fs/nfsd/export.c

   1 #define MSNFS   /* HACK HACK */
   2 /*
   3  * linux/fs/nfsd/export.c
   4  *
   5  * NFS exporting and validation.
   6  *
   7  * We maintain a list of clients, each of which has a list of
   8  * exports. To export an fs to a given client, you first have
   9  * to create the client entry with NFSCTL_ADDCLIENT, which
  10  * creates a client control block and adds it to the hash
  11  * table. Then, you call NFSCTL_EXPORT for each fs.
  12  *
  13  *
  14  * Copyright (C) 1995, 1996 Olaf Kirch, <okir@monad.swb.de>
  15  */
  16
  17 #include <linux/unistd.h>
  18 #include <linux/slab.h>
  19 #include <linux/sched.h>
  20 #include <linux/stat.h>
  21 #include <linux/in.h>
  22 #include <linux/seq_file.h>
  23 #include <linux/syscalls.h>
  24 #include <linux/rwsem.h>
  25 #include <linux/dcache.h>
  26 #include <linux/namei.h>
  27 #include <linux/mount.h>
  28 #include <linux/hash.h>
  29 #include <linux/module.h>
  30
  31 #include <linux/sunrpc/svc.h>
  32 #include <linux/nfsd/nfsd.h>
  33 #include <linux/nfsd/nfsfh.h>
  34 #include <linux/nfsd/syscall.h>
  35 #include <linux/lockd/bind.h>
  36
  37 #define NFSDDBG_FACILITY        NFSDDBG_EXPORT
  38
  39 typedef struct auth_domain      svc_client;
  40 typedef struct svc_export       svc_export;
  41
  42 static void             exp_do_unexport(svc_export *unexp);
  43 static int              exp_verify_string(char *cp, int max);
  44
  45 /*
  46  * We have two caches.
  47  * One maps client+vfsmnt+dentry to export options - the export map
  48  * The other maps client+filehandle-fragment to export options. - the expkey map
  49  *
  50  * The export options are actually stored in the first map, and the
  51  * second map contains a reference to the entry in the first map.
  52  */
  53
  54 #define EXPKEY_HASHBITS         8
  55 #define EXPKEY_HASHMAX          (1 << EXPKEY_HASHBITS)
  56 #define EXPKEY_HASHMASK         (EXPKEY_HASHMAX -1)
  57 static struct cache_head *expkey_table[EXPKEY_HASHMAX];
  58
  59 static void expkey_put(struct kref *ref)
  60 {
  61         struct svc_expkey *key = container_of(ref, struct svc_expkey, h.ref);
  62
  63         if (test_bit(CACHE_VALID, &key->h.flags) &&
  64             !test_bit(CACHE_NEGATIVE, &key->h.flags)) {
  65                 dput(key->ek_dentry);
  66                 mntput(key->ek_mnt);
  67         }
  68         auth_domain_put(key->ek_client);
  69         kfree(key);
  70 }
  71
  72 static void expkey_request(struct cache_detail *cd,
  73                            struct cache_head *h,
  74                            char **bpp, int *blen)
  75 {
  76         /* client fsidtype \xfsid */
  77         struct svc_expkey *ek = container_of(h, struct svc_expkey, h);
  78         char type[5];
  79
  80         qword_add(bpp, blen, ek->ek_client->name);
  81         snprintf(type, 5, "%d", ek->ek_fsidtype);
  82         qword_add(bpp, blen, type);
  83         qword_addhex(bpp, blen, (char*)ek->ek_fsid, key_len(ek->ek_fsidtype));
  84         (*bpp)[-1] = '\n';
  85 }
  86
  87 static struct svc_expkey *svc_expkey_update(struct svc_expkey *new, struct svc_expkey *old);
  88 static struct svc_expkey *svc_expkey_lookup(struct svc_expkey *);
  89 static struct cache_detail svc_expkey_cache;
  90
  91 static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)
  92 {
  93         /* client fsidtype fsid [path] */
  94         char *buf;
  95         int len;
  96         struct auth_domain *dom = NULL;
  97         int err;
  98         int fsidtype;
  99         char *ep;
 100         struct svc_expkey key;
 101         struct svc_expkey *ek;
 102
 103         if (mesg[mlen-1] != '\n')
 104                 return -EINVAL;
 105         mesg[mlen-1] = 0;
 106
 107         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 108         err = -ENOMEM;
 109         if (!buf) goto out;
 110
 111         err = -EINVAL;
 112         if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
 113                 goto out;
 114
 115         err = -ENOENT;
 116         dom = auth_domain_find(buf);
 117         if (!dom)
 118                 goto out;
 119         dprintk("found domain %s\n", buf);
 120
 121         err = -EINVAL;
 122         if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
 123                 goto out;
 124         fsidtype = simple_strtoul(buf, &ep, 10);
 125         if (*ep)
 126                 goto out;
 127         dprintk("found fsidtype %d\n", fsidtype);
 128         if (key_len(fsidtype)==0) /* invalid type */
 129                 goto out;
 130         if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
 131                 goto out;
 132         dprintk("found fsid length %d\n", len);
 133         if (len != key_len(fsidtype))
 134                 goto out;
 135
 136         /* OK, we seem to have a valid key */
 137         key.h.flags = 0;
 138         key.h.expiry_time = get_expiry(&mesg);
 139         if (key.h.expiry_time == 0)
 140                 goto out;
 141
 142         key.ek_client = dom;
 143         key.ek_fsidtype = fsidtype;
 144         memcpy(key.ek_fsid, buf, len);
 145
 146         ek = svc_expkey_lookup(&key);
 147         err = -ENOMEM;
 148         if (!ek)
 149                 goto out;
 150
 151         /* now we want a pathname, or empty meaning NEGATIVE  */
 152         err = -EINVAL;
 153         if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0)
 154                 goto out;
 155         dprintk("Path seems to be <%s>\n", buf);
 156         err = 0;
 157         if (len == 0) {
 158                 set_bit(CACHE_NEGATIVE, &key.h.flags);
 159                 ek = svc_expkey_update(&key, ek);
 160                 if (ek)
 161                         cache_put(&ek->h, &svc_expkey_cache);
 162                 else err = -ENOMEM;
 163         } else {
 164                 struct nameidata nd;
 165                 err = path_lookup(buf, 0, &nd);
 166                 if (err)
 167                         goto out;
 168
 169                 dprintk("Found the path %s\n", buf);
 170                 key.ek_mnt = nd.mnt;
 171                 key.ek_dentry = nd.dentry;
 172
 173                 ek = svc_expkey_update(&key, ek);
 174                 if (ek)
 175                         cache_put(&ek->h, &svc_expkey_cache);
 176                 else
 177                         err = -ENOMEM;
 178                 path_release(&nd);
 179         }
 180         cache_flush();
 181  out:
 182         if (dom)
 183                 auth_domain_put(dom);
 184         kfree(buf);
 185         return err;
 186 }
 187
