Kernel/x86_64 - Fixed Kernel not using COW, cleanup

- Didn't have the WP bit set, meaning the kernel wasn't
  using the PT.W bit, hence COW didn't work if the kernel changed
  the page.
- Cleaned up all the x86_64 debug code

diff --git a/Kernel/arch/x86/include/proc.h b/Kernel/arch/x86/include/proc.h
index e449a0f..73bddbb 100644 (file)
--- a/Kernel/arch/x86/include/proc.h
+++ b/Kernel/arch/x86/include/proc.h
@@ -23,4 +23,6 @@ typedef struct sTSS {
        Uint16  Resvd, IOPB;    // IO Permissions Bitmap
 } __attribute__((packed)) tTSS;
 
+#define USER_MAX       KERNEL_BASE
+
 #endif

diff --git a/Kernel/arch/x86/start.asm b/Kernel/arch/x86/start.asm
index 8c7d9a6..d504a5d 100644 (file)
--- a/Kernel/arch/x86/start.asm
+++ b/Kernel/arch/x86/start.asm
@@ -70,7 +70,7 @@ start:
        mov cr3, ecx
        
        mov ecx, cr0
-       or      ecx, 0x80010000 ; PG and WP
+       or ecx, 0x80010000      ; PG and WP
        mov cr0, ecx
        
        mov WORD [0xB8002], 0x0763      ; 'c'

diff --git a/Kernel/arch/x86_64/main.c b/Kernel/arch/x86_64/main.c
index d3b79c6..c154870 100644 (file)
--- a/Kernel/arch/x86_64/main.c
+++ b/Kernel/arch/x86_64/main.c
@@ -41,8 +41,6 @@ void kmain(Uint MbMagic, void *MbInfoPtr)
                // Adjust Multiboot structure address
                mbInfo = (void*)( (Uint)MbInfoPtr + KERNEL_BASE );
                gsBootCmdLine = (char*)( (Uint)mbInfo->CommandLine + KERNEL_BASE);
-               Log("gsBootCmdLine = '%s'", gsBootCmdLine);
-               
                MM_InitPhys_Multiboot( mbInfo );        // Set up physical memory manager
                break;
        default:
@@ -57,14 +55,13 @@ void kmain(Uint MbMagic, void *MbInfoPtr)
        Heap_Install();
        
        *(Uint16*)(KERNEL_BASE|0xB8000) = 0x1F00|'E';
-       Log_Log("Arch", "Starting threading...");
        Threads_Init();
        
        Time_Setup();
        *(Uint16*)(KERNEL_BASE|0xB8000) = 0x1F00|'F';
        
-       Log_Log("Arch", "Starting VFS...");
        // Load Virtual Filesystem
+       Log_Log("Arch", "Starting VFS...");
        VFS_Init();
        
        *(Uint16*)(KERNEL_BASE|0xB8000) = 0x1F00|'Z';

diff --git a/Kernel/arch/x86_64/mm_phys.c b/Kernel/arch/x86_64/mm_phys.c
index 064622f..c2c215b 100644 (file)
--- a/Kernel/arch/x86_64/mm_phys.c
+++ b/Kernel/arch/x86_64/mm_phys.c
@@ -183,7 +183,7 @@ void MM_InitPhys_Multiboot(tMBoot_Info *MBoot)
                                paddr = ent->Base;
                        }
                        
-                       Log(" MM_InitPhys_Multiboot: paddr=0x%x, avail=%i", paddr, avail);
+                       Log("MM_InitPhys_Multiboot: paddr=0x%x, avail=0x%x pg", paddr, avail);
                        
                        // Map
                        while( todo && avail --)
@@ -509,7 +509,7 @@ void MM_RefPhys(tPAddr PAddr)
                                return ;
                        }
                        // Fill block
-                       Log("Allocated references for %P-%P", page_base << 12, (page_base+pages_per_refpage-1)<<12);
+                       Log("Allocated references for %P-%P", page_base << 12, (page_base+pages_per_refpage)<<12);
                        for( i = 0; i < pages_per_refpage; i ++ ) {
                                 int    pg = page_base + i;
                                gaiPageReferences[pg] = !!PAGE_ALLOC_TEST(pg);

