xref: /titanic_50/usr/src/uts/common/fs/zfs/sys/zio.h (revision ead9bb4b1be81d7bbf8ed86ee41d6c1e58b069a3)
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  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
27  */
28 
29 #ifndef _ZIO_H
30 #define	_ZIO_H
31 
32 #include <sys/zfs_context.h>
33 #include <sys/spa.h>
34 #include <sys/txg.h>
35 #include <sys/avl.h>
36 #include <sys/fs/zfs.h>
37 #include <sys/zio_impl.h>
38 
39 #ifdef	__cplusplus
40 extern "C" {
41 #endif
42 
43 /*
44  * Embedded checksum
45  */
46 #define	ZEC_MAGIC	0x210da7ab10c7a11ULL
47 
48 typedef struct zio_eck {
49 	uint64_t	zec_magic;	/* for validation, endianness	*/
50 	zio_cksum_t	zec_cksum;	/* 256-bit checksum		*/
51 } zio_eck_t;
52 
53 /*
54  * Gang block headers are self-checksumming and contain an array
55  * of block pointers.
56  */
57 #define	SPA_GANGBLOCKSIZE	SPA_MINBLOCKSIZE
58 #define	SPA_GBH_NBLKPTRS	((SPA_GANGBLOCKSIZE - \
59 	sizeof (zio_eck_t)) / sizeof (blkptr_t))
60 #define	SPA_GBH_FILLER		((SPA_GANGBLOCKSIZE - \
61 	sizeof (zio_eck_t) - \
62 	(SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
63 	sizeof (uint64_t))
64 
65 typedef struct zio_gbh {
66 	blkptr_t		zg_blkptr[SPA_GBH_NBLKPTRS];
67 	uint64_t		zg_filler[SPA_GBH_FILLER];
68 	zio_eck_t		zg_tail;
69 } zio_gbh_phys_t;
70 
71 enum zio_checksum {
72 	ZIO_CHECKSUM_INHERIT = 0,
73 	ZIO_CHECKSUM_ON,
74 	ZIO_CHECKSUM_OFF,
75 	ZIO_CHECKSUM_LABEL,
76 	ZIO_CHECKSUM_GANG_HEADER,
77 	ZIO_CHECKSUM_ZILOG,
78 	ZIO_CHECKSUM_FLETCHER_2,
79 	ZIO_CHECKSUM_FLETCHER_4,
80 	ZIO_CHECKSUM_SHA256,
81 	ZIO_CHECKSUM_ZILOG2,
82 	ZIO_CHECKSUM_FUNCTIONS
83 };
84 
85 #define	ZIO_CHECKSUM_ON_VALUE	ZIO_CHECKSUM_FLETCHER_4
86 #define	ZIO_CHECKSUM_DEFAULT	ZIO_CHECKSUM_ON
87 
88 #define	ZIO_CHECKSUM_MASK	0xffULL
89 #define	ZIO_CHECKSUM_VERIFY	(1 << 8)
90 
91 #define	ZIO_DEDUPCHECKSUM	ZIO_CHECKSUM_SHA256
92 #define	ZIO_DEDUPDITTO_MIN	100
93 
94 enum zio_compress {
95 	ZIO_COMPRESS_INHERIT = 0,
96 	ZIO_COMPRESS_ON,
97 	ZIO_COMPRESS_OFF,
98 	ZIO_COMPRESS_LZJB,
99 	ZIO_COMPRESS_EMPTY,
100 	ZIO_COMPRESS_GZIP_1,
101 	ZIO_COMPRESS_GZIP_2,
102 	ZIO_COMPRESS_GZIP_3,
103 	ZIO_COMPRESS_GZIP_4,
104 	ZIO_COMPRESS_GZIP_5,
105 	ZIO_COMPRESS_GZIP_6,
106 	ZIO_COMPRESS_GZIP_7,
107 	ZIO_COMPRESS_GZIP_8,
108 	ZIO_COMPRESS_GZIP_9,
109 	ZIO_COMPRESS_ZLE,
110 	ZIO_COMPRESS_FUNCTIONS
