fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/addr.h>
  35 #include <linux/sunrpc/stats.h>
  36 #include <linux/sunrpc/metrics.h>
  37 #include <linux/sunrpc/xprtsock.h>
  38 #include <linux/sunrpc/xprtrdma.h>
  39 #include <linux/nfs_fs.h>
  40 #include <linux/nfs_mount.h>
  41 #include <linux/nfs4_mount.h>
  42 #include <linux/lockd/bind.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/namei.h>
  46 #include <linux/nfs_idmap.h>
  47 #include <linux/vfs.h>
  48 #include <linux/inet.h>
  49 #include <linux/in6.h>
  50 #include <linux/slab.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56 #include <linux/nsproxy.h>
  57 #include <linux/rcupdate.h>
  58
  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 "nfs4session.h"
  68 #include "pnfs.h"
  69 #include "nfs.h"
  70
  71 #define NFSDBG_FACILITY         NFSDBG_VFS
  72 #define NFS_TEXT_DATA           1
  73
  74 #if IS_ENABLED(CONFIG_NFS_V3)
  75 #define NFS_DEFAULT_VERSION 3
  76 #else
  77 #define NFS_DEFAULT_VERSION 2
  78 #endif
  79
  80 enum {
  81         /* Mount options that take no arguments */
  82         Opt_soft, Opt_hard,
  83         Opt_posix, Opt_noposix,
  84         Opt_cto, Opt_nocto,
  85         Opt_ac, Opt_noac,
  86         Opt_lock, Opt_nolock,
  87         Opt_udp, Opt_tcp, Opt_rdma,
  88         Opt_acl, Opt_noacl,
  89         Opt_rdirplus, Opt_nordirplus,
  90         Opt_sharecache, Opt_nosharecache,
  91         Opt_resvport, Opt_noresvport,
  92         Opt_fscache, Opt_nofscache,
  93         Opt_migration, Opt_nomigration,
  94
  95         /* Mount options that take integer arguments */
  96         Opt_port,
  97         Opt_rsize, Opt_wsize, Opt_bsize,
  98         Opt_timeo, Opt_retrans,
  99         Opt_acregmin, Opt_acregmax,
 100         Opt_acdirmin, Opt_acdirmax,
 101         Opt_actimeo,
 102         Opt_namelen,
 103         Opt_mountport,
 104         Opt_mountvers,
 105         Opt_minorversion,
 106
 107         /* Mount options that take string arguments */
 108         Opt_nfsvers,
 109         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 110         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 111         Opt_lookupcache,
 112         Opt_fscache_uniq,
 113         Opt_local_lock,
 114
 115         /* Special mount options */
 116         Opt_userspace, Opt_deprecated, Opt_sloppy,
 117
 118         Opt_err
 119 };
 120
 121 static const match_table_t nfs_mount_option_tokens = {
 122         { Opt_userspace, "bg" },
 123         { Opt_userspace, "fg" },
 124         { Opt_userspace, "retry=%s" },
 125
 126         { Opt_sloppy, "sloppy" },
 127
 128         { Opt_soft, "soft" },
 129         { Opt_hard, "hard" },
 130         { Opt_deprecated, "intr" },
 131         { Opt_deprecated, "nointr" },
 132         { Opt_posix, "posix" },
 133         { Opt_noposix, "noposix" },
 134         { Opt_cto, "cto" },
 135         { Opt_nocto, "nocto" },
 136         { Opt_ac, "ac" },
 137         { Opt_noac, "noac" },
 138         { Opt_lock, "lock" },
 139         { Opt_nolock, "nolock" },
 140         { Opt_udp, "udp" },
 141         { Opt_tcp, "tcp" },
 142         { Opt_rdma, "rdma" },
 143         { Opt_acl, "acl" },
 144         { Opt_noacl, "noacl" },
 145         { Opt_rdirplus, "rdirplus" },
 146         { Opt_nordirplus, "nordirplus" },
 147         { Opt_sharecache, "sharecache" },
 148         { Opt_nosharecache, "nosharecache" },
 149         { Opt_resvport, "resvport" },
 150         { Opt_noresvport, "noresvport" },
 151         { Opt_fscache, "fsc" },
 152         { Opt_nofscache, "nofsc" },
 153         { Opt_migration, "migration" },
 154         { Opt_nomigration, "nomigration" },
 155
 156         { Opt_port, "port=%s" },
 157         { Opt_rsize, "rsize=%s" },
 158         { Opt_wsize, "wsize=%s" },
 159         { Opt_bsize, "bsize=%s" },
 160         { Opt_timeo, "timeo=%s" },
 161         { Opt_retrans, "retrans=%s" },
 162         { Opt_acregmin, "acregmin=%s" },
 163         { Opt_acregmax, "acregmax=%s" },
 164         { Opt_acdirmin, "acdirmin=%s" },
 165         { Opt_acdirmax, "acdirmax=%s" },
 166         { Opt_actimeo, "actimeo=%s" },
 167         { Opt_namelen, "namlen=%s" },
 168         { Opt_mountport, "mountport=%s" },
 169         { Opt_mountvers, "mountvers=%s" },
 170         { Opt_minorversion, "minorversion=%s" },
 171
 172         { Opt_nfsvers, "nfsvers=%s" },
 173         { Opt_nfsvers, "vers=%s" },
 174
 175         { Opt_sec, "sec=%s" },
 176         { Opt_proto, "proto=%s" },
 177         { Opt_mountproto, "mountproto=%s" },
 178         { Opt_addr, "addr=%s" },
 179         { Opt_clientaddr, "clientaddr=%s" },
 180         { Opt_mounthost, "mounthost=%s" },
 181         { Opt_mountaddr, "mountaddr=%s" },
 182
 183         { Opt_lookupcache, "lookupcache=%s" },
 184         { Opt_fscache_uniq, "fsc=%s" },
 185         { Opt_local_lock, "local_lock=%s" },
 186
 187         /* The following needs to be listed after all other options */
 188         { Opt_nfsvers, "v%s" },
 189
 190         { Opt_err, NULL }
 191 };
 192
 193 enum {
 194         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 195
 196         Opt_xprt_err
 197 };
 198
 199 static const match_table_t nfs_xprt_protocol_tokens = {
 200         { Opt_xprt_udp, "udp" },
 201         { Opt_xprt_udp6, "udp6" },
 202         { Opt_xprt_tcp, "tcp" },
 203         { Opt_xprt_tcp6, "tcp6" },
 204         { Opt_xprt_rdma, "rdma" },
 205
 206         { Opt_xprt_err, NULL }
 207 };
 208
 209 enum {
 210         Opt_sec_none, Opt_sec_sys,
 211         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 212         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 213         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 214
 215         Opt_sec_err
 216 };
 217
 218 static const match_table_t nfs_secflavor_tokens = {
 219         { Opt_sec_none, "none" },
 220         { Opt_sec_none, "null" },
 221         { Opt_sec_sys, "sys" },
 222
 223         { Opt_sec_krb5, "krb5" },
 224         { Opt_sec_krb5i, "krb5i" },
 225         { Opt_sec_krb5p, "krb5p" },
 226
 227         { Opt_sec_lkey, "lkey" },
 228         { Opt_sec_lkeyi, "lkeyi" },
 229         { Opt_sec_lkeyp, "lkeyp" },
 230
 231         { Opt_sec_spkm, "spkm3" },
 232         { Opt_sec_spkmi, "spkm3i" },
 233         { Opt_sec_spkmp, "spkm3p" },
 234
 235         { Opt_sec_err, NULL }
 236 };
 237
 238 enum {
 239         Opt_lookupcache_all, Opt_lookupcache_positive,
 240         Opt_lookupcache_none,
 241
 242         Opt_lookupcache_err
 243 };
 244
 245 static match_table_t nfs_lookupcache_tokens = {
 246         { Opt_lookupcache_all, "all" },
 247         { Opt_lookupcache_positive, "pos" },
 248         { Opt_lookupcache_positive, "positive" },
 249         { Opt_lookupcache_none, "none" },
 250
 251         { Opt_lookupcache_err, NULL }
 252 };
 253
 254 enum {
 255         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 256         Opt_local_lock_none,
 257
 258         Opt_local_lock_err
 259 };
 260
 261 static match_table_t nfs_local_lock_tokens = {
 262         { Opt_local_lock_all, "all" },
 263         { Opt_local_lock_flock, "flock" },
 264         { Opt_local_lock_posix, "posix" },
 265         { Opt_local_lock_none, "none" },
 266
 267         { Opt_local_lock_err, NULL }
 268 };
 269
 270 enum {
 271         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 272         Opt_vers_4_1,
 273
 274         Opt_vers_err
 275 };
 276
 277 static match_table_t nfs_vers_tokens = {
 278         { Opt_vers_2, "2" },
 279         { Opt_vers_3, "3" },
 280         { Opt_vers_4, "4" },
 281         { Opt_vers_4_0, "4.0" },
 282         { Opt_vers_4_1, "4.1" },
 283
 284         { Opt_vers_err, NULL }
 285 };
 286
 287 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 288                 int flags, const char *dev_name, void *raw_data);
 289
 290 struct file_system_type nfs_fs_type = {
 291         .owner          = THIS_MODULE,
 292         .name           = "nfs",
 293         .mount          = nfs_fs_mount,
 294         .kill_sb        = nfs_kill_super,
 295         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 296 };
 297 MODULE_ALIAS_FS("nfs");
 298 EXPORT_SYMBOL_GPL(nfs_fs_type);
 299
 300 struct file_system_type nfs_xdev_fs_type = {
 301         .owner          = THIS_MODULE,
 302         .name           = "nfs",
 303         .mount          = nfs_xdev_mount,
 304         .kill_sb        = nfs_kill_super,
 305         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 306 };
 307
 308 const struct super_operations nfs_sops = {
 309         .alloc_inode    = nfs_alloc_inode,
 310         .destroy_inode  = nfs_destroy_inode,
 311         .write_inode    = nfs_write_inode,
 312         .drop_inode     = nfs_drop_inode,
 313         .put_super      = nfs_put_super,
 314         .statfs         = nfs_statfs,
 315         .evict_inode    = nfs_evict_inode,
 316         .umount_begin   = nfs_umount_begin,
 317         .show_options   = nfs_show_options,
 318         .show_devname   = nfs_show_devname,
 319         .show_path      = nfs_show_path,
 320         .show_stats     = nfs_show_stats,
 321         .remount_fs     = nfs_remount,
 322 };
 323 EXPORT_SYMBOL_GPL(nfs_sops);
 324
 325 #if IS_ENABLED(CONFIG_NFS_V4)
 326 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 327 static int nfs4_validate_mount_data(void *options,
 328         struct nfs_parsed_mount_data *args, const char *dev_name);
 329
 330 struct file_system_type nfs4_fs_type = {
 331         .owner          = THIS_MODULE,
 332         .name           = "nfs4",
 333         .mount          = nfs_fs_mount,
 334         .kill_sb        = nfs_kill_super,
 335         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 336 };
 337 MODULE_ALIAS_FS("nfs4");
 338 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 339
 340 static int __init register_nfs4_fs(void)
 341 {
 342         return register_filesystem(&nfs4_fs_type);
 343 }
 344
 345 static void unregister_nfs4_fs(void)
 346 {
 347         unregister_filesystem(&nfs4_fs_type);
 348 }
 349 #else
 350 static int __init register_nfs4_fs(void)
 351 {
 352         return 0;
 353 }
 354
 355 static void unregister_nfs4_fs(void)
 356 {
 357 }
 358 #endif
 359
 360 static struct shrinker acl_shrinker = {
 361         .shrink         = nfs_access_cache_shrinker,
 362         .seeks          = DEFAULT_SEEKS,
 363 };
 364
 365 /*
 366  * Register the NFS filesystems
 367  */
 368 int __init register_nfs_fs(void)
 369 {
 370         int ret;
 371
 372         ret = register_filesystem(&nfs_fs_type);
 373         if (ret < 0)
 374                 goto error_0;
 375
 376         ret = register_nfs4_fs();
 377         if (ret < 0)
 378                 goto error_1;
 379
 380         ret = nfs_register_sysctl();
 381         if (ret < 0)
 382                 goto error_2;
 383         register_shrinker(&acl_shrinker);
 384         return 0;
 385
 386 error_2:
 387         unregister_nfs4_fs();
 388 error_1:
 389         unregister_filesystem(&nfs_fs_type);
 390 error_0:
 391         return ret;
 392 }
 393
 394 /*
 395  * Unregister the NFS filesystems
 396  */
 397 void __exit unregister_nfs_fs(void)
 398 {
 399         unregister_shrinker(&acl_shrinker);
 400         nfs_unregister_sysctl();
 401         unregister_nfs4_fs();
 402         unregister_filesystem(&nfs_fs_type);
 403 }
 404
 405 void nfs_sb_active(struct super_block *sb)
 406 {
 407         struct nfs_server *server = NFS_SB(sb);
 408
 409         if (atomic_inc_return(&server->active) == 1)
