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 (!name) {
 234                 printk(KERN_ERR "kAFS: no volume name specified\n");
 235                 return -EINVAL;
 236         }
 237
 238         if ((name[0] != '%' && name[0] != '#') || !name[1]) {
 239                 /* To use dynroot, we don't want to have to provide a source */
 240                 if (strcmp(name, "none") == 0) {
 241                         ctx->no_cell = true;
 242                         return 0;
 243                 }
 244                 printk(KERN_ERR "kAFS: unparsable volume name\n");
 245                 return -EINVAL;
 246         }
 247
 248         /* determine the type of volume we're looking for */
 249         if (name[0] == '%') {
 250                 ctx->type = AFSVL_RWVOL;
 251                 ctx->force = true;
 252         }
 253         name++;
 254
 255         /* split the cell name out if there is one */
 256         ctx->volname = strchr(name, ':');
 257         if (ctx->volname) {
 258                 cellname = name;
 259                 cellnamesz = ctx->volname - name;
 260                 ctx->volname++;
 261         } else {
 262                 ctx->volname = name;
 263                 cellname = NULL;
 264                 cellnamesz = 0;
 265         }
 266
 267         /* the volume type is further affected by a possible suffix */
 268         suffix = strrchr(ctx->volname, '.');
 269         if (suffix) {
 270                 if (strcmp(suffix, ".readonly") == 0) {
 271                         ctx->type = AFSVL_ROVOL;
 272                         ctx->force = true;
 273                 } else if (strcmp(suffix, ".backup") == 0) {
 274                         ctx->type = AFSVL_BACKVOL;
 275                         ctx->force = true;
 276                 } else if (suffix[1] == 0) {
 277                 } else {
 278                         suffix = NULL;
 279                 }
 280         }
 281
 282         ctx->volnamesz = suffix ?
 283                 suffix - ctx->volname : strlen(ctx->volname);
 284
 285         _debug("cell %*.*s [%p]",
 286                cellnamesz, cellnamesz, cellname ?: "", ctx->cell);
 287
 288         /* lookup the cell record */
 289         if (cellname) {
 290                 cell = afs_lookup_cell(ctx->net, cellname, cellnamesz,
 291                                        NULL, false);
 292                 if (IS_ERR(cell)) {
 293                         pr_err("kAFS: unable to lookup cell '%*.*s'\n",
 294                                cellnamesz, cellnamesz, cellname ?: "");
 295                         return PTR_ERR(cell);
 296                 }
 297                 afs_unuse_cell(ctx->net, ctx->cell, afs_cell_trace_unuse_parse);
 298                 afs_see_cell(cell, afs_cell_trace_see_source);
 299                 ctx->cell = cell;
 300         }
 301
 302         _debug("CELL:%s [%p] VOLUME:%*.*s SUFFIX:%s TYPE:%d%s",
 303                ctx->cell->name, ctx->cell,
 304                ctx->volnamesz, ctx->volnamesz, ctx->volname,
 305                suffix ?: "-", ctx->type, ctx->force ? " FORCE" : "");
 306
 307         fc->source = param->string;
 308         param->string = NULL;
 309         return 0;
 310 }
 311
 312 /*
 313  * Parse a single mount parameter.
 314  */
 315 static int afs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 316 {
 317         struct fs_parse_result result;
 318         struct afs_fs_context *ctx = fc->fs_private;
 319         int opt;
 320
 321         opt = fs_parse(fc, afs_fs_parameters, param, &result);
 322         if (opt < 0)
 323                 return opt;
 324
 325         switch (opt) {
 326         case Opt_source:
 327                 return afs_parse_source(fc, param);
 328
 329         case Opt_autocell:
 330                 ctx->autocell = true;
 331                 break;
 332
 333         case Opt_dyn:
 334                 ctx->dyn_root = true;
 335                 break;
 336
 337         case Opt_flock:
 338                 ctx->flock_mode = result.uint_32;
 339                 break;
 340
 341         default:
 342                 return -EINVAL;
 343         }
 344
 345         _leave(" = 0");
 346         return 0;
 347 }
 348
 349 /*
 350  * Validate the options, get the cell key and look up the volume.
