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v4.10.11
 
   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_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	kmem_cache_destroy(delayed_node_cache);
  47}
  48
 
 
 
 
 
 
 
 
 
 
 
  49static inline void btrfs_init_delayed_node(
  50				struct btrfs_delayed_node *delayed_node,
  51				struct btrfs_root *root, u64 inode_id)
  52{
  53	delayed_node->root = root;
  54	delayed_node->inode_id = inode_id;
  55	atomic_set(&delayed_node->refs, 0);
  56	delayed_node->ins_root = RB_ROOT;
  57	delayed_node->del_root = RB_ROOT;
  58	mutex_init(&delayed_node->mutex);
  59	INIT_LIST_HEAD(&delayed_node->n_list);
  60	INIT_LIST_HEAD(&delayed_node->p_list);
  61}
  62
  63static inline int btrfs_is_continuous_delayed_item(
  64					struct btrfs_delayed_item *item1,
  65					struct btrfs_delayed_item *item2)
  66{
  67	if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
  68	    item1->key.objectid == item2->key.objectid &&
  69	    item1->key.type == item2->key.type &&
  70	    item1->key.offset + 1 == item2->key.offset)
  71		return 1;
  72	return 0;
  73}
  74
  75static struct btrfs_delayed_node *btrfs_get_delayed_node(struct inode *inode)
  76{
  77	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
  78	struct btrfs_root *root = btrfs_inode->root;
  79	u64 ino = btrfs_ino(inode);
  80	struct btrfs_delayed_node *node;
  81
  82	node = ACCESS_ONCE(btrfs_inode->delayed_node);
  83	if (node) {
  84		atomic_inc(&node->refs);
  85		return node;
  86	}
  87
  88	spin_lock(&root->inode_lock);
  89	node = radix_tree_lookup(&root->delayed_nodes_tree, ino);
 
  90	if (node) {
  91		if (btrfs_inode->delayed_node) {
  92			atomic_inc(&node->refs);	/* can be accessed */
  93			BUG_ON(btrfs_inode->delayed_node != node);
  94			spin_unlock(&root->inode_lock);
  95			return node;
  96		}
  97		btrfs_inode->delayed_node = node;
  98		/* can be accessed and cached in the inode */
  99		atomic_add(2, &node->refs);
 100		spin_unlock(&root->inode_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 101		return node;
 102	}
 103	spin_unlock(&root->inode_lock);
 104
 105	return NULL;
 106}
 107
 108/* Will return either the node or PTR_ERR(-ENOMEM) */
 109static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 110							struct inode *inode)
 111{
 112	struct btrfs_delayed_node *node;
 113	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
 114	struct btrfs_root *root = btrfs_inode->root;
 115	u64 ino = btrfs_ino(inode);
 116	int ret;
 
 117
 118again:
 119	node = btrfs_get_delayed_node(inode);
 120	if (node)
 121		return node;
 122
 123	node = kmem_cache_zalloc(delayed_node_cache, GFP_NOFS);
 124	if (!node)
 125		return ERR_PTR(-ENOMEM);
 126	btrfs_init_delayed_node(node, root, ino);
 127
 128	/* cached in the btrfs inode and can be accessed */
 129	atomic_add(2, &node->refs);
 130
 131	ret = radix_tree_preload(GFP_NOFS);
 132	if (ret) {
 
 133		kmem_cache_free(delayed_node_cache, node);
 134		return ERR_PTR(ret);
 135	}
 136
 137	spin_lock(&root->inode_lock);
 138	ret = radix_tree_insert(&root->delayed_nodes_tree, ino, node);
 139	if (ret == -EEXIST) {
 140		spin_unlock(&root->inode_lock);
 141		kmem_cache_free(delayed_node_cache, node);
 142		radix_tree_preload_end();
 143		goto again;
 144	}
 
 
 
 
 145	btrfs_inode->delayed_node = node;
 146	spin_unlock(&root->inode_lock);
 147	radix_tree_preload_end();
 148
 149	return node;
 150}
 151
 152/*
 153 * Call it when holding delayed_node->mutex
 154 *
 155 * If mod = 1, add this node into the prepared list.
 156 */
 157static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
 158				     struct btrfs_delayed_node *node,
 159				     int mod)
 160{
 161	spin_lock(&root->lock);
 162	if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 163		if (!list_empty(&node->p_list))
 164			list_move_tail(&node->p_list, &root->prepare_list);
 165		else if (mod)
 166			list_add_tail(&node->p_list, &root->prepare_list);
 167	} else {
 168		list_add_tail(&node->n_list, &root->node_list);
 169		list_add_tail(&node->p_list, &root->prepare_list);
 170		atomic_inc(&node->refs);	/* inserted into list */
 171		root->nodes++;
 172		set_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 173	}
 174	spin_unlock(&root->lock);
 175}
 176
 177/* Call it when holding delayed_node->mutex */
 178static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
 179				       struct btrfs_delayed_node *node)
 180{
 181	spin_lock(&root->lock);
 182	if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 183		root->nodes--;
 184		atomic_dec(&node->refs);	/* not in the list */
 185		list_del_init(&node->n_list);
 186		if (!list_empty(&node->p_list))
 187			list_del_init(&node->p_list);
 188		clear_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 189	}
 190	spin_unlock(&root->lock);
 191}
 192
 193static struct btrfs_delayed_node *btrfs_first_delayed_node(
 194			struct btrfs_delayed_root *delayed_root)
 195{
 196	struct list_head *p;
 197	struct btrfs_delayed_node *node = NULL;
 198
 199	spin_lock(&delayed_root->lock);
 200	if (list_empty(&delayed_root->node_list))
 201		goto out;
 202
 203	p = delayed_root->node_list.next;
 204	node = list_entry(p, struct btrfs_delayed_node, n_list);
 205	atomic_inc(&node->refs);
 206out:
 207	spin_unlock(&delayed_root->lock);
 208
 209	return node;
 210}
 211
 212static struct btrfs_delayed_node *btrfs_next_delayed_node(
 213						struct btrfs_delayed_node *node)
 214{
 215	struct btrfs_delayed_root *delayed_root;
 216	struct list_head *p;
 217	struct btrfs_delayed_node *next = NULL;
 218
 219	delayed_root = node->root->fs_info->delayed_root;
 220	spin_lock(&delayed_root->lock);
 221	if (!test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 222		/* not in the list */
 223		if (list_empty(&delayed_root->node_list))
 224			goto out;
 225		p = delayed_root->node_list.next;
 226	} else if (list_is_last(&node->n_list, &delayed_root->node_list))
 227		goto out;
 228	else
 229		p = node->n_list.next;
 230
 231	next = list_entry(p, struct btrfs_delayed_node, n_list);
 232	atomic_inc(&next->refs);
 233out:
 234	spin_unlock(&delayed_root->lock);
 235
 236	return next;
 237}
 238
 239static void __btrfs_release_delayed_node(
 240				struct btrfs_delayed_node *delayed_node,
 241				int mod)
 242{
 243	struct btrfs_delayed_root *delayed_root;
 244
 245	if (!delayed_node)
 246		return;
 247
 248	delayed_root = delayed_node->root->fs_info->delayed_root;
 249
 250	mutex_lock(&delayed_node->mutex);
 251	if (delayed_node->count)
 252		btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
 253	else
 254		btrfs_dequeue_delayed_node(delayed_root, delayed_node);
 255	mutex_unlock(&delayed_node->mutex);
 256
 257	if (atomic_dec_and_test(&delayed_node->refs)) {
 258		bool free = false;
 259		struct btrfs_root *root = delayed_node->root;
 260		spin_lock(&root->inode_lock);
 261		if (atomic_read(&delayed_node->refs) == 0) {
 262			radix_tree_delete(&root->delayed_nodes_tree,
 263					  delayed_node->inode_id);
 264			free = true;
 265		}
 266		spin_unlock(&root->inode_lock);
 267		if (free)
 268			kmem_cache_free(delayed_node_cache, delayed_node);
 269	}
 270}
 271
 272static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 273{
 274	__btrfs_release_delayed_node(node, 0);
 275}
 276
 277static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 278					struct btrfs_delayed_root *delayed_root)
 279{
 280	struct list_head *p;
 281	struct btrfs_delayed_node *node = NULL;
 282
 283	spin_lock(&delayed_root->lock);
 284	if (list_empty(&delayed_root->prepare_list))
 285		goto out;
 286
 287	p = delayed_root->prepare_list.next;
 288	list_del_init(p);
 289	node = list_entry(p, struct btrfs_delayed_node, p_list);
 290	atomic_inc(&node->refs);
 291out:
 292	spin_unlock(&delayed_root->lock);
 293
 294	return node;
 295}
 296
 297static inline void btrfs_release_prepared_delayed_node(
 298					struct btrfs_delayed_node *node)
 299{
 300	__btrfs_release_delayed_node(node, 1);
 301}
 302
 303static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
 
 
 304{
 305	struct btrfs_delayed_item *item;
 306	item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
 
 307	if (item) {
 308		item->data_len = data_len;
 309		item->ins_or_del = 0;
 310		item->bytes_reserved = 0;
 311		item->delayed_node = NULL;
 312		atomic_set(&item->refs, 1);
 
 
 
 313	}
 314	return item;
 315}
 316
 317/*
 318 * __btrfs_lookup_delayed_item - look up the delayed item by key
 
 319 * @delayed_node: pointer to the delayed node
 320 * @key:	  the key to look up
 321 * @prev:	  used to store the prev item if the right item isn't found
 322 * @next:	  used to store the next item if the right item isn't found
 323 *
 324 * Note: if we don't find the right item, we will return the prev item and
 325 * the next item.
 326 */
 327static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 328				struct rb_root *root,
 329				struct btrfs_key *key,
 330				struct btrfs_delayed_item **prev,
 331				struct btrfs_delayed_item **next)
 332{
 333	struct rb_node *node, *prev_node = NULL;
 334	struct btrfs_delayed_item *delayed_item = NULL;
 335	int ret = 0;
 336
 337	node = root->rb_node;
 338
 339	while (node) {
 340		delayed_item = rb_entry(node, struct btrfs_delayed_item,
 341					rb_node);
 342		prev_node = node;
 343		ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
 344		if (ret < 0)
 345			node = node->rb_right;
 346		else if (ret > 0)
 347			node = node->rb_left;
 348		else
 349			return delayed_item;
 350	}
 351
 352	if (prev) {
 353		if (!prev_node)
 354			*prev = NULL;
 355		else if (ret < 0)
 356			*prev = delayed_item;
 357		else if ((node = rb_prev(prev_node)) != NULL) {
 358			*prev = rb_entry(node, struct btrfs_delayed_item,
 359					 rb_node);
 360		} else
 361			*prev = NULL;
 362	}
 363
 364	if (next) {
 365		if (!prev_node)
 366			*next = NULL;
 367		else if (ret > 0)
 368			*next = delayed_item;
 369		else if ((node = rb_next(prev_node)) != NULL) {
 370			*next = rb_entry(node, struct btrfs_delayed_item,
 371					 rb_node);
 372		} else
 373			*next = NULL;
 374	}
 375	return NULL;
 376}
 377
 378static struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
 379					struct btrfs_delayed_node *delayed_node,
 380					struct btrfs_key *key)
 381{
 382	return __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
 383					   NULL, NULL);
 384}
 385
 386static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 387				    struct btrfs_delayed_item *ins,
 388				    int action)
 389{
 390	struct rb_node **p, *node;
 391	struct rb_node *parent_node = NULL;
 392	struct rb_root *root;
 393	struct btrfs_delayed_item *item;
 394	int cmp;
 395
 396	if (action == BTRFS_DELAYED_INSERTION_ITEM)
 397		root = &delayed_node->ins_root;
 398	else if (action == BTRFS_DELAYED_DELETION_ITEM)
 399		root = &delayed_node->del_root;
 400	else
 401		BUG();
 402	p = &root->rb_node;
 
 403	node = &ins->rb_node;
 404
 405	while (*p) {
 406		parent_node = *p;
 407		item = rb_entry(parent_node, struct btrfs_delayed_item,
 408				 rb_node);
 409
 410		cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
 411		if (cmp < 0)
 412			p = &(*p)->rb_right;
 413		else if (cmp > 0)
 
 414			p = &(*p)->rb_left;
 415		else
 416			return -EEXIST;
 
 417	}
 418
 419	rb_link_node(node, parent_node, p);
 420	rb_insert_color(node, root);
 421	ins->delayed_node = delayed_node;
 422	ins->ins_or_del = action;
 423
 424	if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
 425	    action == BTRFS_DELAYED_INSERTION_ITEM &&
 426	    ins->key.offset >= delayed_node->index_cnt)
 427			delayed_node->index_cnt = ins->key.offset + 1;
 428
 429	delayed_node->count++;
 430	atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 431	return 0;
 432}
 433
 434static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
 435					      struct btrfs_delayed_item *item)
 436{
 437	return __btrfs_add_delayed_item(node, item,
 438					BTRFS_DELAYED_INSERTION_ITEM);
 439}
 440
 441static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
 442					     struct btrfs_delayed_item *item)
 443{
 444	return __btrfs_add_delayed_item(node, item,
 445					BTRFS_DELAYED_DELETION_ITEM);
 446}
 447
 448static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 449{
 450	int seq = atomic_inc_return(&delayed_root->items_seq);
 451
 452	/*
 453	 * atomic_dec_return implies a barrier for waitqueue_active
 454	 */
 455	if ((atomic_dec_return(&delayed_root->items) <
 456	    BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) &&
 457	    waitqueue_active(&delayed_root->wait))
 458		wake_up(&delayed_root->wait);
 459}
 460
 461static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 462{
 463	struct rb_root *root;
 
 464	struct btrfs_delayed_root *delayed_root;
 465
 466	delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
 
 
 
 
 
 467
 468	BUG_ON(!delayed_root);
 469	BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
 470	       delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
 471
 472	if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
 473		root = &delayed_item->delayed_node->ins_root;
 474	else
 475		root = &delayed_item->delayed_node->del_root;
 476
 477	rb_erase(&delayed_item->rb_node, root);
 478	delayed_item->delayed_node->count--;
 
 479
 480	finish_one_item(delayed_root);
 481}
 482
 483static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 484{
 485	if (item) {
 486		__btrfs_remove_delayed_item(item);
 487		if (atomic_dec_and_test(&item->refs))
 488			kfree(item);
 489	}
 490}
 491
 492static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
 493					struct btrfs_delayed_node *delayed_node)
 494{
 495	struct rb_node *p;
 496	struct btrfs_delayed_item *item = NULL;
 497
 498	p = rb_first(&delayed_node->ins_root);
 499	if (p)
 500		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 501
 502	return item;
 503}
 504
 505static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 506					struct btrfs_delayed_node *delayed_node)
 507{
 508	struct rb_node *p;
 509	struct btrfs_delayed_item *item = NULL;
 510
 511	p = rb_first(&delayed_node->del_root);
 512	if (p)
 513		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 514
 515	return item;
 516}
 517
 518static struct btrfs_delayed_item *__btrfs_next_delayed_item(
 519						struct btrfs_delayed_item *item)
 520{
 521	struct rb_node *p;
 522	struct btrfs_delayed_item *next = NULL;
 523
 524	p = rb_next(&item->rb_node);
 525	if (p)
 526		next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 527
 528	return next;
 529}
 530
 531static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 532					       struct btrfs_fs_info *fs_info,
 533					       struct btrfs_delayed_item *item)
 534{
 535	struct btrfs_block_rsv *src_rsv;
 536	struct btrfs_block_rsv *dst_rsv;
 
 537	u64 num_bytes;
 538	int ret;
 539
 540	if (!trans->bytes_reserved)
 541		return 0;
 542
 543	src_rsv = trans->block_rsv;
 544	dst_rsv = &fs_info->delayed_block_rsv;
 545
 546	num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 547	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 
 
 
 
 
 
 548	if (!ret) {
 549		trace_btrfs_space_reservation(fs_info, "delayed_item",
 550					      item->key.objectid,
 551					      num_bytes, 1);
 552		item->bytes_reserved = num_bytes;
 
 
 
 
 
 
 553	}
 554
 555	return ret;
 556}
 557
 558static void btrfs_delayed_item_release_metadata(struct btrfs_fs_info *fs_info,
 559						struct btrfs_delayed_item *item)
 560{
 561	struct btrfs_block_rsv *rsv;
 
 562
 563	if (!item->bytes_reserved)
 564		return;
 565
 566	rsv = &fs_info->delayed_block_rsv;
 
 
 
 
 567	trace_btrfs_space_reservation(fs_info, "delayed_item",
 568				      item->key.objectid, item->bytes_reserved,
 569				      0);
 570	btrfs_block_rsv_release(fs_info, rsv,
 571				item->bytes_reserved);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 572}
 573
 574static int btrfs_delayed_inode_reserve_metadata(
 575					struct btrfs_trans_handle *trans,
 576					struct btrfs_root *root,
 577					struct inode *inode,
 578					struct btrfs_delayed_node *node)
 579{
 580	struct btrfs_fs_info *fs_info = root->fs_info;
 581	struct btrfs_block_rsv *src_rsv;
 582	struct btrfs_block_rsv *dst_rsv;
 583	u64 num_bytes;
 584	int ret;
 585	bool release = false;
 586
 587	src_rsv = trans->block_rsv;
 588	dst_rsv = &fs_info->delayed_block_rsv;
 589
 590	num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 591
 592	/*
 593	 * If our block_rsv is the delalloc block reserve then check and see if
 594	 * we have our extra reservation for updating the inode.  If not fall
 595	 * through and try to reserve space quickly.
 596	 *
 597	 * We used to try and steal from the delalloc block rsv or the global
 598	 * reserve, but we'd steal a full reservation, which isn't kind.  We are
 599	 * here through delalloc which means we've likely just cowed down close
 600	 * to the leaf that contains the inode, so we would steal less just
 601	 * doing the fallback inode update, so if we do end up having to steal
 602	 * from the global block rsv we hopefully only steal one or two blocks
 603	 * worth which is less likely to hurt us.
 604	 */
 605	if (src_rsv && src_rsv->type == BTRFS_BLOCK_RSV_DELALLOC) {
 606		spin_lock(&BTRFS_I(inode)->lock);
 607		if (test_and_clear_bit(BTRFS_INODE_DELALLOC_META_RESERVED,
 608				       &BTRFS_I(inode)->runtime_flags))
 609			release = true;
 610		else
 611			src_rsv = NULL;
 612		spin_unlock(&BTRFS_I(inode)->lock);
 613	}
 614
 615	/*
 616	 * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 617	 * which doesn't reserve space for speed.  This is a problem since we
 618	 * still need to reserve space for this update, so try to reserve the
 619	 * space.
 620	 *
 621	 * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
 622	 * we're accounted for.
 623	 */
 624	if (!src_rsv || (!trans->bytes_reserved &&
 625			 src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
 626		ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 
 
