some test things
This commit is contained in:
@@ -2,7 +2,7 @@
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OBJS = bin/boot.o bin/kernel.o bin/idt.o bin/isr.o bin/screen.o \
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OBJS = bin/boot.o bin/kernel.o bin/idt.o bin/isr.o bin/screen.o \
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bin/utils.o bin/string.o bin/stdio.o bin/disk.o bin/pic.o bin/pit.o \
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bin/utils.o bin/string.o bin/stdio.o bin/disk.o bin/pic.o bin/pit.o \
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bin/keyboard.o bin/paging.o bin/heap.o bin/page_alloc.o bin/page_tables.o \
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bin/keyboard.o bin/paging.o bin/heap.o bin/page_alloc.o bin/page_tables.o \
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bin/fat.o bin/task.o bin/switch.o bin/sys_exit.o
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bin/fat.o bin/task.o bin/switch.o bin/sys_exit.o bin/gdt.o
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# Define the compiler and assembler
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# Define the compiler and assembler
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CC = gcc -D__is_katauos
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CC = gcc -D__is_katauos
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@@ -48,7 +48,7 @@ image:
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sudo losetup -D
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sudo losetup -D
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test:
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test:
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qemu-system-i386 -drive file=boot.iso,media=disk,format=raw -m 512M -d int
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qemu-system-i386 -drive file=boot.iso,media=disk,format=raw -m 4096M -d int
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#qemu-system-i386 -s -S -kernel myos.bin
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#qemu-system-i386 -s -S -kernel myos.bin
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debug:
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debug:
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@@ -120,6 +120,9 @@ bin/task.o: src/tasking/task.c
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bin/sys_exit.o: src/tasking/sys_exit.asm
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bin/sys_exit.o: src/tasking/sys_exit.asm
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$(AS) $(ASFLAGS) $< -o $@
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$(AS) $(ASFLAGS) $< -o $@
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bin/gdt.o: src/kernel/gdt.c
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$(CC) $(CFLAGS) -c $< -o $@
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clean:
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clean:
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rm -rf bin/
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rm -rf bin/
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rm -f $(OUTPUT)
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rm -f $(OUTPUT)
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@@ -1,17 +1,45 @@
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OUTPUT_FORMAT(elf32-i386)
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OUTPUT_FORMAT(elf32-i386)
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ENTRY(start)
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ENTRY(start)
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vaddr = 0xC0000000; /* virtual start address */
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paddr = 0x100000; /* physical address at 1MB */
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SECTIONS
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SECTIONS
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{
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{
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. = 0x100000;
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. = 0x100000;
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.setup ALIGN(4096) :
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{
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*(.setup)
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}
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. += vaddr;
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.text BLOCK(4K) : ALIGN(4K) {
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.text BLOCK(4K) : ALIGN(4K) {
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*(.multiboot)
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*(.text)
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*(.text)
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}
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}
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.rodata BLOCK(4K) : ALIGN(4K) { *(.rodata) }
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_etext = .;
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.data BLOCK(4K) : ALIGN(4K) { *(.data) }
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.bss BLOCK(4K) : ALIGN(4K) {
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.data ALIGN(4096) : AT(ADDR(.data) - vaddr)
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*(.COMMON)
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{
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*(.bss)
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*(.data)
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*(.rodata*)
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}
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}
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kernel_end = .;
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_edata = .;
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/* uninitialized data */
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.bss ALIGN(4096) : AT(ADDR(.bss) - vaddr)
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{
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*(COMMON*)
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*(.bss*)
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}
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_end = .;
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/DISCARD/ :
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{
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*(.comment)
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*(.eh_frame)
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*(.note*)
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}
