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1// SPDX-License-Identifier: GPL-2.02/*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 "block-group.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 find34 * in the tree35 */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		else52			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 the62 * first lesser offset63 */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		else83			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, otherwise125 * the first one less than this offset126 */127static inline struct rb_node *ordered_tree_search(struct btrfs_inode *inode,128						  u64 file_offset)129{130	struct rb_node *prev = NULL;131	struct rb_node *ret;132	struct btrfs_ordered_extent *entry;133 134	if (inode->ordered_tree_last) {135		entry = rb_entry(inode->ordered_tree_last, struct btrfs_ordered_extent,136				 rb_node);137		if (in_range(file_offset, entry->file_offset, entry->num_bytes))138			return inode->ordered_tree_last;139	}140	ret = __tree_search(&inode->ordered_tree, file_offset, &prev);141	if (!ret)142		ret = prev;143	if (ret)144		inode->ordered_tree_last = ret;145	return ret;146}147 148static struct btrfs_ordered_extent *alloc_ordered_extent(149			struct btrfs_inode *inode, u64 file_offset, u64 num_bytes,150			u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,151			u64 offset, unsigned long flags, int compress_type)152{153	struct btrfs_ordered_extent *entry;154	int ret;155	u64 qgroup_rsv = 0;156 157	if (flags &158	    ((1 << BTRFS_ORDERED_NOCOW) | (1 << BTRFS_ORDERED_PREALLOC))) {159		/* For nocow write, we can release the qgroup rsv right now */160		ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes, &qgroup_rsv);161		if (ret < 0)162			return ERR_PTR(ret);163	} else {164		/*165		 * The ordered extent has reserved qgroup space, release now166		 * and pass the reserved number for qgroup_record to free.167		 */168		ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes, &qgroup_rsv);169		if (ret < 0)170			return ERR_PTR(ret);171	}172	entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);173	if (!entry)174		return ERR_PTR(-ENOMEM);175 176	entry->file_offset = file_offset;177	entry->num_bytes = num_bytes;178	entry->ram_bytes = ram_bytes;179	entry->disk_bytenr = disk_bytenr;180	entry->disk_num_bytes = disk_num_bytes;181	entry->offset = offset;182	entry->bytes_left = num_bytes;183	entry->inode = BTRFS_I(igrab(&inode->vfs_inode));184	entry->compress_type = compress_type;185	entry->truncated_len = (u64)-1;186	entry->qgroup_rsv = qgroup_rsv;187	entry->flags = flags;188	refcount_set(&entry->refs, 1);189	init_waitqueue_head(&entry->wait);190	INIT_LIST_HEAD(&entry->list);191	INIT_LIST_HEAD(&entry->log_list);192	INIT_LIST_HEAD(&entry->root_extent_list);193	INIT_LIST_HEAD(&entry->work_list);194	INIT_LIST_HEAD(&entry->bioc_list);195	init_completion(&entry->completion);196 197	/*198	 * We don't need the count_max_extents here, we can assume that all of199	 * that work has been done at higher layers, so this is truly the200	 * smallest the extent is going to get.201	 */202	spin_lock(&inode->lock);203	btrfs_mod_outstanding_extents(inode, 1);204	spin_unlock(&inode->lock);205 206	return entry;207}208 209static void insert_ordered_extent(struct btrfs_ordered_extent *entry)210{211	struct btrfs_inode *inode = entry->inode;212	struct btrfs_root *root = inode->root;213	struct btrfs_fs_info *fs_info = root->fs_info;214	struct rb_node *node;215 216	trace_btrfs_ordered_extent_add(inode, entry);217 218	percpu_counter_add_batch(&fs_info->ordered_bytes, entry->num_bytes,219				 fs_info->delalloc_batch);220 221	/* One ref for the tree. */222	refcount_inc(&entry->refs);223 224	spin_lock_irq(&inode->ordered_tree_lock);225	node = tree_insert(&inode->ordered_tree, entry->file_offset,226			   &entry->rb_node);227	if (unlikely(node))228		btrfs_panic(fs_info, -EEXIST,229				"inconsistency in ordered tree at offset %llu",230				entry->file_offset);231	spin_unlock_irq(&inode->ordered_tree_lock);232 233	spin_lock(&root->ordered_extent_lock);234	list_add_tail(&entry->root_extent_list,235		      &root->ordered_extents);236	root->nr_ordered_extents++;237	if (root->nr_ordered_extents == 1) {238		spin_lock(&fs_info->ordered_root_lock);239		BUG_ON(!list_empty(&root->ordered_root));240		list_add_tail(&root->ordered_root, &fs_info->ordered_roots);241		spin_unlock(&fs_info->ordered_root_lock);242	}243	spin_unlock(&root->ordered_extent_lock);244}245 246/*247 * Add an ordered extent to the per-inode tree.248 *249 * @inode:           Inode that this extent is for.250 * @file_offset:     Logical offset in file where the extent starts.251 * @num_bytes:       Logical length of extent in file.252 * @ram_bytes:       Full length of unencoded data.253 * @disk_bytenr:     Offset of extent on disk.254 * @disk_num_bytes:  Size of extent on disk.255 * @offset:          Offset into unencoded data where file data starts.256 * @flags:           Flags specifying type