fs/btrfs/delayed-inode.c

   1 /*
   2  * Copyright (C) 2011 Fujitsu.  All rights reserved.
   3  * Written by Miao Xie <miaox@cn.fujitsu.com>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public
   7  * License v2 as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public
  15  * License along with this program; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 021110-1307, USA.
  18  */
  19
  20 #include <linux/slab.h>
  21 #include <linux/iversion.h>
  22 #include "delayed-inode.h"
  23 #include "disk-io.h"
  24 #include "transaction.h"
  25 #include "ctree.h"
  26
  27 #define BTRFS_DELAYED_WRITEBACK         512
  28 #define BTRFS_DELAYED_BACKGROUND        128
  29 #define BTRFS_DELAYED_BATCH             16
  30
  31 static struct kmem_cache *delayed_node_cache;
  32
  33 int __init btrfs_delayed_inode_init(void)
  34 {
  35         delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
  36                                         sizeof(struct btrfs_delayed_node),
  37                                         0,
  38                                         SLAB_MEM_SPREAD,
  39                                         NULL);
  40         if (!delayed_node_cache)
  41                 return -ENOMEM;
  42         return 0;
  43 }
  44
  45 void btrfs_delayed_inode_exit(void)
  46 {
  47         kmem_cache_destroy(delayed_node_cache);
  48 }
  49
  50 static inline void btrfs_init_delayed_node(
  51                                 struct btrfs_delayed_node *delayed_node,
  52                                 struct btrfs_root *root, u64 inode_id)
  53 {
  54         delayed_node->root = root;
  55         delayed_node->inode_id = inode_id;
  56         refcount_set(&delayed_node->refs, 0);
  57         delayed_node->ins_root = RB_ROOT;
  58         delayed_node->del_root = RB_ROOT;
  59         mutex_init(&delayed_node->mutex);
  60         INIT_LIST_HEAD(&delayed_node->n_list);
  61         INIT_LIST_HEAD(&delayed_node->p_list);
  62 }
  63
  64 static inline int btrfs_is_continuous_delayed_item(
  65                                         struct btrfs_delayed_item *item1,
  66                                         struct btrfs_delayed_item *item2)
  67 {
  68         if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
  69             item1->key.objectid == item2->key.objectid &&
  70             item1->key.type == item2->key.type &&
  71             item1->key.offset + 1 == item2->key.offset)
  72                 return 1;
  73         return 0;
  74 }
  75
  76 static struct btrfs_delayed_node *btrfs_get_delayed_node(
  77                 struct btrfs_inode *btrfs_inode)
  78 {
  79         struct btrfs_root *root = btrfs_inode->root;
  80         u64 ino = btrfs_ino(btrfs_inode);
  81         struct btrfs_delayed_node *node;
  82
  83         node = READ_ONCE(btrfs_inode->delayed_node);
  84         if (node) {
  85                 refcount_inc(&node->refs);
  86                 return node;
  87         }
  88
  89         spin_lock(&root->inode_lock);
  90         node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
  91
  92         if (node) {
  93                 if (btrfs_inode->delayed_node) {
  94                         refcount_inc(&node->refs);      /* can be accessed */
  95                         BUG_ON(btrfs_inode->delayed_node != node);
  96                         spin_unlock(&root->inode_lock);
  97                         return node;
  98                 }
  99
 100                 /*
 101                  * It's possible that we're racing into the middle of removing
 102                  * this node from the radix tree.  In this case, the refcount
 103                  * was zero and it should never go back to one.  Just return
 104                  * NULL like it was never in the radix at all; our release
 105                  * function is in the process of removing it.
 106                  *
 107                  * Some implementations of refcount_inc refuse to bump the
 108                  * refcount once it has hit zero.  If we don't do this dance
 109                  * here, refcount_inc() may decide to just WARN_ONCE() instead
 110                  * of actually bumping the refcount.
 111                  *
 112                  * If this node is properly in the radix, we want to bump the
 113                  * refcount twice, once for the inode and once for this get
 114                  * operation.
 115                  */
 116                 if (refcount_inc_not_zero(&node->refs)) {
 117                         refcount_inc(&node->refs);
 118                         btrfs_inode->delayed_node = node;
 119                 } else {
 120                         node = NULL;
 121                 }
 122
 123                 spin_unlock(&root->inode_lock);
 124                 return node;
 125         }
 126         spin_unlock(&root->inode_lock);
 127
 128         return NULL;
 129 }
 130
 131 /* Will return either the node or PTR_ERR(-ENOMEM) */
 132 static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 133                 struct btrfs_inode *btrfs_inode)
 134 {
 135         struct btrfs_delayed_node *node;
 136         struct btrfs_root *root = btrfs_inode->root;
 137         u64 ino = btrfs_ino(btrfs_inode);
 138         int ret;
 139
 140 again:
 141         node = btrfs_get_delayed_node(btrfs_inode);
 142         if (node)
 143                 return node;
 144
 145         node = kmem_cache_zalloc(delayed_node_cache, GFP_NOFS);
 146         if (!node)
 147                 return ERR_PTR(-ENOMEM);
 148         btrfs_init_delayed_node(node, root, ino);
 149
 150         /* cached in the btrfs inode and can be accessed */
 151         refcount_set(&node->refs, 2);
 152
 153         ret = radix_tree_preload(GFP_NOFS);
 154         if (ret) {
 155                 kmem_cache_free(delayed_node_cache, node);
 156                 return ERR_PTR(ret);
 157         }
 158
 159         spin_lock(&root->inode_lock);
 160         ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
 161         if (ret == -EEXIST) {
 162                 spin_unlock(&root->inode_lock);
 163                 kmem_cache_free(delayed_node_cache, node);
 164                 radix_tree_preload_end();
 165                 goto again;
 166         }
 167         btrfs_inode->delayed_node = node;
 168         spin_unlock(&root->inode_lock);
 169         radix_tree_preload_end();
 170
 171         return node;
 172 }
 173
 174 /*
 175  * Call it when holding delayed_node->mutex
 176  *
 177  * If mod = 1, add this node into the prepared list.
 178  */
 179 static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
 180                                      struct btrfs_delayed_node *node,
 181                                      int mod)
 182 {
 183         spin_lock(&root->lock);
 184         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 185                 if (!list_empty(&node->p_list))
 186                         list_move_tail(&node->p_list, &root->prepare_list);
 187                 else if (mod)
 188                         list_add_tail(&node->p_list, &root->prepare_list);
 189         } else {
 190                 list_add_tail(&node->n_list, &root->node_list);
 191                 list_add_tail(&node->p_list, &root->prepare_list);
 192                 refcount_inc(&node->refs);      /* inserted into list */
 193                 root->nodes++;
 194                 set_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 195         }
 196         spin_unlock(&root->lock);
 197 }
 198
 199 /* Call it when holding delayed_node->mutex */
 200 static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
 201                                        struct btrfs_delayed_node *node)
 202 {
 203         spin_lock(&root->lock);
 204         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 205                 root->nodes--;
 206                 refcount_dec(&node->refs);      /* not in the list */
 207                 list_del_init(&node->n_list);
 208                 if (!list_empty(&node->p_list))
 209                         list_del_init(&node->p_list);
 210                 clear_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 211         }
 212         spin_unlock(&root->lock);
 213 }
 214
 215 static struct btrfs_delayed_node *btrfs_first_delayed_node(
 216                         struct btrfs_delayed_root *delayed_root)
 217 {
 218         struct list_head *p;
 219         struct btrfs_delayed_node *node = NULL;
 220
 221         spin_lock(&delayed_root->lock);
 222         if (list_empty(&delayed_root->node_list))
 223                 goto out;
 224
 225         p = delayed_root->node_list.next;
 226         node = list_entry(p, struct btrfs_delayed_node, n_list);
 227         refcount_inc(&node->refs);
 228 out:
 229         spin_unlock(&delayed_root->lock);
 230
 231         return node;
 232 }
 233
 234 static struct btrfs_delayed_node *btrfs_next_delayed_node(
 235                                                 struct btrfs_delayed_node *node)
 236 {
 237         struct btrfs_delayed_root *delayed_root;
 238         struct list_head *p;
 239         struct btrfs_delayed_node *next = NULL;
 240
 241         delayed_root = node->root->fs_info->delayed_root;
 242         spin_lock(&delayed_root->lock);
 243         if (!test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 244                 /* not in the list */
 245                 if (list_empty(&delayed_root->node_list))
 246                         goto out;
 247                 p = delayed_root->node_list.next;
 248         } else if (list_is_last(&node->n_list, &delayed_root->node_list))
 249                 goto out;
 250         else
 251                 p = node->n_list.next;
 252
 253         next = list_entry(p, struct btrfs_delayed_node, n_list);
 254         refcount_inc(&next->refs);
 255 out:
 256         spin_unlock(&delayed_root->lock);
 257
 258         return next;
 259 }
 260
 261 static void __btrfs_release_delayed_node(
 262                                 struct btrfs_delayed_node *delayed_node,
 263                                 int mod)
 264 {
 265         struct btrfs_delayed_root *delayed_root;
 266
 267         if (!delayed_node)
 268                 return;
 269
 270         delayed_root = delayed_node->root->fs_info->delayed_root;
 271
 272         mutex_lock(&delayed_node->mutex);
 273         if (delayed_node->count)
 274                 btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
 275         else
 276                 btrfs_dequeue_delayed_node(delayed_root, delayed_node);
 277         mutex_unlock(&delayed_node->mutex);
 278
 279         if (refcount_dec_and_test(&delayed_node->refs)) {
 280                 struct btrfs_root *root = delayed_node->root;
 281
 282                 spin_lock(&root->inode_lock);
 283                 /*
 284                  * Once our refcount goes to zero, nobody is allowed to bump it
 285                  * back up.  We can delete it now.
