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.
27 #include <sys/sysmacros.h>
28 #include <sys/zfs_context.h>
29 #include <sys/fm/fs/zfs.h>
32 #include <sys/spa_impl.h>
33 #include <sys/vdev_impl.h>
34 #include <sys/zio_impl.h>
35 #include <sys/zio_compress.h>
36 #include <sys/zio_checksum.h>
37 #include <sys/dmu_objset.h>
40 #include <sys/blkptr.h>
41 #include <sys/zfeature.h>
42 #include <sys/metaslab_impl.h>
44 #include <sys/trace_zio.h>
48 * ==========================================================================
49 * I/O type descriptions
50 * ==========================================================================
52 const char *zio_type_name[ZIO_TYPES] = {
54 * Note: Linux kernel thread name length is limited
55 * so these names will differ from upstream open zfs.
57 "z_null", "z_rd", "z_wr", "z_fr", "z_cl", "z_ioctl"
60 int zio_dva_throttle_enabled = B_TRUE;
63 * ==========================================================================
65 * ==========================================================================
67 kmem_cache_t *zio_cache;
68 kmem_cache_t *zio_link_cache;
69 kmem_cache_t *zio_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
70 kmem_cache_t *zio_data_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
71 #if defined(ZFS_DEBUG) && !defined(_KERNEL)
72 uint64_t zio_buf_cache_allocs[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
73 uint64_t zio_buf_cache_frees[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
76 int zio_delay_max = ZIO_DELAY_MAX;
78 #define ZIO_PIPELINE_CONTINUE 0x100
79 #define ZIO_PIPELINE_STOP 0x101
81 #define BP_SPANB(indblkshift, level) \
82 (((uint64_t)1) << ((level) * ((indblkshift) - SPA_BLKPTRSHIFT)))
83 #define COMPARE_META_LEVEL 0x80000000ul
85 * The following actions directly effect the spa's sync-to-convergence logic.
86 * The values below define the sync pass when we start performing the action.
87 * Care should be taken when changing these values as they directly impact
88 * spa_sync() performance. Tuning these values may introduce subtle performance
89 * pathologies and should only be done in the context of performance analysis.
90 * These tunables will eventually be removed and replaced with #defines once
91 * enough analysis has been done to determine optimal values.
93 * The 'zfs_sync_pass_deferred_free' pass must be greater than 1 to ensure that
94 * regular blocks are not deferred.
96 int zfs_sync_pass_deferred_free = 2; /* defer frees starting in this pass */
97 int zfs_sync_pass_dont_compress = 5; /* don't compress starting in this pass */
98 int zfs_sync_pass_rewrite = 2; /* rewrite new bps starting in this pass */
101 * An allocating zio is one that either currently has the DVA allocate
102 * stage set or will have it later in its lifetime.
104 #define IO_IS_ALLOCATING(zio) ((zio)->io_orig_pipeline & ZIO_STAGE_DVA_ALLOCATE)
106 int zio_requeue_io_start_cut_in_line = 1;
109 int zio_buf_debug_limit = 16384;
111 int zio_buf_debug_limit = 0;
114 static inline void __zio_execute(zio_t *zio);
116 static void zio_taskq_dispatch(zio_t *, zio_taskq_type_t, boolean_t);
122 vmem_t *data_alloc_arena = NULL;
124 zio_cache = kmem_cache_create("zio_cache",
125 sizeof (zio_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
126 zio_link_cache = kmem_cache_create("zio_link_cache",
127 sizeof (zio_link_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
130 * For small buffers, we want a cache for each multiple of
131 * SPA_MINBLOCKSIZE. For larger buffers, we want a cache
132 * for each quarter-power of 2.
134 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) {
135 size_t size = (c + 1) << SPA_MINBLOCKSHIFT;
138 size_t cflags = (size > zio_buf_debug_limit) ? KMC_NODEBUG : 0;
140 #if defined(_ILP32) && defined(_KERNEL)
142 * Cache size limited to 1M on 32-bit platforms until ARC
143 * buffers no longer require virtual address space.
145 if (size > zfs_max_recordsize)
154 * If we are using watchpoints, put each buffer on its own page,
155 * to eliminate the performance overhead of trapping to the
156 * kernel when modifying a non-watched buffer that shares the
157 * page with a watched buffer.
159 if (arc_watch && !IS_P2ALIGNED(size, PAGESIZE))
162 * Here's the problem - on 4K native devices in userland on
163 * Linux using O_DIRECT, buffers must be 4K aligned or I/O
164 * will fail with EINVAL, causing zdb (and others) to coredump.
165 * Since userland probably doesn't need optimized buffer caches,
166 * we just force 4K alignment on everything.
168 align = 8 * SPA_MINBLOCKSIZE;
170 if (size <= 4 * SPA_MINBLOCKSIZE) {
171 align = SPA_MINBLOCKSIZE;
172 } else if (IS_P2ALIGNED(size, p2 >> 2)) {
173 align = MIN(p2 >> 2, PAGESIZE);
179 (void) sprintf(name, "zio_buf_%lu", (ulong_t)size);
180 zio_buf_cache[c] = kmem_cache_create(name, size,
181 align, NULL, NULL, NULL, NULL, NULL, cflags);
183 (void) sprintf(name, "zio_data_buf_%lu", (ulong_t)size);
184 zio_data_buf_cache[c] = kmem_cache_create(name, size,
185 align, NULL, NULL, NULL, NULL,
186 data_alloc_arena, cflags);
191 ASSERT(zio_buf_cache[c] != NULL);
192 if (zio_buf_cache[c - 1] == NULL)
193 zio_buf_cache[c - 1] = zio_buf_cache[c];
195 ASSERT(zio_data_buf_cache[c] != NULL);
196 if (zio_data_buf_cache[c - 1] == NULL)
197 zio_data_buf_cache[c - 1] = zio_data_buf_cache[c];
209 kmem_cache_t *last_cache = NULL;
210 kmem_cache_t *last_data_cache = NULL;
212 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) {
215 * Cache size limited to 1M on 32-bit platforms until ARC
216 * buffers no longer require virtual address space.
218 if (((c + 1) << SPA_MINBLOCKSHIFT) > zfs_max_recordsize)
221 #if defined(ZFS_DEBUG) && !defined(_KERNEL)
222 if (zio_buf_cache_allocs[c] != zio_buf_cache_frees[c])
223 (void) printf("zio_fini: [%d] %llu != %llu\n",
224 (int)((c + 1) << SPA_MINBLOCKSHIFT),
225 (long long unsigned)zio_buf_cache_allocs[c],
226 (long long unsigned)zio_buf_cache_frees[c]);
228 if (zio_buf_cache[c] != last_cache) {
229 last_cache = zio_buf_cache[c];
230 kmem_cache_destroy(zio_buf_cache[c]);
232 zio_buf_cache[c] = NULL;
234 if (zio_data_buf_cache[c] != last_data_cache) {
235 last_data_cache = zio_data_buf_cache[c];
236 kmem_cache_destroy(zio_data_buf_cache[c]);
238 zio_data_buf_cache[c] = NULL;
241 kmem_cache_destroy(zio_link_cache);
242 kmem_cache_destroy(zio_cache);
250 * ==========================================================================
251 * Allocate and free I/O buffers
252 * ==========================================================================
256 * Use zio_buf_alloc to allocate ZFS metadata. This data will appear in a
257 * crashdump if the kernel panics, so use it judiciously. Obviously, it's
258 * useful to inspect ZFS metadata, but if possible, we should avoid keeping
259 * excess / transient data in-core during a crashdump.
262 zio_buf_alloc(size_t size)
264 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
266 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
267 #if defined(ZFS_DEBUG) && !defined(_KERNEL)
268 atomic_add_64(&zio_buf_cache_allocs[c], 1);
271 return (kmem_cache_alloc(zio_buf_cache[c], KM_PUSHPAGE));
275 * Use zio_data_buf_alloc to allocate data. The data will not appear in a
276 * crashdump if the kernel panics. This exists so that we will limit the amount
277 * of ZFS data that shows up in a kernel crashdump. (Thus reducing the amount
278 * of kernel heap dumped to disk when the kernel panics)
281 zio_data_buf_alloc(size_t size)
283 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
285 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
287 return (kmem_cache_alloc(zio_data_buf_cache[c], KM_PUSHPAGE));
291 zio_buf_free(void *buf, size_t size)
293 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
295 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
296 #if defined(ZFS_DEBUG) && !defined(_KERNEL)
297 atomic_add_64(&zio_buf_cache_frees[c], 1);
300 kmem_cache_free(zio_buf_cache[c], buf);
304 zio_data_buf_free(void *buf, size_t size)
306 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
308 VERIFY3U(c, <, SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
310 kmem_cache_free(zio_data_buf_cache[c], buf);
314 zio_abd_free(void *abd, size_t size)
316 abd_free((abd_t *)abd);
320 * ==========================================================================
321 * Push and pop I/O transform buffers
322 * ==========================================================================
325 zio_push_transform(zio_t *zio, abd_t *data, uint64_t size, uint64_t bufsize,
326 zio_transform_func_t *transform)
328 zio_transform_t *zt = kmem_alloc(sizeof (zio_transform_t), KM_SLEEP);
331 * Ensure that anyone expecting this zio to contain a linear ABD isn't
332 * going to get a nasty surprise when they try to access the data.
334 IMPLY(abd_is_linear(zio->io_abd), abd_is_linear(data));
336 zt->zt_orig_abd = zio->io_abd;
337 zt->zt_orig_size = zio->io_size;
338 zt->zt_bufsize = bufsize;
339 zt->zt_transform = transform;
341 zt->zt_next = zio->io_transform_stack;
342 zio->io_transform_stack = zt;
349 zio_pop_transforms(zio_t *zio)
353 while ((zt = zio->io_transform_stack) != NULL) {
354 if (zt->zt_transform != NULL)
355 zt->zt_transform(zio,
356 zt->zt_orig_abd, zt->zt_orig_size);
358 if (zt->zt_bufsize != 0)
359 abd_free(zio->io_abd);
361 zio->io_abd = zt->zt_orig_abd;
362 zio->io_size = zt->zt_orig_size;
363 zio->io_transform_stack = zt->zt_next;
365 kmem_free(zt, sizeof (zio_transform_t));
370 * ==========================================================================
371 * I/O transform callbacks for subblocks and decompression
372 * ==========================================================================
375 zio_subblock(zio_t *zio, abd_t *data, uint64_t size)
377 ASSERT(zio->io_size > size);
379 if (zio->io_type == ZIO_TYPE_READ)
380 abd_copy(data, zio->io_abd, size);
384 zio_decompress(zio_t *zio, abd_t *data, uint64_t size)
386 if (zio->io_error == 0) {
387 void *tmp = abd_borrow_buf(data, size);
388 int ret = zio_decompress_data(BP_GET_COMPRESS(zio->io_bp),
389 zio->io_abd, tmp, zio->io_size, size);
390 abd_return_buf_copy(data, tmp, size);
393 zio->io_error = SET_ERROR(EIO);
398 * ==========================================================================
399 * I/O parent/child relationships and pipeline interlocks
400 * ==========================================================================
403 zio_walk_parents(zio_t *cio, zio_link_t **zl)
405 list_t *pl = &cio->io_parent_list;
407 *zl = (*zl == NULL) ? list_head(pl) : list_next(pl, *zl);
411 ASSERT((*zl)->zl_child == cio);
412 return ((*zl)->zl_parent);
416 zio_walk_children(zio_t *pio, zio_link_t **zl)
418 list_t *cl = &pio->io_child_list;
420 *zl = (*zl == NULL) ? list_head(cl) : list_next(cl, *zl);
424 ASSERT((*zl)->zl_parent == pio);
425 return ((*zl)->zl_child);
429 zio_unique_parent(zio_t *cio)
431 zio_link_t *zl = NULL;
432 zio_t *pio = zio_walk_parents(cio, &zl);
434 VERIFY3P(zio_walk_parents(cio, &zl), ==, NULL);
439 zio_add_child(zio_t *pio, zio_t *cio)
441 zio_link_t *zl = kmem_cache_alloc(zio_link_cache, KM_SLEEP);
445 * Logical I/Os can have logical, gang, or vdev children.
446 * Gang I/Os can have gang or vdev children.
447 * Vdev I/Os can only have vdev children.
448 * The following ASSERT captures all of these constraints.
450 ASSERT(cio->io_child_type <= pio->io_child_type);
455 mutex_enter(&cio->io_lock);
456 mutex_enter(&pio->io_lock);
458 ASSERT(pio->io_state[ZIO_WAIT_DONE] == 0);
460 for (w = 0; w < ZIO_WAIT_TYPES; w++)
461 pio->io_children[cio->io_child_type][w] += !cio->io_state[w];
463 list_insert_head(&pio->io_child_list, zl);
464 list_insert_head(&cio->io_parent_list, zl);
466 pio->io_child_count++;
467 cio->io_parent_count++;
469 mutex_exit(&pio->io_lock);
470 mutex_exit(&cio->io_lock);
474 zio_remove_child(zio_t *pio, zio_t *cio, zio_link_t *zl)
476 ASSERT(zl->zl_parent == pio);
477 ASSERT(zl->zl_child == cio);
479 mutex_enter(&cio->io_lock);
480 mutex_enter(&pio->io_lock);
482 list_remove(&pio->io_child_list, zl);
483 list_remove(&cio->io_parent_list, zl);
485 pio->io_child_count--;
486 cio->io_parent_count--;
488 mutex_exit(&pio->io_lock);
489 mutex_exit(&cio->io_lock);
490 kmem_cache_free(zio_link_cache, zl);
494 zio_wait_for_children(zio_t *zio, enum zio_child child, enum zio_wait_type wait)
496 uint64_t *countp = &zio->io_children[child][wait];
497 boolean_t waiting = B_FALSE;
499 mutex_enter(&zio->io_lock);
500 ASSERT(zio->io_stall == NULL);
503 ASSERT3U(zio->io_stage, !=, ZIO_STAGE_OPEN);
504 zio->io_stall = countp;
507 mutex_exit(&zio->io_lock);
512 __attribute__((always_inline))
514 zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait)
516 uint64_t *countp = &pio->io_children[zio->io_child_type][wait];
517 int *errorp = &pio->io_child_error[zio->io_child_type];
519 mutex_enter(&pio->io_lock);
520 if (zio->io_error && !(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE))
521 *errorp = zio_worst_error(*errorp, zio->io_error);
522 pio->io_reexecute |= zio->io_reexecute;
523 ASSERT3U(*countp, >, 0);
527 if (*countp == 0 && pio->io_stall == countp) {
528 zio_taskq_type_t type =
529 pio->io_stage < ZIO_STAGE_VDEV_IO_START ? ZIO_TASKQ_ISSUE :
531 pio->io_stall = NULL;
532 mutex_exit(&pio->io_lock);
534 * Dispatch the parent zio in its own taskq so that
535 * the child can continue to make progress. This also
536 * prevents overflowing the stack when we have deeply nested
537 * parent-child relationships.
