xref: /freebsd/sys/contrib/openzfs/include/sys/zio.h (revision 87bf66d4a7488c496af110d4d05cc0273d49f82e)
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 https://opensource.org/licenses/CDDL-1.0.
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, 2024 by Delphix. All rights reserved.
26  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
27  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
28  * Copyright 2016 Toomas Soome <tsoome@me.com>
29  * Copyright (c) 2019, Allan Jude
30  * Copyright (c) 2019, 2023, 2024, Klara Inc.
31  * Copyright (c) 2019-2020, Michael Niewöhner
32  * Copyright (c) 2024 by George Melikov. All rights reserved.
33  */
34 
35 #ifndef _ZIO_H
36 #define	_ZIO_H
37 
38 #include <sys/zio_priority.h>
39 #include <sys/zfs_context.h>
40 #include <sys/spa.h>
41 #include <sys/txg.h>
42 #include <sys/avl.h>
43 #include <sys/fs/zfs.h>
44 #include <sys/zio_impl.h>
45 
46 #ifdef	__cplusplus
47 extern "C" {
48 #endif
49 
50 /*
51  * Embedded checksum
52  */
53 #define	ZEC_MAGIC	0x210da7ab10c7a11ULL
54 
55 typedef struct zio_eck {
56 	uint64_t	zec_magic;	/* for validation, endianness	*/
57 	zio_cksum_t	zec_cksum;	/* 256-bit checksum		*/
58 } zio_eck_t;
59 
60 /*
61  * Gang block headers are self-checksumming and contain an array
62  * of block pointers.
63  */
64 #define	SPA_GANGBLOCKSIZE	SPA_MINBLOCKSIZE
65 #define	SPA_GBH_NBLKPTRS	((SPA_GANGBLOCKSIZE - \
66 	sizeof (zio_eck_t)) / sizeof (blkptr_t))
67 #define	SPA_GBH_FILLER		((SPA_GANGBLOCKSIZE - \
68 	sizeof (zio_eck_t) - \
69 	(SPA_GBH_NBLKPTRS * sizeof (blkptr_t))) /\
70 	sizeof (uint64_t))
71 
72 typedef struct zio_gbh {
73 	blkptr_t		zg_blkptr[SPA_GBH_NBLKPTRS];
74 	uint64_t		zg_filler[SPA_GBH_FILLER];
75 	zio_eck_t		zg_tail;
76 } zio_gbh_phys_t;
77 
78 enum zio_checksum {
79 	ZIO_CHECKSUM_INHERIT = 0,
80 	ZIO_CHECKSUM_ON,
81 	ZIO_CHECKSUM_OFF,
82 	ZIO_CHECKSUM_LABEL,
83 	ZIO_CHECKSUM_GANG_HEADER,
84 	ZIO_CHECKSUM_ZILOG,
85 	ZIO_CHECKSUM_FLETCHER_2,
86 	ZIO_CHECKSUM_FLETCHER_4,
87 	ZIO_CHECKSUM_SHA256,
88 	ZIO_CHECKSUM_ZILOG2,
89 	ZIO_CHECKSUM_NOPARITY,
90 	ZIO_CHECKSUM_SHA512,
91 	ZIO_CHECKSUM_SKEIN,
92 	ZIO_CHECKSUM_EDONR,
93 	ZIO_CHECKSUM_BLAKE3,
94 	ZIO_CHECKSUM_FUNCTIONS
95 };
96 
97 /*
98  * The number of "legacy" compression functions which can be set on individual
99  * objects.
100  */
101 #define	ZIO_CHECKSUM_LEGACY_FUNCTIONS ZIO_CHECKSUM_ZILOG2
102 
103 #define	ZIO_CHECKSUM_ON_VALUE	ZIO_CHECKSUM_FLETCHER_4
104 #define	ZIO_CHECKSUM_DEFAULT	ZIO_CHECKSUM_ON
105 
106 #define	ZIO_CHECKSUM_MASK	0xffULL
107 #define	ZIO_CHECKSUM_VERIFY	(1U << 8)
108 
109 #define	ZIO_DEDUPCHECKSUM	ZIO_CHECKSUM_SHA256
110 
111 /* macros defining encryption lengths */
112 #define	ZIO_OBJSET_MAC_LEN		32
113 #define	ZIO_DATA_IV_LEN			12
114 #define	ZIO_DATA_SALT_LEN		8
115 #define	ZIO_DATA_MAC_LEN		16
116 
117 /*
118  * The number of "legacy" compression functions which can be set on individual
119  * objects.
