xref: /freebsd/sys/cddl/boot/zfs/zfsimpl.h (revision 2f513db72b034fd5ef7f080b11be5c711c15186a)
1 /*-
2  * Copyright (c) 2002 McAfee, Inc.
3  * All rights reserved.
4  *
5  * This software was developed for the FreeBSD Project by Marshall
6  * Kirk McKusick and McAfee Research,, the Security Research Division of
7  * McAfee, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as
8  * part of the DARPA CHATS research program
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 /*
32  * CDDL HEADER START
33  *
34  * The contents of this file are subject to the terms of the
35  * Common Development and Distribution License (the "License").
36  * You may not use this file except in compliance with the License.
37  *
38  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
39  * or http://www.opensolaris.org/os/licensing.
40  * See the License for the specific language governing permissions
41  * and limitations under the License.
42  *
43  * When distributing Covered Code, include this CDDL HEADER in each
44  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
45  * If applicable, add the following below this CDDL HEADER, with the
46  * fields enclosed by brackets "[]" replaced with your own identifying
47  * information: Portions Copyright [yyyy] [name of copyright owner]
48  *
49  * CDDL HEADER END
50  */
51 /*
52  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
53  * Use is subject to license terms.
54  */
55 /*
56  * Copyright 2013 by Saso Kiselkov. All rights reserved.
57  */
58 /*
59  * Copyright (c) 2013 by Delphix. All rights reserved.
60  */
61 
62 #define	MAXNAMELEN	256
63 
64 #define _NOTE(s)
65 
66 /*
67  * AVL comparator helpers
68  */
69 #define	AVL_ISIGN(a)	(((a) > 0) - ((a) < 0))
70 #define	AVL_CMP(a, b)	(((a) > (b)) - ((a) < (b)))
71 #define	AVL_PCMP(a, b)	\
72 	(((uintptr_t)(a) > (uintptr_t)(b)) - ((uintptr_t)(a) < (uintptr_t)(b)))
73 
74 typedef enum { B_FALSE, B_TRUE } boolean_t;
75 
76 /* CRC64 table */
77 #define	ZFS_CRC64_POLY	0xC96C5795D7870F42ULL	/* ECMA-182, reflected form */
78 
79 /*
80  * Macros for various sorts of alignment and rounding when the alignment
81  * is known to be a power of 2.
82  */
83 #define	P2ALIGN(x, align)		((x) & -(align))
84 #define	P2PHASE(x, align)		((x) & ((align) - 1))
85 #define	P2NPHASE(x, align)		(-(x) & ((align) - 1))
86 #define	P2ROUNDUP(x, align)		(-(-(x) & -(align)))
87 #define	P2END(x, align)			(-(~(x) & -(align)))
88 #define	P2PHASEUP(x, align, phase)	((phase) - (((phase) - (x)) & -(align)))
89 #define	P2BOUNDARY(off, len, align)	(((off) ^ ((off) + (len) - 1)) > (align) - 1)
90 
91 /*
92  * General-purpose 32-bit and 64-bit bitfield encodings.
93  */
94 #define	BF32_DECODE(x, low, len)	P2PHASE((x) >> (low), 1U << (len))
95 #define	BF64_DECODE(x, low, len)	P2PHASE((x) >> (low), 1ULL << (len))
96 #define	BF32_ENCODE(x, low, len)	(P2PHASE((x), 1U << (len)) << (low))
97 #define	BF64_ENCODE(x, low, len)	(P2PHASE((x), 1ULL << (len)) << (low))
98 
99 #define	BF32_GET(x, low, len)		BF32_DECODE(x, low, len)
100 #define	BF64_GET(x, low, len)		BF64_DECODE(x, low, len)
101 
102 #define	BF32_SET(x, low, len, val)	\
103 	((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
104 #define	BF64_SET(x, low, len, val)	\
105 	((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))
106 
107 #define	BF32_GET_SB(x, low, len, shift, bias)	\
108 	((BF32_GET(x, low, len) + (bias)) << (shift))
109 #define	BF64_GET_SB(x, low, len, shift, bias)	\
110 	((BF64_GET(x, low, len) + (bias)) << (shift))
111 
112 #define	BF32_SET_SB(x, low, len, shift, bias, val)	\
113 	BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
114 #define	BF64_SET_SB(x, low, len, shift, bias, val)	\
115 	BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
116 
117 /*
118  * Macros to reverse byte order
119  */
120 #define	BSWAP_8(x)	((x) & 0xff)
121 #define	BSWAP_16(x)	((BSWAP_8(x) << 8) | BSWAP_8((x) >> 8))
122 #define	BSWAP_32(x)	((BSWAP_16(x) << 16) | BSWAP_16((x) >> 16))
123 #define	BSWAP_64(x)	((BSWAP_32(x) << 32) | BSWAP_32((x) >> 32))
124 
125 #define	SPA_MINBLOCKSHIFT	9
126 #define	SPA_OLDMAXBLOCKSHIFT	17
127 #define	SPA_MAXBLOCKSHIFT	24
128 #define	SPA_MINBLOCKSIZE	(1ULL << SPA_MINBLOCKSHIFT)
129 #define	SPA_OLDMAXBLOCKSIZE	(1ULL << SPA_OLDMAXBLOCKSHIFT)
130 #define	SPA_MAXBLOCKSIZE	(1ULL << SPA_MAXBLOCKSHIFT)
131 
132 /*
133  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
134  * The ASIZE encoding should be at least 64 times larger (6 more bits)
135  * to support up to 4-way RAID-Z mirror mode with worst-case gang block
136  * overhead, three DVAs per bp, plus one more bit in case we do anything
137  * else that expands the ASIZE.
138  */
139 #define	SPA_LSIZEBITS		16	/* LSIZE up to 32M (2^16 * 512)	*/
140 #define	SPA_PSIZEBITS		16	/* PSIZE up to 32M (2^16 * 512)	*/
141 #define	SPA_ASIZEBITS		24	/* ASIZE up to 64 times larger	*/
142 
143 /*
144  * All SPA data is represented by 128-bit data virtual addresses (DVAs).
145  * The members of the dva_t should be considered opaque outside the SPA.
146  */
147 typedef struct dva {
148 	uint64_t	dva_word[2];
149 } dva_t;
150 
151 /*
152  * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
153  */
154 typedef struct zio_cksum {
155 	uint64_t	zc_word[4];
156 } zio_cksum_t;
157 
158 /*
159  * Some checksums/hashes need a 256-bit initialization salt. This salt is kept
160  * secret and is suitable for use in MAC algorithms as the key.
161  */
162 typedef struct zio_cksum_salt {
163 	uint8_t		zcs_bytes[32];
164 } zio_cksum_salt_t;
165 
166 /*
167  * Each block is described by its DVAs, time of birth, checksum, etc.
168  * The word-by-word, bit-by-bit layout of the blkptr is as follows:
169  *
170  *	64	56	48	40	32	24	16	8	0
171  *	+-------+-------+-------+-------+-------+-------+-------+-------+
172  * 0	|		vdev1		| GRID  |	  ASIZE		|
173  *	+-------+-------+-------+-------+-------+-------+-------+-------+
174  * 1	|G|			 offset1				|
175  *	+-------+-------+-------+-------+-------+-------+-------+-------+
176  * 2	|		vdev2		| GRID  |	  ASIZE		|
177  *	+-------+-------+-------+-------+-------+-------+-------+-------+
178  * 3	|G|			 offset2				|
179  *	+-------+-------+-------+-------+-------+-------+-------+-------+
180  * 4	|		vdev3		| GRID  |	  ASIZE		|
181  *	+-------+-------+-------+-------+-------+-------+-------+-------+
182  * 5	|G|			 offset3				|
183  *	+-------+-------+-------+-------+-------+-------+-------+-------+
184  * 6	|BDX|lvl| type	| cksum |E| comp|    PSIZE	|     LSIZE	|
185  *	+-------+-------+-------+-------+-------+-------+-------+-------+
186  * 7	|			padding					|
187  *	+-------+-------+-------+-------+-------+-------+-------+-------+
188  * 8	|			padding					|
189  *	+-------+-------+-------+-------+-------+-------+-------+-------+
190  * 9	|			physical birth txg			|
191  *	+-------+-------+-------+-------+-------+-------+-------+-------+
192  * a	|			logical birth txg			|
193  *	+-------+-------+-------+-------+-------+-------+-------+-------+
194  * b	|			fill count				|
195  *	+-------+-------+-------+-------+-------+-------+-------+-------+
196  * c	|			checksum[0]				|
197  *	+-------+-------+-------+-------+-------+-------+-------+-------+
198  * d	|			checksum[1]				|
199  *	+-------+-------+-------+-------+-------+-------+-------+-------+
200  * e	|			checksum[2]				|
201  *	+-------+-------+-------+-------+-------+-------+-------+-------+
202  * f	|			checksum[3]				|
203  *	+-------+-------+-------+-------+-------+-------+-------+-------+
204  *
205  * Legend:
206  *
207  * vdev		virtual device ID
208  * offset	offset into virtual device
209  * LSIZE	logical size
210  * PSIZE	physical size (after compression)
211  * ASIZE	allocated size (including RAID-Z parity and gang block headers)
212  * GRID		RAID-Z layout information (reserved for future use)
213  * cksum	checksum function
214  * comp		compression function
215  * G		gang block indicator
216  * B		byteorder (endianness)
217  * D		dedup
218  * X		encryption (on version 30, which is not supported)
219  * E		blkptr_t contains embedded data (see below)
220  * lvl		level of indirection
221  * type		DMU object type
222  * phys birth	txg of block allocation; zero if same as logical birth txg
223  * log. birth	transaction group in which the block was logically born
224  * fill count	number of non-zero blocks under this bp
225  * checksum[4]	256-bit checksum of the data this bp describes
226  */
227 
228 /*
229  * "Embedded" blkptr_t's don't actually point to a block, instead they
230  * have a data payload embedded in the blkptr_t itself.  See the comment
231  * in blkptr.c for more details.
232  *
233  * The blkptr_t is laid out as follows:
234  *
235  *	64	56	48	40	32	24	16	8	0
236  *	+-------+-------+-------+-------+-------+-------+-------+-------+
237  * 0	|      payload                                                  |
238  * 1	|      payload                                                  |
239  * 2	|      payload                                                  |
240  * 3	|      payload                                                  |
241  * 4	|      payload                                                  |
242  * 5	|      payload                                                  |
243  *	+-------+-------+-------+-------+-------+-------+-------+-------+
244  * 6	|BDX|lvl| type	| etype |E| comp| PSIZE|              LSIZE	|
245  *	+-------+-------+-------+-------+-------+-------+-------+-------+
246  * 7	|      payload                                                  |
247  * 8	|      payload                                                  |
248  * 9	|      payload                                                  |
249  *	+-------+-------+-------+-------+-------+-------+-------+-------+
250  * a	|			logical birth txg			|
251  *	+-------+-------+-------+-------+-------+-------+-------+-------+
252  * b	|      payload                                                  |
253  * c	|      payload                                                  |
254  * d	|      payload                                                  |
255  * e	|      payload                                                  |
256  * f	|      payload                                                  |
257  *	+-------+-------+-------+-------+-------+-------+-------+-------+
258  *
259  * Legend:
260  *
261  * payload		contains the embedded data
262  * B (byteorder)	byteorder (endianness)
263  * D (dedup)		padding (set to zero)
264  * X			encryption (set to zero; see above)
265  * E (embedded)		set to one
266  * lvl			indirection level
267  * type			DMU object type
268  * etype		how to interpret embedded data (BP_EMBEDDED_TYPE_*)
269  * comp			compression function of payload
270  * PSIZE		size of payload after compression, in bytes
271  * LSIZE		logical size of payload, in bytes
272  *			note that 25 bits is enough to store the largest
273  *			"normal" BP's LSIZE (2^16 * 2^9) in bytes
274  * log. birth		transaction group in which the block was logically born
275  *
276  * Note that LSIZE and PSIZE are stored in bytes, whereas for non-embedded
277  * bp's they are stored in units of SPA_MINBLOCKSHIFT.
