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
  56 #include <asm/system.h>
  57 #include <asm/uaccess.h>
  58
  59 #include "nfs4_fs.h"
  60 #include "callback.h"
  61 #include "delegation.h"
  62 #include "iostat.h"
  63 #include "internal.h"
  64 #include "fscache.h"
  65 #include "pnfs.h"
  66
  67 #define NFSDBG_FACILITY         NFSDBG_VFS
  68
  69 #ifdef CONFIG_NFS_V3
  70 #define NFS_DEFAULT_VERSION 3
  71 #else
  72 #define NFS_DEFAULT_VERSION 2
  73 #endif
  74
  75 enum {
  76         /* Mount options that take no arguments */
  77         Opt_soft, Opt_hard,
  78         Opt_posix, Opt_noposix,
  79         Opt_cto, Opt_nocto,
  80         Opt_ac, Opt_noac,
  81         Opt_lock, Opt_nolock,
  82         Opt_v2, Opt_v3, Opt_v4,
  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_nfsvers,
 101         Opt_minorversion,
 102
 103         /* Mount options that take string arguments */
 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_v2, "v2" },
 136         { Opt_v3, "v3" },
 137         { Opt_v4, "v4" },
 138         { Opt_udp, "udp" },
 139         { Opt_tcp, "tcp" },
 140         { Opt_rdma, "rdma" },
 141         { Opt_acl, "acl" },
 142         { Opt_noacl, "noacl" },
 143         { Opt_rdirplus, "rdirplus" },
 144         { Opt_nordirplus, "nordirplus" },
 145         { Opt_sharecache, "sharecache" },
 146         { Opt_nosharecache, "nosharecache" },
 147         { Opt_resvport, "resvport" },
 148         { Opt_noresvport, "noresvport" },
 149         { Opt_fscache, "fsc" },
 150         { Opt_nofscache, "nofsc" },
 151
 152         { Opt_port, "port=%s" },
 153         { Opt_rsize, "rsize=%s" },
 154         { Opt_wsize, "wsize=%s" },
 155         { Opt_bsize, "bsize=%s" },
 156         { Opt_timeo, "timeo=%s" },
 157         { Opt_retrans, "retrans=%s" },
 158         { Opt_acregmin, "acregmin=%s" },
 159         { Opt_acregmax, "acregmax=%s" },
 160         { Opt_acdirmin, "acdirmin=%s" },
 161         { Opt_acdirmax, "acdirmax=%s" },
 162         { Opt_actimeo, "actimeo=%s" },
 163         { Opt_namelen, "namlen=%s" },
 164         { Opt_mountport, "mountport=%s" },
 165         { Opt_mountvers, "mountvers=%s" },
 166         { Opt_nfsvers, "nfsvers=%s" },
 167         { Opt_nfsvers, "vers=%s" },
 168         { Opt_minorversion, "minorversion=%s" },
 169
 170         { Opt_sec, "sec=%s" },
 171         { Opt_proto, "proto=%s" },
 172         { Opt_mountproto, "mountproto=%s" },
 173         { Opt_addr, "addr=%s" },
 174         { Opt_clientaddr, "clientaddr=%s" },
 175         { Opt_mounthost, "mounthost=%s" },
 176         { Opt_mountaddr, "mountaddr=%s" },
 177
 178         { Opt_lookupcache, "lookupcache=%s" },
 179         { Opt_fscache_uniq, "fsc=%s" },
 180         { Opt_local_lock, "local_lock=%s" },
 181
 182         { Opt_err, NULL }
 183 };
 184
 185 enum {
 186         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 187
 188         Opt_xprt_err
 189 };
 190
 191 static const match_table_t nfs_xprt_protocol_tokens = {
 192         { Opt_xprt_udp, "udp" },
 193         { Opt_xprt_udp6, "udp6" },
 194         { Opt_xprt_tcp, "tcp" },
 195         { Opt_xprt_tcp6, "tcp6" },
 196         { Opt_xprt_rdma, "rdma" },
 197
 198         { Opt_xprt_err, NULL }
 199 };
 200
 201 enum {
 202         Opt_sec_none, Opt_sec_sys,
 203         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 204         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 205         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 206
 207         Opt_sec_err
 208 };
 209
 210 static const match_table_t nfs_secflavor_tokens = {
 211         { Opt_sec_none, "none" },
 212         { Opt_sec_none, "null" },
 213         { Opt_sec_sys, "sys" },
 214
 215         { Opt_sec_krb5, "krb5" },
 216         { Opt_sec_krb5i, "krb5i" },
 217         { Opt_sec_krb5p, "krb5p" },
 218
 219         { Opt_sec_lkey, "lkey" },
 220         { Opt_sec_lkeyi, "lkeyi" },
 221         { Opt_sec_lkeyp, "lkeyp" },
 222
 223         { Opt_sec_spkm, "spkm3" },
 224         { Opt_sec_spkmi, "spkm3i" },
 225         { Opt_sec_spkmp, "spkm3p" },
 226
 227         { Opt_sec_err, NULL }
 228 };
 229
 230 enum {
 231         Opt_lookupcache_all, Opt_lookupcache_positive,
 232         Opt_lookupcache_none,
 233
 234         Opt_lookupcache_err
 235 };
 236
 237 static match_table_t nfs_lookupcache_tokens = {
 238         { Opt_lookupcache_all, "all" },
 239         { Opt_lookupcache_positive, "pos" },
 240         { Opt_lookupcache_positive, "positive" },
 241         { Opt_lookupcache_none, "none" },
 242
 243         { Opt_lookupcache_err, NULL }
 244 };
 245
 246 enum {
 247         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 248         Opt_local_lock_none,
 249
 250         Opt_local_lock_err
 251 };
 252
 253 static match_table_t nfs_local_lock_tokens = {
 254         { Opt_local_lock_all, "all" },
 255         { Opt_local_lock_flock, "flock" },
 256         { Opt_local_lock_posix, "posix" },
 257         { Opt_local_lock_none, "none" },
 258
 259         { Opt_local_lock_err, NULL }
 260 };
 261
 262
 263 static void nfs_umount_begin(struct super_block *);
 264 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 265 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 266 static int  nfs_show_devname(struct seq_file *, struct dentry *);
 267 static int  nfs_show_path(struct seq_file *, struct vfsmount *);
 268 static int  nfs_show_stats(struct seq_file *, struct dentry *);
 269 static struct dentry *nfs_fs_mount(struct file_system_type *,
 270                 int, const char *, void *);
 271 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 272                 int flags, const char *dev_name, void *raw_data);
 273 static void nfs_put_super(struct super_block *);
 274 static void nfs_kill_super(struct super_block *);
 275 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 276
 277 static struct file_system_type nfs_fs_type = {
 278         .owner          = THIS_MODULE,
 279         .name           = "nfs",
 280         .mount          = nfs_fs_mount,
 281         .kill_sb        = nfs_kill_super,
 282         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 283 };
 284
 285 struct file_system_type nfs_xdev_fs_type = {
 286         .owner          = THIS_MODULE,
 287         .name           = "nfs",
 288         .mount          = nfs_xdev_mount,
 289         .kill_sb        = nfs_kill_super,
 290         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 291 };
 292
 293 static const struct super_operations nfs_sops = {
 294         .alloc_inode    = nfs_alloc_inode,
 295         .destroy_inode  = nfs_destroy_inode,
 296         .write_inode    = nfs_write_inode,
 297         .put_super      = nfs_put_super,
 298         .statfs         = nfs_statfs,
 299         .evict_inode    = nfs_evict_inode,
 300         .umount_begin   = nfs_umount_begin,
 301         .show_options   = nfs_show_options,
 302         .show_devname   = nfs_show_devname,
 303         .show_path      = nfs_show_path,
 304         .show_stats     = nfs_show_stats,
 305         .remount_fs     = nfs_remount,
 306 };
 307
 308 #ifdef CONFIG_NFS_V4
 309 static int nfs4_validate_text_mount_data(void *options,
 310         struct nfs_parsed_mount_data *args, const char *dev_name);
 311 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
 312         struct nfs_parsed_mount_data *data);
 313 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
 314         int flags, const char *dev_name, void *raw_data);
 315 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
 316         int flags, const char *dev_name, void *raw_data);
 317 static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
 318         int flags, const char *dev_name, void *raw_data);
 319 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
 320         int flags, const char *dev_name, void *raw_data);
 321 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
 322         int flags, const char *dev_name, void *raw_data);
 323 static void nfs4_kill_super(struct super_block *sb);
 324
 325 static struct file_system_type nfs4_fs_type = {
 326         .owner          = THIS_MODULE,
 327         .name           = "nfs4",
 328         .mount          = nfs4_mount,
 329         .kill_sb        = nfs4_kill_super,
 330         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 331 };
 332
 333 static struct file_system_type nfs4_remote_fs_type = {
 334         .owner          = THIS_MODULE,
 335         .name           = "nfs4",
 336         .mount          = nfs4_remote_mount,
 337         .kill_sb        = nfs4_kill_super,
 338         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 339 };
 340
 341 struct file_system_type nfs4_xdev_fs_type = {
 342         .owner          = THIS_MODULE,
 343         .name           = "nfs4",
 344         .mount          = nfs4_xdev_mount,
 345         .kill_sb        = nfs4_kill_super,
 346         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 347 };
 348
 349 static struct file_system_type nfs4_remote_referral_fs_type = {
 350         .owner          = THIS_MODULE,
 351         .name           = "nfs4",
 352         .mount          = nfs4_remote_referral_mount,
 353         .kill_sb        = nfs4_kill_super,
 354         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 355 };
 356
 357 struct file_system_type nfs4_referral_fs_type = {
 358         .owner          = THIS_MODULE,
 359         .name           = "nfs4",
 360         .mount          = nfs4_referral_mount,
 361         .kill_sb        = nfs4_kill_super,
 362         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 363 };
 364
 365 static const struct super_operations nfs4_sops = {
 366         .alloc_inode    = nfs_alloc_inode,
 367         .destroy_inode  = nfs_destroy_inode,
 368         .write_inode    = nfs_write_inode,
 369         .put_super      = nfs_put_super,
 370         .statfs         = nfs_statfs,
 371         .evict_inode    = nfs4_evict_inode,
 372         .umount_begin   = nfs_umount_begin,
 373         .show_options   = nfs_show_options,
 374         .show_devname   = nfs_show_devname,
 375         .show_path      = nfs_show_path,
 376         .show_stats     = nfs_show_stats,
 377         .remount_fs     = nfs_remount,
 378 };
 379 #endif
 380
 381 static struct shrinker acl_shrinker = {
 382         .shrink         = nfs_access_cache_shrinker,
 383         .seeks          = DEFAULT_SEEKS,
 384 };
 385
 386 /*
 387  * Register the NFS filesystems
 388  */
 389 int __init register_nfs_fs(void)
 390 {
 391         int ret;
 392
 393         ret = register_filesystem(&nfs_fs_type);
 394         if (ret < 0)
 395                 goto error_0;
 396
 397         ret = nfs_register_sysctl();
 398         if (ret < 0)
 399                 goto error_1;
 400 #ifdef CONFIG_NFS_V4
 401         ret = register_filesystem(&nfs4_fs_type);
 402         if (ret < 0)
 403                 goto error_2;
 404 #endif
 405         register_shrinker(&acl_shrinker);
 406         return 0;
 407
 408 #ifdef CONFIG_NFS_V4
 409 error_2:
 410         nfs_unregister_sysctl();
 411 #endif
 412 error_1:
 413         unregister_filesystem(&nfs_fs_type);
 414 error_0:
 415         return ret;
 416 }
 417
 418 /*
 419  * Unregister the NFS filesystems
 420  */
 421 void __exit unregister_nfs_fs(void)
 422 {
 423         unregister_shrinker(&acl_shrinker);
 424 #ifdef CONFIG_NFS_V4
 425         unregister_filesystem(&nfs4_fs_type);
 426 #endif
 427         nfs_unregister_sysctl();
 428         unregister_filesystem(&nfs_fs_type);
 429 }
 430
 431 void nfs_sb_active(struct super_block *sb)
 432 {
 433         struct nfs_server *server = NFS_SB(sb);
 434
 435         if (atomic_inc_return(&server->active) == 1)
 436                 atomic_inc(&sb->s_active);
 437 }
 438
 439 void nfs_sb_deactive(struct super_block *sb)
 440 {
 441         struct nfs_server *server = NFS_SB(sb);
 442
 443         if (atomic_dec_and_test(&server->active))
 444                 deactivate_super(sb);
 445 }
 446
 447 /*
 448  * Deliver file system statistics to userspace
 449  */
 450 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 451 {
 452         struct nfs_server *server = NFS_SB(dentry->d_sb);
 453         unsigned char blockbits;
 454         unsigned long blockres;
 455         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 456         struct nfs_fsstat res;
 457         int error = -ENOMEM;
 458
 459         res.fattr = nfs_alloc_fattr();
 460         if (res.fattr == NULL)
 461                 goto out_err;
 462
 463         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 464         if (unlikely(error == -ESTALE)) {
 465                 struct dentry *pd_dentry;
 466
 467                 pd_dentry = dget_parent(dentry);
 468                 if (pd_dentry != NULL) {
 469                         nfs_zap_caches(pd_dentry->d_inode);
 470                         dput(pd_dentry);
 471                 }
 472         }
 473         nfs_free_fattr(res.fattr);
 474         if (error < 0)
 475                 goto out_err;
 476
 477         buf->f_type = NFS_SUPER_MAGIC;
 478
 479         /*
 480          * Current versions of glibc do not correctly handle the
 481          * case where f_frsize != f_bsize.  Eventually we want to
 482          * report the value of wtmult in this field.
