blob: eb54d906b34e13244ddf073ad36edcd537dfc8b8 [file] [log] [blame]
Jorgen Lundman4d3c95f2012-07-19 20:48:25 +00001/*
2 * GRUB -- GRand Unified Bootloader
3 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
4 *
Wolfgang Denk1a459662013-07-08 09:37:19 +02005 * SPDX-License-Identifier: GPL-2.0+
Jorgen Lundman4d3c95f2012-07-19 20:48:25 +00006 */
7/*
8 * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
9 */
10
11#ifndef ZFS_SPA_HEADER
12#define ZFS_SPA_HEADER 1
13
14
15/*
16 * General-purpose 32-bit and 64-bit bitfield encodings.
17 */
18#define BF32_DECODE(x, low, len) P2PHASE((x) >> (low), 1U << (len))
19#define BF64_DECODE(x, low, len) P2PHASE((x) >> (low), 1ULL << (len))
20#define BF32_ENCODE(x, low, len) (P2PHASE((x), 1U << (len)) << (low))
21#define BF64_ENCODE(x, low, len) (P2PHASE((x), 1ULL << (len)) << (low))
22
23#define BF32_GET(x, low, len) BF32_DECODE(x, low, len)
24#define BF64_GET(x, low, len) BF64_DECODE(x, low, len)
25
26#define BF32_SET(x, low, len, val) \
27 ((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
28#define BF64_SET(x, low, len, val) \
29 ((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))
30
31#define BF32_GET_SB(x, low, len, shift, bias) \
32 ((BF32_GET(x, low, len) + (bias)) << (shift))
33#define BF64_GET_SB(x, low, len, shift, bias) \
34 ((BF64_GET(x, low, len) + (bias)) << (shift))
35
36#define BF32_SET_SB(x, low, len, shift, bias, val) \
37 BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
38#define BF64_SET_SB(x, low, len, shift, bias, val) \
39 BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
40
41/*
42 * We currently support nine block sizes, from 512 bytes to 128K.
43 * We could go higher, but the benefits are near-zero and the cost
44 * of COWing a giant block to modify one byte would become excessive.
45 */
46#define SPA_MINBLOCKSHIFT 9
47#define SPA_MAXBLOCKSHIFT 17
48#define SPA_MINBLOCKSIZE (1ULL << SPA_MINBLOCKSHIFT)
49#define SPA_MAXBLOCKSIZE (1ULL << SPA_MAXBLOCKSHIFT)
50
51#define SPA_BLOCKSIZES (SPA_MAXBLOCKSHIFT - SPA_MINBLOCKSHIFT + 1)
52
53/*
54 * Size of block to hold the configuration data (a packed nvlist)
55 */
56#define SPA_CONFIG_BLOCKSIZE (1 << 14)
57
58/*
59 * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
60 * The ASIZE encoding should be at least 64 times larger (6 more bits)
61 * to support up to 4-way RAID-Z mirror mode with worst-case gang block
62 * overhead, three DVAs per bp, plus one more bit in case we do anything
63 * else that expands the ASIZE.
64 */
65#define SPA_LSIZEBITS 16 /* LSIZE up to 32M (2^16 * 512) */
66#define SPA_PSIZEBITS 16 /* PSIZE up to 32M (2^16 * 512) */
67#define SPA_ASIZEBITS 24 /* ASIZE up to 64 times larger */
68
69/*
70 * All SPA data is represented by 128-bit data virtual addresses (DVAs).
71 * The members of the dva_t should be considered opaque outside the SPA.
72 */
73typedef struct dva {
74 uint64_t dva_word[2];
75} dva_t;
76
77/*
78 * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
79 */
80typedef struct zio_cksum {
81 uint64_t zc_word[4];
82} zio_cksum_t;
83
84/*
85 * Each block is described by its DVAs, time of birth, checksum, etc.
