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   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_err, NULL }
 194 };
 195
 196
 197 static void nfs_umount_begin(struct vfsmount *, int);
 198 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 199 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 200 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 201 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 202 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 203                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 204 static void nfs_kill_super(struct super_block *);
 205 static void nfs_put_super(struct super_block *);
 206
 207 static struct file_system_type nfs_fs_type = {
 208         .owner          = THIS_MODULE,
 209         .name           = "nfs",
 210         .get_sb         = nfs_get_sb,
 211         .kill_sb        = nfs_kill_super,
 212         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 213 };
 214
 215 struct file_system_type nfs_xdev_fs_type = {
 216         .owner          = THIS_MODULE,
 217         .name           = "nfs",
 218         .get_sb         = nfs_xdev_get_sb,
 219         .kill_sb        = nfs_kill_super,
 220         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 221 };
 222
 223 static const struct super_operations nfs_sops = {
 224         .alloc_inode    = nfs_alloc_inode,
 225         .destroy_inode  = nfs_destroy_inode,
 226         .write_inode    = nfs_write_inode,
 227         .put_super      = nfs_put_super,
 228         .statfs         = nfs_statfs,
 229         .clear_inode    = nfs_clear_inode,
 230         .umount_begin   = nfs_umount_begin,
 231         .show_options   = nfs_show_options,
 232         .show_stats     = nfs_show_stats,
 233 };
 234
 235 #ifdef CONFIG_NFS_V4
 236 static int nfs4_get_sb(struct file_system_type *fs_type,
 237         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 238 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 239         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 240 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 241         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 242 static void nfs4_kill_super(struct super_block *sb);
 243
 244 static struct file_system_type nfs4_fs_type = {
 245         .owner          = THIS_MODULE,
 246         .name           = "nfs4",
 247         .get_sb         = nfs4_get_sb,
 248         .kill_sb        = nfs4_kill_super,
 249         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 250 };
 251
 252 struct file_system_type nfs4_xdev_fs_type = {
 253         .owner          = THIS_MODULE,
 254         .name           = "nfs4",
 255         .get_sb         = nfs4_xdev_get_sb,
 256         .kill_sb        = nfs4_kill_super,
 257         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 258 };
 259
 260 struct file_system_type nfs4_referral_fs_type = {
 261         .owner          = THIS_MODULE,
 262         .name           = "nfs4",
 263         .get_sb         = nfs4_referral_get_sb,
 264         .kill_sb        = nfs4_kill_super,
 265         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 266 };
 267
 268 static const struct super_operations nfs4_sops = {
 269         .alloc_inode    = nfs_alloc_inode,
 270         .destroy_inode  = nfs_destroy_inode,
 271         .write_inode    = nfs_write_inode,
 272         .statfs         = nfs_statfs,
 273         .clear_inode    = nfs4_clear_inode,
 274         .umount_begin   = nfs_umount_begin,
 275         .show_options   = nfs_show_options,
 276         .show_stats     = nfs_show_stats,
 277 };
 278 #endif
 279
 280 static struct shrinker acl_shrinker = {
 281         .shrink         = nfs_access_cache_shrinker,
 282         .seeks          = DEFAULT_SEEKS,
 283 };
 284
 285 /*
 286  * Register the NFS filesystems
 287  */
 288 int __init register_nfs_fs(void)
 289 {
 290         int ret;
 291
 292         ret = register_filesystem(&nfs_fs_type);
 293         if (ret < 0)
 294                 goto error_0;
 295
 296         ret = nfs_register_sysctl();
 297         if (ret < 0)
 298                 goto error_1;
 299 #ifdef CONFIG_NFS_V4
 300         ret = register_filesystem(&nfs4_fs_type);
 301         if (ret < 0)
 302                 goto error_2;
 303 #endif
 304         register_shrinker(&acl_shrinker);
 305         return 0;
 306
 307 #ifdef CONFIG_NFS_V4
 308 error_2:
 309         nfs_unregister_sysctl();
 310 #endif
 311 error_1:
 312         unregister_filesystem(&nfs_fs_type);
 313 error_0:
 314         return ret;
 315 }
 316
 317 /*
 318  * Unregister the NFS filesystems
 319  */
 320 void __exit unregister_nfs_fs(void)
 321 {
 322         unregister_shrinker(&acl_shrinker);
 323 #ifdef CONFIG_NFS_V4
 324         unregister_filesystem(&nfs4_fs_type);
 325 #endif
 326         nfs_unregister_sysctl();
 327         unregister_filesystem(&nfs_fs_type);
 328 }
 329
 330 void nfs_sb_active(struct nfs_server *server)
 331 {
 332         atomic_inc(&server->active);
 333 }
 334
 335 void nfs_sb_deactive(struct nfs_server *server)
 336 {
 337         if (atomic_dec_and_test(&server->active))
 338                 wake_up(&server->active_wq);
 339 }
 340
 341 static void nfs_put_super(struct super_block *sb)
 342 {
 343         struct nfs_server *server = NFS_SB(sb);
 344         /*
 345          * Make sure there are no outstanding ops to this server.
 346          * If so, wait for them to finish before allowing the
 347          * unmount to continue.
 348          */
 349         wait_event(server->active_wq, atomic_read(&server->active) == 0);
 350 }
 351
 352 /*
 353  * Deliver file system statistics to userspace
 354  */
 355 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 356 {
 357         struct nfs_server *server = NFS_SB(dentry->d_sb);
 358         unsigned char blockbits;
 359         unsigned long blockres;
 360         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 361         struct nfs_fattr fattr;
 362         struct nfs_fsstat res = {
 363                         .fattr = &fattr,
 364         };
 365         int error;
 366
 367         lock_kernel();
 368
 369         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 370         if (error < 0)
 371                 goto out_err;
 372         buf->f_type = NFS_SUPER_MAGIC;
 373
 374         /*
 375          * Current versions of glibc do not correctly handle the
 376          * case where f_frsize != f_bsize.  Eventually we want to
 377          * report the value of wtmult in this field.
 378          */
 379         buf->f_frsize = dentry->d_sb->s_blocksize;
 380
 381         /*
 382          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 383          * are reported in units of f_frsize.  Linux hasn't had
 384          * an f_frsize field in its statfs struct until recently,
 385          * thus historically Linux's sys_statfs reports these
 386          * fields in units of f_bsize.
