fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/smp_lock.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/mnt_namespace.h>
  46 #include <linux/namei.h>
  47 #include <linux/nfs_idmap.h>
  48 #include <linux/vfs.h>
  49 #include <linux/inet.h>
  50 #include <linux/in6.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56
  57 #include <asm/system.h>
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66
  67 #define NFSDBG_FACILITY         NFSDBG_VFS
  68
  69 enum {
  70         /* Mount options that take no arguments */
  71         Opt_soft, Opt_hard,
  72         Opt_posix, Opt_noposix,
  73         Opt_cto, Opt_nocto,
  74         Opt_ac, Opt_noac,
  75         Opt_lock, Opt_nolock,
  76         Opt_v2, Opt_v3,
  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_udp, "udp" },
 131         { Opt_tcp, "tcp" },
 132         { Opt_rdma, "rdma" },
 133         { Opt_acl, "acl" },
 134         { Opt_noacl, "noacl" },
 135         { Opt_rdirplus, "rdirplus" },
 136         { Opt_nordirplus, "nordirplus" },
 137         { Opt_sharecache, "sharecache" },
 138         { Opt_nosharecache, "nosharecache" },
 139         { Opt_resvport, "resvport" },
 140         { Opt_noresvport, "noresvport" },
 141         { Opt_fscache, "fsc" },
 142         { Opt_fscache_uniq, "fsc=%s" },
 143         { Opt_nofscache, "nofsc" },
 144
 145         { Opt_port, "port=%s" },
 146         { Opt_rsize, "rsize=%s" },
 147         { Opt_wsize, "wsize=%s" },
 148         { Opt_bsize, "bsize=%s" },
 149         { Opt_timeo, "timeo=%s" },
 150         { Opt_retrans, "retrans=%s" },
 151         { Opt_acregmin, "acregmin=%s" },
 152         { Opt_acregmax, "acregmax=%s" },
 153         { Opt_acdirmin, "acdirmin=%s" },
 154         { Opt_acdirmax, "acdirmax=%s" },
 155         { Opt_actimeo, "actimeo=%s" },
 156         { Opt_namelen, "namlen=%s" },
 157         { Opt_mountport, "mountport=%s" },
 158         { Opt_mountvers, "mountvers=%s" },
 159         { Opt_nfsvers, "nfsvers=%s" },
 160         { Opt_nfsvers, "vers=%s" },
 161         { Opt_minorversion, "minorversion=%u" },
 162
 163         { Opt_sec, "sec=%s" },
 164         { Opt_proto, "proto=%s" },
 165         { Opt_mountproto, "mountproto=%s" },
 166         { Opt_addr, "addr=%s" },
 167         { Opt_clientaddr, "clientaddr=%s" },
 168         { Opt_mounthost, "mounthost=%s" },
 169         { Opt_mountaddr, "mountaddr=%s" },
 170
 171         { Opt_lookupcache, "lookupcache=%s" },
 172
 173         { Opt_err, NULL }
 174 };
 175
 176 enum {
 177         Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
 178
 179         Opt_xprt_err
 180 };
 181
 182 static const match_table_t nfs_xprt_protocol_tokens = {
 183         { Opt_xprt_udp, "udp" },
 184         { Opt_xprt_tcp, "tcp" },
 185         { Opt_xprt_rdma, "rdma" },
 186
 187         { Opt_xprt_err, NULL }
 188 };
 189
 190 enum {
 191         Opt_sec_none, Opt_sec_sys,
 192         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 193         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 194         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 195
 196         Opt_sec_err
 197 };
 198
 199 static const match_table_t nfs_secflavor_tokens = {
 200         { Opt_sec_none, "none" },
 201         { Opt_sec_none, "null" },
 202         { Opt_sec_sys, "sys" },
 203
 204         { Opt_sec_krb5, "krb5" },
 205         { Opt_sec_krb5i, "krb5i" },
 206         { Opt_sec_krb5p, "krb5p" },
 207
 208         { Opt_sec_lkey, "lkey" },
 209         { Opt_sec_lkeyi, "lkeyi" },
 210         { Opt_sec_lkeyp, "lkeyp" },
 211
 212         { Opt_sec_spkm, "spkm3" },
 213         { Opt_sec_spkmi, "spkm3i" },
 214         { Opt_sec_spkmp, "spkm3p" },
 215
 216         { Opt_sec_err, NULL }
 217 };
 218
 219 enum {
 220         Opt_lookupcache_all, Opt_lookupcache_positive,
 221         Opt_lookupcache_none,
 222
 223         Opt_lookupcache_err
 224 };
 225
 226 static match_table_t nfs_lookupcache_tokens = {
 227         { Opt_lookupcache_all, "all" },
 228         { Opt_lookupcache_positive, "pos" },
 229         { Opt_lookupcache_positive, "positive" },
 230         { Opt_lookupcache_none, "none" },
 231
 232         { Opt_lookupcache_err, NULL }
 233 };
 234
 235
 236 static void nfs_umount_begin(struct super_block *);
 237 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 238 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 239 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 240 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 241 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 242                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 243 static void nfs_kill_super(struct super_block *);
 244 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 245
 246 static struct file_system_type nfs_fs_type = {
 247         .owner          = THIS_MODULE,
 248         .name           = "nfs",
 249         .get_sb         = nfs_get_sb,
 250         .kill_sb        = nfs_kill_super,
 251         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 252 };
 253
 254 struct file_system_type nfs_xdev_fs_type = {
 255         .owner          = THIS_MODULE,
 256         .name           = "nfs",
 257         .get_sb         = nfs_xdev_get_sb,
 258         .kill_sb        = nfs_kill_super,
 259         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 260 };
 261
 262 static const struct super_operations nfs_sops = {
 263         .alloc_inode    = nfs_alloc_inode,
 264         .destroy_inode  = nfs_destroy_inode,
 265         .write_inode    = nfs_write_inode,
 266         .statfs         = nfs_statfs,
 267         .clear_inode    = nfs_clear_inode,
 268         .umount_begin   = nfs_umount_begin,
 269         .show_options   = nfs_show_options,
 270         .show_stats     = nfs_show_stats,
 271         .remount_fs     = nfs_remount,
 272 };
 273
 274 #ifdef CONFIG_NFS_V4
 275 static int nfs4_get_sb(struct file_system_type *fs_type,
 276         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 277 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
 278         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 279 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 280         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 281 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 282         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 283 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
 284         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 285 static void nfs4_kill_super(struct super_block *sb);
 286
 287 static struct file_system_type nfs4_fs_type = {
 288         .owner          = THIS_MODULE,
 289         .name           = "nfs4",
 290         .get_sb         = nfs4_get_sb,
 291         .kill_sb        = nfs4_kill_super,
 292         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 293 };
 294
 295 static struct file_system_type nfs4_remote_fs_type = {
 296         .owner          = THIS_MODULE,
 297         .name           = "nfs4",
 298         .get_sb         = nfs4_remote_get_sb,
 299         .kill_sb        = nfs4_kill_super,
 300         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 301 };
 302
 303 struct file_system_type nfs4_xdev_fs_type = {
 304         .owner          = THIS_MODULE,
 305         .name           = "nfs4",
 306         .get_sb         = nfs4_xdev_get_sb,
 307         .kill_sb        = nfs4_kill_super,
 308         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 309 };
 310
 311 static struct file_system_type nfs4_remote_referral_fs_type = {
 312         .owner          = THIS_MODULE,
 313         .name           = "nfs4",
 314         .get_sb         = nfs4_remote_referral_get_sb,
 315         .kill_sb        = nfs4_kill_super,
 316         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 317 };
 318
 319 struct file_system_type nfs4_referral_fs_type = {
 320         .owner          = THIS_MODULE,
 321         .name           = "nfs4",
 322         .get_sb         = nfs4_referral_get_sb,
 323         .kill_sb        = nfs4_kill_super,
 324         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 325 };
 326
 327 static const struct super_operations nfs4_sops = {
 328         .alloc_inode    = nfs_alloc_inode,
 329         .destroy_inode  = nfs_destroy_inode,
 330         .write_inode    = nfs_write_inode,
 331         .statfs         = nfs_statfs,
 332         .clear_inode    = nfs4_clear_inode,
 333         .umount_begin   = nfs_umount_begin,
 334         .show_options   = nfs_show_options,
 335         .show_stats     = nfs_show_stats,
 336         .remount_fs     = nfs_remount,
 337 };
 338 #endif
 339
 340 static struct shrinker acl_shrinker = {
 341         .shrink         = nfs_access_cache_shrinker,
 342         .seeks          = DEFAULT_SEEKS,
 343 };
 344
 345 /*
 346  * Register the NFS filesystems
 347  */
 348 int __init register_nfs_fs(void)
 349 {
 350         int ret;
 351
 352         ret = register_filesystem(&nfs_fs_type);
 353         if (ret < 0)
 354                 goto error_0;
 355
 356         ret = nfs_register_sysctl();
 357         if (ret < 0)
 358                 goto error_1;
 359 #ifdef CONFIG_NFS_V4
 360         ret = register_filesystem(&nfs4_fs_type);
 361         if (ret < 0)
 362                 goto error_2;
 363 #endif
 364         register_shrinker(&acl_shrinker);
 365         return 0;
 366
 367 #ifdef CONFIG_NFS_V4
 368 error_2:
 369         nfs_unregister_sysctl();
 370 #endif
 371 error_1:
 372         unregister_filesystem(&nfs_fs_type);
 373 error_0:
 374         return ret;
 375 }
 376
 377 /*
 378  * Unregister the NFS filesystems
 379  */
 380 void __exit unregister_nfs_fs(void)
 381 {
 382         unregister_shrinker(&acl_shrinker);
 383 #ifdef CONFIG_NFS_V4
 384         unregister_filesystem(&nfs4_fs_type);
 385 #endif
 386         nfs_unregister_sysctl();
 387         unregister_filesystem(&nfs_fs_type);
 388 }
 389
 390 void nfs_sb_active(struct super_block *sb)
 391 {
 392         struct nfs_server *server = NFS_SB(sb);
 393
 394         if (atomic_inc_return(&server->active) == 1)
 395                 atomic_inc(&sb->s_active);
 396 }
 397
 398 void nfs_sb_deactive(struct super_block *sb)
 399 {
 400         struct nfs_server *server = NFS_SB(sb);
 401
 402         if (atomic_dec_and_test(&server->active))
 403                 deactivate_super(sb);
 404 }
 405
 406 /*
 407  * Deliver file system statistics to userspace
 408  */
 409 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 410 {
 411         struct nfs_server *server = NFS_SB(dentry->d_sb);
 412         unsigned char blockbits;
 413         unsigned long blockres;
 414         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 415         struct nfs_fattr fattr;
 416         struct nfs_fsstat res = {
 417                         .fattr = &fattr,
 418         };
 419         int error;
 420
 421         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 422         if (error < 0)
 423                 goto out_err;
 424         buf->f_type = NFS_SUPER_MAGIC;
 425
 426         /*
 427          * Current versions of glibc do not correctly handle the
 428          * case where f_frsize != f_bsize.  Eventually we want to
 429          * report the value of wtmult in this field.
