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_intr, Opt_nointr,
  69         Opt_posix, Opt_noposix,
  70         Opt_cto, Opt_nocto,
  71         Opt_ac, Opt_noac,
  72         Opt_lock, Opt_nolock,
  73         Opt_v2, Opt_v3,
  74         Opt_udp, Opt_tcp, Opt_rdma,
  75         Opt_acl, Opt_noacl,
  76         Opt_rdirplus, Opt_nordirplus,
  77         Opt_sharecache, Opt_nosharecache,
  78
  79         /* Mount options that take integer arguments */
  80         Opt_port,
  81         Opt_rsize, Opt_wsize, Opt_bsize,
  82         Opt_timeo, Opt_retrans,
  83         Opt_acregmin, Opt_acregmax,
  84         Opt_acdirmin, Opt_acdirmax,
  85         Opt_actimeo,
  86         Opt_namelen,
  87         Opt_mountport,
  88         Opt_mountvers,
  89         Opt_nfsvers,
  90
  91         /* Mount options that take string arguments */
  92         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
  93         Opt_addr, Opt_mountaddr, Opt_clientaddr,
  94
  95         /* Mount options that are ignored */
  96         Opt_userspace, Opt_deprecated,
  97
  98         Opt_err
  99 };
 100
 101 static match_table_t nfs_mount_option_tokens = {
 102         { Opt_userspace, "bg" },
 103         { Opt_userspace, "fg" },
 104         { Opt_soft, "soft" },
 105         { Opt_hard, "hard" },
 106         { Opt_intr, "intr" },
 107         { Opt_nointr, "nointr" },
 108         { Opt_posix, "posix" },
 109         { Opt_noposix, "noposix" },
 110         { Opt_cto, "cto" },
 111         { Opt_nocto, "nocto" },
 112         { Opt_ac, "ac" },
 113         { Opt_noac, "noac" },
 114         { Opt_lock, "lock" },
 115         { Opt_nolock, "nolock" },
 116         { Opt_v2, "v2" },
 117         { Opt_v3, "v3" },
 118         { Opt_udp, "udp" },
 119         { Opt_tcp, "tcp" },
 120         { Opt_rdma, "rdma" },
 121         { Opt_acl, "acl" },
 122         { Opt_noacl, "noacl" },
 123         { Opt_rdirplus, "rdirplus" },
 124         { Opt_nordirplus, "nordirplus" },
 125         { Opt_sharecache, "sharecache" },
 126         { Opt_nosharecache, "nosharecache" },
 127
 128         { Opt_port, "port=%u" },
 129         { Opt_rsize, "rsize=%u" },
 130         { Opt_wsize, "wsize=%u" },
 131         { Opt_bsize, "bsize=%u" },
 132         { Opt_timeo, "timeo=%u" },
 133         { Opt_retrans, "retrans=%u" },
 134         { Opt_acregmin, "acregmin=%u" },
 135         { Opt_acregmax, "acregmax=%u" },
 136         { Opt_acdirmin, "acdirmin=%u" },
 137         { Opt_acdirmax, "acdirmax=%u" },
 138         { Opt_actimeo, "actimeo=%u" },
 139         { Opt_userspace, "retry=%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 vfsmount *, int);
 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
 211 static struct file_system_type nfs_fs_type = {
 212         .owner          = THIS_MODULE,
 213         .name           = "nfs",
 214         .get_sb         = nfs_get_sb,
 215         .kill_sb        = nfs_kill_super,
 216         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 217 };
 218
 219 struct file_system_type nfs_xdev_fs_type = {
 220         .owner          = THIS_MODULE,
 221         .name           = "nfs",
 222         .get_sb         = nfs_xdev_get_sb,
 223         .kill_sb        = nfs_kill_super,
 224         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 225 };
 226
 227 static const struct super_operations nfs_sops = {
 228         .alloc_inode    = nfs_alloc_inode,
 229         .destroy_inode  = nfs_destroy_inode,
 230         .write_inode    = nfs_write_inode,
 231         .put_super      = nfs_put_super,
 232         .statfs         = nfs_statfs,
 233         .clear_inode    = nfs_clear_inode,
 234         .umount_begin   = nfs_umount_begin,
 235         .show_options   = nfs_show_options,
 236         .show_stats     = nfs_show_stats,
 237 };
 238
 239 #ifdef CONFIG_NFS_V4
 240 static int nfs4_get_sb(struct file_system_type *fs_type,
 241         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 242 static int nfs4_xdev_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_referral_get_sb(struct file_system_type *fs_type,
 245         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 246 static void nfs4_kill_super(struct super_block *sb);
 247
 248 static struct file_system_type nfs4_fs_type = {
 249         .owner          = THIS_MODULE,
 250         .name           = "nfs4",
 251         .get_sb         = nfs4_get_sb,
 252         .kill_sb        = nfs4_kill_super,
 253         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 254 };
 255
 256 struct file_system_type nfs4_xdev_fs_type = {
 257         .owner          = THIS_MODULE,
 258         .name           = "nfs4",
 259         .get_sb         = nfs4_xdev_get_sb,
 260         .kill_sb        = nfs4_kill_super,
 261         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 262 };
 263
 264 struct file_system_type nfs4_referral_fs_type = {
 265         .owner          = THIS_MODULE,
 266         .name           = "nfs4",
 267         .get_sb         = nfs4_referral_get_sb,
 268         .kill_sb        = nfs4_kill_super,
 269         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 270 };
 271
 272 static const struct super_operations nfs4_sops = {
 273         .alloc_inode    = nfs_alloc_inode,
 274         .destroy_inode  = nfs_destroy_inode,
 275         .write_inode    = nfs_write_inode,
 276         .statfs         = nfs_statfs,
 277         .clear_inode    = nfs4_clear_inode,
 278         .umount_begin   = nfs_umount_begin,
 279         .show_options   = nfs_show_options,
 280         .show_stats     = nfs_show_stats,
 281 };
 282 #endif
 283
 284 static struct shrinker acl_shrinker = {
 285         .shrink         = nfs_access_cache_shrinker,
 286         .seeks          = DEFAULT_SEEKS,
 287 };
 288
 289 /*
 290  * Register the NFS filesystems
 291  */
 292 int __init register_nfs_fs(void)
 293 {
 294         int ret;
 295
 296         ret = register_filesystem(&nfs_fs_type);
 297         if (ret < 0)
 298                 goto error_0;
 299
 300         ret = nfs_register_sysctl();
 301         if (ret < 0)
 302                 goto error_1;
 303 #ifdef CONFIG_NFS_V4
 304         ret = register_filesystem(&nfs4_fs_type);
 305         if (ret < 0)
 306                 goto error_2;
 307 #endif
 308         register_shrinker(&acl_shrinker);
 309         return 0;
 310
 311 #ifdef CONFIG_NFS_V4
 312 error_2:
 313         nfs_unregister_sysctl();
 314 #endif
 315 error_1:
 316         unregister_filesystem(&nfs_fs_type);
 317 error_0:
 318         return ret;
 319 }
 320
 321 /*
 322  * Unregister the NFS filesystems
 323  */
 324 void __exit unregister_nfs_fs(void)
 325 {
 326         unregister_shrinker(&acl_shrinker);
 327 #ifdef CONFIG_NFS_V4
 328         unregister_filesystem(&nfs4_fs_type);
 329 #endif
 330         nfs_unregister_sysctl();
 331         unregister_filesystem(&nfs_fs_type);
 332 }
 333
 334 void nfs_sb_active(struct nfs_server *server)
 335 {
 336         atomic_inc(&server->active);
 337 }
 338
 339 void nfs_sb_deactive(struct nfs_server *server)
 340 {
 341         if (atomic_dec_and_test(&server->active))
 342                 wake_up(&server->active_wq);
 343 }
 344
 345 static void nfs_put_super(struct super_block *sb)
 346 {
 347         struct nfs_server *server = NFS_SB(sb);
 348         /*
 349          * Make sure there are no outstanding ops to this server.
