fs/nfsd/nfsctl.c

   1 /*
   2  * Syscall interface to knfsd.
   3  *
   4  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   5  */
   6
   7 #include <linux/slab.h>
   8 #include <linux/namei.h>
   9 #include <linux/ctype.h>
  10
  11 #include <linux/sunrpc/svcsock.h>
  12 #include <linux/nfsd/syscall.h>
  13 #include <linux/lockd/lockd.h>
  14 #include <linux/sunrpc/clnt.h>
  15 #include <linux/sunrpc/gss_api.h>
  16
  17 #include "idmap.h"
  18 #include "nfsd.h"
  19 #include "cache.h"
  20
  21 /*
  22  *      We have a single directory with several nodes in it.
  23  */
  24 enum {
  25         NFSD_Root = 1,
  26 #ifdef CONFIG_NFSD_DEPRECATED
  27         NFSD_Svc,
  28         NFSD_Add,
  29         NFSD_Del,
  30         NFSD_Export,
  31         NFSD_Unexport,
  32         NFSD_Getfd,
  33         NFSD_Getfs,
  34 #endif
  35         NFSD_List,
  36         NFSD_Export_features,
  37         NFSD_Fh,
  38         NFSD_FO_UnlockIP,
  39         NFSD_FO_UnlockFS,
  40         NFSD_Threads,
  41         NFSD_Pool_Threads,
  42         NFSD_Pool_Stats,
  43         NFSD_Versions,
  44         NFSD_Ports,
  45         NFSD_MaxBlkSize,
  46         NFSD_SupportedEnctypes,
  47         /*
  48          * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
  49          * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
  50          */
  51 #ifdef CONFIG_NFSD_V4
  52         NFSD_Leasetime,
  53         NFSD_Gracetime,
  54         NFSD_RecoveryDir,
  55 #endif
  56 };
  57
  58 /*
  59  * write() for these nodes.
  60  */
  61 #ifdef CONFIG_NFSD_DEPRECATED
  62 static ssize_t write_svc(struct file *file, char *buf, size_t size);
  63 static ssize_t write_add(struct file *file, char *buf, size_t size);
  64 static ssize_t write_del(struct file *file, char *buf, size_t size);
  65 static ssize_t write_export(struct file *file, char *buf, size_t size);
  66 static ssize_t write_unexport(struct file *file, char *buf, size_t size);
  67 static ssize_t write_getfd(struct file *file, char *buf, size_t size);
  68 static ssize_t write_getfs(struct file *file, char *buf, size_t size);
  69 #endif
  70 static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
  71 static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size);
  72 static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size);
  73 static ssize_t write_threads(struct file *file, char *buf, size_t size);
  74 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
  75 static ssize_t write_versions(struct file *file, char *buf, size_t size);
  76 static ssize_t write_ports(struct file *file, char *buf, size_t size);
  77 static ssize_t write_maxblksize(struct file *file, char *buf, size_t size);
  78 #ifdef CONFIG_NFSD_V4
  79 static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
  80 static ssize_t write_gracetime(struct file *file, char *buf, size_t size);
  81 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
  82 #endif
  83
  84 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
  85 #ifdef CONFIG_NFSD_DEPRECATED
  86         [NFSD_Svc] = write_svc,
  87         [NFSD_Add] = write_add,
  88         [NFSD_Del] = write_del,
  89         [NFSD_Export] = write_export,
  90         [NFSD_Unexport] = write_unexport,
  91         [NFSD_Getfd] = write_getfd,
  92         [NFSD_Getfs] = write_getfs,
  93 #endif
  94         [NFSD_Fh] = write_filehandle,
  95         [NFSD_FO_UnlockIP] = write_unlock_ip,
  96         [NFSD_FO_UnlockFS] = write_unlock_fs,
  97         [NFSD_Threads] = write_threads,
  98         [NFSD_Pool_Threads] = write_pool_threads,
  99         [NFSD_Versions] = write_versions,
 100         [NFSD_Ports] = write_ports,
 101         [NFSD_MaxBlkSize] = write_maxblksize,
 102 #ifdef CONFIG_NFSD_V4
 103         [NFSD_Leasetime] = write_leasetime,
 104         [NFSD_Gracetime] = write_gracetime,
 105         [NFSD_RecoveryDir] = write_recoverydir,
 106 #endif
 107 };
 108
 109 static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 110 {
 111         ino_t ino =  file->f_path.dentry->d_inode->i_ino;
 112         char *data;
 113         ssize_t rv;
 114
 115         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 116                 return -EINVAL;
 117
 118         data = simple_transaction_get(file, buf, size);
 119         if (IS_ERR(data))
 120                 return PTR_ERR(data);
 121
 122         rv =  write_op[ino](file, data, size);
 123         if (rv >= 0) {
 124                 simple_transaction_set(file, rv);
 125                 rv = size;
 126         }
 127         return rv;
 128 }
 129
 130 static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
 131 {
 132 #ifdef CONFIG_NFSD_DEPRECATED
 133         static int warned;
 134         if (file->f_dentry->d_name.name[0] == '.' && !warned) {
 135                 printk(KERN_INFO
 136                        "Warning: \"%s\" uses deprecated NFSD interface: %s."
