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v3.1
   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 "delayed-inode.h"
  22#include "disk-io.h"
  23#include "transaction.h"
 
  24
  25#define BTRFS_DELAYED_WRITEBACK		400
  26#define BTRFS_DELAYED_BACKGROUND	100
 
  27
  28static struct kmem_cache *delayed_node_cache;
  29
  30int __init btrfs_delayed_inode_init(void)
  31{
  32	delayed_node_cache = kmem_cache_create("delayed_node",
  33					sizeof(struct btrfs_delayed_node),
  34					0,
  35					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
  36					NULL);
  37	if (!delayed_node_cache)
  38		return -ENOMEM;
  39	return 0;
  40}
  41
  42void btrfs_delayed_inode_exit(void)
  43{
  44	if (delayed_node_cache)
  45		kmem_cache_destroy(delayed_node_cache);
  46}
  47
  48static inline void btrfs_init_delayed_node(
  49				struct btrfs_delayed_node *delayed_node,
  50				struct btrfs_root *root, u64 inode_id)
  51{
  52	delayed_node->root = root;
  53	delayed_node->inode_id = inode_id;
  54	atomic_set(&delayed_node->refs, 0);
  55	delayed_node->count = 0;
  56	delayed_node->in_list = 0;
  57	delayed_node->inode_dirty = 0;
  58	delayed_node->ins_root = RB_ROOT;
  59	delayed_node->del_root = RB_ROOT;
  60	mutex_init(&delayed_node->mutex);
  61	delayed_node->index_cnt = 0;
  62	INIT_LIST_HEAD(&delayed_node->n_list);
  63	INIT_LIST_HEAD(&delayed_node->p_list);
  64	delayed_node->bytes_reserved = 0;
 
  65}
  66
  67static inline int btrfs_is_continuous_delayed_item(
  68					struct btrfs_delayed_item *item1,
  69					struct btrfs_delayed_item *item2)
  70{
  71	if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
  72	    item1->key.objectid == item2->key.objectid &&
  73	    item1->key.type == item2->key.type &&
  74	    item1->key.offset + 1 == item2->key.offset)
  75		return 1;
  76	return 0;
  77}
  78
  79static inline struct btrfs_delayed_root *btrfs_get_delayed_root(
  80							struct btrfs_root *root)
  81{
  82	return root->fs_info->delayed_root;
  83}
  84
  85static struct btrfs_delayed_node *btrfs_get_delayed_node(struct inode *inode)
  86{
  87	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
  88	struct btrfs_root *root = btrfs_inode->root;
  89	u64 ino = btrfs_ino(inode);
  90	struct btrfs_delayed_node *node;
  91
  92	node = ACCESS_ONCE(btrfs_inode->delayed_node);
  93	if (node) {
  94		atomic_inc(&node->refs);
  95		return node;
  96	}
  97
  98	spin_lock(&root->inode_lock);
  99	node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
 100	if (node) {
 101		if (btrfs_inode->delayed_node) {
 102			atomic_inc(&node->refs);	/* can be accessed */
 103			BUG_ON(btrfs_inode->delayed_node != node);
 104			spin_unlock(&root->inode_lock);
 105			return node;
 106		}
 107		btrfs_inode->delayed_node = node;
 108		atomic_inc(&node->refs);	/* can be accessed */
 109		atomic_inc(&node->refs);	/* cached in the inode */
 110		spin_unlock(&root->inode_lock);
 111		return node;
 112	}
 113	spin_unlock(&root->inode_lock);
 114
 115	return NULL;
 116}
 117
 
 118static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 119							struct inode *inode)
 120{
 121	struct btrfs_delayed_node *node;
 122	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
 123	struct btrfs_root *root = btrfs_inode->root;
 124	u64 ino = btrfs_ino(inode);
 125	int ret;
 126
 127again:
 128	node = btrfs_get_delayed_node(inode);
 129	if (node)
 130		return node;
 131
 132	node = kmem_cache_alloc(delayed_node_cache, GFP_NOFS);
 133	if (!node)
 134		return ERR_PTR(-ENOMEM);
 135	btrfs_init_delayed_node(node, root, ino);
 136
 137	atomic_inc(&node->refs);	/* cached in the btrfs inode */
 138	atomic_inc(&node->refs);	/* can be accessed */
 139
 140	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
 141	if (ret) {
 142		kmem_cache_free(delayed_node_cache, node);
 143		return ERR_PTR(ret);
 144	}
 145
 146	spin_lock(&root->inode_lock);
 147	ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
 148	if (ret == -EEXIST) {
 149		kmem_cache_free(delayed_node_cache, node);
 150		spin_unlock(&root->inode_lock);
 151		radix_tree_preload_end();
 152		goto again;
 153	}
 154	btrfs_inode->delayed_node = node;
 155	spin_unlock(&root->inode_lock);
 156	radix_tree_preload_end();
 157
 158	return node;
 159}
 160
 161/*
 162 * Call it when holding delayed_node->mutex
 163 *
 164 * If mod = 1, add this node into the prepared list.
 165 */
 166static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
 167				     struct btrfs_delayed_node *node,
 168				     int mod)
 169{
 170	spin_lock(&root->lock);
 171	if (node->in_list) {
 172		if (!list_empty(&node->p_list))
 173			list_move_tail(&node->p_list, &root->prepare_list);
 174		else if (mod)
 175			list_add_tail(&node->p_list, &root->prepare_list);
 176	} else {
 177		list_add_tail(&node->n_list, &root->node_list);
 178		list_add_tail(&node->p_list, &root->prepare_list);
 179		atomic_inc(&node->refs);	/* inserted into list */
 180		root->nodes++;
 181		node->in_list = 1;
 182	}
 183	spin_unlock(&root->lock);
 184}
 185
 186/* Call it when holding delayed_node->mutex */
 187static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
 188				       struct btrfs_delayed_node *node)
 189{
 190	spin_lock(&root->lock);
 191	if (node->in_list) {
 192		root->nodes--;
 193		atomic_dec(&node->refs);	/* not in the list */
 194		list_del_init(&node->n_list);
 195		if (!list_empty(&node->p_list))
 196			list_del_init(&node->p_list);
 197		node->in_list = 0;
 198	}
 199	spin_unlock(&root->lock);
 200}
 201
 202struct btrfs_delayed_node *btrfs_first_delayed_node(
 203			struct btrfs_delayed_root *delayed_root)
 204{
 205	struct list_head *p;
 206	struct btrfs_delayed_node *node = NULL;
 207
 208	spin_lock(&delayed_root->lock);
 209	if (list_empty(&delayed_root->node_list))
 210		goto out;
 211
 212	p = delayed_root->node_list.next;
 213	node = list_entry(p, struct btrfs_delayed_node, n_list);
 214	atomic_inc(&node->refs);
 215out:
 216	spin_unlock(&delayed_root->lock);
 217
 218	return node;
 219}
 220
 221struct btrfs_delayed_node *btrfs_next_delayed_node(
 222						struct btrfs_delayed_node *node)
 223{
 224	struct btrfs_delayed_root *delayed_root;
 225	struct list_head *p;
 226	struct btrfs_delayed_node *next = NULL;
 227
 228	delayed_root = node->root->fs_info->delayed_root;
 229	spin_lock(&delayed_root->lock);
 230	if (!node->in_list) {	/* not in the list */
 
 231		if (list_empty(&delayed_root->node_list))
 232			goto out;
 233		p = delayed_root->node_list.next;
 234	} else if (list_is_last(&node->n_list, &delayed_root->node_list))
 235		goto out;
 236	else
 237		p = node->n_list.next;
 238
 239	next = list_entry(p, struct btrfs_delayed_node, n_list);
 240	atomic_inc(&next->refs);
 241out:
 242	spin_unlock(&delayed_root->lock);
 243
 244	return next;
 245}
 246
 247static void __btrfs_release_delayed_node(
 248				struct btrfs_delayed_node *delayed_node,
 249				int mod)
 250{
 251	struct btrfs_delayed_root *delayed_root;
 252
 253	if (!delayed_node)
 254		return;
 255
 256	delayed_root = delayed_node->root->fs_info->delayed_root;
 257
 258	mutex_lock(&delayed_node->mutex);
 259	if (delayed_node->count)
 260		btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
 261	else
 262		btrfs_dequeue_delayed_node(delayed_root, delayed_node);
 263	mutex_unlock(&delayed_node->mutex);
 264
 265	if (atomic_dec_and_test(&delayed_node->refs)) {
 266		struct btrfs_root *root = delayed_node->root;
 267		spin_lock(&root->inode_lock);
 268		if (atomic_read(&delayed_node->refs) == 0) {
 269			radix_tree_delete(&root->delayed_nodes_tree,
 270					  delayed_node->inode_id);
 271			kmem_cache_free(delayed_node_cache, delayed_node);
 272		}
 273		spin_unlock(&root->inode_lock);
 274	}
 275}
 276
 277static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 278{
 279	__btrfs_release_delayed_node(node, 0);
 280}
 281
 282struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 283					struct btrfs_delayed_root *delayed_root)
 284{
 285	struct list_head *p;
 286	struct btrfs_delayed_node *node = NULL;
 287
 288	spin_lock(&delayed_root->lock);
 289	if (list_empty(&delayed_root->prepare_list))
 290		goto out;
 291
 292	p = delayed_root->prepare_list.next;
 293	list_del_init(p);
 294	node = list_entry(p, struct btrfs_delayed_node, p_list);
 295	atomic_inc(&node->refs);
 296out:
 297	spin_unlock(&delayed_root->lock);
 298
 299	return node;
 300}
 301
 302static inline void btrfs_release_prepared_delayed_node(
 303					struct btrfs_delayed_node *node)
 304{
 305	__btrfs_release_delayed_node(node, 1);
 306}
 307
 308struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
 309{
 310	struct btrfs_delayed_item *item;
 311	item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
 312	if (item) {
 313		item->data_len = data_len;
 314		item->ins_or_del = 0;
 315		item->bytes_reserved = 0;
 316		item->delayed_node = NULL;
 317		atomic_set(&item->refs, 1);
 318	}
 319	return item;
 320}
 321
 322/*
 323 * __btrfs_lookup_delayed_item - look up the delayed item by key
 324 * @delayed_node: pointer to the delayed node
 325 * @key:	  the key to look up
 326 * @prev:	  used to store the prev item if the right item isn't found
 327 * @next:	  used to store the next item if the right item isn't found
 328 *
 329 * Note: if we don't find the right item, we will return the prev item and
 330 * the next item.
 331 */
 332static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 333				struct rb_root *root,
 334				struct btrfs_key *key,
 335				struct btrfs_delayed_item **prev,
 336				struct btrfs_delayed_item **next)
 337{
 338	struct rb_node *node, *prev_node = NULL;
 339	struct btrfs_delayed_item *delayed_item = NULL;
 340	int ret = 0;
 341
 342	node = root->rb_node;
 343
 344	while (node) {
 345		delayed_item = rb_entry(node, struct btrfs_delayed_item,
 346					rb_node);
 347		prev_node = node;
 348		ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
 349		if (ret < 0)
 350			node = node->rb_right;
 351		else if (ret > 0)
 352			node = node->rb_left;
 353		else
 354			return delayed_item;
 355	}
 356
 357	if (prev) {
 358		if (!prev_node)
 359			*prev = NULL;
 360		else if (ret < 0)
 361			*prev = delayed_item;
 362		else if ((node = rb_prev(prev_node)) != NULL) {
 363			*prev = rb_entry(node, struct btrfs_delayed_item,
 364					 rb_node);
 365		} else
 366			*prev = NULL;
 367	}
 368
 369	if (next) {
 370		if (!prev_node)
 371			*next = NULL;
 372		else if (ret > 0)
 373			*next = delayed_item;
 374		else if ((node = rb_next(prev_node)) != NULL) {
 375			*next = rb_entry(node, struct btrfs_delayed_item,
 376					 rb_node);
 377		} else
 378			*next = NULL;
 379	}
 380	return NULL;
 381}
 382
 383struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
 384					struct btrfs_delayed_node *delayed_node,
 385					struct btrfs_key *key)
 386{
 387	struct btrfs_delayed_item *item;
 388
 389	item = __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
 390					   NULL, NULL);
 391	return item;
 392}
 393
 394struct btrfs_delayed_item *__btrfs_lookup_delayed_deletion_item(
 395					struct btrfs_delayed_node *delayed_node,
 396					struct btrfs_key *key)
 397{
 398	struct btrfs_delayed_item *item;
 399
 400	item = __btrfs_lookup_delayed_item(&delayed_node->del_root, key,
 401					   NULL, NULL);
 402	return item;
 403}
 404
 405struct btrfs_delayed_item *__btrfs_search_delayed_insertion_item(
 406					struct btrfs_delayed_node *delayed_node,
 407					struct btrfs_key *key)
 408{
 409	struct btrfs_delayed_item *item, *next;
 410
 411	item = __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
 412					   NULL, &next);
 413	if (!item)
 414		item = next;
 415
 416	return item;
 417}
 418
 419struct btrfs_delayed_item *__btrfs_search_delayed_deletion_item(
 420					struct btrfs_delayed_node *delayed_node,
 421					struct btrfs_key *key)
 422{
 423	struct btrfs_delayed_item *item, *next;
 424
 425	item = __btrfs_lookup_delayed_item(&delayed_node->del_root, key,
 426					   NULL, &next);
 427	if (!item)
 428		item = next;
 429
 430	return item;
 431}
 432
 433static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 434				    struct btrfs_delayed_item *ins,
 435				    int action)
 436{
 437	struct rb_node **p, *node;
 438	struct rb_node *parent_node = NULL;
 439	struct rb_root *root;
 440	struct btrfs_delayed_item *item;
 441	int cmp;
 442
 443	if (action == BTRFS_DELAYED_INSERTION_ITEM)
 444		root = &delayed_node->ins_root;
 445	else if (action == BTRFS_DELAYED_DELETION_ITEM)
 446		root = &delayed_node->del_root;
 447	else
 448		BUG();
 449	p = &root->rb_node;
 450	node = &ins->rb_node;
 451
 452	while (*p) {
 453		parent_node = *p;
 454		item = rb_entry(parent_node, struct btrfs_delayed_item,
 455				 rb_node);
 456
 457		cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
 458		if (cmp < 0)
 459			p = &(*p)->rb_right;
 460		else if (cmp > 0)
 461			p = &(*p)->rb_left;
 462		else
 463			return -EEXIST;
 464	}
 465
 466	rb_link_node(node, parent_node, p);
 467	rb_insert_color(node, root);
 468	ins->delayed_node = delayed_node;
 469	ins->ins_or_del = action;
 470
 471	if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
 472	    action == BTRFS_DELAYED_INSERTION_ITEM &&
 473	    ins->key.offset >= delayed_node->index_cnt)
 474			delayed_node->index_cnt = ins->key.offset + 1;
 475
 476	delayed_node->count++;
 477	atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 478	return 0;
 479}
 480
 481static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
 482					      struct btrfs_delayed_item *item)
 483{
 484	return __btrfs_add_delayed_item(node, item,
 485					BTRFS_DELAYED_INSERTION_ITEM);
 486}
 487
 488static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 489					     struct btrfs_delayed_item *item)
 490{
 491	return __btrfs_add_delayed_item(node, item,
 492					BTRFS_DELAYED_DELETION_ITEM);
 493}
 494
 
