tcp: fix TCP_MAXSEG for established IPv6 passive sockets
[pandora-kernel.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/seq_file.h>
43 #include <linux/mount.h>
44 #include <linux/mnt_namespace.h>
45 #include <linux/namei.h>
46 #include <linux/nfs_idmap.h>
47 #include <linux/vfs.h>
48 #include <linux/inet.h>
49 #include <linux/in6.h>
50 #include <linux/slab.h>
51 #include <net/ipv6.h>
52 #include <linux/netdevice.h>
53 #include <linux/nfs_xdr.h>
54 #include <linux/magic.h>
55 #include <linux/parser.h>
56
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 #include "pnfs.h"
67
68 #define NFSDBG_FACILITY         NFSDBG_VFS
69
70 #ifdef CONFIG_NFS_V3
71 #define NFS_DEFAULT_VERSION 3
72 #else
73 #define NFS_DEFAULT_VERSION 2
74 #endif
75
76 enum {
77         /* Mount options that take no arguments */
78         Opt_soft, Opt_hard,
79         Opt_posix, Opt_noposix,
80         Opt_cto, Opt_nocto,
81         Opt_ac, Opt_noac,
82         Opt_lock, Opt_nolock,
83         Opt_v2, Opt_v3, Opt_v4,
84         Opt_udp, Opt_tcp, Opt_rdma,
85         Opt_acl, Opt_noacl,
86         Opt_rdirplus, Opt_nordirplus,
87         Opt_sharecache, Opt_nosharecache,
88         Opt_resvport, Opt_noresvport,
89         Opt_fscache, Opt_nofscache,
90
91         /* Mount options that take integer arguments */
92         Opt_port,
93         Opt_rsize, Opt_wsize, Opt_bsize,
94         Opt_timeo, Opt_retrans,
95         Opt_acregmin, Opt_acregmax,
96         Opt_acdirmin, Opt_acdirmax,
97         Opt_actimeo,
98         Opt_namelen,
99         Opt_mountport,
100         Opt_mountvers,
101         Opt_nfsvers,
102         Opt_minorversion,
103
104         /* Mount options that take string arguments */
105         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
106         Opt_addr, Opt_mountaddr, Opt_clientaddr,
107         Opt_lookupcache,
108         Opt_fscache_uniq,
109         Opt_local_lock,
110
111         /* Special mount options */
112         Opt_userspace, Opt_deprecated, Opt_sloppy,
113
114         Opt_err
115 };
116
117 static const match_table_t nfs_mount_option_tokens = {
118         { Opt_userspace, "bg" },
119         { Opt_userspace, "fg" },
120         { Opt_userspace, "retry=%s" },
121
122         { Opt_sloppy, "sloppy" },
123
124         { Opt_soft, "soft" },
125         { Opt_hard, "hard" },
126         { Opt_deprecated, "intr" },
127         { Opt_deprecated, "nointr" },
128         { Opt_posix, "posix" },
129         { Opt_noposix, "noposix" },
130         { Opt_cto, "cto" },
131         { Opt_nocto, "nocto" },
132         { Opt_ac, "ac" },
133         { Opt_noac, "noac" },
134         { Opt_lock, "lock" },
135         { Opt_nolock, "nolock" },
136         { Opt_v2, "v2" },
137         { Opt_v3, "v3" },
138         { Opt_v4, "v4" },
139         { Opt_udp, "udp" },
140         { Opt_tcp, "tcp" },
141         { Opt_rdma, "rdma" },
142         { Opt_acl, "acl" },
143         { Opt_noacl, "noacl" },
144         { Opt_rdirplus, "rdirplus" },
145         { Opt_nordirplus, "nordirplus" },
146         { Opt_sharecache, "sharecache" },
147         { Opt_nosharecache, "nosharecache" },
148         { Opt_resvport, "resvport" },
149         { Opt_noresvport, "noresvport" },
150         { Opt_fscache, "fsc" },
151         { Opt_nofscache, "nofsc" },
152
153         { Opt_port, "port=%s" },
154         { Opt_rsize, "rsize=%s" },
155         { Opt_wsize, "wsize=%s" },
156         { Opt_bsize, "bsize=%s" },
157         { Opt_timeo, "timeo=%s" },
158         { Opt_retrans, "retrans=%s" },
159         { Opt_acregmin, "acregmin=%s" },
160         { Opt_acregmax, "acregmax=%s" },
161         { Opt_acdirmin, "acdirmin=%s" },
162         { Opt_acdirmax, "acdirmax=%s" },
163         { Opt_actimeo, "actimeo=%s" },
164         { Opt_namelen, "namlen=%s" },
165         { Opt_mountport, "mountport=%s" },
166         { Opt_mountvers, "mountvers=%s" },
167         { Opt_nfsvers, "nfsvers=%s" },
168         { Opt_nfsvers, "vers=%s" },
169         { Opt_minorversion, "minorversion=%s" },
170
171         { Opt_sec, "sec=%s" },
172         { Opt_proto, "proto=%s" },
173         { Opt_mountproto, "mountproto=%s" },
174         { Opt_addr, "addr=%s" },
175         { Opt_clientaddr, "clientaddr=%s" },
176         { Opt_mounthost, "mounthost=%s" },
177         { Opt_mountaddr, "mountaddr=%s" },
178
179         { Opt_lookupcache, "lookupcache=%s" },
180         { Opt_fscache_uniq, "fsc=%s" },
181         { Opt_local_lock, "local_lock=%s" },
182
183         { Opt_err, NULL }
184 };
185
186 enum {
187         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
188
189         Opt_xprt_err
190 };
191
192 static const match_table_t nfs_xprt_protocol_tokens = {
193         { Opt_xprt_udp, "udp" },
194         { Opt_xprt_udp6, "udp6" },
195         { Opt_xprt_tcp, "tcp" },
196         { Opt_xprt_tcp6, "tcp6" },
197         { Opt_xprt_rdma, "rdma" },
198
199         { Opt_xprt_err, NULL }
200 };
201
202 enum {
203         Opt_sec_none, Opt_sec_sys,
204         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
205         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
206         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
207
208         Opt_sec_err
209 };
210
211 static const match_table_t nfs_secflavor_tokens = {
212         { Opt_sec_none, "none" },
213         { Opt_sec_none, "null" },
214         { Opt_sec_sys, "sys" },
215
216         { Opt_sec_krb5, "krb5" },
217         { Opt_sec_krb5i, "krb5i" },
218         { Opt_sec_krb5p, "krb5p" },
219
220         { Opt_sec_lkey, "lkey" },
221         { Opt_sec_lkeyi, "lkeyi" },
222         { Opt_sec_lkeyp, "lkeyp" },
223
224         { Opt_sec_spkm, "spkm3" },
225         { Opt_sec_spkmi, "spkm3i" },
226         { Opt_sec_spkmp, "spkm3p" },
227
228         { Opt_sec_err, NULL }
229 };
230
231 enum {
232         Opt_lookupcache_all, Opt_lookupcache_positive,
233         Opt_lookupcache_none,
234
235         Opt_lookupcache_err
236 };
237
238 static match_table_t nfs_lookupcache_tokens = {
239         { Opt_lookupcache_all, "all" },
240         { Opt_lookupcache_positive, "pos" },
241         { Opt_lookupcache_positive, "positive" },
242         { Opt_lookupcache_none, "none" },
243
244         { Opt_lookupcache_err, NULL }
245 };
246
247 enum {
248         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
249         Opt_local_lock_none,
250
251         Opt_local_lock_err
252 };
253
254 static match_table_t nfs_local_lock_tokens = {
255         { Opt_local_lock_all, "all" },
256         { Opt_local_lock_flock, "flock" },
257         { Opt_local_lock_posix, "posix" },
258         { Opt_local_lock_none, "none" },
259
260         { Opt_local_lock_err, NULL }
261 };
262
263
264 static void nfs_umount_begin(struct super_block *);
265 static int  nfs_statfs(struct dentry *, struct kstatfs *);
266 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
267 static int  nfs_show_devname(struct seq_file *, struct vfsmount *);
268 static int  nfs_show_path(struct seq_file *, struct vfsmount *);
269 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
270 static struct dentry *nfs_fs_mount(struct file_system_type *,
271                 int, const char *, void *);
272 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
273                 int flags, const char *dev_name, void *raw_data);
274 static void nfs_put_super(struct super_block *);
275 static void nfs_kill_super(struct super_block *);
276 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
277
278 static struct file_system_type nfs_fs_type = {
279         .owner          = THIS_MODULE,
280         .name           = "nfs",
281         .mount          = nfs_fs_mount,
282         .kill_sb        = nfs_kill_super,
283         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
284 };
285
286 struct file_system_type nfs_xdev_fs_type = {
287         .owner          = THIS_MODULE,
288         .name           = "nfs",
289         .mount          = nfs_xdev_mount,
290         .kill_sb        = nfs_kill_super,
291         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
292 };
293
294 static const struct super_operations nfs_sops = {
295         .alloc_inode    = nfs_alloc_inode,
296         .destroy_inode  = nfs_destroy_inode,
297         .write_inode    = nfs_write_inode,
298         .put_super      = nfs_put_super,
299         .statfs         = nfs_statfs,
300         .evict_inode    = nfs_evict_inode,
301         .umount_begin   = nfs_umount_begin,
302         .show_options   = nfs_show_options,
303         .show_devname   = nfs_show_devname,
304         .show_path      = nfs_show_path,
305         .show_stats     = nfs_show_stats,
306         .remount_fs     = nfs_remount,
307 };
308
309 #ifdef CONFIG_NFS_V4
310 static int nfs4_validate_text_mount_data(void *options,
311         struct nfs_parsed_mount_data *args, const char *dev_name);
312 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
313         struct nfs_parsed_mount_data *data);
314 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
315         int flags, const char *dev_name, void *raw_data);
316 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
317         int flags, const char *dev_name, void *raw_data);
318 static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
319         int flags, const char *dev_name, void *raw_data);
320 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
321         int flags, const char *dev_name, void *raw_data);
322 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
323         int flags, const char *dev_name, void *raw_data);
324 static void nfs4_kill_super(struct super_block *sb);
325
326 static struct file_system_type nfs4_fs_type = {
327         .owner          = THIS_MODULE,
328         .name           = "nfs4",
329         .mount          = nfs4_mount,
330         .kill_sb        = nfs4_kill_super,
331         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
332 };
333
334 static struct file_system_type nfs4_remote_fs_type = {
335         .owner          = THIS_MODULE,
336         .name           = "nfs4",
337         .mount          = nfs4_remote_mount,
338         .kill_sb        = nfs4_kill_super,
339         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
340 };
341
342 struct file_system_type nfs4_xdev_fs_type = {
343         .owner          = THIS_MODULE,
344         .name           = "nfs4",
345         .mount          = nfs4_xdev_mount,
346         .kill_sb        = nfs4_kill_super,
347         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
348 };
349
350 static struct file_system_type nfs4_remote_referral_fs_type = {
351         .owner          = THIS_MODULE,
352         .name           = "nfs4",
353         .mount          = nfs4_remote_referral_mount,
354         .kill_sb        = nfs4_kill_super,
355         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
356 };
357
358 struct file_system_type nfs4_referral_fs_type = {
359         .owner          = THIS_MODULE,
360         .name           = "nfs4",
361         .mount          = nfs4_referral_mount,
362         .kill_sb        = nfs4_kill_super,
363         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
364 };
365
366 static const struct super_operations nfs4_sops = {
367         .alloc_inode    = nfs_alloc_inode,
368         .destroy_inode  = nfs_destroy_inode,
369         .write_inode    = nfs_write_inode,
370         .put_super      = nfs_put_super,
371         .statfs         = nfs_statfs,
372         .evict_inode    = nfs4_evict_inode,
373         .umount_begin   = nfs_umount_begin,
374         .show_options   = nfs_show_options,
375         .show_devname   = nfs_show_devname,
376         .show_path      = nfs_show_path,
377         .show_stats     = nfs_show_stats,
378         .remount_fs     = nfs_remount,
379 };
380 #endif
381
382 static struct shrinker acl_shrinker = {
383         .shrink         = nfs_access_cache_shrinker,
384         .seeks          = DEFAULT_SEEKS,
385 };
386
387 /*
388  * Register the NFS filesystems
389  */
390 int __init register_nfs_fs(void)
391 {
392         int ret;
393
394         ret = register_filesystem(&nfs_fs_type);
395         if (ret < 0)
396                 goto error_0;
397
398         ret = nfs_register_sysctl();
399         if (ret < 0)
400                 goto error_1;
401 #ifdef CONFIG_NFS_V4
402         ret = register_filesystem(&nfs4_fs_type);
403         if (ret < 0)
404                 goto error_2;
405 #endif
406         register_shrinker(&acl_shrinker);
407         return 0;
408
409 #ifdef CONFIG_NFS_V4
410 error_2:
411         nfs_unregister_sysctl();
412 #endif
413 error_1:
414         unregister_filesystem(&nfs_fs_type);
415 error_0:
416         return ret;
417 }
418
419 /*
420  * Unregister the NFS filesystems
421  */
422 void __exit unregister_nfs_fs(void)
423 {
424         unregister_shrinker(&acl_shrinker);
425 #ifdef CONFIG_NFS_V4
426         unregister_filesystem(&nfs4_fs_type);
427 #endif
428         nfs_unregister_sysctl();
429         unregister_filesystem(&nfs_fs_type);
430 }
431
432 void nfs_sb_active(struct super_block *sb)
433 {
434         struct nfs_server *server = NFS_SB(sb);
435
436         if (atomic_inc_return(&server->active) == 1)
437                 atomic_inc(&sb->s_active);
438 }
439
440 void nfs_sb_deactive(struct super_block *sb)
441 {
442         struct nfs_server *server = NFS_SB(sb);
443
444         if (atomic_dec_and_test(&server->active))
445                 deactivate_super(sb);
446 }
447
448 /*
449  * Deliver file system statistics to userspace
450  */
451 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
452 {
453         struct nfs_server *server = NFS_SB(dentry->d_sb);
454         unsigned char blockbits;
455         unsigned long blockres;
456         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
457         struct nfs_fsstat res;
458         int error = -ENOMEM;
459
460         res.fattr = nfs_alloc_fattr();
461         if (res.fattr == NULL)
462                 goto out_err;
463
464         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
465         if (unlikely(error == -ESTALE)) {
466                 struct dentry *pd_dentry;
467
468                 pd_dentry = dget_parent(dentry);
469                 if (pd_dentry != NULL) {
470                         nfs_zap_caches(pd_dentry->d_inode);
471                         dput(pd_dentry);
472                 }
473         }
474         nfs_free_fattr(res.fattr);
475         if (error < 0)
476                 goto out_err;
477
478         buf->f_type = NFS_SUPER_MAGIC;
479
480         /*
481          * Current versions of glibc do not correctly handle the
482          * case where f_frsize != f_bsize.  Eventually we want to
483          * report the value of wtmult in this field.