 387          */
 388         buf->f_bsize = dentry->d_sb->s_blocksize;
 389         blockbits = dentry->d_sb->s_blocksize_bits;
 390         blockres = (1 << blockbits) - 1;
 391         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 392         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 393         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 394
 395         buf->f_files = res.tfiles;
 396         buf->f_ffree = res.afiles;
 397
 398         buf->f_namelen = server->namelen;
 399
 400         unlock_kernel();
 401         return 0;
 402
 403  out_err:
 404         dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
 405         unlock_kernel();
 406         return error;
 407 }
 408
 409 /*
 410  * Map the security flavour number to a name
 411  */
 412 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 413 {
 414         static const struct {
 415                 rpc_authflavor_t flavour;
 416                 const char *str;
 417         } sec_flavours[] = {
 418                 { RPC_AUTH_NULL, "null" },
 419                 { RPC_AUTH_UNIX, "sys" },
 420                 { RPC_AUTH_GSS_KRB5, "krb5" },
 421                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 422                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 423                 { RPC_AUTH_GSS_LKEY, "lkey" },
 424                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 425                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 426                 { RPC_AUTH_GSS_SPKM, "spkm" },
 427                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 428                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 429                 { UINT_MAX, "unknown" }
 430         };
 431         int i;
 432
 433         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 434                 if (sec_flavours[i].flavour == flavour)
 435                         break;
 436         }
 437         return sec_flavours[i].str;
 438 }
 439
 440 /*
 441  * Describe the mount options in force on this server representation
 442  */
 443 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
 444 {
 445         static const struct proc_nfs_info {
 446                 int flag;
 447                 const char *str;
 448                 const char *nostr;
 449         } nfs_info[] = {
 450                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 451                 { NFS_MOUNT_INTR, ",intr", ",nointr" },
 452                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 453                 { NFS_MOUNT_NOAC, ",noac", "" },
 454                 { NFS_MOUNT_NONLM, ",nolock", "" },
 455                 { NFS_MOUNT_NOACL, ",noacl", "" },
 456                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 457                 { NFS_MOUNT_UNSHARED, ",nosharecache", ""},
 458                 { 0, NULL, NULL }
 459         };
 460         const struct proc_nfs_info *nfs_infop;
 461         struct nfs_client *clp = nfss->nfs_client;
 462
 463         seq_printf(m, ",vers=%d", clp->rpc_ops->version);
 464         seq_printf(m, ",rsize=%d", nfss->rsize);
 465         seq_printf(m, ",wsize=%d", nfss->wsize);
 466         if (nfss->acregmin != 3*HZ || showdefaults)
 467                 seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
 468         if (nfss->acregmax != 60*HZ || showdefaults)
 469                 seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
 470         if (nfss->acdirmin != 30*HZ || showdefaults)
 471                 seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
 472         if (nfss->acdirmax != 60*HZ || showdefaults)
 473                 seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
 474         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 475                 if (nfss->flags & nfs_infop->flag)
 476                         seq_puts(m, nfs_infop->str);
 477                 else
 478                         seq_puts(m, nfs_infop->nostr);
 479         }
 480         seq_printf(m, ",proto=%s",
 481                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 482         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 483         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 484         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 485 }
 486
 487 /*
 488  * Describe the mount options on this VFS mountpoint
 489  */
 490 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 491 {
 492         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 493
 494         nfs_show_mount_options(m, nfss, 0);
 495
 496         seq_printf(m, ",addr=%s",
 497                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 498                                                         RPC_DISPLAY_ADDR));
 499
 500         return 0;
 501 }
 502
 503 /*
 504  * Present statistical information for this VFS mountpoint
 505  */
 506 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 507 {
 508         int i, cpu;
 509         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 510         struct rpc_auth *auth = nfss->client->cl_auth;
 511         struct nfs_iostats totals = { };
 512
 513         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 514
 515         /*
 516          * Display all mount option settings
 517          */
 518         seq_printf(m, "\n\topts:\t");
 519         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 520         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 521         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 522         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 523         nfs_show_mount_options(m, nfss, 1);
 524
 525         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 526
 527         seq_printf(m, "\n\tcaps:\t");
 528         seq_printf(m, "caps=0x%x", nfss->caps);
 529         seq_printf(m, ",wtmult=%d", nfss->wtmult);
 530         seq_printf(m, ",dtsize=%d", nfss->dtsize);
 531         seq_printf(m, ",bsize=%d", nfss->bsize);
 532         seq_printf(m, ",namelen=%d", nfss->namelen);
 533
 534 #ifdef CONFIG_NFS_V4
 535         if (nfss->nfs_client->rpc_ops->version == 4) {
 536                 seq_printf(m, "\n\tnfsv4:\t");
 537                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 538                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 539                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 540         }
 541 #endif
 542
 543         /*
 544          * Display security flavor in effect for this mount
 545          */
 546         seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
 547         if (auth->au_flavor)
 548                 seq_printf(m, ",pseudoflavor=%d", auth->au_flavor);
 549
 550         /*
 551          * Display superblock I/O counters
 552          */
 553         for_each_possible_cpu(cpu) {
 554                 struct nfs_iostats *stats;
 555
 556                 preempt_disable();
 557                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 558
 559                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 560                         totals.events[i] += stats->events[i];
 561                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 562                         totals.bytes[i] += stats->bytes[i];
 563
 564                 preempt_enable();
 565         }
 566
 567         seq_printf(m, "\n\tevents:\t");
 568         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 569                 seq_printf(m, "%lu ", totals.events[i]);
 570         seq_printf(m, "\n\tbytes:\t");
 571         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 572                 seq_printf(m, "%Lu ", totals.bytes[i]);
 573         seq_printf(m, "\n");
 574
 575         rpc_print_iostats(m, nfss->client);
 576
 577         return 0;
 578 }
 579
 580 /*
 581  * Begin unmount by attempting to remove all automounted mountpoints we added
 582  * in response to xdev traversals and referrals
 583  */
 584 static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
 585 {
 586         struct nfs_server *server = NFS_SB(vfsmnt->mnt_sb);
 587         struct rpc_clnt *rpc;
 588
 589         shrink_submounts(vfsmnt, &nfs_automount_list);
 590
 591         if (!(flags & MNT_FORCE))
 592                 return;
 593         /* -EIO all pending I/O */
 594         rpc = server->client_acl;
 595         if (!IS_ERR(rpc))
 596                 rpc_killall_tasks(rpc);
 597         rpc = server->client;
 598         if (!IS_ERR(rpc))
 599                 rpc_killall_tasks(rpc);
 600 }
 601
 602 /*
 603  * Set the port number in an address.  Be agnostic about the address family.
 604  */
 605 static void nfs_set_port(struct sockaddr *sap, unsigned short port)
 606 {
 607         switch (sap->sa_family) {
 608         case AF_INET: {
 609                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 610                 ap->sin_port = htons(port);
 611                 break;
 612         }
 613         case AF_INET6: {
 614                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 615                 ap->sin6_port = htons(port);
 616                 break;
 617         }
 618         }
 619 }
 620
 621 /*
 622  * Sanity-check a server address provided by the mount command.
 623  *
 624  * Address family must be initialized, and address must not be
 625  * the ANY address for that family.
 626  */
 627 static int nfs_verify_server_address(struct sockaddr *addr)
 628 {
 629         switch (addr->sa_family) {
 630         case AF_INET: {
 631                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 632                 return sa->sin_addr.s_addr != INADDR_ANY;
 633         }
 634         case AF_INET6: {
 635                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 636                 return !ipv6_addr_any(sa);
 637         }
 638         }
 639
 640         return 0;
 641 }
 642
 643 /*
 644  * Parse string addresses passed in via a mount option,
 645  * and construct a sockaddr based on the result.
 646  *
 647  * If address parsing fails, set the sockaddr's address
 648  * family to AF_UNSPEC to force nfs_verify_server_address()
 649  * to punt the mount.
