fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/smp_lock.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <net/ipv6.h>
  50 #include <linux/nfs_xdr.h>
  51 #include <linux/magic.h>
  52 #include <linux/parser.h>
  53
  54 #include <asm/system.h>
  55 #include <asm/uaccess.h>
  56
  57 #include "nfs4_fs.h"
  58 #include "callback.h"
  59 #include "delegation.h"
  60 #include "iostat.h"
  61 #include "internal.h"
  62
  63 #define NFSDBG_FACILITY         NFSDBG_VFS
  64
  65 enum {
  66         /* Mount options that take no arguments */
  67         Opt_soft, Opt_hard,
  68         Opt_intr, Opt_nointr,
  69         Opt_posix, Opt_noposix,
  70         Opt_cto, Opt_nocto,
  71         Opt_ac, Opt_noac,
  72         Opt_lock, Opt_nolock,
  73         Opt_v2, Opt_v3,
  74         Opt_udp, Opt_tcp, Opt_rdma,
  75         Opt_acl, Opt_noacl,
  76         Opt_rdirplus, Opt_nordirplus,
  77         Opt_sharecache, Opt_nosharecache,
  78
  79         /* Mount options that take integer arguments */
  80         Opt_port,
  81         Opt_rsize, Opt_wsize, Opt_bsize,
  82         Opt_timeo, Opt_retrans,
  83         Opt_acregmin, Opt_acregmax,
  84         Opt_acdirmin, Opt_acdirmax,
  85         Opt_actimeo,
  86         Opt_namelen,
  87         Opt_mountport,
  88         Opt_mountvers,
  89         Opt_nfsvers,
  90
  91         /* Mount options that take string arguments */
  92         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
  93         Opt_addr, Opt_mountaddr, Opt_clientaddr,
  94
  95         /* Mount options that are ignored */
  96         Opt_userspace, Opt_deprecated,
  97
  98         Opt_err
  99 };
 100
 101 static match_table_t nfs_mount_option_tokens = {
 102         { Opt_userspace, "bg" },
 103         { Opt_userspace, "fg" },
 104         { Opt_soft, "soft" },
 105         { Opt_hard, "hard" },
 106         { Opt_intr, "intr" },
 107         { Opt_nointr, "nointr" },
 108         { Opt_posix, "posix" },
 109         { Opt_noposix, "noposix" },
 110         { Opt_cto, "cto" },
 111         { Opt_nocto, "nocto" },
 112         { Opt_ac, "ac" },
 113         { Opt_noac, "noac" },
 114         { Opt_lock, "lock" },
 115         { Opt_nolock, "nolock" },
 116         { Opt_v2, "v2" },
 117         { Opt_v3, "v3" },
 118         { Opt_udp, "udp" },
 119         { Opt_tcp, "tcp" },
 120         { Opt_rdma, "rdma" },
 121         { Opt_acl, "acl" },
 122         { Opt_noacl, "noacl" },
 123         { Opt_rdirplus, "rdirplus" },
 124         { Opt_nordirplus, "nordirplus" },
 125         { Opt_sharecache, "sharecache" },
 126         { Opt_nosharecache, "nosharecache" },
 127
 128         { Opt_port, "port=%u" },
 129         { Opt_rsize, "rsize=%u" },
 130         { Opt_wsize, "wsize=%u" },
 131         { Opt_bsize, "bsize=%u" },
 132         { Opt_timeo, "timeo=%u" },
 133         { Opt_retrans, "retrans=%u" },
 134         { Opt_acregmin, "acregmin=%u" },
 135         { Opt_acregmax, "acregmax=%u" },
 136         { Opt_acdirmin, "acdirmin=%u" },
 137         { Opt_acdirmax, "acdirmax=%u" },
 138         { Opt_actimeo, "actimeo=%u" },
 139         { Opt_userspace, "retry=%u" },
 140         { Opt_namelen, "namlen=%u" },
 141         { Opt_mountport, "mountport=%u" },
 142         { Opt_mountvers, "mountvers=%u" },
 143         { Opt_nfsvers, "nfsvers=%u" },
 144         { Opt_nfsvers, "vers=%u" },
 145
 146         { Opt_sec, "sec=%s" },
 147         { Opt_proto, "proto=%s" },
 148         { Opt_mountproto, "mountproto=%s" },
 149         { Opt_addr, "addr=%s" },
 150         { Opt_clientaddr, "clientaddr=%s" },
 151         { Opt_mounthost, "mounthost=%s" },
 152         { Opt_mountaddr, "mountaddr=%s" },
 153
 154         { Opt_err, NULL }
 155 };
 156
 157 enum {
 158         Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
 159
 160         Opt_xprt_err
 161 };
 162
 163 static match_table_t nfs_xprt_protocol_tokens = {
 164         { Opt_xprt_udp, "udp" },
 165         { Opt_xprt_tcp, "tcp" },
 166         { Opt_xprt_rdma, "rdma" },
 167
 168         { Opt_xprt_err, NULL }
 169 };
 170
 171 enum {
 172         Opt_sec_none, Opt_sec_sys,
 173         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 174         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 175         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 176
 177         Opt_sec_err
 178 };
 179
 180 static match_table_t nfs_secflavor_tokens = {
 181         { Opt_sec_none, "none" },
 182         { Opt_sec_none, "null" },
 183         { Opt_sec_sys, "sys" },
 184
 185         { Opt_sec_krb5, "krb5" },
 186         { Opt_sec_krb5i, "krb5i" },
 187         { Opt_sec_krb5p, "krb5p" },
 188
 189         { Opt_sec_lkey, "lkey" },
 190         { Opt_sec_lkeyi, "lkeyi" },
 191         { Opt_sec_lkeyp, "lkeyp" },
 192
 193         { Opt_sec_spkm, "spkm3" },
 194         { Opt_sec_spkmi, "spkm3i" },
 195         { Opt_sec_spkmp, "spkm3p" },
 196
 197         { Opt_sec_err, NULL }
 198 };
 199
 200
 201 static void nfs_umount_begin(struct super_block *);
 202 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 203 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 204 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 205 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 206 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 207                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 208 static void nfs_kill_super(struct super_block *);
 209 static void nfs_put_super(struct super_block *);
 210
 211 static struct file_system_type nfs_fs_type = {
 212         .owner          = THIS_MODULE,
 213         .name           = "nfs",
 214         .get_sb         = nfs_get_sb,
 215         .kill_sb        = nfs_kill_super,
 216         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 217 };
 218
 219 struct file_system_type nfs_xdev_fs_type = {
 220         .owner          = THIS_MODULE,
 221         .name           = "nfs",
 222         .get_sb         = nfs_xdev_get_sb,
 223         .kill_sb        = nfs_kill_super,
 224         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 225 };
 226
 227 static const struct super_operations nfs_sops = {
 228         .alloc_inode    = nfs_alloc_inode,
 229         .destroy_inode  = nfs_destroy_inode,
 230         .write_inode    = nfs_write_inode,
 231         .put_super      = nfs_put_super,
 232         .statfs         = nfs_statfs,
 233         .clear_inode    = nfs_clear_inode,
 234         .umount_begin   = nfs_umount_begin,
 235         .show_options   = nfs_show_options,
 236         .show_stats     = nfs_show_stats,
 237 };
 238
 239 #ifdef CONFIG_NFS_V4
 240 static int nfs4_get_sb(struct file_system_type *fs_type,
 241         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 242 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 243         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 244 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 245         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 246 static void nfs4_kill_super(struct super_block *sb);
 247
 248 static struct file_system_type nfs4_fs_type = {
 249         .owner          = THIS_MODULE,
 250         .name           = "nfs4",
 251         .get_sb         = nfs4_get_sb,
 252         .kill_sb        = nfs4_kill_super,
 253         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 254 };
 255
 256 struct file_system_type nfs4_xdev_fs_type = {
 257         .owner          = THIS_MODULE,
 258         .name           = "nfs4",
 259         .get_sb         = nfs4_xdev_get_sb,
 260         .kill_sb        = nfs4_kill_super,
 261         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 262 };
 263
 264 struct file_system_type nfs4_referral_fs_type = {
 265         .owner          = THIS_MODULE,
 266         .name           = "nfs4",
 267         .get_sb         = nfs4_referral_get_sb,
 268         .kill_sb        = nfs4_kill_super,
 269         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 270 };
 271
 272 static const struct super_operations nfs4_sops = {
 273         .alloc_inode    = nfs_alloc_inode,
 274         .destroy_inode  = nfs_destroy_inode,
 275         .write_inode    = nfs_write_inode,
 276         .statfs         = nfs_statfs,
 277         .clear_inode    = nfs4_clear_inode,
 278         .umount_begin   = nfs_umount_begin,
 279         .show_options   = nfs_show_options,
 280         .show_stats     = nfs_show_stats,
 281 };
 282 #endif
 283
 284 static struct shrinker acl_shrinker = {
 285         .shrink         = nfs_access_cache_shrinker,
 286         .seeks          = DEFAULT_SEEKS,
 287 };
 288
 289 /*
 290  * Register the NFS filesystems
 291  */
 292 int __init register_nfs_fs(void)
 293 {
 294         int ret;
 295
 296         ret = register_filesystem(&nfs_fs_type);
 297         if (ret < 0)
 298                 goto error_0;
 299
 300         ret = nfs_register_sysctl();
 301         if (ret < 0)
 302                 goto error_1;
 303 #ifdef CONFIG_NFS_V4
 304         ret = register_filesystem(&nfs4_fs_type);
 305         if (ret < 0)
 306                 goto error_2;
 307 #endif
 308         register_shrinker(&acl_shrinker);
 309         return 0;
 310
 311 #ifdef CONFIG_NFS_V4
 312 error_2:
 313         nfs_unregister_sysctl();
 314 #endif
 315 error_1:
 316         unregister_filesystem(&nfs_fs_type);
 317 error_0:
 318         return ret;
 319 }
 320
 321 /*
 322  * Unregister the NFS filesystems
 323  */
 324 void __exit unregister_nfs_fs(void)
 325 {
 326         unregister_shrinker(&acl_shrinker);
 327 #ifdef CONFIG_NFS_V4
 328         unregister_filesystem(&nfs4_fs_type);
 329 #endif
 330         nfs_unregister_sysctl();
 331         unregister_filesystem(&nfs_fs_type);
 332 }
 333
 334 void nfs_sb_active(struct nfs_server *server)
 335 {
 336         atomic_inc(&server->active);
 337 }
 338
 339 void nfs_sb_deactive(struct nfs_server *server)
 340 {
 341         if (atomic_dec_and_test(&server->active))
 342                 wake_up(&server->active_wq);
 343 }
 344
 345 static void nfs_put_super(struct super_block *sb)
 346 {
 347         struct nfs_server *server = NFS_SB(sb);
 348         /*
 349          * Make sure there are no outstanding ops to this server.
 350          * If so, wait for them to finish before allowing the
 351          * unmount to continue.
 352          */
 353         wait_event(server->active_wq, atomic_read(&server->active) == 0);
 354 }
 355
 356 /*
 357  * Deliver file system statistics to userspace
 358  */
 359 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 360 {
 361         struct nfs_server *server = NFS_SB(dentry->d_sb);
 362         unsigned char blockbits;
 363         unsigned long blockres;
 364         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 365         struct nfs_fattr fattr;
 366         struct nfs_fsstat res = {
 367                         .fattr = &fattr,
 368         };
 369         int error;
 370
 371         lock_kernel();
 372
 373         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 374         if (error < 0)
