Kernel: Replace IRQHandler with the new InterruptHandler class

System components that need an IRQ handling are now inheriting the
InterruptHandler class.

In addition to that, the initialization process of PATAChannel was
changed to fit the changes.
PATAChannel, E1000NetworkAdapter and RTL8139NetworkAdapter are now
inheriting from PCI::Device instead of InterruptHandler directly.

29 files changed, 193 insertions, 169 deletions

diff --git a/Kernel/ACPI/ACPIDynamicParser.cpp b/Kernel/ACPI/ACPIDynamicParser.cpp
index 52084e7e94..2a2a75744a 100644
--- a/Kernel/ACPI/ACPIDynamicParser.cpp
+++ b/Kernel/ACPI/ACPIDynamicParser.cpp
@@ -41,20 +41,20 @@ void ACPIDynamicParser::initialize_without_rsdp()
 }
 
 ACPIDynamicParser::ACPIDynamicParser()
-    : IRQHandler(9)
+    : InterruptHandler(9)
     , ACPIStaticParser()
 
 {
     kprintf("ACPI: Dynamic Parsing Enabled, Can parse AML\n");
 }
 ACPIDynamicParser::ACPIDynamicParser(ACPI_RAW::RSDPDescriptor20& rsdp)
-    : IRQHandler(9)
+    : InterruptHandler(9)
     , ACPIStaticParser(rsdp)
 {
     kprintf("ACPI: Dynamic Parsing Enabled, Can parse AML\n");
 }
 
-void ACPIDynamicParser::handle_irq()
+void ACPIDynamicParser::handle_interrupt()
 {
     // FIXME: Implement IRQ handling of ACPI signals!
     ASSERT_NOT_REACHED();
@@ -90,4 +90,4 @@ void ACPIDynamicParser::build_namespace()
 {
     // FIXME: Implement AML Interpretation to build the ACPI namespace
     ASSERT_NOT_REACHED();
-}
\ No newline at end of file
+}
diff --git a/Kernel/ACPI/ACPIDynamicParser.h b/Kernel/ACPI/ACPIDynamicParser.h
index eb87f18fc8..a4dee415fc 100644
--- a/Kernel/ACPI/ACPIDynamicParser.h
+++ b/Kernel/ACPI/ACPIDynamicParser.h
@@ -29,12 +29,12 @@
 #include <AK/RefPtr.h>
 #include <Kernel/ACPI/ACPIStaticParser.h>
 #include <Kernel/Devices/DiskDevice.h>
-#include <Kernel/IRQHandler.h>
+#include <Kernel/InterruptHandler.h>
 #include <Kernel/Lock.h>
 #include <Kernel/VM/PhysicalAddress.h>
 #include <Kernel/VM/PhysicalPage.h>
 
-class ACPIDynamicParser final : public IRQHandler
+class ACPIDynamicParser final : public InterruptHandler
     , ACPIStaticParser {
 public:
     static void initialize(ACPI_RAW::RSDPDescriptor20& rsdp);
@@ -53,7 +53,7 @@ protected:
 private:
     void build_namespace();
     // ^IRQHandler
-    virtual void handle_irq() override;
+    virtual void handle_interrupt() override;
 
     OwnPtr<Region> m_acpi_namespace;
-};
\ No newline at end of file
+};
diff --git a/Kernel/Arch/i386/CPU.cpp b/Kernel/Arch/i386/CPU.cpp
index d1ef90e6a4..56d9aaf8d8 100644
--- a/Kernel/Arch/i386/CPU.cpp
+++ b/Kernel/Arch/i386/CPU.cpp
@@ -26,12 +26,12 @@
 
 #include "APIC.h"
 #include "Assertions.h"
-#include "IRQHandler.h"
 #include "PIC.h"
 #include "Process.h"
 #include <AK/Types.h>
 #include <Kernel/Arch/i386/CPU.h>
 #include <Kernel/KSyms.h>
+#include <Kernel/SharedInterruptHandler.h>
 #include <Kernel/VM/MemoryManager.h>
 #include <LibC/mallocdefs.h>
 
@@ -48,7 +48,7 @@ static DescriptorTablePointer s_gdtr;
 static Descriptor s_idt[256];
 static Descriptor s_gdt[256];
 
-static IRQHandler* s_irq_handler[16];
+static SharedInterruptHandler* s_irq_handler[256];
 
 static Vector<u16>* s_gdt_freelist;
 
@@ -435,18 +435,25 @@ static void unimp_trap()
     hang();
 }
 
-void register_irq_handler(u8 irq, IRQHandler& handler)
+void register_shared_interrupt_handler(u8 irq, SharedInterruptHandler& handler)
 {
     ASSERT(!s_irq_handler[irq]);
     s_irq_handler[irq] = &handler;
 }
 
-void unregister_irq_handler(u8 irq, IRQHandler& handler)
+void unregister_shared_interrupt_handler(u8 irq, SharedInterruptHandler& handler)
 {
     ASSERT(s_irq_handler[irq] == &handler);
     s_irq_handler[irq] = nullptr;
 }
 
+SharedInterruptHandler& get_interrupt_handler(u8 number)
+{
+    ASSERT(number < 256);
+    ASSERT(s_irq_handler[number] != nullptr);
+    return *s_irq_handler[number];
+}
+
 void register_interrupt_handler(u8 index, void (*f)())
 {
     s_idt[index].low = 0x00080000 | LSW((f));
@@ -524,8 +531,8 @@ void idt_init()
     register_interrupt_handler(0x5e, irq_14_asm_entry);
     register_interrupt_handler(0x5f, irq_15_asm_entry);
 