 137                        "  This will be removed in 2.6.40\n",
 138                        current->comm, file->f_dentry->d_name.name);
 139                 warned = 1;
 140         }
 141 #endif
 142         if (! file->private_data) {
 143                 /* An attempt to read a transaction file without writing
 144                  * causes a 0-byte write so that the file can return
 145                  * state information
 146                  */
 147                 ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
 148                 if (rv < 0)
 149                         return rv;
 150         }
 151         return simple_transaction_read(file, buf, size, pos);
 152 }
 153
 154 static const struct file_operations transaction_ops = {
 155         .write          = nfsctl_transaction_write,
 156         .read           = nfsctl_transaction_read,
 157         .release        = simple_transaction_release,
 158         .llseek         = default_llseek,
 159 };
 160
 161 static int exports_open(struct inode *inode, struct file *file)
 162 {
 163         return seq_open(file, &nfs_exports_op);
 164 }
 165
 166 static const struct file_operations exports_operations = {
 167         .open           = exports_open,
 168         .read           = seq_read,
 169         .llseek         = seq_lseek,
 170         .release        = seq_release,
 171         .owner          = THIS_MODULE,
 172 };
 173
 174 static int export_features_show(struct seq_file *m, void *v)
 175 {
 176         seq_printf(m, "0x%x 0x%x\n", NFSEXP_ALLFLAGS, NFSEXP_SECINFO_FLAGS);
 177         return 0;
 178 }
 179
 180 static int export_features_open(struct inode *inode, struct file *file)
 181 {
 182         return single_open(file, export_features_show, NULL);
 183 }
 184
 185 static struct file_operations export_features_operations = {
 186         .open           = export_features_open,
 187         .read           = seq_read,
 188         .llseek         = seq_lseek,
 189         .release        = single_release,
 190 };
 191
 192 static int supported_enctypes_show(struct seq_file *m, void *v)
 193 {
 194         struct gss_api_mech *k5mech;
 195
 196         k5mech = gss_mech_get_by_name("krb5");
 197         if (k5mech == NULL)
 198                 goto out;
 199         if (k5mech->gm_upcall_enctypes != NULL)
 200                 seq_printf(m, k5mech->gm_upcall_enctypes);
 201         gss_mech_put(k5mech);
 202 out:
 203         return 0;
 204 }
 205
 206 static int supported_enctypes_open(struct inode *inode, struct file *file)
 207 {
 208         return single_open(file, supported_enctypes_show, NULL);
 209 }
 210
 211 static struct file_operations supported_enctypes_ops = {
 212         .open           = supported_enctypes_open,
 213         .read           = seq_read,
 214         .llseek         = seq_lseek,
 215         .release        = single_release,
 216 };
 217
 218 extern int nfsd_pool_stats_open(struct inode *inode, struct file *file);
 219 extern int nfsd_pool_stats_release(struct inode *inode, struct file *file);
 220
 221 static const struct file_operations pool_stats_operations = {
 222         .open           = nfsd_pool_stats_open,
 223         .read           = seq_read,
 224         .llseek         = seq_lseek,
 225         .release        = nfsd_pool_stats_release,
 226         .owner          = THIS_MODULE,
 227 };
 228
 229 /*----------------------------------------------------------------------------*/
 230 /*
 231  * payload - write methods
 232  */
 233
 234 #ifdef CONFIG_NFSD_DEPRECATED
 235 /**
 236  * write_svc - Start kernel's NFSD server
 237  *
 238  * Deprecated.  /proc/fs/nfsd/threads is preferred.
 239  * Function remains to support old versions of nfs-utils.
 240  *
 241  * Input:
 242  *                      buf:    struct nfsctl_svc
 243  *                              svc_port:       port number of this
 244  *                                              server's listener
 245  *                              svc_nthreads:   number of threads to start
 246  *                      size:   size in bytes of passed in nfsctl_svc
 247  * Output:
 248  *      On success:     returns zero
 249  *      On error:       return code is negative errno value
 250  */
 251 static ssize_t write_svc(struct file *file, char *buf, size_t size)
 252 {
 253         struct nfsctl_svc *data;
 254         int err;
 255         if (size < sizeof(*data))
 256                 return -EINVAL;
 257         data = (struct nfsctl_svc*) buf;
 258         err = nfsd_svc(data->svc_port, data->svc_nthreads);
 259         if (err < 0)
 260                 return err;
 261         return 0;
 262 }
 263
 264 /**
 265  * write_add - Add or modify client entry in auth unix cache
 266  *
 267  * Deprecated.  /proc/net/rpc/auth.unix.ip is preferred.
 268  * Function remains to support old versions of nfs-utils.
 269  *
 270  * Input:
 271  *                      buf:    struct nfsctl_client
 272  *                              cl_ident:       '\0'-terminated C string
 273  *                                              containing domain name
 274  *                                              of client
 275  *                              cl_naddr:       no. of items in cl_addrlist
 276  *                              cl_addrlist:    array of client addresses
 277  *                              cl_fhkeytype:   ignored
 278  *                              cl_fhkeylen:    ignored
 279  *                              cl_fhkey:       ignored
 280  *                      size:   size in bytes of passed in nfsctl_client
 281  * Output:
 282  *      On success:     returns zero
 283  *      On error:       return code is negative errno value
 284  *
 285  * Note: Only AF_INET client addresses are passed in, since
 286  * nfsctl_client.cl_addrlist contains only in_addr fields for addresses.
 287  */
 288 static ssize_t write_add(struct file *file, char *buf, size_t size)
 289 {
 290         struct nfsctl_client *data;
 291         if (size < sizeof(*data))
 292                 return -EINVAL;
 293         data = (struct nfsctl_client *)buf;
 294         return exp_addclient(data);
 295 }
 296
 297 /**
 298  * write_del - Remove client from auth unix cache
 299  *
 300  * Deprecated.  /proc/net/rpc/auth.unix.ip is preferred.
 301  * Function remains to support old versions of nfs-utils.
 302  *
 303  * Input:
 304  *                      buf:    struct nfsctl_client
 305  *                              cl_ident:       '\0'-terminated C string
 306  *                                              containing domain name
 307  *                                              of client
 308  *                              cl_naddr:       ignored
 309  *                              cl_addrlist:    ignored
 310  *                              cl_fhkeytype:   ignored
 311  *                              cl_fhkeylen:    ignored
 312  *                              cl_fhkey:       ignored
 313  *                      size:   size in bytes of passed in nfsctl_client
 314  * Output:
 315  *      On success:     returns zero
 316  *      On error:       return code is negative errno value
 317  *
 318  * Note: Only AF_INET client addresses are passed in, since
 319  * nfsctl_client.cl_addrlist contains only in_addr fields for addresses.
 320  */
 321 static ssize_t write_del(struct file *file, char *buf, size_t size)
 322 {
 323         struct nfsctl_client *data;
 324         if (size < sizeof(*data))
 325                 return -EINVAL;
 326         data = (struct nfsctl_client *)buf;
 327         return exp_delclient(data);
 328 }
 329
 330 /**
 331  * write_export - Export part or all of a local file system
 332  *
 333  * Deprecated.  /proc/net/rpc/{nfsd.export,nfsd.fh} are preferred.
 334  * Function remains to support old versions of nfs-utils.
 335  *
 336  * Input:
 337  *                      buf:    struct nfsctl_export
 338  *                              ex_client:      '\0'-terminated C string
 339  *                                              containing domain name
 340  *                                              of client allowed to access
 341  *                                              this export
 342  *                              ex_path:        '\0'-terminated C string
 343  *                                              containing pathname of
 344  *                                              directory in local file system
 345  *                              ex_dev:         fsid to use for this export
 346  *                              ex_ino:         ignored
 347  *                              ex_flags:       export flags for this export
 348  *                              ex_anon_uid:    UID to use for anonymous
 349  *                                              requests
 350  *                              ex_anon_gid:    GID to use for anonymous
 351  *                                              requests
 352  *                      size:   size in bytes of passed in nfsctl_export
 353  * Output:
 354  *      On success:     returns zero
 355  *      On error:       return code is negative errno value
 356  */
 357 static ssize_t write_export(struct file *file, char *buf, size_t size)
 358 {
 359         struct nfsctl_export *data;
 360         if (size < sizeof(*data))
 361                 return -EINVAL;
 362         data = (struct nfsctl_export*)buf;
 363         return exp_export(data);
 364 }
 365
 366 /**
 367  * write_unexport - Unexport a previously exported file system
 368  *
 369  * Deprecated.  /proc/net/rpc/{nfsd.export,nfsd.fh} are preferred.
