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

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/seq_file.h>
  43 #include <linux/mount.h>
  44 #include <linux/namei.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56
  57 #include <asm/system.h>
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "pnfs.h"
  67
  68 #define NFSDBG_FACILITY         NFSDBG_VFS
  69
  70 #ifdef CONFIG_NFS_V3
  71 #define NFS_DEFAULT_VERSION 3
  72 #else
  73 #define NFS_DEFAULT_VERSION 2
  74 #endif
  75
  76 enum {
  77         /* Mount options that take no arguments */
  78         Opt_soft, Opt_hard,
  79         Opt_posix, Opt_noposix,
  80         Opt_cto, Opt_nocto,
  81         Opt_ac, Opt_noac,
  82         Opt_lock, Opt_nolock,
  83         Opt_v2, Opt_v3, Opt_v4, Opt_v4_0, Opt_v4_1,
  84         Opt_udp, Opt_tcp, Opt_rdma,
  85         Opt_acl, Opt_noacl,
  86         Opt_rdirplus, Opt_nordirplus,
  87         Opt_sharecache, Opt_nosharecache,
  88         Opt_resvport, Opt_noresvport,
  89         Opt_fscache, Opt_nofscache,
  90
  91         /* Mount options that take integer arguments */
  92         Opt_port,
  93         Opt_rsize, Opt_wsize, Opt_bsize,
  94         Opt_timeo, Opt_retrans,
  95         Opt_acregmin, Opt_acregmax,
  96         Opt_acdirmin, Opt_acdirmax,
  97         Opt_actimeo,
  98         Opt_namelen,
  99         Opt_mountport,
 100         Opt_mountvers,
 101         Opt_nfsvers,
 102         Opt_minorversion,
 103
 104         /* Mount options that take string arguments */
 105         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 106         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 107         Opt_lookupcache,
 108         Opt_fscache_uniq,
 109         Opt_local_lock,
 110
 111         /* Special mount options */
 112         Opt_userspace, Opt_deprecated, Opt_sloppy,
 113
 114         Opt_err
 115 };
 116
 117 static const match_table_t nfs_mount_option_tokens = {
 118         { Opt_userspace, "bg" },
 119         { Opt_userspace, "fg" },
 120         { Opt_userspace, "retry=%s" },
 121
 122         { Opt_sloppy, "sloppy" },
 123
 124         { Opt_soft, "soft" },
 125         { Opt_hard, "hard" },
 126         { Opt_deprecated, "intr" },
 127         { Opt_deprecated, "nointr" },
 128         { Opt_posix, "posix" },
 129         { Opt_noposix, "noposix" },
 130         { Opt_cto, "cto" },
 131         { Opt_nocto, "nocto" },
 132         { Opt_ac, "ac" },
 133         { Opt_noac, "noac" },
 134         { Opt_lock, "lock" },
 135         { Opt_nolock, "nolock" },
 136         { Opt_v2, "v2" },
 137         { Opt_v3, "v3" },
 138         { Opt_v4, "v4" },
 139         { Opt_v4_0, "v4.0" },
 140         { Opt_v4_1, "v4.1" },
 141         { Opt_udp, "udp" },
 142         { Opt_tcp, "tcp" },
 143         { Opt_rdma, "rdma" },
 144         { Opt_acl, "acl" },
 145         { Opt_noacl, "noacl" },
 146         { Opt_rdirplus, "rdirplus" },
 147         { Opt_nordirplus, "nordirplus" },
 148         { Opt_sharecache, "sharecache" },
 149         { Opt_nosharecache, "nosharecache" },
 150         { Opt_resvport, "resvport" },
 151         { Opt_noresvport, "noresvport" },
 152         { Opt_fscache, "fsc" },
 153         { Opt_nofscache, "nofsc" },
 154
 155         { Opt_port, "port=%s" },
 156         { Opt_rsize, "rsize=%s" },
 157         { Opt_wsize, "wsize=%s" },
 158         { Opt_bsize, "bsize=%s" },
 159         { Opt_timeo, "timeo=%s" },
 160         { Opt_retrans, "retrans=%s" },
 161         { Opt_acregmin, "acregmin=%s" },
 162         { Opt_acregmax, "acregmax=%s" },
 163         { Opt_acdirmin, "acdirmin=%s" },
 164         { Opt_acdirmax, "acdirmax=%s" },
 165         { Opt_actimeo, "actimeo=%s" },
 166         { Opt_namelen, "namlen=%s" },
 167         { Opt_mountport, "mountport=%s" },
 168         { Opt_mountvers, "mountvers=%s" },
 169         { Opt_nfsvers, "nfsvers=%s" },
 170         { Opt_nfsvers, "vers=%s" },
 171         { Opt_minorversion, "minorversion=%s" },
 172
 173         { Opt_sec, "sec=%s" },
 174         { Opt_proto, "proto=%s" },
 175         { Opt_mountproto, "mountproto=%s" },
 176         { Opt_addr, "addr=%s" },
 177         { Opt_clientaddr, "clientaddr=%s" },
 178         { Opt_mounthost, "mounthost=%s" },
 179         { Opt_mountaddr, "mountaddr=%s" },
 180
 181         { Opt_lookupcache, "lookupcache=%s" },
 182         { Opt_fscache_uniq, "fsc=%s" },
 183         { Opt_local_lock, "local_lock=%s" },
 184
 185         { Opt_err, NULL }
 186 };
 187
 188 enum {
 189         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 190
 191         Opt_xprt_err
 192 };
 193
 194 static const match_table_t nfs_xprt_protocol_tokens = {
 195         { Opt_xprt_udp, "udp" },
 196         { Opt_xprt_udp6, "udp6" },
 197         { Opt_xprt_tcp, "tcp" },
 198         { Opt_xprt_tcp6, "tcp6" },
 199         { Opt_xprt_rdma, "rdma" },
 200
 201         { Opt_xprt_err, NULL }
 202 };
 203
 204 enum {
 205         Opt_sec_none, Opt_sec_sys,
 206         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 207         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 208         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 209
 210         Opt_sec_err
 211 };
 212
 213 static const match_table_t nfs_secflavor_tokens = {
 214         { Opt_sec_none, "none" },
 215         { Opt_sec_none, "null" },
 216         { Opt_sec_sys, "sys" },
 217
 218         { Opt_sec_krb5, "krb5" },
 219         { Opt_sec_krb5i, "krb5i" },
 220         { Opt_sec_krb5p, "krb5p" },
 221
 222         { Opt_sec_lkey, "lkey" },
 223         { Opt_sec_lkeyi, "lkeyi" },
 224         { Opt_sec_lkeyp, "lkeyp" },
 225
 226         { Opt_sec_spkm, "spkm3" },
 227         { Opt_sec_spkmi, "spkm3i" },
 228         { Opt_sec_spkmp, "spkm3p" },
 229
 230         { Opt_sec_err, NULL }
 231 };
 232
 233 enum {
 234         Opt_lookupcache_all, Opt_lookupcache_positive,
 235         Opt_lookupcache_none,
 236
 237         Opt_lookupcache_err
 238 };
 239
 240 static match_table_t nfs_lookupcache_tokens = {
 241         { Opt_lookupcache_all, "all" },
 242         { Opt_lookupcache_positive, "pos" },
 243         { Opt_lookupcache_positive, "positive" },
 244         { Opt_lookupcache_none, "none" },
 245
 246         { Opt_lookupcache_err, NULL }
 247 };
 248
 249 enum {
 250         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 251         Opt_local_lock_none,
 252
 253         Opt_local_lock_err
 254 };
 255
 256 static match_table_t nfs_local_lock_tokens = {
 257         { Opt_local_lock_all, "all" },
 258         { Opt_local_lock_flock, "flock" },
 259         { Opt_local_lock_posix, "posix" },
 260         { Opt_local_lock_none, "none" },
 261
 262         { Opt_local_lock_err, NULL }
 263 };
 264
 265
 266 static void nfs_umount_begin(struct super_block *);
 267 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 268 static int  nfs_show_options(struct seq_file *, struct dentry *);
 269 static int  nfs_show_devname(struct seq_file *, struct dentry *);
 270 static int  nfs_show_path(struct seq_file *, struct dentry *);
 271 static int  nfs_show_stats(struct seq_file *, struct dentry *);
 272 static struct dentry *nfs_fs_mount(struct file_system_type *,
 273                 int, const char *, void *);
 274 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 275                 int flags, const char *dev_name, void *raw_data);
 276 static void nfs_put_super(struct super_block *);
 277 static void nfs_kill_super(struct super_block *);
 278 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 279
 280 static struct file_system_type nfs_fs_type = {
 281         .owner          = THIS_MODULE,
 282         .name           = "nfs",
 283         .mount          = nfs_fs_mount,
 284         .kill_sb        = nfs_kill_super,
 285         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 286 };
 287
 288 struct file_system_type nfs_xdev_fs_type = {
 289         .owner          = THIS_MODULE,
 290         .name           = "nfs",
 291         .mount          = nfs_xdev_mount,
 292         .kill_sb        = nfs_kill_super,
 293         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 294 };
 295
 296 static const struct super_operations nfs_sops = {
 297         .alloc_inode    = nfs_alloc_inode,
 298         .destroy_inode  = nfs_destroy_inode,
 299         .write_inode    = nfs_write_inode,
 300         .put_super      = nfs_put_super,
 301         .statfs         = nfs_statfs,
 302         .evict_inode    = nfs_evict_inode,
 303         .umount_begin   = nfs_umount_begin,
 304         .show_options   = nfs_show_options,
 305         .show_devname   = nfs_show_devname,
 306         .show_path      = nfs_show_path,
 307         .show_stats     = nfs_show_stats,
 308         .remount_fs     = nfs_remount,
 309 };
 310
 311 #ifdef CONFIG_NFS_V4
 312 static int nfs4_validate_text_mount_data(void *options,
 313         struct nfs_parsed_mount_data *args, const char *dev_name);
 314 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
 315         struct nfs_parsed_mount_data *data);
 316 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
 317         int flags, const char *dev_name, void *raw_data);
 318 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
 319         int flags, const char *dev_name, void *raw_data);
 320 static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
 321         int flags, const char *dev_name, void *raw_data);
 322 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
 323         int flags, const char *dev_name, void *raw_data);
 324 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
 325         int flags, const char *dev_name, void *raw_data);
 326 static void nfs4_kill_super(struct super_block *sb);
 327
 328 static struct file_system_type nfs4_fs_type = {
 329         .owner          = THIS_MODULE,
 330         .name           = "nfs4",
 331         .mount          = nfs4_mount,
 332         .kill_sb        = nfs4_kill_super,
 333         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 334 };
 335
 336 static struct file_system_type nfs4_remote_fs_type = {
 337         .owner          = THIS_MODULE,
 338         .name           = "nfs4",
 339         .mount          = nfs4_remote_mount,
 340         .kill_sb        = nfs4_kill_super,
 341         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 342 };
 343
 344 struct file_system_type nfs4_xdev_fs_type = {
 345         .owner          = THIS_MODULE,
 346         .name           = "nfs4",
 347         .mount          = nfs4_xdev_mount,
 348         .kill_sb        = nfs4_kill_super,
 349         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 350 };
 351
 352 static struct file_system_type nfs4_remote_referral_fs_type = {
 353         .owner          = THIS_MODULE,
 354         .name           = "nfs4",
 355         .mount          = nfs4_remote_referral_mount,
 356         .kill_sb        = nfs4_kill_super,
 357         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 358 };
 359
 360 struct file_system_type nfs4_referral_fs_type = {
 361         .owner          = THIS_MODULE,
 362         .name           = "nfs4",
 363         .mount          = nfs4_referral_mount,
 364         .kill_sb        = nfs4_kill_super,
 365         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 366 };
 367
 368 static const struct super_operations nfs4_sops = {
 369         .alloc_inode    = nfs_alloc_inode,
 370         .destroy_inode  = nfs_destroy_inode,
 371         .write_inode    = nfs_write_inode,
 372         .put_super      = nfs_put_super,
 373         .statfs         = nfs_statfs,
 374         .evict_inode    = nfs4_evict_inode,
 375         .umount_begin   = nfs_umount_begin,
 376         .show_options   = nfs_show_options,
 377         .show_devname   = nfs_show_devname,
 378         .show_path      = nfs_show_path,
 379         .show_stats     = nfs_show_stats,
 380         .remount_fs     = nfs_remount,
 381 };
 382 #endif
 383
 384 static struct shrinker acl_shrinker = {
 385         .shrink         = nfs_access_cache_shrinker,
 386         .seeks          = DEFAULT_SEEKS,
 387 };
 388
 389 /*
 390  * Register the NFS filesystems
 391  */
 392 int __init register_nfs_fs(void)
 393 {
 394         int ret;
 395
 396         ret = register_filesystem(&nfs_fs_type);
 397         if (ret < 0)
 398                 goto error_0;
 399
 400         ret = nfs_register_sysctl();
 401         if (ret < 0)
 402                 goto error_1;
 403 #ifdef CONFIG_NFS_V4
 404         ret = register_filesystem(&nfs4_fs_type);
 405         if (ret < 0)
 406                 goto error_2;
 407 #endif
 408         register_shrinker(&acl_shrinker);
 409         return 0;
 410
 411 #ifdef CONFIG_NFS_V4
 412 error_2:
 413         nfs_unregister_sysctl();
 414 #endif
 415 error_1:
 416         unregister_filesystem(&nfs_fs_type);
 417 error_0:
 418         return ret;
 419 }
 420
 421 /*
 422  * Unregister the NFS filesystems
 423  */
 424 void __exit unregister_nfs_fs(void)
 425 {
 426         unregister_shrinker(&acl_shrinker);
 427 #ifdef CONFIG_NFS_V4
 428         unregister_filesystem(&nfs4_fs_type);
 429 #endif
 430         nfs_unregister_sysctl();
 431         unregister_filesystem(&nfs_fs_type);
 432 }
 433
 434 void nfs_sb_active(struct super_block *sb)
 435 {
 436         struct nfs_server *server = NFS_SB(sb);
 437
 438         if (atomic_inc_return(&server->active) == 1)
 439                 atomic_inc(&sb->s_active);
 440 }
 441
 442 void nfs_sb_deactive(struct super_block *sb)
 443 {
 444         struct nfs_server *server = NFS_SB(sb);
 445
 446         if (atomic_dec_and_test(&server->active))
 447                 deactivate_super(sb);
 448 }
 449
 450 /*
 451  * Deliver file system statistics to userspace
 452  */
 453 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 454 {
 455         struct nfs_server *server = NFS_SB(dentry->d_sb);
 456         unsigned char blockbits;
 457         unsigned long blockres;
 458         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 459         struct nfs_fsstat res;
 460         int error = -ENOMEM;
 461
 462         res.fattr = nfs_alloc_fattr();
 463         if (res.fattr == NULL)
 464                 goto out_err;
 465
 466         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 467         if (unlikely(error == -ESTALE)) {
 468                 struct dentry *pd_dentry;
 469
 470                 pd_dentry = dget_parent(dentry);
 471                 if (pd_dentry != NULL) {
 472                         nfs_zap_caches(pd_dentry->d_inode);
 473                         dput(pd_dentry);
 474                 }
 475         }
 476         nfs_free_fattr(res.fattr);
 477         if (error < 0)
 478                 goto out_err;
 479
 480         buf->f_type = NFS_SUPER_MAGIC;
 481
 482         /*
 483          * Current versions of glibc do not correctly handle the
 484          * case where f_frsize != f_bsize.  Eventually we want to
 485          * report the value of wtmult in this field.
