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 */