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   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/smp_lock.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <net/ipv6.h>
  50 #include <linux/nfs_xdr.h>
  51 #include <linux/magic.h>
  52 #include <linux/parser.h>
  53
  54 #include <asm/system.h>
  55 #include <asm/uaccess.h>
  56
  57 #include "nfs4_fs.h"
  58 #include "callback.h"
  59 #include "delegation.h"
  60 #include "iostat.h"
  61 #include "internal.h"
  62
  63 #define NFSDBG_FACILITY         NFSDBG_VFS
  64
  65 enum {
  66         /* Mount options that take no arguments */
  67         Opt_soft, Opt_hard,
  68         Opt_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 /*
 709  * Parse string addresses passed in via a mount option,
 710  * and construct a sockaddr based on the result.
 711  *
 712  * If address parsing fails, set the sockaddr's address
 713  * family to AF_UNSPEC to force nfs_verify_server_address()
 714  * to punt the mount.
 715  */
 716 static void nfs_parse_server_address(char *value,
 717                                      struct sockaddr *sap,
 718                                      size_t *len)
 719 {
 720         if (strchr(value, ':')) {
 721                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 722                 u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
 723
 724                 ap->sin6_family = AF_INET6;
 725                 *len = sizeof(*ap);
 726                 if (in6_pton(value, -1, addr, '\0', NULL))
 727                         return;
 728         } else {
 729                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 730                 u8 *addr = (u8 *)&ap->sin_addr.s_addr;
 731
 732                 ap->sin_family = AF_INET;
 733                 *len = sizeof(*ap);
 734                 if (in4_pton(value, -1, addr, '\0', NULL))
 735                         return;
 736         }
 737
 738         sap->sa_family = AF_UNSPEC;
 739         *len = 0;
 740 }
 741
 742 /*
 743  * Error-check and convert a string of mount options from user space into
 744  * a data structure
 745  */
 746 static int nfs_parse_mount_options(char *raw,
 747                                    struct nfs_parsed_mount_data *mnt)
 748 {
 749         char *p, *string, *secdata;
 750         int rc;
 751
 752         if (!raw) {
 753                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 754                 return 1;
 755         }
 756         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 757
 758         secdata = alloc_secdata();
 759         if (!secdata)
 760                 goto out_nomem;
 761
 762         rc = security_sb_copy_data(raw, secdata);
 763         if (rc)
 764                 goto out_security_failure;
 765
 766         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 767         if (rc)
 768                 goto out_security_failure;
 769
 770         free_secdata(secdata);
 771
 772         while ((p = strsep(&raw, ",")) != NULL) {
 773                 substring_t args[MAX_OPT_ARGS];
 774                 int option, token;
 775
 776                 if (!*p)
 777                         continue;
 778
 779                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 780
 781                 token = match_token(p, nfs_mount_option_tokens, args);
 782                 switch (token) {
 783                 case Opt_soft:
 784                         mnt->flags |= NFS_MOUNT_SOFT;
 785                         break;
 786                 case Opt_hard:
 787                         mnt->flags &= ~NFS_MOUNT_SOFT;
 788                         break;
 789                 case Opt_posix:
 790                         mnt->flags |= NFS_MOUNT_POSIX;
 791                         break;
 792                 case Opt_noposix:
 793                         mnt->flags &= ~NFS_MOUNT_POSIX;
 794                         break;
 795                 case Opt_cto:
 796                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 797                         break;
 798                 case Opt_nocto:
 799                         mnt->flags |= NFS_MOUNT_NOCTO;
 800                         break;
 801                 case Opt_ac:
 802                         mnt->flags &= ~NFS_MOUNT_NOAC;
 803                         break;
 804                 case Opt_noac:
 805                         mnt->flags |= NFS_MOUNT_NOAC;
 806                         break;
 807                 case Opt_lock:
 808                         mnt->flags &= ~NFS_MOUNT_NONLM;
 809                         break;
 810                 case Opt_nolock:
 811                         mnt->flags |= NFS_MOUNT_NONLM;
 812                         break;
 813                 case Opt_v2:
 814                         mnt->flags &= ~NFS_MOUNT_VER3;
 815                         break;
 816                 case Opt_v3:
 817                         mnt->flags |= NFS_MOUNT_VER3;
 818                         break;
 819                 case Opt_udp:
 820                         mnt->flags &= ~NFS_MOUNT_TCP;
 821                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 822                         mnt->timeo = 7;
 823                         mnt->retrans = 5;
 824                         break;
 825                 case Opt_tcp:
 826                         mnt->flags |= NFS_MOUNT_TCP;
 827                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 828                         mnt->timeo = 600;
 829                         mnt->retrans = 2;
 830                         break;
 831                 case Opt_rdma:
 832                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 833                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 834                         mnt->timeo = 600;
 835                         mnt->retrans = 2;
 836                         break;
 837                 case Opt_acl:
 838                         mnt->flags &= ~NFS_MOUNT_NOACL;
 839                         break;
 840                 case Opt_noacl:
 841                         mnt->flags |= NFS_MOUNT_NOACL;
 842                         break;
 843                 case Opt_rdirplus:
 844                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 845                         break;
 846                 case Opt_nordirplus:
 847                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 848                         break;
 849                 case Opt_sharecache:
 850                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 851                         break;
 852                 case Opt_nosharecache:
 853                         mnt->flags |= NFS_MOUNT_UNSHARED;
 854                         break;
 855
 856                 case Opt_port:
 857                         if (match_int(args, &option))
 858                                 return 0;
 859                         if (option < 0 || option > 65535)
 860                                 return 0;
 861                         mnt->nfs_server.port = option;
 862                         break;
 863                 case Opt_rsize:
 864                         if (match_int(args, &mnt->rsize))
 865                                 return 0;
 866                         break;
 867                 case Opt_wsize:
 868                         if (match_int(args, &mnt->wsize))
 869                                 return 0;
 870                         break;
 871                 case Opt_bsize:
 872                         if (match_int(args, &option))
 873                                 return 0;
 874                         if (option < 0)
 875                                 return 0;
 876                         mnt->bsize = option;
 877                         break;
 878                 case Opt_timeo:
 879                         if (match_int(args, &mnt->timeo))
 880                                 return 0;
 881                         break;
 882                 case Opt_retrans:
 883                         if (match_int(args, &mnt->retrans))
 884                                 return 0;
 885                         break;
 886                 case Opt_acregmin:
 887                         if (match_int(args, &mnt->acregmin))
 888                                 return 0;
 889                         break;
 890                 case Opt_acregmax:
 891                         if (match_int(args, &mnt->acregmax))
 892                                 return 0;
 893                         break;
 894                 case Opt_acdirmin:
 895                         if (match_int(args, &mnt->acdirmin))
 896                                 return 0;
 897                         break;
 898                 case Opt_acdirmax:
 899                         if (match_int(args, &mnt->acdirmax))
 900                                 return 0;
 901                         break;
 902                 case Opt_actimeo:
 903                         if (match_int(args, &option))
 904                                 return 0;
 905                         if (option < 0)
 906                                 return 0;
 907                         mnt->acregmin =
 908                         mnt->acregmax =
 909                         mnt->acdirmin =
 910                         mnt->acdirmax = option;
 911                         break;
 912                 case Opt_namelen:
 913                         if (match_int(args, &mnt->namlen))
 914                                 return 0;
 915                         break;
 916                 case Opt_mountport:
 917                         if (match_int(args, &option))
 918                                 return 0;
 919                         if (option < 0 || option > 65535)
 920                                 return 0;
 921                         mnt->mount_server.port = option;
 922                         break;
 923                 case Opt_mountvers:
 924                         if (match_int(args, &option))
 925                                 return 0;
 926                         if (option < 0)
 927                                 return 0;
 928                         mnt->mount_server.version = option;
 929                         break;
 930                 case Opt_nfsvers:
 931                         if (match_int(args, &option))
 932                                 return 0;
 933                         switch (option) {
