zio.h revision 260742 
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 (c) 2012 by Delphix. All rights reserved.
25 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
26 * Copyright (c) 2013, Joyent, Inc. All rights reserved.
27 * Copyright 2011 Nexenta Systems, Inc.  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
132#define	ZIO_PRIORITY_NOW		(zio_priority_table[0])
133#define	ZIO_PRIORITY_SYNC_READ		(zio_priority_table[1])
134#define	ZIO_PRIORITY_SYNC_WRITE		(zio_priority_table[2])
135#define	ZIO_PRIORITY_LOG_WRITE		(zio_priority_table[3])
136#define	ZIO_PRIORITY_CACHE_FILL		(zio_priority_table[4])
137#define	ZIO_PRIORITY_AGG		(zio_priority_table[5])
138#define	ZIO_PRIORITY_FREE		(zio_priority_table[6])
139#define	ZIO_PRIORITY_ASYNC_WRITE	(zio_priority_table[7])
140#define	ZIO_PRIORITY_ASYNC_READ		(zio_priority_table[8])
141#define	ZIO_PRIORITY_RESILVER		(zio_priority_table[9])
142#define	ZIO_PRIORITY_SCRUB		(zio_priority_table[10])
143#define	ZIO_PRIORITY_DDT_PREFETCH	(zio_priority_table[11])
144#define	ZIO_PRIORITY_TRIM		(zio_priority_table[12])
145#define	ZIO_PRIORITY_TABLE_SIZE		13
146
147#define	ZIO_PIPELINE_CONTINUE		0x100
148#define	ZIO_PIPELINE_STOP		0x101
149
150enum zio_flag {
151	/*
152	 * Flags inherited by gang, ddt, and vdev children,
153	 * and that must be equal for two zios to aggregate
154	 */
155	ZIO_FLAG_DONT_AGGREGATE	= 1 << 0,
156	ZIO_FLAG_IO_REPAIR	= 1 << 1,
157	ZIO_FLAG_SELF_HEAL	= 1 << 2,
158	ZIO_FLAG_RESILVER	= 1 << 3,
159	ZIO_FLAG_SCRUB		= 1 << 4,
160	ZIO_FLAG_SCAN_THREAD	= 1 << 5,
161
162#define	ZIO_FLAG_AGG_INHERIT	(ZIO_FLAG_CANFAIL - 1)
163
164	/*
165	 * Flags inherited by ddt, gang, and vdev children.
166	 */
167	ZIO_FLAG_CANFAIL	= 1 << 6,	/* must be first for INHERIT */
168	ZIO_FLAG_SPECULATIVE	= 1 << 7,
169	ZIO_FLAG_CONFIG_WRITER	= 1 << 8,
170	ZIO_FLAG_DONT_RETRY	= 1 << 9,
171	ZIO_FLAG_DONT_CACHE	= 1 << 10,
172	ZIO_FLAG_NODATA		= 1 << 11,
173	ZIO_FLAG_INDUCE_DAMAGE	= 1 << 12,
174
175#define	ZIO_FLAG_DDT_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
176#define	ZIO_FLAG_GANG_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
177
178	/*
179	 * Flags inherited by vdev children.
180	 */
181	ZIO_FLAG_IO_RETRY	= 1 << 13,	/* must be first for INHERIT */
182	ZIO_FLAG_PROBE		= 1 << 14,
183	ZIO_FLAG_TRYHARD	= 1 << 15,
184	ZIO_FLAG_OPTIONAL	= 1 << 16,
185
186#define	ZIO_FLAG_VDEV_INHERIT	(ZIO_FLAG_DONT_QUEUE - 1)
187
188	/*
189	 * Flags not inherited by any children.