 375                 goto out_err;
 376         buf->f_type = NFS_SUPER_MAGIC;
 377
 378         /*
 379          * Current versions of glibc do not correctly handle the
 380          * case where f_frsize != f_bsize.  Eventually we want to
 381          * report the value of wtmult in this field.
 382          */
 383         buf->f_frsize = dentry->d_sb->s_blocksize;
 384
 385         /*
 386          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 387          * are reported in units of f_frsize.  Linux hasn't had
 388          * an f_frsize field in its statfs struct until recently,
 389          * thus historically Linux's sys_statfs reports these
 390          * fields in units of f_bsize.
 391          */
 392         buf->f_bsize = dentry->d_sb->s_blocksize;
 393         blockbits = dentry->d_sb->s_blocksize_bits;
 394         blockres = (1 << blockbits) - 1;
 395         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 396         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 397         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 398
 399         buf->f_files = res.tfiles;
 400         buf->f_ffree = res.afiles;
 401
 402         buf->f_namelen = server->namelen;
 403
 404         unlock_kernel();
 405         return 0;
 406
 407  out_err:
 408         dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
 409         unlock_kernel();
 410         return error;
 411 }
 412
 413 /*
 414  * Map the security flavour number to a name
 415  */
 416 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 417 {
 418         static const struct {
 419                 rpc_authflavor_t flavour;
 420                 const char *str;
 421         } sec_flavours[] = {
 422                 { RPC_AUTH_NULL, "null" },
 423                 { RPC_AUTH_UNIX, "sys" },
 424                 { RPC_AUTH_GSS_KRB5, "krb5" },
 425                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 426                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 427                 { RPC_AUTH_GSS_LKEY, "lkey" },
 428                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 429                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 430                 { RPC_AUTH_GSS_SPKM, "spkm" },
 431                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 432                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 433                 { UINT_MAX, "unknown" }
 434         };
 435         int i;
 436
 437         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 438                 if (sec_flavours[i].flavour == flavour)
 439                         break;
 440         }
 441         return sec_flavours[i].str;
 442 }
 443
 444 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 445                                     int showdefaults)
 446 {
 447         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 448
 449         switch (sap->sa_family) {
 450         case AF_INET: {
 451                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 452                 seq_printf(m, ",mountaddr=" NIPQUAD_FMT,
 453                                 NIPQUAD(sin->sin_addr.s_addr));
 454                 break;
 455         }
 456         case AF_INET6: {
 457                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 458                 seq_printf(m, ",mountaddr=" NIP6_FMT,
 459                                 NIP6(sin6->sin6_addr));
 460                 break;
 461         }
 462         default:
 463                 if (showdefaults)
 464                         seq_printf(m, ",mountaddr=unspecified");
 465         }
 466
 467         if (nfss->mountd_version || showdefaults)
 468                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 469         if (nfss->mountd_port || showdefaults)
 470                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 471
 472         switch (nfss->mountd_protocol) {
 473         case IPPROTO_UDP:
 474                 seq_printf(m, ",mountproto=udp");
 475                 break;
 476         case IPPROTO_TCP:
 477                 seq_printf(m, ",mountproto=tcp");
 478                 break;
 479         default:
 480                 if (showdefaults)
 481                         seq_printf(m, ",mountproto=auto");
 482         }
 483 }
 484
 485 /*
 486  * Describe the mount options in force on this server representation
 487  */
 488 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 489                                    int showdefaults)
 490 {
 491         static const struct proc_nfs_info {
 492                 int flag;
 493                 const char *str;
 494                 const char *nostr;
 495         } nfs_info[] = {
 496                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 497                 { NFS_MOUNT_INTR, ",intr", ",nointr" },
 498                 { NFS_MOUNT_POSIX, ",posix", "" },
 499                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 500                 { NFS_MOUNT_NOAC, ",noac", "" },
 501                 { NFS_MOUNT_NONLM, ",nolock", "" },
 502                 { NFS_MOUNT_NOACL, ",noacl", "" },
 503                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 504                 { NFS_MOUNT_UNSHARED, ",nosharecache", ""},
 505                 { 0, NULL, NULL }
 506         };
 507         const struct proc_nfs_info *nfs_infop;
 508         struct nfs_client *clp = nfss->nfs_client;
 509         u32 version = clp->rpc_ops->version;
 510
 511         seq_printf(m, ",vers=%u", version);
 512         seq_printf(m, ",rsize=%u", nfss->rsize);
 513         seq_printf(m, ",wsize=%u", nfss->wsize);
 514         if (nfss->bsize != 0)
 515                 seq_printf(m, ",bsize=%u", nfss->bsize);
 516         seq_printf(m, ",namlen=%u", nfss->namelen);
 517         if (nfss->acregmin != 3*HZ || showdefaults)
 518                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 519         if (nfss->acregmax != 60*HZ || showdefaults)
 520                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 521         if (nfss->acdirmin != 30*HZ || showdefaults)
 522                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 523         if (nfss->acdirmax != 60*HZ || showdefaults)
 524                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 525         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 526                 if (nfss->flags & nfs_infop->flag)
 527                         seq_puts(m, nfs_infop->str);
 528                 else
 529                         seq_puts(m, nfs_infop->nostr);
 530         }
 531         seq_printf(m, ",proto=%s",
 532                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 533         if (version == 4) {
 534                 if (nfss->port != NFS_PORT)
 535                         seq_printf(m, ",port=%u", nfss->port);
 536         } else
 537                 if (nfss->port)
 538                         seq_printf(m, ",port=%u", nfss->port);
 539
 540         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 541         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 542         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 543
 544         if (version != 4)
 545                 nfs_show_mountd_options(m, nfss, showdefaults);
 546
 547 #ifdef CONFIG_NFS_V4
 548         if (clp->rpc_ops->version == 4)
 549                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 550 #endif
 551 }
 552
 553 /*
 554  * Describe the mount options on this VFS mountpoint
 555  */
 556 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 557 {
 558         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 559
 560         nfs_show_mount_options(m, nfss, 0);
 561
 562         seq_printf(m, ",addr=%s",
 563                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 564                                                         RPC_DISPLAY_ADDR));
 565
 566         return 0;
 567 }
 568
 569 /*
 570  * Present statistical information for this VFS mountpoint
 571  */
 572 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 573 {
 574         int i, cpu;
 575         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 576         struct rpc_auth *auth = nfss->client->cl_auth;
 577         struct nfs_iostats totals = { };
 578
 579         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 580
 581         /*
 582          * Display all mount option settings
 583          */
 584         seq_printf(m, "\n\topts:\t");
 585         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 586         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 587         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 588         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 589         nfs_show_mount_options(m, nfss, 1);
 590
 591         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 592
 593         seq_printf(m, "\n\tcaps:\t");
 594         seq_printf(m, "caps=0x%x", nfss->caps);
 595         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 596         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 597         seq_printf(m, ",bsize=%u", nfss->bsize);
 598         seq_printf(m, ",namlen=%u", nfss->namelen);
 599
 600 #ifdef CONFIG_NFS_V4
 601         if (nfss->nfs_client->rpc_ops->version == 4) {
 602                 seq_printf(m, "\n\tnfsv4:\t");
 603                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 604                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 605                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 606         }
 607 #endif
 608
 609         /*
 610          * Display security flavor in effect for this mount
 611          */
 612         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 613         if (auth->au_flavor)
 614                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 615
 616         /*
 617          * Display superblock I/O counters
 618          */
 619         for_each_possible_cpu(cpu) {
 620                 struct nfs_iostats *stats;
 621
 622                 preempt_disable();
 623                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 624
 625                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 626                         totals.events[i] += stats->events[i];
 627                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 628                         totals.bytes[i] += stats->bytes[i];
 629
 630                 preempt_enable();
 631         }
 632
 633         seq_printf(m, "\n\tevents:\t");
 634         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 635                 seq_printf(m, "%lu ", totals.events[i]);
 636         seq_printf(m, "\n\tbytes:\t");
 637         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 638                 seq_printf(m, "%Lu ", totals.bytes[i]);
 639         seq_printf(m, "\n");
 640
 641         rpc_print_iostats(m, nfss->client);
 642