539 zio_taskq_dispatch(pio, type, B_FALSE);
541 mutex_exit(&pio->io_lock);
546 zio_inherit_child_errors(zio_t *zio, enum zio_child c)
548 if (zio->io_child_error[c] != 0 && zio->io_error == 0)
549 zio->io_error = zio->io_child_error[c];
553 zio_bookmark_compare(const void *x1, const void *x2)
555 const zio_t *z1 = x1;
556 const zio_t *z2 = x2;
558 if (z1->io_bookmark.zb_objset < z2->io_bookmark.zb_objset)
560 if (z1->io_bookmark.zb_objset > z2->io_bookmark.zb_objset)
563 if (z1->io_bookmark.zb_object < z2->io_bookmark.zb_object)
565 if (z1->io_bookmark.zb_object > z2->io_bookmark.zb_object)
568 if (z1->io_bookmark.zb_level < z2->io_bookmark.zb_level)
570 if (z1->io_bookmark.zb_level > z2->io_bookmark.zb_level)
573 if (z1->io_bookmark.zb_blkid < z2->io_bookmark.zb_blkid)
575 if (z1->io_bookmark.zb_blkid > z2->io_bookmark.zb_blkid)
587 * ==========================================================================
588 * Create the various types of I/O (read, write, free, etc)
589 * ==========================================================================
592 zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
593 abd_t *data, uint64_t lsize, uint64_t psize, zio_done_func_t *done,
594 void *private, zio_type_t type, zio_priority_t priority,
595 enum zio_flag flags, vdev_t *vd, uint64_t offset,
596 const zbookmark_phys_t *zb, enum zio_stage stage,
597 enum zio_stage pipeline)
601 ASSERT3U(psize, <=, SPA_MAXBLOCKSIZE);
602 ASSERT(P2PHASE(psize, SPA_MINBLOCKSIZE) == 0);
603 ASSERT(P2PHASE(offset, SPA_MINBLOCKSIZE) == 0);
605 ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER));
606 ASSERT(!bp || !(flags & ZIO_FLAG_CONFIG_WRITER));
607 ASSERT(vd || stage == ZIO_STAGE_OPEN);
609 IMPLY(lsize != psize, (flags & ZIO_FLAG_RAW) != 0);
611 zio = kmem_cache_alloc(zio_cache, KM_SLEEP);
612 bzero(zio, sizeof (zio_t));
614 mutex_init(&zio->io_lock, NULL, MUTEX_NOLOCKDEP, NULL);
615 cv_init(&zio->io_cv, NULL, CV_DEFAULT, NULL);
617 list_create(&zio->io_parent_list, sizeof (zio_link_t),
618 offsetof(zio_link_t, zl_parent_node));
619 list_create(&zio->io_child_list, sizeof (zio_link_t),
620 offsetof(zio_link_t, zl_child_node));
621 metaslab_trace_init(&zio->io_alloc_list);
624 zio->io_child_type = ZIO_CHILD_VDEV;
625 else if (flags & ZIO_FLAG_GANG_CHILD)
626 zio->io_child_type = ZIO_CHILD_GANG;
627 else if (flags & ZIO_FLAG_DDT_CHILD)
628 zio->io_child_type = ZIO_CHILD_DDT;
630 zio->io_child_type = ZIO_CHILD_LOGICAL;
633 zio->io_bp = (blkptr_t *)bp;
634 zio->io_bp_copy = *bp;
635 zio->io_bp_orig = *bp;
636 if (type != ZIO_TYPE_WRITE ||
637 zio->io_child_type == ZIO_CHILD_DDT)
638 zio->io_bp = &zio->io_bp_copy; /* so caller can free */
639 if (zio->io_child_type == ZIO_CHILD_LOGICAL)
640 zio->io_logical = zio;
641 if (zio->io_child_type > ZIO_CHILD_GANG && BP_IS_GANG(bp))
642 pipeline |= ZIO_GANG_STAGES;
648 zio->io_private = private;
650 zio->io_priority = priority;
652 zio->io_offset = offset;
653 zio->io_orig_abd = zio->io_abd = data;
654 zio->io_orig_size = zio->io_size = psize;
655 zio->io_lsize = lsize;
656 zio->io_orig_flags = zio->io_flags = flags;
657 zio->io_orig_stage = zio->io_stage = stage;
658 zio->io_orig_pipeline = zio->io_pipeline = pipeline;
659 zio->io_pipeline_trace = ZIO_STAGE_OPEN;
661 zio->io_state[ZIO_WAIT_READY] = (stage >= ZIO_STAGE_READY);
662 zio->io_state[ZIO_WAIT_DONE] = (stage >= ZIO_STAGE_DONE);
665 zio->io_bookmark = *zb;
668 if (zio->io_logical == NULL)
669 zio->io_logical = pio->io_logical;
670 if (zio->io_child_type == ZIO_CHILD_GANG)
671 zio->io_gang_leader = pio->io_gang_leader;
672 zio_add_child(pio, zio);
675 taskq_init_ent(&zio->io_tqent);
681 zio_destroy(zio_t *zio)
683 metaslab_trace_fini(&zio->io_alloc_list);
684 list_destroy(&zio->io_parent_list);
685 list_destroy(&zio->io_child_list);
686 mutex_destroy(&zio->io_lock);
687 cv_destroy(&zio->io_cv);
688 kmem_cache_free(zio_cache, zio);
692 zio_null(zio_t *pio, spa_t *spa, vdev_t *vd, zio_done_func_t *done,
693 void *private, enum zio_flag flags)
697 zio = zio_create(pio, spa, 0, NULL, NULL, 0, 0, done, private,
698 ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL,
699 ZIO_STAGE_OPEN, ZIO_INTERLOCK_PIPELINE);
705 zio_root(spa_t *spa, zio_done_func_t *done, void *private, enum zio_flag flags)
707 return (zio_null(NULL, spa, NULL, done, private, flags));
711 zfs_blkptr_verify(spa_t *spa, const blkptr_t *bp)
715 if (!DMU_OT_IS_VALID(BP_GET_TYPE(bp))) {
716 zfs_panic_recover("blkptr at %p has invalid TYPE %llu",
717 bp, (longlong_t)BP_GET_TYPE(bp));
719 if (BP_GET_CHECKSUM(bp) >= ZIO_CHECKSUM_FUNCTIONS ||
720 BP_GET_CHECKSUM(bp) <= ZIO_CHECKSUM_ON) {
721 zfs_panic_recover("blkptr at %p has invalid CHECKSUM %llu",
722 bp, (longlong_t)BP_GET_CHECKSUM(bp));
724 if (BP_GET_COMPRESS(bp) >= ZIO_COMPRESS_FUNCTIONS ||
725 BP_GET_COMPRESS(bp) <= ZIO_COMPRESS_ON) {
726 zfs_panic_recover("blkptr at %p has invalid COMPRESS %llu",
727 bp, (longlong_t)BP_GET_COMPRESS(bp));
729 if (BP_GET_LSIZE(bp) > SPA_MAXBLOCKSIZE) {
730 zfs_panic_recover("blkptr at %p has invalid LSIZE %llu",
731 bp, (longlong_t)BP_GET_LSIZE(bp));
733 if (BP_GET_PSIZE(bp) > SPA_MAXBLOCKSIZE) {
734 zfs_panic_recover("blkptr at %p has invalid PSIZE %llu",
735 bp, (longlong_t)BP_GET_PSIZE(bp));
738 if (BP_IS_EMBEDDED(bp)) {
739 if (BPE_GET_ETYPE(bp) > NUM_BP_EMBEDDED_TYPES) {
740 zfs_panic_recover("blkptr at %p has invalid ETYPE %llu",
741 bp, (longlong_t)BPE_GET_ETYPE(bp));
746 * Pool-specific checks.
748 * Note: it would be nice to verify that the blk_birth and
749 * BP_PHYSICAL_BIRTH() are not too large. However, spa_freeze()
750 * allows the birth time of log blocks (and dmu_sync()-ed blocks
751 * that are in the log) to be arbitrarily large.
753 for (i = 0; i < BP_GET_NDVAS(bp); i++) {
754 uint64_t vdevid = DVA_GET_VDEV(&bp->blk_dva[i]);
756 uint64_t offset, asize;
757 if (vdevid >= spa->spa_root_vdev->vdev_children) {
758 zfs_panic_recover("blkptr at %p DVA %u has invalid "
760 bp, i, (longlong_t)vdevid);
763 vd = spa->spa_root_vdev->vdev_child[vdevid];
765 zfs_panic_recover("blkptr at %p DVA %u has invalid "
767 bp, i, (longlong_t)vdevid);
770 if (vd->vdev_ops == &vdev_hole_ops) {
771 zfs_panic_recover("blkptr at %p DVA %u has hole "
773 bp, i, (longlong_t)vdevid);
776 if (vd->vdev_ops == &vdev_missing_ops) {
778 * "missing" vdevs are valid during import, but we
779 * don't have their detailed info (e.g. asize), so
780 * we can't perform any more checks on them.
784 offset = DVA_GET_OFFSET(&bp->blk_dva[i]);
785 asize = DVA_GET_ASIZE(&bp->blk_dva[i]);
787 asize = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE);
788 if (offset + asize > vd->vdev_asize) {
789 zfs_panic_recover("blkptr at %p DVA %u has invalid "
791 bp, i, (longlong_t)offset);
797 zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
798 abd_t *data, uint64_t size, zio_done_func_t *done, void *private,
799 zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb)
803 zfs_blkptr_verify(spa, bp);
805 zio = zio_create(pio, spa, BP_PHYSICAL_BIRTH(bp), bp,
806 data, size, size, done, private,
807 ZIO_TYPE_READ, priority, flags, NULL, 0, zb,
808 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ?
809 ZIO_DDT_CHILD_READ_PIPELINE : ZIO_READ_PIPELINE);
815 zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
816 abd_t *data, uint64_t lsize, uint64_t psize, const zio_prop_t *zp,
817 zio_done_func_t *ready, zio_done_func_t *children_ready,
818 zio_done_func_t *physdone, zio_done_func_t *done,
819 void *private, zio_priority_t priority, enum zio_flag flags,
820 const zbookmark_phys_t *zb)
824 ASSERT(zp->zp_checksum >= ZIO_CHECKSUM_OFF &&
825 zp->zp_checksum < ZIO_CHECKSUM_FUNCTIONS &&
826 zp->zp_compress >= ZIO_COMPRESS_OFF &&
827 zp->zp_compress < ZIO_COMPRESS_FUNCTIONS &&
828 DMU_OT_IS_VALID(zp->zp_type) &&
831 zp->zp_copies <= spa_max_replication(spa));
833 zio = zio_create(pio, spa, txg, bp, data, lsize, psize, done, private,
834 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb,
835 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ?
836 ZIO_DDT_CHILD_WRITE_PIPELINE : ZIO_WRITE_PIPELINE);
838 zio->io_ready = ready;
839 zio->io_children_ready = children_ready;
840 zio->io_physdone = physdone;
844 * Data can be NULL if we are going to call zio_write_override() to
845 * provide the already-allocated BP. But we may need the data to
846 * verify a dedup hit (if requested). In this case, don't try to
847 * dedup (just take the already-allocated BP verbatim).
849 if (data == NULL && zio->io_prop.zp_dedup_verify) {
850 zio->io_prop.zp_dedup = zio->io_prop.zp_dedup_verify = B_FALSE;
857 zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, abd_t *data,
858 uint64_t size, zio_done_func_t *done, void *private,
859 zio_priority_t priority, enum zio_flag flags, zbookmark_phys_t *zb)
863 zio = zio_create(pio, spa, txg, bp, data, size, size, done, private,
864 ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_IO_REWRITE, NULL, 0, zb,
865 ZIO_STAGE_OPEN, ZIO_REWRITE_PIPELINE);
871 zio_write_override(zio_t *zio, blkptr_t *bp, int copies, boolean_t nopwrite)
873 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
874 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
875 ASSERT(zio->io_stage == ZIO_STAGE_OPEN);
876 ASSERT(zio->io_txg == spa_syncing_txg(zio->io_spa));
879 * We must reset the io_prop to match the values that existed
880 * when the bp was first written by dmu_sync() keeping in mind
881 * that nopwrite and dedup are mutually exclusive.
883 zio->io_prop.zp_dedup = nopwrite ? B_FALSE : zio->io_prop.zp_dedup;
884 zio->io_prop.zp_nopwrite = nopwrite;
885 zio->io_prop.zp_copies = copies;
886 zio->io_bp_override = bp;
890 zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp)
894 * The check for EMBEDDED is a performance optimization. We
895 * process the free here (by ignoring it) rather than
896 * putting it on the list and then processing it in zio_free_sync().
898 if (BP_IS_EMBEDDED(bp))
900 metaslab_check_free(spa, bp);
903 * Frees that are for the currently-syncing txg, are not going to be
904 * deferred, and which will not need to do a read (i.e. not GANG or
905 * DEDUP), can be processed immediately. Otherwise, put them on the
906 * in-memory list for later processing.
908 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp) ||
909 txg != spa->spa_syncing_txg ||
910 spa_sync_pass(spa) >= zfs_sync_pass_deferred_free) {
911 bplist_append(&spa->spa_free_bplist[txg & TXG_MASK], bp);
913 VERIFY0(zio_wait(zio_free_sync(NULL, spa, txg, bp, 0)));
918 zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
922 enum zio_stage stage = ZIO_FREE_PIPELINE;
924 ASSERT(!BP_IS_HOLE(bp));
925 ASSERT(spa_syncing_txg(spa) == txg);
926 ASSERT(spa_sync_pass(spa) < zfs_sync_pass_deferred_free);
928 if (BP_IS_EMBEDDED(bp))
929 return (zio_null(pio, spa, NULL, NULL, NULL, 0));
931 metaslab_check_free(spa, bp);
935 * GANG and DEDUP blocks can induce a read (for the gang block header,
936 * or the DDT), so issue them asynchronously so that this thread is
939 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp))
940 stage |= ZIO_STAGE_ISSUE_ASYNC;
942 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
943 BP_GET_PSIZE(bp), NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_NOW,
944 flags, NULL, 0, NULL, ZIO_STAGE_OPEN, stage);
950 zio_claim(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
951 zio_done_func_t *done, void *private, enum zio_flag flags)
955 dprintf_bp(bp, "claiming in txg %llu", txg);
957 if (BP_IS_EMBEDDED(bp))
958 return (zio_null(pio, spa, NULL, NULL, NULL, 0));
961 * A claim is an allocation of a specific block. Claims are needed
962 * to support immediate writes in the intent log. The issue is that
963 * immediate writes contain committed data, but in a txg that was
964 * *not* committed. Upon opening the pool after an unclean shutdown,
965 * the intent log claims all blocks that contain immediate write data
966 * so that the SPA knows they're in use.
968 * All claims *must* be resolved in the first txg -- before the SPA
969 * starts allocating blocks -- so that nothing is allocated twice.
970 * If txg == 0 we just verify that the block is claimable.
972 ASSERT3U(spa->spa_uberblock.ub_rootbp.blk_birth, <, spa_first_txg(spa));
973 ASSERT(txg == spa_first_txg(spa) || txg == 0);
974 ASSERT(!BP_GET_DEDUP(bp) || !spa_writeable(spa)); /* zdb(1M) */
976 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
977 BP_GET_PSIZE(bp), done, private, ZIO_TYPE_CLAIM, ZIO_PRIORITY_NOW,
978 flags, NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_CLAIM_PIPELINE);
979 ASSERT0(zio->io_queued_timestamp);
985 zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
986 zio_done_func_t *done, void *private, enum zio_flag flags)
991 if (vd->vdev_children == 0) {
992 zio = zio_create(pio, spa, 0, NULL, NULL, 0, 0, done, private,
993 ZIO_TYPE_IOCTL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL,
994 ZIO_STAGE_OPEN, ZIO_IOCTL_PIPELINE);
998 zio = zio_null(pio, spa, NULL, NULL, NULL, flags);
1000 for (c = 0; c < vd->vdev_children; c++)
1001 zio_nowait(zio_ioctl(zio, spa, vd->vdev_child[c], cmd,
1002 done, private, flags));
1009 zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
1010 abd_t *data, int checksum, zio_done_func_t *done, void *private,
1011 zio_priority_t priority, enum zio_flag flags, boolean_t labels)
1015 ASSERT(vd->vdev_children == 0);
1016 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
1017 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
1018 ASSERT3U(offset + size, <=, vd->vdev_psize);
1020 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, size, done,
1021 private, ZIO_TYPE_READ, priority, flags | ZIO_FLAG_PHYSICAL, vd,
1022 offset, NULL, ZIO_STAGE_OPEN, ZIO_READ_PHYS_PIPELINE);
1024 zio->io_prop.zp_checksum = checksum;
1030 zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
1031 abd_t *data, int checksum, zio_done_func_t *done, void *private,
1032 zio_priority_t priority, enum zio_flag flags, boolean_t labels)
1036 ASSERT(vd->vdev_children == 0);
1037 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
1038 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
1039 ASSERT3U(offset + size, <=, vd->vdev_psize);
1041 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, size, done,
1042 private, ZIO_TYPE_WRITE, priority, flags | ZIO_FLAG_PHYSICAL, vd,
1043 offset, NULL, ZIO_STAGE_OPEN, ZIO_WRITE_PHYS_PIPELINE);
1045 zio->io_prop.zp_checksum = checksum;
1047 if (zio_checksum_table[checksum].ci_flags & ZCHECKSUM_FLAG_EMBEDDED) {
1049 * zec checksums are necessarily destructive -- they modify
1050 * the end of the write buffer to hold the verifier/checksum.
1051 * Therefore, we must make a local copy in case the data is
1052 * being written to multiple places in parallel.
1054 abd_t *wbuf = abd_alloc_sametype(data, size);
1055 abd_copy(wbuf, data, size);
1057 zio_push_transform(zio, wbuf, size, size, NULL);
1064 * Create a child I/O to do some work for us.
1067 zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset,
1068 abd_t *data, uint64_t size, int type, zio_priority_t priority,
1069 enum zio_flag flags, zio_done_func_t *done, void *private)
1071 enum zio_stage pipeline = ZIO_VDEV_CHILD_PIPELINE;
1074 ASSERT(vd->vdev_parent ==
1075 (pio->io_vd ? pio->io_vd : pio->io_spa->spa_root_vdev));
1077 if (type == ZIO_TYPE_READ && bp != NULL) {
1079 * If we have the bp, then the child should perform the
1080 * checksum and the parent need not. This pushes error
1081 * detection as close to the leaves as possible and
1082 * eliminates redundant checksums in the interior nodes.
1084 pipeline |= ZIO_STAGE_CHECKSUM_VERIFY;
1085 pio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY;
1088 if (vd->vdev_children == 0)
1089 offset += VDEV_LABEL_START_SIZE;
1091 flags |= ZIO_VDEV_CHILD_FLAGS(pio) | ZIO_FLAG_DONT_PROPAGATE;
1094 * If we've decided to do a repair, the write is not speculative --
1095 * even if the original read was.
1097 if (flags & ZIO_FLAG_IO_REPAIR)
1098 flags &= ~ZIO_FLAG_SPECULATIVE;
1101 * If we're creating a child I/O that is not associated with a
1102 * top-level vdev, then the child zio is not an allocating I/O.
1103 * If this is a retried I/O then we ignore it since we will
1104 * have already processed the original allocating I/O.
