1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * CDDL HEADER START 4 * 5 * The contents of this file are subject to the terms of the 6 * Common Development and Distribution License (the "License"). 7 * You may not use this file except in compliance with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or https://opensource.org/licenses/CDDL-1.0. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * Copyright (c) 2012, 2019 by Delphix. All rights reserved. 29 */ 30 31 #ifndef _SYS_SPACE_MAP_H 32 #define _SYS_SPACE_MAP_H 33 34 #include <sys/avl.h> 35 #include <sys/range_tree.h> 36 #include <sys/dmu.h> 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /* 43 * The size of the space map object has increased to include a histogram. 44 * The SPACE_MAP_SIZE_V0 designates the original size and is used to 45 * maintain backward compatibility. 46 */ 47 #define SPACE_MAP_SIZE_V0 (3 * sizeof (uint64_t)) 48 #define SPACE_MAP_HISTOGRAM_SIZE 32 49 50 /* 51 * The space_map_phys is the on-disk representation of the space map. 52 * Consumers of space maps should never reference any of the members of this 53 * structure directly. These members may only be updated in syncing context. 54 * 55 * Note the smp_object is no longer used but remains in the structure 56 * for backward compatibility. 57 */ 58 typedef struct space_map_phys { 59 /* object number: not needed but kept for backwards compatibility */ 60 uint64_t smp_object; 61 62 /* length of the object in bytes */ 63 uint64_t smp_length; 64 65 /* space allocated from the map */ 66 int64_t smp_alloc; 67 68 /* reserved */ 69 uint64_t smp_pad[5]; 70 71 /* 72 * The smp_histogram maintains a histogram of free regions. Each 73 * bucket, smp_histogram[i], contains the number of free regions 74 * whose size is: 75 * 2^(i+sm_shift) <= size of free region in bytes < 2^(i+sm_shift+1) 76 * 77 * Note that, if log space map feature is enabled, histograms of 78 * space maps that belong to metaslabs will take into account any 79 * unflushed changes for their metaslabs, even though the actual 80 * space map doesn't have entries for these changes. 81 */ 82 uint64_t smp_histogram[SPACE_MAP_HISTOGRAM_SIZE]; 83 } space_map_phys_t; 84 85 /* 86 * The space map object defines a region of space, its size, how much is 87 * allocated, and the on-disk object that stores this information. 88 * Consumers of space maps may only access the members of this structure. 89 * 90 * Note: the space_map may not be accessed concurrently; consumers 91 * must provide external locking if required. 92 */ 93 typedef struct space_map { 94 uint64_t sm_start; /* start of map */ 95 uint64_t sm_size; /* size of map */ 96 uint8_t sm_shift; /* unit shift */ 97 objset_t *sm_os; /* objset for this map */ 98 uint64_t sm_object; /* object id for this map */ 99 uint32_t sm_blksz; /* block size for space map */ 100 dmu_buf_t *sm_dbuf; /* space_map_phys_t dbuf */ 101 space_map_phys_t *sm_phys; /* on-disk space map */ 102 } space_map_t; 103 104 /* 105 * debug entry 106 * 107 * 2 2 10 50 108 * +-----+-----+------------+----------------------------------+ 109 * | 1 0 | act | syncpass | txg (lower bits) | 110 * +-----+-----+------------+----------------------------------+ 111 * 63 62 61 60 59 50 49 0 112 * 113 * 114 * one-word entry 115 * 116 * 1 47 1 15 117 * +-----------------------------------------------------------+ 118 * | 0 | offset (sm_shift units) | type | run | 119 * +-----------------------------------------------------------+ 120 * 63 62 16 15 14 0 121 * 122 * 123 * two-word entry 124 * 125 * 2 2 36 24 126 * +-----+-----+---------------------------+-------------------+ 127 * | 1 1 | pad | run | vdev | 128 * +-----+-----+---------------------------+-------------------+ 129 * 63 62 61 60 59 24 23 0 130 * 131 * 1 63 132 * +------+----------------------------------------------------+ 133 * | type | offset | 134 * +------+----------------------------------------------------+ 135 * 63 62 0 136 * 137 * Note that a two-word entry will not straddle a block boundary. 138 * If necessary, the last word of a block will be padded with a 139 * debug entry (with act = syncpass = txg = 0). 