 
 
 
 
 
 
 
 
 495static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 496{
 497	struct rb_root *root;
 498	struct btrfs_delayed_root *delayed_root;
 499
 500	delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
 501
 502	BUG_ON(!delayed_root);
 503	BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
 504	       delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
 505
 506	if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
 507		root = &delayed_item->delayed_node->ins_root;
 508	else
 509		root = &delayed_item->delayed_node->del_root;
 510
 511	rb_erase(&delayed_item->rb_node, root);
 512	delayed_item->delayed_node->count--;
 513	atomic_dec(&delayed_root->items);
 514	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND &&
 515	    waitqueue_active(&delayed_root->wait))
 516		wake_up(&delayed_root->wait);
 517}
 518
 519static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 520{
 521	if (item) {
 522		__btrfs_remove_delayed_item(item);
 523		if (atomic_dec_and_test(&item->refs))
 524			kfree(item);
 525	}
 526}
 527
 528struct btrfs_delayed_item *__btrfs_first_delayed_insertion_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->ins_root);
 535	if (p)
 536		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 537
 538	return item;
 539}
 540
 541struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 542					struct btrfs_delayed_node *delayed_node)
 543{
 544	struct rb_node *p;
 545	struct btrfs_delayed_item *item = NULL;
 546
 547	p = rb_first(&delayed_node->del_root);
 548	if (p)
 549		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 550
 551	return item;
 552}
 553
 554struct btrfs_delayed_item *__btrfs_next_delayed_item(
 555						struct btrfs_delayed_item *item)
 556{
 557	struct rb_node *p;
 558	struct btrfs_delayed_item *next = NULL;
 559
 560	p = rb_next(&item->rb_node);
 561	if (p)
 562		next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 563
 564	return next;
 565}
 566
 567static inline struct btrfs_root *btrfs_get_fs_root(struct btrfs_root *root,
 568						   u64 root_id)
 569{
 570	struct btrfs_key root_key;
 571
 572	if (root->objectid == root_id)
 573		return root;
 574
 575	root_key.objectid = root_id;
 576	root_key.type = BTRFS_ROOT_ITEM_KEY;
 577	root_key.offset = (u64)-1;
 578	return btrfs_read_fs_root_no_name(root->fs_info, &root_key);
 579}
 580
 581static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 582					       struct btrfs_root *root,
 583					       struct btrfs_delayed_item *item)
 584{
 585	struct btrfs_block_rsv *src_rsv;
 586	struct btrfs_block_rsv *dst_rsv;
 587	u64 num_bytes;
 588	int ret;
 589
 590	if (!trans->bytes_reserved)
 591		return 0;
 592
 593	src_rsv = trans->block_rsv;
 594	dst_rsv = &root->fs_info->global_block_rsv;
 595
 596	num_bytes = btrfs_calc_trans_metadata_size(root, 1);
 597	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
 598	if (!ret)
 
 
 
 599		item->bytes_reserved = num_bytes;
 
 600
 601	return ret;
 602}
 603
 604static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
 605						struct btrfs_delayed_item *item)
 606{
 607	struct btrfs_block_rsv *rsv;
 608
 609	if (!item->bytes_reserved)
 610		return;
 611
 612	rsv = &root->fs_info->global_block_rsv;
 
 
 
 613	btrfs_block_rsv_release(root, rsv,
 614				item->bytes_reserved);
 615}
 616
 617static int btrfs_delayed_inode_reserve_metadata(
 618					struct btrfs_trans_handle *trans,
 619					struct btrfs_root *root,
 
 620					struct btrfs_delayed_node *node)
 621{
 622	struct btrfs_block_rsv *src_rsv;
 623	struct btrfs_block_rsv *dst_rsv;
 624	u64 num_bytes;
 625	int ret;
 626
 627	if (!trans->bytes_reserved)
 628		return 0;
 629
 630	src_rsv = trans->block_rsv;
 631	dst_rsv = &root->fs_info->global_block_rsv;
 632
 633	num_bytes = btrfs_calc_trans_metadata_size(root, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 634	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
 635	if (!ret)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 636		node->bytes_reserved = num_bytes;
 
 
 
 
 
 
 
 637
 638	return ret;
 639}
 640
 641static void btrfs_delayed_inode_release_metadata(struct btrfs_root *root,
 642						struct btrfs_delayed_node *node)
 643{
 644	struct btrfs_block_rsv *rsv;
 645
 646	if (!node->bytes_reserved)
 647		return;
 648
 649	rsv = &root->fs_info->global_block_rsv;
 
 
 650	btrfs_block_rsv_release(root, rsv,
 651				node->bytes_reserved);
 652	node->bytes_reserved = 0;
 653}
 654
 655/*
 656 * This helper will insert some continuous items into the same leaf according
 657 * to the free space of the leaf.
 658 */
 659static int btrfs_batch_insert_items(struct btrfs_trans_handle *trans,
 660				struct btrfs_root *root,
 661				struct btrfs_path *path,
 662				struct btrfs_delayed_item *item)
 663{
 664	struct btrfs_delayed_item *curr, *next;
 665	int free_space;
 666	int total_data_size = 0, total_size = 0;
 667	struct extent_buffer *leaf;
 668	char *data_ptr;
 669	struct btrfs_key *keys;
 670	u32 *data_size;
 671	struct list_head head;
 672	int slot;
 673	int nitems;
 674	int i;
 675	int ret = 0;
 676
 677	BUG_ON(!path->nodes[0]);
 678
 679	leaf = path->nodes[0];
 680	free_space = btrfs_leaf_free_space(root, leaf);
 681	INIT_LIST_HEAD(&head);
 682
 683	next = item;
 684	nitems = 0;
 685
 686	/*
 687	 * count the number of the continuous items that we can insert in batch
 688	 */
 689	while (total_size + next->data_len + sizeof(struct btrfs_item) <=
 690	       free_space) {
 691		total_data_size += next->data_len;
 692		total_size += next->data_len + sizeof(struct btrfs_item);
 693		list_add_tail(&next->tree_list, &head);
 694		nitems++;
 695
 696		curr = next;
 697		next = __btrfs_next_delayed_item(curr);
 698		if (!next)
 699			break;
 700
 701		if (!btrfs_is_continuous_delayed_item(curr, next))
 702			break;
 703	}
 704
 705	if (!nitems) {
 706		ret = 0;
 707		goto out;
 708	}
 709
 710	/*
 711	 * we need allocate some memory space, but it might cause the task
 712	 * to sleep, so we set all locked nodes in the path to blocking locks
 713	 * first.
 714	 */
 715	btrfs_set_path_blocking(path);
 716
 717	keys = kmalloc(sizeof(struct btrfs_key) * nitems, GFP_NOFS);
 718	if (!keys) {
 719		ret = -ENOMEM;
 720		goto out;
 721	}
 722
 723	data_size = kmalloc(sizeof(u32) * nitems, GFP_NOFS);
 724	if (!data_size) {
 725		ret = -ENOMEM;
 726		goto error;
 727	}
 728
 729	/* get keys of all the delayed items */
 730	i = 0;
 731	list_for_each_entry(next, &head, tree_list) {
 732		keys[i] = next->key;
 733		data_size[i] = next->data_len;
 734		i++;
 735	}
 736
 737	/* reset all the locked nodes in the patch to spinning locks. */
 738	btrfs_clear_path_blocking(path, NULL, 0);
 739
 740	/* insert the keys of the items */
 741	ret = setup_items_for_insert(trans, root, path, keys, data_size,
 742				     total_data_size, total_size, nitems);
 743	if (ret)
 744		goto error;
 745
 746	/* insert the dir index items */
 747	slot = path->slots[0];
 748	list_for_each_entry_safe(curr, next, &head, tree_list) {
 749		data_ptr = btrfs_item_ptr(leaf, slot, char);
 750		write_extent_buffer(leaf, &curr->data,
 751				    (unsigned long)data_ptr,
 752				    curr->data_len);
 753		slot++;
 754
 755		btrfs_delayed_item_release_metadata(root, curr);
 756
 757		list_del(&curr->tree_list);
 758		btrfs_release_delayed_item(curr);
 759	}
 760
 761error:
 762	kfree(data_size);
 763	kfree(keys);
 764out:
 765	return ret;
 766}
 767
 768/*
 769 * This helper can just do simple insertion that needn't extend item for new
 770 * data, such as directory name index insertion, inode insertion.
 771 */
 772static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 773				     struct btrfs_root *root,
 774				     struct btrfs_path *path,
 775				     struct btrfs_delayed_item *delayed_item)
 776{
 777	struct extent_buffer *leaf;
 778	struct btrfs_item *item;
 779	char *ptr;
 780	int ret;
 781
 782	ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
 783				      delayed_item->data_len);
 784	if (ret < 0 && ret != -EEXIST)
 785		return ret;
 786
 787	leaf = path->nodes[0];
 788
 789	item = btrfs_item_nr(leaf, path->slots[0]);
 790	ptr = btrfs_item_ptr(leaf, path->slots[0], char);
 791
 792	write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
 793			    delayed_item->data_len);
 794	btrfs_mark_buffer_dirty(leaf);
 795
 796	btrfs_delayed_item_release_metadata(root, delayed_item);
 797	return 0;
 798}
 799
 800/*
 801 * we insert an item first, then if there are some continuous items, we try
 802 * to insert those items into the same leaf.
 803 */
 804static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 805				      struct btrfs_path *path,
 806				      struct btrfs_root *root,
 807				      struct btrfs_delayed_node *node)
 808{
 809	struct btrfs_delayed_item *curr, *prev;
 810	int ret = 0;
 811
 812do_again:
 813	mutex_lock(&node->mutex);
 814	curr = __btrfs_first_delayed_insertion_item(node);
 815	if (!curr)
 816		goto insert_end;
 817
 818	ret = btrfs_insert_delayed_item(trans, root, path, curr);
 819	if (ret < 0) {
 820		btrfs_release_path(path);
 821		goto insert_end;
 822	}
 823
 824	prev = curr;
 825	curr = __btrfs_next_delayed_item(prev);
 826	if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
 827		/* insert the continuous items into the same leaf */
 828		path->slots[0]++;
 829		btrfs_batch_insert_items(trans, root, path, curr);
 830	}
 831	btrfs_release_delayed_item(prev);
 832	btrfs_mark_buffer_dirty(path->nodes[0]);
 833
 834	btrfs_release_path(path);
 835	mutex_unlock(&node->mutex);
 836	goto do_again;
 837
 838insert_end:
 839	mutex_unlock(&node->mutex);
 840	return ret;
 841}
 842
 843static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
 844				    struct btrfs_root *root,
 845				    struct btrfs_path *path,
 846				    struct btrfs_delayed_item *item)
 847{
 848	struct btrfs_delayed_item *curr, *next;
 849	struct extent_buffer *leaf;
 850	struct btrfs_key key;
 851	struct list_head head;
 852	int nitems, i, last_item;
 853	int ret = 0;
 854
 855	BUG_ON(!path->nodes[0]);
 856
 857	leaf = path->nodes[0];
 858
 859	i = path->slots[0];
 860	last_item = btrfs_header_nritems(leaf) - 1;
 861	if (i > last_item)
 862		return -ENOENT;	/* FIXME: Is errno suitable? */
 863
 864	next = item;
 865	INIT_LIST_HEAD(&head);
 866	btrfs_item_key_to_cpu(leaf, &key, i);
 867	nitems = 0;
 868	/*
 869	 * count the number of the dir index items that we can delete in batch
 870	 */
 871	while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
 872		list_add_tail(&next->tree_list, &head);
 873		nitems++;
 874
 875		curr = next;
 876		next = __btrfs_next_delayed_item(curr);
 877		if (!next)
 878			break;
 879
 880		if (!btrfs_is_continuous_delayed_item(curr, next))
 881			break;
 882
 883		i++;
 884		if (i > last_item)
 885			break;
 886		btrfs_item_key_to_cpu(leaf, &key, i);
 887	}
 888
 889	if (!nitems)
 890		return 0;
 891
 892	ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 893	if (ret)
 894		goto out;
 895
 896	list_for_each_entry_safe(curr, next, &head, tree_list) {
 897		btrfs_delayed_item_release_metadata(root, curr);
 898		list_del(&curr->tree_list);
 899		btrfs_release_delayed_item(curr);
 900	}
 901
 902out:
 903	return ret;
 904}
 905
 906static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 907				      struct btrfs_path *path,
 908				      struct btrfs_root *root,
 909				      struct btrfs_delayed_node *node)
 910{
 911	struct btrfs_delayed_item *curr, *prev;
 912	int ret = 0;
 913
 914do_again:
 915	mutex_lock(&node->mutex);
 916	curr = __btrfs_first_delayed_deletion_item(node);
 917	if (!curr)
 918		goto delete_fail;
 919
 920	ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
 921	if (ret < 0)
 922		goto delete_fail;
 923	else if (ret > 0) {
 924		/*
 925		 * can't find the item which the node points to, so this node
 926		 * is invalid, just drop it.
 927		 */
 928		prev = curr;
 929		curr = __btrfs_next_delayed_item(prev);
 930		btrfs_release_delayed_item(prev);
 931		ret = 0;
 932		btrfs_release_path(path);
 933		if (curr)
 
 934			goto do_again;
 935		else
 936			goto delete_fail;
 937	}
 938
 939	btrfs_batch_delete_items(trans, root, path, curr);
 940	btrfs_release_path(path);
 941	mutex_unlock(&node->mutex);
 942	goto do_again;
 943
 944delete_fail:
 945	btrfs_release_path(path);
 946	mutex_unlock(&node->mutex);
 947	return ret;
 948}
 949
 950static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
 951{
 952	struct btrfs_delayed_root *delayed_root;
 953
 954	if (delayed_node && delayed_node->inode_dirty) {
 
