fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/seq_file.h>
  43 #include <linux/mount.h>
  44 #include <linux/mnt_namespace.h>
  45 #include <linux/namei.h>
  46 #include <linux/nfs_idmap.h>
  47 #include <linux/vfs.h>
  48 #include <linux/inet.h>
  49 #include <linux/in6.h>
  50 #include <linux/slab.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56
  57 #include <asm/system.h>
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "pnfs.h"
  67
  68 #define NFSDBG_FACILITY         NFSDBG_VFS
  69
  70 #ifdef CONFIG_NFS_V3
  71 #define NFS_DEFAULT_VERSION 3
  72 #else
  73 #define NFS_DEFAULT_VERSION 2
  74 #endif
  75
  76 enum {
  77         /* Mount options that take no arguments */
  78         Opt_soft, Opt_hard,
  79         Opt_posix, Opt_noposix,
  80         Opt_cto, Opt_nocto,
  81         Opt_ac, Opt_noac,
  82         Opt_lock, Opt_nolock,
  83         Opt_v2, Opt_v3, Opt_v4,
  84         Opt_udp, Opt_tcp, Opt_rdma,
  85         Opt_acl, Opt_noacl,
  86         Opt_rdirplus, Opt_nordirplus,
  87         Opt_sharecache, Opt_nosharecache,
  88         Opt_resvport, Opt_noresvport,
  89         Opt_fscache, Opt_nofscache,
  90
  91         /* Mount options that take integer arguments */
  92         Opt_port,
  93         Opt_rsize, Opt_wsize, Opt_bsize,
  94         Opt_timeo, Opt_retrans,
  95         Opt_acregmin, Opt_acregmax,
  96         Opt_acdirmin, Opt_acdirmax,
  97         Opt_actimeo,
  98         Opt_namelen,
  99         Opt_mountport,
 100         Opt_mountvers,
 101         Opt_nfsvers,
 102         Opt_minorversion,
 103
 104         /* Mount options that take string arguments */
 105         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 106         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 107         Opt_lookupcache,
 108         Opt_fscache_uniq,
 109         Opt_local_lock,
 110
 111         /* Special mount options */
 112         Opt_userspace, Opt_deprecated, Opt_sloppy,
 113
 114         Opt_err
 115 };
 116
 117 static const match_table_t nfs_mount_option_tokens = {
 118         { Opt_userspace, "bg" },
 119         { Opt_userspace, "fg" },
 120         { Opt_userspace, "retry=%s" },
 121
 122         { Opt_sloppy, "sloppy" },
 123
 124         { Opt_soft, "soft" },
 125         { Opt_hard, "hard" },
 126         { Opt_deprecated, "intr" },
 127         { Opt_deprecated, "nointr" },
 128         { Opt_posix, "posix" },
 129         { Opt_noposix, "noposix" },
 130         { Opt_cto, "cto" },
 131         { Opt_nocto, "nocto" },
 132         { Opt_ac, "ac" },
 133         { Opt_noac, "noac" },
 134         { Opt_lock, "lock" },
 135         { Opt_nolock, "nolock" },
 136         { Opt_v2, "v2" },
 137         { Opt_v3, "v3" },
 138         { Opt_v4, "v4" },
 139         { Opt_udp, "udp" },
 140         { Opt_tcp, "tcp" },
 141         { Opt_rdma, "rdma" },
 142         { Opt_acl, "acl" },
 143         { Opt_noacl, "noacl" },
 144         { Opt_rdirplus, "rdirplus" },
 145         { Opt_nordirplus, "nordirplus" },
 146         { Opt_sharecache, "sharecache" },
 147         { Opt_nosharecache, "nosharecache" },
 148         { Opt_resvport, "resvport" },
 149         { Opt_noresvport, "noresvport" },
 150         { Opt_fscache, "fsc" },
 151         { Opt_nofscache, "nofsc" },
 152
 153         { Opt_port, "port=%s" },
 154         { Opt_rsize, "rsize=%s" },
 155         { Opt_wsize, "wsize=%s" },
 156         { Opt_bsize, "bsize=%s" },
 157         { Opt_timeo, "timeo=%s" },
 158         { Opt_retrans, "retrans=%s" },
 159         { Opt_acregmin, "acregmin=%s" },
 160         { Opt_acregmax, "acregmax=%s" },
 161         { Opt_acdirmin, "acdirmin=%s" },
 162         { Opt_acdirmax, "acdirmax=%s" },
 163         { Opt_actimeo, "actimeo=%s" },
 164         { Opt_namelen, "namlen=%s" },
 165         { Opt_mountport, "mountport=%s" },
 166         { Opt_mountvers, "mountvers=%s" },
 167         { Opt_nfsvers, "nfsvers=%s" },
 168         { Opt_nfsvers, "vers=%s" },
 169         { Opt_minorversion, "minorversion=%s" },
 170
 171         { Opt_sec, "sec=%s" },
 172         { Opt_proto, "proto=%s" },
 173         { Opt_mountproto, "mountproto=%s" },
 174         { Opt_addr, "addr=%s" },
 175         { Opt_clientaddr, "clientaddr=%s" },
 176         { Opt_mounthost, "mounthost=%s" },
 177         { Opt_mountaddr, "mountaddr=%s" },
 178
 179         { Opt_lookupcache, "lookupcache=%s" },
 180         { Opt_fscache_uniq, "fsc=%s" },
 181         { Opt_local_lock, "local_lock=%s" },
 182
 183         { Opt_err, NULL }
 184 };
 185
 186 enum {
 187         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 188
 189         Opt_xprt_err
 190 };
 191
 192 static const match_table_t nfs_xprt_protocol_tokens = {
 193         { Opt_xprt_udp, "udp" },
 194         { Opt_xprt_udp6, "udp6" },
 195         { Opt_xprt_tcp, "tcp" },
 196         { Opt_xprt_tcp6, "tcp6" },
 197         { Opt_xprt_rdma, "rdma" },
 198
 199         { Opt_xprt_err, NULL }
 200 };
 201
 202 enum {
 203         Opt_sec_none, Opt_sec_sys,
 204         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 205         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 206         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 207
 208         Opt_sec_err
 209 };
 210
 211 static const match_table_t nfs_secflavor_tokens = {
 212         { Opt_sec_none, "none" },
 213         { Opt_sec_none, "null" },
 214         { Opt_sec_sys, "sys" },
 215
 216         { Opt_sec_krb5, "krb5" },
 217         { Opt_sec_krb5i, "krb5i" },
 218         { Opt_sec_krb5p, "krb5p" },
 219
 220         { Opt_sec_lkey, "lkey" },
 221         { Opt_sec_lkeyi, "lkeyi" },
 222         { Opt_sec_lkeyp, "lkeyp" },
 223
 224         { Opt_sec_spkm, "spkm3" },
 225         { Opt_sec_spkmi, "spkm3i" },
 226         { Opt_sec_spkmp, "spkm3p" },
 227
 228         { Opt_sec_err, NULL }
 229 };
 230
 231 enum {
 232         Opt_lookupcache_all, Opt_lookupcache_positive,
 233         Opt_lookupcache_none,
 234
 235         Opt_lookupcache_err
 236 };
 237
 238 static match_table_t nfs_lookupcache_tokens = {
 239         { Opt_lookupcache_all, "all" },
 240         { Opt_lookupcache_positive, "pos" },
 241         { Opt_lookupcache_positive, "positive" },
 242         { Opt_lookupcache_none, "none" },
 243
 244         { Opt_lookupcache_err, NULL }
 245 };
 246
 247 enum {
 248         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 249         Opt_local_lock_none,
 250
 251         Opt_local_lock_err
 252 };
 253
 254 static match_table_t nfs_local_lock_tokens = {
 255         { Opt_local_lock_all, "all" },
 256         { Opt_local_lock_flock, "flock" },
 257         { Opt_local_lock_posix, "posix" },
 258         { Opt_local_lock_none, "none" },
 259
 260         { Opt_local_lock_err, NULL }
 261 };
 262
 263
 264 static void nfs_umount_begin(struct super_block *);
 265 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 266 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 267 static int  nfs_show_devname(struct seq_file *, struct vfsmount *);
 268 static int  nfs_show_path(struct seq_file *, struct vfsmount *);
 269 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 270 static struct dentry *nfs_fs_mount(struct file_system_type *,
 271                 int, const char *, void *);
 272 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 273                 int flags, const char *dev_name, void *raw_data);
 274 static void nfs_put_super(struct super_block *);
 275 static void nfs_kill_super(struct super_block *);
 276 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 277
 278 static struct file_system_type nfs_fs_type = {
 279         .owner          = THIS_MODULE,
 280         .name           = "nfs",
 281         .mount          = nfs_fs_mount,
 282         .kill_sb        = nfs_kill_super,
 283         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 284 };
 285
 286 struct file_system_type nfs_xdev_fs_type = {
 287         .owner          = THIS_MODULE,
 288         .name           = "nfs",
 289         .mount          = nfs_xdev_mount,
 290         .kill_sb        = nfs_kill_super,
 291         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 292 };
 293
 294 static const struct super_operations nfs_sops = {
 295         .alloc_inode    = nfs_alloc_inode,
 296         .destroy_inode  = nfs_destroy_inode,
 297         .write_inode    = nfs_write_inode,
 298         .put_super      = nfs_put_super,
 299         .statfs         = nfs_statfs,
 300         .evict_inode    = nfs_evict_inode,
 301         .umount_begin   = nfs_umount_begin,
 302         .show_options   = nfs_show_options,
 303         .show_devname   = nfs_show_devname,
 304         .show_path      = nfs_show_path,
 305         .show_stats     = nfs_show_stats,
 306         .remount_fs     = nfs_remount,
 307 };
 308
 309 #ifdef CONFIG_NFS_V4
 310 static int nfs4_validate_text_mount_data(void *options,
 311         struct nfs_parsed_mount_data *args, const char *dev_name);
 312 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
 313         struct nfs_parsed_mount_data *data);
 314 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
 315         int flags, const char *dev_name, void *raw_data);
 316 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
 317         int flags, const char *dev_name, void *raw_data);
 318 static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
 319         int flags, const char *dev_name, void *raw_data);
 320 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
 321         int flags, const char *dev_name, void *raw_data);
 322 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
 323         int flags, const char *dev_name, void *raw_data);
 324 static void nfs4_kill_super(struct super_block *sb);
 325
 326 static struct file_system_type nfs4_fs_type = {
 327         .owner          = THIS_MODULE,
 328         .name           = "nfs4",
 329         .mount          = nfs4_mount,
 330         .kill_sb        = nfs4_kill_super,
 331         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 332 };
 333
 334 static struct file_system_type nfs4_remote_fs_type = {
 335         .owner          = THIS_MODULE,
 336         .name           = "nfs4",
 337         .mount          = nfs4_remote_mount,
 338         .kill_sb        = nfs4_kill_super,
 339         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 340 };
 341
 342 struct file_system_type nfs4_xdev_fs_type = {
 343         .owner          = THIS_MODULE,
 344         .name           = "nfs4",
 345         .mount          = nfs4_xdev_mount,
 346         .kill_sb        = nfs4_kill_super,
 347         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 348 };
 349
 350 static struct file_system_type nfs4_remote_referral_fs_type = {
 351         .owner          = THIS_MODULE,
 352         .name           = "nfs4",
 353         .mount          = nfs4_remote_referral_mount,
 354         .kill_sb        = nfs4_kill_super,
 355         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 356 };
 357
 358 struct file_system_type nfs4_referral_fs_type = {
 359         .owner          = THIS_MODULE,
 360         .name           = "nfs4",
 361         .mount          = nfs4_referral_mount,
 362         .kill_sb        = nfs4_kill_super,
 363         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 364 };
 365
 366 static const struct super_operations nfs4_sops = {
 367         .alloc_inode    = nfs_alloc_inode,
 368         .destroy_inode  = nfs_destroy_inode,
 369         .write_inode    = nfs_write_inode,
 370         .put_super      = nfs_put_super,
 371         .statfs         = nfs_statfs,
 372         .evict_inode    = nfs4_evict_inode,
 373         .umount_begin   = nfs_umount_begin,
 374         .show_options   = nfs_show_options,
 375         .show_devname   = nfs_show_devname,
 376         .show_path      = nfs_show_path,
 377         .show_stats     = nfs_show_stats,
 378         .remount_fs     = nfs_remount,
 379 };
 380 #endif
 381
 382 static struct shrinker acl_shrinker = {
 383         .shrink         = nfs_access_cache_shrinker,
 384         .seeks          = DEFAULT_SEEKS,
 385 };
 386
 387 /*
 388  * Register the NFS filesystems
 389  */
 390 int __init register_nfs_fs(void)
 391 {
 392         int ret;
 393
 394         ret = register_filesystem(&nfs_fs_type);
 395         if (ret < 0)
 396                 goto error_0;
 397
 398         ret = nfs_register_sysctl();
 399         if (ret < 0)
 400                 goto error_1;
 401 #ifdef CONFIG_NFS_V4
 402         ret = register_filesystem(&nfs4_fs_type);
 403         if (ret < 0)
 404                 goto error_2;
 405 #endif
 406         register_shrinker(&acl_shrinker);
 407         return 0;
 408
 409 #ifdef CONFIG_NFS_V4
 410 error_2:
 411         nfs_unregister_sysctl();
 412 #endif
 413 error_1:
 414         unregister_filesystem(&nfs_fs_type);
 415 error_0:
 416         return ret;
 417 }
 418
 419 /*
 420  * Unregister the NFS filesystems
 421  */
 422 void __exit unregister_nfs_fs(void)
 423 {
 424         unregister_shrinker(&acl_shrinker);
 425 #ifdef CONFIG_NFS_V4
 426         unregister_filesystem(&nfs4_fs_type);
 427 #endif
 428         nfs_unregister_sysctl();
 429         unregister_filesystem(&nfs_fs_type);
 430 }
 431
 432 void nfs_sb_active(struct super_block *sb)
 433 {
 434         struct nfs_server *server = NFS_SB(sb);
 435
 436         if (atomic_inc_return(&server->active) == 1)
 437                 atomic_inc(&sb->s_active);
 438 }
 439
 440 void nfs_sb_deactive(struct super_block *sb)
 441 {
 442         struct nfs_server *server = NFS_SB(sb);
 443
 444         if (atomic_dec_and_test(&server->active))
 445                 deactivate_super(sb);
 446 }
 447
 448 /*
 449  * Deliver file system statistics to userspace
 450  */
 451 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 452 {
 453         struct nfs_server *server = NFS_SB(dentry->d_sb);
 454         unsigned char blockbits;
 455         unsigned long blockres;
 456         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 457         struct nfs_fsstat res;
 458         int error = -ENOMEM;
 459
 460         res.fattr = nfs_alloc_fattr();
 461         if (res.fattr == NULL)
 462                 goto out_err;
 463
 464         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 465         if (unlikely(error == -ESTALE)) {
 466                 struct dentry *pd_dentry;
 467
 468                 pd_dentry = dget_parent(dentry);
 469                 if (pd_dentry != NULL) {
 470                         nfs_zap_caches(pd_dentry->d_inode);
 471                         dput(pd_dentry);
 472                 }
 473         }
 474         nfs_free_fattr(res.fattr);
 475         if (error < 0)
 476                 goto out_err;
 477
 478         buf->f_type = NFS_SUPER_MAGIC;
 479
 480         /*
 481          * Current versions of glibc do not correctly handle the
 482          * case where f_frsize != f_bsize.  Eventually we want to
 483          * report the value of wtmult in this field.