1106 if (flags & ZIO_FLAG_IO_ALLOCATING &&
1107 (vd != vd->vdev_top || (flags & ZIO_FLAG_IO_RETRY))) {
1108 ASSERTV(metaslab_class_t *mc = spa_normal_class(pio->io_spa));
1110 ASSERT(mc->mc_alloc_throttle_enabled);
1111 ASSERT(type == ZIO_TYPE_WRITE);
1112 ASSERT(priority == ZIO_PRIORITY_ASYNC_WRITE);
1113 ASSERT(!(flags & ZIO_FLAG_IO_REPAIR));
1114 ASSERT(!(pio->io_flags & ZIO_FLAG_IO_REWRITE) ||
1115 pio->io_child_type == ZIO_CHILD_GANG);
1117 flags &= ~ZIO_FLAG_IO_ALLOCATING;
1121 zio = zio_create(pio, pio->io_spa, pio->io_txg, bp, data, size, size,
1122 done, private, type, priority, flags, vd, offset, &pio->io_bookmark,
1123 ZIO_STAGE_VDEV_IO_START >> 1, pipeline);
1124 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV);
1126 zio->io_physdone = pio->io_physdone;
1127 if (vd->vdev_ops->vdev_op_leaf && zio->io_logical != NULL)
1128 zio->io_logical->io_phys_children++;
1134 zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, abd_t *data, uint64_t size,
1135 int type, zio_priority_t priority, enum zio_flag flags,
1136 zio_done_func_t *done, void *private)
1140 ASSERT(vd->vdev_ops->vdev_op_leaf);
1142 zio = zio_create(NULL, vd->vdev_spa, 0, NULL,
1143 data, size, size, done, private, type, priority,
1144 flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY | ZIO_FLAG_DELEGATED,
1146 ZIO_STAGE_VDEV_IO_START >> 1, ZIO_VDEV_CHILD_PIPELINE);
1152 zio_flush(zio_t *zio, vdev_t *vd)
1154 zio_nowait(zio_ioctl(zio, zio->io_spa, vd, DKIOCFLUSHWRITECACHE,
1156 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_DONT_RETRY));
1160 zio_shrink(zio_t *zio, uint64_t size)
1162 ASSERT(zio->io_executor == NULL);
1163 ASSERT(zio->io_orig_size == zio->io_size);
1164 ASSERT(size <= zio->io_size);
1167 * We don't shrink for raidz because of problems with the
1168 * reconstruction when reading back less than the block size.
1169 * Note, BP_IS_RAIDZ() assumes no compression.
1171 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF);
1172 if (!BP_IS_RAIDZ(zio->io_bp)) {
1173 /* we are not doing a raw write */
1174 ASSERT3U(zio->io_size, ==, zio->io_lsize);
1175 zio->io_orig_size = zio->io_size = zio->io_lsize = size;
1180 * ==========================================================================
1181 * Prepare to read and write logical blocks
1182 * ==========================================================================
1186 zio_read_bp_init(zio_t *zio)
1188 blkptr_t *bp = zio->io_bp;
1190 if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF &&
1191 zio->io_child_type == ZIO_CHILD_LOGICAL &&
1192 !(zio->io_flags & ZIO_FLAG_RAW)) {
1194 BP_IS_EMBEDDED(bp) ? BPE_GET_PSIZE(bp) : BP_GET_PSIZE(bp);
1195 zio_push_transform(zio, abd_alloc_sametype(zio->io_abd, psize),
1196 psize, psize, zio_decompress);
1199 if (BP_IS_EMBEDDED(bp) && BPE_GET_ETYPE(bp) == BP_EMBEDDED_TYPE_DATA) {
1200 int psize = BPE_GET_PSIZE(bp);
1201 void *data = abd_borrow_buf(zio->io_abd, psize);
1203 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1204 decode_embedded_bp_compressed(bp, data);
1205 abd_return_buf_copy(zio->io_abd, data, psize);
1207 ASSERT(!BP_IS_EMBEDDED(bp));
1210 if (!DMU_OT_IS_METADATA(BP_GET_TYPE(bp)) && BP_GET_LEVEL(bp) == 0)
1211 zio->io_flags |= ZIO_FLAG_DONT_CACHE;
1213 if (BP_GET_TYPE(bp) == DMU_OT_DDT_ZAP)
1214 zio->io_flags |= ZIO_FLAG_DONT_CACHE;
1216 if (BP_GET_DEDUP(bp) && zio->io_child_type == ZIO_CHILD_LOGICAL)
1217 zio->io_pipeline = ZIO_DDT_READ_PIPELINE;
1219 return (ZIO_PIPELINE_CONTINUE);
1223 zio_write_bp_init(zio_t *zio)
1226 if (!IO_IS_ALLOCATING(zio))
1227 return (ZIO_PIPELINE_CONTINUE);
1229 ASSERT(zio->io_child_type != ZIO_CHILD_DDT);
1231 if (zio->io_bp_override) {
1232 blkptr_t *bp = zio->io_bp;
1233 zio_prop_t *zp = &zio->io_prop;
1235 ASSERT(bp->blk_birth != zio->io_txg);
1236 ASSERT(BP_GET_DEDUP(zio->io_bp_override) == 0);
1238 *bp = *zio->io_bp_override;
1239 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1241 if (BP_IS_EMBEDDED(bp))
1242 return (ZIO_PIPELINE_CONTINUE);
1245 * If we've been overridden and nopwrite is set then
1246 * set the flag accordingly to indicate that a nopwrite
1247 * has already occurred.
1249 if (!BP_IS_HOLE(bp) && zp->zp_nopwrite) {
1250 ASSERT(!zp->zp_dedup);
1251 ASSERT3U(BP_GET_CHECKSUM(bp), ==, zp->zp_checksum);
1252 zio->io_flags |= ZIO_FLAG_NOPWRITE;
1253 return (ZIO_PIPELINE_CONTINUE);
1256 ASSERT(!zp->zp_nopwrite);
1258 if (BP_IS_HOLE(bp) || !zp->zp_dedup)
1259 return (ZIO_PIPELINE_CONTINUE);
1261 ASSERT((zio_checksum_table[zp->zp_checksum].ci_flags &
1262 ZCHECKSUM_FLAG_DEDUP) || zp->zp_dedup_verify);
1264 if (BP_GET_CHECKSUM(bp) == zp->zp_checksum) {
1265 BP_SET_DEDUP(bp, 1);
1266 zio->io_pipeline |= ZIO_STAGE_DDT_WRITE;
1267 return (ZIO_PIPELINE_CONTINUE);
1271 * We were unable to handle this as an override bp, treat
1272 * it as a regular write I/O.
1274 zio->io_bp_override = NULL;
1275 *bp = zio->io_bp_orig;
1276 zio->io_pipeline = zio->io_orig_pipeline;
1279 return (ZIO_PIPELINE_CONTINUE);
1283 zio_write_compress(zio_t *zio)
1285 spa_t *spa = zio->io_spa;
1286 zio_prop_t *zp = &zio->io_prop;
1287 enum zio_compress compress = zp->zp_compress;
1288 blkptr_t *bp = zio->io_bp;
1289 uint64_t lsize = zio->io_lsize;
1290 uint64_t psize = zio->io_size;
1293 EQUIV(lsize != psize, (zio->io_flags & ZIO_FLAG_RAW) != 0);
1296 * If our children haven't all reached the ready stage,
1297 * wait for them and then repeat this pipeline stage.
1299 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) ||
1300 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_READY))
1301 return (ZIO_PIPELINE_STOP);
1303 if (!IO_IS_ALLOCATING(zio))
1304 return (ZIO_PIPELINE_CONTINUE);
1306 if (zio->io_children_ready != NULL) {
1308 * Now that all our children are ready, run the callback
1309 * associated with this zio in case it wants to modify the
1310 * data to be written.
1312 ASSERT3U(zp->zp_level, >, 0);
1313 zio->io_children_ready(zio);
1316 ASSERT(zio->io_child_type != ZIO_CHILD_DDT);
1317 ASSERT(zio->io_bp_override == NULL);
1319 if (!BP_IS_HOLE(bp) && bp->blk_birth == zio->io_txg) {
1321 * We're rewriting an existing block, which means we're
1322 * working on behalf of spa_sync(). For spa_sync() to
1323 * converge, it must eventually be the case that we don't
1324 * have to allocate new blocks. But compression changes
1325 * the blocksize, which forces a reallocate, and makes
1326 * convergence take longer. Therefore, after the first
1327 * few passes, stop compressing to ensure convergence.
1329 pass = spa_sync_pass(spa);
1331 ASSERT(zio->io_txg == spa_syncing_txg(spa));
1332 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1333 ASSERT(!BP_GET_DEDUP(bp));
1335 if (pass >= zfs_sync_pass_dont_compress)
1336 compress = ZIO_COMPRESS_OFF;
1338 /* Make sure someone doesn't change their mind on overwrites */
1339 ASSERT(BP_IS_EMBEDDED(bp) || MIN(zp->zp_copies + BP_IS_GANG(bp),
1340 spa_max_replication(spa)) == BP_GET_NDVAS(bp));
1343 /* If it's a compressed write that is not raw, compress the buffer. */
1344 if (compress != ZIO_COMPRESS_OFF && psize == lsize) {
1345 void *cbuf = zio_buf_alloc(lsize);
1346 psize = zio_compress_data(compress, zio->io_abd, cbuf, lsize);
1347 if (psize == 0 || psize == lsize) {
1348 compress = ZIO_COMPRESS_OFF;
1349 zio_buf_free(cbuf, lsize);
1350 } else if (!zp->zp_dedup && psize <= BPE_PAYLOAD_SIZE &&
1351 zp->zp_level == 0 && !DMU_OT_HAS_FILL(zp->zp_type) &&
1352 spa_feature_is_enabled(spa, SPA_FEATURE_EMBEDDED_DATA)) {
1353 encode_embedded_bp_compressed(bp,
1354 cbuf, compress, lsize, psize);
1355 BPE_SET_ETYPE(bp, BP_EMBEDDED_TYPE_DATA);
1356 BP_SET_TYPE(bp, zio->io_prop.zp_type);
1357 BP_SET_LEVEL(bp, zio->io_prop.zp_level);
1358 zio_buf_free(cbuf, lsize);
1359 bp->blk_birth = zio->io_txg;
1360 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1361 ASSERT(spa_feature_is_active(spa,
1362 SPA_FEATURE_EMBEDDED_DATA));
1363 return (ZIO_PIPELINE_CONTINUE);
1366 * Round up compressed size up to the ashift
1367 * of the smallest-ashift device, and zero the tail.
1368 * This ensures that the compressed size of the BP
1369 * (and thus compressratio property) are correct,
1370 * in that we charge for the padding used to fill out
1375 ASSERT3U(spa->spa_min_ashift, >=, SPA_MINBLOCKSHIFT);
1377 rounded = (size_t)P2ROUNDUP(psize,
1378 1ULL << spa->spa_min_ashift);
1379 if (rounded >= lsize) {
1380 compress = ZIO_COMPRESS_OFF;
1381 zio_buf_free(cbuf, lsize);
1384 abd_t *cdata = abd_get_from_buf(cbuf, lsize);
1385 abd_take_ownership_of_buf(cdata, B_TRUE);
1386 abd_zero_off(cdata, psize, rounded - psize);
1388 zio_push_transform(zio, cdata,
1389 psize, lsize, NULL);
1394 * We were unable to handle this as an override bp, treat
1395 * it as a regular write I/O.
1397 zio->io_bp_override = NULL;
1398 *bp = zio->io_bp_orig;
1399 zio->io_pipeline = zio->io_orig_pipeline;
1402 ASSERT3U(psize, !=, 0);
1407 * The final pass of spa_sync() must be all rewrites, but the first
1408 * few passes offer a trade-off: allocating blocks defers convergence,
1409 * but newly allocated blocks are sequential, so they can be written
1410 * to disk faster. Therefore, we allow the first few passes of
1411 * spa_sync() to allocate new blocks, but force rewrites after that.
1412 * There should only be a handful of blocks after pass 1 in any case.
1414 if (!BP_IS_HOLE(bp) && bp->blk_birth == zio->io_txg &&
1415 BP_GET_PSIZE(bp) == psize &&
1416 pass >= zfs_sync_pass_rewrite) {
1417 enum zio_stage gang_stages = zio->io_pipeline & ZIO_GANG_STAGES;
1419 zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages;
1420 zio->io_flags |= ZIO_FLAG_IO_REWRITE;
1423 zio->io_pipeline = ZIO_WRITE_PIPELINE;
1427 if (zio->io_bp_orig.blk_birth != 0 &&
1428 spa_feature_is_active(spa, SPA_FEATURE_HOLE_BIRTH)) {
1429 BP_SET_LSIZE(bp, lsize);
1430 BP_SET_TYPE(bp, zp->zp_type);
1431 BP_SET_LEVEL(bp, zp->zp_level);
1432 BP_SET_BIRTH(bp, zio->io_txg, 0);
1434 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1436 ASSERT(zp->zp_checksum != ZIO_CHECKSUM_GANG_HEADER);
1437 BP_SET_LSIZE(bp, lsize);
1438 BP_SET_TYPE(bp, zp->zp_type);
1439 BP_SET_LEVEL(bp, zp->zp_level);
1440 BP_SET_PSIZE(bp, psize);
1441 BP_SET_COMPRESS(bp, compress);
1442 BP_SET_CHECKSUM(bp, zp->zp_checksum);
1443 BP_SET_DEDUP(bp, zp->zp_dedup);
1444 BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
1446 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1447 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1448 zio->io_pipeline = ZIO_DDT_WRITE_PIPELINE;
1450 if (zp->zp_nopwrite) {
1451 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1452 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1453 zio->io_pipeline |= ZIO_STAGE_NOP_WRITE;
1456 return (ZIO_PIPELINE_CONTINUE);
1460 zio_free_bp_init(zio_t *zio)
1462 blkptr_t *bp = zio->io_bp;
1464 if (zio->io_child_type == ZIO_CHILD_LOGICAL) {
1465 if (BP_GET_DEDUP(bp))
1466 zio->io_pipeline = ZIO_DDT_FREE_PIPELINE;
1469 return (ZIO_PIPELINE_CONTINUE);
1473 * ==========================================================================
1474 * Execute the I/O pipeline
1475 * ==========================================================================
1479 zio_taskq_dispatch(zio_t *zio, zio_taskq_type_t q, boolean_t cutinline)
1481 spa_t *spa = zio->io_spa;
1482 zio_type_t t = zio->io_type;
1483 int flags = (cutinline ? TQ_FRONT : 0);
1486 * If we're a config writer or a probe, the normal issue and
1487 * interrupt threads may all be blocked waiting for the config lock.
1488 * In this case, select the otherwise-unused taskq for ZIO_TYPE_NULL.
1490 if (zio->io_flags & (ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_PROBE))
1494 * A similar issue exists for the L2ARC write thread until L2ARC 2.0.
1496 if (t == ZIO_TYPE_WRITE && zio->io_vd && zio->io_vd->vdev_aux)
1500 * If this is a high priority I/O, then use the high priority taskq if
1503 if (zio->io_priority == ZIO_PRIORITY_NOW &&
1504 spa->spa_zio_taskq[t][q + 1].stqs_count != 0)
1507 ASSERT3U(q, <, ZIO_TASKQ_TYPES);
1510 * NB: We are assuming that the zio can only be dispatched
1511 * to a single taskq at a time. It would be a grievous error
1512 * to dispatch the zio to another taskq at the same time.
1514 ASSERT(taskq_empty_ent(&zio->io_tqent));
1515 spa_taskq_dispatch_ent(spa, t, q, (task_func_t *)zio_execute, zio,
1516 flags, &zio->io_tqent);
1520 zio_taskq_member(zio_t *zio, zio_taskq_type_t q)
1522 kthread_t *executor = zio->io_executor;
1523 spa_t *spa = zio->io_spa;
1526 for (t = 0; t < ZIO_TYPES; t++) {
1527 spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q];
1529 for (i = 0; i < tqs->stqs_count; i++) {
1530 if (taskq_member(tqs->stqs_taskq[i], executor))
1539 zio_issue_async(zio_t *zio)
1541 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE);
1543 return (ZIO_PIPELINE_STOP);
1547 zio_interrupt(zio_t *zio)
1549 zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT, B_FALSE);
1553 zio_delay_interrupt(zio_t *zio)
1556 * The timeout_generic() function isn't defined in userspace, so
1557 * rather than trying to implement the function, the zio delay
1558 * functionality has been disabled for userspace builds.
1563 * If io_target_timestamp is zero, then no delay has been registered
1564 * for this IO, thus jump to the end of this function and "skip" the
1565 * delay; issuing it directly to the zio layer.
1567 if (zio->io_target_timestamp != 0) {
1568 hrtime_t now = gethrtime();
1570 if (now >= zio->io_target_timestamp) {
1572 * This IO has already taken longer than the target
1573 * delay to complete, so we don't want to delay it
1574 * any longer; we "miss" the delay and issue it
1575 * directly to the zio layer. This is likely due to
1576 * the target latency being set to a value less than
1577 * the underlying hardware can satisfy (e.g. delay
1578 * set to 1ms, but the disks take 10ms to complete an
1582 DTRACE_PROBE2(zio__delay__miss, zio_t *, zio,
1588 hrtime_t diff = zio->io_target_timestamp - now;
1589 clock_t expire_at_tick = ddi_get_lbolt() +
1592 DTRACE_PROBE3(zio__delay__hit, zio_t *, zio,
1593 hrtime_t, now, hrtime_t, diff);
1595 if (NSEC_TO_TICK(diff) == 0) {
1596 /* Our delay is less than a jiffy - just spin */
1597 zfs_sleep_until(zio->io_target_timestamp);
1600 * Use taskq_dispatch_delay() in the place of
1601 * OpenZFS's timeout_generic().
1603 tid = taskq_dispatch_delay(system_taskq,
1604 (task_func_t *)zio_interrupt,
1605 zio, TQ_NOSLEEP, expire_at_tick);
1606 if (tid == TASKQID_INVALID) {
1608 * Couldn't allocate a task. Just
1609 * finish the zio without a delay.
1618 DTRACE_PROBE1(zio__delay__skip, zio_t *, zio);
1623 * Execute the I/O pipeline until one of the following occurs:
1624 * (1) the I/O completes; (2) the pipeline stalls waiting for
1625 * dependent child I/Os; (3) the I/O issues, so we're waiting
1626 * for an I/O completion interrupt; (4) the I/O is delegated by
1627 * vdev-level caching or aggregation; (5) the I/O is deferred
1628 * due to vdev-level queueing; (6) the I/O is handed off to
1629 * another thread. In all cases, the pipeline stops whenever
1630 * there's no CPU work; it never burns a thread in cv_wait_io().