of extent (1 << BTRFS_ORDERED_*).257 * @compress_type:   Compression algorithm used for data.258 *259 * Most of these parameters correspond to &struct btrfs_file_extent_item. The260 * tree is given a single reference on the ordered extent that was inserted, and261 * the returned pointer is given a second reference.262 *263 * Return: the new ordered extent or error pointer.264 */265struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(266			struct btrfs_inode *inode, u64 file_offset,267			const struct btrfs_file_extent *file_extent, unsigned long flags)268{269	struct btrfs_ordered_extent *entry;270 271	ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);272 273	/*274	 * For regular writes, we just use the members in @file_extent.275	 *276	 * For NOCOW, we don't really care about the numbers except @start and277	 * file_extent->num_bytes, as we won't insert a file extent item at all.278	 *279	 * For PREALLOC, we do not use ordered extent members, but280	 * btrfs_mark_extent_written() handles everything.281	 *282	 * So here we always pass 0 as offset for NOCOW/PREALLOC ordered extents,283	 * or btrfs_split_ordered_extent() cannot handle it correctly.284	 */285	if (flags & ((1U << BTRFS_ORDERED_NOCOW) | (1U << BTRFS_ORDERED_PREALLOC)))286		entry = alloc_ordered_extent(inode, file_offset,287					     file_extent->num_bytes,288					     file_extent->num_bytes,289					     file_extent->disk_bytenr + file_extent->offset,290					     file_extent->num_bytes, 0, flags,291					     file_extent->compression);292	else293		entry = alloc_ordered_extent(inode, file_offset,294					     file_extent->num_bytes,295					     file_extent->ram_bytes,296					     file_extent->disk_bytenr,297					     file_extent->disk_num_bytes,298					     file_extent->offset, flags,299					     file_extent->compression);300	if (!IS_ERR(entry))301		insert_ordered_extent(entry);302	return entry;303}304 305/*306 * Add a struct btrfs_ordered_sum into the list of checksums to be inserted307 * when an ordered extent is finished.  If the list covers more than one308 * ordered extent, it is split across multiples.309 */310void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,311			   struct btrfs_ordered_sum *sum)312{313	struct btrfs_inode *inode = entry->inode;314 315	spin_lock_irq(&inode->ordered_tree_lock);316	list_add_tail(&sum->list, &entry->list);317	spin_unlock_irq(&inode->ordered_tree_lock);318}319 320void btrfs_mark_ordered_extent_error(struct btrfs_ordered_extent *ordered)321{322	if (!test_and_set_bit(BTRFS_ORDERED_IOERR, &ordered->flags))323		mapping_set_error(ordered->inode->vfs_inode.i_mapping, -EIO);324}325 326static void finish_ordered_fn(struct btrfs_work *work)327{328	struct btrfs_ordered_extent *ordered_extent;329 330	ordered_extent = container_of(work, struct btrfs_ordered_extent, work);331	btrfs_finish_ordered_io(ordered_extent);332}333 334static bool can_finish_ordered_extent(struct btrfs_ordered_extent *ordered,335				      struct folio *folio, u64 file_offset,336				      u64 len, bool uptodate)337{338	struct btrfs_inode *inode = ordered->inode;339	struct btrfs_fs_info *fs_info = inode->root->fs_info;340 341	lockdep_assert_held(&inode->ordered_tree_lock);342 343	if (folio) {344		ASSERT(folio->mapping);345		ASSERT(folio_pos(folio) <= file_offset);346		ASSERT(file_offset + len <= folio_pos(folio) + folio_size(folio));347 348		/*349		 * Ordered (Private2) bit indicates whether we still have350		 * pending io unfinished for the ordered extent.351		 *352		 * If there's no such bit, we need to skip to next range.353		 */354		if (!btrfs_folio_test_ordered(fs_info, folio, file_offset, len))355			return false;356		btrfs_folio_clear_ordered(fs_info, folio, file_offset, len);357	}358 359	/* Now we're fine to update the accounting. */360	if (WARN_ON_ONCE(len > ordered->bytes_left)) {361		btrfs_crit(fs_info,362"bad ordered extent accounting, root=%llu ino=%llu OE offset=%llu OE len=%llu to_dec=%llu left=%llu",363			   btrfs_root_id(inode->root), btrfs_ino(inode),364			   ordered->file_offset, ordered->num_bytes,365			   len, ordered->bytes_left);366		ordered->bytes_left = 0;367	} else {368		ordered->bytes_left -= len;369	}370 371	if (!uptodate)372		set_bit(BTRFS_ORDERED_IOERR, &ordered->flags);373 374	if (ordered->bytes_left)375		return false;376 377	/*378	 * All the IO of the ordered extent is finished, we need to queue379	 * the finish_func to be executed.380	 */381	set_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags);382	cond_wake_up(&ordered->wait);383	refcount_inc(&ordered->refs);384	trace_btrfs_ordered_extent_mark_finished(inode, ordered);385	return true;386}387 388static void btrfs_queue_ordered_fn(struct btrfs_ordered_extent *ordered)389{390	struct btrfs_inode *inode = ordered->inode;391	struct btrfs_fs_info *fs_info = inode->root->fs_info;392	struct btrfs_workqueue *wq = btrfs_is_free_space_inode(inode) ?393		fs_info->endio_freespace_worker : fs_info->endio_write_workers;394 395	