 
 
 627					  BTRFS_RESERVE_NO_FLUSH);
 628		/*
 629		 * Since we're under a transaction reserve_metadata_bytes could
 630		 * try to commit the transaction which will make it return
 631		 * EAGAIN to make us stop the transaction we have, so return
 632		 * ENOSPC instead so that btrfs_dirty_inode knows what to do.
 633		 */
 634		if (ret == -EAGAIN)
 635			ret = -ENOSPC;
 636		if (!ret) {
 637			node->bytes_reserved = num_bytes;
 638			trace_btrfs_space_reservation(fs_info,
 639						      "delayed_inode",
 640						      btrfs_ino(inode),
 641						      num_bytes, 1);
 642		}
 643		return ret;
 644	}
 645
 646	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 647
 648	/*
 649	 * Migrate only takes a reservation, it doesn't touch the size of the
 650	 * block_rsv.  This is to simplify people who don't normally have things
 651	 * migrated from their block rsv.  If they go to release their
 652	 * reservation, that will decrease the size as well, so if migrate
 653	 * reduced size we'd end up with a negative size.  But for the
 654	 * delalloc_meta_reserved stuff we will only know to drop 1 reservation,
 655	 * but we could in fact do this reserve/migrate dance several times
 656	 * between the time we did the original reservation and we'd clean it
 657	 * up.  So to take care of this, release the space for the meta
 658	 * reservation here.  I think it may be time for a documentation page on
 659	 * how block rsvs. work.
 660	 */
 661	if (!ret) {
 662		trace_btrfs_space_reservation(fs_info, "delayed_inode",
 663					      btrfs_ino(inode), num_bytes, 1);
 664		node->bytes_reserved = num_bytes;
 665	}
 666
 667	if (release) {
 668		trace_btrfs_space_reservation(fs_info, "delalloc",
 669					      btrfs_ino(inode), num_bytes, 0);
 670		btrfs_block_rsv_release(fs_info, src_rsv, num_bytes);
 671	}
 672
 673	return ret;
 674}
 675
 676static void btrfs_delayed_inode_release_metadata(struct btrfs_fs_info *fs_info,
 677						struct btrfs_delayed_node *node)
 
 678{
 679	struct btrfs_block_rsv *rsv;
 680
 681	if (!node->bytes_reserved)
 682		return;
 683
 684	rsv = &fs_info->delayed_block_rsv;
 685	trace_btrfs_space_reservation(fs_info, "delayed_inode",
 686				      node->inode_id, node->bytes_reserved, 0);
 687	btrfs_block_rsv_release(fs_info, rsv,
 
 
 
 
 
 688				node->bytes_reserved);
 689	node->bytes_reserved = 0;
 690}
 691
 692/*
 693 * This helper will insert some continuous items into the same leaf according
 694 * to the free space of the leaf.
 
 
 
 
 
 
 695 */
 696static int btrfs_batch_insert_items(struct btrfs_root *root,
 697				    struct btrfs_path *path,
 698				    struct btrfs_delayed_item *item)
 
 699{
 700	struct btrfs_fs_info *fs_info = root->fs_info;
 701	struct btrfs_delayed_item *curr, *next;
 702	int free_space;
 703	int total_data_size = 0, total_size = 0;
 704	struct extent_buffer *leaf;
 705	char *data_ptr;
 706	struct btrfs_key *keys;
 707	u32 *data_size;
 708	struct list_head head;
 709	int slot;
 710	int nitems;
 711	int i;
 712	int ret = 0;
 713
 714	BUG_ON(!path->nodes[0]);
 715
 716	leaf = path->nodes[0];
 717	free_space = btrfs_leaf_free_space(fs_info, leaf);
 718	INIT_LIST_HEAD(&head);
 719
 720	next = item;
 721	nitems = 0;
 
 
 
 
 
 
 
 
 
 722
 723	/*
 724	 * count the number of the continuous items that we can insert in batch
 
 
 
 725	 */
 726	while (total_size + next->data_len + sizeof(struct btrfs_item) <=
 727	       free_space) {
 728		total_data_size += next->data_len;
 729		total_size += next->data_len + sizeof(struct btrfs_item);
 730		list_add_tail(&next->tree_list, &head);
 731		nitems++;
 
 
 
 
 732
 733		curr = next;
 734		next = __btrfs_next_delayed_item(curr);
 735		if (!next)
 736			break;
 737
 738		if (!btrfs_is_continuous_delayed_item(curr, next))
 
 
 
 
 739			break;
 740	}
 741
 742	if (!nitems) {
 743		ret = 0;
 744		goto out;
 745	}
 746
 747	/*
 748	 * we need allocate some memory space, but it might cause the task
 749	 * to sleep, so we set all locked nodes in the path to blocking locks
 750	 * first.
 751	 */
 752	btrfs_set_path_blocking(path);
 753
 754	keys = kmalloc_array(nitems, sizeof(struct btrfs_key), GFP_NOFS);
 755	if (!keys) {
 756		ret = -ENOMEM;
 757		goto out;
 
 758	}
 759
 760	data_size = kmalloc_array(nitems, sizeof(u32), GFP_NOFS);
 761	if (!data_size) {
 762		ret = -ENOMEM;
 763		goto error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 764	}
 765
 766	/* get keys of all the delayed items */
 767	i = 0;
 768	list_for_each_entry(next, &head, tree_list) {
 769		keys[i] = next->key;
 770		data_size[i] = next->data_len;
 771		i++;
 772	}
 773
 774	/* reset all the locked nodes in the patch to spinning locks. */
 775	btrfs_clear_path_blocking(path, NULL, 0);
 
 
 
 776
 777	/* insert the keys of the items */
 778	setup_items_for_insert(root, path, keys, data_size,
 779			       total_data_size, total_size, nitems);
 
 
 
 780
 781	/* insert the dir index items */
 782	slot = path->slots[0];
 783	list_for_each_entry_safe(curr, next, &head, tree_list) {
 784		data_ptr = btrfs_item_ptr(leaf, slot, char);
 785		write_extent_buffer(leaf, &curr->data,
 786				    (unsigned long)data_ptr,
 787				    curr->data_len);
 788		slot++;
 789
 790		btrfs_delayed_item_release_metadata(fs_info, curr);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 791
 
 792		list_del(&curr->tree_list);
 793		btrfs_release_delayed_item(curr);
 794	}
 795
 796error:
 797	kfree(data_size);
 798	kfree(keys);
 799out:
 
 800	return ret;
 801}
 802
 803/*
 804 * This helper can just do simple insertion that needn't extend item for new
 805 * data, such as directory name index insertion, inode insertion.
 806 */
 807static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 808				     struct btrfs_root *root,
 809				     struct btrfs_path *path,
 810				     struct btrfs_delayed_item *delayed_item)
 811{
 812	struct btrfs_fs_info *fs_info = root->fs_info;
 813	struct extent_buffer *leaf;
 814	char *ptr;
 815	int ret;
 816
 817	ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
 818				      delayed_item->data_len);
 819	if (ret < 0 && ret != -EEXIST)
 820		return ret;
 821
 822	leaf = path->nodes[0];
 823
 824	ptr = btrfs_item_ptr(leaf, path->slots[0], char);
 825
 826	write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
 827			    delayed_item->data_len);
 828	btrfs_mark_buffer_dirty(leaf);
 829
 830	btrfs_delayed_item_release_metadata(fs_info, delayed_item);
 831	return 0;
 832}
 833
 834/*
 835 * we insert an item first, then if there are some continuous items, we try
 836 * to insert those items into the same leaf.
 837 */
 838static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 839				      struct btrfs_path *path,
 840				      struct btrfs_root *root,
 841				      struct btrfs_delayed_node *node)
 842{
 843	struct btrfs_delayed_item *curr, *prev;
 844	int ret = 0;
 845
 846do_again:
 847	mutex_lock(&node->mutex);
 848	curr = __btrfs_first_delayed_insertion_item(node);
 849	if (!curr)
 850		goto insert_end;
 851
 852	ret = btrfs_insert_delayed_item(trans, root, path, curr);
 853	if (ret < 0) {
 854		btrfs_release_path(path);
 855		goto insert_end;
 856	}
 857
 858	prev = curr;
 859	curr = __btrfs_next_delayed_item(prev);
 860	if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
 861		/* insert the continuous items into the same leaf */
 862		path->slots[0]++;
 863		btrfs_batch_insert_items(root, path, curr);
 
 
 864	}
 865	btrfs_release_delayed_item(prev);
 866	btrfs_mark_buffer_dirty(path->nodes[0]);
 867
 868	btrfs_release_path(path);
 869	mutex_unlock(&node->mutex);
 870	goto do_again;
 871
 872insert_end:
 873	mutex_unlock(&node->mutex);
 874	return ret;
 875}
 876
 877static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
 878				    struct btrfs_root *root,
 879				    struct btrfs_path *path,
 880				    struct btrfs_delayed_item *item)
 881{
 
 882	struct btrfs_fs_info *fs_info = root->fs_info;
 883	struct btrfs_delayed_item *curr, *next;
 884	struct extent_buffer *leaf;
 885	struct btrfs_key key;
 886	struct list_head head;
 887	int nitems, i, last_item;
 888	int ret = 0;
 889
 890	BUG_ON(!path->nodes[0]);
 891
 892	leaf = path->nodes[0];
 
 
 
 
 
 
 
 
 
 
 
 
 893
 894	i = path->slots[0];
 895	last_item = btrfs_header_nritems(leaf) - 1;
 896	if (i > last_item)
 897		return -ENOENT;	/* FIXME: Is errno suitable? */
 898
 899	next = item;
 900	INIT_LIST_HEAD(&head);
 901	btrfs_item_key_to_cpu(leaf, &key, i);
 902	nitems = 0;
 903	/*
 904	 * count the number of the dir index items that we can delete in batch
 
 
 905	 */
 906	while (btrfs_comp_cpu_keys(&next->key, &key) == 0) {
 907		list_add_tail(&next->tree_list, &head);
 908		nitems++;
 909
 910		curr = next;
 911		next = __btrfs_next_delayed_item(curr);
 912		if (!next)
 913			break;
 914
 915		if (!btrfs_is_continuous_delayed_item(curr, next))
 916			break;
 917
 918		i++;
 919		if (i > last_item)
 920			break;
 921		btrfs_item_key_to_cpu(leaf, &key, i);
 
 
 
 922	}
 923
 924	if (!nitems)
 925		return 0;
 926
 927	ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 928	if (ret)
 929		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 930
 931	list_for_each_entry_safe(curr, next, &head, tree_list) {
 932		btrfs_delayed_item_release_metadata(fs_info, curr);
 933		list_del(&curr->tree_list);
 934		btrfs_release_delayed_item(curr);
 935	}
 936
 937out:
 938	return ret;
 939}
 940
 941static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 942				      struct btrfs_path *path,
 943				      struct btrfs_root *root,
 944				      struct btrfs_delayed_node *node)
 945{
 946	struct btrfs_delayed_item *curr, *prev;
 947	int ret = 0;
 948
 949do_again:
 950	mutex_lock(&node->mutex);
 951	curr = __btrfs_first_delayed_deletion_item(node);
 952	if (!curr)
 953		goto delete_fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 954
 955	ret = btrfs_search_slot(trans, root, &curr->key, path, -1, 1);
 956	if (ret < 0)
 957		goto delete_fail;
 958	else if (ret > 0) {
 959		/*
 960		 * can't find the item which the node points to, so this node
 961		 * is invalid, just drop it.
 
 
 
 962		 */
 963		prev = curr;
 964		curr = __btrfs_next_delayed_item(prev);
 965		btrfs_release_delayed_item(prev);
 966		ret = 0;
 967		btrfs_release_path(path);
 968		if (curr) {
 969			mutex_unlock(&node->mutex);
 970			goto do_again;
 971		} else
 972			goto delete_fail;
 973	}
 974
 975	btrfs_batch_delete_items(trans, root, path, curr);
 976	btrfs_release_path(path);
 977	mutex_unlock(&node->mutex);
 978	goto do_again;
 979
 980delete_fail:
 981	btrfs_release_path(path);
 982	mutex_unlock(&node->mutex);
 983	return ret;
 984}
 985
 986static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
 987{
 988	struct btrfs_delayed_root *delayed_root;
 989
 990	if (delayed_node &&
 991	    test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
 992		BUG_ON(!delayed_node->root);
 993		clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
 994		delayed_node->count--;
 995
 996		delayed_root = delayed_node->root->fs_info->delayed_root;
 997		finish_one_item(delayed_root);
 998	}
 999}
1000
1001static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
1002{
1003	struct btrfs_delayed_root *delayed_root;
1004
1005	ASSERT(delayed_node->root);
1006	clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1007	delayed_node->count--;
1008
1009	delayed_root = delayed_node->root->fs_info->delayed_root;
1010	finish_one_item(delayed_root);
 
 
 
 
1011}
1012
1013static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1014					struct btrfs_root *root,
1015					struct btrfs_path *path,
1016					struct btrfs_delayed_node *node)
1017{
1018	struct btrfs_fs_info *fs_info = root->fs_info;
1019	struct btrfs_key key;
1020	struct btrfs_inode_item *inode_item;
1021	struct extent_buffer *leaf;
1022	int mod;
1023	int ret;
1024
1025	key.objectid = node->inode_id;
1026	key.type = BTRFS_INODE_ITEM_KEY;
1027	key.offset = 0;
1028
1029	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1030		mod = -1;
1031	else
1032		mod = 1;
1033
1034	ret = btrfs_lookup_inode(trans, root, path, &key, mod);
1035	if (ret > 0) {
1036		btrfs_release_path(path);
1037		return -ENOENT;
1038	} else if (ret < 0) {
1039		return ret;
1040	}
1041
1042	leaf = path->nodes[0];
1043	inode_item = btrfs_item_ptr(leaf, path->slots[0],
1044				    struct btrfs_inode_item);
1045	write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1046			    sizeof(struct btrfs_inode_item));
1047	btrfs_mark_buffer_dirty(leaf);
1048
1049	if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1050		goto no_iref;
1051
1052	path->slots[0]++;
1053	if (path->slots[0] >= btrfs_header_nritems(leaf))
1054		goto search;
1055again:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1056	btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1057	if (key.objectid != node->inode_id)
1058		goto out;
1059
1060	if (key.type != BTRFS_INODE_REF_KEY &&
1061	    key.type != BTRFS_INODE_EXTREF_KEY)
1062		goto out;
1063
1064	/*
1065	 * Delayed iref deletion is for the inode who has only one link,
1066	 * so there is only one iref. The case that several irefs are
1067	 * in the same item doesn't exist.
1068	 */
1069	btrfs_del_item(trans, root, path);
1070out:
1071	btrfs_release_delayed_iref(node);
1072no_iref:
1073	btrfs_release_path(path);
1074err_out:
1075	btrfs_delayed_inode_release_metadata(fs_info, node);
1076	btrfs_release_delayed_inode(node);
1077
1078	return ret;
1079
1080search:
1081	btrfs_release_path(path);
1082
1083	key.type = BTRFS_INODE_EXTREF_KEY;
1084	key.offset = -1;
1085	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1086	if (ret < 0)
1087		goto err_out;
1088	ASSERT(ret);
1089
1090	ret = 0;
1091	leaf = path->nodes[0];
1092	path->slots[0]--;
1093	goto again;
1094}
1095
1096static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1097					     struct btrfs_root *root,
1098					     struct btrfs_path *path,
1099					     struct btrfs_delayed_node *node)
1100{
1101	int ret;
1102
1103	mutex_lock(&node->mutex);
1104	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
1105		mutex_unlock(&node->mutex);
1106		return 0;
1107	}
1108
1109	ret = __btrfs_update_delayed_inode(trans, root, path, node);
1110	mutex_unlock(&node->mutex);
1111	return ret;
1112}
1113
1114static inline int
1115__btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1116				   struct btrfs_path *path,
1117				   struct btrfs_delayed_node *node)
1118{
1119	int ret;
1120
1121	ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1122	if (ret)
1123		return ret;
1124
1125	ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1126	if (ret)
1127		return ret;
1128
 
 
 
1129	ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1130	return ret;
1131}
1132
1133/*
1134 * Called when committing the transaction.
1135 * Returns 0 on success.
1136 * Returns < 0 on error and returns with an aborted transaction with any
1137 * outstanding delayed items cleaned up.
1138 */
1139static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1140				     struct btrfs_fs_info *fs_info, int nr)
1141{
 
1142	struct btrfs_delayed_root *delayed_root;
1143	struct btrfs_delayed_node *curr_node, *prev_node;
1144	struct btrfs_path *path;
1145	struct btrfs_block_rsv *block_rsv;
1146	int ret = 0;
1147	bool count = (nr > 0);
1148
1149	if (trans->aborted)
1150		return -EIO;
1151
1152	path = btrfs_alloc_path();
1153	if (!path)
1154		return -ENOMEM;
1155	path->leave_spinning = 1;
1156
1157	block_rsv = trans->block_rsv;
1158	trans->block_rsv = &fs_info->delayed_block_rsv;
1159
1160	delayed_root = fs_info->delayed_root;
1161
1162	curr_node = btrfs_first_delayed_node(delayed_root);
1163	while (curr_node && (!count || (count && nr--))) {
1164		ret = __btrfs_commit_inode_delayed_items(trans, path,
1165							 curr_node);
1166		if (ret) {
1167			btrfs_release_delayed_node(curr_node);
1168			curr_node = NULL;
1169			btrfs_abort_transaction(trans, ret);
1170			break;
1171		}
1172
1173		prev_node = curr_node;
1174		curr_node = btrfs_next_delayed_node(curr_node);
 
