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   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/smp_lock.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/mnt_namespace.h>
  46 #include <linux/namei.h>
  47 #include <linux/nfs_idmap.h>
  48 #include <linux/vfs.h>
  49 #include <linux/inet.h>
  50 #include <linux/in6.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56
  57 #include <asm/system.h>
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66
  67 #define NFSDBG_FACILITY         NFSDBG_VFS
  68
  69 enum {
  70         /* Mount options that take no arguments */
  71         Opt_soft, Opt_hard,
  72         Opt_posix, Opt_noposix,
  73         Opt_cto, Opt_nocto,
  74         Opt_ac, Opt_noac,
  75         Opt_lock, Opt_nolock,
  76         Opt_v2, Opt_v3, Opt_v4,
  77         Opt_udp, Opt_tcp, Opt_rdma,
  78         Opt_acl, Opt_noacl,
  79         Opt_rdirplus, Opt_nordirplus,
  80         Opt_sharecache, Opt_nosharecache,
  81         Opt_resvport, Opt_noresvport,
  82         Opt_fscache, Opt_nofscache,
  83
  84         /* Mount options that take integer arguments */
  85         Opt_port,
  86         Opt_rsize, Opt_wsize, Opt_bsize,
  87         Opt_timeo, Opt_retrans,
  88         Opt_acregmin, Opt_acregmax,
  89         Opt_acdirmin, Opt_acdirmax,
  90         Opt_actimeo,
  91         Opt_namelen,
  92         Opt_mountport,
  93         Opt_mountvers,
  94         Opt_nfsvers,
  95         Opt_minorversion,
  96
  97         /* Mount options that take string arguments */
  98         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
  99         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 100         Opt_lookupcache,
 101         Opt_fscache_uniq,
 102
 103         /* Special mount options */
 104         Opt_userspace, Opt_deprecated, Opt_sloppy,
 105
 106         Opt_err
 107 };
 108
 109 static const match_table_t nfs_mount_option_tokens = {
 110         { Opt_userspace, "bg" },
 111         { Opt_userspace, "fg" },
 112         { Opt_userspace, "retry=%s" },
 113
 114         { Opt_sloppy, "sloppy" },
 115
 116         { Opt_soft, "soft" },
 117         { Opt_hard, "hard" },
 118         { Opt_deprecated, "intr" },
 119         { Opt_deprecated, "nointr" },
 120         { Opt_posix, "posix" },
 121         { Opt_noposix, "noposix" },
 122         { Opt_cto, "cto" },
 123         { Opt_nocto, "nocto" },
 124         { Opt_ac, "ac" },
 125         { Opt_noac, "noac" },
 126         { Opt_lock, "lock" },
 127         { Opt_nolock, "nolock" },
 128         { Opt_v2, "v2" },
 129         { Opt_v3, "v3" },
 130         { Opt_v4, "v4" },
 131         { Opt_udp, "udp" },
 132         { Opt_tcp, "tcp" },
 133         { Opt_rdma, "rdma" },
 134         { Opt_acl, "acl" },
 135         { Opt_noacl, "noacl" },
 136         { Opt_rdirplus, "rdirplus" },
 137         { Opt_nordirplus, "nordirplus" },
 138         { Opt_sharecache, "sharecache" },
 139         { Opt_nosharecache, "nosharecache" },
 140         { Opt_resvport, "resvport" },
 141         { Opt_noresvport, "noresvport" },
 142         { Opt_fscache, "fsc" },
 143         { Opt_fscache_uniq, "fsc=%s" },
 144         { Opt_nofscache, "nofsc" },
 145
 146         { Opt_port, "port=%s" },
 147         { Opt_rsize, "rsize=%s" },
 148         { Opt_wsize, "wsize=%s" },
 149         { Opt_bsize, "bsize=%s" },
 150         { Opt_timeo, "timeo=%s" },
 151         { Opt_retrans, "retrans=%s" },
 152         { Opt_acregmin, "acregmin=%s" },
 153         { Opt_acregmax, "acregmax=%s" },
 154         { Opt_acdirmin, "acdirmin=%s" },
 155         { Opt_acdirmax, "acdirmax=%s" },
 156         { Opt_actimeo, "actimeo=%s" },
 157         { Opt_namelen, "namlen=%s" },
 158         { Opt_mountport, "mountport=%s" },
 159         { Opt_mountvers, "mountvers=%s" },
 160         { Opt_nfsvers, "nfsvers=%s" },
 161         { Opt_nfsvers, "vers=%s" },
 162         { Opt_minorversion, "minorversion=%s" },
 163
 164         { Opt_sec, "sec=%s" },
 165         { Opt_proto, "proto=%s" },
 166         { Opt_mountproto, "mountproto=%s" },
 167         { Opt_addr, "addr=%s" },
 168         { Opt_clientaddr, "clientaddr=%s" },
 169         { Opt_mounthost, "mounthost=%s" },
 170         { Opt_mountaddr, "mountaddr=%s" },
 171
 172         { Opt_lookupcache, "lookupcache=%s" },
 173
 174         { Opt_err, NULL }
 175 };
 176
 177 enum {
 178         Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
 179
 180         Opt_xprt_err
 181 };
 182
 183 static const match_table_t nfs_xprt_protocol_tokens = {
 184         { Opt_xprt_udp, "udp" },
 185         { Opt_xprt_tcp, "tcp" },
 186         { Opt_xprt_rdma, "rdma" },
 187
 188         { Opt_xprt_err, NULL }
 189 };
 190
 191 enum {
 192         Opt_sec_none, Opt_sec_sys,
 193         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 194         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 195         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 196
 197         Opt_sec_err
 198 };
 199
 200 static const match_table_t nfs_secflavor_tokens = {
 201         { Opt_sec_none, "none" },
 202         { Opt_sec_none, "null" },
 203         { Opt_sec_sys, "sys" },
 204
 205         { Opt_sec_krb5, "krb5" },
 206         { Opt_sec_krb5i, "krb5i" },
 207         { Opt_sec_krb5p, "krb5p" },
 208
 209         { Opt_sec_lkey, "lkey" },
 210         { Opt_sec_lkeyi, "lkeyi" },
 211         { Opt_sec_lkeyp, "lkeyp" },
 212
 213         { Opt_sec_spkm, "spkm3" },
 214         { Opt_sec_spkmi, "spkm3i" },
 215         { Opt_sec_spkmp, "spkm3p" },
 216
 217         { Opt_sec_err, NULL }
 218 };
 219
 220 enum {
 221         Opt_lookupcache_all, Opt_lookupcache_positive,
 222         Opt_lookupcache_none,
 223
 224         Opt_lookupcache_err
 225 };
 226
 227 static match_table_t nfs_lookupcache_tokens = {
 228         { Opt_lookupcache_all, "all" },
 229         { Opt_lookupcache_positive, "pos" },
 230         { Opt_lookupcache_positive, "positive" },
 231         { Opt_lookupcache_none, "none" },
 232
 233         { Opt_lookupcache_err, NULL }
 234 };
 235
 236
 237 static void nfs_umount_begin(struct super_block *);
 238 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 239 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 240 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 241 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 242 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 243                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 244 static void nfs_kill_super(struct super_block *);
 245 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 246
 247 static struct file_system_type nfs_fs_type = {
 248         .owner          = THIS_MODULE,
 249         .name           = "nfs",
 250         .get_sb         = nfs_get_sb,
 251         .kill_sb        = nfs_kill_super,
 252         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 253 };
 254
 255 struct file_system_type nfs_xdev_fs_type = {
 256         .owner          = THIS_MODULE,
 257         .name           = "nfs",
 258         .get_sb         = nfs_xdev_get_sb,
 259         .kill_sb        = nfs_kill_super,
 260         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 261 };
 262
 263 static const struct super_operations nfs_sops = {
 264         .alloc_inode    = nfs_alloc_inode,
 265         .destroy_inode  = nfs_destroy_inode,
 266         .write_inode    = nfs_write_inode,
 267         .statfs         = nfs_statfs,
 268         .clear_inode    = nfs_clear_inode,
 269         .umount_begin   = nfs_umount_begin,
 270         .show_options   = nfs_show_options,
 271         .show_stats     = nfs_show_stats,
 272         .remount_fs     = nfs_remount,
 273 };
 274
 275 #ifdef CONFIG_NFS_V4
 276 static int nfs4_validate_text_mount_data(void *options,
 277         struct nfs_parsed_mount_data *args, const char *dev_name);
 278 static int nfs4_try_mount(int flags, const char *dev_name,
 279         struct nfs_parsed_mount_data *data, struct vfsmount *mnt);
 280 static int nfs4_get_sb(struct file_system_type *fs_type,
 281         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 282 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
 283         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 284 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 285         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 286 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 287         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 288 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
 289         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 290 static void nfs4_kill_super(struct super_block *sb);
 291
 292 static struct file_system_type nfs4_fs_type = {
 293         .owner          = THIS_MODULE,
 294         .name           = "nfs4",
 295         .get_sb         = nfs4_get_sb,
 296         .kill_sb        = nfs4_kill_super,
 297         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 298 };
 299
 300 static struct file_system_type nfs4_remote_fs_type = {
 301         .owner          = THIS_MODULE,
 302         .name           = "nfs4",
 303         .get_sb         = nfs4_remote_get_sb,
 304         .kill_sb        = nfs4_kill_super,
 305         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 306 };
 307
 308 struct file_system_type nfs4_xdev_fs_type = {
 309         .owner          = THIS_MODULE,
 310         .name           = "nfs4",
 311         .get_sb         = nfs4_xdev_get_sb,
 312         .kill_sb        = nfs4_kill_super,
 313         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 314 };
 315
 316 static struct file_system_type nfs4_remote_referral_fs_type = {
 317         .owner          = THIS_MODULE,
 318         .name           = "nfs4",
 319         .get_sb         = nfs4_remote_referral_get_sb,
 320         .kill_sb        = nfs4_kill_super,
 321         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 322 };
 323
 324 struct file_system_type nfs4_referral_fs_type = {
 325         .owner          = THIS_MODULE,
 326         .name           = "nfs4",
 327         .get_sb         = nfs4_referral_get_sb,
 328         .kill_sb        = nfs4_kill_super,
 329         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 330 };
 331
 332 static const struct super_operations nfs4_sops = {
 333         .alloc_inode    = nfs_alloc_inode,
 334         .destroy_inode  = nfs_destroy_inode,
 335         .write_inode    = nfs_write_inode,
 336         .statfs         = nfs_statfs,
 337         .clear_inode    = nfs4_clear_inode,
 338         .umount_begin   = nfs_umount_begin,
 339         .show_options   = nfs_show_options,
 340         .show_stats     = nfs_show_stats,
 341         .remount_fs     = nfs_remount,
 342 };
 343 #endif
 344
 345 static struct shrinker acl_shrinker = {
 346         .shrink         = nfs_access_cache_shrinker,
 347         .seeks          = DEFAULT_SEEKS,
 348 };
 349
 350 /*
 351  * Register the NFS filesystems
 352  */
 353 int __init register_nfs_fs(void)
 354 {
 355         int ret;
 356
 357         ret = register_filesystem(&nfs_fs_type);
 358         if (ret < 0)
 359                 goto error_0;
 360
 361         ret = nfs_register_sysctl();
 362         if (ret < 0)
 363                 goto error_1;
 364 #ifdef CONFIG_NFS_V4
 365         ret = register_filesystem(&nfs4_fs_type);
 366         if (ret < 0)
 367                 goto error_2;
 368 #endif
 369         register_shrinker(&acl_shrinker);
 370         return 0;
 371
 372 #ifdef CONFIG_NFS_V4
 373 error_2:
 374         nfs_unregister_sysctl();
 375 #endif
 376 error_1:
 377         unregister_filesystem(&nfs_fs_type);
 378 error_0:
 379         return ret;
 380 }
 381
 382 /*
 383  * Unregister the NFS filesystems
 384  */
 385 void __exit unregister_nfs_fs(void)
 386 {
 387         unregister_shrinker(&acl_shrinker);
 388 #ifdef CONFIG_NFS_V4
 389         unregister_filesystem(&nfs4_fs_type);
 390 #endif
 391         nfs_unregister_sysctl();
 392         unregister_filesystem(&nfs_fs_type);
 393 }
 394
 395 void nfs_sb_active(struct super_block *sb)
 396 {
 397         struct nfs_server *server = NFS_SB(sb);
 398
 399         if (atomic_inc_return(&server->active) == 1)
 400                 atomic_inc(&sb->s_active);
 401 }
 402
 403 void nfs_sb_deactive(struct super_block *sb)
 404 {
 405         struct nfs_server *server = NFS_SB(sb);
 406
 407         if (atomic_dec_and_test(&server->active))
 408                 deactivate_super(sb);
 409 }
 410
 411 /*
 412  * Deliver file system statistics to userspace
 413  */
 414 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 415 {
 416         struct nfs_server *server = NFS_SB(dentry->d_sb);
 417         unsigned char blockbits;
 418         unsigned long blockres;
 419         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 420         struct nfs_fattr fattr;
 421         struct nfs_fsstat res = {
 422                         .fattr = &fattr,
 423         };
 424         int error;
 425
 426         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 427         if (error < 0)
 428                 goto out_err;
 429         buf->f_type = NFS_SUPER_MAGIC;
 430
 431         /*
 432          * Current versions of glibc do not correctly handle the
 433          * case where f_frsize != f_bsize.  Eventually we want to
 434          * report the value of wtmult in this field.
