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v6.2
   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 "messages.h"
  11#include "misc.h"
  12#include "ctree.h"
  13#include "transaction.h"
  14#include "btrfs_inode.h"
  15#include "extent_io.h"
  16#include "disk-io.h"
  17#include "compression.h"
  18#include "delalloc-space.h"
  19#include "qgroup.h"
  20#include "subpage.h"
  21#include "file.h"
  22#include "super.h"
  23
  24static struct kmem_cache *btrfs_ordered_extent_cache;
  25
  26static u64 entry_end(struct btrfs_ordered_extent *entry)
  27{
  28	if (entry->file_offset + entry->num_bytes < entry->file_offset)
  29		return (u64)-1;
  30	return entry->file_offset + entry->num_bytes;
  31}
  32
  33/* returns NULL if the insertion worked, or it returns the node it did find
  34 * in the tree
  35 */
  36static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
  37				   struct rb_node *node)
  38{
  39	struct rb_node **p = &root->rb_node;
  40	struct rb_node *parent = NULL;
  41	struct btrfs_ordered_extent *entry;
  42
  43	while (*p) {
  44		parent = *p;
  45		entry = rb_entry(parent, struct btrfs_ordered_extent, rb_node);
  46
  47		if (file_offset < entry->file_offset)
  48			p = &(*p)->rb_left;
  49		else if (file_offset >= entry_end(entry))
  50			p = &(*p)->rb_right;
  51		else
  52			return parent;
  53	}
  54
  55	rb_link_node(node, parent, p);
  56	rb_insert_color(node, root);
  57	return NULL;
  58}
  59
  60/*
  61 * look for a given offset in the tree, and if it can't be found return the
  62 * first lesser offset
  63 */
  64static struct rb_node *__tree_search(struct rb_root *root, u64 file_offset,
  65				     struct rb_node **prev_ret)
  66{
  67	struct rb_node *n = root->rb_node;
  68	struct rb_node *prev = NULL;
  69	struct rb_node *test;
  70	struct btrfs_ordered_extent *entry;
  71	struct btrfs_ordered_extent *prev_entry = NULL;
  72
  73	while (n) {
  74		entry = rb_entry(n, struct btrfs_ordered_extent, rb_node);
  75		prev = n;
  76		prev_entry = entry;
  77
  78		if (file_offset < entry->file_offset)
  79			n = n->rb_left;
  80		else if (file_offset >= entry_end(entry))
  81			n = n->rb_right;
  82		else
  83			return n;
  84	}
  85	if (!prev_ret)
  86		return NULL;
  87
  88	while (prev && file_offset >= entry_end(prev_entry)) {
  89		test = rb_next(prev);
  90		if (!test)
  91			break;
  92		prev_entry = rb_entry(test, struct btrfs_ordered_extent,
  93				      rb_node);
  94		if (file_offset < entry_end(prev_entry))
  95			break;
  96
  97		prev = test;
  98	}
  99	if (prev)
 100		prev_entry = rb_entry(prev, struct btrfs_ordered_extent,
 101				      rb_node);
 102	while (prev && file_offset < entry_end(prev_entry)) {
 103		test = rb_prev(prev);
 104		if (!test)
 105			break;
 106		prev_entry = rb_entry(test, struct btrfs_ordered_extent,
 107				      rb_node);
 108		prev = test;
 109	}
 110	*prev_ret = prev;
 111	return NULL;
 112}
 113
 114static int range_overlaps(struct btrfs_ordered_extent *entry, u64 file_offset,
 115			  u64 len)
 116{
 117	if (file_offset + len <= entry->file_offset ||
 118	    entry->file_offset + entry->num_bytes <= file_offset)
 119		return 0;
 120	return 1;
 121}
 122
 123/*
 124 * look find the first ordered struct that has this offset, otherwise
 125 * the first one less than this offset
 126 */
 127static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
 128					  u64 file_offset)
 129{
 130	struct rb_root *root = &tree->tree;
 131	struct rb_node *prev = NULL;
 132	struct rb_node *ret;
 133	struct btrfs_ordered_extent *entry;
 134
 135	if (tree->last) {
 136		entry = rb_entry(tree->last, struct btrfs_ordered_extent,
 137				 rb_node);
 138		if (in_range(file_offset, entry->file_offset, entry->num_bytes))
 139			return tree->last;
 140	}
 141	ret = __tree_search(root, file_offset, &prev);
 142	if (!ret)
 143		ret = prev;
 144	if (ret)
 145		tree->last = ret;
 146	return ret;
 147}
 148
 149/*
 150 * Add an ordered extent to the per-inode tree.
 151 *
 152 * @inode:           Inode that this extent is for.
 153 * @file_offset:     Logical offset in file where the extent starts.
 154 * @num_bytes:       Logical length of extent in file.
 155 * @ram_bytes:       Full length of unencoded data.
 156 * @disk_bytenr:     Offset of extent on disk.
 157 * @disk_num_bytes:  Size of extent on disk.
 158 * @offset:          Offset into unencoded data where file data starts.
 159 * @flags:           Flags specifying type of extent (1 << BTRFS_ORDERED_*).
 160 * @compress_type:   Compression algorithm used for data.
 161 *
 162 * Most of these parameters correspond to &struct btrfs_file_extent_item. The
 163 * tree is given a single reference on the ordered extent that was inserted.
 164 *
 165 * Return: 0 or -ENOMEM.
 166 */
 167int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,
 168			     u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,
 169			     u64 disk_num_bytes, u64 offset, unsigned flags,
 170			     int compress_type)
 171{
 172	struct btrfs_root *root = inode->root;
 173	struct btrfs_fs_info *fs_info = root->fs_info;
 174	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 175	struct rb_node *node;
 176	struct btrfs_ordered_extent *entry;
 177	int ret;
 178
 179	if (flags &
 180	    ((1 << BTRFS_ORDERED_NOCOW) | (1 << BTRFS_ORDERED_PREALLOC))) {
 181		/* For nocow write, we can release the qgroup rsv right now */
 182		ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes);
 183		if (ret < 0)
 184			return ret;
 185		ret = 0;
 186	} else {
 187		/*
 188		 * The ordered extent has reserved qgroup space, release now
 189		 * and pass the reserved number for qgroup_record to free.
 190		 */
 191		ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes);
 192		if (ret < 0)
 193			return ret;
 194	}
 195	entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);
 196	if (!entry)
 197		return -ENOMEM;
 198
 199	entry->file_offset = file_offset;
 200	entry->num_bytes = num_bytes;
 201	entry->ram_bytes = ram_bytes;
 202	entry->disk_bytenr = disk_bytenr;
 
