1 files changed, 130 insertions, 205 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f53470112670..1f091c2358a4 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -58,7 +58,6 @@
 #include "free-space-cache.h"
 #include "inode-map.h"
 #include "backref.h"
-#include "hash.h"
 #include "props.h"
 #include "qgroup.h"
 #include "dedupe.h"
@@ -102,7 +101,7 @@ static const unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
 };
 
 static int btrfs_setsize(struct inode *inode, struct iattr *attr);
-static int btrfs_truncate(struct inode *inode);
+static int btrfs_truncate(struct inode *inode, bool skip_writeback);
 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
 static noinline int cow_file_range(struct inode *inode,
 				   struct page *locked_page,
@@ -277,12 +276,12 @@ fail:
  * does the checks required to make sure the data is small enough
  * to fit as an inline extent.
  */
-static noinline int cow_file_range_inline(struct btrfs_root *root,
-					  struct inode *inode, u64 start,
+static noinline int cow_file_range_inline(struct inode *inode, u64 start,
 					  u64 end, size_t compressed_size,
 					  int compress_type,
 					  struct page **compressed_pages)
 {
+	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_trans_handle *trans;
 	u64 isize = i_size_read(inode);
@@ -458,7 +457,6 @@ static noinline void compress_file_range(struct inode *inode,
 					int *num_added)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
-	struct btrfs_root *root = BTRFS_I(inode)->root;
 	u64 blocksize = fs_info->sectorsize;
 	u64 actual_end;
 	u64 isize = i_size_read(inode);
@@ -580,11 +578,11 @@ cont:
 			/* we didn't compress the entire range, try
 			 * to make an uncompressed inline extent.
 			 */
-			ret = cow_file_range_inline(root, inode, start, end,
-					    0, BTRFS_COMPRESS_NONE, NULL);
+			ret = cow_file_range_inline(inode, start, end, 0,
+						    BTRFS_COMPRESS_NONE, NULL);
 		} else {
 			/* try making a compressed inline extent */
-			ret = cow_file_range_inline(root, inode, start, end,
+			ret = cow_file_range_inline(inode, start, end,
 						    total_compressed,
 						    compress_type, pages);
 		}
@@ -961,7 +959,6 @@ static noinline int cow_file_range(struct inode *inode,
 	u64 alloc_hint = 0;
 	u64 num_bytes;
 	unsigned long ram_size;
-	u64 disk_num_bytes;
 	u64 cur_alloc_size = 0;
 	u64 blocksize = fs_info->sectorsize;
 	struct btrfs_key ins;
@@ -979,14 +976,14 @@ static noinline int cow_file_range(struct inode *inode,
 
 	num_bytes = ALIGN(end - start + 1, blocksize);
 	num_bytes = max(blocksize,  num_bytes);
-	disk_num_bytes = num_bytes;
+	ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy));
 
 	inode_should_defrag(BTRFS_I(inode), start, end, num_bytes, SZ_64K);
 
 	if (start == 0) {
 		/* lets try to make an inline extent */
-		ret = cow_file_range_inline(root, inode, start, end, 0,
-					BTRFS_COMPRESS_NONE, NULL);
+		ret = cow_file_range_inline(inode, start, end, 0,
+					    BTRFS_COMPRESS_NONE, NULL);
 		if (ret == 0) {
 			/*
 			 * We use DO_ACCOUNTING here because we need the
@@ -1010,15 +1007,12 @@ static noinline int cow_file_range(struct inode *inode,
 		}
 	}
 
-	BUG_ON(disk_num_bytes >
-	       btrfs_super_total_bytes(fs_info->super_copy));
-
 	alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
 	btrfs_drop_extent_cache(BTRFS_I(inode), start,
 			start + num_bytes - 1, 0);
 
-	while (disk_num_bytes > 0) {
-		cur_alloc_size = disk_num_bytes;
+	while (num_bytes > 0) {
+		cur_alloc_size = num_bytes;
 		ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size,
 					   fs_info->sectorsize, 0, alloc_hint,
 					   &ins, 1, 1);
@@ -1082,11 +1076,10 @@ static noinline int cow_file_range(struct inode *inode,
 					     delalloc_end, locked_page,
 					     EXTENT_LOCKED | EXTENT_DELALLOC,
 					     page_ops);
-		if (disk_num_bytes < cur_alloc_size)
-			disk_num_bytes = 0;
+		if (num_bytes < cur_alloc_size)
+			num_bytes = 0;
 		else
-			disk_num_bytes -= cur_alloc_size;
-		num_bytes -= cur_alloc_size;
+			num_bytes -= cur_alloc_size;
 		alloc_hint = ins.objectid + ins.offset;
 		start += cur_alloc_size;
 		extent_reserved = false;
@@ -1262,6 +1255,8 @@ static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info,
 		list_del(&sums->list);
 		kfree(sums);
 	}
+	if (ret < 0)
+		return ret;
 	return 1;
 }
 
