From 6a691306b56ec58b2c77859e124446546f82f04a Mon Sep 17 00:00:00 2001
From: Liav A <liavalb@gmail.com>
Date: Sat, 19 Dec 2020 13:56:12 +0200
Subject: [PATCH] Kernel: Add a method to gather the devices count of a Storage
 controller

Also, change device() method to be const.
---
 Kernel/Storage/IDEChannel.cpp      |  4 ++--
 Kernel/Storage/IDEChannel.h        |  4 ++--
 Kernel/Storage/IDEController.cpp   | 12 +++++++++++-
 Kernel/Storage/IDEController.h     |  3 ++-
 Kernel/Storage/StorageController.h |  3 ++-
 5 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/Kernel/Storage/IDEChannel.cpp b/Kernel/Storage/IDEChannel.cpp
index 0bb1e41e349..6334605c2c9 100644
--- a/Kernel/Storage/IDEChannel.cpp
+++ b/Kernel/Storage/IDEChannel.cpp
@@ -114,11 +114,11 @@ NonnullOwnPtr<IDEChannel> IDEChannel::create(const IDEController& controller, IO
     return make<IDEChannel>(controller, io_group, type, force_pio);
 }
 
-RefPtr<StorageDevice> IDEChannel::master_device()
+RefPtr<StorageDevice> IDEChannel::master_device() const
 {
     return m_master;
 }
-RefPtr<StorageDevice> IDEChannel::slave_device()
+RefPtr<StorageDevice> IDEChannel::slave_device() const
 {
     return m_slave;
 }
diff --git a/Kernel/Storage/IDEChannel.h b/Kernel/Storage/IDEChannel.h
index ae2cfea5f32..d138a18bbac 100644
--- a/Kernel/Storage/IDEChannel.h
+++ b/Kernel/Storage/IDEChannel.h
@@ -108,8 +108,8 @@ public:
     IDEChannel(const IDEController&, IOAddressGroup, ChannelType type, bool force_pio);
     virtual ~IDEChannel() override;
 
-    RefPtr<StorageDevice> master_device();
-    RefPtr<StorageDevice> slave_device();
+    RefPtr<StorageDevice> master_device() const;
+    RefPtr<StorageDevice> slave_device() const;
 
     virtual const char* purpose() const override { return "PATA Channel"; }
 
diff --git a/Kernel/Storage/IDEController.cpp b/Kernel/Storage/IDEController.cpp
index 00e89284ce4..0d64d8d331e 100644
--- a/Kernel/Storage/IDEController.cpp
+++ b/Kernel/Storage/IDEController.cpp
@@ -47,6 +47,16 @@ bool IDEController::shutdown()
     TODO();
 }
 
+size_t IDEController::devices_count() const
+{
+    size_t count = 0;
+    for (u32 index = 0; index < 4; index++) {
+        if (!device(index).is_null())
+            count++;
+    }
+    return count;
+}
+
 void IDEController::start_request(const StorageDevice&, AsyncBlockDeviceRequest&)
 {
     ASSERT_NOT_REACHED();
@@ -85,7 +95,7 @@ void IDEController::initialize(bool force_pio)
     m_channels.append(IDEChannel::create(*this, { base_io, control_io, bus_master_base.offset(8) }, IDEChannel::ChannelType::Secondary, force_pio));
 }
 
-RefPtr<StorageDevice> IDEController::device(u32 index)
+RefPtr<StorageDevice> IDEController::device(u32 index) const
 {
     switch (index) {
     case 0:
diff --git a/Kernel/Storage/IDEController.h b/Kernel/Storage/IDEController.h
index 40ab04886a4..402d1a44e32 100644
--- a/Kernel/Storage/IDEController.h
+++ b/Kernel/Storage/IDEController.h
@@ -45,9 +45,10 @@ public:
     virtual ~IDEController() override;
 
     virtual Type type() const override { return Type::IDE; }
-    virtual RefPtr<StorageDevice> device(u32 index) override;
+    virtual RefPtr<StorageDevice> device(u32 index) const override;
     virtual bool reset() override;
     virtual bool shutdown() override;
+    virtual size_t devices_count() const override;
     virtual void start_request(const StorageDevice&, AsyncBlockDeviceRequest&) override;
     virtual void complete_current_request(AsyncDeviceRequest::RequestResult) override;
 
diff --git a/Kernel/Storage/StorageController.h b/Kernel/Storage/StorageController.h
index 6dba3f21fea..d01a3374a45 100644
--- a/Kernel/Storage/StorageController.h
+++ b/Kernel/Storage/StorageController.h
@@ -51,7 +51,8 @@ public:
         NVMe
     };
     virtual Type type() const = 0;
-    virtual RefPtr<StorageDevice> device(u32 index) = 0;
+    virtual RefPtr<StorageDevice> device(u32 index) const = 0;
+    virtual size_t devices_count() const = 0;
 
 protected:
     explicit StorageController(PCI::Address address)