484          */
485         buf->f_frsize = dentry->d_sb->s_blocksize;
486
487         /*
488          * On most *nix systems, f_blocks, f_bfree, and f_bavail
489          * are reported in units of f_frsize.  Linux hasn't had
490          * an f_frsize field in its statfs struct until recently,
491          * thus historically Linux's sys_statfs reports these
492          * fields in units of f_bsize.
493          */
494         buf->f_bsize = dentry->d_sb->s_blocksize;
495         blockbits = dentry->d_sb->s_blocksize_bits;
496         blockres = (1 << blockbits) - 1;
497         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
498         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
499         buf->f_bavail = (res.abytes + blockres) >> blockbits;
500
501         buf->f_files = res.tfiles;
502         buf->f_ffree = res.afiles;
503
504         buf->f_namelen = server->namelen;
505
506         return 0;
507
508  out_err:
509         dprintk("%s: statfs error = %d\n", __func__, -error);
510         return error;
511 }
512
513 /*
514  * Map the security flavour number to a name
515  */
516 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
517 {
518         static const struct {
519                 rpc_authflavor_t flavour;
520                 const char *str;
521         } sec_flavours[] = {
522                 { RPC_AUTH_NULL, "null" },
523                 { RPC_AUTH_UNIX, "sys" },
524                 { RPC_AUTH_GSS_KRB5, "krb5" },
525                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
526                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
527                 { RPC_AUTH_GSS_LKEY, "lkey" },
528                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
529                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
530                 { RPC_AUTH_GSS_SPKM, "spkm" },
531                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
532                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
533                 { UINT_MAX, "unknown" }
534         };
535         int i;
536
537         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
538                 if (sec_flavours[i].flavour == flavour)
539                         break;
540         }
541         return sec_flavours[i].str;
542 }
543
544 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
545                                   int showdefaults)
546 {
547         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
548
549         seq_printf(m, ",mountproto=");
550         switch (sap->sa_family) {
551         case AF_INET:
552                 switch (nfss->mountd_protocol) {
553                 case IPPROTO_UDP:
554                         seq_printf(m, RPCBIND_NETID_UDP);
555                         break;
556                 case IPPROTO_TCP:
557                         seq_printf(m, RPCBIND_NETID_TCP);
558                         break;
559                 default:
560                         if (showdefaults)
561                                 seq_printf(m, "auto");
562                 }
563                 break;
564         case AF_INET6:
565                 switch (nfss->mountd_protocol) {
566                 case IPPROTO_UDP:
567                         seq_printf(m, RPCBIND_NETID_UDP6);
568                         break;
569                 case IPPROTO_TCP:
570                         seq_printf(m, RPCBIND_NETID_TCP6);
571                         break;
572                 default:
573                         if (showdefaults)
574                                 seq_printf(m, "auto");
575                 }
576                 break;
577         default:
578                 if (showdefaults)
579                         seq_printf(m, "auto");
580         }
581 }
582
583 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
584                                     int showdefaults)
585 {
586         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
587
588         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
589                 return;
590
591         switch (sap->sa_family) {
592         case AF_INET: {
593                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
594                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
595                 break;
596         }
597         case AF_INET6: {
598                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
599                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
600                 break;
601         }
602         default:
603                 if (showdefaults)
604                         seq_printf(m, ",mountaddr=unspecified");
605         }
606
607         if (nfss->mountd_version || showdefaults)
608                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
609         if ((nfss->mountd_port &&
610                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
611                 showdefaults)
612                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
613
614         nfs_show_mountd_netid(m, nfss, showdefaults);
615 }
616
617 #ifdef CONFIG_NFS_V4
618 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
619                                     int showdefaults)
620 {
621         struct nfs_client *clp = nfss->nfs_client;
622
623         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
624         seq_printf(m, ",minorversion=%u", clp->cl_minorversion);
625 }
626 #else
627 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
628                                     int showdefaults)
629 {
630 }
631 #endif
632
633 /*
634  * Describe the mount options in force on this server representation
635  */
636 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
637                                    int showdefaults)
638 {
639         static const struct proc_nfs_info {
640                 int flag;
641                 const char *str;
642                 const char *nostr;
643         } nfs_info[] = {
644                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
645                 { NFS_MOUNT_POSIX, ",posix", "" },
646                 { NFS_MOUNT_NOCTO, ",nocto", "" },
647                 { NFS_MOUNT_NOAC, ",noac", "" },
648                 { NFS_MOUNT_NONLM, ",nolock", "" },
649                 { NFS_MOUNT_NOACL, ",noacl", "" },
650                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
651                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
652                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
653                 { 0, NULL, NULL }
654         };
655         const struct proc_nfs_info *nfs_infop;
656         struct nfs_client *clp = nfss->nfs_client;
657         u32 version = clp->rpc_ops->version;
658         int local_flock, local_fcntl;
659
660         seq_printf(m, ",vers=%u", version);
661         seq_printf(m, ",rsize=%u", nfss->rsize);
662         seq_printf(m, ",wsize=%u", nfss->wsize);
663         if (nfss->bsize != 0)
664                 seq_printf(m, ",bsize=%u", nfss->bsize);
665         seq_printf(m, ",namlen=%u", nfss->namelen);
666         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
667                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
668         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
669                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
670         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
671                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
672         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
673                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
674         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
675                 if (nfss->flags & nfs_infop->flag)
676                         seq_puts(m, nfs_infop->str);
677                 else
678                         seq_puts(m, nfs_infop->nostr);
679         }
680         seq_printf(m, ",proto=%s",
681                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
682         if (version == 4) {
683                 if (nfss->port != NFS_PORT)
684                         seq_printf(m, ",port=%u", nfss->port);
685         } else
686                 if (nfss->port)
687                         seq_printf(m, ",port=%u", nfss->port);
688
689         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
690         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
691         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
692
693         if (version != 4)
694                 nfs_show_mountd_options(m, nfss, showdefaults);
695         else
696                 nfs_show_nfsv4_options(m, nfss, showdefaults);
697
698         if (nfss->options & NFS_OPTION_FSCACHE)
699                 seq_printf(m, ",fsc");
700
701         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
702                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
703                         seq_printf(m, ",lookupcache=none");
704                 else
705                         seq_printf(m, ",lookupcache=pos");
706         }
707
708         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
709         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
710
711         if (!local_flock && !local_fcntl)
712                 seq_printf(m, ",local_lock=none");
713         else if (local_flock && local_fcntl)
714                 seq_printf(m, ",local_lock=all");
715         else if (local_flock)
716                 seq_printf(m, ",local_lock=flock");
717         else
718                 seq_printf(m, ",local_lock=posix");
719 }
720
721 /*
722  * Describe the mount options on this VFS mountpoint
723  */
724 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
725 {
726         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
727
728         nfs_show_mount_options(m, nfss, 0);
729
730         seq_printf(m, ",addr=%s",
731                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
732                                                         RPC_DISPLAY_ADDR));
733
734         return 0;
735 }
736
737 #ifdef CONFIG_NFS_V4
738 #ifdef CONFIG_NFS_V4_1
739 static void show_sessions(struct seq_file *m, struct nfs_server *server)
740 {
741         if (nfs4_has_session(server->nfs_client))
742                 seq_printf(m, ",sessions");
743 }
744 #else
745 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
746 #endif
747 #endif
748
749 #ifdef CONFIG_NFS_V4
750 #ifdef CONFIG_NFS_V4_1
751 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
752 {
753         seq_printf(m, ",pnfs=");
754         if (server->pnfs_curr_ld)
755                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
756         else
757                 seq_printf(m, "not configured");
758 }
759 #else
760 static void show_pnfs(struct seq_file *m, struct nfs_server *server) {}
761 #endif
762 #endif
763
764 static int nfs_show_devname(struct seq_file *m, struct vfsmount *mnt)
765 {
766         char *page = (char *) __get_free_page(GFP_KERNEL);
767         char *devname, *dummy;
768         int err = 0;
769         if (!page)
770                 return -ENOMEM;
771         devname = nfs_path(&dummy, mnt->mnt_root, page, PAGE_SIZE);
772         if (IS_ERR(devname))
773                 err = PTR_ERR(devname);
774         else
775                 seq_escape(m, devname, " \t\n\\");
776         free_page((unsigned long)page);
777         return err;
778 }
779
780 static int nfs_show_path(struct seq_file *m, struct vfsmount *mnt)
781 {
782         seq_puts(m, "/");
783         return 0;
784 }
785
786 /*
787  * Present statistical information for this VFS mountpoint
788  */
789 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
790 {
791         int i, cpu;
792         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
793         struct rpc_auth *auth = nfss->client->cl_auth;
794         struct nfs_iostats totals = { };
795
796         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
797
798         /*
799          * Display all mount option settings
800          */
801         seq_printf(m, "\n\topts:\t");
802         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
803         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
804         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
805         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
806         nfs_show_mount_options(m, nfss, 1);
807
808         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
809
810         seq_printf(m, "\n\tcaps:\t");
811         seq_printf(m, "caps=0x%x", nfss->caps);
812         seq_printf(m, ",wtmult=%u", nfss->wtmult);
813         seq_printf(m, ",dtsize=%u", nfss->dtsize);
814         seq_printf(m, ",bsize=%u", nfss->bsize);
815         seq_printf(m, ",namlen=%u", nfss->namelen);
816
817 #ifdef CONFIG_NFS_V4
818         if (nfss->nfs_client->rpc_ops->version == 4) {
819                 seq_printf(m, "\n\tnfsv4:\t");
820                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
821                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
822                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
823                 show_sessions(m, nfss);
824                 show_pnfs(m, nfss);
825         }
826 #endif
827
828         /*
829          * Display security flavor in effect for this mount
830          */
831         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
832         if (auth->au_flavor)
833                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
834
835         /*
836          * Display superblock I/O counters
837          */
838         for_each_possible_cpu(cpu) {
839                 struct nfs_iostats *stats;
840
841                 preempt_disable();
842                 stats = per_cpu_ptr(nfss->io_stats, cpu);
843
844                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
845                         totals.events[i] += stats->events[i];
846                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
847                         totals.bytes[i] += stats->bytes[i];
848 #ifdef CONFIG_NFS_FSCACHE
849                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
850                         totals.fscache[i] += stats->fscache[i];
851 #endif
852
853                 preempt_enable();
854         }
855
856         seq_printf(m, "\n\tevents:\t");
857         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
858                 seq_printf(m, "%lu ", totals.events[i]);
859         seq_printf(m, "\n\tbytes:\t");
860         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
861                 seq_printf(m, "%Lu ", totals.bytes[i]);
862 #ifdef CONFIG_NFS_FSCACHE
863         if (nfss->options & NFS_OPTION_FSCACHE) {
864                 seq_printf(m, "\n\tfsc:\t");
865                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
866                         seq_printf(m, "%Lu ", totals.bytes[i]);
867         }
868 #endif
869         seq_printf(m, "\n");
870
871         rpc_print_iostats(m, nfss->client);
872
873         return 0;
874 }
875
876 /*
877  * Begin unmount by attempting to remove all automounted mountpoints we added
878  * in response to xdev traversals and referrals
879  */
880 static void nfs_umount_begin(struct super_block *sb)