 934                         case 2:
 935                                 mnt->flags &= ~NFS_MOUNT_VER3;
 936                                 break;
 937                         case 3:
 938                                 mnt->flags |= NFS_MOUNT_VER3;
 939                                 break;
 940                         default:
 941                                 goto out_unrec_vers;
 942                         }
 943                         break;
 944
 945                 case Opt_sec:
 946                         string = match_strdup(args);
 947                         if (string == NULL)
 948                                 goto out_nomem;
 949                         token = match_token(string, nfs_secflavor_tokens, args);
 950                         kfree(string);
 951
 952                         /*
 953                          * The flags setting is for v2/v3.  The flavor_len
 954                          * setting is for v4.  v2/v3 also need to know the
 955                          * difference between NULL and UNIX.
 956                          */
 957                         switch (token) {
 958                         case Opt_sec_none:
 959                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 960                                 mnt->auth_flavor_len = 0;
 961                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 962                                 break;
 963                         case Opt_sec_sys:
 964                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 965                                 mnt->auth_flavor_len = 0;
 966                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 967                                 break;
 968                         case Opt_sec_krb5:
 969                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 970                                 mnt->auth_flavor_len = 1;
 971                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 972                                 break;
 973                         case Opt_sec_krb5i:
 974                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 975                                 mnt->auth_flavor_len = 1;
 976                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 977                                 break;
 978                         case Opt_sec_krb5p:
 979                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 980                                 mnt->auth_flavor_len = 1;
 981                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 982                                 break;
 983                         case Opt_sec_lkey:
 984                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 985                                 mnt->auth_flavor_len = 1;
 986                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 987                                 break;
 988                         case Opt_sec_lkeyi:
 989                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 990                                 mnt->auth_flavor_len = 1;
 991                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 992                                 break;
 993                         case Opt_sec_lkeyp:
 994                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 995                                 mnt->auth_flavor_len = 1;
 996                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 997                                 break;
 998                         case Opt_sec_spkm:
 999                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1000                                 mnt->auth_flavor_len = 1;
1001                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1002                                 break;
1003                         case Opt_sec_spkmi:
1004                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1005                                 mnt->auth_flavor_len = 1;
1006                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1007                                 break;
1008                         case Opt_sec_spkmp:
1009                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1010                                 mnt->auth_flavor_len = 1;
1011                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1012                                 break;
1013                         default:
1014                                 goto out_unrec_sec;
1015                         }
1016                         break;
1017                 case Opt_proto:
1018                         string = match_strdup(args);
1019                         if (string == NULL)
1020                                 goto out_nomem;
1021                         token = match_token(string,
1022                                             nfs_xprt_protocol_tokens, args);
1023                         kfree(string);
1024
1025                         switch (token) {
1026                         case Opt_xprt_udp:
1027                                 mnt->flags &= ~NFS_MOUNT_TCP;
1028                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1029                                 mnt->timeo = 7;
1030                                 mnt->retrans = 5;
1031                                 break;
1032                         case Opt_xprt_tcp:
1033                                 mnt->flags |= NFS_MOUNT_TCP;
1034                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1035                                 mnt->timeo = 600;
1036                                 mnt->retrans = 2;
1037                                 break;
1038                         case Opt_xprt_rdma:
1039                                 /* vector side protocols to TCP */
1040                                 mnt->flags |= NFS_MOUNT_TCP;
1041                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1042                                 mnt->timeo = 600;
1043                                 mnt->retrans = 2;
1044                                 break;
1045                         default:
1046                                 goto out_unrec_xprt;
1047                         }
1048                         break;
1049                 case Opt_mountproto:
1050                         string = match_strdup(args);
1051                         if (string == NULL)
1052                                 goto out_nomem;
1053                         token = match_token(string,
1054                                             nfs_xprt_protocol_tokens, args);
1055                         kfree(string);
1056
1057                         switch (token) {
1058                         case Opt_xprt_udp:
1059                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1060                                 break;
1061                         case Opt_xprt_tcp:
1062                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1063                                 break;
1064                         case Opt_xprt_rdma: /* not used for side protocols */
1065                         default:
1066                                 goto out_unrec_xprt;
1067                         }
1068                         break;
1069                 case Opt_addr:
1070                         string = match_strdup(args);
1071                         if (string == NULL)
1072                                 goto out_nomem;
1073                         nfs_parse_server_address(string, (struct sockaddr *)
1074                                                  &mnt->nfs_server.address,
1075                                                  &mnt->nfs_server.addrlen);
1076                         kfree(string);
1077                         break;
1078                 case Opt_clientaddr:
1079                         string = match_strdup(args);
1080                         if (string == NULL)
1081                                 goto out_nomem;
1082                         kfree(mnt->client_address);
1083                         mnt->client_address = string;
1084                         break;
1085                 case Opt_mounthost:
1086                         string = match_strdup(args);
1087                         if (string == NULL)
1088                                 goto out_nomem;
1089                         kfree(mnt->mount_server.hostname);
1090                         mnt->mount_server.hostname = string;
1091                         break;
1092                 case Opt_mountaddr:
1093                         string = match_strdup(args);
1094                         if (string == NULL)
1095                                 goto out_nomem;
1096                         nfs_parse_server_address(string, (struct sockaddr *)
1097                                                  &mnt->mount_server.address,
1098                                                  &mnt->mount_server.addrlen);
1099                         kfree(string);
1100                         break;
1101
1102                 case Opt_userspace:
1103                 case Opt_deprecated:
1104                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1105                                         "'%s'\n", p);
1106                         break;
1107
1108                 default:
1109                         goto out_unknown;
1110                 }
1111         }
1112
1113         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
1114                                 mnt->nfs_server.port);
1115
1116         return 1;
1117
1118 out_nomem:
1119         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1120         return 0;
1121 out_security_failure:
1122         free_secdata(secdata);
1123         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1124         return 0;
1125 out_unrec_vers:
1126         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1127         return 0;
1128
1129 out_unrec_xprt:
1130         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1131         return 0;
1132
1133 out_unrec_sec:
1134         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1135         return 0;
1136
1137 out_unknown:
1138         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1139         return 0;
1140 }
1141
1142 /*
1143  * Use the remote server's MOUNT service to request the NFS file handle
1144  * corresponding to the provided path.
