blob: cd2ddf58e77240bbdd82e600d7a215dcd518e819 [file] [log] [blame]
Tom Rini83d290c2018-05-06 17:58:06 -04001/* SPDX-License-Identifier: GPL-2.0+ */
Jorgen Lundman4d3c95f2012-07-19 20:48:25 +00002/*
3 * GRUB -- GRand Unified Bootloader
4 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
Jorgen Lundman4d3c95f2012-07-19 20:48:25 +00005 */
6/*
7 * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
8 */
9
10#ifndef ZFS_SPA_HEADER
11#define ZFS_SPA_HEADER 1
12
13
14/*
15 * General-purpose 32-bit and 64-bit bitfield encodings.
16 */
17#define BF32_DECODE(x, low, len) P2PHASE((x) >> (low), 1U << (len))
18#define BF64_DECODE(x, low, len) P2PHASE((x) >> (low), 1ULL << (len))
19#define BF32_ENCODE(x, low, len) (P2PHASE((x), 1U << (len)) << (low))
20#define BF64_ENCODE(x, low, len) (P2PHASE((x), 1ULL << (len)) << (low))
21
22#define BF32_GET(x, low, len) BF32_DECODE(x, low, len)
23#define BF64_GET(x, low, len) BF64_DECODE(x, low, len)
24
25#define BF32_SET(x, low, len, val) \
26 ((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
27#define BF64_SET(x, low, len, val) \
28 ((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))
29
30#define BF32_GET_SB(x, low, len, shift, bias) \
31 ((BF32_GET(x, low, len) + (bias)) << (shift))
32#define BF64_GET_SB(x, low, len, shift, bias) \
33 ((BF64_GET(x, low, len) + (bias)) << (shift))
34
35#define BF32_SET_SB(x, low, len, shift, bias, val) \
36 BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
37#define BF64_SET_SB(x, low, len, shift, bias, val) \
38 BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
39
40/*
41 * We currently support nine block sizes, from 512 bytes to 128K.
42 * We could go higher, but the benefits are near-zero and the cost
43 * of COWing a giant block to modify one byte would become excessive.
44 */
45#define SPA_MINBLOCKSHIFT 9
46#define SPA_MAXBLOCKSHIFT 17
47#define SPA_MINBLOCKSIZE (1ULL << SPA_MINBLOCKSHIFT)
48#define SPA_MAXBLOCKSIZE (1ULL << SPA_MAXBLOCKSHIFT)
49
50#define SPA_BLOCKSIZES (SPA_MAXBLOCKSHIFT - SPA_MINBLOCKSHIFT + 1)
51
52/*
53 * Size of block to hold the configuration data (a packed nvlist)
54 */
55#define SPA_CONFIG_BLOCKSIZE (1 << 14)
56
57/*
58 * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
59 * The ASIZE encoding should be at least 64 times larger (6 more bits)
60 * to support up to 4-way RAID-Z mirror mode with worst-case gang block
61 * overhead, three DVAs per bp, plus one more bit in case we do anything
62 * else that expands the ASIZE.
63 */
64#define SPA_LSIZEBITS 16 /* LSIZE up to 32M (2^16 * 512) */
65#define SPA_PSIZEBITS 16 /* PSIZE up to 32M (2^16 * 512) */
66#define SPA_ASIZEBITS 24 /* ASIZE up to 64 times larger */
67
68/*
69 * All SPA data is represented by 128-bit data virtual addresses (DVAs).
70 * The members of the dva_t should be considered opaque outside the SPA.
71 */
72typedef struct dva {
73 uint64_t dva_word[2];
74} dva_t;
75
76/*
77 * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
78 */
79typedef struct zio_cksum {
80 uint64_t zc_word[4];
81} zio_cksum_t;
82
83/*
84 * Each block is described by its DVAs, time of birth, checksum, etc.