 486          */
 487         buf->f_frsize = dentry->d_sb->s_blocksize;
 488
 489         /*
 490          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 491          * are reported in units of f_frsize.  Linux hasn't had
 492          * an f_frsize field in its statfs struct until recently,
 493          * thus historically Linux's sys_statfs reports these
 494          * fields in units of f_bsize.
 495          */
 496         buf->f_bsize = dentry->d_sb->s_blocksize;
 497         blockbits = dentry->d_sb->s_blocksize_bits;
 498         blockres = (1 << blockbits) - 1;
 499         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 500         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 501         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 502
 503         buf->f_files = res.tfiles;
 504         buf->f_ffree = res.afiles;
 505
 506         buf->f_namelen = server->namelen;
 507
 508         return 0;
 509
 510  out_err:
 511         dprintk("%s: statfs error = %d\n", __func__, -error);
 512         return error;
 513 }
 514
 515 /*
 516  * Map the security flavour number to a name
 517  */
 518 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 519 {
 520         static const struct {
 521                 rpc_authflavor_t flavour;
 522                 const char *str;
 523         } sec_flavours[] = {
 524                 { RPC_AUTH_NULL, "null" },
 525                 { RPC_AUTH_UNIX, "sys" },
 526                 { RPC_AUTH_GSS_KRB5, "krb5" },
 527                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 528                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 529                 { RPC_AUTH_GSS_LKEY, "lkey" },
 530                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 531                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 532                 { RPC_AUTH_GSS_SPKM, "spkm" },
 533                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 534                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 535                 { UINT_MAX, "unknown" }
 536         };
 537         int i;
 538
 539         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 540                 if (sec_flavours[i].flavour == flavour)
 541                         break;
 542         }
 543         return sec_flavours[i].str;
 544 }
 545
 546 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 547                                   int showdefaults)
 548 {
 549         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 550
 551         seq_printf(m, ",mountproto=");
 552         switch (sap->sa_family) {
 553         case AF_INET:
 554                 switch (nfss->mountd_protocol) {
 555                 case IPPROTO_UDP:
 556                         seq_printf(m, RPCBIND_NETID_UDP);
 557                         break;
 558                 case IPPROTO_TCP:
 559                         seq_printf(m, RPCBIND_NETID_TCP);
 560                         break;
 561                 default:
 562                         if (showdefaults)
 563                                 seq_printf(m, "auto");
 564                 }
 565                 break;
 566         case AF_INET6:
 567                 switch (nfss->mountd_protocol) {
 568                 case IPPROTO_UDP:
 569                         seq_printf(m, RPCBIND_NETID_UDP6);
 570                         break;
 571                 case IPPROTO_TCP:
 572                         seq_printf(m, RPCBIND_NETID_TCP6);
 573                         break;
 574                 default:
 575                         if (showdefaults)
 576                                 seq_printf(m, "auto");
 577                 }
 578                 break;
 579         default:
 580                 if (showdefaults)
 581                         seq_printf(m, "auto");
 582         }
 583 }
 584
 585 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 586                                     int showdefaults)
 587 {
 588         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 589
 590         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 591                 return;
 592
 593         switch (sap->sa_family) {
 594         case AF_INET: {
 595                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 596                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 597                 break;
 598         }
 599         case AF_INET6: {
 600                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 601                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 602                 break;
 603         }
 604         default:
 605                 if (showdefaults)
 606                         seq_printf(m, ",mountaddr=unspecified");
 607         }
 608
 609         if (nfss->mountd_version || showdefaults)
 610                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 611         if ((nfss->mountd_port &&
 612                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 613                 showdefaults)
 614                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 615
 616         nfs_show_mountd_netid(m, nfss, showdefaults);
 617 }
 618
 619 #ifdef CONFIG_NFS_V4
 620 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 621                                     int showdefaults)
 622 {
 623         struct nfs_client *clp = nfss->nfs_client;
 624
 625         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 626         seq_printf(m, ",minorversion=%u", clp->cl_minorversion);
 627 }
 628 #else
 629 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 630                                     int showdefaults)
 631 {
 632 }
 633 #endif
 634
 635 /*
 636  * Describe the mount options in force on this server representation
 637  */
 638 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 639                                    int showdefaults)
 640 {
 641         static const struct proc_nfs_info {
 642                 int flag;
 643                 const char *str;
 644                 const char *nostr;
 645         } nfs_info[] = {
 646                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 647                 { NFS_MOUNT_POSIX, ",posix", "" },
 648                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 649                 { NFS_MOUNT_NOAC, ",noac", "" },
 650                 { NFS_MOUNT_NONLM, ",nolock", "" },
 651                 { NFS_MOUNT_NOACL, ",noacl", "" },
 652                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 653                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 654                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 655                 { 0, NULL, NULL }
 656         };
 657         const struct proc_nfs_info *nfs_infop;
 658         struct nfs_client *clp = nfss->nfs_client;
 659         u32 version = clp->rpc_ops->version;
 660         int local_flock, local_fcntl;
 661
 662         seq_printf(m, ",vers=%u", version);
 663         seq_printf(m, ",rsize=%u", nfss->rsize);
 664         seq_printf(m, ",wsize=%u", nfss->wsize);
 665         if (nfss->bsize != 0)
 666                 seq_printf(m, ",bsize=%u", nfss->bsize);
 667         seq_printf(m, ",namlen=%u", nfss->namelen);
 668         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 669                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 670         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 671                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 672         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 673                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 674         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 675                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 676         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 677                 if (nfss->flags & nfs_infop->flag)
 678                         seq_puts(m, nfs_infop->str);
 679                 else
 680                         seq_puts(m, nfs_infop->nostr);
 681         }
 682         seq_printf(m, ",proto=%s",
 683                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 684         if (version == 4) {
 685                 if (nfss->port != NFS_PORT)
 686                         seq_printf(m, ",port=%u", nfss->port);
 687         } else
 688                 if (nfss->port)
 689                         seq_printf(m, ",port=%u", nfss->port);
 690
 691         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 692         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 693         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 694
 695         if (version != 4)
 696                 nfs_show_mountd_options(m, nfss, showdefaults);
 697         else
 698                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 699
 700         if (nfss->options & NFS_OPTION_FSCACHE)
 701                 seq_printf(m, ",fsc");
 702
 703         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 704                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 705                         seq_printf(m, ",lookupcache=none");
 706                 else
 707                         seq_printf(m, ",lookupcache=pos");
 708         }
 709
 710         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 711         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 712
 713         if (!local_flock && !local_fcntl)
 714                 seq_printf(m, ",local_lock=none");
 715         else if (local_flock && local_fcntl)
 716                 seq_printf(m, ",local_lock=all");
 717         else if (local_flock)
 718                 seq_printf(m, ",local_lock=flock");
 719         else
 720                 seq_printf(m, ",local_lock=posix");
 721 }
 722
 723 /*
 724  * Describe the mount options on this VFS mountpoint
 725  */
 726 static int nfs_show_options(struct seq_file *m, struct dentry *root)
 727 {
 728         struct nfs_server *nfss = NFS_SB(root->d_sb);
 729
 730         nfs_show_mount_options(m, nfss, 0);
 731
 732         seq_printf(m, ",addr=%s",
 733                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 734                                                         RPC_DISPLAY_ADDR));
 735
 736         return 0;
 737 }
 738
 739 #ifdef CONFIG_NFS_V4
 740 #ifdef CONFIG_NFS_V4_1
 741 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 742 {
 743         if (nfs4_has_session(server->nfs_client))
 744                 seq_printf(m, ",sessions");
 745 }
 746 #else
 747 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 748 #endif
 749 #endif
 750
 751 #ifdef CONFIG_NFS_V4
 752 #ifdef CONFIG_NFS_V4_1
 753 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 754 {
 755         seq_printf(m, ",pnfs=");
 756         if (server->pnfs_curr_ld)
 757                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 758         else
 759                 seq_printf(m, "not configured");
 760 }
 761 #else
 762 static void show_pnfs(struct seq_file *m, struct nfs_server *server) {}
 763 #endif
 764 #endif
 765
 766 static int nfs_show_devname(struct seq_file *m, struct dentry *root)
 767 {
 768         char *page = (char *) __get_free_page(GFP_KERNEL);
 769         char *devname, *dummy;
 770         int err = 0;
 771         if (!page)
 772                 return -ENOMEM;
 773         devname = nfs_path(&dummy, root, page, PAGE_SIZE);