btrfs_init_work(&ordered->work, finish_ordered_fn, NULL);396	btrfs_queue_work(wq, &ordered->work);397}398 399void btrfs_finish_ordered_extent(struct btrfs_ordered_extent *ordered,400				 struct folio *folio, u64 file_offset, u64 len,401				 bool uptodate)402{403	struct btrfs_inode *inode = ordered->inode;404	unsigned long flags;405	bool ret;406 407	trace_btrfs_finish_ordered_extent(inode, file_offset, len, uptodate);408 409	spin_lock_irqsave(&inode->ordered_tree_lock, flags);410	ret = can_finish_ordered_extent(ordered, folio, file_offset, len,411					uptodate);412	spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);413 414	/*415	 * If this is a COW write it means we created new extent maps for the416	 * range and they point to unwritten locations if we got an error either417	 * before submitting a bio or during IO.418	 *419	 * We have marked the ordered extent with BTRFS_ORDERED_IOERR, and we420	 * are queuing its completion below. During completion, at421	 * btrfs_finish_one_ordered(), we will drop the extent maps for the422	 * unwritten extents.423	 *424	 * However because completion runs in a work queue we can end up having425	 * a fast fsync running before that. In the case of direct IO, once we426	 * unlock the inode the fsync might start, and we queue the completion427	 * before unlocking the inode. In the case of buffered IO when writeback428	 * finishes (end_bbio_data_write()) we queue the completion, so if the429	 * writeback was triggered by a fast fsync, the fsync might start430	 * logging before ordered extent completion runs in the work queue.431	 *432	 * The fast fsync will log file extent items based on the extent maps it433	 * finds, so if by the time it collects extent maps the ordered extent434	 * completion didn't happen yet, it will log file extent items that435	 * point to unwritten extents, resulting in a corruption if a crash436	 * happens and the log tree is replayed. Note that a fast fsync does not437	 * wait for completion of ordered extents in order to reduce latency.438	 *439	 * Set a flag in the inode so that the next fast fsync will wait for440	 * ordered extents to complete before starting to log.441	 */442	if (!uptodate && !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))443		set_bit(BTRFS_INODE_COW_WRITE_ERROR, &inode->runtime_flags);444 445	if (ret)446		btrfs_queue_ordered_fn(ordered);447}448 449/*450 * Mark all ordered extents io inside the specified range finished.451 *452 * @folio:	 The involved folio for the operation.453 *		 For uncompressed buffered IO, the folio status also needs to be454 *		 updated to indicate whether the pending ordered io is finished.455 *		 Can be NULL for direct IO and compressed write.456 *		 For these cases, callers are ensured they won't execute the457 *		 endio function twice.458 *459 * This function is called for endio, thus the range must have ordered460 * extent(s) covering it.461 */462void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode,463				    struct folio *folio, u64 file_offset,464				    u64 num_bytes, bool uptodate)465{466	struct rb_node *node;467	struct btrfs_ordered_extent *entry = NULL;468	unsigned long flags;469	u64 cur = file_offset;470 471	trace_btrfs_writepage_end_io_hook(inode, file_offset,472					  file_offset + num_bytes - 1,473					  uptodate);474 475	spin_lock_irqsave(&inode->ordered_tree_lock, flags);476	while (cur < file_offset + num_bytes) {477		u64 entry_end;478		u64 end;479		u32 len;480 481		node = ordered_tree_search(inode, cur);482		/* No ordered extents at all */483		if (!node)484			break;485 486		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);487		entry_end = entry->file_offset + entry->num_bytes;488		/*489		 * |<-- OE --->|  |490		 *		  cur491		 * Go to next OE.492		 */493		if (cur >= entry_end) {494			node = rb_next(node);495			/* No more ordered extents, exit */496			if (!node)497				break;498			entry = rb_entry(node, struct btrfs_ordered_extent,499					 rb_node);500 501			/* Go to next ordered extent and continue */502			cur = entry->file_offset;503			continue;504		}505		/*506		 * |	|<--- OE --->|507		 * cur508		 * Go to the start of OE.509		 */510		if (cur < entry->file_offset) {511			cur = entry->file_offset;512			continue;513		}514 515		/*516		 * Now we are definitely inside one ordered extent.517		 *518		 * |<--- OE --->|519		 *	|520		 *	cur521		 */522		end = min(entry->file_offset + entry->num_bytes,523			  file_offset + num_bytes) - 1;524		ASSERT(end + 1 - cur < U32_MAX);525		len = end + 1 - cur;526 527		if (can_finish_ordered_extent(entry, folio, cur, len, uptodate)) {528			spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);529			btrfs_queue_ordered_fn(entry);530			spin_lock_irqsave(&inode->ordered_tree_lock, flags);531		}532		cur += len;533	}534	spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);535}536 537/*538 * Finish IO for one ordered extent across a given range.  