switch cachefiles to kern_path()
[linux-2.6.git] / fs / nfs / super.c
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/mnt_namespace.h>
46 #include <linux/namei.h>
47 #include <linux/nfs_idmap.h>
48 #include <linux/vfs.h>
49 #include <linux/inet.h>
50 #include <linux/in6.h>
51 #include <net/ipv6.h>
52 #include <linux/netdevice.h>
53 #include <linux/nfs_xdr.h>
54 #include <linux/magic.h>
55 #include <linux/parser.h>
56
57 #include <asm/system.h>
58 #include <asm/uaccess.h>
59
60 #include "nfs4_fs.h"
61 #include "callback.h"
62 #include "delegation.h"
63 #include "iostat.h"
64 #include "internal.h"
65 #include "fscache.h"
66
67 #define NFSDBG_FACILITY         NFSDBG_VFS
68
69 enum {
70         /* Mount options that take no arguments */
71         Opt_soft, Opt_hard,
72         Opt_posix, Opt_noposix,
73         Opt_cto, Opt_nocto,
74         Opt_ac, Opt_noac,
75         Opt_lock, Opt_nolock,
76         Opt_v2, Opt_v3, Opt_v4,
77         Opt_udp, Opt_tcp, Opt_rdma,
78         Opt_acl, Opt_noacl,
79         Opt_rdirplus, Opt_nordirplus,
80         Opt_sharecache, Opt_nosharecache,
81         Opt_resvport, Opt_noresvport,
82         Opt_fscache, Opt_nofscache,
83
84         /* Mount options that take integer arguments */
85         Opt_port,
86         Opt_rsize, Opt_wsize, Opt_bsize,
87         Opt_timeo, Opt_retrans,
88         Opt_acregmin, Opt_acregmax,
89         Opt_acdirmin, Opt_acdirmax,
90         Opt_actimeo,
91         Opt_namelen,
92         Opt_mountport,
93         Opt_mountvers,
94         Opt_nfsvers,
95         Opt_minorversion,
96
97         /* Mount options that take string arguments */
98         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
99         Opt_addr, Opt_mountaddr, Opt_clientaddr,
100         Opt_lookupcache,
101         Opt_fscache_uniq,
102
103         /* Special mount options */
104         Opt_userspace, Opt_deprecated, Opt_sloppy,
105
106         Opt_err
107 };
108
109 static const match_table_t nfs_mount_option_tokens = {
110         { Opt_userspace, "bg" },
111         { Opt_userspace, "fg" },
112         { Opt_userspace, "retry=%s" },
113
114         { Opt_sloppy, "sloppy" },
115
116         { Opt_soft, "soft" },
117         { Opt_hard, "hard" },
118         { Opt_deprecated, "intr" },
119         { Opt_deprecated, "nointr" },
120         { Opt_posix, "posix" },
121         { Opt_noposix, "noposix" },
122         { Opt_cto, "cto" },
123         { Opt_nocto, "nocto" },
124         { Opt_ac, "ac" },
125         { Opt_noac, "noac" },
126         { Opt_lock, "lock" },
127         { Opt_nolock, "nolock" },
128         { Opt_v2, "v2" },
129         { Opt_v3, "v3" },
130         { Opt_v4, "v4" },
131         { Opt_udp, "udp" },
132         { Opt_tcp, "tcp" },
133         { Opt_rdma, "rdma" },
134         { Opt_acl, "acl" },
135         { Opt_noacl, "noacl" },
136         { Opt_rdirplus, "rdirplus" },
137         { Opt_nordirplus, "nordirplus" },
138         { Opt_sharecache, "sharecache" },
139         { Opt_nosharecache, "nosharecache" },
140         { Opt_resvport, "resvport" },
141         { Opt_noresvport, "noresvport" },
142         { Opt_fscache, "fsc" },
143         { Opt_fscache_uniq, "fsc=%s" },
144         { Opt_nofscache, "nofsc" },
145
146         { Opt_port, "port=%s" },
147         { Opt_rsize, "rsize=%s" },
148         { Opt_wsize, "wsize=%s" },
149         { Opt_bsize, "bsize=%s" },
150         { Opt_timeo, "timeo=%s" },
151         { Opt_retrans, "retrans=%s" },
152         { Opt_acregmin, "acregmin=%s" },
153         { Opt_acregmax, "acregmax=%s" },
154         { Opt_acdirmin, "acdirmin=%s" },
155         { Opt_acdirmax, "acdirmax=%s" },
156         { Opt_actimeo, "actimeo=%s" },
157         { Opt_namelen, "namlen=%s" },
158         { Opt_mountport, "mountport=%s" },
159         { Opt_mountvers, "mountvers=%s" },
160         { Opt_nfsvers, "nfsvers=%s" },
161         { Opt_nfsvers, "vers=%s" },
162         { Opt_minorversion, "minorversion=%s" },
163
164         { Opt_sec, "sec=%s" },
165         { Opt_proto, "proto=%s" },
166         { Opt_mountproto, "mountproto=%s" },
167         { Opt_addr, "addr=%s" },
168         { Opt_clientaddr, "clientaddr=%s" },
169         { Opt_mounthost, "mounthost=%s" },
170         { Opt_mountaddr, "mountaddr=%s" },
171
172         { Opt_lookupcache, "lookupcache=%s" },
173
174         { Opt_err, NULL }
175 };
176
177 enum {
178         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
179
180         Opt_xprt_err
181 };
182
183 static const match_table_t nfs_xprt_protocol_tokens = {
184         { Opt_xprt_udp, "udp" },
185         { Opt_xprt_udp6, "udp6" },
186         { Opt_xprt_tcp, "tcp" },
187         { Opt_xprt_tcp6, "tcp6" },
188         { Opt_xprt_rdma, "rdma" },
189
190         { Opt_xprt_err, NULL }
191 };
192
193 enum {
194         Opt_sec_none, Opt_sec_sys,
195         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
196         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
197         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
198
199         Opt_sec_err
200 };
201
202 static const match_table_t nfs_secflavor_tokens = {
203         { Opt_sec_none, "none" },
204         { Opt_sec_none, "null" },
205         { Opt_sec_sys, "sys" },
206
207         { Opt_sec_krb5, "krb5" },
208         { Opt_sec_krb5i, "krb5i" },
209         { Opt_sec_krb5p, "krb5p" },
210
211         { Opt_sec_lkey, "lkey" },
212         { Opt_sec_lkeyi, "lkeyi" },
213         { Opt_sec_lkeyp, "lkeyp" },
214
215         { Opt_sec_spkm, "spkm3" },
216         { Opt_sec_spkmi, "spkm3i" },
217         { Opt_sec_spkmp, "spkm3p" },
218
219         { Opt_sec_err, NULL }
220 };
221
222 enum {
223         Opt_lookupcache_all, Opt_lookupcache_positive,
224         Opt_lookupcache_none,
225
226         Opt_lookupcache_err
227 };
228
229 static match_table_t nfs_lookupcache_tokens = {
230         { Opt_lookupcache_all, "all" },
231         { Opt_lookupcache_positive, "pos" },
232         { Opt_lookupcache_positive, "positive" },
233         { Opt_lookupcache_none, "none" },
234
235         { Opt_lookupcache_err, NULL }
236 };
237
238
239 static void nfs_umount_begin(struct super_block *);
240 static int  nfs_statfs(struct dentry *, struct kstatfs *);
241 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
242 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
243 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
244 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
245                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
246 static void nfs_kill_super(struct super_block *);
247 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
248
249 static struct file_system_type nfs_fs_type = {
250         .owner          = THIS_MODULE,
251         .name           = "nfs",
252         .get_sb         = nfs_get_sb,
253         .kill_sb        = nfs_kill_super,
254         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
255 };
256
257 struct file_system_type nfs_xdev_fs_type = {
258         .owner          = THIS_MODULE,
259         .name           = "nfs",
260         .get_sb         = nfs_xdev_get_sb,
261         .kill_sb        = nfs_kill_super,
262         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
263 };
264
265 static const struct super_operations nfs_sops = {
266         .alloc_inode    = nfs_alloc_inode,
267         .destroy_inode  = nfs_destroy_inode,
268         .write_inode    = nfs_write_inode,
269         .statfs         = nfs_statfs,
270         .clear_inode    = nfs_clear_inode,
271         .umount_begin   = nfs_umount_begin,
272         .show_options   = nfs_show_options,
273         .show_stats     = nfs_show_stats,
274         .remount_fs     = nfs_remount,
275 };
276
277 #ifdef CONFIG_NFS_V4
278 static int nfs4_validate_text_mount_data(void *options,
279         struct nfs_parsed_mount_data *args, const char *dev_name);
280 static int nfs4_try_mount(int flags, const char *dev_name,
281         struct nfs_parsed_mount_data *data, struct vfsmount *mnt);
282 static int nfs4_get_sb(struct file_system_type *fs_type,
283         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
284 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
285         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
286 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
287         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
288 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
289         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
290 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
291         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
292 static void nfs4_kill_super(struct super_block *sb);
293
294 static struct file_system_type nfs4_fs_type = {
295         .owner          = THIS_MODULE,
296         .name           = "nfs4",
297         .get_sb         = nfs4_get_sb,
298         .kill_sb        = nfs4_kill_super,
299         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
300 };
301
302 static struct file_system_type nfs4_remote_fs_type = {
303         .owner          = THIS_MODULE,
304         .name           = "nfs4",
305         .get_sb         = nfs4_remote_get_sb,
306         .kill_sb        = nfs4_kill_super,
307         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
308 };
309
310 struct file_system_type nfs4_xdev_fs_type = {
311         .owner          = THIS_MODULE,
312         .name           = "nfs4",
313         .get_sb         = nfs4_xdev_get_sb,
314         .kill_sb        = nfs4_kill_super,
315         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
316 };
317
318 static struct file_system_type nfs4_remote_referral_fs_type = {
319         .owner          = THIS_MODULE,
320         .name           = "nfs4",
321         .get_sb         = nfs4_remote_referral_get_sb,
322         .kill_sb        = nfs4_kill_super,
323         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
324 };
325
326 struct file_system_type nfs4_referral_fs_type = {
327         .owner          = THIS_MODULE,
328         .name           = "nfs4",
329         .get_sb         = nfs4_referral_get_sb,
330         .kill_sb        = nfs4_kill_super,
331         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
332 };
333
334 static const struct super_operations nfs4_sops = {
335         .alloc_inode    = nfs_alloc_inode,
336         .destroy_inode  = nfs_destroy_inode,
337         .write_inode    = nfs_write_inode,
338         .statfs         = nfs_statfs,
339         .clear_inode    = nfs4_clear_inode,
340         .umount_begin   = nfs_umount_begin,
341         .show_options   = nfs_show_options,
342         .show_stats     = nfs_show_stats,
343         .remount_fs     = nfs_remount,
344 };
345 #endif
346
347 static struct shrinker acl_shrinker = {
348         .shrink         = nfs_access_cache_shrinker,
349         .seeks          = DEFAULT_SEEKS,
350 };
351
352 /*
353  * Register the NFS filesystems
354  */
355 int __init register_nfs_fs(void)
356 {
357         int ret;
358
359         ret = register_filesystem(&nfs_fs_type);
360         if (ret < 0)
361                 goto error_0;
362
363         ret = nfs_register_sysctl();
364         if (ret < 0)
365                 goto error_1;
366 #ifdef CONFIG_NFS_V4
367         ret = register_filesystem(&nfs4_fs_type);
368         if (ret < 0)
369                 goto error_2;
370 #endif
371         register_shrinker(&acl_shrinker);
372         return 0;
373
374 #ifdef CONFIG_NFS_V4
375 error_2:
376         nfs_unregister_sysctl();
377 #endif
378 error_1:
379         unregister_filesystem(&nfs_fs_type);
380 error_0:
381         return ret;
382 }
383
384 /*
385  * Unregister the NFS filesystems
386  */
387 void __exit unregister_nfs_fs(void)
388 {
389         unregister_shrinker(&acl_shrinker);
390 #ifdef CONFIG_NFS_V4
391         unregister_filesystem(&nfs4_fs_type);
392 #endif
393         nfs_unregister_sysctl();
394         unregister_filesystem(&nfs_fs_type);
395 }
396
397 void nfs_sb_active(struct super_block *sb)
398 {
399         struct nfs_server *server = NFS_SB(sb);
400
401         if (atomic_inc_return(&server->active) == 1)
402                 atomic_inc(&sb->s_active);
403 }
404
405 void nfs_sb_deactive(struct super_block *sb)
406 {
407         struct nfs_server *server = NFS_SB(sb);
408
409         if (atomic_dec_and_test(&server->active))
410                 deactivate_super(sb);
411 }
412
413 /*
414  * Deliver file system statistics to userspace
415  */
416 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
417 {
418         struct nfs_server *server = NFS_SB(dentry->d_sb);
419         unsigned char blockbits;
420         unsigned long blockres;
421         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
422         struct nfs_fattr fattr;
423         struct nfs_fsstat res = {
424                         .fattr = &fattr,
425         };
426         int error;
427
428         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
429         if (error < 0)
430                 goto out_err;
431         buf->f_type = NFS_SUPER_MAGIC;
432
433         /*
434          * Current versions of glibc do not correctly handle the
435          * case where f_frsize != f_bsize.  Eventually we want to
436          * report the value of wtmult in this field.
437          */
438         buf->f_frsize = dentry->d_sb->s_blocksize;
439
440         /*
441          * On most *nix systems, f_blocks, f_bfree, and f_bavail
442          * are reported in units of f_frsize.  Linux hasn't had
443          * an f_frsize field in its statfs struct until recently,
444          * thus historically Linux's sys_statfs reports these
445          * fields in units of f_bsize.
446          */
447         buf->f_bsize = dentry->d_sb->s_blocksize;
448         blockbits = dentry->d_sb->s_blocksize_bits;
449         blockres = (1 << blockbits) - 1;
450         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
451         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
452         buf->f_bavail = (res.abytes + blockres) >> blockbits;
453
454         buf->f_files = res.tfiles;
455         buf->f_ffree = res.afiles;
456
457         buf->f_namelen = server->namelen;
458
459         return 0;
460
461  out_err:
462         dprintk("%s: statfs error = %d\n", __func__, -error);
463         return error;
464 }
465
466 /*
467  * Map the security flavour number to a name
468  */
469 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
470 {
471         static const struct {
472                 rpc_authflavor_t flavour;
473                 const char *str;
474         } sec_flavours[] = {
475                 { RPC_AUTH_NULL, "null" },
476                 { RPC_AUTH_UNIX, "sys" },
477                 { RPC_AUTH_GSS_KRB5, "krb5" },
478                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
479                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
480                 { RPC_AUTH_GSS_LKEY, "lkey" },
481                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
482                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
483                 { RPC_AUTH_GSS_SPKM, "spkm" },
484                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
485                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
486                 { UINT_MAX, "unknown" }
487         };
488         int i;
489
490         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
491                 if (sec_flavours[i].flavour == flavour)
492                         break;
493         }
494         return sec_flavours[i].str;
495 }
496
497 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
498                                   int showdefaults)
499 {
500         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
501
502         seq_printf(m, ",mountproto=");
503         switch (sap->sa_family) {
504         case AF_INET:
505                 switch (nfss->mountd_protocol) {
506                 case IPPROTO_UDP:
507                         seq_printf(m, RPCBIND_NETID_UDP);
508                         break;
509                 case IPPROTO_TCP:
510                         seq_printf(m, RPCBIND_NETID_TCP);
511                         break;
512                 default:
513                         if (showdefaults)
514                                 seq_printf(m, "auto");
515                 }
516                 break;
517         case AF_INET6:
518                 switch (nfss->mountd_protocol) {
519                 case IPPROTO_UDP:
520                         seq_printf(m, RPCBIND_NETID_UDP6);
521                         break;
522                 case IPPROTO_TCP:
523                         seq_printf(m, RPCBIND_NETID_TCP6);
524                         break;
525                 default:
526                         if (showdefaults)
527                                 seq_printf(m, "auto");
528                 }
529                 break;
530         default:
531                 if (showdefaults)
532                         seq_printf(m, "auto");
533         }
534 }
535
536 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
537                                     int showdefaults)
538 {
539         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
540
541         switch (sap->sa_family) {
542         case AF_INET: {
543                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
544                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
545                 break;
546         }
547         case AF_INET6: {
548                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
549                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
550                 break;
551         }
552         default:
553                 if (showdefaults)
554                         seq_printf(m, ",mountaddr=unspecified");
555         }
556
557         if (nfss->mountd_version || showdefaults)
558                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
559         if (nfss->mountd_port || showdefaults)
560                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
561
562         nfs_show_mountd_netid(m, nfss, showdefaults);
563 }
564
565 /*
566  * Describe the mount options in force on this server representation
567  */
568 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
569                                    int showdefaults)
570 {
571         static const struct proc_nfs_info {
572                 int flag;
573                 const char *str;
574                 const char *nostr;
575         } nfs_info[] = {
576                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
577                 { NFS_MOUNT_POSIX, ",posix", "" },
578                 { NFS_MOUNT_NOCTO, ",nocto", "" },
579                 { NFS_MOUNT_NOAC, ",noac", "" },
580                 { NFS_MOUNT_NONLM, ",nolock", "" },
581                 { NFS_MOUNT_NOACL, ",noacl", "" },
582                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
583                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
584                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
585                 { 0, NULL, NULL }
586         };
587         const struct proc_nfs_info *nfs_infop;
588         struct nfs_client *clp = nfss->nfs_client;
589         u32 version = clp->rpc_ops->version;
590
591         seq_printf(m, ",vers=%u", version);
592         seq_printf(m, ",rsize=%u", nfss->rsize);
593         seq_printf(m, ",wsize=%u", nfss->wsize);
594         if (nfss->bsize != 0)
595                 seq_printf(m, ",bsize=%u", nfss->bsize);
596         seq_printf(m, ",namlen=%u", nfss->namelen);
597         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
598                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
599         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
600                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
601         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
602                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
603         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
604                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
605         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
606                 if (nfss->flags & nfs_infop->flag)
607                         seq_puts(m, nfs_infop->str);
608                 else
609                         seq_puts(m, nfs_infop->nostr);
610         }
611         seq_printf(m, ",proto=%s",
612                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
613         if (version == 4) {
614                 if (nfss->port != NFS_PORT)
615                         seq_printf(m, ",port=%u", nfss->port);
616         } else
617                 if (nfss->port)
618                         seq_printf(m, ",port=%u", nfss->port);
619
620         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
621         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
622         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
623
624         if (version != 4)
625                 nfs_show_mountd_options(m, nfss, showdefaults);
626
627 #ifdef CONFIG_NFS_V4
628         if (clp->rpc_ops->version == 4)
629                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
630 #endif
631         if (nfss->options & NFS_OPTION_FSCACHE)
632                 seq_printf(m, ",fsc");
633 }
634
635 /*
636  * Describe the mount options on this VFS mountpoint
637  */
638 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
639 {
640         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
641
642         nfs_show_mount_options(m, nfss, 0);
643
644         seq_printf(m, ",addr=%s",
645                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
646                                                         RPC_DISPLAY_ADDR));
647
648         return 0;
649 }
650
651 /*
652  * Present statistical information for this VFS mountpoint
653  */
654 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
655 {
656         int i, cpu;
657         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
658         struct rpc_auth *auth = nfss->client->cl_auth;
659         struct nfs_iostats totals = { };
660
661         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
662
663         /*
664          * Display all mount option settings
665          */
666         seq_printf(m, "\n\topts:\t");
667         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
668         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
669         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
670         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
671         nfs_show_mount_options(m, nfss, 1);
672
673         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
674
675         seq_printf(m, "\n\tcaps:\t");
676         seq_printf(m, "caps=0x%x", nfss->caps);
677         seq_printf(m, ",wtmult=%u", nfss->wtmult);
678         seq_printf(m, ",dtsize=%u", nfss->dtsize);
679         seq_printf(m, ",bsize=%u", nfss->bsize);
680         seq_printf(m, ",namlen=%u", nfss->namelen);
681
682 #ifdef CONFIG_NFS_V4
683         if (nfss->nfs_client->rpc_ops->version == 4) {
684                 seq_printf(m, "\n\tnfsv4:\t");
685                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
686                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
687                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
688         }
689 #endif
690
691         /*
692          * Display security flavor in effect for this mount
693          */
694         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
695         if (auth->au_flavor)
696                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
697
698         /*
699          * Display superblock I/O counters
700          */
701         for_each_possible_cpu(cpu) {
702                 struct nfs_iostats *stats;
703
704                 preempt_disable();
705                 stats = per_cpu_ptr(nfss->io_stats, cpu);
706
707                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
708                         totals.events[i] += stats->events[i];
709                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
710                         totals.bytes[i] += stats->bytes[i];
711 #ifdef CONFIG_NFS_FSCACHE
712                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
713                         totals.fscache[i] += stats->fscache[i];
714 #endif
715
716                 preempt_enable();
717         }
718
719         seq_printf(m, "\n\tevents:\t");
720         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
721                 seq_printf(m, "%lu ", totals.events[i]);
722         seq_printf(m, "\n\tbytes:\t");
723         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
724                 seq_printf(m, "%Lu ", totals.bytes[i]);
725 #ifdef CONFIG_NFS_FSCACHE
726         if (nfss->options & NFS_OPTION_FSCACHE) {
727                 seq_printf(m, "\n\tfsc:\t");
728                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
729                         seq_printf(m, "%Lu ", totals.bytes[i]);
730         }
731 #endif
732         seq_printf(m, "\n");
733
734         rpc_print_iostats(m, nfss->client);
735
736         return 0;
737 }
738
739 /*
740  * Begin unmount by attempting to remove all automounted mountpoints we added
741  * in response to xdev traversals and referrals
742  */
743 static void nfs_umount_begin(struct super_block *sb)
744 {
745         struct nfs_server *server;
746         struct rpc_clnt *rpc;
747
748         server = NFS_SB(sb);
749         /* -EIO all pending I/O */
750         rpc = server->client_acl;
751         if (!IS_ERR(rpc))
752                 rpc_killall_tasks(rpc);
753         rpc = server->client;
754         if (!IS_ERR(rpc))
755                 rpc_killall_tasks(rpc);
756 }
757
758 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
759 {
760         struct nfs_parsed_mount_data *data;
761
762         data = kzalloc(sizeof(*data), GFP_KERNEL);
763         if (data) {
764                 data->acregmin          = NFS_DEF_ACREGMIN;
765                 data->acregmax          = NFS_DEF_ACREGMAX;
766                 data->acdirmin          = NFS_DEF_ACDIRMIN;
767                 data->acdirmax          = NFS_DEF_ACDIRMAX;
768                 data->mount_server.port = NFS_UNSPEC_PORT;
769                 data->nfs_server.port   = NFS_UNSPEC_PORT;
770                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
771                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
772                 data->auth_flavor_len   = 1;
773                 data->version           = version;
774                 data->minorversion      = 0;
775         }
776         return data;
777 }
778
779 /*
780  * Sanity-check a server address provided by the mount command.
