xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/zio.h (revision 44ecc5327ab4ce0750dcca2a17e05566bf2812e2)
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 /*
23  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 #ifndef _ZIO_H
27 #define	_ZIO_H
28 
29 #include <sys/zfs_context.h>
30 #include <sys/spa.h>
31 #include <sys/txg.h>
32 #include <sys/avl.h>
33 #include <sys/fs/zfs.h>
34 #include <sys/zio_impl.h>
35 
36 #ifdef	__cplusplus
37 extern "C" {
38 #endif
39 
40 /*
41  * Embedded checksum
42  */
43 #define	ZEC_MAGIC	0x210da7ab10c7a11ULL
44 
45 typedef struct zio_eck {
46 	uint64_t	zec_magic;	/* for validation, endianness	*/
47 	zio_cksum_t	zec_cksum;	/* 256-bit checksum		*/
48 } zio_eck_t;
49 
50 /*
51  * Gang block headers are self-checksumming and contain an array
52  * of block pointers.
53  */
54 #define	SPA_GANGBLOCKSIZE	SPA_MINBLOCKSIZE
55 #define	SPA_GBH_NBLKPTRS	((SPA_GANGBLOCKSIZE - \
56 	sizeof (zio_eck_t)) / sizeof (blkptr_t))
57 #define	SPA_GBH_FILLER		((SPA_GANGBLOCKSIZE - \
58 	sizeof (zio_eck_t) - \
59 	(SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
60 	sizeof (uint64_t))
61 
62 typedef struct zio_gbh {
63 	blkptr_t		zg_blkptr[SPA_GBH_NBLKPTRS];
64 	uint64_t		zg_filler[SPA_GBH_FILLER];
65 	zio_eck_t		zg_tail;
66 } zio_gbh_phys_t;
67 
68 enum zio_checksum {
69 	ZIO_CHECKSUM_INHERIT = 0,
70 	ZIO_CHECKSUM_ON,
71 	ZIO_CHECKSUM_OFF,
72 	ZIO_CHECKSUM_LABEL,
73 	ZIO_CHECKSUM_GANG_HEADER,
74 	ZIO_CHECKSUM_ZILOG,
75 	ZIO_CHECKSUM_FLETCHER_2,
76 	ZIO_CHECKSUM_FLETCHER_4,
77 	ZIO_CHECKSUM_SHA256,
78 	ZIO_CHECKSUM_ZILOG2,
79 	ZIO_CHECKSUM_FUNCTIONS
80 };
81 
82 #define	ZIO_CHECKSUM_ON_VALUE	ZIO_CHECKSUM_FLETCHER_4
83 #define	ZIO_CHECKSUM_DEFAULT	ZIO_CHECKSUM_ON
84 
85 #define	ZIO_CHECKSUM_MASK	0xffULL
86 #define	ZIO_CHECKSUM_VERIFY	(1 << 8)
87 
88 #define	ZIO_DEDUPCHECKSUM	ZIO_CHECKSUM_SHA256
89 #define	ZIO_DEDUPDITTO_MIN	100
90 
91 enum zio_compress {
92 	ZIO_COMPRESS_INHERIT = 0,
93 	ZIO_COMPRESS_ON,
94 	ZIO_COMPRESS_OFF,
95 	ZIO_COMPRESS_LZJB,
96 	ZIO_COMPRESS_EMPTY,
97 	ZIO_COMPRESS_GZIP_1,
98 	ZIO_COMPRESS_GZIP_2,
99 	ZIO_COMPRESS_GZIP_3,
100 	ZIO_COMPRESS_GZIP_4,
101 	ZIO_COMPRESS_GZIP_5,
102 	ZIO_COMPRESS_GZIP_6,
103 	ZIO_COMPRESS_GZIP_7,
104 	ZIO_COMPRESS_GZIP_8,
105 	ZIO_COMPRESS_GZIP_9,
106 	ZIO_COMPRESS_ZLE,
107 	ZIO_COMPRESS_FUNCTIONS
108 };
109 
110 #define	ZIO_COMPRESS_ON_VALUE	ZIO_COMPRESS_LZJB
111 #define	ZIO_COMPRESS_DEFAULT	ZIO_COMPRESS_OFF
112 
113 #define	BOOTFS_COMPRESS_VALID(compress)			\
114 	((compress) == ZIO_COMPRESS_LZJB ||		\
115 	((compress) == ZIO_COMPRESS_ON &&		\
116 	ZIO_COMPRESS_ON_VALUE == ZIO_COMPRESS_LZJB) ||	\
117 	(compress) == ZIO_COMPRESS_OFF)
118 
119 #define	ZIO_FAILURE_MODE_WAIT		0
120 #define	ZIO_FAILURE_MODE_CONTINUE	1
121 #define	ZIO_FAILURE_MODE_PANIC		2
122 
123 #define	ZIO_PRIORITY_NOW		(zio_priority_table[0])
124 #define	ZIO_PRIORITY_SYNC_READ		(zio_priority_table[1])
125 #define	ZIO_PRIORITY_SYNC_WRITE		(zio_priority_table[2])
126 #define	ZIO_PRIORITY_LOG_WRITE		(zio_priority_table[3])
127 #define	ZIO_PRIORITY_CACHE_FILL		(zio_priority_table[4])