1632 * There's no locking on io_stage because there's no legitimate way
1633 * for multiple threads to be attempting to process the same I/O.
1635 static zio_pipe_stage_t *zio_pipeline[];
1638 * zio_execute() is a wrapper around the static function
1639 * __zio_execute() so that we can force __zio_execute() to be
1640 * inlined. This reduces stack overhead which is important
1641 * because __zio_execute() is called recursively in several zio
1642 * code paths. zio_execute() itself cannot be inlined because
1643 * it is externally visible.
1646 zio_execute(zio_t *zio)
1648 fstrans_cookie_t cookie;
1650 cookie = spl_fstrans_mark();
1652 spl_fstrans_unmark(cookie);
1656 * Used to determine if in the current context the stack is sized large
1657 * enough to allow zio_execute() to be called recursively. A minimum
1658 * stack size of 16K is required to avoid needing to re-dispatch the zio.
1661 zio_execute_stack_check(zio_t *zio)
1663 #if !defined(HAVE_LARGE_STACKS)
1664 dsl_pool_t *dp = spa_get_dsl(zio->io_spa);
1666 /* Executing in txg_sync_thread() context. */
1667 if (dp && curthread == dp->dp_tx.tx_sync_thread)
1670 /* Pool initialization outside of zio_taskq context. */
1671 if (dp && spa_is_initializing(dp->dp_spa) &&
1672 !zio_taskq_member(zio, ZIO_TASKQ_ISSUE) &&
1673 !zio_taskq_member(zio, ZIO_TASKQ_ISSUE_HIGH))
1675 #endif /* HAVE_LARGE_STACKS */
1680 __attribute__((always_inline))
1682 __zio_execute(zio_t *zio)
1684 zio->io_executor = curthread;
1686 ASSERT3U(zio->io_queued_timestamp, >, 0);
1688 while (zio->io_stage < ZIO_STAGE_DONE) {
1689 enum zio_stage pipeline = zio->io_pipeline;
1690 enum zio_stage stage = zio->io_stage;
1693 ASSERT(!MUTEX_HELD(&zio->io_lock));
1694 ASSERT(ISP2(stage));
1695 ASSERT(zio->io_stall == NULL);
1699 } while ((stage & pipeline) == 0);
1701 ASSERT(stage <= ZIO_STAGE_DONE);
1704 * If we are in interrupt context and this pipeline stage
1705 * will grab a config lock that is held across I/O,
1706 * or may wait for an I/O that needs an interrupt thread
1707 * to complete, issue async to avoid deadlock.
1709 * For VDEV_IO_START, we cut in line so that the io will
1710 * be sent to disk promptly.
1712 if ((stage & ZIO_BLOCKING_STAGES) && zio->io_vd == NULL &&
1713 zio_taskq_member(zio, ZIO_TASKQ_INTERRUPT)) {
1714 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ?
1715 zio_requeue_io_start_cut_in_line : B_FALSE;
1716 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut);
1721 * If the current context doesn't have large enough stacks
1722 * the zio must be issued asynchronously to prevent overflow.
1724 if (zio_execute_stack_check(zio)) {
1725 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ?
1726 zio_requeue_io_start_cut_in_line : B_FALSE;
1727 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut);
1731 zio->io_stage = stage;
1732 zio->io_pipeline_trace |= zio->io_stage;
1733 rv = zio_pipeline[highbit64(stage) - 1](zio);
1735 if (rv == ZIO_PIPELINE_STOP)
1738 ASSERT(rv == ZIO_PIPELINE_CONTINUE);
1744 * ==========================================================================
1745 * Initiate I/O, either sync or async
1746 * ==========================================================================
1749 zio_wait(zio_t *zio)
1753 ASSERT(zio->io_stage == ZIO_STAGE_OPEN);
1754 ASSERT(zio->io_executor == NULL);
1756 zio->io_waiter = curthread;
1757 ASSERT0(zio->io_queued_timestamp);
1758 zio->io_queued_timestamp = gethrtime();
1762 mutex_enter(&zio->io_lock);
1763 while (zio->io_executor != NULL)
1764 cv_wait_io(&zio->io_cv, &zio->io_lock);
1765 mutex_exit(&zio->io_lock);
1767 error = zio->io_error;
1774 zio_nowait(zio_t *zio)
1776 ASSERT(zio->io_executor == NULL);
1778 if (zio->io_child_type == ZIO_CHILD_LOGICAL &&
1779 zio_unique_parent(zio) == NULL) {
1783 * This is a logical async I/O with no parent to wait for it.
1784 * We add it to the spa_async_root_zio "Godfather" I/O which
1785 * will ensure they complete prior to unloading the pool.
1787 spa_t *spa = zio->io_spa;
1789 pio = spa->spa_async_zio_root[CPU_SEQID];
1792 zio_add_child(pio, zio);
1795 ASSERT0(zio->io_queued_timestamp);
1796 zio->io_queued_timestamp = gethrtime();
1801 * ==========================================================================
1802 * Reexecute or suspend/resume failed I/O
1803 * ==========================================================================
1807 zio_reexecute(zio_t *pio)
1809 zio_t *cio, *cio_next;
1811 zio_link_t *zl = NULL;
1813 ASSERT(pio->io_child_type == ZIO_CHILD_LOGICAL);
1814 ASSERT(pio->io_orig_stage == ZIO_STAGE_OPEN);
1815 ASSERT(pio->io_gang_leader == NULL);
1816 ASSERT(pio->io_gang_tree == NULL);
1818 pio->io_flags = pio->io_orig_flags;
1819 pio->io_stage = pio->io_orig_stage;
1820 pio->io_pipeline = pio->io_orig_pipeline;
1821 pio->io_reexecute = 0;
1822 pio->io_flags |= ZIO_FLAG_REEXECUTED;
1823 pio->io_pipeline_trace = 0;
1825 for (w = 0; w < ZIO_WAIT_TYPES; w++)
1826 pio->io_state[w] = 0;
1827 for (c = 0; c < ZIO_CHILD_TYPES; c++)
1828 pio->io_child_error[c] = 0;
1830 if (IO_IS_ALLOCATING(pio))
1831 BP_ZERO(pio->io_bp);
1834 * As we reexecute pio's children, new children could be created.
1835 * New children go to the head of pio's io_child_list, however,
1836 * so we will (correctly) not reexecute them. The key is that
1837 * the remainder of pio's io_child_list, from 'cio_next' onward,
1838 * cannot be affected by any side effects of reexecuting 'cio'.
1840 for (cio = zio_walk_children(pio, &zl); cio != NULL; cio = cio_next) {
1841 cio_next = zio_walk_children(pio, &zl);
1842 mutex_enter(&pio->io_lock);
1843 for (w = 0; w < ZIO_WAIT_TYPES; w++)
1844 pio->io_children[cio->io_child_type][w]++;
1845 mutex_exit(&pio->io_lock);
1850 * Now that all children have been reexecuted, execute the parent.
1851 * We don't reexecute "The Godfather" I/O here as it's the
1852 * responsibility of the caller to wait on it.
1854 if (!(pio->io_flags & ZIO_FLAG_GODFATHER)) {
1855 pio->io_queued_timestamp = gethrtime();
1861 zio_suspend(spa_t *spa, zio_t *zio)
1863 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC)
1864 fm_panic("Pool '%s' has encountered an uncorrectable I/O "
1865 "failure and the failure mode property for this pool "
1866 "is set to panic.", spa_name(spa));
1868 cmn_err(CE_WARN, "Pool '%s' has encountered an uncorrectable I/O "
1869 "failure and has been suspended.\n", spa_name(spa));
1871 zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, NULL, 0, 0);
1873 mutex_enter(&spa->spa_suspend_lock);
1875 if (spa->spa_suspend_zio_root == NULL)
1876 spa->spa_suspend_zio_root = zio_root(spa, NULL, NULL,
1877 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE |
1878 ZIO_FLAG_GODFATHER);
1880 spa->spa_suspended = B_TRUE;
1883 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER));
1884 ASSERT(zio != spa->spa_suspend_zio_root);
1885 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1886 ASSERT(zio_unique_parent(zio) == NULL);
1887 ASSERT(zio->io_stage == ZIO_STAGE_DONE);
1888 zio_add_child(spa->spa_suspend_zio_root, zio);
1891 mutex_exit(&spa->spa_suspend_lock);
1895 zio_resume(spa_t *spa)
1900 * Reexecute all previously suspended i/o.
1902 mutex_enter(&spa->spa_suspend_lock);
1903 spa->spa_suspended = B_FALSE;
1904 cv_broadcast(&spa->spa_suspend_cv);
1905 pio = spa->spa_suspend_zio_root;
1906 spa->spa_suspend_zio_root = NULL;
1907 mutex_exit(&spa->spa_suspend_lock);
1913 return (zio_wait(pio));
1917 zio_resume_wait(spa_t *spa)
1919 mutex_enter(&spa->spa_suspend_lock);
1920 while (spa_suspended(spa))
1921 cv_wait(&spa->spa_suspend_cv, &spa->spa_suspend_lock);
1922 mutex_exit(&spa->spa_suspend_lock);
1926 * ==========================================================================
1929 * A gang block is a collection of small blocks that looks to the DMU
1930 * like one large block. When zio_dva_allocate() cannot find a block
1931 * of the requested size, due to either severe fragmentation or the pool
1932 * being nearly full, it calls zio_write_gang_block() to construct the
1933 * block from smaller fragments.
1935 * A gang block consists of a gang header (zio_gbh_phys_t) and up to
1936 * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like
1937 * an indirect block: it's an array of block pointers. It consumes
1938 * only one sector and hence is allocatable regardless of fragmentation.
1939 * The gang header's bps point to its gang members, which hold the data.
1941 * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg>
1942 * as the verifier to ensure uniqueness of the SHA256 checksum.
1943 * Critically, the gang block bp's blk_cksum is the checksum of the data,
1944 * not the gang header. This ensures that data block signatures (needed for
1945 * deduplication) are independent of how the block is physically stored.
1947 * Gang blocks can be nested: a gang member may itself be a gang block.
1948 * Thus every gang block is a tree in which root and all interior nodes are
1949 * gang headers, and the leaves are normal blocks that contain user data.
1950 * The root of the gang tree is called the gang leader.
1952 * To perform any operation (read, rewrite, free, claim) on a gang block,
1953 * zio_gang_assemble() first assembles the gang tree (minus data leaves)
1954 * in the io_gang_tree field of the original logical i/o by recursively
1955 * reading the gang leader and all gang headers below it. This yields
1956 * an in-core tree containing the contents of every gang header and the
1957 * bps for every constituent of the gang block.
1959 * With the gang tree now assembled, zio_gang_issue() just walks the gang tree
1960 * and invokes a callback on each bp. To free a gang block, zio_gang_issue()
1961 * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp.
1962 * zio_claim_gang() provides a similarly trivial wrapper for zio_claim().
1963 * zio_read_gang() is a wrapper around zio_read() that omits reading gang
1964 * headers, since we already have those in io_gang_tree. zio_rewrite_gang()
1965 * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite()
1966 * of the gang header plus zio_checksum_compute() of the data to update the
1967 * gang header's blk_cksum as described above.
1969 * The two-phase assemble/issue model solves the problem of partial failure --
1970 * what if you'd freed part of a gang block but then couldn't read the
1971 * gang header for another part? Assembling the entire gang tree first
1972 * ensures that all the necessary gang header I/O has succeeded before
1973 * starting the actual work of free, claim, or write. Once the gang tree
1974 * is assembled, free and claim are in-memory operations that cannot fail.
1976 * In the event that a gang write fails, zio_dva_unallocate() walks the
1977 * gang tree to immediately free (i.e. insert back into the space map)
1978 * everything we've allocated. This ensures that we don't get ENOSPC
1979 * errors during repeated suspend/resume cycles due to a flaky device.
1981 * Gang rewrites only happen during sync-to-convergence. If we can't assemble
1982 * the gang tree, we won't modify the block, so we can safely defer the free
1983 * (knowing that the block is still intact). If we *can* assemble the gang
1984 * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free
1985 * each constituent bp and we can allocate a new block on the next sync pass.
1987 * In all cases, the gang tree allows complete recovery from partial failure.
1988 * ==========================================================================
1992 zio_gang_issue_func_done(zio_t *zio)
1994 abd_put(zio->io_abd);
1998 zio_read_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data,
2004 return (zio_read(pio, pio->io_spa, bp, abd_get_offset(data, offset),
2005 BP_GET_PSIZE(bp), zio_gang_issue_func_done,
2006 NULL, pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
2007 &pio->io_bookmark));
2011 zio_rewrite_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data,
2018 abd_get_from_buf(gn->gn_gbh, SPA_GANGBLOCKSIZE);
2019 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
2020 gbh_abd, SPA_GANGBLOCKSIZE, zio_gang_issue_func_done, NULL,
2021 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
2024 * As we rewrite each gang header, the pipeline will compute
2025 * a new gang block header checksum for it; but no one will
2026 * compute a new data checksum, so we do that here. The one
2027 * exception is the gang leader: the pipeline already computed
2028 * its data checksum because that stage precedes gang assembly.
2029 * (Presently, nothing actually uses interior data checksums;
2030 * this is just good hygiene.)
2032 if (gn != pio->io_gang_leader->io_gang_tree) {
2033 abd_t *buf = abd_get_offset(data, offset);
2035 zio_checksum_compute(zio, BP_GET_CHECKSUM(bp),
2036 buf, BP_GET_PSIZE(bp));
2041 * If we are here to damage data for testing purposes,
2042 * leave the GBH alone so that we can detect the damage.
2044 if (pio->io_gang_leader->io_flags & ZIO_FLAG_INDUCE_DAMAGE)
2045 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES;
2047 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
2048 abd_get_offset(data, offset), BP_GET_PSIZE(bp),
2049 zio_gang_issue_func_done, NULL, pio->io_priority,
2050 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
2058 zio_free_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data,
2061 return (zio_free_sync(pio, pio->io_spa, pio->io_txg, bp,
2062 ZIO_GANG_CHILD_FLAGS(pio)));
2067 zio_claim_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, abd_t *data,
2070 return (zio_claim(pio, pio->io_spa, pio->io_txg, bp,
2071 NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio)));
2074 static zio_gang_issue_func_t *zio_gang_issue_func[ZIO_TYPES] = {
2083 static void zio_gang_tree_assemble_done(zio_t *zio);
2085 static zio_gang_node_t *
2086 zio_gang_node_alloc(zio_gang_node_t **gnpp)
2088 zio_gang_node_t *gn;
2090 ASSERT(*gnpp == NULL);
2092 gn = kmem_zalloc(sizeof (*gn), KM_SLEEP);
2093 gn->gn_gbh = zio_buf_alloc(SPA_GANGBLOCKSIZE);
2100 zio_gang_node_free(zio_gang_node_t **gnpp)
2102 zio_gang_node_t *gn = *gnpp;
2105 for (g = 0; g < SPA_GBH_NBLKPTRS; g++)
2106 ASSERT(gn->gn_child[g] == NULL);
2108 zio_buf_free(gn->gn_gbh, SPA_GANGBLOCKSIZE);
2109 kmem_free(gn, sizeof (*gn));
2114 zio_gang_tree_free(zio_gang_node_t **gnpp)
2116 zio_gang_node_t *gn = *gnpp;
2122 for (g = 0; g < SPA_GBH_NBLKPTRS; g++)
2123 zio_gang_tree_free(&gn->gn_child[g]);
2125 zio_gang_node_free(gnpp);
2129 zio_gang_tree_assemble(zio_t *gio, blkptr_t *bp, zio_gang_node_t **gnpp)
2131 zio_gang_node_t *gn = zio_gang_node_alloc(gnpp);
2132 abd_t *gbh_abd = abd_get_from_buf(gn->gn_gbh, SPA_GANGBLOCKSIZE);
2134 ASSERT(gio->io_gang_leader == gio);
2135 ASSERT(BP_IS_GANG(bp));
2137 zio_nowait(zio_read(gio, gio->io_spa, bp, gbh_abd, SPA_GANGBLOCKSIZE,
2138 zio_gang_tree_assemble_done, gn, gio->io_priority,
2139 ZIO_GANG_CHILD_FLAGS(gio), &gio->io_bookmark));
2143 zio_gang_tree_assemble_done(zio_t *zio)
2145 zio_t *gio = zio->io_gang_leader;
2146 zio_gang_node_t *gn = zio->io_private;
2147 blkptr_t *bp = zio->io_bp;
2150 ASSERT(gio == zio_unique_parent(zio));
2151 ASSERT(zio->io_child_count == 0);
2156 /* this ABD was created from a linear buf in zio_gang_tree_assemble */
2157 if (BP_SHOULD_BYTESWAP(bp))
2158 byteswap_uint64_array(abd_to_buf(zio->io_abd), zio->io_size);
2160 ASSERT3P(abd_to_buf(zio->io_abd), ==, gn->gn_gbh);
2161 ASSERT(zio->io_size == SPA_GANGBLOCKSIZE);
2162 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC);
2164 abd_put(zio->io_abd);
2166 for (g = 0; g < SPA_GBH_NBLKPTRS; g++) {
2167 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
2168 if (!BP_IS_GANG(gbp))
2170 zio_gang_tree_assemble(gio, gbp, &gn->gn_child[g]);
2175 zio_gang_tree_issue(zio_t *pio, zio_gang_node_t *gn, blkptr_t *bp, abd_t *data,
2178 zio_t *gio = pio->io_gang_leader;
2182 ASSERT(BP_IS_GANG(bp) == !!gn);
2183 ASSERT(BP_GET_CHECKSUM(bp) == BP_GET_CHECKSUM(gio->io_bp));
2184 ASSERT(BP_GET_LSIZE(bp) == BP_GET_PSIZE(bp) || gn == gio->io_gang_tree);
2187 * If you're a gang header, your data is in gn->gn_gbh.