 
 
 
 
 
 
1175		btrfs_release_delayed_node(prev_node);
1176	}
1177
 
 
 
 
 
 
 
 
 
1178	if (curr_node)
1179		btrfs_release_delayed_node(curr_node);
1180	btrfs_free_path(path);
1181	trans->block_rsv = block_rsv;
1182
1183	return ret;
1184}
1185
1186int btrfs_run_delayed_items(struct btrfs_trans_handle *trans,
1187			    struct btrfs_fs_info *fs_info)
1188{
1189	return __btrfs_run_delayed_items(trans, fs_info, -1);
1190}
1191
1192int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans,
1193			       struct btrfs_fs_info *fs_info, int nr)
1194{
1195	return __btrfs_run_delayed_items(trans, fs_info, nr);
1196}
1197
1198int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1199				     struct inode *inode)
1200{
1201	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1202	struct btrfs_path *path;
1203	struct btrfs_block_rsv *block_rsv;
1204	int ret;
1205
1206	if (!delayed_node)
1207		return 0;
1208
1209	mutex_lock(&delayed_node->mutex);
1210	if (!delayed_node->count) {
1211		mutex_unlock(&delayed_node->mutex);
1212		btrfs_release_delayed_node(delayed_node);
1213		return 0;
1214	}
1215	mutex_unlock(&delayed_node->mutex);
1216
1217	path = btrfs_alloc_path();
1218	if (!path) {
1219		btrfs_release_delayed_node(delayed_node);
1220		return -ENOMEM;
1221	}
1222	path->leave_spinning = 1;
1223
1224	block_rsv = trans->block_rsv;
1225	trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1226
1227	ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1228
1229	btrfs_release_delayed_node(delayed_node);
1230	btrfs_free_path(path);
1231	trans->block_rsv = block_rsv;
1232
1233	return ret;
1234}
1235
1236int btrfs_commit_inode_delayed_inode(struct inode *inode)
1237{
1238	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1239	struct btrfs_trans_handle *trans;
1240	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1241	struct btrfs_path *path;
1242	struct btrfs_block_rsv *block_rsv;
1243	int ret;
1244
1245	if (!delayed_node)
1246		return 0;
1247
1248	mutex_lock(&delayed_node->mutex);
1249	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1250		mutex_unlock(&delayed_node->mutex);
1251		btrfs_release_delayed_node(delayed_node);
1252		return 0;
1253	}
1254	mutex_unlock(&delayed_node->mutex);
1255
1256	trans = btrfs_join_transaction(delayed_node->root);
1257	if (IS_ERR(trans)) {
1258		ret = PTR_ERR(trans);
1259		goto out;
1260	}
1261
1262	path = btrfs_alloc_path();
1263	if (!path) {
1264		ret = -ENOMEM;
1265		goto trans_out;
1266	}
1267	path->leave_spinning = 1;
1268
1269	block_rsv = trans->block_rsv;
1270	trans->block_rsv = &fs_info->delayed_block_rsv;
1271
1272	mutex_lock(&delayed_node->mutex);
1273	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
1274		ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1275						   path, delayed_node);
1276	else
1277		ret = 0;
1278	mutex_unlock(&delayed_node->mutex);
1279
1280	btrfs_free_path(path);
1281	trans->block_rsv = block_rsv;
1282trans_out:
1283	btrfs_end_transaction(trans);
1284	btrfs_btree_balance_dirty(fs_info);
1285out:
1286	btrfs_release_delayed_node(delayed_node);
1287
1288	return ret;
1289}
1290
1291void btrfs_remove_delayed_node(struct inode *inode)
1292{
1293	struct btrfs_delayed_node *delayed_node;
1294
1295	delayed_node = ACCESS_ONCE(BTRFS_I(inode)->delayed_node);
1296	if (!delayed_node)
1297		return;
1298
1299	BTRFS_I(inode)->delayed_node = NULL;
1300	btrfs_release_delayed_node(delayed_node);
1301}
1302
1303struct btrfs_async_delayed_work {
1304	struct btrfs_delayed_root *delayed_root;
1305	int nr;
1306	struct btrfs_work work;
1307};
1308
1309static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1310{
1311	struct btrfs_async_delayed_work *async_work;
1312	struct btrfs_delayed_root *delayed_root;
1313	struct btrfs_trans_handle *trans;
1314	struct btrfs_path *path;
1315	struct btrfs_delayed_node *delayed_node = NULL;
1316	struct btrfs_root *root;
1317	struct btrfs_block_rsv *block_rsv;
1318	int total_done = 0;
1319
1320	async_work = container_of(work, struct btrfs_async_delayed_work, work);
1321	delayed_root = async_work->delayed_root;
1322
1323	path = btrfs_alloc_path();
1324	if (!path)
1325		goto out;
1326
1327again:
1328	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND / 2)
1329		goto free_path;
 
1330
1331	delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1332	if (!delayed_node)
1333		goto free_path;
1334
1335	path->leave_spinning = 1;
1336	root = delayed_node->root;
1337
1338	trans = btrfs_join_transaction(root);
1339	if (IS_ERR(trans))
1340		goto release_path;
 
 
 
 
1341
1342	block_rsv = trans->block_rsv;
1343	trans->block_rsv = &root->fs_info->delayed_block_rsv;
1344
1345	__btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1346
1347	trans->block_rsv = block_rsv;
1348	btrfs_end_transaction(trans);
1349	btrfs_btree_balance_dirty_nodelay(root->fs_info);
1350
1351release_path:
1352	btrfs_release_path(path);
1353	total_done++;
1354
1355	btrfs_release_prepared_delayed_node(delayed_node);
1356	if ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK) ||
1357	    total_done < async_work->nr)
1358		goto again;
1359
1360free_path:
1361	btrfs_free_path(path);
1362out:
1363	wake_up(&delayed_root->wait);
1364	kfree(async_work);
1365}
1366
1367
1368static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1369				     struct btrfs_fs_info *fs_info, int nr)
1370{
1371	struct btrfs_async_delayed_work *async_work;
1372
1373	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND ||
1374	    btrfs_workqueue_normal_congested(fs_info->delayed_workers))
1375		return 0;
1376
1377	async_work = kmalloc(sizeof(*async_work), GFP_NOFS);
1378	if (!async_work)
1379		return -ENOMEM;
1380
1381	async_work->delayed_root = delayed_root;
1382	btrfs_init_work(&async_work->work, btrfs_delayed_meta_helper,
1383			btrfs_async_run_delayed_root, NULL, NULL);
1384	async_work->nr = nr;
1385
1386	btrfs_queue_work(fs_info->delayed_workers, &async_work->work);
1387	return 0;
1388}
1389
1390void btrfs_assert_delayed_root_empty(struct btrfs_fs_info *fs_info)
1391{
1392	WARN_ON(btrfs_first_delayed_node(fs_info->delayed_root));
1393}
1394
1395static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
1396{
1397	int val = atomic_read(&delayed_root->items_seq);
1398
1399	if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
1400		return 1;
1401
1402	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1403		return 1;
1404
1405	return 0;
1406}
1407
1408void btrfs_balance_delayed_items(struct btrfs_fs_info *fs_info)
1409{
1410	struct btrfs_delayed_root *delayed_root = fs_info->delayed_root;
1411
1412	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
 
1413		return;
1414
1415	if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1416		int seq;
1417		int ret;
1418
1419		seq = atomic_read(&delayed_root->items_seq);
1420
1421		ret = btrfs_wq_run_delayed_node(delayed_root, fs_info, 0);
1422		if (ret)
1423			return;
1424
1425		wait_event_interruptible(delayed_root->wait,
1426					 could_end_wait(delayed_root, seq));
1427		return;
1428	}
1429
1430	btrfs_wq_run_delayed_node(delayed_root, fs_info, BTRFS_DELAYED_BATCH);
1431}
1432
1433/* Will return 0 or -ENOMEM */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1434int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
1435				   struct btrfs_fs_info *fs_info,
1436				   const char *name, int name_len,
1437				   struct inode *dir,
1438				   struct btrfs_disk_key *disk_key, u8 type,
1439				   u64 index)
1440{
 
 
1441	struct btrfs_delayed_node *delayed_node;
1442	struct btrfs_delayed_item *delayed_item;
1443	struct btrfs_dir_item *dir_item;
 
 
1444	int ret;
1445
1446	delayed_node = btrfs_get_or_create_delayed_node(dir);
1447	if (IS_ERR(delayed_node))
1448		return PTR_ERR(delayed_node);
1449
1450	delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len);
 
 
1451	if (!delayed_item) {
1452		ret = -ENOMEM;
1453		goto release_node;
1454	}
1455
1456	delayed_item->key.objectid = btrfs_ino(dir);
1457	delayed_item->key.type = BTRFS_DIR_INDEX_KEY;
1458	delayed_item->key.offset = index;
1459
1460	dir_item = (struct btrfs_dir_item *)delayed_item->data;
1461	dir_item->location = *disk_key;
1462	btrfs_set_stack_dir_transid(dir_item, trans->transid);
1463	btrfs_set_stack_dir_data_len(dir_item, 0);
1464	btrfs_set_stack_dir_name_len(dir_item, name_len);
1465	btrfs_set_stack_dir_type(dir_item, type);
1466	memcpy((char *)(dir_item + 1), name, name_len);
1467
1468	ret = btrfs_delayed_item_reserve_metadata(trans, fs_info, delayed_item);
 
 
 
1469	/*
1470	 * we have reserved enough space when we start a new transaction,
1471	 * so reserving metadata failure is impossible
 
 
 
 
1472	 */
1473	BUG_ON(ret);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1474
 
 
 
 
 
 
 
 
 
 
 
 
1475
1476	mutex_lock(&delayed_node->mutex);
1477	ret = __btrfs_add_delayed_insertion_item(delayed_node, delayed_item);
1478	if (unlikely(ret)) {
1479		btrfs_err(fs_info,
1480			  "err add delayed dir index item(name: %.*s) into the insertion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1481			  name_len, name, delayed_node->root->objectid,
1482			  delayed_node->inode_id, ret);
1483		BUG();
1484	}
1485	mutex_unlock(&delayed_node->mutex);
1486
1487release_node:
1488	btrfs_release_delayed_node(delayed_node);
1489	return ret;
1490}
1491
1492static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info,
1493					       struct btrfs_delayed_node *node,
1494					       struct btrfs_key *key)
1495{
1496	struct btrfs_delayed_item *item;
1497
1498	mutex_lock(&node->mutex);
1499	item = __btrfs_lookup_delayed_insertion_item(node, key);
1500	if (!item) {
1501		mutex_unlock(&node->mutex);
1502		return 1;
1503	}
1504
1505	btrfs_delayed_item_release_metadata(fs_info, item);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1506	btrfs_release_delayed_item(item);
 
 
 
 
 
 
 
1507	mutex_unlock(&node->mutex);
1508	return 0;
1509}
1510
1511int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1512				   struct btrfs_fs_info *fs_info,
1513				   struct inode *dir, u64 index)
1514{
1515	struct btrfs_delayed_node *node;
1516	struct btrfs_delayed_item *item;
1517	struct btrfs_key item_key;
1518	int ret;
1519
1520	node = btrfs_get_or_create_delayed_node(dir);
1521	if (IS_ERR(node))
1522		return PTR_ERR(node);
1523
1524	item_key.objectid = btrfs_ino(dir);
1525	item_key.type = BTRFS_DIR_INDEX_KEY;
1526	item_key.offset = index;
1527
1528	ret = btrfs_delete_delayed_insertion_item(fs_info, node, &item_key);
1529	if (!ret)
1530		goto end;
1531
1532	item = btrfs_alloc_delayed_item(0);
1533	if (!item) {
1534		ret = -ENOMEM;
1535		goto end;
1536	}
1537
1538	item->key = item_key;
1539
1540	ret = btrfs_delayed_item_reserve_metadata(trans, fs_info, item);
1541	/*
1542	 * we have reserved enough space when we start a new transaction,
1543	 * so reserving metadata failure is impossible.
1544	 */
1545	BUG_ON(ret);
 
 
 
 
 
1546
1547	mutex_lock(&node->mutex);
1548	ret = __btrfs_add_delayed_deletion_item(node, item);
1549	if (unlikely(ret)) {
1550		btrfs_err(fs_info,
1551			  "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1552			  index, node->root->objectid, node->inode_id, ret);
1553		BUG();
 
 
1554	}
1555	mutex_unlock(&node->mutex);
1556end:
1557	btrfs_release_delayed_node(node);
1558	return ret;
1559}
1560
1561int btrfs_inode_delayed_dir_index_count(struct inode *inode)
1562{
1563	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1564
1565	if (!delayed_node)
1566		return -ENOENT;
1567
1568	/*
1569	 * Since we have held i_mutex of this directory, it is impossible that
1570	 * a new directory index is added into the delayed node and index_cnt
1571	 * is updated now. So we needn't lock the delayed node.
1572	 */
1573	if (!delayed_node->index_cnt) {
1574		btrfs_release_delayed_node(delayed_node);
1575		return -EINVAL;
1576	}
1577
1578	BTRFS_I(inode)->index_cnt = delayed_node->index_cnt;
1579	btrfs_release_delayed_node(delayed_node);
1580	return 0;
1581}
1582
1583bool btrfs_readdir_get_delayed_items(struct inode *inode,
 
1584				     struct list_head *ins_list,
1585				     struct list_head *del_list)
1586{
1587	struct btrfs_delayed_node *delayed_node;
1588	struct btrfs_delayed_item *item;
1589
1590	delayed_node = btrfs_get_delayed_node(inode);
1591	if (!delayed_node)
1592		return false;
1593
1594	/*
1595	 * We can only do one readdir with delayed items at a time because of
1596	 * item->readdir_list.
1597	 */
1598	inode_unlock_shared(inode);
1599	inode_lock(inode);
1600
1601	mutex_lock(&delayed_node->mutex);
1602	item = __btrfs_first_delayed_insertion_item(delayed_node);
1603	while (item) {
1604		atomic_inc(&item->refs);
1605		list_add_tail(&item->readdir_list, ins_list);
1606		item = __btrfs_next_delayed_item(item);
1607	}
1608
1609	item = __btrfs_first_delayed_deletion_item(delayed_node);
1610	while (item) {
1611		atomic_inc(&item->refs);
1612		list_add_tail(&item->readdir_list, del_list);
1613		item = __btrfs_next_delayed_item(item);
1614	}
1615	mutex_unlock(&delayed_node->mutex);
1616	/*
1617	 * This delayed node is still cached in the btrfs inode, so refs
1618	 * must be > 1 now, and we needn't check it is going to be freed
1619	 * or not.
1620	 *
1621	 * Besides that, this function is used to read dir, we do not
1622	 * insert/delete delayed items in this period. So we also needn't
1623	 * requeue or dequeue this delayed node.
1624	 */
1625	atomic_dec(&delayed_node->refs);
1626
1627	return true;
1628}
1629
1630void btrfs_readdir_put_delayed_items(struct inode *inode,
1631				     struct list_head *ins_list,
1632				     struct list_head *del_list)
1633{
1634	struct btrfs_delayed_item *curr, *next;
1635
1636	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1637		list_del(&curr->readdir_list);
1638		if (atomic_dec_and_test(&curr->refs))
1639			kfree(curr);
1640	}
1641
1642	list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1643		list_del(&curr->readdir_list);
1644		if (atomic_dec_and_test(&curr->refs))
1645			kfree(curr);
1646	}
1647
1648	/*
1649	 * The VFS is going to do up_read(), so we need to downgrade back to a
1650	 * read lock.
1651	 */
1652	downgrade_write(&inode->i_rwsem);
1653}
1654
1655int btrfs_should_delete_dir_index(struct list_head *del_list,
1656				  u64 index)
1657{
1658	struct btrfs_delayed_item *curr, *next;
1659	int ret;
1660
1661	if (list_empty(del_list))
1662		return 0;
1663
1664	list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1665		if (curr->key.offset > index)
1666			break;
1667
1668		list_del(&curr->readdir_list);
1669		ret = (curr->key.offset == index);
1670
1671		if (atomic_dec_and_test(&curr->refs))
1672			kfree(curr);
1673
1674		if (ret)
1675			return 1;
1676		else
1677			continue;
1678	}
1679	return 0;
1680}
1681
1682/*
1683 * btrfs_readdir_delayed_dir_index - read dir info stored in the delayed tree
1684 *
1685 */
1686int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
1687				    struct list_head *ins_list)
1688{
1689	struct btrfs_dir_item *di;
1690	struct btrfs_delayed_item *curr, *next;
1691	struct btrfs_key location;
1692	char *name;
1693	int name_len;
1694	int over = 0;
1695	unsigned char d_type;
1696
1697	if (list_empty(ins_list))
1698		return 0;
1699
1700	/*
1701	 * Changing the data of the delayed item is impossible. So
1702	 * we needn't lock them. And we have held i_mutex of the
1703	 * directory, nobody can delete any directory indexes now.
1704	 */
1705	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1706		list_del(&curr->readdir_list);
1707
1708		if (curr->key.offset < ctx->pos) {
1709			if (atomic_dec_and_test(&curr->refs))
1710				kfree(curr);
1711			continue;
1712		}
1713
1714		ctx->pos = curr->key.offset;
1715
1716		di = (struct btrfs_dir_item *)curr->data;
1717		name = (char *)(di + 1);
1718		name_len = btrfs_stack_dir_name_len(di);
1719
1720		d_type = btrfs_filetype_table[di->type];
1721		btrfs_disk_key_to_cpu(&location, &di->location);
1722
1723		over = !dir_emit(ctx, name, name_len,
1724			       location.objectid, d_type);
1725
1726		if (atomic_dec_and_test(&curr->refs))
1727			kfree(curr);
1728
1729		if (over)
1730			return 1;
 
1731	}
1732	return 0;
1733}
1734
1735static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1736				  struct btrfs_inode_item *inode_item,
1737				  struct inode *inode)
1738{
 
 
1739	btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1740	btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1741	btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1742	btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1743	btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1744	btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1745	btrfs_set_stack_inode_generation(inode_item,
1746					 BTRFS_I(inode)->generation);
1747	btrfs_set_stack_inode_sequence(inode_item, inode->i_version);
 
