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.Cox@linux.org>, 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/smp_lock.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <net/ipv6.h>
  50 #include <linux/nfs_xdr.h>
  51 #include <linux/magic.h>
  52 #include <linux/parser.h>
  53
  54 #include <asm/system.h>
  55 #include <asm/uaccess.h>
  56
  57 #include "nfs4_fs.h"
  58 #include "callback.h"
  59 #include "delegation.h"
  60 #include "iostat.h"
  61 #include "internal.h"
  62
  63 #define NFSDBG_FACILITY         NFSDBG_VFS
  64
  65 enum {
  66         /* Mount options that take no arguments */
  67         Opt_soft, Opt_hard,
  68         Opt_posix, Opt_noposix,
  69         Opt_cto, Opt_nocto,
  70         Opt_ac, Opt_noac,
  71         Opt_lock, Opt_nolock,
  72         Opt_v2, Opt_v3,
  73         Opt_udp, Opt_tcp, Opt_rdma,
  74         Opt_acl, Opt_noacl,
  75         Opt_rdirplus, Opt_nordirplus,
  76         Opt_sharecache, Opt_nosharecache,
  77
  78         /* Mount options that take integer arguments */
  79         Opt_port,
  80         Opt_rsize, Opt_wsize, Opt_bsize,
  81         Opt_timeo, Opt_retrans,
  82         Opt_acregmin, Opt_acregmax,
  83         Opt_acdirmin, Opt_acdirmax,
  84         Opt_actimeo,
  85         Opt_namelen,
  86         Opt_mountport,
  87         Opt_mountvers,
  88         Opt_nfsvers,
  89
  90         /* Mount options that take string arguments */
  91         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
  92         Opt_addr, Opt_mountaddr, Opt_clientaddr,
  93
  94         /* Mount options that are ignored */
  95         Opt_userspace, Opt_deprecated,
  96
  97         Opt_err
  98 };
  99
 100 static match_table_t nfs_mount_option_tokens = {
 101         { Opt_userspace, "bg" },
 102         { Opt_userspace, "fg" },
 103         { Opt_userspace, "retry=%s" },
 104
 105         { Opt_soft, "soft" },
 106         { Opt_hard, "hard" },
 107         { Opt_deprecated, "intr" },
 108         { Opt_deprecated, "nointr" },
 109         { Opt_posix, "posix" },
 110         { Opt_noposix, "noposix" },
 111         { Opt_cto, "cto" },
 112         { Opt_nocto, "nocto" },
 113         { Opt_ac, "ac" },
 114         { Opt_noac, "noac" },
 115         { Opt_lock, "lock" },
 116         { Opt_nolock, "nolock" },
 117         { Opt_v2, "v2" },
 118         { Opt_v3, "v3" },
 119         { Opt_udp, "udp" },
 120         { Opt_tcp, "tcp" },
 121         { Opt_rdma, "rdma" },
 122         { Opt_acl, "acl" },
 123         { Opt_noacl, "noacl" },
 124         { Opt_rdirplus, "rdirplus" },
 125         { Opt_nordirplus, "nordirplus" },
 126         { Opt_sharecache, "sharecache" },
 127         { Opt_nosharecache, "nosharecache" },
 128
 129         { Opt_port, "port=%u" },
 130         { Opt_rsize, "rsize=%u" },
 131         { Opt_wsize, "wsize=%u" },
 132         { Opt_bsize, "bsize=%u" },
 133         { Opt_timeo, "timeo=%u" },
 134         { Opt_retrans, "retrans=%u" },
 135         { Opt_acregmin, "acregmin=%u" },
 136         { Opt_acregmax, "acregmax=%u" },
 137         { Opt_acdirmin, "acdirmin=%u" },
 138         { Opt_acdirmax, "acdirmax=%u" },
 139         { Opt_actimeo, "actimeo=%u" },
 140         { Opt_namelen, "namlen=%u" },
 141         { Opt_mountport, "mountport=%u" },
 142         { Opt_mountvers, "mountvers=%u" },
 143         { Opt_nfsvers, "nfsvers=%u" },
 144         { Opt_nfsvers, "vers=%u" },
 145
 146         { Opt_sec, "sec=%s" },
 147         { Opt_proto, "proto=%s" },
 148         { Opt_mountproto, "mountproto=%s" },
 149         { Opt_addr, "addr=%s" },
 150         { Opt_clientaddr, "clientaddr=%s" },
 151         { Opt_mounthost, "mounthost=%s" },
 152         { Opt_mountaddr, "mountaddr=%s" },
 153
 154         { Opt_err, NULL }
 155 };
 156
 157 enum {
 158         Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
 159
 160         Opt_xprt_err
 161 };
 162
 163 static match_table_t nfs_xprt_protocol_tokens = {
 164         { Opt_xprt_udp, "udp" },
 165         { Opt_xprt_tcp, "tcp" },
 166         { Opt_xprt_rdma, "rdma" },
 167
 168         { Opt_xprt_err, NULL }
 169 };
 170
 171 enum {
 172         Opt_sec_none, Opt_sec_sys,
 173         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 174         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 175         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 176
 177         Opt_sec_err
 178 };
 179
 180 static match_table_t nfs_secflavor_tokens = {
 181         { Opt_sec_none, "none" },
 182         { Opt_sec_none, "null" },
 183         { Opt_sec_sys, "sys" },
 184
 185         { Opt_sec_krb5, "krb5" },
 186         { Opt_sec_krb5i, "krb5i" },
 187         { Opt_sec_krb5p, "krb5p" },
 188
 189         { Opt_sec_lkey, "lkey" },
 190         { Opt_sec_lkeyi, "lkeyi" },
 191         { Opt_sec_lkeyp, "lkeyp" },
 192
 193         { Opt_sec_spkm, "spkm3" },
 194         { Opt_sec_spkmi, "spkm3i" },
 195         { Opt_sec_spkmp, "spkm3p" },
 196
 197         { Opt_sec_err, NULL }
 198 };
 199
 200
 201 static void nfs_umount_begin(struct super_block *);
 202 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 203 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 204 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 205 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 206 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 207                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 208 static void nfs_kill_super(struct super_block *);
 209 static void nfs_put_super(struct super_block *);
 210 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 211
 212 static struct file_system_type nfs_fs_type = {
 213         .owner          = THIS_MODULE,
 214         .name           = "nfs",
 215         .get_sb         = nfs_get_sb,
 216         .kill_sb        = nfs_kill_super,
 217         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 218 };
 219
 220 struct file_system_type nfs_xdev_fs_type = {
 221         .owner          = THIS_MODULE,
 222         .name           = "nfs",
 223         .get_sb         = nfs_xdev_get_sb,
 224         .kill_sb        = nfs_kill_super,
 225         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 226 };
 227
 228 static const struct super_operations nfs_sops = {
 229         .alloc_inode    = nfs_alloc_inode,
 230         .destroy_inode  = nfs_destroy_inode,
 231         .write_inode    = nfs_write_inode,
 232         .put_super      = nfs_put_super,
 233         .statfs         = nfs_statfs,
 234         .clear_inode    = nfs_clear_inode,
 235         .umount_begin   = nfs_umount_begin,
 236         .show_options   = nfs_show_options,
 237         .show_stats     = nfs_show_stats,
 238         .remount_fs     = nfs_remount,
 239 };
 240
 241 #ifdef CONFIG_NFS_V4
 242 static int nfs4_get_sb(struct file_system_type *fs_type,
 243         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 244 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 245         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 246 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 247         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 248 static void nfs4_kill_super(struct super_block *sb);
 249
 250 static struct file_system_type nfs4_fs_type = {
 251         .owner          = THIS_MODULE,
 252         .name           = "nfs4",
 253         .get_sb         = nfs4_get_sb,
 254         .kill_sb        = nfs4_kill_super,
 255         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 256 };
 257
 258 struct file_system_type nfs4_xdev_fs_type = {
 259         .owner          = THIS_MODULE,
 260         .name           = "nfs4",
 261         .get_sb         = nfs4_xdev_get_sb,
 262         .kill_sb        = nfs4_kill_super,
 263         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 264 };
 265
 266 struct file_system_type nfs4_referral_fs_type = {
 267         .owner          = THIS_MODULE,
 268         .name           = "nfs4",
 269         .get_sb         = nfs4_referral_get_sb,
 270         .kill_sb        = nfs4_kill_super,
 271         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 272 };
 273
 274 static const struct super_operations nfs4_sops = {
 275         .alloc_inode    = nfs_alloc_inode,
 276         .destroy_inode  = nfs_destroy_inode,
 277         .write_inode    = nfs_write_inode,
 278         .statfs         = nfs_statfs,
 279         .clear_inode    = nfs4_clear_inode,
 280         .umount_begin   = nfs_umount_begin,
 281         .show_options   = nfs_show_options,
 282         .show_stats     = nfs_show_stats,
 283         .remount_fs     = nfs_remount,
 284 };
 285 #endif
 286
 287 static struct shrinker acl_shrinker = {
 288         .shrink         = nfs_access_cache_shrinker,
 289         .seeks          = DEFAULT_SEEKS,
 290 };
 291
 292 /*
 293  * Register the NFS filesystems
 294  */
 295 int __init register_nfs_fs(void)
 296 {
 297         int ret;
 298
 299         ret = register_filesystem(&nfs_fs_type);
 300         if (ret < 0)
 301                 goto error_0;
 302
 303         ret = nfs_register_sysctl();
 304         if (ret < 0)
 305                 goto error_1;
 306 #ifdef CONFIG_NFS_V4
 307         ret = register_filesystem(&nfs4_fs_type);
 308         if (ret < 0)
 309                 goto error_2;
 310 #endif
 311         register_shrinker(&acl_shrinker);
 312         return 0;
 313
 314 #ifdef CONFIG_NFS_V4
 315 error_2:
 316         nfs_unregister_sysctl();
 317 #endif
 318 error_1:
 319         unregister_filesystem(&nfs_fs_type);
 320 error_0:
 321         return ret;
 322 }
 323
 324 /*
 325  * Unregister the NFS filesystems
 326  */
 327 void __exit unregister_nfs_fs(void)
 328 {
 329         unregister_shrinker(&acl_shrinker);
 330 #ifdef CONFIG_NFS_V4
 331         unregister_filesystem(&nfs4_fs_type);
 332 #endif
 333         nfs_unregister_sysctl();
 334         unregister_filesystem(&nfs_fs_type);
 335 }
 336
 337 void nfs_sb_active(struct nfs_server *server)
 338 {
 339         atomic_inc(&server->active);
 340 }
 341
 342 void nfs_sb_deactive(struct nfs_server *server)
 343 {
 344         if (atomic_dec_and_test(&server->active))
 345                 wake_up(&server->active_wq);
 346 }
 347
 348 static void nfs_put_super(struct super_block *sb)
 349 {
 350         struct nfs_server *server = NFS_SB(sb);
 351         /*
 352          * Make sure there are no outstanding ops to this server.
 353          * If so, wait for them to finish before allowing the
 354          * unmount to continue.
 355          */
 356         wait_event(server->active_wq, atomic_read(&server->active) == 0);
 357 }
 358
 359 /*
 360  * Deliver file system statistics to userspace
 361  */
 362 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 363 {
 364         struct nfs_server *server = NFS_SB(dentry->d_sb);
 365         unsigned char blockbits;
 366         unsigned long blockres;
 367         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 368         struct nfs_fattr fattr;
 369         struct nfs_fsstat res = {
 370                         .fattr = &fattr,
 371         };
 372         int error;
 373
 374         lock_kernel();
 375
 376         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 377         if (error < 0)
 378                 goto out_err;
 379         buf->f_type = NFS_SUPER_MAGIC;
 380
 381         /*
 382          * Current versions of glibc do not correctly handle the
 383          * case where f_frsize != f_bsize.  Eventually we want to
 384          * report the value of wtmult in this field.
 385          */
 386         buf->f_frsize = dentry->d_sb->s_blocksize;
 387
 388         /*
 389          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 390          * are reported in units of f_frsize.  Linux hasn't had
 391          * an f_frsize field in its statfs struct until recently,
 392          * thus historically Linux's sys_statfs reports these
 393          * fields in units of f_bsize.
 394          */
 395         buf->f_bsize = dentry->d_sb->s_blocksize;
 396         blockbits = dentry->d_sb->s_blocksize_bits;
 397         blockres = (1 << blockbits) - 1;
 398         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 399         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 400         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 401
 402         buf->f_files = res.tfiles;
 403         buf->f_ffree = res.afiles;
 404
 405         buf->f_namelen = server->namelen;
 406
 407         unlock_kernel();
 408         return 0;
 409
 410  out_err:
 411         dprintk("%s: statfs error = %d\n", __func__, -error);
 412         unlock_kernel();
 413         return error;
 414 }
 415
 416 /*
 417  * Map the security flavour number to a name
 418  */
 419 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 420 {
 421         static const struct {
 422                 rpc_authflavor_t flavour;
 423                 const char *str;
 424         } sec_flavours[] = {
 425                 { RPC_AUTH_NULL, "null" },
 426                 { RPC_AUTH_UNIX, "sys" },
 427                 { RPC_AUTH_GSS_KRB5, "krb5" },
 428                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 429                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 430                 { RPC_AUTH_GSS_LKEY, "lkey" },
 431                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 432                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 433                 { RPC_AUTH_GSS_SPKM, "spkm" },
 434                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 435                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 436                 { UINT_MAX, "unknown" }
 437         };
 438         int i;
 439
 440         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 441                 if (sec_flavours[i].flavour == flavour)
 442                         break;
 443         }
 444         return sec_flavours[i].str;
 445 }
 446
 447 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 448                                     int showdefaults)
 449 {
 450         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 451
 452         switch (sap->sa_family) {
 453         case AF_INET: {
 454                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 455                 seq_printf(m, ",mountaddr=" NIPQUAD_FMT,
 456                                 NIPQUAD(sin->sin_addr.s_addr));
 457                 break;
 458         }
 459         case AF_INET6: {
 460                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 461                 seq_printf(m, ",mountaddr=" NIP6_FMT,
 462                                 NIP6(sin6->sin6_addr));
 463                 break;
 464         }
 465         default:
 466                 if (showdefaults)
 467                         seq_printf(m, ",mountaddr=unspecified");
 468         }
 469
 470         if (nfss->mountd_version || showdefaults)
 471                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 472         if (nfss->mountd_port || showdefaults)
 473                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 474
 475         switch (nfss->mountd_protocol) {
 476         case IPPROTO_UDP:
 477                 seq_printf(m, ",mountproto=udp");
 478                 break;
 479         case IPPROTO_TCP:
 480                 seq_printf(m, ",mountproto=tcp");
 481                 break;
 482         default:
 483                 if (showdefaults)
 484                         seq_printf(m, ",mountproto=auto");
 485         }
 486 }
 487
 488 /*
 489  * Describe the mount options in force on this server representation
 490  */
 491 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 492                                    int showdefaults)
 493 {
 494         static const struct proc_nfs_info {
 495                 int flag;
 496                 const char *str;
 497                 const char *nostr;
 498         } nfs_info[] = {
 499                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 500                 { NFS_MOUNT_INTR, ",intr", ",nointr" },
 501                 { NFS_MOUNT_POSIX, ",posix", "" },
 502                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 503                 { NFS_MOUNT_NOAC, ",noac", "" },
 504                 { NFS_MOUNT_NONLM, ",nolock", "" },
 505                 { NFS_MOUNT_NOACL, ",noacl", "" },
 506                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 507                 { NFS_MOUNT_UNSHARED, ",nosharecache", ""},
 508                 { 0, NULL, NULL }
 509         };
 510         const struct proc_nfs_info *nfs_infop;
 511         struct nfs_client *clp = nfss->nfs_client;
 512         u32 version = clp->rpc_ops->version;
 513
 514         seq_printf(m, ",vers=%u", version);
 515         seq_printf(m, ",rsize=%u", nfss->rsize);
 516         seq_printf(m, ",wsize=%u", nfss->wsize);
 517         if (nfss->bsize != 0)
 518                 seq_printf(m, ",bsize=%u", nfss->bsize);
 519         seq_printf(m, ",namlen=%u", nfss->namelen);
 520         if (nfss->acregmin != 3*HZ || showdefaults)
 521                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 522         if (nfss->acregmax != 60*HZ || showdefaults)
 523                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 524         if (nfss->acdirmin != 30*HZ || showdefaults)
 525                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 526         if (nfss->acdirmax != 60*HZ || showdefaults)
 527                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 528         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 529                 if (nfss->flags & nfs_infop->flag)
 530                         seq_puts(m, nfs_infop->str);
 531                 else
 532                         seq_puts(m, nfs_infop->nostr);
 533         }
 534         seq_printf(m, ",proto=%s",
 535                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 536         if (version == 4) {
 537                 if (nfss->port != NFS_PORT)
 538                         seq_printf(m, ",port=%u", nfss->port);
 539         } else
 540                 if (nfss->port)
 541                         seq_printf(m, ",port=%u", nfss->port);
 542
 543         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 544         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 545         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 546
 547         if (version != 4)
 548                 nfs_show_mountd_options(m, nfss, showdefaults);
 549
 550 #ifdef CONFIG_NFS_V4
 551         if (clp->rpc_ops->version == 4)
 552                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 553 #endif
 554 }
 555
 556 /*
 557  * Describe the mount options on this VFS mountpoint
 558  */
 559 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 560 {
 561         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 562
 563         nfs_show_mount_options(m, nfss, 0);
 564
 565         seq_printf(m, ",addr=%s",
 566                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 567                                                         RPC_DISPLAY_ADDR));
 568
 569         return 0;
 570 }
 571
 572 /*
 573  * Present statistical information for this VFS mountpoint
 574  */
 575 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 576 {
 577         int i, cpu;
 578         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 579         struct rpc_auth *auth = nfss->client->cl_auth;
 580         struct nfs_iostats totals = { };
 581
 582         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 583
 584         /*
 585          * Display all mount option settings
 586          */
 587         seq_printf(m, "\n\topts:\t");
 588         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 589         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 590         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 591         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 592         nfs_show_mount_options(m, nfss, 1);
 593
 594         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 595
 596         seq_printf(m, "\n\tcaps:\t");
 597         seq_printf(m, "caps=0x%x", nfss->caps);
 598         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 599         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 600         seq_printf(m, ",bsize=%u", nfss->bsize);
 601         seq_printf(m, ",namlen=%u", nfss->namelen);
 602
 603 #ifdef CONFIG_NFS_V4
 604         if (nfss->nfs_client->rpc_ops->version == 4) {
 605                 seq_printf(m, "\n\tnfsv4:\t");
 606                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 607                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 608                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 609         }
 610 #endif
 611
 612         /*
 613          * Display security flavor in effect for this mount
 614          */
 615         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 616         if (auth->au_flavor)
 617                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 618
 619         /*
 620          * Display superblock I/O counters
 621          */
 622         for_each_possible_cpu(cpu) {
 623                 struct nfs_iostats *stats;
 624
 625                 preempt_disable();
 626                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 627
 628                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 629                         totals.events[i] += stats->events[i];
 630                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 631                         totals.bytes[i] += stats->bytes[i];
 632
 633                 preempt_enable();
 634         }
 635
 636         seq_printf(m, "\n\tevents:\t");
 637         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 638                 seq_printf(m, "%lu ", totals.events[i]);
 639         seq_printf(m, "\n\tbytes:\t");
 640         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 641                 seq_printf(m, "%Lu ", totals.bytes[i]);
 642         seq_printf(m, "\n");
 643
 644         rpc_print_iostats(m, nfss->client);
 645
 646         return 0;
 647 }
 648
 649 /*
 650  * Begin unmount by attempting to remove all automounted mountpoints we added
 651  * in response to xdev traversals and referrals
 652  */
 653 static void nfs_umount_begin(struct super_block *sb)
 654 {
 655         struct nfs_server *server = NFS_SB(sb);
 656         struct rpc_clnt *rpc;
 657
 658         /* -EIO all pending I/O */
 659         rpc = server->client_acl;
 660         if (!IS_ERR(rpc))
 661                 rpc_killall_tasks(rpc);
 662         rpc = server->client;
 663         if (!IS_ERR(rpc))
 664                 rpc_killall_tasks(rpc);
 665 }
 666
 667 /*
 668  * Set the port number in an address.  Be agnostic about the address family.