diff --git a/Kernel/arch/x86_64/mm_virt.c b/Kernel/arch/x86_64/mm_virt.c
index 1bb890c..12bb3a4 100644 (file)
--- a/Kernel/arch/x86_64/mm_virt.c
+++ b/Kernel/arch/x86_64/mm_virt.c
@@ -80,7 +80,7 @@ tPAddr        gMM_ZeroPage;
 // === CODE ===
 void MM_InitVirt(void)
 {
-       Log_Debug("MMVirt", "&PAGEMAPLVL4(0) = %p", &PAGEMAPLVL4(0));
+//     Log_Debug("MMVirt", "&PAGEMAPLVL4(0) = %p", &PAGEMAPLVL4(0));
 //     MM_DumpTables(0, -1L);
 }
 
@@ -106,6 +106,7 @@ void MM_int_ClonePageEnt( Uint64 *Ent, void *NextLevel, tVAddr Addr, int bTable
        {
                *Ent &= ~PF_COW;
                *Ent |= PF_PRESENT|PF_WRITE;
+//             Log_Debug("MMVirt", "COW ent at %p (%p) only %P", Ent, NextLevel, curpage);
        }
        else
        {
@@ -820,18 +821,21 @@ tPAddr MM_Clone(void)
                if( TMPMAPLVL4(i) & 1 )
                        MM_RefPhys( TMPMAPLVL4(i) & PADDR_MASK );
        }
+
+       // Mark Per-Process data as COW
+       TMPMAPLVL4(MM_PPD_BASE>>39) |= PF_COW;
+       TMPMAPLVL4(MM_PPD_BASE>>39) &= ~PF_WRITE;
        
        // #5 Set fractal mapping
-       TMPMAPLVL4(508) = ret | 3;      // Main
-       TMPMAPLVL4(509) = 0;    // Temp
+       TMPMAPLVL4(MM_FRACTAL_BASE>>39) = ret | 3;      // Main
+       TMPMAPLVL4(MM_TMPFRAC_BASE>>39) = 0;    // Temp
        
        // #6 Create kernel stack
        //  tThread->KernelStack is the top
        //  There is 1 guard page below the stack
        kstackbase = Proc_GetCurThread()->KernelStack - KERNEL_STACK_SIZE;
 
-       Log("MM_Clone: kstackbase = %p", kstackbase);
-       
+       // Clone stack
        TMPMAPLVL4(MM_KSTACK_BASE >> PML4_SHIFT) = 0;
        for( i = 1; i < KERNEL_STACK_SIZE/0x1000; i ++ )
        {
@@ -839,9 +843,6 @@ tPAddr MM_Clone(void)
                tVAddr  tmpmapping;
                MM_MapEx(kstackbase+i*0x1000, phys, 1, 0);
                
-               Log_Debug("MM", "MM_Clone: Cloning stack page %p from %P to %P",
-                       kstackbase+i*0x1000, MM_GetPhysAddr( kstackbase+i*0x1000 ), phys
-                       );
                tmpmapping = MM_MapTemp(phys);
                if( MM_GetPhysAddr( kstackbase+i*0x1000 ) )
                        memcpy((void*)tmpmapping, (void*)(kstackbase+i*0x1000), 0x1000);
@@ -867,7 +868,7 @@ void MM_int_ClearTableLevel(tVAddr VAddr, int LevelBits, int MaxEnts)
        Uint64  * const table_bases[] = {&PAGETABLE(0), &PAGEDIR(0), &PAGEDIRPTR(0), &PAGEMAPLVL4(0)};
        Uint64  *table = table_bases[(LevelBits-12)/9] + (VAddr >> LevelBits);
         int    i;
-       Log("MM_int_ClearTableLevel: (VAddr=%p, LevelBits=%i, MaxEnts=%i)", VAddr, LevelBits, MaxEnts);
+//     Log("MM_int_ClearTableLevel: (VAddr=%p, LevelBits=%i, MaxEnts=%i)", VAddr, LevelBits, MaxEnts);
        for( i = 0; i < MaxEnts; i ++ )
        {
                // Skip non-present tables

diff --git a/Kernel/arch/x86_64/proc.c b/Kernel/arch/x86_64/proc.c
index 50f712f..415901f 100644 (file)
--- a/Kernel/arch/x86_64/proc.c
+++ b/Kernel/arch/x86_64/proc.c
@@ -16,7 +16,7 @@
 #include <hal_proc.h>
 
