fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/smp_lock.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <net/ipv6.h>
  50 #include <linux/nfs_xdr.h>
  51 #include <linux/magic.h>
  52 #include <linux/parser.h>
  53
  54 #include <asm/system.h>
  55 #include <asm/uaccess.h>
  56
  57 #include "nfs4_fs.h"
  58 #include "callback.h"
  59 #include "delegation.h"
  60 #include "iostat.h"
  61 #include "internal.h"
  62
  63 #define NFSDBG_FACILITY         NFSDBG_VFS
  64
  65 enum {
  66         /* Mount options that take no arguments */
  67         Opt_soft, Opt_hard,
  68         Opt_intr, Opt_nointr,
  69         Opt_posix, Opt_noposix,
  70         Opt_cto, Opt_nocto,
  71         Opt_ac, Opt_noac,
  72         Opt_lock, Opt_nolock,
  73         Opt_v2, Opt_v3,
  74         Opt_udp, Opt_tcp, Opt_rdma,
  75         Opt_acl, Opt_noacl,
  76         Opt_rdirplus, Opt_nordirplus,
  77         Opt_sharecache, Opt_nosharecache,
  78
  79         /* Mount options that take integer arguments */
  80         Opt_port,
  81         Opt_rsize, Opt_wsize, Opt_bsize,
  82         Opt_timeo, Opt_retrans,
  83         Opt_acregmin, Opt_acregmax,
  84         Opt_acdirmin, Opt_acdirmax,
  85         Opt_actimeo,
  86         Opt_namelen,
  87         Opt_mountport,
  88         Opt_mountvers,
  89         Opt_nfsvers,
  90
  91         /* Mount options that take string arguments */
  92         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
  93         Opt_addr, Opt_mountaddr, Opt_clientaddr,
  94
  95         /* Mount options that are ignored */
  96         Opt_userspace, Opt_deprecated,
  97
  98         Opt_err
  99 };
 100
 101 static match_table_t nfs_mount_option_tokens = {
 102         { Opt_userspace, "bg" },
 103         { Opt_userspace, "fg" },
 104         { Opt_soft, "soft" },
 105         { Opt_hard, "hard" },
 106         { Opt_intr, "intr" },
 107         { Opt_nointr, "nointr" },
 108         { Opt_posix, "posix" },
 109         { Opt_noposix, "noposix" },
 110         { Opt_cto, "cto" },
 111         { Opt_nocto, "nocto" },
 112         { Opt_ac, "ac" },
 113         { Opt_noac, "noac" },
 114         { Opt_lock, "lock" },
 115         { Opt_nolock, "nolock" },
 116         { Opt_v2, "v2" },
 117         { Opt_v3, "v3" },
 118         { Opt_udp, "udp" },
 119         { Opt_tcp, "tcp" },
 120         { Opt_rdma, "rdma" },
 121         { Opt_acl, "acl" },
 122         { Opt_noacl, "noacl" },
 123         { Opt_rdirplus, "rdirplus" },
 124         { Opt_nordirplus, "nordirplus" },
 125         { Opt_sharecache, "sharecache" },
 126         { Opt_nosharecache, "nosharecache" },
 127
 128         { Opt_port, "port=%u" },
 129         { Opt_rsize, "rsize=%u" },
 130         { Opt_wsize, "wsize=%u" },
 131         { Opt_bsize, "bsize=%u" },
 132         { Opt_timeo, "timeo=%u" },
 133         { Opt_retrans, "retrans=%u" },
 134         { Opt_acregmin, "acregmin=%u" },
 135         { Opt_acregmax, "acregmax=%u" },
 136         { Opt_acdirmin, "acdirmin=%u" },
 137         { Opt_acdirmax, "acdirmax=%u" },
 138         { Opt_actimeo, "actimeo=%u" },
 139         { Opt_userspace, "retry=%u" },
 140         { Opt_namelen, "namlen=%u" },
 141         { Opt_mountport, "mountport=%u" },
 142         { Opt_mountvers, "mountvers=%u" },
 143         { Opt_nfsvers, "nfsvers=%u" },
 144         { Opt_nfsvers, "vers=%u" },
 145
 146         { Opt_sec, "sec=%s" },
 147         { Opt_proto, "proto=%s" },
 148         { Opt_mountproto, "mountproto=%s" },
 149         { Opt_addr, "addr=%s" },
 150         { Opt_clientaddr, "clientaddr=%s" },
 151         { Opt_mounthost, "mounthost=%s" },
 152         { Opt_mountaddr, "mountaddr=%s" },
 153
 154         { Opt_err, NULL }
 155 };
 156
 157 enum {
 158         Opt_xprt_udp, Opt_xprt_tcp, Opt_xprt_rdma,
 159
 160         Opt_xprt_err
 161 };
 162
 163 static match_table_t nfs_xprt_protocol_tokens = {
 164         { Opt_xprt_udp, "udp" },
 165         { Opt_xprt_tcp, "tcp" },
 166         { Opt_xprt_rdma, "rdma" },
 167
 168         { Opt_xprt_err, NULL }
 169 };
 170
 171 enum {
 172         Opt_sec_none, Opt_sec_sys,
 173         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 174         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 175         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 176
 177         Opt_sec_err
 178 };
 179
 180 static match_table_t nfs_secflavor_tokens = {
 181         { Opt_sec_none, "none" },
 182         { Opt_sec_none, "null" },
 183         { Opt_sec_sys, "sys" },
 184
 185         { Opt_sec_krb5, "krb5" },
 186         { Opt_sec_krb5i, "krb5i" },
 187         { Opt_sec_krb5p, "krb5p" },
 188
 189         { Opt_sec_lkey, "lkey" },
 190         { Opt_sec_lkeyi, "lkeyi" },
 191         { Opt_sec_lkeyp, "lkeyp" },
 192
 193         { Opt_sec_err, NULL }
 194 };
 195
 196
 197 static void nfs_umount_begin(struct vfsmount *, int);
 198 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 199 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 200 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 201 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 202 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 203                 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 204 static void nfs_kill_super(struct super_block *);
 205 static void nfs_put_super(struct super_block *);
 206
 207 static struct file_system_type nfs_fs_type = {
 208         .owner          = THIS_MODULE,
 209         .name           = "nfs",
 210         .get_sb         = nfs_get_sb,
 211         .kill_sb        = nfs_kill_super,
 212         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 213 };
 214
 215 struct file_system_type nfs_xdev_fs_type = {
 216         .owner          = THIS_MODULE,
 217         .name           = "nfs",
 218         .get_sb         = nfs_xdev_get_sb,
 219         .kill_sb        = nfs_kill_super,
 220         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 221 };
 222
 223 static const struct super_operations nfs_sops = {
 224         .alloc_inode    = nfs_alloc_inode,
 225         .destroy_inode  = nfs_destroy_inode,
 226         .write_inode    = nfs_write_inode,
 227         .put_super      = nfs_put_super,
 228         .statfs         = nfs_statfs,
 229         .clear_inode    = nfs_clear_inode,
 230         .umount_begin   = nfs_umount_begin,
 231         .show_options   = nfs_show_options,
 232         .show_stats     = nfs_show_stats,
 233 };
 234
 235 #ifdef CONFIG_NFS_V4
 236 static int nfs4_get_sb(struct file_system_type *fs_type,
 237         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 238 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
 239         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 240 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
 241         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 242 static void nfs4_kill_super(struct super_block *sb);
 243
 244 static struct file_system_type nfs4_fs_type = {
 245         .owner          = THIS_MODULE,
 246         .name           = "nfs4",
 247         .get_sb         = nfs4_get_sb,
 248         .kill_sb        = nfs4_kill_super,
 249         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 250 };
 251
 252 struct file_system_type nfs4_xdev_fs_type = {
 253         .owner          = THIS_MODULE,
 254         .name           = "nfs4",
 255         .get_sb         = nfs4_xdev_get_sb,
 256         .kill_sb        = nfs4_kill_super,
 257         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 258 };
 259
 260 struct file_system_type nfs4_referral_fs_type = {
 261         .owner          = THIS_MODULE,
 262         .name           = "nfs4",
 263         .get_sb         = nfs4_referral_get_sb,
 264         .kill_sb        = nfs4_kill_super,
 265         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 266 };
 267
 268 static const struct super_operations nfs4_sops = {
 269         .alloc_inode    = nfs_alloc_inode,
 270         .destroy_inode  = nfs_destroy_inode,
 271         .write_inode    = nfs_write_inode,
 272         .statfs         = nfs_statfs,
 273         .clear_inode    = nfs4_clear_inode,
 274         .umount_begin   = nfs_umount_begin,
 275         .show_options   = nfs_show_options,
 276         .show_stats     = nfs_show_stats,
 277 };
 278 #endif
 279
 280 static struct shrinker acl_shrinker = {
 281         .shrink         = nfs_access_cache_shrinker,
 282         .seeks          = DEFAULT_SEEKS,
 283 };
 284
 285 /*
 286  * Register the NFS filesystems
 287  */
 288 int __init register_nfs_fs(void)
 289 {
 290         int ret;
 291
 292         ret = register_filesystem(&nfs_fs_type);
 293         if (ret < 0)
 294                 goto error_0;
 295
 296         ret = nfs_register_sysctl();
 297         if (ret < 0)
 298                 goto error_1;
 299 #ifdef CONFIG_NFS_V4
 300         ret = register_filesystem(&nfs4_fs_type);
 301         if (ret < 0)
 302                 goto error_2;
 303 #endif
 304         register_shrinker(&acl_shrinker);
 305         return 0;
 306
 307 #ifdef CONFIG_NFS_V4
 308 error_2:
 309         nfs_unregister_sysctl();
 310 #endif
 311 error_1:
 312         unregister_filesystem(&nfs_fs_type);
 313 error_0:
 314         return ret;
 315 }
 316
 317 /*
 318  * Unregister the NFS filesystems
 319  */
 320 void __exit unregister_nfs_fs(void)
 321 {
 322         unregister_shrinker(&acl_shrinker);
 323 #ifdef CONFIG_NFS_V4
 324         unregister_filesystem(&nfs4_fs_type);
 325 #endif
 326         nfs_unregister_sysctl();
 327         unregister_filesystem(&nfs_fs_type);
 328 }
 329
 330 void nfs_sb_active(struct nfs_server *server)
 331 {
 332         atomic_inc(&server->active);
 333 }
 334
 335 void nfs_sb_deactive(struct nfs_server *server)
 336 {
 337         if (atomic_dec_and_test(&server->active))
 338                 wake_up(&server->active_wq);
 339 }
 340
 341 static void nfs_put_super(struct super_block *sb)
 342 {
 343         struct nfs_server *server = NFS_SB(sb);
 344         /*
 345          * Make sure there are no outstanding ops to this server.
 346          * If so, wait for them to finish before allowing the