 643         return 0;
 644 }
 645
 646 /*
 647  * Begin unmount by attempting to remove all automounted mountpoints we added
 648  * in response to xdev traversals and referrals
 649  */
 650 static void nfs_umount_begin(struct super_block *sb)
 651 {
 652         struct nfs_server *server = NFS_SB(sb);
 653         struct rpc_clnt *rpc;
 654
 655         /* -EIO all pending I/O */
 656         rpc = server->client_acl;
 657         if (!IS_ERR(rpc))
 658                 rpc_killall_tasks(rpc);
 659         rpc = server->client;
 660         if (!IS_ERR(rpc))
 661                 rpc_killall_tasks(rpc);
 662 }
 663
 664 /*
 665  * Set the port number in an address.  Be agnostic about the address family.
 666  */
 667 static void nfs_set_port(struct sockaddr *sap, unsigned short port)
 668 {
 669         switch (sap->sa_family) {
 670         case AF_INET: {
 671                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 672                 ap->sin_port = htons(port);
 673                 break;
 674         }
 675         case AF_INET6: {
 676                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 677                 ap->sin6_port = htons(port);
 678                 break;
 679         }
 680         }
 681 }
 682
 683 /*
 684  * Sanity-check a server address provided by the mount command.
 685  *
 686  * Address family must be initialized, and address must not be
 687  * the ANY address for that family.
 688  */
 689 static int nfs_verify_server_address(struct sockaddr *addr)
 690 {
 691         switch (addr->sa_family) {
 692         case AF_INET: {
 693                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 694                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 695         }
 696         case AF_INET6: {
 697                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 698                 return !ipv6_addr_any(sa);
 699         }
 700         }
 701
 702         return 0;
 703 }
 704
 705 /*
 706  * Parse string addresses passed in via a mount option,
 707  * and construct a sockaddr based on the result.
 708  *
 709  * If address parsing fails, set the sockaddr's address
 710  * family to AF_UNSPEC to force nfs_verify_server_address()
 711  * to punt the mount.
 712  */
 713 static void nfs_parse_server_address(char *value,
 714                                      struct sockaddr *sap,
 715                                      size_t *len)
 716 {
 717         if (strchr(value, ':')) {
 718                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 719                 u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
 720
 721                 ap->sin6_family = AF_INET6;
 722                 *len = sizeof(*ap);
 723                 if (in6_pton(value, -1, addr, '\0', NULL))
 724                         return;
 725         } else {
 726                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 727                 u8 *addr = (u8 *)&ap->sin_addr.s_addr;
 728
 729                 ap->sin_family = AF_INET;
 730                 *len = sizeof(*ap);
 731                 if (in4_pton(value, -1, addr, '\0', NULL))
 732                         return;
 733         }
 734
 735         sap->sa_family = AF_UNSPEC;
 736         *len = 0;
 737 }
 738
 739 /*
 740  * Error-check and convert a string of mount options from user space into
 741  * a data structure
 742  */
 743 static int nfs_parse_mount_options(char *raw,
 744                                    struct nfs_parsed_mount_data *mnt)
 745 {
 746         char *p, *string, *secdata;
 747         int rc;
 748
 749         if (!raw) {
 750                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 751                 return 1;
 752         }
 753         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 754
 755         secdata = alloc_secdata();
 756         if (!secdata)
 757                 goto out_nomem;
 758
 759         rc = security_sb_copy_data(raw, secdata);
 760         if (rc)
 761                 goto out_security_failure;
 762
 763         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 764         if (rc)
 765                 goto out_security_failure;
 766
 767         free_secdata(secdata);
 768
 769         while ((p = strsep(&raw, ",")) != NULL) {
 770                 substring_t args[MAX_OPT_ARGS];
 771                 int option, token;
 772
 773                 if (!*p)
 774                         continue;
 775
 776                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 777
 778                 token = match_token(p, nfs_mount_option_tokens, args);
 779                 switch (token) {
 780                 case Opt_soft:
 781                         mnt->flags |= NFS_MOUNT_SOFT;
 782                         break;
 783                 case Opt_hard:
 784                         mnt->flags &= ~NFS_MOUNT_SOFT;
 785                         break;
 786                 case Opt_intr:
 787                 case Opt_nointr:
 788                         break;
 789                 case Opt_posix:
 790                         mnt->flags |= NFS_MOUNT_POSIX;
 791                         break;
 792                 case Opt_noposix:
 793                         mnt->flags &= ~NFS_MOUNT_POSIX;
 794                         break;
 795                 case Opt_cto:
 796                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 797                         break;
 798                 case Opt_nocto:
 799                         mnt->flags |= NFS_MOUNT_NOCTO;
 800                         break;
 801                 case Opt_ac:
 802                         mnt->flags &= ~NFS_MOUNT_NOAC;
 803                         break;
 804                 case Opt_noac:
 805                         mnt->flags |= NFS_MOUNT_NOAC;
 806                         break;
 807                 case Opt_lock:
 808                         mnt->flags &= ~NFS_MOUNT_NONLM;
 809                         break;
 810                 case Opt_nolock:
 811                         mnt->flags |= NFS_MOUNT_NONLM;
 812                         break;
 813                 case Opt_v2:
 814                         mnt->flags &= ~NFS_MOUNT_VER3;
 815                         break;
 816                 case Opt_v3:
 817                         mnt->flags |= NFS_MOUNT_VER3;
 818                         break;
 819                 case Opt_udp:
 820                         mnt->flags &= ~NFS_MOUNT_TCP;
 821                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 822                         mnt->timeo = 7;
 823                         mnt->retrans = 5;
 824                         break;
 825                 case Opt_tcp:
 826                         mnt->flags |= NFS_MOUNT_TCP;
 827                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 828                         mnt->timeo = 600;
 829                         mnt->retrans = 2;
 830                         break;
 831                 case Opt_rdma:
 832                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 833                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 834                         mnt->timeo = 600;
 835                         mnt->retrans = 2;
 836                         break;
 837                 case Opt_acl:
 838                         mnt->flags &= ~NFS_MOUNT_NOACL;
 839                         break;
 840                 case Opt_noacl:
 841                         mnt->flags |= NFS_MOUNT_NOACL;
 842                         break;
 843                 case Opt_rdirplus:
 844                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 845                         break;
 846                 case Opt_nordirplus:
 847                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 848                         break;
 849                 case Opt_sharecache:
 850                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 851                         break;
 852                 case Opt_nosharecache:
 853                         mnt->flags |= NFS_MOUNT_UNSHARED;
 854                         break;
 855
 856                 case Opt_port:
 857                         if (match_int(args, &option))
 858                                 return 0;
 859                         if (option < 0 || option > 65535)
 860                                 return 0;
 861                         mnt->nfs_server.port = option;
 862                         break;
 863                 case Opt_rsize:
 864                         if (match_int(args, &mnt->rsize))
 865                                 return 0;
 866                         break;
 867                 case Opt_wsize:
 868                         if (match_int(args, &mnt->wsize))
 869                                 return 0;
 870                         break;
 871                 case Opt_bsize:
 872                         if (match_int(args, &option))
 873                                 return 0;
 874                         if (option < 0)
 875                                 return 0;
 876                         mnt->bsize = option;
 877                         break;
 878                 case Opt_timeo:
 879                         if (match_int(args, &mnt->timeo))
 880                                 return 0;
 881                         break;
 882                 case Opt_retrans:
 883                         if (match_int(args, &mnt->retrans))
 884                                 return 0;
 885                         break;
 886                 case Opt_acregmin:
 887                         if (match_int(args, &mnt->acregmin))
 888                                 return 0;
 889                         break;
 890                 case Opt_acregmax:
 891                         if (match_int(args, &mnt->acregmax))
 892                                 return 0;
 893                         break;
 894                 case Opt_acdirmin:
 895                         if (match_int(args, &mnt->acdirmin))
 896                                 return 0;
 897                         break;
 898                 case Opt_acdirmax:
 899                         if (match_int(args, &mnt->acdirmax))
 900                                 return 0;
 901                         break;
 902                 case Opt_actimeo:
 903                         if (match_int(args, &option))
 904                                 return 0;
 905                         if (option < 0)
 906                                 return 0;
 907                         mnt->acregmin =
 908                         mnt->acregmax =
 909                         mnt->acdirmin =
 910                         mnt->acdirmax = option;
 911                         break;
 912                 case Opt_namelen:
 913                         if (match_int(args, &mnt->namlen))
 914                                 return 0;
 915                         break;
 916                 case Opt_mountport:
 917                         if (match_int(args, &option))
 918                                 return 0;