 430          */
 431         buf->f_frsize = dentry->d_sb->s_blocksize;
 432
 433         /*
 434          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 435          * are reported in units of f_frsize.  Linux hasn't had
 436          * an f_frsize field in its statfs struct until recently,
 437          * thus historically Linux's sys_statfs reports these
 438          * fields in units of f_bsize.
 439          */
 440         buf->f_bsize = dentry->d_sb->s_blocksize;
 441         blockbits = dentry->d_sb->s_blocksize_bits;
 442         blockres = (1 << blockbits) - 1;
 443         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 444         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 445         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 446
 447         buf->f_files = res.tfiles;
 448         buf->f_ffree = res.afiles;
 449
 450         buf->f_namelen = server->namelen;
 451
 452         return 0;
 453
 454  out_err:
 455         dprintk("%s: statfs error = %d\n", __func__, -error);
 456         return error;
 457 }
 458
 459 /*
 460  * Map the security flavour number to a name
 461  */
 462 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 463 {
 464         static const struct {
 465                 rpc_authflavor_t flavour;
 466                 const char *str;
 467         } sec_flavours[] = {
 468                 { RPC_AUTH_NULL, "null" },
 469                 { RPC_AUTH_UNIX, "sys" },
 470                 { RPC_AUTH_GSS_KRB5, "krb5" },
 471                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 472                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 473                 { RPC_AUTH_GSS_LKEY, "lkey" },
 474                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 475                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 476                 { RPC_AUTH_GSS_SPKM, "spkm" },
 477                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 478                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 479                 { UINT_MAX, "unknown" }
 480         };
 481         int i;
 482
 483         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 484                 if (sec_flavours[i].flavour == flavour)
 485                         break;
 486         }
 487         return sec_flavours[i].str;
 488 }
 489
 490 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 491                                     int showdefaults)
 492 {
 493         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 494
 495         switch (sap->sa_family) {
 496         case AF_INET: {
 497                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 498                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 499                 break;
 500         }
 501         case AF_INET6: {
 502                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 503                 seq_printf(m, ",mountaddr=%pI6", &sin6->sin6_addr);
 504                 break;
 505         }
 506         default:
 507                 if (showdefaults)
 508                         seq_printf(m, ",mountaddr=unspecified");
 509         }
 510
 511         if (nfss->mountd_version || showdefaults)
 512                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 513         if (nfss->mountd_port || showdefaults)
 514                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 515
 516         switch (nfss->mountd_protocol) {
 517         case IPPROTO_UDP:
 518                 seq_printf(m, ",mountproto=udp");
 519                 break;
 520         case IPPROTO_TCP:
 521                 seq_printf(m, ",mountproto=tcp");
 522                 break;
 523         default:
 524                 if (showdefaults)
 525                         seq_printf(m, ",mountproto=auto");
 526         }
 527 }
 528
 529 /*
 530  * Describe the mount options in force on this server representation
 531  */
 532 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 533                                    int showdefaults)
 534 {
 535         static const struct proc_nfs_info {
 536                 int flag;
 537                 const char *str;
 538                 const char *nostr;
 539         } nfs_info[] = {
 540                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 541                 { NFS_MOUNT_POSIX, ",posix", "" },
 542                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 543                 { NFS_MOUNT_NOAC, ",noac", "" },
 544                 { NFS_MOUNT_NONLM, ",nolock", "" },
 545                 { NFS_MOUNT_NOACL, ",noacl", "" },
 546                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 547                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 548                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 549                 { 0, NULL, NULL }
 550         };
 551         const struct proc_nfs_info *nfs_infop;
 552         struct nfs_client *clp = nfss->nfs_client;
 553         u32 version = clp->rpc_ops->version;
 554
 555         seq_printf(m, ",vers=%u", version);
 556         seq_printf(m, ",rsize=%u", nfss->rsize);
 557         seq_printf(m, ",wsize=%u", nfss->wsize);
 558         if (nfss->bsize != 0)
 559                 seq_printf(m, ",bsize=%u", nfss->bsize);
 560         seq_printf(m, ",namlen=%u", nfss->namelen);
 561         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 562                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 563         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 564                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 565         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 566                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 567         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 568                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 569         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 570                 if (nfss->flags & nfs_infop->flag)
 571                         seq_puts(m, nfs_infop->str);
 572                 else
 573                         seq_puts(m, nfs_infop->nostr);
 574         }
 575         seq_printf(m, ",proto=%s",
 576                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 577         if (version == 4) {
 578                 if (nfss->port != NFS_PORT)
 579                         seq_printf(m, ",port=%u", nfss->port);
 580         } else
 581                 if (nfss->port)
 582                         seq_printf(m, ",port=%u", nfss->port);
 583
 584         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 585         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 586         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 587
 588         if (version != 4)
 589                 nfs_show_mountd_options(m, nfss, showdefaults);
 590
 591 #ifdef CONFIG_NFS_V4
 592         if (clp->rpc_ops->version == 4)
 593                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 594 #endif
 595         if (nfss->options & NFS_OPTION_FSCACHE)
 596                 seq_printf(m, ",fsc");
 597 }
 598
 599 /*
 600  * Describe the mount options on this VFS mountpoint
 601  */
 602 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 603 {
 604         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 605
 606         nfs_show_mount_options(m, nfss, 0);
 607
 608         seq_printf(m, ",addr=%s",
 609                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 610                                                         RPC_DISPLAY_ADDR));
 611
 612         return 0;
 613 }
 614
 615 /*
 616  * Present statistical information for this VFS mountpoint
 617  */
 618 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 619 {
 620         int i, cpu;
 621         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 622         struct rpc_auth *auth = nfss->client->cl_auth;
 623         struct nfs_iostats totals = { };
 624
 625         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 626
 627         /*
 628          * Display all mount option settings
 629          */
 630         seq_printf(m, "\n\topts:\t");
 631         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 632         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 633         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 634         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 635         nfs_show_mount_options(m, nfss, 1);
 636
 637         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 638
 639         seq_printf(m, "\n\tcaps:\t");
 640         seq_printf(m, "caps=0x%x", nfss->caps);
 641         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 642         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 643         seq_printf(m, ",bsize=%u", nfss->bsize);
 644         seq_printf(m, ",namlen=%u", nfss->namelen);
 645
 646 #ifdef CONFIG_NFS_V4
 647         if (nfss->nfs_client->rpc_ops->version == 4) {
 648                 seq_printf(m, "\n\tnfsv4:\t");
 649                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 650                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 651                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 652         }
 653 #endif
 654
 655         /*
 656          * Display security flavor in effect for this mount
 657          */
 658         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 659         if (auth->au_flavor)
 660                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 661
 662         /*
 663          * Display superblock I/O counters
 664          */
 665         for_each_possible_cpu(cpu) {
 666                 struct nfs_iostats *stats;
 667
 668                 preempt_disable();
 669                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 670
 671                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 672                         totals.events[i] += stats->events[i];
 673                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 674                         totals.bytes[i] += stats->bytes[i];
 675 #ifdef CONFIG_NFS_FSCACHE
 676                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 677                         totals.fscache[i] += stats->fscache[i];
 678 #endif
 679
 680                 preempt_enable();
 681         }
 682
 683         seq_printf(m, "\n\tevents:\t");
 684         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 685                 seq_printf(m, "%lu ", totals.events[i]);
 686         seq_printf(m, "\n\tbytes:\t");
 687         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 688                 seq_printf(m, "%Lu ", totals.bytes[i]);
 689 #ifdef CONFIG_NFS_FSCACHE
 690         if (nfss->options & NFS_OPTION_FSCACHE) {
 691                 seq_printf(m, "\n\tfsc:\t");
 692                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 693                         seq_printf(m, "%Lu ", totals.bytes[i]);
 694         }
 695 #endif
 696         seq_printf(m, "\n");
 697
 698         rpc_print_iostats(m, nfss->client);
 699
 700         return 0;
 701 }
 702
 703 /*
 704  * Begin unmount by attempting to remove all automounted mountpoints we added
 705  * in response to xdev traversals and referrals
 706  */
 707 static void nfs_umount_begin(struct super_block *sb)
 708 {
 709         struct nfs_server *server;
 710         struct rpc_clnt *rpc;
 711
 712         lock_kernel();
 713
 714         server = NFS_SB(sb);
 715         /* -EIO all pending I/O */
 716         rpc = server->client_acl;
 717         if (!IS_ERR(rpc))
 718                 rpc_killall_tasks(rpc);
 719         rpc = server->client;
 720         if (!IS_ERR(rpc))
 721                 rpc_killall_tasks(rpc);
 722
 723         unlock_kernel();
 724 }
 725
 726 /*
 727  * Sanity-check a server address provided by the mount command.
 728  *
 729  * Address family must be initialized, and address must not be
 730  * the ANY address for that family.
 731  */
 732 static int nfs_verify_server_address(struct sockaddr *addr)
 733 {
 734         switch (addr->sa_family) {
 735         case AF_INET: {
 736                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 737                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 738         }
 739         case AF_INET6: {
 740                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 741                 return !ipv6_addr_any(sa);
 742         }
 743         }
 744
 745         return 0;
 746 }
 747
 748 static void nfs_parse_ipv4_address(char *string, size_t str_len,
 749                                    struct sockaddr *sap, size_t *addr_len)
 750 {
 751         struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 752         u8 *addr = (u8 *)&sin->sin_addr.s_addr;
 753
 754         if (str_len <= INET_ADDRSTRLEN) {
 755                 dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
 756                                 (int)str_len, string);
 757
 758                 sin->sin_family = AF_INET;
 759                 *addr_len = sizeof(*sin);
 760                 if (in4_pton(string, str_len, addr, '\0', NULL))
 761                         return;
 762         }
 763
 764         sap->sa_family = AF_UNSPEC;
 765         *addr_len = 0;
 766 }
 767
 768 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 769 static int nfs_parse_ipv6_scope_id(const char *string, const size_t str_len,
 770                                    const char *delim,
 771                                    struct sockaddr_in6 *sin6)
 772 {
 773         char *p;
 774         size_t len;
 775
 776         if ((string + str_len) == delim)
 777                 return 1;
 778
 779         if (*delim != IPV6_SCOPE_DELIMITER)
 780                 return 0;
 781
 782         if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
 783                 return 0;
 784
 785         len = (string + str_len) - delim - 1;
 786         p = kstrndup(delim + 1, len, GFP_KERNEL);
 787         if (p) {
 788                 unsigned long scope_id = 0;
 789                 struct net_device *dev;
 790
 791                 dev = dev_get_by_name(&init_net, p);
 792                 if (dev != NULL) {
 793                         scope_id = dev->ifindex;
 794                         dev_put(dev);
 795                 } else {
 796                         if (strict_strtoul(p, 10, &scope_id) == 0) {
 797                                 kfree(p);
 798                                 return 0;
 799                         }
 800                 }
 801
 802                 kfree(p);
 803
 804                 sin6->sin6_scope_id = scope_id;
 805                 dfprintk(MOUNT, "NFS: IPv6 scope ID = %lu\n", scope_id);
 806                 return 1;
 807         }
 808
 809         return 0;
 810 }
 811
 812 static void nfs_parse_ipv6_address(char *string, size_t str_len,
 813                                    struct sockaddr *sap, size_t *addr_len)
 814 {
 815         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 816         u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
 817         const char *delim;
 818
 819         if (str_len <= INET6_ADDRSTRLEN) {
 820                 dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
 821                                 (int)str_len, string);
 822
 823                 sin6->sin6_family = AF_INET6;
 824                 *addr_len = sizeof(*sin6);
 825                 if (in6_pton(string, str_len, addr,
 826                                         IPV6_SCOPE_DELIMITER, &delim) != 0) {
 827                         if (nfs_parse_ipv6_scope_id(string, str_len,
 828                                                         delim, sin6) != 0)
 829                                 return;
 830                 }
 831         }
 832
 833         sap->sa_family = AF_UNSPEC;
 834         *addr_len = 0;
 835 }
 836 #else
 837 static void nfs_parse_ipv6_address(char *string, size_t str_len,
 838                                    struct sockaddr *sap, size_t *addr_len)
 839 {
 840         sap->sa_family = AF_UNSPEC;
 841         *addr_len = 0;
 842 }
 843 #endif
 844
 845 /*
 846  * Construct a sockaddr based on the contents of a string that contains
 847  * an IP address in presentation format.