 347          * unmount to continue.
 348          */
 349         wait_event(server->active_wq, atomic_read(&server->active) == 0);
 350 }
 351
 352 /*
 353  * Deliver file system statistics to userspace
 354  */
 355 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 356 {
 357         struct nfs_server *server = NFS_SB(dentry->d_sb);
 358         unsigned char blockbits;
 359         unsigned long blockres;
 360         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 361         struct nfs_fattr fattr;
 362         struct nfs_fsstat res = {
 363                         .fattr = &fattr,
 364         };
 365         int error;
 366
 367         lock_kernel();
 368
 369         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 370         if (error < 0)
 371                 goto out_err;
 372         buf->f_type = NFS_SUPER_MAGIC;
 373
 374         /*
 375          * Current versions of glibc do not correctly handle the
 376          * case where f_frsize != f_bsize.  Eventually we want to
 377          * report the value of wtmult in this field.
 378          */
 379         buf->f_frsize = dentry->d_sb->s_blocksize;
 380
 381         /*
 382          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 383          * are reported in units of f_frsize.  Linux hasn't had
 384          * an f_frsize field in its statfs struct until recently,
 385          * thus historically Linux's sys_statfs reports these
 386          * fields in units of f_bsize.
 387          */
 388         buf->f_bsize = dentry->d_sb->s_blocksize;
 389         blockbits = dentry->d_sb->s_blocksize_bits;
 390         blockres = (1 << blockbits) - 1;
 391         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 392         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 393         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 394
 395         buf->f_files = res.tfiles;
 396         buf->f_ffree = res.afiles;
 397
 398         buf->f_namelen = server->namelen;
 399
 400         unlock_kernel();
 401         return 0;
 402
 403  out_err:
 404         dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
 405         unlock_kernel();
 406         return error;
 407 }
 408
 409 /*
 410  * Map the security flavour number to a name
 411  */
 412 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 413 {
 414         static const struct {
 415                 rpc_authflavor_t flavour;
 416                 const char *str;
 417         } sec_flavours[] = {
 418                 { RPC_AUTH_NULL, "null" },
 419                 { RPC_AUTH_UNIX, "sys" },
 420                 { RPC_AUTH_GSS_KRB5, "krb5" },
 421                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 422                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 423                 { RPC_AUTH_GSS_LKEY, "lkey" },
 424                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 425                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 426                 { RPC_AUTH_GSS_SPKM, "spkm" },
 427                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 428                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 429                 { UINT_MAX, "unknown" }
 430         };
 431         int i;
 432
 433         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 434                 if (sec_flavours[i].flavour == flavour)
 435                         break;
 436         }
 437         return sec_flavours[i].str;
 438 }
 439
 440 /*
 441  * Describe the mount options in force on this server representation
 442  */
 443 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
 444 {
 445         static const struct proc_nfs_info {
 446                 int flag;
 447                 const char *str;
 448                 const char *nostr;
 449         } nfs_info[] = {
 450                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 451                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 452                 { NFS_MOUNT_NOAC, ",noac", "" },
 453                 { NFS_MOUNT_NONLM, ",nolock", "" },
 454                 { NFS_MOUNT_NOACL, ",noacl", "" },
 455                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 456                 { NFS_MOUNT_UNSHARED, ",nosharecache", ""},
 457                 { 0, NULL, NULL }
 458         };
 459         const struct proc_nfs_info *nfs_infop;
 460         struct nfs_client *clp = nfss->nfs_client;
 461
 462         seq_printf(m, ",vers=%d", clp->rpc_ops->version);
 463         seq_printf(m, ",rsize=%d", nfss->rsize);
 464         seq_printf(m, ",wsize=%d", nfss->wsize);
 465         if (nfss->acregmin != 3*HZ || showdefaults)
 466                 seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
 467         if (nfss->acregmax != 60*HZ || showdefaults)
 468                 seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
 469         if (nfss->acdirmin != 30*HZ || showdefaults)
 470                 seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
 471         if (nfss->acdirmax != 60*HZ || showdefaults)
 472                 seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
 473         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 474                 if (nfss->flags & nfs_infop->flag)
 475                         seq_puts(m, nfs_infop->str);
 476                 else
 477                         seq_puts(m, nfs_infop->nostr);
 478         }
 479         seq_printf(m, ",proto=%s",
 480                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_PROTO));
 481         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 482         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 483         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 484 }
 485
 486 /*
 487  * Describe the mount options on this VFS mountpoint
 488  */
 489 static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 490 {
 491         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 492
 493         nfs_show_mount_options(m, nfss, 0);
 494
 495         seq_printf(m, ",addr=%s",
 496                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 497                                                         RPC_DISPLAY_ADDR));
 498
 499         return 0;
 500 }
 501
 502 /*
 503  * Present statistical information for this VFS mountpoint
 504  */
 505 static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 506 {
 507         int i, cpu;
 508         struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
 509         struct rpc_auth *auth = nfss->client->cl_auth;
 510         struct nfs_iostats totals = { };
 511
 512         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 513
 514         /*
 515          * Display all mount option settings
 516          */
 517         seq_printf(m, "\n\topts:\t");
 518         seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 519         seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 520         seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 521         seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 522         nfs_show_mount_options(m, nfss, 1);
 523
 524         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 525
 526         seq_printf(m, "\n\tcaps:\t");
 527         seq_printf(m, "caps=0x%x", nfss->caps);
 528         seq_printf(m, ",wtmult=%d", nfss->wtmult);
 529         seq_printf(m, ",dtsize=%d", nfss->dtsize);
 530         seq_printf(m, ",bsize=%d", nfss->bsize);
 531         seq_printf(m, ",namelen=%d", nfss->namelen);
 532
 533 #ifdef CONFIG_NFS_V4
 534         if (nfss->nfs_client->rpc_ops->version == 4) {
 535                 seq_printf(m, "\n\tnfsv4:\t");
 536                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 537                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 538                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 539         }
 540 #endif
 541
 542         /*
 543          * Display security flavor in effect for this mount
 544          */
 545         seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
 546         if (auth->au_flavor)
 547                 seq_printf(m, ",pseudoflavor=%d", auth->au_flavor);
 548
 549         /*
 550          * Display superblock I/O counters
 551          */
 552         for_each_possible_cpu(cpu) {
 553                 struct nfs_iostats *stats;
 554
 555                 preempt_disable();
 556                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 557
 558                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 559                         totals.events[i] += stats->events[i];
 560                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 561                         totals.bytes[i] += stats->bytes[i];
 562
 563                 preempt_enable();
 564         }
 565
 566         seq_printf(m, "\n\tevents:\t");
 567         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 568                 seq_printf(m, "%lu ", totals.events[i]);
 569         seq_printf(m, "\n\tbytes:\t");
 570         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 571                 seq_printf(m, "%Lu ", totals.bytes[i]);
 572         seq_printf(m, "\n");
 573
 574         rpc_print_iostats(m, nfss->client);
 575
 576         return 0;
 577 }
 578
 579 /*
 580  * Begin unmount by attempting to remove all automounted mountpoints we added
 581  * in response to xdev traversals and referrals
 582  */
 583 static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
 584 {
 585         struct nfs_server *server = NFS_SB(vfsmnt->mnt_sb);
 586         struct rpc_clnt *rpc;
 587
 588         shrink_submounts(vfsmnt, &nfs_automount_list);
 589
 590         if (!(flags & MNT_FORCE))
 591                 return;
 592         /* -EIO all pending I/O */
 593         rpc = server->client_acl;
 594         if (!IS_ERR(rpc))
 595                 rpc_killall_tasks(rpc);
 596         rpc = server->client;
 597         if (!IS_ERR(rpc))
 598                 rpc_killall_tasks(rpc);
 599 }
 600
 601 /*
 602  * Set the port number in an address.  Be agnostic about the address family.