128 #define	ZIO_PRIORITY_AGG		(zio_priority_table[5])
129 #define	ZIO_PRIORITY_FREE		(zio_priority_table[6])
130 #define	ZIO_PRIORITY_ASYNC_WRITE	(zio_priority_table[7])
131 #define	ZIO_PRIORITY_ASYNC_READ		(zio_priority_table[8])
132 #define	ZIO_PRIORITY_RESILVER		(zio_priority_table[9])
133 #define	ZIO_PRIORITY_SCRUB		(zio_priority_table[10])
134 #define	ZIO_PRIORITY_DDT_PREFETCH	(zio_priority_table[11])
135 #define	ZIO_PRIORITY_TABLE_SIZE		12
136 
137 #define	ZIO_PIPELINE_CONTINUE		0x100
138 #define	ZIO_PIPELINE_STOP		0x101
139 
140 enum zio_flag {
141 	/*
142 	 * Flags inherited by gang, ddt, and vdev children,
143 	 * and that must be equal for two zios to aggregate
144 	 */
145 	ZIO_FLAG_DONT_AGGREGATE	= 1 << 0,
146 	ZIO_FLAG_IO_REPAIR	= 1 << 1,
147 	ZIO_FLAG_SELF_HEAL	= 1 << 2,
148 	ZIO_FLAG_RESILVER	= 1 << 3,
149 	ZIO_FLAG_SCRUB		= 1 << 4,
150 	ZIO_FLAG_SCAN_THREAD	= 1 << 5,
151 
152 #define	ZIO_FLAG_AGG_INHERIT	(ZIO_FLAG_CANFAIL - 1)
153 
154 	/*
155 	 * Flags inherited by ddt, gang, and vdev children.
156 	 */
157 	ZIO_FLAG_CANFAIL	= 1 << 6,	/* must be first for INHERIT */
158 	ZIO_FLAG_SPECULATIVE	= 1 << 7,
159 	ZIO_FLAG_CONFIG_WRITER	= 1 << 8,
160 	ZIO_FLAG_DONT_RETRY	= 1 << 9,
161 	ZIO_FLAG_DONT_CACHE	= 1 << 10,
162 	ZIO_FLAG_NODATA		= 1 << 11,
163 	ZIO_FLAG_INDUCE_DAMAGE	= 1 << 12,
164 
165 #define	ZIO_FLAG_DDT_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
166 #define	ZIO_FLAG_GANG_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
167 
168 	/*
169 	 * Flags inherited by vdev children.
170 	 */
171 	ZIO_FLAG_IO_RETRY	= 1 << 13,	/* must be first for INHERIT */
172 	ZIO_FLAG_PROBE		= 1 << 14,
173 	ZIO_FLAG_TRYHARD	= 1 << 15,
174 	ZIO_FLAG_OPTIONAL	= 1 << 16,
175 
176 #define	ZIO_FLAG_VDEV_INHERIT	(ZIO_FLAG_DONT_QUEUE - 1)
177 
178 	/*
179 	 * Flags not inherited by any children.
180 	 */
181 	ZIO_FLAG_DONT_QUEUE	= 1 << 17,	/* must be first for INHERIT */
182 	ZIO_FLAG_DONT_PROPAGATE	= 1 << 18,
183 	ZIO_FLAG_IO_BYPASS	= 1 << 19,
184 	ZIO_FLAG_IO_REWRITE	= 1 << 20,
185 	ZIO_FLAG_RAW		= 1 << 21,
186 	ZIO_FLAG_GANG_CHILD	= 1 << 22,
187 	ZIO_FLAG_DDT_CHILD	= 1 << 23,
188 	ZIO_FLAG_GODFATHER	= 1 << 24
189 };
190 
191 #define	ZIO_FLAG_MUSTSUCCEED		0
192 
193 #define	ZIO_DDT_CHILD_FLAGS(zio)				\
194 	(((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |		\
195 	ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
196 
197 #define	ZIO_GANG_CHILD_FLAGS(zio)				\
198 	(((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |		\
199 	ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
200 
201 #define	ZIO_VDEV_CHILD_FLAGS(zio)				\
202 	(((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |		\
203 	ZIO_FLAG_CANFAIL)
204 
205 enum zio_child {
206 	ZIO_CHILD_VDEV = 0,
207 	ZIO_CHILD_GANG,
208 	ZIO_CHILD_DDT,
209 	ZIO_CHILD_LOGICAL,
210 	ZIO_CHILD_TYPES
211 };
212 
213 enum zio_wait_type {
214 	ZIO_WAIT_READY = 0,
215 	ZIO_WAIT_DONE,
216 	ZIO_WAIT_TYPES
217 };
218 
219 /*
220  * We'll take the unused errnos, 'EBADE' and 'EBADR' (from the Convergent
221  * graveyard) to indicate checksum errors and fragmentation.