 848  *
 849  * If there is a problem constructing the new sockaddr, set the address
 850  * family to AF_UNSPEC.
 851  */
 852 void nfs_parse_ip_address(char *string, size_t str_len,
 853                                  struct sockaddr *sap, size_t *addr_len)
 854 {
 855         unsigned int i, colons;
 856
 857         colons = 0;
 858         for (i = 0; i < str_len; i++)
 859                 if (string[i] == ':')
 860                         colons++;
 861
 862         if (colons >= 2)
 863                 nfs_parse_ipv6_address(string, str_len, sap, addr_len);
 864         else
 865                 nfs_parse_ipv4_address(string, str_len, sap, addr_len);
 866 }
 867
 868 /*
 869  * Sanity check the NFS transport protocol.
 870  *
 871  */
 872 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 873 {
 874         switch (mnt->nfs_server.protocol) {
 875         case XPRT_TRANSPORT_UDP:
 876         case XPRT_TRANSPORT_TCP:
 877         case XPRT_TRANSPORT_RDMA:
 878                 break;
 879         default:
 880                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 881         }
 882 }
 883
 884 /*
 885  * For text based NFSv2/v3 mounts, the mount protocol transport default
 886  * settings should depend upon the specified NFS transport.
 887  */
 888 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 889 {
 890         nfs_validate_transport_protocol(mnt);
 891
 892         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 893             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 894                         return;
 895         switch (mnt->nfs_server.protocol) {
 896         case XPRT_TRANSPORT_UDP:
 897                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 898                 break;
 899         case XPRT_TRANSPORT_TCP:
 900         case XPRT_TRANSPORT_RDMA:
 901                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 902         }
 903 }
 904
 905 /*
 906  * Parse the value of the 'sec=' option.
 907  *
 908  * The flavor_len setting is for v4 mounts.
 909  */
 910 static int nfs_parse_security_flavors(char *value,
 911                                       struct nfs_parsed_mount_data *mnt)
 912 {
 913         substring_t args[MAX_OPT_ARGS];
 914
 915         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 916
 917         switch (match_token(value, nfs_secflavor_tokens, args)) {
 918         case Opt_sec_none:
 919                 mnt->auth_flavor_len = 0;
 920                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 921                 break;
 922         case Opt_sec_sys:
 923                 mnt->auth_flavor_len = 0;
 924                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 925                 break;
 926         case Opt_sec_krb5:
 927                 mnt->auth_flavor_len = 1;
 928                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 929                 break;
 930         case Opt_sec_krb5i:
 931                 mnt->auth_flavor_len = 1;
 932                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 933                 break;
 934         case Opt_sec_krb5p:
 935                 mnt->auth_flavor_len = 1;
 936                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 937                 break;
 938         case Opt_sec_lkey:
 939                 mnt->auth_flavor_len = 1;
 940                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 941                 break;
 942         case Opt_sec_lkeyi:
 943                 mnt->auth_flavor_len = 1;
 944                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 945                 break;
 946         case Opt_sec_lkeyp:
 947                 mnt->auth_flavor_len = 1;
 948                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 949                 break;
 950         case Opt_sec_spkm:
 951                 mnt->auth_flavor_len = 1;
 952                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
 953                 break;
 954         case Opt_sec_spkmi:
 955                 mnt->auth_flavor_len = 1;
 956                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
 957                 break;
 958         case Opt_sec_spkmp:
 959                 mnt->auth_flavor_len = 1;
 960                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
 961                 break;
 962         default:
 963                 return 0;
 964         }
 965
 966         return 1;
 967 }
 968
 969 /*
 970  * Error-check and convert a string of mount options from user space into
 971  * a data structure.  The whole mount string is processed; bad options are
 972  * skipped as they are encountered.  If there were no errors, return 1;
 973  * otherwise return 0 (zero).
 974  */
 975 static int nfs_parse_mount_options(char *raw,
 976                                    struct nfs_parsed_mount_data *mnt)
 977 {
 978         char *p, *string, *secdata;
 979         int rc, sloppy = 0, invalid_option = 0;
 980
 981         if (!raw) {
 982                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 983                 return 1;
 984         }
 985         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 986
 987         secdata = alloc_secdata();
 988         if (!secdata)
 989                 goto out_nomem;
 990
 991         rc = security_sb_copy_data(raw, secdata);
 992         if (rc)
 993                 goto out_security_failure;
 994
 995         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 996         if (rc)
 997                 goto out_security_failure;
 998
 999         free_secdata(secdata);
1000
1001         while ((p = strsep(&raw, ",")) != NULL) {
1002                 substring_t args[MAX_OPT_ARGS];
1003                 unsigned long option;
1004                 int int_option;
1005                 int token;
1006
1007                 if (!*p)
1008                         continue;
1009
1010                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1011
1012                 token = match_token(p, nfs_mount_option_tokens, args);
1013                 switch (token) {
1014
1015                 /*
1016                  * boolean options:  foo/nofoo
1017                  */
1018                 case Opt_soft:
1019                         mnt->flags |= NFS_MOUNT_SOFT;
1020                         break;
1021                 case Opt_hard:
1022                         mnt->flags &= ~NFS_MOUNT_SOFT;
1023                         break;
1024                 case Opt_posix:
1025                         mnt->flags |= NFS_MOUNT_POSIX;
1026                         break;
1027                 case Opt_noposix:
1028                         mnt->flags &= ~NFS_MOUNT_POSIX;
1029                         break;
1030                 case Opt_cto:
1031                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1032                         break;
1033                 case Opt_nocto:
1034                         mnt->flags |= NFS_MOUNT_NOCTO;
1035                         break;
1036                 case Opt_ac:
1037                         mnt->flags &= ~NFS_MOUNT_NOAC;
1038                         break;
1039                 case Opt_noac:
1040                         mnt->flags |= NFS_MOUNT_NOAC;
1041                         break;
1042                 case Opt_lock:
1043                         mnt->flags &= ~NFS_MOUNT_NONLM;
1044                         break;
1045                 case Opt_nolock:
1046                         mnt->flags |= NFS_MOUNT_NONLM;
1047                         break;
1048                 case Opt_v2:
1049                         mnt->flags &= ~NFS_MOUNT_VER3;
1050                         break;
1051                 case Opt_v3:
1052                         mnt->flags |= NFS_MOUNT_VER3;
1053                         break;
1054                 case Opt_udp:
1055                         mnt->flags &= ~NFS_MOUNT_TCP;
1056                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1057                         break;
1058                 case Opt_tcp:
1059                         mnt->flags |= NFS_MOUNT_TCP;
1060                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1061                         break;
1062                 case Opt_rdma:
1063                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1064                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1065                         xprt_load_transport(p);
1066                         break;
1067                 case Opt_acl:
1068                         mnt->flags &= ~NFS_MOUNT_NOACL;
1069                         break;
1070                 case Opt_noacl:
1071                         mnt->flags |= NFS_MOUNT_NOACL;
1072                         break;
1073                 case Opt_rdirplus:
1074                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1075                         break;
1076                 case Opt_nordirplus:
1077                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1078                         break;
1079                 case Opt_sharecache:
1080                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1081                         break;
1082                 case Opt_nosharecache:
1083                         mnt->flags |= NFS_MOUNT_UNSHARED;
1084                         break;
1085                 case Opt_resvport:
1086                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1087                         break;
1088                 case Opt_noresvport:
1089                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1090                         break;
1091                 case Opt_fscache:
1092                         mnt->options |= NFS_OPTION_FSCACHE;
1093                         kfree(mnt->fscache_uniq);
1094                         mnt->fscache_uniq = NULL;
1095                         break;
1096                 case Opt_nofscache:
1097                         mnt->options &= ~NFS_OPTION_FSCACHE;
1098                         kfree(mnt->fscache_uniq);
1099                         mnt->fscache_uniq = NULL;
1100                         break;
1101                 case Opt_fscache_uniq:
1102                         string = match_strdup(args);
1103                         if (!string)
1104                                 goto out_nomem;
1105                         kfree(mnt->fscache_uniq);
1106                         mnt->fscache_uniq = string;
1107                         mnt->options |= NFS_OPTION_FSCACHE;
1108                         break;
1109
1110                 /*
1111                  * options that take numeric values
1112                  */
1113                 case Opt_port:
1114                         string = match_strdup(args);
1115                         if (string == NULL)
1116                                 goto out_nomem;
1117                         rc = strict_strtoul(string, 10, &option);
1118                         kfree(string);
1119                         if (rc != 0 || option > USHORT_MAX)
1120                                 goto out_invalid_value;
1121                         mnt->nfs_server.port = option;
1122                         break;
1123                 case Opt_rsize:
1124                         string = match_strdup(args);
1125                         if (string == NULL)
1126                                 goto out_nomem;
1127                         rc = strict_strtoul(string, 10, &option);
1128                         kfree(string);
1129                         if (rc != 0)
1130                                 goto out_invalid_value;
1131                         mnt->rsize = option;
1132                         break;
1133                 case Opt_wsize:
1134                         string = match_strdup(args);
1135                         if (string == NULL)
1136                                 goto out_nomem;
1137                         rc = strict_strtoul(string, 10, &option);
1138                         kfree(string);
1139                         if (rc != 0)
1140                                 goto out_invalid_value;
1141                         mnt->wsize = option;
1142                         break;
1143                 case Opt_bsize:
1144                         string = match_strdup(args);
1145                         if (string == NULL)
1146                                 goto out_nomem;
1147                         rc = strict_strtoul(string, 10, &option);
1148                         kfree(string);
1149                         if (rc != 0)
1150                                 goto out_invalid_value;
1151                         mnt->bsize = option;
1152                         break;
1153                 case Opt_timeo:
1154                         string = match_strdup(args);
1155                         if (string == NULL)
1156                                 goto out_nomem;
1157                         rc = strict_strtoul(string, 10, &option);
1158                         kfree(string);
1159                         if (rc != 0 || option == 0)
1160                                 goto out_invalid_value;
1161                         mnt->timeo = option;
1162                         break;
1163                 case Opt_retrans:
1164                         string = match_strdup(args);
1165                         if (string == NULL)
1166                                 goto out_nomem;
1167                         rc = strict_strtoul(string, 10, &option);
1168                         kfree(string);
1169                         if (rc != 0 || option == 0)
1170                                 goto out_invalid_value;
1171                         mnt->retrans = option;
1172                         break;
1173                 case Opt_acregmin:
1174                         string = match_strdup(args);
1175                         if (string == NULL)
1176                                 goto out_nomem;
1177                         rc = strict_strtoul(string, 10, &option);
1178                         kfree(string);
1179                         if (rc != 0)
1180                                 goto out_invalid_value;
1181                         mnt->acregmin = option;
1182                         break;
1183                 case Opt_acregmax:
1184                         string = match_strdup(args);
1185                         if (string == NULL)
1186                                 goto out_nomem;
1187                         rc = strict_strtoul(string, 10, &option);
