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 http://www.opensolaris.org/os/licensing. 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 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* 27 * Copyright (c) 2012, 2018 by Delphix. All rights reserved. 28 */ 29 30 #ifndef _SYS_SPACE_MAP_H 31 #define _SYS_SPACE_MAP_H 32 33 #include <sys/avl.h> 34 #include <sys/range_tree.h> 35 #include <sys/dmu.h> 36 37 #ifdef __cplusplus 38 extern "C" { 39 #endif 40 41 /* 42 * The size of the space map object has increased to include a histogram. 43 * The SPACE_MAP_SIZE_V0 designates the original size and is used to 44 * maintain backward compatibility. 45 */ 46 #define SPACE_MAP_SIZE_V0 (3 * sizeof (uint64_t)) 47 #define SPACE_MAP_HISTOGRAM_SIZE 32 48 49 /* 50 * The space_map_phys is the on-disk representation of the space map. 51 * Consumers of space maps should never reference any of the members of this 52 * structure directly. These members may only be updated in syncing context. 53 * 54 * Note the smp_object is no longer used but remains in the structure 55 * for backward compatibility. 56 */ 57 typedef struct space_map_phys { 58 /* object number: not needed but kept for backwards compatibility */ 59 uint64_t smp_object; 60 61 /* length of the object in bytes */ 62 uint64_t smp_length; 63 64 /* space allocated from the map */ 65 int64_t smp_alloc; 66 67 /* reserved */ 68 uint64_t smp_pad[5]; 69 70 /* 71 * The smp_histogram maintains a histogram of free regions. Each 72 * bucket, smp_histogram[i], contains the number of free regions 73 * whose size is: 74 * 2^(i+sm_shift) <= size of free region in bytes < 2^(i+sm_shift+1) 75 */ 76 uint64_t smp_histogram[SPACE_MAP_HISTOGRAM_SIZE]; 77 } space_map_phys_t; 78 79 /* 80 * The space map object defines a region of space, its size, how much is 81 * allocated, and the on-disk object that stores this information. 82 * Consumers of space maps may only access the members of this structure. 83 * 84 * Note: the space_map may not be accessed concurrently; consumers 85 * must provide external locking if required. 86 */ 87 typedef struct space_map { 88 uint64_t sm_start; /* start of map */ 89 uint64_t sm_size; /* size of map */ 90 uint8_t sm_shift; /* unit shift */ 91 objset_t *sm_os; /* objset for this map */ 92 uint64_t sm_object; /* object id for this map */ 93 uint32_t sm_blksz; /* block size for space map */ 94 dmu_buf_t *sm_dbuf; /* space_map_phys_t dbuf */ 95 space_map_phys_t *sm_phys; /* on-disk space map */ 96 } space_map_t; 97 98 /* 99 * debug entry 100 * 101 * 2 2 10 50 102 * +-----+-----+------------+----------------------------------+ 103 * | 1 0 | act | syncpass | txg (lower bits) | 104 * +-----+-----+------------+----------------------------------+ 105 * 63 62 61 60 59 50 49 0 106 * 107 * 108 * one-word entry 109 * 110 * 1 47 1 15 111 * +-----------------------------------------------------------+ 112 * | 0 | offset (sm_shift units) | type | run | 113 * +-----------------------------------------------------------+ 114 * 63 62 16 15 14 0 115 * 116 * 117 * two-word entry 118 * 119 * 2 2 36 24 120 * +-----+-----+---------------------------+-------------------+ 121 * | 1 1 | pad | run | vdev | 122 * +-----+-----+---------------------------+-------------------+ 123 * 63 62 61 60 59 24 23 0 124 * 125 * 1 63 126 * +------+----------------------------------------------------+ 127 * | type | offset | 128 * +------+----------------------------------------------------+ 129 * 63 62 0 130 * 131 * Note that a two-word entry will not strandle a block boundary. 132 * If necessary, the last word of a block will be padded with a 133 * debug entry (with act = syncpass = txg = 0). 