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/netdevice.h>
  51 #include <linux/nfs_xdr.h>
  52 #include <linux/magic.h>
  53 #include <linux/parser.h>
  54
  55 #include <asm/system.h>
  56 #include <asm/uaccess.h>
  57
  58 #include "nfs4_fs.h"
  59 #include "callback.h"
  60 #include "delegation.h"
  61 #include "iostat.h"
  62 #include "internal.h"
  63
  64 #define NFSDBG_FACILITY         NFSDBG_VFS
  65
  66 enum {
  67         /* Mount options that take no arguments */
  68         Opt_soft, Opt_hard,
  69         Opt_posix, Opt_noposix,
  70         Opt_cto, Opt_nocto,
  71         Opt_ac, Opt_noac,
  72         Opt_lock, Opt_nolock,
  73         Opt_v2, Opt_v3,
  74         Opt_udp, Opt_tcp, Opt_rdma,
  75         Opt_acl, Opt_noacl,
  76         Opt_rdirplus, Opt_nordirplus,
  77         Opt_sharecache, Opt_nosharecache,
  78
  79         /* Mount options that take integer arguments */
  80         Opt_port,
  81         Opt_rsize, Opt_wsize, Opt_bsize,
  82         Opt_timeo, Opt_retrans,
  83         Opt_acregmin, Opt_acregmax,
  84         Opt_acdirmin, Opt_acdirmax,
  85         Opt_actimeo,
  86         Opt_namelen,
  87         Opt_mountport,
  88         Opt_mountvers,
  89         Opt_nfsvers,
  90
  91         /* Mount options that take string arguments */
  92         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
  93         Opt_addr, Opt_mountaddr, Opt_clientaddr,
  94
  95         /* Mount options that are ignored */
  96         Opt_userspace, Opt_deprecated,
  97
  98         Opt_err
  99 };
 100
 101 static match_table_t nfs_mount_option_tokens = {
 102         { Opt_userspace, "bg" },
 103         { Opt_userspace, "fg" },
 104         { Opt_userspace, "retry=%s" },
 105
 106         { Opt_soft, "soft" },
 107         { Opt_hard, "hard" },
 108         { Opt_deprecated, "intr" },
 109         { Opt_deprecated, "nointr" },
 110         { Opt_posix, "posix" },
 111         { Opt_noposix, "noposix" },
 112         { Opt_cto, "cto" },
 113         { Opt_nocto, "nocto" },
 114         { Opt_ac, "ac" },
 115         { Opt_noac, "noac" },
 116         { Opt_lock, "lock" },
 117         { Opt_nolock, "nolock" },
 118         { Opt_v2, "v2" },
 119         { Opt_v3, "v3" },
 120         { Opt_udp, "udp" },
 121         { Opt_tcp, "tcp" },
 122         { Opt_rdma, "rdma" },
 123         { Opt_acl, "acl" },
 124         { Opt_noacl, "noacl" },
 125         { Opt_rdirplus, "rdirplus" },
 126         { Opt_nordirplus, "nordirplus" },
 127         { Opt_sharecache, "sharecache" },
 128         { Opt_nosharecache, "nosharecache" },
 129
 130         { Opt_port, "port=%u" },
 131         { Opt_rsize, "rsize=%u" },
 132         { Opt_wsize, "wsize=%u" },
 133         { Opt_bsize, "bsize=%u" },
 134         { Opt_timeo, "timeo=%u" },
 135         { Opt_retrans, "retrans=%u" },
 136         { Opt_acregmin, "acregmin=%u" },
 137         { Opt_acregmax, "acregmax=%u" },
 138         { Opt_acdirmin, "acdirmin=%u" },
 139         { Opt_acdirmax, "acdirmax=%u" },
 140         { Opt_actimeo, "actimeo=%u" },
 141         { Opt_namelen, "namlen=%u" },
 142         { Opt_mountport, "mountport=%u" },
 143         { Opt_mountvers, "mountvers=%u" },
 144         { Opt_nfsvers, "nfsvers=%u" },
 145         { Opt_nfsvers, "vers=%u" },
 146
 147         { Opt_sec, "sec=%s" },
 148         { Opt_proto, "proto=%s" },
 149         { Opt_mountproto, "mountproto=%s" },
 150         { Opt_addr, "addr=%s" },
 151         { Opt_clientaddr, "clientaddr=%s" },
 152         { Opt_mounthost, "mounthost=%s" },
 153         { Opt_mountaddr, "mountaddr=%s" },
 154
 155         { Opt_err, NULL }
 156 };
 157
 158 enum {
 159         Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
 160
 161         Opt_xprt_err
 162 };
 163
 164 static match_table_t nfs_xprt_protocol_tokens = {
 165         { Opt_xprt_udp, "udp" },
 166         { Opt_xprt_tcp, "tcp" },
 167         { Opt_xprt_rdma, "rdma" },
 168
 169         { Opt_xprt_err, NULL }
 170 };
 171
 172 enum {
 173         Opt_sec_none, Opt_sec_sys,
 174         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 175         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 176         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 177
 178         Opt_sec_err
 179 };
 180
 181 static match_table_t nfs_secflavor_tokens = {
 182         { Opt_sec_none, "none" },
 183         { Opt_sec_none, "null" },
 184         { Opt_sec_sys, "sys" },
 185
 186         { Opt_sec_krb5, "krb5" },
 187         { Opt_sec_krb5i, "krb5i" },
 188         { Opt_sec_krb5p, "krb5p" },
 189
 190         { Opt_sec_lkey, "lkey" },
 191         { Opt_sec_lkeyi, "lkeyi" },
 192         { Opt_sec_lkeyp, "lkeyp" },
 193
 194         { Opt_sec_spkm, "spkm3" },
 195         { Opt_sec_spkmi, "spkm3i" },
 196         { Opt_sec_spkmp, "spkm3p" },
 197
 198         { Opt_sec_err, NULL }
 199 };
 200
 201
 202 static void nfs_umount_begin(struct super_block *);
 203 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 204 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 205 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 206 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 207 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 208                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 209 static void nfs_kill_super(struct super_block *);
 210 static void nfs_put_super(struct super_block *);
 211 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 212
 213 static struct file_system_type nfs_fs_type = {
 214         .owner          = THIS_MODULE,
 215         .name           = "nfs",
 216         .get_sb         = nfs_get_sb,
 217         .kill_sb        = nfs_kill_super,
 218         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 219 };
 220
 221 struct file_system_type nfs_xdev_fs_type = {
 222         .owner          = THIS_MODULE,
 223         .name           = "nfs",
 224         .get_sb         = nfs_xdev_get_sb,
 225         .kill_sb        = nfs_kill_super,
 226         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 227 };
 228
 229 static const struct super_operations nfs_sops = {
 230         .alloc_inode    = nfs_alloc_inode,
 231         .destroy_inode  = nfs_destroy_inode,
 232         .write_inode    = nfs_write_inode,
 233         .put_super      = nfs_put_super,
 234         .statfs         = nfs_statfs,
 235         .clear_inode    = nfs_clear_inode,
 236         .umount_begin   = nfs_umount_begin,
 237         .show_options   = nfs_show_options,
 238         .show_stats     = nfs_show_stats,
 239         .remount_fs     = nfs_remount,
 240 };
 241
 242 #ifdef CONFIG_NFS_V4
 243 static int nfs4_get_sb(struct file_system_type *fs_type,
 244         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 245 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 246         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 247 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 248         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 249 static void nfs4_kill_super(struct super_block *sb);
 250
 251 static struct file_system_type nfs4_fs_type = {
 252         .owner          = THIS_MODULE,
 253         .name           = "nfs4",
 254         .get_sb         = nfs4_get_sb,
 255         .kill_sb        = nfs4_kill_super,
 256         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 257 };
 258
 259 struct file_system_type nfs4_xdev_fs_type = {
 260         .owner          = THIS_MODULE,
 261         .name           = "nfs4",
 262         .get_sb         = nfs4_xdev_get_sb,
 263         .kill_sb        = nfs4_kill_super,
 264         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 265 };
 266
 267 struct file_system_type nfs4_referral_fs_type = {
 268         .owner          = THIS_MODULE,
 269         .name           = "nfs4",
 270         .get_sb         = nfs4_referral_get_sb,
 271         .kill_sb        = nfs4_kill_super,
 272         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 273 };
 274
 275 static const struct super_operations nfs4_sops = {
 276         .alloc_inode    = nfs_alloc_inode,
 277         .destroy_inode  = nfs_destroy_inode,
 278         .write_inode    = nfs_write_inode,
 279         .statfs         = nfs_statfs,
 280         .clear_inode    = nfs4_clear_inode,
 281         .umount_begin   = nfs_umount_begin,
 282         .show_options   = nfs_show_options,
 283         .show_stats     = nfs_show_stats,
 284         .remount_fs     = nfs_remount,
 285 };
 286 #endif
 287
 288 static struct shrinker acl_shrinker = {
 289         .shrink         = nfs_access_cache_shrinker,
 290         .seeks          = DEFAULT_SEEKS,
 291 };
 292
 293 /*
 294  * Register the NFS filesystems
 295  */
 296 int __init register_nfs_fs(void)
 297 {
 298         int ret;
 299
 300         ret = register_filesystem(&nfs_fs_type);
 301         if (ret < 0)
 302                 goto error_0;
 303
 304         ret = nfs_register_sysctl();
 305         if (ret < 0)
 306                 goto error_1;
 307 #ifdef CONFIG_NFS_V4
 308         ret = register_filesystem(&nfs4_fs_type);
 309         if (ret < 0)
 310                 goto error_2;
 311 #endif
 312         register_shrinker(&acl_shrinker);
 313         return 0;
 314
 315 #ifdef CONFIG_NFS_V4
 316 error_2:
 317         nfs_unregister_sysctl();
 318 #endif
 319 error_1:
 320         unregister_filesystem(&nfs_fs_type);
 321 error_0:
 322         return ret;
 323 }
 324
 325 /*
 326  * Unregister the NFS filesystems
 327  */
 328 void __exit unregister_nfs_fs(void)
 329 {
 330         unregister_shrinker(&acl_shrinker);
 331 #ifdef CONFIG_NFS_V4
 332         unregister_filesystem(&nfs4_fs_type);
 333 #endif
 334         nfs_unregister_sysctl();
 335         unregister_filesystem(&nfs_fs_type);
 336 }
 337
 338 void nfs_sb_active(struct nfs_server *server)
 339 {
 340         atomic_inc(&server->active);
 341 }
 342
 343 void nfs_sb_deactive(struct nfs_server *server)
 344 {
 345         if (atomic_dec_and_test(&server->active))
 346                 wake_up(&server->active_wq);
 347 }
 348
 349 static void nfs_put_super(struct super_block *sb)
 350 {
 351         struct nfs_server *server = NFS_SB(sb);
 352         /*
 353          * Make sure there are no outstanding ops to this server.
