fs/afs/super.c

   1 /* AFS superblock handling
   2  *
   3  * Copyright (c) 2002, 2007, 2018 Red Hat, Inc. All rights reserved.
   4  *
   5  * This software may be freely redistributed under the terms of the
   6  * GNU General Public License.
   7  *
   8  * You should have received a copy of the GNU General Public License
   9  * along with this program; if not, write to the Free Software
  10  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  11  *
  12  * Authors: David Howells <dhowells@redhat.com>
  13  *          David Woodhouse <dwmw2@infradead.org>
  14  *
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/mount.h>
  20 #include <linux/init.h>
  21 #include <linux/slab.h>
  22 #include <linux/fs.h>
  23 #include <linux/pagemap.h>
  24 #include <linux/fs_parser.h>
  25 #include <linux/statfs.h>
  26 #include <linux/sched.h>
  27 #include <linux/nsproxy.h>
  28 #include <linux/magic.h>
  29 #include <net/net_namespace.h>
  30 #include "internal.h"
  31
  32 static void afs_i_init_once(void *foo);
  33 static void afs_kill_super(struct super_block *sb);
  34 static struct inode *afs_alloc_inode(struct super_block *sb);
  35 static void afs_destroy_inode(struct inode *inode);
  36 static void afs_free_inode(struct inode *inode);
  37 static int afs_statfs(struct dentry *dentry, struct kstatfs *buf);
  38 static int afs_show_devname(struct seq_file *m, struct dentry *root);
  39 static int afs_show_options(struct seq_file *m, struct dentry *root);
  40 static int afs_init_fs_context(struct fs_context *fc);
  41 static const struct fs_parameter_spec afs_fs_parameters[];
  42
  43 struct file_system_type afs_fs_type = {
  44         .owner                  = THIS_MODULE,
  45         .name                   = "afs",
  46         .init_fs_context        = afs_init_fs_context,
  47         .parameters             = afs_fs_parameters,
  48         .kill_sb                = afs_kill_super,
  49         .fs_flags               = FS_RENAME_DOES_D_MOVE,
  50 };
  51 MODULE_ALIAS_FS("afs");
  52
  53 int afs_net_id;
  54
  55 static const struct super_operations afs_super_ops = {
  56         .statfs         = afs_statfs,
  57         .alloc_inode    = afs_alloc_inode,
  58         .drop_inode     = afs_drop_inode,
  59         .destroy_inode  = afs_destroy_inode,
  60         .free_inode     = afs_free_inode,
  61         .evict_inode    = afs_evict_inode,
  62         .show_devname   = afs_show_devname,
  63         .show_options   = afs_show_options,
  64 };
  65
  66 static struct kmem_cache *afs_inode_cachep;
  67 static atomic_t afs_count_active_inodes;
  68
  69 enum afs_param {
  70         Opt_autocell,
  71         Opt_dyn,
  72         Opt_flock,
  73         Opt_source,
  74 };
  75
  76 static const struct constant_table afs_param_flock[] = {
  77         {"local",       afs_flock_mode_local },
  78         {"openafs",     afs_flock_mode_openafs },
  79         {"strict",      afs_flock_mode_strict },
  80         {"write",       afs_flock_mode_write },
  81         {}
  82 };
  83
  84 static const struct fs_parameter_spec afs_fs_parameters[] = {
  85         fsparam_flag  ("autocell",      Opt_autocell),
  86         fsparam_flag  ("dyn",           Opt_dyn),
  87         fsparam_enum  ("flock",         Opt_flock, afs_param_flock),
  88         fsparam_string("source",        Opt_source),
  89         {}
  90 };
  91
  92 /*
  93  * initialise the filesystem
  94  */
  95 int __init afs_fs_init(void)
  96 {
  97         int ret;
  98
  99         _enter("");
 100
 101         /* create ourselves an inode cache */
 102         atomic_set(&afs_count_active_inodes, 0);
 103
 104         ret = -ENOMEM;
 105         afs_inode_cachep = kmem_cache_create("afs_inode_cache",
 106                                              sizeof(struct afs_vnode),
 107                                              0,
 108                                              SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT,
 109                                              afs_i_init_once);
 110         if (!afs_inode_cachep) {
 111                 printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
 112                 return ret;
 113         }
 114
 115         /* now export our filesystem to lesser mortals */
 116         ret = register_filesystem(&afs_fs_type);
 117         if (ret < 0) {
 118                 kmem_cache_destroy(afs_inode_cachep);
 119                 _leave(" = %d", ret);
 120                 return ret;
 121         }
 122
 123         _leave(" = 0");
 124         return 0;
 125 }
 126
 127 /*
 128  * clean up the filesystem
 129  */
 130 void afs_fs_exit(void)
 131 {
 132         _enter("");
 133
 134         afs_mntpt_kill_timer();
 135         unregister_filesystem(&afs_fs_type);
 136
 137         if (atomic_read(&afs_count_active_inodes) != 0) {
 138                 printk("kAFS: %d active inode objects still present\n",
 139                        atomic_read(&afs_count_active_inodes));
 140                 BUG();
 141         }
 142
 143         /*
 144          * Make sure all delayed rcu free inodes are flushed before we
 145          * destroy cache.