 603  */
 604 static void nfs_set_port(struct sockaddr *sap, unsigned short port)
 605 {
 606         switch (sap->sa_family) {
 607         case AF_INET: {
 608                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 609                 ap->sin_port = htons(port);
 610                 break;
 611         }
 612         case AF_INET6: {
 613                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 614                 ap->sin6_port = htons(port);
 615                 break;
 616         }
 617         }
 618 }
 619
 620 /*
 621  * Sanity-check a server address provided by the mount command.
 622  *
 623  * Address family must be initialized, and address must not be
 624  * the ANY address for that family.
 625  */
 626 static int nfs_verify_server_address(struct sockaddr *addr)
 627 {
 628         switch (addr->sa_family) {
 629         case AF_INET: {
 630                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 631                 return sa->sin_addr.s_addr != INADDR_ANY;
 632         }
 633         case AF_INET6: {
 634                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 635                 return !ipv6_addr_any(sa);
 636         }
 637         }
 638
 639         return 0;
 640 }
 641
 642 /*
 643  * Parse string addresses passed in via a mount option,
 644  * and construct a sockaddr based on the result.
 645  *
 646  * If address parsing fails, set the sockaddr's address
 647  * family to AF_UNSPEC to force nfs_verify_server_address()
 648  * to punt the mount.
 649  */
 650 static void nfs_parse_server_address(char *value,
 651                                      struct sockaddr *sap,
 652                                      size_t *len)
 653 {
 654         if (strchr(value, ':')) {
 655                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
 656                 u8 *addr = (u8 *)&ap->sin6_addr.in6_u;
 657
 658                 ap->sin6_family = AF_INET6;
 659                 *len = sizeof(*ap);
 660                 if (in6_pton(value, -1, addr, '\0', NULL))
 661                         return;
 662         } else {
 663                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
 664                 u8 *addr = (u8 *)&ap->sin_addr.s_addr;
 665
 666                 ap->sin_family = AF_INET;
 667                 *len = sizeof(*ap);
 668                 if (in4_pton(value, -1, addr, '\0', NULL))
 669                         return;
 670         }
 671
 672         sap->sa_family = AF_UNSPEC;
 673         *len = 0;
 674 }
 675
 676 /*
 677  * Error-check and convert a string of mount options from user space into
 678  * a data structure
 679  */
 680 static int nfs_parse_mount_options(char *raw,
 681                                    struct nfs_parsed_mount_data *mnt)
 682 {
 683         char *p, *string;
 684         unsigned short port = 0;
 685
 686         if (!raw) {
 687                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
 688                 return 1;
 689         }
 690         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
 691
 692         while ((p = strsep(&raw, ",")) != NULL) {
 693                 substring_t args[MAX_OPT_ARGS];
 694                 int option, token;
 695
 696                 if (!*p)
 697                         continue;
 698
 699                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
 700
 701                 token = match_token(p, nfs_mount_option_tokens, args);
 702                 switch (token) {
 703                 case Opt_soft:
 704                         mnt->flags |= NFS_MOUNT_SOFT;
 705                         break;
 706                 case Opt_hard:
 707                         mnt->flags &= ~NFS_MOUNT_SOFT;
 708                         break;
 709                 case Opt_intr:
 710                 case Opt_nointr:
 711                         break;
 712                 case Opt_posix:
 713                         mnt->flags |= NFS_MOUNT_POSIX;
 714                         break;
 715                 case Opt_noposix:
 716                         mnt->flags &= ~NFS_MOUNT_POSIX;
 717                         break;
 718                 case Opt_cto:
 719                         mnt->flags &= ~NFS_MOUNT_NOCTO;
 720                         break;
 721                 case Opt_nocto:
 722                         mnt->flags |= NFS_MOUNT_NOCTO;
 723                         break;
 724                 case Opt_ac:
 725                         mnt->flags &= ~NFS_MOUNT_NOAC;
 726                         break;
 727                 case Opt_noac:
 728                         mnt->flags |= NFS_MOUNT_NOAC;
 729                         break;
 730                 case Opt_lock:
 731                         mnt->flags &= ~NFS_MOUNT_NONLM;
 732                         break;
 733                 case Opt_nolock:
 734                         mnt->flags |= NFS_MOUNT_NONLM;
 735                         break;
 736                 case Opt_v2:
 737                         mnt->flags &= ~NFS_MOUNT_VER3;
 738                         break;
 739                 case Opt_v3:
 740                         mnt->flags |= NFS_MOUNT_VER3;
 741                         break;
 742                 case Opt_udp:
 743                         mnt->flags &= ~NFS_MOUNT_TCP;
 744                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 745                         mnt->timeo = 7;
 746                         mnt->retrans = 5;
 747                         break;
 748                 case Opt_tcp:
 749                         mnt->flags |= NFS_MOUNT_TCP;
 750                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 751                         mnt->timeo = 600;
 752                         mnt->retrans = 2;
 753                         break;
 754                 case Opt_rdma:
 755                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
 756                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 757                         mnt->timeo = 600;
 758                         mnt->retrans = 2;
 759                         break;
 760                 case Opt_acl:
 761                         mnt->flags &= ~NFS_MOUNT_NOACL;
 762                         break;
 763                 case Opt_noacl:
 764                         mnt->flags |= NFS_MOUNT_NOACL;
 765                         break;
 766                 case Opt_rdirplus:
 767                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
 768                         break;
 769                 case Opt_nordirplus:
 770                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
 771                         break;
 772                 case Opt_sharecache:
 773                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
 774                         break;
 775                 case Opt_nosharecache:
 776                         mnt->flags |= NFS_MOUNT_UNSHARED;
 777                         break;
 778
 779                 case Opt_port:
 780                         if (match_int(args, &option))
 781                                 return 0;
 782                         if (option < 0 || option > 65535)
 783                                 return 0;
 784                         port = option;
 785                         break;
 786                 case Opt_rsize:
 787                         if (match_int(args, &mnt->rsize))
 788                                 return 0;
 789                         break;
 790                 case Opt_wsize:
 791                         if (match_int(args, &mnt->wsize))
 792                                 return 0;
 793                         break;
 794                 case Opt_bsize:
 795                         if (match_int(args, &option))
 796                                 return 0;
 797                         if (option < 0)
 798                                 return 0;
 799                         mnt->bsize = option;
 800                         break;
 801                 case Opt_timeo:
 802                         if (match_int(args, &mnt->timeo))
 803                                 return 0;
 804                         break;
 805                 case Opt_retrans:
 806                         if (match_int(args, &mnt->retrans))
 807                                 return 0;
 808                         break;
 809                 case Opt_acregmin:
 810                         if (match_int(args, &mnt->acregmin))
 811                                 return 0;
 812                         break;
 813                 case Opt_acregmax:
 814                         if (match_int(args, &mnt->acregmax))
 815                                 return 0;
 816                         break;
 817                 case Opt_acdirmin:
 818                         if (match_int(args, &mnt->acdirmin))
 819                                 return 0;
 820                         break;
 821                 case Opt_acdirmax:
 822                         if (match_int(args, &mnt->acdirmax))
 823                                 return 0;
 824                         break;
 825                 case Opt_actimeo:
 826                         if (match_int(args, &option))
 827                                 return 0;
 828                         if (option < 0)
 829                                 return 0;
 830                         mnt->acregmin =
 831                         mnt->acregmax =
 832                         mnt->acdirmin =
 833                         mnt->acdirmax = option;
 834                         break;
 835                 case Opt_namelen:
 836                         if (match_int(args, &mnt->namlen))
 837                                 return 0;
 838                         break;
 839                 case Opt_mountport:
 840                         if (match_int(args, &option))
 841                                 return 0;
 842                         if (option < 0 || option > 65535)
 843                                 return 0;
 844                         mnt->mount_server.port = option;
 845                         break;
 846                 case Opt_mountvers:
 847                         if (match_int(args, &option))
 848                                 return 0;
 849                         if (option < 0)
 850                                 return 0;
 851                         mnt->mount_server.version = option;
