Linux Audio

Check our new training course

Loading...
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2007 Oracle.  All rights reserved.
   4 */
   5
   6#include <linux/slab.h>
   7#include <linux/blkdev.h>
   8#include <linux/writeback.h>
   9#include <linux/sched/mm.h>
  10#include "misc.h"
  11#include "ctree.h"
  12#include "transaction.h"
  13#include "btrfs_inode.h"
  14#include "extent_io.h"
  15#include "disk-io.h"
  16#include "compression.h"
  17#include "delalloc-space.h"
 
 
  18
  19static struct kmem_cache *btrfs_ordered_extent_cache;
  20
  21static u64 entry_end(struct btrfs_ordered_extent *entry)
  22{
  23	if (entry->file_offset + entry->len < entry->file_offset)
  24		return (u64)-1;
  25	return entry->file_offset + entry->len;
  26}
  27
  28/* returns NULL if the insertion worked, or it returns the node it did find
  29 * in the tree
  30 */
  31static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
  32				   struct rb_node *node)
  33{
  34	struct rb_node **p = &root->rb_node;
  35	struct rb_node *parent = NULL;
  36	struct btrfs_ordered_extent *entry;
  37
  38	while (*p) {
  39		parent = *p;
  40		entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
  41
  42		if (file_offset < entry->file_offset)
  43			p = &(*p)->rb_left;
  44		else if (file_offset >= entry_end(entry))
  45			p = &(*p)->rb_right;
  46		else
  47			return parent;
  48	}
  49
  50	rb_link_node(node, parent, p);
  51	rb_insert_color(node, root);
  52	return NULL;
  53}
  54
  55static void ordered_data_tree_panic(struct inode *inode, int errno,
  56					       u64 offset)
  57{
  58	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
  59	btrfs_panic(fs_info, errno,
  60		    "Inconsistency in ordered tree at offset %llu", offset);
  61}
  62
  63/*
  64 * look for a given offset in the tree, and if it can't be found return the
  65 * first lesser offset
  66 */
  67static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
  68				     struct rb_node **prev_ret)
  69{
  70	struct rb_node *n = root->rb_node;
  71	struct rb_node *prev = NULL;
  72	struct rb_node *test;
  73	struct btrfs_ordered_extent *entry;
  74	struct btrfs_ordered_extent *prev_entry = NULL;
  75
  76	while (n) {
  77		entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
  78		prev = n;
  79		prev_entry = entry;
  80
  81		if (file_offset < entry->file_offset)
  82			n = n->rb_left;
  83		else if (file_offset >= entry_end(entry))
  84			n = n->rb_right;
  85		else
  86			return n;
  87	}
  88	if (!prev_ret)
  89		return NULL;
  90
  91	while (prev && file_offset >= entry_end(prev_entry)) {
  92		test = rb_next(prev);
  93		if (!test)
  94			break;
  95		prev_entry = rb_entry(test, struct btrfs_ordered_extent,
  96				      rb_node);
  97		if (file_offset < entry_end(prev_entry))
  98			break;
  99
 100		prev = test;
 101	}
 102	if (prev)
 103		prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
 104				      rb_node);
 105	while (prev && file_offset < entry_end(prev_entry)) {
 106		test = rb_prev(prev);
 107		if (!test)
 108			break;
 109		prev_entry = rb_entry(test, struct btrfs_ordered_extent,
 110				      rb_node);
 111		prev = test;
 112	}
 113	*prev_ret = prev;
 114	return NULL;
 115}
 116
 117/*
 118 * helper to check if a given offset is inside a given entry
 119 */
 120static int offset_in_entry(struct btrfs_ordered_extent *entry, u64 file_offset)
 121{
 122	if (file_offset < entry->file_offset ||
 123	    entry->file_offset + entry->len <= file_offset)
 124		return 0;
 125	return 1;
 126}
 127
 128static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
 129			  u64 len)
 130{
 131	if (file_offset + len <= entry->file_offset ||
 132	    entry->file_offset + entry->len <= file_offset)
 133		return 0;
 134	return 1;
 135}
 136
 137/*
 138 * look find the first ordered struct that has this offset, otherwise
 139 * the first one less than this offset
 140 */
 141static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
 142					  u64 file_offset)
 143{
 144	struct rb_root *root = &tree->tree;
 145	struct rb_node *prev = NULL;
 146	struct rb_node *ret;
 147	struct btrfs_ordered_extent *entry;
 148
 149	if (tree->last) {
 150		entry = rb_entry(tree->last, struct btrfs_ordered_extent,
 151				 rb_node);
 152		if (offset_in_entry(entry, file_offset))
 153			return tree->last;
 154	}
 155	ret = __tree_search(root, file_offset, &prev);
 156	if (!ret)
 157		ret = prev;
 158	if (ret)
 159		tree->last = ret;
 160	return ret;
 161}
 162
 163/* allocate and add a new ordered_extent into the per-inode tree.
 164 * file_offset is the logical offset in the file
 165 *
 166 * start is the disk block number of an extent already reserved in the
 167 * extent allocation tree
 168 *
 169 * len is the length of the extent
 170 *
 171 * The tree is given a single reference on the ordered extent that was
 172 * inserted.
 173 */
 174static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 175				      u64 start, u64 len, u64 disk_len,
 176				      int type, int dio, int compress_type)
 
 177{
 178	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 179	struct btrfs_root *root = BTRFS_I(inode)->root;
 180	struct btrfs_ordered_inode_tree *tree;
 181	struct rb_node *node;
 182	struct btrfs_ordered_extent *entry;
 
 183
 184	tree = &BTRFS_I(inode)->ordered_tree;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 185	entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
 186	if (!entry)
 187		return -ENOMEM;
 188
 189	entry->file_offset = file_offset;
 190	entry->start = start;
 191	entry->len = len;
 192	entry->disk_len = disk_len;
 193	entry->bytes_left = len;
 194	entry->inode = igrab(inode);
 195	entry->compress_type = compress_type;
 196	entry->truncated_len = (u64)-1;
 197	if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
 198		set_bit(type, &entry->flags);
 
 
 
 
 
 
 199
 200	if (dio) {
 201		percpu_counter_add_batch(&fs_info->dio_bytes, len,
 202					 fs_info->delalloc_batch);
 
 203		set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
 204	}
 205
 206	/* one ref for the tree */
 207	refcount_set(&entry->refs, 1);
 208	init_waitqueue_head(&entry->wait);
 209	INIT_LIST_HEAD(&entry->list);
 
 210	INIT_LIST_HEAD(&entry->root_extent_list);
 211	INIT_LIST_HEAD(&entry->work_list);
 212	init_completion(&entry->completion);
 213	INIT_LIST_HEAD(&entry->log_list);
 214	INIT_LIST_HEAD(&entry->trans_list);
 215
 216	trace_btrfs_ordered_extent_add(inode, entry);
 217
 218	spin_lock_irq(&tree->lock);
 219	node = tree_insert(&tree->tree, file_offset,
 220			   &entry->rb_node);
 221	if (node)
 222		ordered_data_tree_panic(inode, -EEXIST, file_offset);
 
 
 223	spin_unlock_irq(&tree->lock);
 224
 225	spin_lock(&root->ordered_extent_lock);
 226	list_add_tail(&entry->root_extent_list,
 227		      &root->ordered_extents);
 228	root->nr_ordered_extents++;
 229	if (root->nr_ordered_extents == 1) {
 230		spin_lock(&fs_info->ordered_root_lock);
 231		BUG_ON(!list_empty(&root->ordered_root));
 232		list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
 233		spin_unlock(&fs_info->ordered_root_lock);
 234	}
 235	spin_unlock(&root->ordered_extent_lock);
 236
 237	/*
 238	 * We don't need the count_max_extents here, we can assume that all of
 239	 * that work has been done at higher layers, so this is truly the
 240	 * smallest the extent is going to get.
 241	 */
 242	spin_lock(&BTRFS_I(inode)->lock);
 243	btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
 244	spin_unlock(&BTRFS_I(inode)->lock);
 245
 246	return 0;
 247}
 248
 249int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 250			     u64 start, u64 len, u64 disk_len, int type)
 251{
 252	return __btrfs_add_ordered_extent(inode, file_offset, start, len,
 253					  disk_len, type, 0,
 
 
 
 
 254					  BTRFS_COMPRESS_NONE);
 255}
 256
 257int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
 258				 u64 start, u64 len, u64 disk_len, int type)
 259{
 260	return __btrfs_add_ordered_extent(inode, file_offset, start, len,
 261					  disk_len, type, 1,
 
 
 
 
 262					  BTRFS_COMPRESS_NONE);
 263}
 264
 265int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
 266				      u64 start, u64 len, u64 disk_len,
 267				      int type, int compress_type)
 268{
 269	return __btrfs_add_ordered_extent(inode, file_offset, start, len,
 270					  disk_len, type, 0,
 
 
 271					  compress_type);
 272}
 273
 274/*
 275 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
 276 * when an ordered extent is finished.  If the list covers more than one
 277 * ordered extent, it is split across multiples.
 278 */
 279void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
 280			   struct btrfs_ordered_sum *sum)
 281{
 282	struct btrfs_ordered_inode_tree *tree;
 283
 284	tree = &BTRFS_I(entry->inode)->ordered_tree;
 285	spin_lock_irq(&tree->lock);
 286	list_add_tail(&sum->list, &entry->list);
 287	spin_unlock_irq(&tree->lock);
 288}
 289
 290/*
 291 * this is used to account for finished IO across a given range
 292 * of the file.  The IO may span ordered extents.  If
 293 * a given ordered_extent is completely done, 1 is returned, otherwise
 294 * 0.
 295 *
 296 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
 297 * to make sure this function only returns 1 once for a given ordered extent.
 