 919                         if (option < 0 || option > 65535)
 920                                 return 0;
 921                         mnt->mount_server.port = option;
 922                         break;
 923                 case Opt_mountvers:
 924                         if (match_int(args, &option))
 925                                 return 0;
 926                         if (option < 0)
 927                                 return 0;
 928                         mnt->mount_server.version = option;
 929                         break;
 930                 case Opt_nfsvers:
 931                         if (match_int(args, &option))
 932                                 return 0;
 933                         switch (option) {
 934                         case 2:
 935                                 mnt->flags &= ~NFS_MOUNT_VER3;
 936                                 break;
 937                         case 3:
 938                                 mnt->flags |= NFS_MOUNT_VER3;
 939                                 break;
 940                         default:
 941                                 goto out_unrec_vers;
 942                         }
 943                         break;
 944
 945                 case Opt_sec:
 946                         string = match_strdup(args);
 947                         if (string == NULL)
 948                                 goto out_nomem;
 949                         token = match_token(string, nfs_secflavor_tokens, args);
 950                         kfree(string);
 951
 952                         /*
 953                          * The flags setting is for v2/v3.  The flavor_len
 954                          * setting is for v4.  v2/v3 also need to know the
 955                          * difference between NULL and UNIX.
 956                          */
 957                         switch (token) {
 958                         case Opt_sec_none:
 959                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 960                                 mnt->auth_flavor_len = 0;
 961                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 962                                 break;
 963                         case Opt_sec_sys:
 964                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 965                                 mnt->auth_flavor_len = 0;
 966                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 967                                 break;
 968                         case Opt_sec_krb5:
 969                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 970                                 mnt->auth_flavor_len = 1;
 971                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 972                                 break;
 973                         case Opt_sec_krb5i:
 974                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 975                                 mnt->auth_flavor_len = 1;
 976                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 977                                 break;
 978                         case Opt_sec_krb5p:
 979                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 980                                 mnt->auth_flavor_len = 1;
 981                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 982                                 break;
 983                         case Opt_sec_lkey:
 984                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 985                                 mnt->auth_flavor_len = 1;
 986                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 987                                 break;
 988                         case Opt_sec_lkeyi:
 989                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 990                                 mnt->auth_flavor_len = 1;
 991                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 992                                 break;
 993                         case Opt_sec_lkeyp:
 994                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 995                                 mnt->auth_flavor_len = 1;
 996                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 997                                 break;
 998                         case Opt_sec_spkm:
 999                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1000                                 mnt->auth_flavor_len = 1;
1001                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1002                                 break;
1003                         case Opt_sec_spkmi:
1004                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1005                                 mnt->auth_flavor_len = 1;
1006                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1007                                 break;
1008                         case Opt_sec_spkmp:
1009                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1010                                 mnt->auth_flavor_len = 1;
1011                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1012                                 break;
1013                         default:
1014                                 goto out_unrec_sec;
1015                         }
1016                         break;
1017                 case Opt_proto:
1018                         string = match_strdup(args);
1019                         if (string == NULL)
1020                                 goto out_nomem;
1021                         token = match_token(string,
1022                                             nfs_xprt_protocol_tokens, args);
1023                         kfree(string);
1024
1025                         switch (token) {
1026                         case Opt_xprt_udp:
1027                                 mnt->flags &= ~NFS_MOUNT_TCP;
1028                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1029                                 mnt->timeo = 7;
1030                                 mnt->retrans = 5;
1031                                 break;
1032                         case Opt_xprt_tcp:
1033                                 mnt->flags |= NFS_MOUNT_TCP;
1034                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1035                                 mnt->timeo = 600;
1036                                 mnt->retrans = 2;
1037                                 break;
1038                         case Opt_xprt_rdma:
1039                                 /* vector side protocols to TCP */
1040                                 mnt->flags |= NFS_MOUNT_TCP;
1041                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1042                                 mnt->timeo = 600;
1043                                 mnt->retrans = 2;
1044                                 break;
1045                         default:
1046                                 goto out_unrec_xprt;
1047                         }
1048                         break;
1049                 case Opt_mountproto:
1050                         string = match_strdup(args);
1051                         if (string == NULL)
1052                                 goto out_nomem;
1053                         token = match_token(string,
1054                                             nfs_xprt_protocol_tokens, args);
1055                         kfree(string);
1056
1057                         switch (token) {
1058                         case Opt_xprt_udp:
1059                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1060                                 break;
1061                         case Opt_xprt_tcp:
1062                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1063                                 break;
1064                         case Opt_xprt_rdma: /* not used for side protocols */
1065                         default:
1066                                 goto out_unrec_xprt;
1067                         }
1068                         break;
1069                 case Opt_addr:
1070                         string = match_strdup(args);
1071                         if (string == NULL)
1072                                 goto out_nomem;
1073                         nfs_parse_server_address(string, (struct sockaddr *)
1074                                                  &mnt->nfs_server.address,
1075                                                  &mnt->nfs_server.addrlen);
1076                         kfree(string);
1077                         break;
1078                 case Opt_clientaddr:
1079                         string = match_strdup(args);
1080                         if (string == NULL)
1081                                 goto out_nomem;
1082                         kfree(mnt->client_address);
1083                         mnt->client_address = string;
1084                         break;
1085                 case Opt_mounthost:
1086                         string = match_strdup(args);
1087                         if (string == NULL)
1088                                 goto out_nomem;
1089                         kfree(mnt->mount_server.hostname);
1090                         mnt->mount_server.hostname = string;
1091                         break;
1092                 case Opt_mountaddr:
1093                         string = match_strdup(args);
1094                         if (string == NULL)
1095                                 goto out_nomem;
1096                         nfs_parse_server_address(string, (struct sockaddr *)
1097                                                  &mnt->mount_server.address,
1098                                                  &mnt->mount_server.addrlen);
1099                         kfree(string);
1100                         break;
1101
1102                 case Opt_userspace:
1103                 case Opt_deprecated:
1104                         break;
1105
1106                 default:
1107                         goto out_unknown;
1108                 }
1109         }
1110
1111         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
1112                                 mnt->nfs_server.port);
1113
1114         return 1;
1115
1116 out_nomem:
1117         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1118         return 0;
1119 out_security_failure:
1120         free_secdata(secdata);
1121         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1122         return 0;
1123 out_unrec_vers:
1124         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1125         return 0;
1126
1127 out_unrec_xprt:
1128         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1129         return 0;
1130
1131 out_unrec_sec:
1132         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1133         return 0;
1134
1135 out_unknown:
1136         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1137         return 0;
1138 }
1139
1140 /*
1141  * Use the remote server's MOUNT service to request the NFS file handle
1142  * corresponding to the provided path.