 650  */
 651 static void nfs_parse_server_address(char *value,
 652                                      struct sockaddr *sap,
 653                                      size_t *len)
 654 {
 655         if (strchr(value, ':')) {
 656                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 657                 u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
 658
 659                 ap->sin6_family = AF_INET6;
 660                 *len = sizeof(*ap);
 661                 if (in6_pton(value, -1, addr, '\0', NULL))
 662                         return;
 663         } else {
 664                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 665                 u8 *addr = (u8 *)&ap->sin_addr.s_addr;
 666
 667                 ap->sin_family = AF_INET;
 668                 *len = sizeof(*ap);
 669                 if (in4_pton(value, -1, addr, '\0', NULL))
 670                         return;
 671         }
 672
 673         sap->sa_family = AF_UNSPEC;
 674         *len = 0;
 675 }
 676
 677 /*
 678  * Error-check and convert a string of mount options from user space into
 679  * a data structure
 680  */
 681 static int nfs_parse_mount_options(char *raw,
 682                                    struct nfs_parsed_mount_data *mnt)
 683 {
 684         char *p, *string;
 685         unsigned short port = 0;
 686
 687         if (!raw) {
 688                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 689                 return 1;
 690         }
 691         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 692
 693         while ((p = strsep(&raw, ",")) != NULL) {
 694                 substring_t args[MAX_OPT_ARGS];
 695                 int option, token;
 696
 697                 if (!*p)
 698                         continue;
 699
 700                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 701
 702                 token = match_token(p, nfs_mount_option_tokens, args);
 703                 switch (token) {
 704                 case Opt_soft:
 705                         mnt->flags |= NFS_MOUNT_SOFT;
 706                         break;
 707                 case Opt_hard:
 708                         mnt->flags &= ~NFS_MOUNT_SOFT;
 709                         break;
 710                 case Opt_intr:
 711                         mnt->flags |= NFS_MOUNT_INTR;
 712                         break;
 713                 case Opt_nointr:
 714                         mnt->flags &= ~NFS_MOUNT_INTR;
 715                         break;
 716                 case Opt_posix:
 717                         mnt->flags |= NFS_MOUNT_POSIX;
 718                         break;
 719                 case Opt_noposix:
 720                         mnt->flags &= ~NFS_MOUNT_POSIX;
 721                         break;
 722                 case Opt_cto:
 723                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 724                         break;
 725                 case Opt_nocto:
 726                         mnt->flags |= NFS_MOUNT_NOCTO;
 727                         break;
 728                 case Opt_ac:
 729                         mnt->flags &= ~NFS_MOUNT_NOAC;
 730                         break;
 731                 case Opt_noac:
 732                         mnt->flags |= NFS_MOUNT_NOAC;
 733                         break;
 734                 case Opt_lock:
 735                         mnt->flags &= ~NFS_MOUNT_NONLM;
 736                         break;
 737                 case Opt_nolock:
 738                         mnt->flags |= NFS_MOUNT_NONLM;
 739                         break;
 740                 case Opt_v2:
 741                         mnt->flags &= ~NFS_MOUNT_VER3;
 742                         break;
 743                 case Opt_v3:
 744                         mnt->flags |= NFS_MOUNT_VER3;
 745                         break;
 746                 case Opt_udp:
 747                         mnt->flags &= ~NFS_MOUNT_TCP;
 748                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 749                         mnt->timeo = 7;
 750                         mnt->retrans = 5;
 751                         break;
 752                 case Opt_tcp:
 753                         mnt->flags |= NFS_MOUNT_TCP;
 754                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 755                         mnt->timeo = 600;
 756                         mnt->retrans = 2;
 757                         break;
 758                 case Opt_rdma:
 759                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 760                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 761                         mnt->timeo = 600;
 762                         mnt->retrans = 2;
 763                         break;
 764                 case Opt_acl:
 765                         mnt->flags &= ~NFS_MOUNT_NOACL;
 766                         break;
 767                 case Opt_noacl:
 768                         mnt->flags |= NFS_MOUNT_NOACL;
 769                         break;
 770                 case Opt_rdirplus:
 771                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 772                         break;
 773                 case Opt_nordirplus:
 774                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 775                         break;
 776                 case Opt_sharecache:
 777                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 778                         break;
 779                 case Opt_nosharecache:
 780                         mnt->flags |= NFS_MOUNT_UNSHARED;
 781                         break;
 782
 783                 case Opt_port:
 784                         if (match_int(args, &option))
 785                                 return 0;
 786                         if (option < 0 || option > 65535)
 787                                 return 0;
 788                         port = option;
 789                         break;
 790                 case Opt_rsize:
 791                         if (match_int(args, &mnt->rsize))
 792                                 return 0;
 793                         break;
 794                 case Opt_wsize:
 795                         if (match_int(args, &mnt->wsize))
 796                                 return 0;
 797                         break;
 798                 case Opt_bsize:
 799                         if (match_int(args, &option))
 800                                 return 0;
 801                         if (option < 0)
 802                                 return 0;
 803                         mnt->bsize = option;
 804                         break;
 805                 case Opt_timeo:
 806                         if (match_int(args, &mnt->timeo))
 807                                 return 0;
 808                         break;
 809                 case Opt_retrans:
 810                         if (match_int(args, &mnt->retrans))
 811                                 return 0;
 812                         break;
 813                 case Opt_acregmin:
 814                         if (match_int(args, &mnt->acregmin))
 815                                 return 0;
 816                         break;
 817                 case Opt_acregmax:
 818                         if (match_int(args, &mnt->acregmax))
 819                                 return 0;
 820                         break;
 821                 case Opt_acdirmin:
 822                         if (match_int(args, &mnt->acdirmin))
 823                                 return 0;
 824                         break;
 825                 case Opt_acdirmax:
 826                         if (match_int(args, &mnt->acdirmax))
 827                                 return 0;
 828                         break;
 829                 case Opt_actimeo:
 830                         if (match_int(args, &option))
 831                                 return 0;
 832                         if (option < 0)
 833                                 return 0;
 834                         mnt->acregmin =
 835                         mnt->acregmax =
 836                         mnt->acdirmin =
 837                         mnt->acdirmax = option;
 838                         break;
 839                 case Opt_namelen:
 840                         if (match_int(args, &mnt->namlen))
 841                                 return 0;
 842                         break;
 843                 case Opt_mountport:
 844                         if (match_int(args, &option))
 845                                 return 0;
 846                         if (option < 0 || option > 65535)
 847                                 return 0;
 848                         mnt->mount_server.port = option;
 849                         break;
 850                 case Opt_mountvers:
 851                         if (match_int(args, &option))
 852                                 return 0;
 853                         if (option < 0)
 854                                 return 0;
 855                         mnt->mount_server.version = option;
 856                         break;
 857                 case Opt_nfsvers:
 858                         if (match_int(args, &option))
 859                                 return 0;
 860                         switch (option) {
 861                         case 2:
 862                                 mnt->flags &= ~NFS_MOUNT_VER3;
 863                                 break;
 864                         case 3:
 865                                 mnt->flags |= NFS_MOUNT_VER3;
 866                                 break;
 867                         default:
 868                                 goto out_unrec_vers;
 869                         }
 870                         break;
 871
 872                 case Opt_sec:
 873                         string = match_strdup(args);
 874                         if (string == NULL)
 875                                 goto out_nomem;
 876                         token = match_token(string, nfs_secflavor_tokens, args);
 877                         kfree(string);
 878
 879                         /*
 880                          * The flags setting is for v2/v3.  The flavor_len
 881                          * setting is for v4.  v2/v3 also need to know the
 882                          * difference between NULL and UNIX.
