Kernel/Graphics: Force VirtIO Framebuffer to inherit FramebufferDevice

The distinction is not justified because a VirtIO Framebuffer device
acts much more like a regular FramebufferDevice than a pure BlockDevice.

Kernel/Graphics/FramebufferDevice.cpp

@@ -99,6 +99,13 @@ UNMAP_AFTER_INIT KResult FramebufferDevice::initialize()
     return KSuccess;
 }
 
+UNMAP_AFTER_INIT FramebufferDevice::FramebufferDevice(const GraphicsDevice& adapter, size_t output_port_index)
+    : BlockDevice(29, GraphicsManagement::the().allocate_minor_device_number())
+    , m_output_port_index(output_port_index)
+    , m_graphics_adapter(adapter)
+{
+}
+
 UNMAP_AFTER_INIT FramebufferDevice::FramebufferDevice(const GraphicsDevice& adapter, size_t output_port_index, PhysicalAddress addr, size_t width, size_t height, size_t pitch)
     : BlockDevice(29, GraphicsManagement::the().allocate_minor_device_number())
     , m_framebuffer_address(addr)

Kernel/Graphics/FramebufferDevice.h

@@ -34,6 +34,9 @@ public:
     virtual ~FramebufferDevice() {};
     KResult initialize();
 
+protected:
+    FramebufferDevice(const GraphicsDevice&, size_t);
+
 private:
     FramebufferDevice(const GraphicsDevice&, size_t, PhysicalAddress, size_t, size_t, size_t);
 

Kernel/Graphics/VirtIOGPU/FramebufferDevice.cpp

@@ -10,8 +10,8 @@
 
 namespace Kernel::Graphics::VirtIOGPU {
 
-FramebufferDevice::FramebufferDevice(GPU& virtio_gpu, ScanoutID scanout)
-    : BlockDevice(29, GraphicsManagement::the().allocate_minor_device_number())
+FramebufferDevice::FramebufferDevice(GraphicsDevice const& adapter, GPU& virtio_gpu, ScanoutID scanout)
+    : Kernel::FramebufferDevice(adapter, scanout.value())
     , m_gpu(virtio_gpu)
     , m_scanout(scanout)
 {

Kernel/Graphics/VirtIOGPU/FramebufferDevice.h

@@ -8,12 +8,13 @@
 
 #include <Kernel/Bus/VirtIO/Device.h>
 #include <Kernel/Bus/VirtIO/Queue.h>
-#include <Kernel/Devices/BlockDevice.h>
+#include <Kernel/Graphics/FramebufferDevice.h>
+#include <Kernel/Graphics/GraphicsDevice.h>
 #include <Kernel/Graphics/VirtIOGPU/GPU.h>
 
 namespace Kernel::Graphics::VirtIOGPU {
 
-class FramebufferDevice final : public BlockDevice {
+class FramebufferDevice final : public Kernel::FramebufferDevice {
     friend class Console;
     struct Buffer {
         size_t framebuffer_offset { 0 };
@@ -23,7 +24,7 @@ class FramebufferDevice final : public BlockDevice {
     };
 
 public:
-    FramebufferDevice(VirtIOGPU::GPU& virtio_gpu, ScanoutID);
+    FramebufferDevice(GraphicsDevice const&, VirtIOGPU::GPU& virtio_gpu, ScanoutID);
     virtual ~FramebufferDevice() override;
 
     virtual void deactivate_writes();
@@ -62,11 +63,6 @@ private:
 
     virtual KResult ioctl(OpenFileDescription&, unsigned request, Userspace<void*> arg) override;
     virtual KResultOr<Memory::Region*> mmap(Process&, OpenFileDescription&, Memory::VirtualRange const&, u64 offset, int prot, bool shared) override;
-    virtual bool can_read(const OpenFileDescription&, size_t) const override { return true; }
-    virtual KResultOr<size_t> read(OpenFileDescription&, u64, UserOrKernelBuffer&, size_t) override { return EINVAL; }
-    virtual bool can_write(const OpenFileDescription&, size_t) const override { return true; }
-    virtual KResultOr<size_t> write(OpenFileDescription&, u64, const UserOrKernelBuffer&, size_t) override { return EINVAL; };
-    virtual void start_request(AsyncBlockDeviceRequest& request) override { request.complete(AsyncDeviceRequest::Failure); }
 
     static bool is_valid_buffer_index(int buffer_index)
     {

Kernel/Graphics/VirtIOGPU/GPU.cpp

@@ -46,8 +46,9 @@ void GPU::initialize()
     }
 }
 
-GPU::GPU(PCI::DeviceIdentifier const& device_identifier)
+GPU::GPU(GraphicsDevice const& adapter, PCI::DeviceIdentifier const& device_identifier)
     : VirtIO::Device(device_identifier)
+    , m_adapter(adapter)
 {
     auto region_or_error = MM.allocate_contiguous_kernel_region(32 * PAGE_SIZE, "VirtGPU Scratch Space", Memory::Region::Access::ReadWrite);
     if (region_or_error.is_error())
@@ -63,7 +64,7 @@ void GPU::create_framebuffer_devices()
 {
     for (size_t i = 0; i < min(m_num_scanouts, VIRTIO_GPU_MAX_SCANOUTS); i++) {
         auto& scanout = m_scanouts[i];
-        scanout.framebuffer = adopt_ref(*new VirtIOGPU::FramebufferDevice(*this, i));
+        scanout.framebuffer = adopt_ref(*new VirtIOGPU::FramebufferDevice(*m_adapter, *this, i));
         scanout.framebuffer->after_inserting();
         scanout.console = Kernel::Graphics::VirtIOGPU::Console::initialize(scanout.framebuffer);
     }

Kernel/Graphics/VirtIOGPU/GPU.h

@@ -11,6 +11,7 @@
 #include <Kernel/Bus/VirtIO/Device.h>
 #include <Kernel/Bus/VirtIO/Queue.h>
 #include <Kernel/Devices/BlockDevice.h>
+#include <Kernel/Graphics/GraphicsDevice.h>
 #include <Kernel/Graphics/VirtIOGPU/Protocol.h>
 
 #define VIRTIO_GPU_F_VIRGL (1 << 0)
@@ -40,7 +41,7 @@ class GPU final
     friend class FramebufferDevice;
 
 public:
-    GPU(PCI::DeviceIdentifier const&);
+    GPU(GraphicsDevice const&, PCI::DeviceIdentifier const&);
     virtual ~GPU() override;
 
     void create_framebuffer_devices();
@@ -119,6 +120,8 @@ private:
     VirtIO::Configuration const* m_device_configuration { nullptr };
     ResourceID m_resource_id_counter { 0 };
 
+    NonnullRefPtr<GraphicsDevice> m_adapter;
+
     // Synchronous commands
     WaitQueue m_outstanding_request;
     Mutex m_operation_lock;

Kernel/Graphics/VirtIOGPU/GraphicsAdapter.cpp

@@ -22,7 +22,7 @@ NonnullRefPtr<GraphicsAdapter> GraphicsAdapter::initialize(PCI::DeviceIdentifier
 GraphicsAdapter::GraphicsAdapter(PCI::DeviceIdentifier const& device_identifier)
     : PCI::Device(device_identifier.address())
 {
-    m_gpu_device = adopt_ref(*new GPU(device_identifier)).leak_ref();
+    m_gpu_device = adopt_ref(*new GPU(*this, device_identifier)).leak_ref();
     m_gpu_device->initialize();
 }