 354          * If so, wait for them to finish before allowing the
 355          * unmount to continue.
 356          */
 357         wait_event(server->active_wq, atomic_read(&server->active) == 0);
 358 }
 359
 360 /*
 361  * Deliver file system statistics to userspace
 362  */
 363 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 364 {
 365         struct nfs_server *server = NFS_SB(dentry->d_sb);
 366         unsigned char blockbits;
 367         unsigned long blockres;
 368         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 369         struct nfs_fattr fattr;
 370         struct nfs_fsstat res = {
 371                         .fattr = &fattr,
 372         };
 373         int error;
 374
 375         lock_kernel();
 376
 377         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 378         if (error < 0)
 379                 goto out_err;
 380         buf->f_type = NFS_SUPER_MAGIC;
 381
 382         /*
 383          * Current versions of glibc do not correctly handle the
 384          * case where f_frsize != f_bsize.  Eventually we want to
 385          * report the value of wtmult in this field.
 386          */
 387         buf->f_frsize = dentry->d_sb->s_blocksize;
 388
 389         /*
 390          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 391          * are reported in units of f_frsize.  Linux hasn't had
 392          * an f_frsize field in its statfs struct until recently,
 393          * thus historically Linux's sys_statfs reports these
 394          * fields in units of f_bsize.
 395          */
 396         buf->f_bsize = dentry->d_sb->s_blocksize;
 397         blockbits = dentry->d_sb->s_blocksize_bits;
 398         blockres = (1 << blockbits) - 1;
 399         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 400         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 401         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 402
 403         buf->f_files = res.tfiles;
 404         buf->f_ffree = res.afiles;
 405
 406         buf->f_namelen = server->namelen;
 407
 408         unlock_kernel();
 409         return 0;
 410
 411  out_err:
 412         dprintk("%s: statfs error = %d\n", __func__, -error);
 413         unlock_kernel();
 414         return error;
 415 }
 416
 417 /*
 418  * Map the security flavour number to a name
 419  */
 420 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 421 {
 422         static const struct {
 423                 rpc_authflavor_t flavour;
 424                 const char *str;
 425         } sec_flavours[] = {
 426                 { RPC_AUTH_NULL, "null" },
 427                 { RPC_AUTH_UNIX, "sys" },
 428                 { RPC_AUTH_GSS_KRB5, "krb5" },
 429                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 430                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 431                 { RPC_AUTH_GSS_LKEY, "lkey" },
 432                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 433                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 434                 { RPC_AUTH_GSS_SPKM, "spkm" },
 435                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 436                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 437                 { UINT_MAX, "unknown" }
 438         };
 439         int i;
 440
 441         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 442                 if (sec_flavours[i].flavour == flavour)
 443                         break;
 444         }
 445         return sec_flavours[i].str;
 446 }
 447
 448 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 449                                     int showdefaults)
 450 {
 451         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 452
 453         switch (sap->sa_family) {
 454         case AF_INET: {
 455                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 456                 seq_printf(m, ",mountaddr=" NIPQUAD_FMT,
 457                                 NIPQUAD(sin->sin_addr.s_addr));
 458                 break;
 459         }
 460         case AF_INET6: {
 461                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 462                 seq_printf(m, ",mountaddr=" NIP6_FMT,
 463                                 NIP6(sin6->sin6_addr));
 464                 break;
 465         }
 466         default:
 467                 if (showdefaults)
 468                         seq_printf(m, ",mountaddr=unspecified");
 469         }
 470
 471         if (nfss->mountd_version || showdefaults)
 472                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 473         if (nfss->mountd_port || showdefaults)
 474                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 475
 476         switch (nfss->mountd_protocol) {
 477         case IPPROTO_UDP:
 478                 seq_printf(m, ",mountproto=udp");
 479                 break;
 480         case IPPROTO_TCP:
 481                 seq_printf(m, ",mountproto=tcp");
 482                 break;
 483         default:
 484                 if (showdefaults)
 485                         seq_printf(m, ",mountproto=auto");
 486         }
 487 }
 488
 489 /*
 490  * Describe the mount options in force on this server representation
 491  */
 492 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 493                                    int showdefaults)
 494 {
 495         static const struct proc_nfs_info {
 496                 int flag;
 497                 const char *str;
 498                 const char *nostr;
 499         } nfs_info[] = {
 500                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 501                 { NFS_MOUNT_INTR, ",intr", ",nointr" },
 502                 { NFS_MOUNT_POSIX, ",posix", "" },
 503                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 504                 { NFS_MOUNT_NOAC, ",noac", "" },
 505                 { NFS_MOUNT_NONLM, ",nolock", "" },
 506                 { NFS_MOUNT_NOACL, ",noacl", "" },
 507                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 508                 { NFS_MOUNT_UNSHARED, ",nosharecache", ""},
 509                 { 0, NULL, NULL }
 510         };
 511         const struct proc_nfs_info *nfs_infop;
 512         struct nfs_client *clp = nfss->nfs_client;
 513         u32 version = clp->rpc_ops->version;
 514
 515         seq_printf(m, ",vers=%u", version);
 516         seq_printf(m, ",rsize=%u", nfss->rsize);
 517         seq_printf(m, ",wsize=%u", nfss->wsize);
 518         if (nfss->bsize != 0)
 519                 seq_printf(m, ",bsize=%u", nfss->bsize);
 520         seq_printf(m, ",namlen=%u", nfss->namelen);
 521         if (nfss->acregmin != 3*HZ || showdefaults)
 522                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 523         if (nfss->acregmax != 60*HZ || showdefaults)
 524                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 525         if (nfss->acdirmin != 30*HZ || showdefaults)
 526                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 527         if (nfss->acdirmax != 60*HZ || showdefaults)
 528                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 529         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 530                 if (nfss->flags & nfs_infop->flag)
 531                         seq_puts(m, nfs_infop->str);
 532                 else
 533                         seq_puts(m, nfs_infop->nostr);
 534         }
 535         seq_printf(m, ",proto=%s",
 536                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 537         if (version == 4) {
 538                 if (nfss->port != NFS_PORT)
 539                         seq_printf(m, ",port=%u", nfss->port);
 540         } else
 541                 if (nfss->port)
 542                         seq_printf(m, ",port=%u", nfss->port);
 543
 544         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 545         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 546         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 547
 548         if (version != 4)
 549                 nfs_show_mountd_options(m, nfss, showdefaults);
 550
 551 #ifdef CONFIG_NFS_V4
 552         if (clp->rpc_ops->version == 4)
 553                 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 554 #endif
 555 }
 556
 557 /*
 558  * Describe the mount options on this VFS mountpoint
 559  */
 560 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 561 {
 562         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 563
 564         nfs_show_mount_options(m, nfss, 0);
 565
 566         seq_printf(m, ",addr=%s",
 567                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 568                                                         RPC_DISPLAY_ADDR));
 569
 570         return 0;
 571 }
 572
 573 /*
 574  * Present statistical information for this VFS mountpoint
 575  */
 576 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 577 {
 578         int i, cpu;
 579         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 580         struct rpc_auth *auth = nfss->client->cl_auth;
 581         struct nfs_iostats totals = { };
 582
 583         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 584
 585         /*
 586          * Display all mount option settings
 587          */
 588         seq_printf(m, "\n\topts:\t");
 589         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 590         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 591         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 592         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 593         nfs_show_mount_options(m, nfss, 1);
 594
 595         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 596
 597         seq_printf(m, "\n\tcaps:\t");
 598         seq_printf(m, "caps=0x%x", nfss->caps);
 599         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 600         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 601         seq_printf(m, ",bsize=%u", nfss->bsize);
 602         seq_printf(m, ",namlen=%u", nfss->namelen);
 603
 604 #ifdef CONFIG_NFS_V4
 605         if (nfss->nfs_client->rpc_ops->version == 4) {
 606                 seq_printf(m, "\n\tnfsv4:\t");
 607                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 608                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 609                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 610         }
 611 #endif
 612
 613         /*
 614          * Display security flavor in effect for this mount
 615          */
 616         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 617         if (auth->au_flavor)
 618                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 619
 620         /*
 621          * Display superblock I/O counters
 622          */
 623         for_each_possible_cpu(cpu) {
 624                 struct nfs_iostats *stats;
 625
 626                 preempt_disable();
 627                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 628
 629                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 630                         totals.events[i] += stats->events[i];
 631                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 632                         totals.bytes[i] += stats->bytes[i];
 633
 634                 preempt_enable();
 635         }
 636
 637         seq_printf(m, "\n\tevents:\t");
 638         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 639                 seq_printf(m, "%lu ", totals.events[i]);
 640         seq_printf(m, "\n\tbytes:\t");
 641         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 642                 seq_printf(m, "%Lu ", totals.bytes[i]);
 643         seq_printf(m, "\n");
 644
 645         rpc_print_iostats(m, nfss->client);
 646
 647         return 0;
 648 }
 649
 650 /*
 651  * Begin unmount by attempting to remove all automounted mountpoints we added
 652  * in response to xdev traversals and referrals
 653  */
 654 static void nfs_umount_begin(struct super_block *sb)
 655 {
 656         struct nfs_server *server = NFS_SB(sb);
 657         struct rpc_clnt *rpc;
 658
 659         /* -EIO all pending I/O */
 660         rpc = server->client_acl;
 661         if (!IS_ERR(rpc))
 662                 rpc_killall_tasks(rpc);
 663         rpc = server->client;
 664         if (!IS_ERR(rpc))
 665                 rpc_killall_tasks(rpc);
 666 }
 667
 668 /*
 669  * Set the port number in an address.  Be agnostic about the address family.
