paging is not very fun

.env

@@ -5,7 +5,7 @@ LD          = $(ARCH)-$(FORMAT)-ld
 AS          = nasm
 AR          = ar
 
-CFLAGS      = -ffreestanding -m32 -O2 -Wall -Wextra -pedantic # -DKERNEL_LOG
+CFLAGS      = -ffreestanding -m32 -O2 -Wall -Wextra -pedantic
-LDFLAGS     = -nostdlib
+LDFLAGS     = -nostdlib -export-dynamic
 
 QEMU        = qemu-system-i386

kernel/arch/i686/linker.ld

@@ -7,9 +7,9 @@ SECTIONS {
     kernel_start = .;
 
     .bootstrap : {
-        *(.bootstrap.data)
-        *(.bootstrap.stack)
         *(.bootstrap.text)
+        *(.bootstrap.data)
+        *(.bootstrap.bss)
     }
 
 	. += 0xC0000000;
@@ -30,7 +30,6 @@ SECTIONS {
 	{
 		*(COMMON)
 		*(.bss)
-		*(.stack)
 	}
 
     kernel_end = .;

kernel/include/arch.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <stddef.h>
+
 extern void arch_init(void *boot_info);
 extern void arch_update(void);
 extern void arch_halt(void);

kernel/include/arch/i686/acpi.h

@@ -102,5 +102,5 @@ struct FixedACPIDescriptionTable {
     struct GenericAddressStructure x_gpe1_block;
 };
 
-void acpi_init(void *rsdp);
+extern void acpi_init(void);
-void acpi_poweroff(void);
+extern void acpi_poweroff(void);

kernel/include/arch/i686/mboot.h

@@ -12,7 +12,7 @@ struct BootTag {
     uint32_t type;
     uint32_t size;
     union {
-        char cmdline[CMDLINE_MAX];
+        char cmdline[CMDLINE_MAX + 1];
         struct MemoryMap *memory_map;
         struct RootSystemDescriptionPointer *rsdp;
     } data;
@@ -26,9 +26,9 @@ struct BootInfo {
 
 enum BootTagID {
     ID_CMDLINE = 0,
-    iD_MEMORYMAP = 6,
+    ID_MEMORYMAP = 6,
     ID_RSDP = 14
 };
 
-void load_boot_info(void* boot_info);
+extern void load_boot_info(void* boot_info);
-bool get_boot_tag(enum BootTagID id, struct BootTag **tag);
+extern bool get_boot_tag(enum BootTagID id, struct BootTag **tag);

kernel/include/arch/i686/paging.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <stddef.h>
+
+struct page_directory_t { // 32 bits
+    unsigned int present       : 1;
+    unsigned int rw_flag       : 1;
+    unsigned int access_lvl    : 1; //0 is for only ring0. 1 is for anybody.
+    unsigned int write_through : 1;
+    unsigned int cache_off     : 1;
+    unsigned int accessed      : 1;
+    unsigned int zero          : 1;
+    unsigned int page_size     : 1;
+    unsigned int unused        : 4;
+    unsigned int tbl_addr      : 20;
+};
+
+struct page_table_t {  // 32 bits
+    unsigned int present       : 1;
+    unsigned int rw_flag       : 1;
+    unsigned int access_lvl    : 1; //0 is for only ring0. 1 is for anybody.
+    unsigned int write_through : 1;
+    unsigned int cache_off     : 1;
+    unsigned int accessed      : 1;
+    unsigned int dirty         : 1;
+    unsigned int zero          : 1;
+    unsigned int global        : 1;
+    unsigned int reserved      : 3;
+    unsigned int phys_addr     : 20;
+};
+
+extern void ident_map_addr(void *addr, size_t len);
+extern void ident_unmap_addr(void *addr, size_t len);

kernel/include/drivers/vga.h

@@ -27,6 +27,7 @@ enum vga_color {
 void vgatext_write_char(char c, enum vga_color color, uint8_t x, uint8_t y);
 void vgatext_write_data(uint16_t data, uint16_t index);
 void vgatext_write_buf(const uint16_t *buffer);
+
 void vgatext_cur_mov(uint8_t x, uint8_t y);
 void vgatext_cur_resize(uint8_t start, uint8_t end);
 void vgatext_cur_visible(bool visible);