 203	entry->disk_num_bytes = disk_num_bytes;
 204	entry->offset = offset;
 205	entry->bytes_left = num_bytes;
 206	entry->inode = igrab(&inode->vfs_inode);
 207	entry->compress_type = compress_type;
 208	entry->truncated_len = (u64)-1;
 209	entry->qgroup_rsv = ret;
 210	entry->physical = (u64)-1;
 211
 212	ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
 213	entry->flags = flags;
 
 
 
 214
 215	percpu_counter_add_batch(&fs_info->ordered_bytes, num_bytes,
 216				 fs_info->delalloc_batch);
 217
 
 
 
 218	/* one ref for the tree */
 219	refcount_set(&entry->refs, 1);
 220	init_waitqueue_head(&entry->wait);
 221	INIT_LIST_HEAD(&entry->list);
 222	INIT_LIST_HEAD(&entry->log_list);
 223	INIT_LIST_HEAD(&entry->root_extent_list);
 224	INIT_LIST_HEAD(&entry->work_list);
 225	init_completion(&entry->completion);
 226
 227	trace_btrfs_ordered_extent_add(inode, entry);
 228
 229	spin_lock_irq(&tree->lock);
 230	node = tree_insert(&tree->tree, file_offset,
 231			   &entry->rb_node);
 232	if (node)
 233		btrfs_panic(fs_info, -EEXIST,
 234				"inconsistency in ordered tree at offset %llu",
 235				file_offset);
 236	spin_unlock_irq(&tree->lock);
 237
 238	spin_lock(&root->ordered_extent_lock);
 239	list_add_tail(&entry->root_extent_list,
 240		      &root->ordered_extents);
 241	root->nr_ordered_extents++;
 242	if (root->nr_ordered_extents == 1) {
 243		spin_lock(&fs_info->ordered_root_lock);
 244		BUG_ON(!list_empty(&root->ordered_root));
 245		list_add_tail(&root->ordered_root, &fs_info->ordered_roots);
 246		spin_unlock(&fs_info->ordered_root_lock);
 247	}
 248	spin_unlock(&root->ordered_extent_lock);
 249
 250	/*
 251	 * We don't need the count_max_extents here, we can assume that all of
 252	 * that work has been done at higher layers, so this is truly the
 253	 * smallest the extent is going to get.
 254	 */
 255	spin_lock(&inode->lock);
 256	btrfs_mod_outstanding_extents(inode, 1);
 257	spin_unlock(&inode->lock);
 258
 259	return 0;
 260}
 261
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 262/*
 263 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted
 264 * when an ordered extent is finished.  If the list covers more than one
 265 * ordered extent, it is split across multiples.
 266 */
 267void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
 268			   struct btrfs_ordered_sum *sum)
 269{
 270	struct btrfs_ordered_inode_tree *tree;
 271
 272	tree = &BTRFS_I(entry->inode)->ordered_tree;
 273	spin_lock_irq(&tree->lock);
 274	list_add_tail(&sum->list, &entry->list);
 275	spin_unlock_irq(&tree->lock);
 276}
 277
 278static void finish_ordered_fn(struct btrfs_work *work)
 279{
 280	struct btrfs_ordered_extent *ordered_extent;
 281
 282	ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
 283	btrfs_finish_ordered_io(ordered_extent);
 284}
 285
 286/*
 287 * Mark all ordered extents io inside the specified range finished.
 288 *
 289 * @page:	 The involved page for the operation.
 290 *		 For uncompressed buffered IO, the page status also needs to be
 291 *		 updated to indicate whether the pending ordered io is finished.
 292 *		 Can be NULL for direct IO and compressed write.
 293 *		 For these cases, callers are ensured they won't execute the
 294 *		 endio function twice.
 