 
 
 
 
 
 298 *
 299 * file_offset is updated to one byte past the range that is recorded as
 300 * complete.  This allows you to walk forward in the file.
 301 */
 302int btrfs_dec_test_first_ordered_pending(struct inode *inode,
 303				   struct btrfs_ordered_extent **cached,
 304				   u64 *file_offset, u64 io_size, int uptodate)
 305{
 306	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 307	struct btrfs_ordered_inode_tree *tree;
 
 
 308	struct rb_node *node;
 309	struct btrfs_ordered_extent *entry = NULL;
 310	int ret;
 311	unsigned long flags;
 312	u64 dec_end;
 313	u64 dec_start;
 314	u64 to_dec;
 
 
 
 
 
 
 
 315
 316	tree = &BTRFS_I(inode)->ordered_tree;
 317	spin_lock_irqsave(&tree->lock, flags);
 318	node = tree_search(tree, *file_offset);
 319	if (!node) {
 320		ret = 1;
 321		goto out;
 322	}
 323
 324	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 325	if (!offset_in_entry(entry, *file_offset)) {
 326		ret = 1;
 327		goto out;
 328	}
 329
 330	dec_start = max(*file_offset, entry->file_offset);
 331	dec_end = min(*file_offset + io_size, entry->file_offset +
 332		      entry->len);
 333	*file_offset = dec_end;
 334	if (dec_start > dec_end) {
 335		btrfs_crit(fs_info, "bad ordering dec_start %llu end %llu",
 336			   dec_start, dec_end);
 337	}
 338	to_dec = dec_end - dec_start;
 339	if (to_dec > entry->bytes_left) {
 340		btrfs_crit(fs_info,
 341			   "bad ordered accounting left %llu size %llu",
 342			   entry->bytes_left, to_dec);
 343	}
 344	entry->bytes_left -= to_dec;
 345	if (!uptodate)
 346		set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 347
 348	if (entry->bytes_left == 0) {
 349		ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 350		/* test_and_set_bit implies a barrier */
 351		cond_wake_up_nomb(&entry->wait);
 352	} else {
 353		ret = 1;
 354	}
 355out:
 356	if (!ret && cached && entry) {
 357		*cached = entry;
 358		refcount_inc(&entry->refs);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 359	}
 360	spin_unlock_irqrestore(&tree->lock, flags);
 361	return ret == 0;
 362}
 363
 364/*
 365 * this is used to account for finished IO across a given range
 366 * of the file.  The IO should not span ordered extents.  If
 367 * a given ordered_extent is completely done, 1 is returned, otherwise
 368 * 0.
 369 *
 370 * test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
 371 * to make sure this function only returns 1 once for a given ordered extent.
 
 
 
 
 
 
 
 
 
 
 
 372 */
 373int btrfs_dec_test_ordered_pending(struct inode *inode,
 374				   struct btrfs_ordered_extent **cached,
 375				   u64 file_offset, u64 io_size, int uptodate)
 376{
 377	struct btrfs_ordered_inode_tree *tree;
 378	struct rb_node *node;
 379	struct btrfs_ordered_extent *entry = NULL;
 380	unsigned long flags;
 381	int ret;
 382
 383	tree = &BTRFS_I(inode)->ordered_tree;
 384	spin_lock_irqsave(&tree->lock, flags);
 385	if (cached && *cached) {
 386		entry = *cached;
 387		goto have_entry;
 388	}
 389
 390	node = tree_search(tree, file_offset);
 391	if (!node) {
 392		ret = 1;
 393		goto out;
 394	}
 395
 396	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 397have_entry:
 398	if (!offset_in_entry(entry, file_offset)) {
 399		ret = 1;
 400		goto out;
 401	}
 402
 403	if (io_size > entry->bytes_left) {
 404		btrfs_crit(BTRFS_I(inode)->root->fs_info,
 405			   "bad ordered accounting left %llu size %llu",
 406		       entry->bytes_left, io_size);
 407	}
 408	entry->bytes_left -= io_size;
 409	if (!uptodate)
 410		set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 411
 412	if (entry->bytes_left == 0) {
 413		ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 
 
 
 
 414		/* test_and_set_bit implies a barrier */
 415		cond_wake_up_nomb(&entry->wait);
 416	} else {
 417		ret = 1;
 418	}
 419out:
 420	if (!ret && cached && entry) {
 421		*cached = entry;
 422		refcount_inc(&entry->refs);
 423	}
 424	spin_unlock_irqrestore(&tree->lock, flags);
 425	return ret == 0;
 426}
 427
 428/*
 429 * used to drop a reference on an ordered extent.  This will free
 430 * the extent if the last reference is dropped
 431 */
 432void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 433{
 434	struct list_head *cur;
 435	struct btrfs_ordered_sum *sum;
 436
 437	trace_btrfs_ordered_extent_put(entry->inode, entry);
 438
 439	if (refcount_dec_and_test(&entry->refs)) {
 440		ASSERT(list_empty(&entry->log_list));
 441		ASSERT(list_empty(&entry->trans_list));
 442		ASSERT(list_empty(&entry->root_extent_list));
 
 443		ASSERT(RB_EMPTY_NODE(&entry->rb_node));
 444		if (entry->inode)
 445			btrfs_add_delayed_iput(entry->inode);
 446		while (!list_empty(&entry->list)) {
 447			cur = entry->list.next;
 448			sum = list_entry(cur, struct btrfs_ordered_sum, list);
 449			list_del(&sum->list);
 450			kvfree(sum);
 451		}
 452		kmem_cache_free(btrfs_ordered_extent_cache, entry);
 453	}
 454}
 455
 456/*
 457 * remove an ordered extent from the tree.  No references are dropped
 458 * and waiters are woken up.
 459 */
 460void btrfs_remove_ordered_extent(struct inode *inode,
 461				 struct btrfs_ordered_extent *entry)
 462{
 463	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 464	struct btrfs_ordered_inode_tree *tree;
 465	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
 466	struct btrfs_root *root = btrfs_inode->root;
 
 467	struct rb_node *node;
 
 468
 469	/* This is paired with btrfs_add_ordered_extent. */
 470	spin_lock(&btrfs_inode->lock);
 471	btrfs_mod_outstanding_extents(btrfs_inode, -1);
 472	spin_unlock(&btrfs_inode->lock);
 473	if (root != fs_info->tree_root)
 474		btrfs_delalloc_release_metadata(btrfs_inode, entry->len, false);
 
 475
 476	if (test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
 477		percpu_counter_add_batch(&fs_info->dio_bytes, -entry->len,
 478					 fs_info->delalloc_batch);
 479
 480	tree = &btrfs_inode->ordered_tree;
 481	spin_lock_irq(&tree->lock);
 482	node = &entry->rb_node;
 483	rb_erase(node, &tree->tree);
 484	RB_CLEAR_NODE(node);
 485	if (tree->last == node)
 486		tree->last = NULL;
 487	set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
 
