Merge branch 'nfs-for-3.3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
[~shefty/rdma-dev.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/namei.h>
45 #include <linux/nfs_idmap.h>
46 #include <linux/vfs.h>
47 #include <linux/inet.h>
48 #include <linux/in6.h>
49 #include <linux/slab.h>
50 #include <net/ipv6.h>
51 #include <linux/netdevice.h>
52 #include <linux/nfs_xdr.h>
53 #include <linux/magic.h>
54 #include <linux/parser.h>
55
56 #include <asm/system.h>
57 #include <asm/uaccess.h>
58
59 #include "nfs4_fs.h"
60 #include "callback.h"
61 #include "delegation.h"
62 #include "iostat.h"
63 #include "internal.h"
64 #include "fscache.h"
65 #include "pnfs.h"
66
67 #define NFSDBG_FACILITY         NFSDBG_VFS
68
69 #ifdef CONFIG_NFS_V3
70 #define NFS_DEFAULT_VERSION 3
71 #else
72 #define NFS_DEFAULT_VERSION 2
73 #endif
74
75 enum {
76         /* Mount options that take no arguments */
77         Opt_soft, Opt_hard,
78         Opt_posix, Opt_noposix,
79         Opt_cto, Opt_nocto,
80         Opt_ac, Opt_noac,
81         Opt_lock, Opt_nolock,
82         Opt_v2, Opt_v3, Opt_v4,
83         Opt_udp, Opt_tcp, Opt_rdma,
84         Opt_acl, Opt_noacl,
85         Opt_rdirplus, Opt_nordirplus,
86         Opt_sharecache, Opt_nosharecache,
87         Opt_resvport, Opt_noresvport,
88         Opt_fscache, Opt_nofscache,
89
90         /* Mount options that take integer arguments */
91         Opt_port,
92         Opt_rsize, Opt_wsize, Opt_bsize,
93         Opt_timeo, Opt_retrans,
94         Opt_acregmin, Opt_acregmax,
95         Opt_acdirmin, Opt_acdirmax,
96         Opt_actimeo,
97         Opt_namelen,
98         Opt_mountport,
99         Opt_mountvers,
100         Opt_nfsvers,
101         Opt_minorversion,
102
103         /* Mount options that take string arguments */
104         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
105         Opt_addr, Opt_mountaddr, Opt_clientaddr,
106         Opt_lookupcache,
107         Opt_fscache_uniq,
108         Opt_local_lock,
109
110         /* Special mount options */
111         Opt_userspace, Opt_deprecated, Opt_sloppy,
112
113         Opt_err
114 };
115
116 static const match_table_t nfs_mount_option_tokens = {
117         { Opt_userspace, "bg" },
118         { Opt_userspace, "fg" },
119         { Opt_userspace, "retry=%s" },
120
121         { Opt_sloppy, "sloppy" },
122
123         { Opt_soft, "soft" },
124         { Opt_hard, "hard" },
125         { Opt_deprecated, "intr" },
126         { Opt_deprecated, "nointr" },
127         { Opt_posix, "posix" },
128         { Opt_noposix, "noposix" },
129         { Opt_cto, "cto" },
130         { Opt_nocto, "nocto" },
131         { Opt_ac, "ac" },
132         { Opt_noac, "noac" },
133         { Opt_lock, "lock" },
134         { Opt_nolock, "nolock" },
135         { Opt_v2, "v2" },
136         { Opt_v3, "v3" },
137         { Opt_v4, "v4" },
138         { Opt_udp, "udp" },
139         { Opt_tcp, "tcp" },
140         { Opt_rdma, "rdma" },
141         { Opt_acl, "acl" },
142         { Opt_noacl, "noacl" },
143         { Opt_rdirplus, "rdirplus" },
144         { Opt_nordirplus, "nordirplus" },
145         { Opt_sharecache, "sharecache" },
146         { Opt_nosharecache, "nosharecache" },
147         { Opt_resvport, "resvport" },
148         { Opt_noresvport, "noresvport" },
149         { Opt_fscache, "fsc" },
150         { Opt_nofscache, "nofsc" },
151
152         { Opt_port, "port=%s" },
153         { Opt_rsize, "rsize=%s" },
154         { Opt_wsize, "wsize=%s" },
155         { Opt_bsize, "bsize=%s" },
156         { Opt_timeo, "timeo=%s" },
157         { Opt_retrans, "retrans=%s" },
158         { Opt_acregmin, "acregmin=%s" },
159         { Opt_acregmax, "acregmax=%s" },
160         { Opt_acdirmin, "acdirmin=%s" },
161         { Opt_acdirmax, "acdirmax=%s" },
162         { Opt_actimeo, "actimeo=%s" },
163         { Opt_namelen, "namlen=%s" },
164         { Opt_mountport, "mountport=%s" },
165         { Opt_mountvers, "mountvers=%s" },
166         { Opt_nfsvers, "nfsvers=%s" },
167         { Opt_nfsvers, "vers=%s" },
168         { Opt_minorversion, "minorversion=%s" },
169
170         { Opt_sec, "sec=%s" },
171         { Opt_proto, "proto=%s" },
172         { Opt_mountproto, "mountproto=%s" },
173         { Opt_addr, "addr=%s" },
174         { Opt_clientaddr, "clientaddr=%s" },
175         { Opt_mounthost, "mounthost=%s" },
176         { Opt_mountaddr, "mountaddr=%s" },
177
178         { Opt_lookupcache, "lookupcache=%s" },
179         { Opt_fscache_uniq, "fsc=%s" },
180         { Opt_local_lock, "local_lock=%s" },
181
182         { Opt_err, NULL }
183 };
184
185 enum {
186         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
187
188         Opt_xprt_err
189 };
190
191 static const match_table_t nfs_xprt_protocol_tokens = {
192         { Opt_xprt_udp, "udp" },
193         { Opt_xprt_udp6, "udp6" },
194         { Opt_xprt_tcp, "tcp" },
195         { Opt_xprt_tcp6, "tcp6" },
196         { Opt_xprt_rdma, "rdma" },
197
198         { Opt_xprt_err, NULL }
199 };
200
201 enum {
202         Opt_sec_none, Opt_sec_sys,
203         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
204         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
205         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
206
207         Opt_sec_err
208 };
209
210 static const match_table_t nfs_secflavor_tokens = {
211         { Opt_sec_none, "none" },
212         { Opt_sec_none, "null" },
213         { Opt_sec_sys, "sys" },
214
215         { Opt_sec_krb5, "krb5" },
216         { Opt_sec_krb5i, "krb5i" },
217         { Opt_sec_krb5p, "krb5p" },
218
219         { Opt_sec_lkey, "lkey" },
220         { Opt_sec_lkeyi, "lkeyi" },
221         { Opt_sec_lkeyp, "lkeyp" },
222
223         { Opt_sec_spkm, "spkm3" },
224         { Opt_sec_spkmi, "spkm3i" },
225         { Opt_sec_spkmp, "spkm3p" },
226
227         { Opt_sec_err, NULL }
228 };
229
230 enum {
231         Opt_lookupcache_all, Opt_lookupcache_positive,
232         Opt_lookupcache_none,
233
234         Opt_lookupcache_err
235 };
236
237 static match_table_t nfs_lookupcache_tokens = {
238         { Opt_lookupcache_all, "all" },
239         { Opt_lookupcache_positive, "pos" },
240         { Opt_lookupcache_positive, "positive" },
241         { Opt_lookupcache_none, "none" },
242
243         { Opt_lookupcache_err, NULL }
244 };
245
246 enum {
247         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
248         Opt_local_lock_none,
249
250         Opt_local_lock_err
251 };
252
253 static match_table_t nfs_local_lock_tokens = {
254         { Opt_local_lock_all, "all" },
255         { Opt_local_lock_flock, "flock" },
256         { Opt_local_lock_posix, "posix" },
257         { Opt_local_lock_none, "none" },
258
259         { Opt_local_lock_err, NULL }
260 };
261
262
263 static void nfs_umount_begin(struct super_block *);
264 static int  nfs_statfs(struct dentry *, struct kstatfs *);
265 static int  nfs_show_options(struct seq_file *, struct dentry *);
266 static int  nfs_show_devname(struct seq_file *, struct dentry *);
267 static int  nfs_show_path(struct seq_file *, struct dentry *);
268 static int  nfs_show_stats(struct seq_file *, struct dentry *);
269 static struct dentry *nfs_fs_mount(struct file_system_type *,
270                 int, const char *, void *);
271 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
272                 int flags, const char *dev_name, void *raw_data);
273 static void nfs_put_super(struct super_block *);
274 static void nfs_kill_super(struct super_block *);
275 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
276
277 static struct file_system_type nfs_fs_type = {
278         .owner          = THIS_MODULE,
279         .name           = "nfs",
280         .mount          = nfs_fs_mount,
281         .kill_sb        = nfs_kill_super,
282         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
283 };
284
285 struct file_system_type nfs_xdev_fs_type = {
286         .owner          = THIS_MODULE,
287         .name           = "nfs",
288         .mount          = nfs_xdev_mount,
289         .kill_sb        = nfs_kill_super,
290         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
291 };
292
293 static const struct super_operations nfs_sops = {
294         .alloc_inode    = nfs_alloc_inode,
295         .destroy_inode  = nfs_destroy_inode,
296         .write_inode    = nfs_write_inode,
297         .put_super      = nfs_put_super,
298         .statfs         = nfs_statfs,
299         .evict_inode    = nfs_evict_inode,
300         .umount_begin   = nfs_umount_begin,
301         .show_options   = nfs_show_options,
302         .show_devname   = nfs_show_devname,
303         .show_path      = nfs_show_path,
304         .show_stats     = nfs_show_stats,
305         .remount_fs     = nfs_remount,
306 };
307
308 #ifdef CONFIG_NFS_V4
309 static int nfs4_validate_text_mount_data(void *options,
310         struct nfs_parsed_mount_data *args, const char *dev_name);
311 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
312         struct nfs_parsed_mount_data *data);
313 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
314         int flags, const char *dev_name, void *raw_data);
315 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
316         int flags, const char *dev_name, void *raw_data);
317 static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
318         int flags, const char *dev_name, void *raw_data);
319 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
320         int flags, const char *dev_name, void *raw_data);
321 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
322         int flags, const char *dev_name, void *raw_data);
323 static void nfs4_kill_super(struct super_block *sb);
324
325 static struct file_system_type nfs4_fs_type = {
326         .owner          = THIS_MODULE,
327         .name           = "nfs4",
328         .mount          = nfs4_mount,
329         .kill_sb        = nfs4_kill_super,
330         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
331 };
332
333 static struct file_system_type nfs4_remote_fs_type = {
334         .owner          = THIS_MODULE,
335         .name           = "nfs4",
336         .mount          = nfs4_remote_mount,
337         .kill_sb        = nfs4_kill_super,
338         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
339 };
340
341 struct file_system_type nfs4_xdev_fs_type = {
342         .owner          = THIS_MODULE,
343         .name           = "nfs4",
344         .mount          = nfs4_xdev_mount,
345         .kill_sb        = nfs4_kill_super,
346         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
347 };
348
349 static struct file_system_type nfs4_remote_referral_fs_type = {
350         .owner          = THIS_MODULE,
351         .name           = "nfs4",
352         .mount          = nfs4_remote_referral_mount,
353         .kill_sb        = nfs4_kill_super,
354         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
355 };
356
357 struct file_system_type nfs4_referral_fs_type = {
358         .owner          = THIS_MODULE,
359         .name           = "nfs4",
360         .mount          = nfs4_referral_mount,
361         .kill_sb        = nfs4_kill_super,
362         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
363 };
364
365 static const struct super_operations nfs4_sops = {
366         .alloc_inode    = nfs_alloc_inode,
367         .destroy_inode  = nfs_destroy_inode,
368         .write_inode    = nfs_write_inode,
369         .put_super      = nfs_put_super,
370         .statfs         = nfs_statfs,
371         .evict_inode    = nfs4_evict_inode,
372         .umount_begin   = nfs_umount_begin,
373         .show_options   = nfs_show_options,
374         .show_devname   = nfs_show_devname,
375         .show_path      = nfs_show_path,
376         .show_stats     = nfs_show_stats,
377         .remount_fs     = nfs_remount,
378 };
379 #endif
380
381 static struct shrinker acl_shrinker = {
382         .shrink         = nfs_access_cache_shrinker,
383         .seeks          = DEFAULT_SEEKS,
384 };
385
386 /*
387  * Register the NFS filesystems
388  */
389 int __init register_nfs_fs(void)
390 {
391         int ret;
392
393         ret = register_filesystem(&nfs_fs_type);
394         if (ret < 0)
395                 goto error_0;
396
397         ret = nfs_register_sysctl();
398         if (ret < 0)
399                 goto error_1;
400 #ifdef CONFIG_NFS_V4
401         ret = register_filesystem(&nfs4_fs_type);
402         if (ret < 0)
403                 goto error_2;
404 #endif
405         register_shrinker(&acl_shrinker);
406         return 0;
407
408 #ifdef CONFIG_NFS_V4
409 error_2:
410         nfs_unregister_sysctl();
411 #endif
412 error_1:
413         unregister_filesystem(&nfs_fs_type);
414 error_0:
415         return ret;
416 }
417
418 /*
419  * Unregister the NFS filesystems
420  */
421 void __exit unregister_nfs_fs(void)
422 {
423         unregister_shrinker(&acl_shrinker);
424 #ifdef CONFIG_NFS_V4
425         unregister_filesystem(&nfs4_fs_type);
426 #endif
427         nfs_unregister_sysctl();
428         unregister_filesystem(&nfs_fs_type);
429 }
430
431 void nfs_sb_active(struct super_block *sb)
432 {
433         struct nfs_server *server = NFS_SB(sb);
434
435         if (atomic_inc_return(&server->active) == 1)
436                 atomic_inc(&sb->s_active);
437 }
438
439 void nfs_sb_deactive(struct super_block *sb)
440 {
441         struct nfs_server *server = NFS_SB(sb);
442
443         if (atomic_dec_and_test(&server->active))
444                 deactivate_super(sb);
445 }
446
447 /*
448  * Deliver file system statistics to userspace
449  */
450 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
451 {
452         struct nfs_server *server = NFS_SB(dentry->d_sb);
453         unsigned char blockbits;
454         unsigned long blockres;
455         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
456         struct nfs_fsstat res;
457         int error = -ENOMEM;
458
459         res.fattr = nfs_alloc_fattr();
460         if (res.fattr == NULL)
461                 goto out_err;
462
463         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
464         if (unlikely(error == -ESTALE)) {
465                 struct dentry *pd_dentry;
466
467                 pd_dentry = dget_parent(dentry);
468                 if (pd_dentry != NULL) {
469                         nfs_zap_caches(pd_dentry->d_inode);
470                         dput(pd_dentry);
471                 }
472         }
473         nfs_free_fattr(res.fattr);
474         if (error < 0)
475                 goto out_err;
476
477         buf->f_type = NFS_SUPER_MAGIC;
478
479         /*
480          * Current versions of glibc do not correctly handle the
481          * case where f_frsize != f_bsize.  Eventually we want to
482          * report the value of wtmult in this field.