 146          */
 147         rcu_barrier();
 148         kmem_cache_destroy(afs_inode_cachep);
 149         _leave("");
 150 }
 151
 152 /*
 153  * Display the mount device name in /proc/mounts.
 154  */
 155 static int afs_show_devname(struct seq_file *m, struct dentry *root)
 156 {
 157         struct afs_super_info *as = AFS_FS_S(root->d_sb);
 158         struct afs_volume *volume = as->volume;
 159         struct afs_cell *cell = as->cell;
 160         const char *suf = "";
 161         char pref = '%';
 162
 163         if (as->dyn_root) {
 164                 seq_puts(m, "none");
 165                 return 0;
 166         }
 167
 168         switch (volume->type) {
 169         case AFSVL_RWVOL:
 170                 break;
 171         case AFSVL_ROVOL:
 172                 pref = '#';
 173                 if (volume->type_force)
 174                         suf = ".readonly";
 175                 break;
 176         case AFSVL_BACKVOL:
 177                 pref = '#';
 178                 suf = ".backup";
 179                 break;
 180         }
 181
 182         seq_printf(m, "%c%s:%s%s", pref, cell->name, volume->name, suf);
 183         return 0;
 184 }
 185
 186 /*
 187  * Display the mount options in /proc/mounts.
 188  */
 189 static int afs_show_options(struct seq_file *m, struct dentry *root)
 190 {
 191         struct afs_super_info *as = AFS_FS_S(root->d_sb);
 192         const char *p = NULL;
 193
 194         if (as->dyn_root)
 195                 seq_puts(m, ",dyn");
 196         if (test_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(d_inode(root))->flags))
 197                 seq_puts(m, ",autocell");
 198         switch (as->flock_mode) {
 199         case afs_flock_mode_unset:      break;
 200         case afs_flock_mode_local:      p = "local";    break;
 201         case afs_flock_mode_openafs:    p = "openafs";  break;
 202         case afs_flock_mode_strict:     p = "strict";   break;
 203         case afs_flock_mode_write:      p = "write";    break;
 204         }
 205         if (p)
 206                 seq_printf(m, ",flock=%s", p);
 207
 208         return 0;
 209 }
 210
 211 /*
 212  * Parse the source name to get cell name, volume name, volume type and R/W
 213  * selector.
 214  *
 215  * This can be one of the following:
 216  *      "%[cell:]volume[.]"             R/W volume
 217  *      "#[cell:]volume[.]"             R/O or R/W volume (R/O parent),
 218  *                                       or R/W (R/W parent) volume
 219  *      "%[cell:]volume.readonly"       R/O volume
 220  *      "#[cell:]volume.readonly"       R/O volume
 221  *      "%[cell:]volume.backup"         Backup volume
 222  *      "#[cell:]volume.backup"         Backup volume
 223  */
 224 static int afs_parse_source(struct fs_context *fc, struct fs_parameter *param)
 225 {
 226         struct afs_fs_context *ctx = fc->fs_private;
 227         struct afs_cell *cell;
 228         const char *cellname, *suffix, *name = param->string;
 229         int cellnamesz;
 230
 231         _enter(",%s", name);
 232
 233         if (fc->source)
 234                 return invalf(fc, "kAFS: Multiple sources not supported");
 235
 236         if (!name) {
 237                 printk(KERN_ERR "kAFS: no volume name specified\n");
 238                 return -EINVAL;
 239         }
 240
 241         if ((name[0] != '%' && name[0] != '#') || !name[1]) {
 242                 /* To use dynroot, we don't want to have to provide a source */
 243                 if (strcmp(name, "none") == 0) {
 244                         ctx->no_cell = true;
 245                         return 0;
 246                 }
 247                 printk(KERN_ERR "kAFS: unparsable volume name\n");
 248                 return -EINVAL;
 249         }
 250
 251         /* determine the type of volume we're looking for */
 252         if (name[0] == '%') {
 253                 ctx->type = AFSVL_RWVOL;
 254                 ctx->force = true;
 255         }
 256         name++;
 257
 258         /* split the cell name out if there is one */
 259         ctx->volname = strchr(name, ':');
 260         if (ctx->volname) {
 261                 cellname = name;
 262                 cellnamesz = ctx->volname - name;
 263                 ctx->volname++;
 264         } else {
 265                 ctx->volname = name;
 266                 cellname = NULL;
 267                 cellnamesz = 0;
 268         }
 269
 270         /* the volume type is further affected by a possible suffix */
 271         suffix = strrchr(ctx->volname, '.');
 272         if (suffix) {
 273                 if (strcmp(suffix, ".readonly") == 0) {
 274                         ctx->type = AFSVL_ROVOL;
 275                         ctx->force = true;
 276                 } else if (strcmp(suffix, ".backup") == 0) {
 277                         ctx->type = AFSVL_BACKVOL;
 278                         ctx->force = true;
 279                 } else if (suffix[1] == 0) {
 280                 } else {
 281                         suffix = NULL;
 282                 }
 283         }
 284
 285         ctx->volnamesz = suffix ?
 286                 suffix - ctx->volname : strlen(ctx->volname);
 287
 288         _debug("cell %*.*s [%p]",
 289                cellnamesz, cellnamesz, cellname ?: "", ctx->cell);
 290
 291         /* lookup the cell record */
 292         if (cellname) {
 293                 cell = afs_lookup_cell(ctx->net, cellname, cellnamesz,
 294                                        NULL, false);
 295                 if (IS_ERR(cell)) {
 296                         pr_err("kAFS: unable to lookup cell '%*.*s'\n",
 297                                cellnamesz, cellnamesz, cellname ?: "");
 298                         return PTR_ERR(cell);
 299                 }
 300                 afs_unuse_cell(ctx->net, ctx->cell, afs_cell_trace_unuse_parse);
 301                 afs_see_cell(cell, afs_cell_trace_see_source);
 302                 ctx->cell = cell;
 303         }
 304
 305         _debug("CELL:%s [%p] VOLUME:%*.*s SUFFIX:%s TYPE:%d%s",
 306                ctx->cell->name, ctx->cell,
 307                ctx->volnamesz, ctx->volnamesz, ctx->volname,
 308                suffix ?: "-", ctx->type, ctx->force ? " FORCE" : "");
 309
 310         fc->source = param->string;
 311         param->string = NULL;
 312         return 0;
 313 }
 314
 315 /*
 316  * Parse a single mount parameter.
