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 <[email protected]>, 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  *  [email protected]
  13  *
  14  *  Split from inode.c by David Howells <[email protected]>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/seq_file.h>
  43 #include <linux/mount.h>
  44 #include <linux/namei.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56 #include <linux/rcupdate.h>
  57
  58 #include <asm/system.h>
  59 #include <asm/uaccess.h>
  60
  61 #include "nfs4_fs.h"
  62 #include "callback.h"
  63 #include "delegation.h"
  64 #include "iostat.h"
  65 #include "internal.h"
  66 #include "fscache.h"
  67 #include "pnfs.h"
  68
  69 #define NFSDBG_FACILITY         NFSDBG_VFS
  70
  71 #ifdef CONFIG_NFS_V3
  72 #define NFS_DEFAULT_VERSION 3
  73 #else
  74 #define NFS_DEFAULT_VERSION 2
  75 #endif
  76
  77 enum {
  78         /* Mount options that take no arguments */
  79         Opt_soft, Opt_hard,
  80         Opt_posix, Opt_noposix,
  81         Opt_cto, Opt_nocto,
  82         Opt_ac, Opt_noac,
  83         Opt_lock, Opt_nolock,
  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_minorversion,
 102
 103         /* Mount options that take string arguments */
 104         Opt_nfsvers,
 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_udp, "udp" },
 137         { Opt_tcp, "tcp" },
 138         { Opt_rdma, "rdma" },
 139         { Opt_acl, "acl" },
 140         { Opt_noacl, "noacl" },
 141         { Opt_rdirplus, "rdirplus" },
 142         { Opt_nordirplus, "nordirplus" },
 143         { Opt_sharecache, "sharecache" },
 144         { Opt_nosharecache, "nosharecache" },
 145         { Opt_resvport, "resvport" },
 146         { Opt_noresvport, "noresvport" },
 147         { Opt_fscache, "fsc" },
 148         { Opt_nofscache, "nofsc" },
 149
 150         { Opt_port, "port=%s" },
 151         { Opt_rsize, "rsize=%s" },
 152         { Opt_wsize, "wsize=%s" },
 153         { Opt_bsize, "bsize=%s" },
 154         { Opt_timeo, "timeo=%s" },
 155         { Opt_retrans, "retrans=%s" },
 156         { Opt_acregmin, "acregmin=%s" },
 157         { Opt_acregmax, "acregmax=%s" },
 158         { Opt_acdirmin, "acdirmin=%s" },
 159         { Opt_acdirmax, "acdirmax=%s" },
 160         { Opt_actimeo, "actimeo=%s" },
 161         { Opt_namelen, "namlen=%s" },
 162         { Opt_mountport, "mountport=%s" },
 163         { Opt_mountvers, "mountvers=%s" },
 164         { Opt_minorversion, "minorversion=%s" },
 165
 166         { Opt_nfsvers, "nfsvers=%s" },
 167         { Opt_nfsvers, "vers=%s" },
 168
 169         { Opt_sec, "sec=%s" },
 170         { Opt_proto, "proto=%s" },
 171         { Opt_mountproto, "mountproto=%s" },
 172         { Opt_addr, "addr=%s" },
 173         { Opt_clientaddr, "clientaddr=%s" },
 174         { Opt_mounthost, "mounthost=%s" },
 175         { Opt_mountaddr, "mountaddr=%s" },
 176
 177         { Opt_lookupcache, "lookupcache=%s" },
 178         { Opt_fscache_uniq, "fsc=%s" },
 179         { Opt_local_lock, "local_lock=%s" },
 180
 181         /* The following needs to be listed after all other options */
 182         { Opt_nfsvers, "v%s" },
 183
 184         { Opt_err, NULL }
 185 };
 186
 187 enum {
 188         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 189
 190         Opt_xprt_err
 191 };
 192
 193 static const match_table_t nfs_xprt_protocol_tokens = {
 194         { Opt_xprt_udp, "udp" },
 195         { Opt_xprt_udp6, "udp6" },
 196         { Opt_xprt_tcp, "tcp" },
 197         { Opt_xprt_tcp6, "tcp6" },
 198         { Opt_xprt_rdma, "rdma" },
 199
 200         { Opt_xprt_err, NULL }
 201 };
 202
 203 enum {
 204         Opt_sec_none, Opt_sec_sys,
 205         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 206         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 207         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 208
 209         Opt_sec_err
 210 };
 211
 212 static const match_table_t nfs_secflavor_tokens = {
 213         { Opt_sec_none, "none" },
 214         { Opt_sec_none, "null" },
 215         { Opt_sec_sys, "sys" },
 216
 217         { Opt_sec_krb5, "krb5" },
 218         { Opt_sec_krb5i, "krb5i" },
 219         { Opt_sec_krb5p, "krb5p" },
 220
 221         { Opt_sec_lkey, "lkey" },
 222         { Opt_sec_lkeyi, "lkeyi" },
 223         { Opt_sec_lkeyp, "lkeyp" },
 224
 225         { Opt_sec_spkm, "spkm3" },
 226         { Opt_sec_spkmi, "spkm3i" },
 227         { Opt_sec_spkmp, "spkm3p" },
 228
 229         { Opt_sec_err, NULL }
 230 };
 231
 232 enum {
 233         Opt_lookupcache_all, Opt_lookupcache_positive,
 234         Opt_lookupcache_none,
 235
 236         Opt_lookupcache_err
 237 };
 238
 239 static match_table_t nfs_lookupcache_tokens = {
 240         { Opt_lookupcache_all, "all" },
 241         { Opt_lookupcache_positive, "pos" },
 242         { Opt_lookupcache_positive, "positive" },
 243         { Opt_lookupcache_none, "none" },
 244
 245         { Opt_lookupcache_err, NULL }
 246 };
 247
 248 enum {
 249         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 250         Opt_local_lock_none,
 251
 252         Opt_local_lock_err
 253 };
 254
 255 static match_table_t nfs_local_lock_tokens = {
 256         { Opt_local_lock_all, "all" },
 257         { Opt_local_lock_flock, "flock" },
 258         { Opt_local_lock_posix, "posix" },
 259         { Opt_local_lock_none, "none" },
 260
 261         { Opt_local_lock_err, NULL }
 262 };
 263
 264 enum {
 265         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 266         Opt_vers_4_1,
 267
 268         Opt_vers_err
 269 };
 270
 271 static match_table_t nfs_vers_tokens = {
 272         { Opt_vers_2, "2" },
 273         { Opt_vers_3, "3" },
 274         { Opt_vers_4, "4" },
 275         { Opt_vers_4_0, "4.0" },
 276         { Opt_vers_4_1, "4.1" },
 277
 278         { Opt_vers_err, NULL }
 279 };
 280
 281 static void nfs_umount_begin(struct super_block *);
 282 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 283 static int  nfs_show_options(struct seq_file *, struct dentry *);
 284 static int  nfs_show_devname(struct seq_file *, struct dentry *);
 285 static int  nfs_show_path(struct seq_file *, struct dentry *);
 286 static int  nfs_show_stats(struct seq_file *, struct dentry *);
 287 static struct dentry *nfs_fs_mount(struct file_system_type *,
 288                 int, const char *, void *);
 289 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 290                 int flags, const char *dev_name, void *raw_data);
 291 static void nfs_put_super(struct super_block *);
 292 static void nfs_kill_super(struct super_block *);
 293 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 294
 295 static struct file_system_type nfs_fs_type = {
 296         .owner          = THIS_MODULE,
 297         .name           = "nfs",
 298         .mount          = nfs_fs_mount,
 299         .kill_sb        = nfs_kill_super,
 300         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 301 };
 302
 303 struct file_system_type nfs_xdev_fs_type = {
 304         .owner          = THIS_MODULE,
 305         .name           = "nfs",
 306         .mount          = nfs_xdev_mount,
 307         .kill_sb        = nfs_kill_super,
 308         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 309 };
 310
 311 static const struct super_operations nfs_sops = {
 312         .alloc_inode    = nfs_alloc_inode,
 313         .destroy_inode  = nfs_destroy_inode,
 314         .write_inode    = nfs_write_inode,
 315         .put_super      = nfs_put_super,
 316         .statfs         = nfs_statfs,
 317         .evict_inode    = nfs_evict_inode,
 318         .umount_begin   = nfs_umount_begin,
 319         .show_options   = nfs_show_options,
 320         .show_devname   = nfs_show_devname,
 321         .show_path      = nfs_show_path,
 322         .show_stats     = nfs_show_stats,
 323         .remount_fs     = nfs_remount,
 324 };
 325
 326 #ifdef CONFIG_NFS_V4
 327 static int nfs4_validate_text_mount_data(void *options,
 328         struct nfs_parsed_mount_data *args, const char *dev_name);
 329 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
 330         struct nfs_parsed_mount_data *data);
 331 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
 332         int flags, const char *dev_name, void *raw_data);
 333 static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
 334         int flags, const char *dev_name, void *raw_data);
 335 static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
 336         int flags, const char *dev_name, void *raw_data);
 337 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
 338         int flags, const char *dev_name, void *raw_data);
 339 static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
 340         int flags, const char *dev_name, void *raw_data);
 341 static void nfs4_kill_super(struct super_block *sb);
 342
 343 static struct file_system_type nfs4_fs_type = {
 344         .owner          = THIS_MODULE,
 345         .name           = "nfs4",
 346         .mount          = nfs4_mount,
 347         .kill_sb        = nfs4_kill_super,
 348         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 349 };
 350
 351 static struct file_system_type nfs4_remote_fs_type = {
 352         .owner          = THIS_MODULE,
 353         .name           = "nfs4",
 354         .mount          = nfs4_remote_mount,
 355         .kill_sb        = nfs4_kill_super,
 356         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 357 };
 358
 359 struct file_system_type nfs4_xdev_fs_type = {
 360         .owner          = THIS_MODULE,
 361         .name           = "nfs4",
 362         .mount          = nfs4_xdev_mount,
 363         .kill_sb        = nfs4_kill_super,
 364         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 365 };
 366
 367 static struct file_system_type nfs4_remote_referral_fs_type = {
 368         .owner          = THIS_MODULE,
 369         .name           = "nfs4",
 370         .mount          = nfs4_remote_referral_mount,
 371         .kill_sb        = nfs4_kill_super,
 372         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 373 };
 374
 375 struct file_system_type nfs4_referral_fs_type = {
 376         .owner          = THIS_MODULE,
 377         .name           = "nfs4",
 378         .mount          = nfs4_referral_mount,
 379         .kill_sb        = nfs4_kill_super,
 380         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 381 };
 382
 383 static const struct super_operations nfs4_sops = {
 384         .alloc_inode    = nfs_alloc_inode,
 385         .destroy_inode  = nfs_destroy_inode,
 386         .write_inode    = nfs_write_inode,
 387         .put_super      = nfs_put_super,
 388         .statfs         = nfs_statfs,
 389         .evict_inode    = nfs4_evict_inode,
 390         .umount_begin   = nfs_umount_begin,
 391         .show_options   = nfs_show_options,
 392         .show_devname   = nfs_show_devname,
 393         .show_path      = nfs_show_path,
 394         .show_stats     = nfs_show_stats,
 395         .remount_fs     = nfs_remount,
 396 };
 397 #endif
 398
 399 static struct shrinker acl_shrinker = {
 400         .shrink         = nfs_access_cache_shrinker,
 401         .seeks          = DEFAULT_SEEKS,
 402 };
 403
 404 /*
 405  * Register the NFS filesystems
 406  */
 407 int __init register_nfs_fs(void)
 408 {
 409         int ret;
 410
 411         ret = register_filesystem(&nfs_fs_type);
 412         if (ret < 0)
 413                 goto error_0;
 414
 415         ret = nfs_register_sysctl();
 416         if (ret < 0)
 417                 goto error_1;
 418 #ifdef CONFIG_NFS_V4
 419         ret = register_filesystem(&nfs4_fs_type);
 420         if (ret < 0)
 421                 goto error_2;
 422 #endif
 423         register_shrinker(&acl_shrinker);
 424         return 0;
 425
 426 #ifdef CONFIG_NFS_V4
 427 error_2:
 428         nfs_unregister_sysctl();
 429 #endif
 430 error_1:
 431         unregister_filesystem(&nfs_fs_type);
 432 error_0:
 433         return ret;
 434 }
 435
 436 /*
 437  * Unregister the NFS filesystems
 438  */
 439 void __exit unregister_nfs_fs(void)
 440 {
 441         unregister_shrinker(&acl_shrinker);
 442 #ifdef CONFIG_NFS_V4
 443         unregister_filesystem(&nfs4_fs_type);
 444 #endif
 445         nfs_unregister_sysctl();
 446         unregister_filesystem(&nfs_fs_type);
 447 }
 448
 449 void nfs_sb_active(struct super_block *sb)
 450 {
 451         struct nfs_server *server = NFS_SB(sb);
 452
 453         if (atomic_inc_return(&server->active) == 1)
 454                 atomic_inc(&sb->s_active);
 455 }
 456
 457 void nfs_sb_deactive(struct super_block *sb)
 458 {
 459         struct nfs_server *server = NFS_SB(sb);
 460
 461         if (atomic_dec_and_test(&server->active))
 462                 deactivate_super(sb);
 463 }
 464
 465 /*
 466  * Deliver file system statistics to userspace
 467  */
 468 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 469 {
 470         struct nfs_server *server = NFS_SB(dentry->d_sb);
 471         unsigned char blockbits;
 472         unsigned long blockres;
 473         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 474         struct nfs_fsstat res;
 475         int error = -ENOMEM;
 476
 477         res.fattr = nfs_alloc_fattr();
 478         if (res.fattr == NULL)
 479                 goto out_err;
 480
 481         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 482         if (unlikely(error == -ESTALE)) {
 483                 struct dentry *pd_dentry;
 484
 485                 pd_dentry = dget_parent(dentry);
 486                 if (pd_dentry != NULL) {
 487                         nfs_zap_caches(pd_dentry->d_inode);
 488                         dput(pd_dentry);
 489                 }
 490         }
 491         nfs_free_fattr(res.fattr);
 492         if (error < 0)
 493                 goto out_err;
 494
 495         buf->f_type = NFS_SUPER_MAGIC;
 496
 497         /*
 498          * Current versions of glibc do not correctly handle the
 499          * case where f_frsize != f_bsize.  Eventually we want to
 500          * report the value of wtmult in this field.