 488	spin_unlock_irq(&tree->lock);
 489
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 490	spin_lock(&root->ordered_extent_lock);
 491	list_del_init(&entry->root_extent_list);
 492	root->nr_ordered_extents--;
 493
 494	trace_btrfs_ordered_extent_remove(inode, entry);
 495
 496	if (!root->nr_ordered_extents) {
 497		spin_lock(&fs_info->ordered_root_lock);
 498		BUG_ON(list_empty(&root->ordered_root));
 499		list_del_init(&root->ordered_root);
 500		spin_unlock(&fs_info->ordered_root_lock);
 501	}
 502	spin_unlock(&root->ordered_extent_lock);
 503	wake_up(&entry->wait);
 504}
 505
 506static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
 507{
 508	struct btrfs_ordered_extent *ordered;
 509
 510	ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
 511	btrfs_start_ordered_extent(ordered->inode, ordered, 1);
 512	complete(&ordered->completion);
 513}
 514
 515/*
 516 * wait for all the ordered extents in a root.  This is done when balancing
 517 * space between drives.
 518 */
 519u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 520			       const u64 range_start, const u64 range_len)
 521{
 522	struct btrfs_fs_info *fs_info = root->fs_info;
 523	LIST_HEAD(splice);
 524	LIST_HEAD(skipped);
 525	LIST_HEAD(works);
 526	struct btrfs_ordered_extent *ordered, *next;
 527	u64 count = 0;
 528	const u64 range_end = range_start + range_len;
 529
 530	mutex_lock(&root->ordered_extent_mutex);
 531	spin_lock(&root->ordered_extent_lock);
 532	list_splice_init(&root->ordered_extents, &splice);
 533	while (!list_empty(&splice) && nr) {
 534		ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
 535					   root_extent_list);
 536
 537		if (range_end <= ordered->start ||
 538		    ordered->start + ordered->disk_len <= range_start) {
 539			list_move_tail(&ordered->root_extent_list, &skipped);
 540			cond_resched_lock(&root->ordered_extent_lock);
 541			continue;
 542		}
 543
 544		list_move_tail(&ordered->root_extent_list,
 545			       &root->ordered_extents);
 546		refcount_inc(&ordered->refs);
 547		spin_unlock(&root->ordered_extent_lock);
 548
 549		btrfs_init_work(&ordered->flush_work,
 550				btrfs_flush_delalloc_helper,
 551				btrfs_run_ordered_extent_work, NULL, NULL);
 552		list_add_tail(&ordered->work_list, &works);
 553		btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
 554
 555		cond_resched();
 556		spin_lock(&root->ordered_extent_lock);
 557		if (nr != U64_MAX)
 558			nr--;
 559		count++;
 560	}
 561	list_splice_tail(&skipped, &root->ordered_extents);
 562	list_splice_tail(&splice, &root->ordered_extents);
 563	spin_unlock(&root->ordered_extent_lock);
 564
 565	list_for_each_entry_safe(ordered, next, &works, work_list) {
 566		list_del_init(&ordered->work_list);
 567		wait_for_completion(&ordered->completion);
 568		btrfs_put_ordered_extent(ordered);
 569		cond_resched();
 570	}
 571	mutex_unlock(&root->ordered_extent_mutex);
 572
 573	return count;
 574}
 575
 576u64 btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 577			     const u64 range_start, const u64 range_len)
 578{
 579	struct btrfs_root *root;
 580	struct list_head splice;
 581	u64 total_done = 0;
 582	u64 done;
 583
 584	INIT_LIST_HEAD(&splice);
 585
 586	mutex_lock(&fs_info->ordered_operations_mutex);
 587	spin_lock(&fs_info->ordered_root_lock);
 588	list_splice_init(&fs_info->ordered_roots, &splice);
 589	while (!list_empty(&splice) && nr) {
 590		root = list_first_entry(&splice, struct btrfs_root,
 591					ordered_root);
 592		root = btrfs_grab_fs_root(root);
 593		BUG_ON(!root);
 594		list_move_tail(&root->ordered_root,
 595			       &fs_info->ordered_roots);
 596		spin_unlock(&fs_info->ordered_root_lock);
 597
 598		done = btrfs_wait_ordered_extents(root, nr,
 599						  range_start, range_len);
 600		btrfs_put_fs_root(root);
 601		total_done += done;
 602
 603		spin_lock(&fs_info->ordered_root_lock);
 604		if (nr != U64_MAX) {
 605			nr -= done;
 606		}
 607	}
 608	list_splice_tail(&splice, &fs_info->ordered_roots);
 609	spin_unlock(&fs_info->ordered_root_lock);
 610	mutex_unlock(&fs_info->ordered_operations_mutex);
 611
 612	return total_done;
 613}
 614
 615/*
 616 * Used to start IO or wait for a given ordered extent to finish.
 617 *
 618 * If wait is one, this effectively waits on page writeback for all the pages
 619 * in the extent, and it waits on the io completion code to insert
 620 * metadata into the btree corresponding to the extent
 621 */
 622void btrfs_start_ordered_extent(struct inode *inode,
 623				       struct btrfs_ordered_extent *entry,
 624				       int wait)
 625{
 626	u64 start = entry->file_offset;
 627	u64 end = start + entry->len - 1;
 
 628
 629	trace_btrfs_ordered_extent_start(inode, entry);
 630
 631	/*
 632	 * pages in the range can be dirty, clean or writeback.  We
 633	 * start IO on any dirty ones so the wait doesn't stall waiting
 634	 * for the flusher thread to find them
 635	 */
 636	if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
 637		filemap_fdatawrite_range(inode->i_mapping, start, end);
 638	if (wait) {
 639		wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
 640						 &entry->flags));
 641	}
 642}
 643
 644/*
 645 * Used to wait on ordered extents across a large range of bytes.
 646 */
 647int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 648{
 649	int ret = 0;
 650	int ret_wb = 0;
 651	u64 end;
 652	u64 orig_end;
 653	struct btrfs_ordered_extent *ordered;
 654
 655	if (start + len < start) {
 656		orig_end = INT_LIMIT(loff_t);
 657	} else {
 658		orig_end = start + len - 1;
 659		if (orig_end > INT_LIMIT(loff_t))
 660			orig_end = INT_LIMIT(loff_t);
 661	}
 662
 663	/* start IO across the range first to instantiate any delalloc
 664	 * extents
 665	 */
 666	ret = btrfs_fdatawrite_range(inode, start, orig_end);
 667	if (ret)
 668		return ret;
 669
 670	/*
 671	 * If we have a writeback error don't return immediately. Wait first
 672	 * for any ordered extents that haven't completed yet. This is to make
 673	 * sure no one can dirty the same page ranges and call writepages()
 674	 * before the ordered extents complete - to avoid failures (-EEXIST)
 675	 * when adding the new ordered extents to the ordered tree.
 676	 */
 677	ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 678
 679	end = orig_end;
 680	while (1) {
 681		ordered = btrfs_lookup_first_ordered_extent(inode, end);
 682		if (!ordered)
 683			break;
 684		if (ordered->file_offset > orig_end) {
 685			btrfs_put_ordered_extent(ordered);
 686			break;
 687		}
 688		if (ordered->file_offset + ordered->len <= start) {
 689			btrfs_put_ordered_extent(ordered);
 690			break;
 691		}
 692		btrfs_start_ordered_extent(inode, ordered, 1);
 693		end = ordered->file_offset;
 
 
 
 
 
 694		if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
 695			ret = -EIO;
 696		btrfs_put_ordered_extent(ordered);
 697		if (ret || end == 0 || end == start)
 698			break;
 699		end--;
 700	}
 701	return ret_wb ? ret_wb : ret;
 702}
 703
 704/*
 705 * find an ordered extent corresponding to file_offset.  return NULL if
 706 * nothing is found, otherwise take a reference on the extent and return it
 707 */
 708struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct inode *inode,
 709							 u64 file_offset)
 710{
 711	struct btrfs_ordered_inode_tree *tree;
 712	struct rb_node *node;
 713	struct btrfs_ordered_extent *entry = NULL;
 
 714
 715	tree = &BTRFS_I(inode)->ordered_tree;
 716	spin_lock_irq(&tree->lock);
 717	node = tree_search(tree, file_offset);
 718	if (!node)
 719		goto out;
 720
 721	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 722	if (!offset_in_entry(entry, file_offset))
 723		entry = NULL;
 724	if (entry)
 725		refcount_inc(&entry->refs);
 726out:
 727	spin_unlock_irq(&tree->lock);
 728	return entry;
 729}
 730
 731/* Since the DIO code tries to lock a wide area we need to look for any ordered
 732 * extents that exist in the range, rather than just the start of the range.
 733 */
 734struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 735		struct btrfs_inode *inode, u64 file_offset, u64 len)
 736{
 737	struct btrfs_ordered_inode_tree *tree;
 738	struct rb_node *node;
 739	struct btrfs_ordered_extent *entry = NULL;
 740
 741	tree = &inode->ordered_tree;
 742	spin_lock_irq(&tree->lock);
 743	node = tree_search(tree, file_offset);
 744	if (!node) {
 745		node = tree_search(tree, file_offset + len);
 746		if (!node)
 747			goto out;
 748	}
 749
 750	while (1) {
 751		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 752		if (range_overlaps(entry, file_offset, len))
 753			break;
 754
 755		if (entry->file_offset >= file_offset + len) {
 756			entry = NULL;
 757			break;
 758		}
 759		entry = NULL;
 760		node = rb_next(node);
 761		if (!node)
 762			break;
 763	}
 764out:
 765	if (entry)
 766		refcount_inc(&entry->refs);
 767	spin_unlock_irq(&tree->lock);
 768	return entry;
 769}
 770
 771/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 772 * lookup and return any extent before 'file_offset'.  NULL is returned
 773 * if none is found
 774 */
 775struct btrfs_ordered_extent *
 776btrfs_lookup_first_ordered_extent(struct inode *inode, u64 file_offset)
 777{
 778	struct btrfs_ordered_inode_tree *tree;
 779	struct rb_node *node;
 780	struct btrfs_ordered_extent *entry = NULL;
 781
 782	tree = &BTRFS_I(inode)->ordered_tree;
 783	spin_lock_irq(&tree->lock);
 784	node = tree_search(tree, file_offset);
 785	if (!node)
 786		goto out;
 787
 788	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 789	refcount_inc(&entry->refs);
 790out:
 791	spin_unlock_irq(&tree->lock);
 792	return entry;
 793}
 794
 795/*
 796 * After an extent is done, call this to conditionally update the on disk
 797 * i_size.  i_size is updated to cover any fully written part of the file.
 