781  *
782  * Address family must be initialized, and address must not be
783  * the ANY address for that family.
784  */
785 static int nfs_verify_server_address(struct sockaddr *addr)
786 {
787         switch (addr->sa_family) {
788         case AF_INET: {
789                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
790                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
791         }
792         case AF_INET6: {
793                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
794                 return !ipv6_addr_any(sa);
795         }
796         }
797
798         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
799         return 0;
800 }
801
802 /*
803  * Select between a default port value and a user-specified port value.
804  * If a zero value is set, then autobind will be used.
805  */
806 static void nfs_set_port(struct sockaddr *sap, int *port,
807                                  const unsigned short default_port)
808 {
809         if (*port == NFS_UNSPEC_PORT)
810                 *port = default_port;
811
812         rpc_set_port(sap, *port);
813 }
814
815 /*
816  * Sanity check the NFS transport protocol.
817  *
818  */
819 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
820 {
821         switch (mnt->nfs_server.protocol) {
822         case XPRT_TRANSPORT_UDP:
823         case XPRT_TRANSPORT_TCP:
824         case XPRT_TRANSPORT_RDMA:
825                 break;
826         default:
827                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
828         }
829 }
830
831 /*
832  * For text based NFSv2/v3 mounts, the mount protocol transport default
833  * settings should depend upon the specified NFS transport.
834  */
835 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
836 {
837         nfs_validate_transport_protocol(mnt);
838
839         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
840             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
841                         return;
842         switch (mnt->nfs_server.protocol) {
843         case XPRT_TRANSPORT_UDP:
844                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
845                 break;
846         case XPRT_TRANSPORT_TCP:
847         case XPRT_TRANSPORT_RDMA:
848                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
849         }
850 }
851
852 /*
853  * Parse the value of the 'sec=' option.
854  */
855 static int nfs_parse_security_flavors(char *value,
856                                       struct nfs_parsed_mount_data *mnt)
857 {
858         substring_t args[MAX_OPT_ARGS];
859
860         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
861
862         switch (match_token(value, nfs_secflavor_tokens, args)) {
863         case Opt_sec_none:
864                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
865                 break;
866         case Opt_sec_sys:
867                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
868                 break;
869         case Opt_sec_krb5:
870                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
871                 break;
872         case Opt_sec_krb5i:
873                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
874                 break;
875         case Opt_sec_krb5p:
876                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
877                 break;
878         case Opt_sec_lkey:
879                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
880                 break;
881         case Opt_sec_lkeyi:
882                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
883                 break;
884         case Opt_sec_lkeyp:
885                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
886                 break;
887         case Opt_sec_spkm:
888                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
889                 break;
890         case Opt_sec_spkmi:
891                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
892                 break;
893         case Opt_sec_spkmp:
894                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
895                 break;
896         default:
897                 return 0;
898         }
899
900         mnt->auth_flavor_len = 1;
901         return 1;
902 }
903
904 /*
905  * Error-check and convert a string of mount options from user space into
906  * a data structure.  The whole mount string is processed; bad options are
907  * skipped as they are encountered.  If there were no errors, return 1;
908  * otherwise return 0 (zero).
909  */
910 static int nfs_parse_mount_options(char *raw,
911                                    struct nfs_parsed_mount_data *mnt)
912 {
913         char *p, *string, *secdata;
914         int rc, sloppy = 0, invalid_option = 0;
915         unsigned short protofamily = AF_UNSPEC;
916         unsigned short mountfamily = AF_UNSPEC;
917
918         if (!raw) {
919                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
920                 return 1;
921         }
922         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
923
924         secdata = alloc_secdata();
925         if (!secdata)
926                 goto out_nomem;
927
928         rc = security_sb_copy_data(raw, secdata);
929         if (rc)
930                 goto out_security_failure;
931
932         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
933         if (rc)
934                 goto out_security_failure;
935
936         free_secdata(secdata);
937
938         while ((p = strsep(&raw, ",")) != NULL) {
939                 substring_t args[MAX_OPT_ARGS];
940                 unsigned long option;
941                 int token;
942
943                 if (!*p)
944                         continue;
945
946                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
947
948                 token = match_token(p, nfs_mount_option_tokens, args);
949                 switch (token) {
950
951                 /*
952                  * boolean options:  foo/nofoo
953                  */
954                 case Opt_soft:
955                         mnt->flags |= NFS_MOUNT_SOFT;
956                         break;
957                 case Opt_hard:
958                         mnt->flags &= ~NFS_MOUNT_SOFT;
959                         break;
960                 case Opt_posix:
961                         mnt->flags |= NFS_MOUNT_POSIX;
962                         break;
963                 case Opt_noposix:
964                         mnt->flags &= ~NFS_MOUNT_POSIX;
965                         break;
966                 case Opt_cto:
967                         mnt->flags &= ~NFS_MOUNT_NOCTO;
968                         break;
969                 case Opt_nocto:
970                         mnt->flags |= NFS_MOUNT_NOCTO;
971                         break;
972                 case Opt_ac:
973                         mnt->flags &= ~NFS_MOUNT_NOAC;
974                         break;
975                 case Opt_noac:
976                         mnt->flags |= NFS_MOUNT_NOAC;
977                         break;
978                 case Opt_lock:
979                         mnt->flags &= ~NFS_MOUNT_NONLM;
980                         break;
981                 case Opt_nolock:
982                         mnt->flags |= NFS_MOUNT_NONLM;
983                         break;
984                 case Opt_v2:
985                         mnt->flags &= ~NFS_MOUNT_VER3;
986                         mnt->version = 2;
987                         break;
988                 case Opt_v3:
989                         mnt->flags |= NFS_MOUNT_VER3;
990                         mnt->version = 3;
991                         break;
992 #ifdef CONFIG_NFS_V4
993                 case Opt_v4:
994                         mnt->flags &= ~NFS_MOUNT_VER3;
995                         mnt->version = 4;
996                         break;
997 #endif
998                 case Opt_udp:
999                         mnt->flags &= ~NFS_MOUNT_TCP;
1000                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1001                         break;
1002                 case Opt_tcp:
1003                         mnt->flags |= NFS_MOUNT_TCP;
1004                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1005                         break;
1006                 case Opt_rdma:
1007                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1008                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1009                         xprt_load_transport(p);
1010                         break;
1011                 case Opt_acl:
1012                         mnt->flags &= ~NFS_MOUNT_NOACL;
1013                         break;
1014                 case Opt_noacl:
1015                         mnt->flags |= NFS_MOUNT_NOACL;
1016                         break;
1017                 case Opt_rdirplus:
1018                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1019                         break;
1020                 case Opt_nordirplus:
1021                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1022                         break;
1023                 case Opt_sharecache:
1024                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1025                         break;
1026                 case Opt_nosharecache:
1027                         mnt->flags |= NFS_MOUNT_UNSHARED;
1028                         break;
1029                 case Opt_resvport:
1030                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1031                         break;
1032                 case Opt_noresvport:
1033                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1034                         break;
1035                 case Opt_fscache:
1036                         mnt->options |= NFS_OPTION_FSCACHE;
1037                         kfree(mnt->fscache_uniq);
1038                         mnt->fscache_uniq = NULL;
1039                         break;
1040                 case Opt_nofscache:
1041                         mnt->options &= ~NFS_OPTION_FSCACHE;
1042                         kfree(mnt->fscache_uniq);
1043                         mnt->fscache_uniq = NULL;
1044                         break;
1045                 case Opt_fscache_uniq:
1046                         string = match_strdup(args);
1047                         if (!string)
1048                                 goto out_nomem;
1049                         kfree(mnt->fscache_uniq);
1050                         mnt->fscache_uniq = string;
1051                         mnt->options |= NFS_OPTION_FSCACHE;
1052                         break;
1053
1054                 /*
1055                  * options that take numeric values
1056                  */
1057                 case Opt_port:
1058                         string = match_strdup(args);
1059                         if (string == NULL)
1060                                 goto out_nomem;
1061                         rc = strict_strtoul(string, 10, &option);
1062                         kfree(string);
1063                         if (rc != 0 || option > USHORT_MAX)
1064                                 goto out_invalid_value;
1065                         mnt->nfs_server.port = option;
1066                         break;
1067                 case Opt_rsize:
1068                         string = match_strdup(args);
1069                         if (string == NULL)
1070                                 goto out_nomem;
1071                         rc = strict_strtoul(string, 10, &option);
1072                         kfree(string);
1073                         if (rc != 0)
1074                                 goto out_invalid_value;
1075                         mnt->rsize = option;
1076                         break;
1077                 case Opt_wsize:
1078                         string = match_strdup(args);
1079                         if (string == NULL)
1080                                 goto out_nomem;
1081                         rc = strict_strtoul(string, 10, &option);
1082                         kfree(string);
1083                         if (rc != 0)
1084                                 goto out_invalid_value;
1085                         mnt->wsize = option;
1086                         break;
1087                 case Opt_bsize:
1088                         string = match_strdup(args);
1089                         if (string == NULL)
1090                                 goto out_nomem;
1091                         rc = strict_strtoul(string, 10, &option);
1092                         kfree(string);
1093                         if (rc != 0)
1094                                 goto out_invalid_value;
1095                         mnt->bsize = option;
1096                         break;
1097                 case Opt_timeo:
1098                         string = match_strdup(args);
1099                         if (string == NULL)
1100                                 goto out_nomem;
1101                         rc = strict_strtoul(string, 10, &option);
1102                         kfree(string);
1103                         if (rc != 0 || option == 0)
1104                                 goto out_invalid_value;
1105                         mnt->timeo = option;
1106                         break;
1107                 case Opt_retrans:
1108                         string = match_strdup(args);
1109                         if (string == NULL)
1110                                 goto out_nomem;
1111                         rc = strict_strtoul(string, 10, &option);
1112                         kfree(string);
1113                         if (rc != 0 || option == 0)
1114                                 goto out_invalid_value;
1115                         mnt->retrans = option;
1116                         break;
1117                 case Opt_acregmin:
1118                         string = match_strdup(args);
1119                         if (string == NULL)
1120                                 goto out_nomem;
1121                         rc = strict_strtoul(string, 10, &option);
1122                         kfree(string);
1123                         if (rc != 0)
1124                                 goto out_invalid_value;
1125                         mnt->acregmin = option;
1126                         break;
1127                 case Opt_acregmax:
1128                         string = match_strdup(args);
1129                         if (string == NULL)
1130                                 goto out_nomem;
1131                         rc = strict_strtoul(string, 10, &option);
1132                         kfree(string);
1133                         if (rc != 0)
1134                                 goto out_invalid_value;
1135                         mnt->acregmax = option;
1136                         break;
1137                 case Opt_acdirmin:
1138                         string = match_strdup(args);
1139                         if (string == NULL)
1140                                 goto out_nomem;
1141                         rc = strict_strtoul(string, 10, &option);
1142                         kfree(string);
1143                         if (rc != 0)
1144                                 goto out_invalid_value;
1145                         mnt->acdirmin = option;
1146                         break;
1147                 case Opt_acdirmax:
1148                         string = match_strdup(args);
1149                         if (string == NULL)
1150                                 goto out_nomem;
1151                         rc = strict_strtoul(string, 10, &option);
1152                         kfree(string);
1153                         if (rc != 0)
1154                                 goto out_invalid_value;
1155                         mnt->acdirmax = option;
1156                         break;