 669  */
 670 static void nfs_set_port(struct sockaddr *sap, unsigned short port)
 671 {
 672         switch (sap->sa_family) {
 673         case AF_INET: {
 674                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 675                 ap->sin_port = htons(port);
 676                 break;
 677         }
 678         case AF_INET6: {
 679                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 680                 ap->sin6_port = htons(port);
 681                 break;
 682         }
 683         }
 684 }
 685
 686 /*
 687  * Sanity-check a server address provided by the mount command.
 688  *
 689  * Address family must be initialized, and address must not be
 690  * the ANY address for that family.
 691  */
 692 static int nfs_verify_server_address(struct sockaddr *addr)
 693 {
 694         switch (addr->sa_family) {
 695         case AF_INET: {
 696                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 697                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 698         }
 699         case AF_INET6: {
 700                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 701                 return !ipv6_addr_any(sa);
 702         }
 703         }
 704
 705         return 0;
 706 }
 707
 708 /*
 709  * Parse string addresses passed in via a mount option,
 710  * and construct a sockaddr based on the result.
 711  *
 712  * If address parsing fails, set the sockaddr's address
 713  * family to AF_UNSPEC to force nfs_verify_server_address()
 714  * to punt the mount.
 715  */
 716 static void nfs_parse_server_address(char *value,
 717                                      struct sockaddr *sap,
 718                                      size_t *len)
 719 {
 720         if (strchr(value, ':')) {
 721                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 722                 u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
 723
 724                 ap->sin6_family = AF_INET6;
 725                 *len = sizeof(*ap);
 726                 if (in6_pton(value, -1, addr, '\0', NULL))
 727                         return;
 728         } else {
 729                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 730                 u8 *addr = (u8 *)&ap->sin_addr.s_addr;
 731
 732                 ap->sin_family = AF_INET;
 733                 *len = sizeof(*ap);
 734                 if (in4_pton(value, -1, addr, '\0', NULL))
 735                         return;
 736         }
 737
 738         sap->sa_family = AF_UNSPEC;
 739         *len = 0;
 740 }
 741
 742 /*
 743  * Error-check and convert a string of mount options from user space into
 744  * a data structure
 745  */
 746 static int nfs_parse_mount_options(char *raw,
 747                                    struct nfs_parsed_mount_data *mnt)
 748 {
 749         char *p, *string, *secdata;
 750         int rc;
 751
 752         if (!raw) {
 753                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 754                 return 1;
 755         }
 756         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 757
 758         secdata = alloc_secdata();
 759         if (!secdata)
 760                 goto out_nomem;
 761
 762         rc = security_sb_copy_data(raw, secdata);
 763         if (rc)
 764                 goto out_security_failure;
 765
 766         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 767         if (rc)
 768                 goto out_security_failure;
 769
 770         free_secdata(secdata);
 771
 772         while ((p = strsep(&raw, ",")) != NULL) {
 773                 substring_t args[MAX_OPT_ARGS];
 774                 int option, token;
 775
 776                 if (!*p)
 777                         continue;
 778
 779                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 780
 781                 token = match_token(p, nfs_mount_option_tokens, args);
 782                 switch (token) {
 783                 case Opt_soft:
 784                         mnt->flags |= NFS_MOUNT_SOFT;
 785                         break;
 786                 case Opt_hard:
 787                         mnt->flags &= ~NFS_MOUNT_SOFT;
 788                         break;
 789                 case Opt_posix:
 790                         mnt->flags |= NFS_MOUNT_POSIX;
 791                         break;
 792                 case Opt_noposix:
 793                         mnt->flags &= ~NFS_MOUNT_POSIX;
 794                         break;
 795                 case Opt_cto:
 796                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 797                         break;
 798                 case Opt_nocto:
 799                         mnt->flags |= NFS_MOUNT_NOCTO;
 800                         break;
 801                 case Opt_ac:
 802                         mnt->flags &= ~NFS_MOUNT_NOAC;
 803                         break;
 804                 case Opt_noac:
 805                         mnt->flags |= NFS_MOUNT_NOAC;
 806                         break;
 807                 case Opt_lock:
 808                         mnt->flags &= ~NFS_MOUNT_NONLM;
 809                         break;
 810                 case Opt_nolock:
 811                         mnt->flags |= NFS_MOUNT_NONLM;
 812                         break;
 813                 case Opt_v2:
 814                         mnt->flags &= ~NFS_MOUNT_VER3;
 815                         break;
 816                 case Opt_v3:
 817                         mnt->flags |= NFS_MOUNT_VER3;
 818                         break;
 819                 case Opt_udp:
 820                         mnt->flags &= ~NFS_MOUNT_TCP;
 821                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 822                         mnt->timeo = 7;
 823                         mnt->retrans = 5;
 824                         break;
 825                 case Opt_tcp:
 826                         mnt->flags |= NFS_MOUNT_TCP;
 827                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 828                         mnt->timeo = 600;
 829                         mnt->retrans = 2;
 830                         break;
 831                 case Opt_rdma:
 832                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 833                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 834                         mnt->timeo = 600;
 835                         mnt->retrans = 2;
 836                         break;
 837                 case Opt_acl:
 838                         mnt->flags &= ~NFS_MOUNT_NOACL;
 839                         break;
 840                 case Opt_noacl:
 841                         mnt->flags |= NFS_MOUNT_NOACL;
 842                         break;
 843                 case Opt_rdirplus:
 844                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 845                         break;
 846                 case Opt_nordirplus:
 847                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 848                         break;
 849                 case Opt_sharecache:
 850                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 851                         break;
 852                 case Opt_nosharecache:
 853                         mnt->flags |= NFS_MOUNT_UNSHARED;
 854                         break;
 855
 856                 case Opt_port:
 857                         if (match_int(args, &option))
 858                                 return 0;
 859                         if (option < 0 || option > 65535)
 860                                 return 0;
 861                         mnt->nfs_server.port = option;
 862                         break;
 863                 case Opt_rsize:
 864                         if (match_int(args, &mnt->rsize))
 865                                 return 0;
 866                         break;
 867                 case Opt_wsize:
 868                         if (match_int(args, &mnt->wsize))
 869                                 return 0;
 870                         break;
 871                 case Opt_bsize:
 872                         if (match_int(args, &option))
 873                                 return 0;
 874                         if (option < 0)
 875                                 return 0;
 876                         mnt->bsize = option;
 877                         break;
 878                 case Opt_timeo:
 879                         if (match_int(args, &mnt->timeo))
 880                                 return 0;
 881                         break;
 882                 case Opt_retrans:
 883                         if (match_int(args, &mnt->retrans))
 884                                 return 0;
 885                         break;
 886                 case Opt_acregmin:
 887                         if (match_int(args, &mnt->acregmin))
 888                                 return 0;
 889                         break;
 890                 case Opt_acregmax:
 891                         if (match_int(args, &mnt->acregmax))
 892                                 return 0;
 893                         break;
 894                 case Opt_acdirmin:
 895                         if (match_int(args, &mnt->acdirmin))
 896                                 return 0;
 897                         break;
 898                 case Opt_acdirmax:
 899                         if (match_int(args, &mnt->acdirmax))
 900                                 return 0;
 901                         break;
 902                 case Opt_actimeo:
 903                         if (match_int(args, &option))
 904                                 return 0;
 905                         if (option < 0)
 906                                 return 0;
 907                         mnt->acregmin =
 908                         mnt->acregmax =
 909                         mnt->acdirmin =
 910                         mnt->acdirmax = option;
 911                         break;
 912                 case Opt_namelen:
 913                         if (match_int(args, &mnt->namlen))
 914                                 return 0;
 915                         break;
 916                 case Opt_mountport:
 917                         if (match_int(args, &option))
 918                                 return 0;
 919                         if (option < 0 || option > 65535)
 920                                 return 0;
 921                         mnt->mount_server.port = option;
 922                         break;
 923                 case Opt_mountvers:
 924                         if (match_int(args, &option))
 925                                 return 0;
 926                         if (option < 0)
 927                                 return 0;
 928                         mnt->mount_server.version = option;
 929                         break;
 930                 case Opt_nfsvers:
 931                         if (match_int(args, &option))
 932                                 return 0;
 933                         switch (option) {
 934                         case 2:
 935                                 mnt->flags &= ~NFS_MOUNT_VER3;
 936                                 break;
 937                         case 3:
 938                                 mnt->flags |= NFS_MOUNT_VER3;
 939                                 break;
 940                         default:
 941                                 goto out_unrec_vers;
 942                         }
 943                         break;
 944
 945                 case Opt_sec:
 946                         string = match_strdup(args);
 947                         if (string == NULL)
 948                                 goto out_nomem;
 949                         token = match_token(string, nfs_secflavor_tokens, args);
 950                         kfree(string);
 951
 952                         /*
 953                          * The flags setting is for v2/v3.  The flavor_len
 954                          * setting is for v4.  v2/v3 also need to know the
 955                          * difference between NULL and UNIX.
