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 #include "afs_fs.h"
  27
  28 void afs_init_new_symlink(struct afs_vnode *vnode, struct afs_operation *op)
  29 {
  30         size_t size = strlen(op->create.symlink) + 1;
  31         size_t dsize = 0;
  32         char *p;
  33
  34         if (netfs_alloc_folioq_buffer(NULL, &vnode->directory, &dsize, size,
  35                                       mapping_gfp_mask(vnode->netfs.inode.i_mapping)) < 0)
  36                 return;
  37
  38         vnode->directory_size = dsize;
  39         p = kmap_local_folio(folioq_folio(vnode->directory, 0), 0);
  40         memcpy(p, op->create.symlink, size);
  41         kunmap_local(p);
  42         set_bit(AFS_VNODE_DIR_READ, &vnode->flags);
  43         netfs_single_mark_inode_dirty(&vnode->netfs.inode);
  44 }
  45
  46 static void afs_put_link(void *arg)
  47 {
  48         struct folio *folio = virt_to_folio(arg);
  49
  50         kunmap_local(arg);
  51         folio_put(folio);
  52 }
  53
  54 const char *afs_get_link(struct dentry *dentry, struct inode *inode,
  55                          struct delayed_call *callback)
  56 {
  57         struct afs_vnode *vnode = AFS_FS_I(inode);
  58         struct folio *folio;
  59         char *content;
  60         ssize_t ret;
  61
  62         if (!dentry) {
  63                 /* RCU pathwalk. */
  64                 if (!test_bit(AFS_VNODE_DIR_READ, &vnode->flags) || !afs_check_validity(vnode))
  65                         return ERR_PTR(-ECHILD);
  66                 goto good;
  67         }
  68
  69         if (test_bit(AFS_VNODE_DIR_READ, &vnode->flags))
  70                 goto fetch;
  71
  72         ret = afs_validate(vnode, NULL);
  73         if (ret < 0)
  74                 return ERR_PTR(ret);
  75
  76         if (!test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&
  77             test_bit(AFS_VNODE_DIR_READ, &vnode->flags))
  78                 goto good;
  79
  80 fetch:
  81         ret = afs_read_single(vnode, NULL);
  82         if (ret < 0)
  83                 return ERR_PTR(ret);
  84         set_bit(AFS_VNODE_DIR_READ, &vnode->flags);
  85
  86 good:
  87         folio = folioq_folio(vnode->directory, 0);
  88         folio_get(folio);
  89         content = kmap_local_folio(folio, 0);
  90         set_delayed_call(callback, afs_put_link, content);
  91         return content;
  92 }
  93
  94 int afs_readlink(struct dentry *dentry, char __user *buffer, int buflen)
  95 {
  96         DEFINE_DELAYED_CALL(done);
  97         const char *content;
  98         int len;
  99
 100         content = afs_get_link(dentry, d_inode(dentry), &done);
 101         if (IS_ERR(content)) {
 102                 do_delayed_call(&done);
 103                 return PTR_ERR(content);
 104         }
 105
 106         len = umin(strlen(content), buflen);
 107         if (copy_to_user(buffer, content, len))
 108                 len = -EFAULT;
 109         do_delayed_call(&done);
 110         return len;
 111 }
 112
 113 static const struct inode_operations afs_symlink_inode_operations = {
 114         .get_link       = afs_get_link,
 115         .readlink       = afs_readlink,
 116 };
 117
 118 static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode)
 119 {
 120         static unsigned long once_only;
 121
 122         pr_warn("kAFS: AFS vnode with undefined type %u\n", vnode->status.type);
 123         pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n",
 124                 vnode->status.abort_code,
 125                 vnode->status.mode,
 126                 vnode->status.size,
 127                 vnode->status.data_version);
 128         pr_warn("kAFS: vnode %llx:%llx:%x\n",
 129                 vnode->fid.vid,
 130                 vnode->fid.vnode,
 131                 vnode->fid.unique);
 132         if (parent_vnode)
 133                 pr_warn("kAFS: dir %llx:%llx:%x\n",
 134                         parent_vnode->fid.vid,
 135                         parent_vnode->fid.vnode,
 136                         parent_vnode->fid.unique);
 137
 138         if (!test_and_set_bit(0, &once_only))
 139                 dump_stack();
 140 }
 141
 142 /*
 143  * Set parameters for the netfs library
 144  */
 145 static void afs_set_netfs_context(struct afs_vnode *vnode)
 146 {
 147         netfs_inode_init(&vnode->netfs, &afs_req_ops, true);
 148 }
 149
 150 /*
 151  * Initialise an inode from the vnode status.