1157                 case Opt_actimeo:
1158                         string = match_strdup(args);
1159                         if (string == NULL)
1160                                 goto out_nomem;
1161                         rc = strict_strtoul(string, 10, &option);
1162                         kfree(string);
1163                         if (rc != 0)
1164                                 goto out_invalid_value;
1165                         mnt->acregmin = mnt->acregmax =
1166                         mnt->acdirmin = mnt->acdirmax = option;
1167                         break;
1168                 case Opt_namelen:
1169                         string = match_strdup(args);
1170                         if (string == NULL)
1171                                 goto out_nomem;
1172                         rc = strict_strtoul(string, 10, &option);
1173                         kfree(string);
1174                         if (rc != 0)
1175                                 goto out_invalid_value;
1176                         mnt->namlen = option;
1177                         break;
1178                 case Opt_mountport:
1179                         string = match_strdup(args);
1180                         if (string == NULL)
1181                                 goto out_nomem;
1182                         rc = strict_strtoul(string, 10, &option);
1183                         kfree(string);
1184                         if (rc != 0 || option > USHORT_MAX)
1185                                 goto out_invalid_value;
1186                         mnt->mount_server.port = option;
1187                         break;
1188                 case Opt_mountvers:
1189                         string = match_strdup(args);
1190                         if (string == NULL)
1191                                 goto out_nomem;
1192                         rc = strict_strtoul(string, 10, &option);
1193                         kfree(string);
1194                         if (rc != 0 ||
1195                             option < NFS_MNT_VERSION ||
1196                             option > NFS_MNT3_VERSION)
1197                                 goto out_invalid_value;
1198                         mnt->mount_server.version = option;
1199                         break;
1200                 case Opt_nfsvers:
1201                         string = match_strdup(args);
1202                         if (string == NULL)
1203                                 goto out_nomem;
1204                         rc = strict_strtoul(string, 10, &option);
1205                         kfree(string);
1206                         if (rc != 0)
1207                                 goto out_invalid_value;
1208                         switch (option) {
1209                         case NFS2_VERSION:
1210                                 mnt->flags &= ~NFS_MOUNT_VER3;
1211                                 mnt->version = 2;
1212                                 break;
1213                         case NFS3_VERSION:
1214                                 mnt->flags |= NFS_MOUNT_VER3;
1215                                 mnt->version = 3;
1216                                 break;
1217 #ifdef CONFIG_NFS_V4
1218                         case NFS4_VERSION:
1219                                 mnt->flags &= ~NFS_MOUNT_VER3;
1220                                 mnt->version = 4;
1221                                 break;
1222 #endif
1223                         default:
1224                                 goto out_invalid_value;
1225                         }
1226                         break;
1227                 case Opt_minorversion:
1228                         string = match_strdup(args);
1229                         if (string == NULL)
1230                                 goto out_nomem;
1231                         rc = strict_strtoul(string, 10, &option);
1232                         kfree(string);
1233                         if (rc != 0)
1234                                 goto out_invalid_value;
1235                         if (option > NFS4_MAX_MINOR_VERSION)
1236                                 goto out_invalid_value;
1237                         mnt->minorversion = option;
1238                         break;
1239
1240                 /*
1241                  * options that take text values
1242                  */
1243                 case Opt_sec:
1244                         string = match_strdup(args);
1245                         if (string == NULL)
1246                                 goto out_nomem;
1247                         rc = nfs_parse_security_flavors(string, mnt);
1248                         kfree(string);
1249                         if (!rc) {
1250                                 dfprintk(MOUNT, "NFS:   unrecognized "
1251                                                 "security flavor\n");
1252                                 return 0;
1253                         }
1254                         break;
1255                 case Opt_proto:
1256                         string = match_strdup(args);
1257                         if (string == NULL)
1258                                 goto out_nomem;
1259                         token = match_token(string,
1260                                             nfs_xprt_protocol_tokens, args);
1261
1262                         protofamily = AF_INET;
1263                         switch (token) {
1264                         case Opt_xprt_udp6:
1265                                 protofamily = AF_INET6;
1266                         case Opt_xprt_udp:
1267                                 mnt->flags &= ~NFS_MOUNT_TCP;
1268                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1269                                 kfree(string);
1270                                 break;
1271                         case Opt_xprt_tcp6:
1272                                 protofamily = AF_INET6;
1273                         case Opt_xprt_tcp:
1274                                 mnt->flags |= NFS_MOUNT_TCP;
1275                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1276                                 kfree(string);
1277                                 break;
1278                         case Opt_xprt_rdma:
1279                                 /* vector side protocols to TCP */
1280                                 mnt->flags |= NFS_MOUNT_TCP;
1281                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1282                                 xprt_load_transport(string);
1283                                 kfree(string);
1284                                 break;
1285                         default:
1286                                 dfprintk(MOUNT, "NFS:   unrecognized "
1287                                                 "transport protocol\n");
1288                                 kfree(string);
1289                                 return 0;
1290                         }
1291                         break;
1292                 case Opt_mountproto:
1293                         string = match_strdup(args);
1294                         if (string == NULL)
1295                                 goto out_nomem;
1296                         token = match_token(string,
1297                                             nfs_xprt_protocol_tokens, args);
1298                         kfree(string);
1299
1300                         mountfamily = AF_INET;
1301                         switch (token) {
1302                         case Opt_xprt_udp6:
1303                                 mountfamily = AF_INET6;
1304                         case Opt_xprt_udp:
1305                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1306                                 break;
1307                         case Opt_xprt_tcp6:
1308                                 mountfamily = AF_INET6;
1309                         case Opt_xprt_tcp:
1310                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1311                                 break;
1312                         case Opt_xprt_rdma: /* not used for side protocols */
1313                         default:
1314                                 dfprintk(MOUNT, "NFS:   unrecognized "
1315                                                 "transport protocol\n");
1316                                 return 0;
1317                         }
1318                         break;
1319                 case Opt_addr:
1320                         string = match_strdup(args);
1321                         if (string == NULL)
1322                                 goto out_nomem;
1323                         mnt->nfs_server.addrlen =
1324                                 rpc_pton(string, strlen(string),
1325                                         (struct sockaddr *)
1326                                         &mnt->nfs_server.address,
1327                                         sizeof(mnt->nfs_server.address));
1328                         kfree(string);
1329                         if (mnt->nfs_server.addrlen == 0)
1330                                 goto out_invalid_address;
1331                         break;
1332                 case Opt_clientaddr:
1333                         string = match_strdup(args);
1334                         if (string == NULL)
1335                                 goto out_nomem;
1336                         kfree(mnt->client_address);
1337                         mnt->client_address = string;
1338                         break;
1339                 case Opt_mounthost:
1340                         string = match_strdup(args);
1341                         if (string == NULL)
1342                                 goto out_nomem;
1343                         kfree(mnt->mount_server.hostname);
1344                         mnt->mount_server.hostname = string;
1345                         break;
1346                 case Opt_mountaddr:
1347                         string = match_strdup(args);
1348                         if (string == NULL)
1349                                 goto out_nomem;
1350                         mnt->mount_server.addrlen =
1351                                 rpc_pton(string, strlen(string),
1352                                         (struct sockaddr *)
1353                                         &mnt->mount_server.address,
1354                                         sizeof(mnt->mount_server.address));
1355                         kfree(string);
1356                         if (mnt->mount_server.addrlen == 0)
1357                                 goto out_invalid_address;
1358                         break;
1359                 case Opt_lookupcache:
1360                         string = match_strdup(args);
1361                         if (string == NULL)
1362                                 goto out_nomem;
1363                         token = match_token(string,
1364                                         nfs_lookupcache_tokens, args);
1365                         kfree(string);
1366                         switch (token) {
1367                                 case Opt_lookupcache_all:
1368                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1369                                         break;
1370                                 case Opt_lookupcache_positive:
1371                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1372                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1373                                         break;
1374                                 case Opt_lookupcache_none:
1375                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1376                                         break;
1377                                 default:
1378                                         dfprintk(MOUNT, "NFS:   invalid "
1379                                                         "lookupcache argument\n");
1380                                         return 0;
1381                         };
1382                         break;
1383
1384                 /*
1385                  * Special options
1386                  */
1387                 case Opt_sloppy:
1388                         sloppy = 1;
1389                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1390                         break;
1391                 case Opt_userspace:
1392                 case Opt_deprecated:
1393                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1394                                         "'%s'\n", p);
1395                         break;
1396
1397                 default:
1398                         invalid_option = 1;
1399                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1400                                         "'%s'\n", p);
1401                 }
1402         }
1403
1404         if (!sloppy && invalid_option)
1405                 return 0;
1406
1407         /*
1408          * verify that any proto=/mountproto= options match the address
1409          * familiies in the addr=/mountaddr= options.
1410          */
1411         if (protofamily != AF_UNSPEC &&
1412             protofamily != mnt->nfs_server.address.ss_family)
1413                 goto out_proto_mismatch;
1414
1415         if (mountfamily != AF_UNSPEC) {
1416                 if (mnt->mount_server.addrlen) {
1417                         if (mountfamily != mnt->mount_server.address.ss_family)
1418                                 goto out_mountproto_mismatch;
1419                 } else {
1420                         if (mountfamily != mnt->nfs_server.address.ss_family)
1421                                 goto out_mountproto_mismatch;
1422                 }
1423         }
1424
1425         return 1;
1426
1427 out_mountproto_mismatch:
1428         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1429                          "option\n");
1430         return 0;
1431 out_proto_mismatch:
1432         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1433         return 0;
1434 out_invalid_address:
1435         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1436         return 0;
1437 out_invalid_value:
1438         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1439         return 0;
1440 out_nomem:
1441         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1442         return 0;
1443 out_security_failure:
1444         free_secdata(secdata);
1445         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1446         return 0;
1447 }
1448
1449 /*
1450  * Match the requested auth flavors with the list returned by
1451  * the server.  Returns zero and sets the mount's authentication
1452  * flavor on success; returns -EACCES if server does not support
1453  * the requested flavor.
1454  */
1455 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1456                              struct nfs_mount_request *request)
1457 {
1458         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1459
1460         /*
1461          * Certain releases of Linux's mountd return an empty
1462          * flavor list.  To prevent behavioral regression with
1463          * these servers (ie. rejecting mounts that used to
1464          * succeed), revert to pre-2.6.32 behavior (no checking)
1465          * if the returned flavor list is empty.
1466          */
1467         if (server_authlist_len == 0)
1468                 return 0;
1469
1470         /*
1471          * We avoid sophisticated negotiating here, as there are
1472          * plenty of cases where we can get it wrong, providing
1473          * either too little or too much security.
1474          *
1475          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1476          * flavor listed first.  However, some servers list
1477          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1478          * preferred default, in args->auth_flavors[0] if user
1479          * didn't specify sec= mount option.
