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 <linux/slab.h>
  52 #include <net/ipv6.h>
  53 #include <linux/netdevice.h>
  54 #include <linux/nfs_xdr.h>
  55 #include <linux/magic.h>
  56 #include <linux/parser.h>
  57
  58 #include <asm/system.h>
  59 #include <asm/uaccess.h>
  60
  61 #include "nfs4_fs.h"
  62 #include "callback.h"
  63 #include "delegation.h"
  64 #include "iostat.h"
  65 #include "internal.h"
  66 #include "fscache.h"
  67
  68 #define NFSDBG_FACILITY         NFSDBG_VFS
  69
  70 enum {
  71         /* Mount options that take no arguments */
  72         Opt_soft, Opt_hard,
  73         Opt_posix, Opt_noposix,
  74         Opt_cto, Opt_nocto,
  75         Opt_ac, Opt_noac,
  76         Opt_lock, Opt_nolock,
  77         Opt_v2, Opt_v3, Opt_v4,
  78         Opt_udp, Opt_tcp, Opt_rdma,
  79         Opt_acl, Opt_noacl,
  80         Opt_rdirplus, Opt_nordirplus,
  81         Opt_sharecache, Opt_nosharecache,
  82         Opt_resvport, Opt_noresvport,
  83         Opt_fscache, Opt_nofscache,
  84
  85         /* Mount options that take integer arguments */
  86         Opt_port,
  87         Opt_rsize, Opt_wsize, Opt_bsize,
  88         Opt_timeo, Opt_retrans,
  89         Opt_acregmin, Opt_acregmax,
  90         Opt_acdirmin, Opt_acdirmax,
  91         Opt_actimeo,
  92         Opt_namelen,
  93         Opt_mountport,
  94         Opt_mountvers,
  95         Opt_nfsvers,
  96         Opt_minorversion,
  97
  98         /* Mount options that take string arguments */
  99         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 100         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 101         Opt_lookupcache,
 102         Opt_fscache_uniq,
 103
 104         /* Special mount options */
 105         Opt_userspace, Opt_deprecated, Opt_sloppy,
 106
 107         Opt_err
 108 };
 109
 110 static const match_table_t nfs_mount_option_tokens = {
 111         { Opt_userspace, "bg" },
 112         { Opt_userspace, "fg" },
 113         { Opt_userspace, "retry=%s" },
 114
 115         { Opt_sloppy, "sloppy" },
 116
 117         { Opt_soft, "soft" },
 118         { Opt_hard, "hard" },
 119         { Opt_deprecated, "intr" },
 120         { Opt_deprecated, "nointr" },
 121         { Opt_posix, "posix" },
 122         { Opt_noposix, "noposix" },
 123         { Opt_cto, "cto" },
 124         { Opt_nocto, "nocto" },
 125         { Opt_ac, "ac" },
 126         { Opt_noac, "noac" },
 127         { Opt_lock, "lock" },
 128         { Opt_nolock, "nolock" },
 129         { Opt_v2, "v2" },
 130         { Opt_v3, "v3" },
 131         { Opt_v4, "v4" },
 132         { Opt_udp, "udp" },
 133         { Opt_tcp, "tcp" },
 134         { Opt_rdma, "rdma" },
 135         { Opt_acl, "acl" },
 136         { Opt_noacl, "noacl" },
 137         { Opt_rdirplus, "rdirplus" },
 138         { Opt_nordirplus, "nordirplus" },
 139         { Opt_sharecache, "sharecache" },
 140         { Opt_nosharecache, "nosharecache" },
 141         { Opt_resvport, "resvport" },
 142         { Opt_noresvport, "noresvport" },
 143         { Opt_fscache, "fsc" },
 144         { Opt_nofscache, "nofsc" },
 145
 146         { Opt_port, "port=%s" },
 147         { Opt_rsize, "rsize=%s" },
 148         { Opt_wsize, "wsize=%s" },
 149         { Opt_bsize, "bsize=%s" },
 150         { Opt_timeo, "timeo=%s" },
 151         { Opt_retrans, "retrans=%s" },
 152         { Opt_acregmin, "acregmin=%s" },
 153         { Opt_acregmax, "acregmax=%s" },
 154         { Opt_acdirmin, "acdirmin=%s" },
 155         { Opt_acdirmax, "acdirmax=%s" },
 156         { Opt_actimeo, "actimeo=%s" },
 157         { Opt_namelen, "namlen=%s" },
 158         { Opt_mountport, "mountport=%s" },
 159         { Opt_mountvers, "mountvers=%s" },
 160         { Opt_nfsvers, "nfsvers=%s" },
 161         { Opt_nfsvers, "vers=%s" },
 162         { Opt_minorversion, "minorversion=%s" },
 163
 164         { Opt_sec, "sec=%s" },
 165         { Opt_proto, "proto=%s" },
 166         { Opt_mountproto, "mountproto=%s" },
 167         { Opt_addr, "addr=%s" },
 168         { Opt_clientaddr, "clientaddr=%s" },
 169         { Opt_mounthost, "mounthost=%s" },
 170         { Opt_mountaddr, "mountaddr=%s" },
 171
 172         { Opt_lookupcache, "lookupcache=%s" },
 173         { Opt_fscache_uniq, "fsc=%s" },
 174
 175         { Opt_err, NULL }
 176 };
 177
 178 enum {
 179         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 180
 181         Opt_xprt_err
 182 };
 183
 184 static const match_table_t nfs_xprt_protocol_tokens = {
 185         { Opt_xprt_udp, "udp" },
 186         { Opt_xprt_udp6, "udp6" },
 187         { Opt_xprt_tcp, "tcp" },
 188         { Opt_xprt_tcp6, "tcp6" },
 189         { Opt_xprt_rdma, "rdma" },
 190
 191         { Opt_xprt_err, NULL }
 192 };
 193
 194 enum {
 195         Opt_sec_none, Opt_sec_sys,
 196         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 197         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 198         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 199
 200         Opt_sec_err
 201 };
 202
 203 static const match_table_t nfs_secflavor_tokens = {
 204         { Opt_sec_none, "none" },
 205         { Opt_sec_none, "null" },
 206         { Opt_sec_sys, "sys" },
 207
 208         { Opt_sec_krb5, "krb5" },
 209         { Opt_sec_krb5i, "krb5i" },
 210         { Opt_sec_krb5p, "krb5p" },
 211
 212         { Opt_sec_lkey, "lkey" },
 213         { Opt_sec_lkeyi, "lkeyi" },
 214         { Opt_sec_lkeyp, "lkeyp" },
 215
 216         { Opt_sec_spkm, "spkm3" },
 217         { Opt_sec_spkmi, "spkm3i" },
 218         { Opt_sec_spkmp, "spkm3p" },
 219
 220         { Opt_sec_err, NULL }
 221 };
 222
 223 enum {
 224         Opt_lookupcache_all, Opt_lookupcache_positive,
 225         Opt_lookupcache_none,
 226
 227         Opt_lookupcache_err
 228 };
 229
 230 static match_table_t nfs_lookupcache_tokens = {
 231         { Opt_lookupcache_all, "all" },
 232         { Opt_lookupcache_positive, "pos" },
 233         { Opt_lookupcache_positive, "positive" },
 234         { Opt_lookupcache_none, "none" },
 235
 236         { Opt_lookupcache_err, NULL }
 237 };
 238
 239
 240 static void nfs_umount_begin(struct super_block *);
 241 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 242 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 243 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 244 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 245 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 246                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 247 static void nfs_put_super(struct super_block *);
 248 static void nfs_kill_super(struct super_block *);
 249 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 250
 251 static struct file_system_type nfs_fs_type = {
 252         .owner          = THIS_MODULE,
 253         .name           = "nfs",
 254         .get_sb         = nfs_get_sb,
 255         .kill_sb        = nfs_kill_super,
 256         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 257 };
 258
 259 struct file_system_type nfs_xdev_fs_type = {
 260         .owner          = THIS_MODULE,
 261         .name           = "nfs",
 262         .get_sb         = nfs_xdev_get_sb,
 263         .kill_sb        = nfs_kill_super,
 264         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 265 };
 266
 267 static const struct super_operations nfs_sops = {
 268         .alloc_inode    = nfs_alloc_inode,
 269         .destroy_inode  = nfs_destroy_inode,
 270         .write_inode    = nfs_write_inode,
 271         .put_super      = nfs_put_super,
 272         .statfs         = nfs_statfs,
 273         .clear_inode    = nfs_clear_inode,
 274         .umount_begin   = nfs_umount_begin,
 275         .show_options   = nfs_show_options,
 276         .show_stats     = nfs_show_stats,
 277         .remount_fs     = nfs_remount,
 278 };
 279
 280 #ifdef CONFIG_NFS_V4
 281 static int nfs4_validate_text_mount_data(void *options,
 282         struct nfs_parsed_mount_data *args, const char *dev_name);
 283 static int nfs4_try_mount(int flags, const char *dev_name,
 284         struct nfs_parsed_mount_data *data, struct vfsmount *mnt);
 285 static int nfs4_get_sb(struct file_system_type *fs_type,
 286         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 287 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
 288         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 289 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 290         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 291 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 292         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 293 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
 294         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 295 static void nfs4_kill_super(struct super_block *sb);
 296
 297 static struct file_system_type nfs4_fs_type = {
 298         .owner          = THIS_MODULE,
 299         .name           = "nfs4",
 300         .get_sb         = nfs4_get_sb,
 301         .kill_sb        = nfs4_kill_super,
 302         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 303 };
 304
 305 static struct file_system_type nfs4_remote_fs_type = {
 306         .owner          = THIS_MODULE,
 307         .name           = "nfs4",
 308         .get_sb         = nfs4_remote_get_sb,
 309         .kill_sb        = nfs4_kill_super,
 310         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 311 };
 312
 313 struct file_system_type nfs4_xdev_fs_type = {
 314         .owner          = THIS_MODULE,
 315         .name           = "nfs4",
 316         .get_sb         = nfs4_xdev_get_sb,
 317         .kill_sb        = nfs4_kill_super,
 318         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 319 };
 320
 321 static struct file_system_type nfs4_remote_referral_fs_type = {
 322         .owner          = THIS_MODULE,
 323         .name           = "nfs4",
 324         .get_sb         = nfs4_remote_referral_get_sb,
 325         .kill_sb        = nfs4_kill_super,
 326         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 327 };
 328
 329 struct file_system_type nfs4_referral_fs_type = {
 330         .owner          = THIS_MODULE,
 331         .name           = "nfs4",
 332         .get_sb         = nfs4_referral_get_sb,
 333         .kill_sb        = nfs4_kill_super,
 334         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 335 };
 336
 337 static const struct super_operations nfs4_sops = {
 338         .alloc_inode    = nfs_alloc_inode,
 339         .destroy_inode  = nfs_destroy_inode,
 340         .write_inode    = nfs_write_inode,
 341         .put_super      = nfs_put_super,
 342         .statfs         = nfs_statfs,
 343         .clear_inode    = nfs4_clear_inode,
 344         .umount_begin   = nfs_umount_begin,
 345         .show_options   = nfs_show_options,
 346         .show_stats     = nfs_show_stats,
 347         .remount_fs     = nfs_remount,
 348 };
 349 #endif
 350
 351 static struct shrinker acl_shrinker = {
 352         .shrink         = nfs_access_cache_shrinker,
 353         .seeks          = DEFAULT_SEEKS,
 354 };
 355
 356 /*
 357  * Register the NFS filesystems
 358  */
 359 int __init register_nfs_fs(void)
 360 {
 361         int ret;
 362
 363         ret = register_filesystem(&nfs_fs_type);
 364         if (ret < 0)
 365                 goto error_0;
 366
 367         ret = nfs_register_sysctl();
 368         if (ret < 0)
 369                 goto error_1;
 370 #ifdef CONFIG_NFS_V4
 371         ret = register_filesystem(&nfs4_fs_type);
 372         if (ret < 0)
 373                 goto error_2;
 374 #endif
 375         register_shrinker(&acl_shrinker);
 376         return 0;
 377
 378 #ifdef CONFIG_NFS_V4
 379 error_2:
 380         nfs_unregister_sysctl();
 381 #endif
 382 error_1:
 383         unregister_filesystem(&nfs_fs_type);
 384 error_0:
 385         return ret;
 386 }
 387
 388 /*
 389  * Unregister the NFS filesystems
 390  */
 391 void __exit unregister_nfs_fs(void)
 392 {
 393         unregister_shrinker(&acl_shrinker);
 394 #ifdef CONFIG_NFS_V4
 395         unregister_filesystem(&nfs4_fs_type);
 396 #endif
 397         nfs_unregister_sysctl();
 398         unregister_filesystem(&nfs_fs_type);
 399 }
 400
 401 void nfs_sb_active(struct super_block *sb)
 402 {
 403         struct nfs_server *server = NFS_SB(sb);
 404
 405         if (atomic_inc_return(&server->active) == 1)
 406                 atomic_inc(&sb->s_active);
 407 }
 408
 409 void nfs_sb_deactive(struct super_block *sb)
 410 {
 411         struct nfs_server *server = NFS_SB(sb);
 412
 413         if (atomic_dec_and_test(&server->active))
 414                 deactivate_super(sb);
 415 }
 416
 417 /*
 418  * Deliver file system statistics to userspace
 419  */
 420 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 421 {
 422         struct nfs_server *server = NFS_SB(dentry->d_sb);
 423         unsigned char blockbits;
 424         unsigned long blockres;
 425         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 426         struct nfs_fsstat res;
 427         int error = -ENOMEM;
 428
 429         res.fattr = nfs_alloc_fattr();
 430         if (res.fattr == NULL)
 431                 goto out_err;
 432
 433         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 434
 435         nfs_free_fattr(res.fattr);
 436         if (error < 0)
 437                 goto out_err;
 438
 439         buf->f_type = NFS_SUPER_MAGIC;
 440
 441         /*
 442          * Current versions of glibc do not correctly handle the
 443          * case where f_frsize != f_bsize.  Eventually we want to
 444          * report the value of wtmult in this field.