 484          */
 485         buf->f_frsize = dentry->d_sb->s_blocksize;
 486
 487         /*
 488          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 489          * are reported in units of f_frsize.  Linux hasn't had
 490          * an f_frsize field in its statfs struct until recently,
 491          * thus historically Linux's sys_statfs reports these
 492          * fields in units of f_bsize.
 493          */
 494         buf->f_bsize = dentry->d_sb->s_blocksize;
 495         blockbits = dentry->d_sb->s_blocksize_bits;
 496         blockres = (1 << blockbits) - 1;
 497         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 498         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 499         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 500
 501         buf->f_files = res.tfiles;
 502         buf->f_ffree = res.afiles;
 503
 504         buf->f_namelen = server->namelen;
 505
 506         return 0;
 507
 508  out_err:
 509         dprintk("%s: statfs error = %d\n", __func__, -error);
 510         return error;
 511 }
 512
 513 /*
 514  * Map the security flavour number to a name
 515  */
 516 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 517 {
 518         static const struct {
 519                 rpc_authflavor_t flavour;
 520                 const char *str;
 521         } sec_flavours[] = {
 522                 { RPC_AUTH_NULL, "null" },
 523                 { RPC_AUTH_UNIX, "sys" },
 524                 { RPC_AUTH_GSS_KRB5, "krb5" },
 525                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 526                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 527                 { RPC_AUTH_GSS_LKEY, "lkey" },
 528                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 529                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 530                 { RPC_AUTH_GSS_SPKM, "spkm" },
 531                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 532                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 533                 { UINT_MAX, "unknown" }
 534         };
 535         int i;
 536
 537         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 538                 if (sec_flavours[i].flavour == flavour)
 539                         break;
 540         }
 541         return sec_flavours[i].str;
 542 }
 543
 544 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 545                                   int showdefaults)
 546 {
 547         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 548
 549         seq_printf(m, ",mountproto=");
 550         switch (sap->sa_family) {
 551         case AF_INET:
 552                 switch (nfss->mountd_protocol) {
 553                 case IPPROTO_UDP:
 554                         seq_printf(m, RPCBIND_NETID_UDP);
 555                         break;
 556                 case IPPROTO_TCP:
 557                         seq_printf(m, RPCBIND_NETID_TCP);
 558                         break;
 559                 default:
 560                         if (showdefaults)
 561                                 seq_printf(m, "auto");
 562                 }
 563                 break;
 564         case AF_INET6:
 565                 switch (nfss->mountd_protocol) {
 566                 case IPPROTO_UDP:
 567                         seq_printf(m, RPCBIND_NETID_UDP6);
 568                         break;
 569                 case IPPROTO_TCP:
 570                         seq_printf(m, RPCBIND_NETID_TCP6);
 571                         break;
 572                 default:
 573                         if (showdefaults)
 574                                 seq_printf(m, "auto");
 575                 }
 576                 break;
 577         default:
 578                 if (showdefaults)
 579                         seq_printf(m, "auto");
 580         }
 581 }
 582
 583 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 584                                     int showdefaults)
 585 {
 586         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 587
 588         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 589                 return;
 590
 591         switch (sap->sa_family) {
 592         case AF_INET: {
 593                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 594                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 595                 break;
 596         }
 597         case AF_INET6: {
 598                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 599                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 600                 break;
 601         }
 602         default:
 603                 if (showdefaults)
 604                         seq_printf(m, ",mountaddr=unspecified");
 605         }
 606
 607         if (nfss->mountd_version || showdefaults)
 608                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 609         if ((nfss->mountd_port &&
 610                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 611                 showdefaults)
 612                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 613
 614         nfs_show_mountd_netid(m, nfss, showdefaults);
 615 }
 616
 617 #ifdef CONFIG_NFS_V4
 618 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 619                                     int showdefaults)
 620 {
 621         struct nfs_client *clp = nfss->nfs_client;
 622
 623         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 624         seq_printf(m, ",minorversion=%u", clp->cl_minorversion);
 625 }
 626 #else
 627 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 628                                     int showdefaults)
 629 {
 630 }
 631 #endif
 632
 633 /*
 634  * Describe the mount options in force on this server representation
 635  */
 636 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 637                                    int showdefaults)
 638 {
 639         static const struct proc_nfs_info {
 640                 int flag;
 641                 const char *str;
 642                 const char *nostr;
 643         } nfs_info[] = {
 644                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 645                 { NFS_MOUNT_POSIX, ",posix", "" },
 646                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 647                 { NFS_MOUNT_NOAC, ",noac", "" },
 648                 { NFS_MOUNT_NONLM, ",nolock", "" },
 649                 { NFS_MOUNT_NOACL, ",noacl", "" },
 650                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 651                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 652                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 653                 { 0, NULL, NULL }
 654         };
 655         const struct proc_nfs_info *nfs_infop;
 656         struct nfs_client *clp = nfss->nfs_client;
 657         u32 version = clp->rpc_ops->version;
 658         int local_flock, local_fcntl;
 659
 660         seq_printf(m, ",vers=%u", version);
 661         seq_printf(m, ",rsize=%u", nfss->rsize);
 662         seq_printf(m, ",wsize=%u", nfss->wsize);
 663         if (nfss->bsize != 0)
 664                 seq_printf(m, ",bsize=%u", nfss->bsize);
 665         seq_printf(m, ",namlen=%u", nfss->namelen);
 666         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 667                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 668         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 669                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 670         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 671                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 672         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 673                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 674         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 675                 if (nfss->flags & nfs_infop->flag)
 676                         seq_puts(m, nfs_infop->str);
 677                 else
 678                         seq_puts(m, nfs_infop->nostr);
 679         }
 680         seq_printf(m, ",proto=%s",
 681                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 682         if (version == 4) {
 683                 if (nfss->port != NFS_PORT)
 684                         seq_printf(m, ",port=%u", nfss->port);
 685         } else
 686                 if (nfss->port)
 687                         seq_printf(m, ",port=%u", nfss->port);
 688
 689         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 690         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 691         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 692
 693         if (version != 4)
 694                 nfs_show_mountd_options(m, nfss, showdefaults);
 695         else
 696                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 697
 698         if (nfss->options & NFS_OPTION_FSCACHE)
 699                 seq_printf(m, ",fsc");
 700
 701         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 702                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 703                         seq_printf(m, ",lookupcache=none");
 704                 else
 705                         seq_printf(m, ",lookupcache=pos");
 706         }
 707
 708         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 709         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 710
 711         if (!local_flock && !local_fcntl)
 712                 seq_printf(m, ",local_lock=none");
 713         else if (local_flock && local_fcntl)
 714                 seq_printf(m, ",local_lock=all");
 715         else if (local_flock)
 716                 seq_printf(m, ",local_lock=flock");
 717         else
 718                 seq_printf(m, ",local_lock=posix");
 719 }
 720
 721 /*
 722  * Describe the mount options on this VFS mountpoint
 723  */
 724 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 725 {
 726         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 727
 728         nfs_show_mount_options(m, nfss, 0);
 729
 730         seq_printf(m, ",addr=%s",
 731                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 732                                                         RPC_DISPLAY_ADDR));
 733
 734         return 0;
 735 }
 736 #ifdef CONFIG_NFS_V4_1
 737 void show_sessions(struct seq_file *m, struct nfs_server *server)
 738 {
 739         if (nfs4_has_session(server->nfs_client))
 740                 seq_printf(m, ",sessions");
 741 }
 742 #else
 743 void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 744 #endif
 745
 746 #ifdef CONFIG_NFS_V4_1
 747 void show_pnfs(struct seq_file *m, struct nfs_server *server)
 748 {
 749         seq_printf(m, ",pnfs=");
 750         if (server->pnfs_curr_ld)
 751                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 752         else
 753                 seq_printf(m, "not configured");
 754 }
 755 #else  /* CONFIG_NFS_V4_1 */
 756 void show_pnfs(struct seq_file *m, struct nfs_server *server) {}
 757 #endif /* CONFIG_NFS_V4_1 */
 758
 759 static int nfs_show_devname(struct seq_file *m, struct vfsmount *mnt)
 760 {
 761         char *page = (char *) __get_free_page(GFP_KERNEL);
 762         char *devname, *dummy;
 763         int err = 0;
 764         if (!page)
 765                 return -ENOMEM;
 766         devname = nfs_path(&dummy, mnt->mnt_root, page, PAGE_SIZE);
 767         if (IS_ERR(devname))
 768                 err = PTR_ERR(devname);
 769         else
 770                 seq_escape(m, devname, " \t\n\\");
 771         free_page((unsigned long)page);
 772         return err;
 773 }
 774
 775 static int nfs_show_path(struct seq_file *m, struct vfsmount *mnt)
 776 {
 777         seq_puts(m, "/");
 778         return 0;
 779 }
 780
 781 /*
 782  * Present statistical information for this VFS mountpoint
 783  */
 784 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 785 {
 786         int i, cpu;
 787         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 788         struct rpc_auth *auth = nfss->client->cl_auth;
 789         struct nfs_iostats totals = { };
 790
 791         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 792
 793         /*
 794          * Display all mount option settings
 795          */
 796         seq_printf(m, "\n\topts:\t");
 797         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 798         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 799         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 800         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 801         nfs_show_mount_options(m, nfss, 1);
 802
 803         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 804
 805         seq_printf(m, "\n\tcaps:\t");
 806         seq_printf(m, "caps=0x%x", nfss->caps);
 807         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 808         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 809         seq_printf(m, ",bsize=%u", nfss->bsize);
 810         seq_printf(m, ",namlen=%u", nfss->namelen);
 811
 812 #ifdef CONFIG_NFS_V4
 813         if (nfss->nfs_client->rpc_ops->version == 4) {
 814                 seq_printf(m, "\n\tnfsv4:\t");
 815                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 816                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 817                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 818                 show_sessions(m, nfss);
 819                 show_pnfs(m, nfss);
 820         }
 821 #endif
 822
 823         /*
 824          * Display security flavor in effect for this mount
 825          */
 826         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 827         if (auth->au_flavor)
 828                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 829
 830         /*
 831          * Display superblock I/O counters
 832          */
 833         for_each_possible_cpu(cpu) {
 834                 struct nfs_iostats *stats;
 835
 836                 preempt_disable();
 837                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 838
 839                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 840                         totals.events[i] += stats->events[i];
 841                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 842                         totals.bytes[i] += stats->bytes[i];
 843 #ifdef CONFIG_NFS_FSCACHE
 844                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 845                         totals.fscache[i] += stats->fscache[i];
 846 #endif
 847
 848                 preempt_enable();
 849         }
 850
 851         seq_printf(m, "\n\tevents:\t");
 852         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 853                 seq_printf(m, "%lu ", totals.events[i]);
 854         seq_printf(m, "\n\tbytes:\t");
 855         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 856                 seq_printf(m, "%Lu ", totals.bytes[i]);
 857 #ifdef CONFIG_NFS_FSCACHE
 858         if (nfss->options & NFS_OPTION_FSCACHE) {
 859                 seq_printf(m, "\n\tfsc:\t");
 860                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 861                         seq_printf(m, "%Lu ", totals.bytes[i]);