134 */ 135 136 typedef enum { 137 SM_ALLOC, 138 SM_FREE 139 } maptype_t; 140 141 typedef struct space_map_entry { 142 maptype_t sme_type; 143 uint32_t sme_vdev; /* max is 2^24-1; SM_NO_VDEVID if not present */ 144 uint64_t sme_offset; /* max is 2^63-1; units of sm_shift */ 145 uint64_t sme_run; /* max is 2^36; units of sm_shift */ 146 } space_map_entry_t; 147 148 #define SM_NO_VDEVID (1 << SPA_VDEVBITS) 149 150 /* one-word entry constants */ 151 #define SM_DEBUG_PREFIX 2 152 #define SM_OFFSET_BITS 47 153 #define SM_RUN_BITS 15 154 155 /* two-word entry constants */ 156 #define SM2_PREFIX 3 157 #define SM2_OFFSET_BITS 63 158 #define SM2_RUN_BITS 36 159 160 #define SM_PREFIX_DECODE(x) BF64_DECODE(x, 62, 2) 161 #define SM_PREFIX_ENCODE(x) BF64_ENCODE(x, 62, 2) 162 163 #define SM_DEBUG_ACTION_DECODE(x) BF64_DECODE(x, 60, 2) 164 #define SM_DEBUG_ACTION_ENCODE(x) BF64_ENCODE(x, 60, 2) 165 #define SM_DEBUG_SYNCPASS_DECODE(x) BF64_DECODE(x, 50, 10) 166 #define SM_DEBUG_SYNCPASS_ENCODE(x) BF64_ENCODE(x, 50, 10) 167 #define SM_DEBUG_TXG_DECODE(x) BF64_DECODE(x, 0, 50) 168 #define SM_DEBUG_TXG_ENCODE(x) BF64_ENCODE(x, 0, 50) 169 170 #define SM_OFFSET_DECODE(x) BF64_DECODE(x, 16, SM_OFFSET_BITS) 171 #define SM_OFFSET_ENCODE(x) BF64_ENCODE(x, 16, SM_OFFSET_BITS) 172 #define SM_TYPE_DECODE(x) BF64_DECODE(x, 15, 1) 173 #define SM_TYPE_ENCODE(x) BF64_ENCODE(x, 15, 1) 174 #define SM_RUN_DECODE(x) (BF64_DECODE(x, 0, SM_RUN_BITS) + 1) 175 #define SM_RUN_ENCODE(x) BF64_ENCODE((x) - 1, 0, SM_RUN_BITS) 176 #define SM_RUN_MAX SM_RUN_DECODE(~0ULL) 177 #define SM_OFFSET_MAX SM_OFFSET_DECODE(~0ULL) 178 179 #define SM2_RUN_DECODE(x) (BF64_DECODE(x, SPA_VDEVBITS, SM2_RUN_BITS) + 1) 180 #define SM2_RUN_ENCODE(x) BF64_ENCODE((x) - 1, SPA_VDEVBITS, SM2_RUN_BITS) 181 #define SM2_VDEV_DECODE(x) BF64_DECODE(x, 0, SPA_VDEVBITS) 182 #define SM2_VDEV_ENCODE(x) BF64_ENCODE(x, 0, SPA_VDEVBITS) 183 #define SM2_TYPE_DECODE(x) BF64_DECODE(x, SM2_OFFSET_BITS, 1) 184 #define SM2_TYPE_ENCODE(x) BF64_ENCODE(x, SM2_OFFSET_BITS, 1) 185 #define SM2_OFFSET_DECODE(x) BF64_DECODE(x, 0, SM2_OFFSET_BITS) 186 #define SM2_OFFSET_ENCODE(x) BF64_ENCODE(x, 0, SM2_OFFSET_BITS) 187 #define SM2_RUN_MAX SM2_RUN_DECODE(~0ULL) 188 #define SM2_OFFSET_MAX SM2_OFFSET_DECODE(~0ULL) 189 190 boolean_t sm_entry_is_debug(uint64_t e); 191 boolean_t sm_entry_is_single_word(uint64_t e); 192 boolean_t sm_entry_is_double_word(uint64_t e); 193 194 typedef int (*sm_cb_t)(space_map_entry_t *sme, void *arg); 195 196 int space_map_load(space_map_t *sm, range_tree_t *rt, maptype_t maptype); 197 int space_map_load_length(space_map_t *sm, range_tree_t *rt, maptype_t maptype, 198 uint64_t length); 199 int space_map_iterate(space_map_t *sm, uint64_t length, 200 sm_cb_t callback, void *arg); 201 int space_map_incremental_destroy(space_map_t *sm, sm_cb_t callback, void *arg, 202 dmu_tx_t *tx); 203 204 boolean_t space_map_histogram_verify(space_map_t *sm, range_tree_t *rt); 205 void space_map_histogram_clear(space_map_t *sm); 206 void space_map_histogram_add(space_map_t *sm, range_tree_t *rt, 207 dmu_tx_t *tx); 208 209 uint64_t space_map_object(space_map_t *sm); 210 int64_t space_map_allocated(space_map_t *sm); 211 uint64_t space_map_length(space_map_t *sm); 212 213 void space_map_write(space_map_t *sm, range_tree_t *rt, maptype_t maptype, 214 uint64_t vdev_id, dmu_tx_t *tx); 215 uint64_t space_map_estimate_optimal_size(space_map_t *sm, range_tree_t *rt, 216 uint64_t vdev_id); 217 void space_map_truncate(space_map_t *sm, int blocksize, dmu_tx_t *tx); 218 uint64_t space_map_alloc(objset_t *os, int blocksize, dmu_tx_t *tx); 219 void space_map_free(space_map_t *sm, dmu_tx_t *tx); 220 void space_map_free_obj(objset_t *os, uint64_t smobj, dmu_tx_t *tx); 221 222 int space_map_open(space_map_t **smp, objset_t *os, uint64_t object, 223 uint64_t start, uint64_t size, uint8_t shift); 224 void space_map_close(space_map_t *sm); 225 226 #ifdef __cplusplus 227 } 228 #endif 229 230 #endif /* _SYS_SPACE_MAP_H */ 231