 286                  */
 287                 ASSERT(refcount_read(&delayed_node->refs) == 0);
 288                 radix_tree_delete(&root->delayed_nodes_tree,
 289                                   delayed_node->inode_id);
 290                 spin_unlock(&root->inode_lock);
 291                 kmem_cache_free(delayed_node_cache, delayed_node);
 292         }
 293 }
 294
 295 static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 296 {
 297         __btrfs_release_delayed_node(node, 0);
 298 }
 299
 300 static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 301                                         struct btrfs_delayed_root *delayed_root)
 302 {
 303         struct list_head *p;
 304         struct btrfs_delayed_node *node = NULL;
 305
 306         spin_lock(&delayed_root->lock);
 307         if (list_empty(&delayed_root->prepare_list))
 308                 goto out;
 309
 310         p = delayed_root->prepare_list.next;
 311         list_del_init(p);
 312         node = list_entry(p, struct btrfs_delayed_node, p_list);
 313         refcount_inc(&node->refs);
 314 out:
 315         spin_unlock(&delayed_root->lock);
 316
 317         return node;
 318 }
 319
 320 static inline void btrfs_release_prepared_delayed_node(
 321                                         struct btrfs_delayed_node *node)
 322 {
 323         __btrfs_release_delayed_node(node, 1);
 324 }
 325
 326 static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
 327 {
 328         struct btrfs_delayed_item *item;
 329         item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
 330         if (item) {
 331                 item->data_len = data_len;
 332                 item->ins_or_del = 0;
 333                 item->bytes_reserved = 0;
 334                 item->delayed_node = NULL;
 335                 refcount_set(&item->refs, 1);
 336         }
 337         return item;
 338 }
 339
 340 /*
 341  * __btrfs_lookup_delayed_item - look up the delayed item by key
 342  * @delayed_node: pointer to the delayed node
 343  * @key:          the key to look up
 344  * @prev:         used to store the prev item if the right item isn't found
 345  * @next:         used to store the next item if the right item isn't found
 346  *
 347  * Note: if we don't find the right item, we will return the prev item and
 348  * the next item.
 349  */
 350 static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 351                                 struct rb_root *root,
 352                                 struct btrfs_key *key,
 353                                 struct btrfs_delayed_item **prev,
 354                                 struct btrfs_delayed_item **next)
 355 {
 356         struct rb_node *node, *prev_node = NULL;
 357         struct btrfs_delayed_item *delayed_item = NULL;
 358         int ret = 0;
 359
 360         node = root->rb_node;
 361
 362         while (node) {
 363                 delayed_item = rb_entry(node, struct btrfs_delayed_item,
 364                                         rb_node);
 365                 prev_node = node;
 366                 ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
 367                 if (ret < 0)
 368                         node = node->rb_right;
 369                 else if (ret > 0)
 370                         node = node->rb_left;
 371                 else
 372                         return delayed_item;
 373         }
 374
 375         if (prev) {
 376                 if (!prev_node)
 377                         *prev = NULL;
 378                 else if (ret < 0)
 379                         *prev = delayed_item;
 380                 else if ((node = rb_prev(prev_node)) != NULL) {
 381                         *prev = rb_entry(node, struct btrfs_delayed_item,
 382                                          rb_node);
 383                 } else
 384                         *prev = NULL;
 385         }
 386
 387         if (next) {
 388                 if (!prev_node)
 389                         *next = NULL;
 390                 else if (ret > 0)
 391                         *next = delayed_item;
 392                 else if ((node = rb_next(prev_node)) != NULL) {
 393                         *next = rb_entry(node, struct btrfs_delayed_item,
 394                                          rb_node);
 395                 } else
 396                         *next = NULL;
 397         }
 398         return NULL;
 399 }
 400
 401 static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
 402                                         struct btrfs_delayed_node *delayed_node,
 403                                         struct btrfs_key *key)
 404 {
 405         return __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
 406                                            NULL, NULL);
 407 }
 408
 409 static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 410                                     struct btrfs_delayed_item *ins,
 411                                     int action)
 412 {
 413         struct rb_node **p, *node;
 414         struct rb_node *parent_node = NULL;
 415         struct rb_root *root;
 416         struct btrfs_delayed_item *item;
 417         int cmp;
 418
 419         if (action == BTRFS_DELAYED_INSERTION_ITEM)
 420                 root = &delayed_node->ins_root;
 421         else if (action == BTRFS_DELAYED_DELETION_ITEM)
 422                 root = &delayed_node->del_root;
 423         else
 424                 BUG();
 425         p = &root->rb_node;
 426         node = &ins->rb_node;
 427
 428         while (*p) {
 429                 parent_node = *p;
 430                 item = rb_entry(parent_node, struct btrfs_delayed_item,
 431                                  rb_node);
 432
 433                 cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
 434                 if (cmp < 0)
 435                         p = &(*p)->rb_right;
 436                 else if (cmp > 0)
 437                         p = &(*p)->rb_left;
 438                 else
 439                         return -EEXIST;
 440         }
 441
 442         rb_link_node(node, parent_node, p);
 443         rb_insert_color(node, root);
 444         ins->delayed_node = delayed_node;
 445         ins->ins_or_del = action;
 446
 447         if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
 448             action == BTRFS_DELAYED_INSERTION_ITEM &&
 449             ins->key.offset >= delayed_node->index_cnt)
 450                         delayed_node->index_cnt = ins->key.offset + 1;
 451
 452         delayed_node->count++;
 453         atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 454         return 0;
 455 }
 456
 457 static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
 458                                               struct btrfs_delayed_item *item)
 459 {
 460         return __btrfs_add_delayed_item(node, item,
 461                                         BTRFS_DELAYED_INSERTION_ITEM);
 462 }
 463
 464 static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 465                                              struct btrfs_delayed_item *item)
 466 {
 467         return __btrfs_add_delayed_item(node, item,
 468                                         BTRFS_DELAYED_DELETION_ITEM);
 469 }
 470
 471 static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 472 {
 473         int seq = atomic_inc_return(&delayed_root->items_seq);
 474
 475         /*
 476          * atomic_dec_return implies a barrier for waitqueue_active
 477          */
 478         if ((atomic_dec_return(&delayed_root->items) <
 479             BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) &&
 480             waitqueue_active(&delayed_root->wait))
 481                 wake_up(&delayed_root->wait);
 482 }
 483
 484 static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 485 {
 486         struct rb_root *root;
 487         struct btrfs_delayed_root *delayed_root;
 488
 489         delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
 490
 491         BUG_ON(!delayed_root);
 492         BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
 493                delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
 494
 495         if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
 496                 root = &delayed_item->delayed_node->ins_root;
 497         else
 498                 root = &delayed_item->delayed_node->del_root;
 499
 500         rb_erase(&delayed_item->rb_node, root);
 501         delayed_item->delayed_node->count--;
 502
 503         finish_one_item(delayed_root);
 504 }
 505
 506 static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 507 {
 508         if (item) {
 509                 __btrfs_remove_delayed_item(item);