 152  */
 153 static int afs_inode_init_from_status(struct afs_operation *op,
 154                                       struct afs_vnode_param *vp,
 155                                       struct afs_vnode *vnode)
 156 {
 157         struct afs_file_status *status = &vp->scb.status;
 158         struct inode *inode = AFS_VNODE_TO_I(vnode);
 159         struct timespec64 t;
 160
 161         _enter("{%llx:%llu.%u} %s",
 162                vp->fid.vid, vp->fid.vnode, vp->fid.unique,
 163                op->type ? op->type->name : "???");
 164
 165         _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
 166                status->type,
 167                status->nlink,
 168                (unsigned long long) status->size,
 169                status->data_version,
 170                status->mode);
 171
 172         write_seqlock(&vnode->cb_lock);
 173
 174         vnode->cb_v_check = op->cb_v_break;
 175         vnode->status = *status;
 176
 177         t = status->mtime_client;
 178         inode_set_ctime_to_ts(inode, t);
 179         inode_set_mtime_to_ts(inode, t);
 180         inode_set_atime_to_ts(inode, t);
 181         inode->i_flags |= S_NOATIME;
 182         inode->i_uid = make_kuid(&init_user_ns, status->owner);
 183         inode->i_gid = make_kgid(&init_user_ns, status->group);
 184         set_nlink(&vnode->netfs.inode, status->nlink);
 185
 186         switch (status->type) {
 187         case AFS_FTYPE_FILE:
 188                 inode->i_mode   = S_IFREG | (status->mode & S_IALLUGO);
 189                 inode->i_op     = &afs_file_inode_operations;
 190                 inode->i_fop    = &afs_file_operations;
 191                 inode->i_mapping->a_ops = &afs_file_aops;
 192                 mapping_set_large_folios(inode->i_mapping);
 193                 break;
 194         case AFS_FTYPE_DIR:
 195                 inode->i_mode   = S_IFDIR |  (status->mode & S_IALLUGO);
 196                 inode->i_op     = &afs_dir_inode_operations;
 197                 inode->i_fop    = &afs_dir_file_operations;
 198                 inode->i_mapping->a_ops = &afs_dir_aops;
 199                 __set_bit(NETFS_ICTX_SINGLE_NO_UPLOAD, &vnode->netfs.flags);
 200                 /* Assume locally cached directory data will be valid. */
 201                 __set_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
 202                 break;
 203         case AFS_FTYPE_SYMLINK:
 204                 /* Symlinks with a mode of 0644 are actually mountpoints. */
 205                 if ((status->mode & 0777) == 0644) {
 206                         inode->i_flags |= S_AUTOMOUNT;
 207
 208                         set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
 209
 210                         inode->i_mode   = S_IFDIR | 0555;
 211                         inode->i_op     = &afs_mntpt_inode_operations;
 212                         inode->i_fop    = &afs_mntpt_file_operations;
 213                 } else {
 214                         inode->i_mode   = S_IFLNK | status->mode;
 215                         inode->i_op     = &afs_symlink_inode_operations;
 216                 }
 217                 inode->i_mapping->a_ops = &afs_dir_aops;
 218                 inode_nohighmem(inode);
 219                 mapping_set_release_always(inode->i_mapping);
 220                 break;
 221         default:
 222                 dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL);
 223                 write_sequnlock(&vnode->cb_lock);
 224                 return afs_protocol_error(NULL, afs_eproto_file_type);
 225         }
 226
 227         afs_set_i_size(vnode, status->size);
 228         afs_set_netfs_context(vnode);
 229
 230         vnode->invalid_before   = status->data_version;
 231         trace_afs_set_dv(vnode, status->data_version);
 232         inode_set_iversion_raw(&vnode->netfs.inode, status->data_version);
 233
 234         if (!vp->scb.have_cb) {
 235                 /* it's a symlink we just created (the fileserver
 236                  * didn't give us a callback) */
 237                 afs_clear_cb_promise(vnode, afs_cb_promise_set_new_symlink);
 238         } else {
 239                 vnode->cb_server = op->server;
 240                 afs_set_cb_promise(vnode, vp->scb.callback.expires_at,
 241                                    afs_cb_promise_set_new_inode);
 242         }
 243
 244         write_sequnlock(&vnode->cb_lock);
 245         return 0;
 246 }
 247
 248 /*
 249  * Update the core inode struct from a returned status record.
