1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _RAID0_H
3#define _RAID0_H
4
5struct strip_zone {
6	sector_t zone_end;	/* Start of the next zone (in sectors) */
7	sector_t dev_start;	/* Zone offset in real dev (in sectors) */
8	int	 nb_dev;	/* # of devices attached to the zone */
9	int	 disk_shift;	/* start disk for the original layout */
10};
11
12/* Linux 3.14 (20d0189b101) made an unintended change to
13 * the RAID0 layout for multi-zone arrays (where devices aren't all
14 * the same size.
15 * RAID0_ORIG_LAYOUT restores the original layout
16 * RAID0_ALT_MULTIZONE_LAYOUT uses the altered layout
17 * The layouts are identical when there is only one zone (all
18 * devices the same size).
19 */
20
21enum r0layout {
22	RAID0_ORIG_LAYOUT = 1,
23	RAID0_ALT_MULTIZONE_LAYOUT = 2,
24};
25struct r0conf {
26	struct strip_zone	*strip_zone;
27	struct md_rdev		**devlist; /* lists of rdevs, pointed to
28					    * by strip_zone->dev */
29	int			nr_strip_zones;
30	enum r0layout		layout;
31};
32
33#endif
34