xref: /illumos-gate/usr/src/grub/grub-0.97/stage2/zfs-include/spa.h (revision b515258426fed6c7311fd3f1dea697cfbd4085c6)
1 /*
2  *  GRUB  --  GRand Unified Bootloader
3  *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License as published by
7  *  the Free Software Foundation; either version 2 of the License, or
8  *  (at your option) any later version.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, write to the Free Software
17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19 
20 /*
21  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
22  * Use is subject to license terms.
23  */
24 
25 /*
26  * Copyright (c) 2013 by Delphix. All rights reserved.
27  */
28 
29 #ifndef _SYS_SPA_H
30 #define	_SYS_SPA_H
31 
32 /*
33  * General-purpose 32-bit and 64-bit bitfield encodings.
34  */
35 #define	BF32_DECODE(x, low, len)	P2PHASE((x) >> (low), 1U << (len))
36 #define	BF64_DECODE(x, low, len)	P2PHASE((x) >> (low), 1ULL << (len))
37 #define	BF32_ENCODE(x, low, len)	(P2PHASE((x), 1U << (len)) << (low))
38 #define	BF64_ENCODE(x, low, len)	(P2PHASE((x), 1ULL << (len)) << (low))
39 
40 #define	BF32_GET(x, low, len)		BF32_DECODE(x, low, len)
41 #define	BF64_GET(x, low, len)		BF64_DECODE(x, low, len)
42 
43 #define	BF32_SET(x, low, len, val)	\
44 	((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
45 #define	BF64_SET(x, low, len, val)	\
46 	((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))
47 
48 #define	BF32_GET_SB(x, low, len, shift, bias)	\
49 	((BF32_GET(x, low, len) + (bias)) << (shift))
50 #define	BF64_GET_SB(x, low, len, shift, bias)	\
51 	((BF64_GET(x, low, len) + (bias)) << (shift))
52 
53 #define	BF32_SET_SB(x, low, len, shift, bias, val)	\
54 	BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
55 #define	BF64_SET_SB(x, low, len, shift, bias, val)	\
56 	BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
57 
58 /*
59  * Note: GRUB can't actually read blocks larger than 128KB, due to lack
60  * of memory.  Therefore its SPA_MAXBLOCKSIZE is still 128KB.
61  */
62 #define	SPA_MINBLOCKSHIFT	9
63 #define	SPA_MAXBLOCKSHIFT	17
64 #define	SPA_MINBLOCKSIZE	(1ULL << SPA_MINBLOCKSHIFT)
65 #define	SPA_MAXBLOCKSIZE	(1ULL << SPA_MAXBLOCKSHIFT)
66 
67 /*
68  * Size of block to hold the configuration data (a packed nvlist)
69  */
70 #define	SPA_CONFIG_BLOCKSIZE	(1ULL << 14)
71 
72 /*
73  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
74  * The ASIZE encoding should be at least 64 times larger (6 more bits)
75  * to support up to 4-way RAID-Z mirror mode with worst-case gang block
76  * overhead, three DVAs per bp, plus one more bit in case we do anything
77  * else that expands the ASIZE.
78  */
79 #define	SPA_LSIZEBITS		16	/* LSIZE up to 32M (2^16 * 512)	*/
80 #define	SPA_PSIZEBITS		16	/* PSIZE up to 32M (2^16 * 512)	*/
81 #define	SPA_ASIZEBITS		24	/* ASIZE up to 64 times larger	*/
82 
83 /*
84  * All SPA data is represented by 128-bit data virtual addresses (DVAs).
85  * The members of the dva_t should be considered opaque outside the SPA.
86  */
87 typedef struct dva {
88 	uint64_t	dva_word[2];
89 } dva_t;
90 
91 /*
92  * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
93  */
94 typedef struct zio_cksum {
95 	uint64_t	zc_word[4];
96 } zio_cksum_t;
97 
98 /*
99  * Each block is described by its DVAs, time of birth, checksum, etc.