 670  */
 671 static void nfs_set_port(struct sockaddr *sap, unsigned short port)
 672 {
 673         switch (sap->sa_family) {
 674         case AF_INET: {
 675                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 676                 ap->sin_port = htons(port);
 677                 break;
 678         }
 679         case AF_INET6: {
 680                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 681                 ap->sin6_port = htons(port);
 682                 break;
 683         }
 684         }
 685 }
 686
 687 /*
 688  * Sanity-check a server address provided by the mount command.
 689  *
 690  * Address family must be initialized, and address must not be
 691  * the ANY address for that family.
 692  */
 693 static int nfs_verify_server_address(struct sockaddr *addr)
 694 {
 695         switch (addr->sa_family) {
 696         case AF_INET: {
 697                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 698                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 699         }
 700         case AF_INET6: {
 701                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 702                 return !ipv6_addr_any(sa);
 703         }
 704         }
 705
 706         return 0;
 707 }
 708
 709 static void nfs_parse_ipv4_address(char *string, size_t str_len,
 710                                    struct sockaddr *sap, size_t *addr_len)
 711 {
 712         struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 713         u8 *addr = (u8 *)&sin->sin_addr.s_addr;
 714
 715         if (str_len <= INET_ADDRSTRLEN) {
 716                 dfprintk(MOUNT, "NFS: parsing IPv4 address %*s\n",
 717                                 (int)str_len, string);
 718
 719                 sin->sin_family = AF_INET;
 720                 *addr_len = sizeof(*sin);
 721                 if (in4_pton(string, str_len, addr, '\0', NULL))
 722                         return;
 723         }
 724
 725         sap->sa_family = AF_UNSPEC;
 726         *addr_len = 0;
 727 }
 728
 729 #define IPV6_SCOPE_DELIMITER    '%'
 730
 731 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 732 static void nfs_parse_ipv6_scope_id(const char *string, const size_t str_len,
 733                                     const char *delim,
 734                                     struct sockaddr_in6 *sin6)
 735 {
 736         char *p;
 737         size_t len;
 738
 739         if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
 740                 return ;
 741         if (*delim != IPV6_SCOPE_DELIMITER)
 742                 return;
 743
 744         len = (string + str_len) - delim - 1;
 745         p = kstrndup(delim + 1, len, GFP_KERNEL);
 746         if (p) {
 747                 unsigned long scope_id = 0;
 748                 struct net_device *dev;
 749
 750                 dev = dev_get_by_name(&init_net, p);
 751                 if (dev != NULL) {
 752                         scope_id = dev->ifindex;
 753                         dev_put(dev);
 754                 } else {
 755                         /* scope_id is set to zero on error */
 756                         strict_strtoul(p, 10, &scope_id);
 757                 }
 758
 759                 kfree(p);
 760                 sin6->sin6_scope_id = scope_id;
 761                 dfprintk(MOUNT, "NFS: IPv6 scope ID = %lu\n", scope_id);
 762         }
 763 }
 764
 765 static void nfs_parse_ipv6_address(char *string, size_t str_len,
 766                                    struct sockaddr *sap, size_t *addr_len)
 767 {
 768         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 769         u8 *addr = (u8 *)&sin6->sin6_addr.in6_u;
 770         const char *delim;
 771
 772         if (str_len <= INET6_ADDRSTRLEN) {
 773                 dfprintk(MOUNT, "NFS: parsing IPv6 address %*s\n",
 774                                 (int)str_len, string);
 775
 776                 sin6->sin6_family = AF_INET6;
 777                 *addr_len = sizeof(*sin6);
 778                 if (in6_pton(string, str_len, addr, IPV6_SCOPE_DELIMITER, &delim)) {
 779                         nfs_parse_ipv6_scope_id(string, str_len, delim, sin6);
 780                         return;
 781                 }
 782         }
 783
 784         sap->sa_family = AF_UNSPEC;
 785         *addr_len = 0;
 786 }
 787 #else
 788 static void nfs_parse_ipv6_address(char *string, size_t str_len,
 789                                    struct sockaddr *sap, size_t *addr_len)
 790 {
 791         sap->sa_family = AF_UNSPEC;
 792         *addr_len = 0;
 793 }
 794 #endif
 795
 796 /*
 797  * Construct a sockaddr based on the contents of a string that contains
 798  * an IP address in presentation format.
 799  *
 800  * If there is a problem constructing the new sockaddr, set the address
 801  * family to AF_UNSPEC.
 802  */
 803 static void nfs_parse_ip_address(char *string, size_t str_len,
 804                                  struct sockaddr *sap, size_t *addr_len)
 805 {
 806         unsigned int i, colons;
 807
 808         colons = 0;
 809         for (i = 0; i < str_len; i++)
 810                 if (string[i] == ':')
 811                         colons++;
 812
 813         if (colons >= 2)
 814                 nfs_parse_ipv6_address(string, str_len, sap, addr_len);
 815         else
 816                 nfs_parse_ipv4_address(string, str_len, sap, addr_len);
 817 }
 818
 819 /*
 820  * Error-check and convert a string of mount options from user space into
 821  * a data structure
 822  */
 823 static int nfs_parse_mount_options(char *raw,
 824                                    struct nfs_parsed_mount_data *mnt)
 825 {
 826         char *p, *string, *secdata;
 827         int rc;
 828
 829         if (!raw) {
 830                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 831                 return 1;
 832         }
 833         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 834
 835         secdata = alloc_secdata();
 836         if (!secdata)
 837                 goto out_nomem;
 838
 839         rc = security_sb_copy_data(raw, secdata);
 840         if (rc)
 841                 goto out_security_failure;
 842
 843         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
 844         if (rc)
 845                 goto out_security_failure;
 846
 847         free_secdata(secdata);
 848
 849         while ((p = strsep(&raw, ",")) != NULL) {
 850                 substring_t args[MAX_OPT_ARGS];
 851                 int option, token;
 852
 853                 if (!*p)
 854                         continue;
 855
 856                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 857
 858                 token = match_token(p, nfs_mount_option_tokens, args);
 859                 switch (token) {
 860                 case Opt_soft:
 861                         mnt->flags |= NFS_MOUNT_SOFT;
 862                         break;
 863                 case Opt_hard:
 864                         mnt->flags &= ~NFS_MOUNT_SOFT;
 865                         break;
 866                 case Opt_posix:
 867                         mnt->flags |= NFS_MOUNT_POSIX;
 868                         break;
 869                 case Opt_noposix:
 870                         mnt->flags &= ~NFS_MOUNT_POSIX;
 871                         break;
 872                 case Opt_cto:
 873                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 874                         break;
 875                 case Opt_nocto:
 876                         mnt->flags |= NFS_MOUNT_NOCTO;
 877                         break;
 878                 case Opt_ac:
 879                         mnt->flags &= ~NFS_MOUNT_NOAC;
 880                         break;
 881                 case Opt_noac:
 882                         mnt->flags |= NFS_MOUNT_NOAC;
 883                         break;
 884                 case Opt_lock:
 885                         mnt->flags &= ~NFS_MOUNT_NONLM;
 886                         break;
 887                 case Opt_nolock:
 888                         mnt->flags |= NFS_MOUNT_NONLM;
 889                         break;
 890                 case Opt_v2:
 891                         mnt->flags &= ~NFS_MOUNT_VER3;
 892                         break;
 893                 case Opt_v3:
 894                         mnt->flags |= NFS_MOUNT_VER3;
 895                         break;
 896                 case Opt_udp:
 897                         mnt->flags &= ~NFS_MOUNT_TCP;
 898                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 899                         mnt->timeo = 7;
 900                         mnt->retrans = 5;
 901                         break;
 902                 case Opt_tcp:
 903                         mnt->flags |= NFS_MOUNT_TCP;
 904                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 905                         mnt->timeo = 600;
 906                         mnt->retrans = 2;
 907                         break;
 908                 case Opt_rdma:
 909                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 910                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 911                         mnt->timeo = 600;
 912                         mnt->retrans = 2;
 913                         break;
 914                 case Opt_acl:
 915                         mnt->flags &= ~NFS_MOUNT_NOACL;
 916                         break;
 917                 case Opt_noacl:
 918                         mnt->flags |= NFS_MOUNT_NOACL;
 919                         break;
 920                 case Opt_rdirplus:
 921                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 922                         break;
 923                 case Opt_nordirplus:
 924                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 925                         break;
 926                 case Opt_sharecache:
 927                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 928                         break;
 929                 case Opt_nosharecache:
 930                         mnt->flags |= NFS_MOUNT_UNSHARED;
 931                         break;
 932
 933                 case Opt_port:
 934                         if (match_int(args, &option))
 935                                 return 0;
 936                         if (option < 0 || option > 65535)
 937                                 return 0;
 938                         mnt->nfs_server.port = option;
 939                         break;
 940                 case Opt_rsize:
 941                         if (match_int(args, &mnt->rsize))
 942                                 return 0;
 943                         break;
 944                 case Opt_wsize:
 945                         if (match_int(args, &mnt->wsize))
 946                                 return 0;
 947                         break;
 948                 case Opt_bsize:
 949                         if (match_int(args, &option))
 950                                 return 0;
 951                         if (option < 0)
 952                                 return 0;
 953                         mnt->bsize = option;
 954                         break;
 955                 case Opt_timeo:
 956                         if (match_int(args, &mnt->timeo))
 957                                 return 0;
 958                         break;
 959                 case Opt_retrans:
 960                         if (match_int(args, &mnt->retrans))
 961                                 return 0;
 962                         break;
 963                 case Opt_acregmin:
 964                         if (match_int(args, &mnt->acregmin))
 965                                 return 0;
 966                         break;
 967                 case Opt_acregmax:
 968                         if (match_int(args, &mnt->acregmax))
 969                                 return 0;
 970                         break;
 971                 case Opt_acdirmin:
 972                         if (match_int(args, &mnt->acdirmin))
 973                                 return 0;
 974                         break;
 975                 case Opt_acdirmax:
 976                         if (match_int(args, &mnt->acdirmax))
 977                                 return 0;
 978                         break;
 979                 case Opt_actimeo:
 980                         if (match_int(args, &option))
 981                                 return 0;
 982                         if (option < 0)
 983                                 return 0;
 984                         mnt->acregmin =
 985                         mnt->acregmax =