881 {
882         struct nfs_server *server;
883         struct rpc_clnt *rpc;
884
885         server = NFS_SB(sb);
886         /* -EIO all pending I/O */
887         rpc = server->client_acl;
888         if (!IS_ERR(rpc))
889                 rpc_killall_tasks(rpc);
890         rpc = server->client;
891         if (!IS_ERR(rpc))
892                 rpc_killall_tasks(rpc);
893 }
894
895 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
896 {
897         struct nfs_parsed_mount_data *data;
898
899         data = kzalloc(sizeof(*data), GFP_KERNEL);
900         if (data) {
901                 data->acregmin          = NFS_DEF_ACREGMIN;
902                 data->acregmax          = NFS_DEF_ACREGMAX;
903                 data->acdirmin          = NFS_DEF_ACDIRMIN;
904                 data->acdirmax          = NFS_DEF_ACDIRMAX;
905                 data->mount_server.port = NFS_UNSPEC_PORT;
906                 data->nfs_server.port   = NFS_UNSPEC_PORT;
907                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
908                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
909                 data->auth_flavor_len   = 1;
910                 data->version           = version;
911                 data->minorversion      = 0;
912                 security_init_mnt_opts(&data->lsm_opts);
913         }
914         return data;
915 }
916
917 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
918 {
919         if (data) {
920                 kfree(data->client_address);
921                 kfree(data->mount_server.hostname);
922                 kfree(data->nfs_server.export_path);
923                 kfree(data->nfs_server.hostname);
924                 kfree(data->fscache_uniq);
925                 security_free_mnt_opts(&data->lsm_opts);
926                 kfree(data);
927         }
928 }
929
930 /*
931  * Sanity-check a server address provided by the mount command.
932  *
933  * Address family must be initialized, and address must not be
934  * the ANY address for that family.
935  */
936 static int nfs_verify_server_address(struct sockaddr *addr)
937 {
938         switch (addr->sa_family) {
939         case AF_INET: {
940                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
941                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
942         }
943         case AF_INET6: {
944                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
945                 return !ipv6_addr_any(sa);
946         }
947         }
948
949         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
950         return 0;
951 }
952
953 /*
954  * Select between a default port value and a user-specified port value.
955  * If a zero value is set, then autobind will be used.
956  */
957 static void nfs_set_port(struct sockaddr *sap, int *port,
958                                  const unsigned short default_port)
959 {
960         if (*port == NFS_UNSPEC_PORT)
961                 *port = default_port;
962
963         rpc_set_port(sap, *port);
964 }
965
966 /*
967  * Sanity check the NFS transport protocol.
968  *
969  */
970 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
971 {
972         switch (mnt->nfs_server.protocol) {
973         case XPRT_TRANSPORT_UDP:
974         case XPRT_TRANSPORT_TCP:
975         case XPRT_TRANSPORT_RDMA:
976                 break;
977         default:
978                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
979         }
980 }
981
982 /*
983  * For text based NFSv2/v3 mounts, the mount protocol transport default
984  * settings should depend upon the specified NFS transport.
985  */
986 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
987 {
988         nfs_validate_transport_protocol(mnt);
989
990         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
991             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
992                         return;
993         switch (mnt->nfs_server.protocol) {
994         case XPRT_TRANSPORT_UDP:
995                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
996                 break;
997         case XPRT_TRANSPORT_TCP:
998         case XPRT_TRANSPORT_RDMA:
999                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1000         }
1001 }
1002
1003 /*
1004  * Parse the value of the 'sec=' option.
1005  */
1006 static int nfs_parse_security_flavors(char *value,
1007                                       struct nfs_parsed_mount_data *mnt)
1008 {
1009         substring_t args[MAX_OPT_ARGS];
1010
1011         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1012
1013         switch (match_token(value, nfs_secflavor_tokens, args)) {
1014         case Opt_sec_none:
1015                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1016                 break;
1017         case Opt_sec_sys:
1018                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1019                 break;
1020         case Opt_sec_krb5:
1021                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1022                 break;
1023         case Opt_sec_krb5i:
1024                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1025                 break;
1026         case Opt_sec_krb5p:
1027                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1028                 break;
1029         case Opt_sec_lkey:
1030                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1031                 break;
1032         case Opt_sec_lkeyi:
1033                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1034                 break;
1035         case Opt_sec_lkeyp:
1036                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1037                 break;
1038         case Opt_sec_spkm:
1039                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1040                 break;
1041         case Opt_sec_spkmi:
1042                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1043                 break;
1044         case Opt_sec_spkmp:
1045                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1046                 break;
1047         default:
1048                 return 0;
1049         }
1050
1051         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1052         mnt->auth_flavor_len = 1;
1053         return 1;
1054 }
1055
1056 static int nfs_get_option_str(substring_t args[], char **option)
1057 {
1058         kfree(*option);
1059         *option = match_strdup(args);
1060         return !option;
1061 }
1062
1063 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1064 {
1065         int rc;
1066         char *string;
1067
1068         string = match_strdup(args);
1069         if (string == NULL)
1070                 return -ENOMEM;
1071         rc = strict_strtoul(string, 10, option);
1072         kfree(string);
1073
1074         return rc;
1075 }
1076
1077 /*
1078  * Error-check and convert a string of mount options from user space into
1079  * a data structure.  The whole mount string is processed; bad options are
1080  * skipped as they are encountered.  If there were no errors, return 1;
1081  * otherwise return 0 (zero).
1082  */
1083 static int nfs_parse_mount_options(char *raw,
1084                                    struct nfs_parsed_mount_data *mnt)
1085 {
1086         char *p, *string, *secdata;
1087         int rc, sloppy = 0, invalid_option = 0;
1088         unsigned short protofamily = AF_UNSPEC;
1089         unsigned short mountfamily = AF_UNSPEC;
1090
1091         if (!raw) {
1092                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1093                 return 1;
1094         }
1095         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1096
1097         secdata = alloc_secdata();
1098         if (!secdata)
1099                 goto out_nomem;
1100
1101         rc = security_sb_copy_data(raw, secdata);
1102         if (rc)
1103                 goto out_security_failure;
1104
1105         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1106         if (rc)
1107                 goto out_security_failure;
1108
1109         free_secdata(secdata);
1110
1111         while ((p = strsep(&raw, ",")) != NULL) {
1112                 substring_t args[MAX_OPT_ARGS];
1113                 unsigned long option;
1114                 int token;
1115
1116                 if (!*p)
1117                         continue;
1118
1119                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1120
1121                 token = match_token(p, nfs_mount_option_tokens, args);
1122                 switch (token) {
1123
1124                 /*
1125                  * boolean options:  foo/nofoo
1126                  */
1127                 case Opt_soft:
1128                         mnt->flags |= NFS_MOUNT_SOFT;
1129                         break;
1130                 case Opt_hard:
1131                         mnt->flags &= ~NFS_MOUNT_SOFT;
1132                         break;
1133                 case Opt_posix:
1134                         mnt->flags |= NFS_MOUNT_POSIX;
1135                         break;
1136                 case Opt_noposix:
1137                         mnt->flags &= ~NFS_MOUNT_POSIX;
1138                         break;
1139                 case Opt_cto:
1140                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1141                         break;
1142                 case Opt_nocto:
1143                         mnt->flags |= NFS_MOUNT_NOCTO;
1144                         break;
1145                 case Opt_ac:
1146                         mnt->flags &= ~NFS_MOUNT_NOAC;
1147                         break;
1148                 case Opt_noac:
1149                         mnt->flags |= NFS_MOUNT_NOAC;
1150                         break;
1151                 case Opt_lock:
1152                         mnt->flags &= ~NFS_MOUNT_NONLM;
1153                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1154                                         NFS_MOUNT_LOCAL_FCNTL);
1155                         break;
1156                 case Opt_nolock:
1157                         mnt->flags |= NFS_MOUNT_NONLM;
1158                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1159                                        NFS_MOUNT_LOCAL_FCNTL);
1160                         break;
1161                 case Opt_v2:
1162                         mnt->flags &= ~NFS_MOUNT_VER3;
1163                         mnt->version = 2;
1164                         break;
1165                 case Opt_v3:
1166                         mnt->flags |= NFS_MOUNT_VER3;
1167                         mnt->version = 3;
1168                         break;
1169                 case Opt_v4:
1170                         mnt->flags &= ~NFS_MOUNT_VER3;
1171                         mnt->version = 4;
1172                         break;
1173                 case Opt_udp:
1174                         mnt->flags &= ~NFS_MOUNT_TCP;
1175                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1176                         break;
1177                 case Opt_tcp:
1178                         mnt->flags |= NFS_MOUNT_TCP;
1179                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1180                         break;
1181                 case Opt_rdma:
1182                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1183                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1184                         xprt_load_transport(p);
1185                         break;
1186                 case Opt_acl:
1187                         mnt->flags &= ~NFS_MOUNT_NOACL;
1188                         break;
1189                 case Opt_noacl:
1190                         mnt->flags |= NFS_MOUNT_NOACL;
1191                         break;
1192                 case Opt_rdirplus:
1193                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1194                         break;
1195                 case Opt_nordirplus:
1196                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1197                         break;
1198                 case Opt_sharecache:
1199                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1200                         break;
1201                 case Opt_nosharecache:
1202                         mnt->flags |= NFS_MOUNT_UNSHARED;
1203                         break;
1204                 case Opt_resvport:
1205                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1206                         break;
1207                 case Opt_noresvport:
1208                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1209                         break;
1210                 case Opt_fscache:
1211                         mnt->options |= NFS_OPTION_FSCACHE;
1212                         kfree(mnt->fscache_uniq);
1213                         mnt->fscache_uniq = NULL;
1214                         break;
1215                 case Opt_nofscache:
1216                         mnt->options &= ~NFS_OPTION_FSCACHE;
1217                         kfree(mnt->fscache_uniq);
1218                         mnt->fscache_uniq = NULL;
1219                         break;
1220
1221                 /*
1222                  * options that take numeric values
1223                  */
1224                 case Opt_port:
1225                         if (nfs_get_option_ul(args, &option) ||
1226                             option > USHRT_MAX)
1227                                 goto out_invalid_value;
1228                         mnt->nfs_server.port = option;
1229                         break;
1230                 case Opt_rsize:
1231                         if (nfs_get_option_ul(args, &option))
1232                                 goto out_invalid_value;
1233                         mnt->rsize = option;
1234                         break;
1235                 case Opt_wsize:
1236                         if (nfs_get_option_ul(args, &option))
1237                                 goto out_invalid_value;
1238                         mnt->wsize = option;
1239                         break;
1240                 case Opt_bsize:
1241                         if (nfs_get_option_ul(args, &option))
1242                                 goto out_invalid_value;
1243                         mnt->bsize = option;
1244                         break;
1245                 case Opt_timeo:
1246                         if (nfs_get_option_ul(args, &option) || option == 0)
1247                                 goto out_invalid_value;
1248                         mnt->timeo = option;
1249                         break;
1250                 case Opt_retrans:
1251                         if (nfs_get_option_ul(args, &option) || option == 0)
1252                                 goto out_invalid_value;
1253                         mnt->retrans = option;
1254                         break;
1255                 case Opt_acregmin:
1256                         if (nfs_get_option_ul(args, &option))
1257                                 goto out_invalid_value;
1258                         mnt->acregmin = option;
1259                         break;
1260                 case Opt_acregmax:
1261                         if (nfs_get_option_ul(args, &option))
1262                                 goto out_invalid_value;