 501          */
 502         buf->f_frsize = dentry->d_sb->s_blocksize;
 503
 504         /*
 505          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 506          * are reported in units of f_frsize.  Linux hasn't had
 507          * an f_frsize field in its statfs struct until recently,
 508          * thus historically Linux's sys_statfs reports these
 509          * fields in units of f_bsize.
 510          */
 511         buf->f_bsize = dentry->d_sb->s_blocksize;
 512         blockbits = dentry->d_sb->s_blocksize_bits;
 513         blockres = (1 << blockbits) - 1;
 514         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 515         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 516         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 517
 518         buf->f_files = res.tfiles;
 519         buf->f_ffree = res.afiles;
 520
 521         buf->f_namelen = server->namelen;
 522
 523         return 0;
 524
 525  out_err:
 526         dprintk("%s: statfs error = %d\n", __func__, -error);
 527         return error;
 528 }
 529
 530 /*
 531  * Map the security flavour number to a name
 532  */
 533 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 534 {
 535         static const struct {
 536                 rpc_authflavor_t flavour;
 537                 const char *str;
 538         } sec_flavours[] = {
 539                 { RPC_AUTH_NULL, "null" },
 540                 { RPC_AUTH_UNIX, "sys" },
 541                 { RPC_AUTH_GSS_KRB5, "krb5" },
 542                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 543                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 544                 { RPC_AUTH_GSS_LKEY, "lkey" },
 545                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 546                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 547                 { RPC_AUTH_GSS_SPKM, "spkm" },
 548                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 549                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 550                 { UINT_MAX, "unknown" }
 551         };
 552         int i;
 553
 554         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 555                 if (sec_flavours[i].flavour == flavour)
 556                         break;
 557         }
 558         return sec_flavours[i].str;
 559 }
 560
 561 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 562                                   int showdefaults)
 563 {
 564         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 565
 566         seq_printf(m, ",mountproto=");
 567         switch (sap->sa_family) {
 568         case AF_INET:
 569                 switch (nfss->mountd_protocol) {
 570                 case IPPROTO_UDP:
 571                         seq_printf(m, RPCBIND_NETID_UDP);
 572                         break;
 573                 case IPPROTO_TCP:
 574                         seq_printf(m, RPCBIND_NETID_TCP);
 575                         break;
 576                 default:
 577                         if (showdefaults)
 578                                 seq_printf(m, "auto");
 579                 }
 580                 break;
 581         case AF_INET6:
 582                 switch (nfss->mountd_protocol) {
 583                 case IPPROTO_UDP:
 584                         seq_printf(m, RPCBIND_NETID_UDP6);
 585                         break;
 586                 case IPPROTO_TCP:
 587                         seq_printf(m, RPCBIND_NETID_TCP6);
 588                         break;
 589                 default:
 590                         if (showdefaults)
 591                                 seq_printf(m, "auto");
 592                 }
 593                 break;
 594         default:
 595                 if (showdefaults)
 596                         seq_printf(m, "auto");
 597         }
 598 }
 599
 600 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 601                                     int showdefaults)
 602 {
 603         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 604
 605         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 606                 return;
 607
 608         switch (sap->sa_family) {
 609         case AF_INET: {
 610                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 611                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 612                 break;
 613         }
 614         case AF_INET6: {
 615                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 616                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 617                 break;
 618         }
 619         default:
 620                 if (showdefaults)
 621                         seq_printf(m, ",mountaddr=unspecified");
 622         }
 623
 624         if (nfss->mountd_version || showdefaults)
 625                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 626         if ((nfss->mountd_port &&
 627                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 628                 showdefaults)
 629                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 630
 631         nfs_show_mountd_netid(m, nfss, showdefaults);
 632 }
 633
 634 #ifdef CONFIG_NFS_V4
 635 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 636                                     int showdefaults)
 637 {
 638         struct nfs_client *clp = nfss->nfs_client;
 639
 640         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 641 }
 642 #else
 643 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 644                                     int showdefaults)
 645 {
 646 }
 647 #endif
 648
 649 static void nfs_show_nfs_version(struct seq_file *m,
 650                 unsigned int version,
 651                 unsigned int minorversion)
 652 {
 653         seq_printf(m, ",vers=%u", version);
 654         if (version == 4)
 655                 seq_printf(m, ".%u", minorversion);
 656 }
 657
 658 /*
 659  * Describe the mount options in force on this server representation
 660  */
 661 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 662                                    int showdefaults)
 663 {
 664         static const struct proc_nfs_info {
 665                 int flag;
 666                 const char *str;
 667                 const char *nostr;
 668         } nfs_info[] = {
 669                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 670                 { NFS_MOUNT_POSIX, ",posix", "" },
 671                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 672                 { NFS_MOUNT_NOAC, ",noac", "" },
 673                 { NFS_MOUNT_NONLM, ",nolock", "" },
 674                 { NFS_MOUNT_NOACL, ",noacl", "" },
 675                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 676                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 677                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 678                 { 0, NULL, NULL }
 679         };
 680         const struct proc_nfs_info *nfs_infop;
 681         struct nfs_client *clp = nfss->nfs_client;
 682         u32 version = clp->rpc_ops->version;
 683         int local_flock, local_fcntl;
 684
 685         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 686         seq_printf(m, ",rsize=%u", nfss->rsize);
 687         seq_printf(m, ",wsize=%u", nfss->wsize);
 688         if (nfss->bsize != 0)
 689                 seq_printf(m, ",bsize=%u", nfss->bsize);
 690         seq_printf(m, ",namlen=%u", nfss->namelen);
 691         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 692                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 693         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 694                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 695         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 696                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 697         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 698                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 699         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 700                 if (nfss->flags & nfs_infop->flag)
 701                         seq_puts(m, nfs_infop->str);
 702                 else
 703                         seq_puts(m, nfs_infop->nostr);
 704         }
 705         rcu_read_lock();
 706         seq_printf(m, ",proto=%s",
 707                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 708         rcu_read_unlock();
 709         if (version == 4) {
 710                 if (nfss->port != NFS_PORT)
 711                         seq_printf(m, ",port=%u", nfss->port);
 712         } else
 713                 if (nfss->port)
 714                         seq_printf(m, ",port=%u", nfss->port);
 715
 716         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 717         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 718         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 719
 720         if (version != 4)
 721                 nfs_show_mountd_options(m, nfss, showdefaults);
 722         else
 723                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 724
 725         if (nfss->options & NFS_OPTION_FSCACHE)
 726                 seq_printf(m, ",fsc");
 727
 728         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 729                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 730                         seq_printf(m, ",lookupcache=none");
 731                 else
 732                         seq_printf(m, ",lookupcache=pos");
 733         }
 734
 735         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 736         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 737
 738         if (!local_flock && !local_fcntl)
 739                 seq_printf(m, ",local_lock=none");
 740         else if (local_flock && local_fcntl)
 741                 seq_printf(m, ",local_lock=all");
 742         else if (local_flock)
 743                 seq_printf(m, ",local_lock=flock");
 744         else
 745                 seq_printf(m, ",local_lock=posix");
 746 }
 747
 748 /*
 749  * Describe the mount options on this VFS mountpoint
 750  */
 751 static int nfs_show_options(struct seq_file *m, struct dentry *root)
 752 {
 753         struct nfs_server *nfss = NFS_SB(root->d_sb);
 754
 755         nfs_show_mount_options(m, nfss, 0);
 756
 757         rcu_read_lock();
 758         seq_printf(m, ",addr=%s",
 759                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 760                                                         RPC_DISPLAY_ADDR));
 761         rcu_read_unlock();
 762
 763         return 0;
 764 }
 765
 766 #ifdef CONFIG_NFS_V4
 767 #ifdef CONFIG_NFS_V4_1
 768 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 769 {
 770         if (nfs4_has_session(server->nfs_client))
 771                 seq_printf(m, ",sessions");
 772 }
 773 #else
 774 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 775 #endif
 776 #endif
 777
 778 #ifdef CONFIG_NFS_V4_1
 779 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 780 {
 781         seq_printf(m, ",pnfs=");
 782         if (server->pnfs_curr_ld)
 783                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 784         else
 785                 seq_printf(m, "not configured");
 786 }
 787
 788 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 789 {
 790         if (nfss->nfs_client && nfss->nfs_client->impl_id) {
 791                 struct nfs41_impl_id *impl_id = nfss->nfs_client->impl_id;
 792                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 793                            "date='%llu,%u'",
 794                            impl_id->name, impl_id->domain,
 795                            impl_id->date.seconds, impl_id->date.nseconds);
 796         }
 797 }
 798 #else
 799 #ifdef CONFIG_NFS_V4
 800 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 801 {
 802 }
 803 #endif
 804 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 805 {
 806 }
 807 #endif
 808
 809 static int nfs_show_devname(struct seq_file *m, struct dentry *root)
 810 {
 811         char *page = (char *) __get_free_page(GFP_KERNEL);
 812         char *devname, *dummy;
 813         int err = 0;
 814         if (!page)
 815                 return -ENOMEM;
 816         devname = nfs_path(&dummy, root, page, PAGE_SIZE);
 817         if (IS_ERR(devname))
 818                 err = PTR_ERR(devname);
 819         else
 820                 seq_escape(m, devname, " \t\n\\");
 821         free_page((unsigned long)page);