The range can only539 * contain one ordered extent.540 *541 * @cached:	 The cached ordered extent. If not NULL, we can skip the tree542 *               search and use the ordered extent directly.543 * 		 Will be also used to store the finished ordered extent.544 * @file_offset: File offset for the finished IO545 * @io_size:	 Length of the finish IO range546 *547 * Return true if the ordered extent is finished in the range, and update548 * @cached.549 * Return false otherwise.550 *551 * NOTE: The range can NOT cross multiple ordered extents.552 * Thus caller should ensure the range doesn't cross ordered extents.553 */554bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,555				    struct btrfs_ordered_extent **cached,556				    u64 file_offset, u64 io_size)557{558	struct rb_node *node;559	struct btrfs_ordered_extent *entry = NULL;560	unsigned long flags;561	bool finished = false;562 563	spin_lock_irqsave(&inode->ordered_tree_lock, flags);564	if (cached && *cached) {565		entry = *cached;566		goto have_entry;567	}568 569	node = ordered_tree_search(inode, file_offset);570	if (!node)571		goto out;572 573	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);574have_entry:575	if (!in_range(file_offset, entry->file_offset, entry->num_bytes))576		goto out;577 578	if (io_size > entry->bytes_left)579		btrfs_crit(inode->root->fs_info,580			   "bad ordered accounting left %llu size %llu",581		       entry->bytes_left, io_size);582 583	entry->bytes_left -= io_size;584 585	if (entry->bytes_left == 0) {586		/*587		 * Ensure only one caller can set the flag and finished_ret588		 * accordingly589		 */590		finished = !test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);591		/* test_and_set_bit implies a barrier */592		cond_wake_up_nomb(&entry->wait);593	}594out:595	if (finished && cached && entry) {596		*cached = entry;597		refcount_inc(&entry->refs);598		trace_btrfs_ordered_extent_dec_test_pending(inode, entry);599	}600	spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);601	return finished;602}603 604/*605 * used to drop a reference on an ordered extent.  This will free606 * the extent if the last reference is dropped607 */608void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)609{610	struct list_head *cur;611	struct btrfs_ordered_sum *sum;612 613	trace_btrfs_ordered_extent_put(entry->inode, entry);614 615	if (refcount_dec_and_test(&entry->refs)) {616		ASSERT(list_empty(&entry->root_extent_list));617		ASSERT(list_empty(&entry->log_list));618		ASSERT(RB_EMPTY_NODE(&entry->rb_node));619		if (entry->inode)620			btrfs_add_delayed_iput(entry->inode);621		while (!list_empty(&entry->list)) {622			cur = entry->list.next;623			sum = list_entry(cur, struct btrfs_ordered_sum, list);624			list_del(&sum->list);625			kvfree(sum);626		}627		kmem_cache_free(btrfs_ordered_extent_cache, entry);628	}629}630 631/*632 * remove an ordered extent from the tree.  No references are dropped633 * and waiters are woken up.634 */635void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,636				 struct btrfs_ordered_extent *entry)637{638	struct btrfs_root *root = btrfs_inode->root;639	struct btrfs_fs_info *fs_info = root->fs_info;640	struct rb_node *node;641	bool pending;642	bool freespace_inode;643 644	/*645	 * If this is a free space inode the thread has not acquired the ordered646	 * extents lockdep map.647	 */648	freespace_inode = btrfs_is_free_space_inode(btrfs_inode);649 650	btrfs_lockdep_acquire(fs_info, btrfs_trans_pending_ordered);651	/* This is paired with alloc_ordered_extent(). */652	spin_lock(&btrfs_inode->lock);653	btrfs_mod_outstanding_extents(btrfs_inode, -1);654	spin_unlock(&btrfs_inode->lock);655	if (root != fs_info->tree_root) {656		u64 release;657 658		if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags))659			release = entry->disk_num_bytes;660		else661			release = entry->num_bytes;662		btrfs_delalloc_release_metadata(btrfs_inode, release,663						test_bit(BTRFS_ORDERED_IOERR,664							 &entry->flags));665	}666 667	percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,668				 fs_info->delalloc_batch);669 670	spin_lock_irq(&btrfs_inode->ordered_tree_lock);671	node = &entry->rb_node;672	rb_erase(node, &btrfs_inode->ordered_tree);673	RB_CLEAR_NODE(node);674	if (btrfs_inode->ordered_tree_last == node)675		btrfs_inode->ordered_tree_last = NULL;676	set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);677	pending = test_and_clear_bit(BTRFS_ORDERED_PENDING, &entry->flags);678	spin_unlock_irq(&btrfs_inode->ordered_tree_lock);679 680	/*681	 * The current running transaction is waiting on us, we need to let it682	 * know that we're complete and wake it up.683	 */684	if (pending) {685		struct btrfs_transaction *trans;686 687		/*688		 * The checks for trans are just a formality, it should be set,689		 * but if it isn't we don't want to deref/assert under the spin690		 * lock, so be nice and check if trans is set, but ASSERT() so691		 * if it isn't set a developer will notice.692		 */693		spin_lock(&fs_info->trans_lock);694		trans = fs_info->running_transaction;695		if (trans)696			