 351  */
 352 static int afs_validate_fc(struct fs_context *fc)
 353 {
 354         struct afs_fs_context *ctx = fc->fs_private;
 355         struct afs_volume *volume;
 356         struct afs_cell *cell;
 357         struct key *key;
 358         int ret;
 359
 360         if (!ctx->dyn_root) {
 361                 if (ctx->no_cell) {
 362                         pr_warn("kAFS: Can only specify source 'none' with -o dyn\n");
 363                         return -EINVAL;
 364                 }
 365
 366                 if (!ctx->cell) {
 367                         pr_warn("kAFS: No cell specified\n");
 368                         return -EDESTADDRREQ;
 369                 }
 370
 371         reget_key:
 372                 /* We try to do the mount securely. */
 373                 key = afs_request_key(ctx->cell);
 374                 if (IS_ERR(key))
 375                         return PTR_ERR(key);
 376
 377                 ctx->key = key;
 378
 379                 if (ctx->volume) {
 380                         afs_put_volume(ctx->net, ctx->volume,
 381                                        afs_volume_trace_put_validate_fc);
 382                         ctx->volume = NULL;
 383                 }
 384
 385                 if (test_bit(AFS_CELL_FL_CHECK_ALIAS, &ctx->cell->flags)) {
 386                         ret = afs_cell_detect_alias(ctx->cell, key);
 387                         if (ret < 0)
 388                                 return ret;
 389                         if (ret == 1) {
 390                                 _debug("switch to alias");
 391                                 key_put(ctx->key);
 392                                 ctx->key = NULL;
 393                                 cell = afs_use_cell(ctx->cell->alias_of,
 394                                                     afs_cell_trace_use_fc_alias);
 395                                 afs_unuse_cell(ctx->net, ctx->cell, afs_cell_trace_unuse_fc);
 396                                 ctx->cell = cell;
 397                                 goto reget_key;
 398                         }
 399                 }
 400
 401                 volume = afs_create_volume(ctx);
 402                 if (IS_ERR(volume))
 403                         return PTR_ERR(volume);
 404
 405                 ctx->volume = volume;
 406         }
 407
 408         return 0;
 409 }
 410
 411 /*
 412  * check a superblock to see if it's the one we're looking for
 413  */
 414 static int afs_test_super(struct super_block *sb, struct fs_context *fc)
 415 {
 416         struct afs_fs_context *ctx = fc->fs_private;
 417         struct afs_super_info *as = AFS_FS_S(sb);
 418
 419         return (as->net_ns == fc->net_ns &&
 420                 as->volume &&
 421                 as->volume->vid == ctx->volume->vid &&
 422                 as->cell == ctx->cell &&
 423                 !as->dyn_root);
 424 }
 425
 426 static int afs_dynroot_test_super(struct super_block *sb, struct fs_context *fc)
 427 {
 428         struct afs_super_info *as = AFS_FS_S(sb);
 429
 430         return (as->net_ns == fc->net_ns &&
 431                 as->dyn_root);
 432 }
 433
 434 static int afs_set_super(struct super_block *sb, struct fs_context *fc)
 435 {
 436         return set_anon_super(sb, NULL);
 437 }
 438
 439 /*
 440  * fill in the superblock
 441  */
 442 static int afs_fill_super(struct super_block *sb, struct afs_fs_context *ctx)
 443 {
 444         struct afs_super_info *as = AFS_FS_S(sb);
 445         struct inode *inode = NULL;
 446         int ret;
 447
 448         _enter("");
 449
 450         /* fill in the superblock */