1145  */
1146 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1147                          struct nfs_fh *root_fh)
1148 {
1149         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1150         char *hostname;
1151         int status;
1152
1153         if (args->mount_server.version == 0) {
1154                 if (args->flags & NFS_MOUNT_VER3)
1155                         args->mount_server.version = NFS_MNT3_VERSION;
1156                 else
1157                         args->mount_server.version = NFS_MNT_VERSION;
1158         }
1159
1160         if (args->mount_server.hostname)
1161                 hostname = args->mount_server.hostname;
1162         else
1163                 hostname = args->nfs_server.hostname;
1164
1165         /*
1166          * Construct the mount server's address.
1167          */
1168         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1169                 memcpy(sap, &args->nfs_server.address,
1170                        args->nfs_server.addrlen);
1171                 args->mount_server.addrlen = args->nfs_server.addrlen;
1172         }
1173
1174         /*
1175          * autobind will be used if mount_server.port == 0
1176          */
1177         nfs_set_port(sap, args->mount_server.port);
1178
1179         /*
1180          * Now ask the mount server to map our export path
1181          * to a file handle.
1182          */
1183         status = nfs_mount(sap,
1184                            args->mount_server.addrlen,
1185                            hostname,
1186                            args->nfs_server.export_path,
1187                            args->mount_server.version,
1188                            args->mount_server.protocol,
1189                            root_fh);
1190         if (status == 0)
1191                 return 0;
1192
1193         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1194                         hostname, status);
1195         return status;
1196 }
1197
1198 /*
1199  * Split "dev_name" into "hostname:export_path".
1200  *
1201  * Note: caller frees hostname and export path, even on error.
1202  */
1203 static int nfs_parse_devname(const char *dev_name,
1204                              char **hostname, size_t maxnamlen,
1205                              char **export_path, size_t maxpathlen)
1206 {
1207         size_t len;
1208         char *colon, *comma;
1209
1210         colon = strchr(dev_name, ':');
1211         if (colon == NULL)
1212                 goto out_bad_devname;
1213
1214         len = colon - dev_name;
1215         if (len > maxnamlen)
1216                 goto out_hostname;
1217
1218         /* N.B. caller will free nfs_server.hostname in all cases */
1219         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1220         if (!*hostname)
1221                 goto out_nomem;
1222
1223         /* kill possible hostname list: not supported */
1224         comma = strchr(*hostname, ',');
1225         if (comma != NULL) {
1226                 if (comma == *hostname)
1227                         goto out_bad_devname;
1228                 *comma = '\0';
1229         }
1230
1231         colon++;
1232         len = strlen(colon);
1233         if (len > maxpathlen)
1234                 goto out_path;
1235         *export_path = kstrndup(colon, len, GFP_KERNEL);
1236         if (!*export_path)
1237                 goto out_nomem;
1238
1239         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1240         return 0;
1241
1242 out_bad_devname:
1243         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1244         return -EINVAL;
1245
1246 out_nomem:
1247         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1248         return -ENOMEM;
1249
1250 out_hostname:
1251         dfprintk(MOUNT, "NFS: server hostname too long\n");
1252         return -ENAMETOOLONG;
1253
1254 out_path:
1255         dfprintk(MOUNT, "NFS: export pathname too long\n");
1256         return -ENAMETOOLONG;
1257 }
1258
1259 /*
1260  * Validate the NFS2/NFS3 mount data
1261  * - fills in the mount root filehandle
1262  *
1263  * For option strings, user space handles the following behaviors:
1264  *
1265  * + DNS: mapping server host name to IP address ("addr=" option)
1266  *
1267  * + failure mode: how to behave if a mount request can't be handled
1268  *   immediately ("fg/bg" option)
1269  *
1270  * + retry: how often to retry a mount request ("retry=" option)
1271  *
1272  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1273  *   mountproto=tcp after mountproto=udp, and so on
1274  */
1275 static int nfs_validate_mount_data(void *options,
1276                                    struct nfs_parsed_mount_data *args,
1277                                    struct nfs_fh *mntfh,
1278                                    const char *dev_name)
1279 {
1280         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1281
1282         if (data == NULL)
1283                 goto out_no_data;
1284
1285         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1286         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1287         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1288         args->timeo             = 600;
1289         args->retrans           = 2;
1290         args->acregmin          = 3;
1291         args->acregmax          = 60;
1292         args->acdirmin          = 30;
1293         args->acdirmax          = 60;
1294         args->mount_server.port = 0;    /* autobind unless user sets port */
1295         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1296         args->nfs_server.port   = 0;    /* autobind unless user sets port */
1297         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1298
1299         switch (data->version) {
1300         case 1:
1301                 data->namlen = 0;
1302         case 2:
1303                 data->bsize = 0;
1304         case 3:
1305                 if (data->flags & NFS_MOUNT_VER3)
1306                         goto out_no_v3;
1307                 data->root.size = NFS2_FHSIZE;
1308                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1309         case 4:
1310                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1311                         goto out_no_sec;
1312         case 5:
1313                 memset(data->context, 0, sizeof(data->context));
1314         case 6:
1315                 if (data->flags & NFS_MOUNT_VER3) {
1316                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1317                                 goto out_invalid_fh;
1318                         mntfh->size = data->root.size;
1319                 } else
1320                         mntfh->size = NFS2_FHSIZE;
1321
1322
1323                 memcpy(mntfh->data, data->root.data, mntfh->size);
1324                 if (mntfh->size < sizeof(mntfh->data))
1325                         memset(mntfh->data + mntfh->size, 0,
1326                                sizeof(mntfh->data) - mntfh->size);
1327
1328                 /*
1329                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1330                  * can deal with.
