1 /*
2 * linux/fs/nfs/super.c
3 *
4 * Copyright (C) 1992 Rick Sladkey
5 *
6 * nfs superblock handling functions
7 *
8 * Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
9 * experimental NFS changes. Modularisation taken straight from SYS5 fs.
10 *
11 * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
12 * J.S.Peatfield@damtp.cam.ac.uk
13 *
14 * Split from inode.c by David Howells <dhowells@redhat.com>
15 *
16 * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
17 * particular server are held in the same superblock
18 * - NFS superblocks can have several effective roots to the dentry tree
19 * - directory type roots are spliced into the tree when a path from one root reaches the root
20 * of another (see nfs_lookup())
21 */
22
23 #include <linux/module.h>
24 #include <linux/init.h>
25
26 #include <linux/time.h>
27 #include <linux/kernel.h>
28 #include <linux/mm.h>
29 #include <linux/string.h>
30 #include <linux/stat.h>
31 #include <linux/errno.h>
32 #include <linux/unistd.h>
33 #include <linux/sunrpc/clnt.h>
34 #include <linux/sunrpc/stats.h>
35 #include <linux/sunrpc/metrics.h>
36 #include <linux/sunrpc/xprtsock.h>
37 #include <linux/sunrpc/xprtrdma.h>
38 #include <linux/nfs_fs.h>
39 #include <linux/nfs_mount.h>
40 #include <linux/nfs4_mount.h>
41 #include <linux/lockd/bind.h>
42 #include <linux/smp_lock.h>
43 #include <linux/seq_file.h>
44 #include <linux/mount.h>
45 #include <linux/nfs_idmap.h>
46 #include <linux/vfs.h>
47 #include <linux/inet.h>
48 #include <linux/in6.h>
49 #include <net/ipv6.h>
50 #include <linux/netdevice.h>
51 #include <linux/nfs_xdr.h>
52 #include <linux/magic.h>
53 #include <linux/parser.h>
54
55 #include <asm/system.h>
56 #include <asm/uaccess.h>
57
58 #include "nfs4_fs.h"
59 #include "callback.h"
60 #include "delegation.h"
61 #include "iostat.h"
62 #include "internal.h"
63
64 #define NFSDBG_FACILITY NFSDBG_VFS
65
66 enum {
67 /* Mount options that take no arguments */
68 Opt_soft, Opt_hard,
69 Opt_posix, Opt_noposix,
70 Opt_cto, Opt_nocto,
71 Opt_ac, Opt_noac,
72 Opt_lock, Opt_nolock,
73 Opt_v2, Opt_v3,
74 Opt_udp, Opt_tcp, Opt_rdma,
75 Opt_acl, Opt_noacl,
76 Opt_rdirplus, Opt_nordirplus,
77 Opt_sharecache, Opt_nosharecache,
78 Opt_resvport, Opt_noresvport,
79
80 /* Mount options that take integer arguments */
81 Opt_port,
82 Opt_rsize, Opt_wsize, Opt_bsize,
83 Opt_timeo, Opt_retrans,
84 Opt_acregmin, Opt_acregmax,
85 Opt_acdirmin, Opt_acdirmax,
86 Opt_actimeo,
87 Opt_namelen,
88 Opt_mountport,
89 Opt_mountvers,
90 Opt_nfsvers,
91
92 /* Mount options that take string arguments */
93 Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
94 Opt_addr, Opt_mountaddr, Opt_clientaddr,
95 Opt_lookupcache,
96
97 /* Special mount options */
98 Opt_userspace, Opt_deprecated, Opt_sloppy,
99
100 Opt_err
101 };
102
103 static const match_table_t nfs_mount_option_tokens = {
104 { Opt_userspace, "bg" },
105 { Opt_userspace, "fg" },
106 { Opt_userspace, "retry=%s" },
107
108 { Opt_sloppy, "sloppy" },
109
110 { Opt_soft, "soft" },
111 { Opt_hard, "hard" },
112 { Opt_deprecated, "intr" },
113 { Opt_deprecated, "nointr" },
114 { Opt_posix, "posix" },
115 { Opt_noposix, "noposix" },
116 { Opt_cto, "cto" },
117 { Opt_nocto, "nocto" },
118 { Opt_ac, "ac" },
119 { Opt_noac, "noac" },
120 { Opt_lock, "lock" },
121 { Opt_nolock, "nolock" },
122 { Opt_v2, "v2" },
123 { Opt_v3, "v3" },
124 { Opt_udp, "udp" },
125 { Opt_tcp, "tcp" },
126 { Opt_rdma, "rdma" },
127 { Opt_acl, "acl" },
128 { Opt_noacl, "noacl" },
129 { Opt_rdirplus, "rdirplus" },
130 { Opt_nordirplus, "nordirplus" },
131 { Opt_sharecache, "sharecache" },
132 { Opt_nosharecache, "nosharecache" },
133 { Opt_resvport, "resvport" },
134 { Opt_noresvport, "noresvport" },
135
136 { Opt_port, "port=%u" },
137 { Opt_rsize, "rsize=%u" },
138 { Opt_wsize, "wsize=%u" },
139 { Opt_bsize, "bsize=%u" },
140 { Opt_timeo, "timeo=%u" },
141 { Opt_retrans, "retrans=%u" },
142 { Opt_acregmin, "acregmin=%u" },
143 { Opt_acregmax, "acregmax=%u" },
144 { Opt_acdirmin, "acdirmin=%u" },
145 { Opt_acdirmax, "acdirmax=%u" },
146 { Opt_actimeo, "actimeo=%u" },
147 { Opt_namelen, "namlen=%u" },
148 { Opt_mountport, "mountport=%u" },
149 { Opt_mountvers, "mountvers=%u" },
150 { Opt_nfsvers, "nfsvers=%u" },
151 { Opt_nfsvers, "vers=%u" },
152
153 { Opt_sec, "sec=%s" },
154 { Opt_proto, "proto=%s" },
155 { Opt_mountproto, "mountproto=%s" },
156 { Opt_addr, "addr=%s" },
157 { Opt_clientaddr, "clientaddr=%s" },
158 { Opt_mounthost, "mounthost=%s" },
159 { Opt_mountaddr, "mountaddr=%s" },
160
161 { Opt_lookupcache, "lookupcache=%s" },
162
163 { Opt_err, NULL }
164 };
165
166 enum {
167 Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
168
169 Opt_xprt_err
170 };
171
172 static const match_table_t nfs_xprt_protocol_tokens = {
173 { Opt_xprt_udp, "udp" },
174 { Opt_xprt_tcp, "tcp" },
175 { Opt_xprt_rdma, "rdma" },
176
177 { Opt_xprt_err, NULL }
178 };
179
180 enum {
181 Opt_sec_none, Opt_sec_sys,
182 Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
183 Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
184 Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
185
186 Opt_sec_err
187 };
188
189 static const match_table_t nfs_secflavor_tokens = {
190 { Opt_sec_none, "none" },
191 { Opt_sec_none, "null" },
192 { Opt_sec_sys, "sys" },
193
194 { Opt_sec_krb5, "krb5" },
195 { Opt_sec_krb5i, "krb5i" },
196 { Opt_sec_krb5p, "krb5p" },
197
198 { Opt_sec_lkey, "lkey" },
199 { Opt_sec_lkeyi, "lkeyi" },
200 { Opt_sec_lkeyp, "lkeyp" },
201
202 { Opt_sec_spkm, "spkm3" },
203 { Opt_sec_spkmi, "spkm3i" },
204 { Opt_sec_spkmp, "spkm3p" },
205
206 { Opt_sec_err, NULL }
207 };
208
209 enum {
210 Opt_lookupcache_all, Opt_lookupcache_positive,
211 Opt_lookupcache_none,
212
213 Opt_lookupcache_err
214 };
215
216 static match_table_t nfs_lookupcache_tokens = {
217 { Opt_lookupcache_all, "all" },
218 { Opt_lookupcache_positive, "pos" },
219 { Opt_lookupcache_positive, "positive" },
220 { Opt_lookupcache_none, "none" },
221
222 { Opt_lookupcache_err, NULL }
223 };
224
225
226 static void nfs_umount_begin(struct super_block *);
227 static int nfs_statfs(struct dentry *, struct kstatfs *);
228 static int nfs_show_options(struct seq_file *, struct vfsmount *);
229 static int nfs_show_stats(struct seq_file *, struct vfsmount *);
230 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
231 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
232 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
233 static void nfs_kill_super(struct super_block *);
234 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
235
236 static struct file_system_type nfs_fs_type = {
237 .owner = THIS_MODULE,
238 .name = "nfs",
239 .get_sb = nfs_get_sb,
240 .kill_sb = nfs_kill_super,
241 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
242 };
243
244 struct file_system_type nfs_xdev_fs_type = {
245 .owner = THIS_MODULE,
246 .name = "nfs",
247 .get_sb = nfs_xdev_get_sb,
248 .kill_sb = nfs_kill_super,
249 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
250 };
251
252 static const struct super_operations nfs_sops = {
253 .alloc_inode = nfs_alloc_inode,
254 .destroy_inode = nfs_destroy_inode,
255 .write_inode = nfs_write_inode,
256 .statfs = nfs_statfs,
257 .clear_inode = nfs_clear_inode,
258 .umount_begin = nfs_umount_begin,
259 .show_options = nfs_show_options,
260 .show_stats = nfs_show_stats,
261 .remount_fs = nfs_remount,
262 };
263
264 #ifdef CONFIG_NFS_V4
265 static int nfs4_get_sb(struct file_system_type *fs_type,
266 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
267 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
268 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
269 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
270 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
271 static void nfs4_kill_super(struct super_block *sb);
272
273 static struct file_system_type nfs4_fs_type = {
274 .owner = THIS_MODULE,
275 .name = "nfs4",
276 .get_sb = nfs4_get_sb,
277 .kill_sb = nfs4_kill_super,
278 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
279 };
280
281 struct file_system_type nfs4_xdev_fs_type = {
282 .owner = THIS_MODULE,
283 .name = "nfs4",
284 .get_sb = nfs4_xdev_get_sb,
285 .kill_sb = nfs4_kill_super,
286 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
287 };
288
289 struct file_system_type nfs4_referral_fs_type = {
290 .owner = THIS_MODULE,
291 .name = "nfs4",
292 .get_sb = nfs4_referral_get_sb,
293 .kill_sb = nfs4_kill_super,
294 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
295 };
296
297 static const struct super_operations nfs4_sops = {
298 .alloc_inode = nfs_alloc_inode,
299 .destroy_inode = nfs_destroy_inode,
300 .write_inode = nfs_write_inode,
301 .statfs = nfs_statfs,
302 .clear_inode = nfs4_clear_inode,
303 .umount_begin = nfs_umount_begin,
304 .show_options = nfs_show_options,
305 .show_stats = nfs_show_stats,
306 .remount_fs = nfs_remount,
307 };
308 #endif
309
310 static struct shrinker acl_shrinker = {
311 .shrink = nfs_access_cache_shrinker,
312 .seeks = DEFAULT_SEEKS,
313 };
314
315 /*
316 * Register the NFS filesystems
317 */
register_nfs_fs(void)318 int __init register_nfs_fs(void)
319 {
320 int ret;
321
322 ret = register_filesystem(&nfs_fs_type);
323 if (ret < 0)
324 goto error_0;
325
326 ret = nfs_register_sysctl();
327 if (ret < 0)
328 goto error_1;
329 #ifdef CONFIG_NFS_V4
330 ret = register_filesystem(&nfs4_fs_type);
331 if (ret < 0)
332 goto error_2;
333 #endif
334 register_shrinker(&acl_shrinker);
335 return 0;
336
337 #ifdef CONFIG_NFS_V4
338 error_2:
339 nfs_unregister_sysctl();
340 #endif
341 error_1:
342 unregister_filesystem(&nfs_fs_type);
343 error_0:
344 return ret;
345 }
346
347 /*
348 * Unregister the NFS filesystems
349 */
unregister_nfs_fs(void)350 void __exit unregister_nfs_fs(void)
351 {
352 unregister_shrinker(&acl_shrinker);
353 #ifdef CONFIG_NFS_V4
354 unregister_filesystem(&nfs4_fs_type);
355 #endif
356 nfs_unregister_sysctl();
357 unregister_filesystem(&nfs_fs_type);
358 }
359
nfs_sb_active(struct super_block * sb)360 void nfs_sb_active(struct super_block *sb)
361 {
362 struct nfs_server *server = NFS_SB(sb);
363
364 if (atomic_inc_return(&server->active) == 1)
365 atomic_inc(&sb->s_active);
366 }
367
nfs_sb_deactive(struct super_block * sb)368 void nfs_sb_deactive(struct super_block *sb)
369 {
370 struct nfs_server *server = NFS_SB(sb);
371
372 if (atomic_dec_and_test(&server->active))
373 deactivate_super(sb);
374 }
375
376 /*
377 * Deliver file system statistics to userspace
378 */
nfs_statfs(struct dentry * dentry,struct kstatfs * buf)379 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
380 {
381 struct nfs_server *server = NFS_SB(dentry->d_sb);
382 unsigned char blockbits;
383 unsigned long blockres;
384 struct nfs_fh *fh = NFS_FH(dentry->d_inode);
385 struct nfs_fattr fattr;
386 struct nfs_fsstat res = {
387 .fattr = &fattr,
388 };
389 int error;
390
391 error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
392 if (error < 0)
393 goto out_err;
394 buf->f_type = NFS_SUPER_MAGIC;
395
396 /*
397 * Current versions of glibc do not correctly handle the
398 * case where f_frsize != f_bsize. Eventually we want to
399 * report the value of wtmult in this field.
