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 #include <linux/nsproxy.h>
  56 #include <linux/rcupdate.h>
  57
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "pnfs.h"
  67 #include "nfs.h"
  68
  69 #define NFSDBG_FACILITY         NFSDBG_VFS
  70 #define NFS_TEXT_DATA           1
  71
  72 #ifdef CONFIG_NFS_V3
  73 #define NFS_DEFAULT_VERSION 3
  74 #else
  75 #define NFS_DEFAULT_VERSION 2
  76 #endif
  77
  78 enum {
  79         /* Mount options that take no arguments */
  80         Opt_soft, Opt_hard,
  81         Opt_posix, Opt_noposix,
  82         Opt_cto, Opt_nocto,
  83         Opt_ac, Opt_noac,
  84         Opt_lock, Opt_nolock,
  85         Opt_udp, Opt_tcp, Opt_rdma,
  86         Opt_acl, Opt_noacl,
  87         Opt_rdirplus, Opt_nordirplus,
  88         Opt_sharecache, Opt_nosharecache,
  89         Opt_resvport, Opt_noresvport,
  90         Opt_fscache, Opt_nofscache,
  91
  92         /* Mount options that take integer arguments */
  93         Opt_port,
  94         Opt_rsize, Opt_wsize, Opt_bsize,
  95         Opt_timeo, Opt_retrans,
  96         Opt_acregmin, Opt_acregmax,
  97         Opt_acdirmin, Opt_acdirmax,
  98         Opt_actimeo,
  99         Opt_namelen,
 100         Opt_mountport,
 101         Opt_mountvers,
 102         Opt_minorversion,
 103
 104         /* Mount options that take string arguments */
 105         Opt_nfsvers,
 106         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 107         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 108         Opt_lookupcache,
 109         Opt_fscache_uniq,
 110         Opt_local_lock,
 111
 112         /* Special mount options */
 113         Opt_userspace, Opt_deprecated, Opt_sloppy,
 114
 115         Opt_err
 116 };
 117
 118 static const match_table_t nfs_mount_option_tokens = {
 119         { Opt_userspace, "bg" },
 120         { Opt_userspace, "fg" },
 121         { Opt_userspace, "retry=%s" },
 122
 123         { Opt_sloppy, "sloppy" },
 124
 125         { Opt_soft, "soft" },
 126         { Opt_hard, "hard" },
 127         { Opt_deprecated, "intr" },
 128         { Opt_deprecated, "nointr" },
 129         { Opt_posix, "posix" },
 130         { Opt_noposix, "noposix" },
 131         { Opt_cto, "cto" },
 132         { Opt_nocto, "nocto" },
 133         { Opt_ac, "ac" },
 134         { Opt_noac, "noac" },
 135         { Opt_lock, "lock" },
 136         { Opt_nolock, "nolock" },
 137         { Opt_udp, "udp" },
 138         { Opt_tcp, "tcp" },
 139         { Opt_rdma, "rdma" },
 140         { Opt_acl, "acl" },
 141         { Opt_noacl, "noacl" },
 142         { Opt_rdirplus, "rdirplus" },
 143         { Opt_nordirplus, "nordirplus" },
 144         { Opt_sharecache, "sharecache" },
 145         { Opt_nosharecache, "nosharecache" },
 146         { Opt_resvport, "resvport" },
 147         { Opt_noresvport, "noresvport" },
 148         { Opt_fscache, "fsc" },
 149         { Opt_nofscache, "nofsc" },
 150
 151         { Opt_port, "port=%s" },
 152         { Opt_rsize, "rsize=%s" },
 153         { Opt_wsize, "wsize=%s" },
 154         { Opt_bsize, "bsize=%s" },
 155         { Opt_timeo, "timeo=%s" },
 156         { Opt_retrans, "retrans=%s" },
 157         { Opt_acregmin, "acregmin=%s" },
 158         { Opt_acregmax, "acregmax=%s" },
 159         { Opt_acdirmin, "acdirmin=%s" },
 160         { Opt_acdirmax, "acdirmax=%s" },
 161         { Opt_actimeo, "actimeo=%s" },
 162         { Opt_namelen, "namlen=%s" },
 163         { Opt_mountport, "mountport=%s" },
 164         { Opt_mountvers, "mountvers=%s" },
 165         { Opt_minorversion, "minorversion=%s" },
 166
 167         { Opt_nfsvers, "nfsvers=%s" },
 168         { Opt_nfsvers, "vers=%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         /* The following needs to be listed after all other options */
 183         { Opt_nfsvers, "v%s" },
 184
 185         { Opt_err, NULL }
 186 };
 187
 188 enum {
 189         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 190
 191         Opt_xprt_err
 192 };
 193
 194 static const match_table_t nfs_xprt_protocol_tokens = {
 195         { Opt_xprt_udp, "udp" },
 196         { Opt_xprt_udp6, "udp6" },
 197         { Opt_xprt_tcp, "tcp" },
 198         { Opt_xprt_tcp6, "tcp6" },
 199         { Opt_xprt_rdma, "rdma" },
 200
 201         { Opt_xprt_err, NULL }
 202 };
 203
 204 enum {
 205         Opt_sec_none, Opt_sec_sys,
 206         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 207         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 208         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 209
 210         Opt_sec_err
 211 };
 212
 213 static const match_table_t nfs_secflavor_tokens = {
 214         { Opt_sec_none, "none" },
 215         { Opt_sec_none, "null" },
 216         { Opt_sec_sys, "sys" },
 217
 218         { Opt_sec_krb5, "krb5" },
 219         { Opt_sec_krb5i, "krb5i" },
 220         { Opt_sec_krb5p, "krb5p" },
 221
 222         { Opt_sec_lkey, "lkey" },
 223         { Opt_sec_lkeyi, "lkeyi" },
 224         { Opt_sec_lkeyp, "lkeyp" },
 225
 226         { Opt_sec_spkm, "spkm3" },
 227         { Opt_sec_spkmi, "spkm3i" },
 228         { Opt_sec_spkmp, "spkm3p" },
 229
 230         { Opt_sec_err, NULL }
 231 };
 232
 233 enum {
 234         Opt_lookupcache_all, Opt_lookupcache_positive,
 235         Opt_lookupcache_none,
 236
 237         Opt_lookupcache_err
 238 };
 239
 240 static match_table_t nfs_lookupcache_tokens = {
 241         { Opt_lookupcache_all, "all" },
 242         { Opt_lookupcache_positive, "pos" },
 243         { Opt_lookupcache_positive, "positive" },
 244         { Opt_lookupcache_none, "none" },
 245
 246         { Opt_lookupcache_err, NULL }
 247 };
 248
 249 enum {
 250         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 251         Opt_local_lock_none,
 252
 253         Opt_local_lock_err
 254 };
 255
 256 static match_table_t nfs_local_lock_tokens = {
 257         { Opt_local_lock_all, "all" },
 258         { Opt_local_lock_flock, "flock" },
 259         { Opt_local_lock_posix, "posix" },
 260         { Opt_local_lock_none, "none" },
 261
 262         { Opt_local_lock_err, NULL }
 263 };
 264
 265 enum {
 266         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 267         Opt_vers_4_1,
 268
 269         Opt_vers_err
 270 };
 271
 272 static match_table_t nfs_vers_tokens = {
 273         { Opt_vers_2, "2" },
 274         { Opt_vers_3, "3" },
 275         { Opt_vers_4, "4" },
 276         { Opt_vers_4_0, "4.0" },
 277         { Opt_vers_4_1, "4.1" },
 278
 279         { Opt_vers_err, NULL }
 280 };
 281
 282 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 283                 int flags, const char *dev_name, void *raw_data);
 284
 285 struct file_system_type nfs_fs_type = {
 286         .owner          = THIS_MODULE,
 287         .name           = "nfs",
 288         .mount          = nfs_fs_mount,
 289         .kill_sb        = nfs_kill_super,
 290         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 291 };
 292
 293 struct file_system_type nfs_xdev_fs_type = {
 294         .owner          = THIS_MODULE,
 295         .name           = "nfs",
 296         .mount          = nfs_xdev_mount,
 297         .kill_sb        = nfs_kill_super,
 298         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 299 };
 300
 301 const struct super_operations nfs_sops = {
 302         .alloc_inode    = nfs_alloc_inode,
 303         .destroy_inode  = nfs_destroy_inode,
 304         .write_inode    = nfs_write_inode,
 305         .put_super      = nfs_put_super,
 306         .statfs         = nfs_statfs,
 307         .evict_inode    = nfs_evict_inode,
 308         .umount_begin   = nfs_umount_begin,
 309         .show_options   = nfs_show_options,
 310         .show_devname   = nfs_show_devname,
 311         .show_path      = nfs_show_path,
 312         .show_stats     = nfs_show_stats,
 313         .remount_fs     = nfs_remount,
 314 };
 315
 316 #ifdef CONFIG_NFS_V4
 317 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 318 static int nfs4_validate_mount_data(void *options,
 319         struct nfs_parsed_mount_data *args, const char *dev_name);
 320 #endif
 321
 322 static struct shrinker acl_shrinker = {
 323         .shrink         = nfs_access_cache_shrinker,
 324         .seeks          = DEFAULT_SEEKS,
 325 };
 326
 327 /*
 328  * Register the NFS filesystems
 329  */
 330 int __init register_nfs_fs(void)
 331 {
 332         int ret;
 333
 334         ret = register_filesystem(&nfs_fs_type);
 335         if (ret < 0)
 336                 goto error_0;
 337
 338         ret = nfs_register_sysctl();
 339         if (ret < 0)
 340                 goto error_1;
 341         register_shrinker(&acl_shrinker);
 342         return 0;
 343
 344 error_1:
 345         unregister_filesystem(&nfs_fs_type);
 346 error_0:
 347         return ret;
 348 }
 349
 350 /*
 351  * Unregister the NFS filesystems
 352  */
 353 void __exit unregister_nfs_fs(void)
 354 {
 355         unregister_shrinker(&acl_shrinker);
 356         nfs_unregister_sysctl();
 357         unregister_filesystem(&nfs_fs_type);
 358 }
 359
 360 void nfs_sb_active(struct super_block *sb)
 361 {
 362         struct nfs_server *server = NFS_SB(sb);
 363
 364         if (atomic_inc_return(&server->active) == 1)
 365                 atomic_inc(&sb->s_active);
 366 }
 367
 368 void nfs_sb_deactive(struct super_block *sb)
 369 {
 370         struct nfs_server *server = NFS_SB(sb);
 371
 372         if (atomic_dec_and_test(&server->active))
 373                 deactivate_super(sb);
 374 }
 375
 376 /*
 377  * Deliver file system statistics to userspace
 378  */
 379 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 380 {
 381         struct nfs_server *server = NFS_SB(dentry->d_sb);
 382         unsigned char blockbits;
 383         unsigned long blockres;
 384         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 385         struct nfs_fsstat res;
 386         int error = -ENOMEM;
 387
 388         res.fattr = nfs_alloc_fattr();
 389         if (res.fattr == NULL)
 390                 goto out_err;
 391
 392         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 393         if (unlikely(error == -ESTALE)) {
 394                 struct dentry *pd_dentry;
 395
 396                 pd_dentry = dget_parent(dentry);
 397                 if (pd_dentry != NULL) {
 398                         nfs_zap_caches(pd_dentry->d_inode);
 399                         dput(pd_dentry);
 400                 }
 401         }
 402         nfs_free_fattr(res.fattr);
 403         if (error < 0)
 404                 goto out_err;
 405
 406         buf->f_type = NFS_SUPER_MAGIC;
 407
 408         /*
 409          * Current versions of glibc do not correctly handle the
 410          * case where f_frsize != f_bsize.  Eventually we want to
 411          * report the value of wtmult in this field.
