diff --git a/reftable/block.c b/reftable/block.c
index a425dd7abf..20712be7ee 100644
--- a/reftable/block.c
+++ b/reftable/block.c
@@ -381,11 +381,16 @@ static uint32_t block_restart_offset(const struct reftable_block *b, size_t idx)
 	return reftable_get_be24(b->block_data.data + b->restart_off + 3 * idx);
 }
 
-void block_iter_seek_start(struct block_iter *it, const struct reftable_block *block)
+void block_iter_init(struct block_iter *it, const struct reftable_block *block)
 {
 	it->block = block;
+	block_iter_seek_start(it);
+}
+
+void block_iter_seek_start(struct block_iter *it)
+{
 	reftable_buf_reset(&it->last_key);
-	it->next_off = block->header_off + 4;
+	it->next_off = it->block->header_off + 4;
 }
 
 struct restart_needle_less_args {
@@ -473,12 +478,11 @@ void block_iter_close(struct block_iter *it)
 	reftable_buf_release(&it->scratch);
 }
 
-int block_iter_seek_key(struct block_iter *it, const struct reftable_block *block,
-			struct reftable_buf *want)
+int block_iter_seek_key(struct block_iter *it, struct reftable_buf *want)
 {
 	struct restart_needle_less_args args = {
 		.needle = *want,
-		.block = block,
+		.block = it->block,
 	};
 	struct reftable_record rec;
 	int err = 0;
@@ -496,7 +500,7 @@ int block_iter_seek_key(struct block_iter *it, const struct reftable_block *bloc
 	 * restart point. While that works alright, we would end up scanning
 	 * too many record.
 	 */
-	i = binsearch(block->restart_count, &restart_needle_less, &args);
+	i = binsearch(it->block->restart_count, &restart_needle_less, &args);
 	if (args.error) {
 		err = REFTABLE_FORMAT_ERROR;
 		goto done;
@@ -521,12 +525,11 @@ int block_iter_seek_key(struct block_iter *it, const struct reftable_block *bloc
 	 *     starting from the preceding restart point.
 	 */
 	if (i > 0)
-		it->next_off = block_restart_offset(block, i - 1);
+		it->next_off = block_restart_offset(it->block, i - 1);
 	else
-		it->next_off = block->header_off + 4;
-	it->block = block;
+		it->next_off = it->block->header_off + 4;
 
-	err = reftable_record_init(&rec, reftable_block_type(block));
+	err = reftable_record_init(&rec, reftable_block_type(it->block));
 	if (err < 0)
 		goto done;
 
diff --git a/reftable/block.h b/reftable/block.h
index 268d5a1e00..1bfd44f56a 100644
--- a/reftable/block.h
+++ b/reftable/block.h
@@ -79,12 +79,23 @@ struct block_iter {
 	.scratch = REFTABLE_BUF_INIT, \
 }
 
-/* Position `it` at start of the block */
-void block_iter_seek_start(struct block_iter *it, const struct reftable_block *block);
+/*
+ * Initialize the block iterator with the given block. The iterator will be
+ * positioned at the first record contained in the block. The block must remain
+ * valid until the end of the iterator's lifetime. It is valid to re-initialize
+ * iterators multiple times.
+ */
+void block_iter_init(struct block_iter *it, const struct reftable_block *block);
 
-/* Position `it` to the `want` key in the block */
-int block_iter_seek_key(struct block_iter *it, const struct reftable_block *block,
-			struct reftable_buf *want);
+/* Position the initialized iterator at the first record of its block. */
+void block_iter_seek_start(struct block_iter *it);
+
+/*
+ * Position the initialized iterator at the desired record key. It is not an
+ * error in case the record cannot be found. If so, a subsequent call to
+ * `block_iter_next()` will indicate that the iterator is exhausted.
+ */
+int block_iter_seek_key(struct block_iter *it, struct reftable_buf *want);
 
