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.
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.
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]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2011, 2017 by Delphix. All rights reserved.
24 * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
25 * Copyright (c) 2014 Integros [integros.com]
28 #include <sys/sysmacros.h>
29 #include <sys/zfs_context.h>
30 #include <sys/fm/fs/zfs.h>
33 #include <sys/spa_impl.h>
34 #include <sys/vdev_impl.h>
35 #include <sys/zio_impl.h>
36 #include <sys/zio_compress.h>
37 #include <sys/zio_checksum.h>
38 #include <sys/dmu_objset.h>
41 #include <sys/blkptr.h>
42 #include <sys/zfeature.h>
43 #include <sys/metaslab_impl.h>
47 * ==========================================================================
48 * I/O type descriptions
49 * ==========================================================================
51 const char *zio_type_name
[ZIO_TYPES
] = {
52 "zio_null", "zio_read", "zio_write", "zio_free", "zio_claim",
56 boolean_t zio_dva_throttle_enabled
= B_TRUE
;
59 * ==========================================================================
61 * ==========================================================================
63 kmem_cache_t
*zio_cache
;
64 kmem_cache_t
*zio_link_cache
;
65 kmem_cache_t
*zio_buf_cache
[SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
];
66 kmem_cache_t
*zio_data_buf_cache
[SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
];
69 extern vmem_t
*zio_alloc_arena
;
72 #define ZIO_PIPELINE_CONTINUE 0x100
73 #define ZIO_PIPELINE_STOP 0x101
75 #define BP_SPANB(indblkshift, level) \
76 (((uint64_t)1) << ((level) * ((indblkshift) - SPA_BLKPTRSHIFT)))
77 #define COMPARE_META_LEVEL 0x80000000ul
79 * The following actions directly effect the spa's sync-to-convergence logic.
80 * The values below define the sync pass when we start performing the action.
81 * Care should be taken when changing these values as they directly impact
82 * spa_sync() performance. Tuning these values may introduce subtle performance
83 * pathologies and should only be done in the context of performance analysis.
84 * These tunables will eventually be removed and replaced with #defines once
85 * enough analysis has been done to determine optimal values.
87 * The 'zfs_sync_pass_deferred_free' pass must be greater than 1 to ensure that
88 * regular blocks are not deferred.
90 int zfs_sync_pass_deferred_free
= 2; /* defer frees starting in this pass */
91 int zfs_sync_pass_dont_compress
= 5; /* don't compress starting in this pass */
92 int zfs_sync_pass_rewrite
= 2; /* rewrite new bps starting in this pass */
95 * An allocating zio is one that either currently has the DVA allocate
96 * stage set or will have it later in its lifetime.
98 #define IO_IS_ALLOCATING(zio) ((zio)->io_orig_pipeline & ZIO_STAGE_DVA_ALLOCATE)
100 boolean_t zio_requeue_io_start_cut_in_line
= B_TRUE
;
103 int zio_buf_debug_limit
= 16384;
105 int zio_buf_debug_limit
= 0;
108 static void zio_taskq_dispatch(zio_t
*, zio_taskq_type_t
, boolean_t
);
114 vmem_t
*data_alloc_arena
= NULL
;
117 data_alloc_arena
= zio_alloc_arena
;
119 zio_cache
= kmem_cache_create("zio_cache",
120 sizeof (zio_t
), 0, NULL
, NULL
, NULL
, NULL
, NULL
, 0);
121 zio_link_cache
= kmem_cache_create("zio_link_cache",
122 sizeof (zio_link_t
), 0, NULL
, NULL
, NULL
, NULL
, NULL
, 0);
125 * For small buffers, we want a cache for each multiple of
126 * SPA_MINBLOCKSIZE. For larger buffers, we want a cache
127 * for each quarter-power of 2.
129 for (c
= 0; c
< SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
; c
++) {
130 size_t size
= (c
+ 1) << SPA_MINBLOCKSHIFT
;
133 size_t cflags
= (size
> zio_buf_debug_limit
) ? KMC_NODEBUG
: 0;
140 * If we are using watchpoints, put each buffer on its own page,
141 * to eliminate the performance overhead of trapping to the
142 * kernel when modifying a non-watched buffer that shares the
143 * page with a watched buffer.
145 if (arc_watch
&& !IS_P2ALIGNED(size
, PAGESIZE
))
148 if (size
<= 4 * SPA_MINBLOCKSIZE
) {
149 align
= SPA_MINBLOCKSIZE
;
150 } else if (IS_P2ALIGNED(size
, p2
>> 2)) {
151 align
= MIN(p2
>> 2, PAGESIZE
);
156 (void) sprintf(name
, "zio_buf_%lu", (ulong_t
)size
);
157 zio_buf_cache
[c
] = kmem_cache_create(name
, size
,
158 align
, NULL
, NULL
, NULL
, NULL
, NULL
, cflags
);
161 * Since zio_data bufs do not appear in crash dumps, we
162 * pass KMC_NOTOUCH so that no allocator metadata is
163 * stored with the buffers.
165 (void) sprintf(name
, "zio_data_buf_%lu", (ulong_t
)size
);
166 zio_data_buf_cache
[c
] = kmem_cache_create(name
, size
,
167 align
, NULL
, NULL
, NULL
, NULL
, data_alloc_arena
,
168 cflags
| KMC_NOTOUCH
);
173 ASSERT(zio_buf_cache
[c
] != NULL
);
174 if (zio_buf_cache
[c
- 1] == NULL
)
175 zio_buf_cache
[c
- 1] = zio_buf_cache
[c
];
177 ASSERT(zio_data_buf_cache
[c
] != NULL
);
178 if (zio_data_buf_cache
[c
- 1] == NULL
)
179 zio_data_buf_cache
[c
- 1] = zio_data_buf_cache
[c
];
189 kmem_cache_t
*last_cache
= NULL
;
190 kmem_cache_t
*last_data_cache
= NULL
;
192 for (c
= 0; c
< SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
; c
++) {
193 if (zio_buf_cache
[c
] != last_cache
) {
194 last_cache
= zio_buf_cache
[c
];
195 kmem_cache_destroy(zio_buf_cache
[c
]);
197 zio_buf_cache
[c
] = NULL
;
199 if (zio_data_buf_cache
[c
] != last_data_cache
) {
200 last_data_cache
= zio_data_buf_cache
[c
];
201 kmem_cache_destroy(zio_data_buf_cache
[c
]);
203 zio_data_buf_cache
[c
] = NULL
;
206 kmem_cache_destroy(zio_link_cache
);
207 kmem_cache_destroy(zio_cache
);
213 * ==========================================================================
214 * Allocate and free I/O buffers
215 * ==========================================================================
219 * Use zio_buf_alloc to allocate ZFS metadata. This data will appear in a
220 * crashdump if the kernel panics, so use it judiciously. Obviously, it's
221 * useful to inspect ZFS metadata, but if possible, we should avoid keeping
222 * excess / transient data in-core during a crashdump.
225 zio_buf_alloc(size_t size
)
227 size_t c
= (size
- 1) >> SPA_MINBLOCKSHIFT
;
229 VERIFY3U(c
, <, SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
);
231 return (kmem_cache_alloc(zio_buf_cache
[c
], KM_PUSHPAGE
));
235 * Use zio_data_buf_alloc to allocate data. The data will not appear in a
236 * crashdump if the kernel panics. This exists so that we will limit the amount
237 * of ZFS data that shows up in a kernel crashdump. (Thus reducing the amount
238 * of kernel heap dumped to disk when the kernel panics)
241 zio_data_buf_alloc(size_t size
)
243 size_t c
= (size
- 1) >> SPA_MINBLOCKSHIFT
;
245 VERIFY3U(c
, <, SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
);
247 return (kmem_cache_alloc(zio_data_buf_cache
[c
], KM_PUSHPAGE
));
251 zio_buf_free(void *buf
, size_t size
)
253 size_t c
= (size
- 1) >> SPA_MINBLOCKSHIFT
;
255 VERIFY3U(c
, <, SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
);
257 kmem_cache_free(zio_buf_cache
[c
], buf
);
261 zio_data_buf_free(void *buf
, size_t size
)
263 size_t c
= (size
- 1) >> SPA_MINBLOCKSHIFT
;
265 VERIFY3U(c
, <, SPA_MAXBLOCKSIZE
>> SPA_MINBLOCKSHIFT
);
267 kmem_cache_free(zio_data_buf_cache
[c
], buf
);
271 * ==========================================================================
272 * Push and pop I/O transform buffers
273 * ==========================================================================
276 zio_push_transform(zio_t
*zio
, abd_t
*data
, uint64_t size
, uint64_t bufsize
,
277 zio_transform_func_t
*transform
)
279 zio_transform_t
*zt
= kmem_alloc(sizeof (zio_transform_t
), KM_SLEEP
);
282 * Ensure that anyone expecting this zio to contain a linear ABD isn't
283 * going to get a nasty surprise when they try to access the data.
285 IMPLY(abd_is_linear(zio
->io_abd
), abd_is_linear(data
));
287 zt
->zt_orig_abd
= zio
->io_abd
;
288 zt
->zt_orig_size
= zio
->io_size
;
289 zt
->zt_bufsize
= bufsize
;
290 zt
->zt_transform
= transform
;
292 zt
->zt_next
= zio
->io_transform_stack
;
293 zio
->io_transform_stack
= zt
;
300 zio_pop_transforms(zio_t
*zio
)
304 while ((zt
= zio
->io_transform_stack
) != NULL
) {
305 if (zt
->zt_transform
!= NULL
)
306 zt
->zt_transform(zio
,
307 zt
->zt_orig_abd
, zt
->zt_orig_size
);
309 if (zt
->zt_bufsize
!= 0)
310 abd_free(zio
->io_abd
);
312 zio
->io_abd
= zt
->zt_orig_abd
;
313 zio
->io_size
= zt
->zt_orig_size
;
314 zio
->io_transform_stack
= zt
->zt_next
;
316 kmem_free(zt
, sizeof (zio_transform_t
));
321 * ==========================================================================
322 * I/O transform callbacks for subblocks and decompression
323 * ==========================================================================
326 zio_subblock(zio_t
*zio
, abd_t
*data
, uint64_t size
)
328 ASSERT(zio
->io_size
> size
);
330 if (zio
->io_type
== ZIO_TYPE_READ
)
331 abd_copy(data
, zio
->io_abd
, size
);
335 zio_decompress(zio_t
*zio
, abd_t
*data
, uint64_t size
)
337 if (zio
->io_error
== 0) {
338 void *tmp
= abd_borrow_buf(data
, size
);
339 int ret
= zio_decompress_data(BP_GET_COMPRESS(zio
->io_bp
),
340 zio
->io_abd
, tmp
, zio
->io_size
, size
);
341 abd_return_buf_copy(data
, tmp
, size
);
344 zio
->io_error
= SET_ERROR(EIO
);
349 * ==========================================================================
350 * I/O parent/child relationships and pipeline interlocks
351 * ==========================================================================
354 zio_walk_parents(zio_t
*cio
, zio_link_t
**zl
)
356 list_t
*pl
= &cio
->io_parent_list
;
358 *zl
= (*zl
== NULL
) ? list_head(pl
) : list_next(pl
, *zl
);
362 ASSERT((*zl
)->zl_child
== cio
);
363 return ((*zl
)->zl_parent
);
367 zio_walk_children(zio_t
*pio
, zio_link_t
**zl
)
369 list_t
*cl
= &pio
->io_child_list
;
371 *zl
= (*zl
== NULL
) ? list_head(cl
) : list_next(cl
, *zl
);
375 ASSERT((*zl
)->zl_parent
== pio
);
376 return ((*zl
)->zl_child
);
380 zio_unique_parent(zio_t
*cio
)
382 zio_link_t
*zl
= NULL
;
383 zio_t
*pio
= zio_walk_parents(cio
, &zl
);
385 VERIFY3P(zio_walk_parents(cio
, &zl
), ==, NULL
);
390 zio_add_child(zio_t
*pio
, zio_t
*cio
)
392 zio_link_t
*zl
= kmem_cache_alloc(zio_link_cache
, KM_SLEEP
);
395 * Logical I/Os can have logical, gang, or vdev children.
396 * Gang I/Os can have gang or vdev children.
397 * Vdev I/Os can only have vdev children.
398 * The following ASSERT captures all of these constraints.
400 ASSERT3S(cio
->io_child_type
, <=, pio
->io_child_type
);
405 mutex_enter(&cio
->io_lock
);
406 mutex_enter(&pio
->io_lock
);
408 ASSERT(pio
->io_state
[ZIO_WAIT_DONE
] == 0);
410 for (int w
= 0; w
< ZIO_WAIT_TYPES
; w
++)
411 pio
->io_children
[cio
->io_child_type
][w
] += !cio
->io_state
[w
];
413 list_insert_head(&pio
->io_child_list
, zl
);
414 list_insert_head(&cio
->io_parent_list
, zl
);
416 pio
->io_child_count
++;
417 cio
->io_parent_count
++;
419 mutex_exit(&pio
->io_lock
);
420 mutex_exit(&cio
->io_lock
);
424 zio_remove_child(zio_t
*pio
, zio_t
*cio
, zio_link_t
*zl
)
426 ASSERT(zl
->zl_parent
== pio
);
427 ASSERT(zl
->zl_child
== cio
);
429 mutex_enter(&cio
->io_lock
);
430 mutex_enter(&pio
->io_lock
);
432 list_remove(&pio
->io_child_list
, zl
);
433 list_remove(&cio
->io_parent_list
, zl
);
435 pio
->io_child_count
--;
436 cio
->io_parent_count
--;
438 mutex_exit(&pio
->io_lock
);
439 mutex_exit(&cio
->io_lock
);
441 kmem_cache_free(zio_link_cache
, zl
);
445 zio_wait_for_children(zio_t
*zio
, uint8_t childbits
, enum zio_wait_type wait
)
447 boolean_t waiting
= B_FALSE
;
449 mutex_enter(&zio
->io_lock
);
450 ASSERT(zio
->io_stall
== NULL
);
451 for (int c
= 0; c
< ZIO_CHILD_TYPES
; c
++) {
452 if (!(ZIO_CHILD_BIT_IS_SET(childbits
, c
)))
455 uint64_t *countp
= &zio
->io_children
[c
][wait
];
458 ASSERT3U(zio
->io_stage
, !=, ZIO_STAGE_OPEN
);
459 zio
->io_stall
= countp
;
464 mutex_exit(&zio
->io_lock
);
469 zio_notify_parent(zio_t
*pio
, zio_t
*zio
, enum zio_wait_type wait
)
471 uint64_t *countp
= &pio
->io_children
[zio
->io_child_type
][wait
];
472 int *errorp
= &pio
->io_child_error
[zio
->io_child_type
];
474 mutex_enter(&pio
->io_lock
);
475 if (zio
->io_error
&& !(zio
->io_flags
& ZIO_FLAG_DONT_PROPAGATE
))
476 *errorp
= zio_worst_error(*errorp
, zio
->io_error
);
477 pio
->io_reexecute
|= zio
->io_reexecute
;
478 ASSERT3U(*countp
, >, 0);
482 if (*countp
== 0 && pio
->io_stall
== countp
) {
483 zio_taskq_type_t type
=
484 pio
->io_stage
< ZIO_STAGE_VDEV_IO_START
? ZIO_TASKQ_ISSUE
:
486 pio
->io_stall
= NULL
;
487 mutex_exit(&pio
->io_lock
);
489 * Dispatch the parent zio in its own taskq so that
490 * the child can continue to make progress. This also
491 * prevents overflowing the stack when we have deeply nested
492 * parent-child relationships.
494 zio_taskq_dispatch(pio
, type
, B_FALSE
);
496 mutex_exit(&pio
->io_lock
);
501 zio_inherit_child_errors(zio_t
*zio
, enum zio_child c
)
503 if (zio
->io_child_error
[c
] != 0 && zio
->io_error
== 0)
504 zio
->io_error
= zio
->io_child_error
[c
];
508 zio_bookmark_compare(const void *x1
, const void *x2
)
510 const zio_t
*z1
= x1
;
511 const zio_t
*z2
= x2
;
513 if (z1
->io_bookmark
.zb_objset
< z2
->io_bookmark
.zb_objset
)
515 if (z1
->io_bookmark
.zb_objset
> z2
->io_bookmark
.zb_objset
)
518 if (z1
->io_bookmark
.zb_object
< z2
->io_bookmark
.zb_object
)
520 if (z1
->io_bookmark
.zb_object
> z2
->io_bookmark
.zb_object
)
523 if (z1
->io_bookmark
.zb_level
< z2
->io_bookmark
.zb_level
)
525 if (z1
->io_bookmark
.zb_level
> z2
->io_bookmark
.zb_level
)
528 if (z1
->io_bookmark
.zb_blkid
< z2
->io_bookmark
.zb_blkid
)
530 if (z1
->io_bookmark
.zb_blkid
> z2
->io_bookmark
.zb_blkid
)
542 * ==========================================================================
543 * Create the various types of I/O (read, write, free, etc)
544 * ==========================================================================
547 zio_create(zio_t
*pio
, spa_t
*spa
, uint64_t txg
, const blkptr_t
*bp
,
548 abd_t
*data
, uint64_t lsize
, uint64_t psize
, zio_done_func_t
*done
,
549 void *private, zio_type_t type
, zio_priority_t priority
,
550 enum zio_flag flags
, vdev_t
*vd
, uint64_t offset
,
551 const zbookmark_phys_t
*zb
, enum zio_stage stage
, enum zio_stage pipeline
)
555 ASSERT3U(psize
, <=, SPA_MAXBLOCKSIZE
);
556 ASSERT(P2PHASE(psize
, SPA_MINBLOCKSIZE
) == 0);
557 ASSERT(P2PHASE(offset
, SPA_MINBLOCKSIZE
) == 0);
559 ASSERT(!vd
|| spa_config_held(spa
, SCL_STATE_ALL
, RW_READER
));
560 ASSERT(!bp
|| !(flags
& ZIO_FLAG_CONFIG_WRITER
));
561 ASSERT(vd
|| stage
== ZIO_STAGE_OPEN
);
563 IMPLY(lsize
!= psize
, (flags
& ZIO_FLAG_RAW
) != 0);
565 zio
= kmem_cache_alloc(zio_cache
, KM_SLEEP
);
566 bzero(zio
, sizeof (zio_t
));
568 mutex_init(&zio
->io_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
569 cv_init(&zio
->io_cv
, NULL
, CV_DEFAULT
, NULL
);
571 list_create(&zio
->io_parent_list
, sizeof (zio_link_t
),
572 offsetof(zio_link_t
, zl_parent_node
));
573 list_create(&zio
->io_child_list
, sizeof (zio_link_t
),
574 offsetof(zio_link_t
, zl_child_node
));
575 metaslab_trace_init(&zio
->io_alloc_list
);
578 zio
->io_child_type
= ZIO_CHILD_VDEV
;
579 else if (flags
& ZIO_FLAG_GANG_CHILD
)
580 zio
->io_child_type
= ZIO_CHILD_GANG
;
581 else if (flags
& ZIO_FLAG_DDT_CHILD
)
582 zio
->io_child_type
= ZIO_CHILD_DDT
;
584 zio
->io_child_type
= ZIO_CHILD_LOGICAL
;
587 zio
->io_bp
= (blkptr_t
*)bp
;
588 zio
->io_bp_copy
= *bp
;
589 zio
->io_bp_orig
= *bp
;
590 if (type
!= ZIO_TYPE_WRITE
||
591 zio
->io_child_type
== ZIO_CHILD_DDT
)
592 zio
->io_bp
= &zio
->io_bp_copy
; /* so caller can free */
593 if (zio
->io_child_type
== ZIO_CHILD_LOGICAL
)
594 zio
->io_logical
= zio
;
595 if (zio
->io_child_type
> ZIO_CHILD_GANG
&& BP_IS_GANG(bp
))
596 pipeline
|= ZIO_GANG_STAGES
;
602 zio
->io_private
= private;
604 zio
->io_priority
= priority
;
606 zio
->io_offset
= offset
;
607 zio
->io_orig_abd
= zio
->io_abd
= data
;
608 zio
->io_orig_size
= zio
->io_size
= psize
;
609 zio
->io_lsize
= lsize
;
610 zio
->io_orig_flags
= zio
->io_flags
= flags
;
611 zio
->io_orig_stage
= zio
->io_stage
= stage
;
612 zio
->io_orig_pipeline
= zio
->io_pipeline
= pipeline
;
613 zio
->io_pipeline_trace
= ZIO_STAGE_OPEN
;
615 zio
->io_state
[ZIO_WAIT_READY
] = (stage
>= ZIO_STAGE_READY
);
616 zio
->io_state
[ZIO_WAIT_DONE
] = (stage
>= ZIO_STAGE_DONE
);
619 zio
->io_bookmark
= *zb
;
622 if (zio
->io_logical
== NULL
)
623 zio
->io_logical
= pio
->io_logical
;
624 if (zio
->io_child_type
== ZIO_CHILD_GANG
)
625 zio
->io_gang_leader
= pio
->io_gang_leader
;
626 zio_add_child(pio
, zio
);
633 zio_destroy(zio_t
*zio
)
635 metaslab_trace_fini(&zio
->io_alloc_list
);
636 list_destroy(&zio
->io_parent_list
);
637 list_destroy(&zio
->io_child_list
);
638 mutex_destroy(&zio
->io_lock
);
639 cv_destroy(&zio
->io_cv
);
640 kmem_cache_free(zio_cache
, zio
);
644 zio_null(zio_t
*pio
, spa_t
*spa
, vdev_t
*vd
, zio_done_func_t
*done
,
645 void *private, enum zio_flag flags
)
649 zio
= zio_create(pio
, spa
, 0, NULL
, NULL
, 0, 0, done
, private,
650 ZIO_TYPE_NULL
, ZIO_PRIORITY_NOW
, flags
, vd
, 0, NULL
,
651 ZIO_STAGE_OPEN
, ZIO_INTERLOCK_PIPELINE
);
657 zio_root(spa_t
*spa
, zio_done_func_t
*done
, void *private, enum zio_flag flags
)
659 return (zio_null(NULL
, spa
, NULL
, done
, private, flags
));
663 zfs_blkptr_verify(spa_t
*spa
, const blkptr_t
*bp
)
665 if (!DMU_OT_IS_VALID(BP_GET_TYPE(bp
))) {
666 zfs_panic_recover("blkptr at %p has invalid TYPE %llu",
667 bp
, (longlong_t
)BP_GET_TYPE(bp
));
669 if (BP_GET_CHECKSUM(bp
) >= ZIO_CHECKSUM_FUNCTIONS
||
670 BP_GET_CHECKSUM(bp
) <= ZIO_CHECKSUM_ON
) {
671 zfs_panic_recover("blkptr at %p has invalid CHECKSUM %llu",
672 bp
, (longlong_t
)BP_GET_CHECKSUM(bp
));
674 if (BP_GET_COMPRESS(bp
) >= ZIO_COMPRESS_FUNCTIONS
||
675 BP_GET_COMPRESS(bp
) <= ZIO_COMPRESS_ON
) {
676 zfs_panic_recover("blkptr at %p has invalid COMPRESS %llu",
677 bp
, (longlong_t
)BP_GET_COMPRESS(bp
));
679 if (BP_GET_LSIZE(bp
) > SPA_MAXBLOCKSIZE
) {
680 zfs_panic_recover("blkptr at %p has invalid LSIZE %llu",
681 bp
, (longlong_t
)BP_GET_LSIZE(bp
));
683 if (BP_GET_PSIZE(bp
) > SPA_MAXBLOCKSIZE
) {
684 zfs_panic_recover("blkptr at %p has invalid PSIZE %llu",
685 bp
, (longlong_t
)BP_GET_PSIZE(bp
));
688 if (BP_IS_EMBEDDED(bp
)) {
689 if (BPE_GET_ETYPE(bp
) > NUM_BP_EMBEDDED_TYPES
) {
690 zfs_panic_recover("blkptr at %p has invalid ETYPE %llu",
691 bp
, (longlong_t
)BPE_GET_ETYPE(bp
));
696 * Do not verify individual DVAs if the config is not trusted. This
697 * will be done once the zio is executed in vdev_mirror_map_alloc.