 445          */
 446         buf->f_frsize = dentry->d_sb->s_blocksize;
 447
 448         /*
 449          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 450          * are reported in units of f_frsize.  Linux hasn't had
 451          * an f_frsize field in its statfs struct until recently,
 452          * thus historically Linux's sys_statfs reports these
 453          * fields in units of f_bsize.
 454          */
 455         buf->f_bsize = dentry->d_sb->s_blocksize;
 456         blockbits = dentry->d_sb->s_blocksize_bits;
 457         blockres = (1 << blockbits) - 1;
 458         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 459         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 460         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 461
 462         buf->f_files = res.tfiles;
 463         buf->f_ffree = res.afiles;
 464
 465         buf->f_namelen = server->namelen;
 466
 467         return 0;
 468
 469  out_err:
 470         dprintk("%s: statfs error = %d\n", __func__, -error);
 471         return error;
 472 }
 473
 474 /*
 475  * Map the security flavour number to a name
 476  */
 477 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 478 {
 479         static const struct {
 480                 rpc_authflavor_t flavour;
 481                 const char *str;
 482         } sec_flavours[] = {
 483                 { RPC_AUTH_NULL, "null" },
 484                 { RPC_AUTH_UNIX, "sys" },
 485                 { RPC_AUTH_GSS_KRB5, "krb5" },
 486                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 487                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 488                 { RPC_AUTH_GSS_LKEY, "lkey" },
 489                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 490                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 491                 { RPC_AUTH_GSS_SPKM, "spkm" },
 492                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 493                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 494                 { UINT_MAX, "unknown" }
 495         };
 496         int i;
 497
 498         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 499                 if (sec_flavours[i].flavour == flavour)
 500                         break;
 501         }
 502         return sec_flavours[i].str;
 503 }
 504
 505 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 506                                   int showdefaults)
 507 {
 508         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 509
 510         seq_printf(m, ",mountproto=");
 511         switch (sap->sa_family) {
 512         case AF_INET:
 513                 switch (nfss->mountd_protocol) {
 514                 case IPPROTO_UDP:
 515                         seq_printf(m, RPCBIND_NETID_UDP);
 516                         break;
 517                 case IPPROTO_TCP:
 518                         seq_printf(m, RPCBIND_NETID_TCP);
 519                         break;
 520                 default:
 521                         if (showdefaults)
 522                                 seq_printf(m, "auto");
 523                 }
 524                 break;
 525         case AF_INET6:
 526                 switch (nfss->mountd_protocol) {
 527                 case IPPROTO_UDP:
 528                         seq_printf(m, RPCBIND_NETID_UDP6);
 529                         break;
 530                 case IPPROTO_TCP:
 531                         seq_printf(m, RPCBIND_NETID_TCP6);
 532                         break;
 533                 default:
 534                         if (showdefaults)
 535                                 seq_printf(m, "auto");
 536                 }
 537                 break;
 538         default:
 539                 if (showdefaults)
 540                         seq_printf(m, "auto");
 541         }
 542 }
 543
 544 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 545                                     int showdefaults)
 546 {
 547         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 548
 549         switch (sap->sa_family) {
 550         case AF_INET: {
 551                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 552                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 553                 break;
 554         }
 555         case AF_INET6: {
 556                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 557                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 558                 break;
 559         }
 560         default:
 561                 if (showdefaults)
 562                         seq_printf(m, ",mountaddr=unspecified");
 563         }
 564
 565         if (nfss->mountd_version || showdefaults)
 566                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 567         if (nfss->mountd_port || showdefaults)
 568                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 569
 570         nfs_show_mountd_netid(m, nfss, showdefaults);
 571 }
 572
 573 /*
 574  * Describe the mount options in force on this server representation
 575  */
 576 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 577                                    int showdefaults)
 578 {
 579         static const struct proc_nfs_info {
 580                 int flag;
 581                 const char *str;
 582                 const char *nostr;
 583         } nfs_info[] = {
 584                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 585                 { NFS_MOUNT_POSIX, ",posix", "" },
 586                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 587                 { NFS_MOUNT_NOAC, ",noac", "" },
 588                 { NFS_MOUNT_NONLM, ",nolock", "" },
 589                 { NFS_MOUNT_NOACL, ",noacl", "" },
 590                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 591                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 592                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 593                 { 0, NULL, NULL }
 594         };
 595         const struct proc_nfs_info *nfs_infop;
 596         struct nfs_client *clp = nfss->nfs_client;
 597         u32 version = clp->rpc_ops->version;
 598
 599         seq_printf(m, ",vers=%u", version);
 600         seq_printf(m, ",rsize=%u", nfss->rsize);
 601         seq_printf(m, ",wsize=%u", nfss->wsize);
 602         if (nfss->bsize != 0)
 603                 seq_printf(m, ",bsize=%u", nfss->bsize);
 604         seq_printf(m, ",namlen=%u", nfss->namelen);
 605         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 606                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 607         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 608                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 609         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 610                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 611         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 612                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 613         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 614                 if (nfss->flags & nfs_infop->flag)
 615                         seq_puts(m, nfs_infop->str);
 616                 else
 617                         seq_puts(m, nfs_infop->nostr);
 618         }
 619         seq_printf(m, ",proto=%s",
 620                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 621         if (version == 4) {
 622                 if (nfss->port != NFS_PORT)
 623                         seq_printf(m, ",port=%u", nfss->port);
 624         } else
 625                 if (nfss->port)
 626                         seq_printf(m, ",port=%u", nfss->port);
 627
 628         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 629         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 630         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 631
 632         if (version != 4)
 633                 nfs_show_mountd_options(m, nfss, showdefaults);
 634
 635 #ifdef CONFIG_NFS_V4
 636         if (clp->rpc_ops->version == 4)
 637                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 638 #endif
 639         if (nfss->options & NFS_OPTION_FSCACHE)
 640                 seq_printf(m, ",fsc");
 641 }
 642
 643 /*
 644  * Describe the mount options on this VFS mountpoint
 645  */
 646 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 647 {
 648         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 649
 650         nfs_show_mount_options(m, nfss, 0);
 651
 652         seq_printf(m, ",addr=%s",
 653                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 654                                                         RPC_DISPLAY_ADDR));
 655
 656         return 0;
 657 }
 658
 659 /*
 660  * Present statistical information for this VFS mountpoint
 661  */
 662 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 663 {
 664         int i, cpu;
 665         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 666         struct rpc_auth *auth = nfss->client->cl_auth;
 667         struct nfs_iostats totals = { };
 668
 669         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 670
 671         /*
 672          * Display all mount option settings
 673          */
 674         seq_printf(m, "\n\topts:\t");
 675         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 676         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 677         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 678         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 679         nfs_show_mount_options(m, nfss, 1);
 680
 681         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 682
 683         seq_printf(m, "\n\tcaps:\t");
 684         seq_printf(m, "caps=0x%x", nfss->caps);
 685         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 686         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 687         seq_printf(m, ",bsize=%u", nfss->bsize);
 688         seq_printf(m, ",namlen=%u", nfss->namelen);
 689
 690 #ifdef CONFIG_NFS_V4
 691         if (nfss->nfs_client->rpc_ops->version == 4) {
 692                 seq_printf(m, "\n\tnfsv4:\t");
 693                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 694                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 695                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 696         }
 697 #endif
 698
 699         /*
 700          * Display security flavor in effect for this mount
 701          */
 702         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 703         if (auth->au_flavor)
 704                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 705
 706         /*
 707          * Display superblock I/O counters
 708          */
 709         for_each_possible_cpu(cpu) {
 710                 struct nfs_iostats *stats;
 711
 712                 preempt_disable();
 713                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 714
 715                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 716                         totals.events[i] += stats->events[i];
 717                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 718                         totals.bytes[i] += stats->bytes[i];
 719 #ifdef CONFIG_NFS_FSCACHE
 720                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 721                         totals.fscache[i] += stats->fscache[i];
 722 #endif
 723
 724                 preempt_enable();
 725         }
 726
 727         seq_printf(m, "\n\tevents:\t");
 728         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 729                 seq_printf(m, "%lu ", totals.events[i]);
 730         seq_printf(m, "\n\tbytes:\t");
 731         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 732                 seq_printf(m, "%Lu ", totals.bytes[i]);
 733 #ifdef CONFIG_NFS_FSCACHE
 734         if (nfss->options & NFS_OPTION_FSCACHE) {
 735                 seq_printf(m, "\n\tfsc:\t");
 736                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 737                         seq_printf(m, "%Lu ", totals.bytes[i]);
 738         }
 739 #endif
 740         seq_printf(m, "\n");
 741
 742         rpc_print_iostats(m, nfss->client);
 743
 744         return 0;
 745 }
 746
 747 /*
 748  * Begin unmount by attempting to remove all automounted mountpoints we added
 749  * in response to xdev traversals and referrals
 750  */
 751 static void nfs_umount_begin(struct super_block *sb)
 752 {
 753         struct nfs_server *server;
 754         struct rpc_clnt *rpc;
 755
 756         server = NFS_SB(sb);
 757         /* -EIO all pending I/O */
 758         rpc = server->client_acl;
 759         if (!IS_ERR(rpc))
 760                 rpc_killall_tasks(rpc);
 761         rpc = server->client;
 762         if (!IS_ERR(rpc))
 763                 rpc_killall_tasks(rpc);
 764 }
 765
 766 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
 767 {
 768         struct nfs_parsed_mount_data *data;
 769
 770         data = kzalloc(sizeof(*data), GFP_KERNEL);
 771         if (data) {
 772                 data->acregmin          = NFS_DEF_ACREGMIN;
 773                 data->acregmax          = NFS_DEF_ACREGMAX;
 774                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 775                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 776                 data->mount_server.port = NFS_UNSPEC_PORT;
 777                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 778                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 779                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 780                 data->auth_flavor_len   = 1;
 781                 data->version           = version;
 782                 data->minorversion      = 0;
 783         }
 784         return data;
 785 }
 786
 787 /*
 788  * Sanity-check a server address provided by the mount command.
