From 9649bd9a29a7da97eca456befd275ee16e3a2291 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Thu, 4 May 2023 12:04:25 +0100 Subject: [PATCH] btrfs: assert tree lock is held when linking free space When linking a free space entry, at link_free_space(), the caller should be holding the spinlock 'tree_lock' of the given btrfs_free_space_ctl argument, which is necessary for manipulating the red black tree of free space entries (done by tree_insert_offset(), which already asserts the lock is held) and for manipulating the 'free_space', 'free_extents', 'discardable_extents' and 'discardable_bytes' counters of the given struct btrfs_free_space_ctl. So assert that the spinlock 'tree_lock' of the given btrfs_free_space_ctl is held by the current task. We have multiple code paths that end up calling link_free_space(), and all currently take the lock before calling it. Reviewed-by: Anand Jain Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/free-space-cache.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index f3361ebfef4a..d349ba39820a 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -1850,6 +1850,8 @@ static int link_free_space(struct btrfs_free_space_ctl *ctl, { int ret = 0; + lockdep_assert_held(&ctl->tree_lock); + ASSERT(info->bytes || info->bitmap); ret = tree_insert_offset(ctl, NULL, info); if (ret)