 774         if (IS_ERR(devname))
 775                 err = PTR_ERR(devname);
 776         else
 777                 seq_escape(m, devname, " \t\n\\");
 778         free_page((unsigned long)page);
 779         return err;
 780 }
 781
 782 static int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 783 {
 784         seq_puts(m, "/");
 785         return 0;
 786 }
 787
 788 /*
 789  * Present statistical information for this VFS mountpoint
 790  */
 791 static int nfs_show_stats(struct seq_file *m, struct dentry *root)
 792 {
 793         int i, cpu;
 794         struct nfs_server *nfss = NFS_SB(root->d_sb);
 795         struct rpc_auth *auth = nfss->client->cl_auth;
 796         struct nfs_iostats totals = { };
 797
 798         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 799
 800         /*
 801          * Display all mount option settings
 802          */
 803         seq_printf(m, "\n\topts:\t");
 804         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 805         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 806         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 807         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 808         nfs_show_mount_options(m, nfss, 1);
 809
 810         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 811
 812         seq_printf(m, "\n\tcaps:\t");
 813         seq_printf(m, "caps=0x%x", nfss->caps);
 814         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 815         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 816         seq_printf(m, ",bsize=%u", nfss->bsize);
 817         seq_printf(m, ",namlen=%u", nfss->namelen);
 818
 819 #ifdef CONFIG_NFS_V4
 820         if (nfss->nfs_client->rpc_ops->version == 4) {
 821                 seq_printf(m, "\n\tnfsv4:\t");
 822                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 823                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 824                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 825                 show_sessions(m, nfss);
 826                 show_pnfs(m, nfss);
 827         }
 828 #endif
 829
 830         /*
 831          * Display security flavor in effect for this mount
 832          */
 833         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 834         if (auth->au_flavor)
 835                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 836
 837         /*
 838          * Display superblock I/O counters
 839          */
 840         for_each_possible_cpu(cpu) {
 841                 struct nfs_iostats *stats;
 842
 843                 preempt_disable();
 844                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 845
 846                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 847                         totals.events[i] += stats->events[i];
 848                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 849                         totals.bytes[i] += stats->bytes[i];
 850 #ifdef CONFIG_NFS_FSCACHE
 851                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 852                         totals.fscache[i] += stats->fscache[i];
 853 #endif
 854
 855                 preempt_enable();
 856         }
 857
 858         seq_printf(m, "\n\tevents:\t");
 859         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 860                 seq_printf(m, "%lu ", totals.events[i]);
 861         seq_printf(m, "\n\tbytes:\t");
 862         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 863                 seq_printf(m, "%Lu ", totals.bytes[i]);
 864 #ifdef CONFIG_NFS_FSCACHE
 865         if (nfss->options & NFS_OPTION_FSCACHE) {
 866                 seq_printf(m, "\n\tfsc:\t");
 867                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 868                         seq_printf(m, "%Lu ", totals.bytes[i]);
 869         }
 870 #endif
 871         seq_printf(m, "\n");
 872
 873         rpc_print_iostats(m, nfss->client);
 874
 875         return 0;
 876 }
 877
 878 /*
 879  * Begin unmount by attempting to remove all automounted mountpoints we added
 880  * in response to xdev traversals and referrals
 881  */
 882 static void nfs_umount_begin(struct super_block *sb)
 883 {
 884         struct nfs_server *server;
 885         struct rpc_clnt *rpc;
 886
 887         server = NFS_SB(sb);
 888         /* -EIO all pending I/O */
 889         rpc = server->client_acl;
 890         if (!IS_ERR(rpc))
 891                 rpc_killall_tasks(rpc);
 892         rpc = server->client;
 893         if (!IS_ERR(rpc))
 894                 rpc_killall_tasks(rpc);
 895 }
 896
 897 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
 898 {
 899         struct nfs_parsed_mount_data *data;
 900
 901         data = kzalloc(sizeof(*data), GFP_KERNEL);
 902         if (data) {
 903                 data->acregmin          = NFS_DEF_ACREGMIN;
 904                 data->acregmax          = NFS_DEF_ACREGMAX;
 905                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 906                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 907                 data->mount_server.port = NFS_UNSPEC_PORT;
 908                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 909                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 910                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 911                 data->auth_flavor_len   = 1;
 912                 data->version           = version;
 913                 data->minorversion      = 0;
 914                 security_init_mnt_opts(&data->lsm_opts);
 915         }
 916         return data;
 917 }
 918
 919 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 920 {
 921         if (data) {
 922                 kfree(data->client_address);
 923                 kfree(data->mount_server.hostname);
 924                 kfree(data->nfs_server.export_path);
 925                 kfree(data->nfs_server.hostname);
 926                 kfree(data->fscache_uniq);
 927                 security_free_mnt_opts(&data->lsm_opts);
 928                 kfree(data);
 929         }
 930 }
 931
 932 /*
 933  * Sanity-check a server address provided by the mount command.
 934  *
 935  * Address family must be initialized, and address must not be
 936  * the ANY address for that family.
 937  */
 938 static int nfs_verify_server_address(struct sockaddr *addr)
 939 {
 940         switch (addr->sa_family) {
 941         case AF_INET: {
 942                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 943                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 944         }
 945         case AF_INET6: {
 946                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 947                 return !ipv6_addr_any(sa);
 948         }
 949         }
 950
 951         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 952         return 0;
 953 }
 954
 955 /*
 956  * Select between a default port value and a user-specified port value.
 957  * If a zero value is set, then autobind will be used.
 958  */
 959 static void nfs_set_port(struct sockaddr *sap, int *port,
 960                                  const unsigned short default_port)
 961 {
 962         if (*port == NFS_UNSPEC_PORT)
 963                 *port = default_port;
 964
 965         rpc_set_port(sap, *port);
 966 }
 967
 968 /*
 969  * Sanity check the NFS transport protocol.
 970  *
 971  */
 972 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 973 {
 974         switch (mnt->nfs_server.protocol) {
 975         case XPRT_TRANSPORT_UDP:
 976         case XPRT_TRANSPORT_TCP:
 977         case XPRT_TRANSPORT_RDMA:
 978                 break;
 979         default:
 980                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 981         }
 982 }
 983
 984 /*
 985  * For text based NFSv2/v3 mounts, the mount protocol transport default
 986  * settings should depend upon the specified NFS transport.
 987  */
 988 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 989 {
 990         nfs_validate_transport_protocol(mnt);
 991
 992         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 993             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 994                         return;
 995         switch (mnt->nfs_server.protocol) {
 996         case XPRT_TRANSPORT_UDP:
 997                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 998                 break;
 999         case XPRT_TRANSPORT_TCP:
1000         case XPRT_TRANSPORT_RDMA:
1001                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1002         }
1003 }
1004
1005 /*
1006  * Parse the value of the 'sec=' option.
1007  */
1008 static int nfs_parse_security_flavors(char *value,
1009                                       struct nfs_parsed_mount_data *mnt)
1010 {
1011         substring_t args[MAX_OPT_ARGS];
1012
1013         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1014
1015         switch (match_token(value, nfs_secflavor_tokens, args)) {
1016         case Opt_sec_none:
1017                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1018                 break;
1019         case Opt_sec_sys:
1020                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1021                 break;
1022         case Opt_sec_krb5:
1023                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1024                 break;
1025         case Opt_sec_krb5i:
1026                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1027                 break;
1028         case Opt_sec_krb5p:
1029                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1030                 break;
1031         case Opt_sec_lkey:
1032                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1033                 break;
1034         case Opt_sec_lkeyi:
1035                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1036                 break;
1037         case Opt_sec_lkeyp:
1038                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1039                 break;
1040         case Opt_sec_spkm:
1041                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1042                 break;
1043         case Opt_sec_spkmi:
1044                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1045                 break;
1046         case Opt_sec_spkmp:
1047                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1048                 break;
1049         default:
1050                 return 0;
1051         }
1052
1053         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1054         mnt->auth_flavor_len = 1;
1055         return 1;
1056 }
1057
1058 static int nfs_get_option_str(substring_t args[], char **option)
1059 {
1060         kfree(*option);
1061         *option = match_strdup(args);
1062         return !option;
1063 }
1064
1065 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1066 {
1067         int rc;
1068         char *string;
1069
1070         string = match_strdup(args);
1071         if (string == NULL)
1072                 return -ENOMEM;
1073         rc = strict_strtoul(string, 10, option);
1074         kfree(string);
1075
1076         return rc;
1077 }
1078
1079 /*
1080  * Error-check and convert a string of mount options from user space into
1081  * a data structure.  The whole mount string is processed; bad options are
1082  * skipped as they are encountered.  If there were no errors, return 1;
1083  * otherwise return 0 (zero).