 370  * Function remains to support old versions of nfs-utils.
 371  *
 372  * Input:
 373  *                      buf:    struct nfsctl_export
 374  *                              ex_client:      '\0'-terminated C string
 375  *                                              containing domain name
 376  *                                              of client no longer allowed
 377  *                                              to access this export
 378  *                              ex_path:        '\0'-terminated C string
 379  *                                              containing pathname of
 380  *                                              directory in local file system
 381  *                              ex_dev:         ignored
 382  *                              ex_ino:         ignored
 383  *                              ex_flags:       ignored
 384  *                              ex_anon_uid:    ignored
 385  *                              ex_anon_gid:    ignored
 386  *                      size:   size in bytes of passed in nfsctl_export
 387  * Output:
 388  *      On success:     returns zero
 389  *      On error:       return code is negative errno value
 390  */
 391 static ssize_t write_unexport(struct file *file, char *buf, size_t size)
 392 {
 393         struct nfsctl_export *data;
 394
 395         if (size < sizeof(*data))
 396                 return -EINVAL;
 397         data = (struct nfsctl_export*)buf;
 398         return exp_unexport(data);
 399 }
 400
 401 /**
 402  * write_getfs - Get a variable-length NFS file handle by path
 403  *
 404  * Deprecated.  /proc/fs/nfsd/filehandle is preferred.
 405  * Function remains to support old versions of nfs-utils.
 406  *
 407  * Input:
 408  *                      buf:    struct nfsctl_fsparm
 409  *                              gd_addr:        socket address of client
 410  *                              gd_path:        '\0'-terminated C string
 411  *                                              containing pathname of
 412  *                                              directory in local file system
 413  *                              gd_maxlen:      maximum size of returned file
 414  *                                              handle
 415  *                      size:   size in bytes of passed in nfsctl_fsparm
 416  * Output:
 417  *      On success:     passed-in buffer filled with a knfsd_fh structure
 418  *                      (a variable-length raw NFS file handle);
 419  *                      return code is the size in bytes of the file handle
 420  *      On error:       return code is negative errno value
 421  *
 422  * Note: Only AF_INET client addresses are passed in, since gd_addr
 423  * is the same size as a struct sockaddr_in.
 424  */
 425 static ssize_t write_getfs(struct file *file, char *buf, size_t size)
 426 {
 427         struct nfsctl_fsparm *data;
 428         struct sockaddr_in *sin;
 429         struct auth_domain *clp;
 430         int err = 0;
 431         struct knfsd_fh *res;
 432         struct in6_addr in6;
 433
 434         if (size < sizeof(*data))
 435                 return -EINVAL;
 436         data = (struct nfsctl_fsparm*)buf;
 437         err = -EPROTONOSUPPORT;
 438         if (data->gd_addr.sa_family != AF_INET)
 439                 goto out;
 440         sin = (struct sockaddr_in *)&data->gd_addr;
 441         if (data->gd_maxlen > NFS3_FHSIZE)
 442                 data->gd_maxlen = NFS3_FHSIZE;
 443
 444         res = (struct knfsd_fh*)buf;
 445
 446         exp_readlock();
 447
 448         ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &in6);
 449
 450         clp = auth_unix_lookup(&init_net, &in6);
 451         if (!clp)
 452                 err = -EPERM;
 453         else {
 454                 err = exp_rootfh(clp, data->gd_path, res, data->gd_maxlen);
 455                 auth_domain_put(clp);
 456         }
 457         exp_readunlock();
 458         if (err == 0)
 459                 err = res->fh_size + offsetof(struct knfsd_fh, fh_base);
 460  out:
 461         return err;
 462 }
 463
 464 /**
 465  * write_getfd - Get a fixed-length NFS file handle by path (used by mountd)
 466  *
 467  * Deprecated.  /proc/fs/nfsd/filehandle is preferred.
 468  * Function remains to support old versions of nfs-utils.
 469  *
 470  * Input:
 471  *                      buf:    struct nfsctl_fdparm
 472  *                              gd_addr:        socket address of client
 473  *                              gd_path:        '\0'-terminated C string
 474  *                                              containing pathname of
 475  *                                              directory in local file system
 476  *                              gd_version:     fdparm structure version
 477  *                      size:   size in bytes of passed in nfsctl_fdparm
 478  * Output:
 479  *      On success:     passed-in buffer filled with nfsctl_res
 480  *                      (a fixed-length raw NFS file handle);
 481  *                      return code is the size in bytes of the file handle
 482  *      On error:       return code is negative errno value
 483  *
 484  * Note: Only AF_INET client addresses are passed in, since gd_addr
 485  * is the same size as a struct sockaddr_in.
 486  */
 487 static ssize_t write_getfd(struct file *file, char *buf, size_t size)
 488 {
 489         struct nfsctl_fdparm *data;
 490         struct sockaddr_in *sin;
 491         struct auth_domain *clp;
 492         int err = 0;
 493         struct knfsd_fh fh;
 494         char *res;
 495         struct in6_addr in6;
 496
 497         if (size < sizeof(*data))
 498                 return -EINVAL;
 499         data = (struct nfsctl_fdparm*)buf;
 500         err = -EPROTONOSUPPORT;
 501         if (data->gd_addr.sa_family != AF_INET)
 502                 goto out;
 503         err = -EINVAL;
 504         if (data->gd_version < 2 || data->gd_version > NFSSVC_MAXVERS)
 505                 goto out;
 506
 507         res = buf;
 508         sin = (struct sockaddr_in *)&data->gd_addr;
 509         exp_readlock();
 510
 511         ipv6_addr_set_v4mapped(sin->sin_addr.s_addr, &in6);
 512
 513         clp = auth_unix_lookup(&init_net, &in6);
 514         if (!clp)
 515                 err = -EPERM;
 516         else {
 517                 err = exp_rootfh(clp, data->gd_path, &fh, NFS_FHSIZE);
 518                 auth_domain_put(clp);
 519         }
 520         exp_readunlock();
 521
 522         if (err == 0) {
 523                 memset(res,0, NFS_FHSIZE);
 524                 memcpy(res, &fh.fh_base, fh.fh_size);
 525                 err = NFS_FHSIZE;
 526         }
 527  out:
 528         return err;
 529 }
 530 #endif /* CONFIG_NFSD_DEPRECATED */
 531
 532 /**
 533  * write_unlock_ip - Release all locks used by a client
 534  *
 535  * Experimental.
