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, 2017 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 uint64_t smp_object; /* on-disk space map object */ 59 uint64_t smp_objsize; /* size of the object */ 60 int64_t smp_alloc; /* space allocated from the map */ 61 uint64_t smp_pad[5]; /* reserved */ 62 63 /* 64 * The smp_histogram maintains a histogram of free regions. Each 65 * bucket, smp_histogram[i], contains the number of free regions 66 * whose size is: 67 * 2^(i+sm_shift) <= size of free region in bytes < 2^(i+sm_shift+1) 68 */ 69 uint64_t smp_histogram[SPACE_MAP_HISTOGRAM_SIZE]; 70 } space_map_phys_t; 71 72 /* 73 * The space map object defines a region of space, its size, how much is 74 * allocated, and the on-disk object that stores this information. 75 * Consumers of space maps may only access the members of this structure. 76 * 77 * Note: the space_map may not be accessed concurrently; consumers 78 * must provide external locking if required. 79 */ 80 typedef struct space_map { 81 uint64_t sm_start; /* start of map */ 82 uint64_t sm_size; /* size of map */ 83 uint8_t sm_shift; /* unit shift */ 84 uint64_t sm_length; /* synced length */ 85 int64_t sm_alloc; /* synced space allocated */ 86 objset_t *sm_os; /* objset for this map */ 87 uint64_t sm_object; /* object id for this map */ 88 uint32_t sm_blksz; /* block size for space map */ 89 dmu_buf_t *sm_dbuf; /* space_map_phys_t dbuf */ 90 space_map_phys_t *sm_phys; /* on-disk space map */ 91 } space_map_t; 92 93 /* 94 * debug entry 95 * 96 * 2 2 10 50 97 * +-----+-----+------------+----------------------------------+ 98 * | 1 0 | act | syncpass | txg (lower bits) | 99 * +-----+-----+------------+----------------------------------+ 100 * 63 62 61 60 59 50 49 0 101 * 102 * 103 * one-word entry 104 * 105 * 1 47 1 15 106 * +-----------------------------------------------------------+ 107 * | 0 | offset (sm_shift units) | type | run | 108 * +-----------------------------------------------------------+ 109 * 63 62 16 15 14 0 110 * 111 * 112 * two-word entry 113 * 114 * 2 2 36 24 115 * +-----+-----+---------------------------+-------------------+ 116 * | 1 1 | pad | run | vdev | 117 * +-----+-----+---------------------------+-------------------+ 118 * 63 62 61 60 59 24 23 0 119 * 120 * 1 63 121 * +------+----------------------------------------------------+ 122 * | type | offset | 123 * +------+----------------------------------------------------+ 124 * 63 62 0 125 * 126 * Note that a two-word entry will not strandle a block boundary. 127 * If necessary, the last word of a block will be padded with a 128 * debug entry (with act = syncpass = txg = 0). 129 */ 130 131 typedef enum { 132 SM_ALLOC, 133 SM_FREE 134 } maptype_t; 135 136 typedef struct space_map_entry { 137 maptype_t sme_type; 138 uint32_t sme_vdev; /* max is 2^24-1; SM_NO_VDEVID if not present */ 139 uint64_t sme_offset; /* max is 2^63-1; units of sm_shift */ 140 uint64_t sme_run; /* max is 2^36; units of sm_shift */ 141 } space_map_entry_t; 142 143 #define SM_NO_VDEVID (1 << SPA_VDEVBITS) 144 145 /* one-word entry constants */ 146 #define SM_DEBUG_PREFIX 2 147 #define SM_OFFSET_BITS 47 148 #define SM_RUN_BITS 15 149 150 /* two-word entry constants */ 151 #define SM2_PREFIX 3 152 #define