From: Josef Bacik <josef@toxicpanda.com>
Date: Wed, 20 Nov 2019 19:49:20 +0000 (-0800)
Subject: btrfs: hold a ref on the root in record_reloc_root_in_trans
X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0b41c3eefd917424c3efb1a0ffdf33c83cb3049c;p=linux

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>
---

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index dfd3d9053301..c3cf582f943f 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2563,15 +2563,20 @@ 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);
+	if (!btrfs_grab_fs_root(root))
+		BUG();
 	BUG_ON(IS_ERR(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