bcachefs: bch2_btree_bit_mod()

New helper for bitset btrees.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_update.h

@@ -72,6 +72,8 @@ int bch2_btree_delete_range_trans(struct btree_trans *, enum btree_id,
 int bch2_btree_delete_range(struct bch_fs *, enum btree_id,
 			    struct bpos, struct bpos, unsigned, u64 *);
 
+int bch2_btree_bit_mod(struct btree_trans *, enum btree_id, struct bpos, bool);
+
 int bch2_btree_node_rewrite(struct btree_trans *, struct btree_iter *,
 			    struct btree *, unsigned);
 void bch2_btree_node_rewrite_async(struct bch_fs *, struct btree *);

fs/bcachefs/btree_update_leaf.c

@@ -1996,6 +1996,24 @@ int bch2_btree_delete_range(struct bch_fs *c, enum btree_id id,
 	return ret;
 }
 
+int bch2_btree_bit_mod(struct btree_trans *trans, enum btree_id btree,
+		       struct bpos pos, bool set)
+{
+	struct bkey_i *k;
+	int ret = 0;
+
+	k = bch2_trans_kmalloc_nomemzero(trans, sizeof(*k));
+	ret = PTR_ERR_OR_ZERO(k);
+	if (unlikely(ret))
+		return ret;
+
+	bkey_init(&k->k);
+	k->k.type = set ? KEY_TYPE_set : KEY_TYPE_deleted;
+	k->k.p = pos;
+
+	return bch2_trans_update_buffered(trans, btree, k);
+}
+
 static int __bch2_trans_log_msg(darray_u64 *entries, const char *fmt, va_list args)
 {
 	struct printbuf buf = PRINTBUF;

fs/bcachefs/lru.c

@@ -41,28 +41,12 @@ void bch2_lru_pos_to_text(struct printbuf *out, struct bpos lru)
 }
 
 static int __bch2_lru_set(struct btree_trans *trans, u16 lru_id,
-			u64 dev_bucket, u64 time, unsigned key_type)
+			  u64 dev_bucket, u64 time, bool set)
 {
-	struct bkey_i *k;
-	int ret = 0;
-
-	if (!time)
-		return 0;
-
-	k = bch2_trans_kmalloc_nomemzero(trans, sizeof(*k));
-	ret = PTR_ERR_OR_ZERO(k);
-	if (unlikely(ret))
-		return ret;
-
-	bkey_init(&k->k);
-	k->k.type = key_type;
-	k->k.p = lru_pos(lru_id, dev_bucket, time);
-
-	EBUG_ON(lru_pos_id(k->k.p) != lru_id);
-	EBUG_ON(lru_pos_time(k->k.p) != time);
-	EBUG_ON(k->k.p.offset != dev_bucket);
-
-	return bch2_trans_update_buffered(trans, BTREE_ID_lru, k);
+	return time
+		? bch2_btree_bit_mod(trans, BTREE_ID_lru,
+				     lru_pos(lru_id, dev_bucket, time), set)
+		: 0;
 }
 
 int bch2_lru_del(struct btree_trans *trans, u16 lru_id, u64 dev_bucket, u64 time)

fs/bcachefs/lru.h

@@ -5,13 +5,6 @@
 #define LRU_TIME_BITS	48
 #define LRU_TIME_MAX	((1ULL << LRU_TIME_BITS) - 1)
 
-static inline struct bpos lru_pos(u16 lru_id, u64 dev_bucket, u64 time)
-{
-	EBUG_ON(time > LRU_TIME_MAX);
-
-	return POS(((u64) lru_id << LRU_TIME_BITS)|time, dev_bucket);
-}
-
 static inline u64 lru_pos_id(struct bpos pos)
 {
 	return pos.inode >> LRU_TIME_BITS;
@@ -22,6 +15,18 @@ static inline u64 lru_pos_time(struct bpos pos)
 	return pos.inode & ~(~0ULL << LRU_TIME_BITS);
 }
 
+static inline struct bpos lru_pos(u16 lru_id, u64 dev_bucket, u64 time)
+{
+	struct bpos pos = POS(((u64) lru_id << LRU_TIME_BITS)|time, dev_bucket);
+
+	EBUG_ON(time > LRU_TIME_MAX);
+	EBUG_ON(lru_pos_id(pos) != lru_id);
+	EBUG_ON(lru_pos_time(pos) != time);
+	EBUG_ON(pos.offset != dev_bucket);
+
+	return pos;
+}
+
 #define BCH_LRU_TYPES()		\
 	x(read)			\
 	x(fragmentation)