 188 static int expkey_show(struct seq_file *m,
 189                        struct cache_detail *cd,
 190                        struct cache_head *h)
 191 {
 192         struct svc_expkey *ek ;
 193         int i;
 194
 195         if (h ==NULL) {
 196                 seq_puts(m, "#domain fsidtype fsid [path]\n");
 197                 return 0;
 198         }
 199         ek = container_of(h, struct svc_expkey, h);
 200         seq_printf(m, "%s %d 0x", ek->ek_client->name,
 201                    ek->ek_fsidtype);
 202         for (i=0; i < key_len(ek->ek_fsidtype)/4; i++)
 203                 seq_printf(m, "%08x", ek->ek_fsid[i]);
 204         if (test_bit(CACHE_VALID, &h->flags) &&
 205             !test_bit(CACHE_NEGATIVE, &h->flags)) {
 206                 seq_printf(m, " ");
 207                 seq_path(m, ek->ek_mnt, ek->ek_dentry, "\\ \t\n");
 208         }
 209         seq_printf(m, "\n");
 210         return 0;
 211 }
 212
 213 static inline int expkey_match (struct cache_head *a, struct cache_head *b)
 214 {
 215         struct svc_expkey *orig = container_of(a, struct svc_expkey, h);
 216         struct svc_expkey *new = container_of(b, struct svc_expkey, h);
 217
 218         if (orig->ek_fsidtype != new->ek_fsidtype ||
 219             orig->ek_client != new->ek_client ||
 220             memcmp(orig->ek_fsid, new->ek_fsid, key_len(orig->ek_fsidtype)) != 0)
 221                 return 0;
 222         return 1;
 223 }
 224
 225 static inline void expkey_init(struct cache_head *cnew,
 226                                    struct cache_head *citem)
 227 {
 228         struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
 229         struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
 230
 231         kref_get(&item->ek_client->ref);
 232         new->ek_client = item->ek_client;
 233         new->ek_fsidtype = item->ek_fsidtype;
 234
 235         memcpy(new->ek_fsid, item->ek_fsid, sizeof(new->ek_fsid));
 236 }
 237
 238 static inline void expkey_update(struct cache_head *cnew,
 239                                    struct cache_head *citem)
 240 {
 241         struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
 242         struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
 243
 244         new->ek_mnt = mntget(item->ek_mnt);
 245         new->ek_dentry = dget(item->ek_dentry);
 246 }
 247
 248 static struct cache_head *expkey_alloc(void)
 249 {
 250         struct svc_expkey *i = kmalloc(sizeof(*i), GFP_KERNEL);
 251         if (i)
 252                 return &i->h;
 253         else
 254                 return NULL;
 255 }
 256
 257 static struct cache_detail svc_expkey_cache = {
 258         .owner          = THIS_MODULE,
 259         .hash_size      = EXPKEY_HASHMAX,
 260         .hash_table     = expkey_table,
 261         .name           = "nfsd.fh",
 262         .cache_put      = expkey_put,
 263         .cache_request  = expkey_request,
 264         .cache_parse    = expkey_parse,
 265         .cache_show     = expkey_show,
 266         .match          = expkey_match,
 267         .init           = expkey_init,
 268         .update         = expkey_update,
 269         .alloc          = expkey_alloc,
 270 };
 271
 272 static struct svc_expkey *
 273 svc_expkey_lookup(struct svc_expkey *item)
 274 {
 275         struct cache_head *ch;
 276         int hash = item->ek_fsidtype;
 277         char * cp = (char*)item->ek_fsid;
 278         int len = key_len(item->ek_fsidtype);
 279
 280         hash ^= hash_mem(cp, len, EXPKEY_HASHBITS);
 281         hash ^= hash_ptr(item->ek_client, EXPKEY_HASHBITS);
 282         hash &= EXPKEY_HASHMASK;
 283
 284         ch = sunrpc_cache_lookup(&svc_expkey_cache, &item->h,
 285                                  hash);
 286         if (ch)
 287                 return container_of(ch, struct svc_expkey, h);
 288         else
 289                 return NULL;
 290 }
 291
 292 static struct svc_expkey *
 293 svc_expkey_update(struct svc_expkey *new, struct svc_expkey *old)
 294 {
 295         struct cache_head *ch;
 296         int hash = new->ek_fsidtype;
 297         char * cp = (char*)new->ek_fsid;
 298         int len = key_len(new->ek_fsidtype);
 299
 300         hash ^= hash_mem(cp, len, EXPKEY_HASHBITS);
 301         hash ^= hash_ptr(new->ek_client, EXPKEY_HASHBITS);
 302         hash &= EXPKEY_HASHMASK;
 303
 304         ch = sunrpc_cache_update(&svc_expkey_cache, &new->h,
 305                                  &old->h, hash);
 306         if (ch)
 307                 return container_of(ch, struct svc_expkey, h);
 308         else
 309                 return NULL;
 310 }
 311
 312
 313 #define EXPORT_HASHBITS         8
 314 #define EXPORT_HASHMAX          (1<< EXPORT_HASHBITS)
 315 #define EXPORT_HASHMASK         (EXPORT_HASHMAX -1)
 316
 317 static struct cache_head *export_table[EXPORT_HASHMAX];
 318
 319 static void nfsd4_fslocs_free(struct nfsd4_fs_locations *fsloc)
 320 {
 321         int i;
 322
 323         for (i = 0; i < fsloc->locations_count; i++) {
 324                 kfree(fsloc->locations[i].path);
 325                 kfree(fsloc->locations[i].hosts);
 326         }
 327         kfree(fsloc->locations);
 328 }
 329
 330 static void svc_export_put(struct kref *ref)
 331 {
 332         struct svc_export *exp = container_of(ref, struct svc_export, h.ref);
 333         dput(exp->ex_dentry);
 334         mntput(exp->ex_mnt);
 335         auth_domain_put(exp->ex_client);
 336         kfree(exp->ex_path);
 337         nfsd4_fslocs_free(&exp->ex_fslocs);
 338         kfree(exp);
 339 }
 340
 341 static void svc_export_request(struct cache_detail *cd,
 342                                struct cache_head *h,
 343                                char **bpp, int *blen)
 344 {
 345         /*  client path */
 346         struct svc_export *exp = container_of(h, struct svc_export, h);
 347         char *pth;
 348
 349         qword_add(bpp, blen, exp->ex_client->name);
 350         pth = d_path(exp->ex_dentry, exp->ex_mnt, *bpp, *blen);
 351         if (IS_ERR(pth)) {
 352                 /* is this correct? */
 353                 (*bpp)[0] = '\n';
 354                 return;
 355         }
 356         qword_add(bpp, blen, pth);
 357         (*bpp)[-1] = '\n';
 358 }
 359
 360 static struct svc_export *svc_export_update(struct svc_export *new,
 361                                             struct svc_export *old);
 362 static struct svc_export *svc_export_lookup(struct svc_export *);
 363
 364 static int check_export(struct inode *inode, int flags, unsigned char *uuid)
 365 {
 366
 367         /* We currently export only dirs and regular files.
