fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/smp_lock.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <net/ipv6.h>
  50 #include <linux/nfs_xdr.h>
  51 #include <linux/magic.h>
  52 #include <linux/parser.h>
  53
  54 #include <asm/system.h>
  55 #include <asm/uaccess.h>
  56
  57 #include "nfs4_fs.h"
  58 #include "callback.h"
  59 #include "delegation.h"
  60 #include "iostat.h"
  61 #include "internal.h"
  62
  63 #define NFSDBG_FACILITY         NFSDBG_VFS
  64
  65 enum {
  66         /* Mount options that take no arguments */
  67         Opt_soft, Opt_hard,
  68         Opt_posix, Opt_noposix,
  69         Opt_cto, Opt_nocto,
  70         Opt_ac, Opt_noac,
  71         Opt_lock, Opt_nolock,
  72         Opt_v2, Opt_v3,
  73         Opt_udp, Opt_tcp, Opt_rdma,
  74         Opt_acl, Opt_noacl,
  75         Opt_rdirplus, Opt_nordirplus,
  76         Opt_sharecache, Opt_nosharecache,
  77
  78         /* Mount options that take integer arguments */
  79         Opt_port,
  80         Opt_rsize, Opt_wsize, Opt_bsize,
  81         Opt_timeo, Opt_retrans,
  82         Opt_acregmin, Opt_acregmax,
  83         Opt_acdirmin, Opt_acdirmax,
  84         Opt_actimeo,
  85         Opt_namelen,
  86         Opt_mountport,
  87         Opt_mountvers,
  88         Opt_nfsvers,
  89
  90         /* Mount options that take string arguments */
  91         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
  92         Opt_addr, Opt_mountaddr, Opt_clientaddr,
  93
  94         /* Mount options that are ignored */
  95         Opt_userspace, Opt_deprecated,
  96
  97         Opt_err
  98 };
  99
 100 static match_table_t nfs_mount_option_tokens = {
 101         { Opt_userspace, "bg" },
 102         { Opt_userspace, "fg" },
 103         { Opt_userspace, "retry=%s" },
 104
 105         { Opt_soft, "soft" },
 106         { Opt_hard, "hard" },
 107         { Opt_deprecated, "intr" },
 108         { Opt_deprecated, "nointr" },
 109         { Opt_posix, "posix" },
 110         { Opt_noposix, "noposix" },
 111         { Opt_cto, "cto" },
 112         { Opt_nocto, "nocto" },
 113         { Opt_ac, "ac" },
 114         { Opt_noac, "noac" },
 115         { Opt_lock, "lock" },
 116         { Opt_nolock, "nolock" },
 117         { Opt_v2, "v2" },
 118         { Opt_v3, "v3" },
 119         { Opt_udp, "udp" },
 120         { Opt_tcp, "tcp" },
 121         { Opt_rdma, "rdma" },
 122         { Opt_acl, "acl" },
 123         { Opt_noacl, "noacl" },
 124         { Opt_rdirplus, "rdirplus" },
 125         { Opt_nordirplus, "nordirplus" },
 126         { Opt_sharecache, "sharecache" },
 127         { Opt_nosharecache, "nosharecache" },
 128
 129         { Opt_port, "port=%u" },
 130         { Opt_rsize, "rsize=%u" },
 131         { Opt_wsize, "wsize=%u" },
 132         { Opt_bsize, "bsize=%u" },
 133         { Opt_timeo, "timeo=%u" },
 134         { Opt_retrans, "retrans=%u" },
 135         { Opt_acregmin, "acregmin=%u" },
 136         { Opt_acregmax, "acregmax=%u" },
 137         { Opt_acdirmin, "acdirmin=%u" },
 138         { Opt_acdirmax, "acdirmax=%u" },
 139         { Opt_actimeo, "actimeo=%u" },
 140         { Opt_namelen, "namlen=%u" },
 141         { Opt_mountport, "mountport=%u" },
 142         { Opt_mountvers, "mountvers=%u" },
 143         { Opt_nfsvers, "nfsvers=%u" },
 144         { Opt_nfsvers, "vers=%u" },
 145
 146         { Opt_sec, "sec=%s" },
 147         { Opt_proto, "proto=%s" },
 148         { Opt_mountproto, "mountproto=%s" },
 149         { Opt_addr, "addr=%s" },
 150         { Opt_clientaddr, "clientaddr=%s" },
 151         { Opt_mounthost, "mounthost=%s" },
 152         { Opt_mountaddr, "mountaddr=%s" },
 153
 154         { Opt_err, NULL }
 155 };
 156
 157 enum {
 158         Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
 159
 160         Opt_xprt_err
 161 };
 162
 163 static match_table_t nfs_xprt_protocol_tokens = {
 164         { Opt_xprt_udp, "udp" },
 165         { Opt_xprt_tcp, "tcp" },
 166         { Opt_xprt_rdma, "rdma" },
 167
 168         { Opt_xprt_err, NULL }
 169 };
 170
 171 enum {
 172         Opt_sec_none, Opt_sec_sys,
 173         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 174         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 175         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 176
 177         Opt_sec_err
 178 };
 179
 180 static match_table_t nfs_secflavor_tokens = {
 181         { Opt_sec_none, "none" },
 182         { Opt_sec_none, "null" },
 183         { Opt_sec_sys, "sys" },
 184
 185         { Opt_sec_krb5, "krb5" },
 186         { Opt_sec_krb5i, "krb5i" },
 187         { Opt_sec_krb5p, "krb5p" },
 188
 189         { Opt_sec_lkey, "lkey" },
 190         { Opt_sec_lkeyi, "lkeyi" },
 191         { Opt_sec_lkeyp, "lkeyp" },
 192
 193         { Opt_sec_spkm, "spkm3" },
 194         { Opt_sec_spkmi, "spkm3i" },
 195         { Opt_sec_spkmp, "spkm3p" },
 196
 197         { Opt_sec_err, NULL }
 198 };
 199
 200
 201 static void nfs_umount_begin(struct super_block *);
 202 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 203 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 204 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 205 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 206 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 207                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 208 static void nfs_kill_super(struct super_block *);
 209 static void nfs_put_super(struct super_block *);
 210 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 211
 212 static struct file_system_type nfs_fs_type = {
 213         .owner          = THIS_MODULE,
 214         .name           = "nfs",
 215         .get_sb         = nfs_get_sb,
 216         .kill_sb        = nfs_kill_super,
 217         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 218 };
 219
 220 struct file_system_type nfs_xdev_fs_type = {
 221         .owner          = THIS_MODULE,
 222         .name           = "nfs",
 223         .get_sb         = nfs_xdev_get_sb,
 224         .kill_sb        = nfs_kill_super,
 225         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 226 };
 227
 228 static const struct super_operations nfs_sops = {
 229         .alloc_inode    = nfs_alloc_inode,
 230         .destroy_inode  = nfs_destroy_inode,
 231         .write_inode    = nfs_write_inode,
 232         .put_super      = nfs_put_super,
 233         .statfs         = nfs_statfs,
 234         .clear_inode    = nfs_clear_inode,
 235         .umount_begin   = nfs_umount_begin,
 236         .show_options   = nfs_show_options,
 237         .show_stats     = nfs_show_stats,
 238         .remount_fs     = nfs_remount,
 239 };
 240
 241 #ifdef CONFIG_NFS_V4
 242 static int nfs4_get_sb(struct file_system_type *fs_type,
 243         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 244 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 245         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 246 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 247         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 248 static void nfs4_kill_super(struct super_block *sb);
 249
 250 static struct file_system_type nfs4_fs_type = {
 251         .owner          = THIS_MODULE,
 252         .name           = "nfs4",
 253         .get_sb         = nfs4_get_sb,
 254         .kill_sb        = nfs4_kill_super,
 255         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 256 };
 257
 258 struct file_system_type nfs4_xdev_fs_type = {
 259         .owner          = THIS_MODULE,
 260         .name           = "nfs4",
 261         .get_sb         = nfs4_xdev_get_sb,
 262         .kill_sb        = nfs4_kill_super,
 263         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 264 };
 265
 266 struct file_system_type nfs4_referral_fs_type = {
 267         .owner          = THIS_MODULE,
 268         .name           = "nfs4",
 269         .get_sb         = nfs4_referral_get_sb,
 270         .kill_sb        = nfs4_kill_super,
 271         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 272 };
 273
 274 static const struct super_operations nfs4_sops = {
 275         .alloc_inode    = nfs_alloc_inode,
 276         .destroy_inode  = nfs_destroy_inode,
 277         .write_inode    = nfs_write_inode,
 278         .statfs         = nfs_statfs,
 279         .clear_inode    = nfs4_clear_inode,
 280         .umount_begin   = nfs_umount_begin,
 281         .show_options   = nfs_show_options,
 282         .show_stats     = nfs_show_stats,
 283         .remount_fs     = nfs_remount,
 284 };
 285 #endif
 286
 287 static struct shrinker acl_shrinker = {
 288         .shrink         = nfs_access_cache_shrinker,
 289         .seeks          = DEFAULT_SEEKS,
 290 };
 291
 292 /*
 293  * Register the NFS filesystems
 294  */
 295 int __init register_nfs_fs(void)
 296 {
 297         int ret;
 298
 299         ret = register_filesystem(&nfs_fs_type);
 300         if (ret < 0)
 301                 goto error_0;
 302
 303         ret = nfs_register_sysctl();
 304         if (ret < 0)
 305                 goto error_1;
 306 #ifdef CONFIG_NFS_V4
 307         ret = register_filesystem(&nfs4_fs_type);
 308         if (ret < 0)
 309                 goto error_2;
 310 #endif
 311         register_shrinker(&acl_shrinker);
 312         return 0;
 313
 314 #ifdef CONFIG_NFS_V4
 315 error_2:
 316         nfs_unregister_sysctl();
 317 #endif
 318 error_1:
 319         unregister_filesystem(&nfs_fs_type);
 320 error_0:
 321         return ret;
 322 }
 323
 324 /*
 325  * Unregister the NFS filesystems
 326  */
 327 void __exit unregister_nfs_fs(void)
 328 {
 329         unregister_shrinker(&acl_shrinker);
 330 #ifdef CONFIG_NFS_V4
 331         unregister_filesystem(&nfs4_fs_type);
 332 #endif
 333         nfs_unregister_sysctl();
 334         unregister_filesystem(&nfs_fs_type);
 335 }
 336
 337 void nfs_sb_active(struct nfs_server *server)
 338 {
 339         atomic_inc(&server->active);
 340 }
 341
 342 void nfs_sb_deactive(struct nfs_server *server)
 343 {
 344         if (atomic_dec_and_test(&server->active))
 345                 wake_up(&server->active_wq);
 346 }
 347
 348 static void nfs_put_super(struct super_block *sb)
 349 {
 350         struct nfs_server *server = NFS_SB(sb);
 351         /*
 352          * Make sure there are no outstanding ops to this server.