699 if (!spa
->spa_trust_config
)
703 * Pool-specific checks.
705 * Note: it would be nice to verify that the blk_birth and
706 * BP_PHYSICAL_BIRTH() are not too large. However, spa_freeze()
707 * allows the birth time of log blocks (and dmu_sync()-ed blocks
708 * that are in the log) to be arbitrarily large.
710 for (int i
= 0; i
< BP_GET_NDVAS(bp
); i
++) {
711 uint64_t vdevid
= DVA_GET_VDEV(&bp
->blk_dva
[i
]);
712 if (vdevid
>= spa
->spa_root_vdev
->vdev_children
) {
713 zfs_panic_recover("blkptr at %p DVA %u has invalid "
715 bp
, i
, (longlong_t
)vdevid
);
718 vdev_t
*vd
= spa
->spa_root_vdev
->vdev_child
[vdevid
];
720 zfs_panic_recover("blkptr at %p DVA %u has invalid "
722 bp
, i
, (longlong_t
)vdevid
);
725 if (vd
->vdev_ops
== &vdev_hole_ops
) {
726 zfs_panic_recover("blkptr at %p DVA %u has hole "
728 bp
, i
, (longlong_t
)vdevid
);
731 if (vd
->vdev_ops
== &vdev_missing_ops
) {
733 * "missing" vdevs are valid during import, but we
734 * don't have their detailed info (e.g. asize), so
735 * we can't perform any more checks on them.
739 uint64_t offset
= DVA_GET_OFFSET(&bp
->blk_dva
[i
]);
740 uint64_t asize
= DVA_GET_ASIZE(&bp
->blk_dva
[i
]);
742 asize
= vdev_psize_to_asize(vd
, SPA_GANGBLOCKSIZE
);
743 if (offset
+ asize
> vd
->vdev_asize
) {
744 zfs_panic_recover("blkptr at %p DVA %u has invalid "
746 bp
, i
, (longlong_t
)offset
);
752 zfs_dva_valid(spa_t
*spa
, const dva_t
*dva
, const blkptr_t
*bp
)
754 uint64_t vdevid
= DVA_GET_VDEV(dva
);
756 if (vdevid
>= spa
->spa_root_vdev
->vdev_children
)
759 vdev_t
*vd
= spa
->spa_root_vdev
->vdev_child
[vdevid
];
763 if (vd
->vdev_ops
== &vdev_hole_ops
)
766 if (vd
->vdev_ops
== &vdev_missing_ops
) {
770 uint64_t offset
= DVA_GET_OFFSET(dva
);
771 uint64_t asize
= DVA_GET_ASIZE(dva
);
774 asize
= vdev_psize_to_asize(vd
, SPA_GANGBLOCKSIZE
);
775 if (offset
+ asize
> vd
->vdev_asize
)
782 zio_read(zio_t
*pio
, spa_t
*spa
, const blkptr_t
*bp
,
783 abd_t
*data
, uint64_t size
, zio_done_func_t
*done
, void *private,
784 zio_priority_t priority
, enum zio_flag flags
, const zbookmark_phys_t
*zb
)
788 zfs_blkptr_verify(spa
, bp
);
790 zio
= zio_create(pio
, spa
, BP_PHYSICAL_BIRTH(bp
), bp
,
791 data
, size
, size
, done
, private,
792 ZIO_TYPE_READ
, priority
, flags
, NULL
, 0, zb
,
793 ZIO_STAGE_OPEN
, (flags
& ZIO_FLAG_DDT_CHILD
) ?
794 ZIO_DDT_CHILD_READ_PIPELINE
: ZIO_READ_PIPELINE
);
800 zio_write(zio_t
*pio
, spa_t
*spa
, uint64_t txg
, blkptr_t
*bp
,
801 abd_t
*data
, uint64_t lsize
, uint64_t psize
, const zio_prop_t
*zp
,
802 zio_done_func_t
*ready
, zio_done_func_t
*children_ready
,
803 zio_done_func_t
*physdone
, zio_done_func_t
*done
,
804 void *private, zio_priority_t priority
, enum zio_flag flags
,
805 const zbookmark_phys_t
*zb
)
809 ASSERT(zp
->zp_checksum
>= ZIO_CHECKSUM_OFF
&&
810 zp
->zp_checksum
< ZIO_CHECKSUM_FUNCTIONS
&&
811 zp
->zp_compress
>= ZIO_COMPRESS_OFF
&&
812 zp
->zp_compress
< ZIO_COMPRESS_FUNCTIONS
&&
813 DMU_OT_IS_VALID(zp
->zp_type
) &&
816 zp
->zp_copies
<= spa_max_replication(spa
));
818 zio
= zio_create(pio
, spa
, txg
, bp
, data
, lsize
, psize
, done
, private,
819 ZIO_TYPE_WRITE
, priority
, flags
, NULL
, 0, zb
,
820 ZIO_STAGE_OPEN
, (flags
& ZIO_FLAG_DDT_CHILD
) ?
821 ZIO_DDT_CHILD_WRITE_PIPELINE
: ZIO_WRITE_PIPELINE
);
823 zio
->io_ready
= ready
;
824 zio
->io_children_ready
= children_ready
;
825 zio
->io_physdone
= physdone
;
829 * Data can be NULL if we are going to call zio_write_override() to
830 * provide the already-allocated BP. But we may need the data to
831 * verify a dedup hit (if requested). In this case, don't try to
832 * dedup (just take the already-allocated BP verbatim).
834 if (data
== NULL
&& zio
->io_prop
.zp_dedup_verify
) {
835 zio
->io_prop
.zp_dedup
= zio
->io_prop
.zp_dedup_verify
= B_FALSE
;
842 zio_rewrite(zio_t
*pio
, spa_t
*spa
, uint64_t txg
, blkptr_t
*bp
, abd_t
*data
,
843 uint64_t size
, zio_done_func_t
*done
, void *private,
844 zio_priority_t priority
, enum zio_flag flags
, zbookmark_phys_t
*zb
)
848 zio
= zio_create(pio
, spa
, txg
, bp
, data
, size
, size
, done
, private,
849 ZIO_TYPE_WRITE
, priority
, flags
| ZIO_FLAG_IO_REWRITE
, NULL
, 0, zb
,
850 ZIO_STAGE_OPEN
, ZIO_REWRITE_PIPELINE
);
856 zio_write_override(zio_t
*zio
, blkptr_t
*bp
, int copies
, boolean_t nopwrite
)
858 ASSERT(zio
->io_type
== ZIO_TYPE_WRITE
);
859 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
860 ASSERT(zio
->io_stage
== ZIO_STAGE_OPEN
);
861 ASSERT(zio
->io_txg
== spa_syncing_txg(zio
->io_spa
));
864 * We must reset the io_prop to match the values that existed
865 * when the bp was first written by dmu_sync() keeping in mind
866 * that nopwrite and dedup are mutually exclusive.
868 zio
->io_prop
.zp_dedup
= nopwrite
? B_FALSE
: zio
->io_prop
.zp_dedup
;
869 zio
->io_prop
.zp_nopwrite
= nopwrite
;
870 zio
->io_prop
.zp_copies
= copies
;
871 zio
->io_bp_override
= bp
;
875 zio_free(spa_t
*spa
, uint64_t txg
, const blkptr_t
*bp
)
878 zfs_blkptr_verify(spa
, bp
);
881 * The check for EMBEDDED is a performance optimization. We
882 * process the free here (by ignoring it) rather than
883 * putting it on the list and then processing it in zio_free_sync().
885 if (BP_IS_EMBEDDED(bp
))
887 metaslab_check_free(spa
, bp
);
890 * Frees that are for the currently-syncing txg, are not going to be
891 * deferred, and which will not need to do a read (i.e. not GANG or
892 * DEDUP), can be processed immediately. Otherwise, put them on the
893 * in-memory list for later processing.
895 if (BP_IS_GANG(bp
) || BP_GET_DEDUP(bp
) ||
896 txg
!= spa
->spa_syncing_txg
||
897 spa_sync_pass(spa
) >= zfs_sync_pass_deferred_free
) {
898 bplist_append(&spa
->spa_free_bplist
[txg
& TXG_MASK
], bp
);
900 VERIFY0(zio_wait(zio_free_sync(NULL
, spa
, txg
, bp
, 0)));
905 zio_free_sync(zio_t
*pio
, spa_t
*spa
, uint64_t txg
, const blkptr_t
*bp
,
909 enum zio_stage stage
= ZIO_FREE_PIPELINE
;
911 ASSERT(!BP_IS_HOLE(bp
));
912 ASSERT(spa_syncing_txg(spa
) == txg
);
913 ASSERT(spa_sync_pass(spa
) < zfs_sync_pass_deferred_free
);
915 if (BP_IS_EMBEDDED(bp
))
916 return (zio_null(pio
, spa
, NULL
, NULL
, NULL
, 0));
918 metaslab_check_free(spa
, bp
);
922 * GANG and DEDUP blocks can induce a read (for the gang block header,
923 * or the DDT), so issue them asynchronously so that this thread is
926 if (BP_IS_GANG(bp
) || BP_GET_DEDUP(bp
))
927 stage
|= ZIO_STAGE_ISSUE_ASYNC
;
929 zio
= zio_create(pio
, spa
, txg
, bp
, NULL
, BP_GET_PSIZE(bp
),
930 BP_GET_PSIZE(bp
), NULL
, NULL
, ZIO_TYPE_FREE
, ZIO_PRIORITY_NOW
,
931 flags
, NULL
, 0, NULL
, ZIO_STAGE_OPEN
, stage
);
937 zio_claim(zio_t
*pio
, spa_t
*spa
, uint64_t txg
, const blkptr_t
*bp
,
938 zio_done_func_t
*done
, void *private, enum zio_flag flags
)
942 zfs_blkptr_verify(spa
, bp
);
944 if (BP_IS_EMBEDDED(bp
))
945 return (zio_null(pio
, spa
, NULL
, NULL
, NULL
, 0));
948 * A claim is an allocation of a specific block. Claims are needed
949 * to support immediate writes in the intent log. The issue is that
950 * immediate writes contain committed data, but in a txg that was
951 * *not* committed. Upon opening the pool after an unclean shutdown,
952 * the intent log claims all blocks that contain immediate write data
953 * so that the SPA knows they're in use.
955 * All claims *must* be resolved in the first txg -- before the SPA
956 * starts allocating blocks -- so that nothing is allocated twice.
957 * If txg == 0 we just verify that the block is claimable.
959 ASSERT3U(spa
->spa_uberblock
.ub_rootbp
.blk_birth
, <, spa_first_txg(spa
));
960 ASSERT(txg
== spa_first_txg(spa
) || txg
== 0);
961 ASSERT(!BP_GET_DEDUP(bp
) || !spa_writeable(spa
)); /* zdb(1M) */
963 zio
= zio_create(pio
, spa
, txg
, bp
, NULL
, BP_GET_PSIZE(bp
),
964 BP_GET_PSIZE(bp
), done
, private, ZIO_TYPE_CLAIM
, ZIO_PRIORITY_NOW
,
965 flags
, NULL
, 0, NULL
, ZIO_STAGE_OPEN
, ZIO_CLAIM_PIPELINE
);
966 ASSERT0(zio
->io_queued_timestamp
);
972 zio_ioctl(zio_t
*pio
, spa_t
*spa
, vdev_t
*vd
, int cmd
,
973 zio_done_func_t
*done
, void *private, enum zio_flag flags
)
978 if (vd
->vdev_children
== 0) {
979 zio
= zio_create(pio
, spa
, 0, NULL
, NULL
, 0, 0, done
, private,
980 ZIO_TYPE_IOCTL
, ZIO_PRIORITY_NOW
, flags
, vd
, 0, NULL
,
981 ZIO_STAGE_OPEN
, ZIO_IOCTL_PIPELINE
);
985 zio
= zio_null(pio
, spa
, NULL
, NULL
, NULL
, flags
);
987 for (c
= 0; c
< vd
->vdev_children
; c
++)
988 zio_nowait(zio_ioctl(zio
, spa
, vd
->vdev_child
[c
], cmd
,
989 done
, private, flags
));
996 zio_read_phys(zio_t
*pio
, vdev_t
*vd
, uint64_t offset
, uint64_t size
,
997 abd_t
*data
, int checksum
, zio_done_func_t
*done
, void *private,
998 zio_priority_t priority
, enum zio_flag flags
, boolean_t labels
)
1002 ASSERT(vd
->vdev_children
== 0);
1003 ASSERT(!labels
|| offset
+ size
<= VDEV_LABEL_START_SIZE
||
1004 offset
>= vd
->vdev_psize
- VDEV_LABEL_END_SIZE
);
1005 ASSERT3U(offset
+ size
, <=, vd
->vdev_psize
);
1007 zio
= zio_create(pio
, vd
->vdev_spa
, 0, NULL
, data
, size
, size
, done
,
1008 private, ZIO_TYPE_READ
, priority
, flags
| ZIO_FLAG_PHYSICAL
, vd
,
1009 offset
, NULL
, ZIO_STAGE_OPEN
, ZIO_READ_PHYS_PIPELINE
);
1011 zio
->io_prop
.zp_checksum
= checksum
;
1017 zio_write_phys(zio_t
*pio
, vdev_t
*vd
, uint64_t offset
, uint64_t size
,
1018 abd_t
*data
, int checksum
, zio_done_func_t
*done
, void *private,
1019 zio_priority_t priority
, enum zio_flag flags
, boolean_t labels
)
1023 ASSERT(vd
->vdev_children
== 0);
1024 ASSERT(!labels
|| offset
+ size
<= VDEV_LABEL_START_SIZE
||
1025 offset
>= vd
->vdev_psize
- VDEV_LABEL_END_SIZE
);
1026 ASSERT3U(offset
+ size
, <=, vd
->vdev_psize
);
1028 zio
= zio_create(pio
, vd
->vdev_spa
, 0, NULL
, data
, size
, size
, done
,
1029 private, ZIO_TYPE_WRITE
, priority
, flags
| ZIO_FLAG_PHYSICAL
, vd
,
1030 offset
, NULL
, ZIO_STAGE_OPEN
, ZIO_WRITE_PHYS_PIPELINE
);
1032 zio
->io_prop
.zp_checksum
= checksum
;
1034 if (zio_checksum_table
[checksum
].ci_flags
& ZCHECKSUM_FLAG_EMBEDDED
) {
1036 * zec checksums are necessarily destructive -- they modify
1037 * the end of the write buffer to hold the verifier/checksum.
1038 * Therefore, we must make a local copy in case the data is
1039 * being written to multiple places in parallel.
1041 abd_t
*wbuf
= abd_alloc_sametype(data
, size
);
1042 abd_copy(wbuf
, data
, size
);
1044 zio_push_transform(zio
, wbuf
, size
, size
, NULL
);
1051 * Create a child I/O to do some work for us.
1054 zio_vdev_child_io(zio_t
*pio
, blkptr_t
*bp
, vdev_t
*vd
, uint64_t offset
,
1055 abd_t
*data
, uint64_t size
, int type
, zio_priority_t priority
,
1056 enum zio_flag flags
, zio_done_func_t
*done
, void *private)
1058 enum zio_stage pipeline
= ZIO_VDEV_CHILD_PIPELINE
;
1062 * vdev child I/Os do not propagate their error to the parent.
1063 * Therefore, for correct operation the caller *must* check for
1064 * and handle the error in the child i/o's done callback.
1065 * The only exceptions are i/os that we don't care about
1066 * (OPTIONAL or REPAIR).
1068 ASSERT((flags
& ZIO_FLAG_OPTIONAL
) || (flags
& ZIO_FLAG_IO_REPAIR
) ||
1072 * In the common case, where the parent zio was to a normal vdev,
1073 * the child zio must be to a child vdev of that vdev. Otherwise,
1074 * the child zio must be to a top-level vdev.
1076 if (pio
->io_vd
!= NULL
&& pio
->io_vd
->vdev_ops
!= &vdev_indirect_ops
) {
1077 ASSERT3P(vd
->vdev_parent
, ==, pio
->io_vd
);
1079 ASSERT3P(vd
, ==, vd
->vdev_top
);
1082 if (type
== ZIO_TYPE_READ
&& bp
!= NULL
) {
1084 * If we have the bp, then the child should perform the
1085 * checksum and the parent need not. This pushes error
1086 * detection as close to the leaves as possible and
1087 * eliminates redundant checksums in the interior nodes.
