Another attempt at implementing a block layer

kernel/drive.asm

@@ -1,70 +0,0 @@
-; Load a sector from drive.
-; IN    DX:AX   sector number (lba)
-;       BX      ptr to FCB
-; OUT	CL	Sector number
-;	CH	Cylinder number
-;	DH	Head number
-drive_chs_calc:
-  push bx      ; backup fcb ptr
-  mov bx, [bx+fcb_spt] ; nos is in BH now
-  push bx      ; backup nos
-  xor bh, bh   ; zero out nos so spt is left
-  div word bx  ; ax:temp     = (lba / spt)
-  inc dx       ; dx:sector   = (lba % spt) + 1
-  mov cl, dl   ; sector number
-
-  pop bx       ; restore nos
-  xchg bl, bh  ; put nos into bl
-  xor bh, bh   ; zero out spt
-  div word bx  ; ax:cylinder = (temp / nos)
-               ; dx:head     = (temp % nos)
-  mov ch, al   ; cylinder number
-  mov dh, dl   ; head number
-
-  pop bx       ; restore fcb ptr
-  ret
-
-; Load a sector from drive.
-; IN    DX:AX   sector number
-;	BX	ptr to FCB
-drive_read:
-  push ax
-  push cx
-  push dx
-  push bx
-  push si
-
-  mov cx, dx
-  or cx, ax
-  jz .fast
-
-  call drive_chs_calc
-
-  mov si, 5        ; retry count
-.try:
-  mov dl, [bx+fcb_drv] ; drive number
-  and dl, 0x7F
-  dec dl
-  mov ax, 0x0201
-  mov bx, diskbuf
-  ; try read
-  int 0x13
-  jnc .end
-  ; reset disk
-  mov ah, 0x00
-  int 0x13
-  ; loop with si
-  dec si
-  test si, si
-  jnz .try
-  stc
-.end:
-  pop si
-  pop bx
-  pop dx
-  pop cx
-  pop ax
-  ret
-.fast: ; fast lane for boot sector
-  inc cl
-  jmp .try