 350          * If so, wait for them to finish before allowing the
 351          * unmount to continue.
 352          */
 353         wait_event(server->active_wq, atomic_read(&server->active) == 0);
 354 }
 355
 356 /*
 357  * Deliver file system statistics to userspace
 358  */
 359 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 360 {
 361         struct nfs_server *server = NFS_SB(dentry->d_sb);
 362         unsigned char blockbits;
 363         unsigned long blockres;
 364         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 365         struct nfs_fattr fattr;
 366         struct nfs_fsstat res = {
 367                         .fattr = &fattr,
 368         };
 369         int error;
 370
 371         lock_kernel();
 372
 373         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 374         if (error < 0)
 375                 goto out_err;
 376         buf->f_type = NFS_SUPER_MAGIC;
 377
 378         /*
 379          * Current versions of glibc do not correctly handle the
 380          * case where f_frsize != f_bsize.  Eventually we want to
 381          * report the value of wtmult in this field.
 382          */
 383         buf->f_frsize = dentry->d_sb->s_blocksize;
 384
 385         /*
 386          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 387          * are reported in units of f_frsize.  Linux hasn't had
 388          * an f_frsize field in its statfs struct until recently,
 389          * thus historically Linux's sys_statfs reports these
 390          * fields in units of f_bsize.
 391          */
 392         buf->f_bsize = dentry->d_sb->s_blocksize;
 393         blockbits = dentry->d_sb->s_blocksize_bits;
 394         blockres = (1 << blockbits) - 1;
 395         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 396         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 397         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 398
 399         buf->f_files = res.tfiles;
 400         buf->f_ffree = res.afiles;
 401
 402         buf->f_namelen = server->namelen;
 403
 404         unlock_kernel();
 405         return 0;
 406
 407  out_err:
 408         dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
 409         unlock_kernel();
 410         return error;
 411 }
 412
 413 /*
 414  * Map the security flavour number to a name
 415  */
 416 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 417 {
 418         static const struct {
 419                 rpc_authflavor_t flavour;
 420                 const char *str;
 421         } sec_flavours[] = {
 422                 { RPC_AUTH_NULL, "null" },
 423                 { RPC_AUTH_UNIX, "sys" },
 424                 { RPC_AUTH_GSS_KRB5, "krb5" },
 425                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 426                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 427                 { RPC_AUTH_GSS_LKEY, "lkey" },
 428                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 429                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 430                 { RPC_AUTH_GSS_SPKM, "spkm" },
 431                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 432                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 433                 { UINT_MAX, "unknown" }
 434         };
 435         int i;
 436
 437         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 438                 if (sec_flavours[i].flavour == flavour)
 439                         break;
 440         }
 441         return sec_flavours[i].str;
 442 }
 443
 444 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 445                                     int showdefaults)
 446 {
 447         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 448
 449         switch (sap->sa_family) {
 450         case AF_INET: {
 451                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 452                 seq_printf(m, ",mountaddr=" NIPQUAD_FMT,
 453                                 NIPQUAD(sin->sin_addr.s_addr));
 454                 break;
 455         }
 456         case AF_INET6: {
 457                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 458                 seq_printf(m, ",mountaddr=" NIP6_FMT,
 459                                 NIP6(sin6->sin6_addr));
 460                 break;
 461         }
 462         default:
 463                 if (showdefaults)
 464                         seq_printf(m, ",mountaddr=unspecified");
 465         }
 466
 467         if (nfss->mountd_version || showdefaults)
 468                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 469         if (nfss->mountd_port || showdefaults)
 470                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 471
 472         switch (nfss->mountd_protocol) {
 473         case IPPROTO_UDP:
 474                 seq_printf(m, ",mountproto=udp");
 475                 break;
 476         case IPPROTO_TCP:
 477                 seq_printf(m, ",mountproto=tcp");
 478                 break;
 479         default:
 480                 if (showdefaults)
 481                         seq_printf(m, ",mountproto=auto");
 482         }
 483 }
 484
 485 /*
 486  * Describe the mount options in force on this server representation
 487  */
 488 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 489                                    int showdefaults)
 490 {
 491         static const struct proc_nfs_info {
 492                 int flag;
 493                 const char *str;
 494                 const char *nostr;
 495         } nfs_info[] = {
 496                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 497                 { NFS_MOUNT_INTR, ",intr", ",nointr" },
 498                 { NFS_MOUNT_POSIX, ",posix", "" },
 499                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 500                 { NFS_MOUNT_NOAC, ",noac", "" },
 501                 { NFS_MOUNT_NONLM, ",nolock", "" },
 502                 { NFS_MOUNT_NOACL, ",noacl", "" },
 503                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 504                 { NFS_MOUNT_UNSHARED, ",nosharecache", ""},
 505                 { 0, NULL, NULL }
 506         };
 507         const struct proc_nfs_info *nfs_infop;
 508         struct nfs_client *clp = nfss->nfs_client;
 509         u32 version = clp->rpc_ops->version;
 510
 511         seq_printf(m, ",vers=%u", version);
 512         seq_printf(m, ",rsize=%u", nfss->rsize);
 513         seq_printf(m, ",wsize=%u", nfss->wsize);
 514         if (nfss->bsize != 0)
 515                 seq_printf(m, ",bsize=%u", nfss->bsize);
 516         seq_printf(m, ",namlen=%u", nfss->namelen);
 517         if (nfss->acregmin != 3*HZ || showdefaults)
 518                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 519         if (nfss->acregmax != 60*HZ || showdefaults)
 520                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 521         if (nfss->acdirmin != 30*HZ || showdefaults)
 522                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 523         if (nfss->acdirmax != 60*HZ || showdefaults)
 524                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 525         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 526                 if (nfss->flags & nfs_infop->flag)
 527                         seq_puts(m, nfs_infop->str);
 528                 else
 529                         seq_puts(m, nfs_infop->nostr);
 530         }
 531         seq_printf(m, ",proto=%s",
 532                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 533         if (version == 4) {
 534                 if (nfss->port != NFS_PORT)
 535                         seq_printf(m, ",port=%u", nfss->port);
 536         } else
 537                 if (nfss->port)
 538                         seq_printf(m, ",port=%u", nfss->port);
 539
 540         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 541         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 542         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 543
 544         if (version != 4)
 545                 nfs_show_mountd_options(m, nfss, showdefaults);
 546
 547 #ifdef CONFIG_NFS_V4
 548         if (clp->rpc_ops->version == 4)
 549                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 550 #endif
 551 }
 552
 553 /*
 554  * Describe the mount options on this VFS mountpoint
 555  */
 556 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 557 {
 558         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 559
 560         nfs_show_mount_options(m, nfss, 0);
 561
 562         seq_printf(m, ",addr=%s",
 563                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 564                                                         RPC_DISPLAY_ADDR));
 565
 566         return 0;
 567 }
 568
 569 /*
 570  * Present statistical information for this VFS mountpoint
 571  */
 572 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 573 {
 574         int i, cpu;
 575         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 576         struct rpc_auth *auth = nfss->client->cl_auth;
 577         struct nfs_iostats totals = { };
 578
 579         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 580
 581         /*
 582          * Display all mount option settings
 583          */
 584         seq_printf(m, "\n\topts:\t");
 585         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 586         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 587         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 588         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 589         nfs_show_mount_options(m, nfss, 1);
 590
 591         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 592
 593         seq_printf(m, "\n\tcaps:\t");
 594         seq_printf(m, "caps=0x%x", nfss->caps);
 595         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 596         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 597         seq_printf(m, ",bsize=%u", nfss->bsize);
 598         seq_printf(m, ",namlen=%u", nfss->namelen);
 599
 600 #ifdef CONFIG_NFS_V4
 601         if (nfss->nfs_client->rpc_ops->version == 4) {
 602                 seq_printf(m, "\n\tnfsv4:\t");
 603                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 604                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 605                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 606         }
 607 #endif
 608
 609         /*
 610          * Display security flavor in effect for this mount
 611          */
 612         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 613         if (auth->au_flavor)
 614                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 615
 616         /*
 617          * Display superblock I/O counters
 618          */
 619         for_each_possible_cpu(cpu) {
 620                 struct nfs_iostats *stats;
 621
 622                 preempt_disable();
 623                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 624
 625                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 626                         totals.events[i] += stats->events[i];
 627                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 628                         totals.bytes[i] += stats->bytes[i];
 629
 630                 preempt_enable();
 631         }
 632
 633         seq_printf(m, "\n\tevents:\t");
 634         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 635                 seq_printf(m, "%lu ", totals.events[i]);
 636         seq_printf(m, "\n\tbytes:\t");
 637         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 638                 seq_printf(m, "%Lu ", totals.bytes[i]);
 639         seq_printf(m, "\n");
 640
 641         rpc_print_iostats(m, nfss->client);
 642
 643         return 0;
 644 }
 645
 646 /*
 647  * Begin unmount by attempting to remove all automounted mountpoints we added
 648  * in response to xdev traversals and referrals
 649  */
 650 static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
 651 {
 652         struct nfs_server *server = NFS_SB(vfsmnt->mnt_sb);
 653         struct rpc_clnt *rpc;
 654
 655         if (!(flags & MNT_FORCE))
 656                 return;
 657         /* -EIO all pending I/O */
 658         rpc = server->client_acl;
 659         if (!IS_ERR(rpc))
 660                 rpc_killall_tasks(rpc);
 661         rpc = server->client;
 662         if (!IS_ERR(rpc))
 663                 rpc_killall_tasks(rpc);
 664 }
 665
 666 /*
 667  * Set the port number in an address.  Be agnostic about the address family.
 668  */
 669 static void nfs_set_port(struct sockaddr *sap, unsigned short port)
 670 {
 671         switch (sap->sa_family) {
 672         case AF_INET: {
 673                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 674                 ap->sin_port = htons(port);
 675                 break;
 676         }
 677         case AF_INET6: {
 678                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 679                 ap->sin6_port = htons(port);
 680                 break;
 681         }
 682         }
 683 }
 684
 685 /*
 686  * Sanity-check a server address provided by the mount command.
 687  *
 688  * Address family must be initialized, and address must not be
 689  * the ANY address for that family.
 690  */
 691 static int nfs_verify_server_address(struct sockaddr *addr)
 692 {
 693         switch (addr->sa_family) {
 694         case AF_INET: {
 695                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 696                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 697         }
 698         case AF_INET6: {
 699                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 700                 return !ipv6_addr_any(sa);
 701         }
 702         }
 703
 704         return 0;
 705 }
 706
 707 /*
 708  * Parse string addresses passed in via a mount option,
 709  * and construct a sockaddr based on the result.
 710  *
 711  * If address parsing fails, set the sockaddr's address
 712  * family to AF_UNSPEC to force nfs_verify_server_address()
 713  * to punt the mount.
 714  */
 715 static void nfs_parse_server_address(char *value,
 716                                      struct sockaddr *sap,
 717                                      size_t *len)
 718 {
 719         if (strchr(value, ':')) {
 720                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 721                 u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
 722
 723                 ap->sin6_family = AF_INET6;
 724                 *len = sizeof(*ap);
 725                 if (in6_pton(value, -1, addr, '\0', NULL))
 726                         return;
 727         } else {
 728                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 729                 u8 *addr = (u8 *)&ap->sin_addr.s_addr;
 730
 731                 ap->sin_family = AF_INET;
 732                 *len = sizeof(*ap);
 733                 if (in4_pton(value, -1, addr, '\0', NULL))
 734                         return;
 735         }
 736
 737         sap->sa_family = AF_UNSPEC;
 738         *len = 0;
 739 }
 740
 741 /*
 742  * Error-check and convert a string of mount options from user space into
 743  * a data structure
 744  */
 745 static int nfs_parse_mount_options(char *raw,
 746                                    struct nfs_parsed_mount_data *mnt)
 747 {
 748         char *p, *string, *secdata;
 749         int rc;
 750
 751         if (!raw) {
 752                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 753                 return 1;
 754         }
 755         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 756
 757         secdata = alloc_secdata();
 758         if (!secdata)
 759                 goto out_nomem;
 760
 761         rc = security_sb_copy_data(raw, secdata);
 762         if (rc)
 763                 goto out_security_failure;
 764
 765         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 766         if (rc)
 767                 goto out_security_failure;
 768
 769         free_secdata(secdata);
 770
 771         while ((p = strsep(&raw, ",")) != NULL) {
 772                 substring_t args[MAX_OPT_ARGS];
 773                 int option, token;
 774
 775                 if (!*p)
 776                         continue;
 777
 778                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 779
 780                 token = match_token(p, nfs_mount_option_tokens, args);
 781                 switch (token) {
 782                 case Opt_soft:
 783                         mnt->flags |= NFS_MOUNT_SOFT;
 784                         break;
 785                 case Opt_hard:
 786                         mnt->flags &= ~NFS_MOUNT_SOFT;
 787                         break;
 788                 case Opt_intr:
 789                 case Opt_nointr:
 790                         break;
 791                 case Opt_posix:
 792                         mnt->flags |= NFS_MOUNT_POSIX;
 793                         break;
 794                 case Opt_noposix:
 795                         mnt->flags &= ~NFS_MOUNT_POSIX;
 796                         break;
 797                 case Opt_cto:
 798                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 799                         break;
 800                 case Opt_nocto:
 801                         mnt->flags |= NFS_MOUNT_NOCTO;
 802                         break;
 803                 case Opt_ac:
 804                         mnt->flags &= ~NFS_MOUNT_NOAC;
 805                         break;
 806                 case Opt_noac:
 807                         mnt->flags |= NFS_MOUNT_NOAC;
 808                         break;
 809                 case Opt_lock:
 810                         mnt->flags &= ~NFS_MOUNT_NONLM;
 811                         break;
 812                 case Opt_nolock:
 813                         mnt->flags |= NFS_MOUNT_NONLM;
 814                         break;
 815                 case Opt_v2:
 816                         mnt->flags &= ~NFS_MOUNT_VER3;
 817                         break;
 818                 case Opt_v3:
 819                         mnt->flags |= NFS_MOUNT_VER3;
 820                         break;
 821                 case Opt_udp:
 822                         mnt->flags &= ~NFS_MOUNT_TCP;
 823                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 824                         mnt->timeo = 7;
 825                         mnt->retrans = 5;
 826                         break;
 827                 case Opt_tcp:
 828                         mnt->flags |= NFS_MOUNT_TCP;
 829                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 830                         mnt->timeo = 600;
 831                         mnt->retrans = 2;
 832                         break;
 833                 case Opt_rdma:
 834                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 835                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 836                         mnt->timeo = 600;
 837                         mnt->retrans = 2;
 838                         break;
 839                 case Opt_acl:
 840                         mnt->flags &= ~NFS_MOUNT_NOACL;
 841                         break;
 842                 case Opt_noacl:
 843                         mnt->flags |= NFS_MOUNT_NOACL;
 844                         break;
 845                 case Opt_rdirplus:
 846                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 847                         break;
 848                 case Opt_nordirplus:
 849                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 850                         break;
 851                 case Opt_sharecache:
 852                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 853                         break;
 854                 case Opt_nosharecache:
 855                         mnt->flags |= NFS_MOUNT_UNSHARED;
 856                         break;
 857
 858                 case Opt_port:
 859                         if (match_int(args, &option))
 860                                 return 0;
 861                         if (option < 0 || option > 65535)
 862                                 return 0;
 863                         mnt->nfs_server.port = option;
 864                         break;
 865                 case Opt_rsize:
 866                         if (match_int(args, &mnt->rsize))
 867                                 return 0;
 868                         break;
 869                 case Opt_wsize:
 870                         if (match_int(args, &mnt->wsize))
 871                                 return 0;
 872                         break;
 873                 case Opt_bsize:
 874                         if (match_int(args, &option))
 875                                 return 0;
 876                         if (option < 0)
 877                                 return 0;
 878                         mnt->bsize = option;
 879                         break;
 880                 case Opt_timeo:
 881                         if (match_int(args, &mnt->timeo))
 882                                 return 0;
 883                         break;
 884                 case Opt_retrans:
 885                         if (match_int(args, &mnt->retrans))
 886                                 return 0;
 887                         break;
 888                 case Opt_acregmin:
 889                         if (match_int(args, &mnt->acregmin))
 890                                 return 0;
 891                         break;
 892                 case Opt_acregmax:
 893                         if (match_int(args, &mnt->acregmax))
 894                                 return 0;
 895                         break;
 896                 case Opt_acdirmin:
 897                         if (match_int(args, &mnt->acdirmin))
 898                                 return 0;
 899                         break;
 900                 case Opt_acdirmax:
 901                         if (match_int(args, &mnt->acdirmax))
 902                                 return 0;
 903                         break;
 904                 case Opt_actimeo:
 905                         if (match_int(args, &option))
 906                                 return 0;
 907                         if (option < 0)
 908                                 return 0;
 909                         mnt->acregmin =
 910                         mnt->acregmax =
 911                         mnt->acdirmin =
 912                         mnt->acdirmax = option;
 913                         break;
 914                 case Opt_namelen:
 915                         if (match_int(args, &mnt->namlen))
 916                                 return 0;