 822         return err;
 823 }
 824
 825 static int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 826 {
 827         seq_puts(m, "/");
 828         return 0;
 829 }
 830
 831 /*
 832  * Present statistical information for this VFS mountpoint
 833  */
 834 static int nfs_show_stats(struct seq_file *m, struct dentry *root)
 835 {
 836         int i, cpu;
 837         struct nfs_server *nfss = NFS_SB(root->d_sb);
 838         struct rpc_auth *auth = nfss->client->cl_auth;
 839         struct nfs_iostats totals = { };
 840
 841         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 842
 843         /*
 844          * Display all mount option settings
 845          */
 846         seq_printf(m, "\n\topts:\t");
 847         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 848         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 849         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 850         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 851         nfs_show_mount_options(m, nfss, 1);
 852
 853         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 854
 855         show_implementation_id(m, nfss);
 856
 857         seq_printf(m, "\n\tcaps:\t");
 858         seq_printf(m, "caps=0x%x", nfss->caps);
 859         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 860         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 861         seq_printf(m, ",bsize=%u", nfss->bsize);
 862         seq_printf(m, ",namlen=%u", nfss->namelen);
 863
 864 #ifdef CONFIG_NFS_V4
 865         if (nfss->nfs_client->rpc_ops->version == 4) {
 866                 seq_printf(m, "\n\tnfsv4:\t");
 867                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 868                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 869                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 870                 show_sessions(m, nfss);
 871                 show_pnfs(m, nfss);
 872         }
 873 #endif
 874
 875         /*
 876          * Display security flavor in effect for this mount
 877          */
 878         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 879         if (auth->au_flavor)
 880                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 881
 882         /*
 883          * Display superblock I/O counters
 884          */
 885         for_each_possible_cpu(cpu) {
 886                 struct nfs_iostats *stats;
 887
 888                 preempt_disable();
 889                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 890
 891                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 892                         totals.events[i] += stats->events[i];
 893                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 894                         totals.bytes[i] += stats->bytes[i];
 895 #ifdef CONFIG_NFS_FSCACHE
 896                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 897                         totals.fscache[i] += stats->fscache[i];
 898 #endif
 899
 900                 preempt_enable();
 901         }
 902
 903         seq_printf(m, "\n\tevents:\t");
 904         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 905                 seq_printf(m, "%lu ", totals.events[i]);
 906         seq_printf(m, "\n\tbytes:\t");
 907         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 908                 seq_printf(m, "%Lu ", totals.bytes[i]);
 909 #ifdef CONFIG_NFS_FSCACHE
 910         if (nfss->options & NFS_OPTION_FSCACHE) {
 911                 seq_printf(m, "\n\tfsc:\t");
 912                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 913                         seq_printf(m, "%Lu ", totals.bytes[i]);
 914         }
 915 #endif
 916         seq_printf(m, "\n");
 917
 918         rpc_print_iostats(m, nfss->client);
 919
 920         return 0;
 921 }
 922
 923 /*
 924  * Begin unmount by attempting to remove all automounted mountpoints we added
 925  * in response to xdev traversals and referrals
 926  */
 927 static void nfs_umount_begin(struct super_block *sb)
 928 {
 929         struct nfs_server *server;
 930         struct rpc_clnt *rpc;
 931
 932         server = NFS_SB(sb);
 933         /* -EIO all pending I/O */
 934         rpc = server->client_acl;
 935         if (!IS_ERR(rpc))
 936                 rpc_killall_tasks(rpc);
 937         rpc = server->client;
 938         if (!IS_ERR(rpc))
 939                 rpc_killall_tasks(rpc);
 940 }
 941
 942 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
 943 {
 944         struct nfs_parsed_mount_data *data;
 945
 946         data = kzalloc(sizeof(*data), GFP_KERNEL);
 947         if (data) {
 948                 data->acregmin          = NFS_DEF_ACREGMIN;
 949                 data->acregmax          = NFS_DEF_ACREGMAX;
 950                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 951                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 952                 data->mount_server.port = NFS_UNSPEC_PORT;
 953                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 954                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 955                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 956                 data->auth_flavor_len   = 1;
 957                 data->version           = version;
 958                 data->minorversion      = 0;
 959                 data->net               = current->nsproxy->net_ns;
 960                 security_init_mnt_opts(&data->lsm_opts);
 961         }
 962         return data;
 963 }
 964
 965 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 966 {
 967         if (data) {
 968                 kfree(data->client_address);
 969                 kfree(data->mount_server.hostname);
 970                 kfree(data->nfs_server.export_path);
 971                 kfree(data->nfs_server.hostname);
 972                 kfree(data->fscache_uniq);
 973                 security_free_mnt_opts(&data->lsm_opts);
 974                 kfree(data);
 975         }
 976 }
 977
 978 /*
 979  * Sanity-check a server address provided by the mount command.
 980  *
 981  * Address family must be initialized, and address must not be
 982  * the ANY address for that family.
 983  */
 984 static int nfs_verify_server_address(struct sockaddr *addr)
 985 {
 986         switch (addr->sa_family) {
 987         case AF_INET: {
 988                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 989                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 990         }
 991         case AF_INET6: {
 992                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 993                 return !ipv6_addr_any(sa);
 994         }
 995         }
 996
 997         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 998         return 0;
 999 }
1000
1001 /*
1002  * Select between a default port value and a user-specified port value.
1003  * If a zero value is set, then autobind will be used.
1004  */
1005 static void nfs_set_port(struct sockaddr *sap, int *port,
1006                                  const unsigned short default_port)
1007 {
1008         if (*port == NFS_UNSPEC_PORT)
1009                 *port = default_port;
1010
1011         rpc_set_port(sap, *port);
1012 }
1013
1014 /*
1015  * Sanity check the NFS transport protocol.
1016  *
1017  */
1018 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
1019 {
1020         switch (mnt->nfs_server.protocol) {
1021         case XPRT_TRANSPORT_UDP:
1022         case XPRT_TRANSPORT_TCP:
1023         case XPRT_TRANSPORT_RDMA:
1024                 break;
1025         default:
1026                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1027         }
1028 }
1029
1030 /*
1031  * For text based NFSv2/v3 mounts, the mount protocol transport default
1032  * settings should depend upon the specified NFS transport.
1033  */
1034 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1035 {
1036         nfs_validate_transport_protocol(mnt);
1037
1038         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1039             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1040                         return;
1041         switch (mnt->nfs_server.protocol) {
1042         case XPRT_TRANSPORT_UDP:
1043                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1044                 break;
1045         case XPRT_TRANSPORT_TCP:
1046         case XPRT_TRANSPORT_RDMA:
1047                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1048         }
1049 }
1050
1051 /*
1052  * Parse the value of the 'sec=' option.
1053  */
1054 static int nfs_parse_security_flavors(char *value,
1055                                       struct nfs_parsed_mount_data *mnt)
1056 {
1057         substring_t args[MAX_OPT_ARGS];
1058
1059         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1060
1061         switch (match_token(value, nfs_secflavor_tokens, args)) {
1062         case Opt_sec_none:
1063                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1064                 break;
1065         case Opt_sec_sys:
1066                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1067                 break;
1068         case Opt_sec_krb5:
1069                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1070                 break;
1071         case Opt_sec_krb5i:
1072                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1073                 break;
1074         case Opt_sec_krb5p:
1075                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1076                 break;
1077         case Opt_sec_lkey:
1078                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1079                 break;
1080         case Opt_sec_lkeyi:
1081                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1082                 break;
1083         case Opt_sec_lkeyp:
1084                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1085                 break;
1086         case Opt_sec_spkm:
1087                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1088                 break;
1089         case Opt_sec_spkmi:
1090                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1091                 break;
1092         case Opt_sec_spkmp:
1093                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1094                 break;
1095         default:
1096                 return 0;
1097         }
1098
1099         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1100         mnt->auth_flavor_len = 1;
1101         return 1;
1102 }
1103
1104 static int nfs_parse_version_string(char *string,
1105                 struct nfs_parsed_mount_data *mnt,
1106                 substring_t *args)
1107 {
1108         mnt->flags &= ~NFS_MOUNT_VER3;
1109         switch (match_token(string, nfs_vers_tokens, args)) {
1110         case Opt_vers_2:
1111                 mnt->version = 2;
1112                 break;
1113         case Opt_vers_3:
1114                 mnt->flags |= NFS_MOUNT_VER3;
1115                 mnt->version = 3;
1116                 break;
1117         case Opt_vers_4:
1118                 /* Backward compatibility option. In future,
1119                  * the mount program should always supply
1120                  * a NFSv4 minor version number.
1121                  */
1122                 mnt->version = 4;
1123                 break;
1124         case Opt_vers_4_0:
1125                 mnt->version = 4;
1126                 mnt->minorversion = 0;
1127                 break;
1128         case Opt_vers_4_1:
1129                 mnt->version = 4;
1130                 mnt->minorversion = 1;
1131                 break;
1132         default:
1133                 return 0;
1134         }
1135         return 1;
1136 }
1137
1138 static int nfs_get_option_str(substring_t args[], char **option)
1139 {
1140         kfree(*option);
1141         *option = match_strdup(args);
1142         return !option;
1143 }
1144
1145 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1146 {
1147         int rc;
1148         char *string;
1149
1150         string = match_strdup(args);
1151         if (string == NULL)
1152                 return -ENOMEM;
1153         rc = strict_strtoul(string, 10, option);
1154         kfree(string);
1155
1156         return rc;
1157 }
1158
1159 /*
1160  * Error-check and convert a string of mount options from user space into
1161  * a data structure.  The whole mount string is processed; bad options are
1162  * skipped as they are encountered.  If there were no errors, return 1;
1163  * otherwise return 0 (zero).