 862         }
 863 #endif
 864         seq_printf(m, "\n");
 865
 866         rpc_print_iostats(m, nfss->client);
 867
 868         return 0;
 869 }
 870
 871 /*
 872  * Begin unmount by attempting to remove all automounted mountpoints we added
 873  * in response to xdev traversals and referrals
 874  */
 875 static void nfs_umount_begin(struct super_block *sb)
 876 {
 877         struct nfs_server *server;
 878         struct rpc_clnt *rpc;
 879
 880         server = NFS_SB(sb);
 881         /* -EIO all pending I/O */
 882         rpc = server->client_acl;
 883         if (!IS_ERR(rpc))
 884                 rpc_killall_tasks(rpc);
 885         rpc = server->client;
 886         if (!IS_ERR(rpc))
 887                 rpc_killall_tasks(rpc);
 888 }
 889
 890 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
 891 {
 892         struct nfs_parsed_mount_data *data;
 893
 894         data = kzalloc(sizeof(*data), GFP_KERNEL);
 895         if (data) {
 896                 data->acregmin          = NFS_DEF_ACREGMIN;
 897                 data->acregmax          = NFS_DEF_ACREGMAX;
 898                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 899                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 900                 data->mount_server.port = NFS_UNSPEC_PORT;
 901                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 902                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 903                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 904                 data->auth_flavor_len   = 1;
 905                 data->version           = version;
 906                 data->minorversion      = 0;
 907         }
 908         return data;
 909 }
 910
 911 /*
 912  * Sanity-check a server address provided by the mount command.
 913  *
 914  * Address family must be initialized, and address must not be
 915  * the ANY address for that family.
 916  */
 917 static int nfs_verify_server_address(struct sockaddr *addr)
 918 {
 919         switch (addr->sa_family) {
 920         case AF_INET: {
 921                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 922                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 923         }
 924         case AF_INET6: {
 925                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 926                 return !ipv6_addr_any(sa);
 927         }
 928         }
 929
 930         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 931         return 0;
 932 }
 933
 934 /*
 935  * Select between a default port value and a user-specified port value.
 936  * If a zero value is set, then autobind will be used.
 937  */
 938 static void nfs_set_port(struct sockaddr *sap, int *port,
 939                                  const unsigned short default_port)
 940 {
 941         if (*port == NFS_UNSPEC_PORT)
 942                 *port = default_port;
 943
 944         rpc_set_port(sap, *port);
 945 }
 946
 947 /*
 948  * Sanity check the NFS transport protocol.
 949  *
 950  */
 951 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 952 {
 953         switch (mnt->nfs_server.protocol) {
 954         case XPRT_TRANSPORT_UDP:
 955         case XPRT_TRANSPORT_TCP:
 956         case XPRT_TRANSPORT_RDMA:
 957                 break;
 958         default:
 959                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 960         }
 961 }
 962
 963 /*
 964  * For text based NFSv2/v3 mounts, the mount protocol transport default
 965  * settings should depend upon the specified NFS transport.
 966  */
 967 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 968 {
 969         nfs_validate_transport_protocol(mnt);
 970
 971         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 972             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 973                         return;
 974         switch (mnt->nfs_server.protocol) {
 975         case XPRT_TRANSPORT_UDP:
 976                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 977                 break;
 978         case XPRT_TRANSPORT_TCP:
 979         case XPRT_TRANSPORT_RDMA:
 980                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 981         }
 982 }
 983
 984 /*
 985  * Parse the value of the 'sec=' option.
 986  */
 987 static int nfs_parse_security_flavors(char *value,
 988                                       struct nfs_parsed_mount_data *mnt)
 989 {
 990         substring_t args[MAX_OPT_ARGS];
 991
 992         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 993
 994         switch (match_token(value, nfs_secflavor_tokens, args)) {
 995         case Opt_sec_none:
 996                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 997                 break;
 998         case Opt_sec_sys:
 999                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1000                 break;
1001         case Opt_sec_krb5:
1002                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1003                 break;
1004         case Opt_sec_krb5i:
1005                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1006                 break;
1007         case Opt_sec_krb5p:
1008                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1009                 break;
1010         case Opt_sec_lkey:
1011                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1012                 break;
1013         case Opt_sec_lkeyi:
1014                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1015                 break;
1016         case Opt_sec_lkeyp:
1017                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1018                 break;
1019         case Opt_sec_spkm:
1020                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1021                 break;
1022         case Opt_sec_spkmi:
1023                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1024                 break;
1025         case Opt_sec_spkmp:
1026                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1027                 break;
1028         default:
1029                 return 0;
1030         }
1031
1032         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1033         mnt->auth_flavor_len = 1;
1034         return 1;
1035 }
1036
1037 static int nfs_get_option_str(substring_t args[], char **option)
1038 {
1039         kfree(*option);
1040         *option = match_strdup(args);
1041         return !option;
1042 }
1043
1044 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1045 {
1046         int rc;
1047         char *string;
1048
1049         string = match_strdup(args);
1050         if (string == NULL)
1051                 return -ENOMEM;
1052         rc = strict_strtoul(string, 10, option);
1053         kfree(string);
1054
1055         return rc;
1056 }
1057
1058 /*
1059  * Error-check and convert a string of mount options from user space into
1060  * a data structure.  The whole mount string is processed; bad options are
1061  * skipped as they are encountered.  If there were no errors, return 1;
1062  * otherwise return 0 (zero).
1063  */
1064 static int nfs_parse_mount_options(char *raw,
1065                                    struct nfs_parsed_mount_data *mnt)
1066 {
1067         char *p, *string, *secdata;
1068         int rc, sloppy = 0, invalid_option = 0;
1069         unsigned short protofamily = AF_UNSPEC;
1070         unsigned short mountfamily = AF_UNSPEC;
1071
1072         if (!raw) {
1073                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1074                 return 1;
1075         }
1076         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1077
1078         secdata = alloc_secdata();
1079         if (!secdata)
1080                 goto out_nomem;
1081
1082         rc = security_sb_copy_data(raw, secdata);
1083         if (rc)
1084                 goto out_security_failure;
1085
1086         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1087         if (rc)
1088                 goto out_security_failure;
1089
1090         free_secdata(secdata);
1091
1092         while ((p = strsep(&raw, ",")) != NULL) {
1093                 substring_t args[MAX_OPT_ARGS];
1094                 unsigned long option;
1095                 int token;
1096
1097                 if (!*p)
1098                         continue;
1099
1100                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1101
1102                 token = match_token(p, nfs_mount_option_tokens, args);
1103                 switch (token) {
1104
1105                 /*
1106                  * boolean options:  foo/nofoo
1107                  */
1108                 case Opt_soft:
1109                         mnt->flags |= NFS_MOUNT_SOFT;
1110                         break;
1111                 case Opt_hard:
1112                         mnt->flags &= ~NFS_MOUNT_SOFT;
1113                         break;
1114                 case Opt_posix:
1115                         mnt->flags |= NFS_MOUNT_POSIX;
1116                         break;
1117                 case Opt_noposix:
1118                         mnt->flags &= ~NFS_MOUNT_POSIX;
1119                         break;
1120                 case Opt_cto:
1121                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1122                         break;
1123                 case Opt_nocto:
1124                         mnt->flags |= NFS_MOUNT_NOCTO;
1125                         break;
1126                 case Opt_ac:
1127                         mnt->flags &= ~NFS_MOUNT_NOAC;
1128                         break;
1129                 case Opt_noac:
1130                         mnt->flags |= NFS_MOUNT_NOAC;
1131                         break;
1132                 case Opt_lock:
1133                         mnt->flags &= ~NFS_MOUNT_NONLM;
1134                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1135                                         NFS_MOUNT_LOCAL_FCNTL);
1136                         break;
1137                 case Opt_nolock:
1138                         mnt->flags |= NFS_MOUNT_NONLM;
1139                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1140                                        NFS_MOUNT_LOCAL_FCNTL);
1141                         break;
1142                 case Opt_v2:
1143                         mnt->flags &= ~NFS_MOUNT_VER3;
1144                         mnt->version = 2;
1145                         break;
1146                 case Opt_v3:
1147                         mnt->flags |= NFS_MOUNT_VER3;
1148                         mnt->version = 3;
1149                         break;
1150                 case Opt_v4:
1151                         mnt->flags &= ~NFS_MOUNT_VER3;
1152                         mnt->version = 4;
1153                         break;
1154                 case Opt_udp:
1155                         mnt->flags &= ~NFS_MOUNT_TCP;
1156                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1157                         break;
1158                 case Opt_tcp:
1159                         mnt->flags |= NFS_MOUNT_TCP;
1160                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1161                         break;
1162                 case Opt_rdma:
1163                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1164                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1165                         xprt_load_transport(p);
1166                         break;
1167                 case Opt_acl:
1168                         mnt->flags &= ~NFS_MOUNT_NOACL;
1169                         break;
1170                 case Opt_noacl:
1171                         mnt->flags |= NFS_MOUNT_NOACL;
1172                         break;
1173                 case Opt_rdirplus:
1174                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1175                         break;
1176                 case Opt_nordirplus:
1177                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1178                         break;
1179                 case Opt_sharecache:
1180                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1181                         break;
1182                 case Opt_nosharecache:
1183                         mnt->flags |= NFS_MOUNT_UNSHARED;
1184                         break;
1185                 case Opt_resvport:
1186                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1187                         break;
1188                 case Opt_noresvport:
1189                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1190                         break;
1191                 case Opt_fscache:
1192                         mnt->options |= NFS_OPTION_FSCACHE;
1193                         kfree(mnt->fscache_uniq);
1194                         mnt->fscache_uniq = NULL;
1195                         break;
1196                 case Opt_nofscache:
1197                         mnt->options &= ~NFS_OPTION_FSCACHE;
1198                         kfree(mnt->fscache_uniq);
1199                         mnt->fscache_uniq = NULL;
1200                         break;
1201
1202                 /*
1203                  * options that take numeric values
1204                  */
1205                 case Opt_port:
1206                         if (nfs_get_option_ul(args, &option) ||
1207                             option > USHRT_MAX)
1208                                 goto out_invalid_value;
1209                         mnt->nfs_server.port = option;
1210                         break;
1211                 case Opt_rsize:
1212                         if (nfs_get_option_ul(args, &option))
1213                                 goto out_invalid_value;
1214                         mnt->rsize = option;
1215                         break;
1216                 case Opt_wsize:
1217                         if (nfs_get_option_ul(args, &option))
1218                                 goto out_invalid_value;
1219                         mnt->wsize = option;
1220                         break;
1221                 case Opt_bsize:
1222                         if (nfs_get_option_ul(args, &option))
1223                                 goto out_invalid_value;
1224                         mnt->bsize = option;
1225                         break;
1226                 case Opt_timeo:
1227                         if (nfs_get_option_ul(args, &option) || option == 0)
1228                                 goto out_invalid_value;
1229                         mnt->timeo = option;
1230                         break;
1231                 case Opt_retrans:
1232                         if (nfs_get_option_ul(args, &option) || option == 0)
1233                                 goto out_invalid_value;
1234                         mnt->retrans = option;
1235                         break;
1236                 case Opt_acregmin:
1237                         if (nfs_get_option_ul(args, &option))
1238                                 goto out_invalid_value;
1239                         mnt->acregmin = option;
1240                         break;
1241                 case Opt_acregmax:
1242                         if (nfs_get_option_ul(args, &option))
1243                                 goto out_invalid_value;