kernel/include/memory.h

@@ -1,6 +1,13 @@
 #pragma once
 
+#include <stddef.h>
+
 extern int memory_lock(void);
 extern int memory_unlock(void);
 extern void *memory_alloc_page(int);
 extern int memory_free_page(void* ,int);
+
+extern void *malloc(size_t size);
+extern void free(void *ptr);
+extern void *calloc(size_t nobj, size_t size);
+extern void *realloc(void *p, size_t size);

kernel/include/time.h

@@ -36,6 +36,11 @@ extern struct Time get_utctime(void);
  */
 extern struct Time get_localtime(void);
 
+/**
+ * Return the time on the system clock
+ */
+extern size_t get_systemtime(void);
+
 /**
  * Converts the time into a string format
  * @param time the current time

kernel/src/arch/i686/acpi.c

@@ -1,3 +1,5 @@
+#include "arch/i686/mboot.h"
+#include "arch/i686/paging.h"
 #include <panic.h>
 #include <string.h>
 #include <stdbool.h>
@@ -73,20 +75,25 @@ static void read_s5_addr(void) {
     }
 }
 
-void acpi_init(void *ptr) {
+void acpi_init(void) {
-
+    struct BootTag *tag;
-    struct RootSystemDescriptionPointer *rsdp = ptr;
+    if (!get_boot_tag(ID_RSDP, &tag)) {
+        panic("Could not find RSDP");
+    }
+    struct RootSystemDescriptionPointer *rsdp = tag->data.rsdp;
     if (!checksum((uint8_t*) rsdp, sizeof(struct RootSystemDescriptionPointer))) {
         panic("RSDP checksum failed to validate");
     }
-
     uintptr_t rsdt_ptr = rsdp->rsdt_address;
     rsdt = (void *) rsdt_ptr;
+    ident_map_addr(rsdt, 1000);
     if (!checksum((uint8_t*) &rsdt->header, rsdt->header.length)) {
         panic("RSDT checksum failed to validate");
     }
-
+    return;
+    
     fadt = find_fadt();
+    
     if (fadt == NULL) {
         panic("Could not find FADT");
     }
@@ -98,6 +105,7 @@ void acpi_init(void *ptr) {
     read_s5_addr();
 
     outb(fadt->smi_command_port,fadt->acpi_enable);
+    panic("C");
 }
 
 void acpi_poweroff(void) {

kernel/src/arch/i686/arch.c

@@ -1,4 +1,5 @@
-#include <sys.h>
+#include "print.h"
+#include <arch.h>
 #include <arch/i686/asm.h>
 #include <arch/i686/acpi.h>
 #include <arch/i686/drivers/rtc.h>
@@ -14,9 +15,7 @@ void arch_init(void *boot_info) {
     pic_remap();
 
     load_boot_info(boot_info);
-
+    acpi_init();
-    /* havent refactored to work with paging yet */
-    // acpi_init();
     // memory_init();
 
     ps2ctrl_init();

kernel/src/arch/i686/drivers/rtc.c

@@ -1,6 +1,6 @@
 #include "time.h"
 #include <stdint.h>
-#include <sys.h>
+#include <arch.h>
 #include <arch/i686/drivers/rtc.h>
 #include <arch/i686/asm.h>
 
@@ -55,10 +55,9 @@ static void update_localtime(void) {
     localtime = time;
 
     // if tz is UTC, we dont need to do anythin
-    if (last_timezone == UTC) {
+    if (last_timezone == UTC) return;
-        cur_localtime = localtime;
+
-        return;
+    localtime.hour += last_timezone;
-    }
 
     // check if day rolled over
     change = localtime.hour < 0 ? -1 : localtime.hour >= 24 ? 1 : 0;
@@ -109,8 +108,6 @@ year:
 
     localtime.year -= 1900;
     
