1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or https://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright (c) 2016, Intel Corporation.
23 * Copyright (c) 2020 by Lawrence Livermore National Security, LLC.
24 */
25
26#ifndef _SYS_VDEV_DRAID_H
27#define	_SYS_VDEV_DRAID_H
28
29#include <sys/types.h>
30#include <sys/abd.h>
31#include <sys/nvpair.h>
32#include <sys/zio.h>
33#include <sys/vdev_impl.h>
34#include <sys/vdev_raidz_impl.h>
35#include <sys/vdev.h>
36
37#ifdef  __cplusplus
38extern "C" {
39#endif
40
41/*
42 * Constants required to generate and use dRAID permutations.
43 */
44#define	VDEV_DRAID_SEED			0xd7a1d5eed
45#define	VDEV_DRAID_MAX_MAPS		254
46#define	VDEV_DRAID_ROWSHIFT		SPA_MAXBLOCKSHIFT
47#define	VDEV_DRAID_ROWHEIGHT		(1ULL << VDEV_DRAID_ROWSHIFT)
48#define	VDEV_DRAID_REFLOW_RESERVE	(2 * VDEV_DRAID_ROWHEIGHT)
49
50/*
51 * dRAID permutation map.
52 */
53typedef struct draid_map {
54	uint64_t dm_children;	/* # of permutation columns */
55	uint64_t dm_nperms;	/* # of permutation rows */
56	uint64_t dm_seed;	/* dRAID map seed */
57	uint64_t dm_checksum;	/* Checksum of generated map */
58	uint8_t *dm_perms;	/* base permutation array */
59} draid_map_t;
60
61/*
62 * dRAID configuration.
63 */
64typedef struct vdev_draid_config {
65	/*
66	 * Values read from the dRAID nvlist configuration.
67	 */
68	uint64_t vdc_ndata;		/* # of data devices in group */
69	uint64_t vdc_nparity;		/* # of parity devices in group */
70	uint64_t vdc_nspares;		/* # of distributed spares */
71	uint64_t vdc_children;		/* # of children */
72	uint64_t vdc_ngroups;		/* # groups per slice */
73
74	/*
75	 * Immutable derived constants.
76	 */
77	uint8_t *vdc_perms;		/* permutation array */
78	uint64_t vdc_nperms;		/* # of permutations */
79	uint64_t vdc_groupwidth;	/* = data + parity */
80	uint64_t vdc_ndisks;		/* = children - spares */
81	uint64_t vdc_groupsz;		/* = groupwidth * DRAID_ROWSIZE */
82	uint64_t vdc_devslicesz;	/* = (groupsz * groups) / ndisks */
83} vdev_draid_config_t;
84
85/*
86 * Functions for handling dRAID permutation maps.
87 */
88extern uint64_t vdev_draid_rand(uint64_t *);
89extern int vdev_draid_lookup_map(uint64_t, const draid_map_t **);
90extern int vdev_draid_generate_perms(const draid_map_t *, uint8_t **);
91
92/*
93 * General dRAID support functions.
94 */
95extern boolean_t vdev_draid_readable(vdev_t *, uint64_t);
96extern boolean_t vdev_draid_missing(vdev_t *, uint64_t, uint64_t, uint64_t);
97extern uint64_t vdev_draid_asize_to_psize(vdev_t *, uint64_t);
98extern void vdev_draid_map_alloc_empty(zio_t *, struct raidz_row *);
99extern int vdev_draid_map_verify_empty(zio_t *, struct raidz_row *);
100extern nvlist_t *vdev_draid_read_config_spare(vdev_t *);
101
102/* Functions for dRAID distributed spares. */
103extern vdev_t *vdev_draid_spare_get_child(vdev_t *, uint64_t);
104extern vdev_t *vdev_draid_spare_get_parent(vdev_t *);
105extern int vdev_draid_spare_create(nvlist_t *, vdev_t *, uint64_t *, uint64_t);
106
107#ifdef  __cplusplus
108}
109#endif
110
111#endif /* _SYS_VDEV_DRAID_H */
112