 883                          */
 884                         switch (token) {
 885                         case Opt_sec_none:
 886                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 887                                 mnt->auth_flavor_len = 0;
 888                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 889                                 break;
 890                         case Opt_sec_sys:
 891                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 892                                 mnt->auth_flavor_len = 0;
 893                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 894                                 break;
 895                         case Opt_sec_krb5:
 896                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 897                                 mnt->auth_flavor_len = 1;
 898                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 899                                 break;
 900                         case Opt_sec_krb5i:
 901                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 902                                 mnt->auth_flavor_len = 1;
 903                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 904                                 break;
 905                         case Opt_sec_krb5p:
 906                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 907                                 mnt->auth_flavor_len = 1;
 908                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 909                                 break;
 910                         case Opt_sec_lkey:
 911                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 912                                 mnt->auth_flavor_len = 1;
 913                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 914                                 break;
 915                         case Opt_sec_lkeyi:
 916                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 917                                 mnt->auth_flavor_len = 1;
 918                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 919                                 break;
 920                         case Opt_sec_lkeyp:
 921                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 922                                 mnt->auth_flavor_len = 1;
 923                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 924                                 break;
 925                         case Opt_sec_spkm:
 926                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 927                                 mnt->auth_flavor_len = 1;
 928                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
 929                                 break;
 930                         case Opt_sec_spkmi:
 931                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 932                                 mnt->auth_flavor_len = 1;
 933                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
 934                                 break;
 935                         case Opt_sec_spkmp:
 936                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 937                                 mnt->auth_flavor_len = 1;
 938                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
 939                                 break;
 940                         default:
 941                                 goto out_unrec_sec;
 942                         }
 943                         break;
 944                 case Opt_proto:
 945                         string = match_strdup(args);
 946                         if (string == NULL)
 947                                 goto out_nomem;
 948                         token = match_token(string,
 949                                             nfs_xprt_protocol_tokens, args);
 950                         kfree(string);
 951
 952                         switch (token) {
 953                         case Opt_xprt_udp:
 954                                 mnt->flags &= ~NFS_MOUNT_TCP;
 955                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 956                                 mnt->timeo = 7;
 957                                 mnt->retrans = 5;
 958                                 break;
 959                         case Opt_xprt_tcp:
 960                                 mnt->flags |= NFS_MOUNT_TCP;
 961                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 962                                 mnt->timeo = 600;
 963                                 mnt->retrans = 2;
 964                                 break;
 965                         case Opt_xprt_rdma:
 966                                 /* vector side protocols to TCP */
 967                                 mnt->flags |= NFS_MOUNT_TCP;
 968                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 969                                 mnt->timeo = 600;
 970                                 mnt->retrans = 2;
 971                                 break;
 972                         default:
 973                                 goto out_unrec_xprt;
 974                         }
 975                         break;
 976                 case Opt_mountproto:
 977                         string = match_strdup(args);
 978                         if (string == NULL)
 979                                 goto out_nomem;
 980                         token = match_token(string,
 981                                             nfs_xprt_protocol_tokens, args);
 982                         kfree(string);
 983
 984                         switch (token) {
 985                         case Opt_xprt_udp:
 986                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 987                                 break;
 988                         case Opt_xprt_tcp:
 989                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 990                                 break;
 991                         case Opt_xprt_rdma: /* not used for side protocols */
 992                         default:
 993                                 goto out_unrec_xprt;
 994                         }
 995                         break;
 996                 case Opt_addr:
 997                         string = match_strdup(args);
 998                         if (string == NULL)
 999                                 goto out_nomem;
1000                         nfs_parse_server_address(string, (struct sockaddr *)
1001                                                  &mnt->nfs_server.address,
1002                                                  &mnt->nfs_server.addrlen);
1003                         kfree(string);
1004                         break;
1005                 case Opt_clientaddr:
1006                         string = match_strdup(args);
1007                         if (string == NULL)
1008                                 goto out_nomem;
1009                         kfree(mnt->client_address);
1010                         mnt->client_address = string;
1011                         break;
1012                 case Opt_mounthost:
1013                         string = match_strdup(args);
1014                         if (string == NULL)
1015                                 goto out_nomem;
1016                         kfree(mnt->mount_server.hostname);
1017                         mnt->mount_server.hostname = string;
1018                         break;
1019                 case Opt_mountaddr:
1020                         string = match_strdup(args);
1021                         if (string == NULL)
1022                                 goto out_nomem;
1023                         nfs_parse_server_address(string, (struct sockaddr *)
1024                                                  &mnt->mount_server.address,
1025                                                  &mnt->mount_server.addrlen);
1026                         kfree(string);
1027                         break;
1028
1029                 case Opt_userspace:
1030                 case Opt_deprecated:
1031                         break;
1032
1033                 default:
1034                         goto out_unknown;
1035                 }
1036         }
1037
1038         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address, port);
1039
1040         return 1;
1041
1042 out_nomem:
1043         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1044         return 0;
1045
1046 out_unrec_vers:
1047         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1048         return 0;
1049
1050 out_unrec_xprt:
1051         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1052         return 0;
1053
1054 out_unrec_sec:
1055         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1056         return 0;
1057
1058 out_unknown:
1059         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1060         return 0;
1061 }
1062
1063 /*
1064  * Use the remote server's MOUNT service to request the NFS file handle
1065  * corresponding to the provided path.
1066  */
1067 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1068                          struct nfs_fh *root_fh)
1069 {
1070         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1071         char *hostname;
1072         int status;
1073
1074         if (args->mount_server.version == 0) {
1075                 if (args->flags & NFS_MOUNT_VER3)
1076                         args->mount_server.version = NFS_MNT3_VERSION;
1077                 else
1078                         args->mount_server.version = NFS_MNT_VERSION;
1079         }
1080
1081         if (args->mount_server.hostname)
1082                 hostname = args->mount_server.hostname;
1083         else
1084                 hostname = args->nfs_server.hostname;
1085
1086         /*
1087          * Construct the mount server's address.
1088          */
1089         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1090                 memcpy(sap, &args->nfs_server.address,
1091                        args->nfs_server.addrlen);
1092                 args->mount_server.addrlen = args->nfs_server.addrlen;
1093         }
1094
1095         /*
1096          * autobind will be used if mount_server.port == 0
1097          */
1098         nfs_set_port(sap, args->mount_server.port);
1099
1100         /*
1101          * Now ask the mount server to map our export path
1102          * to a file handle.
1103          */
1104         status = nfs_mount(sap,
1105                            args->mount_server.addrlen,
1106                            hostname,
1107                            args->nfs_server.export_path,
1108                            args->mount_server.version,
1109                            args->mount_server.protocol,
1110                            root_fh);
1111         if (status == 0)
1112                 return 0;
1113
1114         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d",
1115                         hostname, status);
1116         return status;
1117 }
1118
1119 /*
1120  * Validate the NFS2/NFS3 mount data
1121  * - fills in the mount root filehandle
1122  *
1123  * For option strings, user space handles the following behaviors:
1124  *
1125  * + DNS: mapping server host name to IP address ("addr=" option)
1126  *
1127  * + failure mode: how to behave if a mount request can't be handled
1128  *   immediately ("fg/bg" option)
1129  *
1130  * + retry: how often to retry a mount request ("retry=" option)
1131  *
1132  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1133  *   mountproto=tcp after mountproto=udp, and so on
1134  */
1135 static int nfs_validate_mount_data(void *options,
1136                                    struct nfs_parsed_mount_data *args,
1137                                    struct nfs_fh *mntfh,
1138                                    const char *dev_name)
1139 {
1140         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1141
1142         memset(args, 0, sizeof(*args));
1143
1144         if (data == NULL)
1145                 goto out_no_data;
1146
1147         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1148         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1149         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1150         args->timeo             = 600;
1151         args->retrans           = 2;
1152         args->acregmin          = 3;
1153         args->acregmax          = 60;
1154         args->acdirmin          = 30;
1155         args->acdirmax          = 60;
1156         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1157         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1158
1159         switch (data->version) {
1160         case 1:
1161                 data->namlen = 0;
1162         case 2:
1163                 data->bsize = 0;
1164         case 3:
1165                 if (data->flags & NFS_MOUNT_VER3)
1166                         goto out_no_v3;
1167                 data->root.size = NFS2_FHSIZE;
1168                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1169         case 4:
1170                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1171                         goto out_no_sec;
1172         case 5:
1173                 memset(data->context, 0, sizeof(data->context));
1174         case 6:
1175                 if (data->flags & NFS_MOUNT_VER3)
1176                         mntfh->size = data->root.size;
1177                 else
1178                         mntfh->size = NFS2_FHSIZE;
1179
1180                 if (mntfh->size > sizeof(mntfh->data))
1181                         goto out_invalid_fh;
1182
1183                 memcpy(mntfh->data, data->root.data, mntfh->size);
1184                 if (mntfh->size < sizeof(mntfh->data))
1185                         memset(mntfh->data + mntfh->size, 0,
1186                                sizeof(mntfh->data) - mntfh->size);
1187
1188                 /*
1189                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1190                  * can deal with.
1191                  */
1192                 args->flags             = data->flags;
1193                 args->rsize             = data->rsize;
1194                 args->wsize             = data->wsize;
1195                 args->flags             = data->flags;
1196                 args->timeo             = data->timeo;
1197                 args->retrans           = data->retrans;
1198                 args->acregmin          = data->acregmin;
1199                 args->acregmax          = data->acregmax;
1200                 args->acdirmin          = data->acdirmin;
1201                 args->acdirmax          = data->acdirmax;
1202
1203                 memcpy(&args->nfs_server.address, &data->addr,
1204                        sizeof(data->addr));
1205                 args->nfs_server.addrlen = sizeof(data->addr);
1206                 if (!nfs_verify_server_address((struct sockaddr *)
1207                                                 &args->nfs_server.address))
1208                         goto out_no_address;
1209
1210                 if (!(data->flags & NFS_MOUNT_TCP))
1211                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1212                 /* N.B. caller will free nfs_server.hostname in all cases */
1213                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1214                 args->namlen            = data->namlen;
1215                 args->bsize             = data->bsize;
1216                 args->auth_flavors[0]   = data->pseudoflavor;
1217                 break;
1218         default: {
1219                 unsigned int len;
1220                 char *c;
1221                 int status;
1222
1223                 if (nfs_parse_mount_options((char *)options, args) == 0)
1224                         return -EINVAL;
1225
1226                 if (!nfs_verify_server_address((struct sockaddr *)
1227                                                 &args->nfs_server.address))
1228                         goto out_no_address;
1229
1230                 c = strchr(dev_name, ':');
1231                 if (c == NULL)
1232                         return -EINVAL;
1233                 len = c - dev_name;
1234                 /* N.B. caller will free nfs_server.hostname in all cases */
1235                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1236
1237                 c++;
1238                 if (strlen(c) > NFS_MAXPATHLEN)
1239                         return -ENAMETOOLONG;
1240                 args->nfs_server.export_path = c;
1241
1242                 status = nfs_try_mount(args, mntfh);
1243                 if (status)
1244                         return status;
1245
1246                 break;
1247                 }
1248         }
1249
1250         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1251                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1252
1253 #ifndef CONFIG_NFS_V3
1254         if (args->flags & NFS_MOUNT_VER3)
1255                 goto out_v3_not_compiled;
1256 #endif /* !CONFIG_NFS_V3 */
1257
1258         return 0;
1259
1260 out_no_data:
1261         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1262         return -EINVAL;
1263
1264 out_no_v3:
1265         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1266                  data->version);
1267         return -EINVAL;
1268
1269 out_no_sec:
1270         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1271         return -EINVAL;
1272
1273 #ifndef CONFIG_NFS_V3
1274 out_v3_not_compiled:
1275         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1276         return -EPROTONOSUPPORT;
1277 #endif /* !CONFIG_NFS_V3 */
1278
1279 out_no_address:
1280         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1281         return -EINVAL;
1282
1283 out_invalid_fh:
1284         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1285         return -EINVAL;
1286 }
1287
1288 /*
1289  * Initialise the common bits of the superblock
1290  */
1291 static inline void nfs_initialise_sb(struct super_block *sb)
1292 {
1293         struct nfs_server *server = NFS_SB(sb);
1294
1295         sb->s_magic = NFS_SUPER_MAGIC;
1296
1297         /* We probably want something more informative here */
1298         snprintf(sb->s_id, sizeof(sb->s_id),
1299                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1300
1301         if (sb->s_blocksize == 0)
1302                 sb->s_blocksize = nfs_block_bits(server->wsize,
1303                                                  &sb->s_blocksize_bits);
1304
1305         if (server->flags & NFS_MOUNT_NOAC)
1306                 sb->s_flags |= MS_SYNCHRONOUS;
1307
1308         nfs_super_set_maxbytes(sb, server->maxfilesize);
1309 }
1310
1311 /*
1312  * Finish setting up an NFS2/3 superblock
1313  */
1314 static void nfs_fill_super(struct super_block *sb,
1315                            struct nfs_parsed_mount_data *data)
1316 {
1317         struct nfs_server *server = NFS_SB(sb);
1318
1319         sb->s_blocksize_bits = 0;
1320         sb->s_blocksize = 0;
1321         if (data->bsize)
1322                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1323
1324         if (server->flags & NFS_MOUNT_VER3) {
1325                 /* The VFS shouldn't apply the umask to mode bits. We will do
1326                  * so ourselves when necessary.
1327                  */
1328                 sb->s_flags |= MS_POSIXACL;
1329                 sb->s_time_gran = 1;
1330         }
1331
1332         sb->s_op = &nfs_sops;
1333         nfs_initialise_sb(sb);
1334 }
1335
1336 /*
1337  * Finish setting up a cloned NFS2/3 superblock
1338  */
1339 static void nfs_clone_super(struct super_block *sb,
1340                             const struct super_block *old_sb)
1341 {
1342         struct nfs_server *server = NFS_SB(sb);
1343
1344         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1345         sb->s_blocksize = old_sb->s_blocksize;
1346         sb->s_maxbytes = old_sb->s_maxbytes;
1347
1348         if (server->flags & NFS_MOUNT_VER3) {
1349                 /* The VFS shouldn't apply the umask to mode bits. We will do
1350                  * so ourselves when necessary.