1143  */
1144 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1145                          struct nfs_fh *root_fh)
1146 {
1147         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1148         char *hostname;
1149         int status;
1150
1151         if (args->mount_server.version == 0) {
1152                 if (args->flags & NFS_MOUNT_VER3)
1153                         args->mount_server.version = NFS_MNT3_VERSION;
1154                 else
1155                         args->mount_server.version = NFS_MNT_VERSION;
1156         }
1157
1158         if (args->mount_server.hostname)
1159                 hostname = args->mount_server.hostname;
1160         else
1161                 hostname = args->nfs_server.hostname;
1162
1163         /*
1164          * Construct the mount server's address.
1165          */
1166         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1167                 memcpy(sap, &args->nfs_server.address,
1168                        args->nfs_server.addrlen);
1169                 args->mount_server.addrlen = args->nfs_server.addrlen;
1170         }
1171
1172         /*
1173          * autobind will be used if mount_server.port == 0
1174          */
1175         nfs_set_port(sap, args->mount_server.port);
1176
1177         /*
1178          * Now ask the mount server to map our export path
1179          * to a file handle.
1180          */
1181         status = nfs_mount(sap,
1182                            args->mount_server.addrlen,
1183                            hostname,
1184                            args->nfs_server.export_path,
1185                            args->mount_server.version,
1186                            args->mount_server.protocol,
1187                            root_fh);
1188         if (status == 0)
1189                 return 0;
1190
1191         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d",
1192                         hostname, status);
1193         return status;
1194 }
1195
1196 /*
1197  * Validate the NFS2/NFS3 mount data
1198  * - fills in the mount root filehandle
1199  *
1200  * For option strings, user space handles the following behaviors:
1201  *
1202  * + DNS: mapping server host name to IP address ("addr=" option)
1203  *
1204  * + failure mode: how to behave if a mount request can't be handled
1205  *   immediately ("fg/bg" option)
1206  *
1207  * + retry: how often to retry a mount request ("retry=" option)
1208  *
1209  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1210  *   mountproto=tcp after mountproto=udp, and so on
1211  */
1212 static int nfs_validate_mount_data(void *options,
1213                                    struct nfs_parsed_mount_data *args,
1214                                    struct nfs_fh *mntfh,
1215                                    const char *dev_name)
1216 {
1217         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1218
1219         memset(args, 0, sizeof(*args));
1220
1221         if (data == NULL)
1222                 goto out_no_data;
1223
1224         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1225         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1226         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1227         args->timeo             = 600;
1228         args->retrans           = 2;
1229         args->acregmin          = 3;
1230         args->acregmax          = 60;
1231         args->acdirmin          = 30;
1232         args->acdirmax          = 60;
1233         args->mount_server.port = 0;    /* autobind unless user sets port */
1234         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1235         args->nfs_server.port   = 0;    /* autobind unless user sets port */
1236         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1237
1238         switch (data->version) {
1239         case 1:
1240                 data->namlen = 0;
1241         case 2:
1242                 data->bsize = 0;
1243         case 3:
1244                 if (data->flags & NFS_MOUNT_VER3)
1245                         goto out_no_v3;
1246                 data->root.size = NFS2_FHSIZE;
1247                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1248         case 4:
1249                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1250                         goto out_no_sec;
1251         case 5:
1252                 memset(data->context, 0, sizeof(data->context));
1253         case 6:
1254                 if (data->flags & NFS_MOUNT_VER3)
1255                         mntfh->size = data->root.size;
1256                 else
1257                         mntfh->size = NFS2_FHSIZE;
1258
1259                 if (mntfh->size > sizeof(mntfh->data))
1260                         goto out_invalid_fh;
1261
1262                 memcpy(mntfh->data, data->root.data, mntfh->size);
1263                 if (mntfh->size < sizeof(mntfh->data))
1264                         memset(mntfh->data + mntfh->size, 0,
1265                                sizeof(mntfh->data) - mntfh->size);
1266
1267                 /*
1268                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1269                  * can deal with.
1270                  */
1271                 args->flags             = data->flags;
1272                 args->rsize             = data->rsize;
1273                 args->wsize             = data->wsize;
1274                 args->timeo             = data->timeo;
1275                 args->retrans           = data->retrans;
1276                 args->acregmin          = data->acregmin;
1277                 args->acregmax          = data->acregmax;
1278                 args->acdirmin          = data->acdirmin;
1279                 args->acdirmax          = data->acdirmax;
1280
1281                 memcpy(&args->nfs_server.address, &data->addr,
1282                        sizeof(data->addr));
1283                 args->nfs_server.addrlen = sizeof(data->addr);
1284                 if (!nfs_verify_server_address((struct sockaddr *)
1285                                                 &args->nfs_server.address))
1286                         goto out_no_address;
1287
1288                 if (!(data->flags & NFS_MOUNT_TCP))
1289                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1290                 /* N.B. caller will free nfs_server.hostname in all cases */
1291                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1292                 args->namlen            = data->namlen;
1293                 args->bsize             = data->bsize;
1294                 args->auth_flavors[0]   = data->pseudoflavor;
1295                 if (!args->nfs_server.hostname)
1296                         goto out_nomem;
1297
1298                 /*
1299                  * The legacy version 6 binary mount data from userspace has a
1300                  * field used only to transport selinux information into the
1301                  * the kernel.  To continue to support that functionality we
1302                  * have a touch of selinux knowledge here in the NFS code. The
1303                  * userspace code converted context=blah to just blah so we are
1304                  * converting back to the full string selinux understands.