 483          */
 484         buf->f_frsize = dentry->d_sb->s_blocksize;
 485
 486         /*
 487          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 488          * are reported in units of f_frsize.  Linux hasn't had
 489          * an f_frsize field in its statfs struct until recently,
 490          * thus historically Linux's sys_statfs reports these
 491          * fields in units of f_bsize.
 492          */
 493         buf->f_bsize = dentry->d_sb->s_blocksize;
 494         blockbits = dentry->d_sb->s_blocksize_bits;
 495         blockres = (1 << blockbits) - 1;
 496         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 497         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 498         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 499
 500         buf->f_files = res.tfiles;
 501         buf->f_ffree = res.afiles;
 502
 503         buf->f_namelen = server->namelen;
 504
 505         return 0;
 506
 507  out_err:
 508         dprintk("%s: statfs error = %d\n", __func__, -error);
 509         return error;
 510 }
 511
 512 /*
 513  * Map the security flavour number to a name
 514  */
 515 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 516 {
 517         static const struct {
 518                 rpc_authflavor_t flavour;
 519                 const char *str;
 520         } sec_flavours[] = {
 521                 { RPC_AUTH_NULL, "null" },
 522                 { RPC_AUTH_UNIX, "sys" },
 523                 { RPC_AUTH_GSS_KRB5, "krb5" },
 524                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 525                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 526                 { RPC_AUTH_GSS_LKEY, "lkey" },
 527                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 528                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 529                 { RPC_AUTH_GSS_SPKM, "spkm" },
 530                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 531                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 532                 { UINT_MAX, "unknown" }
 533         };
 534         int i;
 535
 536         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 537                 if (sec_flavours[i].flavour == flavour)
 538                         break;
 539         }
 540         return sec_flavours[i].str;
 541 }
 542
 543 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 544                                   int showdefaults)
 545 {
 546         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 547
 548         seq_printf(m, ",mountproto=");
 549         switch (sap->sa_family) {
 550         case AF_INET:
 551                 switch (nfss->mountd_protocol) {
 552                 case IPPROTO_UDP:
 553                         seq_printf(m, RPCBIND_NETID_UDP);
 554                         break;
 555                 case IPPROTO_TCP:
 556                         seq_printf(m, RPCBIND_NETID_TCP);
 557                         break;
 558                 default:
 559                         if (showdefaults)
 560                                 seq_printf(m, "auto");
 561                 }
 562                 break;
 563         case AF_INET6:
 564                 switch (nfss->mountd_protocol) {
 565                 case IPPROTO_UDP:
 566                         seq_printf(m, RPCBIND_NETID_UDP6);
 567                         break;
 568                 case IPPROTO_TCP:
 569                         seq_printf(m, RPCBIND_NETID_TCP6);
 570                         break;
 571                 default:
 572                         if (showdefaults)
 573                                 seq_printf(m, "auto");
 574                 }
 575                 break;
 576         default:
 577                 if (showdefaults)
 578                         seq_printf(m, "auto");
 579         }
 580 }
 581
 582 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 583                                     int showdefaults)
 584 {
 585         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 586
 587         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 588                 return;
 589
 590         switch (sap->sa_family) {
 591         case AF_INET: {
 592                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 593                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 594                 break;
 595         }
 596         case AF_INET6: {
 597                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 598                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 599                 break;
 600         }
 601         default:
 602                 if (showdefaults)
 603                         seq_printf(m, ",mountaddr=unspecified");
 604         }
 605
 606         if (nfss->mountd_version || showdefaults)
 607                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 608         if ((nfss->mountd_port &&
 609                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 610                 showdefaults)
 611                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 612
 613         nfs_show_mountd_netid(m, nfss, showdefaults);
 614 }
 615
 616 #ifdef CONFIG_NFS_V4
 617 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 618                                     int showdefaults)
 619 {
 620         struct nfs_client *clp = nfss->nfs_client;
 621
 622         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 623         seq_printf(m, ",minorversion=%u", clp->cl_minorversion);
 624 }
 625 #else
 626 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 627                                     int showdefaults)
 628 {
 629 }
 630 #endif
 631
 632 /*
 633  * Describe the mount options in force on this server representation
 634  */
 635 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 636                                    int showdefaults)
 637 {
 638         static const struct proc_nfs_info {
 639                 int flag;
 640                 const char *str;
 641                 const char *nostr;
 642         } nfs_info[] = {
 643                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 644                 { NFS_MOUNT_POSIX, ",posix", "" },
 645                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 646                 { NFS_MOUNT_NOAC, ",noac", "" },
 647                 { NFS_MOUNT_NONLM, ",nolock", "" },
 648                 { NFS_MOUNT_NOACL, ",noacl", "" },
 649                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 650                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 651                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 652                 { 0, NULL, NULL }
 653         };
 654         const struct proc_nfs_info *nfs_infop;
 655         struct nfs_client *clp = nfss->nfs_client;
 656         u32 version = clp->rpc_ops->version;
 657         int local_flock, local_fcntl;
 658
 659         seq_printf(m, ",vers=%u", version);
 660         seq_printf(m, ",rsize=%u", nfss->rsize);
 661         seq_printf(m, ",wsize=%u", nfss->wsize);
 662         if (nfss->bsize != 0)
 663                 seq_printf(m, ",bsize=%u", nfss->bsize);
 664         seq_printf(m, ",namlen=%u", nfss->namelen);
 665         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 666                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 667         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 668                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 669         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 670                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 671         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 672                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 673         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 674                 if (nfss->flags & nfs_infop->flag)
 675                         seq_puts(m, nfs_infop->str);
 676                 else
 677                         seq_puts(m, nfs_infop->nostr);
 678         }
 679         seq_printf(m, ",proto=%s",
 680                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 681         if (version == 4) {
 682                 if (nfss->port != NFS_PORT)
 683                         seq_printf(m, ",port=%u", nfss->port);
 684         } else
 685                 if (nfss->port)
 686                         seq_printf(m, ",port=%u", nfss->port);
 687
 688         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 689         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 690         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 691
 692         if (version != 4)
 693                 nfs_show_mountd_options(m, nfss, showdefaults);
 694         else
 695                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 696
 697         if (nfss->options & NFS_OPTION_FSCACHE)
 698                 seq_printf(m, ",fsc");
 699
 700         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 701                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 702                         seq_printf(m, ",lookupcache=none");
 703                 else
 704                         seq_printf(m, ",lookupcache=pos");
 705         }
 706
 707         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 708         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 709
 710         if (!local_flock && !local_fcntl)
 711                 seq_printf(m, ",local_lock=none");
 712         else if (local_flock && local_fcntl)
 713                 seq_printf(m, ",local_lock=all");
 714         else if (local_flock)
 715                 seq_printf(m, ",local_lock=flock");
 716         else
 717                 seq_printf(m, ",local_lock=posix");
 718 }
 719
 720 /*
 721  * Describe the mount options on this VFS mountpoint
 722  */
 723 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 724 {
 725         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 726
 727         nfs_show_mount_options(m, nfss, 0);
 728
 729         seq_printf(m, ",addr=%s",
 730                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 731                                                         RPC_DISPLAY_ADDR));
 732
 733         return 0;
 734 }
 735
 736 #ifdef CONFIG_NFS_V4
 737 #ifdef CONFIG_NFS_V4_1
 738 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 739 {
 740         if (nfs4_has_session(server->nfs_client))
 741                 seq_printf(m, ",sessions");
 742 }
 743 #else
 744 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 745 #endif
 746 #endif
 747
 748 #ifdef CONFIG_NFS_V4
 749 #ifdef CONFIG_NFS_V4_1
 750 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 751 {
 752         seq_printf(m, ",pnfs=");
 753         if (server->pnfs_curr_ld)
 754                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 755         else
 756                 seq_printf(m, "not configured");
 757 }
 758 #else
 759 static void show_pnfs(struct seq_file *m, struct nfs_server *server) {}
 760 #endif
 761 #endif
 762
 763 static int nfs_show_devname(struct seq_file *m, struct dentry *root)
 764 {
 765         char *page = (char *) __get_free_page(GFP_KERNEL);
 766         char *devname, *dummy;
 767         int err = 0;
 768         if (!page)
 769                 return -ENOMEM;
 770         devname = nfs_path(&dummy, root, page, PAGE_SIZE);
 771         if (IS_ERR(devname))
 772                 err = PTR_ERR(devname);
 773         else
 774                 seq_escape(m, devname, " \t\n\\");
 775         free_page((unsigned long)page);
 776         return err;
 777 }
 778
 779 static int nfs_show_path(struct seq_file *m, struct vfsmount *mnt)
 780 {
 781         seq_puts(m, "/");
 782         return 0;
 783 }
 784
 785 /*
 786  * Present statistical information for this VFS mountpoint
 787  */
 788 static int nfs_show_stats(struct seq_file *m, struct dentry *root)
 789 {
 790         int i, cpu;
 791         struct nfs_server *nfss = NFS_SB(root->d_sb);
 792         struct rpc_auth *auth = nfss->client->cl_auth;
 793         struct nfs_iostats totals = { };
 794
 795         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 796
 797         /*
 798          * Display all mount option settings
 799          */
 800         seq_printf(m, "\n\topts:\t");
 801         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 802         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 803         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 804         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 805         nfs_show_mount_options(m, nfss, 1);
 806
 807         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 808
 809         seq_printf(m, "\n\tcaps:\t");
 810         seq_printf(m, "caps=0x%x", nfss->caps);
 811         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 812         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 813         seq_printf(m, ",bsize=%u", nfss->bsize);
 814         seq_printf(m, ",namlen=%u", nfss->namelen);
 815
 816 #ifdef CONFIG_NFS_V4
 817         if (nfss->nfs_client->rpc_ops->version == 4) {
 818                 seq_printf(m, "\n\tnfsv4:\t");
 819                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 820                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 821                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 822                 show_sessions(m, nfss);
 823                 show_pnfs(m, nfss);
 824         }
 825 #endif
 826
 827         /*
 828          * Display security flavor in effect for this mount
 829          */
 830         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 831         if (auth->au_flavor)
 832                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 833
 834         /*
 835          * Display superblock I/O counters
 836          */
 837         for_each_possible_cpu(cpu) {
 838                 struct nfs_iostats *stats;
 839
 840                 preempt_disable();
 841                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 842
 843                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 844                         totals.events[i] += stats->events[i];
 845                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 846                         totals.bytes[i] += stats->bytes[i];
 847 #ifdef CONFIG_NFS_FSCACHE
 848                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 849                         totals.fscache[i] += stats->fscache[i];
 850 #endif
 851
 852                 preempt_enable();
 853         }
 854
 855         seq_printf(m, "\n\tevents:\t");
 856         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 857                 seq_printf(m, "%lu ", totals.events[i]);
 858         seq_printf(m, "\n\tbytes:\t");
 859         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 860                 seq_printf(m, "%Lu ", totals.bytes[i]);
 861 #ifdef CONFIG_NFS_FSCACHE
 862         if (nfss->options & NFS_OPTION_FSCACHE) {
 863                 seq_printf(m, "\n\tfsc:\t");
 864                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 865                         seq_printf(m, "%Lu ", totals.bytes[i]);
 866         }
 867 #endif
 868         seq_printf(m, "\n");
 869
 870         rpc_print_iostats(m, nfss->client);
 871
 872         return 0;
 873 }
 874
 875 /*
 876  * Begin unmount by attempting to remove all automounted mountpoints we added
 877  * in response to xdev traversals and referrals
 878  */
 879 static void nfs_umount_begin(struct super_block *sb)
 880 {
 881         struct nfs_server *server;
 882         struct rpc_clnt *rpc;
 883
 884         server = NFS_SB(sb);
 885         /* -EIO all pending I/O */
 886         rpc = server->client_acl;
 887         if (!IS_ERR(rpc))
 888                 rpc_killall_tasks(rpc);
 889         rpc = server->client;
 890         if (!IS_ERR(rpc))
 891                 rpc_killall_tasks(rpc);
 892 }
 893
 894 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
 895 {
 896         struct nfs_parsed_mount_data *data;
 897
 898         data = kzalloc(sizeof(*data), GFP_KERNEL);
 899         if (data) {
 900                 data->acregmin          = NFS_DEF_ACREGMIN;
 901                 data->acregmax          = NFS_DEF_ACREGMAX;
 902                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 903                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 904                 data->mount_server.port = NFS_UNSPEC_PORT;
 905                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 906                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 907                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 908                 data->auth_flavor_len   = 1;
 909                 data->version           = version;
 910                 data->minorversion      = 0;
 911         }
 912         return data;
 913 }
 914
 915 /*
 916  * Sanity-check a server address provided by the mount command.