 510                 if (refcount_dec_and_test(&item->refs))
 511                         kfree(item);
 512         }
 513 }
 514
 515 static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
 516                                         struct btrfs_delayed_node *delayed_node)
 517 {
 518         struct rb_node *p;
 519         struct btrfs_delayed_item *item = NULL;
 520
 521         p = rb_first(&delayed_node->ins_root);
 522         if (p)
 523                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 524
 525         return item;
 526 }
 527
 528 static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 529                                         struct btrfs_delayed_node *delayed_node)
 530 {
 531         struct rb_node *p;
 532         struct btrfs_delayed_item *item = NULL;
 533
 534         p = rb_first(&delayed_node->del_root);
 535         if (p)
 536                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 537
 538         return item;
 539 }
 540
 541 static struct btrfs_delayed_item *__btrfs_next_delayed_item(
 542                                                 struct btrfs_delayed_item *item)
 543 {
 544         struct rb_node *p;
 545         struct btrfs_delayed_item *next = NULL;
 546
 547         p = rb_next(&item->rb_node);
 548         if (p)
 549                 next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 550
 551         return next;
 552 }
 553
 554 static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 555                                                struct btrfs_fs_info *fs_info,
 556                                                struct btrfs_delayed_item *item)
 557 {
 558         struct btrfs_block_rsv *src_rsv;
 559         struct btrfs_block_rsv *dst_rsv;
 560         u64 num_bytes;
 561         int ret;
 562
 563         if (!trans->bytes_reserved)
 564                 return 0;
 565
 566         src_rsv = trans->block_rsv;
 567         dst_rsv = &fs_info->delayed_block_rsv;
 568
 569         num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 570         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 571         if (!ret) {
 572                 trace_btrfs_space_reservation(fs_info, "delayed_item",
 573                                               item->key.objectid,
 574                                               num_bytes, 1);
 575                 item->bytes_reserved = num_bytes;
 576         }
 577
 578         return ret;
 579 }
 580
 581 static void btrfs_delayed_item_release_metadata(struct btrfs_fs_info *fs_info,
 582                                                 struct btrfs_delayed_item *item)
 583 {
 584         struct btrfs_block_rsv *rsv;
 585
 586         if (!item->bytes_reserved)
 587                 return;
 588
 589         rsv = &fs_info->delayed_block_rsv;
 590         trace_btrfs_space_reservation(fs_info, "delayed_item",
 591                                       item->key.objectid, item->bytes_reserved,
 592                                       0);
 593         btrfs_block_rsv_release(fs_info, rsv,
 594                                 item->bytes_reserved);
 595 }
 596
 597 static int btrfs_delayed_inode_reserve_metadata(
 598                                         struct btrfs_trans_handle *trans,
 599                                         struct btrfs_root *root,
 600                                         struct btrfs_inode *inode,
 601                                         struct btrfs_delayed_node *node)
 602 {
 603         struct btrfs_fs_info *fs_info = root->fs_info;
 604         struct btrfs_block_rsv *src_rsv;
 605         struct btrfs_block_rsv *dst_rsv;
 606         u64 num_bytes;
 607         int ret;
 608
 609         src_rsv = trans->block_rsv;
 610         dst_rsv = &fs_info->delayed_block_rsv;
 611
 612         num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 613
 614         /*
 615          * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 616          * which doesn't reserve space for speed.  This is a problem since we
 617          * still need to reserve space for this update, so try to reserve the
 618          * space.
 619          *
 620          * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
 621          * we always reserve enough to update the inode item.
 622          */
 623         if (!src_rsv || (!trans->bytes_reserved &&
 624                          src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
 625                 ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 626                                           BTRFS_RESERVE_NO_FLUSH);
 627                 /*
 628                  * Since we're under a transaction reserve_metadata_bytes could
 629                  * try to commit the transaction which will make it return
 630                  * EAGAIN to make us stop the transaction we have, so return
 631                  * ENOSPC instead so that btrfs_dirty_inode knows what to do.
 632                  */
 633                 if (ret == -EAGAIN)
 634                         ret = -ENOSPC;
 635                 if (!ret) {
 636                         node->bytes_reserved = num_bytes;
 637                         trace_btrfs_space_reservation(fs_info,
 638                                                       "delayed_inode",
 639                                                       btrfs_ino(inode),
 640                                                       num_bytes, 1);
 641                 }
 642                 return ret;
 643         }
 644
 645         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 646         if (!ret) {
 647                 trace_btrfs_space_reservation(fs_info, "delayed_inode",
 648                                               btrfs_ino(inode), num_bytes, 1);
 649                 node->bytes_reserved = num_bytes;
 650         }
 651
 652         return ret;
 653 }
 654
 655 static void btrfs_delayed_inode_release_metadata(struct btrfs_fs_info *fs_info,
 656                                                 struct btrfs_delayed_node *node)
 657 {
 658         struct btrfs_block_rsv *rsv;
 659
 660         if (!node->bytes_reserved)
 661                 return;
 662
 663         rsv = &fs_info->delayed_block_rsv;
 664         trace_btrfs_space_reservation(fs_info, "delayed_inode",
 665                                       node->inode_id, node->bytes_reserved, 0);
 666         btrfs_block_rsv_release(fs_info, rsv,
 667                                 node->bytes_reserved);
 668         node->bytes_reserved = 0;
 669 }
 670
 671 /*
 672  * This helper will insert some continuous items into the same leaf according
 673  * to the free space of the leaf.
 674  */
 675 static int btrfs_batch_insert_items(struct btrfs_root *root,
 676                                     struct btrfs_path *path,
 677                                     struct btrfs_delayed_item *item)
 678 {
 679         struct btrfs_fs_info *fs_info = root->fs_info;
 680         struct btrfs_delayed_item *curr, *next;
 681         int free_space;
 682         int total_data_size = 0, total_size = 0;
 683         struct extent_buffer *leaf;
 684         char *data_ptr;
 685         struct btrfs_key *keys;
 686         u32 *data_size;
 687         struct list_head head;
 688         int slot;
 689         int nitems;
 690         int i;
 691         int ret = 0;
 692
 693         BUG_ON(!path->nodes[0]);
 694
 695         leaf = path->nodes[0];
 696         free_space = btrfs_leaf_free_space(fs_info, leaf);
 697         INIT_LIST_HEAD(&head);
 698
 699         next = item;
 700         nitems = 0;
 701
 702         /*
 703          * count the number of the continuous items that we can insert in batch
 704          */
 705         while (total_size + next->data_len + sizeof(struct btrfs_item) <=
 706                free_space) {
 707                 total_data_size += next->data_len;
 708                 total_size += next->data_len + sizeof(struct btrfs_item);
 709                 list_add_tail(&next->tree_list, &head);
 710                 nitems++;
 711
 712                 curr = next;
 713                 next = __btrfs_next_delayed_item(curr);
 714                 if (!next)
 715                         break;
 716
 717                 if (!btrfs_is_continuous_delayed_item(curr, next))
 718                         break;
 719         }
 720
 721         if (!nitems) {
 722                 ret = 0;
 723                 goto out;
 724         }
 725
 726         /*
 727          * we need allocate some memory space, but it might cause the task
 728          * to sleep, so we set all locked nodes in the path to blocking locks
 729          * first.