1263                         mnt->acregmax = option;
1264                         break;
1265                 case Opt_acdirmin:
1266                         if (nfs_get_option_ul(args, &option))
1267                                 goto out_invalid_value;
1268                         mnt->acdirmin = option;
1269                         break;
1270                 case Opt_acdirmax:
1271                         if (nfs_get_option_ul(args, &option))
1272                                 goto out_invalid_value;
1273                         mnt->acdirmax = option;
1274                         break;
1275                 case Opt_actimeo:
1276                         if (nfs_get_option_ul(args, &option))
1277                                 goto out_invalid_value;
1278                         mnt->acregmin = mnt->acregmax =
1279                         mnt->acdirmin = mnt->acdirmax = option;
1280                         break;
1281                 case Opt_namelen:
1282                         if (nfs_get_option_ul(args, &option))
1283                                 goto out_invalid_value;
1284                         mnt->namlen = option;
1285                         break;
1286                 case Opt_mountport:
1287                         if (nfs_get_option_ul(args, &option) ||
1288                             option > USHRT_MAX)
1289                                 goto out_invalid_value;
1290                         mnt->mount_server.port = option;
1291                         break;
1292                 case Opt_mountvers:
1293                         if (nfs_get_option_ul(args, &option) ||
1294                             option < NFS_MNT_VERSION ||
1295                             option > NFS_MNT3_VERSION)
1296                                 goto out_invalid_value;
1297                         mnt->mount_server.version = option;
1298                         break;
1299                 case Opt_nfsvers:
1300                         if (nfs_get_option_ul(args, &option))
1301                                 goto out_invalid_value;
1302                         switch (option) {
1303                         case NFS2_VERSION:
1304                                 mnt->flags &= ~NFS_MOUNT_VER3;
1305                                 mnt->version = 2;
1306                                 break;
1307                         case NFS3_VERSION:
1308                                 mnt->flags |= NFS_MOUNT_VER3;
1309                                 mnt->version = 3;
1310                                 break;
1311                         case NFS4_VERSION:
1312                                 mnt->flags &= ~NFS_MOUNT_VER3;
1313                                 mnt->version = 4;
1314                                 break;
1315                         default:
1316                                 goto out_invalid_value;
1317                         }
1318                         break;
1319                 case Opt_minorversion:
1320                         if (nfs_get_option_ul(args, &option))
1321                                 goto out_invalid_value;
1322                         if (option > NFS4_MAX_MINOR_VERSION)
1323                                 goto out_invalid_value;
1324                         mnt->minorversion = option;
1325                         break;
1326
1327                 /*
1328                  * options that take text values
1329                  */
1330                 case Opt_sec:
1331                         string = match_strdup(args);
1332                         if (string == NULL)
1333                                 goto out_nomem;
1334                         rc = nfs_parse_security_flavors(string, mnt);
1335                         kfree(string);
1336                         if (!rc) {
1337                                 dfprintk(MOUNT, "NFS:   unrecognized "
1338                                                 "security flavor\n");
1339                                 return 0;
1340                         }
1341                         break;
1342                 case Opt_proto:
1343                         string = match_strdup(args);
1344                         if (string == NULL)
1345                                 goto out_nomem;
1346                         token = match_token(string,
1347                                             nfs_xprt_protocol_tokens, args);
1348
1349                         protofamily = AF_INET;
1350                         switch (token) {
1351                         case Opt_xprt_udp6:
1352                                 protofamily = AF_INET6;
1353                         case Opt_xprt_udp:
1354                                 mnt->flags &= ~NFS_MOUNT_TCP;
1355                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1356                                 break;
1357                         case Opt_xprt_tcp6:
1358                                 protofamily = AF_INET6;
1359                         case Opt_xprt_tcp:
1360                                 mnt->flags |= NFS_MOUNT_TCP;
1361                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1362                                 break;
1363                         case Opt_xprt_rdma:
1364                                 /* vector side protocols to TCP */
1365                                 mnt->flags |= NFS_MOUNT_TCP;
1366                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1367                                 xprt_load_transport(string);
1368                                 break;
1369                         default:
1370                                 dfprintk(MOUNT, "NFS:   unrecognized "
1371                                                 "transport protocol\n");
1372                                 kfree(string);
1373                                 return 0;
1374                         }
1375                         kfree(string);
1376                         break;
1377                 case Opt_mountproto:
1378                         string = match_strdup(args);
1379                         if (string == NULL)
1380                                 goto out_nomem;
1381                         token = match_token(string,
1382                                             nfs_xprt_protocol_tokens, args);
1383                         kfree(string);
1384
1385                         mountfamily = AF_INET;
1386                         switch (token) {
1387                         case Opt_xprt_udp6:
1388                                 mountfamily = AF_INET6;
1389                         case Opt_xprt_udp:
1390                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1391                                 break;
1392                         case Opt_xprt_tcp6:
1393                                 mountfamily = AF_INET6;
1394                         case Opt_xprt_tcp:
1395                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1396                                 break;
1397                         case Opt_xprt_rdma: /* not used for side protocols */
1398                         default:
1399                                 dfprintk(MOUNT, "NFS:   unrecognized "
1400                                                 "transport protocol\n");
1401                                 return 0;
1402                         }
1403                         break;
1404                 case Opt_addr:
1405                         string = match_strdup(args);
1406                         if (string == NULL)
1407                                 goto out_nomem;
1408                         mnt->nfs_server.addrlen =
1409                                 rpc_pton(string, strlen(string),
1410                                         (struct sockaddr *)
1411                                         &mnt->nfs_server.address,
1412                                         sizeof(mnt->nfs_server.address));
1413                         kfree(string);
1414                         if (mnt->nfs_server.addrlen == 0)
1415                                 goto out_invalid_address;
1416                         break;
1417                 case Opt_clientaddr:
1418                         if (nfs_get_option_str(args, &mnt->client_address))
1419                                 goto out_nomem;
1420                         break;
1421                 case Opt_mounthost:
1422                         if (nfs_get_option_str(args,
1423                                                &mnt->mount_server.hostname))
1424                                 goto out_nomem;
1425                         break;
1426                 case Opt_mountaddr:
1427                         string = match_strdup(args);
1428                         if (string == NULL)
1429                                 goto out_nomem;
1430                         mnt->mount_server.addrlen =
1431                                 rpc_pton(string, strlen(string),
1432                                         (struct sockaddr *)
1433                                         &mnt->mount_server.address,
1434                                         sizeof(mnt->mount_server.address));
1435                         kfree(string);
1436                         if (mnt->mount_server.addrlen == 0)
1437                                 goto out_invalid_address;
1438                         break;
1439                 case Opt_lookupcache:
1440                         string = match_strdup(args);
1441                         if (string == NULL)
1442                                 goto out_nomem;
1443                         token = match_token(string,
1444                                         nfs_lookupcache_tokens, args);
1445                         kfree(string);
1446                         switch (token) {
1447                                 case Opt_lookupcache_all:
1448                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1449                                         break;
1450                                 case Opt_lookupcache_positive:
1451                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1452                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1453                                         break;
1454                                 case Opt_lookupcache_none:
1455                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1456                                         break;
1457                                 default:
1458                                         dfprintk(MOUNT, "NFS:   invalid "
1459                                                         "lookupcache argument\n");
1460                                         return 0;
1461                         };
1462                         break;
1463                 case Opt_fscache_uniq:
1464                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1465                                 goto out_nomem;
1466                         mnt->options |= NFS_OPTION_FSCACHE;
1467                         break;
1468                 case Opt_local_lock:
1469                         string = match_strdup(args);
1470                         if (string == NULL)
1471                                 goto out_nomem;
1472                         token = match_token(string, nfs_local_lock_tokens,
1473                                         args);
1474                         kfree(string);
1475                         switch (token) {
1476                         case Opt_local_lock_all:
1477                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1478                                                NFS_MOUNT_LOCAL_FCNTL);
1479                                 break;
1480                         case Opt_local_lock_flock:
1481                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1482                                 break;
1483                         case Opt_local_lock_posix:
1484                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1485                                 break;
1486                         case Opt_local_lock_none:
1487                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1488                                                 NFS_MOUNT_LOCAL_FCNTL);
1489                                 break;
1490                         default:
1491                                 dfprintk(MOUNT, "NFS:   invalid "
1492                                                 "local_lock argument\n");
1493                                 return 0;
1494                         };
1495                         break;
1496
1497                 /*
1498                  * Special options
1499                  */
1500                 case Opt_sloppy:
1501                         sloppy = 1;
1502                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1503                         break;
1504                 case Opt_userspace:
1505                 case Opt_deprecated:
1506                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1507                                         "'%s'\n", p);
1508                         break;
1509
1510                 default:
1511                         invalid_option = 1;
1512                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1513                                         "'%s'\n", p);
1514                 }
1515         }
1516
1517         if (!sloppy && invalid_option)
1518                 return 0;
1519
1520         /*
1521          * verify that any proto=/mountproto= options match the address
1522          * familiies in the addr=/mountaddr= options.
1523          */
1524         if (protofamily != AF_UNSPEC &&
1525             protofamily != mnt->nfs_server.address.ss_family)
1526                 goto out_proto_mismatch;
1527
1528         if (mountfamily != AF_UNSPEC) {
1529                 if (mnt->mount_server.addrlen) {
1530                         if (mountfamily != mnt->mount_server.address.ss_family)
1531                                 goto out_mountproto_mismatch;
1532                 } else {
1533                         if (mountfamily != mnt->nfs_server.address.ss_family)
1534                                 goto out_mountproto_mismatch;
1535                 }
1536         }
1537
1538         return 1;
1539
1540 out_mountproto_mismatch:
1541         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1542                          "option\n");
1543         return 0;
1544 out_proto_mismatch:
1545         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1546         return 0;
1547 out_invalid_address:
1548         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1549         return 0;
1550 out_invalid_value:
1551         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1552         return 0;
1553 out_nomem:
1554         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1555         return 0;
1556 out_security_failure:
1557         free_secdata(secdata);
1558         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1559         return 0;
1560 }
1561
1562 /*
1563  * Match the requested auth flavors with the list returned by
1564  * the server.  Returns zero and sets the mount's authentication
1565  * flavor on success; returns -EACCES if server does not support
1566  * the requested flavor.
