fs/afs/inode.c

   1 /*
   2  * Copyright (c) 2002 Red Hat, Inc. All rights reserved.
   3  *
   4  * This software may be freely redistributed under the terms of the
   5  * GNU General Public License.
   6  *
   7  * You should have received a copy of the GNU General Public License
   8  * along with this program; if not, write to the Free Software
   9  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  10  *
  11  * Authors: David Woodhouse <dwmw2@infradead.org>
  12  *          David Howells <dhowells@redhat.com>
  13  *
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/init.h>
  19 #include <linux/fs.h>
  20 #include <linux/pagemap.h>
  21 #include <linux/sched.h>
  22 #include <linux/mount.h>
  23 #include <linux/namei.h>
  24 #include <linux/iversion.h>
  25 #include "internal.h"
  26
  27 static const struct inode_operations afs_symlink_inode_operations = {
  28         .get_link       = page_get_link,
  29         .listxattr      = afs_listxattr,
  30 };
  31
  32 static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode)
  33 {
  34         static unsigned long once_only;
  35
  36         pr_warn("kAFS: AFS vnode with undefined type %u\n",
  37                 vnode->status.type);
  38         pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n",
  39                 vnode->status.abort_code,
  40                 vnode->status.mode,
  41                 vnode->status.size,
  42                 vnode->status.data_version);
  43         pr_warn("kAFS: vnode %llx:%llx:%x\n",
  44                 vnode->fid.vid,
  45                 vnode->fid.vnode,
  46                 vnode->fid.unique);
  47         if (parent_vnode)
  48                 pr_warn("kAFS: dir %llx:%llx:%x\n",
  49                         parent_vnode->fid.vid,
  50                         parent_vnode->fid.vnode,
  51                         parent_vnode->fid.unique);
  52
  53         if (!test_and_set_bit(0, &once_only))
  54                 dump_stack();
  55 }
  56
  57 /*
  58  * Initialise an inode from the vnode status.
  59  */
  60 static int afs_inode_init_from_status(struct afs_vnode *vnode, struct key *key,
  61                                       struct afs_cb_interest *cbi,
  62                                       struct afs_vnode *parent_vnode,
  63                                       struct afs_status_cb *scb)
  64 {
  65         struct afs_cb_interest *old_cbi = NULL;
  66         struct afs_file_status *status = &scb->status;
  67         struct inode *inode = AFS_VNODE_TO_I(vnode);
  68         struct timespec64 t;
  69
  70         _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
  71                status->type,
  72                status->nlink,
  73                (unsigned long long) status->size,
  74                status->data_version,
  75                status->mode);
  76
  77         write_seqlock(&vnode->cb_lock);
  78
  79         vnode->status = *status;
  80
  81         t = status->mtime_client;
  82         inode->i_ctime = t;
  83         inode->i_mtime = t;
  84         inode->i_atime = t;
  85         inode->i_uid = make_kuid(&init_user_ns, status->owner);
  86         inode->i_gid = make_kgid(&init_user_ns, status->group);
  87         set_nlink(&vnode->vfs_inode, status->nlink);
  88
  89         switch (status->type) {
  90         case AFS_FTYPE_FILE:
  91                 inode->i_mode   = S_IFREG | status->mode;
  92                 inode->i_op     = &afs_file_inode_operations;
  93                 inode->i_fop    = &afs_file_operations;
  94                 inode->i_mapping->a_ops = &afs_fs_aops;
  95                 break;
  96         case AFS_FTYPE_DIR:
  97                 inode->i_mode   = S_IFDIR | status->mode;
  98                 inode->i_op     = &afs_dir_inode_operations;
  99                 inode->i_fop    = &afs_dir_file_operations;
 100                 inode->i_mapping->a_ops = &afs_dir_aops;
 101                 break;
 102         case AFS_FTYPE_SYMLINK:
 103                 /* Symlinks with a mode of 0644 are actually mountpoints. */
 104                 if ((status->mode & 0777) == 0644) {
 105                         inode->i_flags |= S_AUTOMOUNT;
 106
 107                         set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
 108
 109                         inode->i_mode   = S_IFDIR | 0555;
 110                         inode->i_op     = &afs_mntpt_inode_operations;
 111                         inode->i_fop    = &afs_mntpt_file_operations;
 112                         inode->i_mapping->a_ops = &afs_fs_aops;
 113                 } else {
 114                         inode->i_mode   = S_IFLNK | status->mode;
 115                         inode->i_op     = &afs_symlink_inode_operations;
 116                         inode->i_mapping->a_ops = &afs_fs_aops;
 117                 }
 118                 inode_nohighmem(inode);
 119                 break;
 120         default:
 121                 dump_vnode(vnode, parent_vnode);
 122                 write_sequnlock(&vnode->cb_lock);
 123                 return afs_protocol_error(NULL, -EBADMSG, afs_eproto_file_type);
 124         }
 125
 126         /*
 127          * Estimate 512 bytes  blocks used, rounded up to nearest 1K
 128          * for consistency with other AFS clients.
