xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/spa.h (revision 8c69cc8fbe729fa7b091e901c4b50508ccc6bb33)
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, 2016 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  * Copyright 2017 Joyent, Inc.
29  * Copyright (c) 2017 Datto Inc.
30  */
31 
32 #ifndef _SYS_SPA_H
33 #define	_SYS_SPA_H
34 
35 #include <sys/avl.h>
36 #include <sys/zfs_context.h>
37 #include <sys/nvpair.h>
38 #include <sys/sysmacros.h>
39 #include <sys/types.h>
40 #include <sys/fs/zfs.h>
41 #include <sys/dmu.h>
42 
43 #ifdef	__cplusplus
44 extern "C" {
45 #endif
46 
47 /*
48  * Forward references that lots of things need.
49  */
50 typedef struct spa spa_t;
51 typedef struct vdev vdev_t;
52 typedef struct metaslab metaslab_t;
53 typedef struct metaslab_group metaslab_group_t;
54 typedef struct metaslab_class metaslab_class_t;
55 typedef struct zio zio_t;
56 typedef struct zilog zilog_t;
57 typedef struct spa_aux_vdev spa_aux_vdev_t;
58 typedef struct ddt ddt_t;
59 typedef struct ddt_entry ddt_entry_t;
60 struct dsl_pool;
61 struct dsl_dataset;
62 
63 /*
64  * General-purpose 32-bit and 64-bit bitfield encodings.
65  */
66 #define	BF32_DECODE(x, low, len)	P2PHASE((x) >> (low), 1U << (len))
67 #define	BF64_DECODE(x, low, len)	P2PHASE((x) >> (low), 1ULL << (len))
68 #define	BF32_ENCODE(x, low, len)	(P2PHASE((x), 1U << (len)) << (low))
69 #define	BF64_ENCODE(x, low, len)	(P2PHASE((x), 1ULL << (len)) << (low))
70 
71 #define	BF32_GET(x, low, len)		BF32_DECODE(x, low, len)
72 #define	BF64_GET(x, low, len)		BF64_DECODE(x, low, len)
73 
74 #define	BF32_SET(x, low, len, val) do { \
75 	ASSERT3U(val, <, 1U << (len)); \
76 	ASSERT3U(low + len, <=, 32); \
77 	(x) ^= BF32_ENCODE((x >> low) ^ (val), low, len); \
78 _NOTE(CONSTCOND) } while (0)
79 
80 #define	BF64_SET(x, low, len, val) do { \
81 	ASSERT3U(val, <, 1ULL << (len)); \
82 	ASSERT3U(low + len, <=, 64); \
83 	((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len)); \
84 _NOTE(CONSTCOND) } while (0)
85 
86 #define	BF32_GET_SB(x, low, len, shift, bias)	\
87 	((BF32_GET(x, low, len) + (bias)) << (shift))
88 #define	BF64_GET_SB(x, low, len, shift, bias)	\
89 	((BF64_GET(x, low, len) + (bias)) << (shift))
90 
91 #define	BF32_SET_SB(x, low, len, shift, bias, val) do { \
92 	ASSERT(IS_P2ALIGNED(val, 1U << shift)); \
93 	ASSERT3S((val) >> (shift), >=, bias); \
94 	BF32_SET(x, low, len, ((val) >> (shift)) - (bias)); \
95 _NOTE(CONSTCOND) } while (0)
96 #define	BF64_SET_SB(x, low, len, shift, bias, val) do { \
97 	ASSERT(IS_P2ALIGNED(val, 1ULL << shift)); \
98 	ASSERT3S((val) >> (shift), >=, bias); \
99 	BF64_SET(x, low, len, ((val) >> (shift)) - (bias)); \
100 _NOTE(CONSTCOND) } while (0)
101 
102 /*
103  * We currently support block sizes from 512 bytes to 16MB.
104  * The benefits of larger blocks, and thus larger IO, need to be weighed
105  * against the cost of COWing a giant block to modify one byte, and the
106  * large latency of reading or writing a large block.
107  *
108  * Note that although blocks up to 16MB are supported, the recordsize
109  * property can not be set larger than zfs_max_recordsize (default 1MB).
110  * See the comment near zfs_max_recordsize in dsl_dataset.c for details.
111  *
112  * Note that although the LSIZE field of the blkptr_t can store sizes up
113  * to 32MB, the dnode's dn_datablkszsec can only store sizes up to
114  * 32MB - 512 bytes.  Therefore, we limit SPA_MAXBLOCKSIZE to 16MB.
115  */
116 #define	SPA_MINBLOCKSHIFT	9
117 #define	SPA_OLD_MAXBLOCKSHIFT	17
118 #define	SPA_MAXBLOCKSHIFT	24
119 #define	SPA_MINBLOCKSIZE	(1ULL << SPA_MINBLOCKSHIFT)
120 #define	SPA_OLD_MAXBLOCKSIZE	(1ULL << SPA_OLD_MAXBLOCKSHIFT)
121 #define	SPA_MAXBLOCKSIZE	(1ULL << SPA_MAXBLOCKSHIFT)
122 
123 /*
124  * Size of block to hold the configuration data (a packed nvlist)
125  */
126 #define	SPA_CONFIG_BLOCKSIZE	(1ULL << 14)
127 
128 /*
129  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
130  * The ASIZE encoding should be at least 64 times larger (6 more bits)
131  * to support up to 4-way RAID-Z mirror mode with worst-case gang block
132  * overhead, three DVAs per bp, plus one more bit in case we do anything
133  * else that expands the ASIZE.
134  */
135 #define	SPA_LSIZEBITS		16	/* LSIZE up to 32M (2^16 * 512)	*/
136 #define	SPA_PSIZEBITS		16	/* PSIZE up to 32M (2^16 * 512)	*/
137 #define	SPA_ASIZEBITS		24	/* ASIZE up to 64 times larger	*/
138 
139 #define	SPA_COMPRESSBITS	7
140 
141 /*
142  * All SPA data is represented by 128-bit data virtual addresses (DVAs).