 789  *
 790  * Address family must be initialized, and address must not be
 791  * the ANY address for that family.
 792  */
 793 static int nfs_verify_server_address(struct sockaddr *addr)
 794 {
 795         switch (addr->sa_family) {
 796         case AF_INET: {
 797                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 798                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 799         }
 800         case AF_INET6: {
 801                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 802                 return !ipv6_addr_any(sa);
 803         }
 804         }
 805
 806         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 807         return 0;
 808 }
 809
 810 /*
 811  * Select between a default port value and a user-specified port value.
 812  * If a zero value is set, then autobind will be used.
 813  */
 814 static void nfs_set_port(struct sockaddr *sap, int *port,
 815                                  const unsigned short default_port)
 816 {
 817         if (*port == NFS_UNSPEC_PORT)
 818                 *port = default_port;
 819
 820         rpc_set_port(sap, *port);
 821 }
 822
 823 /*
 824  * Sanity check the NFS transport protocol.
 825  *
 826  */
 827 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 828 {
 829         switch (mnt->nfs_server.protocol) {
 830         case XPRT_TRANSPORT_UDP:
 831         case XPRT_TRANSPORT_TCP:
 832         case XPRT_TRANSPORT_RDMA:
 833                 break;
 834         default:
 835                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 836         }
 837 }
 838
 839 /*
 840  * For text based NFSv2/v3 mounts, the mount protocol transport default
 841  * settings should depend upon the specified NFS transport.
 842  */
 843 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 844 {
 845         nfs_validate_transport_protocol(mnt);
 846
 847         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 848             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 849                         return;
 850         switch (mnt->nfs_server.protocol) {
 851         case XPRT_TRANSPORT_UDP:
 852                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 853                 break;
 854         case XPRT_TRANSPORT_TCP:
 855         case XPRT_TRANSPORT_RDMA:
 856                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 857         }
 858 }
 859
 860 /*
 861  * Parse the value of the 'sec=' option.
 862  */
 863 static int nfs_parse_security_flavors(char *value,
 864                                       struct nfs_parsed_mount_data *mnt)
 865 {
 866         substring_t args[MAX_OPT_ARGS];
 867
 868         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 869
 870         switch (match_token(value, nfs_secflavor_tokens, args)) {
 871         case Opt_sec_none:
 872                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 873                 break;
 874         case Opt_sec_sys:
 875                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 876                 break;
 877         case Opt_sec_krb5:
 878                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 879                 break;
 880         case Opt_sec_krb5i:
 881                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 882                 break;
 883         case Opt_sec_krb5p:
 884                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 885                 break;
 886         case Opt_sec_lkey:
 887                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 888                 break;
 889         case Opt_sec_lkeyi:
 890                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 891                 break;
 892         case Opt_sec_lkeyp:
 893                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 894                 break;
 895         case Opt_sec_spkm:
 896                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
 897                 break;
 898         case Opt_sec_spkmi:
 899                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
 900                 break;
 901         case Opt_sec_spkmp:
 902                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
 903                 break;
 904         default:
 905                 return 0;
 906         }
 907
 908         mnt->auth_flavor_len = 1;
 909         return 1;
 910 }
 911
 912 /*
 913  * Error-check and convert a string of mount options from user space into
 914  * a data structure.  The whole mount string is processed; bad options are
 915  * skipped as they are encountered.  If there were no errors, return 1;
 916  * otherwise return 0 (zero).
 917  */
 918 static int nfs_parse_mount_options(char *raw,
 919                                    struct nfs_parsed_mount_data *mnt)
 920 {
 921         char *p, *string, *secdata;
 922         int rc, sloppy = 0, invalid_option = 0;
 923         unsigned short protofamily = AF_UNSPEC;
 924         unsigned short mountfamily = AF_UNSPEC;
 925
 926         if (!raw) {
 927                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 928                 return 1;
 929         }
 930         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 931
 932         secdata = alloc_secdata();
 933         if (!secdata)
 934                 goto out_nomem;
 935
 936         rc = security_sb_copy_data(raw, secdata);
 937         if (rc)
 938                 goto out_security_failure;
 939
 940         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 941         if (rc)
 942                 goto out_security_failure;
 943
 944         free_secdata(secdata);
 945
 946         while ((p = strsep(&raw, ",")) != NULL) {
 947                 substring_t args[MAX_OPT_ARGS];
 948                 unsigned long option;
 949                 int token;
 950
 951                 if (!*p)
 952                         continue;
 953
 954                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 955
 956                 token = match_token(p, nfs_mount_option_tokens, args);
 957                 switch (token) {
 958
 959                 /*
 960                  * boolean options:  foo/nofoo
 961                  */
 962                 case Opt_soft:
 963                         mnt->flags |= NFS_MOUNT_SOFT;
 964                         break;
 965                 case Opt_hard:
 966                         mnt->flags &= ~NFS_MOUNT_SOFT;
 967                         break;
 968                 case Opt_posix:
 969                         mnt->flags |= NFS_MOUNT_POSIX;
 970                         break;
 971                 case Opt_noposix:
 972                         mnt->flags &= ~NFS_MOUNT_POSIX;
 973                         break;
 974                 case Opt_cto:
 975                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 976                         break;
 977                 case Opt_nocto:
 978                         mnt->flags |= NFS_MOUNT_NOCTO;
 979                         break;
 980                 case Opt_ac:
 981                         mnt->flags &= ~NFS_MOUNT_NOAC;
 982                         break;
 983                 case Opt_noac:
 984                         mnt->flags |= NFS_MOUNT_NOAC;
 985                         break;
 986                 case Opt_lock:
 987                         mnt->flags &= ~NFS_MOUNT_NONLM;
 988                         break;
 989                 case Opt_nolock:
 990                         mnt->flags |= NFS_MOUNT_NONLM;
 991                         break;
 992                 case Opt_v2:
 993                         mnt->flags &= ~NFS_MOUNT_VER3;
 994                         mnt->version = 2;
 995                         break;
 996                 case Opt_v3:
 997                         mnt->flags |= NFS_MOUNT_VER3;
 998                         mnt->version = 3;
 999                         break;
1000 #ifdef CONFIG_NFS_V4
1001                 case Opt_v4:
1002                         mnt->flags &= ~NFS_MOUNT_VER3;
1003                         mnt->version = 4;
1004                         break;
1005 #endif
1006                 case Opt_udp:
1007                         mnt->flags &= ~NFS_MOUNT_TCP;
1008                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1009                         break;
1010                 case Opt_tcp:
1011                         mnt->flags |= NFS_MOUNT_TCP;
1012                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1013                         break;
1014                 case Opt_rdma:
1015                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1016                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1017                         xprt_load_transport(p);
1018                         break;
1019                 case Opt_acl:
1020                         mnt->flags &= ~NFS_MOUNT_NOACL;
1021                         break;
1022                 case Opt_noacl:
1023                         mnt->flags |= NFS_MOUNT_NOACL;
1024                         break;
1025                 case Opt_rdirplus:
1026                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1027                         break;
1028                 case Opt_nordirplus:
1029                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1030                         break;
1031                 case Opt_sharecache:
1032                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1033                         break;
1034                 case Opt_nosharecache:
1035                         mnt->flags |= NFS_MOUNT_UNSHARED;
1036                         break;
1037                 case Opt_resvport:
1038                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1039                         break;
1040                 case Opt_noresvport:
1041                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1042                         break;
1043                 case Opt_fscache:
1044                         mnt->options |= NFS_OPTION_FSCACHE;
1045                         kfree(mnt->fscache_uniq);
1046                         mnt->fscache_uniq = NULL;
1047                         break;
1048                 case Opt_nofscache:
1049                         mnt->options &= ~NFS_OPTION_FSCACHE;
1050                         kfree(mnt->fscache_uniq);
1051                         mnt->fscache_uniq = NULL;
1052                         break;
1053
1054                 /*
1055                  * options that take numeric values
1056                  */
1057                 case Opt_port:
1058                         string = match_strdup(args);
1059                         if (string == NULL)
1060                                 goto out_nomem;
1061                         rc = strict_strtoul(string, 10, &option);
1062                         kfree(string);
1063                         if (rc != 0 || option > USHRT_MAX)
1064                                 goto out_invalid_value;
1065                         mnt->nfs_server.port = option;
1066                         break;
1067                 case Opt_rsize:
1068                         string = match_strdup(args);
1069                         if (string == NULL)
1070                                 goto out_nomem;
1071                         rc = strict_strtoul(string, 10, &option);
1072                         kfree(string);
1073                         if (rc != 0)
1074                                 goto out_invalid_value;
1075                         mnt->rsize = option;
1076                         break;
1077                 case Opt_wsize:
1078                         string = match_strdup(args);
1079                         if (string == NULL)
1080                                 goto out_nomem;
1081                         rc = strict_strtoul(string, 10, &option);
1082                         kfree(string);
1083                         if (rc != 0)
1084                                 goto out_invalid_value;
1085                         mnt->wsize = option;
1086                         break;
1087                 case Opt_bsize:
1088                         string = match_strdup(args);
1089                         if (string == NULL)
1090                                 goto out_nomem;
1091                         rc = strict_strtoul(string, 10, &option);
1092                         kfree(string);
1093                         if (rc != 0)
1094                                 goto out_invalid_value;
1095                         mnt->bsize = option;
1096                         break;
1097                 case Opt_timeo:
1098                         string = match_strdup(args);
1099                         if (string == NULL)
1100                                 goto out_nomem;
1101                         rc = strict_strtoul(string, 10, &option);
1102                         kfree(string);
1103                         if (rc != 0 || option == 0)
1104                                 goto out_invalid_value;
1105                         mnt->timeo = option;
1106                         break;
1107                 case Opt_retrans:
1108                         string = match_strdup(args);
1109                         if (string == NULL)
1110                                 goto out_nomem;
1111                         rc = strict_strtoul(string, 10, &option);
1112                         kfree(string);
1113                         if (rc != 0 || option == 0)
1114                                 goto out_invalid_value;
1115                         mnt->retrans = option;
1116                         break;
1117                 case Opt_acregmin:
1118                         string = match_strdup(args);
1119                         if (string == NULL)
1120                                 goto out_nomem;
1121                         rc = strict_strtoul(string, 10, &option);
1122                         kfree(string);
1123                         if (rc != 0)
1124                                 goto out_invalid_value;
1125                         mnt->acregmin = option;
1126                         break;
1127                 case Opt_acregmax:
1128                         string = match_strdup(args);
1129                         if (string == NULL)
1130                                 goto out_nomem;
1131                         rc = strict_strtoul(string, 10, &option);
1132                         kfree(string);
1133                         if (rc != 0)
1134                                 goto out_invalid_value;
1135                         mnt->acregmax = option;
1136                         break;
1137                 case Opt_acdirmin:
1138                         string = match_strdup(args);
1139                         if (string == NULL)
1140                                 goto out_nomem;
1141                         rc = strict_strtoul(string, 10, &option);
1142                         kfree(string);
1143                         if (rc != 0)
1144                                 goto out_invalid_value;
1145                         mnt->acdirmin = option;
1146                         break;
1147                 case Opt_acdirmax:
1148                         string = match_strdup(args);
1149                         if (string == NULL)
1150                                 goto out_nomem;
1151                         rc = strict_strtoul(string, 10, &option);
1152                         kfree(string);
1153                         if (rc != 0)
1154                                 goto out_invalid_value;
1155                         mnt->acdirmax = option;
1156                         break;
1157                 case Opt_actimeo:
1158                         string = match_strdup(args);
1159                         if (string == NULL)
1160                                 goto out_nomem;
1161                         rc = strict_strtoul(string, 10, &option);
1162                         kfree(string);
1163                         if (rc != 0)
1164                                 goto out_invalid_value;
1165                         mnt->acregmin = mnt->acregmax =
1166                         mnt->acdirmin = mnt->acdirmax = option;
1167                         break;
1168                 case Opt_namelen:
1169                         string = match_strdup(args);
1170                         if (string == NULL)
1171                                 goto out_nomem;
1172                         rc = strict_strtoul(string, 10, &option);
1173                         kfree(string);
1174                         if (rc != 0)
1175                                 goto out_invalid_value;
1176                         mnt->namlen = option;
1177                         break;
1178                 case Opt_mountport:
1179                         string = match_strdup(args);
1180                         if (string == NULL)
1181                                 goto out_nomem;
1182                         rc = strict_strtoul(string, 10, &option);
1183                         kfree(string);
1184                         if (rc != 0 || option > USHRT_MAX)
1185                                 goto out_invalid_value;