 353          * If so, wait for them to finish before allowing the
 354          * unmount to continue.
 355          */
 356         wait_event(server->active_wq, atomic_read(&server->active) == 0);
 357 }
 358
 359 /*
 360  * Deliver file system statistics to userspace
 361  */
 362 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 363 {
 364         struct nfs_server *server = NFS_SB(dentry->d_sb);
 365         unsigned char blockbits;
 366         unsigned long blockres;
 367         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 368         struct nfs_fattr fattr;
 369         struct nfs_fsstat res = {
 370                         .fattr = &fattr,
 371         };
 372         int error;
 373
 374         lock_kernel();
 375
 376         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 377         if (error < 0)
 378                 goto out_err;
 379         buf->f_type = NFS_SUPER_MAGIC;
 380
 381         /*
 382          * Current versions of glibc do not correctly handle the
 383          * case where f_frsize != f_bsize.  Eventually we want to
 384          * report the value of wtmult in this field.
 385          */
 386         buf->f_frsize = dentry->d_sb->s_blocksize;
 387
 388         /*
 389          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 390          * are reported in units of f_frsize.  Linux hasn't had
 391          * an f_frsize field in its statfs struct until recently,
 392          * thus historically Linux's sys_statfs reports these
 393          * fields in units of f_bsize.
 394          */
 395         buf->f_bsize = dentry->d_sb->s_blocksize;
 396         blockbits = dentry->d_sb->s_blocksize_bits;
 397         blockres = (1 << blockbits) - 1;
 398         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 399         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 400         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 401
 402         buf->f_files = res.tfiles;
 403         buf->f_ffree = res.afiles;
 404
 405         buf->f_namelen = server->namelen;
 406
 407         unlock_kernel();
 408         return 0;
 409
 410  out_err:
 411         dprintk("%s: statfs error = %d\n", __func__, -error);
 412         unlock_kernel();
 413         return error;
 414 }
 415
 416 /*
 417  * Map the security flavour number to a name
 418  */
 419 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 420 {
 421         static const struct {
 422                 rpc_authflavor_t flavour;
 423                 const char *str;
 424         } sec_flavours[] = {
 425                 { RPC_AUTH_NULL, "null" },
 426                 { RPC_AUTH_UNIX, "sys" },
 427                 { RPC_AUTH_GSS_KRB5, "krb5" },
 428                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 429                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 430                 { RPC_AUTH_GSS_LKEY, "lkey" },
 431                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 432                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 433                 { RPC_AUTH_GSS_SPKM, "spkm" },
 434                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 435                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 436                 { UINT_MAX, "unknown" }
 437         };
 438         int i;
 439
 440         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 441                 if (sec_flavours[i].flavour == flavour)
 442                         break;
 443         }
 444         return sec_flavours[i].str;
 445 }
 446
 447 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 448                                     int showdefaults)
 449 {
 450         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 451
 452         switch (sap->sa_family) {
 453         case AF_INET: {
 454                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 455                 seq_printf(m, ",mountaddr=" NIPQUAD_FMT,
 456                                 NIPQUAD(sin->sin_addr.s_addr));
 457                 break;
 458         }
 459         case AF_INET6: {
 460                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 461                 seq_printf(m, ",mountaddr=" NIP6_FMT,
 462                                 NIP6(sin6->sin6_addr));
 463                 break;
 464         }
 465         default:
 466                 if (showdefaults)
 467                         seq_printf(m, ",mountaddr=unspecified");
 468         }
 469
 470         if (nfss->mountd_version || showdefaults)
 471                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 472         if (nfss->mountd_port || showdefaults)
 473                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 474
 475         switch (nfss->mountd_protocol) {
 476         case IPPROTO_UDP:
 477                 seq_printf(m, ",mountproto=udp");
 478                 break;
 479         case IPPROTO_TCP:
 480                 seq_printf(m, ",mountproto=tcp");
 481                 break;
 482         default:
 483                 if (showdefaults)
 484                         seq_printf(m, ",mountproto=auto");
 485         }
 486 }
 487
 488 /*
 489  * Describe the mount options in force on this server representation
 490  */
 491 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 492                                    int showdefaults)
 493 {
 494         static const struct proc_nfs_info {
 495                 int flag;
 496                 const char *str;
 497                 const char *nostr;
 498         } nfs_info[] = {
 499                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 500                 { NFS_MOUNT_INTR, ",intr", ",nointr" },
 501                 { NFS_MOUNT_POSIX, ",posix", "" },
 502                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 503                 { NFS_MOUNT_NOAC, ",noac", "" },
 504                 { NFS_MOUNT_NONLM, ",nolock", "" },
 505                 { NFS_MOUNT_NOACL, ",noacl", "" },
 506                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 507                 { NFS_MOUNT_UNSHARED, ",nosharecache", ""},
 508                 { 0, NULL, NULL }
 509         };
 510         const struct proc_nfs_info *nfs_infop;
 511         struct nfs_client *clp = nfss->nfs_client;
 512         u32 version = clp->rpc_ops->version;
 513
 514         seq_printf(m, ",vers=%u", version);
 515         seq_printf(m, ",rsize=%u", nfss->rsize);
 516         seq_printf(m, ",wsize=%u", nfss->wsize);
 517         if (nfss->bsize != 0)
 518                 seq_printf(m, ",bsize=%u", nfss->bsize);
 519         seq_printf(m, ",namlen=%u", nfss->namelen);
 520         if (nfss->acregmin != 3*HZ || showdefaults)
 521                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 522         if (nfss->acregmax != 60*HZ || showdefaults)
 523                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 524         if (nfss->acdirmin != 30*HZ || showdefaults)
 525                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 526         if (nfss->acdirmax != 60*HZ || showdefaults)
 527                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 528         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 529                 if (nfss->flags & nfs_infop->flag)
 530                         seq_puts(m, nfs_infop->str);
 531                 else
 532                         seq_puts(m, nfs_infop->nostr);
 533         }
 534         seq_printf(m, ",proto=%s",
 535                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 536         if (version == 4) {
 537                 if (nfss->port != NFS_PORT)
 538                         seq_printf(m, ",port=%u", nfss->port);
 539         } else
 540                 if (nfss->port)
 541                         seq_printf(m, ",port=%u", nfss->port);
 542
 543         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 544         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 545         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 546
 547         if (version != 4)
 548                 nfs_show_mountd_options(m, nfss, showdefaults);
 549
 550 #ifdef CONFIG_NFS_V4
 551         if (clp->rpc_ops->version == 4)
 552                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 553 #endif
 554 }
 555
 556 /*
 557  * Describe the mount options on this VFS mountpoint
 558  */
 559 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 560 {
 561         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 562
 563         nfs_show_mount_options(m, nfss, 0);
 564
 565         seq_printf(m, ",addr=%s",
 566                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 567                                                         RPC_DISPLAY_ADDR));
 568
 569         return 0;
 570 }
 571
 572 /*
 573  * Present statistical information for this VFS mountpoint
 574  */
 575 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 576 {
 577         int i, cpu;
 578         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 579         struct rpc_auth *auth = nfss->client->cl_auth;
 580         struct nfs_iostats totals = { };
 581
 582         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 583
 584         /*
 585          * Display all mount option settings
 586          */
 587         seq_printf(m, "\n\topts:\t");
 588         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 589         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 590         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 591         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 592         nfs_show_mount_options(m, nfss, 1);
 593
 594         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 595
 596         seq_printf(m, "\n\tcaps:\t");
 597         seq_printf(m, "caps=0x%x", nfss->caps);
 598         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 599         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 600         seq_printf(m, ",bsize=%u", nfss->bsize);
 601         seq_printf(m, ",namlen=%u", nfss->namelen);
 602
 603 #ifdef CONFIG_NFS_V4
 604         if (nfss->nfs_client->rpc_ops->version == 4) {
 605                 seq_printf(m, "\n\tnfsv4:\t");
 606                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 607                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 608                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 609         }
 610 #endif
 611
 612         /*
 613          * Display security flavor in effect for this mount
 614          */
 615         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 616         if (auth->au_flavor)
 617                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 618
 619         /*
 620          * Display superblock I/O counters
 621          */
 622         for_each_possible_cpu(cpu) {
 623                 struct nfs_iostats *stats;
 624
 625                 preempt_disable();
 626                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 627
 628                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 629                         totals.events[i] += stats->events[i];
 630                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 631                         totals.bytes[i] += stats->bytes[i];
 632
 633                 preempt_enable();
 634         }
 635
 636         seq_printf(m, "\n\tevents:\t");
 637         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 638                 seq_printf(m, "%lu ", totals.events[i]);
 639         seq_printf(m, "\n\tbytes:\t");
 640         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 641                 seq_printf(m, "%Lu ", totals.bytes[i]);
 642         seq_printf(m, "\n");
 643
 644         rpc_print_iostats(m, nfss->client);
 645
 646         return 0;
 647 }
 648
 649 /*
 650  * Begin unmount by attempting to remove all automounted mountpoints we added
 651  * in response to xdev traversals and referrals
 652  */
 653 static void nfs_umount_begin(struct super_block *sb)
 654 {
 655         struct nfs_server *server = NFS_SB(sb);
 656         struct rpc_clnt *rpc;
 657
 658         /* -EIO all pending I/O */
 659         rpc = server->client_acl;
 660         if (!IS_ERR(rpc))
 661                 rpc_killall_tasks(rpc);
 662         rpc = server->client;
 663         if (!IS_ERR(rpc))
 664                 rpc_killall_tasks(rpc);
 665 }
 666
 667 /*
 668  * Set the port number in an address.  Be agnostic about the address family.