 412          */
 413         buf->f_frsize = dentry->d_sb->s_blocksize;
 414
 415         /*
 416          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 417          * are reported in units of f_frsize.  Linux hasn't had
 418          * an f_frsize field in its statfs struct until recently,
 419          * thus historically Linux's sys_statfs reports these
 420          * fields in units of f_bsize.
 421          */
 422         buf->f_bsize = dentry->d_sb->s_blocksize;
 423         blockbits = dentry->d_sb->s_blocksize_bits;
 424         blockres = (1 << blockbits) - 1;
 425         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 426         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 427         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 428
 429         buf->f_files = res.tfiles;
 430         buf->f_ffree = res.afiles;
 431
 432         buf->f_namelen = server->namelen;
 433
 434         return 0;
 435
 436  out_err:
 437         dprintk("%s: statfs error = %d\n", __func__, -error);
 438         return error;
 439 }
 440
 441 /*
 442  * Map the security flavour number to a name
 443  */
 444 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 445 {
 446         static const struct {
 447                 rpc_authflavor_t flavour;
 448                 const char *str;
 449         } sec_flavours[] = {
 450                 { RPC_AUTH_NULL, "null" },
 451                 { RPC_AUTH_UNIX, "sys" },
 452                 { RPC_AUTH_GSS_KRB5, "krb5" },
 453                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 454                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 455                 { RPC_AUTH_GSS_LKEY, "lkey" },
 456                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 457                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 458                 { RPC_AUTH_GSS_SPKM, "spkm" },
 459                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 460                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 461                 { UINT_MAX, "unknown" }
 462         };
 463         int i;
 464
 465         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 466                 if (sec_flavours[i].flavour == flavour)
 467                         break;
 468         }
 469         return sec_flavours[i].str;
 470 }
 471
 472 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 473                                   int showdefaults)
 474 {
 475         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 476
 477         seq_printf(m, ",mountproto=");
 478         switch (sap->sa_family) {
 479         case AF_INET:
 480                 switch (nfss->mountd_protocol) {
 481                 case IPPROTO_UDP:
 482                         seq_printf(m, RPCBIND_NETID_UDP);
 483                         break;
 484                 case IPPROTO_TCP:
 485                         seq_printf(m, RPCBIND_NETID_TCP);
 486                         break;
 487                 default:
 488                         if (showdefaults)
 489                                 seq_printf(m, "auto");
 490                 }
 491                 break;
 492         case AF_INET6:
 493                 switch (nfss->mountd_protocol) {
 494                 case IPPROTO_UDP:
 495                         seq_printf(m, RPCBIND_NETID_UDP6);
 496                         break;
 497                 case IPPROTO_TCP:
 498                         seq_printf(m, RPCBIND_NETID_TCP6);
 499                         break;
 500                 default:
 501                         if (showdefaults)
 502                                 seq_printf(m, "auto");
 503                 }
 504                 break;
 505         default:
 506                 if (showdefaults)
 507                         seq_printf(m, "auto");
 508         }
 509 }
 510
 511 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 512                                     int showdefaults)
 513 {
 514         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 515
 516         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 517                 return;
 518
 519         switch (sap->sa_family) {
 520         case AF_INET: {
 521                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 522                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 523                 break;
 524         }
 525         case AF_INET6: {
 526                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 527                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 528                 break;
 529         }
 530         default:
 531                 if (showdefaults)
 532                         seq_printf(m, ",mountaddr=unspecified");
 533         }
 534
 535         if (nfss->mountd_version || showdefaults)
 536                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 537         if ((nfss->mountd_port &&
 538                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 539                 showdefaults)
 540                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 541
 542         nfs_show_mountd_netid(m, nfss, showdefaults);
 543 }
 544
 545 #ifdef CONFIG_NFS_V4
 546 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 547                                     int showdefaults)
 548 {
 549         struct nfs_client *clp = nfss->nfs_client;
 550
 551         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 552 }
 553 #else
 554 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 555                                     int showdefaults)
 556 {
 557 }
 558 #endif
 559
 560 static void nfs_show_nfs_version(struct seq_file *m,
 561                 unsigned int version,
 562                 unsigned int minorversion)
 563 {
 564         seq_printf(m, ",vers=%u", version);
 565         if (version == 4)
 566                 seq_printf(m, ".%u", minorversion);
 567 }
 568
 569 /*
 570  * Describe the mount options in force on this server representation
 571  */
 572 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 573                                    int showdefaults)
 574 {
 575         static const struct proc_nfs_info {
 576                 int flag;
 577                 const char *str;
 578                 const char *nostr;
 579         } nfs_info[] = {
 580                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 581                 { NFS_MOUNT_POSIX, ",posix", "" },
 582                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 583                 { NFS_MOUNT_NOAC, ",noac", "" },
 584                 { NFS_MOUNT_NONLM, ",nolock", "" },
 585                 { NFS_MOUNT_NOACL, ",noacl", "" },
 586                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 587                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 588                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 589                 { 0, NULL, NULL }
 590         };
 591         const struct proc_nfs_info *nfs_infop;
 592         struct nfs_client *clp = nfss->nfs_client;
 593         u32 version = clp->rpc_ops->version;
 594         int local_flock, local_fcntl;
 595
 596         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 597         seq_printf(m, ",rsize=%u", nfss->rsize);
 598         seq_printf(m, ",wsize=%u", nfss->wsize);
 599         if (nfss->bsize != 0)
 600                 seq_printf(m, ",bsize=%u", nfss->bsize);
 601         seq_printf(m, ",namlen=%u", nfss->namelen);
 602         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 603                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 604         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 605                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 606         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 607                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 608         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 609                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 610         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 611                 if (nfss->flags & nfs_infop->flag)
 612                         seq_puts(m, nfs_infop->str);
 613                 else
 614                         seq_puts(m, nfs_infop->nostr);
 615         }
 616         rcu_read_lock();
 617         seq_printf(m, ",proto=%s",
 618                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 619         rcu_read_unlock();
 620         if (version == 4) {
 621                 if (nfss->port != NFS_PORT)
 622                         seq_printf(m, ",port=%u", nfss->port);
 623         } else
 624                 if (nfss->port)
 625                         seq_printf(m, ",port=%u", nfss->port);
 626
 627         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 628         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 629         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 630
 631         if (version != 4)
 632                 nfs_show_mountd_options(m, nfss, showdefaults);
 633         else
 634                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 635
 636         if (nfss->options & NFS_OPTION_FSCACHE)
 637                 seq_printf(m, ",fsc");
 638
 639         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 640                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 641                         seq_printf(m, ",lookupcache=none");
 642                 else
 643                         seq_printf(m, ",lookupcache=pos");
 644         }
 645
 646         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 647         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 648
 649         if (!local_flock && !local_fcntl)
 650                 seq_printf(m, ",local_lock=none");
 651         else if (local_flock && local_fcntl)
 652                 seq_printf(m, ",local_lock=all");
 653         else if (local_flock)
 654                 seq_printf(m, ",local_lock=flock");
 655         else
 656                 seq_printf(m, ",local_lock=posix");
 657 }
 658
 659 /*
 660  * Describe the mount options on this VFS mountpoint
 661  */
 662 int nfs_show_options(struct seq_file *m, struct dentry *root)
 663 {
 664         struct nfs_server *nfss = NFS_SB(root->d_sb);
 665
 666         nfs_show_mount_options(m, nfss, 0);
 667
 668         rcu_read_lock();
 669         seq_printf(m, ",addr=%s",
 670                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 671                                                         RPC_DISPLAY_ADDR));