1331                  */
1332                 args->flags             = data->flags;
1333                 args->rsize             = data->rsize;
1334                 args->wsize             = data->wsize;
1335                 args->timeo             = data->timeo;
1336                 args->retrans           = data->retrans;
1337                 args->acregmin          = data->acregmin;
1338                 args->acregmax          = data->acregmax;
1339                 args->acdirmin          = data->acdirmin;
1340                 args->acdirmax          = data->acdirmax;
1341
1342                 memcpy(&args->nfs_server.address, &data->addr,
1343                        sizeof(data->addr));
1344                 args->nfs_server.addrlen = sizeof(data->addr);
1345                 if (!nfs_verify_server_address((struct sockaddr *)
1346                                                 &args->nfs_server.address))
1347                         goto out_no_address;
1348
1349                 if (!(data->flags & NFS_MOUNT_TCP))
1350                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1351                 /* N.B. caller will free nfs_server.hostname in all cases */
1352                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1353                 args->namlen            = data->namlen;
1354                 args->bsize             = data->bsize;
1355                 args->auth_flavors[0]   = data->pseudoflavor;
1356                 if (!args->nfs_server.hostname)
1357                         goto out_nomem;
1358
1359                 /*
1360                  * The legacy version 6 binary mount data from userspace has a
1361                  * field used only to transport selinux information into the
1362                  * the kernel.  To continue to support that functionality we
1363                  * have a touch of selinux knowledge here in the NFS code. The
1364                  * userspace code converted context=blah to just blah so we are
1365                  * converting back to the full string selinux understands.
1366                  */
1367                 if (data->context[0]){
1368 #ifdef CONFIG_SECURITY_SELINUX
1369                         int rc;
1370                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1371                         if (!opts_str)
1372                                 return -ENOMEM;
1373                         strcpy(opts_str, "context=");
1374                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1375                         strcat(opts_str, &data->context[0]);
1376                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1377                         kfree(opts_str);
1378                         if (rc)
1379                                 return rc;
1380 #else
1381                         return -EINVAL;
1382 #endif
1383                 }
1384
1385                 break;
1386         default: {
1387                 int status;
1388
1389                 if (nfs_parse_mount_options((char *)options, args) == 0)
1390                         return -EINVAL;
1391
1392                 if (!nfs_verify_server_address((struct sockaddr *)
1393                                                 &args->nfs_server.address))
1394                         goto out_no_address;
1395
1396                 status = nfs_parse_devname(dev_name,
1397                                            &args->nfs_server.hostname,
1398                                            PAGE_SIZE,
1399                                            &args->nfs_server.export_path,
1400                                            NFS_MAXPATHLEN);
1401                 if (!status)
1402                         status = nfs_try_mount(args, mntfh);
1403
1404                 kfree(args->nfs_server.export_path);
1405                 args->nfs_server.export_path = NULL;
1406
1407                 if (status)
1408                         return status;
1409
1410                 break;
1411                 }
1412         }
1413
1414         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1415                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1416
1417 #ifndef CONFIG_NFS_V3
1418         if (args->flags & NFS_MOUNT_VER3)
1419                 goto out_v3_not_compiled;
1420 #endif /* !CONFIG_NFS_V3 */
1421
1422         return 0;
1423
1424 out_no_data:
1425         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1426         return -EINVAL;
1427
1428 out_no_v3:
1429         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1430                  data->version);
1431         return -EINVAL;
1432
1433 out_no_sec:
1434         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1435         return -EINVAL;
1436
1437 #ifndef CONFIG_NFS_V3
1438 out_v3_not_compiled:
1439         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1440         return -EPROTONOSUPPORT;
1441 #endif /* !CONFIG_NFS_V3 */
1442
1443 out_nomem:
1444         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1445         return -ENOMEM;
1446
1447 out_no_address:
1448         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1449         return -EINVAL;
1450
1451 out_invalid_fh:
1452         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1453         return -EINVAL;
1454 }
1455
1456 static int
1457 nfs_compare_remount_data(struct nfs_server *nfss,
1458                          struct nfs_parsed_mount_data *data)
1459 {
1460         if (data->flags != nfss->flags ||
1461             data->rsize != nfss->rsize ||
1462             data->wsize != nfss->wsize ||
1463             data->retrans != nfss->client->cl_timeout->to_retries ||
1464             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1465             data->acregmin != nfss->acregmin / HZ ||
1466             data->acregmax != nfss->acregmax / HZ ||
1467             data->acdirmin != nfss->acdirmin / HZ ||
1468             data->acdirmax != nfss->acdirmax / HZ ||
1469             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1470             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1471             memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1472                    data->nfs_server.addrlen) != 0)
1473                 return -EINVAL;
1474
1475         return 0;
1476 }
1477
1478 static int
1479 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1480 {
1481         int error;
1482         struct nfs_server *nfss = sb->s_fs_info;
1483         struct nfs_parsed_mount_data *data;
1484         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1485         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1486         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1487
1488         /*
1489          * Userspace mount programs that send binary options generally send
1490          * them populated with default values. We have no way to know which
1491          * ones were explicitly specified. Fall back to legacy behavior and
1492          * just return success.