 986                         mnt->acdirmin =
 987                         mnt->acdirmax = option;
 988                         break;
 989                 case Opt_namelen:
 990                         if (match_int(args, &mnt->namlen))
 991                                 return 0;
 992                         break;
 993                 case Opt_mountport:
 994                         if (match_int(args, &option))
 995                                 return 0;
 996                         if (option < 0 || option > 65535)
 997                                 return 0;
 998                         mnt->mount_server.port = option;
 999                         break;
1000                 case Opt_mountvers:
1001                         if (match_int(args, &option))
1002                                 return 0;
1003                         if (option < 0)
1004                                 return 0;
1005                         mnt->mount_server.version = option;
1006                         break;
1007                 case Opt_nfsvers:
1008                         if (match_int(args, &option))
1009                                 return 0;
1010                         switch (option) {
1011                         case 2:
1012                                 mnt->flags &= ~NFS_MOUNT_VER3;
1013                                 break;
1014                         case 3:
1015                                 mnt->flags |= NFS_MOUNT_VER3;
1016                                 break;
1017                         default:
1018                                 goto out_unrec_vers;
1019                         }
1020                         break;
1021
1022                 case Opt_sec:
1023                         string = match_strdup(args);
1024                         if (string == NULL)
1025                                 goto out_nomem;
1026                         token = match_token(string, nfs_secflavor_tokens, args);
1027                         kfree(string);
1028
1029                         /*
1030                          * The flags setting is for v2/v3.  The flavor_len
1031                          * setting is for v4.  v2/v3 also need to know the
1032                          * difference between NULL and UNIX.
1033                          */
1034                         switch (token) {
1035                         case Opt_sec_none:
1036                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
1037                                 mnt->auth_flavor_len = 0;
1038                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1039                                 break;
1040                         case Opt_sec_sys:
1041                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
1042                                 mnt->auth_flavor_len = 0;
1043                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1044                                 break;
1045                         case Opt_sec_krb5:
1046                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1047                                 mnt->auth_flavor_len = 1;
1048                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1049                                 break;
1050                         case Opt_sec_krb5i:
1051                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1052                                 mnt->auth_flavor_len = 1;
1053                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1054                                 break;
1055                         case Opt_sec_krb5p:
1056                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1057                                 mnt->auth_flavor_len = 1;
1058                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1059                                 break;
1060                         case Opt_sec_lkey:
1061                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1062                                 mnt->auth_flavor_len = 1;
1063                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1064                                 break;
1065                         case Opt_sec_lkeyi:
1066                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1067                                 mnt->auth_flavor_len = 1;
1068                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1069                                 break;
1070                         case Opt_sec_lkeyp:
1071                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1072                                 mnt->auth_flavor_len = 1;
1073                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1074                                 break;
1075                         case Opt_sec_spkm:
1076                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1077                                 mnt->auth_flavor_len = 1;
1078                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1079                                 break;
1080                         case Opt_sec_spkmi:
1081                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1082                                 mnt->auth_flavor_len = 1;
1083                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1084                                 break;
1085                         case Opt_sec_spkmp:
1086                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1087                                 mnt->auth_flavor_len = 1;
1088                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1089                                 break;
1090                         default:
1091                                 goto out_unrec_sec;
1092                         }
1093                         break;
1094                 case Opt_proto:
1095                         string = match_strdup(args);
1096                         if (string == NULL)
1097                                 goto out_nomem;
1098                         token = match_token(string,
1099                                             nfs_xprt_protocol_tokens, args);
1100                         kfree(string);
1101
1102                         switch (token) {
1103                         case Opt_xprt_udp:
1104                                 mnt->flags &= ~NFS_MOUNT_TCP;
1105                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1106                                 mnt->timeo = 7;
1107                                 mnt->retrans = 5;
1108                                 break;
1109                         case Opt_xprt_tcp:
1110                                 mnt->flags |= NFS_MOUNT_TCP;
1111                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1112                                 mnt->timeo = 600;
1113                                 mnt->retrans = 2;
1114                                 break;
1115                         case Opt_xprt_rdma:
1116                                 /* vector side protocols to TCP */
1117                                 mnt->flags |= NFS_MOUNT_TCP;
1118                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1119                                 mnt->timeo = 600;
1120                                 mnt->retrans = 2;
1121                                 break;
1122                         default:
1123                                 goto out_unrec_xprt;
1124                         }
1125                         break;
1126                 case Opt_mountproto:
1127                         string = match_strdup(args);
1128                         if (string == NULL)
1129                                 goto out_nomem;
1130                         token = match_token(string,
1131                                             nfs_xprt_protocol_tokens, args);
1132                         kfree(string);
1133
1134                         switch (token) {
1135                         case Opt_xprt_udp:
1136                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1137                                 break;
1138                         case Opt_xprt_tcp:
1139                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1140                                 break;
1141                         case Opt_xprt_rdma: /* not used for side protocols */
1142                         default:
1143                                 goto out_unrec_xprt;
1144                         }
1145                         break;
1146                 case Opt_addr:
1147                         string = match_strdup(args);
1148                         if (string == NULL)
1149                                 goto out_nomem;
1150                         nfs_parse_ip_address(string, strlen(string),
1151                                              (struct sockaddr *)
1152                                                 &mnt->nfs_server.address,
1153                                              &mnt->nfs_server.addrlen);
1154                         kfree(string);
1155                         break;
1156                 case Opt_clientaddr:
1157                         string = match_strdup(args);
1158                         if (string == NULL)
1159                                 goto out_nomem;
1160                         kfree(mnt->client_address);
1161                         mnt->client_address = string;
1162                         break;
1163                 case Opt_mounthost:
1164                         string = match_strdup(args);
1165                         if (string == NULL)
1166                                 goto out_nomem;
1167                         kfree(mnt->mount_server.hostname);
1168                         mnt->mount_server.hostname = string;
1169                         break;
1170                 case Opt_mountaddr:
1171                         string = match_strdup(args);
1172                         if (string == NULL)
1173                                 goto out_nomem;
1174                         nfs_parse_ip_address(string, strlen(string),
1175                                              (struct sockaddr *)
1176                                                 &mnt->mount_server.address,
1177                                              &mnt->mount_server.addrlen);
1178                         kfree(string);
1179                         break;
1180
1181                 case Opt_userspace:
1182                 case Opt_deprecated:
1183                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1184                                         "'%s'\n", p);
1185                         break;
1186
1187                 default:
1188                         goto out_unknown;
1189                 }
1190         }
1191
1192         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
1193                                 mnt->nfs_server.port);
1194
1195         return 1;
1196
1197 out_nomem:
1198         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1199         return 0;
1200 out_security_failure:
1201         free_secdata(secdata);
1202         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1203         return 0;
1204 out_unrec_vers:
1205         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1206         return 0;
1207
1208 out_unrec_xprt:
1209         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1210         return 0;
1211
1212 out_unrec_sec:
1213         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1214         return 0;
1215
1216 out_unknown:
1217         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1218         return 0;
1219 }
1220
1221 /*
1222  * Use the remote server's MOUNT service to request the NFS file handle
1223  * corresponding to the provided path.
1224  */
1225 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1226                          struct nfs_fh *root_fh)
1227 {
1228         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1229         char *hostname;
1230         int status;
1231
1232         if (args->mount_server.version == 0) {
1233                 if (args->flags & NFS_MOUNT_VER3)
1234                         args->mount_server.version = NFS_MNT3_VERSION;
1235                 else
1236                         args->mount_server.version = NFS_MNT_VERSION;
1237         }
1238
1239         if (args->mount_server.hostname)
1240                 hostname = args->mount_server.hostname;
1241         else
1242                 hostname = args->nfs_server.hostname;
1243
1244         /*
1245          * Construct the mount server's address.
