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 <miaox@cn.fujitsu.com>
   5  */
   6
   7 #include <linux/slab.h>
   8 #include <linux/iversion.h>
   9 #include "misc.h"
  10 #include "delayed-inode.h"
  11 #include "disk-io.h"
  12 #include "transaction.h"
  13 #include "ctree.h"
  14 #include "qgroup.h"
  15 #include "locking.h"
  16
  17 #define BTRFS_DELAYED_WRITEBACK         512
  18 #define BTRFS_DELAYED_BACKGROUND        128
  19 #define BTRFS_DELAYED_BATCH             16
  20
  21 static struct kmem_cache *delayed_node_cache;
  22
  23 int __init btrfs_delayed_inode_init(void)
  24 {
  25         delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
  26                                         sizeof(struct btrfs_delayed_node),
  27                                         0,
  28                                         SLAB_MEM_SPREAD,
  29                                         NULL);
  30         if (!delayed_node_cache)
  31                 return -ENOMEM;
  32         return 0;
  33 }
  34
  35 void __cold btrfs_delayed_inode_exit(void)
  36 {
  37         kmem_cache_destroy(delayed_node_cache);
  38 }
  39
  40 static inline void btrfs_init_delayed_node(
  41                                 struct btrfs_delayed_node *delayed_node,
  42                                 struct btrfs_root *root, u64 inode_id)
  43 {
  44         delayed_node->root = root;
  45         delayed_node->inode_id = inode_id;
  46         refcount_set(&delayed_node->refs, 0);
  47         delayed_node->ins_root = RB_ROOT_CACHED;
  48         delayed_node->del_root = RB_ROOT_CACHED;
  49         mutex_init(&delayed_node->mutex);
  50         INIT_LIST_HEAD(&delayed_node->n_list);
  51         INIT_LIST_HEAD(&delayed_node->p_list);
  52 }
  53
  54 static inline int btrfs_is_continuous_delayed_item(
  55                                         struct btrfs_delayed_item *item1,
  56                                         struct btrfs_delayed_item *item2)
  57 {
  58         if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
  59             item1->key.objectid == item2->key.objectid &&
  60             item1->key.type == item2->key.type &&
  61             item1->key.offset + 1 == item2->key.offset)
  62                 return 1;
  63         return 0;
  64 }
  65
  66 static struct btrfs_delayed_node *btrfs_get_delayed_node(
  67                 struct btrfs_inode *btrfs_inode)
  68 {
  69         struct btrfs_root *root = btrfs_inode->root;
  70         u64 ino = btrfs_ino(btrfs_inode);
  71         struct btrfs_delayed_node *node;
  72
  73         node = READ_ONCE(btrfs_inode->delayed_node);
  74         if (node) {
  75                 refcount_inc(&node->refs);
  76                 return node;
  77         }
  78
  79         spin_lock(&root->inode_lock);
  80         node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
  81
  82         if (node) {
  83                 if (btrfs_inode->delayed_node) {
  84                         refcount_inc(&node->refs);      /* can be accessed */
  85                         BUG_ON(btrfs_inode->delayed_node != node);
  86                         spin_unlock(&root->inode_lock);
  87                         return node;
  88                 }
  89
  90                 /*
  91                  * It's possible that we're racing into the middle of removing
  92                  * this node from the radix tree.  In this case, the refcount
  93                  * was zero and it should never go back to one.  Just return
  94                  * NULL like it was never in the radix at all; our release
  95                  * function is in the process of removing it.
  96                  *
  97                  * Some implementations of refcount_inc refuse to bump the
  98                  * refcount once it has hit zero.  If we don't do this dance
  99                  * here, refcount_inc() may decide to just WARN_ONCE() instead
 100                  * of actually bumping the refcount.
 101                  *
 102                  * If this node is properly in the radix, we want to bump the
 103                  * refcount twice, once for the inode and once for this get
 104                  * operation.
 105                  */
 106                 if (refcount_inc_not_zero(&node->refs)) {
 107                         refcount_inc(&node->refs);
 108                         btrfs_inode->delayed_node = node;
 109                 } else {
 110                         node = NULL;
 111                 }
 112
 113                 spin_unlock(&root->inode_lock);
 114                 return node;
 115         }
 116         spin_unlock(&root->inode_lock);
 117
 118         return NULL;
 119 }
 120
 121 /* Will return either the node or PTR_ERR(-ENOMEM) */
 122 static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 123                 struct btrfs_inode *btrfs_inode)
 124 {
 125         struct btrfs_delayed_node *node;
 126         struct btrfs_root *root = btrfs_inode->root;
 127         u64 ino = btrfs_ino(btrfs_inode);
 128         int ret;
 129
 130 again:
 131         node = btrfs_get_delayed_node(btrfs_inode);
 132         if (node)
 133                 return node;
 134
 135         node = kmem_cache_zalloc(delayed_node_cache, GFP_NOFS);
 136         if (!node)
 137                 return ERR_PTR(-ENOMEM);
 138         btrfs_init_delayed_node(node, root, ino);
 139
 140         /* cached in the btrfs inode and can be accessed */
 141         refcount_set(&node->refs, 2);
 142
 143         ret = radix_tree_preload(GFP_NOFS);
 144         if (ret) {
 145                 kmem_cache_free(delayed_node_cache, node);
 146                 return ERR_PTR(ret);
 147         }
 148
 149         spin_lock(&root->inode_lock);
 150         ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
 151         if (ret == -EEXIST) {
 152                 spin_unlock(&root->inode_lock);
 153                 kmem_cache_free(delayed_node_cache, node);
 154                 radix_tree_preload_end();
 155                 goto again;
 156         }
 157         btrfs_inode->delayed_node = node;
 158         spin_unlock(&root->inode_lock);
 159         radix_tree_preload_end();
 160
 161         return node;
 162 }
 163
 164 /*
 165  * Call it when holding delayed_node->mutex
 166  *
 167  * If mod = 1, add this node into the prepared list.
 168  */
 169 static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
 170                                      struct btrfs_delayed_node *node,
 171                                      int mod)
 172 {
 173         spin_lock(&root->lock);
 174         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 175                 if (!list_empty(&node->p_list))
 176                         list_move_tail(&node->p_list, &root->prepare_list);
 177                 else if (mod)
 178                         list_add_tail(&node->p_list, &root->prepare_list);
 179         } else {
 180                 list_add_tail(&node->n_list, &root->node_list);
 181                 list_add_tail(&node->p_list, &root->prepare_list);
 182                 refcount_inc(&node->refs);      /* inserted into list */
 183                 root->nodes++;
 184                 set_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 185         }
 186         spin_unlock(&root->lock);
 187 }
 188
 189 /* Call it when holding delayed_node->mutex */
 190 static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
 191                                        struct btrfs_delayed_node *node)
 192 {
 193         spin_lock(&root->lock);
 194         if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 195                 root->nodes--;
 196                 refcount_dec(&node->refs);      /* not in the list */
 197                 list_del_init(&node->n_list);
 198                 if (!list_empty(&node->p_list))
 199                         list_del_init(&node->p_list);
 200                 clear_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 201         }
 202         spin_unlock(&root->lock);
 203 }
 204
 205 static struct btrfs_delayed_node *btrfs_first_delayed_node(
 206                         struct btrfs_delayed_root *delayed_root)
 207 {
 208         struct list_head *p;
 209         struct btrfs_delayed_node *node = NULL;
 210
 211         spin_lock(&delayed_root->lock);
 212         if (list_empty(&delayed_root->node_list))
 213                 goto out;
 214
 215         p = delayed_root->node_list.next;
 216         node = list_entry(p, struct btrfs_delayed_node, n_list);
 217         refcount_inc(&node->refs);
 218 out:
 219         spin_unlock(&delayed_root->lock);
 220
 221         return node;
 222 }
 223
 224 static struct btrfs_delayed_node *btrfs_next_delayed_node(
 225                                                 struct btrfs_delayed_node *node)
 226 {
 227         struct btrfs_delayed_root *delayed_root;
 228         struct list_head *p;
 229         struct btrfs_delayed_node *next = NULL;
 230
 231         delayed_root = node->root->fs_info->delayed_root;
 232         spin_lock(&delayed_root->lock);
 233         if (!test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 234                 /* not in the list */
 235                 if (list_empty(&delayed_root->node_list))
 236                         goto out;
 237                 p = delayed_root->node_list.next;
 238         } else if (list_is_last(&node->n_list, &delayed_root->node_list))
 239                 goto out;
 240         else
 241                 p = node->n_list.next;
 242
 243         next = list_entry(p, struct btrfs_delayed_node, n_list);
 244         refcount_inc(&next->refs);
 245 out:
 246         spin_unlock(&delayed_root->lock);
 247
 248         return next;
 249 }
 250
 251 static void __btrfs_release_delayed_node(
 252                                 struct btrfs_delayed_node *delayed_node,
 253                                 int mod)
 254 {
 255         struct btrfs_delayed_root *delayed_root;
 256
 257         if (!delayed_node)
 258                 return;
 259
 260         delayed_root = delayed_node->root->fs_info->delayed_root;
 261
 262         mutex_lock(&delayed_node->mutex);
 263         if (delayed_node->count)
 264                 btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
 265         else
 266                 btrfs_dequeue_delayed_node(delayed_root, delayed_node);
 267         mutex_unlock(&delayed_node->mutex);
 268
 269         if (refcount_dec_and_test(&delayed_node->refs)) {
 270                 struct btrfs_root *root = delayed_node->root;
 271
 272                 spin_lock(&root->inode_lock);
 273                 /*
 274                  * Once our refcount goes to zero, nobody is allowed to bump it
 275                  * back up.  We can delete it now.