 917  *
 918  * Address family must be initialized, and address must not be
 919  * the ANY address for that family.
 920  */
 921 static int nfs_verify_server_address(struct sockaddr *addr)
 922 {
 923         switch (addr->sa_family) {
 924         case AF_INET: {
 925                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 926                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 927         }
 928         case AF_INET6: {
 929                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 930                 return !ipv6_addr_any(sa);
 931         }
 932         }
 933
 934         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 935         return 0;
 936 }
 937
 938 /*
 939  * Select between a default port value and a user-specified port value.
 940  * If a zero value is set, then autobind will be used.
 941  */
 942 static void nfs_set_port(struct sockaddr *sap, int *port,
 943                                  const unsigned short default_port)
 944 {
 945         if (*port == NFS_UNSPEC_PORT)
 946                 *port = default_port;
 947
 948         rpc_set_port(sap, *port);
 949 }
 950
 951 /*
 952  * Sanity check the NFS transport protocol.
 953  *
 954  */
 955 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 956 {
 957         switch (mnt->nfs_server.protocol) {
 958         case XPRT_TRANSPORT_UDP:
 959         case XPRT_TRANSPORT_TCP:
 960         case XPRT_TRANSPORT_RDMA:
 961                 break;
 962         default:
 963                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 964         }
 965 }
 966
 967 /*
 968  * For text based NFSv2/v3 mounts, the mount protocol transport default
 969  * settings should depend upon the specified NFS transport.
 970  */
 971 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 972 {
 973         nfs_validate_transport_protocol(mnt);
 974
 975         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 976             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 977                         return;
 978         switch (mnt->nfs_server.protocol) {
 979         case XPRT_TRANSPORT_UDP:
 980                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 981                 break;
 982         case XPRT_TRANSPORT_TCP:
 983         case XPRT_TRANSPORT_RDMA:
 984                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 985         }
 986 }
 987
 988 /*
 989  * Parse the value of the 'sec=' option.
 990  */
 991 static int nfs_parse_security_flavors(char *value,
 992                                       struct nfs_parsed_mount_data *mnt)
 993 {
 994         substring_t args[MAX_OPT_ARGS];
 995
 996         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 997
 998         switch (match_token(value, nfs_secflavor_tokens, args)) {
 999         case Opt_sec_none:
1000                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1001                 break;
1002         case Opt_sec_sys:
1003                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1004                 break;
1005         case Opt_sec_krb5:
1006                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1007                 break;
1008         case Opt_sec_krb5i:
1009                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1010                 break;
1011         case Opt_sec_krb5p:
1012                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1013                 break;
1014         case Opt_sec_lkey:
1015                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1016                 break;
1017         case Opt_sec_lkeyi:
1018                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1019                 break;
1020         case Opt_sec_lkeyp:
1021                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1022                 break;
1023         case Opt_sec_spkm:
1024                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1025                 break;
1026         case Opt_sec_spkmi:
1027                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1028                 break;
1029         case Opt_sec_spkmp:
1030                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1031                 break;
1032         default:
1033                 return 0;
1034         }
1035
1036         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1037         mnt->auth_flavor_len = 1;
1038         return 1;
1039 }
1040
1041 static int nfs_get_option_str(substring_t args[], char **option)
1042 {
1043         kfree(*option);
1044         *option = match_strdup(args);
1045         return !option;
1046 }
1047
1048 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1049 {
1050         int rc;
1051         char *string;
1052
1053         string = match_strdup(args);
1054         if (string == NULL)
1055                 return -ENOMEM;
1056         rc = strict_strtoul(string, 10, option);
1057         kfree(string);
1058
1059         return rc;
1060 }
1061
1062 /*
1063  * Error-check and convert a string of mount options from user space into
1064  * a data structure.  The whole mount string is processed; bad options are
1065  * skipped as they are encountered.  If there were no errors, return 1;
1066  * otherwise return 0 (zero).
1067  */
1068 static int nfs_parse_mount_options(char *raw,
1069                                    struct nfs_parsed_mount_data *mnt)
1070 {
1071         char *p, *string, *secdata;
1072         int rc, sloppy = 0, invalid_option = 0;
1073         unsigned short protofamily = AF_UNSPEC;
1074         unsigned short mountfamily = AF_UNSPEC;
1075
1076         if (!raw) {
1077                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1078                 return 1;
1079         }
1080         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1081
1082         secdata = alloc_secdata();
1083         if (!secdata)
1084                 goto out_nomem;
1085
1086         rc = security_sb_copy_data(raw, secdata);
1087         if (rc)
1088                 goto out_security_failure;
1089
1090         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1091         if (rc)
1092                 goto out_security_failure;
1093
1094         free_secdata(secdata);
1095
1096         while ((p = strsep(&raw, ",")) != NULL) {
1097                 substring_t args[MAX_OPT_ARGS];
1098                 unsigned long option;
1099                 int token;
1100
1101                 if (!*p)
1102                         continue;
1103
1104                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1105
1106                 token = match_token(p, nfs_mount_option_tokens, args);
1107                 switch (token) {
1108
1109                 /*
1110                  * boolean options:  foo/nofoo
1111                  */
1112                 case Opt_soft:
1113                         mnt->flags |= NFS_MOUNT_SOFT;
1114                         break;
1115                 case Opt_hard:
1116                         mnt->flags &= ~NFS_MOUNT_SOFT;
1117                         break;
1118                 case Opt_posix:
1119                         mnt->flags |= NFS_MOUNT_POSIX;
1120                         break;
1121                 case Opt_noposix:
1122                         mnt->flags &= ~NFS_MOUNT_POSIX;
1123                         break;
1124                 case Opt_cto:
1125                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1126                         break;
1127                 case Opt_nocto:
1128                         mnt->flags |= NFS_MOUNT_NOCTO;
1129                         break;
1130                 case Opt_ac:
1131                         mnt->flags &= ~NFS_MOUNT_NOAC;
1132                         break;
1133                 case Opt_noac:
1134                         mnt->flags |= NFS_MOUNT_NOAC;
1135                         break;
1136                 case Opt_lock:
1137                         mnt->flags &= ~NFS_MOUNT_NONLM;
1138                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1139                                         NFS_MOUNT_LOCAL_FCNTL);
1140                         break;
1141                 case Opt_nolock:
1142                         mnt->flags |= NFS_MOUNT_NONLM;
1143                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1144                                        NFS_MOUNT_LOCAL_FCNTL);
1145                         break;
1146                 case Opt_v2:
1147                         mnt->flags &= ~NFS_MOUNT_VER3;
1148                         mnt->version = 2;
1149                         break;
1150                 case Opt_v3:
1151                         mnt->flags |= NFS_MOUNT_VER3;
1152                         mnt->version = 3;
1153                         break;
1154                 case Opt_v4:
1155                         mnt->flags &= ~NFS_MOUNT_VER3;
1156                         mnt->version = 4;
1157                         break;
1158                 case Opt_udp:
1159                         mnt->flags &= ~NFS_MOUNT_TCP;
1160                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1161                         break;
1162                 case Opt_tcp:
1163                         mnt->flags |= NFS_MOUNT_TCP;
1164                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1165                         break;
1166                 case Opt_rdma:
1167                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1168                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1169                         xprt_load_transport(p);
1170                         break;
1171                 case Opt_acl:
1172                         mnt->flags &= ~NFS_MOUNT_NOACL;
1173                         break;
1174                 case Opt_noacl:
1175                         mnt->flags |= NFS_MOUNT_NOACL;
1176                         break;
1177                 case Opt_rdirplus:
1178                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1179                         break;
1180                 case Opt_nordirplus:
1181                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1182                         break;
1183                 case Opt_sharecache:
1184                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1185                         break;
1186                 case Opt_nosharecache:
1187                         mnt->flags |= NFS_MOUNT_UNSHARED;
1188                         break;
1189                 case Opt_resvport:
1190                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1191                         break;
1192                 case Opt_noresvport:
1193                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1194                         break;
1195                 case Opt_fscache:
1196                         mnt->options |= NFS_OPTION_FSCACHE;
1197                         kfree(mnt->fscache_uniq);
1198                         mnt->fscache_uniq = NULL;
1199                         break;
1200                 case Opt_nofscache:
1201                         mnt->options &= ~NFS_OPTION_FSCACHE;
1202                         kfree(mnt->fscache_uniq);
1203                         mnt->fscache_uniq = NULL;
1204                         break;
1205
1206                 /*
1207                  * options that take numeric values
1208                  */
1209                 case Opt_port:
1210                         if (nfs_get_option_ul(args, &option) ||
1211                             option > USHRT_MAX)
1212                                 goto out_invalid_value;
1213                         mnt->nfs_server.port = option;
1214                         break;
1215                 case Opt_rsize:
1216                         if (nfs_get_option_ul(args, &option))
1217                                 goto out_invalid_value;
1218                         mnt->rsize = option;
1219                         break;
1220                 case Opt_wsize:
1221                         if (nfs_get_option_ul(args, &option))
1222                                 goto out_invalid_value;
1223                         mnt->wsize = option;
1224                         break;
1225                 case Opt_bsize:
1226                         if (nfs_get_option_ul(args, &option))
1227                                 goto out_invalid_value;
1228                         mnt->bsize = option;
1229                         break;
1230                 case Opt_timeo:
1231                         if (nfs_get_option_ul(args, &option) || option == 0)
1232                                 goto out_invalid_value;
1233                         mnt->timeo = option;
1234                         break;
1235                 case Opt_retrans:
1236                         if (nfs_get_option_ul(args, &option) || option == 0)
1237                                 goto out_invalid_value;
1238                         mnt->retrans = option;
1239                         break;
1240                 case Opt_acregmin:
1241                         if (nfs_get_option_ul(args, &option))
1242                                 goto out_invalid_value;
1243                         mnt->acregmin = option;
1244                         break;
1245                 case Opt_acregmax:
1246                         if (nfs_get_option_ul(args, &option))
1247                                 goto out_invalid_value;
1248                         mnt->acregmax = option;
1249                         break;
1250                 case Opt_acdirmin:
1251                         if (nfs_get_option_ul(args, &option))
1252                                 goto out_invalid_value;
1253                         mnt->acdirmin = option;
1254                         break;
1255                 case Opt_acdirmax:
1256                         if (nfs_get_option_ul(args, &option))
1257                                 goto out_invalid_value;
1258                         mnt->acdirmax = option;
1259                         break;
1260                 case Opt_actimeo:
1261                         if (nfs_get_option_ul(args, &option))
1262                                 goto out_invalid_value;
1263                         mnt->acregmin = mnt->acregmax =
1264                         mnt->acdirmin = mnt->acdirmax = option;
1265                         break;
1266                 case Opt_namelen:
1267                         if (nfs_get_option_ul(args, &option))
1268                                 goto out_invalid_value;
1269                         mnt->namlen = option;
1270                         break;
1271                 case Opt_mountport:
1272                         if (nfs_get_option_ul(args, &option) ||
1273                             option > USHRT_MAX)