143  * The members of the dva_t should be considered opaque outside the SPA.
144  */
145 typedef struct dva {
146 	uint64_t	dva_word[2];
147 } dva_t;
148 
149 /*
150  * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
151  */
152 typedef struct zio_cksum {
153 	uint64_t	zc_word[4];
154 } zio_cksum_t;
155 
156 /*
157  * Some checksums/hashes need a 256-bit initialization salt. This salt is kept
158  * secret and is suitable for use in MAC algorithms as the key.
159  */
160 typedef struct zio_cksum_salt {
161 	uint8_t		zcs_bytes[32];
162 } zio_cksum_salt_t;
163 
164 /*
165  * Each block is described by its DVAs, time of birth, checksum, etc.
166  * The word-by-word, bit-by-bit layout of the blkptr is as follows:
167  *
168  *	64	56	48	40	32	24	16	8	0
169  *	+-------+-------+-------+-------+-------+-------+-------+-------+
170  * 0	|		vdev1		| GRID  |	  ASIZE		|
171  *	+-------+-------+-------+-------+-------+-------+-------+-------+
172  * 1	|G|			 offset1				|
173  *	+-------+-------+-------+-------+-------+-------+-------+-------+
174  * 2	|		vdev2		| GRID  |	  ASIZE		|
175  *	+-------+-------+-------+-------+-------+-------+-------+-------+
176  * 3	|G|			 offset2				|
177  *	+-------+-------+-------+-------+-------+-------+-------+-------+
178  * 4	|		vdev3		| GRID  |	  ASIZE		|
179  *	+-------+-------+-------+-------+-------+-------+-------+-------+
180  * 5	|G|			 offset3				|
181  *	+-------+-------+-------+-------+-------+-------+-------+-------+
182  * 6	|BDX|lvl| type	| cksum |E| comp|    PSIZE	|     LSIZE	|
183  *	+-------+-------+-------+-------+-------+-------+-------+-------+
184  * 7	|			padding					|
185  *	+-------+-------+-------+-------+-------+-------+-------+-------+
186  * 8	|			padding					|
187  *	+-------+-------+-------+-------+-------+-------+-------+-------+
188  * 9	|			physical birth txg			|
189  *	+-------+-------+-------+-------+-------+-------+-------+-------+
190  * a	|			logical birth txg			|
191  *	+-------+-------+-------+-------+-------+-------+-------+-------+
192  * b	|			fill count				|
193  *	+-------+-------+-------+-------+-------+-------+-------+-------+
194  * c	|			checksum[0]				|
195  *	+-------+-------+-------+-------+-------+-------+-------+-------+
196  * d	|			checksum[1]				|
197  *	+-------+-------+-------+-------+-------+-------+-------+-------+
198  * e	|			checksum[2]				|
199  *	+-------+-------+-------+-------+-------+-------+-------+-------+
200  * f	|			checksum[3]				|
201  *	+-------+-------+-------+-------+-------+-------+-------+-------+
202  *
203  * Legend:
204  *
205  * vdev		virtual device ID
206  * offset	offset into virtual device
207  * LSIZE	logical size
208  * PSIZE	physical size (after compression)
209  * ASIZE	allocated size (including RAID-Z parity and gang block headers)
210  * GRID		RAID-Z layout information (reserved for future use)
211  * cksum	checksum function
212  * comp		compression function
213  * G		gang block indicator
214  * B		byteorder (endianness)
215  * D		dedup
216  * X		encryption (on version 30, which is not supported)
217  * E		blkptr_t contains embedded data (see below)
218  * lvl		level of indirection
219  * type		DMU object type
220  * phys birth	txg of block allocation; zero if same as logical birth txg
221  * log. birth	transaction group in which the block was logically born
222  * fill count	number of non-zero blocks under this bp
223  * checksum[4]	256-bit checksum of the data this bp describes
224  */
225 
226 /*
227  * "Embedded" blkptr_t's don't actually point to a block, instead they
228  * have a data payload embedded in the blkptr_t itself.  See the comment
229  * in blkptr.c for more details.
230  *
231  * The blkptr_t is laid out as follows:
232  *
233  *	64	56	48	40	32	24	16	8	0
234  *	+-------+-------+-------+-------+-------+-------+-------+-------+
235  * 0	|      payload                                                  |
236  * 1	|      payload                                                  |
237  * 2	|      payload                                                  |
238  * 3	|      payload                                                  |
239  * 4	|      payload                                                  |
240  * 5	|      payload                                                  |
241  *	+-------+-------+-------+-------+-------+-------+-------+-------+
242  * 6	|BDX|lvl| type	| etype |E| comp| PSIZE|              LSIZE	|
243  *	+-------+-------+-------+-------+-------+-------+-------+-------+
244  * 7	|      payload                                                  |
245  * 8	|      payload                                                  |
246  * 9	|      payload                                                  |
247  *	+-------+-------+-------+-------+-------+-------+-------+-------+
248  * a	|			logical birth txg			|
249  *	+-------+-------+-------+-------+-------+-------+-------+-------+
250  * b	|      payload                                                  |
251  * c	|      payload                                                  |
252  * d	|      payload                                                  |
253  * e	|      payload                                                  |
254  * f	|      payload                                                  |
255  *	+-------+-------+-------+-------+-------+-------+-------+-------+
256  *
257  * Legend:
258  *
259  * payload		contains the embedded data
260  * B (byteorder)	byteorder (endianness)
261  * D (dedup)		padding (set to zero)
262  * X			encryption (set to zero; see above)
263  * E (embedded)		set to one
264  * lvl			indirection level
265  * type			DMU object type
266  * etype		how to interpret embedded data (BP_EMBEDDED_TYPE_*)
267  * comp			compression function of payload
268  * PSIZE		size of payload after compression, in bytes
269  * LSIZE		logical size of payload, in bytes
270  *			note that 25 bits is enough to store the largest
271  *			"normal" BP's LSIZE (2^16 * 2^9) in bytes
272  * log. birth		transaction group in which the block was logically born
273  *
274  * Note that LSIZE and PSIZE are stored in bytes, whereas for non-embedded
275  * bp's they are stored in units of SPA_MINBLOCKSHIFT.