2188 * If you're a gang member, your data is in 'data' and gn == NULL.
2190 zio = zio_gang_issue_func[gio->io_type](pio, bp, gn, data, offset);
2193 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC);
2195 for (g = 0; g < SPA_GBH_NBLKPTRS; g++) {
2196 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
2197 if (BP_IS_HOLE(gbp))
2199 zio_gang_tree_issue(zio, gn->gn_child[g], gbp, data,
2201 offset += BP_GET_PSIZE(gbp);
2205 if (gn == gio->io_gang_tree)
2206 ASSERT3U(gio->io_size, ==, offset);
2213 zio_gang_assemble(zio_t *zio)
2215 blkptr_t *bp = zio->io_bp;
2217 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == NULL);
2218 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
2220 zio->io_gang_leader = zio;
2222 zio_gang_tree_assemble(zio, bp, &zio->io_gang_tree);
2224 return (ZIO_PIPELINE_CONTINUE);
2228 zio_gang_issue(zio_t *zio)
2230 blkptr_t *bp = zio->io_bp;
2232 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE))
2233 return (ZIO_PIPELINE_STOP);
2235 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == zio);
2236 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
2238 if (zio->io_child_error[ZIO_CHILD_GANG] == 0)
2239 zio_gang_tree_issue(zio, zio->io_gang_tree, bp, zio->io_abd,
2242 zio_gang_tree_free(&zio->io_gang_tree);
2244 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
2246 return (ZIO_PIPELINE_CONTINUE);
2250 zio_write_gang_member_ready(zio_t *zio)
2252 zio_t *pio = zio_unique_parent(zio);
2253 dva_t *cdva = zio->io_bp->blk_dva;
2254 dva_t *pdva = pio->io_bp->blk_dva;
2257 ASSERTV(zio_t *gio = zio->io_gang_leader);
2259 if (BP_IS_HOLE(zio->io_bp))
2262 ASSERT(BP_IS_HOLE(&zio->io_bp_orig));
2264 ASSERT(zio->io_child_type == ZIO_CHILD_GANG);
2265 ASSERT3U(zio->io_prop.zp_copies, ==, gio->io_prop.zp_copies);
2266 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(zio->io_bp));
2267 ASSERT3U(pio->io_prop.zp_copies, <=, BP_GET_NDVAS(pio->io_bp));
2268 ASSERT3U(BP_GET_NDVAS(zio->io_bp), <=, BP_GET_NDVAS(pio->io_bp));
2270 mutex_enter(&pio->io_lock);
2271 for (d = 0; d < BP_GET_NDVAS(zio->io_bp); d++) {
2272 ASSERT(DVA_GET_GANG(&pdva[d]));
2273 asize = DVA_GET_ASIZE(&pdva[d]);
2274 asize += DVA_GET_ASIZE(&cdva[d]);
2275 DVA_SET_ASIZE(&pdva[d], asize);
2277 mutex_exit(&pio->io_lock);
2281 zio_write_gang_done(zio_t *zio)
2283 abd_put(zio->io_abd);
2287 zio_write_gang_block(zio_t *pio)
2289 spa_t *spa = pio->io_spa;
2290 metaslab_class_t *mc = spa_normal_class(spa);
2291 blkptr_t *bp = pio->io_bp;
2292 zio_t *gio = pio->io_gang_leader;
2294 zio_gang_node_t *gn, **gnpp;
2295 zio_gbh_phys_t *gbh;
2297 uint64_t txg = pio->io_txg;
2298 uint64_t resid = pio->io_size;
2300 int copies = gio->io_prop.zp_copies;
2301 int gbh_copies = MIN(copies + 1, spa_max_replication(spa));
2305 int flags = METASLAB_HINTBP_FAVOR | METASLAB_GANG_HEADER;
2306 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) {
2307 ASSERT(pio->io_priority == ZIO_PRIORITY_ASYNC_WRITE);
2308 ASSERT(!(pio->io_flags & ZIO_FLAG_NODATA));
2310 flags |= METASLAB_ASYNC_ALLOC;
2311 VERIFY(refcount_held(&mc->mc_alloc_slots, pio));
2314 * The logical zio has already placed a reservation for
2315 * 'copies' allocation slots but gang blocks may require
2316 * additional copies. These additional copies
2317 * (i.e. gbh_copies - copies) are guaranteed to succeed
2318 * since metaslab_class_throttle_reserve() always allows
2319 * additional reservations for gang blocks.
2321 VERIFY(metaslab_class_throttle_reserve(mc, gbh_copies - copies,
2325 error = metaslab_alloc(spa, mc, SPA_GANGBLOCKSIZE,
2326 bp, gbh_copies, txg, pio == gio ? NULL : gio->io_bp, flags,
2327 &pio->io_alloc_list, pio);
2329 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) {
2330 ASSERT(pio->io_priority == ZIO_PRIORITY_ASYNC_WRITE);
2331 ASSERT(!(pio->io_flags & ZIO_FLAG_NODATA));
2334 * If we failed to allocate the gang block header then
2335 * we remove any additional allocation reservations that
2336 * we placed here. The original reservation will
2337 * be removed when the logical I/O goes to the ready
2340 metaslab_class_throttle_unreserve(mc,
2341 gbh_copies - copies, pio);
2344 pio->io_error = error;
2345 return (ZIO_PIPELINE_CONTINUE);
2349 gnpp = &gio->io_gang_tree;
2351 gnpp = pio->io_private;
2352 ASSERT(pio->io_ready == zio_write_gang_member_ready);
2355 gn = zio_gang_node_alloc(gnpp);
2357 bzero(gbh, SPA_GANGBLOCKSIZE);
2358 gbh_abd = abd_get_from_buf(gbh, SPA_GANGBLOCKSIZE);
2361 * Create the gang header.
2363 zio = zio_rewrite(pio, spa, txg, bp, gbh_abd, SPA_GANGBLOCKSIZE,
2364 zio_write_gang_done, NULL, pio->io_priority,
2365 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
2368 * Create and nowait the gang children.
2370 for (g = 0; resid != 0; resid -= lsize, g++) {
2373 lsize = P2ROUNDUP(resid / (SPA_GBH_NBLKPTRS - g),
2375 ASSERT(lsize >= SPA_MINBLOCKSIZE && lsize <= resid);
2377 zp.zp_checksum = gio->io_prop.zp_checksum;
2378 zp.zp_compress = ZIO_COMPRESS_OFF;
2379 zp.zp_type = DMU_OT_NONE;
2381 zp.zp_copies = gio->io_prop.zp_copies;
2382 zp.zp_dedup = B_FALSE;
2383 zp.zp_dedup_verify = B_FALSE;
2384 zp.zp_nopwrite = B_FALSE;
2386 cio = zio_write(zio, spa, txg, &gbh->zg_blkptr[g],
2387 abd_get_offset(pio->io_abd, pio->io_size - resid), lsize,
2388 lsize, &zp, zio_write_gang_member_ready, NULL, NULL,
2389 zio_write_gang_done, &gn->gn_child[g], pio->io_priority,
2390 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
2392 if (pio->io_flags & ZIO_FLAG_IO_ALLOCATING) {
2393 ASSERT(pio->io_priority == ZIO_PRIORITY_ASYNC_WRITE);
2394 ASSERT(!(pio->io_flags & ZIO_FLAG_NODATA));
2397 * Gang children won't throttle but we should
2398 * account for their work, so reserve an allocation
2399 * slot for them here.
2401 VERIFY(metaslab_class_throttle_reserve(mc,
2402 zp.zp_copies, cio, flags));
2408 * Set pio's pipeline to just wait for zio to finish.
2410 pio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
2413 * We didn't allocate this bp, so make sure it doesn't get unmarked.
2415 pio->io_flags &= ~ZIO_FLAG_FASTWRITE;
2419 return (ZIO_PIPELINE_CONTINUE);
2423 * The zio_nop_write stage in the pipeline determines if allocating a
2424 * new bp is necessary. The nopwrite feature can handle writes in
2425 * either syncing or open context (i.e. zil writes) and as a result is
2426 * mutually exclusive with dedup.
2428 * By leveraging a cryptographically secure checksum, such as SHA256, we
2429 * can compare the checksums of the new data and the old to determine if
2430 * allocating a new block is required. Note that our requirements for
2431 * cryptographic strength are fairly weak: there can't be any accidental
2432 * hash collisions, but we don't need to be secure against intentional
2433 * (malicious) collisions. To trigger a nopwrite, you have to be able
2434 * to write the file to begin with, and triggering an incorrect (hash
2435 * collision) nopwrite is no worse than simply writing to the file.
2436 * That said, there are no known attacks against the checksum algorithms
2437 * used for nopwrite, assuming that the salt and the checksums
2438 * themselves remain secret.
2441 zio_nop_write(zio_t *zio)
2443 blkptr_t *bp = zio->io_bp;
2444 blkptr_t *bp_orig = &zio->io_bp_orig;
2445 zio_prop_t *zp = &zio->io_prop;
2447 ASSERT(BP_GET_LEVEL(bp) == 0);
2448 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
2449 ASSERT(zp->zp_nopwrite);
2450 ASSERT(!zp->zp_dedup);
2451 ASSERT(zio->io_bp_override == NULL);
2452 ASSERT(IO_IS_ALLOCATING(zio));
2455 * Check to see if the original bp and the new bp have matching
2456 * characteristics (i.e. same checksum, compression algorithms, etc).
2457 * If they don't then just continue with the pipeline which will
2458 * allocate a new bp.
2460 if (BP_IS_HOLE(bp_orig) ||
2461 !(zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_flags &
2462 ZCHECKSUM_FLAG_NOPWRITE) ||
2463 BP_GET_CHECKSUM(bp) != BP_GET_CHECKSUM(bp_orig) ||
2464 BP_GET_COMPRESS(bp) != BP_GET_COMPRESS(bp_orig) ||
2465 BP_GET_DEDUP(bp) != BP_GET_DEDUP(bp_orig) ||
2466 zp->zp_copies != BP_GET_NDVAS(bp_orig))
2467 return (ZIO_PIPELINE_CONTINUE);
2470 * If the checksums match then reset the pipeline so that we
2471 * avoid allocating a new bp and issuing any I/O.
2473 if (ZIO_CHECKSUM_EQUAL(bp->blk_cksum, bp_orig->blk_cksum)) {
2474 ASSERT(zio_checksum_table[zp->zp_checksum].ci_flags &
2475 ZCHECKSUM_FLAG_NOPWRITE);
2476 ASSERT3U(BP_GET_PSIZE(bp), ==, BP_GET_PSIZE(bp_orig));
2477 ASSERT3U(BP_GET_LSIZE(bp), ==, BP_GET_LSIZE(bp_orig));
2478 ASSERT(zp->zp_compress != ZIO_COMPRESS_OFF);
2479 ASSERT(bcmp(&bp->blk_prop, &bp_orig->blk_prop,
2480 sizeof (uint64_t)) == 0);
2483 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
2484 zio->io_flags |= ZIO_FLAG_NOPWRITE;
2487 return (ZIO_PIPELINE_CONTINUE);
2491 * ==========================================================================
2493 * ==========================================================================
2496 zio_ddt_child_read_done(zio_t *zio)
2498 blkptr_t *bp = zio->io_bp;
2499 ddt_entry_t *dde = zio->io_private;
2501 zio_t *pio = zio_unique_parent(zio);
2503 mutex_enter(&pio->io_lock);
2504 ddp = ddt_phys_select(dde, bp);
2505 if (zio->io_error == 0)
2506 ddt_phys_clear(ddp); /* this ddp doesn't need repair */
2508 if (zio->io_error == 0 && dde->dde_repair_abd == NULL)
2509 dde->dde_repair_abd = zio->io_abd;
2511 abd_free(zio->io_abd);
2512 mutex_exit(&pio->io_lock);
2516 zio_ddt_read_start(zio_t *zio)
2518 blkptr_t *bp = zio->io_bp;
2521 ASSERT(BP_GET_DEDUP(bp));
2522 ASSERT(BP_GET_PSIZE(bp) == zio->io_size);
2523 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
2525 if (zio->io_child_error[ZIO_CHILD_DDT]) {
2526 ddt_t *ddt = ddt_select(zio->io_spa, bp);
2527 ddt_entry_t *dde = ddt_repair_start(ddt, bp);
2528 ddt_phys_t *ddp = dde->dde_phys;
2529 ddt_phys_t *ddp_self = ddt_phys_select(dde, bp);
2532 ASSERT(zio->io_vsd == NULL);
2535 if (ddp_self == NULL)
2536 return (ZIO_PIPELINE_CONTINUE);
2538 for (p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
2539 if (ddp->ddp_phys_birth == 0 || ddp == ddp_self)
2541 ddt_bp_create(ddt->ddt_checksum, &dde->dde_key, ddp,
2543 zio_nowait(zio_read(zio, zio->io_spa, &blk,
2544 abd_alloc_for_io(zio->io_size, B_TRUE),
2545 zio->io_size, zio_ddt_child_read_done, dde,
2546 zio->io_priority, ZIO_DDT_CHILD_FLAGS(zio) |
2547 ZIO_FLAG_DONT_PROPAGATE, &zio->io_bookmark));
2549 return (ZIO_PIPELINE_CONTINUE);
2552 zio_nowait(zio_read(zio, zio->io_spa, bp,
2553 zio->io_abd, zio->io_size, NULL, NULL, zio->io_priority,
2554 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark));
2556 return (ZIO_PIPELINE_CONTINUE);
2560 zio_ddt_read_done(zio_t *zio)
2562 blkptr_t *bp = zio->io_bp;
2564 if (zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE))
2565 return (ZIO_PIPELINE_STOP);
2567 ASSERT(BP_GET_DEDUP(bp));
2568 ASSERT(BP_GET_PSIZE(bp) == zio->io_size);
2569 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
2571 if (zio->io_child_error[ZIO_CHILD_DDT]) {
2572 ddt_t *ddt = ddt_select(zio->io_spa, bp);
2573 ddt_entry_t *dde = zio->io_vsd;
2575 ASSERT(spa_load_state(zio->io_spa) != SPA_LOAD_NONE);
2576 return (ZIO_PIPELINE_CONTINUE);
2579 zio->io_stage = ZIO_STAGE_DDT_READ_START >> 1;
2580 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE);
2581 return (ZIO_PIPELINE_STOP);
2583 if (dde->dde_repair_abd != NULL) {
2584 abd_copy(zio->io_abd, dde->dde_repair_abd,
2586 zio->io_child_error[ZIO_CHILD_DDT] = 0;
2588 ddt_repair_done(ddt, dde);
2592 ASSERT(zio->io_vsd == NULL);
2594 return (ZIO_PIPELINE_CONTINUE);
2598 zio_ddt_collision(zio_t *zio, ddt_t *ddt, ddt_entry_t *dde)
2600 spa_t *spa = zio->io_spa;
2602 boolean_t do_raw = !!(zio->io_flags & ZIO_FLAG_RAW);
2604 ASSERT(!(zio->io_bp_override && do_raw));
2607 * Note: we compare the original data, not the transformed data,
2608 * because when zio->io_bp is an override bp, we will not have
2609 * pushed the I/O transforms. That's an important optimization
2610 * because otherwise we'd compress/encrypt all dmu_sync() data twice.