 368          * This is what umountd does.
 369          */
 370         if (!S_ISDIR(inode->i_mode) &&
 371             !S_ISREG(inode->i_mode))
 372                 return -ENOTDIR;
 373
 374         /* There are two requirements on a filesystem to be exportable.
 375          * 1:  We must be able to identify the filesystem from a number.
 376          *       either a device number (so FS_REQUIRES_DEV needed)
 377          *       or an FSID number (so NFSEXP_FSID or ->uuid is needed).
 378          * 2:  We must be able to find an inode from a filehandle.
 379          *       This means that s_export_op must be set.
 380          */
 381         if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
 382             !(flags & NFSEXP_FSID) &&
 383             uuid == NULL) {
 384                 dprintk("exp_export: export of non-dev fs without fsid\n");
 385                 return -EINVAL;
 386         }
 387         if (!inode->i_sb->s_export_op) {
 388                 dprintk("exp_export: export of invalid fs type.\n");
 389                 return -EINVAL;
 390         }
 391
 392         /* Ok, we can export it */;
 393         if (!inode->i_sb->s_export_op->find_exported_dentry)
 394                 inode->i_sb->s_export_op->find_exported_dentry =
 395                         find_exported_dentry;
 396         return 0;
 397
 398 }
 399
 400 #ifdef CONFIG_NFSD_V4
 401
 402 static int
 403 fsloc_parse(char **mesg, char *buf, struct nfsd4_fs_locations *fsloc)
 404 {
 405         int len;
 406         int migrated, i, err;
 407
 408         /* listsize */
 409         err = get_int(mesg, &fsloc->locations_count);
 410         if (err)
 411                 return err;
 412         if (fsloc->locations_count > MAX_FS_LOCATIONS)
 413                 return -EINVAL;
 414         if (fsloc->locations_count == 0)
 415                 return 0;
 416
 417         fsloc->locations = kzalloc(fsloc->locations_count
 418                         * sizeof(struct nfsd4_fs_location), GFP_KERNEL);
 419         if (!fsloc->locations)
 420                 return -ENOMEM;
 421         for (i=0; i < fsloc->locations_count; i++) {
 422                 /* colon separated host list */
 423                 err = -EINVAL;
 424                 len = qword_get(mesg, buf, PAGE_SIZE);
 425                 if (len <= 0)
 426                         goto out_free_all;
 427                 err = -ENOMEM;
 428                 fsloc->locations[i].hosts = kstrdup(buf, GFP_KERNEL);
 429                 if (!fsloc->locations[i].hosts)
 430                         goto out_free_all;
 431                 err = -EINVAL;
 432                 /* slash separated path component list */
 433                 len = qword_get(mesg, buf, PAGE_SIZE);
 434                 if (len <= 0)
 435                         goto out_free_all;
 436                 err = -ENOMEM;
 437                 fsloc->locations[i].path = kstrdup(buf, GFP_KERNEL);
 438                 if (!fsloc->locations[i].path)
 439                         goto out_free_all;
 440         }
 441         /* migrated */
 442         err = get_int(mesg, &migrated);
 443         if (err)
 444                 goto out_free_all;
 445         err = -EINVAL;
 446         if (migrated < 0 || migrated > 1)
 447                 goto out_free_all;
 448         fsloc->migrated = migrated;
 449         return 0;
 450 out_free_all:
 451         nfsd4_fslocs_free(fsloc);
 452         return err;
 453 }
 454
 455 #else /* CONFIG_NFSD_V4 */
 456 static inline int fsloc_parse(char **mesg, char *buf, struct nfsd4_fs_locations *fsloc) { return 0; }
 457 #endif
 458
 459 static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
 460 {
 461         /* client path expiry [flags anonuid anongid fsid] */
 462         char *buf;
 463         int len;
 464         int err;
 465         struct auth_domain *dom = NULL;
 466         struct nameidata nd;
 467         struct svc_export exp, *expp;
 468         int an_int;
 469
 470         nd.dentry = NULL;
 471         exp.ex_path = NULL;
 472
 473         if (mesg[mlen-1] != '\n')
 474                 return -EINVAL;
 475         mesg[mlen-1] = 0;
 476
 477         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 478         err = -ENOMEM;
 479         if (!buf) goto out;
 480
 481         /* client */
 482         len = qword_get(&mesg, buf, PAGE_SIZE);
 483         err = -EINVAL;
 484         if (len <= 0) goto out;
 485
 486         err = -ENOENT;
 487         dom = auth_domain_find(buf);
 488         if (!dom)
 489                 goto out;
 490
 491         /* path */
 492         err = -EINVAL;
 493         if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
 494                 goto out;
 495         err = path_lookup(buf, 0, &nd);
 496         if (err) goto out_no_path;
 497
 498         exp.h.flags = 0;
 499         exp.ex_client = dom;
 500         exp.ex_mnt = nd.mnt;
 501         exp.ex_dentry = nd.dentry;
 502         exp.ex_path = kstrdup(buf, GFP_KERNEL);
 503         err = -ENOMEM;
 504         if (!exp.ex_path)
 505                 goto out;
 506
 507         /* expiry */
 508         err = -EINVAL;
 509         exp.h.expiry_time = get_expiry(&mesg);
 510         if (exp.h.expiry_time == 0)
 511                 goto out;
 512
 513         /* fs locations */
 514         exp.ex_fslocs.locations = NULL;
 515         exp.ex_fslocs.locations_count = 0;
 516         exp.ex_fslocs.migrated = 0;
 517
 518         exp.ex_uuid = NULL;
 519
 520         /* flags */
 521         err = get_int(&mesg, &an_int);
 522         if (err == -ENOENT)
 523                 set_bit(CACHE_NEGATIVE, &exp.h.flags);
 524         else {
 525                 if (err || an_int < 0) goto out;
 526                 exp.ex_flags= an_int;
 527
 528                 /* anon uid */
 529                 err = get_int(&mesg, &an_int);
 530                 if (err) goto out;
 531                 exp.ex_anon_uid= an_int;
 532
 533                 /* anon gid */
 534                 err = get_int(&mesg, &an_int);
 535                 if (err) goto out;
 536                 exp.ex_anon_gid= an_int;
 537
 538                 /* fsid */
 539                 err = get_int(&mesg, &an_int);
 540                 if (err) goto out;
 541                 exp.ex_fsid = an_int;
 542
 543                 while ((len = qword_get(&mesg, buf, PAGE_SIZE)) > 0) {
 544                         if (strcmp(buf, "fsloc") == 0)
 545                                 err = fsloc_parse(&mesg, buf, &exp.ex_fslocs);
 546                         else if (strcmp(buf, "uuid") == 0) {
 547                                 /* expect a 16 byte uuid encoded as \xXXXX... */
 548                                 len = qword_get(&mesg, buf, PAGE_SIZE);
 549                                 if (len != 16)
 550                                         err  = -EINVAL;
 551                                 else {
 552                                         exp.ex_uuid =
 553                                                 kmemdup(buf, 16, GFP_KERNEL);
 554                                         if (exp.ex_uuid == NULL)
 555                                                 err = -ENOMEM;
 556                                 }
 557                         } else
 558                                 /* quietly ignore unknown words and anything
 559                                  * following. Newer user-space can try to set
 560                                  * new values, then see what the result was.
