drivers/md/dm-vdo/indexer/index-page-map.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright 2023 Red Hat
   4  */
   5
   6 #ifndef UDS_INDEX_PAGE_MAP_H
   7 #define UDS_INDEX_PAGE_MAP_H
   8
   9 #include "geometry.h"
  10 #include "io-factory.h"
  11
  12 /*
  13  * The index maintains a page map which records how the chapter delta lists are distributed among
  14  * the index pages for each chapter, allowing the volume to be efficient about reading only pages
  15  * that it knows it will need.
  16  */
  17
  18 struct index_page_map {
  19         const struct index_geometry *geometry;
  20         u64 last_update;
  21         u32 entries_per_chapter;
  22         u16 *entries;
  23 };
  24
  25 int __must_check uds_make_index_page_map(const struct index_geometry *geometry,
  26                                          struct index_page_map **map_ptr);
  27
  28 void uds_free_index_page_map(struct index_page_map *map);
  29
  30 int __must_check uds_read_index_page_map(struct index_page_map *map,
  31                                          struct buffered_reader *reader);
  32
  33 int __must_check uds_write_index_page_map(struct index_page_map *map,
  34                                           struct buffered_writer *writer);
  35
  36 void uds_update_index_page_map(struct index_page_map *map, u64 virtual_chapter_number,
  37                                u32 chapter_number, u32 index_page_number,
  38                                u32 delta_list_number);
  39
  40 u32 __must_check uds_find_index_page_number(const struct index_page_map *map,
  41                                             const struct uds_record_name *name,
  42                                             u32 chapter_number);
  43
  44 void uds_get_list_number_bounds(const struct index_page_map *map, u32 chapter_number,
  45                                 u32 index_page_number, u32 *lowest_list,
  46                                 u32 *highest_list);
  47
  48 u64 uds_compute_index_page_map_save_size(const struct index_geometry *geometry);
  49
  50 #endif /* UDS_INDEX_PAGE_MAP_H */