 129          */
 130         inode->i_blocks         = ((i_size_read(inode) + 1023) >> 10) << 1;
 131         i_size_write(&vnode->vfs_inode, status->size);
 132
 133         vnode->invalid_before   = status->data_version;
 134         inode_set_iversion_raw(&vnode->vfs_inode, status->data_version);
 135
 136         if (!scb->have_cb) {
 137                 /* it's a symlink we just created (the fileserver
 138                  * didn't give us a callback) */
 139                 vnode->cb_expires_at = ktime_get_real_seconds();
 140         } else {
 141                 vnode->cb_expires_at = scb->callback.expires_at;
 142                 old_cbi = vnode->cb_interest;
 143                 if (cbi != old_cbi)
 144                         vnode->cb_interest = afs_get_cb_interest(cbi);
 145                 else
 146                         old_cbi = NULL;
 147                 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
 148         }
 149
 150         write_sequnlock(&vnode->cb_lock);
 151         afs_put_cb_interest(afs_v2net(vnode), old_cbi);
 152         return 0;
 153 }
 154
 155 /*
 156  * Update the core inode struct from a returned status record.
 157  */
 158 static void afs_apply_status(struct afs_fs_cursor *fc,
 159                              struct afs_vnode *vnode,
 160                              struct afs_status_cb *scb,
 161                              const afs_dataversion_t *expected_version)
 162 {
 163         struct afs_file_status *status = &scb->status;
 164         struct timespec64 t;
 165         umode_t mode;
 166         bool data_changed = false;
 167
 168         BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));
 169
 170         if (status->type != vnode->status.type) {
 171                 pr_warning("Vnode %llx:%llx:%x changed type %u to %u\n",
 172                            vnode->fid.vid,
 173                            vnode->fid.vnode,
 174                            vnode->fid.unique,
 175                            status->type, vnode->status.type);
 176                 afs_protocol_error(NULL, -EBADMSG, afs_eproto_bad_status);
 177                 return;
 178         }
 179
 180         if (status->nlink != vnode->status.nlink)
 181                 set_nlink(&vnode->vfs_inode, status->nlink);
 182
 183         if (status->owner != vnode->status.owner)
 184                 vnode->vfs_inode.i_uid = make_kuid(&init_user_ns, status->owner);
 185
 186         if (status->group != vnode->status.group)
 187                 vnode->vfs_inode.i_gid = make_kgid(&init_user_ns, status->group);
 188
 189         if (status->mode != vnode->status.mode) {
 190                 mode = vnode->vfs_inode.i_mode;
 191                 mode &= ~S_IALLUGO;
 192                 mode |= status->mode;
 193                 WRITE_ONCE(vnode->vfs_inode.i_mode, mode);
 194         }
 195
 196         t = status->mtime_client;
 197         vnode->vfs_inode.i_ctime = t;
 198         vnode->vfs_inode.i_mtime = t;
 199         vnode->vfs_inode.i_atime = t;
 200
 201         if (vnode->status.data_version != status->data_version)
 202                 data_changed = true;
 203
 204         vnode->status = *status;
 205
 206         if (expected_version &&
 207             *expected_version != status->data_version) {
 208                 kdebug("vnode modified %llx on {%llx:%llu} [exp %llx] %s",
 209                        (unsigned long long) status->data_version,
 210                        vnode->fid.vid, vnode->fid.vnode,
 211                        (unsigned long long) *expected_version,
 212                        fc->type ? fc->type->name : "???");
 213                 vnode->invalid_before = status->data_version;
 214                 if (vnode->status.type == AFS_FTYPE_DIR) {
 215                         if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
 216                                 afs_stat_v(vnode, n_inval);
 217                 } else {
 218                         set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
 219                 }
 220         } else if (vnode->status.type == AFS_FTYPE_DIR) {
 221                 /* Expected directory change is handled elsewhere so
 222                  * that we can locally edit the directory and save on a
 223                  * download.