1186                         mnt->mount_server.port = option;
1187                         break;
1188                 case Opt_mountvers:
1189                         string = match_strdup(args);
1190                         if (string == NULL)
1191                                 goto out_nomem;
1192                         rc = strict_strtoul(string, 10, &option);
1193                         kfree(string);
1194                         if (rc != 0 ||
1195                             option < NFS_MNT_VERSION ||
1196                             option > NFS_MNT3_VERSION)
1197                                 goto out_invalid_value;
1198                         mnt->mount_server.version = option;
1199                         break;
1200                 case Opt_nfsvers:
1201                         string = match_strdup(args);
1202                         if (string == NULL)
1203                                 goto out_nomem;
1204                         rc = strict_strtoul(string, 10, &option);
1205                         kfree(string);
1206                         if (rc != 0)
1207                                 goto out_invalid_value;
1208                         switch (option) {
1209                         case NFS2_VERSION:
1210                                 mnt->flags &= ~NFS_MOUNT_VER3;
1211                                 mnt->version = 2;
1212                                 break;
1213                         case NFS3_VERSION:
1214                                 mnt->flags |= NFS_MOUNT_VER3;
1215                                 mnt->version = 3;
1216                                 break;
1217 #ifdef CONFIG_NFS_V4
1218                         case NFS4_VERSION:
1219                                 mnt->flags &= ~NFS_MOUNT_VER3;
1220                                 mnt->version = 4;
1221                                 break;
1222 #endif
1223                         default:
1224                                 goto out_invalid_value;
1225                         }
1226                         break;
1227                 case Opt_minorversion:
1228                         string = match_strdup(args);
1229                         if (string == NULL)
1230                                 goto out_nomem;
1231                         rc = strict_strtoul(string, 10, &option);
1232                         kfree(string);
1233                         if (rc != 0)
1234                                 goto out_invalid_value;
1235                         if (option > NFS4_MAX_MINOR_VERSION)
1236                                 goto out_invalid_value;
1237                         mnt->minorversion = option;
1238                         break;
1239
1240                 /*
1241                  * options that take text values
1242                  */
1243                 case Opt_sec:
1244                         string = match_strdup(args);
1245                         if (string == NULL)
1246                                 goto out_nomem;
1247                         rc = nfs_parse_security_flavors(string, mnt);
1248                         kfree(string);
1249                         if (!rc) {
1250                                 dfprintk(MOUNT, "NFS:   unrecognized "
1251                                                 "security flavor\n");
1252                                 return 0;
1253                         }
1254                         break;
1255                 case Opt_proto:
1256                         string = match_strdup(args);
1257                         if (string == NULL)
1258                                 goto out_nomem;
1259                         token = match_token(string,
1260                                             nfs_xprt_protocol_tokens, args);
1261
1262                         protofamily = AF_INET;
1263                         switch (token) {
1264                         case Opt_xprt_udp6:
1265                                 protofamily = AF_INET6;
1266                         case Opt_xprt_udp:
1267                                 mnt->flags &= ~NFS_MOUNT_TCP;
1268                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1269                                 kfree(string);
1270                                 break;
1271                         case Opt_xprt_tcp6:
1272                                 protofamily = AF_INET6;
1273                         case Opt_xprt_tcp:
1274                                 mnt->flags |= NFS_MOUNT_TCP;
1275                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1276                                 kfree(string);
1277                                 break;
1278                         case Opt_xprt_rdma:
1279                                 /* vector side protocols to TCP */
1280                                 mnt->flags |= NFS_MOUNT_TCP;
1281                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1282                                 xprt_load_transport(string);
1283                                 kfree(string);
1284                                 break;
1285                         default:
1286                                 dfprintk(MOUNT, "NFS:   unrecognized "
1287                                                 "transport protocol\n");
1288                                 kfree(string);
1289                                 return 0;
1290                         }
1291                         break;
1292                 case Opt_mountproto:
1293                         string = match_strdup(args);
1294                         if (string == NULL)
1295                                 goto out_nomem;
1296                         token = match_token(string,
1297                                             nfs_xprt_protocol_tokens, args);
1298                         kfree(string);
1299
1300                         mountfamily = AF_INET;
1301                         switch (token) {
1302                         case Opt_xprt_udp6:
1303                                 mountfamily = AF_INET6;
1304                         case Opt_xprt_udp:
1305                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1306                                 break;
1307                         case Opt_xprt_tcp6:
1308                                 mountfamily = AF_INET6;
1309                         case Opt_xprt_tcp:
1310                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1311                                 break;
1312                         case Opt_xprt_rdma: /* not used for side protocols */
1313                         default:
1314                                 dfprintk(MOUNT, "NFS:   unrecognized "
1315                                                 "transport protocol\n");
1316                                 return 0;
1317                         }
1318                         break;
1319                 case Opt_addr:
1320                         string = match_strdup(args);
1321                         if (string == NULL)
1322                                 goto out_nomem;
1323                         mnt->nfs_server.addrlen =
1324                                 rpc_pton(string, strlen(string),
1325                                         (struct sockaddr *)
1326                                         &mnt->nfs_server.address,
1327                                         sizeof(mnt->nfs_server.address));
1328                         kfree(string);
1329                         if (mnt->nfs_server.addrlen == 0)
1330                                 goto out_invalid_address;
1331                         break;
1332                 case Opt_clientaddr:
1333                         string = match_strdup(args);
1334                         if (string == NULL)
1335                                 goto out_nomem;
1336                         kfree(mnt->client_address);
1337                         mnt->client_address = string;
1338                         break;
1339                 case Opt_mounthost:
1340                         string = match_strdup(args);
1341                         if (string == NULL)
1342                                 goto out_nomem;
1343                         kfree(mnt->mount_server.hostname);
1344                         mnt->mount_server.hostname = string;
1345                         break;
1346                 case Opt_mountaddr:
1347                         string = match_strdup(args);
1348                         if (string == NULL)
1349                                 goto out_nomem;
1350                         mnt->mount_server.addrlen =
1351                                 rpc_pton(string, strlen(string),
1352                                         (struct sockaddr *)
1353                                         &mnt->mount_server.address,
1354                                         sizeof(mnt->mount_server.address));
1355                         kfree(string);
1356                         if (mnt->mount_server.addrlen == 0)
1357                                 goto out_invalid_address;
1358                         break;
1359                 case Opt_lookupcache:
1360                         string = match_strdup(args);
1361                         if (string == NULL)
1362                                 goto out_nomem;
1363                         token = match_token(string,
1364                                         nfs_lookupcache_tokens, args);
1365                         kfree(string);
1366                         switch (token) {
1367                                 case Opt_lookupcache_all:
1368                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1369                                         break;
1370                                 case Opt_lookupcache_positive:
1371                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1372                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1373                                         break;
1374                                 case Opt_lookupcache_none:
1375                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1376                                         break;
1377                                 default:
1378                                         dfprintk(MOUNT, "NFS:   invalid "
1379                                                         "lookupcache argument\n");
1380                                         return 0;
1381                         };
1382                         break;
1383                 case Opt_fscache_uniq:
1384                         string = match_strdup(args);
1385                         if (string == NULL)
1386                                 goto out_nomem;
1387                         kfree(mnt->fscache_uniq);
1388                         mnt->fscache_uniq = string;
1389                         mnt->options |= NFS_OPTION_FSCACHE;
1390                         break;
1391
1392                 /*
1393                  * Special options
1394                  */
1395                 case Opt_sloppy:
1396                         sloppy = 1;
1397                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1398                         break;
1399                 case Opt_userspace:
1400                 case Opt_deprecated:
1401                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1402                                         "'%s'\n", p);
1403                         break;
1404
1405                 default:
1406                         invalid_option = 1;
1407                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1408                                         "'%s'\n", p);
1409                 }
1410         }
1411
1412         if (!sloppy && invalid_option)
1413                 return 0;
1414
1415         /*
1416          * verify that any proto=/mountproto= options match the address
1417          * familiies in the addr=/mountaddr= options.
1418          */
1419         if (protofamily != AF_UNSPEC &&
1420             protofamily != mnt->nfs_server.address.ss_family)
1421                 goto out_proto_mismatch;
1422
1423         if (mountfamily != AF_UNSPEC) {
1424                 if (mnt->mount_server.addrlen) {
1425                         if (mountfamily != mnt->mount_server.address.ss_family)
1426                                 goto out_mountproto_mismatch;
1427                 } else {
1428                         if (mountfamily != mnt->nfs_server.address.ss_family)
1429                                 goto out_mountproto_mismatch;
1430                 }
1431         }
1432
1433         return 1;
1434
1435 out_mountproto_mismatch:
1436         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1437                          "option\n");
1438         return 0;
1439 out_proto_mismatch:
1440         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1441         return 0;
1442 out_invalid_address:
1443         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1444         return 0;
1445 out_invalid_value:
1446         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1447         return 0;
1448 out_nomem:
1449         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1450         return 0;
1451 out_security_failure:
1452         free_secdata(secdata);
1453         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1454         return 0;
1455 }
1456
1457 /*
1458  * Match the requested auth flavors with the list returned by
1459  * the server.  Returns zero and sets the mount's authentication
1460  * flavor on success; returns -EACCES if server does not support
1461  * the requested flavor.
1462  */
1463 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1464                              struct nfs_mount_request *request)
1465 {
1466         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1467
1468         /*
1469          * Certain releases of Linux's mountd return an empty
1470          * flavor list.  To prevent behavioral regression with
1471          * these servers (ie. rejecting mounts that used to
1472          * succeed), revert to pre-2.6.32 behavior (no checking)
1473          * if the returned flavor list is empty.
1474          */
1475         if (server_authlist_len == 0)
1476                 return 0;
1477
1478         /*
1479          * We avoid sophisticated negotiating here, as there are
1480          * plenty of cases where we can get it wrong, providing
1481          * either too little or too much security.
1482          *
1483          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1484          * flavor listed first.  However, some servers list
1485          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1486          * preferred default, in args->auth_flavors[0] if user
1487          * didn't specify sec= mount option.
1488          */
1489         for (i = 0; i < args->auth_flavor_len; i++)
1490                 for (j = 0; j < server_authlist_len; j++)
1491                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1492                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1493                                         request->auth_flavs[j]);
1494                                 args->auth_flavors[0] = request->auth_flavs[j];
1495                                 return 0;
1496                         }
1497
1498         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1499         nfs_umount(request);
1500         return -EACCES;
1501 }
1502
1503 /*
1504  * Use the remote server's MOUNT service to request the NFS file handle
1505  * corresponding to the provided path.
1506  */
1507 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1508                          struct nfs_fh *root_fh)
1509 {
1510         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1511         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1512         struct nfs_mount_request request = {
1513                 .sap            = (struct sockaddr *)
1514                                                 &args->mount_server.address,
1515                 .dirpath        = args->nfs_server.export_path,
1516                 .protocol       = args->mount_server.protocol,
1517                 .fh             = root_fh,
1518                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1519                 .auth_flav_len  = &server_authlist_len,
1520                 .auth_flavs     = server_authlist,
1521         };
1522         int status;
1523
1524         if (args->mount_server.version == 0) {
1525                 switch (args->version) {
1526                         default:
1527                                 args->mount_server.version = NFS_MNT3_VERSION;
1528                                 break;
1529                         case 2:
1530                                 args->mount_server.version = NFS_MNT_VERSION;
1531                 }
1532         }
1533         request.version = args->mount_server.version;
1534
1535         if (args->mount_server.hostname)
1536                 request.hostname = args->mount_server.hostname;
1537         else
1538                 request.hostname = args->nfs_server.hostname;
1539
1540         /*
1541          * Construct the mount server's address.