86 * The word-by-word, bit-by-bit layout of the blkptr is as follows:
87 *
88 * 64 56 48 40 32 24 16 8 0
89 * +-------+-------+-------+-------+-------+-------+-------+-------+
90 * 0 | vdev1 | GRID | ASIZE |
91 * +-------+-------+-------+-------+-------+-------+-------+-------+
92 * 1 |G| offset1 |
93 * +-------+-------+-------+-------+-------+-------+-------+-------+
94 * 2 | vdev2 | GRID | ASIZE |
95 * +-------+-------+-------+-------+-------+-------+-------+-------+
96 * 3 |G| offset2 |
97 * +-------+-------+-------+-------+-------+-------+-------+-------+
98 * 4 | vdev3 | GRID | ASIZE |
99 * +-------+-------+-------+-------+-------+-------+-------+-------+
100 * 5 |G| offset3 |
101 * +-------+-------+-------+-------+-------+-------+-------+-------+
102 * 6 |BDX|lvl| type | cksum | comp | PSIZE | LSIZE |
103 * +-------+-------+-------+-------+-------+-------+-------+-------+
104 * 7 | padding |
105 * +-------+-------+-------+-------+-------+-------+-------+-------+
106 * 8 | padding |
107 * +-------+-------+-------+-------+-------+-------+-------+-------+
108 * 9 | physical birth txg |
109 * +-------+-------+-------+-------+-------+-------+-------+-------+
110 * a | logical birth txg |
111 * +-------+-------+-------+-------+-------+-------+-------+-------+
112 * b | fill count |
113 * +-------+-------+-------+-------+-------+-------+-------+-------+
114 * c | checksum[0] |
115 * +-------+-------+-------+-------+-------+-------+-------+-------+
116 * d | checksum[1] |
117 * +-------+-------+-------+-------+-------+-------+-------+-------+
118 * e | checksum[2] |
119 * +-------+-------+-------+-------+-------+-------+-------+-------+
120 * f | checksum[3] |
121 * +-------+-------+-------+-------+-------+-------+-------+-------+
122 *
123 * Legend:
124 *
125 * vdev virtual device ID
126 * offset offset into virtual device
127 * LSIZE logical size
128 * PSIZE physical size (after compression)
129 * ASIZE allocated size (including RAID-Z parity and gang block headers)
130 * GRID RAID-Z layout information (reserved for future use)
131 * cksum checksum function
132 * comp compression function
133 * G gang block indicator
134 * B byteorder (endianness)
135 * D dedup
136 * X unused
137 * lvl level of indirection
138 * type DMU object type
139 * phys birth txg of block allocation; zero if same as logical birth txg
140 * log. birth transaction group in which the block was logically born
141 * fill count number of non-zero blocks under this bp
142 * checksum[4] 256-bit checksum of the data this bp describes
143 */
144#define SPA_BLKPTRSHIFT 7 /* blkptr_t is 128 bytes */
145#define SPA_DVAS_PER_BP 3 /* Number of DVAs in a bp */
146
147typedef struct blkptr {
148 dva_t blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
149 uint64_t blk_prop; /* size, compression, type, etc */
150 uint64_t blk_pad[2]; /* Extra space for the future */
151 uint64_t blk_phys_birth; /* txg when block was allocated */
152 uint64_t blk_birth; /* transaction group at birth */
153 uint64_t blk_fill; /* fill count */
154 zio_cksum_t blk_cksum; /* 256-bit checksum */
155} blkptr_t;
156
157/*
158 * Macros to get and set fields in a bp or DVA.
159 */
160#define DVA_GET_ASIZE(dva) \
161 BF64_GET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0)
162#define DVA_SET_ASIZE(dva, x) \
163 BF64_SET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0, x)
164
165#define DVA_GET_GRID(dva) BF64_GET((dva)->dva_word[0], 24, 8)
166#define DVA_SET_GRID(dva, x) BF64_SET((dva)->dva_word[0], 24, 8, x)
167
168#define DVA_GET_VDEV(dva) BF64_GET((dva)->dva_word[0], 32, 32)
169#define DVA_SET_VDEV(dva, x) BF64_SET((dva)->dva_word[0], 32, 32, x)
170
171#define DVA_GET_GANG(dva) BF64_GET((dva)->dva_word[1], 63, 1)
172#define DVA_SET_GANG(dva, x) BF64_SET((dva)->dva_word[1], 63, 1, x)
173
174#define BP_GET_LSIZE(bp) \