 451         sb->s_blocksize         = PAGE_SIZE;
 452         sb->s_blocksize_bits    = PAGE_SHIFT;
 453         sb->s_maxbytes          = MAX_LFS_FILESIZE;
 454         sb->s_magic             = AFS_FS_MAGIC;
 455         sb->s_op                = &afs_super_ops;
 456         if (!as->dyn_root)
 457                 sb->s_xattr     = afs_xattr_handlers;
 458         ret = super_setup_bdi(sb);
 459         if (ret)
 460                 return ret;
 461
 462         /* allocate the root inode and dentry */
 463         if (as->dyn_root) {
 464                 inode = afs_iget_pseudo_dir(sb, true);
 465         } else {
 466                 sprintf(sb->s_id, "%llu", as->volume->vid);
 467                 afs_activate_volume(as->volume);
 468                 inode = afs_root_iget(sb, ctx->key);
 469         }
 470
 471         if (IS_ERR(inode))
 472                 return PTR_ERR(inode);
 473
 474         if (ctx->autocell || as->dyn_root)
 475                 set_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(inode)->flags);
 476
 477         ret = -ENOMEM;
 478         sb->s_root = d_make_root(inode);
 479         if (!sb->s_root)
 480                 goto error;
 481
 482         if (as->dyn_root) {
 483                 sb->s_d_op = &afs_dynroot_dentry_operations;
 484                 ret = afs_dynroot_populate(sb);
 485                 if (ret < 0)
 486                         goto error;
 487         } else {
 488                 sb->s_d_op = &afs_fs_dentry_operations;
 489                 rcu_assign_pointer(as->volume->sb, sb);
 490         }
 491
 492         _leave(" = 0");
 493         return 0;
 494
 495 error:
 496         _leave(" = %d", ret);
 497         return ret;
 498 }
 499
 500 static struct afs_super_info *afs_alloc_sbi(struct fs_context *fc)
 501 {
 502         struct afs_fs_context *ctx = fc->fs_private;
 503         struct afs_super_info *as;
 504
 505         as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
 506         if (as) {
 507                 as->net_ns = get_net(fc->net_ns);
 508                 as->flock_mode = ctx->flock_mode;
 509                 if (ctx->dyn_root) {
 510                         as->dyn_root = true;
 511                 } else {
 512                         as->cell = afs_use_cell(ctx->cell, afs_cell_trace_use_sbi);
 513                         as->volume = afs_get_volume(ctx->volume,
 514                                                     afs_volume_trace_get_alloc_sbi);
 515                 }
 516         }
 517         return as;
 518 }
 519
 520 static void afs_destroy_sbi(struct afs_super_info *as)
 521 {
 522         if (as) {
 523                 struct afs_net *net = afs_net(as->net_ns);
 524                 afs_put_volume(net, as->volume, afs_volume_trace_put_destroy_sbi);
 525                 afs_unuse_cell(net, as->cell, afs_cell_trace_unuse_sbi);
 526                 put_net(as->net_ns);
 527                 kfree(as);
 528         }
 529 }
 530
 531 static void afs_kill_super(struct super_block *sb)
 532 {
 533         struct afs_super_info *as = AFS_FS_S(sb);
 534
 535         if (as->dyn_root)
 536                 afs_dynroot_depopulate(sb);
 537
 538         /* Clear the callback interests (which will do ilookup5) before
 539          * deactivating the superblock.
 540          */
 541         if (as->volume)
 542                 rcu_assign_pointer(as->volume->sb, NULL);
 543         kill_anon_super(sb);
 544         if (as->volume)
 545                 afs_deactivate_volume(as->volume);
 546         afs_destroy_sbi(as);
 547 }
 548
 549 /*
 550  * Get an AFS superblock and root directory.