190	 */
191	ZIO_FLAG_DONT_QUEUE	= 1 << 17,	/* must be first for INHERIT */
192	ZIO_FLAG_DONT_PROPAGATE	= 1 << 18,
193	ZIO_FLAG_IO_BYPASS	= 1 << 19,
194	ZIO_FLAG_IO_REWRITE	= 1 << 20,
195	ZIO_FLAG_RAW		= 1 << 21,
196	ZIO_FLAG_GANG_CHILD	= 1 << 22,
197	ZIO_FLAG_DDT_CHILD	= 1 << 23,
198	ZIO_FLAG_GODFATHER	= 1 << 24,
199	ZIO_FLAG_NOPWRITE	= 1 << 25,
200	ZIO_FLAG_REEXECUTED	= 1 << 26,
201};
202
203#define	ZIO_FLAG_MUSTSUCCEED		0
204
205#define	ZIO_DDT_CHILD_FLAGS(zio)				\
206	(((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |		\
207	ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
208
209#define	ZIO_GANG_CHILD_FLAGS(zio)				\
210	(((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |		\
211	ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
212
213#define	ZIO_VDEV_CHILD_FLAGS(zio)				\
214	(((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |		\
215	ZIO_FLAG_CANFAIL)
216
217enum zio_child {
218	ZIO_CHILD_VDEV = 0,
219	ZIO_CHILD_GANG,
220	ZIO_CHILD_DDT,
221	ZIO_CHILD_LOGICAL,
222	ZIO_CHILD_TYPES
223};
224
225enum zio_wait_type {
226	ZIO_WAIT_READY = 0,
227	ZIO_WAIT_DONE,
228	ZIO_WAIT_TYPES
229};
230
231/*
232 * We'll take the number 122 and 123 to indicate checksum errors and
233 * fragmentation. Those doesn't collide with any errno values as they
234 * are greater than ELAST.
235 */
236#define	ECKSUM	122
237#define	EFRAGS	123
238
239typedef void zio_done_func_t(zio_t *zio);
240
241extern uint8_t zio_priority_table[ZIO_PRIORITY_TABLE_SIZE];
242extern char *zio_type_name[ZIO_TYPES];
243
244/*
245 * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
246 * identifies any block in the pool.  By convention, the meta-objset (MOS)
247 * is objset 0, and the meta-dnode is object 0.  This covers all blocks
248 * except root blocks and ZIL blocks, which are defined as follows:
249 *
250 * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
251 * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
252 * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
253 *
254 * Note: this structure is called a bookmark because its original purpose
255 * was to remember where to resume a pool-wide traverse.
256 *
257 * Note: this structure is passed between userland and the kernel.
258 * Therefore it must not change size or alignment between 32/64 bit
259 * compilation options.
260 */
261typedef struct zbookmark {
262	uint64_t	zb_objset;
263	uint64_t	zb_object;
264	int64_t		zb_level;
265	uint64_t	zb_blkid;
266} zbookmark_t;
267
268#define	SET_BOOKMARK(zb, objset, object, level, blkid)  \
269{                                                       \
270	(zb)->zb_objset = objset;                       \
271	(zb)->zb_object = object;                       \
272	(zb)->zb_level = level;                         \
273	(zb)->zb_blkid = blkid;                         \
274}
275
276#define	ZB_DESTROYED_OBJSET	(-1ULL)
277
278#define	ZB_ROOT_OBJECT		(0ULL)
279#define	ZB_ROOT_LEVEL		(-1LL)
280#define	ZB_ROOT_BLKID		(0ULL)
281
282#define	ZB_ZIL_OBJECT		(0ULL)
283#define	ZB_ZIL_LEVEL		(-2LL)
284
285#define	ZB_IS_ZERO(zb)						\
286	((zb)->zb_objset == 0 && (zb)->zb_object == 0 &&	\