1493          */
1494         if ((nfsvers == 4 && options4->version == 1) ||
1495             (nfsvers <= 3 && options->version >= 1 &&
1496              options->version <= 6))
1497                 return 0;
1498
1499         data = kzalloc(sizeof(*data), GFP_KERNEL);
1500         if (data == NULL)
1501                 return -ENOMEM;
1502
1503         /* fill out struct with values from existing mount */
1504         data->flags = nfss->flags;
1505         data->rsize = nfss->rsize;
1506         data->wsize = nfss->wsize;
1507         data->retrans = nfss->client->cl_timeout->to_retries;
1508         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1509         data->acregmin = nfss->acregmin / HZ;
1510         data->acregmax = nfss->acregmax / HZ;
1511         data->acdirmin = nfss->acdirmin / HZ;
1512         data->acdirmax = nfss->acdirmax / HZ;
1513         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1514         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1515         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1516                 data->nfs_server.addrlen);
1517
1518         /* overwrite those values with any that were specified */
1519         error = nfs_parse_mount_options((char *)options, data);
1520         if (error < 0)
1521                 goto out;
1522
1523         /* compare new mount options with old ones */
1524         error = nfs_compare_remount_data(nfss, data);
1525 out:
1526         kfree(data);
1527         return error;
1528 }
1529
1530 /*
1531  * Initialise the common bits of the superblock
1532  */
1533 static inline void nfs_initialise_sb(struct super_block *sb)
1534 {
1535         struct nfs_server *server = NFS_SB(sb);
1536
1537         sb->s_magic = NFS_SUPER_MAGIC;
1538
1539         /* We probably want something more informative here */
1540         snprintf(sb->s_id, sizeof(sb->s_id),
1541                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1542
1543         if (sb->s_blocksize == 0)
1544                 sb->s_blocksize = nfs_block_bits(server->wsize,
1545                                                  &sb->s_blocksize_bits);
1546
1547         if (server->flags & NFS_MOUNT_NOAC)
1548                 sb->s_flags |= MS_SYNCHRONOUS;
1549
1550         nfs_super_set_maxbytes(sb, server->maxfilesize);
1551 }
1552
1553 /*
1554  * Finish setting up an NFS2/3 superblock
1555  */
1556 static void nfs_fill_super(struct super_block *sb,
1557                            struct nfs_parsed_mount_data *data)
1558 {
1559         struct nfs_server *server = NFS_SB(sb);
1560
1561         sb->s_blocksize_bits = 0;
1562         sb->s_blocksize = 0;
1563         if (data->bsize)
1564                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1565
1566         if (server->flags & NFS_MOUNT_VER3) {
1567                 /* The VFS shouldn't apply the umask to mode bits. We will do
1568                  * so ourselves when necessary.
1569                  */
1570                 sb->s_flags |= MS_POSIXACL;
1571                 sb->s_time_gran = 1;
1572         }
1573
1574         sb->s_op = &nfs_sops;
1575         nfs_initialise_sb(sb);
1576 }
1577
1578 /*
1579  * Finish setting up a cloned NFS2/3 superblock
1580  */
1581 static void nfs_clone_super(struct super_block *sb,
1582                             const struct super_block *old_sb)
1583 {
1584         struct nfs_server *server = NFS_SB(sb);
1585
1586         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1587         sb->s_blocksize = old_sb->s_blocksize;
1588         sb->s_maxbytes = old_sb->s_maxbytes;
1589
1590         if (server->flags & NFS_MOUNT_VER3) {
1591                 /* The VFS shouldn't apply the umask to mode bits. We will do
1592                  * so ourselves when necessary.
1593                  */
1594                 sb->s_flags |= MS_POSIXACL;
1595                 sb->s_time_gran = 1;
1596         }
1597
1598         sb->s_op = old_sb->s_op;
1599         nfs_initialise_sb(sb);
1600 }
1601
1602 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1603
1604 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1605 {
1606         const struct nfs_server *a = s->s_fs_info;
1607         const struct rpc_clnt *clnt_a = a->client;
1608         const struct rpc_clnt *clnt_b = b->client;
1609
1610         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1611                 goto Ebusy;
1612         if (a->nfs_client != b->nfs_client)
1613                 goto Ebusy;
1614         if (a->flags != b->flags)
1615                 goto Ebusy;
1616         if (a->wsize != b->wsize)
1617                 goto Ebusy;
1618         if (a->rsize != b->rsize)
1619                 goto Ebusy;
1620         if (a->acregmin != b->acregmin)
1621                 goto Ebusy;
1622         if (a->acregmax != b->acregmax)
1623                 goto Ebusy;
1624         if (a->acdirmin != b->acdirmin)
1625                 goto Ebusy;
1626         if (a->acdirmax != b->acdirmax)
1627                 goto Ebusy;
1628         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1629                 goto Ebusy;
1630         return 1;
1631 Ebusy:
1632         return 0;
1633 }
1634
1635 struct nfs_sb_mountdata {
1636         struct nfs_server *server;
1637         int mntflags;
1638 };
1639
1640 static int nfs_set_super(struct super_block *s, void *data)
1641 {
1642         struct nfs_sb_mountdata *sb_mntdata = data;
1643         struct nfs_server *server = sb_mntdata->server;
1644         int ret;
1645
1646         s->s_flags = sb_mntdata->mntflags;
1647         s->s_fs_info = server;
1648         ret = set_anon_super(s, server);
1649         if (ret == 0)
1650                 server->s_dev = s->s_dev;
1651         return ret;
1652 }
1653
1654 static int nfs_compare_super_address(struct nfs_server *server1,
1655                                      struct nfs_server *server2)
1656 {
1657         struct sockaddr *sap1, *sap2;
1658
1659         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1660         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1661
1662         if (sap1->sa_family != sap2->sa_family)
1663                 return 0;
1664
1665         switch (sap1->sa_family) {
1666         case AF_INET: {
1667                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1668                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1669                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1670                         return 0;
1671                 if (sin1->sin_port != sin2->sin_port)
1672                         return 0;
1673                 break;
1674         }
1675         case AF_INET6: {
1676                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1677                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1678                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1679                         return 0;
1680                 if (sin1->sin6_port != sin2->sin6_port)
1681                         return 0;
1682                 break;
1683         }
1684         default:
1685                 return 0;
1686         }
1687
1688         return 1;
1689 }
1690
1691 static int nfs_compare_super(struct super_block *sb, void *data)
1692 {
1693         struct nfs_sb_mountdata *sb_mntdata = data;
1694         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1695         int mntflags = sb_mntdata->mntflags;
1696
1697         if (!nfs_compare_super_address(old, server))
1698                 return 0;
