dm-vdo/indexer/open-chapter.c

21  * records are stored in an array in the order they arrive. Additionally, a reference to each
24  * records is 1-based so that record number 0 can be used to indicate an unused hash slot.
26  * Deleted records are marked with a flag rather than actually removed to simplify hash table
29  * power of two that is greater than the number of records to be indexed, guaranteeing that hash
30  * insertion cannot fail, and that there are sufficient flags for all records.
32  * Once any open chapter zone fills its available space, the chapter is closed. The records from
34  * Empty or deleted records are replaced by copies of a valid record so that the record pages only
35  * contain valid records. The chapter then constructs a delta index which maps each record name to
39  * When the index is saved, the open chapter records are saved in a single array, once again
41  * different number of zones than previously, so the records must be parcelled out to their new
43  * records than it has space. In this case, the latest records for that zone will be discarded.
80 					    &open_chapter->records);
95 	memset(open_chapter->records, 0, records_size(open_chapter));
122 		record = &open_chapter->records[record_number];
148 		*metadata = open_chapter->records[record_number].data;
172 	record = &open_chapter->records[record_number];
197 		vdo_free(open_chapter->records);
212 	unsigned int records = 0;
220 	 * the chapter zone if it was closed early, and also to replace any deleted records. The
228 			fill_record = &zone->records[zone->size];
236 	for (records = 0; records < records_per_chapter; records++) {
237 		struct uds_volume_record *record = &collated_records[records];
241 		record_index = 1 + (records / zone_count);
242 		page_number = records / records_per_page;
243 		open_chapter = chapter_zones[records % zone_count];
252 		*record = open_chapter->records[record_index];
333 			record = &open_chapter->records[record_index];
364 	 * Track which zones cannot accept any more records. If the open chapter had a different
365 	 * number of zones previously, some new zones may have more records than they have space
366 	 * for. These overflow records will be discarded.