 852                         break;
 853                 case Opt_nfsvers:
 854                         if (match_int(args, &option))
 855                                 return 0;
 856                         switch (option) {
 857                         case 2:
 858                                 mnt->flags &= ~NFS_MOUNT_VER3;
 859                                 break;
 860                         case 3:
 861                                 mnt->flags |= NFS_MOUNT_VER3;
 862                                 break;
 863                         default:
 864                                 goto out_unrec_vers;
 865                         }
 866                         break;
 867
 868                 case Opt_sec:
 869                         string = match_strdup(args);
 870                         if (string == NULL)
 871                                 goto out_nomem;
 872                         token = match_token(string, nfs_secflavor_tokens, args);
 873                         kfree(string);
 874
 875                         /*
 876                          * The flags setting is for v2/v3.  The flavor_len
 877                          * setting is for v4.  v2/v3 also need to know the
 878                          * difference between NULL and UNIX.
 879                          */
 880                         switch (token) {
 881                         case Opt_sec_none:
 882                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 883                                 mnt->auth_flavor_len = 0;
 884                                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
 885                                 break;
 886                         case Opt_sec_sys:
 887                                 mnt->flags &= ~NFS_MOUNT_SECFLAVOUR;
 888                                 mnt->auth_flavor_len = 0;
 889                                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
 890                                 break;
 891                         case Opt_sec_krb5:
 892                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 893                                 mnt->auth_flavor_len = 1;
 894                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
 895                                 break;
 896                         case Opt_sec_krb5i:
 897                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 898                                 mnt->auth_flavor_len = 1;
 899                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
 900                                 break;
 901                         case Opt_sec_krb5p:
 902                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 903                                 mnt->auth_flavor_len = 1;
 904                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
 905                                 break;
 906                         case Opt_sec_lkey:
 907                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 908                                 mnt->auth_flavor_len = 1;
 909                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
 910                                 break;
 911                         case Opt_sec_lkeyi:
 912                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 913                                 mnt->auth_flavor_len = 1;
 914                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
 915                                 break;
 916                         case Opt_sec_lkeyp:
 917                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 918                                 mnt->auth_flavor_len = 1;
 919                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
 920                                 break;
 921                         case Opt_sec_spkm:
 922                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 923                                 mnt->auth_flavor_len = 1;
 924                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
 925                                 break;
 926                         case Opt_sec_spkmi:
 927                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 928                                 mnt->auth_flavor_len = 1;
 929                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
 930                                 break;
 931                         case Opt_sec_spkmp:
 932                                 mnt->flags |= NFS_MOUNT_SECFLAVOUR;
 933                                 mnt->auth_flavor_len = 1;
 934                                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
 935                                 break;
 936                         default:
 937                                 goto out_unrec_sec;
 938                         }
 939                         break;
 940                 case Opt_proto:
 941                         string = match_strdup(args);
 942                         if (string == NULL)
 943                                 goto out_nomem;
 944                         token = match_token(string,
 945                                             nfs_xprt_protocol_tokens, args);
 946                         kfree(string);
 947
 948                         switch (token) {
 949                         case Opt_xprt_udp:
 950                                 mnt->flags &= ~NFS_MOUNT_TCP;
 951                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 952                                 mnt->timeo = 7;
 953                                 mnt->retrans = 5;
 954                                 break;
 955                         case Opt_xprt_tcp:
 956                                 mnt->flags |= NFS_MOUNT_TCP;
 957                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 958                                 mnt->timeo = 600;
 959                                 mnt->retrans = 2;
 960                                 break;
 961                         case Opt_xprt_rdma:
 962                                 /* vector side protocols to TCP */
 963                                 mnt->flags |= NFS_MOUNT_TCP;
 964                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
 965                                 mnt->timeo = 600;
 966                                 mnt->retrans = 2;
 967                                 break;
 968                         default:
 969                                 goto out_unrec_xprt;
 970                         }
 971                         break;
 972                 case Opt_mountproto:
 973                         string = match_strdup(args);
 974                         if (string == NULL)
 975                                 goto out_nomem;
 976                         token = match_token(string,
 977                                             nfs_xprt_protocol_tokens, args);
 978                         kfree(string);
 979
 980                         switch (token) {
 981                         case Opt_xprt_udp:
 982                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
 983                                 break;
 984                         case Opt_xprt_tcp:
 985                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
 986                                 break;
 987                         case Opt_xprt_rdma: /* not used for side protocols */
 988                         default:
 989                                 goto out_unrec_xprt;
 990                         }
 991                         break;
 992                 case Opt_addr:
 993                         string = match_strdup(args);
 994                         if (string == NULL)
 995                                 goto out_nomem;
 996                         nfs_parse_server_address(string, (struct sockaddr *)
 997                                                  &mnt->nfs_server.address,
 998                                                  &mnt->nfs_server.addrlen);
 999                         kfree(string);
1000                         break;
1001                 case Opt_clientaddr:
1002                         string = match_strdup(args);
1003                         if (string == NULL)
1004                                 goto out_nomem;
1005                         kfree(mnt->client_address);
1006                         mnt->client_address = string;
1007                         break;
1008                 case Opt_mounthost:
1009                         string = match_strdup(args);
1010                         if (string == NULL)
1011                                 goto out_nomem;
1012                         kfree(mnt->mount_server.hostname);
1013                         mnt->mount_server.hostname = string;
1014                         break;
1015                 case Opt_mountaddr:
1016                         string = match_strdup(args);
1017                         if (string == NULL)
1018                                 goto out_nomem;
1019                         nfs_parse_server_address(string, (struct sockaddr *)
1020                                                  &mnt->mount_server.address,
1021                                                  &mnt->mount_server.addrlen);
1022                         kfree(string);
1023                         break;
1024
1025                 case Opt_userspace:
1026                 case Opt_deprecated:
1027                         break;
1028
1029                 default:
1030                         goto out_unknown;
1031                 }
1032         }
1033
1034         nfs_set_port((struct sockaddr *)&mnt->nfs_server.address, port);
1035
1036         return 1;
1037
1038 out_nomem:
1039         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1040         return 0;
1041
1042 out_unrec_vers:
1043         printk(KERN_INFO "NFS: unrecognized NFS version number\n");
1044         return 0;
1045
1046 out_unrec_xprt:
1047         printk(KERN_INFO "NFS: unrecognized transport protocol\n");
1048         return 0;
1049
1050 out_unrec_sec:
1051         printk(KERN_INFO "NFS: unrecognized security flavor\n");
1052         return 0;
1053
1054 out_unknown:
1055         printk(KERN_INFO "NFS: unknown mount option: %s\n", p);
1056         return 0;
1057 }
1058
1059 /*
1060  * Use the remote server's MOUNT service to request the NFS file handle
1061  * corresponding to the provided path.