 669  */
 670 static void nfs_set_port(struct sockaddr *sap, unsigned short port)
 671 {
 672         switch (sap->sa_family) {
 673         case AF_INET: {
 674                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 675                 ap->sin_port = htons(port);
 676                 break;
 677         }
 678         case AF_INET6: {
 679                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 680                 ap->sin6_port = htons(port);
 681                 break;
 682         }
 683         }
 684 }
 685
 686 /*
 687  * Sanity-check a server address provided by the mount command.
 688  *
 689  * Address family must be initialized, and address must not be
 690  * the ANY address for that family.
 691  */
 692 static int nfs_verify_server_address(struct sockaddr *addr)
 693 {
 694         switch (addr->sa_family) {
 695         case AF_INET: {
 696                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 697                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 698         }
 699         case AF_INET6: {
 700                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 701                 return !ipv6_addr_any(sa);
 702         }
 703         }
 704
 705         return 0;
 706 }
 707
 708 static void nfs_parse_ipv4_address(char *string, size_t str_len,
 709                                    struct sockaddr *sap, size_t *addr_len)
 710 {
 711         struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 712         u8 *addr = (u8 *)&sin->sin_addr.s_addr;
 713
 714         if (str_len <= INET_ADDRSTRLEN) {
 715                 dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
 716                                 (int)str_len, string);
 717
 718                 sin->sin_family = AF_INET;
 719                 *addr_len = sizeof(*sin);
 720                 if (in4_pton(string, str_len, addr, '\0', NULL))
 721                         return;
 722         }
 723
 724         sap->sa_family = AF_UNSPEC;
 725         *addr_len = 0;
 726 }
 727
 728 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 729 static void nfs_parse_ipv6_address(char *string, size_t str_len,
 730                                    struct sockaddr *sap, size_t *addr_len)
 731 {
 732         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 733         u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
 734
 735         if (str_len <= INET6_ADDRSTRLEN) {
 736                 dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
 737                                 (int)str_len, string);
 738
 739                 sin6->sin6_family = AF_INET6;
 740                 *addr_len = sizeof(*sin6);
 741                 if (in6_pton(string, str_len, addr, '\0', NULL))
 742                         return;
 743         }
 744
 745         sap->sa_family = AF_UNSPEC;
 746         *addr_len = 0;
 747 }
 748 #else
 749 static void nfs_parse_ipv6_address(char *string, size_t str_len,
 750                                    struct sockaddr *sap, size_t *addr_len)
 751 {
 752         sap->sa_family = AF_UNSPEC;
 753         *addr_len = 0;
 754 }
 755 #endif
 756
 757 /*
 758  * Construct a sockaddr based on the contents of a string that contains
 759  * an IP address in presentation format.
 760  *
 761  * If there is a problem constructing the new sockaddr, set the address
 762  * family to AF_UNSPEC.
 763  */
 764 static void nfs_parse_ip_address(char *string, size_t str_len,
 765                                  struct sockaddr *sap, size_t *addr_len)
 766 {
 767         unsigned int i, colons;
 768
 769         colons = 0;
 770         for (i = 0; i < str_len; i++)
 771                 if (string[i] == ':')
 772                         colons++;
 773
 774         if (colons >= 2)
 775                 nfs_parse_ipv6_address(string, str_len, sap, addr_len);
 776         else
 777                 nfs_parse_ipv4_address(string, str_len, sap, addr_len);
 778 }
 779
 780 /*
 781  * Error-check and convert a string of mount options from user space into
 782  * a data structure
 783  */
 784 static int nfs_parse_mount_options(char *raw,
 785                                    struct nfs_parsed_mount_data *mnt)
 786 {
 787         char *p, *string, *secdata;
 788         int rc;
 789
 790         if (!raw) {
 791                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 792                 return 1;
 793         }
 794         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 795
 796         secdata = alloc_secdata();
 797         if (!secdata)
 798                 goto out_nomem;
 799
 800         rc = security_sb_copy_data(raw, secdata);
 801         if (rc)
 802                 goto out_security_failure;
 803
 804         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 805         if (rc)
 806                 goto out_security_failure;
 807
 808         free_secdata(secdata);
 809
 810         while ((p = strsep(&raw, ",")) != NULL) {
 811                 substring_t args[MAX_OPT_ARGS];
 812                 int option, token;
 813
 814                 if (!*p)
 815                         continue;
 816
 817                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 818
 819                 token = match_token(p, nfs_mount_option_tokens, args);
 820                 switch (token) {
 821                 case Opt_soft:
 822                         mnt->flags |= NFS_MOUNT_SOFT;
 823                         break;
 824                 case Opt_hard:
 825                         mnt->flags &= ~NFS_MOUNT_SOFT;
 826                         break;
 827                 case Opt_posix:
 828                         mnt->flags |= NFS_MOUNT_POSIX;
 829                         break;
 830                 case Opt_noposix:
 831                         mnt->flags &= ~NFS_MOUNT_POSIX;
 832                         break;
 833                 case Opt_cto:
 834                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 835                         break;
 836                 case Opt_nocto:
 837                         mnt->flags |= NFS_MOUNT_NOCTO;
 838                         break;
 839                 case Opt_ac:
 840                         mnt->flags &= ~NFS_MOUNT_NOAC;
 841                         break;
 842                 case Opt_noac:
 843                         mnt->flags |= NFS_MOUNT_NOAC;
 844                         break;
 845                 case Opt_lock:
 846                         mnt->flags &= ~NFS_MOUNT_NONLM;
 847                         break;
 848                 case Opt_nolock:
 849                         mnt->flags |= NFS_MOUNT_NONLM;
 850                         break;
 851                 case Opt_v2:
 852                         mnt->flags &= ~NFS_MOUNT_VER3;
 853                         break;
 854                 case Opt_v3:
 855                         mnt->flags |= NFS_MOUNT_VER3;
 856                         break;
 857                 case Opt_udp:
 858                         mnt->flags &= ~NFS_MOUNT_TCP;
 859                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 860                         mnt->timeo = 7;
 861                         mnt->retrans = 5;
 862                         break;
 863                 case Opt_tcp:
 864                         mnt->flags |= NFS_MOUNT_TCP;
 865                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 866                         mnt->timeo = 600;
 867                         mnt->retrans = 2;
 868                         break;
 869                 case Opt_rdma:
 870                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 871                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 872                         mnt->timeo = 600;
 873                         mnt->retrans = 2;
 874                         break;
 875                 case Opt_acl:
 876                         mnt->flags &= ~NFS_MOUNT_NOACL;
 877                         break;
 878                 case Opt_noacl:
 879                         mnt->flags |= NFS_MOUNT_NOACL;
 880                         break;
 881                 case Opt_rdirplus:
 882                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 883                         break;
 884                 case Opt_nordirplus:
 885                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 886                         break;
 887                 case Opt_sharecache:
 888                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 889                         break;
 890                 case Opt_nosharecache:
 891                         mnt->flags |= NFS_MOUNT_UNSHARED;
 892                         break;
 893
 894                 case Opt_port:
 895                         if (match_int(args, &option))
 896                                 return 0;
 897                         if (option < 0 || option > 65535)
 898                                 return 0;
 899                         mnt->nfs_server.port = option;
 900                         break;
 901                 case Opt_rsize:
 902                         if (match_int(args, &mnt->rsize))
 903                                 return 0;
 904                         break;
 905                 case Opt_wsize:
 906                         if (match_int(args, &mnt->wsize))
 907                                 return 0;
 908                         break;
 909                 case Opt_bsize:
 910                         if (match_int(args, &option))
 911                                 return 0;
 912                         if (option < 0)
 913                                 return 0;
 914                         mnt->bsize = option;
 915                         break;
 916                 case Opt_timeo:
 917                         if (match_int(args, &mnt->timeo))
 918                                 return 0;
 919                         break;
 920                 case Opt_retrans:
 921                         if (match_int(args, &mnt->retrans))
 922                                 return 0;
 923                         break;
 924                 case Opt_acregmin:
 925                         if (match_int(args, &mnt->acregmin))
 926                                 return 0;
 927                         break;
 928                 case Opt_acregmax:
 929                         if (match_int(args, &mnt->acregmax))
 930                                 return 0;
 931                         break;
 932                 case Opt_acdirmin:
 933                         if (match_int(args, &mnt->acdirmin))
 934                                 return 0;
 935                         break;
 936                 case Opt_acdirmax:
 937                         if (match_int(args, &mnt->acdirmax))
 938                                 return 0;
 939                         break;
 940                 case Opt_actimeo:
 941                         if (match_int(args, &option))
 942                                 return 0;
 943                         if (option < 0)
 944                                 return 0;
 945                         mnt->acregmin =
 946                         mnt->acregmax =
 947                         mnt->acdirmin =
 948                         mnt->acdirmax = option;
 949                         break;
 950                 case Opt_namelen:
 951                         if (match_int(args, &mnt->namlen))
 952                                 return 0;
 953                         break;
 954                 case Opt_mountport:
 955                         if (match_int(args, &option))
 956                                 return 0;
 957                         if (option < 0 || option > 65535)
 958                                 return 0;
 959                         mnt->mount_server.port = option;
 960                         break;
 961                 case Opt_mountvers:
 962                         if (match_int(args, &option))
 963                                 return 0;
 964                         if (option < 0)
 965                                 return 0;
 966                         mnt->mount_server.version = option;
 967                         break;
 968                 case Opt_nfsvers:
 969                         if (match_int(args, &option))
 970                                 return 0;
 971                         switch (option) {
 972                         case 2:
 973                                 mnt->flags &= ~NFS_MOUNT_VER3;
 974                                 break;
 975                         case 3:
 976                                 mnt->flags |= NFS_MOUNT_VER3;
 977                                 break;
 978                         default:
 979                                 goto out_unrec_vers;
 980                         }
 981                         break;
 982
 983                 case Opt_sec:
 984                         string = match_strdup(args);
 985                         if (string == NULL)
 986                                 goto out_nomem;
 987                         token = match_token(string, nfs_secflavor_tokens, args);
 988                         kfree(string);
 989
 990                         /*
 991                          * The flags setting is for v2/v3.  The flavor_len
 992                          * setting is for v4.  v2/v3 also need to know the
 993                          * difference between NULL and UNIX.