1542          */
1543         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1544                 memcpy(request.sap, &args->nfs_server.address,
1545                        args->nfs_server.addrlen);
1546                 args->mount_server.addrlen = args->nfs_server.addrlen;
1547         }
1548         request.salen = args->mount_server.addrlen;
1549         nfs_set_port(request.sap, &args->mount_server.port, 0);
1550
1551         /*
1552          * Now ask the mount server to map our export path
1553          * to a file handle.
1554          */
1555         status = nfs_mount(&request);
1556         if (status != 0) {
1557                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1558                                 request.hostname, status);
1559                 return status;
1560         }
1561
1562         /*
1563          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1564          */
1565         if (args->mount_server.version != NFS_MNT3_VERSION)
1566                 return 0;
1567         return nfs_walk_authlist(args, &request);
1568 }
1569
1570 static int nfs_parse_simple_hostname(const char *dev_name,
1571                                      char **hostname, size_t maxnamlen,
1572                                      char **export_path, size_t maxpathlen)
1573 {
1574         size_t len;
1575         char *colon, *comma;
1576
1577         colon = strchr(dev_name, ':');
1578         if (colon == NULL)
1579                 goto out_bad_devname;
1580
1581         len = colon - dev_name;
1582         if (len > maxnamlen)
1583                 goto out_hostname;
1584
1585         /* N.B. caller will free nfs_server.hostname in all cases */
1586         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1587         if (!*hostname)
1588                 goto out_nomem;
1589
1590         /* kill possible hostname list: not supported */
1591         comma = strchr(*hostname, ',');
1592         if (comma != NULL) {
1593                 if (comma == *hostname)
1594                         goto out_bad_devname;
1595                 *comma = '\0';
1596         }
1597
1598         colon++;
1599         len = strlen(colon);
1600         if (len > maxpathlen)
1601                 goto out_path;
1602         *export_path = kstrndup(colon, len, GFP_KERNEL);
1603         if (!*export_path)
1604                 goto out_nomem;
1605
1606         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1607         return 0;
1608
1609 out_bad_devname:
1610         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1611         return -EINVAL;
1612
1613 out_nomem:
1614         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1615         return -ENOMEM;
1616
1617 out_hostname:
1618         dfprintk(MOUNT, "NFS: server hostname too long\n");
1619         return -ENAMETOOLONG;
1620
1621 out_path:
1622         dfprintk(MOUNT, "NFS: export pathname too long\n");
1623         return -ENAMETOOLONG;
1624 }
1625
1626 /*
1627  * Hostname has square brackets around it because it contains one or
1628  * more colons.  We look for the first closing square bracket, and a
1629  * colon must follow it.
1630  */
1631 static int nfs_parse_protected_hostname(const char *dev_name,
1632                                         char **hostname, size_t maxnamlen,
1633                                         char **export_path, size_t maxpathlen)
1634 {
1635         size_t len;
1636         char *start, *end;
1637
1638         start = (char *)(dev_name + 1);
1639
1640         end = strchr(start, ']');
1641         if (end == NULL)
1642                 goto out_bad_devname;
1643         if (*(end + 1) != ':')
1644                 goto out_bad_devname;
1645
1646         len = end - start;
1647         if (len > maxnamlen)
1648                 goto out_hostname;
1649
1650         /* N.B. caller will free nfs_server.hostname in all cases */
1651         *hostname = kstrndup(start, len, GFP_KERNEL);
1652         if (*hostname == NULL)
1653                 goto out_nomem;
1654
1655         end += 2;
1656         len = strlen(end);
1657         if (len > maxpathlen)
1658                 goto out_path;
1659         *export_path = kstrndup(end, len, GFP_KERNEL);
1660         if (!*export_path)
1661                 goto out_nomem;
1662
1663         return 0;
1664
1665 out_bad_devname:
1666         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1667         return -EINVAL;
1668
1669 out_nomem:
1670         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1671         return -ENOMEM;
1672
1673 out_hostname:
1674         dfprintk(MOUNT, "NFS: server hostname too long\n");
1675         return -ENAMETOOLONG;
1676
1677 out_path:
1678         dfprintk(MOUNT, "NFS: export pathname too long\n");
1679         return -ENAMETOOLONG;
1680 }
1681
1682 /*
1683  * Split "dev_name" into "hostname:export_path".
1684  *
1685  * The leftmost colon demarks the split between the server's hostname
1686  * and the export path.  If the hostname starts with a left square
1687  * bracket, then it may contain colons.
1688  *
1689  * Note: caller frees hostname and export path, even on error.
1690  */
1691 static int nfs_parse_devname(const char *dev_name,
1692                              char **hostname, size_t maxnamlen,
1693                              char **export_path, size_t maxpathlen)
1694 {
1695         if (*dev_name == '[')
1696                 return nfs_parse_protected_hostname(dev_name,
1697                                                     hostname, maxnamlen,
1698                                                     export_path, maxpathlen);
1699
1700         return nfs_parse_simple_hostname(dev_name,
1701                                          hostname, maxnamlen,
1702                                          export_path, maxpathlen);
1703 }
1704
1705 /*
1706  * Validate the NFS2/NFS3 mount data
1707  * - fills in the mount root filehandle
1708  *
1709  * For option strings, user space handles the following behaviors:
1710  *
1711  * + DNS: mapping server host name to IP address ("addr=" option)
1712  *
1713  * + failure mode: how to behave if a mount request can't be handled
1714  *   immediately ("fg/bg" option)
1715  *
1716  * + retry: how often to retry a mount request ("retry=" option)
1717  *
1718  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1719  *   mountproto=tcp after mountproto=udp, and so on
1720  */
1721 static int nfs_validate_mount_data(void *options,
1722                                    struct nfs_parsed_mount_data *args,
1723                                    struct nfs_fh *mntfh,
1724                                    const char *dev_name)
1725 {
1726         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1727         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1728
1729         if (data == NULL)
1730                 goto out_no_data;
1731
1732         switch (data->version) {
1733         case 1:
1734                 data->namlen = 0;
1735         case 2:
1736                 data->bsize = 0;
1737         case 3:
1738                 if (data->flags & NFS_MOUNT_VER3)
1739                         goto out_no_v3;
1740                 data->root.size = NFS2_FHSIZE;
1741                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1742         case 4:
1743                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1744                         goto out_no_sec;
1745         case 5:
1746                 memset(data->context, 0, sizeof(data->context));
1747         case 6:
1748                 if (data->flags & NFS_MOUNT_VER3) {
1749                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1750                                 goto out_invalid_fh;
1751                         mntfh->size = data->root.size;
1752                         args->version = 3;
1753                 } else {
1754                         mntfh->size = NFS2_FHSIZE;
1755                         args->version = 2;
1756                 }
1757
1758
1759                 memcpy(mntfh->data, data->root.data, mntfh->size);
1760                 if (mntfh->size < sizeof(mntfh->data))
1761                         memset(mntfh->data + mntfh->size, 0,
1762                                sizeof(mntfh->data) - mntfh->size);
1763
1764                 /*
1765                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1766                  * can deal with.
1767                  */
1768                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1769                 args->rsize             = data->rsize;
1770                 args->wsize             = data->wsize;
1771                 args->timeo             = data->timeo;
1772                 args->retrans           = data->retrans;
1773                 args->acregmin          = data->acregmin;
1774                 args->acregmax          = data->acregmax;
1775                 args->acdirmin          = data->acdirmin;
1776                 args->acdirmax          = data->acdirmax;
1777
1778                 memcpy(sap, &data->addr, sizeof(data->addr));
1779                 args->nfs_server.addrlen = sizeof(data->addr);
1780                 if (!nfs_verify_server_address(sap))
1781                         goto out_no_address;
1782
1783                 if (!(data->flags & NFS_MOUNT_TCP))
1784                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1785                 /* N.B. caller will free nfs_server.hostname in all cases */
1786                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1787                 args->namlen            = data->namlen;
1788                 args->bsize             = data->bsize;
1789
1790                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1791                         args->auth_flavors[0] = data->pseudoflavor;
1792                 if (!args->nfs_server.hostname)
1793                         goto out_nomem;
1794
1795                 /*
1796                  * The legacy version 6 binary mount data from userspace has a
1797                  * field used only to transport selinux information into the
1798                  * the kernel.  To continue to support that functionality we
1799                  * have a touch of selinux knowledge here in the NFS code. The
1800                  * userspace code converted context=blah to just blah so we are
1801                  * converting back to the full string selinux understands.
1802                  */
1803                 if (data->context[0]){
1804 #ifdef CONFIG_SECURITY_SELINUX
1805                         int rc;
1806                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1807                         if (!opts_str)
1808                                 return -ENOMEM;
1809                         strcpy(opts_str, "context=");
1810                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1811                         strcat(opts_str, &data->context[0]);
1812                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1813                         kfree(opts_str);
1814                         if (rc)
1815                                 return rc;
1816 #else
1817                         return -EINVAL;
1818 #endif
1819                 }
1820
1821                 break;
1822         default: {
1823                 int status;
1824
1825                 if (nfs_parse_mount_options((char *)options, args) == 0)
1826                         return -EINVAL;
1827
1828                 if (!nfs_verify_server_address(sap))
1829                         goto out_no_address;
1830
1831                 if (args->version == 4)
1832 #ifdef CONFIG_NFS_V4
1833                         return nfs4_validate_text_mount_data(options,
1834                                                              args, dev_name);
1835 #else
1836                         goto out_v4_not_compiled;
1837 #endif
1838
1839                 nfs_set_port(sap, &args->nfs_server.port, 0);
1840
1841                 nfs_set_mount_transport_protocol(args);
1842
1843                 status = nfs_parse_devname(dev_name,
1844                                            &args->nfs_server.hostname,
1845                                            PAGE_SIZE,
1846                                            &args->nfs_server.export_path,
1847                                            NFS_MAXPATHLEN);
1848                 if (!status)
1849                         status = nfs_try_mount(args, mntfh);
1850
1851                 kfree(args->nfs_server.export_path);
1852                 args->nfs_server.export_path = NULL;
1853
1854                 if (status)
1855                         return status;
1856
1857                 break;
1858                 }
1859         }
1860
1861 #ifndef CONFIG_NFS_V3
1862         if (args->version == 3)
1863                 goto out_v3_not_compiled;
1864 #endif /* !CONFIG_NFS_V3 */
1865
1866         return 0;
1867
1868 out_no_data:
1869         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1870         return -EINVAL;
1871
1872 out_no_v3:
1873         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1874                  data->version);
1875         return -EINVAL;
1876
1877 out_no_sec:
1878         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1879         return -EINVAL;
1880
1881 #ifndef CONFIG_NFS_V3
1882 out_v3_not_compiled:
1883         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1884         return -EPROTONOSUPPORT;
1885 #endif /* !CONFIG_NFS_V3 */
1886
1887 #ifndef CONFIG_NFS_V4
1888 out_v4_not_compiled:
1889         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1890         return -EPROTONOSUPPORT;
1891 #endif /* !CONFIG_NFS_V4 */
1892
1893 out_nomem:
1894         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1895         return -ENOMEM;
1896
1897 out_no_address:
1898         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1899         return -EINVAL;
1900
1901 out_invalid_fh:
1902         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1903         return -EINVAL;
1904 }
1905
1906 static int
1907 nfs_compare_remount_data(struct nfs_server *nfss,
1908                          struct nfs_parsed_mount_data *data)
1909 {
1910         if (data->flags != nfss->flags ||
1911             data->rsize != nfss->rsize ||
1912             data->wsize != nfss->wsize ||
1913             data->retrans != nfss->client->cl_timeout->to_retries ||
1914             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1915             data->acregmin != nfss->acregmin / HZ ||
1916             data->acregmax != nfss->acregmax / HZ ||
1917             data->acdirmin != nfss->acdirmin / HZ ||
1918             data->acdirmax != nfss->acdirmax / HZ ||
1919             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1920             data->nfs_server.port != nfss->port ||
1921             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1922             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1923                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1924                 return -EINVAL;
1925
1926         return 0;
1927 }
1928
1929 static int
1930 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1931 {
1932         int error;
1933         struct nfs_server *nfss = sb->s_fs_info;
1934         struct nfs_parsed_mount_data *data;
1935         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1936         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1937         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1938
1939         /*
1940          * Userspace mount programs that send binary options generally send
1941          * them populated with default values. We have no way to know which
1942          * ones were explicitly specified. Fall back to legacy behavior and
1943          * just return success.