1274                                 goto out_invalid_value;
1275                         mnt->mount_server.port = option;
1276                         break;
1277                 case Opt_mountvers:
1278                         if (nfs_get_option_ul(args, &option) ||
1279                             option < NFS_MNT_VERSION ||
1280                             option > NFS_MNT3_VERSION)
1281                                 goto out_invalid_value;
1282                         mnt->mount_server.version = option;
1283                         break;
1284                 case Opt_nfsvers:
1285                         if (nfs_get_option_ul(args, &option))
1286                                 goto out_invalid_value;
1287                         switch (option) {
1288                         case NFS2_VERSION:
1289                                 mnt->flags &= ~NFS_MOUNT_VER3;
1290                                 mnt->version = 2;
1291                                 break;
1292                         case NFS3_VERSION:
1293                                 mnt->flags |= NFS_MOUNT_VER3;
1294                                 mnt->version = 3;
1295                                 break;
1296                         case NFS4_VERSION:
1297                                 mnt->flags &= ~NFS_MOUNT_VER3;
1298                                 mnt->version = 4;
1299                                 break;
1300                         default:
1301                                 goto out_invalid_value;
1302                         }
1303                         break;
1304                 case Opt_minorversion:
1305                         if (nfs_get_option_ul(args, &option))
1306                                 goto out_invalid_value;
1307                         if (option > NFS4_MAX_MINOR_VERSION)
1308                                 goto out_invalid_value;
1309                         mnt->minorversion = option;
1310                         break;
1311
1312                 /*
1313                  * options that take text values
1314                  */
1315                 case Opt_sec:
1316                         string = match_strdup(args);
1317                         if (string == NULL)
1318                                 goto out_nomem;
1319                         rc = nfs_parse_security_flavors(string, mnt);
1320                         kfree(string);
1321                         if (!rc) {
1322                                 dfprintk(MOUNT, "NFS:   unrecognized "
1323                                                 "security flavor\n");
1324                                 return 0;
1325                         }
1326                         break;
1327                 case Opt_proto:
1328                         string = match_strdup(args);
1329                         if (string == NULL)
1330                                 goto out_nomem;
1331                         token = match_token(string,
1332                                             nfs_xprt_protocol_tokens, args);
1333
1334                         protofamily = AF_INET;
1335                         switch (token) {
1336                         case Opt_xprt_udp6:
1337                                 protofamily = AF_INET6;
1338                         case Opt_xprt_udp:
1339                                 mnt->flags &= ~NFS_MOUNT_TCP;
1340                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1341                                 break;
1342                         case Opt_xprt_tcp6:
1343                                 protofamily = AF_INET6;
1344                         case Opt_xprt_tcp:
1345                                 mnt->flags |= NFS_MOUNT_TCP;
1346                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1347                                 break;
1348                         case Opt_xprt_rdma:
1349                                 /* vector side protocols to TCP */
1350                                 mnt->flags |= NFS_MOUNT_TCP;
1351                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1352                                 xprt_load_transport(string);
1353                                 break;
1354                         default:
1355                                 dfprintk(MOUNT, "NFS:   unrecognized "
1356                                                 "transport protocol\n");
1357                                 kfree(string);
1358                                 return 0;
1359                         }
1360                         kfree(string);
1361                         break;
1362                 case Opt_mountproto:
1363                         string = match_strdup(args);
1364                         if (string == NULL)
1365                                 goto out_nomem;
1366                         token = match_token(string,
1367                                             nfs_xprt_protocol_tokens, args);
1368                         kfree(string);
1369
1370                         mountfamily = AF_INET;
1371                         switch (token) {
1372                         case Opt_xprt_udp6:
1373                                 mountfamily = AF_INET6;
1374                         case Opt_xprt_udp:
1375                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1376                                 break;
1377                         case Opt_xprt_tcp6:
1378                                 mountfamily = AF_INET6;
1379                         case Opt_xprt_tcp:
1380                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1381                                 break;
1382                         case Opt_xprt_rdma: /* not used for side protocols */
1383                         default:
1384                                 dfprintk(MOUNT, "NFS:   unrecognized "
1385                                                 "transport protocol\n");
1386                                 return 0;
1387                         }
1388                         break;
1389                 case Opt_addr:
1390                         string = match_strdup(args);
1391                         if (string == NULL)
1392                                 goto out_nomem;
1393                         mnt->nfs_server.addrlen =
1394                                 rpc_pton(string, strlen(string),
1395                                         (struct sockaddr *)
1396                                         &mnt->nfs_server.address,
1397                                         sizeof(mnt->nfs_server.address));
1398                         kfree(string);
1399                         if (mnt->nfs_server.addrlen == 0)
1400                                 goto out_invalid_address;
1401                         break;
1402                 case Opt_clientaddr:
1403                         if (nfs_get_option_str(args, &mnt->client_address))
1404                                 goto out_nomem;
1405                         break;
1406                 case Opt_mounthost:
1407                         if (nfs_get_option_str(args,
1408                                                &mnt->mount_server.hostname))
1409                                 goto out_nomem;
1410                         break;
1411                 case Opt_mountaddr:
1412                         string = match_strdup(args);
1413                         if (string == NULL)
1414                                 goto out_nomem;
1415                         mnt->mount_server.addrlen =
1416                                 rpc_pton(string, strlen(string),
1417                                         (struct sockaddr *)
1418                                         &mnt->mount_server.address,
1419                                         sizeof(mnt->mount_server.address));
1420                         kfree(string);
1421                         if (mnt->mount_server.addrlen == 0)
1422                                 goto out_invalid_address;
1423                         break;
1424                 case Opt_lookupcache:
1425                         string = match_strdup(args);
1426                         if (string == NULL)
1427                                 goto out_nomem;
1428                         token = match_token(string,
1429                                         nfs_lookupcache_tokens, args);
1430                         kfree(string);
1431                         switch (token) {
1432                                 case Opt_lookupcache_all:
1433                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1434                                         break;
1435                                 case Opt_lookupcache_positive:
1436                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1437                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1438                                         break;
1439                                 case Opt_lookupcache_none:
1440                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1441                                         break;
1442                                 default:
1443                                         dfprintk(MOUNT, "NFS:   invalid "
1444                                                         "lookupcache argument\n");
1445                                         return 0;
1446                         };
1447                         break;
1448                 case Opt_fscache_uniq:
1449                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1450                                 goto out_nomem;
1451                         mnt->options |= NFS_OPTION_FSCACHE;
1452                         break;
1453                 case Opt_local_lock:
1454                         string = match_strdup(args);
1455                         if (string == NULL)
1456                                 goto out_nomem;
1457                         token = match_token(string, nfs_local_lock_tokens,
1458                                         args);
1459                         kfree(string);
1460                         switch (token) {
1461                         case Opt_local_lock_all:
1462                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1463                                                NFS_MOUNT_LOCAL_FCNTL);
1464                                 break;
1465                         case Opt_local_lock_flock:
1466                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1467                                 break;
1468                         case Opt_local_lock_posix:
1469                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1470                                 break;
1471                         case Opt_local_lock_none:
1472                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1473                                                 NFS_MOUNT_LOCAL_FCNTL);
1474                                 break;
1475                         default:
1476                                 dfprintk(MOUNT, "NFS:   invalid "
1477                                                 "local_lock argument\n");
1478                                 return 0;
1479                         };
1480                         break;
1481
1482                 /*
1483                  * Special options
1484                  */
1485                 case Opt_sloppy:
1486                         sloppy = 1;
1487                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1488                         break;
1489                 case Opt_userspace:
1490                 case Opt_deprecated:
1491                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1492                                         "'%s'\n", p);
1493                         break;
1494
1495                 default:
1496                         invalid_option = 1;
1497                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1498                                         "'%s'\n", p);
1499                 }
1500         }
1501
1502         if (!sloppy && invalid_option)
1503                 return 0;
1504
1505         /*
1506          * verify that any proto=/mountproto= options match the address
1507          * familiies in the addr=/mountaddr= options.
1508          */
1509         if (protofamily != AF_UNSPEC &&
1510             protofamily != mnt->nfs_server.address.ss_family)
1511                 goto out_proto_mismatch;
1512
1513         if (mountfamily != AF_UNSPEC) {
1514                 if (mnt->mount_server.addrlen) {
1515                         if (mountfamily != mnt->mount_server.address.ss_family)
1516                                 goto out_mountproto_mismatch;
1517                 } else {
1518                         if (mountfamily != mnt->nfs_server.address.ss_family)
1519                                 goto out_mountproto_mismatch;
1520                 }
1521         }
1522
1523         return 1;
1524
1525 out_mountproto_mismatch:
1526         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1527                          "option\n");
1528         return 0;
1529 out_proto_mismatch:
1530         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1531         return 0;
1532 out_invalid_address:
1533         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1534         return 0;
1535 out_invalid_value:
1536         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1537         return 0;
1538 out_nomem:
1539         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1540         return 0;
1541 out_security_failure:
1542         free_secdata(secdata);
1543         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1544         return 0;
1545 }
1546
1547 /*
1548  * Match the requested auth flavors with the list returned by
1549  * the server.  Returns zero and sets the mount's authentication
1550  * flavor on success; returns -EACCES if server does not support
1551  * the requested flavor.
1552  */
1553 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1554                              struct nfs_mount_request *request)
1555 {
1556         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1557
1558         /*
1559          * Certain releases of Linux's mountd return an empty
1560          * flavor list.  To prevent behavioral regression with
1561          * these servers (ie. rejecting mounts that used to
1562          * succeed), revert to pre-2.6.32 behavior (no checking)
1563          * if the returned flavor list is empty.
1564          */
1565         if (server_authlist_len == 0)
1566                 return 0;
1567
1568         /*
1569          * We avoid sophisticated negotiating here, as there are
1570          * plenty of cases where we can get it wrong, providing
1571          * either too little or too much security.