 672         rcu_read_unlock();
 673
 674         return 0;
 675 }
 676
 677 #ifdef CONFIG_NFS_V4
 678 #ifdef CONFIG_NFS_V4_1
 679 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 680 {
 681         if (nfs4_has_session(server->nfs_client))
 682                 seq_printf(m, ",sessions");
 683 }
 684 #else
 685 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 686 #endif
 687 #endif
 688
 689 #ifdef CONFIG_NFS_V4_1
 690 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 691 {
 692         seq_printf(m, ",pnfs=");
 693         if (server->pnfs_curr_ld)
 694                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 695         else
 696                 seq_printf(m, "not configured");
 697 }
 698
 699 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 700 {
 701         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 702                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 703                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 704                            "date='%llu,%u'",
 705                            impl_id->name, impl_id->domain,
 706                            impl_id->date.seconds, impl_id->date.nseconds);
 707         }
 708 }
 709 #else
 710 #ifdef CONFIG_NFS_V4
 711 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 712 {
 713 }
 714 #endif
 715 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 716 {
 717 }
 718 #endif
 719
 720 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 721 {
 722         char *page = (char *) __get_free_page(GFP_KERNEL);
 723         char *devname, *dummy;
 724         int err = 0;
 725         if (!page)
 726                 return -ENOMEM;
 727         devname = nfs_path(&dummy, root, page, PAGE_SIZE);
 728         if (IS_ERR(devname))
 729                 err = PTR_ERR(devname);
 730         else
 731                 seq_escape(m, devname, " \t\n\\");
 732         free_page((unsigned long)page);
 733         return err;
 734 }
 735
 736 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 737 {
 738         seq_puts(m, "/");
 739         return 0;
 740 }
 741
 742 /*
 743  * Present statistical information for this VFS mountpoint
 744  */
 745 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 746 {
 747         int i, cpu;
 748         struct nfs_server *nfss = NFS_SB(root->d_sb);
 749         struct rpc_auth *auth = nfss->client->cl_auth;
 750         struct nfs_iostats totals = { };
 751
 752         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 753
 754         /*
 755          * Display all mount option settings
 756          */
 757         seq_printf(m, "\n\topts:\t");
 758         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 759         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 760         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 761         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 762         nfs_show_mount_options(m, nfss, 1);
 763
 764         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 765
 766         show_implementation_id(m, nfss);
 767
 768         seq_printf(m, "\n\tcaps:\t");
 769         seq_printf(m, "caps=0x%x", nfss->caps);
 770         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 771         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 772         seq_printf(m, ",bsize=%u", nfss->bsize);
 773         seq_printf(m, ",namlen=%u", nfss->namelen);
 774
 775 #ifdef CONFIG_NFS_V4
 776         if (nfss->nfs_client->rpc_ops->version == 4) {
 777                 seq_printf(m, "\n\tnfsv4:\t");
 778                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 779                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 780                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 781                 show_sessions(m, nfss);
 782                 show_pnfs(m, nfss);
 783         }
 784 #endif
 785
 786         /*
 787          * Display security flavor in effect for this mount
 788          */
 789         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 790         if (auth->au_flavor)
 791                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 792
 793         /*
 794          * Display superblock I/O counters
 795          */
 796         for_each_possible_cpu(cpu) {
 797                 struct nfs_iostats *stats;
 798
 799                 preempt_disable();
 800                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 801
 802                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 803                         totals.events[i] += stats->events[i];
 804                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 805                         totals.bytes[i] += stats->bytes[i];
 806 #ifdef CONFIG_NFS_FSCACHE
 807                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 808                         totals.fscache[i] += stats->fscache[i];
 809 #endif
 810
 811                 preempt_enable();
 812         }
 813
 814         seq_printf(m, "\n\tevents:\t");
 815         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 816                 seq_printf(m, "%lu ", totals.events[i]);
 817         seq_printf(m, "\n\tbytes:\t");
 818         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 819                 seq_printf(m, "%Lu ", totals.bytes[i]);
 820 #ifdef CONFIG_NFS_FSCACHE
 821         if (nfss->options & NFS_OPTION_FSCACHE) {
 822                 seq_printf(m, "\n\tfsc:\t");
 823                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 824                         seq_printf(m, "%Lu ", totals.bytes[i]);
 825         }
 826 #endif
 827         seq_printf(m, "\n");
 828
 829         rpc_print_iostats(m, nfss->client);
 830
 831         return 0;
 832 }
 833
 834 /*
 835  * Begin unmount by attempting to remove all automounted mountpoints we added
 836  * in response to xdev traversals and referrals
 837  */
 838 void nfs_umount_begin(struct super_block *sb)
 839 {
 840         struct nfs_server *server;
 841         struct rpc_clnt *rpc;
 842
 843         server = NFS_SB(sb);
 844         /* -EIO all pending I/O */
 845         rpc = server->client_acl;
 846         if (!IS_ERR(rpc))
 847                 rpc_killall_tasks(rpc);
 848         rpc = server->client;
 849         if (!IS_ERR(rpc))
 850                 rpc_killall_tasks(rpc);
 851 }
 852
 853 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 854 {
 855         struct nfs_parsed_mount_data *data;
 856
 857         data = kzalloc(sizeof(*data), GFP_KERNEL);
 858         if (data) {
 859                 data->acregmin          = NFS_DEF_ACREGMIN;
 860                 data->acregmax          = NFS_DEF_ACREGMAX;
 861                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 862                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 863                 data->mount_server.port = NFS_UNSPEC_PORT;
 864                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 865                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 866                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 867                 data->auth_flavor_len   = 1;
 868                 data->minorversion      = 0;
 869                 data->need_mount        = true;
 870                 data->net               = current->nsproxy->net_ns;
 871                 security_init_mnt_opts(&data->lsm_opts);
 872         }
 873         return data;
 874 }
 875
 876 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 877 {
 878         if (data) {
 879                 kfree(data->client_address);
 880                 kfree(data->mount_server.hostname);
 881                 kfree(data->nfs_server.export_path);
 882                 kfree(data->nfs_server.hostname);
 883                 kfree(data->fscache_uniq);
 884                 security_free_mnt_opts(&data->lsm_opts);
 885                 kfree(data);
 886         }
 887 }
 888
 889 /*
 890  * Sanity-check a server address provided by the mount command.
 891  *
 892  * Address family must be initialized, and address must not be
 893  * the ANY address for that family.
 894  */
 895 static int nfs_verify_server_address(struct sockaddr *addr)
 896 {
 897         switch (addr->sa_family) {
 898         case AF_INET: {
 899                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 900                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 901         }
 902         case AF_INET6: {
 903                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 904                 return !ipv6_addr_any(sa);
 905         }
 906         }
 907
 908         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 909         return 0;
 910 }
 911
 912 /*
 913  * Select between a default port value and a user-specified port value.
 914  * If a zero value is set, then autobind will be used.
 915  */
 916 static void nfs_set_port(struct sockaddr *sap, int *port,
 917                                  const unsigned short default_port)
 918 {
 919         if (*port == NFS_UNSPEC_PORT)
 920                 *port = default_port;
 921
 922         rpc_set_port(sap, *port);
 923 }
 924
 925 /*
 926  * Sanity check the NFS transport protocol.
 927  *
 928  */
 929 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 930 {
 931         switch (mnt->nfs_server.protocol) {
 932         case XPRT_TRANSPORT_UDP:
 933         case XPRT_TRANSPORT_TCP:
 934         case XPRT_TRANSPORT_RDMA:
 935                 break;
 936         default:
 937                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 938         }
 939 }
 940
 941 /*
 942  * For text based NFSv2/v3 mounts, the mount protocol transport default
 943  * settings should depend upon the specified NFS transport.
 944  */
 945 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 946 {
 947         nfs_validate_transport_protocol(mnt);
 948
 949         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 950             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 951                         return;
 952         switch (mnt->nfs_server.protocol) {
 953         case XPRT_TRANSPORT_UDP:
 954                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 955                 break;
 956         case XPRT_TRANSPORT_TCP:
 957         case XPRT_TRANSPORT_RDMA:
 958                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 959         }
 960 }
 961
 962 /*
 963  * Parse the value of the 'sec=' option.