 317  */
 318 static int afs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 319 {
 320         struct fs_parse_result result;
 321         struct afs_fs_context *ctx = fc->fs_private;
 322         int opt;
 323
 324         opt = fs_parse(fc, afs_fs_parameters, param, &result);
 325         if (opt < 0)
 326                 return opt;
 327
 328         switch (opt) {
 329         case Opt_source:
 330                 return afs_parse_source(fc, param);
 331
 332         case Opt_autocell:
 333                 ctx->autocell = true;
 334                 break;
 335
 336         case Opt_dyn:
 337                 ctx->dyn_root = true;
 338                 break;
 339
 340         case Opt_flock:
 341                 ctx->flock_mode = result.uint_32;
 342                 break;
 343
 344         default:
 345                 return -EINVAL;
 346         }
 347
 348         _leave(" = 0");
 349         return 0;
 350 }
 351
 352 /*
 353  * Validate the options, get the cell key and look up the volume.
 354  */
 355 static int afs_validate_fc(struct fs_context *fc)
 356 {
 357         struct afs_fs_context *ctx = fc->fs_private;
 358         struct afs_volume *volume;
 359         struct afs_cell *cell;
 360         struct key *key;
 361         int ret;
 362
 363         if (!ctx->dyn_root) {
 364                 if (ctx->no_cell) {
 365                         pr_warn("kAFS: Can only specify source 'none' with -o dyn\n");
 366                         return -EINVAL;
 367                 }
 368
 369                 if (!ctx->cell) {
 370                         pr_warn("kAFS: No cell specified\n");
 371                         return -EDESTADDRREQ;
 372                 }
 373
 374         reget_key:
 375                 /* We try to do the mount securely. */
 376                 key = afs_request_key(ctx->cell);
 377                 if (IS_ERR(key))
 378                         return PTR_ERR(key);
 379
 380                 ctx->key = key;
 381
 382                 if (ctx->volume) {
 383                         afs_put_volume(ctx->net, ctx->volume,
 384                                        afs_volume_trace_put_validate_fc);
 385                         ctx->volume = NULL;
 386                 }
 387
 388                 if (test_bit(AFS_CELL_FL_CHECK_ALIAS, &ctx->cell->flags)) {
 389                         ret = afs_cell_detect_alias(ctx->cell, key);
 390                         if (ret < 0)
 391                                 return ret;
 392                         if (ret == 1) {
 393                                 _debug("switch to alias");
 394                                 key_put(ctx->key);
 395                                 ctx->key = NULL;
 396                                 cell = afs_use_cell(ctx->cell->alias_of,
 397                                                     afs_cell_trace_use_fc_alias);
 398                                 afs_unuse_cell(ctx->net, ctx->cell, afs_cell_trace_unuse_fc);
 399                                 ctx->cell = cell;
 400                                 goto reget_key;
 401                         }
 402                 }
 403
 404                 volume = afs_create_volume(ctx);
 405                 if (IS_ERR(volume))
 406                         return PTR_ERR(volume);
 407
 408                 ctx->volume = volume;
 409         }
 410
 411         return 0;
 412 }
 413
 414 /*
 415  * check a superblock to see if it's the one we're looking for
 416  */
 417 static int afs_test_super(struct super_block *sb, struct fs_context *fc)
 418 {
 419         struct afs_fs_context *ctx = fc->fs_private;
 420         struct afs_super_info *as = AFS_FS_S(sb);
 421
 422         return (as->net_ns == fc->net_ns &&
 423                 as->volume &&
 424                 as->volume->vid == ctx->volume->vid &&
 425                 as->cell == ctx->cell &&
 426                 !as->dyn_root);
 427 }
 428
 429 static int afs_dynroot_test_super(struct super_block *sb, struct fs_context *fc)
 430 {
 431         struct afs_super_info *as = AFS_FS_S(sb);
 432
 433         return (as->net_ns == fc->net_ns &&
 434                 as->dyn_root);