 276                  */
 277                 ASSERT(refcount_read(&delayed_node->refs) == 0);
 278                 radix_tree_delete(&root->delayed_nodes_tree,
 279                                   delayed_node->inode_id);
 280                 spin_unlock(&root->inode_lock);
 281                 kmem_cache_free(delayed_node_cache, delayed_node);
 282         }
 283 }
 284
 285 static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 286 {
 287         __btrfs_release_delayed_node(node, 0);
 288 }
 289
 290 static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 291                                         struct btrfs_delayed_root *delayed_root)
 292 {
 293         struct list_head *p;
 294         struct btrfs_delayed_node *node = NULL;
 295
 296         spin_lock(&delayed_root->lock);
 297         if (list_empty(&delayed_root->prepare_list))
 298                 goto out;
 299
 300         p = delayed_root->prepare_list.next;
 301         list_del_init(p);
 302         node = list_entry(p, struct btrfs_delayed_node, p_list);
 303         refcount_inc(&node->refs);
 304 out:
 305         spin_unlock(&delayed_root->lock);
 306
 307         return node;
 308 }
 309
 310 static inline void btrfs_release_prepared_delayed_node(
 311                                         struct btrfs_delayed_node *node)
 312 {
 313         __btrfs_release_delayed_node(node, 1);
 314 }
 315
 316 static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
 317 {
 318         struct btrfs_delayed_item *item;
 319         item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
 320         if (item) {
 321                 item->data_len = data_len;
 322                 item->ins_or_del = 0;
 323                 item->bytes_reserved = 0;
 324                 item->delayed_node = NULL;
 325                 refcount_set(&item->refs, 1);
 326         }
 327         return item;
 328 }
 329
 330 /*
 331  * __btrfs_lookup_delayed_item - look up the delayed item by key
 332  * @delayed_node: pointer to the delayed node
 333  * @key:          the key to look up
 334  * @prev:         used to store the prev item if the right item isn't found
 335  * @next:         used to store the next item if the right item isn't found
 336  *
 337  * Note: if we don't find the right item, we will return the prev item and
 338  * the next item.
 339  */
 340 static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 341                                 struct rb_root *root,
 342                                 struct btrfs_key *key,
 343                                 struct btrfs_delayed_item **prev,
 344                                 struct btrfs_delayed_item **next)
 345 {
 346         struct rb_node *node, *prev_node = NULL;
 347         struct btrfs_delayed_item *delayed_item = NULL;
 348         int ret = 0;
 349
 350         node = root->rb_node;
 351
 352         while (node) {
 353                 delayed_item = rb_entry(node, struct btrfs_delayed_item,
 354                                         rb_node);
 355                 prev_node = node;
 356                 ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
 357                 if (ret < 0)
 358                         node = node->rb_right;
 359                 else if (ret > 0)
 360                         node = node->rb_left;
 361                 else
 362                         return delayed_item;
 363         }
 364
 365         if (prev) {
 366                 if (!prev_node)
 367                         *prev = NULL;
 368                 else if (ret < 0)
 369                         *prev = delayed_item;
 370                 else if ((node = rb_prev(prev_node)) != NULL) {
 371                         *prev = rb_entry(node, struct btrfs_delayed_item,
 372                                          rb_node);
 373                 } else
 374                         *prev = NULL;
 375         }
 376
 377         if (next) {
 378                 if (!prev_node)
 379                         *next = NULL;
 380                 else if (ret > 0)
 381                         *next = delayed_item;
 382                 else if ((node = rb_next(prev_node)) != NULL) {
 383                         *next = rb_entry(node, struct btrfs_delayed_item,
 384                                          rb_node);
 385                 } else
 386                         *next = NULL;
 387         }
 388         return NULL;
 389 }
 390
 391 static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
 392                                         struct btrfs_delayed_node *delayed_node,
 393                                         struct btrfs_key *key)
 394 {
 395         return __btrfs_lookup_delayed_item(&delayed_node->ins_root.rb_root, key,
 396                                            NULL, NULL);
 397 }
 398
 399 static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 400                                     struct btrfs_delayed_item *ins,
 401                                     int action)
 402 {
 403         struct rb_node **p, *node;
 404         struct rb_node *parent_node = NULL;
 405         struct rb_root_cached *root;
 406         struct btrfs_delayed_item *item;
 407         int cmp;
 408         bool leftmost = true;
 409
 410         if (action == BTRFS_DELAYED_INSERTION_ITEM)
 411                 root = &delayed_node->ins_root;
 412         else if (action == BTRFS_DELAYED_DELETION_ITEM)
 413                 root = &delayed_node->del_root;
 414         else
 415                 BUG();
 416         p = &root->rb_root.rb_node;
 417         node = &ins->rb_node;
 418
 419         while (*p) {
 420                 parent_node = *p;
 421                 item = rb_entry(parent_node, struct btrfs_delayed_item,
 422                                  rb_node);
 423
 424                 cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
 425                 if (cmp < 0) {
 426                         p = &(*p)->rb_right;
 427                         leftmost = false;
 428                 } else if (cmp > 0) {
 429                         p = &(*p)->rb_left;
 430                 } else {
 431                         return -EEXIST;
 432                 }
 433         }
 434
 435         rb_link_node(node, parent_node, p);
 436         rb_insert_color_cached(node, root, leftmost);
 437         ins->delayed_node = delayed_node;
 438         ins->ins_or_del = action;
 439
 440         if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
 441             action == BTRFS_DELAYED_INSERTION_ITEM &&
 442             ins->key.offset >= delayed_node->index_cnt)
 443                         delayed_node->index_cnt = ins->key.offset + 1;
 444
 445         delayed_node->count++;
 446         atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 447         return 0;
 448 }
 449
 450 static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
 451                                               struct btrfs_delayed_item *item)
 452 {
 453         return __btrfs_add_delayed_item(node, item,
 454                                         BTRFS_DELAYED_INSERTION_ITEM);
 455 }
 456
 457 static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 458                                              struct btrfs_delayed_item *item)
 459 {
 460         return __btrfs_add_delayed_item(node, item,
 461                                         BTRFS_DELAYED_DELETION_ITEM);
 462 }
 463
 464 static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 465 {
 466         int seq = atomic_inc_return(&delayed_root->items_seq);
 467
 468         /* atomic_dec_return implies a barrier */
 469         if ((atomic_dec_return(&delayed_root->items) <
 470             BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0))
 471                 cond_wake_up_nomb(&delayed_root->wait);
 472 }
 473
 474 static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 475 {
 476         struct rb_root_cached *root;
 477         struct btrfs_delayed_root *delayed_root;
 478
 479         /* Not associated with any delayed_node */
 480         if (!delayed_item->delayed_node)
 481                 return;
 482         delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
 483
 484         BUG_ON(!delayed_root);
 485         BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
 486                delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
 487
 488         if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
 489                 root = &delayed_item->delayed_node->ins_root;
 490         else
 491                 root = &delayed_item->delayed_node->del_root;
 492
 493         rb_erase_cached(&delayed_item->rb_node, root);
 494         delayed_item->delayed_node->count--;
 495
 496         finish_one_item(delayed_root);
 497 }
 498
 499 static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 500 {
 501         if (item) {
 502                 __btrfs_remove_delayed_item(item);
 503                 if (refcount_dec_and_test(&item->refs))
 504                         kfree(item);
 505         }
 506 }
 507
 508 static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
 509                                         struct btrfs_delayed_node *delayed_node)
 510 {
 511         struct rb_node *p;
 512         struct btrfs_delayed_item *item = NULL;
 513
 514         p = rb_first_cached(&delayed_node->ins_root);
 515         if (p)
 516                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 517
 518         return item;
 519 }
 520
 521 static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 522                                         struct btrfs_delayed_node *delayed_node)
 523 {
 524         struct rb_node *p;
 525         struct btrfs_delayed_item *item = NULL;
 526
 527         p = rb_first_cached(&delayed_node->del_root);
 528         if (p)
 529                 item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 530
 531         return item;
 532 }
 533
 534 static struct btrfs_delayed_item *__btrfs_next_delayed_item(
 535                                                 struct btrfs_delayed_item *item)
 536 {
 537         struct rb_node *p;
 538         struct btrfs_delayed_item *next = NULL;
 539
 540         p = rb_next(&item->rb_node);
 541         if (p)
 542                 next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 543
 544         return next;
 545 }
 546
 547 static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 548                                                struct btrfs_root *root,
 549                                                struct btrfs_delayed_item *item)
 550 {
 551         struct btrfs_block_rsv *src_rsv;
 552         struct btrfs_block_rsv *dst_rsv;
 553         struct btrfs_fs_info *fs_info = root->fs_info;
 554         u64 num_bytes;
 555         int ret;
 556
 557         if (!trans->bytes_reserved)
 558                 return 0;
 559
 560         src_rsv = trans->block_rsv;
 561         dst_rsv = &fs_info->delayed_block_rsv;
 562
 563         num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
 564
 565         /*
 566          * Here we migrate space rsv from transaction rsv, since have already
 567          * reserved space when starting a transaction.  So no need to reserve
 568          * qgroup space here.