1351                  */
1352                 sb->s_flags |= MS_POSIXACL;
1353                 sb->s_time_gran = 1;
1354         }
1355
1356         sb->s_op = old_sb->s_op;
1357         nfs_initialise_sb(sb);
1358 }
1359
1360 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1361
1362 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1363 {
1364         const struct nfs_server *a = s->s_fs_info;
1365         const struct rpc_clnt *clnt_a = a->client;
1366         const struct rpc_clnt *clnt_b = b->client;
1367
1368         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1369                 goto Ebusy;
1370         if (a->nfs_client != b->nfs_client)
1371                 goto Ebusy;
1372         if (a->flags != b->flags)
1373                 goto Ebusy;
1374         if (a->wsize != b->wsize)
1375                 goto Ebusy;
1376         if (a->rsize != b->rsize)
1377                 goto Ebusy;
1378         if (a->acregmin != b->acregmin)
1379                 goto Ebusy;
1380         if (a->acregmax != b->acregmax)
1381                 goto Ebusy;
1382         if (a->acdirmin != b->acdirmin)
1383                 goto Ebusy;
1384         if (a->acdirmax != b->acdirmax)
1385                 goto Ebusy;
1386         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1387                 goto Ebusy;
1388         return 1;
1389 Ebusy:
1390         return 0;
1391 }
1392
1393 struct nfs_sb_mountdata {
1394         struct nfs_server *server;
1395         int mntflags;
1396 };
1397
1398 static int nfs_set_super(struct super_block *s, void *data)
1399 {
1400         struct nfs_sb_mountdata *sb_mntdata = data;
1401         struct nfs_server *server = sb_mntdata->server;
1402         int ret;
1403
1404         s->s_flags = sb_mntdata->mntflags;
1405         s->s_fs_info = server;
1406         ret = set_anon_super(s, server);
1407         if (ret == 0)
1408                 server->s_dev = s->s_dev;
1409         return ret;
1410 }
1411
1412 static int nfs_compare_super_address(struct nfs_server *server1,
1413                                      struct nfs_server *server2)
1414 {
1415         struct sockaddr *sap1, *sap2;
1416
1417         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1418         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1419
1420         if (sap1->sa_family != sap2->sa_family)
1421                 return 0;
1422
1423         switch (sap1->sa_family) {
1424         case AF_INET: {
1425                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1426                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1427                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1428                         return 0;
1429                 if (sin1->sin_port != sin2->sin_port)
1430                         return 0;
1431                 break;
1432         }
1433         case AF_INET6: {
1434                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1435                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1436                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1437                         return 0;
1438                 if (sin1->sin6_port != sin2->sin6_port)
1439                         return 0;
1440                 break;
1441         }
1442         default:
1443                 return 0;
1444         }
1445
1446         return 1;
1447 }
1448
1449 static int nfs_compare_super(struct super_block *sb, void *data)
1450 {
1451         struct nfs_sb_mountdata *sb_mntdata = data;
1452         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1453         int mntflags = sb_mntdata->mntflags;
1454
1455         if (!nfs_compare_super_address(old, server))
1456                 return 0;
1457         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1458         if (old->flags & NFS_MOUNT_UNSHARED)
1459                 return 0;
1460         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1461                 return 0;
1462         return nfs_compare_mount_options(sb, server, mntflags);
1463 }
1464
1465 static int nfs_get_sb(struct file_system_type *fs_type,
1466         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1467 {
1468         struct nfs_server *server = NULL;
1469         struct super_block *s;
1470         struct nfs_fh mntfh;
1471         struct nfs_parsed_mount_data data;
1472         struct dentry *mntroot;
1473         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1474         struct nfs_sb_mountdata sb_mntdata = {
1475                 .mntflags = flags,
1476         };
1477         int error;
1478
1479         /* Validate the mount data */
1480         error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);
1481         if (error < 0)
1482                 goto out;
1483
1484         /* Get a volume representation */
1485         server = nfs_create_server(&data, &mntfh);
1486         if (IS_ERR(server)) {
1487                 error = PTR_ERR(server);
1488                 goto out;
1489         }
1490         sb_mntdata.server = server;
1491
1492         if (server->flags & NFS_MOUNT_UNSHARED)
1493                 compare_super = NULL;
1494
1495         /* Get a superblock - note that we may end up sharing one that already exists */
1496         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1497         if (IS_ERR(s)) {
1498                 error = PTR_ERR(s);
1499                 goto out_err_nosb;
1500         }
1501
1502         if (s->s_fs_info != server) {
1503                 nfs_free_server(server);
1504                 server = NULL;
1505         }
1506
1507         if (!s->s_root) {
1508                 /* initial superblock/root creation */
1509                 nfs_fill_super(s, &data);
1510         }
1511
1512         mntroot = nfs_get_root(s, &mntfh);
1513         if (IS_ERR(mntroot)) {
1514                 error = PTR_ERR(mntroot);
1515                 goto error_splat_super;
1516         }
1517
1518         s->s_flags |= MS_ACTIVE;
1519         mnt->mnt_sb = s;
1520         mnt->mnt_root = mntroot;
1521         error = 0;
1522
1523 out:
1524         kfree(data.nfs_server.hostname);
1525         kfree(data.mount_server.hostname);
1526         return error;
1527
1528 out_err_nosb:
1529         nfs_free_server(server);
1530         goto out;
1531
1532 error_splat_super:
1533         up_write(&s->s_umount);
1534         deactivate_super(s);
1535         goto out;
1536 }
1537
1538 /*
1539  * Destroy an NFS2/3 superblock
1540  */
1541 static void nfs_kill_super(struct super_block *s)
1542 {
1543         struct nfs_server *server = NFS_SB(s);
1544
1545         kill_anon_super(s);
1546         nfs_free_server(server);
1547 }
1548
1549 /*
1550  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1551  */
1552 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1553                            const char *dev_name, void *raw_data,
1554                            struct vfsmount *mnt)
1555 {
1556         struct nfs_clone_mount *data = raw_data;
1557         struct super_block *s;
1558         struct nfs_server *server;
1559         struct dentry *mntroot;
1560         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1561         struct nfs_sb_mountdata sb_mntdata = {
1562                 .mntflags = flags,
1563         };
1564         int error;
1565
1566         dprintk("--> nfs_xdev_get_sb()\n");
1567
1568         /* create a new volume representation */
1569         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1570         if (IS_ERR(server)) {
1571                 error = PTR_ERR(server);
1572                 goto out_err_noserver;
1573         }
1574         sb_mntdata.server = server;
1575
1576         if (server->flags & NFS_MOUNT_UNSHARED)
1577                 compare_super = NULL;
1578
1579         /* Get a superblock - note that we may end up sharing one that already exists */
1580         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1581         if (IS_ERR(s)) {
1582                 error = PTR_ERR(s);
1583                 goto out_err_nosb;
1584         }
1585
1586         if (s->s_fs_info != server) {
1587                 nfs_free_server(server);
1588                 server = NULL;
1589         }
1590
1591         if (!s->s_root) {
1592                 /* initial superblock/root creation */
1593                 nfs_clone_super(s, data->sb);
1594         }
1595
1596         mntroot = nfs_get_root(s, data->fh);
1597         if (IS_ERR(mntroot)) {
1598                 error = PTR_ERR(mntroot);
1599                 goto error_splat_super;
1600         }
1601         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1602                 dput(mntroot);
1603                 error = -ESTALE;
1604                 goto error_splat_super;
1605         }
1606
1607         s->s_flags |= MS_ACTIVE;
1608         mnt->mnt_sb = s;
1609         mnt->mnt_root = mntroot;
1610
1611         dprintk("<-- nfs_xdev_get_sb() = 0\n");
1612         return 0;
1613
1614 out_err_nosb:
1615         nfs_free_server(server);
1616 out_err_noserver:
1617         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
1618         return error;
1619
1620 error_splat_super:
1621         up_write(&s->s_umount);
1622         deactivate_super(s);
1623         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
1624         return error;
1625 }
1626
1627 #ifdef CONFIG_NFS_V4
1628
1629 /*
1630  * Finish setting up a cloned NFS4 superblock
1631  */
1632 static void nfs4_clone_super(struct super_block *sb,
1633                             const struct super_block *old_sb)
1634 {
1635         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1636         sb->s_blocksize = old_sb->s_blocksize;
1637         sb->s_maxbytes = old_sb->s_maxbytes;
1638         sb->s_time_gran = 1;
1639         sb->s_op = old_sb->s_op;
1640         nfs_initialise_sb(sb);
1641 }
1642
1643 /*
1644  * Set up an NFS4 superblock
1645  */
1646 static void nfs4_fill_super(struct super_block *sb)
1647 {
1648         sb->s_time_gran = 1;
1649         sb->s_op = &nfs4_sops;
1650         nfs_initialise_sb(sb);
1651 }
1652
1653 /*
1654  * If the user didn't specify a port, set the port number to
1655  * the NFS version 4 default port.
