[PATCH 23/43] btrfs: hold a ref on the root in merge_reloc_roots

Josef Bacik
2020-01-17T21:26:49Z

We look up the corresponding root for the reloc root, we need to hold a
ref while we're messing with it.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/relocation.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 53df57b59bc3..79430a4245b5 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2546,10 +2546,13 @@ void merge_reloc_roots(struct reloc_control *rc)
if (btrfs_root_refs(&reloc_root->root_item) > 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 = merge_reloc_root(rc, root);
+ btrfs_put_fs_root(root);
if (ret) {
if (list_empty(&reloc_root->root_list))
list_add_tail(&reloc_root->root_list,
--
2.24.1