1084  */
1085 static int nfs_parse_mount_options(char *raw,
1086                                    struct nfs_parsed_mount_data *mnt)
1087 {
1088         char *p, *string, *secdata;
1089         int rc, sloppy = 0, invalid_option = 0;
1090         unsigned short protofamily = AF_UNSPEC;
1091         unsigned short mountfamily = AF_UNSPEC;
1092
1093         if (!raw) {
1094                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1095                 return 1;
1096         }
1097         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1098
1099         secdata = alloc_secdata();
1100         if (!secdata)
1101                 goto out_nomem;
1102
1103         rc = security_sb_copy_data(raw, secdata);
1104         if (rc)
1105                 goto out_security_failure;
1106
1107         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1108         if (rc)
1109                 goto out_security_failure;
1110
1111         free_secdata(secdata);
1112
1113         mnt->net = current->nsproxy->net_ns;
1114
1115         while ((p = strsep(&raw, ",")) != NULL) {
1116                 substring_t args[MAX_OPT_ARGS];
1117                 unsigned long option;
1118                 int token;
1119
1120                 if (!*p)
1121                         continue;
1122
1123                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1124
1125                 token = match_token(p, nfs_mount_option_tokens, args);
1126                 switch (token) {
1127
1128                 /*
1129                  * boolean options:  foo/nofoo
1130                  */
1131                 case Opt_soft:
1132                         mnt->flags |= NFS_MOUNT_SOFT;
1133                         break;
1134                 case Opt_hard:
1135                         mnt->flags &= ~NFS_MOUNT_SOFT;
1136                         break;
1137                 case Opt_posix:
1138                         mnt->flags |= NFS_MOUNT_POSIX;
1139                         break;
1140                 case Opt_noposix:
1141                         mnt->flags &= ~NFS_MOUNT_POSIX;
1142                         break;
1143                 case Opt_cto:
1144                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1145                         break;
1146                 case Opt_nocto:
1147                         mnt->flags |= NFS_MOUNT_NOCTO;
1148                         break;
1149                 case Opt_ac:
1150                         mnt->flags &= ~NFS_MOUNT_NOAC;
1151                         break;
1152                 case Opt_noac:
1153                         mnt->flags |= NFS_MOUNT_NOAC;
1154                         break;
1155                 case Opt_lock:
1156                         mnt->flags &= ~NFS_MOUNT_NONLM;
1157                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1158                                         NFS_MOUNT_LOCAL_FCNTL);
1159                         break;
1160                 case Opt_nolock:
1161                         mnt->flags |= NFS_MOUNT_NONLM;
1162                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1163                                        NFS_MOUNT_LOCAL_FCNTL);
1164                         break;
1165                 case Opt_v2:
1166                         mnt->flags &= ~NFS_MOUNT_VER3;
1167                         mnt->version = 2;
1168                         break;
1169                 case Opt_v3:
1170                         mnt->flags |= NFS_MOUNT_VER3;
1171                         mnt->version = 3;
1172                         break;
1173                 case Opt_v4:
1174                         mnt->flags &= ~NFS_MOUNT_VER3;
1175                         mnt->version = 4;
1176                         break;
1177                 case Opt_v4_0:
1178                         mnt->flags &= ~NFS_MOUNT_VER3;
1179                         mnt->version = 4;
1180                         mnt->minorversion = 0;
1181                         break;
1182                 case Opt_v4_1:
1183                         mnt->flags &= ~NFS_MOUNT_VER3;
1184                         mnt->version = 4;
1185                         mnt->minorversion = 1;
1186                         break;
1187                 case Opt_udp:
1188                         mnt->flags &= ~NFS_MOUNT_TCP;
1189                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1190                         break;
1191                 case Opt_tcp:
1192                         mnt->flags |= NFS_MOUNT_TCP;
1193                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1194                         break;
1195                 case Opt_rdma:
1196                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1197                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1198                         xprt_load_transport(p);
1199                         break;
1200                 case Opt_acl:
1201                         mnt->flags &= ~NFS_MOUNT_NOACL;
1202                         break;
1203                 case Opt_noacl:
1204                         mnt->flags |= NFS_MOUNT_NOACL;
1205                         break;
1206                 case Opt_rdirplus:
1207                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1208                         break;
1209                 case Opt_nordirplus:
1210                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1211                         break;
1212                 case Opt_sharecache:
1213                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1214                         break;
1215                 case Opt_nosharecache:
1216                         mnt->flags |= NFS_MOUNT_UNSHARED;
1217                         break;
1218                 case Opt_resvport:
1219                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1220                         break;
1221                 case Opt_noresvport:
1222                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1223                         break;
1224                 case Opt_fscache:
1225                         mnt->options |= NFS_OPTION_FSCACHE;
1226                         kfree(mnt->fscache_uniq);
1227                         mnt->fscache_uniq = NULL;
1228                         break;
1229                 case Opt_nofscache:
1230                         mnt->options &= ~NFS_OPTION_FSCACHE;
1231                         kfree(mnt->fscache_uniq);
1232                         mnt->fscache_uniq = NULL;
1233                         break;
1234
1235                 /*
1236                  * options that take numeric values
1237                  */
1238                 case Opt_port:
1239                         if (nfs_get_option_ul(args, &option) ||
1240                             option > USHRT_MAX)
1241                                 goto out_invalid_value;
1242                         mnt->nfs_server.port = option;
1243                         break;
1244                 case Opt_rsize:
1245                         if (nfs_get_option_ul(args, &option))
1246                                 goto out_invalid_value;
1247                         mnt->rsize = option;
1248                         break;
1249                 case Opt_wsize:
1250                         if (nfs_get_option_ul(args, &option))
1251                                 goto out_invalid_value;
1252                         mnt->wsize = option;
1253                         break;
1254                 case Opt_bsize:
1255                         if (nfs_get_option_ul(args, &option))
1256                                 goto out_invalid_value;
1257                         mnt->bsize = option;
1258                         break;
1259                 case Opt_timeo:
1260                         if (nfs_get_option_ul(args, &option) || option == 0)
1261                                 goto out_invalid_value;
1262                         mnt->timeo = option;
1263                         break;
1264                 case Opt_retrans:
1265                         if (nfs_get_option_ul(args, &option) || option == 0)
1266                                 goto out_invalid_value;
1267                         mnt->retrans = option;
1268                         break;
1269                 case Opt_acregmin:
1270                         if (nfs_get_option_ul(args, &option))
1271                                 goto out_invalid_value;
1272                         mnt->acregmin = option;
1273                         break;
1274                 case Opt_acregmax:
1275                         if (nfs_get_option_ul(args, &option))
1276                                 goto out_invalid_value;
1277                         mnt->acregmax = option;
1278                         break;
1279                 case Opt_acdirmin:
1280                         if (nfs_get_option_ul(args, &option))
1281                                 goto out_invalid_value;
1282                         mnt->acdirmin = option;
1283                         break;
1284                 case Opt_acdirmax:
1285                         if (nfs_get_option_ul(args, &option))
1286                                 goto out_invalid_value;
1287                         mnt->acdirmax = option;
1288                         break;
1289                 case Opt_actimeo:
1290                         if (nfs_get_option_ul(args, &option))
1291                                 goto out_invalid_value;
1292                         mnt->acregmin = mnt->acregmax =
1293                         mnt->acdirmin = mnt->acdirmax = option;
1294                         break;
1295                 case Opt_namelen:
1296                         if (nfs_get_option_ul(args, &option))
1297                                 goto out_invalid_value;
1298                         mnt->namlen = option;
1299                         break;
1300                 case Opt_mountport:
1301                         if (nfs_get_option_ul(args, &option) ||
1302                             option > USHRT_MAX)
1303                                 goto out_invalid_value;
1304                         mnt->mount_server.port = option;
1305                         break;
1306                 case Opt_mountvers:
1307                         if (nfs_get_option_ul(args, &option) ||
1308                             option < NFS_MNT_VERSION ||
1309                             option > NFS_MNT3_VERSION)
1310                                 goto out_invalid_value;
1311                         mnt->mount_server.version = option;
1312                         break;
1313                 case Opt_nfsvers:
1314                         if (nfs_get_option_ul(args, &option))
1315                                 goto out_invalid_value;
1316                         switch (option) {
1317                         case NFS2_VERSION:
1318                                 mnt->flags &= ~NFS_MOUNT_VER3;
1319                                 mnt->version = 2;
1320                                 break;
1321                         case NFS3_VERSION:
1322                                 mnt->flags |= NFS_MOUNT_VER3;
1323                                 mnt->version = 3;
1324                                 break;
1325                         case NFS4_VERSION:
1326                                 mnt->flags &= ~NFS_MOUNT_VER3;
1327                                 mnt->version = 4;
1328                                 break;
1329                         default:
1330                                 goto out_invalid_value;
1331                         }
1332                         break;
1333                 case Opt_minorversion:
1334                         if (nfs_get_option_ul(args, &option))
1335                                 goto out_invalid_value;
1336                         if (option > NFS4_MAX_MINOR_VERSION)
1337                                 goto out_invalid_value;
1338                         mnt->minorversion = option;
1339                         break;
1340
1341                 /*
1342                  * options that take text values
1343                  */
1344                 case Opt_sec:
1345                         string = match_strdup(args);
1346                         if (string == NULL)
1347                                 goto out_nomem;
1348                         rc = nfs_parse_security_flavors(string, mnt);
1349                         kfree(string);
1350                         if (!rc) {
1351                                 dfprintk(MOUNT, "NFS:   unrecognized "
1352                                                 "security flavor\n");
1353                                 return 0;
1354                         }
1355                         break;
1356                 case Opt_proto:
1357                         string = match_strdup(args);
1358                         if (string == NULL)
1359                                 goto out_nomem;
1360                         token = match_token(string,
1361                                             nfs_xprt_protocol_tokens, args);
1362
1363                         protofamily = AF_INET;
1364                         switch (token) {
1365                         case Opt_xprt_udp6:
1366                                 protofamily = AF_INET6;
1367                         case Opt_xprt_udp:
1368                                 mnt->flags &= ~NFS_MOUNT_TCP;
1369                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1370                                 break;
1371                         case Opt_xprt_tcp6:
1372                                 protofamily = AF_INET6;
1373                         case Opt_xprt_tcp:
1374                                 mnt->flags |= NFS_MOUNT_TCP;
1375                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1376                                 break;
1377                         case Opt_xprt_rdma:
1378                                 /* vector side protocols to TCP */
1379                                 mnt->flags |= NFS_MOUNT_TCP;
1380                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1381                                 xprt_load_transport(string);
1382                                 break;
1383                         default:
1384                                 dfprintk(MOUNT, "NFS:   unrecognized "
1385                                                 "transport protocol\n");
1386                                 kfree(string);
1387                                 return 0;
1388                         }
1389                         kfree(string);
1390                         break;
1391                 case Opt_mountproto:
1392                         string = match_strdup(args);
1393                         if (string == NULL)
1394                                 goto out_nomem;
1395                         token = match_token(string,
1396                                             nfs_xprt_protocol_tokens, args);
1397                         kfree(string);
1398
1399                         mountfamily = AF_INET;
1400                         switch (token) {
1401                         case Opt_xprt_udp6:
1402                                 mountfamily = AF_INET6;
1403                         case Opt_xprt_udp:
1404                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1405                                 break;
1406                         case Opt_xprt_tcp6:
1407                                 mountfamily = AF_INET6;
1408                         case Opt_xprt_tcp:
1409                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1410                                 break;
1411                         case Opt_xprt_rdma: /* not used for side protocols */
1412                         default:
1413                                 dfprintk(MOUNT, "NFS:   unrecognized "
1414                                                 "transport protocol\n");
1415                                 return 0;
1416                         }
1417                         break;
1418                 case Opt_addr:
1419                         string = match_strdup(args);
1420                         if (string == NULL)
1421                                 goto out_nomem;
1422                         mnt->nfs_server.addrlen =
1423                                 rpc_pton(mnt->net, string, strlen(string),
1424                                         (struct sockaddr *)
1425                                         &mnt->nfs_server.address,
1426                                         sizeof(mnt->nfs_server.address));
1427                         kfree(string);
1428                         if (mnt->nfs_server.addrlen == 0)
1429                                 goto out_invalid_address;
1430                         break;
1431                 case Opt_clientaddr:
1432                         if (nfs_get_option_str(args, &mnt->client_address))
1433                                 goto out_nomem;
1434                         break;
1435                 case Opt_mounthost:
1436                         if (nfs_get_option_str(args,
1437                                                &mnt->mount_server.hostname))
1438                                 goto out_nomem;
1439                         break;
1440                 case Opt_mountaddr:
1441                         string = match_strdup(args);
1442                         if (string == NULL)
1443                                 goto out_nomem;
1444                         mnt->mount_server.addrlen =
1445                                 rpc_pton(mnt->net, string, strlen(string),
1446                                         (struct sockaddr *)
1447                                         &mnt->mount_server.address,
1448                                         sizeof(mnt->mount_server.address));
1449                         kfree(string);
1450                         if (mnt->mount_server.addrlen == 0)
1451                                 goto out_invalid_address;
1452                         break;
1453                 case Opt_lookupcache:
1454                         string = match_strdup(args);
1455                         if (string == NULL)
1456                                 goto out_nomem;
1457                         token = match_token(string,
1458                                         nfs_lookupcache_tokens, args);
1459                         kfree(string);
1460                         switch (token) {
1461                                 case Opt_lookupcache_all:
1462                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1463                                         break;
1464                                 case Opt_lookupcache_positive:
1465                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1466                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1467                                         break;
1468                                 case Opt_lookupcache_none:
1469                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1470                                         break;
1471                                 default:
1472                                         dfprintk(MOUNT, "NFS:   invalid "
1473                                                         "lookupcache argument\n");
1474                                         return 0;
1475                         };
1476                         break;
1477                 case Opt_fscache_uniq:
1478                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1479                                 goto out_nomem;
1480                         mnt->options |= NFS_OPTION_FSCACHE;
1481                         break;
1482                 case Opt_local_lock:
1483                         string = match_strdup(args);
1484                         if (string == NULL)
1485                                 goto out_nomem;
1486                         token = match_token(string, nfs_local_lock_tokens,
1487                                         args);
1488                         kfree(string);
1489                         switch (token) {
1490                         case Opt_local_lock_all:
1491                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1492                                                NFS_MOUNT_LOCAL_FCNTL);
1493                                 break;
1494                         case Opt_local_lock_flock:
1495                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1496                                 break;
1497                         case Opt_local_lock_posix:
1498                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1499                                 break;
1500                         case Opt_local_lock_none:
1501                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1502                                                 NFS_MOUNT_LOCAL_FCNTL);
1503                                 break;
1504                         default:
1505                                 dfprintk(MOUNT, "NFS:   invalid "
1506                                                 "local_lock argument\n");
1507                                 return 0;
1508                         };
1509                         break;
1510
1511                 /*
1512                  * Special options
1513                  */
1514                 case Opt_sloppy:
1515                         sloppy = 1;
1516                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1517                         break;
1518                 case Opt_userspace:
1519                 case Opt_deprecated:
1520                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1521                                         "'%s'\n", p);
1522                         break;
1523
1524                 default:
1525                         invalid_option = 1;
1526                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1527                                         "'%s'\n", p);
1528                 }
1529         }
1530
1531         if (!sloppy && invalid_option)
1532                 return 0;
1533
1534         if (mnt->minorversion && mnt->version != 4)
1535                 goto out_minorversion_mismatch;
1536
1537         /*
1538          * verify that any proto=/mountproto= options match the address
1539          * familiies in the addr=/mountaddr= options.