1244                         mnt->acregmax = option;
1245                         break;
1246                 case Opt_acdirmin:
1247                         if (nfs_get_option_ul(args, &option))
1248                                 goto out_invalid_value;
1249                         mnt->acdirmin = option;
1250                         break;
1251                 case Opt_acdirmax:
1252                         if (nfs_get_option_ul(args, &option))
1253                                 goto out_invalid_value;
1254                         mnt->acdirmax = option;
1255                         break;
1256                 case Opt_actimeo:
1257                         if (nfs_get_option_ul(args, &option))
1258                                 goto out_invalid_value;
1259                         mnt->acregmin = mnt->acregmax =
1260                         mnt->acdirmin = mnt->acdirmax = option;
1261                         break;
1262                 case Opt_namelen:
1263                         if (nfs_get_option_ul(args, &option))
1264                                 goto out_invalid_value;
1265                         mnt->namlen = option;
1266                         break;
1267                 case Opt_mountport:
1268                         if (nfs_get_option_ul(args, &option) ||
1269                             option > USHRT_MAX)
1270                                 goto out_invalid_value;
1271                         mnt->mount_server.port = option;
1272                         break;
1273                 case Opt_mountvers:
1274                         if (nfs_get_option_ul(args, &option) ||
1275                             option < NFS_MNT_VERSION ||
1276                             option > NFS_MNT3_VERSION)
1277                                 goto out_invalid_value;
1278                         mnt->mount_server.version = option;
1279                         break;
1280                 case Opt_nfsvers:
1281                         if (nfs_get_option_ul(args, &option))
1282                                 goto out_invalid_value;
1283                         switch (option) {
1284                         case NFS2_VERSION:
1285                                 mnt->flags &= ~NFS_MOUNT_VER3;
1286                                 mnt->version = 2;
1287                                 break;
1288                         case NFS3_VERSION:
1289                                 mnt->flags |= NFS_MOUNT_VER3;
1290                                 mnt->version = 3;
1291                                 break;
1292                         case NFS4_VERSION:
1293                                 mnt->flags &= ~NFS_MOUNT_VER3;
1294                                 mnt->version = 4;
1295                                 break;
1296                         default:
1297                                 goto out_invalid_value;
1298                         }
1299                         break;
1300                 case Opt_minorversion:
1301                         if (nfs_get_option_ul(args, &option))
1302                                 goto out_invalid_value;
1303                         if (option > NFS4_MAX_MINOR_VERSION)
1304                                 goto out_invalid_value;
1305                         mnt->minorversion = option;
1306                         break;
1307
1308                 /*
1309                  * options that take text values
1310                  */
1311                 case Opt_sec:
1312                         string = match_strdup(args);
1313                         if (string == NULL)
1314                                 goto out_nomem;
1315                         rc = nfs_parse_security_flavors(string, mnt);
1316                         kfree(string);
1317                         if (!rc) {
1318                                 dfprintk(MOUNT, "NFS:   unrecognized "
1319                                                 "security flavor\n");
1320                                 return 0;
1321                         }
1322                         break;
1323                 case Opt_proto:
1324                         string = match_strdup(args);
1325                         if (string == NULL)
1326                                 goto out_nomem;
1327                         token = match_token(string,
1328                                             nfs_xprt_protocol_tokens, args);
1329
1330                         protofamily = AF_INET;
1331                         switch (token) {
1332                         case Opt_xprt_udp6:
1333                                 protofamily = AF_INET6;
1334                         case Opt_xprt_udp:
1335                                 mnt->flags &= ~NFS_MOUNT_TCP;
1336                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1337                                 break;
1338                         case Opt_xprt_tcp6:
1339                                 protofamily = AF_INET6;
1340                         case Opt_xprt_tcp:
1341                                 mnt->flags |= NFS_MOUNT_TCP;
1342                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1343                                 break;
1344                         case Opt_xprt_rdma:
1345                                 /* vector side protocols to TCP */
1346                                 mnt->flags |= NFS_MOUNT_TCP;
1347                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1348                                 xprt_load_transport(string);
1349                                 break;
1350                         default:
1351                                 dfprintk(MOUNT, "NFS:   unrecognized "
1352                                                 "transport protocol\n");
1353                                 kfree(string);
1354                                 return 0;
1355                         }
1356                         kfree(string);
1357                         break;
1358                 case Opt_mountproto:
1359                         string = match_strdup(args);
1360                         if (string == NULL)
1361                                 goto out_nomem;
1362                         token = match_token(string,
1363                                             nfs_xprt_protocol_tokens, args);
1364                         kfree(string);
1365
1366                         mountfamily = AF_INET;
1367                         switch (token) {
1368                         case Opt_xprt_udp6:
1369                                 mountfamily = AF_INET6;
1370                         case Opt_xprt_udp:
1371                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1372                                 break;
1373                         case Opt_xprt_tcp6:
1374                                 mountfamily = AF_INET6;
1375                         case Opt_xprt_tcp:
1376                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1377                                 break;
1378                         case Opt_xprt_rdma: /* not used for side protocols */
1379                         default:
1380                                 dfprintk(MOUNT, "NFS:   unrecognized "
1381                                                 "transport protocol\n");
1382                                 return 0;
1383                         }
1384                         break;
1385                 case Opt_addr:
1386                         string = match_strdup(args);
1387                         if (string == NULL)
1388                                 goto out_nomem;
1389                         mnt->nfs_server.addrlen =
1390                                 rpc_pton(string, strlen(string),
1391                                         (struct sockaddr *)
1392                                         &mnt->nfs_server.address,
1393                                         sizeof(mnt->nfs_server.address));
1394                         kfree(string);
1395                         if (mnt->nfs_server.addrlen == 0)
1396                                 goto out_invalid_address;
1397                         break;
1398                 case Opt_clientaddr:
1399                         if (nfs_get_option_str(args, &mnt->client_address))
1400                                 goto out_nomem;
1401                         break;
1402                 case Opt_mounthost:
1403                         if (nfs_get_option_str(args,
1404                                                &mnt->mount_server.hostname))
1405                                 goto out_nomem;
1406                         break;
1407                 case Opt_mountaddr:
1408                         string = match_strdup(args);
1409                         if (string == NULL)
1410                                 goto out_nomem;
1411                         mnt->mount_server.addrlen =
1412                                 rpc_pton(string, strlen(string),
1413                                         (struct sockaddr *)
1414                                         &mnt->mount_server.address,
1415                                         sizeof(mnt->mount_server.address));
1416                         kfree(string);
1417                         if (mnt->mount_server.addrlen == 0)
1418                                 goto out_invalid_address;
1419                         break;
1420                 case Opt_lookupcache:
1421                         string = match_strdup(args);
1422                         if (string == NULL)
1423                                 goto out_nomem;
1424                         token = match_token(string,
1425                                         nfs_lookupcache_tokens, args);
1426                         kfree(string);
1427                         switch (token) {
1428                                 case Opt_lookupcache_all:
1429                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1430                                         break;
1431                                 case Opt_lookupcache_positive:
1432                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1433                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1434                                         break;
1435                                 case Opt_lookupcache_none:
1436                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1437                                         break;
1438                                 default:
1439                                         dfprintk(MOUNT, "NFS:   invalid "
1440                                                         "lookupcache argument\n");
1441                                         return 0;
1442                         };
1443                         break;
1444                 case Opt_fscache_uniq:
1445                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1446                                 goto out_nomem;
1447                         mnt->options |= NFS_OPTION_FSCACHE;
1448                         break;
1449                 case Opt_local_lock:
1450                         string = match_strdup(args);
1451                         if (string == NULL)
1452                                 goto out_nomem;
1453                         token = match_token(string, nfs_local_lock_tokens,
1454                                         args);
1455                         kfree(string);
1456                         switch (token) {
1457                         case Opt_local_lock_all:
1458                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1459                                                NFS_MOUNT_LOCAL_FCNTL);
1460                                 break;
1461                         case Opt_local_lock_flock:
1462                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1463                                 break;
1464                         case Opt_local_lock_posix:
1465                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1466                                 break;
1467                         case Opt_local_lock_none:
1468                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1469                                                 NFS_MOUNT_LOCAL_FCNTL);
1470                                 break;
1471                         default:
1472                                 dfprintk(MOUNT, "NFS:   invalid "
1473                                                 "local_lock argument\n");
1474                                 return 0;
1475                         };
1476                         break;
1477
1478                 /*
1479                  * Special options
1480                  */
1481                 case Opt_sloppy:
1482                         sloppy = 1;
1483                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1484                         break;
1485                 case Opt_userspace:
1486                 case Opt_deprecated:
1487                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1488                                         "'%s'\n", p);
1489                         break;
1490
1491                 default:
1492                         invalid_option = 1;
1493                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1494                                         "'%s'\n", p);
1495                 }
1496         }
1497
1498         if (!sloppy && invalid_option)
1499                 return 0;
1500
1501         /*
1502          * verify that any proto=/mountproto= options match the address
1503          * familiies in the addr=/mountaddr= options.
1504          */
1505         if (protofamily != AF_UNSPEC &&
1506             protofamily != mnt->nfs_server.address.ss_family)
1507                 goto out_proto_mismatch;
1508
1509         if (mountfamily != AF_UNSPEC) {
1510                 if (mnt->mount_server.addrlen) {
1511                         if (mountfamily != mnt->mount_server.address.ss_family)
1512                                 goto out_mountproto_mismatch;
1513                 } else {
1514                         if (mountfamily != mnt->nfs_server.address.ss_family)
1515                                 goto out_mountproto_mismatch;
1516                 }
1517         }
1518
1519         return 1;
1520
1521 out_mountproto_mismatch:
1522         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1523                          "option\n");
1524         return 0;
1525 out_proto_mismatch:
1526         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1527         return 0;
1528 out_invalid_address:
1529         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1530         return 0;
1531 out_invalid_value:
1532         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1533         return 0;
1534 out_nomem:
1535         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1536         return 0;
1537 out_security_failure:
1538         free_secdata(secdata);
1539         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1540         return 0;
1541 }
1542
1543 /*
1544  * Match the requested auth flavors with the list returned by
1545  * the server.  Returns zero and sets the mount's authentication
1546  * flavor on success; returns -EACCES if server does not support
1547  * the requested flavor.