1572          *
1573          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1574          * flavor listed first.  However, some servers list
1575          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1576          * preferred default, in args->auth_flavors[0] if user
1577          * didn't specify sec= mount option.
1578          */
1579         for (i = 0; i < args->auth_flavor_len; i++)
1580                 for (j = 0; j < server_authlist_len; j++)
1581                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1582                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1583                                         request->auth_flavs[j]);
1584                                 args->auth_flavors[0] = request->auth_flavs[j];
1585                                 return 0;
1586                         }
1587
1588         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1589         nfs_umount(request);
1590         return -EACCES;
1591 }
1592
1593 /*
1594  * Use the remote server's MOUNT service to request the NFS file handle
1595  * corresponding to the provided path.
1596  */
1597 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1598                          struct nfs_fh *root_fh)
1599 {
1600         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1601         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1602         struct nfs_mount_request request = {
1603                 .sap            = (struct sockaddr *)
1604                                                 &args->mount_server.address,
1605                 .dirpath        = args->nfs_server.export_path,
1606                 .protocol       = args->mount_server.protocol,
1607                 .fh             = root_fh,
1608                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1609                 .auth_flav_len  = &server_authlist_len,
1610                 .auth_flavs     = server_authlist,
1611         };
1612         int status;
1613
1614         if (args->mount_server.version == 0) {
1615                 switch (args->version) {
1616                         default:
1617                                 args->mount_server.version = NFS_MNT3_VERSION;
1618                                 break;
1619                         case 2:
1620                                 args->mount_server.version = NFS_MNT_VERSION;
1621                 }
1622         }
1623         request.version = args->mount_server.version;
1624
1625         if (args->mount_server.hostname)
1626                 request.hostname = args->mount_server.hostname;
1627         else
1628                 request.hostname = args->nfs_server.hostname;
1629
1630         /*
1631          * Construct the mount server's address.
1632          */
1633         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1634                 memcpy(request.sap, &args->nfs_server.address,
1635                        args->nfs_server.addrlen);
1636                 args->mount_server.addrlen = args->nfs_server.addrlen;
1637         }
1638         request.salen = args->mount_server.addrlen;
1639         nfs_set_port(request.sap, &args->mount_server.port, 0);
1640
1641         /*
1642          * Now ask the mount server to map our export path
1643          * to a file handle.
1644          */
1645         status = nfs_mount(&request);
1646         if (status != 0) {
1647                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1648                                 request.hostname, status);
1649                 return status;
1650         }
1651
1652         /*
1653          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1654          */
1655         if (args->mount_server.version != NFS_MNT3_VERSION)
1656                 return 0;
1657         return nfs_walk_authlist(args, &request);
1658 }
1659
1660 /*
1661  * Split "dev_name" into "hostname:export_path".
1662  *
1663  * The leftmost colon demarks the split between the server's hostname
1664  * and the export path.  If the hostname starts with a left square
1665  * bracket, then it may contain colons.
1666  *
1667  * Note: caller frees hostname and export path, even on error.
1668  */
1669 static int nfs_parse_devname(const char *dev_name,
1670                              char **hostname, size_t maxnamlen,
1671                              char **export_path, size_t maxpathlen)
1672 {
1673         size_t len;
1674         char *end;
1675
1676         /* Is the host name protected with square brakcets? */
1677         if (*dev_name == '[') {
1678                 end = strchr(++dev_name, ']');
1679                 if (end == NULL || end[1] != ':')
1680                         goto out_bad_devname;
1681
1682                 len = end - dev_name;
1683                 end++;
1684         } else {
1685                 char *comma;
1686
1687                 end = strchr(dev_name, ':');
1688                 if (end == NULL)
1689                         goto out_bad_devname;
1690                 len = end - dev_name;
1691
1692                 /* kill possible hostname list: not supported */
1693                 comma = strchr(dev_name, ',');
1694                 if (comma != NULL && comma < end)
1695                         *comma = 0;
1696         }
1697
1698         if (len > maxnamlen)
1699                 goto out_hostname;
1700
1701         /* N.B. caller will free nfs_server.hostname in all cases */
1702         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1703         if (*hostname == NULL)
1704                 goto out_nomem;
1705         len = strlen(++end);
1706         if (len > maxpathlen)
1707                 goto out_path;
1708         *export_path = kstrndup(end, len, GFP_KERNEL);
1709         if (!*export_path)
1710                 goto out_nomem;
1711
1712         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1713         return 0;
1714
1715 out_bad_devname:
1716         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1717         return -EINVAL;
1718
1719 out_nomem:
1720         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1721         return -ENOMEM;
1722
1723 out_hostname:
1724         dfprintk(MOUNT, "NFS: server hostname too long\n");
1725         return -ENAMETOOLONG;
1726
1727 out_path:
1728         dfprintk(MOUNT, "NFS: export pathname too long\n");
1729         return -ENAMETOOLONG;
1730 }
1731
1732 /*
1733  * Validate the NFS2/NFS3 mount data
1734  * - fills in the mount root filehandle
1735  *
1736  * For option strings, user space handles the following behaviors:
1737  *
1738  * + DNS: mapping server host name to IP address ("addr=" option)
1739  *
1740  * + failure mode: how to behave if a mount request can't be handled
1741  *   immediately ("fg/bg" option)
1742  *
1743  * + retry: how often to retry a mount request ("retry=" option)
1744  *
1745  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1746  *   mountproto=tcp after mountproto=udp, and so on
1747  */
1748 static int nfs_validate_mount_data(void *options,
1749                                    struct nfs_parsed_mount_data *args,
1750                                    struct nfs_fh *mntfh,
1751                                    const char *dev_name)
1752 {
1753         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1754         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1755
1756         if (data == NULL)
1757                 goto out_no_data;
1758
1759         switch (data->version) {
1760         case 1:
1761                 data->namlen = 0;
1762         case 2:
1763                 data->bsize = 0;
1764         case 3:
1765                 if (data->flags & NFS_MOUNT_VER3)
1766                         goto out_no_v3;
1767                 data->root.size = NFS2_FHSIZE;
1768                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1769         case 4:
1770                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1771                         goto out_no_sec;
1772         case 5:
1773                 memset(data->context, 0, sizeof(data->context));
1774         case 6:
1775                 if (data->flags & NFS_MOUNT_VER3) {
1776                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1777                                 goto out_invalid_fh;
1778                         mntfh->size = data->root.size;
1779                         args->version = 3;
1780                 } else {
1781                         mntfh->size = NFS2_FHSIZE;
1782                         args->version = 2;
1783                 }
1784
1785
1786                 memcpy(mntfh->data, data->root.data, mntfh->size);
1787                 if (mntfh->size < sizeof(mntfh->data))
1788                         memset(mntfh->data + mntfh->size, 0,
1789                                sizeof(mntfh->data) - mntfh->size);
1790
1791                 /*
1792                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1793                  * can deal with.
1794                  */
1795                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1796                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1797                 args->rsize             = data->rsize;
1798                 args->wsize             = data->wsize;
1799                 args->timeo             = data->timeo;
1800                 args->retrans           = data->retrans;
1801                 args->acregmin          = data->acregmin;
1802                 args->acregmax          = data->acregmax;
1803                 args->acdirmin          = data->acdirmin;
1804                 args->acdirmax          = data->acdirmax;
1805
1806                 memcpy(sap, &data->addr, sizeof(data->addr));
1807                 args->nfs_server.addrlen = sizeof(data->addr);
1808                 if (!nfs_verify_server_address(sap))
1809                         goto out_no_address;
1810
1811                 if (!(data->flags & NFS_MOUNT_TCP))
1812                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1813                 /* N.B. caller will free nfs_server.hostname in all cases */
1814                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1815                 args->namlen            = data->namlen;
1816                 args->bsize             = data->bsize;
1817
1818                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1819                         args->auth_flavors[0] = data->pseudoflavor;
1820                 if (!args->nfs_server.hostname)
1821                         goto out_nomem;
1822
1823                 if (!(data->flags & NFS_MOUNT_NONLM))
1824                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1825                                          NFS_MOUNT_LOCAL_FCNTL);
1826                 else
1827                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1828                                         NFS_MOUNT_LOCAL_FCNTL);
1829                 /*
1830                  * The legacy version 6 binary mount data from userspace has a
1831                  * field used only to transport selinux information into the
1832                  * the kernel.  To continue to support that functionality we
1833                  * have a touch of selinux knowledge here in the NFS code. The
1834                  * userspace code converted context=blah to just blah so we are
1835                  * converting back to the full string selinux understands.
1836                  */
1837                 if (data->context[0]){
1838 #ifdef CONFIG_SECURITY_SELINUX
1839                         int rc;
1840                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1841                         if (!opts_str)
1842                                 return -ENOMEM;
1843                         strcpy(opts_str, "context=");
1844                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1845                         strcat(opts_str, &data->context[0]);
1846                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1847                         kfree(opts_str);
1848                         if (rc)
1849                                 return rc;
1850 #else
1851                         return -EINVAL;
1852 #endif
1853                 }
1854
1855                 break;
1856         default: {
1857                 int status;
1858
1859                 if (nfs_parse_mount_options((char *)options, args) == 0)
1860                         return -EINVAL;
1861
1862                 if (!nfs_verify_server_address(sap))
1863                         goto out_no_address;
1864
1865                 if (args->version == 4)
1866 #ifdef CONFIG_NFS_V4
1867                         return nfs4_validate_text_mount_data(options,
1868                                                              args, dev_name);
1869 #else
1870                         goto out_v4_not_compiled;
1871 #endif
1872
1873                 nfs_set_port(sap, &args->nfs_server.port, 0);
1874
1875                 nfs_set_mount_transport_protocol(args);
1876
1877                 status = nfs_parse_devname(dev_name,
1878                                            &args->nfs_server.hostname,
1879                                            PAGE_SIZE,
1880                                            &args->nfs_server.export_path,
1881                                            NFS_MAXPATHLEN);
1882                 if (!status)
1883                         status = nfs_try_mount(args, mntfh);
1884
1885                 kfree(args->nfs_server.export_path);
1886                 args->nfs_server.export_path = NULL;
1887
1888                 if (status)
1889                         return status;
1890
1891                 break;
1892                 }
1893         }
1894
1895 #ifndef CONFIG_NFS_V3
1896         if (args->version == 3)
1897                 goto out_v3_not_compiled;
1898 #endif /* !CONFIG_NFS_V3 */
1899
1900         return 0;
1901
1902 out_no_data:
1903         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1904         return -EINVAL;
1905
1906 out_no_v3:
1907         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1908                  data->version);
1909         return -EINVAL;
1910
1911 out_no_sec:
1912         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1913         return -EINVAL;
1914
1915 #ifndef CONFIG_NFS_V3
1916 out_v3_not_compiled:
1917         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1918         return -EPROTONOSUPPORT;
1919 #endif /* !CONFIG_NFS_V3 */
1920
1921 #ifndef CONFIG_NFS_V4
1922 out_v4_not_compiled:
1923         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1924         return -EPROTONOSUPPORT;
1925 #endif /* !CONFIG_NFS_V4 */
1926
1927 out_nomem:
1928         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1929         return -ENOMEM;
1930
1931 out_no_address:
1932         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1933         return -EINVAL;
1934
1935 out_invalid_fh:
1936         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1937         return -EINVAL;
1938 }
1939
1940 static int
1941 nfs_compare_remount_data(struct nfs_server *nfss,
1942                          struct nfs_parsed_mount_data *data)
1943 {
1944         if (data->flags != nfss->flags ||
1945             data->rsize != nfss->rsize ||
1946             data->wsize != nfss->wsize ||
1947             data->retrans != nfss->client->cl_timeout->to_retries ||
1948             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1949             data->acregmin != nfss->acregmin / HZ ||
1950             data->acregmax != nfss->acregmax / HZ ||
1951             data->acdirmin != nfss->acdirmin / HZ ||
1952             data->acdirmax != nfss->acdirmax / HZ ||
1953             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1954             data->nfs_server.port != nfss->port ||
1955             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1956             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1957                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1958                 return -EINVAL;
1959
1960         return 0;
1961 }
1962
1963 static int
1964 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1965 {
1966         int error;
1967         struct nfs_server *nfss = sb->s_fs_info;
1968         struct nfs_parsed_mount_data *data;
1969         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1970         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1971         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1972
1973         /*
1974          * Userspace mount programs that send binary options generally send
1975          * them populated with default values. We have no way to know which
1976          * ones were explicitly specified. Fall back to legacy behavior and
1977          * just return success.
