zio.h revision 260763 
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 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
25 * Copyright (c) 2012 by Delphix. All rights reserved.
26 * Copyright (c) 2013 by Delphix. All rights reserved.
27 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
28 */
29
30#ifndef _ZIO_H
31#define	_ZIO_H
32
33#include <sys/zfs_context.h>
34#include <sys/spa.h>
35#include <sys/txg.h>
36#include <sys/avl.h>
37#include <sys/kstat.h>
38#include <sys/fs/zfs.h>
39#include <sys/zio_impl.h>
40
41#ifdef	__cplusplus
42extern "C" {
43#endif
44
45/*
46 * Embedded checksum
47 */
48#define	ZEC_MAGIC	0x210da7ab10c7a11ULL
49
50typedef struct zio_eck {
51	uint64_t	zec_magic;	/* for validation, endianness	*/
52	zio_cksum_t	zec_cksum;	/* 256-bit checksum		*/
53} zio_eck_t;
54
55/*
56 * Gang block headers are self-checksumming and contain an array
57 * of block pointers.
58 */
59#define	SPA_GANGBLOCKSIZE	SPA_MINBLOCKSIZE
60#define	SPA_GBH_NBLKPTRS	((SPA_GANGBLOCKSIZE - \
61	sizeof (zio_eck_t)) / sizeof (blkptr_t))
62#define	SPA_GBH_FILLER		((SPA_GANGBLOCKSIZE - \
63	sizeof (zio_eck_t) - \
64	(SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
65	sizeof (uint64_t))
66
67typedef struct zio_gbh {
68	blkptr_t		zg_blkptr[SPA_GBH_NBLKPTRS];
69	uint64_t		zg_filler[SPA_GBH_FILLER];
70	zio_eck_t		zg_tail;
71} zio_gbh_phys_t;
72
73enum zio_checksum {
74	ZIO_CHECKSUM_INHERIT = 0,
75	ZIO_CHECKSUM_ON,
76	ZIO_CHECKSUM_OFF,
77	ZIO_CHECKSUM_LABEL,
78	ZIO_CHECKSUM_GANG_HEADER,
79	ZIO_CHECKSUM_ZILOG,
80	ZIO_CHECKSUM_FLETCHER_2,
81	ZIO_CHECKSUM_FLETCHER_4,
82	ZIO_CHECKSUM_SHA256,
83	ZIO_CHECKSUM_ZILOG2,
84	ZIO_CHECKSUM_NOPARITY,
85	ZIO_CHECKSUM_FUNCTIONS
86};
87
88#define	ZIO_CHECKSUM_ON_VALUE	ZIO_CHECKSUM_FLETCHER_4
89#define	ZIO_CHECKSUM_DEFAULT	ZIO_CHECKSUM_ON
90
91#define	ZIO_CHECKSUM_MASK	0xffULL
92#define	ZIO_CHECKSUM_VERIFY	(1 << 8)
93
94#define	ZIO_DEDUPCHECKSUM	ZIO_CHECKSUM_SHA256
95#define	ZIO_DEDUPDITTO_MIN	100
96
97enum zio_compress {
98	ZIO_COMPRESS_INHERIT = 0,
99	ZIO_COMPRESS_ON,
100	ZIO_COMPRESS_OFF,
101	ZIO_COMPRESS_LZJB,
102	ZIO_COMPRESS_EMPTY,
103	ZIO_COMPRESS_GZIP_1,
104	ZIO_COMPRESS_GZIP_2,
105	ZIO_COMPRESS_GZIP_3,
106	ZIO_COMPRESS_GZIP_4,
107	ZIO_COMPRESS_GZIP_5,
108	ZIO_COMPRESS_GZIP_6,
109	ZIO_COMPRESS_GZIP_7,
110	ZIO_COMPRESS_GZIP_8,
111	ZIO_COMPRESS_GZIP_9,
112	ZIO_COMPRESS_ZLE,