400 */
401 buf->f_frsize = dentry->d_sb->s_blocksize;
402
403 /*
404 * On most *nix systems, f_blocks, f_bfree, and f_bavail
405 * are reported in units of f_frsize. Linux hasn't had
406 * an f_frsize field in its statfs struct until recently,
407 * thus historically Linux's sys_statfs reports these
408 * fields in units of f_bsize.
409 */
410 buf->f_bsize = dentry->d_sb->s_blocksize;
411 blockbits = dentry->d_sb->s_blocksize_bits;
412 blockres = (1 << blockbits) - 1;
413 buf->f_blocks = (res.tbytes + blockres) >> blockbits;
414 buf->f_bfree = (res.fbytes + blockres) >> blockbits;
415 buf->f_bavail = (res.abytes + blockres) >> blockbits;
416
417 buf->f_files = res.tfiles;
418 buf->f_ffree = res.afiles;
419
420 buf->f_namelen = server->namelen;
421
422 return 0;
423
424 out_err:
425 dprintk("%s: statfs error = %d\n", __func__, -error);
426 return error;
427 }
428
429 /*
430 * Map the security flavour number to a name
431 */
nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)432 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
433 {
434 static const struct {
435 rpc_authflavor_t flavour;
436 const char *str;
437 } sec_flavours[] = {
438 { RPC_AUTH_NULL, "null" },
439 { RPC_AUTH_UNIX, "sys" },
440 { RPC_AUTH_GSS_KRB5, "krb5" },
441 { RPC_AUTH_GSS_KRB5I, "krb5i" },
442 { RPC_AUTH_GSS_KRB5P, "krb5p" },
443 { RPC_AUTH_GSS_LKEY, "lkey" },
444 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
445 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
446 { RPC_AUTH_GSS_SPKM, "spkm" },
447 { RPC_AUTH_GSS_SPKMI, "spkmi" },
448 { RPC_AUTH_GSS_SPKMP, "spkmp" },
449 { UINT_MAX, "unknown" }
450 };
451 int i;
452
453 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
454 if (sec_flavours[i].flavour == flavour)
455 break;
456 }
457 return sec_flavours[i].str;
458 }
459
nfs_show_mountd_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)460 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
461 int showdefaults)
462 {
463 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
464
465 switch (sap->sa_family) {
466 case AF_INET: {
467 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
468 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
469 break;
470 }
471 case AF_INET6: {
472 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
473 seq_printf(m, ",mountaddr=%pI6", &sin6->sin6_addr);
474 break;
475 }
476 default:
477 if (showdefaults)
478 seq_printf(m, ",mountaddr=unspecified");
479 }
480
481 if (nfss->mountd_version || showdefaults)
482 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
483 if (nfss->mountd_port || showdefaults)
484 seq_printf(m, ",mountport=%u", nfss->mountd_port);
485
486 switch (nfss->mountd_protocol) {
487 case IPPROTO_UDP:
488 seq_printf(m, ",mountproto=udp");
489 break;
490 case IPPROTO_TCP:
491 seq_printf(m, ",mountproto=tcp");
492 break;
493 default:
494 if (showdefaults)
495 seq_printf(m, ",mountproto=auto");
496 }
497 }
498
499 /*
500 * Describe the mount options in force on this server representation
501 */
nfs_show_mount_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)502 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
503 int showdefaults)
504 {
505 static const struct proc_nfs_info {
506 int flag;
507 const char *str;
508 const char *nostr;
509 } nfs_info[] = {
510 { NFS_MOUNT_SOFT, ",soft", ",hard" },
511 { NFS_MOUNT_INTR, ",intr", ",nointr" },
512 { NFS_MOUNT_POSIX, ",posix", "" },
513 { NFS_MOUNT_NOCTO, ",nocto", "" },
514 { NFS_MOUNT_NOAC, ",noac", "" },
515 { NFS_MOUNT_NONLM, ",nolock", "" },
516 { NFS_MOUNT_NOACL, ",noacl", "" },
517 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
518 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
519 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
520 { 0, NULL, NULL }
521 };
522 const struct proc_nfs_info *nfs_infop;
523 struct nfs_client *clp = nfss->nfs_client;
524 u32 version = clp->rpc_ops->version;
525
526 seq_printf(m, ",vers=%u", version);
527 seq_printf(m, ",rsize=%u", nfss->rsize);
528 seq_printf(m, ",wsize=%u", nfss->wsize);
529 if (nfss->bsize != 0)
530 seq_printf(m, ",bsize=%u", nfss->bsize);
531 seq_printf(m, ",namlen=%u", nfss->namelen);
532 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
533 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
534 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
535 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
536 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
537 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
538 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
539 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
540 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
541 if (nfss->flags & nfs_infop->flag)
542 seq_puts(m, nfs_infop->str);
543 else
544 seq_puts(m, nfs_infop->nostr);
545 }
546 seq_printf(m, ",proto=%s",
547 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
548 if (version == 4) {
549 if (nfss->port != NFS_PORT)
550 seq_printf(m, ",port=%u", nfss->port);
551 } else
552 if (nfss->port)
553 seq_printf(m, ",port=%u", nfss->port);
554
555 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
556 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
557 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
558
559 if (version != 4)
560 nfs_show_mountd_options(m, nfss, showdefaults);
561
562 #ifdef CONFIG_NFS_V4
563 if (clp->rpc_ops->version == 4)
564 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
565 #endif
566 }
567
568 /*
569 * Describe the mount options on this VFS mountpoint
570 */
nfs_show_options(struct seq_file * m,struct vfsmount * mnt)571 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
572 {
573 struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
574
575 nfs_show_mount_options(m, nfss, 0);
576
577 seq_printf(m, ",addr=%s",
578 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
579 RPC_DISPLAY_ADDR));
580
581 return 0;
582 }
583
584 /*
585 * Present statistical information for this VFS mountpoint
586 */
nfs_show_stats(struct seq_file * m,struct vfsmount * mnt)587 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
588 {
589 int i, cpu;
590 struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
591 struct rpc_auth *auth = nfss->client->cl_auth;
592 struct nfs_iostats totals = { };
593
594 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
595
596 /*
597 * Display all mount option settings
598 */
599 seq_printf(m, "\n\topts:\t");
600 seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
601 seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
602 seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
603 seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
604 nfs_show_mount_options(m, nfss, 1);
605
606 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
607
608 seq_printf(m, "\n\tcaps:\t");
609 seq_printf(m, "caps=0x%x", nfss->caps);
610 seq_printf(m, ",wtmult=%u", nfss->wtmult);
611 seq_printf(m, ",dtsize=%u", nfss->dtsize);
612 seq_printf(m, ",bsize=%u", nfss->bsize);
613 seq_printf(m, ",namlen=%u", nfss->namelen);
614
615 #ifdef CONFIG_NFS_V4
616 if (nfss->nfs_client->rpc_ops->version == 4) {
617 seq_printf(m, "\n\tnfsv4:\t");
618 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
619 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
620 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
621 }
622 #endif
623
624 /*
625 * Display security flavor in effect for this mount
626 */
627 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
628 if (auth->au_flavor)
629 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
630
631 /*
632 * Display superblock I/O counters
633 */
634 for_each_possible_cpu(cpu) {
635 struct nfs_iostats *stats;
636
637 preempt_disable();
638 stats = per_cpu_ptr(nfss->io_stats, cpu);
639
640 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
641 totals.events[i] += stats->events[i];
642 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
643 totals.bytes[i] += stats->bytes[i];
644
645 preempt_enable();
646 }
647
648 seq_printf(m, "\n\tevents:\t");
649 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
650 seq_printf(m, "%lu ", totals.events[i]);
651 seq_printf(m, "\n\tbytes:\t");
652 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
653 seq_printf(m, "%Lu ", totals.bytes[i]);
654 seq_printf(m, "\n");
655
656 rpc_print_iostats(m, nfss->client);
657
658 return 0;
659 }
660
661 /*
662 * Begin unmount by attempting to remove all automounted mountpoints we added
663 * in response to xdev traversals and referrals
664 */
nfs_umount_begin(struct super_block * sb)665 static void nfs_umount_begin(struct super_block *sb)
666 {
667 struct nfs_server *server = NFS_SB(sb);
668 struct rpc_clnt *rpc;
669
670 /* -EIO all pending I/O */
671 rpc = server->client_acl;
672 if (!IS_ERR(rpc))
673 rpc_killall_tasks(rpc);
674 rpc = server->client;
675 if (!IS_ERR(rpc))
676 rpc_killall_tasks(rpc);
677 }
678
679 /*
680 * Sanity-check a server address provided by the mount command.