 410                 atomic_inc(&sb->s_active);
 411 }
 412 EXPORT_SYMBOL_GPL(nfs_sb_active);
 413
 414 void nfs_sb_deactive(struct super_block *sb)
 415 {
 416         struct nfs_server *server = NFS_SB(sb);
 417
 418         if (atomic_dec_and_test(&server->active))
 419                 deactivate_super(sb);
 420 }
 421 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 422
 423 /*
 424  * Deliver file system statistics to userspace
 425  */
 426 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 427 {
 428         struct nfs_server *server = NFS_SB(dentry->d_sb);
 429         unsigned char blockbits;
 430         unsigned long blockres;
 431         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 432         struct nfs_fsstat res;
 433         int error = -ENOMEM;
 434
 435         res.fattr = nfs_alloc_fattr();
 436         if (res.fattr == NULL)
 437                 goto out_err;
 438
 439         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 440         if (unlikely(error == -ESTALE)) {
 441                 struct dentry *pd_dentry;
 442
 443                 pd_dentry = dget_parent(dentry);
 444                 if (pd_dentry != NULL) {
 445                         nfs_zap_caches(pd_dentry->d_inode);
 446                         dput(pd_dentry);
 447                 }
 448         }
 449         nfs_free_fattr(res.fattr);
 450         if (error < 0)
 451                 goto out_err;
 452
 453         buf->f_type = NFS_SUPER_MAGIC;
 454
 455         /*
 456          * Current versions of glibc do not correctly handle the
 457          * case where f_frsize != f_bsize.  Eventually we want to
 458          * report the value of wtmult in this field.
 459          */
 460         buf->f_frsize = dentry->d_sb->s_blocksize;
 461
 462         /*
 463          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 464          * are reported in units of f_frsize.  Linux hasn't had
 465          * an f_frsize field in its statfs struct until recently,
 466          * thus historically Linux's sys_statfs reports these
 467          * fields in units of f_bsize.
 468          */
 469         buf->f_bsize = dentry->d_sb->s_blocksize;
 470         blockbits = dentry->d_sb->s_blocksize_bits;
 471         blockres = (1 << blockbits) - 1;
 472         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 473         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 474         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 475
 476         buf->f_files = res.tfiles;
 477         buf->f_ffree = res.afiles;
 478
 479         buf->f_namelen = server->namelen;
 480
 481         return 0;
 482
 483  out_err:
 484         dprintk("%s: statfs error = %d\n", __func__, -error);
 485         return error;
 486 }
 487 EXPORT_SYMBOL_GPL(nfs_statfs);
 488
 489 /*
 490  * Map the security flavour number to a name
 491  */
 492 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 493 {
 494         static const struct {
 495                 rpc_authflavor_t flavour;
 496                 const char *str;
 497         } sec_flavours[] = {
 498                 { RPC_AUTH_NULL, "null" },
 499                 { RPC_AUTH_UNIX, "sys" },
 500                 { RPC_AUTH_GSS_KRB5, "krb5" },
 501                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 502                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 503                 { RPC_AUTH_GSS_LKEY, "lkey" },
 504                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 505                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 506                 { RPC_AUTH_GSS_SPKM, "spkm" },
 507                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 508                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 509                 { UINT_MAX, "unknown" }
 510         };
 511         int i;
 512
 513         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 514                 if (sec_flavours[i].flavour == flavour)
 515                         break;
 516         }
 517         return sec_flavours[i].str;
 518 }
 519
 520 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 521                                   int showdefaults)
 522 {
 523         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 524
 525         seq_printf(m, ",mountproto=");
 526         switch (sap->sa_family) {
 527         case AF_INET:
 528                 switch (nfss->mountd_protocol) {
 529                 case IPPROTO_UDP:
 530                         seq_printf(m, RPCBIND_NETID_UDP);
 531                         break;
 532                 case IPPROTO_TCP:
 533                         seq_printf(m, RPCBIND_NETID_TCP);
 534                         break;
 535                 default:
 536                         if (showdefaults)
 537                                 seq_printf(m, "auto");
 538                 }
 539                 break;
 540         case AF_INET6:
 541                 switch (nfss->mountd_protocol) {
 542                 case IPPROTO_UDP:
 543                         seq_printf(m, RPCBIND_NETID_UDP6);
 544                         break;
 545                 case IPPROTO_TCP:
 546                         seq_printf(m, RPCBIND_NETID_TCP6);
 547                         break;
 548                 default:
 549                         if (showdefaults)
 550                                 seq_printf(m, "auto");
 551                 }
 552                 break;
 553         default:
 554                 if (showdefaults)
 555                         seq_printf(m, "auto");
 556         }
 557 }
 558
 559 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 560                                     int showdefaults)
 561 {
 562         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 563
 564         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 565                 return;
 566
 567         switch (sap->sa_family) {
 568         case AF_INET: {
 569                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 570                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 571                 break;
 572         }
 573         case AF_INET6: {
 574                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 575                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 576                 break;
 577         }
 578         default:
 579                 if (showdefaults)
 580                         seq_printf(m, ",mountaddr=unspecified");
 581         }
 582
 583         if (nfss->mountd_version || showdefaults)
 584                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 585         if ((nfss->mountd_port &&
 586                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 587                 showdefaults)
 588                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 589
 590         nfs_show_mountd_netid(m, nfss, showdefaults);
 591 }
 592
 593 #if IS_ENABLED(CONFIG_NFS_V4)
 594 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 595                                     int showdefaults)
 596 {
 597         struct nfs_client *clp = nfss->nfs_client;
 598
 599         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 600 }
 601 #else
 602 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 603                                     int showdefaults)
 604 {
 605 }
 606 #endif
 607
 608 static void nfs_show_nfs_version(struct seq_file *m,
 609                 unsigned int version,
 610                 unsigned int minorversion)
 611 {
 612         seq_printf(m, ",vers=%u", version);
 613         if (version == 4)
 614                 seq_printf(m, ".%u", minorversion);
 615 }
 616
 617 /*
 618  * Describe the mount options in force on this server representation
 619  */
 620 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 621                                    int showdefaults)
 622 {
 623         static const struct proc_nfs_info {
 624                 int flag;
 625                 const char *str;
 626                 const char *nostr;
 627         } nfs_info[] = {
 628                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 629                 { NFS_MOUNT_POSIX, ",posix", "" },
 630                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 631                 { NFS_MOUNT_NOAC, ",noac", "" },
 632                 { NFS_MOUNT_NONLM, ",nolock", "" },
 633                 { NFS_MOUNT_NOACL, ",noacl", "" },
 634                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 635                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 636                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 637                 { 0, NULL, NULL }
 638         };
 639         const struct proc_nfs_info *nfs_infop;
 640         struct nfs_client *clp = nfss->nfs_client;
 641         u32 version = clp->rpc_ops->version;
 642         int local_flock, local_fcntl;
 643
 644         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 645         seq_printf(m, ",rsize=%u", nfss->rsize);
 646         seq_printf(m, ",wsize=%u", nfss->wsize);
 647         if (nfss->bsize != 0)
 648                 seq_printf(m, ",bsize=%u", nfss->bsize);
 649         seq_printf(m, ",namlen=%u", nfss->namelen);
 650         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 651                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 652         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 653                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 654         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 655                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 656         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 657                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 658         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 659                 if (nfss->flags & nfs_infop->flag)
 660                         seq_puts(m, nfs_infop->str);
 661                 else
 662                         seq_puts(m, nfs_infop->nostr);
 663         }
 664         rcu_read_lock();
 665         seq_printf(m, ",proto=%s",
 666                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 667         rcu_read_unlock();
 668         if (version == 4) {
 669                 if (nfss->port != NFS_PORT)
 670                         seq_printf(m, ",port=%u", nfss->port);
 671         } else
 672                 if (nfss->port)
 673                         seq_printf(m, ",port=%u", nfss->port);
 674
 675         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 676         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 677         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 678
 679         if (version != 4)
 680                 nfs_show_mountd_options(m, nfss, showdefaults);
 681         else
 682                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 683
 684         if (nfss->options & NFS_OPTION_FSCACHE)
 685                 seq_printf(m, ",fsc");
 686
 687         if (nfss->options & NFS_OPTION_MIGRATION)
 688                 seq_printf(m, ",migration");
 689
 690         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 691                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 692                         seq_printf(m, ",lookupcache=none");
 693                 else
 694                         seq_printf(m, ",lookupcache=pos");
 695         }
 696
 697         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 698         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 699