1188                         kfree(string);
1189                         if (rc != 0)
1190                                 goto out_invalid_value;
1191                         mnt->acregmax = option;
1192                         break;
1193                 case Opt_acdirmin:
1194                         string = match_strdup(args);
1195                         if (string == NULL)
1196                                 goto out_nomem;
1197                         rc = strict_strtoul(string, 10, &option);
1198                         kfree(string);
1199                         if (rc != 0)
1200                                 goto out_invalid_value;
1201                         mnt->acdirmin = option;
1202                         break;
1203                 case Opt_acdirmax:
1204                         string = match_strdup(args);
1205                         if (string == NULL)
1206                                 goto out_nomem;
1207                         rc = strict_strtoul(string, 10, &option);
1208                         kfree(string);
1209                         if (rc != 0)
1210                                 goto out_invalid_value;
1211                         mnt->acdirmax = option;
1212                         break;
1213                 case Opt_actimeo:
1214                         string = match_strdup(args);
1215                         if (string == NULL)
1216                                 goto out_nomem;
1217                         rc = strict_strtoul(string, 10, &option);
1218                         kfree(string);
1219                         if (rc != 0)
1220                                 goto out_invalid_value;
1221                         mnt->acregmin = mnt->acregmax =
1222                         mnt->acdirmin = mnt->acdirmax = option;
1223                         break;
1224                 case Opt_namelen:
1225                         string = match_strdup(args);
1226                         if (string == NULL)
1227                                 goto out_nomem;
1228                         rc = strict_strtoul(string, 10, &option);
1229                         kfree(string);
1230                         if (rc != 0)
1231                                 goto out_invalid_value;
1232                         mnt->namlen = option;
1233                         break;
1234                 case Opt_mountport:
1235                         string = match_strdup(args);
1236                         if (string == NULL)
1237                                 goto out_nomem;
1238                         rc = strict_strtoul(string, 10, &option);
1239                         kfree(string);
1240                         if (rc != 0 || option > USHORT_MAX)
1241                                 goto out_invalid_value;
1242                         mnt->mount_server.port = option;
1243                         break;
1244                 case Opt_mountvers:
1245                         string = match_strdup(args);
1246                         if (string == NULL)
1247                                 goto out_nomem;
1248                         rc = strict_strtoul(string, 10, &option);
1249                         kfree(string);
1250                         if (rc != 0 ||
1251                             option < NFS_MNT_VERSION ||
1252                             option > NFS_MNT3_VERSION)
1253                                 goto out_invalid_value;
1254                         mnt->mount_server.version = option;
1255                         break;
1256                 case Opt_nfsvers:
1257                         string = match_strdup(args);
1258                         if (string == NULL)
1259                                 goto out_nomem;
1260                         rc = strict_strtoul(string, 10, &option);
1261                         kfree(string);
1262                         if (rc != 0)
1263                                 goto out_invalid_value;
1264                         switch (option) {
1265                         case NFS2_VERSION:
1266                                 mnt->flags &= ~NFS_MOUNT_VER3;
1267                                 break;
1268                         case NFS3_VERSION:
1269                                 mnt->flags |= NFS_MOUNT_VER3;
1270                                 break;
1271                         default:
1272                                 goto out_invalid_value;
1273                         }
1274                         break;
1275                 case Opt_minorversion:
1276                         if (match_int(args, &int_option))
1277                                 return 0;
1278                         if (int_option < 0 || int_option > NFS4_MAX_MINOR_VERSION)
1279                                 return 0;
1280                         mnt->minorversion = int_option;
1281                         break;
1282
1283                 /*
1284                  * options that take text values
1285                  */
1286                 case Opt_sec:
1287                         string = match_strdup(args);
1288                         if (string == NULL)
1289                                 goto out_nomem;
1290                         rc = nfs_parse_security_flavors(string, mnt);
1291                         kfree(string);
1292                         if (!rc) {
1293                                 dfprintk(MOUNT, "NFS:   unrecognized "
1294                                                 "security flavor\n");
1295                                 return 0;
1296                         }
1297                         break;
1298                 case Opt_proto:
1299                         string = match_strdup(args);
1300                         if (string == NULL)
1301                                 goto out_nomem;
1302                         token = match_token(string,
1303                                             nfs_xprt_protocol_tokens, args);
1304
1305                         switch (token) {
1306                         case Opt_xprt_udp:
1307                                 mnt->flags &= ~NFS_MOUNT_TCP;
1308                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1309                                 kfree(string);
1310                                 break;
1311                         case Opt_xprt_tcp:
1312                                 mnt->flags |= NFS_MOUNT_TCP;
1313                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1314                                 kfree(string);
1315                                 break;
1316                         case Opt_xprt_rdma:
1317                                 /* vector side protocols to TCP */
1318                                 mnt->flags |= NFS_MOUNT_TCP;
1319                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1320                                 xprt_load_transport(string);
1321                                 kfree(string);
1322                                 break;
1323                         default:
1324                                 dfprintk(MOUNT, "NFS:   unrecognized "
1325                                                 "transport protocol\n");
1326                                 return 0;
1327                         }
1328                         break;
1329                 case Opt_mountproto:
1330                         string = match_strdup(args);
1331                         if (string == NULL)
1332                                 goto out_nomem;
1333                         token = match_token(string,
1334                                             nfs_xprt_protocol_tokens, args);
1335                         kfree(string);
1336
1337                         switch (token) {
1338                         case Opt_xprt_udp:
1339                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1340                                 break;
1341                         case Opt_xprt_tcp:
1342                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1343                                 break;
1344                         case Opt_xprt_rdma: /* not used for side protocols */
1345                         default:
1346                                 dfprintk(MOUNT, "NFS:   unrecognized "
1347                                                 "transport protocol\n");
1348                                 return 0;
1349                         }
1350                         break;
1351                 case Opt_addr:
1352                         string = match_strdup(args);
1353                         if (string == NULL)
1354                                 goto out_nomem;
1355                         nfs_parse_ip_address(string, strlen(string),
1356                                              (struct sockaddr *)
1357                                                 &mnt->nfs_server.address,
1358                                              &mnt->nfs_server.addrlen);
1359                         kfree(string);
1360                         break;
1361                 case Opt_clientaddr:
1362                         string = match_strdup(args);
1363                         if (string == NULL)
1364                                 goto out_nomem;
1365                         kfree(mnt->client_address);
1366                         mnt->client_address = string;
1367                         break;
1368                 case Opt_mounthost:
1369                         string = match_strdup(args);
1370                         if (string == NULL)
1371                                 goto out_nomem;
1372                         kfree(mnt->mount_server.hostname);
1373                         mnt->mount_server.hostname = string;
1374                         break;
1375                 case Opt_mountaddr:
1376                         string = match_strdup(args);
1377                         if (string == NULL)
1378                                 goto out_nomem;
1379                         nfs_parse_ip_address(string, strlen(string),
1380                                              (struct sockaddr *)
1381                                                 &mnt->mount_server.address,
1382                                              &mnt->mount_server.addrlen);
1383                         kfree(string);
1384                         break;
1385                 case Opt_lookupcache:
1386                         string = match_strdup(args);
1387                         if (string == NULL)
1388                                 goto out_nomem;
1389                         token = match_token(string,
1390                                         nfs_lookupcache_tokens, args);
1391                         kfree(string);
1392                         switch (token) {
1393                                 case Opt_lookupcache_all:
1394                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1395                                         break;
1396                                 case Opt_lookupcache_positive:
1397                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1398                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1399                                         break;
1400                                 case Opt_lookupcache_none:
1401                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1402                                         break;
1403                                 default:
1404                                         dfprintk(MOUNT, "NFS:   invalid "
1405                                                         "lookupcache argument\n");
1406                                         return 0;
1407                         };
1408                         break;
1409
1410                 /*
1411                  * Special options
1412                  */
1413                 case Opt_sloppy:
1414                         sloppy = 1;
1415                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1416                         break;
1417                 case Opt_userspace:
1418                 case Opt_deprecated:
1419                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1420                                         "'%s'\n", p);
1421                         break;
1422
1423                 default:
1424                         invalid_option = 1;
1425                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1426                                         "'%s'\n", p);
1427                 }
1428         }
1429
1430         if (!sloppy && invalid_option)
1431                 return 0;
1432
1433         return 1;
1434
1435 out_invalid_value:
1436         printk(KERN_INFO "NFS: bad mount option value specified: %s \n", p);
1437         return 0;
1438 out_nomem:
1439         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1440         return 0;
1441 out_security_failure:
1442         free_secdata(secdata);
1443         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1444         return 0;
1445 }
1446
1447 /*
1448  * Use the remote server's MOUNT service to request the NFS file handle
1449  * corresponding to the provided path.
1450  */
1451 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1452                          struct nfs_fh *root_fh)
1453 {
1454         unsigned int auth_flavor_len = 0;
1455         struct nfs_mount_request request = {
1456                 .sap            = (struct sockaddr *)
1457                                                 &args->mount_server.address,
1458                 .dirpath        = args->nfs_server.export_path,
1459                 .protocol       = args->mount_server.protocol,
1460                 .fh             = root_fh,
1461                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1462                 .auth_flav_len  = &auth_flavor_len,
1463         };
1464         int status;
1465
1466         if (args->mount_server.version == 0) {
1467                 if (args->flags & NFS_MOUNT_VER3)
1468                         args->mount_server.version = NFS_MNT3_VERSION;
1469                 else
1470                         args->mount_server.version = NFS_MNT_VERSION;
1471         }
1472         request.version = args->mount_server.version;
1473
1474         if (args->mount_server.hostname)
1475                 request.hostname = args->mount_server.hostname;
1476         else
1477                 request.hostname = args->nfs_server.hostname;
1478
1479         /*
1480          * Construct the mount server's address.