1748	btrfs_set_stack_inode_transid(inode_item, trans->transid);
1749	btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1750	btrfs_set_stack_inode_flags(inode_item, BTRFS_I(inode)->flags);
 
 
1751	btrfs_set_stack_inode_block_group(inode_item, 0);
1752
1753	btrfs_set_stack_timespec_sec(&inode_item->atime,
1754				     inode->i_atime.tv_sec);
1755	btrfs_set_stack_timespec_nsec(&inode_item->atime,
1756				      inode->i_atime.tv_nsec);
1757
1758	btrfs_set_stack_timespec_sec(&inode_item->mtime,
1759				     inode->i_mtime.tv_sec);
1760	btrfs_set_stack_timespec_nsec(&inode_item->mtime,
1761				      inode->i_mtime.tv_nsec);
1762
1763	btrfs_set_stack_timespec_sec(&inode_item->ctime,
1764				     inode->i_ctime.tv_sec);
1765	btrfs_set_stack_timespec_nsec(&inode_item->ctime,
1766				      inode->i_ctime.tv_nsec);
1767
1768	btrfs_set_stack_timespec_sec(&inode_item->otime,
1769				     BTRFS_I(inode)->i_otime.tv_sec);
1770	btrfs_set_stack_timespec_nsec(&inode_item->otime,
1771				     BTRFS_I(inode)->i_otime.tv_nsec);
1772}
1773
1774int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1775{
 
1776	struct btrfs_delayed_node *delayed_node;
1777	struct btrfs_inode_item *inode_item;
1778
1779	delayed_node = btrfs_get_delayed_node(inode);
1780	if (!delayed_node)
1781		return -ENOENT;
1782
1783	mutex_lock(&delayed_node->mutex);
1784	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1785		mutex_unlock(&delayed_node->mutex);
1786		btrfs_release_delayed_node(delayed_node);
1787		return -ENOENT;
1788	}
1789
1790	inode_item = &delayed_node->inode_item;
1791
1792	i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1793	i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1794	btrfs_i_size_write(inode, btrfs_stack_inode_size(inode_item));
 
 
1795	inode->i_mode = btrfs_stack_inode_mode(inode_item);
1796	set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1797	inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1798	BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1799        BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
1800
1801	inode->i_version = btrfs_stack_inode_sequence(inode_item);
 
1802	inode->i_rdev = 0;
1803	*rdev = btrfs_stack_inode_rdev(inode_item);
1804	BTRFS_I(inode)->flags = btrfs_stack_inode_flags(inode_item);
 
1805
1806	inode->i_atime.tv_sec = btrfs_stack_timespec_sec(&inode_item->atime);
1807	inode->i_atime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->atime);
1808
1809	inode->i_mtime.tv_sec = btrfs_stack_timespec_sec(&inode_item->mtime);
1810	inode->i_mtime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->mtime);
1811
1812	inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(&inode_item->ctime);
1813	inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->ctime);
1814
1815	BTRFS_I(inode)->i_otime.tv_sec =
1816		btrfs_stack_timespec_sec(&inode_item->otime);
1817	BTRFS_I(inode)->i_otime.tv_nsec =
1818		btrfs_stack_timespec_nsec(&inode_item->otime);
1819
1820	inode->i_generation = BTRFS_I(inode)->generation;
1821	BTRFS_I(inode)->index_cnt = (u64)-1;
 
1822
1823	mutex_unlock(&delayed_node->mutex);
1824	btrfs_release_delayed_node(delayed_node);
1825	return 0;
1826}
1827
1828int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1829			       struct btrfs_root *root, struct inode *inode)
1830{
 
1831	struct btrfs_delayed_node *delayed_node;
1832	int ret = 0;
1833
1834	delayed_node = btrfs_get_or_create_delayed_node(inode);
1835	if (IS_ERR(delayed_node))
1836		return PTR_ERR(delayed_node);
1837
1838	mutex_lock(&delayed_node->mutex);
1839	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1840		fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
 
1841		goto release_node;
1842	}
1843
1844	ret = btrfs_delayed_inode_reserve_metadata(trans, root, inode,
1845						   delayed_node);
1846	if (ret)
1847		goto release_node;
1848
1849	fill_stack_inode_item(trans, &delayed_node->inode_item, inode);
1850	set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1851	delayed_node->count++;
1852	atomic_inc(&root->fs_info->delayed_root->items);
1853release_node:
1854	mutex_unlock(&delayed_node->mutex);
1855	btrfs_release_delayed_node(delayed_node);
1856	return ret;
1857}
1858
1859int btrfs_delayed_delete_inode_ref(struct inode *inode)
1860{
1861	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1862	struct btrfs_delayed_node *delayed_node;
1863
1864	/*
1865	 * we don't do delayed inode updates during log recovery because it
1866	 * leads to enospc problems.  This means we also can't do
1867	 * delayed inode refs
1868	 */
1869	if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
1870		return -EAGAIN;
1871
1872	delayed_node = btrfs_get_or_create_delayed_node(inode);
1873	if (IS_ERR(delayed_node))
1874		return PTR_ERR(delayed_node);
1875
1876	/*
1877	 * We don't reserve space for inode ref deletion is because:
1878	 * - We ONLY do async inode ref deletion for the inode who has only
1879	 *   one link(i_nlink == 1), it means there is only one inode ref.
1880	 *   And in most case, the inode ref and the inode item are in the
1881	 *   same leaf, and we will deal with them at the same time.
1882	 *   Since we are sure we will reserve the space for the inode item,
1883	 *   it is unnecessary to reserve space for inode ref deletion.
1884	 * - If the inode ref and the inode item are not in the same leaf,
1885	 *   We also needn't worry about enospc problem, because we reserve
1886	 *   much more space for the inode update than it needs.
1887	 * - At the worst, we can steal some space from the global reservation.
1888	 *   It is very rare.
1889	 */
1890	mutex_lock(&delayed_node->mutex);
1891	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1892		goto release_node;
1893
1894	set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1895	delayed_node->count++;
1896	atomic_inc(&fs_info->delayed_root->items);
1897release_node:
1898	mutex_unlock(&delayed_node->mutex);
1899	btrfs_release_delayed_node(delayed_node);
1900	return 0;
1901}
1902
1903static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
1904{
1905	struct btrfs_root *root = delayed_node->root;
1906	struct btrfs_fs_info *fs_info = root->fs_info;
1907	struct btrfs_delayed_item *curr_item, *prev_item;
1908
1909	mutex_lock(&delayed_node->mutex);
1910	curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
1911	while (curr_item) {
1912		btrfs_delayed_item_release_metadata(fs_info, curr_item);
1913		prev_item = curr_item;
1914		curr_item = __btrfs_next_delayed_item(prev_item);
1915		btrfs_release_delayed_item(prev_item);
1916	}
1917
 
 
 
 
 
 
1918	curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
1919	while (curr_item) {
1920		btrfs_delayed_item_release_metadata(fs_info, curr_item);
1921		prev_item = curr_item;
1922		curr_item = __btrfs_next_delayed_item(prev_item);
1923		btrfs_release_delayed_item(prev_item);
1924	}
1925
1926	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1927		btrfs_release_delayed_iref(delayed_node);
1928
1929	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1930		btrfs_delayed_inode_release_metadata(fs_info, delayed_node);
1931		btrfs_release_delayed_inode(delayed_node);
1932	}
1933	mutex_unlock(&delayed_node->mutex);
1934}
1935
1936void btrfs_kill_delayed_inode_items(struct inode *inode)
1937{
1938	struct btrfs_delayed_node *delayed_node;
1939
1940	delayed_node = btrfs_get_delayed_node(inode);
1941	if (!delayed_node)
1942		return;
1943
1944	__btrfs_kill_delayed_node(delayed_node);
1945	btrfs_release_delayed_node(delayed_node);
1946}
1947
1948void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
1949{
1950	u64 inode_id = 0;
1951	struct btrfs_delayed_node *delayed_nodes[8];
1952	int i, n;
1953
1954	while (1) {
1955		spin_lock(&root->inode_lock);
1956		n = radix_tree_gang_lookup(&root->delayed_nodes_tree,
1957					   (void **)delayed_nodes, inode_id,
1958					   ARRAY_SIZE(delayed_nodes));
1959		if (!n) {
1960			spin_unlock(&root->inode_lock);
1961			break;
1962		}
1963
1964		inode_id = delayed_nodes[n - 1]->inode_id + 1;
 
 
 
 
1965
1966		for (i = 0; i < n; i++)
1967			atomic_inc(&delayed_nodes[i]->refs);
1968		spin_unlock(&root->inode_lock);
 
 
 
 
 
 
 
 
 
 
 
 
1969
1970		for (i = 0; i < n; i++) {
1971			__btrfs_kill_delayed_node(delayed_nodes[i]);
1972			btrfs_release_delayed_node(delayed_nodes[i]);
1973		}
1974	}
1975}
1976
1977void btrfs_destroy_delayed_inodes(struct btrfs_fs_info *fs_info)
1978{
1979	struct btrfs_delayed_node *curr_node, *prev_node;
1980
1981	curr_node = btrfs_first_delayed_node(fs_info->delayed_root);
1982	while (curr_node) {
1983		__btrfs_kill_delayed_node(curr_node);
1984
1985		prev_node = curr_node;
1986		curr_node = btrfs_next_delayed_node(curr_node);
1987		btrfs_release_delayed_node(prev_node);
1988	}
1989}
1990
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2011 Fujitsu.  All rights reserved.
   4 * Written by Miao Xie <miaox@cn.fujitsu.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   5 */
   6
   7#include <linux/slab.h>
   8#include <linux/iversion.h>
   9#include "ctree.h"
  10#include "fs.h"
  11#include "messages.h"
  12#include "misc.h"
  13#include "delayed-inode.h"
  14#include "disk-io.h"
  15#include "transaction.h"
  16#include "qgroup.h"
  17#include "locking.h"
  18#include "inode-item.h"
  19#include "space-info.h"
  20#include "accessors.h"
  21#include "file-item.h"
  22
  23#define BTRFS_DELAYED_WRITEBACK		512
  24#define BTRFS_DELAYED_BACKGROUND	128
  25#define BTRFS_DELAYED_BATCH		16
  26
  27static struct kmem_cache *delayed_node_cache;
  28
  29int __init btrfs_delayed_inode_init(void)
  30{
  31	delayed_node_cache = KMEM_CACHE(btrfs_delayed_node, 0);
 
 
 
 
  32	if (!delayed_node_cache)
  33		return -ENOMEM;
  34	return 0;
  35}
  36
  37void __cold btrfs_delayed_inode_exit(void)
  38{
  39	kmem_cache_destroy(delayed_node_cache);
  40}
  41
  42void btrfs_init_delayed_root(struct btrfs_delayed_root *delayed_root)
  43{
  44	atomic_set(&delayed_root->items, 0);
  45	atomic_set(&delayed_root->items_seq, 0);
  46	delayed_root->nodes = 0;
  47	spin_lock_init(&delayed_root->lock);
  48	init_waitqueue_head(&delayed_root->wait);
  49	INIT_LIST_HEAD(&delayed_root->node_list);
  50	INIT_LIST_HEAD(&delayed_root->prepare_list);
  51}
  52
  53static inline void btrfs_init_delayed_node(
  54				struct btrfs_delayed_node *delayed_node,
  55				struct btrfs_root *root, u64 inode_id)
  56{
  57	delayed_node->root = root;
  58	delayed_node->inode_id = inode_id;
  59	refcount_set(&delayed_node->refs, 0);
  60	delayed_node->ins_root = RB_ROOT_CACHED;
  61	delayed_node->del_root = RB_ROOT_CACHED;
  62	mutex_init(&delayed_node->mutex);
  63	INIT_LIST_HEAD(&delayed_node->n_list);
  64	INIT_LIST_HEAD(&delayed_node->p_list);
  65}
  66
  67static struct btrfs_delayed_node *btrfs_get_delayed_node(
  68		struct btrfs_inode *btrfs_inode)
 
 
 
 
 
 
 
 
 
 
 
  69{
 
  70	struct btrfs_root *root = btrfs_inode->root;
  71	u64 ino = btrfs_ino(btrfs_inode);
  72	struct btrfs_delayed_node *node;
  73
  74	node = READ_ONCE(btrfs_inode->delayed_node);
  75	if (node) {
  76		refcount_inc(&node->refs);
  77		return node;
  78	}
  79
  80	xa_lock(&root->delayed_nodes);
  81	node = xa_load(&root->delayed_nodes, ino);
  82
  83	if (node) {
  84		if (btrfs_inode->delayed_node) {
  85			refcount_inc(&node->refs);	/* can be accessed */
  86			BUG_ON(btrfs_inode->delayed_node != node);
  87			xa_unlock(&root->delayed_nodes);
  88			return node;
  89		}
  90
  91		/*
  92		 * It's possible that we're racing into the middle of removing
  93		 * this node from the xarray.  In this case, the refcount
  94		 * was zero and it should never go back to one.  Just return
  95		 * NULL like it was never in the xarray at all; our release
  96		 * function is in the process of removing it.
  97		 *
  98		 * Some implementations of refcount_inc refuse to bump the
  99		 * refcount once it has hit zero.  If we don't do this dance
 100		 * here, refcount_inc() may decide to just WARN_ONCE() instead
 101		 * of actually bumping the refcount.
 102		 *
 103		 * If this node is properly in the xarray, we want to bump the
 104		 * refcount twice, once for the inode and once for this get
 105		 * operation.
 106		 */
 107		if (refcount_inc_not_zero(&node->refs)) {
 108			refcount_inc(&node->refs);
 109			btrfs_inode->delayed_node = node;
 110		} else {
 111			node = NULL;
 112		}
 113
 114		xa_unlock(&root->delayed_nodes);
 115		return node;
 116	}
 117	xa_unlock(&root->delayed_nodes);
 118
 119	return NULL;
 120}
 121
 122/* Will return either the node or PTR_ERR(-ENOMEM) */
 123static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
 124		struct btrfs_inode *btrfs_inode)
 125{
 126	struct btrfs_delayed_node *node;
 
 127	struct btrfs_root *root = btrfs_inode->root;
 128	u64 ino = btrfs_ino(btrfs_inode);
 129	int ret;
 130	void *ptr;
 131
 132again:
 133	node = btrfs_get_delayed_node(btrfs_inode);
 134	if (node)
 135		return node;
 136
 137	node = kmem_cache_zalloc(delayed_node_cache, GFP_NOFS);
 138	if (!node)
 139		return ERR_PTR(-ENOMEM);
 140	btrfs_init_delayed_node(node, root, ino);
 141
 142	/* Cached in the inode and can be accessed. */
 143	refcount_set(&node->refs, 2);
 144
 145	/* Allocate and reserve the slot, from now it can return a NULL from xa_load(). */
 146	ret = xa_reserve(&root->delayed_nodes, ino, GFP_NOFS);
 147	if (ret == -ENOMEM) {
 148		kmem_cache_free(delayed_node_cache, node);
 149		return ERR_PTR(-ENOMEM);
 150	}
 151	xa_lock(&root->delayed_nodes);
 152	ptr = xa_load(&root->delayed_nodes, ino);
 153	if (ptr) {
 154		/* Somebody inserted it, go back and read it. */
 155		xa_unlock(&root->delayed_nodes);
 156		kmem_cache_free(delayed_node_cache, node);
 157		node = NULL;
 158		goto again;
 159	}
 160	ptr = __xa_store(&root->delayed_nodes, ino, node, GFP_ATOMIC);
 161	ASSERT(xa_err(ptr) != -EINVAL);
 162	ASSERT(xa_err(ptr) != -ENOMEM);
 163	ASSERT(ptr == NULL);
 164	btrfs_inode->delayed_node = node;
 165	xa_unlock(&root->delayed_nodes);
 
 166
 167	return node;
 168}
 169
 170/*
 171 * Call it when holding delayed_node->mutex
 172 *
 173 * If mod = 1, add this node into the prepared list.
 174 */
 175static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
 176				     struct btrfs_delayed_node *node,
 177				     int mod)
 178{
 179	spin_lock(&root->lock);
 180	if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 181		if (!list_empty(&node->p_list))
 182			list_move_tail(&node->p_list, &root->prepare_list);
 183		else if (mod)
 184			list_add_tail(&node->p_list, &root->prepare_list);
 185	} else {
 186		list_add_tail(&node->n_list, &root->node_list);
 187		list_add_tail(&node->p_list, &root->prepare_list);
 188		refcount_inc(&node->refs);	/* inserted into list */
 189		root->nodes++;
 190		set_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 191	}
 192	spin_unlock(&root->lock);
 193}
 194
 195/* Call it when holding delayed_node->mutex */
 196static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
 197				       struct btrfs_delayed_node *node)
 198{
 199	spin_lock(&root->lock);
 200	if (test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 201		root->nodes--;
 202		refcount_dec(&node->refs);	/* not in the list */
 203		list_del_init(&node->n_list);
 204		if (!list_empty(&node->p_list))
 205			list_del_init(&node->p_list);
 206		clear_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags);
 207	}
 208	spin_unlock(&root->lock);
 209}
 210
 211static struct btrfs_delayed_node *btrfs_first_delayed_node(
 212			struct btrfs_delayed_root *delayed_root)
 213{
 214	struct list_head *p;
 215	struct btrfs_delayed_node *node = NULL;
 216
 217	spin_lock(&delayed_root->lock);
 218	if (list_empty(&delayed_root->node_list))
 219		goto out;
 220
 221	p = delayed_root->node_list.next;
 222	node = list_entry(p, struct btrfs_delayed_node, n_list);
 223	refcount_inc(&node->refs);
 224out:
 225	spin_unlock(&delayed_root->lock);
 226
 227	return node;
 228}
 229
 230static struct btrfs_delayed_node *btrfs_next_delayed_node(
 231						struct btrfs_delayed_node *node)
 232{
 233	struct btrfs_delayed_root *delayed_root;
 234	struct list_head *p;
 235	struct btrfs_delayed_node *next = NULL;
 236
 237	delayed_root = node->root->fs_info->delayed_root;
 238	spin_lock(&delayed_root->lock);
 239	if (!test_bit(BTRFS_DELAYED_NODE_IN_LIST, &node->flags)) {
 240		/* not in the list */
 241		if (list_empty(&delayed_root->node_list))
 242			goto out;
 243		p = delayed_root->node_list.next;
 244	} else if (list_is_last(&node->n_list, &delayed_root->node_list))
 245		goto out;
 246	else
 247		p = node->n_list.next;
 248
 249	next = list_entry(p, struct btrfs_delayed_node, n_list);
 250	refcount_inc(&next->refs);
 251out:
 252	spin_unlock(&delayed_root->lock);
 253
 254	return next;
 255}
 256
 257static void __btrfs_release_delayed_node(
 258				struct btrfs_delayed_node *delayed_node,
 259				int mod)
 260{
 261	struct btrfs_delayed_root *delayed_root;
 262
 263	if (!delayed_node)
 264		return;
 265
 266	delayed_root = delayed_node->root->fs_info->delayed_root;
 267
 268	mutex_lock(&delayed_node->mutex);
 269	if (delayed_node->count)
 270		btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
 271	else
 272		btrfs_dequeue_delayed_node(delayed_root, delayed_node);
 273	mutex_unlock(&delayed_node->mutex);
 274
 275	if (refcount_dec_and_test(&delayed_node->refs)) {
 