111 };
112 
113 #define	ZIO_COMPRESS_ON_VALUE	ZIO_COMPRESS_LZJB
114 #define	ZIO_COMPRESS_DEFAULT	ZIO_COMPRESS_OFF
115 
116 #define	BOOTFS_COMPRESS_VALID(compress)			\
117 	((compress) == ZIO_COMPRESS_LZJB ||		\
118 	((compress) == ZIO_COMPRESS_ON &&		\
119 	ZIO_COMPRESS_ON_VALUE == ZIO_COMPRESS_LZJB) ||	\
120 	(compress) == ZIO_COMPRESS_OFF)
121 
122 #define	ZIO_FAILURE_MODE_WAIT		0
123 #define	ZIO_FAILURE_MODE_CONTINUE	1
124 #define	ZIO_FAILURE_MODE_PANIC		2
125 
126 #define	ZIO_PRIORITY_NOW		(zio_priority_table[0])
127 #define	ZIO_PRIORITY_SYNC_READ		(zio_priority_table[1])
128 #define	ZIO_PRIORITY_SYNC_WRITE		(zio_priority_table[2])
129 #define	ZIO_PRIORITY_LOG_WRITE		(zio_priority_table[3])
130 #define	ZIO_PRIORITY_CACHE_FILL		(zio_priority_table[4])
131 #define	ZIO_PRIORITY_AGG		(zio_priority_table[5])
132 #define	ZIO_PRIORITY_FREE		(zio_priority_table[6])
133 #define	ZIO_PRIORITY_ASYNC_WRITE	(zio_priority_table[7])
134 #define	ZIO_PRIORITY_ASYNC_READ		(zio_priority_table[8])
135 #define	ZIO_PRIORITY_RESILVER		(zio_priority_table[9])
136 #define	ZIO_PRIORITY_SCRUB		(zio_priority_table[10])
137 #define	ZIO_PRIORITY_DDT_PREFETCH	(zio_priority_table[11])
138 #define	ZIO_PRIORITY_TABLE_SIZE		12
139 
140 #define	ZIO_PIPELINE_CONTINUE		0x100
141 #define	ZIO_PIPELINE_STOP		0x101
142 
143 enum zio_flag {
144 	/*
145 	 * Flags inherited by gang, ddt, and vdev children,
146 	 * and that must be equal for two zios to aggregate
147 	 */
148 	ZIO_FLAG_DONT_AGGREGATE	= 1 << 0,
149 	ZIO_FLAG_IO_REPAIR	= 1 << 1,
150 	ZIO_FLAG_SELF_HEAL	= 1 << 2,
151 	ZIO_FLAG_RESILVER	= 1 << 3,
152 	ZIO_FLAG_SCRUB		= 1 << 4,
153 	ZIO_FLAG_SCAN_THREAD	= 1 << 5,
154 
155 #define	ZIO_FLAG_AGG_INHERIT	(ZIO_FLAG_CANFAIL - 1)
156 
157 	/*
158 	 * Flags inherited by ddt, gang, and vdev children.
159 	 */
160 	ZIO_FLAG_CANFAIL	= 1 << 6,	/* must be first for INHERIT */
161 	ZIO_FLAG_SPECULATIVE	= 1 << 7,
162 	ZIO_FLAG_CONFIG_WRITER	= 1 << 8,
163 	ZIO_FLAG_DONT_RETRY	= 1 << 9,
164 	ZIO_FLAG_DONT_CACHE	= 1 << 10,
165 	ZIO_FLAG_NODATA		= 1 << 11,
166 	ZIO_FLAG_INDUCE_DAMAGE	= 1 << 12,
167 
168 #define	ZIO_FLAG_DDT_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
169 #define	ZIO_FLAG_GANG_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
170 
171 	/*
172 	 * Flags inherited by vdev children.