 994                          */
 995                         switch (token) {
 996                         case Opt_sec_none:
 997                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 998                                 mnt->auth_flavor_len = 0;
 999                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1000                                 break;
1001                         case Opt_sec_sys:
1002                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
1003                                 mnt->auth_flavor_len = 0;
1004                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1005                                 break;
1006                         case Opt_sec_krb5:
1007                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1008                                 mnt->auth_flavor_len = 1;
1009                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1010                                 break;
1011                         case Opt_sec_krb5i:
1012                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1013                                 mnt->auth_flavor_len = 1;
1014                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1015                                 break;
1016                         case Opt_sec_krb5p:
1017                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1018                                 mnt->auth_flavor_len = 1;
1019                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1020                                 break;
1021                         case Opt_sec_lkey:
1022                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1023                                 mnt->auth_flavor_len = 1;
1024                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1025                                 break;
1026                         case Opt_sec_lkeyi:
1027                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1028                                 mnt->auth_flavor_len = 1;
1029                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1030                                 break;
1031                         case Opt_sec_lkeyp:
1032                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1033                                 mnt->auth_flavor_len = 1;
1034                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1035                                 break;
1036                         case Opt_sec_spkm:
1037                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1038                                 mnt->auth_flavor_len = 1;
1039                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1040                                 break;
1041                         case Opt_sec_spkmi:
1042                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1043                                 mnt->auth_flavor_len = 1;
1044                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1045                                 break;
1046                         case Opt_sec_spkmp:
1047                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1048                                 mnt->auth_flavor_len = 1;
1049                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1050                                 break;
1051                         default:
1052                                 goto out_unrec_sec;
1053                         }
1054                         break;
1055                 case Opt_proto:
1056                         string = match_strdup(args);
1057                         if (string == NULL)
1058                                 goto out_nomem;
1059                         token = match_token(string,
1060                                             nfs_xprt_protocol_tokens, args);
1061                         kfree(string);
1062
1063                         switch (token) {
1064                         case Opt_xprt_udp:
1065                                 mnt->flags &= ~NFS_MOUNT_TCP;
1066                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1067                                 mnt->timeo = 7;
1068                                 mnt->retrans = 5;
1069                                 break;
1070                         case Opt_xprt_tcp:
1071                                 mnt->flags |= NFS_MOUNT_TCP;
1072                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1073                                 mnt->timeo = 600;
1074                                 mnt->retrans = 2;
1075                                 break;
1076                         case Opt_xprt_rdma:
1077                                 /* vector side protocols to TCP */
1078                                 mnt->flags |= NFS_MOUNT_TCP;
1079                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1080                                 mnt->timeo = 600;
1081                                 mnt->retrans = 2;
1082                                 break;
1083                         default:
1084                                 goto out_unrec_xprt;
1085                         }
1086                         break;
1087                 case Opt_mountproto:
1088                         string = match_strdup(args);
1089                         if (string == NULL)
1090                                 goto out_nomem;
1091                         token = match_token(string,
1092                                             nfs_xprt_protocol_tokens, args);
1093                         kfree(string);
1094
1095                         switch (token) {
1096                         case Opt_xprt_udp:
1097                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1098                                 break;
1099                         case Opt_xprt_tcp:
1100                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1101                                 break;
1102                         case Opt_xprt_rdma: /* not used for side protocols */
1103                         default:
1104                                 goto out_unrec_xprt;
1105                         }
1106                         break;
1107                 case Opt_addr:
1108                         string = match_strdup(args);
1109                         if (string == NULL)
1110                                 goto out_nomem;
1111                         nfs_parse_ip_address(string, strlen(string),
1112                                              (struct sockaddr *)
1113                                                 &mnt->nfs_server.address,
1114                                              &mnt->nfs_server.addrlen);
1115                         kfree(string);
1116                         break;
1117                 case Opt_clientaddr:
1118                         string = match_strdup(args);
1119                         if (string == NULL)
1120                                 goto out_nomem;
1121                         kfree(mnt->client_address);
1122                         mnt->client_address = string;
1123                         break;
1124                 case Opt_mounthost:
1125                         string = match_strdup(args);
1126                         if (string == NULL)
1127                                 goto out_nomem;
1128                         kfree(mnt->mount_server.hostname);
1129                         mnt->mount_server.hostname = string;
1130                         break;
1131                 case Opt_mountaddr:
1132                         string = match_strdup(args);
1133                         if (string == NULL)
1134                                 goto out_nomem;
1135                         nfs_parse_ip_address(string, strlen(string),
1136                                              (struct sockaddr *)
1137                                                 &mnt->mount_server.address,
1138                                              &mnt->mount_server.addrlen);
1139                         kfree(string);
1140                         break;
1141
1142                 case Opt_userspace:
1143                 case Opt_deprecated:
1144                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1145                                         "'%s'\n", p);
1146                         break;
1147
1148                 default:
1149                         goto out_unknown;
1150                 }
1151         }
1152
1153         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
1154                                 mnt->nfs_server.port);
1155
1156         return 1;
1157
1158 out_nomem:
1159         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1160         return 0;
1161 out_security_failure:
1162         free_secdata(secdata);
1163         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1164         return 0;
1165 out_unrec_vers:
1166         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1167         return 0;
1168
1169 out_unrec_xprt:
1170         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1171         return 0;
1172
1173 out_unrec_sec:
1174         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1175         return 0;
1176
1177 out_unknown:
1178         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1179         return 0;
1180 }
1181
1182 /*
1183  * Use the remote server's MOUNT service to request the NFS file handle
1184  * corresponding to the provided path.
1185  */
1186 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1187                          struct nfs_fh *root_fh)
1188 {
1189         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1190         char *hostname;
1191         int status;
1192
1193         if (args->mount_server.version == 0) {
1194                 if (args->flags & NFS_MOUNT_VER3)
1195                         args->mount_server.version = NFS_MNT3_VERSION;
1196                 else
1197                         args->mount_server.version = NFS_MNT_VERSION;
1198         }
1199
1200         if (args->mount_server.hostname)
1201                 hostname = args->mount_server.hostname;
1202         else
1203                 hostname = args->nfs_server.hostname;
1204
1205         /*
1206          * Construct the mount server's address.
1207          */
1208         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1209                 memcpy(sap, &args->nfs_server.address,
1210                        args->nfs_server.addrlen);
1211                 args->mount_server.addrlen = args->nfs_server.addrlen;
1212         }
1213
1214         /*
1215          * autobind will be used if mount_server.port == 0
1216          */
1217         nfs_set_port(sap, args->mount_server.port);
1218
1219         /*
1220          * Now ask the mount server to map our export path
1221          * to a file handle.
