Kernel/VM/ScatterGatherList.cpp


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/*
 * Copyright (c) 2021, the SerenityOS developers.
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <Kernel/VM/ScatterGatherList.h>

namespace Kernel {

RefPtr<ScatterGatherList> ScatterGatherList::try_create(AsyncBlockDeviceRequest& request, Span<NonnullRefPtr<PhysicalPage>> allocated_pages, size_t device_block_size)
{
    auto vm_object = AnonymousVMObject::try_create_with_physical_pages(allocated_pages);
    if (!vm_object)
        return {};
    return adopt_ref_if_nonnull(new (nothrow) ScatterGatherList(vm_object.release_nonnull(), request, device_block_size));
}

ScatterGatherList::ScatterGatherList(NonnullRefPtr<AnonymousVMObject> vm_object, AsyncBlockDeviceRequest& request, size_t device_block_size)
    : m_vm_object(move(vm_object))
{
    m_dma_region = MM.allocate_kernel_region_with_vmobject(m_vm_object, page_round_up((request.block_count() * device_block_size)), "AHCI Scattered DMA", Region::Access::Read | Region::Access::Write, Region::Cacheable::Yes);
}

}