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Linux kernel mirror (for testing)
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kernel
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linux
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2#ifndef _PCACHE_SEGMENT_H
3#define _PCACHE_SEGMENT_H
4
5#include <linux/bio.h>
6#include <linux/bitfield.h>
7
8#include "pcache_internal.h"
9
10struct pcache_segment_info {
11 struct pcache_meta_header header;
12 __u32 flags;
13 __u32 next_seg;
14};
15
16#define PCACHE_SEG_INFO_FLAGS_HAS_NEXT BIT(0)
17
18#define PCACHE_SEG_INFO_FLAGS_TYPE_MASK GENMASK(4, 1)
19#define PCACHE_SEGMENT_TYPE_CACHE_DATA 1
20
21static inline bool segment_info_has_next(struct pcache_segment_info *seg_info)
22{
23 return (seg_info->flags & PCACHE_SEG_INFO_FLAGS_HAS_NEXT);
24}
25
26static inline void segment_info_set_type(struct pcache_segment_info *seg_info, u8 type)
27{
28 seg_info->flags &= ~PCACHE_SEG_INFO_FLAGS_TYPE_MASK;
29 seg_info->flags |= FIELD_PREP(PCACHE_SEG_INFO_FLAGS_TYPE_MASK, type);
30}
31
32static inline u8 segment_info_get_type(struct pcache_segment_info *seg_info)
33{
34 return FIELD_GET(PCACHE_SEG_INFO_FLAGS_TYPE_MASK, seg_info->flags);
35}
36
37struct pcache_segment_pos {
38 struct pcache_segment *segment; /* Segment associated with the position */
39 u32 off; /* Offset within the segment */
40};
41
42struct pcache_segment_init_options {
43 u8 type;
44 u32 seg_id;
45 u32 data_off;
46
47 struct pcache_segment_info *seg_info;
48};
49
50struct pcache_segment {
51 struct pcache_cache_dev *cache_dev;
52
53 void *data;
54 u32 data_size;
55 u32 seg_id;
56
57 struct pcache_segment_info *seg_info;
58};
59
60int segment_copy_to_bio(struct pcache_segment *segment,
61 u32 data_off, u32 data_len, struct bio *bio, u32 bio_off);
62int segment_copy_from_bio(struct pcache_segment *segment,
63 u32 data_off, u32 data_len, struct bio *bio, u32 bio_off);
64
65static inline void segment_pos_advance(struct pcache_segment_pos *seg_pos, u32 len)
66{
67 BUG_ON(seg_pos->off + len > seg_pos->segment->data_size);
68
69 seg_pos->off += len;
70}
71
72void pcache_segment_init(struct pcache_cache_dev *cache_dev, struct pcache_segment *segment,
73 struct pcache_segment_init_options *options);
74#endif /* _PCACHE_SEGMENT_H */