From: Josef Bacik <josef@toxicpanda.com>
Date: Fri, 24 Jan 2020 09:32:41 -0500
Git-commit: 442b1ac5244ea2dc09d8aa688b41e0a0c4634b0a
Patch-mainline: 5.7-rc1
References: bsc#1176019
Subject: [PATCH] btrfs: hold a ref on the root in record_reloc_root_in_trans

We are recording this root in the transaction, so we need to hold a ref
on it until we do that.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/relocation.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 679dd3958ff2..0336a48d7d96 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2648,15 +2648,19 @@ static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans,
 {
 	struct btrfs_fs_info *fs_info = reloc_root->fs_info;
 	struct btrfs_root *root;
+	int ret;
 
 	if (reloc_root->last_trans == trans->transid)
 		return 0;
 
 	root = read_fs_root(fs_info, reloc_root->root_key.offset);
 	BUG_ON(IS_ERR(root));
+	BUG_ON(!btrfs_grab_fs_root(root));
 	BUG_ON(root->reloc_root != reloc_root);
+	ret = btrfs_record_root_in_trans(trans, root);
+	btrfs_put_fs_root(root);
 
-	return btrfs_record_root_in_trans(trans, root);
+	return ret;
 }
 
 static noinline_for_stack
-- 
2.26.2