Kernel/x86 - Fixed timing error that caused time to increment at 2x real speed

[tpg/acess2.git] / Kernel / arch / x86 / mm_virt.c

diff --git a/Kernel/arch/x86/mm_virt.c b/Kernel/arch/x86/mm_virt.c
index 82f8f97..e2442ae 100644 (file)
--- a/Kernel/arch/x86/mm_virt.c
+++ b/Kernel/arch/x86/mm_virt.c
@@ -15,6 +15,7 @@
 #include <mm_virt.h>
 #include <mm_phys.h>
 #include <proc.h>
+#include <hal_proc.h>
 
 #define TAB    22
 
@@ -69,8 +70,8 @@ extern void   Error_Backtrace(Uint eip, Uint ebp);
 void   MM_PreinitVirtual(void);
 void   MM_InstallVirtual(void);
 void   MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs);
-void   MM_DumpTables(tVAddr Start, tVAddr End);
-tVAddr MM_ClearUser(void);
+//void MM_DumpTables(tVAddr Start, tVAddr End);
+//void MM_ClearUser(void);
 tPAddr MM_DuplicatePage(tVAddr VAddr);
 
 // === GLOBALS ===
@@ -475,10 +476,9 @@ int MM_Map(tVAddr VAddr, tPAddr PAddr)
 }
 
 /**
- * \fn tVAddr MM_ClearUser()
  * \brief Clear user's address space
  */
-tVAddr MM_ClearUser(void)
+void MM_ClearUser(void)
 {
        Uint    i, j;
        
@@ -504,8 +504,6 @@ tVAddr MM_ClearUser(void)
                INVLPG( &gaPageTable[i*1024] );
        }
        INVLPG( gaPageDir );
-       
-       return *gpPageCR3;
 }
 
 /**
@@ -829,6 +827,45 @@ Uint MM_GetFlags(tVAddr VAddr)
        return ret;
 }
 
+/**
+ * \brief Check if the provided buffer is valid
+ * \return Boolean valid
+ */
+int MM_IsValidBuffer(tVAddr Addr, size_t Size)
+{
+        int    bIsUser;
+        int    dir, tab;
+
+       Size += Addr & (PAGE_SIZE-1);
+       Addr &= ~(PAGE_SIZE-1);
+
+       dir = Addr >> 22;
+       tab = Addr >> 12;
+       
+//     Debug("Addr = %p, Size = 0x%x, dir = %i, tab = %i", Addr, Size, dir, tab);
+
+       if( !(gaPageDir[dir] & 1) )     return 0;
+       if( !(gaPageTable[tab] & 1) )   return 0;
+       
+       bIsUser = !!(gaPageTable[tab] & PF_USER);
+
+       while( Size >= PAGE_SIZE )
+       {
+               if( (tab & 1023) == 0 )
+               {
+                       dir ++;
+                       if( !(gaPageDir[dir] & 1) )     return 0;
+               }
+               
+               if( !(gaPageTable[tab] & 1) )   return 0;
+               if( bIsUser && !(gaPageTable[tab] & PF_USER) )  return 0;
+
+               tab ++;
+               Size -= PAGE_SIZE;
+       }
+       return 1;
+}
+
 /**
  * \fn tPAddr MM_DuplicatePage(tVAddr VAddr)
  * \brief Duplicates a virtual page to a physical one