 917                         break;
 918                 case Opt_mountport:
 919                         if (match_int(args, &option))
 920                                 return 0;
 921                         if (option < 0 || option > 65535)
 922                                 return 0;
 923                         mnt->mount_server.port = option;
 924                         break;
 925                 case Opt_mountvers:
 926                         if (match_int(args, &option))
 927                                 return 0;
 928                         if (option < 0)
 929                                 return 0;
 930                         mnt->mount_server.version = option;
 931                         break;
 932                 case Opt_nfsvers:
 933                         if (match_int(args, &option))
 934                                 return 0;
 935                         switch (option) {
 936                         case 2:
 937                                 mnt->flags &= ~NFS_MOUNT_VER3;
 938                                 break;
 939                         case 3:
 940                                 mnt->flags |= NFS_MOUNT_VER3;
 941                                 break;
 942                         default:
 943                                 goto out_unrec_vers;
 944                         }
 945                         break;
 946
 947                 case Opt_sec:
 948                         string = match_strdup(args);
 949                         if (string == NULL)
 950                                 goto out_nomem;
 951                         token = match_token(string, nfs_secflavor_tokens, args);
 952                         kfree(string);
 953
 954                         /*
 955                          * The flags setting is for v2/v3.  The flavor_len
 956                          * setting is for v4.  v2/v3 also need to know the
 957                          * difference between NULL and UNIX.
 958                          */
 959                         switch (token) {
 960                         case Opt_sec_none:
 961                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 962                                 mnt->auth_flavor_len = 0;
 963                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 964                                 break;
 965                         case Opt_sec_sys:
 966                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 967                                 mnt->auth_flavor_len = 0;
 968                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 969                                 break;
 970                         case Opt_sec_krb5:
 971                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 972                                 mnt->auth_flavor_len = 1;
 973                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 974                                 break;
 975                         case Opt_sec_krb5i:
 976                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 977                                 mnt->auth_flavor_len = 1;
 978                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 979                                 break;
 980                         case Opt_sec_krb5p:
 981                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 982                                 mnt->auth_flavor_len = 1;
 983                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 984                                 break;
 985                         case Opt_sec_lkey:
 986                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 987                                 mnt->auth_flavor_len = 1;
 988                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 989                                 break;
 990                         case Opt_sec_lkeyi:
 991                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 992                                 mnt->auth_flavor_len = 1;
 993                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 994                                 break;
 995                         case Opt_sec_lkeyp:
 996                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 997                                 mnt->auth_flavor_len = 1;
 998                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 999                                 break;
1000                         case Opt_sec_spkm:
1001                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1002                                 mnt->auth_flavor_len = 1;
1003                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1004                                 break;
1005                         case Opt_sec_spkmi:
1006                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1007                                 mnt->auth_flavor_len = 1;
1008                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1009                                 break;
1010                         case Opt_sec_spkmp:
1011                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1012                                 mnt->auth_flavor_len = 1;
1013                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1014                                 break;
1015                         default:
1016                                 goto out_unrec_sec;
1017                         }
1018                         break;
1019                 case Opt_proto:
1020                         string = match_strdup(args);
1021                         if (string == NULL)
1022                                 goto out_nomem;
1023                         token = match_token(string,
1024                                             nfs_xprt_protocol_tokens, args);
1025                         kfree(string);
1026
1027                         switch (token) {
1028                         case Opt_xprt_udp:
1029                                 mnt->flags &= ~NFS_MOUNT_TCP;
1030                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1031                                 mnt->timeo = 7;
1032                                 mnt->retrans = 5;
1033                                 break;
1034                         case Opt_xprt_tcp:
1035                                 mnt->flags |= NFS_MOUNT_TCP;
1036                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1037                                 mnt->timeo = 600;
1038                                 mnt->retrans = 2;
1039                                 break;
1040                         case Opt_xprt_rdma:
1041                                 /* vector side protocols to TCP */
1042                                 mnt->flags |= NFS_MOUNT_TCP;
1043                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1044                                 mnt->timeo = 600;
1045                                 mnt->retrans = 2;
1046                                 break;
1047                         default:
1048                                 goto out_unrec_xprt;
1049                         }
1050                         break;
1051                 case Opt_mountproto:
1052                         string = match_strdup(args);
1053                         if (string == NULL)
1054                                 goto out_nomem;
1055                         token = match_token(string,
1056                                             nfs_xprt_protocol_tokens, args);
1057                         kfree(string);
1058
1059                         switch (token) {
1060                         case Opt_xprt_udp:
1061                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1062                                 break;
1063                         case Opt_xprt_tcp:
1064                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1065                                 break;
1066                         case Opt_xprt_rdma: /* not used for side protocols */
1067                         default:
1068                                 goto out_unrec_xprt;
1069                         }
1070                         break;
1071                 case Opt_addr:
1072                         string = match_strdup(args);
1073                         if (string == NULL)
1074                                 goto out_nomem;
1075                         nfs_parse_server_address(string, (struct sockaddr *)
1076                                                  &mnt->nfs_server.address,
1077                                                  &mnt->nfs_server.addrlen);
1078                         kfree(string);
1079                         break;
1080                 case Opt_clientaddr:
1081                         string = match_strdup(args);
1082                         if (string == NULL)
1083                                 goto out_nomem;
1084                         kfree(mnt->client_address);
1085                         mnt->client_address = string;
1086                         break;
1087                 case Opt_mounthost:
1088                         string = match_strdup(args);
1089                         if (string == NULL)
1090                                 goto out_nomem;
1091                         kfree(mnt->mount_server.hostname);
1092                         mnt->mount_server.hostname = string;
1093                         break;
1094                 case Opt_mountaddr:
1095                         string = match_strdup(args);
1096                         if (string == NULL)
1097                                 goto out_nomem;
1098                         nfs_parse_server_address(string, (struct sockaddr *)
1099                                                  &mnt->mount_server.address,
1100                                                  &mnt->mount_server.addrlen);
1101                         kfree(string);
1102                         break;
1103
1104                 case Opt_userspace:
1105                 case Opt_deprecated:
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",