-    for (u8 i = 0; i < 16; ++i) {
-        s_irq_handler[i] = nullptr;
+    for (u8 i = 0; i < 255; ++i) {
+        SharedInterruptHandler::initialize(i);
     }
 
     flush_idt();
@@ -541,8 +548,9 @@ void handle_irq(RegisterDump regs)
     clac();
     ASSERT(regs.isr_number >= 0x50 && regs.isr_number <= 0x5f);
     u8 irq = (u8)(regs.isr_number - 0x50);
-    if (s_irq_handler[irq])
-        s_irq_handler[irq]->handle_irq();
+    ASSERT(s_irq_handler[irq] != nullptr);
+    s_irq_handler[irq]->handle_interrupt();
+    // FIXME: Determine if we use IRQs or MSIs (in the future) to send EOI...
     PIC::eoi(irq);
 }
 
diff --git a/Kernel/Arch/i386/CPU.h b/Kernel/Arch/i386/CPU.h
index 11fb73881c..3eebbc3156 100644
--- a/Kernel/Arch/i386/CPU.h
+++ b/Kernel/Arch/i386/CPU.h
@@ -240,7 +240,7 @@ public:
     u64 raw[4];
 };
 
-class IRQHandler;
+class SharedInterruptHandler;
 struct RegisterDump;
 
 void gdt_init();
@@ -248,8 +248,9 @@ void idt_init();
 void sse_init();
 void register_interrupt_handler(u8 number, void (*f)());
 void register_user_callable_interrupt_handler(u8 number, void (*f)());
-void register_irq_handler(u8 number, IRQHandler&);
-void unregister_irq_handler(u8 number, IRQHandler&);
+void register_shared_interrupt_handler(u8 number, SharedInterruptHandler&);
+SharedInterruptHandler& get_interrupt_handler(u8 number);
+void unregister_shared_interrupt_handler(u8 number, SharedInterruptHandler&);
 void flush_idt();
 void flush_gdt();
 void load_task_register(u16 selector);
diff --git a/Kernel/Arch/i386/PIC.cpp b/Kernel/Arch/i386/PIC.cpp
index 2b62494b5a..c500ef8c95 100644
--- a/Kernel/Arch/i386/PIC.cpp
+++ b/Kernel/Arch/i386/PIC.cpp
@@ -75,6 +75,20 @@ void enable(u8 irq)
     }
 }
 
+bool is_enabled(u8 irq)
+{
+    InterruptDisabler disabler;
+    u8 imr;
+    if (irq & 8) {
+        imr = IO::in8(PIC1_CMD);
+        imr &= (1 << (irq - 8));
+    } else {
+        imr = IO::in8(PIC0_CMD);
+        imr &= (1 << irq);
+    }
+    return (!!imr);
+}
+
 void eoi(u8 irq)
 {
     if (irq & 8)
diff --git a/Kernel/Arch/i386/PIC.h b/Kernel/Arch/i386/PIC.h
index ecac1c3101..4746fb4a4b 100644
--- a/Kernel/Arch/i386/PIC.h
+++ b/Kernel/Arch/i386/PIC.h
@@ -34,6 +34,7 @@ void enable(u8 number);
 void disable(u8 number);
 void eoi(u8 number);
 void initialize();
+bool is_enabled(u8 number);
 u16 get_isr();
 u16 get_irr();
 
diff --git a/Kernel/Devices/BlockDevice.h b/Kernel/Devices/BlockDevice.h
index fd8c2fb495..483ca90fd9 100644
--- a/Kernel/Devices/BlockDevice.h
+++ b/Kernel/Devices/BlockDevice.h
@@ -34,10 +34,9 @@ public:
 
     size_t block_size() const { return m_block_size; }
     virtual bool is_seekable() const override { return true; }
-
 protected:
     BlockDevice(unsigned major, unsigned minor, size_t block_size = PAGE_SIZE)
-        : Device(major, minor)
+        : Device(major, minor, (u8)DEVICE_TYPE::BLOCK_DEVICE)
         , m_block_size(block_size)
     {
     }
diff --git a/Kernel/Devices/CharacterDevice.h b/Kernel/Devices/CharacterDevice.h
index 6d52eed55e..09fd7f92e8 100644
--- a/Kernel/Devices/CharacterDevice.h
+++ b/Kernel/Devices/CharacterDevice.h
@@ -34,7 +34,7 @@ public:
 
 protected:
     CharacterDevice(unsigned major, unsigned minor)
-        : Device(major, minor)
+        : Device(major, minor, (u8)DEVICE_TYPE::CHAR_DEVICE)
     {
     }
 
diff --git a/Kernel/Devices/Device.cpp b/Kernel/Devices/Device.cpp
index 833e9da0f3..09b1419d1c 100644
--- a/Kernel/Devices/Device.cpp
+++ b/Kernel/Devices/Device.cpp
@@ -25,48 +25,32 @@
  */
 
 #include <Kernel/Devices/Device.h>
-#include <Kernel/FileSystem/InodeMetadata.h>
+#include <Kernel/Devices/HardwareEventsManager.h>
 #include <LibC/errno_numbers.h>
 
-static HashMap<u32, Device*>* s_all_devices;
-
-HashMap<u32, Device*>& Device::all_devices()
-{
-    if (s_all_devices == nullptr)
-        s_all_devices = new HashMap<u32, Device*>;
-    return *s_all_devices;
-}
-
 void Device::for_each(Function<void(Device&)> callback)
 {
-    for (auto& entry : all_devices())
-        callback(*entry.value);
+    for (auto* entry : HardwareEventsManager::the().get_devices_list()) {
+        ASSERT(entry != nullptr);
+        callback(*entry);
+    }
 }
 
 Device* Device::get_device(unsigned major, unsigned minor)
 {
-    auto it = all_devices().find(encoded_device(major, minor));
-    if (it == all_devices().end())
-        return nullptr;
-    return it->value;
+    return HardwareEventsManager::the().get_device(major, minor);
 }
 
-Device::Device(unsigned major, unsigned minor)
+Device::Device(unsigned major, unsigned minor, u8 device_type)
     : m_major(major)
     , m_minor(minor)
 {
-    u32 device_id = encoded_device(major, minor);
-    auto it = all_devices().find(device_id);
-    if (it != all_devices().end()) {
-        dbg() << "Already registered " << major << "," << minor << ": " << it->value->class_name();
-    }
-    ASSERT(!all_devices().contains(device_id));
-    all_devices().set(device_id, this);
+    HardwareEventsManager::the().register_device(*this, device_type);
 }
 
 Device::~Device()
 {
-    all_devices().remove(encoded_device(m_major, m_minor));
+    HardwareEventsManager::the().unregister_device(*this);
 }
 