1481          */
1482         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1483                 memcpy(request.sap, &args->nfs_server.address,
1484                        args->nfs_server.addrlen);
1485                 args->mount_server.addrlen = args->nfs_server.addrlen;
1486         }
1487         request.salen = args->mount_server.addrlen;
1488
1489         /*
1490          * autobind will be used if mount_server.port == 0
1491          */
1492         nfs_set_port(request.sap, args->mount_server.port);
1493
1494         /*
1495          * Now ask the mount server to map our export path
1496          * to a file handle.
1497          */
1498         status = nfs_mount(&request);
1499         if (status == 0)
1500                 return 0;
1501
1502         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1503                         request.hostname, status);
1504         return status;
1505 }
1506
1507 static int nfs_parse_simple_hostname(const char *dev_name,
1508                                      char **hostname, size_t maxnamlen,
1509                                      char **export_path, size_t maxpathlen)
1510 {
1511         size_t len;
1512         char *colon, *comma;
1513
1514         colon = strchr(dev_name, ':');
1515         if (colon == NULL)
1516                 goto out_bad_devname;
1517
1518         len = colon - dev_name;
1519         if (len > maxnamlen)
1520                 goto out_hostname;
1521
1522         /* N.B. caller will free nfs_server.hostname in all cases */
1523         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1524         if (!*hostname)
1525                 goto out_nomem;
1526
1527         /* kill possible hostname list: not supported */
1528         comma = strchr(*hostname, ',');
1529         if (comma != NULL) {
1530                 if (comma == *hostname)
1531                         goto out_bad_devname;
1532                 *comma = '\0';
1533         }
1534
1535         colon++;
1536         len = strlen(colon);
1537         if (len > maxpathlen)
1538                 goto out_path;
1539         *export_path = kstrndup(colon, len, GFP_KERNEL);
1540         if (!*export_path)
1541                 goto out_nomem;
1542
1543         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1544         return 0;
1545
1546 out_bad_devname:
1547         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1548         return -EINVAL;
1549
1550 out_nomem:
1551         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1552         return -ENOMEM;
1553
1554 out_hostname:
1555         dfprintk(MOUNT, "NFS: server hostname too long\n");
1556         return -ENAMETOOLONG;
1557
1558 out_path:
1559         dfprintk(MOUNT, "NFS: export pathname too long\n");
1560         return -ENAMETOOLONG;
1561 }
1562
1563 /*
1564  * Hostname has square brackets around it because it contains one or
1565  * more colons.  We look for the first closing square bracket, and a
1566  * colon must follow it.
1567  */
1568 static int nfs_parse_protected_hostname(const char *dev_name,
1569                                         char **hostname, size_t maxnamlen,
1570                                         char **export_path, size_t maxpathlen)
1571 {
1572         size_t len;
1573         char *start, *end;
1574
1575         start = (char *)(dev_name + 1);
1576
1577         end = strchr(start, ']');
1578         if (end == NULL)
1579                 goto out_bad_devname;
1580         if (*(end + 1) != ':')
1581                 goto out_bad_devname;
1582
1583         len = end - start;
1584         if (len > maxnamlen)
1585                 goto out_hostname;
1586
1587         /* N.B. caller will free nfs_server.hostname in all cases */
1588         *hostname = kstrndup(start, len, GFP_KERNEL);
1589         if (*hostname == NULL)
1590                 goto out_nomem;
1591
1592         end += 2;
1593         len = strlen(end);
1594         if (len > maxpathlen)
1595                 goto out_path;
1596         *export_path = kstrndup(end, len, GFP_KERNEL);
1597         if (!*export_path)
1598                 goto out_nomem;
1599
1600         return 0;
1601
1602 out_bad_devname:
1603         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1604         return -EINVAL;
1605
1606 out_nomem:
1607         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1608         return -ENOMEM;
1609
1610 out_hostname:
1611         dfprintk(MOUNT, "NFS: server hostname too long\n");
1612         return -ENAMETOOLONG;
1613
1614 out_path:
1615         dfprintk(MOUNT, "NFS: export pathname too long\n");
1616         return -ENAMETOOLONG;
1617 }
1618
1619 /*
1620  * Split "dev_name" into "hostname:export_path".
1621  *
1622  * The leftmost colon demarks the split between the server's hostname
1623  * and the export path.  If the hostname starts with a left square
1624  * bracket, then it may contain colons.
1625  *
1626  * Note: caller frees hostname and export path, even on error.
1627  */
1628 static int nfs_parse_devname(const char *dev_name,
1629                              char **hostname, size_t maxnamlen,
1630                              char **export_path, size_t maxpathlen)
1631 {
1632         if (*dev_name == '[')
1633                 return nfs_parse_protected_hostname(dev_name,
1634                                                     hostname, maxnamlen,
1635                                                     export_path, maxpathlen);
1636
1637         return nfs_parse_simple_hostname(dev_name,
1638                                          hostname, maxnamlen,
1639                                          export_path, maxpathlen);
1640 }
1641
1642 /*
1643  * Validate the NFS2/NFS3 mount data
1644  * - fills in the mount root filehandle
1645  *
1646  * For option strings, user space handles the following behaviors:
1647  *
1648  * + DNS: mapping server host name to IP address ("addr=" option)
1649  *
1650  * + failure mode: how to behave if a mount request can't be handled
1651  *   immediately ("fg/bg" option)
1652  *
1653  * + retry: how often to retry a mount request ("retry=" option)
1654  *
1655  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1656  *   mountproto=tcp after mountproto=udp, and so on
1657  */
1658 static int nfs_validate_mount_data(void *options,
1659                                    struct nfs_parsed_mount_data *args,
1660                                    struct nfs_fh *mntfh,
1661                                    const char *dev_name)
1662 {
1663         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1664
1665         if (data == NULL)
1666                 goto out_no_data;
1667
1668         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1669         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1670         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1671         args->acregmin          = NFS_DEF_ACREGMIN;
1672         args->acregmax          = NFS_DEF_ACREGMAX;
1673         args->acdirmin          = NFS_DEF_ACDIRMIN;
1674         args->acdirmax          = NFS_DEF_ACDIRMAX;
1675         args->mount_server.port = 0;    /* autobind unless user sets port */
1676         args->nfs_server.port   = 0;    /* autobind unless user sets port */
1677         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1678         args->auth_flavors[0]   = RPC_AUTH_UNIX;
1679
1680         switch (data->version) {
1681         case 1:
1682                 data->namlen = 0;
1683         case 2:
1684                 data->bsize = 0;
1685         case 3:
1686                 if (data->flags & NFS_MOUNT_VER3)
1687                         goto out_no_v3;
1688                 data->root.size = NFS2_FHSIZE;
1689                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1690         case 4:
1691                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1692                         goto out_no_sec;
1693         case 5:
1694                 memset(data->context, 0, sizeof(data->context));
1695         case 6:
1696                 if (data->flags & NFS_MOUNT_VER3) {
1697                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1698                                 goto out_invalid_fh;
1699                         mntfh->size = data->root.size;
1700                 } else
1701                         mntfh->size = NFS2_FHSIZE;
1702
1703
1704                 memcpy(mntfh->data, data->root.data, mntfh->size);
1705                 if (mntfh->size < sizeof(mntfh->data))
1706                         memset(mntfh->data + mntfh->size, 0,
1707                                sizeof(mntfh->data) - mntfh->size);
1708
1709                 /*
1710                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1711                  * can deal with.
1712                  */
1713                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1714                 args->rsize             = data->rsize;
1715                 args->wsize             = data->wsize;
1716                 args->timeo             = data->timeo;
1717                 args->retrans           = data->retrans;
1718                 args->acregmin          = data->acregmin;
1719                 args->acregmax          = data->acregmax;
1720                 args->acdirmin          = data->acdirmin;
1721                 args->acdirmax          = data->acdirmax;
1722
1723                 memcpy(&args->nfs_server.address, &data->addr,
1724                        sizeof(data->addr));
1725                 args->nfs_server.addrlen = sizeof(data->addr);
1726                 if (!nfs_verify_server_address((struct sockaddr *)
1727                                                 &args->nfs_server.address))
1728                         goto out_no_address;
1729
1730                 if (!(data->flags & NFS_MOUNT_TCP))
1731                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1732                 /* N.B. caller will free nfs_server.hostname in all cases */
1733                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1734                 args->namlen            = data->namlen;
1735                 args->bsize             = data->bsize;
1736
1737                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1738                         args->auth_flavors[0] = data->pseudoflavor;
1739                 if (!args->nfs_server.hostname)
1740                         goto out_nomem;
1741
1742                 /*
1743                  * The legacy version 6 binary mount data from userspace has a
1744                  * field used only to transport selinux information into the
1745                  * the kernel.  To continue to support that functionality we
1746                  * have a touch of selinux knowledge here in the NFS code. The
1747                  * userspace code converted context=blah to just blah so we are
1748                  * converting back to the full string selinux understands.