1222          */
1223         status = nfs_mount(sap,
1224                            args->mount_server.addrlen,
1225                            hostname,
1226                            args->nfs_server.export_path,
1227                            args->mount_server.version,
1228                            args->mount_server.protocol,
1229                            root_fh);
1230         if (status == 0)
1231                 return 0;
1232
1233         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1234                         hostname, status);
1235         return status;
1236 }
1237
1238 static int nfs_parse_simple_hostname(const char *dev_name,
1239                                      char **hostname, size_t maxnamlen,
1240                                      char **export_path, size_t maxpathlen)
1241 {
1242         size_t len;
1243         char *colon, *comma;
1244
1245         colon = strchr(dev_name, ':');
1246         if (colon == NULL)
1247                 goto out_bad_devname;
1248
1249         len = colon - dev_name;
1250         if (len > maxnamlen)
1251                 goto out_hostname;
1252
1253         /* N.B. caller will free nfs_server.hostname in all cases */
1254         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1255         if (!*hostname)
1256                 goto out_nomem;
1257
1258         /* kill possible hostname list: not supported */
1259         comma = strchr(*hostname, ',');
1260         if (comma != NULL) {
1261                 if (comma == *hostname)
1262                         goto out_bad_devname;
1263                 *comma = '\0';
1264         }
1265
1266         colon++;
1267         len = strlen(colon);
1268         if (len > maxpathlen)
1269                 goto out_path;
1270         *export_path = kstrndup(colon, len, GFP_KERNEL);
1271         if (!*export_path)
1272                 goto out_nomem;
1273
1274         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1275         return 0;
1276
1277 out_bad_devname:
1278         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1279         return -EINVAL;
1280
1281 out_nomem:
1282         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1283         return -ENOMEM;
1284
1285 out_hostname:
1286         dfprintk(MOUNT, "NFS: server hostname too long\n");
1287         return -ENAMETOOLONG;
1288
1289 out_path:
1290         dfprintk(MOUNT, "NFS: export pathname too long\n");
1291         return -ENAMETOOLONG;
1292 }
1293
1294 /*
1295  * Hostname has square brackets around it because it contains one or
1296  * more colons.  We look for the first closing square bracket, and a
1297  * colon must follow it.
1298  */
1299 static int nfs_parse_protected_hostname(const char *dev_name,
1300                                         char **hostname, size_t maxnamlen,
1301                                         char **export_path, size_t maxpathlen)
1302 {
1303         size_t len;
1304         char *start, *end;
1305
1306         start = (char *)(dev_name + 1);
1307
1308         end = strchr(start, ']');
1309         if (end == NULL)
1310                 goto out_bad_devname;
1311         if (*(end + 1) != ':')
1312                 goto out_bad_devname;
1313
1314         len = end - start;
1315         if (len > maxnamlen)
1316                 goto out_hostname;
1317
1318         /* N.B. caller will free nfs_server.hostname in all cases */
1319         *hostname = kstrndup(start, len, GFP_KERNEL);
1320         if (*hostname == NULL)
1321                 goto out_nomem;
1322
1323         end += 2;
1324         len = strlen(end);
1325         if (len > maxpathlen)
1326                 goto out_path;
1327         *export_path = kstrndup(end, len, GFP_KERNEL);
1328         if (!*export_path)
1329                 goto out_nomem;
1330
1331         return 0;
1332
1333 out_bad_devname:
1334         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1335         return -EINVAL;
1336
1337 out_nomem:
1338         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1339         return -ENOMEM;
1340
1341 out_hostname:
1342         dfprintk(MOUNT, "NFS: server hostname too long\n");
1343         return -ENAMETOOLONG;
1344
1345 out_path:
1346         dfprintk(MOUNT, "NFS: export pathname too long\n");
1347         return -ENAMETOOLONG;
1348 }
1349
1350 /*
1351  * Split "dev_name" into "hostname:export_path".
1352  *
1353  * The leftmost colon demarks the split between the server's hostname
1354  * and the export path.  If the hostname starts with a left square
1355  * bracket, then it may contain colons.
1356  *
1357  * Note: caller frees hostname and export path, even on error.
1358  */
1359 static int nfs_parse_devname(const char *dev_name,
1360                              char **hostname, size_t maxnamlen,
1361                              char **export_path, size_t maxpathlen)
1362 {
1363         if (*dev_name == '[')
1364                 return nfs_parse_protected_hostname(dev_name,
1365                                                     hostname, maxnamlen,
1366                                                     export_path, maxpathlen);
1367
1368         return nfs_parse_simple_hostname(dev_name,
1369                                          hostname, maxnamlen,
1370                                          export_path, maxpathlen);
1371 }
1372
1373 /*
1374  * Validate the NFS2/NFS3 mount data
1375  * - fills in the mount root filehandle
1376  *
1377  * For option strings, user space handles the following behaviors:
1378  *
1379  * + DNS: mapping server host name to IP address ("addr=" option)
1380  *
1381  * + failure mode: how to behave if a mount request can't be handled
1382  *   immediately ("fg/bg" option)
1383  *
1384  * + retry: how often to retry a mount request ("retry=" option)
1385  *
1386  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1387  *   mountproto=tcp after mountproto=udp, and so on
1388  */
1389 static int nfs_validate_mount_data(void *options,
1390                                    struct nfs_parsed_mount_data *args,
1391                                    struct nfs_fh *mntfh,
1392                                    const char *dev_name)
1393 {
1394         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1395
1396         if (data == NULL)
1397                 goto out_no_data;
1398
1399         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1400         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1401         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1402         args->timeo             = 600;
1403         args->retrans           = 2;
1404         args->acregmin          = 3;
1405         args->acregmax          = 60;
1406         args->acdirmin          = 30;
1407         args->acdirmax          = 60;
1408         args->mount_server.port = 0;    /* autobind unless user sets port */
1409         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1410         args->nfs_server.port   = 0;    /* autobind unless user sets port */
1411         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1412
1413         switch (data->version) {
1414         case 1:
1415                 data->namlen = 0;
1416         case 2:
1417                 data->bsize = 0;
1418         case 3:
1419                 if (data->flags & NFS_MOUNT_VER3)
1420                         goto out_no_v3;
1421                 data->root.size = NFS2_FHSIZE;
1422                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1423         case 4:
1424                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1425                         goto out_no_sec;
1426         case 5:
1427                 memset(data->context, 0, sizeof(data->context));
1428         case 6:
1429                 if (data->flags & NFS_MOUNT_VER3) {
1430                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1431                                 goto out_invalid_fh;
1432                         mntfh->size = data->root.size;
1433                 } else
1434                         mntfh->size = NFS2_FHSIZE;
1435
1436
1437                 memcpy(mntfh->data, data->root.data, mntfh->size);
1438                 if (mntfh->size < sizeof(mntfh->data))
1439                         memset(mntfh->data + mntfh->size, 0,
1440                                sizeof(mntfh->data) - mntfh->size);
1441
1442                 /*
1443                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1444                  * can deal with.
1445                  */
1446                 args->flags             = data->flags;
1447                 args->rsize             = data->rsize;
1448                 args->wsize             = data->wsize;
1449                 args->timeo             = data->timeo;
1450                 args->retrans           = data->retrans;
1451                 args->acregmin          = data->acregmin;
1452                 args->acregmax          = data->acregmax;
1453                 args->acdirmin          = data->acdirmin;
1454                 args->acdirmax          = data->acdirmax;
1455
1456                 memcpy(&args->nfs_server.address, &data->addr,
1457                        sizeof(data->addr));
1458                 args->nfs_server.addrlen = sizeof(data->addr);
1459                 if (!nfs_verify_server_address((struct sockaddr *)
1460                                                 &args->nfs_server.address))
1461                         goto out_no_address;
1462
1463                 if (!(data->flags & NFS_MOUNT_TCP))
1464                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1465                 /* N.B. caller will free nfs_server.hostname in all cases */
1466                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1467                 args->namlen            = data->namlen;
1468                 args->bsize             = data->bsize;
1469                 args->auth_flavors[0]   = data->pseudoflavor;
1470                 if (!args->nfs_server.hostname)
1471                         goto out_nomem;
1472
1473                 /*
1474                  * The legacy version 6 binary mount data from userspace has a
1475                  * field used only to transport selinux information into the
1476                  * the kernel.  To continue to support that functionality we
1477                  * have a touch of selinux knowledge here in the NFS code. The
1478                  * userspace code converted context=blah to just blah so we are
1479                  * converting back to the full string selinux understands.