1567  */
1568 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1569                              struct nfs_mount_request *request)
1570 {
1571         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1572
1573         /*
1574          * Certain releases of Linux's mountd return an empty
1575          * flavor list.  To prevent behavioral regression with
1576          * these servers (ie. rejecting mounts that used to
1577          * succeed), revert to pre-2.6.32 behavior (no checking)
1578          * if the returned flavor list is empty.
1579          */
1580         if (server_authlist_len == 0)
1581                 return 0;
1582
1583         /*
1584          * We avoid sophisticated negotiating here, as there are
1585          * plenty of cases where we can get it wrong, providing
1586          * either too little or too much security.
1587          *
1588          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1589          * flavor listed first.  However, some servers list
1590          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1591          * preferred default, in args->auth_flavors[0] if user
1592          * didn't specify sec= mount option.
1593          */
1594         for (i = 0; i < args->auth_flavor_len; i++)
1595                 for (j = 0; j < server_authlist_len; j++)
1596                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1597                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1598                                         request->auth_flavs[j]);
1599                                 args->auth_flavors[0] = request->auth_flavs[j];
1600                                 return 0;
1601                         }
1602
1603         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1604         nfs_umount(request);
1605         return -EACCES;
1606 }
1607
1608 /*
1609  * Use the remote server's MOUNT service to request the NFS file handle
1610  * corresponding to the provided path.
1611  */
1612 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1613                          struct nfs_fh *root_fh)
1614 {
1615         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1616         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1617         struct nfs_mount_request request = {
1618                 .sap            = (struct sockaddr *)
1619                                                 &args->mount_server.address,
1620                 .dirpath        = args->nfs_server.export_path,
1621                 .protocol       = args->mount_server.protocol,
1622                 .fh             = root_fh,
1623                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1624                 .auth_flav_len  = &server_authlist_len,
1625                 .auth_flavs     = server_authlist,
1626         };
1627         int status;
1628
1629         if (args->mount_server.version == 0) {
1630                 switch (args->version) {
1631                         default:
1632                                 args->mount_server.version = NFS_MNT3_VERSION;
1633                                 break;
1634                         case 2:
1635                                 args->mount_server.version = NFS_MNT_VERSION;
1636                 }
1637         }
1638         request.version = args->mount_server.version;
1639
1640         if (args->mount_server.hostname)
1641                 request.hostname = args->mount_server.hostname;
1642         else
1643                 request.hostname = args->nfs_server.hostname;
1644
1645         /*
1646          * Construct the mount server's address.
1647          */
1648         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1649                 memcpy(request.sap, &args->nfs_server.address,
1650                        args->nfs_server.addrlen);
1651                 args->mount_server.addrlen = args->nfs_server.addrlen;
1652         }
1653         request.salen = args->mount_server.addrlen;
1654         nfs_set_port(request.sap, &args->mount_server.port, 0);
1655
1656         /*
1657          * Now ask the mount server to map our export path
1658          * to a file handle.
1659          */
1660         status = nfs_mount(&request);
1661         if (status != 0) {
1662                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1663                                 request.hostname, status);
1664                 return status;
1665         }
1666
1667         /*
1668          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1669          */
1670         if (args->mount_server.version != NFS_MNT3_VERSION)
1671                 return 0;
1672         return nfs_walk_authlist(args, &request);
1673 }
1674
1675 /*
1676  * Split "dev_name" into "hostname:export_path".
1677  *
1678  * The leftmost colon demarks the split between the server's hostname
1679  * and the export path.  If the hostname starts with a left square
1680  * bracket, then it may contain colons.
1681  *
1682  * Note: caller frees hostname and export path, even on error.
1683  */
1684 static int nfs_parse_devname(const char *dev_name,
1685                              char **hostname, size_t maxnamlen,
1686                              char **export_path, size_t maxpathlen)
1687 {
1688         size_t len;
1689         char *end;
1690
1691         /* Is the host name protected with square brakcets? */
1692         if (*dev_name == '[') {
1693                 end = strchr(++dev_name, ']');
1694                 if (end == NULL || end[1] != ':')
1695                         goto out_bad_devname;
1696
1697                 len = end - dev_name;
1698                 end++;
1699         } else {
1700                 char *comma;
1701
1702                 end = strchr(dev_name, ':');
1703                 if (end == NULL)
1704                         goto out_bad_devname;
1705                 len = end - dev_name;
1706
1707                 /* kill possible hostname list: not supported */
1708                 comma = strchr(dev_name, ',');
1709                 if (comma != NULL && comma < end)
1710                         *comma = 0;
1711         }
1712
1713         if (len > maxnamlen)
1714                 goto out_hostname;
1715
1716         /* N.B. caller will free nfs_server.hostname in all cases */
1717         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1718         if (*hostname == NULL)
1719                 goto out_nomem;
1720         len = strlen(++end);
1721         if (len > maxpathlen)
1722                 goto out_path;
1723         *export_path = kstrndup(end, len, GFP_KERNEL);
1724         if (!*export_path)
1725                 goto out_nomem;
1726
1727         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1728         return 0;
1729
1730 out_bad_devname:
1731         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1732         return -EINVAL;
1733
1734 out_nomem:
1735         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1736         return -ENOMEM;
1737
1738 out_hostname:
1739         dfprintk(MOUNT, "NFS: server hostname too long\n");
1740         return -ENAMETOOLONG;
1741
1742 out_path:
1743         dfprintk(MOUNT, "NFS: export pathname too long\n");
1744         return -ENAMETOOLONG;
1745 }
1746
1747 /*
1748  * Validate the NFS2/NFS3 mount data
1749  * - fills in the mount root filehandle
1750  *
1751  * For option strings, user space handles the following behaviors:
1752  *
1753  * + DNS: mapping server host name to IP address ("addr=" option)
1754  *
1755  * + failure mode: how to behave if a mount request can't be handled
1756  *   immediately ("fg/bg" option)
1757  *
1758  * + retry: how often to retry a mount request ("retry=" option)
1759  *
1760  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1761  *   mountproto=tcp after mountproto=udp, and so on
1762  */
1763 static int nfs_validate_mount_data(void *options,
1764                                    struct nfs_parsed_mount_data *args,
1765                                    struct nfs_fh *mntfh,
1766                                    const char *dev_name)
1767 {
1768         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1769         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1770
1771         if (data == NULL)
1772                 goto out_no_data;
1773
1774         switch (data->version) {
1775         case 1:
1776                 data->namlen = 0;
1777         case 2:
1778                 data->bsize = 0;
1779         case 3:
1780                 if (data->flags & NFS_MOUNT_VER3)
1781                         goto out_no_v3;
1782                 data->root.size = NFS2_FHSIZE;
1783                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1784         case 4:
1785                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1786                         goto out_no_sec;
1787         case 5:
1788                 memset(data->context, 0, sizeof(data->context));
1789         case 6:
1790                 if (data->flags & NFS_MOUNT_VER3) {
1791                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1792                                 goto out_invalid_fh;
1793                         mntfh->size = data->root.size;
1794                         args->version = 3;
1795                 } else {
1796                         mntfh->size = NFS2_FHSIZE;
1797                         args->version = 2;
1798                 }
1799
1800
1801                 memcpy(mntfh->data, data->root.data, mntfh->size);
1802                 if (mntfh->size < sizeof(mntfh->data))
1803                         memset(mntfh->data + mntfh->size, 0,
1804                                sizeof(mntfh->data) - mntfh->size);
1805
1806                 /*
1807                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1808                  * can deal with.
1809                  */
1810                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1811                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1812                 args->rsize             = data->rsize;
1813                 args->wsize             = data->wsize;
1814                 args->timeo             = data->timeo;
1815                 args->retrans           = data->retrans;
1816                 args->acregmin          = data->acregmin;
1817                 args->acregmax          = data->acregmax;
1818                 args->acdirmin          = data->acdirmin;
1819                 args->acdirmax          = data->acdirmax;
1820
1821                 memcpy(sap, &data->addr, sizeof(data->addr));
1822                 args->nfs_server.addrlen = sizeof(data->addr);
1823                 if (!nfs_verify_server_address(sap))
1824                         goto out_no_address;
1825
1826                 if (!(data->flags & NFS_MOUNT_TCP))
1827                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1828                 /* N.B. caller will free nfs_server.hostname in all cases */
1829                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1830                 args->namlen            = data->namlen;
1831                 args->bsize             = data->bsize;
1832
1833                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1834                         args->auth_flavors[0] = data->pseudoflavor;
1835                 if (!args->nfs_server.hostname)
1836                         goto out_nomem;
1837
1838                 if (!(data->flags & NFS_MOUNT_NONLM))
1839                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1840                                          NFS_MOUNT_LOCAL_FCNTL);
1841                 else
1842                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1843                                         NFS_MOUNT_LOCAL_FCNTL);
1844                 /*
1845                  * The legacy version 6 binary mount data from userspace has a
1846                  * field used only to transport selinux information into the
1847                  * the kernel.  To continue to support that functionality we
1848                  * have a touch of selinux knowledge here in the NFS code. The
1849                  * userspace code converted context=blah to just blah so we are
1850                  * converting back to the full string selinux understands.
1851                  */
1852                 if (data->context[0]){
1853 #ifdef CONFIG_SECURITY_SELINUX
1854                         int rc;
1855                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1856                         if (!opts_str)
1857                                 return -ENOMEM;
1858                         strcpy(opts_str, "context=");
1859                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1860                         strcat(opts_str, &data->context[0]);
1861                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1862                         kfree(opts_str);
1863                         if (rc)
1864                                 return rc;
1865 #else
1866                         return -EINVAL;
1867 #endif
1868                 }
1869
1870                 break;
1871         default: {
1872                 int status;
1873
1874                 if (nfs_parse_mount_options((char *)options, args) == 0)
1875                         return -EINVAL;
1876
1877                 if (!nfs_verify_server_address(sap))
1878                         goto out_no_address;
1879
1880                 if (args->version == 4)
1881 #ifdef CONFIG_NFS_V4
1882                         return nfs4_validate_text_mount_data(options,
1883                                                              args, dev_name);
1884 #else
1885                         goto out_v4_not_compiled;
1886 #endif
1887
1888                 nfs_set_port(sap, &args->nfs_server.port, 0);
1889
1890                 nfs_set_mount_transport_protocol(args);
1891
1892                 status = nfs_parse_devname(dev_name,
1893                                            &args->nfs_server.hostname,
1894                                            PAGE_SIZE,
1895                                            &args->nfs_server.export_path,
1896                                            NFS_MAXPATHLEN);
1897                 if (!status)
1898                         status = nfs_try_mount(args, mntfh);
1899
1900                 kfree(args->nfs_server.export_path);
1901                 args->nfs_server.export_path = NULL;
1902
1903                 if (status)
1904                         return status;
1905
1906                 break;
1907                 }
1908         }
1909
1910 #ifndef CONFIG_NFS_V3
1911         if (args->version == 3)
1912                 goto out_v3_not_compiled;
1913 #endif /* !CONFIG_NFS_V3 */
1914
1915         return 0;
1916
1917 out_no_data:
1918         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1919         return -EINVAL;
1920
1921 out_no_v3:
1922         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1923                  data->version);
1924         return -EINVAL;
1925
1926 out_no_sec:
1927         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1928         return -EINVAL;
1929
1930 #ifndef CONFIG_NFS_V3
1931 out_v3_not_compiled:
1932         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1933         return -EPROTONOSUPPORT;
1934 #endif /* !CONFIG_NFS_V3 */
1935
1936 #ifndef CONFIG_NFS_V4
1937 out_v4_not_compiled:
1938         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1939         return -EPROTONOSUPPORT;
1940 #endif /* !CONFIG_NFS_V4 */
1941
1942 out_nomem:
1943         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1944         return -ENOMEM;
1945
1946 out_no_address:
1947         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1948         return -EINVAL;
1949
1950 out_invalid_fh:
1951         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1952         return -EINVAL;
1953 }
1954
1955 static int
1956 nfs_compare_remount_data(struct nfs_server *nfss,
1957                          struct nfs_parsed_mount_data *data)
1958 {
1959         if (data->flags != nfss->flags ||
1960             data->rsize != nfss->rsize ||
1961             data->wsize != nfss->wsize ||
1962             data->retrans != nfss->client->cl_timeout->to_retries ||
1963             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1964             data->acregmin != nfss->acregmin / HZ ||
1965             data->acregmax != nfss->acregmax / HZ ||
1966             data->acdirmin != nfss->acdirmin / HZ ||
1967             data->acdirmax != nfss->acdirmax / HZ ||
1968             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1969             data->nfs_server.port != nfss->port ||
1970             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1971             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1972                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1973                 return -EINVAL;
1974
1975         return 0;
1976 }
1977
1978 static int
1979 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1980 {
1981         int error;
1982         struct nfs_server *nfss = sb->s_fs_info;
1983         struct nfs_parsed_mount_data *data;
1984         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1985         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1986         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1987
1988         /*
1989          * Userspace mount programs that send binary options generally send
1990          * them populated with default values. We have no way to know which
1991          * ones were explicitly specified. Fall back to legacy behavior and
1992          * just return success.