 955		BUG_ON(!delayed_node->root);
 956		delayed_node->inode_dirty = 0;
 957		delayed_node->count--;
 958
 959		delayed_root = delayed_node->root->fs_info->delayed_root;
 960		atomic_dec(&delayed_root->items);
 961		if (atomic_read(&delayed_root->items) <
 962		    BTRFS_DELAYED_BACKGROUND &&
 963		    waitqueue_active(&delayed_root->wait))
 964			wake_up(&delayed_root->wait);
 965	}
 966}
 967
 968static int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
 969				      struct btrfs_root *root,
 970				      struct btrfs_path *path,
 971				      struct btrfs_delayed_node *node)
 
 
 
 
 
 
 
 
 
 
 
 
 972{
 973	struct btrfs_key key;
 974	struct btrfs_inode_item *inode_item;
 975	struct extent_buffer *leaf;
 
 976	int ret;
 977
 978	mutex_lock(&node->mutex);
 979	if (!node->inode_dirty) {
 980		mutex_unlock(&node->mutex);
 981		return 0;
 982	}
 983
 984	key.objectid = node->inode_id;
 985	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
 986	key.offset = 0;
 987	ret = btrfs_lookup_inode(trans, root, path, &key, 1);
 
 
 
 
 
 
 988	if (ret > 0) {
 989		btrfs_release_path(path);
 990		mutex_unlock(&node->mutex);
 991		return -ENOENT;
 992	} else if (ret < 0) {
 993		mutex_unlock(&node->mutex);
 994		return ret;
 995	}
 996
 997	btrfs_unlock_up_safe(path, 1);
 998	leaf = path->nodes[0];
 999	inode_item = btrfs_item_ptr(leaf, path->slots[0],
1000				    struct btrfs_inode_item);
1001	write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1002			    sizeof(struct btrfs_inode_item));
1003	btrfs_mark_buffer_dirty(leaf);
1004	btrfs_release_path(path);
1005
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1006	btrfs_delayed_inode_release_metadata(root, node);
1007	btrfs_release_delayed_inode(node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1008	mutex_unlock(&node->mutex);
 
 
1009
1010	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1011}
1012
1013/* Called when committing the transaction. */
1014int btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1015			    struct btrfs_root *root)
 
 
 
 
 
1016{
1017	struct btrfs_delayed_root *delayed_root;
1018	struct btrfs_delayed_node *curr_node, *prev_node;
1019	struct btrfs_path *path;
1020	struct btrfs_block_rsv *block_rsv;
1021	int ret = 0;
 
 
 
 
1022
1023	path = btrfs_alloc_path();
1024	if (!path)
1025		return -ENOMEM;
1026	path->leave_spinning = 1;
1027
1028	block_rsv = trans->block_rsv;
1029	trans->block_rsv = &root->fs_info->global_block_rsv;
1030
1031	delayed_root = btrfs_get_delayed_root(root);
1032
1033	curr_node = btrfs_first_delayed_node(delayed_root);
1034	while (curr_node) {
1035		root = curr_node->root;
1036		ret = btrfs_insert_delayed_items(trans, path, root,
1037						 curr_node);
1038		if (!ret)
1039			ret = btrfs_delete_delayed_items(trans, path, root,
1040							 curr_node);
1041		if (!ret)
1042			ret = btrfs_update_delayed_inode(trans, root, path,
1043							 curr_node);
1044		if (ret) {
1045			btrfs_release_delayed_node(curr_node);
 
 
1046			break;
1047		}
1048
1049		prev_node = curr_node;
1050		curr_node = btrfs_next_delayed_node(curr_node);
1051		btrfs_release_delayed_node(prev_node);
1052	}
1053
 
 
1054	btrfs_free_path(path);
1055	trans->block_rsv = block_rsv;
 
1056	return ret;
1057}
1058
1059static int __btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1060					      struct btrfs_delayed_node *node)
 
 
 
 
 
 
1061{
 
 
 
 
 
 
 
1062	struct btrfs_path *path;
1063	struct btrfs_block_rsv *block_rsv;
1064	int ret;
1065
 
 
 
 
 
 
 
 
 
 
 
1066	path = btrfs_alloc_path();
1067	if (!path)
 
1068		return -ENOMEM;
 
1069	path->leave_spinning = 1;
1070
1071	block_rsv = trans->block_rsv;
1072	trans->block_rsv = &node->root->fs_info->global_block_rsv;
1073
1074	ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1075	if (!ret)
1076		ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1077	if (!ret)
1078		ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1079	btrfs_free_path(path);
1080
 
 
1081	trans->block_rsv = block_rsv;
 
1082	return ret;
1083}
1084
1085int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1086				     struct inode *inode)
1087{
 
1088	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
 
 
1089	int ret;
1090
1091	if (!delayed_node)
1092		return 0;
1093
1094	mutex_lock(&delayed_node->mutex);
1095	if (!delayed_node->count) {
1096		mutex_unlock(&delayed_node->mutex);
1097		btrfs_release_delayed_node(delayed_node);
1098		return 0;
1099	}
1100	mutex_unlock(&delayed_node->mutex);
1101
1102	ret = __btrfs_commit_inode_delayed_items(trans, delayed_node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1103	btrfs_release_delayed_node(delayed_node);
 
1104	return ret;
1105}
1106
1107void btrfs_remove_delayed_node(struct inode *inode)
1108{
1109	struct btrfs_delayed_node *delayed_node;
1110
1111	delayed_node = ACCESS_ONCE(BTRFS_I(inode)->delayed_node);
1112	if (!delayed_node)
1113		return;
1114
1115	BTRFS_I(inode)->delayed_node = NULL;
1116	btrfs_release_delayed_node(delayed_node);
1117}
1118
1119struct btrfs_async_delayed_node {
1120	struct btrfs_root *root;
1121	struct btrfs_delayed_node *delayed_node;
1122	struct btrfs_work work;
1123};
1124
1125static void btrfs_async_run_delayed_node_done(struct btrfs_work *work)
1126{
1127	struct btrfs_async_delayed_node *async_node;
 
1128	struct btrfs_trans_handle *trans;
1129	struct btrfs_path *path;
1130	struct btrfs_delayed_node *delayed_node = NULL;
1131	struct btrfs_root *root;
1132	struct btrfs_block_rsv *block_rsv;
1133	unsigned long nr = 0;
1134	int need_requeue = 0;
1135	int ret;
1136
1137	async_node = container_of(work, struct btrfs_async_delayed_node, work);
 
1138
1139	path = btrfs_alloc_path();
1140	if (!path)
1141		goto out;
1142	path->leave_spinning = 1;
1143
1144	delayed_node = async_node->delayed_node;
 
 
 
 
 
 
 
 
1145	root = delayed_node->root;
1146
1147	trans = btrfs_join_transaction(root);
1148	if (IS_ERR(trans))
1149		goto free_path;
1150
1151	block_rsv = trans->block_rsv;
1152	trans->block_rsv = &root->fs_info->global_block_rsv;
1153
1154	ret = btrfs_insert_delayed_items(trans, path, root, delayed_node);
1155	if (!ret)
1156		ret = btrfs_delete_delayed_items(trans, path, root,
1157						 delayed_node);
1158
1159	if (!ret)
1160		btrfs_update_delayed_inode(trans, root, path, delayed_node);
 
1161
1162	/*
1163	 * Maybe new delayed items have been inserted, so we need requeue
1164	 * the work. Besides that, we must dequeue the empty delayed nodes
1165	 * to avoid the race between delayed items balance and the worker.
1166	 * The race like this:
1167	 * 	Task1				Worker thread
1168	 * 					count == 0, needn't requeue
1169	 * 					  also needn't insert the
1170	 * 					  delayed node into prepare
1171	 * 					  list again.
1172	 * 	add lots of delayed items
1173	 * 	queue the delayed node
1174	 * 	  already in the list,
1175	 * 	  and not in the prepare
1176	 * 	  list, it means the delayed
1177	 * 	  node is being dealt with
1178	 * 	  by the worker.
1179	 * 	do delayed items balance
1180	 * 	  the delayed node is being
1181	 * 	  dealt with by the worker
1182	 * 	  now, just wait.
1183	 * 	  				the worker goto idle.
1184	 * Task1 will sleep until the transaction is commited.
1185	 */
1186	mutex_lock(&delayed_node->mutex);
1187	if (delayed_node->count)
1188		need_requeue = 1;
1189	else
1190		btrfs_dequeue_delayed_node(root->fs_info->delayed_root,
1191					   delayed_node);
1192	mutex_unlock(&delayed_node->mutex);
1193
1194	nr = trans->blocks_used;
 
 
1195
1196	trans->block_rsv = block_rsv;
1197	btrfs_end_transaction_dmeta(trans, root);
1198	__btrfs_btree_balance_dirty(root, nr);
1199free_path:
1200	btrfs_free_path(path);
1201out:
1202	if (need_requeue)
1203		btrfs_requeue_work(&async_node->work);
1204	else {
1205		btrfs_release_prepared_delayed_node(delayed_node);
1206		kfree(async_node);
1207	}
1208}
1209
 
1210static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1211				     struct btrfs_root *root, int all)
1212{
1213	struct btrfs_async_delayed_node *async_node;
1214	struct btrfs_delayed_node *curr;
1215	int count = 0;
1216
1217again:
1218	curr = btrfs_first_prepared_delayed_node(delayed_root);
1219	if (!curr)
1220		return 0;
1221
1222	async_node = kmalloc(sizeof(*async_node), GFP_NOFS);
1223	if (!async_node) {
1224		btrfs_release_prepared_delayed_node(curr);
1225		return -ENOMEM;
1226	}
1227
1228	async_node->root = root;
1229	async_node->delayed_node = curr;
1230
1231	async_node->work.func = btrfs_async_run_delayed_node_done;
1232	async_node->work.flags = 0;
1233
1234	btrfs_queue_worker(&root->fs_info->delayed_workers, &async_node->work);
1235	count++;
1236
1237	if (all || count < 4)
1238		goto again;
1239
 
1240	return 0;
1241}
1242
1243void btrfs_assert_delayed_root_empty(struct btrfs_root *root)
1244{
1245	struct btrfs_delayed_root *delayed_root;
1246	delayed_root = btrfs_get_delayed_root(root);
1247	WARN_ON(btrfs_first_delayed_node(delayed_root));
1248}
1249
 
 
 
 
 
 
 
 
 
 
 
 
 
1250void btrfs_balance_delayed_items(struct btrfs_root *root)
1251{
1252	struct btrfs_delayed_root *delayed_root;
1253
1254	delayed_root = btrfs_get_delayed_root(root);
1255
1256	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1257		return;
1258
1259	if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
 
1260		int ret;
1261		ret = btrfs_wq_run_delayed_node(delayed_root, root, 1);
 
 
 
1262		if (ret)
1263			return;
1264
1265		wait_event_interruptible_timeout(
1266				delayed_root->wait,
1267				(atomic_read(&delayed_root->items) <
1268				 BTRFS_DELAYED_BACKGROUND),
1269				HZ);
1270		return;
1271	}
1272
1273	btrfs_wq_run_delayed_node(delayed_root, root, 0);
1274}
1275
 
1276int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1277				   struct btrfs_root *root, const char *name,
1278				   int name_len, struct inode *dir,
1279				   struct btrfs_disk_key *disk_key, u8 type,
1280				   u64 index)
1281{
1282	struct btrfs_delayed_node *delayed_node;
1283	struct btrfs_delayed_item *delayed_item;
1284	struct btrfs_dir_item *dir_item;
1285	int ret;
1286
1287	delayed_node = btrfs_get_or_create_delayed_node(dir);
1288	if (IS_ERR(delayed_node))
1289		return PTR_ERR(delayed_node);
1290
1291	delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
1292	if (!delayed_item) {
1293		ret = -ENOMEM;
1294		goto release_node;
1295	}
1296
1297	ret = btrfs_delayed_item_reserve_metadata(trans, root, delayed_item);
1298	/*
1299	 * we have reserved enough space when we start a new transaction,
1300	 * so reserving metadata failure is impossible
1301	 */
1302	BUG_ON(ret);
1303
1304	delayed_item->key.objectid = btrfs_ino(dir);
1305	btrfs_set_key_type(&delayed_item->key, BTRFS_DIR_INDEX_KEY);
1306	delayed_item->key.offset = index;
1307
1308	dir_item = (struct btrfs_dir_item *)delayed_item->data;
1309	dir_item->location = *disk_key;
1310	dir_item->transid = cpu_to_le64(trans->transid);
1311	dir_item->data_len = 0;
1312	dir_item->name_len = cpu_to_le16(name_len);
1313	dir_item->type = type;
1314	memcpy((char *)(dir_item + 1), name, name_len);
1315
 
 
 
 
 
 
 