 569          */
 570         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, true);
 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_root *root,
 582                                                 struct btrfs_delayed_item *item)
 583 {
 584         struct btrfs_block_rsv *rsv;
 585         struct btrfs_fs_info *fs_info = root->fs_info;
 586
 587         if (!item->bytes_reserved)
 588                 return;
 589
 590         rsv = &fs_info->delayed_block_rsv;
 591         /*
 592          * Check btrfs_delayed_item_reserve_metadata() to see why we don't need
 593          * to release/reserve qgroup space.
 594          */
 595         trace_btrfs_space_reservation(fs_info, "delayed_item",
 596                                       item->key.objectid, item->bytes_reserved,
 597                                       0);
 598         btrfs_block_rsv_release(fs_info, rsv,
 599                                 item->bytes_reserved);
 600 }
 601
 602 static int btrfs_delayed_inode_reserve_metadata(
 603                                         struct btrfs_trans_handle *trans,
 604                                         struct btrfs_root *root,
 605                                         struct btrfs_inode *inode,
 606                                         struct btrfs_delayed_node *node)
 607 {
 608         struct btrfs_fs_info *fs_info = root->fs_info;
 609         struct btrfs_block_rsv *src_rsv;
 610         struct btrfs_block_rsv *dst_rsv;
 611         u64 num_bytes;
 612         int ret;
 613
 614         src_rsv = trans->block_rsv;
 615         dst_rsv = &fs_info->delayed_block_rsv;
 616
 617         num_bytes = btrfs_calc_metadata_size(fs_info, 1);
 618
 619         /*
 620          * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 621          * which doesn't reserve space for speed.  This is a problem since we
 622          * still need to reserve space for this update, so try to reserve the
 623          * space.
 624          *
 625          * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
 626          * we always reserve enough to update the inode item.
 627          */
 628         if (!src_rsv || (!trans->bytes_reserved &&
 629                          src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
 630                 ret = btrfs_qgroup_reserve_meta_prealloc(root,
 631                                 fs_info->nodesize, true);
 632                 if (ret < 0)
 633                         return ret;
 634                 ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 635                                           BTRFS_RESERVE_NO_FLUSH);
 636                 /*
 637                  * Since we're under a transaction reserve_metadata_bytes could
 638                  * try to commit the transaction which will make it return
 639                  * EAGAIN to make us stop the transaction we have, so return
 640                  * ENOSPC instead so that btrfs_dirty_inode knows what to do.
 641                  */
 642                 if (ret == -EAGAIN) {
 643                         ret = -ENOSPC;
 644                         btrfs_qgroup_free_meta_prealloc(root, num_bytes);
 645                 }
 646                 if (!ret) {
 647                         node->bytes_reserved = num_bytes;
 648                         trace_btrfs_space_reservation(fs_info,
 649                                                       "delayed_inode",
 650                                                       btrfs_ino(inode),
 651                                                       num_bytes, 1);
 652                 } else {
 653                         btrfs_qgroup_free_meta_prealloc(root, fs_info->nodesize);
 654                 }
 655                 return ret;
 656         }
 657
 658         ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, true);
 659         if (!ret) {
 660                 trace_btrfs_space_reservation(fs_info, "delayed_inode",
 661                                               btrfs_ino(inode), num_bytes, 1);
 662                 node->bytes_reserved = num_bytes;
 663         }
 664
 665         return ret;
 666 }
 667
 668 static void btrfs_delayed_inode_release_metadata(struct btrfs_fs_info *fs_info,
 669                                                 struct btrfs_delayed_node *node,
 670                                                 bool qgroup_free)
 671 {
 672         struct btrfs_block_rsv *rsv;
 673
 674         if (!node->bytes_reserved)
 675                 return;
 676
 677         rsv = &fs_info->delayed_block_rsv;
 678         trace_btrfs_space_reservation(fs_info, "delayed_inode",
 679                                       node->inode_id, node->bytes_reserved, 0);
 680         btrfs_block_rsv_release(fs_info, rsv,
 681                                 node->bytes_reserved);
 682         if (qgroup_free)
 683                 btrfs_qgroup_free_meta_prealloc(node->root,
 684                                 node->bytes_reserved);
 685         else
 686                 btrfs_qgroup_convert_reserved_meta(node->root,
 687                                 node->bytes_reserved);
 688         node->bytes_reserved = 0;
 689 }
 690
 691 /*
 692  * This helper will insert some continuous items into the same leaf according
 693  * to the free space of the leaf.
 694  */
 695 static int btrfs_batch_insert_items(struct btrfs_root *root,
 696                                     struct btrfs_path *path,
 697                                     struct btrfs_delayed_item *item)
 698 {
 699         struct btrfs_delayed_item *curr, *next;
 700         int free_space;
 701         int total_data_size = 0, total_size = 0;
 702         struct extent_buffer *leaf;
 703         char *data_ptr;
 704         struct btrfs_key *keys;
 705         u32 *data_size;
 706         struct list_head head;
 707         int slot;
 708         int nitems;
 709         int i;
 710         int ret = 0;
 711
 712         BUG_ON(!path->nodes[0]);
 713
 714         leaf = path->nodes[0];
 715         free_space = btrfs_leaf_free_space(leaf);
 716         INIT_LIST_HEAD(&head);
 717
 718         next = item;
 719         nitems = 0;
 720
 721         /*
 722          * count the number of the continuous items that we can insert in batch
 723          */
 724         while (total_size + next->data_len + sizeof(struct btrfs_item) <=
 725                free_space) {
 726                 total_data_size += next->data_len;
 727                 total_size += next->data_len + sizeof(struct btrfs_item);
 728                 list_add_tail(&next->tree_list, &head);
 729                 nitems++;
 730
 731                 curr = next;
 732                 next = __btrfs_next_delayed_item(curr);
 733                 if (!next)
 734                         break;
 735
 736                 if (!btrfs_is_continuous_delayed_item(curr, next))
 737                         break;
 738         }
 739
 740         if (!nitems) {
 741                 ret = 0;
 742                 goto out;
 743         }
 744
 745         /*
 746          * we need allocate some memory space, but it might cause the task
 747          * to sleep, so we set all locked nodes in the path to blocking locks
 748          * first.
 749          */
 750         btrfs_set_path_blocking(path);
 751
 752         keys = kmalloc_array(nitems, sizeof(struct btrfs_key), GFP_NOFS);
 753         if (!keys) {
 754                 ret = -ENOMEM;
 755                 goto out;
 756         }
 757
 758         data_size = kmalloc_array(nitems, sizeof(u32), GFP_NOFS);
 759         if (!data_size) {
 760                 ret = -ENOMEM;
 761                 goto error;
 762         }
 763
 764         /* get keys of all the delayed items */
 765         i = 0;
 766         list_for_each_entry(next, &head, tree_list) {
 767                 keys[i] = next->key;
 768                 data_size[i] = next->data_len;
 769                 i++;
 770         }
 771
 772         /* insert the keys of the items */
 773         setup_items_for_insert(root, path, keys, data_size,
 774                                total_data_size, total_size, nitems);
 775
 776         /* insert the dir index items */
 777         slot = path->slots[0];
 778         list_for_each_entry_safe(curr, next, &head, tree_list) {
 779                 data_ptr = btrfs_item_ptr(leaf, slot, char);
 780                 write_extent_buffer(leaf, &curr->data,
 781                                     (unsigned long)data_ptr,
 782                                     curr->data_len);
 783                 slot++;
 784
 785                 btrfs_delayed_item_release_metadata(root, curr);
 786
 787                 list_del(&curr->tree_list);
 788                 btrfs_release_delayed_item(curr);
 789         }
 790
 791 error:
 792         kfree(data_size);
 793         kfree(keys);
 794 out:
 795         return ret;
 796 }
 797
 798 /*
 799  * This helper can just do simple insertion that needn't extend item for new
 800  * data, such as directory name index insertion, inode insertion.
 801  */
 802 static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 803                                      struct btrfs_root *root,
 804                                      struct btrfs_path *path,
 805                                      struct btrfs_delayed_item *delayed_item)
 806 {
 807         struct extent_buffer *leaf;
 808         char *ptr;
 809         int ret;
 810
 811         ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
 812                                       delayed_item->data_len);
 813         if (ret < 0 && ret != -EEXIST)
 814                 return ret;
 815
 816         leaf = path->nodes[0];
 817
 818         ptr = btrfs_item_ptr(leaf, path->slots[0], char);
 819
 820         write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
 821                             delayed_item->data_len);
 822         btrfs_mark_buffer_dirty(leaf);
 823
 824         btrfs_delayed_item_release_metadata(root, delayed_item);
 825         return 0;
 826 }
 827
 828 /*
 829  * we insert an item first, then if there are some continuous items, we try
 830  * to insert those items into the same leaf.
 831  */
 832 static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 833                                       struct btrfs_path *path,
 834                                       struct btrfs_root *root,
 835                                       struct btrfs_delayed_node *node)
 836 {
 837         struct btrfs_delayed_item *curr, *prev;
 838         int ret = 0;
 839
 840 do_again:
 841         mutex_lock(&node->mutex);
 842         curr = __btrfs_first_delayed_insertion_item(node);
 843         if (!curr)
 844                 goto insert_end;
 845
 846         ret = btrfs_insert_delayed_item(trans, root, path, curr);
 847         if (ret < 0) {
 848                 btrfs_release_path(path);
 849                 goto insert_end;
 850         }
 851
 852         prev = curr;
 853         curr = __btrfs_next_delayed_item(prev);
 854         if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
 855                 /* insert the continuous items into the same leaf */
 856                 path->slots[0]++;
 857                 btrfs_batch_insert_items(root, path, curr);
 858         }
 859         btrfs_release_delayed_item(prev);
 860         btrfs_mark_buffer_dirty(path->nodes[0]);
 861
 862         btrfs_release_path(path);
 863         mutex_unlock(&node->mutex);
 864         goto do_again;
 865
 866 insert_end:
 867         mutex_unlock(&node->mutex);
 868         return ret;
 869 }
 870
 871 static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
 872                                     struct btrfs_root *root,
 873                                     struct btrfs_path *path,
 874                                     struct btrfs_delayed_item *item)
 875 {
 876         struct btrfs_delayed_item *curr, *next;
 877         struct extent_buffer *leaf;
 878         struct btrfs_key key;
 879         struct list_head head;
 880         int nitems, i, last_item;
 881         int ret = 0;
 882
 883         BUG_ON(!path->nodes[0]);
 884
 885         leaf = path->nodes[0];
 886
 887         i = path->slots[0];
 888         last_item = btrfs_header_nritems(leaf) - 1;
 889         if (i > last_item)
 890                 return -ENOENT; /* FIXME: Is errno suitable? */
 891
 892         next = item;
 893         INIT_LIST_HEAD(&head);
 894         btrfs_item_key_to_cpu(leaf, &key, i);
 895         nitems = 0;
 896         /*
 897          * count the number of the dir index items that we can delete in batch
 898          */
 899         while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
 900                 list_add_tail(&next->tree_list, &head);
 901                 nitems++;
 902
 903                 curr = next;
 904                 next = __btrfs_next_delayed_item(curr);
 905                 if (!next)
 906                         break;
 907
 908                 if (!btrfs_is_continuous_delayed_item(curr, next))
 909                         break;
 910
 911                 i++;
 912                 if (i > last_item)
 913                         break;
 914                 btrfs_item_key_to_cpu(leaf, &key, i);
 915         }
 916
 917         if (!nitems)
 918                 return 0;
 919
 920         ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 921         if (ret)
 922                 goto out;
 923
 924         list_for_each_entry_safe(curr, next, &head, tree_list) {
 925                 btrfs_delayed_item_release_metadata(root, curr);
 926                 list_del(&curr->tree_list);
 927                 btrfs_release_delayed_item(curr);
 928         }
 929
 930 out:
 931         return ret;
 932 }
 933
 934 static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 935                                       struct btrfs_path *path,
 936                                       struct btrfs_root *root,
 937                                       struct btrfs_delayed_node *node)
 938 {
 939         struct btrfs_delayed_item *curr, *prev;
 940         int ret = 0;
 941
 942 do_again:
 943         mutex_lock(&node->mutex);
 944         curr = __btrfs_first_delayed_deletion_item(node);
 945         if (!curr)
 946                 goto delete_fail;
 947
 948         ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
 949         if (ret < 0)
 950                 goto delete_fail;
 951         else if (ret > 0) {
 952                 /*
 953                  * can't find the item which the node points to, so this node
 954                  * is invalid, just drop it.