 String Device::absolute_path() const
diff --git a/Kernel/Devices/Device.h b/Kernel/Devices/Device.h
index 2ddd7720c8..4aadf49a9a 100644
--- a/Kernel/Devices/Device.h
+++ b/Kernel/Devices/Device.h
@@ -39,6 +39,11 @@
 #include <Kernel/FileSystem/File.h>
 #include <Kernel/UnixTypes.h>
 
+enum class DEVICE_TYPE {
+    BLOCK_DEVICE = 1,
+    CHAR_DEVICE = 2
+};
+
 class Device : public File {
 public:
     virtual ~Device() override;
@@ -55,16 +60,17 @@ public:
     virtual bool is_device() const override { return true; }
     virtual bool is_disk_device() const { return false; }
 
+    virtual bool is_block_device() const override { return false; }
+    virtual bool is_character_device() const override { return true; }
+
     static void for_each(Function<void(Device&)>);
     static Device* get_device(unsigned major, unsigned minor);
 
 protected:
-    Device(unsigned major, unsigned minor);
+    Device(unsigned major, unsigned minor, u8 device_type);
     void set_uid(uid_t uid) { m_uid = uid; }
     void set_gid(gid_t gid) { m_gid = gid; }
 
-    static HashMap<u32, Device*>& all_devices();
-
 private:
     unsigned m_major { 0 };
     unsigned m_minor { 0 };
diff --git a/Kernel/Devices/FloppyDiskDevice.cpp b/Kernel/Devices/FloppyDiskDevice.cpp
index 9cd38c31ab..adee42eaa7 100644
--- a/Kernel/Devices/FloppyDiskDevice.cpp
+++ b/Kernel/Devices/FloppyDiskDevice.cpp
@@ -109,7 +109,7 @@ const char* FloppyDiskDevice::class_name() const
 }
 
 FloppyDiskDevice::FloppyDiskDevice(FloppyDiskDevice::DriveType type)
-    : IRQHandler(IRQ_FLOPPY_DRIVE)
+    : InterruptHandler(IRQ_FLOPPY_DRIVE)
     , DiskDevice(89, (type == FloppyDiskDevice::DriveType::Master) ? 0 : 1, BYTES_PER_SECTOR)
     , m_io_base_addr((type == FloppyDiskDevice::DriveType::Master) ? 0x3F0 : 0x370)
 {
@@ -167,7 +167,7 @@ bool FloppyDiskDevice::read_sectors_with_dma(u16 lba, u16 count, u8* outbuf)
     //while(start < PIT::seconds_since_boot() + 1)
     //    ;
 
-    disable_irq();
+    disable_interrupts();
 
     IO::out8(0xA, FLOPPY_DMA_CHANNEL | 0x4); // Channel 2 SEL, MASK_ON = 1
     IO::out8(0x0B, 0x56);                    // Begin DMA, Single Transfer, Increment, Auto, FDC -> RAM, Channel 2
@@ -195,7 +195,7 @@ bool FloppyDiskDevice::read_sectors_with_dma(u16 lba, u16 count, u8* outbuf)
         send_byte(0x1b); // GPL3 value. The Datasheet doesn't really specify the values for this properly...
         send_byte(0xff);
 
-        enable_irq();
+        enable_interrupts();
 
         wait_for_irq(); // TODO: See if there was a lockup here via some "timeout counter"
         m_interrupted = false;
@@ -269,7 +269,7 @@ bool FloppyDiskDevice::write_sectors_with_dma(u16 lba, u16 count, const u8* inbu
     //while(start < PIT::seconds_since_boot() + 1)
     //    ;
 
-    disable_irq();
+    disable_interrupts();
 
     IO::out8(0xA, FLOPPY_DMA_CHANNEL | 0x4); // Channel 2 SEL, MASK_ON = 1
     IO::out8(0x0B, 0x5A);                    // Begin DMA, Single Transfer, Increment, Auto, RAM -> FDC, Channel 2
@@ -295,7 +295,7 @@ bool FloppyDiskDevice::write_sectors_with_dma(u16 lba, u16 count, const u8* inbu
         send_byte(0x1b); // GPL3 value. The Datasheet doesn't really specify the values for this properly...
         send_byte(0xff);
 
-        enable_irq();
+        enable_interrupts();
 
         wait_for_irq(); // TODO: See if there was a lockup here via some "timeout counter"
         m_interrupted = false;
@@ -358,7 +358,7 @@ bool FloppyDiskDevice::wait_for_irq()
     return true;
 }
 
-void FloppyDiskDevice::handle_irq()
+void FloppyDiskDevice::handle_interrupt()
 {
     // The only thing we need to do is acknowledge the IRQ happened
     m_interrupted = true;
@@ -512,7 +512,7 @@ void FloppyDiskDevice::initialize()
     kprintf("fdc: m_io_base = 0x%x IRQn = %d\n", m_io_base_addr, IRQ_FLOPPY_DRIVE);
 #endif
 
-    enable_irq();
+    enable_interrupts();
 
     // Get the version of the Floppy Disk Controller
     send_byte(FloppyCommand::Version);
diff --git a/Kernel/Devices/FloppyDiskDevice.h b/Kernel/Devices/FloppyDiskDevice.h
index a505bc027c..b2349387bb 100644
--- a/Kernel/Devices/FloppyDiskDevice.h
+++ b/Kernel/Devices/FloppyDiskDevice.h
@@ -101,7 +101,7 @@
 
 #include <AK/RefPtr.h>
 #include <Kernel/Devices/DiskDevice.h>
-#include <Kernel/IRQHandler.h>
+#include <Kernel/InterruptHandler.h>
 #include <Kernel/Lock.h>
 #include <Kernel/VM/PhysicalAddress.h>
 #include <Kernel/VM/PhysicalPage.h>
@@ -122,7 +122,7 @@ struct FloppyControllerCommand {
 // uses the Intel 82077A controller. More about this controller can
 // be found here: http://www.buchty.net/casio/files/82077.pdf
 //
-class FloppyDiskDevice final : public IRQHandler
+class FloppyDiskDevice final : public InterruptHandler
     , public DiskDevice {
     AK_MAKE_ETERNAL
 