100  * The word-by-word, bit-by-bit layout of the blkptr is as follows:
101  *
102  *	64	56	48	40	32	24	16	8	0
103  *	+-------+-------+-------+-------+-------+-------+-------+-------+
104  * 0	|		vdev1		| GRID  |	  ASIZE		|
105  *	+-------+-------+-------+-------+-------+-------+-------+-------+
106  * 1	|G|			 offset1				|
107  *	+-------+-------+-------+-------+-------+-------+-------+-------+
108  * 2	|		vdev2		| GRID  |	  ASIZE		|
109  *	+-------+-------+-------+-------+-------+-------+-------+-------+
110  * 3	|G|			 offset2				|
111  *	+-------+-------+-------+-------+-------+-------+-------+-------+
112  * 4	|		vdev3		| GRID  |	  ASIZE		|
113  *	+-------+-------+-------+-------+-------+-------+-------+-------+
114  * 5	|G|			 offset3				|
115  *	+-------+-------+-------+-------+-------+-------+-------+-------+
116  * 6	|BDX|lvl| type	| cksum |E| comp|    PSIZE	|     LSIZE	|
117  *	+-------+-------+-------+-------+-------+-------+-------+-------+
118  * 7	|			padding					|
119  *	+-------+-------+-------+-------+-------+-------+-------+-------+
120  * 8	|			padding					|
121  *	+-------+-------+-------+-------+-------+-------+-------+-------+
122  * 9	|			physical birth txg			|
123  *	+-------+-------+-------+-------+-------+-------+-------+-------+
124  * a	|			logical birth txg			|
125  *	+-------+-------+-------+-------+-------+-------+-------+-------+
126  * b	|			fill count				|
127  *	+-------+-------+-------+-------+-------+-------+-------+-------+
128  * c	|			checksum[0]				|
129  *	+-------+-------+-------+-------+-------+-------+-------+-------+
130  * d	|			checksum[1]				|
131  *	+-------+-------+-------+-------+-------+-------+-------+-------+
132  * e	|			checksum[2]				|
133  *	+-------+-------+-------+-------+-------+-------+-------+-------+
134  * f	|			checksum[3]				|
135  *	+-------+-------+-------+-------+-------+-------+-------+-------+
136  *
137  * Legend:
138  *
139  * vdev		virtual device ID
140  * offset	offset into virtual device
141  * LSIZE	logical size
142  * PSIZE	physical size (after compression)
143  * ASIZE	allocated size (including RAID-Z parity and gang block headers)
144  * GRID		RAID-Z layout information (reserved for future use)
145  * cksum	checksum function
146  * comp		compression function
147  * G		gang block indicator
148  * B		byteorder (endianness)
149  * D		dedup
150  * X		encryption (on version 30, which is not supported)
151  * E		blkptr_t contains embedded data
152  * lvl		level of indirection
153  * type		DMU object type
154  * phys birth	txg of block allocation; zero if same as logical birth txg
155  * log. birth	transaction group in which the block was logically born
156  * fill count	number of non-zero blocks under this bp
157  * checksum[4]	256-bit checksum of the data this bp describes
158  */
159 #define	SPA_BLKPTRSHIFT	7		/* blkptr_t is 128 bytes	*/
160 #define	SPA_DVAS_PER_BP	3		/* Number of DVAs in a bp	*/
161 
162 typedef struct blkptr {
163 	dva_t		blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
164 	uint64_t	blk_prop;	/* size, compression, type, etc	    */
165 	uint64_t	blk_pad[2];	/* Extra space for the future	    */
166 	uint64_t	blk_phys_birth;	/* txg when block was allocated	    */
167 	uint64_t	blk_birth;	/* transaction group at birth	    */
168 	uint64_t	blk_fill;	/* fill count			    */
169 	zio_cksum_t	blk_cksum;	/* 256-bit checksum		    */
170 } blkptr_t;
171 
172 /*
173  * Macros to get and set fields in a bp or DVA.