 956                          */
 957                         switch (token) {
 958                         case Opt_sec_none:
 959                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 960                                 mnt->auth_flavor_len = 0;
 961                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 962                                 break;
 963                         case Opt_sec_sys:
 964                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 965                                 mnt->auth_flavor_len = 0;
 966                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 967                                 break;
 968                         case Opt_sec_krb5:
 969                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 970                                 mnt->auth_flavor_len = 1;
 971                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 972                                 break;
 973                         case Opt_sec_krb5i:
 974                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 975                                 mnt->auth_flavor_len = 1;
 976                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 977                                 break;
 978                         case Opt_sec_krb5p:
 979                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 980                                 mnt->auth_flavor_len = 1;
 981                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 982                                 break;
 983                         case Opt_sec_lkey:
 984                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 985                                 mnt->auth_flavor_len = 1;
 986                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 987                                 break;
 988                         case Opt_sec_lkeyi:
 989                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 990                                 mnt->auth_flavor_len = 1;
 991                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 992                                 break;
 993                         case Opt_sec_lkeyp:
 994                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 995                                 mnt->auth_flavor_len = 1;
 996                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 997                                 break;
 998                         case Opt_sec_spkm:
 999                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1000                                 mnt->auth_flavor_len = 1;
1001                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1002                                 break;
1003                         case Opt_sec_spkmi:
1004                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1005                                 mnt->auth_flavor_len = 1;
1006                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1007                                 break;
1008                         case Opt_sec_spkmp:
1009                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1010                                 mnt->auth_flavor_len = 1;
1011                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1012                                 break;
1013                         default:
1014                                 goto out_unrec_sec;
1015                         }
1016                         break;
1017                 case Opt_proto:
1018                         string = match_strdup(args);
1019                         if (string == NULL)
1020                                 goto out_nomem;
1021                         token = match_token(string,
1022                                             nfs_xprt_protocol_tokens, args);
1023                         kfree(string);
1024
1025                         switch (token) {
1026                         case Opt_xprt_udp:
1027                                 mnt->flags &= ~NFS_MOUNT_TCP;
1028                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1029                                 mnt->timeo = 7;
1030                                 mnt->retrans = 5;
1031                                 break;
1032                         case Opt_xprt_tcp:
1033                                 mnt->flags |= NFS_MOUNT_TCP;
1034                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1035                                 mnt->timeo = 600;
1036                                 mnt->retrans = 2;
1037                                 break;
1038                         case Opt_xprt_rdma:
1039                                 /* vector side protocols to TCP */
1040                                 mnt->flags |= NFS_MOUNT_TCP;
1041                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1042                                 mnt->timeo = 600;
1043                                 mnt->retrans = 2;
1044                                 break;
1045                         default:
1046                                 goto out_unrec_xprt;
1047                         }
1048                         break;
1049                 case Opt_mountproto:
1050                         string = match_strdup(args);
1051                         if (string == NULL)
1052                                 goto out_nomem;
1053                         token = match_token(string,
1054                                             nfs_xprt_protocol_tokens, args);
1055                         kfree(string);
1056
1057                         switch (token) {
1058                         case Opt_xprt_udp:
1059                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1060                                 break;
1061                         case Opt_xprt_tcp:
1062                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1063                                 break;
1064                         case Opt_xprt_rdma: /* not used for side protocols */
1065                         default:
1066                                 goto out_unrec_xprt;
1067                         }
1068                         break;
1069                 case Opt_addr:
1070                         string = match_strdup(args);
1071                         if (string == NULL)
1072                                 goto out_nomem;
1073                         nfs_parse_server_address(string, (struct sockaddr *)
1074                                                  &mnt->nfs_server.address,
1075                                                  &mnt->nfs_server.addrlen);
1076                         kfree(string);
1077                         break;
1078                 case Opt_clientaddr:
1079                         string = match_strdup(args);
1080                         if (string == NULL)
1081                                 goto out_nomem;
1082                         kfree(mnt->client_address);
1083                         mnt->client_address = string;
1084                         break;
1085                 case Opt_mounthost:
1086                         string = match_strdup(args);
1087                         if (string == NULL)
1088                                 goto out_nomem;
1089                         kfree(mnt->mount_server.hostname);
1090                         mnt->mount_server.hostname = string;
1091                         break;
1092                 case Opt_mountaddr:
1093                         string = match_strdup(args);
1094                         if (string == NULL)
1095                                 goto out_nomem;
1096                         nfs_parse_server_address(string, (struct sockaddr *)
1097                                                  &mnt->mount_server.address,
1098                                                  &mnt->mount_server.addrlen);
1099                         kfree(string);
1100                         break;
1101
1102                 case Opt_userspace:
1103                 case Opt_deprecated:
1104                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1105                                         "'%s'\n", p);
1106                         break;
1107
1108                 default:
1109                         goto out_unknown;
1110                 }
1111         }
1112
1113         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
1114                                 mnt->nfs_server.port);
1115
1116         return 1;
1117
1118 out_nomem:
1119         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1120         return 0;
1121 out_security_failure:
1122         free_secdata(secdata);
1123         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1124         return 0;
1125 out_unrec_vers:
1126         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1127         return 0;
1128
1129 out_unrec_xprt:
1130         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1131         return 0;
1132
1133 out_unrec_sec:
1134         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1135         return 0;
1136
1137 out_unknown:
1138         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1139         return 0;
1140 }
1141
1142 /*
1143  * Use the remote server's MOUNT service to request the NFS file handle
1144  * corresponding to the provided path.
1145  */
1146 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1147                          struct nfs_fh *root_fh)
1148 {
1149         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1150         char *hostname;
1151         int status;
1152
1153         if (args->mount_server.version == 0) {
1154                 if (args->flags & NFS_MOUNT_VER3)
1155                         args->mount_server.version = NFS_MNT3_VERSION;
1156                 else
1157                         args->mount_server.version = NFS_MNT_VERSION;
1158         }
1159
1160         if (args->mount_server.hostname)
1161                 hostname = args->mount_server.hostname;
1162         else
1163                 hostname = args->nfs_server.hostname;
1164
1165         /*
1166          * Construct the mount server's address.
1167          */
1168         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1169                 memcpy(sap, &args->nfs_server.address,
1170                        args->nfs_server.addrlen);
1171                 args->mount_server.addrlen = args->nfs_server.addrlen;
1172         }
1173
1174         /*
1175          * autobind will be used if mount_server.port == 0
1176          */
1177         nfs_set_port(sap, args->mount_server.port);
1178
1179         /*
1180          * Now ask the mount server to map our export path
1181          * to a file handle.
