xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/spa.h (revision 88f8b78a88cbdc6d8c1af5c3e54bc49d25095c98)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef _SYS_SPA_H
28 #define	_SYS_SPA_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #include <sys/avl.h>
33 #include <sys/zfs_context.h>
34 #include <sys/nvpair.h>
35 #include <sys/sysmacros.h>
36 #include <sys/types.h>
37 #include <sys/fs/zfs.h>
38 
39 #ifdef	__cplusplus
40 extern "C" {
41 #endif
42 
43 /*
44  * Forward references that lots of things need.
45  */
46 typedef struct spa spa_t;
47 typedef struct vdev vdev_t;
48 typedef struct metaslab metaslab_t;
49 typedef struct zilog zilog_t;
50 typedef struct traverse_handle traverse_handle_t;
51 struct dsl_pool;
52 
53 /*
54  * General-purpose 32-bit and 64-bit bitfield encodings.
55  */
56 #define	BF32_DECODE(x, low, len)	P2PHASE((x) >> (low), 1U << (len))
57 #define	BF64_DECODE(x, low, len)	P2PHASE((x) >> (low), 1ULL << (len))
58 #define	BF32_ENCODE(x, low, len)	(P2PHASE((x), 1U << (len)) << (low))
59 #define	BF64_ENCODE(x, low, len)	(P2PHASE((x), 1ULL << (len)) << (low))
60 
61 #define	BF32_GET(x, low, len)		BF32_DECODE(x, low, len)
62 #define	BF64_GET(x, low, len)		BF64_DECODE(x, low, len)
63 
64 #define	BF32_SET(x, low, len, val)	\
65 	((x) ^= BF32_ENCODE((x >> low) ^ val, low, len))
66 #define	BF64_SET(x, low, len, val)	\
67 	((x) ^= BF64_ENCODE((x >> low) ^ val, low, len))
68 
69 #define	BF32_GET_SB(x, low, len, shift, bias)	\
70 	((BF32_GET(x, low, len) + (bias)) << (shift))
71 #define	BF64_GET_SB(x, low, len, shift, bias)	\
72 	((BF64_GET(x, low, len) + (bias)) << (shift))
73 
74 #define	BF32_SET_SB(x, low, len, shift, bias, val)	\
75 	BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
76 #define	BF64_SET_SB(x, low, len, shift, bias, val)	\
77 	BF64_SET(x, low, len, ((val) >> (shift)) - (bias))
78 
79 /*
80  * We currently support nine block sizes, from 512 bytes to 128K.
81  * We could go higher, but the benefits are near-zero and the cost
82  * of COWing a giant block to modify one byte would become excessive.
83  */
84 #define	SPA_MINBLOCKSHIFT	9
85 #define	SPA_MAXBLOCKSHIFT	17
86 #define	SPA_MINBLOCKSIZE	(1ULL << SPA_MINBLOCKSHIFT)
87 #define	SPA_MAXBLOCKSIZE	(1ULL << SPA_MAXBLOCKSHIFT)
88 
89 #define	SPA_BLOCKSIZES		(SPA_MAXBLOCKSHIFT - SPA_MINBLOCKSHIFT + 1)
90 
91 /*
92  * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
93  * The ASIZE encoding should be at least 64 times larger (6 more bits)
94  * to support up to 4-way RAID-Z mirror mode with worst-case gang block
95  * overhead, three DVAs per bp, plus one more bit in case we do anything
96  * else that expands the ASIZE.
97  */
98 #define	SPA_LSIZEBITS		16	/* LSIZE up to 32M (2^16 * 512)	*/
99 #define	SPA_PSIZEBITS		16	/* PSIZE up to 32M (2^16 * 512)	*/
100 #define	SPA_ASIZEBITS		24	/* ASIZE up to 64 times larger	*/
101 
102 /*
103  * All SPA data is represented by 128-bit data virtual addresses (DVAs).
