Migrate KE subsystem to C++

xtoskrnl/ke/sysres.cc

@@ -0,0 +1,238 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            xtoskrnl/ke/sysres.cc
+ * DESCRIPTION:     System resources management; This code is based on the MinocaOS implementation
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#include <xtos.hh>
+
+
+/* Kernel Library */
+namespace KE
+{
+
+/**
+ * Looks for an unacquired system resource of the specified type and acquires it.
+ *
+ * @param ResourceType
+ *        Supplies system resource type.
+ *
+ * @param ResourceHeader
+ *        Specifies a memory area where a pointer to the system resource header will be stored.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+XTSTATUS
+SystemResources::AcquireResource(IN SYSTEM_RESOURCE_TYPE ResourceType,
+                                 OUT PSYSTEM_RESOURCE_HEADER *ResourceHeader)
+{
+    /* Get system resource and acquire an ownership */
+    return GetSystemResource(ResourceType, TRUE, ResourceHeader);
+}
+
+/**
+ * Looks for an unacquired system resource of the specified type.
+ *
+ * @param ResourceType
+ *        Supplies system resource type.
+ *
+ * @param Acquire
+ *        Specifies whether system resource should be acquired or not.
+ *
+ * @param ResourceHeader
+ *        Specifies a memory area where a pointer to the system resource header will be stored.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+XTSTATUS
+SystemResources::GetSystemResource(IN SYSTEM_RESOURCE_TYPE ResourceType,
+                                   IN BOOLEAN ResourceLock,
+                                   OUT PSYSTEM_RESOURCE_HEADER *ResourceHeader)
+{
+    PSYSTEM_RESOURCE_HEADER Resource;
+    PLIST_ENTRY ListEntry;
+    BOOLEAN Interrupts;
+    XTSTATUS Status;
+
+    /* Assume resource found successfully */
+    Status = STATUS_SUCCESS;
+
+    /* Check if interrupts are enabled */
+    Interrupts = AR::CpuFunc::InterruptsEnabled();
+
+    /* Disable interrupts and acquire a spinlock */
+    AR::CpuFunc::ClearInterruptFlag();
+    SpinLock::AcquireSpinLock(&ResourcesLock);
+
+    /* Iterate through system resources list */
+    ListEntry = ResourcesListHead.Flink;
+    while(ListEntry != &ResourcesListHead)
+    {
+        /* Get resource header */
+        Resource = CONTAIN_RECORD(ListEntry, SYSTEM_RESOURCE_HEADER, ListEntry);
+
+        /* Check if resource type matches */
+        if(Resource->ResourceType == ResourceType)
+        {
+            /* Check if resource is locked */
+            if(Resource->ResourceLocked)
+            {
+                /* Resource locked, set status code and stop browsing a list */
+                Status = STATUS_RESOURCE_LOCKED;
+                break;
+            }
+
+            /* Check if resource lock should be acquired */
+            if(ResourceLock)
+            {
+                /* Acquire resource lock */
+                Resource->ResourceLocked = TRUE;
+            }
+
+            /* Stop browsing a list */
+            break;
+        }
+
+        /* Go to the next list entry */
+        ListEntry = ListEntry->Flink;
+    }
+
+    /* Check if resource was found */
+    if(ListEntry == &ResourcesListHead)
+    {
+        /* Resource not found, return NULL */
+        Resource = nullptr;
+        Status = STATUS_NOT_FOUND;
+    }
+
+    /* Release spinlock and re-enable interrupts if necessary */
+    SpinLock::ReleaseSpinLock(&ResourcesLock);
+    if(Interrupts)
+    {
+        /* Re-enable interrupts */
+        AR::CpuFunc::SetInterruptFlag();
+    }
+
+    /* Return resource header and status code */
+    *ResourceHeader = Resource;
+    return Status;
+}
+
+/**
+ * Looks for an unacquired system resource of the specified type and returns it without acquiring an ownership.
+ *
+ * @param ResourceType
+ *        Supplies system resource type.
+ *
+ * @param ResourceHeader
+ *        Specifies a memory area where a pointer to the system resource header will be stored.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+XTSTATUS
+SystemResources::GetResource(IN SYSTEM_RESOURCE_TYPE ResourceType,
+                             OUT PSYSTEM_RESOURCE_HEADER *ResourceHeader)
+{
+    /* Get system resource without acquiring an ownership */
+    return GetSystemResource(ResourceType, FALSE, ResourceHeader);
+}
+
+/**
+ * Initializes system resource management.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+SystemResources::InitializeResources(VOID)
+{
+    PSYSTEM_RESOURCE_HEADER ResourceHeader;
+    PLIST_ENTRY ListEntry, NextListEntry;
+    ULONG ResourceSize;
+
+    /* Initialize system resources spin lock and resource list */
+    SpinLock::InitializeSpinLock(&ResourcesLock);
+    RtlInitializeListHead(&ResourcesListHead);
+
+    /* Make sure there are some system resources available */
+    if(!RtlListEmpty(BootInformation::GetSystemResources()))
+    {
+        /* Iterate through system resources list */
+        ListEntry = BootInformation::GetSystemResources()->Flink;
+        while(ListEntry != BootInformation::GetSystemResources())
+        {
+            /* Get resource header and next list entry */
+            ResourceHeader = CONTAIN_RECORD(ListEntry, SYSTEM_RESOURCE_HEADER, ListEntry);
+            NextListEntry = ListEntry->Flink;
+
+            /* Basic resource type validation */
+            switch(ResourceHeader->ResourceType)
+            {
+                case SystemResourceAcpi:
+                    /* ACPI system resource */
+                    ResourceSize = sizeof(SYSTEM_RESOURCE_ACPI);
+                    break;
+                case SystemResourceFrameBuffer:
+                    /* FrameBuffer system resource */
+                    ResourceSize = sizeof(SYSTEM_RESOURCE_FRAMEBUFFER);
+                    break;
+                default:
+                    /* Unknown system resource type, skip it */
+                    ResourceSize = 0;
+                    break;
+            }
+
+            /* Validate resource size */
+            if(ResourceSize != 0 && ResourceSize == ResourceHeader->ResourceSize)
+            {
+                /* Move valid resource to the internal kernel list of system resources */
+                RtlRemoveEntryList(&ResourceHeader->ListEntry);
+                RtlInsertTailList(&ResourcesListHead, &ResourceHeader->ListEntry);
+            }
+
+            /* Go to the next list entry */
+            ListEntry = NextListEntry;
+        }
+    }
+}
+
+/**
+ * Releases boot system resource.
+ *
+ * @param ResourceHeader
+ *        Specifies a pointer to the boot system resource header.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+SystemResources::ReleaseResource(IN PSYSTEM_RESOURCE_HEADER ResourceHeader)
+{
+    /* Disable interrupts and acquire a spinlock */
+    AR::CpuFunc::ClearInterruptFlag();
+    SpinLock::AcquireSpinLock(&ResourcesLock);
+
+    /* Release resource lock */
+    ResourceHeader->ResourceLocked = FALSE;
+
+    /* Release spinlock and enable interrupts */
+    SpinLock::ReleaseSpinLock(&ResourcesLock);
+    AR::CpuFunc::SetInterruptFlag();
+}
+
+} /* namespace */