 
 295 *
 296 * This function is called for endio, thus the range must have ordered
 297 * extent(s) covering it.
 298 */
 299void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,
 300				    struct page *page, u64 file_offset,
 301				    u64 num_bytes, bool uptodate)
 
 302{
 303	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 304	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 305	struct btrfs_workqueue *wq;
 306	struct rb_node *node;
 307	struct btrfs_ordered_extent *entry = NULL;
 308	unsigned long flags;
 309	u64 cur = file_offset;
 310
 311	if (btrfs_is_free_space_inode(inode))
 312		wq = fs_info->endio_freespace_worker;
 313	else
 314		wq = fs_info->endio_write_workers;
 315
 316	if (page)
 317		ASSERT(page->mapping && page_offset(page) <= file_offset &&
 318		       file_offset + num_bytes <= page_offset(page) + PAGE_SIZE);
 319
 320	spin_lock_irqsave(&tree->lock, flags);
 321	while (cur < file_offset + num_bytes) {
 322		u64 entry_end;
 323		u64 end;
 324		u32 len;
 325
 326		node = tree_search(tree, cur);
 327		/* No ordered extents at all */
 328		if (!node)
 329			break;
 330
 331		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 332		entry_end = entry->file_offset + entry->num_bytes;
 333		/*
 334		 * |<-- OE --->|  |
 335		 *		  cur
 336		 * Go to next OE.
 337		 */
 338		if (cur >= entry_end) {
 339			node = rb_next(node);
 340			/* No more ordered extents, exit */
 341			if (!node)
 342				break;
 343			entry = rb_entry(node, struct btrfs_ordered_extent,
 344					 rb_node);
 345
 346			/* Go to next ordered extent and continue */
 347			cur = entry->file_offset;
 348			continue;
 349		}
 350		/*
 351		 * |	|<--- OE --->|
 352		 * cur
 353		 * Go to the start of OE.
 354		 */
 355		if (cur < entry->file_offset) {
 356			cur = entry->file_offset;
 357			continue;
 358		}
 359
 360		/*
 361		 * Now we are definitely inside one ordered extent.
 362		 *
 363		 * |<--- OE --->|
 364		 *	|
 365		 *	cur
 366		 */
 367		end = min(entry->file_offset + entry->num_bytes,
 368			  file_offset + num_bytes) - 1;
 369		ASSERT(end + 1 - cur < U32_MAX);
 370		len = end + 1 - cur;
 371
 372		if (page) {
 373			/*
 374			 * Ordered (Private2) bit indicates whether we still
 375			 * have pending io unfinished for the ordered extent.
 376			 *
 377			 * If there's no such bit, we need to skip to next range.
 378			 */
 379			if (!btrfs_page_test_ordered(fs_info, page, cur, len)) {
 380				cur += len;
 381				continue;
 382			}
 383			btrfs_page_clear_ordered(fs_info, page, cur, len);
 384		}
 385
 386		/* Now we're fine to update the accounting */
 387		if (unlikely(len > entry->bytes_left)) {
 388			WARN_ON(1);
 389			btrfs_crit(fs_info,
 390"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%u left=%llu",
 391				   inode->root->root_key.objectid,
 392				   btrfs_ino(inode),
 393				   entry->file_offset,
 394				   entry->num_bytes,
 395				   len, entry->bytes_left);
 396			entry->bytes_left = 0;
 397		} else {
 398			entry->bytes_left -= len;
 399		}
 400
 401		if (!uptodate)
 402			set_bit(BTRFS_ORDERED_IOERR, &entry->flags);
 403
 404		/*
 405		 * All the IO of the ordered extent is finished, we need to queue
 406		 * the finish_func to be executed.
 407		 */
 408		if (entry->bytes_left == 0) {
 409			set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 410			cond_wake_up(&entry->wait);
 411			refcount_inc(&entry->refs);
 412			trace_btrfs_ordered_extent_mark_finished(inode, entry);
 413			spin_unlock_irqrestore(&tree->lock, flags);
 414			btrfs_init_work(&entry->work, finish_ordered_fn, NULL, NULL);
 415			btrfs_queue_work(wq, &entry->work);
 416			spin_lock_irqsave(&tree->lock, flags);
 417		}
 418		cur += len;
 419	}
 420	spin_unlock_irqrestore(&tree->lock, flags);
 421}
 422
 423/*
 424 * Finish IO for one ordered extent across a given range.  The range can only
 425 * contain one ordered extent.
 426 *
 427 * @cached:	 The cached ordered extent. If not NULL, we can skip the tree
 428 *               search and use the ordered extent directly.
 429 * 		 Will be also used to store the finished ordered extent.
 430 * @file_offset: File offset for the finished IO
 431 * @io_size:	 Length of the finish IO range
 
 432 *
 433 * Return true if the ordered extent is finished in the range, and update
 434 * @cached.
 435 * Return false otherwise.
 436 *
 437 * NOTE: The range can NOT cross multiple ordered extents.
 438 * Thus caller should ensure the range doesn't cross ordered extents.
 439 */
 440bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
 441				    struct btrfs_ordered_extent **cached,
 442				    u64 file_offset, u64 io_size)
 443{
 444	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 445	struct rb_node *node;
 446	struct btrfs_ordered_extent *entry = NULL;
 447	unsigned long flags;
 448	bool finished = false;
 449
 450	spin_lock_irqsave(&tree->lock, flags);
 451	if (cached && *cached) {
 452		entry = *cached;
 453		goto have_entry;
 454	}
 455
 456	node = tree_search(tree, file_offset);
 457	if (!node)
 458		goto out;
 459
 460	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 461have_entry:
 462	if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 463		goto out;
 464
 465	if (io_size > entry->bytes_left)
 466		btrfs_crit(inode->root->fs_info,
 467			   "bad ordered accounting left %llu size %llu",
 468		       entry->bytes_left, io_size);
 469
 470	entry->bytes_left -= io_size;
 
 
 471
 472	if (entry->bytes_left == 0) {
 473		/*
 474		 * Ensure only one caller can set the flag and finished_ret
 475		 * accordingly
 476		 */
 477		finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
 478		/* test_and_set_bit implies a barrier */
 479		cond_wake_up_nomb(&entry->wait);
 480	}
 481out:
 482	if (finished && cached && entry) {
 483		*cached = entry;
 484		refcount_inc(&entry->refs);
 485		trace_btrfs_ordered_extent_dec_test_pending(inode, entry);
 486	}
 487	spin_unlock_irqrestore(&tree->lock, flags);
 488	return finished;
 489}
 490
 491/*
 492 * used to drop a reference on an ordered extent.  This will free
 493 * the extent if the last reference is dropped
 494 */
 495void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 496{
 497	struct list_head *cur;
 498	struct btrfs_ordered_sum *sum;
 499
 500	trace_btrfs_ordered_extent_put(BTRFS_I(entry->inode), entry);
 501
 502	if (refcount_dec_and_test(&entry->refs)) {
 503		ASSERT(list_empty(&entry->root_extent_list));
 504		ASSERT(list_empty(&entry->log_list));
 505		ASSERT(RB_EMPTY_NODE(&entry->rb_node));
 506		if (entry->inode)
 507			btrfs_add_delayed_iput(BTRFS_I(entry->inode));
 508		while (!list_empty(&entry->list)) {
 509			cur = entry->list.next;
 510			sum = list_entry(cur, struct btrfs_ordered_sum, list);
 511			list_del(&sum->list);
 512			kvfree(sum);
 513		}
 514		kmem_cache_free(btrfs_ordered_extent_cache, entry);
 515	}
 516}
 517
 518/*
 519 * remove an ordered extent from the tree.  No references are dropped
 520 * and waiters are woken up.
 521 */
 522void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
 523				 struct btrfs_ordered_extent *entry)
 524{
 525	struct btrfs_ordered_inode_tree *tree;
 526	struct btrfs_root *root = btrfs_inode->root;
 527	struct btrfs_fs_info *fs_info = root->fs_info;
 528	struct rb_node *node;
 529	bool pending;
 530	bool freespace_inode;
 531
 532	/*
 533	 * If this is a free space inode the thread has not acquired the ordered
 534	 * extents lockdep map.
 535	 */
 536	freespace_inode = btrfs_is_free_space_inode(btrfs_inode);
 537
 538	btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);
 539	/* This is paired with btrfs_add_ordered_extent. */
 540	spin_lock(&btrfs_inode->lock);
 541	btrfs_mod_outstanding_extents(btrfs_inode, -1);
 542	spin_unlock(&btrfs_inode->lock);
 543	if (root != fs_info->tree_root) {
 544		u64 release;
 545
 546		if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))
 547			release = entry->disk_num_bytes;
 548		else
 549			release = entry->num_bytes;
 550		btrfs_delalloc_release_metadata(btrfs_inode, release, false);
 551	}
 552
 553	percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
 554				 fs_info->delalloc_batch);
 555
 556	tree = &btrfs_inode->ordered_tree;
 557	spin_lock_irq(&tree->lock);
 558	node = &entry->rb_node;
 559	rb_erase(node, &tree->tree);
 560	RB_CLEAR_NODE(node);
 561	if (tree->last == node)
 562		tree->last = NULL;
 563	set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
 564	pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);
 565	spin_unlock_irq(&tree->lock);
 566
 567	/*
 568	 * The current running transaction is waiting on us, we need to let it
 569	 * know that we're complete and wake it up.
 570	 */
 571	if (pending) {
 572		struct btrfs_transaction *trans;
 573
 574		/*
 575		 * The checks for trans are just a formality, it should be set,
 576		 * but if it isn't we don't want to deref/assert under the spin
 577		 * lock, so be nice and check if trans is set, but ASSERT() so
 578		 * if it isn't set a developer will notice.
 579		 */
 580		spin_lock(&fs_info->trans_lock);
 581		trans = fs_info->running_transaction;
 582		if (trans)
 583			refcount_inc(&trans->use_count);
 584		spin_unlock(&fs_info->trans_lock);
 585
 586		ASSERT(trans);
 587		if (trans) {
 588			if (atomic_dec_and_test(&trans->pending_ordered))
 589				wake_up(&trans->pending_wait);
 590			btrfs_put_transaction(trans);
 591		}
 592	}
 593
 594	btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);
 595
 596	spin_lock(&root->ordered_extent_lock);
 597	list_del_init(&entry->root_extent_list);
