xref: /linux/drivers/md/dm-vdo/indexer/open-chapter.h (revision 79790b6818e96c58fe2bffee1b418c16e64e7b80)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright 2023 Red Hat
4  */
5 
6 #ifndef UDS_OPEN_CHAPTER_H
7 #define UDS_OPEN_CHAPTER_H
8 
9 #include "chapter-index.h"
10 #include "geometry.h"
11 #include "index.h"
12 #include "volume.h"
13 
14 /*
15  * The open chapter tracks the newest records in memory. Like the index as a whole, each open
16  * chapter is divided into a number of independent zones which are interleaved when the chapter is
17  * committed to the volume.
18  */
19 
20 enum {
21 	OPEN_CHAPTER_RECORD_NUMBER_BITS = 23,
22 };
23 
24 struct open_chapter_zone_slot {
25 	/* If non-zero, the record number addressed by this hash slot */
26 	unsigned int record_number : OPEN_CHAPTER_RECORD_NUMBER_BITS;
27 	/* If true, the record at the index of this hash slot was deleted */
28 	bool deleted : 1;
29 } __packed;
30 
31 struct open_chapter_zone {
32 	/* The maximum number of records that can be stored */
33 	unsigned int capacity;
34 	/* The number of records stored */
35 	unsigned int size;
36 	/* The number of deleted records */
37 	unsigned int deletions;
38 	/* Array of chunk records, 1-based */
39 	struct uds_volume_record *records;
40 	/* The number of slots in the hash table */
41 	unsigned int slot_count;
42 	/* The hash table slots, referencing virtual record numbers */
43 	struct open_chapter_zone_slot slots[];
44 };
45 
46 int __must_check uds_make_open_chapter(const struct index_geometry *geometry,
47 				       unsigned int zone_count,
48 				       struct open_chapter_zone **open_chapter_ptr);
49 
50 void uds_reset_open_chapter(struct open_chapter_zone *open_chapter);
51 
52 void uds_search_open_chapter(struct open_chapter_zone *open_chapter,
53 			     const struct uds_record_name *name,
54 			     struct uds_record_data *metadata, bool *found);
55 
56 int __must_check uds_put_open_chapter(struct open_chapter_zone *open_chapter,
57 				      const struct uds_record_name *name,
58 				      const struct uds_record_data *metadata);
59 
60 void uds_remove_from_open_chapter(struct open_chapter_zone *open_chapter,
61 				  const struct uds_record_name *name);
62 
63 void uds_free_open_chapter(struct open_chapter_zone *open_chapter);
64 
65 int __must_check uds_close_open_chapter(struct open_chapter_zone **chapter_zones,
66 					unsigned int zone_count, struct volume *volume,
67 					struct open_chapter_index *chapter_index,
68 					struct uds_volume_record *collated_records,
69 					u64 virtual_chapter_number);
70 
71 int __must_check uds_save_open_chapter(struct uds_index *index,
72 				       struct buffered_writer *writer);
73 
74 int __must_check uds_load_open_chapter(struct uds_index *index,
75 				       struct buffered_reader *reader);
76 
77 u64 uds_compute_saved_open_chapter_size(struct index_geometry *geometry);
78 
79 #endif /* UDS_OPEN_CHAPTER_H */
80