1246          */
1247         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1248                 memcpy(sap, &args->nfs_server.address,
1249                        args->nfs_server.addrlen);
1250                 args->mount_server.addrlen = args->nfs_server.addrlen;
1251         }
1252
1253         /*
1254          * autobind will be used if mount_server.port == 0
1255          */
1256         nfs_set_port(sap, args->mount_server.port);
1257
1258         /*
1259          * Now ask the mount server to map our export path
1260          * to a file handle.
1261          */
1262         status = nfs_mount(sap,
1263                            args->mount_server.addrlen,
1264                            hostname,
1265                            args->nfs_server.export_path,
1266                            args->mount_server.version,
1267                            args->mount_server.protocol,
1268                            root_fh);
1269         if (status == 0)
1270                 return 0;
1271
1272         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1273                         hostname, status);
1274         return status;
1275 }
1276
1277 static int nfs_parse_simple_hostname(const char *dev_name,
1278                                      char **hostname, size_t maxnamlen,
1279                                      char **export_path, size_t maxpathlen)
1280 {
1281         size_t len;
1282         char *colon, *comma;
1283
1284         colon = strchr(dev_name, ':');
1285         if (colon == NULL)
1286                 goto out_bad_devname;
1287
1288         len = colon - dev_name;
1289         if (len > maxnamlen)
1290                 goto out_hostname;
1291
1292         /* N.B. caller will free nfs_server.hostname in all cases */
1293         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1294         if (!*hostname)
1295                 goto out_nomem;
1296
1297         /* kill possible hostname list: not supported */
1298         comma = strchr(*hostname, ',');
1299         if (comma != NULL) {
1300                 if (comma == *hostname)
1301                         goto out_bad_devname;
1302                 *comma = '\0';
1303         }
1304
1305         colon++;
1306         len = strlen(colon);
1307         if (len > maxpathlen)
1308                 goto out_path;
1309         *export_path = kstrndup(colon, len, GFP_KERNEL);
1310         if (!*export_path)
1311                 goto out_nomem;
1312
1313         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1314         return 0;
1315
1316 out_bad_devname:
1317         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1318         return -EINVAL;
1319
1320 out_nomem:
1321         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1322         return -ENOMEM;
1323
1324 out_hostname:
1325         dfprintk(MOUNT, "NFS: server hostname too long\n");
1326         return -ENAMETOOLONG;
1327
1328 out_path:
1329         dfprintk(MOUNT, "NFS: export pathname too long\n");
1330         return -ENAMETOOLONG;
1331 }
1332
1333 /*
1334  * Hostname has square brackets around it because it contains one or
1335  * more colons.  We look for the first closing square bracket, and a
1336  * colon must follow it.
1337  */
1338 static int nfs_parse_protected_hostname(const char *dev_name,
1339                                         char **hostname, size_t maxnamlen,
1340                                         char **export_path, size_t maxpathlen)
1341 {
1342         size_t len;
1343         char *start, *end;
1344
1345         start = (char *)(dev_name + 1);
1346
1347         end = strchr(start, ']');
1348         if (end == NULL)
1349                 goto out_bad_devname;
1350         if (*(end + 1) != ':')
1351                 goto out_bad_devname;
1352
1353         len = end - start;
1354         if (len > maxnamlen)
1355                 goto out_hostname;
1356
1357         /* N.B. caller will free nfs_server.hostname in all cases */
1358         *hostname = kstrndup(start, len, GFP_KERNEL);
1359         if (*hostname == NULL)
1360                 goto out_nomem;
1361
1362         end += 2;
1363         len = strlen(end);
1364         if (len > maxpathlen)
1365                 goto out_path;
1366         *export_path = kstrndup(end, len, GFP_KERNEL);
1367         if (!*export_path)
1368                 goto out_nomem;
1369
1370         return 0;
1371
1372 out_bad_devname:
1373         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1374         return -EINVAL;
1375
1376 out_nomem:
1377         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1378         return -ENOMEM;
1379
1380 out_hostname:
1381         dfprintk(MOUNT, "NFS: server hostname too long\n");
1382         return -ENAMETOOLONG;
1383
1384 out_path:
1385         dfprintk(MOUNT, "NFS: export pathname too long\n");
1386         return -ENAMETOOLONG;
1387 }
1388
1389 /*
1390  * Split "dev_name" into "hostname:export_path".
1391  *
1392  * The leftmost colon demarks the split between the server's hostname
1393  * and the export path.  If the hostname starts with a left square
1394  * bracket, then it may contain colons.
1395  *
1396  * Note: caller frees hostname and export path, even on error.
1397  */
1398 static int nfs_parse_devname(const char *dev_name,
1399                              char **hostname, size_t maxnamlen,
1400                              char **export_path, size_t maxpathlen)
1401 {
1402         if (*dev_name == '[')
1403                 return nfs_parse_protected_hostname(dev_name,
1404                                                     hostname, maxnamlen,
1405                                                     export_path, maxpathlen);
1406
1407         return nfs_parse_simple_hostname(dev_name,
1408                                          hostname, maxnamlen,
1409                                          export_path, maxpathlen);
1410 }
1411
1412 /*
1413  * Validate the NFS2/NFS3 mount data
1414  * - fills in the mount root filehandle
1415  *
1416  * For option strings, user space handles the following behaviors:
1417  *
1418  * + DNS: mapping server host name to IP address ("addr=" option)
1419  *
1420  * + failure mode: how to behave if a mount request can't be handled
1421  *   immediately ("fg/bg" option)
1422  *
1423  * + retry: how often to retry a mount request ("retry=" option)
1424  *
1425  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1426  *   mountproto=tcp after mountproto=udp, and so on
1427  */
1428 static int nfs_validate_mount_data(void *options,
1429                                    struct nfs_parsed_mount_data *args,
1430                                    struct nfs_fh *mntfh,
1431                                    const char *dev_name)
1432 {
1433         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1434
1435         if (data == NULL)
1436                 goto out_no_data;
1437
1438         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1439         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1440         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1441         args->timeo             = 600;
1442         args->retrans           = 2;
1443         args->acregmin          = 3;
1444         args->acregmax          = 60;
1445         args->acdirmin          = 30;
1446         args->acdirmax          = 60;
1447         args->mount_server.port = 0;    /* autobind unless user sets port */
1448         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1449         args->nfs_server.port   = 0;    /* autobind unless user sets port */
1450         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1451
1452         switch (data->version) {
1453         case 1:
1454                 data->namlen = 0;
1455         case 2:
1456                 data->bsize = 0;
1457         case 3:
1458                 if (data->flags & NFS_MOUNT_VER3)
1459                         goto out_no_v3;
1460                 data->root.size = NFS2_FHSIZE;
1461                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1462         case 4:
1463                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1464                         goto out_no_sec;
1465         case 5:
1466                 memset(data->context, 0, sizeof(data->context));
1467         case 6:
1468                 if (data->flags & NFS_MOUNT_VER3) {
1469                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1470                                 goto out_invalid_fh;
1471                         mntfh->size = data->root.size;
1472                 } else
1473                         mntfh->size = NFS2_FHSIZE;
1474
1475
1476                 memcpy(mntfh->data, data->root.data, mntfh->size);
1477                 if (mntfh->size < sizeof(mntfh->data))
1478                         memset(mntfh->data + mntfh->size, 0,
1479                                sizeof(mntfh->data) - mntfh->size);
1480
1481                 /*
1482                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1483                  * can deal with.
1484                  */
1485                 args->flags             = data->flags;
1486                 args->rsize             = data->rsize;
1487                 args->wsize             = data->wsize;
1488                 args->timeo             = data->timeo;
1489                 args->retrans           = data->retrans;
1490                 args->acregmin          = data->acregmin;
1491                 args->acregmax          = data->acregmax;
1492                 args->acdirmin          = data->acdirmin;
1493                 args->acdirmax          = data->acdirmax;
1494
1495                 memcpy(&args->nfs_server.address, &data->addr,
1496                        sizeof(data->addr));
1497                 args->nfs_server.addrlen = sizeof(data->addr);
1498                 if (!nfs_verify_server_address((struct sockaddr *)
1499                                                 &args->nfs_server.address))
1500                         goto out_no_address;
1501
1502                 if (!(data->flags & NFS_MOUNT_TCP))
1503                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1504                 /* N.B. caller will free nfs_server.hostname in all cases */
1505                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1506                 args->namlen            = data->namlen;
1507                 args->bsize             = data->bsize;
1508                 args->auth_flavors[0]   = data->pseudoflavor;
1509                 if (!args->nfs_server.hostname)
1510                         goto out_nomem;
1511
1512                 /*
1513                  * The legacy version 6 binary mount data from userspace has a
1514                  * field used only to transport selinux information into the
1515                  * the kernel.  To continue to support that functionality we
1516                  * have a touch of selinux knowledge here in the NFS code. The
1517                  * userspace code converted context=blah to just blah so we are
1518                  * converting back to the full string selinux understands.