113	ZIO_COMPRESS_LZ4,
114	ZIO_COMPRESS_FUNCTIONS
115};
116
117/* N.B. when altering this value, also change BOOTFS_COMPRESS_VALID below */
118#define	ZIO_COMPRESS_ON_VALUE	ZIO_COMPRESS_LZJB
119#define	ZIO_COMPRESS_DEFAULT	ZIO_COMPRESS_OFF
120
121#define	BOOTFS_COMPRESS_VALID(compress)			\
122	((compress) == ZIO_COMPRESS_LZJB ||		\
123	(compress) == ZIO_COMPRESS_LZ4 ||		\
124	((compress) == ZIO_COMPRESS_ON &&		\
125	ZIO_COMPRESS_ON_VALUE == ZIO_COMPRESS_LZJB) ||	\
126	(compress) == ZIO_COMPRESS_OFF)
127
128#define	ZIO_FAILURE_MODE_WAIT		0
129#define	ZIO_FAILURE_MODE_CONTINUE	1
130#define	ZIO_FAILURE_MODE_PANIC		2
131
132typedef enum zio_priority {
133	ZIO_PRIORITY_SYNC_READ,
134	ZIO_PRIORITY_SYNC_WRITE,	/* ZIL */
135	ZIO_PRIORITY_ASYNC_READ,	/* prefetch */
136	ZIO_PRIORITY_ASYNC_WRITE,	/* spa_sync() */
137	ZIO_PRIORITY_SCRUB,		/* asynchronous scrub/resilver reads */
138	ZIO_PRIORITY_NUM_QUEUEABLE,
139
140	ZIO_PRIORITY_NOW		/* non-queued i/os (e.g. free) */
141} zio_priority_t;
142
143#define	ZIO_PIPELINE_CONTINUE		0x100
144#define	ZIO_PIPELINE_STOP		0x101
145
146enum zio_flag {
147	/*
148	 * Flags inherited by gang, ddt, and vdev children,
149	 * and that must be equal for two zios to aggregate
150	 */
151	ZIO_FLAG_DONT_AGGREGATE	= 1 << 0,
152	ZIO_FLAG_IO_REPAIR	= 1 << 1,
153	ZIO_FLAG_SELF_HEAL	= 1 << 2,
154	ZIO_FLAG_RESILVER	= 1 << 3,
155	ZIO_FLAG_SCRUB		= 1 << 4,
156	ZIO_FLAG_SCAN_THREAD	= 1 << 5,
157
158#define	ZIO_FLAG_AGG_INHERIT	(ZIO_FLAG_CANFAIL - 1)
159
160	/*
161	 * Flags inherited by ddt, gang, and vdev children.
162	 */
163	ZIO_FLAG_CANFAIL	= 1 << 6,	/* must be first for INHERIT */
164	ZIO_FLAG_SPECULATIVE	= 1 << 7,
165	ZIO_FLAG_CONFIG_WRITER	= 1 << 8,
166	ZIO_FLAG_DONT_RETRY	= 1 << 9,
167	ZIO_FLAG_DONT_CACHE	= 1 << 10,
168	ZIO_FLAG_NODATA		= 1 << 11,
169	ZIO_FLAG_INDUCE_DAMAGE	= 1 << 12,
170
171#define	ZIO_FLAG_DDT_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
172#define	ZIO_FLAG_GANG_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
173
174	/*
175	 * Flags inherited by vdev children.
176	 */
177	ZIO_FLAG_IO_RETRY	= 1 << 13,	/* must be first for INHERIT */
178	ZIO_FLAG_PROBE		= 1 << 14,
179	ZIO_FLAG_TRYHARD	= 1 << 15,
180	ZIO_FLAG_OPTIONAL	= 1 << 16,
181
182#define	ZIO_FLAG_VDEV_INHERIT	(ZIO_FLAG_DONT_QUEUE - 1)
183
184	/*
185	 * Flags not inherited by any children.