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}
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}
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+92
-66
@@ -1,14 +1,53 @@
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bits 32
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bits 32
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section .multiboot
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%define CR0_MP 0x00000002 /* bit 01 -> enable monitor coprocessor */
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%define CR0_NE 0x00000020 /* bit 05 -> enable native x87 FPU mode */
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%define CR0_WP 0x00010000 /* bit 16 -> enable write protect (for CoW) */
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%define CR0_AM 0x00040000 /* bit 18 -> enable alignment checking */
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%define CR0_PG 0x80000000 /* bit 31 -> enable paging */
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%define PAGE_OFFSET 0xC0000000
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%define GDT_BASE (0xFFFFFFFF - (PAGE_OFFSET - 1))
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section .setup
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align 4
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align 4
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tmp_gdtr:
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dw ((3 * 8) - 1)
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tmp_gdta:
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dd tmp_gdt
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align 4
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tmp_gdt:
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; null entry
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dw 0x0000
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dw 0x0000
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dw 0x0000
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dw 0x0000
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; /* KERNEL CODE */
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dw 0xFFFF ; /* segment limit 15-00 */
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dw 0x0000 ; /* base address 15-00 */
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db 0x00 ; /* base address 23-16 */
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db 0x9A ; /* P=1 DPL=00 S=1 TYPE=1010 (exec/read) */
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db 0xCF ; /* G=1 DB=1 0=0 AVL=0 SEGLIM=1111 */
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db GDT_BASE >> 24 ; /* base address 31-24 */
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; /* KERNEL DATA */
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dw 0xFFFF ; /* segment limit 15-00 */
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dw 0x0000 ; /* base address 15-00 */
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db 0x00 ; /* base address 23-16 */
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db 0x92 ; /* P=1 DPL=00 S=1 TYPE=0010 (read/write) */
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db 0xCF ; /* G=1 DB=1 0=0 AVL=0 SEGLIM=1111 */
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db GDT_BASE >> 24 ; /* base address 31-24 */
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align 4
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multiboot_header:
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dd 0x1BADB002
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dd 0x1BADB002
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dd 0x00
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dd 0x00
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dd - (0x1BADB002 + 0x00)
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dd - (0x1BADB002 + 0x00)
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section .data
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dd 0
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align 4
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dd 0
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multiboot_info:
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dd 0
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dd 0
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dd 0
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dd 0
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dd 0
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dd 0
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@@ -17,78 +56,65 @@ multiboot_info:
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dd 0
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dd 0
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dd 0
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dd 0
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global tss
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; section .text
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global tss_end
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align 4
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tss:
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dd 0 ; 0-3
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dd stack_top ; 4-7
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dd DATA_SEG ; 8-11
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dd 0 ; 12-15
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dd 0 ; 16-19
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dd 0 ; 20-23
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dd 0 ; 24-27
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dd 0 ; 28-31
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dd 0 ; 32-35
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dd 0 ; 36-39
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dd 0 ; 40-43
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dd 0 ; 44-47
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dd 0 ; 48-51
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dd 0 ; 52-55
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dd 0 ; 56-59
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dd 0 ; 60-63
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dd 0 ; 64-67
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dd 0 ; 68-71
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dd DATA_SEG ; 72-75
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dd CODE_SEG ; 76-79
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dd DATA_SEG ; 80-83
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dd DATA_SEG ; 84-87
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dd DATA_SEG ; 88-91
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dd DATA_SEG ; 92-95