1993          */
1994         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1995             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1996                                            options->version <= 6))))
1997                 return 0;
1998
1999         data = kzalloc(sizeof(*data), GFP_KERNEL);
2000         if (data == NULL)
2001                 return -ENOMEM;
2002
2003         /* fill out struct with values from existing mount */
2004         data->flags = nfss->flags;
2005         data->rsize = nfss->rsize;
2006         data->wsize = nfss->wsize;
2007         data->retrans = nfss->client->cl_timeout->to_retries;
2008         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2009         data->acregmin = nfss->acregmin / HZ;
2010         data->acregmax = nfss->acregmax / HZ;
2011         data->acdirmin = nfss->acdirmin / HZ;
2012         data->acdirmax = nfss->acdirmax / HZ;
2013         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2014         data->nfs_server.port = nfss->port;
2015         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2016         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2017                 data->nfs_server.addrlen);
2018
2019         /* overwrite those values with any that were specified */
2020         error = nfs_parse_mount_options((char *)options, data);
2021         if (error < 0)
2022                 goto out;
2023
2024         /*
2025          * noac is a special case. It implies -o sync, but that's not
2026          * necessarily reflected in the mtab options. do_remount_sb
2027          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2028          * remount options, so we have to explicitly reset it.
2029          */
2030         if (data->flags & NFS_MOUNT_NOAC)
2031                 *flags |= MS_SYNCHRONOUS;
2032
2033         /* compare new mount options with old ones */
2034         error = nfs_compare_remount_data(nfss, data);
2035 out:
2036         kfree(data);
2037         return error;
2038 }
2039
2040 /*
2041  * Initialise the common bits of the superblock
2042  */
2043 static inline void nfs_initialise_sb(struct super_block *sb)
2044 {
2045         struct nfs_server *server = NFS_SB(sb);
2046
2047         sb->s_magic = NFS_SUPER_MAGIC;
2048
2049         /* We probably want something more informative here */
2050         snprintf(sb->s_id, sizeof(sb->s_id),
2051                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2052
2053         if (sb->s_blocksize == 0)
2054                 sb->s_blocksize = nfs_block_bits(server->wsize,
2055                                                  &sb->s_blocksize_bits);
2056
2057         sb->s_bdi = &server->backing_dev_info;
2058
2059         nfs_super_set_maxbytes(sb, server->maxfilesize);
2060 }
2061
2062 /*
2063  * Finish setting up an NFS2/3 superblock
2064  */
2065 static void nfs_fill_super(struct super_block *sb,
2066                            struct nfs_parsed_mount_data *data)
2067 {
2068         struct nfs_server *server = NFS_SB(sb);
2069
2070         sb->s_blocksize_bits = 0;
2071         sb->s_blocksize = 0;
2072         if (data->bsize)
2073                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2074
2075         if (server->nfs_client->rpc_ops->version == 3) {
2076                 /* The VFS shouldn't apply the umask to mode bits. We will do
2077                  * so ourselves when necessary.
2078                  */
2079                 sb->s_flags |= MS_POSIXACL;
2080                 sb->s_time_gran = 1;
2081         }
2082
2083         sb->s_op = &nfs_sops;
2084         nfs_initialise_sb(sb);
2085 }
2086
2087 /*
2088  * Finish setting up a cloned NFS2/3 superblock
2089  */
2090 static void nfs_clone_super(struct super_block *sb,
2091                             const struct super_block *old_sb)
2092 {
2093         struct nfs_server *server = NFS_SB(sb);
2094
2095         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2096         sb->s_blocksize = old_sb->s_blocksize;
2097         sb->s_maxbytes = old_sb->s_maxbytes;
2098
2099         if (server->nfs_client->rpc_ops->version == 3) {
2100                 /* The VFS shouldn't apply the umask to mode bits. We will do
2101                  * so ourselves when necessary.
2102                  */
2103                 sb->s_flags |= MS_POSIXACL;
2104                 sb->s_time_gran = 1;
2105         }
2106
2107         sb->s_op = old_sb->s_op;
2108         nfs_initialise_sb(sb);
2109 }
2110
2111 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2112 {
2113         const struct nfs_server *a = s->s_fs_info;
2114         const struct rpc_clnt *clnt_a = a->client;
2115         const struct rpc_clnt *clnt_b = b->client;
2116
2117         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2118                 goto Ebusy;
2119         if (a->nfs_client != b->nfs_client)
2120                 goto Ebusy;
2121         if (a->flags != b->flags)
2122                 goto Ebusy;
2123         if (a->wsize != b->wsize)
2124                 goto Ebusy;
2125         if (a->rsize != b->rsize)
2126                 goto Ebusy;
2127         if (a->acregmin != b->acregmin)
2128                 goto Ebusy;
2129         if (a->acregmax != b->acregmax)
2130                 goto Ebusy;
2131         if (a->acdirmin != b->acdirmin)
2132                 goto Ebusy;
2133         if (a->acdirmax != b->acdirmax)
2134                 goto Ebusy;
2135         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2136                 goto Ebusy;
2137         return 1;
2138 Ebusy:
2139         return 0;
2140 }
2141
2142 struct nfs_sb_mountdata {
2143         struct nfs_server *server;
2144         int mntflags;
2145 };
2146
2147 static int nfs_set_super(struct super_block *s, void *data)
2148 {
2149         struct nfs_sb_mountdata *sb_mntdata = data;
2150         struct nfs_server *server = sb_mntdata->server;
2151         int ret;
2152
2153         s->s_flags = sb_mntdata->mntflags;
2154         s->s_fs_info = server;
2155         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2156         ret = set_anon_super(s, server);
2157         if (ret == 0)
2158                 server->s_dev = s->s_dev;
2159         return ret;
2160 }
2161
2162 static int nfs_compare_super_address(struct nfs_server *server1,
2163                                      struct nfs_server *server2)
2164 {
2165         struct sockaddr *sap1, *sap2;
2166
2167         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2168         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2169
2170         if (sap1->sa_family != sap2->sa_family)
2171                 return 0;
2172
2173         switch (sap1->sa_family) {
2174         case AF_INET: {
2175                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2176                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2177                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2178                         return 0;
2179                 if (sin1->sin_port != sin2->sin_port)
2180                         return 0;
2181                 break;
2182         }
2183         case AF_INET6: {
2184                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2185                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2186                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2187                         return 0;
2188                 if (sin1->sin6_port != sin2->sin6_port)
2189                         return 0;
2190                 break;
2191         }
2192         default:
2193                 return 0;
2194         }
2195
2196         return 1;
2197 }
2198
2199 static int nfs_compare_super(struct super_block *sb, void *data)
2200 {
2201         struct nfs_sb_mountdata *sb_mntdata = data;
2202         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2203         int mntflags = sb_mntdata->mntflags;
2204
2205         if (!nfs_compare_super_address(old, server))
2206                 return 0;
2207         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2208         if (old->flags & NFS_MOUNT_UNSHARED)
2209                 return 0;
2210         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2211                 return 0;
2212         return nfs_compare_mount_options(sb, server, mntflags);
2213 }
2214
2215 static int nfs_bdi_register(struct nfs_server *server)
2216 {
2217         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2218 }
2219
2220 static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2221         int flags, const char *dev_name, void *raw_data)
2222 {
2223         struct nfs_server *server = NULL;
2224         struct super_block *s;
2225         struct nfs_parsed_mount_data *data;
2226         struct nfs_fh *mntfh;
2227         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2228         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2229         struct nfs_sb_mountdata sb_mntdata = {
2230                 .mntflags = flags,
2231         };
2232         int error;
2233
2234         data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
2235         mntfh = nfs_alloc_fhandle();
2236         if (data == NULL || mntfh == NULL)
2237                 goto out;
2238
2239         /* Validate the mount data */
2240         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2241         if (error < 0) {
2242                 mntroot = ERR_PTR(error);
2243                 goto out;
2244         }
2245
2246 #ifdef CONFIG_NFS_V4
2247         if (data->version == 4) {
2248                 mntroot = nfs4_try_mount(flags, dev_name, data);
2249                 goto out;
2250         }
2251 #endif  /* CONFIG_NFS_V4 */
2252
2253         /* Get a volume representation */
2254         server = nfs_create_server(data, mntfh);
2255         if (IS_ERR(server)) {
2256                 mntroot = ERR_CAST(server);
2257                 goto out;
2258         }
2259         sb_mntdata.server = server;
2260
2261         if (server->flags & NFS_MOUNT_UNSHARED)
2262                 compare_super = NULL;
2263
2264         /* -o noac implies -o sync */
2265         if (server->flags & NFS_MOUNT_NOAC)
2266                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2267
2268         /* Get a superblock - note that we may end up sharing one that already exists */
2269         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2270         if (IS_ERR(s)) {
2271                 mntroot = ERR_CAST(s);
2272                 goto out_err_nosb;
2273         }
2274
2275         if (s->s_fs_info != server) {
2276                 nfs_free_server(server);
2277                 server = NULL;
2278         } else {
2279                 error = nfs_bdi_register(server);
2280                 if (error) {
2281                         mntroot = ERR_PTR(error);
2282                         goto error_splat_bdi;
2283                 }
2284         }
2285
2286         if (!s->s_root) {
2287                 /* initial superblock/root creation */
2288                 nfs_fill_super(s, data);
2289                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2290         }
2291
2292         mntroot = nfs_get_root(s, mntfh, dev_name);
2293         if (IS_ERR(mntroot))
2294                 goto error_splat_super;
2295
2296         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2297         if (error)
2298                 goto error_splat_root;
2299
2300         s->s_flags |= MS_ACTIVE;
2301
2302 out:
2303         nfs_free_parsed_mount_data(data);
2304         nfs_free_fhandle(mntfh);
2305         return mntroot;
2306
2307 out_err_nosb:
2308         nfs_free_server(server);
2309         goto out;
2310
2311 error_splat_root:
2312         dput(mntroot);
2313         mntroot = ERR_PTR(error);
2314 error_splat_super:
2315         if (server && !s->s_root)
2316                 bdi_unregister(&server->backing_dev_info);
2317 error_splat_bdi:
2318         deactivate_locked_super(s);
2319         goto out;
2320 }
2321
2322 /*
2323  * Ensure that we unregister the bdi before kill_anon_super
2324  * releases the device name
2325  */
2326 static void nfs_put_super(struct super_block *s)
2327 {
2328         struct nfs_server *server = NFS_SB(s);
2329
2330         bdi_unregister(&server->backing_dev_info);
2331 }
2332
2333 /*
2334  * Destroy an NFS2/3 superblock
2335  */
2336 static void nfs_kill_super(struct super_block *s)
2337 {
2338         struct nfs_server *server = NFS_SB(s);
2339
2340         kill_anon_super(s);
2341         nfs_fscache_release_super_cookie(s);
2342         nfs_free_server(server);
2343 }
2344
2345 /*
2346  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2347  */
2348 static struct dentry *
2349 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2350                 const char *dev_name, void *raw_data)
2351 {
2352         struct nfs_clone_mount *data = raw_data;
2353         struct super_block *s;