 435          */
 436         buf->f_frsize = dentry->d_sb->s_blocksize;
 437
 438         /*
 439          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 440          * are reported in units of f_frsize.  Linux hasn't had
 441          * an f_frsize field in its statfs struct until recently,
 442          * thus historically Linux's sys_statfs reports these
 443          * fields in units of f_bsize.
 444          */
 445         buf->f_bsize = dentry->d_sb->s_blocksize;
 446         blockbits = dentry->d_sb->s_blocksize_bits;
 447         blockres = (1 << blockbits) - 1;
 448         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 449         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 450         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 451
 452         buf->f_files = res.tfiles;
 453         buf->f_ffree = res.afiles;
 454
 455         buf->f_namelen = server->namelen;
 456
 457         return 0;
 458
 459  out_err:
 460         dprintk("%s: statfs error = %d\n", __func__, -error);
 461         return error;
 462 }
 463
 464 /*
 465  * Map the security flavour number to a name
 466  */
 467 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 468 {
 469         static const struct {
 470                 rpc_authflavor_t flavour;
 471                 const char *str;
 472         } sec_flavours[] = {
 473                 { RPC_AUTH_NULL, "null" },
 474                 { RPC_AUTH_UNIX, "sys" },
 475                 { RPC_AUTH_GSS_KRB5, "krb5" },
 476                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 477                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 478                 { RPC_AUTH_GSS_LKEY, "lkey" },
 479                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 480                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 481                 { RPC_AUTH_GSS_SPKM, "spkm" },
 482                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 483                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 484                 { UINT_MAX, "unknown" }
 485         };
 486         int i;
 487
 488         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 489                 if (sec_flavours[i].flavour == flavour)
 490                         break;
 491         }
 492         return sec_flavours[i].str;
 493 }
 494
 495 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 496                                     int showdefaults)
 497 {
 498         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 499
 500         switch (sap->sa_family) {
 501         case AF_INET: {
 502                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 503                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 504                 break;
 505         }
 506         case AF_INET6: {
 507                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 508                 seq_printf(m, ",mountaddr=%pI6", &sin6->sin6_addr);
 509                 break;
 510         }
 511         default:
 512                 if (showdefaults)
 513                         seq_printf(m, ",mountaddr=unspecified");
 514         }
 515
 516         if (nfss->mountd_version || showdefaults)
 517                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 518         if (nfss->mountd_port || showdefaults)
 519                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 520
 521         switch (nfss->mountd_protocol) {
 522         case IPPROTO_UDP:
 523                 seq_printf(m, ",mountproto=udp");
 524                 break;
 525         case IPPROTO_TCP:
 526                 seq_printf(m, ",mountproto=tcp");
 527                 break;
 528         default:
 529                 if (showdefaults)
 530                         seq_printf(m, ",mountproto=auto");
 531         }
 532 }
 533
 534 /*
 535  * Describe the mount options in force on this server representation
 536  */
 537 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 538                                    int showdefaults)
 539 {
 540         static const struct proc_nfs_info {
 541                 int flag;
 542                 const char *str;
 543                 const char *nostr;
 544         } nfs_info[] = {
 545                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 546                 { NFS_MOUNT_POSIX, ",posix", "" },
 547                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 548                 { NFS_MOUNT_NOAC, ",noac", "" },
 549                 { NFS_MOUNT_NONLM, ",nolock", "" },
 550                 { NFS_MOUNT_NOACL, ",noacl", "" },
 551                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 552                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 553                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 554                 { 0, NULL, NULL }
 555         };
 556         const struct proc_nfs_info *nfs_infop;
 557         struct nfs_client *clp = nfss->nfs_client;
 558         u32 version = clp->rpc_ops->version;
 559
 560         seq_printf(m, ",vers=%u", version);
 561         seq_printf(m, ",rsize=%u", nfss->rsize);
 562         seq_printf(m, ",wsize=%u", nfss->wsize);
 563         if (nfss->bsize != 0)
 564                 seq_printf(m, ",bsize=%u", nfss->bsize);
 565         seq_printf(m, ",namlen=%u", nfss->namelen);
 566         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 567                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 568         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 569                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 570         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 571                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 572         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 573                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 574         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 575                 if (nfss->flags & nfs_infop->flag)
 576                         seq_puts(m, nfs_infop->str);
 577                 else
 578                         seq_puts(m, nfs_infop->nostr);
 579         }
 580         seq_printf(m, ",proto=%s",
 581                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 582         if (version == 4) {
 583                 if (nfss->port != NFS_PORT)
 584                         seq_printf(m, ",port=%u", nfss->port);
 585         } else
 586                 if (nfss->port)
 587                         seq_printf(m, ",port=%u", nfss->port);
 588
 589         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 590         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 591         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 592
 593         if (version != 4)
 594                 nfs_show_mountd_options(m, nfss, showdefaults);
 595
 596 #ifdef CONFIG_NFS_V4
 597         if (clp->rpc_ops->version == 4)
 598                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 599 #endif
 600         if (nfss->options & NFS_OPTION_FSCACHE)
 601                 seq_printf(m, ",fsc");
 602 }
 603
 604 /*
 605  * Describe the mount options on this VFS mountpoint
 606  */
 607 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 608 {
 609         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 610
 611         nfs_show_mount_options(m, nfss, 0);
 612
 613         seq_printf(m, ",addr=%s",
 614                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 615                                                         RPC_DISPLAY_ADDR));
 616
 617         return 0;
 618 }
 619
 620 /*
 621  * Present statistical information for this VFS mountpoint
 622  */
 623 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 624 {
 625         int i, cpu;
 626         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 627         struct rpc_auth *auth = nfss->client->cl_auth;
 628         struct nfs_iostats totals = { };
 629
 630         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 631
 632         /*
 633          * Display all mount option settings
 634          */
 635         seq_printf(m, "\n\topts:\t");
 636         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 637         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 638         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 639         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 640         nfs_show_mount_options(m, nfss, 1);
 641
 642         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 643
 644         seq_printf(m, "\n\tcaps:\t");
 645         seq_printf(m, "caps=0x%x", nfss->caps);
 646         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 647         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 648         seq_printf(m, ",bsize=%u", nfss->bsize);
 649         seq_printf(m, ",namlen=%u", nfss->namelen);
 650
 651 #ifdef CONFIG_NFS_V4
 652         if (nfss->nfs_client->rpc_ops->version == 4) {
 653                 seq_printf(m, "\n\tnfsv4:\t");
 654                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 655                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 656                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 657         }
 658 #endif
 659
 660         /*
 661          * Display security flavor in effect for this mount
 662          */
 663         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 664         if (auth->au_flavor)
 665                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 666
 667         /*
 668          * Display superblock I/O counters
 669          */
 670         for_each_possible_cpu(cpu) {
 671                 struct nfs_iostats *stats;
 672
 673                 preempt_disable();
 674                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 675
 676                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 677                         totals.events[i] += stats->events[i];
 678                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 679                         totals.bytes[i] += stats->bytes[i];
 680 #ifdef CONFIG_NFS_FSCACHE
 681                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 682                         totals.fscache[i] += stats->fscache[i];
 683 #endif
 684
 685                 preempt_enable();
 686         }
 687
 688         seq_printf(m, "\n\tevents:\t");
 689         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 690                 seq_printf(m, "%lu ", totals.events[i]);
 691         seq_printf(m, "\n\tbytes:\t");
 692         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 693                 seq_printf(m, "%Lu ", totals.bytes[i]);
 694 #ifdef CONFIG_NFS_FSCACHE
 695         if (nfss->options & NFS_OPTION_FSCACHE) {
 696                 seq_printf(m, "\n\tfsc:\t");
 697                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 698                         seq_printf(m, "%Lu ", totals.bytes[i]);
 699         }
 700 #endif
 701         seq_printf(m, "\n");
 702
 703         rpc_print_iostats(m, nfss->client);
 704
 705         return 0;
 706 }
 707
 708 /*
 709  * Begin unmount by attempting to remove all automounted mountpoints we added
 710  * in response to xdev traversals and referrals
 711  */
 712 static void nfs_umount_begin(struct super_block *sb)
 713 {
 714         struct nfs_server *server;
 715         struct rpc_clnt *rpc;
 716
 717         server = NFS_SB(sb);
 718         /* -EIO all pending I/O */
 719         rpc = server->client_acl;
 720         if (!IS_ERR(rpc))
 721                 rpc_killall_tasks(rpc);
 722         rpc = server->client;
 723         if (!IS_ERR(rpc))
 724                 rpc_killall_tasks(rpc);
 725 }
 726
 727 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
 728 {
 729         struct nfs_parsed_mount_data *data;
 730
 731         data = kzalloc(sizeof(*data), GFP_KERNEL);
 732         if (data) {
 733                 data->rsize             = NFS_MAX_FILE_IO_SIZE;
 734                 data->wsize             = NFS_MAX_FILE_IO_SIZE;
 735                 data->acregmin          = NFS_DEF_ACREGMIN;
 736                 data->acregmax          = NFS_DEF_ACREGMAX;
 737                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 738                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 739                 data->mount_server.port = NFS_UNSPEC_PORT;
 740                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 741                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 742                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 743                 data->auth_flavor_len   = 1;
 744                 data->version           = version;
 745                 data->minorversion      = 0;
 746         }
 747         return data;
 748 }
 749
 750 /*
 751  * Sanity-check a server address provided by the mount command.
