Pileus Git - ~andy/linux/blob - fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/seq_file.h>
  43 #include <linux/mount.h>
  44 #include <linux/namei.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56
  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_udp, Opt_tcp, Opt_rdma,
  84         Opt_acl, Opt_noacl,
  85         Opt_rdirplus, Opt_nordirplus,
  86         Opt_sharecache, Opt_nosharecache,
  87         Opt_resvport, Opt_noresvport,
  88         Opt_fscache, Opt_nofscache,
  89
  90         /* Mount options that take integer arguments */
  91         Opt_port,
  92         Opt_rsize, Opt_wsize, Opt_bsize,
  93         Opt_timeo, Opt_retrans,
  94         Opt_acregmin, Opt_acregmax,
  95         Opt_acdirmin, Opt_acdirmax,
  96         Opt_actimeo,
  97         Opt_namelen,
  98         Opt_mountport,
  99         Opt_mountvers,
 100         Opt_minorversion,
 101
 102         /* Mount options that take string arguments */
 103         Opt_nfsvers,
 104         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 105         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 106         Opt_lookupcache,
 107         Opt_fscache_uniq,
 108         Opt_local_lock,
 109
 110         /* Special mount options */
 111         Opt_userspace, Opt_deprecated, Opt_sloppy,
 112
 113         Opt_err
 114 };
 115
 116 static const match_table_t nfs_mount_option_tokens = {
 117         { Opt_userspace, "bg" },
 118         { Opt_userspace, "fg" },
 119         { Opt_userspace, "retry=%s" },
 120
 121         { Opt_sloppy, "sloppy" },
 122
 123         { Opt_soft, "soft" },
 124         { Opt_hard, "hard" },
 125         { Opt_deprecated, "intr" },
 126         { Opt_deprecated, "nointr" },
 127         { Opt_posix, "posix" },
 128         { Opt_noposix, "noposix" },
 129         { Opt_cto, "cto" },
 130         { Opt_nocto, "nocto" },
 131         { Opt_ac, "ac" },
 132         { Opt_noac, "noac" },
 133         { Opt_lock, "lock" },
 134         { Opt_nolock, "nolock" },
 135         { Opt_udp, "udp" },
 136         { Opt_tcp, "tcp" },
 137         { Opt_rdma, "rdma" },
 138         { Opt_acl, "acl" },
 139         { Opt_noacl, "noacl" },
 140         { Opt_rdirplus, "rdirplus" },
 141         { Opt_nordirplus, "nordirplus" },
 142         { Opt_sharecache, "sharecache" },
 143         { Opt_nosharecache, "nosharecache" },
 144         { Opt_resvport, "resvport" },
 145         { Opt_noresvport, "noresvport" },
 146         { Opt_fscache, "fsc" },
 147         { Opt_nofscache, "nofsc" },
 148
 149         { Opt_port, "port=%s" },
 150         { Opt_rsize, "rsize=%s" },
 151         { Opt_wsize, "wsize=%s" },
 152         { Opt_bsize, "bsize=%s" },
 153         { Opt_timeo, "timeo=%s" },
 154         { Opt_retrans, "retrans=%s" },
 155         { Opt_acregmin, "acregmin=%s" },
 156         { Opt_acregmax, "acregmax=%s" },
 157         { Opt_acdirmin, "acdirmin=%s" },
 158         { Opt_acdirmax, "acdirmax=%s" },
 159         { Opt_actimeo, "actimeo=%s" },
 160         { Opt_namelen, "namlen=%s" },
 161         { Opt_mountport, "mountport=%s" },
 162         { Opt_mountvers, "mountvers=%s" },
 163         { Opt_minorversion, "minorversion=%s" },
 164
 165         { Opt_nfsvers, "nfsvers=%s" },
 166         { Opt_nfsvers, "vers=%s" },
 167
 168         { Opt_sec, "sec=%s" },
 169         { Opt_proto, "proto=%s" },
 170         { Opt_mountproto, "mountproto=%s" },
 171         { Opt_addr, "addr=%s" },
 172         { Opt_clientaddr, "clientaddr=%s" },
 173         { Opt_mounthost, "mounthost=%s" },
 174         { Opt_mountaddr, "mountaddr=%s" },
 175
 176         { Opt_lookupcache, "lookupcache=%s" },
 177         { Opt_fscache_uniq, "fsc=%s" },
 178         { Opt_local_lock, "local_lock=%s" },
 179
 180         /* The following needs to be listed after all other options */
 181         { Opt_nfsvers, "v%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 enum {
 264         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 265         Opt_vers_4_1,
 266
 267         Opt_vers_err
 268 };
 269
 270 static match_table_t nfs_vers_tokens = {
 271         { Opt_vers_2, "2" },
 272         { Opt_vers_3, "3" },
 273         { Opt_vers_4, "4" },
 274         { Opt_vers_4_0, "4.0" },
 275         { Opt_vers_4_1, "4.1" },
 276
 277         { Opt_vers_err, NULL }
 278 };
 279
 280 static void nfs_umount_begin(struct super_block *);
 281 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 282 static int  nfs_show_options(struct seq_file *, struct dentry *);
 283 static int  nfs_show_devname(struct seq_file *, struct dentry *);
 284 static int  nfs_show_path(struct seq_file *, struct dentry *);
 285 static int  nfs_show_stats(struct seq_file *, struct dentry *);
 286 static struct dentry *nfs_fs_mount(struct file_system_type *,
 287                 int, const char *, void *);
 288 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 289                 int flags, const char *dev_name, void *raw_data);
 290 static void nfs_put_super(struct super_block *);
 291 static void nfs_kill_super(struct super_block *);
 292 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 293
 294 static struct file_system_type nfs_fs_type = {
 295         .owner          = THIS_MODULE,
 296         .name           = "nfs",
 297         .mount          = nfs_fs_mount,
 298         .kill_sb        = nfs_kill_super,
 299         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 300 };
 301
 302 struct file_system_type nfs_xdev_fs_type = {
 303         .owner          = THIS_MODULE,
 304         .name           = "nfs",
 305         .mount          = nfs_xdev_mount,
 306         .kill_sb        = nfs_kill_super,
 307         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 308 };
 309
 310 static const struct super_operations nfs_sops = {
 311         .alloc_inode    = nfs_alloc_inode,
 312         .destroy_inode  = nfs_destroy_inode,
 313         .write_inode    = nfs_write_inode,
 314         .put_super      = nfs_put_super,
 315         .statfs         = nfs_statfs,
 316         .evict_inode    = nfs_evict_inode,
 317         .umount_begin   = nfs_umount_begin,
 318         .show_options   = nfs_show_options,
 319         .show_devname   = nfs_show_devname,
 320         .show_path      = nfs_show_path,
 321         .show_stats     = nfs_show_stats,
 322         .remount_fs     = nfs_remount,
 323 };
 324
 325 #ifdef CONFIG_NFS_V4
 326 static int nfs4_validate_text_mount_data(void *options,
 327         struct nfs_parsed_mount_data *args, const char *dev_name);
 328 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
 329         struct nfs_parsed_mount_data *data);
 330 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
 331         int flags, const char *dev_name, void *raw_data);
 332 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
 333         int flags, const char *dev_name, void *raw_data);
 334 static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
 335         int flags, const char *dev_name, void *raw_data);
 336 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
 337         int flags, const char *dev_name, void *raw_data);
 338 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
 339         int flags, const char *dev_name, void *raw_data);
 340 static void nfs4_kill_super(struct super_block *sb);
 341
 342 static struct file_system_type nfs4_fs_type = {
 343         .owner          = THIS_MODULE,
 344         .name           = "nfs4",
 345         .mount          = nfs4_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_fs_type = {
 351         .owner          = THIS_MODULE,
 352         .name           = "nfs4",
 353         .mount          = nfs4_remote_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_xdev_fs_type = {
 359         .owner          = THIS_MODULE,
 360         .name           = "nfs4",
 361         .mount          = nfs4_xdev_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 struct file_system_type nfs4_remote_referral_fs_type = {
 367         .owner          = THIS_MODULE,
 368         .name           = "nfs4",
 369         .mount          = nfs4_remote_referral_mount,
 370         .kill_sb        = nfs4_kill_super,
 371         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 372 };
 373
 374 struct file_system_type nfs4_referral_fs_type = {
 375         .owner          = THIS_MODULE,
 376         .name           = "nfs4",
 377         .mount          = nfs4_referral_mount,
 378         .kill_sb        = nfs4_kill_super,
 379         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 380 };
 381
 382 static const struct super_operations nfs4_sops = {
 383         .alloc_inode    = nfs_alloc_inode,
 384         .destroy_inode  = nfs_destroy_inode,
 385         .write_inode    = nfs_write_inode,
 386         .put_super      = nfs_put_super,
 387         .statfs         = nfs_statfs,
 388         .evict_inode    = nfs4_evict_inode,
 389         .umount_begin   = nfs_umount_begin,
 390         .show_options   = nfs_show_options,
 391         .show_devname   = nfs_show_devname,
 392         .show_path      = nfs_show_path,
 393         .show_stats     = nfs_show_stats,
 394         .remount_fs     = nfs_remount,
 395 };
 396 #endif
 397
 398 static struct shrinker acl_shrinker = {
 399         .shrink         = nfs_access_cache_shrinker,
 400         .seeks          = DEFAULT_SEEKS,
 401 };
 402
 403 /*
 404  * Register the NFS filesystems
 405  */
 406 int __init register_nfs_fs(void)
 407 {
 408         int ret;
 409
 410         ret = register_filesystem(&nfs_fs_type);
 411         if (ret < 0)
 412                 goto error_0;
 413
 414         ret = nfs_register_sysctl();
 415         if (ret < 0)
 416                 goto error_1;
 417 #ifdef CONFIG_NFS_V4
 418         ret = register_filesystem(&nfs4_fs_type);
 419         if (ret < 0)
 420                 goto error_2;
 421 #endif
 422         register_shrinker(&acl_shrinker);
 423         return 0;
 424
 425 #ifdef CONFIG_NFS_V4
 426 error_2:
 427         nfs_unregister_sysctl();
 428 #endif
 429 error_1:
 430         unregister_filesystem(&nfs_fs_type);
 431 error_0:
 432         return ret;
 433 }
 434
 435 /*
 436  * Unregister the NFS filesystems
 437  */
 438 void __exit unregister_nfs_fs(void)
 439 {
 440         unregister_shrinker(&acl_shrinker);
 441 #ifdef CONFIG_NFS_V4
 442         unregister_filesystem(&nfs4_fs_type);
 443 #endif
 444         nfs_unregister_sysctl();
 445         unregister_filesystem(&nfs_fs_type);
 446 }
 447
 448 void nfs_sb_active(struct super_block *sb)
 449 {
 450         struct nfs_server *server = NFS_SB(sb);
 451
 452         if (atomic_inc_return(&server->active) == 1)
 453                 atomic_inc(&sb->s_active);
 454 }
 455
 456 void nfs_sb_deactive(struct super_block *sb)
 457 {
 458         struct nfs_server *server = NFS_SB(sb);
 459
 460         if (atomic_dec_and_test(&server->active))
 461                 deactivate_super(sb);
 462 }
 463
 464 /*
 465  * Deliver file system statistics to userspace
 466  */
 467 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 468 {
 469         struct nfs_server *server = NFS_SB(dentry->d_sb);
 470         unsigned char blockbits;
 471         unsigned long blockres;
 472         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 473         struct nfs_fsstat res;
 474         int error = -ENOMEM;
 475
 476         res.fattr = nfs_alloc_fattr();
 477         if (res.fattr == NULL)
 478                 goto out_err;
 479
 480         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 481         if (unlikely(error == -ESTALE)) {
 482                 struct dentry *pd_dentry;
 483
 484                 pd_dentry = dget_parent(dentry);
 485                 if (pd_dentry != NULL) {
 486                         nfs_zap_caches(pd_dentry->d_inode);
 487                         dput(pd_dentry);
 488                 }
 489         }
 490         nfs_free_fattr(res.fattr);
 491         if (error < 0)
 492                 goto out_err;
 493
 494         buf->f_type = NFS_SUPER_MAGIC;
 495
 496         /*
 497          * Current versions of glibc do not correctly handle the
 498          * case where f_frsize != f_bsize.  Eventually we want to
 499          * report the value of wtmult in this field.
