bcachefs: bkey_ops.min_val_size

This adds a new field to bkey_ops for the minimum size of the value,
which standardizes that check and also enforces the new rule (previously
done somewhat ad-hoc) that we can extend value types by adding new
fields on to the end.

To make that work we do _not_ initialize min_val_size with sizeof,
instead we initialize it to the size of the first version of those
values.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/bcachefs/lru.h b/fs/bcachefs/lru.h
index 78a6076999ed..adb98429248e 100644
--- a/fs/bcachefs/lru.h
+++ b/fs/bcachefs/lru.h
@@ -51,6 +51,7 @@ void bch2_lru_pos_to_text(struct printbuf *, struct bpos);
 #define bch2_bkey_ops_lru ((struct bkey_ops) {	\
 	.key_invalid	= bch2_lru_invalid,	\
 	.val_to_text	= bch2_lru_to_text,	\
+	.min_val_size	= 8,			\
 })
 
 int bch2_lru_del(struct btree_trans *, u16, u64, u64);