1089 pipeline
|= ZIO_STAGE_CHECKSUM_VERIFY
;
1090 pio
->io_pipeline
&= ~ZIO_STAGE_CHECKSUM_VERIFY
;
1093 if (vd
->vdev_ops
->vdev_op_leaf
) {
1094 ASSERT0(vd
->vdev_children
);
1095 offset
+= VDEV_LABEL_START_SIZE
;
1098 flags
|= ZIO_VDEV_CHILD_FLAGS(pio
);
1101 * If we've decided to do a repair, the write is not speculative --
1102 * even if the original read was.
1104 if (flags
& ZIO_FLAG_IO_REPAIR
)
1105 flags
&= ~ZIO_FLAG_SPECULATIVE
;
1108 * If we're creating a child I/O that is not associated with a
1109 * top-level vdev, then the child zio is not an allocating I/O.
1110 * If this is a retried I/O then we ignore it since we will
1111 * have already processed the original allocating I/O.
1113 if (flags
& ZIO_FLAG_IO_ALLOCATING
&&
1114 (vd
!= vd
->vdev_top
|| (flags
& ZIO_FLAG_IO_RETRY
))) {
1115 metaslab_class_t
*mc
= spa_normal_class(pio
->io_spa
);
1117 ASSERT(mc
->mc_alloc_throttle_enabled
);
1118 ASSERT(type
== ZIO_TYPE_WRITE
);
1119 ASSERT(priority
== ZIO_PRIORITY_ASYNC_WRITE
);
1120 ASSERT(!(flags
& ZIO_FLAG_IO_REPAIR
));
1121 ASSERT(!(pio
->io_flags
& ZIO_FLAG_IO_REWRITE
) ||
1122 pio
->io_child_type
== ZIO_CHILD_GANG
);
1124 flags
&= ~ZIO_FLAG_IO_ALLOCATING
;
1127 zio
= zio_create(pio
, pio
->io_spa
, pio
->io_txg
, bp
, data
, size
, size
,
1128 done
, private, type
, priority
, flags
, vd
, offset
, &pio
->io_bookmark
,
1129 ZIO_STAGE_VDEV_IO_START
>> 1, pipeline
);
1130 ASSERT3U(zio
->io_child_type
, ==, ZIO_CHILD_VDEV
);
1132 zio
->io_physdone
= pio
->io_physdone
;
1133 if (vd
->vdev_ops
->vdev_op_leaf
&& zio
->io_logical
!= NULL
)
1134 zio
->io_logical
->io_phys_children
++;
1140 zio_vdev_delegated_io(vdev_t
*vd
, uint64_t offset
, abd_t
*data
, uint64_t size
,
1141 int type
, zio_priority_t priority
, enum zio_flag flags
,
1142 zio_done_func_t
*done
, void *private)
1146 ASSERT(vd
->vdev_ops
->vdev_op_leaf
);
1148 zio
= zio_create(NULL
, vd
->vdev_spa
, 0, NULL
,
1149 data
, size
, size
, done
, private, type
, priority
,
1150 flags
| ZIO_FLAG_CANFAIL
| ZIO_FLAG_DONT_RETRY
| ZIO_FLAG_DELEGATED
,
1152 ZIO_STAGE_VDEV_IO_START
>> 1, ZIO_VDEV_CHILD_PIPELINE
);
1158 zio_flush(zio_t
*zio
, vdev_t
*vd
)
1160 zio_nowait(zio_ioctl(zio
, zio
->io_spa
, vd
, DKIOCFLUSHWRITECACHE
,
1162 ZIO_FLAG_CANFAIL
| ZIO_FLAG_DONT_PROPAGATE
| ZIO_FLAG_DONT_RETRY
));
1166 zio_shrink(zio_t
*zio
, uint64_t size
)
1168 ASSERT3P(zio
->io_executor
, ==, NULL
);
1169 ASSERT3P(zio
->io_orig_size
, ==, zio
->io_size
);
1170 ASSERT3U(size
, <=, zio
->io_size
);
1173 * We don't shrink for raidz because of problems with the
1174 * reconstruction when reading back less than the block size.
1175 * Note, BP_IS_RAIDZ() assumes no compression.
1177 ASSERT(BP_GET_COMPRESS(zio
->io_bp
) == ZIO_COMPRESS_OFF
);
1178 if (!BP_IS_RAIDZ(zio
->io_bp
)) {
1179 /* we are not doing a raw write */
1180 ASSERT3U(zio
->io_size
, ==, zio
->io_lsize
);
1181 zio
->io_orig_size
= zio
->io_size
= zio
->io_lsize
= size
;
1186 * ==========================================================================
1187 * Prepare to read and write logical blocks
1188 * ==========================================================================
1192 zio_read_bp_init(zio_t
*zio
)
1194 blkptr_t
*bp
= zio
->io_bp
;
1196 ASSERT3P(zio
->io_bp
, ==, &zio
->io_bp_copy
);
1198 if (BP_GET_COMPRESS(bp
) != ZIO_COMPRESS_OFF
&&
1199 zio
->io_child_type
== ZIO_CHILD_LOGICAL
&&
1200 !(zio
->io_flags
& ZIO_FLAG_RAW
)) {
1202 BP_IS_EMBEDDED(bp
) ? BPE_GET_PSIZE(bp
) : BP_GET_PSIZE(bp
);
1203 zio_push_transform(zio
, abd_alloc_sametype(zio
->io_abd
, psize
),
1204 psize
, psize
, zio_decompress
);
1207 if (BP_IS_EMBEDDED(bp
) && BPE_GET_ETYPE(bp
) == BP_EMBEDDED_TYPE_DATA
) {
1208 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
1210 int psize
= BPE_GET_PSIZE(bp
);
1211 void *data
= abd_borrow_buf(zio
->io_abd
, psize
);
1212 decode_embedded_bp_compressed(bp
, data
);
1213 abd_return_buf_copy(zio
->io_abd
, data
, psize
);
1215 ASSERT(!BP_IS_EMBEDDED(bp
));
1216 ASSERT3P(zio
->io_bp
, ==, &zio
->io_bp_copy
);
1219 if (!DMU_OT_IS_METADATA(BP_GET_TYPE(bp
)) && BP_GET_LEVEL(bp
) == 0)
1220 zio
->io_flags
|= ZIO_FLAG_DONT_CACHE
;
1222 if (BP_GET_TYPE(bp
) == DMU_OT_DDT_ZAP
)
1223 zio
->io_flags
|= ZIO_FLAG_DONT_CACHE
;
1225 if (BP_GET_DEDUP(bp
) && zio
->io_child_type
== ZIO_CHILD_LOGICAL
)
1226 zio
->io_pipeline
= ZIO_DDT_READ_PIPELINE
;
1228 return (ZIO_PIPELINE_CONTINUE
);
1232 zio_write_bp_init(zio_t
*zio
)
1234 if (!IO_IS_ALLOCATING(zio
))
1235 return (ZIO_PIPELINE_CONTINUE
);
1237 ASSERT(zio
->io_child_type
!= ZIO_CHILD_DDT
);
1239 if (zio
->io_bp_override
) {
1240 blkptr_t
*bp
= zio
->io_bp
;
1241 zio_prop_t
*zp
= &zio
->io_prop
;
1243 ASSERT(bp
->blk_birth
!= zio
->io_txg
);
1244 ASSERT(BP_GET_DEDUP(zio
->io_bp_override
) == 0);
1246 *bp
= *zio
->io_bp_override
;
1247 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
1249 if (BP_IS_EMBEDDED(bp
))
1250 return (ZIO_PIPELINE_CONTINUE
);
1253 * If we've been overridden and nopwrite is set then
1254 * set the flag accordingly to indicate that a nopwrite
1255 * has already occurred.
1257 if (!BP_IS_HOLE(bp
) && zp
->zp_nopwrite
) {
1258 ASSERT(!zp
->zp_dedup
);
1259 ASSERT3U(BP_GET_CHECKSUM(bp
), ==, zp
->zp_checksum
);
1260 zio
->io_flags
|= ZIO_FLAG_NOPWRITE
;
1261 return (ZIO_PIPELINE_CONTINUE
);
1264 ASSERT(!zp
->zp_nopwrite
);
1266 if (BP_IS_HOLE(bp
) || !zp
->zp_dedup
)
1267 return (ZIO_PIPELINE_CONTINUE
);
1269 ASSERT((zio_checksum_table
[zp
->zp_checksum
].ci_flags
&
1270 ZCHECKSUM_FLAG_DEDUP
) || zp
->zp_dedup_verify
);
1272 if (BP_GET_CHECKSUM(bp
) == zp
->zp_checksum
) {
1273 BP_SET_DEDUP(bp
, 1);
1274 zio
->io_pipeline
|= ZIO_STAGE_DDT_WRITE
;
1275 return (ZIO_PIPELINE_CONTINUE
);
1279 * We were unable to handle this as an override bp, treat
1280 * it as a regular write I/O.
1282 zio
->io_bp_override
= NULL
;
1283 *bp
= zio
->io_bp_orig
;
1284 zio
->io_pipeline
= zio
->io_orig_pipeline
;
1287 return (ZIO_PIPELINE_CONTINUE
);
1291 zio_write_compress(zio_t
*zio
)
1293 spa_t
*spa
= zio
->io_spa
;
1294 zio_prop_t
*zp
= &zio
->io_prop
;
1295 enum zio_compress compress
= zp
->zp_compress
;
1296 blkptr_t
*bp
= zio
->io_bp
;
1297 uint64_t lsize
= zio
->io_lsize
;
1298 uint64_t psize
= zio
->io_size
;
1301 EQUIV(lsize
!= psize
, (zio
->io_flags
& ZIO_FLAG_RAW
) != 0);
1304 * If our children haven't all reached the ready stage,
1305 * wait for them and then repeat this pipeline stage.
1307 if (zio_wait_for_children(zio
, ZIO_CHILD_LOGICAL_BIT
|
1308 ZIO_CHILD_GANG_BIT
, ZIO_WAIT_READY
)) {
1309 return (ZIO_PIPELINE_STOP
);
1312 if (!IO_IS_ALLOCATING(zio
))
1313 return (ZIO_PIPELINE_CONTINUE
);
1315 if (zio
->io_children_ready
!= NULL
) {
1317 * Now that all our children are ready, run the callback
1318 * associated with this zio in case it wants to modify the
1319 * data to be written.
1321 ASSERT3U(zp
->zp_level
, >, 0);
1322 zio
->io_children_ready(zio
);
1325 ASSERT(zio
->io_child_type
!= ZIO_CHILD_DDT
);
1326 ASSERT(zio
->io_bp_override
== NULL
);
1328 if (!BP_IS_HOLE(bp
) && bp
->blk_birth
== zio
->io_txg
) {
1330 * We're rewriting an existing block, which means we're
1331 * working on behalf of spa_sync(). For spa_sync() to
1332 * converge, it must eventually be the case that we don't
1333 * have to allocate new blocks. But compression changes
1334 * the blocksize, which forces a reallocate, and makes
1335 * convergence take longer. Therefore, after the first
1336 * few passes, stop compressing to ensure convergence.
1338 pass
= spa_sync_pass(spa
);
1340 ASSERT(zio
->io_txg
== spa_syncing_txg(spa
));
1341 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
1342 ASSERT(!BP_GET_DEDUP(bp
));
1344 if (pass
>= zfs_sync_pass_dont_compress
)
1345 compress
= ZIO_COMPRESS_OFF
;
1347 /* Make sure someone doesn't change their mind on overwrites */
1348 ASSERT(BP_IS_EMBEDDED(bp
) || MIN(zp
->zp_copies
+ BP_IS_GANG(bp
),
1349 spa_max_replication(spa
)) == BP_GET_NDVAS(bp
));
1352 /* If it's a compressed write that is not raw, compress the buffer. */
1353 if (compress
!= ZIO_COMPRESS_OFF
&& psize
== lsize
) {
1354 void *cbuf
= zio_buf_alloc(lsize
);
1355 psize
= zio_compress_data(compress
, zio
->io_abd
, cbuf
, lsize
);
1356 if (psize
== 0 || psize
== lsize
) {
1357 compress
= ZIO_COMPRESS_OFF
;
1358 zio_buf_free(cbuf
, lsize
);
1359 } else if (!zp
->zp_dedup
&& psize
<= BPE_PAYLOAD_SIZE
&&
1360 zp
->zp_level
== 0 && !DMU_OT_HAS_FILL(zp
->zp_type
) &&
1361 spa_feature_is_enabled(spa
, SPA_FEATURE_EMBEDDED_DATA
)) {
1362 encode_embedded_bp_compressed(bp
,
1363 cbuf
, compress
, lsize
, psize
);
1364 BPE_SET_ETYPE(bp
, BP_EMBEDDED_TYPE_DATA
);
1365 BP_SET_TYPE(bp
, zio
->io_prop
.zp_type
);
1366 BP_SET_LEVEL(bp
, zio
->io_prop
.zp_level
);
1367 zio_buf_free(cbuf
, lsize
);
1368 bp
->blk_birth
= zio
->io_txg
;
1369 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
1370 ASSERT(spa_feature_is_active(spa
,
1371 SPA_FEATURE_EMBEDDED_DATA
));
1372 return (ZIO_PIPELINE_CONTINUE
);
1375 * Round up compressed size up to the ashift
1376 * of the smallest-ashift device, and zero the tail.
1377 * This ensures that the compressed size of the BP
1378 * (and thus compressratio property) are correct,
1379 * in that we charge for the padding used to fill out
1382 ASSERT3U(spa
->spa_min_ashift
, >=, SPA_MINBLOCKSHIFT
);
1383 size_t rounded
= (size_t)P2ROUNDUP(psize
,
1384 1ULL << spa
->spa_min_ashift
);
1385 if (rounded
>= lsize
) {
1386 compress
= ZIO_COMPRESS_OFF
;
1387 zio_buf_free(cbuf
, lsize
);
1390 abd_t
*cdata
= abd_get_from_buf(cbuf
, lsize
);
1391 abd_take_ownership_of_buf(cdata
, B_TRUE
);
1392 abd_zero_off(cdata
, psize
, rounded
- psize
);
1394 zio_push_transform(zio
, cdata
,
1395 psize
, lsize
, NULL
);
1400 * We were unable to handle this as an override bp, treat
1401 * it as a regular write I/O.
1403 zio
->io_bp_override
= NULL
;
1404 *bp
= zio
->io_bp_orig
;
1405 zio
->io_pipeline
= zio
->io_orig_pipeline
;
1407 ASSERT3U(psize
, !=, 0);
1411 * The final pass of spa_sync() must be all rewrites, but the first
1412 * few passes offer a trade-off: allocating blocks defers convergence,
1413 * but newly allocated blocks are sequential, so they can be written
1414 * to disk faster. Therefore, we allow the first few passes of
1415 * spa_sync() to allocate new blocks, but force rewrites after that.
1416 * There should only be a handful of blocks after pass 1 in any case.
1418 if (!BP_IS_HOLE(bp
) && bp
->blk_birth
== zio
->io_txg
&&
1419 BP_GET_PSIZE(bp
) == psize
&&
1420 pass
>= zfs_sync_pass_rewrite
) {
1422 enum zio_stage gang_stages
= zio
->io_pipeline
& ZIO_GANG_STAGES
;
1423 zio
->io_pipeline
= ZIO_REWRITE_PIPELINE
| gang_stages
;
1424 zio
->io_flags
|= ZIO_FLAG_IO_REWRITE
;
1427 zio
->io_pipeline
= ZIO_WRITE_PIPELINE
;
1431 if (zio
->io_bp_orig
.blk_birth
!= 0 &&
1432 spa_feature_is_active(spa
, SPA_FEATURE_HOLE_BIRTH
)) {
1433 BP_SET_LSIZE(bp
, lsize
);
1434 BP_SET_TYPE(bp
, zp
->zp_type
);
1435 BP_SET_LEVEL(bp
, zp
->zp_level
);
1436 BP_SET_BIRTH(bp
, zio
->io_txg
, 0);
1438 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
1440 ASSERT(zp
->zp_checksum
!= ZIO_CHECKSUM_GANG_HEADER
);
1441 BP_SET_LSIZE(bp
, lsize
);
1442 BP_SET_TYPE(bp
, zp
->zp_type
);
1443 BP_SET_LEVEL(bp
, zp
->zp_level
);
1444 BP_SET_PSIZE(bp
, psize
);
1445 BP_SET_COMPRESS(bp
, compress
);
1446 BP_SET_CHECKSUM(bp
, zp
->zp_checksum
);
1447 BP_SET_DEDUP(bp
, zp
->zp_dedup
);
1448 BP_SET_BYTEORDER(bp
, ZFS_HOST_BYTEORDER
);
1450 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
1451 ASSERT(!(zio
->io_flags
& ZIO_FLAG_IO_REWRITE
));
1452 zio
->io_pipeline
= ZIO_DDT_WRITE_PIPELINE
;
1454 if (zp
->zp_nopwrite
) {
1455 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
1456 ASSERT(!(zio
->io_flags
& ZIO_FLAG_IO_REWRITE
));
1457 zio
->io_pipeline
|= ZIO_STAGE_NOP_WRITE
;
1460 return (ZIO_PIPELINE_CONTINUE
);
1464 zio_free_bp_init(zio_t
*zio
)
1466 blkptr_t
*bp
= zio
->io_bp
;
1468 if (zio
->io_child_type
== ZIO_CHILD_LOGICAL
) {
1469 if (BP_GET_DEDUP(bp
))
1470 zio
->io_pipeline
= ZIO_DDT_FREE_PIPELINE
;
1473 ASSERT3P(zio
->io_bp
, ==, &zio
->io_bp_copy
);
1475 return (ZIO_PIPELINE_CONTINUE
);
1479 * ==========================================================================
1480 * Execute the I/O pipeline
1481 * ==========================================================================
1485 zio_taskq_dispatch(zio_t
*zio
, zio_taskq_type_t q
, boolean_t cutinline
)
1487 spa_t
*spa
= zio
->io_spa
;
1488 zio_type_t t
= zio
->io_type
;
1489 int flags
= (cutinline
? TQ_FRONT
: 0);
1492 * If we're a config writer or a probe, the normal issue and
1493 * interrupt threads may all be blocked waiting for the config lock.
1494 * In this case, select the otherwise-unused taskq for ZIO_TYPE_NULL.
1496 if (zio
->io_flags
& (ZIO_FLAG_CONFIG_WRITER
| ZIO_FLAG_PROBE
))
1500 * A similar issue exists for the L2ARC write thread until L2ARC 2.0.
1502 if (t
== ZIO_TYPE_WRITE
&& zio
->io_vd
&& zio
->io_vd
->vdev_aux
)
1506 * If this is a high priority I/O, then use the high priority taskq if
1509 if (zio
->io_priority
== ZIO_PRIORITY_NOW
&&
1510 spa
->spa_zio_taskq
[t
][q
+ 1].stqs_count
!= 0)
1513 ASSERT3U(q
, <, ZIO_TASKQ_TYPES
);
1516 * NB: We are assuming that the zio can only be dispatched
1517 * to a single taskq at a time. It would be a grievous error
1518 * to dispatch the zio to another taskq at the same time.
1520 ASSERT(zio
->io_tqent
.tqent_next
== NULL
);
1521 spa_taskq_dispatch_ent(spa
, t
, q
, (task_func_t
*)zio_execute
, zio
,
1522 flags
, &zio
->io_tqent
);
1526 zio_taskq_member(zio_t
*zio
, zio_taskq_type_t q
)
1528 kthread_t
*executor
= zio
->io_executor
;
1529 spa_t
*spa
= zio
->io_spa
;
1531 for (zio_type_t t
= 0; t
< ZIO_TYPES
; t
++) {
1532 spa_taskqs_t
*tqs
= &spa
->spa_zio_taskq
[t
][q
];
1534 for (i
= 0; i
< tqs
->stqs_count
; i
++) {
1535 if (taskq_member(tqs
->stqs_taskq
[i
], executor
))
1544 zio_issue_async(zio_t
*zio
)
1546 zio_taskq_dispatch(zio
, ZIO_TASKQ_ISSUE
, B_FALSE
);
1548 return (ZIO_PIPELINE_STOP
);
1552 zio_interrupt(zio_t
*zio
)
1554 zio_taskq_dispatch(zio
, ZIO_TASKQ_INTERRUPT
, B_FALSE
);
1558 zio_delay_interrupt(zio_t
*zio
)
1561 * The timeout_generic() function isn't defined in userspace, so
1562 * rather than trying to implement the function, the zio delay
1563 * functionality has been disabled for userspace builds.
