xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/spa.h (revision c3d26abc9ee97b4f60233556aadeb57e0bd30bb9)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
24  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
25  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
26  * Copyright 2013 Saso Kiselkov. All rights reserved.
27  * Copyright (c) 2014 Integros [integros.com]
28  */
29 
30 #ifndef _SYS_SPA_H
31 #define	_SYS_SPA_H
32 
33 #include <sys/avl.h>
34 #include <sys/zfs_context.h>
35 #include <sys/nvpair.h>
36 #include <sys/sysmacros.h>
37 #include <sys/types.h>
38 #include <sys/fs/zfs.h>
39 
40 #ifdef	__cplusplus
41 extern "C" {
42 #endif
43 
44 /*
45  * Forward references that lots of things need.
46  */
47 typedef struct spa spa_t;
48 typedef struct vdev vdev_t;
49 typedef struct metaslab metaslab_t;
50 typedef struct metaslab_group metaslab_group_t;
51 typedef struct metaslab_class metaslab_class_t;
52 typedef struct zio zio_t;
53 typedef struct zilog zilog_t;
54 typedef struct spa_aux_vdev spa_aux_vdev_t;
55 typedef struct ddt ddt_t;
56 typedef struct ddt_entry ddt_entry_t;
57 struct dsl_pool;
58 struct dsl_dataset;
59 
60 /*
61  * General-purpose 32-bit and 64-bit bitfield encodings.
62  */
63 #define	BF32_DECODE(x, low, len)	P2PHASE((x) >> (low), 1U << (len))
64 #define	BF64_DECODE(x, low, len)	P2PHASE((x) >> (low), 1ULL << (len))
65 #define	BF32_ENCODE(x, low, len)	(P2PHASE((x), 1U << (len)) << (low))
66 #define	BF64_ENCODE(x, low, len)	(P2PHASE((x), 1ULL << (len)) << (low))
67 
68 #define	BF32_GET(x, low, len)		BF32_DECODE(x, low, len)
69 #define	BF64_GET(x, low, len)		BF64_DECODE(x, low, len)
70 
71 #define	BF32_SET(x, low, len, val) do { \
72 	ASSERT3U(val, <, 1U << (len)); \
73 	ASSERT3U(low + len, <=, 32); \
74 	(x) ^= BF32_ENCODE((x >> low) ^ (val), low, len); \
75 _NOTE(CONSTCOND) } while (0)
76 
77 #define	BF64_SET(x, low, len, val) do { \
78 	ASSERT3U(val, <, 1ULL << (len)); \
79 	ASSERT3U(low + len, <=, 64); \
80 	((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len)); \
81 _NOTE(CONSTCOND) } while (0)
82 
83 #define	BF32_GET_SB(x, low, len, shift, bias)	\
84 	((BF32_GET(x, low, len) + (bias)) << (shift))
85 #define	BF64_GET_SB(x, low, len, shift, bias)	\
86 	((BF64_GET(x, low, len) + (bias)) << (shift))
87 
88 #define	BF32_SET_SB(x, low, len, shift, bias, val) do { \
89 	ASSERT(IS_P2ALIGNED(val, 1U << shift)); \
90 	ASSERT3S((val) >> (shift), >=, bias); \
91 	BF32_SET(x, low, len, ((val) >> (shift)) - (bias)); \
92 _NOTE(CONSTCOND) } while (0)
93 #define	BF64_SET_SB(x, low, len, shift, bias, val) do { \
94 	ASSERT(IS_P2ALIGNED(val, 1ULL << shift)); \
95 	ASSERT3S((val) >> (shift), >=, bias); \
96 	BF64_SET(x, low, len, ((val) >> (shift)) - (bias)); \
97 _NOTE(CONSTCOND) } while (0)
98 
99 /*
100  * We currently support block sizes from 512 bytes to 16MB.
101  * The benefits of larger blocks, and thus larger IO, need to be weighed
102  * against the cost of COWing a giant block to modify one byte, and the
103  * large latency of reading or writing a large block.
104  *
105  * Note that although blocks up to 16MB are supported, the recordsize
106  * property can not be set larger than zfs_max_recordsize (default 1MB).
107  * See the comment near zfs_max_recordsize in dsl_dataset.c for details.
108  *
109  * Note that although the LSIZE field of the blkptr_t can store sizes up
110  * to 32MB, the dnode's dn_datablkszsec can only store sizes up to
111  * 32MB - 512 bytes.  Therefore, we limit SPA_MAXBLOCKSIZE to 16MB.
112  */
113 #define	SPA_MINBLOCKSHIFT	9
114 #define	SPA_OLD_MAXBLOCKSHIFT	17
115 #define	SPA_MAXBLOCKSHIFT	24
116 #define	SPA_MINBLOCKSIZE	(1ULL << SPA_MINBLOCKSHIFT)
117 #define	SPA_OLD_MAXBLOCKSIZE	(1ULL << SPA_OLD_MAXBLOCKSHIFT)
118 #define	SPA_MAXBLOCKSIZE	(1ULL << SPA_MAXBLOCKSHIFT)
119 
120 /*
121  * Size of block to hold the configuration data (a packed nvlist)
122  */
123 #define	SPA_CONFIG_BLOCKSIZE	(1ULL << 14)
124 
125 /*
126  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
127  * The ASIZE encoding should be at least 64 times larger (6 more bits)
128  * to support up to 4-way RAID-Z mirror mode with worst-case gang block
129  * overhead, three DVAs per bp, plus one more bit in case we do anything
130  * else that expands the ASIZE.
131  */
132 #define	SPA_LSIZEBITS		16	/* LSIZE up to 32M (2^16 * 512)	*/
133 #define	SPA_PSIZEBITS		16	/* PSIZE up to 32M (2^16 * 512)	*/
134 #define	SPA_ASIZEBITS		24	/* ASIZE up to 64 times larger	*/
135 
136 /*
137  * All SPA data is represented by 128-bit data virtual addresses (DVAs).