1978          */
1979         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
1980             (nfsvers <= 3 && (!options || (options->version >= 1 &&
1981                                            options->version <= 6))))
1982                 return 0;
1983
1984         data = kzalloc(sizeof(*data), GFP_KERNEL);
1985         if (data == NULL)
1986                 return -ENOMEM;
1987
1988         /* fill out struct with values from existing mount */
1989         data->flags = nfss->flags;
1990         data->rsize = nfss->rsize;
1991         data->wsize = nfss->wsize;
1992         data->retrans = nfss->client->cl_timeout->to_retries;
1993         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1994         data->acregmin = nfss->acregmin / HZ;
1995         data->acregmax = nfss->acregmax / HZ;
1996         data->acdirmin = nfss->acdirmin / HZ;
1997         data->acdirmax = nfss->acdirmax / HZ;
1998         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1999         data->nfs_server.port = nfss->port;
2000         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2001         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2002                 data->nfs_server.addrlen);
2003
2004         /* overwrite those values with any that were specified */
2005         error = nfs_parse_mount_options((char *)options, data);
2006         if (error < 0)
2007                 goto out;
2008
2009         /*
2010          * noac is a special case. It implies -o sync, but that's not
2011          * necessarily reflected in the mtab options. do_remount_sb
2012          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2013          * remount options, so we have to explicitly reset it.
2014          */
2015         if (data->flags & NFS_MOUNT_NOAC)
2016                 *flags |= MS_SYNCHRONOUS;
2017
2018         /* compare new mount options with old ones */
2019         error = nfs_compare_remount_data(nfss, data);
2020 out:
2021         kfree(data);
2022         return error;
2023 }
2024
2025 /*
2026  * Initialise the common bits of the superblock
2027  */
2028 static inline void nfs_initialise_sb(struct super_block *sb)
2029 {
2030         struct nfs_server *server = NFS_SB(sb);
2031
2032         sb->s_magic = NFS_SUPER_MAGIC;
2033
2034         /* We probably want something more informative here */
2035         snprintf(sb->s_id, sizeof(sb->s_id),
2036                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2037
2038         if (sb->s_blocksize == 0)
2039                 sb->s_blocksize = nfs_block_bits(server->wsize,
2040                                                  &sb->s_blocksize_bits);
2041
2042         sb->s_bdi = &server->backing_dev_info;
2043
2044         nfs_super_set_maxbytes(sb, server->maxfilesize);
2045 }
2046
2047 /*
2048  * Finish setting up an NFS2/3 superblock
2049  */
2050 static void nfs_fill_super(struct super_block *sb,
2051                            struct nfs_parsed_mount_data *data)
2052 {
2053         struct nfs_server *server = NFS_SB(sb);
2054
2055         sb->s_blocksize_bits = 0;
2056         sb->s_blocksize = 0;
2057         if (data->bsize)
2058                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2059
2060         if (server->nfs_client->rpc_ops->version == 3) {
2061                 /* The VFS shouldn't apply the umask to mode bits. We will do
2062                  * so ourselves when necessary.
2063                  */
2064                 sb->s_flags |= MS_POSIXACL;
2065                 sb->s_time_gran = 1;
2066         }
2067
2068         sb->s_op = &nfs_sops;
2069         nfs_initialise_sb(sb);
2070 }
2071
2072 /*
2073  * Finish setting up a cloned NFS2/3 superblock
2074  */
2075 static void nfs_clone_super(struct super_block *sb,
2076                             const struct super_block *old_sb)
2077 {
2078         struct nfs_server *server = NFS_SB(sb);
2079
2080         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2081         sb->s_blocksize = old_sb->s_blocksize;
2082         sb->s_maxbytes = old_sb->s_maxbytes;
2083
2084         if (server->nfs_client->rpc_ops->version == 3) {
2085                 /* The VFS shouldn't apply the umask to mode bits. We will do
2086                  * so ourselves when necessary.
2087                  */
2088                 sb->s_flags |= MS_POSIXACL;
2089                 sb->s_time_gran = 1;
2090         }
2091
2092         sb->s_op = old_sb->s_op;
2093         nfs_initialise_sb(sb);
2094 }
2095
2096 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2097 {
2098         const struct nfs_server *a = s->s_fs_info;
2099         const struct rpc_clnt *clnt_a = a->client;
2100         const struct rpc_clnt *clnt_b = b->client;
2101
2102         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2103                 goto Ebusy;
2104         if (a->nfs_client != b->nfs_client)
2105                 goto Ebusy;
2106         if (a->flags != b->flags)
2107                 goto Ebusy;
2108         if (a->wsize != b->wsize)
2109                 goto Ebusy;
2110         if (a->rsize != b->rsize)
2111                 goto Ebusy;
2112         if (a->acregmin != b->acregmin)
2113                 goto Ebusy;
2114         if (a->acregmax != b->acregmax)
2115                 goto Ebusy;
2116         if (a->acdirmin != b->acdirmin)
2117                 goto Ebusy;
2118         if (a->acdirmax != b->acdirmax)
2119                 goto Ebusy;
2120         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2121                 goto Ebusy;
2122         return 1;
2123 Ebusy:
2124         return 0;
2125 }
2126
2127 struct nfs_sb_mountdata {
2128         struct nfs_server *server;
2129         int mntflags;
2130 };
2131
2132 static int nfs_set_super(struct super_block *s, void *data)
2133 {
2134         struct nfs_sb_mountdata *sb_mntdata = data;
2135         struct nfs_server *server = sb_mntdata->server;
2136         int ret;
2137
2138         s->s_flags = sb_mntdata->mntflags;
2139         s->s_fs_info = server;
2140         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2141         ret = set_anon_super(s, server);
2142         if (ret == 0)
2143                 server->s_dev = s->s_dev;
2144         return ret;
2145 }
2146
2147 static int nfs_compare_super_address(struct nfs_server *server1,
2148                                      struct nfs_server *server2)
2149 {
2150         struct sockaddr *sap1, *sap2;
2151
2152         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2153         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2154
2155         if (sap1->sa_family != sap2->sa_family)
2156                 return 0;
2157
2158         switch (sap1->sa_family) {
2159         case AF_INET: {
2160                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2161                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2162                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2163                         return 0;
2164                 if (sin1->sin_port != sin2->sin_port)
2165                         return 0;
2166                 break;
2167         }
2168         case AF_INET6: {
2169                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2170                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2171                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2172                         return 0;
2173                 if (sin1->sin6_port != sin2->sin6_port)
2174                         return 0;
2175                 break;
2176         }
2177         default:
2178                 return 0;
2179         }
2180
2181         return 1;
2182 }
2183
2184 static int nfs_compare_super(struct super_block *sb, void *data)
2185 {
2186         struct nfs_sb_mountdata *sb_mntdata = data;
2187         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2188         int mntflags = sb_mntdata->mntflags;
2189
2190         if (!nfs_compare_super_address(old, server))
2191                 return 0;
2192         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2193         if (old->flags & NFS_MOUNT_UNSHARED)
2194                 return 0;
2195         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2196                 return 0;
2197         return nfs_compare_mount_options(sb, server, mntflags);
2198 }
2199
2200 static int nfs_bdi_register(struct nfs_server *server)
2201 {
2202         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2203 }
2204
2205 static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2206         int flags, const char *dev_name, void *raw_data)
2207 {
2208         struct nfs_server *server = NULL;
2209         struct super_block *s;
2210         struct nfs_parsed_mount_data *data;
2211         struct nfs_fh *mntfh;
2212         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2213         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2214         struct nfs_sb_mountdata sb_mntdata = {
2215                 .mntflags = flags,
2216         };
2217         int error;
2218
2219         data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
2220         mntfh = nfs_alloc_fhandle();
2221         if (data == NULL || mntfh == NULL)
2222                 goto out_free_fh;
2223
2224         security_init_mnt_opts(&data->lsm_opts);
2225
2226         /* Validate the mount data */
2227         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2228         if (error < 0) {
2229                 mntroot = ERR_PTR(error);
2230                 goto out;
2231         }
2232
2233 #ifdef CONFIG_NFS_V4
2234         if (data->version == 4) {
2235                 mntroot = nfs4_try_mount(flags, dev_name, data);
2236                 kfree(data->client_address);
2237                 kfree(data->nfs_server.export_path);
2238                 goto out;
2239         }
2240 #endif  /* CONFIG_NFS_V4 */
2241
2242         /* Get a volume representation */
2243         server = nfs_create_server(data, mntfh);
2244         if (IS_ERR(server)) {
2245                 mntroot = ERR_CAST(server);
2246                 goto out;
2247         }
2248         sb_mntdata.server = server;
2249
2250         if (server->flags & NFS_MOUNT_UNSHARED)
2251                 compare_super = NULL;
2252
2253         /* -o noac implies -o sync */
2254         if (server->flags & NFS_MOUNT_NOAC)
2255                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2256
2257         /* Get a superblock - note that we may end up sharing one that already exists */
2258         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2259         if (IS_ERR(s)) {
2260                 mntroot = ERR_CAST(s);
2261                 goto out_err_nosb;
2262         }
2263
2264         if (s->s_fs_info != server) {
2265                 nfs_free_server(server);
2266                 server = NULL;
2267         } else {
2268                 error = nfs_bdi_register(server);
2269                 if (error) {
2270                         mntroot = ERR_PTR(error);
2271                         goto error_splat_bdi;
2272                 }
2273         }
2274
2275         if (!s->s_root) {
2276                 /* initial superblock/root creation */
2277                 nfs_fill_super(s, data);
2278                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2279         }
2280
2281         mntroot = nfs_get_root(s, mntfh, dev_name);
2282         if (IS_ERR(mntroot))
2283                 goto error_splat_super;
2284
2285         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2286         if (error)
2287                 goto error_splat_root;
2288
2289         s->s_flags |= MS_ACTIVE;
2290
2291 out:
2292         kfree(data->nfs_server.hostname);
2293         kfree(data->mount_server.hostname);
2294         kfree(data->fscache_uniq);
2295         security_free_mnt_opts(&data->lsm_opts);
2296 out_free_fh:
2297         nfs_free_fhandle(mntfh);
2298         kfree(data);
2299         return mntroot;
2300
2301 out_err_nosb:
2302         nfs_free_server(server);
2303         goto out;
2304
2305 error_splat_root:
2306         dput(mntroot);
2307         mntroot = ERR_PTR(error);
2308 error_splat_super:
2309         if (server && !s->s_root)
2310                 bdi_unregister(&server->backing_dev_info);
2311 error_splat_bdi:
2312         deactivate_locked_super(s);
2313         goto out;
2314 }
2315
2316 /*
2317  * Ensure that we unregister the bdi before kill_anon_super
2318  * releases the device name
2319  */
2320 static void nfs_put_super(struct super_block *s)
2321 {
2322         struct nfs_server *server = NFS_SB(s);
2323
2324         bdi_unregister(&server->backing_dev_info);
2325 }
2326
2327 /*
2328  * Destroy an NFS2/3 superblock
2329  */
2330 static void nfs_kill_super(struct super_block *s)
2331 {
2332         struct nfs_server *server = NFS_SB(s);
2333
2334         kill_anon_super(s);
2335         nfs_fscache_release_super_cookie(s);
2336         nfs_free_server(server);
2337 }
2338
2339 /*
2340  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2341  */
2342 static struct dentry *
2343 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2344                 const char *dev_name, void *raw_data)