1164  */
1165 static int nfs_parse_mount_options(char *raw,
1166                                    struct nfs_parsed_mount_data *mnt)
1167 {
1168         char *p, *string, *secdata;
1169         int rc, sloppy = 0, invalid_option = 0;
1170         unsigned short protofamily = AF_UNSPEC;
1171         unsigned short mountfamily = AF_UNSPEC;
1172
1173         if (!raw) {
1174                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1175                 return 1;
1176         }
1177         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1178
1179         secdata = alloc_secdata();
1180         if (!secdata)
1181                 goto out_nomem;
1182
1183         rc = security_sb_copy_data(raw, secdata);
1184         if (rc)
1185                 goto out_security_failure;
1186
1187         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1188         if (rc)
1189                 goto out_security_failure;
1190
1191         free_secdata(secdata);
1192
1193         while ((p = strsep(&raw, ",")) != NULL) {
1194                 substring_t args[MAX_OPT_ARGS];
1195                 unsigned long option;
1196                 int token;
1197
1198                 if (!*p)
1199                         continue;
1200
1201                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1202
1203                 token = match_token(p, nfs_mount_option_tokens, args);
1204                 switch (token) {
1205
1206                 /*
1207                  * boolean options:  foo/nofoo
1208                  */
1209                 case Opt_soft:
1210                         mnt->flags |= NFS_MOUNT_SOFT;
1211                         break;
1212                 case Opt_hard:
1213                         mnt->flags &= ~NFS_MOUNT_SOFT;
1214                         break;
1215                 case Opt_posix:
1216                         mnt->flags |= NFS_MOUNT_POSIX;
1217                         break;
1218                 case Opt_noposix:
1219                         mnt->flags &= ~NFS_MOUNT_POSIX;
1220                         break;
1221                 case Opt_cto:
1222                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1223                         break;
1224                 case Opt_nocto:
1225                         mnt->flags |= NFS_MOUNT_NOCTO;
1226                         break;
1227                 case Opt_ac:
1228                         mnt->flags &= ~NFS_MOUNT_NOAC;
1229                         break;
1230                 case Opt_noac:
1231                         mnt->flags |= NFS_MOUNT_NOAC;
1232                         break;
1233                 case Opt_lock:
1234                         mnt->flags &= ~NFS_MOUNT_NONLM;
1235                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1236                                         NFS_MOUNT_LOCAL_FCNTL);
1237                         break;
1238                 case Opt_nolock:
1239                         mnt->flags |= NFS_MOUNT_NONLM;
1240                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1241                                        NFS_MOUNT_LOCAL_FCNTL);
1242                         break;
1243                 case Opt_udp:
1244                         mnt->flags &= ~NFS_MOUNT_TCP;
1245                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1246                         break;
1247                 case Opt_tcp:
1248                         mnt->flags |= NFS_MOUNT_TCP;
1249                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1250                         break;
1251                 case Opt_rdma:
1252                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1253                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1254                         xprt_load_transport(p);
1255                         break;
1256                 case Opt_acl:
1257                         mnt->flags &= ~NFS_MOUNT_NOACL;
1258                         break;
1259                 case Opt_noacl:
1260                         mnt->flags |= NFS_MOUNT_NOACL;
1261                         break;
1262                 case Opt_rdirplus:
1263                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1264                         break;
1265                 case Opt_nordirplus:
1266                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1267                         break;
1268                 case Opt_sharecache:
1269                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1270                         break;
1271                 case Opt_nosharecache:
1272                         mnt->flags |= NFS_MOUNT_UNSHARED;
1273                         break;
1274                 case Opt_resvport:
1275                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1276                         break;
1277                 case Opt_noresvport:
1278                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1279                         break;
1280                 case Opt_fscache:
1281                         mnt->options |= NFS_OPTION_FSCACHE;
1282                         kfree(mnt->fscache_uniq);
1283                         mnt->fscache_uniq = NULL;
1284                         break;
1285                 case Opt_nofscache:
1286                         mnt->options &= ~NFS_OPTION_FSCACHE;
1287                         kfree(mnt->fscache_uniq);
1288                         mnt->fscache_uniq = NULL;
1289                         break;
1290
1291                 /*
1292                  * options that take numeric values
1293                  */
1294                 case Opt_port:
1295                         if (nfs_get_option_ul(args, &option) ||
1296                             option > USHRT_MAX)
1297                                 goto out_invalid_value;
1298                         mnt->nfs_server.port = option;
1299                         break;
1300                 case Opt_rsize:
1301                         if (nfs_get_option_ul(args, &option))
1302                                 goto out_invalid_value;
1303                         mnt->rsize = option;
1304                         break;
1305                 case Opt_wsize:
1306                         if (nfs_get_option_ul(args, &option))
1307                                 goto out_invalid_value;
1308                         mnt->wsize = option;
1309                         break;
1310                 case Opt_bsize:
1311                         if (nfs_get_option_ul(args, &option))
1312                                 goto out_invalid_value;
1313                         mnt->bsize = option;
1314                         break;
1315                 case Opt_timeo:
1316                         if (nfs_get_option_ul(args, &option) || option == 0)
1317                                 goto out_invalid_value;
1318                         mnt->timeo = option;
1319                         break;
1320                 case Opt_retrans:
1321                         if (nfs_get_option_ul(args, &option) || option == 0)
1322                                 goto out_invalid_value;
1323                         mnt->retrans = option;
1324                         break;
1325                 case Opt_acregmin:
1326                         if (nfs_get_option_ul(args, &option))
1327                                 goto out_invalid_value;
1328                         mnt->acregmin = option;
1329                         break;
1330                 case Opt_acregmax:
1331                         if (nfs_get_option_ul(args, &option))
1332                                 goto out_invalid_value;
1333                         mnt->acregmax = option;
1334                         break;
1335                 case Opt_acdirmin:
1336                         if (nfs_get_option_ul(args, &option))
1337                                 goto out_invalid_value;
1338                         mnt->acdirmin = option;
1339                         break;
1340                 case Opt_acdirmax:
1341                         if (nfs_get_option_ul(args, &option))
1342                                 goto out_invalid_value;
1343                         mnt->acdirmax = option;
1344                         break;
1345                 case Opt_actimeo:
1346                         if (nfs_get_option_ul(args, &option))
1347                                 goto out_invalid_value;
1348                         mnt->acregmin = mnt->acregmax =
1349                         mnt->acdirmin = mnt->acdirmax = option;
1350                         break;
1351                 case Opt_namelen:
1352                         if (nfs_get_option_ul(args, &option))
1353                                 goto out_invalid_value;
1354                         mnt->namlen = option;
1355                         break;
1356                 case Opt_mountport:
1357                         if (nfs_get_option_ul(args, &option) ||
1358                             option > USHRT_MAX)
1359                                 goto out_invalid_value;
1360                         mnt->mount_server.port = option;
1361                         break;
1362                 case Opt_mountvers:
1363                         if (nfs_get_option_ul(args, &option) ||
1364                             option < NFS_MNT_VERSION ||
1365                             option > NFS_MNT3_VERSION)
1366                                 goto out_invalid_value;
1367                         mnt->mount_server.version = option;
1368                         break;
1369                 case Opt_minorversion:
1370                         if (nfs_get_option_ul(args, &option))
1371                                 goto out_invalid_value;
1372                         if (option > NFS4_MAX_MINOR_VERSION)
1373                                 goto out_invalid_value;
1374                         mnt->minorversion = option;
1375                         break;
1376
1377                 /*
1378                  * options that take text values
1379                  */
1380                 case Opt_nfsvers:
1381                         string = match_strdup(args);
1382                         if (string == NULL)
1383                                 goto out_nomem;
1384                         rc = nfs_parse_version_string(string, mnt, args);
1385                         kfree(string);
1386                         if (!rc)
1387                                 goto out_invalid_value;
1388                         break;
1389                 case Opt_sec:
1390                         string = match_strdup(args);
1391                         if (string == NULL)
1392                                 goto out_nomem;
1393                         rc = nfs_parse_security_flavors(string, mnt);
1394                         kfree(string);
1395                         if (!rc) {
1396                                 dfprintk(MOUNT, "NFS:   unrecognized "
1397                                                 "security flavor\n");
1398                                 return 0;
1399                         }
1400                         break;
1401                 case Opt_proto:
1402                         string = match_strdup(args);
1403                         if (string == NULL)
1404                                 goto out_nomem;
1405                         token = match_token(string,
1406                                             nfs_xprt_protocol_tokens, args);
1407
1408                         protofamily = AF_INET;
1409                         switch (token) {
1410                         case Opt_xprt_udp6:
1411                                 protofamily = AF_INET6;
1412                         case Opt_xprt_udp:
1413                                 mnt->flags &= ~NFS_MOUNT_TCP;
1414                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1415                                 break;
1416                         case Opt_xprt_tcp6:
1417                                 protofamily = AF_INET6;
1418                         case Opt_xprt_tcp:
1419                                 mnt->flags |= NFS_MOUNT_TCP;
1420                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1421                                 break;
1422                         case Opt_xprt_rdma:
1423                                 /* vector side protocols to TCP */
1424                                 mnt->flags |= NFS_MOUNT_TCP;
1425                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1426                                 xprt_load_transport(string);
1427                                 break;
1428                         default:
1429                                 dfprintk(MOUNT, "NFS:   unrecognized "
1430                                                 "transport protocol\n");
1431                                 kfree(string);
1432                                 return 0;
1433                         }
1434                         kfree(string);
1435                         break;
1436                 case Opt_mountproto:
1437                         string = match_strdup(args);
1438                         if (string == NULL)
1439                                 goto out_nomem;
1440                         token = match_token(string,
1441                                             nfs_xprt_protocol_tokens, args);
1442                         kfree(string);
1443
1444                         mountfamily = AF_INET;
1445                         switch (token) {
1446                         case Opt_xprt_udp6:
1447                                 mountfamily = AF_INET6;
1448                         case Opt_xprt_udp:
1449                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1450                                 break;
1451                         case Opt_xprt_tcp6:
1452                                 mountfamily = AF_INET6;
1453                         case Opt_xprt_tcp:
1454                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1455                                 break;
1456                         case Opt_xprt_rdma: /* not used for side protocols */
1457                         default:
1458                                 dfprintk(MOUNT, "NFS:   unrecognized "
1459                                                 "transport protocol\n");
1460                                 return 0;
1461                         }
1462                         break;
1463                 case Opt_addr:
1464                         string = match_strdup(args);
1465                         if (string == NULL)
1466                                 goto out_nomem;
1467                         mnt->nfs_server.addrlen =
1468                                 rpc_pton(mnt->net, string, strlen(string),
1469                                         (struct sockaddr *)
1470                                         &mnt->nfs_server.address,
1471                                         sizeof(mnt->nfs_server.address));
1472                         kfree(string);
1473                         if (mnt->nfs_server.addrlen == 0)
1474                                 goto out_invalid_address;
1475                         break;
1476                 case Opt_clientaddr:
1477                         if (nfs_get_option_str(args, &mnt->client_address))
1478                                 goto out_nomem;
1479                         break;
1480                 case Opt_mounthost:
1481                         if (nfs_get_option_str(args,
1482                                                &mnt->mount_server.hostname))
1483                                 goto out_nomem;
1484                         break;
1485                 case Opt_mountaddr:
1486                         string = match_strdup(args);
1487                         if (string == NULL)
1488                                 goto out_nomem;
1489                         mnt->mount_server.addrlen =
1490                                 rpc_pton(mnt->net, string, strlen(string),
1491                                         (struct sockaddr *)
1492                                         &mnt->mount_server.address,
1493                                         sizeof(mnt->mount_server.address));
1494                         kfree(string);
1495                         if (mnt->mount_server.addrlen == 0)
1496                                 goto out_invalid_address;
1497                         break;
1498                 case Opt_lookupcache:
1499                         string = match_strdup(args);
1500                         if (string == NULL)
1501                                 goto out_nomem;
1502                         token = match_token(string,
1503                                         nfs_lookupcache_tokens, args);
1504                         kfree(string);
1505                         switch (token) {
1506                                 case Opt_lookupcache_all:
1507                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1508                                         break;
1509                                 case Opt_lookupcache_positive:
1510                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1511                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1512                                         break;
1513                                 case Opt_lookupcache_none:
1514                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1515                                         break;
1516                                 default:
1517                                         dfprintk(MOUNT, "NFS:   invalid "
1518                                                         "lookupcache argument\n");
1519                                         return 0;
1520                         };
1521                         break;
1522                 case Opt_fscache_uniq:
1523                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1524                                 goto out_nomem;
1525                         mnt->options |= NFS_OPTION_FSCACHE;
1526                         break;
1527                 case Opt_local_lock:
1528                         string = match_strdup(args);
1529                         if (string == NULL)
1530                                 goto out_nomem;
1531                         token = match_token(string, nfs_local_lock_tokens,
1532                                         args);
1533                         kfree(string);
1534                         switch (token) {
1535                         case Opt_local_lock_all:
1536                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1537                                                NFS_MOUNT_LOCAL_FCNTL);
1538                                 break;
1539                         case Opt_local_lock_flock:
1540                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1541                                 break;
1542                         case Opt_local_lock_posix:
1543                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1544                                 break;
1545                         case Opt_local_lock_none:
1546                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1547                                                 NFS_MOUNT_LOCAL_FCNTL);
1548                                 break;
1549                         default:
1550                                 dfprintk(MOUNT, "NFS:   invalid "
1551                                                 "local_lock argument\n");
1552                                 return 0;
1553                         };
1554                         break;
1555
1556                 /*
1557                  * Special options
1558                  */
1559                 case Opt_sloppy:
1560                         sloppy = 1;
1561                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1562                         break;
1563                 case Opt_userspace:
1564                 case Opt_deprecated:
1565                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1566                                         "'%s'\n", p);
1567                         break;
1568
1569                 default:
1570                         invalid_option = 1;
1571                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1572                                         "'%s'\n", p);
1573                 }
1574         }
1575
1576         if (!sloppy && invalid_option)
1577                 return 0;
1578
1579         if (mnt->minorversion && mnt->version != 4)
1580                 goto out_minorversion_mismatch;
1581
1582         /*
1583          * verify that any proto=/mountproto= options match the address
1584          * familiies in the addr=/mountaddr= options.