1182          */
1183         status = nfs_mount(sap,
1184                            args->mount_server.addrlen,
1185                            hostname,
1186                            args->nfs_server.export_path,
1187                            args->mount_server.version,
1188                            args->mount_server.protocol,
1189                            root_fh);
1190         if (status == 0)
1191                 return 0;
1192
1193         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1194                         hostname, status);
1195         return status;
1196 }
1197
1198 static int nfs_parse_simple_hostname(const char *dev_name,
1199                                      char **hostname, size_t maxnamlen,
1200                                      char **export_path, size_t maxpathlen)
1201 {
1202         size_t len;
1203         char *colon, *comma;
1204
1205         colon = strchr(dev_name, ':');
1206         if (colon == NULL)
1207                 goto out_bad_devname;
1208
1209         len = colon - dev_name;
1210         if (len > maxnamlen)
1211                 goto out_hostname;
1212
1213         /* N.B. caller will free nfs_server.hostname in all cases */
1214         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1215         if (!*hostname)
1216                 goto out_nomem;
1217
1218         /* kill possible hostname list: not supported */
1219         comma = strchr(*hostname, ',');
1220         if (comma != NULL) {
1221                 if (comma == *hostname)
1222                         goto out_bad_devname;
1223                 *comma = '\0';
1224         }
1225
1226         colon++;
1227         len = strlen(colon);
1228         if (len > maxpathlen)
1229                 goto out_path;
1230         *export_path = kstrndup(colon, len, GFP_KERNEL);
1231         if (!*export_path)
1232                 goto out_nomem;
1233
1234         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1235         return 0;
1236
1237 out_bad_devname:
1238         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1239         return -EINVAL;
1240
1241 out_nomem:
1242         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1243         return -ENOMEM;
1244
1245 out_hostname:
1246         dfprintk(MOUNT, "NFS: server hostname too long\n");
1247         return -ENAMETOOLONG;
1248
1249 out_path:
1250         dfprintk(MOUNT, "NFS: export pathname too long\n");
1251         return -ENAMETOOLONG;
1252 }
1253
1254 /*
1255  * Hostname has square brackets around it because it contains one or
1256  * more colons.  We look for the first closing square bracket, and a
1257  * colon must follow it.
1258  */
1259 static int nfs_parse_protected_hostname(const char *dev_name,
1260                                         char **hostname, size_t maxnamlen,
1261                                         char **export_path, size_t maxpathlen)
1262 {
1263         size_t len;
1264         char *start, *end;
1265
1266         start = (char *)(dev_name + 1);
1267
1268         end = strchr(start, ']');
1269         if (end == NULL)
1270                 goto out_bad_devname;
1271         if (*(end + 1) != ':')
1272                 goto out_bad_devname;
1273
1274         len = end - start;
1275         if (len > maxnamlen)
1276                 goto out_hostname;
1277
1278         /* N.B. caller will free nfs_server.hostname in all cases */
1279         *hostname = kstrndup(start, len, GFP_KERNEL);
1280         if (*hostname == NULL)
1281                 goto out_nomem;
1282
1283         end += 2;
1284         len = strlen(end);
1285         if (len > maxpathlen)
1286                 goto out_path;
1287         *export_path = kstrndup(end, len, GFP_KERNEL);
1288         if (!*export_path)
1289                 goto out_nomem;
1290
1291         return 0;
1292
1293 out_bad_devname:
1294         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1295         return -EINVAL;
1296
1297 out_nomem:
1298         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1299         return -ENOMEM;
1300
1301 out_hostname:
1302         dfprintk(MOUNT, "NFS: server hostname too long\n");
1303         return -ENAMETOOLONG;
1304
1305 out_path:
1306         dfprintk(MOUNT, "NFS: export pathname too long\n");
1307         return -ENAMETOOLONG;
1308 }
1309
1310 /*
1311  * Split "dev_name" into "hostname:export_path".
1312  *
1313  * The leftmost colon demarks the split between the server's hostname
1314  * and the export path.  If the hostname starts with a left square
1315  * bracket, then it may contain colons.
1316  *
1317  * Note: caller frees hostname and export path, even on error.
1318  */
1319 static int nfs_parse_devname(const char *dev_name,
1320                              char **hostname, size_t maxnamlen,
1321                              char **export_path, size_t maxpathlen)
1322 {
1323         if (*dev_name == '[')
1324                 return nfs_parse_protected_hostname(dev_name,
1325                                                     hostname, maxnamlen,
1326                                                     export_path, maxpathlen);
1327
1328         return nfs_parse_simple_hostname(dev_name,
1329                                          hostname, maxnamlen,
1330                                          export_path, maxpathlen);
1331 }
1332
1333 /*
1334  * Validate the NFS2/NFS3 mount data
1335  * - fills in the mount root filehandle
1336  *
1337  * For option strings, user space handles the following behaviors:
1338  *
1339  * + DNS: mapping server host name to IP address ("addr=" option)
1340  *
1341  * + failure mode: how to behave if a mount request can't be handled
1342  *   immediately ("fg/bg" option)
1343  *
1344  * + retry: how often to retry a mount request ("retry=" option)
1345  *
1346  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1347  *   mountproto=tcp after mountproto=udp, and so on
1348  */
1349 static int nfs_validate_mount_data(void *options,
1350                                    struct nfs_parsed_mount_data *args,
1351                                    struct nfs_fh *mntfh,
1352                                    const char *dev_name)
1353 {
1354         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1355
1356         if (data == NULL)
1357                 goto out_no_data;
1358
1359         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1360         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1361         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1362         args->timeo             = 600;
1363         args->retrans           = 2;
1364         args->acregmin          = 3;
1365         args->acregmax          = 60;
1366         args->acdirmin          = 30;
1367         args->acdirmax          = 60;
1368         args->mount_server.port = 0;    /* autobind unless user sets port */
1369         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1370         args->nfs_server.port   = 0;    /* autobind unless user sets port */
1371         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1372
1373         switch (data->version) {
1374         case 1:
1375                 data->namlen = 0;
1376         case 2:
1377                 data->bsize = 0;
1378         case 3:
1379                 if (data->flags & NFS_MOUNT_VER3)
1380                         goto out_no_v3;
1381                 data->root.size = NFS2_FHSIZE;
1382                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1383         case 4:
1384                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1385                         goto out_no_sec;
1386         case 5:
1387                 memset(data->context, 0, sizeof(data->context));
1388         case 6:
1389                 if (data->flags & NFS_MOUNT_VER3) {
1390                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1391                                 goto out_invalid_fh;
1392                         mntfh->size = data->root.size;
1393                 } else
1394                         mntfh->size = NFS2_FHSIZE;
1395
1396
1397                 memcpy(mntfh->data, data->root.data, mntfh->size);
1398                 if (mntfh->size < sizeof(mntfh->data))
1399                         memset(mntfh->data + mntfh->size, 0,
1400                                sizeof(mntfh->data) - mntfh->size);
1401
1402                 /*
1403                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1404                  * can deal with.
1405                  */
1406                 args->flags             = data->flags;
1407                 args->rsize             = data->rsize;
1408                 args->wsize             = data->wsize;
1409                 args->timeo             = data->timeo;
1410                 args->retrans           = data->retrans;
1411                 args->acregmin          = data->acregmin;
1412                 args->acregmax          = data->acregmax;
1413                 args->acdirmin          = data->acdirmin;
1414                 args->acdirmax          = data->acdirmax;
1415
1416                 memcpy(&args->nfs_server.address, &data->addr,
1417                        sizeof(data->addr));
1418                 args->nfs_server.addrlen = sizeof(data->addr);
1419                 if (!nfs_verify_server_address((struct sockaddr *)
1420                                                 &args->nfs_server.address))
1421                         goto out_no_address;
1422
1423                 if (!(data->flags & NFS_MOUNT_TCP))
1424                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1425                 /* N.B. caller will free nfs_server.hostname in all cases */
1426                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1427                 args->namlen            = data->namlen;
1428                 args->bsize             = data->bsize;
1429                 args->auth_flavors[0]   = data->pseudoflavor;
1430                 if (!args->nfs_server.hostname)
1431                         goto out_nomem;
1432
1433                 /*
1434                  * The legacy version 6 binary mount data from userspace has a
1435                  * field used only to transport selinux information into the
1436                  * the kernel.  To continue to support that functionality we
1437                  * have a touch of selinux knowledge here in the NFS code. The
1438                  * userspace code converted context=blah to just blah so we are
1439                  * converting back to the full string selinux understands.