2611 * However, we should never get a raw, override zio so in these
2612 * cases we can compare the io_data directly. This is useful because
2613 * it allows us to do dedup verification even if we don't have access
2614 * to the original data (for instance, if the encryption keys aren't
2618 for (p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) {
2619 zio_t *lio = dde->dde_lead_zio[p];
2621 if (lio != NULL && do_raw) {
2622 return (lio->io_size != zio->io_size ||
2623 abd_cmp(zio->io_abd, lio->io_abd) != 0);
2624 } else if (lio != NULL) {
2625 return (lio->io_orig_size != zio->io_orig_size ||
2626 abd_cmp(zio->io_orig_abd, lio->io_orig_abd) != 0);
2630 for (p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) {
2631 ddt_phys_t *ddp = &dde->dde_phys[p];
2633 if (ddp->ddp_phys_birth != 0 && do_raw) {
2634 blkptr_t blk = *zio->io_bp;
2639 ddt_bp_fill(ddp, &blk, ddp->ddp_phys_birth);
2640 psize = BP_GET_PSIZE(&blk);
2642 if (psize != zio->io_size)
2647 tmpabd = abd_alloc_for_io(psize, B_TRUE);
2649 error = zio_wait(zio_read(NULL, spa, &blk, tmpabd,
2650 psize, NULL, NULL, ZIO_PRIORITY_SYNC_READ,
2651 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE |
2652 ZIO_FLAG_RAW, &zio->io_bookmark));
2655 if (abd_cmp(tmpabd, zio->io_abd) != 0)
2656 error = SET_ERROR(ENOENT);
2661 return (error != 0);
2662 } else if (ddp->ddp_phys_birth != 0) {
2663 arc_buf_t *abuf = NULL;
2664 arc_flags_t aflags = ARC_FLAG_WAIT;
2665 blkptr_t blk = *zio->io_bp;
2668 ddt_bp_fill(ddp, &blk, ddp->ddp_phys_birth);
2670 if (BP_GET_LSIZE(&blk) != zio->io_orig_size)
2675 error = arc_read(NULL, spa, &blk,
2676 arc_getbuf_func, &abuf, ZIO_PRIORITY_SYNC_READ,
2677 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE,
2678 &aflags, &zio->io_bookmark);
2681 if (abd_cmp_buf(zio->io_orig_abd, abuf->b_data,
2682 zio->io_orig_size) != 0)
2683 error = SET_ERROR(ENOENT);
2684 arc_buf_destroy(abuf, &abuf);
2688 return (error != 0);
2696 zio_ddt_child_write_ready(zio_t *zio)
2698 int p = zio->io_prop.zp_copies;
2699 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp);
2700 ddt_entry_t *dde = zio->io_private;
2701 ddt_phys_t *ddp = &dde->dde_phys[p];
2710 ASSERT(dde->dde_lead_zio[p] == zio);
2712 ddt_phys_fill(ddp, zio->io_bp);
2715 while ((pio = zio_walk_parents(zio, &zl)) != NULL)
2716 ddt_bp_fill(ddp, pio->io_bp, zio->io_txg);
2722 zio_ddt_child_write_done(zio_t *zio)
2724 int p = zio->io_prop.zp_copies;
2725 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp);
2726 ddt_entry_t *dde = zio->io_private;
2727 ddt_phys_t *ddp = &dde->dde_phys[p];
2731 ASSERT(ddp->ddp_refcnt == 0);
2732 ASSERT(dde->dde_lead_zio[p] == zio);
2733 dde->dde_lead_zio[p] = NULL;
2735 if (zio->io_error == 0) {
2736 zio_link_t *zl = NULL;
2737 while (zio_walk_parents(zio, &zl) != NULL)
2738 ddt_phys_addref(ddp);
2740 ddt_phys_clear(ddp);
2747 zio_ddt_ditto_write_done(zio_t *zio)
2749 int p = DDT_PHYS_DITTO;
2750 blkptr_t *bp = zio->io_bp;
2751 ddt_t *ddt = ddt_select(zio->io_spa, bp);
2752 ddt_entry_t *dde = zio->io_private;
2753 ddt_phys_t *ddp = &dde->dde_phys[p];
2754 ddt_key_t *ddk = &dde->dde_key;
2755 ASSERTV(zio_prop_t *zp = &zio->io_prop);
2759 ASSERT(ddp->ddp_refcnt == 0);
2760 ASSERT(dde->dde_lead_zio[p] == zio);
2761 dde->dde_lead_zio[p] = NULL;
2763 if (zio->io_error == 0) {
2764 ASSERT(ZIO_CHECKSUM_EQUAL(bp->blk_cksum, ddk->ddk_cksum));
2765 ASSERT(zp->zp_copies < SPA_DVAS_PER_BP);
2766 ASSERT(zp->zp_copies == BP_GET_NDVAS(bp) - BP_IS_GANG(bp));
2767 if (ddp->ddp_phys_birth != 0)
2768 ddt_phys_free(ddt, ddk, ddp, zio->io_txg);
2769 ddt_phys_fill(ddp, bp);
2776 zio_ddt_write(zio_t *zio)
2778 spa_t *spa = zio->io_spa;
2779 blkptr_t *bp = zio->io_bp;
2780 uint64_t txg = zio->io_txg;
2781 zio_prop_t *zp = &zio->io_prop;
2782 int p = zp->zp_copies;
2786 ddt_t *ddt = ddt_select(spa, bp);
2790 ASSERT(BP_GET_DEDUP(bp));
2791 ASSERT(BP_GET_CHECKSUM(bp) == zp->zp_checksum);
2792 ASSERT(BP_IS_HOLE(bp) || zio->io_bp_override);
2793 ASSERT(!(zio->io_bp_override && (zio->io_flags & ZIO_FLAG_RAW)));
2796 dde = ddt_lookup(ddt, bp, B_TRUE);
2797 ddp = &dde->dde_phys[p];
2799 if (zp->zp_dedup_verify && zio_ddt_collision(zio, ddt, dde)) {
2801 * If we're using a weak checksum, upgrade to a strong checksum
2802 * and try again. If we're already using a strong checksum,
2803 * we can't resolve it, so just convert to an ordinary write.
2804 * (And automatically e-mail a paper to Nature?)
2806 if (!(zio_checksum_table[zp->zp_checksum].ci_flags &
2807 ZCHECKSUM_FLAG_DEDUP)) {
2808 zp->zp_checksum = spa_dedup_checksum(spa);
2809 zio_pop_transforms(zio);
2810 zio->io_stage = ZIO_STAGE_OPEN;
2813 zp->zp_dedup = B_FALSE;
2815 zio->io_pipeline = ZIO_WRITE_PIPELINE;
2817 return (ZIO_PIPELINE_CONTINUE);
2820 ditto_copies = ddt_ditto_copies_needed(ddt, dde, ddp);
2821 ASSERT(ditto_copies < SPA_DVAS_PER_BP);
2823 if (ditto_copies > ddt_ditto_copies_present(dde) &&
2824 dde->dde_lead_zio[DDT_PHYS_DITTO] == NULL) {
2825 zio_prop_t czp = *zp;
2827 czp.zp_copies = ditto_copies;
2830 * If we arrived here with an override bp, we won't have run
2831 * the transform stack, so we won't have the data we need to
2832 * generate a child i/o. So, toss the override bp and restart.
2833 * This is safe, because using the override bp is just an
2834 * optimization; and it's rare, so the cost doesn't matter.
2836 if (zio->io_bp_override) {
2837 zio_pop_transforms(zio);
2838 zio->io_stage = ZIO_STAGE_OPEN;
2839 zio->io_pipeline = ZIO_WRITE_PIPELINE;
2840 zio->io_bp_override = NULL;
2843 return (ZIO_PIPELINE_CONTINUE);
2846 dio = zio_write(zio, spa, txg, bp, zio->io_orig_abd,
2847 zio->io_orig_size, zio->io_orig_size, &czp, NULL, NULL,
2848 NULL, zio_ddt_ditto_write_done, dde, zio->io_priority,
2849 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);
2851 zio_push_transform(dio, zio->io_abd, zio->io_size, 0, NULL);
2852 dde->dde_lead_zio[DDT_PHYS_DITTO] = dio;
2855 if (ddp->ddp_phys_birth != 0 || dde->dde_lead_zio[p] != NULL) {
2856 if (ddp->ddp_phys_birth != 0)
2857 ddt_bp_fill(ddp, bp, txg);
2858 if (dde->dde_lead_zio[p] != NULL)
2859 zio_add_child(zio, dde->dde_lead_zio[p]);
2861 ddt_phys_addref(ddp);
2862 } else if (zio->io_bp_override) {
2863 ASSERT(bp->blk_birth == txg);
2864 ASSERT(BP_EQUAL(bp, zio->io_bp_override));
2865 ddt_phys_fill(ddp, bp);
2866 ddt_phys_addref(ddp);
2868 cio = zio_write(zio, spa, txg, bp, zio->io_orig_abd,
2869 zio->io_orig_size, zio->io_orig_size, zp,
2870 zio_ddt_child_write_ready, NULL, NULL,
2871 zio_ddt_child_write_done, dde, zio->io_priority,
2872 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);
2874 zio_push_transform(cio, zio->io_abd, zio->io_size, 0, NULL);
2875 dde->dde_lead_zio[p] = cio;
2885 return (ZIO_PIPELINE_CONTINUE);
2888 ddt_entry_t *freedde; /* for debugging */
2891 zio_ddt_free(zio_t *zio)
2893 spa_t *spa = zio->io_spa;
2894 blkptr_t *bp = zio->io_bp;
2895 ddt_t *ddt = ddt_select(spa, bp);
2899 ASSERT(BP_GET_DEDUP(bp));
2900 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
2903 freedde = dde = ddt_lookup(ddt, bp, B_TRUE);
2905 ddp = ddt_phys_select(dde, bp);
2907 ddt_phys_decref(ddp);
2911 return (ZIO_PIPELINE_CONTINUE);
2915 * ==========================================================================
2916 * Allocate and free blocks
2917 * ==========================================================================
2921 zio_io_to_allocate(spa_t *spa)
2925 ASSERT(MUTEX_HELD(&spa->spa_alloc_lock));
2927 zio = avl_first(&spa->spa_alloc_tree);
2931 ASSERT(IO_IS_ALLOCATING(zio));
2934 * Try to place a reservation for this zio. If we're unable to
2935 * reserve then we throttle.
2937 if (!metaslab_class_throttle_reserve(spa_normal_class(spa),
2938 zio->io_prop.zp_copies, zio, 0)) {
2942 avl_remove(&spa->spa_alloc_tree, zio);
2943 ASSERT3U(zio->io_stage, <, ZIO_STAGE_DVA_ALLOCATE);
2949 zio_dva_throttle(zio_t *zio)
2951 spa_t *spa = zio->io_spa;
2954 if (zio->io_priority == ZIO_PRIORITY_SYNC_WRITE ||
2955 !spa_normal_class(zio->io_spa)->mc_alloc_throttle_enabled ||
2956 zio->io_child_type == ZIO_CHILD_GANG ||
2957 zio->io_flags & ZIO_FLAG_NODATA) {
2958 return (ZIO_PIPELINE_CONTINUE);
2961 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
2963 ASSERT3U(zio->io_queued_timestamp, >, 0);
2964 ASSERT(zio->io_stage == ZIO_STAGE_DVA_THROTTLE);
2966 mutex_enter(&spa->spa_alloc_lock);
2968 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
2969 avl_add(&spa->spa_alloc_tree, zio);
2971 nio = zio_io_to_allocate(zio->io_spa);
2972 mutex_exit(&spa->spa_alloc_lock);
2975 return (ZIO_PIPELINE_CONTINUE);
2978 ASSERT(nio->io_stage == ZIO_STAGE_DVA_THROTTLE);
2980 * We are passing control to a new zio so make sure that
2981 * it is processed by a different thread. We do this to
2982 * avoid stack overflows that can occur when parents are
2983 * throttled and children are making progress. We allow
2984 * it to go to the head of the taskq since it's already
2987 zio_taskq_dispatch(nio, ZIO_TASKQ_ISSUE, B_TRUE);
2989 return (ZIO_PIPELINE_STOP);
2993 zio_allocate_dispatch(spa_t *spa)
2997 mutex_enter(&spa->spa_alloc_lock);
2998 zio = zio_io_to_allocate(spa);
2999 mutex_exit(&spa->spa_alloc_lock);
3003 ASSERT3U(zio->io_stage, ==, ZIO_STAGE_DVA_THROTTLE);
3004 ASSERT0(zio->io_error);
3005 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_TRUE);
3009 zio_dva_allocate(zio_t *zio)
3011 spa_t *spa = zio->io_spa;
3012 metaslab_class_t *mc = spa_normal_class(spa);
3013 blkptr_t *bp = zio->io_bp;
3017 if (zio->io_gang_leader == NULL) {
3018 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
3019 zio->io_gang_leader = zio;
3022 ASSERT(BP_IS_HOLE(bp));
3023 ASSERT0(BP_GET_NDVAS(bp));
3024 ASSERT3U(zio->io_prop.zp_copies, >, 0);
3025 ASSERT3U(zio->io_prop.zp_copies, <=, spa_max_replication(spa));
3026 ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp));
3028 flags |= (zio->io_flags & ZIO_FLAG_FASTWRITE) ? METASLAB_FASTWRITE : 0;
3029 if (zio->io_flags & ZIO_FLAG_NODATA)
3030 flags |= METASLAB_DONT_THROTTLE;
3031 if (zio->io_flags & ZIO_FLAG_GANG_CHILD)
3032 flags |= METASLAB_GANG_CHILD;
3033 if (zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE)
3034 flags |= METASLAB_ASYNC_ALLOC;
3036 error = metaslab_alloc(spa, mc, zio->io_size, bp,
3037 zio->io_prop.zp_copies, zio->io_txg, NULL, flags,
3038 &zio->io_alloc_list, zio);
3041 spa_dbgmsg(spa, "%s: metaslab allocation failure: zio %p, "
3042 "size %llu, error %d", spa_name(spa), zio, zio->io_size,
3044 if (error == ENOSPC && zio->io_size > SPA_MINBLOCKSIZE)
3045 return (zio_write_gang_block(zio));
3046 zio->io_error = error;
3049 return (ZIO_PIPELINE_CONTINUE);
3053 zio_dva_free(zio_t *zio)
3055 metaslab_free(zio->io_spa, zio->io_bp, zio->io_txg, B_FALSE);
3057 return (ZIO_PIPELINE_CONTINUE);
3061 zio_dva_claim(zio_t *zio)
3065 error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg);
3067 zio->io_error = error;
3069 return (ZIO_PIPELINE_CONTINUE);
3073 * Undo an allocation. This is used by zio_done() when an I/O fails
3074 * and we want to give back the block we just allocated.
3075 * This handles both normal blocks and gang blocks.
3078 zio_dva_unallocate(zio_t *zio, zio_gang_node_t *gn, blkptr_t *bp)
3082 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp));
3083 ASSERT(zio->io_bp_override == NULL);
3085 if (!BP_IS_HOLE(bp))
3086 metaslab_free(zio->io_spa, bp, bp->blk_birth, B_TRUE);
3089 for (g = 0; g < SPA_GBH_NBLKPTRS; g++) {
3090 zio_dva_unallocate(zio, gn->gn_child[g],
3091 &gn->gn_gbh->zg_blkptr[g]);
3097 * Try to allocate an intent log block. Return 0 on success, errno on failure.
3100 zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp, uint64_t size,
3104 zio_alloc_list_t io_alloc_list;
3106 ASSERT(txg > spa_syncing_txg(spa));
3108 metaslab_trace_init(&io_alloc_list);
3111 error = metaslab_alloc(spa, spa_log_class(spa), size,
3112 new_bp, 1, txg, NULL, METASLAB_FASTWRITE,
3113 &io_alloc_list, NULL);
3117 error = metaslab_alloc(spa, spa_normal_class(spa), size,
3118 new_bp, 1, txg, NULL, METASLAB_FASTWRITE,
3119 &io_alloc_list, NULL);
3121 metaslab_trace_fini(&io_alloc_list);
3124 BP_SET_LSIZE(new_bp, size);
3125 BP_SET_PSIZE(new_bp, size);
3126 BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF);
3127 BP_SET_CHECKSUM(new_bp,
3128 spa_version(spa) >= SPA_VERSION_SLIM_ZIL
3129 ? ZIO_CHECKSUM_ZILOG2 : ZIO_CHECKSUM_ZILOG);
3130 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG);
3131 BP_SET_LEVEL(new_bp, 0);
3132 BP_SET_DEDUP(new_bp, 0);
3133 BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER);
3140 * Free an intent log block.
3143 zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp)
3145 ASSERT(BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG);
3146 ASSERT(!BP_IS_GANG(bp));
3148 zio_free(spa, txg, bp);
3152 * ==========================================================================
3153 * Read and write to physical devices
3154 * ==========================================================================
3159 * Issue an I/O to the underlying vdev. Typically the issue pipeline
3160 * stops after this stage and will resume upon I/O completion.
3161 * However, there are instances where the vdev layer may need to
3162 * continue the pipeline when an I/O was not issued. Since the I/O
3163 * that was sent to the vdev layer might be different than the one
3164 * currently active in the pipeline (see vdev_queue_io()), we explicitly
3165 * force the underlying vdev layers to call either zio_execute() or
3166 * zio_interrupt() to ensure that the pipeline continues with the correct I/O.
3169 zio_vdev_io_start(zio_t *zio)
3171 vdev_t *vd = zio->io_vd;
3173 spa_t *spa = zio->io_spa;
3177 ASSERT(zio->io_error == 0);
3178 ASSERT(zio->io_child_error[ZIO_CHILD_VDEV] == 0);
3181 if (!(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
3182 spa_config_enter(spa, SCL_ZIO, zio, RW_READER);
3185 * The mirror_ops handle multiple DVAs in a single BP.
3187 vdev_mirror_ops.vdev_op_io_start(zio);
3188 return (ZIO_PIPELINE_STOP);
3191 ASSERT3P(zio->io_logical, !=, zio);
3194 * We keep track of time-sensitive I/Os so that the scan thread
3195 * can quickly react to certain workloads. In particular, we care
3196 * about non-scrubbing, top-level reads and writes with the following
3198 * - synchronous writes of user data to non-slog devices
3199 * - any reads of user data
3200 * When these conditions are met, adjust the timestamp of spa_last_io
3201 * which allows the scan thread to adjust its workload accordingly.
3203 if (!(zio->io_flags & ZIO_FLAG_SCAN_THREAD) && zio->io_bp != NULL &&
3204 vd == vd->vdev_top && !vd->vdev_islog &&
3205 zio->io_bookmark.zb_objset != DMU_META_OBJSET &&
3206 zio->io_txg != spa_syncing_txg(spa)) {
3207 uint64_t old = spa->spa_last_io;
3208 uint64_t new = ddi_get_lbolt64();
3210 (void) atomic_cas_64(&spa->spa_last_io, old, new);
3213 align = 1ULL << vd->vdev_top->vdev_ashift;
3215 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL) &&
3216 P2PHASE(zio->io_size, align) != 0) {
3217 /* Transform logical writes to be a full physical block size. */
3218 uint64_t asize = P2ROUNDUP(zio->io_size, align);
3219 abd_t *abuf = abd_alloc_sametype(zio->io_abd, asize);
3220 ASSERT(vd == vd->vdev_top);
3221 if (zio->io_type == ZIO_TYPE_WRITE) {
3222 abd_copy(abuf, zio->io_abd, zio->io_size);
3223 abd_zero_off(abuf, zio->io_size, asize - zio->io_size);
3225 zio_push_transform(zio, abuf, asize, asize, zio_subblock);
3229 * If this is not a physical io, make sure that it is properly aligned
3230 * before proceeding.