1480                  */
1481                 if (data->context[0]){
1482 #ifdef CONFIG_SECURITY_SELINUX
1483                         int rc;
1484                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1485                         if (!opts_str)
1486                                 return -ENOMEM;
1487                         strcpy(opts_str, "context=");
1488                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1489                         strcat(opts_str, &data->context[0]);
1490                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1491                         kfree(opts_str);
1492                         if (rc)
1493                                 return rc;
1494 #else
1495                         return -EINVAL;
1496 #endif
1497                 }
1498
1499                 break;
1500         default: {
1501                 int status;
1502
1503                 if (nfs_parse_mount_options((char *)options, args) == 0)
1504                         return -EINVAL;
1505
1506                 if (!nfs_verify_server_address((struct sockaddr *)
1507                                                 &args->nfs_server.address))
1508                         goto out_no_address;
1509
1510                 status = nfs_parse_devname(dev_name,
1511                                            &args->nfs_server.hostname,
1512                                            PAGE_SIZE,
1513                                            &args->nfs_server.export_path,
1514                                            NFS_MAXPATHLEN);
1515                 if (!status)
1516                         status = nfs_try_mount(args, mntfh);
1517
1518                 kfree(args->nfs_server.export_path);
1519                 args->nfs_server.export_path = NULL;
1520
1521                 if (status)
1522                         return status;
1523
1524                 break;
1525                 }
1526         }
1527
1528         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1529                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1530
1531 #ifndef CONFIG_NFS_V3
1532         if (args->flags & NFS_MOUNT_VER3)
1533                 goto out_v3_not_compiled;
1534 #endif /* !CONFIG_NFS_V3 */
1535
1536         return 0;
1537
1538 out_no_data:
1539         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1540         return -EINVAL;
1541
1542 out_no_v3:
1543         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1544                  data->version);
1545         return -EINVAL;
1546
1547 out_no_sec:
1548         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1549         return -EINVAL;
1550
1551 #ifndef CONFIG_NFS_V3
1552 out_v3_not_compiled:
1553         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1554         return -EPROTONOSUPPORT;
1555 #endif /* !CONFIG_NFS_V3 */
1556
1557 out_nomem:
1558         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1559         return -ENOMEM;
1560
1561 out_no_address:
1562         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1563         return -EINVAL;
1564
1565 out_invalid_fh:
1566         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1567         return -EINVAL;
1568 }
1569
1570 static int
1571 nfs_compare_remount_data(struct nfs_server *nfss,
1572                          struct nfs_parsed_mount_data *data)
1573 {
1574         if (data->flags != nfss->flags ||
1575             data->rsize != nfss->rsize ||
1576             data->wsize != nfss->wsize ||
1577             data->retrans != nfss->client->cl_timeout->to_retries ||
1578             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1579             data->acregmin != nfss->acregmin / HZ ||
1580             data->acregmax != nfss->acregmax / HZ ||
1581             data->acdirmin != nfss->acdirmin / HZ ||
1582             data->acdirmax != nfss->acdirmax / HZ ||
1583             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1584             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1585             memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1586                    data->nfs_server.addrlen) != 0)
1587                 return -EINVAL;
1588
1589         return 0;
1590 }
1591
1592 static int
1593 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1594 {
1595         int error;
1596         struct nfs_server *nfss = sb->s_fs_info;
1597         struct nfs_parsed_mount_data *data;
1598         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1599         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1600         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1601
1602         /*
1603          * Userspace mount programs that send binary options generally send
1604          * them populated with default values. We have no way to know which
1605          * ones were explicitly specified. Fall back to legacy behavior and
1606          * just return success.
1607          */
1608         if ((nfsvers == 4 && options4->version == 1) ||
1609             (nfsvers <= 3 && options->version >= 1 &&
1610              options->version <= 6))
1611                 return 0;
1612
1613         data = kzalloc(sizeof(*data), GFP_KERNEL);
1614         if (data == NULL)
1615                 return -ENOMEM;
1616
1617         /* fill out struct with values from existing mount */
1618         data->flags = nfss->flags;
1619         data->rsize = nfss->rsize;
1620         data->wsize = nfss->wsize;
1621         data->retrans = nfss->client->cl_timeout->to_retries;
1622         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1623         data->acregmin = nfss->acregmin / HZ;
1624         data->acregmax = nfss->acregmax / HZ;
1625         data->acdirmin = nfss->acdirmin / HZ;
1626         data->acdirmax = nfss->acdirmax / HZ;
1627         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1628         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1629         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1630                 data->nfs_server.addrlen);
1631
1632         /* overwrite those values with any that were specified */
1633         error = nfs_parse_mount_options((char *)options, data);
1634         if (error < 0)
1635                 goto out;
1636
1637         /* compare new mount options with old ones */
1638         error = nfs_compare_remount_data(nfss, data);
1639 out:
1640         kfree(data);
1641         return error;
1642 }
1643
1644 /*
1645  * Initialise the common bits of the superblock
1646  */
1647 static inline void nfs_initialise_sb(struct super_block *sb)
1648 {
1649         struct nfs_server *server = NFS_SB(sb);
1650
1651         sb->s_magic = NFS_SUPER_MAGIC;
1652
1653         /* We probably want something more informative here */
1654         snprintf(sb->s_id, sizeof(sb->s_id),
1655                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1656
1657         if (sb->s_blocksize == 0)
1658                 sb->s_blocksize = nfs_block_bits(server->wsize,
1659                                                  &sb->s_blocksize_bits);
1660
1661         if (server->flags & NFS_MOUNT_NOAC)
1662                 sb->s_flags |= MS_SYNCHRONOUS;
1663
1664         nfs_super_set_maxbytes(sb, server->maxfilesize);
1665 }
1666
1667 /*
1668  * Finish setting up an NFS2/3 superblock
1669  */
1670 static void nfs_fill_super(struct super_block *sb,
1671                            struct nfs_parsed_mount_data *data)
1672 {
1673         struct nfs_server *server = NFS_SB(sb);
1674
1675         sb->s_blocksize_bits = 0;
1676         sb->s_blocksize = 0;
1677         if (data->bsize)
1678                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1679
1680         if (server->flags & NFS_MOUNT_VER3) {
1681                 /* The VFS shouldn't apply the umask to mode bits. We will do
1682                  * so ourselves when necessary.
1683                  */
1684                 sb->s_flags |= MS_POSIXACL;
1685                 sb->s_time_gran = 1;
1686         }
1687
1688         sb->s_op = &nfs_sops;
1689         nfs_initialise_sb(sb);
1690 }
1691
1692 /*
1693  * Finish setting up a cloned NFS2/3 superblock
1694  */
1695 static void nfs_clone_super(struct super_block *sb,
1696                             const struct super_block *old_sb)
1697 {
1698         struct nfs_server *server = NFS_SB(sb);
1699
1700         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1701         sb->s_blocksize = old_sb->s_blocksize;
1702         sb->s_maxbytes = old_sb->s_maxbytes;
1703
1704         if (server->flags & NFS_MOUNT_VER3) {
1705                 /* The VFS shouldn't apply the umask to mode bits. We will do
1706                  * so ourselves when necessary.
1707                  */
1708                 sb->s_flags |= MS_POSIXACL;
1709                 sb->s_time_gran = 1;
1710         }
1711
1712         sb->s_op = old_sb->s_op;
1713         nfs_initialise_sb(sb);
1714 }
1715
1716 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1717
1718 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1719 {
1720         const struct nfs_server *a = s->s_fs_info;
1721         const struct rpc_clnt *clnt_a = a->client;
1722         const struct rpc_clnt *clnt_b = b->client;
1723
1724         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1725                 goto Ebusy;
1726         if (a->nfs_client != b->nfs_client)
1727                 goto Ebusy;
1728         if (a->flags != b->flags)
1729                 goto Ebusy;
1730         if (a->wsize != b->wsize)
1731                 goto Ebusy;
1732         if (a->rsize != b->rsize)
1733                 goto Ebusy;
1734         if (a->acregmin != b->acregmin)
1735                 goto Ebusy;
1736         if (a->acregmax != b->acregmax)
1737                 goto Ebusy;
1738         if (a->acdirmin != b->acdirmin)
1739                 goto Ebusy;
1740         if (a->acdirmax != b->acdirmax)
1741                 goto Ebusy;
1742         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1743                 goto Ebusy;
1744         return 1;
1745 Ebusy:
1746         return 0;
1747 }
1748
1749 struct nfs_sb_mountdata {
1750         struct nfs_server *server;
1751         int mntflags;
1752 };
1753
1754 static int nfs_set_super(struct super_block *s, void *data)
1755 {
1756         struct nfs_sb_mountdata *sb_mntdata = data;
1757         struct nfs_server *server = sb_mntdata->server;
1758         int ret;
1759
1760         s->s_flags = sb_mntdata->mntflags;
1761         s->s_fs_info = server;
1762         ret = set_anon_super(s, server);
1763         if (ret == 0)
1764                 server->s_dev = s->s_dev;
1765         return ret;
1766 }
1767
1768 static int nfs_compare_super_address(struct nfs_server *server1,
1769                                      struct nfs_server *server2)
1770 {
1771         struct sockaddr *sap1, *sap2;
1772
1773         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1774         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1775
1776         if (sap1->sa_family != sap2->sa_family)
1777                 return 0;
1778
1779         switch (sap1->sa_family) {
1780         case AF_INET: {
1781                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1782                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1783                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1784                         return 0;
1785                 if (sin1->sin_port != sin2->sin_port)
