fs/btrfs/delayed-inode.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2011 Fujitsu.  All rights reserved.
   4  * Written by Miao Xie <[email protected]>
   5  */
   6
   7 #include <linux/slab.h>
   8 #include <linux/iversion.h>
   9 #include "delayed-inode.h"
  10 #include "disk-io.h"
  11 #include "transaction.h"
  12 #include "ctree.h"
  13 #include "qgroup.h"
  14
  15 #define BTRFS_DELAYED_WRITEBACK         512
  16 #define BTRFS_DELAYED_BACKGROUND        128
  17 #define BTRFS_DELAYED_BATCH             16
  18
  19 static struct kmem_cache *delayed_node_cache;
  20
  21 int __init btrfs_delayed_inode_init(void)
  22 {
  23         delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
  24                                         sizeof(struct btrfs_delayed_node),
  25                                         0,
  26                                         SLAB_MEM_SPREAD,
  27                                         NULL);
  28         if (!delayed_node_cache)
  29                 return -ENOMEM;
  30         return 0;
  31 }
  32
  33 void __cold btrfs_delayed_inode_exit(void)
  34 {
  35         kmem_cache_destroy(delayed_node_cache);
  36 }
  37
  38 static inline void btrfs_init_delayed_node(
  39                                 struct btrfs_delayed_node *delayed_node,
  40                                 struct btrfs_root *root, u64 inode_id)
  41 {
  42         delayed_node->root = root;
  43         delayed_node->inode_id = inode_id;
  44         refcount_set(&delayed_node->refs, 0);
  45         delayed_node->ins_root = RB_ROOT;
  46         delayed_node->del_root = RB_ROOT;
  47         mutex_init(&delayed_node->mutex);
  48         INIT_LIST_HEAD(&delayed_node->n_list);
  49         INIT_LIST_HEAD(&delayed_node->p_list);
  50 }
  51
  52 static inline int btrfs_is_continuous_delayed_item(
  53                                         struct btrfs_delayed_item *item1,
  54                                         struct btrfs_delayed_item *item2)
  55 {
  56         if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
  57             item1->key.objectid == item2->key.objectid &&
  58             item1->key.type == item2->key.type &&
  59             item1->key.offset + 1 == item2->key.offset)
  60                 return 1;
  61         return 0;
  62 }
  63
  64 static struct btrfs_delayed_node *btrfs_get_delayed_node(
  65                 struct btrfs_inode *btrfs_inode)
  66 {
  67         struct btrfs_root *root = btrfs_inode->root;
  68         u64 ino = btrfs_ino(btrfs_inode);
  69         struct btrfs_delayed_node *node;
  70
  71         node = READ_ONCE(btrfs_inode->delayed_node);
  72         if (node) {
  73                 refcount_inc(&node->refs);
  74                 return node;
  75         }
  76
  77         spin_lock(&root->inode_lock);
  78         node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
  79
  80         if (node) {
  81                 if (btrfs_inode->delayed_node) {
  82                         refcount_inc(&node->refs);      /* can be accessed */
  83                         BUG_ON(btrfs_inode->delayed_node != node);
  84                         spin_unlock(&root->inode_lock);
  85                         return node;
  86                 }
  87
  88                 /*
  89                  * It's possible that we're racing into the middle of removing
  90                  * this node from the radix tree.  In this case, the refcount
  91                  * was zero and it should never go back to one.  Just return
  92                  * NULL like it was never in the radix at all; our release
  93                  * function is in the process of removing it.
  94                  *
  95                  * Some implementations of refcount_inc refuse to bump the
  96                  * refcount once it has hit zero.  If we don't do this dance
  97                  * here, refcount_inc() may decide to just WARN_ONCE() instead
  98                  * of actually bumping the refcount.
  99                  *
 100                  * If this node is properly in the radix, we want to bump the
 101                  * refcount twice, once for the inode and once for this get
 102                  * operation.
 103                  */
 104                 if (refcount_inc_not_zero(&node->refs)) {
 105                         refcount_inc(&node->refs);
 106                         btrfs_inode->delayed_node = node;
 107                 } else {
 108                         node = NULL;
 109                 }
 110
 111                 spin_unlock(&root->inode_lock);
 112                 return node;
 113         }
 114         spin_unlock(&root->inode_lock);
 115
 116         return NULL;
 117 }
 118
 119 /* Will return either the node or PTR_ERR(-ENOMEM) */
 120 static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 121                 struct btrfs_inode *btrfs_inode)
 122 {
 123         struct btrfs_delayed_node *node;
 124         struct btrfs_root *root = btrfs_inode->root;
 125         u64 ino = btrfs_ino(btrfs_inode);
 126         int ret;
 127
 128 again:
 129         node = btrfs_get_delayed_node(btrfs_inode);
 130         if (node)
 131                 return node;
 132
 133         node = kmem_cache_zalloc(delayed_node_cache, GFP_NOFS);
 134         if (!node)
 135                 return ERR_PTR(-ENOMEM);
 136         btrfs_init_delayed_node(node, root, ino);
 137
 138         /* cached in the btrfs inode and can be accessed */
 139         refcount_set(&node->refs, 2);
 140
 141         ret = radix_tree_preload(GFP_NOFS);
 142         if (ret) {
 143                 kmem_cache_free(delayed_node_cache, node);
 144                 return ERR_PTR(ret);
 145         }
 146
 147         spin_lock(&root->inode_lock);
 148         ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
 149         if (ret == -EEXIST) {
 150                 spin_unlock(&root->inode_lock);
 151                 kmem_cache_free(delayed_node_cache, node);
 152                 radix_tree_preload_end();
 153                 goto again;
 154         }
 155         btrfs_inode->delayed_node = node;
 156         spin_unlock(&root->inode_lock);
 157         radix_tree_preload_end();
 158
 159         return node;
 160 }
 161
 162 /*
 163  * Call it when holding delayed_node->mutex
 164  *
 165  * If mod = 1, add this node into the prepared list.
 166  */
 167 static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
 168                                      struct btrfs_delayed_node *node,
 169                                      int mod)
 170 {
 171         spin_lock(&root->lock);
 172         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 173                 if (!list_empty(&node->p_list))
 174                         list_move_tail(&node->p_list, &root->prepare_list);
 175                 else if (mod)
 176                         list_add_tail(&node->p_list, &root->prepare_list);
 177         } else {
 178                 list_add_tail(&node->n_list, &root->node_list);
 179                 list_add_tail(&node->p_list, &root->prepare_list);
 180                 refcount_inc(&node->refs);      /* inserted into list */
 181                 root->nodes++;
 182                 set_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 183         }
 184         spin_unlock(&root->lock);
 185 }
 186
 187 /* Call it when holding delayed_node->mutex */
 188 static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
 189                                        struct btrfs_delayed_node *node)
 190 {
 191         spin_lock(&root->lock);
 192         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 193                 root->nodes--;
 194                 refcount_dec(&node->refs);      /* not in the list */
 195                 list_del_init(&node->n_list);
 196                 if (!list_empty(&node->p_list))
 197                         list_del_init(&node->p_list);
 198                 clear_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 199         }
 200         spin_unlock(&root->lock);
 201 }
 202
 203 static struct btrfs_delayed_node *btrfs_first_delayed_node(
 204                         struct btrfs_delayed_root *delayed_root)
 205 {
 206         struct list_head *p;
 207         struct btrfs_delayed_node *node = NULL;
 208
 209         spin_lock(&delayed_root->lock);
 210         if (list_empty(&delayed_root->node_list))
 211                 goto out;
 212
 213         p = delayed_root->node_list.next;
 214         node = list_entry(p, struct btrfs_delayed_node, n_list);
 215         refcount_inc(&node->refs);
 216 out:
 217         spin_unlock(&delayed_root->lock);
 218
 219         return node;
 220 }
 221
 222 static struct btrfs_delayed_node *btrfs_next_delayed_node(
 223                                                 struct btrfs_delayed_node *node)
 224 {
 225         struct btrfs_delayed_root *delayed_root;
 226         struct list_head *p;
 227         struct btrfs_delayed_node *next = NULL;
 228
 229         delayed_root = node->root->fs_info->delayed_root;
 230         spin_lock(&delayed_root->lock);
 231         if (!test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 232                 /* not in the list */
 233                 if (list_empty(&delayed_root->node_list))
 234                         goto out;
 235                 p = delayed_root->node_list.next;
 236         } else if (list_is_last(&node->n_list, &delayed_root->node_list))
 237                 goto out;
 238         else
 239                 p = node->n_list.next;
 240
 241         next = list_entry(p, struct btrfs_delayed_node, n_list);
 242         refcount_inc(&next->refs);
 243 out:
 244         spin_unlock(&delayed_root->lock);
 245
 246         return next;
 247 }
 248
 249 static void __btrfs_release_delayed_node(
 250                                 struct btrfs_delayed_node *delayed_node,
 251                                 int mod)
 252 {
 253         struct btrfs_delayed_root *delayed_root;
 254
 255         if (!delayed_node)
 256                 return;
 257
 258         delayed_root = delayed_node->root->fs_info->delayed_root;
 259
 260         mutex_lock(&delayed_node->mutex);
 261         if (delayed_node->count)
 262                 btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
 263         else
 264                 btrfs_dequeue_delayed_node(delayed_root, delayed_node);
 265         mutex_unlock(&delayed_node->mutex);
 266
 267         if (refcount_dec_and_test(&delayed_node->refs)) {
 268                 struct btrfs_root *root = delayed_node->root;
 269
 270                 spin_lock(&root->inode_lock);
 271                 /*
 272                  * Once our refcount goes to zero, nobody is allowed to bump it
 273                  * back up.  We can delete it now.