1194                         hostname, status);
1195         return status;
1196 }
1197
1198 /*
1199  * Validate the NFS2/NFS3 mount data
1200  * - fills in the mount root filehandle
1201  *
1202  * For option strings, user space handles the following behaviors:
1203  *
1204  * + DNS: mapping server host name to IP address ("addr=" option)
1205  *
1206  * + failure mode: how to behave if a mount request can't be handled
1207  *   immediately ("fg/bg" option)
1208  *
1209  * + retry: how often to retry a mount request ("retry=" option)
1210  *
1211  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1212  *   mountproto=tcp after mountproto=udp, and so on
1213  */
1214 static int nfs_validate_mount_data(void *options,
1215                                    struct nfs_parsed_mount_data *args,
1216                                    struct nfs_fh *mntfh,
1217                                    const char *dev_name)
1218 {
1219         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1220
1221         memset(args, 0, sizeof(*args));
1222
1223         if (data == NULL)
1224                 goto out_no_data;
1225
1226         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1227         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1228         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1229         args->timeo             = 600;
1230         args->retrans           = 2;
1231         args->acregmin          = 3;
1232         args->acregmax          = 60;
1233         args->acdirmin          = 30;
1234         args->acdirmax          = 60;
1235         args->mount_server.port = 0;    /* autobind unless user sets port */
1236         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1237         args->nfs_server.port   = 0;    /* autobind unless user sets port */
1238         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1239
1240         switch (data->version) {
1241         case 1:
1242                 data->namlen = 0;
1243         case 2:
1244                 data->bsize = 0;
1245         case 3:
1246                 if (data->flags & NFS_MOUNT_VER3)
1247                         goto out_no_v3;
1248                 data->root.size = NFS2_FHSIZE;
1249                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1250         case 4:
1251                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1252                         goto out_no_sec;
1253         case 5:
1254                 memset(data->context, 0, sizeof(data->context));
1255         case 6:
1256                 if (data->flags & NFS_MOUNT_VER3)
1257                         mntfh->size = data->root.size;
1258                 else
1259                         mntfh->size = NFS2_FHSIZE;
1260
1261                 if (mntfh->size > sizeof(mntfh->data))
1262                         goto out_invalid_fh;
1263
1264                 memcpy(mntfh->data, data->root.data, mntfh->size);
1265                 if (mntfh->size < sizeof(mntfh->data))
1266                         memset(mntfh->data + mntfh->size, 0,
1267                                sizeof(mntfh->data) - mntfh->size);
1268
1269                 /*
1270                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1271                  * can deal with.
1272                  */
1273                 args->flags             = data->flags;
1274                 args->rsize             = data->rsize;
1275                 args->wsize             = data->wsize;
1276                 args->timeo             = data->timeo;
1277                 args->retrans           = data->retrans;
1278                 args->acregmin          = data->acregmin;
1279                 args->acregmax          = data->acregmax;
1280                 args->acdirmin          = data->acdirmin;
1281                 args->acdirmax          = data->acdirmax;
1282
1283                 memcpy(&args->nfs_server.address, &data->addr,
1284                        sizeof(data->addr));
1285                 args->nfs_server.addrlen = sizeof(data->addr);
1286                 if (!nfs_verify_server_address((struct sockaddr *)
1287                                                 &args->nfs_server.address))
1288                         goto out_no_address;
1289
1290                 if (!(data->flags & NFS_MOUNT_TCP))
1291                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1292                 /* N.B. caller will free nfs_server.hostname in all cases */
1293                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1294                 args->namlen            = data->namlen;
1295                 args->bsize             = data->bsize;
1296                 args->auth_flavors[0]   = data->pseudoflavor;
1297                 if (!args->nfs_server.hostname)
1298                         goto out_nomem;
1299
1300                 /*
1301                  * The legacy version 6 binary mount data from userspace has a
1302                  * field used only to transport selinux information into the
1303                  * the kernel.  To continue to support that functionality we
1304                  * have a touch of selinux knowledge here in the NFS code. The
1305                  * userspace code converted context=blah to just blah so we are
1306                  * converting back to the full string selinux understands.
1307                  */
1308                 if (data->context[0]){
1309 #ifdef CONFIG_SECURITY_SELINUX
1310                         int rc;
1311                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1312                         if (!opts_str)
1313                                 return -ENOMEM;
1314                         strcpy(opts_str, "context=");
1315                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1316                         strcat(opts_str, &data->context[0]);
1317                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1318                         kfree(opts_str);
1319                         if (rc)
1320                                 return rc;
1321 #else
1322                         return -EINVAL;
1323 #endif
1324                 }
1325
1326                 break;
1327         default: {
1328                 unsigned int len;
1329                 char *c;
1330                 int status;
1331
1332                 if (nfs_parse_mount_options((char *)options, args) == 0)
1333                         return -EINVAL;
1334
1335                 if (!nfs_verify_server_address((struct sockaddr *)
1336                                                 &args->nfs_server.address))
1337                         goto out_no_address;
1338
1339                 c = strchr(dev_name, ':');
1340                 if (c == NULL)
1341                         return -EINVAL;
1342                 len = c - dev_name;
1343                 /* N.B. caller will free nfs_server.hostname in all cases */
1344                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1345                 if (!args->nfs_server.hostname)
1346                         goto out_nomem;
1347
1348                 c++;
1349                 if (strlen(c) > NFS_MAXPATHLEN)
1350                         return -ENAMETOOLONG;
1351                 args->nfs_server.export_path = c;
1352
1353                 status = nfs_try_mount(args, mntfh);
1354                 if (status)
1355                         return status;
1356
1357                 break;
1358                 }
1359         }
1360
1361         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1362                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1363
1364 #ifndef CONFIG_NFS_V3
1365         if (args->flags & NFS_MOUNT_VER3)
1366                 goto out_v3_not_compiled;
1367 #endif /* !CONFIG_NFS_V3 */
1368
1369         return 0;
1370
1371 out_no_data:
1372         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1373         return -EINVAL;
1374
1375 out_no_v3:
1376         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1377                  data->version);
1378         return -EINVAL;
1379
1380 out_no_sec:
1381         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1382         return -EINVAL;
1383
1384 #ifndef CONFIG_NFS_V3
1385 out_v3_not_compiled:
1386         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1387         return -EPROTONOSUPPORT;
1388 #endif /* !CONFIG_NFS_V3 */
1389
1390 out_nomem:
1391         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1392         return -ENOMEM;
1393
1394 out_no_address:
1395         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1396         return -EINVAL;
1397
1398 out_invalid_fh:
1399         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1400         return -EINVAL;
1401 }
1402
1403 /*
1404  * Initialise the common bits of the superblock
1405  */
1406 static inline void nfs_initialise_sb(struct super_block *sb)
1407 {
1408         struct nfs_server *server = NFS_SB(sb);
1409
1410         sb->s_magic = NFS_SUPER_MAGIC;
1411
1412         /* We probably want something more informative here */
1413         snprintf(sb->s_id, sizeof(sb->s_id),
1414                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1415
1416         if (sb->s_blocksize == 0)
1417                 sb->s_blocksize = nfs_block_bits(server->wsize,
1418                                                  &sb->s_blocksize_bits);
1419
1420         if (server->flags & NFS_MOUNT_NOAC)
1421                 sb->s_flags |= MS_SYNCHRONOUS;
1422
1423         nfs_super_set_maxbytes(sb, server->maxfilesize);
1424 }
1425
1426 /*
1427  * Finish setting up an NFS2/3 superblock
1428  */
1429 static void nfs_fill_super(struct super_block *sb,
1430                            struct nfs_parsed_mount_data *data)
1431 {
1432         struct nfs_server *server = NFS_SB(sb);
1433
1434         sb->s_blocksize_bits = 0;
1435         sb->s_blocksize = 0;
1436         if (data->bsize)
1437                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1438
1439         if (server->flags & NFS_MOUNT_VER3) {
1440                 /* The VFS shouldn't apply the umask to mode bits. We will do
1441                  * so ourselves when necessary.