120  */
121 #define	ZIO_COMPRESS_LEGACY_FUNCTIONS ZIO_COMPRESS_LZ4
122 
123 /*
124  * The meaning of "compress = on" selected by the compression features enabled
125  * on a given pool.
126  */
127 #define	ZIO_COMPRESS_LEGACY_ON_VALUE	ZIO_COMPRESS_LZJB
128 #define	ZIO_COMPRESS_LZ4_ON_VALUE	ZIO_COMPRESS_LZ4
129 
130 #define	ZIO_COMPRESS_DEFAULT		ZIO_COMPRESS_ON
131 
132 #define	BOOTFS_COMPRESS_VALID(compress)			\
133 	((compress) == ZIO_COMPRESS_LZJB ||		\
134 	(compress) == ZIO_COMPRESS_LZ4 ||		\
135 	(compress) == ZIO_COMPRESS_GZIP_1 ||		\
136 	(compress) == ZIO_COMPRESS_GZIP_2 ||		\
137 	(compress) == ZIO_COMPRESS_GZIP_3 ||		\
138 	(compress) == ZIO_COMPRESS_GZIP_4 ||		\
139 	(compress) == ZIO_COMPRESS_GZIP_5 ||		\
140 	(compress) == ZIO_COMPRESS_GZIP_6 ||		\
141 	(compress) == ZIO_COMPRESS_GZIP_7 ||		\
142 	(compress) == ZIO_COMPRESS_GZIP_8 ||		\
143 	(compress) == ZIO_COMPRESS_GZIP_9 ||		\
144 	(compress) == ZIO_COMPRESS_ZLE ||		\
145 	(compress) == ZIO_COMPRESS_ZSTD ||		\
146 	(compress) == ZIO_COMPRESS_ON ||		\
147 	(compress) == ZIO_COMPRESS_OFF)
148 
149 
150 #define	ZIO_COMPRESS_ALGO(x)	(x & SPA_COMPRESSMASK)
151 #define	ZIO_COMPRESS_LEVEL(x)	((x & ~SPA_COMPRESSMASK) >> SPA_COMPRESSBITS)
152 #define	ZIO_COMPRESS_RAW(type, level)	(type | ((level) << SPA_COMPRESSBITS))
153 
154 #define	ZIO_COMPLEVEL_ZSTD(level)	\
155 	ZIO_COMPRESS_RAW(ZIO_COMPRESS_ZSTD, level)
156 
157 #define	ZIO_FAILURE_MODE_WAIT		0
158 #define	ZIO_FAILURE_MODE_CONTINUE	1
159 #define	ZIO_FAILURE_MODE_PANIC		2
160 
161 typedef enum zio_suspend_reason {
162 	ZIO_SUSPEND_NONE = 0,
163 	ZIO_SUSPEND_IOERR,
164 	ZIO_SUSPEND_MMP,
165 } zio_suspend_reason_t;
166 
167 /*
168  * This was originally an enum type. However, those are 32-bit and there is no
169  * way to make a 64-bit enum type. Since we ran out of bits for flags, we were
170  * forced to upgrade it to a uint64_t.
171  *
172  * NOTE: PLEASE UPDATE THE BITFIELD STRINGS IN zfs_valstr.c IF YOU ADD ANOTHER
173  * FLAG.
174  */
175 typedef uint64_t zio_flag_t;
176 	/*
177 	 * Flags inherited by gang, ddt, and vdev children,
178 	 * and that must be equal for two zios to aggregate
179 	 */
180 #define	ZIO_FLAG_DONT_AGGREGATE	(1ULL << 0)
181 #define	ZIO_FLAG_IO_REPAIR	(1ULL << 1)
182 #define	ZIO_FLAG_SELF_HEAL	(1ULL << 2)
183 #define	ZIO_FLAG_RESILVER	(1ULL << 3)
184 #define	ZIO_FLAG_SCRUB		(1ULL << 4)
185 #define	ZIO_FLAG_SCAN_THREAD	(1ULL << 5)
186 #define	ZIO_FLAG_PHYSICAL	(1ULL << 6)
187 
188 #define	ZIO_FLAG_AGG_INHERIT	(ZIO_FLAG_CANFAIL - 1)
189 
190 	/*
191 	 * Flags inherited by ddt, gang, and vdev children.