 551  */
 552 static int afs_get_tree(struct fs_context *fc)
 553 {
 554         struct afs_fs_context *ctx = fc->fs_private;
 555         struct super_block *sb;
 556         struct afs_super_info *as;
 557         int ret;
 558
 559         ret = afs_validate_fc(fc);
 560         if (ret)
 561                 goto error;
 562
 563         _enter("");
 564
 565         /* allocate a superblock info record */
 566         ret = -ENOMEM;
 567         as = afs_alloc_sbi(fc);
 568         if (!as)
 569                 goto error;
 570         fc->s_fs_info = as;
 571
 572         /* allocate a deviceless superblock */
 573         sb = sget_fc(fc,
 574                      as->dyn_root ? afs_dynroot_test_super : afs_test_super,
 575                      afs_set_super);
 576         if (IS_ERR(sb)) {
 577                 ret = PTR_ERR(sb);
 578                 goto error;
 579         }
 580
 581         if (!sb->s_root) {
 582                 /* initial superblock/root creation */
 583                 _debug("create");
 584                 ret = afs_fill_super(sb, ctx);
 585                 if (ret < 0)
 586                         goto error_sb;
 587                 sb->s_flags |= SB_ACTIVE;
 588         } else {
 589                 _debug("reuse");
 590                 ASSERTCMP(sb->s_flags, &, SB_ACTIVE);
 591         }
 592
 593         fc->root = dget(sb->s_root);
 594         trace_afs_get_tree(as->cell, as->volume);
 595         _leave(" = 0 [%p]", sb);
 596         return 0;
 597
 598 error_sb:
 599         deactivate_locked_super(sb);
 600 error:
 601         _leave(" = %d", ret);
 602         return ret;
 603 }
 604
 605 static void afs_free_fc(struct fs_context *fc)
 606 {
 607         struct afs_fs_context *ctx = fc->fs_private;
 608
 609         afs_destroy_sbi(fc->s_fs_info);
 610         afs_put_volume(ctx->net, ctx->volume, afs_volume_trace_put_free_fc);
 611         afs_unuse_cell(ctx->net, ctx->cell, afs_cell_trace_unuse_fc);
 612         key_put(ctx->key);
 613         kfree(ctx);
 614 }
 615
 616 static const struct fs_context_operations afs_context_ops = {
 617         .free           = afs_free_fc,
 618         .parse_param    = afs_parse_param,
 619         .get_tree       = afs_get_tree,
 620 };
 621
 622 /*
 623  * Set up the filesystem mount context.
 624  */
 625 static int afs_init_fs_context(struct fs_context *fc)
 626 {
 627         struct afs_fs_context *ctx;
 628         struct afs_cell *cell;
 629
 630         ctx = kzalloc(sizeof(struct afs_fs_context), GFP_KERNEL);
 631         if (!ctx)
 632                 return -ENOMEM;
 633
 634         ctx->type = AFSVL_ROVOL;
 635         ctx->net = afs_net(fc->net_ns);
 636
 637         /* Default to the workstation cell. */
 638         cell = afs_find_cell(ctx->net, NULL, 0, afs_cell_trace_use_fc);
 639         if (IS_ERR(cell))
 640                 cell = NULL;
 641         ctx->cell = cell;
 642
 643         fc->fs_private = ctx;
 644         fc->ops = &afs_context_ops;
 645         return 0;
 646 }
 647
 648 /*
 649  * Initialise an inode cache slab element prior to any use.  Note that
 650  * afs_alloc_inode() *must* reset anything that could incorrectly leak from one
 651  * inode to another.