1585          */
1586         if (protofamily != AF_UNSPEC &&
1587             protofamily != mnt->nfs_server.address.ss_family)
1588                 goto out_proto_mismatch;
1589
1590         if (mountfamily != AF_UNSPEC) {
1591                 if (mnt->mount_server.addrlen) {
1592                         if (mountfamily != mnt->mount_server.address.ss_family)
1593                                 goto out_mountproto_mismatch;
1594                 } else {
1595                         if (mountfamily != mnt->nfs_server.address.ss_family)
1596                                 goto out_mountproto_mismatch;
1597                 }
1598         }
1599
1600         return 1;
1601
1602 out_mountproto_mismatch:
1603         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1604                          "option\n");
1605         return 0;
1606 out_proto_mismatch:
1607         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1608         return 0;
1609 out_invalid_address:
1610         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1611         return 0;
1612 out_invalid_value:
1613         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1614         return 0;
1615 out_minorversion_mismatch:
1616         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1617                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1618         return 0;
1619 out_nomem:
1620         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1621         return 0;
1622 out_security_failure:
1623         free_secdata(secdata);
1624         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1625         return 0;
1626 }
1627
1628 /*
1629  * Match the requested auth flavors with the list returned by
1630  * the server.  Returns zero and sets the mount's authentication
1631  * flavor on success; returns -EACCES if server does not support
1632  * the requested flavor.
1633  */
1634 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1635                              struct nfs_mount_request *request)
1636 {
1637         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1638
1639         /*
1640          * Certain releases of Linux's mountd return an empty
1641          * flavor list.  To prevent behavioral regression with
1642          * these servers (ie. rejecting mounts that used to
1643          * succeed), revert to pre-2.6.32 behavior (no checking)
1644          * if the returned flavor list is empty.
1645          */
1646         if (server_authlist_len == 0)
1647                 return 0;
1648
1649         /*
1650          * We avoid sophisticated negotiating here, as there are
1651          * plenty of cases where we can get it wrong, providing
1652          * either too little or too much security.
1653          *
1654          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1655          * flavor listed first.  However, some servers list
1656          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1657          * preferred default, in args->auth_flavors[0] if user
1658          * didn't specify sec= mount option.
1659          */
1660         for (i = 0; i < args->auth_flavor_len; i++)
1661                 for (j = 0; j < server_authlist_len; j++)
1662                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1663                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1664                                         request->auth_flavs[j]);
1665                                 args->auth_flavors[0] = request->auth_flavs[j];
1666                                 return 0;
1667                         }
1668
1669         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1670         nfs_umount(request);
1671         return -EACCES;
1672 }
1673
1674 /*
1675  * Use the remote server's MOUNT service to request the NFS file handle
1676  * corresponding to the provided path.
1677  */
1678 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1679                          struct nfs_fh *root_fh)
1680 {
1681         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1682         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1683         struct nfs_mount_request request = {
1684                 .sap            = (struct sockaddr *)
1685                                                 &args->mount_server.address,
1686                 .dirpath        = args->nfs_server.export_path,
1687                 .protocol       = args->mount_server.protocol,
1688                 .fh             = root_fh,
1689                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1690                 .auth_flav_len  = &server_authlist_len,
1691                 .auth_flavs     = server_authlist,
1692                 .net            = args->net,
1693         };
1694         int status;
1695
1696         if (args->mount_server.version == 0) {
1697                 switch (args->version) {
1698                         default:
1699                                 args->mount_server.version = NFS_MNT3_VERSION;
1700                                 break;
1701                         case 2:
1702                                 args->mount_server.version = NFS_MNT_VERSION;
1703                 }
1704         }
1705         request.version = args->mount_server.version;
1706
1707         if (args->mount_server.hostname)
1708                 request.hostname = args->mount_server.hostname;
1709         else
1710                 request.hostname = args->nfs_server.hostname;
1711
1712         /*
1713          * Construct the mount server's address.
1714          */
1715         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1716                 memcpy(request.sap, &args->nfs_server.address,
1717                        args->nfs_server.addrlen);
1718                 args->mount_server.addrlen = args->nfs_server.addrlen;
1719         }
1720         request.salen = args->mount_server.addrlen;
1721         nfs_set_port(request.sap, &args->mount_server.port, 0);
1722
1723         /*
1724          * Now ask the mount server to map our export path
1725          * to a file handle.
1726          */
1727         status = nfs_mount(&request);
1728         if (status != 0) {
1729                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1730                                 request.hostname, status);
1731                 return status;
1732         }
1733
1734         /*
1735          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1736          */
1737         if (args->mount_server.version != NFS_MNT3_VERSION)
1738                 return 0;
1739         return nfs_walk_authlist(args, &request);
1740 }
1741
1742 /*
1743  * Split "dev_name" into "hostname:export_path".
1744  *
1745  * The leftmost colon demarks the split between the server's hostname
1746  * and the export path.  If the hostname starts with a left square
1747  * bracket, then it may contain colons.
1748  *
1749  * Note: caller frees hostname and export path, even on error.
1750  */
1751 static int nfs_parse_devname(const char *dev_name,
1752                              char **hostname, size_t maxnamlen,
1753                              char **export_path, size_t maxpathlen)
1754 {
1755         size_t len;
1756         char *end;
1757
1758         /* Is the host name protected with square brakcets? */
1759         if (*dev_name == '[') {
1760                 end = strchr(++dev_name, ']');
1761                 if (end == NULL || end[1] != ':')
1762                         goto out_bad_devname;
1763
1764                 len = end - dev_name;
1765                 end++;
1766         } else {
1767                 char *comma;
1768
1769                 end = strchr(dev_name, ':');
1770                 if (end == NULL)
1771                         goto out_bad_devname;
1772                 len = end - dev_name;
1773
1774                 /* kill possible hostname list: not supported */
1775                 comma = strchr(dev_name, ',');
1776                 if (comma != NULL && comma < end)
1777                         *comma = 0;
1778         }
1779
1780         if (len > maxnamlen)
1781                 goto out_hostname;
1782
1783         /* N.B. caller will free nfs_server.hostname in all cases */
1784         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1785         if (*hostname == NULL)
1786                 goto out_nomem;
1787         len = strlen(++end);
1788         if (len > maxpathlen)
1789                 goto out_path;
1790         *export_path = kstrndup(end, len, GFP_KERNEL);
1791         if (!*export_path)
1792                 goto out_nomem;
1793
1794         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1795         return 0;
1796
1797 out_bad_devname:
1798         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1799         return -EINVAL;
1800
1801 out_nomem:
1802         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1803         return -ENOMEM;
1804
1805 out_hostname:
1806         dfprintk(MOUNT, "NFS: server hostname too long\n");
1807         return -ENAMETOOLONG;
1808
1809 out_path:
1810         dfprintk(MOUNT, "NFS: export pathname too long\n");
1811         return -ENAMETOOLONG;
1812 }
1813
1814 /*
1815  * Validate the NFS2/NFS3 mount data
1816  * - fills in the mount root filehandle
1817  *
1818  * For option strings, user space handles the following behaviors:
1819  *
1820  * + DNS: mapping server host name to IP address ("addr=" option)
1821  *
1822  * + failure mode: how to behave if a mount request can't be handled
1823  *   immediately ("fg/bg" option)
1824  *
1825  * + retry: how often to retry a mount request ("retry=" option)
1826  *
1827  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1828  *   mountproto=tcp after mountproto=udp, and so on
1829  */
1830 static int nfs_validate_mount_data(void *options,
1831                                    struct nfs_parsed_mount_data *args,
1832                                    struct nfs_fh *mntfh,
1833                                    const char *dev_name)
1834 {
1835         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1836         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1837
1838         if (data == NULL)
1839                 goto out_no_data;
1840
1841         switch (data->version) {
1842         case 1:
1843                 data->namlen = 0;
1844         case 2:
1845                 data->bsize = 0;
1846         case 3:
1847                 if (data->flags & NFS_MOUNT_VER3)
1848                         goto out_no_v3;
1849                 data->root.size = NFS2_FHSIZE;
1850                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1851         case 4:
1852                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1853                         goto out_no_sec;
1854         case 5:
1855                 memset(data->context, 0, sizeof(data->context));
1856         case 6:
1857                 if (data->flags & NFS_MOUNT_VER3) {
1858                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1859                                 goto out_invalid_fh;
1860                         mntfh->size = data->root.size;
1861                         args->version = 3;
1862                 } else {
1863                         mntfh->size = NFS2_FHSIZE;
1864                         args->version = 2;
1865                 }
1866
1867
1868                 memcpy(mntfh->data, data->root.data, mntfh->size);
1869                 if (mntfh->size < sizeof(mntfh->data))
1870                         memset(mntfh->data + mntfh->size, 0,
1871                                sizeof(mntfh->data) - mntfh->size);
1872
1873                 /*
1874                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1875                  * can deal with.
1876                  */
1877                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1878                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1879                 args->rsize             = data->rsize;
1880                 args->wsize             = data->wsize;
1881                 args->timeo             = data->timeo;
1882                 args->retrans           = data->retrans;
1883                 args->acregmin          = data->acregmin;
1884                 args->acregmax          = data->acregmax;
1885                 args->acdirmin          = data->acdirmin;
1886                 args->acdirmax          = data->acdirmax;
1887
1888                 memcpy(sap, &data->addr, sizeof(data->addr));
1889                 args->nfs_server.addrlen = sizeof(data->addr);
1890                 if (!nfs_verify_server_address(sap))
1891                         goto out_no_address;
1892
1893                 if (!(data->flags & NFS_MOUNT_TCP))
1894                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1895                 /* N.B. caller will free nfs_server.hostname in all cases */
1896                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1897                 args->namlen            = data->namlen;
1898                 args->bsize             = data->bsize;
1899
1900                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1901                         args->auth_flavors[0] = data->pseudoflavor;
1902                 if (!args->nfs_server.hostname)
1903                         goto out_nomem;
1904
1905                 if (!(data->flags & NFS_MOUNT_NONLM))
1906                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1907                                          NFS_MOUNT_LOCAL_FCNTL);
1908                 else
1909                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1910                                         NFS_MOUNT_LOCAL_FCNTL);
1911                 /*
1912                  * The legacy version 6 binary mount data from userspace has a
1913                  * field used only to transport selinux information into the
1914                  * the kernel.  To continue to support that functionality we
1915                  * have a touch of selinux knowledge here in the NFS code. The
1916                  * userspace code converted context=blah to just blah so we are
1917                  * converting back to the full string selinux understands.