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dd 0 ; 96-99
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dw 0 ; 100-101
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dw 104 ; 102-103
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tss_end:
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section .bss
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stack_bottom:
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resb 16384
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stack_top:
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section .gdt
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%include "src/gdt.asm"
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section .text
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global start:function (start.end - start)
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global start:function (start.end - start)
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extern kmain ; this function is gonna be located in our c code(kernel.c)
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extern kmain ; this function is gonna be located in our c code(kernel.c)
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extern get_last_boot_addr
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extern gdt_init
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extern bss_init
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extern setup_tmp_pgdir
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align 4
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start:
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start:
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mov esp, stack_top
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; mov esp, stack_top
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cli
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cli
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push ebx ; Сохраняем оригинальный ebx (указатель Multiboot)
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; push ebx ; Сохраняем оригинальный ebx (указатель Multiboot)
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lgdt [gdt]
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;lgdt [gdt]
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lgdt [tmp_gdtr]
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; Заполняем адрес TSS в дескрипторе GDT
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mov cx, 0x10 ; data segment
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mov eax, tss ; Получаем 32-битный адрес tss
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mov ds, cx
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mov ebx, gdt_tss ; Адрес дескриптора TSS в GDT
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mov es, cx
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mov [ebx + 2], ax ; Нижние 16 бит адреса TSS
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mov fs, cx
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shr eax, 16 ; Сдвигаем для доступа к старшим битам
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mov gs, cx
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mov [ebx + 4], al ; Средние 8 бит адреса TSS
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mov ss, cx
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mov [ebx + 7], ah ; Верхние 8 бит адреса TSS
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jmp 0x8:.huita ; 0x8 - code segment
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mov ax, DATA_SEG
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.text
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mov ds, ax
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mov es, ax
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mov fs, ax
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mov gs, ax
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mov ss, ax
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jmp CODE_SEG:.huita
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align 4
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.huita:
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.huita:
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mov ax, TSS_SEG
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mov esp, PAGE_OFFSET + 0x10000 ; default stack address
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ltr ax
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push 0
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popf ; reset EFLAGS
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push ebx ; save Multiboot info structure
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push eax ; save Multiboot magic value
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call setup_tmp_pgdir
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mov cr3, eax
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mov eax, cr0
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and eax, 0x00000011 ; disable all, preserve ET & PE (GRUB)
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or eax, 0x80000000 ; CR0_PG ; enable PG
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or eax, 0x40000 ; CR0_AM ; enable AM
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or eax, 0x10000 ; CR0_WP ; enable WP
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or eax, 0x20 ; CR0_NE ; enable NE
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or eax, 0x2 ; CR0_MP ; enable MP
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mov cr0, eax
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call bss_init ; initialize BSS segment
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call gdt_init ; setup and load definitive GDT
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call get_last_boot_addr
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pop ecx ; restore Multiboot magic value
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pop ebx ; restore Multiboot info structure
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push eax ; save last boot address
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push ebx ; save Multiboot info structure
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push ecx ; save Multiboot magic value
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pop ebx ; Восстанавливаем оригинальный ebx
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pop ebx ; Восстанавливаем оригинальный ebx
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push ebx ; Передаем его в kmain
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push ebx ; Передаем его в kmain
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call kmain