1568 * If io_target_timestamp is zero, then no delay has been registered
1569 * for this IO, thus jump to the end of this function and "skip" the
1570 * delay; issuing it directly to the zio layer.
1572 if (zio
->io_target_timestamp
!= 0) {
1573 hrtime_t now
= gethrtime();
1575 if (now
>= zio
->io_target_timestamp
) {
1577 * This IO has already taken longer than the target
1578 * delay to complete, so we don't want to delay it
1579 * any longer; we "miss" the delay and issue it
1580 * directly to the zio layer. This is likely due to
1581 * the target latency being set to a value less than
1582 * the underlying hardware can satisfy (e.g. delay
1583 * set to 1ms, but the disks take 10ms to complete an
1587 DTRACE_PROBE2(zio__delay__miss
, zio_t
*, zio
,
1592 hrtime_t diff
= zio
->io_target_timestamp
- now
;
1594 DTRACE_PROBE3(zio__delay__hit
, zio_t
*, zio
,
1595 hrtime_t
, now
, hrtime_t
, diff
);
1597 (void) timeout_generic(CALLOUT_NORMAL
,
1598 (void (*)(void *))zio_interrupt
, zio
, diff
, 1, 0);
1605 DTRACE_PROBE1(zio__delay__skip
, zio_t
*, zio
);
1610 * Execute the I/O pipeline until one of the following occurs:
1612 * (1) the I/O completes
1613 * (2) the pipeline stalls waiting for dependent child I/Os
1614 * (3) the I/O issues, so we're waiting for an I/O completion interrupt
1615 * (4) the I/O is delegated by vdev-level caching or aggregation
1616 * (5) the I/O is deferred due to vdev-level queueing
1617 * (6) the I/O is handed off to another thread.
1619 * In all cases, the pipeline stops whenever there's no CPU work; it never
1620 * burns a thread in cv_wait().
1622 * There's no locking on io_stage because there's no legitimate way
1623 * for multiple threads to be attempting to process the same I/O.
1625 static zio_pipe_stage_t
*zio_pipeline
[];
1628 zio_execute(zio_t
*zio
)
1630 zio
->io_executor
= curthread
;
1632 ASSERT3U(zio
->io_queued_timestamp
, >, 0);
1634 while (zio
->io_stage
< ZIO_STAGE_DONE
) {
1635 enum zio_stage pipeline
= zio
->io_pipeline
;
1636 enum zio_stage stage
= zio
->io_stage
;
1639 ASSERT(!MUTEX_HELD(&zio
->io_lock
));
1640 ASSERT(ISP2(stage
));
1641 ASSERT(zio
->io_stall
== NULL
);
1645 } while ((stage
& pipeline
) == 0);
1647 ASSERT(stage
<= ZIO_STAGE_DONE
);
1650 * If we are in interrupt context and this pipeline stage
1651 * will grab a config lock that is held across I/O,
1652 * or may wait for an I/O that needs an interrupt thread
1653 * to complete, issue async to avoid deadlock.
1655 * For VDEV_IO_START, we cut in line so that the io will
1656 * be sent to disk promptly.
1658 if ((stage
& ZIO_BLOCKING_STAGES
) && zio
->io_vd
== NULL
&&
1659 zio_taskq_member(zio
, ZIO_TASKQ_INTERRUPT
)) {
1660 boolean_t cut
= (stage
== ZIO_STAGE_VDEV_IO_START
) ?
1661 zio_requeue_io_start_cut_in_line
: B_FALSE
;
1662 zio_taskq_dispatch(zio
, ZIO_TASKQ_ISSUE
, cut
);
1666 zio
->io_stage
= stage
;
1667 zio
->io_pipeline_trace
|= zio
->io_stage
;
1668 rv
= zio_pipeline
[highbit64(stage
) - 1](zio
);
1670 if (rv
== ZIO_PIPELINE_STOP
)
1673 ASSERT(rv
== ZIO_PIPELINE_CONTINUE
);
1678 * ==========================================================================
1679 * Initiate I/O, either sync or async
1680 * ==========================================================================
1683 zio_wait(zio_t
*zio
)
1687 ASSERT3P(zio
->io_stage
, ==, ZIO_STAGE_OPEN
);
1688 ASSERT3P(zio
->io_executor
, ==, NULL
);
1690 zio
->io_waiter
= curthread
;
1691 ASSERT0(zio
->io_queued_timestamp
);
1692 zio
->io_queued_timestamp
= gethrtime();
1696 mutex_enter(&zio
->io_lock
);
1697 while (zio
->io_executor
!= NULL
)
1698 cv_wait(&zio
->io_cv
, &zio
->io_lock
);
1699 mutex_exit(&zio
->io_lock
);
1701 error
= zio
->io_error
;
1708 zio_nowait(zio_t
*zio
)
1710 ASSERT3P(zio
->io_executor
, ==, NULL
);
1712 if (zio
->io_child_type
== ZIO_CHILD_LOGICAL
&&
1713 zio_unique_parent(zio
) == NULL
) {
1715 * This is a logical async I/O with no parent to wait for it.
1716 * We add it to the spa_async_root_zio "Godfather" I/O which
1717 * will ensure they complete prior to unloading the pool.
1719 spa_t
*spa
= zio
->io_spa
;
1721 zio_add_child(spa
->spa_async_zio_root
[CPU_SEQID
], zio
);
1724 ASSERT0(zio
->io_queued_timestamp
);
1725 zio
->io_queued_timestamp
= gethrtime();
1730 * ==========================================================================
1731 * Reexecute, cancel, or suspend/resume failed I/O
1732 * ==========================================================================
1736 zio_reexecute(zio_t
*pio
)
1738 zio_t
*cio
, *cio_next
;
1740 ASSERT(pio
->io_child_type
== ZIO_CHILD_LOGICAL
);
1741 ASSERT(pio
->io_orig_stage
== ZIO_STAGE_OPEN
);
1742 ASSERT(pio
->io_gang_leader
== NULL
);
1743 ASSERT(pio
->io_gang_tree
== NULL
);
1745 pio
->io_flags
= pio
->io_orig_flags
;
1746 pio
->io_stage
= pio
->io_orig_stage
;
1747 pio
->io_pipeline
= pio
->io_orig_pipeline
;
1748 pio
->io_reexecute
= 0;
1749 pio
->io_flags
|= ZIO_FLAG_REEXECUTED
;
1750 pio
->io_pipeline_trace
= 0;
1752 for (int w
= 0; w
< ZIO_WAIT_TYPES
; w
++)
1753 pio
->io_state
[w
] = 0;
1754 for (int c
= 0; c
< ZIO_CHILD_TYPES
; c
++)
1755 pio
->io_child_error
[c
] = 0;
1757 if (IO_IS_ALLOCATING(pio
))
1758 BP_ZERO(pio
->io_bp
);
1761 * As we reexecute pio's children, new children could be created.
1762 * New children go to the head of pio's io_child_list, however,
1763 * so we will (correctly) not reexecute them. The key is that
1764 * the remainder of pio's io_child_list, from 'cio_next' onward,
1765 * cannot be affected by any side effects of reexecuting 'cio'.
1767 zio_link_t
*zl
= NULL
;
1768 for (cio
= zio_walk_children(pio
, &zl
); cio
!= NULL
; cio
= cio_next
) {
1769 cio_next
= zio_walk_children(pio
, &zl
);
1770 mutex_enter(&pio
->io_lock
);
1771 for (int w
= 0; w
< ZIO_WAIT_TYPES
; w
++)
1772 pio
->io_children
[cio
->io_child_type
][w
]++;
1773 mutex_exit(&pio
->io_lock
);
1778 * Now that all children have been reexecuted, execute the parent.
1779 * We don't reexecute "The Godfather" I/O here as it's the
1780 * responsibility of the caller to wait on it.
1782 if (!(pio
->io_flags
& ZIO_FLAG_GODFATHER
)) {
1783 pio
->io_queued_timestamp
= gethrtime();
1789 zio_suspend(spa_t
*spa
, zio_t
*zio
)
1791 if (spa_get_failmode(spa
) == ZIO_FAILURE_MODE_PANIC
)
1792 fm_panic("Pool '%s' has encountered an uncorrectable I/O "
1793 "failure and the failure mode property for this pool "
1794 "is set to panic.", spa_name(spa
));
1796 zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE
, spa
, NULL
, NULL
, 0, 0);
1798 mutex_enter(&spa
->spa_suspend_lock
);
1800 if (spa
->spa_suspend_zio_root
== NULL
)
1801 spa
->spa_suspend_zio_root
= zio_root(spa
, NULL
, NULL
,
1802 ZIO_FLAG_CANFAIL
| ZIO_FLAG_SPECULATIVE
|
1803 ZIO_FLAG_GODFATHER
);
1805 spa
->spa_suspended
= B_TRUE
;
1808 ASSERT(!(zio
->io_flags
& ZIO_FLAG_GODFATHER
));
1809 ASSERT(zio
!= spa
->spa_suspend_zio_root
);
1810 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
1811 ASSERT(zio_unique_parent(zio
) == NULL
);
1812 ASSERT(zio
->io_stage
== ZIO_STAGE_DONE
);
1813 zio_add_child(spa
->spa_suspend_zio_root
, zio
);
1816 mutex_exit(&spa
->spa_suspend_lock
);
1820 zio_resume(spa_t
*spa
)
1825 * Reexecute all previously suspended i/o.
1827 mutex_enter(&spa
->spa_suspend_lock
);
1828 spa
->spa_suspended
= B_FALSE
;
1829 cv_broadcast(&spa
->spa_suspend_cv
);
1830 pio
= spa
->spa_suspend_zio_root
;
1831 spa
->spa_suspend_zio_root
= NULL
;
1832 mutex_exit(&spa
->spa_suspend_lock
);
1838 return (zio_wait(pio
));
1842 zio_resume_wait(spa_t
*spa
)
1844 mutex_enter(&spa
->spa_suspend_lock
);
1845 while (spa_suspended(spa
))
1846 cv_wait(&spa
->spa_suspend_cv
, &spa
->spa_suspend_lock
);
1847 mutex_exit(&spa
->spa_suspend_lock
);
1851 * ==========================================================================
1854 * A gang block is a collection of small blocks that looks to the DMU
1855 * like one large block. When zio_dva_allocate() cannot find a block
1856 * of the requested size, due to either severe fragmentation or the pool
1857 * being nearly full, it calls zio_write_gang_block() to construct the
1858 * block from smaller fragments.
1860 * A gang block consists of a gang header (zio_gbh_phys_t) and up to
1861 * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like
1862 * an indirect block: it's an array of block pointers. It consumes
1863 * only one sector and hence is allocatable regardless of fragmentation.
1864 * The gang header's bps point to its gang members, which hold the data.
1866 * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg>
1867 * as the verifier to ensure uniqueness of the SHA256 checksum.
1868 * Critically, the gang block bp's blk_cksum is the checksum of the data,
1869 * not the gang header. This ensures that data block signatures (needed for
1870 * deduplication) are independent of how the block is physically stored.
1872 * Gang blocks can be nested: a gang member may itself be a gang block.
1873 * Thus every gang block is a tree in which root and all interior nodes are
1874 * gang headers, and the leaves are normal blocks that contain user data.
1875 * The root of the gang tree is called the gang leader.
1877 * To perform any operation (read, rewrite, free, claim) on a gang block,
1878 * zio_gang_assemble() first assembles the gang tree (minus data leaves)
1879 * in the io_gang_tree field of the original logical i/o by recursively
1880 * reading the gang leader and all gang headers below it. This yields
1881 * an in-core tree containing the contents of every gang header and the
1882 * bps for every constituent of the gang block.
1884 * With the gang tree now assembled, zio_gang_issue() just walks the gang tree
1885 * and invokes a callback on each bp. To free a gang block, zio_gang_issue()
1886 * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp.
1887 * zio_claim_gang() provides a similarly trivial wrapper for zio_claim().
1888 * zio_read_gang() is a wrapper around zio_read() that omits reading gang
1889 * headers, since we already have those in io_gang_tree. zio_rewrite_gang()
1890 * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite()
1891 * of the gang header plus zio_checksum_compute() of the data to update the
1892 * gang header's blk_cksum as described above.
1894 * The two-phase assemble/issue model solves the problem of partial failure --
1895 * what if you'd freed part of a gang block but then couldn't read the
1896 * gang header for another part? Assembling the entire gang tree first
1897 * ensures that all the necessary gang header I/O has succeeded before
1898 * starting the actual work of free, claim, or write. Once the gang tree
1899 * is assembled, free and claim are in-memory operations that cannot fail.
1901 * In the event that a gang write fails, zio_dva_unallocate() walks the
1902 * gang tree to immediately free (i.e. insert back into the space map)
1903 * everything we've allocated. This ensures that we don't get ENOSPC
1904 * errors during repeated suspend/resume cycles due to a flaky device.
1906 * Gang rewrites only happen during sync-to-convergence. If we can't assemble
1907 * the gang tree, we won't modify the block, so we can safely defer the free
1908 * (knowing that the block is still intact). If we *can* assemble the gang
1909 * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free
1910 * each constituent bp and we can allocate a new block on the next sync pass.
1912 * In all cases, the gang tree allows complete recovery from partial failure.
1913 * ==========================================================================
1917 zio_gang_issue_func_done(zio_t
*zio
)
1919 abd_put(zio
->io_abd
);
1923 zio_read_gang(zio_t
*pio
, blkptr_t
*bp
, zio_gang_node_t
*gn
, abd_t
*data
,
1929 return (zio_read(pio
, pio
->io_spa
, bp
, abd_get_offset(data
, offset
),
1930 BP_GET_PSIZE(bp
), zio_gang_issue_func_done
,
1931 NULL
, pio
->io_priority
, ZIO_GANG_CHILD_FLAGS(pio
),
1932 &pio
->io_bookmark
));
1936 zio_rewrite_gang(zio_t
*pio
, blkptr_t
*bp
, zio_gang_node_t
*gn
, abd_t
*data
,
1943 abd_get_from_buf(gn
->gn_gbh
, SPA_GANGBLOCKSIZE
);
1944 zio
= zio_rewrite(pio
, pio
->io_spa
, pio
->io_txg
, bp
,
1945 gbh_abd
, SPA_GANGBLOCKSIZE
, zio_gang_issue_func_done
, NULL
,
1946 pio
->io_priority
, ZIO_GANG_CHILD_FLAGS(pio
),
1949 * As we rewrite each gang header, the pipeline will compute
1950 * a new gang block header checksum for it; but no one will
1951 * compute a new data checksum, so we do that here. The one
1952 * exception is the gang leader: the pipeline already computed
1953 * its data checksum because that stage precedes gang assembly.
1954 * (Presently, nothing actually uses interior data checksums;
1955 * this is just good hygiene.)
1957 if (gn
!= pio
->io_gang_leader
->io_gang_tree
) {
1958 abd_t
*buf
= abd_get_offset(data
, offset
);
1960 zio_checksum_compute(zio
, BP_GET_CHECKSUM(bp
),
1961 buf
, BP_GET_PSIZE(bp
));
1966 * If we are here to damage data for testing purposes,
1967 * leave the GBH alone so that we can detect the damage.
1969 if (pio
->io_gang_leader
->io_flags
& ZIO_FLAG_INDUCE_DAMAGE
)
1970 zio
->io_pipeline
&= ~ZIO_VDEV_IO_STAGES
;
1972 zio
= zio_rewrite(pio
, pio
->io_spa
, pio
->io_txg
, bp
,
1973 abd_get_offset(data
, offset
), BP_GET_PSIZE(bp
),
1974 zio_gang_issue_func_done
, NULL
, pio
->io_priority
,
1975 ZIO_GANG_CHILD_FLAGS(pio
), &pio
->io_bookmark
);
1983 zio_free_gang(zio_t
*pio
, blkptr_t
*bp
, zio_gang_node_t
*gn
, abd_t
*data
,
1986 return (zio_free_sync(pio
, pio
->io_spa
, pio
->io_txg
, bp
,
1987 ZIO_GANG_CHILD_FLAGS(pio
)));
1992 zio_claim_gang(zio_t
*pio
, blkptr_t
*bp
, zio_gang_node_t
*gn
, abd_t
*data
,
1995 return (zio_claim(pio
, pio
->io_spa
, pio
->io_txg
, bp
,
1996 NULL
, NULL
, ZIO_GANG_CHILD_FLAGS(pio
)));
1999 static zio_gang_issue_func_t
*zio_gang_issue_func
[ZIO_TYPES
] = {
2008 static void zio_gang_tree_assemble_done(zio_t
*zio
);
2010 static zio_gang_node_t
*
2011 zio_gang_node_alloc(zio_gang_node_t
**gnpp
)
2013 zio_gang_node_t
*gn
;
2015 ASSERT(*gnpp
== NULL
);
2017 gn
= kmem_zalloc(sizeof (*gn
), KM_SLEEP
);
2018 gn
->gn_gbh
= zio_buf_alloc(SPA_GANGBLOCKSIZE
);
2025 zio_gang_node_free(zio_gang_node_t
**gnpp
)
2027 zio_gang_node_t
*gn
= *gnpp
;
2029 for (int g
= 0; g
< SPA_GBH_NBLKPTRS
; g
++)
2030 ASSERT(gn
->gn_child
[g
] == NULL
);
2032 zio_buf_free(gn
->gn_gbh
, SPA_GANGBLOCKSIZE
);
2033 kmem_free(gn
, sizeof (*gn
));
2038 zio_gang_tree_free(zio_gang_node_t
**gnpp
)
2040 zio_gang_node_t
*gn
= *gnpp
;
2045 for (int g
= 0; g
< SPA_GBH_NBLKPTRS
; g
++)
2046 zio_gang_tree_free(&gn
->gn_child
[g
]);
2048 zio_gang_node_free(gnpp
);
2052 zio_gang_tree_assemble(zio_t
*gio
, blkptr_t
*bp
, zio_gang_node_t
**gnpp
)
2054 zio_gang_node_t
*gn
= zio_gang_node_alloc(gnpp
);
2055 abd_t
*gbh_abd
= abd_get_from_buf(gn
->gn_gbh
, SPA_GANGBLOCKSIZE
);
2057 ASSERT(gio
->io_gang_leader
== gio
);
2058 ASSERT(BP_IS_GANG(bp
));
2060 zio_nowait(zio_read(gio
, gio
->io_spa
, bp
, gbh_abd
, SPA_GANGBLOCKSIZE
,
2061 zio_gang_tree_assemble_done
, gn
, gio
->io_priority
,
2062 ZIO_GANG_CHILD_FLAGS(gio
), &gio
->io_bookmark
));
2066 zio_gang_tree_assemble_done(zio_t
*zio
)
2068 zio_t
*gio
= zio
->io_gang_leader
;
2069 zio_gang_node_t
*gn
= zio
->io_private
;
2070 blkptr_t
*bp
= zio
->io_bp
;
2072 ASSERT(gio
== zio_unique_parent(zio
));
2073 ASSERT(zio
->io_child_count
== 0);
2078 /* this ABD was created from a linear buf in zio_gang_tree_assemble */
2079 if (BP_SHOULD_BYTESWAP(bp
))
2080 byteswap_uint64_array(abd_to_buf(zio
->io_abd
), zio
->io_size
);
2082 ASSERT3P(abd_to_buf(zio
->io_abd
), ==, gn
->gn_gbh
);
2083 ASSERT(zio
->io_size
== SPA_GANGBLOCKSIZE
);
2084 ASSERT(gn
->gn_gbh
->zg_tail
.zec_magic
== ZEC_MAGIC
);
2086 abd_put(zio
->io_abd
);
2088 for (int g
= 0; g
< SPA_GBH_NBLKPTRS
; g
++) {
2089 blkptr_t
*gbp
= &gn
->gn_gbh
->zg_blkptr
[g
];
2090 if (!BP_IS_GANG(gbp
))
2092 zio_gang_tree_assemble(gio
, gbp
, &gn
->gn_child
[g
]);
2097 zio_gang_tree_issue(zio_t
*pio
, zio_gang_node_t
*gn
, blkptr_t
*bp
, abd_t
*data
,
2100 zio_t
*gio
= pio
->io_gang_leader
;
2103 ASSERT(BP_IS_GANG(bp
) == !!gn
);
2104 ASSERT(BP_GET_CHECKSUM(bp
) == BP_GET_CHECKSUM(gio
->io_bp
));
2105 ASSERT(BP_GET_LSIZE(bp
) == BP_GET_PSIZE(bp
) || gn
== gio
->io_gang_tree
);
2108 * If you're a gang header, your data is in gn->gn_gbh.