175 BF64_GET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1)
176#define BP_SET_LSIZE(bp, x) \
177 BF64_SET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1, x)
178
179#define BP_GET_COMPRESS(bp) BF64_GET((bp)->blk_prop, 32, 8)
180#define BP_SET_COMPRESS(bp, x) BF64_SET((bp)->blk_prop, 32, 8, x)
181
182#define BP_GET_CHECKSUM(bp) BF64_GET((bp)->blk_prop, 40, 8)
183#define BP_SET_CHECKSUM(bp, x) BF64_SET((bp)->blk_prop, 40, 8, x)
184
185#define BP_GET_TYPE(bp) BF64_GET((bp)->blk_prop, 48, 8)
186#define BP_SET_TYPE(bp, x) BF64_SET((bp)->blk_prop, 48, 8, x)
187
188#define BP_GET_LEVEL(bp) BF64_GET((bp)->blk_prop, 56, 5)
189#define BP_SET_LEVEL(bp, x) BF64_SET((bp)->blk_prop, 56, 5, x)
190
191#define BP_GET_PROP_BIT_61(bp) BF64_GET((bp)->blk_prop, 61, 1)
192#define BP_SET_PROP_BIT_61(bp, x) BF64_SET((bp)->blk_prop, 61, 1, x)
193
194#define BP_GET_DEDUP(bp) BF64_GET((bp)->blk_prop, 62, 1)
195#define BP_SET_DEDUP(bp, x) BF64_SET((bp)->blk_prop, 62, 1, x)
196
197#define BP_GET_BYTEORDER(bp) (0 - BF64_GET((bp)->blk_prop, 63, 1))
198#define BP_SET_BYTEORDER(bp, x) BF64_SET((bp)->blk_prop, 63, 1, x)
199
200#define BP_PHYSICAL_BIRTH(bp) \
201 ((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
202
203#define BP_SET_BIRTH(bp, logical, physical) \
204 { \
205 (bp)->blk_birth = (logical); \
206 (bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \
207 }
208
209#define BP_GET_ASIZE(bp) \
210 (DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
211 DVA_GET_ASIZE(&(bp)->blk_dva[2]))
212
213#define BP_GET_UCSIZE(bp) \
214 ((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
215 BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));
216
217#define BP_GET_NDVAS(bp) \
218 (!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
219 !!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
220 !!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
221
222#define BP_COUNT_GANG(bp) \
223 (DVA_GET_GANG(&(bp)->blk_dva[0]) + \
224 DVA_GET_GANG(&(bp)->blk_dva[1]) + \
225 DVA_GET_GANG(&(bp)->blk_dva[2]))
226
227#define DVA_EQUAL(dva1, dva2) \
228 ((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
229 (dva1)->dva_word[0] == (dva2)->dva_word[0])
230
231#define BP_EQUAL(bp1, bp2) \
232 (BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) && \
233 DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) && \
234 DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) && \
235 DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2]))
236
237#define ZIO_CHECKSUM_EQUAL(zc1, zc2) \
238 (0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
239 ((zc1).zc_word[1] - (zc2).zc_word[1]) | \
240 ((zc1).zc_word[2] - (zc2).zc_word[2]) | \
241 ((zc1).zc_word[3] - (zc2).zc_word[3])))
242
243#define DVA_IS_VALID(dva) (DVA_GET_ASIZE(dva) != 0)
244
245#define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3) \
246 { \
247 (zcp)->zc_word[0] = w0; \
248 (zcp)->zc_word[1] = w1; \
249 (zcp)->zc_word[2] = w2; \
250 (zcp)->zc_word[3] = w3; \
251 }
252
253#define BP_IDENTITY(bp) (&(bp)->blk_dva[0])
254#define BP_IS_GANG(bp) DVA_GET_GANG(BP_IDENTITY(bp))
255#define BP_IS_HOLE(bp) ((bp)->blk_birth == 0)
256
257/* BP_IS_RAIDZ(bp) assumes no block compression */
258#define BP_IS_RAIDZ(bp) (DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \
259 BP_GET_PSIZE(bp))
260
261#define BP_ZERO(bp) \
262 { \
263 (bp)->blk_dva[0].dva_word[0] = 0; \
264 (bp)->blk_dva[0].dva_word[1] = 0; \
265 (bp)->blk_dva[1].dva_word[0] = 0; \
266 (bp)->blk_dva[1].dva_word[1] = 0; \
267 (bp)->blk_dva[2].dva_word[0] = 0; \
268 (bp)->blk_dva[2].dva_word[1] = 0; \
269 (bp)->blk_prop = 0; \
270 (bp)->blk_pad[0] = 0; \
271 (bp)->blk_pad[1] = 0; \
272 (bp)->blk_phys_birth = 0; \
273 (bp)->blk_birth = 0; \
274 (bp)->blk_fill = 0; \
275 ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \
276 }
277
278#define BP_SPRINTF_LEN 320
279
280#endif /* ! ZFS_SPA_HEADER */