1749                  */
1750                 if (data->context[0]){
1751 #ifdef CONFIG_SECURITY_SELINUX
1752                         int rc;
1753                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1754                         if (!opts_str)
1755                                 return -ENOMEM;
1756                         strcpy(opts_str, "context=");
1757                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1758                         strcat(opts_str, &data->context[0]);
1759                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1760                         kfree(opts_str);
1761                         if (rc)
1762                                 return rc;
1763 #else
1764                         return -EINVAL;
1765 #endif
1766                 }
1767
1768                 break;
1769         default: {
1770                 int status;
1771
1772                 if (nfs_parse_mount_options((char *)options, args) == 0)
1773                         return -EINVAL;
1774
1775                 if (!nfs_verify_server_address((struct sockaddr *)
1776                                                 &args->nfs_server.address))
1777                         goto out_no_address;
1778
1779                 nfs_set_port((struct sockaddr *)&args->nfs_server.address,
1780                                 args->nfs_server.port);
1781
1782                 nfs_set_mount_transport_protocol(args);
1783
1784                 status = nfs_parse_devname(dev_name,
1785                                            &args->nfs_server.hostname,
1786                                            PAGE_SIZE,
1787                                            &args->nfs_server.export_path,
1788                                            NFS_MAXPATHLEN);
1789                 if (!status)
1790                         status = nfs_try_mount(args, mntfh);
1791
1792                 kfree(args->nfs_server.export_path);
1793                 args->nfs_server.export_path = NULL;
1794
1795                 if (status)
1796                         return status;
1797
1798                 break;
1799                 }
1800         }
1801
1802 #ifndef CONFIG_NFS_V3
1803         if (args->flags & NFS_MOUNT_VER3)
1804                 goto out_v3_not_compiled;
1805 #endif /* !CONFIG_NFS_V3 */
1806
1807         return 0;
1808
1809 out_no_data:
1810         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1811         return -EINVAL;
1812
1813 out_no_v3:
1814         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1815                  data->version);
1816         return -EINVAL;
1817
1818 out_no_sec:
1819         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1820         return -EINVAL;
1821
1822 #ifndef CONFIG_NFS_V3
1823 out_v3_not_compiled:
1824         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1825         return -EPROTONOSUPPORT;
1826 #endif /* !CONFIG_NFS_V3 */
1827
1828 out_nomem:
1829         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1830         return -ENOMEM;
1831
1832 out_no_address:
1833         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1834         return -EINVAL;
1835
1836 out_invalid_fh:
1837         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1838         return -EINVAL;
1839 }
1840
1841 static int
1842 nfs_compare_remount_data(struct nfs_server *nfss,
1843                          struct nfs_parsed_mount_data *data)
1844 {
1845         if (data->flags != nfss->flags ||
1846             data->rsize != nfss->rsize ||
1847             data->wsize != nfss->wsize ||
1848             data->retrans != nfss->client->cl_timeout->to_retries ||
1849             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1850             data->acregmin != nfss->acregmin / HZ ||
1851             data->acregmax != nfss->acregmax / HZ ||
1852             data->acdirmin != nfss->acdirmin / HZ ||
1853             data->acdirmax != nfss->acdirmax / HZ ||
1854             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1855             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1856             memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1857                    data->nfs_server.addrlen) != 0)
1858                 return -EINVAL;
1859
1860         return 0;
1861 }
1862
1863 static int
1864 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1865 {
1866         int error;
1867         struct nfs_server *nfss = sb->s_fs_info;
1868         struct nfs_parsed_mount_data *data;
1869         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1870         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1871         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1872
1873         /*
1874          * Userspace mount programs that send binary options generally send
1875          * them populated with default values. We have no way to know which
1876          * ones were explicitly specified. Fall back to legacy behavior and
1877          * just return success.
1878          */
1879         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1880             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1881                                            options->version <= 6))))
1882                 return 0;
1883
1884         data = kzalloc(sizeof(*data), GFP_KERNEL);
1885         if (data == NULL)
1886                 return -ENOMEM;
1887
1888         lock_kernel();
1889         /* fill out struct with values from existing mount */
1890         data->flags = nfss->flags;
1891         data->rsize = nfss->rsize;
1892         data->wsize = nfss->wsize;
1893         data->retrans = nfss->client->cl_timeout->to_retries;
1894         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1895         data->acregmin = nfss->acregmin / HZ;
1896         data->acregmax = nfss->acregmax / HZ;
1897         data->acdirmin = nfss->acdirmin / HZ;
1898         data->acdirmax = nfss->acdirmax / HZ;
1899         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1900         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1901         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1902                 data->nfs_server.addrlen);
1903
1904         /* overwrite those values with any that were specified */
1905         error = nfs_parse_mount_options((char *)options, data);
1906         if (error < 0)
1907                 goto out;
1908
1909         /* compare new mount options with old ones */
1910         error = nfs_compare_remount_data(nfss, data);
1911 out:
1912         kfree(data);
1913         unlock_kernel();
1914         return error;
1915 }
1916
1917 /*
1918  * Initialise the common bits of the superblock
1919  */
1920 static inline void nfs_initialise_sb(struct super_block *sb)
1921 {
1922         struct nfs_server *server = NFS_SB(sb);
1923
1924         sb->s_magic = NFS_SUPER_MAGIC;
1925
1926         /* We probably want something more informative here */
1927         snprintf(sb->s_id, sizeof(sb->s_id),
1928                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1929
1930         if (sb->s_blocksize == 0)
1931                 sb->s_blocksize = nfs_block_bits(server->wsize,
1932                                                  &sb->s_blocksize_bits);
1933
1934         if (server->flags & NFS_MOUNT_NOAC)
1935                 sb->s_flags |= MS_SYNCHRONOUS;
1936
1937         nfs_super_set_maxbytes(sb, server->maxfilesize);
1938 }
1939
1940 /*
1941  * Finish setting up an NFS2/3 superblock
1942  */
1943 static void nfs_fill_super(struct super_block *sb,
1944                            struct nfs_parsed_mount_data *data)
1945 {
1946         struct nfs_server *server = NFS_SB(sb);
1947
1948         sb->s_blocksize_bits = 0;
1949         sb->s_blocksize = 0;
1950         if (data->bsize)
1951                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1952
1953         if (server->flags & NFS_MOUNT_VER3) {
1954                 /* The VFS shouldn't apply the umask to mode bits. We will do
1955                  * so ourselves when necessary.
1956                  */
1957                 sb->s_flags |= MS_POSIXACL;
1958                 sb->s_time_gran = 1;
1959         }
1960
1961         sb->s_op = &nfs_sops;
1962         nfs_initialise_sb(sb);
1963 }
1964
1965 /*
1966  * Finish setting up a cloned NFS2/3 superblock
1967  */
1968 static void nfs_clone_super(struct super_block *sb,
1969                             const struct super_block *old_sb)
1970 {
1971         struct nfs_server *server = NFS_SB(sb);
1972
1973         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1974         sb->s_blocksize = old_sb->s_blocksize;
1975         sb->s_maxbytes = old_sb->s_maxbytes;
1976
1977         if (server->flags & NFS_MOUNT_VER3) {
1978                 /* The VFS shouldn't apply the umask to mode bits. We will do
1979                  * so ourselves when necessary.
1980                  */
1981                 sb->s_flags |= MS_POSIXACL;
1982                 sb->s_time_gran = 1;
1983         }
1984
1985         sb->s_op = old_sb->s_op;
1986         nfs_initialise_sb(sb);
1987 }
1988
1989 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1990 {
1991         const struct nfs_server *a = s->s_fs_info;
1992         const struct rpc_clnt *clnt_a = a->client;
1993         const struct rpc_clnt *clnt_b = b->client;
1994
1995         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1996                 goto Ebusy;
1997         if (a->nfs_client != b->nfs_client)
1998                 goto Ebusy;
1999         if (a->flags != b->flags)
2000                 goto Ebusy;
2001         if (a->wsize != b->wsize)
2002                 goto Ebusy;
2003         if (a->rsize != b->rsize)
2004                 goto Ebusy;
2005         if (a->acregmin != b->acregmin)
2006                 goto Ebusy;
2007         if (a->acregmax != b->acregmax)
2008                 goto Ebusy;
2009         if (a->acdirmin != b->acdirmin)
2010                 goto Ebusy;
2011         if (a->acdirmax != b->acdirmax)
2012                 goto Ebusy;
2013         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2014                 goto Ebusy;
2015         return 1;
2016 Ebusy:
2017         return 0;
2018 }
2019
2020 struct nfs_sb_mountdata {
2021         struct nfs_server *server;
2022         int mntflags;
2023 };
2024
2025 static int nfs_set_super(struct super_block *s, void *data)
2026 {
2027         struct nfs_sb_mountdata *sb_mntdata = data;
2028         struct nfs_server *server = sb_mntdata->server;
2029         int ret;
2030
2031         s->s_flags = sb_mntdata->mntflags;
2032         s->s_fs_info = server;
2033         ret = set_anon_super(s, server);
2034         if (ret == 0)
2035                 server->s_dev = s->s_dev;
2036         return ret;
2037 }
2038
2039 static int nfs_compare_super_address(struct nfs_server *server1,
2040                                      struct nfs_server *server2)
2041 {
2042         struct sockaddr *sap1, *sap2;
2043
2044         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2045         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2046
2047         if (sap1->sa_family != sap2->sa_family)
2048                 return 0;
2049
2050         switch (sap1->sa_family) {
2051         case AF_INET: {
2052                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2053                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2054                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2055                         return 0;
2056                 if (sin1->sin_port != sin2->sin_port)
2057                         return 0;
2058                 break;
2059         }
2060         case AF_INET6: {
2061                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2062                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2063                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2064                         return 0;
2065                 if (sin1->sin6_port != sin2->sin6_port)
2066                         return 0;
2067                 break;
2068         }
2069         default:
2070                 return 0;
2071         }
2072
2073         return 1;
2074 }
2075
2076 static int nfs_compare_super(struct super_block *sb, void *data)
2077 {
2078         struct nfs_sb_mountdata *sb_mntdata = data;
2079         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2080         int mntflags = sb_mntdata->mntflags;
2081
2082         if (!nfs_compare_super_address(old, server))
2083                 return 0;
2084         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2085         if (old->flags & NFS_MOUNT_UNSHARED)
2086                 return 0;
2087         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2088                 return 0;
2089         return nfs_compare_mount_options(sb, server, mntflags);
2090 }
2091
2092 static int nfs_bdi_register(struct nfs_server *server)
2093 {
2094         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2095 }
2096
2097 static int nfs_get_sb(struct file_system_type *fs_type,
2098         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2099 {
2100         struct nfs_server *server = NULL;
2101         struct super_block *s;
2102         struct nfs_parsed_mount_data *data;
2103         struct nfs_fh *mntfh;
2104         struct dentry *mntroot;
2105         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2106         struct nfs_sb_mountdata sb_mntdata = {
