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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.
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.
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]
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
27 * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
30 #ifndef _SYS_SPACE_MAP_H
31 #define _SYS_SPACE_MAP_H
34 #include <sys/range_tree.h>
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.
46 #define SPACE_MAP_SIZE_V0 (3 * sizeof (uint64_t))
47 #define SPACE_MAP_HISTOGRAM_SIZE 32
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.
54 * Note the smp_object is no longer used but remains in the structure
55 * for backward compatibility.
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 */
64 * The smp_histogram maintains a histogram of free regions. Each
65 * bucket, smp_histogram[i], contains the number of free regions
67 * 2^(i+sm_shift) <= size of free region in bytes < 2^(i+sm_shift+1)
69 uint64_t smp_histogram
[SPACE_MAP_HISTOGRAM_SIZE
];
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.
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 */
95 * ,---+--------+------------+---------------------------------.
96 * | 1 | action | syncpass | txg (lower bits) |
97 * `---+--------+------------+---------------------------------'
104 * ,-----------------------------------------------------------.
105 * | 0 | offset (sm_shift units) | type | run |
106 * `-----------------------------------------------------------'
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)
120 #define SM_DEBUG_ACTION_DECODE(x) BF64_DECODE(x, 60, 3)
121 #define SM_DEBUG_ACTION_ENCODE(x) BF64_ENCODE(x, 60, 3)
123 #define SM_DEBUG_SYNCPASS_DECODE(x) BF64_DECODE(x, 50, 10)
124 #define SM_DEBUG_SYNCPASS_ENCODE(x) BF64_ENCODE(x, 50, 10)
126 #define SM_DEBUG_TXG_DECODE(x) BF64_DECODE(x, 0, 50)
127 #define SM_DEBUG_TXG_ENCODE(x) BF64_ENCODE(x, 0, 50)
129 #define SM_RUN_MAX SM_RUN_DECODE(~0ULL)
136 int space_map_load(space_map_t
*sm
, range_tree_t
*rt
, maptype_t maptype
);
138 void space_map_histogram_clear(space_map_t
*sm
);
139 void space_map_histogram_add(space_map_t
*sm
, range_tree_t
*rt
,
142 void space_map_update(space_map_t
*sm
);
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
);
148 void space_map_write(space_map_t
*sm
, range_tree_t
*rt
, maptype_t maptype
,
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
);
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
);
158 int64_t space_map_alloc_delta(space_map_t
*sm
);
164 #endif /* _SYS_SPACE_MAP_H */