 730          */
 731         btrfs_set_path_blocking(path);
 732
 733         keys = kmalloc_array(nitems, sizeof(struct btrfs_key), GFP_NOFS);
 734         if (!keys) {
 735                 ret = -ENOMEM;
 736                 goto out;
 737         }
 738
 739         data_size = kmalloc_array(nitems, sizeof(u32), GFP_NOFS);
 740         if (!data_size) {
 741                 ret = -ENOMEM;
 742                 goto error;
 743         }
 744
 745         /* get keys of all the delayed items */
 746         i = 0;
 747         list_for_each_entry(next, &head, tree_list) {
 748                 keys[i] = next->key;
 749                 data_size[i] = next->data_len;
 750                 i++;
 751         }
 752
 753         /* reset all the locked nodes in the patch to spinning locks. */
 754         btrfs_clear_path_blocking(path, NULL, 0);
 755
 756         /* insert the keys of the items */
 757         setup_items_for_insert(root, path, keys, data_size,
 758                                total_data_size, total_size, nitems);
 759
 760         /* insert the dir index items */
 761         slot = path->slots[0];
 762         list_for_each_entry_safe(curr, next, &head, tree_list) {
 763                 data_ptr = btrfs_item_ptr(leaf, slot, char);
 764                 write_extent_buffer(leaf, &curr->data,
 765                                     (unsigned long)data_ptr,
 766                                     curr->data_len);
 767                 slot++;
 768
 769                 btrfs_delayed_item_release_metadata(fs_info, curr);
 770
 771                 list_del(&curr->tree_list);
 772                 btrfs_release_delayed_item(curr);
 773         }
 774
 775 error:
 776         kfree(data_size);
 777         kfree(keys);
 778 out:
 779         return ret;
 780 }
 781
 782 /*
 783  * This helper can just do simple insertion that needn't extend item for new
 784  * data, such as directory name index insertion, inode insertion.
 785  */
 786 static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 787                                      struct btrfs_root *root,
 788                                      struct btrfs_path *path,
 789                                      struct btrfs_delayed_item *delayed_item)
 790 {
 791         struct btrfs_fs_info *fs_info = root->fs_info;
 792         struct extent_buffer *leaf;
 793         char *ptr;
 794         int ret;
 795
 796         ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
 797                                       delayed_item->data_len);
 798         if (ret < 0 && ret != -EEXIST)
 799                 return ret;
 800
 801         leaf = path->nodes[0];
 802
 803         ptr = btrfs_item_ptr(leaf, path->slots[0], char);
 804
 805         write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
 806                             delayed_item->data_len);
 807         btrfs_mark_buffer_dirty(leaf);
 808
 809         btrfs_delayed_item_release_metadata(fs_info, delayed_item);
 810         return 0;
 811 }
 812
 813 /*
 814  * we insert an item first, then if there are some continuous items, we try
 815  * to insert those items into the same leaf.
 816  */
 817 static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 818                                       struct btrfs_path *path,
 819                                       struct btrfs_root *root,
 820                                       struct btrfs_delayed_node *node)
 821 {
 822         struct btrfs_delayed_item *curr, *prev;
 823         int ret = 0;
 824
 825 do_again:
 826         mutex_lock(&node->mutex);
 827         curr = __btrfs_first_delayed_insertion_item(node);
 828         if (!curr)
 829                 goto insert_end;
 830
 831         ret = btrfs_insert_delayed_item(trans, root, path, curr);
 832         if (ret < 0) {
 833                 btrfs_release_path(path);
 834                 goto insert_end;
 835         }
 836
 837         prev = curr;
 838         curr = __btrfs_next_delayed_item(prev);
 839         if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
 840                 /* insert the continuous items into the same leaf */
 841                 path->slots[0]++;
 842                 btrfs_batch_insert_items(root, path, curr);
 843         }
 844         btrfs_release_delayed_item(prev);
 845         btrfs_mark_buffer_dirty(path->nodes[0]);
 846
 847         btrfs_release_path(path);
 848         mutex_unlock(&node->mutex);
 849         goto do_again;
 850
 851 insert_end:
 852         mutex_unlock(&node->mutex);
 853         return ret;
 854 }
 855
 856 static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
 857                                     struct btrfs_root *root,
 858                                     struct btrfs_path *path,
 859                                     struct btrfs_delayed_item *item)
 860 {
 861         struct btrfs_fs_info *fs_info = root->fs_info;
 862         struct btrfs_delayed_item *curr, *next;
 863         struct extent_buffer *leaf;
 864         struct btrfs_key key;
 865         struct list_head head;
 866         int nitems, i, last_item;
 867         int ret = 0;
 868
 869         BUG_ON(!path->nodes[0]);
 870
 871         leaf = path->nodes[0];
 872
 873         i = path->slots[0];
 874         last_item = btrfs_header_nritems(leaf) - 1;
 875         if (i > last_item)
 876                 return -ENOENT; /* FIXME: Is errno suitable? */
 877
 878         next = item;
 879         INIT_LIST_HEAD(&head);
 880         btrfs_item_key_to_cpu(leaf, &key, i);
 881         nitems = 0;
 882         /*
 883          * count the number of the dir index items that we can delete in batch
 884          */
 885         while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
 886                 list_add_tail(&next->tree_list, &head);
 887                 nitems++;
 888
 889                 curr = next;
 890                 next = __btrfs_next_delayed_item(curr);
 891                 if (!next)
 892                         break;
 893
 894                 if (!btrfs_is_continuous_delayed_item(curr, next))
 895                         break;
 896
 897                 i++;
 898                 if (i > last_item)
 899                         break;
 900                 btrfs_item_key_to_cpu(leaf, &key, i);
 901         }
 902
 903         if (!nitems)
 904                 return 0;
 905
 906         ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 907         if (ret)
 908                 goto out;
 909
 910         list_for_each_entry_safe(curr, next, &head, tree_list) {
 911                 btrfs_delayed_item_release_metadata(fs_info, curr);
 912                 list_del(&curr->tree_list);
 913                 btrfs_release_delayed_item(curr);
 914         }
 915
 916 out:
 917         return ret;
 918 }
 919
 920 static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 921                                       struct btrfs_path *path,
 922                                       struct btrfs_root *root,
 923                                       struct btrfs_delayed_node *node)
 924 {
 925         struct btrfs_delayed_item *curr, *prev;
 926         int ret = 0;
 927
 928 do_again:
 929         mutex_lock(&node->mutex);
 930         curr = __btrfs_first_delayed_deletion_item(node);
 931         if (!curr)
 932                 goto delete_fail;
 933
 934         ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
 935         if (ret < 0)
 936                 goto delete_fail;
 937         else if (ret > 0) {
 938                 /*
 939                  * can't find the item which the node points to, so this node
 940                  * is invalid, just drop it.