 561                                  */
 562                                 break;
 563                         if (err)
 564                                 goto out;
 565                 }
 566
 567                 err = check_export(nd.dentry->d_inode, exp.ex_flags,
 568                                    exp.ex_uuid);
 569                 if (err) goto out;
 570         }
 571
 572         expp = svc_export_lookup(&exp);
 573         if (expp)
 574                 expp = svc_export_update(&exp, expp);
 575         else
 576                 err = -ENOMEM;
 577         cache_flush();
 578         if (expp == NULL)
 579                 err = -ENOMEM;
 580         else
 581                 exp_put(expp);
 582  out:
 583         nfsd4_fslocs_free(&exp.ex_fslocs);
 584         kfree(exp.ex_uuid);
 585         kfree(exp.ex_path);
 586         if (nd.dentry)
 587                 path_release(&nd);
 588  out_no_path:
 589         if (dom)
 590                 auth_domain_put(dom);
 591         kfree(buf);
 592         return err;
 593 }
 594
 595 static void exp_flags(struct seq_file *m, int flag, int fsid,
 596                 uid_t anonu, uid_t anong, struct nfsd4_fs_locations *fslocs);
 597
 598 static int svc_export_show(struct seq_file *m,
 599                            struct cache_detail *cd,
 600                            struct cache_head *h)
 601 {
 602         struct svc_export *exp ;
 603
 604         if (h ==NULL) {
 605                 seq_puts(m, "#path domain(flags)\n");
 606                 return 0;
 607         }
 608         exp = container_of(h, struct svc_export, h);
 609         seq_path(m, exp->ex_mnt, exp->ex_dentry, " \t\n\\");
 610         seq_putc(m, '\t');
 611         seq_escape(m, exp->ex_client->name, " \t\n\\");
 612         seq_putc(m, '(');
 613         if (test_bit(CACHE_VALID, &h->flags) &&
 614             !test_bit(CACHE_NEGATIVE, &h->flags)) {
 615                 exp_flags(m, exp->ex_flags, exp->ex_fsid,
 616                           exp->ex_anon_uid, exp->ex_anon_gid, &exp->ex_fslocs);
 617                 if (exp->ex_uuid) {
 618                         int i;
 619                         seq_puts(m, ",uuid=");
 620                         for (i=0; i<16; i++) {
 621                                 if ((i&3) == 0 && i)
 622                                         seq_putc(m, ':');
 623                                 seq_printf(m, "%02x", exp->ex_uuid[i]);
 624                         }
 625                 }
 626         }
 627         seq_puts(m, ")\n");
 628         return 0;
 629 }
 630 static int svc_export_match(struct cache_head *a, struct cache_head *b)
 631 {
 632         struct svc_export *orig = container_of(a, struct svc_export, h);
 633         struct svc_export *new = container_of(b, struct svc_export, h);
 634         return orig->ex_client == new->ex_client &&
 635                 orig->ex_dentry == new->ex_dentry &&
 636                 orig->ex_mnt == new->ex_mnt;
 637 }
 638
 639 static void svc_export_init(struct cache_head *cnew, struct cache_head *citem)
 640 {
 641         struct svc_export *new = container_of(cnew, struct svc_export, h);
 642         struct svc_export *item = container_of(citem, struct svc_export, h);
 643
 644         kref_get(&item->ex_client->ref);
 645         new->ex_client = item->ex_client;
 646         new->ex_dentry = dget(item->ex_dentry);
 647         new->ex_mnt = mntget(item->ex_mnt);
 648         new->ex_path = NULL;
 649         new->ex_fslocs.locations = NULL;
 650         new->ex_fslocs.locations_count = 0;
 651         new->ex_fslocs.migrated = 0;
 652 }
 653
 654 static void export_update(struct cache_head *cnew, struct cache_head *citem)
 655 {
 656         struct svc_export *new = container_of(cnew, struct svc_export, h);
 657         struct svc_export *item = container_of(citem, struct svc_export, h);
 658
 659         new->ex_flags = item->ex_flags;
 660         new->ex_anon_uid = item->ex_anon_uid;
 661         new->ex_anon_gid = item->ex_anon_gid;
 662         new->ex_fsid = item->ex_fsid;
 663         new->ex_uuid = item->ex_uuid;
 664         item->ex_uuid = NULL;
 665         new->ex_path = item->ex_path;
 666         item->ex_path = NULL;
 667         new->ex_fslocs.locations = item->ex_fslocs.locations;
 668         item->ex_fslocs.locations = NULL;
 669         new->ex_fslocs.locations_count = item->ex_fslocs.locations_count;
 670         item->ex_fslocs.locations_count = 0;
 671         new->ex_fslocs.migrated = item->ex_fslocs.migrated;
 672         item->ex_fslocs.migrated = 0;
 673 }
 674
 675 static struct cache_head *svc_export_alloc(void)
 676 {
 677         struct svc_export *i = kmalloc(sizeof(*i), GFP_KERNEL);
 678         if (i)
 679                 return &i->h;
 680         else
 681                 return NULL;
 682 }
 683
 684 struct cache_detail svc_export_cache = {
 685         .owner          = THIS_MODULE,
 686         .hash_size      = EXPORT_HASHMAX,
 687         .hash_table     = export_table,
 688         .name           = "nfsd.export",
 689         .cache_put      = svc_export_put,
 690         .cache_request  = svc_export_request,
 691         .cache_parse    = svc_export_parse,
 692         .cache_show     = svc_export_show,
 693         .match          = svc_export_match,
 694         .init           = svc_export_init,
 695         .update         = export_update,
 696         .alloc          = svc_export_alloc,