 752  *
 753  * Address family must be initialized, and address must not be
 754  * the ANY address for that family.
 755  */
 756 static int nfs_verify_server_address(struct sockaddr *addr)
 757 {
 758         switch (addr->sa_family) {
 759         case AF_INET: {
 760                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 761                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 762         }
 763         case AF_INET6: {
 764                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 765                 return !ipv6_addr_any(sa);
 766         }
 767         }
 768
 769         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 770         return 0;
 771 }
 772
 773 /*
 774  * Select between a default port value and a user-specified port value.
 775  * If a zero value is set, then autobind will be used.
 776  */
 777 static void nfs_set_port(struct sockaddr *sap, int *port,
 778                                  const unsigned short default_port)
 779 {
 780         if (*port == NFS_UNSPEC_PORT)
 781                 *port = default_port;
 782
 783         rpc_set_port(sap, *port);
 784 }
 785
 786 /*
 787  * Sanity check the NFS transport protocol.
 788  *
 789  */
 790 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 791 {
 792         switch (mnt->nfs_server.protocol) {
 793         case XPRT_TRANSPORT_UDP:
 794         case XPRT_TRANSPORT_TCP:
 795         case XPRT_TRANSPORT_RDMA:
 796                 break;
 797         default:
 798                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 799         }
 800 }
 801
 802 /*
 803  * For text based NFSv2/v3 mounts, the mount protocol transport default
 804  * settings should depend upon the specified NFS transport.
 805  */
 806 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 807 {
 808         nfs_validate_transport_protocol(mnt);
 809
 810         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 811             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 812                         return;
 813         switch (mnt->nfs_server.protocol) {
 814         case XPRT_TRANSPORT_UDP:
 815                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 816                 break;
 817         case XPRT_TRANSPORT_TCP:
 818         case XPRT_TRANSPORT_RDMA:
 819                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 820         }
 821 }
 822
 823 /*
 824  * Parse the value of the 'sec=' option.
 825  */
 826 static int nfs_parse_security_flavors(char *value,
 827                                       struct nfs_parsed_mount_data *mnt)
 828 {
 829         substring_t args[MAX_OPT_ARGS];
 830
 831         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 832
 833         switch (match_token(value, nfs_secflavor_tokens, args)) {
 834         case Opt_sec_none:
 835                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 836                 break;
 837         case Opt_sec_sys:
 838                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 839                 break;
 840         case Opt_sec_krb5:
 841                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 842                 break;
 843         case Opt_sec_krb5i:
 844                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 845                 break;
 846         case Opt_sec_krb5p:
 847                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 848                 break;
 849         case Opt_sec_lkey:
 850                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 851                 break;
 852         case Opt_sec_lkeyi:
 853                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 854                 break;
 855         case Opt_sec_lkeyp:
 856                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 857                 break;
 858         case Opt_sec_spkm:
 859                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
 860                 break;
 861         case Opt_sec_spkmi:
 862                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
 863                 break;
 864         case Opt_sec_spkmp:
 865                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
 866                 break;
 867         default:
 868                 return 0;
 869         }
 870
 871         mnt->auth_flavor_len = 1;
 872         return 1;
 873 }
 874
 875 /*
 876  * Error-check and convert a string of mount options from user space into
 877  * a data structure.  The whole mount string is processed; bad options are
 878  * skipped as they are encountered.  If there were no errors, return 1;
 879  * otherwise return 0 (zero).
 880  */
 881 static int nfs_parse_mount_options(char *raw,
 882                                    struct nfs_parsed_mount_data *mnt)
 883 {
 884         char *p, *string, *secdata;
 885         int rc, sloppy = 0, invalid_option = 0;
 886
 887         if (!raw) {
 888                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 889                 return 1;
 890         }
 891         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 892
 893         secdata = alloc_secdata();
 894         if (!secdata)
 895                 goto out_nomem;
 896
 897         rc = security_sb_copy_data(raw, secdata);
 898         if (rc)
 899                 goto out_security_failure;
 900
 901         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 902         if (rc)
 903                 goto out_security_failure;
 904
 905         free_secdata(secdata);
 906
 907         while ((p = strsep(&raw, ",")) != NULL) {
 908                 substring_t args[MAX_OPT_ARGS];
 909                 unsigned long option;
 910                 int token;
 911
 912                 if (!*p)
 913                         continue;
 914
 915                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 916
 917                 token = match_token(p, nfs_mount_option_tokens, args);
 918                 switch (token) {
 919
 920                 /*
 921                  * boolean options:  foo/nofoo
 922                  */
 923                 case Opt_soft:
 924                         mnt->flags |= NFS_MOUNT_SOFT;
 925                         break;
 926                 case Opt_hard:
 927                         mnt->flags &= ~NFS_MOUNT_SOFT;
 928                         break;
 929                 case Opt_posix:
 930                         mnt->flags |= NFS_MOUNT_POSIX;
 931                         break;
 932                 case Opt_noposix:
 933                         mnt->flags &= ~NFS_MOUNT_POSIX;
 934                         break;
 935                 case Opt_cto:
 936                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 937                         break;
 938                 case Opt_nocto:
 939                         mnt->flags |= NFS_MOUNT_NOCTO;
 940                         break;
 941                 case Opt_ac:
 942                         mnt->flags &= ~NFS_MOUNT_NOAC;
 943                         break;
 944                 case Opt_noac:
 945                         mnt->flags |= NFS_MOUNT_NOAC;
 946                         break;
 947                 case Opt_lock:
 948                         mnt->flags &= ~NFS_MOUNT_NONLM;
 949                         break;
 950                 case Opt_nolock:
 951                         mnt->flags |= NFS_MOUNT_NONLM;
 952                         break;
 953                 case Opt_v2:
 954                         mnt->flags &= ~NFS_MOUNT_VER3;
 955                         mnt->version = 2;
 956                         break;
 957                 case Opt_v3:
 958                         mnt->flags |= NFS_MOUNT_VER3;
 959                         mnt->version = 3;
 960                         break;
 961 #ifdef CONFIG_NFS_V4
 962                 case Opt_v4:
 963                         mnt->flags &= ~NFS_MOUNT_VER3;
 964                         mnt->version = 4;
 965                         break;
 966 #endif
 967                 case Opt_udp:
 968                         mnt->flags &= ~NFS_MOUNT_TCP;
 969                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 970                         break;
 971                 case Opt_tcp:
 972                         mnt->flags |= NFS_MOUNT_TCP;
 973                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 974                         break;
 975                 case Opt_rdma:
 976                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 977                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 978                         xprt_load_transport(p);
 979                         break;
 980                 case Opt_acl:
 981                         mnt->flags &= ~NFS_MOUNT_NOACL;
 982                         break;
 983                 case Opt_noacl:
 984                         mnt->flags |= NFS_MOUNT_NOACL;
 985                         break;
 986                 case Opt_rdirplus:
 987                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 988                         break;
 989                 case Opt_nordirplus:
 990                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 991                         break;
 992                 case Opt_sharecache:
 993                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 994                         break;
 995                 case Opt_nosharecache:
 996                         mnt->flags |= NFS_MOUNT_UNSHARED;
 997                         break;
 998                 case Opt_resvport:
 999                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1000                         break;
1001                 case Opt_noresvport:
1002                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1003                         break;
1004                 case Opt_fscache:
1005                         mnt->options |= NFS_OPTION_FSCACHE;
1006                         kfree(mnt->fscache_uniq);
1007                         mnt->fscache_uniq = NULL;
1008                         break;
1009                 case Opt_nofscache:
1010                         mnt->options &= ~NFS_OPTION_FSCACHE;
1011                         kfree(mnt->fscache_uniq);
1012                         mnt->fscache_uniq = NULL;
1013                         break;
1014                 case Opt_fscache_uniq:
1015                         string = match_strdup(args);
1016                         if (!string)
1017                                 goto out_nomem;
1018                         kfree(mnt->fscache_uniq);
1019                         mnt->fscache_uniq = string;
1020                         mnt->options |= NFS_OPTION_FSCACHE;
1021                         break;
1022
1023                 /*
1024                  * options that take numeric values
1025                  */
1026                 case Opt_port:
1027                         string = match_strdup(args);
1028                         if (string == NULL)
1029                                 goto out_nomem;
1030                         rc = strict_strtoul(string, 10, &option);
1031                         kfree(string);
1032                         if (rc != 0 || option > USHORT_MAX)
1033                                 goto out_invalid_value;
1034                         mnt->nfs_server.port = option;
1035                         break;
1036                 case Opt_rsize:
1037                         string = match_strdup(args);
1038                         if (string == NULL)
1039                                 goto out_nomem;
1040                         rc = strict_strtoul(string, 10, &option);
1041                         kfree(string);
1042                         if (rc != 0)
1043                                 goto out_invalid_value;
1044                         mnt->rsize = option;
1045                         break;
1046                 case Opt_wsize:
1047                         string = match_strdup(args);
1048                         if (string == NULL)
1049                                 goto out_nomem;
1050                         rc = strict_strtoul(string, 10, &option);
1051                         kfree(string);
1052                         if (rc != 0)
1053                                 goto out_invalid_value;
1054                         mnt->wsize = option;
1055                         break;
1056                 case Opt_bsize:
1057                         string = match_strdup(args);
1058                         if (string == NULL)
1059                                 goto out_nomem;
1060                         rc = strict_strtoul(string, 10, &option);
1061                         kfree(string);
1062                         if (rc != 0)
1063                                 goto out_invalid_value;
1064                         mnt->bsize = option;
1065                         break;
1066                 case Opt_timeo:
1067                         string = match_strdup(args);
1068                         if (string == NULL)
1069                                 goto out_nomem;
1070                         rc = strict_strtoul(string, 10, &option);
1071                         kfree(string);
1072                         if (rc != 0 || option == 0)
1073                                 goto out_invalid_value;
1074                         mnt->timeo = option;
1075                         break;
1076                 case Opt_retrans:
1077                         string = match_strdup(args);
1078                         if (string == NULL)
1079                                 goto out_nomem;
1080                         rc = strict_strtoul(string, 10, &option);
1081                         kfree(string);
1082                         if (rc != 0 || option == 0)
1083                                 goto out_invalid_value;
1084                         mnt->retrans = option;
1085                         break;
1086                 case Opt_acregmin:
1087                         string = match_strdup(args);
1088                         if (string == NULL)
1089                                 goto out_nomem;
1090                         rc = strict_strtoul(string, 10, &option);
1091                         kfree(string);
1092                         if (rc != 0)
1093                                 goto out_invalid_value;
1094                         mnt->acregmin = option;
1095                         break;
1096                 case Opt_acregmax:
1097                         string = match_strdup(args);
1098                         if (string == NULL)
1099                                 goto out_nomem;
1100                         rc = strict_strtoul(string, 10, &option);
1101                         kfree(string);
1102                         if (rc != 0)
1103                                 goto out_invalid_value;
1104                         mnt->acregmax = option;
1105                         break;
1106                 case Opt_acdirmin:
1107                         string = match_strdup(args);
1108                         if (string == NULL)
1109                                 goto out_nomem;
1110                         rc = strict_strtoul(string, 10, &option);
1111                         kfree(string);
1112                         if (rc != 0)
1113                                 goto out_invalid_value;
1114                         mnt->acdirmin = option;
1115                         break;
1116                 case Opt_acdirmax:
1117                         string = match_strdup(args);
1118                         if (string == NULL)
1119                                 goto out_nomem;
1120                         rc = strict_strtoul(string, 10, &option);
1121                         kfree(string);
1122                         if (rc != 0)
1123                                 goto out_invalid_value;
1124                         mnt->acdirmax = option;
1125                         break;
1126                 case Opt_actimeo:
1127                         string = match_strdup(args);
1128                         if (string == NULL)
1129                                 goto out_nomem;
1130                         rc = strict_strtoul(string, 10, &option);
1131                         kfree(string);
1132                         if (rc != 0)
1133                                 goto out_invalid_value;
1134                         mnt->acregmin = mnt->acregmax =
1135                         mnt->acdirmin = mnt->acdirmax = option;
1136                         break;
1137                 case Opt_namelen:
1138                         string = match_strdup(args);
1139                         if (string == NULL)
1140                                 goto out_nomem;
1141                         rc = strict_strtoul(string, 10, &option);
1142                         kfree(string);
1143                         if (rc != 0)
1144                                 goto out_invalid_value;
1145                         mnt->namlen = option;
1146                         break;
1147                 case Opt_mountport:
1148                         string = match_strdup(args);
1149                         if (string == NULL)
1150                                 goto out_nomem;
1151                         rc = strict_strtoul(string, 10, &option);
1152                         kfree(string);
1153                         if (rc != 0 || option > USHORT_MAX)
1154                                 goto out_invalid_value;
1155                         mnt->mount_server.port = option;
1156                         break;
1157                 case Opt_mountvers:
1158                         string = match_strdup(args);
1159                         if (string == NULL)
1160                                 goto out_nomem;
1161                         rc = strict_strtoul(string, 10, &option);
1162                         kfree(string);
1163                         if (rc != 0 ||
1164                             option < NFS_MNT_VERSION ||
1165                             option > NFS_MNT3_VERSION)
1166                                 goto out_invalid_value;
1167                         mnt->mount_server.version = option;
1168                         break;
1169                 case Opt_nfsvers:
1170                         string = match_strdup(args);
1171                         if (string == NULL)
1172                                 goto out_nomem;
1173                         rc = strict_strtoul(string, 10, &option);
1174                         kfree(string);
1175                         if (rc != 0)
1176                                 goto out_invalid_value;
1177                         switch (option) {
1178                         case NFS2_VERSION:
1179                                 mnt->flags &= ~NFS_MOUNT_VER3;
1180                                 mnt->version = 2;
1181                                 break;
1182                         case NFS3_VERSION:
1183                                 mnt->flags |= NFS_MOUNT_VER3;
1184                                 mnt->version = 3;
1185                                 break;
1186 #ifdef CONFIG_NFS_V4
1187                         case NFS4_VERSION:
1188                                 mnt->flags &= ~NFS_MOUNT_VER3;
1189                                 mnt->version = 4;
1190                                 break;
1191 #endif
1192                         default:
1193                                 goto out_invalid_value;
1194                         }
1195                         break;
1196                 case Opt_minorversion:
1197                         string = match_strdup(args);
1198                         if (string == NULL)
1199                                 goto out_nomem;
1200                         rc = strict_strtoul(string, 10, &option);
1201                         kfree(string);
1202                         if (rc != 0)
1203                                 goto out_invalid_value;
1204                         if (option > NFS4_MAX_MINOR_VERSION)
1205                                 goto out_invalid_value;
1206                         mnt->minorversion = option;
1207                         break;
1208
1209                 /*
1210                  * options that take text values
1211                  */
1212                 case Opt_sec:
1213                         string = match_strdup(args);
1214                         if (string == NULL)
1215                                 goto out_nomem;
1216                         rc = nfs_parse_security_flavors(string, mnt);
1217                         kfree(string);
1218                         if (!rc) {
1219                                 dfprintk(MOUNT, "NFS:   unrecognized "
1220                                                 "security flavor\n");
1221                                 return 0;
1222                         }
1223                         break;
1224                 case Opt_proto:
1225                         string = match_strdup(args);
1226                         if (string == NULL)
1227                                 goto out_nomem;
1228                         token = match_token(string,
1229                                             nfs_xprt_protocol_tokens, args);
1230
1231                         switch (token) {
1232                         case Opt_xprt_udp:
1233                                 mnt->flags &= ~NFS_MOUNT_TCP;
1234                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1235                                 kfree(string);
1236                                 break;
1237                         case Opt_xprt_tcp:
1238                                 mnt->flags |= NFS_MOUNT_TCP;
1239                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1240                                 kfree(string);
1241                                 break;
1242                         case Opt_xprt_rdma:
1243                                 /* vector side protocols to TCP */
1244                                 mnt->flags |= NFS_MOUNT_TCP;
1245                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1246                                 xprt_load_transport(string);
1247                                 kfree(string);
1248                                 break;
1249                         default:
1250                                 dfprintk(MOUNT, "NFS:   unrecognized "
1251                                                 "transport protocol\n");
1252                                 kfree(string);
1253                                 return 0;
1254                         }
1255                         break;
1256                 case Opt_mountproto:
1257                         string = match_strdup(args);
1258                         if (string == NULL)
1259                                 goto out_nomem;
1260                         token = match_token(string,
1261                                             nfs_xprt_protocol_tokens, args);
1262                         kfree(string);
1263
1264                         switch (token) {
1265                         case Opt_xprt_udp:
1266                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1267                                 break;
1268                         case Opt_xprt_tcp:
1269                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1270                                 break;
1271                         case Opt_xprt_rdma: /* not used for side protocols */
1272                         default:
1273                                 dfprintk(MOUNT, "NFS:   unrecognized "
1274                                                 "transport protocol\n");
1275                                 return 0;
1276                         }
1277                         break;
1278                 case Opt_addr:
1279                         string = match_strdup(args);
1280                         if (string == NULL)
1281                                 goto out_nomem;
1282                         mnt->nfs_server.addrlen =
1283                                 rpc_pton(string, strlen(string),
1284                                         (struct sockaddr *)
1285                                         &mnt->nfs_server.address,
1286                                         sizeof(mnt->nfs_server.address));
1287                         kfree(string);
1288                         if (mnt->nfs_server.addrlen == 0)
1289                                 goto out_invalid_address;
1290                         break;
1291                 case Opt_clientaddr:
1292                         string = match_strdup(args);
1293                         if (string == NULL)
1294                                 goto out_nomem;
1295                         kfree(mnt->client_address);
1296                         mnt->client_address = string;
1297                         break;
1298                 case Opt_mounthost:
1299                         string = match_strdup(args);
1300                         if (string == NULL)
1301                                 goto out_nomem;
1302                         kfree(mnt->mount_server.hostname);
1303                         mnt->mount_server.hostname = string;
1304                         break;
1305                 case Opt_mountaddr:
1306                         string = match_strdup(args);
1307                         if (string == NULL)
1308                                 goto out_nomem;
1309                         mnt->mount_server.addrlen =
1310                                 rpc_pton(string, strlen(string),
1311                                         (struct sockaddr *)
1312                                         &mnt->mount_server.address,
1313                                         sizeof(mnt->mount_server.address));
1314                         kfree(string);
1315                         if (mnt->mount_server.addrlen == 0)
1316                                 goto out_invalid_address;
1317                         break;
1318                 case Opt_lookupcache:
1319                         string = match_strdup(args);
1320                         if (string == NULL)
1321                                 goto out_nomem;
1322                         token = match_token(string,
1323                                         nfs_lookupcache_tokens, args);
1324                         kfree(string);
1325                         switch (token) {
1326                                 case Opt_lookupcache_all:
1327                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1328                                         break;
1329                                 case Opt_lookupcache_positive:
1330                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1331                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1332                                         break;
1333                                 case Opt_lookupcache_none:
1334                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1335                                         break;
1336                                 default:
1337                                         dfprintk(MOUNT, "NFS:   invalid "
1338                                                         "lookupcache argument\n");
1339                                         return 0;
1340                         };
1341                         break;
1342
1343                 /*
1344                  * Special options
1345                  */
1346                 case Opt_sloppy:
1347                         sloppy = 1;
1348                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1349                         break;
1350                 case Opt_userspace:
1351                 case Opt_deprecated:
1352                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1353                                         "'%s'\n", p);
1354                         break;
1355
1356                 default:
1357                         invalid_option = 1;
1358                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1359                                         "'%s'\n", p);
1360                 }
1361         }
1362
1363         if (!sloppy && invalid_option)
1364                 return 0;
1365
1366         return 1;
1367
1368 out_invalid_address:
1369         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1370         return 0;
1371 out_invalid_value:
1372         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1373         return 0;
1374 out_nomem:
1375         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1376         return 0;
1377 out_security_failure:
1378         free_secdata(secdata);
1379         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1380         return 0;
1381 }
1382
1383 /*
1384  * Match the requested auth flavors with the list returned by
1385  * the server.  Returns zero and sets the mount's authentication
1386  * flavor on success; returns -EACCES if server does not support
1387  * the requested flavor.
1388  */
1389 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1390                              struct nfs_mount_request *request)
1391 {
1392         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1393
1394         /*
1395          * Certain releases of Linux's mountd return an empty
1396          * flavor list.  To prevent behavioral regression with
1397          * these servers (ie. rejecting mounts that used to
1398          * succeed), revert to pre-2.6.32 behavior (no checking)
1399          * if the returned flavor list is empty.
1400          */
1401         if (server_authlist_len == 0)
1402                 return 0;
1403
1404         /*
1405          * We avoid sophisticated negotiating here, as there are
1406          * plenty of cases where we can get it wrong, providing
1407          * either too little or too much security.
1408          *
1409          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1410          * flavor listed first.  However, some servers list
1411          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1412          * preferred default, in args->auth_flavors[0] if user
1413          * didn't specify sec= mount option.
1414          */
1415         for (i = 0; i < args->auth_flavor_len; i++)
1416                 for (j = 0; j < server_authlist_len; j++)
1417                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1418                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1419                                         request->auth_flavs[j]);
1420                                 args->auth_flavors[0] = request->auth_flavs[j];
1421                                 return 0;
1422                         }
1423
1424         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1425         nfs_umount(request);
1426         return -EACCES;
1427 }
1428
1429 /*
1430  * Use the remote server's MOUNT service to request the NFS file handle
1431  * corresponding to the provided path.