 435 }
 436
 437 static int afs_set_super(struct super_block *sb, struct fs_context *fc)
 438 {
 439         return set_anon_super(sb, NULL);
 440 }
 441
 442 /*
 443  * fill in the superblock
 444  */
 445 static int afs_fill_super(struct super_block *sb, struct afs_fs_context *ctx)
 446 {
 447         struct afs_super_info *as = AFS_FS_S(sb);
 448         struct inode *inode = NULL;
 449         int ret;
 450
 451         _enter("");
 452
 453         /* fill in the superblock */
 454         sb->s_blocksize         = PAGE_SIZE;
 455         sb->s_blocksize_bits    = PAGE_SHIFT;
 456         sb->s_maxbytes          = MAX_LFS_FILESIZE;
 457         sb->s_magic             = AFS_FS_MAGIC;
 458         sb->s_op                = &afs_super_ops;
 459         if (!as->dyn_root)
 460                 sb->s_xattr     = afs_xattr_handlers;
 461         ret = super_setup_bdi(sb);
 462         if (ret)
 463                 return ret;
 464
 465         /* allocate the root inode and dentry */
 466         if (as->dyn_root) {
 467                 inode = afs_iget_pseudo_dir(sb, true);
 468         } else {
 469                 sprintf(sb->s_id, "%llu", as->volume->vid);
 470                 afs_activate_volume(as->volume);
 471                 inode = afs_root_iget(sb, ctx->key);
 472         }
 473
 474         if (IS_ERR(inode))
 475                 return PTR_ERR(inode);
 476
 477         if (ctx->autocell || as->dyn_root)
 478                 set_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(inode)->flags);
 479
 480         ret = -ENOMEM;
 481         sb->s_root = d_make_root(inode);
 482         if (!sb->s_root)
 483                 goto error;
 484
 485         if (as->dyn_root) {
 486                 sb->s_d_op = &afs_dynroot_dentry_operations;
 487                 ret = afs_dynroot_populate(sb);
 488                 if (ret < 0)
 489                         goto error;
 490         } else {
 491                 sb->s_d_op = &afs_fs_dentry_operations;
 492                 rcu_assign_pointer(as->volume->sb, sb);
 493         }
 494
 495         _leave(" = 0");
 496         return 0;
 497
 498 error:
 499         _leave(" = %d", ret);
 500         return ret;
 501 }
 502
 503 static struct afs_super_info *afs_alloc_sbi(struct fs_context *fc)
 504 {
 505         struct afs_fs_context *ctx = fc->fs_private;
 506         struct afs_super_info *as;
 507
 508         as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
 509         if (as) {
 510                 as->net_ns = get_net(fc->net_ns);
 511                 as->flock_mode = ctx->flock_mode;
 512                 if (ctx->dyn_root) {
 513                         as->dyn_root = true;
 514                 } else {
 515                         as->cell = afs_use_cell(ctx->cell, afs_cell_trace_use_sbi);
 516                         as->volume = afs_get_volume(ctx->volume,
 517                                                     afs_volume_trace_get_alloc_sbi);
 518                 }
 519         }
 520         return as;
 521 }
 522
 523 static void afs_destroy_sbi(struct afs_super_info *as)
 524 {
 525         if (as) {
 526                 struct afs_net *net = afs_net(as->net_ns);
 527                 afs_put_volume(net, as->volume, afs_volume_trace_put_destroy_sbi);
 528                 afs_unuse_cell(net, as->cell, afs_cell_trace_unuse_sbi);
 529                 put_net(as->net_ns);
 530                 kfree(as);
 531         }
 532 }
 533
 534 static void afs_kill_super(struct super_block *sb)
 535 {
 536         struct afs_super_info *as = AFS_FS_S(sb);
 537
 538         if (as->dyn_root)
 539                 afs_dynroot_depopulate(sb);
 540
 541         /* Clear the callback interests (which will do ilookup5) before
 542          * deactivating the superblock.
 543          */
 544         if (as->volume)
 545                 rcu_assign_pointer(as->volume->sb, NULL);
 546         kill_anon_super(sb);
 547         if (as->volume)
 548                 afs_deactivate_volume(as->volume);
 549         afs_destroy_sbi(as);
 550 }
 551
 552 /*
 553  * Get an AFS superblock and root directory.