@@ -178,7 +178,7 @@ protected:
 
 private:
     // ^IRQHandler
-    void handle_irq();
+    void handle_interrupt();
 
     // ^DiskDevice
     virtual const char* class_name() const override;
diff --git a/Kernel/IRQHandler.cpp b/Kernel/Devices/HardwareEventsManager.cpp
index 0a2ff3aeb5..f586ee0322 100644
--- a/Kernel/IRQHandler.cpp
+++ b/Kernel/Devices/HardwareEventsManager.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -24,27 +24,42 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "IRQHandler.h"
-#include <Kernel/Arch/i386/CPU.h>
-#include <Kernel/Arch/i386/PIC.h>
+#include <Kernel/Devices/HardwareEventsManager.h>
 
-IRQHandler::IRQHandler(u8 irq)
-    : m_irq_number(irq)
+static HardwareEventsManager* s_hardware_events_manager;
+
+HardwareEventsManager& HardwareEventsManager::the()
+{
+    if (s_hardware_events_manager == nullptr) {
+        s_hardware_events_manager = new HardwareEventsManager();
+    }
+    return *s_hardware_events_manager;
+}
+
+HashTable<Device*>& HardwareEventsManager::get_devices_list()
 {
-    register_irq_handler(m_irq_number, *this);
+    return m_devices;
 }
 
-IRQHandler::~IRQHandler()
+void HardwareEventsManager::unregister_device(Device& device)
 {
-    unregister_irq_handler(m_irq_number, *this);
+    get_devices_list().remove(&device);
 }
 
-void IRQHandler::enable_irq()
+HardwareEventsManager::HardwareEventsManager()
 {
-    PIC::enable(m_irq_number);
 }
 
-void IRQHandler::disable_irq()
+Device* HardwareEventsManager::get_device(unsigned major, unsigned minor)
+{
+    for (auto* entry : HardwareEventsManager::get_devices_list()) {
+        ASSERT(entry != nullptr);
+        if (entry->major() == major && entry->minor() == minor)
+            return entry;
+    }
+    return nullptr;
+}
+void HardwareEventsManager::register_device(Device& device, u8)
 {
-    PIC::disable(m_irq_number);
+    get_devices_list().set(&device);
 }
diff --git a/Kernel/IRQHandler.h b/Kernel/Devices/HardwareEventsManager.h
index dbf0821704..b8b6c1f112 100644
--- a/Kernel/IRQHandler.h
+++ b/Kernel/Devices/HardwareEventsManager.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,20 +27,18 @@
 #pragma once
 
 #include <AK/Types.h>
+#include <Kernel/Devices/Device.h>
 
-class IRQHandler {
+class HardwareEventsManager {
 public:
-    virtual ~IRQHandler();
-    virtual void handle_irq() = 0;
-
-    u8 irq_number() const { return m_irq_number; }
-
-    void enable_irq();
-    void disable_irq();
-
-protected:
-    explicit IRQHandler(u8 irq);
+    static HardwareEventsManager& the();
+    void register_device(Device&, u8);
+    void unregister_device(Device&);
+    void register_device_event();
+    Device* get_device(unsigned, unsigned);
+    HashTable<Device*>& get_devices_list();
 
 private:
-    u8 m_irq_number { 0 };
+    HashTable<Device*> m_devices;
+    HardwareEventsManager();
 };
diff --git a/Kernel/Devices/KeyboardDevice.cpp b/Kernel/Devices/KeyboardDevice.cpp
index 86c862057e..5996e87566 100644
--- a/Kernel/Devices/KeyboardDevice.cpp
+++ b/Kernel/Devices/KeyboardDevice.cpp
@@ -483,7 +483,7 @@ void KeyboardDevice::key_state_changed(u8 raw, bool pressed)
     m_has_e0_prefix = false;
 }
 
-void KeyboardDevice::handle_irq()
+void KeyboardDevice::handle_interrupt()
 {
     for (;;) {
         u8 status = IO::in8(I8042_STATUS);
@@ -551,7 +551,7 @@ KeyboardDevice& KeyboardDevice::the()
 }
 
 KeyboardDevice::KeyboardDevice()
-    : IRQHandler(IRQ_KEYBOARD)
+    : InterruptHandler(IRQ_KEYBOARD)
     , CharacterDevice(85, 1)
 {
     s_the = this;
@@ -563,7 +563,7 @@ KeyboardDevice::KeyboardDevice()
     while (IO::in8(I8042_STATUS) & I8042_BUFFER_FULL)
         IO::in8(I8042_BUFFER);
 
-    enable_irq();
+    enable_interrupts();
 }
 
 KeyboardDevice::~KeyboardDevice()
diff --git a/Kernel/Devices/KeyboardDevice.h b/Kernel/Devices/KeyboardDevice.h
index a2c9b4e3a3..a5b24b7b2d 100644
--- a/Kernel/Devices/KeyboardDevice.h
+++ b/Kernel/Devices/KeyboardDevice.h
@@ -26,16 +26,16 @@
 
 #pragma once
 
-#include "IRQHandler.h"
 #include "KeyCode.h"
 #include <AK/CircularQueue.h>
 #include <AK/DoublyLinkedList.h>
 #include <AK/Types.h>
 #include <Kernel/Devices/CharacterDevice.h>
+#include <Kernel/InterruptHandler.h>
 
 class KeyboardClient;
 
-class KeyboardDevice final : public IRQHandler
+class KeyboardDevice final : public InterruptHandler
     , public CharacterDevice {
     AK_MAKE_ETERNAL
 public:
@@ -57,7 +57,7 @@ public:
 
 private:
     // ^IRQHandler
-    virtual void handle_irq() override;
+    virtual void handle_interrupt() override;
 
     // ^CharacterDevice
     virtual const char* class_name() const override { return "KeyboardDevice"; }
diff --git a/Kernel/Devices/PATAChannel.cpp b/Kernel/Devices/PATAChannel.cpp
index b57fe42c1c..ee67eb7ff7 100644
--- a/Kernel/Devices/PATAChannel.cpp
+++ b/Kernel/Devices/PATAChannel.cpp
@@ -112,18 +112,25 @@ static Lock& s_lock()
     return *lock;
 };
 