 274                  */
 275                 ASSERT(refcount_read(&delayed_node->refs) == 0);
 276                 radix_tree_delete(&root->delayed_nodes_tree,
 277                                   delayed_node->inode_id);
 278                 spin_unlock(&root->inode_lock);
 279                 kmem_cache_free(delayed_node_cache, delayed_node);
 280         }
 281 }
 282
 283 static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 284 {
 285         __btrfs_release_delayed_node(node, 0);
 286 }
 287
 288 static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 289                                         struct btrfs_delayed_root *delayed_root)
 290 {
 291         struct list_head *p;
 292         struct btrfs_delayed_node *node = NULL;
 293
 294         spin_lock(&delayed_root->lock);
 295         if (list_empty(&delayed_root->prepare_list))
 296                 goto out;
 297
 298         p = delayed_root->prepare_list.next;
 299         list_del_init(p);
 300         node = list_entry(p, struct btrfs_delayed_node, p_list);
 301         refcount_inc(&node->refs);
 302 out:
 303         spin_unlock(&delayed_root->lock);
 304
 305         return node;
 306 }
 307
 308 static inline void btrfs_release_prepared_delayed_node(
 309                                         struct btrfs_delayed_node *node)
 310 {
 311         __btrfs_release_delayed_node(node, 1);
 312 }
 313
 314 static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
 315 {
 316         struct btrfs_delayed_item *item;
 317         item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
 318         if (item) {
 319                 item->data_len = data_len;
 320                 item->ins_or_del = 0;
 321                 item->bytes_reserved = 0;
 322                 item->delayed_node = NULL;
 323                 refcount_set(&item->refs, 1);
 324         }
 325         return item;
 326 }
 327
 328 /*
 329  * __btrfs_lookup_delayed_item - look up the delayed item by key
 330  * @delayed_node: pointer to the delayed node
 331  * @key:          the key to look up
 332  * @prev:         used to store the prev item if the right item isn't found
 333  * @next:         used to store the next item if the right item isn't found
 334  *
 335  * Note: if we don't find the right item, we will return the prev item and
 336  * the next item.
 337  */
 338 static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 339                                 struct rb_root *root,
 340                                 struct btrfs_key *key,
 341                                 struct btrfs_delayed_item **prev,
 342                                 struct btrfs_delayed_item **next)
 343 {
 344         struct rb_node *node, *prev_node = NULL;
 345         struct btrfs_delayed_item *delayed_item = NULL;
 346         int ret = 0;
 347
 348         node = root->rb_node;
 349
 350         while (node) {
 351                 delayed_item = rb_entry(node, struct btrfs_delayed_item,
 352                                         rb_node);
 353                 prev_node = node;
 354                 ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
 355                 if (ret < 0)
 356                         node = node->rb_right;
 357                 else if (ret > 0)
 358                         node = node->rb_left;
 359                 else
 360                         return delayed_item;
 361         }
 362
 363         if (prev) {
 364                 if (!prev_node)
 365                         *prev = NULL;
 366                 else if (ret < 0)
 367                         *prev = delayed_item;
 368                 else if ((node = rb_prev(prev_node)) != NULL) {
 369                         *prev = rb_entry(node, struct btrfs_delayed_item,
 370                                          rb_node);
 371                 } else
 372                         *prev = NULL;
 373         }
 374
 375         if (next) {
 376                 if (!prev_node)
 377                         *next = NULL;
 378                 else if (ret > 0)
 379                         *next = delayed_item;
 380                 else if ((node = rb_next(prev_node)) != NULL) {
 381                         *next = rb_entry(node, struct btrfs_delayed_item,
 382                                          rb_node);
 383                 } else
 384                         *next = NULL;
 385         }
 386         return NULL;
 387 }
 388
 389 static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
 390                                         struct btrfs_delayed_node *delayed_node,
 391                                         struct btrfs_key *key)
 392 {
 393         return __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
 394                                            NULL, NULL);
 395 }
 396
 397 static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 398                                     struct btrfs_delayed_item *ins,
 399                                     int action)
 400 {
 401         struct rb_node **p, *node;
 402         struct rb_node *parent_node = NULL;
 403         struct rb_root *root;
 404         struct btrfs_delayed_item *item;
 405         int cmp;
 406
 407         if (action == BTRFS_DELAYED_INSERTION_ITEM)
 408                 root = &delayed_node->ins_root;
 409         else if (action == BTRFS_DELAYED_DELETION_ITEM)
 410                 root = &delayed_node->del_root;
 411         else
 412                 BUG();
 413         p = &root->rb_node;
 414         node = &ins->rb_node;
 415
 416         while (*p) {
 417                 parent_node = *p;
 418                 item = rb_entry(parent_node, struct btrfs_delayed_item,
 419                                  rb_node);
 420
 421                 cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
 422                 if (cmp < 0)
 423                         p = &(*p)->rb_right;
 424                 else if (cmp > 0)
 425                         p = &(*p)->rb_left;
 426                 else
 427                         return -EEXIST;
 428         }
 429
 430         rb_link_node(node, parent_node, p);
 431         rb_insert_color(node, root);
 432         ins->delayed_node = delayed_node;
 433         ins->ins_or_del = action;
 434
 435         if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
 436             action == BTRFS_DELAYED_INSERTION_ITEM &&
 437             ins->key.offset >= delayed_node->index_cnt)
 438                         delayed_node->index_cnt = ins->key.offset + 1;
 439
 440         delayed_node->count++;
 441         atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 442         return 0;
 443 }
 444
 445 static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
 446                                               struct btrfs_delayed_item *item)
 447 {
 448         return __btrfs_add_delayed_item(node, item,
 449                                         BTRFS_DELAYED_INSERTION_ITEM);
 450 }
 451
 452 static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 453                                              struct btrfs_delayed_item *item)
 454 {
 455         return __btrfs_add_delayed_item(node, item,
 456                                         BTRFS_DELAYED_DELETION_ITEM);
 457 }
 458
 459 static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 460 {
 461         int seq = atomic_inc_return(&delayed_root->items_seq);
 462
 463         /* atomic_dec_return implies a barrier */
 464         if ((atomic_dec_return(&delayed_root->items) <
 465             BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0))
 466                 cond_wake_up_nomb(&delayed_root->wait);
 467 }
 468
 469 static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 470 {
 471         struct rb_root *root;
 472         struct btrfs_delayed_root *delayed_root;
 473
 474         delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
 475
 476         BUG_ON(!delayed_root);
 477         BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
 478                delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
 479
 480         if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
 481                 root = &delayed_item->delayed_node->ins_root;
 482         else
 483                 root = &delayed_item->delayed_node->del_root;
 484
 485         rb_erase(&delayed_item->rb_node, root);
 486         delayed_item->delayed_node->count--;
 487
 488         finish_one_item(delayed_root);
 489 }
 490
 491 static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 492 {
 493         if (item) {
 494                 __btrfs_remove_delayed_item(item);
 495                 if (refcount_dec_and_test(&item->refs))
 496                         kfree(item);
 497         }
 498 }
 499
 500 static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
 501                                         struct btrfs_delayed_node *delayed_node)
 502 {
 503         struct rb_node *p;
 504         struct btrfs_delayed_item *item = NULL;
 505
 506         p = rb_first(&delayed_node->ins_root);
 507         if (p)
 508                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 509
 510         return item;
 511 }
 512
 513 static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 514                                         struct btrfs_delayed_node *delayed_node)
 515 {
 516         struct rb_node *p;
 517         struct btrfs_delayed_item *item = NULL;
 518
 519         p = rb_first(&delayed_node->del_root);
 520         if (p)
 521                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 522
 523         return item;
 524 }
 525
 526 static struct btrfs_delayed_item *__btrfs_next_delayed_item(
 527                                                 struct btrfs_delayed_item *item)
 528 {
 529         struct rb_node *p;
 530         struct btrfs_delayed_item *next = NULL;
 531
 532         p = rb_next(&item->rb_node);
 533         if (p)
 534                 next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 535
 536         return next;
 537 }
 538
 539 static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 540                                                struct btrfs_root *root,
 541                                                struct btrfs_delayed_item *item)
 542 {
 543         struct btrfs_block_rsv *src_rsv;
 544         struct btrfs_block_rsv *dst_rsv;
 545         struct btrfs_fs_info *fs_info = root->fs_info;
 546         u64 num_bytes;
 547         int ret;
 548
 549         if (!trans->bytes_reserved)
 550                 return 0;
 551
 552         src_rsv = trans->block_rsv;
 553         dst_rsv = &fs_info->delayed_block_rsv;
 554
 555         num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 556
 557         /*
 558          * Here we migrate space rsv from transaction rsv, since have already
 559          * reserved space when starting a transaction.  So no need to reserve
 560          * qgroup space here.
