More work on the memory disk image driver

diff --git a/memdisk.asm b/memdisk.asm
index a690e66..b175d71 100644 (file)
--- a/memdisk.asm
+++ b/memdisk.asm
@@ -202,9 +202,6 @@ chstolba:
                add eax,ebx
                ret
 
-bcopy:
-               ; Do something here
-
                ; Set up registers as for a "Read", and compares against disk size
 setup_regs:
                call chstolba
@@ -219,6 +216,7 @@ setup_regs:
                add esi,[DiskBuf]
                cmp ebx,[DiskSize]
                jae .overrun
+               shr ecx,SECTORSIZE_LG2-1
                ret
 
 .overrun:      pop ax                  ; Drop return address
@@ -241,7 +239,7 @@ int15_e820:
                mov di,cs
                shr di,4
                add edi,E820Buf
-               mov ecx,24/4
+               mov ecx,24/2
                call bcopy
                add ebx, byte 12
                pop edi
@@ -285,7 +283,7 @@ Int15Start:
                cmp ah,88h
                je int15_88
 oldint15:      pop bp
-               jmp far [OldInt15]
+               jmp far [cs:OldInt15]
                
 int15_e801:
                mov ax,[cs:Mem1MB]
@@ -305,6 +303,58 @@ int15_88:
                mov ax,[cs:MemInt1588]
                jmp short int15_success
 
+;
+; Routine to copy in/out of high memory
+; esi = linear source address
+; edi = linear target address
+; ecx = 16-bit word count 
+;
+; Assumes cs = ds = es
+;
+bcopy:
+               push eax
+               push ebx
+               push edx
+               push ebp
+               push esi
+               push edi
+.copy_loop:
+               push ecx
+               cmp ecx,8000h
+               jna .safe_size
+               mov ecx,8000h
+.safe_size:
+               push ecx
+               mov eax, esi
+               mov [Mover_src1], si
+               shr eax, 16
+               mov [Mover_src1+2], al
+               mov [Mover_src2], ah
+               mov eax, edi
+               mov [Mover_dst1], di
+               shr eax, 16
+               mov [Mover_dst1+2], al
+               mov [Mover_dst2], ah
+               mov si,Mover
+               mov ah, 87h
+               int 15h
+               pop eax
+               pop ecx
+               pop edi
+               pop esi
+               jc .error
+               lea esi,[esi+2*eax]
+               lea edi,[edi+2*eax]
+               sub ecx, eax
+               jnz .copy_loop
+               ; CF = 0
+.error:
+               pop ebp
+               pop edx
+               pop ebx
+               pop eax
+               ret
+
                section .data
 Int13Funcs     dw Reset                ; 00h - RESET
                dw GetStatus            ; 01h - GET STATUS
@@ -348,6 +398,18 @@ Mem1MB             dd 0                    ; 1MB-16MB memory amount (1K)
 Mem16MB                dd 0                    ; 16MB-4G memory amount (64K)
 MemInt1588     dw 0                    ; 1MB-65MB memory amount (1K)
 
+               alignb 8, db 0
+Mover          dd 0, 0, 0, 0           ; Must be zero
+               dw 0ffffh               ; 64 K segment size
+Mover_src1:    db 0, 0, 0              ; Low 24 bits of source addy
+               db 93h                  ; Access rights
+               db 00h                  ; Extended access rights
+Mover_src2:    db 0                    ; High 8 bits of source addy
+Mover_dst1:    db 0, 0, 0              ; Low 24 bits of target addy
+               db 93h                  ; Access rights
+               db 00h                  ; Extended access rights
+Mover_dst2:    db 0                    ; High 8 bits of source addy
+
                section .bss
 OldInt13       resd 1                  ; INT 13h in chain
 OldInt15       resd 1                  ; INT 15h in chain

diff --git a/memdisk/memdisk.asm b/memdisk/memdisk.asm
index a690e66..b175d71 100644 (file)
--- a/memdisk/memdisk.asm
+++ b/memdisk/memdisk.asm
@@ -202,9 +202,6 @@ chstolba:
                add eax,ebx
                ret
 
-bcopy:
-               ; Do something here
-
                ; Set up registers as for a "Read", and compares against disk size
 setup_regs:
                call chstolba
@@ -219,6 +216,7 @@ setup_regs:
                add esi,[DiskBuf]
                cmp ebx,[DiskSize]
                jae .overrun
+               shr ecx,SECTORSIZE_LG2-1
                ret
 
 .overrun:      pop ax                  ; Drop return address
@@ -241,7 +239,7 @@ int15_e820:
                mov di,cs
                shr di,4
                add edi,E820Buf
-               mov ecx,24/4
+               mov ecx,24/2
                call bcopy
                add ebx, byte 12
                pop edi
@@ -285,7 +283,7 @@ Int15Start:
                cmp ah,88h
                je int15_88
 oldint15:      pop bp
-               jmp far [OldInt15]
+               jmp far [cs:OldInt15]
                
 int15_e801:
                mov ax,[cs:Mem1MB]
@@ -305,6 +303,58 @@ int15_88:
                mov ax,[cs:MemInt1588]
                jmp short int15_success
 
+;
+; Routine to copy in/out of high memory
+; esi = linear source address
+; edi = linear target address
+; ecx = 16-bit word count 
+;
+; Assumes cs = ds = es
+;
+bcopy:
+               push eax
+               push ebx
+               push edx
+               push ebp
+               push esi
+               push edi
+.copy_loop:
+               push ecx
+               cmp ecx,8000h
+               jna .safe_size
+               mov ecx,8000h
+.safe_size:
+               push ecx
+               mov eax, esi
+               mov [Mover_src1], si
+               shr eax, 16
+               mov [Mover_src1+2], al
+               mov [Mover_src2], ah
+               mov eax, edi
+               mov [Mover_dst1], di
+               shr eax, 16
+               mov [Mover_dst1+2], al
+               mov [Mover_dst2], ah
+               mov si,Mover
+               mov ah, 87h
+               int 15h
+               pop eax
+               pop ecx
+               pop edi
+               pop esi
+               jc .error
+               lea esi,[esi+2*eax]
+               lea edi,[edi+2*eax]
+               sub ecx, eax
+               jnz .copy_loop
+               ; CF = 0
+.error:
+               pop ebp
+               pop edx
+               pop ebx
+               pop eax
+               ret
+
                section .data
 Int13Funcs     dw Reset                ; 00h - RESET
                dw GetStatus            ; 01h - GET STATUS
@@ -348,6 +398,18 @@ Mem1MB             dd 0                    ; 1MB-16MB memory amount (1K)
 Mem16MB                dd 0                    ; 16MB-4G memory amount (64K)
 MemInt1588     dw 0                    ; 1MB-65MB memory amount (1K)
 
+               alignb 8, db 0
+Mover          dd 0, 0, 0, 0           ; Must be zero
+               dw 0ffffh               ; 64 K segment size
+Mover_src1:    db 0, 0, 0              ; Low 24 bits of source addy
+               db 93h                  ; Access rights
+               db 00h                  ; Extended access rights
+Mover_src2:    db 0                    ; High 8 bits of source addy
+Mover_dst1:    db 0, 0, 0              ; Low 24 bits of target addy
+               db 93h                  ; Access rights
+               db 00h                  ; Extended access rights
+Mover_dst2:    db 0                    ; High 8 bits of source addy
+
                section .bss
 OldInt13       resd 1                  ; INT 13h in chain
 OldInt15       resd 1                  ; INT 15h in chain