 652  */
 653 static void afs_i_init_once(void *_vnode)
 654 {
 655         struct afs_vnode *vnode = _vnode;
 656
 657         memset(vnode, 0, sizeof(*vnode));
 658         inode_init_once(&vnode->vfs_inode);
 659         mutex_init(&vnode->io_lock);
 660         init_rwsem(&vnode->validate_lock);
 661         spin_lock_init(&vnode->wb_lock);
 662         spin_lock_init(&vnode->lock);
 663         INIT_LIST_HEAD(&vnode->wb_keys);
 664         INIT_LIST_HEAD(&vnode->pending_locks);
 665         INIT_LIST_HEAD(&vnode->granted_locks);
 666         INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
 667         seqlock_init(&vnode->cb_lock);
 668 }
 669
 670 /*
 671  * allocate an AFS inode struct from our slab cache
 672  */
 673 static struct inode *afs_alloc_inode(struct super_block *sb)
 674 {
 675         struct afs_vnode *vnode;
 676
 677         vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
 678         if (!vnode)
 679                 return NULL;
 680
 681         atomic_inc(&afs_count_active_inodes);
 682
 683         /* Reset anything that shouldn't leak from one inode to the next. */
 684         memset(&vnode->fid, 0, sizeof(vnode->fid));
 685         memset(&vnode->status, 0, sizeof(vnode->status));
 686
 687         vnode->volume           = NULL;
 688         vnode->lock_key         = NULL;
 689         vnode->permit_cache     = NULL;
 690 #ifdef CONFIG_AFS_FSCACHE
 691         vnode->cache            = NULL;
 692 #endif
 693
 694         vnode->flags            = 1 << AFS_VNODE_UNSET;
 695         vnode->lock_state       = AFS_VNODE_LOCK_NONE;
 696
 697         init_rwsem(&vnode->rmdir_lock);
 698
 699         _leave(" = %p", &vnode->vfs_inode);
 700         return &vnode->vfs_inode;
 701 }
 702
 703 static void afs_free_inode(struct inode *inode)
 704 {
 705         kmem_cache_free(afs_inode_cachep, AFS_FS_I(inode));
 706 }
 707
 708 /*
 709  * destroy an AFS inode struct
 710  */
 711 static void afs_destroy_inode(struct inode *inode)
 712 {
 713         struct afs_vnode *vnode = AFS_FS_I(inode);
 714
 715         _enter("%p{%llx:%llu}", inode, vnode->fid.vid, vnode->fid.vnode);
 716
 717         _debug("DESTROY INODE %p", inode);
 718
 719         atomic_dec(&afs_count_active_inodes);
 720 }
 721
 722 static void afs_get_volume_status_success(struct afs_operation *op)
 723 {
 724         struct afs_volume_status *vs = &op->volstatus.vs;
 725         struct kstatfs *buf = op->volstatus.buf;
 726
 727         if (vs->max_quota == 0)
 728                 buf->f_blocks = vs->part_max_blocks;
 729         else
 730                 buf->f_blocks = vs->max_quota;
 731
 732         if (buf->f_blocks > vs->blocks_in_use)
 733                 buf->f_bavail = buf->f_bfree =
 734                         buf->f_blocks - vs->blocks_in_use;
 735 }
 736
 737 static const struct afs_operation_ops afs_get_volume_status_operation = {
 738         .issue_afs_rpc  = afs_fs_get_volume_status,
 739         .issue_yfs_rpc  = yfs_fs_get_volume_status,
 740         .success        = afs_get_volume_status_success,
 741 };
 742
 743 /*
 744  * return information about an AFS volume
 745  */
 746 static int afs_statfs(struct dentry *dentry, struct kstatfs *buf)
 747 {
 748         struct afs_super_info *as = AFS_FS_S(dentry->d_sb);
 749         struct afs_operation *op;
 750         struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
 751
 752         buf->f_type     = dentry->d_sb->s_magic;
 753         buf->f_bsize    = AFS_BLOCK_SIZE;
 754         buf->f_namelen  = AFSNAMEMAX - 1;
 755
 756         if (as->dyn_root) {
 757                 buf->f_blocks   = 1;
 758                 buf->f_bavail   = 0;
 759                 buf->f_bfree    = 0;
 760                 return 0;
 761         }
 762
 763         op = afs_alloc_operation(NULL, as->volume);
 764         if (IS_ERR(op))
 765                 return PTR_ERR(op);
 766
 767         afs_op_set_vnode(op, 0, vnode);
 768         op->nr_files            = 1;
 769         op->volstatus.buf       = buf;
 770         op->ops                 = &afs_get_volume_status_operation;
 771         return afs_do_sync_operation(op);
 772 }