 700         if (!local_flock && !local_fcntl)
 701                 seq_printf(m, ",local_lock=none");
 702         else if (local_flock && local_fcntl)
 703                 seq_printf(m, ",local_lock=all");
 704         else if (local_flock)
 705                 seq_printf(m, ",local_lock=flock");
 706         else
 707                 seq_printf(m, ",local_lock=posix");
 708 }
 709
 710 /*
 711  * Describe the mount options on this VFS mountpoint
 712  */
 713 int nfs_show_options(struct seq_file *m, struct dentry *root)
 714 {
 715         struct nfs_server *nfss = NFS_SB(root->d_sb);
 716
 717         nfs_show_mount_options(m, nfss, 0);
 718
 719         rcu_read_lock();
 720         seq_printf(m, ",addr=%s",
 721                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 722                                                         RPC_DISPLAY_ADDR));
 723         rcu_read_unlock();
 724
 725         return 0;
 726 }
 727 EXPORT_SYMBOL_GPL(nfs_show_options);
 728
 729 #if IS_ENABLED(CONFIG_NFS_V4)
 730 #ifdef CONFIG_NFS_V4_1
 731 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 732 {
 733         if (nfs4_has_session(server->nfs_client))
 734                 seq_printf(m, ",sessions");
 735 }
 736 #else
 737 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 738 #endif
 739 #endif
 740
 741 #ifdef CONFIG_NFS_V4_1
 742 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 743 {
 744         seq_printf(m, ",pnfs=");
 745         if (server->pnfs_curr_ld)
 746                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 747         else
 748                 seq_printf(m, "not configured");
 749 }
 750
 751 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 752 {
 753         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 754                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 755                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 756                            "date='%llu,%u'",
 757                            impl_id->name, impl_id->domain,
 758                            impl_id->date.seconds, impl_id->date.nseconds);
 759         }
 760 }
 761 #else
 762 #if IS_ENABLED(CONFIG_NFS_V4)
 763 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 764 {
 765 }
 766 #endif
 767 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 768 {
 769 }
 770 #endif
 771
 772 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 773 {
 774         char *page = (char *) __get_free_page(GFP_KERNEL);
 775         char *devname, *dummy;
 776         int err = 0;
 777         if (!page)
 778                 return -ENOMEM;
 779         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 780         if (IS_ERR(devname))
 781                 err = PTR_ERR(devname);
 782         else
 783                 seq_escape(m, devname, " \t\n\\");
 784         free_page((unsigned long)page);
 785         return err;
 786 }
 787 EXPORT_SYMBOL_GPL(nfs_show_devname);
 788
 789 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 790 {
 791         seq_puts(m, "/");
 792         return 0;
 793 }
 794 EXPORT_SYMBOL_GPL(nfs_show_path);
 795
 796 /*
 797  * Present statistical information for this VFS mountpoint
 798  */
 799 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 800 {
 801         int i, cpu;
 802         struct nfs_server *nfss = NFS_SB(root->d_sb);
 803         struct rpc_auth *auth = nfss->client->cl_auth;
 804         struct nfs_iostats totals = { };
 805
 806         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 807
 808         /*
 809          * Display all mount option settings
 810          */
 811         seq_printf(m, "\n\topts:\t");
 812         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 813         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 814         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 815         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 816         nfs_show_mount_options(m, nfss, 1);
 817
 818         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 819
 820         show_implementation_id(m, nfss);
 821
 822         seq_printf(m, "\n\tcaps:\t");
 823         seq_printf(m, "caps=0x%x", nfss->caps);
 824         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 825         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 826         seq_printf(m, ",bsize=%u", nfss->bsize);
 827         seq_printf(m, ",namlen=%u", nfss->namelen);
 828
 829 #if IS_ENABLED(CONFIG_NFS_V4)
 830         if (nfss->nfs_client->rpc_ops->version == 4) {
 831                 seq_printf(m, "\n\tnfsv4:\t");
 832                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 833                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 834                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 835                 show_sessions(m, nfss);
 836                 show_pnfs(m, nfss);
 837         }
 838 #endif
 839
 840         /*
 841          * Display security flavor in effect for this mount
 842          */
 843         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 844         if (auth->au_flavor)
 845                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 846
 847         /*
 848          * Display superblock I/O counters
 849          */
 850         for_each_possible_cpu(cpu) {
 851                 struct nfs_iostats *stats;
 852
 853                 preempt_disable();
 854                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 855
 856                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 857                         totals.events[i] += stats->events[i];
 858                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 859                         totals.bytes[i] += stats->bytes[i];
 860 #ifdef CONFIG_NFS_FSCACHE
 861                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 862                         totals.fscache[i] += stats->fscache[i];
 863 #endif
 864
 865                 preempt_enable();
 866         }
 867
 868         seq_printf(m, "\n\tevents:\t");
 869         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 870                 seq_printf(m, "%lu ", totals.events[i]);
 871         seq_printf(m, "\n\tbytes:\t");
 872         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 873                 seq_printf(m, "%Lu ", totals.bytes[i]);
 874 #ifdef CONFIG_NFS_FSCACHE
 875         if (nfss->options & NFS_OPTION_FSCACHE) {
 876                 seq_printf(m, "\n\tfsc:\t");
 877                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 878                         seq_printf(m, "%Lu ", totals.bytes[i]);
 879         }
 880 #endif
 881         seq_printf(m, "\n");
 882
 883         rpc_print_iostats(m, nfss->client);
 884
 885         return 0;
 886 }
 887 EXPORT_SYMBOL_GPL(nfs_show_stats);
 888
 889 /*
 890  * Begin unmount by attempting to remove all automounted mountpoints we added
 891  * in response to xdev traversals and referrals
 892  */
 893 void nfs_umount_begin(struct super_block *sb)
 894 {
 895         struct nfs_server *server;
 896         struct rpc_clnt *rpc;
 897
 898         server = NFS_SB(sb);
 899         /* -EIO all pending I/O */
 900         rpc = server->client_acl;
 901         if (!IS_ERR(rpc))
 902                 rpc_killall_tasks(rpc);
 903         rpc = server->client;
 904         if (!IS_ERR(rpc))
 905                 rpc_killall_tasks(rpc);
 906 }
 907 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 908
 909 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 910 {
 911         struct nfs_parsed_mount_data *data;
 912
 913         data = kzalloc(sizeof(*data), GFP_KERNEL);
 914         if (data) {
 915                 data->acregmin          = NFS_DEF_ACREGMIN;
 916                 data->acregmax          = NFS_DEF_ACREGMAX;
 917                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 918                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 919                 data->mount_server.port = NFS_UNSPEC_PORT;
 920                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 921                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 922                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 923                 data->auth_flavor_len   = 1;
 924                 data->minorversion      = 0;
 925                 data->need_mount        = true;
 926                 data->net               = current->nsproxy->net_ns;
 927                 security_init_mnt_opts(&data->lsm_opts);
 928         }
 929         return data;
 930 }
 931
 932 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 933 {
 934         if (data) {
 935                 kfree(data->client_address);
 936                 kfree(data->mount_server.hostname);
 937                 kfree(data->nfs_server.export_path);
 938                 kfree(data->nfs_server.hostname);
 939                 kfree(data->fscache_uniq);
 940                 security_free_mnt_opts(&data->lsm_opts);
 941                 kfree(data);
 942         }
 943 }
 944
 945 /*
 946  * Sanity-check a server address provided by the mount command.
 947  *
 948  * Address family must be initialized, and address must not be
 949  * the ANY address for that family.
 950  */
 951 static int nfs_verify_server_address(struct sockaddr *addr)
 952 {
 953         switch (addr->sa_family) {
 954         case AF_INET: {
 955                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 956                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 957         }
 958         case AF_INET6: {
 959                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 960                 return !ipv6_addr_any(sa);
 961         }
 962         }
 963
 964         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 965         return 0;
 966 }
 967
 968 /*
 969  * Select between a default port value and a user-specified port value.
 970  * If a zero value is set, then autobind will be used.
 971  */
 972 static void nfs_set_port(struct sockaddr *sap, int *port,
 973                                  const unsigned short default_port)
 974 {
 975         if (*port == NFS_UNSPEC_PORT)
 976                 *port = default_port;
 977
 978         rpc_set_port(sap, *port);
 979 }
 980
 981 /*
 982  * Sanity check the NFS transport protocol.
 983  *
 984  */
 985 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 986 {
 987         switch (mnt->nfs_server.protocol) {
 988         case XPRT_TRANSPORT_UDP:
 989         case XPRT_TRANSPORT_TCP:
 990         case XPRT_TRANSPORT_RDMA:
 991                 break;
 992         default:
 993                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 994         }
 995 }
 996
 997 /*
 998  * For text based NFSv2/v3 mounts, the mount protocol transport default
 999  * settings should depend upon the specified NFS transport.
1000  */
1001 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1002 {
1003         nfs_validate_transport_protocol(mnt);
1004
1005         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1006             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1007                         return;
1008         switch (mnt->nfs_server.protocol) {
1009         case XPRT_TRANSPORT_UDP:
1010                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1011                 break;
1012         case XPRT_TRANSPORT_TCP:
1013         case XPRT_TRANSPORT_RDMA:
1014                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1015         }
1016 }
1017
1018 /*
1019  * Parse the value of the 'sec=' option.