1699         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1700         if (old->flags & NFS_MOUNT_UNSHARED)
1701                 return 0;
1702         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1703                 return 0;
1704         return nfs_compare_mount_options(sb, server, mntflags);
1705 }
1706
1707 static int nfs_bdi_register(struct nfs_server *server)
1708 {
1709         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
1710 }
1711
1712 static int nfs_get_sb(struct file_system_type *fs_type,
1713         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1714 {
1715         struct nfs_server *server = NULL;
1716         struct super_block *s;
1717         struct nfs_parsed_mount_data *data;
1718         struct nfs_fh *mntfh;
1719         struct dentry *mntroot;
1720         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1721         struct nfs_sb_mountdata sb_mntdata = {
1722                 .mntflags = flags,
1723         };
1724         int error = -ENOMEM;
1725
1726         data = kzalloc(sizeof(*data), GFP_KERNEL);
1727         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
1728         if (data == NULL || mntfh == NULL)
1729                 goto out_free_fh;
1730
1731         security_init_mnt_opts(&data->lsm_opts);
1732
1733         /* Validate the mount data */
1734         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
1735         if (error < 0)
1736                 goto out;
1737
1738         /* Get a volume representation */
1739         server = nfs_create_server(data, mntfh);
1740         if (IS_ERR(server)) {
1741                 error = PTR_ERR(server);
1742                 goto out;
1743         }
1744         sb_mntdata.server = server;
1745
1746         if (server->flags & NFS_MOUNT_UNSHARED)
1747                 compare_super = NULL;
1748
1749         /* Get a superblock - note that we may end up sharing one that already exists */
1750         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1751         if (IS_ERR(s)) {
1752                 error = PTR_ERR(s);
1753                 goto out_err_nosb;
1754         }
1755
1756         if (s->s_fs_info != server) {
1757                 nfs_free_server(server);
1758                 server = NULL;
1759         } else {
1760                 error = nfs_bdi_register(server);
1761                 if (error)
1762                         goto error_splat_super;
1763         }
1764
1765         if (!s->s_root) {
1766                 /* initial superblock/root creation */
1767                 nfs_fill_super(s, data);
1768         }
1769
1770         mntroot = nfs_get_root(s, mntfh);
1771         if (IS_ERR(mntroot)) {
1772                 error = PTR_ERR(mntroot);
1773                 goto error_splat_super;
1774         }
1775
1776         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
1777         if (error)
1778                 goto error_splat_root;
1779
1780         s->s_flags |= MS_ACTIVE;
1781         mnt->mnt_sb = s;
1782         mnt->mnt_root = mntroot;
1783         error = 0;
1784
1785 out:
1786         kfree(data->nfs_server.hostname);
1787         kfree(data->mount_server.hostname);
1788         security_free_mnt_opts(&data->lsm_opts);
1789 out_free_fh:
1790         kfree(mntfh);
1791         kfree(data);
1792         return error;
1793
1794 out_err_nosb:
1795         nfs_free_server(server);
1796         goto out;
1797
1798 error_splat_root:
1799         dput(mntroot);
1800 error_splat_super:
1801         up_write(&s->s_umount);
1802         deactivate_super(s);
1803         goto out;
1804 }
1805
1806 /*
1807  * Destroy an NFS2/3 superblock
1808  */
1809 static void nfs_kill_super(struct super_block *s)
1810 {
1811         struct nfs_server *server = NFS_SB(s);
1812
1813         bdi_unregister(&server->backing_dev_info);
1814         kill_anon_super(s);
1815         nfs_free_server(server);
1816 }
1817
1818 /*
1819  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1820  */
1821 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1822                            const char *dev_name, void *raw_data,
1823                            struct vfsmount *mnt)
1824 {
1825         struct nfs_clone_mount *data = raw_data;
1826         struct super_block *s;
1827         struct nfs_server *server;
1828         struct dentry *mntroot;
1829         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1830         struct nfs_sb_mountdata sb_mntdata = {
1831                 .mntflags = flags,
1832         };
1833         int error;
1834
1835         dprintk("--> nfs_xdev_get_sb()\n");
1836
1837         /* create a new volume representation */
1838         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1839         if (IS_ERR(server)) {
1840                 error = PTR_ERR(server);
1841                 goto out_err_noserver;
1842         }
1843         sb_mntdata.server = server;
1844
1845         if (server->flags & NFS_MOUNT_UNSHARED)
1846                 compare_super = NULL;
1847
1848         /* Get a superblock - note that we may end up sharing one that already exists */
1849         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1850         if (IS_ERR(s)) {
1851                 error = PTR_ERR(s);
1852                 goto out_err_nosb;
1853         }
1854
1855         if (s->s_fs_info != server) {
1856                 nfs_free_server(server);
1857                 server = NULL;
1858         } else {
1859                 error = nfs_bdi_register(server);
1860                 if (error)
1861                         goto error_splat_super;
1862         }
1863
1864         if (!s->s_root) {
1865                 /* initial superblock/root creation */
1866                 nfs_clone_super(s, data->sb);
1867         }
1868
1869         mntroot = nfs_get_root(s, data->fh);
1870         if (IS_ERR(mntroot)) {
1871                 error = PTR_ERR(mntroot);
1872                 goto error_splat_super;
1873         }
1874         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1875                 dput(mntroot);
1876                 error = -ESTALE;
1877                 goto error_splat_super;
1878         }
1879
1880         s->s_flags |= MS_ACTIVE;
1881         mnt->mnt_sb = s;
1882         mnt->mnt_root = mntroot;
1883
1884         /* clone any lsm security options from the parent to the new sb */
1885         security_sb_clone_mnt_opts(data->sb, s);
1886
1887         dprintk("<-- nfs_xdev_get_sb() = 0\n");
1888         return 0;
1889
1890 out_err_nosb:
1891         nfs_free_server(server);
1892 out_err_noserver:
1893         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
1894         return error;
1895
1896 error_splat_super:
1897         up_write(&s->s_umount);
1898         deactivate_super(s);
1899         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
1900         return error;
1901 }
1902
1903 #ifdef CONFIG_NFS_V4
1904
1905 /*
1906  * Finish setting up a cloned NFS4 superblock
1907  */
1908 static void nfs4_clone_super(struct super_block *sb,
1909                             const struct super_block *old_sb)
1910 {
1911         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1912         sb->s_blocksize = old_sb->s_blocksize;
1913         sb->s_maxbytes = old_sb->s_maxbytes;
1914         sb->s_time_gran = 1;
1915         sb->s_op = old_sb->s_op;
1916         nfs_initialise_sb(sb);
1917 }
1918
1919 /*
1920  * Set up an NFS4 superblock
1921  */
1922 static void nfs4_fill_super(struct super_block *sb)
1923 {
1924         sb->s_time_gran = 1;
1925         sb->s_op = &nfs4_sops;
1926         nfs_initialise_sb(sb);
1927 }
1928
1929 /*