483          */
484         buf->f_frsize = dentry->d_sb->s_blocksize;
485
486         /*
487          * On most *nix systems, f_blocks, f_bfree, and f_bavail
488          * are reported in units of f_frsize.  Linux hasn't had
489          * an f_frsize field in its statfs struct until recently,
490          * thus historically Linux's sys_statfs reports these
491          * fields in units of f_bsize.
492          */
493         buf->f_bsize = dentry->d_sb->s_blocksize;
494         blockbits = dentry->d_sb->s_blocksize_bits;
495         blockres = (1 << blockbits) - 1;
496         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
497         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
498         buf->f_bavail = (res.abytes + blockres) >> blockbits;
499
500         buf->f_files = res.tfiles;
501         buf->f_ffree = res.afiles;
502
503         buf->f_namelen = server->namelen;
504
505         return 0;
506
507  out_err:
508         dprintk("%s: statfs error = %d\n", __func__, -error);
509         return error;
510 }
511
512 /*
513  * Map the security flavour number to a name
514  */
515 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
516 {
517         static const struct {
518                 rpc_authflavor_t flavour;
519                 const char *str;
520         } sec_flavours[] = {
521                 { RPC_AUTH_NULL, "null" },
522                 { RPC_AUTH_UNIX, "sys" },
523                 { RPC_AUTH_GSS_KRB5, "krb5" },
524                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
525                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
526                 { RPC_AUTH_GSS_LKEY, "lkey" },
527                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
528                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
529                 { RPC_AUTH_GSS_SPKM, "spkm" },
530                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
531                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
532                 { UINT_MAX, "unknown" }
533         };
534         int i;
535
536         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
537                 if (sec_flavours[i].flavour == flavour)
538                         break;
539         }
540         return sec_flavours[i].str;
541 }
542
543 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
544                                   int showdefaults)
545 {
546         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
547
548         seq_printf(m, ",mountproto=");
549         switch (sap->sa_family) {
550         case AF_INET:
551                 switch (nfss->mountd_protocol) {
552                 case IPPROTO_UDP:
553                         seq_printf(m, RPCBIND_NETID_UDP);
554                         break;
555                 case IPPROTO_TCP:
556                         seq_printf(m, RPCBIND_NETID_TCP);
557                         break;
558                 default:
559                         if (showdefaults)
560                                 seq_printf(m, "auto");
561                 }
562                 break;
563         case AF_INET6:
564                 switch (nfss->mountd_protocol) {
565                 case IPPROTO_UDP:
566                         seq_printf(m, RPCBIND_NETID_UDP6);
567                         break;
568                 case IPPROTO_TCP:
569                         seq_printf(m, RPCBIND_NETID_TCP6);
570                         break;
571                 default:
572                         if (showdefaults)
573                                 seq_printf(m, "auto");
574                 }
575                 break;
576         default:
577                 if (showdefaults)
578                         seq_printf(m, "auto");
579         }
580 }
581
582 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
583                                     int showdefaults)
584 {
585         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
586
587         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
588                 return;
589
590         switch (sap->sa_family) {
591         case AF_INET: {
592                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
593                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
594                 break;
595         }
596         case AF_INET6: {
597                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
598                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
599                 break;
600         }
601         default:
602                 if (showdefaults)
603                         seq_printf(m, ",mountaddr=unspecified");
604         }
605
606         if (nfss->mountd_version || showdefaults)
607                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
608         if ((nfss->mountd_port &&
609                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
610                 showdefaults)
611                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
612
613         nfs_show_mountd_netid(m, nfss, showdefaults);
614 }
615
616 #ifdef CONFIG_NFS_V4
617 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
618                                     int showdefaults)
619 {
620         struct nfs_client *clp = nfss->nfs_client;
621
622         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
623         seq_printf(m, ",minorversion=%u", clp->cl_minorversion);
624 }
625 #else
626 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
627                                     int showdefaults)
628 {
629 }
630 #endif
631
632 /*
633  * Describe the mount options in force on this server representation
634  */
635 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
636                                    int showdefaults)
637 {
638         static const struct proc_nfs_info {
639                 int flag;
640                 const char *str;
641                 const char *nostr;
642         } nfs_info[] = {
643                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
644                 { NFS_MOUNT_POSIX, ",posix", "" },
645                 { NFS_MOUNT_NOCTO, ",nocto", "" },
646                 { NFS_MOUNT_NOAC, ",noac", "" },
647                 { NFS_MOUNT_NONLM, ",nolock", "" },
648                 { NFS_MOUNT_NOACL, ",noacl", "" },
649                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
650                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
651                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
652                 { 0, NULL, NULL }
653         };
654         const struct proc_nfs_info *nfs_infop;
655         struct nfs_client *clp = nfss->nfs_client;
656         u32 version = clp->rpc_ops->version;
657         int local_flock, local_fcntl;
658
659         seq_printf(m, ",vers=%u", version);
660         seq_printf(m, ",rsize=%u", nfss->rsize);
661         seq_printf(m, ",wsize=%u", nfss->wsize);
662         if (nfss->bsize != 0)
663                 seq_printf(m, ",bsize=%u", nfss->bsize);
664         seq_printf(m, ",namlen=%u", nfss->namelen);
665         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
666                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
667         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
668                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
669         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
670                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
671         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
672                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
673         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
674                 if (nfss->flags & nfs_infop->flag)
675                         seq_puts(m, nfs_infop->str);
676                 else
677                         seq_puts(m, nfs_infop->nostr);
678         }
679         seq_printf(m, ",proto=%s",
680                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
681         if (version == 4) {
682                 if (nfss->port != NFS_PORT)
683                         seq_printf(m, ",port=%u", nfss->port);
684         } else
685                 if (nfss->port)
686                         seq_printf(m, ",port=%u", nfss->port);
687
688         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
689         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
690         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
691
692         if (version != 4)
693                 nfs_show_mountd_options(m, nfss, showdefaults);
694         else
695                 nfs_show_nfsv4_options(m, nfss, showdefaults);
696
697         if (nfss->options & NFS_OPTION_FSCACHE)
698                 seq_printf(m, ",fsc");
699
700         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
701                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
702                         seq_printf(m, ",lookupcache=none");
703                 else
704                         seq_printf(m, ",lookupcache=pos");
705         }
706
707         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
708         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
709
710         if (!local_flock && !local_fcntl)
711                 seq_printf(m, ",local_lock=none");
712         else if (local_flock && local_fcntl)
713                 seq_printf(m, ",local_lock=all");
714         else if (local_flock)
715                 seq_printf(m, ",local_lock=flock");
716         else
717                 seq_printf(m, ",local_lock=posix");
718 }
719
720 /*
721  * Describe the mount options on this VFS mountpoint
722  */
723 static int nfs_show_options(struct seq_file *m, struct dentry *root)
724 {
725         struct nfs_server *nfss = NFS_SB(root->d_sb);
726
727         nfs_show_mount_options(m, nfss, 0);
728
729         seq_printf(m, ",addr=%s",
730                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
731                                                         RPC_DISPLAY_ADDR));
732
733         return 0;
734 }
735
736 #ifdef CONFIG_NFS_V4
737 #ifdef CONFIG_NFS_V4_1
738 static void show_sessions(struct seq_file *m, struct nfs_server *server)
739 {
740         if (nfs4_has_session(server->nfs_client))
741                 seq_printf(m, ",sessions");
742 }
743 #else
744 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
745 #endif
746 #endif
747
748 #ifdef CONFIG_NFS_V4
749 #ifdef CONFIG_NFS_V4_1
750 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
751 {
752         seq_printf(m, ",pnfs=");
753         if (server->pnfs_curr_ld)
754                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
755         else
756                 seq_printf(m, "not configured");
757 }
758 #else
759 static void show_pnfs(struct seq_file *m, struct nfs_server *server) {}
760 #endif
761 #endif
762
763 static int nfs_show_devname(struct seq_file *m, struct dentry *root)
764 {
765         char *page = (char *) __get_free_page(GFP_KERNEL);
766         char *devname, *dummy;
767         int err = 0;
768         if (!page)
769                 return -ENOMEM;
770         devname = nfs_path(&dummy, root, page, PAGE_SIZE);
771         if (IS_ERR(devname))
772                 err = PTR_ERR(devname);
773         else
774                 seq_escape(m, devname, " \t\n\\");
775         free_page((unsigned long)page);
776         return err;
777 }
778
779 static int nfs_show_path(struct seq_file *m, struct dentry *dentry)
780 {
781         seq_puts(m, "/");
782         return 0;
783 }
784
785 /*
786  * Present statistical information for this VFS mountpoint
787  */
788 static int nfs_show_stats(struct seq_file *m, struct dentry *root)
789 {
790         int i, cpu;
791         struct nfs_server *nfss = NFS_SB(root->d_sb);
792         struct rpc_auth *auth = nfss->client->cl_auth;
793         struct nfs_iostats totals = { };
794
795         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
796
797         /*
798          * Display all mount option settings
799          */
800         seq_printf(m, "\n\topts:\t");
801         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
802         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
803         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
804         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
805         nfs_show_mount_options(m, nfss, 1);
806
807         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
808
809         seq_printf(m, "\n\tcaps:\t");
810         seq_printf(m, "caps=0x%x", nfss->caps);
811         seq_printf(m, ",wtmult=%u", nfss->wtmult);
812         seq_printf(m, ",dtsize=%u", nfss->dtsize);
813         seq_printf(m, ",bsize=%u", nfss->bsize);
814         seq_printf(m, ",namlen=%u", nfss->namelen);
815
816 #ifdef CONFIG_NFS_V4
817         if (nfss->nfs_client->rpc_ops->version == 4) {
818                 seq_printf(m, "\n\tnfsv4:\t");
819                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
820                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
821                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
822                 show_sessions(m, nfss);
823                 show_pnfs(m, nfss);
824         }
825 #endif
826
827         /*
828          * Display security flavor in effect for this mount
829          */
830         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
831         if (auth->au_flavor)
832                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
833
834         /*
835          * Display superblock I/O counters
836          */
837         for_each_possible_cpu(cpu) {
838                 struct nfs_iostats *stats;
839
840                 preempt_disable();
841                 stats = per_cpu_ptr(nfss->io_stats, cpu);
842
843                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
844                         totals.events[i] += stats->events[i];
845                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
846                         totals.bytes[i] += stats->bytes[i];
847 #ifdef CONFIG_NFS_FSCACHE
848                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
849                         totals.fscache[i] += stats->fscache[i];
850 #endif
851
852                 preempt_enable();
853         }
854
855         seq_printf(m, "\n\tevents:\t");
856         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
857                 seq_printf(m, "%lu ", totals.events[i]);
858         seq_printf(m, "\n\tbytes:\t");
859         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
860                 seq_printf(m, "%Lu ", totals.bytes[i]);
861 #ifdef CONFIG_NFS_FSCACHE