3232 if (!(zio->io_flags & ZIO_FLAG_PHYSICAL)) {
3233 ASSERT0(P2PHASE(zio->io_offset, align));
3234 ASSERT0(P2PHASE(zio->io_size, align));
3237 * For physical writes, we allow 512b aligned writes and assume
3238 * the device will perform a read-modify-write as necessary.
3240 ASSERT0(P2PHASE(zio->io_offset, SPA_MINBLOCKSIZE));
3241 ASSERT0(P2PHASE(zio->io_size, SPA_MINBLOCKSIZE));
3244 VERIFY(zio->io_type != ZIO_TYPE_WRITE || spa_writeable(spa));
3247 * If this is a repair I/O, and there's no self-healing involved --
3248 * that is, we're just resilvering what we expect to resilver --
3249 * then don't do the I/O unless zio's txg is actually in vd's DTL.
3250 * This prevents spurious resilvering with nested replication.
3251 * For example, given a mirror of mirrors, (A+B)+(C+D), if only
3252 * A is out of date, we'll read from C+D, then use the data to
3253 * resilver A+B -- but we don't actually want to resilver B, just A.
3254 * The top-level mirror has no way to know this, so instead we just
3255 * discard unnecessary repairs as we work our way down the vdev tree.
3256 * The same logic applies to any form of nested replication:
3257 * ditto + mirror, RAID-Z + replacing, etc. This covers them all.
3259 if ((zio->io_flags & ZIO_FLAG_IO_REPAIR) &&
3260 !(zio->io_flags & ZIO_FLAG_SELF_HEAL) &&
3261 zio->io_txg != 0 && /* not a delegated i/o */
3262 !vdev_dtl_contains(vd, DTL_PARTIAL, zio->io_txg, 1)) {
3263 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
3264 zio_vdev_io_bypass(zio);
3265 return (ZIO_PIPELINE_CONTINUE);
3268 if (vd->vdev_ops->vdev_op_leaf &&
3269 (zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE)) {
3271 if (zio->io_type == ZIO_TYPE_READ && vdev_cache_read(zio))
3272 return (ZIO_PIPELINE_CONTINUE);
3274 if ((zio = vdev_queue_io(zio)) == NULL)
3275 return (ZIO_PIPELINE_STOP);
3277 if (!vdev_accessible(vd, zio)) {
3278 zio->io_error = SET_ERROR(ENXIO);
3280 return (ZIO_PIPELINE_STOP);
3284 zio->io_delay = gethrtime();
3285 vd->vdev_ops->vdev_op_io_start(zio);
3286 return (ZIO_PIPELINE_STOP);
3290 zio_vdev_io_done(zio_t *zio)
3292 vdev_t *vd = zio->io_vd;
3293 vdev_ops_t *ops = vd ? vd->vdev_ops : &vdev_mirror_ops;
3294 boolean_t unexpected_error = B_FALSE;
3296 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
3297 return (ZIO_PIPELINE_STOP);
3299 ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE);
3302 zio->io_delay = gethrtime() - zio->io_delay;
3304 if (vd != NULL && vd->vdev_ops->vdev_op_leaf) {
3306 vdev_queue_io_done(zio);
3308 if (zio->io_type == ZIO_TYPE_WRITE)
3309 vdev_cache_write(zio);
3311 if (zio_injection_enabled && zio->io_error == 0)
3312 zio->io_error = zio_handle_device_injection(vd,
3315 if (zio_injection_enabled && zio->io_error == 0)
3316 zio->io_error = zio_handle_label_injection(zio, EIO);
3318 if (zio->io_error) {
3319 if (!vdev_accessible(vd, zio)) {
3320 zio->io_error = SET_ERROR(ENXIO);
3322 unexpected_error = B_TRUE;
3327 ops->vdev_op_io_done(zio);
3329 if (unexpected_error)
3330 VERIFY(vdev_probe(vd, zio) == NULL);
3332 return (ZIO_PIPELINE_CONTINUE);
3336 * For non-raidz ZIOs, we can just copy aside the bad data read from the
3337 * disk, and use that to finish the checksum ereport later.
3340 zio_vsd_default_cksum_finish(zio_cksum_report_t *zcr,
3341 const abd_t *good_buf)
3343 /* no processing needed */
3344 zfs_ereport_finish_checksum(zcr, good_buf, zcr->zcr_cbdata, B_FALSE);
3349 zio_vsd_default_cksum_report(zio_t *zio, zio_cksum_report_t *zcr, void *ignored)
3351 void *abd = abd_alloc_sametype(zio->io_abd, zio->io_size);
3353 abd_copy(abd, zio->io_abd, zio->io_size);
3355 zcr->zcr_cbinfo = zio->io_size;
3356 zcr->zcr_cbdata = abd;
3357 zcr->zcr_finish = zio_vsd_default_cksum_finish;
3358 zcr->zcr_free = zio_abd_free;
3362 zio_vdev_io_assess(zio_t *zio)
3364 vdev_t *vd = zio->io_vd;
3366 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
3367 return (ZIO_PIPELINE_STOP);
3369 if (vd == NULL && !(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
3370 spa_config_exit(zio->io_spa, SCL_ZIO, zio);
3372 if (zio->io_vsd != NULL) {
3373 zio->io_vsd_ops->vsd_free(zio);
3377 if (zio_injection_enabled && zio->io_error == 0)
3378 zio->io_error = zio_handle_fault_injection(zio, EIO);
3381 * If the I/O failed, determine whether we should attempt to retry it.
3383 * On retry, we cut in line in the issue queue, since we don't want
3384 * compression/checksumming/etc. work to prevent our (cheap) IO reissue.
3386 if (zio->io_error && vd == NULL &&
3387 !(zio->io_flags & (ZIO_FLAG_DONT_RETRY | ZIO_FLAG_IO_RETRY))) {
3388 ASSERT(!(zio->io_flags & ZIO_FLAG_DONT_QUEUE)); /* not a leaf */
3389 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_BYPASS)); /* not a leaf */
3391 zio->io_flags |= ZIO_FLAG_IO_RETRY |
3392 ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_AGGREGATE;
3393 zio->io_stage = ZIO_STAGE_VDEV_IO_START >> 1;
3394 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE,
3395 zio_requeue_io_start_cut_in_line);
3396 return (ZIO_PIPELINE_STOP);
3400 * If we got an error on a leaf device, convert it to ENXIO
3401 * if the device is not accessible at all.
3403 if (zio->io_error && vd != NULL && vd->vdev_ops->vdev_op_leaf &&
3404 !vdev_accessible(vd, zio))
3405 zio->io_error = SET_ERROR(ENXIO);
3408 * If we can't write to an interior vdev (mirror or RAID-Z),
3409 * set vdev_cant_write so that we stop trying to allocate from it.
3411 if (zio->io_error == ENXIO && zio->io_type == ZIO_TYPE_WRITE &&
3412 vd != NULL && !vd->vdev_ops->vdev_op_leaf) {
3413 vd->vdev_cant_write = B_TRUE;
3417 * If a cache flush returns ENOTSUP or ENOTTY, we know that no future
3418 * attempts will ever succeed. In this case we set a persistent bit so
3419 * that we don't bother with it in the future.
3421 if ((zio->io_error == ENOTSUP || zio->io_error == ENOTTY) &&
3422 zio->io_type == ZIO_TYPE_IOCTL &&
3423 zio->io_cmd == DKIOCFLUSHWRITECACHE && vd != NULL)
3424 vd->vdev_nowritecache = B_TRUE;
3427 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
3429 if (vd != NULL && vd->vdev_ops->vdev_op_leaf &&
3430 zio->io_physdone != NULL) {
3431 ASSERT(!(zio->io_flags & ZIO_FLAG_DELEGATED));
3432 ASSERT(zio->io_child_type == ZIO_CHILD_VDEV);
3433 zio->io_physdone(zio->io_logical);
3436 return (ZIO_PIPELINE_CONTINUE);
3440 zio_vdev_io_reissue(zio_t *zio)
3442 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START);
3443 ASSERT(zio->io_error == 0);
3445 zio->io_stage >>= 1;
3449 zio_vdev_io_redone(zio_t *zio)
3451 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_DONE);
3453 zio->io_stage >>= 1;
3457 zio_vdev_io_bypass(zio_t *zio)
3459 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START);
3460 ASSERT(zio->io_error == 0);
3462 zio->io_flags |= ZIO_FLAG_IO_BYPASS;
3463 zio->io_stage = ZIO_STAGE_VDEV_IO_ASSESS >> 1;
3467 * ==========================================================================
3468 * Generate and verify checksums
3469 * ==========================================================================
3472 zio_checksum_generate(zio_t *zio)
3474 blkptr_t *bp = zio->io_bp;
3475 enum zio_checksum checksum;
3479 * This is zio_write_phys().
3480 * We're either generating a label checksum, or none at all.
3482 checksum = zio->io_prop.zp_checksum;
3484 if (checksum == ZIO_CHECKSUM_OFF)
3485 return (ZIO_PIPELINE_CONTINUE);
3487 ASSERT(checksum == ZIO_CHECKSUM_LABEL);
3489 if (BP_IS_GANG(bp) && zio->io_child_type == ZIO_CHILD_GANG) {
3490 ASSERT(!IO_IS_ALLOCATING(zio));
3491 checksum = ZIO_CHECKSUM_GANG_HEADER;
3493 checksum = BP_GET_CHECKSUM(bp);
3497 zio_checksum_compute(zio, checksum, zio->io_abd, zio->io_size);
3499 return (ZIO_PIPELINE_CONTINUE);
3503 zio_checksum_verify(zio_t *zio)
3505 zio_bad_cksum_t info;
3506 blkptr_t *bp = zio->io_bp;
3509 ASSERT(zio->io_vd != NULL);
3513 * This is zio_read_phys().
3514 * We're either verifying a label checksum, or nothing at all.
3516 if (zio->io_prop.zp_checksum == ZIO_CHECKSUM_OFF)
3517 return (ZIO_PIPELINE_CONTINUE);
3519 ASSERT(zio->io_prop.zp_checksum == ZIO_CHECKSUM_LABEL);
3522 if ((error = zio_checksum_error(zio, &info)) != 0) {
3523 zio->io_error = error;
3524 if (error == ECKSUM &&
3525 !(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
3526 zfs_ereport_start_checksum(zio->io_spa,
3527 zio->io_vd, zio, zio->io_offset,
3528 zio->io_size, NULL, &info);
3532 return (ZIO_PIPELINE_CONTINUE);
3536 * Called by RAID-Z to ensure we don't compute the checksum twice.
3539 zio_checksum_verified(zio_t *zio)
3541 zio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY;
3545 * ==========================================================================
3546 * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other.
3547 * An error of 0 indicates success. ENXIO indicates whole-device failure,
3548 * which may be transient (e.g. unplugged) or permament. ECKSUM and EIO
3549 * indicate errors that are specific to one I/O, and most likely permanent.
3550 * Any other error is presumed to be worse because we weren't expecting it.
3551 * ==========================================================================
3554 zio_worst_error(int e1, int e2)
3556 static int zio_error_rank[] = { 0, ENXIO, ECKSUM, EIO };
3559 for (r1 = 0; r1 < sizeof (zio_error_rank) / sizeof (int); r1++)
3560 if (e1 == zio_error_rank[r1])
3563 for (r2 = 0; r2 < sizeof (zio_error_rank) / sizeof (int); r2++)
3564 if (e2 == zio_error_rank[r2])
3567 return (r1 > r2 ? e1 : e2);
3571 * ==========================================================================
3573 * ==========================================================================
3576 zio_ready(zio_t *zio)
3578 blkptr_t *bp = zio->io_bp;
3579 zio_t *pio, *pio_next;
3580 zio_link_t *zl = NULL;
3582 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) ||
3583 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_READY))
3584 return (ZIO_PIPELINE_STOP);
3586 if (zio->io_ready) {
3587 ASSERT(IO_IS_ALLOCATING(zio));
3588 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp) ||
3589 (zio->io_flags & ZIO_FLAG_NOPWRITE));
3590 ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0);
3595 if (bp != NULL && bp != &zio->io_bp_copy)
3596 zio->io_bp_copy = *bp;
3598 if (zio->io_error != 0) {
3599 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
3601 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING) {
3602 ASSERT(IO_IS_ALLOCATING(zio));
3603 ASSERT(zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE);
3605 * We were unable to allocate anything, unreserve and
3606 * issue the next I/O to allocate.
3608 metaslab_class_throttle_unreserve(
3609 spa_normal_class(zio->io_spa),
3610 zio->io_prop.zp_copies, zio);
3611 zio_allocate_dispatch(zio->io_spa);
3615 mutex_enter(&zio->io_lock);
3616 zio->io_state[ZIO_WAIT_READY] = 1;
3617 pio = zio_walk_parents(zio, &zl);
3618 mutex_exit(&zio->io_lock);
3621 * As we notify zio's parents, new parents could be added.
3622 * New parents go to the head of zio's io_parent_list, however,
3623 * so we will (correctly) not notify them. The remainder of zio's
3624 * io_parent_list, from 'pio_next' onward, cannot change because
3625 * all parents must wait for us to be done before they can be done.
3627 for (; pio != NULL; pio = pio_next) {
3628 pio_next = zio_walk_parents(zio, &zl);
3629 zio_notify_parent(pio, zio, ZIO_WAIT_READY);
3632 if (zio->io_flags & ZIO_FLAG_NODATA) {
3633 if (BP_IS_GANG(bp)) {
3634 zio->io_flags &= ~ZIO_FLAG_NODATA;
3636 ASSERT((uintptr_t)zio->io_abd < SPA_MAXBLOCKSIZE);
3637 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES;
3641 if (zio_injection_enabled &&
3642 zio->io_spa->spa_syncing_txg == zio->io_txg)
3643 zio_handle_ignored_writes(zio);
3645 return (ZIO_PIPELINE_CONTINUE);
3649 * Update the allocation throttle accounting.
3652 zio_dva_throttle_done(zio_t *zio)
3654 zio_t *pio = zio_unique_parent(zio);
3655 vdev_t *vd = zio->io_vd;
3656 int flags = METASLAB_ASYNC_ALLOC;
3657 ASSERTV(zio_t *lio = zio->io_logical);
3659 ASSERT3P(zio->io_bp, !=, NULL);
3660 ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE);
3661 ASSERT3U(zio->io_priority, ==, ZIO_PRIORITY_ASYNC_WRITE);
3662 ASSERT3U(zio->io_child_type, ==, ZIO_CHILD_VDEV);
3664 ASSERT3P(vd, ==, vd->vdev_top);
3665 ASSERT(!(zio->io_flags & (ZIO_FLAG_IO_REPAIR | ZIO_FLAG_IO_RETRY)));
3666 ASSERT(zio->io_flags & ZIO_FLAG_IO_ALLOCATING);
3667 ASSERT(!(lio->io_flags & ZIO_FLAG_IO_REWRITE));
3668 ASSERT(!(lio->io_orig_flags & ZIO_FLAG_NODATA));
3671 * Parents of gang children can have two flavors -- ones that
3672 * allocated the gang header (will have ZIO_FLAG_IO_REWRITE set)
3673 * and ones that allocated the constituent blocks. The allocation
3674 * throttle needs to know the allocating parent zio so we must find
3677 if (pio->io_child_type == ZIO_CHILD_GANG) {
3679 * If our parent is a rewrite gang child then our grandparent
3680 * would have been the one that performed the allocation.
3682 if (pio->io_flags & ZIO_FLAG_IO_REWRITE)
3683 pio = zio_unique_parent(pio);
3684 flags |= METASLAB_GANG_CHILD;
3687 ASSERT(IO_IS_ALLOCATING(pio));
3688 ASSERT3P(zio, !=, zio->io_logical);
3689 ASSERT(zio->io_logical != NULL);
3690 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REPAIR));
3691 ASSERT0(zio->io_flags & ZIO_FLAG_NOPWRITE);
3693 mutex_enter(&pio->io_lock);
3694 metaslab_group_alloc_decrement(zio->io_spa, vd->vdev_id, pio, flags);
3695 mutex_exit(&pio->io_lock);
3697 metaslab_class_throttle_unreserve(spa_normal_class(zio->io_spa),
3701 * Call into the pipeline to see if there is more work that
3702 * needs to be done. If there is work to be done it will be
3703 * dispatched to another taskq thread.
3705 zio_allocate_dispatch(zio->io_spa);
3709 zio_done(zio_t *zio)
3712 * Always attempt to keep stack usage minimal here since
3713 * we can be called recurisvely up to 19 levels deep.
3715 const uint64_t psize = zio->io_size;
3716 zio_t *pio, *pio_next;
3718 zio_link_t *zl = NULL;
3721 * If our children haven't all completed,
3722 * wait for them and then repeat this pipeline stage.
3724 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE) ||
3725 zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE) ||
3726 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE) ||
3727 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_DONE))
3728 return (ZIO_PIPELINE_STOP);
3731 * If the allocation throttle is enabled, then update the accounting.
3732 * We only track child I/Os that are part of an allocating async
3733 * write. We must do this since the allocation is performed
3734 * by the logical I/O but the actual write is done by child I/Os.
3736 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING &&
3737 zio->io_child_type == ZIO_CHILD_VDEV) {
3738 ASSERT(spa_normal_class(
3739 zio->io_spa)->mc_alloc_throttle_enabled);
3740 zio_dva_throttle_done(zio);
3744 * If the allocation throttle is enabled, verify that
3745 * we have decremented the refcounts for every I/O that was throttled.