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call kmain
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@@ -0,0 +1,171 @@
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//#include "../include/gdt.h"
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#include <stdint.h>
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#include "../include/string.h"
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struct desc_r {
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uint16_t limit;
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uint32_t base_addr;
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} __attribute__((packed));
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struct seg_desc {
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unsigned sd_lolimit : 16; /* segment limit 0-15 bits */
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unsigned sd_lobase : 24; /* base address 0-23 bits */
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unsigned sd_loflags : 8; /* flags (P, DPL, S and TYPE) */
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unsigned sd_hilimit : 4; /* segment limit 16-19 bits */
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unsigned sd_hiflags : 4; /* flags (G, DB, 0 and AVL) */
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unsigned sd_hibase : 8; /* base address 24-31 bits */
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} __attribute__((packed));
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struct gate_desc {
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unsigned gd_looffset: 16; /* offset 0-15 bits */
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unsigned gd_selector: 16; /* segment selector */
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unsigned gd_flags : 16; /* flags (P, DPL, TYPE, 0 and NULL) */
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unsigned gd_hioffset: 16; /* offset 16-31 bits */
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} __attribute__((packed));
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extern char _end[], _edata[];
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#define KERNEL_CS 0x08 /* kernel code segment */
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#define KERNEL_DS 0x10 /* kernel data segment */
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#define USER_CS 0x18 /* user code segment */
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#define USER_DS 0x20 /* user data segment */
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#define TSS 0x28 /* TSS segment */
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|
void load_gdt(uint32_t gdt_ptr) {
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|
asm volatile (
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"lgdt (%0)\n\t"
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"movw %1, %%ax\n\t"
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"movw %%ax, %%ds\n\t"
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"movw %%ax, %%es\n\t"
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"movw %%ax, %%fs\n\t"
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|
"movw %%ax, %%gs\n\t"
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||||||
|
"movw %%ax, %%ss\n\t"
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"ljmp %2, $1f\n\t"
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|
"1:\n\t"
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|
:
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|
: "r" (gdt_ptr), "i" (KERNEL_DS), "i" (KERNEL_CS)
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|
: "eax"
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|
);
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||||||
|
}
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||||||
|
|
||||||
|
#define PAGE_SIZE 4096
|
||||||
|
#define PAGE_SHIFT 0x0C
|
||||||
|
|
||||||
|
#define PAGE_MASK ~(PAGE_SIZE - 1) /* 0xFFFFF000 */
|
||||||
|
#define PAGE_ALIGN(addr) (((addr) + (PAGE_SIZE - 1)) & PAGE_MASK)
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||||||
|
|
||||||
|
#define KERNEL_BSS_SIZE ((int)_end - (int)_edata)
|
||||||
|
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||||||
|
#define NR_GDT_ENTRIES 6 /* entries in GDT descriptor */
|
||||||
|
#define NR_IDT_ENTRIES 256 /* entries in IDT descriptor */
|
||||||
|
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||||||
|
/* low flags of Segment Descriptors */
|
||||||
|
#define SD_CODE 0x0A /* CODE Exec/Read */
|
||||||
|
#define SD_DATA 0x02 /* DATA Read/Write */
|
||||||
|
|
||||||
|
#define SD_32INTRGATE 0x0E /* 32-bit Interrupt Gate (0D110) */
|
||||||
|
#define SD_32TRAPGATE 0x0F /* 32-bit Trap Gate (0D111) */
|
||||||
|
|
||||||
|
#define SD_CD 0x10 /* 0 = system / 1 = code/data */
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||||||
|
#define SD_DPL0 0x00 /* priority level 0 (kernel) */
|
||||||
|
#define SD_DPL3 0x60 /* priority level 3 (user) */
|
||||||
|
#define SD_PRESENT 0x80 /* segment present or valid */
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||||||
|
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||||||
|
/* high flags Segment Descriptors */
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||||||
|
#define SD_OPSIZE32 0x04 /* 32-bit code and data segments */
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||||||
|
#define SD_PAGE4KB 0x08 /* page granularity (4KB) */
|
||||||
|
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||||||
|
/* low flags of the TSS Descriptors */
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||||||
|
#define SD_TSSPRESENT 0x89 /* TSS present and not busy flag */
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||||||
|
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||||||
|
/* EFLAGS */
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||||||
|
#define EF_IOPL 12 /* IOPL bit */
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||||||
|
|
||||||
|
#define KERNEL_CS 0x08 /* kernel code segment */
|
||||||
|
#define KERNEL_DS 0x10 /* kernel data segment */
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||||||
|
#define USER_CS 0x18 /* user code segment */
|
||||||
|
#define USER_DS 0x20 /* user data segment */
|
||||||
|
#define TSS 0x28 /* TSS segment */
|
||||||
|
|
||||||
|
|
||||||
|
struct tss_entry_struct {
|
||||||
|
uint32_t prev_tss; // The previous TSS - with hardware task switching these form a kind of backward linked list.
|
||||||
|
uint32_t esp0; // The stack pointer to load when changing to kernel mode.
|
||||||
|
uint32_t ss0; // The stack segment to load when changing to kernel mode.
|
||||||
|
// Everything below here is unused.
|
||||||
|
uint32_t esp1; // esp and ss 1 and 2 would be used when switching to rings 1 or 2.