 964  */
 965 static int nfs_parse_security_flavors(char *value,
 966                                       struct nfs_parsed_mount_data *mnt)
 967 {
 968         substring_t args[MAX_OPT_ARGS];
 969
 970         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 971
 972         switch (match_token(value, nfs_secflavor_tokens, args)) {
 973         case Opt_sec_none:
 974                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 975                 break;
 976         case Opt_sec_sys:
 977                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 978                 break;
 979         case Opt_sec_krb5:
 980                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 981                 break;
 982         case Opt_sec_krb5i:
 983                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 984                 break;
 985         case Opt_sec_krb5p:
 986                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 987                 break;
 988         case Opt_sec_lkey:
 989                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 990                 break;
 991         case Opt_sec_lkeyi:
 992                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 993                 break;
 994         case Opt_sec_lkeyp:
 995                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 996                 break;
 997         case Opt_sec_spkm:
 998                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
 999                 break;
1000         case Opt_sec_spkmi:
1001                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1002                 break;
1003         case Opt_sec_spkmp:
1004                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1005                 break;
1006         default:
1007                 return 0;
1008         }
1009
1010         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1011         mnt->auth_flavor_len = 1;
1012         return 1;
1013 }
1014
1015 static int nfs_parse_version_string(char *string,
1016                 struct nfs_parsed_mount_data *mnt,
1017                 substring_t *args)
1018 {
1019         mnt->flags &= ~NFS_MOUNT_VER3;
1020         switch (match_token(string, nfs_vers_tokens, args)) {
1021         case Opt_vers_2:
1022                 mnt->version = 2;
1023                 break;
1024         case Opt_vers_3:
1025                 mnt->flags |= NFS_MOUNT_VER3;
1026                 mnt->version = 3;
1027                 break;
1028         case Opt_vers_4:
1029                 /* Backward compatibility option. In future,
1030                  * the mount program should always supply
1031                  * a NFSv4 minor version number.
1032                  */
1033                 mnt->version = 4;
1034                 break;
1035         case Opt_vers_4_0:
1036                 mnt->version = 4;
1037                 mnt->minorversion = 0;
1038                 break;
1039         case Opt_vers_4_1:
1040                 mnt->version = 4;
1041                 mnt->minorversion = 1;
1042                 break;
1043         default:
1044                 return 0;
1045         }
1046         return 1;
1047 }
1048
1049 static int nfs_get_option_str(substring_t args[], char **option)
1050 {
1051         kfree(*option);
1052         *option = match_strdup(args);
1053         return !option;
1054 }
1055
1056 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1057 {
1058         int rc;
1059         char *string;
1060
1061         string = match_strdup(args);
1062         if (string == NULL)
1063                 return -ENOMEM;
1064         rc = strict_strtoul(string, 10, option);
1065         kfree(string);
1066
1067         return rc;
1068 }
1069
1070 /*
1071  * Error-check and convert a string of mount options from user space into
1072  * a data structure.  The whole mount string is processed; bad options are
1073  * skipped as they are encountered.  If there were no errors, return 1;
1074  * otherwise return 0 (zero).
1075  */
1076 static int nfs_parse_mount_options(char *raw,
1077                                    struct nfs_parsed_mount_data *mnt)
1078 {
1079         char *p, *string, *secdata;
1080         int rc, sloppy = 0, invalid_option = 0;
1081         unsigned short protofamily = AF_UNSPEC;
1082         unsigned short mountfamily = AF_UNSPEC;
1083
1084         if (!raw) {
1085                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1086                 return 1;
1087         }
1088         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1089
1090         secdata = alloc_secdata();
1091         if (!secdata)
1092                 goto out_nomem;
1093
1094         rc = security_sb_copy_data(raw, secdata);
1095         if (rc)
1096                 goto out_security_failure;
1097
1098         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1099         if (rc)
1100                 goto out_security_failure;
1101
1102         free_secdata(secdata);
1103
1104         while ((p = strsep(&raw, ",")) != NULL) {
1105                 substring_t args[MAX_OPT_ARGS];
1106                 unsigned long option;
1107                 int token;
1108
1109                 if (!*p)
1110                         continue;
1111
1112                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1113
1114                 token = match_token(p, nfs_mount_option_tokens, args);
1115                 switch (token) {
1116
1117                 /*
1118                  * boolean options:  foo/nofoo
1119                  */
1120                 case Opt_soft:
1121                         mnt->flags |= NFS_MOUNT_SOFT;
1122                         break;
1123                 case Opt_hard:
1124                         mnt->flags &= ~NFS_MOUNT_SOFT;
1125                         break;
1126                 case Opt_posix:
1127                         mnt->flags |= NFS_MOUNT_POSIX;
1128                         break;
1129                 case Opt_noposix:
1130                         mnt->flags &= ~NFS_MOUNT_POSIX;
1131                         break;
1132                 case Opt_cto:
1133                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1134                         break;
1135                 case Opt_nocto:
1136                         mnt->flags |= NFS_MOUNT_NOCTO;
1137                         break;
1138                 case Opt_ac:
1139                         mnt->flags &= ~NFS_MOUNT_NOAC;
1140                         break;
1141                 case Opt_noac:
1142                         mnt->flags |= NFS_MOUNT_NOAC;
1143                         break;
1144                 case Opt_lock:
1145                         mnt->flags &= ~NFS_MOUNT_NONLM;
1146                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1147                                         NFS_MOUNT_LOCAL_FCNTL);
1148                         break;
1149                 case Opt_nolock:
1150                         mnt->flags |= NFS_MOUNT_NONLM;
1151                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1152                                        NFS_MOUNT_LOCAL_FCNTL);
1153                         break;
1154                 case Opt_udp:
1155                         mnt->flags &= ~NFS_MOUNT_TCP;
1156                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1157                         break;
1158                 case Opt_tcp:
1159                         mnt->flags |= NFS_MOUNT_TCP;
1160                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1161                         break;
1162                 case Opt_rdma:
1163                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1164                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1165                         xprt_load_transport(p);
1166                         break;
1167                 case Opt_acl:
1168                         mnt->flags &= ~NFS_MOUNT_NOACL;
1169                         break;
1170                 case Opt_noacl:
1171                         mnt->flags |= NFS_MOUNT_NOACL;
1172                         break;
1173                 case Opt_rdirplus:
1174                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1175                         break;
1176                 case Opt_nordirplus:
1177                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1178                         break;
1179                 case Opt_sharecache:
1180                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1181                         break;
1182                 case Opt_nosharecache:
1183                         mnt->flags |= NFS_MOUNT_UNSHARED;
1184                         break;
1185                 case Opt_resvport:
1186                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1187                         break;
1188                 case Opt_noresvport:
1189                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1190                         break;
1191                 case Opt_fscache:
1192                         mnt->options |= NFS_OPTION_FSCACHE;
1193                         kfree(mnt->fscache_uniq);
1194                         mnt->fscache_uniq = NULL;
1195                         break;
1196                 case Opt_nofscache:
1197                         mnt->options &= ~NFS_OPTION_FSCACHE;
1198                         kfree(mnt->fscache_uniq);
1199                         mnt->fscache_uniq = NULL;
1200                         break;
1201
1202                 /*
1203                  * options that take numeric values
1204                  */
1205                 case Opt_port:
1206                         if (nfs_get_option_ul(args, &option) ||
1207                             option > USHRT_MAX)
1208                                 goto out_invalid_value;
1209                         mnt->nfs_server.port = option;
1210                         break;
1211                 case Opt_rsize:
1212                         if (nfs_get_option_ul(args, &option))
1213                                 goto out_invalid_value;
1214                         mnt->rsize = option;
1215                         break;
1216                 case Opt_wsize:
1217                         if (nfs_get_option_ul(args, &option))
1218                                 goto out_invalid_value;
1219                         mnt->wsize = option;
1220                         break;
1221                 case Opt_bsize:
1222                         if (nfs_get_option_ul(args, &option))
1223                                 goto out_invalid_value;
1224                         mnt->bsize = option;
1225                         break;
1226                 case Opt_timeo:
1227                         if (nfs_get_option_ul(args, &option) || option == 0)
1228                                 goto out_invalid_value;
1229                         mnt->timeo = option;
1230                         break;
1231                 case Opt_retrans:
1232                         if (nfs_get_option_ul(args, &option) || option == 0)
1233                                 goto out_invalid_value;
1234                         mnt->retrans = option;
1235                         break;
1236                 case Opt_acregmin:
1237                         if (nfs_get_option_ul(args, &option))
1238                                 goto out_invalid_value;
1239                         mnt->acregmin = option;
1240                         break;
1241                 case Opt_acregmax:
1242                         if (nfs_get_option_ul(args, &option))
1243                                 goto out_invalid_value;
1244                         mnt->acregmax = option;
1245                         break;
1246                 case Opt_acdirmin:
1247                         if (nfs_get_option_ul(args, &option))
1248                                 goto out_invalid_value;
1249                         mnt->acdirmin = option;
1250                         break;
1251                 case Opt_acdirmax:
1252                         if (nfs_get_option_ul(args, &option))
1253                                 goto out_invalid_value;
1254                         mnt->acdirmax = option;
1255                         break;
1256                 case Opt_actimeo:
1257                         if (nfs_get_option_ul(args, &option))
1258                                 goto out_invalid_value;
1259                         mnt->acregmin = mnt->acregmax =
1260                         mnt->acdirmin = mnt->acdirmax = option;
1261                         break;
1262                 case Opt_namelen:
1263                         if (nfs_get_option_ul(args, &option))
1264                                 goto out_invalid_value;
1265                         mnt->namlen = option;
1266                         break;
1267                 case Opt_mountport:
1268                         if (nfs_get_option_ul(args, &option) ||
1269                             option > USHRT_MAX)
1270                                 goto out_invalid_value;
1271                         mnt->mount_server.port = option;
1272                         break;
1273                 case Opt_mountvers:
1274                         if (nfs_get_option_ul(args, &option) ||
1275                             option < NFS_MNT_VERSION ||
1276                             option > NFS_MNT3_VERSION)
1277                                 goto out_invalid_value;
1278                         mnt->mount_server.version = option;
1279                         break;
1280                 case Opt_minorversion:
1281                         if (nfs_get_option_ul(args, &option))
1282                                 goto out_invalid_value;
1283                         if (option > NFS4_MAX_MINOR_VERSION)
1284                                 goto out_invalid_value;
1285                         mnt->minorversion = option;
1286                         break;
1287
1288                 /*
1289                  * options that take text values
1290                  */
1291                 case Opt_nfsvers:
1292                         string = match_strdup(args);
1293                         if (string == NULL)
1294                                 goto out_nomem;
1295                         rc = nfs_parse_version_string(string, mnt, args);
1296                         kfree(string);
1297                         if (!rc)
1298                                 goto out_invalid_value;
1299                         break;
1300                 case Opt_sec:
1301                         string = match_strdup(args);
1302                         if (string == NULL)
1303                                 goto out_nomem;
1304                         rc = nfs_parse_security_flavors(string, mnt);
1305                         kfree(string);
1306                         if (!rc) {
1307                                 dfprintk(MOUNT, "NFS:   unrecognized "
1308                                                 "security flavor\n");
1309                                 return 0;
1310                         }
1311                         break;
1312                 case Opt_proto:
1313                         string = match_strdup(args);
1314                         if (string == NULL)
1315                                 goto out_nomem;
1316                         token = match_token(string,
1317                                             nfs_xprt_protocol_tokens, args);
1318
1319                         protofamily = AF_INET;
1320                         switch (token) {
1321                         case Opt_xprt_udp6:
1322                                 protofamily = AF_INET6;
1323                         case Opt_xprt_udp:
1324                                 mnt->flags &= ~NFS_MOUNT_TCP;
1325                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1326                                 break;
1327                         case Opt_xprt_tcp6:
1328                                 protofamily = AF_INET6;
1329                         case Opt_xprt_tcp:
1330                                 mnt->flags |= NFS_MOUNT_TCP;
1331                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1332                                 break;
1333                         case Opt_xprt_rdma:
1334                                 /* vector side protocols to TCP */
1335                                 mnt->flags |= NFS_MOUNT_TCP;
1336                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1337                                 xprt_load_transport(string);
1338                                 break;
1339                         default:
1340                                 dfprintk(MOUNT, "NFS:   unrecognized "
1341                                                 "transport protocol\n");
1342                                 kfree(string);
1343                                 return 0;
1344                         }
1345                         kfree(string);
1346                         break;
1347                 case Opt_mountproto:
1348                         string = match_strdup(args);
1349                         if (string == NULL)
1350                                 goto out_nomem;
1351                         token = match_token(string,
1352                                             nfs_xprt_protocol_tokens, args);
1353                         kfree(string);
1354
1355                         mountfamily = AF_INET;
1356                         switch (token) {
1357                         case Opt_xprt_udp6:
1358                                 mountfamily = AF_INET6;
1359                         case Opt_xprt_udp:
1360                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1361                                 break;
1362                         case Opt_xprt_tcp6:
1363                                 mountfamily = AF_INET6;
1364                         case Opt_xprt_tcp:
1365                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1366                                 break;
1367                         case Opt_xprt_rdma: /* not used for side protocols */
1368                         default:
1369                                 dfprintk(MOUNT, "NFS:   unrecognized "
1370                                                 "transport protocol\n");
1371                                 return 0;
1372                         }
1373                         break;
1374                 case Opt_addr:
1375                         string = match_strdup(args);
1376                         if (string == NULL)
1377                                 goto out_nomem;
1378                         mnt->nfs_server.addrlen =
1379                                 rpc_pton(mnt->net, string, strlen(string),
1380                                         (struct sockaddr *)
1381                                         &mnt->nfs_server.address,
1382                                         sizeof(mnt->nfs_server.address));
1383                         kfree(string);
1384                         if (mnt->nfs_server.addrlen == 0)
1385                                 goto out_invalid_address;
1386                         break;
1387                 case Opt_clientaddr:
1388                         if (nfs_get_option_str(args, &mnt->client_address))
1389                                 goto out_nomem;
1390                         break;
1391                 case Opt_mounthost:
1392                         if (nfs_get_option_str(args,
1393                                                &mnt->mount_server.hostname))
1394                                 goto out_nomem;
1395                         break;
1396                 case Opt_mountaddr:
1397                         string = match_strdup(args);
1398                         if (string == NULL)
1399                                 goto out_nomem;
1400                         mnt->mount_server.addrlen =
1401                                 rpc_pton(mnt->net, string, strlen(string),
1402                                         (struct sockaddr *)
1403                                         &mnt->mount_server.address,
1404                                         sizeof(mnt->mount_server.address));
1405                         kfree(string);
1406                         if (mnt->mount_server.addrlen == 0)
1407                                 goto out_invalid_address;
1408                         break;
1409                 case Opt_lookupcache:
1410                         string = match_strdup(args);
1411                         if (string == NULL)
1412                                 goto out_nomem;
1413                         token = match_token(string,
1414                                         nfs_lookupcache_tokens, args);
1415                         kfree(string);
1416                         switch (token) {
1417                                 case Opt_lookupcache_all:
1418                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1419                                         break;
1420                                 case Opt_lookupcache_positive:
1421                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1422                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1423                                         break;
1424                                 case Opt_lookupcache_none:
1425                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1426                                         break;
1427                                 default:
1428                                         dfprintk(MOUNT, "NFS:   invalid "
1429                                                         "lookupcache argument\n");
1430                                         return 0;
1431                         };
1432                         break;
1433                 case Opt_fscache_uniq:
1434                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1435                                 goto out_nomem;
1436                         mnt->options |= NFS_OPTION_FSCACHE;
1437                         break;
1438                 case Opt_local_lock:
1439                         string = match_strdup(args);
1440                         if (string == NULL)
1441                                 goto out_nomem;
1442                         token = match_token(string, nfs_local_lock_tokens,
1443                                         args);
1444                         kfree(string);
1445                         switch (token) {
1446                         case Opt_local_lock_all:
1447                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1448                                                NFS_MOUNT_LOCAL_FCNTL);
1449                                 break;
1450                         case Opt_local_lock_flock:
1451                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1452                                 break;
1453                         case Opt_local_lock_posix:
1454                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1455                                 break;
1456                         case Opt_local_lock_none:
1457                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1458                                                 NFS_MOUNT_LOCAL_FCNTL);
1459                                 break;
1460                         default:
1461                                 dfprintk(MOUNT, "NFS:   invalid "
1462                                                 "local_lock argument\n");
1463                                 return 0;
1464                         };
1465                         break;
1466
1467                 /*
1468                  * Special options
1469                  */
1470                 case Opt_sloppy:
1471                         sloppy = 1;
1472                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1473                         break;
1474                 case Opt_userspace:
1475                 case Opt_deprecated:
1476                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1477                                         "'%s'\n", p);
1478                         break;
1479
1480                 default:
1481                         invalid_option = 1;
1482                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1483                                         "'%s'\n", p);
1484                 }
1485         }
1486
1487         if (!sloppy && invalid_option)
1488                 return 0;
1489
1490         if (mnt->minorversion && mnt->version != 4)
1491                 goto out_minorversion_mismatch;
1492
1493         /*
1494          * verify that any proto=/mountproto= options match the address
1495          * familiies in the addr=/mountaddr= options.
1496          */
1497         if (protofamily != AF_UNSPEC &&
1498             protofamily != mnt->nfs_server.address.ss_family)
1499                 goto out_proto_mismatch;
1500
1501         if (mountfamily != AF_UNSPEC) {
1502                 if (mnt->mount_server.addrlen) {
1503                         if (mountfamily != mnt->mount_server.address.ss_family)
1504                                 goto out_mountproto_mismatch;
1505                 } else {
1506                         if (mountfamily != mnt->nfs_server.address.ss_family)
1507                                 goto out_mountproto_mismatch;
1508                 }
1509         }
1510
1511         return 1;
1512
1513 out_mountproto_mismatch:
1514         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1515                          "option\n");
1516         return 0;
1517 out_proto_mismatch:
1518         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1519         return 0;
1520 out_invalid_address:
1521         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1522         return 0;
1523 out_invalid_value:
1524         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1525         return 0;
1526 out_minorversion_mismatch:
1527         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1528                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1529         return 0;
1530 out_nomem:
1531         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1532         return 0;
1533 out_security_failure:
1534         free_secdata(secdata);
1535         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1536         return 0;
1537 }
1538
1539 /*
1540  * Match the requested auth flavors with the list returned by
1541  * the server.  Returns zero and sets the mount's authentication
1542  * flavor on success; returns -EACCES if server does not support
1543  * the requested flavor.
1544  */
1545 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1546                              struct nfs_mount_request *request)
1547 {
1548         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1549
1550         /*
1551          * Certain releases of Linux's mountd return an empty
1552          * flavor list.  To prevent behavioral regression with
1553          * these servers (ie. rejecting mounts that used to
1554          * succeed), revert to pre-2.6.32 behavior (no checking)
1555          * if the returned flavor list is empty.