refcount_inc(&trans->use_count);697		spin_unlock(&fs_info->trans_lock);698 699		ASSERT(trans || BTRFS_FS_ERROR(fs_info));700		if (trans) {701			if (atomic_dec_and_test(&trans->pending_ordered))702				wake_up(&trans->pending_wait);703			btrfs_put_transaction(trans);704		}705	}706 707	btrfs_lockdep_release(fs_info, btrfs_trans_pending_ordered);708 709	spin_lock(&root->ordered_extent_lock);710	list_del_init(&entry->root_extent_list);711	root->nr_ordered_extents--;712 713	trace_btrfs_ordered_extent_remove(btrfs_inode, entry);714 715	if (!root->nr_ordered_extents) {716		spin_lock(&fs_info->ordered_root_lock);717		BUG_ON(list_empty(&root->ordered_root));718		list_del_init(&root->ordered_root);719		spin_unlock(&fs_info->ordered_root_lock);720	}721	spin_unlock(&root->ordered_extent_lock);722	wake_up(&entry->wait);723	if (!freespace_inode)724		btrfs_lockdep_release(fs_info, btrfs_ordered_extent);725}726 727static void btrfs_run_ordered_extent_work(struct btrfs_work *work)728{729	struct btrfs_ordered_extent *ordered;730 731	ordered = container_of(work, struct btrfs_ordered_extent, flush_work);732	btrfs_start_ordered_extent(ordered);733	complete(&ordered->completion);734}735 736/*737 * Wait for all the ordered extents in a root. Use @bg as range or do whole738 * range if it's NULL.739 */740u64 btrfs_wait_ordered_extents(struct btrfs_root *root, u64 nr,741			       const struct btrfs_block_group *bg)742{743	struct btrfs_fs_info *fs_info = root->fs_info;744	LIST_HEAD(splice);745	LIST_HEAD(skipped);746	LIST_HEAD(works);747	struct btrfs_ordered_extent *ordered, *next;748	u64 count = 0;749	u64 range_start, range_len;750	u64 range_end;751 752	if (bg) {753		range_start = bg->start;754		range_len = bg->length;755	} else {756		range_start = 0;757		range_len = U64_MAX;758	}759	range_end = range_start + range_len;760 761	mutex_lock(&root->ordered_extent_mutex);762	spin_lock(&root->ordered_extent_lock);763	list_splice_init(&root->ordered_extents, &splice);764	while (!list_empty(&splice) && nr) {765		ordered = list_first_entry(&splice, struct btrfs_ordered_extent,766					   root_extent_list);767 768		if (range_end <= ordered->disk_bytenr ||769		    ordered->disk_bytenr + ordered->disk_num_bytes <= range_start) {770			list_move_tail(&ordered->root_extent_list, &skipped);771			cond_resched_lock(&root->ordered_extent_lock);772			continue;773		}774 775		list_move_tail(&ordered->root_extent_list,776			       &root->ordered_extents);777		refcount_inc(&ordered->refs);778		spin_unlock(&root->ordered_extent_lock);779 780		btrfs_init_work(&ordered->flush_work,781				btrfs_run_ordered_extent_work, NULL);782		list_add_tail(&ordered->work_list, &works);783		btrfs_queue_work(fs_info->flush_workers, &ordered->flush_work);784 785		cond_resched();786		if (nr != U64_MAX)787			nr--;788		count++;789		spin_lock(&root->ordered_extent_lock);790	}791	list_splice_tail(&skipped, &root->ordered_extents);792	list_splice_tail(&splice, &root->ordered_extents);793	spin_unlock(&root->ordered_extent_lock);794 795	list_for_each_entry_safe(ordered, next, &works, work_list) {796		list_del_init(&ordered->work_list);797		wait_for_completion(&ordered->completion);798		btrfs_put_ordered_extent(ordered);799		cond_resched();800	}801	mutex_unlock(&root->ordered_extent_mutex);802 803	return count;804}805 806/*807 * Wait for @nr ordered extents that intersect the @bg, or the whole range of808 * the filesystem if @bg is NULL.809 */810void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,811			      const struct btrfs_block_group *bg)812{813	struct btrfs_root *root;814	LIST_HEAD(splice);815	u64 done;816 817	mutex_lock(&fs_info->ordered_operations_mutex);818	spin_lock(&fs_info->ordered_root_lock);819	list_splice_init(&fs_info->ordered_roots, &splice);820	while (!list_empty(&splice) && nr) {821		root = list_first_entry(&splice, struct btrfs_root,822					ordered_root);823		root = btrfs_grab_root(root);824		BUG_ON(!root);825		list_move_tail(&root->ordered_root,826			       &fs_info->ordered_roots);827		spin_unlock(&fs_info->ordered_root_lock);828 829		done = btrfs_wait_ordered_extents(root, nr, bg);830		btrfs_put_root(root);831 832		if (nr != U64_MAX)833			nr -= done;834 835		spin_lock(&fs_info->ordered_root_lock);836	}837	list_splice_tail(&splice, &fs_info->ordered_roots);838	spin_unlock(&fs_info->ordered_root_lock);839	mutex_unlock(&fs_info->ordered_operations_mutex);840}841 842/*843 * Start IO and wait for a given ordered extent to finish.844 *845 * Wait on page writeback for all the pages in the extent and the IO completion846 * code to insert metadata into the btree corresponding to the extent.847 */848void btrfs_start_ordered_extent(struct btrfs_ordered_extent *entry)849{850	u64 start = entry->file_offset;851	u64 end = start + entry->num_bytes - 1;852	struct btrfs_inode *inode = entry->inode;853	bool freespace_inode;854 855	trace_btrfs_ordered_extent_start(inode, entry);856 857	/*858	 * If this is a free space inode do not take the ordered extents lockdep859	 * map.860	 */861	freespace_inode = btrfs_is_free_space_inode(inode);862 863	/*864	 * pages in the range can be dirty, clean or writeback.  