1540          */
1541         if (protofamily != AF_UNSPEC &&
1542             protofamily != mnt->nfs_server.address.ss_family)
1543                 goto out_proto_mismatch;
1544
1545         if (mountfamily != AF_UNSPEC) {
1546                 if (mnt->mount_server.addrlen) {
1547                         if (mountfamily != mnt->mount_server.address.ss_family)
1548                                 goto out_mountproto_mismatch;
1549                 } else {
1550                         if (mountfamily != mnt->nfs_server.address.ss_family)
1551                                 goto out_mountproto_mismatch;
1552                 }
1553         }
1554
1555         return 1;
1556
1557 out_mountproto_mismatch:
1558         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1559                          "option\n");
1560         return 0;
1561 out_proto_mismatch:
1562         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1563         return 0;
1564 out_invalid_address:
1565         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1566         return 0;
1567 out_invalid_value:
1568         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1569         return 0;
1570 out_minorversion_mismatch:
1571         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1572                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1573         return 0;
1574 out_nomem:
1575         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1576         return 0;
1577 out_security_failure:
1578         free_secdata(secdata);
1579         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1580         return 0;
1581 }
1582
1583 /*
1584  * Match the requested auth flavors with the list returned by
1585  * the server.  Returns zero and sets the mount's authentication
1586  * flavor on success; returns -EACCES if server does not support
1587  * the requested flavor.
1588  */
1589 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1590                              struct nfs_mount_request *request)
1591 {
1592         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1593
1594         /*
1595          * Certain releases of Linux's mountd return an empty
1596          * flavor list.  To prevent behavioral regression with
1597          * these servers (ie. rejecting mounts that used to
1598          * succeed), revert to pre-2.6.32 behavior (no checking)
1599          * if the returned flavor list is empty.
1600          */
1601         if (server_authlist_len == 0)
1602                 return 0;
1603
1604         /*
1605          * We avoid sophisticated negotiating here, as there are
1606          * plenty of cases where we can get it wrong, providing
1607          * either too little or too much security.
1608          *
1609          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1610          * flavor listed first.  However, some servers list
1611          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1612          * preferred default, in args->auth_flavors[0] if user
1613          * didn't specify sec= mount option.
1614          */
1615         for (i = 0; i < args->auth_flavor_len; i++)
1616                 for (j = 0; j < server_authlist_len; j++)
1617                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1618                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1619                                         request->auth_flavs[j]);
1620                                 args->auth_flavors[0] = request->auth_flavs[j];
1621                                 return 0;
1622                         }
1623
1624         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1625         nfs_umount(request);
1626         return -EACCES;
1627 }
1628
1629 /*
1630  * Use the remote server's MOUNT service to request the NFS file handle
1631  * corresponding to the provided path.
1632  */
1633 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1634                          struct nfs_fh *root_fh)
1635 {
1636         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1637         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1638         struct nfs_mount_request request = {
1639                 .sap            = (struct sockaddr *)
1640                                                 &args->mount_server.address,
1641                 .dirpath        = args->nfs_server.export_path,
1642                 .protocol       = args->mount_server.protocol,
1643                 .fh             = root_fh,
1644                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1645                 .auth_flav_len  = &server_authlist_len,
1646                 .auth_flavs     = server_authlist,
1647                 .net            = args->net,
1648         };
1649         int status;
1650
1651         if (args->mount_server.version == 0) {
1652                 switch (args->version) {
1653                         default:
1654                                 args->mount_server.version = NFS_MNT3_VERSION;
1655                                 break;
1656                         case 2:
1657                                 args->mount_server.version = NFS_MNT_VERSION;
1658                 }
1659         }
1660         request.version = args->mount_server.version;
1661
1662         if (args->mount_server.hostname)
1663                 request.hostname = args->mount_server.hostname;
1664         else
1665                 request.hostname = args->nfs_server.hostname;
1666
1667         /*
1668          * Construct the mount server's address.
1669          */
1670         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1671                 memcpy(request.sap, &args->nfs_server.address,
1672                        args->nfs_server.addrlen);
1673                 args->mount_server.addrlen = args->nfs_server.addrlen;
1674         }
1675         request.salen = args->mount_server.addrlen;
1676         nfs_set_port(request.sap, &args->mount_server.port, 0);
1677
1678         /*
1679          * Now ask the mount server to map our export path
1680          * to a file handle.
1681          */
1682         status = nfs_mount(&request);
1683         if (status != 0) {
1684                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1685                                 request.hostname, status);
1686                 return status;
1687         }
1688
1689         /*
1690          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1691          */
1692         if (args->mount_server.version != NFS_MNT3_VERSION)
1693                 return 0;
1694         return nfs_walk_authlist(args, &request);
1695 }
1696
1697 /*
1698  * Split "dev_name" into "hostname:export_path".
1699  *
1700  * The leftmost colon demarks the split between the server's hostname
1701  * and the export path.  If the hostname starts with a left square
1702  * bracket, then it may contain colons.
1703  *
1704  * Note: caller frees hostname and export path, even on error.
1705  */
1706 static int nfs_parse_devname(const char *dev_name,
1707                              char **hostname, size_t maxnamlen,
1708                              char **export_path, size_t maxpathlen)
1709 {
1710         size_t len;
1711         char *end;
1712
1713         /* Is the host name protected with square brakcets? */
1714         if (*dev_name == '[') {
1715                 end = strchr(++dev_name, ']');
1716                 if (end == NULL || end[1] != ':')
1717                         goto out_bad_devname;
1718
1719                 len = end - dev_name;
1720                 end++;
1721         } else {
1722                 char *comma;
1723
1724                 end = strchr(dev_name, ':');
1725                 if (end == NULL)
1726                         goto out_bad_devname;
1727                 len = end - dev_name;
1728
1729                 /* kill possible hostname list: not supported */
1730                 comma = strchr(dev_name, ',');
1731                 if (comma != NULL && comma < end)
1732                         *comma = 0;
1733         }
1734
1735         if (len > maxnamlen)
1736                 goto out_hostname;
1737
1738         /* N.B. caller will free nfs_server.hostname in all cases */
1739         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1740         if (*hostname == NULL)
1741                 goto out_nomem;
1742         len = strlen(++end);
1743         if (len > maxpathlen)
1744                 goto out_path;
1745         *export_path = kstrndup(end, len, GFP_KERNEL);
1746         if (!*export_path)
1747                 goto out_nomem;
1748
1749         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1750         return 0;
1751
1752 out_bad_devname:
1753         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1754         return -EINVAL;
1755
1756 out_nomem:
1757         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1758         return -ENOMEM;
1759
1760 out_hostname:
1761         dfprintk(MOUNT, "NFS: server hostname too long\n");
1762         return -ENAMETOOLONG;
1763
1764 out_path:
1765         dfprintk(MOUNT, "NFS: export pathname too long\n");
1766         return -ENAMETOOLONG;
1767 }
1768
1769 /*
1770  * Validate the NFS2/NFS3 mount data
1771  * - fills in the mount root filehandle
1772  *
1773  * For option strings, user space handles the following behaviors:
1774  *
1775  * + DNS: mapping server host name to IP address ("addr=" option)
1776  *
1777  * + failure mode: how to behave if a mount request can't be handled
1778  *   immediately ("fg/bg" option)
1779  *
1780  * + retry: how often to retry a mount request ("retry=" option)
1781  *
1782  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1783  *   mountproto=tcp after mountproto=udp, and so on
1784  */
1785 static int nfs_validate_mount_data(void *options,
1786                                    struct nfs_parsed_mount_data *args,
1787                                    struct nfs_fh *mntfh,
1788                                    const char *dev_name)
1789 {
1790         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1791         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1792
1793         if (data == NULL)
1794                 goto out_no_data;
1795
1796         switch (data->version) {
1797         case 1:
1798                 data->namlen = 0;
1799         case 2:
1800                 data->bsize = 0;
1801         case 3:
1802                 if (data->flags & NFS_MOUNT_VER3)
1803                         goto out_no_v3;
1804                 data->root.size = NFS2_FHSIZE;
1805                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1806         case 4:
1807                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1808                         goto out_no_sec;
1809         case 5:
1810                 memset(data->context, 0, sizeof(data->context));
1811         case 6:
1812                 if (data->flags & NFS_MOUNT_VER3) {
1813                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1814                                 goto out_invalid_fh;
1815                         mntfh->size = data->root.size;
1816                         args->version = 3;
1817                 } else {
1818                         mntfh->size = NFS2_FHSIZE;
1819                         args->version = 2;
1820                 }
1821
1822
1823                 memcpy(mntfh->data, data->root.data, mntfh->size);
1824                 if (mntfh->size < sizeof(mntfh->data))
1825                         memset(mntfh->data + mntfh->size, 0,
1826                                sizeof(mntfh->data) - mntfh->size);
1827
1828                 /*
1829                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1830                  * can deal with.
1831                  */
1832                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1833                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1834                 args->rsize             = data->rsize;
1835                 args->wsize             = data->wsize;
1836                 args->timeo             = data->timeo;
1837                 args->retrans           = data->retrans;
1838                 args->acregmin          = data->acregmin;
1839                 args->acregmax          = data->acregmax;
1840                 args->acdirmin          = data->acdirmin;
1841                 args->acdirmax          = data->acdirmax;
1842
1843                 memcpy(sap, &data->addr, sizeof(data->addr));
1844                 args->nfs_server.addrlen = sizeof(data->addr);
1845                 if (!nfs_verify_server_address(sap))
1846                         goto out_no_address;
1847
1848                 if (!(data->flags & NFS_MOUNT_TCP))
1849                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1850                 /* N.B. caller will free nfs_server.hostname in all cases */
1851                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1852                 args->namlen            = data->namlen;
1853                 args->bsize             = data->bsize;
1854
1855                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1856                         args->auth_flavors[0] = data->pseudoflavor;
1857                 if (!args->nfs_server.hostname)
1858                         goto out_nomem;
1859
1860                 if (!(data->flags & NFS_MOUNT_NONLM))
1861                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1862                                          NFS_MOUNT_LOCAL_FCNTL);
1863                 else
1864                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1865                                         NFS_MOUNT_LOCAL_FCNTL);
1866                 /*
1867                  * The legacy version 6 binary mount data from userspace has a
1868                  * field used only to transport selinux information into the
1869                  * the kernel.  To continue to support that functionality we
1870                  * have a touch of selinux knowledge here in the NFS code. The
1871                  * userspace code converted context=blah to just blah so we are
1872                  * converting back to the full string selinux understands.