1519                  */
1520                 if (data->context[0]){
1521 #ifdef CONFIG_SECURITY_SELINUX
1522                         int rc;
1523                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1524                         if (!opts_str)
1525                                 return -ENOMEM;
1526                         strcpy(opts_str, "context=");
1527                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1528                         strcat(opts_str, &data->context[0]);
1529                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1530                         kfree(opts_str);
1531                         if (rc)
1532                                 return rc;
1533 #else
1534                         return -EINVAL;
1535 #endif
1536                 }
1537
1538                 break;
1539         default: {
1540                 int status;
1541
1542                 if (nfs_parse_mount_options((char *)options, args) == 0)
1543                         return -EINVAL;
1544
1545                 if (!nfs_verify_server_address((struct sockaddr *)
1546                                                 &args->nfs_server.address))
1547                         goto out_no_address;
1548
1549                 status = nfs_parse_devname(dev_name,
1550                                            &args->nfs_server.hostname,
1551                                            PAGE_SIZE,
1552                                            &args->nfs_server.export_path,
1553                                            NFS_MAXPATHLEN);
1554                 if (!status)
1555                         status = nfs_try_mount(args, mntfh);
1556
1557                 kfree(args->nfs_server.export_path);
1558                 args->nfs_server.export_path = NULL;
1559
1560                 if (status)
1561                         return status;
1562
1563                 break;
1564                 }
1565         }
1566
1567         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1568                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1569
1570 #ifndef CONFIG_NFS_V3
1571         if (args->flags & NFS_MOUNT_VER3)
1572                 goto out_v3_not_compiled;
1573 #endif /* !CONFIG_NFS_V3 */
1574
1575         return 0;
1576
1577 out_no_data:
1578         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1579         return -EINVAL;
1580
1581 out_no_v3:
1582         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1583                  data->version);
1584         return -EINVAL;
1585
1586 out_no_sec:
1587         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1588         return -EINVAL;
1589
1590 #ifndef CONFIG_NFS_V3
1591 out_v3_not_compiled:
1592         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1593         return -EPROTONOSUPPORT;
1594 #endif /* !CONFIG_NFS_V3 */
1595
1596 out_nomem:
1597         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1598         return -ENOMEM;
1599
1600 out_no_address:
1601         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1602         return -EINVAL;
1603
1604 out_invalid_fh:
1605         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1606         return -EINVAL;
1607 }
1608
1609 static int
1610 nfs_compare_remount_data(struct nfs_server *nfss,
1611                          struct nfs_parsed_mount_data *data)
1612 {
1613         if (data->flags != nfss->flags ||
1614             data->rsize != nfss->rsize ||
1615             data->wsize != nfss->wsize ||
1616             data->retrans != nfss->client->cl_timeout->to_retries ||
1617             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
1618             data->acregmin != nfss->acregmin / HZ ||
1619             data->acregmax != nfss->acregmax / HZ ||
1620             data->acdirmin != nfss->acdirmin / HZ ||
1621             data->acdirmax != nfss->acdirmax / HZ ||
1622             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
1623             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
1624             memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1625                    data->nfs_server.addrlen) != 0)
1626                 return -EINVAL;
1627
1628         return 0;
1629 }
1630
1631 static int
1632 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
1633 {
1634         int error;
1635         struct nfs_server *nfss = sb->s_fs_info;
1636         struct nfs_parsed_mount_data *data;
1637         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
1638         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
1639         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
1640
1641         /*
1642          * Userspace mount programs that send binary options generally send
1643          * them populated with default values. We have no way to know which
1644          * ones were explicitly specified. Fall back to legacy behavior and
1645          * just return success.
1646          */
1647         if ((nfsvers == 4 && options4->version == 1) ||
1648             (nfsvers <= 3 && options->version >= 1 &&
1649              options->version <= 6))
1650                 return 0;
1651
1652         data = kzalloc(sizeof(*data), GFP_KERNEL);
1653         if (data == NULL)
1654                 return -ENOMEM;
1655
1656         /* fill out struct with values from existing mount */
1657         data->flags = nfss->flags;
1658         data->rsize = nfss->rsize;
1659         data->wsize = nfss->wsize;
1660         data->retrans = nfss->client->cl_timeout->to_retries;
1661         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
1662         data->acregmin = nfss->acregmin / HZ;
1663         data->acregmax = nfss->acregmax / HZ;
1664         data->acdirmin = nfss->acdirmin / HZ;
1665         data->acdirmax = nfss->acdirmax / HZ;
1666         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
1667         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1668         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
1669                 data->nfs_server.addrlen);
1670
1671         /* overwrite those values with any that were specified */
1672         error = nfs_parse_mount_options((char *)options, data);
1673         if (error < 0)
1674                 goto out;
1675
1676         /* compare new mount options with old ones */
1677         error = nfs_compare_remount_data(nfss, data);
1678 out:
1679         kfree(data);
1680         return error;
1681 }
1682
1683 /*
1684  * Initialise the common bits of the superblock
1685  */
1686 static inline void nfs_initialise_sb(struct super_block *sb)
1687 {
1688         struct nfs_server *server = NFS_SB(sb);
1689
1690         sb->s_magic = NFS_SUPER_MAGIC;
1691
1692         /* We probably want something more informative here */
1693         snprintf(sb->s_id, sizeof(sb->s_id),
1694                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1695
1696         if (sb->s_blocksize == 0)
1697                 sb->s_blocksize = nfs_block_bits(server->wsize,
1698                                                  &sb->s_blocksize_bits);
1699
1700         if (server->flags & NFS_MOUNT_NOAC)
1701                 sb->s_flags |= MS_SYNCHRONOUS;
1702
1703         nfs_super_set_maxbytes(sb, server->maxfilesize);
1704 }
1705
1706 /*
1707  * Finish setting up an NFS2/3 superblock
1708  */
1709 static void nfs_fill_super(struct super_block *sb,
1710                            struct nfs_parsed_mount_data *data)
1711 {
1712         struct nfs_server *server = NFS_SB(sb);
1713
1714         sb->s_blocksize_bits = 0;
1715         sb->s_blocksize = 0;
1716         if (data->bsize)
1717                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1718
1719         if (server->flags & NFS_MOUNT_VER3) {
1720                 /* The VFS shouldn't apply the umask to mode bits. We will do
1721                  * so ourselves when necessary.
1722                  */
1723                 sb->s_flags |= MS_POSIXACL;
1724                 sb->s_time_gran = 1;
1725         }
1726
1727         sb->s_op = &nfs_sops;
1728         nfs_initialise_sb(sb);
1729 }
1730
1731 /*
1732  * Finish setting up a cloned NFS2/3 superblock
1733  */
1734 static void nfs_clone_super(struct super_block *sb,
1735                             const struct super_block *old_sb)
1736 {
1737         struct nfs_server *server = NFS_SB(sb);
1738
1739         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1740         sb->s_blocksize = old_sb->s_blocksize;
1741         sb->s_maxbytes = old_sb->s_maxbytes;
1742
1743         if (server->flags & NFS_MOUNT_VER3) {
1744                 /* The VFS shouldn't apply the umask to mode bits. We will do
1745                  * so ourselves when necessary.
1746                  */
1747                 sb->s_flags |= MS_POSIXACL;
1748                 sb->s_time_gran = 1;
1749         }
1750
1751         sb->s_op = old_sb->s_op;
1752         nfs_initialise_sb(sb);
1753 }
1754
1755 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1756
1757 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1758 {
1759         const struct nfs_server *a = s->s_fs_info;
1760         const struct rpc_clnt *clnt_a = a->client;
1761         const struct rpc_clnt *clnt_b = b->client;
1762
1763         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1764                 goto Ebusy;
1765         if (a->nfs_client != b->nfs_client)
1766                 goto Ebusy;
1767         if (a->flags != b->flags)
1768                 goto Ebusy;
1769         if (a->wsize != b->wsize)
1770                 goto Ebusy;
1771         if (a->rsize != b->rsize)
1772                 goto Ebusy;
1773         if (a->acregmin != b->acregmin)
1774                 goto Ebusy;
1775         if (a->acregmax != b->acregmax)
1776                 goto Ebusy;
1777         if (a->acdirmin != b->acdirmin)
1778                 goto Ebusy;
1779         if (a->acdirmax != b->acdirmax)
1780                 goto Ebusy;
1781         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1782                 goto Ebusy;
1783         return 1;
1784 Ebusy:
1785         return 0;
1786 }
1787
1788 struct nfs_sb_mountdata {
1789         struct nfs_server *server;
1790         int mntflags;
1791 };
1792
1793 static int nfs_set_super(struct super_block *s, void *data)
1794 {
1795         struct nfs_sb_mountdata *sb_mntdata = data;
1796         struct nfs_server *server = sb_mntdata->server;
1797         int ret;
1798
1799         s->s_flags = sb_mntdata->mntflags;
1800         s->s_fs_info = server;
1801         ret = set_anon_super(s, server);
1802         if (ret == 0)
1803                 server->s_dev = s->s_dev;
1804         return ret;
1805 }
1806
1807 static int nfs_compare_super_address(struct nfs_server *server1,
1808                                      struct nfs_server *server2)
1809 {
1810         struct sockaddr *sap1, *sap2;
1811
1812         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1813         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1814
1815         if (sap1->sa_family != sap2->sa_family)
1816                 return 0;
1817
1818         switch (sap1->sa_family) {
1819         case AF_INET: {
1820                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1821                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1822                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1823                         return 0;
1824                 if (sin1->sin_port != sin2->sin_port)
1825                         return 0;
1826                 break;
1827         }
1828         case AF_INET6: {