 250  */
 251 static void afs_apply_status(struct afs_operation *op,
 252                              struct afs_vnode_param *vp)
 253 {
 254         struct afs_file_status *status = &vp->scb.status;
 255         struct afs_vnode *vnode = vp->vnode;
 256         struct inode *inode = &vnode->netfs.inode;
 257         struct timespec64 t;
 258         umode_t mode;
 259         bool unexpected_jump = false;
 260         bool data_changed = false;
 261         bool change_size = vp->set_size;
 262
 263         _enter("{%llx:%llu.%u} %s",
 264                vp->fid.vid, vp->fid.vnode, vp->fid.unique,
 265                op->type ? op->type->name : "???");
 266
 267         BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));
 268
 269         if (status->type != vnode->status.type) {
 270                 pr_warn("Vnode %llx:%llx:%x changed type %u to %u\n",
 271                         vnode->fid.vid,
 272                         vnode->fid.vnode,
 273                         vnode->fid.unique,
 274                         status->type, vnode->status.type);
 275                 afs_protocol_error(NULL, afs_eproto_bad_status);
 276                 return;
 277         }
 278
 279         if (status->nlink != vnode->status.nlink)
 280                 set_nlink(inode, status->nlink);
 281
 282         if (status->owner != vnode->status.owner)
 283                 inode->i_uid = make_kuid(&init_user_ns, status->owner);
 284
 285         if (status->group != vnode->status.group)
 286                 inode->i_gid = make_kgid(&init_user_ns, status->group);
 287
 288         if (status->mode != vnode->status.mode) {
 289                 mode = inode->i_mode;
 290                 mode &= ~S_IALLUGO;
 291                 mode |= status->mode & S_IALLUGO;
 292                 WRITE_ONCE(inode->i_mode, mode);
 293         }
 294
 295         t = status->mtime_client;
 296         inode_set_mtime_to_ts(inode, t);
 297         if (vp->update_ctime)
 298                 inode_set_ctime_to_ts(inode, op->ctime);
 299
 300         if (vnode->status.data_version != status->data_version) {
 301                 trace_afs_set_dv(vnode, status->data_version);
 302                 data_changed = true;
 303         }
 304
 305         vnode->status = *status;
 306
 307         if (vp->dv_before + vp->dv_delta != status->data_version) {
 308                 trace_afs_dv_mismatch(vnode, vp->dv_before, vp->dv_delta,
 309                                       status->data_version);
 310
 311                 if (vnode->cb_ro_snapshot == atomic_read(&vnode->volume->cb_ro_snapshot) &&
 312                     atomic64_read(&vnode->cb_expires_at) != AFS_NO_CB_PROMISE)
 313                         pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s (op=%x)\n",
 314                                 vnode->fid.vid, vnode->fid.vnode,
 315                                 (unsigned long long)vp->dv_before + vp->dv_delta,
 316                                 (unsigned long long)status->data_version,
 317                                 op->type ? op->type->name : "???",
 318                                 op->debug_id);
 319
 320                 vnode->invalid_before = status->data_version;
 321                 if (vnode->status.type == AFS_FTYPE_DIR)
 322                         afs_invalidate_dir(vnode, afs_dir_invalid_dv_mismatch);
 323                 else
 324                         set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
 325                 change_size = true;
 326                 data_changed = true;
 327                 unexpected_jump = true;
 328         } else if (vnode->status.type == AFS_FTYPE_DIR) {
 329                 /* Expected directory change is handled elsewhere so
 330                  * that we can locally edit the directory and save on a
 331                  * download.
 332                  */
 333                 if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
 334                         data_changed = false;
 335                 change_size = true;
 336         }
 337
 338         if (data_changed) {
 339                 inode_set_iversion_raw(inode, status->data_version);
 340
 341                 /* Only update the size if the data version jumped.  If the
 342                  * file is being modified locally, then we might have our own
 343                  * idea of what the size should be that's not the same as
 344                  * what's on the server.
