SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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_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 * clp->retrans_timeo / HZ);
 483         seq_printf(m, ",retrans=%u", clp->retrans_count);
 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         struct sockaddr_in *ap = (void *)sap;
 656
 657         ap->sin_family = AF_INET;
 658         *len = sizeof(*ap);
 659         if (in4_pton(value, -1, (u8 *)&ap->sin_addr.s_addr, '\0', NULL))
 660                 return;
 661
 662         sap->sa_family = AF_UNSPEC;
 663         *len = 0;
 664 }
 665
 666 /*
 667  * Error-check and convert a string of mount options from user space into
 668  * a data structure
 669  */
 670 static int nfs_parse_mount_options(char *raw,
 671                                    struct nfs_parsed_mount_data *mnt)
 672 {
 673         char *p, *string;
 674         unsigned short port = 0;
 675
 676         if (!raw) {
 677                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 678                 return 1;
 679         }
 680         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 681
 682         while ((p = strsep(&raw, ",")) != NULL) {
 683                 substring_t args[MAX_OPT_ARGS];
 684                 int option, token;
 685
 686                 if (!*p)
 687                         continue;
 688
 689                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 690
 691                 token = match_token(p, nfs_mount_option_tokens, args);
 692                 switch (token) {
 693                 case Opt_soft:
 694                         mnt->flags |= NFS_MOUNT_SOFT;
 695                         break;
 696                 case Opt_hard:
 697                         mnt->flags &= ~NFS_MOUNT_SOFT;
 698                         break;
 699                 case Opt_intr:
 700                         mnt->flags |= NFS_MOUNT_INTR;
 701                         break;
 702                 case Opt_nointr:
 703                         mnt->flags &= ~NFS_MOUNT_INTR;
 704                         break;
 705                 case Opt_posix:
 706                         mnt->flags |= NFS_MOUNT_POSIX;
 707                         break;
 708                 case Opt_noposix:
 709                         mnt->flags &= ~NFS_MOUNT_POSIX;
 710                         break;
 711                 case Opt_cto:
 712                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 713                         break;
 714                 case Opt_nocto:
 715                         mnt->flags |= NFS_MOUNT_NOCTO;
 716                         break;
 717                 case Opt_ac:
 718                         mnt->flags &= ~NFS_MOUNT_NOAC;
 719                         break;
 720                 case Opt_noac:
 721                         mnt->flags |= NFS_MOUNT_NOAC;
 722                         break;
 723                 case Opt_lock:
 724                         mnt->flags &= ~NFS_MOUNT_NONLM;
 725                         break;
 726                 case Opt_nolock:
 727                         mnt->flags |= NFS_MOUNT_NONLM;
 728                         break;
 729                 case Opt_v2:
 730                         mnt->flags &= ~NFS_MOUNT_VER3;
 731                         break;
 732                 case Opt_v3:
 733                         mnt->flags |= NFS_MOUNT_VER3;
 734                         break;
 735                 case Opt_udp:
 736                         mnt->flags &= ~NFS_MOUNT_TCP;
 737                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 738                         mnt->timeo = 7;
 739                         mnt->retrans = 5;
 740                         break;
 741                 case Opt_tcp:
 742                         mnt->flags |= NFS_MOUNT_TCP;
 743                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 744                         mnt->timeo = 600;
 745                         mnt->retrans = 2;
 746                         break;
 747                 case Opt_rdma:
 748                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 749                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 750                         mnt->timeo = 600;
 751                         mnt->retrans = 2;
 752                         break;
 753                 case Opt_acl:
 754                         mnt->flags &= ~NFS_MOUNT_NOACL;
 755                         break;
 756                 case Opt_noacl:
 757                         mnt->flags |= NFS_MOUNT_NOACL;
 758                         break;
 759                 case Opt_rdirplus:
 760                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 761                         break;
 762                 case Opt_nordirplus:
 763                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 764                         break;
 765                 case Opt_sharecache:
 766                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 767                         break;
 768                 case Opt_nosharecache:
 769                         mnt->flags |= NFS_MOUNT_UNSHARED;
 770                         break;
 771
 772                 case Opt_port:
 773                         if (match_int(args, &option))
 774                                 return 0;
 775                         if (option < 0 || option > 65535)
 776                                 return 0;
 777                         port = option;
 778                         break;
 779                 case Opt_rsize:
 780                         if (match_int(args, &mnt->rsize))
 781                                 return 0;
 782                         break;
 783                 case Opt_wsize:
 784                         if (match_int(args, &mnt->wsize))
 785                                 return 0;
 786                         break;
 787                 case Opt_bsize:
 788                         if (match_int(args, &option))
 789                                 return 0;
 790                         if (option < 0)
 791                                 return 0;
 792                         mnt->bsize = option;
 793                         break;
 794                 case Opt_timeo:
 795                         if (match_int(args, &mnt->timeo))
 796                                 return 0;
 797                         break;
 798                 case Opt_retrans:
 799                         if (match_int(args, &mnt->retrans))
 800                                 return 0;
 801                         break;
 802                 case Opt_acregmin:
 803                         if (match_int(args, &mnt->acregmin))
 804                                 return 0;
 805                         break;
 806                 case Opt_acregmax:
 807                         if (match_int(args, &mnt->acregmax))
 808                                 return 0;
 809                         break;
 810                 case Opt_acdirmin:
 811                         if (match_int(args, &mnt->acdirmin))
 812                                 return 0;
 813                         break;
 814                 case Opt_acdirmax:
 815                         if (match_int(args, &mnt->acdirmax))
 816                                 return 0;
 817                         break;
 818                 case Opt_actimeo:
 819                         if (match_int(args, &option))
 820                                 return 0;
 821                         if (option < 0)
 822                                 return 0;
 823                         mnt->acregmin =
 824                         mnt->acregmax =
 825                         mnt->acdirmin =
 826                         mnt->acdirmax = option;
 827                         break;
 828                 case Opt_namelen:
 829                         if (match_int(args, &mnt->namlen))
 830                                 return 0;