 /* return < 0 for error, 0 for OK, > 0 for EOF. */
 int block_iter_next(struct block_iter *it, struct reftable_record *rec);
diff --git a/reftable/iter.c b/reftable/iter.c
index 9ce675510c..a79c90d9ba 100644
--- a/reftable/iter.c
+++ b/reftable/iter.c
@@ -139,7 +139,7 @@ static int indexed_table_ref_iter_next_block(struct indexed_table_ref_iter *it)
 		/* indexed block does not exist. */
 		return REFTABLE_FORMAT_ERROR;
 	}
-	block_iter_seek_start(&it->cur, &it->block);
+	block_iter_init(&it->cur, &it->block);
 	return 0;
 }
 
diff --git a/reftable/table.c b/reftable/table.c
index ef1f33c92f..50ffad7edc 100644
--- a/reftable/table.c
+++ b/reftable/table.c
@@ -208,7 +208,7 @@ static int table_iter_next_block(struct table_iter *ti)
 
 	ti->block_off = next_block_off;
 	ti->is_finished = 0;
-	block_iter_seek_start(&ti->bi, &ti->block);
+	block_iter_init(&ti->bi, &ti->block);
 
 	return 0;
 }
@@ -256,7 +256,7 @@ static int table_iter_seek_to(struct table_iter *ti, uint64_t off, uint8_t typ)
 
 	ti->typ = reftable_block_type(&ti->block);
 	ti->block_off = off;
-	block_iter_seek_start(&ti->bi, &ti->block);
+	block_iter_init(&ti->bi, &ti->block);
 	ti->is_finished = 0;
 	return 0;
 }
@@ -349,7 +349,8 @@ static int table_iter_seek_linear(struct table_iter *ti,
 	 * the wanted key inside of it. If the block does not contain our key
 	 * we know that the corresponding record does not exist.
 	 */
-	err = block_iter_seek_key(&ti->bi, &ti->block, &want_key);
+	block_iter_init(&ti->bi, &ti->block);
+	err = block_iter_seek_key(&ti->bi, &want_key);
 	if (err < 0)
 		goto done;
 	err = 0;
@@ -417,7 +418,9 @@ static int table_iter_seek_indexed(struct table_iter *ti,
 		if (err != 0)
 			goto done;
 
-		err = block_iter_seek_key(&ti->bi, &ti->block, &want_index.u.idx.last_key);
+		block_iter_init(&ti->bi, &ti->block);
+
+		err = block_iter_seek_key(&ti->bi, &want_index.u.idx.last_key);
 		if (err < 0)
 			goto done;
 
diff --git a/t/unit-tests/t-reftable-block.c b/t/unit-tests/t-reftable-block.c
index e36ed7ac57..9f91d697f6 100644
--- a/t/unit-tests/t-reftable-block.c
+++ b/t/unit-tests/t-reftable-block.c
@@ -66,7 +66,7 @@ static void t_ref_block_read_write(void)
 	block_source_from_buf(&source ,&block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -79,10 +79,9 @@ static void t_ref_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_record_key(&recs[i], &want);
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -91,7 +90,7 @@ static void t_ref_block_read_write(void)
 		check(reftable_record_equal(&recs[i], &rec, REFTABLE_HASH_SIZE_SHA1));
 
 		want.len--;
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -156,7 +155,7 @@ static void t_log_block_read_write(void)
 	block_source_from_buf(&source, &block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -169,11 +168,10 @@ static void t_log_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_buf_reset(&want);
 		check(!reftable_buf_addstr(&want, recs[i].u.log.refname));
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -182,7 +180,7 @@ static void t_log_block_read_write(void)
 		check(reftable_record_equal(&recs[i], &rec, REFTABLE_HASH_SIZE_SHA1));
 
 		want.len--;
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -249,7 +247,7 @@ static void t_obj_block_read_write(void)
 	block_source_from_buf(&source, &block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -262,10 +260,9 @@ static void t_obj_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_record_key(&recs[i], &want);
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -334,7 +331,7 @@ static void t_index_block_read_write(void)
 	block_source_from_buf(&source, &block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -347,10 +344,9 @@ static void t_index_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_record_key(&recs[i], &want);
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -359,7 +355,7 @@ static void t_index_block_read_write(void)
 		check(reftable_record_equal(&recs[i], &rec, REFTABLE_HASH_SIZE_SHA1));
 
 		want.len--;
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);