173 	 */
174 	ZIO_FLAG_IO_RETRY	= 1 << 13,	/* must be first for INHERIT */
175 	ZIO_FLAG_PROBE		= 1 << 14,
176 	ZIO_FLAG_TRYHARD	= 1 << 15,
177 	ZIO_FLAG_OPTIONAL	= 1 << 16,
178 
179 #define	ZIO_FLAG_VDEV_INHERIT	(ZIO_FLAG_DONT_QUEUE - 1)
180 
181 	/*
182 	 * Flags not inherited by any children.
183 	 */
184 	ZIO_FLAG_DONT_QUEUE	= 1 << 17,	/* must be first for INHERIT */
185 	ZIO_FLAG_DONT_PROPAGATE	= 1 << 18,
186 	ZIO_FLAG_IO_BYPASS	= 1 << 19,
187 	ZIO_FLAG_IO_REWRITE	= 1 << 20,
188 	ZIO_FLAG_RAW		= 1 << 21,
189 	ZIO_FLAG_GANG_CHILD	= 1 << 22,
190 	ZIO_FLAG_DDT_CHILD	= 1 << 23,
191 	ZIO_FLAG_GODFATHER	= 1 << 24
192 };
193 
194 #define	ZIO_FLAG_MUSTSUCCEED		0
195 
196 #define	ZIO_DDT_CHILD_FLAGS(zio)				\
197 	(((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |		\
198 	ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
199 
200 #define	ZIO_GANG_CHILD_FLAGS(zio)				\
201 	(((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |		\
202 	ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
203 
204 #define	ZIO_VDEV_CHILD_FLAGS(zio)				\
205 	(((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |		\
206 	ZIO_FLAG_CANFAIL)
207 
208 enum zio_child {
209 	ZIO_CHILD_VDEV = 0,
210 	ZIO_CHILD_GANG,
211 	ZIO_CHILD_DDT,
212 	ZIO_CHILD_LOGICAL,
213 	ZIO_CHILD_TYPES
214 };
215 
216 enum zio_wait_type {
217 	ZIO_WAIT_READY = 0,
218 	ZIO_WAIT_DONE,
219 	ZIO_WAIT_TYPES
220 };
221 
222 /*
223  * We'll take the unused errnos, 'EBADE' and 'EBADR' (from the Convergent
224  * graveyard) to indicate checksum errors and fragmentation.
225  */
226 #define	ECKSUM	EBADE
227 #define	EFRAGS	EBADR
228 
229 typedef void zio_done_func_t(zio_t *zio);
230 
231 extern uint8_t zio_priority_table[ZIO_PRIORITY_TABLE_SIZE];
232 extern char *zio_type_name[ZIO_TYPES];
233 
234 /*
235  * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
236  * identifies any block in the pool.  By convention, the meta-objset (MOS)
237  * is objset 0, and the meta-dnode is object 0.  This covers all blocks
238  * except root blocks and ZIL blocks, which are defined as follows:
239  *
240  * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
241  * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
242  * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
243  *
244  * Note: this structure is called a bookmark because its original purpose
245  * was to remember where to resume a pool-wide traverse.
246  *
247  * Note: this structure is passed between userland and the kernel.
248  * Therefore it must not change size or alignment between 32/64 bit
249  * compilation options.