 955                  */
 956                 prev = curr;
 957                 curr = __btrfs_next_delayed_item(prev);
 958                 btrfs_release_delayed_item(prev);
 959                 ret = 0;
 960                 btrfs_release_path(path);
 961                 if (curr) {
 962                         mutex_unlock(&node->mutex);
 963                         goto do_again;
 964                 } else
 965                         goto delete_fail;
 966         }
 967
 968         btrfs_batch_delete_items(trans, root, path, curr);
 969         btrfs_release_path(path);
 970         mutex_unlock(&node->mutex);
 971         goto do_again;
 972
 973 delete_fail:
 974         btrfs_release_path(path);
 975         mutex_unlock(&node->mutex);
 976         return ret;
 977 }
 978
 979 static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
 980 {
 981         struct btrfs_delayed_root *delayed_root;
 982
 983         if (delayed_node &&
 984             test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
 985                 BUG_ON(!delayed_node->root);
 986                 clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
 987                 delayed_node->count--;
 988
 989                 delayed_root = delayed_node->root->fs_info->delayed_root;
 990                 finish_one_item(delayed_root);
 991         }
 992 }
 993
 994 static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
 995 {
 996         struct btrfs_delayed_root *delayed_root;
 997
 998         ASSERT(delayed_node->root);
 999         clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1000         delayed_node->count--;
1001
1002         delayed_root = delayed_node->root->fs_info->delayed_root;
1003         finish_one_item(delayed_root);
1004 }
1005
1006 static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1007                                         struct btrfs_root *root,
1008                                         struct btrfs_path *path,
1009                                         struct btrfs_delayed_node *node)
1010 {
1011         struct btrfs_fs_info *fs_info = root->fs_info;
1012         struct btrfs_key key;
1013         struct btrfs_inode_item *inode_item;
1014         struct extent_buffer *leaf;
1015         int mod;
1016         int ret;
1017
1018         key.objectid = node->inode_id;
1019         key.type = BTRFS_INODE_ITEM_KEY;
1020         key.offset = 0;
1021
1022         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1023                 mod = -1;
1024         else
1025                 mod = 1;
1026
1027         ret = btrfs_lookup_inode(trans, root, path, &key, mod);
1028         if (ret > 0) {
1029                 btrfs_release_path(path);
1030                 return -ENOENT;
1031         } else if (ret < 0) {
1032                 return ret;
1033         }
1034
1035         leaf = path->nodes[0];
1036         inode_item = btrfs_item_ptr(leaf, path->slots[0],
1037                                     struct btrfs_inode_item);
1038         write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1039                             sizeof(struct btrfs_inode_item));
1040         btrfs_mark_buffer_dirty(leaf);
1041
1042         if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1043                 goto no_iref;
1044
1045         path->slots[0]++;
1046         if (path->slots[0] >= btrfs_header_nritems(leaf))
1047                 goto search;
1048 again:
1049         btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1050         if (key.objectid != node->inode_id)
1051                 goto out;
1052
1053         if (key.type != BTRFS_INODE_REF_KEY &&
1054             key.type != BTRFS_INODE_EXTREF_KEY)
1055                 goto out;
1056
1057         /*
1058          * Delayed iref deletion is for the inode who has only one link,
1059          * so there is only one iref. The case that several irefs are
1060          * in the same item doesn't exist.
1061          */
1062         btrfs_del_item(trans, root, path);
1063 out:
1064         btrfs_release_delayed_iref(node);
1065 no_iref:
1066         btrfs_release_path(path);
1067 err_out:
1068         btrfs_delayed_inode_release_metadata(fs_info, node, (ret < 0));
1069         btrfs_release_delayed_inode(node);
1070
1071         return ret;
1072
1073 search:
1074         btrfs_release_path(path);
1075
1076         key.type = BTRFS_INODE_EXTREF_KEY;
1077         key.offset = -1;
1078         ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1079         if (ret < 0)
1080                 goto err_out;
1081         ASSERT(ret);
1082
1083         ret = 0;
1084         leaf = path->nodes[0];
1085         path->slots[0]--;
1086         goto again;
1087 }
1088
1089 static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1090                                              struct btrfs_root *root,
1091                                              struct btrfs_path *path,
1092                                              struct btrfs_delayed_node *node)
1093 {
1094         int ret;
1095
1096         mutex_lock(&node->mutex);
1097         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
1098                 mutex_unlock(&node->mutex);
1099                 return 0;
1100         }
1101
1102         ret = __btrfs_update_delayed_inode(trans, root, path, node);
1103         mutex_unlock(&node->mutex);
1104         return ret;
1105 }
1106
1107 static inline int
1108 __btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1109                                    struct btrfs_path *path,
1110                                    struct btrfs_delayed_node *node)
1111 {
1112         int ret;
1113
1114         ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1115         if (ret)
1116                 return ret;
1117
1118         ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1119         if (ret)
1120                 return ret;
1121
1122         ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1123         return ret;
1124 }
1125
1126 /*
1127  * Called when committing the transaction.
1128  * Returns 0 on success.
1129  * Returns < 0 on error and returns with an aborted transaction with any
1130  * outstanding delayed items cleaned up.
1131  */
1132 static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans, int nr)
1133 {
1134         struct btrfs_fs_info *fs_info = trans->fs_info;
1135         struct btrfs_delayed_root *delayed_root;
1136         struct btrfs_delayed_node *curr_node, *prev_node;
1137         struct btrfs_path *path;
1138         struct btrfs_block_rsv *block_rsv;
1139         int ret = 0;
1140         bool count = (nr > 0);
1141
1142         if (trans->aborted)
1143                 return -EIO;
1144
1145         path = btrfs_alloc_path();
1146         if (!path)
1147                 return -ENOMEM;
1148         path->leave_spinning = 1;
1149
1150         block_rsv = trans->block_rsv;
1151         trans->block_rsv = &fs_info->delayed_block_rsv;
1152
1153         delayed_root = fs_info->delayed_root;
1154
1155         curr_node = btrfs_first_delayed_node(delayed_root);
1156         while (curr_node && (!count || (count && nr--))) {
1157                 ret = __btrfs_commit_inode_delayed_items(trans, path,
1158                                                          curr_node);
1159                 if (ret) {
1160                         btrfs_release_delayed_node(curr_node);
1161                         curr_node = NULL;
1162                         btrfs_abort_transaction(trans, ret);
1163                         break;
1164                 }
1165
1166                 prev_node = curr_node;
1167                 curr_node = btrfs_next_delayed_node(curr_node);
1168                 btrfs_release_delayed_node(prev_node);
1169         }
1170
1171         if (curr_node)
1172                 btrfs_release_delayed_node(curr_node);
1173         btrfs_free_path(path);
1174         trans->block_rsv = block_rsv;
1175
1176         return ret;
1177 }
1178
1179 int btrfs_run_delayed_items(struct btrfs_trans_handle *trans)
1180 {
1181         return __btrfs_run_delayed_items(trans, -1);
1182 }
1183
1184 int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans, int nr)
1185 {
1186         return __btrfs_run_delayed_items(trans, nr);
1187 }
1188
1189 int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1190                                      struct btrfs_inode *inode)
1191 {
1192         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1193         struct btrfs_path *path;
1194         struct btrfs_block_rsv *block_rsv;
1195         int ret;
1196
1197         if (!delayed_node)
1198                 return 0;
1199
1200         mutex_lock(&delayed_node->mutex);
1201         if (!delayed_node->count) {
1202                 mutex_unlock(&delayed_node->mutex);
1203                 btrfs_release_delayed_node(delayed_node);
1204                 return 0;
1205         }
1206         mutex_unlock(&delayed_node->mutex);
1207
1208         path = btrfs_alloc_path();
1209         if (!path) {
1210                 btrfs_release_delayed_node(delayed_node);
1211                 return -ENOMEM;
1212         }
1213         path->leave_spinning = 1;
1214
1215         block_rsv = trans->block_rsv;
1216         trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1217
1218         ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1219
1220         btrfs_release_delayed_node(delayed_node);
1221         btrfs_free_path(path);
1222         trans->block_rsv = block_rsv;
1223
1224         return ret;
1225 }
1226
1227 int btrfs_commit_inode_delayed_inode(struct btrfs_inode *inode)
1228 {
1229         struct btrfs_fs_info *fs_info = inode->root->fs_info;
1230         struct btrfs_trans_handle *trans;
1231         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1232         struct btrfs_path *path;
1233         struct btrfs_block_rsv *block_rsv;
1234         int ret;
1235
1236         if (!delayed_node)
1237                 return 0;
1238
1239         mutex_lock(&delayed_node->mutex);
1240         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1241                 mutex_unlock(&delayed_node->mutex);
1242                 btrfs_release_delayed_node(delayed_node);
1243                 return 0;
1244         }
1245         mutex_unlock(&delayed_node->mutex);
1246
1247         trans = btrfs_join_transaction(delayed_node->root);
1248         if (IS_ERR(trans)) {
1249                 ret = PTR_ERR(trans);
1250                 goto out;
1251         }
1252
1253         path = btrfs_alloc_path();
1254         if (!path) {
1255                 ret = -ENOMEM;
1256                 goto trans_out;
1257         }
1258         path->leave_spinning = 1;
1259
1260         block_rsv = trans->block_rsv;
1261         trans->block_rsv = &fs_info->delayed_block_rsv;
1262
1263         mutex_lock(&delayed_node->mutex);
1264         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
1265                 ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1266                                                    path, delayed_node);
1267         else
1268                 ret = 0;
1269         mutex_unlock(&delayed_node->mutex);
1270
1271         btrfs_free_path(path);
1272         trans->block_rsv = block_rsv;
1273 trans_out:
1274         btrfs_end_transaction(trans);
1275         btrfs_btree_balance_dirty(fs_info);
1276 out:
1277         btrfs_release_delayed_node(delayed_node);
1278
1279         return ret;
1280 }
1281
1282 void btrfs_remove_delayed_node(struct btrfs_inode *inode)
1283 {
1284         struct btrfs_delayed_node *delayed_node;
1285
1286         delayed_node = READ_ONCE(inode->delayed_node);
1287         if (!delayed_node)
1288                 return;
1289
1290         inode->delayed_node = NULL;
1291         btrfs_release_delayed_node(delayed_node);
1292 }
1293
1294 struct btrfs_async_delayed_work {
1295         struct btrfs_delayed_root *delayed_root;
1296         int nr;
1297         struct btrfs_work work;
1298 };
1299
1300 static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1301 {
1302         struct btrfs_async_delayed_work *async_work;
1303         struct btrfs_delayed_root *delayed_root;
1304         struct btrfs_trans_handle *trans;
1305         struct btrfs_path *path;
1306         struct btrfs_delayed_node *delayed_node = NULL;
1307         struct btrfs_root *root;
1308         struct btrfs_block_rsv *block_rsv;
1309         int total_done = 0;
1310
1311         async_work = container_of(work, struct btrfs_async_delayed_work, work);
1312         delayed_root = async_work->delayed_root;
1313
1314         path = btrfs_alloc_path();
1315         if (!path)
1316                 goto out;
1317
1318         do {
1319                 if (atomic_read(&delayed_root->items) <
1320                     BTRFS_DELAYED_BACKGROUND / 2)
1321                         break;
1322
1323                 delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1324                 if (!delayed_node)
1325                         break;
1326
1327                 path->leave_spinning = 1;
1328                 root = delayed_node->root;
1329
1330                 trans = btrfs_join_transaction(root);
1331                 if (IS_ERR(trans)) {
1332                         btrfs_release_path(path);
1333                         btrfs_release_prepared_delayed_node(delayed_node);
1334                         total_done++;
1335                         continue;
1336                 }
1337
1338                 block_rsv = trans->block_rsv;
1339                 trans->block_rsv = &root->fs_info->delayed_block_rsv;
1340
1341                 __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1342
1343                 trans->block_rsv = block_rsv;
1344                 btrfs_end_transaction(trans);
1345                 btrfs_btree_balance_dirty_nodelay(root->fs_info);
1346
1347                 btrfs_release_path(path);
1348                 btrfs_release_prepared_delayed_node(delayed_node);
1349                 total_done++;
1350
1351         } while ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK)
1352                  || total_done < async_work->nr);
1353
1354         btrfs_free_path(path);
1355 out:
1356         wake_up(&delayed_root->wait);
1357         kfree(async_work);
1358 }
1359
1360
1361 static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1362                                      struct btrfs_fs_info *fs_info, int nr)
1363 {
1364         struct btrfs_async_delayed_work *async_work;
1365
1366         async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
1367         if (!async_work)
1368                 return -ENOMEM;
1369
1370         async_work->delayed_root = delayed_root;
1371         btrfs_init_work(&async_work->work, btrfs_async_run_delayed_root, NULL,
1372                         NULL);
1373         async_work->nr = nr;
1374
1375         btrfs_queue_work(fs_info->delayed_workers, &async_work->work);
1376         return 0;
1377 }
1378
1379 void btrfs_assert_delayed_root_empty(struct btrfs_fs_info *fs_info)
1380 {
1381         WARN_ON(btrfs_first_delayed_node(fs_info->delayed_root));
1382 }
1383
1384 static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
1385 {
1386         int val = atomic_read(&delayed_root->items_seq);
1387
1388         if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
1389                 return 1;
1390
1391         if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1392                 return 1;
1393
1394         return 0;
1395 }
1396
1397 void btrfs_balance_delayed_items(struct btrfs_fs_info *fs_info)
1398 {
1399         struct btrfs_delayed_root *delayed_root = fs_info->delayed_root;
1400
1401         if ((atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND) ||
1402                 btrfs_workqueue_normal_congested(fs_info->delayed_workers))
1403                 return;
1404
1405         if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1406                 int seq;
1407                 int ret;
1408
1409                 seq = atomic_read(&delayed_root->items_seq);
1410
1411                 ret = btrfs_wq_run_delayed_node(delayed_root, fs_info, 0);
1412                 if (ret)
1413                         return;
1414
1415                 wait_event_interruptible(delayed_root->wait,
1416                                          could_end_wait(delayed_root, seq));
1417                 return;
1418         }
1419
1420         btrfs_wq_run_delayed_node(delayed_root, fs_info, BTRFS_DELAYED_BATCH);
1421 }
1422
1423 /* Will return 0 or -ENOMEM */
1424 int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1425                                    const char *name, int name_len,
1426                                    struct btrfs_inode *dir,
1427                                    struct btrfs_disk_key *disk_key, u8 type,
1428                                    u64 index)
1429 {
1430         struct btrfs_delayed_node *delayed_node;
1431         struct btrfs_delayed_item *delayed_item;
1432         struct btrfs_dir_item *dir_item;
1433         int ret;
1434
1435         delayed_node = btrfs_get_or_create_delayed_node(dir);
1436         if (IS_ERR(delayed_node))
1437                 return PTR_ERR(delayed_node);
1438
1439         delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
1440         if (!delayed_item) {
1441                 ret = -ENOMEM;
1442                 goto release_node;
1443         }
1444
1445         delayed_item->key.objectid = btrfs_ino(dir);
1446         delayed_item->key.type = BTRFS_DIR_INDEX_KEY;
1447         delayed_item->key.offset = index;
1448
1449         dir_item = (struct btrfs_dir_item *)delayed_item->data;
1450         dir_item->location = *disk_key;
1451         btrfs_set_stack_dir_transid(dir_item, trans->transid);
1452         btrfs_set_stack_dir_data_len(dir_item, 0);
1453         btrfs_set_stack_dir_name_len(dir_item, name_len);
1454         btrfs_set_stack_dir_type(dir_item, type);
1455         memcpy((char *)(dir_item + 1), name, name_len);
1456
1457         ret = btrfs_delayed_item_reserve_metadata(trans, dir->root, delayed_item);
1458         /*
1459          * we have reserved enough space when we start a new transaction,
1460          * so reserving metadata failure is impossible
1461          */
1462         BUG_ON(ret);
1463
1464         mutex_lock(&delayed_node->mutex);
1465         ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1466         if (unlikely(ret)) {
1467                 btrfs_err(trans->fs_info,
1468                           "err add delayed dir index item(name: %.*s) into the insertion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1469                           name_len, name, delayed_node->root->root_key.objectid,
1470                           delayed_node->inode_id, ret);
1471                 BUG();
1472         }
1473         mutex_unlock(&delayed_node->mutex);
1474
1475 release_node:
1476         btrfs_release_delayed_node(delayed_node);
1477         return ret;
1478 }
1479
1480 static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info,
1481                                                struct btrfs_delayed_node *node,
1482                                                struct btrfs_key *key)
1483 {
1484         struct btrfs_delayed_item *item;
1485
1486         mutex_lock(&node->mutex);
1487         item = __btrfs_lookup_delayed_insertion_item(node, key);
1488         if (!item) {
1489                 mutex_unlock(&node->mutex);
1490                 return 1;
1491         }
1492
1493         btrfs_delayed_item_release_metadata(node->root, item);
1494         btrfs_release_delayed_item(item);
1495         mutex_unlock(&node->mutex);
1496         return 0;
1497 }
1498
1499 int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1500                                    struct btrfs_inode *dir, u64 index)
1501 {
1502         struct btrfs_delayed_node *node;
1503         struct btrfs_delayed_item *item;
1504         struct btrfs_key item_key;
1505         int ret;
1506
1507         node = btrfs_get_or_create_delayed_node(dir);
1508         if (IS_ERR(node))
1509                 return PTR_ERR(node);
1510
1511         item_key.objectid = btrfs_ino(dir);
1512         item_key.type = BTRFS_DIR_INDEX_KEY;
1513         item_key.offset = index;
1514
1515         ret = btrfs_delete_delayed_insertion_item(trans->fs_info, node,
1516                                                   &item_key);
1517         if (!ret)
1518                 goto end;
1519
1520         item = btrfs_alloc_delayed_item(0);
1521         if (!item) {
1522                 ret = -ENOMEM;
1523                 goto end;
1524         }
1525
1526         item->key = item_key;
1527
1528         ret = btrfs_delayed_item_reserve_metadata(trans, dir->root, item);
1529         /*
1530          * we have reserved enough space when we start a new transaction,
1531          * so reserving metadata failure is impossible.