1786                         return 0;
1787                 break;
1788         }
1789         case AF_INET6: {
1790                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1791                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1792                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1793                         return 0;
1794                 if (sin1->sin6_port != sin2->sin6_port)
1795                         return 0;
1796                 break;
1797         }
1798         default:
1799                 return 0;
1800         }
1801
1802         return 1;
1803 }
1804
1805 static int nfs_compare_super(struct super_block *sb, void *data)
1806 {
1807         struct nfs_sb_mountdata *sb_mntdata = data;
1808         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1809         int mntflags = sb_mntdata->mntflags;
1810
1811         if (!nfs_compare_super_address(old, server))
1812                 return 0;
1813         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1814         if (old->flags & NFS_MOUNT_UNSHARED)
1815                 return 0;
1816         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1817                 return 0;
1818         return nfs_compare_mount_options(sb, server, mntflags);
1819 }
1820
1821 static int nfs_bdi_register(struct nfs_server *server)
1822 {
1823         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
1824 }
1825
1826 static int nfs_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_server *server = NULL;
1830         struct super_block *s;
1831         struct nfs_parsed_mount_data *data;
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 = -ENOMEM;
1839
1840         data = kzalloc(sizeof(*data), GFP_KERNEL);
1841         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
1842         if (data == NULL || mntfh == NULL)
1843                 goto out_free_fh;
1844
1845         security_init_mnt_opts(&data->lsm_opts);
1846
1847         /* Validate the mount data */
1848         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
1849         if (error < 0)
1850                 goto out;
1851
1852         /* Get a volume representation */
1853         server = nfs_create_server(data, mntfh);
1854         if (IS_ERR(server)) {
1855                 error = PTR_ERR(server);
1856                 goto out;
1857         }
1858         sb_mntdata.server = server;
1859
1860         if (server->flags & NFS_MOUNT_UNSHARED)
1861                 compare_super = NULL;
1862
1863         /* Get a superblock - note that we may end up sharing one that already exists */
1864         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1865         if (IS_ERR(s)) {
1866                 error = PTR_ERR(s);
1867                 goto out_err_nosb;
1868         }
1869
1870         if (s->s_fs_info != server) {
1871                 nfs_free_server(server);
1872                 server = NULL;
1873         } else {
1874                 error = nfs_bdi_register(server);
1875                 if (error)
1876                         goto error_splat_super;
1877         }
1878
1879         if (!s->s_root) {
1880                 /* initial superblock/root creation */
1881                 nfs_fill_super(s, data);
1882         }
1883
1884         mntroot = nfs_get_root(s, mntfh);
1885         if (IS_ERR(mntroot)) {
1886                 error = PTR_ERR(mntroot);
1887                 goto error_splat_super;
1888         }
1889
1890         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
1891         if (error)
1892                 goto error_splat_root;
1893
1894         s->s_flags |= MS_ACTIVE;
1895         mnt->mnt_sb = s;
1896         mnt->mnt_root = mntroot;
1897         error = 0;
1898
1899 out:
1900         kfree(data->nfs_server.hostname);
1901         kfree(data->mount_server.hostname);
1902         security_free_mnt_opts(&data->lsm_opts);
1903 out_free_fh:
1904         kfree(mntfh);
1905         kfree(data);
1906         return error;
1907
1908 out_err_nosb:
1909         nfs_free_server(server);
1910         goto out;
1911
1912 error_splat_root:
1913         dput(mntroot);
1914 error_splat_super:
1915         up_write(&s->s_umount);
1916         deactivate_super(s);
1917         goto out;
1918 }
1919
1920 /*
1921  * Destroy an NFS2/3 superblock
1922  */
1923 static void nfs_kill_super(struct super_block *s)
1924 {
1925         struct nfs_server *server = NFS_SB(s);
1926
1927         bdi_unregister(&server->backing_dev_info);
1928         kill_anon_super(s);
1929         nfs_free_server(server);
1930 }
1931
1932 /*
1933  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1934  */
1935 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1936                            const char *dev_name, void *raw_data,
1937                            struct vfsmount *mnt)
1938 {
1939         struct nfs_clone_mount *data = raw_data;
1940         struct super_block *s;
1941         struct nfs_server *server;
1942         struct dentry *mntroot;
1943         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1944         struct nfs_sb_mountdata sb_mntdata = {
1945                 .mntflags = flags,
1946         };
1947         int error;
1948
1949         dprintk("--> nfs_xdev_get_sb()\n");
1950
1951         /* create a new volume representation */
1952         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1953         if (IS_ERR(server)) {
1954                 error = PTR_ERR(server);
1955                 goto out_err_noserver;
1956         }
1957         sb_mntdata.server = server;
1958
1959         if (server->flags & NFS_MOUNT_UNSHARED)
1960                 compare_super = NULL;
1961
1962         /* Get a superblock - note that we may end up sharing one that already exists */
1963         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1964         if (IS_ERR(s)) {
1965                 error = PTR_ERR(s);
1966                 goto out_err_nosb;
1967         }
1968
1969         if (s->s_fs_info != server) {
1970                 nfs_free_server(server);
1971                 server = NULL;
1972         } else {
1973                 error = nfs_bdi_register(server);
1974                 if (error)
1975                         goto error_splat_super;
1976         }
1977
1978         if (!s->s_root) {
1979                 /* initial superblock/root creation */
1980                 nfs_clone_super(s, data->sb);
1981         }
1982
1983         mntroot = nfs_get_root(s, data->fh);
1984         if (IS_ERR(mntroot)) {
1985                 error = PTR_ERR(mntroot);
1986                 goto error_splat_super;
1987         }
1988         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1989                 dput(mntroot);
1990                 error = -ESTALE;
1991                 goto error_splat_super;
1992         }
1993
1994         s->s_flags |= MS_ACTIVE;
1995         mnt->mnt_sb = s;
1996         mnt->mnt_root = mntroot;
1997
1998         /* clone any lsm security options from the parent to the new sb */
1999         security_sb_clone_mnt_opts(data->sb, s);
2000
2001         dprintk("<-- nfs_xdev_get_sb() = 0\n");
2002         return 0;
2003
2004 out_err_nosb:
2005         nfs_free_server(server);
2006 out_err_noserver:
2007         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
2008         return error;
2009
2010 error_splat_super:
2011         up_write(&s->s_umount);
2012         deactivate_super(s);
2013         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
2014         return error;
2015 }
2016
2017 #ifdef CONFIG_NFS_V4
2018
2019 /*
2020  * Finish setting up a cloned NFS4 superblock
2021  */
2022 static void nfs4_clone_super(struct super_block *sb,
2023                             const struct super_block *old_sb)
2024 {
2025         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2026         sb->s_blocksize = old_sb->s_blocksize;
2027         sb->s_maxbytes = old_sb->s_maxbytes;
2028         sb->s_time_gran = 1;
2029         sb->s_op = old_sb->s_op;
2030         nfs_initialise_sb(sb);
2031 }
2032
2033 /*
2034  * Set up an NFS4 superblock
2035  */
2036 static void nfs4_fill_super(struct super_block *sb)
2037 {
2038         sb->s_time_gran = 1;
2039         sb->s_op = &nfs4_sops;
2040         nfs_initialise_sb(sb);
2041 }
2042
2043 /*
2044  * Validate NFSv4 mount options
2045  */
2046 static int nfs4_validate_mount_data(void *options,
2047                                     struct nfs_parsed_mount_data *args,
2048                                     const char *dev_name)
2049 {
2050         struct sockaddr_in *ap;
2051         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2052         char *c;
2053
2054         if (data == NULL)
2055                 goto out_no_data;
2056
2057         args->rsize             = NFS_MAX_FILE_IO_SIZE;
2058         args->wsize             = NFS_MAX_FILE_IO_SIZE;
2059         args->timeo             = 600;
2060         args->retrans           = 2;
2061         args->acregmin          = 3;
2062         args->acregmax          = 60;
2063         args->acdirmin          = 30;
2064         args->acdirmax          = 60;
2065         args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
2066         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
2067
2068         switch (data->version) {
2069         case 1:
2070                 ap = (struct sockaddr_in *)&args->nfs_server.address;
2071                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2072                         goto out_no_address;
2073                 if (data->host_addrlen == 0)
2074                         goto out_no_address;
2075                 args->nfs_server.addrlen = data->host_addrlen;
2076                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
2077                         return -EFAULT;
2078                 if (!nfs_verify_server_address((struct sockaddr *)
2079                                                 &args->nfs_server.address))
2080                         goto out_no_address;
2081
2082                 switch (data->auth_flavourlen) {
2083                 case 0:
2084                         args->auth_flavors[0] = RPC_AUTH_UNIX;
2085                         break;
2086                 case 1:
2087                         if (copy_from_user(&args->auth_flavors[0],
2088                                            data->auth_flavours,
2089                                            sizeof(args->auth_flavors[0])))
2090                                 return -EFAULT;
2091                         break;
2092                 default:
2093                         goto out_inval_auth;
2094                 }
2095
2096                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2097                 if (IS_ERR(c))
2098                         return PTR_ERR(c);
2099                 args->nfs_server.hostname = c;
2100
2101                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2102                 if (IS_ERR(c))
2103                         return PTR_ERR(c);
2104                 args->nfs_server.export_path = c;
2105                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2106
2107                 c = strndup_user(data->client_addr.data, 16);
2108                 if (IS_ERR(c))
2109                         return PTR_ERR(c);
2110                 args->client_address = c;
2111
2112                 /*
2113                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2114                  * can deal with.