 500          */
 501         buf->f_frsize = dentry->d_sb->s_blocksize;
 502
 503         /*
 504          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 505          * are reported in units of f_frsize.  Linux hasn't had
 506          * an f_frsize field in its statfs struct until recently,
 507          * thus historically Linux's sys_statfs reports these
 508          * fields in units of f_bsize.
 509          */
 510         buf->f_bsize = dentry->d_sb->s_blocksize;
 511         blockbits = dentry->d_sb->s_blocksize_bits;
 512         blockres = (1 << blockbits) - 1;
 513         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 514         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 515         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 516
 517         buf->f_files = res.tfiles;
 518         buf->f_ffree = res.afiles;
 519
 520         buf->f_namelen = server->namelen;
 521
 522         return 0;
 523
 524  out_err:
 525         dprintk("%s: statfs error = %d\n", __func__, -error);
 526         return error;
 527 }
 528
 529 /*
 530  * Map the security flavour number to a name
 531  */
 532 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 533 {
 534         static const struct {
 535                 rpc_authflavor_t flavour;
 536                 const char *str;
 537         } sec_flavours[] = {
 538                 { RPC_AUTH_NULL, "null" },
 539                 { RPC_AUTH_UNIX, "sys" },
 540                 { RPC_AUTH_GSS_KRB5, "krb5" },
 541                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 542                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 543                 { RPC_AUTH_GSS_LKEY, "lkey" },
 544                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 545                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 546                 { RPC_AUTH_GSS_SPKM, "spkm" },
 547                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 548                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 549                 { UINT_MAX, "unknown" }
 550         };
 551         int i;
 552
 553         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 554                 if (sec_flavours[i].flavour == flavour)
 555                         break;
 556         }
 557         return sec_flavours[i].str;
 558 }
 559
 560 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 561                                   int showdefaults)
 562 {
 563         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 564
 565         seq_printf(m, ",mountproto=");
 566         switch (sap->sa_family) {
 567         case AF_INET:
 568                 switch (nfss->mountd_protocol) {
 569                 case IPPROTO_UDP:
 570                         seq_printf(m, RPCBIND_NETID_UDP);
 571                         break;
 572                 case IPPROTO_TCP:
 573                         seq_printf(m, RPCBIND_NETID_TCP);
 574                         break;
 575                 default:
 576                         if (showdefaults)
 577                                 seq_printf(m, "auto");
 578                 }
 579                 break;
 580         case AF_INET6:
 581                 switch (nfss->mountd_protocol) {
 582                 case IPPROTO_UDP:
 583                         seq_printf(m, RPCBIND_NETID_UDP6);
 584                         break;
 585                 case IPPROTO_TCP:
 586                         seq_printf(m, RPCBIND_NETID_TCP6);
 587                         break;
 588                 default:
 589                         if (showdefaults)
 590                                 seq_printf(m, "auto");
 591                 }
 592                 break;
 593         default:
 594                 if (showdefaults)
 595                         seq_printf(m, "auto");
 596         }
 597 }
 598
 599 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 600                                     int showdefaults)
 601 {
 602         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 603
 604         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 605                 return;
 606
 607         switch (sap->sa_family) {
 608         case AF_INET: {
 609                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 610                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 611                 break;
 612         }
 613         case AF_INET6: {
 614                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 615                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 616                 break;
 617         }
 618         default:
 619                 if (showdefaults)
 620                         seq_printf(m, ",mountaddr=unspecified");
 621         }
 622
 623         if (nfss->mountd_version || showdefaults)
 624                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 625         if ((nfss->mountd_port &&
 626                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 627                 showdefaults)
 628                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 629
 630         nfs_show_mountd_netid(m, nfss, showdefaults);
 631 }
 632
 633 #ifdef CONFIG_NFS_V4
 634 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 635                                     int showdefaults)
 636 {
 637         struct nfs_client *clp = nfss->nfs_client;
 638
 639         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 640 }
 641 #else
 642 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 643                                     int showdefaults)
 644 {
 645 }
 646 #endif
 647
 648 static void nfs_show_nfs_version(struct seq_file *m,
 649                 unsigned int version,
 650                 unsigned int minorversion)
 651 {
 652         seq_printf(m, ",vers=%u", version);
 653         if (version == 4)
 654                 seq_printf(m, ".%u", minorversion);
 655 }
 656
 657 /*
 658  * Describe the mount options in force on this server representation
 659  */
 660 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 661                                    int showdefaults)
 662 {
 663         static const struct proc_nfs_info {
 664                 int flag;
 665                 const char *str;
 666                 const char *nostr;
 667         } nfs_info[] = {
 668                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 669                 { NFS_MOUNT_POSIX, ",posix", "" },
 670                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 671                 { NFS_MOUNT_NOAC, ",noac", "" },
 672                 { NFS_MOUNT_NONLM, ",nolock", "" },
 673                 { NFS_MOUNT_NOACL, ",noacl", "" },
 674                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 675                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 676                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 677                 { 0, NULL, NULL }
 678         };
 679         const struct proc_nfs_info *nfs_infop;
 680         struct nfs_client *clp = nfss->nfs_client;
 681         u32 version = clp->rpc_ops->version;
 682         int local_flock, local_fcntl;
 683
 684         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 685         seq_printf(m, ",rsize=%u", nfss->rsize);
 686         seq_printf(m, ",wsize=%u", nfss->wsize);
 687         if (nfss->bsize != 0)
 688                 seq_printf(m, ",bsize=%u", nfss->bsize);
 689         seq_printf(m, ",namlen=%u", nfss->namelen);
 690         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 691                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 692         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 693                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 694         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 695                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 696         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 697                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 698         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 699                 if (nfss->flags & nfs_infop->flag)
 700                         seq_puts(m, nfs_infop->str);
 701                 else
 702                         seq_puts(m, nfs_infop->nostr);
 703         }
 704         seq_printf(m, ",proto=%s",
 705                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 706         if (version == 4) {
 707                 if (nfss->port != NFS_PORT)
 708                         seq_printf(m, ",port=%u", nfss->port);
 709         } else
 710                 if (nfss->port)
 711                         seq_printf(m, ",port=%u", nfss->port);
 712
 713         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 714         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 715         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 716
 717         if (version != 4)
 718                 nfs_show_mountd_options(m, nfss, showdefaults);
 719         else
 720                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 721
 722         if (nfss->options & NFS_OPTION_FSCACHE)
 723                 seq_printf(m, ",fsc");
 724
 725         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 726                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 727                         seq_printf(m, ",lookupcache=none");
 728                 else
 729                         seq_printf(m, ",lookupcache=pos");
 730         }
 731
 732         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 733         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 734
 735         if (!local_flock && !local_fcntl)
 736                 seq_printf(m, ",local_lock=none");
 737         else if (local_flock && local_fcntl)
 738                 seq_printf(m, ",local_lock=all");
 739         else if (local_flock)
 740                 seq_printf(m, ",local_lock=flock");
 741         else
 742                 seq_printf(m, ",local_lock=posix");
 743 }
 744
 745 /*
 746  * Describe the mount options on this VFS mountpoint
 747  */
 748 static int nfs_show_options(struct seq_file *m, struct dentry *root)
 749 {
 750         struct nfs_server *nfss = NFS_SB(root->d_sb);
 751
 752         nfs_show_mount_options(m, nfss, 0);
 753
 754         seq_printf(m, ",addr=%s",
 755                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 756                                                         RPC_DISPLAY_ADDR));
 757
 758         return 0;
 759 }
 760
 761 #ifdef CONFIG_NFS_V4
 762 #ifdef CONFIG_NFS_V4_1
 763 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 764 {
 765         if (nfs4_has_session(server->nfs_client))
 766                 seq_printf(m, ",sessions");
 767 }
 768 #else
 769 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 770 #endif
 771 #endif
 772
 773 #ifdef CONFIG_NFS_V4
 774 #ifdef CONFIG_NFS_V4_1
 775 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 776 {
 777         seq_printf(m, ",pnfs=");
 778         if (server->pnfs_curr_ld)
 779                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 780         else
 781                 seq_printf(m, "not configured");
 782 }
 783 #else
 784 static void show_pnfs(struct seq_file *m, struct nfs_server *server) {}
 785 #endif
 786 #endif
 787
 788 static int nfs_show_devname(struct seq_file *m, struct dentry *root)
 789 {
 790         char *page = (char *) __get_free_page(GFP_KERNEL);
 791         char *devname, *dummy;
 792         int err = 0;
 793         if (!page)
 794                 return -ENOMEM;
 795         devname = nfs_path(&dummy, root, page, PAGE_SIZE);
 796         if (IS_ERR(devname))
 797                 err = PTR_ERR(devname);
 798         else
 799                 seq_escape(m, devname, " \t\n\\");
 800         free_page((unsigned long)page);
 801         return err;
 802 }
 803
 804 static int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 805 {
 806         seq_puts(m, "/");
 807         return 0;
 808 }
 809
 810 /*
 811  * Present statistical information for this VFS mountpoint
 812  */
 813 static int nfs_show_stats(struct seq_file *m, struct dentry *root)
 814 {
 815         int i, cpu;
 816         struct nfs_server *nfss = NFS_SB(root->d_sb);
 817         struct rpc_auth *auth = nfss->client->cl_auth;
 818         struct nfs_iostats totals = { };
 819
 820         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 821
 822         /*
 823          * Display all mount option settings
 824          */
 825         seq_printf(m, "\n\topts:\t");
 826         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 827         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 828         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 829         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 830         nfs_show_mount_options(m, nfss, 1);
 831
 832         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 833
 834         if (nfss->nfs_client && nfss->nfs_client->impl_id) {
 835                 struct nfs41_impl_id *impl_id = nfss->nfs_client->impl_id;
 836                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 837                            "date='%llu,%u'",
 838                            impl_id->name, impl_id->domain,
 839                            impl_id->date.seconds, impl_id->date.nseconds);
 840         }
 841
 842         seq_printf(m, "\n\tcaps:\t");
 843         seq_printf(m, "caps=0x%x", nfss->caps);
 844         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 845         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 846         seq_printf(m, ",bsize=%u", nfss->bsize);
 847         seq_printf(m, ",namlen=%u", nfss->namelen);
 848
 849 #ifdef CONFIG_NFS_V4
 850         if (nfss->nfs_client->rpc_ops->version == 4) {
 851                 seq_printf(m, "\n\tnfsv4:\t");
 852                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 853                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 854                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 855                 show_sessions(m, nfss);
 856                 show_pnfs(m, nfss);
 857         }
 858 #endif
 859
 860         /*
 861          * Display security flavor in effect for this mount
 862          */
 863         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 864         if (auth->au_flavor)
 865                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 866
 867         /*
 868          * Display superblock I/O counters
 869          */
 870         for_each_possible_cpu(cpu) {
 871                 struct nfs_iostats *stats;
 872
 873                 preempt_disable();
 874                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 875
 876                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 877                         totals.events[i] += stats->events[i];
 878                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 879                         totals.bytes[i] += stats->bytes[i];
 880 #ifdef CONFIG_NFS_FSCACHE
 881                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 882                         totals.fscache[i] += stats->fscache[i];
 883 #endif
 884
 885                 preempt_enable();
 886         }
 887
 888         seq_printf(m, "\n\tevents:\t");
 889         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 890                 seq_printf(m, "%lu ", totals.events[i]);
 891         seq_printf(m, "\n\tbytes:\t");
 892         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 893                 seq_printf(m, "%Lu ", totals.bytes[i]);
 894 #ifdef CONFIG_NFS_FSCACHE
 895         if (nfss->options & NFS_OPTION_FSCACHE) {
 896                 seq_printf(m, "\n\tfsc:\t");
 897                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 898                         seq_printf(m, "%Lu ", totals.bytes[i]);
 899         }
 900 #endif
 901         seq_printf(m, "\n");
 902
 903         rpc_print_iostats(m, nfss->client);
 904
 905         return 0;
 906 }
 907
 908 /*
 909  * Begin unmount by attempting to remove all automounted mountpoints we added
 910  * in response to xdev traversals and referrals
 911  */
 912 static void nfs_umount_begin(struct super_block *sb)
 913 {
 914         struct nfs_server *server;
 915         struct rpc_clnt *rpc;
 916
 917         server = NFS_SB(sb);
 918         /* -EIO all pending I/O */
 919         rpc = server->client_acl;
 920         if (!IS_ERR(rpc))
 921                 rpc_killall_tasks(rpc);
 922         rpc = server->client;
 923         if (!IS_ERR(rpc))
 924                 rpc_killall_tasks(rpc);
 925 }
 926
 927 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
 928 {
 929         struct nfs_parsed_mount_data *data;
 930
 931         data = kzalloc(sizeof(*data), GFP_KERNEL);
 932         if (data) {
 933                 data->acregmin          = NFS_DEF_ACREGMIN;
 934                 data->acregmax          = NFS_DEF_ACREGMAX;
 935                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 936                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 937                 data->mount_server.port = NFS_UNSPEC_PORT;
 938                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 939                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 940                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 941                 data->auth_flavor_len   = 1;
 942                 data->version           = version;
 943                 data->minorversion      = 0;
 944                 data->net               = current->nsproxy->net_ns;
 945                 security_init_mnt_opts(&data->lsm_opts);
 946         }
 947         return data;
 948 }
 949
 950 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 951 {
 952         if (data) {
 953                 kfree(data->client_address);
 954                 kfree(data->mount_server.hostname);
 955                 kfree(data->nfs_server.export_path);
 956                 kfree(data->nfs_server.hostname);
 957                 kfree(data->fscache_uniq);
 958                 security_free_mnt_opts(&data->lsm_opts);
 959                 kfree(data);
 960         }
 961 }
 962
 963 /*
 964  * Sanity-check a server address provided by the mount command.