278  * Generally, the generic BP_GET_*() macros can be used on embedded BP's.
279  * The B, D, X, lvl, type, and comp fields are stored the same as with normal
280  * BP's so the BP_SET_* macros can be used with them.  etype, PSIZE, LSIZE must
281  * be set with the BPE_SET_* macros.  BP_SET_EMBEDDED() should be called before
282  * other macros, as they assert that they are only used on BP's of the correct
283  * "embedded-ness".
284  */
285 
286 #define	BPE_GET_ETYPE(bp)	\
287 	(ASSERT(BP_IS_EMBEDDED(bp)), \
288 	BF64_GET((bp)->blk_prop, 40, 8))
289 #define	BPE_SET_ETYPE(bp, t)	do { \
290 	ASSERT(BP_IS_EMBEDDED(bp)); \
291 	BF64_SET((bp)->blk_prop, 40, 8, t); \
292 _NOTE(CONSTCOND) } while (0)
293 
294 #define	BPE_GET_LSIZE(bp)	\
295 	(ASSERT(BP_IS_EMBEDDED(bp)), \
296 	BF64_GET_SB((bp)->blk_prop, 0, 25, 0, 1))
297 #define	BPE_SET_LSIZE(bp, x)	do { \
298 	ASSERT(BP_IS_EMBEDDED(bp)); \
299 	BF64_SET_SB((bp)->blk_prop, 0, 25, 0, 1, x); \
300 _NOTE(CONSTCOND) } while (0)
301 
302 #define	BPE_GET_PSIZE(bp)	\
303 	(ASSERT(BP_IS_EMBEDDED(bp)), \
304 	BF64_GET_SB((bp)->blk_prop, 25, 7, 0, 1))
305 #define	BPE_SET_PSIZE(bp, x)	do { \
306 	ASSERT(BP_IS_EMBEDDED(bp)); \
307 	BF64_SET_SB((bp)->blk_prop, 25, 7, 0, 1, x); \
308 _NOTE(CONSTCOND) } while (0)
309 
310 typedef enum bp_embedded_type {
311 	BP_EMBEDDED_TYPE_DATA,
312 	BP_EMBEDDED_TYPE_RESERVED, /* Reserved for an unintegrated feature. */
313 	NUM_BP_EMBEDDED_TYPES = BP_EMBEDDED_TYPE_RESERVED
314 } bp_embedded_type_t;
315 
316 #define	BPE_NUM_WORDS 14
317 #define	BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
318 #define	BPE_IS_PAYLOADWORD(bp, wp) \
319 	((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
320 
321 #define	SPA_BLKPTRSHIFT	7		/* blkptr_t is 128 bytes	*/
322 #define	SPA_DVAS_PER_BP	3		/* Number of DVAs in a bp	*/
323 
324 typedef struct blkptr {
325 	dva_t		blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
326 	uint64_t	blk_prop;	/* size, compression, type, etc	    */
327 	uint64_t	blk_pad[2];	/* Extra space for the future	    */
328 	uint64_t	blk_phys_birth;	/* txg when block was allocated	    */
329 	uint64_t	blk_birth;	/* transaction group at birth	    */
330 	uint64_t	blk_fill;	/* fill count			    */
331 	zio_cksum_t	blk_cksum;	/* 256-bit checksum		    */
332 } blkptr_t;
333 
334 /*
335  * Macros to get and set fields in a bp or DVA.
336  */
337 #define	DVA_GET_ASIZE(dva)	\
338 	BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0)
339 #define	DVA_SET_ASIZE(dva, x)	\
340 	BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \
341 	SPA_MINBLOCKSHIFT, 0, x)
342 
343 #define	DVA_GET_GRID(dva)	BF64_GET((dva)->dva_word[0], 24, 8)
344 #define	DVA_SET_GRID(dva, x)	BF64_SET((dva)->dva_word[0], 24, 8, x)
345 
346 #define	DVA_GET_VDEV(dva)	BF64_GET((dva)->dva_word[0], 32, 32)
347 #define	DVA_SET_VDEV(dva, x)	BF64_SET((dva)->dva_word[0], 32, 32, x)
348 
349 #define	DVA_GET_OFFSET(dva)	\
350 	BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
351 #define	DVA_SET_OFFSET(dva, x)	\
352 	BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
353 
354 #define	DVA_GET_GANG(dva)	BF64_GET((dva)->dva_word[1], 63, 1)
355 #define	DVA_SET_GANG(dva, x)	BF64_SET((dva)->dva_word[1], 63, 1, x)
356 
357 #define	BP_GET_LSIZE(bp)	\
358 	(BP_IS_EMBEDDED(bp) ?	\
359 	(BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA ? BPE_GET_LSIZE(bp) : 0): \
360 	BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1))
361 #define	BP_SET_LSIZE(bp, x)	do { \
362 	ASSERT(!BP_IS_EMBEDDED(bp)); \
363 	BF64_SET_SB((bp)->blk_prop, \
364 	    0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x); \
365 _NOTE(CONSTCOND) } while (0)
366 
367 #define	BP_GET_PSIZE(bp)	\
368 	BF64_GET_SB((bp)->blk_prop, 16, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1)
369 #define	BP_SET_PSIZE(bp, x)	\
370 	BF64_SET_SB((bp)->blk_prop, 16, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)
371 
372 #define	BP_GET_COMPRESS(bp)	BF64_GET((bp)->blk_prop, 32, 7)
373 #define	BP_SET_COMPRESS(bp, x)	BF64_SET((bp)->blk_prop, 32, 7, x)
374 
375 #define	BP_GET_CHECKSUM(bp)	BF64_GET((bp)->blk_prop, 40, 8)
376 #define	BP_SET_CHECKSUM(bp, x)	BF64_SET((bp)->blk_prop, 40, 8, x)
377 
378 #define	BP_GET_TYPE(bp)		BF64_GET((bp)->blk_prop, 48, 8)
379 #define	BP_SET_TYPE(bp, x)	BF64_SET((bp)->blk_prop, 48, 8, x)
380 
381 #define	BP_GET_LEVEL(bp)	BF64_GET((bp)->blk_prop, 56, 5)
382 #define	BP_SET_LEVEL(bp, x)	BF64_SET((bp)->blk_prop, 56, 5, x)
383 
384 #define	BP_IS_EMBEDDED(bp)	BF64_GET((bp)->blk_prop, 39, 1)
385 
386 #define	BP_GET_DEDUP(bp)	BF64_GET((bp)->blk_prop, 62, 1)
387 #define	BP_SET_DEDUP(bp, x)	BF64_SET((bp)->blk_prop, 62, 1, x)
388 
389 #define	BP_GET_BYTEORDER(bp)	BF64_GET((bp)->blk_prop, 63, 1)
390 #define	BP_SET_BYTEORDER(bp, x)	BF64_SET((bp)->blk_prop, 63, 1, x)
391 
392 #define	BP_PHYSICAL_BIRTH(bp)		\
393 	((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
394 
395 #define	BP_GET_ASIZE(bp)	\
396 	(DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
397 		DVA_GET_ASIZE(&(bp)->blk_dva[2]))
398 
399 #define	BP_GET_UCSIZE(bp) \
400 	((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
401 	BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));
402 
403 #define	BP_GET_NDVAS(bp)	\
404 	(!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
405 	!!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
406 	!!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
407 
408 #define	DVA_EQUAL(dva1, dva2)	\
409 	((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
410 	(dva1)->dva_word[0] == (dva2)->dva_word[0])
411 
412 #define	ZIO_CHECKSUM_EQUAL(zc1, zc2) \
413 	(0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
414 	((zc1).zc_word[1] - (zc2).zc_word[1]) | \
415 	((zc1).zc_word[2] - (zc2).zc_word[2]) | \
416 	((zc1).zc_word[3] - (zc2).zc_word[3])))
417 
418 
419 #define	DVA_IS_VALID(dva)	(DVA_GET_ASIZE(dva) != 0)
420 
421 #define	ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)	\
422 {						\
423 	(zcp)->zc_word[0] = w0;			\
424 	(zcp)->zc_word[1] = w1;			\
425 	(zcp)->zc_word[2] = w2;			\
426 	(zcp)->zc_word[3] = w3;			\
427 }
428 
429 #define	BP_IDENTITY(bp)		(&(bp)->blk_dva[0])
430 #define	BP_IS_GANG(bp)		DVA_GET_GANG(BP_IDENTITY(bp))
431 #define	DVA_IS_EMPTY(dva)	((dva)->dva_word[0] == 0ULL &&  \
432 	(dva)->dva_word[1] == 0ULL)
433 #define	BP_IS_HOLE(bp)		DVA_IS_EMPTY(BP_IDENTITY(bp))
434 #define	BP_IS_OLDER(bp, txg)	(!BP_IS_HOLE(bp) && (bp)->blk_birth < (txg))
435 
436 #define	BP_ZERO(bp)				\
437 {						\
438 	(bp)->blk_dva[0].dva_word[0] = 0;	\
439 	(bp)->blk_dva[0].dva_word[1] = 0;	\
440 	(bp)->blk_dva[1].dva_word[0] = 0;	\
441 	(bp)->blk_dva[1].dva_word[1] = 0;	\
442 	(bp)->blk_dva[2].dva_word[0] = 0;	\
443 	(bp)->blk_dva[2].dva_word[1] = 0;	\
444 	(bp)->blk_prop = 0;			\
445 	(bp)->blk_pad[0] = 0;			\
446 	(bp)->blk_pad[1] = 0;			\
447 	(bp)->blk_phys_birth = 0;		\
448 	(bp)->blk_birth = 0;			\
449 	(bp)->blk_fill = 0;			\
450 	ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0);	\
451 }
452 
453 #if BYTE_ORDER == _BIG_ENDIAN
454 #define	ZFS_HOST_BYTEORDER	(0ULL)
455 #else
456 #define	ZFS_HOST_BYTEORDER	(1ULL)
457 #endif
458 
459 #define	BP_SHOULD_BYTESWAP(bp)	(BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)
460 #define	BPE_NUM_WORDS 14
461 #define	BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
462 #define	BPE_IS_PAYLOADWORD(bp, wp) \
463 	((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
464 
465 /*
466  * Embedded checksum
467  */
468 #define	ZEC_MAGIC	0x210da7ab10c7a11ULL
469 
470 typedef struct zio_eck {
471 	uint64_t	zec_magic;	/* for validation, endianness	*/
472 	zio_cksum_t	zec_cksum;	/* 256-bit checksum		*/
473 } zio_eck_t;
474 
475 /*
476  * Gang block headers are self-checksumming and contain an array
477  * of block pointers.
478  */
479 #define	SPA_GANGBLOCKSIZE	SPA_MINBLOCKSIZE
480 #define	SPA_GBH_NBLKPTRS	((SPA_GANGBLOCKSIZE - \
481 	sizeof (zio_eck_t)) / sizeof (blkptr_t))
482 #define	SPA_GBH_FILLER		((SPA_GANGBLOCKSIZE - \
483 	sizeof (zio_eck_t) - \
484 	(SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
485 	sizeof (uint64_t))
486 
487 typedef struct zio_gbh {
488 	blkptr_t		zg_blkptr[SPA_GBH_NBLKPTRS];
489 	uint64_t		zg_filler[SPA_GBH_FILLER];
490 	zio_eck_t		zg_tail;
491 } zio_gbh_phys_t;
492 
493 #define	VDEV_RAIDZ_MAXPARITY	3
494 
495 #define	VDEV_PAD_SIZE		(8 << 10)
496 /* 2 padding areas (vl_pad1 and vl_pad2) to skip */
497 #define	VDEV_SKIP_SIZE		VDEV_PAD_SIZE * 2
498 #define	VDEV_PHYS_SIZE		(112 << 10)
499 #define	VDEV_UBERBLOCK_RING	(128 << 10)
500 
501 /*
502  * MMP blocks occupy the last MMP_BLOCKS_PER_LABEL slots in the uberblock
503  * ring when MMP is enabled.