1480          */
1481         for (i = 0; i < args->auth_flavor_len; i++)
1482                 for (j = 0; j < server_authlist_len; j++)
1483                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1484                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1485                                         request->auth_flavs[j]);
1486                                 args->auth_flavors[0] = request->auth_flavs[j];
1487                                 return 0;
1488                         }
1489
1490         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1491         nfs_umount(request);
1492         return -EACCES;
1493 }
1494
1495 /*
1496  * Use the remote server's MOUNT service to request the NFS file handle
1497  * corresponding to the provided path.
1498  */
1499 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1500                          struct nfs_fh *root_fh)
1501 {
1502         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1503         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1504         struct nfs_mount_request request = {
1505                 .sap            = (struct sockaddr *)
1506                                                 &args->mount_server.address,
1507                 .dirpath        = args->nfs_server.export_path,
1508                 .protocol       = args->mount_server.protocol,
1509                 .fh             = root_fh,
1510                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1511                 .auth_flav_len  = &server_authlist_len,
1512                 .auth_flavs     = server_authlist,
1513         };
1514         int status;
1515
1516         if (args->mount_server.version == 0) {
1517                 switch (args->version) {
1518                         default:
1519                                 args->mount_server.version = NFS_MNT3_VERSION;
1520                                 break;
1521                         case 2:
1522                                 args->mount_server.version = NFS_MNT_VERSION;
1523                 }
1524         }
1525         request.version = args->mount_server.version;
1526
1527         if (args->mount_server.hostname)
1528                 request.hostname = args->mount_server.hostname;
1529         else
1530                 request.hostname = args->nfs_server.hostname;
1531
1532         /*
1533          * Construct the mount server's address.
1534          */
1535         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1536                 memcpy(request.sap, &args->nfs_server.address,
1537                        args->nfs_server.addrlen);
1538                 args->mount_server.addrlen = args->nfs_server.addrlen;
1539         }
1540         request.salen = args->mount_server.addrlen;
1541         nfs_set_port(request.sap, &args->mount_server.port, 0);
1542
1543         /*
1544          * Now ask the mount server to map our export path
1545          * to a file handle.
1546          */
1547         status = nfs_mount(&request);
1548         if (status != 0) {
1549                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1550                                 request.hostname, status);
1551                 return status;
1552         }
1553
1554         /*
1555          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1556          */
1557         if (args->mount_server.version != NFS_MNT3_VERSION)
1558                 return 0;
1559         return nfs_walk_authlist(args, &request);
1560 }
1561
1562 static int nfs_parse_simple_hostname(const char *dev_name,
1563                                      char **hostname, size_t maxnamlen,
1564                                      char **export_path, size_t maxpathlen)
1565 {
1566         size_t len;
1567         char *colon, *comma;
1568
1569         colon = strchr(dev_name, ':');
1570         if (colon == NULL)
1571                 goto out_bad_devname;
1572
1573         len = colon - dev_name;
1574         if (len > maxnamlen)
1575                 goto out_hostname;
1576
1577         /* N.B. caller will free nfs_server.hostname in all cases */
1578         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1579         if (!*hostname)
1580                 goto out_nomem;
1581
1582         /* kill possible hostname list: not supported */
1583         comma = strchr(*hostname, ',');
1584         if (comma != NULL) {
1585                 if (comma == *hostname)
1586                         goto out_bad_devname;
1587                 *comma = '\0';
1588         }
1589
1590         colon++;
1591         len = strlen(colon);
1592         if (len > maxpathlen)
1593                 goto out_path;
1594         *export_path = kstrndup(colon, len, GFP_KERNEL);
1595         if (!*export_path)
1596                 goto out_nomem;
1597
1598         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1599         return 0;
1600
1601 out_bad_devname:
1602         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1603         return -EINVAL;
1604
1605 out_nomem:
1606         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1607         return -ENOMEM;
1608
1609 out_hostname:
1610         dfprintk(MOUNT, "NFS: server hostname too long\n");
1611         return -ENAMETOOLONG;
1612
1613 out_path:
1614         dfprintk(MOUNT, "NFS: export pathname too long\n");
1615         return -ENAMETOOLONG;
1616 }
1617
1618 /*
1619  * Hostname has square brackets around it because it contains one or
1620  * more colons.  We look for the first closing square bracket, and a
1621  * colon must follow it.
1622  */
1623 static int nfs_parse_protected_hostname(const char *dev_name,
1624                                         char **hostname, size_t maxnamlen,
1625                                         char **export_path, size_t maxpathlen)
1626 {
1627         size_t len;
1628         char *start, *end;
1629
1630         start = (char *)(dev_name + 1);
1631
1632         end = strchr(start, ']');
1633         if (end == NULL)
1634                 goto out_bad_devname;
1635         if (*(end + 1) != ':')
1636                 goto out_bad_devname;
1637
1638         len = end - start;
1639         if (len > maxnamlen)
1640                 goto out_hostname;
1641
1642         /* N.B. caller will free nfs_server.hostname in all cases */
1643         *hostname = kstrndup(start, len, GFP_KERNEL);
1644         if (*hostname == NULL)
1645                 goto out_nomem;
1646
1647         end += 2;
1648         len = strlen(end);
1649         if (len > maxpathlen)
1650                 goto out_path;
1651         *export_path = kstrndup(end, len, GFP_KERNEL);
1652         if (!*export_path)
1653                 goto out_nomem;
1654
1655         return 0;
1656
1657 out_bad_devname:
1658         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1659         return -EINVAL;
1660
1661 out_nomem:
1662         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1663         return -ENOMEM;
1664
1665 out_hostname:
1666         dfprintk(MOUNT, "NFS: server hostname too long\n");
1667         return -ENAMETOOLONG;
1668
1669 out_path:
1670         dfprintk(MOUNT, "NFS: export pathname too long\n");
1671         return -ENAMETOOLONG;
1672 }
1673
1674 /*
1675  * Split "dev_name" into "hostname:export_path".
1676  *
1677  * The leftmost colon demarks the split between the server's hostname
1678  * and the export path.  If the hostname starts with a left square
1679  * bracket, then it may contain colons.
1680  *
1681  * Note: caller frees hostname and export path, even on error.
1682  */
1683 static int nfs_parse_devname(const char *dev_name,
1684                              char **hostname, size_t maxnamlen,
1685                              char **export_path, size_t maxpathlen)
1686 {
1687         if (*dev_name == '[')
1688                 return nfs_parse_protected_hostname(dev_name,
1689                                                     hostname, maxnamlen,
1690                                                     export_path, maxpathlen);
1691
1692         return nfs_parse_simple_hostname(dev_name,
1693                                          hostname, maxnamlen,
1694                                          export_path, maxpathlen);
1695 }
1696
1697 /*
1698  * Validate the NFS2/NFS3 mount data
1699  * - fills in the mount root filehandle
1700  *
1701  * For option strings, user space handles the following behaviors:
1702  *
1703  * + DNS: mapping server host name to IP address ("addr=" option)
1704  *
1705  * + failure mode: how to behave if a mount request can't be handled
1706  *   immediately ("fg/bg" option)
1707  *
1708  * + retry: how often to retry a mount request ("retry=" option)
1709  *
1710  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1711  *   mountproto=tcp after mountproto=udp, and so on
1712  */
1713 static int nfs_validate_mount_data(void *options,
1714                                    struct nfs_parsed_mount_data *args,
1715                                    struct nfs_fh *mntfh,
1716                                    const char *dev_name)
1717 {
1718         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1719         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1720
1721         if (data == NULL)
1722                 goto out_no_data;
1723
1724         switch (data->version) {
1725         case 1:
1726                 data->namlen = 0;
1727         case 2:
1728                 data->bsize = 0;
1729         case 3:
1730                 if (data->flags & NFS_MOUNT_VER3)
1731                         goto out_no_v3;
1732                 data->root.size = NFS2_FHSIZE;
1733                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1734         case 4:
1735                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1736                         goto out_no_sec;
1737         case 5:
1738                 memset(data->context, 0, sizeof(data->context));
1739         case 6:
1740                 if (data->flags & NFS_MOUNT_VER3) {
1741                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1742                                 goto out_invalid_fh;
1743                         mntfh->size = data->root.size;
1744                         args->version = 3;
1745                 } else {
1746                         mntfh->size = NFS2_FHSIZE;
1747                         args->version = 2;
1748                 }
1749
1750
1751                 memcpy(mntfh->data, data->root.data, mntfh->size);
1752                 if (mntfh->size < sizeof(mntfh->data))
1753                         memset(mntfh->data + mntfh->size, 0,
1754                                sizeof(mntfh->data) - mntfh->size);
1755
1756                 /*
1757                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1758                  * can deal with.
1759                  */
1760                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1761                 args->rsize             = data->rsize;
1762                 args->wsize             = data->wsize;
1763                 args->timeo             = data->timeo;
1764                 args->retrans           = data->retrans;
1765                 args->acregmin          = data->acregmin;
1766                 args->acregmax          = data->acregmax;
1767                 args->acdirmin          = data->acdirmin;
1768                 args->acdirmax          = data->acdirmax;
1769
1770                 memcpy(sap, &data->addr, sizeof(data->addr));
1771                 args->nfs_server.addrlen = sizeof(data->addr);
1772                 if (!nfs_verify_server_address(sap))
1773                         goto out_no_address;
1774
1775                 if (!(data->flags & NFS_MOUNT_TCP))
1776                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1777                 /* N.B. caller will free nfs_server.hostname in all cases */
1778                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1779                 args->namlen            = data->namlen;
1780                 args->bsize             = data->bsize;
1781
1782                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1783                         args->auth_flavors[0] = data->pseudoflavor;
1784                 if (!args->nfs_server.hostname)
1785                         goto out_nomem;
1786
1787                 /*
1788                  * The legacy version 6 binary mount data from userspace has a
1789                  * field used only to transport selinux information into the
1790                  * the kernel.  To continue to support that functionality we
1791                  * have a touch of selinux knowledge here in the NFS code. The
1792                  * userspace code converted context=blah to just blah so we are
1793                  * converting back to the full string selinux understands.