3747 if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING) {
3748 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
3749 ASSERT(zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE);
3750 ASSERT(zio->io_bp != NULL);
3751 metaslab_group_alloc_verify(zio->io_spa, zio->io_bp, zio);
3752 VERIFY(refcount_not_held(
3753 &(spa_normal_class(zio->io_spa)->mc_alloc_slots), zio));
3757 for (c = 0; c < ZIO_CHILD_TYPES; c++)
3758 for (w = 0; w < ZIO_WAIT_TYPES; w++)
3759 ASSERT(zio->io_children[c][w] == 0);
3761 if (zio->io_bp != NULL && !BP_IS_EMBEDDED(zio->io_bp)) {
3762 ASSERT(zio->io_bp->blk_pad[0] == 0);
3763 ASSERT(zio->io_bp->blk_pad[1] == 0);
3764 ASSERT(bcmp(zio->io_bp, &zio->io_bp_copy,
3765 sizeof (blkptr_t)) == 0 ||
3766 (zio->io_bp == zio_unique_parent(zio)->io_bp));
3767 if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(zio->io_bp) &&
3768 zio->io_bp_override == NULL &&
3769 !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) {
3770 ASSERT(!BP_SHOULD_BYTESWAP(zio->io_bp));
3771 ASSERT3U(zio->io_prop.zp_copies, <=,
3772 BP_GET_NDVAS(zio->io_bp));
3773 ASSERT(BP_COUNT_GANG(zio->io_bp) == 0 ||
3774 (BP_COUNT_GANG(zio->io_bp) ==
3775 BP_GET_NDVAS(zio->io_bp)));
3777 if (zio->io_flags & ZIO_FLAG_NOPWRITE)
3778 VERIFY(BP_EQUAL(zio->io_bp, &zio->io_bp_orig));
3782 * If there were child vdev/gang/ddt errors, they apply to us now.
3784 zio_inherit_child_errors(zio, ZIO_CHILD_VDEV);
3785 zio_inherit_child_errors(zio, ZIO_CHILD_GANG);
3786 zio_inherit_child_errors(zio, ZIO_CHILD_DDT);
3789 * If the I/O on the transformed data was successful, generate any
3790 * checksum reports now while we still have the transformed data.
3792 if (zio->io_error == 0) {
3793 while (zio->io_cksum_report != NULL) {
3794 zio_cksum_report_t *zcr = zio->io_cksum_report;
3795 uint64_t align = zcr->zcr_align;
3796 uint64_t asize = P2ROUNDUP(psize, align);
3797 abd_t *adata = zio->io_abd;
3799 if (asize != psize) {
3800 adata = abd_alloc(asize, B_TRUE);
3801 abd_copy(adata, zio->io_abd, psize);
3802 abd_zero_off(adata, psize, asize - psize);
3805 zio->io_cksum_report = zcr->zcr_next;
3806 zcr->zcr_next = NULL;
3807 zcr->zcr_finish(zcr, adata);
3808 zfs_ereport_free_checksum(zcr);
3815 zio_pop_transforms(zio); /* note: may set zio->io_error */
3817 vdev_stat_update(zio, psize);
3820 * If this I/O is attached to a particular vdev is slow, exceeding
3821 * 30 seconds to complete, post an error described the I/O delay.
3822 * We ignore these errors if the device is currently unavailable.
3824 if (zio->io_delay >= MSEC2NSEC(zio_delay_max)) {
3825 if (zio->io_vd != NULL && !vdev_is_dead(zio->io_vd))
3826 zfs_ereport_post(FM_EREPORT_ZFS_DELAY, zio->io_spa,
3827 zio->io_vd, zio, 0, 0);
3830 if (zio->io_error) {
3832 * If this I/O is attached to a particular vdev,
3833 * generate an error message describing the I/O failure
3834 * at the block level. We ignore these errors if the
3835 * device is currently unavailable.
3837 if (zio->io_error != ECKSUM && zio->io_vd != NULL &&
3838 !vdev_is_dead(zio->io_vd))
3839 zfs_ereport_post(FM_EREPORT_ZFS_IO, zio->io_spa,
3840 zio->io_vd, zio, 0, 0);
3842 if ((zio->io_error == EIO || !(zio->io_flags &
3843 (ZIO_FLAG_SPECULATIVE | ZIO_FLAG_DONT_PROPAGATE))) &&
3844 zio == zio->io_logical) {
3846 * For logical I/O requests, tell the SPA to log the
3847 * error and generate a logical data ereport.
3849 spa_log_error(zio->io_spa, zio);
3850 zfs_ereport_post(FM_EREPORT_ZFS_DATA, zio->io_spa,
3855 if (zio->io_error && zio == zio->io_logical) {
3857 * Determine whether zio should be reexecuted. This will
3858 * propagate all the way to the root via zio_notify_parent().
3860 ASSERT(zio->io_vd == NULL && zio->io_bp != NULL);
3861 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
3863 if (IO_IS_ALLOCATING(zio) &&
3864 !(zio->io_flags & ZIO_FLAG_CANFAIL)) {
3865 if (zio->io_error != ENOSPC)
3866 zio->io_reexecute |= ZIO_REEXECUTE_NOW;
3868 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
3871 if ((zio->io_type == ZIO_TYPE_READ ||
3872 zio->io_type == ZIO_TYPE_FREE) &&
3873 !(zio->io_flags & ZIO_FLAG_SCAN_THREAD) &&
3874 zio->io_error == ENXIO &&
3875 spa_load_state(zio->io_spa) == SPA_LOAD_NONE &&
3876 spa_get_failmode(zio->io_spa) != ZIO_FAILURE_MODE_CONTINUE)
3877 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
3879 if (!(zio->io_flags & ZIO_FLAG_CANFAIL) && !zio->io_reexecute)
3880 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
3883 * Here is a possibly good place to attempt to do
3884 * either combinatorial reconstruction or error correction
3885 * based on checksums. It also might be a good place
3886 * to send out preliminary ereports before we suspend
3892 * If there were logical child errors, they apply to us now.
3893 * We defer this until now to avoid conflating logical child
3894 * errors with errors that happened to the zio itself when
3895 * updating vdev stats and reporting FMA events above.
3897 zio_inherit_child_errors(zio, ZIO_CHILD_LOGICAL);
3899 if ((zio->io_error || zio->io_reexecute) &&
3900 IO_IS_ALLOCATING(zio) && zio->io_gang_leader == zio &&
3901 !(zio->io_flags & (ZIO_FLAG_IO_REWRITE | ZIO_FLAG_NOPWRITE)))
3902 zio_dva_unallocate(zio, zio->io_gang_tree, zio->io_bp);
3904 zio_gang_tree_free(&zio->io_gang_tree);
3907 * Godfather I/Os should never suspend.
3909 if ((zio->io_flags & ZIO_FLAG_GODFATHER) &&
3910 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND))
3911 zio->io_reexecute &= ~ZIO_REEXECUTE_SUSPEND;
3913 if (zio->io_reexecute) {
3915 * This is a logical I/O that wants to reexecute.
3917 * Reexecute is top-down. When an i/o fails, if it's not
3918 * the root, it simply notifies its parent and sticks around.
3919 * The parent, seeing that it still has children in zio_done(),
3920 * does the same. This percolates all the way up to the root.
3921 * The root i/o will reexecute or suspend the entire tree.
3923 * This approach ensures that zio_reexecute() honors
3924 * all the original i/o dependency relationships, e.g.
3925 * parents not executing until children are ready.
3927 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
3929 zio->io_gang_leader = NULL;
3931 mutex_enter(&zio->io_lock);
3932 zio->io_state[ZIO_WAIT_DONE] = 1;
3933 mutex_exit(&zio->io_lock);
3936 * "The Godfather" I/O monitors its children but is
3937 * not a true parent to them. It will track them through
3938 * the pipeline but severs its ties whenever they get into
3939 * trouble (e.g. suspended). This allows "The Godfather"
3940 * I/O to return status without blocking.
3943 for (pio = zio_walk_parents(zio, &zl); pio != NULL;
3945 zio_link_t *remove_zl = zl;
3946 pio_next = zio_walk_parents(zio, &zl);
3948 if ((pio->io_flags & ZIO_FLAG_GODFATHER) &&
3949 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) {
3950 zio_remove_child(pio, zio, remove_zl);
3951 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3955 if ((pio = zio_unique_parent(zio)) != NULL) {
3957 * We're not a root i/o, so there's nothing to do
3958 * but notify our parent. Don't propagate errors
3959 * upward since we haven't permanently failed yet.
3961 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER));
3962 zio->io_flags |= ZIO_FLAG_DONT_PROPAGATE;
3963 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3964 } else if (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND) {
3966 * We'd fail again if we reexecuted now, so suspend
3967 * until conditions improve (e.g. device comes online).
3969 zio_suspend(zio->io_spa, zio);
3972 * Reexecution is potentially a huge amount of work.
3973 * Hand it off to the otherwise-unused claim taskq.
3975 ASSERT(taskq_empty_ent(&zio->io_tqent));
3976 spa_taskq_dispatch_ent(zio->io_spa,
3977 ZIO_TYPE_CLAIM, ZIO_TASKQ_ISSUE,
3978 (task_func_t *)zio_reexecute, zio, 0,
3981 return (ZIO_PIPELINE_STOP);
3984 ASSERT(zio->io_child_count == 0);
3985 ASSERT(zio->io_reexecute == 0);
3986 ASSERT(zio->io_error == 0 || (zio->io_flags & ZIO_FLAG_CANFAIL));
3989 * Report any checksum errors, since the I/O is complete.
3991 while (zio->io_cksum_report != NULL) {
3992 zio_cksum_report_t *zcr = zio->io_cksum_report;
3993 zio->io_cksum_report = zcr->zcr_next;
3994 zcr->zcr_next = NULL;
3995 zcr->zcr_finish(zcr, NULL);
3996 zfs_ereport_free_checksum(zcr);
3999 if (zio->io_flags & ZIO_FLAG_FASTWRITE && zio->io_bp &&
4000 !BP_IS_HOLE(zio->io_bp) && !BP_IS_EMBEDDED(zio->io_bp) &&
4001 !(zio->io_flags & ZIO_FLAG_NOPWRITE)) {
4002 metaslab_fastwrite_unmark(zio->io_spa, zio->io_bp);
4006 * It is the responsibility of the done callback to ensure that this
4007 * particular zio is no longer discoverable for adoption, and as
4008 * such, cannot acquire any new parents.
4013 mutex_enter(&zio->io_lock);
4014 zio->io_state[ZIO_WAIT_DONE] = 1;
4015 mutex_exit(&zio->io_lock);
4018 for (pio = zio_walk_parents(zio, &zl); pio != NULL; pio = pio_next) {
4019 zio_link_t *remove_zl = zl;
4020 pio_next = zio_walk_parents(zio, &zl);
4021 zio_remove_child(pio, zio, remove_zl);
4022 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
4025 if (zio->io_waiter != NULL) {
4026 mutex_enter(&zio->io_lock);
4027 zio->io_executor = NULL;
4028 cv_broadcast(&zio->io_cv);
4029 mutex_exit(&zio->io_lock);
4034 return (ZIO_PIPELINE_STOP);
4038 * ==========================================================================
4039 * I/O pipeline definition
4040 * ==========================================================================
4042 static zio_pipe_stage_t *zio_pipeline[] = {
4049 zio_checksum_generate,
4065 zio_checksum_verify,
4073 * Compare two zbookmark_phys_t's to see which we would reach first in a
4074 * pre-order traversal of the object tree.
4076 * This is simple in every case aside from the meta-dnode object. For all other
4077 * objects, we traverse them in order (object 1 before object 2, and so on).
4078 * However, all of these objects are traversed while traversing object 0, since
4079 * the data it points to is the list of objects. Thus, we need to convert to a
4080 * canonical representation so we can compare meta-dnode bookmarks to
4081 * non-meta-dnode bookmarks.
4083 * We do this by calculating "equivalents" for each field of the zbookmark.
4084 * zbookmarks outside of the meta-dnode use their own object and level, and
4085 * calculate the level 0 equivalent (the first L0 blkid that is contained in the
4086 * blocks this bookmark refers to) by multiplying their blkid by their span
4087 * (the number of L0 blocks contained within one block at their level).
4088 * zbookmarks inside the meta-dnode calculate their object equivalent
4089 * (which is L0equiv * dnodes per data block), use 0 for their L0equiv, and use
4090 * level + 1<<31 (any value larger than a level could ever be) for their level.
4091 * This causes them to always compare before a bookmark in their object
4092 * equivalent, compare appropriately to bookmarks in other objects, and to
4093 * compare appropriately to other bookmarks in the meta-dnode.
4096 zbookmark_compare(uint16_t dbss1, uint8_t ibs1, uint16_t dbss2, uint8_t ibs2,
4097 const zbookmark_phys_t *zb1, const zbookmark_phys_t *zb2)
4100 * These variables represent the "equivalent" values for the zbookmark,
4101 * after converting zbookmarks inside the meta dnode to their
4102 * normal-object equivalents.
4104 uint64_t zb1obj, zb2obj;
4105 uint64_t zb1L0, zb2L0;
4106 uint64_t zb1level, zb2level;
4108 if (zb1->zb_object == zb2->zb_object &&
4109 zb1->zb_level == zb2->zb_level &&
4110 zb1->zb_blkid == zb2->zb_blkid)
4114 * BP_SPANB calculates the span in blocks.
4116 zb1L0 = (zb1->zb_blkid) * BP_SPANB(ibs1, zb1->zb_level);
4117 zb2L0 = (zb2->zb_blkid) * BP_SPANB(ibs2, zb2->zb_level);
4119 if (zb1->zb_object == DMU_META_DNODE_OBJECT) {
4120 zb1obj = zb1L0 * (dbss1 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT));
4122 zb1level = zb1->zb_level + COMPARE_META_LEVEL;
4124 zb1obj = zb1->zb_object;
4125 zb1level = zb1->zb_level;
4128 if (zb2->zb_object == DMU_META_DNODE_OBJECT) {
4129 zb2obj = zb2L0 * (dbss2 << (SPA_MINBLOCKSHIFT - DNODE_SHIFT));
4131 zb2level = zb2->zb_level + COMPARE_META_LEVEL;
4133 zb2obj = zb2->zb_object;
4134 zb2level = zb2->zb_level;
4137 /* Now that we have a canonical representation, do the comparison. */
4138 if (zb1obj != zb2obj)
4139 return (zb1obj < zb2obj ? -1 : 1);
4140 else if (zb1L0 != zb2L0)
4141 return (zb1L0 < zb2L0 ? -1 : 1);
4142 else if (zb1level != zb2level)
4143 return (zb1level > zb2level ? -1 : 1);
4145 * This can (theoretically) happen if the bookmarks have the same object
4146 * and level, but different blkids, if the block sizes are not the same.
4147 * There is presently no way to change the indirect block sizes
4153 * This function checks the following: given that last_block is the place that
4154 * our traversal stopped last time, does that guarantee that we've visited
4155 * every node under subtree_root? Therefore, we can't just use the raw output
4156 * of zbookmark_compare. We have to pass in a modified version of
4157 * subtree_root; by incrementing the block id, and then checking whether
4158 * last_block is before or equal to that, we can tell whether or not having
4159 * visited last_block implies that all of subtree_root's children have been
4163 zbookmark_subtree_completed(const dnode_phys_t *dnp,
4164 const zbookmark_phys_t *subtree_root, const zbookmark_phys_t *last_block)
4166 zbookmark_phys_t mod_zb = *subtree_root;
4168 ASSERT(last_block->zb_level == 0);
4170 /* The objset_phys_t isn't before anything. */
4175 * We pass in 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT) for the
4176 * data block size in sectors, because that variable is only used if
4177 * the bookmark refers to a block in the meta-dnode. Since we don't
4178 * know without examining it what object it refers to, and there's no
4179 * harm in passing in this value in other cases, we always pass it in.
4181 * We pass in 0 for the indirect block size shift because zb2 must be
4182 * level 0. The indirect block size is only used to calculate the span
4183 * of the bookmark, but since the bookmark must be level 0, the span is
4184 * always 1, so the math works out.
4186 * If you make changes to how the zbookmark_compare code works, be sure
4187 * to make sure that this code still works afterwards.
4189 return (zbookmark_compare(dnp->dn_datablkszsec, dnp->dn_indblkshift,
4190 1ULL << (DNODE_BLOCK_SHIFT - SPA_MINBLOCKSHIFT), 0, &mod_zb,
4194 #if defined(_KERNEL) && defined(HAVE_SPL)
4195 EXPORT_SYMBOL(zio_type_name);
4196 EXPORT_SYMBOL(zio_buf_alloc);
4197 EXPORT_SYMBOL(zio_data_buf_alloc);
4198 EXPORT_SYMBOL(zio_buf_free);
4199 EXPORT_SYMBOL(zio_data_buf_free);
4201 module_param(zio_delay_max, int, 0644);
4202 MODULE_PARM_DESC(zio_delay_max, "Max zio millisec delay before posting event");
4204 module_param(zio_requeue_io_start_cut_in_line, int, 0644);
4205 MODULE_PARM_DESC(zio_requeue_io_start_cut_in_line, "Prioritize requeued I/O");
4207 module_param(zfs_sync_pass_deferred_free, int, 0644);
4208 MODULE_PARM_DESC(zfs_sync_pass_deferred_free,
4209 "Defer frees starting in this pass");
4211 module_param(zfs_sync_pass_dont_compress, int, 0644);
4212 MODULE_PARM_DESC(zfs_sync_pass_dont_compress,
4213 "Don't compress starting in this pass");
4215 module_param(zfs_sync_pass_rewrite, int, 0644);
4216 MODULE_PARM_DESC(zfs_sync_pass_rewrite,
4217 "Rewrite new bps starting in this pass");
4219 module_param(zio_dva_throttle_enabled, int, 0644);
4220 MODULE_PARM_DESC(zio_dva_throttle_enabled,
4221 "Throttle block allocations in the ZIO pipeline");