104  * The members of the dva_t should be considered opaque outside the SPA.
105  */
106 typedef struct dva {
107 	uint64_t	dva_word[2];
108 } dva_t;
109 
110 /*
111  * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
112  */
113 typedef struct zio_cksum {
114 	uint64_t	zc_word[4];
115 } zio_cksum_t;
116 
117 /*
118  * Each block is described by its DVAs, time of birth, checksum, etc.
119  * The word-by-word, bit-by-bit layout of the blkptr is as follows:
120  *
121  *	64	56	48	40	32	24	16	8	0
122  *	+-------+-------+-------+-------+-------+-------+-------+-------+
123  * 0	|		vdev1		| GRID  |	  ASIZE		|
124  *	+-------+-------+-------+-------+-------+-------+-------+-------+
125  * 1	|G|			 offset1				|
126  *	+-------+-------+-------+-------+-------+-------+-------+-------+
127  * 2	|		vdev2		| GRID  |	  ASIZE		|
128  *	+-------+-------+-------+-------+-------+-------+-------+-------+
129  * 3	|G|			 offset2				|
130  *	+-------+-------+-------+-------+-------+-------+-------+-------+
131  * 4	|		vdev3		| GRID  |	  ASIZE		|
132  *	+-------+-------+-------+-------+-------+-------+-------+-------+
133  * 5	|G|			 offset3				|
134  *	+-------+-------+-------+-------+-------+-------+-------+-------+
135  * 6	|E| lvl | type	| cksum | comp	|     PSIZE	|     LSIZE	|
136  *	+-------+-------+-------+-------+-------+-------+-------+-------+
137  * 7	|			padding					|
138  *	+-------+-------+-------+-------+-------+-------+-------+-------+
139  * 8	|			padding					|
140  *	+-------+-------+-------+-------+-------+-------+-------+-------+
141  * 9	|			padding					|
142  *	+-------+-------+-------+-------+-------+-------+-------+-------+
143  * a	|			birth txg				|
144  *	+-------+-------+-------+-------+-------+-------+-------+-------+
145  * b	|			fill count				|
146  *	+-------+-------+-------+-------+-------+-------+-------+-------+
147  * c	|			checksum[0]				|
148  *	+-------+-------+-------+-------+-------+-------+-------+-------+
149  * d	|			checksum[1]				|
150  *	+-------+-------+-------+-------+-------+-------+-------+-------+
151  * e	|			checksum[2]				|
152  *	+-------+-------+-------+-------+-------+-------+-------+-------+
153  * f	|			checksum[3]				|
154  *	+-------+-------+-------+-------+-------+-------+-------+-------+
155  *
156  * Legend:
157  *
158  * vdev		virtual device ID
159  * offset	offset into virtual device
160  * LSIZE	logical size
161  * PSIZE	physical size (after compression)
162  * ASIZE	allocated size (including RAID-Z parity and gang block headers)
163  * GRID		RAID-Z layout information (reserved for future use)
164  * cksum	checksum function
165  * comp		compression function
166  * G		gang block indicator
167  * E		endianness
168  * type		DMU object type
169  * lvl		level of indirection
170  * birth txg	transaction group in which the block was born
171  * fill count	number of non-zero blocks under this bp
172  * checksum[4]	256-bit checksum of the data this bp describes
173  */
174 typedef struct blkptr {
175 	dva_t		blk_dva[3];	/* 128-bit Data Virtual Address	*/
176 	uint64_t	blk_prop;	/* size, compression, type, etc	*/
177 	uint64_t	blk_pad[3];	/* Extra space for the future	*/
178 	uint64_t	blk_birth;	/* transaction group at birth	*/
179 	uint64_t	blk_fill;	/* fill count			*/
180 	zio_cksum_t	blk_cksum;	/* 256-bit checksum		*/
181 } blkptr_t;
182 
183 #define	SPA_BLKPTRSHIFT	7		/* blkptr_t is 128 bytes	*/
184 #define	SPA_DVAS_PER_BP	3		/* Number of DVAs in a bp	*/
185 
186 /*
187  * Macros to get and set fields in a bp or DVA.