174  */
175 #define	DVA_GET_ASIZE(dva)	\
176 	BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0)
177 #define	DVA_SET_ASIZE(dva, x)	\
178 	BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \
179 	SPA_MINBLOCKSHIFT, 0, x)
180 
181 #define	DVA_GET_GRID(dva)	BF64_GET((dva)->dva_word[0], 24, 8)
182 #define	DVA_SET_GRID(dva, x)	BF64_SET((dva)->dva_word[0], 24, 8, x)
183 
184 #define	DVA_GET_VDEV(dva)	BF64_GET((dva)->dva_word[0], 32, 32)
185 #define	DVA_SET_VDEV(dva, x)	BF64_SET((dva)->dva_word[0], 32, 32, x)
186 
187 #define	DVA_GET_OFFSET(dva)	\
188 	BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
189 #define	DVA_SET_OFFSET(dva, x)	\
190 	BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
191 
192 #define	DVA_GET_GANG(dva)	BF64_GET((dva)->dva_word[1], 63, 1)
193 #define	DVA_SET_GANG(dva, x)	BF64_SET((dva)->dva_word[1], 63, 1, x)
194 
195 #define	BP_GET_LSIZE(bp)	\
196 	BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1)
197 #define	BP_SET_LSIZE(bp, x)	\
198 	BF64_SET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)
199 
200 #define	BP_GET_PSIZE(bp)	\
201 	BF64_GET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1)
202 #define	BP_SET_PSIZE(bp, x)	\
203 	BF64_SET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)
204 
205 #define	BP_GET_COMPRESS(bp)		BF64_GET((bp)->blk_prop, 32, 7)
206 #define	BP_SET_COMPRESS(bp, x)		BF64_SET((bp)->blk_prop, 32, 7, x)
207 
208 #define	BP_GET_CHECKSUM(bp)		BF64_GET((bp)->blk_prop, 40, 8)
209 #define	BP_SET_CHECKSUM(bp, x)		BF64_SET((bp)->blk_prop, 40, 8, x)
210 
211 #define	BP_GET_TYPE(bp)			BF64_GET((bp)->blk_prop, 48, 8)
212 #define	BP_SET_TYPE(bp, x)		BF64_SET((bp)->blk_prop, 48, 8, x)
213 
214 #define	BP_GET_LEVEL(bp)		BF64_GET((bp)->blk_prop, 56, 5)
215 #define	BP_SET_LEVEL(bp, x)		BF64_SET((bp)->blk_prop, 56, 5, x)
216 
217 #define	BP_IS_EMBEDDED(bp)		BF64_GET((bp)->blk_prop, 39, 1)
218 
219 #define	BP_GET_DEDUP(bp)		BF64_GET((bp)->blk_prop, 62, 1)
220 #define	BP_SET_DEDUP(bp, x)		BF64_SET((bp)->blk_prop, 62, 1, x)
221 
222 #define	BP_GET_BYTEORDER(bp)		BF64_GET((bp)->blk_prop, 63, 1)
223 #define	BP_SET_BYTEORDER(bp, x)		BF64_SET((bp)->blk_prop, 63, 1, x)
224 
225 #define	BP_PHYSICAL_BIRTH(bp)		\
226 	((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
227 
228 #define	BP_SET_BIRTH(bp, logical, physical)	\
229 {						\
230 	(bp)->blk_birth = (logical);		\
231 	(bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \
232 }
233 
234 #define	BP_GET_ASIZE(bp)	\
235 	(DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
236 		DVA_GET_ASIZE(&(bp)->blk_dva[2]))
237 
238 #define	BP_GET_UCSIZE(bp) \
239 	((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
240 	BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));
241 
242 #define	BP_GET_NDVAS(bp)	\
243 	(!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
244 	!!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