287	(zb)->zb_level == 0 && (zb)->zb_blkid == 0)
288#define	ZB_IS_ROOT(zb)				\
289	((zb)->zb_object == ZB_ROOT_OBJECT &&	\
290	(zb)->zb_level == ZB_ROOT_LEVEL &&	\
291	(zb)->zb_blkid == ZB_ROOT_BLKID)
292
293typedef struct zio_prop {
294	enum zio_checksum	zp_checksum;
295	enum zio_compress	zp_compress;
296	dmu_object_type_t	zp_type;
297	uint8_t			zp_level;
298	uint8_t			zp_copies;
299	boolean_t		zp_dedup;
300	boolean_t		zp_dedup_verify;
301	boolean_t		zp_nopwrite;
302} zio_prop_t;
303
304typedef struct zio_cksum_report zio_cksum_report_t;
305
306typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
307    const void *good_data);
308typedef void zio_cksum_free_f(void *cbdata, size_t size);
309
310struct zio_bad_cksum;				/* defined in zio_checksum.h */
311struct dnode_phys;
312
313struct zio_cksum_report {
314	struct zio_cksum_report *zcr_next;
315	nvlist_t		*zcr_ereport;
316	nvlist_t		*zcr_detector;
317	void			*zcr_cbdata;
318	size_t			zcr_cbinfo;	/* passed to zcr_free() */
319	uint64_t		zcr_align;
320	uint64_t		zcr_length;
321	zio_cksum_finish_f	*zcr_finish;
322	zio_cksum_free_f	*zcr_free;
323
324	/* internal use only */
325	struct zio_bad_cksum	*zcr_ckinfo;	/* information from failure */
326};
327
328typedef void zio_vsd_cksum_report_f(zio_t *zio, zio_cksum_report_t *zcr,
329    void *arg);
330
331zio_vsd_cksum_report_f	zio_vsd_default_cksum_report;
332
333typedef struct zio_vsd_ops {
334	zio_done_func_t		*vsd_free;
335	zio_vsd_cksum_report_f	*vsd_cksum_report;
336} zio_vsd_ops_t;
337
338typedef struct zio_gang_node {
339	zio_gbh_phys_t		*gn_gbh;
340	struct zio_gang_node	*gn_child[SPA_GBH_NBLKPTRS];
341} zio_gang_node_t;
342
343typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
344    zio_gang_node_t *gn, void *data);
345
346typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);
347
348typedef struct zio_transform {
349	void			*zt_orig_data;
350	uint64_t		zt_orig_size;
351	uint64_t		zt_bufsize;
352	zio_transform_func_t	*zt_transform;
353	struct zio_transform	*zt_next;
354} zio_transform_t;
355
356typedef int zio_pipe_stage_t(zio_t *zio);
357
358/*
359 * The io_reexecute flags are distinct from io_flags because the child must
360 * be able to propagate them to the parent.  The normal io_flags are local
361 * to the zio, not protected by any lock, and not modifiable by children;
362 * the reexecute flags are protected by io_lock, modifiable by children,
363 * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
364 */
365#define	ZIO_REEXECUTE_NOW	0x01
366#define	ZIO_REEXECUTE_SUSPEND	0x02
367
368typedef struct zio_link {
369	zio_t		*zl_parent;
370	zio_t		*zl_child;
371	list_node_t	zl_parent_node;
372	list_node_t	zl_child_node;
373} zio_link_t;
374
375/*
376 * Used for TRIM kstat.
377 */
378typedef struct zio_trim_stats {
379	/*
380	 * Number of bytes successfully TRIMmed.
381	 */
382	kstat_named_t bytes;
383
384	/*
385	 * Number of successful TRIM requests.
386	 */
387	kstat_named_t success;
388
389	/*
390	 * Number of TRIM requests that failed because TRIM is not
391	 * supported.
392	 */
393	kstat_named_t unsupported;
394
395	/*
396	 * Number of TRIM requests that failed for other reasons.