 345                  */
 346                 vnode->netfs.remote_i_size = status->size;
 347                 if (change_size || status->size > i_size_read(inode)) {
 348                         afs_set_i_size(vnode, status->size);
 349                         if (unexpected_jump)
 350                                 vnode->netfs.zero_point = status->size;
 351                         inode_set_ctime_to_ts(inode, t);
 352                         inode_set_atime_to_ts(inode, t);
 353                 }
 354                 if (op->ops == &afs_fetch_data_operation)
 355                         op->fetch.subreq->rreq->i_size = status->size;
 356         }
 357 }
 358
 359 /*
 360  * Apply a callback to a vnode.
 361  */
 362 static void afs_apply_callback(struct afs_operation *op,
 363                                struct afs_vnode_param *vp)
 364 {
 365         struct afs_callback *cb = &vp->scb.callback;
 366         struct afs_vnode *vnode = vp->vnode;
 367
 368         if (!afs_cb_is_broken(vp->cb_break_before, vnode)) {
 369                 if (op->volume->type == AFSVL_RWVOL)
 370                         vnode->cb_server = op->server;
 371                 afs_set_cb_promise(vnode, cb->expires_at, afs_cb_promise_set_apply_cb);
 372         }
 373 }
 374
 375 /*
 376  * Apply the received status and callback to an inode all in the same critical
 377  * section to avoid races with afs_validate().
 378  */
 379 void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp)
 380 {
 381         struct afs_vnode *vnode = vp->vnode;
 382
 383         _enter("");
 384
 385         write_seqlock(&vnode->cb_lock);
 386
 387         if (vp->scb.have_error) {
 388                 /* A YFS server will return this from RemoveFile2 and AFS and
 389                  * YFS will return this from InlineBulkStatus.
 390                  */
 391                 if (vp->scb.status.abort_code == VNOVNODE) {
 392                         set_bit(AFS_VNODE_DELETED, &vnode->flags);
 393                         clear_nlink(&vnode->netfs.inode);
 394                         __afs_break_callback(vnode, afs_cb_break_for_deleted);
 395                         op->flags &= ~AFS_OPERATION_DIR_CONFLICT;
 396                 }
 397         } else if (vp->scb.have_status) {
 398                 if (vp->speculative &&
 399                     (test_bit(AFS_VNODE_MODIFYING, &vnode->flags) ||
 400                      vp->dv_before != vnode->status.data_version))
 401                         /* Ignore the result of a speculative bulk status fetch
 402                          * if it splits around a modification op, thereby
 403                          * appearing to regress the data version.
 404                          */
 405                         goto out;
 406                 afs_apply_status(op, vp);
 407                 if (vp->scb.have_cb)
 408                         afs_apply_callback(op, vp);
 409         } else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {
 410                 drop_nlink(&vnode->netfs.inode);
 411                 if (vnode->netfs.inode.i_nlink == 0) {
 412                         set_bit(AFS_VNODE_DELETED, &vnode->flags);
 413                         __afs_break_callback(vnode, afs_cb_break_for_deleted);
 414                 }
 415         }
 416
 417 out:
 418         write_sequnlock(&vnode->cb_lock);
 419
 420         if (vp->scb.have_status)
 421                 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
 422 }
 423
 424 static void afs_fetch_status_success(struct afs_operation *op)
 425 {
 426         struct afs_vnode_param *vp = &op->file[op->fetch_status.which];
 427         struct afs_vnode *vnode = vp->vnode;
 428         int ret;
 429
 430         if (vnode->netfs.inode.i_state & I_NEW) {
 431                 ret = afs_inode_init_from_status(op, vp, vnode);
 432                 afs_op_set_error(op, ret);
 433                 if (ret == 0)
 434                         afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
 435         } else {
 436                 afs_vnode_commit_status(op, vp);
 437         }
 438 }
 439
 440 const struct afs_operation_ops afs_fetch_status_operation = {
 441         .issue_afs_rpc  = afs_fs_fetch_status,
 442         .issue_yfs_rpc  = yfs_fs_fetch_status,
 443         .success        = afs_fetch_status_success,
 444         .aborted        = afs_check_for_remote_deletion,
 445 };
 446
 447 /*
 448  * Fetch file status from the volume.