 224                  */
 225                 if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
 226                         data_changed = false;
 227         }
 228
 229         if (data_changed) {
 230                 inode_set_iversion_raw(&vnode->vfs_inode, status->data_version);
 231                 i_size_write(&vnode->vfs_inode, status->size);
 232         }
 233 }
 234
 235 /*
 236  * Apply a callback to a vnode.
 237  */
 238 static void afs_apply_callback(struct afs_fs_cursor *fc,
 239                                struct afs_vnode *vnode,
 240                                struct afs_status_cb *scb,
 241                                unsigned int cb_break)
 242 {
 243         struct afs_cb_interest *old;
 244         struct afs_callback *cb = &scb->callback;
 245
 246         if (!afs_cb_is_broken(cb_break, vnode, fc->cbi)) {
 247                 vnode->cb_expires_at    = cb->expires_at;
 248                 old = vnode->cb_interest;
 249                 if (old != fc->cbi) {
 250                         vnode->cb_interest = afs_get_cb_interest(fc->cbi);
 251                         afs_put_cb_interest(afs_v2net(vnode), old);
 252                 }
 253                 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
 254         }
 255 }
 256
 257 /*
 258  * Apply the received status and callback to an inode all in the same critical
 259  * section to avoid races with afs_validate().
 260  */
 261 void afs_vnode_commit_status(struct afs_fs_cursor *fc,
 262                              struct afs_vnode *vnode,
 263                              unsigned int cb_break,
 264                              const afs_dataversion_t *expected_version,
 265                              struct afs_status_cb *scb)
 266 {
 267         if (fc->ac.error != 0)
 268                 return;
 269
 270         write_seqlock(&vnode->cb_lock);
 271
 272         afs_apply_status(fc, vnode, scb, expected_version);
 273         if (scb->have_cb)
 274                 afs_apply_callback(fc, vnode, scb, cb_break);
 275
 276         write_sequnlock(&vnode->cb_lock);
 277
 278         if (fc->ac.error == 0)
 279                 afs_cache_permit(vnode, fc->key, cb_break, scb);
 280 }
 281
 282 /*
 283  * Fetch file status from the volume.
 284  */
 285 int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
 286                      afs_access_t *_caller_access)
 287 {
 288         struct afs_status_cb *scb;
 289         struct afs_fs_cursor fc;
 290         int ret;
 291
 292         _enter("%s,{%llx:%llu.%u,S=%lx}",
 293                vnode->volume->name,
 294                vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
 295                vnode->flags);
 296
 297         scb = kzalloc(sizeof(struct afs_status_cb), GFP_KERNEL);
 298         if (!scb)
 299                 return -ENOMEM;
 300
 301         ret = -ERESTARTSYS;
 302         if (afs_begin_vnode_operation(&fc, vnode, key, true)) {
 303                 afs_dataversion_t data_version = vnode->status.data_version;
 304
 305                 while (afs_select_fileserver(&fc)) {
 306                         fc.cb_break = afs_calc_vnode_cb_break(vnode);
 307                         afs_fs_fetch_file_status(&fc, scb, NULL);
 308                 }
 309
 310                 if (fc.error) {
 311                         /* Do nothing. */
 312                 } else if (is_new) {
 313                         ret = afs_inode_init_from_status(vnode, key, fc.cbi,
 314                                                          NULL, scb);
 315                         fc.error = ret;
 316                         if (ret == 0)
 317                                 afs_cache_permit(vnode, key, fc.cb_break, scb);
 318                 } else {
 319                         afs_vnode_commit_status(&fc, vnode, fc.cb_break,
 320                                                 &data_version, scb);
 321                 }
 322                 afs_check_for_remote_deletion(&fc, vnode);
 323                 ret = afs_end_vnode_operation(&fc);
 324         }
 325
 326         if (ret == 0 && _caller_access)
 327                 *_caller_access = scb->status.caller_access;
 328         kfree(scb);
 329         _leave(" = %d", ret);
 330         return ret;
 331 }
 332
 333 /*
 334  * iget5() comparator
 335  */
 336 int afs_iget5_test(struct inode *inode, void *opaque)
 337 {
 338         struct afs_iget_data *data = opaque;
 339         struct afs_vnode *vnode = AFS_FS_I(inode);
 340
 341         return memcmp(&vnode->fid, &data->fid, sizeof(data->fid)) == 0;
 342 }
 343
 344 /*
 345  * iget5() comparator for inode created by autocell operations
 346  *
 347  * These pseudo inodes don't match anything.