@@ -1394,10 +1389,23 @@ next_slot:
 				goto out_check;
 			if (btrfs_extent_readonly(fs_info, disk_bytenr))
 				goto out_check;
-			if (btrfs_cross_ref_exist(root, ino,
-						  found_key.offset -
-						  extent_offset, disk_bytenr))
+			ret = btrfs_cross_ref_exist(root, ino,
+						    found_key.offset -
+						    extent_offset, disk_bytenr);
+			if (ret) {
+				/*
+				 * ret could be -EIO if the above fails to read
+				 * metadata.
+				 */
+				if (ret < 0) {
+					if (cow_start != (u64)-1)
+						cur_offset = cow_start;
+					goto error;
+				}
+
+				WARN_ON_ONCE(nolock);
 				goto out_check;
+			}
 			disk_bytenr += extent_offset;
 			disk_bytenr += cur_offset - found_key.offset;
 			num_bytes = min(end + 1, extent_end) - cur_offset;
@@ -1415,10 +1423,22 @@ next_slot:
 			 * this ensure that csum for a given extent are
 			 * either valid or do not exist.
 			 */
-			if (csum_exist_in_range(fs_info, disk_bytenr,
-						num_bytes)) {
+			ret = csum_exist_in_range(fs_info, disk_bytenr,
+						  num_bytes);
+			if (ret) {
 				if (!nolock)
 					btrfs_end_write_no_snapshotting(root);
+
+				/*
+				 * ret could be -EIO if the above fails to read
+				 * metadata.
+				 */
+				if (ret < 0) {
+					if (cow_start != (u64)-1)
+						cur_offset = cow_start;
+					goto error;
+				}
+				WARN_ON_ONCE(nolock);
 				goto out_check;
 			}
 			if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr)) {
@@ -1847,7 +1867,7 @@ static void btrfs_clear_bit_hook(void *private_data,
 		 */
 		if (*bits & EXTENT_CLEAR_META_RESV &&
 		    root != fs_info->tree_root)
-			btrfs_delalloc_release_metadata(inode, len);
+			btrfs_delalloc_release_metadata(inode, len, false);
 
 		/* For sanity tests. */
 		if (btrfs_is_testing(fs_info))
@@ -1921,8 +1941,7 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
  * At IO completion time the cums attached on the ordered extent record
  * are inserted into the btree
  */
-static blk_status_t __btrfs_submit_bio_start(void *private_data, struct bio *bio,
-				    int mirror_num, unsigned long bio_flags,
+static blk_status_t btrfs_submit_bio_start(void *private_data, struct bio *bio,
 				    u64 bio_offset)
 {
 	struct inode *inode = private_data;
@@ -1941,9 +1960,8 @@ static blk_status_t __btrfs_submit_bio_start(void *private_data, struct bio *bio
  * At IO completion time the cums attached on the ordered extent record
  * are inserted into the btree
  */
-static blk_status_t __btrfs_submit_bio_done(void *private_data, struct bio *bio,
-			  int mirror_num, unsigned long bio_flags,
-			  u64 bio_offset)
+static blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
+			  int mirror_num)
 {
 	struct inode *inode = private_data;
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
@@ -2015,8 +2033,8 @@ static blk_status_t btrfs_submit_bio_hook(void *private_data, struct bio *bio,
 		/* we're doing a write, do the async checksumming */
 		ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, bio_flags,
 					  bio_offset, inode,
-					  __btrfs_submit_bio_start,
-					  __btrfs_submit_bio_done);
+					  btrfs_submit_bio_start,
+					  btrfs_submit_bio_done);
 		goto out;
 	} else if (!skip_sum) {
 		ret = btrfs_csum_one_bio(inode, bio, 0, 0);
@@ -2134,7 +2152,7 @@ again:
 
