1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * This file and its contents are supplied under the terms of the 4 * Common Development and Distribution License ("CDDL"), version 1.0. 5 * You may only use this file in accordance with the terms of version 6 * 1.0 of the CDDL. 7 * 8 * A full copy of the text of the CDDL should have accompanied this 9 * source. A copy of the CDDL is also available via the Internet at 10 * https://opensource.org/license/CDDL-1.0. 11 */ 12 /* 13 * Copyright (c) 2016, Intel Corporation. 14 * Copyright (c) 2020 by Lawrence Livermore National Security, LLC. 15 */ 16 17 #ifndef _SYS_VDEV_DRAID_H 18 #define _SYS_VDEV_DRAID_H 19 20 #include <sys/types.h> 21 #include <sys/abd.h> 22 #include <sys/nvpair.h> 23 #include <sys/zio.h> 24 #include <sys/vdev_impl.h> 25 #include <sys/vdev_raidz_impl.h> 26 #include <sys/vdev.h> 27 28 #ifdef __cplusplus 29 extern "C" { 30 #endif 31 32 /* 33 * Constants required to generate and use dRAID permutations. 34 */ 35 #define VDEV_DRAID_SEED 0xd7a1d5eed 36 #define VDEV_DRAID_MAX_MAPS 254 37 #define VDEV_DRAID_ROWSHIFT SPA_MAXBLOCKSHIFT 38 #define VDEV_DRAID_ROWHEIGHT (1ULL << VDEV_DRAID_ROWSHIFT) 39 #define VDEV_DRAID_REFLOW_RESERVE (2 * VDEV_DRAID_ROWHEIGHT) 40 41 /* 42 * dRAID permutation map. 43 */ 44 typedef struct draid_map { 45 uint64_t dm_children; /* # of permutation columns */ 46 uint64_t dm_nperms; /* # of permutation rows */ 47 uint64_t dm_seed; /* dRAID map seed */ 48 uint64_t dm_checksum; /* Checksum of generated map */ 49 uint8_t *dm_perms; /* base permutation array */ 50 } draid_map_t; 51 52 /* 53 * dRAID configuration. 54 */ 55 typedef struct vdev_draid_config { 56 /* 57 * Values read from the dRAID nvlist configuration. 58 */ 59 uint64_t vdc_ndata; /* # of data devices in group */ 60 uint64_t vdc_nparity; /* # of parity devices in group */ 61 uint64_t vdc_nspares; /* # of distributed spares in slice */ 62 uint64_t vdc_children; /* # of children */ 63 uint64_t vdc_ngroups; /* # groups per slice */ 64 uint64_t vdc_width; /* # multiple of children */ 65 66 /* 67 * Immutable derived constants. 68 */ 69 uint8_t *vdc_perms; /* permutation array */ 70 uint64_t vdc_nperms; /* # of permutations */ 71 uint64_t vdc_groupwidth; /* = data + parity */ 72 uint64_t vdc_ndisks; /* = children - spares */ 73 uint64_t vdc_groupsz; /* = groupwidth * DRAID_ROWSIZE */ 74 uint64_t vdc_devslicesz; /* = (groupsz * groups) / ndisks */ 75 } vdev_draid_config_t; 76 77 /* 78 * Functions for handling dRAID permutation maps. 79 */ 80 extern uint64_t vdev_draid_rand(uint64_t *); 81 extern int vdev_draid_lookup_map(uint64_t, const draid_map_t **); 82 extern int vdev_draid_generate_perms(const draid_map_t *, uint8_t **); 83 84 /* 85 * General dRAID support functions. 86 */ 87 extern boolean_t vdev_draid_readable(vdev_t *, uint64_t); 88 extern boolean_t vdev_draid_missing(vdev_t *, uint64_t, uint64_t, uint64_t); 89 extern uint64_t vdev_draid_asize_to_psize(vdev_t *, uint64_t, uint64_t); 90 extern void vdev_draid_map_alloc_empty(zio_t *, struct raidz_row *); 91 extern int vdev_draid_map_verify_empty(zio_t *, struct raidz_row *); 92 extern nvlist_t *vdev_draid_read_config_spare(vdev_t *); 93 94 /* Functions for dRAID distributed spares. */ 95 extern vdev_t *vdev_draid_spare_get_child(vdev_t *, uint64_t); 96 extern vdev_t *vdev_draid_spare_get_parent(vdev_t *); 97 extern int vdev_draid_spare_create(nvlist_t *, vdev_t *, uint64_t *, uint64_t *, 98 uint64_t); 99 extern boolean_t vdev_draid_fail_domain_allowed(vdev_t *); 100 101 #ifdef __cplusplus 102 } 103 #endif 104 105 #endif /* _SYS_VDEV_DRAID_H */ 106