 965  *
 966  * Address family must be initialized, and address must not be
 967  * the ANY address for that family.
 968  */
 969 static int nfs_verify_server_address(struct sockaddr *addr)
 970 {
 971         switch (addr->sa_family) {
 972         case AF_INET: {
 973                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 974                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 975         }
 976         case AF_INET6: {
 977                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 978                 return !ipv6_addr_any(sa);
 979         }
 980         }
 981
 982         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 983         return 0;
 984 }
 985
 986 /*
 987  * Select between a default port value and a user-specified port value.
 988  * If a zero value is set, then autobind will be used.
 989  */
 990 static void nfs_set_port(struct sockaddr *sap, int *port,
 991                                  const unsigned short default_port)
 992 {
 993         if (*port == NFS_UNSPEC_PORT)
 994                 *port = default_port;
 995
 996         rpc_set_port(sap, *port);
 997 }
 998
 999 /*
1000  * Sanity check the NFS transport protocol.
1001  *
1002  */
1003 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
1004 {
1005         switch (mnt->nfs_server.protocol) {
1006         case XPRT_TRANSPORT_UDP:
1007         case XPRT_TRANSPORT_TCP:
1008         case XPRT_TRANSPORT_RDMA:
1009                 break;
1010         default:
1011                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1012         }
1013 }
1014
1015 /*
1016  * For text based NFSv2/v3 mounts, the mount protocol transport default
1017  * settings should depend upon the specified NFS transport.
1018  */
1019 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1020 {
1021         nfs_validate_transport_protocol(mnt);
1022
1023         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1024             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1025                         return;
1026         switch (mnt->nfs_server.protocol) {
1027         case XPRT_TRANSPORT_UDP:
1028                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1029                 break;
1030         case XPRT_TRANSPORT_TCP:
1031         case XPRT_TRANSPORT_RDMA:
1032                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1033         }
1034 }
1035
1036 /*
1037  * Parse the value of the 'sec=' option.
1038  */
1039 static int nfs_parse_security_flavors(char *value,
1040                                       struct nfs_parsed_mount_data *mnt)
1041 {
1042         substring_t args[MAX_OPT_ARGS];
1043
1044         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1045
1046         switch (match_token(value, nfs_secflavor_tokens, args)) {
1047         case Opt_sec_none:
1048                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1049                 break;
1050         case Opt_sec_sys:
1051                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1052                 break;
1053         case Opt_sec_krb5:
1054                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1055                 break;
1056         case Opt_sec_krb5i:
1057                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1058                 break;
1059         case Opt_sec_krb5p:
1060                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1061                 break;
1062         case Opt_sec_lkey:
1063                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1064                 break;
1065         case Opt_sec_lkeyi:
1066                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1067                 break;
1068         case Opt_sec_lkeyp:
1069                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1070                 break;
1071         case Opt_sec_spkm:
1072                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1073                 break;
1074         case Opt_sec_spkmi:
1075                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1076                 break;
1077         case Opt_sec_spkmp:
1078                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1079                 break;
1080         default:
1081                 return 0;
1082         }
1083
1084         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1085         mnt->auth_flavor_len = 1;
1086         return 1;
1087 }
1088
1089 static int nfs_parse_version_string(char *string,
1090                 struct nfs_parsed_mount_data *mnt,
1091                 substring_t *args)
1092 {
1093         mnt->flags &= ~NFS_MOUNT_VER3;
1094         switch (match_token(string, nfs_vers_tokens, args)) {
1095         case Opt_vers_2:
1096                 mnt->version = 2;
1097                 break;
1098         case Opt_vers_3:
1099                 mnt->flags |= NFS_MOUNT_VER3;
1100                 mnt->version = 3;
1101                 break;
1102         case Opt_vers_4:
1103                 /* Backward compatibility option. In future,
1104                  * the mount program should always supply
1105                  * a NFSv4 minor version number.
1106                  */
1107                 mnt->version = 4;
1108                 break;
1109         case Opt_vers_4_0:
1110                 mnt->version = 4;
1111                 mnt->minorversion = 0;
1112                 break;
1113         case Opt_vers_4_1:
1114                 mnt->version = 4;
1115                 mnt->minorversion = 1;
1116                 break;
1117         default:
1118                 return 0;
1119         }
1120         return 1;
1121 }
1122
1123 static int nfs_get_option_str(substring_t args[], char **option)
1124 {
1125         kfree(*option);
1126         *option = match_strdup(args);
1127         return !option;
1128 }
1129
1130 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1131 {
1132         int rc;
1133         char *string;
1134
1135         string = match_strdup(args);
1136         if (string == NULL)
1137                 return -ENOMEM;
1138         rc = strict_strtoul(string, 10, option);
1139         kfree(string);
1140
1141         return rc;
1142 }
1143
1144 /*
1145  * Error-check and convert a string of mount options from user space into
1146  * a data structure.  The whole mount string is processed; bad options are
1147  * skipped as they are encountered.  If there were no errors, return 1;
1148  * otherwise return 0 (zero).
1149  */
1150 static int nfs_parse_mount_options(char *raw,
1151                                    struct nfs_parsed_mount_data *mnt)
1152 {
1153         char *p, *string, *secdata;
1154         int rc, sloppy = 0, invalid_option = 0;
1155         unsigned short protofamily = AF_UNSPEC;
1156         unsigned short mountfamily = AF_UNSPEC;
1157
1158         if (!raw) {
1159                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1160                 return 1;
1161         }
1162         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1163
1164         secdata = alloc_secdata();
1165         if (!secdata)
1166                 goto out_nomem;
1167
1168         rc = security_sb_copy_data(raw, secdata);
1169         if (rc)
1170                 goto out_security_failure;
1171
1172         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1173         if (rc)
1174                 goto out_security_failure;
1175
1176         free_secdata(secdata);
1177
1178         while ((p = strsep(&raw, ",")) != NULL) {
1179                 substring_t args[MAX_OPT_ARGS];
1180                 unsigned long option;
1181                 int token;
1182
1183                 if (!*p)
1184                         continue;
1185
1186                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1187
1188                 token = match_token(p, nfs_mount_option_tokens, args);
1189                 switch (token) {
1190
1191                 /*
1192                  * boolean options:  foo/nofoo
1193                  */
1194                 case Opt_soft:
1195                         mnt->flags |= NFS_MOUNT_SOFT;
1196                         break;
1197                 case Opt_hard:
1198                         mnt->flags &= ~NFS_MOUNT_SOFT;
1199                         break;
1200                 case Opt_posix:
1201                         mnt->flags |= NFS_MOUNT_POSIX;
1202                         break;
1203                 case Opt_noposix:
1204                         mnt->flags &= ~NFS_MOUNT_POSIX;
1205                         break;
1206                 case Opt_cto:
1207                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1208                         break;
1209                 case Opt_nocto:
1210                         mnt->flags |= NFS_MOUNT_NOCTO;
1211                         break;
1212                 case Opt_ac:
1213                         mnt->flags &= ~NFS_MOUNT_NOAC;
1214                         break;
1215                 case Opt_noac:
1216                         mnt->flags |= NFS_MOUNT_NOAC;
1217                         break;
1218                 case Opt_lock:
1219                         mnt->flags &= ~NFS_MOUNT_NONLM;
1220                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1221                                         NFS_MOUNT_LOCAL_FCNTL);
1222                         break;
1223                 case Opt_nolock:
1224                         mnt->flags |= NFS_MOUNT_NONLM;
1225                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1226                                        NFS_MOUNT_LOCAL_FCNTL);
1227                         break;
1228                 case Opt_udp:
1229                         mnt->flags &= ~NFS_MOUNT_TCP;
1230                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1231                         break;
1232                 case Opt_tcp:
1233                         mnt->flags |= NFS_MOUNT_TCP;
1234                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1235                         break;
1236                 case Opt_rdma:
1237                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1238                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1239                         xprt_load_transport(p);
1240                         break;
1241                 case Opt_acl:
1242                         mnt->flags &= ~NFS_MOUNT_NOACL;
1243                         break;
1244                 case Opt_noacl:
1245                         mnt->flags |= NFS_MOUNT_NOACL;
1246                         break;
1247                 case Opt_rdirplus:
1248                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1249                         break;
1250                 case Opt_nordirplus:
1251                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1252                         break;
1253                 case Opt_sharecache:
1254                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1255                         break;
1256                 case Opt_nosharecache:
1257                         mnt->flags |= NFS_MOUNT_UNSHARED;
1258                         break;
1259                 case Opt_resvport:
1260                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1261                         break;
1262                 case Opt_noresvport:
1263                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1264                         break;
1265                 case Opt_fscache:
1266                         mnt->options |= NFS_OPTION_FSCACHE;
1267                         kfree(mnt->fscache_uniq);
1268                         mnt->fscache_uniq = NULL;
1269                         break;
1270                 case Opt_nofscache:
1271                         mnt->options &= ~NFS_OPTION_FSCACHE;
1272                         kfree(mnt->fscache_uniq);
1273                         mnt->fscache_uniq = NULL;
1274                         break;
1275
1276                 /*
1277                  * options that take numeric values
1278                  */
1279                 case Opt_port:
1280                         if (nfs_get_option_ul(args, &option) ||
1281                             option > USHRT_MAX)
1282                                 goto out_invalid_value;
1283                         mnt->nfs_server.port = option;
1284                         break;
1285                 case Opt_rsize:
1286                         if (nfs_get_option_ul(args, &option))
1287                                 goto out_invalid_value;
1288                         mnt->rsize = option;
1289                         break;
1290                 case Opt_wsize:
1291                         if (nfs_get_option_ul(args, &option))
1292                                 goto out_invalid_value;
1293                         mnt->wsize = option;
1294                         break;
1295                 case Opt_bsize:
1296                         if (nfs_get_option_ul(args, &option))
1297                                 goto out_invalid_value;
1298                         mnt->bsize = option;
1299                         break;
1300                 case Opt_timeo:
1301                         if (nfs_get_option_ul(args, &option) || option == 0)
1302                                 goto out_invalid_value;
1303                         mnt->timeo = option;
1304                         break;
1305                 case Opt_retrans:
1306                         if (nfs_get_option_ul(args, &option) || option == 0)
1307                                 goto out_invalid_value;
1308                         mnt->retrans = option;
1309                         break;
1310                 case Opt_acregmin:
1311                         if (nfs_get_option_ul(args, &option))
1312                                 goto out_invalid_value;
1313                         mnt->acregmin = option;
1314                         break;
1315                 case Opt_acregmax:
1316                         if (nfs_get_option_ul(args, &option))
1317                                 goto out_invalid_value;
1318                         mnt->acregmax = option;
1319                         break;
1320                 case Opt_acdirmin:
1321                         if (nfs_get_option_ul(args, &option))
1322                                 goto out_invalid_value;
1323                         mnt->acdirmin = option;
1324                         break;
1325                 case Opt_acdirmax:
1326                         if (nfs_get_option_ul(args, &option))