 
1316	mutex_lock(&delayed_node->mutex);
1317	ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1318	if (unlikely(ret)) {
1319		printk(KERN_ERR "err add delayed dir index item(name: %s) into "
1320				"the insertion tree of the delayed node"
1321				"(root id: %llu, inode id: %llu, errno: %d)\n",
1322				name,
1323				(unsigned long long)delayed_node->root->objectid,
1324				(unsigned long long)delayed_node->inode_id,
1325				ret);
1326		BUG();
1327	}
1328	mutex_unlock(&delayed_node->mutex);
1329
1330release_node:
1331	btrfs_release_delayed_node(delayed_node);
1332	return ret;
1333}
1334
1335static int btrfs_delete_delayed_insertion_item(struct btrfs_root *root,
1336					       struct btrfs_delayed_node *node,
1337					       struct btrfs_key *key)
1338{
1339	struct btrfs_delayed_item *item;
1340
1341	mutex_lock(&node->mutex);
1342	item = __btrfs_lookup_delayed_insertion_item(node, key);
1343	if (!item) {
1344		mutex_unlock(&node->mutex);
1345		return 1;
1346	}
1347
1348	btrfs_delayed_item_release_metadata(root, item);
1349	btrfs_release_delayed_item(item);
1350	mutex_unlock(&node->mutex);
1351	return 0;
1352}
1353
1354int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1355				   struct btrfs_root *root, struct inode *dir,
1356				   u64 index)
1357{
1358	struct btrfs_delayed_node *node;
1359	struct btrfs_delayed_item *item;
1360	struct btrfs_key item_key;
1361	int ret;
1362
1363	node = btrfs_get_or_create_delayed_node(dir);
1364	if (IS_ERR(node))
1365		return PTR_ERR(node);
1366
1367	item_key.objectid = btrfs_ino(dir);
1368	btrfs_set_key_type(&item_key, BTRFS_DIR_INDEX_KEY);
1369	item_key.offset = index;
1370
1371	ret = btrfs_delete_delayed_insertion_item(root, node, &item_key);
1372	if (!ret)
1373		goto end;
1374
1375	item = btrfs_alloc_delayed_item(0);
1376	if (!item) {
1377		ret = -ENOMEM;
1378		goto end;
1379	}
1380
1381	item->key = item_key;
1382
1383	ret = btrfs_delayed_item_reserve_metadata(trans, root, item);
1384	/*
1385	 * we have reserved enough space when we start a new transaction,
1386	 * so reserving metadata failure is impossible.
1387	 */
1388	BUG_ON(ret);
1389
1390	mutex_lock(&node->mutex);
1391	ret = __btrfs_add_delayed_deletion_item(node, item);
1392	if (unlikely(ret)) {
1393		printk(KERN_ERR "err add delayed dir index item(index: %llu) "
1394				"into the deletion tree of the delayed node"
1395				"(root id: %llu, inode id: %llu, errno: %d)\n",
1396				(unsigned long long)index,
1397				(unsigned long long)node->root->objectid,
1398				(unsigned long long)node->inode_id,
1399				ret);
1400		BUG();
1401	}
1402	mutex_unlock(&node->mutex);
1403end:
1404	btrfs_release_delayed_node(node);
1405	return ret;
1406}
1407
1408int btrfs_inode_delayed_dir_index_count(struct inode *inode)
1409{
1410	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1411
1412	if (!delayed_node)
1413		return -ENOENT;
1414
1415	/*
1416	 * Since we have held i_mutex of this directory, it is impossible that
1417	 * a new directory index is added into the delayed node and index_cnt
1418	 * is updated now. So we needn't lock the delayed node.
1419	 */
1420	if (!delayed_node->index_cnt) {
1421		btrfs_release_delayed_node(delayed_node);
1422		return -EINVAL;
1423	}
1424
1425	BTRFS_I(inode)->index_cnt = delayed_node->index_cnt;
1426	btrfs_release_delayed_node(delayed_node);
1427	return 0;
1428}
1429
1430void btrfs_get_delayed_items(struct inode *inode, struct list_head *ins_list,
1431			     struct list_head *del_list)
1432{
1433	struct btrfs_delayed_node *delayed_node;
1434	struct btrfs_delayed_item *item;
1435
1436	delayed_node = btrfs_get_delayed_node(inode);
1437	if (!delayed_node)
1438		return;
1439
1440	mutex_lock(&delayed_node->mutex);
1441	item = __btrfs_first_delayed_insertion_item(delayed_node);
1442	while (item) {
1443		atomic_inc(&item->refs);
1444		list_add_tail(&item->readdir_list, ins_list);
1445		item = __btrfs_next_delayed_item(item);
1446	}
1447
1448	item = __btrfs_first_delayed_deletion_item(delayed_node);
1449	while (item) {
1450		atomic_inc(&item->refs);
1451		list_add_tail(&item->readdir_list, del_list);
1452		item = __btrfs_next_delayed_item(item);
1453	}
1454	mutex_unlock(&delayed_node->mutex);
1455	/*
1456	 * This delayed node is still cached in the btrfs inode, so refs
1457	 * must be > 1 now, and we needn't check it is going to be freed
1458	 * or not.
1459	 *
1460	 * Besides that, this function is used to read dir, we do not
1461	 * insert/delete delayed items in this period. So we also needn't
1462	 * requeue or dequeue this delayed node.
1463	 */
1464	atomic_dec(&delayed_node->refs);
1465}
1466
1467void btrfs_put_delayed_items(struct list_head *ins_list,
1468			     struct list_head *del_list)
1469{
1470	struct btrfs_delayed_item *curr, *next;
1471
1472	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1473		list_del(&curr->readdir_list);
1474		if (atomic_dec_and_test(&curr->refs))
1475			kfree(curr);
1476	}
1477
1478	list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1479		list_del(&curr->readdir_list);
1480		if (atomic_dec_and_test(&curr->refs))
1481			kfree(curr);
1482	}
1483}
1484
1485int btrfs_should_delete_dir_index(struct list_head *del_list,
1486				  u64 index)
1487{
1488	struct btrfs_delayed_item *curr, *next;
1489	int ret;
1490
1491	if (list_empty(del_list))
1492		return 0;
1493
1494	list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1495		if (curr->key.offset > index)
1496			break;
1497
1498		list_del(&curr->readdir_list);
1499		ret = (curr->key.offset == index);
1500
1501		if (atomic_dec_and_test(&curr->refs))
1502			kfree(curr);
1503
1504		if (ret)
1505			return 1;
1506		else
1507			continue;
1508	}
1509	return 0;
1510}
1511
1512/*
1513 * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1514 *
1515 */
1516int btrfs_readdir_delayed_dir_index(struct file *filp, void *dirent,
1517				    filldir_t filldir,
1518				    struct list_head *ins_list)
1519{
1520	struct btrfs_dir_item *di;
1521	struct btrfs_delayed_item *curr, *next;
1522	struct btrfs_key location;
1523	char *name;
1524	int name_len;
1525	int over = 0;
1526	unsigned char d_type;
1527
1528	if (list_empty(ins_list))
1529		return 0;
1530
1531	/*
1532	 * Changing the data of the delayed item is impossible. So
1533	 * we needn't lock them. And we have held i_mutex of the
1534	 * directory, nobody can delete any directory indexes now.
1535	 */
1536	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1537		list_del(&curr->readdir_list);
1538
1539		if (curr->key.offset < filp->f_pos) {
1540			if (atomic_dec_and_test(&curr->refs))
1541				kfree(curr);
1542			continue;
1543		}
1544
1545		filp->f_pos = curr->key.offset;
1546
1547		di = (struct btrfs_dir_item *)curr->data;
1548		name = (char *)(di + 1);
1549		name_len = le16_to_cpu(di->name_len);
1550
1551		d_type = btrfs_filetype_table[di->type];
1552		btrfs_disk_key_to_cpu(&location, &di->location);
1553
1554		over = filldir(dirent, name, name_len, curr->key.offset,
1555			       location.objectid, d_type);
1556
1557		if (atomic_dec_and_test(&curr->refs))
1558			kfree(curr);
1559
1560		if (over)
1561			return 1;
1562	}
1563	return 0;
1564}
1565
1566BTRFS_SETGET_STACK_FUNCS(stack_inode_generation, struct btrfs_inode_item,
1567			 generation, 64);
1568BTRFS_SETGET_STACK_FUNCS(stack_inode_sequence, struct btrfs_inode_item,
1569			 sequence, 64);
1570BTRFS_SETGET_STACK_FUNCS(stack_inode_transid, struct btrfs_inode_item,
1571			 transid, 64);
1572BTRFS_SETGET_STACK_FUNCS(stack_inode_size, struct btrfs_inode_item, size, 64);
1573BTRFS_SETGET_STACK_FUNCS(stack_inode_nbytes, struct btrfs_inode_item,
1574			 nbytes, 64);
1575BTRFS_SETGET_STACK_FUNCS(stack_inode_block_group, struct btrfs_inode_item,
1576			 block_group, 64);
1577BTRFS_SETGET_STACK_FUNCS(stack_inode_nlink, struct btrfs_inode_item, nlink, 32);
1578BTRFS_SETGET_STACK_FUNCS(stack_inode_uid, struct btrfs_inode_item, uid, 32);
1579BTRFS_SETGET_STACK_FUNCS(stack_inode_gid, struct btrfs_inode_item, gid, 32);
1580BTRFS_SETGET_STACK_FUNCS(stack_inode_mode, struct btrfs_inode_item, mode, 32);
1581BTRFS_SETGET_STACK_FUNCS(stack_inode_rdev, struct btrfs_inode_item, rdev, 64);
1582BTRFS_SETGET_STACK_FUNCS(stack_inode_flags, struct btrfs_inode_item, flags, 64);
1583
1584BTRFS_SETGET_STACK_FUNCS(stack_timespec_sec, struct btrfs_timespec, sec, 64);
1585BTRFS_SETGET_STACK_FUNCS(stack_timespec_nsec, struct btrfs_timespec, nsec, 32);
1586
1587static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1588				  struct btrfs_inode_item *inode_item,
1589				  struct inode *inode)
1590{
1591	btrfs_set_stack_inode_uid(inode_item, inode->i_uid);
1592	btrfs_set_stack_inode_gid(inode_item, inode->i_gid);
1593	btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1594	btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1595	btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1596	btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1597	btrfs_set_stack_inode_generation(inode_item,
1598					 BTRFS_I(inode)->generation);
1599	btrfs_set_stack_inode_sequence(inode_item, BTRFS_I(inode)->sequence);
1600	btrfs_set_stack_inode_transid(inode_item, trans->transid);
1601	btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1602	btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
1603	btrfs_set_stack_inode_block_group(inode_item, 0);
1604
1605	btrfs_set_stack_timespec_sec(btrfs_inode_atime(inode_item),
1606				     inode->i_atime.tv_sec);
1607	btrfs_set_stack_timespec_nsec(btrfs_inode_atime(inode_item),
1608				      inode->i_atime.tv_nsec);
1609
1610	btrfs_set_stack_timespec_sec(btrfs_inode_mtime(inode_item),
1611				     inode->i_mtime.tv_sec);
1612	btrfs_set_stack_timespec_nsec(btrfs_inode_mtime(inode_item),
1613				      inode->i_mtime.tv_nsec);
1614
1615	btrfs_set_stack_timespec_sec(btrfs_inode_ctime(inode_item),
1616				     inode->i_ctime.tv_sec);
1617	btrfs_set_stack_timespec_nsec(btrfs_inode_ctime(inode_item),
1618				      inode->i_ctime.tv_nsec);
1619}
1620
1621int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1622{
1623	struct btrfs_delayed_node *delayed_node;
1624	struct btrfs_inode_item *inode_item;
1625	struct btrfs_timespec *tspec;
1626
1627	delayed_node = btrfs_get_delayed_node(inode);
1628	if (!delayed_node)
1629		return -ENOENT;
1630
1631	mutex_lock(&delayed_node->mutex);
1632	if (!delayed_node->inode_dirty) {
1633		mutex_unlock(&delayed_node->mutex);
1634		btrfs_release_delayed_node(delayed_node);
1635		return -ENOENT;
1636	}
1637
1638	inode_item = &delayed_node->inode_item;
1639
1640	inode->i_uid = btrfs_stack_inode_uid(inode_item);
1641	inode->i_gid = btrfs_stack_inode_gid(inode_item);
1642	btrfs_i_size_write(inode, btrfs_stack_inode_size(inode_item));
1643	inode->i_mode = btrfs_stack_inode_mode(inode_item);
1644	inode->i_nlink = btrfs_stack_inode_nlink(inode_item);
1645	inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1646	BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1647	BTRFS_I(inode)->sequence = btrfs_stack_inode_sequence(inode_item);
1648	inode->i_rdev = 0;
1649	*rdev = btrfs_stack_inode_rdev(inode_item);
1650	BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
1651
1652	tspec = btrfs_inode_atime(inode_item);
1653	inode->i_atime.tv_sec = btrfs_stack_timespec_sec(tspec);
1654	inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1655
1656	tspec = btrfs_inode_mtime(inode_item);
1657	inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(tspec);
1658	inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1659
1660	tspec = btrfs_inode_ctime(inode_item);
1661	inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(tspec);
1662	inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1663
1664	inode->i_generation = BTRFS_I(inode)->generation;
1665	BTRFS_I(inode)->index_cnt = (u64)-1;
1666
1667	mutex_unlock(&delayed_node->mutex);
1668	btrfs_release_delayed_node(delayed_node);
1669	return 0;
1670}
1671
1672int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1673			       struct btrfs_root *root, struct inode *inode)
1674{
1675	struct btrfs_delayed_node *delayed_node;
1676	int ret = 0;
1677
1678	delayed_node = btrfs_get_or_create_delayed_node(inode);
1679	if (IS_ERR(delayed_node))
1680		return PTR_ERR(delayed_node);
1681
1682	mutex_lock(&delayed_node->mutex);
1683	if (delayed_node->inode_dirty) {
1684		fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1685		goto release_node;
1686	}
1687
1688	ret = btrfs_delayed_inode_reserve_metadata(trans, root, delayed_node);
1689	/*
1690	 * we must reserve enough space when we start a new transaction,
1691	 * so reserving metadata failure is impossible
1692	 */
1693	BUG_ON(ret);
1694
1695	fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1696	delayed_node->inode_dirty = 1;
1697	delayed_node->count++;
1698	atomic_inc(&root->fs_info->delayed_root->items);
1699release_node:
1700	mutex_unlock(&delayed_node->mutex);
1701	btrfs_release_delayed_node(delayed_node);
1702	return ret;
1703}
1704
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1705static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1706{
1707	struct btrfs_root *root = delayed_node->root;
1708	struct btrfs_delayed_item *curr_item, *prev_item;
1709
1710	mutex_lock(&delayed_node->mutex);
1711	curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1712	while (curr_item) {
1713		btrfs_delayed_item_release_metadata(root, curr_item);
1714		prev_item = curr_item;
1715		curr_item = __btrfs_next_delayed_item(prev_item);
1716		btrfs_release_delayed_item(prev_item);
1717	}
1718
1719	curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1720	while (curr_item) {
1721		btrfs_delayed_item_release_metadata(root, curr_item);
1722		prev_item = curr_item;
1723		curr_item = __btrfs_next_delayed_item(prev_item);
1724		btrfs_release_delayed_item(prev_item);
1725	}
1726
1727	if (delayed_node->inode_dirty) {
 
 
 
1728		btrfs_delayed_inode_release_metadata(root, delayed_node);
1729		btrfs_release_delayed_inode(delayed_node);
1730	}
1731	mutex_unlock(&delayed_node->mutex);
1732}
1733
1734void btrfs_kill_delayed_inode_items(struct inode *inode)
1735{
1736	struct btrfs_delayed_node *delayed_node;
1737
1738	delayed_node = btrfs_get_delayed_node(inode);
1739	if (!delayed_node)
1740		return;
1741
1742	__btrfs_kill_delayed_node(delayed_node);
1743	btrfs_release_delayed_node(delayed_node);
1744}
1745
1746void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1747{
1748	u64 inode_id = 0;
1749	struct btrfs_delayed_node *delayed_nodes[8];
1750	int i, n;
1751
1752	while (1) {
1753		spin_lock(&root->inode_lock);
1754		n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1755					   (void **)delayed_nodes, inode_id,
1756					   ARRAY_SIZE(delayed_nodes));
1757		if (!n) {
1758			spin_unlock(&root->inode_lock);
1759			break;
1760		}
1761
1762		inode_id = delayed_nodes[n - 1]->inode_id + 1;
1763
1764		for (i = 0; i < n; i++)
1765			atomic_inc(&delayed_nodes[i]->refs);
1766		spin_unlock(&root->inode_lock);
1767
1768		for (i = 0; i < n; i++) {
1769			__btrfs_kill_delayed_node(delayed_nodes[i]);
1770			btrfs_release_delayed_node(delayed_nodes[i]);
1771		}
1772	}
1773}
v3.15
   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 "delayed-inode.h"
  22#include "disk-io.h"
  23#include "transaction.h"
  24#include "ctree.h"
  25
  26#define BTRFS_DELAYED_WRITEBACK		512
  27#define BTRFS_DELAYED_BACKGROUND	128
  28#define BTRFS_DELAYED_BATCH		16
  29
  30static struct kmem_cache *delayed_node_cache;
  31
  32int __init btrfs_delayed_inode_init(void)
  33{
  34	delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
  35					sizeof(struct btrfs_delayed_node),
  36					0,
  37					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
  38					NULL);
  39	if (!delayed_node_cache)
  40		return -ENOMEM;
  41	return 0;
  42}
  43
  44void btrfs_delayed_inode_exit(void)
  45{
  46	if (delayed_node_cache)
  47		kmem_cache_destroy(delayed_node_cache);
  48}
  49
  50static 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	atomic_set(&delayed_node->refs, 0);
  57	delayed_node->count = 0;
  58	delayed_node->flags = 0;
 
