1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
|
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _SYS_SPA_H
#define _SYS_SPA_H
/*
* General-purpose 32-bit and 64-bit bitfield encodings.
*/
#define BF32_DECODE(x, low, len) P2PHASE((x) >> (low), 1U << (len))
#define BF64_DECODE(x, low, len) P2PHASE((x) >> (low), 1ULL << (len))
#define BF32_ENCODE(x, low, len) (P2PHASE((x), 1U << (len)) << (low))
#define BF64_ENCODE(x, low, len) (P2PHASE((x), 1ULL << (len)) << (low))
#define BF32_GET(x, low, len) BF32_DECODE(x, low, len)
#define BF64_GET(x, low, len) BF64_DECODE(x, low, len)
#define BF32_SET(x, low, len, val) \
((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
#define BF64_SET(x, low, len, val) \
((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))
#define BF32_GET_SB(x, low, len, shift, bias) \
((BF32_GET(x, low, len) + (bias)) << (shift))
#define BF64_GET_SB(x, low, len, shift, bias) \
((BF64_GET(x, low, len) + (bias)) << (shift))
#define BF32_SET_SB(x, low, len, shift, bias, val) \
BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
#define BF64_SET_SB(x, low, len, shift, bias, val) \
BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
/*
* We currently support nine block sizes, from 512 bytes to 128K.
* We could go higher, but the benefits are near-zero and the cost
* of COWing a giant block to modify one byte would become excessive.
*/
#define SPA_MINBLOCKSHIFT 9
#define SPA_MAXBLOCKSHIFT 17
#define SPA_MINBLOCKSIZE (1ULL << SPA_MINBLOCKSHIFT)
#define SPA_MAXBLOCKSIZE (1ULL << SPA_MAXBLOCKSHIFT)
#define SPA_BLOCKSIZES (SPA_MAXBLOCKSHIFT - SPA_MINBLOCKSHIFT + 1)
/*
* The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
* The ASIZE encoding should be at least 64 times larger (6 more bits)
* to support up to 4-way RAID-Z mirror mode with worst-case gang block
* overhead, three DVAs per bp, plus one more bit in case we do anything
* else that expands the ASIZE.
*/
#define SPA_LSIZEBITS 16 /* LSIZE up to 32M (2^16 * 512) */
#define SPA_PSIZEBITS 16 /* PSIZE up to 32M (2^16 * 512) */
#define SPA_ASIZEBITS 24 /* ASIZE up to 64 times larger */
/*
* All SPA data is represented by 128-bit data virtual addresses (DVAs).
* The members of the dva_t should be considered opaque outside the SPA.
*/
typedef struct dva {
uint64_t dva_word[2];
} dva_t;
/*
* Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
*/
typedef struct zio_cksum {
uint64_t zc_word[4];
} zio_cksum_t;
/*
* Each block is described by its DVAs, time of birth, checksum, etc.
* The word-by-word, bit-by-bit layout of the blkptr is as follows:
*
* 64 56 48 40 32 24 16 8 0
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 0 | vdev1 | GRID | ASIZE |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 1 |G| offset1 |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 2 | vdev2 | GRID | ASIZE |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 3 |G| offset2 |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 4 | vdev3 | GRID | ASIZE |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 5 |G| offset3 |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 6 |E| lvl | type | cksum | comp | PSIZE | LSIZE |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 7 | padding |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 8 | padding |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* 9 | padding |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* a | birth txg |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* b | fill count |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* c | checksum[0] |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* d | checksum[1] |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* e | checksum[2] |
* +-------+-------+-------+-------+-------+-------+-------+-------+
* f | checksum[3] |
* +-------+-------+-------+-------+-------+-------+-------+-------+
*
* Legend:
*
* vdev virtual device ID
* offset offset into virtual device
* LSIZE logical size
* PSIZE physical size (after compression)
* ASIZE allocated size (including RAID-Z parity and gang block headers)
* GRID RAID-Z layout information (reserved for future use)
* cksum checksum function
* comp compression function
* G gang block indicator
* E endianness
* type DMU object type
* lvl level of indirection
* birth txg transaction group in which the block was born
* fill count number of non-zero blocks under this bp
* checksum[4] 256-bit checksum of the data this bp describes
*/
typedef struct blkptr {
dva_t blk_dva[3]; /* 128-bit Data Virtual Address */
uint64_t blk_prop; /* size, compression, type, etc */
uint64_t blk_pad[3]; /* Extra space for the future */
uint64_t blk_birth; /* transaction group at birth */
uint64_t blk_fill; /* fill count */
zio_cksum_t blk_cksum; /* 256-bit checksum */
} blkptr_t;
#define SPA_BLKPTRSHIFT 7 /* blkptr_t is 128 bytes */
#define SPA_DVAS_PER_BP 3 /* Number of DVAs in a bp */
/*
* Macros to get and set fields in a bp or DVA.