|
||||||
|
uint32_t ss1;
|
||||||
|
uint32_t esp2;
|
||||||
|
uint32_t ss2;
|
||||||
|
uint32_t cr3;
|
||||||
|
uint32_t eip;
|
||||||
|
uint32_t eflags;
|
||||||
|
uint32_t eax;
|
||||||
|
uint32_t ecx;
|
||||||
|
uint32_t edx;
|
||||||
|
uint32_t ebx;
|
||||||
|
uint32_t esp;
|
||||||
|
uint32_t ebp;
|
||||||
|
uint32_t esi;
|
||||||
|
uint32_t edi;
|
||||||
|
uint32_t es;
|
||||||
|
uint32_t cs;
|
||||||
|
uint32_t ss;
|
||||||
|
uint32_t ds;
|
||||||
|
uint32_t fs;
|
||||||
|
uint32_t gs;
|
||||||
|
uint32_t ldt;
|
||||||
|
uint16_t trap;
|
||||||
|
uint16_t iomap_base;
|
||||||
|
} __packed;
|
||||||
|
|
||||||
|
void bss_init()
|
||||||
|
{
|
||||||
|
memset((void *)((int)_edata), 0, KERNEL_BSS_SIZE);
|
||||||
|
}
|
||||||
|
|
||||||
|
uint32_t get_last_boot_addr()
|
||||||
|
{
|
||||||
|
return ((unsigned int)_end & PAGE_MASK) + PAGE_SIZE;
|
||||||
|
}
|
||||||
|
|
||||||
|
struct seg_desc gdt[NR_GDT_ENTRIES];
|
||||||
|
|
||||||
|
struct desc_r gdtr = {
|
||||||
|
sizeof(gdt) - 1,
|
||||||
|
(unsigned int)&gdt
|
||||||
|
};
|
||||||
|
|
||||||
|
static void gdt_set_entry(int num, unsigned int base_addr, unsigned int limit, char loflags, char hiflags)
|
||||||
|
{
|
||||||
|
num /= sizeof(struct seg_desc);
|
||||||
|
gdt[num].sd_lolimit = limit & 0xFFFF;
|
||||||
|
gdt[num].sd_lobase = base_addr & 0xFFFFFF;
|
||||||
|
gdt[num].sd_loflags = loflags;
|
||||||
|
gdt[num].sd_hilimit = (limit >> 16) & 0x0F;
|
||||||
|
gdt[num].sd_hiflags = hiflags;
|
||||||
|
gdt[num].sd_hibase = (base_addr >> 24) & 0xFF;
|
||||||
|
}
|
||||||
|
|
||||||
|
void gdt_init(void)
|
||||||
|
{
|
||||||
|
unsigned char loflags;
|
||||||
|
|
||||||
|
gdt_set_entry(0, 0, 0, 0, 0); /* null descriptor */
|
||||||
|
|
||||||
|
loflags = SD_CODE | SD_CD | SD_DPL0 | SD_PRESENT;
|
||||||
|
gdt_set_entry(KERNEL_CS, 0, 0xFFFFFFFF, loflags, SD_OPSIZE32 | SD_PAGE4KB);
|
||||||
|
loflags = SD_DATA | SD_CD | SD_DPL0 | SD_PRESENT;
|
||||||
|
gdt_set_entry(KERNEL_DS, 0, 0xFFFFFFFF, loflags, SD_OPSIZE32 | SD_PAGE4KB);
|
||||||
|
|
||||||
|
loflags = SD_CODE | SD_CD | SD_DPL3 | SD_PRESENT;
|
||||||
|
gdt_set_entry(USER_CS, 0, 0xFFFFFFFF, loflags, SD_OPSIZE32 | SD_PAGE4KB);
|
||||||
|
loflags = SD_DATA | SD_CD | SD_DPL3 | SD_PRESENT;
|
||||||
|
gdt_set_entry(USER_DS, 0, 0xFFFFFFFF, loflags, SD_OPSIZE32 | SD_PAGE4KB);
|
||||||
|
|
||||||
|
loflags = SD_TSSPRESENT;
|
||||||
|
gdt_set_entry(TSS, 0, sizeof(struct tss_entry_struct), loflags, SD_OPSIZE32);
|
||||||
|
|
||||||
|
load_gdt((unsigned int)&gdtr);
|
||||||
|
}
|
||||||
@@ -1,10 +1,77 @@
|
|||||||
#include "../include/paging.h"
|
#include "../include/paging.h"
|
||||||
#include <stdint.h>
|
#include <stdint.h>
|
||||||
|
#include "../include/multiboot.h"
|
||||||
|
#include "../include/string.h"
|
||||||
|
|
||||||
uint32_t kernel_page_directory[1024] __attribute__((aligned(4096)));
|
uint32_t kernel_page_directory[1024] __attribute__((aligned(4096)));
|
||||||
uint32_t kernel_page_table[1024] __attribute__((aligned(4096)));
