Btrfs: don't continue setting up space cache when enospc

	}

	spin_unlock(&block_group->lock);

	/*

	 * We hit an ENOSPC when setting up the cache in this transaction, just

	 * skip doing the setup, we've already cleared the cache so we're safe.

	 */

	if (test_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags)) {

		ret = -ENOSPC;

		goto out_put;

	}

	/*

	 * Try to preallocate enough space based on how big the block group is.

	 * Keep in mind this has to include any pinned space which could end up

	ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages,

					      num_pages, num_pages,

					      &alloc_hint);

	/*

	 * Our cache requires contiguous chunks so that we don't modify a bunch

	 * of metadata or split extents when writing the cache out, which means

	 * we can enospc if we are heavily fragmented in addition to just normal

	 * out of space conditions.  So if we hit this just skip setting up any

	 * other block groups for this transaction, maybe we'll unpin enough

	 * space the next time around.

	 */

	if (!ret)

		dcs = BTRFS_DC_SETUP;

	else if (ret == -ENOSPC)

		set_bit(BTRFS_TRANS_CACHE_ENOSPC, &trans->transaction->flags);

	btrfs_free_reserved_data_space(inode, num_pages);

out_put:

#define BTRFS_TRANS_HAVE_FREE_BGS	0

#define BTRFS_TRANS_DIRTY_BG_RUN	1

#define BTRFS_TRANS_CACHE_ENOSPC	2

struct btrfs_transaction {

	u64 transid;