504  */
505 #define	MMP_BLOCKS_PER_LABEL	1
506 
507 /* The largest uberblock we support is 8k. */
508 #define	MAX_UBERBLOCK_SHIFT	(13)
509 #define	VDEV_UBERBLOCK_SHIFT(vd)	\
510 	MIN(MAX((vd)->v_top->v_ashift, UBERBLOCK_SHIFT), MAX_UBERBLOCK_SHIFT)
511 #define	VDEV_UBERBLOCK_COUNT(vd)	\
512 	(VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
513 #define	VDEV_UBERBLOCK_OFFSET(vd, n)	\
514 	offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
515 #define	VDEV_UBERBLOCK_SIZE(vd)		(1ULL << VDEV_UBERBLOCK_SHIFT(vd))
516 
517 typedef struct vdev_phys {
518 	char		vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_eck_t)];
519 	zio_eck_t	vp_zbt;
520 } vdev_phys_t;
521 
522 typedef struct vdev_label {
523 	char		vl_pad1[VDEV_PAD_SIZE];			/*  8K  */
524 	char		vl_pad2[VDEV_PAD_SIZE];			/*  8K  */
525 	vdev_phys_t	vl_vdev_phys;				/* 112K	*/
526 	char		vl_uberblock[VDEV_UBERBLOCK_RING];	/* 128K	*/
527 } vdev_label_t;							/* 256K total */
528 
529 /*
530  * vdev_dirty() flags
531  */
532 #define	VDD_METASLAB	0x01
533 #define	VDD_DTL		0x02
534 
535 /*
536  * Size and offset of embedded boot loader region on each label.
537  * The total size of the first two labels plus the boot area is 4MB.
538  */
539 #define	VDEV_BOOT_OFFSET	(2 * sizeof (vdev_label_t))
540 #define	VDEV_BOOT_SIZE		(7ULL << 19)			/* 3.5M	*/
541 
542 /*
543  * Size of label regions at the start and end of each leaf device.
544  */
545 #define	VDEV_LABEL_START_SIZE	(2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
546 #define	VDEV_LABEL_END_SIZE	(2 * sizeof (vdev_label_t))
547 #define	VDEV_LABELS		4
548 
549 enum zio_checksum {
550 	ZIO_CHECKSUM_INHERIT = 0,
551 	ZIO_CHECKSUM_ON,
552 	ZIO_CHECKSUM_OFF,
553 	ZIO_CHECKSUM_LABEL,
554 	ZIO_CHECKSUM_GANG_HEADER,
555 	ZIO_CHECKSUM_ZILOG,
556 	ZIO_CHECKSUM_FLETCHER_2,
557 	ZIO_CHECKSUM_FLETCHER_4,
558 	ZIO_CHECKSUM_SHA256,
559 	ZIO_CHECKSUM_ZILOG2,
560 	ZIO_CHECKSUM_NOPARITY,
561 	ZIO_CHECKSUM_SHA512,
562 	ZIO_CHECKSUM_SKEIN,
563 	ZIO_CHECKSUM_EDONR,
564 	ZIO_CHECKSUM_FUNCTIONS
565 };
566 
567 #define	ZIO_CHECKSUM_ON_VALUE	ZIO_CHECKSUM_FLETCHER_4
568 #define	ZIO_CHECKSUM_DEFAULT	ZIO_CHECKSUM_ON
569 
570 enum zio_compress {
571 	ZIO_COMPRESS_INHERIT = 0,
572 	ZIO_COMPRESS_ON,
573 	ZIO_COMPRESS_OFF,
574 	ZIO_COMPRESS_LZJB,
575 	ZIO_COMPRESS_EMPTY,
576 	ZIO_COMPRESS_GZIP_1,
577 	ZIO_COMPRESS_GZIP_2,
578 	ZIO_COMPRESS_GZIP_3,
579 	ZIO_COMPRESS_GZIP_4,
580 	ZIO_COMPRESS_GZIP_5,
581 	ZIO_COMPRESS_GZIP_6,
582 	ZIO_COMPRESS_GZIP_7,
583 	ZIO_COMPRESS_GZIP_8,
584 	ZIO_COMPRESS_GZIP_9,
585 	ZIO_COMPRESS_ZLE,
586 	ZIO_COMPRESS_LZ4,
587 	ZIO_COMPRESS_FUNCTIONS
588 };
589 
590 #define	ZIO_COMPRESS_ON_VALUE	ZIO_COMPRESS_LZJB
591 #define	ZIO_COMPRESS_DEFAULT	ZIO_COMPRESS_OFF
592 
593 /* nvlist pack encoding */
594 #define	NV_ENCODE_NATIVE	0
595 #define	NV_ENCODE_XDR		1
596 
597 typedef enum {
598 	DATA_TYPE_UNKNOWN = 0,
599 	DATA_TYPE_BOOLEAN,
600 	DATA_TYPE_BYTE,
601 	DATA_TYPE_INT16,
602 	DATA_TYPE_UINT16,
603 	DATA_TYPE_INT32,
604 	DATA_TYPE_UINT32,
605 	DATA_TYPE_INT64,
606 	DATA_TYPE_UINT64,
607 	DATA_TYPE_STRING,
608 	DATA_TYPE_BYTE_ARRAY,
609 	DATA_TYPE_INT16_ARRAY,
610 	DATA_TYPE_UINT16_ARRAY,
611 	DATA_TYPE_INT32_ARRAY,
612 	DATA_TYPE_UINT32_ARRAY,
613 	DATA_TYPE_INT64_ARRAY,
614 	DATA_TYPE_UINT64_ARRAY,
615 	DATA_TYPE_STRING_ARRAY,
616 	DATA_TYPE_HRTIME,
617 	DATA_TYPE_NVLIST,
618 	DATA_TYPE_NVLIST_ARRAY,
619 	DATA_TYPE_BOOLEAN_VALUE,
620 	DATA_TYPE_INT8,
621 	DATA_TYPE_UINT8,
622 	DATA_TYPE_BOOLEAN_ARRAY,
623 	DATA_TYPE_INT8_ARRAY,
624 	DATA_TYPE_UINT8_ARRAY
625 } data_type_t;
626 
627 /*
628  * On-disk version number.
629  */
630 #define	SPA_VERSION_1			1ULL
631 #define	SPA_VERSION_2			2ULL
632 #define	SPA_VERSION_3			3ULL
633 #define	SPA_VERSION_4			4ULL
634 #define	SPA_VERSION_5			5ULL
635 #define	SPA_VERSION_6			6ULL
636 #define	SPA_VERSION_7			7ULL
637 #define	SPA_VERSION_8			8ULL
638 #define	SPA_VERSION_9			9ULL
639 #define	SPA_VERSION_10			10ULL
640 #define	SPA_VERSION_11			11ULL
641 #define	SPA_VERSION_12			12ULL
642 #define	SPA_VERSION_13			13ULL
643 #define	SPA_VERSION_14			14ULL
644 #define	SPA_VERSION_15			15ULL
645 #define	SPA_VERSION_16			16ULL
646 #define	SPA_VERSION_17			17ULL
647 #define	SPA_VERSION_18			18ULL
648 #define	SPA_VERSION_19			19ULL
649 #define	SPA_VERSION_20			20ULL
650 #define	SPA_VERSION_21			21ULL
651 #define	SPA_VERSION_22			22ULL
652 #define	SPA_VERSION_23			23ULL
653 #define	SPA_VERSION_24			24ULL
654 #define	SPA_VERSION_25			25ULL
655 #define	SPA_VERSION_26			26ULL
656 #define	SPA_VERSION_27			27ULL
657 #define	SPA_VERSION_28			28ULL
658 #define	SPA_VERSION_5000		5000ULL
659 
660 /*
661  * When bumping up SPA_VERSION, make sure GRUB ZFS understands the on-disk
662  * format change. Go to usr/src/grub/grub-0.97/stage2/{zfs-include/, fsys_zfs*},
663  * and do the appropriate changes.  Also bump the version number in
664  * usr/src/grub/capability.
665  */
666 #define	SPA_VERSION			SPA_VERSION_5000
667 #define	SPA_VERSION_STRING		"5000"
668 
669 /*
670  * Symbolic names for the changes that caused a SPA_VERSION switch.
671  * Used in the code when checking for presence or absence of a feature.
672  * Feel free to define multiple symbolic names for each version if there
673  * were multiple changes to on-disk structures during that version.
674  *
675  * NOTE: When checking the current SPA_VERSION in your code, be sure
676  *       to use spa_version() since it reports the version of the
677  *       last synced uberblock.  Checking the in-flight version can
678  *       be dangerous in some cases.
679  */
680 #define	SPA_VERSION_INITIAL		SPA_VERSION_1
681 #define	SPA_VERSION_DITTO_BLOCKS	SPA_VERSION_2
682 #define	SPA_VERSION_SPARES		SPA_VERSION_3
683 #define	SPA_VERSION_RAID6		SPA_VERSION_3
684 #define	SPA_VERSION_BPLIST_ACCOUNT	SPA_VERSION_3
685 #define	SPA_VERSION_RAIDZ_DEFLATE	SPA_VERSION_3
686 #define	SPA_VERSION_DNODE_BYTES		SPA_VERSION_3
687 #define	SPA_VERSION_ZPOOL_HISTORY	SPA_VERSION_4
688 #define	SPA_VERSION_GZIP_COMPRESSION	SPA_VERSION_5
689 #define	SPA_VERSION_BOOTFS		SPA_VERSION_6
690 #define	SPA_VERSION_SLOGS		SPA_VERSION_7
691 #define	SPA_VERSION_DELEGATED_PERMS	SPA_VERSION_8
692 #define	SPA_VERSION_FUID		SPA_VERSION_9
693 #define	SPA_VERSION_REFRESERVATION	SPA_VERSION_9
694 #define	SPA_VERSION_REFQUOTA		SPA_VERSION_9
695 #define	SPA_VERSION_UNIQUE_ACCURATE	SPA_VERSION_9
696 #define	SPA_VERSION_L2CACHE		SPA_VERSION_10
697 #define	SPA_VERSION_NEXT_CLONES		SPA_VERSION_11
698 #define	SPA_VERSION_ORIGIN		SPA_VERSION_11
699 #define	SPA_VERSION_DSL_SCRUB		SPA_VERSION_11
700 #define	SPA_VERSION_SNAP_PROPS		SPA_VERSION_12
701 #define	SPA_VERSION_USED_BREAKDOWN	SPA_VERSION_13
702 #define	SPA_VERSION_PASSTHROUGH_X	SPA_VERSION_14
703 #define SPA_VERSION_USERSPACE		SPA_VERSION_15
704 #define	SPA_VERSION_STMF_PROP		SPA_VERSION_16
705 #define	SPA_VERSION_RAIDZ3		SPA_VERSION_17
706 #define	SPA_VERSION_USERREFS		SPA_VERSION_18
707 #define	SPA_VERSION_HOLES		SPA_VERSION_19
708 #define	SPA_VERSION_ZLE_COMPRESSION	SPA_VERSION_20
709 #define	SPA_VERSION_DEDUP		SPA_VERSION_21
710 #define	SPA_VERSION_RECVD_PROPS		SPA_VERSION_22
711 #define	SPA_VERSION_SLIM_ZIL		SPA_VERSION_23
712 #define	SPA_VERSION_SA			SPA_VERSION_24
713 #define	SPA_VERSION_SCAN		SPA_VERSION_25
714 #define	SPA_VERSION_DIR_CLONES		SPA_VERSION_26
715 #define	SPA_VERSION_DEADLISTS		SPA_VERSION_26
716 #define	SPA_VERSION_FAST_SNAP		SPA_VERSION_27
717 #define	SPA_VERSION_MULTI_REPLACE	SPA_VERSION_28
718 #define	SPA_VERSION_BEFORE_FEATURES	SPA_VERSION_28
719 #define	SPA_VERSION_FEATURES		SPA_VERSION_5000
720 
721 #define	SPA_VERSION_IS_SUPPORTED(v) \
722 	(((v) >= SPA_VERSION_INITIAL && (v) <= SPA_VERSION_BEFORE_FEATURES) || \
723 	((v) >= SPA_VERSION_FEATURES && (v) <= SPA_VERSION))
724 
725 /*
726  * The following are configuration names used in the nvlist describing a pool's
727  * configuration.