1440                  */
1441                 if (data->context[0]){
1442 #ifdef CONFIG_SECURITY_SELINUX
1443                         int rc;
1444                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1445                         if (!opts_str)
1446                                 return -ENOMEM;
1447                         strcpy(opts_str, "context=");
1448                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1449                         strcat(opts_str, &data->context[0]);
1450                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1451                         kfree(opts_str);
1452                         if (rc)
1453                                 return rc;
1454 #else
1455                         return -EINVAL;
1456 #endif
1457                 }
1458
1459                 break;
1460         default: {
1461                 int status;
1462
1463                 if (nfs_parse_mount_options((char *)options, args) == 0)
1464                         return -EINVAL;
1465
1466                 if (!nfs_verify_server_address((struct sockaddr *)
1467                                                 &args->nfs_server.address))
1468                         goto out_no_address;
1469
1470                 status = nfs_parse_devname(dev_name,
1471                                            &args->nfs_server.hostname,
1472                                            PAGE_SIZE,
1473                                            &args->nfs_server.export_path,
1474                                            NFS_MAXPATHLEN);
1475                 if (!status)
1476                         status = nfs_try_mount(args, mntfh);
1477
1478                 kfree(args->nfs_server.export_path);
1479                 args->nfs_server.export_path = NULL;
1480
1481                 if (status)
1482                         return status;
1483
1484                 break;
1485                 }
1486         }
1487
1488         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1489                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1490
1491 #ifndef CONFIG_NFS_V3
1492         if (args->flags & NFS_MOUNT_VER3)
1493                 goto out_v3_not_compiled;
1494 #endif /* !CONFIG_NFS_V3 */
1495
1496         return 0;
1497
1498 out_no_data:
1499         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1500         return -EINVAL;
1501
1502 out_no_v3:
1503         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1504                  data->version);
1505         return -EINVAL;
1506
1507 out_no_sec:
1508         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1509         return -EINVAL;
1510
1511 #ifndef CONFIG_NFS_V3
1512 out_v3_not_compiled:
1513         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1514         return -EPROTONOSUPPORT;
1515 #endif /* !CONFIG_NFS_V3 */
1516
1517 out_nomem:
1518         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1519         return -ENOMEM;
1520
1521 out_no_address:
1522         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1523         return -EINVAL;
1524
1525 out_invalid_fh:
1526         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1527         return -EINVAL;
1528 }
1529
1530 static int
1531 nfs_compare_remount_data(struct nfs_server *nfss,
1532                          struct nfs_parsed_mount_data *data)
1533 {
1534         if (data->flags != nfss->flags ||
1535             data->rsize != nfss->rsize ||
1536             data->wsize != nfss->wsize ||
1537             data->retrans != nfss->client->cl_timeout->to_retries ||
1538             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1539             data->acregmin != nfss->acregmin / HZ ||
1540             data->acregmax != nfss->acregmax / HZ ||
1541             data->acdirmin != nfss->acdirmin / HZ ||
1542             data->acdirmax != nfss->acdirmax / HZ ||
1543             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1544             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1545             memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1546                    data->nfs_server.addrlen) != 0)
1547                 return -EINVAL;
1548
1549         return 0;
1550 }
1551
1552 static int
1553 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1554 {
1555         int error;
1556         struct nfs_server *nfss = sb->s_fs_info;
1557         struct nfs_parsed_mount_data *data;
1558         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1559         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1560         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1561
1562         /*
1563          * Userspace mount programs that send binary options generally send
1564          * them populated with default values. We have no way to know which
1565          * ones were explicitly specified. Fall back to legacy behavior and
1566          * just return success.
1567          */
1568         if ((nfsvers == 4 && options4->version == 1) ||
1569             (nfsvers <= 3 && options->version >= 1 &&
1570              options->version <= 6))
1571                 return 0;
1572
1573         data = kzalloc(sizeof(*data), GFP_KERNEL);
1574         if (data == NULL)
1575                 return -ENOMEM;
1576
1577         /* fill out struct with values from existing mount */
1578         data->flags = nfss->flags;
1579         data->rsize = nfss->rsize;
1580         data->wsize = nfss->wsize;
1581         data->retrans = nfss->client->cl_timeout->to_retries;
1582         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1583         data->acregmin = nfss->acregmin / HZ;
1584         data->acregmax = nfss->acregmax / HZ;
1585         data->acdirmin = nfss->acdirmin / HZ;
1586         data->acdirmax = nfss->acdirmax / HZ;
1587         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1588         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1589         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1590                 data->nfs_server.addrlen);
1591
1592         /* overwrite those values with any that were specified */
1593         error = nfs_parse_mount_options((char *)options, data);
1594         if (error < 0)
1595                 goto out;
1596
1597         /* compare new mount options with old ones */
1598         error = nfs_compare_remount_data(nfss, data);
1599 out:
1600         kfree(data);
1601         return error;
1602 }
1603
1604 /*
1605  * Initialise the common bits of the superblock
1606  */
1607 static inline void nfs_initialise_sb(struct super_block *sb)
1608 {
1609         struct nfs_server *server = NFS_SB(sb);
1610
1611         sb->s_magic = NFS_SUPER_MAGIC;
1612
1613         /* We probably want something more informative here */
1614         snprintf(sb->s_id, sizeof(sb->s_id),
1615                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1616
1617         if (sb->s_blocksize == 0)
1618                 sb->s_blocksize = nfs_block_bits(server->wsize,
1619                                                  &sb->s_blocksize_bits);
1620
1621         if (server->flags & NFS_MOUNT_NOAC)
1622                 sb->s_flags |= MS_SYNCHRONOUS;
1623
1624         nfs_super_set_maxbytes(sb, server->maxfilesize);
1625 }
1626
1627 /*
1628  * Finish setting up an NFS2/3 superblock
1629  */
1630 static void nfs_fill_super(struct super_block *sb,
1631                            struct nfs_parsed_mount_data *data)
1632 {
1633         struct nfs_server *server = NFS_SB(sb);
1634
1635         sb->s_blocksize_bits = 0;
1636         sb->s_blocksize = 0;
1637         if (data->bsize)
1638                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1639
1640         if (server->flags & NFS_MOUNT_VER3) {
1641                 /* The VFS shouldn't apply the umask to mode bits. We will do
1642                  * so ourselves when necessary.
1643                  */
1644                 sb->s_flags |= MS_POSIXACL;
1645                 sb->s_time_gran = 1;
1646         }
1647
1648         sb->s_op = &nfs_sops;
1649         nfs_initialise_sb(sb);
1650 }
1651
1652 /*
1653  * Finish setting up a cloned NFS2/3 superblock
1654  */
1655 static void nfs_clone_super(struct super_block *sb,
1656                             const struct super_block *old_sb)
1657 {
1658         struct nfs_server *server = NFS_SB(sb);
1659
1660         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1661         sb->s_blocksize = old_sb->s_blocksize;
1662         sb->s_maxbytes = old_sb->s_maxbytes;
1663
1664         if (server->flags & NFS_MOUNT_VER3) {
1665                 /* The VFS shouldn't apply the umask to mode bits. We will do
1666                  * so ourselves when necessary.
1667                  */
1668                 sb->s_flags |= MS_POSIXACL;
1669                 sb->s_time_gran = 1;
1670         }
1671
1672         sb->s_op = old_sb->s_op;
1673         nfs_initialise_sb(sb);
1674 }
1675
1676 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1677
1678 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1679 {
1680         const struct nfs_server *a = s->s_fs_info;
1681         const struct rpc_clnt *clnt_a = a->client;
1682         const struct rpc_clnt *clnt_b = b->client;
1683
1684         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1685                 goto Ebusy;
1686         if (a->nfs_client != b->nfs_client)
1687                 goto Ebusy;
1688         if (a->flags != b->flags)
1689                 goto Ebusy;
1690         if (a->wsize != b->wsize)
1691                 goto Ebusy;
1692         if (a->rsize != b->rsize)
1693                 goto Ebusy;
1694         if (a->acregmin != b->acregmin)
1695                 goto Ebusy;
1696         if (a->acregmax != b->acregmax)
1697                 goto Ebusy;
1698         if (a->acdirmin != b->acdirmin)
1699                 goto Ebusy;
1700         if (a->acdirmax != b->acdirmax)
1701                 goto Ebusy;
1702         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1703                 goto Ebusy;
1704         return 1;
1705 Ebusy:
1706         return 0;
1707 }
1708
1709 struct nfs_sb_mountdata {
1710         struct nfs_server *server;
1711         int mntflags;
1712 };
1713
1714 static int nfs_set_super(struct super_block *s, void *data)
1715 {
1716         struct nfs_sb_mountdata *sb_mntdata = data;
1717         struct nfs_server *server = sb_mntdata->server;
1718         int ret;
1719
1720         s->s_flags = sb_mntdata->mntflags;
1721         s->s_fs_info = server;
1722         ret = set_anon_super(s, server);
1723         if (ret == 0)
1724                 server->s_dev = s->s_dev;
1725         return ret;
1726 }
1727
1728 static int nfs_compare_super_address(struct nfs_server *server1,
1729                                      struct nfs_server *server2)
1730 {
1731         struct sockaddr *sap1, *sap2;
1732
1733         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1734         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1735
1736         if (sap1->sa_family != sap2->sa_family)
1737                 return 0;
1738
1739         switch (sap1->sa_family) {
1740         case AF_INET: {
1741                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1742                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1743                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1744                         return 0;
1745                 if (sin1->sin_port != sin2->sin_port)
1746                         return 0;
1747                 break;
1748         }
1749         case AF_INET6: {
1750                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1751                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1752                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1753                         return 0;
1754                 if (sin1->sin6_port != sin2->sin6_port)
1755                         return 0;
1756                 break;
1757         }
1758         default:
1759                 return 0;
1760         }
1761
1762         return 1;
1763 }
1764
1765 static int nfs_compare_super(struct super_block *sb, void *data)
1766 {
1767         struct nfs_sb_mountdata *sb_mntdata = data;
1768         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1769         int mntflags = sb_mntdata->mntflags;
1770
1771         if (!nfs_compare_super_address(old, server))
1772                 return 0;
1773         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1774         if (old->flags & NFS_MOUNT_UNSHARED)
1775                 return 0;
1776         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1777                 return 0;
1778         return nfs_compare_mount_options(sb, server, mntflags);
1779 }
1780
1781 static int nfs_bdi_register(struct nfs_server *server)
1782 {
1783         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
1784 }
1785
1786 static int nfs_get_sb(struct file_system_type *fs_type,
1787         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1788 {
1789         struct nfs_server *server = NULL;
1790         struct super_block *s;
1791         struct nfs_parsed_mount_data *data;
1792         struct nfs_fh *mntfh;
1793         struct dentry *mntroot;
1794         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1795         struct nfs_sb_mountdata sb_mntdata = {
1796                 .mntflags = flags,
1797         };
1798         int error = -ENOMEM;
1799
1800         data = kzalloc(sizeof(*data), GFP_KERNEL);
1801         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
1802         if (data == NULL || mntfh == NULL)
1803                 goto out_free_fh;
1804
1805         security_init_mnt_opts(&data->lsm_opts);
1806
1807         /* Validate the mount data */
1808         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
1809         if (error < 0)
1810                 goto out;
1811
1812         /* Get a volume representation */
1813         server = nfs_create_server(data, mntfh);
1814         if (IS_ERR(server)) {
1815                 error = PTR_ERR(server);
1816                 goto out;
1817         }
1818         sb_mntdata.server = server;
1819
1820         if (server->flags & NFS_MOUNT_UNSHARED)
1821                 compare_super = NULL;
1822
1823         /* Get a superblock - note that we may end up sharing one that already exists */
1824         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1825         if (IS_ERR(s)) {
1826                 error = PTR_ERR(s);
1827                 goto out_err_nosb;
1828         }
1829
1830         if (s->s_fs_info != server) {
1831                 nfs_free_server(server);
1832                 server = NULL;
1833         } else {
1834                 error = nfs_bdi_register(server);
1835                 if (error)
1836                         goto error_splat_super;
1837         }
1838
1839         if (!s->s_root) {
1840                 /* initial superblock/root creation */
1841                 nfs_fill_super(s, data);
1842         }
1843
1844         mntroot = nfs_get_root(s, mntfh);
1845         if (IS_ERR(mntroot)) {
1846                 error = PTR_ERR(mntroot);
1847                 goto error_splat_super;
1848         }
1849
1850         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
1851         if (error)
1852                 goto error_splat_root;
1853
1854         s->s_flags |= MS_ACTIVE;
1855         mnt->mnt_sb = s;
1856         mnt->mnt_root = mntroot;
1857         error = 0;
1858
1859 out:
1860         kfree(data->nfs_server.hostname);
1861         kfree(data->mount_server.hostname);
1862         security_free_mnt_opts(&data->lsm_opts);
1863 out_free_fh:
1864         kfree(mntfh);
1865         kfree(data);
1866         return error;
1867
1868 out_err_nosb:
1869         nfs_free_server(server);
1870         goto out;
1871
1872 error_splat_root:
1873         dput(mntroot);
1874 error_splat_super:
1875         up_write(&s->s_umount);
1876         deactivate_super(s);
1877         goto out;
1878 }
1879
1880 /*
1881  * Destroy an NFS2/3 superblock
1882  */
1883 static void nfs_kill_super(struct super_block *s)
1884 {
1885         struct nfs_server *server = NFS_SB(s);
1886
1887         bdi_unregister(&server->backing_dev_info);
1888         kill_anon_super(s);
1889         nfs_free_server(server);
1890 }
1891
1892 /*
1893  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1894  */
1895 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1896                            const char *dev_name, void *raw_data,
1897                            struct vfsmount *mnt)
1898 {
1899         struct nfs_clone_mount *data = raw_data;
1900         struct super_block *s;
1901         struct nfs_server *server;
1902         struct dentry *mntroot;
1903         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1904         struct nfs_sb_mountdata sb_mntdata = {
1905                 .mntflags = flags,
1906         };
1907         int error;
1908
1909         dprintk("--> nfs_xdev_get_sb()\n");
1910
1911         /* create a new volume representation */
1912         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1913         if (IS_ERR(server)) {
1914                 error = PTR_ERR(server);
1915                 goto out_err_noserver;
1916         }
1917         sb_mntdata.server = server;
1918
1919         if (server->flags & NFS_MOUNT_UNSHARED)
1920                 compare_super = NULL;
1921
1922         /* Get a superblock - note that we may end up sharing one that already exists */
1923         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1924         if (IS_ERR(s)) {
1925                 error = PTR_ERR(s);
1926                 goto out_err_nosb;
1927         }
1928
1929         if (s->s_fs_info != server) {
1930                 nfs_free_server(server);
1931                 server = NULL;
1932         } else {
1933                 error = nfs_bdi_register(server);
1934                 if (error)
1935                         goto error_splat_super;
1936         }
1937
1938         if (!s->s_root) {
1939                 /* initial superblock/root creation */
1940                 nfs_clone_super(s, data->sb);
1941         }
1942
1943         mntroot = nfs_get_root(s, data->fh);
1944         if (IS_ERR(mntroot)) {
1945                 error = PTR_ERR(mntroot);
1946                 goto error_splat_super;
1947         }
1948         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1949                 dput(mntroot);
1950                 error = -ESTALE;
1951                 goto error_splat_super;
1952         }
1953
1954         s->s_flags |= MS_ACTIVE;
1955         mnt->mnt_sb = s;
1956         mnt->mnt_root = mntroot;
1957
1958         /* clone any lsm security options from the parent to the new sb */
1959         security_sb_clone_mnt_opts(data->sb, s);
1960
1961         dprintk("<-- nfs_xdev_get_sb() = 0\n");
1962         return 0;
1963
1964 out_err_nosb:
1965         nfs_free_server(server);
1966 out_err_noserver:
1967         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
1968         return error;
1969
1970 error_splat_super:
1971         up_write(&s->s_umount);
1972         deactivate_super(s);
1973         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
1974         return error;
1975 }
1976
1977 #ifdef CONFIG_NFS_V4
1978
1979 /*
1980  * Finish setting up a cloned NFS4 superblock
1981  */
1982 static void nfs4_clone_super(struct super_block *sb,
1983                             const struct super_block *old_sb)
1984 {
1985         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1986         sb->s_blocksize = old_sb->s_blocksize;
1987         sb->s_maxbytes = old_sb->s_maxbytes;
1988         sb->s_time_gran = 1;
1989         sb->s_op = old_sb->s_op;
1990         nfs_initialise_sb(sb);
1991 }
1992
1993 /*
1994  * Set up an NFS4 superblock
1995  */
1996 static void nfs4_fill_super(struct super_block *sb)
1997 {
1998         sb->s_time_gran = 1;
1999         sb->s_op = &nfs4_sops;
2000         nfs_initialise_sb(sb);
2001 }
2002
2003 /*
2004  * Validate NFSv4 mount options
2005  */
2006 static int nfs4_validate_mount_data(void *options,
2007                                     struct nfs_parsed_mount_data *args,
2008                                     const char *dev_name)
2009 {
2010         struct sockaddr_in *ap;
2011         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2012         char *c;
2013
2014         if (data == NULL)
2015                 goto out_no_data;
2016
2017         args->rsize             = NFS_MAX_FILE_IO_SIZE;
2018         args->wsize             = NFS_MAX_FILE_IO_SIZE;
2019         args->timeo             = 600;
2020         args->retrans           = 2;
2021         args->acregmin          = 3;
2022         args->acregmax          = 60;
2023         args->acdirmin          = 30;
2024         args->acdirmax          = 60;
2025         args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
2026         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
2027
2028         switch (data->version) {
2029         case 1:
2030                 ap = (struct sockaddr_in *)&args->nfs_server.address;
2031                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2032                         goto out_no_address;
2033                 if (data->host_addrlen == 0)
2034                         goto out_no_address;
2035                 args->nfs_server.addrlen = data->host_addrlen;
2036                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
2037                         return -EFAULT;
2038                 if (!nfs_verify_server_address((struct sockaddr *)
2039                                                 &args->nfs_server.address))
2040                         goto out_no_address;
2041
2042                 switch (data->auth_flavourlen) {
2043                 case 0:
2044                         args->auth_flavors[0] = RPC_AUTH_UNIX;
2045                         break;
2046                 case 1:
2047                         if (copy_from_user(&args->auth_flavors[0],
2048                                            data->auth_flavours,
2049                                            sizeof(args->auth_flavors[0])))
2050                                 return -EFAULT;
2051                         break;
2052                 default:
2053                         goto out_inval_auth;
2054                 }
2055
2056                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2057                 if (IS_ERR(c))
2058                         return PTR_ERR(c);
2059                 args->nfs_server.hostname = c;
2060
2061                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2062                 if (IS_ERR(c))
2063                         return PTR_ERR(c);
2064                 args->nfs_server.export_path = c;
2065                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2066
2067                 c = strndup_user(data->client_addr.data, 16);
2068                 if (IS_ERR(c))
2069                         return PTR_ERR(c);
2070                 args->client_address = c;
2071
2072                 /*
2073                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2074                  * can deal with.