1548  */
1549 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1550                              struct nfs_mount_request *request)
1551 {
1552         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1553
1554         /*
1555          * Certain releases of Linux's mountd return an empty
1556          * flavor list.  To prevent behavioral regression with
1557          * these servers (ie. rejecting mounts that used to
1558          * succeed), revert to pre-2.6.32 behavior (no checking)
1559          * if the returned flavor list is empty.
1560          */
1561         if (server_authlist_len == 0)
1562                 return 0;
1563
1564         /*
1565          * We avoid sophisticated negotiating here, as there are
1566          * plenty of cases where we can get it wrong, providing
1567          * either too little or too much security.
1568          *
1569          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1570          * flavor listed first.  However, some servers list
1571          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1572          * preferred default, in args->auth_flavors[0] if user
1573          * didn't specify sec= mount option.
1574          */
1575         for (i = 0; i < args->auth_flavor_len; i++)
1576                 for (j = 0; j < server_authlist_len; j++)
1577                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1578                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1579                                         request->auth_flavs[j]);
1580                                 args->auth_flavors[0] = request->auth_flavs[j];
1581                                 return 0;
1582                         }
1583
1584         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1585         nfs_umount(request);
1586         return -EACCES;
1587 }
1588
1589 /*
1590  * Use the remote server's MOUNT service to request the NFS file handle
1591  * corresponding to the provided path.
1592  */
1593 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1594                          struct nfs_fh *root_fh)
1595 {
1596         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1597         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1598         struct nfs_mount_request request = {
1599                 .sap            = (struct sockaddr *)
1600                                                 &args->mount_server.address,
1601                 .dirpath        = args->nfs_server.export_path,
1602                 .protocol       = args->mount_server.protocol,
1603                 .fh             = root_fh,
1604                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1605                 .auth_flav_len  = &server_authlist_len,
1606                 .auth_flavs     = server_authlist,
1607         };
1608         int status;
1609
1610         if (args->mount_server.version == 0) {
1611                 switch (args->version) {
1612                         default:
1613                                 args->mount_server.version = NFS_MNT3_VERSION;
1614                                 break;
1615                         case 2:
1616                                 args->mount_server.version = NFS_MNT_VERSION;
1617                 }
1618         }
1619         request.version = args->mount_server.version;
1620
1621         if (args->mount_server.hostname)
1622                 request.hostname = args->mount_server.hostname;
1623         else
1624                 request.hostname = args->nfs_server.hostname;
1625
1626         /*
1627          * Construct the mount server's address.
1628          */
1629         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1630                 memcpy(request.sap, &args->nfs_server.address,
1631                        args->nfs_server.addrlen);
1632                 args->mount_server.addrlen = args->nfs_server.addrlen;
1633         }
1634         request.salen = args->mount_server.addrlen;
1635         nfs_set_port(request.sap, &args->mount_server.port, 0);
1636
1637         /*
1638          * Now ask the mount server to map our export path
1639          * to a file handle.
1640          */
1641         status = nfs_mount(&request);
1642         if (status != 0) {
1643                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1644                                 request.hostname, status);
1645                 return status;
1646         }
1647
1648         /*
1649          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1650          */
1651         if (args->mount_server.version != NFS_MNT3_VERSION)
1652                 return 0;
1653         return nfs_walk_authlist(args, &request);
1654 }
1655
1656 /*
1657  * Split "dev_name" into "hostname:export_path".
1658  *
1659  * The leftmost colon demarks the split between the server's hostname
1660  * and the export path.  If the hostname starts with a left square
1661  * bracket, then it may contain colons.
1662  *
1663  * Note: caller frees hostname and export path, even on error.
1664  */
1665 static int nfs_parse_devname(const char *dev_name,
1666                              char **hostname, size_t maxnamlen,
1667                              char **export_path, size_t maxpathlen)
1668 {
1669         size_t len;
1670         char *end;
1671
1672         /* Is the host name protected with square brakcets? */
1673         if (*dev_name == '[') {
1674                 end = strchr(++dev_name, ']');
1675                 if (end == NULL || end[1] != ':')
1676                         goto out_bad_devname;
1677
1678                 len = end - dev_name;
1679                 end++;
1680         } else {
1681                 char *comma;
1682
1683                 end = strchr(dev_name, ':');
1684                 if (end == NULL)
1685                         goto out_bad_devname;
1686                 len = end - dev_name;
1687
1688                 /* kill possible hostname list: not supported */
1689                 comma = strchr(dev_name, ',');
1690                 if (comma != NULL && comma < end)
1691                         *comma = 0;
1692         }
1693
1694         if (len > maxnamlen)
1695                 goto out_hostname;
1696
1697         /* N.B. caller will free nfs_server.hostname in all cases */
1698         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1699         if (*hostname == NULL)
1700                 goto out_nomem;
1701         len = strlen(++end);
1702         if (len > maxpathlen)
1703                 goto out_path;
1704         *export_path = kstrndup(end, len, GFP_KERNEL);
1705         if (!*export_path)
1706                 goto out_nomem;
1707
1708         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1709         return 0;
1710
1711 out_bad_devname:
1712         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1713         return -EINVAL;
1714
1715 out_nomem:
1716         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1717         return -ENOMEM;
1718
1719 out_hostname:
1720         dfprintk(MOUNT, "NFS: server hostname too long\n");
1721         return -ENAMETOOLONG;
1722
1723 out_path:
1724         dfprintk(MOUNT, "NFS: export pathname too long\n");
1725         return -ENAMETOOLONG;
1726 }
1727
1728 /*
1729  * Validate the NFS2/NFS3 mount data
1730  * - fills in the mount root filehandle
1731  *
1732  * For option strings, user space handles the following behaviors:
1733  *
1734  * + DNS: mapping server host name to IP address ("addr=" option)
1735  *
1736  * + failure mode: how to behave if a mount request can't be handled
1737  *   immediately ("fg/bg" option)
1738  *
1739  * + retry: how often to retry a mount request ("retry=" option)
1740  *
1741  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1742  *   mountproto=tcp after mountproto=udp, and so on
1743  */
1744 static int nfs_validate_mount_data(void *options,
1745                                    struct nfs_parsed_mount_data *args,
1746                                    struct nfs_fh *mntfh,
1747                                    const char *dev_name)
1748 {
1749         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1750         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1751
1752         if (data == NULL)
1753                 goto out_no_data;
1754
1755         switch (data->version) {
1756         case 1:
1757                 data->namlen = 0;
1758         case 2:
1759                 data->bsize = 0;
1760         case 3:
1761                 if (data->flags & NFS_MOUNT_VER3)
1762                         goto out_no_v3;
1763                 data->root.size = NFS2_FHSIZE;
1764                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1765         case 4:
1766                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1767                         goto out_no_sec;
1768         case 5:
1769                 memset(data->context, 0, sizeof(data->context));
1770         case 6:
1771                 if (data->flags & NFS_MOUNT_VER3) {
1772                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1773                                 goto out_invalid_fh;
1774                         mntfh->size = data->root.size;
1775                         args->version = 3;
1776                 } else {
1777                         mntfh->size = NFS2_FHSIZE;
1778                         args->version = 2;
1779                 }
1780
1781
1782                 memcpy(mntfh->data, data->root.data, mntfh->size);
1783                 if (mntfh->size < sizeof(mntfh->data))
1784                         memset(mntfh->data + mntfh->size, 0,
1785                                sizeof(mntfh->data) - mntfh->size);
1786
1787                 /*
1788                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1789                  * can deal with.
1790                  */
1791                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1792                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1793                 args->rsize             = data->rsize;
1794                 args->wsize             = data->wsize;
1795                 args->timeo             = data->timeo;
1796                 args->retrans           = data->retrans;
1797                 args->acregmin          = data->acregmin;
1798                 args->acregmax          = data->acregmax;
1799                 args->acdirmin          = data->acdirmin;
1800                 args->acdirmax          = data->acdirmax;
1801
1802                 memcpy(sap, &data->addr, sizeof(data->addr));
1803                 args->nfs_server.addrlen = sizeof(data->addr);
1804                 if (!nfs_verify_server_address(sap))
1805                         goto out_no_address;
1806
1807                 if (!(data->flags & NFS_MOUNT_TCP))
1808                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1809                 /* N.B. caller will free nfs_server.hostname in all cases */
1810                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1811                 args->namlen            = data->namlen;
1812                 args->bsize             = data->bsize;
1813
1814                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1815                         args->auth_flavors[0] = data->pseudoflavor;
1816                 if (!args->nfs_server.hostname)
1817                         goto out_nomem;
1818
1819                 if (!(data->flags & NFS_MOUNT_NONLM))
1820                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1821                                          NFS_MOUNT_LOCAL_FCNTL);
1822                 else
1823                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1824                                         NFS_MOUNT_LOCAL_FCNTL);
1825                 /*
1826                  * The legacy version 6 binary mount data from userspace has a
1827                  * field used only to transport selinux information into the
1828                  * the kernel.  To continue to support that functionality we
1829                  * have a touch of selinux knowledge here in the NFS code. The
1830                  * userspace code converted context=blah to just blah so we are
1831                  * converting back to the full string selinux understands.
1832                  */
1833                 if (data->context[0]){
1834 #ifdef CONFIG_SECURITY_SELINUX
1835                         int rc;
1836                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1837                         if (!opts_str)
1838                                 return -ENOMEM;
1839                         strcpy(opts_str, "context=");
1840                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1841                         strcat(opts_str, &data->context[0]);
1842                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1843                         kfree(opts_str);
1844                         if (rc)
1845                                 return rc;
1846 #else
1847                         return -EINVAL;
1848 #endif
1849                 }
1850
1851                 break;
1852         default: {
1853                 int status;
1854
1855                 if (nfs_parse_mount_options((char *)options, args) == 0)
1856                         return -EINVAL;
1857
1858                 if (!nfs_verify_server_address(sap))
1859                         goto out_no_address;
1860
1861                 if (args->version == 4)
1862 #ifdef CONFIG_NFS_V4
1863                         return nfs4_validate_text_mount_data(options,
1864                                                              args, dev_name);
1865 #else
1866                         goto out_v4_not_compiled;
1867 #endif
1868
1869                 nfs_set_port(sap, &args->nfs_server.port, 0);
1870
1871                 nfs_set_mount_transport_protocol(args);
1872
1873                 status = nfs_parse_devname(dev_name,
1874                                            &args->nfs_server.hostname,
1875                                            PAGE_SIZE,
1876                                            &args->nfs_server.export_path,
1877                                            NFS_MAXPATHLEN);
1878                 if (!status)
1879                         status = nfs_try_mount(args, mntfh);
1880
1881                 kfree(args->nfs_server.export_path);
1882                 args->nfs_server.export_path = NULL;
1883
1884                 if (status)
1885                         return status;
1886
1887                 break;
1888                 }
1889         }
1890
1891 #ifndef CONFIG_NFS_V3
1892         if (args->version == 3)
1893                 goto out_v3_not_compiled;
1894 #endif /* !CONFIG_NFS_V3 */
1895
1896         return 0;
1897
1898 out_no_data:
1899         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1900         return -EINVAL;
1901
1902 out_no_v3:
1903         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1904                  data->version);
1905         return -EINVAL;
1906
1907 out_no_sec:
1908         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1909         return -EINVAL;
1910
1911 #ifndef CONFIG_NFS_V3
1912 out_v3_not_compiled:
1913         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1914         return -EPROTONOSUPPORT;
1915 #endif /* !CONFIG_NFS_V3 */
1916
1917 #ifndef CONFIG_NFS_V4
1918 out_v4_not_compiled:
1919         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1920         return -EPROTONOSUPPORT;
1921 #endif /* !CONFIG_NFS_V4 */
1922
1923 out_nomem:
1924         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1925         return -ENOMEM;
1926
1927 out_no_address:
1928         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1929         return -EINVAL;
1930
1931 out_invalid_fh:
1932         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1933         return -EINVAL;
1934 }
1935
1936 static int
1937 nfs_compare_remount_data(struct nfs_server *nfss,
1938                          struct nfs_parsed_mount_data *data)
1939 {
1940         if (data->flags != nfss->flags ||
1941             data->rsize != nfss->rsize ||
1942             data->wsize != nfss->wsize ||
1943             data->retrans != nfss->client->cl_timeout->to_retries ||
1944             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1945             data->acregmin != nfss->acregmin / HZ ||
1946             data->acregmax != nfss->acregmax / HZ ||
1947             data->acdirmin != nfss->acdirmin / HZ ||
1948             data->acdirmax != nfss->acdirmax / HZ ||
1949             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1950             data->nfs_server.port != nfss->port ||
1951             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1952             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1953                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1954                 return -EINVAL;
1955
1956         return 0;
1957 }
1958
1959 static int
1960 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1961 {
1962         int error;
1963         struct nfs_server *nfss = sb->s_fs_info;
1964         struct nfs_parsed_mount_data *data;
1965         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1966         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1967         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1968
1969         /*
1970          * Userspace mount programs that send binary options generally send
1971          * them populated with default values. We have no way to know which
1972          * ones were explicitly specified. Fall back to legacy behavior and
1973          * just return success.