 831                         break;
 832                 case Opt_mountport:
 833                         if (match_int(args, &option))
 834                                 return 0;
 835                         if (option < 0 || option > 65535)
 836                                 return 0;
 837                         mnt->mount_server.port = option;
 838                         break;
 839                 case Opt_mountvers:
 840                         if (match_int(args, &option))
 841                                 return 0;
 842                         if (option < 0)
 843                                 return 0;
 844                         mnt->mount_server.version = option;
 845                         break;
 846                 case Opt_nfsvers:
 847                         if (match_int(args, &option))
 848                                 return 0;
 849                         switch (option) {
 850                         case 2:
 851                                 mnt->flags &= ~NFS_MOUNT_VER3;
 852                                 break;
 853                         case 3:
 854                                 mnt->flags |= NFS_MOUNT_VER3;
 855                                 break;
 856                         default:
 857                                 goto out_unrec_vers;
 858                         }
 859                         break;
 860
 861                 case Opt_sec:
 862                         string = match_strdup(args);
 863                         if (string == NULL)
 864                                 goto out_nomem;
 865                         token = match_token(string, nfs_secflavor_tokens, args);
 866                         kfree(string);
 867
 868                         /*
 869                          * The flags setting is for v2/v3.  The flavor_len
 870                          * setting is for v4.  v2/v3 also need to know the
 871                          * difference between NULL and UNIX.
 872                          */
 873                         switch (token) {
 874                         case Opt_sec_none:
 875                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 876                                 mnt->auth_flavor_len = 0;
 877                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 878                                 break;
 879                         case Opt_sec_sys:
 880                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 881                                 mnt->auth_flavor_len = 0;
 882                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 883                                 break;
 884                         case Opt_sec_krb5:
 885                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 886                                 mnt->auth_flavor_len = 1;
 887                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 888                                 break;
 889                         case Opt_sec_krb5i:
 890                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 891                                 mnt->auth_flavor_len = 1;
 892                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 893                                 break;
 894                         case Opt_sec_krb5p:
 895                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 896                                 mnt->auth_flavor_len = 1;
 897                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 898                                 break;
 899                         case Opt_sec_lkey:
 900                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 901                                 mnt->auth_flavor_len = 1;
 902                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 903                                 break;
 904                         case Opt_sec_lkeyi:
 905                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 906                                 mnt->auth_flavor_len = 1;
 907                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 908                                 break;
 909                         case Opt_sec_lkeyp:
 910                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 911                                 mnt->auth_flavor_len = 1;
 912                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 913                                 break;
 914                         case Opt_sec_spkm:
 915                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 916                                 mnt->auth_flavor_len = 1;
 917                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
 918                                 break;
 919                         case Opt_sec_spkmi:
 920                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 921                                 mnt->auth_flavor_len = 1;
 922                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
 923                                 break;
 924                         case Opt_sec_spkmp:
 925                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 926                                 mnt->auth_flavor_len = 1;
 927                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
 928                                 break;
 929                         default:
 930                                 goto out_unrec_sec;
 931                         }
 932                         break;
 933                 case Opt_proto:
 934                         string = match_strdup(args);
 935                         if (string == NULL)
 936                                 goto out_nomem;
 937                         token = match_token(string,
 938                                             nfs_xprt_protocol_tokens, args);
 939                         kfree(string);
 940
 941                         switch (token) {
 942                         case Opt_xprt_udp:
 943                                 mnt->flags &= ~NFS_MOUNT_TCP;
 944                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 945                                 mnt->timeo = 7;
 946                                 mnt->retrans = 5;
 947                                 break;
 948                         case Opt_xprt_tcp:
 949                                 mnt->flags |= NFS_MOUNT_TCP;
 950                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 951                                 mnt->timeo = 600;
 952                                 mnt->retrans = 2;
 953                                 break;
 954                         case Opt_xprt_rdma:
 955                                 /* vector side protocols to TCP */
 956                                 mnt->flags |= NFS_MOUNT_TCP;
 957                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 958                                 mnt->timeo = 600;
 959                                 mnt->retrans = 2;
 960                                 break;
 961                         default:
 962                                 goto out_unrec_xprt;
 963                         }
 964                         break;
 965                 case Opt_mountproto:
 966                         string = match_strdup(args);
 967                         if (string == NULL)
 968                                 goto out_nomem;
 969                         token = match_token(string,
 970                                             nfs_xprt_protocol_tokens, args);
 971                         kfree(string);
 972
 973                         switch (token) {
 974                         case Opt_xprt_udp:
 975                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 976                                 break;
 977                         case Opt_xprt_tcp:
 978                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 979                                 break;