1020  */
1021 static int nfs_parse_security_flavors(char *value,
1022                                       struct nfs_parsed_mount_data *mnt)
1023 {
1024         substring_t args[MAX_OPT_ARGS];
1025
1026         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1027
1028         switch (match_token(value, nfs_secflavor_tokens, args)) {
1029         case Opt_sec_none:
1030                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1031                 break;
1032         case Opt_sec_sys:
1033                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1034                 break;
1035         case Opt_sec_krb5:
1036                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1037                 break;
1038         case Opt_sec_krb5i:
1039                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1040                 break;
1041         case Opt_sec_krb5p:
1042                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1043                 break;
1044         case Opt_sec_lkey:
1045                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1046                 break;
1047         case Opt_sec_lkeyi:
1048                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1049                 break;
1050         case Opt_sec_lkeyp:
1051                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1052                 break;
1053         case Opt_sec_spkm:
1054                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1055                 break;
1056         case Opt_sec_spkmi:
1057                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1058                 break;
1059         case Opt_sec_spkmp:
1060                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1061                 break;
1062         default:
1063                 return 0;
1064         }
1065
1066         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1067         mnt->auth_flavor_len = 1;
1068         return 1;
1069 }
1070
1071 static int nfs_parse_version_string(char *string,
1072                 struct nfs_parsed_mount_data *mnt,
1073                 substring_t *args)
1074 {
1075         mnt->flags &= ~NFS_MOUNT_VER3;
1076         switch (match_token(string, nfs_vers_tokens, args)) {
1077         case Opt_vers_2:
1078                 mnt->version = 2;
1079                 break;
1080         case Opt_vers_3:
1081                 mnt->flags |= NFS_MOUNT_VER3;
1082                 mnt->version = 3;
1083                 break;
1084         case Opt_vers_4:
1085                 /* Backward compatibility option. In future,
1086                  * the mount program should always supply
1087                  * a NFSv4 minor version number.
1088                  */
1089                 mnt->version = 4;
1090                 break;
1091         case Opt_vers_4_0:
1092                 mnt->version = 4;
1093                 mnt->minorversion = 0;
1094                 break;
1095         case Opt_vers_4_1:
1096                 mnt->version = 4;
1097                 mnt->minorversion = 1;
1098                 break;
1099         default:
1100                 return 0;
1101         }
1102         return 1;
1103 }
1104
1105 static int nfs_get_option_str(substring_t args[], char **option)
1106 {
1107         kfree(*option);
1108         *option = match_strdup(args);
1109         return !*option;
1110 }
1111
1112 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1113 {
1114         int rc;
1115         char *string;
1116
1117         string = match_strdup(args);
1118         if (string == NULL)
1119                 return -ENOMEM;
1120         rc = kstrtoul(string, 10, option);
1121         kfree(string);
1122
1123         return rc;
1124 }
1125
1126 /*
1127  * Error-check and convert a string of mount options from user space into
1128  * a data structure.  The whole mount string is processed; bad options are
1129  * skipped as they are encountered.  If there were no errors, return 1;
1130  * otherwise return 0 (zero).
1131  */
1132 static int nfs_parse_mount_options(char *raw,
1133                                    struct nfs_parsed_mount_data *mnt)
1134 {
1135         char *p, *string, *secdata;
1136         int rc, sloppy = 0, invalid_option = 0;
1137         unsigned short protofamily = AF_UNSPEC;
1138         unsigned short mountfamily = AF_UNSPEC;
1139
1140         if (!raw) {
1141                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1142                 return 1;
1143         }
1144         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1145
1146         secdata = alloc_secdata();
1147         if (!secdata)
1148                 goto out_nomem;
1149
1150         rc = security_sb_copy_data(raw, secdata);
1151         if (rc)
1152                 goto out_security_failure;
1153
1154         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1155         if (rc)
1156                 goto out_security_failure;
1157
1158         free_secdata(secdata);
1159
1160         while ((p = strsep(&raw, ",")) != NULL) {
1161                 substring_t args[MAX_OPT_ARGS];
1162                 unsigned long option;
1163                 int token;
1164
1165                 if (!*p)
1166                         continue;
1167
1168                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1169
1170                 token = match_token(p, nfs_mount_option_tokens, args);
1171                 switch (token) {
1172
1173                 /*
1174                  * boolean options:  foo/nofoo
1175                  */
1176                 case Opt_soft:
1177                         mnt->flags |= NFS_MOUNT_SOFT;
1178                         break;
1179                 case Opt_hard:
1180                         mnt->flags &= ~NFS_MOUNT_SOFT;
1181                         break;
1182                 case Opt_posix:
1183                         mnt->flags |= NFS_MOUNT_POSIX;
1184                         break;
1185                 case Opt_noposix:
1186                         mnt->flags &= ~NFS_MOUNT_POSIX;
1187                         break;
1188                 case Opt_cto:
1189                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1190                         break;
1191                 case Opt_nocto:
1192                         mnt->flags |= NFS_MOUNT_NOCTO;
1193                         break;
1194                 case Opt_ac:
1195                         mnt->flags &= ~NFS_MOUNT_NOAC;
1196                         break;
1197                 case Opt_noac:
1198                         mnt->flags |= NFS_MOUNT_NOAC;
1199                         break;
1200                 case Opt_lock:
1201                         mnt->flags &= ~NFS_MOUNT_NONLM;
1202                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1203                                         NFS_MOUNT_LOCAL_FCNTL);
1204                         break;
1205                 case Opt_nolock:
1206                         mnt->flags |= NFS_MOUNT_NONLM;
1207                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1208                                        NFS_MOUNT_LOCAL_FCNTL);
1209                         break;
1210                 case Opt_udp:
1211                         mnt->flags &= ~NFS_MOUNT_TCP;
1212                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1213                         break;
1214                 case Opt_tcp:
1215                         mnt->flags |= NFS_MOUNT_TCP;
1216                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1217                         break;
1218                 case Opt_rdma:
1219                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1220                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1221                         xprt_load_transport(p);
1222                         break;
1223                 case Opt_acl:
1224                         mnt->flags &= ~NFS_MOUNT_NOACL;
1225                         break;
1226                 case Opt_noacl:
1227                         mnt->flags |= NFS_MOUNT_NOACL;
1228                         break;
1229                 case Opt_rdirplus:
1230                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1231                         break;
1232                 case Opt_nordirplus:
1233                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1234                         break;
1235                 case Opt_sharecache:
1236                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1237                         break;
1238                 case Opt_nosharecache:
1239                         mnt->flags |= NFS_MOUNT_UNSHARED;
1240                         break;
1241                 case Opt_resvport:
1242                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1243                         break;
1244                 case Opt_noresvport:
1245                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1246                         break;
1247                 case Opt_fscache:
1248                         mnt->options |= NFS_OPTION_FSCACHE;
1249                         kfree(mnt->fscache_uniq);
1250                         mnt->fscache_uniq = NULL;
1251                         break;
1252                 case Opt_nofscache:
1253                         mnt->options &= ~NFS_OPTION_FSCACHE;
1254                         kfree(mnt->fscache_uniq);
1255                         mnt->fscache_uniq = NULL;
1256                         break;
1257                 case Opt_migration:
1258                         mnt->options |= NFS_OPTION_MIGRATION;
1259                         break;
1260                 case Opt_nomigration:
1261                         mnt->options &= NFS_OPTION_MIGRATION;
1262                         break;
1263
1264                 /*
1265                  * options that take numeric values
1266                  */
1267                 case Opt_port:
1268                         if (nfs_get_option_ul(args, &option) ||
1269                             option > USHRT_MAX)
1270                                 goto out_invalid_value;
1271                         mnt->nfs_server.port = option;
1272                         break;
1273                 case Opt_rsize:
1274                         if (nfs_get_option_ul(args, &option))
1275                                 goto out_invalid_value;
1276                         mnt->rsize = option;
1277                         break;
1278                 case Opt_wsize:
1279                         if (nfs_get_option_ul(args, &option))
1280                                 goto out_invalid_value;
1281                         mnt->wsize = option;
1282                         break;
1283                 case Opt_bsize:
1284                         if (nfs_get_option_ul(args, &option))
1285                                 goto out_invalid_value;
1286                         mnt->bsize = option;
1287                         break;
1288                 case Opt_timeo:
1289                         if (nfs_get_option_ul(args, &option) || option == 0)
1290                                 goto out_invalid_value;
1291                         mnt->timeo = option;
1292                         break;
1293                 case Opt_retrans:
1294                         if (nfs_get_option_ul(args, &option) || option == 0)
1295                                 goto out_invalid_value;
1296                         mnt->retrans = option;
1297                         break;
1298                 case Opt_acregmin:
1299                         if (nfs_get_option_ul(args, &option))
1300                                 goto out_invalid_value;
1301                         mnt->acregmin = option;
1302                         break;
1303                 case Opt_acregmax:
1304                         if (nfs_get_option_ul(args, &option))
1305                                 goto out_invalid_value;
1306                         mnt->acregmax = option;
1307                         break;
1308                 case Opt_acdirmin:
1309                         if (nfs_get_option_ul(args, &option))
1310                                 goto out_invalid_value;
1311                         mnt->acdirmin = option;
1312                         break;
1313                 case Opt_acdirmax:
1314                         if (nfs_get_option_ul(args, &option))
1315                                 goto out_invalid_value;
1316                         mnt->acdirmax = option;
1317                         break;
1318                 case Opt_actimeo:
1319                         if (nfs_get_option_ul(args, &option))
1320                                 goto out_invalid_value;
1321                         mnt->acregmin = mnt->acregmax =
1322                         mnt->acdirmin = mnt->acdirmax = option;
1323                         break;
1324                 case Opt_namelen:
1325                         if (nfs_get_option_ul(args, &option))
1326                                 goto out_invalid_value;
1327                         mnt->namlen = option;
1328                         break;
1329                 case Opt_mountport:
1330                         if (nfs_get_option_ul(args, &option) ||
1331                             option > USHRT_MAX)
1332                                 goto out_invalid_value;
1333                         mnt->mount_server.port = option;
1334                         break;
1335                 case Opt_mountvers:
1336                         if (nfs_get_option_ul(args, &option) ||
1337                             option < NFS_MNT_VERSION ||
1338                             option > NFS_MNT3_VERSION)
1339                                 goto out_invalid_value;
1340                         mnt->mount_server.version = option;
1341                         break;
1342                 case Opt_minorversion:
1343                         if (nfs_get_option_ul(args, &option))
1344                                 goto out_invalid_value;
1345                         if (option > NFS4_MAX_MINOR_VERSION)
1346                                 goto out_invalid_value;
1347                         mnt->minorversion = option;
1348                         break;
1349
1350                 /*
1351                  * options that take text values
1352                  */
1353                 case Opt_nfsvers:
1354                         string = match_strdup(args);
1355                         if (string == NULL)
1356                                 goto out_nomem;
1357                         rc = nfs_parse_version_string(string, mnt, args);
1358                         kfree(string);
1359                         if (!rc)
1360                                 goto out_invalid_value;
1361                         break;
1362                 case Opt_sec:
1363                         string = match_strdup(args);
1364                         if (string == NULL)
1365                                 goto out_nomem;
1366                         rc = nfs_parse_security_flavors(string, mnt);
1367                         kfree(string);
1368                         if (!rc) {
1369                                 dfprintk(MOUNT, "NFS:   unrecognized "
1370                                                 "security flavor\n");
1371                                 return 0;
1372                         }
1373                         break;
1374                 case Opt_proto:
1375                         string = match_strdup(args);