1556          */
1557         if (server_authlist_len == 0)
1558                 return 0;
1559
1560         /*
1561          * We avoid sophisticated negotiating here, as there are
1562          * plenty of cases where we can get it wrong, providing
1563          * either too little or too much security.
1564          *
1565          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1566          * flavor listed first.  However, some servers list
1567          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1568          * preferred default, in args->auth_flavors[0] if user
1569          * didn't specify sec= mount option.
1570          */
1571         for (i = 0; i < args->auth_flavor_len; i++)
1572                 for (j = 0; j < server_authlist_len; j++)
1573                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1574                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1575                                         request->auth_flavs[j]);
1576                                 args->auth_flavors[0] = request->auth_flavs[j];
1577                                 return 0;
1578                         }
1579
1580         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1581         nfs_umount(request);
1582         return -EACCES;
1583 }
1584
1585 /*
1586  * Use the remote server's MOUNT service to request the NFS file handle
1587  * corresponding to the provided path.
1588  */
1589 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1590                              struct nfs_fh *root_fh)
1591 {
1592         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1593         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1594         struct nfs_mount_request request = {
1595                 .sap            = (struct sockaddr *)
1596                                                 &args->mount_server.address,
1597                 .dirpath        = args->nfs_server.export_path,
1598                 .protocol       = args->mount_server.protocol,
1599                 .fh             = root_fh,
1600                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1601                 .auth_flav_len  = &server_authlist_len,
1602                 .auth_flavs     = server_authlist,
1603                 .net            = args->net,
1604         };
1605         int status;
1606
1607         if (args->mount_server.version == 0) {
1608                 switch (args->version) {
1609                         default:
1610                                 args->mount_server.version = NFS_MNT3_VERSION;
1611                                 break;
1612                         case 2:
1613                                 args->mount_server.version = NFS_MNT_VERSION;
1614                 }
1615         }
1616         request.version = args->mount_server.version;
1617
1618         if (args->mount_server.hostname)
1619                 request.hostname = args->mount_server.hostname;
1620         else
1621                 request.hostname = args->nfs_server.hostname;
1622
1623         /*
1624          * Construct the mount server's address.
1625          */
1626         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1627                 memcpy(request.sap, &args->nfs_server.address,
1628                        args->nfs_server.addrlen);
1629                 args->mount_server.addrlen = args->nfs_server.addrlen;
1630         }
1631         request.salen = args->mount_server.addrlen;
1632         nfs_set_port(request.sap, &args->mount_server.port, 0);
1633
1634         /*
1635          * Now ask the mount server to map our export path
1636          * to a file handle.
1637          */
1638         status = nfs_mount(&request);
1639         if (status != 0) {
1640                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1641                                 request.hostname, status);
1642                 return status;
1643         }
1644
1645         /*
1646          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1647          */
1648         if (args->mount_server.version != NFS_MNT3_VERSION)
1649                 return 0;
1650         return nfs_walk_authlist(args, &request);
1651 }
1652
1653 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1654                              struct nfs_mount_info *mount_info,
1655                              struct nfs_subversion *nfs_mod)
1656 {
1657         int status;
1658         struct nfs_server *server;
1659
1660         if (mount_info->parsed->need_mount) {
1661                 status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1662                 if (status)
1663                         return ERR_PTR(status);
1664         }
1665
1666         /* Get a volume representation */
1667         server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1668         if (IS_ERR(server))
1669                 return ERR_CAST(server);
1670
1671         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
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 nfs23_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         args->version = NFS_DEFAULT_VERSION;
1774         switch (data->version) {
1775         case 1:
1776                 data->namlen = 0;
1777         case 2:
1778                 data->bsize = 0;
1779         case 3:
1780                 if (data->flags & NFS_MOUNT_VER3)
1781                         goto out_no_v3;
1782                 data->root.size = NFS2_FHSIZE;
1783                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1784         case 4:
1785                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1786                         goto out_no_sec;
1787         case 5:
1788                 memset(data->context, 0, sizeof(data->context));
1789         case 6:
1790                 if (data->flags & NFS_MOUNT_VER3) {
1791                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1792                                 goto out_invalid_fh;
1793                         mntfh->size = data->root.size;
1794                         args->version = 3;
1795                 } else {
1796                         mntfh->size = NFS2_FHSIZE;
1797                         args->version = 2;
1798                 }
1799
1800
1801                 memcpy(mntfh->data, data->root.data, mntfh->size);
1802                 if (mntfh->size < sizeof(mntfh->data))
1803                         memset(mntfh->data + mntfh->size, 0,
1804                                sizeof(mntfh->data) - mntfh->size);
1805
1806                 /*
1807                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1808                  * can deal with.
1809                  */
1810                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1811                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1812                 args->rsize             = data->rsize;
1813                 args->wsize             = data->wsize;
1814                 args->timeo             = data->timeo;
1815                 args->retrans           = data->retrans;
1816                 args->acregmin          = data->acregmin;
1817                 args->acregmax          = data->acregmax;
1818                 args->acdirmin          = data->acdirmin;
1819                 args->acdirmax          = data->acdirmax;
1820                 args->need_mount        = false;
1821
1822                 memcpy(sap, &data->addr, sizeof(data->addr));
1823                 args->nfs_server.addrlen = sizeof(data->addr);
1824                 if (!nfs_verify_server_address(sap))
1825                         goto out_no_address;
1826
1827                 if (!(data->flags & NFS_MOUNT_TCP))
1828                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1829                 /* N.B. caller will free nfs_server.hostname in all cases */
1830                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1831                 args->namlen            = data->namlen;
1832                 args->bsize             = data->bsize;
1833
1834                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1835                         args->auth_flavors[0] = data->pseudoflavor;
1836                 if (!args->nfs_server.hostname)
1837                         goto out_nomem;
1838
1839                 if (!(data->flags & NFS_MOUNT_NONLM))
1840                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1841                                          NFS_MOUNT_LOCAL_FCNTL);
1842                 else
1843                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1844                                         NFS_MOUNT_LOCAL_FCNTL);
1845                 /*
1846                  * The legacy version 6 binary mount data from userspace has a
1847                  * field used only to transport selinux information into the
1848                  * the kernel.  To continue to support that functionality we
1849                  * have a touch of selinux knowledge here in the NFS code. The
1850                  * userspace code converted context=blah to just blah so we are
1851                  * converting back to the full string selinux understands.
1852                  */
1853                 if (data->context[0]){
1854 #ifdef CONFIG_SECURITY_SELINUX
1855                         int rc;
1856                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1857                         if (!opts_str)
1858                                 return -ENOMEM;
1859                         strcpy(opts_str, "context=");
1860                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1861                         strcat(opts_str, &data->context[0]);
1862                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1863                         kfree(opts_str);
1864                         if (rc)
1865                                 return rc;
1866 #else
1867                         return -EINVAL;
1868 #endif
1869                 }
1870
1871                 break;
1872         default:
1873                 return NFS_TEXT_DATA;
1874         }
1875
1876 #ifndef CONFIG_NFS_V3
1877         if (args->version == 3)
1878                 goto out_v3_not_compiled;
1879 #endif /* !CONFIG_NFS_V3 */
1880
1881         return 0;
1882
1883 out_no_data:
1884         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1885         return -EINVAL;
1886
1887 out_no_v3:
1888         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1889                  data->version);
1890         return -EINVAL;
1891
1892 out_no_sec:
1893         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1894         return -EINVAL;
1895
1896 #ifndef CONFIG_NFS_V3
1897 out_v3_not_compiled:
1898         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1899         return -EPROTONOSUPPORT;
1900 #endif /* !CONFIG_NFS_V3 */
1901
1902 out_nomem:
1903         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1904         return -ENOMEM;
1905
1906 out_no_address:
1907         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1908         return -EINVAL;
1909
1910 out_invalid_fh:
1911         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1912         return -EINVAL;
1913 }
1914
1915 #ifdef CONFIG_NFS_V4
1916 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1917                                    void *options,
1918                                    struct nfs_parsed_mount_data *args,
1919                                    struct nfs_fh *mntfh,
1920                                    const char *dev_name)
1921 {
1922         if (fs_type == &nfs_fs_type)
1923                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1924         return nfs4_validate_mount_data(options, args, dev_name);
1925 }
1926 #else
1927 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1928                                    void *options,
1929                                    struct nfs_parsed_mount_data *args,
1930                                    struct nfs_fh *mntfh,
1931                                    const char *dev_name)
1932 {
1933         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1934 }
1935 #endif
1936
1937 static int nfs_validate_text_mount_data(void *options,
1938                                         struct nfs_parsed_mount_data *args,
1939                                         const char *dev_name)
1940 {
1941         int port = 0;
1942         int max_namelen = PAGE_SIZE;
1943         int max_pathlen = NFS_MAXPATHLEN;
1944         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1945
1946         if (nfs_parse_mount_options((char *)options, args) == 0)
1947                 return -EINVAL;
1948
1949         if (!nfs_verify_server_address(sap))
1950                 goto out_no_address;
1951
1952         if (args->version == 4) {
1953 #ifdef CONFIG_NFS_V4
1954                 port = NFS_PORT;
1955                 max_namelen = NFS4_MAXNAMLEN;
1956                 max_pathlen = NFS4_MAXPATHLEN;
1957                 nfs_validate_transport_protocol(args);
1958                 nfs4_validate_mount_flags(args);
1959 #else
1960                 goto out_v4_not_compiled;
1961 #endif /* CONFIG_NFS_V4 */
1962         } else
1963                 nfs_set_mount_transport_protocol(args);
1964
1965         nfs_set_port(sap, &args->nfs_server.port, port);
1966
1967         if (args->auth_flavor_len > 1)
1968                 goto out_bad_auth;
1969
1970         return nfs_parse_devname(dev_name,
1971                                    &args->nfs_server.hostname,
1972                                    max_namelen,
1973                                    &args->nfs_server.export_path,
1974                                    max_pathlen);
1975
1976 #ifndef CONFIG_NFS_V4
1977 out_v4_not_compiled:
1978         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1979         return -EPROTONOSUPPORT;
1980 #endif /* !CONFIG_NFS_V4 */
1981
1982 out_no_address:
1983         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1984         return -EINVAL;
1985
1986 out_bad_auth:
1987         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
1988         return -EINVAL;
1989 }
1990
1991 static int
1992 nfs_compare_remount_data(struct nfs_server *nfss,
1993                          struct nfs_parsed_mount_data *data)
1994 {
1995         if (data->flags != nfss->flags ||
1996             data->rsize != nfss->rsize ||
1997             data->wsize != nfss->wsize ||
1998             data->retrans != nfss->client->cl_timeout->to_retries ||
1999             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2000             data->acregmin != nfss->acregmin / HZ ||
2001             data->acregmax != nfss->acregmax / HZ ||
2002             data->acdirmin != nfss->acdirmin / HZ ||
2003             data->acdirmax != nfss->acdirmax / HZ ||
2004             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2005             data->nfs_server.port != nfss->port ||
2006             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2007             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2008                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2009                 return -EINVAL;
2010
2011         return 0;
2012 }
2013
2014 int
2015 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2016 {
2017         int error;
2018         struct nfs_server *nfss = sb->s_fs_info;
2019         struct nfs_parsed_mount_data *data;
2020         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2021         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2022         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2023
2024         /*
2025          * Userspace mount programs that send binary options generally send
2026          * them populated with default values. We have no way to know which
2027          * ones were explicitly specified. Fall back to legacy behavior and
2028          * just return success.