188  */
189 #define	DVA_GET_ASIZE(dva)	\
190 	BF64_GET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0)
191 #define	DVA_SET_ASIZE(dva, x)	\
192 	BF64_SET_SB((dva)->dva_word[0], 0, 24, SPA_MINBLOCKSHIFT, 0, x)
193 
194 #define	DVA_GET_GRID(dva)	BF64_GET((dva)->dva_word[0], 24, 8)
195 #define	DVA_SET_GRID(dva, x)	BF64_SET((dva)->dva_word[0], 24, 8, x)
196 
197 #define	DVA_GET_VDEV(dva)	BF64_GET((dva)->dva_word[0], 32, 32)
198 #define	DVA_SET_VDEV(dva, x)	BF64_SET((dva)->dva_word[0], 32, 32, x)
199 
200 #define	DVA_GET_OFFSET(dva)	\
201 	BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
202 #define	DVA_SET_OFFSET(dva, x)	\
203 	BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)
204 
205 #define	DVA_GET_GANG(dva)	BF64_GET((dva)->dva_word[1], 63, 1)
206 #define	DVA_SET_GANG(dva, x)	BF64_SET((dva)->dva_word[1], 63, 1, x)
207 
208 #define	BP_GET_LSIZE(bp)	\
209 	(BP_IS_HOLE(bp) ? 0 : \
210 	BF64_GET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1))
211 #define	BP_SET_LSIZE(bp, x)	\
212 	BF64_SET_SB((bp)->blk_prop, 0, 16, SPA_MINBLOCKSHIFT, 1, x)
213 
214 #define	BP_GET_PSIZE(bp)	\
215 	BF64_GET_SB((bp)->blk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1)
216 #define	BP_SET_PSIZE(bp, x)	\
217 	BF64_SET_SB((bp)->blk_prop, 16, 16, SPA_MINBLOCKSHIFT, 1, x)
218 
219 #define	BP_GET_COMPRESS(bp)	BF64_GET((bp)->blk_prop, 32, 8)
220 #define	BP_SET_COMPRESS(bp, x)	BF64_SET((bp)->blk_prop, 32, 8, x)
221 
222 #define	BP_GET_CHECKSUM(bp)	BF64_GET((bp)->blk_prop, 40, 8)
223 #define	BP_SET_CHECKSUM(bp, x)	BF64_SET((bp)->blk_prop, 40, 8, x)
224 
225 #define	BP_GET_TYPE(bp)		BF64_GET((bp)->blk_prop, 48, 8)
226 #define	BP_SET_TYPE(bp, x)	BF64_SET((bp)->blk_prop, 48, 8, x)
227 
228 #define	BP_GET_LEVEL(bp)	BF64_GET((bp)->blk_prop, 56, 5)
229 #define	BP_SET_LEVEL(bp, x)	BF64_SET((bp)->blk_prop, 56, 5, x)
230 
231 #define	BP_GET_BYTEORDER(bp)	(0 - BF64_GET((bp)->blk_prop, 63, 1))
232 #define	BP_SET_BYTEORDER(bp, x)	BF64_SET((bp)->blk_prop, 63, 1, x)
233 
234 #define	BP_GET_ASIZE(bp)	\
235 	(DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
236 	DVA_GET_ASIZE(&(bp)->blk_dva[2]))
237 
238 #define	DVA_EQUAL(dva1, dva2)	\
239 	((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
240 	(dva1)->dva_word[0] == (dva2)->dva_word[0])
241 
242 #define	DVA_IS_VALID(dva)	(DVA_GET_ASIZE(dva) != 0)
243 
244 #define	ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)	\
245 {						\
246 	(zcp)->zc_word[0] = w0;			\
247 	(zcp)->zc_word[1] = w1;			\
248 	(zcp)->zc_word[2] = w2;			\
249 	(zcp)->zc_word[3] = w3;			\
250 }
251 
252 #define	BP_IS_HOLE(bp)		((bp)->blk_birth == 0)
253 
254 #define	BP_IDENTITY(bp)		(&(bp)->blk_dva[0])
255 
256 #define	BP_ZERO(bp)				\
257 {						\
258 	(bp)->blk_dva[0].dva_word[0] = 0;	\