276  * Generally, the generic BP_GET_*() macros can be used on embedded BP's.
277  * The B, D, X, lvl, type, and comp fields are stored the same as with normal
278  * BP's so the BP_SET_* macros can be used with them.  etype, PSIZE, LSIZE must
279  * be set with the BPE_SET_* macros.  BP_SET_EMBEDDED() should be called before
280  * other macros, as they assert that they are only used on BP's of the correct
281  * "embedded-ness".
282  */
283 
284 #define	BPE_GET_ETYPE(bp)	\
285 	(ASSERT(BP_IS_EMBEDDED(bp)), \
286 	BF64_GET((bp)->blk_prop, 40, 8))
287 #define	BPE_SET_ETYPE(bp, t)	do { \
288 	ASSERT(BP_IS_EMBEDDED(bp)); \
289 	BF64_SET((bp)->blk_prop, 40, 8, t); \
290 _NOTE(CONSTCOND) } while (0)
291 
292 #define	BPE_GET_LSIZE(bp)	\
293 	(ASSERT(BP_IS_EMBEDDED(bp)), \
294 	BF64_GET_SB((bp)->blk_prop, 0, 25, 0, 1))
295 #define	BPE_SET_LSIZE(bp, x)	do { \
296 	ASSERT(BP_IS_EMBEDDED(bp)); \
297 	BF64_SET_SB((bp)->blk_prop, 0, 25, 0, 1, x); \
298 _NOTE(CONSTCOND) } while (0)
299 
300 #define	BPE_GET_PSIZE(bp)	\
301 	(ASSERT(BP_IS_EMBEDDED(bp)), \
302 	BF64_GET_SB((bp)->blk_prop, 25, 7, 0, 1))
303 #define	BPE_SET_PSIZE(bp, x)	do { \
304 	ASSERT(BP_IS_EMBEDDED(bp)); \
305 	BF64_SET_SB((bp)->blk_prop, 25, 7, 0, 1, x); \
306 _NOTE(CONSTCOND) } while (0)
307 
308 typedef enum bp_embedded_type {
309 	BP_EMBEDDED_TYPE_DATA,
310 	BP_EMBEDDED_TYPE_RESERVED, /* Reserved for an unintegrated feature. */
311 	NUM_BP_EMBEDDED_TYPES = BP_EMBEDDED_TYPE_RESERVED
312 } bp_embedded_type_t;
313 
314 #define	BPE_NUM_WORDS 14
315 #define	BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
316 #define	BPE_IS_PAYLOADWORD(bp, wp) \
317 	((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)
318 
319 #define	SPA_BLKPTRSHIFT	7		/* blkptr_t is 128 bytes	*/
320 #define	SPA_DVAS_PER_BP	3		/* Number of DVAs in a bp	*/
321 
322 /*
323  * A block is a hole when it has either 1) never been written to, or
324  * 2) is zero-filled. In both cases, ZFS can return all zeroes for all reads
325  * without physically allocating disk space. Holes are represented in the
326  * blkptr_t structure by zeroed blk_dva. Correct checking for holes is
327  * done through the BP_IS_HOLE macro. For holes, the logical size, level,
328  * DMU object type, and birth times are all also stored for holes that
329  * were written to at some point (i.e. were punched after having been filled).
330  */
331 typedef struct blkptr {
332 	dva_t		blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
333 	uint64_t	blk_prop;	/* size, compression, type, etc	    */
334 	uint64_t	blk_pad[2];	/* Extra space for the future	    */
335 	uint64_t	blk_phys_birth;	/* txg when block was allocated	    */
336 	uint64_t	blk_birth;	/* transaction group at birth	    */
337 	uint64_t	blk_fill;	/* fill count			    */
338 	zio_cksum_t	blk_cksum;	/* 256-bit checksum		    */
339 } blkptr_t;
340 
341 /*
342  * Macros to get and set fields in a bp or DVA.