 980                         case Opt_xprt_rdma: /* not used for side protocols */
 981                         default:
 982                                 goto out_unrec_xprt;
 983                         }
 984                         break;
 985                 case Opt_addr:
 986                         string = match_strdup(args);
 987                         if (string == NULL)
 988                                 goto out_nomem;
 989                         nfs_parse_server_address(string, (struct sockaddr *)
 990                                                  &mnt->nfs_server.address,
 991                                                  &mnt->nfs_server.addrlen);
 992                         kfree(string);
 993                         break;
 994                 case Opt_clientaddr:
 995                         string = match_strdup(args);
 996                         if (string == NULL)
 997                                 goto out_nomem;
 998                         mnt->client_address = string;
 999                         break;
1000                 case Opt_mounthost:
1001                         string = match_strdup(args);
1002                         if (string == NULL)
1003                                 goto out_nomem;
1004                         mnt->mount_server.hostname = string;
1005                         break;
1006                 case Opt_mountaddr:
1007                         string = match_strdup(args);
1008                         if (string == NULL)
1009                                 goto out_nomem;
1010                         nfs_parse_server_address(string, (struct sockaddr *)
1011                                                  &mnt->mount_server.address,
1012                                                  &mnt->mount_server.addrlen);
1013                         kfree(string);
1014                         break;
1015
1016                 case Opt_userspace:
1017                 case Opt_deprecated:
1018                         break;
1019
1020                 default:
1021                         goto out_unknown;
1022                 }
1023         }
1024
1025         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address, port);
1026
1027         return 1;
1028
1029 out_nomem:
1030         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1031         return 0;
1032
1033 out_unrec_vers:
1034         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1035         return 0;
1036
1037 out_unrec_xprt:
1038         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1039         return 0;
1040
1041 out_unrec_sec:
1042         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1043         return 0;
1044
1045 out_unknown:
1046         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1047         return 0;
1048 }
1049
1050 /*
1051  * Use the remote server's MOUNT service to request the NFS file handle
1052  * corresponding to the provided path.
1053  */
1054 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1055                          struct nfs_fh *root_fh)
1056 {
1057         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1058         char *hostname;
1059         int status;
1060
1061         if (args->mount_server.version == 0) {
1062                 if (args->flags & NFS_MOUNT_VER3)
1063                         args->mount_server.version = NFS_MNT3_VERSION;
1064                 else
1065                         args->mount_server.version = NFS_MNT_VERSION;
1066         }
1067
1068         if (args->mount_server.hostname)
1069                 hostname = args->mount_server.hostname;
1070         else
1071                 hostname = args->nfs_server.hostname;
1072
1073         /*
1074          * Construct the mount server's address.
1075          */
1076         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1077                 memcpy(sap, &args->nfs_server.address,
1078                        args->nfs_server.addrlen);
1079                 args->mount_server.addrlen = args->nfs_server.addrlen;
1080         }
1081
1082         /*
1083          * autobind will be used if mount_server.port == 0
1084          */
1085         nfs_set_port(sap, args->mount_server.port);
1086
1087         /*
1088          * Now ask the mount server to map our export path
1089          * to a file handle.
1090          */
1091         status = nfs_mount(sap,
1092                            args->mount_server.addrlen,
1093                            hostname,
1094                            args->nfs_server.export_path,
1095                            args->mount_server.version,
1096                            args->mount_server.protocol,
1097                            root_fh);
1098         if (status == 0)
1099                 return 0;
1100
1101         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d",
1102                         hostname, status);
1103         return status;
1104 }
1105
1106 /*
1107  * Validate the NFS2/NFS3 mount data
1108  * - fills in the mount root filehandle
1109  *
1110  * For option strings, user space handles the following behaviors:
1111  *
1112  * + DNS: mapping server host name to IP address ("addr=" option)
1113  *
1114  * + failure mode: how to behave if a mount request can't be handled
1115  *   immediately ("fg/bg" option)
1116  *
1117  * + retry: how often to retry a mount request ("retry=" option)
1118  *
1119  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1120  *   mountproto=tcp after mountproto=udp, and so on
1121  */
1122 static int nfs_validate_mount_data(void *options,
1123                                    struct nfs_parsed_mount_data *args,
1124                                    struct nfs_fh *mntfh,
1125                                    const char *dev_name)
1126 {
1127         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1128
1129         memset(args, 0, sizeof(*args));
1130
1131         if (data == NULL)
1132                 goto out_no_data;
1133
1134         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1135         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1136         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1137         args->timeo             = 600;
1138         args->retrans           = 2;
1139         args->acregmin          = 3;
1140         args->acregmax          = 60;
1141         args->acdirmin          = 30;
1142         args->acdirmax          = 60;
1143         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1144         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1145
1146         switch (data->version) {
1147         case 1:
1148                 data->namlen = 0;
1149         case 2:
1150                 data->bsize = 0;
1151         case 3:
1152                 if (data->flags & NFS_MOUNT_VER3)
1153                         goto out_no_v3;
1154                 data->root.size = NFS2_FHSIZE;
1155                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1156         case 4:
1157                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1158                         goto out_no_sec;
1159         case 5:
1160                 memset(data->context, 0, sizeof(data->context));
1161         case 6:
1162                 if (data->flags & NFS_MOUNT_VER3)
1163                         mntfh->size = data->root.size;
1164                 else
1165                         mntfh->size = NFS2_FHSIZE;
1166
1167                 if (mntfh->size > sizeof(mntfh->data))
1168                         goto out_invalid_fh;
1169
1170                 memcpy(mntfh->data, data->root.data, mntfh->size);
1171                 if (mntfh->size < sizeof(mntfh->data))
1172                         memset(mntfh->data + mntfh->size, 0,
1173                                sizeof(mntfh->data) - mntfh->size);
1174
1175                 /*
1176                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1177                  * can deal with.