|
uint32_t kernel_page_table[1024] __attribute__((aligned(4096)));
|
||||||
uint32_t user_page_table[1024] __attribute__((aligned(4096)));
|
uint32_t user_page_table[1024] __attribute__((aligned(4096)));
|
||||||
|
|
||||||
|
#define PAGE_OFFSET 0xC0000000
|
||||||
|
#define PAGE_SIZE 4096
|
||||||
|
|
||||||
|
#define PAGE_PRESENT 0x1
|
||||||
|
#define PAGE_RW 0x002 /* Read/Write */
|
||||||
|
#define PAGE_USER 0x004 /* User */
|
||||||
|
#define PAGE_NOALLOC 0x200 /* No Page Allocated (OS managed) */
|
||||||
|
|
||||||
|
#define PAGE_SHIFT 0x0C
|
||||||
|
#define PAGE_MASK ~(PAGE_SIZE - 1) /* 0xFFFFF000 */
|
||||||
|
|
||||||
|
#define GDT_BASE (0xFFFFFFFF - (PAGE_OFFSET - 1))
|
||||||
|
|
||||||
|
#define GET_PGDIR(address) ((unsigned int)((address) >> 22) & 0x3FF)
|
||||||
|
#define GET_PGTBL(address) ((unsigned int)((address) >> 12) & 0x3FF)
|
||||||
|
|
||||||
|
#define PAGE_ALIGN(addr) (((addr) + (PAGE_SIZE - 1)) & PAGE_MASK)
|
||||||
|
|
||||||
|
unsigned int *kpage_dir;
|
||||||
|
|
||||||
|
unsigned int setup_tmp_pgdir(unsigned int magic, unsigned int info)
|
||||||
|
{
|
||||||
|
int n, pd;
|
||||||
|
unsigned int addr, memksize;
|
||||||
|
unsigned int *pgtbl;
|
||||||
|
struct multiboot_info *mbi;
|
||||||
|
|
||||||
|
if(magic != MULTIBOOT_BOOTLOADER_MAGIC) {
|
||||||
|
/* 4MB of memory assumed */
|
||||||
|
memksize = 4096;
|
||||||
|
} else {
|
||||||
|
mbi = (struct multiboot_info *)(PAGE_OFFSET + info);
|
||||||
|
if(!(mbi->flags & MULTIBOOT_INFO_MEMORY)) {
|
||||||
|
/* 4MB of memory assumed */
|
||||||
|
memksize = 4096;
|
||||||
|
} else {
|
||||||
|
/* we need to add the first 1MB to memksize */
|
||||||
|
memksize = (unsigned int)mbi->mem_upper + 1024;
|
||||||
|
/* CONFIG_VM_SPLIT22 marks the maximum physical memory supported */
|
||||||
|
if(memksize > ((0xFFFFFFFF - PAGE_OFFSET) / 1024)) {
|
||||||
|
memksize = (0xFFFFFFFF - PAGE_OFFSET) / 1024;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
addr = PAGE_OFFSET + (memksize * 1024) - memksize;
|
||||||
|
addr = PAGE_ALIGN(addr);
|
||||||
|
|
||||||
|
kpage_dir = (unsigned int *)addr;
|
||||||
|
memset(kpage_dir, 0, PAGE_SIZE);
|
||||||
|
|
||||||
|
addr += PAGE_SIZE;
|
||||||
|
pgtbl = (unsigned int *)addr;
|
||||||
|
memset(pgtbl, 0, memksize);
|
||||||
|
|
||||||
|
for(n = 0; n < memksize / sizeof(unsigned int); n++) {
|
||||||
|
pgtbl[n] = (n << PAGE_SHIFT) | PAGE_PRESENT | PAGE_RW;
|
||||||
|
if(!(n % 1024)) {
|
||||||
|
pd = n / 1024;
|
||||||
|
kpage_dir[pd] = (unsigned int)(addr + (PAGE_SIZE * pd) + GDT_BASE) | PAGE_PRESENT | PAGE_RW;
|
||||||
|
kpage_dir[GET_PGDIR(PAGE_OFFSET) + pd] = (unsigned int)(addr + (PAGE_SIZE * pd) + GDT_BASE) | PAGE_PRESENT | PAGE_RW;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return (unsigned int)kpage_dir - PAGE_OFFSET;
|
||||||
|
}
|
||||||
|
|
||||||
void enablePaging() {
|
void enablePaging() {
|
||||||
asm volatile (
|
asm volatile (
|
||||||
|
|||||||
Reference in New Issue
Block a user