1376                         if (string == NULL)
1377                                 goto out_nomem;
1378                         token = match_token(string,
1379                                             nfs_xprt_protocol_tokens, args);
1380
1381                         protofamily = AF_INET;
1382                         switch (token) {
1383                         case Opt_xprt_udp6:
1384                                 protofamily = AF_INET6;
1385                         case Opt_xprt_udp:
1386                                 mnt->flags &= ~NFS_MOUNT_TCP;
1387                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1388                                 break;
1389                         case Opt_xprt_tcp6:
1390                                 protofamily = AF_INET6;
1391                         case Opt_xprt_tcp:
1392                                 mnt->flags |= NFS_MOUNT_TCP;
1393                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1394                                 break;
1395                         case Opt_xprt_rdma:
1396                                 /* vector side protocols to TCP */
1397                                 mnt->flags |= NFS_MOUNT_TCP;
1398                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1399                                 xprt_load_transport(string);
1400                                 break;
1401                         default:
1402                                 dfprintk(MOUNT, "NFS:   unrecognized "
1403                                                 "transport protocol\n");
1404                                 kfree(string);
1405                                 return 0;
1406                         }
1407                         kfree(string);
1408                         break;
1409                 case Opt_mountproto:
1410                         string = match_strdup(args);
1411                         if (string == NULL)
1412                                 goto out_nomem;
1413                         token = match_token(string,
1414                                             nfs_xprt_protocol_tokens, args);
1415                         kfree(string);
1416
1417                         mountfamily = AF_INET;
1418                         switch (token) {
1419                         case Opt_xprt_udp6:
1420                                 mountfamily = AF_INET6;
1421                         case Opt_xprt_udp:
1422                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1423                                 break;
1424                         case Opt_xprt_tcp6:
1425                                 mountfamily = AF_INET6;
1426                         case Opt_xprt_tcp:
1427                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1428                                 break;
1429                         case Opt_xprt_rdma: /* not used for side protocols */
1430                         default:
1431                                 dfprintk(MOUNT, "NFS:   unrecognized "
1432                                                 "transport protocol\n");
1433                                 return 0;
1434                         }
1435                         break;
1436                 case Opt_addr:
1437                         string = match_strdup(args);
1438                         if (string == NULL)
1439                                 goto out_nomem;
1440                         mnt->nfs_server.addrlen =
1441                                 rpc_pton(mnt->net, string, strlen(string),
1442                                         (struct sockaddr *)
1443                                         &mnt->nfs_server.address,
1444                                         sizeof(mnt->nfs_server.address));
1445                         kfree(string);
1446                         if (mnt->nfs_server.addrlen == 0)
1447                                 goto out_invalid_address;
1448                         break;
1449                 case Opt_clientaddr:
1450                         if (nfs_get_option_str(args, &mnt->client_address))
1451                                 goto out_nomem;
1452                         break;
1453                 case Opt_mounthost:
1454                         if (nfs_get_option_str(args,
1455                                                &mnt->mount_server.hostname))
1456                                 goto out_nomem;
1457                         break;
1458                 case Opt_mountaddr:
1459                         string = match_strdup(args);
1460                         if (string == NULL)
1461                                 goto out_nomem;
1462                         mnt->mount_server.addrlen =
1463                                 rpc_pton(mnt->net, string, strlen(string),
1464                                         (struct sockaddr *)
1465                                         &mnt->mount_server.address,
1466                                         sizeof(mnt->mount_server.address));
1467                         kfree(string);
1468                         if (mnt->mount_server.addrlen == 0)
1469                                 goto out_invalid_address;
1470                         break;
1471                 case Opt_lookupcache:
1472                         string = match_strdup(args);
1473                         if (string == NULL)
1474                                 goto out_nomem;
1475                         token = match_token(string,
1476                                         nfs_lookupcache_tokens, args);
1477                         kfree(string);
1478                         switch (token) {
1479                                 case Opt_lookupcache_all:
1480                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1481                                         break;
1482                                 case Opt_lookupcache_positive:
1483                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1484                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1485                                         break;
1486                                 case Opt_lookupcache_none:
1487                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1488                                         break;
1489                                 default:
1490                                         dfprintk(MOUNT, "NFS:   invalid "
1491                                                         "lookupcache argument\n");
1492                                         return 0;
1493                         };
1494                         break;
1495                 case Opt_fscache_uniq:
1496                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1497                                 goto out_nomem;
1498                         mnt->options |= NFS_OPTION_FSCACHE;
1499                         break;
1500                 case Opt_local_lock:
1501                         string = match_strdup(args);
1502                         if (string == NULL)
1503                                 goto out_nomem;
1504                         token = match_token(string, nfs_local_lock_tokens,
1505                                         args);
1506                         kfree(string);
1507                         switch (token) {
1508                         case Opt_local_lock_all:
1509                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1510                                                NFS_MOUNT_LOCAL_FCNTL);
1511                                 break;
1512                         case Opt_local_lock_flock:
1513                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1514                                 break;
1515                         case Opt_local_lock_posix:
1516                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1517                                 break;
1518                         case Opt_local_lock_none:
1519                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1520                                                 NFS_MOUNT_LOCAL_FCNTL);
1521                                 break;
1522                         default:
1523                                 dfprintk(MOUNT, "NFS:   invalid "
1524                                                 "local_lock argument\n");
1525                                 return 0;
1526                         };
1527                         break;
1528
1529                 /*
1530                  * Special options
1531                  */
1532                 case Opt_sloppy:
1533                         sloppy = 1;
1534                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1535                         break;
1536                 case Opt_userspace:
1537                 case Opt_deprecated:
1538                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1539                                         "'%s'\n", p);
1540                         break;
1541
1542                 default:
1543                         invalid_option = 1;
1544                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1545                                         "'%s'\n", p);
1546                 }
1547         }
1548
1549         if (!sloppy && invalid_option)
1550                 return 0;
1551
1552         if (mnt->minorversion && mnt->version != 4)
1553                 goto out_minorversion_mismatch;
1554
1555         if (mnt->options & NFS_OPTION_MIGRATION &&
1556             mnt->version != 4 && mnt->minorversion != 0)
1557                 goto out_migration_misuse;
1558
1559         /*
1560          * verify that any proto=/mountproto= options match the address
1561          * families in the addr=/mountaddr= options.
1562          */
1563         if (protofamily != AF_UNSPEC &&
1564             protofamily != mnt->nfs_server.address.ss_family)
1565                 goto out_proto_mismatch;
1566
1567         if (mountfamily != AF_UNSPEC) {
1568                 if (mnt->mount_server.addrlen) {
1569                         if (mountfamily != mnt->mount_server.address.ss_family)
1570                                 goto out_mountproto_mismatch;
1571                 } else {
1572                         if (mountfamily != mnt->nfs_server.address.ss_family)
1573                                 goto out_mountproto_mismatch;
1574                 }
1575         }
1576
1577         return 1;
1578
1579 out_mountproto_mismatch:
1580         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1581                          "option\n");
1582         return 0;
1583 out_proto_mismatch:
1584         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1585         return 0;
1586 out_invalid_address:
1587         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1588         return 0;
1589 out_invalid_value:
1590         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1591         return 0;
1592 out_minorversion_mismatch:
1593         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1594                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1595         return 0;
1596 out_migration_misuse:
1597         printk(KERN_INFO
1598                 "NFS: 'migration' not supported for this NFS version\n");
1599         return 0;
1600 out_nomem:
1601         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1602         return 0;
1603 out_security_failure:
1604         free_secdata(secdata);
1605         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1606         return 0;
1607 }
1608
1609 /*
1610  * Match the requested auth flavors with the list returned by
1611  * the server.  Returns zero and sets the mount's authentication
1612  * flavor on success; returns -EACCES if server does not support
1613  * the requested flavor.
1614  */
1615 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1616                              struct nfs_mount_request *request)
1617 {
1618         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1619
1620         /*
1621          * Certain releases of Linux's mountd return an empty
1622          * flavor list.  To prevent behavioral regression with
1623          * these servers (ie. rejecting mounts that used to
1624          * succeed), revert to pre-2.6.32 behavior (no checking)
1625          * if the returned flavor list is empty.
1626          */
1627         if (server_authlist_len == 0)
1628                 return 0;
1629
1630         /*
1631          * We avoid sophisticated negotiating here, as there are
1632          * plenty of cases where we can get it wrong, providing
1633          * either too little or too much security.
1634          *
1635          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1636          * flavor listed first.  However, some servers list
1637          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1638          * preferred default, in args->auth_flavors[0] if user
1639          * didn't specify sec= mount option.
1640          */
1641         for (i = 0; i < args->auth_flavor_len; i++)
1642                 for (j = 0; j < server_authlist_len; j++)
1643                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1644                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1645                                         request->auth_flavs[j]);
1646                                 args->auth_flavors[0] = request->auth_flavs[j];
1647                                 return 0;
1648                         }
1649
1650         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1651         nfs_umount(request);
1652         return -EACCES;
1653 }
1654
1655 /*
1656  * Use the remote server's MOUNT service to request the NFS file handle
1657  * corresponding to the provided path.
1658  */
1659 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1660                              struct nfs_fh *root_fh)
1661 {
1662         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1663         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1664         struct nfs_mount_request request = {
1665                 .sap            = (struct sockaddr *)
1666                                                 &args->mount_server.address,
1667                 .dirpath        = args->nfs_server.export_path,
1668                 .protocol       = args->mount_server.protocol,
1669                 .fh             = root_fh,
1670                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1671                 .auth_flav_len  = &server_authlist_len,
1672                 .auth_flavs     = server_authlist,
1673                 .net            = args->net,
1674         };
1675         int status;
1676
1677         if (args->mount_server.version == 0) {
1678                 switch (args->version) {
1679                         default:
1680                                 args->mount_server.version = NFS_MNT3_VERSION;
1681                                 break;
1682                         case 2:
1683                                 args->mount_server.version = NFS_MNT_VERSION;
1684                 }
1685         }
1686         request.version = args->mount_server.version;
1687
1688         if (args->mount_server.hostname)
1689                 request.hostname = args->mount_server.hostname;
1690         else
1691                 request.hostname = args->nfs_server.hostname;
1692
1693         /*
1694          * Construct the mount server's address.