 598	root->nr_ordered_extents--;
 599
 600	trace_btrfs_ordered_extent_remove(btrfs_inode, entry);
 601
 602	if (!root->nr_ordered_extents) {
 603		spin_lock(&fs_info->ordered_root_lock);
 604		BUG_ON(list_empty(&root->ordered_root));
 605		list_del_init(&root->ordered_root);
 606		spin_unlock(&fs_info->ordered_root_lock);
 607	}
 608	spin_unlock(&root->ordered_extent_lock);
 609	wake_up(&entry->wait);
 610	if (!freespace_inode)
 611		btrfs_lockdep_release(fs_info, btrfs_ordered_extent);
 612}
 613
 614static void btrfs_run_ordered_extent_work(struct btrfs_work *work)
 615{
 616	struct btrfs_ordered_extent *ordered;
 617
 618	ordered = container_of(work, struct btrfs_ordered_extent, flush_work);
 619	btrfs_start_ordered_extent(ordered, 1);
 620	complete(&ordered->completion);
 621}
 622
 623/*
 624 * wait for all the ordered extents in a root.  This is done when balancing
 625 * space between drives.
 626 */
 627u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,
 628			       const u64 range_start, const u64 range_len)
 629{
 630	struct btrfs_fs_info *fs_info = root->fs_info;
 631	LIST_HEAD(splice);
 632	LIST_HEAD(skipped);
 633	LIST_HEAD(works);
 634	struct btrfs_ordered_extent *ordered, *next;
 635	u64 count = 0;
 636	const u64 range_end = range_start + range_len;
 637
 638	mutex_lock(&root->ordered_extent_mutex);
 639	spin_lock(&root->ordered_extent_lock);
 640	list_splice_init(&root->ordered_extents, &splice);
 641	while (!list_empty(&splice) && nr) {
 642		ordered = list_first_entry(&splice, struct btrfs_ordered_extent,
 643					   root_extent_list);
 644
 645		if (range_end <= ordered->disk_bytenr ||
 646		    ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {
 647			list_move_tail(&ordered->root_extent_list, &skipped);
 648			cond_resched_lock(&root->ordered_extent_lock);
 649			continue;
 650		}
 651
 652		list_move_tail(&ordered->root_extent_list,
 653			       &root->ordered_extents);
 654		refcount_inc(&ordered->refs);
 655		spin_unlock(&root->ordered_extent_lock);
 656
 657		btrfs_init_work(&ordered->flush_work,
 658				btrfs_run_ordered_extent_work, NULL, NULL);
 659		list_add_tail(&ordered->work_list, &works);
 660		btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);
 661
 662		cond_resched();
 663		spin_lock(&root->ordered_extent_lock);
 664		if (nr != U64_MAX)
 665			nr--;
 666		count++;
 667	}
 668	list_splice_tail(&skipped, &root->ordered_extents);
 669	list_splice_tail(&splice, &root->ordered_extents);
 670	spin_unlock(&root->ordered_extent_lock);
 671
 672	list_for_each_entry_safe(ordered, next, &works, work_list) {
 673		list_del_init(&ordered->work_list);
 674		wait_for_completion(&ordered->completion);
 675		btrfs_put_ordered_extent(ordered);
 676		cond_resched();
 677	}
 678	mutex_unlock(&root->ordered_extent_mutex);
 679
 680	return count;
 681}
 682
 683void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 684			     const u64 range_start, const u64 range_len)
 685{
 686	struct btrfs_root *root;
 687	struct list_head splice;
 688	u64 done;
 689
 690	INIT_LIST_HEAD(&splice);
 691
 692	mutex_lock(&fs_info->ordered_operations_mutex);
 693	spin_lock(&fs_info->ordered_root_lock);
 694	list_splice_init(&fs_info->ordered_roots, &splice);
 695	while (!list_empty(&splice) && nr) {
 696		root = list_first_entry(&splice, struct btrfs_root,
 697					ordered_root);
 698		root = btrfs_grab_root(root);
 699		BUG_ON(!root);
 700		list_move_tail(&root->ordered_root,
 701			       &fs_info->ordered_roots);
 702		spin_unlock(&fs_info->ordered_root_lock);
 703
 704		done = btrfs_wait_ordered_extents(root, nr,
 705						  range_start, range_len);
 706		btrfs_put_root(root);
 707
 708		spin_lock(&fs_info->ordered_root_lock);
 709		if (nr != U64_MAX) {
 710			nr -= done;
 711		}
 712	}
 713	list_splice_tail(&splice, &fs_info->ordered_roots);
 714	spin_unlock(&fs_info->ordered_root_lock);
 715	mutex_unlock(&fs_info->ordered_operations_mutex);
 716}
 717
 718/*
 719 * Used to start IO or wait for a given ordered extent to finish.
 720 *
 721 * If wait is one, this effectively waits on page writeback for all the pages
 722 * in the extent, and it waits on the io completion code to insert
 723 * metadata into the btree corresponding to the extent
 724 */
 725void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry, int wait)
 726{
 727	u64 start = entry->file_offset;
 728	u64 end = start + entry->num_bytes - 1;
 729	struct btrfs_inode *inode = BTRFS_I(entry->inode);
 730	bool freespace_inode;
 731
 732	trace_btrfs_ordered_extent_start(inode, entry);
 733
 734	/*
 735	 * If this is a free space inode do not take the ordered extents lockdep
 736	 * map.
 737	 */
 738	freespace_inode = btrfs_is_free_space_inode(inode);
 739
 740	/*
 741	 * pages in the range can be dirty, clean or writeback.  We
 742	 * start IO on any dirty ones so the wait doesn't stall waiting
 743	 * for the flusher thread to find them
 744	 */
 745	if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
 746		filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);
 747	if (wait) {
 748		if (!freespace_inode)
 749			btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);
 750		wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
 751						 &entry->flags));
 752	}
 753}
 754
 755/*
 756 * Used to wait on ordered extents across a large range of bytes.
 757 */
