Implemented Paging! Moved Kernel to 0x100000, Moved TSS above 1M, Moved V86 to 0x8000, Moved Usermode test to 0x400000, Moved lots of things!

entry.nasm

@@ -1,14 +1,9 @@
-[BITS 16]
 global entry
 entry:
-cli             ; no interrupts
-xor ax,ax
-mov ds, ax
 lgdt [gdt_desc]  ; load gdt register
-mov eax, cr0    ; set pmode bit
-or al, 1
-mov cr0, eax
-jmp 08h:Pmodecode
+jmp Pmodecode
+
+extern gdt_desc
 
 [BITS 32]
 Pmodecode:
@@ -30,110 +25,3 @@ hlt
 jmp hlt_loop
 
 extern start
-
-; currently unused first 8MB identity paging
-; taken from Linux 0.01
-setup_paging:
-mov ecx, 1024*3 ; 3K?
-xor eax, eax
-mov edi, 0x1000
-rep stosd ; zero first 3K for some reason
-mov edi, 0x4000
-mov eax, 0x800007 ; 8MB + 7
-std ; fill backwards
-.fill:
-stosd
-sub eax, 0x1000
-jge .fill
-cld ; fix direction
-mov dword [0x0000], 0x2000 + 7
-mov dword [0x0004], 0x3000 + 7
-mov eax, 0x1000
-mov cr3, eax ; page dir start 0x1000
-mov eax, cr0
-or eax, 0x80000000
-mov cr0, eax ; set paging bit
-ret ; flushes pre-fetch queue
-
-user_test:
-mov dword [0xb8000], 0x0f000f00 | 'U' | 's' << 16
-mov dword [0xb8004], 0x0f000f00 | 'e' | 'r' << 16
-mov dword [0xb8008], 0x0f000f00 | 'm' | 'o' << 16
-mov dword [0xb800C], 0x0f000f00 | 'd' | 'e' << 16
-mov word [0xb8010], 0x0f00 | '!'
-mov edi, 0xA0000
-xor eax, eax
-.loop:
-mov ecx, 320
-rep stosb
-inc al
-cmp eax, 200
-jl .loop
-mov eax, 0xA0000
-int 0x30 ; Exit
-xor ebx, ebx
-div bl ; Unhandled DIV0 exception
-
-global jmp_usermode_test
-jmp_usermode_test:
-pop eax ; return address
-mov ecx, esp ; return stack
-call save_current_task
-mov esp, 0x500000 ; usermode stack
-mov eax, 0x20 | 3
-mov ds, ax
-mov es, ax
-mov fs, ax
-mov gs, ax
-mov eax, esp
-push 0x20 | 3
-push eax
-pushfd
-push 0x18 | 3
-push user_test
-iret
-
-extern save_current_task
-
-global flushTSS
-flushTSS:
-mov ax, 0x28
-ltr ax
-ret
-
-extern tss_data
-
-global ivt
-ivt: dd 0x00000000
-
-gdt_desc:
-    dw gdt_end - gdt
-    dd gdt
-gdt:
-gdt_null: dq 0
-gdt_code: dw 0xFFFF, 0     ; bits 0-15 limit (4GB), bits 0-15 base address
-          db 0             ; bits 16-23 base address
-          db 10011010b     ; access byte
-          db 11001111b     ; bits 16-19 limit (4GB), 4 bits flags
-          db 0 ; bits 24-31 base address
-gdt_data: dw 0xFFFF, 0     ; bits 0-15 limit (4GB), bits 0-15 base address
-          db 0             ; bits 16-23 base address
-          db 10010010b     ; access byte
-          db 11001111b     ; bits 16-19 limit (4GB), 4 bits flags
-          db 0 ; bits 24-31 base address
-gdt_r3code: dw 0xFFFF, 0     ; bits 0-15 limit (4GB), bits 0-15 base address
-          db 0             ; bits 16-23 base address
-          db 0xFA     ; access byte
-          db 11001111b     ; bits 16-19 limit (4GB), 4 bits flags
-          db 0 ; bits 24-31 base address
-gdt_r3data: dw 0xFFFF, 0     ; bits 0-15 limit (4GB), bits 0-15 base address
-          db 0             ; bits 16-23 base address
-          db 0xF2     ; access byte
-          db 11001111b     ; bits 16-19 limit (4GB), 4 bits flags
-          db 0 ; bits 24-31 base address
-gdt_tss:  dw 0x2080, 0x0000;26*4, tss_data     ; bits 0-15 limit (4GB), bits 0-15 base address
-          db 0x2             ; bits 16-23 base address
-          db 0x89     ; access byte
-          db 00000000b     ; bits 16-19 limit (4GB), 4 bits flags
-          db 0 ; bits 24-31 base address
-gdt_end: