bcachefs: Btree key cache coherency

 - Updates to non key cache iterators will now be transparently
   redirected to the key cache for cached btrees.

 - Except when creating new keys: then the update goes to underlying
   btree

For for iterating over a cached btree to work, we need to ensure that if
a key exists in the key cache, it also exists in the btree - otherwise
the iterator code will skip past it and not check the key cache.

Otherwise, for consistency, all updates should go to the same place -
the key cache.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 0 insertions, 2 deletions

diff --git a/fs/bcachefs/btree_update.h b/fs/bcachefs/btree_update.h
index 5e5a1b5e750e..d9a406a28f47 100644
--- a/fs/bcachefs/btree_update.h
+++ b/fs/bcachefs/btree_update.h
@@ -76,8 +76,6 @@ int bch2_btree_node_update_key_get_iter(struct btree_trans *,
 int bch2_trans_update_extent(struct btree_trans *, struct btree_iter *,
 			     struct bkey_i *, enum btree_update_flags);
 
-int __must_check bch2_trans_update_by_path(struct btree_trans *, struct btree_path *,
-				   struct bkey_i *, enum btree_update_flags);
 int __must_check bch2_trans_update(struct btree_trans *, struct btree_iter *,
 				   struct bkey_i *, enum btree_update_flags);