pushing bugs

Makefile

@@ -91,8 +91,8 @@ LibCDep=$(patsubst %.c,$(KOBJDIR)/%.d,$(LibCSources))
 LibCObj += $(KOBJDIR)/libc/atoi.o $(KOBJDIR)/libc/itoa.o
 
 # Kernel sources
-KernSources =	kernel/ke/cpuid.c                             \
-		kernel/ke/idt.c kernel/init/init.c                            \
+KernSources =	kernel/ke/cpuid.c kernel/mm/paging.c                           \
+		kernel/ke/idt.c kernel/init/init.c                             \
 		kernel/init/table.c kernel/io/cursor.c                         \
 		kernel/ke/log.c kernel/io/vga.c                                \
 		kernel/ke/panic.c kernel/mm/map.c                              \
@@ -161,6 +161,15 @@ $(KOBJDIR)/kernel/ke/idt.o: $(KALEIDDIR)/kernel/ke/idt.c \
 	@rm -f $@.1 $@.2
 	@echo ${CL2}[$@] ${CL}Compiled.${CL3}
 
+$(KOBJDIR)/kernel/mm/paging.o: $(KALEIDDIR)/kernel/mm/paging.c \
+	$(KALEIDDIR)/kernel/mm/paging.asm  | $(KOBJDIR)
+	@mkdir -p $(shell dirname $@)
+	@$(ASM) $(ASMFLAGS) $(KALEIDDIR)/kernel/mm/paging.asm -o $@.1
+	@$(KCC) $< -o $@.2
+	@$(LD) $(LDFLAGS) -r $@.1 $@.2 -o $@
+	@rm -f $@.1 $@.2
+	@echo ${CL2}[$@] ${CL}Compiled.${CL3}
+
 $(KOBJDIR)/kernel/mm/gdt.o: $(KALEIDDIR)/kernel/mm/gdt.c \
 	$(KALEIDDIR)/kernel/mm/gdt.asm  | $(KOBJDIR)
 	@mkdir -p $(shell dirname $@)

kaleid/kernel/init/init.c

@@ -24,6 +24,8 @@
 
 #include "init.h"
 
+void MmInitPaging(void);
+
 //
 // Entry point of the Kaleid kernel
 //
@@ -52,6 +54,7 @@ noreturn void BtStartKern(multiboot_info_t *mbInfo, uint mbMagic, void *codeSeg)
     KeEnableIRQs();
 
     // Several inits
+    MmInitPaging();
     MmInitHeap();
 
     // Start drivers

kaleid/kernel/mm/paging.asm

@@ -0,0 +1,24 @@
+
+global MmEnableWriteProtect
+global MmDisableWriteProtect
+global MmLoadPML4
+
+MmEnableWriteProtect:
+    push rax
+    mov rax, cr0
+    or rax, 1<<16
+    mov cr0, rax
+    pop rax
+    ret
+
+MmDisableWriteProtect:
+    push rax
+    mov rax, cr0
+    and rax, ~(1<<16)
+    mov cr0, rax
+    pop rax
+    ret
+
+MmLoadPML4:
+    mov cr3, rsi
+    ret

kaleid/kernel/mm/paging.c

@@ -0,0 +1,65 @@
+#include <kernel.h>
+
+#define PAGESIZE (4 * KB)
+#define PAGEALIGNED __attribute__((__aligned__(4096)))
+
+// Page directory pointer offset
+typedef uint    pdpe_t;
+
+// Page directory offset
+typedef uint    pde_t;
+
+// Page table entry
+typedef uint    pte_t;
+
+// paging.asm
+void MmLoadPML4(void *);
+void MmEnableWriteProtect(void);
+void MmDisableWriteProtect(void);
+
+enum
+{
+    MF_PRESENT      = 1 << 0,
+    MF_READWRITE    = 1 << 1,
+    MF_USERMODE     = 1 << 2,
+    MF_WRITETHR     = 1 << 3,
+    MF_CACHEDIS     = 1 << 4,
+    MF_ACCESSED     = 1 << 5,
+    MF_DIRTY        = 1 << 6
+};
+
+//-----------
+
+pdpe_t pml4[1024] ;
+
+// First PDPE of our pml4
+pde_t first_pdpe[1024] PAGEALIGNED;
+
+// First PDP of first_pdpe
+pte_t first_pde[1024] PAGEALIGNED;
+
+// First PTE of first_pde
+uint first_pte[1024] PAGEALIGNED;
+
+void MmInitPaging(void)
+{
+    size_t i;
+
+    // Set all PDPEs to kernel-mode not present
+    for (i = 0; i < 1024; i++) pml4[i] = MF_READWRITE;
+    for (i = 0; i < 1024; i++) first_pdpe[i] = MF_READWRITE;
+    for (i = 0; i < 1024; i++) first_pde[i] = MF_READWRITE;
+    
+    // Set all pages in first_pte to kernel-mode present
+    for (i = 0; i < 1024; i++) {
+        first_pte[i] = (i * PAGESIZE) | (MF_READWRITE | MF_PRESENT);
+    }
+    
+    // Install the first PTE
+    first_pde[0] = (uint)(ulong)first_pte | (MF_READWRITE | MF_PRESENT);
+    first_pdpe[0] = (uint)(ulong)first_pde | (MF_READWRITE | MF_PRESENT);
+    pml4[0] =  (uint)(ulong)first_pdpe | (MF_READWRITE | MF_PRESENT);
+
+    MmLoadPML4(pml4);
+}
+