1918                  */
1919                 if (data->context[0]){
1920 #ifdef CONFIG_SECURITY_SELINUX
1921                         int rc;
1922                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1923                         if (!opts_str)
1924                                 return -ENOMEM;
1925                         strcpy(opts_str, "context=");
1926                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1927                         strcat(opts_str, &data->context[0]);
1928                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1929                         kfree(opts_str);
1930                         if (rc)
1931                                 return rc;
1932 #else
1933                         return -EINVAL;
1934 #endif
1935                 }
1936
1937                 break;
1938         default: {
1939                 int status;
1940
1941                 if (nfs_parse_mount_options((char *)options, args) == 0)
1942                         return -EINVAL;
1943
1944                 if (!nfs_verify_server_address(sap))
1945                         goto out_no_address;
1946
1947                 if (args->version == 4)
1948 #ifdef CONFIG_NFS_V4
1949                         return nfs4_validate_text_mount_data(options,
1950                                                              args, dev_name);
1951 #else
1952                         goto out_v4_not_compiled;
1953 #endif
1954
1955                 nfs_set_port(sap, &args->nfs_server.port, 0);
1956
1957                 nfs_set_mount_transport_protocol(args);
1958
1959                 status = nfs_parse_devname(dev_name,
1960                                            &args->nfs_server.hostname,
1961                                            PAGE_SIZE,
1962                                            &args->nfs_server.export_path,
1963                                            NFS_MAXPATHLEN);
1964                 if (!status)
1965                         status = nfs_try_mount(args, mntfh);
1966
1967                 kfree(args->nfs_server.export_path);
1968                 args->nfs_server.export_path = NULL;
1969
1970                 if (status)
1971                         return status;
1972
1973                 break;
1974                 }
1975         }
1976
1977 #ifndef CONFIG_NFS_V3
1978         if (args->version == 3)
1979                 goto out_v3_not_compiled;
1980 #endif /* !CONFIG_NFS_V3 */
1981
1982         return 0;
1983
1984 out_no_data:
1985         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1986         return -EINVAL;
1987
1988 out_no_v3:
1989         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1990                  data->version);
1991         return -EINVAL;
1992
1993 out_no_sec:
1994         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1995         return -EINVAL;
1996
1997 #ifndef CONFIG_NFS_V3
1998 out_v3_not_compiled:
1999         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2000         return -EPROTONOSUPPORT;
2001 #endif /* !CONFIG_NFS_V3 */
2002
2003 #ifndef CONFIG_NFS_V4
2004 out_v4_not_compiled:
2005         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2006         return -EPROTONOSUPPORT;
2007 #endif /* !CONFIG_NFS_V4 */
2008
2009 out_nomem:
2010         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2011         return -ENOMEM;
2012
2013 out_no_address:
2014         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2015         return -EINVAL;
2016
2017 out_invalid_fh:
2018         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2019         return -EINVAL;
2020 }
2021
2022 static int
2023 nfs_compare_remount_data(struct nfs_server *nfss,
2024                          struct nfs_parsed_mount_data *data)
2025 {
2026         if (data->flags != nfss->flags ||
2027             data->rsize != nfss->rsize ||
2028             data->wsize != nfss->wsize ||
2029             data->retrans != nfss->client->cl_timeout->to_retries ||
2030             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2031             data->acregmin != nfss->acregmin / HZ ||
2032             data->acregmax != nfss->acregmax / HZ ||
2033             data->acdirmin != nfss->acdirmin / HZ ||
2034             data->acdirmax != nfss->acdirmax / HZ ||
2035             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2036             data->nfs_server.port != nfss->port ||
2037             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2038             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2039                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2040                 return -EINVAL;
2041
2042         return 0;
2043 }
2044
2045 static int
2046 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2047 {
2048         int error;
2049         struct nfs_server *nfss = sb->s_fs_info;
2050         struct nfs_parsed_mount_data *data;
2051         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2052         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2053         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2054
2055         /*
2056          * Userspace mount programs that send binary options generally send
2057          * them populated with default values. We have no way to know which
2058          * ones were explicitly specified. Fall back to legacy behavior and
2059          * just return success.
2060          */
2061         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2062             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2063                                            options->version <= 6))))
2064                 return 0;
2065
2066         data = kzalloc(sizeof(*data), GFP_KERNEL);
2067         if (data == NULL)
2068                 return -ENOMEM;
2069
2070         /* fill out struct with values from existing mount */
2071         data->flags = nfss->flags;
2072         data->rsize = nfss->rsize;
2073         data->wsize = nfss->wsize;
2074         data->retrans = nfss->client->cl_timeout->to_retries;
2075         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2076         data->acregmin = nfss->acregmin / HZ;
2077         data->acregmax = nfss->acregmax / HZ;
2078         data->acdirmin = nfss->acdirmin / HZ;
2079         data->acdirmax = nfss->acdirmax / HZ;
2080         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2081         data->nfs_server.port = nfss->port;
2082         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2083         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2084                 data->nfs_server.addrlen);
2085
2086         /* overwrite those values with any that were specified */
2087         error = nfs_parse_mount_options((char *)options, data);
2088         if (error < 0)
2089                 goto out;
2090
2091         /*
2092          * noac is a special case. It implies -o sync, but that's not
2093          * necessarily reflected in the mtab options. do_remount_sb
2094          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2095          * remount options, so we have to explicitly reset it.
2096          */
2097         if (data->flags & NFS_MOUNT_NOAC)
2098                 *flags |= MS_SYNCHRONOUS;
2099
2100         /* compare new mount options with old ones */
2101         error = nfs_compare_remount_data(nfss, data);
2102 out:
2103         kfree(data);
2104         return error;
2105 }
2106
2107 /*
2108  * Initialise the common bits of the superblock
2109  */
2110 static inline void nfs_initialise_sb(struct super_block *sb)
2111 {
2112         struct nfs_server *server = NFS_SB(sb);
2113
2114         sb->s_magic = NFS_SUPER_MAGIC;
2115
2116         /* We probably want something more informative here */
2117         snprintf(sb->s_id, sizeof(sb->s_id),
2118                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2119
2120         if (sb->s_blocksize == 0)
2121                 sb->s_blocksize = nfs_block_bits(server->wsize,
2122                                                  &sb->s_blocksize_bits);
2123
2124         sb->s_bdi = &server->backing_dev_info;
2125
2126         nfs_super_set_maxbytes(sb, server->maxfilesize);
2127 }
2128
2129 /*
2130  * Finish setting up an NFS2/3 superblock
2131  */
2132 static void nfs_fill_super(struct super_block *sb,
2133                            struct nfs_parsed_mount_data *data)
2134 {
2135         struct nfs_server *server = NFS_SB(sb);
2136
2137         sb->s_blocksize_bits = 0;
2138         sb->s_blocksize = 0;
2139         if (data->bsize)
2140                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2141
2142         if (server->nfs_client->rpc_ops->version == 3) {
2143                 /* The VFS shouldn't apply the umask to mode bits. We will do
2144                  * so ourselves when necessary.
2145                  */
2146                 sb->s_flags |= MS_POSIXACL;
2147                 sb->s_time_gran = 1;
2148         }
2149
2150         sb->s_op = &nfs_sops;
2151         nfs_initialise_sb(sb);
2152 }
2153
2154 /*
2155  * Finish setting up a cloned NFS2/3 superblock
2156  */
2157 static void nfs_clone_super(struct super_block *sb,
2158                             const struct super_block *old_sb)
2159 {
2160         struct nfs_server *server = NFS_SB(sb);
2161
2162         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2163         sb->s_blocksize = old_sb->s_blocksize;
2164         sb->s_maxbytes = old_sb->s_maxbytes;
2165
2166         if (server->nfs_client->rpc_ops->version == 3) {
2167                 /* The VFS shouldn't apply the umask to mode bits. We will do
2168                  * so ourselves when necessary.
2169                  */
2170                 sb->s_flags |= MS_POSIXACL;
2171                 sb->s_time_gran = 1;
2172         }
2173
2174         sb->s_op = old_sb->s_op;
2175         nfs_initialise_sb(sb);
2176 }
2177
2178 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2179 {
2180         const struct nfs_server *a = s->s_fs_info;
2181         const struct rpc_clnt *clnt_a = a->client;
2182         const struct rpc_clnt *clnt_b = b->client;
2183
2184         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2185                 goto Ebusy;
2186         if (a->nfs_client != b->nfs_client)
2187                 goto Ebusy;
2188         if (a->flags != b->flags)
2189                 goto Ebusy;
2190         if (a->wsize != b->wsize)
2191                 goto Ebusy;
2192         if (a->rsize != b->rsize)
2193                 goto Ebusy;
2194         if (a->acregmin != b->acregmin)
2195                 goto Ebusy;
2196         if (a->acregmax != b->acregmax)
2197                 goto Ebusy;
2198         if (a->acdirmin != b->acdirmin)
2199                 goto Ebusy;
2200         if (a->acdirmax != b->acdirmax)
2201                 goto Ebusy;
2202         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2203                 goto Ebusy;
2204         return 1;
2205 Ebusy:
2206         return 0;
2207 }
2208
2209 struct nfs_sb_mountdata {
2210         struct nfs_server *server;
2211         int mntflags;
2212 };
2213
2214 static int nfs_set_super(struct super_block *s, void *data)
2215 {
2216         struct nfs_sb_mountdata *sb_mntdata = data;
2217         struct nfs_server *server = sb_mntdata->server;
2218         int ret;
2219
2220         s->s_flags = sb_mntdata->mntflags;
2221         s->s_fs_info = server;
2222         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2223         ret = set_anon_super(s, server);
2224         if (ret == 0)
2225                 server->s_dev = s->s_dev;
2226         return ret;
2227 }
2228
2229 static int nfs_compare_super_address(struct nfs_server *server1,
2230                                      struct nfs_server *server2)
2231 {
2232         struct sockaddr *sap1, *sap2;
2233
2234         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2235         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2236
2237         if (sap1->sa_family != sap2->sa_family)
2238                 return 0;
2239
2240         switch (sap1->sa_family) {
2241         case AF_INET: {
2242                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2243                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2244                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2245                         return 0;
2246                 if (sin1->sin_port != sin2->sin_port)
2247                         return 0;
2248                 break;
2249         }
2250         case AF_INET6: {
2251                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2252                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2253                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2254                         return 0;
2255                 if (sin1->sin6_port != sin2->sin6_port)
2256                         return 0;
2257                 break;
2258         }
2259         default:
2260                 return 0;
2261         }
2262
2263         return 1;
2264 }
2265
2266 static int nfs_compare_super(struct super_block *sb, void *data)
2267 {
2268         struct nfs_sb_mountdata *sb_mntdata = data;
2269         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2270         int mntflags = sb_mntdata->mntflags;
2271
2272         if (!nfs_compare_super_address(old, server))
2273                 return 0;
2274         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2275         if (old->flags & NFS_MOUNT_UNSHARED)
2276                 return 0;
2277         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2278                 return 0;
2279         return nfs_compare_mount_options(sb, server, mntflags);
2280 }
2281
2282 static int nfs_bdi_register(struct nfs_server *server)
2283 {
2284         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2285 }
2286
2287 static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2288         int flags, const char *dev_name, void *raw_data)
2289 {
2290         struct nfs_server *server = NULL;
2291         struct super_block *s;
2292         struct nfs_parsed_mount_data *data;
2293         struct nfs_fh *mntfh;
2294         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2295         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2296         struct nfs_sb_mountdata sb_mntdata = {
2297                 .mntflags = flags,
2298         };
2299         int error;
2300
2301         data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
2302         mntfh = nfs_alloc_fhandle();
2303         if (data == NULL || mntfh == NULL)
2304                 goto out;
2305