1944          */
1945         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1946             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1947                                            options->version <= 6))))
1948                 return 0;
1949
1950         data = kzalloc(sizeof(*data), GFP_KERNEL);
1951         if (data == NULL)
1952                 return -ENOMEM;
1953
1954         /* fill out struct with values from existing mount */
1955         data->flags = nfss->flags;
1956         data->rsize = nfss->rsize;
1957         data->wsize = nfss->wsize;
1958         data->retrans = nfss->client->cl_timeout->to_retries;
1959         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1960         data->acregmin = nfss->acregmin / HZ;
1961         data->acregmax = nfss->acregmax / HZ;
1962         data->acdirmin = nfss->acdirmin / HZ;
1963         data->acdirmax = nfss->acdirmax / HZ;
1964         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1965         data->nfs_server.port = nfss->port;
1966         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1967         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1968                 data->nfs_server.addrlen);
1969
1970         /* overwrite those values with any that were specified */
1971         error = nfs_parse_mount_options((char *)options, data);
1972         if (error < 0)
1973                 goto out;
1974
1975         /* compare new mount options with old ones */
1976         error = nfs_compare_remount_data(nfss, data);
1977 out:
1978         kfree(data);
1979         return error;
1980 }
1981
1982 /*
1983  * Initialise the common bits of the superblock
1984  */
1985 static inline void nfs_initialise_sb(struct super_block *sb)
1986 {
1987         struct nfs_server *server = NFS_SB(sb);
1988
1989         sb->s_magic = NFS_SUPER_MAGIC;
1990
1991         /* We probably want something more informative here */
1992         snprintf(sb->s_id, sizeof(sb->s_id),
1993                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1994
1995         if (sb->s_blocksize == 0)
1996                 sb->s_blocksize = nfs_block_bits(server->wsize,
1997                                                  &sb->s_blocksize_bits);
1998
1999         if (server->flags & NFS_MOUNT_NOAC)
2000                 sb->s_flags |= MS_SYNCHRONOUS;
2001
2002         sb->s_bdi = &server->backing_dev_info;
2003
2004         nfs_super_set_maxbytes(sb, server->maxfilesize);
2005 }
2006
2007 /*
2008  * Finish setting up an NFS2/3 superblock
2009  */
2010 static void nfs_fill_super(struct super_block *sb,
2011                            struct nfs_parsed_mount_data *data)
2012 {
2013         struct nfs_server *server = NFS_SB(sb);
2014
2015         sb->s_blocksize_bits = 0;
2016         sb->s_blocksize = 0;
2017         if (data->bsize)
2018                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2019
2020         if (server->nfs_client->rpc_ops->version == 3) {
2021                 /* The VFS shouldn't apply the umask to mode bits. We will do
2022                  * so ourselves when necessary.
2023                  */
2024                 sb->s_flags |= MS_POSIXACL;
2025                 sb->s_time_gran = 1;
2026         }
2027
2028         sb->s_op = &nfs_sops;
2029         nfs_initialise_sb(sb);
2030 }
2031
2032 /*
2033  * Finish setting up a cloned NFS2/3 superblock
2034  */
2035 static void nfs_clone_super(struct super_block *sb,
2036                             const struct super_block *old_sb)
2037 {
2038         struct nfs_server *server = NFS_SB(sb);
2039
2040         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2041         sb->s_blocksize = old_sb->s_blocksize;
2042         sb->s_maxbytes = old_sb->s_maxbytes;
2043
2044         if (server->nfs_client->rpc_ops->version == 3) {
2045                 /* The VFS shouldn't apply the umask to mode bits. We will do
2046                  * so ourselves when necessary.
2047                  */
2048                 sb->s_flags |= MS_POSIXACL;
2049                 sb->s_time_gran = 1;
2050         }
2051
2052         sb->s_op = old_sb->s_op;
2053         nfs_initialise_sb(sb);
2054 }
2055
2056 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2057 {
2058         const struct nfs_server *a = s->s_fs_info;
2059         const struct rpc_clnt *clnt_a = a->client;
2060         const struct rpc_clnt *clnt_b = b->client;
2061
2062         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2063                 goto Ebusy;
2064         if (a->nfs_client != b->nfs_client)
2065                 goto Ebusy;
2066         if (a->flags != b->flags)
2067                 goto Ebusy;
2068         if (a->wsize != b->wsize)
2069                 goto Ebusy;
2070         if (a->rsize != b->rsize)
2071                 goto Ebusy;
2072         if (a->acregmin != b->acregmin)
2073                 goto Ebusy;
2074         if (a->acregmax != b->acregmax)
2075                 goto Ebusy;
2076         if (a->acdirmin != b->acdirmin)
2077                 goto Ebusy;
2078         if (a->acdirmax != b->acdirmax)
2079                 goto Ebusy;
2080         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2081                 goto Ebusy;
2082         return 1;
2083 Ebusy:
2084         return 0;
2085 }
2086
2087 struct nfs_sb_mountdata {
2088         struct nfs_server *server;
2089         int mntflags;
2090 };
2091
2092 static int nfs_set_super(struct super_block *s, void *data)
2093 {
2094         struct nfs_sb_mountdata *sb_mntdata = data;
2095         struct nfs_server *server = sb_mntdata->server;
2096         int ret;
2097
2098         s->s_flags = sb_mntdata->mntflags;
2099         s->s_fs_info = server;
2100         ret = set_anon_super(s, server);
2101         if (ret == 0)
2102                 server->s_dev = s->s_dev;
2103         return ret;
2104 }
2105
2106 static int nfs_compare_super_address(struct nfs_server *server1,
2107                                      struct nfs_server *server2)
2108 {
2109         struct sockaddr *sap1, *sap2;
2110
2111         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2112         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2113
2114         if (sap1->sa_family != sap2->sa_family)
2115                 return 0;
2116
2117         switch (sap1->sa_family) {
2118         case AF_INET: {
2119                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2120                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2121                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2122                         return 0;
2123                 if (sin1->sin_port != sin2->sin_port)
2124                         return 0;
2125                 break;
2126         }
2127         case AF_INET6: {
2128                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2129                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2130                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2131                         return 0;
2132                 if (sin1->sin6_port != sin2->sin6_port)
2133                         return 0;
2134                 break;
2135         }
2136         default:
2137                 return 0;
2138         }
2139
2140         return 1;
2141 }
2142
2143 static int nfs_compare_super(struct super_block *sb, void *data)
2144 {
2145         struct nfs_sb_mountdata *sb_mntdata = data;
2146         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2147         int mntflags = sb_mntdata->mntflags;
2148
2149         if (!nfs_compare_super_address(old, server))
2150                 return 0;
2151         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2152         if (old->flags & NFS_MOUNT_UNSHARED)
2153                 return 0;
2154         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2155                 return 0;
2156         return nfs_compare_mount_options(sb, server, mntflags);
2157 }
2158
2159 static int nfs_bdi_register(struct nfs_server *server)
2160 {
2161         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2162 }
2163
2164 static int nfs_get_sb(struct file_system_type *fs_type,
2165         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2166 {
2167         struct nfs_server *server = NULL;
2168         struct super_block *s;
2169         struct nfs_parsed_mount_data *data;
2170         struct nfs_fh *mntfh;
2171         struct dentry *mntroot;
2172         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2173         struct nfs_sb_mountdata sb_mntdata = {
2174                 .mntflags = flags,
2175         };
2176         int error = -ENOMEM;
2177
2178         data = nfs_alloc_parsed_mount_data(3);
2179         mntfh = nfs_alloc_fhandle();
2180         if (data == NULL || mntfh == NULL)
2181                 goto out_free_fh;
2182
2183         security_init_mnt_opts(&data->lsm_opts);
2184
2185         /* Validate the mount data */
2186         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2187         if (error < 0)
2188                 goto out;
2189
2190 #ifdef CONFIG_NFS_V4
2191         if (data->version == 4) {
2192                 error = nfs4_try_mount(flags, dev_name, data, mnt);
2193                 kfree(data->client_address);
2194                 kfree(data->nfs_server.export_path);
2195                 goto out;
2196         }
2197 #endif  /* CONFIG_NFS_V4 */
2198
2199         /* Get a volume representation */
2200         server = nfs_create_server(data, mntfh);
2201         if (IS_ERR(server)) {
2202                 error = PTR_ERR(server);
2203                 goto out;
2204         }
2205         sb_mntdata.server = server;
2206
2207         if (server->flags & NFS_MOUNT_UNSHARED)
2208                 compare_super = NULL;
2209
2210         /* Get a superblock - note that we may end up sharing one that already exists */
2211         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2212         if (IS_ERR(s)) {
2213                 error = PTR_ERR(s);
2214                 goto out_err_nosb;
2215         }
2216
2217         if (s->s_fs_info != server) {
2218                 nfs_free_server(server);
2219                 server = NULL;
2220         } else {
2221                 error = nfs_bdi_register(server);
2222                 if (error)
2223                         goto error_splat_bdi;
2224         }
2225
2226         if (!s->s_root) {
2227                 /* initial superblock/root creation */
2228                 nfs_fill_super(s, data);
2229                 nfs_fscache_get_super_cookie(
2230                         s, data ? data->fscache_uniq : NULL, NULL);
2231         }
2232
2233         mntroot = nfs_get_root(s, mntfh);
2234         if (IS_ERR(mntroot)) {
2235                 error = PTR_ERR(mntroot);
2236                 goto error_splat_super;
2237         }
2238
2239         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2240         if (error)
2241                 goto error_splat_root;
2242
2243         s->s_flags |= MS_ACTIVE;
2244         mnt->mnt_sb = s;
2245         mnt->mnt_root = mntroot;
2246         error = 0;
2247
2248 out:
2249         kfree(data->nfs_server.hostname);
2250         kfree(data->mount_server.hostname);
2251         kfree(data->fscache_uniq);
2252         security_free_mnt_opts(&data->lsm_opts);
2253 out_free_fh:
2254         nfs_free_fhandle(mntfh);
2255         kfree(data);
2256         return error;
2257
2258 out_err_nosb:
2259         nfs_free_server(server);
2260         goto out;
2261
2262 error_splat_root:
2263         dput(mntroot);
2264 error_splat_super:
2265         if (server && !s->s_root)
2266                 bdi_unregister(&server->backing_dev_info);
2267 error_splat_bdi:
2268         deactivate_locked_super(s);
2269         goto out;
2270 }
2271
2272 /*
2273  * Ensure that we unregister the bdi before kill_anon_super
2274  * releases the device name
2275  */
2276 static void nfs_put_super(struct super_block *s)
2277 {
2278         struct nfs_server *server = NFS_SB(s);
2279
2280         bdi_unregister(&server->backing_dev_info);
2281 }
2282
2283 /*
2284  * Destroy an NFS2/3 superblock
2285  */
2286 static void nfs_kill_super(struct super_block *s)
2287 {
2288         struct nfs_server *server = NFS_SB(s);
2289
2290         kill_anon_super(s);
2291         nfs_fscache_release_super_cookie(s);
2292         nfs_free_server(server);
2293 }
2294
2295 /*
2296  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2297  */
2298 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
2299                            const char *dev_name, void *raw_data,
2300                            struct vfsmount *mnt)
2301 {
2302         struct nfs_clone_mount *data = raw_data;
2303         struct super_block *s;
2304         struct nfs_server *server;
2305         struct dentry *mntroot;
2306         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2307         struct nfs_sb_mountdata sb_mntdata = {
2308                 .mntflags = flags,
2309         };
2310         int error;
2311
2312         dprintk("--> nfs_xdev_get_sb()\n");
2313
2314         /* create a new volume representation */
2315         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2316         if (IS_ERR(server)) {