1178                  */
1179                 args->flags             = data->flags;
1180                 args->rsize             = data->rsize;
1181                 args->wsize             = data->wsize;
1182                 args->flags             = data->flags;
1183                 args->timeo             = data->timeo;
1184                 args->retrans           = data->retrans;
1185                 args->acregmin          = data->acregmin;
1186                 args->acregmax          = data->acregmax;
1187                 args->acdirmin          = data->acdirmin;
1188                 args->acdirmax          = data->acdirmax;
1189
1190                 memcpy(&args->nfs_server.address, &data->addr,
1191                        sizeof(data->addr));
1192                 args->nfs_server.addrlen = sizeof(data->addr);
1193                 if (!nfs_verify_server_address((struct sockaddr *)
1194                                                 &args->nfs_server.address))
1195                         goto out_no_address;
1196
1197                 if (!(data->flags & NFS_MOUNT_TCP))
1198                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1199                 /* N.B. caller will free nfs_server.hostname in all cases */
1200                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1201                 args->namlen            = data->namlen;
1202                 args->bsize             = data->bsize;
1203                 args->auth_flavors[0]   = data->pseudoflavor;
1204                 break;
1205         default: {
1206                 unsigned int len;
1207                 char *c;
1208                 int status;
1209
1210                 if (nfs_parse_mount_options((char *)options, args) == 0)
1211                         return -EINVAL;
1212
1213                 if (!nfs_verify_server_address((struct sockaddr *)
1214                                                 &args->nfs_server.address))
1215                         goto out_no_address;
1216
1217                 c = strchr(dev_name, ':');
1218                 if (c == NULL)
1219                         return -EINVAL;
1220                 len = c - dev_name;
1221                 /* N.B. caller will free nfs_server.hostname in all cases */
1222                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1223
1224                 c++;
1225                 if (strlen(c) > NFS_MAXPATHLEN)
1226                         return -ENAMETOOLONG;
1227                 args->nfs_server.export_path = c;
1228
1229                 status = nfs_try_mount(args, mntfh);
1230                 if (status)
1231                         return status;
1232
1233                 break;
1234                 }
1235         }
1236
1237         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1238                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1239
1240 #ifndef CONFIG_NFS_V3
1241         if (args->flags & NFS_MOUNT_VER3)
1242                 goto out_v3_not_compiled;
1243 #endif /* !CONFIG_NFS_V3 */
1244
1245         return 0;
1246
1247 out_no_data:
1248         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1249         return -EINVAL;
1250
1251 out_no_v3:
1252         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1253                  data->version);
1254         return -EINVAL;
1255
1256 out_no_sec:
1257         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1258         return -EINVAL;
1259
1260 #ifndef CONFIG_NFS_V3
1261 out_v3_not_compiled:
1262         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1263         return -EPROTONOSUPPORT;
1264 #endif /* !CONFIG_NFS_V3 */
1265
1266 out_no_address:
1267         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1268         return -EINVAL;
1269
1270 out_invalid_fh:
1271         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1272         return -EINVAL;
1273 }
1274
1275 /*
1276  * Initialise the common bits of the superblock
1277  */
1278 static inline void nfs_initialise_sb(struct super_block *sb)
1279 {
1280         struct nfs_server *server = NFS_SB(sb);
1281
1282         sb->s_magic = NFS_SUPER_MAGIC;
1283
1284         /* We probably want something more informative here */
1285         snprintf(sb->s_id, sizeof(sb->s_id),
1286                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1287
1288         if (sb->s_blocksize == 0)
1289                 sb->s_blocksize = nfs_block_bits(server->wsize,
1290                                                  &sb->s_blocksize_bits);
1291
1292         if (server->flags & NFS_MOUNT_NOAC)
1293                 sb->s_flags |= MS_SYNCHRONOUS;
1294
1295         nfs_super_set_maxbytes(sb, server->maxfilesize);
1296 }
1297
1298 /*
1299  * Finish setting up an NFS2/3 superblock
1300  */
1301 static void nfs_fill_super(struct super_block *sb,
1302                            struct nfs_parsed_mount_data *data)
1303 {
1304         struct nfs_server *server = NFS_SB(sb);
1305
1306         sb->s_blocksize_bits = 0;
1307         sb->s_blocksize = 0;
1308         if (data->bsize)
1309                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1310
1311         if (server->flags & NFS_MOUNT_VER3) {
1312                 /* The VFS shouldn't apply the umask to mode bits. We will do
1313                  * so ourselves when necessary.
1314                  */
1315                 sb->s_flags |= MS_POSIXACL;
1316                 sb->s_time_gran = 1;
1317         }
1318
1319         sb->s_op = &nfs_sops;
1320         nfs_initialise_sb(sb);
1321 }
1322
1323 /*
1324  * Finish setting up a cloned NFS2/3 superblock
1325  */
1326 static void nfs_clone_super(struct super_block *sb,
1327                             const struct super_block *old_sb)
1328 {
1329         struct nfs_server *server = NFS_SB(sb);
1330
1331         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1332         sb->s_blocksize = old_sb->s_blocksize;
1333         sb->s_maxbytes = old_sb->s_maxbytes;
1334
1335         if (server->flags & NFS_MOUNT_VER3) {
1336                 /* The VFS shouldn't apply the umask to mode bits. We will do
1337                  * so ourselves when necessary.