 
 
 
 
 798 */
 799int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
 800				struct btrfs_ordered_extent *ordered)
 801{
 802	struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
 803	u64 disk_i_size;
 804	u64 new_i_size;
 805	u64 i_size = i_size_read(inode);
 806	struct rb_node *node;
 807	struct rb_node *prev = NULL;
 808	struct btrfs_ordered_extent *test;
 809	int ret = 1;
 810	u64 orig_offset = offset;
 811
 812	spin_lock_irq(&tree->lock);
 813	if (ordered) {
 814		offset = entry_end(ordered);
 815		if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags))
 816			offset = min(offset,
 817				     ordered->file_offset +
 818				     ordered->truncated_len);
 819	} else {
 820		offset = ALIGN(offset, btrfs_inode_sectorsize(inode));
 821	}
 822	disk_i_size = BTRFS_I(inode)->disk_i_size;
 823
 824	/*
 825	 * truncate file.
 826	 * If ordered is not NULL, then this is called from endio and
 827	 * disk_i_size will be updated by either truncate itself or any
 828	 * in-flight IOs which are inside the disk_i_size.
 829	 *
 830	 * Because btrfs_setsize() may set i_size with disk_i_size if truncate
 831	 * fails somehow, we need to make sure we have a precise disk_i_size by
 832	 * updating it as usual.
 833	 *
 834	 */
 835	if (!ordered && disk_i_size > i_size) {
 836		BTRFS_I(inode)->disk_i_size = orig_offset;
 837		ret = 0;
 838		goto out;
 839	}
 840
 841	/*
 842	 * if the disk i_size is already at the inode->i_size, or
 843	 * this ordered extent is inside the disk i_size, we're done
 844	 */
 845	if (disk_i_size == i_size)
 846		goto out;
 847
 848	/*
 849	 * We still need to update disk_i_size if outstanding_isize is greater
 850	 * than disk_i_size.
 851	 */
 852	if (offset <= disk_i_size &&
 853	    (!ordered || ordered->outstanding_isize <= disk_i_size))
 854		goto out;
 855
 856	/*
 857	 * walk backward from this ordered extent to disk_i_size.
 858	 * if we find an ordered extent then we can't update disk i_size
 859	 * yet
 860	 */
 861	if (ordered) {
 862		node = rb_prev(&ordered->rb_node);
 863	} else {
 864		prev = tree_search(tree, offset);
 865		/*
 866		 * we insert file extents without involving ordered struct,
 867		 * so there should be no ordered struct cover this offset
 868		 */
 869		if (prev) {
 870			test = rb_entry(prev, struct btrfs_ordered_extent,
 871					rb_node);
 872			BUG_ON(offset_in_entry(test, offset));
 873		}
 874		node = prev;
 875	}
 876	for (; node; node = rb_prev(node)) {
 877		test = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 878
 879		/* We treat this entry as if it doesn't exist */
 880		if (test_bit(BTRFS_ORDERED_UPDATED_ISIZE, &test->flags))
 881			continue;
 882
 883		if (entry_end(test) <= disk_i_size)
 884			break;
 885		if (test->file_offset >= i_size)
 886			break;
 887
 888		/*
 889		 * We don't update disk_i_size now, so record this undealt
 890		 * i_size. Or we will not know the real i_size.
 891		 */
 892		if (test->outstanding_isize < offset)
 893			test->outstanding_isize = offset;
 894		if (ordered &&
 895		    ordered->outstanding_isize > test->outstanding_isize)
 896			test->outstanding_isize = ordered->outstanding_isize;
 897		goto out;
 898	}
 899	new_i_size = min_t(u64, offset, i_size);
 900
 901	/*
 902	 * Some ordered extents may completed before the current one, and
 903	 * we hold the real i_size in ->outstanding_isize.
 904	 */
 905	if (ordered && ordered->outstanding_isize > new_i_size)
 906		new_i_size = min_t(u64, ordered->outstanding_isize, i_size);
 907	BTRFS_I(inode)->disk_i_size = new_i_size;
 908	ret = 0;
 909out:
 910	/*
 911	 * We need to do this because we can't remove ordered extents until
 912	 * after the i_disk_size has been updated and then the inode has been
 913	 * updated to reflect the change, so we need to tell anybody who finds
 914	 * this ordered extent that we've already done all the real work, we
 915	 * just haven't completed all the other work.
 916	 */
 917	if (ordered)
 918		set_bit(BTRFS_ORDERED_UPDATED_ISIZE, &ordered->flags);
 919	spin_unlock_irq(&tree->lock);
 920	return ret;
 921}
 922
 923/*
 924 * search the ordered extents for one corresponding to 'offset' and
 925 * try to find a checksum.  This is used because we allow pages to
 926 * be reclaimed before their checksum is actually put into the btree
 927 */
 928int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr,
 929			   u8 *sum, int len)
 930{
 931	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 932	struct btrfs_ordered_sum *ordered_sum;
 933	struct btrfs_ordered_extent *ordered;
 934	struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
 935	unsigned long num_sectors;
 936	unsigned long i;
 937	u32 sectorsize = btrfs_inode_sectorsize(inode);
 938	const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 939	int index = 0;
 940
 941	ordered = btrfs_lookup_ordered_extent(inode, offset);
 942	if (!ordered)
 943		return 0;
 944
 945	spin_lock_irq(&tree->lock);
 946	list_for_each_entry_reverse(ordered_sum, &ordered->list, list) {
 947		if (disk_bytenr >= ordered_sum->bytenr &&
 948		    disk_bytenr < ordered_sum->bytenr + ordered_sum->len) {
 949			i = (disk_bytenr - ordered_sum->bytenr) >>
 950			    inode->i_sb->s_blocksize_bits;
 951			num_sectors = ordered_sum->len >>
 952				      inode->i_sb->s_blocksize_bits;
 953			num_sectors = min_t(int, len - index, num_sectors - i);
 954			memcpy(sum + index, ordered_sum->sums + i * csum_size,
 955			       num_sectors * csum_size);
 956
 957			index += (int)num_sectors * csum_size;
 958			if (index == len)
 959				goto out;
 960			disk_bytenr += num_sectors * sectorsize;
 961		}
 962	}
 
 
 
 
 
 
 
 
 
 
 
 
 963out:
 
 
 964	spin_unlock_irq(&tree->lock);
 965	btrfs_put_ordered_extent(ordered);
 966	return index;
 967}
 968
 969/*
 970 * btrfs_flush_ordered_range - Lock the passed range and ensures all pending
 971 * ordered extents in it are run to completion.
 972 *
 973 * @tree:         IO tree used for locking out other users of the range
 974 * @inode:        Inode whose ordered tree is to be searched
 975 * @start:        Beginning of range to flush
 976 * @end:          Last byte of range to lock
 977 * @cached_state: If passed, will return the extent state responsible for the
 978 * locked range. It's the caller's responsibility to free the cached state.
 979 *
 980 * This function always returns with the given range locked, ensuring after it's
 981 * called no order extent can be pending.
 982 */
 983void btrfs_lock_and_flush_ordered_range(struct extent_io_tree *tree,
 984					struct btrfs_inode *inode, u64 start,
 985					u64 end,
 986					struct extent_state **cached_state)
 987{
 988	struct btrfs_ordered_extent *ordered;
 989	struct extent_state *cache = NULL;
 990	struct extent_state **cachedp = &cache;
 991
 992	if (cached_state)
 993		cachedp = cached_state;
 994
 995	while (1) {
 996		lock_extent_bits(tree, start, end, cachedp);
 997		ordered = btrfs_lookup_ordered_range(inode, start,
 998						     end - start + 1);
 999		if (!ordered) {
1000			/*
1001			 * If no external cached_state has been passed then
1002			 * decrement the extra ref taken for cachedp since we
1003			 * aren't exposing it outside of this function
1004			 */
1005			if (!cached_state)
1006				refcount_dec(&cache->refs);
1007			break;
1008		}
1009		unlock_extent_cached(tree, start, end, cachedp);
1010		btrfs_start_ordered_extent(&inode->vfs_inode, ordered, 1);
1011		btrfs_put_ordered_extent(ordered);
1012	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1013}
1014
1015int __init ordered_data_init(void)
1016{
1017	btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1018				     sizeof(struct btrfs_ordered_extent), 0,
1019				     SLAB_MEM_SPREAD,
1020				     NULL);
1021	if (!btrfs_ordered_extent_cache)
1022		return -ENOMEM;
1023
1024	return 0;
1025}
1026
1027void __cold ordered_data_exit(void)
1028{
1029	kmem_cache_destroy(btrfs_ordered_extent_cache);
1030}
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2007 Oracle.  All rights reserved.
   4 */
   5
   6#include <linux/slab.h>
   7#include <linux/blkdev.h>
   8#include <linux/writeback.h>
   9#include <linux/sched/mm.h>
  10#include "misc.h"
  11#include "ctree.h"
  12#include "transaction.h"
  13#include "btrfs_inode.h"
  14#include "extent_io.h"
  15#include "disk-io.h"
  16#include "compression.h"
  17#include "delalloc-space.h"
  18#include "qgroup.h"
  19#include "subpage.h"
  20
  21static struct kmem_cache *btrfs_ordered_extent_cache;
  22
  23static u64 entry_end(struct btrfs_ordered_extent *entry)
  24{
  25	if (entry->file_offset + entry->num_bytes < entry->file_offset)
  26		return (u64)-1;
  27	return entry->file_offset + entry->num_bytes;
  28}
  29
  30/* returns NULL if the insertion worked, or it returns the node it did find
  31 * in the tree
  32 */
  33static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
  34				   struct rb_node *node)
  35{
  36	struct rb_node **p = &root->rb_node;
  37	struct rb_node *parent = NULL;
  38	struct btrfs_ordered_extent *entry;
  39
  40	while (*p) {
  41		parent = *p;
  42		entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
  43
  44		if (file_offset < entry->file_offset)
  45			p = &(*p)->rb_left;
  46		else if (file_offset >= entry_end(entry))
  47			p = &(*p)->rb_right;
  48		else
  49			return parent;
  50	}
  51
  52	rb_link_node(node, parent, p);
  53	rb_insert_color(node, root);
  54	return NULL;
  55}
  56
 
 
 
 
 
 
 