1305                  */
1306                 if (data->context[0]){
1307 #ifdef CONFIG_SECURITY_SELINUX
1308                         int rc;
1309                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1310                         if (!opts_str)
1311                                 return -ENOMEM;
1312                         strcpy(opts_str, "context=");
1313                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1314                         strcat(opts_str, &data->context[0]);
1315                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1316                         kfree(opts_str);
1317                         if (rc)
1318                                 return rc;
1319 #else
1320                         return -EINVAL;
1321 #endif
1322                 }
1323
1324                 break;
1325         default: {
1326                 unsigned int len;
1327                 char *c;
1328                 int status;
1329
1330                 if (nfs_parse_mount_options((char *)options, args) == 0)
1331                         return -EINVAL;
1332
1333                 if (!nfs_verify_server_address((struct sockaddr *)
1334                                                 &args->nfs_server.address))
1335                         goto out_no_address;
1336
1337                 c = strchr(dev_name, ':');
1338                 if (c == NULL)
1339                         return -EINVAL;
1340                 len = c - dev_name;
1341                 /* N.B. caller will free nfs_server.hostname in all cases */
1342                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1343                 if (!args->nfs_server.hostname)
1344                         goto out_nomem;
1345
1346                 c++;
1347                 if (strlen(c) > NFS_MAXPATHLEN)
1348                         return -ENAMETOOLONG;
1349                 args->nfs_server.export_path = c;
1350
1351                 status = nfs_try_mount(args, mntfh);
1352                 if (status)
1353                         return status;
1354
1355                 break;
1356                 }
1357         }
1358
1359         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1360                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1361
1362 #ifndef CONFIG_NFS_V3
1363         if (args->flags & NFS_MOUNT_VER3)
1364                 goto out_v3_not_compiled;
1365 #endif /* !CONFIG_NFS_V3 */
1366
1367         return 0;
1368
1369 out_no_data:
1370         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1371         return -EINVAL;
1372
1373 out_no_v3:
1374         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1375                  data->version);
1376         return -EINVAL;
1377
1378 out_no_sec:
1379         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1380         return -EINVAL;
1381
1382 #ifndef CONFIG_NFS_V3
1383 out_v3_not_compiled:
1384         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1385         return -EPROTONOSUPPORT;
1386 #endif /* !CONFIG_NFS_V3 */
1387
1388 out_nomem:
1389         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1390         return -ENOMEM;
1391
1392 out_no_address:
1393         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1394         return -EINVAL;
1395
1396 out_invalid_fh:
1397         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1398         return -EINVAL;
1399 }
1400
1401 /*
1402  * Initialise the common bits of the superblock
1403  */
1404 static inline void nfs_initialise_sb(struct super_block *sb)
1405 {
1406         struct nfs_server *server = NFS_SB(sb);
1407
1408         sb->s_magic = NFS_SUPER_MAGIC;
1409
1410         /* We probably want something more informative here */
1411         snprintf(sb->s_id, sizeof(sb->s_id),
1412                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1413
1414         if (sb->s_blocksize == 0)
1415                 sb->s_blocksize = nfs_block_bits(server->wsize,
1416                                                  &sb->s_blocksize_bits);
1417
1418         if (server->flags & NFS_MOUNT_NOAC)
1419                 sb->s_flags |= MS_SYNCHRONOUS;
1420
1421         nfs_super_set_maxbytes(sb, server->maxfilesize);
1422 }
1423
1424 /*
1425  * Finish setting up an NFS2/3 superblock
1426  */
1427 static void nfs_fill_super(struct super_block *sb,
1428                            struct nfs_parsed_mount_data *data)
1429 {
1430         struct nfs_server *server = NFS_SB(sb);
1431
1432         sb->s_blocksize_bits = 0;
1433         sb->s_blocksize = 0;
1434         if (data->bsize)
1435                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1436
1437         if (server->flags & NFS_MOUNT_VER3) {
1438                 /* The VFS shouldn't apply the umask to mode bits. We will do
1439                  * so ourselves when necessary.
1440                  */
1441                 sb->s_flags |= MS_POSIXACL;
1442                 sb->s_time_gran = 1;
1443         }
1444
1445         sb->s_op = &nfs_sops;
1446         nfs_initialise_sb(sb);
1447 }
1448
1449 /*
1450  * Finish setting up a cloned NFS2/3 superblock
1451  */
1452 static void nfs_clone_super(struct super_block *sb,
1453                             const struct super_block *old_sb)
1454 {
1455         struct nfs_server *server = NFS_SB(sb);
1456
1457         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1458         sb->s_blocksize = old_sb->s_blocksize;
1459         sb->s_maxbytes = old_sb->s_maxbytes;
1460
1461         if (server->flags & NFS_MOUNT_VER3) {
1462                 /* The VFS shouldn't apply the umask to mode bits. We will do
1463                  * so ourselves when necessary.
1464                  */
1465                 sb->s_flags |= MS_POSIXACL;
1466                 sb->s_time_gran = 1;
1467         }
1468
1469         sb->s_op = old_sb->s_op;
1470         nfs_initialise_sb(sb);
1471 }
1472
1473 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1474
1475 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1476 {
1477         const struct nfs_server *a = s->s_fs_info;
1478         const struct rpc_clnt *clnt_a = a->client;
1479         const struct rpc_clnt *clnt_b = b->client;
1480
1481         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1482                 goto Ebusy;
1483         if (a->nfs_client != b->nfs_client)
1484                 goto Ebusy;
1485         if (a->flags != b->flags)
1486                 goto Ebusy;
1487         if (a->wsize != b->wsize)
1488                 goto Ebusy;
1489         if (a->rsize != b->rsize)
1490                 goto Ebusy;
1491         if (a->acregmin != b->acregmin)
1492                 goto Ebusy;
1493         if (a->acregmax != b->acregmax)
1494                 goto Ebusy;
1495         if (a->acdirmin != b->acdirmin)
1496                 goto Ebusy;
1497         if (a->acdirmax != b->acdirmax)
1498                 goto Ebusy;
1499         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1500                 goto Ebusy;
1501         return 1;
1502 Ebusy:
1503         return 0;
1504 }
1505
1506 struct nfs_sb_mountdata {
1507         struct nfs_server *server;
1508         int mntflags;
1509 };
1510
1511 static int nfs_set_super(struct super_block *s, void *data)
1512 {
1513         struct nfs_sb_mountdata *sb_mntdata = data;
1514         struct nfs_server *server = sb_mntdata->server;
1515         int ret;
1516
1517         s->s_flags = sb_mntdata->mntflags;
1518         s->s_fs_info = server;
1519         ret = set_anon_super(s, server);
1520         if (ret == 0)
1521                 server->s_dev = s->s_dev;
1522         return ret;
1523 }
1524
1525 static int nfs_compare_super_address(struct nfs_server *server1,
1526                                      struct nfs_server *server2)
1527 {
1528         struct sockaddr *sap1, *sap2;
1529
1530         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1531         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1532
1533         if (sap1->sa_family != sap2->sa_family)
1534                 return 0;
1535
1536         switch (sap1->sa_family) {
1537         case AF_INET: {
1538                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1539                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1540                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1541                         return 0;
1542                 if (sin1->sin_port != sin2->sin_port)
1543                         return 0;
1544                 break;
1545         }
1546         case AF_INET6: {
1547                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1548                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1549                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1550                         return 0;
1551                 if (sin1->sin6_port != sin2->sin6_port)
1552                         return 0;
1553                 break;
1554         }
1555         default:
1556                 return 0;
1557         }
1558
1559         return 1;
1560 }
1561
1562 static int nfs_compare_super(struct super_block *sb, void *data)
1563 {
1564         struct nfs_sb_mountdata *sb_mntdata = data;
1565         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1566         int mntflags = sb_mntdata->mntflags;
1567
1568         if (!nfs_compare_super_address(old, server))
1569                 return 0;
1570         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1571         if (old->flags & NFS_MOUNT_UNSHARED)
1572                 return 0;
1573         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1574                 return 0;
1575         return nfs_compare_mount_options(sb, server, mntflags);
1576 }
1577
1578 static int nfs_get_sb(struct file_system_type *fs_type,
1579         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1580 {
1581         struct nfs_server *server = NULL;
1582         struct super_block *s;
1583         struct nfs_fh mntfh;
1584         struct nfs_parsed_mount_data data;
1585         struct dentry *mntroot;
1586         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1587         struct nfs_sb_mountdata sb_mntdata = {
1588                 .mntflags = flags,
1589         };
1590         int error;
1591
1592         security_init_mnt_opts(&data.lsm_opts);
1593
1594         /* Validate the mount data */
1595         error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);
1596         if (error < 0)