1338                  */
1339                 sb->s_flags |= MS_POSIXACL;
1340                 sb->s_time_gran = 1;
1341         }
1342
1343         sb->s_op = old_sb->s_op;
1344         nfs_initialise_sb(sb);
1345 }
1346
1347 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1348
1349 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1350 {
1351         const struct nfs_server *a = s->s_fs_info;
1352         const struct rpc_clnt *clnt_a = a->client;
1353         const struct rpc_clnt *clnt_b = b->client;
1354
1355         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1356                 goto Ebusy;
1357         if (a->nfs_client != b->nfs_client)
1358                 goto Ebusy;
1359         if (a->flags != b->flags)
1360                 goto Ebusy;
1361         if (a->wsize != b->wsize)
1362                 goto Ebusy;
1363         if (a->rsize != b->rsize)
1364                 goto Ebusy;
1365         if (a->acregmin != b->acregmin)
1366                 goto Ebusy;
1367         if (a->acregmax != b->acregmax)
1368                 goto Ebusy;
1369         if (a->acdirmin != b->acdirmin)
1370                 goto Ebusy;
1371         if (a->acdirmax != b->acdirmax)
1372                 goto Ebusy;
1373         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1374                 goto Ebusy;
1375         return 1;
1376 Ebusy:
1377         return 0;
1378 }
1379
1380 struct nfs_sb_mountdata {
1381         struct nfs_server *server;
1382         int mntflags;
1383 };
1384
1385 static int nfs_set_super(struct super_block *s, void *data)
1386 {
1387         struct nfs_sb_mountdata *sb_mntdata = data;
1388         struct nfs_server *server = sb_mntdata->server;
1389         int ret;
1390
1391         s->s_flags = sb_mntdata->mntflags;
1392         s->s_fs_info = server;
1393         ret = set_anon_super(s, server);
1394         if (ret == 0)
1395                 server->s_dev = s->s_dev;
1396         return ret;
1397 }
1398
1399 static int nfs_compare_super_address(struct nfs_server *server1,
1400                                      struct nfs_server *server2)
1401 {
1402         struct sockaddr *sap1, *sap2;
1403
1404         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1405         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1406
1407         if (sap1->sa_family != sap2->sa_family)
1408                 return 0;
1409
1410         switch (sap1->sa_family) {
1411         case AF_INET: {
1412                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1413                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1414                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1415                         return 0;
1416                 if (sin1->sin_port != sin2->sin_port)
1417                         return 0;
1418                 break;
1419         }
1420         case AF_INET6: {
1421                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1422                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1423                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1424                         return 0;
1425                 if (sin1->sin6_port != sin2->sin6_port)
1426                         return 0;
1427                 break;
1428         }
1429         default:
1430                 return 0;
1431         }
1432
1433         return 1;
1434 }
1435
1436 static int nfs_compare_super(struct super_block *sb, void *data)
1437 {
1438         struct nfs_sb_mountdata *sb_mntdata = data;
1439         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1440         int mntflags = sb_mntdata->mntflags;
1441
1442         if (!nfs_compare_super_address(old, server))
1443                 return 0;
1444         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1445         if (old->flags & NFS_MOUNT_UNSHARED)
1446                 return 0;
1447         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1448                 return 0;
1449         return nfs_compare_mount_options(sb, server, mntflags);
1450 }
1451
1452 static int nfs_get_sb(struct file_system_type *fs_type,
1453         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1454 {
1455         struct nfs_server *server = NULL;
1456         struct super_block *s;
1457         struct nfs_fh mntfh;
1458         struct nfs_parsed_mount_data data;
1459         struct dentry *mntroot;
1460         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1461         struct nfs_sb_mountdata sb_mntdata = {
1462                 .mntflags = flags,
1463         };
1464         int error;
1465
1466         /* Validate the mount data */
1467         error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);
1468         if (error < 0)
1469                 goto out;
1470
1471         /* Get a volume representation */
1472         server = nfs_create_server(&data, &mntfh);
1473         if (IS_ERR(server)) {
1474                 error = PTR_ERR(server);
1475                 goto out;
1476         }
1477         sb_mntdata.server = server;
1478
1479         if (server->flags & NFS_MOUNT_UNSHARED)
1480                 compare_super = NULL;
1481
1482         /* Get a superblock - note that we may end up sharing one that already exists */
1483         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1484         if (IS_ERR(s)) {
1485                 error = PTR_ERR(s);
1486                 goto out_err_nosb;
1487         }
1488
1489         if (s->s_fs_info != server) {
1490                 nfs_free_server(server);
1491                 server = NULL;
1492         }
1493
1494         if (!s->s_root) {
1495                 /* initial superblock/root creation */
1496                 nfs_fill_super(s, &data);
1497         }
1498
1499         mntroot = nfs_get_root(s, &mntfh);
1500         if (IS_ERR(mntroot)) {
1501                 error = PTR_ERR(mntroot);
1502                 goto error_splat_super;
1503         }
1504
1505         s->s_flags |= MS_ACTIVE;
1506         mnt->mnt_sb = s;
1507         mnt->mnt_root = mntroot;
1508         error = 0;
1509
1510 out:
1511         kfree(data.nfs_server.hostname);
1512         kfree(data.mount_server.hostname);
1513         return error;
1514
1515 out_err_nosb:
1516         nfs_free_server(server);
1517         goto out;
1518
1519 error_splat_super:
1520         up_write(&s->s_umount);
1521         deactivate_super(s);
1522         goto out;
1523 }
1524
1525 /*
1526  * Destroy an NFS2/3 superblock
1527  */
1528 static void nfs_kill_super(struct super_block *s)
1529 {
1530         struct nfs_server *server = NFS_SB(s);
1531
1532         kill_anon_super(s);
1533         nfs_free_server(server);
1534 }
1535
1536 /*
1537  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1538  */
1539 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1540                            const char *dev_name, void *raw_data,
1541                            struct vfsmount *mnt)
1542 {
1543         struct nfs_clone_mount *data = raw_data;
1544         struct super_block *s;
1545         struct nfs_server *server;