2107                 .mntflags = flags,
2108         };
2109         int error = -ENOMEM;
2110
2111         data = kzalloc(sizeof(*data), GFP_KERNEL);
2112         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2113         if (data == NULL || mntfh == NULL)
2114                 goto out_free_fh;
2115
2116         security_init_mnt_opts(&data->lsm_opts);
2117
2118         /* Validate the mount data */
2119         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2120         if (error < 0)
2121                 goto out;
2122
2123         /* Get a volume representation */
2124         server = nfs_create_server(data, mntfh);
2125         if (IS_ERR(server)) {
2126                 error = PTR_ERR(server);
2127                 goto out;
2128         }
2129         sb_mntdata.server = server;
2130
2131         if (server->flags & NFS_MOUNT_UNSHARED)
2132                 compare_super = NULL;
2133
2134         /* Get a superblock - note that we may end up sharing one that already exists */
2135         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2136         if (IS_ERR(s)) {
2137                 error = PTR_ERR(s);
2138                 goto out_err_nosb;
2139         }
2140
2141         if (s->s_fs_info != server) {
2142                 nfs_free_server(server);
2143                 server = NULL;
2144         } else {
2145                 error = nfs_bdi_register(server);
2146                 if (error)
2147                         goto error_splat_super;
2148         }
2149
2150         if (!s->s_root) {
2151                 /* initial superblock/root creation */
2152                 nfs_fill_super(s, data);
2153                 nfs_fscache_get_super_cookie(s, data);
2154         }
2155
2156         mntroot = nfs_get_root(s, mntfh);
2157         if (IS_ERR(mntroot)) {
2158                 error = PTR_ERR(mntroot);
2159                 goto error_splat_super;
2160         }
2161
2162         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2163         if (error)
2164                 goto error_splat_root;
2165
2166         s->s_flags |= MS_ACTIVE;
2167         mnt->mnt_sb = s;
2168         mnt->mnt_root = mntroot;
2169         error = 0;
2170
2171 out:
2172         kfree(data->nfs_server.hostname);
2173         kfree(data->mount_server.hostname);
2174         kfree(data->fscache_uniq);
2175         security_free_mnt_opts(&data->lsm_opts);
2176 out_free_fh:
2177         kfree(mntfh);
2178         kfree(data);
2179         return error;
2180
2181 out_err_nosb:
2182         nfs_free_server(server);
2183         goto out;
2184
2185 error_splat_root:
2186         dput(mntroot);
2187 error_splat_super:
2188         deactivate_locked_super(s);
2189         goto out;
2190 }
2191
2192 /*
2193  * Destroy an NFS2/3 superblock
2194  */
2195 static void nfs_kill_super(struct super_block *s)
2196 {
2197         struct nfs_server *server = NFS_SB(s);
2198
2199         bdi_unregister(&server->backing_dev_info);
2200         kill_anon_super(s);
2201         nfs_fscache_release_super_cookie(s);
2202         nfs_free_server(server);
2203 }
2204
2205 /*
2206  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2207  */
2208 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
2209                            const char *dev_name, void *raw_data,
2210                            struct vfsmount *mnt)
2211 {
2212         struct nfs_clone_mount *data = raw_data;
2213         struct super_block *s;
2214         struct nfs_server *server;
2215         struct dentry *mntroot;
2216         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2217         struct nfs_sb_mountdata sb_mntdata = {
2218                 .mntflags = flags,
2219         };
2220         int error;
2221
2222         dprintk("--> nfs_xdev_get_sb()\n");
2223
2224         /* create a new volume representation */
2225         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2226         if (IS_ERR(server)) {
2227                 error = PTR_ERR(server);
2228                 goto out_err_noserver;
2229         }
2230         sb_mntdata.server = server;
2231
2232         if (server->flags & NFS_MOUNT_UNSHARED)
2233                 compare_super = NULL;
2234
2235         /* Get a superblock - note that we may end up sharing one that already exists */
2236         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2237         if (IS_ERR(s)) {
2238                 error = PTR_ERR(s);
2239                 goto out_err_nosb;
2240         }
2241
2242         if (s->s_fs_info != server) {
2243                 nfs_free_server(server);
2244                 server = NULL;
2245         } else {
2246                 error = nfs_bdi_register(server);
2247                 if (error)
2248                         goto error_splat_super;
2249         }
2250
2251         if (!s->s_root) {
2252                 /* initial superblock/root creation */
2253                 nfs_clone_super(s, data->sb);
2254         }
2255
2256         mntroot = nfs_get_root(s, data->fh);
2257         if (IS_ERR(mntroot)) {
2258                 error = PTR_ERR(mntroot);
2259                 goto error_splat_super;
2260         }
2261         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2262                 dput(mntroot);
2263                 error = -ESTALE;
2264                 goto error_splat_super;
2265         }
2266
2267         s->s_flags |= MS_ACTIVE;
2268         mnt->mnt_sb = s;
2269         mnt->mnt_root = mntroot;
2270
2271         /* clone any lsm security options from the parent to the new sb */
2272         security_sb_clone_mnt_opts(data->sb, s);
2273
2274         dprintk("<-- nfs_xdev_get_sb() = 0\n");
2275         return 0;
2276
2277 out_err_nosb:
2278         nfs_free_server(server);
2279 out_err_noserver:
2280         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
2281         return error;
2282
2283 error_splat_super:
2284         deactivate_locked_super(s);
2285         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
2286         return error;
2287 }
2288
2289 #ifdef CONFIG_NFS_V4
2290
2291 /*
2292  * Finish setting up a cloned NFS4 superblock
2293  */
2294 static void nfs4_clone_super(struct super_block *sb,
2295                             const struct super_block *old_sb)
2296 {
2297         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2298         sb->s_blocksize = old_sb->s_blocksize;
2299         sb->s_maxbytes = old_sb->s_maxbytes;
2300         sb->s_time_gran = 1;
2301         sb->s_op = old_sb->s_op;
2302         nfs_initialise_sb(sb);
2303 }
2304
2305 /*
2306  * Set up an NFS4 superblock
2307  */
2308 static void nfs4_fill_super(struct super_block *sb)
2309 {
2310         sb->s_time_gran = 1;
2311         sb->s_op = &nfs4_sops;
2312         nfs_initialise_sb(sb);
2313 }
2314
2315 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2316 {
2317         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3);
2318 }
2319
2320 /*
2321  * Validate NFSv4 mount options
2322  */
2323 static int nfs4_validate_mount_data(void *options,
2324                                     struct nfs_parsed_mount_data *args,
2325                                     const char *dev_name)
2326 {
2327         struct sockaddr_in *ap;
2328         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2329         char *c;
2330
2331         if (data == NULL)
2332                 goto out_no_data;
2333
2334         args->rsize             = NFS_MAX_FILE_IO_SIZE;
2335         args->wsize             = NFS_MAX_FILE_IO_SIZE;
2336         args->acregmin          = NFS_DEF_ACREGMIN;
2337         args->acregmax          = NFS_DEF_ACREGMAX;
2338         args->acdirmin          = NFS_DEF_ACDIRMIN;
2339         args->acdirmax          = NFS_DEF_ACDIRMAX;
2340         args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
2341         args->auth_flavors[0]   = RPC_AUTH_UNIX;
2342         args->auth_flavor_len   = 0;
2343         args->minorversion      = 0;
2344
2345         switch (data->version) {
2346         case 1:
2347                 ap = (struct sockaddr_in *)&args->nfs_server.address;
2348                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2349                         goto out_no_address;
2350                 if (data->host_addrlen == 0)
2351                         goto out_no_address;
2352                 args->nfs_server.addrlen = data->host_addrlen;
2353                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
2354                         return -EFAULT;
2355                 if (!nfs_verify_server_address((struct sockaddr *)
2356                                                 &args->nfs_server.address))
2357                         goto out_no_address;
2358
2359                 if (data->auth_flavourlen) {
2360                         if (data->auth_flavourlen > 1)
2361                                 goto out_inval_auth;
2362                         if (copy_from_user(&args->auth_flavors[0],
2363                                            data->auth_flavours,
2364                                            sizeof(args->auth_flavors[0])))
2365                                 return -EFAULT;
2366                 }
2367
2368                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2369                 if (IS_ERR(c))
2370                         return PTR_ERR(c);
2371                 args->nfs_server.hostname = c;
2372
2373                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2374                 if (IS_ERR(c))
2375                         return PTR_ERR(c);
2376                 args->nfs_server.export_path = c;
2377                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2378
2379                 c = strndup_user(data->client_addr.data, 16);
2380                 if (IS_ERR(c))
2381                         return PTR_ERR(c);
2382                 args->client_address = c;
2383
2384                 /*
2385                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2386                  * can deal with.
2387                  */
2388
2389                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2390                 args->rsize     = data->rsize;
2391                 args->wsize     = data->wsize;
2392                 args->timeo     = data->timeo;
2393                 args->retrans   = data->retrans;
2394                 args->acregmin  = data->acregmin;
2395                 args->acregmax  = data->acregmax;
2396                 args->acdirmin  = data->acdirmin;
2397                 args->acdirmax  = data->acdirmax;
2398                 args->nfs_server.protocol = data->proto;
2399                 nfs_validate_transport_protocol(args);
2400
2401                 break;
2402         default: {
2403                 int status;
2404
2405                 if (nfs_parse_mount_options((char *)options, args) == 0)
2406                         return -EINVAL;
2407
2408                 if (!nfs_verify_server_address((struct sockaddr *)
2409                                                 &args->nfs_server.address))
2410                         return -EINVAL;
2411
2412                 nfs_set_port((struct sockaddr *)&args->nfs_server.address,
2413                                 args->nfs_server.port);
2414
2415                 nfs_validate_transport_protocol(args);
2416
2417                 nfs4_validate_mount_flags(args);
2418
2419                 if (args->auth_flavor_len > 1)
2420                         goto out_inval_auth;
2421
2422                 if (args->client_address == NULL)
2423                         goto out_no_client_address;
2424
2425                 status = nfs_parse_devname(dev_name,
2426                                            &args->nfs_server.hostname,
2427                                            NFS4_MAXNAMLEN,
2428                                            &args->nfs_server.export_path,
2429                                            NFS4_MAXPATHLEN);
2430                 if (status < 0)
2431                         return status;
2432
2433                 break;
2434                 }
2435         }
2436
2437         return 0;
2438
2439 out_no_data:
2440         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2441         return -EINVAL;
2442
2443 out_inval_auth:
2444         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2445                  data->auth_flavourlen);
2446         return -EINVAL;
2447
2448 out_no_address:
2449         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2450         return -EINVAL;
2451
2452 out_no_client_address:
2453         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
2454         return -EINVAL;
2455 }
2456
2457 /*
2458  * Get the superblock for the NFS4 root partition
2459  */
2460 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
2461         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2462 {
2463         struct nfs_parsed_mount_data *data = raw_data;
2464         struct super_block *s;
2465         struct nfs_server *server;
2466         struct nfs_fh *mntfh;
2467         struct dentry *mntroot;
2468         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2469         struct nfs_sb_mountdata sb_mntdata = {
2470                 .mntflags = flags,
2471         };
2472         int error = -ENOMEM;
2473
2474         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2475         if (data == NULL || mntfh == NULL)