245 	!!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
246 
247 #define	DVA_EQUAL(dva1, dva2)	\
248 	((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
249 	(dva1)->dva_word[0] == (dva2)->dva_word[0])
250 
251 #define	BP_EQUAL(bp1, bp2)	\
252 	(BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) &&	\
253 	DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) &&	\
254 	DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) &&	\
255 	DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2]))
256 
257 #define	ZIO_CHECKSUM_EQUAL(zc1, zc2) \
258 	(0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
259 	((zc1).zc_word[1] - (zc2).zc_word[1]) | \
260 	((zc1).zc_word[2] - (zc2).zc_word[2]) | \
261 	((zc1).zc_word[3] - (zc2).zc_word[3])))
262 
263 #define	DVA_IS_VALID(dva)	(DVA_GET_ASIZE(dva) != 0)
264 
265 #define	ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)	\
266 {						\
267 	(zcp)->zc_word[0] = w0;			\
268 	(zcp)->zc_word[1] = w1;			\
269 	(zcp)->zc_word[2] = w2;			\
270 	(zcp)->zc_word[3] = w3;			\
271 }
272 
273 #define	BP_IDENTITY(bp)		(&(bp)->blk_dva[0])
274 #define	BP_IS_GANG(bp)		DVA_GET_GANG(BP_IDENTITY(bp))
275 #define	DVA_IS_EMPTY(dva)	((dva)->dva_word[0] == 0ULL &&	\
276 				(dva)->dva_word[1] == 0ULL)
277 #define	BP_IS_HOLE(bp)		DVA_IS_EMPTY(BP_IDENTITY(bp))
278 
279 /* BP_IS_RAIDZ(bp) assumes no block compression */
280 #define	BP_IS_RAIDZ(bp)		(DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \
281 				BP_GET_PSIZE(bp))
282 
283 #define	BP_ZERO(bp)				\
284 {						\
285 	(bp)->blk_dva[0].dva_word[0] = 0;	\
286 	(bp)->blk_dva[0].dva_word[1] = 0;	\
287 	(bp)->blk_dva[1].dva_word[0] = 0;	\
288 	(bp)->blk_dva[1].dva_word[1] = 0;	\
289 	(bp)->blk_dva[2].dva_word[0] = 0;	\
290 	(bp)->blk_dva[2].dva_word[1] = 0;	\
291 	(bp)->blk_prop = 0;			\
292 	(bp)->blk_pad[0] = 0;			\
293 	(bp)->blk_pad[1] = 0;			\
294 	(bp)->blk_phys_birth = 0;		\
295 	(bp)->blk_birth = 0;			\
296 	(bp)->blk_fill = 0;			\
297 	ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0);	\
298 }
299 
300 #define	BPE_GET_ETYPE(bp)	BP_GET_CHECKSUM(bp)
301 #define	BPE_GET_LSIZE(bp)	\
302 	BF64_GET_SB((bp)->blk_prop, 0, 25, 0, 1)
303 #define	BPE_GET_PSIZE(bp)	\
304 	BF64_GET_SB((bp)->blk_prop, 25, 7, 0, 1)
305 
306 typedef enum bp_embedded_type {
307 	BP_EMBEDDED_TYPE_DATA,
308 	NUM_BP_EMBEDDED_TYPES
309 } bp_embedded_type_t;
310 
311 #define	BPE_NUM_WORDS 14
312 #define	BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
313 #define	BPE_IS_PAYLOADWORD(bp, wp) \
314 	((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
315 
316 #ifdef _BIG_ENDIAN
317 #define	ZFS_HOST_BYTEORDER	(0ULL)
318 #else
319 #define	ZFS_HOST_BYTEORDER	(1ULL)
320 #endif
321 
322 #define	BP_SHOULD_BYTESWAP(bp)	(BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)
323 
324 #define	BP_SPRINTF_LEN	320
325 
326 #endif	/* _SYS_SPA_H */
327