862         if (nfss->options & NFS_OPTION_FSCACHE) {
863                 seq_printf(m, "\n\tfsc:\t");
864                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
865                         seq_printf(m, "%Lu ", totals.bytes[i]);
866         }
867 #endif
868         seq_printf(m, "\n");
869
870         rpc_print_iostats(m, nfss->client);
871
872         return 0;
873 }
874
875 /*
876  * Begin unmount by attempting to remove all automounted mountpoints we added
877  * in response to xdev traversals and referrals
878  */
879 static void nfs_umount_begin(struct super_block *sb)
880 {
881         struct nfs_server *server;
882         struct rpc_clnt *rpc;
883
884         server = NFS_SB(sb);
885         /* -EIO all pending I/O */
886         rpc = server->client_acl;
887         if (!IS_ERR(rpc))
888                 rpc_killall_tasks(rpc);
889         rpc = server->client;
890         if (!IS_ERR(rpc))
891                 rpc_killall_tasks(rpc);
892 }
893
894 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
895 {
896         struct nfs_parsed_mount_data *data;
897
898         data = kzalloc(sizeof(*data), GFP_KERNEL);
899         if (data) {
900                 data->acregmin          = NFS_DEF_ACREGMIN;
901                 data->acregmax          = NFS_DEF_ACREGMAX;
902                 data->acdirmin          = NFS_DEF_ACDIRMIN;
903                 data->acdirmax          = NFS_DEF_ACDIRMAX;
904                 data->mount_server.port = NFS_UNSPEC_PORT;
905                 data->nfs_server.port   = NFS_UNSPEC_PORT;
906                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
907                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
908                 data->auth_flavor_len   = 1;
909                 data->version           = version;
910                 data->minorversion      = 0;
911                 security_init_mnt_opts(&data->lsm_opts);
912         }
913         return data;
914 }
915
916 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
917 {
918         if (data) {
919                 kfree(data->client_address);
920                 kfree(data->mount_server.hostname);
921                 kfree(data->nfs_server.export_path);
922                 kfree(data->nfs_server.hostname);
923                 kfree(data->fscache_uniq);
924                 security_free_mnt_opts(&data->lsm_opts);
925                 kfree(data);
926         }
927 }
928
929 /*
930  * Sanity-check a server address provided by the mount command.
931  *
932  * Address family must be initialized, and address must not be
933  * the ANY address for that family.
934  */
935 static int nfs_verify_server_address(struct sockaddr *addr)
936 {
937         switch (addr->sa_family) {
938         case AF_INET: {
939                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
940                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
941         }
942         case AF_INET6: {
943                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
944                 return !ipv6_addr_any(sa);
945         }
946         }
947
948         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
949         return 0;
950 }
951
952 /*
953  * Select between a default port value and a user-specified port value.
954  * If a zero value is set, then autobind will be used.
955  */
956 static void nfs_set_port(struct sockaddr *sap, int *port,
957                                  const unsigned short default_port)
958 {
959         if (*port == NFS_UNSPEC_PORT)
960                 *port = default_port;
961
962         rpc_set_port(sap, *port);
963 }
964
965 /*
966  * Sanity check the NFS transport protocol.
967  *
968  */
969 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
970 {
971         switch (mnt->nfs_server.protocol) {
972         case XPRT_TRANSPORT_UDP:
973         case XPRT_TRANSPORT_TCP:
974         case XPRT_TRANSPORT_RDMA:
975                 break;
976         default:
977                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
978         }
979 }
980
981 /*
982  * For text based NFSv2/v3 mounts, the mount protocol transport default
983  * settings should depend upon the specified NFS transport.
984  */
985 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
986 {
987         nfs_validate_transport_protocol(mnt);
988
989         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
990             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
991                         return;
992         switch (mnt->nfs_server.protocol) {
993         case XPRT_TRANSPORT_UDP:
994                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
995                 break;
996         case XPRT_TRANSPORT_TCP:
997         case XPRT_TRANSPORT_RDMA:
998                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
999         }
1000 }
1001
1002 /*
1003  * Parse the value of the 'sec=' option.
1004  */
1005 static int nfs_parse_security_flavors(char *value,
1006                                       struct nfs_parsed_mount_data *mnt)
1007 {
1008         substring_t args[MAX_OPT_ARGS];
1009
1010         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1011
1012         switch (match_token(value, nfs_secflavor_tokens, args)) {
1013         case Opt_sec_none:
1014                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1015                 break;
1016         case Opt_sec_sys:
1017                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1018                 break;
1019         case Opt_sec_krb5:
1020                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1021                 break;
1022         case Opt_sec_krb5i:
1023                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1024                 break;
1025         case Opt_sec_krb5p:
1026                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1027                 break;
1028         case Opt_sec_lkey:
1029                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1030                 break;
1031         case Opt_sec_lkeyi:
1032                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1033                 break;
1034         case Opt_sec_lkeyp:
1035                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1036                 break;
1037         case Opt_sec_spkm:
1038                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1039                 break;
1040         case Opt_sec_spkmi:
1041                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1042                 break;
1043         case Opt_sec_spkmp:
1044                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1045                 break;
1046         default:
1047                 return 0;
1048         }
1049
1050         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1051         mnt->auth_flavor_len = 1;
1052         return 1;
1053 }
1054
1055 static int nfs_get_option_str(substring_t args[], char **option)
1056 {
1057         kfree(*option);
1058         *option = match_strdup(args);
1059         return !option;
1060 }
1061
1062 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1063 {
1064         int rc;
1065         char *string;
1066
1067         string = match_strdup(args);
1068         if (string == NULL)
1069                 return -ENOMEM;
1070         rc = strict_strtoul(string, 10, option);
1071         kfree(string);
1072
1073         return rc;
1074 }
1075
1076 /*
1077  * Error-check and convert a string of mount options from user space into
1078  * a data structure.  The whole mount string is processed; bad options are
1079  * skipped as they are encountered.  If there were no errors, return 1;
1080  * otherwise return 0 (zero).
1081  */
1082 static int nfs_parse_mount_options(char *raw,
1083                                    struct nfs_parsed_mount_data *mnt)
1084 {
1085         char *p, *string, *secdata;
1086         int rc, sloppy = 0, invalid_option = 0;
1087         unsigned short protofamily = AF_UNSPEC;
1088         unsigned short mountfamily = AF_UNSPEC;
1089
1090         if (!raw) {
1091                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1092                 return 1;
1093         }
1094         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1095
1096         secdata = alloc_secdata();
1097         if (!secdata)
1098                 goto out_nomem;
1099
1100         rc = security_sb_copy_data(raw, secdata);
1101         if (rc)
1102                 goto out_security_failure;
1103
1104         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1105         if (rc)
1106                 goto out_security_failure;
1107
1108         free_secdata(secdata);
1109
1110         while ((p = strsep(&raw, ",")) != NULL) {
1111                 substring_t args[MAX_OPT_ARGS];
1112                 unsigned long option;
1113                 int token;
1114
1115                 if (!*p)
1116                         continue;
1117
1118                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1119
1120                 token = match_token(p, nfs_mount_option_tokens, args);
1121                 switch (token) {
1122
1123                 /*
1124                  * boolean options:  foo/nofoo
1125                  */
1126                 case Opt_soft:
1127                         mnt->flags |= NFS_MOUNT_SOFT;
1128                         break;
1129                 case Opt_hard:
1130                         mnt->flags &= ~NFS_MOUNT_SOFT;
1131                         break;
1132                 case Opt_posix:
1133                         mnt->flags |= NFS_MOUNT_POSIX;
1134                         break;
1135                 case Opt_noposix:
1136                         mnt->flags &= ~NFS_MOUNT_POSIX;
1137                         break;
1138                 case Opt_cto:
1139                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1140                         break;
1141                 case Opt_nocto:
1142                         mnt->flags |= NFS_MOUNT_NOCTO;
1143                         break;
1144                 case Opt_ac:
1145                         mnt->flags &= ~NFS_MOUNT_NOAC;
1146                         break;
1147                 case Opt_noac:
1148                         mnt->flags |= NFS_MOUNT_NOAC;
1149                         break;
1150                 case Opt_lock:
1151                         mnt->flags &= ~NFS_MOUNT_NONLM;
1152                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1153                                         NFS_MOUNT_LOCAL_FCNTL);
1154                         break;
1155                 case Opt_nolock:
1156                         mnt->flags |= NFS_MOUNT_NONLM;
1157                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1158                                        NFS_MOUNT_LOCAL_FCNTL);
1159                         break;
1160                 case Opt_v2:
1161                         mnt->flags &= ~NFS_MOUNT_VER3;
1162                         mnt->version = 2;
1163                         break;
1164                 case Opt_v3:
1165                         mnt->flags |= NFS_MOUNT_VER3;
1166                         mnt->version = 3;
1167                         break;
1168                 case Opt_v4:
1169                         mnt->flags &= ~NFS_MOUNT_VER3;
1170                         mnt->version = 4;
1171                         break;
1172                 case Opt_udp:
1173                         mnt->flags &= ~NFS_MOUNT_TCP;
1174                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1175                         break;
1176                 case Opt_tcp:
1177                         mnt->flags |= NFS_MOUNT_TCP;
1178                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1179                         break;
1180                 case Opt_rdma:
1181                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1182                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1183                         xprt_load_transport(p);
1184                         break;
1185                 case Opt_acl:
1186                         mnt->flags &= ~NFS_MOUNT_NOACL;
1187                         break;
1188                 case Opt_noacl:
1189                         mnt->flags |= NFS_MOUNT_NOACL;
1190                         break;
1191                 case Opt_rdirplus:
1192                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1193                         break;
1194                 case Opt_nordirplus:
1195                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1196                         break;
1197                 case Opt_sharecache:
1198                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1199                         break;
1200                 case Opt_nosharecache:
1201                         mnt->flags |= NFS_MOUNT_UNSHARED;
1202                         break;
1203                 case Opt_resvport:
1204                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1205                         break;
1206                 case Opt_noresvport:
1207                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1208                         break;
1209                 case Opt_fscache:
1210                         mnt->options |= NFS_OPTION_FSCACHE;
1211                         kfree(mnt->fscache_uniq);
1212                         mnt->fscache_uniq = NULL;
1213                         break;
1214                 case Opt_nofscache:
1215                         mnt->options &= ~NFS_OPTION_FSCACHE;
1216                         kfree(mnt->fscache_uniq);
1217                         mnt->fscache_uniq = NULL;
1218                         break;
1219
1220                 /*
1221                  * options that take numeric values
1222                  */
1223                 case Opt_port:
1224                         if (nfs_get_option_ul(args, &option) ||
1225                             option > USHRT_MAX)
1226                                 goto out_invalid_value;
1227                         mnt->nfs_server.port = option;
1228                         break;
1229                 case Opt_rsize:
1230                         if (nfs_get_option_ul(args, &option))
1231                                 goto out_invalid_value;
1232                         mnt->rsize = option;
1233                         break;
1234                 case Opt_wsize:
1235                         if (nfs_get_option_ul(args, &option))
1236                                 goto out_invalid_value;
1237                         mnt->wsize = option;
1238                         break;
1239                 case Opt_bsize:
