zfs/include/sys/vdev_draid.h

112 lines
3.5 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2016, Intel Corporation.
* Copyright (c) 2020 by Lawrence Livermore National Security, LLC.
*/
#ifndef _SYS_VDEV_DRAID_H
#define _SYS_VDEV_DRAID_H
#include <sys/types.h>
#include <sys/abd.h>
#include <sys/nvpair.h>
#include <sys/zio.h>
#include <sys/vdev_impl.h>
#include <sys/vdev_raidz_impl.h>
#include <sys/vdev.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* Constants required to generate and use dRAID permutations.
*/
#define VDEV_DRAID_SEED 0xd7a1d5eed
#define VDEV_DRAID_MAX_MAPS 254
#define VDEV_DRAID_ROWSHIFT SPA_MAXBLOCKSHIFT
#define VDEV_DRAID_ROWHEIGHT (1ULL << VDEV_DRAID_ROWSHIFT)
#define VDEV_DRAID_REFLOW_RESERVE (2 * VDEV_DRAID_ROWHEIGHT)
/*
* dRAID permutation map.
*/
typedef struct draid_map {
uint64_t dm_children; /* # of permutation columns */
uint64_t dm_nperms; /* # of permutation rows */
uint64_t dm_seed; /* dRAID map seed */
uint64_t dm_checksum; /* Checksum of generated map */
uint8_t *dm_perms; /* base permutation array */
} draid_map_t;
/*
* dRAID configuration.
*/
typedef struct vdev_draid_config {
/*
* Values read from the dRAID nvlist configuration.
*/
uint64_t vdc_ndata; /* # of data devices in group */
uint64_t vdc_nparity; /* # of parity devices in group */
uint64_t vdc_nspares; /* # of distributed spares */
uint64_t vdc_children; /* # of children */
uint64_t vdc_ngroups; /* # groups per slice */
/*
* Immutable derived constants.
*/
uint8_t *vdc_perms; /* permutation array */
uint64_t vdc_nperms; /* # of permutations */
uint64_t vdc_groupwidth; /* = data + parity */
uint64_t vdc_ndisks; /* = children - spares */
uint64_t vdc_groupsz; /* = groupwidth * DRAID_ROWSIZE */
uint64_t vdc_devslicesz; /* = (groupsz * groups) / ndisks */
} vdev_draid_config_t;
/*
* Functions for handling dRAID permutation maps.
*/
extern uint64_t vdev_draid_rand(uint64_t *);
extern int vdev_draid_lookup_map(uint64_t, const draid_map_t **);
extern int vdev_draid_generate_perms(const draid_map_t *, uint8_t **);
/*
* General dRAID support functions.
*/
extern boolean_t vdev_draid_readable(vdev_t *, uint64_t);
extern boolean_t vdev_draid_missing(vdev_t *, uint64_t, uint64_t, uint64_t);
extern uint64_t vdev_draid_asize_to_psize(vdev_t *, uint64_t);
extern void vdev_draid_map_alloc_empty(zio_t *, struct raidz_row *);
extern int vdev_draid_map_verify_empty(zio_t *, struct raidz_row *);
extern nvlist_t *vdev_draid_read_config_spare(vdev_t *);
/* Functions for dRAID distributed spares. */
extern vdev_t *vdev_draid_spare_get_child(vdev_t *, uint64_t);
extern vdev_t *vdev_draid_spare_get_parent(vdev_t *);
extern int vdev_draid_spare_create(nvlist_t *, vdev_t *, uint64_t *, uint64_t);
#ifdef __cplusplus
}
#endif
#endif /* _SYS_VDEV_DRAID_H */