192 	 */
193 #define	ZIO_FLAG_CANFAIL	(1ULL << 7)	/* must be first for INHERIT */
194 #define	ZIO_FLAG_SPECULATIVE	(1ULL << 8)
195 #define	ZIO_FLAG_CONFIG_WRITER	(1ULL << 9)
196 #define	ZIO_FLAG_DONT_RETRY	(1ULL << 10)
197 #define	ZIO_FLAG_NODATA		(1ULL << 12)
198 #define	ZIO_FLAG_INDUCE_DAMAGE	(1ULL << 13)
199 #define	ZIO_FLAG_IO_ALLOCATING	(1ULL << 14)
200 
201 #define	ZIO_FLAG_DDT_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
202 #define	ZIO_FLAG_GANG_INHERIT	(ZIO_FLAG_IO_RETRY - 1)
203 
204 	/*
205 	 * Flags inherited by vdev children.
206 	 */
207 #define	ZIO_FLAG_IO_RETRY	(1ULL << 15)	/* must be first for INHERIT */
208 #define	ZIO_FLAG_PROBE		(1ULL << 16)
209 #define	ZIO_FLAG_TRYHARD	(1ULL << 17)
210 #define	ZIO_FLAG_OPTIONAL	(1ULL << 18)
211 #define	ZIO_FLAG_DIO_READ	(1ULL << 19)
212 #define	ZIO_FLAG_VDEV_INHERIT	(ZIO_FLAG_DONT_QUEUE - 1)
213 
214 	/*
215 	 * Flags not inherited by any children.
216 	 */
217 #define	ZIO_FLAG_DONT_QUEUE	(1ULL << 20)	/* must be first for INHERIT */
218 #define	ZIO_FLAG_DONT_PROPAGATE	(1ULL << 21)
219 #define	ZIO_FLAG_IO_BYPASS	(1ULL << 22)
220 #define	ZIO_FLAG_IO_REWRITE	(1ULL << 23)
221 #define	ZIO_FLAG_RAW_COMPRESS	(1ULL << 24)
222 #define	ZIO_FLAG_RAW_ENCRYPT	(1ULL << 25)
223 #define	ZIO_FLAG_GANG_CHILD	(1ULL << 26)
224 #define	ZIO_FLAG_DDT_CHILD	(1ULL << 27)
225 #define	ZIO_FLAG_GODFATHER	(1ULL << 28)
226 #define	ZIO_FLAG_NOPWRITE	(1ULL << 29)
227 #define	ZIO_FLAG_REEXECUTED	(1ULL << 30)
228 #define	ZIO_FLAG_DELEGATED	(1ULL << 31)
229 #define	ZIO_FLAG_DIO_CHKSUM_ERR	(1ULL << 32)
230 
231 #define	ZIO_ALLOCATOR_NONE	(-1)
232 #define	ZIO_HAS_ALLOCATOR(zio)	((zio)->io_allocator != ZIO_ALLOCATOR_NONE)
233 
234 #define	ZIO_FLAG_MUSTSUCCEED		0
235 #define	ZIO_FLAG_RAW	(ZIO_FLAG_RAW_COMPRESS | ZIO_FLAG_RAW_ENCRYPT)
236 
237 #define	ZIO_DDT_CHILD_FLAGS(zio)				\
238 	(((zio)->io_flags & ZIO_FLAG_DDT_INHERIT) |		\
239 	ZIO_FLAG_DDT_CHILD | ZIO_FLAG_CANFAIL)
240 
241 #define	ZIO_GANG_CHILD_FLAGS(zio)				\
242 	(((zio)->io_flags & ZIO_FLAG_GANG_INHERIT) |		\
243 	ZIO_FLAG_GANG_CHILD | ZIO_FLAG_CANFAIL)
244 
245 #define	ZIO_VDEV_CHILD_FLAGS(zio)				\
246 	(((zio)->io_flags & ZIO_FLAG_VDEV_INHERIT) |		\
247 	ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_CANFAIL)
248 
249 #define	ZIO_CHILD_BIT(x)		(1U << (x))
250 #define	ZIO_CHILD_BIT_IS_SET(val, x)	((val) & (1U << (x)))
251 
252 enum zio_child {
253 	ZIO_CHILD_VDEV = 0,
254 	ZIO_CHILD_GANG,
255 	ZIO_CHILD_DDT,
256 	ZIO_CHILD_LOGICAL,
257 	ZIO_CHILD_TYPES
258 };
259 
260 #define	ZIO_CHILD_VDEV_BIT		ZIO_CHILD_BIT(ZIO_CHILD_VDEV)
261 #define	ZIO_CHILD_GANG_BIT		ZIO_CHILD_BIT(ZIO_CHILD_GANG)
262 #define	ZIO_CHILD_DDT_BIT		ZIO_CHILD_BIT(ZIO_CHILD_DDT)
263 #define	ZIO_CHILD_LOGICAL_BIT		ZIO_CHILD_BIT(ZIO_CHILD_LOGICAL)
264 #define	ZIO_CHILD_ALL_BITS					\
265 	(ZIO_CHILD_VDEV_BIT | ZIO_CHILD_GANG_BIT |		\
266 	ZIO_CHILD_DDT_BIT | ZIO_CHILD_LOGICAL_BIT)