2476                 goto out_free_fh;
2477
2478         security_init_mnt_opts(&data->lsm_opts);
2479
2480         /* Get a volume representation */
2481         server = nfs4_create_server(data, mntfh);
2482         if (IS_ERR(server)) {
2483                 error = PTR_ERR(server);
2484                 goto out;
2485         }
2486         sb_mntdata.server = server;
2487
2488         if (server->flags & NFS4_MOUNT_UNSHARED)
2489                 compare_super = NULL;
2490
2491         /* Get a superblock - note that we may end up sharing one that already exists */
2492         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2493         if (IS_ERR(s)) {
2494                 error = PTR_ERR(s);
2495                 goto out_free;
2496         }
2497
2498         if (s->s_fs_info != server) {
2499                 nfs_free_server(server);
2500                 server = NULL;
2501         } else {
2502                 error = nfs_bdi_register(server);
2503                 if (error)
2504                         goto error_splat_super;
2505         }
2506
2507         if (!s->s_root) {
2508                 /* initial superblock/root creation */
2509                 nfs4_fill_super(s);
2510                 nfs_fscache_get_super_cookie(s, data);
2511         }
2512
2513         mntroot = nfs4_get_root(s, mntfh);
2514         if (IS_ERR(mntroot)) {
2515                 error = PTR_ERR(mntroot);
2516                 goto error_splat_super;
2517         }
2518
2519         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2520         if (error)
2521                 goto error_splat_root;
2522
2523         s->s_flags |= MS_ACTIVE;
2524         mnt->mnt_sb = s;
2525         mnt->mnt_root = mntroot;
2526         error = 0;
2527
2528 out:
2529         security_free_mnt_opts(&data->lsm_opts);
2530 out_free_fh:
2531         kfree(mntfh);
2532         return error;
2533
2534 out_free:
2535         nfs_free_server(server);
2536         goto out;
2537
2538 error_splat_root:
2539         dput(mntroot);
2540 error_splat_super:
2541         deactivate_locked_super(s);
2542         goto out;
2543 }
2544
2545 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2546                 int flags, void *data, const char *hostname)
2547 {
2548         struct vfsmount *root_mnt;
2549         char *root_devname;
2550         size_t len;
2551
2552         len = strlen(hostname) + 3;
2553         root_devname = kmalloc(len, GFP_KERNEL);
2554         if (root_devname == NULL)
2555                 return ERR_PTR(-ENOMEM);
2556         snprintf(root_devname, len, "%s:/", hostname);
2557         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2558         kfree(root_devname);
2559         return root_mnt;
2560 }
2561
2562 static void nfs_fix_devname(const struct path *path, struct vfsmount *mnt)
2563 {
2564         char *page = (char *) __get_free_page(GFP_KERNEL);
2565         char *devname, *tmp;
2566
2567         if (page == NULL)
2568                 return;
2569         devname = nfs_path(path->mnt->mnt_devname,
2570                         path->mnt->mnt_root, path->dentry,
2571                         page, PAGE_SIZE);
2572         if (devname == NULL)
2573                 goto out_freepage;
2574         tmp = kstrdup(devname, GFP_KERNEL);
2575         if (tmp == NULL)
2576                 goto out_freepage;
2577         kfree(mnt->mnt_devname);
2578         mnt->mnt_devname = tmp;
2579 out_freepage:
2580         free_page((unsigned long)page);
2581 }
2582
2583 static int nfs_follow_remote_path(struct vfsmount *root_mnt,
2584                 const char *export_path, struct vfsmount *mnt_target)
2585 {
2586         struct mnt_namespace *ns_private;
2587         struct nameidata nd;
2588         struct super_block *s;
2589         int ret;
2590
2591         ns_private = create_mnt_ns(root_mnt);
2592         ret = PTR_ERR(ns_private);
2593         if (IS_ERR(ns_private))
2594                 goto out_mntput;
2595
2596         ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
2597                         export_path, LOOKUP_FOLLOW, &nd);
2598
2599         put_mnt_ns(ns_private);
2600
2601         if (ret != 0)
2602                 goto out_err;
2603
2604         s = nd.path.mnt->mnt_sb;
2605         atomic_inc(&s->s_active);
2606         mnt_target->mnt_sb = s;
2607         mnt_target->mnt_root = dget(nd.path.dentry);
2608
2609         /* Correct the device pathname */
2610         nfs_fix_devname(&nd.path, mnt_target);
2611
2612         path_put(&nd.path);
2613         down_write(&s->s_umount);
2614         return 0;
2615 out_mntput:
2616         mntput(root_mnt);
2617 out_err:
2618         return ret;
2619 }
2620
2621 /*
2622  * Get the superblock for an NFS4 mountpoint
2623  */
2624 static int nfs4_get_sb(struct file_system_type *fs_type,
2625         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2626 {
2627         struct nfs_parsed_mount_data *data;
2628         char *export_path;
2629         struct vfsmount *root_mnt;
2630         int error = -ENOMEM;
2631
2632         data = kzalloc(sizeof(*data), GFP_KERNEL);
2633         if (data == NULL)
2634                 goto out_free_data;
2635
2636         /* Validate the mount data */
2637         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2638         if (error < 0)
2639                 goto out;
2640
2641         export_path = data->nfs_server.export_path;
2642         data->nfs_server.export_path = "/";
2643         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2644                         data->nfs_server.hostname);
2645         data->nfs_server.export_path = export_path;
2646
2647         error = PTR_ERR(root_mnt);
2648         if (IS_ERR(root_mnt))
2649                 goto out;
2650
2651         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
2652
2653 out:
2654         kfree(data->client_address);
2655         kfree(data->nfs_server.export_path);
2656         kfree(data->nfs_server.hostname);
2657         kfree(data->fscache_uniq);
2658 out_free_data:
2659         kfree(data);
2660         dprintk("<-- nfs4_get_sb() = %d%s\n", error,
2661                         error != 0 ? " [error]" : "");
2662         return error;
2663 }
2664
2665 static void nfs4_kill_super(struct super_block *sb)
2666 {
2667         struct nfs_server *server = NFS_SB(sb);
2668
2669         dprintk("--> %s\n", __func__);
2670         nfs_super_return_all_delegations(sb);
2671         kill_anon_super(sb);
2672         nfs4_renewd_prepare_shutdown(server);
2673         nfs_fscache_release_super_cookie(sb);
2674         nfs_free_server(server);
2675         dprintk("<-- %s\n", __func__);
2676 }
2677
2678 /*
2679  * Clone an NFS4 server record on xdev traversal (FSID-change)
2680  */
2681 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2682                             const char *dev_name, void *raw_data,
2683                             struct vfsmount *mnt)
2684 {
2685         struct nfs_clone_mount *data = raw_data;
2686         struct super_block *s;
2687         struct nfs_server *server;
2688         struct dentry *mntroot;
2689         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2690         struct nfs_sb_mountdata sb_mntdata = {
2691                 .mntflags = flags,
2692         };
2693         int error;
2694
2695         dprintk("--> nfs4_xdev_get_sb()\n");
2696
2697         /* create a new volume representation */
2698         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2699         if (IS_ERR(server)) {
2700                 error = PTR_ERR(server);
2701                 goto out_err_noserver;
2702         }
2703         sb_mntdata.server = server;
2704
2705         if (server->flags & NFS4_MOUNT_UNSHARED)
2706                 compare_super = NULL;
2707
2708         /* Get a superblock - note that we may end up sharing one that already exists */
2709         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2710         if (IS_ERR(s)) {
2711                 error = PTR_ERR(s);
2712                 goto out_err_nosb;
2713         }
2714
2715         if (s->s_fs_info != server) {
2716                 nfs_free_server(server);
2717                 server = NULL;
2718         } else {
2719                 error = nfs_bdi_register(server);
2720                 if (error)
2721                         goto error_splat_super;
2722         }
2723
2724         if (!s->s_root) {
2725                 /* initial superblock/root creation */
2726                 nfs4_clone_super(s, data->sb);
2727         }
2728
2729         mntroot = nfs4_get_root(s, data->fh);
2730         if (IS_ERR(mntroot)) {
2731                 error = PTR_ERR(mntroot);
2732                 goto error_splat_super;
2733         }
2734         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2735                 dput(mntroot);
2736                 error = -ESTALE;
2737                 goto error_splat_super;
2738         }
2739
2740         s->s_flags |= MS_ACTIVE;
2741         mnt->mnt_sb = s;
2742         mnt->mnt_root = mntroot;
2743
2744         security_sb_clone_mnt_opts(data->sb, s);
2745
2746         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2747         return 0;
2748
2749 out_err_nosb:
2750         nfs_free_server(server);
2751 out_err_noserver:
2752         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2753         return error;
2754
2755 error_splat_super:
2756         deactivate_locked_super(s);
2757         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2758         return error;
2759 }
2760
2761 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
2762                 int flags, const char *dev_name, void *raw_data,
2763                 struct vfsmount *mnt)
2764 {
2765         struct nfs_clone_mount *data = raw_data;
2766         struct super_block *s;
2767         struct nfs_server *server;
2768         struct dentry *mntroot;
2769         struct nfs_fh mntfh;
2770         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2771         struct nfs_sb_mountdata sb_mntdata = {
2772                 .mntflags = flags,
2773         };
2774         int error;
2775
2776         dprintk("--> nfs4_referral_get_sb()\n");
2777
2778         /* create a new volume representation */
2779         server = nfs4_create_referral_server(data, &mntfh);
2780         if (IS_ERR(server)) {
2781                 error = PTR_ERR(server);
2782                 goto out_err_noserver;
2783         }
2784         sb_mntdata.server = server;
2785
2786         if (server->flags & NFS4_MOUNT_UNSHARED)
2787                 compare_super = NULL;
2788
2789         /* Get a superblock - note that we may end up sharing one that already exists */
2790         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2791         if (IS_ERR(s)) {
2792                 error = PTR_ERR(s);
2793                 goto out_err_nosb;
2794         }
2795
2796         if (s->s_fs_info != server) {
2797                 nfs_free_server(server);
2798                 server = NULL;
2799         } else {
2800                 error = nfs_bdi_register(server);
2801                 if (error)
2802                         goto error_splat_super;
2803         }
2804
2805         if (!s->s_root) {
2806                 /* initial superblock/root creation */
2807                 nfs4_fill_super(s);
2808         }
2809
2810         mntroot = nfs4_get_root(s, &mntfh);
2811         if (IS_ERR(mntroot)) {
2812                 error = PTR_ERR(mntroot);
2813                 goto error_splat_super;
2814         }
2815         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2816                 dput(mntroot);
2817                 error = -ESTALE;
2818                 goto error_splat_super;
2819         }
2820
2821         s->s_flags |= MS_ACTIVE;
2822         mnt->mnt_sb = s;
2823         mnt->mnt_root = mntroot;
2824
2825         security_sb_clone_mnt_opts(data->sb, s);
2826
2827         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2828         return 0;
2829
2830 out_err_nosb:
2831         nfs_free_server(server);
2832 out_err_noserver:
2833         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2834         return error;
2835
2836 error_splat_super:
2837         deactivate_locked_super(s);
2838         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2839         return error;
2840 }
2841
2842 /*
2843  * Create an NFS4 server record on referral traversal
2844  */
2845 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
2846                 int flags, const char *dev_name, void *raw_data,
2847                 struct vfsmount *mnt)
2848 {
2849         struct nfs_clone_mount *data = raw_data;
2850         char *export_path;
2851         struct vfsmount *root_mnt;
2852         int error;
2853
2854         dprintk("--> nfs4_referral_get_sb()\n");
2855
2856         export_path = data->mnt_path;
2857         data->mnt_path = "/";
2858
2859         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
2860                         flags, data, data->hostname);
2861         data->mnt_path = export_path;
2862
2863         error = PTR_ERR(root_mnt);
2864         if (IS_ERR(root_mnt))
2865                 goto out;
2866
2867         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
2868 out:
2869         dprintk("<-- nfs4_referral_get_sb() = %d%s\n", error,
2870                         error != 0 ? " [error]" : "");
2871         return error;
2872 }
2873
2874 #endif /* CONFIG_NFS_V4 */