 697 };
 698
 699 static struct svc_export *
 700 svc_export_lookup(struct svc_export *exp)
 701 {
 702         struct cache_head *ch;
 703         int hash;
 704         hash = hash_ptr(exp->ex_client, EXPORT_HASHBITS);
 705         hash ^= hash_ptr(exp->ex_dentry, EXPORT_HASHBITS);
 706         hash ^= hash_ptr(exp->ex_mnt, EXPORT_HASHBITS);
 707
 708         ch = sunrpc_cache_lookup(&svc_export_cache, &exp->h,
 709                                  hash);
 710         if (ch)
 711                 return container_of(ch, struct svc_export, h);
 712         else
 713                 return NULL;
 714 }
 715
 716 static struct svc_export *
 717 svc_export_update(struct svc_export *new, struct svc_export *old)
 718 {
 719         struct cache_head *ch;
 720         int hash;
 721         hash = hash_ptr(old->ex_client, EXPORT_HASHBITS);
 722         hash ^= hash_ptr(old->ex_dentry, EXPORT_HASHBITS);
 723         hash ^= hash_ptr(old->ex_mnt, EXPORT_HASHBITS);
 724
 725         ch = sunrpc_cache_update(&svc_export_cache, &new->h,
 726                                  &old->h,
 727                                  hash);
 728         if (ch)
 729                 return container_of(ch, struct svc_export, h);
 730         else
 731                 return NULL;
 732 }
 733
 734
 735 static struct svc_expkey *
 736 exp_find_key(svc_client *clp, int fsid_type, u32 *fsidv, struct cache_req *reqp)
 737 {
 738         struct svc_expkey key, *ek;
 739         int err;
 740
 741         if (!clp)
 742                 return NULL;
 743
 744         key.ek_client = clp;
 745         key.ek_fsidtype = fsid_type;
 746         memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
 747
 748         ek = svc_expkey_lookup(&key);
 749         if (ek != NULL)
 750                 if ((err = cache_check(&svc_expkey_cache, &ek->h, reqp)))
 751                         ek = ERR_PTR(err);
 752         return ek;
 753 }
 754
 755 static int exp_set_key(svc_client *clp, int fsid_type, u32 *fsidv,
 756                        struct svc_export *exp)
 757 {
 758         struct svc_expkey key, *ek;
 759
 760         key.ek_client = clp;
 761         key.ek_fsidtype = fsid_type;
 762         memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
 763         key.ek_mnt = exp->ex_mnt;
 764         key.ek_dentry = exp->ex_dentry;
 765         key.h.expiry_time = NEVER;
 766         key.h.flags = 0;
 767
 768         ek = svc_expkey_lookup(&key);
 769         if (ek)
 770                 ek = svc_expkey_update(&key,ek);
 771         if (ek) {
 772                 cache_put(&ek->h, &svc_expkey_cache);
 773                 return 0;
 774         }
 775         return -ENOMEM;
 776 }
 777
 778 /*
 779  * Find the client's export entry matching xdev/xino.
 780  */
 781 static inline struct svc_expkey *
 782 exp_get_key(svc_client *clp, dev_t dev, ino_t ino)
 783 {
 784         u32 fsidv[3];
 785
 786         if (old_valid_dev(dev)) {
 787                 mk_fsid(FSID_DEV, fsidv, dev, ino, 0, NULL);
 788                 return exp_find_key(clp, FSID_DEV, fsidv, NULL);
 789         }
 790         mk_fsid(FSID_ENCODE_DEV, fsidv, dev, ino, 0, NULL);
 791         return exp_find_key(clp, FSID_ENCODE_DEV, fsidv, NULL);
 792 }
 793
 794 /*
 795  * Find the client's export entry matching fsid
 796  */
 797 static inline struct svc_expkey *
 798 exp_get_fsid_key(svc_client *clp, int fsid)
 799 {
 800         u32 fsidv[2];
 801
 802         mk_fsid(FSID_NUM, fsidv, 0, 0, fsid, NULL);
 803
 804         return exp_find_key(clp, FSID_NUM, fsidv, NULL);
 805 }
 806
 807 svc_export *
 808 exp_get_by_name(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry,
 809                 struct cache_req *reqp)
 810 {
 811         struct svc_export *exp, key;
 812
 813         if (!clp)
 814                 return NULL;
 815
 816         key.ex_client = clp;
 817         key.ex_mnt = mnt;
 818         key.ex_dentry = dentry;
 819
 820         exp = svc_export_lookup(&key);
 821         if (exp != NULL)  {
 822                 int err;
 823
 824                 err = cache_check(&svc_export_cache, &exp->h, reqp);
 825                 switch (err) {
 826                 case 0: break;
 827                 case -EAGAIN:
 828                 case -ETIMEDOUT:
 829                         exp = ERR_PTR(err);
 830                         break;
 831                 default:
 832                         exp = NULL;
 833                 }
 834         }
 835
 836         return exp;
 837 }
 838
 839 /*
 840  * Find the export entry for a given dentry.
 841  */
 842 struct svc_export *
 843 exp_parent(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry,
 844            struct cache_req *reqp)
 845 {
 846         svc_export *exp;
 847
 848         dget(dentry);
 849         exp = exp_get_by_name(clp, mnt, dentry, reqp);
 850
 851         while (exp == NULL && !IS_ROOT(dentry)) {
 852                 struct dentry *parent;
 853
 854                 parent = dget_parent(dentry);
 855                 dput(dentry);
 856                 dentry = parent;
 857                 exp = exp_get_by_name(clp, mnt, dentry, reqp);
 858         }
 859         dput(dentry);
 860         return exp;
 861 }
 862
 863 /*
 864  * Hashtable locking. Write locks are placed only by user processes
 865  * wanting to modify export information.
 866  * Write locking only done in this file.  Read locking
 867  * needed externally.