 
  57/*
  58 * look for a given offset in the tree, and if it can't be found return the
  59 * first lesser offset
  60 */
  61static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
  62				     struct rb_node **prev_ret)
  63{
  64	struct rb_node *n = root->rb_node;
  65	struct rb_node *prev = NULL;
  66	struct rb_node *test;
  67	struct btrfs_ordered_extent *entry;
  68	struct btrfs_ordered_extent *prev_entry = NULL;
  69
  70	while (n) {
  71		entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
  72		prev = n;
  73		prev_entry = entry;
  74
  75		if (file_offset < entry->file_offset)
  76			n = n->rb_left;
  77		else if (file_offset >= entry_end(entry))
  78			n = n->rb_right;
  79		else
  80			return n;
  81	}
  82	if (!prev_ret)
  83		return NULL;
  84
  85	while (prev && file_offset >= entry_end(prev_entry)) {
  86		test = rb_next(prev);
  87		if (!test)
  88			break;
  89		prev_entry = rb_entry(test, struct btrfs_ordered_extent,
  90				      rb_node);
  91		if (file_offset < entry_end(prev_entry))
  92			break;
  93
  94		prev = test;
  95	}
  96	if (prev)
  97		prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
  98				      rb_node);
  99	while (prev && file_offset < entry_end(prev_entry)) {
 100		test = rb_prev(prev);
 101		if (!test)
 102			break;
 103		prev_entry = rb_entry(test, struct btrfs_ordered_extent,
 104				      rb_node);
 105		prev = test;
 106	}
 107	*prev_ret = prev;
 108	return NULL;
 109}
 110
 
 
 
 
 
 
 
 
 
 
 
 111static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
 112			  u64 len)
 113{
 114	if (file_offset + len <= entry->file_offset ||
 115	    entry->file_offset + entry->num_bytes <= file_offset)
 116		return 0;
 117	return 1;
 118}
 119
 120/*
 121 * look find the first ordered struct that has this offset, otherwise
 122 * the first one less than this offset
 123 */
 124static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
 125					  u64 file_offset)
 126{
 127	struct rb_root *root = &tree->tree;
 128	struct rb_node *prev = NULL;
 129	struct rb_node *ret;
 130	struct btrfs_ordered_extent *entry;
 131
 132	if (tree->last) {
 133		entry = rb_entry(tree->last, struct btrfs_ordered_extent,
 134				 rb_node);
 135		if (in_range(file_offset, entry->file_offset, entry->num_bytes))
 136			return tree->last;
 137	}
 138	ret = __tree_search(root, file_offset, &prev);
 139	if (!ret)
 140		ret = prev;
 141	if (ret)
 142		tree->last = ret;
 143	return ret;
 144}
 145
 146/*
 147 * Allocate and add a new ordered_extent into the per-inode tree.
 
 
 
 
 
 148 *
 149 * The tree is given a single reference on the ordered extent that was
 150 * inserted.
 151 */
 152static int __btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,
 153				      u64 disk_bytenr, u64 num_bytes,
 154				      u64 disk_num_bytes, int type, int dio,
 155				      int compress_type)
 156{
 157	struct btrfs_root *root = inode->root;
 158	struct btrfs_fs_info *fs_info = root->fs_info;
 159	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 160	struct rb_node *node;
 161	struct btrfs_ordered_extent *entry;
 162	int ret;
 163
 164	if (type == BTRFS_ORDERED_NOCOW || type == BTRFS_ORDERED_PREALLOC) {
 165		/* For nocow write, we can release the qgroup rsv right now */
 166		ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes);
 167		if (ret < 0)
 168			return ret;
 169		ret = 0;
 170	} else {
 171		/*
 172		 * The ordered extent has reserved qgroup space, release now
 173		 * and pass the reserved number for qgroup_record to free.
 174		 */
 175		ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes);
 176		if (ret < 0)
 177			return ret;
 178	}
 179	entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
 180	if (!entry)
 181		return -ENOMEM;
 182
 183	entry->file_offset = file_offset;
 184	entry->disk_bytenr = disk_bytenr;
 185	entry->num_bytes = num_bytes;
 186	entry->disk_num_bytes = disk_num_bytes;
 187	entry->bytes_left = num_bytes;
 188	entry->inode = igrab(&inode->vfs_inode);
 189	entry->compress_type = compress_type;
 190	entry->truncated_len = (u64)-1;
 191	entry->qgroup_rsv = ret;
 192	entry->physical = (u64)-1;
 193
 194	ASSERT(type == BTRFS_ORDERED_REGULAR ||
 195	       type == BTRFS_ORDERED_NOCOW ||
 196	       type == BTRFS_ORDERED_PREALLOC ||
 197	       type == BTRFS_ORDERED_COMPRESSED);
 198	set_bit(type, &entry->flags);
 199
 200	percpu_counter_add_batch(&fs_info->ordered_bytes, num_bytes,
 201				 fs_info->delalloc_batch);
 202
 203	if (dio)
 204		set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
 
 205
 206	/* one ref for the tree */
 207	refcount_set(&entry->refs, 1);
 208	init_waitqueue_head(&entry->wait);
 209	INIT_LIST_HEAD(&entry->list);
 210	INIT_LIST_HEAD(&entry->log_list);
 211	INIT_LIST_HEAD(&entry->root_extent_list);
 212	INIT_LIST_HEAD(&entry->work_list);
 213	init_completion(&entry->completion);
 
 
 214
 215	trace_btrfs_ordered_extent_add(inode, entry);
 216
 217	spin_lock_irq(&tree->lock);
 218	node = tree_insert(&tree->tree, file_offset,
 219			   &entry->rb_node);
 220	if (node)
 221		btrfs_panic(fs_info, -EEXIST,
 222				"inconsistency in ordered tree at offset %llu",
 223				file_offset);
 224	spin_unlock_irq(&tree->lock);
 225
 226	spin_lock(&root->ordered_extent_lock);
 227	list_add_tail(&entry->root_extent_list,
 228		      &root->ordered_extents);
 229	root->nr_ordered_extents++;
 230	if (root->nr_ordered_extents == 1) {
 231		spin_lock(&fs_info->ordered_root_lock);
 232		BUG_ON(!list_empty(&root->ordered_root));
 233		list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
 234		spin_unlock(&fs_info->ordered_root_lock);
 235	}
 236	spin_unlock(&root->ordered_extent_lock);
 237
 238	/*
 239	 * We don't need the count_max_extents here, we can assume that all of
 240	 * that work has been done at higher layers, so this is truly the
 241	 * smallest the extent is going to get.
 242	 */
 243	spin_lock(&inode->lock);
 244	btrfs_mod_outstanding_extents(inode, 1);
 245	spin_unlock(&inode->lock);
 246
 247	return 0;
 248}
 249
 250int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,
 251			     u64 disk_bytenr, u64 num_bytes, u64 disk_num_bytes,
 252			     int type)
 253{
 254	ASSERT(type == BTRFS_ORDERED_REGULAR ||
 255	       type == BTRFS_ORDERED_NOCOW ||
 256	       type == BTRFS_ORDERED_PREALLOC);
 257	return __btrfs_add_ordered_extent(inode, file_offset, disk_bytenr,
 258					  num_bytes, disk_num_bytes, type, 0,
 259					  BTRFS_COMPRESS_NONE);
 260}
 261
 262int btrfs_add_ordered_extent_dio(struct btrfs_inode *inode, u64 file_offset,
 263				 u64 disk_bytenr, u64 num_bytes,
 264				 u64 disk_num_bytes, int type)
 265{
 266	ASSERT(type == BTRFS_ORDERED_REGULAR ||
 267	       type == BTRFS_ORDERED_NOCOW ||
 268	       type == BTRFS_ORDERED_PREALLOC);
 269	return __btrfs_add_ordered_extent(inode, file_offset, disk_bytenr,
 270					  num_bytes, disk_num_bytes, type, 1,
 271					  BTRFS_COMPRESS_NONE);
 272}
 273
 274int btrfs_add_ordered_extent_compress(struct btrfs_inode *inode, u64 file_offset,
 275				      u64 disk_bytenr, u64 num_bytes,
 276				      u64 disk_num_bytes, int compress_type)
 277{
 278	ASSERT(compress_type != BTRFS_COMPRESS_NONE);
 279	return __btrfs_add_ordered_extent(inode, file_offset, disk_bytenr,
 280					  num_bytes, disk_num_bytes,
 281					  BTRFS_ORDERED_COMPRESSED, 0,
 282					  compress_type);
 283}
 284
 285/*
 286 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
 287 * when an ordered extent is finished.  If the list covers more than one
 288 * ordered extent, it is split across multiples.
 289 */
 290void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
 291			   struct btrfs_ordered_sum *sum)
 292{
 293	struct btrfs_ordered_inode_tree *tree;
 294
 295	tree = &BTRFS_I(entry->inode)->ordered_tree;
 296	spin_lock_irq(&tree->lock);
 297	list_add_tail(&sum->list, &entry->list);
 298	spin_unlock_irq(&tree->lock);
 299}
 300
 301/*
 302 * Mark all ordered extents io inside the specified range finished.
 