259 	(bp)->blk_dva[0].dva_word[1] = 0;	\
260 	(bp)->blk_dva[1].dva_word[0] = 0;	\
261 	(bp)->blk_dva[1].dva_word[1] = 0;	\
262 	(bp)->blk_dva[2].dva_word[0] = 0;	\
263 	(bp)->blk_dva[2].dva_word[1] = 0;	\
264 	(bp)->blk_prop = 0;			\
265 	(bp)->blk_pad[0] = 0;			\
266 	(bp)->blk_pad[1] = 0;			\
267 	(bp)->blk_pad[2] = 0;			\
268 	(bp)->blk_birth = 0;			\
269 	(bp)->blk_fill = 0;			\
270 	ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0);	\
271 }
272 
273 /*
274  * Note: the byteorder is either 0 or -1, both of which are palindromes.
275  * This simplifies the endianness handling a bit.
276  */
277 #ifdef _BIG_ENDIAN
278 #define	ZFS_HOST_BYTEORDER	(0ULL)
279 #else
280 #define	ZFS_HOST_BYTEORDER	(-1ULL)
281 #endif
282 
283 #define	BP_SHOULD_BYTESWAP(bp)	(BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)
284 
285 #define	BP_SPRINTF_LEN	256
286 
287 #include <sys/dmu.h>
288 
289 /*
290  * Routines found in spa.c
291  */
292 
293 /* state manipulation functions */
294 extern int spa_open(const char *pool, spa_t **, void *tag);
295 extern int spa_get_stats(const char *pool, nvlist_t **config);
296 extern int spa_create(const char *pool, nvlist_t *config, char *altroot);
297 extern int spa_import(const char *pool, nvlist_t *config, char *altroot);
298 extern nvlist_t *spa_tryimport(nvlist_t *tryconfig);
299 extern int spa_destroy(char *pool);
300 extern int spa_export(char *pool);
301 
302 /* device manipulation */
303 extern int spa_vdev_add(spa_t *spa, nvlist_t *nvroot);
304 extern int spa_vdev_add_unlocked(spa_t *spa, nvlist_t *nvroot);
305 extern int spa_vdev_attach(spa_t *spa, const char *path, nvlist_t *nvroot,
306     int replacing);
307 extern int spa_vdev_detach(spa_t *spa, const char *path, uint64_t guid,
308     int replace_done);
309 extern void spa_vdev_replace_done(spa_t *spa);
310 
311 /* scrubbing */
312 extern int spa_scrub(spa_t *spa, pool_scrub_type_t type, boolean_t force);
313 extern void spa_scrub_suspend(spa_t *spa);
314 extern void spa_scrub_resume(spa_t *spa);
315 extern void spa_scrub_restart(spa_t *spa, uint64_t txg);
316 
317 /* spa syncing */
318 extern void spa_sync(spa_t *spa, uint64_t txg); /* only for DMU use */
319 extern void spa_sync_allpools(void);
320 
321 /*
322  * SPA configuration functions in spa_config.c
323  */
324 extern void spa_config_sync(void);
325 extern void spa_config_load(void);
326 extern nvlist_t *spa_all_configs(uint64_t *);
327 extern void spa_config_set(spa_t *spa, nvlist_t *config);
328 extern nvlist_t *spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg,
329     int getstats);
330 
331 /*
332  * Miscellaneous SPA routines in spa_misc.c
333  */
334 
335 /* Namespace manipulation */
336 extern spa_t *spa_lookup(const char *name);