138  * The members of the dva_t should be considered opaque outside the SPA.
139  */
140 typedef struct dva {
141 	uint64_t	dva_word[2];
142 } dva_t;
143 
144 /*
145  * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
146  */
147 typedef struct zio_cksum {
148 	uint64_t	zc_word[4];
149 } zio_cksum_t;
150 
151 /*
152  * Some checksums/hashes need a 256-bit initialization salt. This salt is kept
153  * secret and is suitable for use in MAC algorithms as the key.
154  */
155 typedef struct zio_cksum_salt {
156 	uint8_t		zcs_bytes[32];
157 } zio_cksum_salt_t;
158 
159 /*
160  * Each block is described by its DVAs, time of birth, checksum, etc.
161  * The word-by-word, bit-by-bit layout of the blkptr is as follows:
162  *
163  *	64	56	48	40	32	24	16	8	0
164  *	+-------+-------+-------+-------+-------+-------+-------+-------+
165  * 0	|		vdev1		| GRID  |	  ASIZE		|
166  *	+-------+-------+-------+-------+-------+-------+-------+-------+
167  * 1	|G|			 offset1				|
168  *	+-------+-------+-------+-------+-------+-------+-------+-------+
169  * 2	|		vdev2		| GRID  |	  ASIZE		|
170  *	+-------+-------+-------+-------+-------+-------+-------+-------+
171  * 3	|G|			 offset2				|
172  *	+-------+-------+-------+-------+-------+-------+-------+-------+
173  * 4	|		vdev3		| GRID  |	  ASIZE		|
174  *	+-------+-------+-------+-------+-------+-------+-------+-------+
175  * 5	|G|			 offset3				|
176  *	+-------+-------+-------+-------+-------+-------+-------+-------+
177  * 6	|BDX|lvl| type	| cksum |E| comp|    PSIZE	|     LSIZE	|
178  *	+-------+-------+-------+-------+-------+-------+-------+-------+
179  * 7	|			padding					|
180  *	+-------+-------+-------+-------+-------+-------+-------+-------+
181  * 8	|			padding					|
182  *	+-------+-------+-------+-------+-------+-------+-------+-------+
183  * 9	|			physical birth txg			|
184  *	+-------+-------+-------+-------+-------+-------+-------+-------+
185  * a	|			logical birth txg			|
186  *	+-------+-------+-------+-------+-------+-------+-------+-------+
187  * b	|			fill count				|
188  *	+-------+-------+-------+-------+-------+-------+-------+-------+
189  * c	|			checksum[0]				|
190  *	+-------+-------+-------+-------+-------+-------+-------+-------+
191  * d	|			checksum[1]				|
192  *	+-------+-------+-------+-------+-------+-------+-------+-------+
193  * e	|			checksum[2]				|
194  *	+-------+-------+-------+-------+-------+-------+-------+-------+
195  * f	|			checksum[3]				|
196  *	+-------+-------+-------+-------+-------+-------+-------+-------+
197  *
198  * Legend:
199  *
200  * vdev		virtual device ID
201  * offset	offset into virtual device
202  * LSIZE	logical size
203  * PSIZE	physical size (after compression)
204  * ASIZE	allocated size (including RAID-Z parity and gang block headers)
205  * GRID		RAID-Z layout information (reserved for future use)
206  * cksum	checksum function
207  * comp		compression function
208  * G		gang block indicator
209  * B		byteorder (endianness)
210  * D		dedup
211  * X		encryption (on version 30, which is not supported)
212  * E		blkptr_t contains embedded data (see below)
213  * lvl		level of indirection
214  * type		DMU object type
215  * phys birth	txg of block allocation; zero if same as logical birth txg
216  * log. birth	transaction group in which the block was logically born
217  * fill count	number of non-zero blocks under this bp
218  * checksum[4]	256-bit checksum of the data this bp describes
219  */
220 
221 /*
222  * "Embedded" blkptr_t's don't actually point to a block, instead they
223  * have a data payload embedded in the blkptr_t itself.  See the comment
224  * in blkptr.c for more details.
225  *
226  * The blkptr_t is laid out as follows:
227  *
228  *	64	56	48	40	32	24	16	8	0
229  *	+-------+-------+-------+-------+-------+-------+-------+-------+
230  * 0	|      payload                                                  |
231  * 1	|      payload                                                  |
232  * 2	|      payload                                                  |
233  * 3	|      payload                                                  |
234  * 4	|      payload                                                  |
235  * 5	|      payload                                                  |
236  *	+-------+-------+-------+-------+-------+-------+-------+-------+
237  * 6	|BDX|lvl| type	| etype |E| comp| PSIZE|              LSIZE	|
238  *	+-------+-------+-------+-------+-------+-------+-------+-------+
239  * 7	|      payload                                                  |
240  * 8	|      payload                                                  |
241  * 9	|      payload                                                  |
242  *	+-------+-------+-------+-------+-------+-------+-------+-------+
243  * a	|			logical birth txg			|
244  *	+-------+-------+-------+-------+-------+-------+-------+-------+
245  * b	|      payload                                                  |
246  * c	|      payload                                                  |
247  * d	|      payload                                                  |
248  * e	|      payload                                                  |
249  * f	|      payload                                                  |
250  *	+-------+-------+-------+-------+-------+-------+-------+-------+
251  *
252  * Legend:
253  *
254  * payload		contains the embedded data
255  * B (byteorder)	byteorder (endianness)
256  * D (dedup)		padding (set to zero)
257  * X			encryption (set to zero; see above)
258  * E (embedded)		set to one
259  * lvl			indirection level
260  * type			DMU object type
261  * etype		how to interpret embedded data (BP_EMBEDDED_TYPE_*)
262  * comp			compression function of payload
263  * PSIZE		size of payload after compression, in bytes
264  * LSIZE		logical size of payload, in bytes
265  *			note that 25 bits is enough to store the largest
266  *			"normal" BP's LSIZE (2^16 * 2^9) in bytes
267  * log. birth		transaction group in which the block was logically born
268  *
269  * Note that LSIZE and PSIZE are stored in bytes, whereas for non-embedded
270  * bp's they are stored in units of SPA_MINBLOCKSHIFT.
271  * Generally, the generic BP_GET_*() macros can be used on embedded BP's.
272  * The B, D, X, lvl, type, and comp fields are stored the same as with normal
273  * BP's so the BP_SET_* macros can be used with them.  etype, PSIZE, LSIZE must
274  * be set with the BPE_SET_* macros.  BP_SET_EMBEDDED() should be called before
275  * other macros, as they assert that they are only used on BP's of the correct
276  * "embedded-ness".
277  */
278 
279 #define	BPE_GET_ETYPE(bp)	\
280 	(ASSERT(BP_IS_EMBEDDED(bp)), \
281 	BF64_GET((bp)->blk_prop, 40, 8))
282 #define	BPE_SET_ETYPE(bp, t)	do { \
283 	ASSERT(BP_IS_EMBEDDED(bp)); \
284 	BF64_SET((bp)->blk_prop, 40, 8, t); \
285 _NOTE(CONSTCOND) } while (0)
286 
287 #define	BPE_GET_LSIZE(bp)	\
288 	(ASSERT(BP_IS_EMBEDDED(bp)), \
289 	BF64_GET_SB((bp)->blk_prop, 0, 25, 0, 1))
290 #define	BPE_SET_LSIZE(bp, x)	do { \
291 	ASSERT(BP_IS_EMBEDDED(bp)); \
292 	BF64_SET_SB((bp)->blk_prop, 0, 25, 0, 1, x); \
293 _NOTE(CONSTCOND) } while (0)
294 
295 #define	BPE_GET_PSIZE(bp)	\
296 	(ASSERT(BP_IS_EMBEDDED(bp)), \
297 	BF64_GET_SB((bp)->blk_prop, 25, 7, 0, 1))
298 #define	BPE_SET_PSIZE(bp, x)	do { \
299 	ASSERT(BP_IS_EMBEDDED(bp)); \
300 	BF64_SET_SB((bp)->blk_prop, 25, 7, 0, 1, x); \
301 _NOTE(CONSTCOND) } while (0)
302 
303 typedef enum bp_embedded_type {
304 	BP_EMBEDDED_TYPE_DATA,
305 	BP_EMBEDDED_TYPE_RESERVED, /* Reserved for an unintegrated feature. */
306 	NUM_BP_EMBEDDED_TYPES = BP_EMBEDDED_TYPE_RESERVED
307 } bp_embedded_type_t;
308 
309 #define	BPE_NUM_WORDS 14
310 #define	BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
311 #define	BPE_IS_PAYLOADWORD(bp, wp) \
312 	((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
313 
314 #define	SPA_BLKPTRSHIFT	7		/* blkptr_t is 128 bytes	*/
315 #define	SPA_DVAS_PER_BP	3		/* Number of DVAs in a bp	*/
316 
317 /*
318  * A block is a hole when it has either 1) never been written to, or
319  * 2) is zero-filled. In both cases, ZFS can return all zeroes for all reads
320  * without physically allocating disk space. Holes are represented in the
321  * blkptr_t structure by zeroed blk_dva. Correct checking for holes is
322  * done through the BP_IS_HOLE macro. For holes, the logical size, level,
323  * DMU object type, and birth times are all also stored for holes that
324  * were written to at some point (i.e. were punched after having been filled).
325  */
326 typedef struct blkptr {
327 	dva_t		blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
328 	uint64_t	blk_prop;	/* size, compression, type, etc	    */
329 	uint64_t	blk_pad[2];	/* Extra space for the future	    */
330 	uint64_t	blk_phys_birth;	/* txg when block was allocated	    */
331 	uint64_t	blk_birth;	/* transaction group at birth	    */
332 	uint64_t	blk_fill;	/* fill count			    */
333 	zio_cksum_t	blk_cksum;	/* 256-bit checksum		    */
334 } blkptr_t;
335 
336 /*
337  * Macros to get and set fields in a bp or DVA.