222  */
223 #define	ECKSUM	EBADE
224 #define	EFRAGS	EBADR
225 
226 typedef void zio_done_func_t(zio_t *zio);
227 
228 extern uint8_t zio_priority_table[ZIO_PRIORITY_TABLE_SIZE];
229 extern char *zio_type_name[ZIO_TYPES];
230 
231 /*
232  * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
233  * identifies any block in the pool.  By convention, the meta-objset (MOS)
234  * is objset 0, and the meta-dnode is object 0.  This covers all blocks
235  * except root blocks and ZIL blocks, which are defined as follows:
236  *
237  * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
238  * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
239  * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
240  *
241  * Note: this structure is called a bookmark because its original purpose
242  * was to remember where to resume a pool-wide traverse.
243  *
244  * Note: this structure is passed between userland and the kernel.
245  * Therefore it must not change size or alignment between 32/64 bit
246  * compilation options.
247  */
248 typedef struct zbookmark {
249 	uint64_t	zb_objset;
250 	uint64_t	zb_object;
251 	int64_t		zb_level;
252 	uint64_t	zb_blkid;
253 } zbookmark_t;
254 
255 #define	SET_BOOKMARK(zb, objset, object, level, blkid)  \
256 {                                                       \
257 	(zb)->zb_objset = objset;                       \
258 	(zb)->zb_object = object;                       \
259 	(zb)->zb_level = level;                         \
260 	(zb)->zb_blkid = blkid;                         \
261 }
262 
263 #define	ZB_DESTROYED_OBJSET	(-1ULL)
264 
265 #define	ZB_ROOT_OBJECT		(0ULL)
266 #define	ZB_ROOT_LEVEL		(-1LL)
267 #define	ZB_ROOT_BLKID		(0ULL)
268 
269 #define	ZB_ZIL_OBJECT		(0ULL)
270 #define	ZB_ZIL_LEVEL		(-2LL)
271 
272 typedef struct zio_prop {
273 	enum zio_checksum	zp_checksum;
274 	enum zio_compress	zp_compress;
275 	dmu_object_type_t	zp_type;
276 	uint8_t			zp_level;
277 	uint8_t			zp_copies;
278 	uint8_t			zp_dedup;
279 	uint8_t			zp_dedup_verify;
280 } zio_prop_t;
281 
282 typedef struct zio_cksum_report zio_cksum_report_t;
283 
284 typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
285     const void *good_data);
286 typedef void zio_cksum_free_f(void *cbdata, size_t size);
287 
288 struct zio_bad_cksum;				/* defined in zio_checksum.h */
289 
290 struct zio_cksum_report {
291 	struct zio_cksum_report *zcr_next;
292 	nvlist_t		*zcr_ereport;
293 	nvlist_t		*zcr_detector;
294 	void			*zcr_cbdata;
295 	size_t			zcr_cbinfo;	/* passed to zcr_free() */
296 	uint64_t		zcr_align;
297 	uint64_t		zcr_length;
298 	zio_cksum_finish_f	*zcr_finish;
299 	zio_cksum_free_f	*zcr_free;
300 
301 	/* internal use only */
302 	struct zio_bad_cksum	*zcr_ckinfo;	/* information from failure */
303 };
304 
305 typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,
306     void *arg);
307 
308 zio_vsd_cksum_report_f	zio_vsd_default_cksum_report;
309 
310 typedef struct zio_vsd_ops {
311 	zio_done_func_t		*vsd_free;
312 	zio_vsd_cksum_report_f	*vsd_cksum_report;
313 } zio_vsd_ops_t;
314 
315 typedef struct zio_gang_node {
316 	zio_gbh_phys_t		*gn_gbh;
317 	struct zio_gang_node	*gn_child[SPA_GBH_NBLKPTRS];
318 } zio_gang_node_t;
319 
320 typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
321     zio_gang_node_t *gn, void *data);
322 
323 typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);
324 
325 typedef struct zio_transform {
326 	void			*zt_orig_data;
327 	uint64_t		zt_orig_size;
328 	uint64_t		zt_bufsize;
329 	zio_transform_func_t	*zt_transform;
330 	struct zio_transform	*zt_next;
331 } zio_transform_t;
332 
333 typedef int zio_pipe_stage_t(zio_t *zio);
334 
335 /*
336  * The io_reexecute flags are distinct from io_flags because the child must
337  * be able to propagate them to the parent.  The normal io_flags are local
338  * to the zio, not protected by any lock, and not modifiable by children;
339  * the reexecute flags are protected by io_lock, modifiable by children,