1442                  */
1443                 sb->s_flags |= MS_POSIXACL;
1444                 sb->s_time_gran = 1;
1445         }
1446
1447         sb->s_op = &nfs_sops;
1448         nfs_initialise_sb(sb);
1449 }
1450
1451 /*
1452  * Finish setting up a cloned NFS2/3 superblock
1453  */
1454 static void nfs_clone_super(struct super_block *sb,
1455                             const struct super_block *old_sb)
1456 {
1457         struct nfs_server *server = NFS_SB(sb);
1458
1459         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1460         sb->s_blocksize = old_sb->s_blocksize;
1461         sb->s_maxbytes = old_sb->s_maxbytes;
1462
1463         if (server->flags & NFS_MOUNT_VER3) {
1464                 /* The VFS shouldn't apply the umask to mode bits. We will do
1465                  * so ourselves when necessary.
1466                  */
1467                 sb->s_flags |= MS_POSIXACL;
1468                 sb->s_time_gran = 1;
1469         }
1470
1471         sb->s_op = old_sb->s_op;
1472         nfs_initialise_sb(sb);
1473 }
1474
1475 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1476
1477 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1478 {
1479         const struct nfs_server *a = s->s_fs_info;
1480         const struct rpc_clnt *clnt_a = a->client;
1481         const struct rpc_clnt *clnt_b = b->client;
1482
1483         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1484                 goto Ebusy;
1485         if (a->nfs_client != b->nfs_client)
1486                 goto Ebusy;
1487         if (a->flags != b->flags)
1488                 goto Ebusy;
1489         if (a->wsize != b->wsize)
1490                 goto Ebusy;
1491         if (a->rsize != b->rsize)
1492                 goto Ebusy;
1493         if (a->acregmin != b->acregmin)
1494                 goto Ebusy;
1495         if (a->acregmax != b->acregmax)
1496                 goto Ebusy;
1497         if (a->acdirmin != b->acdirmin)
1498                 goto Ebusy;
1499         if (a->acdirmax != b->acdirmax)
1500                 goto Ebusy;
1501         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1502                 goto Ebusy;
1503         return 1;
1504 Ebusy:
1505         return 0;
1506 }
1507
1508 struct nfs_sb_mountdata {
1509         struct nfs_server *server;
1510         int mntflags;
1511 };
1512
1513 static int nfs_set_super(struct super_block *s, void *data)
1514 {
1515         struct nfs_sb_mountdata *sb_mntdata = data;
1516         struct nfs_server *server = sb_mntdata->server;
1517         int ret;
1518
1519         s->s_flags = sb_mntdata->mntflags;
1520         s->s_fs_info = server;
1521         ret = set_anon_super(s, server);
1522         if (ret == 0)
1523                 server->s_dev = s->s_dev;
1524         return ret;
1525 }
1526
1527 static int nfs_compare_super_address(struct nfs_server *server1,
1528                                      struct nfs_server *server2)
1529 {
1530         struct sockaddr *sap1, *sap2;
1531
1532         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1533         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1534
1535         if (sap1->sa_family != sap2->sa_family)
1536                 return 0;
1537
1538         switch (sap1->sa_family) {
1539         case AF_INET: {
1540                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1541                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1542                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1543                         return 0;
1544                 if (sin1->sin_port != sin2->sin_port)
1545                         return 0;
1546                 break;
1547         }
1548         case AF_INET6: {
1549                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1550                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1551                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1552                         return 0;
1553                 if (sin1->sin6_port != sin2->sin6_port)
1554                         return 0;
1555                 break;
1556         }
1557         default:
1558                 return 0;
1559         }
1560
1561         return 1;
1562 }
1563
1564 static int nfs_compare_super(struct super_block *sb, void *data)
1565 {
1566         struct nfs_sb_mountdata *sb_mntdata = data;
1567         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1568         int mntflags = sb_mntdata->mntflags;
1569
1570         if (!nfs_compare_super_address(old, server))
1571                 return 0;
1572         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1573         if (old->flags & NFS_MOUNT_UNSHARED)
1574                 return 0;
1575         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1576                 return 0;
1577         return nfs_compare_mount_options(sb, server, mntflags);
1578 }
1579
1580 static int nfs_get_sb(struct file_system_type *fs_type,
1581         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1582 {
1583         struct nfs_server *server = NULL;
1584         struct super_block *s;
1585         struct nfs_fh mntfh;
1586         struct nfs_parsed_mount_data data;
1587         struct dentry *mntroot;
1588         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1589         struct nfs_sb_mountdata sb_mntdata = {
1590                 .mntflags = flags,
1591         };
1592         int error;
1593
1594         security_init_mnt_opts(&data.lsm_opts);
1595
1596         /* Validate the mount data */
1597         error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);
1598         if (error < 0)
1599                 goto out;
1600
1601         /* Get a volume representation */
1602         server = nfs_create_server(&data, &mntfh);
1603         if (IS_ERR(server)) {
1604                 error = PTR_ERR(server);
1605                 goto out;
1606         }
1607         sb_mntdata.server = server;
1608
1609         if (server->flags & NFS_MOUNT_UNSHARED)
1610                 compare_super = NULL;
1611
1612         /* Get a superblock - note that we may end up sharing one that already exists */
1613         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1614         if (IS_ERR(s)) {
1615                 error = PTR_ERR(s);
1616                 goto out_err_nosb;
1617         }
1618
1619         if (s->s_fs_info != server) {
1620                 nfs_free_server(server);
1621                 server = NULL;
1622         }
1623
1624         if (!s->s_root) {
1625                 /* initial superblock/root creation */
1626                 nfs_fill_super(s, &data);
1627         }
1628
1629         mntroot = nfs_get_root(s, &mntfh);
1630         if (IS_ERR(mntroot)) {
1631                 error = PTR_ERR(mntroot);
1632                 goto error_splat_super;
1633         }
1634
1635         error = security_sb_set_mnt_opts(s, &data.lsm_opts);
1636         if (error)
1637                 goto error_splat_root;
1638
1639         s->s_flags |= MS_ACTIVE;
1640         mnt->mnt_sb = s;
1641         mnt->mnt_root = mntroot;
1642         error = 0;
1643
1644 out:
1645         kfree(data.nfs_server.hostname);
1646         kfree(data.mount_server.hostname);
1647         security_free_mnt_opts(&data.lsm_opts);
1648         return error;
1649
1650 out_err_nosb:
1651         nfs_free_server(server);
1652         goto out;
1653
1654 error_splat_root:
1655         dput(mntroot);
1656 error_splat_super:
1657         up_write(&s->s_umount);
1658         deactivate_super(s);
1659         goto out;
1660 }
1661
1662 /*
1663  * Destroy an NFS2/3 superblock
1664  */
1665 static void nfs_kill_super(struct super_block *s)
1666 {
1667         struct nfs_server *server = NFS_SB(s);
1668
1669         kill_anon_super(s);
1670         nfs_free_server(server);
1671 }
1672
1673 /*
1674  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1675  */
1676 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1677                            const char *dev_name, void *raw_data,
1678                            struct vfsmount *mnt)
