", nfss->wtmult);
seq_printf(m, ",dtsize=%u", nfss->dtsize);
seq_printf(m, ",bsize=%u", nfss->bsize);
seq_printf(m, ",namlen=%u", nfss->namelen);
#if IS_ENABLED(CONFIG_NFS_V4)
if (nfss->nfs_client->rpc_ops->version == 4) {
seq_puts(m, "\n\tnfsv4:\t");
seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
show_sessions(m, nfss);
show_pnfs(m, nfss);
show_lease(m, nfss);
}
#endif
/*
* Display security flavor in effect for this mount
*/
seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
if (auth->au_flavor)
seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
/*
* Display superblock I/O counters
*/
for_each_possible_cpu(cpu) {
struct nfs_iostats *stats;
preempt_disable();
stats = per_cpu_ptr(nfss->io_stats, cpu);
for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
totals.events[i] += stats->events[i];
for (i = 0; i < __NFSIOS_BYTESMAX; i++)
totals.bytes[i] += stats->bytes[i];
#ifdef CONFIG_NFS_FSCACHE
for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
totals.fscache[i] += stats->fscache[i];
#endif
preempt_enable();
}
seq_puts(m, "\n\tevents:\t");
for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
seq_printf(m, "%lu ", totals.events[i]);
seq_puts(m, "\n\tbytes:\t");
for (i = 0; i < __NFSIOS_BYTESMAX; i++)
seq_printf(m, "%Lu ", totals.bytes[i]);
#ifdef CONFIG_NFS_FSCACHE
if (nfss->options & NFS_OPTION_FSCACHE) {
seq_puts(m, "\n\tfsc:\t");
for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
seq_printf(m, "%Lu ", totals.fscache[i]);
}
#endif
seq_putc(m, '\n');
rpc_clnt_show_stats(m, nfss->client);
return 0;
}
EXPORT_SYMBOL_GPL(nfs_show_stats);
/*
* Begin unmount by attempting to remove all automounted mountpoints we added
* in response to xdev traversals and referrals
*/
void nfs_umount_begin(struct super_block *sb)
{
struct nfs_server *server;
struct rpc_clnt *rpc;
server = NFS_SB(sb);
/* -EIO all pending I/O */
rpc = server->client_acl;
if (!IS_ERR(rpc))
rpc_killall_tasks(rpc);
rpc = server->client;
if (!IS_ERR(rpc))
rpc_killall_tasks(rpc);
}
EXPORT_SYMBOL_GPL(nfs_umount_begin);
/*
* Return true if 'match' is in auth_info or auth_info is empty.
* Return false otherwise.
*/
bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
rpc_authflavor_t match)
{
int i;
if (!auth_info->flavor_len)
return true;
for (i = 0; i < auth_info->flavor_len; i++) {
if (auth_info->flavors[i] == match)
return true;
}
return false;
}
EXPORT_SYMBOL_GPL(nfs_auth_info_match);
/*
* Ensure that a specified authtype in ctx->auth_info is supported by
* the server. Returns 0 and sets ctx->selected_flavor if it's ok, and
* -EACCES if not.
*/
static int nfs_verify_authflavors(struct nfs_fs_context *ctx,
rpc_authflavor_t *server_authlist,
unsigned int count)
{
rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
bool found_auth_null = false;
unsigned int i;
/*
* If the sec= mount option is used, the specified flavor or AUTH_NULL
* must be in the list returned by the server.
*
* AUTH_NULL has a special meaning when it's in the server list - it
* means that the server will ignore the rpc creds, so any flavor
* can be used but still use the sec= that was specified.
*
* Note also that the MNT procedure in MNTv1 does not return a list
* of supported security flavors. In this case, nfs_mount() fabricates
* a security flavor list containing just AUTH_NULL.
*/
for (i = 0; i < count; i++) {
flavor = server_authlist[i];
if (nfs_auth_info_match(&ctx->auth_info, flavor))
goto out;
if (flavor == RPC_AUTH_NULL)
found_auth_null = true;
}
if (found_auth_null) {
flavor = ctx->auth_info.flavors[0];
goto out;
}
dfprintk(MOUNT,
"NFS: specified auth flavors not supported by server\n");
return -EACCES;
out:
ctx->selected_flavor = flavor;
dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor);
return 0;
}
/*
* Use the remote server's MOUNT service to request the NFS file handle
* corresponding to the provided path.
*/
static int nfs_request_mount(struct fs_context *fc,
struct nfs_fh *root_fh,
rpc_authflavor_t *server_authlist,
unsigned int *server_authlist_len)
{
struct nfs_fs_context *ctx = nfs_fc2context(fc);
struct nfs_mount_request request = {
.sap = (struct sockaddr *)
&ctx->mount_server.address,
.dirpath = ctx->nfs_server.export_path,
.protocol = ctx->mount_server.protocol,
.fh = root_fh,
.noresvport = ctx->flags & NFS_MOUNT_NORESVPORT,
.auth_flav_len = server_authlist_len,
.auth_flavs = server_authlist,
.net = fc->net_ns,
};
int status;
if (ctx->mount_server.version == 0) {
switch (ctx->version) {
default:
ctx->mount_server.version = NFS_MNT3_VERSION;
break;
case 2:
ctx->mount_server.version = NFS_MNT_VERSION;
}
}
request.version = ctx->mount_server.version;
if (ctx->mount_server.hostname)
request.hostname = ctx->mount_server.hostname;
else
request.hostname = ctx->nfs_server.hostname;
/*
* Construct the mount server's address.
