bcachefs: Kill memset() in bch2_btree_iter_init()

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

fs/bcachefs/bcachefs_format.h

@@ -307,6 +307,13 @@ struct bkey_i {
 	struct bch_val	v;
 };
 
+#define POS_KEY(_pos)							\
+((struct bkey) {							\
+	.u64s		= BKEY_U64s,					\
+	.format		= KEY_FORMAT_CURRENT,				\
+	.p		= _pos,						\
+})
+
 #define KEY(_inode, _offset, _size)					\
 ((struct bkey) {							\
 	.u64s		= BKEY_U64s,					\

fs/bcachefs/btree_iter.h

@@ -445,14 +445,17 @@ static inline void bch2_trans_iter_init_common(struct btree_trans *trans,
 					  unsigned flags,
 					  unsigned long ip)
 {
-	memset(iter, 0, sizeof(*iter));
-	iter->trans	= trans;
-	iter->btree_id	= btree_id;
-	iter->flags	= flags;
-	iter->snapshot	= pos.snapshot;
-	iter->pos	= pos;
-	iter->k.p	= pos;
-
+	iter->trans		= trans;
+	iter->update_path	= NULL;
+	iter->key_cache_path	= NULL;
+	iter->btree_id		= btree_id;
+	iter->min_depth		= 0;
+	iter->flags		= flags;
+	iter->snapshot		= pos.snapshot;
+	iter->pos		= pos;
+	iter->k			= POS_KEY(pos);
+	iter->journal_idx	= 0;
+	iter->journal_pos	= POS_MIN;
 #ifdef CONFIG_BCACHEFS_DEBUG
 	iter->ip_allocated = ip;
 #endif

fs/bcachefs/btree_types.h

@@ -287,8 +287,7 @@ struct btree_iter {
 	struct btree_path	*key_cache_path;
 
 	enum btree_id		btree_id:8;
-	unsigned		min_depth:3;
-	unsigned		advanced:1;
+	u8			min_depth;
 
 	/* btree_iter_copy starts here: */
 	u16			flags;