 
 
 303 *
 304 * @page:	 The invovled page for the opeartion.
 305 *		 For uncompressed buffered IO, the page status also needs to be
 306 *		 updated to indicate whether the pending ordered io is finished.
 307 *		 Can be NULL for direct IO and compressed write.
 308 *		 For these cases, callers are ensured they won't execute the
 309 *		 endio function twice.
 310 * @finish_func: The function to be executed when all the IO of an ordered
 311 *		 extent are finished.
 312 *
 313 * This function is called for endio, thus the range must have ordered
 314 * extent(s) coveri it.
 315 */
 316void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
 317				struct page *page, u64 file_offset,
 318				u64 num_bytes, btrfs_func_t finish_func,
 319				bool uptodate)
 320{
 321	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 322	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 323	struct btrfs_workqueue *wq;
 324	struct rb_node *node;
 325	struct btrfs_ordered_extent *entry = NULL;
 
 326	unsigned long flags;
 327	u64 cur = file_offset;
 328
 329	if (btrfs_is_free_space_inode(inode))
 330		wq = fs_info->endio_freespace_worker;
 331	else
 332		wq = fs_info->endio_write_workers;
 333
 334	if (page)
 335		ASSERT(page->mapping && page_offset(page) <= file_offset &&
 336		       file_offset + num_bytes <= page_offset(page) + PAGE_SIZE);
 337
 
 338	spin_lock_irqsave(&tree->lock, flags);
 339	while (cur < file_offset + num_bytes) {
 340		u64 entry_end;
 341		u64 end;
 342		u32 len;
 
 343
 344		node = tree_search(tree, cur);
 345		/* No ordered extents at all */
 346		if (!node)
 347			break;
 
 348
 349		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 350		entry_end = entry->file_offset + entry->num_bytes;
 351		/*
 352		 * |<-- OE --->|  |
 353		 *		  cur
 354		 * Go to next OE.
 355		 */
 356		if (cur >= entry_end) {
 357			node = rb_next(node);
 358			/* No more ordered extents, exit */
 359			if (!node)
 360				break;
 361			entry = rb_entry(node, struct btrfs_ordered_extent,
 362					 rb_node);
 
 
 
 363
 364			/* Go to next ordered extent and continue */
 365			cur = entry->file_offset;
 366			continue;
 367		}
 368		/*
 369		 * |	|<--- OE --->|
 370		 * cur
 371		 * Go to the start of OE.
 372		 */
 373		if (cur < entry->file_offset) {
 374			cur = entry->file_offset;
 375			continue;
 376		}
 377
 378		/*
 379		 * Now we are definitely inside one ordered extent.
 380		 *
 381		 * |<--- OE --->|
 382		 *	|
 383		 *	cur
 384		 */
 385		end = min(entry->file_offset + entry->num_bytes,
 386			  file_offset + num_bytes) - 1;
 387		ASSERT(end + 1 - cur < U32_MAX);
 388		len = end + 1 - cur;
 389
 390		if (page) {
 391			/*
 392			 * Ordered (Private2) bit indicates whether we still
 393			 * have pending io unfinished for the ordered extent.
 394			 *
 395			 * If there's no such bit, we need to skip to next range.
 396			 */
 397			if (!btrfs_page_test_ordered(fs_info, page, cur, len)) {
 398				cur += len;
 399				continue;
 400			}
 401			btrfs_page_clear_ordered(fs_info, page, cur, len);
 402		}
 403
 404		/* Now we're fine to update the accounting */
 405		if (unlikely(len > entry->bytes_left)) {
 406			WARN_ON(1);
 407			btrfs_crit(fs_info,
 408"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%u left=%llu",
 409				   inode->root->root_key.objectid,
 410				   btrfs_ino(inode),
 411				   entry->file_offset,
 412				   entry->num_bytes,
 413				   len, entry->bytes_left);
 414			entry->bytes_left = 0;
 415		} else {
 416			entry->bytes_left -= len;
 417		}
 418
 419		if (!uptodate)
 420			set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 421
 422		/*
 423		 * All the IO of the ordered extent is finished, we need to queue
 424		 * the finish_func to be executed.
 425		 */
 426		if (entry->bytes_left == 0) {
 427			set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 428			cond_wake_up(&entry->wait);
 429			refcount_inc(&entry->refs);
 430			spin_unlock_irqrestore(&tree->lock, flags);
 431			btrfs_init_work(&entry->work, finish_func, NULL, NULL);
 432			btrfs_queue_work(wq, &entry->work);
 433			spin_lock_irqsave(&tree->lock, flags);
 434		}
 435		cur += len;
 436	}
 437	spin_unlock_irqrestore(&tree->lock, flags);
 
 438}
 439
 440/*
 441 * Finish IO for one ordered extent across a given range.  The range can only
 442 * contain one ordered extent.
 
 
 443 *
 444 * @cached:	 The cached ordered extent. If not NULL, we can skip the tree
 445 *               search and use the ordered extent directly.
 446 * 		 Will be also used to store the finished ordered extent.
 447 * @file_offset: File offset for the finished IO
 448 * @io_size:	 Length of the finish IO range
 449 * @uptodate:	 If the IO finishes without problem
 450 *
 451 * Return true if the ordered extent is finished in the range, and update
 452 * @cached.
 453 * Return false otherwise.
 454 *
 455 * NOTE: The range can NOT cross multiple ordered extents.
 456 * Thus caller should ensure the range doesn't cross ordered extents.
 457 */
 458bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
 459				    struct btrfs_ordered_extent **cached,
 460				    u64 file_offset, u64 io_size, int uptodate)
 461{
 462	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 463	struct rb_node *node;
 464	struct btrfs_ordered_extent *entry = NULL;
 465	unsigned long flags;
 466	bool finished = false;
 467
 
 468	spin_lock_irqsave(&tree->lock, flags);
 469	if (cached && *cached) {
 470		entry = *cached;
 471		goto have_entry;
 472	}
 473
 474	node = tree_search(tree, file_offset);
 475	if (!node)
 
 476		goto out;
 
 477
 478	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 479have_entry:
 480	if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 
 481		goto out;
 
 482
 483	if (io_size > entry->bytes_left)
 484		btrfs_crit(inode->root->fs_info,
 485			   "bad ordered accounting left %llu size %llu",
 486		       entry->bytes_left, io_size);
 487
 488	entry->bytes_left -= io_size;
 489	if (!uptodate)
 490		set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 491
 492	if (entry->bytes_left == 0) {
 493		/*
 494		 * Ensure only one caller can set the flag and finished_ret
 495		 * accordingly
 496		 */
 497		finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 498		/* test_and_set_bit implies a barrier */
 499		cond_wake_up_nomb(&entry->wait);
 
 
 500	}
 501out:
 502	if (finished && cached && entry) {
 503		*cached = entry;
 504		refcount_inc(&entry->refs);
 505	}
 506	spin_unlock_irqrestore(&tree->lock, flags);
 507	return finished;
 508}
 509
 510/*
 511 * used to drop a reference on an ordered extent.  This will free
 512 * the extent if the last reference is dropped
 513 */
 514void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 515{
 516	struct list_head *cur;
 517	struct btrfs_ordered_sum *sum;
 518
 519	trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
 520
 521	if (refcount_dec_and_test(&entry->refs)) {
 
 
 522		ASSERT(list_empty(&entry->root_extent_list));
 523		ASSERT(list_empty(&entry->log_list));
 524		ASSERT(RB_EMPTY_NODE(&entry->rb_node));
 525		if (entry->inode)
 526			btrfs_add_delayed_iput(entry->inode);
 527		while (!list_empty(&entry->list)) {
 528			cur = entry->list.next;
 529			sum = list_entry(cur, struct btrfs_ordered_sum, list);
 530			list_del(&sum->list);
 531			kvfree(sum);
 532		}
 533		kmem_cache_free(btrfs_ordered_extent_cache, entry);
 534	}
 535}
 536
 537/*
 538 * remove an ordered extent from the tree.  No references are dropped
 539 * and waiters are woken up.
 540 */
 541void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
 542				 struct btrfs_ordered_extent *entry)
 543{
 
 544	struct btrfs_ordered_inode_tree *tree;
 
 545	struct btrfs_root *root = btrfs_inode->root;
 546	struct btrfs_fs_info *fs_info = root->fs_info;
 547	struct rb_node *node;
 548	bool pending;
 549
 550	/* This is paired with btrfs_add_ordered_extent. */
 551	spin_lock(&btrfs_inode->lock);
 552	btrfs_mod_outstanding_extents(btrfs_inode, -1);
 553	spin_unlock(&btrfs_inode->lock);
 554	if (root != fs_info->tree_root)
 555		btrfs_delalloc_release_metadata(btrfs_inode, entry->num_bytes,
 556						false);
 557
 558	percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
 559				 fs_info->delalloc_batch);
 