267 
268 enum zio_wait_type {
269 	ZIO_WAIT_READY = 0,
270 	ZIO_WAIT_DONE,
271 	ZIO_WAIT_TYPES
272 };
273 
274 typedef void zio_done_func_t(zio_t *zio);
275 
276 extern int zio_exclude_metadata;
277 extern int zio_dva_throttle_enabled;
278 extern const char *const zio_type_name[ZIO_TYPES];
279 
280 /*
281  * A bookmark is a four-tuple <objset, object, level, blkid> that uniquely
282  * identifies any block in the pool.  By convention, the meta-objset (MOS)
283  * is objset 0, and the meta-dnode is object 0.  This covers all blocks
284  * except root blocks and ZIL blocks, which are defined as follows:
285  *
286  * Root blocks (objset_phys_t) are object 0, level -1:  <objset, 0, -1, 0>.
287  * ZIL blocks are bookmarked <objset, 0, -2, blkid == ZIL sequence number>.
288  * dmu_sync()ed ZIL data blocks are bookmarked <objset, object, -2, blkid>.
289  * dnode visit bookmarks are <objset, object id of dnode, -3, 0>.
290  *
291  * Note: this structure is called a bookmark because its original purpose
292  * was to remember where to resume a pool-wide traverse.
293  *
294  * Note: this structure is passed between userland and the kernel, and is
295  * stored on disk (by virtue of being incorporated into other on-disk
296  * structures, e.g. dsl_scan_phys_t).
297  *
298  * If the head_errlog feature is enabled a different on-disk format for error
299  * logs is used. This introduces the use of an error bookmark, a four-tuple
300  * <object, level, blkid, birth> that uniquely identifies any error block
301  * in the pool. The birth transaction group is used to track whether the block
302  * has been overwritten by newer data or added to a snapshot since its marking
303  * as an error.
304  */
305 struct zbookmark_phys {
306 	uint64_t	zb_objset;
307 	uint64_t	zb_object;
308 	int64_t		zb_level;
309 	uint64_t	zb_blkid;
310 };
311 
312 struct zbookmark_err_phys {
313 	uint64_t	zb_object;
314 	int64_t		zb_level;
315 	uint64_t	zb_blkid;
316 	uint64_t	zb_birth;
317 };
318 
319 #define	SET_BOOKMARK(zb, objset, object, level, blkid)  \
320 {                                                       \
321 	(zb)->zb_objset = objset;                       \
322 	(zb)->zb_object = object;                       \
323 	(zb)->zb_level = level;                         \
324 	(zb)->zb_blkid = blkid;                         \
325 }
326 
327 #define	ZB_DESTROYED_OBJSET	(-1ULL)
328 
329 #define	ZB_ROOT_OBJECT		(0ULL)
330 #define	ZB_ROOT_LEVEL		(-1LL)
331 #define	ZB_ROOT_BLKID		(0ULL)
332 
333 #define	ZB_ZIL_OBJECT		(0ULL)
334 #define	ZB_ZIL_LEVEL		(-2LL)
335 
336 #define	ZB_DNODE_LEVEL		(-3LL)
337 #define	ZB_DNODE_BLKID		(0ULL)
338 
339 #define	ZB_IS_ZERO(zb)						\
340 	((zb)->zb_objset == 0 && (zb)->zb_object == 0 &&	\
341 	(zb)->zb_level == 0 && (zb)->zb_blkid == 0)
342 #define	ZB_IS_ROOT(zb)				\
343 	((zb)->zb_object == ZB_ROOT_OBJECT &&	\