186	 */
187	ZIO_FLAG_DONT_QUEUE	= 1 << 17,	/* must be first for INHERIT */
188	ZIO_FLAG_DONT_PROPAGATE	= 1 << 18,
189	ZIO_FLAG_IO_BYPASS	= 1 << 19,
190	ZIO_FLAG_IO_REWRITE	= 1 << 20,
191	ZIO_FLAG_RAW		= 1 << 21,
192	ZIO_FLAG_GANG_CHILD	= 1 << 22,
193	ZIO_FLAG_DDT_CHILD	= 1 << 23,
194	ZIO_FLAG_GODFATHER	= 1 << 24,
195	ZIO_FLAG_NOPWRITE	= 1 << 25,
196	ZIO_FLAG_REEXECUTED	= 1 << 26,
197	ZIO_FLAG_DELEGATED	= 1 << 27,
198};
199
200#define	ZIO_FLAG_MUSTSUCCEED		0
201
202#define	ZIO_DDT_CHILD_FLAGS(zio)				\
203	(((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |		\
204	ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
205
206#define	ZIO_GANG_CHILD_FLAGS(zio)				\
207	(((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |		\
208	ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
209
210#define	ZIO_VDEV_CHILD_FLAGS(zio)				\
211	(((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |		\
212	ZIO_FLAG_CANFAIL)
213
214enum zio_child {
215	ZIO_CHILD_VDEV = 0,
216	ZIO_CHILD_GANG,
217	ZIO_CHILD_DDT,
218	ZIO_CHILD_LOGICAL,
219	ZIO_CHILD_TYPES
220};
221
222enum zio_wait_type {
223	ZIO_WAIT_READY = 0,
224	ZIO_WAIT_DONE,
225	ZIO_WAIT_TYPES
226};
227
228/*
229 * We'll take the number 122 and 123 to indicate checksum errors and
230 * fragmentation. Those doesn't collide with any errno values as they
231 * are greater than ELAST.
232 */
233#define	ECKSUM	122
234#define	EFRAGS	123
235
236typedef void zio_done_func_t(zio_t *zio);
237
238extern const char *zio_type_name[ZIO_TYPES];
239
240/*
241 * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
242 * identifies any block in the pool.  By convention, the meta-objset (MOS)
243 * is objset 0, and the meta-dnode is object 0.  This covers all blocks
244 * except root blocks and ZIL blocks, which are defined as follows:
245 *
246 * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
247 * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
248 * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
249 *
250 * Note: this structure is called a bookmark because its original purpose
251 * was to remember where to resume a pool-wide traverse.
252 *
253 * Note: this structure is passed between userland and the kernel.
254 * Therefore it must not change size or alignment between 32/64 bit
255 * compilation options.
256 */
257typedef struct zbookmark {
258	uint64_t	zb_objset;
259	uint64_t	zb_object;
260	int64_t		zb_level;
261	uint64_t	zb_blkid;
262} zbookmark_t;
263
264#define	SET_BOOKMARK(zb, objset, object, level, blkid)  \
265{                                                       \
266	(zb)->zb_objset = objset;                       \
267	(zb)->zb_object = object;                       \
268	(zb)->zb_level = level;                         \
269	(zb)->zb_blkid = blkid;                         \
270}
271
272#define	ZB_DESTROYED_OBJSET	(-1ULL)
273
274#define	ZB_ROOT_OBJECT		(0ULL)
275#define	ZB_ROOT_LEVEL		(-1LL)
276#define	ZB_ROOT_BLKID		(0ULL)
277
278#define	ZB_ZIL_OBJECT		(0ULL)
279#define	ZB_ZIL_LEVEL		(-2LL)
280
281#define	ZB_IS_ZERO(zb)						\
282	((zb)->zb_objset == 0 && (zb)->zb_object == 0 &&	\
283	(zb)->zb_level == 0 && (zb)->zb_blkid == 0)