1974          */
1975         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1976             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1977                                            options->version <= 6))))
1978                 return 0;
1979
1980         data = kzalloc(sizeof(*data), GFP_KERNEL);
1981         if (data == NULL)
1982                 return -ENOMEM;
1983
1984         /* fill out struct with values from existing mount */
1985         data->flags = nfss->flags;
1986         data->rsize = nfss->rsize;
1987         data->wsize = nfss->wsize;
1988         data->retrans = nfss->client->cl_timeout->to_retries;
1989         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1990         data->acregmin = nfss->acregmin / HZ;
1991         data->acregmax = nfss->acregmax / HZ;
1992         data->acdirmin = nfss->acdirmin / HZ;
1993         data->acdirmax = nfss->acdirmax / HZ;
1994         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1995         data->nfs_server.port = nfss->port;
1996         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1997         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1998                 data->nfs_server.addrlen);
1999
2000         /* overwrite those values with any that were specified */
2001         error = nfs_parse_mount_options((char *)options, data);
2002         if (error < 0)
2003                 goto out;
2004
2005         /*
2006          * noac is a special case. It implies -o sync, but that's not
2007          * necessarily reflected in the mtab options. do_remount_sb
2008          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2009          * remount options, so we have to explicitly reset it.
2010          */
2011         if (data->flags & NFS_MOUNT_NOAC)
2012                 *flags |= MS_SYNCHRONOUS;
2013
2014         /* compare new mount options with old ones */
2015         error = nfs_compare_remount_data(nfss, data);
2016 out:
2017         kfree(data);
2018         return error;
2019 }
2020
2021 /*
2022  * Initialise the common bits of the superblock
2023  */
2024 static inline void nfs_initialise_sb(struct super_block *sb)
2025 {
2026         struct nfs_server *server = NFS_SB(sb);
2027
2028         sb->s_magic = NFS_SUPER_MAGIC;
2029
2030         /* We probably want something more informative here */
2031         snprintf(sb->s_id, sizeof(sb->s_id),
2032                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2033
2034         if (sb->s_blocksize == 0)
2035                 sb->s_blocksize = nfs_block_bits(server->wsize,
2036                                                  &sb->s_blocksize_bits);
2037
2038         if (server->flags & NFS_MOUNT_NOAC)
2039                 sb->s_flags |= MS_SYNCHRONOUS;
2040
2041         sb->s_bdi = &server->backing_dev_info;
2042
2043         nfs_super_set_maxbytes(sb, server->maxfilesize);
2044 }
2045
2046 /*
2047  * Finish setting up an NFS2/3 superblock
2048  */
2049 static void nfs_fill_super(struct super_block *sb,
2050                            struct nfs_parsed_mount_data *data)
2051 {
2052         struct nfs_server *server = NFS_SB(sb);
2053
2054         sb->s_blocksize_bits = 0;
2055         sb->s_blocksize = 0;
2056         if (data->bsize)
2057                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2058
2059         if (server->nfs_client->rpc_ops->version == 3) {
2060                 /* The VFS shouldn't apply the umask to mode bits. We will do
2061                  * so ourselves when necessary.
2062                  */
2063                 sb->s_flags |= MS_POSIXACL;
2064                 sb->s_time_gran = 1;
2065         }
2066
2067         sb->s_op = &nfs_sops;
2068         nfs_initialise_sb(sb);
2069 }
2070
2071 /*
2072  * Finish setting up a cloned NFS2/3 superblock
2073  */
2074 static void nfs_clone_super(struct super_block *sb,
2075                             const struct super_block *old_sb)
2076 {
2077         struct nfs_server *server = NFS_SB(sb);
2078
2079         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2080         sb->s_blocksize = old_sb->s_blocksize;
2081         sb->s_maxbytes = old_sb->s_maxbytes;
2082
2083         if (server->nfs_client->rpc_ops->version == 3) {
2084                 /* The VFS shouldn't apply the umask to mode bits. We will do
2085                  * so ourselves when necessary.
2086                  */
2087                 sb->s_flags |= MS_POSIXACL;
2088                 sb->s_time_gran = 1;
2089         }
2090
2091         sb->s_op = old_sb->s_op;
2092         nfs_initialise_sb(sb);
2093 }
2094
2095 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2096 {
2097         const struct nfs_server *a = s->s_fs_info;
2098         const struct rpc_clnt *clnt_a = a->client;
2099         const struct rpc_clnt *clnt_b = b->client;
2100
2101         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2102                 goto Ebusy;
2103         if (a->nfs_client != b->nfs_client)
2104                 goto Ebusy;
2105         if (a->flags != b->flags)
2106                 goto Ebusy;
2107         if (a->wsize != b->wsize)
2108                 goto Ebusy;
2109         if (a->rsize != b->rsize)
2110                 goto Ebusy;
2111         if (a->acregmin != b->acregmin)
2112                 goto Ebusy;
2113         if (a->acregmax != b->acregmax)
2114                 goto Ebusy;
2115         if (a->acdirmin != b->acdirmin)
2116                 goto Ebusy;
2117         if (a->acdirmax != b->acdirmax)
2118                 goto Ebusy;
2119         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2120                 goto Ebusy;
2121         return 1;
2122 Ebusy:
2123         return 0;
2124 }
2125
2126 struct nfs_sb_mountdata {
2127         struct nfs_server *server;
2128         int mntflags;
2129 };
2130
2131 static int nfs_set_super(struct super_block *s, void *data)
2132 {
2133         struct nfs_sb_mountdata *sb_mntdata = data;
2134         struct nfs_server *server = sb_mntdata->server;
2135         int ret;
2136
2137         s->s_flags = sb_mntdata->mntflags;
2138         s->s_fs_info = server;
2139         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2140         ret = set_anon_super(s, server);
2141         if (ret == 0)
2142                 server->s_dev = s->s_dev;
2143         return ret;
2144 }
2145
2146 static int nfs_compare_super_address(struct nfs_server *server1,
2147                                      struct nfs_server *server2)
2148 {
2149         struct sockaddr *sap1, *sap2;
2150
2151         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2152         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2153
2154         if (sap1->sa_family != sap2->sa_family)
2155                 return 0;
2156
2157         switch (sap1->sa_family) {
2158         case AF_INET: {
2159                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2160                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2161                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2162                         return 0;
2163                 if (sin1->sin_port != sin2->sin_port)
2164                         return 0;
2165                 break;
2166         }
2167         case AF_INET6: {
2168                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2169                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2170                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2171                         return 0;
2172                 if (sin1->sin6_port != sin2->sin6_port)
2173                         return 0;
2174                 break;
2175         }
2176         default:
2177                 return 0;
2178         }
2179
2180         return 1;
2181 }
2182
2183 static int nfs_compare_super(struct super_block *sb, void *data)
2184 {
2185         struct nfs_sb_mountdata *sb_mntdata = data;
2186         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2187         int mntflags = sb_mntdata->mntflags;
2188
2189         if (!nfs_compare_super_address(old, server))
2190                 return 0;
2191         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2192         if (old->flags & NFS_MOUNT_UNSHARED)
2193                 return 0;
2194         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2195                 return 0;
2196         return nfs_compare_mount_options(sb, server, mntflags);
2197 }
2198
2199 static int nfs_bdi_register(struct nfs_server *server)
2200 {
2201         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2202 }
2203
2204 static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2205         int flags, const char *dev_name, void *raw_data)
2206 {
2207         struct nfs_server *server = NULL;
2208         struct super_block *s;
2209         struct nfs_parsed_mount_data *data;
2210         struct nfs_fh *mntfh;
2211         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2212         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2213         struct nfs_sb_mountdata sb_mntdata = {
2214                 .mntflags = flags,
2215         };
2216         int error;
2217
2218         data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
2219         mntfh = nfs_alloc_fhandle();
2220         if (data == NULL || mntfh == NULL)
2221                 goto out_free_fh;
2222
2223         security_init_mnt_opts(&data->lsm_opts);
2224
2225         /* Validate the mount data */
2226         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2227         if (error < 0) {
2228                 mntroot = ERR_PTR(error);
2229                 goto out;
2230         }
2231
2232 #ifdef CONFIG_NFS_V4
2233         if (data->version == 4) {
2234                 mntroot = nfs4_try_mount(flags, dev_name, data);
2235                 kfree(data->client_address);
2236                 kfree(data->nfs_server.export_path);
2237                 goto out;
2238         }
2239 #endif  /* CONFIG_NFS_V4 */
2240
2241         /* Get a volume representation */
2242         server = nfs_create_server(data, mntfh);
2243         if (IS_ERR(server)) {
2244                 mntroot = ERR_CAST(server);
2245                 goto out;
2246         }
2247         sb_mntdata.server = server;
2248
2249         if (server->flags & NFS_MOUNT_UNSHARED)
2250                 compare_super = NULL;
2251
2252         /* Get a superblock - note that we may end up sharing one that already exists */
2253         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2254         if (IS_ERR(s)) {
2255                 mntroot = ERR_CAST(s);
2256                 goto out_err_nosb;
2257         }
2258
2259         if (s->s_fs_info != server) {
2260                 nfs_free_server(server);
2261                 server = NULL;
2262         } else {
2263                 error = nfs_bdi_register(server);
2264                 if (error) {
2265                         mntroot = ERR_PTR(error);
2266                         goto error_splat_bdi;
2267                 }
2268         }
2269
2270         if (!s->s_root) {
2271                 /* initial superblock/root creation */
2272                 nfs_fill_super(s, data);
2273                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2274         }
2275
2276         mntroot = nfs_get_root(s, mntfh, dev_name);
2277         if (IS_ERR(mntroot))
2278                 goto error_splat_super;
2279
2280         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2281         if (error)
2282                 goto error_splat_root;
2283
2284         s->s_flags |= MS_ACTIVE;
2285
2286 out:
2287         kfree(data->nfs_server.hostname);
2288         kfree(data->mount_server.hostname);
2289         kfree(data->fscache_uniq);
2290         security_free_mnt_opts(&data->lsm_opts);
2291 out_free_fh:
2292         nfs_free_fhandle(mntfh);
2293         kfree(data);
2294         return mntroot;
2295
2296 out_err_nosb:
2297         nfs_free_server(server);
2298         goto out;
2299
2300 error_splat_root:
2301         dput(mntroot);
2302         mntroot = ERR_PTR(error);
2303 error_splat_super:
2304         if (server && !s->s_root)
2305                 bdi_unregister(&server->backing_dev_info);
2306 error_splat_bdi:
2307         deactivate_locked_super(s);
2308         goto out;
2309 }
2310
2311 /*
2312  * Ensure that we unregister the bdi before kill_anon_super
2313  * releases the device name
2314  */
2315 static void nfs_put_super(struct super_block *s)
2316 {
2317         struct nfs_server *server = NFS_SB(s);
2318
2319         bdi_unregister(&server->backing_dev_info);
2320 }
2321
2322 /*
2323  * Destroy an NFS2/3 superblock
2324  */
2325 static void nfs_kill_super(struct super_block *s)
2326 {
2327         struct nfs_server *server = NFS_SB(s);
2328
2329         kill_anon_super(s);
2330         nfs_fscache_release_super_cookie(s);
2331         nfs_free_server(server);
2332 }
2333
2334 /*
2335  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2336  */
2337 static struct dentry *
2338 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2339                 const char *dev_name, void *raw_data)
2340 {
2341         struct nfs_clone_mount *data = raw_data;