1873                  */
1874                 if (data->context[0]){
1875 #ifdef CONFIG_SECURITY_SELINUX
1876                         int rc;
1877                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1878                         if (!opts_str)
1879                                 return -ENOMEM;
1880                         strcpy(opts_str, "context=");
1881                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1882                         strcat(opts_str, &data->context[0]);
1883                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1884                         kfree(opts_str);
1885                         if (rc)
1886                                 return rc;
1887 #else
1888                         return -EINVAL;
1889 #endif
1890                 }
1891
1892                 break;
1893         default: {
1894                 int status;
1895
1896                 if (nfs_parse_mount_options((char *)options, args) == 0)
1897                         return -EINVAL;
1898
1899                 if (!nfs_verify_server_address(sap))
1900                         goto out_no_address;
1901
1902                 if (args->version == 4)
1903 #ifdef CONFIG_NFS_V4
1904                         return nfs4_validate_text_mount_data(options,
1905                                                              args, dev_name);
1906 #else
1907                         goto out_v4_not_compiled;
1908 #endif
1909
1910                 nfs_set_port(sap, &args->nfs_server.port, 0);
1911
1912                 nfs_set_mount_transport_protocol(args);
1913
1914                 status = nfs_parse_devname(dev_name,
1915                                            &args->nfs_server.hostname,
1916                                            PAGE_SIZE,
1917                                            &args->nfs_server.export_path,
1918                                            NFS_MAXPATHLEN);
1919                 if (!status)
1920                         status = nfs_try_mount(args, mntfh);
1921
1922                 kfree(args->nfs_server.export_path);
1923                 args->nfs_server.export_path = NULL;
1924
1925                 if (status)
1926                         return status;
1927
1928                 break;
1929                 }
1930         }
1931
1932 #ifndef CONFIG_NFS_V3
1933         if (args->version == 3)
1934                 goto out_v3_not_compiled;
1935 #endif /* !CONFIG_NFS_V3 */
1936
1937         return 0;
1938
1939 out_no_data:
1940         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1941         return -EINVAL;
1942
1943 out_no_v3:
1944         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1945                  data->version);
1946         return -EINVAL;
1947
1948 out_no_sec:
1949         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1950         return -EINVAL;
1951
1952 #ifndef CONFIG_NFS_V3
1953 out_v3_not_compiled:
1954         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1955         return -EPROTONOSUPPORT;
1956 #endif /* !CONFIG_NFS_V3 */
1957
1958 #ifndef CONFIG_NFS_V4
1959 out_v4_not_compiled:
1960         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
1961         return -EPROTONOSUPPORT;
1962 #endif /* !CONFIG_NFS_V4 */
1963
1964 out_nomem:
1965         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1966         return -ENOMEM;
1967
1968 out_no_address:
1969         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1970         return -EINVAL;
1971
1972 out_invalid_fh:
1973         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1974         return -EINVAL;
1975 }
1976
1977 static int
1978 nfs_compare_remount_data(struct nfs_server *nfss,
1979                          struct nfs_parsed_mount_data *data)
1980 {
1981         if (data->flags != nfss->flags ||
1982             data->rsize != nfss->rsize ||
1983             data->wsize != nfss->wsize ||
1984             data->retrans != nfss->client->cl_timeout->to_retries ||
1985             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1986             data->acregmin != nfss->acregmin / HZ ||
1987             data->acregmax != nfss->acregmax / HZ ||
1988             data->acdirmin != nfss->acdirmin / HZ ||
1989             data->acdirmax != nfss->acdirmax / HZ ||
1990             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1991             data->nfs_server.port != nfss->port ||
1992             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1993             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
1994                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
1995                 return -EINVAL;
1996
1997         return 0;
1998 }
1999
2000 static int
2001 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2002 {
2003         int error;
2004         struct nfs_server *nfss = sb->s_fs_info;
2005         struct nfs_parsed_mount_data *data;
2006         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2007         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2008         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2009
2010         /*
2011          * Userspace mount programs that send binary options generally send
2012          * them populated with default values. We have no way to know which
2013          * ones were explicitly specified. Fall back to legacy behavior and
2014          * just return success.
2015          */
2016         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2017             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2018                                            options->version <= 6))))
2019                 return 0;
2020
2021         data = kzalloc(sizeof(*data), GFP_KERNEL);
2022         if (data == NULL)
2023                 return -ENOMEM;
2024
2025         /* fill out struct with values from existing mount */
2026         data->flags = nfss->flags;
2027         data->rsize = nfss->rsize;
2028         data->wsize = nfss->wsize;
2029         data->retrans = nfss->client->cl_timeout->to_retries;
2030         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2031         data->acregmin = nfss->acregmin / HZ;
2032         data->acregmax = nfss->acregmax / HZ;
2033         data->acdirmin = nfss->acdirmin / HZ;
2034         data->acdirmax = nfss->acdirmax / HZ;
2035         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2036         data->nfs_server.port = nfss->port;
2037         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2038         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2039                 data->nfs_server.addrlen);
2040
2041         /* overwrite those values with any that were specified */
2042         error = nfs_parse_mount_options((char *)options, data);
2043         if (error < 0)
2044                 goto out;
2045
2046         /*
2047          * noac is a special case. It implies -o sync, but that's not
2048          * necessarily reflected in the mtab options. do_remount_sb
2049          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2050          * remount options, so we have to explicitly reset it.
2051          */
2052         if (data->flags & NFS_MOUNT_NOAC)
2053                 *flags |= MS_SYNCHRONOUS;
2054
2055         /* compare new mount options with old ones */
2056         error = nfs_compare_remount_data(nfss, data);
2057 out:
2058         kfree(data);
2059         return error;
2060 }
2061
2062 /*
2063  * Initialise the common bits of the superblock
2064  */
2065 static inline void nfs_initialise_sb(struct super_block *sb)
2066 {
2067         struct nfs_server *server = NFS_SB(sb);
2068
2069         sb->s_magic = NFS_SUPER_MAGIC;
2070
2071         /* We probably want something more informative here */
2072         snprintf(sb->s_id, sizeof(sb->s_id),
2073                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2074
2075         if (sb->s_blocksize == 0)
2076                 sb->s_blocksize = nfs_block_bits(server->wsize,
2077                                                  &sb->s_blocksize_bits);
2078
2079         sb->s_bdi = &server->backing_dev_info;
2080
2081         nfs_super_set_maxbytes(sb, server->maxfilesize);
2082 }
2083
2084 /*
2085  * Finish setting up an NFS2/3 superblock
2086  */
2087 static void nfs_fill_super(struct super_block *sb,
2088                            struct nfs_parsed_mount_data *data)
2089 {
2090         struct nfs_server *server = NFS_SB(sb);
2091
2092         sb->s_blocksize_bits = 0;
2093         sb->s_blocksize = 0;
2094         if (data->bsize)
2095                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2096
2097         if (server->nfs_client->rpc_ops->version == 3) {
2098                 /* The VFS shouldn't apply the umask to mode bits. We will do
2099                  * so ourselves when necessary.
2100                  */
2101                 sb->s_flags |= MS_POSIXACL;
2102                 sb->s_time_gran = 1;
2103         }
2104
2105         sb->s_op = &nfs_sops;
2106         nfs_initialise_sb(sb);
2107 }
2108
2109 /*
2110  * Finish setting up a cloned NFS2/3 superblock
2111  */
2112 static void nfs_clone_super(struct super_block *sb,
2113                             const struct super_block *old_sb)
2114 {
2115         struct nfs_server *server = NFS_SB(sb);
2116
2117         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2118         sb->s_blocksize = old_sb->s_blocksize;
2119         sb->s_maxbytes = old_sb->s_maxbytes;
2120
2121         if (server->nfs_client->rpc_ops->version == 3) {
2122                 /* The VFS shouldn't apply the umask to mode bits. We will do
2123                  * so ourselves when necessary.
2124                  */
2125                 sb->s_flags |= MS_POSIXACL;
2126                 sb->s_time_gran = 1;
2127         }
2128
2129         sb->s_op = old_sb->s_op;
2130         nfs_initialise_sb(sb);
2131 }
2132
2133 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2134 {
2135         const struct nfs_server *a = s->s_fs_info;
2136         const struct rpc_clnt *clnt_a = a->client;
2137         const struct rpc_clnt *clnt_b = b->client;
2138
2139         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2140                 goto Ebusy;
2141         if (a->nfs_client != b->nfs_client)
2142                 goto Ebusy;
2143         if (a->flags != b->flags)
2144                 goto Ebusy;
2145         if (a->wsize != b->wsize)
2146                 goto Ebusy;
2147         if (a->rsize != b->rsize)
2148                 goto Ebusy;
2149         if (a->acregmin != b->acregmin)
2150                 goto Ebusy;
2151         if (a->acregmax != b->acregmax)
2152                 goto Ebusy;
2153         if (a->acdirmin != b->acdirmin)
2154                 goto Ebusy;
2155         if (a->acdirmax != b->acdirmax)
2156                 goto Ebusy;
2157         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2158                 goto Ebusy;
2159         return 1;
2160 Ebusy:
2161         return 0;
2162 }
2163
2164 struct nfs_sb_mountdata {
2165         struct nfs_server *server;
2166         int mntflags;
2167 };
2168
2169 static int nfs_set_super(struct super_block *s, void *data)
2170 {
2171         struct nfs_sb_mountdata *sb_mntdata = data;
2172         struct nfs_server *server = sb_mntdata->server;
2173         int ret;
2174
2175         s->s_flags = sb_mntdata->mntflags;
2176         s->s_fs_info = server;
2177         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2178         ret = set_anon_super(s, server);
2179         if (ret == 0)
2180                 server->s_dev = s->s_dev;
2181         return ret;
2182 }
2183
2184 static int nfs_compare_super_address(struct nfs_server *server1,
2185                                      struct nfs_server *server2)
2186 {
2187         struct sockaddr *sap1, *sap2;
2188
2189         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2190         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2191
2192         if (sap1->sa_family != sap2->sa_family)
2193                 return 0;
2194
2195         switch (sap1->sa_family) {
2196         case AF_INET: {
2197                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2198                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2199                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2200                         return 0;
2201                 if (sin1->sin_port != sin2->sin_port)
2202                         return 0;
2203                 break;
2204         }
2205         case AF_INET6: {
2206                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2207                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2208                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2209                         return 0;
2210                 if (sin1->sin6_port != sin2->sin6_port)
2211                         return 0;
2212                 break;
2213         }
2214         default:
2215                 return 0;
2216         }
2217
2218         return 1;
2219 }
2220
2221 static int nfs_compare_super(struct super_block *sb, void *data)
2222 {
2223         struct nfs_sb_mountdata *sb_mntdata = data;
2224         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2225         int mntflags = sb_mntdata->mntflags;
2226
2227         if (!nfs_compare_super_address(old, server))
2228                 return 0;
2229         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2230         if (old->flags & NFS_MOUNT_UNSHARED)
2231                 return 0;
2232         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2233                 return 0;
2234         return nfs_compare_mount_options(sb, server, mntflags);
2235 }
2236
2237 static int nfs_bdi_register(struct nfs_server *server)
2238 {
2239         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2240 }
2241
2242 static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2243         int flags, const char *dev_name, void *raw_data)
2244 {
2245         struct nfs_server *server = NULL;
2246         struct super_block *s;
2247         struct nfs_parsed_mount_data *data;
2248         struct nfs_fh *mntfh;
2249         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2250         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2251         struct nfs_sb_mountdata sb_mntdata = {
2252                 .mntflags = flags,
2253         };
2254         int error;
2255
2256         data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
2257         mntfh = nfs_alloc_fhandle();
2258         if (data == NULL || mntfh == NULL)
2259                 goto out;
2260
2261         /* Validate the mount data */