284#define	ZB_IS_ROOT(zb)				\
285	((zb)->zb_object == ZB_ROOT_OBJECT &&	\
286	(zb)->zb_level == ZB_ROOT_LEVEL &&	\
287	(zb)->zb_blkid == ZB_ROOT_BLKID)
288
289typedef struct zio_prop {
290	enum zio_checksum	zp_checksum;
291	enum zio_compress	zp_compress;
292	dmu_object_type_t	zp_type;
293	uint8_t			zp_level;
294	uint8_t			zp_copies;
295	boolean_t		zp_dedup;
296	boolean_t		zp_dedup_verify;
297	boolean_t		zp_nopwrite;
298} zio_prop_t;
299
300typedef struct zio_cksum_report zio_cksum_report_t;
301
302typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
303    const void *good_data);
304typedef void zio_cksum_free_f(void *cbdata, size_t size);
305
306struct zio_bad_cksum;				/* defined in zio_checksum.h */
307struct dnode_phys;
308
309struct zio_cksum_report {
310	struct zio_cksum_report *zcr_next;
311	nvlist_t		*zcr_ereport;
312	nvlist_t		*zcr_detector;
313	void			*zcr_cbdata;
314	size_t			zcr_cbinfo;	/* passed to zcr_free() */
315	uint64_t		zcr_align;
316	uint64_t		zcr_length;
317	zio_cksum_finish_f	*zcr_finish;
318	zio_cksum_free_f	*zcr_free;
319
320	/* internal use only */
321	struct zio_bad_cksum	*zcr_ckinfo;	/* information from failure */
322};
323
324typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,
325    void *arg);
326
327zio_vsd_cksum_report_f	zio_vsd_default_cksum_report;
328
329typedef struct zio_vsd_ops {
330	zio_done_func_t		*vsd_free;
331	zio_vsd_cksum_report_f	*vsd_cksum_report;
332} zio_vsd_ops_t;
333
334typedef struct zio_gang_node {
335	zio_gbh_phys_t		*gn_gbh;
336	struct zio_gang_node	*gn_child[SPA_GBH_NBLKPTRS];
337} zio_gang_node_t;
338
339typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
340    zio_gang_node_t *gn, void *data);
341
342typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);
343
344typedef struct zio_transform {
345	void			*zt_orig_data;
346	uint64_t		zt_orig_size;
347	uint64_t		zt_bufsize;
348	zio_transform_func_t	*zt_transform;
349	struct zio_transform	*zt_next;
350} zio_transform_t;
351
352typedef int zio_pipe_stage_t(zio_t *zio);
353
354/*
355 * The io_reexecute flags are distinct from io_flags because the child must
356 * be able to propagate them to the parent.  The normal io_flags are local
357 * to the zio, not protected by any lock, and not modifiable by children;
358 * the reexecute flags are protected by io_lock, modifiable by children,
359 * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
360 */
361#define	ZIO_REEXECUTE_NOW	0x01
362#define	ZIO_REEXECUTE_SUSPEND	0x02
363
364typedef struct zio_link {
365	zio_t		*zl_parent;
366	zio_t		*zl_child;
367	list_node_t	zl_parent_node;
368	list_node_t	zl_child_node;
369} zio_link_t;
370
371/*
372 * Used for TRIM kstat.
373 */
374typedef struct zio_trim_stats {
375	/*
376	 * Number of bytes successfully TRIMmed.
377	 */
378	kstat_named_t bytes;
379
380	/*
381	 * Number of successful TRIM requests.
382	 */
383	kstat_named_t success;
384
385	/*
386	 * Number of TRIM requests that failed because TRIM is not
387	 * supported.
388	 */
389	kstat_named_t unsupported;
390
391	/*
392	 * Number of TRIM requests that failed for other reasons.
