Bugfixing a hidden bug in vm8086 (to help trace a tcp bug)

[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 dce4782..8c59ea0 100644 (file)
--- a/Kernel/arch/x86/mm_virt.c
+++ b/Kernel/arch/x86/mm_virt.c
@@ -55,8 +55,9 @@
 #define        PF_PRESENT      0x1
 #define        PF_WRITE        0x2
 #define        PF_USER         0x4
+#define PF_GLOBAL      0x80
 #define        PF_COW          0x200
-#define        PF_PAGED        0x400
+#define        PF_NOPAGE       0x400
 
 #define INVLPG(addr)   __asm__ __volatile__ ("invlpg (%0)"::"r"(addr))
 
@@ -78,6 +79,7 @@ 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);
 tPAddr MM_DuplicatePage(tVAddr VAddr);
 
 // === GLOBALS ===
@@ -217,6 +219,9 @@ void MM_PageFault(tVAddr Addr, Uint ErrorCode, tRegs *Regs)
                        );
                Warning("User Pagefault: Instruction at %04x:%08x accessed %p", Regs->cs, Regs->eip, Addr);
                __asm__ __volatile__ ("sti");   // Restart IRQs
+               #if 1
+               Error_Backtrace(Regs->eip, Regs->ebp);
+               #endif
                Threads_SegFault(Addr);
                return ;
        }
@@ -272,7 +277,7 @@ void MM_DumpTables(tVAddr Start, tVAddr End)
        tPAddr  expected = 0;
        tVAddr  curPos;
        Uint    page;
-       const tPAddr    MASK = ~0xF98;
+       const tPAddr    MASK = ~0xF78;
        
        Start >>= 12;   End >>= 12;
        
@@ -302,14 +307,16 @@ void MM_DumpTables(tVAddr Start, tVAddr End)
                ||  (gaPageTable[page] & MASK) != expected)
                {
                        if(expected) {
-                               Log(" 0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
-                                       rangeStart, curPos - 1,
+                               Log(" 0x%08x => 0x%08x - 0x%08x (%s%s%s%s%s)",
+                                       rangeStart,
                                        gaPageTable[rangeStart>>12] & ~0xFFF,
-                                       (expected & ~0xFFF) - 1,
-                                       (expected & PF_PAGED ? "p" : "-"),
+                                       curPos - rangeStart,
+                                       (expected & PF_NOPAGE ? "P" : "-"),
                                        (expected & PF_COW ? "C" : "-"),
+                                       (expected & PF_GLOBAL ? "G" : "-"),
                                        (expected & PF_USER ? "U" : "-"),
-                                       (expected & PF_WRITE ? "W" : "-")
+                                       (expected & PF_WRITE ? "W" : "-"),
+                                       gaPageTable[page] & MASK, expected
                                        );
                                expected = 0;
                        }
@@ -323,11 +330,11 @@ void MM_DumpTables(tVAddr Start, tVAddr End)
        }
        
        if(expected) {
-               Log("0x%08x-0x%08x => 0x%08x-0x%08x (%s%s%s%s)",
-                       rangeStart, curPos - 1,
+               Log("0x%08x => 0x%08x - 0x%08x (%s%s%s%s)",
+                       rangeStart,
                        gaPageTable[rangeStart>>12] & ~0xFFF,
-                       (expected & ~0xFFF) - 1,
-                       (expected & PF_PAGED ? "p" : "-"),
+                       curPos - rangeStart,
+                       (expected & PF_NOPAGE ? "p" : "-"),
                        (expected & PF_COW ? "C" : "-"),
                        (expected & PF_USER ? "U" : "-"),
                        (expected & PF_WRITE ? "W" : "-")
@@ -541,37 +548,40 @@ tPAddr MM_Clone(void)
        //LOG("Allocated Directory (%x)", *gpTmpCR3);
        memsetd( gaTmpDir, 0, 1024 );
        
-       // Copy Tables
-       for( i = 0; i < 768; i ++)
-       {
-               // Check if table is allocated
-               if( !(gaPageDir[i] & PF_PRESENT) ) {
-                       gaTmpDir[i] = 0;
-                       page += 1024;
-                       continue;
-               }
-               
-               // Allocate new table
-               gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
-               INVLPG( &gaTmpTable[page] );
-               // Fill
-               for( j = 0; j < 1024; j ++, page++ )
+       if( Threads_GetPID() != 0 )
+       {       
+               // Copy Tables
+               for( i = 0; i < 768; i ++)
                {
-                       if( !(gaPageTable[page] & PF_PRESENT) ) {
-                               gaTmpTable[page] = 0;
+                       // Check if table is allocated
+                       if( !(gaPageDir[i] & PF_PRESENT) ) {
+                               gaTmpDir[i] = 0;
+                               page += 1024;
                                continue;
                        }
                        