-OwnPtr<PATAChannel> PATAChannel::create(ChannelType type, bool force_pio)
+OwnPtr<PATAChannel> PATAChannel::autodetect(ChannelType type, bool force_pio)
 {
-    return make<PATAChannel>(type, force_pio);
+    PCI::Address found_address;
+    PCI::enumerate_all([&](const PCI::Address& address, PCI::ID id) {
+        if (PCI::get_class(address) == PCI_Mass_Storage_Class && PCI::get_subclass(address) == PCI_IDE_Controller_Subclass) {
+            found_address = address;
+            kprintf("PATAChannel: PATA Controller found! id=%w:%w\n", id.vendor_id, id.device_id);
+        }
+    });
+    return make<PATAChannel>(found_address, type, force_pio);
 }
 
-PATAChannel::PATAChannel(ChannelType type, bool force_pio)
-    : IRQHandler((type == ChannelType::Primary ? PATA_PRIMARY_IRQ : PATA_SECONDARY_IRQ))
+PATAChannel::PATAChannel(PCI::Address pci_address, ChannelType type, bool force_pio)
+    : PCI::Device(pci_address, (type == ChannelType::Primary ? PATA_PRIMARY_IRQ : PATA_SECONDARY_IRQ))
     , m_channel_number((type == ChannelType::Primary ? 0 : 1))
     , m_io_base((type == ChannelType::Primary ? 0x1F0 : 0x170))
     , m_control_base((type == ChannelType::Primary ? 0x3f6 : 0x376))
 {
-    disable_irq();
+    disable_interrupts();
 
     m_dma_enabled.resource() = true;
     ProcFS::add_sys_bool("ide_dma", m_dma_enabled);
@@ -140,14 +147,8 @@ PATAChannel::~PATAChannel()
 
 void PATAChannel::initialize(bool force_pio)
 {
-    PCI::enumerate_all([this](const PCI::Address& address, PCI::ID id) {
-        if (PCI::get_class(address) == PCI_Mass_Storage_Class && PCI::get_subclass(address) == PCI_IDE_Controller_Subclass) {
-            m_pci_address = address;
-            kprintf("PATAChannel: PATA Controller found! id=%w:%w\n", id.vendor_id, id.device_id);
-        }
-    });
 
-    if (m_pci_address.is_null()) {
+    if (get_pci_address().is_null()) {
         kprintf("PATAChannel: PCI address was null; can not set up DMA\n");
         return;
     }
@@ -158,9 +159,9 @@ void PATAChannel::initialize(bool force_pio)
     }
 
     // Let's try to set up DMA transfers.
-    PCI::enable_bus_mastering(m_pci_address);
+    PCI::enable_bus_mastering(get_pci_address());
     prdt().end_of_table = 0x8000;
-    m_bus_master_base = PCI::get_BAR4(m_pci_address) & 0xfffc;
+    m_bus_master_base = PCI::get_BAR4(get_pci_address()) & 0xfffc;
     m_dma_buffer_page = MM.allocate_supervisor_physical_page();
     kprintf("PATAChannel: Bus master IDE: I/O @ %x\n", m_bus_master_base);
 }
@@ -181,12 +182,11 @@ static void print_ide_status(u8 status)
 void PATAChannel::wait_for_irq()
 {
     cli();
-    enable_irq();
+    InterruptHandler::Enabler enabler(*this);
     current->wait_on(m_irq_queue);
-    disable_irq();
 }
 
-void PATAChannel::handle_irq()
+void PATAChannel::handle_interrupt()
 {
     u8 status = IO::in8(m_io_base + ATA_REG_STATUS);
     if (status & ATA_SR_ERR) {
diff --git a/Kernel/Devices/PATAChannel.h b/Kernel/Devices/PATAChannel.h
index 829def7558..cee50d3928 100644
--- a/Kernel/Devices/PATAChannel.h
+++ b/Kernel/Devices/PATAChannel.h
@@ -38,9 +38,10 @@
 
 #include <AK/OwnPtr.h>
 #include <AK/RefPtr.h>
-#include <Kernel/IRQHandler.h>
+#include <Kernel/InterruptHandler.h>
 #include <Kernel/Lock.h>
 #include <Kernel/PCI/Access.h>
+#include <Kernel/PCI/Device.h>
 #include <Kernel/VM/PhysicalAddress.h>
 #include <Kernel/VM/PhysicalPage.h>
 #include <Kernel/WaitQueue.h>
@@ -52,7 +53,7 @@ struct PhysicalRegionDescriptor {
 };
 
 class PATADiskDevice;
-class PATAChannel final : public IRQHandler {
+class PATAChannel final : public PCI::Device {
     friend class PATADiskDevice;
     AK_MAKE_ETERNAL
 public:
@@ -62,8 +63,8 @@ public:
     };
 
 public:
-    static OwnPtr<PATAChannel> create(ChannelType type, bool force_pio);
-    PATAChannel(ChannelType type, bool force_pio);
+    static OwnPtr<PATAChannel> autodetect(ChannelType type, bool force_pio);
+    PATAChannel(PCI::Address pci_address, ChannelType type, bool force_pio);
     virtual ~PATAChannel() override;
 
     RefPtr<PATADiskDevice> master_device() { return m_master; };
@@ -71,7 +72,7 @@ public:
 
 private:
     //^ IRQHandler
-    virtual void handle_irq() override;
+    virtual void handle_interrupt() override;
 
     void initialize(bool force_pio);
     void detect_disks();
@@ -90,7 +91,6 @@ private:
 
     WaitQueue m_irq_queue;
 
-    PCI::Address m_pci_address;
     PhysicalRegionDescriptor& prdt() { return *reinterpret_cast<PhysicalRegionDescriptor*>(m_prdt_page->paddr().offset(0xc0000000).as_ptr()); }
     RefPtr<PhysicalPage> m_prdt_page;
     RefPtr<PhysicalPage> m_dma_buffer_page;
diff --git a/Kernel/Devices/PATADiskDevice.h b/Kernel/Devices/PATADiskDevice.h
index 086c6d8467..d99de6518f 100644
--- a/Kernel/Devices/PATADiskDevice.h
+++ b/Kernel/Devices/PATADiskDevice.h
@@ -31,7 +31,7 @@
 #pragma once
 