1679 {
1680         struct nfs_clone_mount *data = raw_data;
1681         struct super_block *s;
1682         struct nfs_server *server;
1683         struct dentry *mntroot;
1684         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1685         struct nfs_sb_mountdata sb_mntdata = {
1686                 .mntflags = flags,
1687         };
1688         int error;
1689
1690         dprintk("--> nfs_xdev_get_sb()\n");
1691
1692         /* create a new volume representation */
1693         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1694         if (IS_ERR(server)) {
1695                 error = PTR_ERR(server);
1696                 goto out_err_noserver;
1697         }
1698         sb_mntdata.server = server;
1699
1700         if (server->flags & NFS_MOUNT_UNSHARED)
1701                 compare_super = NULL;
1702
1703         /* Get a superblock - note that we may end up sharing one that already exists */
1704         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1705         if (IS_ERR(s)) {
1706                 error = PTR_ERR(s);
1707                 goto out_err_nosb;
1708         }
1709
1710         if (s->s_fs_info != server) {
1711                 nfs_free_server(server);
1712                 server = NULL;
1713         }
1714
1715         if (!s->s_root) {
1716                 /* initial superblock/root creation */
1717                 nfs_clone_super(s, data->sb);
1718         }
1719
1720         mntroot = nfs_get_root(s, data->fh);
1721         if (IS_ERR(mntroot)) {
1722                 error = PTR_ERR(mntroot);
1723                 goto error_splat_super;
1724         }
1725         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1726                 dput(mntroot);
1727                 error = -ESTALE;
1728                 goto error_splat_super;
1729         }
1730
1731         s->s_flags |= MS_ACTIVE;
1732         mnt->mnt_sb = s;
1733         mnt->mnt_root = mntroot;
1734
1735         /* clone any lsm security options from the parent to the new sb */
1736         security_sb_clone_mnt_opts(data->sb, s);
1737
1738         dprintk("<-- nfs_xdev_get_sb() = 0\n");
1739         return 0;
1740
1741 out_err_nosb:
1742         nfs_free_server(server);
1743 out_err_noserver:
1744         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
1745         return error;
1746
1747 error_splat_super:
1748         up_write(&s->s_umount);
1749         deactivate_super(s);
1750         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
1751         return error;
1752 }
1753
1754 #ifdef CONFIG_NFS_V4
1755
1756 /*
1757  * Finish setting up a cloned NFS4 superblock
1758  */
1759 static void nfs4_clone_super(struct super_block *sb,
1760                             const struct super_block *old_sb)
1761 {
1762         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1763         sb->s_blocksize = old_sb->s_blocksize;
1764         sb->s_maxbytes = old_sb->s_maxbytes;
1765         sb->s_time_gran = 1;
1766         sb->s_op = old_sb->s_op;
1767         nfs_initialise_sb(sb);
1768 }
1769
1770 /*
1771  * Set up an NFS4 superblock
1772  */
1773 static void nfs4_fill_super(struct super_block *sb)
1774 {
1775         sb->s_time_gran = 1;
1776         sb->s_op = &nfs4_sops;
1777         nfs_initialise_sb(sb);
1778 }
1779
1780 /*
1781  * Validate NFSv4 mount options
1782  */
1783 static int nfs4_validate_mount_data(void *options,
1784                                     struct nfs_parsed_mount_data *args,
1785                                     const char *dev_name)
1786 {
1787         struct sockaddr_in *ap;
1788         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
1789         char *c;
1790
1791         memset(args, 0, sizeof(*args));
1792
1793         if (data == NULL)
1794                 goto out_no_data;
1795
1796         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1797         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1798         args->timeo             = 600;
1799         args->retrans           = 2;
1800         args->acregmin          = 3;
1801         args->acregmax          = 60;
1802         args->acdirmin          = 30;
1803         args->acdirmax          = 60;
1804         args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
1805         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1806
1807         switch (data->version) {
1808         case 1:
1809                 ap = (struct sockaddr_in *)&args->nfs_server.address;
1810                 if (data->host_addrlen > sizeof(args->nfs_server.address))
1811                         goto out_no_address;
1812                 if (data->host_addrlen == 0)
1813                         goto out_no_address;
1814                 args->nfs_server.addrlen = data->host_addrlen;
1815                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
1816                         return -EFAULT;
1817                 if (!nfs_verify_server_address((struct sockaddr *)
1818                                                 &args->nfs_server.address))
1819                         goto out_no_address;
1820
1821                 switch (data->auth_flavourlen) {
1822                 case 0:
1823                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1824                         break;
1825                 case 1:
1826                         if (copy_from_user(&args->auth_flavors[0],
1827                                            data->auth_flavours,
1828                                            sizeof(args->auth_flavors[0])))
1829                                 return -EFAULT;
1830                         break;
1831                 default:
1832                         goto out_inval_auth;
1833                 }
1834
1835                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1836                 if (IS_ERR(c))
1837                         return PTR_ERR(c);
1838                 args->nfs_server.hostname = c;
1839
1840                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1841                 if (IS_ERR(c))
1842                         return PTR_ERR(c);
1843                 args->nfs_server.export_path = c;
1844                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1845
1846                 c = strndup_user(data->client_addr.data, 16);
1847                 if (IS_ERR(c))
1848                         return PTR_ERR(c);
1849                 args->client_address = c;
1850
1851                 /*
1852                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
1853                  * can deal with.
1854                  */
1855
1856                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
1857                 args->rsize     = data->rsize;
1858                 args->wsize     = data->wsize;
1859                 args->timeo     = data->timeo;
1860                 args->retrans   = data->retrans;
1861                 args->acregmin  = data->acregmin;
1862                 args->acregmax  = data->acregmax;
1863                 args->acdirmin  = data->acdirmin;
1864                 args->acdirmax  = data->acdirmax;
1865                 args->nfs_server.protocol = data->proto;
1866
1867                 break;
1868         default: {
1869                 unsigned int len;
1870
1871                 if (nfs_parse_mount_options((char *)options, args) == 0)
1872                         return -EINVAL;
1873
1874                 if (!nfs_verify_server_address((struct sockaddr *)
1875                                                 &args->nfs_server.address))
1876                         return -EINVAL;
1877
1878                 switch (args->auth_flavor_len) {
1879                 case 0:
1880                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1881                         break;
1882                 case 1:
1883                         break;
1884                 default:
1885                         goto out_inval_auth;
1886                 }
1887
1888                 /*
1889                  * Split "dev_name" into "hostname:mntpath".