397	 */
398	kstat_named_t failed;
399} zio_trim_stats_t;
400
401extern zio_trim_stats_t zio_trim_stats;
402
403#define ZIO_TRIM_STAT_INCR(stat, val) \
404	atomic_add_64(&zio_trim_stats.stat.value.ui64, (val));
405#define ZIO_TRIM_STAT_BUMP(stat) \
406	ZIO_TRIM_STAT_INCR(stat, 1);
407
408struct zio {
409	/* Core information about this I/O */
410	zbookmark_t	io_bookmark;
411	zio_prop_t	io_prop;
412	zio_type_t	io_type;
413	enum zio_child	io_child_type;
414	int		io_cmd;
415	uint8_t		io_priority;
416	uint8_t		io_reexecute;
417	uint8_t		io_state[ZIO_WAIT_TYPES];
418	uint64_t	io_txg;
419	spa_t		*io_spa;
420	blkptr_t	*io_bp;
421	blkptr_t	*io_bp_override;
422	blkptr_t	io_bp_copy;
423	list_t		io_parent_list;
424	list_t		io_child_list;
425	zio_link_t	*io_walk_link;
426	zio_t		*io_logical;
427	zio_transform_t *io_transform_stack;
428
429	/* Callback info */
430	zio_done_func_t	*io_ready;
431	zio_done_func_t	*io_done;
432	void		*io_private;
433	int64_t		io_prev_space_delta;	/* DMU private */
434	blkptr_t	io_bp_orig;
435
436	/* Data represented by this I/O */
437	void		*io_data;
438	void		*io_orig_data;
439	uint64_t	io_size;
440	uint64_t	io_orig_size;
441
442	/* Stuff for the vdev stack */
443	vdev_t		*io_vd;
444	void		*io_vsd;
445	const zio_vsd_ops_t *io_vsd_ops;
446
447	uint64_t	io_offset;
448	uint64_t	io_deadline;
449	hrtime_t	io_timestamp;
450	avl_node_t	io_offset_node;
451	avl_node_t	io_deadline_node;
452	avl_tree_t	*io_vdev_tree;
453
454	/* Internal pipeline state */
455	enum zio_flag	io_flags;
456	enum zio_stage	io_stage;
457	enum zio_stage	io_pipeline;
458	enum zio_flag	io_orig_flags;
459	enum zio_stage	io_orig_stage;
460	enum zio_stage	io_orig_pipeline;
461	int		io_error;
462	int		io_child_error[ZIO_CHILD_TYPES];
463	uint64_t	io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];
464	uint64_t	io_child_count;
465	uint64_t	io_parent_count;
466	uint64_t	*io_stall;
467	zio_t		*io_gang_leader;
468	zio_gang_node_t	*io_gang_tree;
469	void		*io_executor;
470	void		*io_waiter;
471	kmutex_t	io_lock;
472	kcondvar_t	io_cv;
473
474	/* FMA state */
475	zio_cksum_report_t *io_cksum_report;
476	uint64_t	io_ena;
477
478	/* Taskq dispatching state */
479	taskq_ent_t	io_tqent;
480
481	avl_node_t	io_trim_node;
482	list_node_t	io_trim_link;
483};
484
485extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
486    zio_done_func_t *done, void *priv, enum zio_flag flags);
487
488extern zio_t *zio_root(spa_t *spa,
489    zio_done_func_t *done, void *priv, enum zio_flag flags);
490
491extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
492    uint64_t size, zio_done_func_t *done, void *priv,
493    int priority, enum zio_flag flags, const zbookmark_t *zb);
494
495extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
496    void *data, uint64_t size, const zio_prop_t *zp,
497    zio_done_func_t *ready, zio_done_func_t *done, void *priv,
498    int priority, enum zio_flag flags, const zbookmark_t *zb);
499
500extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
501    void *data, uint64_t size, zio_done_func_t *done, void *priv,
502    int priority, enum zio_flag flags, zbookmark_t *zb);
503
504extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies,
505    boolean_t nopwrite);
506
507extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
508
509extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
510    const blkptr_t *bp,
511    zio_done_func_t *done, void *priv, enum zio_flag flags);
512
513extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
514    uint64_t offset, uint64_t size, zio_done_func_t *done, void *priv,
515    int priority, enum zio_flag flags);
516
517extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
518    uint64_t size, void *data, int checksum,
519    zio_done_func_t *done, void *priv, int priority, enum zio_flag flags,
520    boolean_t labels);
521
522extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
523    uint64_t size, void *data, int checksum,
524    zio_done_func_t *done, void *priv, int priority, enum zio_flag flags,
525    boolean_t labels);
526
527extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
