bcachefs: New and improved topology repair code

This splits out btree topology repair into a separate pass, and makes
some improvements:
 - When we have to pick which of two overlapping nodes to drop keys
   from, we use the btree node header sequence number to preserve the
   newer node

 - the gc code has been changed so that it doesn't bail out if we're
   continuing/ignoring on fsck error - this way the dump tool can skip
   running the repair pass but still walk all reachable metadata

 - add a new superblock flag indicating when a filesystem is known to
   have btree topology issues, and the topology repair pass should be
   run

 - changing the start/end of a node might mean keys in that node have to
   be deleted: this patch handles that better by splitting it out into a
   separate function and running it explicitly in the topology repair
   code, previously those keys were only being dropped when the btree
   node was read in.

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

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/bcachefs/btree_io.h b/fs/bcachefs/btree_io.h
index c8a8b05a19b0..cadcf7f886d7 100644
--- a/fs/bcachefs/btree_io.h
+++ b/fs/bcachefs/btree_io.h
@@ -131,6 +131,8 @@ static inline void bset_encrypt(struct bch_fs *c, struct bset *i, unsigned offse
 
 void bch2_btree_sort_into(struct bch_fs *, struct btree *, struct btree *);
 
+void bch2_btree_node_drop_keys_outside_node(struct btree *);
+
 void bch2_btree_build_aux_trees(struct btree *);
 void bch2_btree_init_next(struct bch_fs *, struct btree *,
 			 struct btree_iter *);