1327                                 goto out_invalid_value;
1328                         mnt->acdirmax = option;
1329                         break;
1330                 case Opt_actimeo:
1331                         if (nfs_get_option_ul(args, &option))
1332                                 goto out_invalid_value;
1333                         mnt->acregmin = mnt->acregmax =
1334                         mnt->acdirmin = mnt->acdirmax = option;
1335                         break;
1336                 case Opt_namelen:
1337                         if (nfs_get_option_ul(args, &option))
1338                                 goto out_invalid_value;
1339                         mnt->namlen = option;
1340                         break;
1341                 case Opt_mountport:
1342                         if (nfs_get_option_ul(args, &option) ||
1343                             option > USHRT_MAX)
1344                                 goto out_invalid_value;
1345                         mnt->mount_server.port = option;
1346                         break;
1347                 case Opt_mountvers:
1348                         if (nfs_get_option_ul(args, &option) ||
1349                             option < NFS_MNT_VERSION ||
1350                             option > NFS_MNT3_VERSION)
1351                                 goto out_invalid_value;
1352                         mnt->mount_server.version = option;
1353                         break;
1354                 case Opt_minorversion:
1355                         if (nfs_get_option_ul(args, &option))
1356                                 goto out_invalid_value;
1357                         if (option > NFS4_MAX_MINOR_VERSION)
1358                                 goto out_invalid_value;
1359                         mnt->minorversion = option;
1360                         break;
1361
1362                 /*
1363                  * options that take text values
1364                  */
1365                 case Opt_nfsvers:
1366                         string = match_strdup(args);
1367                         if (string == NULL)
1368                                 goto out_nomem;
1369                         rc = nfs_parse_version_string(string, mnt, args);
1370                         kfree(string);
1371                         if (!rc)
1372                                 goto out_invalid_value;
1373                         break;
1374                 case Opt_sec:
1375                         string = match_strdup(args);
1376                         if (string == NULL)
1377                                 goto out_nomem;
1378                         rc = nfs_parse_security_flavors(string, mnt);
1379                         kfree(string);
1380                         if (!rc) {
1381                                 dfprintk(MOUNT, "NFS:   unrecognized "
1382                                                 "security flavor\n");
1383                                 return 0;
1384                         }
1385                         break;
1386                 case Opt_proto:
1387                         string = match_strdup(args);
1388                         if (string == NULL)
1389                                 goto out_nomem;
1390                         token = match_token(string,
1391                                             nfs_xprt_protocol_tokens, args);
1392
1393                         protofamily = AF_INET;
1394                         switch (token) {
1395                         case Opt_xprt_udp6:
1396                                 protofamily = AF_INET6;
1397                         case Opt_xprt_udp:
1398                                 mnt->flags &= ~NFS_MOUNT_TCP;
1399                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1400                                 break;
1401                         case Opt_xprt_tcp6:
1402                                 protofamily = AF_INET6;
1403                         case Opt_xprt_tcp:
1404                                 mnt->flags |= NFS_MOUNT_TCP;
1405                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1406                                 break;
1407                         case Opt_xprt_rdma:
1408                                 /* vector side protocols to TCP */
1409                                 mnt->flags |= NFS_MOUNT_TCP;
1410                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1411                                 xprt_load_transport(string);
1412                                 break;
1413                         default:
1414                                 dfprintk(MOUNT, "NFS:   unrecognized "
1415                                                 "transport protocol\n");
1416                                 kfree(string);
1417                                 return 0;
1418                         }
1419                         kfree(string);
1420                         break;
1421                 case Opt_mountproto:
1422                         string = match_strdup(args);
1423                         if (string == NULL)
1424                                 goto out_nomem;
1425                         token = match_token(string,
1426                                             nfs_xprt_protocol_tokens, args);
1427                         kfree(string);
1428
1429                         mountfamily = AF_INET;
1430                         switch (token) {
1431                         case Opt_xprt_udp6:
1432                                 mountfamily = AF_INET6;
1433                         case Opt_xprt_udp:
1434                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1435                                 break;
1436                         case Opt_xprt_tcp6:
1437                                 mountfamily = AF_INET6;
1438                         case Opt_xprt_tcp:
1439                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1440                                 break;
1441                         case Opt_xprt_rdma: /* not used for side protocols */
1442                         default:
1443                                 dfprintk(MOUNT, "NFS:   unrecognized "
1444                                                 "transport protocol\n");
1445                                 return 0;
1446                         }
1447                         break;
1448                 case Opt_addr:
1449                         string = match_strdup(args);
1450                         if (string == NULL)
1451                                 goto out_nomem;
1452                         mnt->nfs_server.addrlen =
1453                                 rpc_pton(mnt->net, string, strlen(string),
1454                                         (struct sockaddr *)
1455                                         &mnt->nfs_server.address,
1456                                         sizeof(mnt->nfs_server.address));
1457                         kfree(string);
1458                         if (mnt->nfs_server.addrlen == 0)
1459                                 goto out_invalid_address;
1460                         break;
1461                 case Opt_clientaddr:
1462                         if (nfs_get_option_str(args, &mnt->client_address))
1463                                 goto out_nomem;
1464                         break;
1465                 case Opt_mounthost:
1466                         if (nfs_get_option_str(args,
1467                                                &mnt->mount_server.hostname))
1468                                 goto out_nomem;
1469                         break;
1470                 case Opt_mountaddr:
1471                         string = match_strdup(args);
1472                         if (string == NULL)
1473                                 goto out_nomem;
1474                         mnt->mount_server.addrlen =
1475                                 rpc_pton(mnt->net, string, strlen(string),
1476                                         (struct sockaddr *)
1477                                         &mnt->mount_server.address,
1478                                         sizeof(mnt->mount_server.address));
1479                         kfree(string);
1480                         if (mnt->mount_server.addrlen == 0)
1481                                 goto out_invalid_address;
1482                         break;
1483                 case Opt_lookupcache:
1484                         string = match_strdup(args);
1485                         if (string == NULL)
1486                                 goto out_nomem;
1487                         token = match_token(string,
1488                                         nfs_lookupcache_tokens, args);
1489                         kfree(string);
1490                         switch (token) {
1491                                 case Opt_lookupcache_all:
1492                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1493                                         break;
1494                                 case Opt_lookupcache_positive:
1495                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1496                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1497                                         break;
1498                                 case Opt_lookupcache_none:
1499                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1500                                         break;
1501                                 default:
1502                                         dfprintk(MOUNT, "NFS:   invalid "
1503                                                         "lookupcache argument\n");
1504                                         return 0;
1505                         };
1506                         break;
1507                 case Opt_fscache_uniq:
1508                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1509                                 goto out_nomem;
1510                         mnt->options |= NFS_OPTION_FSCACHE;
1511                         break;
1512                 case Opt_local_lock:
1513                         string = match_strdup(args);
1514                         if (string == NULL)
1515                                 goto out_nomem;
1516                         token = match_token(string, nfs_local_lock_tokens,
1517                                         args);
1518                         kfree(string);
1519                         switch (token) {
1520                         case Opt_local_lock_all:
1521                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1522                                                NFS_MOUNT_LOCAL_FCNTL);
1523                                 break;
1524                         case Opt_local_lock_flock:
1525                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1526                                 break;
1527                         case Opt_local_lock_posix:
1528                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1529                                 break;
1530                         case Opt_local_lock_none:
1531                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1532                                                 NFS_MOUNT_LOCAL_FCNTL);
1533                                 break;
1534                         default:
1535                                 dfprintk(MOUNT, "NFS:   invalid "
1536                                                 "local_lock argument\n");
1537                                 return 0;
1538                         };
1539                         break;
1540
1541                 /*
1542                  * Special options
1543                  */
1544                 case Opt_sloppy:
1545                         sloppy = 1;
1546                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1547                         break;
1548                 case Opt_userspace:
1549                 case Opt_deprecated:
1550                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1551                                         "'%s'\n", p);
1552                         break;
1553
1554                 default:
1555                         invalid_option = 1;
1556                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1557                                         "'%s'\n", p);
1558                 }
1559         }
1560
1561         if (!sloppy && invalid_option)
1562                 return 0;
1563
1564         if (mnt->minorversion && mnt->version != 4)
1565                 goto out_minorversion_mismatch;
1566
1567         /*
1568          * verify that any proto=/mountproto= options match the address
1569          * familiies in the addr=/mountaddr= options.
1570          */
1571         if (protofamily != AF_UNSPEC &&
1572             protofamily != mnt->nfs_server.address.ss_family)
1573                 goto out_proto_mismatch;
1574
1575         if (mountfamily != AF_UNSPEC) {
1576                 if (mnt->mount_server.addrlen) {
1577                         if (mountfamily != mnt->mount_server.address.ss_family)
1578                                 goto out_mountproto_mismatch;
1579                 } else {
1580                         if (mountfamily != mnt->nfs_server.address.ss_family)
1581                                 goto out_mountproto_mismatch;
1582                 }
1583         }
1584
1585         return 1;
1586
1587 out_mountproto_mismatch:
1588         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1589                          "option\n");
1590         return 0;
1591 out_proto_mismatch:
1592         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1593         return 0;
1594 out_invalid_address:
1595         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1596         return 0;
1597 out_invalid_value:
1598         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1599         return 0;
1600 out_minorversion_mismatch:
1601         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1602                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1603         return 0;
1604 out_nomem:
1605         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1606         return 0;
1607 out_security_failure:
1608         free_secdata(secdata);
1609         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1610         return 0;
1611 }
1612
1613 /*
1614  * Match the requested auth flavors with the list returned by
1615  * the server.  Returns zero and sets the mount's authentication
1616  * flavor on success; returns -EACCES if server does not support
1617  * the requested flavor.