-    cur_localtime = localtime;
-
 }
 
 void rtc_update(void) {
@@ -137,6 +134,7 @@ void rtc_update(void) {
     update_localtime();
 
     cur_time = time;
+    cur_localtime = localtime;
 }
 
 struct Time rtc_utctime(void) {
@@ -147,6 +145,7 @@ struct Time rtc_localtime(enum Timezone tz) {
     if (tz != last_timezone) {
         last_timezone = tz;
         update_localtime();
+        cur_localtime = localtime;
     }
     return cur_localtime;
 }

kernel/src/arch/i686/drivers/vga.c

@@ -21,7 +21,7 @@ void vgatext_write_buf(const uint16_t *src) {
 }
 
 void vgatext_cur_mov(uint8_t x, uint8_t y) {
-;	const uint16_t pos = y * VGA_TEXT_W + x;
+	const uint16_t pos = y * VGA_TEXT_W + x;
  
 	outb(0x3D4, 0x0F);
 	outb(0x3D5, (uint8_t) (pos & 0xFF));

kernel/src/arch/i686/idt.c

@@ -2,7 +2,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <stdlib.h>
-#include <sys.h>
+#include <arch.h>
 #include <print.h>
 #include <panic.h>
 #include <arch/i686/pic.h>
@@ -10,8 +10,7 @@
 #include <time.h>
 #include <drivers/ps2kb.h>
 #include <drivers/ps2mouse.h>
-
+#include <arch/i686/asm.h>
-#include "tty/term.h"
 
 struct IdtEntry {
 	uint16_t isr_low;
@@ -41,31 +40,18 @@ enum IDTFlags {
 	IDT_FLAG_PRESENT = 0x80,
 };
 
-#define WIDTH 30
+static size_t timer = 0;
-static char buf[WIDTH];
-static int timer = -1;
 
 void idt_pic_eoi(uint8_t exception) {
 	pic_eoi(exception - PIC_REMAP_OFFSET);
 }
 
 void idt_pic_timer(void) {
-
 	timer += 1;
-    if (timer % 20 != 0) return;
+}
 
-    uint32_t state = term_save();
+size_t get_systemtime(void) {
-
+    return timer;
-    term_setfg(VGA_LIGHT_GREEN);
-	term_setpos(TERM_W - WIDTH - 1, 0);
-    for (size_t i = 0; i < WIDTH; i++) putchar(' ');
-	term_setpos(TERM_W - WIDTH - 1, 0);
-    
-    struct Time t = get_localtime();
-    timetostr(&t, "%a %b %d %Y %H:%M:%S", buf, WIDTH);
-    printk("%s", buf);
-
-	term_load(state);
 }
 
 void idt_pic_keyboard(void) {

kernel/src/arch/i686/mboot.c

@@ -1,3 +1,4 @@
+#include "print.h"
 #include <panic.h>
 #include <string.h>
 #include <arch/i686/mboot.h>
@@ -11,12 +12,13 @@ static void read_cmdline(struct BootTag *tag, char *data, uint8_t len) {
         panic("multiboot2 cmd line to long\nmax is %d but was provided %d\n",
               CMDLINE_MAX, len);
     memcpy(tag->data.cmdline, data, len);
+    tag->data.cmdline[len] = '\0';
     info.tags[ID_CMDLINE] = *tag;
 }
 
 static void read_memorymap(struct BootTag *tag, uint32_t *data) {
     tag->data.memory_map = (struct MemoryMap *) data;
-    info.tags[iD_MEMORYMAP] = *tag;
+    info.tags[ID_MEMORYMAP] = *tag;
 }
 
 static void read_rsdp(struct BootTag *tag, char *data) {
@@ -36,7 +38,7 @@ static uint32_t *read_tag(uint32_t *data) {
         case ID_CMDLINE:
             read_cmdline(&tag, (char *)(data + 2), data_len);
             break;
-        case iD_MEMORYMAP:
+        case ID_MEMORYMAP:
             read_memorymap(&tag, data + 2);
             break;
         case ID_RSDP:

kernel/src/arch/i686/memory.c

@@ -1,7 +1,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include <string.h>
-#include <sys.h>
+#include <arch.h>
 #include <panic.h>
 #include <arch/i686/memory.h>
 #include <arch/i686/mboot.h>
@@ -126,7 +126,7 @@ void memory_init(void) {
     kernel_end_addr = (uintptr_t) &kernel_end;
 
     struct BootTag *tag;
-    if (!get_boot_tag(iD_MEMORYMAP, &tag)) {
+    if (!get_boot_tag(ID_MEMORYMAP, &tag)) {
         panic("No multiboot memory map found");
     }
 

kernel/src/arch/i686/paging.asm

@@ -1,17 +1,20 @@
 global page_directory
+global page_tables
 global paging_init
 global paging_finish
 global KERNEL_MAPPING
 
