Function zio_done

freebsd/contrib/openzfs/module/zfs/zio.c:4458–4824

}

static zio_t *
zio_done(zio_t *zio)
{
	/*
	 * Always attempt to keep stack usage minimal here since
	 * we can be called recursively up to 19 levels deep.
	 */
	const uint64_t psize = zio->io_size;
	zio_t *pio, *pio_next;
	zio_link_t *zl = NULL;

	/*
	 * If our children haven't all completed,
	 * wait for them and then repeat this pipeline stage.
	 */
	if (zio_wait_for_children(zio, ZIO_CHILD_ALL_BITS, ZIO_WAIT_DONE)) {
		return (NULL);
	}

	/*
	 * If the allocation throttle is enabled, then update the accounting.
	 * We only track child I/Os that are part of an allocating async
	 * write. We must do this since the allocation is performed
	 * by the logical I/O but the actual write is done by child I/Os.
	 */
	if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING &&
	    zio->io_child_type == ZIO_CHILD_VDEV) {
		ASSERT(zio->io_metaslab_class != NULL);
		ASSERT(zio->io_metaslab_class->mc_alloc_throttle_enabled);
		zio_dva_throttle_done(zio);
	}

	/*
	 * If the allocation throttle is enabled, verify that
	 * we have decremented the refcounts for every I/O that was throttled.
	 */
	if (zio->io_flags & ZIO_FLAG_IO_ALLOCATING) {
		ASSERT(zio->io_type == ZIO_TYPE_WRITE);
		ASSERT(zio->io_priority == ZIO_PRIORITY_ASYNC_WRITE);
		ASSERT(zio->io_bp != NULL);

		metaslab_group_alloc_verify(zio->io_spa, zio->io_bp, zio,
		    zio->io_allocator);
		VERIFY(zfs_refcount_not_held(&zio->io_metaslab_class->
		    mc_allocator[zio->io_allocator].mca_alloc_slots, zio));
	}


	for (int c = 0; c < ZIO_CHILD_TYPES; c++)
		for (int w = 0; w < ZIO_WAIT_TYPES; w++)
			ASSERT(zio->io_children[c][w] == 0);

	if (zio->io_bp != NULL && !BP_IS_EMBEDDED(zio->io_bp)) {
		ASSERT(zio->io_bp->blk_pad[0] == 0);
		ASSERT(zio->io_bp->blk_pad[1] == 0);
		ASSERT(bcmp(zio->io_bp, &zio->io_bp_copy,
		    sizeof (blkptr_t)) == 0 ||
		    (zio->io_bp == zio_unique_parent(zio)->io_bp));