343  */
344 #define	DVA_GET_ASIZE(dva)	\
345 	BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0)
346 #define	DVA_SET_ASIZE(dva, x)	\
347 	BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \
348 	SPA_MINBLOCKSHIFT, 0, x)
349 
350 #define	DVA_GET_GRID(dva)	BF64_GET((dva)->dva_word[0], 24, 8)
351 #define	DVA_SET_GRID(dva, x)	BF64_SET((dva)->dva_word[0], 24, 8, x)
352 
353 #define	DVA_GET_VDEV(dva)	BF64_GET((dva)->dva_word[0], 32, 32)
354 #define	DVA_SET_VDEV(dva, x)	BF64_SET((dva)->dva_word[0], 32, 32, x)
355 
356 #define	DVA_GET_OFFSET(dva)	\
357 	BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
358 #define	DVA_SET_OFFSET(dva, x)	\
359 	BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
360 
361 #define	DVA_GET_GANG(dva)	BF64_GET((dva)->dva_word[1], 63, 1)
362 #define	DVA_SET_GANG(dva, x)	BF64_SET((dva)->dva_word[1], 63, 1, x)
363 
364 #define	BP_GET_LSIZE(bp)	\
365 	(BP_IS_EMBEDDED(bp) ?	\
366 	(BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA ? BPE_GET_LSIZE(bp) : 0): \
367 	BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1))
368 #define	BP_SET_LSIZE(bp, x)	do { \
369 	ASSERT(!BP_IS_EMBEDDED(bp)); \
370 	BF64_SET_SB((bp)->blk_prop, \
371 	    0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x); \
372 _NOTE(CONSTCOND) } while (0)
373 
374 #define	BP_GET_PSIZE(bp)	\
375 	(BP_IS_EMBEDDED(bp) ? 0 : \
376 	BF64_GET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1))
377 #define	BP_SET_PSIZE(bp, x)	do { \
378 	ASSERT(!BP_IS_EMBEDDED(bp)); \
379 	BF64_SET_SB((bp)->blk_prop, \
380 	    16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x); \
381 _NOTE(CONSTCOND) } while (0)
382 
383 #define	BP_GET_COMPRESS(bp)		\
384 	BF64_GET((bp)->blk_prop, 32, SPA_COMPRESSBITS)
385 #define	BP_SET_COMPRESS(bp, x)		\
386 	BF64_SET((bp)->blk_prop, 32, SPA_COMPRESSBITS, x)
387 
388 #define	BP_IS_EMBEDDED(bp)		BF64_GET((bp)->blk_prop, 39, 1)
389 #define	BP_SET_EMBEDDED(bp, x)		BF64_SET((bp)->blk_prop, 39, 1, x)
390 
391 #define	BP_GET_CHECKSUM(bp)		\
392 	(BP_IS_EMBEDDED(bp) ? ZIO_CHECKSUM_OFF : \
393 	BF64_GET((bp)->blk_prop, 40, 8))
394 #define	BP_SET_CHECKSUM(bp, x)		do { \
395 	ASSERT(!BP_IS_EMBEDDED(bp)); \
396 	BF64_SET((bp)->blk_prop, 40, 8, x); \
397 _NOTE(CONSTCOND) } while (0)
398 
399 #define	BP_GET_TYPE(bp)			BF64_GET((bp)->blk_prop, 48, 8)
400 #define	BP_SET_TYPE(bp, x)		BF64_SET((bp)->blk_prop, 48, 8, x)
401 
402 #define	BP_GET_LEVEL(bp)		BF64_GET((bp)->blk_prop, 56, 5)
403 #define	BP_SET_LEVEL(bp, x)		BF64_SET((bp)->blk_prop, 56, 5, x)
404 
405 #define	BP_GET_DEDUP(bp)		BF64_GET((bp)->blk_prop, 62, 1)
406 #define	BP_SET_DEDUP(bp, x)		BF64_SET((bp)->blk_prop, 62, 1, x)
407 
408 #define	BP_GET_BYTEORDER(bp)		BF64_GET((bp)->blk_prop, 63, 1)
409 #define	BP_SET_BYTEORDER(bp, x)		BF64_SET((bp)->blk_prop, 63, 1, x)
410 
411 #define	BP_PHYSICAL_BIRTH(bp)		\
412 	(BP_IS_EMBEDDED(bp) ? 0 : \
413 	(bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)
414 
415 #define	BP_SET_BIRTH(bp, logical, physical)	\
416 {						\
417 	ASSERT(!BP_IS_EMBEDDED(bp));		\
418 	(bp)->blk_birth = (logical);		\
419 	(bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \
420 }
421 
422 #define	BP_GET_FILL(bp) (BP_IS_EMBEDDED(bp) ? 1 : (bp)->blk_fill)
423 
424 #define	BP_IS_METADATA(bp)	\
425 	(BP_GET_LEVEL(bp) > 0 || DMU_OT_IS_METADATA(BP_GET_TYPE(bp)))
426 
427 #define	BP_GET_ASIZE(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_GET_UCSIZE(bp)	\
434 	(BP_IS_METADATA(bp) ? BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp))
435 
436 #define	BP_GET_NDVAS(bp)	\
437 	(BP_IS_EMBEDDED(bp) ? 0 : \
438 	!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
439 	!!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
440 	!!DVA_GET_ASIZE(&(bp)->blk_dva[2]))
441 
442 #define	BP_COUNT_GANG(bp)	\
443 	(BP_IS_EMBEDDED(bp) ? 0 : \
444 	(DVA_GET_GANG(&(bp)->blk_dva[0]) + \
445 	DVA_GET_GANG(&(bp)->blk_dva[1]) + \
446 	DVA_GET_GANG(&(bp)->blk_dva[2])))
447 
448 #define	DVA_EQUAL(dva1, dva2)	\
449 	((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
450 	(dva1)->dva_word[0] == (dva2)->dva_word[0])
451 
452 #define	BP_EQUAL(bp1, bp2)	\
453 	(BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) &&	\
454 	(bp1)->blk_birth == (bp2)->blk_birth &&			\
455 	DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) &&	\
456 	DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) &&	\
457 	DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2]))
458 
459 #define	ZIO_CHECKSUM_EQUAL(zc1, zc2) \
460 	(0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
461 	((zc1).zc_word[1] - (zc2).zc_word[1]) | \
462 	((zc1).zc_word[2] - (zc2).zc_word[2]) | \
463 	((zc1).zc_word[3] - (zc2).zc_word[3])))
464 
465 #define	ZIO_CHECKSUM_IS_ZERO(zc) \
466 	(0 == ((zc)->zc_word[0] | (zc)->zc_word[1] | \
467 	(zc)->zc_word[2] | (zc)->zc_word[3]))
468 
469 #define	ZIO_CHECKSUM_BSWAP(zcp)					\
470 {								\
471 	(zcp)->zc_word[0] = BSWAP_64((zcp)->zc_word[0]);	\
472 	(zcp)->zc_word[1] = BSWAP_64((zcp)->zc_word[1]);	\
473 	(zcp)->zc_word[2] = BSWAP_64((zcp)->zc_word[2]);	\
474 	(zcp)->zc_word[3] = BSWAP_64((zcp)->zc_word[3]);	\
475 }
476 
477 
478 #define	DVA_IS_VALID(dva)	(DVA_GET_ASIZE(dva) != 0)
479 
480 #define	ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)	\
481 {						\
482 	(zcp)->zc_word[0] = w0;			\
483 	(zcp)->zc_word[1] = w1;			\
484 	(zcp)->zc_word[2] = w2;			\
485 	(zcp)->zc_word[3] = w3;			\
486 }
487 
488 #define	BP_IDENTITY(bp)		(ASSERT(!BP_IS_EMBEDDED(bp)), &(bp)->blk_dva[0])
489 #define	BP_IS_GANG(bp)		\
490 	(BP_IS_EMBEDDED(bp) ? B_FALSE : DVA_GET_GANG(BP_IDENTITY(bp)))
491 #define	DVA_IS_EMPTY(dva)	((dva)->dva_word[0] == 0ULL &&	\
492 				(dva)->dva_word[1] == 0ULL)
493 #define	BP_IS_HOLE(bp) \
494 	(!BP_IS_EMBEDDED(bp) && DVA_IS_EMPTY(BP_IDENTITY(bp)))
495 
496 /* BP_IS_RAIDZ(bp) assumes no block compression */
497 #define	BP_IS_RAIDZ(bp)		(DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \
498 				BP_GET_PSIZE(bp))
499 
500 #define	BP_ZERO(bp)				\
501 {						\
502 	(bp)->blk_dva[0].dva_word[0] = 0;	\
503 	(bp)->blk_dva[0].dva_word[1] = 0;	\
504 	(bp)->blk_dva[1].dva_word[0] = 0;	\
505 	(bp)->blk_dva[1].dva_word[1] = 0;	\
506 	(bp)->blk_dva[2].dva_word[0] = 0;	\
507 	(bp)->blk_dva[2].dva_word[1] = 0;	\
508 	(bp)->blk_prop = 0;			\
509 	(bp)->blk_pad[0] = 0;			\
510 	(bp)->blk_pad[1] = 0;			\
511 	(bp)->blk_phys_birth = 0;		\
512 	(bp)->blk_birth = 0;			\
513 	(bp)->blk_fill = 0;			\
514 	ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0);	\
515 }
516 
517 #ifdef _BIG_ENDIAN
518 #define	ZFS_HOST_BYTEORDER	(0ULL)
519 #else
520 #define	ZFS_HOST_BYTEORDER	(1ULL)
521 #endif
522 
523 #define	BP_SHOULD_BYTESWAP(bp)	(BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)
524 
525 #define	BP_SPRINTF_LEN	320
526 
527 /*
528  * This macro allows code sharing between zfs, libzpool, and mdb.
529  * 'func' is either snprintf() or mdb_snprintf().
530  * 'ws' (whitespace) can be ' ' for single-line format, '\n' for multi-line.
531  */
532 #define	SNPRINTF_BLKPTR(func, ws, buf, size, bp, type, checksum, compress) \
533 {									\
534 	static const char *copyname[] =					\
535 	    { "zero", "single", "double", "triple" };			\
536 	int len = 0;							\
537 	int copies = 0;							\
538 									\
539 	if (bp == NULL) {						\
540 		len += func(buf + len, size - len, "<NULL>");		\
541 	} else if (BP_IS_HOLE(bp)) {					\
542 		len += func(buf + len, size - len,			\
543 		    "HOLE [L%llu %s] "					\
544 		    "size=%llxL birth=%lluL",				\
545 		    (u_longlong_t)BP_GET_LEVEL(bp),			\
546 		    type,						\
547 		    (u_longlong_t)BP_GET_LSIZE(bp),			\
548 		    (u_longlong_t)bp->blk_birth);			\
549 	} else if (BP_IS_EMBEDDED(bp)) {				\
550 		len = func(buf + len, size - len,			\
551 		    "EMBEDDED [L%llu %s] et=%u %s "			\
552 		    "size=%llxL/%llxP birth=%lluL",			\
553 		    (u_longlong_t)BP_GET_LEVEL(bp),			\
554 		    type,						\
555 		    (int)BPE_GET_ETYPE(bp),				\
556 		    compress,						\
557 		    (u_longlong_t)BPE_GET_LSIZE(bp),			\
558 		    (u_longlong_t)BPE_GET_PSIZE(bp),			\
559 		    (u_longlong_t)bp->blk_birth);			\
560 	} else {							\
561 		for (int d = 0; d < BP_GET_NDVAS(bp); d++) {		\
562 			const dva_t *dva = &bp->blk_dva[d];		\
563 			if (DVA_IS_VALID(dva))				\
564 				copies++;				\
565 			len += func(buf + len, size - len,		\
566 			    "DVA[%d]=<%llu:%llx:%llx>%c", d,		\
567 			    (u_longlong_t)DVA_GET_VDEV(dva),		\
568 			    (u_longlong_t)DVA_GET_OFFSET(dva),		\
569 			    (u_longlong_t)DVA_GET_ASIZE(dva),		\
570 			    ws);					\
571 		}							\
572 		if (BP_IS_GANG(bp) &&					\
573 		    DVA_GET_ASIZE(&bp->blk_dva[2]) <=			\
574 		    DVA_GET_ASIZE(&bp->blk_dva[1]) / 2)			\
575 			copies--;					\
576 		len += func(buf + len, size - len,			\
577 		    "[L%llu %s] %s %s %s %s %s %s%c"			\
578 		    "size=%llxL/%llxP birth=%lluL/%lluP fill=%llu%c"	\
579 		    "cksum=%llx:%llx:%llx:%llx",			\
580 		    (u_longlong_t)BP_GET_LEVEL(bp),			\
581 		    type,						\
582 		    checksum,						\
583 		    compress,						\
584 		    BP_GET_BYTEORDER(bp) == 0 ? "BE" : "LE",		\
585 		    BP_IS_GANG(bp) ? "gang" : "contiguous",		\
586 		    BP_GET_DEDUP(bp) ? "dedup" : "unique",		\