 	ClearPageChecked(page);
 	set_page_dirty(page);
-	btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);
+	btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, false);
 out:
 	unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
 			     &cached_state);
@@ -2754,12 +2772,10 @@ static void relink_file_extents(struct new_sa_defrag_extent *new)
 	struct sa_defrag_extent_backref *backref;
 	struct sa_defrag_extent_backref *prev = NULL;
 	struct inode *inode;
-	struct btrfs_root *root;
 	struct rb_node *node;
 	int ret;
 
 	inode = new->inode;
-	root = BTRFS_I(inode)->root;
 
 	path = btrfs_alloc_path();
 	if (!path)
@@ -3247,6 +3263,16 @@ static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
 				      start, (size_t)(end - start + 1));
 }
 
+/*
+ * btrfs_add_delayed_iput - perform a delayed iput on @inode
+ *
+ * @inode: The inode we want to perform iput on
+ *
+ * This function uses the generic vfs_inode::i_count to track whether we should
+ * just decrement it (in case it's > 1) or if this is the last iput then link
+ * the inode to the delayed iput machinery. Delayed iputs are processed at
+ * transaction commit time/superblock commit/cleaner kthread.
+ */
 void btrfs_add_delayed_iput(struct inode *inode)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
@@ -3256,12 +3282,8 @@ void btrfs_add_delayed_iput(struct inode *inode)
 		return;
 
 	spin_lock(&fs_info->delayed_iput_lock);
-	if (binode->delayed_iput_count == 0) {
-		ASSERT(list_empty(&binode->delayed_iput));
-		list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs);
-	} else {
-		binode->delayed_iput_count++;
-	}
+	ASSERT(list_empty(&binode->delayed_iput));
+	list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs);
 	spin_unlock(&fs_info->delayed_iput_lock);
 }
 
@@ -3274,13 +3296,7 @@ void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
 
 		inode = list_first_entry(&fs_info->delayed_iputs,
 				struct btrfs_inode, delayed_iput);
-		if (inode->delayed_iput_count) {
-			inode->delayed_iput_count--;
-			list_move_tail(&inode->delayed_iput,
-					&fs_info->delayed_iputs);
-		} else {
-			list_del_init(&inode->delayed_iput);
-		}
+		list_del_init(&inode->delayed_iput);
 		spin_unlock(&fs_info->delayed_iput_lock);
 		iput(&inode->vfs_inode);
 		spin_lock(&fs_info->delayed_iput_lock);
@@ -3350,7 +3366,7 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans,
 	struct btrfs_root *root = inode->root;
 	struct btrfs_block_rsv *block_rsv = NULL;
 	int reserve = 0;
-	int insert = 0;
+	bool insert = false;
 	int ret;
 
 	if (!root->orphan_block_rsv) {
@@ -3360,7 +3376,16 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans,
 			return -ENOMEM;
 	}
 
+	if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
+			      &inode->runtime_flags))
+		insert = true;
+
+	if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
+			      &inode->runtime_flags))
+		reserve = 1;
+
 	spin_lock(&root->orphan_lock);
+	/* If someone has created ->orphan_block_rsv, be happy to use it. */
 	if (!root->orphan_block_rsv) {
 		root->orphan_block_rsv = block_rsv;
 	} else if (block_rsv) {
@@ -3368,26 +3393,8 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans,
 		block_rsv = NULL;
 	}
 
-	if (!test_and_set_bit(BTRFS_INODE_HAS_ORPHAN_ITEM,
-			      &inode->runtime_flags)) {
-#if 0
-		/*
-		 * For proper ENOSPC handling, we should do orphan
-		 * cleanup when mounting. But this introduces backward
-		 * compatibility issue.
-		 */
-		if (!xchg(&root->orphan_item_inserted, 1))
-			insert = 2;
-		else
-			insert = 1;
-#endif
-		insert = 1;
+	if (insert)
 		atomic_inc(&root->orphan_inodes);
-	}
-
-	if (!test_and_set_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
-			      &inode->runtime_flags))
-		reserve = 1;
 	spin_unlock(&root->orphan_lock);
 
 	/* grab metadata reservation from transaction handle */
@@ -3411,7 +3418,7 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans,
 	}
 
 	/* insert an orphan item to track this unlinked/truncated file */
-	if (insert >= 1) {
+	if (insert) {
 		ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
 		if (ret) {
 			if (reserve) {
@@ -3435,15 +3442,6 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans,
 		ret = 0;
 	}
 