 560
 561	tree = &btrfs_inode->ordered_tree;
 562	spin_lock_irq(&tree->lock);
 563	node = &entry->rb_node;
 564	rb_erase(node, &tree->tree);
 565	RB_CLEAR_NODE(node);
 566	if (tree->last == node)
 567		tree->last = NULL;
 568	set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
 569	pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
 570	spin_unlock_irq(&tree->lock);
 571
 572	/*
 573	 * The current running transaction is waiting on us, we need to let it
 574	 * know that we're complete and wake it up.
 575	 */
 576	if (pending) {
 577		struct btrfs_transaction *trans;
 578
 579		/*
 580		 * The checks for trans are just a formality, it should be set,
 581		 * but if it isn't we don't want to deref/assert under the spin
 582		 * lock, so be nice and check if trans is set, but ASSERT() so
 583		 * if it isn't set a developer will notice.
 584		 */
 585		spin_lock(&fs_info->trans_lock);
 586		trans = fs_info->running_transaction;
 587		if (trans)
 588			refcount_inc(&trans->use_count);
 589		spin_unlock(&fs_info->trans_lock);
 590
 591		ASSERT(trans);
 592		if (trans) {
 593			if (atomic_dec_and_test(&trans->pending_ordered))
 594				wake_up(&trans->pending_wait);
 595			btrfs_put_transaction(trans);
 596		}
 597	}
 598
 599	spin_lock(&root->ordered_extent_lock);
 600	list_del_init(&entry->root_extent_list);
 601	root->nr_ordered_extents--;
 602
 603	trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
 604
 605	if (!root->nr_ordered_extents) {
 606		spin_lock(&fs_info->ordered_root_lock);
 607		BUG_ON(list_empty(&root->ordered_root));
 608		list_del_init(&root->ordered_root);
 609		spin_unlock(&fs_info->ordered_root_lock);
 610	}
 611	spin_unlock(&root->ordered_extent_lock);
 612	wake_up(&entry->wait);
 613}
 614
 615static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
 616{
 617	struct btrfs_ordered_extent *ordered;
 618
 619	ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
 620	btrfs_start_ordered_extent(ordered, 1);
 621	complete(&ordered->completion);
 622}
 623
 624/*
 625 * wait for all the ordered extents in a root.  This is done when balancing
 626 * space between drives.
 627 */
 628u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 629			       const u64 range_start, const u64 range_len)
 630{
 631	struct btrfs_fs_info *fs_info = root->fs_info;
 632	LIST_HEAD(splice);
 633	LIST_HEAD(skipped);
 634	LIST_HEAD(works);
 635	struct btrfs_ordered_extent *ordered, *next;
 636	u64 count = 0;
 637	const u64 range_end = range_start + range_len;
 638
 639	mutex_lock(&root->ordered_extent_mutex);
 640	spin_lock(&root->ordered_extent_lock);
 641	list_splice_init(&root->ordered_extents, &splice);
 642	while (!list_empty(&splice) && nr) {
 643		ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
 644					   root_extent_list);
 645
 646		if (range_end <= ordered->disk_bytenr ||
 647		    ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
 648			list_move_tail(&ordered->root_extent_list, &skipped);
 649			cond_resched_lock(&root->ordered_extent_lock);
 650			continue;
 651		}
 652
 653		list_move_tail(&ordered->root_extent_list,
 654			       &root->ordered_extents);
 655		refcount_inc(&ordered->refs);
 656		spin_unlock(&root->ordered_extent_lock);
 657
 658		btrfs_init_work(&ordered->flush_work,
 
 659				btrfs_run_ordered_extent_work, NULL, NULL);
 660		list_add_tail(&ordered->work_list, &works);
 661		btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
 662
 663		cond_resched();
 664		spin_lock(&root->ordered_extent_lock);
 665		if (nr != U64_MAX)
 666			nr--;
 667		count++;
 668	}
 669	list_splice_tail(&skipped, &root->ordered_extents);
 670	list_splice_tail(&splice, &root->ordered_extents);
 671	spin_unlock(&root->ordered_extent_lock);
 672
 673	list_for_each_entry_safe(ordered, next, &works, work_list) {
 674		list_del_init(&ordered->work_list);
 675		wait_for_completion(&ordered->completion);
 676		btrfs_put_ordered_extent(ordered);
 677		cond_resched();
 678	}
 679	mutex_unlock(&root->ordered_extent_mutex);
 680
 681	return count;
 682}
 683
 684void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 685			     const u64 range_start, const u64 range_len)
 686{
 687	struct btrfs_root *root;
 688	struct list_head splice;
 
 689	u64 done;
 690
 691	INIT_LIST_HEAD(&splice);
 692
 693	mutex_lock(&fs_info->ordered_operations_mutex);
 694	spin_lock(&fs_info->ordered_root_lock);
 695	list_splice_init(&fs_info->ordered_roots, &splice);
 696	while (!list_empty(&splice) && nr) {
 697		root = list_first_entry(&splice, struct btrfs_root,
 698					ordered_root);
 699		root = btrfs_grab_root(root);
 700		BUG_ON(!root);
 701		list_move_tail(&root->ordered_root,
 702			       &fs_info->ordered_roots);
 703		spin_unlock(&fs_info->ordered_root_lock);
 704
 705		done = btrfs_wait_ordered_extents(root, nr,
 706						  range_start, range_len);
 707		btrfs_put_root(root);
 
 708
 709		spin_lock(&fs_info->ordered_root_lock);
 710		if (nr != U64_MAX) {
 711			nr -= done;
 712		}
 713	}
 714	list_splice_tail(&splice, &fs_info->ordered_roots);
 715	spin_unlock(&fs_info->ordered_root_lock);
 716	mutex_unlock(&fs_info->ordered_operations_mutex);
 
 
 717}
 718
 719/*
 720 * Used to start IO or wait for a given ordered extent to finish.
 721 *
 722 * If wait is one, this effectively waits on page writeback for all the pages
 723 * in the extent, and it waits on the io completion code to insert
 724 * metadata into the btree corresponding to the extent
 725 */
 726void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry, int wait)
 
 
 727{
 728	u64 start = entry->file_offset;
 729	u64 end = start + entry->num_bytes - 1;
 730	struct btrfs_inode *inode = BTRFS_I(entry->inode);
 731
 732	trace_btrfs_ordered_extent_start(inode, entry);
 733
 734	/*
 735	 * pages in the range can be dirty, clean or writeback.  We
 736	 * start IO on any dirty ones so the wait doesn't stall waiting
 737	 * for the flusher thread to find them
 738	 */
 739	if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
 740		filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
 741	if (wait) {
 742		wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
 743						 &entry->flags));
 744	}
 745}
 746
 747/*
 748 * Used to wait on ordered extents across a large range of bytes.
 749 */
 750int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 751{
 752	int ret = 0;
 753	int ret_wb = 0;
 754	u64 end;
 755	u64 orig_end;
 756	struct btrfs_ordered_extent *ordered;
 757
 758	if (start + len < start) {
 759		orig_end = INT_LIMIT(loff_t);
 760	} else {
 761		orig_end = start + len - 1;
 762		if (orig_end > INT_LIMIT(loff_t))
 763			orig_end = INT_LIMIT(loff_t);
 764	}
 765
 766	/* start IO across the range first to instantiate any delalloc
 767	 * extents
 768	 */
 769	ret = btrfs_fdatawrite_range(inode, start, orig_end);
 770	if (ret)
 771		return ret;
 772
 773	/*
 774	 * If we have a writeback error don't return immediately. Wait first
 775	 * for any ordered extents that haven't completed yet. This is to make
 776	 * sure no one can dirty the same page ranges and call writepages()
 777	 * before the ordered extents complete - to avoid failures (-EEXIST)
 778	 * when adding the new ordered extents to the ordered tree.
 779	 */
 780	ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 781
 782	end = orig_end;
 783	while (1) {
 784		ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
 785		if (!ordered)
 786			break;
 787		if (ordered->file_offset > orig_end) {
 788			btrfs_put_ordered_extent(ordered);
 789			break;
 790		}
 791		if (ordered->file_offset + ordered->num_bytes <= start) {
 792			btrfs_put_ordered_extent(ordered);
 793			break;
 794		}
 795		btrfs_start_ordered_extent(ordered, 1);
 796		end = ordered->file_offset;
 797		/*
 798		 * If the ordered extent had an error save the error but don't
 799		 * exit without waiting first for all other ordered extents in
 800		 * the range to complete.
 801		 */
 802		if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
 803			ret = -EIO;
 804		btrfs_put_ordered_extent(ordered);
 805		if (end == 0 || end == start)
 806			break;
 807		end--;
 808	}
 809	return ret_wb ? ret_wb : ret;
 810}
 811
 812/*
 813 * find an ordered extent corresponding to file_offset.  return NULL if
 814 * nothing is found, otherwise take a reference on the extent and return it
 815 */
 816struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
 817							 u64 file_offset)
 818{
 819	struct btrfs_ordered_inode_tree *tree;
 820	struct rb_node *node;
 821	struct btrfs_ordered_extent *entry = NULL;
 822	unsigned long flags;
 823
 824	tree = &inode->ordered_tree;
 825	spin_lock_irqsave(&tree->lock, flags);
 826	node = tree_search(tree, file_offset);
 827	if (!node)
 828		goto out;
 829
 830	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 831	if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 832		entry = NULL;
 833	if (entry)
 834		refcount_inc(&entry->refs);
 835out:
 836	spin_unlock_irqrestore(&tree->lock, flags);
 837	return entry;
 838}
 839
 840/* Since the DIO code tries to lock a wide area we need to look for any ordered
 841 * extents that exist in the range, rather than just the start of the range.
 842 */
 843struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 844		struct btrfs_inode *inode, u64 file_offset, u64 len)
 845{
 846	struct btrfs_ordered_inode_tree *tree;
 847	struct rb_node *node;
 848	struct btrfs_ordered_extent *entry = NULL;
 849
 850	tree = &inode->ordered_tree;
 851	spin_lock_irq(&tree->lock);
 852	node = tree_search(tree, file_offset);
 853	if (!node) {
 854		node = tree_search(tree, file_offset + len);
 855		if (!node)
 856			goto out;
 857	}
 858
 859	while (1) {
 860		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 861		if (range_overlaps(entry, file_offset, len))
 862			break;
 863
 864		if (entry->file_offset >= file_offset + len) {
 865			entry = NULL;
 866			break;
 867		}
 868		entry = NULL;
 869		node = rb_next(node);
 870		if (!node)
 871			break;
 872	}
 873out:
 874	if (entry)
 875		refcount_inc(&entry->refs);
 876	spin_unlock_irq(&tree->lock);
 877	return entry;
 878}
 879
 880/*
 881 * Adds all ordered extents to the given list. The list ends up sorted by the
 882 * file_offset of the ordered extents.
 883 */
 884void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
 885					   struct list_head *list)
 886{
 887	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 888	struct rb_node *n;
 889
 890	ASSERT(inode_is_locked(&inode->vfs_inode));
 891
 892	spin_lock_irq(&tree->lock);
 893	for (n = rb_first(&tree->tree); n; n = rb_next(n)) {
 894		struct btrfs_ordered_extent *ordered;
 895
 896		ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
 897
 898		if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
 899			continue;
 900
 901		ASSERT(list_empty(&ordered->log_list));
 902		list_add_tail(&ordered->log_list, list);
 903		refcount_inc(&ordered->refs);
 904	}
 905	spin_unlock_irq(&tree->lock);
 906}
 907
 908/*
 909 * lookup and return any extent before 'file_offset'.  NULL is returned
 910 * if none is found
 911 */
 912struct btrfs_ordered_extent *
 913btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
 914{
 915	struct btrfs_ordered_inode_tree *tree;
 916	struct rb_node *node;
 917	struct btrfs_ordered_extent *entry = NULL;
 918
 919	tree = &inode->ordered_tree;
 920	spin_lock_irq(&tree->lock);
 921	node = tree_search(tree, file_offset);
 922	if (!node)
 923		goto out;
 924
 925	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 926	refcount_inc(&entry->refs);
 927out:
 928	spin_unlock_irq(&tree->lock);
 929	return entry;
 930}
 931
 932/*
 933 * Lookup the first ordered extent that overlaps the range
 934 * [@file_offset, @file_offset + @len).
 935 *
 936 * The difference between this and btrfs_lookup_first_ordered_extent() is
 937 * that this one won't return any ordered extent that does not overlap the range.
 938 * And the difference against btrfs_lookup_ordered_extent() is, this function
 939 * ensures the first ordered extent gets returned.
 940 */
 941struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
 942			struct btrfs_inode *inode, u64 file_offset, u64 len)
 943{
 944	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 
 