338  */
339 #define	DVA_GET_ASIZE(dva)	\
340 	BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0)
341 #define	DVA_SET_ASIZE(dva, x)	\
342 	BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \
343 	SPA_MINBLOCKSHIFT, 0, x)
344 
345 #define	DVA_GET_GRID(dva)	BF64_GET((dva)->dva_word[0], 24, 8)
346 #define	DVA_SET_GRID(dva, x)	BF64_SET((dva)->dva_word[0], 24, 8, x)
347 
348 #define	DVA_GET_VDEV(dva)	BF64_GET((dva)->dva_word[0], 32, 32)
349 #define	DVA_SET_VDEV(dva, x)	BF64_SET((dva)->dva_word[0], 32, 32, x)
350 
351 #define	DVA_GET_OFFSET(dva)	\
352 	BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
353 #define	DVA_SET_OFFSET(dva, x)	\
354 	BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
355 
356 #define	DVA_GET_GANG(dva)	BF64_GET((dva)->dva_word[1], 63, 1)
357 #define	DVA_SET_GANG(dva, x)	BF64_SET((dva)->dva_word[1], 63, 1, x)
358 
359 #define	BP_GET_LSIZE(bp)	\
360 	(BP_IS_EMBEDDED(bp) ?	\
361 	(BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA ? BPE_GET_LSIZE(bp) : 0): \
362 	BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1))
363 #define	BP_SET_LSIZE(bp, x)	do { \
364 	ASSERT(!BP_IS_EMBEDDED(bp)); \
365 	BF64_SET_SB((bp)->blk_prop, \
366 	    0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x); \
367 _NOTE(CONSTCOND) } while (0)
368 
369 #define	BP_GET_PSIZE(bp)	\
370 	(BP_IS_EMBEDDED(bp) ? 0 : \
371 	BF64_GET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1))
372 #define	BP_SET_PSIZE(bp, x)	do { \
373 	ASSERT(!BP_IS_EMBEDDED(bp)); \
374 	BF64_SET_SB((bp)->blk_prop, \
375 	    16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x); \
376 _NOTE(CONSTCOND) } while (0)
377 
378 #define	BP_GET_COMPRESS(bp)		BF64_GET((bp)->blk_prop, 32, 7)
379 #define	BP_SET_COMPRESS(bp, x)		BF64_SET((bp)->blk_prop, 32, 7, x)
380 
381 #define	BP_IS_EMBEDDED(bp)		BF64_GET((bp)->blk_prop, 39, 1)
382 #define	BP_SET_EMBEDDED(bp, x)		BF64_SET((bp)->blk_prop, 39, 1, x)
383 
384 #define	BP_GET_CHECKSUM(bp)		\
385 	(BP_IS_EMBEDDED(bp) ? ZIO_CHECKSUM_OFF : \
386 	BF64_GET((bp)->blk_prop, 40, 8))
387 #define	BP_SET_CHECKSUM(bp, x)		do { \
388 	ASSERT(!BP_IS_EMBEDDED(bp)); \
389 	BF64_SET((bp)->blk_prop, 40, 8, x); \
390 _NOTE(CONSTCOND) } while (0)
391 
392 #define	BP_GET_TYPE(bp)			BF64_GET((bp)->blk_prop, 48, 8)
393 #define	BP_SET_TYPE(bp, x)		BF64_SET((bp)->blk_prop, 48, 8, x)
394 
395 #define	BP_GET_LEVEL(bp)		BF64_GET((bp)->blk_prop, 56, 5)
396 #define	BP_SET_LEVEL(bp, x)		BF64_SET((bp)->blk_prop, 56, 5, x)
397 
398 #define	BP_GET_DEDUP(bp)		BF64_GET((bp)->blk_prop, 62, 1)
399 #define	BP_SET_DEDUP(bp, x)		BF64_SET((bp)->blk_prop, 62, 1, x)
400 
401 #define	BP_GET_BYTEORDER(bp)		BF64_GET((bp)->blk_prop, 63, 1)
402 #define	BP_SET_BYTEORDER(bp, x)		BF64_SET((bp)->blk_prop, 63, 1, x)
403 
404 #define	BP_PHYSICAL_BIRTH(bp)		\
405 	(BP_IS_EMBEDDED(bp) ? 0 : \
406 	(bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
407 
408 #define	BP_SET_BIRTH(bp, logical, physical)	\
409 {						\
410 	ASSERT(!BP_IS_EMBEDDED(bp));		\
411 	(bp)->blk_birth = (logical);		\
412 	(bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \
413 }
414 
415 #define	BP_GET_FILL(bp) (BP_IS_EMBEDDED(bp) ? 1 : (bp)->blk_fill)
416 
417 #define	BP_GET_ASIZE(bp)	\
418 	(BP_IS_EMBEDDED(bp) ? 0 : \
419 	DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
420 	DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
421 	DVA_GET_ASIZE(&(bp)->blk_dva[2]))
422 
423 #define	BP_GET_UCSIZE(bp) \
424 	((BP_GET_LEVEL(bp) > 0 || DMU_OT_IS_METADATA(BP_GET_TYPE(bp))) ? \
425 	BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp))
426 
427 #define	BP_GET_NDVAS(bp)	\
428 	(BP_IS_EMBEDDED(bp) ? 0 : \
429 	!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
430 	!!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
431 	!!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
432 
433 #define	BP_COUNT_GANG(bp)	\
434 	(BP_IS_EMBEDDED(bp) ? 0 : \
435 	(DVA_GET_GANG(&(bp)->blk_dva[0]) + \
436 	DVA_GET_GANG(&(bp)->blk_dva[1]) + \
437 	DVA_GET_GANG(&(bp)->blk_dva[2])))
438 
439 #define	DVA_EQUAL(dva1, dva2)	\
440 	((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
441 	(dva1)->dva_word[0] == (dva2)->dva_word[0])
442 
443 #define	BP_EQUAL(bp1, bp2)	\
444 	(BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) &&	\
445 	(bp1)->blk_birth == (bp2)->blk_birth &&			\
446 	DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) &&	\
447 	DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) &&	\
448 	DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2]))
449 
450 #define	ZIO_CHECKSUM_EQUAL(zc1, zc2) \