1240                         if (nfs_get_option_ul(args, &option))
1241                                 goto out_invalid_value;
1242                         mnt->bsize = option;
1243                         break;
1244                 case Opt_timeo:
1245                         if (nfs_get_option_ul(args, &option) || option == 0)
1246                                 goto out_invalid_value;
1247                         mnt->timeo = option;
1248                         break;
1249                 case Opt_retrans:
1250                         if (nfs_get_option_ul(args, &option) || option == 0)
1251                                 goto out_invalid_value;
1252                         mnt->retrans = option;
1253                         break;
1254                 case Opt_acregmin:
1255                         if (nfs_get_option_ul(args, &option))
1256                                 goto out_invalid_value;
1257                         mnt->acregmin = option;
1258                         break;
1259                 case Opt_acregmax:
1260                         if (nfs_get_option_ul(args, &option))
1261                                 goto out_invalid_value;
1262                         mnt->acregmax = option;
1263                         break;
1264                 case Opt_acdirmin:
1265                         if (nfs_get_option_ul(args, &option))
1266                                 goto out_invalid_value;
1267                         mnt->acdirmin = option;
1268                         break;
1269                 case Opt_acdirmax:
1270                         if (nfs_get_option_ul(args, &option))
1271                                 goto out_invalid_value;
1272                         mnt->acdirmax = option;
1273                         break;
1274                 case Opt_actimeo:
1275                         if (nfs_get_option_ul(args, &option))
1276                                 goto out_invalid_value;
1277                         mnt->acregmin = mnt->acregmax =
1278                         mnt->acdirmin = mnt->acdirmax = option;
1279                         break;
1280                 case Opt_namelen:
1281                         if (nfs_get_option_ul(args, &option))
1282                                 goto out_invalid_value;
1283                         mnt->namlen = option;
1284                         break;
1285                 case Opt_mountport:
1286                         if (nfs_get_option_ul(args, &option) ||
1287                             option > USHRT_MAX)
1288                                 goto out_invalid_value;
1289                         mnt->mount_server.port = option;
1290                         break;
1291                 case Opt_mountvers:
1292                         if (nfs_get_option_ul(args, &option) ||
1293                             option < NFS_MNT_VERSION ||
1294                             option > NFS_MNT3_VERSION)
1295                                 goto out_invalid_value;
1296                         mnt->mount_server.version = option;
1297                         break;
1298                 case Opt_nfsvers:
1299                         if (nfs_get_option_ul(args, &option))
1300                                 goto out_invalid_value;
1301                         switch (option) {
1302                         case NFS2_VERSION:
1303                                 mnt->flags &= ~NFS_MOUNT_VER3;
1304                                 mnt->version = 2;
1305                                 break;
1306                         case NFS3_VERSION:
1307                                 mnt->flags |= NFS_MOUNT_VER3;
1308                                 mnt->version = 3;
1309                                 break;
1310                         case NFS4_VERSION:
1311                                 mnt->flags &= ~NFS_MOUNT_VER3;
1312                                 mnt->version = 4;
1313                                 break;
1314                         default:
1315                                 goto out_invalid_value;
1316                         }
1317                         break;
1318                 case Opt_minorversion:
1319                         if (nfs_get_option_ul(args, &option))
1320                                 goto out_invalid_value;
1321                         if (option > NFS4_MAX_MINOR_VERSION)
1322                                 goto out_invalid_value;
1323                         mnt->minorversion = option;
1324                         break;
1325
1326                 /*
1327                  * options that take text values
1328                  */
1329                 case Opt_sec:
1330                         string = match_strdup(args);
1331                         if (string == NULL)
1332                                 goto out_nomem;
1333                         rc = nfs_parse_security_flavors(string, mnt);
1334                         kfree(string);
1335                         if (!rc) {
1336                                 dfprintk(MOUNT, "NFS:   unrecognized "
1337                                                 "security flavor\n");
1338                                 return 0;
1339                         }
1340                         break;
1341                 case Opt_proto:
1342                         string = match_strdup(args);
1343                         if (string == NULL)
1344                                 goto out_nomem;
1345                         token = match_token(string,
1346                                             nfs_xprt_protocol_tokens, args);
1347
1348                         protofamily = AF_INET;
1349                         switch (token) {
1350                         case Opt_xprt_udp6:
1351                                 protofamily = AF_INET6;
1352                         case Opt_xprt_udp:
1353                                 mnt->flags &= ~NFS_MOUNT_TCP;
1354                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1355                                 break;
1356                         case Opt_xprt_tcp6:
1357                                 protofamily = AF_INET6;
1358                         case Opt_xprt_tcp:
1359                                 mnt->flags |= NFS_MOUNT_TCP;
1360                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1361                                 break;
1362                         case Opt_xprt_rdma:
1363                                 /* vector side protocols to TCP */
1364                                 mnt->flags |= NFS_MOUNT_TCP;
1365                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1366                                 xprt_load_transport(string);
1367                                 break;
1368                         default:
1369                                 dfprintk(MOUNT, "NFS:   unrecognized "
1370                                                 "transport protocol\n");
1371                                 kfree(string);
1372                                 return 0;
1373                         }
1374                         kfree(string);
1375                         break;
1376                 case Opt_mountproto:
1377                         string = match_strdup(args);
1378                         if (string == NULL)
1379                                 goto out_nomem;
1380                         token = match_token(string,
1381                                             nfs_xprt_protocol_tokens, args);
1382                         kfree(string);
1383
1384                         mountfamily = AF_INET;
1385                         switch (token) {
1386                         case Opt_xprt_udp6:
1387                                 mountfamily = AF_INET6;
1388                         case Opt_xprt_udp:
1389                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1390                                 break;
1391                         case Opt_xprt_tcp6:
1392                                 mountfamily = AF_INET6;
1393                         case Opt_xprt_tcp:
1394                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1395                                 break;
1396                         case Opt_xprt_rdma: /* not used for side protocols */
1397                         default:
1398                                 dfprintk(MOUNT, "NFS:   unrecognized "
1399                                                 "transport protocol\n");
1400                                 return 0;
1401                         }
1402                         break;
1403                 case Opt_addr:
1404                         string = match_strdup(args);
1405                         if (string == NULL)
1406                                 goto out_nomem;
1407                         mnt->nfs_server.addrlen =
1408                                 rpc_pton(string, strlen(string),
1409                                         (struct sockaddr *)
1410                                         &mnt->nfs_server.address,
1411                                         sizeof(mnt->nfs_server.address));
1412                         kfree(string);
1413                         if (mnt->nfs_server.addrlen == 0)
1414                                 goto out_invalid_address;
1415                         break;
1416                 case Opt_clientaddr:
1417                         if (nfs_get_option_str(args, &mnt->client_address))
1418                                 goto out_nomem;
1419                         break;
1420                 case Opt_mounthost:
1421                         if (nfs_get_option_str(args,
1422                                                &mnt->mount_server.hostname))
1423                                 goto out_nomem;
1424                         break;
1425                 case Opt_mountaddr:
1426                         string = match_strdup(args);
1427                         if (string == NULL)
1428                                 goto out_nomem;
1429                         mnt->mount_server.addrlen =
1430                                 rpc_pton(string, strlen(string),
1431                                         (struct sockaddr *)
1432                                         &mnt->mount_server.address,
1433                                         sizeof(mnt->mount_server.address));
1434                         kfree(string);
1435                         if (mnt->mount_server.addrlen == 0)
1436                                 goto out_invalid_address;
1437                         break;
1438                 case Opt_lookupcache:
1439                         string = match_strdup(args);
1440                         if (string == NULL)
1441                                 goto out_nomem;
1442                         token = match_token(string,
1443                                         nfs_lookupcache_tokens, args);
1444                         kfree(string);
1445                         switch (token) {
1446                                 case Opt_lookupcache_all:
1447                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1448                                         break;
1449                                 case Opt_lookupcache_positive:
1450                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1451                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1452                                         break;
1453                                 case Opt_lookupcache_none:
1454                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1455                                         break;
1456                                 default:
1457                                         dfprintk(MOUNT, "NFS:   invalid "
1458                                                         "lookupcache argument\n");
1459                                         return 0;
1460                         };
1461                         break;
1462                 case Opt_fscache_uniq:
1463                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1464                                 goto out_nomem;
1465                         mnt->options |= NFS_OPTION_FSCACHE;
1466                         break;
1467                 case Opt_local_lock:
1468                         string = match_strdup(args);
1469                         if (string == NULL)
1470                                 goto out_nomem;
1471                         token = match_token(string, nfs_local_lock_tokens,
1472                                         args);
1473                         kfree(string);
1474                         switch (token) {
1475                         case Opt_local_lock_all:
1476                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1477                                                NFS_MOUNT_LOCAL_FCNTL);
1478                                 break;
1479                         case Opt_local_lock_flock:
1480                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1481                                 break;
1482                         case Opt_local_lock_posix:
1483                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1484                                 break;
1485                         case Opt_local_lock_none:
1486                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1487                                                 NFS_MOUNT_LOCAL_FCNTL);
1488                                 break;
1489                         default:
1490                                 dfprintk(MOUNT, "NFS:   invalid "
1491                                                 "local_lock argument\n");
1492                                 return 0;
1493                         };
1494                         break;
1495
1496                 /*
1497                  * Special options
1498                  */
1499                 case Opt_sloppy:
1500                         sloppy = 1;
1501                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1502                         break;
1503                 case Opt_userspace:
1504                 case Opt_deprecated:
1505                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1506                                         "'%s'\n", p);
1507                         break;
1508
1509                 default:
1510                         invalid_option = 1;
1511                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1512                                         "'%s'\n", p);
1513                 }
1514         }
1515
1516         if (!sloppy && invalid_option)
1517                 return 0;
1518
1519         /*
1520          * verify that any proto=/mountproto= options match the address
1521          * familiies in the addr=/mountaddr= options.
