bcachefs: btree_bkey_cached_common->cached

Add a type descriptor to btree_bkey_cached_common - there's no reason
not to since we've got padding that was otherwise unused, and this is a
nice cleanup (and helpful in later patches).
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_iter.c

@@ -3021,8 +3021,7 @@ void bch2_trans_exit(struct btree_trans *trans)
 
 static void __maybe_unused
 bch2_btree_path_node_to_text(struct printbuf *out,
-			     struct btree_bkey_cached_common *b,
-			     bool cached)
+			     struct btree_bkey_cached_common *b)
 {
 	struct six_lock_count c = six_lock_counts(&b->lock);
 	struct task_struct *owner;
@@ -3035,7 +3034,7 @@ bch2_btree_path_node_to_text(struct printbuf *out,
 
 	prt_printf(out, "    l=%u %s:",
 	       b->level, bch2_btree_ids[b->btree_id]);
-	bch2_bpos_to_text(out, btree_node_pos(b, cached));
+	bch2_bpos_to_text(out, btree_node_pos(b));
 
 	prt_printf(out, "    locks %u:%u:%u held by pid %u",
 		   c.n[0], c.n[1], c.n[2], pid);
@@ -3068,7 +3067,7 @@ void bch2_btree_trans_to_text(struct printbuf *out, struct btree_trans *trans)
 			    !IS_ERR_OR_NULL(b = (void *) READ_ONCE(path->l[l].b))) {
 				prt_printf(out, "    %c l=%u ",
 					   lock_types[btree_node_locked_type(path, l)], l);
-				bch2_btree_path_node_to_text(out, b, path->cached);
+				bch2_btree_path_node_to_text(out, b);
 				prt_printf(out, "\n");
 			}
 		}
@@ -3086,7 +3085,7 @@ void bch2_btree_trans_to_text(struct printbuf *out, struct btree_trans *trans)
 		bch2_bpos_to_text(out, trans->locking_pos);
 
 		prt_printf(out, " node ");
-		bch2_btree_path_node_to_text(out, b, path->cached);
+		bch2_btree_path_node_to_text(out, b);
 		prt_printf(out, "\n");
 	}
 }

fs/bcachefs/btree_key_cache.c

@@ -204,6 +204,7 @@ bkey_cached_alloc(struct btree_trans *trans,
 		INIT_LIST_HEAD(&ck->list);
 		__six_lock_init(&ck->c.lock, "b->c.lock", &bch2_btree_node_lock_key);
 		lockdep_set_novalidate_class(&ck->c.lock);
+		ck->c.cached = true;
 		BUG_ON(!six_trylock_intent(&ck->c.lock));
 		BUG_ON(!six_trylock_write(&ck->c.lock));
 		return ck;

fs/bcachefs/btree_locking.c

@@ -144,8 +144,7 @@ int __bch2_btree_node_lock(struct btree_trans *trans,
 
 		/* Must lock btree nodes in key order: */
 		if (btree_node_locked(linked, level) &&
-		    bpos_cmp(pos, btree_node_pos(&linked->l[level].b->c,
-						 linked->cached)) <= 0) {
+		    bpos_cmp(pos, btree_node_pos(&linked->l[level].b->c)) <= 0) {
 			reason = 7;
 			goto deadlock;
 		}

fs/bcachefs/btree_types.h

@@ -63,6 +63,7 @@ struct btree_bkey_cached_common {
 	struct six_lock		lock;
 	u8			level;
 	u8			btree_id;
+	bool			cached;
 };
 
 struct btree {
@@ -335,10 +336,9 @@ struct bkey_cached {
 	struct bkey_i		*k;
 };
 
-static inline struct bpos btree_node_pos(struct btree_bkey_cached_common *b,
-					 bool cached)
+static inline struct bpos btree_node_pos(struct btree_bkey_cached_common *b)
 {
-	return !cached
+	return !b->cached
 		? container_of(b, struct btree, c)->key.k.p
 		: container_of(b, struct bkey_cached, c)->key.pos;
 }