1794                  */
1795                 if (data->context[0]){
1796 #ifdef CONFIG_SECURITY_SELINUX
1797                         int rc;
1798                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1799                         if (!opts_str)
1800                                 return -ENOMEM;
1801                         strcpy(opts_str, "context=");
1802                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1803                         strcat(opts_str, &data->context[0]);
1804                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1805                         kfree(opts_str);
1806                         if (rc)
1807                                 return rc;
1808 #else
1809                         return -EINVAL;
1810 #endif
1811                 }
1812
1813                 break;
1814         default: {
1815                 int status;
1816
1817                 if (nfs_parse_mount_options((char *)options, args) == 0)
1818                         return -EINVAL;
1819
1820                 if (!nfs_verify_server_address(sap))
1821                         goto out_no_address;
1822
1823                 if (args->version == 4)
1824 #ifdef CONFIG_NFS_V4
1825                         return nfs4_validate_text_mount_data(options,
1826                                                              args, dev_name);
1827 #else
1828                         goto out_v4_not_compiled;
1829 #endif
1830
1831                 nfs_set_port(sap, &args->nfs_server.port, 0);
1832
1833                 nfs_set_mount_transport_protocol(args);
1834
1835                 status = nfs_parse_devname(dev_name,
1836                                            &args->nfs_server.hostname,
1837                                            PAGE_SIZE,
1838                                            &args->nfs_server.export_path,
1839                                            NFS_MAXPATHLEN);
1840                 if (!status)
1841                         status = nfs_try_mount(args, mntfh);
1842
1843                 kfree(args->nfs_server.export_path);
1844                 args->nfs_server.export_path = NULL;
1845
1846                 if (status)
1847                         return status;
1848
1849                 break;
1850                 }
1851         }
1852
1853 #ifndef CONFIG_NFS_V3
1854         if (args->version == 3)
1855                 goto out_v3_not_compiled;
1856 #endif /* !CONFIG_NFS_V3 */
1857
1858         return 0;
1859
1860 out_no_data:
1861         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1862         return -EINVAL;
1863
1864 out_no_v3:
1865         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1866                  data->version);
1867         return -EINVAL;
1868
1869 out_no_sec:
1870         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1871         return -EINVAL;
1872
1873 #ifndef CONFIG_NFS_V3
1874 out_v3_not_compiled:
1875         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1876         return -EPROTONOSUPPORT;
1877 #endif /* !CONFIG_NFS_V3 */
1878
1879 #ifndef CONFIG_NFS_V4
1880 out_v4_not_compiled:
1881         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1882         return -EPROTONOSUPPORT;
1883 #endif /* !CONFIG_NFS_V4 */
1884
1885 out_nomem:
1886         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1887         return -ENOMEM;
1888
1889 out_no_address:
1890         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1891         return -EINVAL;
1892
1893 out_invalid_fh:
1894         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1895         return -EINVAL;
1896 }
1897
1898 static int
1899 nfs_compare_remount_data(struct nfs_server *nfss,
1900                          struct nfs_parsed_mount_data *data)
1901 {
1902         if (data->flags != nfss->flags ||
1903             data->rsize != nfss->rsize ||
1904             data->wsize != nfss->wsize ||
1905             data->retrans != nfss->client->cl_timeout->to_retries ||
1906             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1907             data->acregmin != nfss->acregmin / HZ ||
1908             data->acregmax != nfss->acregmax / HZ ||
1909             data->acdirmin != nfss->acdirmin / HZ ||
1910             data->acdirmax != nfss->acdirmax / HZ ||
1911             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1912             data->nfs_server.port != nfss->port ||
1913             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1914             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1915                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1916                 return -EINVAL;
1917
1918         return 0;
1919 }
1920
1921 static int
1922 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1923 {
1924         int error;
1925         struct nfs_server *nfss = sb->s_fs_info;
1926         struct nfs_parsed_mount_data *data;
1927         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1928         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1929         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1930
1931         /*
1932          * Userspace mount programs that send binary options generally send
1933          * them populated with default values. We have no way to know which
1934          * ones were explicitly specified. Fall back to legacy behavior and
1935          * just return success.
1936          */
1937         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1938             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1939                                            options->version <= 6))))
1940                 return 0;
1941
1942         data = kzalloc(sizeof(*data), GFP_KERNEL);
1943         if (data == NULL)
1944                 return -ENOMEM;
1945
1946         /* fill out struct with values from existing mount */
1947         data->flags = nfss->flags;
1948         data->rsize = nfss->rsize;
1949         data->wsize = nfss->wsize;
1950         data->retrans = nfss->client->cl_timeout->to_retries;
1951         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1952         data->acregmin = nfss->acregmin / HZ;
1953         data->acregmax = nfss->acregmax / HZ;
1954         data->acdirmin = nfss->acdirmin / HZ;
1955         data->acdirmax = nfss->acdirmax / HZ;
1956         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1957         data->nfs_server.port = nfss->port;
1958         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1959         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1960                 data->nfs_server.addrlen);
1961
1962         /* overwrite those values with any that were specified */
1963         error = nfs_parse_mount_options((char *)options, data);
1964         if (error < 0)
1965                 goto out;
1966
1967         /* compare new mount options with old ones */
1968         error = nfs_compare_remount_data(nfss, data);
1969 out:
1970         kfree(data);
1971         return error;
1972 }
1973
1974 /*
1975  * Initialise the common bits of the superblock
1976  */
1977 static inline void nfs_initialise_sb(struct super_block *sb)
1978 {
1979         struct nfs_server *server = NFS_SB(sb);
1980
1981         sb->s_magic = NFS_SUPER_MAGIC;
1982
1983         /* We probably want something more informative here */
1984         snprintf(sb->s_id, sizeof(sb->s_id),
1985                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1986
1987         if (sb->s_blocksize == 0)
1988                 sb->s_blocksize = nfs_block_bits(server->wsize,
1989                                                  &sb->s_blocksize_bits);
1990
1991         if (server->flags & NFS_MOUNT_NOAC)
1992                 sb->s_flags |= MS_SYNCHRONOUS;
1993
1994         sb->s_bdi = &server->backing_dev_info;
1995
1996         nfs_super_set_maxbytes(sb, server->maxfilesize);
1997 }
1998
1999 /*
2000  * Finish setting up an NFS2/3 superblock
2001  */
2002 static void nfs_fill_super(struct super_block *sb,
2003                            struct nfs_parsed_mount_data *data)
2004 {
2005         struct nfs_server *server = NFS_SB(sb);
2006
2007         sb->s_blocksize_bits = 0;
2008         sb->s_blocksize = 0;
2009         if (data->bsize)
2010                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2011
2012         if (server->nfs_client->rpc_ops->version == 3) {
2013                 /* The VFS shouldn't apply the umask to mode bits. We will do
2014                  * so ourselves when necessary.
2015                  */
2016                 sb->s_flags |= MS_POSIXACL;
2017                 sb->s_time_gran = 1;
2018         }
2019
2020         sb->s_op = &nfs_sops;
2021         nfs_initialise_sb(sb);
2022 }
2023
2024 /*
2025  * Finish setting up a cloned NFS2/3 superblock
2026  */
2027 static void nfs_clone_super(struct super_block *sb,
2028                             const struct super_block *old_sb)
2029 {
2030         struct nfs_server *server = NFS_SB(sb);
2031
2032         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2033         sb->s_blocksize = old_sb->s_blocksize;
2034         sb->s_maxbytes = old_sb->s_maxbytes;
2035
2036         if (server->nfs_client->rpc_ops->version == 3) {
2037                 /* The VFS shouldn't apply the umask to mode bits. We will do
2038                  * so ourselves when necessary.
2039                  */
2040                 sb->s_flags |= MS_POSIXACL;
2041                 sb->s_time_gran = 1;
2042         }
2043
2044         sb->s_op = old_sb->s_op;
2045         nfs_initialise_sb(sb);
2046 }
2047
2048 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2049 {
2050         const struct nfs_server *a = s->s_fs_info;
2051         const struct rpc_clnt *clnt_a = a->client;
2052         const struct rpc_clnt *clnt_b = b->client;
2053
2054         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2055                 goto Ebusy;
2056         if (a->nfs_client != b->nfs_client)
2057                 goto Ebusy;
2058         if (a->flags != b->flags)
2059                 goto Ebusy;
2060         if (a->wsize != b->wsize)
2061                 goto Ebusy;
2062         if (a->rsize != b->rsize)
2063                 goto Ebusy;
2064         if (a->acregmin != b->acregmin)
2065                 goto Ebusy;
2066         if (a->acregmax != b->acregmax)
2067                 goto Ebusy;
2068         if (a->acdirmin != b->acdirmin)
2069                 goto Ebusy;
2070         if (a->acdirmax != b->acdirmax)
2071                 goto Ebusy;
2072         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2073                 goto Ebusy;
2074         return 1;
2075 Ebusy:
2076         return 0;
2077 }
2078
2079 struct nfs_sb_mountdata {
2080         struct nfs_server *server;
2081         int mntflags;
2082 };
2083
2084 static int nfs_set_super(struct super_block *s, void *data)
2085 {
2086         struct nfs_sb_mountdata *sb_mntdata = data;
2087         struct nfs_server *server = sb_mntdata->server;
2088         int ret;
2089
2090         s->s_flags = sb_mntdata->mntflags;
2091         s->s_fs_info = server;
2092         ret = set_anon_super(s, server);
2093         if (ret == 0)
2094                 server->s_dev = s->s_dev;
2095         return ret;
2096 }
2097
2098 static int nfs_compare_super_address(struct nfs_server *server1,
2099                                      struct nfs_server *server2)
2100 {
2101         struct sockaddr *sap1, *sap2;
2102
2103         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2104         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2105
2106         if (sap1->sa_family != sap2->sa_family)
2107                 return 0;
2108
2109         switch (sap1->sa_family) {
2110         case AF_INET: {
2111                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2112                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2113                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2114                         return 0;
2115                 if (sin1->sin_port != sin2->sin_port)
2116                         return 0;
2117                 break;
2118         }
2119         case AF_INET6: {
2120                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2121                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2122                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2123                         return 0;
2124                 if (sin1->sin6_port != sin2->sin6_port)
2125                         return 0;