 348  */
 349 static int afs_iget5_pseudo_dir_test(struct inode *inode, void *opaque)
 350 {
 351         return 0;
 352 }
 353
 354 /*
 355  * iget5() inode initialiser
 356  */
 357 static int afs_iget5_set(struct inode *inode, void *opaque)
 358 {
 359         struct afs_iget_data *data = opaque;
 360         struct afs_vnode *vnode = AFS_FS_I(inode);
 361
 362         vnode->fid = data->fid;
 363         vnode->volume = data->volume;
 364
 365         /* YFS supports 96-bit vnode IDs, but Linux only supports
 366          * 64-bit inode numbers.
 367          */
 368         inode->i_ino = data->fid.vnode;
 369         inode->i_generation = data->fid.unique;
 370         return 0;
 371 }
 372
 373 /*
 374  * Create an inode for a dynamic root directory or an autocell dynamic
 375  * automount dir.
 376  */
 377 struct inode *afs_iget_pseudo_dir(struct super_block *sb, bool root)
 378 {
 379         struct afs_iget_data data;
 380         struct afs_super_info *as;
 381         struct afs_vnode *vnode;
 382         struct inode *inode;
 383         static atomic_t afs_autocell_ino;
 384
 385         _enter("");
 386
 387         as = sb->s_fs_info;
 388         if (as->volume) {
 389                 data.volume = as->volume;
 390                 data.fid.vid = as->volume->vid;
 391         }
 392         if (root) {
 393                 data.fid.vnode = 1;
 394                 data.fid.unique = 1;
 395         } else {
 396                 data.fid.vnode = atomic_inc_return(&afs_autocell_ino);
 397                 data.fid.unique = 0;
 398         }
 399
 400         inode = iget5_locked(sb, data.fid.vnode,
 401                              afs_iget5_pseudo_dir_test, afs_iget5_set,
 402                              &data);
 403         if (!inode) {
 404                 _leave(" = -ENOMEM");
 405                 return ERR_PTR(-ENOMEM);
 406         }
 407
 408         _debug("GOT INODE %p { ino=%lu, vl=%llx, vn=%llx, u=%x }",
 409                inode, inode->i_ino, data.fid.vid, data.fid.vnode,
 410                data.fid.unique);
 411
 412         vnode = AFS_FS_I(inode);
 413
 414         /* there shouldn't be an existing inode */
 415         BUG_ON(!(inode->i_state & I_NEW));
 416
 417         inode->i_size           = 0;
 418         inode->i_mode           = S_IFDIR | S_IRUGO | S_IXUGO;
 419         if (root) {
 420                 inode->i_op     = &afs_dynroot_inode_operations;
 421                 inode->i_fop    = &afs_dynroot_file_operations;
 422         } else {
 423                 inode->i_op     = &afs_autocell_inode_operations;
 424         }
 425         set_nlink(inode, 2);
 426         inode->i_uid            = GLOBAL_ROOT_UID;
 427         inode->i_gid            = GLOBAL_ROOT_GID;
 428         inode->i_ctime = inode->i_atime = inode->i_mtime = current_time(inode);
 429         inode->i_blocks         = 0;
 430         inode_set_iversion_raw(inode, 0);
 431         inode->i_generation     = 0;
 432
 433         set_bit(AFS_VNODE_PSEUDODIR, &vnode->flags);
 434         if (!root) {
 435                 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
 436                 inode->i_flags |= S_AUTOMOUNT;
 437         }
 438
 439         inode->i_flags |= S_NOATIME;
 440         unlock_new_inode(inode);
 441         _leave(" = %p", inode);
 442         return inode;
 443 }
 444
 445 /*
 446  * Get a cache cookie for an inode.