344 	(zb)->zb_level == ZB_ROOT_LEVEL &&	\
345 	(zb)->zb_blkid == ZB_ROOT_BLKID)
346 
347 typedef struct zio_prop {
348 	enum zio_checksum	zp_checksum;
349 	enum zio_compress	zp_compress;
350 	uint8_t			zp_complevel;
351 	uint8_t			zp_level;
352 	uint8_t			zp_copies;
353 	dmu_object_type_t	zp_type;
354 	boolean_t		zp_dedup;
355 	boolean_t		zp_dedup_verify;
356 	boolean_t		zp_nopwrite;
357 	boolean_t		zp_brtwrite;
358 	boolean_t		zp_encrypt;
359 	boolean_t		zp_byteorder;
360 	boolean_t		zp_direct_write;
361 	uint8_t			zp_salt[ZIO_DATA_SALT_LEN];
362 	uint8_t			zp_iv[ZIO_DATA_IV_LEN];
363 	uint8_t			zp_mac[ZIO_DATA_MAC_LEN];
364 	uint32_t		zp_zpl_smallblk;
365 	dmu_object_type_t	zp_storage_type;
366 } zio_prop_t;
367 
368 typedef struct zio_cksum_report zio_cksum_report_t;
369 
370 typedef void zio_cksum_finish_f(zio_cksum_report_t *rep,
371     const abd_t *good_data);
372 typedef void zio_cksum_free_f(void *cbdata, size_t size);
373 
374 struct zio_bad_cksum;				/* defined in zio_checksum.h */
375 struct dnode_phys;
376 struct abd;
377 
378 struct zio_cksum_report {
379 	struct zio_cksum_report *zcr_next;
380 	nvlist_t		*zcr_ereport;
381 	nvlist_t		*zcr_detector;
382 	void			*zcr_cbdata;
383 	size_t			zcr_cbinfo;	/* passed to zcr_free() */
384 	uint64_t		zcr_sector;
385 	uint64_t		zcr_align;
386 	uint64_t		zcr_length;
387 	zio_cksum_finish_f	*zcr_finish;
388 	zio_cksum_free_f	*zcr_free;
389 
390 	/* internal use only */
391 	struct zio_bad_cksum	*zcr_ckinfo;	/* information from failure */
392 };
393 
394 typedef struct zio_vsd_ops {
395 	zio_done_func_t		*vsd_free;
396 } zio_vsd_ops_t;
397 
398 typedef struct zio_gang_node {
399 	zio_gbh_phys_t		*gn_gbh;
400 	struct zio_gang_node	*gn_child[SPA_GBH_NBLKPTRS];
401 } zio_gang_node_t;
402 
403 typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
404     zio_gang_node_t *gn, struct abd *data, uint64_t offset);
405 
406 typedef void zio_transform_func_t(zio_t *zio, struct abd *data, uint64_t size);
407 
408 typedef struct zio_transform {
409 	struct abd		*zt_orig_abd;
410 	uint64_t		zt_orig_size;
411 	uint64_t		zt_bufsize;
412 	zio_transform_func_t	*zt_transform;
413 	struct zio_transform	*zt_next;
414 } zio_transform_t;
415 
416 typedef zio_t *zio_pipe_stage_t(zio_t *zio);
417 
418 /*
419  * The io_reexecute flags are distinct from io_flags because the child must
420  * be able to propagate them to the parent.  The normal io_flags are local
421  * to the zio, not protected by any lock, and not modifiable by children;
422  * the reexecute flags are protected by io_lock, modifiable by children,
423  * and always propagated -- even when ZIO_FLAG_DONT_PROPAGATE is set.
424  */
425 #define	ZIO_REEXECUTE_NOW	0x01
426 #define	ZIO_REEXECUTE_SUSPEND	0x02
427 
428 /*
429  * The io_trim flags are used to specify the type of TRIM to perform.  They
430  * only apply to ZIO_TYPE_TRIM zios are distinct from io_flags.