1829                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1830                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1831                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1832                         return 0;
1833                 if (sin1->sin6_port != sin2->sin6_port)
1834                         return 0;
1835                 break;
1836         }
1837         default:
1838                 return 0;
1839         }
1840
1841         return 1;
1842 }
1843
1844 static int nfs_compare_super(struct super_block *sb, void *data)
1845 {
1846         struct nfs_sb_mountdata *sb_mntdata = data;
1847         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1848         int mntflags = sb_mntdata->mntflags;
1849
1850         if (!nfs_compare_super_address(old, server))
1851                 return 0;
1852         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1853         if (old->flags & NFS_MOUNT_UNSHARED)
1854                 return 0;
1855         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1856                 return 0;
1857         return nfs_compare_mount_options(sb, server, mntflags);
1858 }
1859
1860 static int nfs_bdi_register(struct nfs_server *server)
1861 {
1862         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
1863 }
1864
1865 static int nfs_get_sb(struct file_system_type *fs_type,
1866         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1867 {
1868         struct nfs_server *server = NULL;
1869         struct super_block *s;
1870         struct nfs_parsed_mount_data *data;
1871         struct nfs_fh *mntfh;
1872         struct dentry *mntroot;
1873         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1874         struct nfs_sb_mountdata sb_mntdata = {
1875                 .mntflags = flags,
1876         };
1877         int error = -ENOMEM;
1878
1879         data = kzalloc(sizeof(*data), GFP_KERNEL);
1880         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
1881         if (data == NULL || mntfh == NULL)
1882                 goto out_free_fh;
1883
1884         security_init_mnt_opts(&data->lsm_opts);
1885
1886         /* Validate the mount data */
1887         error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
1888         if (error < 0)
1889                 goto out;
1890
1891         /* Get a volume representation */
1892         server = nfs_create_server(data, mntfh);
1893         if (IS_ERR(server)) {
1894                 error = PTR_ERR(server);
1895                 goto out;
1896         }
1897         sb_mntdata.server = server;
1898
1899         if (server->flags & NFS_MOUNT_UNSHARED)
1900                 compare_super = NULL;
1901
1902         /* Get a superblock - note that we may end up sharing one that already exists */
1903         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1904         if (IS_ERR(s)) {
1905                 error = PTR_ERR(s);
1906                 goto out_err_nosb;
1907         }
1908
1909         if (s->s_fs_info != server) {
1910                 nfs_free_server(server);
1911                 server = NULL;
1912         } else {
1913                 error = nfs_bdi_register(server);
1914                 if (error)
1915                         goto error_splat_super;
1916         }
1917
1918         if (!s->s_root) {
1919                 /* initial superblock/root creation */
1920                 nfs_fill_super(s, data);
1921         }
1922
1923         mntroot = nfs_get_root(s, mntfh);
1924         if (IS_ERR(mntroot)) {
1925                 error = PTR_ERR(mntroot);
1926                 goto error_splat_super;
1927         }
1928
1929         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
1930         if (error)
1931                 goto error_splat_root;
1932
1933         s->s_flags |= MS_ACTIVE;
1934         mnt->mnt_sb = s;
1935         mnt->mnt_root = mntroot;
1936         error = 0;
1937
1938 out:
1939         kfree(data->nfs_server.hostname);
1940         kfree(data->mount_server.hostname);
1941         security_free_mnt_opts(&data->lsm_opts);
1942 out_free_fh:
1943         kfree(mntfh);
1944         kfree(data);
1945         return error;
1946
1947 out_err_nosb:
1948         nfs_free_server(server);
1949         goto out;
1950
1951 error_splat_root:
1952         dput(mntroot);
1953 error_splat_super:
1954         up_write(&s->s_umount);
1955         deactivate_super(s);
1956         goto out;
1957 }
1958
1959 /*
1960  * Destroy an NFS2/3 superblock
1961  */
1962 static void nfs_kill_super(struct super_block *s)
1963 {
1964         struct nfs_server *server = NFS_SB(s);
1965
1966         bdi_unregister(&server->backing_dev_info);
1967         kill_anon_super(s);
1968         nfs_free_server(server);
1969 }
1970
1971 /*
1972  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1973  */
1974 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1975                            const char *dev_name, void *raw_data,
1976                            struct vfsmount *mnt)
1977 {
1978         struct nfs_clone_mount *data = raw_data;
1979         struct super_block *s;
1980         struct nfs_server *server;
1981         struct dentry *mntroot;
1982         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1983         struct nfs_sb_mountdata sb_mntdata = {
1984                 .mntflags = flags,
1985         };
1986         int error;
1987
1988         dprintk("--> nfs_xdev_get_sb()\n");
1989
1990         /* create a new volume representation */
1991         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1992         if (IS_ERR(server)) {
1993                 error = PTR_ERR(server);
1994                 goto out_err_noserver;
1995         }
1996         sb_mntdata.server = server;
1997
1998         if (server->flags & NFS_MOUNT_UNSHARED)
1999                 compare_super = NULL;
2000
2001         /* Get a superblock - note that we may end up sharing one that already exists */
2002         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2003         if (IS_ERR(s)) {
2004                 error = PTR_ERR(s);
2005                 goto out_err_nosb;
2006         }
2007
2008         if (s->s_fs_info != server) {
2009                 nfs_free_server(server);
2010                 server = NULL;
2011         } else {
2012                 error = nfs_bdi_register(server);
2013                 if (error)
2014                         goto error_splat_super;
2015         }
2016
2017         if (!s->s_root) {
2018                 /* initial superblock/root creation */
2019                 nfs_clone_super(s, data->sb);
2020         }
2021
2022         mntroot = nfs_get_root(s, data->fh);
2023         if (IS_ERR(mntroot)) {
2024                 error = PTR_ERR(mntroot);
2025                 goto error_splat_super;
2026         }
2027         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2028                 dput(mntroot);
2029                 error = -ESTALE;
2030                 goto error_splat_super;
2031         }
2032
2033         s->s_flags |= MS_ACTIVE;
2034         mnt->mnt_sb = s;
2035         mnt->mnt_root = mntroot;
2036
2037         /* clone any lsm security options from the parent to the new sb */
2038         security_sb_clone_mnt_opts(data->sb, s);
2039
2040         dprintk("<-- nfs_xdev_get_sb() = 0\n");
2041         return 0;
2042
2043 out_err_nosb:
2044         nfs_free_server(server);
2045 out_err_noserver:
2046         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
2047         return error;
2048
2049 error_splat_super:
2050         up_write(&s->s_umount);
2051         deactivate_super(s);
2052         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
2053         return error;
2054 }
2055
2056 #ifdef CONFIG_NFS_V4
2057
2058 /*
2059  * Finish setting up a cloned NFS4 superblock
2060  */
2061 static void nfs4_clone_super(struct super_block *sb,
2062                             const struct super_block *old_sb)
2063 {
2064         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2065         sb->s_blocksize = old_sb->s_blocksize;
2066         sb->s_maxbytes = old_sb->s_maxbytes;
2067         sb->s_time_gran = 1;
2068         sb->s_op = old_sb->s_op;
2069         nfs_initialise_sb(sb);
2070 }
2071
2072 /*
2073  * Set up an NFS4 superblock
2074  */
2075 static void nfs4_fill_super(struct super_block *sb)
2076 {
2077         sb->s_time_gran = 1;
2078         sb->s_op = &nfs4_sops;
2079         nfs_initialise_sb(sb);
2080 }
2081
2082 /*
2083  * Validate NFSv4 mount options
2084  */
2085 static int nfs4_validate_mount_data(void *options,
2086                                     struct nfs_parsed_mount_data *args,
2087                                     const char *dev_name)
2088 {
2089         struct sockaddr_in *ap;
2090         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2091         char *c;
2092
2093         if (data == NULL)
2094                 goto out_no_data;
2095
2096         args->rsize             = NFS_MAX_FILE_IO_SIZE;
2097         args->wsize             = NFS_MAX_FILE_IO_SIZE;
2098         args->timeo             = 600;
2099         args->retrans           = 2;
2100         args->acregmin          = 3;
2101         args->acregmax          = 60;
2102         args->acdirmin          = 30;
2103         args->acdirmax          = 60;
2104         args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
2105         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
2106
2107         switch (data->version) {
2108         case 1:
2109                 ap = (struct sockaddr_in *)&args->nfs_server.address;
2110                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2111                         goto out_no_address;
2112                 if (data->host_addrlen == 0)
2113                         goto out_no_address;
2114                 args->nfs_server.addrlen = data->host_addrlen;
2115                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
2116                         return -EFAULT;
2117                 if (!nfs_verify_server_address((struct sockaddr *)
2118                                                 &args->nfs_server.address))
2119                         goto out_no_address;
2120
2121                 switch (data->auth_flavourlen) {
2122                 case 0:
2123                         args->auth_flavors[0] = RPC_AUTH_UNIX;
2124                         break;
2125                 case 1:
2126                         if (copy_from_user(&args->auth_flavors[0],
2127                                            data->auth_flavours,
2128                                            sizeof(args->auth_flavors[0])))
2129                                 return -EFAULT;
2130                         break;
2131                 default:
2132                         goto out_inval_auth;
2133                 }
2134
2135                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2136                 if (IS_ERR(c))
2137                         return PTR_ERR(c);
2138                 args->nfs_server.hostname = c;
2139
2140                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2141                 if (IS_ERR(c))
2142                         return PTR_ERR(c);
2143                 args->nfs_server.export_path = c;
2144                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2145
2146                 c = strndup_user(data->client_addr.data, 16);
2147                 if (IS_ERR(c))
2148                         return PTR_ERR(c);
2149                 args->client_address = c;
2150
2151                 /*
2152                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2153                  * can deal with.
