bcachefs: KEY_TYPE_alloc_v4

This introduces a new alloc key which doesn't use varints. Soon we'll be
adding backpointers and storing them in alloc keys, which means our
pack/unpack workflow for alloc keys won't really work - we'll need to be
mutating alloc keys in place.

Instead of bch2_alloc_unpack(), we now have bch2_alloc_to_v4() that
converts older types of alloc keys to v4 if needed.

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

1 files changed, 8 insertions, 0 deletions

diff --git a/fs/bcachefs/buckets.h b/fs/bcachefs/buckets.h
index 90f53e677281..4937d7939c2b 100644
--- a/fs/bcachefs/buckets.h
+++ b/fs/bcachefs/buckets.h
@@ -97,6 +97,14 @@ static inline size_t PTR_BUCKET_NR(const struct bch_dev *ca,
 	return sector_to_bucket(ca, ptr->offset);
 }
 
+static inline struct bpos PTR_BUCKET_POS(const struct bch_fs *c,
+				   const struct bch_extent_ptr *ptr)
+{
+	struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
+
+	return POS(ptr->dev, PTR_BUCKET_NR(ca, ptr));
+}
+
 static inline struct bucket *PTR_GC_BUCKET(struct bch_dev *ca,
 					   const struct bch_extent_ptr *ptr)
 {