528    const blkptr_t *bp, uint64_t size, enum zio_flag flags);
529
530extern int zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp,
531    blkptr_t *old_bp, uint64_t size, boolean_t use_slog);
532extern void zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp);
533extern void zio_flush(zio_t *zio, vdev_t *vd);
534extern zio_t *zio_trim(zio_t *zio, spa_t *spa, vdev_t *vd, uint64_t offset,
535    uint64_t size);
536extern void zio_shrink(zio_t *zio, uint64_t size);
537
538extern int zio_wait(zio_t *zio);
539extern void zio_nowait(zio_t *zio);
540extern void zio_execute(zio_t *zio);
541extern void zio_interrupt(zio_t *zio);
542
543extern zio_t *zio_walk_parents(zio_t *cio);
544extern zio_t *zio_walk_children(zio_t *pio);
545extern zio_t *zio_unique_parent(zio_t *cio);
546extern void zio_add_child(zio_t *pio, zio_t *cio);
547
548extern void *zio_buf_alloc(size_t size);
549extern void zio_buf_free(void *buf, size_t size);
550extern void *zio_data_buf_alloc(size_t size);
551extern void zio_data_buf_free(void *buf, size_t size);
552
553extern void zio_resubmit_stage_async(void *);
554
555extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
556    uint64_t offset, void *data, uint64_t size, int type, int priority,
557    enum zio_flag flags, zio_done_func_t *done, void *priv);
558
559extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
560    void *data, uint64_t size, int type, int priority,
561    enum zio_flag flags, zio_done_func_t *done, void *priv);
562
563extern void zio_vdev_io_bypass(zio_t *zio);
564extern void zio_vdev_io_reissue(zio_t *zio);
565extern void zio_vdev_io_redone(zio_t *zio);
566
567extern void zio_checksum_verified(zio_t *zio);
568extern int zio_worst_error(int e1, int e2);
569
570extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
571    enum zio_checksum parent);
572extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
573    enum zio_checksum child, enum zio_checksum parent);
574extern enum zio_compress zio_compress_select(enum zio_compress child,
575    enum zio_compress parent);
576
577extern void zio_suspend(spa_t *spa, zio_t *zio);
578extern int zio_resume(spa_t *spa);
579extern void zio_resume_wait(spa_t *spa);
580
581/*
582 * Initial setup and teardown.
583 */
584extern void zio_init(void);
585extern void zio_fini(void);
586
587/*
588 * Fault injection
589 */
590struct zinject_record;
591extern uint32_t zio_injection_enabled;
592extern int zio_inject_fault(char *name, int flags, int *id,
593    struct zinject_record *record);
594extern int zio_inject_list_next(int *id, char *name, size_t buflen,
595    struct zinject_record *record);
596extern int zio_clear_fault(int id);
597extern void zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type);
598extern int zio_handle_fault_injection(zio_t *zio, int error);
599extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
600extern int zio_handle_label_injection(zio_t *zio, int error);
601extern void zio_handle_ignored_writes(zio_t *zio);
602extern uint64_t zio_handle_io_delay(zio_t *zio);
603
604/*
605 * Checksum ereport functions
606 */
607extern void zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd, struct zio *zio,
608    uint64_t offset, uint64_t length, void *arg, struct zio_bad_cksum *info);
609extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
610    const void *good_data, const void *bad_data, boolean_t drop_if_identical);
611
612extern void zfs_ereport_send_interim_checksum(zio_cksum_report_t *report);
613extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
614
615/* If we have the good data in hand, this function can be used */
616extern void zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
617    struct zio *zio, uint64_t offset, uint64_t length,
618    const void *good_data, const void *bad_data, struct zio_bad_cksum *info);
619
620/* Called from spa_sync(), but primarily an injection handler */
621extern void spa_handle_ignored_writes(spa_t *spa);
622
623/* zbookmark functions */
624boolean_t zbookmark_is_before(const struct dnode_phys *dnp,
625    const zbookmark_t *zb1, const zbookmark_t *zb2);
626
627#ifdef	__cplusplus
628}
629#endif
630
631#endif	/* _ZIO_H */
632