Merge pull request #8 from rebovas/msr

Msr + interrupts implement + crude implementation of IDT filling

2 files changed, 53 insertions, 3 deletions

diff --git a/arch/x86/idt/Idt.cpp b/arch/x86/idt/Idt.cpp
index d489f0e..cd263fb 100644
--- a/arch/x86/idt/Idt.cpp
+++ b/arch/x86/idt/Idt.cpp
@@ -69,6 +69,15 @@ DescInterrupt32 DescInterrupt32::TaskKernel(uint16 selector)
                           );
 };
 
+bool MngIdt::isIntReserved(uint8 interrupt)
+{
+    for(uint8 indx = 0; indx < reservedIntSize; indx++)
+    {
+        if(reservedInts[indx] == interrupt) return true;
+    }
+    return false;
+};
+
 MngIdt::MngIdt()
 {
     if(!isInitialize)
@@ -88,9 +97,10 @@ bool MngIdt::canDescriptorWrite(uint8 idx)
 
 bool MngIdt::addDescriptor(DescInterrupt32 desc)
 {
-    if(!canDescriptorWrite(currIdx)) return false;
+    if(!canDescriptorWrite(currIdx) or isIntReserved(currIdx)) return false;
 
-    idt[currIdx++] = desc.getDescriptor();
+    idt[currIdx] = desc.getDescriptor();
+    while(isIntReserved(++currIdx));
     return true;
 };
 
@@ -108,7 +118,7 @@ bool MngIdt::loadIdt()
 
     //Set descriptor
     uint64 descriptor = 0;
-    uint16 size = sizeof(uint64) * size - 1;
+    uint16 size = sizeof(uint64) * this->size - 1;
     uint32 offset = (uint32)(&idt);
 
     descriptor |= offset;
@@ -128,3 +138,33 @@ MngIdt &MngIdt::getInstance()
     if(!isInitialize) mngIdt = MngIdt();
     return mngIdt;
 };
+
+void DescInterrupt32::setOffset(uint32 offset)
+{
+    uint8 gateType = attributes & 0x0f;
+
+    if(!(gateType == TSK_GATE and offset != 0))
+    {
+        offsetLow = offset & 0xffff;
+        offsetHight = (offset & 0xffff0000) >> 16;
+    }
+};
+void DescInterrupt32::setGateType(uint8 gateType)
+{
+    if(gateType < TSK_GATE
+        or (gateType > TRAP_GATE_16 and gateType < INT_GATE_32)
+        or gateType > TRAP_GATE_32
+    ) return;
+    else if(gateType == TSK_GATE)
+    {
+        offsetLow = offsetHight = 0;
+    }
+
+    attributes &= 0xfff0;
+    attributes |= (gateType & 0x0f);
+};
+
+void DescInterrupt32::setDpl(uint8 dpl)
+{
+    attributes = (dpl & 0x03) << 5;
+};
diff --git a/arch/x86/idt/Idt.h b/arch/x86/idt/Idt.h
index c90b674..7370526 100644
--- a/arch/x86/idt/Idt.h
+++ b/arch/x86/idt/Idt.h
@@ -32,6 +32,9 @@ class DescInterrupt32
         DescInterrupt32() = default;
         DescInterrupt32(const DescInterrupt32 &) = default; 
         DescInterrupt32(uint32 offset, uint16 selector, uint8 attr);
+        void setOffset(uint32 offset);
+        void setGateType(uint8 gateType);
+        void setDpl(uint8 dpl);
         uint64 getDescriptor();
         static DescInterrupt32 InterruptKernelLong(uint32 offset, 
                                                     uint16 selector);
@@ -43,6 +46,13 @@ class DescInterrupt32
 class MngIdt
 {
     private:
+        const static uint8 reservedIntSize = 12;
+        constexpr static uint8 reservedInts[reservedIntSize] = 
+        {
+            9, 15, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31
+        };
+        // If false interrupt number isn't reserved, true - reserved
+        bool isIntReserved(uint8 interrupt);
         const static uint8 size = 255;
         static uint64 idt[size];
         static bool isInitialize;