85 * The word-by-word, bit-by-bit layout of the blkptr is as follows:
86 *
87 * 64 56 48 40 32 24 16 8 0
88 * +-------+-------+-------+-------+-------+-------+-------+-------+
89 * 0 | vdev1 | GRID | ASIZE |
90 * +-------+-------+-------+-------+-------+-------+-------+-------+
91 * 1 |G| offset1 |
92 * +-------+-------+-------+-------+-------+-------+-------+-------+
93 * 2 | vdev2 | GRID | ASIZE |
94 * +-------+-------+-------+-------+-------+-------+-------+-------+
95 * 3 |G| offset2 |
96 * +-------+-------+-------+-------+-------+-------+-------+-------+
97 * 4 | vdev3 | GRID | ASIZE |
98 * +-------+-------+-------+-------+-------+-------+-------+-------+
99 * 5 |G| offset3 |
100 * +-------+-------+-------+-------+-------+-------+-------+-------+
101 * 6 |BDX|lvl| type | cksum | comp | PSIZE | LSIZE |
102 * +-------+-------+-------+-------+-------+-------+-------+-------+
103 * 7 | padding |
104 * +-------+-------+-------+-------+-------+-------+-------+-------+
105 * 8 | padding |
106 * +-------+-------+-------+-------+-------+-------+-------+-------+
107 * 9 | physical birth txg |
108 * +-------+-------+-------+-------+-------+-------+-------+-------+
109 * a | logical birth txg |
110 * +-------+-------+-------+-------+-------+-------+-------+-------+
111 * b | fill count |
112 * +-------+-------+-------+-------+-------+-------+-------+-------+
113 * c | checksum[0] |
114 * +-------+-------+-------+-------+-------+-------+-------+-------+
115 * d | checksum[1] |
116 * +-------+-------+-------+-------+-------+-------+-------+-------+
117 * e | checksum[2] |
118 * +-------+-------+-------+-------+-------+-------+-------+-------+
119 * f | checksum[3] |
120 * +-------+-------+-------+-------+-------+-------+-------+-------+
121 *
122 * Legend:
123 *
124 * vdev virtual device ID
125 * offset offset into virtual device
126 * LSIZE logical size
127 * PSIZE physical size (after compression)
128 * ASIZE allocated size (including RAID-Z parity and gang block headers)
129 * GRID RAID-Z layout information (reserved for future use)
130 * cksum checksum function
131 * comp compression function
132 * G gang block indicator
133 * B byteorder (endianness)
134 * D dedup
135 * X unused
136 * lvl level of indirection
137 * type DMU object type
138 * phys birth txg of block allocation; zero if same as logical birth txg
139 * log. birth transaction group in which the block was logically born
140 * fill count number of non-zero blocks under this bp
141 * checksum[4] 256-bit checksum of the data this bp describes
142 */
143#define SPA_BLKPTRSHIFT 7 /* blkptr_t is 128 bytes */
144#define SPA_DVAS_PER_BP 3 /* Number of DVAs in a bp */
145
146typedef struct blkptr {
147 dva_t blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
148 uint64_t blk_prop; /* size, compression, type, etc */
149 uint64_t blk_pad[2]; /* Extra space for the future */
150 uint64_t blk_phys_birth; /* txg when block was allocated */
151 uint64_t blk_birth; /* transaction group at birth */
152 uint64_t blk_fill; /* fill count */
153 zio_cksum_t blk_cksum; /* 256-bit checksum */
154} blkptr_t;
155
156/*
157 * Macros to get and set fields in a bp or DVA.
158 */
159#define DVA_GET_ASIZE(dva) \
160 BF64_GET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0)
161#define DVA_SET_ASIZE(dva, x) \
162 BF64_SET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0, x)
163
164#define DVA_GET_GRID(dva) BF64_GET((dva)->dva_word[0], 24, 8)
165#define DVA_SET_GRID(dva, x) BF64_SET((dva)->dva_word[0], 24, 8, x)
166
167#define DVA_GET_VDEV(dva) BF64_GET((dva)->dva_word[0], 32, 32)
168#define DVA_SET_VDEV(dva, x) BF64_SET((dva)->dva_word[0], 32, 32, x)
169
170#define DVA_GET_GANG(dva) BF64_GET((dva)->dva_word[1], 63, 1)
171#define DVA_SET_GANG(dva, x) BF64_SET((dva)->dva_word[1], 63, 1, x)
172
173#define BP_GET_LSIZE(bp) \