1432  */
1433 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1434                          struct nfs_fh *root_fh)
1435 {
1436         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1437         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1438         struct nfs_mount_request request = {
1439                 .sap            = (struct sockaddr *)
1440                                                 &args->mount_server.address,
1441                 .dirpath        = args->nfs_server.export_path,
1442                 .protocol       = args->mount_server.protocol,
1443                 .fh             = root_fh,
1444                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1445                 .auth_flav_len  = &server_authlist_len,
1446                 .auth_flavs     = server_authlist,
1447         };
1448         int status;
1449
1450         if (args->mount_server.version == 0) {
1451                 switch (args->version) {
1452                         default:
1453                                 args->mount_server.version = NFS_MNT3_VERSION;
1454                                 break;
1455                         case 2:
1456                                 args->mount_server.version = NFS_MNT_VERSION;
1457                 }
1458         }
1459         request.version = args->mount_server.version;
1460
1461         if (args->mount_server.hostname)
1462                 request.hostname = args->mount_server.hostname;
1463         else
1464                 request.hostname = args->nfs_server.hostname;
1465
1466         /*
1467          * Construct the mount server's address.
1468          */
1469         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1470                 memcpy(request.sap, &args->nfs_server.address,
1471                        args->nfs_server.addrlen);
1472                 args->mount_server.addrlen = args->nfs_server.addrlen;
1473         }
1474         request.salen = args->mount_server.addrlen;
1475         nfs_set_port(request.sap, &args->mount_server.port, 0);
1476
1477         /*
1478          * Now ask the mount server to map our export path
1479          * to a file handle.
1480          */
1481         status = nfs_mount(&request);
1482         if (status != 0) {
1483                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1484                                 request.hostname, status);
1485                 return status;
1486         }
1487
1488         /*
1489          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1490          */
1491         if (args->mount_server.version != NFS_MNT3_VERSION)
1492                 return 0;
1493         return nfs_walk_authlist(args, &request);
1494 }
1495
1496 static int nfs_parse_simple_hostname(const char *dev_name,
1497                                      char **hostname, size_t maxnamlen,
1498                                      char **export_path, size_t maxpathlen)
1499 {
1500         size_t len;
1501         char *colon, *comma;
1502
1503         colon = strchr(dev_name, ':');
1504         if (colon == NULL)
1505                 goto out_bad_devname;
1506
1507         len = colon - dev_name;
1508         if (len > maxnamlen)
1509                 goto out_hostname;
1510
1511         /* N.B. caller will free nfs_server.hostname in all cases */
1512         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1513         if (!*hostname)
1514                 goto out_nomem;
1515
1516         /* kill possible hostname list: not supported */
1517         comma = strchr(*hostname, ',');
1518         if (comma != NULL) {
1519                 if (comma == *hostname)
1520                         goto out_bad_devname;
1521                 *comma = '\0';
1522         }
1523
1524         colon++;
1525         len = strlen(colon);
1526         if (len > maxpathlen)
1527                 goto out_path;
1528         *export_path = kstrndup(colon, len, GFP_KERNEL);
1529         if (!*export_path)
1530                 goto out_nomem;
1531
1532         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1533         return 0;
1534
1535 out_bad_devname:
1536         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1537         return -EINVAL;
1538
1539 out_nomem:
1540         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1541         return -ENOMEM;
1542
1543 out_hostname:
1544         dfprintk(MOUNT, "NFS: server hostname too long\n");
1545         return -ENAMETOOLONG;
1546
1547 out_path:
1548         dfprintk(MOUNT, "NFS: export pathname too long\n");
1549         return -ENAMETOOLONG;
1550 }
1551
1552 /*
1553  * Hostname has square brackets around it because it contains one or
1554  * more colons.  We look for the first closing square bracket, and a
1555  * colon must follow it.
1556  */
1557 static int nfs_parse_protected_hostname(const char *dev_name,
1558                                         char **hostname, size_t maxnamlen,
1559                                         char **export_path, size_t maxpathlen)
1560 {
1561         size_t len;
1562         char *start, *end;
1563
1564         start = (char *)(dev_name + 1);
1565
1566         end = strchr(start, ']');
1567         if (end == NULL)
1568                 goto out_bad_devname;
1569         if (*(end + 1) != ':')
1570                 goto out_bad_devname;
1571
1572         len = end - start;
1573         if (len > maxnamlen)
1574                 goto out_hostname;
1575
1576         /* N.B. caller will free nfs_server.hostname in all cases */
1577         *hostname = kstrndup(start, len, GFP_KERNEL);
1578         if (*hostname == NULL)
1579                 goto out_nomem;
1580
1581         end += 2;
1582         len = strlen(end);
1583         if (len > maxpathlen)
1584                 goto out_path;
1585         *export_path = kstrndup(end, len, GFP_KERNEL);
1586         if (!*export_path)
1587                 goto out_nomem;
1588
1589         return 0;
1590
1591 out_bad_devname:
1592         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1593         return -EINVAL;
1594
1595 out_nomem:
1596         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1597         return -ENOMEM;
1598
1599 out_hostname:
1600         dfprintk(MOUNT, "NFS: server hostname too long\n");
1601         return -ENAMETOOLONG;
1602
1603 out_path:
1604         dfprintk(MOUNT, "NFS: export pathname too long\n");
1605         return -ENAMETOOLONG;
1606 }
1607
1608 /*
1609  * Split "dev_name" into "hostname:export_path".
1610  *
1611  * The leftmost colon demarks the split between the server's hostname
1612  * and the export path.  If the hostname starts with a left square
1613  * bracket, then it may contain colons.
1614  *
1615  * Note: caller frees hostname and export path, even on error.
1616  */
1617 static int nfs_parse_devname(const char *dev_name,
1618                              char **hostname, size_t maxnamlen,
1619                              char **export_path, size_t maxpathlen)
1620 {
1621         if (*dev_name == '[')
1622                 return nfs_parse_protected_hostname(dev_name,
1623                                                     hostname, maxnamlen,
1624                                                     export_path, maxpathlen);
1625
1626         return nfs_parse_simple_hostname(dev_name,
1627                                          hostname, maxnamlen,
1628                                          export_path, maxpathlen);
1629 }
1630
1631 /*
1632  * Validate the NFS2/NFS3 mount data
1633  * - fills in the mount root filehandle
1634  *
1635  * For option strings, user space handles the following behaviors:
1636  *
1637  * + DNS: mapping server host name to IP address ("addr=" option)
1638  *
1639  * + failure mode: how to behave if a mount request can't be handled
1640  *   immediately ("fg/bg" option)
1641  *
1642  * + retry: how often to retry a mount request ("retry=" option)
1643  *
1644  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1645  *   mountproto=tcp after mountproto=udp, and so on
1646  */
1647 static int nfs_validate_mount_data(void *options,
1648                                    struct nfs_parsed_mount_data *args,
1649                                    struct nfs_fh *mntfh,
1650                                    const char *dev_name)
1651 {
1652         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1653         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1654
1655         if (data == NULL)
1656                 goto out_no_data;
1657
1658         switch (data->version) {
1659         case 1:
1660                 data->namlen = 0;
1661         case 2:
1662                 data->bsize = 0;
1663         case 3:
1664                 if (data->flags & NFS_MOUNT_VER3)
1665                         goto out_no_v3;
1666                 data->root.size = NFS2_FHSIZE;
1667                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1668         case 4:
1669                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1670                         goto out_no_sec;
1671         case 5:
1672                 memset(data->context, 0, sizeof(data->context));
1673         case 6:
1674                 if (data->flags & NFS_MOUNT_VER3) {
1675                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1676                                 goto out_invalid_fh;
1677                         mntfh->size = data->root.size;
1678                         args->version = 3;
1679                 } else {
1680                         mntfh->size = NFS2_FHSIZE;
1681                         args->version = 2;
1682                 }
1683
1684
1685                 memcpy(mntfh->data, data->root.data, mntfh->size);
1686                 if (mntfh->size < sizeof(mntfh->data))
1687                         memset(mntfh->data + mntfh->size, 0,
1688                                sizeof(mntfh->data) - mntfh->size);
1689
1690                 /*
1691                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1692                  * can deal with.
1693                  */
1694                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1695                 args->rsize             = data->rsize;
1696                 args->wsize             = data->wsize;
1697                 args->timeo             = data->timeo;
1698                 args->retrans           = data->retrans;
1699                 args->acregmin          = data->acregmin;
1700                 args->acregmax          = data->acregmax;
1701                 args->acdirmin          = data->acdirmin;
1702                 args->acdirmax          = data->acdirmax;
1703
1704                 memcpy(sap, &data->addr, sizeof(data->addr));
1705                 args->nfs_server.addrlen = sizeof(data->addr);
1706                 if (!nfs_verify_server_address(sap))
1707                         goto out_no_address;
1708
1709                 if (!(data->flags & NFS_MOUNT_TCP))
1710                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1711                 /* N.B. caller will free nfs_server.hostname in all cases */
1712                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1713                 args->namlen            = data->namlen;
1714                 args->bsize             = data->bsize;
1715
1716                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1717                         args->auth_flavors[0] = data->pseudoflavor;
1718                 if (!args->nfs_server.hostname)
1719                         goto out_nomem;
1720
1721                 /*
1722                  * The legacy version 6 binary mount data from userspace has a
1723                  * field used only to transport selinux information into the
1724                  * the kernel.  To continue to support that functionality we
1725                  * have a touch of selinux knowledge here in the NFS code. The
1726                  * userspace code converted context=blah to just blah so we are
1727                  * converting back to the full string selinux understands.