1618  */
1619 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1620                              struct nfs_mount_request *request)
1621 {
1622         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1623
1624         /*
1625          * Certain releases of Linux's mountd return an empty
1626          * flavor list.  To prevent behavioral regression with
1627          * these servers (ie. rejecting mounts that used to
1628          * succeed), revert to pre-2.6.32 behavior (no checking)
1629          * if the returned flavor list is empty.
1630          */
1631         if (server_authlist_len == 0)
1632                 return 0;
1633
1634         /*
1635          * We avoid sophisticated negotiating here, as there are
1636          * plenty of cases where we can get it wrong, providing
1637          * either too little or too much security.
1638          *
1639          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1640          * flavor listed first.  However, some servers list
1641          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1642          * preferred default, in args->auth_flavors[0] if user
1643          * didn't specify sec= mount option.
1644          */
1645         for (i = 0; i < args->auth_flavor_len; i++)
1646                 for (j = 0; j < server_authlist_len; j++)
1647                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1648                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1649                                         request->auth_flavs[j]);
1650                                 args->auth_flavors[0] = request->auth_flavs[j];
1651                                 return 0;
1652                         }
1653
1654         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1655         nfs_umount(request);
1656         return -EACCES;
1657 }
1658
1659 /*
1660  * Use the remote server's MOUNT service to request the NFS file handle
1661  * corresponding to the provided path.
1662  */
1663 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1664                          struct nfs_fh *root_fh)
1665 {
1666         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1667         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1668         struct nfs_mount_request request = {
1669                 .sap            = (struct sockaddr *)
1670                                                 &args->mount_server.address,
1671                 .dirpath        = args->nfs_server.export_path,
1672                 .protocol       = args->mount_server.protocol,
1673                 .fh             = root_fh,
1674                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1675                 .auth_flav_len  = &server_authlist_len,
1676                 .auth_flavs     = server_authlist,
1677                 .net            = args->net,
1678         };
1679         int status;
1680
1681         if (args->mount_server.version == 0) {
1682                 switch (args->version) {
1683                         default:
1684                                 args->mount_server.version = NFS_MNT3_VERSION;
1685                                 break;
1686                         case 2:
1687                                 args->mount_server.version = NFS_MNT_VERSION;
1688                 }
1689         }
1690         request.version = args->mount_server.version;
1691
1692         if (args->mount_server.hostname)
1693                 request.hostname = args->mount_server.hostname;
1694         else
1695                 request.hostname = args->nfs_server.hostname;
1696
1697         /*
1698          * Construct the mount server's address.
1699          */
1700         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1701                 memcpy(request.sap, &args->nfs_server.address,
1702                        args->nfs_server.addrlen);
1703                 args->mount_server.addrlen = args->nfs_server.addrlen;
1704         }
1705         request.salen = args->mount_server.addrlen;
1706         nfs_set_port(request.sap, &args->mount_server.port, 0);
1707
1708         /*
1709          * Now ask the mount server to map our export path
1710          * to a file handle.
1711          */
1712         status = nfs_mount(&request);
1713         if (status != 0) {
1714                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1715                                 request.hostname, status);
1716                 return status;
1717         }
1718
1719         /*
1720          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1721          */
1722         if (args->mount_server.version != NFS_MNT3_VERSION)
1723                 return 0;
1724         return nfs_walk_authlist(args, &request);
1725 }
1726
1727 /*
1728  * Split "dev_name" into "hostname:export_path".
1729  *
1730  * The leftmost colon demarks the split between the server's hostname
1731  * and the export path.  If the hostname starts with a left square
1732  * bracket, then it may contain colons.
1733  *
1734  * Note: caller frees hostname and export path, even on error.
1735  */
1736 static int nfs_parse_devname(const char *dev_name,
1737                              char **hostname, size_t maxnamlen,
1738                              char **export_path, size_t maxpathlen)
1739 {
1740         size_t len;
1741         char *end;
1742
1743         /* Is the host name protected with square brakcets? */
1744         if (*dev_name == '[') {
1745                 end = strchr(++dev_name, ']');
1746                 if (end == NULL || end[1] != ':')
1747                         goto out_bad_devname;
1748
1749                 len = end - dev_name;
1750                 end++;
1751         } else {
1752                 char *comma;
1753
1754                 end = strchr(dev_name, ':');
1755                 if (end == NULL)
1756                         goto out_bad_devname;
1757                 len = end - dev_name;
1758
1759                 /* kill possible hostname list: not supported */
1760                 comma = strchr(dev_name, ',');
1761                 if (comma != NULL && comma < end)
1762                         *comma = 0;
1763         }
1764
1765         if (len > maxnamlen)
1766                 goto out_hostname;
1767
1768         /* N.B. caller will free nfs_server.hostname in all cases */
1769         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1770         if (*hostname == NULL)
1771                 goto out_nomem;
1772         len = strlen(++end);
1773         if (len > maxpathlen)
1774                 goto out_path;
1775         *export_path = kstrndup(end, len, GFP_KERNEL);
1776         if (!*export_path)
1777                 goto out_nomem;
1778
1779         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1780         return 0;
1781
1782 out_bad_devname:
1783         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1784         return -EINVAL;
1785
1786 out_nomem:
1787         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1788         return -ENOMEM;
1789
1790 out_hostname:
1791         dfprintk(MOUNT, "NFS: server hostname too long\n");
1792         return -ENAMETOOLONG;
1793
1794 out_path:
1795         dfprintk(MOUNT, "NFS: export pathname too long\n");
1796         return -ENAMETOOLONG;
1797 }
1798
1799 /*
1800  * Validate the NFS2/NFS3 mount data
1801  * - fills in the mount root filehandle
1802  *
1803  * For option strings, user space handles the following behaviors:
1804  *
1805  * + DNS: mapping server host name to IP address ("addr=" option)
1806  *
1807  * + failure mode: how to behave if a mount request can't be handled
1808  *   immediately ("fg/bg" option)
1809  *
1810  * + retry: how often to retry a mount request ("retry=" option)
1811  *
1812  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1813  *   mountproto=tcp after mountproto=udp, and so on
1814  */
1815 static int nfs_validate_mount_data(void *options,
1816                                    struct nfs_parsed_mount_data *args,
1817                                    struct nfs_fh *mntfh,
1818                                    const char *dev_name)
1819 {
1820         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1821         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1822
1823         if (data == NULL)
1824                 goto out_no_data;
1825
1826         switch (data->version) {
1827         case 1:
1828                 data->namlen = 0;
1829         case 2:
1830                 data->bsize = 0;
1831         case 3:
1832                 if (data->flags & NFS_MOUNT_VER3)
1833                         goto out_no_v3;
1834                 data->root.size = NFS2_FHSIZE;
1835                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1836         case 4:
1837                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1838                         goto out_no_sec;
1839         case 5:
1840                 memset(data->context, 0, sizeof(data->context));
1841         case 6:
1842                 if (data->flags & NFS_MOUNT_VER3) {
1843                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1844                                 goto out_invalid_fh;
1845                         mntfh->size = data->root.size;
1846                         args->version = 3;
1847                 } else {
1848                         mntfh->size = NFS2_FHSIZE;
1849                         args->version = 2;
1850                 }
1851
1852
1853                 memcpy(mntfh->data, data->root.data, mntfh->size);
1854                 if (mntfh->size < sizeof(mntfh->data))
1855                         memset(mntfh->data + mntfh->size, 0,
1856                                sizeof(mntfh->data) - mntfh->size);
1857
1858                 /*
1859                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1860                  * can deal with.
1861                  */
1862                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1863                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1864                 args->rsize             = data->rsize;
1865                 args->wsize             = data->wsize;
1866                 args->timeo             = data->timeo;
1867                 args->retrans           = data->retrans;
1868                 args->acregmin          = data->acregmin;
1869                 args->acregmax          = data->acregmax;
1870                 args->acdirmin          = data->acdirmin;
1871                 args->acdirmax          = data->acdirmax;
1872
1873                 memcpy(sap, &data->addr, sizeof(data->addr));
1874                 args->nfs_server.addrlen = sizeof(data->addr);
1875                 if (!nfs_verify_server_address(sap))
1876                         goto out_no_address;
1877
1878                 if (!(data->flags & NFS_MOUNT_TCP))
1879                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1880                 /* N.B. caller will free nfs_server.hostname in all cases */
1881                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1882                 args->namlen            = data->namlen;
1883                 args->bsize             = data->bsize;
1884
1885                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1886                         args->auth_flavors[0] = data->pseudoflavor;
1887                 if (!args->nfs_server.hostname)
1888                         goto out_nomem;
1889
1890                 if (!(data->flags & NFS_MOUNT_NONLM))
1891                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1892                                          NFS_MOUNT_LOCAL_FCNTL);
1893                 else
1894                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1895                                         NFS_MOUNT_LOCAL_FCNTL);
1896                 /*
1897                  * The legacy version 6 binary mount data from userspace has a
1898                  * field used only to transport selinux information into the
1899                  * the kernel.  To continue to support that functionality we
1900                  * have a touch of selinux knowledge here in the NFS code. The
1901                  * userspace code converted context=blah to just blah so we are
1902                  * converting back to the full string selinux understands.
1903                  */
1904                 if (data->context[0]){
1905 #ifdef CONFIG_SECURITY_SELINUX
1906                         int rc;
1907                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1908                         if (!opts_str)
1909                                 return -ENOMEM;
1910                         strcpy(opts_str, "context=");
1911                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1912                         strcat(opts_str, &data->context[0]);
1913                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1914                         kfree(opts_str);
1915                         if (rc)
1916                                 return rc;
1917 #else
1918                         return -EINVAL;
1919 #endif
1920                 }
1921
1922                 break;
1923         default: {
1924                 int status;
1925
1926                 if (nfs_parse_mount_options((char *)options, args) == 0)
1927                         return -EINVAL;
1928
1929                 if (!nfs_verify_server_address(sap))
1930                         goto out_no_address;
1931
1932                 if (args->version == 4)
1933 #ifdef CONFIG_NFS_V4
1934                         return nfs4_validate_text_mount_data(options,
1935                                                              args, dev_name);
1936 #else
1937                         goto out_v4_not_compiled;
1938 #endif
1939
1940                 nfs_set_port(sap, &args->nfs_server.port, 0);
1941
1942                 nfs_set_mount_transport_protocol(args);
1943
1944                 status = nfs_parse_devname(dev_name,
1945                                            &args->nfs_server.hostname,
1946                                            PAGE_SIZE,
1947                                            &args->nfs_server.export_path,
1948                                            NFS_MAXPATHLEN);
1949                 if (!status)
1950                         status = nfs_try_mount(args, mntfh);
1951
1952                 kfree(args->nfs_server.export_path);
1953                 args->nfs_server.export_path = NULL;
1954
1955                 if (status)
1956                         return status;
1957
1958                 break;
1959                 }
1960         }
1961
1962 #ifndef CONFIG_NFS_V3
1963         if (args->version == 3)
1964                 goto out_v3_not_compiled;
1965 #endif /* !CONFIG_NFS_V3 */
1966
1967         return 0;
1968
1969 out_no_data:
1970         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1971         return -EINVAL;
1972
1973 out_no_v3:
1974         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1975                  data->version);
1976         return -EINVAL;
1977
1978 out_no_sec:
1979         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1980         return -EINVAL;
1981
1982 #ifndef CONFIG_NFS_V3
1983 out_v3_not_compiled:
1984         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1985         return -EPROTONOSUPPORT;
1986 #endif /* !CONFIG_NFS_V3 */
1987
1988 #ifndef CONFIG_NFS_V4
1989 out_v4_not_compiled:
1990         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1991         return -EPROTONOSUPPORT;
1992 #endif /* !CONFIG_NFS_V4 */
1993
1994 out_nomem:
1995         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1996         return -ENOMEM;
1997
1998 out_no_address:
1999         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2000         return -EINVAL;
2001
2002 out_invalid_fh:
2003         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2004         return -EINVAL;
2005 }
2006
2007 static int
2008 nfs_compare_remount_data(struct nfs_server *nfss,
2009                          struct nfs_parsed_mount_data *data)
2010 {
2011         if (data->flags != nfss->flags ||
2012             data->rsize != nfss->rsize ||
2013             data->wsize != nfss->wsize ||
2014             data->retrans != nfss->client->cl_timeout->to_retries ||
2015             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2016             data->acregmin != nfss->acregmin / HZ ||
2017             data->acregmax != nfss->acregmax / HZ ||
2018             data->acdirmin != nfss->acdirmin / HZ ||
2019             data->acdirmax != nfss->acdirmax / HZ ||
2020             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2021             data->nfs_server.port != nfss->port ||
2022             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2023             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2024                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2025                 return -EINVAL;
2026
2027         return 0;
2028 }
2029
2030 static int
2031 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2032 {
2033         int error;
2034         struct nfs_server *nfss = sb->s_fs_info;
2035         struct nfs_parsed_mount_data *data;
2036         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2037         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2038         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2039
2040         /*
2041          * Userspace mount programs that send binary options generally send
2042          * them populated with default values. We have no way to know which
2043          * ones were explicitly specified. Fall back to legacy behavior and
2044          * just return success.
