The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From ab9b2c7b32e6be53cac2e23f5b2db66815a7d972 Mon Sep 17 00:00:00 2001

From: Josef Bacik josef@toxicpanda.com Date: Thu, 13 Feb 2020 10:47:30 -0500 Subject: [PATCH] btrfs: handle logged extent failure properly

If we're allocating a logged extent we attempt to insert an extent record for the file extent directly. We increase space_info->bytes_reserved, because the extent entry addition will call btrfs_update_block_group(), which will convert the ->bytes_reserved to ->bytes_used. However if we fail at any point while inserting the extent entry we will bail and leave space on ->bytes_reserved, which will trigger a WARN_ON() on umount. Fix this by pinning the space if we fail to insert, which is what happens in every other failure case that involves adding the extent entry.

CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Johannes Thumshirn johannes.thumshirn@wdc.com Reviewed-by: Nikolay Borisov nborisov@suse.com Reviewed-by: Qu Wenruo wqu@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 136fffb76428..7eef91d6c2b6 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4422,7 +4422,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans, ret = alloc_reserved_file_extent(trans, 0, root_objectid, 0, owner, offset, ins, 1); if (ret) - btrfs_pin_extent(fs_info, ins->objectid, ins->offset, 1); + btrfs_pin_extent(trans, ins->objectid, ins->offset, 1); btrfs_put_block_group(block_group); return ret; }