 561          */
 562         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 563         if (!ret) {
 564                 trace_btrfs_space_reservation(fs_info, "delayed_item",
 565                                               item->key.objectid,
 566                                               num_bytes, 1);
 567                 item->bytes_reserved = num_bytes;
 568         }
 569
 570         return ret;
 571 }
 572
 573 static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
 574                                                 struct btrfs_delayed_item *item)
 575 {
 576         struct btrfs_block_rsv *rsv;
 577         struct btrfs_fs_info *fs_info = root->fs_info;
 578
 579         if (!item->bytes_reserved)
 580                 return;
 581
 582         rsv = &fs_info->delayed_block_rsv;
 583         /*
 584          * Check btrfs_delayed_item_reserve_metadata() to see why we don't need
 585          * to release/reserve qgroup space.
 586          */
 587         trace_btrfs_space_reservation(fs_info, "delayed_item",
 588                                       item->key.objectid, item->bytes_reserved,
 589                                       0);
 590         btrfs_block_rsv_release(fs_info, rsv,
 591                                 item->bytes_reserved);
 592 }
 593
 594 static int btrfs_delayed_inode_reserve_metadata(
 595                                         struct btrfs_trans_handle *trans,
 596                                         struct btrfs_root *root,
 597                                         struct btrfs_inode *inode,
 598                                         struct btrfs_delayed_node *node)
 599 {
 600         struct btrfs_fs_info *fs_info = root->fs_info;
 601         struct btrfs_block_rsv *src_rsv;
 602         struct btrfs_block_rsv *dst_rsv;
 603         u64 num_bytes;
 604         int ret;
 605
 606         src_rsv = trans->block_rsv;
 607         dst_rsv = &fs_info->delayed_block_rsv;
 608
 609         num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 610
 611         /*
 612          * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 613          * which doesn't reserve space for speed.  This is a problem since we
 614          * still need to reserve space for this update, so try to reserve the
 615          * space.
 616          *
 617          * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
 618          * we always reserve enough to update the inode item.
 619          */
 620         if (!src_rsv || (!trans->bytes_reserved &&
 621                          src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
 622                 ret = btrfs_qgroup_reserve_meta_prealloc(root,
 623                                 fs_info->nodesize, true);
 624                 if (ret < 0)
 625                         return ret;
 626                 ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 627                                           BTRFS_RESERVE_NO_FLUSH);
 628                 /*
 629                  * Since we're under a transaction reserve_metadata_bytes could
 630                  * try to commit the transaction which will make it return
 631                  * EAGAIN to make us stop the transaction we have, so return
 632                  * ENOSPC instead so that btrfs_dirty_inode knows what to do.
 633                  */
 634                 if (ret == -EAGAIN) {
 635                         ret = -ENOSPC;
 636                         btrfs_qgroup_free_meta_prealloc(root, num_bytes);
 637                 }
 638                 if (!ret) {
 639                         node->bytes_reserved = num_bytes;
 640                         trace_btrfs_space_reservation(fs_info,
 641                                                       "delayed_inode",
 642                                                       btrfs_ino(inode),
 643                                                       num_bytes, 1);
 644                 } else {
 645                         btrfs_qgroup_free_meta_prealloc(root, fs_info->nodesize);
 646                 }
 647                 return ret;
 648         }
 649
 650         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 651         if (!ret) {
 652                 trace_btrfs_space_reservation(fs_info, "delayed_inode",
 653                                               btrfs_ino(inode), num_bytes, 1);
 654                 node->bytes_reserved = num_bytes;
 655         }
 656
 657         return ret;
 658 }
 659
 660 static void btrfs_delayed_inode_release_metadata(struct btrfs_fs_info *fs_info,
 661                                                 struct btrfs_delayed_node *node,
 662                                                 bool qgroup_free)
 663 {
 664         struct btrfs_block_rsv *rsv;
 665
 666         if (!node->bytes_reserved)
 667                 return;
 668
 669         rsv = &fs_info->delayed_block_rsv;
 670         trace_btrfs_space_reservation(fs_info, "delayed_inode",
 671                                       node->inode_id, node->bytes_reserved, 0);
 672         btrfs_block_rsv_release(fs_info, rsv,
 673                                 node->bytes_reserved);
 674         if (qgroup_free)
 675                 btrfs_qgroup_free_meta_prealloc(node->root,
 676                                 node->bytes_reserved);
 677         else
 678                 btrfs_qgroup_convert_reserved_meta(node->root,
 679                                 node->bytes_reserved);
 680         node->bytes_reserved = 0;
 681 }
 682
 683 /*
 684  * This helper will insert some continuous items into the same leaf according
 685  * to the free space of the leaf.
 686  */
 687 static int btrfs_batch_insert_items(struct btrfs_root *root,
 688                                     struct btrfs_path *path,
 689                                     struct btrfs_delayed_item *item)
 690 {
 691         struct btrfs_fs_info *fs_info = root->fs_info;
 692         struct btrfs_delayed_item *curr, *next;
 693         int free_space;
 694         int total_data_size = 0, total_size = 0;
 695         struct extent_buffer *leaf;
 696         char *data_ptr;
 697         struct btrfs_key *keys;
 698         u32 *data_size;
 699         struct list_head head;
 700         int slot;
 701         int nitems;
 702         int i;
 703         int ret = 0;
 704
 705         BUG_ON(!path->nodes[0]);
 706
 707         leaf = path->nodes[0];
 708         free_space = btrfs_leaf_free_space(fs_info, leaf);
 709         INIT_LIST_HEAD(&head);
 710
 711         next = item;
 712         nitems = 0;
 713
 714         /*
 715          * count the number of the continuous items that we can insert in batch
 716          */
 717         while (total_size + next->data_len + sizeof(struct btrfs_item) <=
 718                free_space) {
 719                 total_data_size += next->data_len;
 720                 total_size += next->data_len + sizeof(struct btrfs_item);
 721                 list_add_tail(&next->tree_list, &head);
 722                 nitems++;
 723
 724                 curr = next;
 725                 next = __btrfs_next_delayed_item(curr);
 726                 if (!next)
 727                         break;
 728
 729                 if (!btrfs_is_continuous_delayed_item(curr, next))
 730                         break;
 731         }
 732
 733         if (!nitems) {
 734                 ret = 0;
 735                 goto out;
 736         }
 737
 738         /*
 739          * we need allocate some memory space, but it might cause the task
 740          * to sleep, so we set all locked nodes in the path to blocking locks
 741          * first.