 536  *
 537  * Input:
 538  *                      buf:    '\n'-terminated C string containing a
 539  *                              presentation format IP address
 540  *                      size:   length of C string in @buf
 541  * Output:
 542  *      On success:     returns zero if all specified locks were released;
 543  *                      returns one if one or more locks were not released
 544  *      On error:       return code is negative errno value
 545  */
 546 static ssize_t write_unlock_ip(struct file *file, char *buf, size_t size)
 547 {
 548         struct sockaddr_storage address;
 549         struct sockaddr *sap = (struct sockaddr *)&address;
 550         size_t salen = sizeof(address);
 551         char *fo_path;
 552
 553         /* sanity check */
 554         if (size == 0)
 555                 return -EINVAL;
 556
 557         if (buf[size-1] != '\n')
 558                 return -EINVAL;
 559
 560         fo_path = buf;
 561         if (qword_get(&buf, fo_path, size) < 0)
 562                 return -EINVAL;
 563
 564         if (rpc_pton(fo_path, size, sap, salen) == 0)
 565                 return -EINVAL;
 566
 567         return nlmsvc_unlock_all_by_ip(sap);
 568 }
 569
 570 /**
 571  * write_unlock_fs - Release all locks on a local file system
 572  *
 573  * Experimental.
 574  *
 575  * Input:
 576  *                      buf:    '\n'-terminated C string containing the
 577  *                              absolute pathname of a local file system
 578  *                      size:   length of C string in @buf
 579  * Output:
 580  *      On success:     returns zero if all specified locks were released;
 581  *                      returns one if one or more locks were not released
 582  *      On error:       return code is negative errno value
 583  */
 584 static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size)
 585 {
 586         struct path path;
 587         char *fo_path;
 588         int error;
 589
 590         /* sanity check */
 591         if (size == 0)
 592                 return -EINVAL;
 593
 594         if (buf[size-1] != '\n')
 595                 return -EINVAL;
 596
 597         fo_path = buf;
 598         if (qword_get(&buf, fo_path, size) < 0)
 599                 return -EINVAL;
 600
 601         error = kern_path(fo_path, 0, &path);
 602         if (error)
 603                 return error;
 604
 605         /*
 606          * XXX: Needs better sanity checking.  Otherwise we could end up
 607          * releasing locks on the wrong file system.
 608          *
 609          * For example:
 610          * 1.  Does the path refer to a directory?
 611          * 2.  Is that directory a mount point, or
 612          * 3.  Is that directory the root of an exported file system?
 613          */
 614         error = nlmsvc_unlock_all_by_sb(path.mnt->mnt_sb);
 615
 616         path_put(&path);
 617         return error;
 618 }
 619
 620 /**
 621  * write_filehandle - Get a variable-length NFS file handle by path
 622  *
 623  * On input, the buffer contains a '\n'-terminated C string comprised of
 624  * three alphanumeric words separated by whitespace.  The string may
 625  * contain escape sequences.
 626  *
 627  * Input:
 628  *                      buf:
 629  *                              domain:         client domain name
 630  *                              path:           export pathname
 631  *                              maxsize:        numeric maximum size of
 632  *                                              @buf
 633  *                      size:   length of C string in @buf
 634  * Output:
 635  *      On success:     passed-in buffer filled with '\n'-terminated C
 636  *                      string containing a ASCII hex text version
 637  *                      of the NFS file handle;
 638  *                      return code is the size in bytes of the string
 639  *      On error:       return code is negative errno value
 640  */
 641 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 642 {
 643         char *dname, *path;
 644         int uninitialized_var(maxsize);
 645         char *mesg = buf;
 646         int len;
 647         struct auth_domain *dom;
 648         struct knfsd_fh fh;
 649
 650         if (size == 0)
 651                 return -EINVAL;
 652
 653         if (buf[size-1] != '\n')
 654                 return -EINVAL;
 655         buf[size-1] = 0;
 656
 657         dname = mesg;
 658         len = qword_get(&mesg, dname, size);
 659         if (len <= 0)
 660                 return -EINVAL;
 661
 662         path = dname+len+1;
 663         len = qword_get(&mesg, path, size);
 664         if (len <= 0)
 665                 return -EINVAL;
 666
 667         len = get_int(&mesg, &maxsize);
 668         if (len)
 669                 return len;
 670
 671         if (maxsize < NFS_FHSIZE)
 672                 return -EINVAL;
 673         if (maxsize > NFS3_FHSIZE)
 674                 maxsize = NFS3_FHSIZE;
 675
 676         if (qword_get(&mesg, mesg, size)>0)
 677                 return -EINVAL;
 678
 679         /* we have all the words, they are in buf.. */
 680         dom = unix_domain_find(dname);
 681         if (!dom)
 682                 return -ENOMEM;
 683
 684         len = exp_rootfh(dom, path, &fh,  maxsize);
 685         auth_domain_put(dom);
 686         if (len)
 687                 return len;
 688
 689         mesg = buf;
 690         len = SIMPLE_TRANSACTION_LIMIT;
 691         qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
 692         mesg[-1] = '\n';
 693         return mesg - buf;
 694 }
 695
 696 /**
 697  * write_threads - Start NFSD, or report the current number of running threads
 698  *
 699  * Input:
 700  *                      buf:            ignored
 701  *                      size:           zero
 702  * Output:
 703  *      On success:     passed-in buffer filled with '\n'-terminated C
 704  *                      string numeric value representing the number of
 705  *                      running NFSD threads;
 706  *                      return code is the size in bytes of the string
 707  *      On error:       return code is zero
 708  *
 709  * OR
 710  *
 711  * Input:
 712  *                      buf:            C string containing an unsigned
 713  *                                      integer value representing the
 714  *                                      number of NFSD threads to start
 715  *                      size:           non-zero length of C string in @buf
 716  * Output:
 717  *      On success:     NFS service is started;
 718  *                      passed-in buffer filled with '\n'-terminated C
 719  *                      string numeric value representing the number of
 720  *                      running NFSD threads;
 721  *                      return code is the size in bytes of the string
 722  *      On error:       return code is zero or a negative errno value
 723  */
 724 static ssize_t write_threads(struct file *file, char *buf, size_t size)
 725 {
 726         char *mesg = buf;
 727         int rv;
 728         if (size > 0) {
 729                 int newthreads;
 730                 rv = get_int(&mesg, &newthreads);
 731                 if (rv)
 732                         return rv;
 733                 if (newthreads < 0)
 734                         return -EINVAL;
 735                 rv = nfsd_svc(NFS_PORT, newthreads);
 736                 if (rv < 0)
 737                         return rv;
 738         } else
 739                 rv = nfsd_nrthreads();
 740
 741         return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n", rv);
 742 }
 743
 744 /**
 745  * write_pool_threads - Set or report the current number of threads per pool
 746  *
 747  * Input:
 748  *                      buf:            ignored
 749  *                      size:           zero
 750  *
 751  * OR
 752  *
 753  * Input:
 754  *                      buf:            C string containing whitespace-
 755  *                                      separated unsigned integer values
 756  *                                      representing the number of NFSD
 757  *                                      threads to start in each pool
 758  *                      size:           non-zero length of C string in @buf
 759  * Output:
 760  *      On success:     passed-in buffer filled with '\n'-terminated C
 761  *                      string containing integer values representing the
 762  *                      number of NFSD threads in each pool;
 763  *                      return code is the size in bytes of the string
 764  *      On error:       return code is zero or a negative errno value
 765  */
 766 static ssize_t write_pool_threads(struct file *file, char *buf, size_t size)
 767 {
 768         /* if size > 0, look for an array of number of threads per node
 769          * and apply them  then write out number of threads per node as reply
 770          */
 771         char *mesg = buf;
 772         int i;
 773         int rv;
 774         int len;
 775         int npools;
 776         int *nthreads;
 777
 778         mutex_lock(&nfsd_mutex);
 779         npools = nfsd_nrpools();
 780         if (npools == 0) {
 781                 /*
 782                  * NFS is shut down.  The admin can start it by
 783                  * writing to the threads file but NOT the pool_threads
 784                  * file, sorry.  Report zero threads.