2354         struct nfs_server *server;
2355         struct dentry *mntroot;
2356         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2357         struct nfs_sb_mountdata sb_mntdata = {
2358                 .mntflags = flags,
2359         };
2360         int error;
2361
2362         dprintk("--> nfs_xdev_mount()\n");
2363
2364         /* create a new volume representation */
2365         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2366         if (IS_ERR(server)) {
2367                 error = PTR_ERR(server);
2368                 goto out_err_noserver;
2369         }
2370         sb_mntdata.server = server;
2371
2372         if (server->flags & NFS_MOUNT_UNSHARED)
2373                 compare_super = NULL;
2374
2375         /* -o noac implies -o sync */
2376         if (server->flags & NFS_MOUNT_NOAC)
2377                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2378
2379         /* Get a superblock - note that we may end up sharing one that already exists */
2380         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2381         if (IS_ERR(s)) {
2382                 error = PTR_ERR(s);
2383                 goto out_err_nosb;
2384         }
2385
2386         if (s->s_fs_info != server) {
2387                 nfs_free_server(server);
2388                 server = NULL;
2389         } else {
2390                 error = nfs_bdi_register(server);
2391                 if (error)
2392                         goto error_splat_bdi;
2393         }
2394
2395         if (!s->s_root) {
2396                 /* initial superblock/root creation */
2397                 nfs_clone_super(s, data->sb);
2398                 nfs_fscache_get_super_cookie(s, NULL, data);
2399         }
2400
2401         mntroot = nfs_get_root(s, data->fh, dev_name);
2402         if (IS_ERR(mntroot)) {
2403                 error = PTR_ERR(mntroot);
2404                 goto error_splat_super;
2405         }
2406         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2407                 dput(mntroot);
2408                 error = -ESTALE;
2409                 goto error_splat_super;
2410         }
2411
2412         s->s_flags |= MS_ACTIVE;
2413
2414         /* clone any lsm security options from the parent to the new sb */
2415         security_sb_clone_mnt_opts(data->sb, s);
2416
2417         dprintk("<-- nfs_xdev_mount() = 0\n");
2418         return mntroot;
2419
2420 out_err_nosb:
2421         nfs_free_server(server);
2422 out_err_noserver:
2423         dprintk("<-- nfs_xdev_mount() = %d [error]\n", error);
2424         return ERR_PTR(error);
2425
2426 error_splat_super:
2427         if (server && !s->s_root)
2428                 bdi_unregister(&server->backing_dev_info);
2429 error_splat_bdi:
2430         deactivate_locked_super(s);
2431         dprintk("<-- nfs_xdev_mount() = %d [splat]\n", error);
2432         return ERR_PTR(error);
2433 }
2434
2435 #ifdef CONFIG_NFS_V4
2436
2437 /*
2438  * Finish setting up a cloned NFS4 superblock
2439  */
2440 static void nfs4_clone_super(struct super_block *sb,
2441                             const struct super_block *old_sb)
2442 {
2443         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2444         sb->s_blocksize = old_sb->s_blocksize;
2445         sb->s_maxbytes = old_sb->s_maxbytes;
2446         sb->s_time_gran = 1;
2447         sb->s_op = old_sb->s_op;
2448         /*
2449          * The VFS shouldn't apply the umask to mode bits. We will do
2450          * so ourselves when necessary.
2451          */
2452         sb->s_flags  |= MS_POSIXACL;
2453         sb->s_xattr  = old_sb->s_xattr;
2454         nfs_initialise_sb(sb);
2455 }
2456
2457 /*
2458  * Set up an NFS4 superblock
2459  */
2460 static void nfs4_fill_super(struct super_block *sb)
2461 {
2462         sb->s_time_gran = 1;
2463         sb->s_op = &nfs4_sops;
2464         /*
2465          * The VFS shouldn't apply the umask to mode bits. We will do
2466          * so ourselves when necessary.
2467          */
2468         sb->s_flags  |= MS_POSIXACL;
2469         sb->s_xattr = nfs4_xattr_handlers;
2470         nfs_initialise_sb(sb);
2471 }
2472
2473 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2474 {
2475         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2476                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2477 }
2478
2479 static int nfs4_validate_text_mount_data(void *options,
2480                                          struct nfs_parsed_mount_data *args,
2481                                          const char *dev_name)
2482 {
2483         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2484
2485         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2486
2487         nfs_validate_transport_protocol(args);
2488
2489         nfs4_validate_mount_flags(args);
2490
2491         if (args->version != 4) {
2492                 dfprintk(MOUNT,
2493                          "NFS4: Illegal mount version\n");
2494                 return -EINVAL;
2495         }
2496
2497         if (args->auth_flavor_len > 1) {
2498                 dfprintk(MOUNT,
2499                          "NFS4: Too many RPC auth flavours specified\n");
2500                 return -EINVAL;
2501         }
2502
2503         if (args->client_address == NULL) {
2504                 dfprintk(MOUNT,
2505                          "NFS4: mount program didn't pass callback address\n");
2506                 return -EINVAL;
2507         }
2508
2509         return nfs_parse_devname(dev_name,
2510                                    &args->nfs_server.hostname,
2511                                    NFS4_MAXNAMLEN,
2512                                    &args->nfs_server.export_path,
2513                                    NFS4_MAXPATHLEN);
2514 }
2515
2516 /*
2517  * Validate NFSv4 mount options
2518  */
2519 static int nfs4_validate_mount_data(void *options,
2520                                     struct nfs_parsed_mount_data *args,
2521                                     const char *dev_name)
2522 {
2523         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2524         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2525         char *c;
2526
2527         if (data == NULL)
2528                 goto out_no_data;
2529
2530         switch (data->version) {
2531         case 1:
2532                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2533                         goto out_no_address;
2534                 if (data->host_addrlen == 0)
2535                         goto out_no_address;
2536                 args->nfs_server.addrlen = data->host_addrlen;
2537                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2538                         return -EFAULT;
2539                 if (!nfs_verify_server_address(sap))
2540                         goto out_no_address;
2541
2542                 if (data->auth_flavourlen) {
2543                         if (data->auth_flavourlen > 1)
2544                                 goto out_inval_auth;
2545                         if (copy_from_user(&args->auth_flavors[0],
2546                                            data->auth_flavours,
2547                                            sizeof(args->auth_flavors[0])))
2548                                 return -EFAULT;
2549                 }
2550
2551                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2552                 if (IS_ERR(c))
2553                         return PTR_ERR(c);
2554                 args->nfs_server.hostname = c;
2555
2556                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2557                 if (IS_ERR(c))
2558                         return PTR_ERR(c);
2559                 args->nfs_server.export_path = c;
2560                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2561
2562                 c = strndup_user(data->client_addr.data, 16);
2563                 if (IS_ERR(c))
2564                         return PTR_ERR(c);
2565                 args->client_address = c;
2566
2567                 /*
2568                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2569                  * can deal with.
2570                  */
2571
2572                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2573                 args->rsize     = data->rsize;
2574                 args->wsize     = data->wsize;
2575                 args->timeo     = data->timeo;
2576                 args->retrans   = data->retrans;
2577                 args->acregmin  = data->acregmin;
2578                 args->acregmax  = data->acregmax;
2579                 args->acdirmin  = data->acdirmin;
2580                 args->acdirmax  = data->acdirmax;
2581                 args->nfs_server.protocol = data->proto;
2582                 nfs_validate_transport_protocol(args);
2583
2584                 break;
2585         default:
2586                 if (nfs_parse_mount_options((char *)options, args) == 0)
2587                         return -EINVAL;
2588
2589                 if (!nfs_verify_server_address(sap))
2590                         return -EINVAL;
2591
2592                 return nfs4_validate_text_mount_data(options, args, dev_name);
2593         }
2594
2595         return 0;
2596
2597 out_no_data:
2598         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2599         return -EINVAL;
2600
2601 out_inval_auth:
2602         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2603                  data->auth_flavourlen);
2604         return -EINVAL;
2605
2606 out_no_address:
2607         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2608         return -EINVAL;
2609 }
2610
2611 /*
2612  * Get the superblock for the NFS4 root partition
2613  */
2614 static struct dentry *
2615 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
2616                   const char *dev_name, void *raw_data)
2617 {
2618         struct nfs_parsed_mount_data *data = raw_data;
2619         struct super_block *s;
2620         struct nfs_server *server;
2621         struct nfs_fh *mntfh;
2622         struct dentry *mntroot;
2623         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2624         struct nfs_sb_mountdata sb_mntdata = {
2625                 .mntflags = flags,
2626         };
2627         int error = -ENOMEM;
2628
2629         mntfh = nfs_alloc_fhandle();
2630         if (data == NULL || mntfh == NULL)
2631                 goto out;
2632
2633         /* Get a volume representation */
2634         server = nfs4_create_server(data, mntfh);
2635         if (IS_ERR(server)) {
2636                 error = PTR_ERR(server);
2637                 goto out;
2638         }
2639         sb_mntdata.server = server;
2640
2641         if (server->flags & NFS4_MOUNT_UNSHARED)
2642                 compare_super = NULL;
2643
2644         /* -o noac implies -o sync */
2645         if (server->flags & NFS_MOUNT_NOAC)
2646                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2647
2648         /* Get a superblock - note that we may end up sharing one that already exists */
2649         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2650         if (IS_ERR(s)) {
2651                 error = PTR_ERR(s);
2652                 goto out_free;
2653         }
2654
2655         if (s->s_fs_info != server) {
2656                 nfs_free_server(server);
2657                 server = NULL;
2658         } else {
2659                 error = nfs_bdi_register(server);
2660                 if (error)
2661                         goto error_splat_bdi;
2662         }
2663
2664         if (!s->s_root) {
2665                 /* initial superblock/root creation */
2666                 nfs4_fill_super(s);
2667                 nfs_fscache_get_super_cookie(
2668                         s, data ? data->fscache_uniq : NULL, NULL);
2669         }
2670
2671         mntroot = nfs4_get_root(s, mntfh, dev_name);
2672         if (IS_ERR(mntroot)) {
2673                 error = PTR_ERR(mntroot);
2674                 goto error_splat_super;
2675         }
2676
2677         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2678         if (error)
2679                 goto error_splat_root;
2680
2681         s->s_flags |= MS_ACTIVE;
2682
2683         nfs_free_fhandle(mntfh);
2684         return mntroot;
2685
2686 out:
2687         nfs_free_fhandle(mntfh);
2688         return ERR_PTR(error);
2689
2690 out_free:
2691         nfs_free_server(server);
2692         goto out;
2693
2694 error_splat_root:
2695         dput(mntroot);
2696 error_splat_super:
2697         if (server && !s->s_root)
2698                 bdi_unregister(&server->backing_dev_info);
2699 error_splat_bdi:
2700         deactivate_locked_super(s);
2701         goto out;
2702 }
2703
2704 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2705                 int flags, void *data, const char *hostname)
2706 {
2707         struct vfsmount *root_mnt;
2708         char *root_devname;
2709         size_t len;
