ladybird/Kernel/Memory/ScatterGatherList.cpp
sin-ack 4bfd6e41b9 Kernel: Make Kernel::VMObject allocation functions return KResultOr
This makes for nicer handling of errors compared to checking whether a
RefPtr is null. Additionally, this will give way to return different
types of errors in the future.
2021-08-15 15:41:02 +02:00

28 lines
1.1 KiB
C++

/*
* Copyright (c) 2021, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/Memory/ScatterGatherList.h>
namespace Kernel::Memory {
RefPtr<ScatterGatherList> ScatterGatherList::try_create(AsyncBlockDeviceRequest& request, Span<NonnullRefPtr<PhysicalPage>> allocated_pages, size_t device_block_size)
{
auto maybe_vm_object = AnonymousVMObject::try_create_with_physical_pages(allocated_pages);
if (maybe_vm_object.is_error()) {
// FIXME: Would be nice to be able to return a KResultOr here.
return {};
}
return adopt_ref_if_nonnull(new (nothrow) ScatterGatherList(maybe_vm_object.release_value(), 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);
}
}