 #include <Kernel/Devices/DiskDevice.h>
-#include <Kernel/IRQHandler.h>
+#include <Kernel/InterruptHandler.h>
 #include <Kernel/Lock.h>
 
 class PATAChannel;
diff --git a/Kernel/Devices/PS2MouseDevice.cpp b/Kernel/Devices/PS2MouseDevice.cpp
index 6a1e178560..fca9320412 100644
--- a/Kernel/Devices/PS2MouseDevice.cpp
+++ b/Kernel/Devices/PS2MouseDevice.cpp
@@ -54,7 +54,7 @@
 static PS2MouseDevice* s_the;
 
 PS2MouseDevice::PS2MouseDevice()
-    : IRQHandler(IRQ_MOUSE)
+    : InterruptHandler(IRQ_MOUSE)
     , CharacterDevice(10, 1)
 {
     s_the = this;
@@ -70,7 +70,7 @@ PS2MouseDevice& PS2MouseDevice::the()
     return *s_the;
 }
 
-void PS2MouseDevice::handle_irq()
+void PS2MouseDevice::handle_interrupt()
 {
     for (;;) {
         u8 status = IO::in8(I8042_STATUS);
@@ -242,7 +242,7 @@ void PS2MouseDevice::initialize_device()
         kprintf("PS2MouseDevice: No mouse wheel detected!\n");
     }
 
-    enable_irq();
+    enable_interrupts();
 }
 
 void PS2MouseDevice::expect_ack()
diff --git a/Kernel/Devices/PS2MouseDevice.h b/Kernel/Devices/PS2MouseDevice.h
index 6010bb6cef..e806b7fa83 100644
--- a/Kernel/Devices/PS2MouseDevice.h
+++ b/Kernel/Devices/PS2MouseDevice.h
@@ -28,10 +28,10 @@
 
 #include <AK/CircularQueue.h>
 #include <Kernel/Devices/CharacterDevice.h>
-#include <Kernel/IRQHandler.h>
+#include <Kernel/InterruptHandler.h>
 #include <Kernel/MousePacket.h>
 
-class PS2MouseDevice final : public IRQHandler
+class PS2MouseDevice final : public InterruptHandler
     , public CharacterDevice {
 public:
     PS2MouseDevice();
@@ -47,7 +47,7 @@ public:
 
 private:
     // ^IRQHandler
-    virtual void handle_irq() override;
+    virtual void handle_interrupt() override;
 
     // ^CharacterDevice
     virtual const char* class_name() const override { return "PS2MouseDevice"; }
diff --git a/Kernel/Devices/SB16.cpp b/Kernel/Devices/SB16.cpp
index f015adcc10..8150aaacda 100644
--- a/Kernel/Devices/SB16.cpp
+++ b/Kernel/Devices/SB16.cpp
@@ -74,7 +74,7 @@ void SB16::set_sample_rate(uint16_t hz)
 static SB16* s_the;
 
 SB16::SB16()
-    : IRQHandler(5)
+    : InterruptHandler(5)
     , CharacterDevice(42, 42) // ### ?
 {
     s_the = this;
@@ -92,7 +92,7 @@ SB16& SB16::the()
 
 void SB16::initialize()
 {
-    disable_irq();
+    disable_interrupts();
 
     IO::out8(0x226, 1);
     IO::delay();
@@ -153,7 +153,7 @@ void SB16::dma_start(uint32_t length)
     IO::out8(0xd4, (channel % 4));
 }
 
-void SB16::handle_irq()
+void SB16::handle_interrupt()
 {
     // Stop sound output ready for the next block.
     dsp_write(0xd5);
@@ -168,9 +168,8 @@ void SB16::handle_irq()
 void SB16::wait_for_irq()
 {
     cli();
-    enable_irq();
+    InterruptHandler::Enabler enabler(*this);
     current->wait_on(m_irq_queue);
-    disable_irq();
 }
 
 ssize_t SB16::write(FileDescription&, const u8* data, ssize_t length)
diff --git a/Kernel/Devices/SB16.h b/Kernel/Devices/SB16.h
index 21df353222..25c91cf59f 100644
--- a/Kernel/Devices/SB16.h
+++ b/Kernel/Devices/SB16.h
@@ -28,14 +28,14 @@
 
 #include <AK/CircularQueue.h>
 #include <Kernel/Devices/CharacterDevice.h>
-#include <Kernel/IRQHandler.h>
+#include <Kernel/InterruptHandler.h>
 #include <Kernel/VM/PhysicalAddress.h>
 #include <Kernel/VM/PhysicalPage.h>
 #include <Kernel/WaitQueue.h>
 
 class SB16;
 
-class SB16 final : public IRQHandler
+class SB16 final : public InterruptHandler
     , public CharacterDevice {
 public:
     SB16();
@@ -51,7 +51,7 @@ public:
 
 private:
     // ^IRQHandler
-    virtual void handle_irq() override;
+    virtual void handle_interrupt() override;
 
     // ^CharacterDevice
     virtual const char* class_name() const override { return "SB16"; }
diff --git a/Kernel/Makefile b/Kernel/Makefile
index 7cf989c555..0838721682 100644
--- a/Kernel/Makefile
+++ b/Kernel/Makefile
@@ -15,6 +15,7 @@ OBJS = \
     Arch/i386/PIT.o \
     CMOS.o \
     Console.o \
+    Devices/HardwareEventsManager.o \
     Devices/BXVGADevice.o \
     Devices/BlockDevice.o \
     Devices/CharacterDevice.o \
@@ -54,7 +55,8 @@ OBJS = \
     FileSystem/VirtualFileSystem.o \
     Heap/SlabAllocator.o \
     Heap/kmalloc.o \
-    IRQHandler.o \
+    InterruptHandler.o \
+    SharedInterruptHandler.o \
     KBufferBuilder.o \
     KParams.o \
     KSyms.o \
@@ -74,6 +76,7 @@ OBJS = \
     PCI/IOAccess.o \
     PCI/MMIOAccess.o \
     PCI/Initializer.o \
+    PCI/Device.o \
     Process.o \
     ProcessTracer.o \
     Profiling.o \
diff --git a/Kernel/Net/E1000NetworkAdapter.cpp b/Kernel/Net/E1000NetworkAdapter.cpp
index 8ab2937fb9..9f58334498 100644
--- a/Kernel/Net/E1000NetworkAdapter.cpp
+++ b/Kernel/Net/E1000NetworkAdapter.cpp
@@ -135,24 +135,23 @@ OwnPtr<E1000NetworkAdapter> E1000NetworkAdapter::autodetect()
     return make<E1000NetworkAdapter>(found_address, irq);
 }
 