1728                  */
1729                 if (data->context[0]){
1730 #ifdef CONFIG_SECURITY_SELINUX
1731                         int rc;
1732                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1733                         if (!opts_str)
1734                                 return -ENOMEM;
1735                         strcpy(opts_str, "context=");
1736                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1737                         strcat(opts_str, &data->context[0]);
1738                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1739                         kfree(opts_str);
1740                         if (rc)
1741                                 return rc;
1742 #else
1743                         return -EINVAL;
1744 #endif
1745                 }
1746
1747                 break;
1748         default: {
1749                 int status;
1750
1751                 if (nfs_parse_mount_options((char *)options, args) == 0)
1752                         return -EINVAL;
1753
1754                 if (!nfs_verify_server_address(sap))
1755                         goto out_no_address;
1756
1757                 if (args->version == 4)
1758 #ifdef CONFIG_NFS_V4
1759                         return nfs4_validate_text_mount_data(options,
1760                                                              args, dev_name);
1761 #else
1762                         goto out_v4_not_compiled;
1763 #endif
1764
1765                 nfs_set_port(sap, &args->nfs_server.port, 0);
1766
1767                 nfs_set_mount_transport_protocol(args);
1768
1769                 status = nfs_parse_devname(dev_name,
1770                                            &args->nfs_server.hostname,
1771                                            PAGE_SIZE,
1772                                            &args->nfs_server.export_path,
1773                                            NFS_MAXPATHLEN);
1774                 if (!status)
1775                         status = nfs_try_mount(args, mntfh);
1776
1777                 kfree(args->nfs_server.export_path);
1778                 args->nfs_server.export_path = NULL;
1779
1780                 if (status)
1781                         return status;
1782
1783                 break;
1784                 }
1785         }
1786
1787 #ifndef CONFIG_NFS_V3
1788         if (args->version == 3)
1789                 goto out_v3_not_compiled;
1790 #endif /* !CONFIG_NFS_V3 */
1791
1792         return 0;
1793
1794 out_no_data:
1795         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1796         return -EINVAL;
1797
1798 out_no_v3:
1799         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1800                  data->version);
1801         return -EINVAL;
1802
1803 out_no_sec:
1804         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1805         return -EINVAL;
1806
1807 #ifndef CONFIG_NFS_V3
1808 out_v3_not_compiled:
1809         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1810         return -EPROTONOSUPPORT;
1811 #endif /* !CONFIG_NFS_V3 */
1812
1813 #ifndef CONFIG_NFS_V4
1814 out_v4_not_compiled:
1815         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1816         return -EPROTONOSUPPORT;
1817 #endif /* !CONFIG_NFS_V4 */
1818
1819 out_nomem:
1820         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1821         return -ENOMEM;
1822
1823 out_no_address:
1824         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1825         return -EINVAL;
1826
1827 out_invalid_fh:
1828         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1829         return -EINVAL;
1830 }
1831
1832 static int
1833 nfs_compare_remount_data(struct nfs_server *nfss,
1834                          struct nfs_parsed_mount_data *data)
1835 {
1836         if (data->flags != nfss->flags ||
1837             data->rsize != nfss->rsize ||
1838             data->wsize != nfss->wsize ||
1839             data->retrans != nfss->client->cl_timeout->to_retries ||
1840             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1841             data->acregmin != nfss->acregmin / HZ ||
1842             data->acregmax != nfss->acregmax / HZ ||
1843             data->acdirmin != nfss->acdirmin / HZ ||
1844             data->acdirmax != nfss->acdirmax / HZ ||
1845             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1846             data->nfs_server.port != nfss->port ||
1847             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1848             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1849                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1850                 return -EINVAL;
1851
1852         return 0;
1853 }
1854
1855 static int
1856 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1857 {
1858         int error;
1859         struct nfs_server *nfss = sb->s_fs_info;
1860         struct nfs_parsed_mount_data *data;
1861         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1862         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1863         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1864
1865         /*
1866          * Userspace mount programs that send binary options generally send
1867          * them populated with default values. We have no way to know which
1868          * ones were explicitly specified. Fall back to legacy behavior and
1869          * just return success.
1870          */
1871         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1872             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1873                                            options->version <= 6))))
1874                 return 0;
1875
1876         data = kzalloc(sizeof(*data), GFP_KERNEL);
1877         if (data == NULL)
1878                 return -ENOMEM;
1879
1880         /* fill out struct with values from existing mount */
1881         data->flags = nfss->flags;
1882         data->rsize = nfss->rsize;
1883         data->wsize = nfss->wsize;
1884         data->retrans = nfss->client->cl_timeout->to_retries;
1885         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1886         data->acregmin = nfss->acregmin / HZ;
1887         data->acregmax = nfss->acregmax / HZ;
1888         data->acdirmin = nfss->acdirmin / HZ;
1889         data->acdirmax = nfss->acdirmax / HZ;
1890         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1891         data->nfs_server.port = nfss->port;
1892         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1893         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1894                 data->nfs_server.addrlen);
1895
1896         /* overwrite those values with any that were specified */
1897         error = nfs_parse_mount_options((char *)options, data);
1898         if (error < 0)
1899                 goto out;
1900
1901         /* compare new mount options with old ones */
1902         error = nfs_compare_remount_data(nfss, data);
1903 out:
1904         kfree(data);
1905         return error;
1906 }
1907
1908 /*
1909  * Initialise the common bits of the superblock
1910  */
1911 static inline void nfs_initialise_sb(struct super_block *sb)
1912 {
1913         struct nfs_server *server = NFS_SB(sb);
1914
1915         sb->s_magic = NFS_SUPER_MAGIC;
1916
1917         /* We probably want something more informative here */
1918         snprintf(sb->s_id, sizeof(sb->s_id),
1919                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1920
1921         if (sb->s_blocksize == 0)
1922                 sb->s_blocksize = nfs_block_bits(server->wsize,
1923                                                  &sb->s_blocksize_bits);
1924
1925         if (server->flags & NFS_MOUNT_NOAC)
1926                 sb->s_flags |= MS_SYNCHRONOUS;
1927
1928         sb->s_bdi = &server->backing_dev_info;
1929
1930         nfs_super_set_maxbytes(sb, server->maxfilesize);
1931 }
1932
1933 /*
1934  * Finish setting up an NFS2/3 superblock
1935  */
1936 static void nfs_fill_super(struct super_block *sb,
1937                            struct nfs_parsed_mount_data *data)
1938 {
1939         struct nfs_server *server = NFS_SB(sb);
1940
1941         sb->s_blocksize_bits = 0;
1942         sb->s_blocksize = 0;
1943         if (data->bsize)
1944                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1945
1946         if (server->nfs_client->rpc_ops->version == 3) {
1947                 /* The VFS shouldn't apply the umask to mode bits. We will do
1948                  * so ourselves when necessary.
1949                  */
1950                 sb->s_flags |= MS_POSIXACL;
1951                 sb->s_time_gran = 1;
1952         }
1953
1954         sb->s_op = &nfs_sops;
1955         nfs_initialise_sb(sb);
1956 }
1957
1958 /*
1959  * Finish setting up a cloned NFS2/3 superblock
1960  */
1961 static void nfs_clone_super(struct super_block *sb,
1962                             const struct super_block *old_sb)
1963 {
1964         struct nfs_server *server = NFS_SB(sb);
1965
1966         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1967         sb->s_blocksize = old_sb->s_blocksize;
1968         sb->s_maxbytes = old_sb->s_maxbytes;
1969
1970         if (server->nfs_client->rpc_ops->version == 3) {
1971                 /* The VFS shouldn't apply the umask to mode bits. We will do
1972                  * so ourselves when necessary.
1973                  */
1974                 sb->s_flags |= MS_POSIXACL;
1975                 sb->s_time_gran = 1;
1976         }
1977
1978         sb->s_op = old_sb->s_op;
1979         nfs_initialise_sb(sb);
1980 }
1981
1982 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1983 {
1984         const struct nfs_server *a = s->s_fs_info;
1985         const struct rpc_clnt *clnt_a = a->client;
1986         const struct rpc_clnt *clnt_b = b->client;
1987
1988         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1989                 goto Ebusy;
1990         if (a->nfs_client != b->nfs_client)
1991                 goto Ebusy;
1992         if (a->flags != b->flags)
1993                 goto Ebusy;
1994         if (a->wsize != b->wsize)
1995                 goto Ebusy;
1996         if (a->rsize != b->rsize)
1997                 goto Ebusy;
1998         if (a->acregmin != b->acregmin)
1999                 goto Ebusy;
2000         if (a->acregmax != b->acregmax)
2001                 goto Ebusy;
2002         if (a->acdirmin != b->acdirmin)
2003                 goto Ebusy;
2004         if (a->acdirmax != b->acdirmax)
2005                 goto Ebusy;
2006         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2007                 goto Ebusy;
2008         return 1;
2009 Ebusy:
2010         return 0;
2011 }
2012
2013 struct nfs_sb_mountdata {
2014         struct nfs_server *server;
2015         int mntflags;
2016 };
2017
2018 static int nfs_set_super(struct super_block *s, void *data)
2019 {
2020         struct nfs_sb_mountdata *sb_mntdata = data;
2021         struct nfs_server *server = sb_mntdata->server;
2022         int ret;
2023
2024         s->s_flags = sb_mntdata->mntflags;
2025         s->s_fs_info = server;
2026         ret = set_anon_super(s, server);
2027         if (ret == 0)
2028                 server->s_dev = s->s_dev;
2029         return ret;
2030 }
2031
2032 static int nfs_compare_super_address(struct nfs_server *server1,
2033                                      struct nfs_server *server2)
2034 {
2035         struct sockaddr *sap1, *sap2;
2036
2037         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2038         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2039
2040         if (sap1->sa_family != sap2->sa_family)
2041                 return 0;
2042
2043         switch (sap1->sa_family) {
2044         case AF_INET: {
2045                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2046                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2047                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2048                         return 0;
2049                 if (sin1->sin_port != sin2->sin_port)
2050                         return 0;
2051                 break;
2052         }
2053         case AF_INET6: {
2054                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2055                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2056                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2057                         return 0;
2058                 if (sin1->sin6_port != sin2->sin6_port)
2059                         return 0;