1890                  */
1891                 c = strchr(dev_name, ':');
1892                 if (c == NULL)
1893                         return -EINVAL;
1894                 /* while calculating len, pretend ':' is '\0' */
1895                 len = c - dev_name;
1896                 if (len > NFS4_MAXNAMLEN)
1897                         return -ENAMETOOLONG;
1898                 /* N.B. caller will free nfs_server.hostname in all cases */
1899                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1900                 if (!args->nfs_server.hostname)
1901                         goto out_nomem;
1902
1903                 c++;                    /* step over the ':' */
1904                 len = strlen(c);
1905                 if (len > NFS4_MAXPATHLEN)
1906                         return -ENAMETOOLONG;
1907                 args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
1908                 if (!args->nfs_server.export_path)
1909                         goto out_nomem;
1910
1911                 dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);
1912
1913                 if (args->client_address == NULL)
1914                         goto out_no_client_address;
1915
1916                 break;
1917                 }
1918         }
1919
1920         return 0;
1921
1922 out_no_data:
1923         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
1924         return -EINVAL;
1925
1926 out_inval_auth:
1927         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
1928                  data->auth_flavourlen);
1929         return -EINVAL;
1930
1931 out_nomem:
1932         dfprintk(MOUNT, "NFS4: not enough memory to handle mount options\n");
1933         return -ENOMEM;
1934
1935 out_no_address:
1936         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
1937         return -EINVAL;
1938
1939 out_no_client_address:
1940         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
1941         return -EINVAL;
1942 }
1943
1944 /*
1945  * Get the superblock for an NFS4 mountpoint
1946  */
1947 static int nfs4_get_sb(struct file_system_type *fs_type,
1948         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1949 {
1950         struct nfs_parsed_mount_data data;
1951         struct super_block *s;
1952         struct nfs_server *server;
1953         struct nfs_fh mntfh;
1954         struct dentry *mntroot;
1955         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1956         struct nfs_sb_mountdata sb_mntdata = {
1957                 .mntflags = flags,
1958         };
1959         int error;
1960
1961         security_init_mnt_opts(&data.lsm_opts);
1962
1963         /* Validate the mount data */
1964         error = nfs4_validate_mount_data(raw_data, &data, dev_name);
1965         if (error < 0)
1966                 goto out;
1967
1968         /* Get a volume representation */
1969         server = nfs4_create_server(&data, &mntfh);
1970         if (IS_ERR(server)) {
1971                 error = PTR_ERR(server);
1972                 goto out;
1973         }
1974         sb_mntdata.server = server;
1975
1976         if (server->flags & NFS4_MOUNT_UNSHARED)
1977                 compare_super = NULL;
1978
1979         /* Get a superblock - note that we may end up sharing one that already exists */
1980         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1981         if (IS_ERR(s)) {
1982                 error = PTR_ERR(s);
1983                 goto out_free;
1984         }
1985
1986         if (s->s_fs_info != server) {
1987                 nfs_free_server(server);
1988                 server = NULL;
1989         }
1990
1991         if (!s->s_root) {
1992                 /* initial superblock/root creation */
1993                 nfs4_fill_super(s);
1994         }
1995
1996         mntroot = nfs4_get_root(s, &mntfh);
1997         if (IS_ERR(mntroot)) {
1998                 error = PTR_ERR(mntroot);
1999                 goto error_splat_super;
2000         }
2001
2002         s->s_flags |= MS_ACTIVE;
2003         mnt->mnt_sb = s;
2004         mnt->mnt_root = mntroot;
2005         error = 0;
2006
2007 out:
2008         kfree(data.client_address);
2009         kfree(data.nfs_server.export_path);
2010         kfree(data.nfs_server.hostname);
2011         security_free_mnt_opts(&data.lsm_opts);
2012         return error;
2013
2014 out_free:
2015         nfs_free_server(server);
2016         goto out;
2017
2018 error_splat_super:
2019         up_write(&s->s_umount);
2020         deactivate_super(s);
2021         goto out;
2022 }
2023
2024 static void nfs4_kill_super(struct super_block *sb)
2025 {
2026         struct nfs_server *server = NFS_SB(sb);
2027
2028         nfs_return_all_delegations(sb);
2029         kill_anon_super(sb);
2030
2031         nfs4_renewd_prepare_shutdown(server);
2032         nfs_free_server(server);
2033 }
2034
2035 /*
2036  * Clone an NFS4 server record on xdev traversal (FSID-change)
2037  */
2038 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2039                             const char *dev_name, void *raw_data,
2040                             struct vfsmount *mnt)
2041 {
2042         struct nfs_clone_mount *data = raw_data;
2043         struct super_block *s;
2044         struct nfs_server *server;
2045         struct dentry *mntroot;
2046         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2047         struct nfs_sb_mountdata sb_mntdata = {
2048                 .mntflags = flags,
2049         };
2050         int error;
2051
2052         dprintk("--> nfs4_xdev_get_sb()\n");
2053
2054         /* create a new volume representation */
2055         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2056         if (IS_ERR(server)) {
2057                 error = PTR_ERR(server);
2058                 goto out_err_noserver;
2059         }
2060         sb_mntdata.server = server;
2061
2062         if (server->flags & NFS4_MOUNT_UNSHARED)
2063                 compare_super = NULL;
2064
2065         /* Get a superblock - note that we may end up sharing one that already exists */
2066         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2067         if (IS_ERR(s)) {
2068                 error = PTR_ERR(s);
2069                 goto out_err_nosb;
2070         }
2071
2072         if (s->s_fs_info != server) {
2073                 nfs_free_server(server);
2074                 server = NULL;
2075         }
2076
2077         if (!s->s_root) {
2078                 /* initial superblock/root creation */
2079                 nfs4_clone_super(s, data->sb);
2080         }
2081
2082         mntroot = nfs4_get_root(s, data->fh);
2083         if (IS_ERR(mntroot)) {
2084                 error = PTR_ERR(mntroot);
2085                 goto error_splat_super;
2086         }
2087         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2088                 dput(mntroot);
2089                 error = -ESTALE;
2090                 goto error_splat_super;
2091         }
2092
2093         s->s_flags |= MS_ACTIVE;
2094         mnt->mnt_sb = s;
2095         mnt->mnt_root = mntroot;
2096
2097         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2098         return 0;
2099
2100 out_err_nosb:
2101         nfs_free_server(server);
2102 out_err_noserver:
2103         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2104         return error;
2105
2106 error_splat_super:
2107         up_write(&s->s_umount);
2108         deactivate_super(s);
2109         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2110         return error;
2111 }
2112
2113 /*
2114  * Create an NFS4 server record on referral traversal
2115  */
2116 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2117                                 const char *dev_name, void *raw_data,
2118                                 struct vfsmount *mnt)
2119 {
2120         struct nfs_clone_mount *data = raw_data;
2121         struct super_block *s;
2122         struct nfs_server *server;
2123         struct dentry *mntroot;
2124         struct nfs_fh mntfh;
2125         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2126         struct nfs_sb_mountdata sb_mntdata = {
2127                 .mntflags = flags,
2128         };
2129         int error;
2130
2131         dprintk("--> nfs4_referral_get_sb()\n");
2132
2133         /* create a new volume representation */
2134         server = nfs4_create_referral_server(data, &mntfh);
2135         if (IS_ERR(server)) {
2136                 error = PTR_ERR(server);
2137                 goto out_err_noserver;
2138         }
2139         sb_mntdata.server = server;
2140
2141         if (server->flags & NFS4_MOUNT_UNSHARED)
2142                 compare_super = NULL;
2143
2144         /* Get a superblock - note that we may end up sharing one that already exists */
2145         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2146         if (IS_ERR(s)) {
2147                 error = PTR_ERR(s);
2148                 goto out_err_nosb;
2149         }
2150
2151         if (s->s_fs_info != server) {
2152                 nfs_free_server(server);
2153                 server = NULL;
2154         }
2155
2156         if (!s->s_root) {
2157                 /* initial superblock/root creation */
2158                 nfs4_fill_super(s);
2159         }
2160
2161         mntroot = nfs4_get_root(s, &mntfh);
2162         if (IS_ERR(mntroot)) {
2163                 error = PTR_ERR(mntroot);
2164                 goto error_splat_super;
2165         }
2166         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2167                 dput(mntroot);
2168                 error = -ESTALE;
2169                 goto error_splat_super;
2170         }
2171
2172         s->s_flags |= MS_ACTIVE;
2173         mnt->mnt_sb = s;
2174         mnt->mnt_root = mntroot;
2175
2176         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2177         return 0;
2178
2179 out_err_nosb:
2180         nfs_free_server(server);
2181 out_err_noserver:
2182         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2183         return error;
2184
2185 error_splat_super:
2186         up_write(&s->s_umount);
2187         deactivate_super(s);
2188         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2189         return error;
2190 }
2191
2192 #endif /* CONFIG_NFS_V4 */