 742          */
 743         btrfs_set_path_blocking(path);
 744
 745         keys = kmalloc_array(nitems, sizeof(struct btrfs_key), GFP_NOFS);
 746         if (!keys) {
 747                 ret = -ENOMEM;
 748                 goto out;
 749         }
 750
 751         data_size = kmalloc_array(nitems, sizeof(u32), GFP_NOFS);
 752         if (!data_size) {
 753                 ret = -ENOMEM;
 754                 goto error;
 755         }
 756
 757         /* get keys of all the delayed items */
 758         i = 0;
 759         list_for_each_entry(next, &head, tree_list) {
 760                 keys[i] = next->key;
 761                 data_size[i] = next->data_len;
 762                 i++;
 763         }
 764
 765         /* reset all the locked nodes in the patch to spinning locks. */
 766         btrfs_clear_path_blocking(path, NULL, 0);
 767
 768         /* insert the keys of the items */
 769         setup_items_for_insert(root, path, keys, data_size,
 770                                total_data_size, total_size, nitems);
 771
 772         /* insert the dir index items */
 773         slot = path->slots[0];
 774         list_for_each_entry_safe(curr, next, &head, tree_list) {
 775                 data_ptr = btrfs_item_ptr(leaf, slot, char);
 776                 write_extent_buffer(leaf, &curr->data,
 777                                     (unsigned long)data_ptr,
 778                                     curr->data_len);
 779                 slot++;
 780
 781                 btrfs_delayed_item_release_metadata(root, curr);
 782
 783                 list_del(&curr->tree_list);
 784                 btrfs_release_delayed_item(curr);
 785         }
 786
 787 error:
 788         kfree(data_size);
 789         kfree(keys);
 790 out:
 791         return ret;
 792 }
 793
 794 /*
 795  * This helper can just do simple insertion that needn't extend item for new
 796  * data, such as directory name index insertion, inode insertion.
 797  */
 798 static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 799                                      struct btrfs_root *root,
 800                                      struct btrfs_path *path,
 801                                      struct btrfs_delayed_item *delayed_item)
 802 {
 803         struct extent_buffer *leaf;
 804         char *ptr;
 805         int ret;
 806
 807         ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
 808                                       delayed_item->data_len);
 809         if (ret < 0 && ret != -EEXIST)
 810                 return ret;
 811
 812         leaf = path->nodes[0];
 813
 814         ptr = btrfs_item_ptr(leaf, path->slots[0], char);
 815
 816         write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
 817                             delayed_item->data_len);
 818         btrfs_mark_buffer_dirty(leaf);
 819
 820         btrfs_delayed_item_release_metadata(root, delayed_item);
 821         return 0;
 822 }
 823
 824 /*
 825  * we insert an item first, then if there are some continuous items, we try
 826  * to insert those items into the same leaf.
 827  */
 828 static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 829                                       struct btrfs_path *path,
 830                                       struct btrfs_root *root,
 831                                       struct btrfs_delayed_node *node)
 832 {
 833         struct btrfs_delayed_item *curr, *prev;
 834         int ret = 0;
 835
 836 do_again:
 837         mutex_lock(&node->mutex);
 838         curr = __btrfs_first_delayed_insertion_item(node);
 839         if (!curr)
 840                 goto insert_end;
 841
 842         ret = btrfs_insert_delayed_item(trans, root, path, curr);
 843         if (ret < 0) {
 844                 btrfs_release_path(path);
 845                 goto insert_end;
 846         }
 847
 848         prev = curr;
 849         curr = __btrfs_next_delayed_item(prev);
 850         if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
 851                 /* insert the continuous items into the same leaf */
 852                 path->slots[0]++;
 853                 btrfs_batch_insert_items(root, path, curr);
 854         }
 855         btrfs_release_delayed_item(prev);
 856         btrfs_mark_buffer_dirty(path->nodes[0]);
 857
 858         btrfs_release_path(path);
 859         mutex_unlock(&node->mutex);
 860         goto do_again;
 861
 862 insert_end:
 863         mutex_unlock(&node->mutex);
 864         return ret;
 865 }
 866
 867 static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
 868                                     struct btrfs_root *root,
 869                                     struct btrfs_path *path,
 870                                     struct btrfs_delayed_item *item)
 871 {
 872         struct btrfs_delayed_item *curr, *next;
 873         struct extent_buffer *leaf;
 874         struct btrfs_key key;
 875         struct list_head head;
 876         int nitems, i, last_item;
 877         int ret = 0;
 878
 879         BUG_ON(!path->nodes[0]);
 880
 881         leaf = path->nodes[0];
 882
 883         i = path->slots[0];
 884         last_item = btrfs_header_nritems(leaf) - 1;
 885         if (i > last_item)
 886                 return -ENOENT; /* FIXME: Is errno suitable? */
 887
 888         next = item;
 889         INIT_LIST_HEAD(&head);
 890         btrfs_item_key_to_cpu(leaf, &key, i);
 891         nitems = 0;
 892         /*
 893          * count the number of the dir index items that we can delete in batch
 894          */
 895         while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
 896                 list_add_tail(&next->tree_list, &head);
 897                 nitems++;
 898
 899                 curr = next;
 900                 next = __btrfs_next_delayed_item(curr);
 901                 if (!next)
 902                         break;
 903
 904                 if (!btrfs_is_continuous_delayed_item(curr, next))
 905                         break;
 906
 907                 i++;
 908                 if (i > last_item)
 909                         break;
 910                 btrfs_item_key_to_cpu(leaf, &key, i);
 911         }
 912
 913         if (!nitems)
 914                 return 0;
 915
 916         ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 917         if (ret)
 918                 goto out;
 919
 920         list_for_each_entry_safe(curr, next, &head, tree_list) {
 921                 btrfs_delayed_item_release_metadata(root, curr);
 922                 list_del(&curr->tree_list);
 923                 btrfs_release_delayed_item(curr);
 924         }
 925
 926 out:
 927         return ret;
 928 }
 929
 930 static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 931                                       struct btrfs_path *path,
 932                                       struct btrfs_root *root,
 933                                       struct btrfs_delayed_node *node)
 934 {
 935         struct btrfs_delayed_item *curr, *prev;
 936         int ret = 0;
 937
 938 do_again:
 939         mutex_lock(&node->mutex);
 940         curr = __btrfs_first_delayed_deletion_item(node);
 941         if (!curr)
 942                 goto delete_fail;
 943
 944         ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
 945         if (ret < 0)
 946                 goto delete_fail;
 947         else if (ret > 0) {
 948                 /*
 949                  * can't find the item which the node points to, so this node
 950                  * is invalid, just drop it.