393	 */
394	kstat_named_t failed;
395} zio_trim_stats_t;
396
397extern zio_trim_stats_t zio_trim_stats;
398
399#define ZIO_TRIM_STAT_INCR(stat, val) \
400	atomic_add_64(&zio_trim_stats.stat.value.ui64, (val));
401#define ZIO_TRIM_STAT_BUMP(stat) \
402	ZIO_TRIM_STAT_INCR(stat, 1);
403
404struct zio {
405	/* Core information about this I/O */
406	zbookmark_t	io_bookmark;
407	zio_prop_t	io_prop;
408	zio_type_t	io_type;
409	enum zio_child	io_child_type;
410	int		io_cmd;
411	zio_priority_t	io_priority;
412	uint8_t		io_reexecute;
413	uint8_t		io_state[ZIO_WAIT_TYPES];
414	uint64_t	io_txg;
415	spa_t		*io_spa;
416	blkptr_t	*io_bp;
417	blkptr_t	*io_bp_override;
418	blkptr_t	io_bp_copy;
419	list_t		io_parent_list;
420	list_t		io_child_list;
421	zio_link_t	*io_walk_link;
422	zio_t		*io_logical;
423	zio_transform_t *io_transform_stack;
424
425	/* Callback info */
426	zio_done_func_t	*io_ready;
427	zio_done_func_t	*io_physdone;
428	zio_done_func_t	*io_done;
429	void		*io_private;
430	int64_t		io_prev_space_delta;	/* DMU private */
431	blkptr_t	io_bp_orig;
432
433	/* Data represented by this I/O */
434	void		*io_data;
435	void		*io_orig_data;
436	uint64_t	io_size;
437	uint64_t	io_orig_size;
438
439	/* Stuff for the vdev stack */
440	vdev_t		*io_vd;
441	void		*io_vsd;
442	const zio_vsd_ops_t *io_vsd_ops;
443
444	uint64_t	io_offset;
445	hrtime_t	io_timestamp;
446	avl_node_t	io_queue_node;
447
448	/* Internal pipeline state */
449	enum zio_flag	io_flags;
450	enum zio_stage	io_stage;
451	enum zio_stage	io_pipeline;
452	enum zio_flag	io_orig_flags;
453	enum zio_stage	io_orig_stage;
454	enum zio_stage	io_orig_pipeline;
455	int		io_error;
456	int		io_child_error[ZIO_CHILD_TYPES];
457	uint64_t	io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];
458	uint64_t	io_child_count;
459	uint64_t	io_phys_children;
460	uint64_t	io_parent_count;
461	uint64_t	*io_stall;
462	zio_t		*io_gang_leader;
463	zio_gang_node_t	*io_gang_tree;
464	void		*io_executor;
465	void		*io_waiter;
466	kmutex_t	io_lock;
467	kcondvar_t	io_cv;
468
469	/* FMA state */
470	zio_cksum_report_t *io_cksum_report;
471	uint64_t	io_ena;
472
473	/* Taskq dispatching state */
474	taskq_ent_t	io_tqent;
475
476	avl_node_t	io_trim_node;
477	list_node_t	io_trim_link;
478};
479
480extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
481    zio_done_func_t *done, void *priv, enum zio_flag flags);
482
483extern zio_t *zio_root(spa_t *spa,
484    zio_done_func_t *done, void *priv, enum zio_flag flags);
485
486extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
487    uint64_t size, zio_done_func_t *done, void *priv,
488    zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb);
489
490extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
491    void *data, uint64_t size, const zio_prop_t *zp,
492    zio_done_func_t *ready, zio_done_func_t *physdone, zio_done_func_t *done,
493    void *priv,
494    zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb);
495
496extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
497    void *data, uint64_t size, zio_done_func_t *done, void *priv,
498    zio_priority_t priority, enum zio_flag flags, zbookmark_t *zb);
499
500extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies,
501    boolean_t nopwrite);
502
503extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
504
505extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
506    const blkptr_t *bp,
507    zio_done_func_t *done, void *priv, enum zio_flag flags);
508
509extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
510    uint64_t offset, uint64_t size, zio_done_func_t *done, void *priv,
511    enum zio_flag flags);
512
513extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
514    uint64_t size, void *data, int checksum,
515    zio_done_func_t *done, void *priv, zio_priority_t priority,
516    enum zio_flag flags, boolean_t labels);
517
518extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
519    uint64_t size, void *data, int checksum,
520    zio_done_func_t *done, void *priv, zio_priority_t priority,
521    enum zio_flag flags, boolean_t labels);
522
523extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