431  */
432 enum trim_flag {
433 	ZIO_TRIM_SECURE		= 1U << 0,
434 };
435 
436 typedef struct zio_alloc_list {
437 	list_t  zal_list;
438 	uint64_t zal_size;
439 } zio_alloc_list_t;
440 
441 typedef struct zio_link {
442 	zio_t		*zl_parent;
443 	zio_t		*zl_child;
444 	list_node_t	zl_parent_node;
445 	list_node_t	zl_child_node;
446 } zio_link_t;
447 
448 enum zio_qstate {
449 	ZIO_QS_NONE = 0,
450 	ZIO_QS_QUEUED,
451 	ZIO_QS_ACTIVE,
452 };
453 
454 struct zio {
455 	/* Core information about this I/O */
456 	zbookmark_phys_t	io_bookmark;
457 	zio_prop_t	io_prop;
458 	zio_type_t	io_type;
459 	enum zio_child	io_child_type;
460 	enum trim_flag	io_trim_flags;
461 	zio_priority_t	io_priority;
462 	uint8_t		io_reexecute;
463 	uint8_t		io_state[ZIO_WAIT_TYPES];
464 	uint64_t	io_txg;
465 	spa_t		*io_spa;
466 	blkptr_t	*io_bp;
467 	blkptr_t	*io_bp_override;
468 	blkptr_t	io_bp_copy;
469 	list_t		io_parent_list;
470 	list_t		io_child_list;
471 	zio_t		*io_logical;
472 	zio_transform_t *io_transform_stack;
473 
474 	/* Callback info */
475 	zio_done_func_t	*io_ready;
476 	zio_done_func_t	*io_children_ready;
477 	zio_done_func_t	*io_done;
478 	void		*io_private;
479 	int64_t		io_prev_space_delta;	/* DMU private */
480 	blkptr_t	io_bp_orig;
481 	/* io_lsize != io_orig_size iff this is a raw write */
482 	uint64_t	io_lsize;
483 
484 	/* Data represented by this I/O */
485 	struct abd	*io_abd;
486 	struct abd	*io_orig_abd;
487 	uint64_t	io_size;
488 	uint64_t	io_orig_size;
489 
490 	/* Stuff for the vdev stack */
491 	vdev_t		*io_vd;
492 	void		*io_vsd;
493 	const zio_vsd_ops_t *io_vsd_ops;
494 	metaslab_class_t *io_metaslab_class;	/* dva throttle class */
495 
496 	enum zio_qstate	io_queue_state;	/* vdev queue state */
497 	union {
498 		list_node_t l;
499 		avl_node_t a;
500 	} io_queue_node ____cacheline_aligned;	/* allocator and vdev queues */
501 	avl_node_t	io_offset_node;	/* vdev offset queues */
502 	uint64_t	io_offset;
503 	hrtime_t	io_timestamp;	/* submitted at */
504 	hrtime_t	io_queued_timestamp;
505 	hrtime_t	io_target_timestamp;
506 	hrtime_t	io_delta;	/* vdev queue service delta */
507 	hrtime_t	io_delay;	/* Device access time (disk or */
508 					/* file). */
509 	zio_alloc_list_t 	io_alloc_list;
510 
511 	/* Internal pipeline state */
512 	zio_flag_t	io_flags;
513 	enum zio_stage	io_stage;
514 	enum zio_stage	io_pipeline;
515 	zio_flag_t	io_orig_flags;
516 	enum zio_stage	io_orig_stage;
517 	enum zio_stage	io_orig_pipeline;
518 	enum zio_stage	io_pipeline_trace;
519 	int		io_error;
520 	int		io_child_error[ZIO_CHILD_TYPES];
521 	uint64_t	io_children[ZIO_CHILD_TYPES][ZIO_WAIT_TYPES];
522 	uint64_t	*io_stall;
523 	zio_t		*io_gang_leader;
524 	zio_gang_node_t	*io_gang_tree;
525 	void		*io_executor;
526 	void		*io_waiter;
527 	void		*io_bio;
528 	kmutex_t	io_lock;
529 	kcondvar_t	io_cv;
530 	int		io_allocator;
531 
532 	/* FMA state */
533 	zio_cksum_report_t *io_cksum_report;
534 	uint64_t	io_ena;
535 
536 	/* Taskq dispatching state */
537 	taskq_ent_t	io_tqent;
538 };
539 
540 enum blk_verify_flag {
541 	BLK_VERIFY_ONLY,
542 	BLK_VERIFY_LOG,
543 	BLK_VERIFY_HALT
544 };
545 
546 enum blk_config_flag {
547 	BLK_CONFIG_HELD,   // SCL_VDEV held for writer
548 	BLK_CONFIG_NEEDED, // SCL_VDEV should be obtained for reader
549 	BLK_CONFIG_SKIP,   // skip checks which require SCL_VDEV
550 };
551 
552 extern int zio_bookmark_compare(const void *, const void *);
553 
554 extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
555     zio_done_func_t *done, void *priv, zio_flag_t flags);
556 
557 extern zio_t *zio_root(spa_t *spa,
558     zio_done_func_t *done, void *priv, zio_flag_t flags);
559 
560 extern void zio_destroy(zio_t *zio);
561 
562 extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
563     struct abd *data, uint64_t lsize, zio_done_func_t *done, void *priv,
564     zio_priority_t priority, zio_flag_t flags, const zbookmark_phys_t *zb);
565 
566 extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
567     struct abd *data, uint64_t size, uint64_t psize, const zio_prop_t *zp,
568     zio_done_func_t *ready, zio_done_func_t *children_ready,
569     zio_done_func_t *done, void *priv, zio_priority_t priority,
570     zio_flag_t flags, const zbookmark_phys_t *zb);
571 
572 extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
573     struct abd *data, uint64_t size, zio_done_func_t *done, void *priv,