681 *
682 * Address family must be initialized, and address must not be
683 * the ANY address for that family.
684 */
nfs_verify_server_address(struct sockaddr * addr)685 static int nfs_verify_server_address(struct sockaddr *addr)
686 {
687 switch (addr->sa_family) {
688 case AF_INET: {
689 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
690 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
691 }
692 case AF_INET6: {
693 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
694 return !ipv6_addr_any(sa);
695 }
696 }
697
698 return 0;
699 }
700
nfs_parse_ipv4_address(char * string,size_t str_len,struct sockaddr * sap,size_t * addr_len)701 static void nfs_parse_ipv4_address(char *string, size_t str_len,
702 struct sockaddr *sap, size_t *addr_len)
703 {
704 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
705 u8 *addr = (u8 *)&sin->sin_addr.s_addr;
706
707 if (str_len <= INET_ADDRSTRLEN) {
708 dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
709 (int)str_len, string);
710
711 sin->sin_family = AF_INET;
712 *addr_len = sizeof(*sin);
713 if (in4_pton(string, str_len, addr, '\0', NULL))
714 return;
715 }
716
717 sap->sa_family = AF_UNSPEC;
718 *addr_len = 0;
719 }
720
721 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
nfs_parse_ipv6_scope_id(const char * string,const size_t str_len,const char * delim,struct sockaddr_in6 * sin6)722 static int nfs_parse_ipv6_scope_id(const char *string, const size_t str_len,
723 const char *delim,
724 struct sockaddr_in6 *sin6)
725 {
726 char *p;
727 size_t len;
728
729 if ((string + str_len) == delim)
730 return 1;
731
732 if (*delim != IPV6_SCOPE_DELIMITER)
733 return 0;
734
735 if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
736 return 0;
737
738 len = (string + str_len) - delim - 1;
739 p = kstrndup(delim + 1, len, GFP_KERNEL);
740 if (p) {
741 unsigned long scope_id = 0;
742 struct net_device *dev;
743
744 dev = dev_get_by_name(&init_net, p);
745 if (dev != NULL) {
746 scope_id = dev->ifindex;
747 dev_put(dev);
748 } else {
749 if (strict_strtoul(p, 10, &scope_id) == 0) {
750 kfree(p);
751 return 0;
752 }
753 }
754
755 kfree(p);
756
757 sin6->sin6_scope_id = scope_id;
758 dfprintk(MOUNT, "NFS: IPv6 scope ID = %lu\n", scope_id);
759 return 1;
760 }
761
762 return 0;
763 }
764
nfs_parse_ipv6_address(char * string,size_t str_len,struct sockaddr * sap,size_t * addr_len)765 static void nfs_parse_ipv6_address(char *string, size_t str_len,
766 struct sockaddr *sap, size_t *addr_len)
767 {
768 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
769 u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
770 const char *delim;
771
772 if (str_len <= INET6_ADDRSTRLEN) {
773 dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
774 (int)str_len, string);
775
776 sin6->sin6_family = AF_INET6;
777 *addr_len = sizeof(*sin6);
778 if (in6_pton(string, str_len, addr,
779 IPV6_SCOPE_DELIMITER, &delim) != 0) {
780 if (nfs_parse_ipv6_scope_id(string, str_len,
781 delim, sin6) != 0)
782 return;
783 }
784 }
785
786 sap->sa_family = AF_UNSPEC;
787 *addr_len = 0;
788 }
789 #else
nfs_parse_ipv6_address(char * string,size_t str_len,struct sockaddr * sap,size_t * addr_len)790 static void nfs_parse_ipv6_address(char *string, size_t str_len,
791 struct sockaddr *sap, size_t *addr_len)
792 {
793 sap->sa_family = AF_UNSPEC;
794 *addr_len = 0;
795 }
796 #endif
797
798 /*
799 * Construct a sockaddr based on the contents of a string that contains
800 * an IP address in presentation format.
801 *
802 * If there is a problem constructing the new sockaddr, set the address
803 * family to AF_UNSPEC.
804 */
nfs_parse_ip_address(char * string,size_t str_len,struct sockaddr * sap,size_t * addr_len)805 void nfs_parse_ip_address(char *string, size_t str_len,
806 struct sockaddr *sap, size_t *addr_len)
807 {
808 unsigned int i, colons;
809
810 colons = 0;
811 for (i = 0; i < str_len; i++)
812 if (string[i] == ':')
813 colons++;
814
815 if (colons >= 2)
816 nfs_parse_ipv6_address(string, str_len, sap, addr_len);
817 else
818 nfs_parse_ipv4_address(string, str_len, sap, addr_len);
819 }
820
821 /*
822 * Sanity check the NFS transport protocol.
823 *
824 */
nfs_validate_transport_protocol(struct nfs_parsed_mount_data * mnt)825 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
826 {
827 switch (mnt->nfs_server.protocol) {
828 case XPRT_TRANSPORT_UDP:
829 case XPRT_TRANSPORT_TCP:
830 case XPRT_TRANSPORT_RDMA:
831 break;
832 default:
833 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
834 }
835 }
836
837 /*
838 * For text based NFSv2/v3 mounts, the mount protocol transport default
839 * settings should depend upon the specified NFS transport.
840 */
nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data * mnt)841 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
842 {
843 nfs_validate_transport_protocol(mnt);
844
845 if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
846 mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
847 return;
848 switch (mnt->nfs_server.protocol) {
849 case XPRT_TRANSPORT_UDP:
850 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
851 break;
852 case XPRT_TRANSPORT_TCP:
853 case XPRT_TRANSPORT_RDMA:
854 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
855 }
856 }
857
858 /*
859 * Parse the value of the 'sec=' option.
860 *
861 * The flavor_len setting is for v4 mounts.
862 */
nfs_parse_security_flavors(char * value,struct nfs_parsed_mount_data * mnt)863 static int nfs_parse_security_flavors(char *value,
864 struct nfs_parsed_mount_data *mnt)
865 {
866 substring_t args[MAX_OPT_ARGS];
867
868 dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
869
870 switch (match_token(value, nfs_secflavor_tokens, args)) {
871 case Opt_sec_none:
872 mnt->auth_flavor_len = 0;
873 mnt->auth_flavors[0] = RPC_AUTH_NULL;
874 break;
875 case Opt_sec_sys:
876 mnt->auth_flavor_len = 0;
877 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
878 break;
879 case Opt_sec_krb5:
880 mnt->auth_flavor_len = 1;
881 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
882 break;
883 case Opt_sec_krb5i:
884 mnt->auth_flavor_len = 1;
885 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
886 break;
887 case Opt_sec_krb5p:
888 mnt->auth_flavor_len = 1;
889 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
890 break;
891 case Opt_sec_lkey:
892 mnt->auth_flavor_len = 1;
893 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
894 break;
895 case Opt_sec_lkeyi:
896 mnt->auth_flavor_len = 1;
897 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
898 break;
899 case Opt_sec_lkeyp:
900 mnt->auth_flavor_len = 1;
901 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
902 break;
903 case Opt_sec_spkm:
904 mnt->auth_flavor_len = 1;
905 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
906 break;
907 case Opt_sec_spkmi:
908 mnt->auth_flavor_len = 1;
909 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
910 break;
911 case Opt_sec_spkmp:
912 mnt->auth_flavor_len = 1;
913 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
914 break;
915 default:
916 return 0;
917 }
918
919 return 1;
920 }
921
nfs_parse_invalid_value(const char * option)922 static void nfs_parse_invalid_value(const char *option)
923 {
924 dfprintk(MOUNT, "NFS: bad value specified for %s option\n", option);
925 }
926
927 /*
928 * Error-check and convert a string of mount options from user space into
929 * a data structure. The whole mount string is processed; bad options are
930 * skipped as they are encountered. If there were no errors, return 1;
931 * otherwise return 0 (zero).
932 */
nfs_parse_mount_options(char * raw,struct nfs_parsed_mount_data * mnt)933 static int nfs_parse_mount_options(char *raw,
934 struct nfs_parsed_mount_data *mnt)
935 {
936 char *p, *string, *secdata;
937 int rc, sloppy = 0, errors = 0;
938
939 if (!raw) {
940 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
941 return 1;
942 }
943 dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
944
945 secdata = alloc_secdata();
946 if (!secdata)
947 goto out_nomem;
948
949 rc = security_sb_copy_data(raw, secdata);
950 if (rc)
951 goto out_security_failure;
952
953 rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
954 if (rc)
955 goto out_security_failure;
956
957 free_secdata(secdata);
958
959 while ((p = strsep(&raw, ",")) != NULL) {
960 substring_t args[MAX_OPT_ARGS];
961 int option, token;
962
963 if (!*p)
964 continue;
965
966 dfprintk(MOUNT, "NFS: parsing nfs mount option '%s'\n", p);
967
968 token = match_token(p, nfs_mount_option_tokens, args);
969 switch (token) {
970
971 /*
972 * boolean options: foo/nofoo
973 */
974 case Opt_soft:
975 mnt->flags |= NFS_MOUNT_SOFT;
976 break;
977 case Opt_hard:
978 mnt->flags &= ~NFS_MOUNT_SOFT;
979 break;
980 case Opt_posix:
981 mnt->flags |= NFS_MOUNT_POSIX;
982 break;
983 case Opt_noposix:
984 mnt->flags &= ~NFS_MOUNT_POSIX;
985 break;
986 case Opt_cto:
987 mnt->flags &= ~NFS_MOUNT_NOCTO;
988 break;
989 case Opt_nocto:
990 mnt->flags |= NFS_MOUNT_NOCTO;
991 break;
992 case Opt_ac:
993 mnt->flags &= ~NFS_MOUNT_NOAC;
994 break;
995 case Opt_noac:
996 mnt->flags |= NFS_MOUNT_NOAC;
997 break;
998 case Opt_lock:
999 mnt->flags &= ~NFS_MOUNT_NONLM;
1000 break;
1001 case Opt_nolock:
1002 mnt->flags |= NFS_MOUNT_NONLM;
1003 break;
1004 case Opt_v2:
1005 mnt->flags &= ~NFS_MOUNT_VER3;
1006 break;
1007 case Opt_v3:
1008 mnt->flags |= NFS_MOUNT_VER3;
1009 break;
1010 case Opt_udp:
1011 mnt->flags &= ~NFS_MOUNT_TCP;
1012 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1013 break;
1014 case Opt_tcp:
1015 mnt->flags |= NFS_MOUNT_TCP;
1016 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1017 break;
1018 case Opt_rdma:
1019 mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1020 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1021 break;
1022 case Opt_acl:
1023 mnt->flags &= ~NFS_MOUNT_NOACL;
1024 break;
1025 case Opt_noacl:
1026 mnt->flags |= NFS_MOUNT_NOACL;
1027 break;
1028 case Opt_rdirplus:
1029 mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1030 break;
1031 case Opt_nordirplus:
1032 mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1033 break;
1034 case Opt_sharecache:
1035 mnt->flags &= ~NFS_MOUNT_UNSHARED;
1036 break;
1037 case Opt_nosharecache:
1038 mnt->flags |= NFS_MOUNT_UNSHARED;
1039 break;
1040 case Opt_resvport:
1041 mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1042 break;
1043 case Opt_noresvport:
1044 mnt->flags |= NFS_MOUNT_NORESVPORT;
1045 break;
1046
1047 /*
1048 * options that take numeric values
1049 */
1050 case Opt_port:
1051 if (match_int(args, &option) ||
1052 option < 0 || option > USHORT_MAX) {
1053 errors++;
1054 nfs_parse_invalid_value("port");
1055 } else
1056 mnt->nfs_server.port = option;
1057 break;
1058 case Opt_rsize:
1059 if (match_int(args, &option) || option < 0) {
1060 errors++;
1061 nfs_parse_invalid_value("rsize");
1062 } else
1063 mnt->rsize = option;
1064 break;
1065 case Opt_wsize:
1066 if (match_int(args, &option) || option < 0) {
1067 errors++;
1068 nfs_parse_invalid_value("wsize");
1069 } else
1070 mnt->wsize = option;
1071 break;
1072 case Opt_bsize:
1073 if (match_int(args, &option) || option < 0) {
1074 errors++;
1075 nfs_parse_invalid_value("bsize");
1076 } else
1077 mnt->bsize = option;
1078 break;
1079 case Opt_timeo:
1080 if (match_int(args, &option) || option <= 0) {
1081 errors++;
1082 nfs_parse_invalid_value("timeo");
1083 } else
1084 mnt->timeo = option;
1085 break;
1086 case Opt_retrans:
1087 if (match_int(args, &option) || option <= 0) {
1088 errors++;
1089 nfs_parse_invalid_value("retrans");
1090 } else
1091 mnt->retrans = option;
1092 break;
1093 case Opt_acregmin:
1094 if (match_int(args, &option) || option < 0) {
1095 errors++;
1096 nfs_parse_invalid_value("acregmin");
1097 } else
1098 mnt->acregmin = option;
1099 break;
1100 case Opt_acregmax:
1101 if (match_int(args, &option) || option < 0) {
1102 errors++;
1103 nfs_parse_invalid_value("acregmax");
1104 } else
1105 mnt->acregmax = option;
1106 break;
1107 case Opt_acdirmin:
1108 if (match_int(args, &option) || option < 0) {
1109 errors++;
1110 nfs_parse_invalid_value("acdirmin");
1111 } else
1112 mnt->acdirmin = option;
1113 break;
1114 case Opt_acdirmax:
1115 if (match_int(args, &option) || option < 0) {
1116 errors++;
1117 nfs_parse_invalid_value("acdirmax");
1118 } else
1119 mnt->acdirmax = option;
1120 break;
1121 case Opt_actimeo:
1122 if (match_int(args, &option) || option < 0) {
1123 errors++;
1124 nfs_parse_invalid_value("actimeo");
1125 } else
1126 mnt->acregmin = mnt->acregmax =
1127 mnt->acdirmin = mnt->acdirmax = option;
1128 break;
1129 case Opt_namelen:
1130 if (match_int(args, &option) || option < 0) {
1131 errors++;
1132 nfs_parse_invalid_value("namlen");
1133 } else
1134 mnt->namlen = option;
1135 break;
1136 case Opt_mountport:
1137 if (match_int(args, &option) ||
1138 option < 0 || option > USHORT_MAX) {
1139 errors++;
1140 nfs_parse_invalid_value("mountport");
1141 } else
1142 mnt->mount_server.port = option;
1143 break;
1144 case Opt_mountvers:
1145 if (match_int(args, &option) ||
1146 option < NFS_MNT_VERSION ||
1147 option > NFS_MNT3_VERSION) {
1148 errors++;
1149 nfs_parse_invalid_value("mountvers");
1150 } else
1151 mnt->mount_server.version = option;
1152 break;
1153 case Opt_nfsvers:
1154 if (match_int(args, &option)) {
1155 errors++;
1156 nfs_parse_invalid_value("nfsvers");
1157 break;
1158 }
1159 switch (option) {
1160 case NFS2_VERSION:
1161 mnt->flags &= ~NFS_MOUNT_VER3;
1162 break;
1163 case NFS3_VERSION:
1164 mnt->flags |= NFS_MOUNT_VER3;
1165 break;
1166 default:
1167 errors++;
1168 nfs_parse_invalid_value("nfsvers");
1169 }
1170 break;
1171
1172 /*
1173 * options that take text values
1174 */
1175 case Opt_sec:
1176 string = match_strdup(args);
1177 if (string == NULL)
1178 goto out_nomem;
1179 rc = nfs_parse_security_flavors(string, mnt);
1180 kfree(string);
1181 if (!rc) {
1182 errors++;
1183 dfprintk(MOUNT, "NFS: unrecognized "
1184 "security flavor\n");
1185 }
1186 break;
1187 case Opt_proto:
1188 string = match_strdup(args);
1189 if (string == NULL)
1190 goto out_nomem;
1191 token = match_token(string,
1192 nfs_xprt_protocol_tokens, args);
1193 kfree(string);
1194
1195 switch (token) {
1196 case Opt_xprt_udp:
1197 mnt->flags &= ~NFS_MOUNT_TCP;
1198 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1199 break;
1200 case Opt_xprt_tcp:
1201 mnt->flags |= NFS_MOUNT_TCP;
1202 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1203 break;
1204 case Opt_xprt_rdma:
1205 /* vector side protocols to TCP */
1206 mnt->flags |= NFS_MOUNT_TCP;
1207 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1208 break;
1209 default:
1210 errors++;
1211 dfprintk(MOUNT, "NFS: unrecognized "
1212 "transport protocol\n");
1213 }
1214 break;
1215 case Opt_mountproto:
1216 string = match_strdup(args);
1217 if (string == NULL)
1218 goto out_nomem;
1219 token = match_token(string,
1220 nfs_xprt_protocol_tokens, args);
1221 kfree(string);
1222
1223 switch (token) {
1224 case Opt_xprt_udp:
1225 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1226 break;
1227 case Opt_xprt_tcp:
1228 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1229 break;
1230 case Opt_xprt_rdma: /* not used for side protocols */
1231 default:
1232 errors++;
1233 dfprintk(MOUNT, "NFS: unrecognized "
1234 "transport protocol\n");
1235 }
1236 break;
1237 case Opt_addr:
1238 string = match_strdup(args);
1239 if (string == NULL)
1240 goto out_nomem;
1241 nfs_parse_ip_address(string, strlen(string),
1242 (struct sockaddr *)
1243 &mnt->nfs_server.address,
1244 &mnt->nfs_server.addrlen);
1245 kfree(string);
1246 break;
1247 case Opt_clientaddr:
1248 string = match_strdup(args);
1249 if (string == NULL)
1250 goto out_nomem;
1251 kfree(mnt->client_address);
1252 mnt->client_address = string;
1253 break;
1254 case Opt_mounthost:
1255 string = match_strdup(args);
1256 if (string == NULL)
1257 goto out_nomem;
1258 kfree(mnt->mount_server.hostname);
1259 mnt->mount_server.hostname = string;
1260 break;
1261 case Opt_mountaddr:
1262 string = match_strdup(args);
1263 if (string == NULL)
1264 goto out_nomem;
1265 nfs_parse_ip_address(string, strlen(string),
1266 (struct sockaddr *)
1267 &mnt->mount_server.address,
1268 &mnt->mount_server.addrlen);
1269 kfree(string);
1270 break;
1271 case Opt_lookupcache:
1272 string = match_strdup(args);
1273 if (string == NULL)
1274 goto out_nomem;
1275 token = match_token(string,
1276 nfs_lookupcache_tokens, args);
1277 kfree(string);
1278 switch (token) {
1279 case Opt_lookupcache_all:
1280 mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1281 break;
1282 case Opt_lookupcache_positive:
1283 mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1284 mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1285 break;
1286 case Opt_lookupcache_none:
1287 mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1288 break;
1289 default:
1290 errors++;
1291 dfprintk(MOUNT, "NFS: invalid "
1292 "lookupcache argument\n");
1293 };
1294 break;
1295
1296 /*
1297 * Special options
1298 */
1299 case Opt_sloppy:
1300 sloppy = 1;
1301 dfprintk(MOUNT, "NFS: relaxing parsing rules\n");
1302 break;
1303 case Opt_userspace:
1304 case Opt_deprecated:
1305 dfprintk(MOUNT, "NFS: ignoring mount option "
1306 "'%s'\n", p);
1307 break;
1308
1309 default:
1310 errors++;
1311 dfprintk(MOUNT, "NFS: unrecognized mount option "
1312 "'%s'\n", p);
1313 }
1314 }
1315
1316 if (errors > 0) {
1317 dfprintk(MOUNT, "NFS: parsing encountered %d error%s\n",
1318 errors, (errors == 1 ? "" : "s"));
1319 if (!sloppy)
1320 return 0;
1321 }
1322 return 1;
1323
1324 out_nomem:
1325 printk(KERN_INFO "NFS: not enough memory to parse option\n");
1326 return 0;
1327 out_security_failure:
1328 free_secdata(secdata);
1329 printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1330 return 0;
1331 }
1332
1333 /*
1334 * Use the remote server's MOUNT service to request the NFS file handle
1335 * corresponding to the provided path.