 276		struct btrfs_root *root = delayed_node->root;
 277
 278		xa_erase(&root->delayed_nodes, delayed_node->inode_id);
 279		/*
 280		 * Once our refcount goes to zero, nobody is allowed to bump it
 281		 * back up.  We can delete it now.
 282		 */
 283		ASSERT(refcount_read(&delayed_node->refs) == 0);
 284		kmem_cache_free(delayed_node_cache, delayed_node);
 
 285	}
 286}
 287
 288static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
 289{
 290	__btrfs_release_delayed_node(node, 0);
 291}
 292
 293static struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
 294					struct btrfs_delayed_root *delayed_root)
 295{
 296	struct list_head *p;
 297	struct btrfs_delayed_node *node = NULL;
 298
 299	spin_lock(&delayed_root->lock);
 300	if (list_empty(&delayed_root->prepare_list))
 301		goto out;
 302
 303	p = delayed_root->prepare_list.next;
 304	list_del_init(p);
 305	node = list_entry(p, struct btrfs_delayed_node, p_list);
 306	refcount_inc(&node->refs);
 307out:
 308	spin_unlock(&delayed_root->lock);
 309
 310	return node;
 311}
 312
 313static inline void btrfs_release_prepared_delayed_node(
 314					struct btrfs_delayed_node *node)
 315{
 316	__btrfs_release_delayed_node(node, 1);
 317}
 318
 319static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u16 data_len,
 320					   struct btrfs_delayed_node *node,
 321					   enum btrfs_delayed_item_type type)
 322{
 323	struct btrfs_delayed_item *item;
 324
 325	item = kmalloc(struct_size(item, data, data_len), GFP_NOFS);
 326	if (item) {
 327		item->data_len = data_len;
 328		item->type = type;
 329		item->bytes_reserved = 0;
 330		item->delayed_node = node;
 331		RB_CLEAR_NODE(&item->rb_node);
 332		INIT_LIST_HEAD(&item->log_list);
 333		item->logged = false;
 334		refcount_set(&item->refs, 1);
 335	}
 336	return item;
 337}
 338
 339/*
 340 * Look up the delayed item by key.
 341 *
 342 * @delayed_node: pointer to the delayed node
 343 * @index:	  the dir index value to lookup (offset of a dir index key)
 
 
 344 *
 345 * Note: if we don't find the right item, we will return the prev item and
 346 * the next item.
 347 */
 348static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
 349				struct rb_root *root,
 350				u64 index)
 
 
 351{
 352	struct rb_node *node = root->rb_node;
 353	struct btrfs_delayed_item *delayed_item = NULL;
 
 
 
 354
 355	while (node) {
 356		delayed_item = rb_entry(node, struct btrfs_delayed_item,
 357					rb_node);
 358		if (delayed_item->index < index)
 
 
 359			node = node->rb_right;
 360		else if (delayed_item->index > index)
 361			node = node->rb_left;
 362		else
 363			return delayed_item;
 364	}
 365
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 366	return NULL;
 367}
 368
 
 
 
 
 
 
 
 
 369static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
 370				    struct btrfs_delayed_item *ins)
 
 371{
 372	struct rb_node **p, *node;
 373	struct rb_node *parent_node = NULL;
 374	struct rb_root_cached *root;
 375	struct btrfs_delayed_item *item;
 376	bool leftmost = true;
 377
 378	if (ins->type == BTRFS_DELAYED_INSERTION_ITEM)
 379		root = &delayed_node->ins_root;
 
 
 380	else
 381		root = &delayed_node->del_root;
 382
 383	p = &root->rb_root.rb_node;
 384	node = &ins->rb_node;
 385
 386	while (*p) {
 387		parent_node = *p;
 388		item = rb_entry(parent_node, struct btrfs_delayed_item,
 389				 rb_node);
 390
 391		if (item->index < ins->index) {
 
 392			p = &(*p)->rb_right;
 393			leftmost = false;
 394		} else if (item->index > ins->index) {
 395			p = &(*p)->rb_left;
 396		} else {
 397			return -EEXIST;
 398		}
 399	}
 400
 401	rb_link_node(node, parent_node, p);
 402	rb_insert_color_cached(node, root, leftmost);
 403
 404	if (ins->type == BTRFS_DELAYED_INSERTION_ITEM &&
 405	    ins->index >= delayed_node->index_cnt)
 406		delayed_node->index_cnt = ins->index + 1;
 
 
 
 407
 408	delayed_node->count++;
 409	atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
 410	return 0;
 411}
 412
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 413static void finish_one_item(struct btrfs_delayed_root *delayed_root)
 414{
 415	int seq = atomic_inc_return(&delayed_root->items_seq);
 416
 417	/* atomic_dec_return implies a barrier */
 
 
 418	if ((atomic_dec_return(&delayed_root->items) <
 419	    BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0))
 420		cond_wake_up_nomb(&delayed_root->wait);
 
 421}
 422
 423static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
 424{
 425	struct btrfs_delayed_node *delayed_node = delayed_item->delayed_node;
 426	struct rb_root_cached *root;
 427	struct btrfs_delayed_root *delayed_root;
 428
 429	/* Not inserted, ignore it. */
 430	if (RB_EMPTY_NODE(&delayed_item->rb_node))
 431		return;
 432
 433	/* If it's in a rbtree, then we need to have delayed node locked. */
 434	lockdep_assert_held(&delayed_node->mutex);
 435
 436	delayed_root = delayed_node->root->fs_info->delayed_root;
 
 
 437
 438	if (delayed_item->type == BTRFS_DELAYED_INSERTION_ITEM)
 439		root = &delayed_node->ins_root;
 440	else
 441		root = &delayed_node->del_root;
 442
 443	rb_erase_cached(&delayed_item->rb_node, root);
 444	RB_CLEAR_NODE(&delayed_item->rb_node);
 445	delayed_node->count--;
 446
 447	finish_one_item(delayed_root);
 448}
 449
 450static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
 451{
 452	if (item) {
 453		__btrfs_remove_delayed_item(item);
 454		if (refcount_dec_and_test(&item->refs))
 455			kfree(item);
 456	}
 457}
 458
 459static struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
 460					struct btrfs_delayed_node *delayed_node)
 461{
 462	struct rb_node *p;
 463	struct btrfs_delayed_item *item = NULL;
 464
 465	p = rb_first_cached(&delayed_node->ins_root);
 466	if (p)
 467		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 468
 469	return item;
 470}
 471
 472static struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
 473					struct btrfs_delayed_node *delayed_node)
 474{
 475	struct rb_node *p;
 476	struct btrfs_delayed_item *item = NULL;
 477
 478	p = rb_first_cached(&delayed_node->del_root);
 479	if (p)
 480		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
 481
 482	return item;
 483}
 484
 485static struct btrfs_delayed_item *__btrfs_next_delayed_item(
 486						struct btrfs_delayed_item *item)
 487{
 488	struct rb_node *p;
 489	struct btrfs_delayed_item *next = NULL;
 490
 491	p = rb_next(&item->rb_node);
 492	if (p)
 493		next = rb_entry(p, struct btrfs_delayed_item, rb_node);
 494
 495	return next;
 496}
 497
 498static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 
 499					       struct btrfs_delayed_item *item)
 500{
 501	struct btrfs_block_rsv *src_rsv;
 502	struct btrfs_block_rsv *dst_rsv;
 503	struct btrfs_fs_info *fs_info = trans->fs_info;
 504	u64 num_bytes;
 505	int ret;
 506
 507	if (!trans->bytes_reserved)
 508		return 0;
 509
 510	src_rsv = trans->block_rsv;
 511	dst_rsv = &fs_info->delayed_block_rsv;
 512
 513	num_bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
 514
 515	/*
 516	 * Here we migrate space rsv from transaction rsv, since have already
 517	 * reserved space when starting a transaction.  So no need to reserve
 518	 * qgroup space here.
 519	 */
 520	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, true);
 521	if (!ret) {
 522		trace_btrfs_space_reservation(fs_info, "delayed_item",
 523					      item->delayed_node->inode_id,
 524					      num_bytes, 1);
 525		/*
 526		 * For insertions we track reserved metadata space by accounting
 527		 * for the number of leaves that will be used, based on the delayed
 528		 * node's curr_index_batch_size and index_item_leaves fields.
 529		 */
 530		if (item->type == BTRFS_DELAYED_DELETION_ITEM)
 531			item->bytes_reserved = num_bytes;
 532	}
 533
 534	return ret;
 535}
 536
 537static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
 538						struct btrfs_delayed_item *item)
 539{
 540	struct btrfs_block_rsv *rsv;
 541	struct btrfs_fs_info *fs_info = root->fs_info;
 542
 543	if (!item->bytes_reserved)
 544		return;
 545
 546	rsv = &fs_info->delayed_block_rsv;
 547	/*
 548	 * Check btrfs_delayed_item_reserve_metadata() to see why we don't need
 549	 * to release/reserve qgroup space.
 550	 */
 551	trace_btrfs_space_reservation(fs_info, "delayed_item",
 552				      item->delayed_node->inode_id,
 553				      item->bytes_reserved, 0);
 554	btrfs_block_rsv_release(fs_info, rsv, item->bytes_reserved, NULL);
 555}
 556
 557static void btrfs_delayed_item_release_leaves(struct btrfs_delayed_node *node,
 558					      unsigned int num_leaves)
 559{
 560	struct btrfs_fs_info *fs_info = node->root->fs_info;
 561	const u64 bytes = btrfs_calc_insert_metadata_size(fs_info, num_leaves);
 562
 563	/* There are no space reservations during log replay, bail out. */
 564	if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
 565		return;
 566
 567	trace_btrfs_space_reservation(fs_info, "delayed_item", node->inode_id,
 568				      bytes, 0);
 569	btrfs_block_rsv_release(fs_info, &fs_info->delayed_block_rsv, bytes, NULL);
 570}
 571
 572static int btrfs_delayed_inode_reserve_metadata(
 573					struct btrfs_trans_handle *trans,
 574					struct btrfs_root *root,
 
 575					struct btrfs_delayed_node *node)
 576{
 577	struct btrfs_fs_info *fs_info = root->fs_info;
 578	struct btrfs_block_rsv *src_rsv;
 579	struct btrfs_block_rsv *dst_rsv;
 580	u64 num_bytes;
 581	int ret;
 
 582
 583	src_rsv = trans->block_rsv;
 584	dst_rsv = &fs_info->delayed_block_rsv;
 585
 586	num_bytes = btrfs_calc_metadata_size(fs_info, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 587
 588	/*
 589	 * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 590	 * which doesn't reserve space for speed.  This is a problem since we
 591	 * still need to reserve space for this update, so try to reserve the
 592	 * space.
 593	 *
 594	 * Now if src_rsv == delalloc_block_rsv we'll let it just steal since
 595	 * we always reserve enough to update the inode item.
 596	 */
 597	if (!src_rsv || (!trans->bytes_reserved &&
 598			 src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
 599		ret = btrfs_qgroup_reserve_meta(root, num_bytes,
 600					  BTRFS_QGROUP_RSV_META_PREALLOC, true);
 601		if (ret < 0)
 602			return ret;
 603		ret = btrfs_block_rsv_add(fs_info, dst_rsv, num_bytes,
 604					  BTRFS_RESERVE_NO_FLUSH);
 605		/* NO_FLUSH could only fail with -ENOSPC */
 606		ASSERT(ret == 0 || ret == -ENOSPC);
 607		if (ret)
 608			btrfs_qgroup_free_meta_prealloc(root, num_bytes);
 609	} else {
 610		ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, true);
 
 
 
 
 
 
 
 
 
 
 611	}
 612
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 613	if (!ret) {
 614		trace_btrfs_space_reservation(fs_info, "delayed_inode",
 615					      node->inode_id, num_bytes, 1);
 616		node->bytes_reserved = num_bytes;
 617	}
 618
 
 
 
 
 
 
 619	return ret;
 620}
 621
 622static void btrfs_delayed_inode_release_metadata(struct btrfs_fs_info *fs_info,
 623						struct btrfs_delayed_node *node,
 624						bool qgroup_free)
 625{
 626	struct btrfs_block_rsv *rsv;
 627
 628	if (!node->bytes_reserved)
 629		return;
 630
 631	rsv = &fs_info->delayed_block_rsv;
 632	trace_btrfs_space_reservation(fs_info, "delayed_inode",
 633				      node->inode_id, node->bytes_reserved, 0);
 634	btrfs_block_rsv_release(fs_info, rsv, node->bytes_reserved, NULL);
 635	if (qgroup_free)
 636		btrfs_qgroup_free_meta_prealloc(node->root,
 637				node->bytes_reserved);
 638	else
 639		btrfs_qgroup_convert_reserved_meta(node->root,
 640				node->bytes_reserved);
 641	node->bytes_reserved = 0;
 642}
 643
 644/*
 645 * Insert a single delayed item or a batch of delayed items, as many as possible
 646 * that fit in a leaf. The delayed items (dir index keys) are sorted by their key
 647 * in the rbtree, and if there's a gap between two consecutive dir index items,
 648 * then it means at some point we had delayed dir indexes to add but they got
 649 * removed (by btrfs_delete_delayed_dir_index()) before we attempted to flush them
 650 * into the subvolume tree. Dir index keys also have their offsets coming from a
 651 * monotonically increasing counter, so we can't get new keys with an offset that
 652 * fits within a gap between delayed dir index items.
 653 */
 654static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
 655				     struct btrfs_root *root,
 656				     struct btrfs_path *path,
 657				     struct btrfs_delayed_item *first_item)
 658{
 659	struct btrfs_fs_info *fs_info = root->fs_info;
 660	struct btrfs_delayed_node *node = first_item->delayed_node;
 661	LIST_HEAD(item_list);
 662	struct btrfs_delayed_item *curr;
 663	struct btrfs_delayed_item *next;
 664	const int max_size = BTRFS_LEAF_DATA_SIZE(fs_info);
 665	struct btrfs_item_batch batch;
 666	struct btrfs_key first_key;
 667	const u32 first_data_size = first_item->data_len;
 668	int total_size;
 669	char *ins_data = NULL;
 670	int ret;
 671	bool continuous_keys_only = false;
 
 
 672
 673	lockdep_assert_held(&node->mutex);
 
 
 674
 675	/*
 676	 * During normal operation the delayed index offset is continuously
 677	 * increasing, so we can batch insert all items as there will not be any
 678	 * overlapping keys in the tree.
 679	 *
 680	 * The exception to this is log replay, where we may have interleaved
 681	 * offsets in the tree, so our batch needs to be continuous keys only in
 682	 * order to ensure we do not end up with out of order items in our leaf.
 683	 */
 684	if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
 685		continuous_keys_only = true;
 686
 687	/*
 688	 * For delayed items to insert, we track reserved metadata bytes based
 689	 * on the number of leaves that we will use.
 690	 * See btrfs_insert_delayed_dir_index() and
 691	 * btrfs_delayed_item_reserve_metadata()).
 692	 */
 693	ASSERT(first_item->bytes_reserved == 0);
 694
 695	list_add_tail(&first_item->tree_list, &item_list);
 696	batch.total_data_size = first_data_size;
 697	batch.nr = 1;
 698	total_size = first_data_size + sizeof(struct btrfs_item);
 699	curr = first_item;
 700
 701	while (true) {
 702		int next_size;
 703
 
 704		next = __btrfs_next_delayed_item(curr);
 705		if (!next)
 706			break;
 707
 708		/*
 709		 * We cannot allow gaps in the key space if we're doing log
 710		 * replay.
 711		 */
 712		if (continuous_keys_only && (next->index != curr->index + 1))
 713			break;
 
 714
 715		ASSERT(next->bytes_reserved == 0);
 
 
 
 716
 717		next_size = next->data_len + sizeof(struct btrfs_item);
 718		if (total_size + next_size > max_size)
 719			break;
 
 
 
 720
 721		list_add_tail(&next->tree_list, &item_list);
 722		batch.nr++;
 723		total_size += next_size;
 724		batch.total_data_size += next->data_len;
 725		curr = next;
 726	}
 727
 728	if (batch.nr == 1) {
 729		first_key.objectid = node->inode_id;
 730		first_key.type = BTRFS_DIR_INDEX_KEY;
 731		first_key.offset = first_item->index;
 732		batch.keys = &first_key;
 733		batch.data_sizes = &first_data_size;
 734	} else {
 735		struct btrfs_key *ins_keys;
 736		u32 *ins_sizes;
 737		int i = 0;
 738
 739		ins_data = kmalloc(batch.nr * sizeof(u32) +
 740				   batch.nr * sizeof(struct btrfs_key), GFP_NOFS);
 741		if (!ins_data) {
 742			ret = -ENOMEM;
 743			goto out;
 744		}
 745		ins_sizes = (u32 *)ins_data;
 746		ins_keys = (struct btrfs_key *)(ins_data + batch.nr * sizeof(u32));
 747		batch.keys = ins_keys;
 748		batch.data_sizes = ins_sizes;
 749		list_for_each_entry(curr, &item_list, tree_list) {
 750			ins_keys[i].objectid = node->inode_id;
 751			ins_keys[i].type = BTRFS_DIR_INDEX_KEY;
 752			ins_keys[i].offset = curr->index;
 753			ins_sizes[i] = curr->data_len;
 754			i++;
 755		}
 756	}
 757
 758	ret = btrfs_insert_empty_items(trans, root, path, &batch);
 759	if (ret)
 760		goto out;
 761
 762	list_for_each_entry(curr, &item_list, tree_list) {
 763		char *data_ptr;
 