250  */
251 typedef struct zbookmark {
252 	uint64_t	zb_objset;
253 	uint64_t	zb_object;
254 	int64_t		zb_level;
255 	uint64_t	zb_blkid;
256 } zbookmark_t;
257 
258 #define	SET_BOOKMARK(zb, objset, object, level, blkid)  \
259 {                                                       \
260 	(zb)->zb_objset = objset;                       \
261 	(zb)->zb_object = object;                       \
262 	(zb)->zb_level = level;                         \
263 	(zb)->zb_blkid = blkid;                         \
264 }
265 
266 #define	ZB_DESTROYED_OBJSET	(-1ULL)
267 
268 #define	ZB_ROOT_OBJECT		(0ULL)
269 #define	ZB_ROOT_LEVEL		(-1LL)
270 #define	ZB_ROOT_BLKID		(0ULL)
271 
272 #define	ZB_ZIL_OBJECT		(0ULL)
273 #define	ZB_ZIL_LEVEL		(-2LL)
274 
275 typedef struct zio_prop {
276 	enum zio_checksum	zp_checksum;
277 	enum zio_compress	zp_compress;
278 	dmu_object_type_t	zp_type;
279 	uint8_t			zp_level;
280 	uint8_t			zp_copies;
281 	uint8_t			zp_dedup;
282 	uint8_t			zp_dedup_verify;
283 } zio_prop_t;
284 
285 typedef struct zio_cksum_report zio_cksum_report_t;
286 
287 typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
288     const void *good_data);
289 typedef void zio_cksum_free_f(void *cbdata, size_t size);
290 
291 struct zio_bad_cksum;				/* defined in zio_checksum.h */
292 
293 struct zio_cksum_report {
294 	struct zio_cksum_report *zcr_next;
295 	nvlist_t		*zcr_ereport;
296 	nvlist_t		*zcr_detector;
297 	void			*zcr_cbdata;
298 	size_t			zcr_cbinfo;	/* passed to zcr_free() */
299 	uint64_t		zcr_align;
300 	uint64_t		zcr_length;
301 	zio_cksum_finish_f	*zcr_finish;
302 	zio_cksum_free_f	*zcr_free;
303 
304 	/* internal use only */
305 	struct zio_bad_cksum	*zcr_ckinfo;	/* information from failure */
306 };
307 
308 typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,
309     void *arg);
310 
311 zio_vsd_cksum_report_f	zio_vsd_default_cksum_report;
312 
313 typedef struct zio_vsd_ops {
314 	zio_done_func_t		*vsd_free;
315 	zio_vsd_cksum_report_f	*vsd_cksum_report;
316 } zio_vsd_ops_t;
317 
318 typedef struct zio_gang_node {
319 	zio_gbh_phys_t		*gn_gbh;
320 	struct zio_gang_node	*gn_child[SPA_GBH_NBLKPTRS];
321 } zio_gang_node_t;
322 
323 typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
324     zio_gang_node_t *gn, void *data);
325 
326 typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);
327 
328 typedef struct zio_transform {
329 	void			*zt_orig_data;
330 	uint64_t		zt_orig_size;
331 	uint64_t		zt_bufsize;
332 	zio_transform_func_t	*zt_transform;
333 	struct zio_transform	*zt_next;
334 } zio_transform_t;
335 
336 typedef int zio_pipe_stage_t(zio_t *zio);
337 
338 /*
339  * The io_reexecute flags are distinct from io_flags because the child must
340  * be able to propagate them to the parent.  The normal io_flags are local
341  * to the zio, not protected by any lock, and not modifiable by children;
342  * the reexecute flags are protected by io_lock, modifiable by children,
343  * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
344  */
345 #define	ZIO_REEXECUTE_NOW	0x01
346 #define	ZIO_REEXECUTE_SUSPEND	0x02
347 
348 typedef struct zio_link {
349 	zio_t		*zl_parent;
350 	zio_t		*zl_child;
351 	list_node_t	zl_parent_node;
352 	list_node_t	zl_child_node;
353 } zio_link_t;
354 
355 struct zio {
356 	/* Core information about this I/O */
357 	zbookmark_t	io_bookmark;
358 	zio_prop_t	io_prop;
359 	zio_type_t	io_type;
360 	enum zio_child	io_child_type;
361 	int		io_cmd;
362 	uint8_t		io_priority;
363 	uint8_t		io_reexecute;
364 	uint8_t		io_state[ZIO_WAIT_TYPES];
365 	uint64_t	io_txg;
366 	spa_t		*io_spa;
367 	blkptr_t	*io_bp;
368 	blkptr_t	*io_bp_override;
369 	blkptr_t	io_bp_copy;