728  */
729 #define	ZPOOL_CONFIG_VERSION		"version"
730 #define	ZPOOL_CONFIG_POOL_NAME		"name"
731 #define	ZPOOL_CONFIG_POOL_STATE		"state"
732 #define	ZPOOL_CONFIG_POOL_TXG		"txg"
733 #define	ZPOOL_CONFIG_POOL_GUID		"pool_guid"
734 #define	ZPOOL_CONFIG_CREATE_TXG		"create_txg"
735 #define	ZPOOL_CONFIG_TOP_GUID		"top_guid"
736 #define	ZPOOL_CONFIG_VDEV_TREE		"vdev_tree"
737 #define	ZPOOL_CONFIG_TYPE		"type"
738 #define	ZPOOL_CONFIG_CHILDREN		"children"
739 #define	ZPOOL_CONFIG_ID			"id"
740 #define	ZPOOL_CONFIG_GUID		"guid"
741 #define	ZPOOL_CONFIG_INDIRECT_OBJECT	"com.delphix:indirect_object"
742 #define	ZPOOL_CONFIG_INDIRECT_BIRTHS	"com.delphix:indirect_births"
743 #define	ZPOOL_CONFIG_PREV_INDIRECT_VDEV	"com.delphix:prev_indirect_vdev"
744 #define	ZPOOL_CONFIG_PATH		"path"
745 #define	ZPOOL_CONFIG_DEVID		"devid"
746 #define	ZPOOL_CONFIG_METASLAB_ARRAY	"metaslab_array"
747 #define	ZPOOL_CONFIG_METASLAB_SHIFT	"metaslab_shift"
748 #define	ZPOOL_CONFIG_ASHIFT		"ashift"
749 #define	ZPOOL_CONFIG_ASIZE		"asize"
750 #define	ZPOOL_CONFIG_DTL		"DTL"
751 #define	ZPOOL_CONFIG_STATS		"stats"
752 #define	ZPOOL_CONFIG_WHOLE_DISK		"whole_disk"
753 #define	ZPOOL_CONFIG_ERRCOUNT		"error_count"
754 #define	ZPOOL_CONFIG_NOT_PRESENT	"not_present"
755 #define	ZPOOL_CONFIG_SPARES		"spares"
756 #define	ZPOOL_CONFIG_IS_SPARE		"is_spare"
757 #define	ZPOOL_CONFIG_NPARITY		"nparity"
758 #define	ZPOOL_CONFIG_HOSTID		"hostid"
759 #define	ZPOOL_CONFIG_HOSTNAME		"hostname"
760 #define	ZPOOL_CONFIG_IS_LOG		"is_log"
761 #define	ZPOOL_CONFIG_TIMESTAMP		"timestamp" /* not stored on disk */
762 #define	ZPOOL_CONFIG_FEATURES_FOR_READ	"features_for_read"
763 #define	ZPOOL_CONFIG_VDEV_CHILDREN	"vdev_children"
764 
765 /*
766  * The persistent vdev state is stored as separate values rather than a single
767  * 'vdev_state' entry.  This is because a device can be in multiple states, such
768  * as offline and degraded.
769  */
770 #define	ZPOOL_CONFIG_OFFLINE            "offline"
771 #define	ZPOOL_CONFIG_FAULTED            "faulted"
772 #define	ZPOOL_CONFIG_DEGRADED           "degraded"
773 #define	ZPOOL_CONFIG_REMOVED            "removed"
774 #define	ZPOOL_CONFIG_FRU		"fru"
775 #define	ZPOOL_CONFIG_AUX_STATE		"aux_state"
776 
777 #define	VDEV_TYPE_ROOT			"root"
778 #define	VDEV_TYPE_MIRROR		"mirror"
779 #define	VDEV_TYPE_REPLACING		"replacing"
780 #define	VDEV_TYPE_RAIDZ			"raidz"
781 #define	VDEV_TYPE_DISK			"disk"
782 #define	VDEV_TYPE_FILE			"file"
783 #define	VDEV_TYPE_MISSING		"missing"
784 #define	VDEV_TYPE_HOLE			"hole"
785 #define	VDEV_TYPE_SPARE			"spare"
786 #define	VDEV_TYPE_LOG			"log"
787 #define	VDEV_TYPE_L2CACHE		"l2cache"
788 #define	VDEV_TYPE_INDIRECT		"indirect"
789 
790 /*
791  * This is needed in userland to report the minimum necessary device size.
792  */
793 #define	SPA_MINDEVSIZE		(64ULL << 20)
794 
795 /*
796  * The location of the pool configuration repository, shared between kernel and
797  * userland.
798  */
799 #define	ZPOOL_CACHE		"/boot/zfs/zpool.cache"
800 
801 /*
802  * vdev states are ordered from least to most healthy.
803  * A vdev that's CANT_OPEN or below is considered unusable.
804  */
805 typedef enum vdev_state {
806 	VDEV_STATE_UNKNOWN = 0,	/* Uninitialized vdev			*/
807 	VDEV_STATE_CLOSED,	/* Not currently open			*/
808 	VDEV_STATE_OFFLINE,	/* Not allowed to open			*/
809 	VDEV_STATE_REMOVED,	/* Explicitly removed from system	*/
810 	VDEV_STATE_CANT_OPEN,	/* Tried to open, but failed		*/
811 	VDEV_STATE_FAULTED,	/* External request to fault device	*/
812 	VDEV_STATE_DEGRADED,	/* Replicated vdev with unhealthy kids	*/
813 	VDEV_STATE_HEALTHY	/* Presumed good			*/
814 } vdev_state_t;
815 
816 /*
817  * vdev aux states.  When a vdev is in the CANT_OPEN state, the aux field
818  * of the vdev stats structure uses these constants to distinguish why.
819  */
820 typedef enum vdev_aux {
821 	VDEV_AUX_NONE,		/* no error				*/
822 	VDEV_AUX_OPEN_FAILED,	/* ldi_open_*() or vn_open() failed	*/
823 	VDEV_AUX_CORRUPT_DATA,	/* bad label or disk contents		*/
824 	VDEV_AUX_NO_REPLICAS,	/* insufficient number of replicas	*/
825 	VDEV_AUX_BAD_GUID_SUM,	/* vdev guid sum doesn't match		*/
826 	VDEV_AUX_TOO_SMALL,	/* vdev size is too small		*/
827 	VDEV_AUX_BAD_LABEL,	/* the label is OK but invalid		*/
828 	VDEV_AUX_VERSION_NEWER,	/* on-disk version is too new		*/
829 	VDEV_AUX_VERSION_OLDER,	/* on-disk version is too old		*/
830 	VDEV_AUX_SPARED		/* hot spare used in another pool	*/
831 } vdev_aux_t;
832 
833 /*
834  * pool state.  The following states are written to disk as part of the normal
835  * SPA lifecycle: ACTIVE, EXPORTED, DESTROYED, SPARE.  The remaining states are
836  * software abstractions used at various levels to communicate pool state.
837  */
838 typedef enum pool_state {
839 	POOL_STATE_ACTIVE = 0,		/* In active use		*/
840 	POOL_STATE_EXPORTED,		/* Explicitly exported		*/
841 	POOL_STATE_DESTROYED,		/* Explicitly destroyed		*/
842 	POOL_STATE_SPARE,		/* Reserved for hot spare use	*/
843 	POOL_STATE_UNINITIALIZED,	/* Internal spa_t state		*/
844 	POOL_STATE_UNAVAIL,		/* Internal libzfs state	*/
845 	POOL_STATE_POTENTIALLY_ACTIVE	/* Internal libzfs state	*/
846 } pool_state_t;
847 
848 /*
849  * The uberblock version is incremented whenever an incompatible on-disk
850  * format change is made to the SPA, DMU, or ZAP.
851  *
852  * Note: the first two fields should never be moved.  When a storage pool
853  * is opened, the uberblock must be read off the disk before the version
854  * can be checked.  If the ub_version field is moved, we may not detect
855  * version mismatch.  If the ub_magic field is moved, applications that
856  * expect the magic number in the first word won't work.
857  */
858 #define	UBERBLOCK_MAGIC		0x00bab10c		/* oo-ba-bloc!	*/
859 #define	UBERBLOCK_SHIFT		10			/* up to 1K	*/
860 
861 #define	MMP_MAGIC		0xa11cea11		/* all-see-all  */
862 
863 #define	MMP_INTERVAL_VALID_BIT	0x01
864 #define	MMP_SEQ_VALID_BIT	0x02
865 #define	MMP_FAIL_INT_VALID_BIT	0x04
866 
867 #define	MMP_VALID(ubp)		(ubp->ub_magic == UBERBLOCK_MAGIC && \
868 				    ubp->ub_mmp_magic == MMP_MAGIC)
869 #define	MMP_INTERVAL_VALID(ubp)	(MMP_VALID(ubp) && (ubp->ub_mmp_config & \
870 				    MMP_INTERVAL_VALID_BIT))
871 #define	MMP_SEQ_VALID(ubp)	(MMP_VALID(ubp) && (ubp->ub_mmp_config & \
872 				    MMP_SEQ_VALID_BIT))
873 #define	MMP_FAIL_INT_VALID(ubp)	(MMP_VALID(ubp) && (ubp->ub_mmp_config & \
874 				    MMP_FAIL_INT_VALID_BIT))
875 
876 #define	MMP_INTERVAL(ubp)	((ubp->ub_mmp_config & 0x00000000FFFFFF00) \
877 				    >> 8)
878 #define	MMP_SEQ(ubp)		((ubp->ub_mmp_config & 0x0000FFFF00000000) \
879 				    >> 32)
880 #define	MMP_FAIL_INT(ubp)	((ubp->ub_mmp_config & 0xFFFF000000000000) \
881 				    >> 48)
882 
883 typedef struct uberblock {
884 	uint64_t	ub_magic;	/* UBERBLOCK_MAGIC		*/
885 	uint64_t	ub_version;	/* SPA_VERSION			*/
886 	uint64_t	ub_txg;		/* txg of last sync		*/
887 	uint64_t	ub_guid_sum;	/* sum of all vdev guids	*/
888 	uint64_t	ub_timestamp;	/* UTC time of last sync	*/
889 	blkptr_t	ub_rootbp;	/* MOS objset_phys_t		*/
890 	/* highest SPA_VERSION supported by software that wrote this txg */
891 	uint64_t	ub_software_version;
892 	/* Maybe missing in uberblocks we read, but always written */
893 	uint64_t	ub_mmp_magic;
894 	/*
895 	 * If ub_mmp_delay == 0 and ub_mmp_magic is valid, MMP is off.
896 	 * Otherwise, nanosec since last MMP write.
897 	 */
898 	uint64_t	ub_mmp_delay;
899 
900 	/*
901 	 * The ub_mmp_config contains the multihost write interval, multihost
902 	 * fail intervals, sequence number for sub-second granularity, and
903 	 * valid bit mask.  This layout is as follows:
904 	 *
905 	 *   64      56      48      40      32      24      16      8       0
906 	 *   +-------+-------+-------+-------+-------+-------+-------+-------+
907 	 * 0 | Fail Intervals|      Seq      |   Write Interval (ms) | VALID |
908 	 *   +-------+-------+-------+-------+-------+-------+-------+-------+
909 	 *
910 	 * This allows a write_interval of (2^24/1000)s, over 4.5 hours
911 	 *
912 	 * VALID Bits:
913 	 * - 0x01 - Write Interval (ms)
914 	 * - 0x02 - Sequence number exists
915 	 * - 0x04 - Fail Intervals
916 	 * - 0xf8 - Reserved
917 	 */
918 	uint64_t	ub_mmp_config;
919 
920 	/*
921 	 * ub_checkpoint_txg indicates two things about the current uberblock:
922 	 *
923 	 * 1] If it is not zero then this uberblock is a checkpoint. If it is
924 	 *    zero, then this uberblock is not a checkpoint.
925 	 *
926 	 * 2] On checkpointed uberblocks, the value of ub_checkpoint_txg is
927 	 *    the ub_txg that the uberblock had at the time we moved it to
928 	 *    the MOS config.
929 	 *
930 	 * The field is set when we checkpoint the uberblock and continues to
931 	 * hold that value even after we've rewound (unlike the ub_txg that
932 	 * is reset to a higher value).
933 	 *
934 	 * Besides checks used to determine whether we are reopening the
935 	 * pool from a checkpointed uberblock [see spa_ld_select_uberblock()],
936 	 * the value of the field is used to determine which ZIL blocks have
937 	 * been allocated according to the ms_sm when we are rewinding to a
938 	 * checkpoint. Specifically, if blk_birth > ub_checkpoint_txg, then
939 	 * the ZIL block is not allocated [see uses of spa_min_claim_txg()].
940 	 */
941 	uint64_t	ub_checkpoint_txg;
942 } uberblock_t;
943 
944 /*
945  * Flags.
946  */
947 #define	DNODE_MUST_BE_ALLOCATED	1
948 #define	DNODE_MUST_BE_FREE	2
949 
950 /*
951  * Fixed constants.
952  */
953 #define	DNODE_SHIFT		9	/* 512 bytes */
954 #define	DN_MIN_INDBLKSHIFT	12	/* 4k */
955 #define	DN_MAX_INDBLKSHIFT	17	/* 128k */
956 #define	DNODE_BLOCK_SHIFT	14	/* 16k */
957 #define	DNODE_CORE_SIZE		64	/* 64 bytes for dnode sans blkptrs */
958 #define	DN_MAX_OBJECT_SHIFT	48	/* 256 trillion (zfs_fid_t limit) */
959 #define	DN_MAX_OFFSET_SHIFT	64	/* 2^64 bytes in a dnode */
960 
961 /*
962  * Derived constants.
963  */
964 #define	DNODE_MIN_SIZE		(1 << DNODE_SHIFT)
965 #define	DNODE_MAX_SIZE		(1 << DNODE_BLOCK_SHIFT)
966 #define	DNODE_BLOCK_SIZE	(1 << DNODE_BLOCK_SHIFT)
967 #define	DNODE_MIN_SLOTS		(DNODE_MIN_SIZE >> DNODE_SHIFT)
968 #define	DNODE_MAX_SLOTS		(DNODE_MAX_SIZE >> DNODE_SHIFT)
969 #define	DN_BONUS_SIZE(dnsize)	((dnsize) - DNODE_CORE_SIZE - \
970 	(1 << SPA_BLKPTRSHIFT))
971 #define	DN_SLOTS_TO_BONUSLEN(slots)	DN_BONUS_SIZE((slots) << DNODE_SHIFT)
972 #define	DN_OLD_MAX_BONUSLEN		(DN_BONUS_SIZE(DNODE_MIN_SIZE))
973 #define	DN_MAX_NBLKPTR		((DNODE_MIN_SIZE - DNODE_CORE_SIZE) >> \
974 	SPA_BLKPTRSHIFT)
975 #define	DN_MAX_OBJECT		(1ULL << DN_MAX_OBJECT_SHIFT)
976 #define	DN_ZERO_BONUSLEN	(DN_BONUS_SIZE(DNODE_MAX_SIZE) + 1)
977 
978 #define	DNODES_PER_BLOCK_SHIFT	(DNODE_BLOCK_SHIFT - DNODE_SHIFT)
979 #define	DNODES_PER_BLOCK	(1ULL << DNODES_PER_BLOCK_SHIFT)
980 #define	DNODES_PER_LEVEL_SHIFT	(DN_MAX_INDBLKSHIFT - SPA_BLKPTRSHIFT)
981 
982 /* The +2 here is a cheesy way to round up */
983 #define	DN_MAX_LEVELS	(2 + ((DN_MAX_OFFSET_SHIFT - SPA_MINBLOCKSHIFT) / \
984 	(DN_MIN_INDBLKSHIFT - SPA_BLKPTRSHIFT)))
985 
986 #define	DN_BONUS(dnp)	((void*)((dnp)->dn_bonus + \
987 	(((dnp)->dn_nblkptr - 1) * sizeof (blkptr_t))))
988 
989 #define	DN_USED_BYTES(dnp) (((dnp)->dn_flags & DNODE_FLAG_USED_BYTES) ? \
990 	(dnp)->dn_used : (dnp)->dn_used << SPA_MINBLOCKSHIFT)
991 
992 #define	EPB(blkshift, typeshift)	(1 << (blkshift - typeshift))
993 
994 /* Is dn_used in bytes?  if not, it's in multiples of SPA_MINBLOCKSIZE */
995 #define	DNODE_FLAG_USED_BYTES		(1<<0)
996 #define	DNODE_FLAG_USERUSED_ACCOUNTED	(1<<1)
997 
998 /* Does dnode have a SA spill blkptr in bonus? */
999 #define	DNODE_FLAG_SPILL_BLKPTR	(1<<2)
1000 
1001 typedef struct dnode_phys {
1002 	uint8_t dn_type;		/* dmu_object_type_t */
1003 	uint8_t dn_indblkshift;		/* ln2(indirect block size) */
1004 	uint8_t dn_nlevels;		/* 1=dn_blkptr->data blocks */
1005 	uint8_t dn_nblkptr;		/* length of dn_blkptr */
1006 	uint8_t dn_bonustype;		/* type of data in bonus buffer */
1007 	uint8_t	dn_checksum;		/* ZIO_CHECKSUM type */
1008 	uint8_t	dn_compress;		/* ZIO_COMPRESS type */
1009 	uint8_t dn_flags;		/* DNODE_FLAG_* */
1010 	uint16_t dn_datablkszsec;	/* data block size in 512b sectors */
1011 	uint16_t dn_bonuslen;		/* length of dn_bonus */
1012 	uint8_t dn_extra_slots;		/* # of subsequent slots consumed */
1013 	uint8_t dn_pad2[3];
1014 
1015 	/* accounting is protected by dn_dirty_mtx */
1016 	uint64_t dn_maxblkid;		/* largest allocated block ID */
1017 	uint64_t dn_used;		/* bytes (or sectors) of disk space */
1018 
1019 	uint64_t dn_pad3[4];
1020 
1021 	/*
1022 	 * The tail region is 448 bytes for a 512 byte dnode, and
1023 	 * correspondingly larger for larger dnode sizes. The spill
1024 	 * block pointer, when present, is always at the end of the tail
1025 	 * region. There are three ways this space may be used, using
1026 	 * a 512 byte dnode for this diagram:
1027 	 *
1028 	 * 0       64      128     192     256     320     384     448 (offset)
1029 	 * +---------------+---------------+---------------+-------+
1030 	 * | dn_blkptr[0]  | dn_blkptr[1]  | dn_blkptr[2]  | /     |
1031 	 * +---------------+---------------+---------------+-------+
1032 	 * | dn_blkptr[0]  | dn_bonus[0..319]                      |
1033 	 * +---------------+-----------------------+---------------+
1034 	 * | dn_blkptr[0]  | dn_bonus[0..191]      | dn_spill      |
1035 	 * +---------------+-----------------------+---------------+
1036 	 */
1037 	union {
1038 		blkptr_t dn_blkptr[1+DN_OLD_MAX_BONUSLEN/sizeof (blkptr_t)];
1039 		struct {
1040 			blkptr_t __dn_ignore1;
1041 			uint8_t dn_bonus[DN_OLD_MAX_BONUSLEN];
1042 		};
1043 		struct {
1044 			blkptr_t __dn_ignore2;
1045 			uint8_t __dn_ignore3[DN_OLD_MAX_BONUSLEN -
1046 			    sizeof (blkptr_t)];
1047 			blkptr_t dn_spill;
1048 		};
1049 	};
1050 } dnode_phys_t;
1051 
1052 #define	DN_SPILL_BLKPTR(dnp)	(blkptr_t *)((char *)(dnp) + \
1053 	(((dnp)->dn_extra_slots + 1) << DNODE_SHIFT) - (1 << SPA_BLKPTRSHIFT))
1054 
1055 typedef enum dmu_object_byteswap {
1056 	DMU_BSWAP_UINT8,
1057 	DMU_BSWAP_UINT16,
1058 	DMU_BSWAP_UINT32,
1059 	DMU_BSWAP_UINT64,
1060 	DMU_BSWAP_ZAP,
1061 	DMU_BSWAP_DNODE,
1062 	DMU_BSWAP_OBJSET,
1063 	DMU_BSWAP_ZNODE,
1064 	DMU_BSWAP_OLDACL,
1065 	DMU_BSWAP_ACL,
1066 	/*
1067 	 * Allocating a new byteswap type number makes the on-disk format
1068 	 * incompatible with any other format that uses the same number.
1069 	 *
1070 	 * Data can usually be structured to work with one of the
1071 	 * DMU_BSWAP_UINT* or DMU_BSWAP_ZAP types.
1072 	 */
1073 	DMU_BSWAP_NUMFUNCS
1074 } dmu_object_byteswap_t;
1075 
1076 #define	DMU_OT_NEWTYPE 0x80
1077 #define	DMU_OT_METADATA 0x40
1078 #define	DMU_OT_BYTESWAP_MASK 0x3f
1079 
1080 /*
1081  * Defines a uint8_t object type. Object types specify if the data
1082  * in the object is metadata (boolean) and how to byteswap the data
1083  * (dmu_object_byteswap_t).
1084  */
1085 #define	DMU_OT(byteswap, metadata) \
1086 	(DMU_OT_NEWTYPE | \
1087 	((metadata) ? DMU_OT_METADATA : 0) | \
1088 	((byteswap) & DMU_OT_BYTESWAP_MASK))
1089 
1090 typedef enum dmu_object_type {
1091 	DMU_OT_NONE,
1092 	/* general: */
1093 	DMU_OT_OBJECT_DIRECTORY,	/* ZAP */
1094 	DMU_OT_OBJECT_ARRAY,		/* UINT64 */
1095 	DMU_OT_PACKED_NVLIST,		/* UINT8 (XDR by nvlist_pack/unpack) */
1096 	DMU_OT_PACKED_NVLIST_SIZE,	/* UINT64 */
1097 	DMU_OT_BPLIST,			/* UINT64 */
1098 	DMU_OT_BPLIST_HDR,		/* UINT64 */
1099 	/* spa: */
1100 	DMU_OT_SPACE_MAP_HEADER,	/* UINT64 */
1101 	DMU_OT_SPACE_MAP,		/* UINT64 */
1102 	/* zil: */
1103 	DMU_OT_INTENT_LOG,		/* UINT64 */
1104 	/* dmu: */
1105 	DMU_OT_DNODE,			/* DNODE */
1106 	DMU_OT_OBJSET,			/* OBJSET */
1107 	/* dsl: */
1108 	DMU_OT_DSL_DIR,			/* UINT64 */
1109 	DMU_OT_DSL_DIR_CHILD_MAP,	/* ZAP */
1110 	DMU_OT_DSL_DS_SNAP_MAP,		/* ZAP */
1111 	DMU_OT_DSL_PROPS,		/* ZAP */
1112 	DMU_OT_DSL_DATASET,		/* UINT64 */
1113 	/* zpl: */
1114 	DMU_OT_ZNODE,			/* ZNODE */
1115 	DMU_OT_OLDACL,			/* Old ACL */
1116 	DMU_OT_PLAIN_FILE_CONTENTS,	/* UINT8 */
1117 	DMU_OT_DIRECTORY_CONTENTS,	/* ZAP */
1118 	DMU_OT_MASTER_NODE,		/* ZAP */
1119 	DMU_OT_UNLINKED_SET,		/* ZAP */
1120 	/* zvol: */
1121 	DMU_OT_ZVOL,			/* UINT8 */
1122 	DMU_OT_ZVOL_PROP,		/* ZAP */
1123 	/* other; for testing only! */
1124 	DMU_OT_PLAIN_OTHER,		/* UINT8 */
1125 	DMU_OT_UINT64_OTHER,		/* UINT64 */
1126 	DMU_OT_ZAP_OTHER,		/* ZAP */
1127 	/* new object types: */
1128 	DMU_OT_ERROR_LOG,		/* ZAP */
1129 	DMU_OT_SPA_HISTORY,		/* UINT8 */
1130 	DMU_OT_SPA_HISTORY_OFFSETS,	/* spa_his_phys_t */
1131 	DMU_OT_POOL_PROPS,		/* ZAP */
1132 	DMU_OT_DSL_PERMS,		/* ZAP */
1133 	DMU_OT_ACL,			/* ACL */
1134 	DMU_OT_SYSACL,			/* SYSACL */
1135 	DMU_OT_FUID,			/* FUID table (Packed NVLIST UINT8) */
1136 	DMU_OT_FUID_SIZE,		/* FUID table size UINT64 */
1137 	DMU_OT_NEXT_CLONES,		/* ZAP */
1138 	DMU_OT_SCAN_QUEUE,		/* ZAP */
1139 	DMU_OT_USERGROUP_USED,		/* ZAP */
1140 	DMU_OT_USERGROUP_QUOTA,		/* ZAP */
1141 	DMU_OT_USERREFS,		/* ZAP */
1142 	DMU_OT_DDT_ZAP,			/* ZAP */
1143 	DMU_OT_DDT_STATS,		/* ZAP */
1144 	DMU_OT_SA,			/* System attr */
1145 	DMU_OT_SA_MASTER_NODE,		/* ZAP */
1146 	DMU_OT_SA_ATTR_REGISTRATION,	/* ZAP */
1147 	DMU_OT_SA_ATTR_LAYOUTS,		/* ZAP */
1148 	DMU_OT_SCAN_XLATE,		/* ZAP */
1149 	DMU_OT_DEDUP,			/* fake dedup BP from ddt_bp_create() */
1150 	DMU_OT_NUMTYPES,
1151 
1152 	/*
1153 	 * Names for valid types declared with DMU_OT().
1154 	 */
1155 	DMU_OTN_UINT8_DATA = DMU_OT(DMU_BSWAP_UINT8, B_FALSE),
1156 	DMU_OTN_UINT8_METADATA = DMU_OT(DMU_BSWAP_UINT8, B_TRUE),
1157 	DMU_OTN_UINT16_DATA = DMU_OT(DMU_BSWAP_UINT16, B_FALSE),
1158 	DMU_OTN_UINT16_METADATA = DMU_OT(DMU_BSWAP_UINT16, B_TRUE),
1159 	DMU_OTN_UINT32_DATA = DMU_OT(DMU_BSWAP_UINT32, B_FALSE),
1160 	DMU_OTN_UINT32_METADATA = DMU_OT(DMU_BSWAP_UINT32, B_TRUE),
1161 	DMU_OTN_UINT64_DATA = DMU_OT(DMU_BSWAP_UINT64, B_FALSE),
1162 	DMU_OTN_UINT64_METADATA = DMU_OT(DMU_BSWAP_UINT64, B_TRUE),
1163 	DMU_OTN_ZAP_DATA = DMU_OT(DMU_BSWAP_ZAP, B_FALSE),
1164 	DMU_OTN_ZAP_METADATA = DMU_OT(DMU_BSWAP_ZAP, B_TRUE)
1165 } dmu_object_type_t;
1166 
1167 typedef enum dmu_objset_type {
1168 	DMU_OST_NONE,
1169 	DMU_OST_META,
1170 	DMU_OST_ZFS,
1171 	DMU_OST_ZVOL,
1172 	DMU_OST_OTHER,			/* For testing only! */
1173 	DMU_OST_ANY,			/* Be careful! */
1174 	DMU_OST_NUMTYPES
1175 } dmu_objset_type_t;
1176 
1177 #define	ZAP_MAXVALUELEN	(1024 * 8)
1178 
1179 /*
1180  * header for all bonus and spill buffers.
1181  * The header has a fixed portion with a variable number
1182  * of "lengths" depending on the number of variable sized
1183  * attribues which are determined by the "layout number"
1184  */
1185 
1186 #define	SA_MAGIC	0x2F505A  /* ZFS SA */
1187 typedef struct sa_hdr_phys {
1188 	uint32_t sa_magic;
1189 	uint16_t sa_layout_info;  /* Encoded with hdrsize and layout number */
1190 	uint16_t sa_lengths[1];	/* optional sizes for variable length attrs */
1191 	/* ... Data follows the lengths.  */
1192 } sa_hdr_phys_t;
1193 
1194 /*
1195  * sa_hdr_phys -> sa_layout_info
1196  *
1197  * 16      10       0
1198  * +--------+-------+
1199  * | hdrsz  |layout |
1200  * +--------+-------+
1201  *
1202  * Bits 0-10 are the layout number
1203  * Bits 11-16 are the size of the header.
1204  * The hdrsize is the number * 8
1205  *
1206  * For example.
1207  * hdrsz of 1 ==> 8 byte header
1208  *          2 ==> 16 byte header
1209  *
1210  */
1211 
1212 #define	SA_HDR_LAYOUT_NUM(hdr) BF32_GET(hdr->sa_layout_info, 0, 10)
1213 #define	SA_HDR_SIZE(hdr) BF32_GET_SB(hdr->sa_layout_info, 10, 16, 3, 0)
1214 #define	SA_HDR_LAYOUT_INFO_ENCODE(x, num, size) \
1215 { \
1216 	BF32_SET_SB(x, 10, 6, 3, 0, size); \
1217 	BF32_SET(x, 0, 10, num); \
1218 }
1219 
1220 #define	SA_MODE_OFFSET		0
1221 #define	SA_SIZE_OFFSET		8
1222 #define	SA_GEN_OFFSET		16
1223 #define	SA_UID_OFFSET		24
1224 #define	SA_GID_OFFSET		32
1225 #define	SA_PARENT_OFFSET	40
1226 #define	SA_SYMLINK_OFFSET	160
1227 
1228 #define	ZIO_OBJSET_MAC_LEN		32
1229 
1230 /*
1231  * Intent log header - this on disk structure holds fields to manage
1232  * the log.  All fields are 64 bit to easily handle cross architectures.
1233  */
1234 typedef struct zil_header {
1235 	uint64_t zh_claim_txg;	/* txg in which log blocks were claimed */
1236 	uint64_t zh_replay_seq;	/* highest replayed sequence number */
1237 	blkptr_t zh_log;	/* log chain */
1238 	uint64_t zh_claim_seq;	/* highest claimed sequence number */
1239 	uint64_t zh_pad[5];
1240 } zil_header_t;
1241 
1242 #define	OBJSET_PHYS_SIZE_V2 2048
1243 #define	OBJSET_PHYS_SIZE_V3 4096
1244 
1245 typedef struct objset_phys {
1246 	dnode_phys_t os_meta_dnode;
1247 	zil_header_t os_zil_header;
1248 	uint64_t os_type;
1249 	uint64_t os_flags;
1250 	uint8_t os_portable_mac[ZIO_OBJSET_MAC_LEN];
1251 	uint8_t os_local_mac[ZIO_OBJSET_MAC_LEN];
1252 	char os_pad0[OBJSET_PHYS_SIZE_V2 - sizeof (dnode_phys_t)*3 -
1253 		sizeof (zil_header_t) - sizeof (uint64_t)*2 -
1254 		2*ZIO_OBJSET_MAC_LEN];
1255 	dnode_phys_t os_userused_dnode;
1256 	dnode_phys_t os_groupused_dnode;
1257 	dnode_phys_t os_projectused_dnode;
1258 	char os_pad1[OBJSET_PHYS_SIZE_V3 - OBJSET_PHYS_SIZE_V2 -
1259 	    sizeof (dnode_phys_t)];
1260 } objset_phys_t;
1261 
1262 typedef struct dsl_dir_phys {
1263 	uint64_t dd_creation_time; /* not actually used */
1264 	uint64_t dd_head_dataset_obj;
1265 	uint64_t dd_parent_obj;
1266 	uint64_t dd_clone_parent_obj;
1267 	uint64_t dd_child_dir_zapobj;
1268 	/*
1269 	 * how much space our children are accounting for; for leaf
1270 	 * datasets, == physical space used by fs + snaps
1271 	 */
1272 	uint64_t dd_used_bytes;
1273 	uint64_t dd_compressed_bytes;
1274 	uint64_t dd_uncompressed_bytes;
1275 	/* Administrative quota setting */
1276 	uint64_t dd_quota;
1277 	/* Administrative reservation setting */
1278 	uint64_t dd_reserved;
1279 	uint64_t dd_props_zapobj;
1280 	uint64_t dd_pad[21]; /* pad out to 256 bytes for good measure */
1281 } dsl_dir_phys_t;
1282 
1283 typedef struct dsl_dataset_phys {
1284 	uint64_t ds_dir_obj;
1285 	uint64_t ds_prev_snap_obj;
1286 	uint64_t ds_prev_snap_txg;
1287 	uint64_t ds_next_snap_obj;
1288 	uint64_t ds_snapnames_zapobj;	/* zap obj of snaps; ==0 for snaps */
1289 	uint64_t ds_num_children;	/* clone/snap children; ==0 for head */
1290 	uint64_t ds_creation_time;	/* seconds since 1970 */
1291 	uint64_t ds_creation_txg;
1292 	uint64_t ds_deadlist_obj;
1293 	uint64_t ds_used_bytes;
1294 	uint64_t ds_compressed_bytes;
1295 	uint64_t ds_uncompressed_bytes;
1296 	uint64_t ds_unique_bytes;	/* only relevant to snapshots */
1297 	/*
1298 	 * The ds_fsid_guid is a 56-bit ID that can change to avoid
1299 	 * collisions.  The ds_guid is a 64-bit ID that will never
1300 	 * change, so there is a small probability that it will collide.