1062  */
1063 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
1064                          struct nfs_fh *root_fh)
1065 {
1066         struct sockaddr *sap = (struct sockaddr *)&args->mount_server.address;
1067         char *hostname;
1068         int status;
1069
1070         if (args->mount_server.version == 0) {
1071                 if (args->flags & NFS_MOUNT_VER3)
1072                         args->mount_server.version = NFS_MNT3_VERSION;
1073                 else
1074                         args->mount_server.version = NFS_MNT_VERSION;
1075         }
1076
1077         if (args->mount_server.hostname)
1078                 hostname = args->mount_server.hostname;
1079         else
1080                 hostname = args->nfs_server.hostname;
1081
1082         /*
1083          * Construct the mount server's address.
1084          */
1085         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1086                 memcpy(sap, &args->nfs_server.address,
1087                        args->nfs_server.addrlen);
1088                 args->mount_server.addrlen = args->nfs_server.addrlen;
1089         }
1090
1091         /*
1092          * autobind will be used if mount_server.port == 0
1093          */
1094         nfs_set_port(sap, args->mount_server.port);
1095
1096         /*
1097          * Now ask the mount server to map our export path
1098          * to a file handle.
1099          */
1100         status = nfs_mount(sap,
1101                            args->mount_server.addrlen,
1102                            hostname,
1103                            args->nfs_server.export_path,
1104                            args->mount_server.version,
1105                            args->mount_server.protocol,
1106                            root_fh);
1107         if (status == 0)
1108                 return 0;
1109
1110         dfprintk(MOUNT, "NFS: unable to mount server %s, error %d",
1111                         hostname, status);
1112         return status;
1113 }
1114
1115 /*
1116  * Validate the NFS2/NFS3 mount data
1117  * - fills in the mount root filehandle
1118  *
1119  * For option strings, user space handles the following behaviors:
1120  *
1121  * + DNS: mapping server host name to IP address ("addr=" option)
1122  *
1123  * + failure mode: how to behave if a mount request can't be handled
1124  *   immediately ("fg/bg" option)
1125  *
1126  * + retry: how often to retry a mount request ("retry=" option)
1127  *
1128  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1129  *   mountproto=tcp after mountproto=udp, and so on
1130  */
1131 static int nfs_validate_mount_data(void *options,
1132                                    struct nfs_parsed_mount_data *args,
1133                                    struct nfs_fh *mntfh,
1134                                    const char *dev_name)
1135 {
1136         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1137
1138         memset(args, 0, sizeof(*args));
1139
1140         if (data == NULL)
1141                 goto out_no_data;
1142
1143         args->flags             = (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
1144         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1145         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1146         args->timeo             = 600;
1147         args->retrans           = 2;
1148         args->acregmin          = 3;
1149         args->acregmax          = 60;
1150         args->acdirmin          = 30;
1151         args->acdirmax          = 60;
1152         args->mount_server.protocol = XPRT_TRANSPORT_UDP;
1153         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1154
1155         switch (data->version) {
1156         case 1:
1157                 data->namlen = 0;
1158         case 2:
1159                 data->bsize = 0;
1160         case 3:
1161                 if (data->flags & NFS_MOUNT_VER3)
1162                         goto out_no_v3;
1163                 data->root.size = NFS2_FHSIZE;
1164                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1165         case 4:
1166                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1167                         goto out_no_sec;
1168         case 5:
1169                 memset(data->context, 0, sizeof(data->context));
1170         case 6:
1171                 if (data->flags & NFS_MOUNT_VER3)
1172                         mntfh->size = data->root.size;
1173                 else
1174                         mntfh->size = NFS2_FHSIZE;
1175
1176                 if (mntfh->size > sizeof(mntfh->data))
1177                         goto out_invalid_fh;
1178
1179                 memcpy(mntfh->data, data->root.data, mntfh->size);
1180                 if (mntfh->size < sizeof(mntfh->data))
1181                         memset(mntfh->data + mntfh->size, 0,
1182                                sizeof(mntfh->data) - mntfh->size);
1183
1184                 /*
1185                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1186                  * can deal with.
1187                  */
1188                 args->flags             = data->flags;
1189                 args->rsize             = data->rsize;
1190                 args->wsize             = data->wsize;
1191                 args->flags             = data->flags;
1192                 args->timeo             = data->timeo;
1193                 args->retrans           = data->retrans;
1194                 args->acregmin          = data->acregmin;
1195                 args->acregmax          = data->acregmax;
1196                 args->acdirmin          = data->acdirmin;
1197                 args->acdirmax          = data->acdirmax;
1198
1199                 memcpy(&args->nfs_server.address, &data->addr,
1200                        sizeof(data->addr));
1201                 args->nfs_server.addrlen = sizeof(data->addr);
1202                 if (!nfs_verify_server_address((struct sockaddr *)
1203                                                 &args->nfs_server.address))
1204                         goto out_no_address;
1205
1206                 if (!(data->flags & NFS_MOUNT_TCP))
1207                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1208                 /* N.B. caller will free nfs_server.hostname in all cases */
1209                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1210                 args->namlen            = data->namlen;
1211                 args->bsize             = data->bsize;
1212                 args->auth_flavors[0]   = data->pseudoflavor;
1213                 break;
1214         default: {
1215                 unsigned int len;
1216                 char *c;
1217                 int status;
1218
1219                 if (nfs_parse_mount_options((char *)options, args) == 0)
1220                         return -EINVAL;
1221
1222                 if (!nfs_verify_server_address((struct sockaddr *)
1223                                                 &args->nfs_server.address))
1224                         goto out_no_address;
1225
1226                 c = strchr(dev_name, ':');
1227                 if (c == NULL)
1228                         return -EINVAL;
1229                 len = c - dev_name;
1230                 /* N.B. caller will free nfs_server.hostname in all cases */
1231                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1232
1233                 c++;
1234                 if (strlen(c) > NFS_MAXPATHLEN)
1235                         return -ENAMETOOLONG;
1236                 args->nfs_server.export_path = c;
1237
1238                 status = nfs_try_mount(args, mntfh);
1239                 if (status)
1240                         return status;
1241
1242                 break;
1243                 }
1244         }
1245
1246         if (!(args->flags & NFS_MOUNT_SECFLAVOUR))
1247                 args->auth_flavors[0] = RPC_AUTH_UNIX;
1248
1249 #ifndef CONFIG_NFS_V3
1250         if (args->flags & NFS_MOUNT_VER3)
1251                 goto out_v3_not_compiled;
1252 #endif /* !CONFIG_NFS_V3 */
1253
1254         return 0;
1255
1256 out_no_data:
1257         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1258         return -EINVAL;
1259
1260 out_no_v3:
1261         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1262                  data->version);
1263         return -EINVAL;
1264
1265 out_no_sec:
1266         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1267         return -EINVAL;
1268
1269 #ifndef CONFIG_NFS_V3
1270 out_v3_not_compiled:
1271         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1272         return -EPROTONOSUPPORT;
1273 #endif /* !CONFIG_NFS_V3 */
1274
1275 out_no_address:
1276         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1277         return -EINVAL;
1278
1279 out_invalid_fh:
1280         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1281         return -EINVAL;
1282 }
1283
1284 /*
1285  * Initialise the common bits of the superblock
1286  */
1287 static inline void nfs_initialise_sb(struct super_block *sb)
1288 {
1289         struct nfs_server *server = NFS_SB(sb);
1290
1291         sb->s_magic = NFS_SUPER_MAGIC;
1292
1293         /* We probably want something more informative here */
1294         snprintf(sb->s_id, sizeof(sb->s_id),
1295                  "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
1296
1297         if (sb->s_blocksize == 0)
1298                 sb->s_blocksize = nfs_block_bits(server->wsize,
1299                                                  &sb->s_blocksize_bits);
1300
1301         if (server->flags & NFS_MOUNT_NOAC)
1302                 sb->s_flags |= MS_SYNCHRONOUS;
1303
1304         nfs_super_set_maxbytes(sb, server->maxfilesize);
1305 }
1306
1307 /*
1308  * Finish setting up an NFS2/3 superblock
1309  */
1310 static void nfs_fill_super(struct super_block *sb,
1311                            struct nfs_parsed_mount_data *data)
1312 {
1313         struct nfs_server *server = NFS_SB(sb);
1314
1315         sb->s_blocksize_bits = 0;
1316         sb->s_blocksize = 0;
1317         if (data->bsize)
1318                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
1319
1320         if (server->flags & NFS_MOUNT_VER3) {
1321                 /* The VFS shouldn't apply the umask to mode bits. We will do
1322                  * so ourselves when necessary.