337 extern spa_t *spa_add(const char *name);
338 extern void spa_remove(spa_t *spa);
339 extern spa_t *spa_next(spa_t *prev);
340 
341 /* Refcount functions */
342 extern void spa_open_ref(spa_t *spa, void *tag);
343 extern void spa_close(spa_t *spa, void *tag);
344 extern boolean_t spa_refcount_zero(spa_t *spa);
345 
346 /* Pool configuration lock */
347 extern void spa_config_enter(spa_t *spa, krw_t rw);
348 extern void spa_config_exit(spa_t *spa);
349 extern boolean_t spa_config_held(spa_t *spa, krw_t rw);
350 
351 /* Pool vdev add/remove lock */
352 extern uint64_t spa_vdev_enter(spa_t *spa);
353 extern int spa_vdev_exit(spa_t *spa, vdev_t *vd, uint64_t txg, int error);
354 
355 /* Accessor functions */
356 extern krwlock_t *spa_traverse_rwlock(spa_t *spa);
357 extern int spa_traverse_wanted(spa_t *spa);
358 extern struct dsl_pool *spa_get_dsl(spa_t *spa);
359 extern blkptr_t *spa_get_rootblkptr(spa_t *spa);
360 extern void spa_set_rootblkptr(spa_t *spa, const blkptr_t *bp);
361 extern void spa_altroot(spa_t *, char *, size_t);
362 extern int spa_sync_pass(spa_t *spa);
363 extern char *spa_name(spa_t *spa);
364 extern uint64_t spa_guid(spa_t *spa);
365 extern uint64_t spa_last_synced_txg(spa_t *spa);
366 extern uint64_t spa_first_txg(spa_t *spa);
367 extern int spa_state(spa_t *spa);
368 extern uint64_t spa_freeze_txg(spa_t *spa);
369 struct metaslab_class;
370 extern struct metaslab_class *spa_metaslab_class_select(spa_t *spa);
371 extern uint64_t spa_get_alloc(spa_t *spa);
372 extern uint64_t spa_get_space(spa_t *spa);
373 extern uint64_t spa_get_asize(spa_t *spa, uint64_t lsize);
374 extern int spa_busy(void);
375 
376 /* Miscellaneous support routines */
377 extern int spa_rename(const char *oldname, const char *newname);
378 extern boolean_t spa_guid_exists(uint64_t pool_guid, uint64_t device_guid);
379 extern char *spa_strdup(const char *);
380 extern void spa_strfree(char *);
381 extern uint64_t spa_get_random(uint64_t range);
382 extern void sprintf_blkptr(char *buf, int len, blkptr_t *bp);
383 extern void spa_freeze(spa_t *spa);
384 extern void spa_evict_all(void);
385 
386 /* Initialization and termination */
387 extern void spa_init(int flags);
388 extern void spa_fini(void);
389 
390 #ifdef ZFS_DEBUG
391 #define	dprintf_bp(bp, fmt, ...) do {			\
392 	if (zfs_flags & ZFS_DEBUG_DPRINTF) { 		\
393 	char __blkbuf[BP_SPRINTF_LEN];			\
394 	sprintf_blkptr(__blkbuf, BP_SPRINTF_LEN, (bp));	\
395 	dprintf(fmt " %s\n", __VA_ARGS__, __blkbuf);	\
396 	} \
397 _NOTE(CONSTCOND) } while (0)
398 #else
399 #define	dprintf_bp(bp, fmt, ...)
400 #endif
401 
402 extern int spa_mode;			/* mode, e.g. FREAD | FWRITE */
403 
404 #ifdef	__cplusplus
405 }
406 #endif
407 
408 #endif	/* _SYS_SPA_H */
409