2045          */
2046         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2047             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2048                                            options->version <= 6))))
2049                 return 0;
2050
2051         data = kzalloc(sizeof(*data), GFP_KERNEL);
2052         if (data == NULL)
2053                 return -ENOMEM;
2054
2055         /* fill out struct with values from existing mount */
2056         data->flags = nfss->flags;
2057         data->rsize = nfss->rsize;
2058         data->wsize = nfss->wsize;
2059         data->retrans = nfss->client->cl_timeout->to_retries;
2060         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2061         data->acregmin = nfss->acregmin / HZ;
2062         data->acregmax = nfss->acregmax / HZ;
2063         data->acdirmin = nfss->acdirmin / HZ;
2064         data->acdirmax = nfss->acdirmax / HZ;
2065         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2066         data->nfs_server.port = nfss->port;
2067         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2068         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2069                 data->nfs_server.addrlen);
2070
2071         /* overwrite those values with any that were specified */
2072         error = nfs_parse_mount_options((char *)options, data);
2073         if (error < 0)
2074                 goto out;
2075
2076         /*
2077          * noac is a special case. It implies -o sync, but that's not
2078          * necessarily reflected in the mtab options. do_remount_sb
2079          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2080          * remount options, so we have to explicitly reset it.
2081          */
2082         if (data->flags & NFS_MOUNT_NOAC)
2083                 *flags |= MS_SYNCHRONOUS;
2084
2085         /* compare new mount options with old ones */
2086         error = nfs_compare_remount_data(nfss, data);
2087 out:
2088         kfree(data);
2089         return error;
2090 }
2091
2092 /*
2093  * Initialise the common bits of the superblock
2094  */
2095 static inline void nfs_initialise_sb(struct super_block *sb)
2096 {
2097         struct nfs_server *server = NFS_SB(sb);
2098
2099         sb->s_magic = NFS_SUPER_MAGIC;
2100
2101         /* We probably want something more informative here */
2102         snprintf(sb->s_id, sizeof(sb->s_id),
2103                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2104
2105         if (sb->s_blocksize == 0)
2106                 sb->s_blocksize = nfs_block_bits(server->wsize,
2107                                                  &sb->s_blocksize_bits);
2108
2109         sb->s_bdi = &server->backing_dev_info;
2110
2111         nfs_super_set_maxbytes(sb, server->maxfilesize);
2112 }
2113
2114 /*
2115  * Finish setting up an NFS2/3 superblock
2116  */
2117 static void nfs_fill_super(struct super_block *sb,
2118                            struct nfs_parsed_mount_data *data)
2119 {
2120         struct nfs_server *server = NFS_SB(sb);
2121
2122         sb->s_blocksize_bits = 0;
2123         sb->s_blocksize = 0;
2124         if (data->bsize)
2125                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2126
2127         if (server->nfs_client->rpc_ops->version == 3) {
2128                 /* The VFS shouldn't apply the umask to mode bits. We will do
2129                  * so ourselves when necessary.
2130                  */
2131                 sb->s_flags |= MS_POSIXACL;
2132                 sb->s_time_gran = 1;
2133         }
2134
2135         sb->s_op = &nfs_sops;
2136         nfs_initialise_sb(sb);
2137 }
2138
2139 /*
2140  * Finish setting up a cloned NFS2/3 superblock
2141  */
2142 static void nfs_clone_super(struct super_block *sb,
2143                             const struct super_block *old_sb)
2144 {
2145         struct nfs_server *server = NFS_SB(sb);
2146
2147         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2148         sb->s_blocksize = old_sb->s_blocksize;
2149         sb->s_maxbytes = old_sb->s_maxbytes;
2150
2151         if (server->nfs_client->rpc_ops->version == 3) {
2152                 /* The VFS shouldn't apply the umask to mode bits. We will do
2153                  * so ourselves when necessary.
2154                  */
2155                 sb->s_flags |= MS_POSIXACL;
2156                 sb->s_time_gran = 1;
2157         }
2158
2159         sb->s_op = old_sb->s_op;
2160         nfs_initialise_sb(sb);
2161 }
2162
2163 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2164 {
2165         const struct nfs_server *a = s->s_fs_info;
2166         const struct rpc_clnt *clnt_a = a->client;
2167         const struct rpc_clnt *clnt_b = b->client;
2168
2169         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2170                 goto Ebusy;
2171         if (a->nfs_client != b->nfs_client)
2172                 goto Ebusy;
2173         if (a->flags != b->flags)
2174                 goto Ebusy;
2175         if (a->wsize != b->wsize)
2176                 goto Ebusy;
2177         if (a->rsize != b->rsize)
2178                 goto Ebusy;
2179         if (a->acregmin != b->acregmin)
2180                 goto Ebusy;
2181         if (a->acregmax != b->acregmax)
2182                 goto Ebusy;
2183         if (a->acdirmin != b->acdirmin)
2184                 goto Ebusy;
2185         if (a->acdirmax != b->acdirmax)
2186                 goto Ebusy;
2187         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2188                 goto Ebusy;
2189         return 1;
2190 Ebusy:
2191         return 0;
2192 }
2193
2194 struct nfs_sb_mountdata {
2195         struct nfs_server *server;
2196         int mntflags;
2197 };
2198
2199 static int nfs_set_super(struct super_block *s, void *data)
2200 {
2201         struct nfs_sb_mountdata *sb_mntdata = data;
2202         struct nfs_server *server = sb_mntdata->server;
2203         int ret;
2204
2205         s->s_flags = sb_mntdata->mntflags;
2206         s->s_fs_info = server;
2207         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2208         ret = set_anon_super(s, server);
2209         if (ret == 0)
2210                 server->s_dev = s->s_dev;
2211         return ret;
2212 }
2213
2214 static int nfs_compare_super_address(struct nfs_server *server1,
2215                                      struct nfs_server *server2)
2216 {
2217         struct sockaddr *sap1, *sap2;
2218
2219         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2220         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2221
2222         if (sap1->sa_family != sap2->sa_family)
2223                 return 0;
2224
2225         switch (sap1->sa_family) {
2226         case AF_INET: {
2227                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2228                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2229                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2230                         return 0;
2231                 if (sin1->sin_port != sin2->sin_port)
2232                         return 0;
2233                 break;
2234         }
2235         case AF_INET6: {
2236                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2237                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2238                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2239                         return 0;
2240                 if (sin1->sin6_port != sin2->sin6_port)
2241                         return 0;
2242                 break;
2243         }
2244         default:
2245                 return 0;
2246         }
2247
2248         return 1;
2249 }
2250
2251 static int nfs_compare_super(struct super_block *sb, void *data)
2252 {
2253         struct nfs_sb_mountdata *sb_mntdata = data;
2254         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2255         int mntflags = sb_mntdata->mntflags;
2256
2257         if (!nfs_compare_super_address(old, server))
2258                 return 0;
2259         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2260         if (old->flags & NFS_MOUNT_UNSHARED)
2261                 return 0;
2262         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2263                 return 0;
2264         return nfs_compare_mount_options(sb, server, mntflags);
2265 }
2266
2267 static int nfs_bdi_register(struct nfs_server *server)
2268 {
2269         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2270 }
2271
2272 static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2273         int flags, const char *dev_name, void *raw_data)
2274 {
2275         struct nfs_server *server = NULL;
2276         struct super_block *s;
2277         struct nfs_parsed_mount_data *data;
2278         struct nfs_fh *mntfh;
2279         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2280         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2281         struct nfs_sb_mountdata sb_mntdata = {
2282                 .mntflags = flags,
2283         };
2284         int error;
2285
2286         data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
2287         mntfh = nfs_alloc_fhandle();
2288         if (data == NULL || mntfh == NULL)
2289                 goto out;
2290
2291         /* Validate the mount data */
2292         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2293         if (error < 0) {
2294                 mntroot = ERR_PTR(error);
2295                 goto out;
2296         }
2297
2298 #ifdef CONFIG_NFS_V4
2299         if (data->version == 4) {
2300                 mntroot = nfs4_try_mount(flags, dev_name, data);
2301                 goto out;
2302         }
2303 #endif  /* CONFIG_NFS_V4 */
2304
2305         /* Get a volume representation */
2306         server = nfs_create_server(data, mntfh);
2307         if (IS_ERR(server)) {
2308                 mntroot = ERR_CAST(server);
2309                 goto out;
2310         }
2311         sb_mntdata.server = server;
2312
2313         if (server->flags & NFS_MOUNT_UNSHARED)
2314                 compare_super = NULL;
2315
2316         /* -o noac implies -o sync */
2317         if (server->flags & NFS_MOUNT_NOAC)
2318                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2319
2320         /* Get a superblock - note that we may end up sharing one that already exists */
2321         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2322         if (IS_ERR(s)) {
2323                 mntroot = ERR_CAST(s);
2324                 goto out_err_nosb;
2325         }
2326
2327         if (s->s_fs_info != server) {
2328                 nfs_free_server(server);
2329                 server = NULL;
2330         } else {
2331                 error = nfs_bdi_register(server);
2332                 if (error) {
2333                         mntroot = ERR_PTR(error);
2334                         goto error_splat_bdi;
2335                 }
2336         }
2337
2338         if (!s->s_root) {
2339                 /* initial superblock/root creation */
2340                 nfs_fill_super(s, data);
2341                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2342         }
2343
2344         mntroot = nfs_get_root(s, mntfh, dev_name);
2345         if (IS_ERR(mntroot))
2346                 goto error_splat_super;
2347
2348         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2349         if (error)
2350                 goto error_splat_root;
2351
2352         s->s_flags |= MS_ACTIVE;
2353
2354 out:
2355         nfs_free_parsed_mount_data(data);
2356         nfs_free_fhandle(mntfh);
2357         return mntroot;
2358
2359 out_err_nosb:
2360         nfs_free_server(server);
2361         goto out;
2362
2363 error_splat_root:
2364         dput(mntroot);
2365         mntroot = ERR_PTR(error);
2366 error_splat_super:
2367         if (server && !s->s_root)
2368                 bdi_unregister(&server->backing_dev_info);
2369 error_splat_bdi:
2370         deactivate_locked_super(s);
2371         goto out;
2372 }
2373
2374 /*
2375  * Ensure that we unregister the bdi before kill_anon_super
2376  * releases the device name
2377  */
2378 static void nfs_put_super(struct super_block *s)
2379 {
2380         struct nfs_server *server = NFS_SB(s);
2381
2382         bdi_unregister(&server->backing_dev_info);
2383 }
2384
2385 /*
2386  * Destroy an NFS2/3 superblock
2387  */
2388 static void nfs_kill_super(struct super_block *s)
2389 {
2390         struct nfs_server *server = NFS_SB(s);
2391
2392         kill_anon_super(s);
2393         nfs_fscache_release_super_cookie(s);
2394         nfs_free_server(server);
2395 }
2396
2397 /*
2398  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2399  */
2400 static struct dentry *
2401 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2402                 const char *dev_name, void *raw_data)
2403 {
2404         struct nfs_clone_mount *data = raw_data;
2405         struct super_block *s;
2406         struct nfs_server *server;
2407         struct dentry *mntroot;
2408         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2409         struct nfs_sb_mountdata sb_mntdata = {
2410                 .mntflags = flags,
2411         };
2412         int error;
2413
2414         dprintk("--> nfs_xdev_mount()\n");
2415
2416         /* create a new volume representation */
2417         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2418         if (IS_ERR(server)) {
2419                 error = PTR_ERR(server);
2420                 goto out_err_noserver;
2421         }
2422         sb_mntdata.server = server;
2423
2424         if (server->flags & NFS_MOUNT_UNSHARED)
2425                 compare_super = NULL;
2426
2427         /* -o noac implies -o sync */
2428         if (server->flags & NFS_MOUNT_NOAC)
2429                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2430
2431         /* Get a superblock - note that we may end up sharing one that already exists */
2432         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2433         if (IS_ERR(s)) {
2434                 error = PTR_ERR(s);
2435                 goto out_err_nosb;
2436         }
2437
2438         if (s->s_fs_info != server) {
2439                 nfs_free_server(server);
2440                 server = NULL;
2441         } else {
2442                 error = nfs_bdi_register(server);
2443                 if (error)
2444                         goto error_splat_bdi;
2445         }
2446
2447         if (!s->s_root) {
2448                 /* initial superblock/root creation */
2449                 nfs_clone_super(s, data->sb);
2450                 nfs_fscache_get_super_cookie(s, NULL, data);
2451         }
2452
2453         mntroot = nfs_get_root(s, data->fh, dev_name);
2454         if (IS_ERR(mntroot)) {
2455                 error = PTR_ERR(mntroot);
2456                 goto error_splat_super;
2457         }
2458         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2459                 dput(mntroot);
2460                 error = -ESTALE;
2461                 goto error_splat_super;
2462         }
2463
2464         s->s_flags |= MS_ACTIVE;
2465
2466         /* clone any lsm security options from the parent to the new sb */
2467         security_sb_clone_mnt_opts(data->sb, s);
2468
2469         dprintk("<-- nfs_xdev_mount() = 0\n");
2470         return mntroot;
2471
2472 out_err_nosb:
2473         nfs_free_server(server);
2474 out_err_noserver:
2475         dprintk("<-- nfs_xdev_mount() = %d [error]\n", error);
2476         return ERR_PTR(error);
2477
2478 error_splat_super:
2479         if (server && !s->s_root)
2480                 bdi_unregister(&server->backing_dev_info);
2481 error_splat_bdi:
2482         deactivate_locked_super(s);
2483         dprintk("<-- nfs_xdev_mount() = %d [splat]\n", error);
2484         return ERR_PTR(error);
2485 }
2486
2487 #ifdef CONFIG_NFS_V4
2488
2489 /*
2490  * Finish setting up a cloned NFS4 superblock
2491  */
2492 static void nfs4_clone_super(struct super_block *sb,
2493                             const struct super_block *old_sb)
2494 {
2495         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2496         sb->s_blocksize = old_sb->s_blocksize;
2497         sb->s_maxbytes = old_sb->s_maxbytes;
2498         sb->s_time_gran = 1;
2499         sb->s_op = old_sb->s_op;
2500         /*
2501          * The VFS shouldn't apply the umask to mode bits. We will do
2502          * so ourselves when necessary.
2503          */
2504         sb->s_flags  |= MS_POSIXACL;
2505         sb->s_xattr  = old_sb->s_xattr;
2506         nfs_initialise_sb(sb);
2507 }
2508
2509 /*
2510  * Set up an NFS4 superblock
2511  */
2512 static void nfs4_fill_super(struct super_block *sb)
2513 {
2514         sb->s_time_gran = 1;
2515         sb->s_op = &nfs4_sops;
2516         /*
2517          * The VFS shouldn't apply the umask to mode bits. We will do
2518          * so ourselves when necessary.
2519          */
2520         sb->s_flags  |= MS_POSIXACL;
2521         sb->s_xattr = nfs4_xattr_handlers;
2522         nfs_initialise_sb(sb);
2523 }
2524
2525 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2526 {
2527         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2528                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2529 }
2530
2531 static int nfs4_validate_text_mount_data(void *options,
2532                                          struct nfs_parsed_mount_data *args,
2533                                          const char *dev_name)
2534 {
2535         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2536
2537         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2538
2539         nfs_validate_transport_protocol(args);
2540
2541         nfs4_validate_mount_flags(args);
2542
2543         if (args->version != 4) {
2544                 dfprintk(MOUNT,
2545                          "NFS4: Illegal mount version\n");
2546                 return -EINVAL;
2547         }
2548
2549         if (args->auth_flavor_len > 1) {
2550                 dfprintk(MOUNT,
2551                          "NFS4: Too many RPC auth flavours specified\n");
2552                 return -EINVAL;
2553         }
2554
2555         if (args->client_address == NULL) {
2556                 dfprintk(MOUNT,
2557                          "NFS4: mount program didn't pass callback address\n");
2558                 return -EINVAL;
2559         }
2560
2561         return nfs_parse_devname(dev_name,
2562                                    &args->nfs_server.hostname,
2563                                    NFS4_MAXNAMLEN,
2564                                    &args->nfs_server.export_path,
2565                                    NFS4_MAXPATHLEN);
2566 }
2567
2568 /*
2569  * Validate NFSv4 mount options
2570  */
2571 static int nfs4_validate_mount_data(void *options,
2572                                     struct nfs_parsed_mount_data *args,
2573                                     const char *dev_name)
2574 {
2575         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2576         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2577         char *c;
2578
2579         if (data == NULL)
2580                 goto out_no_data;
2581
2582         switch (data->version) {
2583         case 1:
2584                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2585                         goto out_no_address;
2586                 if (data->host_addrlen == 0)
2587                         goto out_no_address;
2588                 args->nfs_server.addrlen = data->host_addrlen;
2589                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2590                         return -EFAULT;
2591                 if (!nfs_verify_server_address(sap))
2592                         goto out_no_address;
2593
2594                 if (data->auth_flavourlen) {
2595                         if (data->auth_flavourlen > 1)
2596                                 goto out_inval_auth;
2597                         if (copy_from_user(&args->auth_flavors[0],
2598                                            data->auth_flavours,
2599                                            sizeof(args->auth_flavors[0])))
2600                                 return -EFAULT;
2601                 }
2602
2603                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2604                 if (IS_ERR(c))
2605                         return PTR_ERR(c);
2606                 args->nfs_server.hostname = c;
2607
2608                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2609                 if (IS_ERR(c))
2610                         return PTR_ERR(c);
2611                 args->nfs_server.export_path = c;
2612                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2613
2614                 c = strndup_user(data->client_addr.data, 16);
2615                 if (IS_ERR(c))
2616                         return PTR_ERR(c);
2617                 args->client_address = c;
2618
2619                 /*
2620                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2621                  * can deal with.
2622                  */
2623
2624                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2625                 args->rsize     = data->rsize;
2626                 args->wsize     = data->wsize;
2627                 args->timeo     = data->timeo;
2628                 args->retrans   = data->retrans;
2629                 args->acregmin  = data->acregmin;
2630                 args->acregmax  = data->acregmax;
2631                 args->acdirmin  = data->acdirmin;
2632                 args->acdirmax  = data->acdirmax;
2633                 args->nfs_server.protocol = data->proto;
2634                 nfs_validate_transport_protocol(args);
2635
2636                 break;
2637         default:
2638                 if (nfs_parse_mount_options((char *)options, args) == 0)
2639                         return -EINVAL;
2640
2641                 if (!nfs_verify_server_address(sap))
2642                         return -EINVAL;
2643
2644                 return nfs4_validate_text_mount_data(options, args, dev_name);
2645         }
2646
2647         return 0;
2648
2649 out_no_data:
2650         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2651         return -EINVAL;
2652
2653 out_inval_auth:
2654         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2655                  data->auth_flavourlen);
2656         return -EINVAL;
2657
2658 out_no_address:
2659         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2660         return -EINVAL;
2661 }
2662
2663 /*
2664  * Get the superblock for the NFS4 root partition
2665  */
2666 static struct dentry *
2667 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
2668                   const char *dev_name, void *raw_data)
2669 {
2670         struct nfs_parsed_mount_data *data = raw_data;
2671         struct super_block *s;
2672         struct nfs_server *server;
2673         struct nfs_fh *mntfh;
2674         struct dentry *mntroot;
2675         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2676         struct nfs_sb_mountdata sb_mntdata = {
2677                 .mntflags = flags,
2678         };
2679         int error = -ENOMEM;
2680
2681         mntfh = nfs_alloc_fhandle();
2682         if (data == NULL || mntfh == NULL)
2683                 goto out;
2684
2685         /* Get a volume representation */
2686         server = nfs4_create_server(data, mntfh);
2687         if (IS_ERR(server)) {
2688                 error = PTR_ERR(server);
2689                 goto out;
2690         }
2691         sb_mntdata.server = server;
2692
2693         if (server->flags & NFS4_MOUNT_UNSHARED)
2694                 compare_super = NULL;
2695
2696         /* -o noac implies -o sync */
2697         if (server->flags & NFS_MOUNT_NOAC)
2698                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2699
2700         /* Get a superblock - note that we may end up sharing one that already exists */
2701         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2702         if (IS_ERR(s)) {
2703                 error = PTR_ERR(s);
2704                 goto out_free;
2705         }
2706
2707         if (s->s_fs_info != server) {
2708                 nfs_free_server(server);
2709                 server = NULL;
2710         } else {
2711                 error = nfs_bdi_register(server);
2712                 if (error)
2713                         goto error_splat_bdi;
2714         }
2715
2716         if (!s->s_root) {
2717                 /* initial superblock/root creation */
2718                 nfs4_fill_super(s);
2719                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2720         }
2721
2722         mntroot = nfs4_get_root(s, mntfh, dev_name);
2723         if (IS_ERR(mntroot)) {
2724                 error = PTR_ERR(mntroot);
2725                 goto error_splat_super;
2726         }
2727
2728         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2729         if (error)
2730                 goto error_splat_root;
2731
2732         s->s_flags |= MS_ACTIVE;
2733
2734         nfs_free_fhandle(mntfh);
2735         return mntroot;
2736
2737 out:
2738         nfs_free_fhandle(mntfh);
2739         return ERR_PTR(error);
2740
2741 out_free:
2742         nfs_free_server(server);
2743         goto out;
2744
2745 error_splat_root:
2746         dput(mntroot);
2747 error_splat_super:
2748         if (server && !s->s_root)
2749                 bdi_unregister(&server->backing_dev_info);
2750 error_splat_bdi:
2751         deactivate_locked_super(s);
2752         goto out;
2753 }
2754
2755 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2756                 int flags, void *data, const char *hostname)
2757 {
2758         struct vfsmount *root_mnt;
2759         char *root_devname;
