From 6b81f194f345d15dd15601ee7b604a0640445895 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Thu, 1 Sep 2022 22:05:16 -0400 Subject: [PATCH] bcachefs: Fix six_lock_readers_add() Have to be careful with bit fields - when subtracting, this was overflowing into the write_locking bit. Signed-off-by: Kent Overstreet --- fs/bcachefs/btree_locking.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/bcachefs/btree_locking.c b/fs/bcachefs/btree_locking.c index 24d0ea9033802..158cb7ac64f28 100644 --- a/fs/bcachefs/btree_locking.c +++ b/fs/bcachefs/btree_locking.c @@ -10,10 +10,12 @@ struct lock_class_key bch2_btree_node_lock_key; static inline void six_lock_readers_add(struct six_lock *lock, int nr) { - if (!lock->readers) + if (lock->readers) + this_cpu_add(*lock->readers, nr); + else if (nr > 0) atomic64_add(__SIX_VAL(read_lock, nr), &lock->state.counter); else - this_cpu_add(*lock->readers, nr); + atomic64_sub(__SIX_VAL(read_lock, -nr), &lock->state.counter); } struct six_lock_count bch2_btree_node_lock_counts(struct btree_trans *trans, -- 2.39.5