 758int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 759{
 760	int ret = 0;
 761	int ret_wb = 0;
 762	u64 end;
 763	u64 orig_end;
 764	struct btrfs_ordered_extent *ordered;
 765
 766	if (start + len < start) {
 767		orig_end = OFFSET_MAX;
 768	} else {
 769		orig_end = start + len - 1;
 770		if (orig_end > OFFSET_MAX)
 771			orig_end = OFFSET_MAX;
 772	}
 773
 774	/* start IO across the range first to instantiate any delalloc
 775	 * extents
 776	 */
 777	ret = btrfs_fdatawrite_range(inode, start, orig_end);
 778	if (ret)
 779		return ret;
 780
 781	/*
 782	 * If we have a writeback error don't return immediately. Wait first
 783	 * for any ordered extents that haven't completed yet. This is to make
 784	 * sure no one can dirty the same page ranges and call writepages()
 785	 * before the ordered extents complete - to avoid failures (-EEXIST)
 786	 * when adding the new ordered extents to the ordered tree.
 787	 */
 788	ret_wb = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 789
 790	end = orig_end;
 791	while (1) {
 792		ordered = btrfs_lookup_first_ordered_extent(BTRFS_I(inode), end);
 793		if (!ordered)
 794			break;
 795		if (ordered->file_offset > orig_end) {
 796			btrfs_put_ordered_extent(ordered);
 797			break;
 798		}
 799		if (ordered->file_offset + ordered->num_bytes <= start) {
 800			btrfs_put_ordered_extent(ordered);
 801			break;
 802		}
 803		btrfs_start_ordered_extent(ordered, 1);
 804		end = ordered->file_offset;
 805		/*
 806		 * If the ordered extent had an error save the error but don't
 807		 * exit without waiting first for all other ordered extents in
 808		 * the range to complete.
 809		 */
 810		if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
 811			ret = -EIO;
 812		btrfs_put_ordered_extent(ordered);
 813		if (end == 0 || end == start)
 814			break;
 815		end--;
 816	}
 817	return ret_wb ? ret_wb : ret;
 818}
 819
 820/*
 821 * find an ordered extent corresponding to file_offset.  return NULL if
 822 * nothing is found, otherwise take a reference on the extent and return it
 823 */
 824struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
 825							 u64 file_offset)
 826{
 827	struct btrfs_ordered_inode_tree *tree;
 828	struct rb_node *node;
 829	struct btrfs_ordered_extent *entry = NULL;
 830	unsigned long flags;
 831
 832	tree = &inode->ordered_tree;
 833	spin_lock_irqsave(&tree->lock, flags);
 834	node = tree_search(tree, file_offset);
 835	if (!node)
 836		goto out;
 837
 838	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 839	if (!in_range(file_offset, entry->file_offset, entry->num_bytes))
 840		entry = NULL;
 841	if (entry) {
 842		refcount_inc(&entry->refs);
 843		trace_btrfs_ordered_extent_lookup(inode, entry);
 844	}
 845out:
 846	spin_unlock_irqrestore(&tree->lock, flags);
 847	return entry;
 848}
 849
 850/* Since the DIO code tries to lock a wide area we need to look for any ordered
 851 * extents that exist in the range, rather than just the start of the range.
 852 */
 853struct btrfs_ordered_extent *btrfs_lookup_ordered_range(
 854		struct btrfs_inode *inode, u64 file_offset, u64 len)
 855{
 856	struct btrfs_ordered_inode_tree *tree;
 857	struct rb_node *node;
 858	struct btrfs_ordered_extent *entry = NULL;
 859
 860	tree = &inode->ordered_tree;
 861	spin_lock_irq(&tree->lock);
 862	node = tree_search(tree, file_offset);
 863	if (!node) {
 864		node = tree_search(tree, file_offset + len);
 865		if (!node)
 866			goto out;
 867	}
 868
 869	while (1) {
 870		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 871		if (range_overlaps(entry, file_offset, len))
 872			break;
 873
 874		if (entry->file_offset >= file_offset + len) {
 875			entry = NULL;
 876			break;
 877		}
 878		entry = NULL;
 879		node = rb_next(node);
 880		if (!node)
 881			break;
 882	}
 883out:
 884	if (entry) {
 885		refcount_inc(&entry->refs);
 886		trace_btrfs_ordered_extent_lookup_range(inode, entry);
 887	}
 888	spin_unlock_irq(&tree->lock);
 889	return entry;
 890}
 891
 892/*
 893 * Adds all ordered extents to the given list. The list ends up sorted by the
 894 * file_offset of the ordered extents.
 895 */
 896void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,
 897					   struct list_head *list)
 898{
 899	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 900	struct rb_node *n;
 901
 902	ASSERT(inode_is_locked(&inode->vfs_inode));
 903
 904	spin_lock_irq(&tree->lock);
 905	for (n = rb_first(&tree->tree); n; n = rb_next(n)) {
 906		struct btrfs_ordered_extent *ordered;
 907
 908		ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);
 909
 910		if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))
 911			continue;
 912
 913		ASSERT(list_empty(&ordered->log_list));
 914		list_add_tail(&ordered->log_list, list);
 915		refcount_inc(&ordered->refs);
 916		trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);
 917	}
 918	spin_unlock_irq(&tree->lock);
 919}
 920
 921/*
 922 * lookup and return any extent before 'file_offset'.  NULL is returned
 923 * if none is found
 924 */
 925struct btrfs_ordered_extent *
 926btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)
 927{
 928	struct btrfs_ordered_inode_tree *tree;
 929	struct rb_node *node;
 930	struct btrfs_ordered_extent *entry = NULL;
 931
 932	tree = &inode->ordered_tree;
 933	spin_lock_irq(&tree->lock);
 934	node = tree_search(tree, file_offset);
