1 files changed, 14 insertions, 82 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b531c36455d8..830d261d0e6b 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -359,10 +359,14 @@ static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 
 	tree = &BTRFS_I(page->mapping->host)->io_tree;
 
-	if (page->private == EXTENT_PAGE_PRIVATE)
+	if (page->private == EXTENT_PAGE_PRIVATE) {
+		WARN_ON(1);
 		goto out;
-	if (!page->private)
+	}
+	if (!page->private) {
+		WARN_ON(1);
 		goto out;
+	}
 	len = page->private >> 2;
 	WARN_ON(len == 0);
 
@@ -843,7 +847,6 @@ static const struct address_space_operations btree_aops = {
 	.writepages	= btree_writepages,
 	.releasepage	= btree_releasepage,
 	.invalidatepage = btree_invalidatepage,
-	.sync_page	= block_sync_page,
 #ifdef CONFIG_MIGRATION
 	.migratepage	= btree_migratepage,
 #endif
@@ -1327,82 +1330,6 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 }
 
 /*
- * this unplugs every device on the box, and it is only used when page
- * is null
- */
-static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-	struct btrfs_device *device;
-	struct btrfs_fs_info *info;
-
-	info = (struct btrfs_fs_info *)bdi->unplug_io_data;
-	list_for_each_entry(device, &info->fs_devices->devices, dev_list) {
-		if (!device->bdev)
-			continue;
-
-		bdi = blk_get_backing_dev_info(device->bdev);
-		if (bdi->unplug_io_fn)
-			bdi->unplug_io_fn(bdi, page);
-	}
-}
-
-static void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
-{
-	struct inode *inode;
-	struct extent_map_tree *em_tree;
-	struct extent_map *em;
-	struct address_space *mapping;
-	u64 offset;
-
-	/* the generic O_DIRECT read code does this */
-	if (1 || !page) {
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-
-	/*
-	 * page->mapping may change at any time.  Get a consistent copy
-	 * and use that for everything below
-	 */
-	smp_mb();
-	mapping = page->mapping;
-	if (!mapping)
-		return;
-
-	inode = mapping->host;
-
-	/*
-	 * don't do the expensive searching for a small number of
-	 * devices
-	 */
-	if (BTRFS_I(inode)->root->fs_info->fs_devices->open_devices <= 2) {
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-
-	offset = page_offset(page);
-
-	em_tree = &BTRFS_I(inode)->extent_tree;
-	read_lock(&em_tree->lock);
-	em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
-	read_unlock(&em_tree->lock);
-	if (!em) {
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-
-	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
-		free_extent_map(em);
-		__unplug_io_fn(bdi, page);
-		return;
-	}
-	offset = offset - em->start;
-	btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree,
-			  em->block_start + offset, page);
-	free_extent_map(em);
-}
-
-/*
  * If this fails, caller must call bdi_destroy() to get rid of the
  * bdi again.
  */
@@ -1416,8 +1343,6 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
 		return err;
 
 	bdi->ra_pages	= default_backing_dev_info.ra_pages;
-	bdi->unplug_io_fn	= btrfs_unplug_io_fn;
-	bdi->unplug_io_data	= info;
 	bdi->congested_fn	= btrfs_congested_fn;
 	bdi->congested_data	= info;
 	return 0;
@@ -1550,6 +1475,7 @@ static int transaction_kthread(void *arg)
 		spin_unlock(&root->fs_info->new_trans_lock);
 
 		trans = btrfs_join_transaction(root, 1);
+		BUG_ON(IS_ERR(trans));
 		if (transid == trans->transid) {
 			ret = btrfs_commit_transaction(trans, root);
 			BUG_ON(ret);
@@ -2453,10 +2379,14 @@ int btrfs_commit_super(struct btrfs_root *root)
 	up_write(&root->fs_info->cleanup_work_sem);
 
 	trans = btrfs_join_transaction(root, 1);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
 	ret = btrfs_commit_transaction(trans, root);
 	BUG_ON(ret);
 	/* run commit again to drop the original snapshot */
 	trans = btrfs_join_transaction(root, 1);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
 	btrfs_commit_transaction(trans, root);
 	ret = btrfs_write_and_wait_transaction(NULL, root);
 	BUG_ON(ret);
@@ -2484,7 +2414,7 @@ int close_ctree(struct btrfs_root *root)
 	 * ERROR state on disk.
 	 *
 	 * 2. when btrfs flips readonly just in btrfs_commit_super,
-	 * and in such case, btrfs cannnot write sb via btrfs_commit_super,
+	 * and in such case, btrfs cannot write sb via btrfs_commit_super,
 	 * and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
 	 * btrfs will cleanup all FS resources first and write sb then.
 	 */
@@ -2554,6 +2484,8 @@ int close_ctree(struct btrfs_root *root)
 	kfree(fs_info->chunk_root);
 	kfree(fs_info->dev_root);
 	kfree(fs_info->csum_root);
+	kfree(fs_info);
+
 	return 0;
 }