 449  */
 450 int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
 451                      afs_access_t *_caller_access)
 452 {
 453         struct afs_operation *op;
 454
 455         _enter("%s,{%llx:%llu.%u,S=%lx}",
 456                vnode->volume->name,
 457                vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
 458                vnode->flags);
 459
 460         op = afs_alloc_operation(key, vnode->volume);
 461         if (IS_ERR(op))
 462                 return PTR_ERR(op);
 463
 464         afs_op_set_vnode(op, 0, vnode);
 465
 466         op->nr_files    = 1;
 467         op->ops         = &afs_fetch_status_operation;
 468         afs_begin_vnode_operation(op);
 469         afs_wait_for_operation(op);
 470
 471         if (_caller_access)
 472                 *_caller_access = op->file[0].scb.status.caller_access;
 473         return afs_put_operation(op);
 474 }
 475
 476 /*
 477  * ilookup() comparator
 478  */
 479 int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)
 480 {
 481         struct afs_vnode *vnode = AFS_FS_I(inode);
 482         struct afs_fid *fid = opaque;
 483
 484         return (fid->vnode == vnode->fid.vnode &&
 485                 fid->vnode_hi == vnode->fid.vnode_hi &&
 486                 fid->unique == vnode->fid.unique);
 487 }
 488
 489 /*
 490  * iget5() comparator
 491  */
 492 static int afs_iget5_test(struct inode *inode, void *opaque)
 493 {
 494         struct afs_vnode_param *vp = opaque;
 495         //struct afs_vnode *vnode = AFS_FS_I(inode);
 496
 497         return afs_ilookup5_test_by_fid(inode, &vp->fid);
 498 }
 499
 500 /*
 501  * iget5() inode initialiser
 502  */
 503 static int afs_iget5_set(struct inode *inode, void *opaque)
 504 {
 505         struct afs_vnode_param *vp = opaque;
 506         struct afs_super_info *as = AFS_FS_S(inode->i_sb);
 507         struct afs_vnode *vnode = AFS_FS_I(inode);
 508
 509         vnode->volume           = as->volume;
 510         vnode->fid              = vp->fid;
 511
 512         /* YFS supports 96-bit vnode IDs, but Linux only supports
 513          * 64-bit inode numbers.
 514          */
 515         inode->i_ino            = vnode->fid.vnode;
 516         inode->i_generation     = vnode->fid.unique;
 517         return 0;
 518 }
 519
 520 /*
 521  * Get a cache cookie for an inode.
 522  */
 523 static void afs_get_inode_cache(struct afs_vnode *vnode)
 524 {
 525 #ifdef CONFIG_AFS_FSCACHE
 526         struct {
 527                 __be32 vnode_id;
 528                 __be32 unique;
 529                 __be32 vnode_id_ext[2]; /* Allow for a 96-bit key */
 530         } __packed key;
 531         struct afs_vnode_cache_aux aux;
 532
 533         if (vnode->status.type != AFS_FTYPE_FILE &&
 534             vnode->status.type != AFS_FTYPE_DIR &&
 535             vnode->status.type != AFS_FTYPE_SYMLINK) {
 536                 vnode->netfs.cache = NULL;
 537                 return;
 538         }
 539
 540         key.vnode_id            = htonl(vnode->fid.vnode);
 541         key.unique              = htonl(vnode->fid.unique);
 542         key.vnode_id_ext[0]     = htonl(vnode->fid.vnode >> 32);
 543         key.vnode_id_ext[1]     = htonl(vnode->fid.vnode_hi);
 544         afs_set_cache_aux(vnode, &aux);
 545
 546         afs_vnode_set_cache(vnode,
 547                             fscache_acquire_cookie(
 548                                     vnode->volume->cache,
 549                                     vnode->status.type == AFS_FTYPE_FILE ?