1522          */
1523         if (protofamily != AF_UNSPEC &&
1524             protofamily != mnt->nfs_server.address.ss_family)
1525                 goto out_proto_mismatch;
1526
1527         if (mountfamily != AF_UNSPEC) {
1528                 if (mnt->mount_server.addrlen) {
1529                         if (mountfamily != mnt->mount_server.address.ss_family)
1530                                 goto out_mountproto_mismatch;
1531                 } else {
1532                         if (mountfamily != mnt->nfs_server.address.ss_family)
1533                                 goto out_mountproto_mismatch;
1534                 }
1535         }
1536
1537         return 1;
1538
1539 out_mountproto_mismatch:
1540         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1541                          "option\n");
1542         return 0;
1543 out_proto_mismatch:
1544         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1545         return 0;
1546 out_invalid_address:
1547         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1548         return 0;
1549 out_invalid_value:
1550         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1551         return 0;
1552 out_nomem:
1553         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1554         return 0;
1555 out_security_failure:
1556         free_secdata(secdata);
1557         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1558         return 0;
1559 }
1560
1561 /*
1562  * Match the requested auth flavors with the list returned by
1563  * the server.  Returns zero and sets the mount's authentication
1564  * flavor on success; returns -EACCES if server does not support
1565  * the requested flavor.
1566  */
1567 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1568                              struct nfs_mount_request *request)
1569 {
1570         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1571
1572         /*
1573          * Certain releases of Linux's mountd return an empty
1574          * flavor list.  To prevent behavioral regression with
1575          * these servers (ie. rejecting mounts that used to
1576          * succeed), revert to pre-2.6.32 behavior (no checking)
1577          * if the returned flavor list is empty.
1578          */
1579         if (server_authlist_len == 0)
1580                 return 0;
1581
1582         /*
1583          * We avoid sophisticated negotiating here, as there are
1584          * plenty of cases where we can get it wrong, providing
1585          * either too little or too much security.
1586          *
1587          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1588          * flavor listed first.  However, some servers list
1589          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1590          * preferred default, in args->auth_flavors[0] if user
1591          * didn't specify sec= mount option.
1592          */
1593         for (i = 0; i < args->auth_flavor_len; i++)
1594                 for (j = 0; j < server_authlist_len; j++)
1595                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1596                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1597                                         request->auth_flavs[j]);
1598                                 args->auth_flavors[0] = request->auth_flavs[j];
1599                                 return 0;
1600                         }
1601
1602         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1603         nfs_umount(request);
1604         return -EACCES;
1605 }
1606
1607 /*
1608  * Use the remote server's MOUNT service to request the NFS file handle
1609  * corresponding to the provided path.
1610  */
1611 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1612                          struct nfs_fh *root_fh)
1613 {
1614         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1615         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1616         struct nfs_mount_request request = {
1617                 .sap            = (struct sockaddr *)
1618                                                 &args->mount_server.address,
1619                 .dirpath        = args->nfs_server.export_path,
1620                 .protocol       = args->mount_server.protocol,
1621                 .fh             = root_fh,
1622                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1623                 .auth_flav_len  = &server_authlist_len,
1624                 .auth_flavs     = server_authlist,
1625         };
1626         int status;
1627
1628         if (args->mount_server.version == 0) {
1629                 switch (args->version) {
1630                         default:
1631                                 args->mount_server.version = NFS_MNT3_VERSION;
1632                                 break;
1633                         case 2:
1634                                 args->mount_server.version = NFS_MNT_VERSION;
1635                 }
1636         }
1637         request.version = args->mount_server.version;
1638
1639         if (args->mount_server.hostname)
1640                 request.hostname = args->mount_server.hostname;
1641         else
1642                 request.hostname = args->nfs_server.hostname;
1643
1644         /*
1645          * Construct the mount server's address.
1646          */
1647         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1648                 memcpy(request.sap, &args->nfs_server.address,
1649                        args->nfs_server.addrlen);
1650                 args->mount_server.addrlen = args->nfs_server.addrlen;
1651         }
1652         request.salen = args->mount_server.addrlen;
1653         nfs_set_port(request.sap, &args->mount_server.port, 0);
1654
1655         /*
1656          * Now ask the mount server to map our export path
1657          * to a file handle.
1658          */
1659         status = nfs_mount(&request);
1660         if (status != 0) {
1661                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1662                                 request.hostname, status);
1663                 return status;
1664         }
1665
1666         /*
1667          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1668          */
1669         if (args->mount_server.version != NFS_MNT3_VERSION)
1670                 return 0;
1671         return nfs_walk_authlist(args, &request);
1672 }
1673
1674 /*
1675  * Split "dev_name" into "hostname:export_path".
1676  *
1677  * The leftmost colon demarks the split between the server's hostname
1678  * and the export path.  If the hostname starts with a left square
1679  * bracket, then it may contain colons.
1680  *
1681  * Note: caller frees hostname and export path, even on error.
1682  */
1683 static int nfs_parse_devname(const char *dev_name,
1684                              char **hostname, size_t maxnamlen,
1685                              char **export_path, size_t maxpathlen)
1686 {
1687         size_t len;
1688         char *end;
1689
1690         /* Is the host name protected with square brakcets? */
1691         if (*dev_name == '[') {
1692                 end = strchr(++dev_name, ']');
1693                 if (end == NULL || end[1] != ':')
1694                         goto out_bad_devname;
1695
1696                 len = end - dev_name;
1697                 end++;
1698         } else {
1699                 char *comma;
1700
1701                 end = strchr(dev_name, ':');
1702                 if (end == NULL)
1703                         goto out_bad_devname;
1704                 len = end - dev_name;
1705
1706                 /* kill possible hostname list: not supported */
1707                 comma = strchr(dev_name, ',');
1708                 if (comma != NULL && comma < end)
1709                         *comma = 0;
1710         }
1711
1712         if (len > maxnamlen)
1713                 goto out_hostname;
1714
1715         /* N.B. caller will free nfs_server.hostname in all cases */
1716         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1717         if (*hostname == NULL)
1718                 goto out_nomem;
1719         len = strlen(++end);
1720         if (len > maxpathlen)
1721                 goto out_path;
1722         *export_path = kstrndup(end, len, GFP_KERNEL);
1723         if (!*export_path)
1724                 goto out_nomem;
1725
1726         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1727         return 0;
1728
1729 out_bad_devname:
1730         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1731         return -EINVAL;
1732
1733 out_nomem:
1734         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1735         return -ENOMEM;
1736
1737 out_hostname:
1738         dfprintk(MOUNT, "NFS: server hostname too long\n");
1739         return -ENAMETOOLONG;
1740
1741 out_path:
1742         dfprintk(MOUNT, "NFS: export pathname too long\n");
1743         return -ENAMETOOLONG;
1744 }
1745
1746 /*
1747  * Validate the NFS2/NFS3 mount data
1748  * - fills in the mount root filehandle
1749  *
1750  * For option strings, user space handles the following behaviors:
1751  *
1752  * + DNS: mapping server host name to IP address ("addr=" option)
1753  *
1754  * + failure mode: how to behave if a mount request can't be handled
1755  *   immediately ("fg/bg" option)
1756  *
1757  * + retry: how often to retry a mount request ("retry=" option)
1758  *
1759  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1760  *   mountproto=tcp after mountproto=udp, and so on
1761  */
1762 static int nfs_validate_mount_data(void *options,
1763                                    struct nfs_parsed_mount_data *args,
1764                                    struct nfs_fh *mntfh,
1765                                    const char *dev_name)
1766 {
1767         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1768         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1769
1770         if (data == NULL)
1771                 goto out_no_data;
1772
1773         switch (data->version) {
1774         case 1:
1775                 data->namlen = 0;
1776         case 2:
1777                 data->bsize = 0;
1778         case 3:
1779                 if (data->flags & NFS_MOUNT_VER3)
1780                         goto out_no_v3;
1781                 data->root.size = NFS2_FHSIZE;
1782                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1783         case 4:
1784                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1785                         goto out_no_sec;
1786         case 5:
1787                 memset(data->context, 0, sizeof(data->context));
1788         case 6:
1789                 if (data->flags & NFS_MOUNT_VER3) {
1790                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1791                                 goto out_invalid_fh;
1792                         mntfh->size = data->root.size;
1793                         args->version = 3;
1794                 } else {
1795                         mntfh->size = NFS2_FHSIZE;
1796                         args->version = 2;
1797                 }
1798
1799
1800                 memcpy(mntfh->data, data->root.data, mntfh->size);
1801                 if (mntfh->size < sizeof(mntfh->data))
1802                         memset(mntfh->data + mntfh->size, 0,
1803                                sizeof(mntfh->data) - mntfh->size);
1804
1805                 /*
1806                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1807                  * can deal with.
1808                  */
1809                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1810                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1811                 args->rsize             = data->rsize;
1812                 args->wsize             = data->wsize;
1813                 args->timeo             = data->timeo;
1814                 args->retrans           = data->retrans;
1815                 args->acregmin          = data->acregmin;
1816                 args->acregmax          = data->acregmax;
1817                 args->acdirmin          = data->acdirmin;
1818                 args->acdirmax          = data->acdirmax;
1819
1820                 memcpy(sap, &data->addr, sizeof(data->addr));
1821                 args->nfs_server.addrlen = sizeof(data->addr);
1822                 if (!nfs_verify_server_address(sap))
1823                         goto out_no_address;
1824
1825                 if (!(data->flags & NFS_MOUNT_TCP))
1826                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1827                 /* N.B. caller will free nfs_server.hostname in all cases */
1828                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1829                 args->namlen            = data->namlen;
1830                 args->bsize             = data->bsize;
1831
1832                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1833                         args->auth_flavors[0] = data->pseudoflavor;
1834                 if (!args->nfs_server.hostname)
1835                         goto out_nomem;
1836
1837                 if (!(data->flags & NFS_MOUNT_NONLM))
1838                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1839                                          NFS_MOUNT_LOCAL_FCNTL);
1840                 else
1841                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1842                                         NFS_MOUNT_LOCAL_FCNTL);
1843                 /*
1844                  * The legacy version 6 binary mount data from userspace has a
1845                  * field used only to transport selinux information into the
1846                  * the kernel.  To continue to support that functionality we
1847                  * have a touch of selinux knowledge here in the NFS code. The
1848                  * userspace code converted context=blah to just blah so we are
1849                  * converting back to the full string selinux understands.
1850                  */
1851                 if (data->context[0]){
1852 #ifdef CONFIG_SECURITY_SELINUX
1853                         int rc;
1854                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1855                         if (!opts_str)
1856                                 return -ENOMEM;
1857                         strcpy(opts_str, "context=");
1858                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1859                         strcat(opts_str, &data->context[0]);
1860                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1861                         kfree(opts_str);
1862                         if (rc)
1863                                 return rc;
1864 #else
1865                         return -EINVAL;
1866 #endif
1867                 }
1868
1869                 break;
1870         default: {
1871                 int status;
1872
1873                 if (nfs_parse_mount_options((char *)options, args) == 0)
1874                         return -EINVAL;
1875
1876                 if (!nfs_verify_server_address(sap))
1877                         goto out_no_address;
1878
1879                 if (args->version == 4)
1880 #ifdef CONFIG_NFS_V4
1881                         return nfs4_validate_text_mount_data(options,
1882                                                              args, dev_name);
1883 #else
1884                         goto out_v4_not_compiled;
1885 #endif
1886
1887                 nfs_set_port(sap, &args->nfs_server.port, 0);
1888
1889                 nfs_set_mount_transport_protocol(args);
1890
1891                 status = nfs_parse_devname(dev_name,
1892                                            &args->nfs_server.hostname,
1893                                            PAGE_SIZE,
1894                                            &args->nfs_server.export_path,
1895                                            NFS_MAXPATHLEN);
1896                 if (!status)
1897                         status = nfs_try_mount(args, mntfh);
1898
1899                 kfree(args->nfs_server.export_path);
1900                 args->nfs_server.export_path = NULL;
1901
1902                 if (status)
1903                         return status;
1904
1905                 break;
1906                 }
1907         }
1908
1909 #ifndef CONFIG_NFS_V3
1910         if (args->version == 3)
1911                 goto out_v3_not_compiled;
1912 #endif /* !CONFIG_NFS_V3 */
1913
1914         return 0;
1915
1916 out_no_data:
1917         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1918         return -EINVAL;
1919
1920 out_no_v3:
1921         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1922                  data->version);
1923         return -EINVAL;
1924
1925 out_no_sec:
1926         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1927         return -EINVAL;
1928
1929 #ifndef CONFIG_NFS_V3
1930 out_v3_not_compiled:
1931         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1932         return -EPROTONOSUPPORT;
1933 #endif /* !CONFIG_NFS_V3 */
1934
1935 #ifndef CONFIG_NFS_V4
1936 out_v4_not_compiled:
1937         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1938         return -EPROTONOSUPPORT;
1939 #endif /* !CONFIG_NFS_V4 */
1940
1941 out_nomem:
1942         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1943         return -ENOMEM;
1944
1945 out_no_address:
1946         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1947         return -EINVAL;
1948
1949 out_invalid_fh:
1950         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1951         return -EINVAL;
1952 }
1953
1954 static int
1955 nfs_compare_remount_data(struct nfs_server *nfss,
1956                          struct nfs_parsed_mount_data *data)
1957 {
1958         if (data->flags != nfss->flags ||
1959             data->rsize != nfss->rsize ||
1960             data->wsize != nfss->wsize ||
1961             data->retrans != nfss->client->cl_timeout->to_retries ||
1962             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1963             data->acregmin != nfss->acregmin / HZ ||
1964             data->acregmax != nfss->acregmax / HZ ||
1965             data->acdirmin != nfss->acdirmin / HZ ||
1966             data->acdirmax != nfss->acdirmax / HZ ||
1967             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1968             data->nfs_server.port != nfss->port ||
1969             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1970             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1971                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1972                 return -EINVAL;
1973
1974         return 0;
1975 }
1976
1977 static int
1978 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1979 {
1980         int error;
1981         struct nfs_server *nfss = sb->s_fs_info;
1982         struct nfs_parsed_mount_data *data;
1983         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1984         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1985         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1986
1987         /*
1988          * Userspace mount programs that send binary options generally send
1989          * them populated with default values. We have no way to know which
1990          * ones were explicitly specified. Fall back to legacy behavior and
1991          * just return success.