2109 * If you're a gang member, your data is in 'data' and gn == NULL.
2111 zio
= zio_gang_issue_func
[gio
->io_type
](pio
, bp
, gn
, data
, offset
);
2114 ASSERT(gn
->gn_gbh
->zg_tail
.zec_magic
== ZEC_MAGIC
);
2116 for (int g
= 0; g
< SPA_GBH_NBLKPTRS
; g
++) {
2117 blkptr_t
*gbp
= &gn
->gn_gbh
->zg_blkptr
[g
];
2118 if (BP_IS_HOLE(gbp
))
2120 zio_gang_tree_issue(zio
, gn
->gn_child
[g
], gbp
, data
,
2122 offset
+= BP_GET_PSIZE(gbp
);
2126 if (gn
== gio
->io_gang_tree
)
2127 ASSERT3U(gio
->io_size
, ==, offset
);
2134 zio_gang_assemble(zio_t
*zio
)
2136 blkptr_t
*bp
= zio
->io_bp
;
2138 ASSERT(BP_IS_GANG(bp
) && zio
->io_gang_leader
== NULL
);
2139 ASSERT(zio
->io_child_type
> ZIO_CHILD_GANG
);
2141 zio
->io_gang_leader
= zio
;
2143 zio_gang_tree_assemble(zio
, bp
, &zio
->io_gang_tree
);
2145 return (ZIO_PIPELINE_CONTINUE
);
2149 zio_gang_issue(zio_t
*zio
)
2151 blkptr_t
*bp
= zio
->io_bp
;
2153 if (zio_wait_for_children(zio
, ZIO_CHILD_GANG_BIT
, ZIO_WAIT_DONE
)) {
2154 return (ZIO_PIPELINE_STOP
);
2157 ASSERT(BP_IS_GANG(bp
) && zio
->io_gang_leader
== zio
);
2158 ASSERT(zio
->io_child_type
> ZIO_CHILD_GANG
);
2160 if (zio
->io_child_error
[ZIO_CHILD_GANG
] == 0)
2161 zio_gang_tree_issue(zio
, zio
->io_gang_tree
, bp
, zio
->io_abd
,
2164 zio_gang_tree_free(&zio
->io_gang_tree
);
2166 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
2168 return (ZIO_PIPELINE_CONTINUE
);
2172 zio_write_gang_member_ready(zio_t
*zio
)
2174 zio_t
*pio
= zio_unique_parent(zio
);
2175 zio_t
*gio
= zio
->io_gang_leader
;
2176 dva_t
*cdva
= zio
->io_bp
->blk_dva
;
2177 dva_t
*pdva
= pio
->io_bp
->blk_dva
;
2180 if (BP_IS_HOLE(zio
->io_bp
))
2183 ASSERT(BP_IS_HOLE(&zio
->io_bp_orig
));
2185 ASSERT(zio
->io_child_type
== ZIO_CHILD_GANG
);
2186 ASSERT3U(zio
->io_prop
.zp_copies
, ==, gio
->io_prop
.zp_copies
);
2187 ASSERT3U(zio
->io_prop
.zp_copies
, <=, BP_GET_NDVAS(zio
->io_bp
));
2188 ASSERT3U(pio
->io_prop
.zp_copies
, <=, BP_GET_NDVAS(pio
->io_bp
));
2189 ASSERT3U(BP_GET_NDVAS(zio
->io_bp
), <=, BP_GET_NDVAS(pio
->io_bp
));
2191 mutex_enter(&pio
->io_lock
);
2192 for (int d
= 0; d
< BP_GET_NDVAS(zio
->io_bp
); d
++) {
2193 ASSERT(DVA_GET_GANG(&pdva
[d
]));
2194 asize
= DVA_GET_ASIZE(&pdva
[d
]);
2195 asize
+= DVA_GET_ASIZE(&cdva
[d
]);
2196 DVA_SET_ASIZE(&pdva
[d
], asize
);
2198 mutex_exit(&pio
->io_lock
);
2202 zio_write_gang_done(zio_t
*zio
)
2204 abd_put(zio
->io_abd
);
2208 zio_write_gang_block(zio_t
*pio
)
2210 spa_t
*spa
= pio
->io_spa
;
2211 metaslab_class_t
*mc
= spa_normal_class(spa
);
2212 blkptr_t
*bp
= pio
->io_bp
;
2213 zio_t
*gio
= pio
->io_gang_leader
;
2215 zio_gang_node_t
*gn
, **gnpp
;
2216 zio_gbh_phys_t
*gbh
;
2218 uint64_t txg
= pio
->io_txg
;
2219 uint64_t resid
= pio
->io_size
;
2221 int copies
= gio
->io_prop
.zp_copies
;
2222 int gbh_copies
= MIN(copies
+ 1, spa_max_replication(spa
));
2226 int flags
= METASLAB_HINTBP_FAVOR
| METASLAB_GANG_HEADER
;
2227 if (pio
->io_flags
& ZIO_FLAG_IO_ALLOCATING
) {
2228 ASSERT(pio
->io_priority
== ZIO_PRIORITY_ASYNC_WRITE
);
2229 ASSERT(!(pio
->io_flags
& ZIO_FLAG_NODATA
));
2231 flags
|= METASLAB_ASYNC_ALLOC
;
2232 VERIFY(refcount_held(&mc
->mc_alloc_slots
, pio
));
2235 * The logical zio has already placed a reservation for
2236 * 'copies' allocation slots but gang blocks may require
2237 * additional copies. These additional copies
2238 * (i.e. gbh_copies - copies) are guaranteed to succeed
2239 * since metaslab_class_throttle_reserve() always allows
2240 * additional reservations for gang blocks.
2242 VERIFY(metaslab_class_throttle_reserve(mc
, gbh_copies
- copies
,
2246 error
= metaslab_alloc(spa
, mc
, SPA_GANGBLOCKSIZE
,
2247 bp
, gbh_copies
, txg
, pio
== gio
? NULL
: gio
->io_bp
, flags
,
2248 &pio
->io_alloc_list
, pio
);
2250 if (pio
->io_flags
& ZIO_FLAG_IO_ALLOCATING
) {
2251 ASSERT(pio
->io_priority
== ZIO_PRIORITY_ASYNC_WRITE
);
2252 ASSERT(!(pio
->io_flags
& ZIO_FLAG_NODATA
));
2255 * If we failed to allocate the gang block header then
2256 * we remove any additional allocation reservations that
2257 * we placed here. The original reservation will
2258 * be removed when the logical I/O goes to the ready
2261 metaslab_class_throttle_unreserve(mc
,
2262 gbh_copies
- copies
, pio
);
2264 pio
->io_error
= error
;
2265 return (ZIO_PIPELINE_CONTINUE
);
2269 gnpp
= &gio
->io_gang_tree
;
2271 gnpp
= pio
->io_private
;
2272 ASSERT(pio
->io_ready
== zio_write_gang_member_ready
);
2275 gn
= zio_gang_node_alloc(gnpp
);
2277 bzero(gbh
, SPA_GANGBLOCKSIZE
);
2278 gbh_abd
= abd_get_from_buf(gbh
, SPA_GANGBLOCKSIZE
);
2281 * Create the gang header.
2283 zio
= zio_rewrite(pio
, spa
, txg
, bp
, gbh_abd
, SPA_GANGBLOCKSIZE
,
2284 zio_write_gang_done
, NULL
, pio
->io_priority
,
2285 ZIO_GANG_CHILD_FLAGS(pio
), &pio
->io_bookmark
);
2288 * Create and nowait the gang children.
2290 for (int g
= 0; resid
!= 0; resid
-= lsize
, g
++) {
2291 lsize
= P2ROUNDUP(resid
/ (SPA_GBH_NBLKPTRS
- g
),
2293 ASSERT(lsize
>= SPA_MINBLOCKSIZE
&& lsize
<= resid
);
2295 zp
.zp_checksum
= gio
->io_prop
.zp_checksum
;
2296 zp
.zp_compress
= ZIO_COMPRESS_OFF
;
2297 zp
.zp_type
= DMU_OT_NONE
;
2299 zp
.zp_copies
= gio
->io_prop
.zp_copies
;
2300 zp
.zp_dedup
= B_FALSE
;
2301 zp
.zp_dedup_verify
= B_FALSE
;
2302 zp
.zp_nopwrite
= B_FALSE
;
2304 zio_t
*cio
= zio_write(zio
, spa
, txg
, &gbh
->zg_blkptr
[g
],
2305 abd_get_offset(pio
->io_abd
, pio
->io_size
- resid
), lsize
,
2306 lsize
, &zp
, zio_write_gang_member_ready
, NULL
, NULL
,
2307 zio_write_gang_done
, &gn
->gn_child
[g
], pio
->io_priority
,
2308 ZIO_GANG_CHILD_FLAGS(pio
), &pio
->io_bookmark
);
2310 if (pio
->io_flags
& ZIO_FLAG_IO_ALLOCATING
) {
2311 ASSERT(pio
->io_priority
== ZIO_PRIORITY_ASYNC_WRITE
);
2312 ASSERT(!(pio
->io_flags
& ZIO_FLAG_NODATA
));
2315 * Gang children won't throttle but we should
2316 * account for their work, so reserve an allocation
2317 * slot for them here.
2319 VERIFY(metaslab_class_throttle_reserve(mc
,
2320 zp
.zp_copies
, cio
, flags
));
2326 * Set pio's pipeline to just wait for zio to finish.
2328 pio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
2332 return (ZIO_PIPELINE_CONTINUE
);
2336 * The zio_nop_write stage in the pipeline determines if allocating a
2337 * new bp is necessary. The nopwrite feature can handle writes in
2338 * either syncing or open context (i.e. zil writes) and as a result is
2339 * mutually exclusive with dedup.
2341 * By leveraging a cryptographically secure checksum, such as SHA256, we
2342 * can compare the checksums of the new data and the old to determine if
2343 * allocating a new block is required. Note that our requirements for
2344 * cryptographic strength are fairly weak: there can't be any accidental
2345 * hash collisions, but we don't need to be secure against intentional
2346 * (malicious) collisions. To trigger a nopwrite, you have to be able
2347 * to write the file to begin with, and triggering an incorrect (hash
2348 * collision) nopwrite is no worse than simply writing to the file.
2349 * That said, there are no known attacks against the checksum algorithms
2350 * used for nopwrite, assuming that the salt and the checksums
2351 * themselves remain secret.
2354 zio_nop_write(zio_t
*zio
)
2356 blkptr_t
*bp
= zio
->io_bp
;
2357 blkptr_t
*bp_orig
= &zio
->io_bp_orig
;
2358 zio_prop_t
*zp
= &zio
->io_prop
;
2360 ASSERT(BP_GET_LEVEL(bp
) == 0);
2361 ASSERT(!(zio
->io_flags
& ZIO_FLAG_IO_REWRITE
));
2362 ASSERT(zp
->zp_nopwrite
);
2363 ASSERT(!zp
->zp_dedup
);
2364 ASSERT(zio
->io_bp_override
== NULL
);
2365 ASSERT(IO_IS_ALLOCATING(zio
));
2368 * Check to see if the original bp and the new bp have matching
2369 * characteristics (i.e. same checksum, compression algorithms, etc).
2370 * If they don't then just continue with the pipeline which will
2371 * allocate a new bp.
2373 if (BP_IS_HOLE(bp_orig
) ||
2374 !(zio_checksum_table
[BP_GET_CHECKSUM(bp
)].ci_flags
&
2375 ZCHECKSUM_FLAG_NOPWRITE
) ||
2376 BP_GET_CHECKSUM(bp
) != BP_GET_CHECKSUM(bp_orig
) ||
2377 BP_GET_COMPRESS(bp
) != BP_GET_COMPRESS(bp_orig
) ||
2378 BP_GET_DEDUP(bp
) != BP_GET_DEDUP(bp_orig
) ||
2379 zp
->zp_copies
!= BP_GET_NDVAS(bp_orig
))
2380 return (ZIO_PIPELINE_CONTINUE
);
2383 * If the checksums match then reset the pipeline so that we
2384 * avoid allocating a new bp and issuing any I/O.
2386 if (ZIO_CHECKSUM_EQUAL(bp
->blk_cksum
, bp_orig
->blk_cksum
)) {
2387 ASSERT(zio_checksum_table
[zp
->zp_checksum
].ci_flags
&
2388 ZCHECKSUM_FLAG_NOPWRITE
);
2389 ASSERT3U(BP_GET_PSIZE(bp
), ==, BP_GET_PSIZE(bp_orig
));
2390 ASSERT3U(BP_GET_LSIZE(bp
), ==, BP_GET_LSIZE(bp_orig
));
2391 ASSERT(zp
->zp_compress
!= ZIO_COMPRESS_OFF
);
2392 ASSERT(bcmp(&bp
->blk_prop
, &bp_orig
->blk_prop
,
2393 sizeof (uint64_t)) == 0);
2396 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
2397 zio
->io_flags
|= ZIO_FLAG_NOPWRITE
;
2400 return (ZIO_PIPELINE_CONTINUE
);
2404 * ==========================================================================
2406 * ==========================================================================
2409 zio_ddt_child_read_done(zio_t
*zio
)
2411 blkptr_t
*bp
= zio
->io_bp
;
2412 ddt_entry_t
*dde
= zio
->io_private
;
2414 zio_t
*pio
= zio_unique_parent(zio
);
2416 mutex_enter(&pio
->io_lock
);
2417 ddp
= ddt_phys_select(dde
, bp
);
2418 if (zio
->io_error
== 0)
2419 ddt_phys_clear(ddp
); /* this ddp doesn't need repair */
2421 if (zio
->io_error
== 0 && dde
->dde_repair_abd
== NULL
)
2422 dde
->dde_repair_abd
= zio
->io_abd
;
2424 abd_free(zio
->io_abd
);
2425 mutex_exit(&pio
->io_lock
);
2429 zio_ddt_read_start(zio_t
*zio
)
2431 blkptr_t
*bp
= zio
->io_bp
;
2433 ASSERT(BP_GET_DEDUP(bp
));
2434 ASSERT(BP_GET_PSIZE(bp
) == zio
->io_size
);
2435 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
2437 if (zio
->io_child_error
[ZIO_CHILD_DDT
]) {
2438 ddt_t
*ddt
= ddt_select(zio
->io_spa
, bp
);
2439 ddt_entry_t
*dde
= ddt_repair_start(ddt
, bp
);
2440 ddt_phys_t
*ddp
= dde
->dde_phys
;
2441 ddt_phys_t
*ddp_self
= ddt_phys_select(dde
, bp
);
2444 ASSERT(zio
->io_vsd
== NULL
);
2447 if (ddp_self
== NULL
)
2448 return (ZIO_PIPELINE_CONTINUE
);
2450 for (int p
= 0; p
< DDT_PHYS_TYPES
; p
++, ddp
++) {
2451 if (ddp
->ddp_phys_birth
== 0 || ddp
== ddp_self
)
2453 ddt_bp_create(ddt
->ddt_checksum
, &dde
->dde_key
, ddp
,
2455 zio_nowait(zio_read(zio
, zio
->io_spa
, &blk
,
2456 abd_alloc_for_io(zio
->io_size
, B_TRUE
),
2457 zio
->io_size
, zio_ddt_child_read_done
, dde
,
2458 zio
->io_priority
, ZIO_DDT_CHILD_FLAGS(zio
) |
2459 ZIO_FLAG_DONT_PROPAGATE
, &zio
->io_bookmark
));
2461 return (ZIO_PIPELINE_CONTINUE
);
2464 zio_nowait(zio_read(zio
, zio
->io_spa
, bp
,
2465 zio
->io_abd
, zio
->io_size
, NULL
, NULL
, zio
->io_priority
,
2466 ZIO_DDT_CHILD_FLAGS(zio
), &zio
->io_bookmark
));
2468 return (ZIO_PIPELINE_CONTINUE
);
2472 zio_ddt_read_done(zio_t
*zio
)
2474 blkptr_t
*bp
= zio
->io_bp
;
2476 if (zio_wait_for_children(zio
, ZIO_CHILD_DDT_BIT
, ZIO_WAIT_DONE
)) {
2477 return (ZIO_PIPELINE_STOP
);
2480 ASSERT(BP_GET_DEDUP(bp
));
2481 ASSERT(BP_GET_PSIZE(bp
) == zio
->io_size
);
2482 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
2484 if (zio
->io_child_error
[ZIO_CHILD_DDT
]) {
2485 ddt_t
*ddt
= ddt_select(zio
->io_spa
, bp
);
2486 ddt_entry_t
*dde
= zio
->io_vsd
;
2488 ASSERT(spa_load_state(zio
->io_spa
) != SPA_LOAD_NONE
);
2489 return (ZIO_PIPELINE_CONTINUE
);
2492 zio
->io_stage
= ZIO_STAGE_DDT_READ_START
>> 1;
2493 zio_taskq_dispatch(zio
, ZIO_TASKQ_ISSUE
, B_FALSE
);
2494 return (ZIO_PIPELINE_STOP
);
2496 if (dde
->dde_repair_abd
!= NULL
) {
2497 abd_copy(zio
->io_abd
, dde
->dde_repair_abd
,
2499 zio
->io_child_error
[ZIO_CHILD_DDT
] = 0;
2501 ddt_repair_done(ddt
, dde
);
2505 ASSERT(zio
->io_vsd
== NULL
);
2507 return (ZIO_PIPELINE_CONTINUE
);
2511 zio_ddt_collision(zio_t
*zio
, ddt_t
*ddt
, ddt_entry_t
*dde
)
2513 spa_t
*spa
= zio
->io_spa
;
2514 boolean_t do_raw
= (zio
->io_flags
& ZIO_FLAG_RAW
);
2516 /* We should never get a raw, override zio */
2517 ASSERT(!(zio
->io_bp_override
&& do_raw
));
2520 * Note: we compare the original data, not the transformed data,
2521 * because when zio->io_bp is an override bp, we will not have
2522 * pushed the I/O transforms. That's an important optimization
2523 * because otherwise we'd compress/encrypt all dmu_sync() data twice.