451 	(0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
452 	((zc1).zc_word[1] - (zc2).zc_word[1]) | \
453 	((zc1).zc_word[2] - (zc2).zc_word[2]) | \
454 	((zc1).zc_word[3] - (zc2).zc_word[3])))
455 
456 #define	ZIO_CHECKSUM_IS_ZERO(zc) \
457 	(0 == ((zc)->zc_word[0] | (zc)->zc_word[1] | \
458 	(zc)->zc_word[2] | (zc)->zc_word[3]))
459 
460 #define	ZIO_CHECKSUM_BSWAP(zcp)					\
461 {								\
462 	(zcp)->zc_word[0] = BSWAP_64((zcp)->zc_word[0]);	\
463 	(zcp)->zc_word[1] = BSWAP_64((zcp)->zc_word[1]);	\
464 	(zcp)->zc_word[2] = BSWAP_64((zcp)->zc_word[2]);	\
465 	(zcp)->zc_word[3] = BSWAP_64((zcp)->zc_word[3]);	\
466 }
467 
468 
469 #define	DVA_IS_VALID(dva)	(DVA_GET_ASIZE(dva) != 0)
470 
471 #define	ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)	\
472 {						\
473 	(zcp)->zc_word[0] = w0;			\
474 	(zcp)->zc_word[1] = w1;			\
475 	(zcp)->zc_word[2] = w2;			\
476 	(zcp)->zc_word[3] = w3;			\
477 }
478 
479 #define	BP_IDENTITY(bp)		(ASSERT(!BP_IS_EMBEDDED(bp)), &(bp)->blk_dva[0])
480 #define	BP_IS_GANG(bp)		\
481 	(BP_IS_EMBEDDED(bp) ? B_FALSE : DVA_GET_GANG(BP_IDENTITY(bp)))
482 #define	DVA_IS_EMPTY(dva)	((dva)->dva_word[0] == 0ULL &&	\
483 				(dva)->dva_word[1] == 0ULL)
484 #define	BP_IS_HOLE(bp) \
485 	(!BP_IS_EMBEDDED(bp) && DVA_IS_EMPTY(BP_IDENTITY(bp)))
486 
487 /* BP_IS_RAIDZ(bp) assumes no block compression */
488 #define	BP_IS_RAIDZ(bp)		(DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \
489 				BP_GET_PSIZE(bp))
490 
491 #define	BP_ZERO(bp)				\
492 {						\
493 	(bp)->blk_dva[0].dva_word[0] = 0;	\
494 	(bp)->blk_dva[0].dva_word[1] = 0;	\
495 	(bp)->blk_dva[1].dva_word[0] = 0;	\
496 	(bp)->blk_dva[1].dva_word[1] = 0;	\
497 	(bp)->blk_dva[2].dva_word[0] = 0;	\
498 	(bp)->blk_dva[2].dva_word[1] = 0;	\
499 	(bp)->blk_prop = 0;			\
500 	(bp)->blk_pad[0] = 0;			\
501 	(bp)->blk_pad[1] = 0;			\
502 	(bp)->blk_phys_birth = 0;		\
503 	(bp)->blk_birth = 0;			\
504 	(bp)->blk_fill = 0;			\
505 	ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0);	\
506 }
507 
508 #ifdef _BIG_ENDIAN
509 #define	ZFS_HOST_BYTEORDER	(0ULL)
510 #else
511 #define	ZFS_HOST_BYTEORDER	(1ULL)
512 #endif
513 
514 #define	BP_SHOULD_BYTESWAP(bp)	(BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)
515 
516 #define	BP_SPRINTF_LEN	320
517 
518 /*
519  * This macro allows code sharing between zfs, libzpool, and mdb.
520  * 'func' is either snprintf() or mdb_snprintf().
521  * 'ws' (whitespace) can be ' ' for single-line format, '\n' for multi-line.
522  */
523 #define	SNPRINTF_BLKPTR(func, ws, buf, size, bp, type, checksum, compress) \
524 {									\
525 	static const char *copyname[] =					\
526 	    { "zero", "single", "double", "triple" };			\
527 	int len = 0;							\
528 	int copies = 0;							\
529 									\
530 	if (bp == NULL) {						\
531 		len += func(buf + len, size - len, "<NULL>");		\
532 	} else if (BP_IS_HOLE(bp)) {					\
533 		len += func(buf + len, size - len,			\
534 		    "HOLE [L%llu %s] "					\
535 		    "size=%llxL birth=%lluL",				\
536 		    (u_longlong_t)BP_GET_LEVEL(bp),			\
537 		    type,						\
538 		    (u_longlong_t)BP_GET_LSIZE(bp),			\
539 		    (u_longlong_t)bp->blk_birth);			\
540 	} else if (BP_IS_EMBEDDED(bp)) {				\
541 		len = func(buf + len, size - len,			\
542 		    "EMBEDDED [L%llu %s] et=%u %s "			\
543 		    "size=%llxL/%llxP birth=%lluL",			\
544 		    (u_longlong_t)BP_GET_LEVEL(bp),			\
545 		    type,						\
546 		    (int)BPE_GET_ETYPE(bp),				\
547 		    compress,						\
548 		    (u_longlong_t)BPE_GET_LSIZE(bp),			\
549 		    (u_longlong_t)BPE_GET_PSIZE(bp),			\
550 		    (u_longlong_t)bp->blk_birth);			\
551 	} else {							\
552 		for (int d = 0; d < BP_GET_NDVAS(bp); d++) {		\
553 			const dva_t *dva = &bp->blk_dva[d];		\
554 			if (DVA_IS_VALID(dva))				\
555 				copies++;				\
556 			len += func(buf + len, size - len,		\
557 			    "DVA[%d]=<%llu:%llx:%llx>%c", d,		\
558 			    (u_longlong_t)DVA_GET_VDEV(dva),		\
559 			    (u_longlong_t)DVA_GET_OFFSET(dva),		\
560 			    (u_longlong_t)DVA_GET_ASIZE(dva),		\
561 			    ws);					\
562 		}							\
563 		if (BP_IS_GANG(bp) &&					\
564 		    DVA_GET_ASIZE(&bp->blk_dva[2]) <=			\
565 		    DVA_GET_ASIZE(&bp->blk_dva[1]) / 2)			\
566 			copies--;					\
567 		len += func(buf + len, size - len,			\
568 		    "[L%llu %s] %s %s %s %s %s %s%c"			\
569 		    "size=%llxL/%llxP birth=%lluL/%lluP fill=%llu%c"	\
570 		    "cksum=%llx:%llx:%llx:%llx",			\
571 		    (u_longlong_t)BP_GET_LEVEL(bp),			\
572 		    type,						\
573 		    checksum,						\
574 		    compress,						\
575 		    BP_GET_BYTEORDER(bp) == 0 ? "BE" : "LE",		\