2317                 error = PTR_ERR(server);
2318                 goto out_err_noserver;
2319         }
2320         sb_mntdata.server = server;
2321
2322         if (server->flags & NFS_MOUNT_UNSHARED)
2323                 compare_super = NULL;
2324
2325         /* Get a superblock - note that we may end up sharing one that already exists */
2326         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2327         if (IS_ERR(s)) {
2328                 error = PTR_ERR(s);
2329                 goto out_err_nosb;
2330         }
2331
2332         if (s->s_fs_info != server) {
2333                 nfs_free_server(server);
2334                 server = NULL;
2335         } else {
2336                 error = nfs_bdi_register(server);
2337                 if (error)
2338                         goto error_splat_bdi;
2339         }
2340
2341         if (!s->s_root) {
2342                 /* initial superblock/root creation */
2343                 nfs_clone_super(s, data->sb);
2344                 nfs_fscache_get_super_cookie(s, NULL, data);
2345         }
2346
2347         mntroot = nfs_get_root(s, data->fh);
2348         if (IS_ERR(mntroot)) {
2349                 error = PTR_ERR(mntroot);
2350                 goto error_splat_super;
2351         }
2352         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2353                 dput(mntroot);
2354                 error = -ESTALE;
2355                 goto error_splat_super;
2356         }
2357
2358         s->s_flags |= MS_ACTIVE;
2359         mnt->mnt_sb = s;
2360         mnt->mnt_root = mntroot;
2361
2362         /* clone any lsm security options from the parent to the new sb */
2363         security_sb_clone_mnt_opts(data->sb, s);
2364
2365         dprintk("<-- nfs_xdev_get_sb() = 0\n");
2366         return 0;
2367
2368 out_err_nosb:
2369         nfs_free_server(server);
2370 out_err_noserver:
2371         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
2372         return error;
2373
2374 error_splat_super:
2375         if (server && !s->s_root)
2376                 bdi_unregister(&server->backing_dev_info);
2377 error_splat_bdi:
2378         deactivate_locked_super(s);
2379         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
2380         return error;
2381 }
2382
2383 #ifdef CONFIG_NFS_V4
2384
2385 /*
2386  * Finish setting up a cloned NFS4 superblock
2387  */
2388 static void nfs4_clone_super(struct super_block *sb,
2389                             const struct super_block *old_sb)
2390 {
2391         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2392         sb->s_blocksize = old_sb->s_blocksize;
2393         sb->s_maxbytes = old_sb->s_maxbytes;
2394         sb->s_time_gran = 1;
2395         sb->s_op = old_sb->s_op;
2396         nfs_initialise_sb(sb);
2397 }
2398
2399 /*
2400  * Set up an NFS4 superblock
2401  */
2402 static void nfs4_fill_super(struct super_block *sb)
2403 {
2404         sb->s_time_gran = 1;
2405         sb->s_op = &nfs4_sops;
2406         nfs_initialise_sb(sb);
2407 }
2408
2409 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2410 {
2411         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3);
2412 }
2413
2414 static int nfs4_validate_text_mount_data(void *options,
2415                                          struct nfs_parsed_mount_data *args,
2416                                          const char *dev_name)
2417 {
2418         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2419
2420         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2421
2422         nfs_validate_transport_protocol(args);
2423
2424         nfs4_validate_mount_flags(args);
2425
2426         if (args->version != 4) {
2427                 dfprintk(MOUNT,
2428                          "NFS4: Illegal mount version\n");
2429                 return -EINVAL;
2430         }
2431
2432         if (args->auth_flavor_len > 1) {
2433                 dfprintk(MOUNT,
2434                          "NFS4: Too many RPC auth flavours specified\n");
2435                 return -EINVAL;
2436         }
2437
2438         if (args->client_address == NULL) {
2439                 dfprintk(MOUNT,
2440                          "NFS4: mount program didn't pass callback address\n");
2441                 return -EINVAL;
2442         }
2443
2444         return nfs_parse_devname(dev_name,
2445                                    &args->nfs_server.hostname,
2446                                    NFS4_MAXNAMLEN,
2447                                    &args->nfs_server.export_path,
2448                                    NFS4_MAXPATHLEN);
2449 }
2450
2451 /*
2452  * Validate NFSv4 mount options
2453  */
2454 static int nfs4_validate_mount_data(void *options,
2455                                     struct nfs_parsed_mount_data *args,
2456                                     const char *dev_name)
2457 {
2458         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2459         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2460         char *c;
2461
2462         if (data == NULL)
2463                 goto out_no_data;
2464
2465         switch (data->version) {
2466         case 1:
2467                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2468                         goto out_no_address;
2469                 if (data->host_addrlen == 0)
2470                         goto out_no_address;
2471                 args->nfs_server.addrlen = data->host_addrlen;
2472                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2473                         return -EFAULT;
2474                 if (!nfs_verify_server_address(sap))
2475                         goto out_no_address;
2476
2477                 if (data->auth_flavourlen) {
2478                         if (data->auth_flavourlen > 1)
2479                                 goto out_inval_auth;
2480                         if (copy_from_user(&args->auth_flavors[0],
2481                                            data->auth_flavours,
2482                                            sizeof(args->auth_flavors[0])))
2483                                 return -EFAULT;
2484                 }
2485
2486                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2487                 if (IS_ERR(c))
2488                         return PTR_ERR(c);
2489                 args->nfs_server.hostname = c;
2490
2491                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2492                 if (IS_ERR(c))
2493                         return PTR_ERR(c);
2494                 args->nfs_server.export_path = c;
2495                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2496
2497                 c = strndup_user(data->client_addr.data, 16);
2498                 if (IS_ERR(c))
2499                         return PTR_ERR(c);
2500                 args->client_address = c;
2501
2502                 /*
2503                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2504                  * can deal with.
2505                  */
2506
2507                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2508                 args->rsize     = data->rsize;
2509                 args->wsize     = data->wsize;
2510                 args->timeo     = data->timeo;
2511                 args->retrans   = data->retrans;
2512                 args->acregmin  = data->acregmin;
2513                 args->acregmax  = data->acregmax;
2514                 args->acdirmin  = data->acdirmin;
2515                 args->acdirmax  = data->acdirmax;
2516                 args->nfs_server.protocol = data->proto;
2517                 nfs_validate_transport_protocol(args);
2518
2519                 break;
2520         default:
2521                 if (nfs_parse_mount_options((char *)options, args) == 0)
2522                         return -EINVAL;
2523
2524                 if (!nfs_verify_server_address(sap))
2525                         return -EINVAL;
2526
2527                 return nfs4_validate_text_mount_data(options, args, dev_name);
2528         }
2529
2530         return 0;
2531
2532 out_no_data:
2533         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2534         return -EINVAL;
2535
2536 out_inval_auth:
2537         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2538                  data->auth_flavourlen);
2539         return -EINVAL;
2540
2541 out_no_address:
2542         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2543         return -EINVAL;
2544 }
2545
2546 /*
2547  * Get the superblock for the NFS4 root partition
2548  */
2549 static int nfs4_remote_get_sb(struct file_system_type *fs_type,
2550         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2551 {
2552         struct nfs_parsed_mount_data *data = raw_data;
2553         struct super_block *s;
2554         struct nfs_server *server;
2555         struct nfs_fh *mntfh;
2556         struct dentry *mntroot;
2557         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2558         struct nfs_sb_mountdata sb_mntdata = {
2559                 .mntflags = flags,
2560         };
2561         int error = -ENOMEM;
2562
2563         mntfh = nfs_alloc_fhandle();
2564         if (data == NULL || mntfh == NULL)
2565                 goto out_free_fh;
2566
2567         security_init_mnt_opts(&data->lsm_opts);
2568
2569         /* Get a volume representation */
2570         server = nfs4_create_server(data, mntfh);
2571         if (IS_ERR(server)) {
2572                 error = PTR_ERR(server);
2573                 goto out;
2574         }
2575         sb_mntdata.server = server;
2576
2577         if (server->flags & NFS4_MOUNT_UNSHARED)
2578                 compare_super = NULL;
2579
2580         /* Get a superblock - note that we may end up sharing one that already exists */
2581         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2582         if (IS_ERR(s)) {
2583                 error = PTR_ERR(s);
2584                 goto out_free;
2585         }
2586
2587         if (s->s_fs_info != server) {
2588                 nfs_free_server(server);
2589                 server = NULL;
2590         } else {
2591                 error = nfs_bdi_register(server);
2592                 if (error)
2593                         goto error_splat_bdi;
2594         }
2595
2596         if (!s->s_root) {
2597                 /* initial superblock/root creation */
2598                 nfs4_fill_super(s);
2599                 nfs_fscache_get_super_cookie(
2600                         s, data ? data->fscache_uniq : NULL, NULL);
2601         }
2602
2603         mntroot = nfs4_get_root(s, mntfh);
2604         if (IS_ERR(mntroot)) {
2605                 error = PTR_ERR(mntroot);
2606                 goto error_splat_super;
2607         }
2608
2609         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2610         if (error)
2611                 goto error_splat_root;
2612
2613         s->s_flags |= MS_ACTIVE;
2614         mnt->mnt_sb = s;
2615         mnt->mnt_root = mntroot;
2616         error = 0;
2617
2618 out:
2619         security_free_mnt_opts(&data->lsm_opts);
2620 out_free_fh:
2621         nfs_free_fhandle(mntfh);
2622         return error;
2623
2624 out_free:
2625         nfs_free_server(server);
2626         goto out;
2627
2628 error_splat_root:
2629         dput(mntroot);
2630 error_splat_super:
2631         if (server && !s->s_root)
2632                 bdi_unregister(&server->backing_dev_info);
2633 error_splat_bdi:
2634         deactivate_locked_super(s);
2635         goto out;
2636 }
2637
2638 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2639                 int flags, void *data, const char *hostname)
2640 {
2641         struct vfsmount *root_mnt;
2642         char *root_devname;
2643         size_t len;
2644
2645         len = strlen(hostname) + 3;
2646         root_devname = kmalloc(len, GFP_KERNEL);
2647         if (root_devname == NULL)
2648                 return ERR_PTR(-ENOMEM);
2649         snprintf(root_devname, len, "%s:/", hostname);
2650         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2651         kfree(root_devname);
2652         return root_mnt;
2653 }
2654
2655 static void nfs_fix_devname(const struct path *path, struct vfsmount *mnt)
2656 {
2657         char *page = (char *) __get_free_page(GFP_KERNEL);
2658         char *devname, *tmp;
2659
2660         if (page == NULL)
2661                 return;
2662         devname = nfs_path(path->mnt->mnt_devname,
2663                         path->mnt->mnt_root, path->dentry,
2664                         page, PAGE_SIZE);
2665         if (IS_ERR(devname))
2666                 goto out_freepage;
2667         tmp = kstrdup(devname, GFP_KERNEL);
2668         if (tmp == NULL)
2669                 goto out_freepage;
2670         kfree(mnt->mnt_devname);
2671         mnt->mnt_devname = tmp;
2672 out_freepage:
2673         free_page((unsigned long)page);
2674 }
2675
2676 struct nfs_referral_count {
2677         struct list_head list;
2678         const struct task_struct *task;
2679         unsigned int referral_count;
2680 };
2681
2682 static LIST_HEAD(nfs_referral_count_list);
2683 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2684
2685 static struct nfs_referral_count *nfs_find_referral_count(void)