1992          */
1993         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1994             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1995                                            options->version <= 6))))
1996                 return 0;
1997
1998         data = kzalloc(sizeof(*data), GFP_KERNEL);
1999         if (data == NULL)
2000                 return -ENOMEM;
2001
2002         /* fill out struct with values from existing mount */
2003         data->flags = nfss->flags;
2004         data->rsize = nfss->rsize;
2005         data->wsize = nfss->wsize;
2006         data->retrans = nfss->client->cl_timeout->to_retries;
2007         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2008         data->acregmin = nfss->acregmin / HZ;
2009         data->acregmax = nfss->acregmax / HZ;
2010         data->acdirmin = nfss->acdirmin / HZ;
2011         data->acdirmax = nfss->acdirmax / HZ;
2012         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2013         data->nfs_server.port = nfss->port;
2014         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2015         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2016                 data->nfs_server.addrlen);
2017
2018         /* overwrite those values with any that were specified */
2019         error = nfs_parse_mount_options((char *)options, data);
2020         if (error < 0)
2021                 goto out;
2022
2023         /*
2024          * noac is a special case. It implies -o sync, but that's not
2025          * necessarily reflected in the mtab options. do_remount_sb
2026          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2027          * remount options, so we have to explicitly reset it.
2028          */
2029         if (data->flags & NFS_MOUNT_NOAC)
2030                 *flags |= MS_SYNCHRONOUS;
2031
2032         /* compare new mount options with old ones */
2033         error = nfs_compare_remount_data(nfss, data);
2034 out:
2035         kfree(data);
2036         return error;
2037 }
2038
2039 /*
2040  * Initialise the common bits of the superblock
2041  */
2042 static inline void nfs_initialise_sb(struct super_block *sb)
2043 {
2044         struct nfs_server *server = NFS_SB(sb);
2045
2046         sb->s_magic = NFS_SUPER_MAGIC;
2047
2048         /* We probably want something more informative here */
2049         snprintf(sb->s_id, sizeof(sb->s_id),
2050                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2051
2052         if (sb->s_blocksize == 0)
2053                 sb->s_blocksize = nfs_block_bits(server->wsize,
2054                                                  &sb->s_blocksize_bits);
2055
2056         sb->s_bdi = &server->backing_dev_info;
2057
2058         nfs_super_set_maxbytes(sb, server->maxfilesize);
2059 }
2060
2061 /*
2062  * Finish setting up an NFS2/3 superblock
2063  */
2064 static void nfs_fill_super(struct super_block *sb,
2065                            struct nfs_parsed_mount_data *data)
2066 {
2067         struct nfs_server *server = NFS_SB(sb);
2068
2069         sb->s_blocksize_bits = 0;
2070         sb->s_blocksize = 0;
2071         if (data->bsize)
2072                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2073
2074         if (server->nfs_client->rpc_ops->version == 3) {
2075                 /* The VFS shouldn't apply the umask to mode bits. We will do
2076                  * so ourselves when necessary.
2077                  */
2078                 sb->s_flags |= MS_POSIXACL;
2079                 sb->s_time_gran = 1;
2080         }
2081
2082         sb->s_op = &nfs_sops;
2083         nfs_initialise_sb(sb);
2084 }
2085
2086 /*
2087  * Finish setting up a cloned NFS2/3 superblock
2088  */
2089 static void nfs_clone_super(struct super_block *sb,
2090                             const struct super_block *old_sb)
2091 {
2092         struct nfs_server *server = NFS_SB(sb);
2093
2094         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2095         sb->s_blocksize = old_sb->s_blocksize;
2096         sb->s_maxbytes = old_sb->s_maxbytes;
2097
2098         if (server->nfs_client->rpc_ops->version == 3) {
2099                 /* The VFS shouldn't apply the umask to mode bits. We will do
2100                  * so ourselves when necessary.
2101                  */
2102                 sb->s_flags |= MS_POSIXACL;
2103                 sb->s_time_gran = 1;
2104         }
2105
2106         sb->s_op = old_sb->s_op;
2107         nfs_initialise_sb(sb);
2108 }
2109
2110 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2111 {
2112         const struct nfs_server *a = s->s_fs_info;
2113         const struct rpc_clnt *clnt_a = a->client;
2114         const struct rpc_clnt *clnt_b = b->client;
2115
2116         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2117                 goto Ebusy;
2118         if (a->nfs_client != b->nfs_client)
2119                 goto Ebusy;
2120         if (a->flags != b->flags)
2121                 goto Ebusy;
2122         if (a->wsize != b->wsize)
2123                 goto Ebusy;
2124         if (a->rsize != b->rsize)
2125                 goto Ebusy;
2126         if (a->acregmin != b->acregmin)
2127                 goto Ebusy;
2128         if (a->acregmax != b->acregmax)
2129                 goto Ebusy;
2130         if (a->acdirmin != b->acdirmin)
2131                 goto Ebusy;
2132         if (a->acdirmax != b->acdirmax)
2133                 goto Ebusy;
2134         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2135                 goto Ebusy;
2136         return 1;
2137 Ebusy:
2138         return 0;
2139 }
2140
2141 struct nfs_sb_mountdata {
2142         struct nfs_server *server;
2143         int mntflags;
2144 };
2145
2146 static int nfs_set_super(struct super_block *s, void *data)
2147 {
2148         struct nfs_sb_mountdata *sb_mntdata = data;
2149         struct nfs_server *server = sb_mntdata->server;
2150         int ret;
2151
2152         s->s_flags = sb_mntdata->mntflags;
2153         s->s_fs_info = server;
2154         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2155         ret = set_anon_super(s, server);
2156         if (ret == 0)
2157                 server->s_dev = s->s_dev;
2158         return ret;
2159 }
2160
2161 static int nfs_compare_super_address(struct nfs_server *server1,
2162                                      struct nfs_server *server2)
2163 {
2164         struct sockaddr *sap1, *sap2;
2165
2166         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2167         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2168
2169         if (sap1->sa_family != sap2->sa_family)
2170                 return 0;
2171
2172         switch (sap1->sa_family) {
2173         case AF_INET: {
2174                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2175                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2176                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2177                         return 0;
2178                 if (sin1->sin_port != sin2->sin_port)
2179                         return 0;
2180                 break;
2181         }
2182         case AF_INET6: {
2183                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2184                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2185                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2186                         return 0;
2187                 if (sin1->sin6_port != sin2->sin6_port)
2188                         return 0;
2189                 break;
2190         }
2191         default:
2192                 return 0;
2193         }
2194
2195         return 1;
2196 }
2197
2198 static int nfs_compare_super(struct super_block *sb, void *data)
2199 {
2200         struct nfs_sb_mountdata *sb_mntdata = data;
2201         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2202         int mntflags = sb_mntdata->mntflags;
2203
2204         if (!nfs_compare_super_address(old, server))
2205                 return 0;
2206         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2207         if (old->flags & NFS_MOUNT_UNSHARED)
2208                 return 0;
2209         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2210                 return 0;
2211         return nfs_compare_mount_options(sb, server, mntflags);
2212 }
2213
2214 static int nfs_bdi_register(struct nfs_server *server)
2215 {
2216         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2217 }
2218
2219 static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2220         int flags, const char *dev_name, void *raw_data)
2221 {
2222         struct nfs_server *server = NULL;
2223         struct super_block *s;
2224         struct nfs_parsed_mount_data *data;
2225         struct nfs_fh *mntfh;
2226         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2227         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2228         struct nfs_sb_mountdata sb_mntdata = {
2229                 .mntflags = flags,
2230         };
2231         int error;
2232
2233         data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
2234         mntfh = nfs_alloc_fhandle();
2235         if (data == NULL || mntfh == NULL)
2236                 goto out;
2237
2238         /* Validate the mount data */
2239         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2240         if (error < 0) {
2241                 mntroot = ERR_PTR(error);
2242                 goto out;
2243         }
2244
2245 #ifdef CONFIG_NFS_V4
2246         if (data->version == 4) {
2247                 mntroot = nfs4_try_mount(flags, dev_name, data);
2248                 goto out;
2249         }
2250 #endif  /* CONFIG_NFS_V4 */
2251
2252         /* Get a volume representation */
2253         server = nfs_create_server(data, mntfh);
2254         if (IS_ERR(server)) {
2255                 mntroot = ERR_CAST(server);
2256                 goto out;
2257         }
2258         sb_mntdata.server = server;
2259
2260         if (server->flags & NFS_MOUNT_UNSHARED)
2261                 compare_super = NULL;
2262
2263         /* -o noac implies -o sync */
2264         if (server->flags & NFS_MOUNT_NOAC)
2265                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2266
2267         /* Get a superblock - note that we may end up sharing one that already exists */
2268         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2269         if (IS_ERR(s)) {
2270                 mntroot = ERR_CAST(s);
2271                 goto out_err_nosb;
2272         }
2273
2274         if (s->s_fs_info != server) {
2275                 nfs_free_server(server);
2276                 server = NULL;
2277         } else {
2278                 error = nfs_bdi_register(server);
2279                 if (error) {
2280                         mntroot = ERR_PTR(error);
2281                         goto error_splat_bdi;
2282                 }
2283         }
2284
2285         if (!s->s_root) {
2286                 /* initial superblock/root creation */
2287                 nfs_fill_super(s, data);
2288                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2289         }
2290
2291         mntroot = nfs_get_root(s, mntfh, dev_name);
2292         if (IS_ERR(mntroot))
2293                 goto error_splat_super;
2294
2295         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2296         if (error)
2297                 goto error_splat_root;
2298
2299         s->s_flags |= MS_ACTIVE;
2300
2301 out:
2302         nfs_free_parsed_mount_data(data);
2303         nfs_free_fhandle(mntfh);
2304         return mntroot;
2305
2306 out_err_nosb:
2307         nfs_free_server(server);
2308         goto out;
2309
2310 error_splat_root:
2311         dput(mntroot);
2312         mntroot = ERR_PTR(error);
2313 error_splat_super:
2314         if (server && !s->s_root)
2315                 bdi_unregister(&server->backing_dev_info);
2316 error_splat_bdi:
2317         deactivate_locked_super(s);
2318         goto out;
2319 }
2320
2321 /*
2322  * Ensure that we unregister the bdi before kill_anon_super
2323  * releases the device name
2324  */
2325 static void nfs_put_super(struct super_block *s)
2326 {
2327         struct nfs_server *server = NFS_SB(s);
2328
2329         bdi_unregister(&server->backing_dev_info);
2330 }
2331
2332 /*
2333  * Destroy an NFS2/3 superblock
2334  */
2335 static void nfs_kill_super(struct super_block *s)
2336 {
2337         struct nfs_server *server = NFS_SB(s);
2338
2339         kill_anon_super(s);
2340         nfs_fscache_release_super_cookie(s);
2341         nfs_free_server(server);
2342 }
2343
2344 /*
2345  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2346  */
2347 static struct dentry *
2348 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2349                 const char *dev_name, void *raw_data)
2350 {
2351         struct nfs_clone_mount *data = raw_data;
2352         struct super_block *s;