 941                  */
 942                 prev = curr;
 943                 curr = __btrfs_next_delayed_item(prev);
 944                 btrfs_release_delayed_item(prev);
 945                 ret = 0;
 946                 btrfs_release_path(path);
 947                 if (curr) {
 948                         mutex_unlock(&node->mutex);
 949                         goto do_again;
 950                 } else
 951                         goto delete_fail;
 952         }
 953
 954         btrfs_batch_delete_items(trans, root, path, curr);
 955         btrfs_release_path(path);
 956         mutex_unlock(&node->mutex);
 957         goto do_again;
 958
 959 delete_fail:
 960         btrfs_release_path(path);
 961         mutex_unlock(&node->mutex);
 962         return ret;
 963 }
 964
 965 static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
 966 {
 967         struct btrfs_delayed_root *delayed_root;
 968
 969         if (delayed_node &&
 970             test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
 971                 BUG_ON(!delayed_node->root);
 972                 clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
 973                 delayed_node->count--;
 974
 975                 delayed_root = delayed_node->root->fs_info->delayed_root;
 976                 finish_one_item(delayed_root);
 977         }
 978 }
 979
 980 static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
 981 {
 982         struct btrfs_delayed_root *delayed_root;
 983
 984         ASSERT(delayed_node->root);
 985         clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
 986         delayed_node->count--;
 987
 988         delayed_root = delayed_node->root->fs_info->delayed_root;
 989         finish_one_item(delayed_root);
 990 }
 991
 992 static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
 993                                         struct btrfs_root *root,
 994                                         struct btrfs_path *path,
 995                                         struct btrfs_delayed_node *node)
 996 {
 997         struct btrfs_fs_info *fs_info = root->fs_info;
 998         struct btrfs_key key;
 999         struct btrfs_inode_item *inode_item;
1000         struct extent_buffer *leaf;
1001         int mod;
1002         int ret;
1003
1004         key.objectid = node->inode_id;
1005         key.type = BTRFS_INODE_ITEM_KEY;
1006         key.offset = 0;
1007
1008         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1009                 mod = -1;
1010         else
1011                 mod = 1;
1012
1013         ret = btrfs_lookup_inode(trans, root, path, &key, mod);
1014         if (ret > 0) {
1015                 btrfs_release_path(path);
1016                 return -ENOENT;
1017         } else if (ret < 0) {
1018                 return ret;
1019         }
1020
1021         leaf = path->nodes[0];
1022         inode_item = btrfs_item_ptr(leaf, path->slots[0],
1023                                     struct btrfs_inode_item);
1024         write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1025                             sizeof(struct btrfs_inode_item));
1026         btrfs_mark_buffer_dirty(leaf);
1027
1028         if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1029                 goto no_iref;
1030
1031         path->slots[0]++;
1032         if (path->slots[0] >= btrfs_header_nritems(leaf))
1033                 goto search;
1034 again:
1035         btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1036         if (key.objectid != node->inode_id)
1037                 goto out;
1038
1039         if (key.type != BTRFS_INODE_REF_KEY &&
1040             key.type != BTRFS_INODE_EXTREF_KEY)
1041                 goto out;
1042
1043         /*
1044          * Delayed iref deletion is for the inode who has only one link,
1045          * so there is only one iref. The case that several irefs are
1046          * in the same item doesn't exist.
1047          */
1048         btrfs_del_item(trans, root, path);
1049 out:
1050         btrfs_release_delayed_iref(node);
1051 no_iref:
1052         btrfs_release_path(path);
1053 err_out:
1054         btrfs_delayed_inode_release_metadata(fs_info, node);
1055         btrfs_release_delayed_inode(node);
1056
1057         return ret;
1058
1059 search:
1060         btrfs_release_path(path);
1061
1062         key.type = BTRFS_INODE_EXTREF_KEY;
1063         key.offset = -1;
1064         ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1065         if (ret < 0)
1066                 goto err_out;
1067         ASSERT(ret);
1068
1069         ret = 0;
1070         leaf = path->nodes[0];
1071         path->slots[0]--;
1072         goto again;
1073 }
1074
1075 static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1076                                              struct btrfs_root *root,
1077                                              struct btrfs_path *path,
1078                                              struct btrfs_delayed_node *node)
1079 {
1080         int ret;
1081
1082         mutex_lock(&node->mutex);
1083         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
1084                 mutex_unlock(&node->mutex);
1085                 return 0;
1086         }
1087
1088         ret = __btrfs_update_delayed_inode(trans, root, path, node);
1089         mutex_unlock(&node->mutex);
1090         return ret;
1091 }
1092
1093 static inline int
1094 __btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1095                                    struct btrfs_path *path,
1096                                    struct btrfs_delayed_node *node)
1097 {
1098         int ret;
1099
1100         ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1101         if (ret)
1102                 return ret;
1103
1104         ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1105         if (ret)
1106                 return ret;
1107
1108         ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1109         return ret;
1110 }
1111
1112 /*
1113  * Called when committing the transaction.
1114  * Returns 0 on success.
1115  * Returns < 0 on error and returns with an aborted transaction with any
1116  * outstanding delayed items cleaned up.
1117  */
1118 static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1119                                      struct btrfs_fs_info *fs_info, int nr)
1120 {
1121         struct btrfs_delayed_root *delayed_root;
1122         struct btrfs_delayed_node *curr_node, *prev_node;
1123         struct btrfs_path *path;
1124         struct btrfs_block_rsv *block_rsv;
1125         int ret = 0;
1126         bool count = (nr > 0);
1127
1128         if (trans->aborted)
1129                 return -EIO;
1130
1131         path = btrfs_alloc_path();
1132         if (!path)
1133                 return -ENOMEM;
1134         path->leave_spinning = 1;
1135
1136         block_rsv = trans->block_rsv;
1137         trans->block_rsv = &fs_info->delayed_block_rsv;
1138
1139         delayed_root = fs_info->delayed_root;
1140
1141         curr_node = btrfs_first_delayed_node(delayed_root);
1142         while (curr_node && (!count || (count && nr--))) {
1143                 ret = __btrfs_commit_inode_delayed_items(trans, path,
1144                                                          curr_node);
1145                 if (ret) {
1146                         btrfs_release_delayed_node(curr_node);
1147                         curr_node = NULL;
1148                         btrfs_abort_transaction(trans, ret);
1149                         break;
1150                 }
1151
1152                 prev_node = curr_node;
1153                 curr_node = btrfs_next_delayed_node(curr_node);
1154                 btrfs_release_delayed_node(prev_node);
1155         }
1156
1157         if (curr_node)
1158                 btrfs_release_delayed_node(curr_node);
1159         btrfs_free_path(path);
1160         trans->block_rsv = block_rsv;
1161
1162         return ret;
1163 }
1164
1165 int btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1166                             struct btrfs_fs_info *fs_info)
1167 {
1168         return __btrfs_run_delayed_items(trans, fs_info, -1);
1169 }
1170
1171 int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans,
1172                                struct btrfs_fs_info *fs_info, int nr)
1173 {
1174         return __btrfs_run_delayed_items(trans, fs_info, nr);
1175 }
1176
1177 int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1178                                      struct btrfs_inode *inode)
1179 {
1180         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1181         struct btrfs_path *path;
1182         struct btrfs_block_rsv *block_rsv;
1183         int ret;
1184
1185         if (!delayed_node)
1186                 return 0;
1187
1188         mutex_lock(&delayed_node->mutex);
1189         if (!delayed_node->count) {
1190                 mutex_unlock(&delayed_node->mutex);
1191                 btrfs_release_delayed_node(delayed_node);
1192                 return 0;
1193         }
1194         mutex_unlock(&delayed_node->mutex);
1195
1196         path = btrfs_alloc_path();
1197         if (!path) {
1198                 btrfs_release_delayed_node(delayed_node);
1199                 return -ENOMEM;
1200         }
1201         path->leave_spinning = 1;
1202
1203         block_rsv = trans->block_rsv;
1204         trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1205
1206         ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1207
1208         btrfs_release_delayed_node(delayed_node);
1209         btrfs_free_path(path);
1210         trans->block_rsv = block_rsv;
1211
1212         return ret;
1213 }
1214
1215 int btrfs_commit_inode_delayed_inode(struct btrfs_inode *inode)
1216 {
1217         struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
1218         struct btrfs_trans_handle *trans;
1219         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1220         struct btrfs_path *path;
1221         struct btrfs_block_rsv *block_rsv;
1222         int ret;
1223
1224         if (!delayed_node)
1225                 return 0;
1226
1227         mutex_lock(&delayed_node->mutex);
1228         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1229                 mutex_unlock(&delayed_node->mutex);
1230                 btrfs_release_delayed_node(delayed_node);
1231                 return 0;
1232         }
1233         mutex_unlock(&delayed_node->mutex);
1234
1235         trans = btrfs_join_transaction(delayed_node->root);
1236         if (IS_ERR(trans)) {
1237                 ret = PTR_ERR(trans);