340  * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
341  */
342 #define	ZIO_REEXECUTE_NOW	0x01
343 #define	ZIO_REEXECUTE_SUSPEND	0x02
344 
345 typedef struct zio_link {
346 	zio_t		*zl_parent;
347 	zio_t		*zl_child;
348 	list_node_t	zl_parent_node;
349 	list_node_t	zl_child_node;
350 } zio_link_t;
351 
352 struct zio {
353 	/* Core information about this I/O */
354 	zbookmark_t	io_bookmark;
355 	zio_prop_t	io_prop;
356 	zio_type_t	io_type;
357 	enum zio_child	io_child_type;
358 	int		io_cmd;
359 	uint8_t		io_priority;
360 	uint8_t		io_reexecute;
361 	uint8_t		io_state[ZIO_WAIT_TYPES];
362 	uint64_t	io_txg;
363 	spa_t		*io_spa;
364 	blkptr_t	*io_bp;
365 	blkptr_t	*io_bp_override;
366 	blkptr_t	io_bp_copy;
367 	list_t		io_parent_list;
368 	list_t		io_child_list;
369 	zio_link_t	*io_walk_link;
370 	zio_t		*io_logical;
371 	zio_transform_t *io_transform_stack;
372 
373 	/* Callback info */
374 	zio_done_func_t	*io_ready;
375 	zio_done_func_t	*io_done;
376 	void		*io_private;
377 	int64_t		io_prev_space_delta;	/* DMU private */
378 	blkptr_t	io_bp_orig;
379 
380 	/* Data represented by this I/O */
381 	void		*io_data;
382 	void		*io_orig_data;
383 	uint64_t	io_size;
384 	uint64_t	io_orig_size;
385 
386 	/* Stuff for the vdev stack */
387 	vdev_t		*io_vd;
388 	void		*io_vsd;
389 	const zio_vsd_ops_t *io_vsd_ops;
390 
391 	uint64_t	io_offset;
392 	uint64_t	io_deadline;
393 	avl_node_t	io_offset_node;
394 	avl_node_t	io_deadline_node;
395 	avl_tree_t	*io_vdev_tree;
396 
397 	/* Internal pipeline state */
398 	enum zio_flag	io_flags;
399 	enum zio_stage	io_stage;
400 	enum zio_stage	io_pipeline;
401 	enum zio_flag	io_orig_flags;
402 	enum zio_stage	io_orig_stage;
403 	enum zio_stage	io_orig_pipeline;
404 	int		io_error;
405 	int		io_child_error[ZIO_CHILD_TYPES];
406 	uint64_t	io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];
407 	uint64_t	io_child_count;
408 	uint64_t	io_parent_count;
409 	uint64_t	*io_stall;
410 	zio_t		*io_gang_leader;
411 	zio_gang_node_t	*io_gang_tree;
412 	void		*io_executor;
413 	void		*io_waiter;
414 	kmutex_t	io_lock;
415 	kcondvar_t	io_cv;
416 
417 	/* FMA state */
418 	zio_cksum_report_t *io_cksum_report;
419 	uint64_t	io_ena;
420 };
421 
422 extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
423     zio_done_func_t *done, void *private, enum zio_flag flags);
424 
425 extern zio_t *zio_root(spa_t *spa,
426     zio_done_func_t *done, void *private, enum zio_flag flags);
427 
428 extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
429     uint64_t size, zio_done_func_t *done, void *private,
430     int priority, enum zio_flag flags, const zbookmark_t *zb);
431 
432 extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
433     void *data, uint64_t size, const zio_prop_t *zp,
434     zio_done_func_t *ready, zio_done_func_t *done, void *private,
435     int priority, enum zio_flag flags, const zbookmark_t *zb);
436 
437 extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
438     void *data, uint64_t size, zio_done_func_t *done, void *private,
439     int priority, enum zio_flag flags, zbookmark_t *zb);
440 
441 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies);
442 
443 extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
444 
445 extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
446     const blkptr_t *bp,
447     zio_done_func_t *done, void *private, enum zio_flag flags);
448 
449 extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
450     zio_done_func_t *done, void *private, int priority, enum zio_flag flags);
451 
452 extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
453     uint64_t size, void *data, int checksum,
454     zio_done_func_t *done, void *private, int priority, enum zio_flag flags,
455     boolean_t labels);
456 
457 extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
458     uint64_t size, void *data, int checksum,
459     zio_done_func_t *done, void *private, int priority, enum zio_flag flags,
460     boolean_t labels);
461 