2525 for (int p
= DDT_PHYS_SINGLE
; p
<= DDT_PHYS_TRIPLE
; p
++) {
2526 zio_t
*lio
= dde
->dde_lead_zio
[p
];
2529 return (lio
->io_orig_size
!= zio
->io_orig_size
||
2530 abd_cmp(zio
->io_orig_abd
, lio
->io_orig_abd
,
2531 zio
->io_orig_size
) != 0);
2535 for (int p
= DDT_PHYS_SINGLE
; p
<= DDT_PHYS_TRIPLE
; p
++) {
2536 ddt_phys_t
*ddp
= &dde
->dde_phys
[p
];
2538 if (ddp
->ddp_phys_birth
!= 0) {
2539 arc_buf_t
*abuf
= NULL
;
2540 arc_flags_t aflags
= ARC_FLAG_WAIT
;
2541 int zio_flags
= ZIO_FLAG_CANFAIL
| ZIO_FLAG_SPECULATIVE
;
2542 blkptr_t blk
= *zio
->io_bp
;
2545 ddt_bp_fill(ddp
, &blk
, ddp
->ddp_phys_birth
);
2550 * Intuitively, it would make more sense to compare
2551 * io_abd than io_orig_abd in the raw case since you
2552 * don't want to look at any transformations that have
2553 * happened to the data. However, for raw I/Os the
2554 * data will actually be the same in io_abd and
2555 * io_orig_abd, so all we have to do is issue this as
2559 zio_flags
|= ZIO_FLAG_RAW
;
2560 ASSERT3U(zio
->io_size
, ==, zio
->io_orig_size
);
2561 ASSERT0(abd_cmp(zio
->io_abd
, zio
->io_orig_abd
,
2563 ASSERT3P(zio
->io_transform_stack
, ==, NULL
);
2566 error
= arc_read(NULL
, spa
, &blk
,
2567 arc_getbuf_func
, &abuf
, ZIO_PRIORITY_SYNC_READ
,
2568 zio_flags
, &aflags
, &zio
->io_bookmark
);
2571 if (arc_buf_size(abuf
) != zio
->io_orig_size
||
2572 abd_cmp_buf(zio
->io_orig_abd
, abuf
->b_data
,
2573 zio
->io_orig_size
) != 0)
2574 error
= SET_ERROR(EEXIST
);
2575 arc_buf_destroy(abuf
, &abuf
);
2579 return (error
!= 0);
2587 zio_ddt_child_write_ready(zio_t
*zio
)
2589 int p
= zio
->io_prop
.zp_copies
;
2590 ddt_t
*ddt
= ddt_select(zio
->io_spa
, zio
->io_bp
);
2591 ddt_entry_t
*dde
= zio
->io_private
;
2592 ddt_phys_t
*ddp
= &dde
->dde_phys
[p
];
2600 ASSERT(dde
->dde_lead_zio
[p
] == zio
);
2602 ddt_phys_fill(ddp
, zio
->io_bp
);
2604 zio_link_t
*zl
= NULL
;
2605 while ((pio
= zio_walk_parents(zio
, &zl
)) != NULL
)
2606 ddt_bp_fill(ddp
, pio
->io_bp
, zio
->io_txg
);
2612 zio_ddt_child_write_done(zio_t
*zio
)
2614 int p
= zio
->io_prop
.zp_copies
;
2615 ddt_t
*ddt
= ddt_select(zio
->io_spa
, zio
->io_bp
);
2616 ddt_entry_t
*dde
= zio
->io_private
;
2617 ddt_phys_t
*ddp
= &dde
->dde_phys
[p
];
2621 ASSERT(ddp
->ddp_refcnt
== 0);
2622 ASSERT(dde
->dde_lead_zio
[p
] == zio
);
2623 dde
->dde_lead_zio
[p
] = NULL
;
2625 if (zio
->io_error
== 0) {
2626 zio_link_t
*zl
= NULL
;
2627 while (zio_walk_parents(zio
, &zl
) != NULL
)
2628 ddt_phys_addref(ddp
);
2630 ddt_phys_clear(ddp
);
2637 zio_ddt_ditto_write_done(zio_t
*zio
)
2639 int p
= DDT_PHYS_DITTO
;
2640 zio_prop_t
*zp
= &zio
->io_prop
;
2641 blkptr_t
*bp
= zio
->io_bp
;
2642 ddt_t
*ddt
= ddt_select(zio
->io_spa
, bp
);
2643 ddt_entry_t
*dde
= zio
->io_private
;
2644 ddt_phys_t
*ddp
= &dde
->dde_phys
[p
];
2645 ddt_key_t
*ddk
= &dde
->dde_key
;
2649 ASSERT(ddp
->ddp_refcnt
== 0);
2650 ASSERT(dde
->dde_lead_zio
[p
] == zio
);
2651 dde
->dde_lead_zio
[p
] = NULL
;
2653 if (zio
->io_error
== 0) {
2654 ASSERT(ZIO_CHECKSUM_EQUAL(bp
->blk_cksum
, ddk
->ddk_cksum
));
2655 ASSERT(zp
->zp_copies
< SPA_DVAS_PER_BP
);
2656 ASSERT(zp
->zp_copies
== BP_GET_NDVAS(bp
) - BP_IS_GANG(bp
));
2657 if (ddp
->ddp_phys_birth
!= 0)
2658 ddt_phys_free(ddt
, ddk
, ddp
, zio
->io_txg
);
2659 ddt_phys_fill(ddp
, bp
);
2666 zio_ddt_write(zio_t
*zio
)
2668 spa_t
*spa
= zio
->io_spa
;
2669 blkptr_t
*bp
= zio
->io_bp
;
2670 uint64_t txg
= zio
->io_txg
;
2671 zio_prop_t
*zp
= &zio
->io_prop
;
2672 int p
= zp
->zp_copies
;
2676 ddt_t
*ddt
= ddt_select(spa
, bp
);
2680 ASSERT(BP_GET_DEDUP(bp
));
2681 ASSERT(BP_GET_CHECKSUM(bp
) == zp
->zp_checksum
);
2682 ASSERT(BP_IS_HOLE(bp
) || zio
->io_bp_override
);
2683 ASSERT(!(zio
->io_bp_override
&& (zio
->io_flags
& ZIO_FLAG_RAW
)));
2686 dde
= ddt_lookup(ddt
, bp
, B_TRUE
);
2687 ddp
= &dde
->dde_phys
[p
];
2689 if (zp
->zp_dedup_verify
&& zio_ddt_collision(zio
, ddt
, dde
)) {
2691 * If we're using a weak checksum, upgrade to a strong checksum
2692 * and try again. If we're already using a strong checksum,
2693 * we can't resolve it, so just convert to an ordinary write.
2694 * (And automatically e-mail a paper to Nature?)
2696 if (!(zio_checksum_table
[zp
->zp_checksum
].ci_flags
&
2697 ZCHECKSUM_FLAG_DEDUP
)) {
2698 zp
->zp_checksum
= spa_dedup_checksum(spa
);
2699 zio_pop_transforms(zio
);
2700 zio
->io_stage
= ZIO_STAGE_OPEN
;
2703 zp
->zp_dedup
= B_FALSE
;
2704 BP_SET_DEDUP(bp
, B_FALSE
);
2706 ASSERT(!BP_GET_DEDUP(bp
));
2707 zio
->io_pipeline
= ZIO_WRITE_PIPELINE
;
2709 return (ZIO_PIPELINE_CONTINUE
);
2712 ditto_copies
= ddt_ditto_copies_needed(ddt
, dde
, ddp
);
2713 ASSERT(ditto_copies
< SPA_DVAS_PER_BP
);
2715 if (ditto_copies
> ddt_ditto_copies_present(dde
) &&
2716 dde
->dde_lead_zio
[DDT_PHYS_DITTO
] == NULL
) {
2717 zio_prop_t czp
= *zp
;
2719 czp
.zp_copies
= ditto_copies
;
2722 * If we arrived here with an override bp, we won't have run
2723 * the transform stack, so we won't have the data we need to
2724 * generate a child i/o. So, toss the override bp and restart.
2725 * This is safe, because using the override bp is just an
2726 * optimization; and it's rare, so the cost doesn't matter.
2728 if (zio
->io_bp_override
) {
2729 zio_pop_transforms(zio
);
2730 zio
->io_stage
= ZIO_STAGE_OPEN
;
2731 zio
->io_pipeline
= ZIO_WRITE_PIPELINE
;
2732 zio
->io_bp_override
= NULL
;
2735 return (ZIO_PIPELINE_CONTINUE
);
2738 dio
= zio_write(zio
, spa
, txg
, bp
, zio
->io_orig_abd
,
2739 zio
->io_orig_size
, zio
->io_orig_size
, &czp
, NULL
, NULL
,
2740 NULL
, zio_ddt_ditto_write_done
, dde
, zio
->io_priority
,
2741 ZIO_DDT_CHILD_FLAGS(zio
), &zio
->io_bookmark
);
2743 zio_push_transform(dio
, zio
->io_abd
, zio
->io_size
, 0, NULL
);
2744 dde
->dde_lead_zio
[DDT_PHYS_DITTO
] = dio
;
2747 if (ddp
->ddp_phys_birth
!= 0 || dde
->dde_lead_zio
[p
] != NULL
) {
2748 if (ddp
->ddp_phys_birth
!= 0)
2749 ddt_bp_fill(ddp
, bp
, txg
);
2750 if (dde
->dde_lead_zio
[p
] != NULL
)
2751 zio_add_child(zio
, dde
->dde_lead_zio
[p
]);
2753 ddt_phys_addref(ddp
);
2754 } else if (zio
->io_bp_override
) {
2755 ASSERT(bp
->blk_birth
== txg
);
2756 ASSERT(BP_EQUAL(bp
, zio
->io_bp_override
));
2757 ddt_phys_fill(ddp
, bp
);
2758 ddt_phys_addref(ddp
);
2760 cio
= zio_write(zio
, spa
, txg
, bp
, zio
->io_orig_abd
,
2761 zio
->io_orig_size
, zio
->io_orig_size
, zp
,
2762 zio_ddt_child_write_ready
, NULL
, NULL
,
2763 zio_ddt_child_write_done
, dde
, zio
->io_priority
,
2764 ZIO_DDT_CHILD_FLAGS(zio
), &zio
->io_bookmark
);
2766 zio_push_transform(cio
, zio
->io_abd
, zio
->io_size
, 0, NULL
);
2767 dde
->dde_lead_zio
[p
] = cio
;
2777 return (ZIO_PIPELINE_CONTINUE
);
2780 ddt_entry_t
*freedde
; /* for debugging */
2783 zio_ddt_free(zio_t
*zio
)
2785 spa_t
*spa
= zio
->io_spa
;
2786 blkptr_t
*bp
= zio
->io_bp
;
2787 ddt_t
*ddt
= ddt_select(spa
, bp
);
2791 ASSERT(BP_GET_DEDUP(bp
));
2792 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
2795 freedde
= dde
= ddt_lookup(ddt
, bp
, B_TRUE
);
2796 ddp
= ddt_phys_select(dde
, bp
);
2797 ddt_phys_decref(ddp
);
2800 return (ZIO_PIPELINE_CONTINUE
);
2804 * ==========================================================================
2805 * Allocate and free blocks
2806 * ==========================================================================
2810 zio_io_to_allocate(spa_t
*spa
)
2814 ASSERT(MUTEX_HELD(&spa
->spa_alloc_lock
));
2816 zio
= avl_first(&spa
->spa_alloc_tree
);
2820 ASSERT(IO_IS_ALLOCATING(zio
));
2823 * Try to place a reservation for this zio. If we're unable to
2824 * reserve then we throttle.
2826 if (!metaslab_class_throttle_reserve(spa_normal_class(spa
),
2827 zio
->io_prop
.zp_copies
, zio
, 0)) {
2831 avl_remove(&spa
->spa_alloc_tree
, zio
);
2832 ASSERT3U(zio
->io_stage
, <, ZIO_STAGE_DVA_ALLOCATE
);
2838 zio_dva_throttle(zio_t
*zio
)
2840 spa_t
*spa
= zio
->io_spa
;
2843 if (zio
->io_priority
== ZIO_PRIORITY_SYNC_WRITE
||
2844 !spa_normal_class(zio
->io_spa
)->mc_alloc_throttle_enabled
||
2845 zio
->io_child_type
== ZIO_CHILD_GANG
||
2846 zio
->io_flags
& ZIO_FLAG_NODATA
) {
2847 return (ZIO_PIPELINE_CONTINUE
);
2850 ASSERT(zio
->io_child_type
> ZIO_CHILD_GANG
);
2852 ASSERT3U(zio
->io_queued_timestamp
, >, 0);
2853 ASSERT(zio
->io_stage
== ZIO_STAGE_DVA_THROTTLE
);
2855 mutex_enter(&spa
->spa_alloc_lock
);
2857 ASSERT(zio
->io_type
== ZIO_TYPE_WRITE
);
2858 avl_add(&spa
->spa_alloc_tree
, zio
);
2860 nio
= zio_io_to_allocate(zio
->io_spa
);
2861 mutex_exit(&spa
->spa_alloc_lock
);
2864 return (ZIO_PIPELINE_CONTINUE
);
2867 ASSERT(nio
->io_stage
== ZIO_STAGE_DVA_THROTTLE
);
2869 * We are passing control to a new zio so make sure that
2870 * it is processed by a different thread. We do this to
2871 * avoid stack overflows that can occur when parents are
2872 * throttled and children are making progress. We allow
2873 * it to go to the head of the taskq since it's already
2876 zio_taskq_dispatch(nio
, ZIO_TASKQ_ISSUE
, B_TRUE
);
2878 return (ZIO_PIPELINE_STOP
);
2882 zio_allocate_dispatch(spa_t
*spa
)
2886 mutex_enter(&spa
->spa_alloc_lock
);
2887 zio
= zio_io_to_allocate(spa
);
2888 mutex_exit(&spa
->spa_alloc_lock
);
2892 ASSERT3U(zio
->io_stage
, ==, ZIO_STAGE_DVA_THROTTLE
);
2893 ASSERT0(zio
->io_error
);
2894 zio_taskq_dispatch(zio
, ZIO_TASKQ_ISSUE
, B_TRUE
);
2898 zio_dva_allocate(zio_t
*zio
)
2900 spa_t
*spa
= zio
->io_spa
;
2901 metaslab_class_t
*mc
= spa_normal_class(spa
);
2902 blkptr_t
*bp
= zio
->io_bp
;
2906 if (zio
->io_gang_leader
== NULL
) {
2907 ASSERT(zio
->io_child_type
> ZIO_CHILD_GANG
);
2908 zio
->io_gang_leader
= zio
;
2911 ASSERT(BP_IS_HOLE(bp
));
2912 ASSERT0(BP_GET_NDVAS(bp
));
2913 ASSERT3U(zio
->io_prop
.zp_copies
, >, 0);
2914 ASSERT3U(zio
->io_prop
.zp_copies
, <=, spa_max_replication(spa
));
2915 ASSERT3U(zio
->io_size
, ==, BP_GET_PSIZE(bp
));
2917 if (zio
->io_flags
& ZIO_FLAG_NODATA
) {
2918 flags
|= METASLAB_DONT_THROTTLE
;
2920 if (zio
->io_flags
& ZIO_FLAG_GANG_CHILD
) {
2921 flags
|= METASLAB_GANG_CHILD
;
2923 if (zio
->io_priority
== ZIO_PRIORITY_ASYNC_WRITE
) {
2924 flags
|= METASLAB_ASYNC_ALLOC
;
2927 error
= metaslab_alloc(spa
, mc
, zio
->io_size
, bp
,
2928 zio
->io_prop
.zp_copies
, zio
->io_txg
, NULL
, flags
,
2929 &zio
->io_alloc_list
, zio
);
2932 spa_dbgmsg(spa
, "%s: metaslab allocation failure: zio %p, "
2933 "size %llu, error %d", spa_name(spa
), zio
, zio
->io_size
,
2935 if (error
== ENOSPC
&& zio
->io_size
> SPA_MINBLOCKSIZE
)
2936 return (zio_write_gang_block(zio
));
2937 zio
->io_error
= error
;
2940 return (ZIO_PIPELINE_CONTINUE
);
2944 zio_dva_free(zio_t
*zio
)
2946 metaslab_free(zio
->io_spa
, zio
->io_bp
, zio
->io_txg
, B_FALSE
);
2948 return (ZIO_PIPELINE_CONTINUE
);
2952 zio_dva_claim(zio_t
*zio
)
2956 error
= metaslab_claim(zio
->io_spa
, zio
->io_bp
, zio
->io_txg
);
2958 zio
->io_error
= error
;
2960 return (ZIO_PIPELINE_CONTINUE
);
2964 * Undo an allocation. This is used by zio_done() when an I/O fails
2965 * and we want to give back the block we just allocated.
2966 * This handles both normal blocks and gang blocks.
2969 zio_dva_unallocate(zio_t
*zio
, zio_gang_node_t
*gn
, blkptr_t
*bp
)
2971 ASSERT(bp
->blk_birth
== zio
->io_txg
|| BP_IS_HOLE(bp
));
2972 ASSERT(zio
->io_bp_override
== NULL
);
2974 if (!BP_IS_HOLE(bp
))
2975 metaslab_free(zio
->io_spa
, bp
, bp
->blk_birth
, B_TRUE
);
2978 for (int g
= 0; g
< SPA_GBH_NBLKPTRS
; g
++) {
2979 zio_dva_unallocate(zio
, gn
->gn_child
[g
],
2980 &gn
->gn_gbh
->zg_blkptr
[g
]);
2986 * Try to allocate an intent log block. Return 0 on success, errno on failure.
2989 zio_alloc_zil(spa_t
*spa
, uint64_t txg
, blkptr_t
*new_bp
, blkptr_t
*old_bp
,
2990 uint64_t size
, boolean_t
*slog
)
2993 zio_alloc_list_t io_alloc_list
;
2995 ASSERT(txg
> spa_syncing_txg(spa
));
2997 metaslab_trace_init(&io_alloc_list
);
2998 error
= metaslab_alloc(spa
, spa_log_class(spa
), size
, new_bp
, 1,
2999 txg
, old_bp
, METASLAB_HINTBP_AVOID
, &io_alloc_list
, NULL
);
3003 error
= metaslab_alloc(spa
, spa_normal_class(spa
), size
,
3004 new_bp
, 1, txg
, old_bp
, METASLAB_HINTBP_AVOID
,
3005 &io_alloc_list
, NULL
);
3009 metaslab_trace_fini(&io_alloc_list
);
3012 BP_SET_LSIZE(new_bp
, size
);
3013 BP_SET_PSIZE(new_bp
, size
);
3014 BP_SET_COMPRESS(new_bp
, ZIO_COMPRESS_OFF
);
3015 BP_SET_CHECKSUM(new_bp
,
3016 spa_version(spa
) >= SPA_VERSION_SLIM_ZIL
3017 ? ZIO_CHECKSUM_ZILOG2
: ZIO_CHECKSUM_ZILOG
);
3018 BP_SET_TYPE(new_bp
, DMU_OT_INTENT_LOG
);
3019 BP_SET_LEVEL(new_bp
, 0);
3020 BP_SET_DEDUP(new_bp
, 0);
3021 BP_SET_BYTEORDER(new_bp
, ZFS_HOST_BYTEORDER
);
3023 zfs_dbgmsg("%s: zil block allocation failure: "
3024 "size %llu, error %d", spa_name(spa
), size
, error
);
3031 * Free an intent log block.
3034 zio_free_zil(spa_t
*spa
, uint64_t txg
, blkptr_t
*bp
)
3036 ASSERT(BP_GET_TYPE(bp
) == DMU_OT_INTENT_LOG
);
3037 ASSERT(!BP_IS_GANG(bp
));
3039 zio_free(spa
, txg
, bp
);
3043 * ==========================================================================
3044 * Read and write to physical devices
3045 * ==========================================================================
3050 * Issue an I/O to the underlying vdev. Typically the issue pipeline
3051 * stops after this stage and will resume upon I/O completion.
3052 * However, there are instances where the vdev layer may need to
3053 * continue the pipeline when an I/O was not issued. Since the I/O
3054 * that was sent to the vdev layer might be different than the one
3055 * currently active in the pipeline (see vdev_queue_io()), we explicitly
3056 * force the underlying vdev layers to call either zio_execute() or
3057 * zio_interrupt() to ensure that the pipeline continues with the correct I/O.
3060 zio_vdev_io_start(zio_t
*zio
)
3062 vdev_t
*vd
= zio
->io_vd
;
3064 spa_t
*spa
= zio
->io_spa
;
3066 ASSERT(zio
->io_error
== 0);
3067 ASSERT(zio
->io_child_error
[ZIO_CHILD_VDEV
] == 0);
3070 if (!(zio
->io_flags
& ZIO_FLAG_CONFIG_WRITER
))
3071 spa_config_enter(spa
, SCL_ZIO
, zio
, RW_READER
);
3074 * The mirror_ops handle multiple DVAs in a single BP.
3076 vdev_mirror_ops
.vdev_op_io_start(zio
);
3077 return (ZIO_PIPELINE_STOP
);
3080 ASSERT3P(zio
->io_logical
, !=, zio
);
3081 if (zio
->io_type
== ZIO_TYPE_WRITE
) {
3082 ASSERT(spa
->spa_trust_config
);
3084 if (zio
->io_vd
->vdev_removing
) {
3085 ASSERT(zio
->io_flags
&
3086 (ZIO_FLAG_PHYSICAL
| ZIO_FLAG_SELF_HEAL
|
3087 ZIO_FLAG_INDUCE_DAMAGE
));
3092 * We keep track of time-sensitive I/Os so that the scan thread
3093 * can quickly react to certain workloads. In particular, we care
3094 * about non-scrubbing, top-level reads and writes with the following
3096 * - synchronous writes of user data to non-slog devices
3097 * - any reads of user data
3098 * When these conditions are met, adjust the timestamp of spa_last_io
3099 * which allows the scan thread to adjust its workload accordingly.