 785                  */
 786                 mutex_unlock(&nfsd_mutex);
 787                 strcpy(buf, "0\n");
 788                 return strlen(buf);
 789         }
 790
 791         nthreads = kcalloc(npools, sizeof(int), GFP_KERNEL);
 792         rv = -ENOMEM;
 793         if (nthreads == NULL)
 794                 goto out_free;
 795
 796         if (size > 0) {
 797                 for (i = 0; i < npools; i++) {
 798                         rv = get_int(&mesg, &nthreads[i]);
 799                         if (rv == -ENOENT)
 800                                 break;          /* fewer numbers than pools */
 801                         if (rv)
 802                                 goto out_free;  /* syntax error */
 803                         rv = -EINVAL;
 804                         if (nthreads[i] < 0)
 805                                 goto out_free;
 806                 }
 807                 rv = nfsd_set_nrthreads(i, nthreads);
 808                 if (rv)
 809                         goto out_free;
 810         }
 811
 812         rv = nfsd_get_nrthreads(npools, nthreads);
 813         if (rv)
 814                 goto out_free;
 815
 816         mesg = buf;
 817         size = SIMPLE_TRANSACTION_LIMIT;
 818         for (i = 0; i < npools && size > 0; i++) {
 819                 snprintf(mesg, size, "%d%c", nthreads[i], (i == npools-1 ? '\n' : ' '));
 820                 len = strlen(mesg);
 821                 size -= len;
 822                 mesg += len;
 823         }
 824         rv = mesg - buf;
 825 out_free:
 826         kfree(nthreads);
 827         mutex_unlock(&nfsd_mutex);
 828         return rv;
 829 }
 830
 831 static ssize_t __write_versions(struct file *file, char *buf, size_t size)
 832 {
 833         char *mesg = buf;
 834         char *vers, *minorp, sign;
 835         int len, num, remaining;
 836         unsigned minor;
 837         ssize_t tlen = 0;
 838         char *sep;
 839
 840         if (size>0) {
 841                 if (nfsd_serv)
 842                         /* Cannot change versions without updating
 843                          * nfsd_serv->sv_xdrsize, and reallocing
 844                          * rq_argp and rq_resp
 845                          */
 846                         return -EBUSY;
 847                 if (buf[size-1] != '\n')
 848                         return -EINVAL;
 849                 buf[size-1] = 0;
 850
 851                 vers = mesg;
 852                 len = qword_get(&mesg, vers, size);
 853                 if (len <= 0) return -EINVAL;
 854                 do {
 855                         sign = *vers;
 856                         if (sign == '+' || sign == '-')
 857                                 num = simple_strtol((vers+1), &minorp, 0);
 858                         else
 859                                 num = simple_strtol(vers, &minorp, 0);
 860                         if (*minorp == '.') {
 861                                 if (num < 4)
 862                                         return -EINVAL;
 863                                 minor = simple_strtoul(minorp+1, NULL, 0);
 864                                 if (minor == 0)
 865                                         return -EINVAL;
 866                                 if (nfsd_minorversion(minor, sign == '-' ?
 867                                                      NFSD_CLEAR : NFSD_SET) < 0)
 868                                         return -EINVAL;
 869                                 goto next;
 870                         }
 871                         switch(num) {
 872                         case 2:
 873                         case 3:
 874                         case 4:
 875                                 nfsd_vers(num, sign == '-' ? NFSD_CLEAR : NFSD_SET);
 876                                 break;
 877                         default:
 878                                 return -EINVAL;
 879                         }
 880                 next:
 881                         vers += len + 1;
 882                 } while ((len = qword_get(&mesg, vers, size)) > 0);
 883                 /* If all get turned off, turn them back on, as
 884                  * having no versions is BAD
 885                  */
 886                 nfsd_reset_versions();
 887         }
 888
 889         /* Now write current state into reply buffer */
 890         len = 0;
 891         sep = "";
 892         remaining = SIMPLE_TRANSACTION_LIMIT;
 893         for (num=2 ; num <= 4 ; num++)
 894                 if (nfsd_vers(num, NFSD_AVAIL)) {
 895                         len = snprintf(buf, remaining, "%s%c%d", sep,
 896                                        nfsd_vers(num, NFSD_TEST)?'+':'-',
 897                                        num);
 898                         sep = " ";
 899
 900                         if (len > remaining)
 901                                 break;
 902                         remaining -= len;
 903                         buf += len;
 904                         tlen += len;
 905                 }
 906         if (nfsd_vers(4, NFSD_AVAIL))
 907                 for (minor = 1; minor <= NFSD_SUPPORTED_MINOR_VERSION;
 908                      minor++) {
 909                         len = snprintf(buf, remaining, " %c4.%u",
 910                                         (nfsd_vers(4, NFSD_TEST) &&
 911                                          nfsd_minorversion(minor, NFSD_TEST)) ?
 912                                                 '+' : '-',
 913                                         minor);
 914
 915                         if (len > remaining)
 916                                 break;
 917                         remaining -= len;
 918                         buf += len;
 919                         tlen += len;
 920                 }
 921
 922         len = snprintf(buf, remaining, "\n");
 923         if (len > remaining)
 924                 return -EINVAL;
 925         return tlen + len;
 926 }
 927
 928 /**
 929  * write_versions - Set or report the available NFS protocol versions
 930  *
 931  * Input:
 932  *                      buf:            ignored
 933  *                      size:           zero
 934  * Output:
 935  *      On success:     passed-in buffer filled with '\n'-terminated C
 936  *                      string containing positive or negative integer
 937  *                      values representing the current status of each
 938  *                      protocol version;
 939  *                      return code is the size in bytes of the string
 940  *      On error:       return code is zero or a negative errno value
 941  *
 942  * OR
 943  *
 944  * Input:
 945  *                      buf:            C string containing whitespace-
 946  *                                      separated positive or negative
 947  *                                      integer values representing NFS
 948  *                                      protocol versions to enable ("+n")
 949  *                                      or disable ("-n")
 950  *                      size:           non-zero length of C string in @buf
 951  * Output:
 952  *      On success:     status of zero or more protocol versions has
 953  *                      been updated; passed-in buffer filled with
 954  *                      '\n'-terminated C string containing positive
 955  *                      or negative integer values representing the
 956  *                      current status of each protocol version;
 957  *                      return code is the size in bytes of the string
 958  *      On error:       return code is zero or a negative errno value
 959  */
 960 static ssize_t write_versions(struct file *file, char *buf, size_t size)
 961 {
 962         ssize_t rv;
 963
 964         mutex_lock(&nfsd_mutex);
 965         rv = __write_versions(file, buf, size);
 966         mutex_unlock(&nfsd_mutex);
 967         return rv;
 968 }
 969
 970 /*
 971  * Zero-length write.  Return a list of NFSD's current listener
 972  * transports.