1930  * Validate NFSv4 mount options
1931  */
1932 static int nfs4_validate_mount_data(void *options,
1933                                     struct nfs_parsed_mount_data *args,
1934                                     const char *dev_name)
1935 {
1936         struct sockaddr_in *ap;
1937         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
1938         char *c;
1939
1940         if (data == NULL)
1941                 goto out_no_data;
1942
1943         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1944         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1945         args->timeo             = 600;
1946         args->retrans           = 2;
1947         args->acregmin          = 3;
1948         args->acregmax          = 60;
1949         args->acdirmin          = 30;
1950         args->acdirmax          = 60;
1951         args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
1952         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1953
1954         switch (data->version) {
1955         case 1:
1956                 ap = (struct sockaddr_in *)&args->nfs_server.address;
1957                 if (data->host_addrlen > sizeof(args->nfs_server.address))
1958                         goto out_no_address;
1959                 if (data->host_addrlen == 0)
1960                         goto out_no_address;
1961                 args->nfs_server.addrlen = data->host_addrlen;
1962                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
1963                         return -EFAULT;
1964                 if (!nfs_verify_server_address((struct sockaddr *)
1965                                                 &args->nfs_server.address))
1966                         goto out_no_address;
1967
1968                 switch (data->auth_flavourlen) {
1969                 case 0:
1970                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1971                         break;
1972                 case 1:
1973                         if (copy_from_user(&args->auth_flavors[0],
1974                                            data->auth_flavours,
1975                                            sizeof(args->auth_flavors[0])))
1976                                 return -EFAULT;
1977                         break;
1978                 default:
1979                         goto out_inval_auth;
1980                 }
1981
1982                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1983                 if (IS_ERR(c))
1984                         return PTR_ERR(c);
1985                 args->nfs_server.hostname = c;
1986
1987                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1988                 if (IS_ERR(c))
1989                         return PTR_ERR(c);
1990                 args->nfs_server.export_path = c;
1991                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1992
1993                 c = strndup_user(data->client_addr.data, 16);
1994                 if (IS_ERR(c))
1995                         return PTR_ERR(c);
1996                 args->client_address = c;
1997
1998                 /*
1999                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2000                  * can deal with.
2001                  */
2002
2003                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2004                 args->rsize     = data->rsize;
2005                 args->wsize     = data->wsize;
2006                 args->timeo     = data->timeo;
2007                 args->retrans   = data->retrans;
2008                 args->acregmin  = data->acregmin;
2009                 args->acregmax  = data->acregmax;
2010                 args->acdirmin  = data->acdirmin;
2011                 args->acdirmax  = data->acdirmax;
2012                 args->nfs_server.protocol = data->proto;
2013
2014                 break;
2015         default: {
2016                 int status;
2017
2018                 if (nfs_parse_mount_options((char *)options, args) == 0)
2019                         return -EINVAL;
2020
2021                 if (!nfs_verify_server_address((struct sockaddr *)
2022                                                 &args->nfs_server.address))
2023                         return -EINVAL;
2024
2025                 switch (args->auth_flavor_len) {
2026                 case 0:
2027                         args->auth_flavors[0] = RPC_AUTH_UNIX;
2028                         break;
2029                 case 1:
2030                         break;
2031                 default:
2032                         goto out_inval_auth;
2033                 }
2034
2035                 if (args->client_address == NULL)
2036                         goto out_no_client_address;
2037
2038                 status = nfs_parse_devname(dev_name,
2039                                            &args->nfs_server.hostname,
2040                                            NFS4_MAXNAMLEN,
2041                                            &args->nfs_server.export_path,
2042                                            NFS4_MAXPATHLEN);
2043                 if (status < 0)
2044                         return status;
2045
2046                 break;
2047                 }
2048         }
2049
2050         return 0;
2051
2052 out_no_data:
2053         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2054         return -EINVAL;
2055
2056 out_inval_auth:
2057         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2058                  data->auth_flavourlen);
2059         return -EINVAL;
2060
2061 out_no_address:
2062         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2063         return -EINVAL;
2064
2065 out_no_client_address:
2066         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
2067         return -EINVAL;
2068 }
2069
2070 /*
2071  * Get the superblock for an NFS4 mountpoint
2072  */
2073 static int nfs4_get_sb(struct file_system_type *fs_type,
2074         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2075 {
2076         struct nfs_parsed_mount_data *data;
2077         struct super_block *s;
2078         struct nfs_server *server;
2079         struct nfs_fh *mntfh;
2080         struct dentry *mntroot;
2081         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2082         struct nfs_sb_mountdata sb_mntdata = {
2083                 .mntflags = flags,
2084         };
2085         int error = -ENOMEM;
2086
2087         data = kzalloc(sizeof(*data), GFP_KERNEL);
2088         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2089         if (data == NULL || mntfh == NULL)
2090                 goto out_free_fh;
2091
2092         security_init_mnt_opts(&data->lsm_opts);
2093
2094         /* Validate the mount data */
2095         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2096         if (error < 0)
2097                 goto out;
2098
2099         /* Get a volume representation */
2100         server = nfs4_create_server(data, mntfh);
2101         if (IS_ERR(server)) {
2102                 error = PTR_ERR(server);
2103                 goto out;
2104         }
2105         sb_mntdata.server = server;
2106
2107         if (server->flags & NFS4_MOUNT_UNSHARED)
2108                 compare_super = NULL;
2109
2110         /* Get a superblock - note that we may end up sharing one that already exists */
2111         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2112         if (IS_ERR(s)) {
2113                 error = PTR_ERR(s);
2114                 goto out_free;
2115         }
2116
2117         if (s->s_fs_info != server) {
2118                 nfs_free_server(server);