1336 */
nfs_try_mount(struct nfs_parsed_mount_data * args,struct nfs_fh * root_fh)1337 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1338 struct nfs_fh *root_fh)
1339 {
1340 struct nfs_mount_request request = {
1341 .sap = (struct sockaddr *)
1342 &args->mount_server.address,
1343 .dirpath = args->nfs_server.export_path,
1344 .protocol = args->mount_server.protocol,
1345 .fh = root_fh,
1346 .noresvport = args->flags & NFS_MOUNT_NORESVPORT,
1347 };
1348 int status;
1349
1350 if (args->mount_server.version == 0) {
1351 if (args->flags & NFS_MOUNT_VER3)
1352 args->mount_server.version = NFS_MNT3_VERSION;
1353 else
1354 args->mount_server.version = NFS_MNT_VERSION;
1355 }
1356 request.version = args->mount_server.version;
1357
1358 if (args->mount_server.hostname)
1359 request.hostname = args->mount_server.hostname;
1360 else
1361 request.hostname = args->nfs_server.hostname;
1362
1363 /*
1364 * Construct the mount server's address.
1365 */
1366 if (args->mount_server.address.ss_family == AF_UNSPEC) {
1367 memcpy(request.sap, &args->nfs_server.address,
1368 args->nfs_server.addrlen);
1369 args->mount_server.addrlen = args->nfs_server.addrlen;
1370 }
1371 request.salen = args->mount_server.addrlen;
1372
1373 /*
1374 * autobind will be used if mount_server.port == 0
1375 */
1376 nfs_set_port(request.sap, args->mount_server.port);
1377
1378 /*
1379 * Now ask the mount server to map our export path
1380 * to a file handle.
1381 */
1382 status = nfs_mount(&request);
1383 if (status == 0)
1384 return 0;
1385
1386 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1387 request.hostname, status);
1388 return status;
1389 }
1390
nfs_parse_simple_hostname(const char * dev_name,char ** hostname,size_t maxnamlen,char ** export_path,size_t maxpathlen)1391 static int nfs_parse_simple_hostname(const char *dev_name,
1392 char **hostname, size_t maxnamlen,
1393 char **export_path, size_t maxpathlen)
1394 {
1395 size_t len;
1396 char *colon, *comma;
1397
1398 colon = strchr(dev_name, ':');
1399 if (colon == NULL)
1400 goto out_bad_devname;
1401
1402 len = colon - dev_name;
1403 if (len > maxnamlen)
1404 goto out_hostname;
1405
1406 /* N.B. caller will free nfs_server.hostname in all cases */
1407 *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1408 if (!*hostname)
1409 goto out_nomem;
1410
1411 /* kill possible hostname list: not supported */
1412 comma = strchr(*hostname, ',');
1413 if (comma != NULL) {
1414 if (comma == *hostname)
1415 goto out_bad_devname;
1416 *comma = '\0';
1417 }
1418
1419 colon++;
1420 len = strlen(colon);
1421 if (len > maxpathlen)
1422 goto out_path;
1423 *export_path = kstrndup(colon, len, GFP_KERNEL);
1424 if (!*export_path)
1425 goto out_nomem;
1426
1427 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1428 return 0;
1429
1430 out_bad_devname:
1431 dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1432 return -EINVAL;
1433
1434 out_nomem:
1435 dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1436 return -ENOMEM;
1437
1438 out_hostname:
1439 dfprintk(MOUNT, "NFS: server hostname too long\n");
1440 return -ENAMETOOLONG;
1441
1442 out_path:
1443 dfprintk(MOUNT, "NFS: export pathname too long\n");
1444 return -ENAMETOOLONG;
1445 }
1446
1447 /*
1448 * Hostname has square brackets around it because it contains one or
1449 * more colons. We look for the first closing square bracket, and a
1450 * colon must follow it.
1451 */
nfs_parse_protected_hostname(const char * dev_name,char ** hostname,size_t maxnamlen,char ** export_path,size_t maxpathlen)1452 static int nfs_parse_protected_hostname(const char *dev_name,
1453 char **hostname, size_t maxnamlen,
1454 char **export_path, size_t maxpathlen)
1455 {
1456 size_t len;
1457 char *start, *end;
1458
1459 start = (char *)(dev_name + 1);
1460
1461 end = strchr(start, ']');
1462 if (end == NULL)
1463 goto out_bad_devname;
1464 if (*(end + 1) != ':')
1465 goto out_bad_devname;
1466
1467 len = end - start;
1468 if (len > maxnamlen)
1469 goto out_hostname;
1470
1471 /* N.B. caller will free nfs_server.hostname in all cases */
1472 *hostname = kstrndup(start, len, GFP_KERNEL);
1473 if (*hostname == NULL)
1474 goto out_nomem;
1475
1476 end += 2;
1477 len = strlen(end);
1478 if (len > maxpathlen)
1479 goto out_path;
1480 *export_path = kstrndup(end, len, GFP_KERNEL);
1481 if (!*export_path)
1482 goto out_nomem;
1483
1484 return 0;
1485
1486 out_bad_devname:
1487 dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1488 return -EINVAL;
1489
1490 out_nomem:
1491 dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1492 return -ENOMEM;
1493
1494 out_hostname:
1495 dfprintk(MOUNT, "NFS: server hostname too long\n");
1496 return -ENAMETOOLONG;
1497
1498 out_path:
1499 dfprintk(MOUNT, "NFS: export pathname too long\n");
1500 return -ENAMETOOLONG;
1501 }
1502
1503 /*
1504 * Split "dev_name" into "hostname:export_path".
1505 *
1506 * The leftmost colon demarks the split between the server's hostname
1507 * and the export path. If the hostname starts with a left square
1508 * bracket, then it may contain colons.
1509 *
1510 * Note: caller frees hostname and export path, even on error.
1511 */
nfs_parse_devname(const char * dev_name,char ** hostname,size_t maxnamlen,char ** export_path,size_t maxpathlen)1512 static int nfs_parse_devname(const char *dev_name,
1513 char **hostname, size_t maxnamlen,
1514 char **export_path, size_t maxpathlen)
1515 {
1516 if (*dev_name == '[')
1517 return nfs_parse_protected_hostname(dev_name,
1518 hostname, maxnamlen,
1519 export_path, maxpathlen);
1520
1521 return nfs_parse_simple_hostname(dev_name,
1522 hostname, maxnamlen,
1523 export_path, maxpathlen);
1524 }
1525
1526 /*
1527 * Validate the NFS2/NFS3 mount data
1528 * - fills in the mount root filehandle
1529 *
1530 * For option strings, user space handles the following behaviors:
1531 *
1532 * + DNS: mapping server host name to IP address ("addr=" option)
1533 *
1534 * + failure mode: how to behave if a mount request can't be handled
1535 * immediately ("fg/bg" option)
1536 *
1537 * + retry: how often to retry a mount request ("retry=" option)
1538 *
1539 * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1540 * mountproto=tcp after mountproto=udp, and so on
1541 */
nfs_validate_mount_data(void * options,struct nfs_parsed_mount_data * args,struct nfs_fh * mntfh,const char * dev_name)1542 static int nfs_validate_mount_data(void *options,
1543 struct nfs_parsed_mount_data *args,
1544 struct nfs_fh *mntfh,
1545 const char *dev_name)
1546 {
1547 struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1548
1549 if (data == NULL)
1550 goto out_no_data;
1551
1552 args->flags = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1553 args->rsize = NFS_MAX_FILE_IO_SIZE;
1554 args->wsize = NFS_MAX_FILE_IO_SIZE;
1555 args->acregmin = NFS_DEF_ACREGMIN;
1556 args->acregmax = NFS_DEF_ACREGMAX;
1557 args->acdirmin = NFS_DEF_ACDIRMIN;
1558 args->acdirmax = NFS_DEF_ACDIRMAX;
1559 args->mount_server.port = 0; /* autobind unless user sets port */
1560 args->nfs_server.port = 0; /* autobind unless user sets port */
1561 args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1562 args->auth_flavors[0] = RPC_AUTH_UNIX;
1563
1564 switch (data->version) {
1565 case 1:
1566 data->namlen = 0;
1567 case 2:
1568 data->bsize = 0;
1569 case 3:
1570 if (data->flags & NFS_MOUNT_VER3)
1571 goto out_no_v3;
1572 data->root.size = NFS2_FHSIZE;
1573 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1574 case 4:
1575 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1576 goto out_no_sec;
1577 case 5:
1578 memset(data->context, 0, sizeof(data->context));
1579 case 6:
1580 if (data->flags & NFS_MOUNT_VER3) {
1581 if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1582 goto out_invalid_fh;
1583 mntfh->size = data->root.size;
1584 } else
1585 mntfh->size = NFS2_FHSIZE;
1586
1587
1588 memcpy(mntfh->data, data->root.data, mntfh->size);
1589 if (mntfh->size < sizeof(mntfh->data))
1590 memset(mntfh->data + mntfh->size, 0,
1591 sizeof(mntfh->data) - mntfh->size);
1592
1593 /*
1594 * Translate to nfs_parsed_mount_data, which nfs_fill_super
1595 * can deal with.
1596 */
1597 args->flags = data->flags & NFS_MOUNT_FLAGMASK;
1598 args->rsize = data->rsize;
1599 args->wsize = data->wsize;
1600 args->timeo = data->timeo;
1601 args->retrans = data->retrans;
1602 args->acregmin = data->acregmin;
1603 args->acregmax = data->acregmax;
1604 args->acdirmin = data->acdirmin;
1605 args->acdirmax = data->acdirmax;
1606
1607 memcpy(&args->nfs_server.address, &data->addr,
1608 sizeof(data->addr));
1609 args->nfs_server.addrlen = sizeof(data->addr);
1610 if (!nfs_verify_server_address((struct sockaddr *)
1611 &args->nfs_server.address))
1612 goto out_no_address;
1613
1614 if (!(data->flags & NFS_MOUNT_TCP))
1615 args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1616 /* N.B. caller will free nfs_server.hostname in all cases */
1617 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1618 args->namlen = data->namlen;
1619 args->bsize = data->bsize;
1620
1621 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1622 args->auth_flavors[0] = data->pseudoflavor;
1623 if (!args->nfs_server.hostname)
1624 goto out_nomem;
1625
1626 /*
1627 * The legacy version 6 binary mount data from userspace has a
1628 * field used only to transport selinux information into the
1629 * the kernel. To continue to support that functionality we
1630 * have a touch of selinux knowledge here in the NFS code. The
1631 * userspace code converted context=blah to just blah so we are
1632 * converting back to the full string selinux understands.
