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, 2014 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 uint64_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 typedef struct space_map { 78 uint64_t sm_start; /* start of map */ 79 uint64_t sm_size; /* size of map */ 80 uint8_t sm_shift; /* unit shift */ 81 uint64_t sm_length; /* synced length */ 82 uint64_t sm_alloc; /* synced space allocated */ 83 objset_t *sm_os; /* objset for this map */ 84 uint64_t sm_object; /* object id for this map */ 85 uint32_t sm_blksz; /* block size for space map */ 86 dmu_buf_t *sm_dbuf; /* space_map_phys_t dbuf */ 87 space_map_phys_t *sm_phys; /* on-disk space map */ 88 kmutex_t *sm_lock; /* pointer to lock that protects map */ 89 } space_map_t; 90 91 /* 92 * debug entry 93 * 94 * 1 3 10 50 95 * ,---+--------+------------+---------------------------------. 96 * | 1 | action | syncpass | txg (lower bits) | 97 * `---+--------+------------+---------------------------------' 98 * 63 62 60 59 50 49 0 99 * 100 * 101 * non-debug entry 102 * 103 * 1 47 1 15 104 * ,-----------------------------------------------------------. 105 * | 0 | offset (sm_shift units) | type | run | 106 * `-----------------------------------------------------------' 107 * 63 62 17 16 15 0 108 */ 109 110 /* All this stuff takes and returns bytes */ 111 #define SM_RUN_DECODE(x) (BF64_DECODE(x, 0, 15) + 1) 112 #define SM_RUN_ENCODE(x) BF64_ENCODE((x) - 1, 0, 15) 113 #define SM_TYPE_DECODE(x) BF64_DECODE(x, 15, 1) 114 #define SM_TYPE_ENCODE(x) BF64_ENCODE(x, 15, 1) 115 #define SM_OFFSET_DECODE(x) BF64_DECODE(x, 16, 47) 116 #define SM_OFFSET_ENCODE(x) BF64_ENCODE(x, 16, 47) 117 #define SM_DEBUG_DECODE(x) BF64_DECODE(x, 63, 1) 118 #define SM_DEBUG_ENCODE(x) BF64_ENCODE(x, 63, 1) 119 120 #define SM_DEBUG_ACTION_DECODE(x) BF64_DECODE(x, 60, 3) 121 #define SM_DEBUG_ACTION_ENCODE(x) BF64_ENCODE(x, 60, 3) 122 123 #define SM_DEBUG_SYNCPASS_DECODE(x) BF64_DECODE(x, 50, 10) 124 #define SM_DEBUG_SYNCPASS_ENCODE(x) BF64_ENCODE(x, 50, 10) 125 126 #define SM_DEBUG_TXG_DECODE(x) BF64_DECODE(x, 0, 50) 127 #define SM_DEBUG_TXG_ENCODE(x) BF64_ENCODE(x, 0, 50) 128 129 #define SM_RUN_MAX SM_RUN_DECODE(~0ULL) 130 131 typedef enum { 132 SM_ALLOC, 133 SM_FREE 134 } maptype_t; 135 136 int space_map_load(space_map_t *sm, range_tree_t *rt, maptype_t maptype); 137 138 void space_map_histogram_clear(space_map_t *sm); 139 void space_map_histogram_add(space_map_t *sm, range_tree_t *rt, 140 dmu_tx_t *tx); 141 142 void space_map_update(space_map_t *sm); 143 144 uint64_t space_map_object(space_map_t *sm); 145 uint64_t space_map_allocated(space_map_t *sm); 146 uint64_t space_map_length(space_map_t *sm); 147 148 void space_map_write(space_map_t *sm, range_tree_t *rt, maptype_t maptype, 149 dmu_tx_t *tx); 150 void space_map_truncate(space_map_t *sm, dmu_tx_t *tx); 151 uint64_t space_map_alloc(objset_t *os, dmu_tx_t *tx); 152 void space_map_free(space_map_t *sm, dmu_tx_t *tx); 153 154 int space_map_open(space_map_t **smp, objset_t *os, uint64_t object, 155 uint64_t start, uint64_t size, uint8_t shift, kmutex_t *lp); 156 void space_map_close(space_map_t *sm); 157 158 int64_t space_map_alloc_delta(space_map_t *sm); 159 160 #ifdef __cplusplus 161 } 162 #endif 163 164 #endif /* _SYS_SPACE_MAP_H */ 165