 973  */
 974 static ssize_t __write_ports_names(char *buf)
 975 {
 976         if (nfsd_serv == NULL)
 977                 return 0;
 978         return svc_xprt_names(nfsd_serv, buf, SIMPLE_TRANSACTION_LIMIT);
 979 }
 980
 981 /*
 982  * A single 'fd' number was written, in which case it must be for
 983  * a socket of a supported family/protocol, and we use it as an
 984  * nfsd listener.
 985  */
 986 static ssize_t __write_ports_addfd(char *buf)
 987 {
 988         char *mesg = buf;
 989         int fd, err;
 990
 991         err = get_int(&mesg, &fd);
 992         if (err != 0 || fd < 0)
 993                 return -EINVAL;
 994
 995         err = nfsd_create_serv();
 996         if (err != 0)
 997                 return err;
 998
 999         err = svc_addsock(nfsd_serv, fd, buf, SIMPLE_TRANSACTION_LIMIT);
1000         if (err < 0) {
1001                 svc_destroy(nfsd_serv);
1002                 return err;
1003         }
1004
1005         /* Decrease the count, but don't shut down the service */
1006         nfsd_serv->sv_nrthreads--;
1007         return err;
1008 }
1009
1010 /*
1011  * A '-' followed by the 'name' of a socket means we close the socket.
1012  */
1013 static ssize_t __write_ports_delfd(char *buf)
1014 {
1015         char *toclose;
1016         int len = 0;
1017
1018         toclose = kstrdup(buf + 1, GFP_KERNEL);
1019         if (toclose == NULL)
1020                 return -ENOMEM;
1021
1022         if (nfsd_serv != NULL)
1023                 len = svc_sock_names(nfsd_serv, buf,
1024                                         SIMPLE_TRANSACTION_LIMIT, toclose);
1025         kfree(toclose);
1026         return len;
1027 }
1028
1029 /*
1030  * A transport listener is added by writing it's transport name and
1031  * a port number.
1032  */
1033 static ssize_t __write_ports_addxprt(char *buf)
1034 {
1035         char transport[16];
1036         struct svc_xprt *xprt;
1037         int port, err;
1038
1039         if (sscanf(buf, "%15s %4u", transport, &port) != 2)
1040                 return -EINVAL;
1041
1042         if (port < 1 || port > USHRT_MAX)
1043                 return -EINVAL;
1044
1045         err = nfsd_create_serv();
1046         if (err != 0)
1047                 return err;
1048
1049         err = svc_create_xprt(nfsd_serv, transport, &init_net,
1050                                 PF_INET, port, SVC_SOCK_ANONYMOUS);
1051         if (err < 0)
1052                 goto out_err;
1053
1054         err = svc_create_xprt(nfsd_serv, transport, &init_net,
1055                                 PF_INET6, port, SVC_SOCK_ANONYMOUS);
1056         if (err < 0 && err != -EAFNOSUPPORT)
1057                 goto out_close;
1058
1059         /* Decrease the count, but don't shut down the service */
1060         nfsd_serv->sv_nrthreads--;
1061         return 0;
1062 out_close:
1063         xprt = svc_find_xprt(nfsd_serv, transport, PF_INET, port);
1064         if (xprt != NULL) {
1065                 svc_close_xprt(xprt);
1066                 svc_xprt_put(xprt);
1067         }
1068 out_err:
1069         svc_destroy(nfsd_serv);
1070         return err;
1071 }
1072
1073 /*
1074  * A transport listener is removed by writing a "-", it's transport
1075  * name, and it's port number.
1076  */
1077 static ssize_t __write_ports_delxprt(char *buf)
1078 {
1079         struct svc_xprt *xprt;
1080         char transport[16];
1081         int port;
1082
1083         if (sscanf(&buf[1], "%15s %4u", transport, &port) != 2)
1084                 return -EINVAL;
1085
1086         if (port < 1 || port > USHRT_MAX || nfsd_serv == NULL)
1087                 return -EINVAL;
1088
1089         xprt = svc_find_xprt(nfsd_serv, transport, AF_UNSPEC, port);
1090         if (xprt == NULL)
1091                 return -ENOTCONN;
1092
1093         svc_close_xprt(xprt);
1094         svc_xprt_put(xprt);
1095         return 0;
1096 }
1097
1098 static ssize_t __write_ports(struct file *file, char *buf, size_t size)
1099 {
1100         if (size == 0)
1101                 return __write_ports_names(buf);
1102
1103         if (isdigit(buf[0]))
1104                 return __write_ports_addfd(buf);
1105
1106         if (buf[0] == '-' && isdigit(buf[1]))
1107                 return __write_ports_delfd(buf);
1108
1109         if (isalpha(buf[0]))
1110                 return __write_ports_addxprt(buf);
1111
1112         if (buf[0] == '-' && isalpha(buf[1]))
1113                 return __write_ports_delxprt(buf);
1114
1115         return -EINVAL;
1116 }
1117
1118 /**
1119  * write_ports - Pass a socket file descriptor or transport name to listen on
1120  *
1121  * Input:
1122  *                      buf:            ignored
1123  *                      size:           zero
1124  * Output:
1125  *      On success:     passed-in buffer filled with a '\n'-terminated C
1126  *                      string containing a whitespace-separated list of
1127  *                      named NFSD listeners;
1128  *                      return code is the size in bytes of the string
1129  *      On error:       return code is zero or a negative errno value
1130  *
1131  * OR
1132  *
1133  * Input:
1134  *                      buf:            C string containing an unsigned
1135  *                                      integer value representing a bound
1136  *                                      but unconnected socket that is to be
1137  *                                      used as an NFSD listener; listen(3)
1138  *                                      must be called for a SOCK_STREAM
1139  *                                      socket, otherwise it is ignored
1140  *                      size:           non-zero length of C string in @buf
1141  * Output:
1142  *      On success:     NFS service is started;
1143  *                      passed-in buffer filled with a '\n'-terminated C
1144  *                      string containing a unique alphanumeric name of
1145  *                      the listener;
1146  *                      return code is the size in bytes of the string
1147  *      On error:       return code is a negative errno value
1148  *
1149  * OR
1150  *
1151  * Input:
1152  *                      buf:            C string containing a "-" followed
1153  *                                      by an integer value representing a
1154  *                                      previously passed in socket file
1155  *                                      descriptor
1156  *                      size:           non-zero length of C string in @buf
1157  * Output:
1158  *      On success:     NFS service no longer listens on that socket;
1159  *                      passed-in buffer filled with a '\n'-terminated C
1160  *                      string containing a unique name of the listener;
1161  *                      return code is the size in bytes of the string