-E1000NetworkAdapter::E1000NetworkAdapter(PCI::Address pci_address, u8 irq)
-    : IRQHandler(irq)
-    , m_pci_address(pci_address)
+E1000NetworkAdapter::E1000NetworkAdapter(PCI::Address pci_address, u8 interrupt_vector)
+    : PCI::Device(pci_address, interrupt_vector)
 {
     set_interface_name("e1k");
 
     kprintf("E1000: Found at PCI address @ %w:%b:%b.%b\n", pci_address.seg(), pci_address.bus(), pci_address.slot(), pci_address.function());
 
-    enable_bus_mastering(m_pci_address);
+    enable_bus_mastering(get_pci_address());
 
     size_t mmio_base_size = PCI::get_BAR_Space_Size(pci_address, 0);
-    m_mmio_region = MM.allocate_kernel_region(PhysicalAddress(page_base_of(PCI::get_BAR0(m_pci_address))), PAGE_ROUND_UP(mmio_base_size), "E1000 MMIO", Region::Access::Read | Region::Access::Write, false, false);
+    m_mmio_region = MM.allocate_kernel_region(PhysicalAddress(page_base_of(PCI::get_BAR0(get_pci_address()))), PAGE_ROUND_UP(mmio_base_size), "E1000 MMIO", Region::Access::Read | Region::Access::Write, false, false);
     m_mmio_base = m_mmio_region->vaddr();
     m_use_mmio = true;
-    m_io_base = PCI::get_BAR1(m_pci_address) & ~1;
-    m_interrupt_line = PCI::get_interrupt_line(m_pci_address);
+    m_io_base = PCI::get_BAR1(get_pci_address()) & ~1;
+    m_interrupt_line = PCI::get_interrupt_line(get_pci_address());
     kprintf("E1000: IO port base: %w\n", m_io_base);
-    kprintf("E1000: MMIO base: P%x\n", PCI::get_BAR0(pci_address) & 0xfffffffc);
+    kprintf("E1000: MMIO base: P%x\n", PCI::get_BAR0(get_pci_address()) & 0xfffffffc);
     kprintf("E1000: MMIO base size: %u bytes\n", mmio_base_size);
     kprintf("E1000: Interrupt line: %u\n", m_interrupt_line);
     detect_eeprom();
@@ -171,14 +170,14 @@ E1000NetworkAdapter::E1000NetworkAdapter(PCI::Address pci_address, u8 irq)
     out32(REG_IMASK, 0xff & ~4);
     in32(0xc0);
 
-    enable_irq();
+    enable_interrupts();
 }
 
 E1000NetworkAdapter::~E1000NetworkAdapter()
 {
 }
 
-void E1000NetworkAdapter::handle_irq()
+void E1000NetworkAdapter::handle_interrupt()
 {
     out32(REG_IMASK, 0x1);
 
@@ -373,14 +372,14 @@ u32 E1000NetworkAdapter::in32(u16 address)
 
 void E1000NetworkAdapter::send_raw(const u8* data, int length)
 {
-    disable_irq();
+    disable_interrupts();
     u32 tx_current = in32(REG_TXDESCTAIL);
 #ifdef E1000_DEBUG
     kprintf("E1000: Sending packet (%d bytes)\n", length);
 #endif
     auto& descriptor = m_tx_descriptors[tx_current];
     ASSERT(length <= 8192);
-    auto *vptr = (void*)(descriptor.addr + 0xc0000000);
+    auto* vptr = (void*)(descriptor.addr + 0xc0000000);
     memcpy(vptr, data, length);
     descriptor.length = length;
     descriptor.status = 0;
@@ -391,7 +390,7 @@ void E1000NetworkAdapter::send_raw(const u8* data, int length)
     tx_current = (tx_current + 1) % number_of_tx_descriptors;
     out32(REG_TXDESCTAIL, tx_current);
     cli();
-    enable_irq();
+    enable_interrupts();
     for (;;) {
         if (descriptor.status) {
             sti();
diff --git a/Kernel/Net/E1000NetworkAdapter.h b/Kernel/Net/E1000NetworkAdapter.h
index 93efc84faf..fb1fbb58b9 100644
--- a/Kernel/Net/E1000NetworkAdapter.h
+++ b/Kernel/Net/E1000NetworkAdapter.h
@@ -27,23 +27,23 @@
 #pragma once
 
 #include <AK/OwnPtr.h>
-#include <Kernel/IRQHandler.h>
 #include <Kernel/Net/NetworkAdapter.h>
 #include <Kernel/PCI/Access.h>
+#include <Kernel/PCI/Device.h>
 
 class E1000NetworkAdapter final : public NetworkAdapter
-    , public IRQHandler {
+    , public PCI::Device {
 public:
     static OwnPtr<E1000NetworkAdapter> autodetect();
 
-    E1000NetworkAdapter(PCI::Address, u8 irq);
+    E1000NetworkAdapter(PCI::Address, u8 interrupt_vector);
     virtual ~E1000NetworkAdapter() override;
 
     virtual void send_raw(const u8*, int) override;
     virtual bool link_up() override;
 
 private:
-    virtual void handle_irq() override;
+    virtual void handle_interrupt() override;
     virtual const char* class_name() const override { return "E1000NetworkAdapter"; }
 
     struct [[gnu::packed]] e1000_rx_desc
@@ -86,7 +86,6 @@ private:
 
     void receive();
 