  59	delayed_node->ins_root = RB_ROOT;
  60	delayed_node->del_root = RB_ROOT;
  61	mutex_init(&delayed_node->mutex);
  62	delayed_node->index_cnt = 0;
  63	INIT_LIST_HEAD(&delayed_node->n_list);
  64	INIT_LIST_HEAD(&delayed_node->p_list);
  65	delayed_node->bytes_reserved = 0;
  66	memset(&delayed_node->inode_item, 0, sizeof(delayed_node->inode_item));
  67}
  68
  69static inline int btrfs_is_continuous_delayed_item(
  70					struct btrfs_delayed_item *item1,
  71					struct btrfs_delayed_item *item2)
  72{
  73	if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
  74	    item1->key.objectid == item2->key.objectid &&
  75	    item1->key.type == item2->key.type &&
  76	    item1->key.offset + 1 == item2->key.offset)
  77		return 1;
  78	return 0;
  79}
  80
  81static inline struct btrfs_delayed_root *btrfs_get_delayed_root(
  82							struct btrfs_root *root)
  83{
  84	return root->fs_info->delayed_root;
  85}
  86
  87static struct btrfs_delayed_node *btrfs_get_delayed_node(struct inode *inode)
  88{
  89	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
  90	struct btrfs_root *root = btrfs_inode->root;
  91	u64 ino = btrfs_ino(inode);
  92	struct btrfs_delayed_node *node;
  93
  94	node = ACCESS_ONCE(btrfs_inode->delayed_node);
  95	if (node) {
  96		atomic_inc(&node->refs);
  97		return node;
  98	}
  99
 100	spin_lock(&root->inode_lock);
 101	node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
 102	if (node) {
 103		if (btrfs_inode->delayed_node) {
 104			atomic_inc(&node->refs);	/* can be accessed */
 105			BUG_ON(btrfs_inode->delayed_node != node);
 106			spin_unlock(&root->inode_lock);
 107			return node;
 108		}
 109		btrfs_inode->delayed_node = node;
 110		/* can be accessed and cached in the inode */
 111		atomic_add(2, &node->refs);
 112		spin_unlock(&root->inode_lock);
 113		return node;
 114	}
 115	spin_unlock(&root->inode_lock);
 116
 117	return NULL;
 118}
 119
 120/* Will return either the node or PTR_ERR(-ENOMEM) */
 121static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 122							struct inode *inode)
 123{
 124	struct btrfs_delayed_node *node;
 125	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
 126	struct btrfs_root *root = btrfs_inode->root;
 127	u64 ino = btrfs_ino(inode);
 128	int ret;
 129
 130again:
 131	node = btrfs_get_delayed_node(inode);
 132	if (node)
 133		return node;
 134
 135	node = kmem_cache_alloc(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	atomic_add(2, &node->refs);
 142
 143	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
 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		kmem_cache_free(delayed_node_cache, node);
 153		spin_unlock(&root->inode_lock);
 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 */
 169static 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		atomic_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 */
 190static 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		atomic_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
 205static 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	atomic_inc(&node->refs);
 218out:
 219	spin_unlock(&delayed_root->lock);
 220
 221	return node;
 222}
 223
 224static 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	atomic_inc(&next->refs);
 245out:
 246	spin_unlock(&delayed_root->lock);
 247
 248	return next;
 249}
 250
 251static 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 (atomic_dec_and_test(&delayed_node->refs)) {
 270		struct btrfs_root *root = delayed_node->root;
 271		spin_lock(&root->inode_lock);
 272		if (atomic_read(&delayed_node->refs) == 0) {
 273			radix_tree_delete(&root->delayed_nodes_tree,
 274					  delayed_node->inode_id);
 275			kmem_cache_free(delayed_node_cache, delayed_node);
 276		}
 277		spin_unlock(&root->inode_lock);
 278	}
 279}
 280
 281static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 282{
 283	__btrfs_release_delayed_node(node, 0);
 284}
 285
 286static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 287					struct btrfs_delayed_root *delayed_root)
 288{
 289	struct list_head *p;
 290	struct btrfs_delayed_node *node = NULL;
 291
 292	spin_lock(&delayed_root->lock);
 293	if (list_empty(&delayed_root->prepare_list))
 294		goto out;
 295
 296	p = delayed_root->prepare_list.next;
 297	list_del_init(p);
 298	node = list_entry(p, struct btrfs_delayed_node, p_list);
 299	atomic_inc(&node->refs);
 300out:
 301	spin_unlock(&delayed_root->lock);
 302
 303	return node;
 304}
 305
 306static inline void btrfs_release_prepared_delayed_node(
 307					struct btrfs_delayed_node *node)
 308{
 309	__btrfs_release_delayed_node(node, 1);
 310}
 311
 312static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
 313{
 314	struct btrfs_delayed_item *item;
 315	item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
 316	if (item) {
 317		item->data_len = data_len;
 318		item->ins_or_del = 0;
 319		item->bytes_reserved = 0;
 320		item->delayed_node = NULL;
 321		atomic_set(&item->refs, 1);
 322	}
 323	return item;
 324}
 325
 326/*
 327 * __btrfs_lookup_delayed_item - look up the delayed item by key
 328 * @delayed_node: pointer to the delayed node
 329 * @key:	  the key to look up
 330 * @prev:	  used to store the prev item if the right item isn't found
 331 * @next:	  used to store the next item if the right item isn't found
 332 *
 333 * Note: if we don't find the right item, we will return the prev item and
 334 * the next item.
 335 */
 336static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 337				struct rb_root *root,
 338				struct btrfs_key *key,
 339				struct btrfs_delayed_item **prev,
 340				struct btrfs_delayed_item **next)
 341{
 342	struct rb_node *node, *prev_node = NULL;
 343	struct btrfs_delayed_item *delayed_item = NULL;
 344	int ret = 0;
 345
 346	node = root->rb_node;
 347
 348	while (node) {
 349		delayed_item = rb_entry(node, struct btrfs_delayed_item,
 350					rb_node);
 351		prev_node = node;
 352		ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
 353		if (ret < 0)
 354			node = node->rb_right;
 355		else if (ret > 0)
 356			node = node->rb_left;
 357		else
 358			return delayed_item;
 359	}
 360
 361	if (prev) {
 362		if (!prev_node)
 363			*prev = NULL;
 364		else if (ret < 0)
 365			*prev = delayed_item;
 366		else if ((node = rb_prev(prev_node)) != NULL) {
 367			*prev = rb_entry(node, struct btrfs_delayed_item,
 368					 rb_node);
 369		} else
 370			*prev = NULL;
 371	}
 372
 373	if (next) {
 374		if (!prev_node)
 375			*next = NULL;
 376		else if (ret > 0)
 377			*next = delayed_item;
 378		else if ((node = rb_next(prev_node)) != NULL) {
 379			*next = rb_entry(node, struct btrfs_delayed_item,
 380					 rb_node);
 381		} else
 382			*next = NULL;
 383	}
 384	return NULL;
 385}
 386
 387static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
 388					struct btrfs_delayed_node *delayed_node,
 389					struct btrfs_key *key)
 390{
 391	struct btrfs_delayed_item *item;
 392
 393	item = __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
 394					   NULL, NULL);
 395	return item;
 396}
 397
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 398static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 399				    struct btrfs_delayed_item *ins,
 400				    int action)
 401{
 402	struct rb_node **p, *node;
 403	struct rb_node *parent_node = NULL;
 404	struct rb_root *root;
 405	struct btrfs_delayed_item *item;
 406	int cmp;
 407
 408	if (action == BTRFS_DELAYED_INSERTION_ITEM)
 409		root = &delayed_node->ins_root;
 410	else if (action == BTRFS_DELAYED_DELETION_ITEM)
 411		root = &delayed_node->del_root;
 412	else
 413		BUG();
 414	p = &root->rb_node;
 415	node = &ins->rb_node;
 416
 417	while (*p) {
 418		parent_node = *p;
 419		item = rb_entry(parent_node, struct btrfs_delayed_item,
 420				 rb_node);
 421
 422		cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
 423		if (cmp < 0)
 424			p = &(*p)->rb_right;
 425		else if (cmp > 0)
 426			p = &(*p)->rb_left;
 427		else
 428			return -EEXIST;
 429	}
 430
 431	rb_link_node(node, parent_node, p);
 432	rb_insert_color(node, root);
 433	ins->delayed_node = delayed_node;
 434	ins->ins_or_del = action;
 435
 436	if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
 437	    action == BTRFS_DELAYED_INSERTION_ITEM &&
 438	    ins->key.offset >= delayed_node->index_cnt)
 439			delayed_node->index_cnt = ins->key.offset + 1;
 440
 441	delayed_node->count++;
 442	atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 443	return 0;
 444}
 445
 446static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
 447					      struct btrfs_delayed_item *item)
 448{
 449	return __btrfs_add_delayed_item(node, item,
 450					BTRFS_DELAYED_INSERTION_ITEM);
 451}
 452
 453static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 454					     struct btrfs_delayed_item *item)
 455{
 456	return __btrfs_add_delayed_item(node, item,
 457					BTRFS_DELAYED_DELETION_ITEM);
 458}
 459
 460static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 461{
 462	int seq = atomic_inc_return(&delayed_root->items_seq);
 463	if ((atomic_dec_return(&delayed_root->items) <
 464	    BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) &&
 465	    waitqueue_active(&delayed_root->wait))
 466		wake_up(&delayed_root->wait);
 467}
 468
 469static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 470{
 471	struct rb_root *root;
 472	struct btrfs_delayed_root *delayed_root;
 473
 474	delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
 475
 476	BUG_ON(!delayed_root);
 477	BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
 478	       delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
 479
 480	if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
 481		root = &delayed_item->delayed_node->ins_root;
 482	else
 483		root = &delayed_item->delayed_node->del_root;
 484
 485	rb_erase(&delayed_item->rb_node, root);
 486	delayed_item->delayed_node->count--;
 487
 488	finish_one_item(delayed_root);
 
 
 489}
 490
 491static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 492{
 493	if (item) {
 494		__btrfs_remove_delayed_item(item);
 495		if (atomic_dec_and_test(&item->refs))
 496			kfree(item);
 497	}
 498}
 499
 500static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
 501					struct btrfs_delayed_node *delayed_node)
 502{
 503	struct rb_node *p;
 504	struct btrfs_delayed_item *item = NULL;
 505
 506	p = rb_first(&delayed_node->ins_root);
 507	if (p)
 508		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 509
 510	return item;
 511}
 512
 513static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 514					struct btrfs_delayed_node *delayed_node)
 515{
 516	struct rb_node *p;
 517	struct btrfs_delayed_item *item = NULL;
 518
 519	p = rb_first(&delayed_node->del_root);
 520	if (p)
 521		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 522
 523	return item;
 524}
 525
 526static struct btrfs_delayed_item *__btrfs_next_delayed_item(
 527						struct btrfs_delayed_item *item)
 528{
 529	struct rb_node *p;
 530	struct btrfs_delayed_item *next = NULL;
 531
 532	p = rb_next(&item->rb_node);
 533	if (p)
 534		next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 535
 536	return next;
 537}
 538
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 539static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 540					       struct btrfs_root *root,
 541					       struct btrfs_delayed_item *item)
 542{
 543	struct btrfs_block_rsv *src_rsv;
 544	struct btrfs_block_rsv *dst_rsv;
 545	u64 num_bytes;
 546	int ret;
 547
 548	if (!trans->bytes_reserved)
 549		return 0;
 550
 551	src_rsv = trans->block_rsv;
 552	dst_rsv = &root->fs_info->delayed_block_rsv;
 553
 554	num_bytes = btrfs_calc_trans_metadata_size(root, 1);
 555	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
 556	if (!ret) {
 557		trace_btrfs_space_reservation(root->fs_info, "delayed_item",
 558					      item->key.objectid,
 559					      num_bytes, 1);
 560		item->bytes_reserved = num_bytes;
 561	}
 562
 563	return ret;
 564}
 565
 566static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
 567						struct btrfs_delayed_item *item)
 568{
 569	struct btrfs_block_rsv *rsv;
 570
 571	if (!item->bytes_reserved)
 572		return;
 573
 574	rsv = &root->fs_info->delayed_block_rsv;
 575	trace_btrfs_space_reservation(root->fs_info, "delayed_item",
 576				      item->key.objectid, item->bytes_reserved,
 577				      0);
 578	btrfs_block_rsv_release(root, rsv,
 579				item->bytes_reserved);
 580}
 581
 582static int btrfs_delayed_inode_reserve_metadata(
 583					struct btrfs_trans_handle *trans,
 584					struct btrfs_root *root,
 585					struct inode *inode,
 586					struct btrfs_delayed_node *node)
 587{
 588	struct btrfs_block_rsv *src_rsv;
 589	struct btrfs_block_rsv *dst_rsv;
 590	u64 num_bytes;
 591	int ret;
 592	bool release = false;
 