2710
2711         len = strlen(hostname) + 3;
2712         root_devname = kmalloc(len, GFP_KERNEL);
2713         if (root_devname == NULL)
2714                 return ERR_PTR(-ENOMEM);
2715         snprintf(root_devname, len, "%s:/", hostname);
2716         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2717         kfree(root_devname);
2718         return root_mnt;
2719 }
2720
2721 struct nfs_referral_count {
2722         struct list_head list;
2723         const struct task_struct *task;
2724         unsigned int referral_count;
2725 };
2726
2727 static LIST_HEAD(nfs_referral_count_list);
2728 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2729
2730 static struct nfs_referral_count *nfs_find_referral_count(void)
2731 {
2732         struct nfs_referral_count *p;
2733
2734         list_for_each_entry(p, &nfs_referral_count_list, list) {
2735                 if (p->task == current)
2736                         return p;
2737         }
2738         return NULL;
2739 }
2740
2741 #define NFS_MAX_NESTED_REFERRALS 2
2742
2743 static int nfs_referral_loop_protect(void)
2744 {
2745         struct nfs_referral_count *p, *new;
2746         int ret = -ENOMEM;
2747
2748         new = kmalloc(sizeof(*new), GFP_KERNEL);
2749         if (!new)
2750                 goto out;
2751         new->task = current;
2752         new->referral_count = 1;
2753
2754         ret = 0;
2755         spin_lock(&nfs_referral_count_list_lock);
2756         p = nfs_find_referral_count();
2757         if (p != NULL) {
2758                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2759                         ret = -ELOOP;
2760                 else
2761                         p->referral_count++;
2762         } else {
2763                 list_add(&new->list, &nfs_referral_count_list);
2764                 new = NULL;
2765         }
2766         spin_unlock(&nfs_referral_count_list_lock);
2767         kfree(new);
2768 out:
2769         return ret;
2770 }
2771
2772 static void nfs_referral_loop_unprotect(void)
2773 {
2774         struct nfs_referral_count *p;
2775
2776         spin_lock(&nfs_referral_count_list_lock);
2777         p = nfs_find_referral_count();
2778         p->referral_count--;
2779         if (p->referral_count == 0)
2780                 list_del(&p->list);
2781         else
2782                 p = NULL;
2783         spin_unlock(&nfs_referral_count_list_lock);
2784         kfree(p);
2785 }
2786
2787 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
2788                 const char *export_path)
2789 {
2790         struct dentry *dentry;
2791         int ret = nfs_referral_loop_protect();
2792
2793         if (ret) {
2794                 mntput(root_mnt);
2795                 return ERR_PTR(ret);
2796         }
2797
2798         dentry = mount_subtree(root_mnt, export_path);
2799         nfs_referral_loop_unprotect();
2800
2801         return dentry;
2802 }
2803
2804 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
2805                          struct nfs_parsed_mount_data *data)
2806 {
2807         char *export_path;
2808         struct vfsmount *root_mnt;
2809         struct dentry *res;
2810
2811         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2812
2813         export_path = data->nfs_server.export_path;
2814         data->nfs_server.export_path = "/";
2815         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2816                         data->nfs_server.hostname);
2817         data->nfs_server.export_path = export_path;
2818
2819         res = ERR_CAST(root_mnt);
2820         if (!IS_ERR(root_mnt))
2821                 res = nfs_follow_remote_path(root_mnt, export_path);
2822
2823         dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
2824                         IS_ERR(res) ? PTR_ERR(res) : 0,
2825                         IS_ERR(res) ? " [error]" : "");
2826         return res;
2827 }
2828
2829 /*
2830  * Get the superblock for an NFS4 mountpoint
2831  */
2832 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
2833         int flags, const char *dev_name, void *raw_data)
2834 {
2835         struct nfs_parsed_mount_data *data;
2836         int error = -ENOMEM;
2837         struct dentry *res = ERR_PTR(-ENOMEM);
2838
2839         data = nfs_alloc_parsed_mount_data(4);
2840         if (data == NULL)
2841                 goto out;
2842
2843         /* Validate the mount data */
2844         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2845         if (error < 0) {
2846                 res = ERR_PTR(error);
2847                 goto out;
2848         }
2849
2850         res = nfs4_try_mount(flags, dev_name, data);
2851         if (IS_ERR(res))
2852                 error = PTR_ERR(res);
2853
2854 out:
2855         nfs_free_parsed_mount_data(data);
2856         dprintk("<-- nfs4_mount() = %d%s\n", error,
2857                         error != 0 ? " [error]" : "");
2858         return res;
2859 }
2860
2861 static void nfs4_kill_super(struct super_block *sb)
2862 {
2863         struct nfs_server *server = NFS_SB(sb);
2864
2865         dprintk("--> %s\n", __func__);
2866         nfs_super_return_all_delegations(sb);
2867         kill_anon_super(sb);
2868         nfs_fscache_release_super_cookie(sb);
2869         nfs_free_server(server);
2870         dprintk("<-- %s\n", __func__);
2871 }
2872
2873 /*
2874  * Clone an NFS4 server record on xdev traversal (FSID-change)
2875  */
2876 static struct dentry *
2877 nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
2878                  const char *dev_name, void *raw_data)
2879 {
2880         struct nfs_clone_mount *data = raw_data;
2881         struct super_block *s;
2882         struct nfs_server *server;
2883         struct dentry *mntroot;
2884         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2885         struct nfs_sb_mountdata sb_mntdata = {
2886                 .mntflags = flags,
2887         };
2888         int error;
2889
2890         dprintk("--> nfs4_xdev_mount()\n");
2891
2892         /* create a new volume representation */
2893         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2894         if (IS_ERR(server)) {
2895                 error = PTR_ERR(server);
2896                 goto out_err_noserver;
2897         }
2898         sb_mntdata.server = server;
2899
2900         if (server->flags & NFS4_MOUNT_UNSHARED)
2901                 compare_super = NULL;
2902
2903         /* -o noac implies -o sync */
2904         if (server->flags & NFS_MOUNT_NOAC)
2905                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2906
2907         /* Get a superblock - note that we may end up sharing one that already exists */
2908         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2909         if (IS_ERR(s)) {
2910                 error = PTR_ERR(s);
2911                 goto out_err_nosb;
2912         }
2913
2914         if (s->s_fs_info != server) {
2915                 nfs_free_server(server);
2916                 server = NULL;
2917         } else {
2918                 error = nfs_bdi_register(server);
2919                 if (error)
2920                         goto error_splat_bdi;
2921         }
2922
2923         if (!s->s_root) {
2924                 /* initial superblock/root creation */
2925                 nfs4_clone_super(s, data->sb);
2926                 nfs_fscache_get_super_cookie(s, NULL, data);
2927         }
2928
2929         mntroot = nfs4_get_root(s, data->fh, dev_name);
2930         if (IS_ERR(mntroot)) {
2931                 error = PTR_ERR(mntroot);
2932                 goto error_splat_super;
2933         }
2934         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2935                 dput(mntroot);
2936                 error = -ESTALE;
2937                 goto error_splat_super;
2938         }
2939
2940         s->s_flags |= MS_ACTIVE;
2941
2942         security_sb_clone_mnt_opts(data->sb, s);
2943
2944         dprintk("<-- nfs4_xdev_mount() = 0\n");
2945         return mntroot;
2946
2947 out_err_nosb:
2948         nfs_free_server(server);
2949 out_err_noserver:
2950         dprintk("<-- nfs4_xdev_mount() = %d [error]\n", error);
2951         return ERR_PTR(error);
2952
2953 error_splat_super:
2954         if (server && !s->s_root)
2955                 bdi_unregister(&server->backing_dev_info);
2956 error_splat_bdi:
2957         deactivate_locked_super(s);
2958         dprintk("<-- nfs4_xdev_mount() = %d [splat]\n", error);
2959         return ERR_PTR(error);
2960 }
2961
2962 static struct dentry *
2963 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
2964                            const char *dev_name, void *raw_data)
2965 {
2966         struct nfs_clone_mount *data = raw_data;
2967         struct super_block *s;
2968         struct nfs_server *server;
2969         struct dentry *mntroot;
2970         struct nfs_fh *mntfh;
2971         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2972         struct nfs_sb_mountdata sb_mntdata = {
2973                 .mntflags = flags,
2974         };
2975         int error = -ENOMEM;
2976
2977         dprintk("--> nfs4_referral_get_sb()\n");
2978
2979         mntfh = nfs_alloc_fhandle();
2980         if (mntfh == NULL)
2981                 goto out_err_nofh;
2982
2983         /* create a new volume representation */
2984         server = nfs4_create_referral_server(data, mntfh);
2985         if (IS_ERR(server)) {
2986                 error = PTR_ERR(server);
2987                 goto out_err_noserver;
2988         }
2989         sb_mntdata.server = server;
2990
2991         if (server->flags & NFS4_MOUNT_UNSHARED)
2992                 compare_super = NULL;
2993
2994         /* -o noac implies -o sync */
2995         if (server->flags & NFS_MOUNT_NOAC)
2996                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2997
2998         /* Get a superblock - note that we may end up sharing one that already exists */
2999         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
3000         if (IS_ERR(s)) {
3001                 error = PTR_ERR(s);
3002                 goto out_err_nosb;
3003         }
3004
3005         if (s->s_fs_info != server) {
3006                 nfs_free_server(server);
3007                 server = NULL;
3008         } else {
3009                 error = nfs_bdi_register(server);
3010                 if (error)
3011                         goto error_splat_bdi;
3012         }
3013
3014         if (!s->s_root) {
3015                 /* initial superblock/root creation */
3016                 nfs4_fill_super(s);
3017                 nfs_fscache_get_super_cookie(s, NULL, data);
3018         }
3019
3020         mntroot = nfs4_get_root(s, mntfh, dev_name);
3021         if (IS_ERR(mntroot)) {
3022                 error = PTR_ERR(mntroot);
3023                 goto error_splat_super;
3024         }
3025         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3026                 dput(mntroot);
3027                 error = -ESTALE;
3028                 goto error_splat_super;
3029         }
3030
3031         s->s_flags |= MS_ACTIVE;
3032
3033         security_sb_clone_mnt_opts(data->sb, s);
3034
3035         nfs_free_fhandle(mntfh);
3036         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3037         return mntroot;
3038
3039 out_err_nosb:
3040         nfs_free_server(server);
3041 out_err_noserver:
3042         nfs_free_fhandle(mntfh);
3043 out_err_nofh:
3044         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3045         return ERR_PTR(error);
3046
3047 error_splat_super:
3048         if (server && !s->s_root)
3049                 bdi_unregister(&server->backing_dev_info);
3050 error_splat_bdi:
3051         deactivate_locked_super(s);
3052         nfs_free_fhandle(mntfh);
3053         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3054         return ERR_PTR(error);
3055 }
3056
3057 /*
3058  * Create an NFS4 server record on referral traversal
3059  */
3060 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
3061                 int flags, const char *dev_name, void *raw_data)
3062 {
3063         struct nfs_clone_mount *data = raw_data;
3064         char *export_path;
3065         struct vfsmount *root_mnt;
3066         struct dentry *res;
3067
3068         dprintk("--> nfs4_referral_mount()\n");
3069
3070         export_path = data->mnt_path;
3071         data->mnt_path = "/";
3072
3073         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3074                         flags, data, data->hostname);
3075         data->mnt_path = export_path;
3076
3077         res = ERR_CAST(root_mnt);
3078         if (!IS_ERR(root_mnt))
3079                 res = nfs_follow_remote_path(root_mnt, export_path);
3080         dprintk("<-- nfs4_referral_mount() = %ld%s\n",
3081                         IS_ERR(res) ? PTR_ERR(res) : 0,
3082                         IS_ERR(res) ? " [error]" : "");
3083         return res;
3084 }
3085
3086 #endif /* CONFIG_NFS_V4 */