1301 	 */
1302 	uint64_t ds_fsid_guid;
1303 	uint64_t ds_guid;
1304 	uint64_t ds_flags;
1305 	blkptr_t ds_bp;
1306 	uint64_t ds_pad[8]; /* pad out to 320 bytes for good measure */
1307 } dsl_dataset_phys_t;
1308 
1309 /*
1310  * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
1311  */
1312 #define	DMU_POOL_DIRECTORY_OBJECT	1
1313 #define	DMU_POOL_CONFIG			"config"
1314 #define	DMU_POOL_FEATURES_FOR_READ	"features_for_read"
1315 #define	DMU_POOL_ROOT_DATASET		"root_dataset"
1316 #define	DMU_POOL_SYNC_BPLIST		"sync_bplist"
1317 #define	DMU_POOL_ERRLOG_SCRUB		"errlog_scrub"
1318 #define	DMU_POOL_ERRLOG_LAST		"errlog_last"
1319 #define	DMU_POOL_SPARES			"spares"
1320 #define	DMU_POOL_DEFLATE		"deflate"
1321 #define	DMU_POOL_HISTORY		"history"
1322 #define	DMU_POOL_PROPS			"pool_props"
1323 #define	DMU_POOL_CHECKSUM_SALT		"org.illumos:checksum_salt"
1324 #define	DMU_POOL_REMOVING		"com.delphix:removing"
1325 #define	DMU_POOL_OBSOLETE_BPOBJ		"com.delphix:obsolete_bpobj"
1326 #define	DMU_POOL_CONDENSING_INDIRECT	"com.delphix:condensing_indirect"
1327 
1328 #define	ZAP_MAGIC 0x2F52AB2ABULL
1329 
1330 #define	FZAP_BLOCK_SHIFT(zap)	((zap)->zap_block_shift)
1331 
1332 #define	ZAP_MAXCD		(uint32_t)(-1)
1333 #define	ZAP_HASHBITS		28
1334 #define	MZAP_ENT_LEN		64
1335 #define	MZAP_NAME_LEN		(MZAP_ENT_LEN - 8 - 4 - 2)
1336 #define	MZAP_MAX_BLKSZ		SPA_OLD_MAXBLOCKSIZE
1337 
1338 typedef struct mzap_ent_phys {
1339 	uint64_t mze_value;
1340 	uint32_t mze_cd;
1341 	uint16_t mze_pad;	/* in case we want to chain them someday */
1342 	char mze_name[MZAP_NAME_LEN];
1343 } mzap_ent_phys_t;
1344 
1345 typedef struct mzap_phys {
1346 	uint64_t mz_block_type;	/* ZBT_MICRO */
1347 	uint64_t mz_salt;
1348 	uint64_t mz_normflags;
1349 	uint64_t mz_pad[5];
1350 	mzap_ent_phys_t mz_chunk[1];
1351 	/* actually variable size depending on block size */
1352 } mzap_phys_t;
1353 
1354 /*
1355  * The (fat) zap is stored in one object. It is an array of
1356  * 1<<FZAP_BLOCK_SHIFT byte blocks. The layout looks like one of:
1357  *
1358  * ptrtbl fits in first block:
1359  * 	[zap_phys_t zap_ptrtbl_shift < 6] [zap_leaf_t] ...
1360  *
1361  * ptrtbl too big for first block:
1362  * 	[zap_phys_t zap_ptrtbl_shift >= 6] [zap_leaf_t] [ptrtbl] ...
1363  *
1364  */
1365 
1366 #define	ZBT_LEAF		((1ULL << 63) + 0)
1367 #define	ZBT_HEADER		((1ULL << 63) + 1)
1368 #define	ZBT_MICRO		((1ULL << 63) + 3)
1369 /* any other values are ptrtbl blocks */
1370 
1371 /*
1372  * the embedded pointer table takes up half a block:
1373  * block size / entry size (2^3) / 2
1374  */
1375 #define	ZAP_EMBEDDED_PTRTBL_SHIFT(zap) (FZAP_BLOCK_SHIFT(zap) - 3 - 1)
1376 
1377 /*
1378  * The embedded pointer table starts half-way through the block.  Since
1379  * the pointer table itself is half the block, it starts at (64-bit)
1380  * word number (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)).
1381  */
1382 #define	ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) \
1383 	((uint64_t *)(zap)->zap_phys) \
1384 	[(idx) + (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap))]
1385 
1386 /*
1387  * TAKE NOTE:
1388  * If zap_phys_t is modified, zap_byteswap() must be modified.
1389  */
1390 typedef struct zap_phys {
1391 	uint64_t zap_block_type;	/* ZBT_HEADER */
1392 	uint64_t zap_magic;		/* ZAP_MAGIC */
1393 
1394 	struct zap_table_phys {
1395 		uint64_t zt_blk;	/* starting block number */
1396 		uint64_t zt_numblks;	/* number of blocks */
1397 		uint64_t zt_shift;	/* bits to index it */
1398 		uint64_t zt_nextblk;	/* next (larger) copy start block */
1399 		uint64_t zt_blks_copied; /* number source blocks copied */
1400 	} zap_ptrtbl;
1401 
1402 	uint64_t zap_freeblk;		/* the next free block */
1403 	uint64_t zap_num_leafs;		/* number of leafs */
1404 	uint64_t zap_num_entries;	/* number of entries */
1405 	uint64_t zap_salt;		/* salt to stir into hash function */
1406 	uint64_t zap_normflags;		/* flags for u8_textprep_str() */
1407 	uint64_t zap_flags;		/* zap_flags_t */
1408 	/*
1409 	 * This structure is followed by padding, and then the embedded
1410 	 * pointer table.  The embedded pointer table takes up second
1411 	 * half of the block.  It is accessed using the
1412 	 * ZAP_EMBEDDED_PTRTBL_ENT() macro.
1413 	 */
1414 } zap_phys_t;
1415 
1416 typedef struct zap_table_phys zap_table_phys_t;
1417 
1418 struct spa;
1419 typedef struct fat_zap {
1420 	int zap_block_shift;			/* block size shift */
1421 	zap_phys_t *zap_phys;
1422 	const struct spa *zap_spa;
1423 	const dnode_phys_t *zap_dnode;
1424 } fat_zap_t;
1425 
1426 #define	ZAP_LEAF_MAGIC 0x2AB1EAF
1427 
1428 /* chunk size = 24 bytes */
1429 #define	ZAP_LEAF_CHUNKSIZE 24
1430 
1431 /*
1432  * The amount of space available for chunks is:
1433  * block size (1<<l->l_bs) - hash entry size (2) * number of hash
1434  * entries - header space (2*chunksize)
1435  */
1436 #define	ZAP_LEAF_NUMCHUNKS(l) \
1437 	(((1<<(l)->l_bs) - 2*ZAP_LEAF_HASH_NUMENTRIES(l)) / \
1438 	ZAP_LEAF_CHUNKSIZE - 2)
1439 
1440 /*
1441  * The amount of space within the chunk available for the array is:
1442  * chunk size - space for type (1) - space for next pointer (2)
1443  */
1444 #define	ZAP_LEAF_ARRAY_BYTES (ZAP_LEAF_CHUNKSIZE - 3)
1445 
1446 #define	ZAP_LEAF_ARRAY_NCHUNKS(bytes) \
1447 	(((bytes)+ZAP_LEAF_ARRAY_BYTES-1)/ZAP_LEAF_ARRAY_BYTES)
1448 
1449 /*
1450  * Low water mark:  when there are only this many chunks free, start
1451  * growing the ptrtbl.  Ideally, this should be larger than a
1452  * "reasonably-sized" entry.  20 chunks is more than enough for the
1453  * largest directory entry (MAXNAMELEN (256) byte name, 8-byte value),
1454  * while still being only around 3% for 16k blocks.
1455  */
1456 #define	ZAP_LEAF_LOW_WATER (20)
1457 
1458 /*
1459  * The leaf hash table has block size / 2^5 (32) number of entries,
1460  * which should be more than enough for the maximum number of entries,
1461  * which is less than block size / CHUNKSIZE (24) / minimum number of
1462  * chunks per entry (3).
1463  */
1464 #define	ZAP_LEAF_HASH_SHIFT(l) ((l)->l_bs - 5)
1465 #define	ZAP_LEAF_HASH_NUMENTRIES(l) (1 << ZAP_LEAF_HASH_SHIFT(l))
1466 
1467 /*
1468  * The chunks start immediately after the hash table.  The end of the
1469  * hash table is at l_hash + HASH_NUMENTRIES, which we simply cast to a
1470  * chunk_t.
1471  */
1472 #define	ZAP_LEAF_CHUNK(l, idx) \
1473 	((zap_leaf_chunk_t *) \
1474 	((l)->l_phys->l_hash + ZAP_LEAF_HASH_NUMENTRIES(l)))[idx]
1475 #define	ZAP_LEAF_ENTRY(l, idx) (&ZAP_LEAF_CHUNK(l, idx).l_entry)
1476 
1477 typedef enum zap_chunk_type {
1478 	ZAP_CHUNK_FREE = 253,
1479 	ZAP_CHUNK_ENTRY = 252,
1480 	ZAP_CHUNK_ARRAY = 251,
1481 	ZAP_CHUNK_TYPE_MAX = 250
1482 } zap_chunk_type_t;
1483 
1484 /*
1485  * TAKE NOTE:
1486  * If zap_leaf_phys_t is modified, zap_leaf_byteswap() must be modified.
1487  */
1488 typedef struct zap_leaf_phys {
1489 	struct zap_leaf_header {
1490 		uint64_t lh_block_type;		/* ZBT_LEAF */
1491 		uint64_t lh_pad1;
1492 		uint64_t lh_prefix;		/* hash prefix of this leaf */
1493 		uint32_t lh_magic;		/* ZAP_LEAF_MAGIC */
1494 		uint16_t lh_nfree;		/* number free chunks */
1495 		uint16_t lh_nentries;		/* number of entries */
1496 		uint16_t lh_prefix_len;		/* num bits used to id this */
1497 
1498 /* above is accessable to zap, below is zap_leaf private */
1499 
1500 		uint16_t lh_freelist;		/* chunk head of free list */
1501 		uint8_t lh_pad2[12];
1502 	} l_hdr; /* 2 24-byte chunks */
1503 
1504 	/*
1505 	 * The header is followed by a hash table with
1506 	 * ZAP_LEAF_HASH_NUMENTRIES(zap) entries.  The hash table is
1507 	 * followed by an array of ZAP_LEAF_NUMCHUNKS(zap)
1508 	 * zap_leaf_chunk structures.  These structures are accessed
1509 	 * with the ZAP_LEAF_CHUNK() macro.
1510 	 */
1511 
1512 	uint16_t l_hash[1];
1513 } zap_leaf_phys_t;
1514 
1515 typedef union zap_leaf_chunk {
1516 	struct zap_leaf_entry {
1517 		uint8_t le_type; 		/* always ZAP_CHUNK_ENTRY */
1518 		uint8_t le_value_intlen;	/* size of ints */
1519 		uint16_t le_next;		/* next entry in hash chain */
1520 		uint16_t le_name_chunk;		/* first chunk of the name */
1521 		uint16_t le_name_numints;	/* bytes in name, incl null */
1522 		uint16_t le_value_chunk;	/* first chunk of the value */
1523 		uint16_t le_value_numints;	/* value length in ints */
1524 		uint32_t le_cd;			/* collision differentiator */
1525 		uint64_t le_hash;		/* hash value of the name */
1526 	} l_entry;
1527 	struct zap_leaf_array {
1528 		uint8_t la_type;		/* always ZAP_CHUNK_ARRAY */
1529 		uint8_t la_array[ZAP_LEAF_ARRAY_BYTES];
1530 		uint16_t la_next;		/* next blk or CHAIN_END */
1531 	} l_array;
1532 	struct zap_leaf_free {
1533 		uint8_t lf_type;		/* always ZAP_CHUNK_FREE */
1534 		uint8_t lf_pad[ZAP_LEAF_ARRAY_BYTES];
1535 		uint16_t lf_next;	/* next in free list, or CHAIN_END */
1536 	} l_free;
1537 } zap_leaf_chunk_t;
1538 
1539 typedef struct zap_leaf {
1540 	int l_bs;			/* block size shift */
1541 	zap_leaf_phys_t *l_phys;
1542 } zap_leaf_t;
1543 
1544 /*
1545  * Define special zfs pflags
1546  */
1547 #define	ZFS_XATTR	0x1		/* is an extended attribute */
1548 #define	ZFS_INHERIT_ACE	0x2		/* ace has inheritable ACEs */
1549 #define	ZFS_ACL_TRIVIAL 0x4		/* files ACL is trivial */
1550 
1551 #define	MASTER_NODE_OBJ	1
1552 
1553 /*
1554  * special attributes for master node.
1555  */
1556 
1557 #define	ZFS_FSID		"FSID"
1558 #define	ZFS_UNLINKED_SET	"DELETE_QUEUE"
1559 #define	ZFS_ROOT_OBJ		"ROOT"
1560 #define	ZPL_VERSION_OBJ		"VERSION"
1561 #define	ZFS_PROP_BLOCKPERPAGE	"BLOCKPERPAGE"
1562 #define	ZFS_PROP_NOGROWBLOCKS	"NOGROWBLOCKS"
1563 
1564 #define	ZFS_FLAG_BLOCKPERPAGE	0x1
1565 #define	ZFS_FLAG_NOGROWBLOCKS	0x2
1566 
1567 /*
1568  * ZPL version - rev'd whenever an incompatible on-disk format change
1569  * occurs.  Independent of SPA/DMU/ZAP versioning.