 951                  */
 952                 prev = curr;
 953                 curr = __btrfs_next_delayed_item(prev);
 954                 btrfs_release_delayed_item(prev);
 955                 ret = 0;
 956                 btrfs_release_path(path);
 957                 if (curr) {
 958                         mutex_unlock(&node->mutex);
 959                         goto do_again;
 960                 } else
 961                         goto delete_fail;
 962         }
 963
 964         btrfs_batch_delete_items(trans, root, path, curr);
 965         btrfs_release_path(path);
 966         mutex_unlock(&node->mutex);
 967         goto do_again;
 968
 969 delete_fail:
 970         btrfs_release_path(path);
 971         mutex_unlock(&node->mutex);
 972         return ret;
 973 }
 974
 975 static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
 976 {
 977         struct btrfs_delayed_root *delayed_root;
 978
 979         if (delayed_node &&
 980             test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
 981                 BUG_ON(!delayed_node->root);
 982                 clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
 983                 delayed_node->count--;
 984
 985                 delayed_root = delayed_node->root->fs_info->delayed_root;
 986                 finish_one_item(delayed_root);
 987         }
 988 }
 989
 990 static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
 991 {
 992         struct btrfs_delayed_root *delayed_root;
 993
 994         ASSERT(delayed_node->root);
 995         clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
 996         delayed_node->count--;
 997
 998         delayed_root = delayed_node->root->fs_info->delayed_root;
 999         finish_one_item(delayed_root);
1000 }
1001
1002 static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1003                                         struct btrfs_root *root,
1004                                         struct btrfs_path *path,
1005                                         struct btrfs_delayed_node *node)
1006 {
1007         struct btrfs_fs_info *fs_info = root->fs_info;
1008         struct btrfs_key key;
1009         struct btrfs_inode_item *inode_item;
1010         struct extent_buffer *leaf;
1011         int mod;
1012         int ret;
1013
1014         key.objectid = node->inode_id;
1015         key.type = BTRFS_INODE_ITEM_KEY;
1016         key.offset = 0;
1017
1018         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1019                 mod = -1;
1020         else
1021                 mod = 1;
1022
1023         ret = btrfs_lookup_inode(trans, root, path, &key, mod);
1024         if (ret > 0) {
1025                 btrfs_release_path(path);
1026                 return -ENOENT;
1027         } else if (ret < 0) {
1028                 return ret;
1029         }
1030
1031         leaf = path->nodes[0];
1032         inode_item = btrfs_item_ptr(leaf, path->slots[0],
1033                                     struct btrfs_inode_item);
1034         write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1035                             sizeof(struct btrfs_inode_item));
1036         btrfs_mark_buffer_dirty(leaf);
1037
1038         if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1039                 goto no_iref;
1040
1041         path->slots[0]++;
1042         if (path->slots[0] >= btrfs_header_nritems(leaf))
1043                 goto search;
1044 again:
1045         btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1046         if (key.objectid != node->inode_id)
1047                 goto out;
1048
1049         if (key.type != BTRFS_INODE_REF_KEY &&
1050             key.type != BTRFS_INODE_EXTREF_KEY)
1051                 goto out;
1052
1053         /*
1054          * Delayed iref deletion is for the inode who has only one link,
1055          * so there is only one iref. The case that several irefs are
1056          * in the same item doesn't exist.
1057          */
1058         btrfs_del_item(trans, root, path);
1059 out:
1060         btrfs_release_delayed_iref(node);
1061 no_iref:
1062         btrfs_release_path(path);
1063 err_out:
1064         btrfs_delayed_inode_release_metadata(fs_info, node, (ret < 0));
1065         btrfs_release_delayed_inode(node);
1066
1067         return ret;
1068
1069 search:
1070         btrfs_release_path(path);
1071
1072         key.type = BTRFS_INODE_EXTREF_KEY;
1073         key.offset = -1;
1074         ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1075         if (ret < 0)
1076                 goto err_out;
1077         ASSERT(ret);
1078
1079         ret = 0;
1080         leaf = path->nodes[0];
1081         path->slots[0]--;
1082         goto again;
1083 }
1084
1085 static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1086                                              struct btrfs_root *root,
1087                                              struct btrfs_path *path,
1088                                              struct btrfs_delayed_node *node)
1089 {
1090         int ret;
1091
1092         mutex_lock(&node->mutex);
1093         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
1094                 mutex_unlock(&node->mutex);
1095                 return 0;
1096         }
1097
1098         ret = __btrfs_update_delayed_inode(trans, root, path, node);
1099         mutex_unlock(&node->mutex);
1100         return ret;
1101 }
1102
1103 static inline int
1104 __btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1105                                    struct btrfs_path *path,
1106                                    struct btrfs_delayed_node *node)
1107 {
1108         int ret;
1109
1110         ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1111         if (ret)
1112                 return ret;
1113
1114         ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1115         if (ret)
1116                 return ret;
1117
1118         ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1119         return ret;
1120 }
1121
1122 /*
1123  * Called when committing the transaction.
1124  * Returns 0 on success.
1125  * Returns < 0 on error and returns with an aborted transaction with any
1126  * outstanding delayed items cleaned up.
1127  */
1128 static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans, int nr)
1129 {
1130         struct btrfs_fs_info *fs_info = trans->fs_info;
1131         struct btrfs_delayed_root *delayed_root;
1132         struct btrfs_delayed_node *curr_node, *prev_node;
1133         struct btrfs_path *path;
1134         struct btrfs_block_rsv *block_rsv;
1135         int ret = 0;
1136         bool count = (nr > 0);
1137
1138         if (trans->aborted)
1139                 return -EIO;
1140
1141         path = btrfs_alloc_path();
1142         if (!path)
1143                 return -ENOMEM;
1144         path->leave_spinning = 1;
1145
1146         block_rsv = trans->block_rsv;
1147         trans->block_rsv = &fs_info->delayed_block_rsv;
1148
1149         delayed_root = fs_info->delayed_root;
1150
1151         curr_node = btrfs_first_delayed_node(delayed_root);
1152         while (curr_node && (!count || (count && nr--))) {
1153                 ret = __btrfs_commit_inode_delayed_items(trans, path,
1154                                                          curr_node);
1155                 if (ret) {
1156                         btrfs_release_delayed_node(curr_node);
1157                         curr_node = NULL;
1158                         btrfs_abort_transaction(trans, ret);
1159                         break;
1160                 }
1161
1162                 prev_node = curr_node;
1163                 curr_node = btrfs_next_delayed_node(curr_node);
1164                 btrfs_release_delayed_node(prev_node);
1165         }
1166
1167         if (curr_node)
1168                 btrfs_release_delayed_node(curr_node);
1169         btrfs_free_path(path);
1170         trans->block_rsv = block_rsv;
1171
1172         return ret;
1173 }
1174
1175 int btrfs_run_delayed_items(struct btrfs_trans_handle *trans)
1176 {
1177         return __btrfs_run_delayed_items(trans, -1);
1178 }
1179
1180 int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans, int nr)
1181 {
1182         return __btrfs_run_delayed_items(trans, nr);
1183 }
1184
1185 int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1186                                      struct btrfs_inode *inode)
1187 {
1188         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1189         struct btrfs_path *path;
1190         struct btrfs_block_rsv *block_rsv;
1191         int ret;
1192
1193         if (!delayed_node)
1194                 return 0;
1195
1196         mutex_lock(&delayed_node->mutex);
1197         if (!delayed_node->count) {
1198                 mutex_unlock(&delayed_node->mutex);
1199                 btrfs_release_delayed_node(delayed_node);
1200                 return 0;
1201         }
1202         mutex_unlock(&delayed_node->mutex);
1203
1204         path = btrfs_alloc_path();
1205         if (!path) {
1206                 btrfs_release_delayed_node(delayed_node);
1207                 return -ENOMEM;
1208         }
1209         path->leave_spinning = 1;
1210
1211         block_rsv = trans->block_rsv;
1212         trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1213
1214         ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1215
1216         btrfs_release_delayed_node(delayed_node);
1217         btrfs_free_path(path);
1218         trans->block_rsv = block_rsv;
1219
1220         return ret;
1221 }
1222
1223 int btrfs_commit_inode_delayed_inode(struct btrfs_inode *inode)
1224 {
1225         struct btrfs_fs_info *fs_info = inode->root->fs_info;
1226         struct btrfs_trans_handle *trans;
1227         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1228         struct btrfs_path *path;
1229         struct btrfs_block_rsv *block_rsv;
1230         int ret;
1231
1232         if (!delayed_node)
1233                 return 0;
1234
1235         mutex_lock(&delayed_node->mutex);
1236         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1237                 mutex_unlock(&delayed_node->mutex);
1238                 btrfs_release_delayed_node(delayed_node);
1239                 return 0;
1240         }
1241         mutex_unlock(&delayed_node->mutex);
1242
1243         trans = btrfs_join_transaction(delayed_node->root);
1244         if (IS_ERR(trans)) {
1245                 ret = PTR_ERR(trans);
1246                 goto out;
1247         }
1248