-    PCI::Address m_pci_address;
     u16 m_io_base { 0 };
     VirtualAddress m_mmio_base;
     OwnPtr<Region> m_mmio_region;
diff --git a/Kernel/Net/RTL8139NetworkAdapter.cpp b/Kernel/Net/RTL8139NetworkAdapter.cpp
index c24704f3d9..6604f5bed2 100644
--- a/Kernel/Net/RTL8139NetworkAdapter.cpp
+++ b/Kernel/Net/RTL8139NetworkAdapter.cpp
@@ -139,18 +139,17 @@ OwnPtr<RTL8139NetworkAdapter> RTL8139NetworkAdapter::autodetect()
     return make<RTL8139NetworkAdapter>(found_address, irq);
 }
 
-RTL8139NetworkAdapter::RTL8139NetworkAdapter(PCI::Address pci_address, u8 irq)
-    : IRQHandler(irq)
-    , m_pci_address(pci_address)
+RTL8139NetworkAdapter::RTL8139NetworkAdapter(PCI::Address pci_address, u8 interrupt_vector)
+    : PCI::Device(pci_address, interrupt_vector)
 {
     set_interface_name("rtl8139");
 
     kprintf("RTL8139: Found at PCI address %b:%b:%b\n", pci_address.bus(), pci_address.slot(), pci_address.function());
 
-    enable_bus_mastering(m_pci_address);
+    enable_bus_mastering(get_pci_address());
 
-    m_io_base = PCI::get_BAR0(m_pci_address) & ~1;
-    m_interrupt_line = PCI::get_interrupt_line(m_pci_address);
+    m_io_base = PCI::get_BAR0(get_pci_address()) & ~1;
+    m_interrupt_line = PCI::get_interrupt_line(get_pci_address());
     kprintf("RTL8139: IO port base: %w\n", m_io_base);
     kprintf("RTL8139: Interrupt line: %u\n", m_interrupt_line);
 
@@ -174,14 +173,14 @@ RTL8139NetworkAdapter::RTL8139NetworkAdapter(PCI::Address pci_address, u8 irq)
     const auto& mac = mac_address();
     kprintf("RTL8139: MAC address: %s\n", mac.to_string().characters());
 
-    enable_irq();
+    enable_interrupts();
 }
 
 RTL8139NetworkAdapter::~RTL8139NetworkAdapter()
 {
 }
 
-void RTL8139NetworkAdapter::handle_irq()
+void RTL8139NetworkAdapter::handle_interrupt()
 {
     for (;;) {
         int status = in16(REG_ISR);
diff --git a/Kernel/Net/RTL8139NetworkAdapter.h b/Kernel/Net/RTL8139NetworkAdapter.h
index a9d941a0fe..c998db0fb2 100644
--- a/Kernel/Net/RTL8139NetworkAdapter.h
+++ b/Kernel/Net/RTL8139NetworkAdapter.h
@@ -27,25 +27,25 @@
 #pragma once
 
 #include <AK/OwnPtr.h>
-#include <Kernel/IRQHandler.h>
 #include <Kernel/Net/NetworkAdapter.h>
 #include <Kernel/PCI/Access.h>
+#include <Kernel/PCI/Device.h>
 
 #define RTL8139_TX_BUFFER_COUNT 4
 
 class RTL8139NetworkAdapter final : public NetworkAdapter
-    , public IRQHandler {
+    , public PCI::Device {
 public:
     static OwnPtr<RTL8139NetworkAdapter> autodetect();
 
-    RTL8139NetworkAdapter(PCI::Address, u8 irq);
+    RTL8139NetworkAdapter(PCI::Address, u8 interrupt_vector);
     virtual ~RTL8139NetworkAdapter() override;
 
     virtual void send_raw(const u8*, int) override;
     virtual bool link_up() override { return m_link_up; }
 
 private:
-    virtual void handle_irq() override;
+    virtual void handle_interrupt() override;
     virtual const char* class_name() const override { return "RTL8139NetworkAdapter"; }
 
     void reset();
@@ -60,7 +60,6 @@ private:
     u16 in16(u16 address);
     u32 in32(u16 address);
 
-    PCI::Address m_pci_address;
     u16 m_io_base { 0 };
     u8 m_interrupt_line { 0 };
     u32 m_rx_buffer_addr { 0 };
diff --git a/Kernel/init.cpp b/Kernel/init.cpp
index 2f69a6e576..66ea5150dc 100644
--- a/Kernel/init.cpp
+++ b/Kernel/init.cpp
@@ -101,8 +101,14 @@ extern "C" [[noreturn]] void init()
 
     bool text_debug = KParams::the().has("text_debug");
 
+    gdt_init();
+    idt_init();
+
     setup_acpi();
 
+    // Sample test to see if the ACPI parser is working...
+    kprintf("ACPI: HPET table @ P 0x%x\n", ACPIParser::the().find_table("HPET"));
+
     new VFS;
     new DebugLogDevice;
 
@@ -114,8 +120,6 @@ extern "C" [[noreturn]] void init()
 
     RTC::initialize();
     PIC::initialize();
-    gdt_init();
-    idt_init();
 
     // call global constructors after gtd and itd init
     for (ctor_func_t* ctor = &start_ctors; ctor < &end_ctors; ctor++)
@@ -136,9 +140,6 @@ extern "C" [[noreturn]] void init()
     new VirtualConsole(1);
     VirtualConsole::switch_to(0);
 
-    // Sample test to see if the ACPI parser is working...
-    kprintf("ACPI: HPET table @ P 0x%x\n", ACPIParser::the().find_table("HPET"));
-
     PCI::Initializer::the().test_and_initialize(KParams::the().has("nopci_mmio"));
     PCI::Initializer::the().dismiss();
 
@@ -171,7 +172,6 @@ extern "C" [[noreturn]] void init()
     LoopbackAdapter::the();
     auto e1000 = E1000NetworkAdapter::autodetect();
     auto rtl8139 = RTL8139NetworkAdapter::autodetect();
-
     Process::initialize();
     Thread::initialize();
 
@@ -231,7 +231,7 @@ void init_stage2()
         hang();
     }
 
-    auto pata0 = PATAChannel::create(PATAChannel::ChannelType::Primary, force_pio);
+    auto pata0 = PATAChannel::autodetect(PATAChannel::ChannelType::Primary, force_pio);
     NonnullRefPtr<DiskDevice> root_dev = *pata0->master_device();
 
     root = root.substring(strlen("/dev/hda"), root.length() - strlen("/dev/hda"));