We865	 * start IO on any dirty ones so the wait doesn't stall waiting866	 * for the flusher thread to find them867	 */868	if (!test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))869		filemap_fdatawrite_range(inode->vfs_inode.i_mapping, start, end);870 871	if (!freespace_inode)872		btrfs_might_wait_for_event(inode->root->fs_info, btrfs_ordered_extent);873	wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE, &entry->flags));874}875 876/*877 * Used to wait on ordered extents across a large range of bytes.878 */879int btrfs_wait_ordered_range(struct btrfs_inode *inode, u64 start, u64 len)880{881	int ret = 0;882	int ret_wb = 0;883	u64 end;884	u64 orig_end;885	struct btrfs_ordered_extent *ordered;886 887	if (start + len < start) {888		orig_end = OFFSET_MAX;889	} else {890		orig_end = start + len - 1;891		if (orig_end > OFFSET_MAX)892			orig_end = OFFSET_MAX;893	}894 895	/* start IO across the range first to instantiate any delalloc896	 * extents897	 */898	ret = btrfs_fdatawrite_range(inode, start, orig_end);899	if (ret)900		return ret;901 902	/*903	 * If we have a writeback error don't return immediately. Wait first904	 * for any ordered extents that haven't completed yet. This is to make905	 * sure no one can dirty the same page ranges and call writepages()906	 * before the ordered extents complete - to avoid failures (-EEXIST)907	 * when adding the new ordered extents to the ordered tree.908	 */909	ret_wb = filemap_fdatawait_range(inode->vfs_inode.i_mapping, start, orig_end);910 911	end = orig_end;912	while (1) {913		ordered = btrfs_lookup_first_ordered_extent(inode, end);914		if (!ordered)915			break;916		if (ordered->file_offset > orig_end) {917			btrfs_put_ordered_extent(ordered);918			break;919		}920		if (ordered->file_offset + ordered->num_bytes <= start) {921			btrfs_put_ordered_extent(ordered);922			break;923		}924		btrfs_start_ordered_extent(ordered);925		end = ordered->file_offset;926		/*927		 * If the ordered extent had an error save the error but don't928		 * exit without waiting first for all other ordered extents in929		 * the range to complete.930		 */931		if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))932			ret = -EIO;933		btrfs_put_ordered_extent(ordered);934		if (end == 0 || end == start)935			break;936		end--;937	}938	return ret_wb ? ret_wb : ret;939}940 941/*942 * find an ordered extent corresponding to file_offset.  return NULL if943 * nothing is found, otherwise take a reference on the extent and return it944 */945struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,946							 u64 file_offset)947{948	struct rb_node *node;949	struct btrfs_ordered_extent *entry = NULL;950	unsigned long flags;951 952	spin_lock_irqsave(&inode->ordered_tree_lock, flags);953	node = ordered_tree_search(inode, file_offset);954	if (!node)955		goto out;956 957	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);958	if (!in_range(file_offset, entry->file_offset, entry->num_bytes))959		entry = NULL;960	if (entry) {961		refcount_inc(&entry->refs);962		trace_btrfs_ordered_extent_lookup(inode, entry);963	}964out:965	spin_unlock_irqrestore(&inode->ordered_tree_lock, flags);966	return entry;967}968 969/* Since the DIO code tries to lock a wide area we need to look for any ordered970 * extents that exist in the range, rather than just the start of the range.971 */972struct btrfs_ordered_extent *btrfs_lookup_ordered_range(973		struct btrfs_inode *inode, u64 file_offset, u64 len)974{975	struct rb_node *node;976	struct btrfs_ordered_extent *entry = NULL;977 978	spin_lock_irq(&inode->ordered_tree_lock);979	node = ordered_tree_search(inode, file_offset);980	if (!node) {981		node = ordered_tree_search(inode, file_offset + len);982		if (!node)983			goto out;984	}985 986	while (1) {987		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);988		if (range_overlaps(entry, file_offset, len))989			break;990 991		if (entry->file_offset >= file_offset + len) {992			entry = NULL;993			break;994		}995		entry = NULL;996		node = rb_next(node);997		if (!node)998			break;999	}1000out:1001	if (entry) {1002		refcount_inc(&entry->refs);1003		trace_btrfs_ordered_extent_lookup_range(inode, entry);1004	}1005	spin_unlock_irq(&inode->ordered_tree_lock);1006	return entry;1007}1008 1009/*1010 * Adds all ordered extents to the given list. The list ends up sorted by the1011 * file_offset of the ordered extents.1012 */1013void btrfs_get_ordered_extents_for_logging(struct btrfs_inode *inode,1014					   struct list_head *list)1015{1016	struct rb_node *n;1017 1018	btrfs_assert_inode_locked(inode);1019 1020	spin_lock_irq(&inode->ordered_tree_lock);1021	for (n = rb_first(&inode->ordered_tree); n; n = rb_next(n)) {1022		struct btrfs_ordered_extent *ordered;1023 1024		ordered = rb_entry(n, struct btrfs_ordered_extent, rb_node);1025 1026		if (test_bit(BTRFS_ORDERED_LOGGED, &ordered->flags))1027			continue;1028 1029		ASSERT(list_empty(&ordered->log_list));1030		list_add_tail(&ordered->log_list, list);1031		refcount_inc(&ordered->refs);1032		trace_btrfs_ordered_extent_lookup_for_logging(inode, ordered);1033	}1034	spin_unlock_irq(&inode->ordered_tree_lock);1035}1036 1037/*1038 * lookup and return any extent before 'file_offset'.  