140 */ 141 142 typedef enum { 143 SM_ALLOC, 144 SM_FREE 145 } maptype_t; 146 147 typedef struct space_map_entry { 148 maptype_t sme_type; 149 uint32_t sme_vdev; /* max is 2^24-1; SM_NO_VDEVID if not present */ 150 uint64_t sme_offset; /* max is 2^63-1; units of sm_shift */ 151 uint64_t sme_run; /* max is 2^36; units of sm_shift */ 152 153 /* 154 * The following fields are not part of the actual space map entry 155 * on-disk and they are populated with the values from the debug 156 * entry most recently visited starting from the beginning to the 157 * end of the space map. 158 */ 159 uint64_t sme_txg; 160 uint64_t sme_sync_pass; 161 } space_map_entry_t; 162 163 #define SM_NO_VDEVID (1 << SPA_VDEVBITS) 164 165 /* one-word entry constants */ 166 #define SM_DEBUG_PREFIX 2 167 #define SM_OFFSET_BITS 47 168 #define SM_RUN_BITS 15 169 170 /* two-word entry constants */ 171 #define SM2_PREFIX 3 172 #define SM2_OFFSET_BITS 63 173 #define SM2_RUN_BITS 36 174 175 #define SM_PREFIX_DECODE(x) BF64_DECODE(x, 62, 2) 176 #define SM_PREFIX_ENCODE(x) BF64_ENCODE(x, 62, 2) 177 178 #define SM_DEBUG_ACTION_DECODE(x) BF64_DECODE(x, 60, 2) 179 #define SM_DEBUG_ACTION_ENCODE(x) BF64_ENCODE(x, 60, 2) 180 #define SM_DEBUG_SYNCPASS_DECODE(x) BF64_DECODE(x, 50, 10) 181 #define SM_DEBUG_SYNCPASS_ENCODE(x) BF64_ENCODE(x, 50, 10) 182 #define SM_DEBUG_TXG_DECODE(x) BF64_DECODE(x, 0, 50) 183 #define SM_DEBUG_TXG_ENCODE(x) BF64_ENCODE(x, 0, 50) 184 185 #define SM_OFFSET_DECODE(x) BF64_DECODE(x, 16, SM_OFFSET_BITS) 186 #define SM_OFFSET_ENCODE(x) BF64_ENCODE(x, 16, SM_OFFSET_BITS) 187 #define SM_TYPE_DECODE(x) BF64_DECODE(x, 15, 1) 188 #define SM_TYPE_ENCODE(x) BF64_ENCODE(x, 15, 1) 189 #define SM_RUN_DECODE(x) (BF64_DECODE(x, 0, SM_RUN_BITS) + 1) 190 #define SM_RUN_ENCODE(x) BF64_ENCODE((x) - 1, 0, SM_RUN_BITS) 191 #define SM_RUN_MAX SM_RUN_DECODE(~0ULL) 192 #define SM_OFFSET_MAX SM_OFFSET_DECODE(~0ULL) 193 194 #define SM2_RUN_DECODE(x) (BF64_DECODE(x, SPA_VDEVBITS, SM2_RUN_BITS) + 1) 195 #define SM2_RUN_ENCODE(x) BF64_ENCODE((x) - 1, SPA_VDEVBITS, SM2_RUN_BITS) 196 #define SM2_VDEV_DECODE(x) BF64_DECODE(x, 0, SPA_VDEVBITS) 197 #define SM2_VDEV_ENCODE(x) BF64_ENCODE(x, 0, SPA_VDEVBITS) 198 #define SM2_TYPE_DECODE(x) BF64_DECODE(x, SM2_OFFSET_BITS, 1) 199 #define SM2_TYPE_ENCODE(x) BF64_ENCODE(x, SM2_OFFSET_BITS, 1) 200 #define SM2_OFFSET_DECODE(x) BF64_DECODE(x, 0, SM2_OFFSET_BITS) 201 #define SM2_OFFSET_ENCODE(x) BF64_ENCODE(x, 0, SM2_OFFSET_BITS) 202 #define SM2_RUN_MAX SM2_RUN_DECODE(~0ULL) 203 #define SM2_OFFSET_MAX SM2_OFFSET_DECODE(~0ULL) 204 205 boolean_t sm_entry_is_debug(uint64_t e); 206 boolean_t sm_entry_is_single_word(uint64_t e); 207 boolean_t sm_entry_is_double_word(uint64_t e); 208 209 typedef int (*sm_cb_t)(space_map_entry_t *sme, void *arg); 210 211 int space_map_load(space_map_t *sm, zfs_range_tree_t *rt, maptype_t maptype); 212 int space_map_load_length(space_map_t *sm, zfs_range_tree_t *rt, 213 maptype_t maptype, uint64_t length); 214 int space_map_iterate(space_map_t *sm, uint64_t length, 215 sm_cb_t callback, void *arg); 216 int space_map_incremental_destroy(space_map_t *sm, sm_cb_t callback, void *arg, 217 dmu_tx_t *tx); 218 219 boolean_t space_map_histogram_verify(space_map_t *sm, zfs_range_tree_t *rt); 220 void space_map_histogram_clear(space_map_t *sm); 221 void space_map_histogram_add(space_map_t *sm, zfs_range_tree_t *rt, 222 dmu_tx_t *tx); 223 224 uint64_t space_map_object(space_map_t *sm); 225 int64_t space_map_allocated(space_map_t *sm); 226 uint64_t space_map_length(space_map_t *sm); 227 uint64_t space_map_entries(space_map_t *sm, zfs_range_tree_t *rt); 228 uint64_t space_map_nblocks(space_map_t *sm); 229 230 void space_map_write(space_map_t *sm, zfs_range_tree_t *rt, maptype_t maptype, 231 uint64_t vdev_id, dmu_tx_t *tx); 232 uint64_t space_map_estimate_optimal_size(space_map_t *sm, zfs_range_tree_t *rt, 233 uint64_t vdev_id); 234 void space_map_truncate(space_map_t *sm, int blocksize, dmu_tx_t *tx); 235 uint64_t space_map_alloc(objset_t *os, int blocksize, dmu_tx_t *tx); 236 void space_map_free(space_map_t *sm, dmu_tx_t *tx); 237 void space_map_free_obj(objset_t *os, uint64_t smobj, dmu_tx_t *tx); 238 239 int space_map_open(space_map_t **smp, objset_t *os, uint64_t object, 240 uint64_t start, uint64_t size, uint8_t shift); 241 void space_map_close(space_map_t *sm); 242 243 #ifdef __cplusplus 244 } 245 #endif 246 247 #endif /* _SYS_SPACE_MAP_H */ 248