2262         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2263         if (error < 0) {
2264                 mntroot = ERR_PTR(error);
2265                 goto out;
2266         }
2267
2268 #ifdef CONFIG_NFS_V4
2269         if (data->version == 4) {
2270                 mntroot = nfs4_try_mount(flags, dev_name, data);
2271                 goto out;
2272         }
2273 #endif  /* CONFIG_NFS_V4 */
2274
2275         /* Get a volume representation */
2276         server = nfs_create_server(data, mntfh);
2277         if (IS_ERR(server)) {
2278                 mntroot = ERR_CAST(server);
2279                 goto out;
2280         }
2281         sb_mntdata.server = server;
2282
2283         if (server->flags & NFS_MOUNT_UNSHARED)
2284                 compare_super = NULL;
2285
2286         /* -o noac implies -o sync */
2287         if (server->flags & NFS_MOUNT_NOAC)
2288                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2289
2290         /* Get a superblock - note that we may end up sharing one that already exists */
2291         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2292         if (IS_ERR(s)) {
2293                 mntroot = ERR_CAST(s);
2294                 goto out_err_nosb;
2295         }
2296
2297         if (s->s_fs_info != server) {
2298                 nfs_free_server(server);
2299                 server = NULL;
2300         } else {
2301                 error = nfs_bdi_register(server);
2302                 if (error) {
2303                         mntroot = ERR_PTR(error);
2304                         goto error_splat_bdi;
2305                 }
2306         }
2307
2308         if (!s->s_root) {
2309                 /* initial superblock/root creation */
2310                 nfs_fill_super(s, data);
2311                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2312         }
2313
2314         mntroot = nfs_get_root(s, mntfh, dev_name);
2315         if (IS_ERR(mntroot))
2316                 goto error_splat_super;
2317
2318         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2319         if (error)
2320                 goto error_splat_root;
2321
2322         s->s_flags |= MS_ACTIVE;
2323
2324 out:
2325         nfs_free_parsed_mount_data(data);
2326         nfs_free_fhandle(mntfh);
2327         return mntroot;
2328
2329 out_err_nosb:
2330         nfs_free_server(server);
2331         goto out;
2332
2333 error_splat_root:
2334         dput(mntroot);
2335         mntroot = ERR_PTR(error);
2336 error_splat_super:
2337         if (server && !s->s_root)
2338                 bdi_unregister(&server->backing_dev_info);
2339 error_splat_bdi:
2340         deactivate_locked_super(s);
2341         goto out;
2342 }
2343
2344 /*
2345  * Ensure that we unregister the bdi before kill_anon_super
2346  * releases the device name
2347  */
2348 static void nfs_put_super(struct super_block *s)
2349 {
2350         struct nfs_server *server = NFS_SB(s);
2351
2352         bdi_unregister(&server->backing_dev_info);
2353 }
2354
2355 /*
2356  * Destroy an NFS2/3 superblock
2357  */
2358 static void nfs_kill_super(struct super_block *s)
2359 {
2360         struct nfs_server *server = NFS_SB(s);
2361
2362         kill_anon_super(s);
2363         nfs_fscache_release_super_cookie(s);
2364         nfs_free_server(server);
2365 }
2366
2367 /*
2368  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2369  */
2370 static struct dentry *
2371 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2372                 const char *dev_name, void *raw_data)
2373 {
2374         struct nfs_clone_mount *data = raw_data;
2375         struct super_block *s;
2376         struct nfs_server *server;
2377         struct dentry *mntroot;
2378         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2379         struct nfs_sb_mountdata sb_mntdata = {
2380                 .mntflags = flags,
2381         };
2382         int error;
2383
2384         dprintk("--> nfs_xdev_mount()\n");
2385
2386         /* create a new volume representation */
2387         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2388         if (IS_ERR(server)) {
2389                 error = PTR_ERR(server);
2390                 goto out_err_noserver;
2391         }
2392         sb_mntdata.server = server;
2393
2394         if (server->flags & NFS_MOUNT_UNSHARED)
2395                 compare_super = NULL;
2396
2397         /* -o noac implies -o sync */
2398         if (server->flags & NFS_MOUNT_NOAC)
2399                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2400
2401         /* Get a superblock - note that we may end up sharing one that already exists */
2402         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2403         if (IS_ERR(s)) {
2404                 error = PTR_ERR(s);
2405                 goto out_err_nosb;
2406         }
2407
2408         if (s->s_fs_info != server) {
2409                 nfs_free_server(server);
2410                 server = NULL;
2411         } else {
2412                 error = nfs_bdi_register(server);
2413                 if (error)
2414                         goto error_splat_bdi;
2415         }
2416
2417         if (!s->s_root) {
2418                 /* initial superblock/root creation */
2419                 nfs_clone_super(s, data->sb);
2420                 nfs_fscache_get_super_cookie(s, NULL, data);
2421         }
2422
2423         mntroot = nfs_get_root(s, data->fh, dev_name);
2424         if (IS_ERR(mntroot)) {
2425                 error = PTR_ERR(mntroot);
2426                 goto error_splat_super;
2427         }
2428         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2429                 dput(mntroot);
2430                 error = -ESTALE;
2431                 goto error_splat_super;
2432         }
2433
2434         s->s_flags |= MS_ACTIVE;
2435
2436         /* clone any lsm security options from the parent to the new sb */
2437         security_sb_clone_mnt_opts(data->sb, s);
2438
2439         dprintk("<-- nfs_xdev_mount() = 0\n");
2440         return mntroot;
2441
2442 out_err_nosb:
2443         nfs_free_server(server);
2444 out_err_noserver:
2445         dprintk("<-- nfs_xdev_mount() = %d [error]\n", error);
2446         return ERR_PTR(error);
2447
2448 error_splat_super:
2449         if (server && !s->s_root)
2450                 bdi_unregister(&server->backing_dev_info);
2451 error_splat_bdi:
2452         deactivate_locked_super(s);
2453         dprintk("<-- nfs_xdev_mount() = %d [splat]\n", error);
2454         return ERR_PTR(error);
2455 }
2456
2457 #ifdef CONFIG_NFS_V4
2458
2459 /*
2460  * Finish setting up a cloned NFS4 superblock
2461  */
2462 static void nfs4_clone_super(struct super_block *sb,
2463                             const struct super_block *old_sb)
2464 {
2465         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2466         sb->s_blocksize = old_sb->s_blocksize;
2467         sb->s_maxbytes = old_sb->s_maxbytes;
2468         sb->s_time_gran = 1;
2469         sb->s_op = old_sb->s_op;
2470         /*
2471          * The VFS shouldn't apply the umask to mode bits. We will do
2472          * so ourselves when necessary.
2473          */
2474         sb->s_flags  |= MS_POSIXACL;
2475         sb->s_xattr  = old_sb->s_xattr;
2476         nfs_initialise_sb(sb);
2477 }
2478
2479 /*
2480  * Set up an NFS4 superblock
2481  */
2482 static void nfs4_fill_super(struct super_block *sb)
2483 {
2484         sb->s_time_gran = 1;
2485         sb->s_op = &nfs4_sops;
2486         /*
2487          * The VFS shouldn't apply the umask to mode bits. We will do
2488          * so ourselves when necessary.
2489          */
2490         sb->s_flags  |= MS_POSIXACL;
2491         sb->s_xattr = nfs4_xattr_handlers;
2492         nfs_initialise_sb(sb);
2493 }
2494
2495 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2496 {
2497         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2498                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2499 }
2500
2501 static int nfs4_validate_text_mount_data(void *options,
2502                                          struct nfs_parsed_mount_data *args,
2503                                          const char *dev_name)
2504 {
2505         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2506
2507         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2508
2509         nfs_validate_transport_protocol(args);
2510
2511         nfs4_validate_mount_flags(args);
2512
2513         if (args->version != 4) {
2514                 dfprintk(MOUNT,
2515                          "NFS4: Illegal mount version\n");
2516                 return -EINVAL;
2517         }
2518
2519         if (args->auth_flavor_len > 1) {
2520                 dfprintk(MOUNT,
2521                          "NFS4: Too many RPC auth flavours specified\n");
2522                 return -EINVAL;
2523         }
2524
2525         if (args->client_address == NULL) {
2526                 dfprintk(MOUNT,
2527                          "NFS4: mount program didn't pass callback address\n");
2528                 return -EINVAL;
2529         }
2530
2531         return nfs_parse_devname(dev_name,
2532                                    &args->nfs_server.hostname,
2533                                    NFS4_MAXNAMLEN,
2534                                    &args->nfs_server.export_path,
2535                                    NFS4_MAXPATHLEN);
2536 }
2537
2538 /*
2539  * Validate NFSv4 mount options
2540  */
2541 static int nfs4_validate_mount_data(void *options,
2542                                     struct nfs_parsed_mount_data *args,
2543                                     const char *dev_name)
2544 {
2545         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2546         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2547         char *c;
2548
2549         if (data == NULL)
2550                 goto out_no_data;
2551
2552         switch (data->version) {
2553         case 1:
2554                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2555                         goto out_no_address;
2556                 if (data->host_addrlen == 0)
2557                         goto out_no_address;
2558                 args->nfs_server.addrlen = data->host_addrlen;
2559                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2560                         return -EFAULT;
2561                 if (!nfs_verify_server_address(sap))
2562                         goto out_no_address;
2563
2564                 if (data->auth_flavourlen) {
2565                         if (data->auth_flavourlen > 1)
2566                                 goto out_inval_auth;
2567                         if (copy_from_user(&args->auth_flavors[0],
2568                                            data->auth_flavours,
2569                                            sizeof(args->auth_flavors[0])))
2570                                 return -EFAULT;
2571                 }
2572
2573                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2574                 if (IS_ERR(c))
2575                         return PTR_ERR(c);
2576                 args->nfs_server.hostname = c;
2577
2578                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2579                 if (IS_ERR(c))
2580                         return PTR_ERR(c);
2581                 args->nfs_server.export_path = c;
2582                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2583
2584                 c = strndup_user(data->client_addr.data, 16);
2585                 if (IS_ERR(c))
2586                         return PTR_ERR(c);
2587                 args->client_address = c;
2588
2589                 /*
2590                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2591                  * can deal with.
2592                  */
2593
2594                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2595                 args->rsize     = data->rsize;
2596                 args->wsize     = data->wsize;
2597                 args->timeo     = data->timeo;
2598                 args->retrans   = data->retrans;
2599                 args->acregmin  = data->acregmin;
2600                 args->acregmax  = data->acregmax;
2601                 args->acdirmin  = data->acdirmin;
2602                 args->acdirmax  = data->acdirmax;
2603                 args->nfs_server.protocol = data->proto;
2604                 nfs_validate_transport_protocol(args);
2605
2606                 break;
2607         default:
2608                 if (nfs_parse_mount_options((char *)options, args) == 0)
2609                         return -EINVAL;
2610
2611                 if (!nfs_verify_server_address(sap))
2612                         return -EINVAL;
2613
2614                 return nfs4_validate_text_mount_data(options, args, dev_name);
2615         }
2616
2617         return 0;
2618
2619 out_no_data:
2620         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2621         return -EINVAL;
2622
2623 out_inval_auth:
2624         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2625                  data->auth_flavourlen);
2626         return -EINVAL;
2627
2628 out_no_address:
2629         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2630         return -EINVAL;
2631 }
2632
2633 /*
2634  * Get the superblock for the NFS4 root partition
2635  */
2636 static struct dentry *
2637 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
2638                   const char *dev_name, void *raw_data)
2639 {
2640         struct nfs_parsed_mount_data *data = raw_data;
2641         struct super_block *s;
2642         struct nfs_server *server;
2643         struct nfs_fh *mntfh;
2644         struct dentry *mntroot;
2645         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2646         struct nfs_sb_mountdata sb_mntdata = {
2647                 .mntflags = flags,
2648         };
2649         int error = -ENOMEM;
2650
2651         mntfh = nfs_alloc_fhandle();
2652         if (data == NULL || mntfh == NULL)
2653                 goto out;
2654
2655         /* Get a volume representation */
2656         server = nfs4_create_server(data, mntfh);
2657         if (IS_ERR(server)) {
2658                 error = PTR_ERR(server);
2659                 goto out;
2660         }
2661         sb_mntdata.server = server;
2662
2663         if (server->flags & NFS4_MOUNT_UNSHARED)
2664                 compare_super = NULL;
2665
2666         /* -o noac implies -o sync */
2667         if (server->flags & NFS_MOUNT_NOAC)
2668                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2669
2670         /* Get a superblock - note that we may end up sharing one that already exists */