 764
 765		data_ptr = btrfs_item_ptr(path->nodes[0], path->slots[0], char);
 766		write_extent_buffer(path->nodes[0], &curr->data,
 767				    (unsigned long)data_ptr, curr->data_len);
 768		path->slots[0]++;
 769	}
 770
 771	/*
 772	 * Now release our path before releasing the delayed items and their
 773	 * metadata reservations, so that we don't block other tasks for more
 774	 * time than needed.
 775	 */
 776	btrfs_release_path(path);
 777
 778	ASSERT(node->index_item_leaves > 0);
 
 
 
 
 
 
 
 779
 780	/*
 781	 * For normal operations we will batch an entire leaf's worth of delayed
 782	 * items, so if there are more items to process we can decrement
 783	 * index_item_leaves by 1 as we inserted 1 leaf's worth of items.
 784	 *
 785	 * However for log replay we may not have inserted an entire leaf's
 786	 * worth of items, we may have not had continuous items, so decrementing
 787	 * here would mess up the index_item_leaves accounting.  For this case
 788	 * only clean up the accounting when there are no items left.
 789	 */
 790	if (next && !continuous_keys_only) {
 791		/*
 792		 * We inserted one batch of items into a leaf a there are more
 793		 * items to flush in a future batch, now release one unit of
 794		 * metadata space from the delayed block reserve, corresponding
 795		 * the leaf we just flushed to.
 796		 */
 797		btrfs_delayed_item_release_leaves(node, 1);
 798		node->index_item_leaves--;
 799	} else if (!next) {
 800		/*
 801		 * There are no more items to insert. We can have a number of
 802		 * reserved leaves > 1 here - this happens when many dir index
 803		 * items are added and then removed before they are flushed (file
 804		 * names with a very short life, never span a transaction). So
 805		 * release all remaining leaves.
 806		 */
 807		btrfs_delayed_item_release_leaves(node, node->index_item_leaves);
 808		node->index_item_leaves = 0;
 809	}
 810
 811	list_for_each_entry_safe(curr, next, &item_list, tree_list) {
 812		list_del(&curr->tree_list);
 813		btrfs_release_delayed_item(curr);
 814	}
 
 
 
 
 815out:
 816	kfree(ins_data);
 817	return ret;
 818}
 819
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 820static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
 821				      struct btrfs_path *path,
 822				      struct btrfs_root *root,
 823				      struct btrfs_delayed_node *node)
 824{
 
 825	int ret = 0;
 826
 827	while (ret == 0) {
 828		struct btrfs_delayed_item *curr;
 
 
 
 
 
 
 
 
 
 829
 830		mutex_lock(&node->mutex);
 831		curr = __btrfs_first_delayed_insertion_item(node);
 832		if (!curr) {
 833			mutex_unlock(&node->mutex);
 834			break;
 835		}
 836		ret = btrfs_insert_delayed_item(trans, root, path, curr);
 837		mutex_unlock(&node->mutex);
 838	}
 
 
 
 
 
 
 839
 
 
 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	const u64 ino = item->delayed_node->inode_id;
 849	struct btrfs_fs_info *fs_info = root->fs_info;
 850	struct btrfs_delayed_item *curr, *next;
 851	struct extent_buffer *leaf = path->nodes[0];
 852	LIST_HEAD(batch_list);
 853	int nitems, slot, last_slot;
 854	int ret;
 855	u64 total_reserved_size = item->bytes_reserved;
 856
 857	ASSERT(leaf != NULL);
 858
 859	slot = path->slots[0];
 860	last_slot = btrfs_header_nritems(leaf) - 1;
 861	/*
 862	 * Our caller always gives us a path pointing to an existing item, so
 863	 * this can not happen.
 864	 */
 865	ASSERT(slot <= last_slot);
 866	if (WARN_ON(slot > last_slot))
 867		return -ENOENT;
 868
 869	nitems = 1;
 870	curr = item;
 871	list_add_tail(&curr->tree_list, &batch_list);
 872
 
 
 
 
 
 
 
 
 
 873	/*
 874	 * Keep checking if the next delayed item matches the next item in the
 875	 * leaf - if so, we can add it to the batch of items to delete from the
 876	 * leaf.
 877	 */
 878	while (slot < last_slot) {
 879		struct btrfs_key key;
 
 880
 
 881		next = __btrfs_next_delayed_item(curr);
 882		if (!next)
 883			break;
 884
 885		slot++;
 886		btrfs_item_key_to_cpu(leaf, &key, slot);
 887		if (key.objectid != ino ||
 888		    key.type != BTRFS_DIR_INDEX_KEY ||
 889		    key.offset != next->index)
 890			break;
 891		nitems++;
 892		curr = next;
 893		list_add_tail(&curr->tree_list, &batch_list);
 894		total_reserved_size += curr->bytes_reserved;
 895	}
 896
 
 
 
 897	ret = btrfs_del_items(trans, root, path, path->slots[0], nitems);
 898	if (ret)
 899		return ret;
 900
 901	/* In case of BTRFS_FS_LOG_RECOVERING items won't have reserved space */
 902	if (total_reserved_size > 0) {
 903		/*
 904		 * Check btrfs_delayed_item_reserve_metadata() to see why we
 905		 * don't need to release/reserve qgroup space.
 906		 */
 907		trace_btrfs_space_reservation(fs_info, "delayed_item", ino,
 908					      total_reserved_size, 0);
 909		btrfs_block_rsv_release(fs_info, &fs_info->delayed_block_rsv,
 910					total_reserved_size, NULL);
 911	}
 912
 913	list_for_each_entry_safe(curr, next, &batch_list, tree_list) {
 
 914		list_del(&curr->tree_list);
 915		btrfs_release_delayed_item(curr);
 916	}
 917
 918	return 0;
 
 919}
 920
 921static int btrfs_delete_delayed_items(struct btrfs_trans_handle *trans,
 922				      struct btrfs_path *path,
 923				      struct btrfs_root *root,
 924				      struct btrfs_delayed_node *node)
 925{
 926	struct btrfs_key key;
 927	int ret = 0;
 928
 929	key.objectid = node->inode_id;
 930	key.type = BTRFS_DIR_INDEX_KEY;
 931
 932	while (ret == 0) {
 933		struct btrfs_delayed_item *item;
 934
 935		mutex_lock(&node->mutex);
 936		item = __btrfs_first_delayed_deletion_item(node);
 937		if (!item) {
 938			mutex_unlock(&node->mutex);
 939			break;
 940		}
 941
 942		key.offset = item->index;
 943		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 944		if (ret > 0) {
 945			/*
 946			 * There's no matching item in the leaf. This means we
 947			 * have already deleted this item in a past run of the
 948			 * delayed items. We ignore errors when running delayed
 949			 * items from an async context, through a work queue job
 950			 * running btrfs_async_run_delayed_root(), and don't
 951			 * release delayed items that failed to complete. This
 952			 * is because we will retry later, and at transaction
 953			 * commit time we always run delayed items and will
 954			 * then deal with errors if they fail to run again.
 955			 *
 956			 * So just release delayed items for which we can't find
 957			 * an item in the tree, and move to the next item.
 958			 */
 959			btrfs_release_path(path);
 960			btrfs_release_delayed_item(item);
 961			ret = 0;
 962		} else if (ret == 0) {
 963			ret = btrfs_batch_delete_items(trans, root, path, item);
 964			btrfs_release_path(path);
 965		}
 966
 
 
 
 
 967		/*
 968		 * We unlock and relock on each iteration, this is to prevent
 969		 * blocking other tasks for too long while we are being run from
 970		 * the async context (work queue job). Those tasks are typically
 971		 * running system calls like creat/mkdir/rename/unlink/etc which
 972		 * need to add delayed items to this delayed node.
 973		 */
 974		mutex_unlock(&node->mutex);
 
 
 
 
 
 
 
 
 
 975	}
 976
 
 
 
 
 
 
 
 
 977	return ret;
 978}
 979
 980static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node)
 981{
 982	struct btrfs_delayed_root *delayed_root;
 983
 984	if (delayed_node &&
 985	    test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
 986		ASSERT(delayed_node->root);
 987		clear_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
 988		delayed_node->count--;
 989
 990		delayed_root = delayed_node->root->fs_info->delayed_root;
 991		finish_one_item(delayed_root);
 992	}
 993}
 994
 995static void btrfs_release_delayed_iref(struct btrfs_delayed_node *delayed_node)
 996{
 
 997
 998	if (test_and_clear_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags)) {
 999		struct btrfs_delayed_root *delayed_root;
 
1000
1001		ASSERT(delayed_node->root);
1002		delayed_node->count--;
1003
1004		delayed_root = delayed_node->root->fs_info->delayed_root;
1005		finish_one_item(delayed_root);
1006	}
1007}
1008
1009static int __btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1010					struct btrfs_root *root,
1011					struct btrfs_path *path,
1012					struct btrfs_delayed_node *node)
1013{
1014	struct btrfs_fs_info *fs_info = root->fs_info;
1015	struct btrfs_key key;
1016	struct btrfs_inode_item *inode_item;
1017	struct extent_buffer *leaf;
1018	int mod;
1019	int ret;
1020
1021	key.objectid = node->inode_id;
1022	key.type = BTRFS_INODE_ITEM_KEY;
1023	key.offset = 0;
1024
1025	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1026		mod = -1;
1027	else
1028		mod = 1;
1029
1030	ret = btrfs_lookup_inode(trans, root, path, &key, mod);
1031	if (ret > 0)
1032		ret = -ENOENT;
1033	if (ret < 0)
1034		goto out;
 
 
1035
1036	leaf = path->nodes[0];
1037	inode_item = btrfs_item_ptr(leaf, path->slots[0],
1038				    struct btrfs_inode_item);
1039	write_extent_buffer(leaf, &node->inode_item, (unsigned long)inode_item,
1040			    sizeof(struct btrfs_inode_item));
1041	btrfs_mark_buffer_dirty(trans, leaf);
1042
1043	if (!test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &node->flags))
1044		goto out;
1045
1046	/*
1047	 * Now we're going to delete the INODE_REF/EXTREF, which should be the
1048	 * only one ref left.  Check if the next item is an INODE_REF/EXTREF.
1049	 *
1050	 * But if we're the last item already, release and search for the last
1051	 * INODE_REF/EXTREF.
1052	 */
1053	if (path->slots[0] + 1 >= btrfs_header_nritems(leaf)) {
1054		key.objectid = node->inode_id;
1055		key.type = BTRFS_INODE_EXTREF_KEY;
1056		key.offset = (u64)-1;
1057
1058		btrfs_release_path(path);
1059		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1060		if (ret < 0)
1061			goto err_out;
1062		ASSERT(ret > 0);
1063		ASSERT(path->slots[0] > 0);
1064		ret = 0;
1065		path->slots[0]--;
1066		leaf = path->nodes[0];
1067	} else {
1068		path->slots[0]++;
1069	}
1070	btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1071	if (key.objectid != node->inode_id)
1072		goto out;
 
1073	if (key.type != BTRFS_INODE_REF_KEY &&
1074	    key.type != BTRFS_INODE_EXTREF_KEY)
1075		goto out;
1076
1077	/*
1078	 * Delayed iref deletion is for the inode who has only one link,
1079	 * so there is only one iref. The case that several irefs are
1080	 * in the same item doesn't exist.
1081	 */
1082	ret = btrfs_del_item(trans, root, path);
1083out:
1084	btrfs_release_delayed_iref(node);
 
1085	btrfs_release_path(path);
1086err_out:
1087	btrfs_delayed_inode_release_metadata(fs_info, node, (ret < 0));
1088	btrfs_release_delayed_inode(node);
1089
1090	/*
1091	 * If we fail to update the delayed inode we need to abort the
1092	 * transaction, because we could leave the inode with the improper
1093	 * counts behind.
1094	 */
1095	if (ret && ret != -ENOENT)
1096		btrfs_abort_transaction(trans, ret);
 
 
 
 
1097
1098	return ret;
 
 
 
1099}
1100
1101static inline int btrfs_update_delayed_inode(struct btrfs_trans_handle *trans,
1102					     struct btrfs_root *root,
1103					     struct btrfs_path *path,
1104					     struct btrfs_delayed_node *node)
1105{
1106	int ret;
1107
1108	mutex_lock(&node->mutex);
1109	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &node->flags)) {
1110		mutex_unlock(&node->mutex);
1111		return 0;
1112	}
1113
1114	ret = __btrfs_update_delayed_inode(trans, root, path, node);
1115	mutex_unlock(&node->mutex);
1116	return ret;
1117}
1118
1119static inline int
1120__btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1121				   struct btrfs_path *path,
1122				   struct btrfs_delayed_node *node)
1123{
1124	int ret;
1125
1126	ret = btrfs_insert_delayed_items(trans, path, node->root, node);
1127	if (ret)
1128		return ret;
1129
1130	ret = btrfs_delete_delayed_items(trans, path, node->root, node);
1131	if (ret)
1132		return ret;
1133
1134	ret = btrfs_record_root_in_trans(trans, node->root);
1135	if (ret)
1136		return ret;
1137	ret = btrfs_update_delayed_inode(trans, node->root, path, node);
1138	return ret;
1139}
1140
1141/*
1142 * Called when committing the transaction.
1143 * Returns 0 on success.
1144 * Returns < 0 on error and returns with an aborted transaction with any
1145 * outstanding delayed items cleaned up.
1146 */
1147static int __btrfs_run_delayed_items(struct btrfs_trans_handle *trans, int nr)
 
1148{
1149	struct btrfs_fs_info *fs_info = trans->fs_info;
1150	struct btrfs_delayed_root *delayed_root;
1151	struct btrfs_delayed_node *curr_node, *prev_node;
1152	struct btrfs_path *path;
1153	struct btrfs_block_rsv *block_rsv;
1154	int ret = 0;
1155	bool count = (nr > 0);
1156
1157	if (TRANS_ABORTED(trans))
1158		return -EIO;
1159
1160	path = btrfs_alloc_path();
1161	if (!path)
1162		return -ENOMEM;
 
1163
1164	block_rsv = trans->block_rsv;
1165	trans->block_rsv = &fs_info->delayed_block_rsv;
1166
1167	delayed_root = fs_info->delayed_root;
1168
1169	curr_node = btrfs_first_delayed_node(delayed_root);
1170	while (curr_node && (!count || nr--)) {
1171		ret = __btrfs_commit_inode_delayed_items(trans, path,
1172							 curr_node);
1173		if (ret) {
 
 
1174			btrfs_abort_transaction(trans, ret);
1175			break;
1176		}
1177
1178		prev_node = curr_node;
1179		curr_node = btrfs_next_delayed_node(curr_node);
1180		/*
1181		 * See the comment below about releasing path before releasing
1182		 * node. If the commit of delayed items was successful the path
1183		 * should always be released, but in case of an error, it may
1184		 * point to locked extent buffers (a leaf at the very least).
1185		 */
1186		ASSERT(path->nodes[0] == NULL);
1187		btrfs_release_delayed_node(prev_node);
1188	}
1189
1190	/*
1191	 * Release the path to avoid a potential deadlock and lockdep splat when
1192	 * releasing the delayed node, as that requires taking the delayed node's
1193	 * mutex. If another task starts running delayed items before we take
1194	 * the mutex, it will first lock the mutex and then it may try to lock
1195	 * the same btree path (leaf).
1196	 */
1197	btrfs_free_path(path);
1198
1199	if (curr_node)
1200		btrfs_release_delayed_node(curr_node);
 
1201	trans->block_rsv = block_rsv;
1202
1203	return ret;
1204}
1205
1206int btrfs_run_delayed_items(struct btrfs_trans_handle *trans)
 
1207{
1208	return __btrfs_run_delayed_items(trans, -1);
1209}
1210
1211int btrfs_run_delayed_items_nr(struct btrfs_trans_handle *trans, int nr)
 
1212{
1213	return __btrfs_run_delayed_items(trans, nr);
1214}
1215
1216int btrfs_commit_inode_delayed_items(struct btrfs_trans_handle *trans,
1217				     struct btrfs_inode *inode)
1218{
1219	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1220	struct btrfs_path *path;
1221	struct btrfs_block_rsv *block_rsv;
1222	int ret;
1223
1224	if (!delayed_node)
1225		return 0;
1226
1227	mutex_lock(&delayed_node->mutex);
1228	if (!delayed_node->count) {
1229		mutex_unlock(&delayed_node->mutex);
1230		btrfs_release_delayed_node(delayed_node);
1231		return 0;
1232	}
1233	mutex_unlock(&delayed_node->mutex);
1234
1235	path = btrfs_alloc_path();
1236	if (!path) {
1237		btrfs_release_delayed_node(delayed_node);
1238		return -ENOMEM;
1239	}
 
1240
1241	block_rsv = trans->block_rsv;
1242	trans->block_rsv = &delayed_node->root->fs_info->delayed_block_rsv;
1243
1244	ret = __btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1245
1246	btrfs_release_delayed_node(delayed_node);
1247	btrfs_free_path(path);
1248	trans->block_rsv = block_rsv;
1249
1250	return ret;
1251}
1252
1253int btrfs_commit_inode_delayed_inode(struct btrfs_inode *inode)
1254{
1255	struct btrfs_fs_info *fs_info = inode->root->fs_info;
1256	struct btrfs_trans_handle *trans;
1257	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1258	struct btrfs_path *path;
1259	struct btrfs_block_rsv *block_rsv;
1260	int ret;
1261
1262	if (!delayed_node)
1263		return 0;
1264
1265	mutex_lock(&delayed_node->mutex);
1266	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1267		mutex_unlock(&delayed_node->mutex);
1268		btrfs_release_delayed_node(delayed_node);
1269		return 0;
1270	}
1271	mutex_unlock(&delayed_node->mutex);
1272
1273	trans = btrfs_join_transaction(delayed_node->root);
1274	if (IS_ERR(trans)) {
1275		ret = PTR_ERR(trans);
1276		goto out;
1277	}
1278
1279	path = btrfs_alloc_path();
1280	if (!path) {
1281		ret = -ENOMEM;
1282		goto trans_out;
1283	}
 
