bcachefs: btree_ptr_v2

Add a new btree ptr type which contains the sequence number (random 64
bit cookie, actually) for that btree node - this lets us verify that
when we read in a btree node it really is the btree node we wanted.

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

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/bcachefs/btree_cache.h b/fs/bcachefs/btree_cache.h
index 270f7f8fb140..6e7edcaf6675 100644
--- a/fs/bcachefs/btree_cache.h
+++ b/fs/bcachefs/btree_cache.h
@@ -40,6 +40,8 @@ static inline u64 btree_ptr_hash_val(const struct bkey_i *k)
 	switch (k->k.type) {
 	case KEY_TYPE_btree_ptr:
 		return *((u64 *) bkey_i_to_btree_ptr_c(k)->v.start);
+	case KEY_TYPE_btree_ptr_v2:
+		return bkey_i_to_btree_ptr_v2_c(k)->v.seq;
 	default:
 		return 0;
 	}