174 BF64_GET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1)
175#define BP_SET_LSIZE(bp, x) \
176 BF64_SET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1, x)
177
178#define BP_GET_COMPRESS(bp) BF64_GET((bp)->blk_prop, 32, 8)
179#define BP_SET_COMPRESS(bp, x) BF64_SET((bp)->blk_prop, 32, 8, x)
180
181#define BP_GET_CHECKSUM(bp) BF64_GET((bp)->blk_prop, 40, 8)
182#define BP_SET_CHECKSUM(bp, x) BF64_SET((bp)->blk_prop, 40, 8, x)
183
184#define BP_GET_TYPE(bp) BF64_GET((bp)->blk_prop, 48, 8)
185#define BP_SET_TYPE(bp, x) BF64_SET((bp)->blk_prop, 48, 8, x)
186
187#define BP_GET_LEVEL(bp) BF64_GET((bp)->blk_prop, 56, 5)
188#define BP_SET_LEVEL(bp, x) BF64_SET((bp)->blk_prop, 56, 5, x)
189
190#define BP_GET_PROP_BIT_61(bp) BF64_GET((bp)->blk_prop, 61, 1)
191#define BP_SET_PROP_BIT_61(bp, x) BF64_SET((bp)->blk_prop, 61, 1, x)
192
193#define BP_GET_DEDUP(bp) BF64_GET((bp)->blk_prop, 62, 1)
194#define BP_SET_DEDUP(bp, x) BF64_SET((bp)->blk_prop, 62, 1, x)
195
196#define BP_GET_BYTEORDER(bp) (0 - BF64_GET((bp)->blk_prop, 63, 1))
197#define BP_SET_BYTEORDER(bp, x) BF64_SET((bp)->blk_prop, 63, 1, x)
198
199#define BP_PHYSICAL_BIRTH(bp) \
200 ((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
201
202#define BP_SET_BIRTH(bp, logical, physical) \
203 { \
204 (bp)->blk_birth = (logical); \
205 (bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \
206 }
207
208#define BP_GET_ASIZE(bp) \
209 (DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
210 DVA_GET_ASIZE(&(bp)->blk_dva[2]))
211
212#define BP_GET_UCSIZE(bp) \
213 ((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
214 BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));
215
216#define BP_GET_NDVAS(bp) \
217 (!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
218 !!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
219 !!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
220
221#define BP_COUNT_GANG(bp) \
222 (DVA_GET_GANG(&(bp)->blk_dva[0]) + \
223 DVA_GET_GANG(&(bp)->blk_dva[1]) + \
224 DVA_GET_GANG(&(bp)->blk_dva[2]))
225
226#define DVA_EQUAL(dva1, dva2) \
227 ((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
228 (dva1)->dva_word[0] == (dva2)->dva_word[0])
229
230#define BP_EQUAL(bp1, bp2) \
231 (BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) && \
232 DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) && \
233 DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) && \
234 DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2]))
235
236#define ZIO_CHECKSUM_EQUAL(zc1, zc2) \
237 (0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
238 ((zc1).zc_word[1] - (zc2).zc_word[1]) | \
239 ((zc1).zc_word[2] - (zc2).zc_word[2]) | \
240 ((zc1).zc_word[3] - (zc2).zc_word[3])))
241
242#define DVA_IS_VALID(dva) (DVA_GET_ASIZE(dva) != 0)
243
244#define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3) \
245 { \
246 (zcp)->zc_word[0] = w0; \
247 (zcp)->zc_word[1] = w1; \
248 (zcp)->zc_word[2] = w2; \
249 (zcp)->zc_word[3] = w3; \
250 }
251
252#define BP_IDENTITY(bp) (&(bp)->blk_dva[0])
253#define BP_IS_GANG(bp) DVA_GET_GANG(BP_IDENTITY(bp))
254#define BP_IS_HOLE(bp) ((bp)->blk_birth == 0)
255
256/* BP_IS_RAIDZ(bp) assumes no block compression */
257#define BP_IS_RAIDZ(bp) (DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \
258 BP_GET_PSIZE(bp))
259
260#define BP_ZERO(bp) \
261 { \
262 (bp)->blk_dva[0].dva_word[0] = 0; \
263 (bp)->blk_dva[0].dva_word[1] = 0; \
264 (bp)->blk_dva[1].dva_word[0] = 0; \
265 (bp)->blk_dva[1].dva_word[1] = 0; \
266 (bp)->blk_dva[2].dva_word[0] = 0; \
267 (bp)->blk_dva[2].dva_word[1] = 0; \
268 (bp)->blk_prop = 0; \
269 (bp)->blk_pad[0] = 0; \
270 (bp)->blk_pad[1] = 0; \
271 (bp)->blk_phys_birth = 0; \
272 (bp)->blk_birth = 0; \
273 (bp)->blk_fill = 0; \
274 ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \
275 }
276
277#define BP_SPRINTF_LEN 320
278
279#endif /* ! ZFS_SPA_HEADER */