524    const blkptr_t *bp, uint64_t size, enum zio_flag flags);
525
526extern int zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp,
527    blkptr_t *old_bp, uint64_t size, boolean_t use_slog);
528extern void zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp);
529extern void zio_flush(zio_t *zio, vdev_t *vd);
530extern zio_t *zio_trim(zio_t *zio, spa_t *spa, vdev_t *vd, uint64_t offset,
531    uint64_t size);
532extern void zio_shrink(zio_t *zio, uint64_t size);
533
534extern int zio_wait(zio_t *zio);
535extern void zio_nowait(zio_t *zio);
536extern void zio_execute(zio_t *zio);
537extern void zio_interrupt(zio_t *zio);
538
539extern zio_t *zio_walk_parents(zio_t *cio);
540extern zio_t *zio_walk_children(zio_t *pio);
541extern zio_t *zio_unique_parent(zio_t *cio);
542extern void zio_add_child(zio_t *pio, zio_t *cio);
543
544extern void *zio_buf_alloc(size_t size);
545extern void zio_buf_free(void *buf, size_t size);
546extern void *zio_data_buf_alloc(size_t size);
547extern void zio_data_buf_free(void *buf, size_t size);
548
549extern void zio_resubmit_stage_async(void *);
550
551extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
552    uint64_t offset, void *data, uint64_t size, int type,
553    zio_priority_t priority, enum zio_flag flags,
554    zio_done_func_t *done, void *priv);
555
556extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
557    void *data, uint64_t size, int type, zio_priority_t priority,
558    enum zio_flag flags, zio_done_func_t *done, void *priv);
559
560extern void zio_vdev_io_bypass(zio_t *zio);
561extern void zio_vdev_io_reissue(zio_t *zio);
562extern void zio_vdev_io_redone(zio_t *zio);
563
564extern void zio_checksum_verified(zio_t *zio);
565extern int zio_worst_error(int e1, int e2);
566
567extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
568    enum zio_checksum parent);
569extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
570    enum zio_checksum child, enum zio_checksum parent);
571extern enum zio_compress zio_compress_select(enum zio_compress child,
572    enum zio_compress parent);
573
574extern void zio_suspend(spa_t *spa, zio_t *zio);
575extern int zio_resume(spa_t *spa);
576extern void zio_resume_wait(spa_t *spa);
577
578/*
579 * Initial setup and teardown.
580 */
581extern void zio_init(void);
582extern void zio_fini(void);
583
584/*
585 * Fault injection
586 */
587struct zinject_record;
588extern uint32_t zio_injection_enabled;
589extern int zio_inject_fault(char *name, int flags, int *id,
590    struct zinject_record *record);
591extern int zio_inject_list_next(int *id, char *name, size_t buflen,
592    struct zinject_record *record);
593extern int zio_clear_fault(int id);
594extern void zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type);
595extern int zio_handle_fault_injection(zio_t *zio, int error);
596extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
597extern int zio_handle_label_injection(zio_t *zio, int error);
598extern void zio_handle_ignored_writes(zio_t *zio);
599extern uint64_t zio_handle_io_delay(zio_t *zio);
600
601/*
602 * Checksum ereport functions
603 */
604extern void zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd, struct zio *zio,
605    uint64_t offset, uint64_t length, void *arg, struct zio_bad_cksum *info);
606extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
607    const void *good_data, const void *bad_data, boolean_t drop_if_identical);
608
609extern void zfs_ereport_send_interim_checksum(zio_cksum_report_t *report);
610extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
611
612/* If we have the good data in hand, this function can be used */
613extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
614    struct zio *zio, uint64_t offset, uint64_t length,
615    const void *good_data, const void *bad_data, struct zio_bad_cksum *info);
616
617/* Called from spa_sync(), but primarily an injection handler */
618extern void spa_handle_ignored_writes(spa_t *spa);
619
620/* zbookmark functions */
621boolean_t zbookmark_is_before(const struct dnode_phys *dnp,
622    const zbookmark_t *zb1, const zbookmark_t *zb2);
623
624#ifdef	__cplusplus
625}
626#endif
627
628#endif	/* _ZIO_H */
629