1597                 goto out;
1598
1599         /* Get a volume representation */
1600         server = nfs_create_server(&data, &mntfh);
1601         if (IS_ERR(server)) {
1602                 error = PTR_ERR(server);
1603                 goto out;
1604         }
1605         sb_mntdata.server = server;
1606
1607         if (server->flags & NFS_MOUNT_UNSHARED)
1608                 compare_super = NULL;
1609
1610         /* Get a superblock - note that we may end up sharing one that already exists */
1611         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1612         if (IS_ERR(s)) {
1613                 error = PTR_ERR(s);
1614                 goto out_err_nosb;
1615         }
1616
1617         if (s->s_fs_info != server) {
1618                 nfs_free_server(server);
1619                 server = NULL;
1620         }
1621
1622         if (!s->s_root) {
1623                 /* initial superblock/root creation */
1624                 nfs_fill_super(s, &data);
1625         }
1626
1627         mntroot = nfs_get_root(s, &mntfh);
1628         if (IS_ERR(mntroot)) {
1629                 error = PTR_ERR(mntroot);
1630                 goto error_splat_super;
1631         }
1632
1633         error = security_sb_set_mnt_opts(s, &data.lsm_opts);
1634         if (error)
1635                 goto error_splat_root;
1636
1637         s->s_flags |= MS_ACTIVE;
1638         mnt->mnt_sb = s;
1639         mnt->mnt_root = mntroot;
1640         error = 0;
1641
1642 out:
1643         kfree(data.nfs_server.hostname);
1644         kfree(data.mount_server.hostname);
1645         security_free_mnt_opts(&data.lsm_opts);
1646         return error;
1647
1648 out_err_nosb:
1649         nfs_free_server(server);
1650         goto out;
1651
1652 error_splat_root:
1653         dput(mntroot);
1654 error_splat_super:
1655         up_write(&s->s_umount);
1656         deactivate_super(s);
1657         goto out;
1658 }
1659
1660 /*
1661  * Destroy an NFS2/3 superblock
1662  */
1663 static void nfs_kill_super(struct super_block *s)
1664 {
1665         struct nfs_server *server = NFS_SB(s);
1666
1667         kill_anon_super(s);
1668         nfs_free_server(server);
1669 }
1670
1671 /*
1672  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1673  */
1674 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1675                            const char *dev_name, void *raw_data,
1676                            struct vfsmount *mnt)
1677 {
1678         struct nfs_clone_mount *data = raw_data;
1679         struct super_block *s;
1680         struct nfs_server *server;
1681         struct dentry *mntroot;
1682         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1683         struct nfs_sb_mountdata sb_mntdata = {
1684                 .mntflags = flags,
1685         };
1686         int error;
1687
1688         dprintk("--> nfs_xdev_get_sb()\n");
1689
1690         /* create a new volume representation */
1691         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1692         if (IS_ERR(server)) {
1693                 error = PTR_ERR(server);
1694                 goto out_err_noserver;
1695         }
1696         sb_mntdata.server = server;
1697
1698         if (server->flags & NFS_MOUNT_UNSHARED)
1699                 compare_super = NULL;
1700
1701         /* Get a superblock - note that we may end up sharing one that already exists */
1702         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1703         if (IS_ERR(s)) {
1704                 error = PTR_ERR(s);
1705                 goto out_err_nosb;
1706         }
1707
1708         if (s->s_fs_info != server) {
1709                 nfs_free_server(server);
1710                 server = NULL;
1711         }
1712
1713         if (!s->s_root) {
1714                 /* initial superblock/root creation */
1715                 nfs_clone_super(s, data->sb);
1716         }
1717
1718         mntroot = nfs_get_root(s, data->fh);
1719         if (IS_ERR(mntroot)) {
1720                 error = PTR_ERR(mntroot);
1721                 goto error_splat_super;
1722         }
1723         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1724                 dput(mntroot);
1725                 error = -ESTALE;
1726                 goto error_splat_super;
1727         }
1728
1729         s->s_flags |= MS_ACTIVE;
1730         mnt->mnt_sb = s;
1731         mnt->mnt_root = mntroot;
1732
1733         /* clone any lsm security options from the parent to the new sb */
1734         security_sb_clone_mnt_opts(data->sb, s);
1735
1736         dprintk("<-- nfs_xdev_get_sb() = 0\n");
1737         return 0;
1738
1739 out_err_nosb:
1740         nfs_free_server(server);
1741 out_err_noserver:
1742         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
1743         return error;
1744
1745 error_splat_super:
1746         up_write(&s->s_umount);
1747         deactivate_super(s);
1748         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
1749         return error;
1750 }
1751
1752 #ifdef CONFIG_NFS_V4
1753
1754 /*
1755  * Finish setting up a cloned NFS4 superblock
1756  */
1757 static void nfs4_clone_super(struct super_block *sb,
1758                             const struct super_block *old_sb)
1759 {
1760         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1761         sb->s_blocksize = old_sb->s_blocksize;
1762         sb->s_maxbytes = old_sb->s_maxbytes;
1763         sb->s_time_gran = 1;
1764         sb->s_op = old_sb->s_op;
1765         nfs_initialise_sb(sb);
1766 }
1767
1768 /*
1769  * Set up an NFS4 superblock
1770  */
1771 static void nfs4_fill_super(struct super_block *sb)
1772 {
1773         sb->s_time_gran = 1;
1774         sb->s_op = &nfs4_sops;
1775         nfs_initialise_sb(sb);
1776 }
1777
1778 /*
1779  * Validate NFSv4 mount options
1780  */
1781 static int nfs4_validate_mount_data(void *options,
1782                                     struct nfs_parsed_mount_data *args,
1783                                     const char *dev_name)
1784 {
1785         struct sockaddr_in *ap;
1786         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
1787         char *c;
1788
1789         memset(args, 0, sizeof(*args));
1790
1791         if (data == NULL)
1792                 goto out_no_data;
1793
1794         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1795         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1796         args->timeo             = 600;
1797         args->retrans           = 2;
1798         args->acregmin          = 3;
1799         args->acregmax          = 60;
1800         args->acdirmin          = 30;
1801         args->acdirmax          = 60;
1802         args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
1803         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1804
1805         switch (data->version) {
1806         case 1:
1807                 ap = (struct sockaddr_in *)&args->nfs_server.address;
1808                 if (data->host_addrlen > sizeof(args->nfs_server.address))
1809                         goto out_no_address;
1810                 if (data->host_addrlen == 0)
1811                         goto out_no_address;
1812                 args->nfs_server.addrlen = data->host_addrlen;
1813                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
1814                         return -EFAULT;
1815                 if (!nfs_verify_server_address((struct sockaddr *)
1816                                                 &args->nfs_server.address))
1817                         goto out_no_address;
1818
1819                 switch (data->auth_flavourlen) {
1820                 case 0:
1821                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1822                         break;
1823                 case 1:
1824                         if (copy_from_user(&args->auth_flavors[0],
1825                                            data->auth_flavours,
1826                                            sizeof(args->auth_flavors[0])))
1827                                 return -EFAULT;
1828                         break;
1829                 default:
1830                         goto out_inval_auth;
1831                 }
1832
1833                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1834                 if (IS_ERR(c))
1835                         return PTR_ERR(c);
1836                 args->nfs_server.hostname = c;
1837
1838                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1839                 if (IS_ERR(c))
1840                         return PTR_ERR(c);
1841                 args->nfs_server.export_path = c;
1842                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1843
1844                 c = strndup_user(data->client_addr.data, 16);
1845                 if (IS_ERR(c))
1846                         return PTR_ERR(c);
1847                 args->client_address = c;
1848
1849                 /*
1850                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
1851                  * can deal with.
1852                  */
1853
1854                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
1855                 args->rsize     = data->rsize;
1856                 args->wsize     = data->wsize;
1857                 args->timeo     = data->timeo;
1858                 args->retrans   = data->retrans;
1859                 args->acregmin  = data->acregmin;
1860                 args->acregmax  = data->acregmax;
1861                 args->acdirmin  = data->acdirmin;
1862                 args->acdirmax  = data->acdirmax;
1863                 args->nfs_server.protocol = data->proto;
1864
1865                 break;
1866         default: {
1867                 unsigned int len;
1868
1869                 if (nfs_parse_mount_options((char *)options, args) == 0)
1870                         return -EINVAL;
1871
1872                 if (!nfs_verify_server_address((struct sockaddr *)
1873                                                 &args->nfs_server.address))
1874                         return -EINVAL;
1875
1876                 switch (args->auth_flavor_len) {
1877                 case 0:
1878                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1879                         break;
1880                 case 1:
1881                         break;
1882                 default:
1883                         goto out_inval_auth;
1884                 }
1885
1886                 /*
1887                  * Split "dev_name" into "hostname:mntpath".