1284
1285	block_rsv = trans->block_rsv;
1286	trans->block_rsv = &fs_info->delayed_block_rsv;
1287
1288	mutex_lock(&delayed_node->mutex);
1289	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags))
1290		ret = __btrfs_update_delayed_inode(trans, delayed_node->root,
1291						   path, delayed_node);
1292	else
1293		ret = 0;
1294	mutex_unlock(&delayed_node->mutex);
1295
1296	btrfs_free_path(path);
1297	trans->block_rsv = block_rsv;
1298trans_out:
1299	btrfs_end_transaction(trans);
1300	btrfs_btree_balance_dirty(fs_info);
1301out:
1302	btrfs_release_delayed_node(delayed_node);
1303
1304	return ret;
1305}
1306
1307void btrfs_remove_delayed_node(struct btrfs_inode *inode)
1308{
1309	struct btrfs_delayed_node *delayed_node;
1310
1311	delayed_node = READ_ONCE(inode->delayed_node);
1312	if (!delayed_node)
1313		return;
1314
1315	inode->delayed_node = NULL;
1316	btrfs_release_delayed_node(delayed_node);
1317}
1318
1319struct btrfs_async_delayed_work {
1320	struct btrfs_delayed_root *delayed_root;
1321	int nr;
1322	struct btrfs_work work;
1323};
1324
1325static void btrfs_async_run_delayed_root(struct btrfs_work *work)
1326{
1327	struct btrfs_async_delayed_work *async_work;
1328	struct btrfs_delayed_root *delayed_root;
1329	struct btrfs_trans_handle *trans;
1330	struct btrfs_path *path;
1331	struct btrfs_delayed_node *delayed_node = NULL;
1332	struct btrfs_root *root;
1333	struct btrfs_block_rsv *block_rsv;
1334	int total_done = 0;
1335
1336	async_work = container_of(work, struct btrfs_async_delayed_work, work);
1337	delayed_root = async_work->delayed_root;
1338
1339	path = btrfs_alloc_path();
1340	if (!path)
1341		goto out;
1342
1343	do {
1344		if (atomic_read(&delayed_root->items) <
1345		    BTRFS_DELAYED_BACKGROUND / 2)
1346			break;
1347
1348		delayed_node = btrfs_first_prepared_delayed_node(delayed_root);
1349		if (!delayed_node)
1350			break;
1351
1352		root = delayed_node->root;
 
1353
1354		trans = btrfs_join_transaction(root);
1355		if (IS_ERR(trans)) {
1356			btrfs_release_path(path);
1357			btrfs_release_prepared_delayed_node(delayed_node);
1358			total_done++;
1359			continue;
1360		}
1361
1362		block_rsv = trans->block_rsv;
1363		trans->block_rsv = &root->fs_info->delayed_block_rsv;
1364
1365		__btrfs_commit_inode_delayed_items(trans, path, delayed_node);
1366
1367		trans->block_rsv = block_rsv;
1368		btrfs_end_transaction(trans);
1369		btrfs_btree_balance_dirty_nodelay(root->fs_info);
1370
1371		btrfs_release_path(path);
1372		btrfs_release_prepared_delayed_node(delayed_node);
1373		total_done++;
1374
1375	} while ((async_work->nr == 0 && total_done < BTRFS_DELAYED_WRITEBACK)
1376		 || total_done < async_work->nr);
 
 
1377
 
1378	btrfs_free_path(path);
1379out:
1380	wake_up(&delayed_root->wait);
1381	kfree(async_work);
1382}
1383
1384
1385static int btrfs_wq_run_delayed_node(struct btrfs_delayed_root *delayed_root,
1386				     struct btrfs_fs_info *fs_info, int nr)
1387{
1388	struct btrfs_async_delayed_work *async_work;
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, NULL);
 
1396	async_work->nr = nr;
1397
1398	btrfs_queue_work(fs_info->delayed_workers, &async_work->work);
1399	return 0;
1400}
1401
1402void btrfs_assert_delayed_root_empty(struct btrfs_fs_info *fs_info)
1403{
1404	WARN_ON(btrfs_first_delayed_node(fs_info->delayed_root));
1405}
1406
1407static int could_end_wait(struct btrfs_delayed_root *delayed_root, int seq)
1408{
1409	int val = atomic_read(&delayed_root->items_seq);
1410
1411	if (val < seq || val >= seq + BTRFS_DELAYED_BATCH)
1412		return 1;
1413
1414	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND)
1415		return 1;
1416
1417	return 0;
1418}
1419
1420void btrfs_balance_delayed_items(struct btrfs_fs_info *fs_info)
1421{
1422	struct btrfs_delayed_root *delayed_root = fs_info->delayed_root;
1423
1424	if ((atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND) ||
1425		btrfs_workqueue_normal_congested(fs_info->delayed_workers))
1426		return;
1427
1428	if (atomic_read(&delayed_root->items) >= BTRFS_DELAYED_WRITEBACK) {
1429		int seq;
1430		int ret;
1431
1432		seq = atomic_read(&delayed_root->items_seq);
1433
1434		ret = btrfs_wq_run_delayed_node(delayed_root, fs_info, 0);
1435		if (ret)
1436			return;
1437
1438		wait_event_interruptible(delayed_root->wait,
1439					 could_end_wait(delayed_root, seq));
1440		return;
1441	}
1442
1443	btrfs_wq_run_delayed_node(delayed_root, fs_info, BTRFS_DELAYED_BATCH);
1444}
1445
1446static void btrfs_release_dir_index_item_space(struct btrfs_trans_handle *trans)
1447{
1448	struct btrfs_fs_info *fs_info = trans->fs_info;
1449	const u64 bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
1450
1451	if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
1452		return;
1453
1454	/*
1455	 * Adding the new dir index item does not require touching another
1456	 * leaf, so we can release 1 unit of metadata that was previously
1457	 * reserved when starting the transaction. This applies only to
1458	 * the case where we had a transaction start and excludes the
1459	 * transaction join case (when replaying log trees).
1460	 */
1461	trace_btrfs_space_reservation(fs_info, "transaction",
1462				      trans->transid, bytes, 0);
1463	btrfs_block_rsv_release(fs_info, trans->block_rsv, bytes, NULL);
1464	ASSERT(trans->bytes_reserved >= bytes);
1465	trans->bytes_reserved -= bytes;
1466}
1467
1468/* Will return 0, -ENOMEM or -EEXIST (index number collision, unexpected). */
1469int btrfs_insert_delayed_dir_index(struct btrfs_trans_handle *trans,
 
1470				   const char *name, int name_len,
1471				   struct btrfs_inode *dir,
1472				   const struct btrfs_disk_key *disk_key, u8 flags,
1473				   u64 index)
1474{
1475	struct btrfs_fs_info *fs_info = trans->fs_info;
1476	const unsigned int leaf_data_size = BTRFS_LEAF_DATA_SIZE(fs_info);
1477	struct btrfs_delayed_node *delayed_node;
1478	struct btrfs_delayed_item *delayed_item;
1479	struct btrfs_dir_item *dir_item;
1480	bool reserve_leaf_space;
1481	u32 data_len;
1482	int ret;
1483
1484	delayed_node = btrfs_get_or_create_delayed_node(dir);
1485	if (IS_ERR(delayed_node))
1486		return PTR_ERR(delayed_node);
1487
1488	delayed_item = btrfs_alloc_delayed_item(sizeof(*dir_item) + name_len,
1489						delayed_node,
1490						BTRFS_DELAYED_INSERTION_ITEM);
1491	if (!delayed_item) {
1492		ret = -ENOMEM;
1493		goto release_node;
1494	}
1495
1496	delayed_item->index = index;
 
 
1497
1498	dir_item = (struct btrfs_dir_item *)delayed_item->data;
1499	dir_item->location = *disk_key;
1500	btrfs_set_stack_dir_transid(dir_item, trans->transid);
1501	btrfs_set_stack_dir_data_len(dir_item, 0);
1502	btrfs_set_stack_dir_name_len(dir_item, name_len);
1503	btrfs_set_stack_dir_flags(dir_item, flags);
1504	memcpy((char *)(dir_item + 1), name, name_len);
1505
1506	data_len = delayed_item->data_len + sizeof(struct btrfs_item);
1507
1508	mutex_lock(&delayed_node->mutex);
1509
1510	/*
1511	 * First attempt to insert the delayed item. This is to make the error
1512	 * handling path simpler in case we fail (-EEXIST). There's no risk of
1513	 * any other task coming in and running the delayed item before we do
1514	 * the metadata space reservation below, because we are holding the
1515	 * delayed node's mutex and that mutex must also be locked before the
1516	 * node's delayed items can be run.
1517	 */
1518	ret = __btrfs_add_delayed_item(delayed_node, delayed_item);
1519	if (unlikely(ret)) {
1520		btrfs_err(trans->fs_info,
1521"error adding delayed dir index item, name: %.*s, index: %llu, root: %llu, dir: %llu, dir->index_cnt: %llu, delayed_node->index_cnt: %llu, error: %d",
1522			  name_len, name, index, btrfs_root_id(delayed_node->root),
1523			  delayed_node->inode_id, dir->index_cnt,
1524			  delayed_node->index_cnt, ret);
1525		btrfs_release_delayed_item(delayed_item);
1526		btrfs_release_dir_index_item_space(trans);
1527		mutex_unlock(&delayed_node->mutex);
1528		goto release_node;
1529	}
1530
1531	if (delayed_node->index_item_leaves == 0 ||
1532	    delayed_node->curr_index_batch_size + data_len > leaf_data_size) {
1533		delayed_node->curr_index_batch_size = data_len;
1534		reserve_leaf_space = true;
1535	} else {
1536		delayed_node->curr_index_batch_size += data_len;
1537		reserve_leaf_space = false;
1538	}
1539
1540	if (reserve_leaf_space) {
1541		ret = btrfs_delayed_item_reserve_metadata(trans, delayed_item);
1542		/*
1543		 * Space was reserved for a dir index item insertion when we
1544		 * started the transaction, so getting a failure here should be
1545		 * impossible.
1546		 */
1547		if (WARN_ON(ret)) {
1548			btrfs_release_delayed_item(delayed_item);
1549			mutex_unlock(&delayed_node->mutex);
1550			goto release_node;
1551		}
1552
1553		delayed_node->index_item_leaves++;
1554	} else {
1555		btrfs_release_dir_index_item_space(trans);
 
 
 
 
 
1556	}
1557	mutex_unlock(&delayed_node->mutex);
1558
1559release_node:
1560	btrfs_release_delayed_node(delayed_node);
1561	return ret;
1562}
1563
1564static int btrfs_delete_delayed_insertion_item(struct btrfs_fs_info *fs_info,
1565					       struct btrfs_delayed_node *node,
1566					       u64 index)
1567{
1568	struct btrfs_delayed_item *item;
1569
1570	mutex_lock(&node->mutex);
1571	item = __btrfs_lookup_delayed_item(&node->ins_root.rb_root, index);
1572	if (!item) {
1573		mutex_unlock(&node->mutex);
1574		return 1;
1575	}
1576
1577	/*
1578	 * For delayed items to insert, we track reserved metadata bytes based
1579	 * on the number of leaves that we will use.
1580	 * See btrfs_insert_delayed_dir_index() and
1581	 * btrfs_delayed_item_reserve_metadata()).
1582	 */
1583	ASSERT(item->bytes_reserved == 0);
1584	ASSERT(node->index_item_leaves > 0);
1585
1586	/*
1587	 * If there's only one leaf reserved, we can decrement this item from the
1588	 * current batch, otherwise we can not because we don't know which leaf
1589	 * it belongs to. With the current limit on delayed items, we rarely
1590	 * accumulate enough dir index items to fill more than one leaf (even
1591	 * when using a leaf size of 4K).
1592	 */
1593	if (node->index_item_leaves == 1) {
1594		const u32 data_len = item->data_len + sizeof(struct btrfs_item);
1595
1596		ASSERT(node->curr_index_batch_size >= data_len);
1597		node->curr_index_batch_size -= data_len;
1598	}
1599
1600	btrfs_release_delayed_item(item);
1601
1602	/* If we now have no more dir index items, we can release all leaves. */
1603	if (RB_EMPTY_ROOT(&node->ins_root.rb_root)) {
1604		btrfs_delayed_item_release_leaves(node, node->index_item_leaves);
1605		node->index_item_leaves = 0;
1606	}
1607
1608	mutex_unlock(&node->mutex);
1609	return 0;
1610}
1611
1612int btrfs_delete_delayed_dir_index(struct btrfs_trans_handle *trans,
1613				   struct btrfs_inode *dir, u64 index)
 
1614{
1615	struct btrfs_delayed_node *node;
1616	struct btrfs_delayed_item *item;
 
1617	int ret;
1618
1619	node = btrfs_get_or_create_delayed_node(dir);
1620	if (IS_ERR(node))
1621		return PTR_ERR(node);
1622
1623	ret = btrfs_delete_delayed_insertion_item(trans->fs_info, node, index);
 
 
 
 
1624	if (!ret)
1625		goto end;
1626
1627	item = btrfs_alloc_delayed_item(0, node, BTRFS_DELAYED_DELETION_ITEM);
1628	if (!item) {
1629		ret = -ENOMEM;
1630		goto end;
1631	}
1632
1633	item->index = index;
1634
1635	ret = btrfs_delayed_item_reserve_metadata(trans, item);
1636	/*
1637	 * we have reserved enough space when we start a new transaction,
1638	 * so reserving metadata failure is impossible.
1639	 */
1640	if (ret < 0) {
1641		btrfs_err(trans->fs_info,
1642"metadata reservation failed for delayed dir item deltiona, should have been reserved");
1643		btrfs_release_delayed_item(item);
1644		goto end;
1645	}
1646
1647	mutex_lock(&node->mutex);
1648	ret = __btrfs_add_delayed_item(node, item);
1649	if (unlikely(ret)) {
1650		btrfs_err(trans->fs_info,
1651			  "err add delayed dir index item(index: %llu) into the deletion tree of the delayed node(root id: %llu, inode id: %llu, errno: %d)",
1652			  index, btrfs_root_id(node->root),
1653			  node->inode_id, ret);
1654		btrfs_delayed_item_release_metadata(dir->root, item);
1655		btrfs_release_delayed_item(item);
1656	}
1657	mutex_unlock(&node->mutex);
1658end:
1659	btrfs_release_delayed_node(node);
1660	return ret;
1661}
1662
1663int btrfs_inode_delayed_dir_index_count(struct btrfs_inode *inode)
1664{
1665	struct btrfs_delayed_node *delayed_node = btrfs_get_delayed_node(inode);
1666
1667	if (!delayed_node)
1668		return -ENOENT;
1669
1670	/*
1671	 * Since we have held i_mutex of this directory, it is impossible that
1672	 * a new directory index is added into the delayed node and index_cnt
1673	 * is updated now. So we needn't lock the delayed node.
1674	 */
1675	if (!delayed_node->index_cnt) {
1676		btrfs_release_delayed_node(delayed_node);
1677		return -EINVAL;
1678	}
1679
1680	inode->index_cnt = delayed_node->index_cnt;
1681	btrfs_release_delayed_node(delayed_node);
1682	return 0;
1683}
1684
1685bool btrfs_readdir_get_delayed_items(struct btrfs_inode *inode,
1686				     u64 last_index,
1687				     struct list_head *ins_list,
1688				     struct list_head *del_list)
1689{
1690	struct btrfs_delayed_node *delayed_node;
1691	struct btrfs_delayed_item *item;
1692
1693	delayed_node = btrfs_get_delayed_node(inode);
1694	if (!delayed_node)
1695		return false;
1696
1697	/*
1698	 * We can only do one readdir with delayed items at a time because of
1699	 * item->readdir_list.
1700	 */
1701	btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED);
1702	btrfs_inode_lock(inode, 0);
1703
1704	mutex_lock(&delayed_node->mutex);
1705	item = __btrfs_first_delayed_insertion_item(delayed_node);
1706	while (item && item->index <= last_index) {
1707		refcount_inc(&item->refs);
1708		list_add_tail(&item->readdir_list, ins_list);
1709		item = __btrfs_next_delayed_item(item);
1710	}
1711
1712	item = __btrfs_first_delayed_deletion_item(delayed_node);
1713	while (item && item->index <= last_index) {
1714		refcount_inc(&item->refs);
1715		list_add_tail(&item->readdir_list, del_list);
1716		item = __btrfs_next_delayed_item(item);
1717	}
1718	mutex_unlock(&delayed_node->mutex);
1719	/*
1720	 * This delayed node is still cached in the btrfs inode, so refs
1721	 * must be > 1 now, and we needn't check it is going to be freed
1722	 * or not.
1723	 *
1724	 * Besides that, this function is used to read dir, we do not
1725	 * insert/delete delayed items in this period. So we also needn't
1726	 * requeue or dequeue this delayed node.
1727	 */
1728	refcount_dec(&delayed_node->refs);
1729
1730	return true;
1731}
1732
1733void btrfs_readdir_put_delayed_items(struct btrfs_inode *inode,
1734				     struct list_head *ins_list,
1735				     struct list_head *del_list)
1736{
1737	struct btrfs_delayed_item *curr, *next;
1738
1739	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1740		list_del(&curr->readdir_list);
1741		if (refcount_dec_and_test(&curr->refs))
1742			kfree(curr);
1743	}
1744
1745	list_for_each_entry_safe(curr, next, del_list, readdir_list) {
1746		list_del(&curr->readdir_list);
1747		if (refcount_dec_and_test(&curr->refs))
1748			kfree(curr);
1749	}
1750
1751	/*
1752	 * The VFS is going to do up_read(), so we need to downgrade back to a
1753	 * read lock.
1754	 */
1755	downgrade_write(&inode->vfs_inode.i_rwsem);
1756}
1757
1758int btrfs_should_delete_dir_index(const struct list_head *del_list,
1759				  u64 index)
1760{
1761	struct btrfs_delayed_item *curr;
1762	int ret = 0;
 
 
 
1763
1764	list_for_each_entry(curr, del_list, readdir_list) {
1765		if (curr->index > index)
1766			break;
1767		if (curr->index == index) {
1768			ret = 1;
1769			break;
1770		}
 
 
 
 
 
 
 
1771	}
1772	return ret;
1773}
1774
1775/*
1776 * Read dir info stored in the delayed tree.
 