2306         /* Validate the mount data */
2307         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
2308         if (error < 0) {
2309                 mntroot = ERR_PTR(error);
2310                 goto out;
2311         }
2312
2313 #ifdef CONFIG_NFS_V4
2314         if (data->version == 4) {
2315                 mntroot = nfs4_try_mount(flags, dev_name, data);
2316                 goto out;
2317         }
2318 #endif  /* CONFIG_NFS_V4 */
2319
2320         /* Get a volume representation */
2321         server = nfs_create_server(data, mntfh);
2322         if (IS_ERR(server)) {
2323                 mntroot = ERR_CAST(server);
2324                 goto out;
2325         }
2326         sb_mntdata.server = server;
2327
2328         if (server->flags & NFS_MOUNT_UNSHARED)
2329                 compare_super = NULL;
2330
2331         /* -o noac implies -o sync */
2332         if (server->flags & NFS_MOUNT_NOAC)
2333                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2334
2335         /* Get a superblock - note that we may end up sharing one that already exists */
2336         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2337         if (IS_ERR(s)) {
2338                 mntroot = ERR_CAST(s);
2339                 goto out_err_nosb;
2340         }
2341
2342         if (s->s_fs_info != server) {
2343                 nfs_free_server(server);
2344                 server = NULL;
2345         } else {
2346                 error = nfs_bdi_register(server);
2347                 if (error) {
2348                         mntroot = ERR_PTR(error);
2349                         goto error_splat_bdi;
2350                 }
2351         }
2352
2353         if (!s->s_root) {
2354                 /* initial superblock/root creation */
2355                 nfs_fill_super(s, data);
2356                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2357         }
2358
2359         mntroot = nfs_get_root(s, mntfh, dev_name);
2360         if (IS_ERR(mntroot))
2361                 goto error_splat_super;
2362
2363         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2364         if (error)
2365                 goto error_splat_root;
2366
2367         s->s_flags |= MS_ACTIVE;
2368
2369 out:
2370         nfs_free_parsed_mount_data(data);
2371         nfs_free_fhandle(mntfh);
2372         return mntroot;
2373
2374 out_err_nosb:
2375         nfs_free_server(server);
2376         goto out;
2377
2378 error_splat_root:
2379         dput(mntroot);
2380         mntroot = ERR_PTR(error);
2381 error_splat_super:
2382         if (server && !s->s_root)
2383                 bdi_unregister(&server->backing_dev_info);
2384 error_splat_bdi:
2385         deactivate_locked_super(s);
2386         goto out;
2387 }
2388
2389 /*
2390  * Ensure that we unregister the bdi before kill_anon_super
2391  * releases the device name
2392  */
2393 static void nfs_put_super(struct super_block *s)
2394 {
2395         struct nfs_server *server = NFS_SB(s);
2396
2397         bdi_unregister(&server->backing_dev_info);
2398 }
2399
2400 /*
2401  * Destroy an NFS2/3 superblock
2402  */
2403 static void nfs_kill_super(struct super_block *s)
2404 {
2405         struct nfs_server *server = NFS_SB(s);
2406
2407         kill_anon_super(s);
2408         nfs_fscache_release_super_cookie(s);
2409         nfs_free_server(server);
2410 }
2411
2412 /*
2413  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
2414  */
2415 static struct dentry *
2416 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2417                 const char *dev_name, void *raw_data)
2418 {
2419         struct nfs_clone_mount *data = raw_data;
2420         struct super_block *s;
2421         struct nfs_server *server;
2422         struct dentry *mntroot;
2423         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2424         struct nfs_sb_mountdata sb_mntdata = {
2425                 .mntflags = flags,
2426         };
2427         int error;
2428
2429         dprintk("--> nfs_xdev_mount()\n");
2430
2431         /* create a new volume representation */
2432         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2433         if (IS_ERR(server)) {
2434                 error = PTR_ERR(server);
2435                 goto out_err_noserver;
2436         }
2437         sb_mntdata.server = server;
2438
2439         if (server->flags & NFS_MOUNT_UNSHARED)
2440                 compare_super = NULL;
2441
2442         /* -o noac implies -o sync */
2443         if (server->flags & NFS_MOUNT_NOAC)
2444                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2445
2446         /* Get a superblock - note that we may end up sharing one that already exists */
2447         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2448         if (IS_ERR(s)) {
2449                 error = PTR_ERR(s);
2450                 goto out_err_nosb;
2451         }
2452
2453         if (s->s_fs_info != server) {
2454                 nfs_free_server(server);
2455                 server = NULL;
2456         } else {
2457                 error = nfs_bdi_register(server);
2458                 if (error)
2459                         goto error_splat_bdi;
2460         }
2461
2462         if (!s->s_root) {
2463                 /* initial superblock/root creation */
2464                 nfs_clone_super(s, data->sb);
2465                 nfs_fscache_get_super_cookie(s, NULL, data);
2466         }
2467
2468         mntroot = nfs_get_root(s, data->fh, dev_name);
2469         if (IS_ERR(mntroot)) {
2470                 error = PTR_ERR(mntroot);
2471                 goto error_splat_super;
2472         }
2473         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2474                 dput(mntroot);
2475                 error = -ESTALE;
2476                 goto error_splat_super;
2477         }
2478
2479         s->s_flags |= MS_ACTIVE;
2480
2481         /* clone any lsm security options from the parent to the new sb */
2482         security_sb_clone_mnt_opts(data->sb, s);
2483
2484         dprintk("<-- nfs_xdev_mount() = 0\n");
2485         return mntroot;
2486
2487 out_err_nosb:
2488         nfs_free_server(server);
2489 out_err_noserver:
2490         dprintk("<-- nfs_xdev_mount() = %d [error]\n", error);
2491         return ERR_PTR(error);
2492
2493 error_splat_super:
2494         if (server && !s->s_root)
2495                 bdi_unregister(&server->backing_dev_info);
2496 error_splat_bdi:
2497         deactivate_locked_super(s);
2498         dprintk("<-- nfs_xdev_mount() = %d [splat]\n", error);
2499         return ERR_PTR(error);
2500 }
2501
2502 #ifdef CONFIG_NFS_V4
2503
2504 /*
2505  * Finish setting up a cloned NFS4 superblock
2506  */
2507 static void nfs4_clone_super(struct super_block *sb,
2508                             const struct super_block *old_sb)
2509 {
2510         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2511         sb->s_blocksize = old_sb->s_blocksize;
2512         sb->s_maxbytes = old_sb->s_maxbytes;
2513         sb->s_time_gran = 1;
2514         sb->s_op = old_sb->s_op;
2515         /*
2516          * The VFS shouldn't apply the umask to mode bits. We will do
2517          * so ourselves when necessary.
2518          */
2519         sb->s_flags  |= MS_POSIXACL;
2520         sb->s_xattr  = old_sb->s_xattr;
2521         nfs_initialise_sb(sb);
2522 }
2523
2524 /*
2525  * Set up an NFS4 superblock
2526  */
2527 static void nfs4_fill_super(struct super_block *sb)
2528 {
2529         sb->s_time_gran = 1;
2530         sb->s_op = &nfs4_sops;
2531         /*
2532          * The VFS shouldn't apply the umask to mode bits. We will do
2533          * so ourselves when necessary.
2534          */
2535         sb->s_flags  |= MS_POSIXACL;
2536         sb->s_xattr = nfs4_xattr_handlers;
2537         nfs_initialise_sb(sb);
2538 }
2539
2540 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2541 {
2542         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2543                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2544 }
2545
2546 static int nfs4_validate_text_mount_data(void *options,
2547                                          struct nfs_parsed_mount_data *args,
2548                                          const char *dev_name)
2549 {
2550         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2551
2552         nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
2553
2554         nfs_validate_transport_protocol(args);
2555
2556         nfs4_validate_mount_flags(args);
2557
2558         if (args->version != 4) {
2559                 dfprintk(MOUNT,
2560                          "NFS4: Illegal mount version\n");
2561                 return -EINVAL;
2562         }
2563
2564         if (args->auth_flavor_len > 1) {
2565                 dfprintk(MOUNT,
2566                          "NFS4: Too many RPC auth flavours specified\n");
2567                 return -EINVAL;
2568         }
2569
2570         return nfs_parse_devname(dev_name,
2571                                    &args->nfs_server.hostname,
2572                                    NFS4_MAXNAMLEN,
2573                                    &args->nfs_server.export_path,
2574                                    NFS4_MAXPATHLEN);
2575 }
2576
2577 /*
2578  * Validate NFSv4 mount options
2579  */
2580 static int nfs4_validate_mount_data(void *options,
2581                                     struct nfs_parsed_mount_data *args,
2582                                     const char *dev_name)
2583 {
2584         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2585         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2586         char *c;
2587
2588         if (data == NULL)
2589                 goto out_no_data;
2590
2591         switch (data->version) {
2592         case 1:
2593                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2594                         goto out_no_address;
2595                 if (data->host_addrlen == 0)
2596                         goto out_no_address;
2597                 args->nfs_server.addrlen = data->host_addrlen;
2598                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2599                         return -EFAULT;
2600                 if (!nfs_verify_server_address(sap))
2601                         goto out_no_address;
2602
2603                 if (data->auth_flavourlen) {
2604                         if (data->auth_flavourlen > 1)
2605                                 goto out_inval_auth;
2606                         if (copy_from_user(&args->auth_flavors[0],
2607                                            data->auth_flavours,
2608                                            sizeof(args->auth_flavors[0])))
2609                                 return -EFAULT;
2610                 }
2611
2612                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2613                 if (IS_ERR(c))
2614                         return PTR_ERR(c);
2615                 args->nfs_server.hostname = c;
2616
2617                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2618                 if (IS_ERR(c))
2619                         return PTR_ERR(c);
2620                 args->nfs_server.export_path = c;
2621                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2622
2623                 c = strndup_user(data->client_addr.data, 16);
2624                 if (IS_ERR(c))
2625                         return PTR_ERR(c);
2626                 args->client_address = c;
2627
2628                 /*
2629                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2630                  * can deal with.
2631                  */
2632
2633                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2634                 args->rsize     = data->rsize;
2635                 args->wsize     = data->wsize;
2636                 args->timeo     = data->timeo;
2637                 args->retrans   = data->retrans;
2638                 args->acregmin  = data->acregmin;
2639                 args->acregmax  = data->acregmax;
2640                 args->acdirmin  = data->acdirmin;
2641                 args->acdirmax  = data->acdirmax;
2642                 args->nfs_server.protocol = data->proto;
2643                 nfs_validate_transport_protocol(args);
2644
2645                 break;
2646         default:
2647                 if (nfs_parse_mount_options((char *)options, args) == 0)
2648                         return -EINVAL;
2649
2650                 if (!nfs_verify_server_address(sap))
2651                         return -EINVAL;
2652
2653                 return nfs4_validate_text_mount_data(options, args, dev_name);
2654         }
2655
2656         return 0;
2657
2658 out_no_data:
2659         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2660         return -EINVAL;
2661
2662 out_inval_auth:
2663         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2664                  data->auth_flavourlen);
2665         return -EINVAL;
2666
2667 out_no_address:
2668         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2669         return -EINVAL;
2670 }
2671
2672 /*
2673  * Get the superblock for the NFS4 root partition
2674  */
2675 static struct dentry *
2676 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
2677                   const char *dev_name, void *raw_data)
2678 {
2679         struct nfs_parsed_mount_data *data = raw_data;
2680         struct super_block *s;
2681         struct nfs_server *server;
2682         struct nfs_fh *mntfh;
2683         struct dentry *mntroot;
2684         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2685         struct nfs_sb_mountdata sb_mntdata = {
2686                 .mntflags = flags,
2687         };
2688         int error = -ENOMEM;
2689
2690         mntfh = nfs_alloc_fhandle();
2691         if (data == NULL || mntfh == NULL)
2692                 goto out;
2693
2694         /* Get a volume representation */
2695         server = nfs4_create_server(data, mntfh);
2696         if (IS_ERR(server)) {
2697                 error = PTR_ERR(server);
2698                 goto out;
2699         }
2700         sb_mntdata.server = server;
2701
2702         if (server->flags & NFS4_MOUNT_UNSHARED)
2703                 compare_super = NULL;
2704
2705         /* -o noac implies -o sync */
2706         if (server->flags & NFS_MOUNT_NOAC)
2707                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2708
2709         /* Get a superblock - note that we may end up sharing one that already exists */
2710         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2711         if (IS_ERR(s)) {
2712                 error = PTR_ERR(s);