2029          */
2030         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2031             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2032                                            options->version <= 6))))
2033                 return 0;
2034
2035         data = kzalloc(sizeof(*data), GFP_KERNEL);
2036         if (data == NULL)
2037                 return -ENOMEM;
2038
2039         /* fill out struct with values from existing mount */
2040         data->flags = nfss->flags;
2041         data->rsize = nfss->rsize;
2042         data->wsize = nfss->wsize;
2043         data->retrans = nfss->client->cl_timeout->to_retries;
2044         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2045         data->acregmin = nfss->acregmin / HZ;
2046         data->acregmax = nfss->acregmax / HZ;
2047         data->acdirmin = nfss->acdirmin / HZ;
2048         data->acdirmax = nfss->acdirmax / HZ;
2049         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2050         data->nfs_server.port = nfss->port;
2051         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2052         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2053                 data->nfs_server.addrlen);
2054
2055         /* overwrite those values with any that were specified */
2056         error = nfs_parse_mount_options((char *)options, data);
2057         if (error < 0)
2058                 goto out;
2059
2060         /*
2061          * noac is a special case. It implies -o sync, but that's not
2062          * necessarily reflected in the mtab options. do_remount_sb
2063          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2064          * remount options, so we have to explicitly reset it.
2065          */
2066         if (data->flags & NFS_MOUNT_NOAC)
2067                 *flags |= MS_SYNCHRONOUS;
2068
2069         /* compare new mount options with old ones */
2070         error = nfs_compare_remount_data(nfss, data);
2071 out:
2072         kfree(data);
2073         return error;
2074 }
2075
2076 /*
2077  * Initialise the common bits of the superblock
2078  */
2079 inline void nfs_initialise_sb(struct super_block *sb)
2080 {
2081         struct nfs_server *server = NFS_SB(sb);
2082
2083         sb->s_magic = NFS_SUPER_MAGIC;
2084
2085         /* We probably want something more informative here */
2086         snprintf(sb->s_id, sizeof(sb->s_id),
2087                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2088
2089         if (sb->s_blocksize == 0)
2090                 sb->s_blocksize = nfs_block_bits(server->wsize,
2091                                                  &sb->s_blocksize_bits);
2092
2093         sb->s_bdi = &server->backing_dev_info;
2094
2095         nfs_super_set_maxbytes(sb, server->maxfilesize);
2096 }
2097
2098 /*
2099  * Finish setting up an NFS2/3 superblock
2100  */
2101 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2102 {
2103         struct nfs_parsed_mount_data *data = mount_info->parsed;
2104         struct nfs_server *server = NFS_SB(sb);
2105
2106         sb->s_blocksize_bits = 0;
2107         sb->s_blocksize = 0;
2108         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2109         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2110         if (data && data->bsize)
2111                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2112
2113         if (server->nfs_client->rpc_ops->version != 2) {
2114                 /* The VFS shouldn't apply the umask to mode bits. We will do
2115                  * so ourselves when necessary.
2116                  */
2117                 sb->s_flags |= MS_POSIXACL;
2118                 sb->s_time_gran = 1;
2119         }
2120
2121         nfs_initialise_sb(sb);
2122 }
2123
2124 /*
2125  * Finish setting up a cloned NFS2/3/4 superblock
2126  */
2127 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2128 {
2129         const struct super_block *old_sb = mount_info->cloned->sb;
2130         struct nfs_server *server = NFS_SB(sb);
2131
2132         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2133         sb->s_blocksize = old_sb->s_blocksize;
2134         sb->s_maxbytes = old_sb->s_maxbytes;
2135         sb->s_xattr = old_sb->s_xattr;
2136         sb->s_op = old_sb->s_op;
2137         sb->s_time_gran = 1;
2138
2139         if (server->nfs_client->rpc_ops->version != 2) {
2140                 /* The VFS shouldn't apply the umask to mode bits. We will do
2141                  * so ourselves when necessary.
2142                  */
2143                 sb->s_flags |= MS_POSIXACL;
2144         }
2145
2146         nfs_initialise_sb(sb);
2147 }
2148
2149 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2150 {
2151         const struct nfs_server *a = s->s_fs_info;
2152         const struct rpc_clnt *clnt_a = a->client;
2153         const struct rpc_clnt *clnt_b = b->client;
2154
2155         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2156                 goto Ebusy;
2157         if (a->nfs_client != b->nfs_client)
2158                 goto Ebusy;
2159         if (a->flags != b->flags)
2160                 goto Ebusy;
2161         if (a->wsize != b->wsize)
2162                 goto Ebusy;
2163         if (a->rsize != b->rsize)
2164                 goto Ebusy;
2165         if (a->acregmin != b->acregmin)
2166                 goto Ebusy;
2167         if (a->acregmax != b->acregmax)
2168                 goto Ebusy;
2169         if (a->acdirmin != b->acdirmin)
2170                 goto Ebusy;
2171         if (a->acdirmax != b->acdirmax)
2172                 goto Ebusy;
2173         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2174                 goto Ebusy;
2175         return 1;
2176 Ebusy:
2177         return 0;
2178 }
2179
2180 struct nfs_sb_mountdata {
2181         struct nfs_server *server;
2182         int mntflags;
2183 };
2184
2185 static int nfs_set_super(struct super_block *s, void *data)
2186 {
2187         struct nfs_sb_mountdata *sb_mntdata = data;
2188         struct nfs_server *server = sb_mntdata->server;
2189         int ret;
2190
2191         s->s_flags = sb_mntdata->mntflags;
2192         s->s_fs_info = server;
2193         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2194         ret = set_anon_super(s, server);
2195         if (ret == 0)
2196                 server->s_dev = s->s_dev;
2197         return ret;
2198 }
2199
2200 static int nfs_compare_super_address(struct nfs_server *server1,
2201                                      struct nfs_server *server2)
2202 {
2203         struct sockaddr *sap1, *sap2;
2204
2205         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2206         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2207
2208         if (sap1->sa_family != sap2->sa_family)
2209                 return 0;
2210
2211         switch (sap1->sa_family) {
2212         case AF_INET: {
2213                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2214                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2215                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2216                         return 0;
2217                 if (sin1->sin_port != sin2->sin_port)
2218                         return 0;
2219                 break;
2220         }
2221         case AF_INET6: {
2222                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2223                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2224                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2225                         return 0;
2226                 if (sin1->sin6_port != sin2->sin6_port)
2227                         return 0;
2228                 break;
2229         }
2230         default:
2231                 return 0;
2232         }
2233
2234         return 1;
2235 }
2236
2237 static int nfs_compare_super(struct super_block *sb, void *data)
2238 {
2239         struct nfs_sb_mountdata *sb_mntdata = data;
2240         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2241         int mntflags = sb_mntdata->mntflags;
2242
2243         if (!nfs_compare_super_address(old, server))
2244                 return 0;
2245         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2246         if (old->flags & NFS_MOUNT_UNSHARED)
2247                 return 0;
2248         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2249                 return 0;
2250         return nfs_compare_mount_options(sb, server, mntflags);
2251 }
2252
2253 #ifdef CONFIG_NFS_FSCACHE
2254 static void nfs_get_cache_cookie(struct super_block *sb,
2255                                  struct nfs_parsed_mount_data *parsed,
2256                                  struct nfs_clone_mount *cloned)
2257 {
2258         char *uniq = NULL;
2259         int ulen = 0;
2260
2261         if (parsed && parsed->fscache_uniq) {
2262                 uniq = parsed->fscache_uniq;
2263                 ulen = strlen(parsed->fscache_uniq);
2264         } else if (cloned) {
2265                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2266                 if (mnt_s->fscache_key) {
2267                         uniq = mnt_s->fscache_key->key.uniquifier;
2268                         ulen = mnt_s->fscache_key->key.uniq_len;
2269                 };
2270         }
2271
2272         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2273 }
2274 #else
2275 static void nfs_get_cache_cookie(struct super_block *sb,
2276                                  struct nfs_parsed_mount_data *parsed,
2277                                  struct nfs_clone_mount *cloned)
2278 {
2279 }
2280 #endif
2281
2282 static int nfs_bdi_register(struct nfs_server *server)
2283 {
2284         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2285 }
2286
2287 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2288                         struct nfs_mount_info *mount_info)
2289 {
2290         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2291 }
2292
2293 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2294                           struct nfs_mount_info *mount_info)
2295 {
2296         /* clone any lsm security options from the parent to the new sb */