-KERNEL_MAPPING   equ  0xC0000000
+KERNEL_MAPPING      equ  0xC0000000
-VGABUF   equ  0x000B8000
+VGABUF              equ  0x000B8000
+
+%define mapped(addr) addr - KERNEL_MAPPING
 
 section .bss
 align 4096
 page_directory:
-resb 4096
+resb 1024 * 4
-page_table1:
+page_tables:
-resb 4096
+resb 1024 * 1024 * 4
 
 section .bootstrap.text
 align 8
@@ -20,14 +23,14 @@ paging_init:
     extern kernel_end
 
 paging_load:
-    mov edi, page_table1 - KERNEL_MAPPING
+    mov edi, mapped(page_tables)
     mov esi, 0
     mov ecx, 1023
 
 paging_cmp:
     cmp esi, kernel_start
     jl paging_add
-    cmp esi, kernel_end - KERNEL_MAPPING
+    cmp esi, mapped(kernel_end)
     jge paging_map
 
     mov edx, esi
@@ -40,13 +43,27 @@ paging_add:
     loop paging_cmp
 
 paging_map:
-    mov dword [page_table1 - KERNEL_MAPPING + 1023 * 4], VGABUF | 0x003
-    mov dword [page_directory - KERNEL_MAPPING + 0], page_table1 - KERNEL_MAPPING + 0x003
-    mov dword [page_directory - KERNEL_MAPPING + 768 * 4], page_table1 - KERNEL_MAPPING + 0x003 
 
-    mov ecx, page_directory - KERNEL_MAPPING
+    lea eax, mapped(page_directory)
+    push eax
+    extern setup_pgdir
+    call mapped(setup_pgdir)
+    add esp, 0x04
+
+    ; map VGA buffer
+    mov dword [mapped(page_tables) + 1023 * 4], VGABUF + 0x003
+
+    ; map 8MB for the kernel
+    mov dword [mapped(page_directory) + 0 * 4], mapped(page_tables) + 0x003
+    mov dword [mapped(page_directory) + 1 * 4], mapped(page_tables) + 0x400000000 + 0x003
+    mov dword [mapped(page_directory) + 768 * 4], mapped(page_tables) + 0x003 
+    mov dword [mapped(page_directory) + 769 * 4], mapped(page_tables) + 0x400000000 + 0x003 
+
+    ; tell the MMU where the page dir is
+    mov ecx, mapped(page_directory)
     mov cr3, ecx
 
+    ; finally init paging
     mov ecx, cr0
     or ecx, 0x80010000
     mov cr0, ecx
@@ -56,7 +73,9 @@ paging_map:
 section .text
 align 8
 paging_finish:
-    mov dword [page_directory], 0
+    ; remove the 8MB ident mapping
+    mov dword [page_directory + 0 * 4], 0
+    mov dword [page_directory + 1 * 4], 0
     mov ecx, cr3
     mov cr3, ecx
     ret