 
 593
 594	src_rsv = trans->block_rsv;
 595	dst_rsv = &root->fs_info->delayed_block_rsv;
 596
 597	num_bytes = btrfs_calc_trans_metadata_size(root, 1);
 598
 599	/*
 600	 * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 601	 * which doesn't reserve space for speed.  This is a problem since we
 602	 * still need to reserve space for this update, so try to reserve the
 603	 * space.
 604	 *
 605	 * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
 606	 * we're accounted for.
 607	 */
 608	if (!src_rsv || (!trans->bytes_reserved &&
 609			 src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
 610		ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 611					  BTRFS_RESERVE_NO_FLUSH);
 612		/*
 613		 * Since we're under a transaction reserve_metadata_bytes could
 614		 * try to commit the transaction which will make it return
 615		 * EAGAIN to make us stop the transaction we have, so return
 616		 * ENOSPC instead so that btrfs_dirty_inode knows what to do.
 617		 */
 618		if (ret == -EAGAIN)
 619			ret = -ENOSPC;
 620		if (!ret) {
 621			node->bytes_reserved = num_bytes;
 622			trace_btrfs_space_reservation(root->fs_info,
 623						      "delayed_inode",
 624						      btrfs_ino(inode),
 625						      num_bytes, 1);
 626		}
 627		return ret;
 628	} else if (src_rsv->type == BTRFS_BLOCK_RSV_DELALLOC) {
 629		spin_lock(&BTRFS_I(inode)->lock);
 630		if (test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
 631				       &BTRFS_I(inode)->runtime_flags)) {
 632			spin_unlock(&BTRFS_I(inode)->lock);
 633			release = true;
 634			goto migrate;
 635		}
 636		spin_unlock(&BTRFS_I(inode)->lock);
 637
 638		/* Ok we didn't have space pre-reserved.  This shouldn't happen
 639		 * too often but it can happen if we do delalloc to an existing
 640		 * inode which gets dirtied because of the time update, and then
 641		 * isn't touched again until after the transaction commits and
 642		 * then we try to write out the data.  First try to be nice and
 643		 * reserve something strictly for us.  If not be a pain and try
 644		 * to steal from the delalloc block rsv.
 645		 */
 646		ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 647					  BTRFS_RESERVE_NO_FLUSH);
 648		if (!ret)
 649			goto out;
 650
 651		ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
 652		if (!WARN_ON(ret))
 653			goto out;
 654
 655		/*
 656		 * Ok this is a problem, let's just steal from the global rsv
 657		 * since this really shouldn't happen that often.
 658		 */
 659		ret = btrfs_block_rsv_migrate(&root->fs_info->global_block_rsv,
 660					      dst_rsv, num_bytes);
 661		goto out;
 662	}
 663
 664migrate:
 665	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
 666
 667out:
 668	/*
 669	 * Migrate only takes a reservation, it doesn't touch the size of the
 670	 * block_rsv.  This is to simplify people who don't normally have things
 671	 * migrated from their block rsv.  If they go to release their
 672	 * reservation, that will decrease the size as well, so if migrate
 673	 * reduced size we'd end up with a negative size.  But for the
 674	 * delalloc_meta_reserved stuff we will only know to drop 1 reservation,
 675	 * but we could in fact do this reserve/migrate dance several times
 676	 * between the time we did the original reservation and we'd clean it
 677	 * up.  So to take care of this, release the space for the meta
 678	 * reservation here.  I think it may be time for a documentation page on
 679	 * how block rsvs. work.
 680	 */
 681	if (!ret) {
 682		trace_btrfs_space_reservation(root->fs_info, "delayed_inode",
 683					      btrfs_ino(inode), num_bytes, 1);
 684		node->bytes_reserved = num_bytes;
 685	}
 686
 687	if (release) {
 688		trace_btrfs_space_reservation(root->fs_info, "delalloc",
 689					      btrfs_ino(inode), num_bytes, 0);
 690		btrfs_block_rsv_release(root, src_rsv, num_bytes);
 691	}
 692
 693	return ret;
 694}
 695
 696static void btrfs_delayed_inode_release_metadata(struct btrfs_root *root,
 697						struct btrfs_delayed_node *node)
 698{
 699	struct btrfs_block_rsv *rsv;
 700
 701	if (!node->bytes_reserved)
 702		return;
 703
 704	rsv = &root->fs_info->delayed_block_rsv;
 705	trace_btrfs_space_reservation(root->fs_info, "delayed_inode",
 706				      node->inode_id, node->bytes_reserved, 0);
 707	btrfs_block_rsv_release(root, rsv,
 708				node->bytes_reserved);
 709	node->bytes_reserved = 0;
 710}
 711
 712/*
 713 * This helper will insert some continuous items into the same leaf according
 714 * to the free space of the leaf.
 715 */
 716static int btrfs_batch_insert_items(struct btrfs_root *root,
 717				    struct btrfs_path *path,
 718				    struct btrfs_delayed_item *item)
 
 719{
 720	struct btrfs_delayed_item *curr, *next;
 721	int free_space;
 722	int total_data_size = 0, total_size = 0;
 723	struct extent_buffer *leaf;
 724	char *data_ptr;
 725	struct btrfs_key *keys;
 726	u32 *data_size;
 727	struct list_head head;
 728	int slot;
 729	int nitems;
 730	int i;
 731	int ret = 0;
 732
 733	BUG_ON(!path->nodes[0]);
 734
 735	leaf = path->nodes[0];
 736	free_space = btrfs_leaf_free_space(root, leaf);
 737	INIT_LIST_HEAD(&head);
 738
 739	next = item;
 740	nitems = 0;
 741
 742	/*
 743	 * count the number of the continuous items that we can insert in batch
 744	 */
 745	while (total_size + next->data_len + sizeof(struct btrfs_item) <=
 746	       free_space) {
 747		total_data_size += next->data_len;
 748		total_size += next->data_len + sizeof(struct btrfs_item);
 749		list_add_tail(&next->tree_list, &head);
 750		nitems++;
 751
 752		curr = next;
 753		next = __btrfs_next_delayed_item(curr);
 754		if (!next)
 755			break;
 756
 757		if (!btrfs_is_continuous_delayed_item(curr, next))
 758			break;
 759	}
 760
 761	if (!nitems) {
 762		ret = 0;
 763		goto out;
 764	}
 765
 766	/*
 767	 * we need allocate some memory space, but it might cause the task
 768	 * to sleep, so we set all locked nodes in the path to blocking locks
 769	 * first.
 770	 */
 771	btrfs_set_path_blocking(path);
 772
 773	keys = kmalloc_array(nitems, sizeof(struct btrfs_key), GFP_NOFS);
 774	if (!keys) {
 775		ret = -ENOMEM;
 776		goto out;
 777	}
 778
 779	data_size = kmalloc_array(nitems, sizeof(u32), GFP_NOFS);
 780	if (!data_size) {
 781		ret = -ENOMEM;
 782		goto error;
 783	}
 784
 785	/* get keys of all the delayed items */
 786	i = 0;
 787	list_for_each_entry(next, &head, tree_list) {
 788		keys[i] = next->key;
 789		data_size[i] = next->data_len;
 790		i++;
 791	}
 792
 793	/* reset all the locked nodes in the patch to spinning locks. */
 794	btrfs_clear_path_blocking(path, NULL, 0);
 795
 796	/* insert the keys of the items */
 797	setup_items_for_insert(root, path, keys, data_size,
 798			       total_data_size, total_size, nitems);
 
 
 799
 800	/* insert the dir index items */
 801	slot = path->slots[0];
 802	list_for_each_entry_safe(curr, next, &head, tree_list) {
 803		data_ptr = btrfs_item_ptr(leaf, slot, char);
 804		write_extent_buffer(leaf, &curr->data,
 805				    (unsigned long)data_ptr,
 806				    curr->data_len);
 807		slot++;
 808
 809		btrfs_delayed_item_release_metadata(root, curr);
 810
 811		list_del(&curr->tree_list);
 812		btrfs_release_delayed_item(curr);
 813	}
 814
 815error:
 816	kfree(data_size);
 817	kfree(keys);
 818out:
 819	return ret;
 820}
 821
 822/*
 823 * This helper can just do simple insertion that needn't extend item for new
 824 * data, such as directory name index insertion, inode insertion.
 825 */
 826static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 827				     struct btrfs_root *root,
 828				     struct btrfs_path *path,
 829				     struct btrfs_delayed_item *delayed_item)
 830{
 831	struct extent_buffer *leaf;
 
 832	char *ptr;
 833	int ret;
 834
 835	ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
 836				      delayed_item->data_len);
 837	if (ret < 0 && ret != -EEXIST)
 838		return ret;
 839
 840	leaf = path->nodes[0];
 841
 
 842	ptr = btrfs_item_ptr(leaf, path->slots[0], char);
 843
 844	write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
 845			    delayed_item->data_len);
 846	btrfs_mark_buffer_dirty(leaf);
 847
 848	btrfs_delayed_item_release_metadata(root, delayed_item);
 849	return 0;
 850}
 851
 852/*
 853 * we insert an item first, then if there are some continuous items, we try
 854 * to insert those items into the same leaf.
 855 */
 856static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 857				      struct btrfs_path *path,
 858				      struct btrfs_root *root,
 859				      struct btrfs_delayed_node *node)
 860{
 861	struct btrfs_delayed_item *curr, *prev;
 862	int ret = 0;
 863
 864do_again:
 865	mutex_lock(&node->mutex);
 866	curr = __btrfs_first_delayed_insertion_item(node);
 867	if (!curr)
 868		goto insert_end;
 869
 870	ret = btrfs_insert_delayed_item(trans, root, path, curr);
 871	if (ret < 0) {
 872		btrfs_release_path(path);
 873		goto insert_end;
 874	}
 875
 876	prev = curr;
 877	curr = __btrfs_next_delayed_item(prev);
 878	if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
 879		/* insert the continuous items into the same leaf */
 880		path->slots[0]++;
 881		btrfs_batch_insert_items(root, path, curr);
 882	}
 883	btrfs_release_delayed_item(prev);
 884	btrfs_mark_buffer_dirty(path->nodes[0]);
 885
 886	btrfs_release_path(path);
 887	mutex_unlock(&node->mutex);
 888	goto do_again;
 889
 890insert_end:
 891	mutex_unlock(&node->mutex);
 892	return ret;
 893}
 894
 895static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
 896				    struct btrfs_root *root,
 897				    struct btrfs_path *path,
 898				    struct btrfs_delayed_item *item)
 899{
 900	struct btrfs_delayed_item *curr, *next;
 901	struct extent_buffer *leaf;
 902	struct btrfs_key key;
 903	struct list_head head;
 904	int nitems, i, last_item;
 905	int ret = 0;
 906
 907	BUG_ON(!path->nodes[0]);
 908
 909	leaf = path->nodes[0];
 910
 911	i = path->slots[0];
 912	last_item = btrfs_header_nritems(leaf) - 1;
 913	if (i > last_item)
 914		return -ENOENT;	/* FIXME: Is errno suitable? */
 915
 916	next = item;
 917	INIT_LIST_HEAD(&head);
 918	btrfs_item_key_to_cpu(leaf, &key, i);
 919	nitems = 0;
 920	/*
 921	 * count the number of the dir index items that we can delete in batch
 922	 */
 923	while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
 924		list_add_tail(&next->tree_list, &head);
 925		nitems++;
 926
 927		curr = next;
 928		next = __btrfs_next_delayed_item(curr);
 929		if (!next)
 930			break;
 931
 932		if (!btrfs_is_continuous_delayed_item(curr, next))
 933			break;
 934
 935		i++;
 936		if (i > last_item)
 937			break;
 938		btrfs_item_key_to_cpu(leaf, &key, i);
 939	}
 940
 941	if (!nitems)
 942		return 0;
 943
 944	ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 945	if (ret)
 946		goto out;
 947
 948	list_for_each_entry_safe(curr, next, &head, tree_list) {
 949		btrfs_delayed_item_release_metadata(root, curr);
 950		list_del(&curr->tree_list);
 951		btrfs_release_delayed_item(curr);
 952	}
 953
 954out:
 955	return ret;
 956}
 957
 958static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 959				      struct btrfs_path *path,
 960				      struct btrfs_root *root,
 961				      struct btrfs_delayed_node *node)
 962{
 963	struct btrfs_delayed_item *curr, *prev;
 964	int ret = 0;
 965
 966do_again:
 967	mutex_lock(&node->mutex);
 968	curr = __btrfs_first_delayed_deletion_item(node);
 969	if (!curr)
 970		goto delete_fail;
 971
 972	ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
 973	if (ret < 0)
 974		goto delete_fail;
 975	else if (ret > 0) {
 976		/*
 977		 * can't find the item which the node points to, so this node
 978		 * is invalid, just drop it.
 979		 */
 980		prev = curr;
 981		curr = __btrfs_next_delayed_item(prev);
 982		btrfs_release_delayed_item(prev);
 983		ret = 0;
 984		btrfs_release_path(path);
 985		if (curr) {
 986			mutex_unlock(&node->mutex);
 987			goto do_again;
 988		} else
 989			goto delete_fail;
 990	}
 991
 992	btrfs_batch_delete_items(trans, root, path, curr);
 993	btrfs_release_path(path);
 994	mutex_unlock(&node->mutex);
 995	goto do_again;
 996
 997delete_fail:
 998	btrfs_release_path(path);
 999	mutex_unlock(&node->mutex);
1000	return ret;
1001}
1002
1003static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
1004{
1005	struct btrfs_delayed_root *delayed_root;
1006
1007	if (delayed_node &&
1008	    test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1009		BUG_ON(!delayed_node->root);
1010		clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1011		delayed_node->count--;
1012
1013		delayed_root = delayed_node->root->fs_info->delayed_root;
1014		finish_one_item(delayed_root);
 
 
 
 
1015	}
1016}
1017
1018static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
1019{
1020	struct btrfs_delayed_root *delayed_root;
1021
1022	ASSERT(delayed_node->root);
1023	clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1024	delayed_node->count--;
1025
1026	delayed_root = delayed_node->root->fs_info->delayed_root;
1027	finish_one_item(delayed_root);
1028}
1029
1030static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1031					struct btrfs_root *root,
1032					struct btrfs_path *path,
1033					struct btrfs_delayed_node *node)
1034{
1035	struct btrfs_key key;
1036	struct btrfs_inode_item *inode_item;
1037	struct extent_buffer *leaf;
1038	int mod;
1039	int ret;
1040
 
 
 
 
 
 
1041	key.objectid = node->inode_id;
1042	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1043	key.offset = 0;
1044
1045	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1046		mod = -1;
1047	else
1048		mod = 1;
1049
1050	ret = btrfs_lookup_inode(trans, root, path, &key, mod);
1051	if (ret > 0) {
1052		btrfs_release_path(path);
 
1053		return -ENOENT;
1054	} else if (ret < 0) {
 
1055		return ret;
1056	}
1057
 
1058	leaf = path->nodes[0];
1059	inode_item = btrfs_item_ptr(leaf, path->slots[0],
1060				    struct btrfs_inode_item);
1061	write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1062			    sizeof(struct btrfs_inode_item));
1063	btrfs_mark_buffer_dirty(leaf);
 
