fs/nfs/super.c

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