kernel/src/arch/i686/paging.c

@@ -0,0 +1,71 @@
+#include "panic.h"
+#include "arch.h"
+#include <arch/i686/paging.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <print.h>
+
+extern struct page_directory_t page_directory[1024];
+extern struct page_table_t     page_tables[1024][1024];
+// static uintptr_t KERNEL_MAPPING = 0xC0000000;
+
+void setup_pgdir(struct page_directory_t pgdir[1024]) {
+    for(int i = 0; i < 1024; i++) {
+        pgdir[i].present    = 0;
+        pgdir[i].rw_flag    = 1;
+        pgdir[i].access_lvl = 0;
+    }
+}
+
+void paging_ident(struct page_table_t tbl[1024]) {
+    size_t size = 1024;
+    for(size_t i = 0; i < size; i++) {
+        tbl[i].rw_flag    = 1;
+        tbl[i].access_lvl = 0;
+        tbl[i].phys_addr  = i;
+        tbl[i].present    = 1;
+    }
+}
+
+void map_page(struct page_table_t tbl[1024], void *addr) {
+    uintptr_t ptr = (uintptr_t) addr;
+    ptr &= 0xfffff000;
+    ptr >>= 16;
+    for(size_t i = 0; i < 4096; i++) {
+        tbl[i].rw_flag    = 1;
+        tbl[i].access_lvl = 0;
+        tbl[i].phys_addr  = ptr / 4096 + i;
+        tbl[i].present    = 1;
+    }
+}
+
+void unmap_page(struct page_table_t tbl[1024]) {
+    for(size_t i = 0; i < 4096; i++) {
+        tbl[i].rw_flag    = 1;
+        tbl[i].access_lvl = 0;
+        tbl[i].phys_addr  = 0;
+        tbl[i].present    = 0;
+    }
+}
+
+void ident_map_addr(void *addr, size_t len) {
+    uintptr_t ptr = (uintptr_t) addr;
+    int i = ptr / 0x400000;
+    // int c = len / 0x1000 + (len % 0x1000 ? 1 : 0);
+    // for (; c > 0; c--, i++) {
+    //     paging_ident(page_tables[i]);
+    // }
+    paging_ident(page_tables[i]);
+}
+
+void ident_unmap_addr(void *addr, size_t len) {
+    uintptr_t ptr = (uintptr_t) addr;
+    int i = ptr / 0x1000;
+    int c = len / 0x1000 + (len % 0x1000 ? 1 : 0);
+    for (; c > 0; c--, i++) {
+        page_tables[i / 1024][i % 1024].present = 0;    
+        page_tables[i / 1024][i % 1024].rw_flag = 1;   
+        page_tables[i / 1024][i % 1024].access_lvl = 0;    
+    }
+}

kernel/src/arch/i686/pic.c

@@ -1,4 +1,4 @@
-#include <sys.h>
+#include <arch.h>
 #include <print.h>
 #include <arch/i686/pic.h>
 #include <arch/i686/asm.h>

kernel/src/arch/i686/start.asm

@@ -1,7 +1,6 @@
 global start
 bits 32
 
-
 ; create the multiboot header
 section .bootstrap.data
 align 8
@@ -17,7 +16,7 @@ mb_end:
 
 
 ; create the stack for bootstrapping
-section .bootstrap.stack
+section .bootstrap.bss
 align 16
 bootstrap_stack_start:
 resb 1024 ; 1 KiB
@@ -25,7 +24,7 @@ bootstrap_stack_end:
 
 
 ; create the stack for the kernel
-section .stack
+section .bss
 align 16
 stack_start:
 resb 16384 ; 16 KiB
@@ -46,6 +45,7 @@ start:
 
     jmp near load_kernel
 
+
 ; initalize kernel after it has been loaded in higher half
 section .text
 align 8
@@ -53,7 +53,7 @@ load_kernel:
     ; init stack
 	mov esp, stack_end
 	mov ebp, stack_end
-    
+
     ; load global descripter table
     extern load_gdt
     call load_gdt
@@ -64,14 +64,12 @@ load_kernel:
 
     ; initalize the FPU
     finit                                  
-    
-    ; push multiboot header
-    extern KERNEL_MAPPING
-    add ebx, KERNEL_MAPPING
-    push ebx
 
     ; start kernel
 	sti
+    extern KERNEL_MAPPING
+    add ebx, KERNEL_MAPPING
+    push ebx
     call kernel_main
     extern kernel_main
 	

kernel/src/main.c

@@ -3,12 +3,15 @@
 #include <drivers/ps2mouse.h>
 #include <panic.h>
 #include <print.h>
-#include <sys.h>
+#include <stddef.h>
+#include <arch.h>
 #include <math.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <term.h>
 