2126                 break;
2127         }
2128         default:
2129                 return 0;
2130         }
2131
2132         return 1;
2133 }
2134
2135 static int nfs_compare_super(struct super_block *sb, void *data)
2136 {
2137         struct nfs_sb_mountdata *sb_mntdata = data;
2138         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2139         int mntflags = sb_mntdata->mntflags;
2140
2141         if (!nfs_compare_super_address(old, server))
2142                 return 0;
2143         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2144         if (old->flags & NFS_MOUNT_UNSHARED)
2145                 return 0;
2146         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2147                 return 0;
2148         return nfs_compare_mount_options(sb, server, mntflags);
2149 }
2150
2151 static int nfs_bdi_register(struct nfs_server *server)
2152 {
2153         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2154 }
2155
2156 static int nfs_get_sb(struct file_system_type *fs_type,
2157         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2158 {
2159         struct nfs_server *server = NULL;
2160         struct super_block *s;
2161         struct nfs_parsed_mount_data *data;
2162         struct nfs_fh *mntfh;
2163         struct dentry *mntroot;
2164         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2165         struct nfs_sb_mountdata sb_mntdata = {
2166                 .mntflags = flags,
2167         };
2168         int error = -ENOMEM;
2169
2170         data = nfs_alloc_parsed_mount_data(3);
2171         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2172         if (data == NULL || mntfh == NULL)
2173                 goto out_free_fh;
2174
2175         security_init_mnt_opts(&data->lsm_opts);
2176
2177         /* Validate the mount data */
2178         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2179         if (error < 0)
2180                 goto out;
2181
2182 #ifdef CONFIG_NFS_V4
2183         if (data->version == 4) {
2184                 error = nfs4_try_mount(flags, dev_name, data, mnt);
2185                 kfree(data->client_address);
2186                 goto out;
2187         }
2188 #endif  /* CONFIG_NFS_V4 */
2189
2190         /* Get a volume representation */
2191         server = nfs_create_server(data, mntfh);
2192         if (IS_ERR(server)) {
2193                 error = PTR_ERR(server);
2194                 goto out;
2195         }
2196         sb_mntdata.server = server;
2197
2198         if (server->flags & NFS_MOUNT_UNSHARED)
2199                 compare_super = NULL;
2200
2201         /* Get a superblock - note that we may end up sharing one that already exists */
2202         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2203         if (IS_ERR(s)) {
2204                 error = PTR_ERR(s);
2205                 goto out_err_nosb;
2206         }
2207
2208         if (s->s_fs_info != server) {
2209                 nfs_free_server(server);
2210                 server = NULL;
2211         } else {
2212                 error = nfs_bdi_register(server);
2213                 if (error)
2214                         goto error_splat_super;
2215         }
2216
2217         if (!s->s_root) {
2218                 /* initial superblock/root creation */
2219                 nfs_fill_super(s, data);
2220                 nfs_fscache_get_super_cookie(
2221                         s, data ? data->fscache_uniq : NULL, NULL);
2222         }
2223
2224         mntroot = nfs_get_root(s, mntfh);
2225         if (IS_ERR(mntroot)) {
2226                 error = PTR_ERR(mntroot);
2227                 goto error_splat_super;
2228         }
2229
2230         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2231         if (error)
2232                 goto error_splat_root;
2233
2234         s->s_flags |= MS_ACTIVE;
2235         mnt->mnt_sb = s;
2236         mnt->mnt_root = mntroot;
2237         error = 0;
2238
2239 out:
2240         kfree(data->nfs_server.hostname);
2241         kfree(data->mount_server.hostname);
2242         kfree(data->fscache_uniq);
2243         security_free_mnt_opts(&data->lsm_opts);
2244 out_free_fh:
2245         kfree(mntfh);
2246         kfree(data);
2247         return error;
2248
2249 out_err_nosb:
2250         nfs_free_server(server);
2251         goto out;
2252
2253 error_splat_root:
2254         dput(mntroot);
2255 error_splat_super:
2256         deactivate_locked_super(s);
2257         goto out;
2258 }
2259
2260 /*
2261  * Destroy an NFS2/3 superblock
2262  */
2263 static void nfs_kill_super(struct super_block *s)
2264 {
2265         struct nfs_server *server = NFS_SB(s);
2266
2267         kill_anon_super(s);
2268         bdi_unregister(&server->backing_dev_info);
2269         nfs_fscache_release_super_cookie(s);
2270         nfs_free_server(server);
2271 }
2272
2273 /*
2274  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2275  */
2276 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
2277                            const char *dev_name, void *raw_data,
2278                            struct vfsmount *mnt)
2279 {
2280         struct nfs_clone_mount *data = raw_data;
2281         struct super_block *s;
2282         struct nfs_server *server;
2283         struct dentry *mntroot;
2284         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2285         struct nfs_sb_mountdata sb_mntdata = {
2286                 .mntflags = flags,
2287         };
2288         int error;
2289
2290         dprintk("--> nfs_xdev_get_sb()\n");
2291
2292         /* create a new volume representation */
2293         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2294         if (IS_ERR(server)) {
2295                 error = PTR_ERR(server);
2296                 goto out_err_noserver;
2297         }
2298         sb_mntdata.server = server;
2299
2300         if (server->flags & NFS_MOUNT_UNSHARED)
2301                 compare_super = NULL;
2302
2303         /* Get a superblock - note that we may end up sharing one that already exists */
2304         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2305         if (IS_ERR(s)) {
2306                 error = PTR_ERR(s);
2307                 goto out_err_nosb;
2308         }
2309
2310         if (s->s_fs_info != server) {
2311                 nfs_free_server(server);
2312                 server = NULL;
2313         } else {
2314                 error = nfs_bdi_register(server);
2315                 if (error)
2316                         goto error_splat_super;
2317         }
2318
2319         if (!s->s_root) {
2320                 /* initial superblock/root creation */
2321                 nfs_clone_super(s, data->sb);
2322                 nfs_fscache_get_super_cookie(s, NULL, data);
2323         }
2324
2325         mntroot = nfs_get_root(s, data->fh);
2326         if (IS_ERR(mntroot)) {
2327                 error = PTR_ERR(mntroot);
2328                 goto error_splat_super;
2329         }
2330         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2331                 dput(mntroot);
2332                 error = -ESTALE;
2333                 goto error_splat_super;
2334         }
2335
2336         s->s_flags |= MS_ACTIVE;
2337         mnt->mnt_sb = s;
2338         mnt->mnt_root = mntroot;
2339
2340         /* clone any lsm security options from the parent to the new sb */
2341         security_sb_clone_mnt_opts(data->sb, s);
2342
2343         dprintk("<-- nfs_xdev_get_sb() = 0\n");
2344         return 0;
2345
2346 out_err_nosb:
2347         nfs_free_server(server);
2348 out_err_noserver:
2349         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
2350         return error;
2351
2352 error_splat_super:
2353         deactivate_locked_super(s);
2354         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
2355         return error;
2356 }
2357
2358 #ifdef CONFIG_NFS_V4
2359
2360 /*
2361  * Finish setting up a cloned NFS4 superblock
2362  */
2363 static void nfs4_clone_super(struct super_block *sb,
2364                             const struct super_block *old_sb)
2365 {
2366         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2367         sb->s_blocksize = old_sb->s_blocksize;
2368         sb->s_maxbytes = old_sb->s_maxbytes;
2369         sb->s_time_gran = 1;
2370         sb->s_op = old_sb->s_op;
2371         nfs_initialise_sb(sb);
2372 }
2373
2374 /*
2375  * Set up an NFS4 superblock
2376  */
2377 static void nfs4_fill_super(struct super_block *sb)
2378 {
2379         sb->s_time_gran = 1;
2380         sb->s_op = &nfs4_sops;
2381         nfs_initialise_sb(sb);
2382 }
2383
2384 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2385 {
2386         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3);
2387 }
2388
2389 static int nfs4_validate_text_mount_data(void *options,
2390                                          struct nfs_parsed_mount_data *args,
2391                                          const char *dev_name)
2392 {
2393         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2394
2395         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2396
2397         nfs_validate_transport_protocol(args);
2398
2399         nfs4_validate_mount_flags(args);
2400
2401         if (args->version != 4) {
2402                 dfprintk(MOUNT,
2403                          "NFS4: Illegal mount version\n");
2404                 return -EINVAL;
2405         }
2406
2407         if (args->auth_flavor_len > 1) {
2408                 dfprintk(MOUNT,
2409                          "NFS4: Too many RPC auth flavours specified\n");
2410                 return -EINVAL;
2411         }
2412
2413         if (args->client_address == NULL) {
2414                 dfprintk(MOUNT,
2415                          "NFS4: mount program didn't pass callback address\n");
2416                 return -EINVAL;
2417         }
2418
2419         return nfs_parse_devname(dev_name,
2420                                    &args->nfs_server.hostname,
2421                                    NFS4_MAXNAMLEN,
2422                                    &args->nfs_server.export_path,
2423                                    NFS4_MAXPATHLEN);
2424 }
2425
2426 /*
2427  * Validate NFSv4 mount options
2428  */
2429 static int nfs4_validate_mount_data(void *options,
2430                                     struct nfs_parsed_mount_data *args,
2431                                     const char *dev_name)
2432 {
2433         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2434         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2435         char *c;
2436
2437         if (data == NULL)
2438                 goto out_no_data;
2439
2440         switch (data->version) {
2441         case 1:
2442                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2443                         goto out_no_address;
2444                 if (data->host_addrlen == 0)
2445                         goto out_no_address;
2446                 args->nfs_server.addrlen = data->host_addrlen;
2447                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2448                         return -EFAULT;
2449                 if (!nfs_verify_server_address(sap))
2450                         goto out_no_address;
2451
2452                 if (data->auth_flavourlen) {
2453                         if (data->auth_flavourlen > 1)
2454                                 goto out_inval_auth;
2455                         if (copy_from_user(&args->auth_flavors[0],
2456                                            data->auth_flavours,
2457                                            sizeof(args->auth_flavors[0])))
2458                                 return -EFAULT;
2459                 }
2460
2461                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2462                 if (IS_ERR(c))
2463                         return PTR_ERR(c);
2464                 args->nfs_server.hostname = c;
2465
2466                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2467                 if (IS_ERR(c))
2468                         return PTR_ERR(c);
2469                 args->nfs_server.export_path = c;
2470                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2471
2472                 c = strndup_user(data->client_addr.data, 16);
2473                 if (IS_ERR(c))
2474                         return PTR_ERR(c);
2475                 args->client_address = c;
2476
2477                 /*
2478                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2479                  * can deal with.