1656  */
1657 static void nfs4_default_port(struct sockaddr *sap)
1658 {
1659         switch (sap->sa_family) {
1660         case AF_INET: {
1661                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
1662                 if (ap->sin_port == 0)
1663                         ap->sin_port = htons(NFS_PORT);
1664                 break;
1665         }
1666         case AF_INET6: {
1667                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
1668                 if (ap->sin6_port == 0)
1669                         ap->sin6_port = htons(NFS_PORT);
1670                 break;
1671         }
1672         }
1673 }
1674
1675 /*
1676  * Validate NFSv4 mount options
1677  */
1678 static int nfs4_validate_mount_data(void *options,
1679                                     struct nfs_parsed_mount_data *args,
1680                                     const char *dev_name)
1681 {
1682         struct sockaddr_in *ap;
1683         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
1684         char *c;
1685
1686         memset(args, 0, sizeof(*args));
1687
1688         if (data == NULL)
1689                 goto out_no_data;
1690
1691         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1692         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1693         args->timeo             = 600;
1694         args->retrans           = 2;
1695         args->acregmin          = 3;
1696         args->acregmax          = 60;
1697         args->acdirmin          = 30;
1698         args->acdirmax          = 60;
1699         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1700
1701         switch (data->version) {
1702         case 1:
1703                 ap = (struct sockaddr_in *)&args->nfs_server.address;
1704                 if (data->host_addrlen > sizeof(args->nfs_server.address))
1705                         goto out_no_address;
1706                 if (data->host_addrlen == 0)
1707                         goto out_no_address;
1708                 args->nfs_server.addrlen = data->host_addrlen;
1709                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
1710                         return -EFAULT;
1711                 if (!nfs_verify_server_address((struct sockaddr *)
1712                                                 &args->nfs_server.address))
1713                         goto out_no_address;
1714
1715                 nfs4_default_port((struct sockaddr *)
1716                                   &args->nfs_server.address);
1717
1718                 switch (data->auth_flavourlen) {
1719                 case 0:
1720                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1721                         break;
1722                 case 1:
1723                         if (copy_from_user(&args->auth_flavors[0],
1724                                            data->auth_flavours,
1725                                            sizeof(args->auth_flavors[0])))
1726                                 return -EFAULT;
1727                         break;
1728                 default:
1729                         goto out_inval_auth;
1730                 }
1731
1732                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1733                 if (IS_ERR(c))
1734                         return PTR_ERR(c);
1735                 args->nfs_server.hostname = c;
1736
1737                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1738                 if (IS_ERR(c))
1739                         return PTR_ERR(c);
1740                 args->nfs_server.export_path = c;
1741                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1742
1743                 c = strndup_user(data->client_addr.data, 16);
1744                 if (IS_ERR(c))
1745                         return PTR_ERR(c);
1746                 args->client_address = c;
1747
1748                 /*
1749                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
1750                  * can deal with.
1751                  */
1752
1753                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
1754                 args->rsize     = data->rsize;
1755                 args->wsize     = data->wsize;
1756                 args->timeo     = data->timeo;
1757                 args->retrans   = data->retrans;
1758                 args->acregmin  = data->acregmin;
1759                 args->acregmax  = data->acregmax;
1760                 args->acdirmin  = data->acdirmin;
1761                 args->acdirmax  = data->acdirmax;
1762                 args->nfs_server.protocol = data->proto;
1763
1764                 break;
1765         default: {
1766                 unsigned int len;
1767
1768                 if (nfs_parse_mount_options((char *)options, args) == 0)
1769                         return -EINVAL;
1770
1771                 if (!nfs_verify_server_address((struct sockaddr *)
1772                                                 &args->nfs_server.address))
1773                         return -EINVAL;
1774
1775                 nfs4_default_port((struct sockaddr *)
1776                                   &args->nfs_server.address);
1777
1778                 switch (args->auth_flavor_len) {
1779                 case 0:
1780                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1781                         break;
1782                 case 1:
1783                         break;
1784                 default:
1785                         goto out_inval_auth;
1786                 }
1787
1788                 /*
1789                  * Split "dev_name" into "hostname:mntpath".