+#define WIDTH 30
+static char buf[WIDTH];
 static double x = 0, y = 0;
 
 void kernel_main(void *boot_info) {
@@ -23,7 +26,6 @@ void kernel_main(void *boot_info) {
 
     while(1) {
         arch_wait_int();
-        arch_update();
 
         struct Keycode code = ps2kb_get();
 	    if(code.key != KEY_NONE) {
@@ -52,6 +54,20 @@ void kernel_main(void *boot_info) {
             printk(" x%d y%d\n", (int)x, (int)y);
         }
 
+        uint32_t state = term_save();
+
+        term_setfg(VGA_LIGHT_GREEN);
+	    term_setpos(TERM_W - WIDTH - 1, 0);
+        for (size_t i = 0; i < WIDTH; i++) putchar(' ');
+	    term_setpos(TERM_W - WIDTH - 1, 0);
+    
+        struct Time t = get_localtime();
+        timetostr(&t, "%a %b %d %Y %H:%M:%S", buf, WIDTH);
+        printk("%s", buf);
+
+	    term_load(state);
+
+        arch_update();
         term_flush();
     } 
 }

kernel/src/memory.c

@@ -26,7 +26,7 @@ struct boundary_tag {
 
 #define MODE    MODE_BEST
 
-struct boundary_tag* l_freePages[MAXEXP];
+struct boundary_tag *l_freePages[MAXEXP];
 int                  l_completePages[MAXEXP];
 
 static int l_initialized = 0;
@@ -79,7 +79,7 @@ static inline void remove_tag(struct boundary_tag *tag) {
     tag->index = -1;
 }
 
-static inline struct boundary_tag* melt_left(struct boundary_tag *tag) {
+static inline struct boundary_tag *melt_left(struct boundary_tag *tag) {
     struct boundary_tag *left = tag->split_left;
                             
     left->real_size   += tag->real_size;
@@ -91,7 +91,7 @@ static inline struct boundary_tag* melt_left(struct boundary_tag *tag) {
 }
 
 
-static inline struct boundary_tag* absorb_right(struct boundary_tag *tag) {
+static inline struct boundary_tag *absorb_right(struct boundary_tag *tag) {
     struct boundary_tag *right = tag->split_right;
 
     remove_tag(right);
@@ -105,7 +105,7 @@ static inline struct boundary_tag* absorb_right(struct boundary_tag *tag) {
     return tag;
 }
 
-static inline struct boundary_tag* split_tag(struct boundary_tag* tag) {
+static inline struct boundary_tag *split_tag(struct boundary_tag *tag) {
     unsigned int remainder = tag->real_size - sizeof(struct boundary_tag) - tag->size;
 
     struct boundary_tag *new_tag = 
@@ -130,7 +130,7 @@ static inline struct boundary_tag* split_tag(struct boundary_tag* tag) {
     return new_tag;
 }
 
-static struct boundary_tag* allocate_new_tag(unsigned int size) {
+static struct boundary_tag *allocate_new_tag(unsigned int size) {
     unsigned int pages;
     unsigned int usage;
     struct boundary_tag *tag;
@@ -268,7 +268,7 @@ void free(void *ptr) {
     memory_unlock();
 }
 
-void* calloc(size_t nobj, size_t size) {
+void *calloc(size_t nobj, size_t size) {
     int real_size;
     void *p;
 
@@ -281,7 +281,7 @@ void* calloc(size_t nobj, size_t size) {
     return p;
 }
 
-void* realloc(void *p, size_t size) {
+void *realloc(void *p, size_t size) {
     void *ptr;
     struct boundary_tag *tag;
     size_t real_size;

kernel/src/panic.c

@@ -1,10 +1,15 @@
-#include <sys.h>
+#include <arch.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <panic.h>
 #include <print.h>
 #include <term.h>
 
+struct stackframe {
+  struct stackframe* ebp;
+  uint32_t eip;
+};
+
 __attribute__((noreturn))
 void _panic_impl(char* msg, int line, char* file, ...) {
 	arch_disable_int();

kernel/src/term.c

@@ -2,7 +2,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <string.h>
-#include <sys.h>
+#include <arch.h>
 #include <print.h>
 
 #include "drivers/vga.h"