1249         path = btrfs_alloc_path();
1250         if (!path) {
1251                 ret = -ENOMEM;
1252                 goto trans_out;
1253         }
1254         path->leave_spinning = 1;
1255
1256         block_rsv = trans->block_rsv;
1257         trans->block_rsv = &fs_info->delayed_block_rsv;
1258
1259         mutex_lock(&delayed_node->mutex);
1260         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
1261                 ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1262                                                    path, delayed_node);
1263         else
1264                 ret = 0;
1265         mutex_unlock(&delayed_node->mutex);
1266
1267         btrfs_free_path(path);
1268         trans->block_rsv = block_rsv;
1269 trans_out:
1270         btrfs_end_transaction(trans);
1271         btrfs_btree_balance_dirty(fs_info);
1272 out:
1273         btrfs_release_delayed_node(delayed_node);
1274
1275         return ret;
1276 }
1277
1278 void btrfs_remove_delayed_node(struct btrfs_inode *inode)
1279 {
1280         struct btrfs_delayed_node *delayed_node;
1281
1282         delayed_node = READ_ONCE(inode->delayed_node);
1283         if (!delayed_node)
1284                 return;
1285
1286         inode->delayed_node = NULL;
1287         btrfs_release_delayed_node(delayed_node);
1288 }
1289
1290 struct btrfs_async_delayed_work {
1291         struct btrfs_delayed_root *delayed_root;
1292         int nr;
1293         struct btrfs_work work;
1294 };
1295
1296 static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1297 {
1298         struct btrfs_async_delayed_work *async_work;
1299         struct btrfs_delayed_root *delayed_root;
1300         struct btrfs_trans_handle *trans;
1301         struct btrfs_path *path;
1302         struct btrfs_delayed_node *delayed_node = NULL;
1303         struct btrfs_root *root;
1304         struct btrfs_block_rsv *block_rsv;
1305         int total_done = 0;
1306
1307         async_work = container_of(work, struct btrfs_async_delayed_work, work);
1308         delayed_root = async_work->delayed_root;
1309
1310         path = btrfs_alloc_path();
1311         if (!path)
1312                 goto out;
1313
1314         do {
1315                 if (atomic_read(&delayed_root->items) <
1316                     BTRFS_DELAYED_BACKGROUND / 2)
1317                         break;
1318
1319                 delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1320                 if (!delayed_node)
1321                         break;
1322
1323                 path->leave_spinning = 1;
1324                 root = delayed_node->root;
1325
1326                 trans = btrfs_join_transaction(root);
1327                 if (IS_ERR(trans)) {
1328                         btrfs_release_path(path);
1329                         btrfs_release_prepared_delayed_node(delayed_node);
1330                         total_done++;
1331                         continue;
1332                 }
1333
1334                 block_rsv = trans->block_rsv;
1335                 trans->block_rsv = &root->fs_info->delayed_block_rsv;
1336
1337                 __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1338
1339                 trans->block_rsv = block_rsv;
1340                 btrfs_end_transaction(trans);
1341                 btrfs_btree_balance_dirty_nodelay(root->fs_info);
1342
1343                 btrfs_release_path(path);
1344                 btrfs_release_prepared_delayed_node(delayed_node);
1345                 total_done++;
1346
1347         } while ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK)
1348                  || total_done < async_work->nr);
1349
1350         btrfs_free_path(path);
1351 out:
1352         wake_up(&delayed_root->wait);
1353         kfree(async_work);
1354 }
1355
1356
1357 static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1358                                      struct btrfs_fs_info *fs_info, int nr)
1359 {
1360         struct btrfs_async_delayed_work *async_work;
1361
1362         async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
1363         if (!async_work)
1364                 return -ENOMEM;
1365
1366         async_work->delayed_root = delayed_root;
1367         btrfs_init_work(&async_work->work, btrfs_delayed_meta_helper,
1368                         btrfs_async_run_delayed_root, NULL, NULL);
1369         async_work->nr = nr;
1370
1371         btrfs_queue_work(fs_info->delayed_workers, &async_work->work);
1372         return 0;
1373 }
1374
1375 void btrfs_assert_delayed_root_empty(struct btrfs_fs_info *fs_info)
1376 {
1377         WARN_ON(btrfs_first_delayed_node(fs_info->delayed_root));
1378 }
1379
1380 static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
1381 {
1382         int val = atomic_read(&delayed_root->items_seq);
1383
1384         if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
1385                 return 1;
1386
1387         if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1388                 return 1;
1389
1390         return 0;
1391 }
1392
1393 void btrfs_balance_delayed_items(struct btrfs_fs_info *fs_info)
1394 {
1395         struct btrfs_delayed_root *delayed_root = fs_info->delayed_root;
1396
1397         if ((atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND) ||
1398                 btrfs_workqueue_normal_congested(fs_info->delayed_workers))
1399                 return;
1400
1401         if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1402                 int seq;
1403                 int ret;
1404
1405                 seq = atomic_read(&delayed_root->items_seq);
1406
1407                 ret = btrfs_wq_run_delayed_node(delayed_root, fs_info, 0);
1408                 if (ret)
1409                         return;
1410
1411                 wait_event_interruptible(delayed_root->wait,
1412                                          could_end_wait(delayed_root, seq));
1413                 return;
1414         }
1415
1416         btrfs_wq_run_delayed_node(delayed_root, fs_info, BTRFS_DELAYED_BATCH);
1417 }
1418
1419 /* Will return 0 or -ENOMEM */
1420 int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1421                                    struct btrfs_fs_info *fs_info,
1422                                    const char *name, int name_len,
1423                                    struct btrfs_inode *dir,
1424                                    struct btrfs_disk_key *disk_key, u8 type,
1425                                    u64 index)
1426 {
1427         struct btrfs_delayed_node *delayed_node;
1428         struct btrfs_delayed_item *delayed_item;
1429         struct btrfs_dir_item *dir_item;
1430         int ret;
1431
1432         delayed_node = btrfs_get_or_create_delayed_node(dir);
1433         if (IS_ERR(delayed_node))
1434                 return PTR_ERR(delayed_node);
1435
1436         delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
1437         if (!delayed_item) {
1438                 ret = -ENOMEM;
1439                 goto release_node;
1440         }
1441
1442         delayed_item->key.objectid = btrfs_ino(dir);
1443         delayed_item->key.type = BTRFS_DIR_INDEX_KEY;
1444         delayed_item->key.offset = index;
1445
1446         dir_item = (struct btrfs_dir_item *)delayed_item->data;
1447         dir_item->location = *disk_key;
1448         btrfs_set_stack_dir_transid(dir_item, trans->transid);
1449         btrfs_set_stack_dir_data_len(dir_item, 0);
1450         btrfs_set_stack_dir_name_len(dir_item, name_len);
1451         btrfs_set_stack_dir_type(dir_item, type);
1452         memcpy((char *)(dir_item + 1), name, name_len);
1453
1454         ret = btrfs_delayed_item_reserve_metadata(trans, dir->root, delayed_item);
1455         /*
1456          * we have reserved enough space when we start a new transaction,
1457          * so reserving metadata failure is impossible
1458          */
1459         BUG_ON(ret);
1460
1461
1462         mutex_lock(&delayed_node->mutex);
1463         ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1464         if (unlikely(ret)) {
1465                 btrfs_err(fs_info,
1466                           "err add delayed dir index item(name: %.*s) into the insertion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1467                           name_len, name, delayed_node->root->objectid,
1468                           delayed_node->inode_id, ret);
1469                 BUG();
1470         }
1471         mutex_unlock(&delayed_node->mutex);
1472
1473 release_node:
1474         btrfs_release_delayed_node(delayed_node);
1475         return ret;
1476 }
1477
1478 static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info,
1479                                                struct btrfs_delayed_node *node,
1480                                                struct btrfs_key *key)
1481 {
1482         struct btrfs_delayed_item *item;
1483
1484         mutex_lock(&node->mutex);
1485         item = __btrfs_lookup_delayed_insertion_item(node, key);
1486         if (!item) {
1487                 mutex_unlock(&node->mutex);
1488                 return 1;
1489         }
1490
1491         btrfs_delayed_item_release_metadata(node->root, item);
1492         btrfs_release_delayed_item(item);
1493         mutex_unlock(&node->mutex);
1494         return 0;
1495 }
1496
1497 int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1498                                    struct btrfs_fs_info *fs_info,
1499                                    struct btrfs_inode *dir, u64 index)
1500 {
1501         struct btrfs_delayed_node *node;
1502         struct btrfs_delayed_item *item;
1503         struct btrfs_key item_key;
1504         int ret;
1505
1506         node = btrfs_get_or_create_delayed_node(dir);
1507         if (IS_ERR(node))
1508                 return PTR_ERR(node);
1509
1510         item_key.objectid = btrfs_ino(dir);
1511         item_key.type = BTRFS_DIR_INDEX_KEY;
1512         item_key.offset = index;
1513
1514         ret = btrfs_delete_delayed_insertion_item(fs_info, node, &item_key);
1515         if (!ret)
1516                 goto end;
1517
1518         item = btrfs_alloc_delayed_item(0);
1519         if (!item) {
1520                 ret = -ENOMEM;
1521                 goto end;
1522         }
1523
1524         item->key = item_key;
1525
1526         ret = btrfs_delayed_item_reserve_metadata(trans, dir->root, item);
1527         /*
1528          * we have reserved enough space when we start a new transaction,
1529          * so reserving metadata failure is impossible.