 550                                     0 : FSCACHE_ADV_SINGLE_CHUNK,
 551                                     &key, sizeof(key),
 552                                     &aux, sizeof(aux),
 553                                     i_size_read(&vnode->netfs.inode)));
 554 #endif
 555 }
 556
 557 /*
 558  * inode retrieval
 559  */
 560 struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)
 561 {
 562         struct afs_vnode_param *dvp = &op->file[0];
 563         struct super_block *sb = dvp->vnode->netfs.inode.i_sb;
 564         struct afs_vnode *vnode;
 565         struct inode *inode;
 566         int ret;
 567
 568         _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);
 569
 570         inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);
 571         if (!inode) {
 572                 _leave(" = -ENOMEM");
 573                 return ERR_PTR(-ENOMEM);
 574         }
 575
 576         vnode = AFS_FS_I(inode);
 577
 578         _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
 579                inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);
 580
 581         /* deal with an existing inode */
 582         if (!(inode->i_state & I_NEW)) {
 583                 _leave(" = %p", inode);
 584                 return inode;
 585         }
 586
 587         ret = afs_inode_init_from_status(op, vp, vnode);
 588         if (ret < 0)
 589                 goto bad_inode;
 590
 591         afs_get_inode_cache(vnode);
 592
 593         /* success */
 594         clear_bit(AFS_VNODE_UNSET, &vnode->flags);
 595         unlock_new_inode(inode);
 596         _leave(" = %p", inode);
 597         return inode;
 598
 599         /* failure */
 600 bad_inode:
 601         iget_failed(inode);
 602         _leave(" = %d [bad]", ret);
 603         return ERR_PTR(ret);
 604 }
 605
 606 static int afs_iget5_set_root(struct inode *inode, void *opaque)
 607 {
 608         struct afs_super_info *as = AFS_FS_S(inode->i_sb);
 609         struct afs_vnode *vnode = AFS_FS_I(inode);
 610
 611         vnode->volume           = as->volume;
 612         vnode->fid.vid          = as->volume->vid;
 613         vnode->fid.vnode        = 1;
 614         vnode->fid.unique       = 1;
 615         inode->i_ino            = 1;
 616         inode->i_generation     = 1;
 617         return 0;
 618 }
 619
 620 /*
 621  * Set up the root inode for a volume.  This is always vnode 1, unique 1 within
 622  * the volume.
 623  */
 624 struct inode *afs_root_iget(struct super_block *sb, struct key *key)
 625 {
 626         struct afs_super_info *as = AFS_FS_S(sb);
 627         struct afs_operation *op;
 628         struct afs_vnode *vnode;
 629         struct inode *inode;
 630         int ret;
 631
 632         _enter(",{%llx},,", as->volume->vid);
 633
 634         inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);
 635         if (!inode) {
 636                 _leave(" = -ENOMEM");
 637                 return ERR_PTR(-ENOMEM);
 638         }
 639
 640         _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);
 641
 642         BUG_ON(!(inode->i_state & I_NEW));
 643
 644         vnode = AFS_FS_I(inode);
 645         vnode->cb_v_check = atomic_read(&as->volume->cb_v_break);
 646         afs_set_netfs_context(vnode);
 647
 648         op = afs_alloc_operation(key, as->volume);
 649         if (IS_ERR(op)) {
 650                 ret = PTR_ERR(op);
 651                 goto error;
 652         }
 653
 654         afs_op_set_vnode(op, 0, vnode);
 655
 656         op->nr_files    = 1;
 657         op->ops         = &afs_fetch_status_operation;
 658         ret = afs_do_sync_operation(op);
 659         if (ret < 0)
 660                 goto error;
 661
 662         afs_get_inode_cache(vnode);
 663
 664         clear_bit(AFS_VNODE_UNSET, &vnode->flags);
 665         unlock_new_inode(inode);
 666         _leave(" = %p", inode);
 667         return inode;
 668
 669 error:
 670         iget_failed(inode);
 671         _leave(" = %d [bad]", ret);
 672         return ERR_PTR(ret);
 673 }
 674
 675 /*
 676  * read the attributes of an inode
 677  */
 678 int afs_getattr(struct mnt_idmap *idmap, const struct path *path,
 679                 struct kstat *stat, u32 request_mask, unsigned int query_flags)
 680 {
 681         struct inode *inode = d_inode(path->dentry);
 682         struct afs_vnode *vnode = AFS_FS_I(inode);
 683         struct key *key;
 684         int ret, seq;
 685
 686         _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
 687
 688         if (vnode->volume &&
 689             !(query_flags & AT_STATX_DONT_SYNC) &&
 690             atomic64_read(&vnode->cb_expires_at) == AFS_NO_CB_PROMISE) {
 691                 key = afs_request_key(vnode->volume->cell);
 692                 if (IS_ERR(key))
 693                         return PTR_ERR(key);
 694                 ret = afs_validate(vnode, key);
 695                 key_put(key);
 696                 if (ret < 0)
 697                         return ret;
 698         }
 699
 700         do {
 701                 seq = read_seqbegin(&vnode->cb_lock);
 702                 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
 703                 if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
 704                     stat->nlink > 0)
 705                         stat->nlink -= 1;
 706
 707                 /* Lie about the size of directories.  We maintain a locally
 708                  * edited copy and may make different allocation decisions on
 709                  * it, but we need to give userspace the server's size.