2760         size_t len;
2761
2762         len = strlen(hostname) + 3;
2763         root_devname = kmalloc(len, GFP_KERNEL);
2764         if (root_devname == NULL)
2765                 return ERR_PTR(-ENOMEM);
2766         snprintf(root_devname, len, "%s:/", hostname);
2767         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2768         kfree(root_devname);
2769         return root_mnt;
2770 }
2771
2772 struct nfs_referral_count {
2773         struct list_head list;
2774         const struct task_struct *task;
2775         unsigned int referral_count;
2776 };
2777
2778 static LIST_HEAD(nfs_referral_count_list);
2779 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2780
2781 static struct nfs_referral_count *nfs_find_referral_count(void)
2782 {
2783         struct nfs_referral_count *p;
2784
2785         list_for_each_entry(p, &nfs_referral_count_list, list) {
2786                 if (p->task == current)
2787                         return p;
2788         }
2789         return NULL;
2790 }
2791
2792 #define NFS_MAX_NESTED_REFERRALS 2
2793
2794 static int nfs_referral_loop_protect(void)
2795 {
2796         struct nfs_referral_count *p, *new;
2797         int ret = -ENOMEM;
2798
2799         new = kmalloc(sizeof(*new), GFP_KERNEL);
2800         if (!new)
2801                 goto out;
2802         new->task = current;
2803         new->referral_count = 1;
2804
2805         ret = 0;
2806         spin_lock(&nfs_referral_count_list_lock);
2807         p = nfs_find_referral_count();
2808         if (p != NULL) {
2809                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2810                         ret = -ELOOP;
2811                 else
2812                         p->referral_count++;
2813         } else {
2814                 list_add(&new->list, &nfs_referral_count_list);
2815                 new = NULL;
2816         }
2817         spin_unlock(&nfs_referral_count_list_lock);
2818         kfree(new);
2819 out:
2820         return ret;
2821 }
2822
2823 static void nfs_referral_loop_unprotect(void)
2824 {
2825         struct nfs_referral_count *p;
2826
2827         spin_lock(&nfs_referral_count_list_lock);
2828         p = nfs_find_referral_count();
2829         p->referral_count--;
2830         if (p->referral_count == 0)
2831                 list_del(&p->list);
2832         else
2833                 p = NULL;
2834         spin_unlock(&nfs_referral_count_list_lock);
2835         kfree(p);
2836 }
2837
2838 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
2839                 const char *export_path)
2840 {
2841         struct dentry *dentry;
2842         int err;
2843
2844         if (IS_ERR(root_mnt))
2845                 return ERR_CAST(root_mnt);
2846
2847         err = nfs_referral_loop_protect();
2848         if (err) {
2849                 mntput(root_mnt);
2850                 return ERR_PTR(err);
2851         }
2852
2853         dentry = mount_subtree(root_mnt, export_path);
2854         nfs_referral_loop_unprotect();
2855
2856         return dentry;
2857 }
2858
2859 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
2860                          struct nfs_parsed_mount_data *data)
2861 {
2862         char *export_path;
2863         struct vfsmount *root_mnt;
2864         struct dentry *res;
2865
2866         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2867
2868         export_path = data->nfs_server.export_path;
2869         data->nfs_server.export_path = "/";
2870         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2871                         data->nfs_server.hostname);
2872         data->nfs_server.export_path = export_path;
2873
2874         res = nfs_follow_remote_path(root_mnt, export_path);
2875
2876         dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
2877                         IS_ERR(res) ? PTR_ERR(res) : 0,
2878                         IS_ERR(res) ? " [error]" : "");
2879         return res;
2880 }
2881
2882 /*
2883  * Get the superblock for an NFS4 mountpoint
2884  */
2885 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
2886         int flags, const char *dev_name, void *raw_data)
2887 {
2888         struct nfs_parsed_mount_data *data;
2889         int error = -ENOMEM;
2890         struct dentry *res = ERR_PTR(-ENOMEM);
2891
2892         data = nfs_alloc_parsed_mount_data(4);
2893         if (data == NULL)
2894                 goto out;
2895
2896         /* Validate the mount data */
2897         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2898         if (error < 0) {
2899                 res = ERR_PTR(error);
2900                 goto out;
2901         }
2902
2903         res = nfs4_try_mount(flags, dev_name, data);
2904         if (IS_ERR(res))
2905                 error = PTR_ERR(res);
2906
2907 out:
2908         nfs_free_parsed_mount_data(data);
2909         dprintk("<-- nfs4_mount() = %d%s\n", error,
2910                         error != 0 ? " [error]" : "");
2911         return res;
2912 }
2913
2914 static void nfs4_kill_super(struct super_block *sb)
2915 {
2916         struct nfs_server *server = NFS_SB(sb);
2917
2918         dprintk("--> %s\n", __func__);
2919         nfs_super_return_all_delegations(sb);
2920         kill_anon_super(sb);
2921         nfs_fscache_release_super_cookie(sb);
2922         nfs_free_server(server);
2923         dprintk("<-- %s\n", __func__);
2924 }
2925
2926 /*
2927  * Clone an NFS4 server record on xdev traversal (FSID-change)
2928  */
2929 static struct dentry *
2930 nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
2931                  const char *dev_name, void *raw_data)
2932 {
2933         struct nfs_clone_mount *data = raw_data;
2934         struct super_block *s;
2935         struct nfs_server *server;
2936         struct dentry *mntroot;
2937         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2938         struct nfs_sb_mountdata sb_mntdata = {
2939                 .mntflags = flags,
2940         };
2941         int error;
2942
2943         dprintk("--> nfs4_xdev_mount()\n");
2944
2945         /* create a new volume representation */
2946         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2947         if (IS_ERR(server)) {
2948                 error = PTR_ERR(server);
2949                 goto out_err_noserver;
2950         }
2951         sb_mntdata.server = server;
2952
2953         if (server->flags & NFS4_MOUNT_UNSHARED)
2954                 compare_super = NULL;
2955
2956         /* -o noac implies -o sync */
2957         if (server->flags & NFS_MOUNT_NOAC)
2958                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2959
2960         /* Get a superblock - note that we may end up sharing one that already exists */
2961         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2962         if (IS_ERR(s)) {
2963                 error = PTR_ERR(s);
2964                 goto out_err_nosb;
2965         }
2966
2967         if (s->s_fs_info != server) {
2968                 nfs_free_server(server);
2969                 server = NULL;
2970         } else {
2971                 error = nfs_bdi_register(server);
2972                 if (error)
2973                         goto error_splat_bdi;
2974         }
2975
2976         if (!s->s_root) {
2977                 /* initial superblock/root creation */
2978                 nfs4_clone_super(s, data->sb);
2979                 nfs_fscache_get_super_cookie(s, NULL, data);
2980         }
2981
2982         mntroot = nfs4_get_root(s, data->fh, dev_name);
2983         if (IS_ERR(mntroot)) {
2984                 error = PTR_ERR(mntroot);
2985                 goto error_splat_super;
2986         }
2987         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2988                 dput(mntroot);
2989                 error = -ESTALE;
2990                 goto error_splat_super;
2991         }
2992
2993         s->s_flags |= MS_ACTIVE;
2994
2995         security_sb_clone_mnt_opts(data->sb, s);
2996
2997         dprintk("<-- nfs4_xdev_mount() = 0\n");
2998         return mntroot;
2999
3000 out_err_nosb:
3001         nfs_free_server(server);
3002 out_err_noserver:
3003         dprintk("<-- nfs4_xdev_mount() = %d [error]\n", error);
3004         return ERR_PTR(error);
3005
3006 error_splat_super:
3007         if (server && !s->s_root)
3008                 bdi_unregister(&server->backing_dev_info);
3009 error_splat_bdi:
3010         deactivate_locked_super(s);
3011         dprintk("<-- nfs4_xdev_mount() = %d [splat]\n", error);
3012         return ERR_PTR(error);
3013 }
3014
3015 static struct dentry *
3016 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
3017                            const char *dev_name, void *raw_data)
3018 {
3019         struct nfs_clone_mount *data = raw_data;
3020         struct super_block *s;
3021         struct nfs_server *server;
3022         struct dentry *mntroot;
3023         struct nfs_fh *mntfh;
3024         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
3025         struct nfs_sb_mountdata sb_mntdata = {
3026                 .mntflags = flags,
3027         };
3028         int error = -ENOMEM;
3029
3030         dprintk("--> nfs4_referral_get_sb()\n");
3031
3032         mntfh = nfs_alloc_fhandle();
3033         if (mntfh == NULL)
3034                 goto out_err_nofh;
3035
3036         /* create a new volume representation */
3037         server = nfs4_create_referral_server(data, mntfh);
3038         if (IS_ERR(server)) {
3039                 error = PTR_ERR(server);
3040                 goto out_err_noserver;
3041         }
3042         sb_mntdata.server = server;
3043
3044         if (server->flags & NFS4_MOUNT_UNSHARED)
3045                 compare_super = NULL;
3046
3047         /* -o noac implies -o sync */
3048         if (server->flags & NFS_MOUNT_NOAC)
3049                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
3050
3051         /* Get a superblock - note that we may end up sharing one that already exists */
3052         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
3053         if (IS_ERR(s)) {
3054                 error = PTR_ERR(s);
3055                 goto out_err_nosb;
3056         }
3057
3058         if (s->s_fs_info != server) {
3059                 nfs_free_server(server);
3060                 server = NULL;
3061         } else {
3062                 error = nfs_bdi_register(server);
3063                 if (error)
3064                         goto error_splat_bdi;
3065         }
3066
3067         if (!s->s_root) {
3068                 /* initial superblock/root creation */
3069                 nfs4_fill_super(s);
3070                 nfs_fscache_get_super_cookie(s, NULL, data);
3071         }
3072
3073         mntroot = nfs4_get_root(s, mntfh, dev_name);
3074         if (IS_ERR(mntroot)) {
3075                 error = PTR_ERR(mntroot);
3076                 goto error_splat_super;
3077         }
3078         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3079                 dput(mntroot);
3080                 error = -ESTALE;
3081                 goto error_splat_super;
3082         }
3083
3084         s->s_flags |= MS_ACTIVE;
3085
3086         security_sb_clone_mnt_opts(data->sb, s);
3087
3088         nfs_free_fhandle(mntfh);
3089         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3090         return mntroot;
3091
3092 out_err_nosb:
3093         nfs_free_server(server);
3094 out_err_noserver:
3095         nfs_free_fhandle(mntfh);
3096 out_err_nofh:
3097         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3098         return ERR_PTR(error);
3099
3100 error_splat_super:
3101         if (server && !s->s_root)
3102                 bdi_unregister(&server->backing_dev_info);
3103 error_splat_bdi:
3104         deactivate_locked_super(s);
3105         nfs_free_fhandle(mntfh);
3106         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3107         return ERR_PTR(error);
3108 }
3109
3110 /*
3111  * Create an NFS4 server record on referral traversal
3112  */
3113 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
3114                 int flags, const char *dev_name, void *raw_data)
3115 {
3116         struct nfs_clone_mount *data = raw_data;
3117         char *export_path;
3118         struct vfsmount *root_mnt;
3119         struct dentry *res;
3120
3121         dprintk("--> nfs4_referral_mount()\n");
3122
3123         export_path = data->mnt_path;
3124         data->mnt_path = "/";
3125
3126         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3127                         flags, data, data->hostname);
3128         data->mnt_path = export_path;
3129
3130         res = nfs_follow_remote_path(root_mnt, export_path);
3131         dprintk("<-- nfs4_referral_mount() = %ld%s\n",
3132                         IS_ERR(res) ? PTR_ERR(res) : 0,
3133                         IS_ERR(res) ? " [error]" : "");
3134         return res;
3135 }
3136
3137 #endif /* CONFIG_NFS_V4 */