2154                  */
2155
2156                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2157                 args->rsize     = data->rsize;
2158                 args->wsize     = data->wsize;
2159                 args->timeo     = data->timeo;
2160                 args->retrans   = data->retrans;
2161                 args->acregmin  = data->acregmin;
2162                 args->acregmax  = data->acregmax;
2163                 args->acdirmin  = data->acdirmin;
2164                 args->acdirmax  = data->acdirmax;
2165                 args->nfs_server.protocol = data->proto;
2166
2167                 break;
2168         default: {
2169                 int status;
2170
2171                 if (nfs_parse_mount_options((char *)options, args) == 0)
2172                         return -EINVAL;
2173
2174                 if (!nfs_verify_server_address((struct sockaddr *)
2175                                                 &args->nfs_server.address))
2176                         return -EINVAL;
2177
2178                 switch (args->auth_flavor_len) {
2179                 case 0:
2180                         args->auth_flavors[0] = RPC_AUTH_UNIX;
2181                         break;
2182                 case 1:
2183                         break;
2184                 default:
2185                         goto out_inval_auth;
2186                 }
2187
2188                 if (args->client_address == NULL)
2189                         goto out_no_client_address;
2190
2191                 status = nfs_parse_devname(dev_name,
2192                                            &args->nfs_server.hostname,
2193                                            NFS4_MAXNAMLEN,
2194                                            &args->nfs_server.export_path,
2195                                            NFS4_MAXPATHLEN);
2196                 if (status < 0)
2197                         return status;
2198
2199                 break;
2200                 }
2201         }
2202
2203         return 0;
2204
2205 out_no_data:
2206         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2207         return -EINVAL;
2208
2209 out_inval_auth:
2210         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2211                  data->auth_flavourlen);
2212         return -EINVAL;
2213
2214 out_no_address:
2215         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2216         return -EINVAL;
2217
2218 out_no_client_address:
2219         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
2220         return -EINVAL;
2221 }
2222
2223 /*
2224  * Get the superblock for an NFS4 mountpoint
2225  */
2226 static int nfs4_get_sb(struct file_system_type *fs_type,
2227         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
2228 {
2229         struct nfs_parsed_mount_data *data;
2230         struct super_block *s;
2231         struct nfs_server *server;
2232         struct nfs_fh *mntfh;
2233         struct dentry *mntroot;
2234         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2235         struct nfs_sb_mountdata sb_mntdata = {
2236                 .mntflags = flags,
2237         };
2238         int error = -ENOMEM;
2239
2240         data = kzalloc(sizeof(*data), GFP_KERNEL);
2241         mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
2242         if (data == NULL || mntfh == NULL)
2243                 goto out_free_fh;
2244
2245         security_init_mnt_opts(&data->lsm_opts);
2246
2247         /* Validate the mount data */
2248         error = nfs4_validate_mount_data(raw_data, data, dev_name);
2249         if (error < 0)
2250                 goto out;
2251
2252         /* Get a volume representation */
2253         server = nfs4_create_server(data, mntfh);
2254         if (IS_ERR(server)) {
2255                 error = PTR_ERR(server);
2256                 goto out;
2257         }
2258         sb_mntdata.server = server;
2259
2260         if (server->flags & NFS4_MOUNT_UNSHARED)
2261                 compare_super = NULL;
2262
2263         /* Get a superblock - note that we may end up sharing one that already exists */
2264         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
2265         if (IS_ERR(s)) {
2266                 error = PTR_ERR(s);
2267                 goto out_free;
2268         }
2269
2270         if (s->s_fs_info != server) {
2271                 nfs_free_server(server);
2272                 server = NULL;
2273         } else {
2274                 error = nfs_bdi_register(server);
2275                 if (error)
2276                         goto error_splat_super;
2277         }
2278
2279         if (!s->s_root) {
2280                 /* initial superblock/root creation */
2281                 nfs4_fill_super(s);
2282         }
2283
2284         mntroot = nfs4_get_root(s, mntfh);
2285         if (IS_ERR(mntroot)) {
2286                 error = PTR_ERR(mntroot);
2287                 goto error_splat_super;
2288         }
2289
2290         error = security_sb_set_mnt_opts(s, &data->lsm_opts);
2291         if (error)
2292                 goto error_splat_root;
2293
2294         s->s_flags |= MS_ACTIVE;
2295         mnt->mnt_sb = s;
2296         mnt->mnt_root = mntroot;
2297         error = 0;
2298
2299 out:
2300         kfree(data->client_address);
2301         kfree(data->nfs_server.export_path);
2302         kfree(data->nfs_server.hostname);
2303         security_free_mnt_opts(&data->lsm_opts);
2304 out_free_fh:
2305         kfree(mntfh);
2306         kfree(data);
2307         return error;
2308
2309 out_free:
2310         nfs_free_server(server);
2311         goto out;
2312
2313 error_splat_root:
2314         dput(mntroot);
2315 error_splat_super:
2316         up_write(&s->s_umount);
2317         deactivate_super(s);
2318         goto out;
2319 }
2320
2321 static void nfs4_kill_super(struct super_block *sb)
2322 {
2323         struct nfs_server *server = NFS_SB(sb);
2324
2325         nfs_return_all_delegations(sb);
2326         kill_anon_super(sb);
2327
2328         nfs4_renewd_prepare_shutdown(server);
2329         nfs_free_server(server);
2330 }
2331
2332 /*
2333  * Clone an NFS4 server record on xdev traversal (FSID-change)
2334  */
2335 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
2336                             const char *dev_name, void *raw_data,
2337                             struct vfsmount *mnt)
2338 {
2339         struct nfs_clone_mount *data = raw_data;
2340         struct super_block *s;
2341         struct nfs_server *server;
2342         struct dentry *mntroot;
2343         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2344         struct nfs_sb_mountdata sb_mntdata = {
2345                 .mntflags = flags,
2346         };
2347         int error;
2348
2349         dprintk("--> nfs4_xdev_get_sb()\n");
2350
2351         /* create a new volume representation */
2352         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
2353         if (IS_ERR(server)) {
2354                 error = PTR_ERR(server);
2355                 goto out_err_noserver;
2356         }
2357         sb_mntdata.server = server;
2358
2359         if (server->flags & NFS4_MOUNT_UNSHARED)
2360                 compare_super = NULL;
2361
2362         /* Get a superblock - note that we may end up sharing one that already exists */
2363         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2364         if (IS_ERR(s)) {
2365                 error = PTR_ERR(s);
2366                 goto out_err_nosb;
2367         }
2368
2369         if (s->s_fs_info != server) {
2370                 nfs_free_server(server);
2371                 server = NULL;
2372         } else {
2373                 error = nfs_bdi_register(server);
2374                 if (error)
2375                         goto error_splat_super;
2376         }
2377
2378         if (!s->s_root) {
2379                 /* initial superblock/root creation */
2380                 nfs4_clone_super(s, data->sb);
2381         }
2382
2383         mntroot = nfs4_get_root(s, data->fh);
2384         if (IS_ERR(mntroot)) {
2385                 error = PTR_ERR(mntroot);
2386                 goto error_splat_super;
2387         }
2388         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2389                 dput(mntroot);
2390                 error = -ESTALE;
2391                 goto error_splat_super;
2392         }
2393
2394         s->s_flags |= MS_ACTIVE;
2395         mnt->mnt_sb = s;
2396         mnt->mnt_root = mntroot;
2397
2398         security_sb_clone_mnt_opts(data->sb, s);
2399
2400         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
2401         return 0;
2402
2403 out_err_nosb:
2404         nfs_free_server(server);
2405 out_err_noserver:
2406         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
2407         return error;
2408
2409 error_splat_super:
2410         up_write(&s->s_umount);
2411         deactivate_super(s);
2412         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
2413         return error;
2414 }
2415
2416 /*
2417  * Create an NFS4 server record on referral traversal
2418  */
2419 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2420                                 const char *dev_name, void *raw_data,
2421                                 struct vfsmount *mnt)
2422 {
2423         struct nfs_clone_mount *data = raw_data;
2424         struct super_block *s;
2425         struct nfs_server *server;
2426         struct dentry *mntroot;
2427         struct nfs_fh mntfh;
2428         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2429         struct nfs_sb_mountdata sb_mntdata = {
2430                 .mntflags = flags,
2431         };
2432         int error;
2433
2434         dprintk("--> nfs4_referral_get_sb()\n");
2435
2436         /* create a new volume representation */
2437         server = nfs4_create_referral_server(data, &mntfh);
2438         if (IS_ERR(server)) {
2439                 error = PTR_ERR(server);
2440                 goto out_err_noserver;
2441         }
2442         sb_mntdata.server = server;
2443
2444         if (server->flags & NFS4_MOUNT_UNSHARED)
2445                 compare_super = NULL;
2446
2447         /* Get a superblock - note that we may end up sharing one that already exists */
2448         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2449         if (IS_ERR(s)) {
2450                 error = PTR_ERR(s);
2451                 goto out_err_nosb;
2452         }
2453
2454         if (s->s_fs_info != server) {
2455                 nfs_free_server(server);
2456                 server = NULL;
2457         } else {
2458                 error = nfs_bdi_register(server);
2459                 if (error)
2460                         goto error_splat_super;
2461         }
2462
2463         if (!s->s_root) {
2464                 /* initial superblock/root creation */
2465                 nfs4_fill_super(s);
2466         }
2467
2468         mntroot = nfs4_get_root(s, &mntfh);
2469         if (IS_ERR(mntroot)) {
2470                 error = PTR_ERR(mntroot);
2471                 goto error_splat_super;
2472         }
2473         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2474                 dput(mntroot);
2475                 error = -ESTALE;
2476                 goto error_splat_super;
2477         }
2478
2479         s->s_flags |= MS_ACTIVE;
2480         mnt->mnt_sb = s;
2481         mnt->mnt_root = mntroot;
2482
2483         security_sb_clone_mnt_opts(data->sb, s);
2484
2485         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2486         return 0;
2487
2488 out_err_nosb:
2489         nfs_free_server(server);
2490 out_err_noserver:
2491         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2492         return error;
2493
2494 error_splat_super:
2495         up_write(&s->s_umount);
2496         deactivate_super(s);
2497         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2498         return error;
2499 }
2500
2501 #endif /* CONFIG_NFS_V4 */