2060                 break;
2061         }
2062         default:
2063                 return 0;
2064         }
2065
2066         return 1;
2067 }
2068
2069 static int nfs_compare_super(struct super_block *sb, void *data)
2070 {
2071         struct nfs_sb_mountdata *sb_mntdata = data;
2072         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2073         int mntflags = sb_mntdata->mntflags;
2074
2075         if (!nfs_compare_super_address(old, server))
2076                 return 0;
2077         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2078         if (old->flags & NFS_MOUNT_UNSHARED)
2079                 return 0;
2080         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2081                 return 0;
2082         return nfs_compare_mount_options(sb, server, mntflags);
2083 }
2084
2085 static int nfs_bdi_register(struct nfs_server *server)
2086 {
2087         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2088 }
2089
2090 static int nfs_get_sb(struct file_system_type *fs_type,
2091         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2092 {
2093         struct nfs_server *server = NULL;
2094         struct super_block *s;
2095         struct nfs_parsed_mount_data *data;
2096         struct nfs_fh *mntfh;
2097         struct dentry *mntroot;
2098         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2099         struct nfs_sb_mountdata sb_mntdata = {
2100                 .mntflags = flags,
2101         };
2102         int error = -ENOMEM;
2103
2104         data = nfs_alloc_parsed_mount_data(3);
2105         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2106         if (data == NULL || mntfh == NULL)
2107                 goto out_free_fh;
2108
2109         security_init_mnt_opts(&data->lsm_opts);
2110
2111         /* Validate the mount data */
2112         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2113         if (error < 0)
2114                 goto out;
2115
2116 #ifdef CONFIG_NFS_V4
2117         if (data->version == 4) {
2118                 error = nfs4_try_mount(flags, dev_name, data, mnt);
2119                 kfree(data->client_address);
2120                 goto out;
2121         }
2122 #endif  /* CONFIG_NFS_V4 */
2123
2124         /* Get a volume representation */
2125         server = nfs_create_server(data, mntfh);
2126         if (IS_ERR(server)) {
2127                 error = PTR_ERR(server);
2128                 goto out;
2129         }
2130         sb_mntdata.server = server;
2131
2132         if (server->flags & NFS_MOUNT_UNSHARED)
2133                 compare_super = NULL;
2134
2135         /* Get a superblock - note that we may end up sharing one that already exists */
2136         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2137         if (IS_ERR(s)) {
2138                 error = PTR_ERR(s);
2139                 goto out_err_nosb;
2140         }
2141
2142         if (s->s_fs_info != server) {
2143                 nfs_free_server(server);
2144                 server = NULL;
2145         } else {
2146                 error = nfs_bdi_register(server);
2147                 if (error)
2148                         goto error_splat_super;
2149         }
2150
2151         if (!s->s_root) {
2152                 /* initial superblock/root creation */
2153                 nfs_fill_super(s, data);
2154                 nfs_fscache_get_super_cookie(
2155                         s, data ? data->fscache_uniq : NULL, NULL);
2156         }
2157
2158         mntroot = nfs_get_root(s, mntfh);
2159         if (IS_ERR(mntroot)) {
2160                 error = PTR_ERR(mntroot);
2161                 goto error_splat_super;
2162         }
2163
2164         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2165         if (error)
2166                 goto error_splat_root;
2167
2168         s->s_flags |= MS_ACTIVE;
2169         mnt->mnt_sb = s;
2170         mnt->mnt_root = mntroot;
2171         error = 0;
2172
2173 out:
2174         kfree(data->nfs_server.hostname);
2175         kfree(data->mount_server.hostname);
2176         kfree(data->fscache_uniq);
2177         security_free_mnt_opts(&data->lsm_opts);
2178 out_free_fh:
2179         kfree(mntfh);
2180         kfree(data);
2181         return error;
2182
2183 out_err_nosb:
2184         nfs_free_server(server);
2185         goto out;
2186
2187 error_splat_root:
2188         dput(mntroot);
2189 error_splat_super:
2190         deactivate_locked_super(s);
2191         goto out;
2192 }
2193
2194 /*
2195  * Destroy an NFS2/3 superblock
2196  */
2197 static void nfs_kill_super(struct super_block *s)
2198 {
2199         struct nfs_server *server = NFS_SB(s);
2200
2201         kill_anon_super(s);
2202         bdi_unregister(&server->backing_dev_info);
2203         nfs_fscache_release_super_cookie(s);
2204         nfs_free_server(server);
2205 }
2206
2207 /*
2208  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2209  */
2210 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
2211                            const char *dev_name, void *raw_data,
2212                            struct vfsmount *mnt)
2213 {
2214         struct nfs_clone_mount *data = raw_data;
2215         struct super_block *s;
2216         struct nfs_server *server;
2217         struct dentry *mntroot;
2218         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2219         struct nfs_sb_mountdata sb_mntdata = {
2220                 .mntflags = flags,
2221         };
2222         int error;
2223
2224         dprintk("--> nfs_xdev_get_sb()\n");
2225
2226         /* create a new volume representation */
2227         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2228         if (IS_ERR(server)) {
2229                 error = PTR_ERR(server);
2230                 goto out_err_noserver;
2231         }
2232         sb_mntdata.server = server;
2233
2234         if (server->flags & NFS_MOUNT_UNSHARED)
2235                 compare_super = NULL;
2236
2237         /* Get a superblock - note that we may end up sharing one that already exists */
2238         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2239         if (IS_ERR(s)) {
2240                 error = PTR_ERR(s);
2241                 goto out_err_nosb;
2242         }
2243
2244         if (s->s_fs_info != server) {
2245                 nfs_free_server(server);
2246                 server = NULL;
2247         } else {
2248                 error = nfs_bdi_register(server);
2249                 if (error)
2250                         goto error_splat_super;
2251         }
2252
2253         if (!s->s_root) {
2254                 /* initial superblock/root creation */
2255                 nfs_clone_super(s, data->sb);
2256                 nfs_fscache_get_super_cookie(s, NULL, data);
2257         }
2258
2259         mntroot = nfs_get_root(s, data->fh);
2260         if (IS_ERR(mntroot)) {
2261                 error = PTR_ERR(mntroot);
2262                 goto error_splat_super;
2263         }
2264         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2265                 dput(mntroot);
2266                 error = -ESTALE;
2267                 goto error_splat_super;
2268         }
2269
2270         s->s_flags |= MS_ACTIVE;
2271         mnt->mnt_sb = s;
2272         mnt->mnt_root = mntroot;
2273
2274         /* clone any lsm security options from the parent to the new sb */
2275         security_sb_clone_mnt_opts(data->sb, s);
2276
2277         dprintk("<-- nfs_xdev_get_sb() = 0\n");
2278         return 0;
2279
2280 out_err_nosb:
2281         nfs_free_server(server);
2282 out_err_noserver:
2283         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
2284         return error;
2285
2286 error_splat_super:
2287         deactivate_locked_super(s);
2288         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
2289         return error;
2290 }
2291
2292 #ifdef CONFIG_NFS_V4
2293
2294 /*
2295  * Finish setting up a cloned NFS4 superblock
2296  */
2297 static void nfs4_clone_super(struct super_block *sb,
2298                             const struct super_block *old_sb)
2299 {
2300         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2301         sb->s_blocksize = old_sb->s_blocksize;
2302         sb->s_maxbytes = old_sb->s_maxbytes;
2303         sb->s_time_gran = 1;
2304         sb->s_op = old_sb->s_op;
2305         nfs_initialise_sb(sb);
2306 }
2307
2308 /*
2309  * Set up an NFS4 superblock
2310  */
2311 static void nfs4_fill_super(struct super_block *sb)
2312 {
2313         sb->s_time_gran = 1;
2314         sb->s_op = &nfs4_sops;
2315         nfs_initialise_sb(sb);
2316 }
2317
2318 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2319 {
2320         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3);
2321 }
2322
2323 static int nfs4_validate_text_mount_data(void *options,
2324                                          struct nfs_parsed_mount_data *args,
2325                                          const char *dev_name)
2326 {
2327         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2328
2329         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2330
2331         nfs_validate_transport_protocol(args);
2332
2333         nfs4_validate_mount_flags(args);
2334
2335         if (args->version != 4) {
2336                 dfprintk(MOUNT,
2337                          "NFS4: Illegal mount version\n");
2338                 return -EINVAL;
2339         }
2340
2341         if (args->auth_flavor_len > 1) {
2342                 dfprintk(MOUNT,
2343                          "NFS4: Too many RPC auth flavours specified\n");
2344                 return -EINVAL;
2345         }
2346
2347         if (args->client_address == NULL) {
2348                 dfprintk(MOUNT,
2349                          "NFS4: mount program didn't pass callback address\n");
2350                 return -EINVAL;
2351         }
2352
2353         return nfs_parse_devname(dev_name,
2354                                    &args->nfs_server.hostname,
2355                                    NFS4_MAXNAMLEN,
2356                                    &args->nfs_server.export_path,
2357                                    NFS4_MAXPATHLEN);
2358 }
2359
2360 /*
2361  * Validate NFSv4 mount options
2362  */
2363 static int nfs4_validate_mount_data(void *options,
2364                                     struct nfs_parsed_mount_data *args,
2365                                     const char *dev_name)
2366 {
2367         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2368         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2369         char *c;
2370
2371         if (data == NULL)
2372                 goto out_no_data;
2373
2374         switch (data->version) {
2375         case 1:
2376                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2377                         goto out_no_address;
2378                 if (data->host_addrlen == 0)
2379                         goto out_no_address;
2380                 args->nfs_server.addrlen = data->host_addrlen;
2381                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2382                         return -EFAULT;
2383                 if (!nfs_verify_server_address(sap))
2384                         goto out_no_address;
2385
2386                 if (data->auth_flavourlen) {
2387                         if (data->auth_flavourlen > 1)
2388                                 goto out_inval_auth;
2389                         if (copy_from_user(&args->auth_flavors[0],
2390                                            data->auth_flavours,
2391                                            sizeof(args->auth_flavors[0])))
2392                                 return -EFAULT;
2393                 }
2394
2395                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2396                 if (IS_ERR(c))
2397                         return PTR_ERR(c);
2398                 args->nfs_server.hostname = c;
2399
2400                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2401                 if (IS_ERR(c))
2402                         return PTR_ERR(c);
2403                 args->nfs_server.export_path = c;
2404                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2405
2406                 c = strndup_user(data->client_addr.data, 16);
2407                 if (IS_ERR(c))
2408                         return PTR_ERR(c);
2409                 args->client_address = c;
2410
2411                 /*
2412                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2413                  * can deal with.