370 	list_t		io_parent_list;
371 	list_t		io_child_list;
372 	zio_link_t	*io_walk_link;
373 	zio_t		*io_logical;
374 	zio_transform_t *io_transform_stack;
375 
376 	/* Callback info */
377 	zio_done_func_t	*io_ready;
378 	zio_done_func_t	*io_done;
379 	void		*io_private;
380 	int64_t		io_prev_space_delta;	/* DMU private */
381 	blkptr_t	io_bp_orig;
382 
383 	/* Data represented by this I/O */
384 	void		*io_data;
385 	void		*io_orig_data;
386 	uint64_t	io_size;
387 	uint64_t	io_orig_size;
388 
389 	/* Stuff for the vdev stack */
390 	vdev_t		*io_vd;
391 	void		*io_vsd;
392 	const zio_vsd_ops_t *io_vsd_ops;
393 
394 	uint64_t	io_offset;
395 	uint64_t	io_deadline;
396 	avl_node_t	io_offset_node;
397 	avl_node_t	io_deadline_node;
398 	avl_tree_t	*io_vdev_tree;
399 
400 	/* Internal pipeline state */
401 	enum zio_flag	io_flags;
402 	enum zio_stage	io_stage;
403 	enum zio_stage	io_pipeline;
404 	enum zio_flag	io_orig_flags;
405 	enum zio_stage	io_orig_stage;
406 	enum zio_stage	io_orig_pipeline;
407 	int		io_error;
408 	int		io_child_error[ZIO_CHILD_TYPES];
409 	uint64_t	io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];
410 	uint64_t	io_child_count;
411 	uint64_t	io_parent_count;
412 	uint64_t	*io_stall;
413 	zio_t		*io_gang_leader;
414 	zio_gang_node_t	*io_gang_tree;
415 	void		*io_executor;
416 	void		*io_waiter;
417 	kmutex_t	io_lock;
418 	kcondvar_t	io_cv;
419 
420 	/* FMA state */
421 	zio_cksum_report_t *io_cksum_report;
422 	uint64_t	io_ena;
423 
424 	/* Taskq dispatching state */
425 	taskq_ent_t	io_tqent;
426 };
427 
428 extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
429     zio_done_func_t *done, void *private, enum zio_flag flags);
430 
431 extern zio_t *zio_root(spa_t *spa,
432     zio_done_func_t *done, void *private, enum zio_flag flags);
433 
434 extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
435     uint64_t size, zio_done_func_t *done, void *private,
436     int priority, enum zio_flag flags, const zbookmark_t *zb);
437 
438 extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
439     void *data, uint64_t size, const zio_prop_t *zp,
440     zio_done_func_t *ready, zio_done_func_t *done, void *private,
441     int priority, enum zio_flag flags, const zbookmark_t *zb);
442 
443 extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
444     void *data, uint64_t size, zio_done_func_t *done, void *private,
445     int priority, enum zio_flag flags, zbookmark_t *zb);
446 
447 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies);
448 
449 extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
450 
451 extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
452     const blkptr_t *bp,
453     zio_done_func_t *done, void *private, enum zio_flag flags);
454 
455 extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
456     zio_done_func_t *done, void *private, int priority, enum zio_flag flags);
457 
458 extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
459     uint64_t size, void *data, int checksum,
460     zio_done_func_t *done, void *private, int priority, enum zio_flag flags,
461     boolean_t labels);
462 
463 extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
464     uint64_t size, void *data, int checksum,
465     zio_done_func_t *done, void *private, int priority, enum zio_flag flags,
466     boolean_t labels);
467 
468 extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
469     const blkptr_t *bp, enum zio_flag flags);
470 
471 extern int zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp,
472     blkptr_t *old_bp, uint64_t size, boolean_t use_slog);
473 extern void zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp);