1570  */
1571 
1572 #define	ZPL_VERSION		1ULL
1573 
1574 /*
1575  * The directory entry has the type (currently unused on Solaris) in the
1576  * top 4 bits, and the object number in the low 48 bits.  The "middle"
1577  * 12 bits are unused.
1578  */
1579 #define	ZFS_DIRENT_TYPE(de) BF64_GET(de, 60, 4)
1580 #define	ZFS_DIRENT_OBJ(de) BF64_GET(de, 0, 48)
1581 #define	ZFS_DIRENT_MAKE(type, obj) (((uint64_t)type << 60) | obj)
1582 
1583 typedef struct ace {
1584 	uid_t		a_who;		/* uid or gid */
1585 	uint32_t	a_access_mask;	/* read,write,... */
1586 	uint16_t	a_flags;	/* see below */
1587 	uint16_t	a_type;		/* allow or deny */
1588 } ace_t;
1589 
1590 #define ACE_SLOT_CNT	6
1591 
1592 typedef struct zfs_znode_acl {
1593 	uint64_t	z_acl_extern_obj;	  /* ext acl pieces */
1594 	uint32_t	z_acl_count;		  /* Number of ACEs */
1595 	uint16_t	z_acl_version;		  /* acl version */
1596 	uint16_t	z_acl_pad;		  /* pad */
1597 	ace_t		z_ace_data[ACE_SLOT_CNT]; /* 6 standard ACEs */
1598 } zfs_znode_acl_t;
1599 
1600 /*
1601  * This is the persistent portion of the znode.  It is stored
1602  * in the "bonus buffer" of the file.  Short symbolic links
1603  * are also stored in the bonus buffer.
1604  */
1605 typedef struct znode_phys {
1606 	uint64_t zp_atime[2];		/*  0 - last file access time */
1607 	uint64_t zp_mtime[2];		/* 16 - last file modification time */
1608 	uint64_t zp_ctime[2];		/* 32 - last file change time */
1609 	uint64_t zp_crtime[2];		/* 48 - creation time */
1610 	uint64_t zp_gen;		/* 64 - generation (txg of creation) */
1611 	uint64_t zp_mode;		/* 72 - file mode bits */
1612 	uint64_t zp_size;		/* 80 - size of file */
1613 	uint64_t zp_parent;		/* 88 - directory parent (`..') */
1614 	uint64_t zp_links;		/* 96 - number of links to file */
1615 	uint64_t zp_xattr;		/* 104 - DMU object for xattrs */
1616 	uint64_t zp_rdev;		/* 112 - dev_t for VBLK & VCHR files */
1617 	uint64_t zp_flags;		/* 120 - persistent flags */
1618 	uint64_t zp_uid;		/* 128 - file owner */
1619 	uint64_t zp_gid;		/* 136 - owning group */
1620 	uint64_t zp_pad[4];		/* 144 - future */
1621 	zfs_znode_acl_t zp_acl;		/* 176 - 263 ACL */
1622 	/*
1623 	 * Data may pad out any remaining bytes in the znode buffer, eg:
1624 	 *
1625 	 * |<---------------------- dnode_phys (512) ------------------------>|
1626 	 * |<-- dnode (192) --->|<----------- "bonus" buffer (320) ---------->|
1627 	 *			|<---- znode (264) ---->|<---- data (56) ---->|
1628 	 *
1629 	 * At present, we only use this space to store symbolic links.
1630 	 */
1631 } znode_phys_t;
1632 
1633 /*
1634  * In-core vdev representation.
1635  */
1636 struct vdev;
1637 struct spa;
1638 typedef int vdev_phys_read_t(struct vdev *vdev, void *priv,
1639     off_t offset, void *buf, size_t bytes);
1640 typedef int vdev_read_t(struct vdev *vdev, const blkptr_t *bp,
1641     void *buf, off_t offset, size_t bytes);
1642 
1643 typedef STAILQ_HEAD(vdev_list, vdev) vdev_list_t;
1644 
1645 typedef struct vdev_indirect_mapping_entry_phys {
1646 	/*
1647 	 * Decode with DVA_MAPPING_* macros.
1648 	 * Contains:
1649 	 *   the source offset (low 63 bits)
1650 	 *   the one-bit "mark", used for garbage collection (by zdb)
1651 	 */
1652 	uint64_t vimep_src;
1653 
1654 	/*
1655 	 * Note: the DVA's asize is 24 bits, and can thus store ranges
1656 	 * up to 8GB.
1657 	 */
1658 	dva_t	vimep_dst;
1659 } vdev_indirect_mapping_entry_phys_t;
1660 
1661 #define	DVA_MAPPING_GET_SRC_OFFSET(vimep)	\
1662 	BF64_GET_SB((vimep)->vimep_src, 0, 63, SPA_MINBLOCKSHIFT, 0)
1663 #define	DVA_MAPPING_SET_SRC_OFFSET(vimep, x)	\
1664 	BF64_SET_SB((vimep)->vimep_src, 0, 63, SPA_MINBLOCKSHIFT, 0, x)
1665 
1666 typedef struct vdev_indirect_mapping_entry {
1667 	vdev_indirect_mapping_entry_phys_t	vime_mapping;
1668 	uint32_t				vime_obsolete_count;
1669 	list_node_t				vime_node;
1670 } vdev_indirect_mapping_entry_t;
1671 
1672 /*
1673  * This is stored in the bonus buffer of the mapping object, see comment of
1674  * vdev_indirect_config for more details.
1675  */
1676 typedef struct vdev_indirect_mapping_phys {
1677 	uint64_t	vimp_max_offset;
1678 	uint64_t	vimp_bytes_mapped;
1679 	uint64_t	vimp_num_entries; /* number of v_i_m_entry_phys_t's */
1680 
1681 	/*
1682 	 * For each entry in the mapping object, this object contains an
1683 	 * entry representing the number of bytes of that mapping entry
1684 	 * that were no longer in use by the pool at the time this indirect
1685 	 * vdev was last condensed.
1686 	 */
1687 	uint64_t	vimp_counts_object;
1688 } vdev_indirect_mapping_phys_t;
1689 
1690 #define	VDEV_INDIRECT_MAPPING_SIZE_V0	(3 * sizeof (uint64_t))
1691 
1692 typedef struct vdev_indirect_mapping {
1693 	uint64_t	vim_object;
1694 	boolean_t	vim_havecounts;
1695 
1696 	/* vim_entries segment offset currently in memory. */
1697 	uint64_t	vim_entry_offset;
1698 	/* vim_entries segment size. */
1699 	size_t		vim_num_entries;
1700 
1701 	/* Needed by dnode_read() */
1702 	const void	*vim_spa;
1703 	dnode_phys_t	*vim_dn;
1704 
1705 	/*
1706 	 * An ordered array of mapping entries, sorted by source offset.
1707 	 * Note that vim_entries is needed during a removal (and contains
1708 	 * mappings that have been synced to disk so far) to handle frees
1709 	 * from the removing device.
1710 	 */
1711 	vdev_indirect_mapping_entry_phys_t *vim_entries;
1712 	objset_phys_t	*vim_objset;
1713 	vdev_indirect_mapping_phys_t	*vim_phys;
1714 } vdev_indirect_mapping_t;
1715 
1716 /*
1717  * On-disk indirect vdev state.
1718  *
1719  * An indirect vdev is described exclusively in the MOS config of a pool.
1720  * The config for an indirect vdev includes several fields, which are
1721  * accessed in memory by a vdev_indirect_config_t.
1722  */
1723 typedef struct vdev_indirect_config {
1724 	/*
1725 	 * Object (in MOS) which contains the indirect mapping. This object
1726 	 * contains an array of vdev_indirect_mapping_entry_phys_t ordered by
1727 	 * vimep_src. The bonus buffer for this object is a
1728 	 * vdev_indirect_mapping_phys_t. This object is allocated when a vdev
1729 	 * removal is initiated.
1730 	 *
1731 	 * Note that this object can be empty if none of the data on the vdev
1732 	 * has been copied yet.
1733 	 */
1734 	uint64_t	vic_mapping_object;
1735 
1736 	/*
1737 	 * Object (in MOS) which contains the birth times for the mapping
1738 	 * entries. This object contains an array of
1739 	 * vdev_indirect_birth_entry_phys_t sorted by vibe_offset. The bonus
1740 	 * buffer for this object is a vdev_indirect_birth_phys_t. This object
1741 	 * is allocated when a vdev removal is initiated.
1742 	 *
1743 	 * Note that this object can be empty if none of the vdev has yet been
1744 	 * copied.
1745 	 */
1746 	uint64_t	vic_births_object;
1747 
1748 /*
1749  * This is the vdev ID which was removed previous to this vdev, or
1750  * UINT64_MAX if there are no previously removed vdevs.
1751  */
1752 	uint64_t	vic_prev_indirect_vdev;
1753 } vdev_indirect_config_t;
1754 
1755 typedef struct vdev {
1756 	STAILQ_ENTRY(vdev) v_childlink;	/* link in parent's child list */
1757 	STAILQ_ENTRY(vdev) v_alllink;	/* link in global vdev list */
1758 	vdev_list_t	v_children;	/* children of this vdev */
1759 	const char	*v_name;	/* vdev name */
1760 	uint64_t	v_guid;		/* vdev guid */
1761 	uint64_t	v_id;		/* index in parent */
1762 	uint64_t	v_psize;	/* physical device capacity */
1763 	int		v_ashift;	/* offset to block shift */
1764 	int		v_nparity;	/* # parity for raidz */
1765 	struct vdev	*v_top;		/* parent vdev */
1766 	size_t		v_nchildren;	/* # children */
1767 	vdev_state_t	v_state;	/* current state */
1768 	vdev_phys_read_t *v_phys_read;	/* read from raw leaf vdev */
1769 	vdev_read_t	*v_read;	/* read from vdev */
1770 	void		*v_read_priv;	/* private data for read function */
1771 	boolean_t	v_islog;
1772 	struct spa	*v_spa;		/* link to spa */
1773 	/*
1774 	 * Values stored in the config for an indirect or removing vdev.
1775 	 */
1776 	vdev_indirect_config_t vdev_indirect_config;
1777 	vdev_indirect_mapping_t *v_mapping;
1778 } vdev_t;
1779 
1780 /*
1781  * In-core pool representation.
1782  */
1783 typedef STAILQ_HEAD(spa_list, spa) spa_list_t;
1784 
1785 typedef struct spa {
1786 	STAILQ_ENTRY(spa) spa_link;	/* link in global pool list */
1787 	char		*spa_name;	/* pool name */
1788 	uint64_t	spa_guid;	/* pool guid */
1789 	uint64_t	spa_txg;	/* most recent transaction */
1790 	struct uberblock spa_uberblock;	/* best uberblock so far */
1791 	vdev_t		*spa_root_vdev;	/* toplevel vdev container */
1792 	objset_phys_t	spa_mos;	/* MOS for this pool */
1793 	zio_cksum_salt_t spa_cksum_salt;	/* secret salt for cksum */
1794 	void		*spa_cksum_tmpls[ZIO_CHECKSUM_FUNCTIONS];
1795 	boolean_t	spa_with_log;	/* this pool has log */
1796 } spa_t;
1797 
1798 /* IO related arguments. */
1799 typedef struct zio {
1800 	spa_t		*io_spa;
1801 	blkptr_t	*io_bp;
1802 	void		*io_data;
1803 	uint64_t	io_size;
1804 	uint64_t	io_offset;
1805 
1806 	/* Stuff for the vdev stack */
1807 	vdev_t		*io_vd;
1808 	void		*io_vsd;
1809 
1810 	int		io_error;
1811 } zio_t;
1812 
1813 static void decode_embedded_bp_compressed(const blkptr_t *, void *);
1814