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 */ 51