1695          */
1696         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1697                 memcpy(request.sap, &args->nfs_server.address,
1698                        args->nfs_server.addrlen);
1699                 args->mount_server.addrlen = args->nfs_server.addrlen;
1700         }
1701         request.salen = args->mount_server.addrlen;
1702         nfs_set_port(request.sap, &args->mount_server.port, 0);
1703
1704         /*
1705          * Now ask the mount server to map our export path
1706          * to a file handle.
1707          */
1708         status = nfs_mount(&request);
1709         if (status != 0) {
1710                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1711                                 request.hostname, status);
1712                 return status;
1713         }
1714
1715         /*
1716          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1717          */
1718         if (args->mount_server.version != NFS_MNT3_VERSION)
1719                 return 0;
1720         return nfs_walk_authlist(args, &request);
1721 }
1722
1723 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1724                              struct nfs_mount_info *mount_info,
1725                              struct nfs_subversion *nfs_mod)
1726 {
1727         int status;
1728         struct nfs_server *server;
1729
1730         if (mount_info->parsed->need_mount) {
1731                 status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1732                 if (status)
1733                         return ERR_PTR(status);
1734         }
1735
1736         /* Get a volume representation */
1737         server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1738         if (IS_ERR(server))
1739                 return ERR_CAST(server);
1740
1741         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1742 }
1743 EXPORT_SYMBOL_GPL(nfs_try_mount);
1744
1745 /*
1746  * Split "dev_name" into "hostname:export_path".
1747  *
1748  * The leftmost colon demarks the split between the server's hostname
1749  * and the export path.  If the hostname starts with a left square
1750  * bracket, then it may contain colons.
1751  *
1752  * Note: caller frees hostname and export path, even on error.
1753  */
1754 static int nfs_parse_devname(const char *dev_name,
1755                              char **hostname, size_t maxnamlen,
1756                              char **export_path, size_t maxpathlen)
1757 {
1758         size_t len;
1759         char *end;
1760
1761         /* Is the host name protected with square brakcets? */
1762         if (*dev_name == '[') {
1763                 end = strchr(++dev_name, ']');
1764                 if (end == NULL || end[1] != ':')
1765                         goto out_bad_devname;
1766
1767                 len = end - dev_name;
1768                 end++;
1769         } else {
1770                 char *comma;
1771
1772                 end = strchr(dev_name, ':');
1773                 if (end == NULL)
1774                         goto out_bad_devname;
1775                 len = end - dev_name;
1776
1777                 /* kill possible hostname list: not supported */
1778                 comma = strchr(dev_name, ',');
1779                 if (comma != NULL && comma < end)
1780                         *comma = 0;
1781         }
1782
1783         if (len > maxnamlen)
1784                 goto out_hostname;
1785
1786         /* N.B. caller will free nfs_server.hostname in all cases */
1787         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1788         if (*hostname == NULL)
1789                 goto out_nomem;
1790         len = strlen(++end);
1791         if (len > maxpathlen)
1792                 goto out_path;
1793         *export_path = kstrndup(end, len, GFP_KERNEL);
1794         if (!*export_path)
1795                 goto out_nomem;
1796
1797         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1798         return 0;
1799
1800 out_bad_devname:
1801         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1802         return -EINVAL;
1803
1804 out_nomem:
1805         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1806         return -ENOMEM;
1807
1808 out_hostname:
1809         dfprintk(MOUNT, "NFS: server hostname too long\n");
1810         return -ENAMETOOLONG;
1811
1812 out_path:
1813         dfprintk(MOUNT, "NFS: export pathname too long\n");
1814         return -ENAMETOOLONG;
1815 }
1816
1817 /*
1818  * Validate the NFS2/NFS3 mount data
1819  * - fills in the mount root filehandle
1820  *
1821  * For option strings, user space handles the following behaviors:
1822  *
1823  * + DNS: mapping server host name to IP address ("addr=" option)
1824  *
1825  * + failure mode: how to behave if a mount request can't be handled
1826  *   immediately ("fg/bg" option)
1827  *
1828  * + retry: how often to retry a mount request ("retry=" option)
1829  *
1830  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1831  *   mountproto=tcp after mountproto=udp, and so on
1832  */
1833 static int nfs23_validate_mount_data(void *options,
1834                                      struct nfs_parsed_mount_data *args,
1835                                      struct nfs_fh *mntfh,
1836                                      const char *dev_name)
1837 {
1838         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1839         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1840
1841         if (data == NULL)
1842                 goto out_no_data;
1843
1844         args->version = NFS_DEFAULT_VERSION;
1845         switch (data->version) {
1846         case 1:
1847                 data->namlen = 0;
1848         case 2:
1849                 data->bsize = 0;
1850         case 3:
1851                 if (data->flags & NFS_MOUNT_VER3)
1852                         goto out_no_v3;
1853                 data->root.size = NFS2_FHSIZE;
1854                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1855         case 4:
1856                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1857                         goto out_no_sec;
1858         case 5:
1859                 memset(data->context, 0, sizeof(data->context));
1860         case 6:
1861                 if (data->flags & NFS_MOUNT_VER3) {
1862                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1863                                 goto out_invalid_fh;
1864                         mntfh->size = data->root.size;
1865                         args->version = 3;
1866                 } else {
1867                         mntfh->size = NFS2_FHSIZE;
1868                         args->version = 2;
1869                 }
1870
1871
1872                 memcpy(mntfh->data, data->root.data, mntfh->size);
1873                 if (mntfh->size < sizeof(mntfh->data))
1874                         memset(mntfh->data + mntfh->size, 0,
1875                                sizeof(mntfh->data) - mntfh->size);
1876
1877                 /*
1878                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1879                  * can deal with.
1880                  */
1881                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1882                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1883                 args->rsize             = data->rsize;
1884                 args->wsize             = data->wsize;
1885                 args->timeo             = data->timeo;
1886                 args->retrans           = data->retrans;
1887                 args->acregmin          = data->acregmin;
1888                 args->acregmax          = data->acregmax;
1889                 args->acdirmin          = data->acdirmin;
1890                 args->acdirmax          = data->acdirmax;
1891                 args->need_mount        = false;
1892
1893                 memcpy(sap, &data->addr, sizeof(data->addr));
1894                 args->nfs_server.addrlen = sizeof(data->addr);
1895                 args->nfs_server.port = ntohs(data->addr.sin_port);
1896                 if (!nfs_verify_server_address(sap))
1897                         goto out_no_address;
1898
1899                 if (!(data->flags & NFS_MOUNT_TCP))
1900                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1901                 /* N.B. caller will free nfs_server.hostname in all cases */
1902                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1903                 args->namlen            = data->namlen;
1904                 args->bsize             = data->bsize;
1905
1906                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1907                         args->auth_flavors[0] = data->pseudoflavor;
1908                 if (!args->nfs_server.hostname)
1909                         goto out_nomem;
1910
1911                 if (!(data->flags & NFS_MOUNT_NONLM))
1912                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1913                                          NFS_MOUNT_LOCAL_FCNTL);
1914                 else
1915                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1916                                         NFS_MOUNT_LOCAL_FCNTL);
1917                 /*
1918                  * The legacy version 6 binary mount data from userspace has a
1919                  * field used only to transport selinux information into the
1920                  * the kernel.  To continue to support that functionality we
1921                  * have a touch of selinux knowledge here in the NFS code. The
1922                  * userspace code converted context=blah to just blah so we are
1923                  * converting back to the full string selinux understands.
1924                  */
1925                 if (data->context[0]){
1926 #ifdef CONFIG_SECURITY_SELINUX
1927                         int rc;
1928                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1929                         if (!opts_str)
1930                                 return -ENOMEM;
1931                         strcpy(opts_str, "context=");
1932                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1933                         strcat(opts_str, &data->context[0]);
1934                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1935                         kfree(opts_str);
1936                         if (rc)
1937                                 return rc;
1938 #else
1939                         return -EINVAL;
1940 #endif
1941                 }
1942
1943                 break;
1944         default:
1945                 return NFS_TEXT_DATA;
1946         }
1947
1948 #if !IS_ENABLED(CONFIG_NFS_V3)
1949         if (args->version == 3)
1950                 goto out_v3_not_compiled;
1951 #endif /* !CONFIG_NFS_V3 */
1952
1953         return 0;
1954
1955 out_no_data:
1956         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1957         return -EINVAL;
1958
1959 out_no_v3:
1960         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1961                  data->version);
1962         return -EINVAL;
1963
1964 out_no_sec:
1965         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1966         return -EINVAL;
1967
1968 #if !IS_ENABLED(CONFIG_NFS_V3)
1969 out_v3_not_compiled:
1970         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1971         return -EPROTONOSUPPORT;
1972 #endif /* !CONFIG_NFS_V3 */
1973
1974 out_nomem:
1975         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1976         return -ENOMEM;
1977
1978 out_no_address:
1979         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1980         return -EINVAL;
1981
1982 out_invalid_fh:
1983         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1984         return -EINVAL;
1985 }
1986
1987 #if IS_ENABLED(CONFIG_NFS_V4)
1988 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1989                                    void *options,
1990                                    struct nfs_parsed_mount_data *args,
1991                                    struct nfs_fh *mntfh,
1992                                    const char *dev_name)
1993 {
1994         if (fs_type == &nfs_fs_type)
1995                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1996         return nfs4_validate_mount_data(options, args, dev_name);
1997 }
1998 #else
1999 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2000                                    void *options,
2001                                    struct nfs_parsed_mount_data *args,
2002                                    struct nfs_fh *mntfh,
2003                                    const char *dev_name)
2004 {
2005         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2006 }
2007 #endif
2008
2009 static int nfs_validate_text_mount_data(void *options,
2010                                         struct nfs_parsed_mount_data *args,
2011                                         const char *dev_name)
2012 {
2013         int port = 0;
2014         int max_namelen = PAGE_SIZE;
2015         int max_pathlen = NFS_MAXPATHLEN;
2016         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2017
2018         if (nfs_parse_mount_options((char *)options, args) == 0)
2019                 return -EINVAL;
2020
2021         if (!nfs_verify_server_address(sap))
2022                 goto out_no_address;
2023
2024         if (args->version == 4) {
2025 #if IS_ENABLED(CONFIG_NFS_V4)
2026                 port = NFS_PORT;
2027                 max_namelen = NFS4_MAXNAMLEN;
2028                 max_pathlen = NFS4_MAXPATHLEN;
2029                 nfs_validate_transport_protocol(args);
2030                 nfs4_validate_mount_flags(args);
2031 #else
2032                 goto out_v4_not_compiled;
2033 #endif /* CONFIG_NFS_V4 */
2034         } else
2035                 nfs_set_mount_transport_protocol(args);
2036
2037         nfs_set_port(sap, &args->nfs_server.port, port);
2038
2039         if (args->auth_flavor_len > 1)
2040                 goto out_bad_auth;
2041
2042         return nfs_parse_devname(dev_name,
2043                                    &args->nfs_server.hostname,
2044                                    max_namelen,
2045                                    &args->nfs_server.export_path,
2046                                    max_pathlen);
2047
2048 #if !IS_ENABLED(CONFIG_NFS_V4)
2049 out_v4_not_compiled:
2050         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2051         return -EPROTONOSUPPORT;
2052 #endif /* !CONFIG_NFS_V4 */
2053
2054 out_no_address:
2055         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2056         return -EINVAL;
2057
2058 out_bad_auth:
2059         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2060         return -EINVAL;
2061 }
2062
2063 static int
2064 nfs_compare_remount_data(struct nfs_server *nfss,
2065                          struct nfs_parsed_mount_data *data)
2066 {
2067         if (data->flags != nfss->flags ||
2068             data->rsize != nfss->rsize ||
2069             data->wsize != nfss->wsize ||
2070             data->retrans != nfss->client->cl_timeout->to_retries ||
2071             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2072             data->acregmin != nfss->acregmin / HZ ||
2073             data->acregmax != nfss->acregmax / HZ ||
2074             data->acdirmin != nfss->acdirmin / HZ ||
2075             data->acdirmax != nfss->acdirmax / HZ ||
2076             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2077             data->nfs_server.port != nfss->port ||
2078             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2079             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2080                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2081                 return -EINVAL;
2082
2083         return 0;
2084 }
2085
2086 int
2087 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2088 {
2089         int error;
2090         struct nfs_server *nfss = sb->s_fs_info;
2091         struct nfs_parsed_mount_data *data;
2092         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2093         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2094         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2095
2096         /*
2097          * Userspace mount programs that send binary options generally send
2098          * them populated with default values. We have no way to know which
2099          * ones were explicitly specified. Fall back to legacy behavior and
2100          * just return success.