NULL is returned1039 * if none is found1040 */1041struct btrfs_ordered_extent *1042btrfs_lookup_first_ordered_extent(struct btrfs_inode *inode, u64 file_offset)1043{1044	struct rb_node *node;1045	struct btrfs_ordered_extent *entry = NULL;1046 1047	spin_lock_irq(&inode->ordered_tree_lock);1048	node = ordered_tree_search(inode, file_offset);1049	if (!node)1050		goto out;1051 1052	entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);1053	refcount_inc(&entry->refs);1054	trace_btrfs_ordered_extent_lookup_first(inode, entry);1055out:1056	spin_unlock_irq(&inode->ordered_tree_lock);1057	return entry;1058}1059 1060/*1061 * Lookup the first ordered extent that overlaps the range1062 * [@file_offset, @file_offset + @len).1063 *1064 * The difference between this and btrfs_lookup_first_ordered_extent() is1065 * that this one won't return any ordered extent that does not overlap the range.1066 * And the difference against btrfs_lookup_ordered_extent() is, this function1067 * ensures the first ordered extent gets returned.1068 */1069struct btrfs_ordered_extent *btrfs_lookup_first_ordered_range(1070			struct btrfs_inode *inode, u64 file_offset, u64 len)1071{1072	struct rb_node *node;1073	struct rb_node *cur;1074	struct rb_node *prev;1075	struct rb_node *next;1076	struct btrfs_ordered_extent *entry = NULL;1077 1078	spin_lock_irq(&inode->ordered_tree_lock);1079	node = inode->ordered_tree.rb_node;1080	/*1081	 * Here we don't want to use tree_search() which will use tree->last1082	 * and screw up the search order.1083	 * And __tree_search() can't return the adjacent ordered extents1084	 * either, thus here we do our own search.1085	 */1086	while (node) {1087		entry = rb_entry(node, struct btrfs_ordered_extent, rb_node);1088 1089		if (file_offset < entry->file_offset) {1090			node = node->rb_left;1091		} else if (file_offset >= entry_end(entry)) {1092			node = node->rb_right;1093		} else {1094			/*1095			 * Direct hit, got an ordered extent that starts at1096			 * @file_offset1097			 */1098			goto out;1099		}1100	}1101	if (!entry) {1102		/* Empty tree */1103		goto out;1104	}1105 1106	cur = &entry->rb_node;1107	/* We got an entry around @file_offset, check adjacent entries */1108	if (entry->file_offset < file_offset) {1109		prev = cur;1110		next = rb_next(cur);1111	} else {1112		prev = rb_prev(cur);1113		next = cur;1114	}1115	if (prev) {1116		entry = rb_entry(prev, struct btrfs_ordered_extent, rb_node);1117		if (range_overlaps(entry, file_offset, len))1118			goto out;1119	}1120	if (next) {1121		entry = rb_entry(next, struct btrfs_ordered_extent, rb_node);1122		if (range_overlaps(entry, file_offset, len))1123			goto out;1124	}1125	/* No ordered extent in the range */1126	entry = NULL;1127out:1128	if (entry) {1129		refcount_inc(&entry->refs);1130		trace_btrfs_ordered_extent_lookup_first_range(inode, entry);1131	}1132 1133	spin_unlock_irq(&inode->ordered_tree_lock);1134	return entry;1135}1136 1137/*1138 * Lock the passed range and ensures all pending ordered extents in it are run1139 * to completion.1140 *1141 * @inode:        Inode whose ordered tree is to be searched1142 * @start:        Beginning of range to flush1143 * @end:          Last byte of range to lock1144 * @cached_state: If passed, will return the extent state responsible for the1145 *                locked range. It's the caller's responsibility to free the1146 *                cached state.1147 *1148 * Always return with the given range locked, ensuring after it's called no1149 * order extent can be pending.1150 */1151void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,1152					u64 end,1153					struct extent_state **cached_state)1154{1155	struct btrfs_ordered_extent *ordered;1156	struct extent_state *cache = NULL;1157	struct extent_state **cachedp = &cache;1158 1159	if (cached_state)1160		cachedp = cached_state;1161 1162	while (1) {1163		lock_extent(&inode->io_tree, start, end, cachedp);1164		ordered = btrfs_lookup_ordered_range(inode, start,1165						     end - start + 1);1166		if (!ordered) {1167			/*1168			 * If no external cached_state has been passed then1169			 * decrement the extra ref taken for cachedp since we1170			 * aren't exposing it outside of this function1171			 */1172			if (!cached_state)1173				refcount_dec(&cache->refs);1174			break;1175		}1176		unlock_extent(&inode->io_tree, start, end, cachedp);1177		btrfs_start_ordered_extent(ordered);1178		btrfs_put_ordered_extent(ordered);1179	}1180}1181 1182/*1183 * Lock the passed range and ensure all pending ordered extents in it are run1184 * to completion in nowait mode.1185 *1186 * Return true if btrfs_lock_ordered_range does not return