 554  */
 555 static int afs_get_tree(struct fs_context *fc)
 556 {
 557         struct afs_fs_context *ctx = fc->fs_private;
 558         struct super_block *sb;
 559         struct afs_super_info *as;
 560         int ret;
 561
 562         ret = afs_validate_fc(fc);
 563         if (ret)
 564                 goto error;
 565
 566         _enter("");
 567
 568         /* allocate a superblock info record */
 569         ret = -ENOMEM;
 570         as = afs_alloc_sbi(fc);
 571         if (!as)
 572                 goto error;
 573         fc->s_fs_info = as;
 574
 575         /* allocate a deviceless superblock */
 576         sb = sget_fc(fc,
 577                      as->dyn_root ? afs_dynroot_test_super : afs_test_super,
 578                      afs_set_super);
 579         if (IS_ERR(sb)) {
 580                 ret = PTR_ERR(sb);
 581                 goto error;
 582         }
 583
 584         if (!sb->s_root) {
 585                 /* initial superblock/root creation */
 586                 _debug("create");
 587                 ret = afs_fill_super(sb, ctx);
 588                 if (ret < 0)
 589                         goto error_sb;
 590                 sb->s_flags |= SB_ACTIVE;
 591         } else {
 592                 _debug("reuse");
 593                 ASSERTCMP(sb->s_flags, &, SB_ACTIVE);
 594         }
 595
 596         fc->root = dget(sb->s_root);
 597         trace_afs_get_tree(as->cell, as->volume);
 598         _leave(" = 0 [%p]", sb);
 599         return 0;
 600
 601 error_sb:
 602         deactivate_locked_super(sb);
 603 error:
 604         _leave(" = %d", ret);
 605         return ret;
 606 }
 607
 608 static void afs_free_fc(struct fs_context *fc)
 609 {
 610         struct afs_fs_context *ctx = fc->fs_private;
 611
 612         afs_destroy_sbi(fc->s_fs_info);
 613         afs_put_volume(ctx->net, ctx->volume, afs_volume_trace_put_free_fc);
 614         afs_unuse_cell(ctx->net, ctx->cell, afs_cell_trace_unuse_fc);
 615         key_put(ctx->key);
 616         kfree(ctx);
 617 }
 618
 619 static const struct fs_context_operations afs_context_ops = {
 620         .free           = afs_free_fc,
 621         .parse_param    = afs_parse_param,
 622         .get_tree       = afs_get_tree,
 623 };
 624
 625 /*
 626  * Set up the filesystem mount context.
 627  */
 628 static int afs_init_fs_context(struct fs_context *fc)
 629 {
 630         struct afs_fs_context *ctx;
 631         struct afs_cell *cell;
 632
 633         ctx = kzalloc(sizeof(struct afs_fs_context), GFP_KERNEL);
 634         if (!ctx)
 635                 return -ENOMEM;
 636
 637         ctx->type = AFSVL_ROVOL;
 638         ctx->net = afs_net(fc->net_ns);
 639
 640         /* Default to the workstation cell. */
 641         cell = afs_find_cell(ctx->net, NULL, 0, afs_cell_trace_use_fc);
 642         if (IS_ERR(cell))
 643                 cell = NULL;
 644         ctx->cell = cell;
 645
 646         fc->fs_private = ctx;
 647         fc->ops = &afs_context_ops;
 648         return 0;
 649 }
 650
 651 /*
 652  * Initialise an inode cache slab element prior to any use.  Note that
 653  * afs_alloc_inode() *must* reset anything that could incorrectly leak from one
 654  * inode to another.