1064
1065	if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1066		goto no_iref;
1067
1068	path->slots[0]++;
1069	if (path->slots[0] >= btrfs_header_nritems(leaf))
1070		goto search;
1071again:
1072	btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1073	if (key.objectid != node->inode_id)
1074		goto out;
1075
1076	if (key.type != BTRFS_INODE_REF_KEY &&
1077	    key.type != BTRFS_INODE_EXTREF_KEY)
1078		goto out;
1079
1080	/*
1081	 * Delayed iref deletion is for the inode who has only one link,
1082	 * so there is only one iref. The case that several irefs are
1083	 * in the same item doesn't exist.
1084	 */
1085	btrfs_del_item(trans, root, path);
1086out:
1087	btrfs_release_delayed_iref(node);
1088no_iref:
1089	btrfs_release_path(path);
1090err_out:
1091	btrfs_delayed_inode_release_metadata(root, node);
1092	btrfs_release_delayed_inode(node);
1093
1094	return ret;
1095
1096search:
1097	btrfs_release_path(path);
1098
1099	btrfs_set_key_type(&key, BTRFS_INODE_EXTREF_KEY);
1100	key.offset = -1;
1101	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1102	if (ret < 0)
1103		goto err_out;
1104	ASSERT(ret);
1105
1106	ret = 0;
1107	leaf = path->nodes[0];
1108	path->slots[0]--;
1109	goto again;
1110}
1111
1112static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1113					     struct btrfs_root *root,
1114					     struct btrfs_path *path,
1115					     struct btrfs_delayed_node *node)
1116{
1117	int ret;
1118
1119	mutex_lock(&node->mutex);
1120	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
1121		mutex_unlock(&node->mutex);
1122		return 0;
1123	}
1124
1125	ret = __btrfs_update_delayed_inode(trans, root, path, node);
1126	mutex_unlock(&node->mutex);
1127	return ret;
1128}
1129
1130static inline int
1131__btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1132				   struct btrfs_path *path,
1133				   struct btrfs_delayed_node *node)
1134{
1135	int ret;
1136
1137	ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1138	if (ret)
1139		return ret;
1140
1141	ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1142	if (ret)
1143		return ret;
1144
1145	ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1146	return ret;
1147}
1148
1149/*
1150 * Called when committing the transaction.
1151 * Returns 0 on success.
1152 * Returns < 0 on error and returns with an aborted transaction with any
1153 * outstanding delayed items cleaned up.
1154 */
1155static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1156				     struct btrfs_root *root, int nr)
1157{
1158	struct btrfs_delayed_root *delayed_root;
1159	struct btrfs_delayed_node *curr_node, *prev_node;
1160	struct btrfs_path *path;
1161	struct btrfs_block_rsv *block_rsv;
1162	int ret = 0;
1163	bool count = (nr > 0);
1164
1165	if (trans->aborted)
1166		return -EIO;
1167
1168	path = btrfs_alloc_path();
1169	if (!path)
1170		return -ENOMEM;
1171	path->leave_spinning = 1;
1172
1173	block_rsv = trans->block_rsv;
1174	trans->block_rsv = &root->fs_info->delayed_block_rsv;
1175
1176	delayed_root = btrfs_get_delayed_root(root);
1177
1178	curr_node = btrfs_first_delayed_node(delayed_root);
1179	while (curr_node && (!count || (count && nr--))) {
1180		ret = __btrfs_commit_inode_delayed_items(trans, path,
 
 
 
 
 
 
 
1181							 curr_node);
1182		if (ret) {
1183			btrfs_release_delayed_node(curr_node);
1184			curr_node = NULL;
1185			btrfs_abort_transaction(trans, root, ret);
1186			break;
1187		}
1188
1189		prev_node = curr_node;
1190		curr_node = btrfs_next_delayed_node(curr_node);
1191		btrfs_release_delayed_node(prev_node);
1192	}
1193
1194	if (curr_node)
1195		btrfs_release_delayed_node(curr_node);
1196	btrfs_free_path(path);
1197	trans->block_rsv = block_rsv;
1198
1199	return ret;
1200}
1201
1202int btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1203			    struct btrfs_root *root)
1204{
1205	return __btrfs_run_delayed_items(trans, root, -1);
1206}
1207
1208int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans,
1209			       struct btrfs_root *root, int nr)
1210{
1211	return __btrfs_run_delayed_items(trans, root, nr);
1212}
1213
1214int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1215				     struct inode *inode)
1216{
1217	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1218	struct btrfs_path *path;
1219	struct btrfs_block_rsv *block_rsv;
1220	int ret;
1221
1222	if (!delayed_node)
1223		return 0;
1224
1225	mutex_lock(&delayed_node->mutex);
1226	if (!delayed_node->count) {
1227		mutex_unlock(&delayed_node->mutex);
1228		btrfs_release_delayed_node(delayed_node);
1229		return 0;
1230	}
1231	mutex_unlock(&delayed_node->mutex);
1232
1233	path = btrfs_alloc_path();
1234	if (!path) {
1235		btrfs_release_delayed_node(delayed_node);
1236		return -ENOMEM;
1237	}
1238	path->leave_spinning = 1;
1239
1240	block_rsv = trans->block_rsv;
1241	trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1242
1243	ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
 
 
 
 
 
1244
1245	btrfs_release_delayed_node(delayed_node);
1246	btrfs_free_path(path);
1247	trans->block_rsv = block_rsv;
1248
1249	return ret;
1250}
1251
1252int btrfs_commit_inode_delayed_inode(struct inode *inode)
 
1253{
1254	struct btrfs_trans_handle *trans;
1255	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1256	struct btrfs_path *path;
1257	struct btrfs_block_rsv *block_rsv;
1258	int ret;
1259
1260	if (!delayed_node)
1261		return 0;
1262
1263	mutex_lock(&delayed_node->mutex);
1264	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1265		mutex_unlock(&delayed_node->mutex);
1266		btrfs_release_delayed_node(delayed_node);
1267		return 0;
1268	}
1269	mutex_unlock(&delayed_node->mutex);
1270
1271	trans = btrfs_join_transaction(delayed_node->root);
1272	if (IS_ERR(trans)) {
1273		ret = PTR_ERR(trans);
1274		goto out;
1275	}
1276
1277	path = btrfs_alloc_path();
1278	if (!path) {
1279		ret = -ENOMEM;
1280		goto trans_out;
1281	}
1282	path->leave_spinning = 1;
1283
1284	block_rsv = trans->block_rsv;
1285	trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1286
1287	mutex_lock(&delayed_node->mutex);
1288	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
1289		ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1290						   path, delayed_node);
1291	else
1292		ret = 0;
1293	mutex_unlock(&delayed_node->mutex);
1294
1295	btrfs_free_path(path);
1296	trans->block_rsv = block_rsv;
1297trans_out:
1298	btrfs_end_transaction(trans, delayed_node->root);
1299	btrfs_btree_balance_dirty(delayed_node->root);
1300out:
1301	btrfs_release_delayed_node(delayed_node);
1302
1303	return ret;
1304}
1305
1306void btrfs_remove_delayed_node(struct inode *inode)
1307{
1308	struct btrfs_delayed_node *delayed_node;
1309
1310	delayed_node = ACCESS_ONCE(BTRFS_I(inode)->delayed_node);
1311	if (!delayed_node)
1312		return;
1313
1314	BTRFS_I(inode)->delayed_node = NULL;
1315	btrfs_release_delayed_node(delayed_node);
1316}
1317
1318struct btrfs_async_delayed_work {
1319	struct btrfs_delayed_root *delayed_root;
1320	int nr;
1321	struct btrfs_work work;
1322};
1323
1324static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1325{
1326	struct btrfs_async_delayed_work *async_work;
1327	struct btrfs_delayed_root *delayed_root;
1328	struct btrfs_trans_handle *trans;
1329	struct btrfs_path *path;
1330	struct btrfs_delayed_node *delayed_node = NULL;
1331	struct btrfs_root *root;
1332	struct btrfs_block_rsv *block_rsv;
1333	int total_done = 0;
 
 
1334
1335	async_work = container_of(work, struct btrfs_async_delayed_work, work);
1336	delayed_root = async_work->delayed_root;
1337
1338	path = btrfs_alloc_path();
1339	if (!path)
1340		goto out;
 
1341
1342again:
1343	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND / 2)
1344		goto free_path;
1345
1346	delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1347	if (!delayed_node)
1348		goto free_path;
1349
1350	path->leave_spinning = 1;
1351	root = delayed_node->root;
1352
1353	trans = btrfs_join_transaction(root);
1354	if (IS_ERR(trans))
1355		goto release_path;
1356
1357	block_rsv = trans->block_rsv;
1358	trans->block_rsv = &root->fs_info->delayed_block_rsv;
1359
1360	__btrfs_commit_inode_delayed_items(trans, path, delayed_node);
 
 
 
1361
1362	trans->block_rsv = block_rsv;
1363	btrfs_end_transaction(trans, root);
1364	btrfs_btree_balance_dirty_nodelay(root);
1365
1366release_path:
1367	btrfs_release_path(path);
1368	total_done++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1369
1370	btrfs_release_prepared_delayed_node(delayed_node);
1371	if (async_work->nr == 0 || total_done < async_work->nr)
1372		goto again;
1373
 
 
 
1374free_path:
1375	btrfs_free_path(path);
1376out:
1377	wake_up(&delayed_root->wait);
1378	kfree(async_work);
 
 
 
 
1379}
1380
1381
1382static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1383				     struct btrfs_root *root, int nr)
1384{
1385	struct btrfs_async_delayed_work *async_work;
 
 
1386
1387	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
 
 
1388		return 0;
1389
1390	async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
1391	if (!async_work)
 
1392		return -ENOMEM;
 
 
 
 
 
 
 
1393
1394	async_work->delayed_root = delayed_root;
1395	btrfs_init_work(&async_work->work, btrfs_async_run_delayed_root,
1396			NULL, NULL);
1397	async_work->nr = nr;
 
1398
1399	btrfs_queue_work(root->fs_info->delayed_workers, &async_work->work);
1400	return 0;
1401}
1402
1403void btrfs_assert_delayed_root_empty(struct btrfs_root *root)
1404{
1405	struct btrfs_delayed_root *delayed_root;
1406	delayed_root = btrfs_get_delayed_root(root);
1407	WARN_ON(btrfs_first_delayed_node(delayed_root));
1408}
1409
1410static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
1411{
1412	int val = atomic_read(&delayed_root->items_seq);
1413
1414	if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
1415		return 1;
1416
1417	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1418		return 1;
1419
1420	return 0;
1421}
1422
1423void btrfs_balance_delayed_items(struct btrfs_root *root)
1424{
1425	struct btrfs_delayed_root *delayed_root;
1426
1427	delayed_root = btrfs_get_delayed_root(root);
1428
1429	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1430		return;
1431
1432	if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1433		int seq;
1434		int ret;
1435
1436		seq = atomic_read(&delayed_root->items_seq);
1437
1438		ret = btrfs_wq_run_delayed_node(delayed_root, root, 0);
1439		if (ret)
1440			return;
1441
1442		wait_event_interruptible(delayed_root->wait,
1443					 could_end_wait(delayed_root, seq));
 
 
 
1444		return;
1445	}
1446
1447	btrfs_wq_run_delayed_node(delayed_root, root, BTRFS_DELAYED_BATCH);
1448}
1449
1450/* Will return 0 or -ENOMEM */
1451int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1452				   struct btrfs_root *root, const char *name,
1453				   int name_len, struct inode *dir,
1454				   struct btrfs_disk_key *disk_key, u8 type,
1455				   u64 index)
1456{
1457	struct btrfs_delayed_node *delayed_node;
1458	struct btrfs_delayed_item *delayed_item;
1459	struct btrfs_dir_item *dir_item;
1460	int ret;
1461
1462	delayed_node = btrfs_get_or_create_delayed_node(dir);
1463	if (IS_ERR(delayed_node))
1464		return PTR_ERR(delayed_node);
1465
1466	delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
1467	if (!delayed_item) {
1468		ret = -ENOMEM;
1469		goto release_node;
1470	}
1471
 
 
 
 
 
 
 
1472	delayed_item->key.objectid = btrfs_ino(dir);
1473	btrfs_set_key_type(&delayed_item->key, BTRFS_DIR_INDEX_KEY);
1474	delayed_item->key.offset = index;
1475
1476	dir_item = (struct btrfs_dir_item *)delayed_item->data;
1477	dir_item->location = *disk_key;
1478	btrfs_set_stack_dir_transid(dir_item, trans->transid);
1479	btrfs_set_stack_dir_data_len(dir_item, 0);
1480	btrfs_set_stack_dir_name_len(dir_item, name_len);
1481	btrfs_set_stack_dir_type(dir_item, type);
1482	memcpy((char *)(dir_item + 1), name, name_len);
1483
1484	ret = btrfs_delayed_item_reserve_metadata(trans, root, delayed_item);
1485	/*
1486	 * we have reserved enough space when we start a new transaction,
1487	 * so reserving metadata failure is impossible
1488	 */
1489	BUG_ON(ret);
1490
1491
1492	mutex_lock(&delayed_node->mutex);
1493	ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1494	if (unlikely(ret)) {
1495		btrfs_err(root->fs_info, "err add delayed dir index item(name: %.*s) "
1496				"into the insertion tree of the delayed node"
1497				"(root id: %llu, inode id: %llu, errno: %d)",
1498				name_len, name, delayed_node->root->objectid,
1499				delayed_node->inode_id, ret);
 
 
1500		BUG();
1501	}
1502	mutex_unlock(&delayed_node->mutex);
1503
1504release_node:
1505	btrfs_release_delayed_node(delayed_node);
1506	return ret;
1507}
1508
1509static int btrfs_delete_delayed_insertion_item(struct btrfs_root *root,
1510					       struct btrfs_delayed_node *node,
1511					       struct btrfs_key *key)
1512{
1513	struct btrfs_delayed_item *item;
1514
1515	mutex_lock(&node->mutex);
1516	item = __btrfs_lookup_delayed_insertion_item(node, key);
1517	if (!item) {
1518		mutex_unlock(&node->mutex);
1519		return 1;
1520	}
1521
1522	btrfs_delayed_item_release_metadata(root, item);
1523	btrfs_release_delayed_item(item);
1524	mutex_unlock(&node->mutex);
1525	return 0;
1526}
1527
1528int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1529				   struct btrfs_root *root, struct inode *dir,
1530				   u64 index)
1531{
1532	struct btrfs_delayed_node *node;
1533	struct btrfs_delayed_item *item;
1534	struct btrfs_key item_key;
1535	int ret;
1536
1537	node = btrfs_get_or_create_delayed_node(dir);
1538	if (IS_ERR(node))
1539		return PTR_ERR(node);
1540
1541	item_key.objectid = btrfs_ino(dir);
1542	btrfs_set_key_type(&item_key, BTRFS_DIR_INDEX_KEY);
1543	item_key.offset = index;
1544
1545	ret = btrfs_delete_delayed_insertion_item(root, node, &item_key);
1546	if (!ret)
1547		goto end;
1548
1549	item = btrfs_alloc_delayed_item(0);
1550	if (!item) {
1551		ret = -ENOMEM;
1552		goto end;
1553	}
1554
1555	item->key = item_key;
1556
1557	ret = btrfs_delayed_item_reserve_metadata(trans, root, item);
1558	/*
1559	 * we have reserved enough space when we start a new transaction,
1560	 * so reserving metadata failure is impossible.
1561	 */
1562	BUG_ON(ret);
1563
1564	mutex_lock(&node->mutex);
1565	ret = __btrfs_add_delayed_deletion_item(node, item);
1566	if (unlikely(ret)) {
1567		btrfs_err(root->fs_info, "err add delayed dir index item(index: %llu) "
1568				"into the deletion tree of the delayed node"
1569				"(root id: %llu, inode id: %llu, errno: %d)",
1570				index, node->root->objectid, node->inode_id,
 