3101 if (!(zio
->io_flags
& ZIO_FLAG_SCAN_THREAD
) && zio
->io_bp
!= NULL
&&
3102 vd
== vd
->vdev_top
&& !vd
->vdev_islog
&&
3103 zio
->io_bookmark
.zb_objset
!= DMU_META_OBJSET
&&
3104 zio
->io_txg
!= spa_syncing_txg(spa
)) {
3105 uint64_t old
= spa
->spa_last_io
;
3106 uint64_t new = ddi_get_lbolt64();
3108 (void) atomic_cas_64(&spa
->spa_last_io
, old
, new);
3111 align
= 1ULL << vd
->vdev_top
->vdev_ashift
;
3113 if (!(zio
->io_flags
& ZIO_FLAG_PHYSICAL
) &&
3114 P2PHASE(zio
->io_size
, align
) != 0) {
3115 /* Transform logical writes to be a full physical block size. */
3116 uint64_t asize
= P2ROUNDUP(zio
->io_size
, align
);
3117 abd_t
*abuf
= abd_alloc_sametype(zio
->io_abd
, asize
);
3118 ASSERT(vd
== vd
->vdev_top
);
3119 if (zio
->io_type
== ZIO_TYPE_WRITE
) {
3120 abd_copy(abuf
, zio
->io_abd
, zio
->io_size
);
3121 abd_zero_off(abuf
, zio
->io_size
, asize
- zio
->io_size
);
3123 zio_push_transform(zio
, abuf
, asize
, asize
, zio_subblock
);
3127 * If this is not a physical io, make sure that it is properly aligned
3128 * before proceeding.
3130 if (!(zio
->io_flags
& ZIO_FLAG_PHYSICAL
)) {
3131 ASSERT0(P2PHASE(zio
->io_offset
, align
));
3132 ASSERT0(P2PHASE(zio
->io_size
, align
));
3135 * For physical writes, we allow 512b aligned writes and assume
3136 * the device will perform a read-modify-write as necessary.
3138 ASSERT0(P2PHASE(zio
->io_offset
, SPA_MINBLOCKSIZE
));
3139 ASSERT0(P2PHASE(zio
->io_size
, SPA_MINBLOCKSIZE
));
3142 VERIFY(zio
->io_type
!= ZIO_TYPE_WRITE
|| spa_writeable(spa
));
3145 * If this is a repair I/O, and there's no self-healing involved --
3146 * that is, we're just resilvering what we expect to resilver --
3147 * then don't do the I/O unless zio's txg is actually in vd's DTL.
3148 * This prevents spurious resilvering with nested replication.
3149 * For example, given a mirror of mirrors, (A+B)+(C+D), if only
3150 * A is out of date, we'll read from C+D, then use the data to
3151 * resilver A+B -- but we don't actually want to resilver B, just A.
3152 * The top-level mirror has no way to know this, so instead we just
3153 * discard unnecessary repairs as we work our way down the vdev tree.
3154 * The same logic applies to any form of nested replication:
3155 * ditto + mirror, RAID-Z + replacing, etc. This covers them all.
3157 if ((zio
->io_flags
& ZIO_FLAG_IO_REPAIR
) &&
3158 !(zio
->io_flags
& ZIO_FLAG_SELF_HEAL
) &&
3159 zio
->io_txg
!= 0 && /* not a delegated i/o */
3160 !vdev_dtl_contains(vd
, DTL_PARTIAL
, zio
->io_txg
, 1)) {
3161 ASSERT(zio
->io_type
== ZIO_TYPE_WRITE
);
3162 zio_vdev_io_bypass(zio
);
3163 return (ZIO_PIPELINE_CONTINUE
);
3166 if (vd
->vdev_ops
->vdev_op_leaf
&&
3167 (zio
->io_type
== ZIO_TYPE_READ
|| zio
->io_type
== ZIO_TYPE_WRITE
)) {
3169 if (zio
->io_type
== ZIO_TYPE_READ
&& vdev_cache_read(zio
))
3170 return (ZIO_PIPELINE_CONTINUE
);
3172 if ((zio
= vdev_queue_io(zio
)) == NULL
)
3173 return (ZIO_PIPELINE_STOP
);
3175 if (!vdev_accessible(vd
, zio
)) {
3176 zio
->io_error
= SET_ERROR(ENXIO
);
3178 return (ZIO_PIPELINE_STOP
);
3182 vd
->vdev_ops
->vdev_op_io_start(zio
);
3183 return (ZIO_PIPELINE_STOP
);
3187 zio_vdev_io_done(zio_t
*zio
)
3189 vdev_t
*vd
= zio
->io_vd
;
3190 vdev_ops_t
*ops
= vd
? vd
->vdev_ops
: &vdev_mirror_ops
;
3191 boolean_t unexpected_error
= B_FALSE
;
3193 if (zio_wait_for_children(zio
, ZIO_CHILD_VDEV_BIT
, ZIO_WAIT_DONE
)) {
3194 return (ZIO_PIPELINE_STOP
);
3197 ASSERT(zio
->io_type
== ZIO_TYPE_READ
|| zio
->io_type
== ZIO_TYPE_WRITE
);
3199 if (vd
!= NULL
&& vd
->vdev_ops
->vdev_op_leaf
) {
3201 vdev_queue_io_done(zio
);
3203 if (zio
->io_type
== ZIO_TYPE_WRITE
)
3204 vdev_cache_write(zio
);
3206 if (zio_injection_enabled
&& zio
->io_error
== 0)
3207 zio
->io_error
= zio_handle_device_injection(vd
,
3210 if (zio_injection_enabled
&& zio
->io_error
== 0)
3211 zio
->io_error
= zio_handle_label_injection(zio
, EIO
);
3213 if (zio
->io_error
) {
3214 if (!vdev_accessible(vd
, zio
)) {
3215 zio
->io_error
= SET_ERROR(ENXIO
);
3217 unexpected_error
= B_TRUE
;
3222 ops
->vdev_op_io_done(zio
);
3224 if (unexpected_error
)
3225 VERIFY(vdev_probe(vd
, zio
) == NULL
);
3227 return (ZIO_PIPELINE_CONTINUE
);
3231 * For non-raidz ZIOs, we can just copy aside the bad data read from the
3232 * disk, and use that to finish the checksum ereport later.
3235 zio_vsd_default_cksum_finish(zio_cksum_report_t
*zcr
,
3236 const void *good_buf
)
3238 /* no processing needed */
3239 zfs_ereport_finish_checksum(zcr
, good_buf
, zcr
->zcr_cbdata
, B_FALSE
);
3244 zio_vsd_default_cksum_report(zio_t
*zio
, zio_cksum_report_t
*zcr
, void *ignored
)
3246 void *buf
= zio_buf_alloc(zio
->io_size
);
3248 abd_copy_to_buf(buf
, zio
->io_abd
, zio
->io_size
);
3250 zcr
->zcr_cbinfo
= zio
->io_size
;
3251 zcr
->zcr_cbdata
= buf
;
3252 zcr
->zcr_finish
= zio_vsd_default_cksum_finish
;
3253 zcr
->zcr_free
= zio_buf_free
;
3257 zio_vdev_io_assess(zio_t
*zio
)
3259 vdev_t
*vd
= zio
->io_vd
;
3261 if (zio_wait_for_children(zio
, ZIO_CHILD_VDEV_BIT
, ZIO_WAIT_DONE
)) {
3262 return (ZIO_PIPELINE_STOP
);
3265 if (vd
== NULL
&& !(zio
->io_flags
& ZIO_FLAG_CONFIG_WRITER
))
3266 spa_config_exit(zio
->io_spa
, SCL_ZIO
, zio
);
3268 if (zio
->io_vsd
!= NULL
) {
3269 zio
->io_vsd_ops
->vsd_free(zio
);
3273 if (zio_injection_enabled
&& zio
->io_error
== 0)
3274 zio
->io_error
= zio_handle_fault_injection(zio
, EIO
);
3277 * If the I/O failed, determine whether we should attempt to retry it.
3279 * On retry, we cut in line in the issue queue, since we don't want
3280 * compression/checksumming/etc. work to prevent our (cheap) IO reissue.
3282 if (zio
->io_error
&& vd
== NULL
&&
3283 !(zio
->io_flags
& (ZIO_FLAG_DONT_RETRY
| ZIO_FLAG_IO_RETRY
))) {
3284 ASSERT(!(zio
->io_flags
& ZIO_FLAG_DONT_QUEUE
)); /* not a leaf */
3285 ASSERT(!(zio
->io_flags
& ZIO_FLAG_IO_BYPASS
)); /* not a leaf */
3287 zio
->io_flags
|= ZIO_FLAG_IO_RETRY
|
3288 ZIO_FLAG_DONT_CACHE
| ZIO_FLAG_DONT_AGGREGATE
;
3289 zio
->io_stage
= ZIO_STAGE_VDEV_IO_START
>> 1;
3290 zio_taskq_dispatch(zio
, ZIO_TASKQ_ISSUE
,
3291 zio_requeue_io_start_cut_in_line
);
3292 return (ZIO_PIPELINE_STOP
);
3296 * If we got an error on a leaf device, convert it to ENXIO
3297 * if the device is not accessible at all.
3299 if (zio
->io_error
&& vd
!= NULL
&& vd
->vdev_ops
->vdev_op_leaf
&&
3300 !vdev_accessible(vd
, zio
))
3301 zio
->io_error
= SET_ERROR(ENXIO
);
3304 * If we can't write to an interior vdev (mirror or RAID-Z),
3305 * set vdev_cant_write so that we stop trying to allocate from it.
3307 if (zio
->io_error
== ENXIO
&& zio
->io_type
== ZIO_TYPE_WRITE
&&
3308 vd
!= NULL
&& !vd
->vdev_ops
->vdev_op_leaf
) {
3309 vd
->vdev_cant_write
= B_TRUE
;
3313 * If a cache flush returns ENOTSUP or ENOTTY, we know that no future
3314 * attempts will ever succeed. In this case we set a persistent bit so
3315 * that we don't bother with it in the future.
3317 if ((zio
->io_error
== ENOTSUP
|| zio
->io_error
== ENOTTY
) &&
3318 zio
->io_type
== ZIO_TYPE_IOCTL
&&
3319 zio
->io_cmd
== DKIOCFLUSHWRITECACHE
&& vd
!= NULL
)
3320 vd
->vdev_nowritecache
= B_TRUE
;
3323 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
3325 if (vd
!= NULL
&& vd
->vdev_ops
->vdev_op_leaf
&&
3326 zio
->io_physdone
!= NULL
) {
3327 ASSERT(!(zio
->io_flags
& ZIO_FLAG_DELEGATED
));
3328 ASSERT(zio
->io_child_type
== ZIO_CHILD_VDEV
);
3329 zio
->io_physdone(zio
->io_logical
);
3332 return (ZIO_PIPELINE_CONTINUE
);
3336 zio_vdev_io_reissue(zio_t
*zio
)
3338 ASSERT(zio
->io_stage
== ZIO_STAGE_VDEV_IO_START
);
3339 ASSERT(zio
->io_error
== 0);
3341 zio
->io_stage
>>= 1;
3345 zio_vdev_io_redone(zio_t
*zio
)
3347 ASSERT(zio
->io_stage
== ZIO_STAGE_VDEV_IO_DONE
);
3349 zio
->io_stage
>>= 1;
3353 zio_vdev_io_bypass(zio_t
*zio
)
3355 ASSERT(zio
->io_stage
== ZIO_STAGE_VDEV_IO_START
);
3356 ASSERT(zio
->io_error
== 0);
3358 zio
->io_flags
|= ZIO_FLAG_IO_BYPASS
;
3359 zio
->io_stage
= ZIO_STAGE_VDEV_IO_ASSESS
>> 1;
3363 * ==========================================================================
3364 * Generate and verify checksums
3365 * ==========================================================================
3368 zio_checksum_generate(zio_t
*zio
)
3370 blkptr_t
*bp
= zio
->io_bp
;
3371 enum zio_checksum checksum
;
3375 * This is zio_write_phys().
3376 * We're either generating a label checksum, or none at all.
3378 checksum
= zio
->io_prop
.zp_checksum
;
3380 if (checksum
== ZIO_CHECKSUM_OFF
)
3381 return (ZIO_PIPELINE_CONTINUE
);
3383 ASSERT(checksum
== ZIO_CHECKSUM_LABEL
);
3385 if (BP_IS_GANG(bp
) && zio
->io_child_type
== ZIO_CHILD_GANG
) {
3386 ASSERT(!IO_IS_ALLOCATING(zio
));
3387 checksum
= ZIO_CHECKSUM_GANG_HEADER
;
3389 checksum
= BP_GET_CHECKSUM(bp
);
3393 zio_checksum_compute(zio
, checksum
, zio
->io_abd
, zio
->io_size
);
3395 return (ZIO_PIPELINE_CONTINUE
);
3399 zio_checksum_verify(zio_t
*zio
)
3401 zio_bad_cksum_t info
;
3402 blkptr_t
*bp
= zio
->io_bp
;
3405 ASSERT(zio
->io_vd
!= NULL
);
3409 * This is zio_read_phys().
3410 * We're either verifying a label checksum, or nothing at all.
3412 if (zio
->io_prop
.zp_checksum
== ZIO_CHECKSUM_OFF
)
3413 return (ZIO_PIPELINE_CONTINUE
);
3415 ASSERT(zio
->io_prop
.zp_checksum
== ZIO_CHECKSUM_LABEL
);
3418 if ((error
= zio_checksum_error(zio
, &info
)) != 0) {
3419 zio
->io_error
= error
;
3420 if (error
== ECKSUM
&&
3421 !(zio
->io_flags
& ZIO_FLAG_SPECULATIVE
)) {
3422 zfs_ereport_start_checksum(zio
->io_spa
,
3423 zio
->io_vd
, zio
, zio
->io_offset
,
3424 zio
->io_size
, NULL
, &info
);
3428 return (ZIO_PIPELINE_CONTINUE
);
3432 * Called by RAID-Z to ensure we don't compute the checksum twice.
3435 zio_checksum_verified(zio_t
*zio
)
3437 zio
->io_pipeline
&= ~ZIO_STAGE_CHECKSUM_VERIFY
;
3441 * ==========================================================================
3442 * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other.
3443 * An error of 0 indicates success. ENXIO indicates whole-device failure,
3444 * which may be transient (e.g. unplugged) or permament. ECKSUM and EIO
3445 * indicate errors that are specific to one I/O, and most likely permanent.
3446 * Any other error is presumed to be worse because we weren't expecting it.
3447 * ==========================================================================
3450 zio_worst_error(int e1
, int e2
)
3452 static int zio_error_rank
[] = { 0, ENXIO
, ECKSUM
, EIO
};
3455 for (r1
= 0; r1
< sizeof (zio_error_rank
) / sizeof (int); r1
++)
3456 if (e1
== zio_error_rank
[r1
])
3459 for (r2
= 0; r2
< sizeof (zio_error_rank
) / sizeof (int); r2
++)
3460 if (e2
== zio_error_rank
[r2
])
3463 return (r1
> r2
? e1
: e2
);
3467 * ==========================================================================
3469 * ==========================================================================
3472 zio_ready(zio_t
*zio
)
3474 blkptr_t
*bp
= zio
->io_bp
;
3475 zio_t
*pio
, *pio_next
;
3476 zio_link_t
*zl
= NULL
;
3478 if (zio_wait_for_children(zio
, ZIO_CHILD_GANG_BIT
| ZIO_CHILD_DDT_BIT
,
3480 return (ZIO_PIPELINE_STOP
);
3483 if (zio
->io_ready
) {
3484 ASSERT(IO_IS_ALLOCATING(zio
));
3485 ASSERT(bp
->blk_birth
== zio
->io_txg
|| BP_IS_HOLE(bp
) ||
3486 (zio
->io_flags
& ZIO_FLAG_NOPWRITE
));
3487 ASSERT(zio
->io_children
[ZIO_CHILD_GANG
][ZIO_WAIT_READY
] == 0);
3492 if (bp
!= NULL
&& bp
!= &zio
->io_bp_copy
)
3493 zio
->io_bp_copy
= *bp
;
3495 if (zio
->io_error
!= 0) {
3496 zio
->io_pipeline
= ZIO_INTERLOCK_PIPELINE
;
3498 if (zio
->io_flags
& ZIO_FLAG_IO_ALLOCATING
) {
3499 ASSERT(IO_IS_ALLOCATING(zio
));
3500 ASSERT(zio
->io_priority
== ZIO_PRIORITY_ASYNC_WRITE
);
3502 * We were unable to allocate anything, unreserve and
3503 * issue the next I/O to allocate.
3505 metaslab_class_throttle_unreserve(
3506 spa_normal_class(zio
->io_spa
),
3507 zio
->io_prop
.zp_copies
, zio
);
3508 zio_allocate_dispatch(zio
->io_spa
);
3512 mutex_enter(&zio
->io_lock
);
3513 zio
->io_state
[ZIO_WAIT_READY
] = 1;
3514 pio
= zio_walk_parents(zio
, &zl
);
3515 mutex_exit(&zio
->io_lock
);
3518 * As we notify zio's parents, new parents could be added.
3519 * New parents go to the head of zio's io_parent_list, however,
3520 * so we will (correctly) not notify them. The remainder of zio's
3521 * io_parent_list, from 'pio_next' onward, cannot change because
3522 * all parents must wait for us to be done before they can be done.
3524 for (; pio
!= NULL
; pio
= pio_next
) {
3525 pio_next
= zio_walk_parents(zio
, &zl
);
3526 zio_notify_parent(pio
, zio
, ZIO_WAIT_READY
);
3529 if (zio
->io_flags
& ZIO_FLAG_NODATA
) {
3530 if (BP_IS_GANG(bp
)) {
3531 zio
->io_flags
&= ~ZIO_FLAG_NODATA
;
3533 ASSERT((uintptr_t)zio
->io_abd
< SPA_MAXBLOCKSIZE
);
3534 zio
->io_pipeline
&= ~ZIO_VDEV_IO_STAGES
;
3538 if (zio_injection_enabled
&&
3539 zio
->io_spa
->spa_syncing_txg
== zio
->io_txg
)
3540 zio_handle_ignored_writes(zio
);
3542 return (ZIO_PIPELINE_CONTINUE
);
3546 * Update the allocation throttle accounting.
3549 zio_dva_throttle_done(zio_t
*zio
)
3551 zio_t
*lio
= zio
->io_logical
;
3552 zio_t
*pio
= zio_unique_parent(zio
);
3553 vdev_t
*vd
= zio
->io_vd
;
3554 int flags
= METASLAB_ASYNC_ALLOC
;
3556 ASSERT3P(zio
->io_bp
, !=, NULL
);
3557 ASSERT3U(zio
->io_type
, ==, ZIO_TYPE_WRITE
);
3558 ASSERT3U(zio
->io_priority
, ==, ZIO_PRIORITY_ASYNC_WRITE
);
3559 ASSERT3U(zio
->io_child_type
, ==, ZIO_CHILD_VDEV
);
3561 ASSERT3P(vd
, ==, vd
->vdev_top
);
3562 ASSERT(!(zio
->io_flags
& (ZIO_FLAG_IO_REPAIR
| ZIO_FLAG_IO_RETRY
)));
3563 ASSERT(zio
->io_flags
& ZIO_FLAG_IO_ALLOCATING
);
3564 ASSERT(!(lio
->io_flags
& ZIO_FLAG_IO_REWRITE
));
3565 ASSERT(!(lio
->io_orig_flags
& ZIO_FLAG_NODATA
));
3568 * Parents of gang children can have two flavors -- ones that
3569 * allocated the gang header (will have ZIO_FLAG_IO_REWRITE set)
3570 * and ones that allocated the constituent blocks. The allocation
3571 * throttle needs to know the allocating parent zio so we must find
3574 if (pio
->io_child_type
== ZIO_CHILD_GANG
) {
3576 * If our parent is a rewrite gang child then our grandparent
3577 * would have been the one that performed the allocation.
