blob: 0df64e5593bc0e18d09d1c000c975c9c3407057d [file] [log] [blame]
Angel Pons32859fc2020-04-02 23:48:27 +02001/* SPDX-License-Identifier: GPL-2.0-only */
Aaron Durbincd0bc982016-11-19 12:36:09 -06002
3#ifndef REGION_FILE_H
4#define REGION_FILE_H
5
6#include <commonlib/region.h>
7#include <stdint.h>
8
9/*
10 * A region file is an abstraction to allow appending updates in a
11 * region_device where the data returned is the most recently written
12 * data. It is block based with a 16 byte granularity. So if you write
13 * 2 bytes into the file the data returned in the region_device would
14 * have 16 bytes allocated for the latest update. Additionally, the
15 * current maximum file size allowed is 1MiB - 48 bytes. See comments
16 * in C implementation file for further details.
17 */
18
19struct region_file;
20
21/*
22 * Initialize a region file associated with a provided region device.
23 * Returns < 0 on error, 0 on success.
24 */
25int region_file_init(struct region_file *f, const struct region_device *p);
26
27/*
28 * Initialize region device object associated with latest update of file data.
29 * Returns < 0 on error, 0 on success.
30 */
31int region_file_data(const struct region_file *f, struct region_device *rdev);
32
33/* Update region file with latest data. Returns < 0 on error, 0 on success. */
34int region_file_update_data(struct region_file *f, const void *buf,
35 size_t size);
36
37/* Declared here for easy object allocation. */
38struct region_file {
39 /* Region device covering file */
40 struct region_device rdev;
41 /* Metadata containing blocks of the data stream. */
42 struct region_device metadata;
43 /* Blocks forming data. */
44 uint16_t data_blocks[2];
45 /* Current slot in metadata marking end of data. */
46 int slot;
47};
48
49#endif /* REGION_FILE_H */