 868  */
 869
 870 static DECLARE_RWSEM(hash_sem);
 871
 872 void
 873 exp_readlock(void)
 874 {
 875         down_read(&hash_sem);
 876 }
 877
 878 static inline void
 879 exp_writelock(void)
 880 {
 881         down_write(&hash_sem);
 882 }
 883
 884 void
 885 exp_readunlock(void)
 886 {
 887         up_read(&hash_sem);
 888 }
 889
 890 static inline void
 891 exp_writeunlock(void)
 892 {
 893         up_write(&hash_sem);
 894 }
 895
 896 static void exp_fsid_unhash(struct svc_export *exp)
 897 {
 898         struct svc_expkey *ek;
 899
 900         if ((exp->ex_flags & NFSEXP_FSID) == 0)
 901                 return;
 902
 903         ek = exp_get_fsid_key(exp->ex_client, exp->ex_fsid);
 904         if (ek && !IS_ERR(ek)) {
 905                 ek->h.expiry_time = get_seconds()-1;
 906                 cache_put(&ek->h, &svc_expkey_cache);
 907         }
 908         svc_expkey_cache.nextcheck = get_seconds();
 909 }
 910
 911 static int exp_fsid_hash(svc_client *clp, struct svc_export *exp)
 912 {
 913         u32 fsid[2];
 914
 915         if ((exp->ex_flags & NFSEXP_FSID) == 0)
 916                 return 0;
 917
 918         mk_fsid(FSID_NUM, fsid, 0, 0, exp->ex_fsid, NULL);
 919         return exp_set_key(clp, FSID_NUM, fsid, exp);
 920 }
 921
 922 static int exp_hash(struct auth_domain *clp, struct svc_export *exp)
 923 {
 924         u32 fsid[2];
 925         struct inode *inode = exp->ex_dentry->d_inode;
 926         dev_t dev = inode->i_sb->s_dev;
 927
 928         if (old_valid_dev(dev)) {
 929                 mk_fsid(FSID_DEV, fsid, dev, inode->i_ino, 0, NULL);
 930                 return exp_set_key(clp, FSID_DEV, fsid, exp);
 931         }
 932         mk_fsid(FSID_ENCODE_DEV, fsid, dev, inode->i_ino, 0, NULL);
 933         return exp_set_key(clp, FSID_ENCODE_DEV, fsid, exp);
 934 }
 935
 936 static void exp_unhash(struct svc_export *exp)
 937 {
 938         struct svc_expkey *ek;
 939         struct inode *inode = exp->ex_dentry->d_inode;
 940
 941         ek = exp_get_key(exp->ex_client, inode->i_sb->s_dev, inode->i_ino);
 942         if (ek && !IS_ERR(ek)) {
 943                 ek->h.expiry_time = get_seconds()-1;
 944                 cache_put(&ek->h, &svc_expkey_cache);
 945         }
 946         svc_expkey_cache.nextcheck = get_seconds();
 947 }
 948
 949 /*
 950  * Export a file system.
 951  */
 952 int
 953 exp_export(struct nfsctl_export *nxp)
 954 {
 955         svc_client      *clp;
 956         struct svc_export       *exp = NULL;
 957         struct svc_export       new;
 958         struct svc_expkey       *fsid_key = NULL;
 959         struct nameidata nd;
 960         int             err;
 961
 962         /* Consistency check */
 963         err = -EINVAL;
 964         if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) ||
 965             !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX))
 966                 goto out;
 967
 968         dprintk("exp_export called for %s:%s (%x/%ld fl %x).\n",
 969                         nxp->ex_client, nxp->ex_path,
 970                         (unsigned)nxp->ex_dev, (long)nxp->ex_ino,
 971                         nxp->ex_flags);
 972
 973         /* Try to lock the export table for update */
 974         exp_writelock();
 975
 976         /* Look up client info */
 977         if (!(clp = auth_domain_find(nxp->ex_client)))
 978                 goto out_unlock;
 979
 980
 981         /* Look up the dentry */
 982         err = path_lookup(nxp->ex_path, 0, &nd);
 983         if (err)
 984                 goto out_unlock;
 985         err = -EINVAL;
 986
 987         exp = exp_get_by_name(clp, nd.mnt, nd.dentry, NULL);
 988
 989         memset(&new, 0, sizeof(new));
 990
 991         /* must make sure there won't be an ex_fsid clash */
 992         if ((nxp->ex_flags & NFSEXP_FSID) &&
 993             (fsid_key = exp_get_fsid_key(clp, nxp->ex_dev)) &&
 994             !IS_ERR(fsid_key) &&
 995             fsid_key->ek_mnt &&
 996             (fsid_key->ek_mnt != nd.mnt || fsid_key->ek_dentry != nd.dentry) )
 997                 goto finish;
 998
 999         if (exp) {
1000                 /* just a flags/id/fsid update */
1001
1002                 exp_fsid_unhash(exp);
1003                 exp->ex_flags    = nxp->ex_flags;
1004                 exp->ex_anon_uid = nxp->ex_anon_uid;
1005                 exp->ex_anon_gid = nxp->ex_anon_gid;
1006                 exp->ex_fsid     = nxp->ex_dev;
1007
1008                 err = exp_fsid_hash(clp, exp);
1009                 goto finish;
1010         }
1011
1012         err = check_export(nd.dentry->d_inode, nxp->ex_flags, NULL);
1013         if (err) goto finish;
1014
1015         err = -ENOMEM;
1016
1017         dprintk("nfsd: creating export entry %p for client %p\n", exp, clp);
1018
1019         new.h.expiry_time = NEVER;
1020         new.h.flags = 0;
1021         new.ex_path = kstrdup(nxp->ex_path, GFP_KERNEL);
1022         if (!new.ex_path)
1023                 goto finish;
1024         new.ex_client = clp;
1025         new.ex_mnt = nd.mnt;
1026         new.ex_dentry = nd.dentry;
1027         new.ex_flags = nxp->ex_flags;
1028         new.ex_anon_uid = nxp->ex_anon_uid;
1029         new.ex_anon_gid = nxp->ex_anon_gid;
1030         new.ex_fsid = nxp->ex_dev;
1031
1032         exp = svc_export_lookup(&new);
1033         if (exp)
1034                 exp = svc_export_update(&new, exp);
1035
1036         if (!exp)
1037                 goto finish;
1038
1039         if (exp_hash(clp, exp) ||
1040             exp_fsid_hash(clp, exp)) {
1041                 /* failed to create at least one index */
1042                 exp_do_unexport(exp);
1043                 cache_flush();
1044         } else
1045                 err = 0;
1046 finish:
1047         if (new.ex_path)
1048                 kfree(new.ex_path);
1049         if (exp)
1050                 exp_put(exp);
1051         if (fsid_key && !IS_ERR(fsid_key))
1052                 cache_put(&fsid_key->h, &svc_expkey_cache);
1053         if (clp)
1054                 auth_domain_put(clp);
1055         path_release(&nd);
1056 out_unlock:
1057         exp_writeunlock();
1058 out:
1059         return err;
1060 }
1061
1062 /*
1063  * Unexport a file system. The export entry has already
1064  * been removed from the client's list of exported fs's.
1065  */
1066 static void
1067 exp_do_unexport(svc_export *unexp)
1068 {
1069         unexp->h.expiry_time = get_seconds()-1;
1070         svc_export_cache.nextcheck = get_seconds();
1071         exp_unhash(unexp);
1072         exp_fsid_unhash(unexp);
1073 }
1074
1075
1076 /*
1077  * unexport syscall.
1078  */
1079 int
1080 exp_unexport(struct nfsctl_export *nxp)
1081 {
1082         struct auth_domain *dom;
1083         svc_export *exp;
1084         struct nameidata nd;
1085         int             err;
1086
1087         /* Consistency check */
1088         if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) ||
1089             !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX))
1090                 return -EINVAL;
1091
1092         exp_writelock();
1093
1094         err = -EINVAL;
1095         dom = auth_domain_find(nxp->ex_client);
1096         if (!dom) {
1097                 dprintk("nfsd: unexport couldn't find %s\n", nxp->ex_client);
1098                 goto out_unlock;
1099         }
1100
1101         err = path_lookup(nxp->ex_path, 0, &nd);
1102         if (err)
1103                 goto out_domain;
1104
1105         err = -EINVAL;
1106         exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL);
1107         path_release(&nd);
1108         if (!exp)
1109                 goto out_domain;
1110
1111         exp_do_unexport(exp);
1112         exp_put(exp);
1113         err = 0;
1114
1115 out_domain:
1116         auth_domain_put(dom);
1117         cache_flush();
1118 out_unlock:
1119         exp_writeunlock();
1120         return err;
1121 }
1122
1123 /*
1124  * Obtain the root fh on behalf of a client.