 710                  */
 711                 if (S_ISDIR(inode->i_mode))
 712                         stat->size = vnode->netfs.remote_i_size;
 713         } while (read_seqretry(&vnode->cb_lock, seq));
 714
 715         return 0;
 716 }
 717
 718 /*
 719  * discard an AFS inode
 720  */
 721 int afs_drop_inode(struct inode *inode)
 722 {
 723         _enter("");
 724
 725         if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
 726                 return generic_delete_inode(inode);
 727         else
 728                 return generic_drop_inode(inode);
 729 }
 730
 731 /*
 732  * clear an AFS inode
 733  */
 734 void afs_evict_inode(struct inode *inode)
 735 {
 736         struct afs_vnode_cache_aux aux;
 737         struct afs_super_info *sbi = AFS_FS_S(inode->i_sb);
 738         struct afs_vnode *vnode = AFS_FS_I(inode);
 739
 740         _enter("{%llx:%llu.%d}",
 741                vnode->fid.vid,
 742                vnode->fid.vnode,
 743                vnode->fid.unique);
 744
 745         _debug("CLEAR INODE %p", inode);
 746
 747         ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
 748
 749         if ((S_ISDIR(inode->i_mode) ||
 750              S_ISLNK(inode->i_mode)) &&
 751             (inode->i_state & I_DIRTY) &&
 752             !sbi->dyn_root) {
 753                 struct writeback_control wbc = {
 754                         .sync_mode = WB_SYNC_ALL,
 755                         .for_sync = true,
 756                         .range_end = LLONG_MAX,
 757                 };
 758
 759                 afs_single_writepages(inode->i_mapping, &wbc);
 760         }
 761
 762         netfs_wait_for_outstanding_io(inode);
 763         truncate_inode_pages_final(&inode->i_data);
 764         netfs_free_folioq_buffer(vnode->directory);
 765
 766         afs_set_cache_aux(vnode, &aux);
 767         netfs_clear_inode_writeback(inode, &aux);
 768         clear_inode(inode);
 769
 770         while (!list_empty(&vnode->wb_keys)) {
 771                 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
 772                                                     struct afs_wb_key, vnode_link);
 773                 list_del(&wbk->vnode_link);
 774                 afs_put_wb_key(wbk);
 775         }
 776
 777         fscache_relinquish_cookie(afs_vnode_cache(vnode),
 778                                   test_bit(AFS_VNODE_DELETED, &vnode->flags));
 779
 780         afs_prune_wb_keys(vnode);
 781         afs_put_permits(rcu_access_pointer(vnode->permit_cache));
 782         key_put(vnode->silly_key);
 783         vnode->silly_key = NULL;
 784         key_put(vnode->lock_key);
 785         vnode->lock_key = NULL;
 786         _leave("");
 787 }
 788
 789 static void afs_setattr_success(struct afs_operation *op)
 790 {
 791         struct afs_vnode_param *vp = &op->file[0];
 792         struct inode *inode = &vp->vnode->netfs.inode;
 793         loff_t old_i_size = i_size_read(inode);
 794
 795         op->setattr.old_i_size = old_i_size;
 796         afs_vnode_commit_status(op, vp);
 797         /* inode->i_size has now been changed. */
 798
 799         if (op->setattr.attr->ia_valid & ATTR_SIZE) {
 800                 loff_t size = op->setattr.attr->ia_size;
 801                 if (size > old_i_size)
 802                         pagecache_isize_extended(inode, old_i_size, size);
 803         }
 804 }
 805
 806 static void afs_setattr_edit_file(struct afs_operation *op)
 807 {
 808         struct afs_vnode_param *vp = &op->file[0];
 809         struct afs_vnode *vnode = vp->vnode;
 810         struct inode *inode = &vnode->netfs.inode;
 811
 812         if (op->setattr.attr->ia_valid & ATTR_SIZE) {
 813                 loff_t size = op->setattr.attr->ia_size;
 814                 loff_t old = op->setattr.old_i_size;
 815
 816                 /* Note: inode->i_size was updated by afs_apply_status() inside
 817                  * the I/O and callback locks.