2297         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2298         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2299                 return -ESTALE;
2300         return 0;
2301 }
2302
2303 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2304                                    int flags, const char *dev_name,
2305                                    struct nfs_mount_info *mount_info,
2306                                    struct nfs_subversion *nfs_mod)
2307 {
2308         struct super_block *s;
2309         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2310         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2311         struct nfs_sb_mountdata sb_mntdata = {
2312                 .mntflags = flags,
2313                 .server = server,
2314         };
2315         int error;
2316
2317         if (server->flags & NFS_MOUNT_UNSHARED)
2318                 compare_super = NULL;
2319
2320         /* -o noac implies -o sync */
2321         if (server->flags & NFS_MOUNT_NOAC)
2322                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2323
2324         /* Get a superblock - note that we may end up sharing one that already exists */
2325         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2326         if (IS_ERR(s)) {
2327                 mntroot = ERR_CAST(s);
2328                 goto out_err_nosb;
2329         }
2330
2331         if (s->s_fs_info != server) {
2332                 nfs_free_server(server);
2333                 server = NULL;
2334         } else {
2335                 error = nfs_bdi_register(server);
2336                 if (error) {
2337                         mntroot = ERR_PTR(error);
2338                         goto error_splat_bdi;
2339                 }
2340         }
2341
2342         if (!s->s_root) {
2343                 /* initial superblock/root creation */
2344                 mount_info->fill_super(s, mount_info);
2345                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2346         }
2347
2348         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2349         if (IS_ERR(mntroot))
2350                 goto error_splat_super;
2351
2352         error = mount_info->set_security(s, mntroot, mount_info);
2353         if (error)
2354                 goto error_splat_root;
2355
2356         s->s_flags |= MS_ACTIVE;
2357
2358 out:
2359         return mntroot;
2360
2361 out_err_nosb:
2362         nfs_free_server(server);
2363         goto out;
2364
2365 error_splat_root:
2366         dput(mntroot);
2367         mntroot = ERR_PTR(error);
2368 error_splat_super:
2369         if (server && !s->s_root)
2370                 bdi_unregister(&server->backing_dev_info);
2371 error_splat_bdi:
2372         deactivate_locked_super(s);
2373         goto out;
2374 }
2375
2376 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2377         int flags, const char *dev_name, void *raw_data)
2378 {
2379         struct nfs_mount_info mount_info = {
2380                 .fill_super = nfs_fill_super,
2381                 .set_security = nfs_set_sb_security,
2382         };
2383         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2384         struct nfs_subversion *nfs_mod;
2385         int error;
2386
2387         mount_info.parsed = nfs_alloc_parsed_mount_data();
2388         mount_info.mntfh = nfs_alloc_fhandle();
2389         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2390                 goto out;
2391
2392         /* Validate the mount data */
2393         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2394         if (error == NFS_TEXT_DATA)
2395                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2396         if (error < 0) {
2397                 mntroot = ERR_PTR(error);
2398                 goto out;
2399         }
2400
2401         nfs_mod = get_nfs_version(mount_info.parsed->version);
2402         if (IS_ERR(nfs_mod)) {
2403                 mntroot = ERR_CAST(nfs_mod);
2404                 goto out;
2405         }
2406
2407         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2408
2409         put_nfs_version(nfs_mod);
2410 out:
2411         nfs_free_parsed_mount_data(mount_info.parsed);
2412         nfs_free_fhandle(mount_info.mntfh);
2413         return mntroot;
2414 }
2415
2416 /*
2417  * Ensure that we unregister the bdi before kill_anon_super
2418  * releases the device name
2419  */
2420 void nfs_put_super(struct super_block *s)
2421 {
2422         struct nfs_server *server = NFS_SB(s);
2423
2424         bdi_unregister(&server->backing_dev_info);
2425 }
2426
2427 /*
2428  * Destroy an NFS2/3 superblock
2429  */
2430 void nfs_kill_super(struct super_block *s)
2431 {
2432         struct nfs_server *server = NFS_SB(s);
2433
2434         kill_anon_super(s);
2435         nfs_fscache_release_super_cookie(s);
2436         nfs_free_server(server);
2437 }
2438
2439 /*
2440  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2441  */
2442 struct dentry *
2443 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2444                 const char *dev_name, void *raw_data)
2445 {
2446         struct nfs_clone_mount *data = raw_data;
2447         struct nfs_mount_info mount_info = {
2448                 .fill_super = nfs_clone_super,
2449                 .set_security = nfs_clone_sb_security,
2450                 .cloned = data,
2451         };
2452         struct nfs_server *server;
2453         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2454         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2455         int error;
2456
2457         dprintk("--> nfs_xdev_mount_common()\n");
2458
2459         mount_info.mntfh = mount_info.cloned->fh;
2460
2461         /* create a new volume representation */
2462         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2463         if (IS_ERR(server)) {
2464                 error = PTR_ERR(server);
2465                 goto out_err;
2466         }
2467
2468         mntroot = nfs_fs_mount_common(server, flags, dev_name, &mount_info, nfs_mod);
2469         dprintk("<-- nfs_xdev_mount_common() = 0\n");
2470 out:
2471         return mntroot;
2472
2473 out_err:
2474         dprintk("<-- nfs_xdev_mount_common() = %d [error]\n", error);
2475         goto out;
2476 }
2477
2478 #ifdef CONFIG_NFS_V4
2479
2480 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2481 {
2482         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2483                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2484 }
2485
2486 /*
2487  * Validate NFSv4 mount options
2488  */
2489 static int nfs4_validate_mount_data(void *options,
2490                                     struct nfs_parsed_mount_data *args,
2491                                     const char *dev_name)
2492 {
2493         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2494         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2495         char *c;
2496
2497         if (data == NULL)
2498                 goto out_no_data;
2499
2500         args->version = 4;
2501
2502         switch (data->version) {
2503         case 1:
2504                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2505                         goto out_no_address;
2506                 if (data->host_addrlen == 0)
2507                         goto out_no_address;
2508                 args->nfs_server.addrlen = data->host_addrlen;
2509                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2510                         return -EFAULT;
2511                 if (!nfs_verify_server_address(sap))
2512                         goto out_no_address;
2513
2514                 if (data->auth_flavourlen) {
2515                         if (data->auth_flavourlen > 1)
2516                                 goto out_inval_auth;
2517                         if (copy_from_user(&args->auth_flavors[0],
2518                                            data->auth_flavours,
2519                                            sizeof(args->auth_flavors[0])))
2520                                 return -EFAULT;
2521                 }
2522
2523                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2524                 if (IS_ERR(c))
2525                         return PTR_ERR(c);
2526                 args->nfs_server.hostname = c;
2527
2528                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2529                 if (IS_ERR(c))
2530                         return PTR_ERR(c);
2531                 args->nfs_server.export_path = c;
2532                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2533
2534                 c = strndup_user(data->client_addr.data, 16);
2535                 if (IS_ERR(c))
2536                         return PTR_ERR(c);
2537                 args->client_address = c;
2538
2539                 /*
2540                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2541                  * can deal with.
2542                  */
2543
2544                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2545                 args->rsize     = data->rsize;
2546                 args->wsize     = data->wsize;
2547                 args->timeo     = data->timeo;
2548                 args->retrans   = data->retrans;
2549                 args->acregmin  = data->acregmin;
2550                 args->acregmax  = data->acregmax;
2551                 args->acdirmin  = data->acdirmin;
2552                 args->acdirmax  = data->acdirmax;
2553                 args->nfs_server.protocol = data->proto;
2554                 nfs_validate_transport_protocol(args);
2555
2556                 break;
2557         default:
2558                 return NFS_TEXT_DATA;
2559         }
2560
2561         return 0;
2562
2563 out_no_data:
2564         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2565         return -EINVAL;
2566
2567 out_inval_auth:
2568         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2569                  data->auth_flavourlen);
2570         return -EINVAL;
2571
2572 out_no_address:
2573         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2574         return -EINVAL;
2575 }
2576
2577 #endif /* CONFIG_NFS_V4 */