587 		    copyname[copies],					\
588 		    ws,							\
589 		    (u_longlong_t)BP_GET_LSIZE(bp),			\
590 		    (u_longlong_t)BP_GET_PSIZE(bp),			\
591 		    (u_longlong_t)bp->blk_birth,			\
592 		    (u_longlong_t)BP_PHYSICAL_BIRTH(bp),		\
593 		    (u_longlong_t)BP_GET_FILL(bp),			\
594 		    ws,							\
595 		    (u_longlong_t)bp->blk_cksum.zc_word[0],		\
596 		    (u_longlong_t)bp->blk_cksum.zc_word[1],		\
597 		    (u_longlong_t)bp->blk_cksum.zc_word[2],		\
598 		    (u_longlong_t)bp->blk_cksum.zc_word[3]);		\
599 	}								\
600 	ASSERT(len < size);						\
601 }
602 
603 #define	BP_GET_BUFC_TYPE(bp)						\
604 	(BP_IS_METADATA(bp) ? ARC_BUFC_METADATA : ARC_BUFC_DATA)
605 
606 typedef enum spa_import_type {
607 	SPA_IMPORT_EXISTING,
608 	SPA_IMPORT_ASSEMBLE
609 } spa_import_type_t;
610 
611 /* state manipulation functions */
612 extern int spa_open(const char *pool, spa_t **, void *tag);
613 extern int spa_open_rewind(const char *pool, spa_t **, void *tag,
614     nvlist_t *policy, nvlist_t **config);
615 extern int spa_get_stats(const char *pool, nvlist_t **config, char *altroot,
616     size_t buflen);
617 extern int spa_create(const char *pool, nvlist_t *config, nvlist_t *props,
618     nvlist_t *zplprops);
619 extern int spa_import_rootpool(char *devpath, char *devid);
620 extern int spa_import(const char *pool, nvlist_t *config, nvlist_t *props,
621     uint64_t flags);
622 extern nvlist_t *spa_tryimport(nvlist_t *tryconfig);
623 extern int spa_destroy(char *pool);
624 extern int spa_export(char *pool, nvlist_t **oldconfig, boolean_t force,
625     boolean_t hardforce);
626 extern int spa_reset(char *pool);
627 extern void spa_async_request(spa_t *spa, int flag);
628 extern void spa_async_unrequest(spa_t *spa, int flag);
629 extern void spa_async_suspend(spa_t *spa);
630 extern void spa_async_resume(spa_t *spa);
631 extern spa_t *spa_inject_addref(char *pool);
632 extern void spa_inject_delref(spa_t *spa);
633 extern void spa_scan_stat_init(spa_t *spa);
634 extern int spa_scan_get_stats(spa_t *spa, pool_scan_stat_t *ps);
635 
636 #define	SPA_ASYNC_CONFIG_UPDATE	0x01
637 #define	SPA_ASYNC_REMOVE	0x02
638 #define	SPA_ASYNC_PROBE		0x04
639 #define	SPA_ASYNC_RESILVER_DONE	0x08
640 #define	SPA_ASYNC_RESILVER	0x10
641 #define	SPA_ASYNC_AUTOEXPAND	0x20
642 #define	SPA_ASYNC_REMOVE_DONE	0x40
643 #define	SPA_ASYNC_REMOVE_STOP	0x80
644 
645 /*
646  * Controls the behavior of spa_vdev_remove().
647  */
648 #define	SPA_REMOVE_UNSPARE	0x01
649 #define	SPA_REMOVE_DONE		0x02
650 
651 /* device manipulation */
652 extern int spa_vdev_add(spa_t *spa, nvlist_t *nvroot);
653 extern int spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot,
654     int replacing);
655 extern int spa_vdev_detach(spa_t *spa, uint64_t guid, uint64_t pguid,
656     int replace_done);
657 extern int spa_vdev_remove(spa_t *spa, uint64_t guid, boolean_t unspare);
658 extern boolean_t spa_vdev_remove_active(spa_t *spa);
659 extern int spa_vdev_setpath(spa_t *spa, uint64_t guid, const char *newpath);
660 extern int spa_vdev_setfru(spa_t *spa, uint64_t guid, const char *newfru);
661 extern int spa_vdev_split_mirror(spa_t *spa, char *newname, nvlist_t *config,
662     nvlist_t *props, boolean_t exp);
663 
664 /* spare state (which is global across all pools) */
665 extern void spa_spare_add(vdev_t *vd);
666 extern void spa_spare_remove(vdev_t *vd);
667 extern boolean_t spa_spare_exists(uint64_t guid, uint64_t *pool, int *refcnt);
668 extern void spa_spare_activate(vdev_t *vd);
669 
670 /* L2ARC state (which is global across all pools) */
671 extern void spa_l2cache_add(vdev_t *vd);
672 extern void spa_l2cache_remove(vdev_t *vd);
673 extern boolean_t spa_l2cache_exists(uint64_t guid, uint64_t *pool);
674 extern void spa_l2cache_activate(vdev_t *vd);
675 extern void spa_l2cache_drop(spa_t *spa);
676 
677 /* scanning */
678 extern int spa_scan(spa_t *spa, pool_scan_func_t func);
679 extern int spa_scan_stop(spa_t *spa);
680 extern int spa_scrub_pause_resume(spa_t *spa, pool_scrub_cmd_t flag);
681 
682 /* spa syncing */
683 extern void spa_sync(spa_t *spa, uint64_t txg); /* only for DMU use */
684 extern void spa_sync_allpools(void);
685 
686 /* spa namespace global mutex */
687 extern kmutex_t spa_namespace_lock;
688 
689 /*
690  * SPA configuration functions in spa_config.c
691  */
692 
693 #define	SPA_CONFIG_UPDATE_POOL	0
694 #define	SPA_CONFIG_UPDATE_VDEVS	1
695 
696 extern void spa_config_sync(spa_t *, boolean_t, boolean_t);
697 extern void spa_config_load(void);
698 extern nvlist_t *spa_all_configs(uint64_t *);
699 extern void spa_config_set(spa_t *spa, nvlist_t *config);