1546         struct dentry *mntroot;
1547         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1548         struct nfs_sb_mountdata sb_mntdata = {
1549                 .mntflags = flags,
1550         };
1551         int error;
1552
1553         dprintk("--> nfs_xdev_get_sb()\n");
1554
1555         /* create a new volume representation */
1556         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1557         if (IS_ERR(server)) {
1558                 error = PTR_ERR(server);
1559                 goto out_err_noserver;
1560         }
1561         sb_mntdata.server = server;
1562
1563         if (server->flags & NFS_MOUNT_UNSHARED)
1564                 compare_super = NULL;
1565
1566         /* Get a superblock - note that we may end up sharing one that already exists */
1567         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1568         if (IS_ERR(s)) {
1569                 error = PTR_ERR(s);
1570                 goto out_err_nosb;
1571         }
1572
1573         if (s->s_fs_info != server) {
1574                 nfs_free_server(server);
1575                 server = NULL;
1576         }
1577
1578         if (!s->s_root) {
1579                 /* initial superblock/root creation */
1580                 nfs_clone_super(s, data->sb);
1581         }
1582
1583         mntroot = nfs_get_root(s, data->fh);
1584         if (IS_ERR(mntroot)) {
1585                 error = PTR_ERR(mntroot);
1586                 goto error_splat_super;
1587         }
1588         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1589                 dput(mntroot);
1590                 error = -ESTALE;
1591                 goto error_splat_super;
1592         }
1593
1594         s->s_flags |= MS_ACTIVE;
1595         mnt->mnt_sb = s;
1596         mnt->mnt_root = mntroot;
1597
1598         dprintk("<-- nfs_xdev_get_sb() = 0\n");
1599         return 0;
1600
1601 out_err_nosb:
1602         nfs_free_server(server);
1603 out_err_noserver:
1604         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
1605         return error;
1606
1607 error_splat_super:
1608         up_write(&s->s_umount);
1609         deactivate_super(s);
1610         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
1611         return error;
1612 }
1613
1614 #ifdef CONFIG_NFS_V4
1615
1616 /*
1617  * Finish setting up a cloned NFS4 superblock
1618  */
1619 static void nfs4_clone_super(struct super_block *sb,
1620                             const struct super_block *old_sb)
1621 {
1622         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1623         sb->s_blocksize = old_sb->s_blocksize;
1624         sb->s_maxbytes = old_sb->s_maxbytes;
1625         sb->s_time_gran = 1;
1626         sb->s_op = old_sb->s_op;
1627         nfs_initialise_sb(sb);
1628 }
1629
1630 /*
1631  * Set up an NFS4 superblock
1632  */
1633 static void nfs4_fill_super(struct super_block *sb)
1634 {
1635         sb->s_time_gran = 1;
1636         sb->s_op = &nfs4_sops;
1637         nfs_initialise_sb(sb);
1638 }
1639
1640 /*
1641  * If the user didn't specify a port, set the port number to
1642  * the NFS version 4 default port.
1643  */
1644 static void nfs4_default_port(struct sockaddr *sap)
1645 {
1646         switch (sap->sa_family) {
1647         case AF_INET: {
1648                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
1649                 if (ap->sin_port == 0)
1650                         ap->sin_port = htons(NFS_PORT);
1651                 break;
1652         }
1653         case AF_INET6: {
1654                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
1655                 if (ap->sin6_port == 0)
1656                         ap->sin6_port = htons(NFS_PORT);
1657                 break;
1658         }
1659         }
1660 }
1661
1662 /*
1663  * Validate NFSv4 mount options
1664  */
1665 static int nfs4_validate_mount_data(void *options,
1666                                     struct nfs_parsed_mount_data *args,
1667                                     const char *dev_name)
1668 {
1669         struct sockaddr_in *ap;
1670         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
1671         char *c;
1672
1673         memset(args, 0, sizeof(*args));
1674
1675         if (data == NULL)
1676                 goto out_no_data;
1677
1678         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1679         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1680         args->timeo             = 600;
1681         args->retrans           = 2;
1682         args->acregmin          = 3;
1683         args->acregmax          = 60;
1684         args->acdirmin          = 30;
1685         args->acdirmax          = 60;
1686         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1687
1688         switch (data->version) {
1689         case 1:
1690                 ap = (struct sockaddr_in *)&args->nfs_server.address;
1691                 if (data->host_addrlen > sizeof(args->nfs_server.address))
1692                         goto out_no_address;
1693                 if (data->host_addrlen == 0)
1694                         goto out_no_address;
1695                 args->nfs_server.addrlen = data->host_addrlen;
1696                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
1697                         return -EFAULT;
1698                 if (!nfs_verify_server_address((struct sockaddr *)
1699                                                 &args->nfs_server.address))
1700                         goto out_no_address;
1701
1702                 nfs4_default_port((struct sockaddr *)
1703                                   &args->nfs_server.address);
1704
1705                 switch (data->auth_flavourlen) {
1706                 case 0:
1707                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1708                         break;
1709                 case 1:
1710                         if (copy_from_user(&args->auth_flavors[0],
1711                                            data->auth_flavours,
1712                                            sizeof(args->auth_flavors[0])))
1713                                 return -EFAULT;
1714                         break;
1715                 default:
1716                         goto out_inval_auth;
1717                 }
1718
1719                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1720                 if (IS_ERR(c))
1721                         return PTR_ERR(c);
1722                 args->nfs_server.hostname = c;
1723
1724                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1725                 if (IS_ERR(c))
1726                         return PTR_ERR(c);
1727                 args->nfs_server.export_path = c;
1728                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1729
1730                 c = strndup_user(data->client_addr.data, 16);
1731                 if (IS_ERR(c))
1732                         return PTR_ERR(c);
1733                 args->client_address = c;
1734
1735                 /*
1736                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
1737                  * can deal with.