 
 945	struct rb_node *node;
 946	struct rb_node *cur;
 947	struct rb_node *prev;
 948	struct rb_node *next;
 949	struct btrfs_ordered_extent *entry = NULL;
 950
 951	spin_lock_irq(&tree->lock);
 952	node = tree->tree.rb_node;
 
 
 
 
 
 
 
 
 
 
 953	/*
 954	 * Here we don't want to use tree_search() which will use tree->last
 955	 * and screw up the search order.
 956	 * And __tree_search() can't return the adjacent ordered extents
 957	 * either, thus here we do our own search.
 
 
 
 
 
 958	 */
 959	while (node) {
 960		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 961
 962		if (file_offset < entry->file_offset) {
 963			node = node->rb_left;
 964		} else if (file_offset >= entry_end(entry)) {
 965			node = node->rb_right;
 966		} else {
 967			/*
 968			 * Direct hit, got an ordered extent that starts at
 969			 * @file_offset
 970			 */
 971			goto out;
 
 
 
 
 
 
 
 972		}
 
 973	}
 974	if (!entry) {
 975		/* Empty tree */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 976		goto out;
 977	}
 
 978
 979	cur = &entry->rb_node;
 980	/* We got an entry around @file_offset, check adjacent entries */
 981	if (entry->file_offset < file_offset) {
 982		prev = cur;
 983		next = rb_next(cur);
 984	} else {
 985		prev = rb_prev(cur);
 986		next = cur;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 987	}
 988	if (prev) {
 989		entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
 990		if (range_overlaps(entry, file_offset, len))
 991			goto out;
 992	}
 993	if (next) {
 994		entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
 995		if (range_overlaps(entry, file_offset, len))
 996			goto out;
 997	}
 998	/* No ordered extent in the range */
 999	entry = NULL;
1000out:
1001	if (entry)
1002		refcount_inc(&entry->refs);
1003	spin_unlock_irq(&tree->lock);
1004	return entry;
 
1005}
1006
1007/*
1008 * btrfs_flush_ordered_range - Lock the passed range and ensures all pending
1009 * ordered extents in it are run to completion.
1010 *
 
1011 * @inode:        Inode whose ordered tree is to be searched
1012 * @start:        Beginning of range to flush
1013 * @end:          Last byte of range to lock
1014 * @cached_state: If passed, will return the extent state responsible for the
1015 * locked range. It's the caller's responsibility to free the cached state.
1016 *
1017 * This function always returns with the given range locked, ensuring after it's
1018 * called no order extent can be pending.
1019 */
1020void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
 
1021					u64 end,
1022					struct extent_state **cached_state)
1023{
1024	struct btrfs_ordered_extent *ordered;
1025	struct extent_state *cache = NULL;
1026	struct extent_state **cachedp = &cache;
1027
1028	if (cached_state)
1029		cachedp = cached_state;
1030
1031	while (1) {
1032		lock_extent_bits(&inode->io_tree, start, end, cachedp);
1033		ordered = btrfs_lookup_ordered_range(inode, start,
1034						     end - start + 1);
1035		if (!ordered) {
1036			/*
1037			 * If no external cached_state has been passed then
1038			 * decrement the extra ref taken for cachedp since we
1039			 * aren't exposing it outside of this function
1040			 */
1041			if (!cached_state)
1042				refcount_dec(&cache->refs);
1043			break;
1044		}
1045		unlock_extent_cached(&inode->io_tree, start, end, cachedp);
1046		btrfs_start_ordered_extent(ordered, 1);
1047		btrfs_put_ordered_extent(ordered);
1048	}
1049}
1050
1051static int clone_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pos,
1052				u64 len)
1053{
1054	struct inode *inode = ordered->inode;
1055	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1056	u64 file_offset = ordered->file_offset + pos;
1057	u64 disk_bytenr = ordered->disk_bytenr + pos;
1058	u64 num_bytes = len;
1059	u64 disk_num_bytes = len;
1060	int type;
1061	unsigned long flags_masked = ordered->flags & ~(1 << BTRFS_ORDERED_DIRECT);
1062	int compress_type = ordered->compress_type;
1063	unsigned long weight;
1064	int ret;
1065
1066	weight = hweight_long(flags_masked);
1067	WARN_ON_ONCE(weight > 1);
1068	if (!weight)
1069		type = 0;
1070	else
1071		type = __ffs(flags_masked);
1072
1073	/*
1074	 * The splitting extent is already counted and will be added again
1075	 * in btrfs_add_ordered_extent_*(). Subtract num_bytes to avoid
1076	 * double counting.
1077	 */
1078	percpu_counter_add_batch(&fs_info->ordered_bytes, -num_bytes,
1079				 fs_info->delalloc_batch);
1080	if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered->flags)) {
1081		WARN_ON_ONCE(1);
1082		ret = btrfs_add_ordered_extent_compress(BTRFS_I(inode),
1083				file_offset, disk_bytenr, num_bytes,
1084				disk_num_bytes, compress_type);
1085	} else if (test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
1086		ret = btrfs_add_ordered_extent_dio(BTRFS_I(inode), file_offset,
1087				disk_bytenr, num_bytes, disk_num_bytes, type);
1088	} else {
1089		ret = btrfs_add_ordered_extent(BTRFS_I(inode), file_offset,
1090				disk_bytenr, num_bytes, disk_num_bytes, type);
1091	}
1092
1093	return ret;
1094}
1095
1096int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre,
1097				u64 post)
1098{
1099	struct inode *inode = ordered->inode;
1100	struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
1101	struct rb_node *node;
1102	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1103	int ret = 0;
1104
1105	spin_lock_irq(&tree->lock);
1106	/* Remove from tree once */
1107	node = &ordered->rb_node;
1108	rb_erase(node, &tree->tree);
1109	RB_CLEAR_NODE(node);
1110	if (tree->last == node)
1111		tree->last = NULL;
1112
1113	ordered->file_offset += pre;
1114	ordered->disk_bytenr += pre;
1115	ordered->num_bytes -= (pre + post);
1116	ordered->disk_num_bytes -= (pre + post);
1117	ordered->bytes_left -= (pre + post);
1118
1119	/* Re-insert the node */
1120	node = tree_insert(&tree->tree, ordered->file_offset, &ordered->rb_node);
1121	if (node)
1122		btrfs_panic(fs_info, -EEXIST,
1123			"zoned: inconsistency in ordered tree at offset %llu",
1124			    ordered->file_offset);
1125
1126	spin_unlock_irq(&tree->lock);
1127
1128	if (pre)
1129		ret = clone_ordered_extent(ordered, 0, pre);
1130	if (ret == 0 && post)
1131		ret = clone_ordered_extent(ordered, pre + ordered->disk_num_bytes,
1132					   post);
1133
1134	return ret;
1135}
1136
1137int __init ordered_data_init(void)
1138{
1139	btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1140				     sizeof(struct btrfs_ordered_extent), 0,
1141				     SLAB_MEM_SPREAD,
1142				     NULL);
1143	if (!btrfs_ordered_extent_cache)
1144		return -ENOMEM;
1145
1146	return 0;
1147}
1148
1149void __cold ordered_data_exit(void)
1150{
1151	kmem_cache_destroy(btrfs_ordered_extent_cache);
1152}