2342         struct super_block *s;
2343         struct nfs_server *server;
2344         struct dentry *mntroot;
2345         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2346         struct nfs_sb_mountdata sb_mntdata = {
2347                 .mntflags = flags,
2348         };
2349         int error;
2350
2351         dprintk("--> nfs_xdev_mount()\n");
2352
2353         /* create a new volume representation */
2354         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2355         if (IS_ERR(server)) {
2356                 error = PTR_ERR(server);
2357                 goto out_err_noserver;
2358         }
2359         sb_mntdata.server = server;
2360
2361         if (server->flags & NFS_MOUNT_UNSHARED)
2362                 compare_super = NULL;
2363
2364         /* Get a superblock - note that we may end up sharing one that already exists */
2365         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2366         if (IS_ERR(s)) {
2367                 error = PTR_ERR(s);
2368                 goto out_err_nosb;
2369         }
2370
2371         if (s->s_fs_info != server) {
2372                 nfs_free_server(server);
2373                 server = NULL;
2374         } else {
2375                 error = nfs_bdi_register(server);
2376                 if (error)
2377                         goto error_splat_bdi;
2378         }
2379
2380         if (!s->s_root) {
2381                 /* initial superblock/root creation */
2382                 nfs_clone_super(s, data->sb);
2383                 nfs_fscache_get_super_cookie(s, NULL, data);
2384         }
2385
2386         mntroot = nfs_get_root(s, data->fh, dev_name);
2387         if (IS_ERR(mntroot)) {
2388                 error = PTR_ERR(mntroot);
2389                 goto error_splat_super;
2390         }
2391         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2392                 dput(mntroot);
2393                 error = -ESTALE;
2394                 goto error_splat_super;
2395         }
2396
2397         s->s_flags |= MS_ACTIVE;
2398
2399         /* clone any lsm security options from the parent to the new sb */
2400         security_sb_clone_mnt_opts(data->sb, s);
2401
2402         dprintk("<-- nfs_xdev_mount() = 0\n");
2403         return mntroot;
2404
2405 out_err_nosb:
2406         nfs_free_server(server);
2407 out_err_noserver:
2408         dprintk("<-- nfs_xdev_mount() = %d [error]\n", error);
2409         return ERR_PTR(error);
2410
2411 error_splat_super:
2412         if (server && !s->s_root)
2413                 bdi_unregister(&server->backing_dev_info);
2414 error_splat_bdi:
2415         deactivate_locked_super(s);
2416         dprintk("<-- nfs_xdev_mount() = %d [splat]\n", error);
2417         return ERR_PTR(error);
2418 }
2419
2420 #ifdef CONFIG_NFS_V4
2421
2422 /*
2423  * Finish setting up a cloned NFS4 superblock
2424  */
2425 static void nfs4_clone_super(struct super_block *sb,
2426                             const struct super_block *old_sb)
2427 {
2428         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2429         sb->s_blocksize = old_sb->s_blocksize;
2430         sb->s_maxbytes = old_sb->s_maxbytes;
2431         sb->s_time_gran = 1;
2432         sb->s_op = old_sb->s_op;
2433         /*
2434          * The VFS shouldn't apply the umask to mode bits. We will do
2435          * so ourselves when necessary.
2436          */
2437         sb->s_flags  |= MS_POSIXACL;
2438         sb->s_xattr  = old_sb->s_xattr;
2439         nfs_initialise_sb(sb);
2440 }
2441
2442 /*
2443  * Set up an NFS4 superblock
2444  */
2445 static void nfs4_fill_super(struct super_block *sb)
2446 {
2447         sb->s_time_gran = 1;
2448         sb->s_op = &nfs4_sops;
2449         /*
2450          * The VFS shouldn't apply the umask to mode bits. We will do
2451          * so ourselves when necessary.
2452          */
2453         sb->s_flags  |= MS_POSIXACL;
2454         sb->s_xattr = nfs4_xattr_handlers;
2455         nfs_initialise_sb(sb);
2456 }
2457
2458 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2459 {
2460         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2461                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2462 }
2463
2464 static int nfs4_validate_text_mount_data(void *options,
2465                                          struct nfs_parsed_mount_data *args,
2466                                          const char *dev_name)
2467 {
2468         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2469
2470         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2471
2472         nfs_validate_transport_protocol(args);
2473
2474         nfs4_validate_mount_flags(args);
2475
2476         if (args->version != 4) {
2477                 dfprintk(MOUNT,
2478                          "NFS4: Illegal mount version\n");
2479                 return -EINVAL;
2480         }
2481
2482         if (args->auth_flavor_len > 1) {
2483                 dfprintk(MOUNT,
2484                          "NFS4: Too many RPC auth flavours specified\n");
2485                 return -EINVAL;
2486         }
2487
2488         if (args->client_address == NULL) {
2489                 dfprintk(MOUNT,
2490                          "NFS4: mount program didn't pass callback address\n");
2491                 return -EINVAL;
2492         }
2493
2494         return nfs_parse_devname(dev_name,
2495                                    &args->nfs_server.hostname,
2496                                    NFS4_MAXNAMLEN,
2497                                    &args->nfs_server.export_path,
2498                                    NFS4_MAXPATHLEN);
2499 }
2500
2501 /*
2502  * Validate NFSv4 mount options
2503  */
2504 static int nfs4_validate_mount_data(void *options,
2505                                     struct nfs_parsed_mount_data *args,
2506                                     const char *dev_name)
2507 {
2508         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2509         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2510         char *c;
2511
2512         if (data == NULL)
2513                 goto out_no_data;
2514
2515         switch (data->version) {
2516         case 1:
2517                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2518                         goto out_no_address;
2519                 if (data->host_addrlen == 0)
2520                         goto out_no_address;
2521                 args->nfs_server.addrlen = data->host_addrlen;
2522                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2523                         return -EFAULT;
2524                 if (!nfs_verify_server_address(sap))
2525                         goto out_no_address;
2526
2527                 if (data->auth_flavourlen) {
2528                         if (data->auth_flavourlen > 1)
2529                                 goto out_inval_auth;
2530                         if (copy_from_user(&args->auth_flavors[0],
2531                                            data->auth_flavours,
2532                                            sizeof(args->auth_flavors[0])))
2533                                 return -EFAULT;
2534                 }
2535
2536                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2537                 if (IS_ERR(c))
2538                         return PTR_ERR(c);
2539                 args->nfs_server.hostname = c;
2540
2541                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2542                 if (IS_ERR(c))
2543                         return PTR_ERR(c);
2544                 args->nfs_server.export_path = c;
2545                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2546
2547                 c = strndup_user(data->client_addr.data, 16);
2548                 if (IS_ERR(c))
2549                         return PTR_ERR(c);
2550                 args->client_address = c;
2551
2552                 /*
2553                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2554                  * can deal with.
2555                  */
2556
2557                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2558                 args->rsize     = data->rsize;
2559                 args->wsize     = data->wsize;
2560                 args->timeo     = data->timeo;
2561                 args->retrans   = data->retrans;
2562                 args->acregmin  = data->acregmin;
2563                 args->acregmax  = data->acregmax;
2564                 args->acdirmin  = data->acdirmin;
2565                 args->acdirmax  = data->acdirmax;
2566                 args->nfs_server.protocol = data->proto;
2567                 nfs_validate_transport_protocol(args);
2568
2569                 break;
2570         default:
2571                 if (nfs_parse_mount_options((char *)options, args) == 0)
2572                         return -EINVAL;
2573
2574                 if (!nfs_verify_server_address(sap))
2575                         return -EINVAL;
2576
2577                 return nfs4_validate_text_mount_data(options, args, dev_name);
2578         }
2579
2580         return 0;
2581
2582 out_no_data:
2583         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2584         return -EINVAL;
2585
2586 out_inval_auth:
2587         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2588                  data->auth_flavourlen);
2589         return -EINVAL;
2590
2591 out_no_address:
2592         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2593         return -EINVAL;
2594 }
2595
2596 /*
2597  * Get the superblock for the NFS4 root partition
2598  */
2599 static struct dentry *
2600 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
2601                   const char *dev_name, void *raw_data)
2602 {
2603         struct nfs_parsed_mount_data *data = raw_data;
2604         struct super_block *s;
2605         struct nfs_server *server;
2606         struct nfs_fh *mntfh;
2607         struct dentry *mntroot;
2608         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2609         struct nfs_sb_mountdata sb_mntdata = {
2610                 .mntflags = flags,
2611         };
2612         int error = -ENOMEM;
2613
2614         mntfh = nfs_alloc_fhandle();
2615         if (data == NULL || mntfh == NULL)
2616                 goto out_free_fh;
2617
2618         security_init_mnt_opts(&data->lsm_opts);
2619
2620         /* Get a volume representation */
2621         server = nfs4_create_server(data, mntfh);
2622         if (IS_ERR(server)) {
2623                 error = PTR_ERR(server);
2624                 goto out;
2625         }
2626         sb_mntdata.server = server;
2627
2628         if (server->flags & NFS4_MOUNT_UNSHARED)
2629                 compare_super = NULL;
2630
2631         /* Get a superblock - note that we may end up sharing one that already exists */
2632         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2633         if (IS_ERR(s)) {
2634                 error = PTR_ERR(s);
2635                 goto out_free;
2636         }
2637
2638         if (s->s_fs_info != server) {
2639                 nfs_free_server(server);
2640                 server = NULL;
2641         } else {
2642                 error = nfs_bdi_register(server);
2643                 if (error)
2644                         goto error_splat_bdi;
2645         }
2646
2647         if (!s->s_root) {
2648                 /* initial superblock/root creation */
2649                 nfs4_fill_super(s);
2650                 nfs_fscache_get_super_cookie(
2651                         s, data ? data->fscache_uniq : NULL, NULL);
2652         }
2653
2654         mntroot = nfs4_get_root(s, mntfh, dev_name);
2655         if (IS_ERR(mntroot)) {
2656                 error = PTR_ERR(mntroot);
2657                 goto error_splat_super;
2658         }
2659
2660         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2661         if (error)
2662                 goto error_splat_root;
2663
2664         s->s_flags |= MS_ACTIVE;
2665
2666         security_free_mnt_opts(&data->lsm_opts);
2667         nfs_free_fhandle(mntfh);
2668         return mntroot;
2669
2670 out:
2671         security_free_mnt_opts(&data->lsm_opts);
2672 out_free_fh:
2673         nfs_free_fhandle(mntfh);
2674         return ERR_PTR(error);
2675
2676 out_free:
2677         nfs_free_server(server);
2678         goto out;
2679
2680 error_splat_root:
2681         dput(mntroot);
2682 error_splat_super:
2683         if (server && !s->s_root)
2684                 bdi_unregister(&server->backing_dev_info);
2685 error_splat_bdi:
2686         deactivate_locked_super(s);
2687         goto out;
2688 }
2689
2690 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2691                 int flags, void *data, const char *hostname)
2692 {
2693         struct vfsmount *root_mnt;
2694         char *root_devname;
2695         size_t len;
2696
2697         len = strlen(hostname) + 3;
2698         root_devname = kmalloc(len, GFP_KERNEL);
2699         if (root_devname == NULL)
2700                 return ERR_PTR(-ENOMEM);
2701         snprintf(root_devname, len, "%s:/", hostname);
2702         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2703         kfree(root_devname);
2704         return root_mnt;