1738                  */
1739
1740                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
1741                 args->rsize     = data->rsize;
1742                 args->wsize     = data->wsize;
1743                 args->timeo     = data->timeo;
1744                 args->retrans   = data->retrans;
1745                 args->acregmin  = data->acregmin;
1746                 args->acregmax  = data->acregmax;
1747                 args->acdirmin  = data->acdirmin;
1748                 args->acdirmax  = data->acdirmax;
1749                 args->nfs_server.protocol = data->proto;
1750
1751                 break;
1752         default: {
1753                 unsigned int len;
1754
1755                 if (nfs_parse_mount_options((char *)options, args) == 0)
1756                         return -EINVAL;
1757
1758                 if (!nfs_verify_server_address((struct sockaddr *)
1759                                                 &args->nfs_server.address))
1760                         return -EINVAL;
1761
1762                 nfs4_default_port((struct sockaddr *)
1763                                   &args->nfs_server.address);
1764
1765                 switch (args->auth_flavor_len) {
1766                 case 0:
1767                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1768                         break;
1769                 case 1:
1770                         break;
1771                 default:
1772                         goto out_inval_auth;
1773                 }
1774
1775                 /*
1776                  * Split "dev_name" into "hostname:mntpath".
1777                  */
1778                 c = strchr(dev_name, ':');
1779                 if (c == NULL)
1780                         return -EINVAL;
1781                 /* while calculating len, pretend ':' is '\0' */
1782                 len = c - dev_name;
1783                 if (len > NFS4_MAXNAMLEN)
1784                         return -ENAMETOOLONG;
1785                 /* N.B. caller will free nfs_server.hostname in all cases */
1786                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1787
1788                 c++;                    /* step over the ':' */
1789                 len = strlen(c);
1790                 if (len > NFS4_MAXPATHLEN)
1791                         return -ENAMETOOLONG;
1792                 args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
1793
1794                 dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);
1795
1796                 if (args->client_address == NULL)
1797                         goto out_no_client_address;
1798
1799                 break;
1800                 }
1801         }
1802
1803         return 0;
1804
1805 out_no_data:
1806         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
1807         return -EINVAL;
1808
1809 out_inval_auth:
1810         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
1811                  data->auth_flavourlen);
1812         return -EINVAL;
1813
1814 out_no_address:
1815         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
1816         return -EINVAL;
1817
1818 out_no_client_address:
1819         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
1820         return -EINVAL;
1821 }
1822
1823 /*
1824  * Get the superblock for an NFS4 mountpoint
1825  */
1826 static int nfs4_get_sb(struct file_system_type *fs_type,
1827         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1828 {
1829         struct nfs_parsed_mount_data data;
1830         struct super_block *s;
1831         struct nfs_server *server;
1832         struct nfs_fh mntfh;
1833         struct dentry *mntroot;
1834         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1835         struct nfs_sb_mountdata sb_mntdata = {
1836                 .mntflags = flags,
1837         };
1838         int error;
1839
1840         /* Validate the mount data */
1841         error = nfs4_validate_mount_data(raw_data, &data, dev_name);
1842         if (error < 0)
1843                 goto out;
1844
1845         /* Get a volume representation */
1846         server = nfs4_create_server(&data, &mntfh);
1847         if (IS_ERR(server)) {
1848                 error = PTR_ERR(server);
1849                 goto out;
1850         }
1851         sb_mntdata.server = server;
1852
1853         if (server->flags & NFS4_MOUNT_UNSHARED)
1854                 compare_super = NULL;
1855
1856         /* Get a superblock - note that we may end up sharing one that already exists */
1857         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1858         if (IS_ERR(s)) {
1859                 error = PTR_ERR(s);
1860                 goto out_free;
1861         }
1862
1863         if (s->s_fs_info != server) {
1864                 nfs_free_server(server);
1865                 server = NULL;
1866         }
1867
1868         if (!s->s_root) {
1869                 /* initial superblock/root creation */
1870                 nfs4_fill_super(s);
1871         }
1872
1873         mntroot = nfs4_get_root(s, &mntfh);
1874         if (IS_ERR(mntroot)) {
1875                 error = PTR_ERR(mntroot);
1876                 goto error_splat_super;
1877         }
1878
1879         s->s_flags |= MS_ACTIVE;
1880         mnt->mnt_sb = s;
1881         mnt->mnt_root = mntroot;
1882         error = 0;
1883
1884 out:
1885         kfree(data.client_address);
1886         kfree(data.nfs_server.export_path);
1887         kfree(data.nfs_server.hostname);
1888         return error;
1889
1890 out_free:
1891         nfs_free_server(server);
1892         goto out;
1893
1894 error_splat_super:
1895         up_write(&s->s_umount);
1896         deactivate_super(s);
1897         goto out;
1898 }
1899