SM2_OFFSET_BITS 63 153 #define SM2_RUN_BITS 36 154 155 #define SM_PREFIX_DECODE(x) BF64_DECODE(x, 62, 2) 156 #define SM_PREFIX_ENCODE(x) BF64_ENCODE(x, 62, 2) 157 158 #define SM_DEBUG_ACTION_DECODE(x) BF64_DECODE(x, 60, 2) 159 #define SM_DEBUG_ACTION_ENCODE(x) BF64_ENCODE(x, 60, 2) 160 #define SM_DEBUG_SYNCPASS_DECODE(x) BF64_DECODE(x, 50, 10) 161 #define SM_DEBUG_SYNCPASS_ENCODE(x) BF64_ENCODE(x, 50, 10) 162 #define SM_DEBUG_TXG_DECODE(x) BF64_DECODE(x, 0, 50) 163 #define SM_DEBUG_TXG_ENCODE(x) BF64_ENCODE(x, 0, 50) 164 165 #define SM_OFFSET_DECODE(x) BF64_DECODE(x, 16, SM_OFFSET_BITS) 166 #define SM_OFFSET_ENCODE(x) BF64_ENCODE(x, 16, SM_OFFSET_BITS) 167 #define SM_TYPE_DECODE(x) BF64_DECODE(x, 15, 1) 168 #define SM_TYPE_ENCODE(x) BF64_ENCODE(x, 15, 1) 169 #define SM_RUN_DECODE(x) (BF64_DECODE(x, 0, SM_RUN_BITS) + 1) 170 #define SM_RUN_ENCODE(x) BF64_ENCODE((x) - 1, 0, SM_RUN_BITS) 171 #define SM_RUN_MAX SM_RUN_DECODE(~0ULL) 172 #define SM_OFFSET_MAX SM_OFFSET_DECODE(~0ULL) 173 174 #define SM2_RUN_DECODE(x) (BF64_DECODE(x, SPA_VDEVBITS, SM2_RUN_BITS) + 1) 175 #define SM2_RUN_ENCODE(x) BF64_ENCODE((x) - 1, SPA_VDEVBITS, SM2_RUN_BITS) 176 #define SM2_VDEV_DECODE(x) BF64_DECODE(x, 0, SPA_VDEVBITS) 177 #define SM2_VDEV_ENCODE(x) BF64_ENCODE(x, 0, SPA_VDEVBITS) 178 #define SM2_TYPE_DECODE(x) BF64_DECODE(x, SM2_OFFSET_BITS, 1) 179 #define SM2_TYPE_ENCODE(x) BF64_ENCODE(x, SM2_OFFSET_BITS, 1) 180 #define SM2_OFFSET_DECODE(x) BF64_DECODE(x, 0, SM2_OFFSET_BITS) 181 #define SM2_OFFSET_ENCODE(x) BF64_ENCODE(x, 0, SM2_OFFSET_BITS) 182 #define SM2_RUN_MAX SM2_RUN_DECODE(~0ULL) 183 #define SM2_OFFSET_MAX SM2_OFFSET_DECODE(~0ULL) 184 185 boolean_t sm_entry_is_debug(uint64_t e); 186 boolean_t sm_entry_is_single_word(uint64_t e); 187 boolean_t sm_entry_is_double_word(uint64_t e); 188 189 typedef int (*sm_cb_t)(space_map_entry_t *sme, void *arg); 190 191 int space_map_load(space_map_t *sm, range_tree_t *rt, maptype_t maptype); 192 int space_map_iterate(space_map_t *sm, sm_cb_t callback, void *arg); 193 int space_map_incremental_destroy(space_map_t *sm, sm_cb_t callback, void *arg, 194 dmu_tx_t *tx); 195 196 void space_map_histogram_clear(space_map_t *sm); 197 void space_map_histogram_add(space_map_t *sm, range_tree_t *rt, 198 dmu_tx_t *tx); 199 200 void space_map_update(space_map_t *sm); 201 202 uint64_t space_map_object(space_map_t *sm); 203 uint64_t space_map_allocated(space_map_t *sm); 204 uint64_t space_map_length(space_map_t *sm); 205 206 void space_map_write(space_map_t *sm, range_tree_t *rt, maptype_t maptype, 207 uint64_t vdev_id, dmu_tx_t *tx); 208 uint64_t space_map_estimate_optimal_size(space_map_t *sm, range_tree_t *rt, 209 uint64_t vdev_id); 210 void space_map_truncate(space_map_t *sm, int blocksize, dmu_tx_t *tx); 211 uint64_t space_map_alloc(objset_t *os, int blocksize, dmu_tx_t *tx); 212 void space_map_free(space_map_t *sm, dmu_tx_t *tx); 213 void space_map_free_obj(objset_t *os, uint64_t smobj, dmu_tx_t *tx); 214 215 int space_map_open(space_map_t **smp, objset_t *os, uint64_t object, 216 uint64_t start, uint64_t size, uint8_t shift); 217 void space_map_close(space_map_t *sm); 218 219 int64_t space_map_alloc_delta(space_map_t *sm); 220 221 #ifdef __cplusplus 222 } 223 #endif 224 225 #endif /* _SYS_SPACE_MAP_H */ 226