1238                 goto out;
1239         }
1240
1241         path = btrfs_alloc_path();
1242         if (!path) {
1243                 ret = -ENOMEM;
1244                 goto trans_out;
1245         }
1246         path->leave_spinning = 1;
1247
1248         block_rsv = trans->block_rsv;
1249         trans->block_rsv = &fs_info->delayed_block_rsv;
1250
1251         mutex_lock(&delayed_node->mutex);
1252         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
1253                 ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1254                                                    path, delayed_node);
1255         else
1256                 ret = 0;
1257         mutex_unlock(&delayed_node->mutex);
1258
1259         btrfs_free_path(path);
1260         trans->block_rsv = block_rsv;
1261 trans_out:
1262         btrfs_end_transaction(trans);
1263         btrfs_btree_balance_dirty(fs_info);
1264 out:
1265         btrfs_release_delayed_node(delayed_node);
1266
1267         return ret;
1268 }
1269
1270 void btrfs_remove_delayed_node(struct btrfs_inode *inode)
1271 {
1272         struct btrfs_delayed_node *delayed_node;
1273
1274         delayed_node = READ_ONCE(inode->delayed_node);
1275         if (!delayed_node)
1276                 return;
1277
1278         inode->delayed_node = NULL;
1279         btrfs_release_delayed_node(delayed_node);
1280 }
1281
1282 struct btrfs_async_delayed_work {
1283         struct btrfs_delayed_root *delayed_root;
1284         int nr;
1285         struct btrfs_work work;
1286 };
1287
1288 static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1289 {
1290         struct btrfs_async_delayed_work *async_work;
1291         struct btrfs_delayed_root *delayed_root;
1292         struct btrfs_trans_handle *trans;
1293         struct btrfs_path *path;
1294         struct btrfs_delayed_node *delayed_node = NULL;
1295         struct btrfs_root *root;
1296         struct btrfs_block_rsv *block_rsv;
1297         int total_done = 0;
1298
1299         async_work = container_of(work, struct btrfs_async_delayed_work, work);
1300         delayed_root = async_work->delayed_root;
1301
1302         path = btrfs_alloc_path();
1303         if (!path)
1304                 goto out;
1305
1306         do {
1307                 if (atomic_read(&delayed_root->items) <
1308                     BTRFS_DELAYED_BACKGROUND / 2)
1309                         break;
1310
1311                 delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1312                 if (!delayed_node)
1313                         break;
1314
1315                 path->leave_spinning = 1;
1316                 root = delayed_node->root;
1317
1318                 trans = btrfs_join_transaction(root);
1319                 if (IS_ERR(trans)) {
1320                         btrfs_release_path(path);
1321                         btrfs_release_prepared_delayed_node(delayed_node);
1322                         total_done++;
1323                         continue;
1324                 }
1325
1326                 block_rsv = trans->block_rsv;
1327                 trans->block_rsv = &root->fs_info->delayed_block_rsv;
1328
1329                 __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1330
1331                 trans->block_rsv = block_rsv;
1332                 btrfs_end_transaction(trans);
1333                 btrfs_btree_balance_dirty_nodelay(root->fs_info);
1334
1335                 btrfs_release_path(path);
1336                 btrfs_release_prepared_delayed_node(delayed_node);
1337                 total_done++;
1338
1339         } while ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK)
1340                  || total_done < async_work->nr);
1341
1342         btrfs_free_path(path);
1343 out:
1344         wake_up(&delayed_root->wait);
1345         kfree(async_work);
1346 }
1347
1348
1349 static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1350                                      struct btrfs_fs_info *fs_info, int nr)
1351 {
1352         struct btrfs_async_delayed_work *async_work;
1353
1354         async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
1355         if (!async_work)
1356                 return -ENOMEM;
1357
1358         async_work->delayed_root = delayed_root;
1359         btrfs_init_work(&async_work->work, btrfs_delayed_meta_helper,
1360                         btrfs_async_run_delayed_root, NULL, NULL);
1361         async_work->nr = nr;
1362
1363         btrfs_queue_work(fs_info->delayed_workers, &async_work->work);
1364         return 0;
1365 }
1366
1367 void btrfs_assert_delayed_root_empty(struct btrfs_fs_info *fs_info)
1368 {
1369         WARN_ON(btrfs_first_delayed_node(fs_info->delayed_root));
1370 }
1371
1372 static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
1373 {
1374         int val = atomic_read(&delayed_root->items_seq);
1375
1376         if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
1377                 return 1;
1378
1379         if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1380                 return 1;
1381
1382         return 0;
1383 }
1384
1385 void btrfs_balance_delayed_items(struct btrfs_fs_info *fs_info)
1386 {
1387         struct btrfs_delayed_root *delayed_root = fs_info->delayed_root;
1388
1389         if ((atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND) ||
1390                 btrfs_workqueue_normal_congested(fs_info->delayed_workers))
1391                 return;
1392
1393         if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1394                 int seq;
1395                 int ret;
1396
1397                 seq = atomic_read(&delayed_root->items_seq);
1398
1399                 ret = btrfs_wq_run_delayed_node(delayed_root, fs_info, 0);
1400                 if (ret)
1401                         return;
1402
1403                 wait_event_interruptible(delayed_root->wait,
1404                                          could_end_wait(delayed_root, seq));
1405                 return;
1406         }
1407
1408         btrfs_wq_run_delayed_node(delayed_root, fs_info, BTRFS_DELAYED_BATCH);
1409 }
1410
1411 /* Will return 0 or -ENOMEM */
1412 int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1413                                    struct btrfs_fs_info *fs_info,
1414                                    const char *name, int name_len,
1415                                    struct btrfs_inode *dir,
1416                                    struct btrfs_disk_key *disk_key, u8 type,
1417                                    u64 index)
1418 {
1419         struct btrfs_delayed_node *delayed_node;
1420         struct btrfs_delayed_item *delayed_item;
1421         struct btrfs_dir_item *dir_item;
1422         int ret;
1423
1424         delayed_node = btrfs_get_or_create_delayed_node(dir);
1425         if (IS_ERR(delayed_node))
1426                 return PTR_ERR(delayed_node);
1427
1428         delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
1429         if (!delayed_item) {
1430                 ret = -ENOMEM;
1431                 goto release_node;
1432         }
1433
1434         delayed_item->key.objectid = btrfs_ino(dir);
1435         delayed_item->key.type = BTRFS_DIR_INDEX_KEY;
1436         delayed_item->key.offset = index;
1437
1438         dir_item = (struct btrfs_dir_item *)delayed_item->data;
1439         dir_item->location = *disk_key;
1440         btrfs_set_stack_dir_transid(dir_item, trans->transid);
1441         btrfs_set_stack_dir_data_len(dir_item, 0);
1442         btrfs_set_stack_dir_name_len(dir_item, name_len);
1443         btrfs_set_stack_dir_type(dir_item, type);
1444         memcpy((char *)(dir_item + 1), name, name_len);
1445
1446         ret = btrfs_delayed_item_reserve_metadata(trans, fs_info, delayed_item);
1447         /*
1448          * we have reserved enough space when we start a new transaction,
1449          * so reserving metadata failure is impossible
1450          */
1451         BUG_ON(ret);
1452
1453
1454         mutex_lock(&delayed_node->mutex);
1455         ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1456         if (unlikely(ret)) {
1457                 btrfs_err(fs_info,
1458                           "err add delayed dir index item(name: %.*s) into the insertion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1459                           name_len, name, delayed_node->root->objectid,
1460                           delayed_node->inode_id, ret);
1461                 BUG();
1462         }
1463         mutex_unlock(&delayed_node->mutex);
1464
1465 release_node:
1466         btrfs_release_delayed_node(delayed_node);
1467         return ret;
1468 }
1469
1470 static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info,
1471                                                struct btrfs_delayed_node *node,
1472                                                struct btrfs_key *key)
1473 {
1474         struct btrfs_delayed_item *item;
1475
1476         mutex_lock(&node->mutex);
1477         item = __btrfs_lookup_delayed_insertion_item(node, key);
1478         if (!item) {
1479                 mutex_unlock(&node->mutex);
1480                 return 1;
1481         }
1482
1483         btrfs_delayed_item_release_metadata(fs_info, item);
1484         btrfs_release_delayed_item(item);
1485         mutex_unlock(&node->mutex);
1486         return 0;
1487 }
1488
1489 int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1490                                    struct btrfs_fs_info *fs_info,
1491                                    struct btrfs_inode *dir, u64 index)
1492 {
1493         struct btrfs_delayed_node *node;
1494         struct btrfs_delayed_item *item;
1495         struct btrfs_key item_key;
1496         int ret;
1497
1498         node = btrfs_get_or_create_delayed_node(dir);
1499         if (IS_ERR(node))
1500                 return PTR_ERR(node);
1501
1502         item_key.objectid = btrfs_ino(dir);
1503         item_key.type = BTRFS_DIR_INDEX_KEY;
1504         item_key.offset = index;
1505
1506         ret = btrfs_delete_delayed_insertion_item(fs_info, node, &item_key);
1507         if (!ret)
1508                 goto end;
1509
1510         item = btrfs_alloc_delayed_item(0);
1511         if (!item) {
1512                 ret = -ENOMEM;
1513                 goto end;
1514         }
1515
1516         item->key = item_key;
1517
1518         ret = btrfs_delayed_item_reserve_metadata(trans, fs_info, item);
1519         /*
1520          * we have reserved enough space when we start a new transaction,
1521          * so reserving metadata failure is impossible.