*/
if (ctx->mount_server.address.sa_family == AF_UNSPEC) {
memcpy(request.sap, &ctx->nfs_server.address,
ctx->nfs_server.addrlen);
ctx->mount_server.addrlen = ctx->nfs_server.addrlen;
}
request.salen = ctx->mount_server.addrlen;
nfs_set_port(request.sap, &ctx->mount_server.port, 0);
/*
* Now ask the mount server to map our export path
* to a file handle.
*/
status = nfs_mount(&request);
if (status != 0) {
dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
request.hostname, status);
return status;
}
return 0;
}
static struct nfs_server *nfs_try_mount_request(struct fs_context *fc)
{
struct nfs_fs_context *ctx = nfs_fc2context(fc);
int status;
unsigned int i;
bool tried_auth_unix = false;
bool auth_null_in_list = false;
struct nfs_server *server = ERR_PTR(-EACCES);
rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
unsigned int authlist_len = ARRAY_SIZE(authlist);
status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len);
if (status)
return ERR_PTR(status);
/*
* Was a sec= authflavor specified in the options? First, verify
* whether the server supports it, and then just try to use it if so.
*/
if (ctx->auth_info.flavor_len > 0) {
status = nfs_verify_authflavors(ctx, authlist, authlist_len);
dfprintk(MOUNT, "NFS: using auth flavor %u\n",
ctx->selected_flavor);
if (status)
return ERR_PTR(status);
return ctx->nfs_mod->rpc_ops->create_server(fc);
}
/*
* No sec= option was provided. RFC 2623, section 2.7 suggests we
* SHOULD prefer the flavor listed first. However, some servers list
* AUTH_NULL first. Avoid ever choosing AUTH_NULL.
*/
for (i = 0; i < authlist_len; ++i) {
rpc_authflavor_t flavor;
struct rpcsec_gss_info info;
flavor = authlist[i];
switch (flavor) {
case RPC_AUTH_UNIX:
tried_auth_unix = true;
break;
case RPC_AUTH_NULL:
auth_null_in_list = true;
continue;
default:
if (rpcauth_get_gssinfo(flavor, &info) != 0)
continue;
break;
}
dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
ctx->selected_flavor = flavor;
server = ctx->nfs_mod->rpc_ops->create_server(fc);
if (!IS_ERR(server))
return server;
}
/*
* Nothing we tried so far worked. At this point, give up if we've
* already tried AUTH_UNIX or if the server's list doesn't contain
* AUTH_NULL
*/
if (tried_auth_unix || !auth_null_in_list)
return server;
/* Last chance! Try AUTH_UNIX */
dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
ctx->selected_flavor = RPC_AUTH_UNIX;
return ctx->nfs_mod->rpc_ops->create_server(fc);
}
int nfs_try_get_tree(struct fs_context *fc)
{
struct nfs_fs_context *ctx = nfs_fc2context(fc);
if (ctx->need_mount)
ctx->server = nfs_try_mount_request(fc);
else
ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc);
return nfs_get_tree_common(fc);
}
EXPORT_SYMBOL_GPL(nfs_try_get_tree);
#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
| NFS_MOUNT_SECURE \
| NFS_MOUNT_TCP \
| NFS_MOUNT_VER3 \
| NFS_MOUNT_KERBEROS \
| NFS_MOUNT_NONLM \
| NFS_MOUNT_BROKEN_SUID \
| NFS_MOUNT_STRICTLOCK \
| NFS_MOUNT_LEGACY_INTERFACE)
#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
static int
nfs_compare_remount_data(struct nfs_server *nfss,
struct nfs_fs_context *ctx)
{
if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
ctx->rsize != nfss->rsize ||
ctx->wsize != nfss->wsize ||
ctx->version != nfss->nfs_client->rpc_ops->version ||
ctx->minorversion != nfss->nfs_client->cl_minorversion ||
ctx->retrans != nfss->client->cl_timeout->to_retries ||
!nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) ||
ctx->acregmin != nfss->acregmin / HZ ||
ctx->acregmax != nfss->acregmax / HZ ||
ctx->acdirmin != nfss->acdirmin / HZ ||
ctx->acdirmax != nfss->acdirmax / HZ ||
ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
(ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) ||
ctx->nfs_server.port != nfss->port ||
ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
!rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address,
(struct sockaddr *)&nfss->nfs_client->cl_addr))
return -EINVAL;
return 0;
}
int nfs_reconfigure(struct fs_context *fc)
{
struct nfs_fs_context *ctx = nfs_fc2context(fc);
struct super_block *sb = fc->root->d_sb;
struct nfs_server *nfss = sb->s_fs_info;
sync_filesystem(sb);
/*
* Userspace mount programs that send binary options generally send
* them populated with default values. We have no way to know which
* ones were explicitly specified. Fall back to legacy behavior and
* just return success.
*/
if (ctx->skip_reconfig_option_check)
return 0;