1162  *      On error:       return code is a negative errno value
1163  *
1164  * OR
1165  *
1166  * Input:
1167  *                      buf:            C string containing a transport
1168  *                                      name and an unsigned integer value
1169  *                                      representing the port to listen on,
1170  *                                      separated by whitespace
1171  *                      size:           non-zero length of C string in @buf
1172  * Output:
1173  *      On success:     returns zero; NFS service is started
1174  *      On error:       return code is a negative errno value
1175  *
1176  * OR
1177  *
1178  * Input:
1179  *                      buf:            C string containing a "-" followed
1180  *                                      by a transport name and an unsigned
1181  *                                      integer value representing the port
1182  *                                      to listen on, separated by whitespace
1183  *                      size:           non-zero length of C string in @buf
1184  * Output:
1185  *      On success:     returns zero; NFS service no longer listens
1186  *                      on that transport
1187  *      On error:       return code is a negative errno value
1188  */
1189 static ssize_t write_ports(struct file *file, char *buf, size_t size)
1190 {
1191         ssize_t rv;
1192
1193         mutex_lock(&nfsd_mutex);
1194         rv = __write_ports(file, buf, size);
1195         mutex_unlock(&nfsd_mutex);
1196         return rv;
1197 }
1198
1199
1200 int nfsd_max_blksize;
1201
1202 /**
1203  * write_maxblksize - Set or report the current NFS blksize
1204  *
1205  * Input:
1206  *                      buf:            ignored
1207  *                      size:           zero
1208  *
1209  * OR
1210  *
1211  * Input:
1212  *                      buf:            C string containing an unsigned
1213  *                                      integer value representing the new
1214  *                                      NFS blksize
1215  *                      size:           non-zero length of C string in @buf
1216  * Output:
1217  *      On success:     passed-in buffer filled with '\n'-terminated C string
1218  *                      containing numeric value of the current NFS blksize
1219  *                      setting;
1220  *                      return code is the size in bytes of the string
1221  *      On error:       return code is zero or a negative errno value
1222  */
1223 static ssize_t write_maxblksize(struct file *file, char *buf, size_t size)
1224 {
1225         char *mesg = buf;
1226         if (size > 0) {
1227                 int bsize;
1228                 int rv = get_int(&mesg, &bsize);
1229                 if (rv)
1230                         return rv;
1231                 /* force bsize into allowed range and
1232                  * required alignment.
1233                  */
1234                 if (bsize < 1024)
1235                         bsize = 1024;
1236                 if (bsize > NFSSVC_MAXBLKSIZE)
1237                         bsize = NFSSVC_MAXBLKSIZE;
1238                 bsize &= ~(1024-1);
1239                 mutex_lock(&nfsd_mutex);
1240                 if (nfsd_serv) {
1241                         mutex_unlock(&nfsd_mutex);
1242                         return -EBUSY;
1243                 }
1244                 nfsd_max_blksize = bsize;
1245                 mutex_unlock(&nfsd_mutex);
1246         }
1247
1248         return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%d\n",
1249                                                         nfsd_max_blksize);
1250 }
1251
1252 #ifdef CONFIG_NFSD_V4
1253 static ssize_t __nfsd4_write_time(struct file *file, char *buf, size_t size, time_t *time)
1254 {
1255         char *mesg = buf;
1256         int rv, i;
1257
1258         if (size > 0) {
1259                 if (nfsd_serv)
1260                         return -EBUSY;
1261                 rv = get_int(&mesg, &i);
1262                 if (rv)
1263                         return rv;
1264                 /*
1265                  * Some sanity checking.  We don't have a reason for
1266                  * these particular numbers, but problems with the
1267                  * extremes are:
1268                  *      - Too short: the briefest network outage may
1269                  *        cause clients to lose all their locks.  Also,
1270                  *        the frequent polling may be wasteful.
1271                  *      - Too long: do you really want reboot recovery
1272                  *        to take more than an hour?  Or to make other
1273                  *        clients wait an hour before being able to
1274                  *        revoke a dead client's locks?
1275                  */
1276                 if (i < 10 || i > 3600)
1277                         return -EINVAL;
1278                 *time = i;
1279         }
1280
1281         return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%ld\n", *time);
1282 }
1283
1284 static ssize_t nfsd4_write_time(struct file *file, char *buf, size_t size, time_t *time)
1285 {
1286         ssize_t rv;
1287
1288         mutex_lock(&nfsd_mutex);
1289         rv = __nfsd4_write_time(file, buf, size, time);
1290         mutex_unlock(&nfsd_mutex);
1291         return rv;
1292 }
1293
1294 /**
1295  * write_leasetime - Set or report the current NFSv4 lease time
1296  *
1297  * Input:
1298  *                      buf:            ignored
1299  *                      size:           zero
1300  *
1301  * OR
1302  *
1303  * Input:
1304  *                      buf:            C string containing an unsigned
1305  *                                      integer value representing the new
1306  *                                      NFSv4 lease expiry time
1307  *                      size:           non-zero length of C string in @buf
1308  * Output:
1309  *      On success:     passed-in buffer filled with '\n'-terminated C
1310  *                      string containing unsigned integer value of the
1311  *                      current lease expiry time;
1312  *                      return code is the size in bytes of the string
1313  *      On error:       return code is zero or a negative errno value
1314  */
1315 static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
1316 {
1317         return nfsd4_write_time(file, buf, size, &nfsd4_lease);
1318 }
1319
1320 /**
1321  * write_gracetime - Set or report current NFSv4 grace period time
1322  *
1323  * As above, but sets the time of the NFSv4 grace period.
1324  *
1325  * Note this should never be set to less than the *previous*
1326  * lease-period time, but we don't try to enforce this.  (In the common
1327  * case (a new boot), we don't know what the previous lease time was
1328  * anyway.)