2345 {
2346         struct nfs_clone_mount *data = raw_data;
2347         struct super_block *s;
2348         struct nfs_server *server;
2349         struct dentry *mntroot;
2350         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2351         struct nfs_sb_mountdata sb_mntdata = {
2352                 .mntflags = flags,
2353         };
2354         int error;
2355
2356         dprintk("--> nfs_xdev_mount()\n");
2357
2358         /* create a new volume representation */
2359         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2360         if (IS_ERR(server)) {
2361                 error = PTR_ERR(server);
2362                 goto out_err_noserver;
2363         }
2364         sb_mntdata.server = server;
2365
2366         if (server->flags & NFS_MOUNT_UNSHARED)
2367                 compare_super = NULL;
2368
2369         /* -o noac implies -o sync */
2370         if (server->flags & NFS_MOUNT_NOAC)
2371                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2372
2373         /* Get a superblock - note that we may end up sharing one that already exists */
2374         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2375         if (IS_ERR(s)) {
2376                 error = PTR_ERR(s);
2377                 goto out_err_nosb;
2378         }
2379
2380         if (s->s_fs_info != server) {
2381                 nfs_free_server(server);
2382                 server = NULL;
2383         } else {
2384                 error = nfs_bdi_register(server);
2385                 if (error)
2386                         goto error_splat_bdi;
2387         }
2388
2389         if (!s->s_root) {
2390                 /* initial superblock/root creation */
2391                 nfs_clone_super(s, data->sb);
2392                 nfs_fscache_get_super_cookie(s, NULL, data);
2393         }
2394
2395         mntroot = nfs_get_root(s, data->fh, dev_name);
2396         if (IS_ERR(mntroot)) {
2397                 error = PTR_ERR(mntroot);
2398                 goto error_splat_super;
2399         }
2400         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2401                 dput(mntroot);
2402                 error = -ESTALE;
2403                 goto error_splat_super;
2404         }
2405
2406         s->s_flags |= MS_ACTIVE;
2407
2408         /* clone any lsm security options from the parent to the new sb */
2409         security_sb_clone_mnt_opts(data->sb, s);
2410
2411         dprintk("<-- nfs_xdev_mount() = 0\n");
2412         return mntroot;
2413
2414 out_err_nosb:
2415         nfs_free_server(server);
2416 out_err_noserver:
2417         dprintk("<-- nfs_xdev_mount() = %d [error]\n", error);
2418         return ERR_PTR(error);
2419
2420 error_splat_super:
2421         if (server && !s->s_root)
2422                 bdi_unregister(&server->backing_dev_info);
2423 error_splat_bdi:
2424         deactivate_locked_super(s);
2425         dprintk("<-- nfs_xdev_mount() = %d [splat]\n", error);
2426         return ERR_PTR(error);
2427 }
2428
2429 #ifdef CONFIG_NFS_V4
2430
2431 /*
2432  * Finish setting up a cloned NFS4 superblock
2433  */
2434 static void nfs4_clone_super(struct super_block *sb,
2435                             const struct super_block *old_sb)
2436 {
2437         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2438         sb->s_blocksize = old_sb->s_blocksize;
2439         sb->s_maxbytes = old_sb->s_maxbytes;
2440         sb->s_time_gran = 1;
2441         sb->s_op = old_sb->s_op;
2442         /*
2443          * The VFS shouldn't apply the umask to mode bits. We will do
2444          * so ourselves when necessary.
2445          */
2446         sb->s_flags  |= MS_POSIXACL;
2447         sb->s_xattr  = old_sb->s_xattr;
2448         nfs_initialise_sb(sb);
2449 }
2450
2451 /*
2452  * Set up an NFS4 superblock
2453  */
2454 static void nfs4_fill_super(struct super_block *sb)
2455 {
2456         sb->s_time_gran = 1;
2457         sb->s_op = &nfs4_sops;
2458         /*
2459          * The VFS shouldn't apply the umask to mode bits. We will do
2460          * so ourselves when necessary.
2461          */
2462         sb->s_flags  |= MS_POSIXACL;
2463         sb->s_xattr = nfs4_xattr_handlers;
2464         nfs_initialise_sb(sb);
2465 }
2466
2467 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2468 {
2469         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2470                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2471 }
2472
2473 static int nfs4_validate_text_mount_data(void *options,
2474                                          struct nfs_parsed_mount_data *args,
2475                                          const char *dev_name)
2476 {
2477         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2478
2479         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2480
2481         nfs_validate_transport_protocol(args);
2482
2483         nfs4_validate_mount_flags(args);
2484
2485         if (args->version != 4) {
2486                 dfprintk(MOUNT,
2487                          "NFS4: Illegal mount version\n");
2488                 return -EINVAL;
2489         }
2490
2491         if (args->auth_flavor_len > 1) {
2492                 dfprintk(MOUNT,
2493                          "NFS4: Too many RPC auth flavours specified\n");
2494                 return -EINVAL;
2495         }
2496
2497         if (args->client_address == NULL) {
2498                 dfprintk(MOUNT,
2499                          "NFS4: mount program didn't pass callback address\n");
2500                 return -EINVAL;
2501         }
2502
2503         return nfs_parse_devname(dev_name,
2504                                    &args->nfs_server.hostname,
2505                                    NFS4_MAXNAMLEN,
2506                                    &args->nfs_server.export_path,
2507                                    NFS4_MAXPATHLEN);
2508 }
2509
2510 /*
2511  * Validate NFSv4 mount options
2512  */
2513 static int nfs4_validate_mount_data(void *options,
2514                                     struct nfs_parsed_mount_data *args,
2515                                     const char *dev_name)
2516 {
2517         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2518         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2519         char *c;
2520
2521         if (data == NULL)
2522                 goto out_no_data;
2523
2524         switch (data->version) {
2525         case 1:
2526                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2527                         goto out_no_address;
2528                 if (data->host_addrlen == 0)
2529                         goto out_no_address;
2530                 args->nfs_server.addrlen = data->host_addrlen;
2531                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2532                         return -EFAULT;
2533                 if (!nfs_verify_server_address(sap))
2534                         goto out_no_address;
2535
2536                 if (data->auth_flavourlen) {
2537                         if (data->auth_flavourlen > 1)
2538                                 goto out_inval_auth;
2539                         if (copy_from_user(&args->auth_flavors[0],
2540                                            data->auth_flavours,
2541                                            sizeof(args->auth_flavors[0])))
2542                                 return -EFAULT;
2543                 }
2544
2545                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2546                 if (IS_ERR(c))
2547                         return PTR_ERR(c);
2548                 args->nfs_server.hostname = c;
2549
2550                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2551                 if (IS_ERR(c))
2552                         return PTR_ERR(c);
2553                 args->nfs_server.export_path = c;
2554                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2555
2556                 c = strndup_user(data->client_addr.data, 16);
2557                 if (IS_ERR(c))
2558                         return PTR_ERR(c);
2559                 args->client_address = c;
2560
2561                 /*
2562                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2563                  * can deal with.
2564                  */
2565
2566                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2567                 args->rsize     = data->rsize;
2568                 args->wsize     = data->wsize;
2569                 args->timeo     = data->timeo;
2570                 args->retrans   = data->retrans;
2571                 args->acregmin  = data->acregmin;
2572                 args->acregmax  = data->acregmax;
2573                 args->acdirmin  = data->acdirmin;
2574                 args->acdirmax  = data->acdirmax;
2575                 args->nfs_server.protocol = data->proto;
2576                 nfs_validate_transport_protocol(args);
2577
2578                 break;
2579         default:
2580                 if (nfs_parse_mount_options((char *)options, args) == 0)
2581                         return -EINVAL;
2582
2583                 if (!nfs_verify_server_address(sap))
2584                         return -EINVAL;
2585
2586                 return nfs4_validate_text_mount_data(options, args, dev_name);
2587         }
2588
2589         return 0;
2590
2591 out_no_data:
2592         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2593         return -EINVAL;
2594
2595 out_inval_auth:
2596         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2597                  data->auth_flavourlen);
2598         return -EINVAL;
2599
2600 out_no_address:
2601         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2602         return -EINVAL;
2603 }
2604
2605 /*
2606  * Get the superblock for the NFS4 root partition
2607  */
2608 static struct dentry *
2609 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
2610                   const char *dev_name, void *raw_data)
2611 {
2612         struct nfs_parsed_mount_data *data = raw_data;
2613         struct super_block *s;
2614         struct nfs_server *server;
2615         struct nfs_fh *mntfh;
2616         struct dentry *mntroot;
2617         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2618         struct nfs_sb_mountdata sb_mntdata = {
2619                 .mntflags = flags,
2620         };
2621         int error = -ENOMEM;
2622
2623         mntfh = nfs_alloc_fhandle();
2624         if (data == NULL || mntfh == NULL)
2625                 goto out_free_fh;
2626
2627         security_init_mnt_opts(&data->lsm_opts);
2628
2629         /* Get a volume representation */
2630         server = nfs4_create_server(data, mntfh);
2631         if (IS_ERR(server)) {
2632                 error = PTR_ERR(server);
2633                 goto out;
2634         }
2635         sb_mntdata.server = server;
2636
2637         if (server->flags & NFS4_MOUNT_UNSHARED)
2638                 compare_super = NULL;
2639
2640         /* -o noac implies -o sync */
2641         if (server->flags & NFS_MOUNT_NOAC)
2642                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2643
2644         /* Get a superblock - note that we may end up sharing one that already exists */
2645         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2646         if (IS_ERR(s)) {
2647                 error = PTR_ERR(s);
2648                 goto out_free;
2649         }
2650
2651         if (s->s_fs_info != server) {
2652                 nfs_free_server(server);
2653                 server = NULL;
2654         } else {
2655                 error = nfs_bdi_register(server);
2656                 if (error)
2657                         goto error_splat_bdi;
2658         }
2659
2660         if (!s->s_root) {
2661                 /* initial superblock/root creation */
2662                 nfs4_fill_super(s);
2663                 nfs_fscache_get_super_cookie(
2664                         s, data ? data->fscache_uniq : NULL, NULL);
2665         }
2666
2667         mntroot = nfs4_get_root(s, mntfh, dev_name);
2668         if (IS_ERR(mntroot)) {
2669                 error = PTR_ERR(mntroot);
2670                 goto error_splat_super;
2671         }
2672
2673         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2674         if (error)
2675                 goto error_splat_root;
2676
2677         s->s_flags |= MS_ACTIVE;
2678
2679         security_free_mnt_opts(&data->lsm_opts);
2680         nfs_free_fhandle(mntfh);
2681         return mntroot;
2682
2683 out:
2684         security_free_mnt_opts(&data->lsm_opts);
2685 out_free_fh:
2686         nfs_free_fhandle(mntfh);
2687         return ERR_PTR(error);
2688
2689 out_free:
2690         nfs_free_server(server);
2691         goto out;
2692
2693 error_splat_root:
2694         dput(mntroot);
2695 error_splat_super:
2696         if (server && !s->s_root)
2697                 bdi_unregister(&server->backing_dev_info);
2698 error_splat_bdi:
2699         deactivate_locked_super(s);
2700         goto out;
2701 }
2702
2703 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2704                 int flags, void *data, const char *hostname)
2705 {