462 extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
463     const blkptr_t *bp, enum zio_flag flags);
464 
465 extern int zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp,
466     blkptr_t *old_bp, uint64_t size, boolean_t use_slog);
467 extern void zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp);
468 extern void zio_flush(zio_t *zio, vdev_t *vd);
469 extern void zio_shrink(zio_t *zio, uint64_t size);
470 
471 extern int zio_wait(zio_t *zio);
472 extern void zio_nowait(zio_t *zio);
473 extern void zio_execute(zio_t *zio);
474 extern void zio_interrupt(zio_t *zio);
475 
476 extern zio_t *zio_walk_parents(zio_t *cio);
477 extern zio_t *zio_walk_children(zio_t *pio);
478 extern zio_t *zio_unique_parent(zio_t *cio);
479 extern void zio_add_child(zio_t *pio, zio_t *cio);
480 
481 extern void *zio_buf_alloc(size_t size);
482 extern void zio_buf_free(void *buf, size_t size);
483 extern void *zio_data_buf_alloc(size_t size);
484 extern void zio_data_buf_free(void *buf, size_t size);
485 
486 extern void zio_resubmit_stage_async(void *);
487 
488 extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
489     uint64_t offset, void *data, uint64_t size, int type, int priority,
490     enum zio_flag flags, zio_done_func_t *done, void *private);
491 
492 extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
493     void *data, uint64_t size, int type, int priority,
494     enum zio_flag flags, zio_done_func_t *done, void *private);
495 
496 extern void zio_vdev_io_bypass(zio_t *zio);
497 extern void zio_vdev_io_reissue(zio_t *zio);
498 extern void zio_vdev_io_redone(zio_t *zio);
499 
500 extern void zio_checksum_verified(zio_t *zio);
501 extern int zio_worst_error(int e1, int e2);
502 
503 extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
504     enum zio_checksum parent);
505 extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
506     enum zio_checksum child, enum zio_checksum parent);
507 extern enum zio_compress zio_compress_select(enum zio_compress child,
508     enum zio_compress parent);
509 
510 extern void zio_suspend(spa_t *spa, zio_t *zio);
511 extern int zio_resume(spa_t *spa);
512 extern void zio_resume_wait(spa_t *spa);
513 
514 /*
515  * Initial setup and teardown.
516  */
517 extern void zio_init(void);
518 extern void zio_fini(void);
519 
520 /*
521  * Fault injection
522  */
523 struct zinject_record;
524 extern uint32_t zio_injection_enabled;
525 extern int zio_inject_fault(char *name, int flags, int *id,
526     struct zinject_record *record);
527 extern int zio_inject_list_next(int *id, char *name, size_t buflen,
528     struct zinject_record *record);
529 extern int zio_clear_fault(int id);
530 extern void zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type);
531 extern int zio_handle_fault_injection(zio_t *zio, int error);
532 extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
533 extern int zio_handle_label_injection(zio_t *zio, int error);
534 extern void zio_handle_ignored_writes(zio_t *zio);
535 
536 /*
537  * Checksum ereport functions
538  */
539 extern void zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd, struct zio *zio,
540     uint64_t offset, uint64_t length, void *arg, struct zio_bad_cksum *info);
541 extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
542     const void *good_data, const void *bad_data, boolean_t drop_if_identical);
543 
544 extern void zfs_ereport_send_interim_checksum(zio_cksum_report_t *report);
545 extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
546 
547 /* If we have the good data in hand, this function can be used */
548 extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
549     struct zio *zio, uint64_t offset, uint64_t length,
550     const void *good_data, const void *bad_data, struct zio_bad_cksum *info);
551 
552 /* Called from spa_sync(), but primarily an injection handler */
553 extern void spa_handle_ignored_writes(spa_t *spa);
554 
555 #ifdef	__cplusplus
556 }
557 #endif
558 
559 #endif	/* _ZIO_H */
560