2713                 goto out_free;
2714         }
2715
2716         if (s->s_fs_info != server) {
2717                 nfs_free_server(server);
2718                 server = NULL;
2719         } else {
2720                 error = nfs_bdi_register(server);
2721                 if (error)
2722                         goto error_splat_bdi;
2723         }
2724
2725         if (!s->s_root) {
2726                 /* initial superblock/root creation */
2727                 nfs4_fill_super(s);
2728                 nfs_fscache_get_super_cookie(s, data->fscache_uniq, NULL);
2729         }
2730
2731         mntroot = nfs4_get_root(s, mntfh, dev_name);
2732         if (IS_ERR(mntroot)) {
2733                 error = PTR_ERR(mntroot);
2734                 goto error_splat_super;
2735         }
2736
2737         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2738         if (error)
2739                 goto error_splat_root;
2740
2741         s->s_flags |= MS_ACTIVE;
2742
2743         nfs_free_fhandle(mntfh);
2744         return mntroot;
2745
2746 out:
2747         nfs_free_fhandle(mntfh);
2748         return ERR_PTR(error);
2749
2750 out_free:
2751         nfs_free_server(server);
2752         goto out;
2753
2754 error_splat_root:
2755         dput(mntroot);
2756 error_splat_super:
2757         if (server && !s->s_root)
2758                 bdi_unregister(&server->backing_dev_info);
2759 error_splat_bdi:
2760         deactivate_locked_super(s);
2761         goto out;
2762 }
2763
2764 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
2765                 int flags, void *data, const char *hostname)
2766 {
2767         struct vfsmount *root_mnt;
2768         char *root_devname;
2769         size_t len;
2770
2771         len = strlen(hostname) + 3;
2772         root_devname = kmalloc(len, GFP_KERNEL);
2773         if (root_devname == NULL)
2774                 return ERR_PTR(-ENOMEM);
2775         snprintf(root_devname, len, "%s:/", hostname);
2776         root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
2777         kfree(root_devname);
2778         return root_mnt;
2779 }
2780
2781 struct nfs_referral_count {
2782         struct list_head list;
2783         const struct task_struct *task;
2784         unsigned int referral_count;
2785 };
2786
2787 static LIST_HEAD(nfs_referral_count_list);
2788 static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
2789
2790 static struct nfs_referral_count *nfs_find_referral_count(void)
2791 {
2792         struct nfs_referral_count *p;
2793
2794         list_for_each_entry(p, &nfs_referral_count_list, list) {
2795                 if (p->task == current)
2796                         return p;
2797         }
2798         return NULL;
2799 }
2800
2801 #define NFS_MAX_NESTED_REFERRALS 2
2802
2803 static int nfs_referral_loop_protect(void)
2804 {
2805         struct nfs_referral_count *p, *new;
2806         int ret = -ENOMEM;
2807
2808         new = kmalloc(sizeof(*new), GFP_KERNEL);
2809         if (!new)
2810                 goto out;
2811         new->task = current;
2812         new->referral_count = 1;
2813
2814         ret = 0;
2815         spin_lock(&nfs_referral_count_list_lock);
2816         p = nfs_find_referral_count();
2817         if (p != NULL) {
2818                 if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
2819                         ret = -ELOOP;
2820                 else
2821                         p->referral_count++;
2822         } else {
2823                 list_add(&new->list, &nfs_referral_count_list);
2824                 new = NULL;
2825         }
2826         spin_unlock(&nfs_referral_count_list_lock);
2827         kfree(new);
2828 out:
2829         return ret;
2830 }
2831
2832 static void nfs_referral_loop_unprotect(void)
2833 {
2834         struct nfs_referral_count *p;
2835
2836         spin_lock(&nfs_referral_count_list_lock);
2837         p = nfs_find_referral_count();
2838         p->referral_count--;
2839         if (p->referral_count == 0)
2840                 list_del(&p->list);
2841         else
2842                 p = NULL;
2843         spin_unlock(&nfs_referral_count_list_lock);
2844         kfree(p);
2845 }
2846
2847 static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
2848                 const char *export_path)
2849 {
2850         struct dentry *dentry;
2851         int err;
2852
2853         if (IS_ERR(root_mnt))
2854                 return ERR_CAST(root_mnt);
2855
2856         err = nfs_referral_loop_protect();
2857         if (err) {
2858                 mntput(root_mnt);
2859                 return ERR_PTR(err);
2860         }
2861
2862         dentry = mount_subtree(root_mnt, export_path);
2863         nfs_referral_loop_unprotect();
2864
2865         return dentry;
2866 }
2867
2868 static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
2869                          struct nfs_parsed_mount_data *data)
2870 {
2871         char *export_path;
2872         struct vfsmount *root_mnt;
2873         struct dentry *res;
2874
2875         dfprintk(MOUNT, "--> nfs4_try_mount()\n");
2876
2877         export_path = data->nfs_server.export_path;
2878         data->nfs_server.export_path = "/";
2879         root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, data,
2880                         data->nfs_server.hostname);
2881         data->nfs_server.export_path = export_path;
2882
2883         res = nfs_follow_remote_path(root_mnt, export_path);
2884
2885         dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
2886                         IS_ERR(res) ? PTR_ERR(res) : 0,
2887                         IS_ERR(res) ? " [error]" : "");
2888         return res;
2889 }
2890
2891 /*
2892  * Get the superblock for an NFS4 mountpoint
2893  */
2894 static struct dentry *nfs4_mount(struct file_system_type *fs_type,
2895         int flags, const char *dev_name, void *raw_data)
2896 {
2897         struct nfs_parsed_mount_data *data;
2898         int error = -ENOMEM;
2899         struct dentry *res = ERR_PTR(-ENOMEM);
2900
2901         data = nfs_alloc_parsed_mount_data(4);
2902         if (data == NULL)
2903                 goto out;
2904
2905         /* Validate the mount data */
2906         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2907         if (error < 0) {
2908                 res = ERR_PTR(error);
2909                 goto out;
2910         }
2911
2912         res = nfs4_try_mount(flags, dev_name, data);
2913         if (IS_ERR(res))
2914                 error = PTR_ERR(res);
2915
2916 out:
2917         nfs_free_parsed_mount_data(data);
2918         dprintk("<-- nfs4_mount() = %d%s\n", error,
2919                         error != 0 ? " [error]" : "");
2920         return res;
2921 }
2922
2923 static void nfs4_kill_super(struct super_block *sb)
2924 {
2925         struct nfs_server *server = NFS_SB(sb);
2926
2927         dprintk("--> %s\n", __func__);
2928         nfs_super_return_all_delegations(sb);
2929         kill_anon_super(sb);
2930         nfs_fscache_release_super_cookie(sb);
2931         nfs_free_server(server);
2932         dprintk("<-- %s\n", __func__);
2933 }
2934
2935 /*
2936  * Clone an NFS4 server record on xdev traversal (FSID-change)
2937  */
2938 static struct dentry *
2939 nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
2940                  const char *dev_name, void *raw_data)
2941 {
2942         struct nfs_clone_mount *data = raw_data;
2943         struct super_block *s;
2944         struct nfs_server *server;
2945         struct dentry *mntroot;
2946         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2947         struct nfs_sb_mountdata sb_mntdata = {
2948                 .mntflags = flags,
2949         };
2950         int error;
2951
2952         dprintk("--> nfs4_xdev_mount()\n");
2953
2954         /* create a new volume representation */
2955         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2956         if (IS_ERR(server)) {
2957                 error = PTR_ERR(server);
2958                 goto out_err_noserver;
2959         }
2960         sb_mntdata.server = server;
2961
2962         if (server->flags & NFS4_MOUNT_UNSHARED)
2963                 compare_super = NULL;
2964
2965         /* -o noac implies -o sync */
2966         if (server->flags & NFS_MOUNT_NOAC)
2967                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2968
2969         /* Get a superblock - note that we may end up sharing one that already exists */
2970         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2971         if (IS_ERR(s)) {
2972                 error = PTR_ERR(s);
2973                 goto out_err_nosb;
2974         }
2975
2976         if (s->s_fs_info != server) {
2977                 nfs_free_server(server);
2978                 server = NULL;
2979         } else {
2980                 error = nfs_bdi_register(server);
2981                 if (error)
2982                         goto error_splat_bdi;
2983         }
2984
2985         if (!s->s_root) {
2986                 /* initial superblock/root creation */
2987                 nfs4_clone_super(s, data->sb);
2988                 nfs_fscache_get_super_cookie(s, NULL, data);
2989         }
2990
2991         mntroot = nfs4_get_root(s, data->fh, dev_name);
2992         if (IS_ERR(mntroot)) {
2993                 error = PTR_ERR(mntroot);
2994                 goto error_splat_super;
2995         }
2996         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2997                 dput(mntroot);
2998                 error = -ESTALE;
2999                 goto error_splat_super;
3000         }
3001
3002         s->s_flags |= MS_ACTIVE;
3003
3004         security_sb_clone_mnt_opts(data->sb, s);
3005
3006         dprintk("<-- nfs4_xdev_mount() = 0\n");
3007         return mntroot;
3008
3009 out_err_nosb:
3010         nfs_free_server(server);
3011 out_err_noserver:
3012         dprintk("<-- nfs4_xdev_mount() = %d [error]\n", error);
3013         return ERR_PTR(error);
3014
3015 error_splat_super:
3016         if (server && !s->s_root)
3017                 bdi_unregister(&server->backing_dev_info);
3018 error_splat_bdi:
3019         deactivate_locked_super(s);
3020         dprintk("<-- nfs4_xdev_mount() = %d [splat]\n", error);
3021         return ERR_PTR(error);
3022 }
3023
3024 static struct dentry *
3025 nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
3026                            const char *dev_name, void *raw_data)
3027 {
3028         struct nfs_clone_mount *data = raw_data;
3029         struct super_block *s;
3030         struct nfs_server *server;
3031         struct dentry *mntroot;
3032         struct nfs_fh *mntfh;
3033         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
3034         struct nfs_sb_mountdata sb_mntdata = {
3035                 .mntflags = flags,
3036         };
3037         int error = -ENOMEM;
3038
3039         dprintk("--> nfs4_referral_get_sb()\n");
3040
3041         mntfh = nfs_alloc_fhandle();
3042         if (mntfh == NULL)
3043                 goto out_err_nofh;
3044
3045         /* create a new volume representation */
3046         server = nfs4_create_referral_server(data, mntfh);
3047         if (IS_ERR(server)) {
3048                 error = PTR_ERR(server);
3049                 goto out_err_noserver;
3050         }
3051         sb_mntdata.server = server;
3052
3053         if (server->flags & NFS4_MOUNT_UNSHARED)
3054                 compare_super = NULL;
3055
3056         /* -o noac implies -o sync */
3057         if (server->flags & NFS_MOUNT_NOAC)
3058                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
3059
3060         /* Get a superblock - note that we may end up sharing one that already exists */
3061         s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
3062         if (IS_ERR(s)) {
3063                 error = PTR_ERR(s);
3064                 goto out_err_nosb;
3065         }
3066
3067         if (s->s_fs_info != server) {
3068                 nfs_free_server(server);
3069                 server = NULL;
3070         } else {
3071                 error = nfs_bdi_register(server);
3072                 if (error)
3073                         goto error_splat_bdi;
3074         }
3075
3076         if (!s->s_root) {
3077                 /* initial superblock/root creation */
3078                 nfs4_fill_super(s);
3079                 nfs_fscache_get_super_cookie(s, NULL, data);
3080         }
3081
3082         mntroot = nfs4_get_root(s, mntfh, dev_name);
3083         if (IS_ERR(mntroot)) {
3084                 error = PTR_ERR(mntroot);
3085                 goto error_splat_super;
3086         }
3087         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
3088                 dput(mntroot);
3089                 error = -ESTALE;
3090                 goto error_splat_super;
3091         }
3092
3093         s->s_flags |= MS_ACTIVE;
3094
3095         security_sb_clone_mnt_opts(data->sb, s);
3096
3097         nfs_free_fhandle(mntfh);
3098         dprintk("<-- nfs4_referral_get_sb() = 0\n");
3099         return mntroot;
3100
3101 out_err_nosb:
3102         nfs_free_server(server);
3103 out_err_noserver:
3104         nfs_free_fhandle(mntfh);
3105 out_err_nofh:
3106         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
3107         return ERR_PTR(error);
3108
3109 error_splat_super:
3110         if (server && !s->s_root)
3111                 bdi_unregister(&server->backing_dev_info);
3112 error_splat_bdi:
3113         deactivate_locked_super(s);
3114         nfs_free_fhandle(mntfh);
3115         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
3116         return ERR_PTR(error);
3117 }
3118
3119 /*
3120  * Create an NFS4 server record on referral traversal
3121  */
3122 static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
3123                 int flags, const char *dev_name, void *raw_data)
3124 {
3125         struct nfs_clone_mount *data = raw_data;
3126         char *export_path;
3127         struct vfsmount *root_mnt;
3128         struct dentry *res;
3129
3130         dprintk("--> nfs4_referral_mount()\n");
3131
3132         export_path = data->mnt_path;
3133         data->mnt_path = "/";
3134
3135         root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
3136                         flags, data, data->hostname);
3137         data->mnt_path = export_path;
3138
3139         res = nfs_follow_remote_path(root_mnt, export_path);
3140         dprintk("<-- nfs4_referral_mount() = %ld%s\n",
3141                         IS_ERR(res) ? PTR_ERR(res) : 0,
3142                         IS_ERR(res) ? " [error]" : "");
3143         return res;
3144 }
3145
3146 #endif /* CONFIG_NFS_V4 */