1633 */
1634 if (data->context[0]){
1635 #ifdef CONFIG_SECURITY_SELINUX
1636 int rc;
1637 char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1638 if (!opts_str)
1639 return -ENOMEM;
1640 strcpy(opts_str, "context=");
1641 data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1642 strcat(opts_str, &data->context[0]);
1643 rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1644 kfree(opts_str);
1645 if (rc)
1646 return rc;
1647 #else
1648 return -EINVAL;
1649 #endif
1650 }
1651
1652 break;
1653 default: {
1654 int status;
1655
1656 if (nfs_parse_mount_options((char *)options, args) == 0)
1657 return -EINVAL;
1658
1659 if (!nfs_verify_server_address((struct sockaddr *)
1660 &args->nfs_server.address))
1661 goto out_no_address;
1662
1663 nfs_set_port((struct sockaddr *)&args->nfs_server.address,
1664 args->nfs_server.port);
1665
1666 nfs_set_mount_transport_protocol(args);
1667
1668 status = nfs_parse_devname(dev_name,
1669 &args->nfs_server.hostname,
1670 PAGE_SIZE,
1671 &args->nfs_server.export_path,
1672 NFS_MAXPATHLEN);
1673 if (!status)
1674 status = nfs_try_mount(args, mntfh);
1675
1676 kfree(args->nfs_server.export_path);
1677 args->nfs_server.export_path = NULL;
1678
1679 if (status)
1680 return status;
1681
1682 break;
1683 }
1684 }
1685
1686 #ifndef CONFIG_NFS_V3
1687 if (args->flags & NFS_MOUNT_VER3)
1688 goto out_v3_not_compiled;
1689 #endif /* !CONFIG_NFS_V3 */
1690
1691 return 0;
1692
1693 out_no_data:
1694 dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1695 return -EINVAL;
1696
1697 out_no_v3:
1698 dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1699 data->version);
1700 return -EINVAL;
1701
1702 out_no_sec:
1703 dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1704 return -EINVAL;
1705
1706 #ifndef CONFIG_NFS_V3
1707 out_v3_not_compiled:
1708 dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1709 return -EPROTONOSUPPORT;
1710 #endif /* !CONFIG_NFS_V3 */
1711
1712 out_nomem:
1713 dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1714 return -ENOMEM;
1715
1716 out_no_address:
1717 dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1718 return -EINVAL;
1719
1720 out_invalid_fh:
1721 dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1722 return -EINVAL;
1723 }
1724
1725 static int
nfs_compare_remount_data(struct nfs_server * nfss,struct nfs_parsed_mount_data * data)1726 nfs_compare_remount_data(struct nfs_server *nfss,
1727 struct nfs_parsed_mount_data *data)
1728 {
1729 if (data->flags != nfss->flags ||
1730 data->rsize != nfss->rsize ||
1731 data->wsize != nfss->wsize ||
1732 data->retrans != nfss->client->cl_timeout->to_retries ||
1733 data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1734 data->acregmin != nfss->acregmin / HZ ||
1735 data->acregmax != nfss->acregmax / HZ ||
1736 data->acdirmin != nfss->acdirmin / HZ ||
1737 data->acdirmax != nfss->acdirmax / HZ ||
1738 data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1739 data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1740 memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1741 data->nfs_server.addrlen) != 0)
1742 return -EINVAL;
1743
1744 return 0;
1745 }
1746
1747 static int
nfs_remount(struct super_block * sb,int * flags,char * raw_data)1748 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1749 {
1750 int error;
1751 struct nfs_server *nfss = sb->s_fs_info;
1752 struct nfs_parsed_mount_data *data;
1753 struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1754 struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1755 u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1756
1757 /*
1758 * Userspace mount programs that send binary options generally send
1759 * them populated with default values. We have no way to know which
1760 * ones were explicitly specified. Fall back to legacy behavior and
1761 * just return success.
1762 */
1763 if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1764 (nfsvers <= 3 && (!options || (options->version >= 1 &&
1765 options->version <= 6))))
1766 return 0;
1767
1768 data = kzalloc(sizeof(*data), GFP_KERNEL);
1769 if (data == NULL)
1770 return -ENOMEM;
1771
1772 /* fill out struct with values from existing mount */
1773 data->flags = nfss->flags;
1774 data->rsize = nfss->rsize;
1775 data->wsize = nfss->wsize;
1776 data->retrans = nfss->client->cl_timeout->to_retries;
1777 data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1778 data->acregmin = nfss->acregmin / HZ;
1779 data->acregmax = nfss->acregmax / HZ;
1780 data->acdirmin = nfss->acdirmin / HZ;
1781 data->acdirmax = nfss->acdirmax / HZ;
1782 data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1783 data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1784 memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1785 data->nfs_server.addrlen);
1786
1787 /* overwrite those values with any that were specified */
1788 error = nfs_parse_mount_options((char *)options, data);
1789 if (error < 0)
1790 goto out;
1791
1792 /* compare new mount options with old ones */
1793 error = nfs_compare_remount_data(nfss, data);
1794 out:
1795 kfree(data);
1796 return error;
1797 }
1798
1799 /*
1800 * Initialise the common bits of the superblock
1801 */
nfs_initialise_sb(struct super_block * sb)1802 static inline void nfs_initialise_sb(struct super_block *sb)
1803 {
1804 struct nfs_server *server = NFS_SB(sb);
1805
1806 sb->s_magic = NFS_SUPER_MAGIC;
1807
1808 /* We probably want something more informative here */
1809 snprintf(sb->s_id, sizeof(sb->s_id),
1810 "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1811
1812 if (sb->s_blocksize == 0)
1813 sb->s_blocksize = nfs_block_bits(server->wsize,
1814 &sb->s_blocksize_bits);
1815
1816 if (server->flags & NFS_MOUNT_NOAC)
1817 sb->s_flags |= MS_SYNCHRONOUS;
1818
1819 nfs_super_set_maxbytes(sb, server->maxfilesize);
1820 }
1821
1822 /*
1823 * Finish setting up an NFS2/3 superblock
1824 */
nfs_fill_super(struct super_block * sb,struct nfs_parsed_mount_data * data)1825 static void nfs_fill_super(struct super_block *sb,
1826 struct nfs_parsed_mount_data *data)
1827 {
1828 struct nfs_server *server = NFS_SB(sb);
1829
1830 sb->s_blocksize_bits = 0;
1831 sb->s_blocksize = 0;
1832 if (data->bsize)
1833 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1834
1835 if (server->flags & NFS_MOUNT_VER3) {
1836 /* The VFS shouldn't apply the umask to mode bits. We will do
1837 * so ourselves when necessary.
1838 */
1839 sb->s_flags |= MS_POSIXACL;
1840 sb->s_time_gran = 1;
1841 }
1842
1843 sb->s_op = &nfs_sops;
1844 nfs_initialise_sb(sb);
1845 }
1846
1847 /*
1848 * Finish setting up a cloned NFS2/3 superblock
1849 */
nfs_clone_super(struct super_block * sb,const struct super_block * old_sb)1850 static void nfs_clone_super(struct super_block *sb,
1851 const struct super_block *old_sb)
1852 {
1853 struct nfs_server *server = NFS_SB(sb);
1854
1855 sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1856 sb->s_blocksize = old_sb->s_blocksize;
1857 sb->s_maxbytes = old_sb->s_maxbytes;
1858
1859 if (server->flags & NFS_MOUNT_VER3) {
1860 /* The VFS shouldn't apply the umask to mode bits. We will do
1861 * so ourselves when necessary.
