Kernel/Interrupts: Return boolean on whether we handled the interrupt

If we are in a shared interrupt handler, the called handlers might
indicate it was not their interrupt, so we should not increment the
call counter of these handlers.

2 files changed, 10 insertions, 5 deletions

diff --git a/Kernel/VirtIO/VirtIO.cpp b/Kernel/VirtIO/VirtIO.cpp
index fcc20071fd..ba6b95f1a6 100644
--- a/Kernel/VirtIO/VirtIO.cpp
+++ b/Kernel/VirtIO/VirtIO.cpp
@@ -342,11 +342,13 @@ u8 VirtIODevice::isr_status()
     return config_read8(*m_isr_cfg, 0);
 }
 
-void VirtIODevice::handle_irq(const RegisterState&)
+bool VirtIODevice::handle_irq(const RegisterState&)
 {
     u8 isr_type = isr_status();
-    if ((isr_type & (QUEUE_INTERRUPT | DEVICE_CONFIG_INTERRUPT)) == 0)
+    if ((isr_type & (QUEUE_INTERRUPT | DEVICE_CONFIG_INTERRUPT)) == 0) {
         dbgln_if(VIRTIO_DEBUG, "{}: Handling interrupt with unknown type: {}", m_class_name, isr_type);
+        return false;
+    }
     if (isr_type & DEVICE_CONFIG_INTERRUPT) {
         dbgln_if(VIRTIO_DEBUG, "{}: VirtIO Device config interrupt!", m_class_name);
         if (!handle_device_config_change()) {
@@ -357,11 +359,14 @@ void VirtIODevice::handle_irq(const RegisterState&)
     if (isr_type & QUEUE_INTERRUPT) {
         dbgln_if(VIRTIO_DEBUG, "{}: VirtIO Queue interrupt!", m_class_name);
         for (size_t i = 0; i < m_queues.size(); i++) {
-            if (get_queue(i).new_data_available())
-                return handle_queue_update(i);
+            if (get_queue(i).new_data_available()) {
+                handle_queue_update(i);
+                return true;
+            }
         }
         dbgln_if(VIRTIO_DEBUG, "{}: Got queue interrupt but all queues are up to date!", m_class_name);
     }
+    return true;
 }
 
 void VirtIODevice::supply_chain_and_notify(u16 queue_index, VirtIOQueueChain& chain)
diff --git a/Kernel/VirtIO/VirtIO.h b/Kernel/VirtIO/VirtIO.h
index 9fe71637a7..9b49926722 100644
--- a/Kernel/VirtIO/VirtIO.h
+++ b/Kernel/VirtIO/VirtIO.h
@@ -222,7 +222,7 @@ private:
     void reset_device();
 
     u8 isr_status();
-    virtual void handle_irq(const RegisterState&) override;
+    virtual bool handle_irq(const RegisterState&) override;
 
     NonnullOwnPtrVector<VirtIOQueue> m_queues;
     NonnullOwnPtrVector<Configuration> m_configs;