574     zio_priority_t priority, zio_flag_t flags, zbookmark_phys_t *zb);
575 
576 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies,
577     boolean_t nopwrite, boolean_t brtwrite);
578 
579 extern void zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp);
580 
581 extern zio_t *zio_claim(zio_t *pio, spa_t *spa, uint64_t txg,
582     const blkptr_t *bp,
583     zio_done_func_t *done, void *priv, zio_flag_t flags);
584 
585 extern zio_t *zio_trim(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
586     zio_done_func_t *done, void *priv, zio_priority_t priority,
587     zio_flag_t flags, enum trim_flag trim_flags);
588 
589 extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
590     uint64_t size, struct abd *data, int checksum,
591     zio_done_func_t *done, void *priv, zio_priority_t priority,
592     zio_flag_t flags, boolean_t labels);
593 
594 extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
595     uint64_t size, struct abd *data, int checksum,
596     zio_done_func_t *done, void *priv, zio_priority_t priority,
597     zio_flag_t flags, boolean_t labels);
598 
599 extern zio_t *zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg,
600     const blkptr_t *bp, zio_flag_t flags);
601 
602 extern int zio_alloc_zil(spa_t *spa, objset_t *os, uint64_t txg,
603     blkptr_t *new_bp, uint64_t size, boolean_t *slog);
604 extern void zio_flush(zio_t *zio, vdev_t *vd);
605 extern void zio_shrink(zio_t *zio, uint64_t size);
606 
607 extern size_t zio_get_compression_max_size(enum zio_compress compress,
608     uint64_t gcd_alloc, uint64_t min_alloc, size_t s_len);
609 extern int zio_wait(zio_t *zio);
610 extern void zio_nowait(zio_t *zio);
611 extern void zio_execute(void *zio);
612 extern void zio_interrupt(void *zio);
613 extern void zio_delay_init(zio_t *zio);
614 extern void zio_delay_interrupt(zio_t *zio);
615 extern void zio_deadman(zio_t *zio, const char *tag);
616 
617 extern zio_t *zio_walk_parents(zio_t *cio, zio_link_t **);
618 extern zio_t *zio_walk_children(zio_t *pio, zio_link_t **);
619 extern zio_t *zio_unique_parent(zio_t *cio);
620 extern void zio_add_child(zio_t *pio, zio_t *cio);
621 extern void zio_add_child_first(zio_t *pio, zio_t *cio);
622 
623 extern void *zio_buf_alloc(size_t size);
624 extern void zio_buf_free(void *buf, size_t size);
625 extern void *zio_data_buf_alloc(size_t size);
626 extern void zio_data_buf_free(void *buf, size_t size);
627 
628 extern void zio_push_transform(zio_t *zio, struct abd *abd, uint64_t size,
629     uint64_t bufsize, zio_transform_func_t *transform);
630 extern void zio_pop_transforms(zio_t *zio);
631 
632 extern void zio_resubmit_stage_async(void *);
633 
634 extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
635     uint64_t offset, struct abd *data, uint64_t size, int type,
636     zio_priority_t priority, zio_flag_t flags,
637     zio_done_func_t *done, void *priv);
638 
639 extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
640     struct abd *data, uint64_t size, zio_type_t type, zio_priority_t priority,
641     zio_flag_t flags, zio_done_func_t *done, void *priv);
642 
643 extern void zio_vdev_io_bypass(zio_t *zio);
644 extern void zio_vdev_io_reissue(zio_t *zio);
645 extern void zio_vdev_io_redone(zio_t *zio);
646 
647 extern void zio_change_priority(zio_t *pio, zio_priority_t priority);
648 
649 extern void zio_checksum_verified(zio_t *zio);
650 extern void zio_dio_chksum_verify_error_report(zio_t *zio);
651 extern int zio_worst_error(int e1, int e2);
652 
653 extern enum zio_checksum zio_checksum_select(enum zio_checksum child,
654     enum zio_checksum parent);
655 extern enum zio_checksum zio_checksum_dedup_select(spa_t *spa,
656     enum zio_checksum child, enum zio_checksum parent);
657 extern enum zio_compress zio_compress_select(spa_t *spa,
658     enum zio_compress child, enum zio_compress parent);
659 extern uint8_t zio_complevel_select(spa_t *spa, enum zio_compress compress,
660     uint8_t child, uint8_t parent);
661 
662 extern void zio_suspend(spa_t *spa, zio_t *zio, zio_suspend_reason_t);
663 extern int zio_resume(spa_t *spa);
664 extern void zio_resume_wait(spa_t *spa);
665 
666 extern boolean_t zfs_blkptr_verify(spa_t *spa, const blkptr_t *bp,
667     enum blk_config_flag blk_config, enum blk_verify_flag blk_verify);
668 
669 /*
670  * Initial setup and teardown.
