X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86%2Fmm_virt.c;h=e2442ae10be60667897bb74ab726bbe527539712;hb=c5de7b08d4a82908a5acf6454fd7836bdab68715;hp=82f8f970f23df1ff726a41379e7dbff90fc94dc8;hpb=1efe16513589743037b602f2d388b4dcc73f0b0b;p=tpg%2Facess2.git

diff --git a/Kernel/arch/x86/mm_virt.c b/Kernel/arch/x86/mm_virt.c
index 82f8f970..e2442ae1 100644
--- 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