1532          */
1533         if (ret < 0) {
1534                 btrfs_err(trans->fs_info,
1535 "metadata reservation failed for delayed dir item deltiona, should have been reserved");
1536                 btrfs_release_delayed_item(item);
1537                 goto end;
1538         }
1539
1540         mutex_lock(&node->mutex);
1541         ret = __btrfs_add_delayed_deletion_item(node, item);
1542         if (unlikely(ret)) {
1543                 btrfs_err(trans->fs_info,
1544                           "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1545                           index, node->root->root_key.objectid,
1546                           node->inode_id, ret);
1547                 btrfs_delayed_item_release_metadata(dir->root, item);
1548                 btrfs_release_delayed_item(item);
1549         }
1550         mutex_unlock(&node->mutex);
1551 end:
1552         btrfs_release_delayed_node(node);
1553         return ret;
1554 }
1555
1556 int btrfs_inode_delayed_dir_index_count(struct btrfs_inode *inode)
1557 {
1558         struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1559
1560         if (!delayed_node)
1561                 return -ENOENT;
1562
1563         /*
1564          * Since we have held i_mutex of this directory, it is impossible that
1565          * a new directory index is added into the delayed node and index_cnt
1566          * is updated now. So we needn't lock the delayed node.
1567          */
1568         if (!delayed_node->index_cnt) {
1569                 btrfs_release_delayed_node(delayed_node);
1570                 return -EINVAL;
1571         }
1572
1573         inode->index_cnt = delayed_node->index_cnt;
1574         btrfs_release_delayed_node(delayed_node);
1575         return 0;
1576 }
1577
1578 bool btrfs_readdir_get_delayed_items(struct inode *inode,
1579                                      struct list_head *ins_list,
1580                                      struct list_head *del_list)
1581 {
1582         struct btrfs_delayed_node *delayed_node;
1583         struct btrfs_delayed_item *item;
1584
1585         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1586         if (!delayed_node)
1587                 return false;
1588
1589         /*
1590          * We can only do one readdir with delayed items at a time because of
1591          * item->readdir_list.
1592          */
1593         inode_unlock_shared(inode);
1594         inode_lock(inode);
1595
1596         mutex_lock(&delayed_node->mutex);
1597         item = __btrfs_first_delayed_insertion_item(delayed_node);
1598         while (item) {
1599                 refcount_inc(&item->refs);
1600                 list_add_tail(&item->readdir_list, ins_list);
1601                 item = __btrfs_next_delayed_item(item);
1602         }
1603
1604         item = __btrfs_first_delayed_deletion_item(delayed_node);
1605         while (item) {
1606                 refcount_inc(&item->refs);
1607                 list_add_tail(&item->readdir_list, del_list);
1608                 item = __btrfs_next_delayed_item(item);
1609         }
1610         mutex_unlock(&delayed_node->mutex);
1611         /*
1612          * This delayed node is still cached in the btrfs inode, so refs
1613          * must be > 1 now, and we needn't check it is going to be freed
1614          * or not.
1615          *
1616          * Besides that, this function is used to read dir, we do not
1617          * insert/delete delayed items in this period. So we also needn't
1618          * requeue or dequeue this delayed node.
1619          */
1620         refcount_dec(&delayed_node->refs);
1621
1622         return true;
1623 }
1624
1625 void btrfs_readdir_put_delayed_items(struct inode *inode,
1626                                      struct list_head *ins_list,
1627                                      struct list_head *del_list)
1628 {
1629         struct btrfs_delayed_item *curr, *next;
1630
1631         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1632                 list_del(&curr->readdir_list);
1633                 if (refcount_dec_and_test(&curr->refs))
1634                         kfree(curr);
1635         }
1636
1637         list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1638                 list_del(&curr->readdir_list);
1639                 if (refcount_dec_and_test(&curr->refs))
1640                         kfree(curr);
1641         }
1642
1643         /*
1644          * The VFS is going to do up_read(), so we need to downgrade back to a
1645          * read lock.
1646          */
1647         downgrade_write(&inode->i_rwsem);
1648 }
1649
1650 int btrfs_should_delete_dir_index(struct list_head *del_list,
1651                                   u64 index)
1652 {
1653         struct btrfs_delayed_item *curr;
1654         int ret = 0;
1655
1656         list_for_each_entry(curr, del_list, readdir_list) {
1657                 if (curr->key.offset > index)
1658                         break;
1659                 if (curr->key.offset == index) {
1660                         ret = 1;
1661                         break;
1662                 }
1663         }
1664         return ret;
1665 }
1666
1667 /*
1668  * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1669  *
1670  */
1671 int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
1672                                     struct list_head *ins_list)
1673 {
1674         struct btrfs_dir_item *di;
1675         struct btrfs_delayed_item *curr, *next;
1676         struct btrfs_key location;
1677         char *name;
1678         int name_len;
1679         int over = 0;
1680         unsigned char d_type;
1681
1682         if (list_empty(ins_list))
1683                 return 0;
1684
1685         /*
1686          * Changing the data of the delayed item is impossible. So
1687          * we needn't lock them. And we have held i_mutex of the
1688          * directory, nobody can delete any directory indexes now.
1689          */
1690         list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1691                 list_del(&curr->readdir_list);
1692
1693                 if (curr->key.offset < ctx->pos) {
1694                         if (refcount_dec_and_test(&curr->refs))
1695                                 kfree(curr);
1696                         continue;
1697                 }
1698
1699                 ctx->pos = curr->key.offset;
1700
1701                 di = (struct btrfs_dir_item *)curr->data;
1702                 name = (char *)(di + 1);
1703                 name_len = btrfs_stack_dir_name_len(di);
1704
1705                 d_type = fs_ftype_to_dtype(di->type);
1706                 btrfs_disk_key_to_cpu(&location, &di->location);
1707
1708                 over = !dir_emit(ctx, name, name_len,
1709                                location.objectid, d_type);
1710
1711                 if (refcount_dec_and_test(&curr->refs))
1712                         kfree(curr);
1713
1714                 if (over)
1715                         return 1;
1716                 ctx->pos++;
1717         }
1718         return 0;
1719 }
1720
1721 static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1722                                   struct btrfs_inode_item *inode_item,
1723                                   struct inode *inode)
1724 {
1725         btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1726         btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1727         btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1728         btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1729         btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1730         btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1731         btrfs_set_stack_inode_generation(inode_item,
1732                                          BTRFS_I(inode)->generation);
1733         btrfs_set_stack_inode_sequence(inode_item,
1734                                        inode_peek_iversion(inode));
1735         btrfs_set_stack_inode_transid(inode_item, trans->transid);
1736         btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1737         btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
1738         btrfs_set_stack_inode_block_group(inode_item, 0);
1739
1740         btrfs_set_stack_timespec_sec(&inode_item->atime,
1741                                      inode->i_atime.tv_sec);
1742         btrfs_set_stack_timespec_nsec(&inode_item->atime,
1743                                       inode->i_atime.tv_nsec);
1744
1745         btrfs_set_stack_timespec_sec(&inode_item->mtime,
1746                                      inode->i_mtime.tv_sec);
1747         btrfs_set_stack_timespec_nsec(&inode_item->mtime,
1748                                       inode->i_mtime.tv_nsec);
1749
1750         btrfs_set_stack_timespec_sec(&inode_item->ctime,
1751                                      inode->i_ctime.tv_sec);
1752         btrfs_set_stack_timespec_nsec(&inode_item->ctime,
1753                                       inode->i_ctime.tv_nsec);
1754
1755         btrfs_set_stack_timespec_sec(&inode_item->otime,
1756                                      BTRFS_I(inode)->i_otime.tv_sec);
1757         btrfs_set_stack_timespec_nsec(&inode_item->otime,
1758                                      BTRFS_I(inode)->i_otime.tv_nsec);
1759 }
1760
1761 int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1762 {
1763         struct btrfs_delayed_node *delayed_node;
1764         struct btrfs_inode_item *inode_item;
1765
1766         delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1767         if (!delayed_node)