 447  */
 448 static void afs_get_inode_cache(struct afs_vnode *vnode)
 449 {
 450 #ifdef CONFIG_AFS_FSCACHE
 451         struct {
 452                 u32 vnode_id;
 453                 u32 unique;
 454                 u32 vnode_id_ext[2];    /* Allow for a 96-bit key */
 455         } __packed key;
 456         struct afs_vnode_cache_aux aux;
 457
 458         if (vnode->status.type == AFS_FTYPE_DIR) {
 459                 vnode->cache = NULL;
 460                 return;
 461         }
 462
 463         key.vnode_id            = vnode->fid.vnode;
 464         key.unique              = vnode->fid.unique;
 465         key.vnode_id_ext[0]     = vnode->fid.vnode >> 32;
 466         key.vnode_id_ext[1]     = vnode->fid.vnode_hi;
 467         aux.data_version        = vnode->status.data_version;
 468
 469         vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
 470                                               &afs_vnode_cache_index_def,
 471                                               &key, sizeof(key),
 472                                               &aux, sizeof(aux),
 473                                               vnode, vnode->status.size, true);
 474 #endif
 475 }
 476
 477 /*
 478  * inode retrieval
 479  */
 480 struct inode *afs_iget(struct super_block *sb, struct key *key,
 481                        struct afs_fid *fid, struct afs_status_cb *scb,
 482                        struct afs_cb_interest *cbi,
 483                        struct afs_vnode *parent_vnode)
 484 {
 485         struct afs_iget_data data = { .fid = *fid };
 486         struct afs_super_info *as;
 487         struct afs_vnode *vnode;
 488         struct inode *inode;
 489         int ret;
 490
 491         _enter(",{%llx:%llu.%u},,", fid->vid, fid->vnode, fid->unique);
 492
 493         as = sb->s_fs_info;
 494         data.volume = as->volume;
 495
 496         inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
 497                              &data);
 498         if (!inode) {
 499                 _leave(" = -ENOMEM");
 500                 return ERR_PTR(-ENOMEM);
 501         }
 502
 503         _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
 504                inode, fid->vid, fid->vnode, fid->unique);
 505
 506         vnode = AFS_FS_I(inode);
 507
 508         /* deal with an existing inode */
 509         if (!(inode->i_state & I_NEW)) {
 510                 _leave(" = %p", inode);
 511                 return inode;
 512         }
 513
 514         if (!scb) {
 515                 /* it's a remotely extant inode */
 516                 ret = afs_fetch_status(vnode, key, true, NULL);
 517                 if (ret < 0)
 518                         goto bad_inode;
 519         } else {
 520                 ret = afs_inode_init_from_status(vnode, key, cbi, parent_vnode,
 521                                                  scb);
 522                 if (ret < 0)
 523                         goto bad_inode;
 524         }
 525
 526         afs_get_inode_cache(vnode);
 527
 528         /* success */
 529         clear_bit(AFS_VNODE_UNSET, &vnode->flags);
 530         inode->i_flags |= S_NOATIME;
 531         unlock_new_inode(inode);
 532         _leave(" = %p", inode);
 533         return inode;
 534
 535         /* failure */
 536 bad_inode:
 537         iget_failed(inode);
 538         _leave(" = %d [bad]", ret);
 539         return ERR_PTR(ret);
 540 }
 541
 542 /*
 543  * mark the data attached to an inode as obsolete due to a write on the server
 544  * - might also want to ditch all the outstanding writes and dirty pages
 545  */
 546 void afs_zap_data(struct afs_vnode *vnode)
 547 {
 548         _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
 549
 550 #ifdef CONFIG_AFS_FSCACHE
 551         fscache_invalidate(vnode->cache);
 552 #endif
 553
 554         /* nuke all the non-dirty pages that aren't locked, mapped or being
 555          * written back in a regular file and completely discard the pages in a
 556          * directory or symlink */
 557         if (S_ISREG(vnode->vfs_inode.i_mode))
 558                 invalidate_remote_inode(&vnode->vfs_inode);
 559         else
 560                 invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
 561 }
 562
 563 /*
 564  * validate a vnode/inode
 565  * - there are several things we need to check
 566  *   - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
 567  *     symlink)
 568  *   - parent dir metadata changed (security changes)
 569  *   - dentry data changed (write, truncate)
 570  *   - dentry metadata changed (security changes)
 571  */
 572 int afs_validate(struct afs_vnode *vnode, struct key *key)
 573 {
 574         time64_t now = ktime_get_real_seconds();
 575         bool valid;
 576         int ret;
 577
 578         _enter("{v={%llx:%llu} fl=%lx},%x",
 579                vnode->fid.vid, vnode->fid.vnode, vnode->flags,
 580                key_serial(key));
 581
 582         /* Quickly check the callback state.  Ideally, we'd use read_seqbegin
 583          * here, but we have no way to pass the net namespace to the RCU
 584          * cleanup for the server record.