700 extern nvlist_t *spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg,
701     int getstats);
702 extern void spa_config_update(spa_t *spa, int what);
703 
704 /*
705  * Miscellaneous SPA routines in spa_misc.c
706  */
707 
708 /* Namespace manipulation */
709 extern spa_t *spa_lookup(const char *name);
710 extern spa_t *spa_add(const char *name, nvlist_t *config, const char *altroot);
711 extern void spa_remove(spa_t *spa);
712 extern spa_t *spa_next(spa_t *prev);
713 
714 /* Refcount functions */
715 extern void spa_open_ref(spa_t *spa, void *tag);
716 extern void spa_close(spa_t *spa, void *tag);
717 extern void spa_async_close(spa_t *spa, void *tag);
718 extern boolean_t spa_refcount_zero(spa_t *spa);
719 
720 #define	SCL_NONE	0x00
721 #define	SCL_CONFIG	0x01
722 #define	SCL_STATE	0x02
723 #define	SCL_L2ARC	0x04		/* hack until L2ARC 2.0 */
724 #define	SCL_ALLOC	0x08
725 #define	SCL_ZIO		0x10
726 #define	SCL_FREE	0x20
727 #define	SCL_VDEV	0x40
728 #define	SCL_LOCKS	7
729 #define	SCL_ALL		((1 << SCL_LOCKS) - 1)
730 #define	SCL_STATE_ALL	(SCL_STATE | SCL_L2ARC | SCL_ZIO)
731 
732 /* Pool configuration locks */
733 extern int spa_config_tryenter(spa_t *spa, int locks, void *tag, krw_t rw);
734 extern void spa_config_enter(spa_t *spa, int locks, void *tag, krw_t rw);
735 extern void spa_config_exit(spa_t *spa, int locks, void *tag);
736 extern int spa_config_held(spa_t *spa, int locks, krw_t rw);
737 
738 /* Pool vdev add/remove lock */
739 extern uint64_t spa_vdev_enter(spa_t *spa);
740 extern uint64_t spa_vdev_config_enter(spa_t *spa);
741 extern void spa_vdev_config_exit(spa_t *spa, vdev_t *vd, uint64_t txg,
742     int error, char *tag);
743 extern int spa_vdev_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error);
744 
745 /* Pool vdev state change lock */
746 extern void spa_vdev_state_enter(spa_t *spa, int oplock);
747 extern int spa_vdev_state_exit(spa_t *spa, vdev_t *vd, int error);
748 
749 /* Log state */
750 typedef enum spa_log_state {
751 	SPA_LOG_UNKNOWN = 0,	/* unknown log state */
752 	SPA_LOG_MISSING,	/* missing log(s) */
753 	SPA_LOG_CLEAR,		/* clear the log(s) */
754 	SPA_LOG_GOOD,		/* log(s) are good */
755 } spa_log_state_t;
756 
757 extern spa_log_state_t spa_get_log_state(spa_t *spa);
758 extern void spa_set_log_state(spa_t *spa, spa_log_state_t state);
759 extern int spa_offline_log(spa_t *spa);
760 
761 /* Log claim callback */
762 extern void spa_claim_notify(zio_t *zio);
763 
764 /* Accessor functions */
765 extern boolean_t spa_shutting_down(spa_t *spa);
766 extern struct dsl_pool *spa_get_dsl(spa_t *spa);
767 extern boolean_t spa_is_initializing(spa_t *spa);
768 extern blkptr_t *spa_get_rootblkptr(spa_t *spa);
769 extern void spa_set_rootblkptr(spa_t *spa, const blkptr_t *bp);
770 extern void spa_altroot(spa_t *, char *, size_t);
771 extern int spa_sync_pass(spa_t *spa);
772 extern char *spa_name(spa_t *spa);
773 extern uint64_t spa_guid(spa_t *spa);
774 extern uint64_t spa_load_guid(spa_t *spa);
775 extern uint64_t spa_last_synced_txg(spa_t *spa);
776 extern uint64_t spa_first_txg(spa_t *spa);
777 extern uint64_t spa_syncing_txg(spa_t *spa);
778 extern uint64_t spa_final_dirty_txg(spa_t *spa);
779 extern uint64_t spa_version(spa_t *spa);
780 extern pool_state_t spa_state(spa_t *spa);
781 extern spa_load_state_t spa_load_state(spa_t *spa);
782 extern uint64_t spa_freeze_txg(spa_t *spa);
783 extern uint64_t spa_get_worst_case_asize(spa_t *spa, uint64_t lsize);
784 extern uint64_t spa_get_dspace(spa_t *spa);
785 extern uint64_t spa_get_slop_space(spa_t *spa);
786 extern void spa_update_dspace(spa_t *spa);
787 extern uint64_t spa_version(spa_t *spa);
788 extern boolean_t spa_deflate(spa_t *spa);
789 extern metaslab_class_t *spa_normal_class(spa_t *spa);
790 extern metaslab_class_t *spa_log_class(spa_t *spa);
791 extern void spa_evicting_os_register(spa_t *, objset_t *os);
792 extern void spa_evicting_os_deregister(spa_t *, objset_t *os);
793 extern void spa_evicting_os_wait(spa_t *spa);
794 extern int spa_max_replication(spa_t *spa);
795 extern int spa_prev_software_version(spa_t *spa);
796 extern int spa_busy(void);
797 extern uint8_t spa_get_failmode(spa_t *spa);
798 extern boolean_t spa_suspended(spa_t *spa);
799 extern uint64_t spa_bootfs(spa_t *spa);
800 extern uint64_t spa_delegation(spa_t *spa);
801 extern objset_t *spa_meta_objset(spa_t *spa);
802 extern uint64_t spa_deadman_synctime(spa_t *spa);
803 
804 /* Miscellaneous support routines */
805 extern void spa_activate_mos_feature(spa_t *spa, const char *feature,
806     dmu_tx_t *tx);