 935	if (!node)
 936		goto out;
 937
 938	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 939	refcount_inc(&entry->refs);
 940	trace_btrfs_ordered_extent_lookup_first(inode, entry);
 941out:
 942	spin_unlock_irq(&tree->lock);
 943	return entry;
 944}
 945
 946/*
 947 * Lookup the first ordered extent that overlaps the range
 948 * [@file_offset, @file_offset + @len).
 949 *
 950 * The difference between this and btrfs_lookup_first_ordered_extent() is
 951 * that this one won't return any ordered extent that does not overlap the range.
 952 * And the difference against btrfs_lookup_ordered_extent() is, this function
 953 * ensures the first ordered extent gets returned.
 954 */
 955struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(
 956			struct btrfs_inode *inode, u64 file_offset, u64 len)
 957{
 958	struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
 959	struct rb_node *node;
 960	struct rb_node *cur;
 961	struct rb_node *prev;
 962	struct rb_node *next;
 963	struct btrfs_ordered_extent *entry = NULL;
 964
 965	spin_lock_irq(&tree->lock);
 966	node = tree->tree.rb_node;
 967	/*
 968	 * Here we don't want to use tree_search() which will use tree->last
 969	 * and screw up the search order.
 970	 * And __tree_search() can't return the adjacent ordered extents
 971	 * either, thus here we do our own search.
 972	 */
 973	while (node) {
 974		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);
 975
 976		if (file_offset < entry->file_offset) {
 977			node = node->rb_left;
 978		} else if (file_offset >= entry_end(entry)) {
 979			node = node->rb_right;
 980		} else {
 981			/*
 982			 * Direct hit, got an ordered extent that starts at
 983			 * @file_offset
 984			 */
 985			goto out;
 986		}
 987	}
 988	if (!entry) {
 989		/* Empty tree */
 990		goto out;
 991	}
 992
 993	cur = &entry->rb_node;
 994	/* We got an entry around @file_offset, check adjacent entries */
 995	if (entry->file_offset < file_offset) {
 996		prev = cur;
 997		next = rb_next(cur);
 998	} else {
 999		prev = rb_prev(cur);
1000		next = cur;
1001	}
1002	if (prev) {
1003		entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);
1004		if (range_overlaps(entry, file_offset, len))
1005			goto out;
1006	}
1007	if (next) {
1008		entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);
1009		if (range_overlaps(entry, file_offset, len))
1010			goto out;
1011	}
1012	/* No ordered extent in the range */
1013	entry = NULL;
1014out:
1015	if (entry) {
1016		refcount_inc(&entry->refs);
1017		trace_btrfs_ordered_extent_lookup_first_range(inode, entry);
1018	}
1019
1020	spin_unlock_irq(&tree->lock);
1021	return entry;
1022}
1023
1024/*
1025 * Lock the passed range and ensures all pending ordered extents in it are run
1026 * to completion.
1027 *
1028 * @inode:        Inode whose ordered tree is to be searched
1029 * @start:        Beginning of range to flush
1030 * @end:          Last byte of range to lock
1031 * @cached_state: If passed, will return the extent state responsible for the
1032 *                locked range. It's the caller's responsibility to free the
1033 *                cached state.
1034 *
1035 * Always return with the given range locked, ensuring after it's called no
1036 * order extent can be pending.
1037 */
1038void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
1039					u64 end,
1040					struct extent_state **cached_state)
1041{
1042	struct btrfs_ordered_extent *ordered;
1043	struct extent_state *cache = NULL;
1044	struct extent_state **cachedp = &cache;
1045
1046	if (cached_state)
1047		cachedp = cached_state;
1048
1049	while (1) {
1050		lock_extent(&inode->io_tree, start, end, cachedp);
1051		ordered = btrfs_lookup_ordered_range(inode, start,
1052						     end - start + 1);
1053		if (!ordered) {
1054			/*
1055			 * If no external cached_state has been passed then
1056			 * decrement the extra ref taken for cachedp since we
1057			 * aren't exposing it outside of this function
1058			 */
1059			if (!cached_state)
1060				refcount_dec(&cache->refs);
1061			break;
1062		}
1063		unlock_extent(&inode->io_tree, start, end, cachedp);
1064		btrfs_start_ordered_extent(ordered, 1);
1065		btrfs_put_ordered_extent(ordered);
1066	}
1067}
1068
1069/*
1070 * Lock the passed range and ensure all pending ordered extents in it are run
1071 * to completion in nowait mode.
1072 *
1073 * Return true if btrfs_lock_ordered_range does not return any extents,
1074 * otherwise false.
1075 */
1076bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,
1077				  struct extent_state **cached_state)
1078{
1079	struct btrfs_ordered_extent *ordered;
1080
1081	if (!try_lock_extent(&inode->io_tree, start, end, cached_state))
1082		return false;
1083
1084	ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1);
1085	if (!ordered)
1086		return true;
1087
1088	btrfs_put_ordered_extent(ordered);
1089	unlock_extent(&inode->io_tree, start, end, cached_state);
1090
1091	return false;
1092}
1093
1094
1095static int clone_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pos,
1096				u64 len)
1097{
1098	struct inode *inode = ordered->inode;
1099	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1100	u64 file_offset = ordered->file_offset + pos;
1101	u64 disk_bytenr = ordered->disk_bytenr + pos;
1102	unsigned long flags = ordered->flags & BTRFS_ORDERED_TYPE_FLAGS;
 