1522          */
1523         BUG_ON(ret);
1524
1525         mutex_lock(&node->mutex);
1526         ret = __btrfs_add_delayed_deletion_item(node, item);
1527         if (unlikely(ret)) {
1528                 btrfs_err(fs_info,
1529                           "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1530                           index, node->root->objectid, node->inode_id, ret);
1531                 BUG();
1532         }
1533         mutex_unlock(&node->mutex);
1534 end:
1535         btrfs_release_delayed_node(node);
1536         return ret;
1537 }
1538
1539 int btrfs_inode_delayed_dir_index_count(struct btrfs_inode *inode)
1540 {
1541         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1542
1543         if (!delayed_node)
1544                 return -ENOENT;
1545
1546         /*
1547          * Since we have held i_mutex of this directory, it is impossible that
1548          * a new directory index is added into the delayed node and index_cnt
1549          * is updated now. So we needn't lock the delayed node.
1550          */
1551         if (!delayed_node->index_cnt) {
1552                 btrfs_release_delayed_node(delayed_node);
1553                 return -EINVAL;
1554         }
1555
1556         inode->index_cnt = delayed_node->index_cnt;
1557         btrfs_release_delayed_node(delayed_node);
1558         return 0;
1559 }
1560
1561 bool btrfs_readdir_get_delayed_items(struct inode *inode,
1562                                      struct list_head *ins_list,
1563                                      struct list_head *del_list)
1564 {
1565         struct btrfs_delayed_node *delayed_node;
1566         struct btrfs_delayed_item *item;
1567
1568         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1569         if (!delayed_node)
1570                 return false;
1571
1572         /*
1573          * We can only do one readdir with delayed items at a time because of
1574          * item->readdir_list.
1575          */
1576         inode_unlock_shared(inode);
1577         inode_lock(inode);
1578
1579         mutex_lock(&delayed_node->mutex);
1580         item = __btrfs_first_delayed_insertion_item(delayed_node);
1581         while (item) {
1582                 refcount_inc(&item->refs);
1583                 list_add_tail(&item->readdir_list, ins_list);
1584                 item = __btrfs_next_delayed_item(item);
1585         }
1586
1587         item = __btrfs_first_delayed_deletion_item(delayed_node);
1588         while (item) {
1589                 refcount_inc(&item->refs);
1590                 list_add_tail(&item->readdir_list, del_list);
1591                 item = __btrfs_next_delayed_item(item);
1592         }
1593         mutex_unlock(&delayed_node->mutex);
1594         /*
1595          * This delayed node is still cached in the btrfs inode, so refs
1596          * must be > 1 now, and we needn't check it is going to be freed
1597          * or not.
1598          *
1599          * Besides that, this function is used to read dir, we do not
1600          * insert/delete delayed items in this period. So we also needn't
1601          * requeue or dequeue this delayed node.
1602          */
1603         refcount_dec(&delayed_node->refs);
1604
1605         return true;
1606 }
1607
1608 void btrfs_readdir_put_delayed_items(struct inode *inode,
1609                                      struct list_head *ins_list,
1610                                      struct list_head *del_list)
1611 {
1612         struct btrfs_delayed_item *curr, *next;
1613
1614         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1615                 list_del(&curr->readdir_list);
1616                 if (refcount_dec_and_test(&curr->refs))
1617                         kfree(curr);
1618         }
1619
1620         list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1621                 list_del(&curr->readdir_list);
1622                 if (refcount_dec_and_test(&curr->refs))
1623                         kfree(curr);
1624         }
1625
1626         /*
1627          * The VFS is going to do up_read(), so we need to downgrade back to a
1628          * read lock.
1629          */
1630         downgrade_write(&inode->i_rwsem);
1631 }
1632
1633 int btrfs_should_delete_dir_index(struct list_head *del_list,
1634                                   u64 index)
1635 {
1636         struct btrfs_delayed_item *curr;
1637         int ret = 0;
1638
1639         list_for_each_entry(curr, del_list, readdir_list) {
1640                 if (curr->key.offset > index)
1641                         break;
1642                 if (curr->key.offset == index) {
1643                         ret = 1;
1644                         break;
1645                 }
1646         }
1647         return ret;
1648 }
1649
1650 /*
1651  * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1652  *
1653  */
1654 int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
1655                                     struct list_head *ins_list)
1656 {
1657         struct btrfs_dir_item *di;
1658         struct btrfs_delayed_item *curr, *next;
1659         struct btrfs_key location;
1660         char *name;
1661         int name_len;
1662         int over = 0;
1663         unsigned char d_type;
1664
1665         if (list_empty(ins_list))
1666                 return 0;
1667
1668         /*
1669          * Changing the data of the delayed item is impossible. So
1670          * we needn't lock them. And we have held i_mutex of the
1671          * directory, nobody can delete any directory indexes now.