3579 if (pio
->io_flags
& ZIO_FLAG_IO_REWRITE
)
3580 pio
= zio_unique_parent(pio
);
3581 flags
|= METASLAB_GANG_CHILD
;
3584 ASSERT(IO_IS_ALLOCATING(pio
));
3585 ASSERT3P(zio
, !=, zio
->io_logical
);
3586 ASSERT(zio
->io_logical
!= NULL
);
3587 ASSERT(!(zio
->io_flags
& ZIO_FLAG_IO_REPAIR
));
3588 ASSERT0(zio
->io_flags
& ZIO_FLAG_NOPWRITE
);
3590 mutex_enter(&pio
->io_lock
);
3591 metaslab_group_alloc_decrement(zio
->io_spa
, vd
->vdev_id
, pio
, flags
);
3592 mutex_exit(&pio
->io_lock
);
3594 metaslab_class_throttle_unreserve(spa_normal_class(zio
->io_spa
),
3598 * Call into the pipeline to see if there is more work that
3599 * needs to be done. If there is work to be done it will be
3600 * dispatched to another taskq thread.
3602 zio_allocate_dispatch(zio
->io_spa
);
3606 zio_done(zio_t
*zio
)
3608 spa_t
*spa
= zio
->io_spa
;
3609 zio_t
*lio
= zio
->io_logical
;
3610 blkptr_t
*bp
= zio
->io_bp
;
3611 vdev_t
*vd
= zio
->io_vd
;
3612 uint64_t psize
= zio
->io_size
;
3613 zio_t
*pio
, *pio_next
;
3614 metaslab_class_t
*mc
= spa_normal_class(spa
);
3615 zio_link_t
*zl
= NULL
;
3618 * If our children haven't all completed,
3619 * wait for them and then repeat this pipeline stage.
3621 if (zio_wait_for_children(zio
, ZIO_CHILD_ALL_BITS
, ZIO_WAIT_DONE
)) {
3622 return (ZIO_PIPELINE_STOP
);
3626 * If the allocation throttle is enabled, then update the accounting.
3627 * We only track child I/Os that are part of an allocating async
3628 * write. We must do this since the allocation is performed
3629 * by the logical I/O but the actual write is done by child I/Os.
3631 if (zio
->io_flags
& ZIO_FLAG_IO_ALLOCATING
&&
3632 zio
->io_child_type
== ZIO_CHILD_VDEV
) {
3633 ASSERT(mc
->mc_alloc_throttle_enabled
);
3634 zio_dva_throttle_done(zio
);
3638 * If the allocation throttle is enabled, verify that
3639 * we have decremented the refcounts for every I/O that was throttled.
3641 if (zio
->io_flags
& ZIO_FLAG_IO_ALLOCATING
) {
3642 ASSERT(zio
->io_type
== ZIO_TYPE_WRITE
);
3643 ASSERT(zio
->io_priority
== ZIO_PRIORITY_ASYNC_WRITE
);
3645 metaslab_group_alloc_verify(spa
, zio
->io_bp
, zio
);
3646 VERIFY(refcount_not_held(&mc
->mc_alloc_slots
, zio
));
3649 for (int c
= 0; c
< ZIO_CHILD_TYPES
; c
++)
3650 for (int w
= 0; w
< ZIO_WAIT_TYPES
; w
++)
3651 ASSERT(zio
->io_children
[c
][w
] == 0);
3653 if (bp
!= NULL
&& !BP_IS_EMBEDDED(bp
)) {
3654 ASSERT(bp
->blk_pad
[0] == 0);
3655 ASSERT(bp
->blk_pad
[1] == 0);
3656 ASSERT(bcmp(bp
, &zio
->io_bp_copy
, sizeof (blkptr_t
)) == 0 ||
3657 (bp
== zio_unique_parent(zio
)->io_bp
));
3658 if (zio
->io_type
== ZIO_TYPE_WRITE
&& !BP_IS_HOLE(bp
) &&
3659 zio
->io_bp_override
== NULL
&&
3660 !(zio
->io_flags
& ZIO_FLAG_IO_REPAIR
)) {
3661 ASSERT(!BP_SHOULD_BYTESWAP(bp
));
3662 ASSERT3U(zio
->io_prop
.zp_copies
, <=, BP_GET_NDVAS(bp
));
3663 ASSERT(BP_COUNT_GANG(bp
) == 0 ||
3664 (BP_COUNT_GANG(bp
) == BP_GET_NDVAS(bp
)));
3666 if (zio
->io_flags
& ZIO_FLAG_NOPWRITE
)
3667 VERIFY(BP_EQUAL(bp
, &zio
->io_bp_orig
));
3671 * If there were child vdev/gang/ddt errors, they apply to us now.
3673 zio_inherit_child_errors(zio
, ZIO_CHILD_VDEV
);
3674 zio_inherit_child_errors(zio
, ZIO_CHILD_GANG
);
3675 zio_inherit_child_errors(zio
, ZIO_CHILD_DDT
);
3678 * If the I/O on the transformed data was successful, generate any
3679 * checksum reports now while we still have the transformed data.
3681 if (zio
->io_error
== 0) {
3682 while (zio
->io_cksum_report
!= NULL
) {
3683 zio_cksum_report_t
*zcr
= zio
->io_cksum_report
;
3684 uint64_t align
= zcr
->zcr_align
;
3685 uint64_t asize
= P2ROUNDUP(psize
, align
);
3687 abd_t
*adata
= zio
->io_abd
;
3689 if (asize
!= psize
) {
3690 adata
= abd_alloc_linear(asize
, B_TRUE
);
3691 abd_copy(adata
, zio
->io_abd
, psize
);
3692 abd_zero_off(adata
, psize
, asize
- psize
);
3696 abuf
= abd_borrow_buf_copy(adata
, asize
);
3698 zio
->io_cksum_report
= zcr
->zcr_next
;
3699 zcr
->zcr_next
= NULL
;
3700 zcr
->zcr_finish(zcr
, abuf
);
3701 zfs_ereport_free_checksum(zcr
);
3704 abd_return_buf(adata
, abuf
, asize
);
3711 zio_pop_transforms(zio
); /* note: may set zio->io_error */
3713 vdev_stat_update(zio
, psize
);
3715 if (zio
->io_error
) {
3717 * If this I/O is attached to a particular vdev,
3718 * generate an error message describing the I/O failure
3719 * at the block level. We ignore these errors if the
3720 * device is currently unavailable.
3722 if (zio
->io_error
!= ECKSUM
&& vd
!= NULL
&& !vdev_is_dead(vd
))
3723 zfs_ereport_post(FM_EREPORT_ZFS_IO
, spa
, vd
, zio
, 0, 0);
3725 if ((zio
->io_error
== EIO
|| !(zio
->io_flags
&
3726 (ZIO_FLAG_SPECULATIVE
| ZIO_FLAG_DONT_PROPAGATE
))) &&
3729 * For logical I/O requests, tell the SPA to log the
3730 * error and generate a logical data ereport.
3732 spa_log_error(spa
, zio
);
3733 zfs_ereport_post(FM_EREPORT_ZFS_DATA
, spa
, NULL
, zio
,
3738 if (zio
->io_error
&& zio
== lio
) {
3740 * Determine whether zio should be reexecuted. This will
3741 * propagate all the way to the root via zio_notify_parent().
3743 ASSERT(vd
== NULL
&& bp
!= NULL
);
3744 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
3746 if (IO_IS_ALLOCATING(zio
) &&
3747 !(zio
->io_flags
& ZIO_FLAG_CANFAIL
)) {
3748 if (zio
->io_error
!= ENOSPC
)
3749 zio
->io_reexecute
|= ZIO_REEXECUTE_NOW
;
3751 zio
->io_reexecute
|= ZIO_REEXECUTE_SUSPEND
;
3754 if ((zio
->io_type
== ZIO_TYPE_READ
||
3755 zio
->io_type
== ZIO_TYPE_FREE
) &&
3756 !(zio
->io_flags
& ZIO_FLAG_SCAN_THREAD
) &&
3757 zio
->io_error
== ENXIO
&&
3758 spa_load_state(spa
) == SPA_LOAD_NONE
&&
3759 spa_get_failmode(spa
) != ZIO_FAILURE_MODE_CONTINUE
)
3760 zio
->io_reexecute
|= ZIO_REEXECUTE_SUSPEND
;
3762 if (!(zio
->io_flags
& ZIO_FLAG_CANFAIL
) && !zio
->io_reexecute
)
3763 zio
->io_reexecute
|= ZIO_REEXECUTE_SUSPEND
;
3766 * Here is a possibly good place to attempt to do
3767 * either combinatorial reconstruction or error correction
3768 * based on checksums. It also might be a good place
3769 * to send out preliminary ereports before we suspend
3775 * If there were logical child errors, they apply to us now.
3776 * We defer this until now to avoid conflating logical child
3777 * errors with errors that happened to the zio itself when
3778 * updating vdev stats and reporting FMA events above.
3780 zio_inherit_child_errors(zio
, ZIO_CHILD_LOGICAL
);
3782 if ((zio
->io_error
|| zio
->io_reexecute
) &&
3783 IO_IS_ALLOCATING(zio
) && zio
->io_gang_leader
== zio
&&
3784 !(zio
->io_flags
& (ZIO_FLAG_IO_REWRITE
| ZIO_FLAG_NOPWRITE
)))
3785 zio_dva_unallocate(zio
, zio
->io_gang_tree
, bp
);
3787 zio_gang_tree_free(&zio
->io_gang_tree
);
3790 * Godfather I/Os should never suspend.
3792 if ((zio
->io_flags
& ZIO_FLAG_GODFATHER
) &&
3793 (zio
->io_reexecute
& ZIO_REEXECUTE_SUSPEND
))
3794 zio
->io_reexecute
= 0;
3796 if (zio
->io_reexecute
) {
3798 * This is a logical I/O that wants to reexecute.
3800 * Reexecute is top-down. When an i/o fails, if it's not
3801 * the root, it simply notifies its parent and sticks around.
3802 * The parent, seeing that it still has children in zio_done(),
3803 * does the same. This percolates all the way up to the root.
3804 * The root i/o will reexecute or suspend the entire tree.
3806 * This approach ensures that zio_reexecute() honors
3807 * all the original i/o dependency relationships, e.g.
3808 * parents not executing until children are ready.
3810 ASSERT(zio
->io_child_type
== ZIO_CHILD_LOGICAL
);
3812 zio
->io_gang_leader
= NULL
;
3814 mutex_enter(&zio
->io_lock
);
3815 zio
->io_state
[ZIO_WAIT_DONE
] = 1;
3816 mutex_exit(&zio
->io_lock
);
3819 * "The Godfather" I/O monitors its children but is
3820 * not a true parent to them. It will track them through
3821 * the pipeline but severs its ties whenever they get into
3822 * trouble (e.g. suspended). This allows "The Godfather"
3823 * I/O to return status without blocking.
3826 for (pio
= zio_walk_parents(zio
, &zl
); pio
!= NULL
;
3828 zio_link_t
*remove_zl
= zl
;
3829 pio_next
= zio_walk_parents(zio
, &zl
);
3831 if ((pio
->io_flags
& ZIO_FLAG_GODFATHER
) &&
3832 (zio
->io_reexecute
& ZIO_REEXECUTE_SUSPEND
)) {
3833 zio_remove_child(pio
, zio
, remove_zl
);
3834 zio_notify_parent(pio
, zio
, ZIO_WAIT_DONE
);
3838 if ((pio
= zio_unique_parent(zio
)) != NULL
) {
3840 * We're not a root i/o, so there's nothing to do
3841 * but notify our parent. Don't propagate errors
3842 * upward since we haven't permanently failed yet.
3844 ASSERT(!(zio
->io_flags
& ZIO_FLAG_GODFATHER
));
3845 zio
->io_flags
|= ZIO_FLAG_DONT_PROPAGATE
;
3846 zio_notify_parent(pio
, zio
, ZIO_WAIT_DONE
);
3847 } else if (zio
->io_reexecute
& ZIO_REEXECUTE_SUSPEND
) {
3849 * We'd fail again if we reexecuted now, so suspend
3850 * until conditions improve (e.g. device comes online).
3852 zio_suspend(spa
, zio
);
3855 * Reexecution is potentially a huge amount of work.
3856 * Hand it off to the otherwise-unused claim taskq.
3858 ASSERT(zio
->io_tqent
.tqent_next
== NULL
);
3859 spa_taskq_dispatch_ent(spa
, ZIO_TYPE_CLAIM
,
3860 ZIO_TASKQ_ISSUE
, (task_func_t
*)zio_reexecute
, zio
,
3863 return (ZIO_PIPELINE_STOP
);
3866 ASSERT(zio
->io_child_count
== 0);
3867 ASSERT(zio
->io_reexecute
== 0);
3868 ASSERT(zio
->io_error
== 0 || (zio
->io_flags
& ZIO_FLAG_CANFAIL
));
3871 * Report any checksum errors, since the I/O is complete.
3873 while (zio
->io_cksum_report
!= NULL
) {
3874 zio_cksum_report_t
*zcr
= zio
->io_cksum_report
;
3875 zio
->io_cksum_report
= zcr
->zcr_next
;
3876 zcr
->zcr_next
= NULL
;
3877 zcr
->zcr_finish(zcr
, NULL
);
3878 zfs_ereport_free_checksum(zcr
);
3882 * It is the responsibility of the done callback to ensure that this
3883 * particular zio is no longer discoverable for adoption, and as
3884 * such, cannot acquire any new parents.
3889 mutex_enter(&zio
->io_lock
);
3890 zio
->io_state
[ZIO_WAIT_DONE
] = 1;
3891 mutex_exit(&zio
->io_lock
);
3894 for (pio
= zio_walk_parents(zio
, &zl
); pio
!= NULL
; pio
= pio_next
) {
3895 zio_link_t
*remove_zl
= zl
;
3896 pio_next
= zio_walk_parents(zio
, &zl
);
3897 zio_remove_child(pio
, zio
, remove_zl
);
3898 zio_notify_parent(pio
, zio
, ZIO_WAIT_DONE
);
3901 if (zio
->io_waiter
!= NULL
) {
3902 mutex_enter(&zio
->io_lock
);
3903 zio
->io_executor
= NULL
;
3904 cv_broadcast(&zio
->io_cv
);
3905 mutex_exit(&zio
->io_lock
);
3910 return (ZIO_PIPELINE_STOP
);
3914 * ==========================================================================
3915 * I/O pipeline definition
3916 * ==========================================================================
3918 static zio_pipe_stage_t
*zio_pipeline
[] = {
3925 zio_checksum_generate
,
3941 zio_checksum_verify
,
3949 * Compare two zbookmark_phys_t's to see which we would reach first in a
3950 * pre-order traversal of the object tree.
3952 * This is simple in every case aside from the meta-dnode object. For all other
3953 * objects, we traverse them in order (object 1 before object 2, and so on).
3954 * However, all of these objects are traversed while traversing object 0, since
3955 * the data it points to is the list of objects. Thus, we need to convert to a
3956 * canonical representation so we can compare meta-dnode bookmarks to
3957 * non-meta-dnode bookmarks.
3959 * We do this by calculating "equivalents" for each field of the zbookmark.
3960 * zbookmarks outside of the meta-dnode use their own object and level, and
3961 * calculate the level 0 equivalent (the first L0 blkid that is contained in the
3962 * blocks this bookmark refers to) by multiplying their blkid by their span
3963 * (the number of L0 blocks contained within one block at their level).
3964 * zbookmarks inside the meta-dnode calculate their object equivalent
3965 * (which is L0equiv * dnodes per data block), use 0 for their L0equiv, and use
3966 * level + 1<<31 (any value larger than a level could ever be) for their level.
3967 * This causes them to always compare before a bookmark in their object
3968 * equivalent, compare appropriately to bookmarks in other objects, and to
3969 * compare appropriately to other bookmarks in the meta-dnode.
3972 zbookmark_compare(uint16_t dbss1
, uint8_t ibs1
, uint16_t dbss2
, uint8_t ibs2
,
3973 const zbookmark_phys_t
*zb1
, const zbookmark_phys_t
*zb2
)
3976 * These variables represent the "equivalent" values for the zbookmark,
3977 * after converting zbookmarks inside the meta dnode to their
3978 * normal-object equivalents.
3980 uint64_t zb1obj
, zb2obj
;
3981 uint64_t zb1L0
, zb2L0
;
3982 uint64_t zb1level
, zb2level
;
3984 if (zb1
->zb_object
== zb2
->zb_object
&&
3985 zb1
->zb_level
== zb2
->zb_level
&&
3986 zb1
->zb_blkid
== zb2
->zb_blkid
)
3990 * BP_SPANB calculates the span in blocks.
3992 zb1L0
= (zb1
->zb_blkid
) * BP_SPANB(ibs1
, zb1
->zb_level
);
3993 zb2L0
= (zb2
->zb_blkid
) * BP_SPANB(ibs2
, zb2
->zb_level
);
3995 if (zb1
->zb_object
== DMU_META_DNODE_OBJECT
) {
3996 zb1obj
= zb1L0
* (dbss1
<< (SPA_MINBLOCKSHIFT
- DNODE_SHIFT
));
3998 zb1level
= zb1
->zb_level
+ COMPARE_META_LEVEL
;
4000 zb1obj
= zb1
->zb_object
;
4001 zb1level
= zb1
->zb_level
;
4004 if (zb2
->zb_object
== DMU_META_DNODE_OBJECT
) {
4005 zb2obj
= zb2L0
* (dbss2
<< (SPA_MINBLOCKSHIFT
- DNODE_SHIFT
));
4007 zb2level
= zb2
->zb_level
+ COMPARE_META_LEVEL
;
4009 zb2obj
= zb2
->zb_object
;
4010 zb2level
= zb2
->zb_level
;
4013 /* Now that we have a canonical representation, do the comparison. */
4014 if (zb1obj
!= zb2obj
)
4015 return (zb1obj
< zb2obj
? -1 : 1);
4016 else if (zb1L0
!= zb2L0
)
4017 return (zb1L0
< zb2L0
? -1 : 1);
4018 else if (zb1level
!= zb2level
)
4019 return (zb1level
> zb2level
? -1 : 1);
4021 * This can (theoretically) happen if the bookmarks have the same object
4022 * and level, but different blkids, if the block sizes are not the same.
4023 * There is presently no way to change the indirect block sizes
4029 * This function checks the following: given that last_block is the place that
4030 * our traversal stopped last time, does that guarantee that we've visited
4031 * every node under subtree_root? Therefore, we can't just use the raw output
4032 * of zbookmark_compare. We have to pass in a modified version of
4033 * subtree_root; by incrementing the block id, and then checking whether
4034 * last_block is before or equal to that, we can tell whether or not having
4035 * visited last_block implies that all of subtree_root's children have been
4039 zbookmark_subtree_completed(const dnode_phys_t
*dnp
,
4040 const zbookmark_phys_t
*subtree_root
, const zbookmark_phys_t
*last_block
)
4042 zbookmark_phys_t mod_zb
= *subtree_root
;
4044 ASSERT(last_block
->zb_level
== 0);
4046 /* The objset_phys_t isn't before anything. */
4051 * We pass in 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT) for the
4052 * data block size in sectors, because that variable is only used if
4053 * the bookmark refers to a block in the meta-dnode. Since we don't
4054 * know without examining it what object it refers to, and there's no
4055 * harm in passing in this value in other cases, we always pass it in.
4057 * We pass in 0 for the indirect block size shift because zb2 must be
4058 * level 0. The indirect block size is only used to calculate the span
4059 * of the bookmark, but since the bookmark must be level 0, the span is
4060 * always 1, so the math works out.
4062 * If you make changes to how the zbookmark_compare code works, be sure
4063 * to make sure that this code still works afterwards.
4065 return (zbookmark_compare(dnp
->dn_datablkszsec
, dnp
->dn_indblkshift
,
4066 1ULL << (DNODE_BLOCK_SHIFT
- SPA_MINBLOCKSHIFT
), 0, &mod_zb
,