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