1323                  */
1324                 sb->s_flags |= MS_POSIXACL;
1325                 sb->s_time_gran = 1;
1326         }
1327
1328         sb->s_op = &nfs_sops;
1329         nfs_initialise_sb(sb);
1330 }
1331
1332 /*
1333  * Finish setting up a cloned NFS2/3 superblock
1334  */
1335 static void nfs_clone_super(struct super_block *sb,
1336                             const struct super_block *old_sb)
1337 {
1338         struct nfs_server *server = NFS_SB(sb);
1339
1340         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1341         sb->s_blocksize = old_sb->s_blocksize;
1342         sb->s_maxbytes = old_sb->s_maxbytes;
1343
1344         if (server->flags & NFS_MOUNT_VER3) {
1345                 /* The VFS shouldn't apply the umask to mode bits. We will do
1346                  * so ourselves when necessary.
1347                  */
1348                 sb->s_flags |= MS_POSIXACL;
1349                 sb->s_time_gran = 1;
1350         }
1351
1352         sb->s_op = old_sb->s_op;
1353         nfs_initialise_sb(sb);
1354 }
1355
1356 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
1357
1358 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
1359 {
1360         const struct nfs_server *a = s->s_fs_info;
1361         const struct rpc_clnt *clnt_a = a->client;
1362         const struct rpc_clnt *clnt_b = b->client;
1363
1364         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
1365                 goto Ebusy;
1366         if (a->nfs_client != b->nfs_client)
1367                 goto Ebusy;
1368         if (a->flags != b->flags)
1369                 goto Ebusy;
1370         if (a->wsize != b->wsize)
1371                 goto Ebusy;
1372         if (a->rsize != b->rsize)
1373                 goto Ebusy;
1374         if (a->acregmin != b->acregmin)
1375                 goto Ebusy;
1376         if (a->acregmax != b->acregmax)
1377                 goto Ebusy;
1378         if (a->acdirmin != b->acdirmin)
1379                 goto Ebusy;
1380         if (a->acdirmax != b->acdirmax)
1381                 goto Ebusy;
1382         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
1383                 goto Ebusy;
1384         return 1;
1385 Ebusy:
1386         return 0;
1387 }
1388
1389 struct nfs_sb_mountdata {
1390         struct nfs_server *server;
1391         int mntflags;
1392 };
1393
1394 static int nfs_set_super(struct super_block *s, void *data)
1395 {
1396         struct nfs_sb_mountdata *sb_mntdata = data;
1397         struct nfs_server *server = sb_mntdata->server;
1398         int ret;
1399
1400         s->s_flags = sb_mntdata->mntflags;
1401         s->s_fs_info = server;
1402         ret = set_anon_super(s, server);
1403         if (ret == 0)
1404                 server->s_dev = s->s_dev;
1405         return ret;
1406 }
1407
1408 static int nfs_compare_super_address(struct nfs_server *server1,
1409                                      struct nfs_server *server2)
1410 {
1411         struct sockaddr *sap1, *sap2;
1412
1413         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
1414         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
1415
1416         if (sap1->sa_family != sap2->sa_family)
1417                 return 0;
1418
1419         switch (sap1->sa_family) {
1420         case AF_INET: {
1421                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
1422                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
1423                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
1424                         return 0;
1425                 if (sin1->sin_port != sin2->sin_port)
1426                         return 0;
1427                 break;
1428         }
1429         case AF_INET6: {
1430                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
1431                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
1432                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
1433                         return 0;
1434                 if (sin1->sin6_port != sin2->sin6_port)
1435                         return 0;
1436                 break;
1437         }
1438         default:
1439                 return 0;
1440         }
1441
1442         return 1;
1443 }
1444
1445 static int nfs_compare_super(struct super_block *sb, void *data)
1446 {
1447         struct nfs_sb_mountdata *sb_mntdata = data;
1448         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
1449         int mntflags = sb_mntdata->mntflags;
1450
1451         if (!nfs_compare_super_address(old, server))
1452                 return 0;
1453         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
1454         if (old->flags & NFS_MOUNT_UNSHARED)
1455                 return 0;
1456         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
1457                 return 0;
1458         return nfs_compare_mount_options(sb, server, mntflags);
1459 }
1460
1461 static int nfs_get_sb(struct file_system_type *fs_type,
1462         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1463 {
1464         struct nfs_server *server = NULL;
1465         struct super_block *s;
1466         struct nfs_fh mntfh;
1467         struct nfs_parsed_mount_data data;
1468         struct dentry *mntroot;
1469         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1470         struct nfs_sb_mountdata sb_mntdata = {
1471                 .mntflags = flags,
1472         };
1473         int error;
1474
1475         /* Validate the mount data */
1476         error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);
1477         if (error < 0)
1478                 goto out;
1479
1480         /* Get a volume representation */
1481         server = nfs_create_server(&data, &mntfh);
1482         if (IS_ERR(server)) {
1483                 error = PTR_ERR(server);
1484                 goto out;
1485         }
1486         sb_mntdata.server = server;
1487
1488         if (server->flags & NFS_MOUNT_UNSHARED)
1489                 compare_super = NULL;
1490
1491         /* Get a superblock - note that we may end up sharing one that already exists */
1492         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1493         if (IS_ERR(s)) {
1494                 error = PTR_ERR(s);
1495                 goto out_err_nosb;
1496         }
1497
1498         if (s->s_fs_info != server) {
1499                 nfs_free_server(server);
1500                 server = NULL;
1501         }
1502
1503         if (!s->s_root) {
1504                 /* initial superblock/root creation */
1505                 nfs_fill_super(s, &data);
1506         }
1507
1508         mntroot = nfs_get_root(s, &mntfh);
1509         if (IS_ERR(mntroot)) {
1510                 error = PTR_ERR(mntroot);
1511                 goto error_splat_super;
1512         }
1513
1514         s->s_flags |= MS_ACTIVE;
1515         mnt->mnt_sb = s;
1516         mnt->mnt_root = mntroot;
1517         error = 0;
1518
1519 out:
1520         kfree(data.nfs_server.hostname);
1521         kfree(data.mount_server.hostname);
1522         return error;
1523
1524 out_err_nosb:
1525         nfs_free_server(server);
1526         goto out;
1527
1528 error_splat_super:
1529         up_write(&s->s_umount);
1530         deactivate_super(s);
1531         goto out;
1532 }
1533
1534 /*
1535  * Destroy an NFS2/3 superblock
1536  */
1537 static void nfs_kill_super(struct super_block *s)
1538 {
1539         struct nfs_server *server = NFS_SB(s);
1540
1541         kill_anon_super(s);
1542         nfs_free_server(server);
1543 }
1544
1545 /*
1546  * Clone an NFS2/3 server record on xdev traversal (FSID-change)
1547  */
1548 static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
1549                            const char *dev_name, void *raw_data,
1550                            struct vfsmount *mnt)
1551 {
1552         struct nfs_clone_mount *data = raw_data;
1553         struct super_block *s;
1554         struct nfs_server *server;
1555         struct dentry *mntroot;
1556         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1557         struct nfs_sb_mountdata sb_mntdata = {
1558                 .mntflags = flags,
1559         };
1560         int error;
1561
1562         dprintk("--> nfs_xdev_get_sb()\n");
1563
1564         /* create a new volume representation */