 585          */
 586         read_seqlock_excl(&vnode->cb_lock);
 587
 588         if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
 589                 if (vnode->cb_s_break != vnode->cb_interest->server->cb_s_break ||
 590                     vnode->cb_v_break != vnode->volume->cb_v_break) {
 591                         vnode->cb_s_break = vnode->cb_interest->server->cb_s_break;
 592                         vnode->cb_v_break = vnode->volume->cb_v_break;
 593                         valid = false;
 594                 } else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
 595                         valid = false;
 596                 } else if (vnode->cb_expires_at - 10 <= now) {
 597                         valid = false;
 598                 } else {
 599                         valid = true;
 600                 }
 601         } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
 602                 valid = true;
 603         } else {
 604                 vnode->cb_v_break = vnode->volume->cb_v_break;
 605                 valid = false;
 606         }
 607
 608         read_sequnlock_excl(&vnode->cb_lock);
 609
 610         if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
 611                 clear_nlink(&vnode->vfs_inode);
 612
 613         if (valid)
 614                 goto valid;
 615
 616         down_write(&vnode->validate_lock);
 617
 618         /* if the promise has expired, we need to check the server again to get
 619          * a new promise - note that if the (parent) directory's metadata was
 620          * changed then the security may be different and we may no longer have
 621          * access */
 622         if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
 623                 _debug("not promised");
 624                 ret = afs_fetch_status(vnode, key, false, NULL);
 625                 if (ret < 0) {
 626                         if (ret == -ENOENT) {
 627                                 set_bit(AFS_VNODE_DELETED, &vnode->flags);
 628                                 ret = -ESTALE;
 629                         }
 630                         goto error_unlock;
 631                 }
 632                 _debug("new promise [fl=%lx]", vnode->flags);
 633         }
 634
 635         if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
 636                 _debug("file already deleted");
 637                 ret = -ESTALE;
 638                 goto error_unlock;
 639         }
 640
 641         /* if the vnode's data version number changed then its contents are
 642          * different */
 643         if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
 644                 afs_zap_data(vnode);
 645         up_write(&vnode->validate_lock);
 646 valid:
 647         _leave(" = 0");
 648         return 0;
 649
 650 error_unlock:
 651         up_write(&vnode->validate_lock);
 652         _leave(" = %d", ret);
 653         return ret;
 654 }
 655
 656 /*
 657  * read the attributes of an inode
 658  */
 659 int afs_getattr(const struct path *path, struct kstat *stat,
 660                 u32 request_mask, unsigned int query_flags)
 661 {
 662         struct inode *inode = d_inode(path->dentry);
 663         struct afs_vnode *vnode = AFS_FS_I(inode);
 664         int seq = 0;
 665
 666         _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
 667
 668         do {
 669                 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
 670                 generic_fillattr(inode, stat);
 671         } while (need_seqretry(&vnode->cb_lock, seq));
 672
 673         done_seqretry(&vnode->cb_lock, seq);
 674         return 0;
 675 }
 676
 677 /*
 678  * discard an AFS inode
 679  */
 680 int afs_drop_inode(struct inode *inode)
 681 {
 682         _enter("");
 683
 684         if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
 685                 return generic_delete_inode(inode);
 686         else
 687                 return generic_drop_inode(inode);
 688 }
 689
 690 /*
 691  * clear an AFS inode
 692  */
 693 void afs_evict_inode(struct inode *inode)
 694 {