671  */
672 extern void zio_init(void);
673 extern void zio_fini(void);
674 
675 /*
676  * Fault injection
677  */
678 struct zinject_record;
679 extern uint32_t zio_injection_enabled;
680 extern int zio_inject_fault(char *name, int flags, int *id,
681     struct zinject_record *record);
682 extern int zio_inject_list_next(int *id, char *name, size_t buflen,
683     struct zinject_record *record);
684 extern int zio_clear_fault(int id);
685 extern void zio_handle_panic_injection(spa_t *spa, const char *tag,
686     uint64_t type);
687 extern int zio_handle_decrypt_injection(spa_t *spa, const zbookmark_phys_t *zb,
688     uint64_t type, int error);
689 extern int zio_handle_fault_injection(zio_t *zio, int error);
690 extern int zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error);
691 extern int zio_handle_device_injections(vdev_t *vd, zio_t *zio, int err1,
692     int err2);
693 extern int zio_handle_label_injection(zio_t *zio, int error);
694 extern void zio_handle_ignored_writes(zio_t *zio);
695 extern hrtime_t zio_handle_io_delay(zio_t *zio);
696 extern void zio_handle_import_delay(spa_t *spa, hrtime_t elapsed);
697 extern void zio_handle_export_delay(spa_t *spa, hrtime_t elapsed);
698 
699 /*
700  * Checksum ereport functions
701  */
702 extern int zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd,
703     const zbookmark_phys_t *zb, struct zio *zio, uint64_t offset,
704     uint64_t length, struct zio_bad_cksum *info);
705 extern void zfs_ereport_finish_checksum(zio_cksum_report_t *report,
706     const abd_t *good_data, const abd_t *bad_data, boolean_t drop_if_identical);
707 
708 extern void zfs_ereport_free_checksum(zio_cksum_report_t *report);
709 
710 /* If we have the good data in hand, this function can be used */
711 extern int zfs_ereport_post_checksum(spa_t *spa, vdev_t *vd,
712     const zbookmark_phys_t *zb, struct zio *zio, uint64_t offset,
713     uint64_t length, const abd_t *good_data, const abd_t *bad_data,
714     struct zio_bad_cksum *info);
715 
716 void zio_vsd_default_cksum_report(zio_t *zio, zio_cksum_report_t *zcr);
717 extern void zfs_ereport_snapshot_post(const char *subclass, spa_t *spa,
718     const char *name);
719 
720 /* Called from spa_sync(), but primarily an injection handler */
721 extern void spa_handle_ignored_writes(spa_t *spa);
722 
723 /* zbookmark_phys functions */
724 boolean_t zbookmark_subtree_completed(const struct dnode_phys *dnp,
725     const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block);
726 boolean_t zbookmark_subtree_tbd(const struct dnode_phys *dnp,
727     const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block);
728 int zbookmark_compare(uint16_t dbss1, uint8_t ibs1, uint16_t dbss2,
729     uint8_t ibs2, const zbookmark_phys_t *zb1, const zbookmark_phys_t *zb2);
730 
731 #ifdef	__cplusplus
732 }
733 #endif
734 
735 #endif	/* _ZIO_H */
736