1565         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1566         if (IS_ERR(server)) {
1567                 error = PTR_ERR(server);
1568                 goto out_err_noserver;
1569         }
1570         sb_mntdata.server = server;
1571
1572         if (server->flags & NFS_MOUNT_UNSHARED)
1573                 compare_super = NULL;
1574
1575         /* Get a superblock - note that we may end up sharing one that already exists */
1576         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1577         if (IS_ERR(s)) {
1578                 error = PTR_ERR(s);
1579                 goto out_err_nosb;
1580         }
1581
1582         if (s->s_fs_info != server) {
1583                 nfs_free_server(server);
1584                 server = NULL;
1585         }
1586
1587         if (!s->s_root) {
1588                 /* initial superblock/root creation */
1589                 nfs_clone_super(s, data->sb);
1590         }
1591
1592         mntroot = nfs_get_root(s, data->fh);
1593         if (IS_ERR(mntroot)) {
1594                 error = PTR_ERR(mntroot);
1595                 goto error_splat_super;
1596         }
1597         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1598                 dput(mntroot);
1599                 error = -ESTALE;
1600                 goto error_splat_super;
1601         }
1602
1603         s->s_flags |= MS_ACTIVE;
1604         mnt->mnt_sb = s;
1605         mnt->mnt_root = mntroot;
1606
1607         dprintk("<-- nfs_xdev_get_sb() = 0\n");
1608         return 0;
1609
1610 out_err_nosb:
1611         nfs_free_server(server);
1612 out_err_noserver:
1613         dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
1614         return error;
1615
1616 error_splat_super:
1617         up_write(&s->s_umount);
1618         deactivate_super(s);
1619         dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
1620         return error;
1621 }
1622
1623 #ifdef CONFIG_NFS_V4
1624
1625 /*
1626  * Finish setting up a cloned NFS4 superblock
1627  */
1628 static void nfs4_clone_super(struct super_block *sb,
1629                             const struct super_block *old_sb)
1630 {
1631         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
1632         sb->s_blocksize = old_sb->s_blocksize;
1633         sb->s_maxbytes = old_sb->s_maxbytes;
1634         sb->s_time_gran = 1;
1635         sb->s_op = old_sb->s_op;
1636         nfs_initialise_sb(sb);
1637 }
1638
1639 /*
1640  * Set up an NFS4 superblock
1641  */
1642 static void nfs4_fill_super(struct super_block *sb)
1643 {
1644         sb->s_time_gran = 1;
1645         sb->s_op = &nfs4_sops;
1646         nfs_initialise_sb(sb);
1647 }
1648
1649 /*
1650  * If the user didn't specify a port, set the port number to
1651  * the NFS version 4 default port.
1652  */
1653 static void nfs4_default_port(struct sockaddr *sap)
1654 {
1655         switch (sap->sa_family) {
1656         case AF_INET: {
1657                 struct sockaddr_in *ap = (struct sockaddr_in *)sap;
1658                 if (ap->sin_port == 0)
1659                         ap->sin_port = htons(NFS_PORT);
1660                 break;
1661         }
1662         case AF_INET6: {
1663                 struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
1664                 if (ap->sin6_port == 0)
1665                         ap->sin6_port = htons(NFS_PORT);
1666                 break;
1667         }
1668         }
1669 }
1670
1671 /*
1672  * Validate NFSv4 mount options
1673  */
1674 static int nfs4_validate_mount_data(void *options,
1675                                     struct nfs_parsed_mount_data *args,
1676                                     const char *dev_name)
1677 {
1678         struct sockaddr_in *ap;
1679         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
1680         char *c;
1681
1682         memset(args, 0, sizeof(*args));
1683
1684         if (data == NULL)
1685                 goto out_no_data;
1686
1687         args->rsize             = NFS_MAX_FILE_IO_SIZE;
1688         args->wsize             = NFS_MAX_FILE_IO_SIZE;
1689         args->timeo             = 600;
1690         args->retrans           = 2;
1691         args->acregmin          = 3;
1692         args->acregmax          = 60;
1693         args->acdirmin          = 30;
1694         args->acdirmax          = 60;
1695         args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1696
1697         switch (data->version) {
1698         case 1:
1699                 ap = (struct sockaddr_in *)&args->nfs_server.address;
1700                 if (data->host_addrlen > sizeof(args->nfs_server.address))
1701                         goto out_no_address;
1702                 if (data->host_addrlen == 0)
1703                         goto out_no_address;
1704                 args->nfs_server.addrlen = data->host_addrlen;
1705                 if (copy_from_user(ap, data->host_addr, data->host_addrlen))
1706                         return -EFAULT;
1707                 if (!nfs_verify_server_address((struct sockaddr *)
1708                                                 &args->nfs_server.address))
1709                         goto out_no_address;
1710
1711                 nfs4_default_port((struct sockaddr *)
1712                                   &args->nfs_server.address);
1713
1714                 switch (data->auth_flavourlen) {
1715                 case 0:
1716                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1717                         break;
1718                 case 1:
1719                         if (copy_from_user(&args->auth_flavors[0],
1720                                            data->auth_flavours,
1721                                            sizeof(args->auth_flavors[0])))
1722                                 return -EFAULT;
1723                         break;
1724                 default:
1725                         goto out_inval_auth;
1726                 }
1727
1728                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1729                 if (IS_ERR(c))
1730                         return PTR_ERR(c);
1731                 args->nfs_server.hostname = c;
1732
1733                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1734                 if (IS_ERR(c))
1735                         return PTR_ERR(c);
1736                 args->nfs_server.export_path = c;
1737                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1738
1739                 c = strndup_user(data->client_addr.data, 16);
1740                 if (IS_ERR(c))
1741                         return PTR_ERR(c);
1742                 args->client_address = c;
1743
1744                 /*
1745                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
1746                  * can deal with.
1747                  */
1748
1749                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
1750                 args->rsize     = data->rsize;
1751                 args->wsize     = data->wsize;
1752                 args->timeo     = data->timeo;
1753                 args->retrans   = data->retrans;
1754                 args->acregmin  = data->acregmin;
1755                 args->acregmax  = data->acregmax;
1756                 args->acdirmin  = data->acdirmin;
1757                 args->acdirmax  = data->acdirmax;
1758                 args->nfs_server.protocol = data->proto;
1759
1760                 break;
1761         default: {
1762                 unsigned int len;
1763
1764                 if (nfs_parse_mount_options((char *)options, args) == 0)
1765                         return -EINVAL;
1766
1767                 if (!nfs_verify_server_address((struct sockaddr *)
1768                                                 &args->nfs_server.address))
1769                         return -EINVAL;
1770
1771                 nfs4_default_port((struct sockaddr *)
1772                                   &args->nfs_server.address);
1773
1774                 switch (args->auth_flavor_len) {
1775                 case 0:
1776                         args->auth_flavors[0] = RPC_AUTH_UNIX;
1777                         break;
1778                 case 1:
1779                         break;
1780                 default:
1781                         goto out_inval_auth;
1782                 }
1783
1784                 /*
1785                  * Split "dev_name" into "hostname:mntpath".
