Kernel/ScatterGatherList: Return ErrorOr from try_create

This removes the TODO from the try_create API to return ErrorOr. This
is also a preparation patch to move the init code in the constructor
that can fail to this try_create function.

2 files changed, 4 insertions, 8 deletions

diff --git a/Kernel/Memory/ScatterGatherList.cpp b/Kernel/Memory/ScatterGatherList.cpp
index 1eb9b6e53b..f49237c2d9 100644
--- a/Kernel/Memory/ScatterGatherList.cpp
+++ b/Kernel/Memory/ScatterGatherList.cpp
@@ -8,14 +8,10 @@
 
 namespace Kernel::Memory {
 
-LockRefPtr<ScatterGatherList> ScatterGatherList::try_create(AsyncBlockDeviceRequest& request, Span<NonnullRefPtr<PhysicalPage>> allocated_pages, size_t device_block_size)
+ErrorOr<LockRefPtr<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 ErrorOr here.
-        return {};
-    }
-    return adopt_lock_ref_if_nonnull(new (nothrow) ScatterGatherList(maybe_vm_object.release_value(), request, device_block_size));
+    auto vm_object = TRY(AnonymousVMObject::try_create_with_physical_pages(allocated_pages));
+    return adopt_lock_ref_if_nonnull(new (nothrow) ScatterGatherList(vm_object, request, device_block_size));
 }
 
 ScatterGatherList::ScatterGatherList(NonnullLockRefPtr<AnonymousVMObject> vm_object, AsyncBlockDeviceRequest& request, size_t device_block_size)
diff --git a/Kernel/Memory/ScatterGatherList.h b/Kernel/Memory/ScatterGatherList.h
index bcd2e496ce..d6920f025b 100644
--- a/Kernel/Memory/ScatterGatherList.h
+++ b/Kernel/Memory/ScatterGatherList.h
@@ -19,7 +19,7 @@ namespace Kernel::Memory {
 
 class ScatterGatherList final : public AtomicRefCounted<ScatterGatherList> {
 public:
-    static LockRefPtr<ScatterGatherList> try_create(AsyncBlockDeviceRequest&, Span<NonnullRefPtr<PhysicalPage>> allocated_pages, size_t device_block_size);
+    static ErrorOr<LockRefPtr<ScatterGatherList>> try_create(AsyncBlockDeviceRequest&, Span<NonnullRefPtr<PhysicalPage>> allocated_pages, size_t device_block_size);
     VMObject const& vmobject() const { return m_vm_object; }
     VirtualAddress dma_region() const { return m_dma_region->vaddr(); }
     size_t scatters_count() const { return m_vm_object->physical_pages().size(); }