2115                  */
2116
2117                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2118                 args->rsize     = data->rsize;
2119                 args->wsize     = data->wsize;
2120                 args->timeo     = data->timeo;
2121                 args->retrans   = data->retrans;
2122                 args->acregmin  = data->acregmin;
2123                 args->acregmax  = data->acregmax;
2124                 args->acdirmin  = data->acdirmin;
2125                 args->acdirmax  = data->acdirmax;
2126                 args->nfs_server.protocol = data->proto;
2127
2128                 break;
2129         default: {
2130                 int status;
2131
2132                 if (nfs_parse_mount_options((char *)options, args) == 0)
2133                         return -EINVAL;
2134
2135                 if (!nfs_verify_server_address((struct sockaddr *)
2136                                                 &args->nfs_server.address))
2137                         return -EINVAL;
2138
2139                 switch (args->auth_flavor_len) {
2140                 case 0:
2141                         args->auth_flavors[0] = RPC_AUTH_UNIX;
2142                         break;
2143                 case 1:
2144                         break;
2145                 default:
2146                         goto out_inval_auth;
2147                 }
2148
2149                 if (args->client_address == NULL)
2150                         goto out_no_client_address;
2151
2152                 status = nfs_parse_devname(dev_name,
2153                                            &args->nfs_server.hostname,
2154                                            NFS4_MAXNAMLEN,
2155                                            &args->nfs_server.export_path,
2156                                            NFS4_MAXPATHLEN);
2157                 if (status < 0)
2158                         return status;
2159
2160                 break;
2161                 }
2162         }
2163
2164         return 0;
2165
2166 out_no_data:
2167         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2168         return -EINVAL;
2169
2170 out_inval_auth:
2171         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2172                  data->auth_flavourlen);
2173         return -EINVAL;
2174
2175 out_no_address:
2176         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2177         return -EINVAL;
2178
2179 out_no_client_address:
2180         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
2181         return -EINVAL;
2182 }
2183
2184 /*
2185  * Get the superblock for an NFS4 mountpoint
2186  */
2187 static int nfs4_get_sb(struct file_system_type *fs_type,
2188         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2189 {
2190         struct nfs_parsed_mount_data *data;
2191         struct super_block *s;
2192         struct nfs_server *server;
2193         struct nfs_fh *mntfh;
2194         struct dentry *mntroot;
2195         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2196         struct nfs_sb_mountdata sb_mntdata = {
2197                 .mntflags = flags,
2198         };
2199         int error = -ENOMEM;
2200
2201         data = kzalloc(sizeof(*data), GFP_KERNEL);
2202         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2203         if (data == NULL || mntfh == NULL)
2204                 goto out_free_fh;
2205
2206         security_init_mnt_opts(&data->lsm_opts);
2207
2208         /* Validate the mount data */
2209         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2210         if (error < 0)
2211                 goto out;
2212
2213         /* Get a volume representation */
2214         server = nfs4_create_server(data, mntfh);
2215         if (IS_ERR(server)) {
2216                 error = PTR_ERR(server);
2217                 goto out;
2218         }
2219         sb_mntdata.server = server;
2220
2221         if (server->flags & NFS4_MOUNT_UNSHARED)
2222                 compare_super = NULL;
2223
2224         /* Get a superblock - note that we may end up sharing one that already exists */
2225         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2226         if (IS_ERR(s)) {
2227                 error = PTR_ERR(s);
2228                 goto out_free;
2229         }
2230
2231         if (s->s_fs_info != server) {
2232                 nfs_free_server(server);
2233                 server = NULL;
2234         } else {
2235                 error = nfs_bdi_register(server);
2236                 if (error)
2237                         goto error_splat_super;
2238         }
2239
2240         if (!s->s_root) {
2241                 /* initial superblock/root creation */
2242                 nfs4_fill_super(s);
2243         }
2244
2245         mntroot = nfs4_get_root(s, mntfh);
2246         if (IS_ERR(mntroot)) {
2247                 error = PTR_ERR(mntroot);
2248                 goto error_splat_super;
2249         }
2250
2251         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2252         if (error)
2253                 goto error_splat_root;
2254
2255         s->s_flags |= MS_ACTIVE;
2256         mnt->mnt_sb = s;
2257         mnt->mnt_root = mntroot;
2258         error = 0;
2259
2260 out:
2261         kfree(data->client_address);
2262         kfree(data->nfs_server.export_path);
2263         kfree(data->nfs_server.hostname);
2264         security_free_mnt_opts(&data->lsm_opts);
2265 out_free_fh:
2266         kfree(mntfh);
2267         kfree(data);
2268         return error;
2269
2270 out_free:
2271         nfs_free_server(server);
2272         goto out;
2273
2274 error_splat_root:
2275         dput(mntroot);
2276 error_splat_super:
2277         up_write(&s->s_umount);
2278         deactivate_super(s);
2279         goto out;
2280 }
2281
2282 static void nfs4_kill_super(struct super_block *sb)
2283 {
2284         struct nfs_server *server = NFS_SB(sb);
2285
2286         nfs_return_all_delegations(sb);
2287         kill_anon_super(sb);
2288
2289         nfs4_renewd_prepare_shutdown(server);
2290         nfs_free_server(server);
2291 }
2292
2293 /*
2294  * Clone an NFS4 server record on xdev traversal (FSID-change)
2295  */
2296 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2297                             const char *dev_name, void *raw_data,
2298                             struct vfsmount *mnt)
2299 {
2300         struct nfs_clone_mount *data = raw_data;
2301         struct super_block *s;
2302         struct nfs_server *server;
2303         struct dentry *mntroot;
2304         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2305         struct nfs_sb_mountdata sb_mntdata = {
2306                 .mntflags = flags,
2307         };
2308         int error;
2309
2310         dprintk("--> nfs4_xdev_get_sb()\n");
2311
2312         /* create a new volume representation */
2313         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2314         if (IS_ERR(server)) {
2315                 error = PTR_ERR(server);
2316                 goto out_err_noserver;
2317         }
2318         sb_mntdata.server = server;
2319
2320         if (server->flags & NFS4_MOUNT_UNSHARED)
2321                 compare_super = NULL;
2322
2323         /* Get a superblock - note that we may end up sharing one that already exists */
2324         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2325         if (IS_ERR(s)) {
2326                 error = PTR_ERR(s);
2327                 goto out_err_nosb;
2328         }
2329
2330         if (s->s_fs_info != server) {
2331                 nfs_free_server(server);
2332                 server = NULL;
2333         } else {
2334                 error = nfs_bdi_register(server);
2335                 if (error)
2336                         goto error_splat_super;
2337         }
2338
2339         if (!s->s_root) {
2340                 /* initial superblock/root creation */
2341                 nfs4_clone_super(s, data->sb);
2342         }
2343
2344         mntroot = nfs4_get_root(s, data->fh);
2345         if (IS_ERR(mntroot)) {
2346                 error = PTR_ERR(mntroot);
2347                 goto error_splat_super;
2348         }
2349         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2350                 dput(mntroot);
2351                 error = -ESTALE;
2352                 goto error_splat_super;
2353         }
2354
2355         s->s_flags |= MS_ACTIVE;
2356         mnt->mnt_sb = s;
2357         mnt->mnt_root = mntroot;
2358
2359         security_sb_clone_mnt_opts(data->sb, s);
2360
2361         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2362         return 0;
2363
2364 out_err_nosb:
2365         nfs_free_server(server);
2366 out_err_noserver:
2367         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2368         return error;
2369
2370 error_splat_super:
2371         up_write(&s->s_umount);
2372         deactivate_super(s);
2373         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2374         return error;
2375 }
2376
2377 /*
2378  * Create an NFS4 server record on referral traversal
2379  */
2380 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2381                                 const char *dev_name, void *raw_data,
2382                                 struct vfsmount *mnt)
2383 {
2384         struct nfs_clone_mount *data = raw_data;
2385         struct super_block *s;
2386         struct nfs_server *server;
2387         struct dentry *mntroot;
2388         struct nfs_fh mntfh;
2389         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2390         struct nfs_sb_mountdata sb_mntdata = {
2391                 .mntflags = flags,
2392         };
2393         int error;
2394
2395         dprintk("--> nfs4_referral_get_sb()\n");
2396
2397         /* create a new volume representation */
2398         server = nfs4_create_referral_server(data, &mntfh);
2399         if (IS_ERR(server)) {
2400                 error = PTR_ERR(server);
2401                 goto out_err_noserver;
2402         }
2403         sb_mntdata.server = server;
2404
2405         if (server->flags & NFS4_MOUNT_UNSHARED)
2406                 compare_super = NULL;
2407
2408         /* Get a superblock - note that we may end up sharing one that already exists */
2409         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2410         if (IS_ERR(s)) {
2411                 error = PTR_ERR(s);
2412                 goto out_err_nosb;
2413         }
2414
2415         if (s->s_fs_info != server) {
2416                 nfs_free_server(server);
2417                 server = NULL;
2418         } else {
2419                 error = nfs_bdi_register(server);
2420                 if (error)
2421                         goto error_splat_super;
2422         }
2423
2424         if (!s->s_root) {
2425                 /* initial superblock/root creation */
2426                 nfs4_fill_super(s);
2427         }
2428
2429         mntroot = nfs4_get_root(s, &mntfh);
2430         if (IS_ERR(mntroot)) {
2431                 error = PTR_ERR(mntroot);
2432                 goto error_splat_super;
2433         }
2434         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2435                 dput(mntroot);
2436                 error = -ESTALE;
2437                 goto error_splat_super;
2438         }
2439
2440         s->s_flags |= MS_ACTIVE;
2441         mnt->mnt_sb = s;
2442         mnt->mnt_root = mntroot;
2443
2444         security_sb_clone_mnt_opts(data->sb, s);
2445
2446         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2447         return 0;
2448
2449 out_err_nosb:
2450         nfs_free_server(server);
2451 out_err_noserver:
2452         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2453         return error;
2454
2455 error_splat_super:
2456         up_write(&s->s_umount);
2457         deactivate_super(s);
2458         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2459         return error;
2460 }
2461
2462 #endif /* CONFIG_NFS_V4 */