1862 */
1863 sb->s_flags |= MS_POSIXACL;
1864 sb->s_time_gran = 1;
1865 }
1866
1867 sb->s_op = old_sb->s_op;
1868 nfs_initialise_sb(sb);
1869 }
1870
1871 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1872
nfs_compare_mount_options(const struct super_block * s,const struct nfs_server * b,int flags)1873 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1874 {
1875 const struct nfs_server *a = s->s_fs_info;
1876 const struct rpc_clnt *clnt_a = a->client;
1877 const struct rpc_clnt *clnt_b = b->client;
1878
1879 if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1880 goto Ebusy;
1881 if (a->nfs_client != b->nfs_client)
1882 goto Ebusy;
1883 if (a->flags != b->flags)
1884 goto Ebusy;
1885 if (a->wsize != b->wsize)
1886 goto Ebusy;
1887 if (a->rsize != b->rsize)
1888 goto Ebusy;
1889 if (a->acregmin != b->acregmin)
1890 goto Ebusy;
1891 if (a->acregmax != b->acregmax)
1892 goto Ebusy;
1893 if (a->acdirmin != b->acdirmin)
1894 goto Ebusy;
1895 if (a->acdirmax != b->acdirmax)
1896 goto Ebusy;
1897 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1898 goto Ebusy;
1899 return 1;
1900 Ebusy:
1901 return 0;
1902 }
1903
1904 struct nfs_sb_mountdata {
1905 struct nfs_server *server;
1906 int mntflags;
1907 };
1908
nfs_set_super(struct super_block * s,void * data)1909 static int nfs_set_super(struct super_block *s, void *data)
1910 {
1911 struct nfs_sb_mountdata *sb_mntdata = data;
1912 struct nfs_server *server = sb_mntdata->server;
1913 int ret;
1914
1915 s->s_flags = sb_mntdata->mntflags;
1916 s->s_fs_info = server;
1917 ret = set_anon_super(s, server);
1918 if (ret == 0)
1919 server->s_dev = s->s_dev;
1920 return ret;
1921 }
1922
nfs_compare_super_address(struct nfs_server * server1,struct nfs_server * server2)1923 static int nfs_compare_super_address(struct nfs_server *server1,
1924 struct nfs_server *server2)
1925 {
1926 struct sockaddr *sap1, *sap2;
1927
1928 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1929 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1930
1931 if (sap1->sa_family != sap2->sa_family)
1932 return 0;
1933
1934 switch (sap1->sa_family) {
1935 case AF_INET: {
1936 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1937 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1938 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1939 return 0;
1940 if (sin1->sin_port != sin2->sin_port)
1941 return 0;
1942 break;
1943 }
1944 case AF_INET6: {
1945 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1946 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1947 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1948 return 0;
1949 if (sin1->sin6_port != sin2->sin6_port)
1950 return 0;
1951 break;
1952 }
1953 default:
1954 return 0;
1955 }
1956
1957 return 1;
1958 }
1959
nfs_compare_super(struct super_block * sb,void * data)1960 static int nfs_compare_super(struct super_block *sb, void *data)
1961 {
1962 struct nfs_sb_mountdata *sb_mntdata = data;
1963 struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1964 int mntflags = sb_mntdata->mntflags;
1965
1966 if (!nfs_compare_super_address(old, server))
1967 return 0;
1968 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1969 if (old->flags & NFS_MOUNT_UNSHARED)
1970 return 0;
1971 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1972 return 0;
1973 return nfs_compare_mount_options(sb, server, mntflags);
1974 }
1975
nfs_bdi_register(struct nfs_server * server)1976 static int nfs_bdi_register(struct nfs_server *server)
1977 {
1978 return bdi_register_dev(&server->backing_dev_info, server->s_dev);
1979 }
1980
nfs_get_sb(struct file_system_type * fs_type,int flags,const char * dev_name,void * raw_data,struct vfsmount * mnt)1981 static int nfs_get_sb(struct file_system_type *fs_type,
1982 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1983 {
1984 struct nfs_server *server = NULL;
1985 struct super_block *s;
1986 struct nfs_parsed_mount_data *data;
1987 struct nfs_fh *mntfh;
1988 struct dentry *mntroot;
1989 int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1990 struct nfs_sb_mountdata sb_mntdata = {
1991 .mntflags = flags,
1992 };
1993 int error = -ENOMEM;
1994
1995 data = kzalloc(sizeof(*data), GFP_KERNEL);
1996 mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
1997 if (data == NULL || mntfh == NULL)
1998 goto out_free_fh;
1999
2000 security_init_mnt_opts(&data->lsm_opts);
2001
2002 /* Validate the mount data */
2003 error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2004 if (error < 0)
2005 goto out;
2006
2007 /* Get a volume representation */
2008 server = nfs_create_server(data, mntfh);
2009 if (IS_ERR(server)) {
2010 error = PTR_ERR(server);
2011 goto out;
2012 }
2013 sb_mntdata.server = server;
2014
2015 if (server->flags & NFS_MOUNT_UNSHARED)
2016 compare_super = NULL;
2017
2018 /* Get a superblock - note that we may end up sharing one that already exists */
2019 s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2020 if (IS_ERR(s)) {
2021 error = PTR_ERR(s);
2022 goto out_err_nosb;
2023 }
2024
2025 if (s->s_fs_info != server) {
2026 nfs_free_server(server);
2027 server = NULL;
2028 } else {
2029 error = nfs_bdi_register(server);
2030 if (error)
2031 goto error_splat_super;
2032 }
2033
2034 if (!s->s_root) {
2035 /* initial superblock/root creation */
2036 nfs_fill_super(s, data);
2037 }
2038
2039 mntroot = nfs_get_root(s, mntfh);
2040 if (IS_ERR(mntroot)) {
2041 error = PTR_ERR(mntroot);
2042 goto error_splat_super;
2043 }
2044
2045 error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2046 if (error)
2047 goto error_splat_root;
2048
2049 s->s_flags |= MS_ACTIVE;
2050 mnt->mnt_sb = s;
2051 mnt->mnt_root = mntroot;
2052 error = 0;
2053
2054 out:
2055 kfree(data->nfs_server.hostname);
2056 kfree(data->mount_server.hostname);
2057 security_free_mnt_opts(&data->lsm_opts);
2058 out_free_fh:
2059 kfree(mntfh);
2060 kfree(data);
2061 return error;
2062
2063 out_err_nosb:
2064 nfs_free_server(server);
2065 goto out;
2066
2067 error_splat_root:
2068 dput(mntroot);
2069 error_splat_super:
2070 up_write(&s->s_umount);
2071 deactivate_super(s);
2072 goto out;
2073 }
2074
2075 /*
2076 * Destroy an NFS2/3 superblock
2077 */
nfs_kill_super(struct super_block * s)2078 static void nfs_kill_super(struct super_block *s)
2079 {
2080 struct nfs_server *server = NFS_SB(s);
2081
2082 bdi_unregister(&server->backing_dev_info);
2083 kill_anon_super(s);
2084 nfs_free_server(server);
2085 }
2086
2087 /*
2088 * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2089 */
nfs_xdev_get_sb(struct file_system_type * fs_type,int flags,const char * dev_name,void * raw_data,struct vfsmount * mnt)2090 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
2091 const char *dev_name, void *raw_data,
2092 struct vfsmount *mnt)
2093 {
2094 struct nfs_clone_mount *data = raw_data;
2095 struct super_block *s;
2096 struct nfs_server *server;
2097 struct dentry *mntroot;
2098 int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2099 struct nfs_sb_mountdata sb_mntdata = {
2100 .mntflags = flags,
2101 };
2102 int error;
2103
2104 dprintk("--> nfs_xdev_get_sb()\n");
2105
2106 /* create a new volume representation */
2107 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2108 if (IS_ERR(server)) {
2109 error = PTR_ERR(server);
2110 goto out_err_noserver;
2111 }
2112 sb_mntdata.server = server;
2113
2114 if (server->flags & NFS_MOUNT_UNSHARED)
2115 compare_super = NULL;
2116
2117 /* Get a superblock - note that we may end up sharing one that already exists */
2118 s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2119 if (IS_ERR(s)) {
2120 error = PTR_ERR(s);
2121 goto out_err_nosb;
2122 }
2123
2124 if (s->s_fs_info != server) {
2125 nfs_free_server(server);
2126 server = NULL;
2127 } else {
2128 error = nfs_bdi_register(server);
2129 if (error)
2130 goto error_splat_super;
2131 }
2132
2133 if (!s->s_root) {
2134 /* initial superblock/root creation */
2135 nfs_clone_super(s, data->sb);
2136 }
2137
2138 mntroot = nfs_get_root(s, data->fh);
2139 if (IS_ERR(mntroot)) {
2140 error = PTR_ERR(mntroot);
2141 goto error_splat_super;
2142 }
2143 if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2144 dput(mntroot);
2145 error = -ESTALE;
2146 goto error_splat_super;
2147 }
2148
2149 s->s_flags |= MS_ACTIVE;
2150 mnt->mnt_sb = s;
2151 mnt->mnt_root = mntroot;
2152
2153 /* clone any lsm security options from the parent to the new sb */
2154 security_sb_clone_mnt_opts(data->sb, s);
2155
2156 dprintk("<-- nfs_xdev_get_sb() = 0\n");
2157 return 0;
2158
2159 out_err_nosb:
2160 nfs_free_server(server);
2161 out_err_noserver:
2162 dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
2163 return error;
2164
2165 error_splat_super:
2166 up_write(&s->s_umount);
2167 deactivate_super(s);
2168 dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
2169 return error;
2170 }
2171
2172 #ifdef CONFIG_NFS_V4
2173
2174 /*
2175 * Finish setting up a cloned NFS4 superblock
2176 */
nfs4_clone_super(struct super_block * sb,const struct super_block * old_sb)2177 static void nfs4_clone_super(struct super_block *sb,
2178 const struct super_block *old_sb)
2179 {
2180 sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2181 sb->s_blocksize = old_sb->s_blocksize;
2182 sb->s_maxbytes = old_sb->s_maxbytes;
2183 sb->s_time_gran = 1;
2184 sb->s_op = old_sb->s_op;
2185 nfs_initialise_sb(sb);
2186 }
2187
2188 /*
2189 * Set up an NFS4 superblock
2190 */
nfs4_fill_super(struct super_block * sb)2191 static void nfs4_fill_super(struct super_block *sb)
2192 {
2193 sb->s_time_gran = 1;
2194 sb->s_op = &nfs4_sops;
2195 nfs_initialise_sb(sb);
2196 }
2197
2198 /*
2199 * Validate NFSv4 mount options
2200 */
nfs4_validate_mount_data(void * options,struct nfs_parsed_mount_data * args,const char * dev_name)2201 static int nfs4_validate_mount_data(void *options,
2202 struct nfs_parsed_mount_data *args,
2203 const char *dev_name)
2204 {
2205 struct sockaddr_in *ap;
2206 struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2207 char *c;
2208
2209 if (data == NULL)
2210 goto out_no_data;
2211
2212 args->rsize = NFS_MAX_FILE_IO_SIZE;
2213 args->wsize = NFS_MAX_FILE_IO_SIZE;
2214 args->acregmin = NFS_DEF_ACREGMIN;
2215 args->acregmax = NFS_DEF_ACREGMAX;
2216 args->acdirmin = NFS_DEF_ACDIRMIN;
2217 args->acdirmax = NFS_DEF_ACDIRMAX;
2218 args->nfs_server.port = NFS_PORT; /* 2049 unless user set port= */
2219 args->auth_flavors[0] = RPC_AUTH_UNIX;
2220 args->auth_flavor_len = 0;
2221
2222 switch (data->version) {
2223 case 1:
2224 ap = (struct sockaddr_in *)&args->nfs_server.address;
2225 if (data->host_addrlen > sizeof(args->nfs_server.address))
2226 goto out_no_address;
2227 if (data->host_addrlen == 0)
2228 goto out_no_address;
2229 args->nfs_server.addrlen = data->host_addrlen;
2230 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
2231 return -EFAULT;
2232 if (!nfs_verify_server_address((struct sockaddr *)
2233 &args->nfs_server.address))
2234 goto out_no_address;
2235
2236 if (data->auth_flavourlen) {
2237 if (data->auth_flavourlen > 1)
2238 goto out_inval_auth;
2239 if (copy_from_user(&args->auth_flavors[0],
2240 data->auth_flavours,
2241 sizeof(args->auth_flavors[0])))
2242 return -EFAULT;
2243 }
2244
2245 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2246 if (IS_ERR(c))
2247 return PTR_ERR(c);
2248 args->nfs_server.hostname = c;
2249
2250 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2251 if (IS_ERR(c))
2252 return PTR_ERR(c);
2253 args->nfs_server.export_path = c;
2254 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2255
2256 c = strndup_user(data->client_addr.data, 16);
2257 if (IS_ERR(c))
2258 return PTR_ERR(c);
2259 args->client_address = c;
2260
2261 /*
2262 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2263 * can deal with.