2119                 server = NULL;
2120         } else {
2121                 error = nfs_bdi_register(server);
2122                 if (error)
2123                         goto error_splat_super;
2124         }
2125
2126         if (!s->s_root) {
2127                 /* initial superblock/root creation */
2128                 nfs4_fill_super(s);
2129         }
2130
2131         mntroot = nfs4_get_root(s, mntfh);
2132         if (IS_ERR(mntroot)) {
2133                 error = PTR_ERR(mntroot);
2134                 goto error_splat_super;
2135         }
2136
2137         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2138         if (error)
2139                 goto error_splat_root;
2140
2141         s->s_flags |= MS_ACTIVE;
2142         mnt->mnt_sb = s;
2143         mnt->mnt_root = mntroot;
2144         error = 0;
2145
2146 out:
2147         kfree(data->client_address);
2148         kfree(data->nfs_server.export_path);
2149         kfree(data->nfs_server.hostname);
2150         security_free_mnt_opts(&data->lsm_opts);
2151 out_free_fh:
2152         kfree(mntfh);
2153         kfree(data);
2154         return error;
2155
2156 out_free:
2157         nfs_free_server(server);
2158         goto out;
2159
2160 error_splat_root:
2161         dput(mntroot);
2162 error_splat_super:
2163         up_write(&s->s_umount);
2164         deactivate_super(s);
2165         goto out;
2166 }
2167
2168 static void nfs4_kill_super(struct super_block *sb)
2169 {
2170         struct nfs_server *server = NFS_SB(sb);
2171
2172         nfs_return_all_delegations(sb);
2173         kill_anon_super(sb);
2174
2175         nfs4_renewd_prepare_shutdown(server);
2176         nfs_free_server(server);
2177 }
2178
2179 /*
2180  * Clone an NFS4 server record on xdev traversal (FSID-change)
2181  */
2182 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2183                             const char *dev_name, void *raw_data,
2184                             struct vfsmount *mnt)
2185 {
2186         struct nfs_clone_mount *data = raw_data;
2187         struct super_block *s;
2188         struct nfs_server *server;
2189         struct dentry *mntroot;
2190         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2191         struct nfs_sb_mountdata sb_mntdata = {
2192                 .mntflags = flags,
2193         };
2194         int error;
2195
2196         dprintk("--> nfs4_xdev_get_sb()\n");
2197
2198         /* create a new volume representation */
2199         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2200         if (IS_ERR(server)) {
2201                 error = PTR_ERR(server);
2202                 goto out_err_noserver;
2203         }
2204         sb_mntdata.server = server;
2205
2206         if (server->flags & NFS4_MOUNT_UNSHARED)
2207                 compare_super = NULL;
2208
2209         /* Get a superblock - note that we may end up sharing one that already exists */
2210         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2211         if (IS_ERR(s)) {
2212                 error = PTR_ERR(s);
2213                 goto out_err_nosb;
2214         }
2215
2216         if (s->s_fs_info != server) {
2217                 nfs_free_server(server);
2218                 server = NULL;
2219         } else {
2220                 error = nfs_bdi_register(server);
2221                 if (error)
2222                         goto error_splat_super;
2223         }
2224
2225         if (!s->s_root) {
2226                 /* initial superblock/root creation */
2227                 nfs4_clone_super(s, data->sb);
2228         }
2229
2230         mntroot = nfs4_get_root(s, data->fh);
2231         if (IS_ERR(mntroot)) {
2232                 error = PTR_ERR(mntroot);
2233                 goto error_splat_super;
2234         }
2235         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2236                 dput(mntroot);
2237                 error = -ESTALE;
2238                 goto error_splat_super;
2239         }
2240
2241         s->s_flags |= MS_ACTIVE;
2242         mnt->mnt_sb = s;
2243         mnt->mnt_root = mntroot;
2244
2245         security_sb_clone_mnt_opts(data->sb, s);
2246
2247         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2248         return 0;
2249
2250 out_err_nosb:
2251         nfs_free_server(server);
2252 out_err_noserver:
2253         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2254         return error;
2255
2256 error_splat_super:
2257         up_write(&s->s_umount);
2258         deactivate_super(s);
2259         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2260         return error;
2261 }
2262
2263 /*
2264  * Create an NFS4 server record on referral traversal
2265  */
2266 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2267                                 const char *dev_name, void *raw_data,
2268                                 struct vfsmount *mnt)
2269 {
2270         struct nfs_clone_mount *data = raw_data;
2271         struct super_block *s;
2272         struct nfs_server *server;
2273         struct dentry *mntroot;
2274         struct nfs_fh mntfh;
2275         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2276         struct nfs_sb_mountdata sb_mntdata = {
2277                 .mntflags = flags,
2278         };
2279         int error;
2280
2281         dprintk("--> nfs4_referral_get_sb()\n");
2282
2283         /* create a new volume representation */
2284         server = nfs4_create_referral_server(data, &mntfh);
2285         if (IS_ERR(server)) {
2286                 error = PTR_ERR(server);
2287                 goto out_err_noserver;
2288         }
2289         sb_mntdata.server = server;
2290
2291         if (server->flags & NFS4_MOUNT_UNSHARED)
2292                 compare_super = NULL;
2293
2294         /* Get a superblock - note that we may end up sharing one that already exists */
2295         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2296         if (IS_ERR(s)) {
2297                 error = PTR_ERR(s);
2298                 goto out_err_nosb;
2299         }
2300
2301         if (s->s_fs_info != server) {
2302                 nfs_free_server(server);
2303                 server = NULL;
2304         } else {
2305                 error = nfs_bdi_register(server);
2306                 if (error)
2307                         goto error_splat_super;
2308         }
2309
2310         if (!s->s_root) {
2311                 /* initial superblock/root creation */
2312                 nfs4_fill_super(s);
2313         }
2314
2315         mntroot = nfs4_get_root(s, &mntfh);
2316         if (IS_ERR(mntroot)) {
2317                 error = PTR_ERR(mntroot);
2318                 goto error_splat_super;
2319         }
2320         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2321                 dput(mntroot);
2322                 error = -ESTALE;
2323                 goto error_splat_super;
2324         }
2325
2326         s->s_flags |= MS_ACTIVE;
2327         mnt->mnt_sb = s;
2328         mnt->mnt_root = mntroot;
2329
2330         security_sb_clone_mnt_opts(data->sb, s);
2331
2332         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2333         return 0;
2334
2335 out_err_nosb:
2336         nfs_free_server(server);
2337 out_err_noserver:
2338         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2339         return error;
2340
2341 error_splat_super:
2342         up_write(&s->s_umount);
2343         deactivate_super(s);
2344         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2345         return error;
2346 }
2347
2348 #endif /* CONFIG_NFS_V4 */