1786                  */
1787                 c = strchr(dev_name, ':');
1788                 if (c == NULL)
1789                         return -EINVAL;
1790                 /* while calculating len, pretend ':' is '\0' */
1791                 len = c - dev_name;
1792                 if (len > NFS4_MAXNAMLEN)
1793                         return -ENAMETOOLONG;
1794                 /* N.B. caller will free nfs_server.hostname in all cases */
1795                 args->nfs_server.hostname = kstrndup(dev_name, len, GFP_KERNEL);
1796
1797                 c++;                    /* step over the ':' */
1798                 len = strlen(c);
1799                 if (len > NFS4_MAXPATHLEN)
1800                         return -ENAMETOOLONG;
1801                 args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
1802
1803                 dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);
1804
1805                 if (args->client_address == NULL)
1806                         goto out_no_client_address;
1807
1808                 break;
1809                 }
1810         }
1811
1812         return 0;
1813
1814 out_no_data:
1815         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
1816         return -EINVAL;
1817
1818 out_inval_auth:
1819         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
1820                  data->auth_flavourlen);
1821         return -EINVAL;
1822
1823 out_no_address:
1824         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
1825         return -EINVAL;
1826
1827 out_no_client_address:
1828         dfprintk(MOUNT, "NFS4: mount program didn't pass callback address\n");
1829         return -EINVAL;
1830 }
1831
1832 /*
1833  * Get the superblock for an NFS4 mountpoint
1834  */
1835 static int nfs4_get_sb(struct file_system_type *fs_type,
1836         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
1837 {
1838         struct nfs_parsed_mount_data data;
1839         struct super_block *s;
1840         struct nfs_server *server;
1841         struct nfs_fh mntfh;
1842         struct dentry *mntroot;
1843         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1844         struct nfs_sb_mountdata sb_mntdata = {
1845                 .mntflags = flags,
1846         };
1847         int error;
1848
1849         /* Validate the mount data */
1850         error = nfs4_validate_mount_data(raw_data, &data, dev_name);
1851         if (error < 0)
1852                 goto out;
1853
1854         /* Get a volume representation */
1855         server = nfs4_create_server(&data, &mntfh);
1856         if (IS_ERR(server)) {
1857                 error = PTR_ERR(server);
1858                 goto out;
1859         }
1860         sb_mntdata.server = server;
1861
1862         if (server->flags & NFS4_MOUNT_UNSHARED)
1863                 compare_super = NULL;
1864
1865         /* Get a superblock - note that we may end up sharing one that already exists */
1866         s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
1867         if (IS_ERR(s)) {
1868                 error = PTR_ERR(s);
1869                 goto out_free;
1870         }
1871
1872         if (s->s_fs_info != server) {
1873                 nfs_free_server(server);
1874                 server = NULL;
1875         }
1876
1877         if (!s->s_root) {
1878                 /* initial superblock/root creation */
1879                 nfs4_fill_super(s);
1880         }
1881
1882         mntroot = nfs4_get_root(s, &mntfh);
1883         if (IS_ERR(mntroot)) {
1884                 error = PTR_ERR(mntroot);
1885                 goto error_splat_super;
1886         }
1887
1888         s->s_flags |= MS_ACTIVE;
1889         mnt->mnt_sb = s;
1890         mnt->mnt_root = mntroot;
1891         error = 0;
1892
1893 out:
1894         kfree(data.client_address);
1895         kfree(data.nfs_server.export_path);
1896         kfree(data.nfs_server.hostname);
1897         return error;
1898
1899 out_free:
1900         nfs_free_server(server);
1901         goto out;
1902
1903 error_splat_super:
1904         up_write(&s->s_umount);
1905         deactivate_super(s);
1906         goto out;
1907 }
1908
1909 static void nfs4_kill_super(struct super_block *sb)
1910 {
1911         struct nfs_server *server = NFS_SB(sb);
1912
1913         nfs_return_all_delegations(sb);
1914         kill_anon_super(sb);
1915
1916         nfs4_renewd_prepare_shutdown(server);
1917         nfs_free_server(server);
1918 }
1919
1920 /*
1921  * Clone an NFS4 server record on xdev traversal (FSID-change)
1922  */
1923 static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
1924                             const char *dev_name, void *raw_data,
1925                             struct vfsmount *mnt)
1926 {
1927         struct nfs_clone_mount *data = raw_data;
1928         struct super_block *s;
1929         struct nfs_server *server;
1930         struct dentry *mntroot;
1931         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
1932         struct nfs_sb_mountdata sb_mntdata = {
1933                 .mntflags = flags,
1934         };
1935         int error;
1936
1937         dprintk("--> nfs4_xdev_get_sb()\n");
1938
1939         /* create a new volume representation */
1940         server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
1941         if (IS_ERR(server)) {
1942                 error = PTR_ERR(server);
1943                 goto out_err_noserver;
1944         }
1945         sb_mntdata.server = server;
1946
1947         if (server->flags & NFS4_MOUNT_UNSHARED)
1948                 compare_super = NULL;
1949
1950         /* Get a superblock - note that we may end up sharing one that already exists */
1951         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
1952         if (IS_ERR(s)) {
1953                 error = PTR_ERR(s);
1954                 goto out_err_nosb;
1955         }
1956
1957         if (s->s_fs_info != server) {
1958                 nfs_free_server(server);
1959                 server = NULL;
1960         }
1961
1962         if (!s->s_root) {
1963                 /* initial superblock/root creation */
1964                 nfs4_clone_super(s, data->sb);
1965         }
1966
1967         mntroot = nfs4_get_root(s, data->fh);
1968         if (IS_ERR(mntroot)) {
1969                 error = PTR_ERR(mntroot);
1970                 goto error_splat_super;
1971         }
1972         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
1973                 dput(mntroot);
1974                 error = -ESTALE;
1975                 goto error_splat_super;
1976         }
1977
1978         s->s_flags |= MS_ACTIVE;
1979         mnt->mnt_sb = s;
1980         mnt->mnt_root = mntroot;
1981
1982         dprintk("<-- nfs4_xdev_get_sb() = 0\n");
1983         return 0;
1984
1985 out_err_nosb:
1986         nfs_free_server(server);
1987 out_err_noserver:
1988         dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
1989         return error;
1990
1991 error_splat_super:
1992         up_write(&s->s_umount);
1993         deactivate_super(s);
1994         dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
1995         return error;
1996 }
1997
1998 /*
1999  * Create an NFS4 server record on referral traversal
2000  */
2001 static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
2002                                 const char *dev_name, void *raw_data,
2003                                 struct vfsmount *mnt)
2004 {
2005         struct nfs_clone_mount *data = raw_data;
2006         struct super_block *s;
2007         struct nfs_server *server;
2008         struct dentry *mntroot;
2009         struct nfs_fh mntfh;
2010         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2011         struct nfs_sb_mountdata sb_mntdata = {
2012                 .mntflags = flags,
2013         };
2014         int error;
2015
2016         dprintk("--> nfs4_referral_get_sb()\n");
2017
2018         /* create a new volume representation */
2019         server = nfs4_create_referral_server(data, &mntfh);
2020         if (IS_ERR(server)) {
2021                 error = PTR_ERR(server);
2022                 goto out_err_noserver;
2023         }
2024         sb_mntdata.server = server;
2025
2026         if (server->flags & NFS4_MOUNT_UNSHARED)
2027                 compare_super = NULL;
2028
2029         /* Get a superblock - note that we may end up sharing one that already exists */
2030         s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
2031         if (IS_ERR(s)) {
2032                 error = PTR_ERR(s);
2033                 goto out_err_nosb;
2034         }
2035
2036         if (s->s_fs_info != server) {
2037                 nfs_free_server(server);
2038                 server = NULL;
2039         }
2040
2041         if (!s->s_root) {
2042                 /* initial superblock/root creation */
2043                 nfs4_fill_super(s);
2044         }
2045
2046         mntroot = nfs4_get_root(s, &mntfh);
2047         if (IS_ERR(mntroot)) {
2048                 error = PTR_ERR(mntroot);
2049                 goto error_splat_super;
2050         }
2051         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
2052                 dput(mntroot);
2053                 error = -ESTALE;
2054                 goto error_splat_super;
2055         }
2056
2057         s->s_flags |= MS_ACTIVE;
2058         mnt->mnt_sb = s;
2059         mnt->mnt_root = mntroot;
2060
2061         dprintk("<-- nfs4_referral_get_sb() = 0\n");
2062         return 0;
2063
2064 out_err_nosb:
2065         nfs_free_server(server);
2066 out_err_noserver:
2067         dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
2068         return error;
2069
2070 error_splat_super:
2071         up_write(&s->s_umount);
2072         deactivate_super(s);
2073         dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
2074         return error;
2075 }
2076
2077 #endif /* CONFIG_NFS_V4 */