1790                  */
1791                 c = strchr(dev_name, ':');
1792                 if (c == NULL)
1793                         return -EINVAL;
1794                 /* while calculating len, pretend ':' is '\0' */
1795                 len = c - dev_name;
1796                 if (len > NFS4_MAXNAMLEN)
1797                         return -ENAMETOOLONG;
1798                 /* N.B. caller will free nfs_server.hostname in all cases */
1799                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1800
1801                 c++;                    /* step over the ':' */
1802                 len = strlen(c);
1803                 if (len > NFS4_MAXPATHLEN)
1804                         return -ENAMETOOLONG;
1805                 args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
1806
1807                 dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);
1808
1809                 if (args->client_address == NULL)
1810                         goto out_no_client_address;
1811
1812                 break;
1813                 }
1814         }
1815
1816         return 0;
1817
1818 out_no_data:
1819         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
1820         return -EINVAL;
1821
1822 out_inval_auth:
1823         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
1824                  data->auth_flavourlen);
1825         return -EINVAL;
1826
1827 out_no_address:
1828         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
1829         return -EINVAL;
1830
1831 out_no_client_address:
1832         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
1833         return -EINVAL;
1834 }
1835
1836 /*
1837  * Get the superblock for an NFS4 mountpoint
1838  */
1839 static int nfs4_get_sb(struct file_system_type *fs_type,
1840         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1841 {
1842         struct nfs_parsed_mount_data data;
1843         struct super_block *s;
1844         struct nfs_server *server;
1845         struct nfs_fh mntfh;
1846         struct dentry *mntroot;
1847         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1848         struct nfs_sb_mountdata sb_mntdata = {
1849                 .mntflags = flags,
1850         };
1851         int error;
1852
1853         /* Validate the mount data */
1854         error = nfs4_validate_mount_data(raw_data, &data, dev_name);
1855         if (error < 0)
1856                 goto out;
1857
1858         /* Get a volume representation */
1859         server = nfs4_create_server(&data, &mntfh);
1860         if (IS_ERR(server)) {
1861                 error = PTR_ERR(server);
1862                 goto out;
1863         }
1864         sb_mntdata.server = server;
1865
1866         if (server->flags & NFS4_MOUNT_UNSHARED)
1867                 compare_super = NULL;
1868
1869         /* Get a superblock - note that we may end up sharing one that already exists */
1870         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1871         if (IS_ERR(s)) {
1872                 error = PTR_ERR(s);
1873                 goto out_free;
1874         }
1875
1876         if (s->s_fs_info != server) {
1877                 nfs_free_server(server);
1878                 server = NULL;
1879         }
1880
1881         if (!s->s_root) {
1882                 /* initial superblock/root creation */
1883                 nfs4_fill_super(s);
1884         }
1885
1886         mntroot = nfs4_get_root(s, &mntfh);
1887         if (IS_ERR(mntroot)) {
1888                 error = PTR_ERR(mntroot);
1889                 goto error_splat_super;
1890         }
1891
1892         s->s_flags |= MS_ACTIVE;
1893         mnt->mnt_sb = s;
1894         mnt->mnt_root = mntroot;
1895         error = 0;
1896
1897 out:
1898         kfree(data.client_address);
1899         kfree(data.nfs_server.export_path);
1900         kfree(data.nfs_server.hostname);
1901         return error;
1902
1903 out_free:
1904         nfs_free_server(server);
1905         goto out;
1906
1907 error_splat_super:
1908         up_write(&s->s_umount);
1909         deactivate_super(s);
1910         goto out;
1911 }
1912
1913 static void nfs4_kill_super(struct super_block *sb)
1914 {
1915         struct nfs_server *server = NFS_SB(sb);
1916
1917         nfs_return_all_delegations(sb);
1918         kill_anon_super(sb);
1919
1920         nfs4_renewd_prepare_shutdown(server);
1921         nfs_free_server(server);
1922 }
1923
1924 /*
1925  * Clone an NFS4 server record on xdev traversal (FSID-change)
1926  */
1927 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
1928                             const char *dev_name, void *raw_data,
1929                             struct vfsmount *mnt)
1930 {
1931         struct nfs_clone_mount *data = raw_data;
1932         struct super_block *s;
1933         struct nfs_server *server;
1934         struct dentry *mntroot;
1935         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1936         struct nfs_sb_mountdata sb_mntdata = {
1937                 .mntflags = flags,
1938         };
1939         int error;
1940
1941         dprintk("--> nfs4_xdev_get_sb()\n");
1942
1943         /* create a new volume representation */
1944         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1945         if (IS_ERR(server)) {
1946                 error = PTR_ERR(server);
1947                 goto out_err_noserver;
1948         }
1949         sb_mntdata.server = server;
1950
1951         if (server->flags & NFS4_MOUNT_UNSHARED)
1952                 compare_super = NULL;
1953
1954         /* Get a superblock - note that we may end up sharing one that already exists */
1955         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1956         if (IS_ERR(s)) {
1957                 error = PTR_ERR(s);
1958                 goto out_err_nosb;
1959         }
1960
1961         if (s->s_fs_info != server) {
1962                 nfs_free_server(server);
1963                 server = NULL;
1964         }
1965
1966         if (!s->s_root) {
1967                 /* initial superblock/root creation */
1968                 nfs4_clone_super(s, data->sb);
1969         }
1970
1971         mntroot = nfs4_get_root(s, data->fh);
1972         if (IS_ERR(mntroot)) {
1973                 error = PTR_ERR(mntroot);
1974                 goto error_splat_super;
1975         }
1976         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1977                 dput(mntroot);
1978                 error = -ESTALE;
1979                 goto error_splat_super;
1980         }
1981
1982         s->s_flags |= MS_ACTIVE;
1983         mnt->mnt_sb = s;
1984         mnt->mnt_root = mntroot;
1985
1986         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
1987         return 0;
1988
1989 out_err_nosb:
1990         nfs_free_server(server);
1991 out_err_noserver:
1992         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
1993         return error;
1994
1995 error_splat_super:
1996         up_write(&s->s_umount);
1997         deactivate_super(s);
1998         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
1999         return error;
2000 }
2001
2002 /*
2003  * Create an NFS4 server record on referral traversal
2004  */
2005 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2006                                 const char *dev_name, void *raw_data,
2007                                 struct vfsmount *mnt)
2008 {
2009         struct nfs_clone_mount *data = raw_data;
2010         struct super_block *s;
2011         struct nfs_server *server;
2012         struct dentry *mntroot;
2013         struct nfs_fh mntfh;
2014         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2015         struct nfs_sb_mountdata sb_mntdata = {
2016                 .mntflags = flags,
2017         };
2018         int error;
2019
2020         dprintk("--> nfs4_referral_get_sb()\n");
2021
2022         /* create a new volume representation */
2023         server = nfs4_create_referral_server(data, &mntfh);
2024         if (IS_ERR(server)) {
2025                 error = PTR_ERR(server);
2026                 goto out_err_noserver;
2027         }
2028         sb_mntdata.server = server;
2029
2030         if (server->flags & NFS4_MOUNT_UNSHARED)
2031                 compare_super = NULL;
2032
2033         /* Get a superblock - note that we may end up sharing one that already exists */
2034         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2035         if (IS_ERR(s)) {
2036                 error = PTR_ERR(s);
2037                 goto out_err_nosb;
2038         }
2039
2040         if (s->s_fs_info != server) {
2041                 nfs_free_server(server);
2042                 server = NULL;
2043         }
2044
2045         if (!s->s_root) {
2046                 /* initial superblock/root creation */
2047                 nfs4_fill_super(s);
2048         }
2049
2050         mntroot = nfs4_get_root(s, &mntfh);
2051         if (IS_ERR(mntroot)) {
2052                 error = PTR_ERR(mntroot);
2053                 goto error_splat_super;
2054         }
2055         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2056                 dput(mntroot);
2057                 error = -ESTALE;
2058                 goto error_splat_super;
2059         }
2060
2061         s->s_flags |= MS_ACTIVE;
2062         mnt->mnt_sb = s;
2063         mnt->mnt_root = mntroot;
2064
2065         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2066         return 0;
2067
2068 out_err_nosb:
2069         nfs_free_server(server);
2070 out_err_noserver:
2071         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2072         return error;
2073
2074 error_splat_super:
2075         up_write(&s->s_umount);
2076         deactivate_super(s);
2077         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2078         return error;
2079 }
2080
2081 #endif /* CONFIG_NFS_V4 */