2480                  */
2481
2482                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2483                 args->rsize     = data->rsize;
2484                 args->wsize     = data->wsize;
2485                 args->timeo     = data->timeo;
2486                 args->retrans   = data->retrans;
2487                 args->acregmin  = data->acregmin;
2488                 args->acregmax  = data->acregmax;
2489                 args->acdirmin  = data->acdirmin;
2490                 args->acdirmax  = data->acdirmax;
2491                 args->nfs_server.protocol = data->proto;
2492                 nfs_validate_transport_protocol(args);
2493
2494                 break;
2495         default:
2496                 if (nfs_parse_mount_options((char *)options, args) == 0)
2497                         return -EINVAL;
2498
2499                 if (!nfs_verify_server_address(sap))
2500                         return -EINVAL;
2501
2502                 return nfs4_validate_text_mount_data(options, args, dev_name);
2503         }
2504
2505         return 0;
2506
2507 out_no_data:
2508         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2509         return -EINVAL;
2510
2511 out_inval_auth:
2512         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2513                  data->auth_flavourlen);
2514         return -EINVAL;
2515
2516 out_no_address:
2517         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2518         return -EINVAL;
2519 }
2520
2521 /*
2522  * Get the superblock for the NFS4 root partition
2523  */
2524 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
2525         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2526 {
2527         struct nfs_parsed_mount_data *data = raw_data;
2528         struct super_block *s;
2529         struct nfs_server *server;
2530         struct nfs_fh *mntfh;
2531         struct dentry *mntroot;
2532         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2533         struct nfs_sb_mountdata sb_mntdata = {
2534                 .mntflags = flags,
2535         };
2536         int error = -ENOMEM;
2537
2538         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2539         if (data == NULL || mntfh == NULL)
2540                 goto out_free_fh;
2541
2542         security_init_mnt_opts(&data->lsm_opts);
2543
2544         /* Get a volume representation */
2545         server = nfs4_create_server(data, mntfh);
2546         if (IS_ERR(server)) {
2547                 error = PTR_ERR(server);
2548                 goto out;
2549         }
2550         sb_mntdata.server = server;
2551
2552         if (server->flags & NFS4_MOUNT_UNSHARED)
2553                 compare_super = NULL;
2554
2555         /* Get a superblock - note that we may end up sharing one that already exists */
2556         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2557         if (IS_ERR(s)) {
2558                 error = PTR_ERR(s);
2559                 goto out_free;
2560         }
2561
2562         if (s->s_fs_info != server) {
2563                 nfs_free_server(server);
2564                 server = NULL;
2565         } else {
2566                 error = nfs_bdi_register(server);
2567                 if (error)
2568                         goto error_splat_super;
2569         }
2570
2571         if (!s->s_root) {
2572                 /* initial superblock/root creation */
2573                 nfs4_fill_super(s);
2574                 nfs_fscache_get_super_cookie(
2575                         s, data ? data->fscache_uniq : NULL, NULL);
2576         }
2577
2578         mntroot = nfs4_get_root(s, mntfh);
2579         if (IS_ERR(mntroot)) {
2580                 error = PTR_ERR(mntroot);
2581                 goto error_splat_super;
2582         }
2583
2584         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2585         if (error)
2586                 goto error_splat_root;
2587
2588         s->s_flags |= MS_ACTIVE;
2589         mnt->mnt_sb = s;
2590         mnt->mnt_root = mntroot;
2591         error = 0;
2592
2593 out:
2594         security_free_mnt_opts(&data->lsm_opts);
2595 out_free_fh:
2596         kfree(mntfh);
2597         return error;
2598
2599 out_free:
2600         nfs_free_server(server);
2601         goto out;
2602
2603 error_splat_root:
2604         dput(mntroot);
2605 error_splat_super:
2606         deactivate_locked_super(s);
2607         goto out;
2608 }
2609
2610 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2611                 int flags, void *data, const char *hostname)
2612 {
2613         struct vfsmount *root_mnt;
2614         char *root_devname;
2615         size_t len;
2616
2617         len = strlen(hostname) + 3;
2618         root_devname = kmalloc(len, GFP_KERNEL);
2619         if (root_devname == NULL)
2620                 return ERR_PTR(-ENOMEM);
2621         snprintf(root_devname, len, "%s:/", hostname);
2622         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2623         kfree(root_devname);
2624         return root_mnt;
2625 }
2626
2627 static void nfs_fix_devname(const struct path *path, struct vfsmount *mnt)
2628 {
2629         char *page = (char *) __get_free_page(GFP_KERNEL);
2630         char *devname, *tmp;
2631
2632         if (page == NULL)
2633                 return;
2634         devname = nfs_path(path->mnt->mnt_devname,
2635                         path->mnt->mnt_root, path->dentry,
2636                         page, PAGE_SIZE);
2637         if (devname == NULL)
2638                 goto out_freepage;
2639         tmp = kstrdup(devname, GFP_KERNEL);
2640         if (tmp == NULL)
2641                 goto out_freepage;
2642         kfree(mnt->mnt_devname);
2643         mnt->mnt_devname = tmp;
2644 out_freepage:
2645         free_page((unsigned long)page);
2646 }
2647
2648 static int nfs_follow_remote_path(struct vfsmount *root_mnt,
2649                 const char *export_path, struct vfsmount *mnt_target)
2650 {
2651         struct mnt_namespace *ns_private;
2652         struct nameidata nd;
2653         struct super_block *s;
2654         int ret;
2655
2656         ns_private = create_mnt_ns(root_mnt);
2657         ret = PTR_ERR(ns_private);
2658         if (IS_ERR(ns_private))
2659                 goto out_mntput;
2660
2661         ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
2662                         export_path, LOOKUP_FOLLOW, &nd);
2663
2664         put_mnt_ns(ns_private);
2665
2666         if (ret != 0)
2667                 goto out_err;
2668
2669         s = nd.path.mnt->mnt_sb;
2670         atomic_inc(&s->s_active);
2671         mnt_target->mnt_sb = s;
2672         mnt_target->mnt_root = dget(nd.path.dentry);
2673
2674         /* Correct the device pathname */
2675         nfs_fix_devname(&nd.path, mnt_target);
2676
2677         path_put(&nd.path);
2678         down_write(&s->s_umount);
2679         return 0;
2680 out_mntput:
2681         mntput(root_mnt);
2682 out_err:
2683         return ret;
2684 }
2685
2686 static int nfs4_try_mount(int flags, const char *dev_name,
2687                          struct nfs_parsed_mount_data *data,
2688                          struct vfsmount *mnt)
2689 {
2690         char *export_path;
2691         struct vfsmount *root_mnt;
2692         int error;
2693
2694         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2695
2696         export_path = data->nfs_server.export_path;
2697         data->nfs_server.export_path = "/";
2698         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2699                         data->nfs_server.hostname);
2700         data->nfs_server.export_path = export_path;
2701
2702         error = PTR_ERR(root_mnt);
2703         if (IS_ERR(root_mnt))
2704                 goto out;
2705
2706         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
2707
2708 out:
2709         dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n", error,
2710                         error != 0 ? " [error]" : "");
2711         return error;
2712 }
2713
2714 /*
2715  * Get the superblock for an NFS4 mountpoint
2716  */
2717 static int nfs4_get_sb(struct file_system_type *fs_type,
2718         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2719 {
2720         struct nfs_parsed_mount_data *data;
2721         int error = -ENOMEM;
2722
2723         data = nfs_alloc_parsed_mount_data(4);
2724         if (data == NULL)
2725                 goto out_free_data;
2726
2727         /* Validate the mount data */
2728         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2729         if (error < 0)
2730                 goto out;
2731
2732         error = nfs4_try_mount(flags, dev_name, data, mnt);
2733
2734 out:
2735         kfree(data->client_address);
2736         kfree(data->nfs_server.export_path);
2737         kfree(data->nfs_server.hostname);
2738         kfree(data->fscache_uniq);
2739 out_free_data:
2740         kfree(data);
2741         dprintk("<-- nfs4_get_sb() = %d%s\n", error,
2742                         error != 0 ? " [error]" : "");
2743         return error;
2744 }
2745
2746 static void nfs4_kill_super(struct super_block *sb)
2747 {
2748         struct nfs_server *server = NFS_SB(sb);
2749
2750         dprintk("--> %s\n", __func__);
2751         nfs_super_return_all_delegations(sb);
2752         kill_anon_super(sb);
2753         nfs_fscache_release_super_cookie(sb);
2754         nfs_free_server(server);
2755         dprintk("<-- %s\n", __func__);
2756 }
2757
2758 /*
2759  * Clone an NFS4 server record on xdev traversal (FSID-change)
2760  */
2761 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2762                             const char *dev_name, void *raw_data,
2763                             struct vfsmount *mnt)
2764 {
2765         struct nfs_clone_mount *data = raw_data;
2766         struct super_block *s;
2767         struct nfs_server *server;
2768         struct dentry *mntroot;
2769         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2770         struct nfs_sb_mountdata sb_mntdata = {
2771                 .mntflags = flags,
2772         };
2773         int error;
2774
2775         dprintk("--> nfs4_xdev_get_sb()\n");
2776
2777         /* create a new volume representation */
2778         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2779         if (IS_ERR(server)) {
2780                 error = PTR_ERR(server);
2781                 goto out_err_noserver;
2782         }
2783         sb_mntdata.server = server;
2784
2785         if (server->flags & NFS4_MOUNT_UNSHARED)
2786                 compare_super = NULL;
2787
2788         /* Get a superblock - note that we may end up sharing one that already exists */
2789         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2790         if (IS_ERR(s)) {
2791                 error = PTR_ERR(s);
2792                 goto out_err_nosb;
2793         }
2794
2795         if (s->s_fs_info != server) {
2796                 nfs_free_server(server);
2797                 server = NULL;
2798         } else {
2799                 error = nfs_bdi_register(server);
2800                 if (error)
2801                         goto error_splat_super;
2802         }
2803
2804         if (!s->s_root) {
2805                 /* initial superblock/root creation */
2806                 nfs4_clone_super(s, data->sb);
2807                 nfs_fscache_get_super_cookie(s, NULL, data);
2808         }
2809
2810         mntroot = nfs4_get_root(s, data->fh);
2811         if (IS_ERR(mntroot)) {
2812                 error = PTR_ERR(mntroot);
2813                 goto error_splat_super;
2814         }
2815         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2816                 dput(mntroot);
2817                 error = -ESTALE;
2818                 goto error_splat_super;
2819         }
2820
2821         s->s_flags |= MS_ACTIVE;
2822         mnt->mnt_sb = s;
2823         mnt->mnt_root = mntroot;
2824
2825         security_sb_clone_mnt_opts(data->sb, s);
2826
2827         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2828         return 0;
2829
2830 out_err_nosb:
2831         nfs_free_server(server);
2832 out_err_noserver:
2833         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2834         return error;
2835
2836 error_splat_super:
2837         deactivate_locked_super(s);
2838         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2839         return error;
2840 }
2841
2842 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
2843                 int flags, const char *dev_name, void *raw_data,
2844                 struct vfsmount *mnt)
2845 {
2846         struct nfs_clone_mount *data = raw_data;
2847         struct super_block *s;
2848         struct nfs_server *server;
2849         struct dentry *mntroot;
2850         struct nfs_fh mntfh;
2851         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2852         struct nfs_sb_mountdata sb_mntdata = {
2853                 .mntflags = flags,
2854         };
2855         int error;
2856
2857         dprintk("--> nfs4_referral_get_sb()\n");
2858
2859         /* create a new volume representation */
2860         server = nfs4_create_referral_server(data, &mntfh);
2861         if (IS_ERR(server)) {
2862                 error = PTR_ERR(server);
2863                 goto out_err_noserver;
2864         }
2865         sb_mntdata.server = server;
2866
2867         if (server->flags & NFS4_MOUNT_UNSHARED)
2868                 compare_super = NULL;
2869
2870         /* Get a superblock - note that we may end up sharing one that already exists */
2871         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2872         if (IS_ERR(s)) {
2873                 error = PTR_ERR(s);
2874                 goto out_err_nosb;
2875         }
2876
2877         if (s->s_fs_info != server) {
2878                 nfs_free_server(server);
2879                 server = NULL;
2880         } else {
2881                 error = nfs_bdi_register(server);
2882                 if (error)
2883                         goto error_splat_super;
2884         }
2885
2886         if (!s->s_root) {
2887                 /* initial superblock/root creation */
2888                 nfs4_fill_super(s);
2889                 nfs_fscache_get_super_cookie(s, NULL, data);
2890         }
2891
2892         mntroot = nfs4_get_root(s, &mntfh);
2893         if (IS_ERR(mntroot)) {
2894                 error = PTR_ERR(mntroot);
2895                 goto error_splat_super;
2896         }
2897         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2898                 dput(mntroot);
2899                 error = -ESTALE;
2900                 goto error_splat_super;
2901         }
2902
2903         s->s_flags |= MS_ACTIVE;
2904         mnt->mnt_sb = s;
2905         mnt->mnt_root = mntroot;
2906
2907         security_sb_clone_mnt_opts(data->sb, s);
2908
2909         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2910         return 0;
2911
2912 out_err_nosb:
2913         nfs_free_server(server);
2914 out_err_noserver:
2915         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2916         return error;
2917
2918 error_splat_super:
2919         deactivate_locked_super(s);
2920         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2921         return error;
2922 }
2923
2924 /*
2925  * Create an NFS4 server record on referral traversal
2926  */
2927 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
2928                 int flags, const char *dev_name, void *raw_data,
2929                 struct vfsmount *mnt)
2930 {
2931         struct nfs_clone_mount *data = raw_data;
2932         char *export_path;
2933         struct vfsmount *root_mnt;
2934         int error;
2935
2936         dprintk("--> nfs4_referral_get_sb()\n");
2937
2938         export_path = data->mnt_path;
2939         data->mnt_path = "/";
2940
2941         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
2942                         flags, data, data->hostname);
2943         data->mnt_path = export_path;
2944
2945         error = PTR_ERR(root_mnt);
2946         if (IS_ERR(root_mnt))
2947                 goto out;
2948
2949         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
2950 out:
2951         dprintk("<-- nfs4_referral_get_sb() = %d%s\n", error,
2952                         error != 0 ? " [error]" : "");
2953         return error;
2954 }
2955
2956 #endif /* CONFIG_NFS_V4 */