1329  */
1330 static ssize_t write_gracetime(struct file *file, char *buf, size_t size)
1331 {
1332         return nfsd4_write_time(file, buf, size, &nfsd4_grace);
1333 }
1334
1335 extern char *nfs4_recoverydir(void);
1336
1337 static ssize_t __write_recoverydir(struct file *file, char *buf, size_t size)
1338 {
1339         char *mesg = buf;
1340         char *recdir;
1341         int len, status;
1342
1343         if (size > 0) {
1344                 if (nfsd_serv)
1345                         return -EBUSY;
1346                 if (size > PATH_MAX || buf[size-1] != '\n')
1347                         return -EINVAL;
1348                 buf[size-1] = 0;
1349
1350                 recdir = mesg;
1351                 len = qword_get(&mesg, recdir, size);
1352                 if (len <= 0)
1353                         return -EINVAL;
1354
1355                 status = nfs4_reset_recoverydir(recdir);
1356                 if (status)
1357                         return status;
1358         }
1359
1360         return scnprintf(buf, SIMPLE_TRANSACTION_LIMIT, "%s\n",
1361                                                         nfs4_recoverydir());
1362 }
1363
1364 /**
1365  * write_recoverydir - Set or report the pathname of the recovery directory
1366  *
1367  * Input:
1368  *                      buf:            ignored
1369  *                      size:           zero
1370  *
1371  * OR
1372  *
1373  * Input:
1374  *                      buf:            C string containing the pathname
1375  *                                      of the directory on a local file
1376  *                                      system containing permanent NFSv4
1377  *                                      recovery data
1378  *                      size:           non-zero length of C string in @buf
1379  * Output:
1380  *      On success:     passed-in buffer filled with '\n'-terminated C string
1381  *                      containing the current recovery pathname setting;
1382  *                      return code is the size in bytes of the string
1383  *      On error:       return code is zero or a negative errno value
1384  */
1385 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
1386 {
1387         ssize_t rv;
1388
1389         mutex_lock(&nfsd_mutex);
1390         rv = __write_recoverydir(file, buf, size);
1391         mutex_unlock(&nfsd_mutex);
1392         return rv;
1393 }
1394
1395 #endif
1396
1397 /*----------------------------------------------------------------------------*/
1398 /*
1399  *      populating the filesystem.
1400  */
1401
1402 static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
1403 {
1404         static struct tree_descr nfsd_files[] = {
1405 #ifdef CONFIG_NFSD_DEPRECATED
1406                 [NFSD_Svc] = {".svc", &transaction_ops, S_IWUSR},
1407                 [NFSD_Add] = {".add", &transaction_ops, S_IWUSR},
1408                 [NFSD_Del] = {".del", &transaction_ops, S_IWUSR},
1409                 [NFSD_Export] = {".export", &transaction_ops, S_IWUSR},
1410                 [NFSD_Unexport] = {".unexport", &transaction_ops, S_IWUSR},
1411                 [NFSD_Getfd] = {".getfd", &transaction_ops, S_IWUSR|S_IRUSR},
1412                 [NFSD_Getfs] = {".getfs", &transaction_ops, S_IWUSR|S_IRUSR},
1413 #endif
1414                 [NFSD_List] = {"exports", &exports_operations, S_IRUGO},
1415                 [NFSD_Export_features] = {"export_features",
1416                                         &export_features_operations, S_IRUGO},
1417                 [NFSD_FO_UnlockIP] = {"unlock_ip",
1418                                         &transaction_ops, S_IWUSR|S_IRUSR},
1419                 [NFSD_FO_UnlockFS] = {"unlock_filesystem",
1420                                         &transaction_ops, S_IWUSR|S_IRUSR},
1421                 [NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
1422                 [NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
1423                 [NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
1424                 [NFSD_Pool_Stats] = {"pool_stats", &pool_stats_operations, S_IRUGO},
1425                 [NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
1426                 [NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
1427                 [NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
1428                 [NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", &supported_enctypes_ops, S_IRUGO},
1429 #ifdef CONFIG_NFSD_V4
1430                 [NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
1431                 [NFSD_Gracetime] = {"nfsv4gracetime", &transaction_ops, S_IWUSR|S_IRUSR},
1432                 [NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
1433 #endif
1434                 /* last one */ {""}
1435         };
1436         return simple_fill_super(sb, 0x6e667364, nfsd_files);
1437 }
1438
1439 static struct dentry *nfsd_mount(struct file_system_type *fs_type,
1440         int flags, const char *dev_name, void *data)
1441 {
1442         return mount_single(fs_type, flags, data, nfsd_fill_super);
1443 }
1444
1445 static struct file_system_type nfsd_fs_type = {
1446         .owner          = THIS_MODULE,
1447         .name           = "nfsd",
1448         .mount          = nfsd_mount,
1449         .kill_sb        = kill_litter_super,
1450 };
1451
1452 #ifdef CONFIG_PROC_FS
1453 static int create_proc_exports_entry(void)
1454 {
1455         struct proc_dir_entry *entry;
1456
1457         entry = proc_mkdir("fs/nfs", NULL);
1458         if (!entry)
1459                 return -ENOMEM;
1460         entry = proc_create("exports", 0, entry, &exports_operations);
1461         if (!entry)
1462                 return -ENOMEM;
1463         return 0;
1464 }
1465 #else /* CONFIG_PROC_FS */
1466 static int create_proc_exports_entry(void)
1467 {
1468         return 0;
1469 }
1470 #endif
1471
1472 static int __init init_nfsd(void)
1473 {
1474         int retval;
1475         printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
1476
1477         retval = nfs4_state_init(); /* nfs4 locking state */
1478         if (retval)
1479                 return retval;
1480         nfsd_stat_init();       /* Statistics */
1481         retval = nfsd_reply_cache_init();
1482         if (retval)
1483                 goto out_free_stat;
1484         retval = nfsd_export_init();
1485         if (retval)
1486                 goto out_free_cache;
1487         nfsd_lockd_init();      /* lockd->nfsd callbacks */
1488         retval = nfsd_idmap_init();
1489         if (retval)
1490                 goto out_free_lockd;
1491         retval = create_proc_exports_entry();
1492         if (retval)
1493                 goto out_free_idmap;
1494         retval = register_filesystem(&nfsd_fs_type);
1495         if (retval)
1496                 goto out_free_all;
1497         return 0;
1498 out_free_all:
1499         remove_proc_entry("fs/nfs/exports", NULL);
1500         remove_proc_entry("fs/nfs", NULL);
1501 out_free_idmap:
1502         nfsd_idmap_shutdown();
1503 out_free_lockd:
1504         nfsd_lockd_shutdown();
1505         nfsd_export_shutdown();
1506 out_free_cache:
1507         nfsd_reply_cache_shutdown();
1508 out_free_stat:
1509         nfsd_stat_shutdown();
1510         nfsd4_free_slabs();
1511         return retval;
1512 }
1513
1514 static void __exit exit_nfsd(void)
1515 {
1516         nfsd_export_shutdown();
1517         nfsd_reply_cache_shutdown();
1518         remove_proc_entry("fs/nfs/exports", NULL);
1519         remove_proc_entry("fs/nfs", NULL);
1520         nfsd_stat_shutdown();
1521         nfsd_lockd_shutdown();
1522         nfsd_idmap_shutdown();
1523         nfsd4_free_slabs();
1524         unregister_filesystem(&nfsd_fs_type);
1525 }
1526
1527 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
1528 MODULE_LICENSE("GPL");
1529 module_init(init_nfsd)
1530 module_exit(exit_nfsd)