 655  */
 656 static void afs_i_init_once(void *_vnode)
 657 {
 658         struct afs_vnode *vnode = _vnode;
 659
 660         memset(vnode, 0, sizeof(*vnode));
 661         inode_init_once(&vnode->vfs_inode);
 662         mutex_init(&vnode->io_lock);
 663         init_rwsem(&vnode->validate_lock);
 664         spin_lock_init(&vnode->wb_lock);
 665         spin_lock_init(&vnode->lock);
 666         INIT_LIST_HEAD(&vnode->wb_keys);
 667         INIT_LIST_HEAD(&vnode->pending_locks);
 668         INIT_LIST_HEAD(&vnode->granted_locks);
 669         INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
 670         seqlock_init(&vnode->cb_lock);
 671 }
 672
 673 /*
 674  * allocate an AFS inode struct from our slab cache
 675  */
 676 static struct inode *afs_alloc_inode(struct super_block *sb)
 677 {
 678         struct afs_vnode *vnode;
 679
 680         vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
 681         if (!vnode)
 682                 return NULL;
 683
 684         atomic_inc(&afs_count_active_inodes);
 685
 686         /* Reset anything that shouldn't leak from one inode to the next. */
 687         memset(&vnode->fid, 0, sizeof(vnode->fid));
 688         memset(&vnode->status, 0, sizeof(vnode->status));
 689
 690         vnode->volume           = NULL;
 691         vnode->lock_key         = NULL;
 692         vnode->permit_cache     = NULL;
 693 #ifdef CONFIG_AFS_FSCACHE
 694         vnode->cache            = NULL;
 695 #endif
 696
 697         vnode->flags            = 1 << AFS_VNODE_UNSET;
 698         vnode->lock_state       = AFS_VNODE_LOCK_NONE;
 699
 700         init_rwsem(&vnode->rmdir_lock);
 701         INIT_WORK(&vnode->cb_work, afs_invalidate_mmap_work);
 702
 703         _leave(" = %p", &vnode->vfs_inode);
 704         return &vnode->vfs_inode;
 705 }
 706
 707 static void afs_free_inode(struct inode *inode)
 708 {
 709         kmem_cache_free(afs_inode_cachep, AFS_FS_I(inode));
 710 }
 711
 712 /*
 713  * destroy an AFS inode struct
 714  */
 715 static void afs_destroy_inode(struct inode *inode)
 716 {
 717         struct afs_vnode *vnode = AFS_FS_I(inode);
 718
 719         _enter("%p{%llx:%llu}", inode, vnode->fid.vid, vnode->fid.vnode);
 720
 721         _debug("DESTROY INODE %p", inode);
 722
 723         atomic_dec(&afs_count_active_inodes);
 724 }
 725
 726 static void afs_get_volume_status_success(struct afs_operation *op)
 727 {
 728         struct afs_volume_status *vs = &op->volstatus.vs;
 729         struct kstatfs *buf = op->volstatus.buf;
 730
 731         if (vs->max_quota == 0)
 732                 buf->f_blocks = vs->part_max_blocks;
 733         else
 734                 buf->f_blocks = vs->max_quota;
 735
 736         if (buf->f_blocks > vs->blocks_in_use)
 737                 buf->f_bavail = buf->f_bfree =
 738                         buf->f_blocks - vs->blocks_in_use;
 739 }
 740
 741 static const struct afs_operation_ops afs_get_volume_status_operation = {
 742         .issue_afs_rpc  = afs_fs_get_volume_status,
 743         .issue_yfs_rpc  = yfs_fs_get_volume_status,
 744         .success        = afs_get_volume_status_success,
 745 };
 746
 747 /*
 748  * return information about an AFS volume
 749  */
 750 static int afs_statfs(struct dentry *dentry, struct kstatfs *buf)
 751 {
 752         struct afs_super_info *as = AFS_FS_S(dentry->d_sb);
 753         struct afs_operation *op;
 754         struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
 755
 756         buf->f_type     = dentry->d_sb->s_magic;
 757         buf->f_bsize    = AFS_BLOCK_SIZE;
 758         buf->f_namelen  = AFSNAMEMAX - 1;
 759
 760         if (as->dyn_root) {
 761                 buf->f_blocks   = 1;
 762                 buf->f_bavail   = 0;
 763                 buf->f_bfree    = 0;
 764                 return 0;
 765         }
 766
 767         op = afs_alloc_operation(NULL, as->volume);
 768         if (IS_ERR(op))
 769                 return PTR_ERR(op);
 770
 771         afs_op_set_vnode(op, 0, vnode);
 772         op->nr_files            = 1;
 773         op->volstatus.buf       = buf;
 774         op->ops                 = &afs_get_volume_status_operation;
 775         return afs_do_sync_operation(op);
 776 }