any extents,1187 * otherwise false.1188 */1189bool btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end,1190				  struct extent_state **cached_state)1191{1192	struct btrfs_ordered_extent *ordered;1193 1194	if (!try_lock_extent(&inode->io_tree, start, end, cached_state))1195		return false;1196 1197	ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1);1198	if (!ordered)1199		return true;1200 1201	btrfs_put_ordered_extent(ordered);1202	unlock_extent(&inode->io_tree, start, end, cached_state);1203 1204	return false;1205}1206 1207/* Split out a new ordered extent for this first @len bytes of @ordered. */1208struct btrfs_ordered_extent *btrfs_split_ordered_extent(1209			struct btrfs_ordered_extent *ordered, u64 len)1210{1211	struct btrfs_inode *inode = ordered->inode;1212	struct btrfs_root *root = inode->root;1213	struct btrfs_fs_info *fs_info = root->fs_info;1214	u64 file_offset = ordered->file_offset;1215	u64 disk_bytenr = ordered->disk_bytenr;1216	unsigned long flags = ordered->flags;1217	struct btrfs_ordered_sum *sum, *tmpsum;1218	struct btrfs_ordered_extent *new;1219	struct rb_node *node;1220	u64 offset = 0;1221 1222	trace_btrfs_ordered_extent_split(inode, ordered);1223 1224	ASSERT(!(flags & (1U << BTRFS_ORDERED_COMPRESSED)));1225 1226	/*1227	 * The entire bio must be covered by the ordered extent, but we can't1228	 * reduce the original extent to a zero length either.1229	 */1230	if (WARN_ON_ONCE(len >= ordered->num_bytes))1231		return ERR_PTR(-EINVAL);1232	/* We cannot split partially completed ordered extents. */1233	if (ordered->bytes_left) {1234		ASSERT(!(flags & ~BTRFS_ORDERED_TYPE_FLAGS));1235		if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes))1236			return ERR_PTR(-EINVAL);1237	}1238	/* We cannot split a compressed ordered extent. */1239	if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))1240		return ERR_PTR(-EINVAL);1241 1242	new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr,1243				   len, 0, flags, ordered->compress_type);1244	if (IS_ERR(new))1245		return new;1246 1247	/* One ref for the tree. */1248	refcount_inc(&new->refs);1249 1250	/*1251	 * Take the root's ordered_extent_lock to avoid a race with1252	 * btrfs_wait_ordered_extents() when updating the disk_bytenr and1253	 * disk_num_bytes fields of the ordered extent below. And we disable1254	 * IRQs because the inode's ordered_tree_lock is used in IRQ context1255	 * elsewhere.1256	 *1257	 * There's no concern about a previous caller of1258	 * btrfs_wait_ordered_extents() getting the trimmed ordered extent1259	 * before we insert the new one, because even if it gets the ordered1260	 * extent before it's trimmed and the new one inserted, right before it1261	 * uses it or during its use, the ordered extent might have been1262	 * trimmed in the meanwhile, and it missed the new ordered extent.1263	 * There's no way around this and it's harmless for current use cases,1264	 * so we take the root's ordered_extent_lock to fix that race during1265	 * trimming and silence tools like KCSAN.1266	 */1267	spin_lock_irq(&root->ordered_extent_lock);1268	spin_lock(&inode->ordered_tree_lock);1269 1270	/*1271	 * We don't have overlapping ordered extents (that would imply double1272	 * allocation of extents) and we checked above that the split length1273	 * does not cross the ordered extent's num_bytes field, so there's1274	 * no need to remove it and re-insert it in the tree.1275	 */1276	ordered->file_offset += len;1277	ordered->disk_bytenr += len;1278	ordered->num_bytes -= len;1279	ordered->disk_num_bytes -= len;1280	ordered->ram_bytes -= len;1281 1282	if (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags)) {1283		ASSERT(ordered->bytes_left == 0);1284		new->bytes_left = 0;1285	} else {1286		ordered->bytes_left -= len;1287	}1288 1289	if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags)) {1290		if (ordered->truncated_len > len) {1291			ordered->truncated_len -= len;1292		} else {1293			new->truncated_len = ordered->truncated_len;1294			ordered->truncated_len = 0;1295		}1296	}1297 1298	list_for_each_entry_safe(sum, tmpsum, &ordered->list, list) {1299		if (offset == len)1300			break;1301		list_move_tail(&sum->list, &new->list);1302		offset += sum->len;1303	}1304 1305	node = tree_insert(&inode->ordered_tree, new->file_offset, &new->rb_node);1306	if (unlikely(node))1307		btrfs_panic(fs_info, -EEXIST,1308			"inconsistency in ordered tree at offset %llu after split",1309			new->file_offset);1310	spin_unlock(&inode->ordered_tree_lock);1311 1312	list_add_tail(&new->root_extent_list, &root->ordered_extents);1313	root->nr_ordered_extents++;1314	spin_unlock_irq(&root->ordered_extent_lock);1315	return new;1316}1317 1318int __init ordered_data_init(void)1319{1320	btrfs_ordered_extent_cache = KMEM_CACHE(btrfs_ordered_extent, 0);1321	if (!btrfs_ordered_extent_cache)1322		return -ENOMEM;1323 1324	return 0;1325}1326 1327void __cold ordered_data_exit(void)1328{1329	kmem_cache_destroy(btrfs_ordered_extent_cache);1330}1331