2101          */
2102         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2103             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2104                                            options->version <= 6))))
2105                 return 0;
2106
2107         data = kzalloc(sizeof(*data), GFP_KERNEL);
2108         if (data == NULL)
2109                 return -ENOMEM;
2110
2111         /* fill out struct with values from existing mount */
2112         data->flags = nfss->flags;
2113         data->rsize = nfss->rsize;
2114         data->wsize = nfss->wsize;
2115         data->retrans = nfss->client->cl_timeout->to_retries;
2116         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2117         data->acregmin = nfss->acregmin / HZ;
2118         data->acregmax = nfss->acregmax / HZ;
2119         data->acdirmin = nfss->acdirmin / HZ;
2120         data->acdirmax = nfss->acdirmax / HZ;
2121         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2122         data->nfs_server.port = nfss->port;
2123         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2124         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2125                 data->nfs_server.addrlen);
2126
2127         /* overwrite those values with any that were specified */
2128         error = nfs_parse_mount_options((char *)options, data);
2129         if (error < 0)
2130                 goto out;
2131
2132         /*
2133          * noac is a special case. It implies -o sync, but that's not
2134          * necessarily reflected in the mtab options. do_remount_sb
2135          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2136          * remount options, so we have to explicitly reset it.
2137          */
2138         if (data->flags & NFS_MOUNT_NOAC)
2139                 *flags |= MS_SYNCHRONOUS;
2140
2141         /* compare new mount options with old ones */
2142         error = nfs_compare_remount_data(nfss, data);
2143 out:
2144         kfree(data);
2145         return error;
2146 }
2147 EXPORT_SYMBOL_GPL(nfs_remount);
2148
2149 /*
2150  * Initialise the common bits of the superblock
2151  */
2152 inline void nfs_initialise_sb(struct super_block *sb)
2153 {
2154         struct nfs_server *server = NFS_SB(sb);
2155
2156         sb->s_magic = NFS_SUPER_MAGIC;
2157
2158         /* We probably want something more informative here */
2159         snprintf(sb->s_id, sizeof(sb->s_id),
2160                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2161
2162         if (sb->s_blocksize == 0)
2163                 sb->s_blocksize = nfs_block_bits(server->wsize,
2164                                                  &sb->s_blocksize_bits);
2165
2166         sb->s_bdi = &server->backing_dev_info;
2167
2168         nfs_super_set_maxbytes(sb, server->maxfilesize);
2169 }
2170
2171 /*
2172  * Finish setting up an NFS2/3 superblock
2173  */
2174 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2175 {
2176         struct nfs_parsed_mount_data *data = mount_info->parsed;
2177         struct nfs_server *server = NFS_SB(sb);
2178
2179         sb->s_blocksize_bits = 0;
2180         sb->s_blocksize = 0;
2181         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2182         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2183         if (data && data->bsize)
2184                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2185
2186         if (server->nfs_client->rpc_ops->version != 2) {
2187                 /* The VFS shouldn't apply the umask to mode bits. We will do
2188                  * so ourselves when necessary.
2189                  */
2190                 sb->s_flags |= MS_POSIXACL;
2191                 sb->s_time_gran = 1;
2192         }
2193
2194         nfs_initialise_sb(sb);
2195 }
2196 EXPORT_SYMBOL_GPL(nfs_fill_super);
2197
2198 /*
2199  * Finish setting up a cloned NFS2/3/4 superblock
2200  */
2201 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2202 {
2203         const struct super_block *old_sb = mount_info->cloned->sb;
2204         struct nfs_server *server = NFS_SB(sb);
2205
2206         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2207         sb->s_blocksize = old_sb->s_blocksize;
2208         sb->s_maxbytes = old_sb->s_maxbytes;
2209         sb->s_xattr = old_sb->s_xattr;
2210         sb->s_op = old_sb->s_op;
2211         sb->s_time_gran = 1;
2212
2213         if (server->nfs_client->rpc_ops->version != 2) {
2214                 /* The VFS shouldn't apply the umask to mode bits. We will do
2215                  * so ourselves when necessary.
2216                  */
2217                 sb->s_flags |= MS_POSIXACL;
2218         }
2219
2220         nfs_initialise_sb(sb);
2221 }
2222
2223 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2224 {
2225         const struct nfs_server *a = s->s_fs_info;
2226         const struct rpc_clnt *clnt_a = a->client;
2227         const struct rpc_clnt *clnt_b = b->client;
2228
2229         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2230                 goto Ebusy;
2231         if (a->nfs_client != b->nfs_client)
2232                 goto Ebusy;
2233         if (a->flags != b->flags)
2234                 goto Ebusy;
2235         if (a->wsize != b->wsize)
2236                 goto Ebusy;
2237         if (a->rsize != b->rsize)
2238                 goto Ebusy;
2239         if (a->acregmin != b->acregmin)
2240                 goto Ebusy;
2241         if (a->acregmax != b->acregmax)
2242                 goto Ebusy;
2243         if (a->acdirmin != b->acdirmin)
2244                 goto Ebusy;
2245         if (a->acdirmax != b->acdirmax)
2246                 goto Ebusy;
2247         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2248                 goto Ebusy;
2249         return 1;
2250 Ebusy:
2251         return 0;
2252 }
2253
2254 struct nfs_sb_mountdata {
2255         struct nfs_server *server;
2256         int mntflags;
2257 };
2258
2259 static int nfs_set_super(struct super_block *s, void *data)
2260 {
2261         struct nfs_sb_mountdata *sb_mntdata = data;
2262         struct nfs_server *server = sb_mntdata->server;
2263         int ret;
2264
2265         s->s_flags = sb_mntdata->mntflags;
2266         s->s_fs_info = server;
2267         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2268         ret = set_anon_super(s, server);
2269         if (ret == 0)
2270                 server->s_dev = s->s_dev;
2271         return ret;
2272 }
2273
2274 static int nfs_compare_super_address(struct nfs_server *server1,
2275                                      struct nfs_server *server2)
2276 {
2277         struct sockaddr *sap1, *sap2;
2278
2279         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2280         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2281
2282         if (sap1->sa_family != sap2->sa_family)
2283                 return 0;
2284
2285         switch (sap1->sa_family) {
2286         case AF_INET: {
2287                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2288                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2289                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2290                         return 0;
2291                 if (sin1->sin_port != sin2->sin_port)
2292                         return 0;
2293                 break;
2294         }
2295         case AF_INET6: {
2296                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2297                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2298                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2299                         return 0;
2300                 if (sin1->sin6_port != sin2->sin6_port)
2301                         return 0;
2302                 break;
2303         }
2304         default:
2305                 return 0;
2306         }
2307
2308         return 1;
2309 }
2310
2311 static int nfs_compare_super(struct super_block *sb, void *data)
2312 {
2313         struct nfs_sb_mountdata *sb_mntdata = data;
2314         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2315         int mntflags = sb_mntdata->mntflags;
2316
2317         if (!nfs_compare_super_address(old, server))
2318                 return 0;
2319         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2320         if (old->flags & NFS_MOUNT_UNSHARED)
2321                 return 0;
2322         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2323                 return 0;
2324         return nfs_compare_mount_options(sb, server, mntflags);
2325 }
2326
2327 #ifdef CONFIG_NFS_FSCACHE
2328 static void nfs_get_cache_cookie(struct super_block *sb,
2329                                  struct nfs_parsed_mount_data *parsed,
2330                                  struct nfs_clone_mount *cloned)
2331 {
2332         struct nfs_server *nfss = NFS_SB(sb);
2333         char *uniq = NULL;
2334         int ulen = 0;
2335
2336         nfss->fscache_key = NULL;
2337         nfss->fscache = NULL;
2338
2339         if (parsed) {
2340                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2341                         return;
2342                 if (parsed->fscache_uniq) {
2343                         uniq = parsed->fscache_uniq;
2344                         ulen = strlen(parsed->fscache_uniq);
2345                 }
2346         } else if (cloned) {
2347                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2348                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2349                         return;
2350                 if (mnt_s->fscache_key) {
2351                         uniq = mnt_s->fscache_key->key.uniquifier;
2352                         ulen = mnt_s->fscache_key->key.uniq_len;
2353                 };
2354         } else
2355                 return;
2356
2357         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2358 }
2359 #else
2360 static void nfs_get_cache_cookie(struct super_block *sb,
2361                                  struct nfs_parsed_mount_data *parsed,
2362                                  struct nfs_clone_mount *cloned)
2363 {
2364 }
2365 #endif
2366
2367 static int nfs_bdi_register(struct nfs_server *server)
2368 {
2369         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2370 }
2371
2372 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2373                         struct nfs_mount_info *mount_info)
2374 {
2375         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2376 }
2377 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2378
2379 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2380                           struct nfs_mount_info *mount_info)
2381 {
2382         /* clone any lsm security options from the parent to the new sb */
2383         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2384         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2385                 return -ESTALE;
2386         return 0;
2387 }
2388 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2389
2390 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2391                                    int flags, const char *dev_name,
2392                                    struct nfs_mount_info *mount_info,
2393                                    struct nfs_subversion *nfs_mod)
2394 {
2395         struct super_block *s;
2396         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2397         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2398         struct nfs_sb_mountdata sb_mntdata = {
2399                 .mntflags = flags,
2400                 .server = server,
2401         };
2402         int error;
2403
2404         if (server->flags & NFS_MOUNT_UNSHARED)
2405                 compare_super = NULL;
2406
2407         /* -o noac implies -o sync */
2408         if (server->flags & NFS_MOUNT_NOAC)