576 		    BP_IS_GANG(bp) ? "gang" : "contiguous",		\
577 		    BP_GET_DEDUP(bp) ? "dedup" : "unique",		\
578 		    copyname[copies],					\
579 		    ws,							\
580 		    (u_longlong_t)BP_GET_LSIZE(bp),			\
581 		    (u_longlong_t)BP_GET_PSIZE(bp),			\
582 		    (u_longlong_t)bp->blk_birth,			\
583 		    (u_longlong_t)BP_PHYSICAL_BIRTH(bp),		\
584 		    (u_longlong_t)BP_GET_FILL(bp),			\
585 		    ws,							\
586 		    (u_longlong_t)bp->blk_cksum.zc_word[0],		\
587 		    (u_longlong_t)bp->blk_cksum.zc_word[1],		\
588 		    (u_longlong_t)bp->blk_cksum.zc_word[2],		\
589 		    (u_longlong_t)bp->blk_cksum.zc_word[3]);		\
590 	}								\
591 	ASSERT(len < size);						\
592 }
593 
594 #include <sys/dmu.h>
595 
596 #define	BP_GET_BUFC_TYPE(bp)						\
597 	(((BP_GET_LEVEL(bp) > 0) || (DMU_OT_IS_METADATA(BP_GET_TYPE(bp)))) ? \
598 	ARC_BUFC_METADATA : ARC_BUFC_DATA)
599 
600 typedef enum spa_import_type {
601 	SPA_IMPORT_EXISTING,
602 	SPA_IMPORT_ASSEMBLE
603 } spa_import_type_t;
604 
605 /* state manipulation functions */
606 extern int spa_open(const char *pool, spa_t **, void *tag);
607 extern int spa_open_rewind(const char *pool, spa_t **, void *tag,
608     nvlist_t *policy, nvlist_t **config);
609 extern int spa_get_stats(const char *pool, nvlist_t **config, char *altroot,
610     size_t buflen);
611 extern int spa_create(const char *pool, nvlist_t *config, nvlist_t *props,
612     nvlist_t *zplprops);
613 extern int spa_import_rootpool(char *devpath, char *devid);
614 extern int spa_import(const char *pool, nvlist_t *config, nvlist_t *props,
615     uint64_t flags);
616 extern nvlist_t *spa_tryimport(nvlist_t *tryconfig);
617 extern int spa_destroy(char *pool);
618 extern int spa_export(char *pool, nvlist_t **oldconfig, boolean_t force,
619     boolean_t hardforce);
620 extern int spa_reset(char *pool);
621 extern void spa_async_request(spa_t *spa, int flag);
622 extern void spa_async_unrequest(spa_t *spa, int flag);
623 extern void spa_async_suspend(spa_t *spa);
624 extern void spa_async_resume(spa_t *spa);
625 extern spa_t *spa_inject_addref(char *pool);
626 extern void spa_inject_delref(spa_t *spa);
627 extern void spa_scan_stat_init(spa_t *spa);
628 extern int spa_scan_get_stats(spa_t *spa, pool_scan_stat_t *ps);
629 
630 #define	SPA_ASYNC_CONFIG_UPDATE	0x01
631 #define	SPA_ASYNC_REMOVE	0x02
632 #define	SPA_ASYNC_PROBE		0x04
633 #define	SPA_ASYNC_RESILVER_DONE	0x08
634 #define	SPA_ASYNC_RESILVER	0x10
635 #define	SPA_ASYNC_AUTOEXPAND	0x20
636 #define	SPA_ASYNC_REMOVE_DONE	0x40
637 #define	SPA_ASYNC_REMOVE_STOP	0x80
638 
639 /*
640  * Controls the behavior of spa_vdev_remove().
641  */
642 #define	SPA_REMOVE_UNSPARE	0x01
643 #define	SPA_REMOVE_DONE		0x02
644 
645 /* device manipulation */
646 extern int spa_vdev_add(spa_t *spa, nvlist_t *nvroot);
647 extern int spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot,
648     int replacing);
649 extern int spa_vdev_detach(spa_t *spa, uint64_t guid, uint64_t pguid,
650     int replace_done);
651 extern int spa_vdev_remove(spa_t *spa, uint64_t guid, boolean_t unspare);
652 extern boolean_t spa_vdev_remove_active(spa_t *spa);
653 extern int spa_vdev_setpath(spa_t *spa, uint64_t guid, const char *newpath);
654 extern int spa_vdev_setfru(spa_t *spa, uint64_t guid, const char *newfru);
655 extern int spa_vdev_split_mirror(spa_t *spa, char *newname, nvlist_t *config,
656     nvlist_t *props, boolean_t exp);
657 
658 /* spare state (which is global across all pools) */
659 extern void spa_spare_add(vdev_t *vd);
660 extern void spa_spare_remove(vdev_t *vd);
661 extern boolean_t spa_spare_exists(uint64_t guid, uint64_t *pool, int *refcnt);
662 extern void spa_spare_activate(vdev_t *vd);
663 
664 /* L2ARC state (which is global across all pools) */
665 extern void spa_l2cache_add(vdev_t *vd);
666 extern void spa_l2cache_remove(vdev_t *vd);
667 extern boolean_t spa_l2cache_exists(uint64_t guid, uint64_t *pool);
668 extern void spa_l2cache_activate(vdev_t *vd);
669 extern void spa_l2cache_drop(spa_t *spa);
670 
671 /* scanning */
672 extern int spa_scan(spa_t *spa, pool_scan_func_t func);
673 extern int spa_scan_stop(spa_t *spa);
674 
675 /* spa syncing */
676 extern void spa_sync(spa_t *spa, uint64_t txg); /* only for DMU use */
677 extern void spa_sync_allpools(void);
678 
679 /* spa namespace global mutex */
680 extern kmutex_t spa_namespace_lock;
681 
682 /*
683  * SPA configuration functions in spa_config.c
684  */
685 
686 #define	SPA_CONFIG_UPDATE_POOL	0
687 #define	SPA_CONFIG_UPDATE_VDEVS	1
688 
689 extern void spa_config_sync(spa_t *, boolean_t, boolean_t);
690 extern void spa_config_load(void);