 818                  */
 819
 820                 if (size != old) {
 821                         truncate_pagecache(inode, size);
 822                         netfs_resize_file(&vnode->netfs, size, true);
 823                         fscache_resize_cookie(afs_vnode_cache(vnode), size);
 824                 }
 825         }
 826 }
 827
 828 static const struct afs_operation_ops afs_setattr_operation = {
 829         .issue_afs_rpc  = afs_fs_setattr,
 830         .issue_yfs_rpc  = yfs_fs_setattr,
 831         .success        = afs_setattr_success,
 832         .edit_dir       = afs_setattr_edit_file,
 833 };
 834
 835 /*
 836  * set the attributes of an inode
 837  */
 838 int afs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 839                 struct iattr *attr)
 840 {
 841         const unsigned int supported =
 842                 ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
 843                 ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET | ATTR_TOUCH;
 844         struct afs_operation *op;
 845         struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
 846         struct inode *inode = &vnode->netfs.inode;
 847         loff_t i_size;
 848         int ret;
 849
 850         _enter("{%llx:%llu},{n=%pd},%x",
 851                vnode->fid.vid, vnode->fid.vnode, dentry,
 852                attr->ia_valid);
 853
 854         if (!(attr->ia_valid & supported)) {
 855                 _leave(" = 0 [unsupported]");
 856                 return 0;
 857         }
 858
 859         i_size = i_size_read(inode);
 860         if (attr->ia_valid & ATTR_SIZE) {
 861                 if (!S_ISREG(inode->i_mode))
 862                         return -EISDIR;
 863
 864                 ret = inode_newsize_ok(inode, attr->ia_size);
 865                 if (ret)
 866                         return ret;
 867
 868                 if (attr->ia_size == i_size)
 869                         attr->ia_valid &= ~ATTR_SIZE;
 870         }
 871
 872         fscache_use_cookie(afs_vnode_cache(vnode), true);
 873
 874         /* Prevent any new writebacks from starting whilst we do this. */
 875         down_write(&vnode->validate_lock);
 876
 877         if ((attr->ia_valid & ATTR_SIZE) && S_ISREG(inode->i_mode)) {
 878                 loff_t size = attr->ia_size;
 879
 880                 /* Wait for any outstanding writes to the server to complete */
 881                 loff_t from = min(size, i_size);
 882                 loff_t to = max(size, i_size);
 883                 ret = filemap_fdatawait_range(inode->i_mapping, from, to);
 884                 if (ret < 0)
 885                         goto out_unlock;
 886
 887                 /* Don't talk to the server if we're just shortening in-memory
 888                  * writes that haven't gone to the server yet.
 889                  */
 890                 if (!(attr->ia_valid & (supported & ~ATTR_SIZE & ~ATTR_MTIME)) &&
 891                     attr->ia_size < i_size &&
 892                     attr->ia_size > vnode->netfs.remote_i_size) {
 893                         truncate_setsize(inode, attr->ia_size);
 894                         netfs_resize_file(&vnode->netfs, size, false);
 895                         fscache_resize_cookie(afs_vnode_cache(vnode),
 896                                               attr->ia_size);
 897                         ret = 0;
 898                         goto out_unlock;
 899                 }
 900         }
 901
 902         op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
 903                                   afs_file_key(attr->ia_file) : NULL),
 904                                  vnode->volume);
 905         if (IS_ERR(op)) {
 906                 ret = PTR_ERR(op);
 907                 goto out_unlock;
 908         }
 909
 910         afs_op_set_vnode(op, 0, vnode);
 911         op->setattr.attr = attr;
 912
 913         if (attr->ia_valid & ATTR_SIZE) {
 914                 op->file[0].dv_delta = 1;
 915                 op->file[0].set_size = true;
 916         }
 917         op->ctime = attr->ia_ctime;
 918         op->file[0].update_ctime = 1;
 919         op->file[0].modification = true;
 920
 921         op->ops = &afs_setattr_operation;
 922         ret = afs_do_sync_operation(op);
 923
 924 out_unlock:
 925         up_write(&vnode->validate_lock);
 926         fscache_unuse_cookie(afs_vnode_cache(vnode), NULL, NULL);
 927         _leave(" = %d", ret);
 928         return ret;
 929 }