2409                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2410
2411         /* Get a superblock - note that we may end up sharing one that already exists */
2412         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2413         if (IS_ERR(s)) {
2414                 mntroot = ERR_CAST(s);
2415                 goto out_err_nosb;
2416         }
2417
2418         if (s->s_fs_info != server) {
2419                 nfs_free_server(server);
2420                 server = NULL;
2421         } else {
2422                 error = nfs_bdi_register(server);
2423                 if (error) {
2424                         mntroot = ERR_PTR(error);
2425                         goto error_splat_bdi;
2426                 }
2427         }
2428
2429         if (!s->s_root) {
2430                 /* initial superblock/root creation */
2431                 mount_info->fill_super(s, mount_info);
2432                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2433         }
2434
2435         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2436         if (IS_ERR(mntroot))
2437                 goto error_splat_super;
2438
2439         error = mount_info->set_security(s, mntroot, mount_info);
2440         if (error)
2441                 goto error_splat_root;
2442
2443         s->s_flags |= MS_ACTIVE;
2444
2445 out:
2446         return mntroot;
2447
2448 out_err_nosb:
2449         nfs_free_server(server);
2450         goto out;
2451
2452 error_splat_root:
2453         dput(mntroot);
2454         mntroot = ERR_PTR(error);
2455 error_splat_super:
2456         if (server && !s->s_root)
2457                 bdi_unregister(&server->backing_dev_info);
2458 error_splat_bdi:
2459         deactivate_locked_super(s);
2460         goto out;
2461 }
2462 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2463
2464 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2465         int flags, const char *dev_name, void *raw_data)
2466 {
2467         struct nfs_mount_info mount_info = {
2468                 .fill_super = nfs_fill_super,
2469                 .set_security = nfs_set_sb_security,
2470         };
2471         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2472         struct nfs_subversion *nfs_mod;
2473         int error;
2474
2475         mount_info.parsed = nfs_alloc_parsed_mount_data();
2476         mount_info.mntfh = nfs_alloc_fhandle();
2477         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2478                 goto out;
2479
2480         /* Validate the mount data */
2481         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2482         if (error == NFS_TEXT_DATA)
2483                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2484         if (error < 0) {
2485                 mntroot = ERR_PTR(error);
2486                 goto out;
2487         }
2488
2489         nfs_mod = get_nfs_version(mount_info.parsed->version);
2490         if (IS_ERR(nfs_mod)) {
2491                 mntroot = ERR_CAST(nfs_mod);
2492                 goto out;
2493         }
2494
2495         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2496
2497         put_nfs_version(nfs_mod);
2498 out:
2499         nfs_free_parsed_mount_data(mount_info.parsed);
2500         nfs_free_fhandle(mount_info.mntfh);
2501         return mntroot;
2502 }
2503 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2504
2505 /*
2506  * Ensure that we unregister the bdi before kill_anon_super
2507  * releases the device name
2508  */
2509 void nfs_put_super(struct super_block *s)
2510 {
2511         struct nfs_server *server = NFS_SB(s);
2512
2513         bdi_unregister(&server->backing_dev_info);
2514 }
2515 EXPORT_SYMBOL_GPL(nfs_put_super);
2516
2517 /*
2518  * Destroy an NFS2/3 superblock
2519  */
2520 void nfs_kill_super(struct super_block *s)
2521 {
2522         struct nfs_server *server = NFS_SB(s);
2523
2524         kill_anon_super(s);
2525         nfs_fscache_release_super_cookie(s);
2526         nfs_free_server(server);
2527 }
2528 EXPORT_SYMBOL_GPL(nfs_kill_super);
2529
2530 /*
2531  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2532  */
2533 static struct dentry *
2534 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2535                 const char *dev_name, void *raw_data)
2536 {
2537         struct nfs_clone_mount *data = raw_data;
2538         struct nfs_mount_info mount_info = {
2539                 .fill_super = nfs_clone_super,
2540                 .set_security = nfs_clone_sb_security,
2541                 .cloned = data,
2542         };
2543         struct nfs_server *server;
2544         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2545         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2546
2547         dprintk("--> nfs_xdev_mount()\n");
2548
2549         mount_info.mntfh = mount_info.cloned->fh;
2550
2551         /* create a new volume representation */
2552         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2553
2554         if (IS_ERR(server))
2555                 mntroot = ERR_CAST(server);
2556         else
2557                 mntroot = nfs_fs_mount_common(server, flags,
2558                                 dev_name, &mount_info, nfs_mod);
2559
2560         dprintk("<-- nfs_xdev_mount() = %ld\n",
2561                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2562         return mntroot;
2563 }
2564
2565 #if IS_ENABLED(CONFIG_NFS_V4)
2566
2567 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2568 {
2569         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2570                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2571 }
2572
2573 /*
2574  * Validate NFSv4 mount options
2575  */
2576 static int nfs4_validate_mount_data(void *options,
2577                                     struct nfs_parsed_mount_data *args,
2578                                     const char *dev_name)
2579 {
2580         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2581         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2582         char *c;
2583
2584         if (data == NULL)
2585                 goto out_no_data;
2586
2587         args->version = 4;
2588
2589         switch (data->version) {
2590         case 1:
2591                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2592                         goto out_no_address;
2593                 if (data->host_addrlen == 0)
2594                         goto out_no_address;
2595                 args->nfs_server.addrlen = data->host_addrlen;
2596                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2597                         return -EFAULT;
2598                 if (!nfs_verify_server_address(sap))
2599                         goto out_no_address;
2600                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2601
2602                 if (data->auth_flavourlen) {
2603                         if (data->auth_flavourlen > 1)
2604                                 goto out_inval_auth;
2605                         if (copy_from_user(&args->auth_flavors[0],
2606                                            data->auth_flavours,
2607                                            sizeof(args->auth_flavors[0])))
2608                                 return -EFAULT;
2609                 }
2610
2611                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2612                 if (IS_ERR(c))
2613                         return PTR_ERR(c);
2614                 args->nfs_server.hostname = c;
2615
2616                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2617                 if (IS_ERR(c))
2618                         return PTR_ERR(c);
2619                 args->nfs_server.export_path = c;
2620                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2621
2622                 c = strndup_user(data->client_addr.data, 16);
2623                 if (IS_ERR(c))
2624                         return PTR_ERR(c);
2625                 args->client_address = c;
2626
2627                 /*
2628                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2629                  * can deal with.
2630                  */
2631
2632                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2633                 args->rsize     = data->rsize;
2634                 args->wsize     = data->wsize;
2635                 args->timeo     = data->timeo;
2636                 args->retrans   = data->retrans;
2637                 args->acregmin  = data->acregmin;
2638                 args->acregmax  = data->acregmax;
2639                 args->acdirmin  = data->acdirmin;
2640                 args->acdirmax  = data->acdirmax;
2641                 args->nfs_server.protocol = data->proto;
2642                 nfs_validate_transport_protocol(args);
2643
2644                 break;
2645         default:
2646                 return NFS_TEXT_DATA;
2647         }
2648
2649         return 0;
2650
2651 out_no_data:
2652         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2653         return -EINVAL;
2654
2655 out_inval_auth:
2656         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2657                  data->auth_flavourlen);
2658         return -EINVAL;
2659
2660 out_no_address:
2661         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2662         return -EINVAL;
2663 }
2664
2665 /*
2666  * NFS v4 module parameters need to stay in the
2667  * NFS client for backwards compatibility
2668  */
2669 unsigned int nfs_callback_set_tcpport;
2670 unsigned short nfs_callback_tcpport;
2671 /* Default cache timeout is 10 minutes */
2672 unsigned int nfs_idmap_cache_timeout = 600;
2673 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2674 bool nfs4_disable_idmapping = true;
2675 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2676 unsigned short send_implementation_id = 1;
2677 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2678
2679 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2680 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2681 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2682 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2683 EXPORT_SYMBOL_GPL(max_session_slots);
2684 EXPORT_SYMBOL_GPL(send_implementation_id);
2685 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2686
2687 #define NFS_CALLBACK_MAXPORTNR (65535U)
2688
2689 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2690 {
2691         unsigned long num;
2692         int ret;
2693
2694         if (!val)
2695                 return -EINVAL;
2696         ret = kstrtoul(val, 0, &num);
2697         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2698                 return -EINVAL;
2699         *((unsigned int *)kp->arg) = num;
2700         return 0;
2701 }
2702 static struct kernel_param_ops param_ops_portnr = {
2703         .set = param_set_portnr,
2704         .get = param_get_uint,
2705 };
2706 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2707
2708 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2709 module_param(nfs_idmap_cache_timeout, int, 0644);
2710 module_param(nfs4_disable_idmapping, bool, 0644);
2711 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2712                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2713 MODULE_PARM_DESC(nfs4_disable_idmapping,
2714                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2715 module_param(max_session_slots, ushort, 0644);
2716 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2717                 "requests the client will negotiate");
2718 module_param(send_implementation_id, ushort, 0644);
2719 MODULE_PARM_DESC(send_implementation_id,
2720                 "Send implementation ID with NFSv4.1 exchange_id");
2721 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2722
2723 #endif /* CONFIG_NFS_V4 */