2705 }
2706
2707 struct nfs_referral_count {
2708         struct list_head list;
2709         const struct task_struct *task;
2710         unsigned int referral_count;
2711 };
2712
2713 static LIST_HEAD(nfs_referral_count_list);
2714 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2715
2716 static struct nfs_referral_count *nfs_find_referral_count(void)
2717 {
2718         struct nfs_referral_count *p;
2719
2720         list_for_each_entry(p, &nfs_referral_count_list, list) {
2721                 if (p->task == current)
2722                         return p;
2723         }
2724         return NULL;
2725 }
2726
2727 #define NFS_MAX_NESTED_REFERRALS 2
2728
2729 static int nfs_referral_loop_protect(void)
2730 {
2731         struct nfs_referral_count *p, *new;
2732         int ret = -ENOMEM;
2733
2734         new = kmalloc(sizeof(*new), GFP_KERNEL);
2735         if (!new)
2736                 goto out;
2737         new->task = current;
2738         new->referral_count = 1;
2739
2740         ret = 0;
2741         spin_lock(&nfs_referral_count_list_lock);
2742         p = nfs_find_referral_count();
2743         if (p != NULL) {
2744                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2745                         ret = -ELOOP;
2746                 else
2747                         p->referral_count++;
2748         } else {
2749                 list_add(&new->list, &nfs_referral_count_list);
2750                 new = NULL;
2751         }
2752         spin_unlock(&nfs_referral_count_list_lock);
2753         kfree(new);
2754 out:
2755         return ret;
2756 }
2757
2758 static void nfs_referral_loop_unprotect(void)
2759 {
2760         struct nfs_referral_count *p;
2761
2762         spin_lock(&nfs_referral_count_list_lock);
2763         p = nfs_find_referral_count();
2764         p->referral_count--;
2765         if (p->referral_count == 0)
2766                 list_del(&p->list);
2767         else
2768                 p = NULL;
2769         spin_unlock(&nfs_referral_count_list_lock);
2770         kfree(p);
2771 }
2772
2773 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
2774                 const char *export_path)
2775 {
2776         struct mnt_namespace *ns_private;
2777         struct super_block *s;
2778         struct dentry *dentry;
2779         struct path path;
2780         int ret;
2781
2782         ns_private = create_mnt_ns(root_mnt);
2783         ret = PTR_ERR(ns_private);
2784         if (IS_ERR(ns_private))
2785                 goto out_mntput;
2786
2787         ret = nfs_referral_loop_protect();
2788         if (ret != 0)
2789                 goto out_put_mnt_ns;
2790
2791         ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
2792                         export_path, LOOKUP_FOLLOW, &path);
2793
2794         nfs_referral_loop_unprotect();
2795         put_mnt_ns(ns_private);
2796
2797         if (ret != 0)
2798                 goto out_err;
2799
2800         s = path.mnt->mnt_sb;
2801         atomic_inc(&s->s_active);
2802         dentry = dget(path.dentry);
2803
2804         path_put(&path);
2805         down_write(&s->s_umount);
2806         return dentry;
2807 out_put_mnt_ns:
2808         put_mnt_ns(ns_private);
2809 out_mntput:
2810         mntput(root_mnt);
2811 out_err:
2812         return ERR_PTR(ret);
2813 }
2814
2815 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
2816                          struct nfs_parsed_mount_data *data)
2817 {
2818         char *export_path;
2819         struct vfsmount *root_mnt;
2820         struct dentry *res;
2821
2822         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2823
2824         export_path = data->nfs_server.export_path;
2825         data->nfs_server.export_path = "/";
2826         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2827                         data->nfs_server.hostname);
2828         data->nfs_server.export_path = export_path;
2829
2830         res = ERR_CAST(root_mnt);
2831         if (!IS_ERR(root_mnt))
2832                 res = nfs_follow_remote_path(root_mnt, export_path);
2833
2834         dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
2835                         IS_ERR(res) ? PTR_ERR(res) : 0,
2836                         IS_ERR(res) ? " [error]" : "");
2837         return res;
2838 }
2839
2840 /*
2841  * Get the superblock for an NFS4 mountpoint
2842  */
2843 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
2844         int flags, const char *dev_name, void *raw_data)
2845 {
2846         struct nfs_parsed_mount_data *data;
2847         int error = -ENOMEM;
2848         struct dentry *res = ERR_PTR(-ENOMEM);
2849
2850         data = nfs_alloc_parsed_mount_data(4);
2851         if (data == NULL)
2852                 goto out_free_data;
2853
2854         /* Validate the mount data */
2855         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2856         if (error < 0) {
2857                 res = ERR_PTR(error);
2858                 goto out;
2859         }
2860
2861         res = nfs4_try_mount(flags, dev_name, data);
2862         if (IS_ERR(res))
2863                 error = PTR_ERR(res);
2864
2865 out:
2866         kfree(data->client_address);
2867         kfree(data->nfs_server.export_path);
2868         kfree(data->nfs_server.hostname);
2869         kfree(data->fscache_uniq);
2870 out_free_data:
2871         kfree(data);
2872         dprintk("<-- nfs4_mount() = %d%s\n", error,
2873                         error != 0 ? " [error]" : "");
2874         return res;
2875 }
2876
2877 static void nfs4_kill_super(struct super_block *sb)
2878 {
2879         struct nfs_server *server = NFS_SB(sb);
2880
2881         dprintk("--> %s\n", __func__);
2882         nfs_super_return_all_delegations(sb);
2883         kill_anon_super(sb);
2884         nfs_fscache_release_super_cookie(sb);
2885         nfs_free_server(server);
2886         dprintk("<-- %s\n", __func__);
2887 }
2888
2889 /*
2890  * Clone an NFS4 server record on xdev traversal (FSID-change)
2891  */
2892 static struct dentry *
2893 nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
2894                  const char *dev_name, void *raw_data)
2895 {
2896         struct nfs_clone_mount *data = raw_data;
2897         struct super_block *s;
2898         struct nfs_server *server;
2899         struct dentry *mntroot;
2900         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2901         struct nfs_sb_mountdata sb_mntdata = {
2902                 .mntflags = flags,
2903         };
2904         int error;
2905
2906         dprintk("--> nfs4_xdev_mount()\n");
2907
2908         /* create a new volume representation */
2909         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2910         if (IS_ERR(server)) {
2911                 error = PTR_ERR(server);
2912                 goto out_err_noserver;
2913         }
2914         sb_mntdata.server = server;
2915
2916         if (server->flags & NFS4_MOUNT_UNSHARED)
2917                 compare_super = NULL;
2918
2919         /* Get a superblock - note that we may end up sharing one that already exists */
2920         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2921         if (IS_ERR(s)) {
2922                 error = PTR_ERR(s);
2923                 goto out_err_nosb;
2924         }
2925
2926         if (s->s_fs_info != server) {
2927                 nfs_free_server(server);
2928                 server = NULL;
2929         } else {
2930                 error = nfs_bdi_register(server);
2931                 if (error)
2932                         goto error_splat_bdi;
2933         }
2934
2935         if (!s->s_root) {
2936                 /* initial superblock/root creation */
2937                 nfs4_clone_super(s, data->sb);
2938                 nfs_fscache_get_super_cookie(s, NULL, data);
2939         }
2940
2941         mntroot = nfs4_get_root(s, data->fh, dev_name);
2942         if (IS_ERR(mntroot)) {
2943                 error = PTR_ERR(mntroot);
2944                 goto error_splat_super;
2945         }
2946         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2947                 dput(mntroot);
2948                 error = -ESTALE;
2949                 goto error_splat_super;
2950         }
2951
2952         s->s_flags |= MS_ACTIVE;
2953
2954         security_sb_clone_mnt_opts(data->sb, s);
2955
2956         dprintk("<-- nfs4_xdev_mount() = 0\n");
2957         return mntroot;
2958
2959 out_err_nosb:
2960         nfs_free_server(server);
2961 out_err_noserver:
2962         dprintk("<-- nfs4_xdev_mount() = %d [error]\n", error);
2963         return ERR_PTR(error);
2964
2965 error_splat_super:
2966         if (server && !s->s_root)
2967                 bdi_unregister(&server->backing_dev_info);
2968 error_splat_bdi:
2969         deactivate_locked_super(s);
2970         dprintk("<-- nfs4_xdev_mount() = %d [splat]\n", error);
2971         return ERR_PTR(error);
2972 }
2973
2974 static struct dentry *
2975 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
2976                            const char *dev_name, void *raw_data)
2977 {
2978         struct nfs_clone_mount *data = raw_data;
2979         struct super_block *s;
2980         struct nfs_server *server;
2981         struct dentry *mntroot;
2982         struct nfs_fh *mntfh;
2983         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2984         struct nfs_sb_mountdata sb_mntdata = {
2985                 .mntflags = flags,
2986         };
2987         int error = -ENOMEM;
2988
2989         dprintk("--> nfs4_referral_get_sb()\n");
2990
2991         mntfh = nfs_alloc_fhandle();
2992         if (mntfh == NULL)
2993                 goto out_err_nofh;
2994
2995         /* create a new volume representation */
2996         server = nfs4_create_referral_server(data, mntfh);
2997         if (IS_ERR(server)) {
2998                 error = PTR_ERR(server);
2999                 goto out_err_noserver;
3000         }
3001         sb_mntdata.server = server;
3002
3003         if (server->flags & NFS4_MOUNT_UNSHARED)
3004                 compare_super = NULL;
3005
3006         /* Get a superblock - note that we may end up sharing one that already exists */
3007         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
3008         if (IS_ERR(s)) {
3009                 error = PTR_ERR(s);
3010                 goto out_err_nosb;
3011         }
3012
3013         if (s->s_fs_info != server) {
3014                 nfs_free_server(server);
3015                 server = NULL;
3016         } else {
3017                 error = nfs_bdi_register(server);
3018                 if (error)
3019                         goto error_splat_bdi;
3020         }
3021
3022         if (!s->s_root) {
3023                 /* initial superblock/root creation */
3024                 nfs4_fill_super(s);
3025                 nfs_fscache_get_super_cookie(s, NULL, data);
3026         }
3027
3028         mntroot = nfs4_get_root(s, mntfh, dev_name);
3029         if (IS_ERR(mntroot)) {
3030                 error = PTR_ERR(mntroot);
3031                 goto error_splat_super;
3032         }
3033         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3034                 dput(mntroot);
3035                 error = -ESTALE;
3036                 goto error_splat_super;
3037         }
3038
3039         s->s_flags |= MS_ACTIVE;
3040
3041         security_sb_clone_mnt_opts(data->sb, s);
3042
3043         nfs_free_fhandle(mntfh);
3044         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3045         return mntroot;
3046
3047 out_err_nosb:
3048         nfs_free_server(server);
3049 out_err_noserver:
3050         nfs_free_fhandle(mntfh);
3051 out_err_nofh:
3052         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3053         return ERR_PTR(error);
3054
3055 error_splat_super:
3056         if (server && !s->s_root)
3057                 bdi_unregister(&server->backing_dev_info);
3058 error_splat_bdi:
3059         deactivate_locked_super(s);
3060         nfs_free_fhandle(mntfh);
3061         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3062         return ERR_PTR(error);
3063 }
3064
3065 /*
3066  * Create an NFS4 server record on referral traversal
3067  */
3068 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
3069                 int flags, const char *dev_name, void *raw_data)
3070 {
3071         struct nfs_clone_mount *data = raw_data;
3072         char *export_path;
3073         struct vfsmount *root_mnt;
3074         struct dentry *res;
3075
3076         dprintk("--> nfs4_referral_mount()\n");
3077
3078         export_path = data->mnt_path;
3079         data->mnt_path = "/";
3080
3081         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3082                         flags, data, data->hostname);
3083         data->mnt_path = export_path;
3084
3085         res = ERR_CAST(root_mnt);
3086         if (!IS_ERR(root_mnt))
3087                 res = nfs_follow_remote_path(root_mnt, export_path);
3088         dprintk("<-- nfs4_referral_mount() = %ld%s\n",
3089                         IS_ERR(res) ? PTR_ERR(res) : 0,
3090                         IS_ERR(res) ? " [error]" : "");
3091         return res;
3092 }
3093
3094 #endif /* CONFIG_NFS_V4 */