-	/* insert an orphan item to track subvolume contains orphan files */
-	if (insert >= 2) {
-		ret = btrfs_insert_orphan_item(trans, fs_info->tree_root,
-					       root->root_key.objectid);
-		if (ret && ret != -EEXIST) {
-			btrfs_abort_transaction(trans, ret);
-			return ret;
-		}
-	}
 	return 0;
 }
 
@@ -3644,7 +3642,7 @@ int btrfs_orphan_cleanup(struct btrfs_root *root)
 				goto out;
 			}
 
-			ret = btrfs_truncate(inode);
+			ret = btrfs_truncate(inode, false);
 			if (ret)
 				btrfs_orphan_del(NULL, BTRFS_I(inode));
 		} else {
@@ -4711,7 +4709,6 @@ delete:
 				if (updates) {
 					trans->delayed_ref_updates = 0;
 					ret = btrfs_run_delayed_refs(trans,
-								   fs_info,
 								   updates * 2);
 					if (ret && !err)
 						err = ret;
@@ -4751,8 +4748,7 @@ error:
 		unsigned long updates = trans->delayed_ref_updates;
 		if (updates) {
 			trans->delayed_ref_updates = 0;
-			ret = btrfs_run_delayed_refs(trans, fs_info,
-						     updates * 2);
+			ret = btrfs_run_delayed_refs(trans, updates * 2);
 			if (ret && !err)
 				err = ret;
 		}
@@ -4806,8 +4802,8 @@ again:
 	page = find_or_create_page(mapping, index, mask);
 	if (!page) {
 		btrfs_delalloc_release_space(inode, data_reserved,
-					     block_start, blocksize);
-		btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize);
+					     block_start, blocksize, true);
+		btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true);
 		ret = -ENOMEM;
 		goto out;
 	}
@@ -4874,8 +4870,8 @@ again:
 out_unlock:
 	if (ret)
 		btrfs_delalloc_release_space(inode, data_reserved, block_start,
-					     blocksize);
-	btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize);
+					     blocksize, true);
+	btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, (ret != 0));
 	unlock_page(page);
 	put_page(page);
 out:
@@ -5130,7 +5126,7 @@ static int btrfs_setsize(struct inode *inode, struct iattr *attr)
 		inode_dio_wait(inode);
 		btrfs_inode_resume_unlocked_dio(BTRFS_I(inode));
 
-		ret = btrfs_truncate(inode);
+		ret = btrfs_truncate(inode, newsize == oldsize);
 		if (ret && inode->i_nlink) {
 			int err;
 
@@ -5466,7 +5462,8 @@ no_delete:
 
 /*
  * this returns the key found in the dir entry in the location pointer.
- * If no dir entries were found, location->objectid is 0.
+ * If no dir entries were found, returns -ENOENT.
+ * If found a corrupted location in dir entry, returns -EUCLEAN.
  */
 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
 			       struct btrfs_key *location)
@@ -5484,27 +5481,27 @@ static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
 
 	di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(BTRFS_I(dir)),
 			name, namelen, 0);
-	if (IS_ERR(di))
+	if (!di) {
+		ret = -ENOENT;
+		goto out;
+	}
+	if (IS_ERR(di)) {
 		ret = PTR_ERR(di);
-
-	if (IS_ERR_OR_NULL(di))
-		goto out_err;
+		goto out;
+	}
 
 	btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
 	if (location->type != BTRFS_INODE_ITEM_KEY &&
 	    location->type != BTRFS_ROOT_ITEM_KEY) {
+		ret = -EUCLEAN;
 		btrfs_warn(root->fs_info,
 "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))",
 			   __func__, name, btrfs_ino(BTRFS_I(dir)),
 			   location->objectid, location->type, location->offset);
-		goto out_err;
 	}
 out:
 	btrfs_free_path(path);
 	return ret;
-out_err:
-	location->objectid = 0;
-	goto out;
 }
 
 /*
@@ -5807,9 +5804,6 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 	if (ret < 0)
 		return ERR_PTR(ret);
 
-	if (location.objectid == 0)
-		return ERR_PTR(-ENOENT);
-
 	if (location.type == BTRFS_INODE_ITEM_KEY) {
 		inode = btrfs_iget(dir->i_sb, &location, root, NULL);
 		return inode;
@@ -7443,76 +7437,6 @@ out:
 	return ret;
 }
 
-bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end)
-{
-	struct radix_tree_root *root = &inode->i_mapping->page_tree;
-	bool found = false;
-	void **pagep = NULL;
-	struct page *page = NULL;
-	unsigned long start_idx;
-	unsigned long end_idx;
-
-	start_idx = start >> PAGE_SHIFT;
-
-	/*
-	 * end is the last byte in the last page.  end == start is legal
-	 */
-	end_idx = end >> PAGE_SHIFT;
-
-	rcu_read_lock();
-
-	/* Most of the code in this while loop is lifted from
-	 * find_get_page.  It's been modified to begin searching from a
-	 * page and return just the first page found in that range.  If the
-	 * found idx is less than or equal to the end idx then we know that
-	 * a page exists.  If no pages are found or if those pages are
-	 * outside of the range then we're fine (yay!) */
-	while (page == NULL &&
-	       radix_tree_gang_lookup_slot(root, &pagep, NULL, start_idx, 1)) {
-		page = radix_tree_deref_slot(pagep);
-		if (unlikely(!page))
-			break;
-
-		if (radix_tree_exception(page)) {
-			if (radix_tree_deref_retry(page)) {
-				page = NULL;
-				continue;
-			}
-			/*
-			 * Otherwise, shmem/tmpfs must be storing a swap entry
-			 * here as an exceptional entry: so return it without
-			 * attempting to raise page count.
-			 */
-			page = NULL;
-			break; /* TODO: Is this relevant for this use case? */
-		}
-
-		if (!page_cache_get_speculative(page)) {
-			page = NULL;
-			continue;
-		}
-
-		/*
-		 * Has the page moved?
-		 * This is part of the lockless pagecache protocol. See
-		 * include/linux/pagemap.h for details.
-		 */
-		if (unlikely(page != *pagep)) {
-			put_page(page);
-			page = NULL;
-		}
-	}
-
-	if (page) {
-		if (page->index <= end_idx)
-			found = true;
-		put_page(page);
-	}
-
-	rcu_read_unlock();
-	return found;
-}
-
 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
 			      struct extent_state **cached_state, int writing)
 {
@@ -7538,8 +7462,8 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
 		 * get stale data.
 		 */
 		if (!ordered &&
-		    (!writing ||
-		     !btrfs_page_exists_in_range(inode, lockstart, lockend)))
+		    (!writing || !filemap_range_has_page(inode->i_mapping,
+							 lockstart, lockend)))
 			break;
 
 		unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
@@ -8270,9 +8194,8 @@ static void btrfs_endio_direct_write(struct bio *bio)
 	bio_put(bio);
 }
 
-static blk_status_t __btrfs_submit_bio_start_direct_io(void *private_data,
-				    struct bio *bio, int mirror_num,
-				    unsigned long bio_flags, u64 offset)
+static blk_status_t btrfs_submit_bio_start_direct_io(void *private_data,
+				    struct bio *bio, u64 offset)
 {
 	struct inode *inode = private_data;
 	blk_status_t ret;
@@ -8298,13 +8221,13 @@ static void btrfs_end_dio_bio(struct bio *bio)
 		err = dip->subio_endio(dip->inode, btrfs_io_bio(bio), err);
 
 	if (err) {
-		dip->errors = 1;
-
 		/*
-		 * before atomic variable goto zero, we must make sure
-		 * dip->errors is perceived to be set.
+		 * We want to perceive the errors flag being set before
+		 * decrementing the reference count. We don't need a barrier
+		 * since atomic operations with a return value are fully
+		 * ordered as per atomic_t.txt
 		 */
-		smp_mb__before_atomic();
+		dip->errors = 1;
 	}
 
 	/* if there are more bios still pending for this dio, just exit */
@@ -8352,9 +8275,8 @@ static inline blk_status_t btrfs_lookup_and_bind_dio_csum(struct inode *inode,
 	return 0;
 }
 
-static inline blk_status_t
-__btrfs_submit_dio_bio(struct bio *bio, struct inode *inode, u64 file_offset,
-		       int async_submit)
+static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio,
+		struct inode *inode, u64 file_offset, int async_submit)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_dio_private *dip = bio->bi_private;
@@ -8377,8 +8299,8 @@ __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode, u64 file_offset,
 	if (write && async_submit) {
 		ret = btrfs_wq_submit_bio(fs_info, bio, 0, 0,
 					  file_offset, inode,
-					  __btrfs_submit_bio_start_direct_io,
-					  __btrfs_submit_bio_done);
+					  btrfs_submit_bio_start_direct_io,
+					  btrfs_submit_bio_done);
 		goto err;
 	} else if (write) {
 		/*
@@ -8464,7 +8386,7 @@ static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
 		 */
 		atomic_inc(&dip->pending_bios);
 