2353         struct nfs_server *server;
2354         struct dentry *mntroot;
2355         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2356         struct nfs_sb_mountdata sb_mntdata = {
2357                 .mntflags = flags,
2358         };
2359         int error;
2360
2361         dprintk("--> nfs_xdev_mount()\n");
2362
2363         /* create a new volume representation */
2364         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2365         if (IS_ERR(server)) {
2366                 error = PTR_ERR(server);
2367                 goto out_err_noserver;
2368         }
2369         sb_mntdata.server = server;
2370
2371         if (server->flags & NFS_MOUNT_UNSHARED)
2372                 compare_super = NULL;
2373
2374         /* -o noac implies -o sync */
2375         if (server->flags & NFS_MOUNT_NOAC)
2376                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2377
2378         /* Get a superblock - note that we may end up sharing one that already exists */
2379         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2380         if (IS_ERR(s)) {
2381                 error = PTR_ERR(s);
2382                 goto out_err_nosb;
2383         }
2384
2385         if (s->s_fs_info != server) {
2386                 nfs_free_server(server);
2387                 server = NULL;
2388         } else {
2389                 error = nfs_bdi_register(server);
2390                 if (error)
2391                         goto error_splat_bdi;
2392         }
2393
2394         if (!s->s_root) {
2395                 /* initial superblock/root creation */
2396                 nfs_clone_super(s, data->sb);
2397                 nfs_fscache_get_super_cookie(s, NULL, data);
2398         }
2399
2400         mntroot = nfs_get_root(s, data->fh, dev_name);
2401         if (IS_ERR(mntroot)) {
2402                 error = PTR_ERR(mntroot);
2403                 goto error_splat_super;
2404         }
2405         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2406                 dput(mntroot);
2407                 error = -ESTALE;
2408                 goto error_splat_super;
2409         }
2410
2411         s->s_flags |= MS_ACTIVE;
2412
2413         /* clone any lsm security options from the parent to the new sb */
2414         security_sb_clone_mnt_opts(data->sb, s);
2415
2416         dprintk("<-- nfs_xdev_mount() = 0\n");
2417         return mntroot;
2418
2419 out_err_nosb:
2420         nfs_free_server(server);
2421 out_err_noserver:
2422         dprintk("<-- nfs_xdev_mount() = %d [error]\n", error);
2423         return ERR_PTR(error);
2424
2425 error_splat_super:
2426         if (server && !s->s_root)
2427                 bdi_unregister(&server->backing_dev_info);
2428 error_splat_bdi:
2429         deactivate_locked_super(s);
2430         dprintk("<-- nfs_xdev_mount() = %d [splat]\n", error);
2431         return ERR_PTR(error);
2432 }
2433
2434 #ifdef CONFIG_NFS_V4
2435
2436 /*
2437  * Finish setting up a cloned NFS4 superblock
2438  */
2439 static void nfs4_clone_super(struct super_block *sb,
2440                             const struct super_block *old_sb)
2441 {
2442         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2443         sb->s_blocksize = old_sb->s_blocksize;
2444         sb->s_maxbytes = old_sb->s_maxbytes;
2445         sb->s_time_gran = 1;
2446         sb->s_op = old_sb->s_op;
2447         /*
2448          * The VFS shouldn't apply the umask to mode bits. We will do
2449          * so ourselves when necessary.
2450          */
2451         sb->s_flags  |= MS_POSIXACL;
2452         sb->s_xattr  = old_sb->s_xattr;
2453         nfs_initialise_sb(sb);
2454 }
2455
2456 /*
2457  * Set up an NFS4 superblock
2458  */
2459 static void nfs4_fill_super(struct super_block *sb)
2460 {
2461         sb->s_time_gran = 1;
2462         sb->s_op = &nfs4_sops;
2463         /*
2464          * The VFS shouldn't apply the umask to mode bits. We will do
2465          * so ourselves when necessary.
2466          */
2467         sb->s_flags  |= MS_POSIXACL;
2468         sb->s_xattr = nfs4_xattr_handlers;
2469         nfs_initialise_sb(sb);
2470 }
2471
2472 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2473 {
2474         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2475                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2476 }
2477
2478 static int nfs4_validate_text_mount_data(void *options,
2479                                          struct nfs_parsed_mount_data *args,
2480                                          const char *dev_name)
2481 {
2482         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2483
2484         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2485
2486         nfs_validate_transport_protocol(args);
2487
2488         nfs4_validate_mount_flags(args);
2489
2490         if (args->version != 4) {
2491                 dfprintk(MOUNT,
2492                          "NFS4: Illegal mount version\n");
2493                 return -EINVAL;
2494         }
2495
2496         if (args->auth_flavor_len > 1) {
2497                 dfprintk(MOUNT,
2498                          "NFS4: Too many RPC auth flavours specified\n");
2499                 return -EINVAL;
2500         }
2501
2502         if (args->client_address == NULL) {
2503                 dfprintk(MOUNT,
2504                          "NFS4: mount program didn't pass callback address\n");
2505                 return -EINVAL;
2506         }
2507
2508         return nfs_parse_devname(dev_name,
2509                                    &args->nfs_server.hostname,
2510                                    NFS4_MAXNAMLEN,
2511                                    &args->nfs_server.export_path,
2512                                    NFS4_MAXPATHLEN);
2513 }
2514
2515 /*
2516  * Validate NFSv4 mount options
2517  */
2518 static int nfs4_validate_mount_data(void *options,
2519                                     struct nfs_parsed_mount_data *args,
2520                                     const char *dev_name)
2521 {
2522         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2523         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2524         char *c;
2525
2526         if (data == NULL)
2527                 goto out_no_data;
2528
2529         switch (data->version) {
2530         case 1:
2531                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2532                         goto out_no_address;
2533                 if (data->host_addrlen == 0)
2534                         goto out_no_address;
2535                 args->nfs_server.addrlen = data->host_addrlen;
2536                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2537                         return -EFAULT;
2538                 if (!nfs_verify_server_address(sap))
2539                         goto out_no_address;
2540
2541                 if (data->auth_flavourlen) {
2542                         if (data->auth_flavourlen > 1)
2543                                 goto out_inval_auth;
2544                         if (copy_from_user(&args->auth_flavors[0],
2545                                            data->auth_flavours,
2546                                            sizeof(args->auth_flavors[0])))
2547                                 return -EFAULT;
2548                 }
2549
2550                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2551                 if (IS_ERR(c))
2552                         return PTR_ERR(c);
2553                 args->nfs_server.hostname = c;
2554
2555                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2556                 if (IS_ERR(c))
2557                         return PTR_ERR(c);
2558                 args->nfs_server.export_path = c;
2559                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2560
2561                 c = strndup_user(data->client_addr.data, 16);
2562                 if (IS_ERR(c))
2563                         return PTR_ERR(c);
2564                 args->client_address = c;
2565
2566                 /*
2567                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2568                  * can deal with.
2569                  */
2570
2571                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2572                 args->rsize     = data->rsize;
2573                 args->wsize     = data->wsize;
2574                 args->timeo     = data->timeo;
2575                 args->retrans   = data->retrans;
2576                 args->acregmin  = data->acregmin;
2577                 args->acregmax  = data->acregmax;
2578                 args->acdirmin  = data->acdirmin;
2579                 args->acdirmax  = data->acdirmax;
2580                 args->nfs_server.protocol = data->proto;
2581                 nfs_validate_transport_protocol(args);
2582
2583                 break;
2584         default:
2585                 if (nfs_parse_mount_options((char *)options, args) == 0)
2586                         return -EINVAL;
2587
2588                 if (!nfs_verify_server_address(sap))
2589                         return -EINVAL;
2590
2591                 return nfs4_validate_text_mount_data(options, args, dev_name);
2592         }
2593
2594         return 0;
2595
2596 out_no_data:
2597         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2598         return -EINVAL;
2599
2600 out_inval_auth:
2601         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2602                  data->auth_flavourlen);
2603         return -EINVAL;
2604
2605 out_no_address:
2606         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2607         return -EINVAL;
2608 }
2609
2610 /*
2611  * Get the superblock for the NFS4 root partition
2612  */
2613 static struct dentry *
2614 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
2615                   const char *dev_name, void *raw_data)
2616 {
2617         struct nfs_parsed_mount_data *data = raw_data;
2618         struct super_block *s;
2619         struct nfs_server *server;
2620         struct nfs_fh *mntfh;
2621         struct dentry *mntroot;
2622         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2623         struct nfs_sb_mountdata sb_mntdata = {
2624                 .mntflags = flags,
2625         };
2626         int error = -ENOMEM;
2627
2628         mntfh = nfs_alloc_fhandle();
2629         if (data == NULL || mntfh == NULL)
2630                 goto out;
2631
2632         /* Get a volume representation */
2633         server = nfs4_create_server(data, mntfh);
2634         if (IS_ERR(server)) {
2635                 error = PTR_ERR(server);
2636                 goto out;
2637         }
2638         sb_mntdata.server = server;
2639
2640         if (server->flags & NFS4_MOUNT_UNSHARED)
2641                 compare_super = NULL;
2642
2643         /* -o noac implies -o sync */
2644         if (server->flags & NFS_MOUNT_NOAC)
2645                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2646
2647         /* Get a superblock - note that we may end up sharing one that already exists */
2648         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2649         if (IS_ERR(s)) {
2650                 error = PTR_ERR(s);
2651                 goto out_free;
2652         }
2653
2654         if (s->s_fs_info != server) {
2655                 nfs_free_server(server);
2656                 server = NULL;
2657         } else {
2658                 error = nfs_bdi_register(server);
2659                 if (error)
2660                         goto error_splat_bdi;
2661         }
2662
2663         if (!s->s_root) {
2664                 /* initial superblock/root creation */
2665                 nfs4_fill_super(s);
2666                 nfs_fscache_get_super_cookie(
2667                         s, data ? data->fscache_uniq : NULL, NULL);
2668         }
2669
2670         mntroot = nfs4_get_root(s, mntfh, dev_name);
2671         if (IS_ERR(mntroot)) {
2672                 error = PTR_ERR(mntroot);
2673                 goto error_splat_super;
2674         }
2675
2676         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2677         if (error)
2678                 goto error_splat_root;
2679
2680         s->s_flags |= MS_ACTIVE;
2681
2682         nfs_free_fhandle(mntfh);
2683         return mntroot;
2684
2685 out:
2686         nfs_free_fhandle(mntfh);
2687         return ERR_PTR(error);
2688
2689 out_free:
2690         nfs_free_server(server);
2691         goto out;
2692
2693 error_splat_root:
2694         dput(mntroot);
2695 error_splat_super:
2696         if (server && !s->s_root)
2697                 bdi_unregister(&server->backing_dev_info);
2698 error_splat_bdi:
2699         deactivate_locked_super(s);
2700         goto out;
2701 }
2702
2703 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2704                 int flags, void *data, const char *hostname)
2705 {
2706         struct vfsmount *root_mnt;
2707         char *root_devname;