 // === FLAGS ===
-#define DEBUG_TRACE_SWITCH     1
+#define DEBUG_TRACE_SWITCH     0
 #define BREAK_ON_SWITCH        0       // Break into bochs debugger on a task switch
 
 // === CONSTANTS ===
@@ -413,7 +413,7 @@ void Proc_Start(void)
        __asm__ __volatile__("sti");
        #endif
        MM_FinishVirtualInit();
-       Log("Multithreading started");
+       Log_Log("Proc", "Multithreading started");
 }
 
 /**
@@ -490,13 +490,15 @@ int Proc_Clone(Uint Flags)
        newThread->KernelStack = cur->KernelStack;
        newThread->SavedState.RIP = rip;
 
-       // DEBUG        
+       // DEBUG
+       #if 0
        Log("New (Clone) %p, rsp = %p, cr3 = %p", rip, newThread->SavedState.RSP, newThread->MemState.CR3);
        {
                Uint cr3;
                __asm__ __volatile__ ("mov %%cr3, %0" : "=r" (cr3));
                Log("Current CR3 = 0x%x, PADDR(RSP) = 0x%x", cr3, MM_GetPhysAddr(newThread->SavedState.RSP));
        }
+       #endif
        // /DEBUG
        
        // Lock list and add to active
@@ -573,7 +575,6 @@ Uint Proc_MakeUserStack(void)
        for( ; i < USER_STACK_SZ/0x1000; i++ )
        {
                tPAddr  alloc = MM_Allocate( base + (i<<12) );
-               Log_Debug("Proc", "Proc_MakeUserStack: alloc = %P", alloc);
                if( !alloc )
                {
                        // Error
@@ -634,9 +635,8 @@ void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP)
                        CS, SS);
                Threads_Exit(0, -1);
        }
-       Log("Proc_StartProcess: (SS=%x, Stack=%p, Flags=%x, CS=%x, IP=%p)",
-               SS, Stack, Flags, CS, IP);
-       MM_DumpTables(0, USER_MAX);
+//     Log("Proc_StartProcess: (SS=%x, Stack=%p, Flags=%x, CS=%x, IP=%p)", SS, Stack, Flags, CS, IP);
+//     MM_DumpTables(0, USER_MAX);
        if(CS == 0x1B)
        {
                // 32-bit return
@@ -724,12 +724,12 @@ void Proc_Reschedule(void)
                return ;
 
        #if DEBUG_TRACE_SWITCH
-       LogF("\nSwitching to task %i, CR3 = 0x%x, RIP = %p, RSP = %p, KStack = %p\n",
-               nextthread->TID,
+       LogF("\nSwitching to task CR3 = 0x%x, RIP = %p, RSP = %p - %i (%s)\n",
                nextthread->MemState.CR3,
                nextthread->SavedState.RIP,
                nextthread->SavedState.RSP,
-               nextthread->KernelStack
+               nextthread->TID,
+               nextthread->ThreadName
                );
        #endif
 

diff --git a/Kernel/arch/x86_64/start32.asm b/Kernel/arch/x86_64/start32.asm
index da0739b..d38c993 100644 (file)
--- a/Kernel/arch/x86_64/start32.asm
+++ b/Kernel/arch/x86_64/start32.asm
@@ -70,7 +70,7 @@ start:
 
        ; Enable paging
        mov eax, cr0
-       or eax, 0x80000000
+       or eax, 0x80010000      ; PG & WP
        mov cr0, eax
 
        ; Load GDT

diff --git a/Kernel/syscalls.c b/Kernel/syscalls.c
index 742b082..e304b40 100644 (file)
--- a/Kernel/syscalls.c
+++ b/Kernel/syscalls.c
@@ -68,7 +68,6 @@ void SyscallHandler(tSyscallRegs *Regs)
        case SYS_CLONE:
                // Call clone system call
                ret = Proc_Clone(Regs->Arg1);
-               Log("Proc_Clone returned %i", ret);
                // Change user stack if a new stack address is passed
                if(ret == 0 && Regs->Arg2)
                        Regs->StackPointer = Regs->Arg2;