1 files changed, 83 insertions, 0 deletions
diff --git a/drivers/md/dm-vdo/indexer/index.h b/drivers/md/dm-vdo/indexer/index.h
new file mode 100644
index 000000000000..edabb239548e
--- /dev/null
+++ b/drivers/md/dm-vdo/indexer/index.h
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2023 Red Hat
+ */
+
+#ifndef UDS_INDEX_H
+#define UDS_INDEX_H
+
+#include "index-layout.h"
+#include "index-session.h"
+#include "open-chapter.h"
+#include "volume.h"
+#include "volume-index.h"
+
+/*
+ * The index is a high-level structure which represents the totality of the UDS index. It manages
+ * the queues for incoming requests and dispatches them to the appropriate sub-components like the
+ * volume or the volume index. It also manages administrative tasks such as saving and loading the
+ * index.
+ *
+ * The index is divided into a number of independent zones and assigns each request to a zone based
+ * on its name. Most sub-components are similarly divided into zones as well so that requests in
+ * each zone usually operate without interference or coordination between zones.
+ */
+
+typedef void (*index_callback_fn)(struct uds_request *request);
+
+struct index_zone {
+	struct uds_index *index;
+	struct open_chapter_zone *open_chapter;
+	struct open_chapter_zone *writing_chapter;
+	u64 oldest_virtual_chapter;
+	u64 newest_virtual_chapter;
+	unsigned int id;
+};
+
+struct uds_index {
+	bool has_saved_open_chapter;
+	bool need_to_save;
+	struct index_load_context *load_context;
+	struct index_layout *layout;
+	struct volume_index *volume_index;
+	struct volume *volume;
+	unsigned int zone_count;
+	struct index_zone **zones;
+
+	u64 oldest_virtual_chapter;
+	u64 newest_virtual_chapter;
+
+	u64 last_save;
+	u64 prev_save;
+	struct chapter_writer *chapter_writer;
+
+	index_callback_fn callback;
+	struct uds_request_queue *triage_queue;
+	struct uds_request_queue *zone_queues[];
+};
+
+enum request_stage {
+	STAGE_TRIAGE,
+	STAGE_INDEX,
+	STAGE_MESSAGE,
+};
+
+int __must_check uds_make_index(struct uds_configuration *config,
+				enum uds_open_index_type open_type,
+				struct index_load_context *load_context,
+				index_callback_fn callback, struct uds_index **new_index);
+
+int __must_check uds_save_index(struct uds_index *index);
+
+void uds_free_index(struct uds_index *index);
+
+int __must_check uds_replace_index_storage(struct uds_index *index,
+					   struct block_device *bdev);
+
+void uds_get_index_stats(struct uds_index *index, struct uds_index_stats *counters);
+
+void uds_enqueue_request(struct uds_request *request, enum request_stage stage);
+
+void uds_wait_for_idle_index(struct uds_index *index);
+
+#endif /* UDS_INDEX_H */