691 extern nvlist_t *spa_all_configs(uint64_t *);
692 extern void spa_config_set(spa_t *spa, nvlist_t *config);
693 extern nvlist_t *spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg,
694     int getstats);
695 extern void spa_config_update(spa_t *spa, int what);
696 
697 /*
698  * Miscellaneous SPA routines in spa_misc.c
699  */
700 
701 /* Namespace manipulation */
702 extern spa_t *spa_lookup(const char *name);
703 extern spa_t *spa_add(const char *name, nvlist_t *config, const char *altroot);
704 extern void spa_remove(spa_t *spa);
705 extern spa_t *spa_next(spa_t *prev);
706 
707 /* Refcount functions */
708 extern void spa_open_ref(spa_t *spa, void *tag);
709 extern void spa_close(spa_t *spa, void *tag);
710 extern void spa_async_close(spa_t *spa, void *tag);
711 extern boolean_t spa_refcount_zero(spa_t *spa);
712 
713 #define	SCL_NONE	0x00
714 #define	SCL_CONFIG	0x01
715 #define	SCL_STATE	0x02
716 #define	SCL_L2ARC	0x04		/* hack until L2ARC 2.0 */
717 #define	SCL_ALLOC	0x08
718 #define	SCL_ZIO		0x10
719 #define	SCL_FREE	0x20
720 #define	SCL_VDEV	0x40
721 #define	SCL_LOCKS	7
722 #define	SCL_ALL		((1 << SCL_LOCKS) - 1)
723 #define	SCL_STATE_ALL	(SCL_STATE | SCL_L2ARC | SCL_ZIO)
724 
725 /* Pool configuration locks */
726 extern int spa_config_tryenter(spa_t *spa, int locks, void *tag, krw_t rw);
727 extern void spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw);
728 extern void spa_config_exit(spa_t *spa, int locks, void *tag);
729 extern int spa_config_held(spa_t *spa, int locks, krw_t rw);
730 
731 /* Pool vdev add/remove lock */
732 extern uint64_t spa_vdev_enter(spa_t *spa);
733 extern uint64_t spa_vdev_config_enter(spa_t *spa);
734 extern void spa_vdev_config_exit(spa_t *spa, vdev_t *vd, uint64_t txg,
735     int error, char *tag);
736 extern int spa_vdev_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error);
737 
738 /* Pool vdev state change lock */
739 extern void spa_vdev_state_enter(spa_t *spa, int oplock);
740 extern int spa_vdev_state_exit(spa_t *spa, vdev_t *vd, int error);
741 
742 /* Log state */
743 typedef enum spa_log_state {
744 	SPA_LOG_UNKNOWN = 0,	/* unknown log state */
745 	SPA_LOG_MISSING,	/* missing log(s) */
746 	SPA_LOG_CLEAR,		/* clear the log(s) */
747 	SPA_LOG_GOOD,		/* log(s) are good */
748 } spa_log_state_t;
749 
750 extern spa_log_state_t spa_get_log_state(spa_t *spa);
751 extern void spa_set_log_state(spa_t *spa, spa_log_state_t state);
752 extern int spa_offline_log(spa_t *spa);
753 
754 /* Log claim callback */
755 extern void spa_claim_notify(zio_t *zio);
756 
757 /* Accessor functions */
758 extern boolean_t spa_shutting_down(spa_t *spa);
759 extern struct dsl_pool *spa_get_dsl(spa_t *spa);
760 extern boolean_t spa_is_initializing(spa_t *spa);
761 extern blkptr_t *spa_get_rootblkptr(spa_t *spa);
762 extern void spa_set_rootblkptr(spa_t *spa, const blkptr_t *bp);
763 extern void spa_altroot(spa_t *, char *, size_t);
764 extern int spa_sync_pass(spa_t *spa);
765 extern char *spa_name(spa_t *spa);
766 extern uint64_t spa_guid(spa_t *spa);
767 extern uint64_t spa_load_guid(spa_t *spa);
768 extern uint64_t spa_last_synced_txg(spa_t *spa);
769 extern uint64_t spa_first_txg(spa_t *spa);
770 extern uint64_t spa_syncing_txg(spa_t *spa);
771 extern uint64_t spa_version(spa_t *spa);
772 extern pool_state_t spa_state(spa_t *spa);
773 extern spa_load_state_t spa_load_state(spa_t *spa);
774 extern uint64_t spa_freeze_txg(spa_t *spa);
775 extern uint64_t spa_get_asize(spa_t *spa, uint64_t lsize);
776 extern uint64_t spa_get_dspace(spa_t *spa);
777 extern uint64_t spa_get_slop_space(spa_t *spa);
778 extern void spa_update_dspace(spa_t *spa);
779 extern uint64_t spa_version(spa_t *spa);
780 extern boolean_t spa_deflate(spa_t *spa);
781 extern metaslab_class_t *spa_normal_class(spa_t *spa);
782 extern metaslab_class_t *spa_log_class(spa_t *spa);
783 extern void spa_evicting_os_register(spa_t *, objset_t *os);
784 extern void spa_evicting_os_deregister(spa_t *, objset_t *os);
785 extern void spa_evicting_os_wait(spa_t *spa);
786 extern int spa_max_replication(spa_t *spa);
787 extern int spa_prev_software_version(spa_t *spa);
788 extern int spa_busy(void);
789 extern uint8_t spa_get_failmode(spa_t *spa);
790 extern boolean_t spa_suspended(spa_t *spa);
791 extern uint64_t spa_bootfs(spa_t *spa);
792 extern uint64_t spa_delegation(spa_t *spa);
793 extern objset_t *spa_meta_objset(spa_t *spa);
794 extern uint64_t spa_deadman_synctime(spa_t *spa);
795 
796 /* Miscellaneous support routines */
797 extern void spa_activate_mos_feature(spa_t *spa, const char *feature,