1125  * This could be done in user space, but I feel that it adds some safety
1126  * since its harder to fool a kernel module than a user space program.
1127  */
1128 int
1129 exp_rootfh(svc_client *clp, char *path, struct knfsd_fh *f, int maxsize)
1130 {
1131         struct svc_export       *exp;
1132         struct nameidata        nd;
1133         struct inode            *inode;
1134         struct svc_fh           fh;
1135         int                     err;
1136
1137         err = -EPERM;
1138         /* NB: we probably ought to check that it's NUL-terminated */
1139         if (path_lookup(path, 0, &nd)) {
1140                 printk("nfsd: exp_rootfh path not found %s", path);
1141                 return err;
1142         }
1143         inode = nd.dentry->d_inode;
1144
1145         dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n",
1146                  path, nd.dentry, clp->name,
1147                  inode->i_sb->s_id, inode->i_ino);
1148         exp = exp_parent(clp, nd.mnt, nd.dentry, NULL);
1149         if (IS_ERR(exp)) {
1150                 err = PTR_ERR(exp);
1151                 goto out;
1152         }
1153         if (!exp) {
1154                 dprintk("nfsd: exp_rootfh export not found.\n");
1155                 goto out;
1156         }
1157
1158         /*
1159          * fh must be initialized before calling fh_compose
1160          */
1161         fh_init(&fh, maxsize);
1162         if (fh_compose(&fh, exp, nd.dentry, NULL))
1163                 err = -EINVAL;
1164         else
1165                 err = 0;
1166         memcpy(f, &fh.fh_handle, sizeof(struct knfsd_fh));
1167         fh_put(&fh);
1168         exp_put(exp);
1169 out:
1170         path_release(&nd);
1171         return err;
1172 }
1173
1174 struct svc_export *
1175 exp_find(struct auth_domain *clp, int fsid_type, u32 *fsidv,
1176          struct cache_req *reqp)
1177 {
1178         struct svc_export *exp;
1179         struct svc_expkey *ek = exp_find_key(clp, fsid_type, fsidv, reqp);
1180         if (!ek || IS_ERR(ek))
1181                 return ERR_PTR(PTR_ERR(ek));
1182
1183         exp = exp_get_by_name(clp, ek->ek_mnt, ek->ek_dentry, reqp);
1184         cache_put(&ek->h, &svc_expkey_cache);
1185
1186         if (!exp || IS_ERR(exp))
1187                 return ERR_PTR(PTR_ERR(exp));
1188         return exp;
1189 }
1190
1191
1192 /*
1193  * Called when we need the filehandle for the root of the pseudofs,
1194  * for a given NFSv4 client.   The root is defined to be the
1195  * export point with fsid==0
1196  */
1197 __be32
1198 exp_pseudoroot(struct auth_domain *clp, struct svc_fh *fhp,
1199                struct cache_req *creq)
1200 {
1201         struct svc_export *exp;
1202         __be32 rv;
1203         u32 fsidv[2];
1204
1205         mk_fsid(FSID_NUM, fsidv, 0, 0, 0, NULL);
1206
1207         exp = exp_find(clp, FSID_NUM, fsidv, creq);
1208         if (IS_ERR(exp))
1209                 return nfserrno(PTR_ERR(exp));
1210         if (exp == NULL)
1211                 return nfserr_perm;
1212         rv = fh_compose(fhp, exp, exp->ex_dentry, NULL);
1213         exp_put(exp);
1214         return rv;
1215 }
1216
1217 /* Iterator */
1218
1219 static void *e_start(struct seq_file *m, loff_t *pos)
1220         __acquires(svc_export_cache.hash_lock)
1221 {
1222         loff_t n = *pos;
1223         unsigned hash, export;
1224         struct cache_head *ch;
1225
1226         exp_readlock();
1227         read_lock(&svc_export_cache.hash_lock);
1228         if (!n--)
1229                 return SEQ_START_TOKEN;
1230         hash = n >> 32;
1231         export = n & ((1LL<<32) - 1);
1232
1233
1234         for (ch=export_table[hash]; ch; ch=ch->next)
1235                 if (!export--)
1236                         return ch;
1237         n &= ~((1LL<<32) - 1);
1238         do {
1239                 hash++;
1240                 n += 1LL<<32;
1241         } while(hash < EXPORT_HASHMAX && export_table[hash]==NULL);
1242         if (hash >= EXPORT_HASHMAX)
1243                 return NULL;
1244         *pos = n+1;
1245         return export_table[hash];
1246 }
1247
1248 static void *e_next(struct seq_file *m, void *p, loff_t *pos)
1249 {
1250         struct cache_head *ch = p;
1251         int hash = (*pos >> 32);
1252
1253         if (p == SEQ_START_TOKEN)
1254                 hash = 0;
1255         else if (ch->next == NULL) {
1256                 hash++;
1257                 *pos += 1LL<<32;
1258         } else {
1259                 ++*pos;
1260                 return ch->next;
1261         }
1262         *pos &= ~((1LL<<32) - 1);
1263         while (hash < EXPORT_HASHMAX && export_table[hash] == NULL) {
1264                 hash++;
1265                 *pos += 1LL<<32;
1266         }
1267         if (hash >= EXPORT_HASHMAX)
1268                 return NULL;
1269         ++*pos;
1270         return export_table[hash];
1271 }
1272
1273 static void e_stop(struct seq_file *m, void *p)
1274         __releases(svc_export_cache.hash_lock)
1275 {
1276         read_unlock(&svc_export_cache.hash_lock);
1277         exp_readunlock();
1278 }
1279
1280 static struct flags {
1281         int flag;
1282         char *name[2];
1283 } expflags[] = {
1284         { NFSEXP_READONLY, {"ro", "rw"}},
1285         { NFSEXP_INSECURE_PORT, {"insecure", ""}},
1286         { NFSEXP_ROOTSQUASH, {"root_squash", "no_root_squash"}},
1287         { NFSEXP_ALLSQUASH, {"all_squash", ""}},
1288         { NFSEXP_ASYNC, {"async", "sync"}},
1289         { NFSEXP_GATHERED_WRITES, {"wdelay", "no_wdelay"}},
1290         { NFSEXP_NOHIDE, {"nohide", ""}},
1291         { NFSEXP_CROSSMOUNT, {"crossmnt", ""}},
1292         { NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}},
1293         { NFSEXP_NOAUTHNLM, {"insecure_locks", ""}},
1294 #ifdef MSNFS
1295         { NFSEXP_MSNFS, {"msnfs", ""}},
1296 #endif
1297         { 0, {"", ""}}
1298 };
1299
1300 static void exp_flags(struct seq_file *m, int flag, int fsid,
1301                 uid_t anonu, uid_t anong, struct nfsd4_fs_locations *fsloc)