-		status = __btrfs_submit_dio_bio(bio, inode, file_offset,
+		status = btrfs_submit_dio_bio(bio, inode, file_offset,
 						async_submit);
 		if (status) {
 			bio_put(bio);
@@ -8484,7 +8406,7 @@ static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
 	} while (submit_len > 0);
 
 submit:
-	status = __btrfs_submit_dio_bio(bio, inode, file_offset, async_submit);
+	status = btrfs_submit_dio_bio(bio, inode, file_offset, async_submit);
 	if (!status)
 		return 0;
 
@@ -8492,10 +8414,11 @@ submit:
 out_err:
 	dip->errors = 1;
 	/*
-	 * before atomic variable goto zero, we must
-	 * make sure dip->errors is perceived to be set.
+	 * Before atomic variable goto zero, we must  make sure dip->errors is
+	 * perceived to be set. This ordering is ensured by the fact that an
+	 * atomic operations with a return value are fully ordered as per
+	 * atomic_t.txt
 	 */
-	smp_mb__before_atomic();
 	if (atomic_dec_and_test(&dip->pending_bios))
 		bio_io_error(dip->orig_bio);
 
@@ -8713,7 +8636,7 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 		if (ret < 0 && ret != -EIOCBQUEUED) {
 			if (dio_data.reserve)
 				btrfs_delalloc_release_space(inode, data_reserved,
-					offset, dio_data.reserve);
+					offset, dio_data.reserve, true);
 			/*
 			 * On error we might have left some ordered extents
 			 * without submitting corresponding bios for them, so
@@ -8729,8 +8652,8 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 					false);
 		} else if (ret >= 0 && (size_t)ret < count)
 			btrfs_delalloc_release_space(inode, data_reserved,
-					offset, count - (size_t)ret);
-		btrfs_delalloc_release_extents(BTRFS_I(inode), count);
+					offset, count - (size_t)ret, true);
+		btrfs_delalloc_release_extents(BTRFS_I(inode), count, false);
 	}
 out:
 	if (wakeup)
@@ -9045,7 +8968,8 @@ again:
 		if (reserved_space < PAGE_SIZE) {
 			end = page_start + reserved_space - 1;
 			btrfs_delalloc_release_space(inode, data_reserved,
-					page_start, PAGE_SIZE - reserved_space);
+					page_start, PAGE_SIZE - reserved_space,
+					true);
 		}
 	}
 
@@ -9095,23 +9019,23 @@ again:
 
 out_unlock:
 	if (!ret) {
-		btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);
+		btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, true);
 		sb_end_pagefault(inode->i_sb);
 		extent_changeset_free(data_reserved);
 		return VM_FAULT_LOCKED;
 	}
 	unlock_page(page);
 out:
-	btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);
+	btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, (ret != 0));
 	btrfs_delalloc_release_space(inode, data_reserved, page_start,
-				     reserved_space);
+				     reserved_space, (ret != 0));
 out_noreserve:
 	sb_end_pagefault(inode->i_sb);
 	extent_changeset_free(data_reserved);
 	return ret;
 }
 
-static int btrfs_truncate(struct inode *inode)
+static int btrfs_truncate(struct inode *inode, bool skip_writeback)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -9122,10 +9046,12 @@ static int btrfs_truncate(struct inode *inode)
 	u64 mask = fs_info->sectorsize - 1;
 	u64 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1);
 
-	ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
-				       (u64)-1);
-	if (ret)
-		return ret;
+	if (!skip_writeback) {
+		ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
+					       (u64)-1);
+		if (ret)
+			return ret;
+	}
 
 	/*
 	 * Yes ladies and gentlemen, this is indeed ugly.  The fact is we have
@@ -9335,7 +9261,6 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
 	ei->dir_index = 0;
 	ei->last_unlink_trans = 0;
 	ei->last_log_commit = 0;
-	ei->delayed_iput_count = 0;
 
 	spin_lock_init(&ei->lock);
 	ei->outstanding_extents = 0;
@@ -9455,7 +9380,7 @@ static void init_once(void *foo)
 	inode_init_once(&ei->vfs_inode);
 }
 
-void btrfs_destroy_cachep(void)
+void __cold btrfs_destroy_cachep(void)
 {
 	/*
 	 * Make sure all delayed rcu free inodes are flushed before we