807 extern void spa_deactivate_mos_feature(spa_t *spa, const char *feature);
808 extern int spa_rename(const char *oldname, const char *newname);
809 extern spa_t *spa_by_guid(uint64_t pool_guid, uint64_t device_guid);
810 extern boolean_t spa_guid_exists(uint64_t pool_guid, uint64_t device_guid);
811 extern char *spa_strdup(const char *);
812 extern void spa_strfree(char *);
813 extern uint64_t spa_get_random(uint64_t range);
814 extern uint64_t spa_generate_guid(spa_t *spa);
815 extern void snprintf_blkptr(char *buf, size_t buflen, const blkptr_t *bp);
816 extern void spa_freeze(spa_t *spa);
817 extern int spa_change_guid(spa_t *spa);
818 extern void spa_upgrade(spa_t *spa, uint64_t version);
819 extern void spa_evict_all(void);
820 extern vdev_t *spa_lookup_by_guid(spa_t *spa, uint64_t guid,
821     boolean_t l2cache);
822 extern boolean_t spa_has_spare(spa_t *, uint64_t guid);
823 extern uint64_t dva_get_dsize_sync(spa_t *spa, const dva_t *dva);
824 extern uint64_t bp_get_dsize_sync(spa_t *spa, const blkptr_t *bp);
825 extern uint64_t bp_get_dsize(spa_t *spa, const blkptr_t *bp);
826 extern boolean_t spa_has_slogs(spa_t *spa);
827 extern boolean_t spa_is_root(spa_t *spa);
828 extern boolean_t spa_writeable(spa_t *spa);
829 extern boolean_t spa_has_pending_synctask(spa_t *spa);
830 extern int spa_maxblocksize(spa_t *spa);
831 extern void zfs_blkptr_verify(spa_t *spa, const blkptr_t *bp);
832 
833 extern int spa_mode(spa_t *spa);
834 extern uint64_t zfs_strtonum(const char *str, char **nptr);
835 
836 extern char *spa_his_ievent_table[];
837 
838 extern void spa_history_create_obj(spa_t *spa, dmu_tx_t *tx);
839 extern int spa_history_get(spa_t *spa, uint64_t *offset, uint64_t *len_read,
840     char *his_buf);
841 extern int spa_history_log(spa_t *spa, const char *his_buf);
842 extern int spa_history_log_nvl(spa_t *spa, nvlist_t *nvl);
843 extern void spa_history_log_version(spa_t *spa, const char *operation);
844 extern void spa_history_log_internal(spa_t *spa, const char *operation,
845     dmu_tx_t *tx, const char *fmt, ...);
846 extern void spa_history_log_internal_ds(struct dsl_dataset *ds, const char *op,
847     dmu_tx_t *tx, const char *fmt, ...);
848 extern void spa_history_log_internal_dd(dsl_dir_t *dd, const char *operation,
849     dmu_tx_t *tx, const char *fmt, ...);
850 
851 /* error handling */
852 struct zbookmark_phys;
853 extern void spa_log_error(spa_t *spa, zio_t *zio);
854 extern void zfs_ereport_post(const char *class, spa_t *spa, vdev_t *vd,
855     zio_t *zio, uint64_t stateoroffset, uint64_t length);
856 extern void zfs_post_remove(spa_t *spa, vdev_t *vd);
857 extern void zfs_post_state_change(spa_t *spa, vdev_t *vd);
858 extern void zfs_post_autoreplace(spa_t *spa, vdev_t *vd);
859 extern uint64_t spa_get_errlog_size(spa_t *spa);
860 extern int spa_get_errlog(spa_t *spa, void *uaddr, size_t *count);
861 extern void spa_errlog_rotate(spa_t *spa);
862 extern void spa_errlog_drain(spa_t *spa);
863 extern void spa_errlog_sync(spa_t *spa, uint64_t txg);
864 extern void spa_get_errlists(spa_t *spa, avl_tree_t *last, avl_tree_t *scrub);
865 
866 /* vdev cache */
867 extern void vdev_cache_stat_init(void);
868 extern void vdev_cache_stat_fini(void);
869 
870 /* Initialization and termination */
871 extern void spa_init(int flags);
872 extern void spa_fini(void);
873 extern void spa_boot_init(void);
874 
875 /* properties */
876 extern int spa_prop_set(spa_t *spa, nvlist_t *nvp);
877 extern int spa_prop_get(spa_t *spa, nvlist_t **nvp);
878 extern void spa_prop_clear_bootfs(spa_t *spa, uint64_t obj, dmu_tx_t *tx);
879 extern void spa_configfile_set(spa_t *, nvlist_t *, boolean_t);
880 
881 /* asynchronous event notification */
882 extern void spa_event_notify(spa_t *spa, vdev_t *vdev, nvlist_t *hist_nvl,
883     const char *name);
884 
885 #ifdef ZFS_DEBUG
886 #define	dprintf_bp(bp, fmt, ...) do {				\
887 	if (zfs_flags & ZFS_DEBUG_DPRINTF) {			\
888 	char *__blkbuf = kmem_alloc(BP_SPRINTF_LEN, KM_SLEEP);	\
889 	snprintf_blkptr(__blkbuf, BP_SPRINTF_LEN, (bp));	\
890 	dprintf(fmt " %s\n", __VA_ARGS__, __blkbuf);		\
891 	kmem_free(__blkbuf, BP_SPRINTF_LEN);			\
892 	} \
893 _NOTE(CONSTCOND) } while (0)
894 #else
895 #define	dprintf_bp(bp, fmt, ...)
896 #endif
897 
898 extern boolean_t spa_debug_enabled(spa_t *spa);
899 #define	spa_dbgmsg(spa, ...)			\
900 {						\
901 	if (spa_debug_enabled(spa))		\
902 		zfs_dbgmsg(__VA_ARGS__);	\
903 }
904 
905 extern int spa_mode_global;			/* mode, e.g. FREAD | FWRITE */
906 
907 #ifdef	__cplusplus
908 }
909 #endif
910 
911 #endif	/* _SYS_SPA_H */
912