Kernel/x86 - Fix PMem bitmap overflow

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

diff --git a/KernelLand/Kernel/arch/x86/mm_virt.c b/KernelLand/Kernel/arch/x86/mm_virt.c
index b81698c..a623974 100644 (file)
--- a/KernelLand/Kernel/arch/x86/mm_virt.c
+++ b/KernelLand/Kernel/arch/x86/mm_virt.c
@@ -129,10 +129,8 @@ void MM_PreinitVirtual(void)
  */
 void MM_InstallVirtual(void)
 {
-        int    i;
-       
        // --- Pre-Allocate kernel tables
-       for( i = KERNEL_BASE>>22; i < 1024; i ++ )
+       for( int i = KERNEL_BASE>>22; i < 1024; i ++ )
        {
                if( gaPageDir[ i ] )    continue;
                // Skip stack tables, they are process unique
@@ -147,7 +145,7 @@ void MM_InstallVirtual(void)
        }
        
        // Unset kernel on the User Text pages
-       for( i = ((tVAddr)&_UsertextEnd-(tVAddr)&_UsertextBase+0xFFF)/4096; i--; ) {
+       for( int i = ((tVAddr)&_UsertextEnd-(tVAddr)&_UsertextBase+0xFFF)/4096; i--; ) {
                MM_SetFlags( (tVAddr)&_UsertextBase + i*4096, 0, MM_PFLAG_KERNEL );
        }
        
@@ -753,10 +751,10 @@ tVAddr MM_NewKStack(void)
  */
 tVAddr MM_NewWorkerStack(Uint *StackContents, size_t ContentsSize)
 {
-       Uint    base, addr;
-       tVAddr  tmpPage;
+       Uint    base;
        tPAddr  page;
        
+       LOG("(StackContents=%p,ContentsSize=%i)", StackContents, ContentsSize);
        // TODO: Thread safety
        // Find a free worker stack address
        for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
@@ -774,9 +772,10 @@ tVAddr MM_NewWorkerStack(Uint *StackContents, size_t ContentsSize)
                break;
        }
        if(base >= NUM_WORKER_STACKS) {
-               Warning("Uh-oh! Out of worker stacks");
+               Log_Error("MMVirt", "Uh-oh! Out of worker stacks");
                return 0;
        }
+       LOG("base=0x%x", base);
        
        // It's ours now!
        gWorkerStacks[base/32] |= (1 << base);
@@ -785,6 +784,7 @@ tVAddr MM_NewWorkerStack(Uint *StackContents, size_t ContentsSize)
        // We have one
        base = WORKER_STACKS + base * WORKER_STACK_SIZE;
        //Log(" MM_NewWorkerStack: base = 0x%x", base);
+       LOG("base=%p (top)", base);
        
        // Set the temp fractals to TID0's address space
        GET_TEMP_MAPPING( ((Uint)gaInitPageDir - KERNEL_BASE) );
@@ -792,29 +792,33 @@ tVAddr MM_NewWorkerStack(Uint *StackContents, size_t ContentsSize)
        
        // Check if the directory is mapped (we are assuming that the stacks
        // will fit neatly in a directory)
-       //Log(" MM_NewWorkerStack: gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
+       LOG("gaTmpDir[ 0x%x ] = 0x%x", base>>22, gaTmpDir[ base >> 22 ]);
        if(gaTmpDir[ base >> 22 ] == 0) {
                gaTmpDir[ base >> 22 ] = MM_AllocPhys() | 3;
                INVLPG( &gaTmpTable[ (base>>12) & ~0x3FF ] );
        }
        
        // Mapping Time!
-       for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
+       for( Uint addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
        {
                page = MM_AllocPhys();
                gaTmpTable[ (base + addr) >> 12 ] = page | 3;
        }
+       LOG("mapped");
 
        // Release temporary fractal
        REL_TEMP_MAPPING();
 
        // NOTE: Max of 1 page
        // `page` is the last allocated page from the previious for loop
-       tmpPage = (tVAddr)MM_MapTemp( page );
-       memcpy( (void*)( tmpPage + (0x1000 - ContentsSize) ), StackContents, ContentsSize);
-       MM_FreeTemp( (void*)tmpPage );
+       LOG("Mapping first page");
+       char    *tmpPage = MM_MapTemp( page );
+       LOG("tmpPage=%p", tmpPage);
+       memcpy( tmpPage + (0x1000 - ContentsSize), StackContents, ContentsSize);
+       MM_FreeTemp( tmpPage );
        
        //Log("MM_NewWorkerStack: RETURN 0x%x", base);
+       LOG("return %p", base+WORKER_STACK_SIZE);
        return base + WORKER_STACK_SIZE;
 }
 
@@ -982,25 +986,26 @@ tPAddr MM_DuplicatePage(tVAddr VAddr)
  * \brief Create a temporary memory mapping
  * \todo Show Luigi Barone (C Lecturer) and see what he thinks
  */
-void * MM_MapTemp(tPAddr PAddr)
+void *MM_MapTemp(tPAddr PAddr)
 {
-       //ENTER("XPAddr", PAddr);
+       ENTER("PPAddr", PAddr);
        
        PAddr &= ~0xFFF;
        
-       //LOG("glTempMappings = %i", glTempMappings);
-       
        if( Semaphore_Wait(&gTempMappingsSem, 1) != 1 )
                return NULL;
+       LOG("Semaphore good");
        Mutex_Acquire( &glTempMappings );
        for( int i = 0; i < NUM_TEMP_PAGES; i ++ )
        {
+               Uint32  *pte = &gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ];
+               LOG("%i: %x", i, *pte);
                // Check if page used
-               if(gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] & 1)        continue;
+               if(*pte & 1)    continue;
                // Mark as used
-               gaPageTable[ (TEMP_MAP_ADDR >> 12) + i ] = PAddr | 3;
+               *pte = PAddr | 3;
                INVLPG( TEMP_MAP_ADDR + (i << 12) );
-               //LEAVE('p', TEMP_MAP_ADDR + (i << 12));
+               LEAVE('p', TEMP_MAP_ADDR + (i << 12));
                Mutex_Release( &glTempMappings );
                return (void*)( TEMP_MAP_ADDR + (i << 12) );
        }