*/
#define DVA_GET_ASIZE(dva) \
BF64_GET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0)
#define DVA_SET_ASIZE(dva, x) \
BF64_SET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0, x)
#define DVA_GET_GRID(dva) BF64_GET((dva)->dva_word[0], 24, 8)
#define DVA_SET_GRID(dva, x) BF64_SET((dva)->dva_word[0], 24, 8, x)
#define DVA_GET_VDEV(dva) BF64_GET((dva)->dva_word[0], 32, 32)
#define DVA_SET_VDEV(dva, x) BF64_SET((dva)->dva_word[0], 32, 32, x)
#define DVA_GET_OFFSET(dva) \
BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
#define DVA_SET_OFFSET(dva, x) \
BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
#define DVA_GET_GANG(dva) BF64_GET((dva)->dva_word[1], 63, 1)
#define DVA_SET_GANG(dva, x) BF64_SET((dva)->dva_word[1], 63, 1, x)
#define BP_GET_LSIZE(bp) \
(BP_IS_HOLE(bp) ? 0 : \
BF64_GET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1))
#define BP_SET_LSIZE(bp, x) \
BF64_SET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1, x)
#define BP_GET_PSIZE(bp) \
BF64_GET_SB((bp)->blk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1)
#define BP_SET_PSIZE(bp, x) \
BF64_SET_SB((bp)->blk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1, x)
#define BP_GET_COMPRESS(bp) BF64_GET((bp)->blk_prop, 32, 8)
#define BP_SET_COMPRESS(bp, x) BF64_SET((bp)->blk_prop, 32, 8, x)
#define BP_GET_CHECKSUM(bp) BF64_GET((bp)->blk_prop, 40, 8)
#define BP_SET_CHECKSUM(bp, x) BF64_SET((bp)->blk_prop, 40, 8, x)
#define BP_GET_TYPE(bp) BF64_GET((bp)->blk_prop, 48, 8)
#define BP_SET_TYPE(bp, x) BF64_SET((bp)->blk_prop, 48, 8, x)
#define BP_GET_LEVEL(bp) BF64_GET((bp)->blk_prop, 56, 5)
#define BP_SET_LEVEL(bp, x) BF64_SET((bp)->blk_prop, 56, 5, x)
#define BP_GET_BYTEORDER(bp) (0 - BF64_GET((bp)->blk_prop, 63, 1))
#define BP_SET_BYTEORDER(bp, x) BF64_SET((bp)->blk_prop, 63, 1, x)
#define BP_GET_ASIZE(bp) \
(DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
DVA_GET_ASIZE(&(bp)->blk_dva[2]))
#define BP_GET_UCSIZE(bp) \
((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));
#define BP_GET_NDVAS(bp) \
(!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
!!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
!!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
#define BP_COUNT_GANG(bp) \
(DVA_GET_GANG(&(bp)->blk_dva[0]) + \
DVA_GET_GANG(&(bp)->blk_dva[1]) + \
DVA_GET_GANG(&(bp)->blk_dva[2]))
#define DVA_EQUAL(dva1, dva2) \
((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
(dva1)->dva_word[0] == (dva2)->dva_word[0])
#define ZIO_CHECKSUM_EQUAL(zc1, zc2) \
(0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
((zc1).zc_word[1] - (zc2).zc_word[1]) | \
((zc1).zc_word[2] - (zc2).zc_word[2]) | \
((zc1).zc_word[3] - (zc2).zc_word[3])))
#define DVA_IS_VALID(dva) (DVA_GET_ASIZE(dva) != 0)
#define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3) \
{ \
(zcp)->zc_word[0] = w0; \
(zcp)->zc_word[1] = w1; \
(zcp)->zc_word[2] = w2; \
(zcp)->zc_word[3] = w3; \
}
#define BP_IDENTITY(bp) (&(bp)->blk_dva[0])
#define BP_IS_GANG(bp) DVA_GET_GANG(BP_IDENTITY(bp))
#define BP_IS_HOLE(bp) ((bp)->blk_birth == 0)
#define BP_IS_OLDER(bp, txg) (!BP_IS_HOLE(bp) && (bp)->blk_birth < (txg))
#define BP_ZERO(bp) \
{ \
(bp)->blk_dva[0].dva_word[0] = 0; \
(bp)->blk_dva[0].dva_word[1] = 0; \
(bp)->blk_dva[1].dva_word[0] = 0; \
(bp)->blk_dva[1].dva_word[1] = 0; \
(bp)->blk_dva[2].dva_word[0] = 0; \
(bp)->blk_dva[2].dva_word[1] = 0; \
(bp)->blk_prop = 0; \
(bp)->blk_pad[0] = 0; \
(bp)->blk_pad[1] = 0; \
(bp)->blk_pad[2] = 0; \
(bp)->blk_birth = 0; \
(bp)->blk_fill = 0; \
ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \
}
/*
* Note: the byteorder is either 0 or -1, both of which are palindromes.
* This simplifies the endianness handling a bit.
*/
#ifdef _BIG_ENDIAN
#define ZFS_HOST_BYTEORDER (0ULL)
#else
#define ZFS_HOST_BYTEORDER (-1ULL)
#endif
#define BP_SHOULD_BYTESWAP(bp) (BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)
#define BP_SPRINTF_LEN 320
#endif /* _SYS_SPA_H */
|