2075                  */
2076
2077                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2078                 args->rsize     = data->rsize;
2079                 args->wsize     = data->wsize;
2080                 args->timeo     = data->timeo;
2081                 args->retrans   = data->retrans;
2082                 args->acregmin  = data->acregmin;
2083                 args->acregmax  = data->acregmax;
2084                 args->acdirmin  = data->acdirmin;
2085                 args->acdirmax  = data->acdirmax;
2086                 args->nfs_server.protocol = data->proto;
2087
2088                 break;
2089         default: {
2090                 int status;
2091
2092                 if (nfs_parse_mount_options((char *)options, args) == 0)
2093                         return -EINVAL;
2094
2095                 if (!nfs_verify_server_address((struct sockaddr *)
2096                                                 &args->nfs_server.address))
2097                         return -EINVAL;
2098
2099                 switch (args->auth_flavor_len) {
2100                 case 0:
2101                         args->auth_flavors[0] = RPC_AUTH_UNIX;
2102                         break;
2103                 case 1:
2104                         break;
2105                 default:
2106                         goto out_inval_auth;
2107                 }
2108
2109                 if (args->client_address == NULL)
2110                         goto out_no_client_address;
2111
2112                 status = nfs_parse_devname(dev_name,
2113                                            &args->nfs_server.hostname,
2114                                            NFS4_MAXNAMLEN,
2115                                            &args->nfs_server.export_path,
2116                                            NFS4_MAXPATHLEN);
2117                 if (status < 0)
2118                         return status;
2119
2120                 break;
2121                 }
2122         }
2123
2124         return 0;
2125
2126 out_no_data:
2127         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2128         return -EINVAL;
2129
2130 out_inval_auth:
2131         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2132                  data->auth_flavourlen);
2133         return -EINVAL;
2134
2135 out_no_address:
2136         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2137         return -EINVAL;
2138
2139 out_no_client_address:
2140         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
2141         return -EINVAL;
2142 }
2143
2144 /*
2145  * Get the superblock for an NFS4 mountpoint
2146  */
2147 static int nfs4_get_sb(struct file_system_type *fs_type,
2148         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2149 {
2150         struct nfs_parsed_mount_data *data;
2151         struct super_block *s;
2152         struct nfs_server *server;
2153         struct nfs_fh *mntfh;
2154         struct dentry *mntroot;
2155         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2156         struct nfs_sb_mountdata sb_mntdata = {
2157                 .mntflags = flags,
2158         };
2159         int error = -ENOMEM;
2160
2161         data = kzalloc(sizeof(*data), GFP_KERNEL);
2162         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2163         if (data == NULL || mntfh == NULL)
2164                 goto out_free_fh;
2165
2166         security_init_mnt_opts(&data->lsm_opts);
2167
2168         /* Validate the mount data */
2169         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2170         if (error < 0)
2171                 goto out;
2172
2173         /* Get a volume representation */
2174         server = nfs4_create_server(data, mntfh);
2175         if (IS_ERR(server)) {
2176                 error = PTR_ERR(server);
2177                 goto out;
2178         }
2179         sb_mntdata.server = server;
2180
2181         if (server->flags & NFS4_MOUNT_UNSHARED)
2182                 compare_super = NULL;
2183
2184         /* Get a superblock - note that we may end up sharing one that already exists */
2185         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2186         if (IS_ERR(s)) {
2187                 error = PTR_ERR(s);
2188                 goto out_free;
2189         }
2190
2191         if (s->s_fs_info != server) {
2192                 nfs_free_server(server);
2193                 server = NULL;
2194         } else {
2195                 error = nfs_bdi_register(server);
2196                 if (error)
2197                         goto error_splat_super;
2198         }
2199
2200         if (!s->s_root) {
2201                 /* initial superblock/root creation */
2202                 nfs4_fill_super(s);
2203         }
2204
2205         mntroot = nfs4_get_root(s, mntfh);
2206         if (IS_ERR(mntroot)) {
2207                 error = PTR_ERR(mntroot);
2208                 goto error_splat_super;
2209         }
2210
2211         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2212         if (error)
2213                 goto error_splat_root;
2214
2215         s->s_flags |= MS_ACTIVE;
2216         mnt->mnt_sb = s;
2217         mnt->mnt_root = mntroot;
2218         error = 0;
2219
2220 out:
2221         kfree(data->client_address);
2222         kfree(data->nfs_server.export_path);
2223         kfree(data->nfs_server.hostname);
2224         security_free_mnt_opts(&data->lsm_opts);
2225 out_free_fh:
2226         kfree(mntfh);
2227         kfree(data);
2228         return error;
2229
2230 out_free:
2231         nfs_free_server(server);
2232         goto out;
2233
2234 error_splat_root:
2235         dput(mntroot);
2236 error_splat_super:
2237         up_write(&s->s_umount);
2238         deactivate_super(s);
2239         goto out;
2240 }
2241
2242 static void nfs4_kill_super(struct super_block *sb)
2243 {
2244         struct nfs_server *server = NFS_SB(sb);
2245
2246         nfs_return_all_delegations(sb);
2247         kill_anon_super(sb);
2248
2249         nfs4_renewd_prepare_shutdown(server);
2250         nfs_free_server(server);
2251 }
2252
2253 /*
2254  * Clone an NFS4 server record on xdev traversal (FSID-change)
2255  */
2256 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2257                             const char *dev_name, void *raw_data,
2258                             struct vfsmount *mnt)
2259 {
2260         struct nfs_clone_mount *data = raw_data;
2261         struct super_block *s;
2262         struct nfs_server *server;
2263         struct dentry *mntroot;
2264         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2265         struct nfs_sb_mountdata sb_mntdata = {
2266                 .mntflags = flags,
2267         };
2268         int error;
2269
2270         dprintk("--> nfs4_xdev_get_sb()\n");
2271
2272         /* create a new volume representation */
2273         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2274         if (IS_ERR(server)) {
2275                 error = PTR_ERR(server);
2276                 goto out_err_noserver;
2277         }
2278         sb_mntdata.server = server;
2279
2280         if (server->flags & NFS4_MOUNT_UNSHARED)
2281                 compare_super = NULL;
2282
2283         /* Get a superblock - note that we may end up sharing one that already exists */
2284         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2285         if (IS_ERR(s)) {
2286                 error = PTR_ERR(s);
2287                 goto out_err_nosb;
2288         }
2289
2290         if (s->s_fs_info != server) {
2291                 nfs_free_server(server);
2292                 server = NULL;
2293         } else {
2294                 error = nfs_bdi_register(server);
2295                 if (error)
2296                         goto error_splat_super;
2297         }
2298
2299         if (!s->s_root) {
2300                 /* initial superblock/root creation */
2301                 nfs4_clone_super(s, data->sb);
2302         }
2303
2304         mntroot = nfs4_get_root(s, data->fh);
2305         if (IS_ERR(mntroot)) {
2306                 error = PTR_ERR(mntroot);
2307                 goto error_splat_super;
2308         }
2309         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2310                 dput(mntroot);
2311                 error = -ESTALE;
2312                 goto error_splat_super;
2313         }
2314
2315         s->s_flags |= MS_ACTIVE;
2316         mnt->mnt_sb = s;
2317         mnt->mnt_root = mntroot;
2318
2319         security_sb_clone_mnt_opts(data->sb, s);
2320
2321         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2322         return 0;
2323
2324 out_err_nosb:
2325         nfs_free_server(server);
2326 out_err_noserver:
2327         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2328         return error;
2329
2330 error_splat_super:
2331         up_write(&s->s_umount);
2332         deactivate_super(s);
2333         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2334         return error;
2335 }
2336
2337 /*
2338  * Create an NFS4 server record on referral traversal
2339  */
2340 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2341                                 const char *dev_name, void *raw_data,
2342                                 struct vfsmount *mnt)
2343 {
2344         struct nfs_clone_mount *data = raw_data;
2345         struct super_block *s;
2346         struct nfs_server *server;
2347         struct dentry *mntroot;
2348         struct nfs_fh mntfh;
2349         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2350         struct nfs_sb_mountdata sb_mntdata = {
2351                 .mntflags = flags,
2352         };
2353         int error;
2354
2355         dprintk("--> nfs4_referral_get_sb()\n");
2356
2357         /* create a new volume representation */
2358         server = nfs4_create_referral_server(data, &mntfh);
2359         if (IS_ERR(server)) {
2360                 error = PTR_ERR(server);
2361                 goto out_err_noserver;
2362         }
2363         sb_mntdata.server = server;
2364
2365         if (server->flags & NFS4_MOUNT_UNSHARED)
2366                 compare_super = NULL;
2367
2368         /* Get a superblock - note that we may end up sharing one that already exists */
2369         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2370         if (IS_ERR(s)) {
2371                 error = PTR_ERR(s);
2372                 goto out_err_nosb;
2373         }
2374
2375         if (s->s_fs_info != server) {
2376                 nfs_free_server(server);
2377                 server = NULL;
2378         } else {
2379                 error = nfs_bdi_register(server);
2380                 if (error)
2381                         goto error_splat_super;
2382         }
2383
2384         if (!s->s_root) {
2385                 /* initial superblock/root creation */
2386                 nfs4_fill_super(s);
2387         }
2388
2389         mntroot = nfs4_get_root(s, &mntfh);
2390         if (IS_ERR(mntroot)) {
2391                 error = PTR_ERR(mntroot);
2392                 goto error_splat_super;
2393         }
2394         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2395                 dput(mntroot);
2396                 error = -ESTALE;
2397                 goto error_splat_super;
2398         }
2399
2400         s->s_flags |= MS_ACTIVE;
2401         mnt->mnt_sb = s;
2402         mnt->mnt_root = mntroot;
2403
2404         security_sb_clone_mnt_opts(data->sb, s);
2405
2406         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2407         return 0;
2408
2409 out_err_nosb:
2410         nfs_free_server(server);
2411 out_err_noserver:
2412         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2413         return error;
2414
2415 error_splat_super:
2416         up_write(&s->s_umount);
2417         deactivate_super(s);
2418         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2419         return error;
2420 }
2421
2422 #endif /* CONFIG_NFS_V4 */