1302 {
1303         int first = 0;
1304         struct flags *flg;
1305
1306         for (flg = expflags; flg->flag; flg++) {
1307                 int state = (flg->flag & flag)?0:1;
1308                 if (*flg->name[state])
1309                         seq_printf(m, "%s%s", first++?",":"", flg->name[state]);
1310         }
1311         if (flag & NFSEXP_FSID)
1312                 seq_printf(m, "%sfsid=%d", first++?",":"", fsid);
1313         if (anonu != (uid_t)-2 && anonu != (0x10000-2))
1314                 seq_printf(m, "%sanonuid=%d", first++?",":"", anonu);
1315         if (anong != (gid_t)-2 && anong != (0x10000-2))
1316                 seq_printf(m, "%sanongid=%d", first++?",":"", anong);
1317         if (fsloc && fsloc->locations_count > 0) {
1318                 char *loctype = (fsloc->migrated) ? "refer" : "replicas";
1319                 int i;
1320
1321                 seq_printf(m, "%s%s=", first++?",":"", loctype);
1322                 seq_escape(m, fsloc->locations[0].path, ",;@ \t\n\\");
1323                 seq_putc(m, '@');
1324                 seq_escape(m, fsloc->locations[0].hosts, ",;@ \t\n\\");
1325                 for (i = 1; i < fsloc->locations_count; i++) {
1326                         seq_putc(m, ';');
1327                         seq_escape(m, fsloc->locations[i].path, ",;@ \t\n\\");
1328                         seq_putc(m, '@');
1329                         seq_escape(m, fsloc->locations[i].hosts, ",;@ \t\n\\");
1330                 }
1331         }
1332 }
1333
1334 static int e_show(struct seq_file *m, void *p)
1335 {
1336         struct cache_head *cp = p;
1337         struct svc_export *exp = container_of(cp, struct svc_export, h);
1338
1339         if (p == SEQ_START_TOKEN) {
1340                 seq_puts(m, "# Version 1.1\n");
1341                 seq_puts(m, "# Path Client(Flags) # IPs\n");
1342                 return 0;
1343         }
1344
1345         cache_get(&exp->h);
1346         if (cache_check(&svc_export_cache, &exp->h, NULL))
1347                 return 0;
1348         cache_put(&exp->h, &svc_export_cache);
1349         return svc_export_show(m, &svc_export_cache, cp);
1350 }
1351
1352 struct seq_operations nfs_exports_op = {
1353         .start  = e_start,
1354         .next   = e_next,
1355         .stop   = e_stop,
1356         .show   = e_show,
1357 };
1358
1359 /*
1360  * Add or modify a client.
1361  * Change requests may involve the list of host addresses. The list of
1362  * exports and possibly existing uid maps are left untouched.
1363  */
1364 int
1365 exp_addclient(struct nfsctl_client *ncp)
1366 {
1367         struct auth_domain      *dom;
1368         int                     i, err;
1369
1370         /* First, consistency check. */
1371         err = -EINVAL;
1372         if (! exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX))
1373                 goto out;
1374         if (ncp->cl_naddr > NFSCLNT_ADDRMAX)
1375                 goto out;
1376
1377         /* Lock the hashtable */
1378         exp_writelock();
1379
1380         dom = unix_domain_find(ncp->cl_ident);
1381
1382         err = -ENOMEM;
1383         if (!dom)
1384                 goto out_unlock;
1385
1386         /* Insert client into hashtable. */
1387         for (i = 0; i < ncp->cl_naddr; i++)
1388                 auth_unix_add_addr(ncp->cl_addrlist[i], dom);
1389
1390         auth_unix_forget_old(dom);
1391         auth_domain_put(dom);
1392
1393         err = 0;
1394
1395 out_unlock:
1396         exp_writeunlock();
1397 out:
1398         return err;
1399 }
1400
1401 /*
1402  * Delete a client given an identifier.
1403  */
1404 int
1405 exp_delclient(struct nfsctl_client *ncp)
1406 {
1407         int             err;
1408         struct auth_domain *dom;
1409
1410         err = -EINVAL;
1411         if (!exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX))
1412                 goto out;
1413
1414         /* Lock the hashtable */
1415         exp_writelock();
1416
1417         dom = auth_domain_find(ncp->cl_ident);
1418         /* just make sure that no addresses work
1419          * and that it will expire soon
1420          */
1421         if (dom) {
1422                 err = auth_unix_forget_old(dom);
1423                 auth_domain_put(dom);
1424         }
1425
1426         exp_writeunlock();
1427 out:
1428         return err;
1429 }
1430
1431 /*
1432  * Verify that string is non-empty and does not exceed max length.
1433  */
1434 static int
1435 exp_verify_string(char *cp, int max)
1436 {
1437         int     i;
1438
1439         for (i = 0; i < max; i++)
1440                 if (!cp[i])
1441                         return i;
1442         cp[i] = 0;
1443         printk(KERN_NOTICE "nfsd: couldn't validate string %s\n", cp);
1444         return 0;
1445 }
1446
1447 /*
1448  * Initialize the exports module.
1449  */
1450 void
1451 nfsd_export_init(void)
1452 {
1453         dprintk("nfsd: initializing export module.\n");
1454
1455         cache_register(&svc_export_cache);
1456         cache_register(&svc_expkey_cache);
1457
1458 }
1459
1460 /*
1461  * Flush exports table - called when last nfsd thread is killed
1462  */
1463 void
1464 nfsd_export_flush(void)
1465 {
1466         exp_writelock();
1467         cache_purge(&svc_expkey_cache);
1468         cache_purge(&svc_export_cache);
1469         exp_writeunlock();
1470 }
1471
1472 /*
1473  * Shutdown the exports module.
1474  */
1475 void
1476 nfsd_export_shutdown(void)
1477 {
1478
1479         dprintk("nfsd: shutting down export module.\n");
1480
1481         exp_writelock();
1482
1483         if (cache_unregister(&svc_expkey_cache))
1484                 printk(KERN_ERR "nfsd: failed to unregister expkey cache\n");
1485         if (cache_unregister(&svc_export_cache))
1486                 printk(KERN_ERR "nfsd: failed to unregister export cache\n");
1487         svcauth_unix_purge();
1488
1489         exp_writeunlock();
1490         dprintk("nfsd: export shutdown complete.\n");
1491 }