 695         struct afs_vnode *vnode;
 696
 697         vnode = AFS_FS_I(inode);
 698
 699         _enter("{%llx:%llu.%d}",
 700                vnode->fid.vid,
 701                vnode->fid.vnode,
 702                vnode->fid.unique);
 703
 704         _debug("CLEAR INODE %p", inode);
 705
 706         ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
 707
 708         truncate_inode_pages_final(&inode->i_data);
 709         clear_inode(inode);
 710
 711         if (vnode->cb_interest) {
 712                 afs_put_cb_interest(afs_i2net(inode), vnode->cb_interest);
 713                 vnode->cb_interest = NULL;
 714         }
 715
 716         while (!list_empty(&vnode->wb_keys)) {
 717                 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
 718                                                     struct afs_wb_key, vnode_link);
 719                 list_del(&wbk->vnode_link);
 720                 afs_put_wb_key(wbk);
 721         }
 722
 723 #ifdef CONFIG_AFS_FSCACHE
 724         {
 725                 struct afs_vnode_cache_aux aux;
 726
 727                 aux.data_version = vnode->status.data_version;
 728                 fscache_relinquish_cookie(vnode->cache, &aux,
 729                                           test_bit(AFS_VNODE_DELETED, &vnode->flags));
 730                 vnode->cache = NULL;
 731         }
 732 #endif
 733
 734         afs_prune_wb_keys(vnode);
 735         afs_put_permits(rcu_access_pointer(vnode->permit_cache));
 736         key_put(vnode->silly_key);
 737         vnode->silly_key = NULL;
 738         key_put(vnode->lock_key);
 739         vnode->lock_key = NULL;
 740         _leave("");
 741 }
 742
 743 /*
 744  * set the attributes of an inode
 745  */
 746 int afs_setattr(struct dentry *dentry, struct iattr *attr)
 747 {
 748         struct afs_fs_cursor fc;
 749         struct afs_status_cb *scb;
 750         struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
 751         struct key *key;
 752         int ret = -ENOMEM;
 753
 754         _enter("{%llx:%llu},{n=%pd},%x",
 755                vnode->fid.vid, vnode->fid.vnode, dentry,
 756                attr->ia_valid);
 757
 758         if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
 759                                 ATTR_MTIME))) {
 760                 _leave(" = 0 [unsupported]");
 761                 return 0;
 762         }
 763
 764         scb = kzalloc(sizeof(struct afs_status_cb), GFP_KERNEL);
 765         if (!scb)
 766                 goto error;
 767
 768         /* flush any dirty data outstanding on a regular file */
 769         if (S_ISREG(vnode->vfs_inode.i_mode))
 770                 filemap_write_and_wait(vnode->vfs_inode.i_mapping);
 771
 772         if (attr->ia_valid & ATTR_FILE) {
 773                 key = afs_file_key(attr->ia_file);
 774         } else {
 775                 key = afs_request_key(vnode->volume->cell);
 776                 if (IS_ERR(key)) {
 777                         ret = PTR_ERR(key);
 778                         goto error_scb;
 779                 }
 780         }
 781
 782         ret = -ERESTARTSYS;
 783         if (afs_begin_vnode_operation(&fc, vnode, key, false)) {
 784                 afs_dataversion_t data_version = vnode->status.data_version;
 785
 786                 if (attr->ia_valid & ATTR_SIZE)
 787                         data_version++;
 788
 789                 while (afs_select_fileserver(&fc)) {
 790                         fc.cb_break = afs_calc_vnode_cb_break(vnode);
 791                         afs_fs_setattr(&fc, attr, scb);
 792                 }
 793
 794                 afs_check_for_remote_deletion(&fc, vnode);
 795                 afs_vnode_commit_status(&fc, vnode, fc.cb_break,
 796                                         &data_version, scb);
 797                 ret = afs_end_vnode_operation(&fc);
 798         }
 799
 800         if (!(attr->ia_valid & ATTR_FILE))
 801                 key_put(key);
 802
 803 error_scb:
 804         kfree(scb);
 805 error:
 806         _leave(" = %d", ret);
 807         return ret;
 808 }