2708         size_t len;
2709
2710         len = strlen(hostname) + 3;
2711         root_devname = kmalloc(len, GFP_KERNEL);
2712         if (root_devname == NULL)
2713                 return ERR_PTR(-ENOMEM);
2714         snprintf(root_devname, len, "%s:/", hostname);
2715         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2716         kfree(root_devname);
2717         return root_mnt;
2718 }
2719
2720 struct nfs_referral_count {
2721         struct list_head list;
2722         const struct task_struct *task;
2723         unsigned int referral_count;
2724 };
2725
2726 static LIST_HEAD(nfs_referral_count_list);
2727 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2728
2729 static struct nfs_referral_count *nfs_find_referral_count(void)
2730 {
2731         struct nfs_referral_count *p;
2732
2733         list_for_each_entry(p, &nfs_referral_count_list, list) {
2734                 if (p->task == current)
2735                         return p;
2736         }
2737         return NULL;
2738 }
2739
2740 #define NFS_MAX_NESTED_REFERRALS 2
2741
2742 static int nfs_referral_loop_protect(void)
2743 {
2744         struct nfs_referral_count *p, *new;
2745         int ret = -ENOMEM;
2746
2747         new = kmalloc(sizeof(*new), GFP_KERNEL);
2748         if (!new)
2749                 goto out;
2750         new->task = current;
2751         new->referral_count = 1;
2752
2753         ret = 0;
2754         spin_lock(&nfs_referral_count_list_lock);
2755         p = nfs_find_referral_count();
2756         if (p != NULL) {
2757                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2758                         ret = -ELOOP;
2759                 else
2760                         p->referral_count++;
2761         } else {
2762                 list_add(&new->list, &nfs_referral_count_list);
2763                 new = NULL;
2764         }
2765         spin_unlock(&nfs_referral_count_list_lock);
2766         kfree(new);
2767 out:
2768         return ret;
2769 }
2770
2771 static void nfs_referral_loop_unprotect(void)
2772 {
2773         struct nfs_referral_count *p;
2774
2775         spin_lock(&nfs_referral_count_list_lock);
2776         p = nfs_find_referral_count();
2777         p->referral_count--;
2778         if (p->referral_count == 0)
2779                 list_del(&p->list);
2780         else
2781                 p = NULL;
2782         spin_unlock(&nfs_referral_count_list_lock);
2783         kfree(p);
2784 }
2785
2786 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
2787                 const char *export_path)
2788 {
2789         struct dentry *dentry;
2790         int err;
2791
2792         if (IS_ERR(root_mnt))
2793                 return ERR_CAST(root_mnt);
2794
2795         err = nfs_referral_loop_protect();
2796         if (err) {
2797                 mntput(root_mnt);
2798                 return ERR_PTR(err);
2799         }
2800
2801         dentry = mount_subtree(root_mnt, export_path);
2802         nfs_referral_loop_unprotect();
2803
2804         return dentry;
2805 }
2806
2807 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
2808                          struct nfs_parsed_mount_data *data)
2809 {
2810         char *export_path;
2811         struct vfsmount *root_mnt;
2812         struct dentry *res;
2813
2814         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2815
2816         export_path = data->nfs_server.export_path;
2817         data->nfs_server.export_path = "/";
2818         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2819                         data->nfs_server.hostname);
2820         data->nfs_server.export_path = export_path;
2821
2822         res = nfs_follow_remote_path(root_mnt, export_path);
2823
2824         dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
2825                         IS_ERR(res) ? PTR_ERR(res) : 0,
2826                         IS_ERR(res) ? " [error]" : "");
2827         return res;
2828 }
2829
2830 /*
2831  * Get the superblock for an NFS4 mountpoint
2832  */
2833 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
2834         int flags, const char *dev_name, void *raw_data)
2835 {
2836         struct nfs_parsed_mount_data *data;
2837         int error = -ENOMEM;
2838         struct dentry *res = ERR_PTR(-ENOMEM);
2839
2840         data = nfs_alloc_parsed_mount_data(4);
2841         if (data == NULL)
2842                 goto out;
2843
2844         /* Validate the mount data */
2845         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2846         if (error < 0) {
2847                 res = ERR_PTR(error);
2848                 goto out;
2849         }
2850
2851         res = nfs4_try_mount(flags, dev_name, data);
2852         if (IS_ERR(res))
2853                 error = PTR_ERR(res);
2854
2855 out:
2856         nfs_free_parsed_mount_data(data);
2857         dprintk("<-- nfs4_mount() = %d%s\n", error,
2858                         error != 0 ? " [error]" : "");
2859         return res;
2860 }
2861
2862 static void nfs4_kill_super(struct super_block *sb)
2863 {
2864         struct nfs_server *server = NFS_SB(sb);
2865
2866         dprintk("--> %s\n", __func__);
2867         nfs_super_return_all_delegations(sb);
2868         kill_anon_super(sb);
2869         nfs_fscache_release_super_cookie(sb);
2870         nfs_free_server(server);
2871         dprintk("<-- %s\n", __func__);
2872 }
2873
2874 /*
2875  * Clone an NFS4 server record on xdev traversal (FSID-change)
2876  */
2877 static struct dentry *
2878 nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
2879                  const char *dev_name, void *raw_data)
2880 {
2881         struct nfs_clone_mount *data = raw_data;
2882         struct super_block *s;
2883         struct nfs_server *server;
2884         struct dentry *mntroot;
2885         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2886         struct nfs_sb_mountdata sb_mntdata = {
2887                 .mntflags = flags,
2888         };
2889         int error;
2890
2891         dprintk("--> nfs4_xdev_mount()\n");
2892
2893         /* create a new volume representation */
2894         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2895         if (IS_ERR(server)) {
2896                 error = PTR_ERR(server);
2897                 goto out_err_noserver;
2898         }
2899         sb_mntdata.server = server;
2900
2901         if (server->flags & NFS4_MOUNT_UNSHARED)
2902                 compare_super = NULL;
2903
2904         /* -o noac implies -o sync */
2905         if (server->flags & NFS_MOUNT_NOAC)
2906                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2907
2908         /* Get a superblock - note that we may end up sharing one that already exists */
2909         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2910         if (IS_ERR(s)) {
2911                 error = PTR_ERR(s);
2912                 goto out_err_nosb;
2913         }
2914
2915         if (s->s_fs_info != server) {
2916                 nfs_free_server(server);
2917                 server = NULL;
2918         } else {
2919                 error = nfs_bdi_register(server);
2920                 if (error)
2921                         goto error_splat_bdi;
2922         }
2923
2924         if (!s->s_root) {
2925                 /* initial superblock/root creation */
2926                 nfs4_clone_super(s, data->sb);
2927                 nfs_fscache_get_super_cookie(s, NULL, data);
2928         }
2929
2930         mntroot = nfs4_get_root(s, data->fh, dev_name);
2931         if (IS_ERR(mntroot)) {
2932                 error = PTR_ERR(mntroot);
2933                 goto error_splat_super;
2934         }
2935         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2936                 dput(mntroot);
2937                 error = -ESTALE;
2938                 goto error_splat_super;
2939         }
2940
2941         s->s_flags |= MS_ACTIVE;
2942
2943         security_sb_clone_mnt_opts(data->sb, s);
2944
2945         dprintk("<-- nfs4_xdev_mount() = 0\n");
2946         return mntroot;
2947
2948 out_err_nosb:
2949         nfs_free_server(server);
2950 out_err_noserver:
2951         dprintk("<-- nfs4_xdev_mount() = %d [error]\n", error);
2952         return ERR_PTR(error);
2953
2954 error_splat_super:
2955         if (server && !s->s_root)
2956                 bdi_unregister(&server->backing_dev_info);
2957 error_splat_bdi:
2958         deactivate_locked_super(s);
2959         dprintk("<-- nfs4_xdev_mount() = %d [splat]\n", error);
2960         return ERR_PTR(error);
2961 }
2962
2963 static struct dentry *
2964 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
2965                            const char *dev_name, void *raw_data)
2966 {
2967         struct nfs_clone_mount *data = raw_data;
2968         struct super_block *s;
2969         struct nfs_server *server;
2970         struct dentry *mntroot;
2971         struct nfs_fh *mntfh;
2972         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2973         struct nfs_sb_mountdata sb_mntdata = {
2974                 .mntflags = flags,
2975         };
2976         int error = -ENOMEM;
2977
2978         dprintk("--> nfs4_referral_get_sb()\n");
2979
2980         mntfh = nfs_alloc_fhandle();
2981         if (mntfh == NULL)
2982                 goto out_err_nofh;
2983
2984         /* create a new volume representation */
2985         server = nfs4_create_referral_server(data, mntfh);
2986         if (IS_ERR(server)) {
2987                 error = PTR_ERR(server);
2988                 goto out_err_noserver;
2989         }
2990         sb_mntdata.server = server;
2991
2992         if (server->flags & NFS4_MOUNT_UNSHARED)
2993                 compare_super = NULL;
2994
2995         /* -o noac implies -o sync */
2996         if (server->flags & NFS_MOUNT_NOAC)
2997                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2998
2999         /* Get a superblock - note that we may end up sharing one that already exists */
3000         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
3001         if (IS_ERR(s)) {
3002                 error = PTR_ERR(s);
3003                 goto out_err_nosb;
3004         }
3005
3006         if (s->s_fs_info != server) {
3007                 nfs_free_server(server);
3008                 server = NULL;
3009         } else {
3010                 error = nfs_bdi_register(server);
3011                 if (error)
3012                         goto error_splat_bdi;
3013         }
3014
3015         if (!s->s_root) {
3016                 /* initial superblock/root creation */
3017                 nfs4_fill_super(s);
3018                 nfs_fscache_get_super_cookie(s, NULL, data);
3019         }
3020
3021         mntroot = nfs4_get_root(s, mntfh, dev_name);
3022         if (IS_ERR(mntroot)) {
3023                 error = PTR_ERR(mntroot);
3024                 goto error_splat_super;
3025         }
3026         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3027                 dput(mntroot);
3028                 error = -ESTALE;
3029                 goto error_splat_super;
3030         }
3031
3032         s->s_flags |= MS_ACTIVE;
3033
3034         security_sb_clone_mnt_opts(data->sb, s);
3035
3036         nfs_free_fhandle(mntfh);
3037         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3038         return mntroot;
3039
3040 out_err_nosb:
3041         nfs_free_server(server);
3042 out_err_noserver:
3043         nfs_free_fhandle(mntfh);
3044 out_err_nofh:
3045         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3046         return ERR_PTR(error);
3047
3048 error_splat_super:
3049         if (server && !s->s_root)
3050                 bdi_unregister(&server->backing_dev_info);
3051 error_splat_bdi:
3052         deactivate_locked_super(s);
3053         nfs_free_fhandle(mntfh);
3054         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3055         return ERR_PTR(error);
3056 }
3057
3058 /*
3059  * Create an NFS4 server record on referral traversal
3060  */
3061 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
3062                 int flags, const char *dev_name, void *raw_data)
3063 {
3064         struct nfs_clone_mount *data = raw_data;
3065         char *export_path;
3066         struct vfsmount *root_mnt;
3067         struct dentry *res;
3068
3069         dprintk("--> nfs4_referral_mount()\n");
3070
3071         export_path = data->mnt_path;
3072         data->mnt_path = "/";
3073
3074         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3075                         flags, data, data->hostname);
3076         data->mnt_path = export_path;
3077
3078         res = nfs_follow_remote_path(root_mnt, export_path);
3079         dprintk("<-- nfs4_referral_mount() = %ld%s\n",
3080                         IS_ERR(res) ? PTR_ERR(res) : 0,
3081                         IS_ERR(res) ? " [error]" : "");
3082         return res;
3083 }
3084
3085 #endif /* CONFIG_NFS_V4 */