1900 static void nfs4_kill_super(struct super_block *sb)
1901 {
1902         struct nfs_server *server = NFS_SB(sb);
1903
1904         nfs_return_all_delegations(sb);
1905         kill_anon_super(sb);
1906
1907         nfs4_renewd_prepare_shutdown(server);
1908         nfs_free_server(server);
1909 }
1910
1911 /*
1912  * Clone an NFS4 server record on xdev traversal (FSID-change)
1913  */
1914 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
1915                             const char *dev_name, void *raw_data,
1916                             struct vfsmount *mnt)
1917 {
1918         struct nfs_clone_mount *data = raw_data;
1919         struct super_block *s;
1920         struct nfs_server *server;
1921         struct dentry *mntroot;
1922         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1923         struct nfs_sb_mountdata sb_mntdata = {
1924                 .mntflags = flags,
1925         };
1926         int error;
1927
1928         dprintk("--> nfs4_xdev_get_sb()\n");
1929
1930         /* create a new volume representation */
1931         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1932         if (IS_ERR(server)) {
1933                 error = PTR_ERR(server);
1934                 goto out_err_noserver;
1935         }
1936         sb_mntdata.server = server;
1937
1938         if (server->flags & NFS4_MOUNT_UNSHARED)
1939                 compare_super = NULL;
1940
1941         /* Get a superblock - note that we may end up sharing one that already exists */
1942         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1943         if (IS_ERR(s)) {
1944                 error = PTR_ERR(s);
1945                 goto out_err_nosb;
1946         }
1947
1948         if (s->s_fs_info != server) {
1949                 nfs_free_server(server);
1950                 server = NULL;
1951         }
1952
1953         if (!s->s_root) {
1954                 /* initial superblock/root creation */
1955                 nfs4_clone_super(s, data->sb);
1956         }
1957
1958         mntroot = nfs4_get_root(s, data->fh);
1959         if (IS_ERR(mntroot)) {
1960                 error = PTR_ERR(mntroot);
1961                 goto error_splat_super;
1962         }
1963         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1964                 dput(mntroot);
1965                 error = -ESTALE;
1966                 goto error_splat_super;
1967         }
1968
1969         s->s_flags |= MS_ACTIVE;
1970         mnt->mnt_sb = s;
1971         mnt->mnt_root = mntroot;
1972
1973         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
1974         return 0;
1975
1976 out_err_nosb:
1977         nfs_free_server(server);
1978 out_err_noserver:
1979         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
1980         return error;
1981
1982 error_splat_super:
1983         up_write(&s->s_umount);
1984         deactivate_super(s);
1985         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
1986         return error;
1987 }
1988
1989 /*
1990  * Create an NFS4 server record on referral traversal
1991  */
1992 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
1993                                 const char *dev_name, void *raw_data,
1994                                 struct vfsmount *mnt)
1995 {
1996         struct nfs_clone_mount *data = raw_data;
1997         struct super_block *s;
1998         struct nfs_server *server;
1999         struct dentry *mntroot;
2000         struct nfs_fh mntfh;
2001         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2002         struct nfs_sb_mountdata sb_mntdata = {
2003                 .mntflags = flags,
2004         };
2005         int error;
2006
2007         dprintk("--> nfs4_referral_get_sb()\n");
2008
2009         /* create a new volume representation */
2010         server = nfs4_create_referral_server(data, &mntfh);
2011         if (IS_ERR(server)) {
2012                 error = PTR_ERR(server);
2013                 goto out_err_noserver;
2014         }
2015         sb_mntdata.server = server;
2016
2017         if (server->flags & NFS4_MOUNT_UNSHARED)
2018                 compare_super = NULL;
2019
2020         /* Get a superblock - note that we may end up sharing one that already exists */
2021         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2022         if (IS_ERR(s)) {
2023                 error = PTR_ERR(s);
2024                 goto out_err_nosb;
2025         }
2026
2027         if (s->s_fs_info != server) {
2028                 nfs_free_server(server);
2029                 server = NULL;
2030         }
2031
2032         if (!s->s_root) {
2033                 /* initial superblock/root creation */
2034                 nfs4_fill_super(s);
2035         }
2036
2037         mntroot = nfs4_get_root(s, &mntfh);
2038         if (IS_ERR(mntroot)) {
2039                 error = PTR_ERR(mntroot);
2040                 goto error_splat_super;
2041         }
2042         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2043                 dput(mntroot);
2044                 error = -ESTALE;
2045                 goto error_splat_super;
2046         }
2047
2048         s->s_flags |= MS_ACTIVE;
2049         mnt->mnt_sb = s;
2050         mnt->mnt_root = mntroot;
2051
2052         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2053         return 0;
2054
2055 out_err_nosb:
2056         nfs_free_server(server);
2057 out_err_noserver:
2058         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2059         return error;
2060
2061 error_splat_super:
2062         up_write(&s->s_umount);
2063         deactivate_super(s);
2064         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2065         return error;
2066 }
2067
2068 #endif /* CONFIG_NFS_V4 */