2706         struct vfsmount *root_mnt;
2707         char *root_devname;
2708         size_t len;
2709
2710         len = strlen(hostname) + 3;
2711         root_devname = kmalloc(len, GFP_KERNEL);
2712         if (root_devname == NULL)
2713                 return ERR_PTR(-ENOMEM);
2714         snprintf(root_devname, len, "%s:/", hostname);
2715         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2716         kfree(root_devname);
2717         return root_mnt;
2718 }
2719
2720 struct nfs_referral_count {
2721         struct list_head list;
2722         const struct task_struct *task;
2723         unsigned int referral_count;
2724 };
2725
2726 static LIST_HEAD(nfs_referral_count_list);
2727 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2728
2729 static struct nfs_referral_count *nfs_find_referral_count(void)
2730 {
2731         struct nfs_referral_count *p;
2732
2733         list_for_each_entry(p, &nfs_referral_count_list, list) {
2734                 if (p->task == current)
2735                         return p;
2736         }
2737         return NULL;
2738 }
2739
2740 #define NFS_MAX_NESTED_REFERRALS 2
2741
2742 static int nfs_referral_loop_protect(void)
2743 {
2744         struct nfs_referral_count *p, *new;
2745         int ret = -ENOMEM;
2746
2747         new = kmalloc(sizeof(*new), GFP_KERNEL);
2748         if (!new)
2749                 goto out;
2750         new->task = current;
2751         new->referral_count = 1;
2752
2753         ret = 0;
2754         spin_lock(&nfs_referral_count_list_lock);
2755         p = nfs_find_referral_count();
2756         if (p != NULL) {
2757                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2758                         ret = -ELOOP;
2759                 else
2760                         p->referral_count++;
2761         } else {
2762                 list_add(&new->list, &nfs_referral_count_list);
2763                 new = NULL;
2764         }
2765         spin_unlock(&nfs_referral_count_list_lock);
2766         kfree(new);
2767 out:
2768         return ret;
2769 }
2770
2771 static void nfs_referral_loop_unprotect(void)
2772 {
2773         struct nfs_referral_count *p;
2774
2775         spin_lock(&nfs_referral_count_list_lock);
2776         p = nfs_find_referral_count();
2777         p->referral_count--;
2778         if (p->referral_count == 0)
2779                 list_del(&p->list);
2780         else
2781                 p = NULL;
2782         spin_unlock(&nfs_referral_count_list_lock);
2783         kfree(p);
2784 }
2785
2786 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
2787                 const char *export_path)
2788 {
2789         struct dentry *dentry;
2790         int err;
2791
2792         if (IS_ERR(root_mnt))
2793                 return ERR_CAST(root_mnt);
2794
2795         err = nfs_referral_loop_protect();
2796         if (err) {
2797                 mntput(root_mnt);
2798                 return ERR_PTR(err);
2799         }
2800
2801         dentry = mount_subtree(root_mnt, export_path);
2802         nfs_referral_loop_unprotect();
2803
2804         return dentry;
2805 }
2806
2807 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
2808                          struct nfs_parsed_mount_data *data)
2809 {
2810         char *export_path;
2811         struct vfsmount *root_mnt;
2812         struct dentry *res;
2813
2814         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2815
2816         export_path = data->nfs_server.export_path;
2817         data->nfs_server.export_path = "/";
2818         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2819                         data->nfs_server.hostname);
2820         data->nfs_server.export_path = export_path;
2821
2822         res = nfs_follow_remote_path(root_mnt, export_path);
2823
2824         dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
2825                         IS_ERR(res) ? PTR_ERR(res) : 0,
2826                         IS_ERR(res) ? " [error]" : "");
2827         return res;
2828 }
2829
2830 /*
2831  * Get the superblock for an NFS4 mountpoint
2832  */
2833 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
2834         int flags, const char *dev_name, void *raw_data)
2835 {
2836         struct nfs_parsed_mount_data *data;
2837         int error = -ENOMEM;
2838         struct dentry *res = ERR_PTR(-ENOMEM);
2839
2840         data = nfs_alloc_parsed_mount_data(4);
2841         if (data == NULL)
2842                 goto out_free_data;
2843
2844         /* Validate the mount data */
2845         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2846         if (error < 0) {
2847                 res = ERR_PTR(error);
2848                 goto out;
2849         }
2850
2851         res = nfs4_try_mount(flags, dev_name, data);
2852         if (IS_ERR(res))
2853                 error = PTR_ERR(res);
2854
2855 out:
2856         kfree(data->client_address);
2857         kfree(data->nfs_server.export_path);
2858         kfree(data->nfs_server.hostname);
2859         kfree(data->fscache_uniq);
2860 out_free_data:
2861         kfree(data);
2862         dprintk("<-- nfs4_mount() = %d%s\n", error,
2863                         error != 0 ? " [error]" : "");
2864         return res;
2865 }
2866
2867 static void nfs4_kill_super(struct super_block *sb)
2868 {
2869         struct nfs_server *server = NFS_SB(sb);
2870
2871         dprintk("--> %s\n", __func__);
2872         nfs_super_return_all_delegations(sb);
2873         kill_anon_super(sb);
2874         nfs_fscache_release_super_cookie(sb);
2875         nfs_free_server(server);
2876         dprintk("<-- %s\n", __func__);
2877 }
2878
2879 /*
2880  * Clone an NFS4 server record on xdev traversal (FSID-change)
2881  */
2882 static struct dentry *
2883 nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
2884                  const char *dev_name, void *raw_data)
2885 {
2886         struct nfs_clone_mount *data = raw_data;
2887         struct super_block *s;
2888         struct nfs_server *server;
2889         struct dentry *mntroot;
2890         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2891         struct nfs_sb_mountdata sb_mntdata = {
2892                 .mntflags = flags,
2893         };
2894         int error;
2895
2896         dprintk("--> nfs4_xdev_mount()\n");
2897
2898         /* create a new volume representation */
2899         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2900         if (IS_ERR(server)) {
2901                 error = PTR_ERR(server);
2902                 goto out_err_noserver;
2903         }
2904         sb_mntdata.server = server;
2905
2906         if (server->flags & NFS4_MOUNT_UNSHARED)
2907                 compare_super = NULL;
2908
2909         /* -o noac implies -o sync */
2910         if (server->flags & NFS_MOUNT_NOAC)
2911                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2912
2913         /* Get a superblock - note that we may end up sharing one that already exists */
2914         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2915         if (IS_ERR(s)) {
2916                 error = PTR_ERR(s);
2917                 goto out_err_nosb;
2918         }
2919
2920         if (s->s_fs_info != server) {
2921                 nfs_free_server(server);
2922                 server = NULL;
2923         } else {
2924                 error = nfs_bdi_register(server);
2925                 if (error)
2926                         goto error_splat_bdi;
2927         }
2928
2929         if (!s->s_root) {
2930                 /* initial superblock/root creation */
2931                 nfs4_clone_super(s, data->sb);
2932                 nfs_fscache_get_super_cookie(s, NULL, data);
2933         }
2934
2935         mntroot = nfs4_get_root(s, data->fh, dev_name);
2936         if (IS_ERR(mntroot)) {
2937                 error = PTR_ERR(mntroot);
2938                 goto error_splat_super;
2939         }
2940         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2941                 dput(mntroot);
2942                 error = -ESTALE;
2943                 goto error_splat_super;
2944         }
2945
2946         s->s_flags |= MS_ACTIVE;
2947
2948         security_sb_clone_mnt_opts(data->sb, s);
2949
2950         dprintk("<-- nfs4_xdev_mount() = 0\n");
2951         return mntroot;
2952
2953 out_err_nosb:
2954         nfs_free_server(server);
2955 out_err_noserver:
2956         dprintk("<-- nfs4_xdev_mount() = %d [error]\n", error);
2957         return ERR_PTR(error);
2958
2959 error_splat_super:
2960         if (server && !s->s_root)
2961                 bdi_unregister(&server->backing_dev_info);
2962 error_splat_bdi:
2963         deactivate_locked_super(s);
2964         dprintk("<-- nfs4_xdev_mount() = %d [splat]\n", error);
2965         return ERR_PTR(error);
2966 }
2967
2968 static struct dentry *
2969 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
2970                            const char *dev_name, void *raw_data)
2971 {
2972         struct nfs_clone_mount *data = raw_data;
2973         struct super_block *s;
2974         struct nfs_server *server;
2975         struct dentry *mntroot;
2976         struct nfs_fh *mntfh;
2977         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2978         struct nfs_sb_mountdata sb_mntdata = {
2979                 .mntflags = flags,
2980         };
2981         int error = -ENOMEM;
2982
2983         dprintk("--> nfs4_referral_get_sb()\n");
2984
2985         mntfh = nfs_alloc_fhandle();
2986         if (mntfh == NULL)
2987                 goto out_err_nofh;
2988
2989         /* create a new volume representation */
2990         server = nfs4_create_referral_server(data, mntfh);
2991         if (IS_ERR(server)) {
2992                 error = PTR_ERR(server);
2993                 goto out_err_noserver;
2994         }
2995         sb_mntdata.server = server;
2996
2997         if (server->flags & NFS4_MOUNT_UNSHARED)
2998                 compare_super = NULL;
2999
3000         /* -o noac implies -o sync */
3001         if (server->flags & NFS_MOUNT_NOAC)
3002                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
3003
3004         /* Get a superblock - note that we may end up sharing one that already exists */
3005         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
3006         if (IS_ERR(s)) {
3007                 error = PTR_ERR(s);
3008                 goto out_err_nosb;
3009         }
3010
3011         if (s->s_fs_info != server) {
3012                 nfs_free_server(server);
3013                 server = NULL;
3014         } else {
3015                 error = nfs_bdi_register(server);
3016                 if (error)
3017                         goto error_splat_bdi;
3018         }
3019
3020         if (!s->s_root) {
3021                 /* initial superblock/root creation */
3022                 nfs4_fill_super(s);
3023                 nfs_fscache_get_super_cookie(s, NULL, data);
3024         }
3025
3026         mntroot = nfs4_get_root(s, mntfh, dev_name);
3027         if (IS_ERR(mntroot)) {
3028                 error = PTR_ERR(mntroot);
3029                 goto error_splat_super;
3030         }
3031         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3032                 dput(mntroot);
3033                 error = -ESTALE;
3034                 goto error_splat_super;
3035         }
3036
3037         s->s_flags |= MS_ACTIVE;
3038
3039         security_sb_clone_mnt_opts(data->sb, s);
3040
3041         nfs_free_fhandle(mntfh);
3042         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3043         return mntroot;
3044
3045 out_err_nosb:
3046         nfs_free_server(server);
3047 out_err_noserver:
3048         nfs_free_fhandle(mntfh);
3049 out_err_nofh:
3050         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3051         return ERR_PTR(error);
3052
3053 error_splat_super:
3054         if (server && !s->s_root)
3055                 bdi_unregister(&server->backing_dev_info);
3056 error_splat_bdi:
3057         deactivate_locked_super(s);
3058         nfs_free_fhandle(mntfh);
3059         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3060         return ERR_PTR(error);
3061 }
3062
3063 /*
3064  * Create an NFS4 server record on referral traversal
3065  */
3066 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
3067                 int flags, const char *dev_name, void *raw_data)
3068 {
3069         struct nfs_clone_mount *data = raw_data;
3070         char *export_path;
3071         struct vfsmount *root_mnt;
3072         struct dentry *res;
3073
3074         dprintk("--> nfs4_referral_mount()\n");
3075
3076         export_path = data->mnt_path;
3077         data->mnt_path = "/";
3078
3079         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3080                         flags, data, data->hostname);
3081         data->mnt_path = export_path;
3082
3083         res = nfs_follow_remote_path(root_mnt, export_path);
3084         dprintk("<-- nfs4_referral_mount() = %ld%s\n",
3085                         IS_ERR(res) ? PTR_ERR(res) : 0,
3086                         IS_ERR(res) ? " [error]" : "");
3087         return res;
3088 }
3089
3090 #endif /* CONFIG_NFS_V4 */