1530          */
1531         BUG_ON(ret);
1532
1533         mutex_lock(&node->mutex);
1534         ret = __btrfs_add_delayed_deletion_item(node, item);
1535         if (unlikely(ret)) {
1536                 btrfs_err(fs_info,
1537                           "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1538                           index, node->root->objectid, node->inode_id, ret);
1539                 BUG();
1540         }
1541         mutex_unlock(&node->mutex);
1542 end:
1543         btrfs_release_delayed_node(node);
1544         return ret;
1545 }
1546
1547 int btrfs_inode_delayed_dir_index_count(struct btrfs_inode *inode)
1548 {
1549         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1550
1551         if (!delayed_node)
1552                 return -ENOENT;
1553
1554         /*
1555          * Since we have held i_mutex of this directory, it is impossible that
1556          * a new directory index is added into the delayed node and index_cnt
1557          * is updated now. So we needn't lock the delayed node.
1558          */
1559         if (!delayed_node->index_cnt) {
1560                 btrfs_release_delayed_node(delayed_node);
1561                 return -EINVAL;
1562         }
1563
1564         inode->index_cnt = delayed_node->index_cnt;
1565         btrfs_release_delayed_node(delayed_node);
1566         return 0;
1567 }
1568
1569 bool btrfs_readdir_get_delayed_items(struct inode *inode,
1570                                      struct list_head *ins_list,
1571                                      struct list_head *del_list)
1572 {
1573         struct btrfs_delayed_node *delayed_node;
1574         struct btrfs_delayed_item *item;
1575
1576         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1577         if (!delayed_node)
1578                 return false;
1579
1580         /*
1581          * We can only do one readdir with delayed items at a time because of
1582          * item->readdir_list.
1583          */
1584         inode_unlock_shared(inode);
1585         inode_lock(inode);
1586
1587         mutex_lock(&delayed_node->mutex);
1588         item = __btrfs_first_delayed_insertion_item(delayed_node);
1589         while (item) {
1590                 refcount_inc(&item->refs);
1591                 list_add_tail(&item->readdir_list, ins_list);
1592                 item = __btrfs_next_delayed_item(item);
1593         }
1594
1595         item = __btrfs_first_delayed_deletion_item(delayed_node);
1596         while (item) {
1597                 refcount_inc(&item->refs);
1598                 list_add_tail(&item->readdir_list, del_list);
1599                 item = __btrfs_next_delayed_item(item);
1600         }
1601         mutex_unlock(&delayed_node->mutex);
1602         /*
1603          * This delayed node is still cached in the btrfs inode, so refs
1604          * must be > 1 now, and we needn't check it is going to be freed
1605          * or not.
1606          *
1607          * Besides that, this function is used to read dir, we do not
1608          * insert/delete delayed items in this period. So we also needn't
1609          * requeue or dequeue this delayed node.
1610          */
1611         refcount_dec(&delayed_node->refs);
1612
1613         return true;
1614 }
1615
1616 void btrfs_readdir_put_delayed_items(struct inode *inode,
1617                                      struct list_head *ins_list,
1618                                      struct list_head *del_list)
1619 {
1620         struct btrfs_delayed_item *curr, *next;
1621
1622         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1623                 list_del(&curr->readdir_list);
1624                 if (refcount_dec_and_test(&curr->refs))
1625                         kfree(curr);
1626         }
1627
1628         list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1629                 list_del(&curr->readdir_list);
1630                 if (refcount_dec_and_test(&curr->refs))
1631                         kfree(curr);
1632         }
1633
1634         /*
1635          * The VFS is going to do up_read(), so we need to downgrade back to a
1636          * read lock.
1637          */
1638         downgrade_write(&inode->i_rwsem);
1639 }
1640
1641 int btrfs_should_delete_dir_index(struct list_head *del_list,
1642                                   u64 index)
1643 {
1644         struct btrfs_delayed_item *curr;
1645         int ret = 0;
1646
1647         list_for_each_entry(curr, del_list, readdir_list) {
1648                 if (curr->key.offset > index)
1649                         break;
1650                 if (curr->key.offset == index) {
1651                         ret = 1;
1652                         break;
1653                 }
1654         }
1655         return ret;
1656 }
1657
1658 /*
1659  * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1660  *
1661  */
1662 int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
1663                                     struct list_head *ins_list)
1664 {
1665         struct btrfs_dir_item *di;
1666         struct btrfs_delayed_item *curr, *next;
1667         struct btrfs_key location;
1668         char *name;
1669         int name_len;
1670         int over = 0;
1671         unsigned char d_type;
1672
1673         if (list_empty(ins_list))
1674                 return 0;
1675
1676         /*
1677          * Changing the data of the delayed item is impossible. So
1678          * we needn't lock them. And we have held i_mutex of the
1679          * directory, nobody can delete any directory indexes now.