-                       // Refrence old page
-                       MM_RefPhys( gaPageTable[page] & ~0xFFF );
-                       // Add to new table
-                       if(gaPageTable[page] & PF_WRITE) {
-                               gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
-                               gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
-                               INVLPG( page << 12 );
+                       // Allocate new table
+                       gaTmpDir[i] = MM_AllocPhys() | (gaPageDir[i] & 7);
+                       INVLPG( &gaTmpTable[page] );
+                       // Fill
+                       for( j = 0; j < 1024; j ++, page++ )
+                       {
+                               if( !(gaPageTable[page] & PF_PRESENT) ) {
+                                       gaTmpTable[page] = 0;
+                                       continue;
+                               }
+                               
+                               // Refrence old page
+                               MM_RefPhys( gaPageTable[page] & ~0xFFF );
+                               // Add to new table
+                               if(gaPageTable[page] & PF_WRITE) {
+                                       gaTmpTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
+                                       gaPageTable[page] = (gaPageTable[page] & ~PF_WRITE) | PF_COW;
+                                       INVLPG( page << 12 );
+                               }
+                               else
+                                       gaTmpTable[page] = gaPageTable[page];
                        }
-                       else
-                               gaTmpTable[page] = gaPageTable[page];
                }
        }
        
@@ -653,17 +663,32 @@ tPAddr MM_Clone(void)
  */
 tVAddr MM_NewKStack(void)
 {
-       tVAddr  base = KERNEL_STACKS;
+       tVAddr  base;
        Uint    i;
-       for(;base<KERNEL_STACKS_END;base+=KERNEL_STACK_SIZE)
+       for(base = KERNEL_STACKS; base < KERNEL_STACKS_END; base += KERNEL_STACK_SIZE)
        {
+               // Check if space is free
                if(MM_GetPhysAddr(base) != 0)   continue;
-               for(i=0;i<KERNEL_STACK_SIZE;i+=0x1000) {
-                       MM_Allocate(base+i);
+               // Allocate
+               //for(i = KERNEL_STACK_SIZE; i -= 0x1000 ; )
+               for(i = 0; i < KERNEL_STACK_SIZE; i += 0x1000 )
+               {
+                       if( MM_Allocate(base+i) == 0 )
+                       {
+                               // On error, print a warning and return error
+                               Warning("MM_NewKStack - Out of memory");
+                               // - Clean up
+                               //for( i += 0x1000 ; i < KERNEL_STACK_SIZE; i += 0x1000 )
+                               //      MM_Deallocate(base+i);
+                               return 0;
+                       }
                }
+               // Success
+               Log("MM_NewKStack - Allocated %p", base + KERNEL_STACK_SIZE);
                return base+KERNEL_STACK_SIZE;
        }
-       Warning("MM_NewKStack - No address space left\n");
+       // No stacks left
+       Warning("MM_NewKStack - No address space left");
        return 0;
 }
 
@@ -684,6 +709,7 @@ tVAddr MM_NewWorkerStack()
        __asm__ __volatile__ ("mov %%esp, %0": "=r"(esp));
        __asm__ __volatile__ ("mov %%ebp, %0": "=r"(ebp));
        
+       // TODO: Thread safety
        // Find a free worker stack address
        for(base = giLastUsedWorker; base < NUM_WORKER_STACKS; base++)
        {
@@ -731,6 +757,7 @@ tVAddr MM_NewWorkerStack()
        
        // Mapping Time!
        for( addr = 0; addr < WORKER_STACK_SIZE; addr += 0x1000 )
+       //for( addr = WORKER_STACK_SIZE; addr; addr -= 0x1000 )
        {
                pages[ addr >> 12 ] = MM_AllocPhys();
                gaTmpTable[ (base + addr) >> 12 ] = pages[addr>>12] | 3;
@@ -918,7 +945,7 @@ tVAddr MM_MapTemp(tPAddr PAddr)
                        return TEMP_MAP_ADDR + (i << 12);
                }
                Mutex_Release( &glTempMappings );
-               Threads_Yield();        // TODO: Less expensive
+               Threads_Yield();        // TODO: Use a sleep queue here instead
        }
 }