1672          */
1673         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1674                 list_del(&curr->readdir_list);
1675
1676                 if (curr->key.offset < ctx->pos) {
1677                         if (refcount_dec_and_test(&curr->refs))
1678                                 kfree(curr);
1679                         continue;
1680                 }
1681
1682                 ctx->pos = curr->key.offset;
1683
1684                 di = (struct btrfs_dir_item *)curr->data;
1685                 name = (char *)(di + 1);
1686                 name_len = btrfs_stack_dir_name_len(di);
1687
1688                 d_type = btrfs_filetype_table[di->type];
1689                 btrfs_disk_key_to_cpu(&location, &di->location);
1690
1691                 over = !dir_emit(ctx, name, name_len,
1692                                location.objectid, d_type);
1693
1694                 if (refcount_dec_and_test(&curr->refs))
1695                         kfree(curr);
1696
1697                 if (over)
1698                         return 1;
1699                 ctx->pos++;
1700         }
1701         return 0;
1702 }
1703
1704 static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1705                                   struct btrfs_inode_item *inode_item,
1706                                   struct inode *inode)
1707 {
1708         btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1709         btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1710         btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1711         btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1712         btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1713         btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1714         btrfs_set_stack_inode_generation(inode_item,
1715                                          BTRFS_I(inode)->generation);
1716         btrfs_set_stack_inode_sequence(inode_item,
1717                                        inode_peek_iversion(inode));
1718         btrfs_set_stack_inode_transid(inode_item, trans->transid);
1719         btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1720         btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
1721         btrfs_set_stack_inode_block_group(inode_item, 0);
1722
1723         btrfs_set_stack_timespec_sec(&inode_item->atime,
1724                                      inode->i_atime.tv_sec);
1725         btrfs_set_stack_timespec_nsec(&inode_item->atime,
1726                                       inode->i_atime.tv_nsec);
1727
1728         btrfs_set_stack_timespec_sec(&inode_item->mtime,
1729                                      inode->i_mtime.tv_sec);
1730         btrfs_set_stack_timespec_nsec(&inode_item->mtime,
1731                                       inode->i_mtime.tv_nsec);
1732
1733         btrfs_set_stack_timespec_sec(&inode_item->ctime,
1734                                      inode->i_ctime.tv_sec);
1735         btrfs_set_stack_timespec_nsec(&inode_item->ctime,
1736                                       inode->i_ctime.tv_nsec);
1737
1738         btrfs_set_stack_timespec_sec(&inode_item->otime,
1739                                      BTRFS_I(inode)->i_otime.tv_sec);
1740         btrfs_set_stack_timespec_nsec(&inode_item->otime,
1741                                      BTRFS_I(inode)->i_otime.tv_nsec);
1742 }
1743
1744 int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1745 {
1746         struct btrfs_delayed_node *delayed_node;
1747         struct btrfs_inode_item *inode_item;
1748
1749         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1750         if (!delayed_node)
1751                 return -ENOENT;
1752
1753         mutex_lock(&delayed_node->mutex);
1754         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1755                 mutex_unlock(&delayed_node->mutex);
1756                 btrfs_release_delayed_node(delayed_node);
1757                 return -ENOENT;
1758         }
1759
1760         inode_item = &delayed_node->inode_item;
1761
1762         i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1763         i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1764         btrfs_i_size_write(BTRFS_I(inode), btrfs_stack_inode_size(inode_item));
1765         inode->i_mode = btrfs_stack_inode_mode(inode_item);
1766         set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1767         inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1768         BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1769         BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
1770
1771         inode_set_iversion_queried(inode,
1772                                    btrfs_stack_inode_sequence(inode_item));
1773         inode->i_rdev = 0;
1774         *rdev = btrfs_stack_inode_rdev(inode_item);
1775         BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
1776
1777         inode->i_atime.tv_sec = btrfs_stack_timespec_sec(&inode_item->atime);
1778         inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->atime);
1779
1780         inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(&inode_item->mtime);
1781         inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->mtime);
1782
1783         inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(&inode_item->ctime);
1784         inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->ctime);
1785
1786         BTRFS_I(inode)->i_otime.tv_sec =
1787                 btrfs_stack_timespec_sec(&inode_item->otime);
1788         BTRFS_I(inode)->i_otime.tv_nsec =
1789                 btrfs_stack_timespec_nsec(&inode_item->otime);
1790
1791         inode->i_generation = BTRFS_I(inode)->generation;
1792         BTRFS_I(inode)->index_cnt = (u64)-1;
1793
1794         mutex_unlock(&delayed_node->mutex);
1795         btrfs_release_delayed_node(delayed_node);
1796         return 0;
1797 }
1798
1799 int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1800                                struct btrfs_root *root, struct inode *inode)
1801 {
1802         struct btrfs_delayed_node *delayed_node;
1803         int ret = 0;
1804
1805         delayed_node = btrfs_get_or_create_delayed_node(BTRFS_I(inode));
1806         if (IS_ERR(delayed_node))
1807                 return PTR_ERR(delayed_node);
1808
1809         mutex_lock(&delayed_node->mutex);
1810         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1811                 fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1812                 goto release_node;
1813         }
1814
1815         ret = btrfs_delayed_inode_reserve_metadata(trans, root, BTRFS_I(inode),
1816                                                    delayed_node);
1817         if (ret)
1818                 goto release_node;
1819
1820         fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1821         set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1822         delayed_node->count++;
1823         atomic_inc(&root->fs_info->delayed_root->items);
1824 release_node:
1825         mutex_unlock(&delayed_node->mutex);
1826         btrfs_release_delayed_node(delayed_node);
1827         return ret;
1828 }
1829
1830 int btrfs_delayed_delete_inode_ref(struct btrfs_inode *inode)
1831 {
1832         struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
1833         struct btrfs_delayed_node *delayed_node;
1834
1835         /*
1836          * we don't do delayed inode updates during log recovery because it
1837          * leads to enospc problems.  This means we also can't do
1838          * delayed inode refs
1839          */
1840         if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
1841                 return -EAGAIN;
1842
1843         delayed_node = btrfs_get_or_create_delayed_node(inode);
1844         if (IS_ERR(delayed_node))
1845                 return PTR_ERR(delayed_node);
1846
1847         /*
1848          * We don't reserve space for inode ref deletion is because:
1849          * - We ONLY do async inode ref deletion for the inode who has only
1850          *   one link(i_nlink == 1), it means there is only one inode ref.
1851          *   And in most case, the inode ref and the inode item are in the
1852          *   same leaf, and we will deal with them at the same time.
1853          *   Since we are sure we will reserve the space for the inode item,
1854          *   it is unnecessary to reserve space for inode ref deletion.
1855          * - If the inode ref and the inode item are not in the same leaf,
1856          *   We also needn't worry about enospc problem, because we reserve
1857          *   much more space for the inode update than it needs.
1858          * - At the worst, we can steal some space from the global reservation.
1859          *   It is very rare.
1860          */
1861         mutex_lock(&delayed_node->mutex);
1862         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1863                 goto release_node;
1864
1865         set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1866         delayed_node->count++;
1867         atomic_inc(&fs_info->delayed_root->items);
1868 release_node:
1869         mutex_unlock(&delayed_node->mutex);
1870         btrfs_release_delayed_node(delayed_node);
1871         return 0;
1872 }
1873
1874 static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1875 {
1876         struct btrfs_root *root = delayed_node->root;
1877         struct btrfs_fs_info *fs_info = root->fs_info;
1878         struct btrfs_delayed_item *curr_item, *prev_item;
1879
1880         mutex_lock(&delayed_node->mutex);
1881         curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1882         while (curr_item) {
1883                 btrfs_delayed_item_release_metadata(fs_info, curr_item);
1884                 prev_item = curr_item;
1885                 curr_item = __btrfs_next_delayed_item(prev_item);
1886                 btrfs_release_delayed_item(prev_item);
1887         }
1888
1889         curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1890         while (curr_item) {
1891                 btrfs_delayed_item_release_metadata(fs_info, 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         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1898                 btrfs_release_delayed_iref(delayed_node);
1899
1900         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1901                 btrfs_delayed_inode_release_metadata(fs_info, delayed_node);
1902                 btrfs_release_delayed_inode(delayed_node);
1903         }
1904         mutex_unlock(&delayed_node->mutex);
1905 }
1906
1907 void btrfs_kill_delayed_inode_items(struct btrfs_inode *inode)
1908 {
1909         struct btrfs_delayed_node *delayed_node;
1910
1911         delayed_node = btrfs_get_delayed_node(inode);
1912         if (!delayed_node)
1913                 return;
1914
1915         __btrfs_kill_delayed_node(delayed_node);
1916         btrfs_release_delayed_node(delayed_node);
1917 }
1918
1919 void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1920 {
1921         u64 inode_id = 0;
1922         struct btrfs_delayed_node *delayed_nodes[8];
1923         int i, n;
1924
1925         while (1) {
1926                 spin_lock(&root->inode_lock);
1927                 n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1928                                            (void **)delayed_nodes, inode_id,
1929                                            ARRAY_SIZE(delayed_nodes));
1930                 if (!n) {
1931                         spin_unlock(&root->inode_lock);
1932                         break;
1933                 }
1934
1935                 inode_id = delayed_nodes[n - 1]->inode_id + 1;
1936
1937                 for (i = 0; i < n; i++)
1938                         refcount_inc(&delayed_nodes[i]->refs);
1939                 spin_unlock(&root->inode_lock);
1940
1941                 for (i = 0; i < n; i++) {
1942                         __btrfs_kill_delayed_node(delayed_nodes[i]);
1943                         btrfs_release_delayed_node(delayed_nodes[i]);
1944                 }
1945         }
1946 }
1947
1948 void btrfs_destroy_delayed_inodes(struct btrfs_fs_info *fs_info)
1949 {
1950         struct btrfs_delayed_node *curr_node, *prev_node;
1951
1952         curr_node = btrfs_first_delayed_node(fs_info->delayed_root);
1953         while (curr_node) {
1954                 __btrfs_kill_delayed_node(curr_node);
1955
1956                 prev_node = curr_node;
1957                 curr_node = btrfs_next_delayed_node(curr_node);
1958                 btrfs_release_delayed_node(prev_node);
1959         }
1960 }
1961