1768                 return -ENOENT;
1769
1770         mutex_lock(&delayed_node->mutex);
1771         if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1772                 mutex_unlock(&delayed_node->mutex);
1773                 btrfs_release_delayed_node(delayed_node);
1774                 return -ENOENT;
1775         }
1776
1777         inode_item = &delayed_node->inode_item;
1778
1779         i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1780         i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1781         btrfs_i_size_write(BTRFS_I(inode), btrfs_stack_inode_size(inode_item));
1782         inode->i_mode = btrfs_stack_inode_mode(inode_item);
1783         set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1784         inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1785         BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1786         BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
1787
1788         inode_set_iversion_queried(inode,
1789                                    btrfs_stack_inode_sequence(inode_item));
1790         inode->i_rdev = 0;
1791         *rdev = btrfs_stack_inode_rdev(inode_item);
1792         BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
1793
1794         inode->i_atime.tv_sec = btrfs_stack_timespec_sec(&inode_item->atime);
1795         inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->atime);
1796
1797         inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(&inode_item->mtime);
1798         inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->mtime);
1799
1800         inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(&inode_item->ctime);
1801         inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->ctime);
1802
1803         BTRFS_I(inode)->i_otime.tv_sec =
1804                 btrfs_stack_timespec_sec(&inode_item->otime);
1805         BTRFS_I(inode)->i_otime.tv_nsec =
1806                 btrfs_stack_timespec_nsec(&inode_item->otime);
1807
1808         inode->i_generation = BTRFS_I(inode)->generation;
1809         BTRFS_I(inode)->index_cnt = (u64)-1;
1810
1811         mutex_unlock(&delayed_node->mutex);
1812         btrfs_release_delayed_node(delayed_node);
1813         return 0;
1814 }
1815
1816 int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1817                                struct btrfs_root *root, struct inode *inode)
1818 {
1819         struct btrfs_delayed_node *delayed_node;
1820         int ret = 0;
1821
1822         delayed_node = btrfs_get_or_create_delayed_node(BTRFS_I(inode));
1823         if (IS_ERR(delayed_node))
1824                 return PTR_ERR(delayed_node);
1825
1826         mutex_lock(&delayed_node->mutex);
1827         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1828                 fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1829                 goto release_node;
1830         }
1831
1832         ret = btrfs_delayed_inode_reserve_metadata(trans, root, BTRFS_I(inode),
1833                                                    delayed_node);
1834         if (ret)
1835                 goto release_node;
1836
1837         fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1838         set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1839         delayed_node->count++;
1840         atomic_inc(&root->fs_info->delayed_root->items);
1841 release_node:
1842         mutex_unlock(&delayed_node->mutex);
1843         btrfs_release_delayed_node(delayed_node);
1844         return ret;
1845 }
1846
1847 int btrfs_delayed_delete_inode_ref(struct btrfs_inode *inode)
1848 {
1849         struct btrfs_fs_info *fs_info = inode->root->fs_info;
1850         struct btrfs_delayed_node *delayed_node;
1851
1852         /*
1853          * we don't do delayed inode updates during log recovery because it
1854          * leads to enospc problems.  This means we also can't do
1855          * delayed inode refs
1856          */
1857         if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
1858                 return -EAGAIN;
1859
1860         delayed_node = btrfs_get_or_create_delayed_node(inode);
1861         if (IS_ERR(delayed_node))
1862                 return PTR_ERR(delayed_node);
1863
1864         /*
1865          * We don't reserve space for inode ref deletion is because:
1866          * - We ONLY do async inode ref deletion for the inode who has only
1867          *   one link(i_nlink == 1), it means there is only one inode ref.
1868          *   And in most case, the inode ref and the inode item are in the
1869          *   same leaf, and we will deal with them at the same time.
1870          *   Since we are sure we will reserve the space for the inode item,
1871          *   it is unnecessary to reserve space for inode ref deletion.
1872          * - If the inode ref and the inode item are not in the same leaf,
1873          *   We also needn't worry about enospc problem, because we reserve
1874          *   much more space for the inode update than it needs.
1875          * - At the worst, we can steal some space from the global reservation.
1876          *   It is very rare.
1877          */
1878         mutex_lock(&delayed_node->mutex);
1879         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1880                 goto release_node;
1881
1882         set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1883         delayed_node->count++;
1884         atomic_inc(&fs_info->delayed_root->items);
1885 release_node:
1886         mutex_unlock(&delayed_node->mutex);
1887         btrfs_release_delayed_node(delayed_node);
1888         return 0;
1889 }
1890
1891 static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1892 {
1893         struct btrfs_root *root = delayed_node->root;
1894         struct btrfs_fs_info *fs_info = root->fs_info;
1895         struct btrfs_delayed_item *curr_item, *prev_item;
1896
1897         mutex_lock(&delayed_node->mutex);
1898         curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1899         while (curr_item) {
1900                 btrfs_delayed_item_release_metadata(root, curr_item);
1901                 prev_item = curr_item;
1902                 curr_item = __btrfs_next_delayed_item(prev_item);
1903                 btrfs_release_delayed_item(prev_item);
1904         }
1905
1906         curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1907         while (curr_item) {
1908                 btrfs_delayed_item_release_metadata(root, curr_item);
1909                 prev_item = curr_item;
1910                 curr_item = __btrfs_next_delayed_item(prev_item);
1911                 btrfs_release_delayed_item(prev_item);
1912         }
1913
1914         if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1915                 btrfs_release_delayed_iref(delayed_node);
1916
1917         if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1918                 btrfs_delayed_inode_release_metadata(fs_info, delayed_node, false);
1919                 btrfs_release_delayed_inode(delayed_node);
1920         }
1921         mutex_unlock(&delayed_node->mutex);
1922 }
1923
1924 void btrfs_kill_delayed_inode_items(struct btrfs_inode *inode)
1925 {
1926         struct btrfs_delayed_node *delayed_node;
1927
1928         delayed_node = btrfs_get_delayed_node(inode);
1929         if (!delayed_node)
1930                 return;
1931
1932         __btrfs_kill_delayed_node(delayed_node);
1933         btrfs_release_delayed_node(delayed_node);
1934 }
1935
1936 void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1937 {
1938         u64 inode_id = 0;
1939         struct btrfs_delayed_node *delayed_nodes[8];
1940         int i, n;
1941
1942         while (1) {
1943                 spin_lock(&root->inode_lock);
1944                 n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1945                                            (void **)delayed_nodes, inode_id,
1946                                            ARRAY_SIZE(delayed_nodes));
1947                 if (!n) {
1948                         spin_unlock(&root->inode_lock);
1949                         break;
1950                 }
1951
1952                 inode_id = delayed_nodes[n - 1]->inode_id + 1;
1953                 for (i = 0; i < n; i++) {
1954                         /*
1955                          * Don't increase refs in case the node is dead and
1956                          * about to be removed from the tree in the loop below
1957                          */
1958                         if (!refcount_inc_not_zero(&delayed_nodes[i]->refs))
1959                                 delayed_nodes[i] = NULL;
1960                 }
1961                 spin_unlock(&root->inode_lock);
1962
1963                 for (i = 0; i < n; i++) {
1964                         if (!delayed_nodes[i])
1965                                 continue;
1966                         __btrfs_kill_delayed_node(delayed_nodes[i]);
1967                         btrfs_release_delayed_node(delayed_nodes[i]);
1968                 }
1969         }
1970 }
1971
1972 void btrfs_destroy_delayed_inodes(struct btrfs_fs_info *fs_info)
1973 {
1974         struct btrfs_delayed_node *curr_node, *prev_node;
1975
1976         curr_node = btrfs_first_delayed_node(fs_info->delayed_root);
1977         while (curr_node) {
1978                 __btrfs_kill_delayed_node(curr_node);
1979
1980                 prev_node = curr_node;
1981                 curr_node = btrfs_next_delayed_node(curr_node);
1982                 btrfs_release_delayed_node(prev_node);
1983         }
1984 }
1985