2414                  */
2415
2416                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2417                 args->rsize     = data->rsize;
2418                 args->wsize     = data->wsize;
2419                 args->timeo     = data->timeo;
2420                 args->retrans   = data->retrans;
2421                 args->acregmin  = data->acregmin;
2422                 args->acregmax  = data->acregmax;
2423                 args->acdirmin  = data->acdirmin;
2424                 args->acdirmax  = data->acdirmax;
2425                 args->nfs_server.protocol = data->proto;
2426                 nfs_validate_transport_protocol(args);
2427
2428                 break;
2429         default:
2430                 if (nfs_parse_mount_options((char *)options, args) == 0)
2431                         return -EINVAL;
2432
2433                 if (!nfs_verify_server_address(sap))
2434                         return -EINVAL;
2435
2436                 return nfs4_validate_text_mount_data(options, args, dev_name);
2437         }
2438
2439         return 0;
2440
2441 out_no_data:
2442         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2443         return -EINVAL;
2444
2445 out_inval_auth:
2446         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2447                  data->auth_flavourlen);
2448         return -EINVAL;
2449
2450 out_no_address:
2451         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2452         return -EINVAL;
2453 }
2454
2455 /*
2456  * Get the superblock for the NFS4 root partition
2457  */
2458 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
2459         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2460 {
2461         struct nfs_parsed_mount_data *data = raw_data;
2462         struct super_block *s;
2463         struct nfs_server *server;
2464         struct nfs_fh *mntfh;
2465         struct dentry *mntroot;
2466         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2467         struct nfs_sb_mountdata sb_mntdata = {
2468                 .mntflags = flags,
2469         };
2470         int error = -ENOMEM;
2471
2472         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2473         if (data == NULL || mntfh == NULL)
2474                 goto out_free_fh;
2475
2476         security_init_mnt_opts(&data->lsm_opts);
2477
2478         /* Get a volume representation */
2479         server = nfs4_create_server(data, mntfh);
2480         if (IS_ERR(server)) {
2481                 error = PTR_ERR(server);
2482                 goto out;
2483         }
2484         sb_mntdata.server = server;
2485
2486         if (server->flags & NFS4_MOUNT_UNSHARED)
2487                 compare_super = NULL;
2488
2489         /* Get a superblock - note that we may end up sharing one that already exists */
2490         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2491         if (IS_ERR(s)) {
2492                 error = PTR_ERR(s);
2493                 goto out_free;
2494         }
2495
2496         if (s->s_fs_info != server) {
2497                 nfs_free_server(server);
2498                 server = NULL;
2499         } else {
2500                 error = nfs_bdi_register(server);
2501                 if (error)
2502                         goto error_splat_super;
2503         }
2504
2505         if (!s->s_root) {
2506                 /* initial superblock/root creation */
2507                 nfs4_fill_super(s);
2508                 nfs_fscache_get_super_cookie(
2509                         s, data ? data->fscache_uniq : NULL, NULL);
2510         }
2511
2512         mntroot = nfs4_get_root(s, mntfh);
2513         if (IS_ERR(mntroot)) {
2514                 error = PTR_ERR(mntroot);
2515                 goto error_splat_super;
2516         }
2517
2518         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2519         if (error)
2520                 goto error_splat_root;
2521
2522         s->s_flags |= MS_ACTIVE;
2523         mnt->mnt_sb = s;
2524         mnt->mnt_root = mntroot;
2525         error = 0;
2526
2527 out:
2528         security_free_mnt_opts(&data->lsm_opts);
2529 out_free_fh:
2530         kfree(mntfh);
2531         return error;
2532
2533 out_free:
2534         nfs_free_server(server);
2535         goto out;
2536
2537 error_splat_root:
2538         dput(mntroot);
2539 error_splat_super:
2540         deactivate_locked_super(s);
2541         goto out;
2542 }
2543
2544 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2545                 int flags, void *data, const char *hostname)
2546 {
2547         struct vfsmount *root_mnt;
2548         char *root_devname;
2549         size_t len;
2550
2551         len = strlen(hostname) + 3;
2552         root_devname = kmalloc(len, GFP_KERNEL);
2553         if (root_devname == NULL)
2554                 return ERR_PTR(-ENOMEM);
2555         snprintf(root_devname, len, "%s:/", hostname);
2556         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2557         kfree(root_devname);
2558         return root_mnt;
2559 }
2560
2561 static void nfs_fix_devname(const struct path *path, struct vfsmount *mnt)
2562 {
2563         char *page = (char *) __get_free_page(GFP_KERNEL);
2564         char *devname, *tmp;
2565
2566         if (page == NULL)
2567                 return;
2568         devname = nfs_path(path->mnt->mnt_devname,
2569                         path->mnt->mnt_root, path->dentry,
2570                         page, PAGE_SIZE);
2571         if (devname == NULL)
2572                 goto out_freepage;
2573         tmp = kstrdup(devname, GFP_KERNEL);
2574         if (tmp == NULL)
2575                 goto out_freepage;
2576         kfree(mnt->mnt_devname);
2577         mnt->mnt_devname = tmp;
2578 out_freepage:
2579         free_page((unsigned long)page);
2580 }
2581
2582 static int nfs_follow_remote_path(struct vfsmount *root_mnt,
2583                 const char *export_path, struct vfsmount *mnt_target)
2584 {
2585         struct mnt_namespace *ns_private;
2586         struct nameidata nd;
2587         struct super_block *s;
2588         int ret;
2589
2590         ns_private = create_mnt_ns(root_mnt);
2591         ret = PTR_ERR(ns_private);
2592         if (IS_ERR(ns_private))
2593                 goto out_mntput;
2594
2595         ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
2596                         export_path, LOOKUP_FOLLOW, &nd);
2597
2598         put_mnt_ns(ns_private);
2599
2600         if (ret != 0)
2601                 goto out_err;
2602
2603         s = nd.path.mnt->mnt_sb;
2604         atomic_inc(&s->s_active);
2605         mnt_target->mnt_sb = s;
2606         mnt_target->mnt_root = dget(nd.path.dentry);
2607
2608         /* Correct the device pathname */
2609         nfs_fix_devname(&nd.path, mnt_target);
2610
2611         path_put(&nd.path);
2612         down_write(&s->s_umount);
2613         return 0;
2614 out_mntput:
2615         mntput(root_mnt);
2616 out_err:
2617         return ret;
2618 }
2619
2620 static int nfs4_try_mount(int flags, const char *dev_name,
2621                          struct nfs_parsed_mount_data *data,
2622                          struct vfsmount *mnt)
2623 {
2624         char *export_path;
2625         struct vfsmount *root_mnt;
2626         int error;
2627
2628         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2629
2630         export_path = data->nfs_server.export_path;
2631         data->nfs_server.export_path = "/";
2632         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2633                         data->nfs_server.hostname);
2634         data->nfs_server.export_path = export_path;
2635
2636         error = PTR_ERR(root_mnt);
2637         if (IS_ERR(root_mnt))
2638                 goto out;
2639
2640         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
2641
2642 out:
2643         dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n", error,
2644                         error != 0 ? " [error]" : "");
2645         return error;
2646 }
2647
2648 /*
2649  * Get the superblock for an NFS4 mountpoint
2650  */
2651 static int nfs4_get_sb(struct file_system_type *fs_type,
2652         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2653 {
2654         struct nfs_parsed_mount_data *data;
2655         int error = -ENOMEM;
2656
2657         data = nfs_alloc_parsed_mount_data(4);
2658         if (data == NULL)
2659                 goto out_free_data;
2660
2661         /* Validate the mount data */
2662         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2663         if (error < 0)
2664                 goto out;
2665
2666         error = nfs4_try_mount(flags, dev_name, data, mnt);
2667
2668 out:
2669         kfree(data->client_address);
2670         kfree(data->nfs_server.export_path);
2671         kfree(data->nfs_server.hostname);
2672         kfree(data->fscache_uniq);
2673 out_free_data:
2674         kfree(data);
2675         dprintk("<-- nfs4_get_sb() = %d%s\n", error,
2676                         error != 0 ? " [error]" : "");
2677         return error;
2678 }
2679
2680 static void nfs4_kill_super(struct super_block *sb)
2681 {
2682         struct nfs_server *server = NFS_SB(sb);
2683
2684         dprintk("--> %s\n", __func__);
2685         nfs_super_return_all_delegations(sb);
2686         kill_anon_super(sb);
2687         nfs_fscache_release_super_cookie(sb);
2688         nfs_free_server(server);
2689         dprintk("<-- %s\n", __func__);
2690 }
2691
2692 /*
2693  * Clone an NFS4 server record on xdev traversal (FSID-change)
2694  */
2695 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2696                             const char *dev_name, void *raw_data,
2697                             struct vfsmount *mnt)
2698 {
2699         struct nfs_clone_mount *data = raw_data;
2700         struct super_block *s;
2701         struct nfs_server *server;
2702         struct dentry *mntroot;
2703         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2704         struct nfs_sb_mountdata sb_mntdata = {
2705                 .mntflags = flags,
2706         };
2707         int error;
2708
2709         dprintk("--> nfs4_xdev_get_sb()\n");
2710
2711         /* create a new volume representation */
2712         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2713         if (IS_ERR(server)) {
2714                 error = PTR_ERR(server);
2715                 goto out_err_noserver;
2716         }
2717         sb_mntdata.server = server;
2718
2719         if (server->flags & NFS4_MOUNT_UNSHARED)
2720                 compare_super = NULL;
2721
2722         /* Get a superblock - note that we may end up sharing one that already exists */
2723         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2724         if (IS_ERR(s)) {
2725                 error = PTR_ERR(s);
2726                 goto out_err_nosb;
2727         }
2728
2729         if (s->s_fs_info != server) {
2730                 nfs_free_server(server);
2731                 server = NULL;
2732         } else {
2733                 error = nfs_bdi_register(server);
2734                 if (error)
2735                         goto error_splat_super;
2736         }
2737
2738         if (!s->s_root) {
2739                 /* initial superblock/root creation */
2740                 nfs4_clone_super(s, data->sb);
2741                 nfs_fscache_get_super_cookie(s, NULL, data);
2742         }
2743
2744         mntroot = nfs4_get_root(s, data->fh);
2745         if (IS_ERR(mntroot)) {
2746                 error = PTR_ERR(mntroot);
2747                 goto error_splat_super;
2748         }
2749         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2750                 dput(mntroot);
2751                 error = -ESTALE;
2752                 goto error_splat_super;
2753         }
2754
2755         s->s_flags |= MS_ACTIVE;
2756         mnt->mnt_sb = s;
2757         mnt->mnt_root = mntroot;
2758
2759         security_sb_clone_mnt_opts(data->sb, s);
2760
2761         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2762         return 0;
2763
2764 out_err_nosb:
2765         nfs_free_server(server);
2766 out_err_noserver:
2767         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2768         return error;
2769
2770 error_splat_super:
2771         deactivate_locked_super(s);
2772         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2773         return error;
2774 }
2775
2776 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
2777                 int flags, const char *dev_name, void *raw_data,
2778                 struct vfsmount *mnt)
2779 {
2780         struct nfs_clone_mount *data = raw_data;
2781         struct super_block *s;
2782         struct nfs_server *server;
2783         struct dentry *mntroot;
2784         struct nfs_fh mntfh;
2785         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2786         struct nfs_sb_mountdata sb_mntdata = {
2787                 .mntflags = flags,
2788         };
2789         int error;
2790
2791         dprintk("--> nfs4_referral_get_sb()\n");
2792
2793         /* create a new volume representation */
2794         server = nfs4_create_referral_server(data, &mntfh);
2795         if (IS_ERR(server)) {
2796                 error = PTR_ERR(server);
2797                 goto out_err_noserver;
2798         }
2799         sb_mntdata.server = server;
2800
2801         if (server->flags & NFS4_MOUNT_UNSHARED)
2802                 compare_super = NULL;
2803
2804         /* Get a superblock - note that we may end up sharing one that already exists */
2805         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2806         if (IS_ERR(s)) {
2807                 error = PTR_ERR(s);
2808                 goto out_err_nosb;
2809         }
2810
2811         if (s->s_fs_info != server) {
2812                 nfs_free_server(server);
2813                 server = NULL;
2814         } else {
2815                 error = nfs_bdi_register(server);
2816                 if (error)
2817                         goto error_splat_super;
2818         }
2819
2820         if (!s->s_root) {
2821                 /* initial superblock/root creation */
2822                 nfs4_fill_super(s);
2823                 nfs_fscache_get_super_cookie(s, NULL, data);
2824         }
2825
2826         mntroot = nfs4_get_root(s, &mntfh);
2827         if (IS_ERR(mntroot)) {
2828                 error = PTR_ERR(mntroot);
2829                 goto error_splat_super;
2830         }
2831         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2832                 dput(mntroot);
2833                 error = -ESTALE;
2834                 goto error_splat_super;
2835         }
2836
2837         s->s_flags |= MS_ACTIVE;
2838         mnt->mnt_sb = s;
2839         mnt->mnt_root = mntroot;
2840
2841         security_sb_clone_mnt_opts(data->sb, s);
2842
2843         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2844         return 0;
2845
2846 out_err_nosb:
2847         nfs_free_server(server);
2848 out_err_noserver:
2849         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2850         return error;
2851
2852 error_splat_super:
2853         deactivate_locked_super(s);
2854         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2855         return error;
2856 }
2857
2858 /*
2859  * Create an NFS4 server record on referral traversal
2860  */
2861 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
2862                 int flags, const char *dev_name, void *raw_data,
2863                 struct vfsmount *mnt)
2864 {
2865         struct nfs_clone_mount *data = raw_data;
2866         char *export_path;
2867         struct vfsmount *root_mnt;
2868         int error;
2869
2870         dprintk("--> nfs4_referral_get_sb()\n");
2871
2872         export_path = data->mnt_path;
2873         data->mnt_path = "/";
2874
2875         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
2876                         flags, data, data->hostname);
2877         data->mnt_path = export_path;
2878
2879         error = PTR_ERR(root_mnt);
2880         if (IS_ERR(root_mnt))
2881                 goto out;
2882
2883         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
2884 out:
2885         dprintk("<-- nfs4_referral_get_sb() = %d%s\n", error,
2886                         error != 0 ? " [error]" : "");
2887         return error;
2888 }
2889
2890 #endif /* CONFIG_NFS_V4 */