798     dmu_tx_t *tx);
799 extern void spa_deactivate_mos_feature(spa_t *spa, const char *feature);
800 extern int spa_rename(const char *oldname, const char *newname);
801 extern spa_t *spa_by_guid(uint64_t pool_guid, uint64_t device_guid);
802 extern boolean_t spa_guid_exists(uint64_t pool_guid, uint64_t device_guid);
803 extern char *spa_strdup(const char *);
804 extern void spa_strfree(char *);
805 extern uint64_t spa_get_random(uint64_t range);
806 extern uint64_t spa_generate_guid(spa_t *spa);
807 extern void snprintf_blkptr(char *buf, size_t buflen, const blkptr_t *bp);
808 extern void spa_freeze(spa_t *spa);
809 extern int spa_change_guid(spa_t *spa);
810 extern void spa_upgrade(spa_t *spa, uint64_t version);
811 extern void spa_evict_all(void);
812 extern vdev_t *spa_lookup_by_guid(spa_t *spa, uint64_t guid,
813     boolean_t l2cache);
814 extern boolean_t spa_has_spare(spa_t *, uint64_t guid);
815 extern uint64_t dva_get_dsize_sync(spa_t *spa, const dva_t *dva);
816 extern uint64_t bp_get_dsize_sync(spa_t *spa, const blkptr_t *bp);
817 extern uint64_t bp_get_dsize(spa_t *spa, const blkptr_t *bp);
818 extern boolean_t spa_has_slogs(spa_t *spa);
819 extern boolean_t spa_is_root(spa_t *spa);
820 extern boolean_t spa_writeable(spa_t *spa);
821 extern boolean_t spa_has_pending_synctask(spa_t *spa);
822 extern int spa_maxblocksize(spa_t *spa);
823 extern void zfs_blkptr_verify(spa_t *spa, const blkptr_t *bp);
824 
825 extern int spa_mode(spa_t *spa);
826 extern uint64_t strtonum(const char *str, char **nptr);
827 
828 extern char *spa_his_ievent_table[];
829 
830 extern void spa_history_create_obj(spa_t *spa, dmu_tx_t *tx);
831 extern int spa_history_get(spa_t *spa, uint64_t *offset, uint64_t *len_read,
832     char *his_buf);
833 extern int spa_history_log(spa_t *spa, const char *his_buf);
834 extern int spa_history_log_nvl(spa_t *spa, nvlist_t *nvl);
835 extern void spa_history_log_version(spa_t *spa, const char *operation);
836 extern void spa_history_log_internal(spa_t *spa, const char *operation,
837     dmu_tx_t *tx, const char *fmt, ...);
838 extern void spa_history_log_internal_ds(struct dsl_dataset *ds, const char *op,
839     dmu_tx_t *tx, const char *fmt, ...);
840 extern void spa_history_log_internal_dd(dsl_dir_t *dd, const char *operation,
841     dmu_tx_t *tx, const char *fmt, ...);
842 
843 /* error handling */
844 struct zbookmark_phys;
845 extern void spa_log_error(spa_t *spa, zio_t *zio);
846 extern void zfs_ereport_post(const char *class, spa_t *spa, vdev_t *vd,
847     zio_t *zio, uint64_t stateoroffset, uint64_t length);
848 extern void zfs_post_remove(spa_t *spa, vdev_t *vd);
849 extern void zfs_post_state_change(spa_t *spa, vdev_t *vd);
850 extern void zfs_post_autoreplace(spa_t *spa, vdev_t *vd);
851 extern uint64_t spa_get_errlog_size(spa_t *spa);
852 extern int spa_get_errlog(spa_t *spa, void *uaddr, size_t *count);
853 extern void spa_errlog_rotate(spa_t *spa);
854 extern void spa_errlog_drain(spa_t *spa);
855 extern void spa_errlog_sync(spa_t *spa, uint64_t txg);
856 extern void spa_get_errlists(spa_t *spa, avl_tree_t *last, avl_tree_t *scrub);
857 
858 /* vdev cache */
859 extern void vdev_cache_stat_init(void);
860 extern void vdev_cache_stat_fini(void);
861 
862 /* Initialization and termination */
863 extern void spa_init(int flags);
864 extern void spa_fini(void);
865 extern void spa_boot_init();
866 
867 /* properties */
868 extern int spa_prop_set(spa_t *spa, nvlist_t *nvp);
869 extern int spa_prop_get(spa_t *spa, nvlist_t **nvp);
870 extern void spa_prop_clear_bootfs(spa_t *spa, uint64_t obj, dmu_tx_t *tx);
871 extern void spa_configfile_set(spa_t *, nvlist_t *, boolean_t);
872 
873 /* asynchronous event notification */
874 extern void spa_event_notify(spa_t *spa, vdev_t *vdev, const char *name);
875 
876 #ifdef ZFS_DEBUG
877 #define	dprintf_bp(bp, fmt, ...) do {				\
878 	if (zfs_flags & ZFS_DEBUG_DPRINTF) {			\
879 	char *__blkbuf = kmem_alloc(BP_SPRINTF_LEN, KM_SLEEP);	\
880 	snprintf_blkptr(__blkbuf, BP_SPRINTF_LEN, (bp));	\
881 	dprintf(fmt " %s\n", __VA_ARGS__, __blkbuf);		\
882 	kmem_free(__blkbuf, BP_SPRINTF_LEN);			\
883 	} \
884 _NOTE(CONSTCOND) } while (0)
885 #else
886 #define	dprintf_bp(bp, fmt, ...)
887 #endif
888 
889 extern boolean_t spa_debug_enabled(spa_t *spa);
890 #define	spa_dbgmsg(spa, ...)			\
891 {						\
892 	if (spa_debug_enabled(spa))		\
893 		zfs_dbgmsg(__VA_ARGS__);	\
894 }
895 
896 extern int spa_mode_global;			/* mode, e.g. FREAD | FWRITE */
897 
898 #ifdef	__cplusplus
899 }
900 #endif
901 
902 #endif	/* _SYS_SPA_H */
903