1888                  */
1889                 c = strchr(dev_name, ':');
1890                 if (c == NULL)
1891                         return -EINVAL;
1892                 /* while calculating len, pretend ':' is '\0' */
1893                 len = c - dev_name;
1894                 if (len > NFS4_MAXNAMLEN)
1895                         return -ENAMETOOLONG;
1896                 /* N.B. caller will free nfs_server.hostname in all cases */
1897                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1898                 if (!args->nfs_server.hostname)
1899                         goto out_nomem;
1900
1901                 c++;                    /* step over the ':' */
1902                 len = strlen(c);
1903                 if (len > NFS4_MAXPATHLEN)
1904                         return -ENAMETOOLONG;
1905                 args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
1906                 if (!args->nfs_server.export_path)
1907                         goto out_nomem;
1908
1909                 dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);
1910
1911                 if (args->client_address == NULL)
1912                         goto out_no_client_address;
1913
1914                 break;
1915                 }
1916         }
1917
1918         return 0;
1919
1920 out_no_data:
1921         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
1922         return -EINVAL;
1923
1924 out_inval_auth:
1925         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
1926                  data->auth_flavourlen);
1927         return -EINVAL;
1928
1929 out_nomem:
1930         dfprintk(MOUNT, "NFS4: not enough memory to handle mount options\n");
1931         return -ENOMEM;
1932
1933 out_no_address:
1934         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
1935         return -EINVAL;
1936
1937 out_no_client_address:
1938         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
1939         return -EINVAL;
1940 }
1941
1942 /*
1943  * Get the superblock for an NFS4 mountpoint
1944  */
1945 static int nfs4_get_sb(struct file_system_type *fs_type,
1946         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1947 {
1948         struct nfs_parsed_mount_data data;
1949         struct super_block *s;
1950         struct nfs_server *server;
1951         struct nfs_fh mntfh;
1952         struct dentry *mntroot;
1953         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1954         struct nfs_sb_mountdata sb_mntdata = {
1955                 .mntflags = flags,
1956         };
1957         int error;
1958
1959         security_init_mnt_opts(&data.lsm_opts);
1960
1961         /* Validate the mount data */
1962         error = nfs4_validate_mount_data(raw_data, &data, dev_name);
1963         if (error < 0)
1964                 goto out;
1965
1966         /* Get a volume representation */
1967         server = nfs4_create_server(&data, &mntfh);
1968         if (IS_ERR(server)) {
1969                 error = PTR_ERR(server);
1970                 goto out;
1971         }
1972         sb_mntdata.server = server;
1973
1974         if (server->flags & NFS4_MOUNT_UNSHARED)
1975                 compare_super = NULL;
1976
1977         /* Get a superblock - note that we may end up sharing one that already exists */
1978         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1979         if (IS_ERR(s)) {
1980                 error = PTR_ERR(s);
1981                 goto out_free;
1982         }
1983
1984         if (s->s_fs_info != server) {
1985                 nfs_free_server(server);
1986                 server = NULL;
1987         }
1988
1989         if (!s->s_root) {
1990                 /* initial superblock/root creation */
1991                 nfs4_fill_super(s);
1992         }
1993
1994         mntroot = nfs4_get_root(s, &mntfh);
1995         if (IS_ERR(mntroot)) {
1996                 error = PTR_ERR(mntroot);
1997                 goto error_splat_super;
1998         }
1999
2000         s->s_flags |= MS_ACTIVE;
2001         mnt->mnt_sb = s;
2002         mnt->mnt_root = mntroot;
2003         error = 0;
2004
2005 out:
2006         kfree(data.client_address);
2007         kfree(data.nfs_server.export_path);
2008         kfree(data.nfs_server.hostname);
2009         security_free_mnt_opts(&data.lsm_opts);
2010         return error;
2011
2012 out_free:
2013         nfs_free_server(server);
2014         goto out;
2015
2016 error_splat_super:
2017         up_write(&s->s_umount);
2018         deactivate_super(s);
2019         goto out;
2020 }
2021
2022 static void nfs4_kill_super(struct super_block *sb)
2023 {
2024         struct nfs_server *server = NFS_SB(sb);
2025
2026         nfs_return_all_delegations(sb);
2027         kill_anon_super(sb);
2028
2029         nfs4_renewd_prepare_shutdown(server);
2030         nfs_free_server(server);
2031 }
2032
2033 /*
2034  * Clone an NFS4 server record on xdev traversal (FSID-change)
2035  */
2036 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2037                             const char *dev_name, void *raw_data,
2038                             struct vfsmount *mnt)
2039 {
2040         struct nfs_clone_mount *data = raw_data;
2041         struct super_block *s;
2042         struct nfs_server *server;
2043         struct dentry *mntroot;
2044         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2045         struct nfs_sb_mountdata sb_mntdata = {
2046                 .mntflags = flags,
2047         };
2048         int error;
2049
2050         dprintk("--> nfs4_xdev_get_sb()\n");
2051
2052         /* create a new volume representation */
2053         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2054         if (IS_ERR(server)) {
2055                 error = PTR_ERR(server);
2056                 goto out_err_noserver;
2057         }
2058         sb_mntdata.server = server;
2059
2060         if (server->flags & NFS4_MOUNT_UNSHARED)
2061                 compare_super = NULL;
2062
2063         /* Get a superblock - note that we may end up sharing one that already exists */
2064         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2065         if (IS_ERR(s)) {
2066                 error = PTR_ERR(s);
2067                 goto out_err_nosb;
2068         }
2069
2070         if (s->s_fs_info != server) {
2071                 nfs_free_server(server);
2072                 server = NULL;
2073         }
2074
2075         if (!s->s_root) {
2076                 /* initial superblock/root creation */
2077                 nfs4_clone_super(s, data->sb);
2078         }
2079
2080         mntroot = nfs4_get_root(s, data->fh);
2081         if (IS_ERR(mntroot)) {
2082                 error = PTR_ERR(mntroot);
2083                 goto error_splat_super;
2084         }
2085         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2086                 dput(mntroot);
2087                 error = -ESTALE;
2088                 goto error_splat_super;
2089         }
2090
2091         s->s_flags |= MS_ACTIVE;
2092         mnt->mnt_sb = s;
2093         mnt->mnt_root = mntroot;
2094
2095         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2096         return 0;
2097
2098 out_err_nosb:
2099         nfs_free_server(server);
2100 out_err_noserver:
2101         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2102         return error;
2103
2104 error_splat_super:
2105         up_write(&s->s_umount);
2106         deactivate_super(s);
2107         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2108         return error;
2109 }
2110
2111 /*
2112  * Create an NFS4 server record on referral traversal
2113  */
2114 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2115                                 const char *dev_name, void *raw_data,
2116                                 struct vfsmount *mnt)
2117 {
2118         struct nfs_clone_mount *data = raw_data;
2119         struct super_block *s;
2120         struct nfs_server *server;
2121         struct dentry *mntroot;
2122         struct nfs_fh mntfh;
2123         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2124         struct nfs_sb_mountdata sb_mntdata = {
2125                 .mntflags = flags,
2126         };
2127         int error;
2128
2129         dprintk("--> nfs4_referral_get_sb()\n");
2130
2131         /* create a new volume representation */
2132         server = nfs4_create_referral_server(data, &mntfh);
2133         if (IS_ERR(server)) {
2134                 error = PTR_ERR(server);
2135                 goto out_err_noserver;
2136         }
2137         sb_mntdata.server = server;
2138
2139         if (server->flags & NFS4_MOUNT_UNSHARED)
2140                 compare_super = NULL;
2141
2142         /* Get a superblock - note that we may end up sharing one that already exists */
2143         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2144         if (IS_ERR(s)) {
2145                 error = PTR_ERR(s);
2146                 goto out_err_nosb;
2147         }
2148
2149         if (s->s_fs_info != server) {
2150                 nfs_free_server(server);
2151                 server = NULL;
2152         }
2153
2154         if (!s->s_root) {
2155                 /* initial superblock/root creation */
2156                 nfs4_fill_super(s);
2157         }
2158
2159         mntroot = nfs4_get_root(s, &mntfh);
2160         if (IS_ERR(mntroot)) {
2161                 error = PTR_ERR(mntroot);
2162                 goto error_splat_super;
2163         }
2164         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2165                 dput(mntroot);
2166                 error = -ESTALE;
2167                 goto error_splat_super;
2168         }
2169
2170         s->s_flags |= MS_ACTIVE;
2171         mnt->mnt_sb = s;
2172         mnt->mnt_root = mntroot;
2173
2174         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2175         return 0;
2176
2177 out_err_nosb:
2178         nfs_free_server(server);
2179 out_err_noserver:
2180         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2181         return error;
2182
2183 error_splat_super:
2184         up_write(&s->s_umount);
2185         deactivate_super(s);
2186         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2187         return error;
2188 }
2189
2190 #endif /* CONFIG_NFS_V4 */