diff options
Diffstat (limited to 'pxelinux.asm')
| -rw-r--r-- | pxelinux.asm | 115 |
1 files changed, 110 insertions, 5 deletions
diff --git a/pxelinux.asm b/pxelinux.asm index 4f5e806a..6df269e6 100644 --- a/pxelinux.asm +++ b/pxelinux.asm @@ -376,6 +376,7 @@ PktTimeout resw 1 ; Timeout for current packet KernelExtPtr resw 1 ; During search, final null pointer IPOptionLen resw 1 ; Length of IPOption LocalBootType resw 1 ; Local boot return code +RealBaseMem resw 1 ; Amount of DOS memory after freeing TextAttrBX equ $ TextAttribute resb 1 ; Text attribute for message file TextPage resb 1 ; Active display page @@ -476,7 +477,7 @@ _start1: ; Nothing there either. Last-ditch: scan memory call memory_scan_for_pxe_struct ; !PXE scan - jnc have_pxe + jnc near have_pxe call memory_scan_for_pxenv_struct ; PXENV+ scan jnc have_pxenv @@ -500,12 +501,12 @@ have_pxenv: mov ax,es les bx,[es:bx+28h] ; !PXE structure pointer cmp dword [es:bx],'!PXE' - je have_pxe + je near have_pxe ; Nope, !PXE structure missing despite API 2.1+, or at least ; the pointer is missing. Do a last-ditch attempt to find it. call memory_scan_for_pxe_struct - jnc have_pxe + jnc near have_pxe ; Otherwise, no dice, use PXENV+ structure mov bx,si @@ -518,6 +519,43 @@ old_api: ; Need to use a PXENV+ structure mov eax,[es:bx+0Ah] ; PXE RM API mov [PXENVEntry],eax + mov si,undi_data_msg ; *** + call writestr + mov ax,[es:bx+20h] + call writehex4 + call crlf + mov si,undi_data_len_msg + call writestr + mov ax,[es:bx+22h] + call writehex4 + call crlf + mov si,undi_code_msg + call writestr + mov ax,[es:bx+24h] + call writehex4 + call crlf + mov si,undi_code_len_msg + call writestr + mov ax,[es:bx+26h] + call writehex4 + call crlf + + ; Compute base memory size from PXENV+ structure + xor esi,esi + movzx eax,word [es:bx+20h] ; UNDI data seg + cmp ax,[es:bx+24h] ; UNDI code seg + ja .use_data + mov ax,[es:bx+24h] + mov si,[es:bx+26h] + jmp short .combine +.use_data: + mov si,[es:bx+22h] +.combine: + shl eax,4 + add eax,esi + shr eax,10 ; Convert to kilobytes + mov [RealBaseMem],ax + mov si,pxenventry_msg call writestr mov ax,[PXENVEntry+2] @@ -527,12 +565,48 @@ old_api: ; Need to use a PXENV+ structure mov ax,[PXENVEntry] call writehex4 call crlf - jmp short have_entrypoint + jmp near have_entrypoint have_pxe: mov eax,[es:bx+10h] mov [PXEEntry],eax + mov si,undi_data_msg ; *** + call writestr + mov eax,[es:bx+2Ah] + call writehex8 + call crlf + mov si,undi_data_len_msg + call writestr + mov ax,[es:bx+2Eh] + call writehex4 + call crlf + mov si,undi_code_msg + call writestr + mov ax,[es:bx+32h] + call writehex8 + call crlf + mov si,undi_code_len_msg + call writestr + mov ax,[es:bx+36h] + call writehex4 + call crlf + + ; Compute base memory size from !PXE structure + xor esi,esi + mov eax,[es:bx+2Ah] + cmp eax,[es:bx+32h] + ja .use_data + mov eax,[es:bx+32h] + mov si,[es:bx+36h] + jmp short .combine +.use_data: + mov si,[es:bx+2Eh] +.combine: + add eax,esi + shr eax,10 + mov [RealBaseMem],ax + mov si,pxeentry_msg call writestr mov ax,[PXEEntry+2] @@ -4161,7 +4235,8 @@ ack_packet: ; ; unload_pxe: ; -; This function unloads the PXE and UNDI stacks. +; This function unloads the PXE and UNDI stacks and unclaims +; the memory. ; unload_pxe: mov di,pxe_udp_close_pkt @@ -4173,7 +4248,32 @@ unload_pxe: mov di,pxe_unload_stack_pkt mov bx,PXENV_UNLOAD_STACK call far [PXENVEntry] + jc .cant_free + cmp word [pxe_unload_stack_pkt.status],byte PXENV_STATUS_SUCCESS + jne .cant_free + + mov ax,[RealBaseMem] + cmp ax,[BIOS_fbm] ; Sanity check + jna .cant_free + + ; Check that PXE actually unhooked the INT 1Ah chain + movzx ebx,word [4*0x1a] + movzx ecx,word [4*0x1a+2] + shl ecx,4 + add ebx,ecx + shr ebx,10 + cmp bx,ax ; Not in range + jae .ok + cmp bx,[BIOS_fbm] + jae .cant_free + +.ok: + mov [BIOS_fbm],ax ret + +.cant_free: + mov si,cant_free_msg + jmp writestr ; ; gendotquad @@ -4786,6 +4886,11 @@ pxeentry_msg db 'PXE entry point found (we hope) at ', 0 pxenventry_msg db 'PXENV entry point found (we hope) at ', 0 trymempxe_msg db 'Scanning memory for !PXE structure... ', 0 trymempxenv_msg db 'Scanning memory for PXENV+ structure... ', 0 +undi_data_msg db 'UNDI data segment at: ',0 +undi_data_len_msg db 'UNDI data segment size: ',0 +undi_code_msg db 'UNDI code segment at: ',0 +undi_code_len_msg db 'UNDI code segment size: ',0 +cant_free_msg db 'Failed to free base memory, sorry...', CR, LF, 0 notfound_msg db 'not found', CR, LF, 0 myipaddr_msg db 'My IP address seems to be ',0 tftpprefix_msg db 'TFTP prefix: ', 0 |