1777 */
1778int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
1779				    const struct list_head *ins_list)
1780{
1781	struct btrfs_dir_item *di;
1782	struct btrfs_delayed_item *curr, *next;
1783	struct btrfs_key location;
1784	char *name;
1785	int name_len;
1786	int over = 0;
1787	unsigned char d_type;
1788
 
 
 
1789	/*
1790	 * Changing the data of the delayed item is impossible. So
1791	 * we needn't lock them. And we have held i_mutex of the
1792	 * directory, nobody can delete any directory indexes now.
1793	 */
1794	list_for_each_entry_safe(curr, next, ins_list, readdir_list) {
1795		list_del(&curr->readdir_list);
1796
1797		if (curr->index < ctx->pos) {
1798			if (refcount_dec_and_test(&curr->refs))
1799				kfree(curr);
1800			continue;
1801		}
1802
1803		ctx->pos = curr->index;
1804
1805		di = (struct btrfs_dir_item *)curr->data;
1806		name = (char *)(di + 1);
1807		name_len = btrfs_stack_dir_name_len(di);
1808
1809		d_type = fs_ftype_to_dtype(btrfs_dir_flags_to_ftype(di->type));
1810		btrfs_disk_key_to_cpu(&location, &di->location);
1811
1812		over = !dir_emit(ctx, name, name_len,
1813			       location.objectid, d_type);
1814
1815		if (refcount_dec_and_test(&curr->refs))
1816			kfree(curr);
1817
1818		if (over)
1819			return 1;
1820		ctx->pos++;
1821	}
1822	return 0;
1823}
1824
1825static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
1826				  struct btrfs_inode_item *inode_item,
1827				  struct inode *inode)
1828{
1829	u64 flags;
1830
1831	btrfs_set_stack_inode_uid(inode_item, i_uid_read(inode));
1832	btrfs_set_stack_inode_gid(inode_item, i_gid_read(inode));
1833	btrfs_set_stack_inode_size(inode_item, BTRFS_I(inode)->disk_i_size);
1834	btrfs_set_stack_inode_mode(inode_item, inode->i_mode);
1835	btrfs_set_stack_inode_nlink(inode_item, inode->i_nlink);
1836	btrfs_set_stack_inode_nbytes(inode_item, inode_get_bytes(inode));
1837	btrfs_set_stack_inode_generation(inode_item,
1838					 BTRFS_I(inode)->generation);
1839	btrfs_set_stack_inode_sequence(inode_item,
1840				       inode_peek_iversion(inode));
1841	btrfs_set_stack_inode_transid(inode_item, trans->transid);
1842	btrfs_set_stack_inode_rdev(inode_item, inode->i_rdev);
1843	flags = btrfs_inode_combine_flags(BTRFS_I(inode)->flags,
1844					  BTRFS_I(inode)->ro_flags);
1845	btrfs_set_stack_inode_flags(inode_item, flags);
1846	btrfs_set_stack_inode_block_group(inode_item, 0);
1847
1848	btrfs_set_stack_timespec_sec(&inode_item->atime,
1849				     inode_get_atime_sec(inode));
1850	btrfs_set_stack_timespec_nsec(&inode_item->atime,
1851				      inode_get_atime_nsec(inode));
1852
1853	btrfs_set_stack_timespec_sec(&inode_item->mtime,
1854				     inode_get_mtime_sec(inode));
1855	btrfs_set_stack_timespec_nsec(&inode_item->mtime,
1856				      inode_get_mtime_nsec(inode));
1857
1858	btrfs_set_stack_timespec_sec(&inode_item->ctime,
1859				     inode_get_ctime_sec(inode));
1860	btrfs_set_stack_timespec_nsec(&inode_item->ctime,
1861				      inode_get_ctime_nsec(inode));
1862
1863	btrfs_set_stack_timespec_sec(&inode_item->otime, BTRFS_I(inode)->i_otime_sec);
1864	btrfs_set_stack_timespec_nsec(&inode_item->otime, BTRFS_I(inode)->i_otime_nsec);
 
 
1865}
1866
1867int btrfs_fill_inode(struct inode *inode, u32 *rdev)
1868{
1869	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1870	struct btrfs_delayed_node *delayed_node;
1871	struct btrfs_inode_item *inode_item;
1872
1873	delayed_node = btrfs_get_delayed_node(BTRFS_I(inode));
1874	if (!delayed_node)
1875		return -ENOENT;
1876
1877	mutex_lock(&delayed_node->mutex);
1878	if (!test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1879		mutex_unlock(&delayed_node->mutex);
1880		btrfs_release_delayed_node(delayed_node);
1881		return -ENOENT;
1882	}
1883
1884	inode_item = &delayed_node->inode_item;
1885
1886	i_uid_write(inode, btrfs_stack_inode_uid(inode_item));
1887	i_gid_write(inode, btrfs_stack_inode_gid(inode_item));
1888	btrfs_i_size_write(BTRFS_I(inode), btrfs_stack_inode_size(inode_item));
1889	btrfs_inode_set_file_extent_range(BTRFS_I(inode), 0,
1890			round_up(i_size_read(inode), fs_info->sectorsize));
1891	inode->i_mode = btrfs_stack_inode_mode(inode_item);
1892	set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
1893	inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
1894	BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
1895        BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
1896
1897	inode_set_iversion_queried(inode,
1898				   btrfs_stack_inode_sequence(inode_item));
1899	inode->i_rdev = 0;
1900	*rdev = btrfs_stack_inode_rdev(inode_item);
1901	btrfs_inode_split_flags(btrfs_stack_inode_flags(inode_item),
1902				&BTRFS_I(inode)->flags, &BTRFS_I(inode)->ro_flags);
1903
1904	inode_set_atime(inode, btrfs_stack_timespec_sec(&inode_item->atime),
1905			btrfs_stack_timespec_nsec(&inode_item->atime));
1906
1907	inode_set_mtime(inode, btrfs_stack_timespec_sec(&inode_item->mtime),
1908			btrfs_stack_timespec_nsec(&inode_item->mtime));
1909
1910	inode_set_ctime(inode, btrfs_stack_timespec_sec(&inode_item->ctime),
1911			btrfs_stack_timespec_nsec(&inode_item->ctime));
1912
1913	BTRFS_I(inode)->i_otime_sec = btrfs_stack_timespec_sec(&inode_item->otime);
1914	BTRFS_I(inode)->i_otime_nsec = btrfs_stack_timespec_nsec(&inode_item->otime);
 
 
1915
1916	inode->i_generation = BTRFS_I(inode)->generation;
1917	if (S_ISDIR(inode->i_mode))
1918		BTRFS_I(inode)->index_cnt = (u64)-1;
1919
1920	mutex_unlock(&delayed_node->mutex);
1921	btrfs_release_delayed_node(delayed_node);
1922	return 0;
1923}
1924
1925int btrfs_delayed_update_inode(struct btrfs_trans_handle *trans,
1926			       struct btrfs_inode *inode)
1927{
1928	struct btrfs_root *root = inode->root;
1929	struct btrfs_delayed_node *delayed_node;
1930	int ret = 0;
1931
1932	delayed_node = btrfs_get_or_create_delayed_node(inode);
1933	if (IS_ERR(delayed_node))
1934		return PTR_ERR(delayed_node);
1935
1936	mutex_lock(&delayed_node->mutex);
1937	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
1938		fill_stack_inode_item(trans, &delayed_node->inode_item,
1939				      &inode->vfs_inode);
1940		goto release_node;
1941	}
1942
1943	ret = btrfs_delayed_inode_reserve_metadata(trans, root, delayed_node);
 
1944	if (ret)
1945		goto release_node;
1946
1947	fill_stack_inode_item(trans, &delayed_node->inode_item, &inode->vfs_inode);
1948	set_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags);
1949	delayed_node->count++;
1950	atomic_inc(&root->fs_info->delayed_root->items);
1951release_node:
1952	mutex_unlock(&delayed_node->mutex);
1953	btrfs_release_delayed_node(delayed_node);
1954	return ret;
1955}
1956
1957int btrfs_delayed_delete_inode_ref(struct btrfs_inode *inode)
1958{
1959	struct btrfs_fs_info *fs_info = inode->root->fs_info;
1960	struct btrfs_delayed_node *delayed_node;
1961
1962	/*
1963	 * we don't do delayed inode updates during log recovery because it
1964	 * leads to enospc problems.  This means we also can't do
1965	 * delayed inode refs
1966	 */
1967	if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
1968		return -EAGAIN;
1969
1970	delayed_node = btrfs_get_or_create_delayed_node(inode);
1971	if (IS_ERR(delayed_node))
1972		return PTR_ERR(delayed_node);
1973
1974	/*
1975	 * We don't reserve space for inode ref deletion is because:
1976	 * - We ONLY do async inode ref deletion for the inode who has only
1977	 *   one link(i_nlink == 1), it means there is only one inode ref.
1978	 *   And in most case, the inode ref and the inode item are in the
1979	 *   same leaf, and we will deal with them at the same time.
1980	 *   Since we are sure we will reserve the space for the inode item,
1981	 *   it is unnecessary to reserve space for inode ref deletion.
1982	 * - If the inode ref and the inode item are not in the same leaf,
1983	 *   We also needn't worry about enospc problem, because we reserve
1984	 *   much more space for the inode update than it needs.
1985	 * - At the worst, we can steal some space from the global reservation.
1986	 *   It is very rare.
1987	 */
1988	mutex_lock(&delayed_node->mutex);
1989	if (test_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags))
1990		goto release_node;
1991
1992	set_bit(BTRFS_DELAYED_NODE_DEL_IREF, &delayed_node->flags);
1993	delayed_node->count++;
1994	atomic_inc(&fs_info->delayed_root->items);
1995release_node:
1996	mutex_unlock(&delayed_node->mutex);
1997	btrfs_release_delayed_node(delayed_node);
1998	return 0;
1999}
2000
2001static void __btrfs_kill_delayed_node(struct btrfs_delayed_node *delayed_node)
2002{
2003	struct btrfs_root *root = delayed_node->root;
2004	struct btrfs_fs_info *fs_info = root->fs_info;
2005	struct btrfs_delayed_item *curr_item, *prev_item;
2006
2007	mutex_lock(&delayed_node->mutex);
2008	curr_item = __btrfs_first_delayed_insertion_item(delayed_node);
2009	while (curr_item) {
 
2010		prev_item = curr_item;
2011		curr_item = __btrfs_next_delayed_item(prev_item);
2012		btrfs_release_delayed_item(prev_item);
2013	}
2014
2015	if (delayed_node->index_item_leaves > 0) {
2016		btrfs_delayed_item_release_leaves(delayed_node,
2017					  delayed_node->index_item_leaves);
2018		delayed_node->index_item_leaves = 0;
2019	}
2020
2021	curr_item = __btrfs_first_delayed_deletion_item(delayed_node);
2022	while (curr_item) {
2023		btrfs_delayed_item_release_metadata(root, curr_item);
2024		prev_item = curr_item;
2025		curr_item = __btrfs_next_delayed_item(prev_item);
2026		btrfs_release_delayed_item(prev_item);
2027	}
2028
2029	btrfs_release_delayed_iref(delayed_node);
 
2030
2031	if (test_bit(BTRFS_DELAYED_NODE_INODE_DIRTY, &delayed_node->flags)) {
2032		btrfs_delayed_inode_release_metadata(fs_info, delayed_node, false);
2033		btrfs_release_delayed_inode(delayed_node);
2034	}
2035	mutex_unlock(&delayed_node->mutex);
2036}
2037
2038void btrfs_kill_delayed_inode_items(struct btrfs_inode *inode)
2039{
2040	struct btrfs_delayed_node *delayed_node;
2041
2042	delayed_node = btrfs_get_delayed_node(inode);
2043	if (!delayed_node)
2044		return;
2045
2046	__btrfs_kill_delayed_node(delayed_node);
2047	btrfs_release_delayed_node(delayed_node);
2048}
2049
2050void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
2051{
2052	unsigned long index = 0;
2053	struct btrfs_delayed_node *delayed_nodes[8];
 
2054
2055	while (1) {
2056		struct btrfs_delayed_node *node;
2057		int count;
 
 
 
 
 
 
2058
2059		xa_lock(&root->delayed_nodes);
2060		if (xa_empty(&root->delayed_nodes)) {
2061			xa_unlock(&root->delayed_nodes);
2062			return;
2063		}
2064
2065		count = 0;
2066		xa_for_each_start(&root->delayed_nodes, index, node, index) {
2067			/*
2068			 * Don't increase refs in case the node is dead and
2069			 * about to be removed from the tree in the loop below
2070			 */
2071			if (refcount_inc_not_zero(&node->refs)) {
2072				delayed_nodes[count] = node;
2073				count++;
2074			}
2075			if (count >= ARRAY_SIZE(delayed_nodes))
2076				break;
2077		}
2078		xa_unlock(&root->delayed_nodes);
2079		index++;
2080
2081		for (int i = 0; i < count; i++) {
2082			__btrfs_kill_delayed_node(delayed_nodes[i]);
2083			btrfs_release_delayed_node(delayed_nodes[i]);
2084		}
2085	}
2086}
2087
2088void btrfs_destroy_delayed_inodes(struct btrfs_fs_info *fs_info)
2089{
2090	struct btrfs_delayed_node *curr_node, *prev_node;
2091
2092	curr_node = btrfs_first_delayed_node(fs_info->delayed_root);
2093	while (curr_node) {
2094		__btrfs_kill_delayed_node(curr_node);
2095
2096		prev_node = curr_node;
2097		curr_node = btrfs_next_delayed_node(curr_node);
2098		btrfs_release_delayed_node(prev_node);
2099	}
2100}
2101
2102void btrfs_log_get_delayed_items(struct btrfs_inode *inode,
2103				 struct list_head *ins_list,
2104				 struct list_head *del_list)
2105{
2106	struct btrfs_delayed_node *node;
2107	struct btrfs_delayed_item *item;
2108
2109	node = btrfs_get_delayed_node(inode);
2110	if (!node)
2111		return;
2112
2113	mutex_lock(&node->mutex);
2114	item = __btrfs_first_delayed_insertion_item(node);
2115	while (item) {
2116		/*
2117		 * It's possible that the item is already in a log list. This
2118		 * can happen in case two tasks are trying to log the same
2119		 * directory. For example if we have tasks A and task B:
2120		 *
2121		 * Task A collected the delayed items into a log list while
2122		 * under the inode's log_mutex (at btrfs_log_inode()), but it
2123		 * only releases the items after logging the inodes they point
2124		 * to (if they are new inodes), which happens after unlocking
2125		 * the log mutex;
2126		 *
2127		 * Task B enters btrfs_log_inode() and acquires the log_mutex
2128		 * of the same directory inode, before task B releases the
2129		 * delayed items. This can happen for example when logging some
2130		 * inode we need to trigger logging of its parent directory, so
2131		 * logging two files that have the same parent directory can
2132		 * lead to this.
2133		 *
2134		 * If this happens, just ignore delayed items already in a log
2135		 * list. All the tasks logging the directory are under a log
2136		 * transaction and whichever finishes first can not sync the log
2137		 * before the other completes and leaves the log transaction.
2138		 */
2139		if (!item->logged && list_empty(&item->log_list)) {
2140			refcount_inc(&item->refs);
2141			list_add_tail(&item->log_list, ins_list);
2142		}
2143		item = __btrfs_next_delayed_item(item);
2144	}
2145
2146	item = __btrfs_first_delayed_deletion_item(node);
2147	while (item) {
2148		/* It may be non-empty, for the same reason mentioned above. */
2149		if (!item->logged && list_empty(&item->log_list)) {
2150			refcount_inc(&item->refs);
2151			list_add_tail(&item->log_list, del_list);
2152		}
2153		item = __btrfs_next_delayed_item(item);
2154	}
2155	mutex_unlock(&node->mutex);
2156
2157	/*
2158	 * We are called during inode logging, which means the inode is in use
2159	 * and can not be evicted before we finish logging the inode. So we never
2160	 * have the last reference on the delayed inode.
2161	 * Also, we don't use btrfs_release_delayed_node() because that would
2162	 * requeue the delayed inode (change its order in the list of prepared
2163	 * nodes) and we don't want to do such change because we don't create or
2164	 * delete delayed items.
2165	 */
2166	ASSERT(refcount_read(&node->refs) > 1);
2167	refcount_dec(&node->refs);
2168}
2169
2170void btrfs_log_put_delayed_items(struct btrfs_inode *inode,
2171				 struct list_head *ins_list,
2172				 struct list_head *del_list)
2173{
2174	struct btrfs_delayed_node *node;
2175	struct btrfs_delayed_item *item;
2176	struct btrfs_delayed_item *next;
2177
2178	node = btrfs_get_delayed_node(inode);
2179	if (!node)
2180		return;
2181
2182	mutex_lock(&node->mutex);
2183
2184	list_for_each_entry_safe(item, next, ins_list, log_list) {
2185		item->logged = true;
2186		list_del_init(&item->log_list);
2187		if (refcount_dec_and_test(&item->refs))
2188			kfree(item);
2189	}
2190
2191	list_for_each_entry_safe(item, next, del_list, log_list) {
2192		item->logged = true;
2193		list_del_init(&item->log_list);
2194		if (refcount_dec_and_test(&item->refs))
2195			kfree(item);
2196	}
2197
2198	mutex_unlock(&node->mutex);
2199
2200	/*
2201	 * We are called during inode logging, which means the inode is in use
2202	 * and can not be evicted before we finish logging the inode. So we never
2203	 * have the last reference on the delayed inode.
2204	 * Also, we don't use btrfs_release_delayed_node() because that would
2205	 * requeue the delayed inode (change its order in the list of prepared
2206	 * nodes) and we don't want to do such change because we don't create or
2207	 * delete delayed items.
2208	 */
2209	ASSERT(refcount_read(&node->refs) > 1);
2210	refcount_dec(&node->refs);
2211}