fs/nfs/super.c

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