2671         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2672         if (IS_ERR(s)) {
2673                 error = PTR_ERR(s);
2674                 goto out_free;
2675         }
2676
2677         if (s->s_fs_info != server) {
2678                 nfs_free_server(server);
2679                 server = NULL;
2680         } else {
2681                 error = nfs_bdi_register(server);
2682                 if (error)
2683                         goto error_splat_bdi;
2684         }
2685
2686         if (!s->s_root) {
2687                 /* initial superblock/root creation */
2688                 nfs4_fill_super(s);
2689                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2690         }
2691
2692         mntroot = nfs4_get_root(s, mntfh, dev_name);
2693         if (IS_ERR(mntroot)) {
2694                 error = PTR_ERR(mntroot);
2695                 goto error_splat_super;
2696         }
2697
2698         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2699         if (error)
2700                 goto error_splat_root;
2701
2702         s->s_flags |= MS_ACTIVE;
2703
2704         nfs_free_fhandle(mntfh);
2705         return mntroot;
2706
2707 out:
2708         nfs_free_fhandle(mntfh);
2709         return ERR_PTR(error);
2710
2711 out_free:
2712         nfs_free_server(server);
2713         goto out;
2714
2715 error_splat_root:
2716         dput(mntroot);
2717 error_splat_super:
2718         if (server && !s->s_root)
2719                 bdi_unregister(&server->backing_dev_info);
2720 error_splat_bdi:
2721         deactivate_locked_super(s);
2722         goto out;
2723 }
2724
2725 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2726                 int flags, void *data, const char *hostname)
2727 {
2728         struct vfsmount *root_mnt;
2729         char *root_devname;
2730         size_t len;
2731
2732         len = strlen(hostname) + 3;
2733         root_devname = kmalloc(len, GFP_KERNEL);
2734         if (root_devname == NULL)
2735                 return ERR_PTR(-ENOMEM);
2736         snprintf(root_devname, len, "%s:/", hostname);
2737         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2738         kfree(root_devname);
2739         return root_mnt;
2740 }
2741
2742 struct nfs_referral_count {
2743         struct list_head list;
2744         const struct task_struct *task;
2745         unsigned int referral_count;
2746 };
2747
2748 static LIST_HEAD(nfs_referral_count_list);
2749 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2750
2751 static struct nfs_referral_count *nfs_find_referral_count(void)
2752 {
2753         struct nfs_referral_count *p;
2754
2755         list_for_each_entry(p, &nfs_referral_count_list, list) {
2756                 if (p->task == current)
2757                         return p;
2758         }
2759         return NULL;
2760 }
2761
2762 #define NFS_MAX_NESTED_REFERRALS 2
2763
2764 static int nfs_referral_loop_protect(void)
2765 {
2766         struct nfs_referral_count *p, *new;
2767         int ret = -ENOMEM;
2768
2769         new = kmalloc(sizeof(*new), GFP_KERNEL);
2770         if (!new)
2771                 goto out;
2772         new->task = current;
2773         new->referral_count = 1;
2774
2775         ret = 0;
2776         spin_lock(&nfs_referral_count_list_lock);
2777         p = nfs_find_referral_count();
2778         if (p != NULL) {
2779                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2780                         ret = -ELOOP;
2781                 else
2782                         p->referral_count++;
2783         } else {
2784                 list_add(&new->list, &nfs_referral_count_list);
2785                 new = NULL;
2786         }
2787         spin_unlock(&nfs_referral_count_list_lock);
2788         kfree(new);
2789 out:
2790         return ret;
2791 }
2792
2793 static void nfs_referral_loop_unprotect(void)
2794 {
2795         struct nfs_referral_count *p;
2796
2797         spin_lock(&nfs_referral_count_list_lock);
2798         p = nfs_find_referral_count();
2799         p->referral_count--;
2800         if (p->referral_count == 0)
2801                 list_del(&p->list);
2802         else
2803                 p = NULL;
2804         spin_unlock(&nfs_referral_count_list_lock);
2805         kfree(p);
2806 }
2807
2808 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
2809                 const char *export_path)
2810 {
2811         struct dentry *dentry;
2812         int err;
2813
2814         if (IS_ERR(root_mnt))
2815                 return ERR_CAST(root_mnt);
2816
2817         err = nfs_referral_loop_protect();
2818         if (err) {
2819                 mntput(root_mnt);
2820                 return ERR_PTR(err);
2821         }
2822
2823         dentry = mount_subtree(root_mnt, export_path);
2824         nfs_referral_loop_unprotect();
2825
2826         return dentry;
2827 }
2828
2829 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
2830                          struct nfs_parsed_mount_data *data)
2831 {
2832         char *export_path;
2833         struct vfsmount *root_mnt;
2834         struct dentry *res;
2835
2836         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2837
2838         export_path = data->nfs_server.export_path;
2839         data->nfs_server.export_path = "/";
2840         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2841                         data->nfs_server.hostname);
2842         data->nfs_server.export_path = export_path;
2843
2844         res = nfs_follow_remote_path(root_mnt, export_path);
2845
2846         dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
2847                         IS_ERR(res) ? PTR_ERR(res) : 0,
2848                         IS_ERR(res) ? " [error]" : "");
2849         return res;
2850 }
2851
2852 /*
2853  * Get the superblock for an NFS4 mountpoint
2854  */
2855 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
2856         int flags, const char *dev_name, void *raw_data)
2857 {
2858         struct nfs_parsed_mount_data *data;
2859         int error = -ENOMEM;
2860         struct dentry *res = ERR_PTR(-ENOMEM);
2861
2862         data = nfs_alloc_parsed_mount_data(4);
2863         if (data == NULL)
2864                 goto out;
2865
2866         /* Validate the mount data */
2867         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2868         if (error < 0) {
2869                 res = ERR_PTR(error);
2870                 goto out;
2871         }
2872
2873         res = nfs4_try_mount(flags, dev_name, data);
2874         if (IS_ERR(res))
2875                 error = PTR_ERR(res);
2876
2877 out:
2878         nfs_free_parsed_mount_data(data);
2879         dprintk("<-- nfs4_mount() = %d%s\n", error,
2880                         error != 0 ? " [error]" : "");
2881         return res;
2882 }
2883
2884 static void nfs4_kill_super(struct super_block *sb)
2885 {
2886         struct nfs_server *server = NFS_SB(sb);
2887
2888         dprintk("--> %s\n", __func__);
2889         nfs_super_return_all_delegations(sb);
2890         kill_anon_super(sb);
2891         nfs_fscache_release_super_cookie(sb);
2892         nfs_free_server(server);
2893         dprintk("<-- %s\n", __func__);
2894 }
2895
2896 /*
2897  * Clone an NFS4 server record on xdev traversal (FSID-change)
2898  */
2899 static struct dentry *
2900 nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
2901                  const char *dev_name, void *raw_data)
2902 {
2903         struct nfs_clone_mount *data = raw_data;
2904         struct super_block *s;
2905         struct nfs_server *server;
2906         struct dentry *mntroot;
2907         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2908         struct nfs_sb_mountdata sb_mntdata = {
2909                 .mntflags = flags,
2910         };
2911         int error;
2912
2913         dprintk("--> nfs4_xdev_mount()\n");
2914
2915         /* create a new volume representation */
2916         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2917         if (IS_ERR(server)) {
2918                 error = PTR_ERR(server);
2919                 goto out_err_noserver;
2920         }
2921         sb_mntdata.server = server;
2922
2923         if (server->flags & NFS4_MOUNT_UNSHARED)
2924                 compare_super = NULL;
2925
2926         /* -o noac implies -o sync */
2927         if (server->flags & NFS_MOUNT_NOAC)
2928                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2929
2930         /* Get a superblock - note that we may end up sharing one that already exists */
2931         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2932         if (IS_ERR(s)) {
2933                 error = PTR_ERR(s);
2934                 goto out_err_nosb;
2935         }
2936
2937         if (s->s_fs_info != server) {
2938                 nfs_free_server(server);
2939                 server = NULL;
2940         } else {
2941                 error = nfs_bdi_register(server);
2942                 if (error)
2943                         goto error_splat_bdi;
2944         }
2945
2946         if (!s->s_root) {
2947                 /* initial superblock/root creation */
2948                 nfs4_clone_super(s, data->sb);
2949                 nfs_fscache_get_super_cookie(s, NULL, data);
2950         }
2951
2952         mntroot = nfs4_get_root(s, data->fh, dev_name);
2953         if (IS_ERR(mntroot)) {
2954                 error = PTR_ERR(mntroot);
2955                 goto error_splat_super;
2956         }
2957         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2958                 dput(mntroot);
2959                 error = -ESTALE;
2960                 goto error_splat_super;
2961         }
2962
2963         s->s_flags |= MS_ACTIVE;
2964
2965         security_sb_clone_mnt_opts(data->sb, s);
2966
2967         dprintk("<-- nfs4_xdev_mount() = 0\n");
2968         return mntroot;
2969
2970 out_err_nosb:
2971         nfs_free_server(server);
2972 out_err_noserver:
2973         dprintk("<-- nfs4_xdev_mount() = %d [error]\n", error);
2974         return ERR_PTR(error);
2975
2976 error_splat_super:
2977         if (server && !s->s_root)
2978                 bdi_unregister(&server->backing_dev_info);
2979 error_splat_bdi:
2980         deactivate_locked_super(s);
2981         dprintk("<-- nfs4_xdev_mount() = %d [splat]\n", error);
2982         return ERR_PTR(error);
2983 }
2984
2985 static struct dentry *
2986 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
2987                            const char *dev_name, void *raw_data)
2988 {
2989         struct nfs_clone_mount *data = raw_data;
2990         struct super_block *s;
2991         struct nfs_server *server;
2992         struct dentry *mntroot;
2993         struct nfs_fh *mntfh;
2994         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2995         struct nfs_sb_mountdata sb_mntdata = {
2996                 .mntflags = flags,
2997         };
2998         int error = -ENOMEM;
2999
3000         dprintk("--> nfs4_referral_get_sb()\n");
3001
3002         mntfh = nfs_alloc_fhandle();
3003         if (mntfh == NULL)
3004                 goto out_err_nofh;
3005
3006         /* create a new volume representation */
3007         server = nfs4_create_referral_server(data, mntfh);
3008         if (IS_ERR(server)) {
3009                 error = PTR_ERR(server);
3010                 goto out_err_noserver;
3011         }
3012         sb_mntdata.server = server;
3013
3014         if (server->flags & NFS4_MOUNT_UNSHARED)
3015                 compare_super = NULL;
3016
3017         /* -o noac implies -o sync */
3018         if (server->flags & NFS_MOUNT_NOAC)
3019                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
3020
3021         /* Get a superblock - note that we may end up sharing one that already exists */
3022         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
3023         if (IS_ERR(s)) {
3024                 error = PTR_ERR(s);
3025                 goto out_err_nosb;
3026         }
3027
3028         if (s->s_fs_info != server) {
3029                 nfs_free_server(server);
3030                 server = NULL;
3031         } else {
3032                 error = nfs_bdi_register(server);
3033                 if (error)
3034                         goto error_splat_bdi;
3035         }
3036
3037         if (!s->s_root) {
3038                 /* initial superblock/root creation */
3039                 nfs4_fill_super(s);
3040                 nfs_fscache_get_super_cookie(s, NULL, data);
3041         }
3042
3043         mntroot = nfs4_get_root(s, mntfh, dev_name);
3044         if (IS_ERR(mntroot)) {
3045                 error = PTR_ERR(mntroot);
3046                 goto error_splat_super;
3047         }
3048         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3049                 dput(mntroot);
3050                 error = -ESTALE;
3051                 goto error_splat_super;
3052         }
3053
3054         s->s_flags |= MS_ACTIVE;
3055
3056         security_sb_clone_mnt_opts(data->sb, s);
3057
3058         nfs_free_fhandle(mntfh);
3059         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3060         return mntroot;
3061
3062 out_err_nosb:
3063         nfs_free_server(server);
3064 out_err_noserver:
3065         nfs_free_fhandle(mntfh);
3066 out_err_nofh:
3067         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3068         return ERR_PTR(error);
3069
3070 error_splat_super:
3071         if (server && !s->s_root)
3072                 bdi_unregister(&server->backing_dev_info);
3073 error_splat_bdi:
3074         deactivate_locked_super(s);
3075         nfs_free_fhandle(mntfh);
3076         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3077         return ERR_PTR(error);
3078 }
3079
3080 /*
3081  * Create an NFS4 server record on referral traversal
3082  */
3083 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
3084                 int flags, const char *dev_name, void *raw_data)
3085 {
3086         struct nfs_clone_mount *data = raw_data;
3087         char *export_path;
3088         struct vfsmount *root_mnt;
3089         struct dentry *res;
3090
3091         dprintk("--> nfs4_referral_mount()\n");
3092
3093         export_path = data->mnt_path;
3094         data->mnt_path = "/";
3095
3096         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3097                         flags, data, data->hostname);
3098         data->mnt_path = export_path;
3099
3100         res = nfs_follow_remote_path(root_mnt, export_path);
3101         dprintk("<-- nfs4_referral_mount() = %ld%s\n",
3102                         IS_ERR(res) ? PTR_ERR(res) : 0,
3103                         IS_ERR(res) ? " [error]" : "");
3104         return res;
3105 }
3106
3107 #endif /* CONFIG_NFS_V4 */