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 38 extern "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 */ 53 typedef 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 */ 64 typedef 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 */ 88 extern uint64_t vdev_draid_rand(uint64_t *); 89 extern int vdev_draid_lookup_map(uint64_t, const draid_map_t **); 90 extern int vdev_draid_generate_perms(const draid_map_t *, uint8_t **); 91 92 /* 93 * General dRAID support functions. 94 */ 95 extern boolean_t vdev_draid_readable(vdev_t *, uint64_t); 96 extern boolean_t vdev_draid_missing(vdev_t *, uint64_t, uint64_t, uint64_t); 97 extern uint64_t vdev_draid_asize_to_psize(vdev_t *, uint64_t); 98 extern void vdev_draid_map_alloc_empty(zio_t *, struct raidz_row *); 99 extern int vdev_draid_map_verify_empty(zio_t *, struct raidz_row *); 100 extern nvlist_t *vdev_draid_read_config_spare(vdev_t *); 101 102 /* Functions for dRAID distributed spares. */ 103 extern vdev_t *vdev_draid_spare_get_child(vdev_t *, uint64_t); 104 extern vdev_t *vdev_draid_spare_get_parent(vdev_t *); 105 extern 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