2264 */
2265
2266 args->flags = data->flags & NFS4_MOUNT_FLAGMASK;
2267 args->rsize = data->rsize;
2268 args->wsize = data->wsize;
2269 args->timeo = data->timeo;
2270 args->retrans = data->retrans;
2271 args->acregmin = data->acregmin;
2272 args->acregmax = data->acregmax;
2273 args->acdirmin = data->acdirmin;
2274 args->acdirmax = data->acdirmax;
2275 args->nfs_server.protocol = data->proto;
2276 nfs_validate_transport_protocol(args);
2277
2278 break;
2279 default: {
2280 int status;
2281
2282 if (nfs_parse_mount_options((char *)options, args) == 0)
2283 return -EINVAL;
2284
2285 if (!nfs_verify_server_address((struct sockaddr *)
2286 &args->nfs_server.address))
2287 return -EINVAL;
2288
2289 nfs_set_port((struct sockaddr *)&args->nfs_server.address,
2290 args->nfs_server.port);
2291
2292 nfs_validate_transport_protocol(args);
2293
2294 if (args->auth_flavor_len > 1)
2295 goto out_inval_auth;
2296
2297 if (args->client_address == NULL)
2298 goto out_no_client_address;
2299
2300 status = nfs_parse_devname(dev_name,
2301 &args->nfs_server.hostname,
2302 NFS4_MAXNAMLEN,
2303 &args->nfs_server.export_path,
2304 NFS4_MAXPATHLEN);
2305 if (status < 0)
2306 return status;
2307
2308 break;
2309 }
2310 }
2311
2312 return 0;
2313
2314 out_no_data:
2315 dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2316 return -EINVAL;
2317
2318 out_inval_auth:
2319 dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2320 data->auth_flavourlen);
2321 return -EINVAL;
2322
2323 out_no_address:
2324 dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2325 return -EINVAL;
2326
2327 out_no_client_address:
2328 dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
2329 return -EINVAL;
2330 }
2331
2332 /*
2333 * Get the superblock for an NFS4 mountpoint
2334 */
nfs4_get_sb(struct file_system_type * fs_type,int flags,const char * dev_name,void * raw_data,struct vfsmount * mnt)2335 static int nfs4_get_sb(struct file_system_type *fs_type,
2336 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2337 {
2338 struct nfs_parsed_mount_data *data;
2339 struct super_block *s;
2340 struct nfs_server *server;
2341 struct nfs_fh *mntfh;
2342 struct dentry *mntroot;
2343 int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2344 struct nfs_sb_mountdata sb_mntdata = {
2345 .mntflags = flags,
2346 };
2347 int error = -ENOMEM;
2348
2349 data = kzalloc(sizeof(*data), GFP_KERNEL);
2350 mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2351 if (data == NULL || mntfh == NULL)
2352 goto out_free_fh;
2353
2354 security_init_mnt_opts(&data->lsm_opts);
2355
2356 /* Validate the mount data */
2357 error = nfs4_validate_mount_data(raw_data, data, dev_name);
2358 if (error < 0)
2359 goto out;
2360
2361 /* Get a volume representation */
2362 server = nfs4_create_server(data, mntfh);
2363 if (IS_ERR(server)) {
2364 error = PTR_ERR(server);
2365 goto out;
2366 }
2367 sb_mntdata.server = server;
2368
2369 if (server->flags & NFS4_MOUNT_UNSHARED)
2370 compare_super = NULL;
2371
2372 /* Get a superblock - note that we may end up sharing one that already exists */
2373 s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2374 if (IS_ERR(s)) {
2375 error = PTR_ERR(s);
2376 goto out_free;
2377 }
2378
2379 if (s->s_fs_info != server) {
2380 nfs_free_server(server);
2381 server = NULL;
2382 } else {
2383 error = nfs_bdi_register(server);
2384 if (error)
2385 goto error_splat_super;
2386 }
2387
2388 if (!s->s_root) {
2389 /* initial superblock/root creation */
2390 nfs4_fill_super(s);
2391 }
2392
2393 mntroot = nfs4_get_root(s, mntfh);
2394 if (IS_ERR(mntroot)) {
2395 error = PTR_ERR(mntroot);
2396 goto error_splat_super;
2397 }
2398
2399 error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2400 if (error)
2401 goto error_splat_root;
2402
2403 s->s_flags |= MS_ACTIVE;
2404 mnt->mnt_sb = s;
2405 mnt->mnt_root = mntroot;
2406 error = 0;
2407
2408 out:
2409 kfree(data->client_address);
2410 kfree(data->nfs_server.export_path);
2411 kfree(data->nfs_server.hostname);
2412 security_free_mnt_opts(&data->lsm_opts);
2413 out_free_fh:
2414 kfree(mntfh);
2415 kfree(data);
2416 return error;
2417
2418 out_free:
2419 nfs_free_server(server);
2420 goto out;
2421
2422 error_splat_root:
2423 dput(mntroot);
2424 error_splat_super:
2425 up_write(&s->s_umount);
2426 deactivate_super(s);
2427 goto out;
2428 }
2429
nfs4_kill_super(struct super_block * sb)2430 static void nfs4_kill_super(struct super_block *sb)
2431 {
2432 struct nfs_server *server = NFS_SB(sb);
2433
2434 nfs_super_return_all_delegations(sb);
2435 kill_anon_super(sb);
2436
2437 nfs4_renewd_prepare_shutdown(server);
2438 nfs_free_server(server);
2439 }
2440
2441 /*
2442 * Clone an NFS4 server record on xdev traversal (FSID-change)
2443 */
nfs4_xdev_get_sb(struct file_system_type * fs_type,int flags,const char * dev_name,void * raw_data,struct vfsmount * mnt)2444 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2445 const char *dev_name, void *raw_data,
2446 struct vfsmount *mnt)
2447 {
2448 struct nfs_clone_mount *data = raw_data;
2449 struct super_block *s;
2450 struct nfs_server *server;
2451 struct dentry *mntroot;
2452 int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2453 struct nfs_sb_mountdata sb_mntdata = {
2454 .mntflags = flags,
2455 };
2456 int error;
2457
2458 dprintk("--> nfs4_xdev_get_sb()\n");
2459
2460 /* create a new volume representation */
2461 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2462 if (IS_ERR(server)) {
2463 error = PTR_ERR(server);
2464 goto out_err_noserver;
2465 }
2466 sb_mntdata.server = server;
2467
2468 if (server->flags & NFS4_MOUNT_UNSHARED)
2469 compare_super = NULL;
2470
2471 /* Get a superblock - note that we may end up sharing one that already exists */
2472 s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2473 if (IS_ERR(s)) {
2474 error = PTR_ERR(s);
2475 goto out_err_nosb;
2476 }
2477
2478 if (s->s_fs_info != server) {
2479 nfs_free_server(server);
2480 server = NULL;
2481 } else {
2482 error = nfs_bdi_register(server);
2483 if (error)
2484 goto error_splat_super;
2485 }
2486
2487 if (!s->s_root) {
2488 /* initial superblock/root creation */
2489 nfs4_clone_super(s, data->sb);
2490 }
2491
2492 mntroot = nfs4_get_root(s, data->fh);
2493 if (IS_ERR(mntroot)) {
2494 error = PTR_ERR(mntroot);
2495 goto error_splat_super;
2496 }
2497 if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2498 dput(mntroot);
2499 error = -ESTALE;
2500 goto error_splat_super;
2501 }
2502
2503 s->s_flags |= MS_ACTIVE;
2504 mnt->mnt_sb = s;
2505 mnt->mnt_root = mntroot;
2506
2507 security_sb_clone_mnt_opts(data->sb, s);
2508
2509 dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2510 return 0;
2511
2512 out_err_nosb:
2513 nfs_free_server(server);
2514 out_err_noserver:
2515 dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2516 return error;
2517
2518 error_splat_super:
2519 up_write(&s->s_umount);
2520 deactivate_super(s);
2521 dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2522 return error;
2523 }
2524
2525 /*
2526 * Create an NFS4 server record on referral traversal
2527 */
nfs4_referral_get_sb(struct file_system_type * fs_type,int flags,const char * dev_name,void * raw_data,struct vfsmount * mnt)2528 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2529 const char *dev_name, void *raw_data,
2530 struct vfsmount *mnt)
2531 {
2532 struct nfs_clone_mount *data = raw_data;
2533 struct super_block *s;
2534 struct nfs_server *server;
2535 struct dentry *mntroot;
2536 struct nfs_fh mntfh;
2537 int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2538 struct nfs_sb_mountdata sb_mntdata = {
2539 .mntflags = flags,
2540 };
2541 int error;
2542
2543 dprintk("--> nfs4_referral_get_sb()\n");
2544
2545 /* create a new volume representation */
2546 server = nfs4_create_referral_server(data, &mntfh);
2547 if (IS_ERR(server)) {
2548 error = PTR_ERR(server);
2549 goto out_err_noserver;
2550 }
2551 sb_mntdata.server = server;
2552
2553 if (server->flags & NFS4_MOUNT_UNSHARED)
2554 compare_super = NULL;
2555
2556 /* Get a superblock - note that we may end up sharing one that already exists */
2557 s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2558 if (IS_ERR(s)) {
2559 error = PTR_ERR(s);
2560 goto out_err_nosb;
2561 }
2562
2563 if (s->s_fs_info != server) {
2564 nfs_free_server(server);
2565 server = NULL;
2566 } else {
2567 error = nfs_bdi_register(server);
2568 if (error)
2569 goto error_splat_super;
2570 }
2571
2572 if (!s->s_root) {
2573 /* initial superblock/root creation */
2574 nfs4_fill_super(s);
2575 }
2576
2577 mntroot = nfs4_get_root(s, &mntfh);
2578 if (IS_ERR(mntroot)) {
2579 error = PTR_ERR(mntroot);
2580 goto error_splat_super;
2581 }
2582 if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2583 dput(mntroot);
2584 error = -ESTALE;
2585 goto error_splat_super;
2586 }
2587
2588 s->s_flags |= MS_ACTIVE;
2589 mnt->mnt_sb = s;
2590 mnt->mnt_root = mntroot;
2591
2592 security_sb_clone_mnt_opts(data->sb, s);
2593
2594 dprintk("<-- nfs4_referral_get_sb() = 0\n");
2595 return 0;
2596
2597 out_err_nosb:
2598 nfs_free_server(server);
2599 out_err_noserver:
2600 dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2601 return error;
2602
2603 error_splat_super:
2604 up_write(&s->s_umount);
2605 deactivate_super(s);
2606 dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2607 return error;
2608 }
2609
2610 #endif /* CONFIG_NFS_V4 */
2611