474 extern void zio_flush(zio_t *zio, vdev_t *vd);
475 extern void zio_shrink(zio_t *zio, uint64_t size);
476 
477 extern int zio_wait(zio_t *zio);
478 extern void zio_nowait(zio_t *zio);
479 extern void zio_execute(zio_t *zio);
480 extern void zio_interrupt(zio_t *zio);
481 
482 extern zio_t *zio_walk_parents(zio_t *cio);
483 extern zio_t *zio_walk_children(zio_t *pio);
484 extern zio_t *zio_unique_parent(zio_t *cio);
485 extern void zio_add_child(zio_t *pio, zio_t *cio);
486 
487 extern void *zio_buf_alloc(size_t size);
488 extern void zio_buf_free(void *buf, size_t size);
489 extern void *zio_data_buf_alloc(size_t size);
490 extern void zio_data_buf_free(void *buf, size_t size);
491 
492 extern void zio_resubmit_stage_async(void *);
493 
494 extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
495     uint64_t offset, void *data, uint64_t size, int type, int priority,
496     enum zio_flag flags, zio_done_func_t *done, void *private);
497 
498 extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
499     void *data, uint64_t size, int type, int priority,
500     enum zio_flag flags, zio_done_func_t *done, void *private);
501 
502 extern void zio_vdev_io_bypass(zio_t *zio);
503 extern void zio_vdev_io_reissue(zio_t *zio);
504 extern void zio_vdev_io_redone(zio_t *zio);
505 
506 extern void zio_checksum_verified(zio_t *zio);
507 extern int zio_worst_error(int e1, int e2);
508 
509 extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
510     enum zio_checksum parent);
511 extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
512     enum zio_checksum child, enum zio_checksum parent);
513 extern enum zio_compress zio_compress_select(enum zio_compress child,
514     enum zio_compress parent);
515 
516 extern void zio_suspend(spa_t *spa, zio_t *zio);
517 extern int zio_resume(spa_t *spa);
518 extern void zio_resume_wait(spa_t *spa);
519 
520 /*
521  * Initial setup and teardown.
522  */
523 extern void zio_init(void);
524 extern void zio_fini(void);
525 
526 /*
527  * Fault injection
528  */
529 struct zinject_record;
530 extern uint32_t zio_injection_enabled;
531 extern int zio_inject_fault(char *name, int flags, int *id,
532     struct zinject_record *record);
533 extern int zio_inject_list_next(int *id, char *name, size_t buflen,
534     struct zinject_record *record);
535 extern int zio_clear_fault(int id);
536 extern void zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type);
537 extern int zio_handle_fault_injection(zio_t *zio, int error);
538 extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
539 extern int zio_handle_label_injection(zio_t *zio, int error);
540 extern void zio_handle_ignored_writes(zio_t *zio);
541 
542 /*
543  * Checksum ereport functions
544  */
545 extern void zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd, struct zio *zio,
546     uint64_t offset, uint64_t length, void *arg, struct zio_bad_cksum *info);
547 extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
548     const void *good_data, const void *bad_data, boolean_t drop_if_identical);
549 
550 extern void zfs_ereport_send_interim_checksum(zio_cksum_report_t *report);
551 extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
552 
553 /* If we have the good data in hand, this function can be used */
554 extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
555     struct zio *zio, uint64_t offset, uint64_t length,
556     const void *good_data, const void *bad_data, struct zio_bad_cksum *info);
557 
558 /* Called from spa_sync(), but primarily an injection handler */
559 extern void spa_handle_ignored_writes(spa_t *spa);
560 
561 #ifdef	__cplusplus
562 }
563 #endif
564 
565 #endif	/* _ZIO_H */
566