 
1571				ret);
1572		BUG();
1573	}
1574	mutex_unlock(&node->mutex);
1575end:
1576	btrfs_release_delayed_node(node);
1577	return ret;
1578}
1579
1580int btrfs_inode_delayed_dir_index_count(struct inode *inode)
1581{
1582	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1583
1584	if (!delayed_node)
1585		return -ENOENT;
1586
1587	/*
1588	 * Since we have held i_mutex of this directory, it is impossible that
1589	 * a new directory index is added into the delayed node and index_cnt
1590	 * is updated now. So we needn't lock the delayed node.
1591	 */
1592	if (!delayed_node->index_cnt) {
1593		btrfs_release_delayed_node(delayed_node);
1594		return -EINVAL;
1595	}
1596
1597	BTRFS_I(inode)->index_cnt = delayed_node->index_cnt;
1598	btrfs_release_delayed_node(delayed_node);
1599	return 0;
1600}
1601
1602void btrfs_get_delayed_items(struct inode *inode, struct list_head *ins_list,
1603			     struct list_head *del_list)
1604{
1605	struct btrfs_delayed_node *delayed_node;
1606	struct btrfs_delayed_item *item;
1607
1608	delayed_node = btrfs_get_delayed_node(inode);
1609	if (!delayed_node)
1610		return;
1611
1612	mutex_lock(&delayed_node->mutex);
1613	item = __btrfs_first_delayed_insertion_item(delayed_node);
1614	while (item) {
1615		atomic_inc(&item->refs);
1616		list_add_tail(&item->readdir_list, ins_list);
1617		item = __btrfs_next_delayed_item(item);
1618	}
1619
1620	item = __btrfs_first_delayed_deletion_item(delayed_node);
1621	while (item) {
1622		atomic_inc(&item->refs);
1623		list_add_tail(&item->readdir_list, del_list);
1624		item = __btrfs_next_delayed_item(item);
1625	}
1626	mutex_unlock(&delayed_node->mutex);
1627	/*
1628	 * This delayed node is still cached in the btrfs inode, so refs
1629	 * must be > 1 now, and we needn't check it is going to be freed
1630	 * or not.
1631	 *
1632	 * Besides that, this function is used to read dir, we do not
1633	 * insert/delete delayed items in this period. So we also needn't
1634	 * requeue or dequeue this delayed node.
1635	 */
1636	atomic_dec(&delayed_node->refs);
1637}
1638
1639void btrfs_put_delayed_items(struct list_head *ins_list,
1640			     struct list_head *del_list)
1641{
1642	struct btrfs_delayed_item *curr, *next;
1643
1644	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1645		list_del(&curr->readdir_list);
1646		if (atomic_dec_and_test(&curr->refs))
1647			kfree(curr);
1648	}
1649
1650	list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1651		list_del(&curr->readdir_list);
1652		if (atomic_dec_and_test(&curr->refs))
1653			kfree(curr);
1654	}
1655}
1656
1657int btrfs_should_delete_dir_index(struct list_head *del_list,
1658				  u64 index)
1659{
1660	struct btrfs_delayed_item *curr, *next;
1661	int ret;
1662
1663	if (list_empty(del_list))
1664		return 0;
1665
1666	list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1667		if (curr->key.offset > index)
1668			break;
1669
1670		list_del(&curr->readdir_list);
1671		ret = (curr->key.offset == index);
1672
1673		if (atomic_dec_and_test(&curr->refs))
1674			kfree(curr);
1675
1676		if (ret)
1677			return 1;
1678		else
1679			continue;
1680	}
1681	return 0;
1682}
1683
1684/*
1685 * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1686 *
1687 */
1688int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
 
1689				    struct list_head *ins_list)
1690{
1691	struct btrfs_dir_item *di;
1692	struct btrfs_delayed_item *curr, *next;
1693	struct btrfs_key location;
1694	char *name;
1695	int name_len;
1696	int over = 0;
1697	unsigned char d_type;
1698
1699	if (list_empty(ins_list))
1700		return 0;
1701
1702	/*
1703	 * Changing the data of the delayed item is impossible. So
1704	 * we needn't lock them. And we have held i_mutex of the
1705	 * directory, nobody can delete any directory indexes now.
1706	 */
1707	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1708		list_del(&curr->readdir_list);
1709
1710		if (curr->key.offset < ctx->pos) {
1711			if (atomic_dec_and_test(&curr->refs))
1712				kfree(curr);
1713			continue;
1714		}
1715
1716		ctx->pos = curr->key.offset;
1717
1718		di = (struct btrfs_dir_item *)curr->data;
1719		name = (char *)(di + 1);
1720		name_len = btrfs_stack_dir_name_len(di);
1721
1722		d_type = btrfs_filetype_table[di->type];
1723		btrfs_disk_key_to_cpu(&location, &di->location);
1724
1725		over = !dir_emit(ctx, name, name_len,
1726			       location.objectid, d_type);
1727
1728		if (atomic_dec_and_test(&curr->refs))
1729			kfree(curr);
1730
1731		if (over)
1732			return 1;
1733	}
1734	return 0;
1735}
1736
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1737static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1738				  struct btrfs_inode_item *inode_item,
1739				  struct inode *inode)
1740{
1741	btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1742	btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1743	btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1744	btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1745	btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1746	btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1747	btrfs_set_stack_inode_generation(inode_item,
1748					 BTRFS_I(inode)->generation);
1749	btrfs_set_stack_inode_sequence(inode_item, inode->i_version);
1750	btrfs_set_stack_inode_transid(inode_item, trans->transid);
1751	btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1752	btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
1753	btrfs_set_stack_inode_block_group(inode_item, 0);
1754
1755	btrfs_set_stack_timespec_sec(btrfs_inode_atime(inode_item),
1756				     inode->i_atime.tv_sec);
1757	btrfs_set_stack_timespec_nsec(btrfs_inode_atime(inode_item),
1758				      inode->i_atime.tv_nsec);
1759
1760	btrfs_set_stack_timespec_sec(btrfs_inode_mtime(inode_item),
1761				     inode->i_mtime.tv_sec);
1762	btrfs_set_stack_timespec_nsec(btrfs_inode_mtime(inode_item),
1763				      inode->i_mtime.tv_nsec);
1764
1765	btrfs_set_stack_timespec_sec(btrfs_inode_ctime(inode_item),
1766				     inode->i_ctime.tv_sec);
1767	btrfs_set_stack_timespec_nsec(btrfs_inode_ctime(inode_item),
1768				      inode->i_ctime.tv_nsec);
1769}
1770
1771int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1772{
1773	struct btrfs_delayed_node *delayed_node;
1774	struct btrfs_inode_item *inode_item;
1775	struct btrfs_timespec *tspec;
1776
1777	delayed_node = btrfs_get_delayed_node(inode);
1778	if (!delayed_node)
1779		return -ENOENT;
1780
1781	mutex_lock(&delayed_node->mutex);
1782	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1783		mutex_unlock(&delayed_node->mutex);
1784		btrfs_release_delayed_node(delayed_node);
1785		return -ENOENT;
1786	}
1787
1788	inode_item = &delayed_node->inode_item;
1789
1790	i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1791	i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1792	btrfs_i_size_write(inode, btrfs_stack_inode_size(inode_item));
1793	inode->i_mode = btrfs_stack_inode_mode(inode_item);
1794	set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1795	inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1796	BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1797	inode->i_version = btrfs_stack_inode_sequence(inode_item);
1798	inode->i_rdev = 0;
1799	*rdev = btrfs_stack_inode_rdev(inode_item);
1800	BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
1801
1802	tspec = btrfs_inode_atime(inode_item);
1803	inode->i_atime.tv_sec = btrfs_stack_timespec_sec(tspec);
1804	inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1805
1806	tspec = btrfs_inode_mtime(inode_item);
1807	inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(tspec);
1808	inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1809
1810	tspec = btrfs_inode_ctime(inode_item);
1811	inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(tspec);
1812	inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(tspec);
1813
1814	inode->i_generation = BTRFS_I(inode)->generation;
1815	BTRFS_I(inode)->index_cnt = (u64)-1;
1816
1817	mutex_unlock(&delayed_node->mutex);
1818	btrfs_release_delayed_node(delayed_node);
1819	return 0;
1820}
1821
1822int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1823			       struct btrfs_root *root, struct inode *inode)
1824{
1825	struct btrfs_delayed_node *delayed_node;
1826	int ret = 0;
1827
1828	delayed_node = btrfs_get_or_create_delayed_node(inode);
1829	if (IS_ERR(delayed_node))
1830		return PTR_ERR(delayed_node);
1831
1832	mutex_lock(&delayed_node->mutex);
1833	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1834		fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1835		goto release_node;
1836	}
1837
1838	ret = btrfs_delayed_inode_reserve_metadata(trans, root, inode,
1839						   delayed_node);
1840	if (ret)
1841		goto release_node;
 
 
1842
1843	fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1844	set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1845	delayed_node->count++;
1846	atomic_inc(&root->fs_info->delayed_root->items);
1847release_node:
1848	mutex_unlock(&delayed_node->mutex);
1849	btrfs_release_delayed_node(delayed_node);
1850	return ret;
1851}
1852
1853int btrfs_delayed_delete_inode_ref(struct inode *inode)
1854{
1855	struct btrfs_delayed_node *delayed_node;
1856
1857	delayed_node = btrfs_get_or_create_delayed_node(inode);
1858	if (IS_ERR(delayed_node))
1859		return PTR_ERR(delayed_node);
1860
1861	/*
1862	 * We don't reserve space for inode ref deletion is because:
1863	 * - We ONLY do async inode ref deletion for the inode who has only
1864	 *   one link(i_nlink == 1), it means there is only one inode ref.
1865	 *   And in most case, the inode ref and the inode item are in the
1866	 *   same leaf, and we will deal with them at the same time.
1867	 *   Since we are sure we will reserve the space for the inode item,
1868	 *   it is unnecessary to reserve space for inode ref deletion.
1869	 * - If the inode ref and the inode item are not in the same leaf,
1870	 *   We also needn't worry about enospc problem, because we reserve
1871	 *   much more space for the inode update than it needs.
1872	 * - At the worst, we can steal some space from the global reservation.
1873	 *   It is very rare.
1874	 */
1875	mutex_lock(&delayed_node->mutex);
1876	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1877		goto release_node;
1878
1879	set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1880	delayed_node->count++;
1881	atomic_inc(&BTRFS_I(inode)->root->fs_info->delayed_root->items);
1882release_node:
1883	mutex_unlock(&delayed_node->mutex);
1884	btrfs_release_delayed_node(delayed_node);
1885	return 0;
1886}
1887
1888static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1889{
1890	struct btrfs_root *root = delayed_node->root;
1891	struct btrfs_delayed_item *curr_item, *prev_item;
1892
1893	mutex_lock(&delayed_node->mutex);
1894	curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1895	while (curr_item) {
1896		btrfs_delayed_item_release_metadata(root, curr_item);
1897		prev_item = curr_item;
1898		curr_item = __btrfs_next_delayed_item(prev_item);
1899		btrfs_release_delayed_item(prev_item);
1900	}
1901
1902	curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1903	while (curr_item) {
1904		btrfs_delayed_item_release_metadata(root, curr_item);
1905		prev_item = curr_item;
1906		curr_item = __btrfs_next_delayed_item(prev_item);
1907		btrfs_release_delayed_item(prev_item);
1908	}
1909
1910	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1911		btrfs_release_delayed_iref(delayed_node);
1912
1913	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1914		btrfs_delayed_inode_release_metadata(root, delayed_node);
1915		btrfs_release_delayed_inode(delayed_node);
1916	}
1917	mutex_unlock(&delayed_node->mutex);
1918}
1919
1920void btrfs_kill_delayed_inode_items(struct inode *inode)
1921{
1922	struct btrfs_delayed_node *delayed_node;
1923
1924	delayed_node = btrfs_get_delayed_node(inode);
1925	if (!delayed_node)
1926		return;
1927
1928	__btrfs_kill_delayed_node(delayed_node);
1929	btrfs_release_delayed_node(delayed_node);
1930}
1931
1932void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1933{
1934	u64 inode_id = 0;
1935	struct btrfs_delayed_node *delayed_nodes[8];
1936	int i, n;
1937
1938	while (1) {
1939		spin_lock(&root->inode_lock);
1940		n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1941					   (void **)delayed_nodes, inode_id,
1942					   ARRAY_SIZE(delayed_nodes));
1943		if (!n) {
1944			spin_unlock(&root->inode_lock);
1945			break;
1946		}
1947
1948		inode_id = delayed_nodes[n - 1]->inode_id + 1;
1949
1950		for (i = 0; i < n; i++)
1951			atomic_inc(&delayed_nodes[i]->refs);
1952		spin_unlock(&root->inode_lock);
1953
1954		for (i = 0; i < n; i++) {
1955			__btrfs_kill_delayed_node(delayed_nodes[i]);
1956			btrfs_release_delayed_node(delayed_nodes[i]);
1957		}
1958	}
1959}
1960
1961void btrfs_destroy_delayed_inodes(struct btrfs_root *root)
1962{
1963	struct btrfs_delayed_root *delayed_root;
1964	struct btrfs_delayed_node *curr_node, *prev_node;
1965
1966	delayed_root = btrfs_get_delayed_root(root);
1967
1968	curr_node = btrfs_first_delayed_node(delayed_root);
1969	while (curr_node) {
1970		__btrfs_kill_delayed_node(curr_node);
1971
1972		prev_node = curr_node;
1973		curr_node = btrfs_next_delayed_node(curr_node);
1974		btrfs_release_delayed_node(prev_node);
1975	}
1976}
1977