1680          */
1681         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1682                 list_del(&curr->readdir_list);
1683
1684                 if (curr->key.offset < ctx->pos) {
1685                         if (refcount_dec_and_test(&curr->refs))
1686                                 kfree(curr);
1687                         continue;
1688                 }
1689
1690                 ctx->pos = curr->key.offset;
1691
1692                 di = (struct btrfs_dir_item *)curr->data;
1693                 name = (char *)(di + 1);
1694                 name_len = btrfs_stack_dir_name_len(di);
1695
1696                 d_type = btrfs_filetype_table[di->type];
1697                 btrfs_disk_key_to_cpu(&location, &di->location);
1698
1699                 over = !dir_emit(ctx, name, name_len,
1700                                location.objectid, d_type);
1701
1702                 if (refcount_dec_and_test(&curr->refs))
1703                         kfree(curr);
1704
1705                 if (over)
1706                         return 1;
1707                 ctx->pos++;
1708         }
1709         return 0;
1710 }
1711
1712 static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1713                                   struct btrfs_inode_item *inode_item,
1714                                   struct inode *inode)
1715 {
1716         btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1717         btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1718         btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1719         btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1720         btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1721         btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1722         btrfs_set_stack_inode_generation(inode_item,
1723                                          BTRFS_I(inode)->generation);
1724         btrfs_set_stack_inode_sequence(inode_item,
1725                                        inode_peek_iversion(inode));
1726         btrfs_set_stack_inode_transid(inode_item, trans->transid);
1727         btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1728         btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
1729         btrfs_set_stack_inode_block_group(inode_item, 0);
1730
1731         btrfs_set_stack_timespec_sec(&inode_item->atime,
1732                                      inode->i_atime.tv_sec);
1733         btrfs_set_stack_timespec_nsec(&inode_item->atime,
1734                                       inode->i_atime.tv_nsec);
1735
1736         btrfs_set_stack_timespec_sec(&inode_item->mtime,
1737                                      inode->i_mtime.tv_sec);
1738         btrfs_set_stack_timespec_nsec(&inode_item->mtime,
1739                                       inode->i_mtime.tv_nsec);
1740
1741         btrfs_set_stack_timespec_sec(&inode_item->ctime,
1742                                      inode->i_ctime.tv_sec);
1743         btrfs_set_stack_timespec_nsec(&inode_item->ctime,
1744                                       inode->i_ctime.tv_nsec);
1745
1746         btrfs_set_stack_timespec_sec(&inode_item->otime,
1747                                      BTRFS_I(inode)->i_otime.tv_sec);
1748         btrfs_set_stack_timespec_nsec(&inode_item->otime,
1749                                      BTRFS_I(inode)->i_otime.tv_nsec);
1750 }
1751
1752 int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1753 {
1754         struct btrfs_delayed_node *delayed_node;
1755         struct btrfs_inode_item *inode_item;
1756
1757         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1758         if (!delayed_node)
1759                 return -ENOENT;
1760
1761         mutex_lock(&delayed_node->mutex);
1762         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1763                 mutex_unlock(&delayed_node->mutex);
1764                 btrfs_release_delayed_node(delayed_node);
1765                 return -ENOENT;
1766         }
1767
1768         inode_item = &delayed_node->inode_item;
1769
1770         i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1771         i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1772         btrfs_i_size_write(BTRFS_I(inode), btrfs_stack_inode_size(inode_item));
1773         inode->i_mode = btrfs_stack_inode_mode(inode_item);
1774         set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1775         inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1776         BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1777         BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
1778
1779         inode_set_iversion_queried(inode,
1780                                    btrfs_stack_inode_sequence(inode_item));
1781         inode->i_rdev = 0;
1782         *rdev = btrfs_stack_inode_rdev(inode_item);
1783         BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
1784
1785         inode->i_atime.tv_sec = btrfs_stack_timespec_sec(&inode_item->atime);
1786         inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->atime);
1787
1788         inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(&inode_item->mtime);
1789         inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->mtime);
1790
1791         inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(&inode_item->ctime);
1792         inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->ctime);
1793
1794         BTRFS_I(inode)->i_otime.tv_sec =
1795                 btrfs_stack_timespec_sec(&inode_item->otime);
1796         BTRFS_I(inode)->i_otime.tv_nsec =
1797                 btrfs_stack_timespec_nsec(&inode_item->otime);
1798
1799         inode->i_generation = BTRFS_I(inode)->generation;
1800         BTRFS_I(inode)->index_cnt = (u64)-1;
1801
1802         mutex_unlock(&delayed_node->mutex);
1803         btrfs_release_delayed_node(delayed_node);
1804         return 0;
1805 }
1806
1807 int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1808                                struct btrfs_root *root, struct inode *inode)
1809 {
1810         struct btrfs_delayed_node *delayed_node;
1811         int ret = 0;
1812
1813         delayed_node = btrfs_get_or_create_delayed_node(BTRFS_I(inode));
1814         if (IS_ERR(delayed_node))
1815                 return PTR_ERR(delayed_node);
1816
1817         mutex_lock(&delayed_node->mutex);
1818         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1819                 fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1820                 goto release_node;
1821         }
1822
1823         ret = btrfs_delayed_inode_reserve_metadata(trans, root, BTRFS_I(inode),
1824                                                    delayed_node);
1825         if (ret)
1826                 goto release_node;
1827
1828         fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1829         set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1830         delayed_node->count++;
1831         atomic_inc(&root->fs_info->delayed_root->items);
1832 release_node:
1833         mutex_unlock(&delayed_node->mutex);
1834         btrfs_release_delayed_node(delayed_node);
1835         return ret;
1836 }
1837
1838 int btrfs_delayed_delete_inode_ref(struct btrfs_inode *inode)
1839 {
1840         struct btrfs_fs_info *fs_info = inode->root->fs_info;
1841         struct btrfs_delayed_node *delayed_node;
1842
1843         /*
1844          * we don't do delayed inode updates during log recovery because it
1845          * leads to enospc problems.  This means we also can't do
1846          * delayed inode refs
1847          */
1848         if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
1849                 return -EAGAIN;
1850
1851         delayed_node = btrfs_get_or_create_delayed_node(inode);
1852         if (IS_ERR(delayed_node))
1853                 return PTR_ERR(delayed_node);
1854
1855         /*
1856          * We don't reserve space for inode ref deletion is because:
1857          * - We ONLY do async inode ref deletion for the inode who has only
1858          *   one link(i_nlink == 1), it means there is only one inode ref.
1859          *   And in most case, the inode ref and the inode item are in the
1860          *   same leaf, and we will deal with them at the same time.
1861          *   Since we are sure we will reserve the space for the inode item,
1862          *   it is unnecessary to reserve space for inode ref deletion.
1863          * - If the inode ref and the inode item are not in the same leaf,
1864          *   We also needn't worry about enospc problem, because we reserve
1865          *   much more space for the inode update than it needs.
1866          * - At the worst, we can steal some space from the global reservation.
1867          *   It is very rare.
1868          */
1869         mutex_lock(&delayed_node->mutex);
1870         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1871                 goto release_node;
1872
1873         set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1874         delayed_node->count++;
1875         atomic_inc(&fs_info->delayed_root->items);
1876 release_node:
1877         mutex_unlock(&delayed_node->mutex);
1878         btrfs_release_delayed_node(delayed_node);
1879         return 0;
1880 }
1881
1882 static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1883 {
1884         struct btrfs_root *root = delayed_node->root;
1885         struct btrfs_fs_info *fs_info = root->fs_info;
1886         struct btrfs_delayed_item *curr_item, *prev_item;
1887
1888         mutex_lock(&delayed_node->mutex);
1889         curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1890         while (curr_item) {
1891                 btrfs_delayed_item_release_metadata(root, curr_item);
1892                 prev_item = curr_item;
1893                 curr_item = __btrfs_next_delayed_item(prev_item);
1894                 btrfs_release_delayed_item(prev_item);
1895         }
1896
1897         curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1898         while (curr_item) {
1899                 btrfs_delayed_item_release_metadata(root, curr_item);
1900                 prev_item = curr_item;
1901                 curr_item = __btrfs_next_delayed_item(prev_item);
1902                 btrfs_release_delayed_item(prev_item);
1903         }
1904
1905         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1906                 btrfs_release_delayed_iref(delayed_node);
1907
1908         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1909                 btrfs_delayed_inode_release_metadata(fs_info, delayed_node, false);
1910                 btrfs_release_delayed_inode(delayed_node);
1911         }
1912         mutex_unlock(&delayed_node->mutex);
1913 }
1914
1915 void btrfs_kill_delayed_inode_items(struct btrfs_inode *inode)
1916 {
1917         struct btrfs_delayed_node *delayed_node;
1918
1919         delayed_node = btrfs_get_delayed_node(inode);
1920         if (!delayed_node)
1921                 return;
1922
1923         __btrfs_kill_delayed_node(delayed_node);
1924         btrfs_release_delayed_node(delayed_node);
1925 }
1926
1927 void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1928 {
1929         u64 inode_id = 0;
1930         struct btrfs_delayed_node *delayed_nodes[8];
1931         int i, n;
1932
1933         while (1) {
1934                 spin_lock(&root->inode_lock);
1935                 n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1936                                            (void **)delayed_nodes, inode_id,
1937                                            ARRAY_SIZE(delayed_nodes));
1938                 if (!n) {
1939                         spin_unlock(&root->inode_lock);
1940                         break;
1941                 }
1942
1943                 inode_id = delayed_nodes[n - 1]->inode_id + 1;
1944
1945                 for (i = 0; i < n; i++)
1946                         refcount_inc(&delayed_nodes[i]->refs);
1947                 spin_unlock(&root->inode_lock);
1948
1949                 for (i = 0; i < n; i++) {
1950                         __btrfs_kill_delayed_node(delayed_nodes[i]);
1951                         btrfs_release_delayed_node(delayed_nodes[i]);
1952                 }
1953         }
1954 }
1955
1956 void btrfs_destroy_delayed_inodes(struct btrfs_fs_info *fs_info)
1957 {
1958         struct btrfs_delayed_node *curr_node, *prev_node;
1959
1960         curr_node = btrfs_first_delayed_node(fs_info->delayed_root);
1961         while (curr_node) {
1962                 __btrfs_kill_delayed_node(curr_node);
1963
1964                 prev_node = curr_node;
1965                 curr_node = btrfs_next_delayed_node(curr_node);
1966                 btrfs_release_delayed_node(prev_node);
1967         }
1968 }
1969