2686 {
2687         struct nfs_referral_count *p;
2688
2689         list_for_each_entry(p, &nfs_referral_count_list, list) {
2690                 if (p->task == current)
2691                         return p;
2692         }
2693         return NULL;
2694 }
2695
2696 #define NFS_MAX_NESTED_REFERRALS 2
2697
2698 static int nfs_referral_loop_protect(void)
2699 {
2700         struct nfs_referral_count *p, *new;
2701         int ret = -ENOMEM;
2702
2703         new = kmalloc(sizeof(*new), GFP_KERNEL);
2704         if (!new)
2705                 goto out;
2706         new->task = current;
2707         new->referral_count = 1;
2708
2709         ret = 0;
2710         spin_lock(&nfs_referral_count_list_lock);
2711         p = nfs_find_referral_count();
2712         if (p != NULL) {
2713                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2714                         ret = -ELOOP;
2715                 else
2716                         p->referral_count++;
2717         } else {
2718                 list_add(&new->list, &nfs_referral_count_list);
2719                 new = NULL;
2720         }
2721         spin_unlock(&nfs_referral_count_list_lock);
2722         kfree(new);
2723 out:
2724         return ret;
2725 }
2726
2727 static void nfs_referral_loop_unprotect(void)
2728 {
2729         struct nfs_referral_count *p;
2730
2731         spin_lock(&nfs_referral_count_list_lock);
2732         p = nfs_find_referral_count();
2733         p->referral_count--;
2734         if (p->referral_count == 0)
2735                 list_del(&p->list);
2736         else
2737                 p = NULL;
2738         spin_unlock(&nfs_referral_count_list_lock);
2739         kfree(p);
2740 }
2741
2742 static int nfs_follow_remote_path(struct vfsmount *root_mnt,
2743                 const char *export_path, struct vfsmount *mnt_target)
2744 {
2745         struct nameidata *nd = NULL;
2746         struct mnt_namespace *ns_private;
2747         struct super_block *s;
2748         int ret;
2749
2750         nd = kmalloc(sizeof(*nd), GFP_KERNEL);
2751         if (nd == NULL)
2752                 return -ENOMEM;
2753
2754         ns_private = create_mnt_ns(root_mnt);
2755         ret = PTR_ERR(ns_private);
2756         if (IS_ERR(ns_private))
2757                 goto out_mntput;
2758
2759         ret = nfs_referral_loop_protect();
2760         if (ret != 0)
2761                 goto out_put_mnt_ns;
2762
2763         ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
2764                         export_path, LOOKUP_FOLLOW, nd);
2765
2766         nfs_referral_loop_unprotect();
2767         put_mnt_ns(ns_private);
2768
2769         if (ret != 0)
2770                 goto out_err;
2771
2772         s = nd->path.mnt->mnt_sb;
2773         atomic_inc(&s->s_active);
2774         mnt_target->mnt_sb = s;
2775         mnt_target->mnt_root = dget(nd->path.dentry);
2776
2777         /* Correct the device pathname */
2778         nfs_fix_devname(&nd->path, mnt_target);
2779
2780         path_put(&nd->path);
2781         kfree(nd);
2782         down_write(&s->s_umount);
2783         return 0;
2784 out_put_mnt_ns:
2785         put_mnt_ns(ns_private);
2786 out_mntput:
2787         mntput(root_mnt);
2788 out_err:
2789         kfree(nd);
2790         return ret;
2791 }
2792
2793 static int nfs4_try_mount(int flags, const char *dev_name,
2794                          struct nfs_parsed_mount_data *data,
2795                          struct vfsmount *mnt)
2796 {
2797         char *export_path;
2798         struct vfsmount *root_mnt;
2799         int error;
2800
2801         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2802
2803         export_path = data->nfs_server.export_path;
2804         data->nfs_server.export_path = "/";
2805         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2806                         data->nfs_server.hostname);
2807         data->nfs_server.export_path = export_path;
2808
2809         error = PTR_ERR(root_mnt);
2810         if (IS_ERR(root_mnt))
2811                 goto out;
2812
2813         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
2814
2815 out:
2816         dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n", error,
2817                         error != 0 ? " [error]" : "");
2818         return error;
2819 }
2820
2821 /*
2822  * Get the superblock for an NFS4 mountpoint
2823  */
2824 static int nfs4_get_sb(struct file_system_type *fs_type,
2825         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2826 {
2827         struct nfs_parsed_mount_data *data;
2828         int error = -ENOMEM;
2829
2830         data = nfs_alloc_parsed_mount_data(4);
2831         if (data == NULL)
2832                 goto out_free_data;
2833
2834         /* Validate the mount data */
2835         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2836         if (error < 0)
2837                 goto out;
2838
2839         error = nfs4_try_mount(flags, dev_name, data, mnt);
2840
2841 out:
2842         kfree(data->client_address);
2843         kfree(data->nfs_server.export_path);
2844         kfree(data->nfs_server.hostname);
2845         kfree(data->fscache_uniq);
2846 out_free_data:
2847         kfree(data);
2848         dprintk("<-- nfs4_get_sb() = %d%s\n", error,
2849                         error != 0 ? " [error]" : "");
2850         return error;
2851 }
2852
2853 static void nfs4_kill_super(struct super_block *sb)
2854 {
2855         struct nfs_server *server = NFS_SB(sb);
2856
2857         dprintk("--> %s\n", __func__);
2858         nfs_super_return_all_delegations(sb);
2859         kill_anon_super(sb);
2860         nfs_fscache_release_super_cookie(sb);
2861         nfs_free_server(server);
2862         dprintk("<-- %s\n", __func__);
2863 }
2864
2865 /*
2866  * Clone an NFS4 server record on xdev traversal (FSID-change)
2867  */
2868 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2869                             const char *dev_name, void *raw_data,
2870                             struct vfsmount *mnt)
2871 {
2872         struct nfs_clone_mount *data = raw_data;
2873         struct super_block *s;
2874         struct nfs_server *server;
2875         struct dentry *mntroot;
2876         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2877         struct nfs_sb_mountdata sb_mntdata = {
2878                 .mntflags = flags,
2879         };
2880         int error;
2881
2882         dprintk("--> nfs4_xdev_get_sb()\n");
2883
2884         /* create a new volume representation */
2885         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2886         if (IS_ERR(server)) {
2887                 error = PTR_ERR(server);
2888                 goto out_err_noserver;
2889         }
2890         sb_mntdata.server = server;
2891
2892         if (server->flags & NFS4_MOUNT_UNSHARED)
2893                 compare_super = NULL;
2894
2895         /* Get a superblock - note that we may end up sharing one that already exists */
2896         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2897         if (IS_ERR(s)) {
2898                 error = PTR_ERR(s);
2899                 goto out_err_nosb;
2900         }
2901
2902         if (s->s_fs_info != server) {
2903                 nfs_free_server(server);
2904                 server = NULL;
2905         } else {
2906                 error = nfs_bdi_register(server);
2907                 if (error)
2908                         goto error_splat_bdi;
2909         }
2910
2911         if (!s->s_root) {
2912                 /* initial superblock/root creation */
2913                 nfs4_clone_super(s, data->sb);
2914                 nfs_fscache_get_super_cookie(s, NULL, data);
2915         }
2916
2917         mntroot = nfs4_get_root(s, data->fh);
2918         if (IS_ERR(mntroot)) {
2919                 error = PTR_ERR(mntroot);
2920                 goto error_splat_super;
2921         }
2922         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2923                 dput(mntroot);
2924                 error = -ESTALE;
2925                 goto error_splat_super;
2926         }
2927
2928         s->s_flags |= MS_ACTIVE;
2929         mnt->mnt_sb = s;
2930         mnt->mnt_root = mntroot;
2931
2932         security_sb_clone_mnt_opts(data->sb, s);
2933
2934         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2935         return 0;
2936
2937 out_err_nosb:
2938         nfs_free_server(server);
2939 out_err_noserver:
2940         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2941         return error;
2942
2943 error_splat_super:
2944         if (server && !s->s_root)
2945                 bdi_unregister(&server->backing_dev_info);
2946 error_splat_bdi:
2947         deactivate_locked_super(s);
2948         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2949         return error;
2950 }
2951
2952 static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
2953                 int flags, const char *dev_name, void *raw_data,
2954                 struct vfsmount *mnt)
2955 {
2956         struct nfs_clone_mount *data = raw_data;
2957         struct super_block *s;
2958         struct nfs_server *server;
2959         struct dentry *mntroot;
2960         struct nfs_fh *mntfh;
2961         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2962         struct nfs_sb_mountdata sb_mntdata = {
2963                 .mntflags = flags,
2964         };
2965         int error = -ENOMEM;
2966
2967         dprintk("--> nfs4_referral_get_sb()\n");
2968
2969         mntfh = nfs_alloc_fhandle();
2970         if (mntfh == NULL)
2971                 goto out_err_nofh;
2972
2973         /* create a new volume representation */
2974         server = nfs4_create_referral_server(data, mntfh);
2975         if (IS_ERR(server)) {
2976                 error = PTR_ERR(server);
2977                 goto out_err_noserver;
2978         }
2979         sb_mntdata.server = server;
2980
2981         if (server->flags & NFS4_MOUNT_UNSHARED)
2982                 compare_super = NULL;
2983
2984         /* Get a superblock - note that we may end up sharing one that already exists */
2985         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2986         if (IS_ERR(s)) {
2987                 error = PTR_ERR(s);
2988                 goto out_err_nosb;
2989         }
2990
2991         if (s->s_fs_info != server) {
2992                 nfs_free_server(server);
2993                 server = NULL;
2994         } else {
2995                 error = nfs_bdi_register(server);
2996                 if (error)
2997                         goto error_splat_bdi;
2998         }
2999
3000         if (!s->s_root) {
3001                 /* initial superblock/root creation */
3002                 nfs4_fill_super(s);
3003                 nfs_fscache_get_super_cookie(s, NULL, data);
3004         }
3005
3006         mntroot = nfs4_get_root(s, mntfh);
3007         if (IS_ERR(mntroot)) {
3008                 error = PTR_ERR(mntroot);
3009                 goto error_splat_super;
3010         }
3011         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3012                 dput(mntroot);
3013                 error = -ESTALE;
3014                 goto error_splat_super;
3015         }
3016
3017         s->s_flags |= MS_ACTIVE;
3018         mnt->mnt_sb = s;
3019         mnt->mnt_root = mntroot;
3020
3021         security_sb_clone_mnt_opts(data->sb, s);
3022
3023         nfs_free_fhandle(mntfh);
3024         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3025         return 0;
3026
3027 out_err_nosb:
3028         nfs_free_server(server);
3029 out_err_noserver:
3030         nfs_free_fhandle(mntfh);
3031 out_err_nofh:
3032         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3033         return error;
3034
3035 error_splat_super:
3036         if (server && !s->s_root)
3037                 bdi_unregister(&server->backing_dev_info);
3038 error_splat_bdi:
3039         deactivate_locked_super(s);
3040         nfs_free_fhandle(mntfh);
3041         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3042         return error;
3043 }
3044
3045 /*
3046  * Create an NFS4 server record on referral traversal
3047  */
3048 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
3049                 int flags, const char *dev_name, void *raw_data,
3050                 struct vfsmount *mnt)
3051 {
3052         struct nfs_clone_mount *data = raw_data;
3053         char *export_path;
3054         struct vfsmount *root_mnt;
3055         int error;
3056
3057         dprintk("--> nfs4_referral_get_sb()\n");
3058
3059         export_path = data->mnt_path;
3060         data->mnt_path = "/";
3061
3062         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3063                         flags, data, data->hostname);
3064         data->mnt_path = export_path;
3065
3066         error = PTR_ERR(root_mnt);
3067         if (IS_ERR(root_mnt))
3068                 goto out;
3069
3070         error = nfs_follow_remote_path(root_mnt, export_path, mnt);
3071 out:
3072         dprintk("<-- nfs4_referral_get_sb() = %d%s\n", error,
3073                         error != 0 ? " [error]" : "");
3074         return error;
3075 }
3076
3077 #endif /* CONFIG_NFS_V4 */