 
 
 
 
 
 
 
 
 
 
 
 
1103
1104	/*
1105	 * The splitting extent is already counted and will be added again in
1106	 * btrfs_add_ordered_extent_*(). Subtract len to avoid double counting.
 
1107	 */
1108	percpu_counter_add_batch(&fs_info->ordered_bytes, -len,
1109				 fs_info->delalloc_batch);
1110	WARN_ON_ONCE(flags & (1 << BTRFS_ORDERED_COMPRESSED));
1111	return btrfs_add_ordered_extent(BTRFS_I(inode), file_offset, len, len,
1112					disk_bytenr, len, 0, flags,
1113					ordered->compress_type);
 
 
 
 
 
 
 
 
 
 
1114}
1115
1116int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre,
1117				u64 post)
1118{
1119	struct inode *inode = ordered->inode;
1120	struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
1121	struct rb_node *node;
1122	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1123	int ret = 0;
1124
1125	trace_btrfs_ordered_extent_split(BTRFS_I(inode), ordered);
1126
1127	spin_lock_irq(&tree->lock);
1128	/* Remove from tree once */
1129	node = &ordered->rb_node;
1130	rb_erase(node, &tree->tree);
1131	RB_CLEAR_NODE(node);
1132	if (tree->last == node)
1133		tree->last = NULL;
1134
1135	ordered->file_offset += pre;
1136	ordered->disk_bytenr += pre;
1137	ordered->num_bytes -= (pre + post);
1138	ordered->disk_num_bytes -= (pre + post);
1139	ordered->bytes_left -= (pre + post);
1140
1141	/* Re-insert the node */
1142	node = tree_insert(&tree->tree, ordered->file_offset, &ordered->rb_node);
1143	if (node)
1144		btrfs_panic(fs_info, -EEXIST,
1145			"zoned: inconsistency in ordered tree at offset %llu",
1146			    ordered->file_offset);
1147
1148	spin_unlock_irq(&tree->lock);
1149
1150	if (pre)
1151		ret = clone_ordered_extent(ordered, 0, pre);
1152	if (ret == 0 && post)
1153		ret = clone_ordered_extent(ordered, pre + ordered->disk_num_bytes,
1154					   post);
1155
1156	return ret;
1157}
1158
1159int __init ordered_data_init(void)
1160{
1161	btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
1162				     sizeof(struct btrfs_ordered_extent), 0,
1163				     SLAB_MEM_SPREAD,
1164				     NULL);
1165	if (!btrfs_ordered_extent_cache)
1166		return -ENOMEM;
1167
1168	return 0;
1169}
1170
1171void __cold ordered_data_exit(void)
1172{
1173	kmem_cache_destroy(btrfs_ordered_extent_cache);
1174}
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}