Reorganize memory slightly; split .bss into .bss and .earlybss and

move its base down to 0800h; relocate pxelinux since it needs
copious amounts of bss.

diff --git a/bcopy32.inc b/bcopy32.inc
index 3bd2ca9..7b70780 100644 (file)
--- a/bcopy32.inc
+++ b/bcopy32.inc
@@ -383,6 +383,9 @@ try_wbinvd:
 ; necessary code into the trackbuf area before doing the copy,
 ; and do adjustments to anything except BSS area references.
 ;
+; NOTE: Since PXELINUX relocates itself, put all these
+; references in the ".earlybss" segment.
+;
 ; After performing the copy, this routine resets the stack and
 ; jumps to 0:7c00.
 ;
@@ -393,7 +396,7 @@ try_wbinvd:
 ;      ESI, EDI, ECX   - same as bcopy
 ;      On stack        - initial state (fd, ad, ds, es, fs, gs)
 ;
-ADJUST         equ (__bcopy_start - $$) + 7C00h - BSS_START
+ADJUST         equ (__bcopy_start - $$) + TEXT_START - BSS_START
 
                align 2
 adjlist                dw bcopy_gdt.adj1 - ADJUST
@@ -450,7 +453,7 @@ bcopy_over_self:
                jmp 0:7c00h
 __bcopy_end:
 
-               section .bss
+               section .earlybss
 A20Test                resw 1                  ; Counter for testing status of A20
 A20Type                resw 1                  ; A20 type
 A20Tries       resb 1                  ; Times until giving up on A20

diff --git a/extlinux.asm b/extlinux.asm
index bb6215d..fcd3fc3 100644 (file)
--- a/extlinux.asm
+++ b/extlinux.asm
@@ -107,13 +107,14 @@ file_mode resw 1
 ;
 ; Memory below this point is reserved for the BIOS and the MBR
 ;
-BSS_START      equ 1000h
-               section .bss start=BSS_START
+BSS_START      equ 0800h
+               section .earlybss nobits start=BSS_START
 trackbufsize   equ 8192
 trackbuf       resb trackbufsize       ; Track buffer goes here
 getcbuf                resb trackbufsize
-               ; ends at 5000h
+               ; ends at 4800h
 
+               section .bss nobits align=256 follows=.earlybss
 SuperBlock     resb 1024               ; ext2 superblock
 SuperInfo      resq 16                 ; DOS superblock expanded
 ClustSize      resd 1                  ; Bytes/cluster ("block")
@@ -141,7 +142,8 @@ xbs_vgatmpbuf       equ 2*trackbufsize
 
 
                section .text
-                org 7C00h
+TEXT_START     equ 7C00h
+                org TEXT_START
 ;
 ; Some of the things that have to be saved very early are saved
 ; "close" to the initial stack pointer offset, in order to

diff --git a/isolinux.asm b/isolinux.asm
index 78e642a..3ba8297 100644 (file)
--- a/isolinux.asm
+++ b/isolinux.asm
@@ -103,13 +103,14 @@ dir_clust resd 1                  ; Length in clusters
 ;
 ; Memory below this point is reserved for the BIOS and the MBR
 ;
-BSS_START      equ 1000h
-               section .bss start=BSS_START
+BSS_START      equ 0800h
+               section .earlybss nobits start=BSS_START
 trackbufsize   equ 8192
 trackbuf       resb trackbufsize       ; Track buffer goes here
 getcbuf                resb trackbufsize
-;              ends at 5000h
+;              ends at 4800h
 
+               section .bss nobits align=256 follows=.earlybss
                alignb 4
 ISOFileName    resb 64                 ; ISO filename canonicalization buffer
 ISOFileNameEnd equ $
@@ -140,7 +141,8 @@ xbs_vgabuf  equ trackbufsize
 xbs_vgatmpbuf  equ 2*trackbufsize
 
                section .text
-                org 7C00h
+TEXT_START     equ 7C00h
+                org TEXT_START
 ;;
 ;; Primary entry point.  Because BIOSes are buggy, we only load the first
 ;; CD-ROM sector (2K) of the file, so the number one priority is actually

diff --git a/ldlinux.asm b/ldlinux.asm
index badbf76..2a5dfcc 100644 (file)
--- a/ldlinux.asm
+++ b/ldlinux.asm
@@ -109,13 +109,14 @@ file_left resd 1                  ; Number of sectors left
 ;
 ; Memory below this point is reserved for the BIOS and the MBR
 ;
-BSS_START      equ 1000h
-               section .bss start=BSS_START
+BSS_START      equ 0800h
+               section .earlybss nobits start=BSS_START
 trackbufsize   equ 8192
 trackbuf       resb trackbufsize       ; Track buffer goes here
 getcbuf                resb trackbufsize
-               ; ends at 5000h
+               ; ends at 4800h
 
+               section .bss nobits align=256 follows=.earlybss
                alignb 8
 
                ; Expanded superblock
@@ -151,7 +152,8 @@ xbs_vgatmpbuf       equ 2*trackbufsize
 
 
                section .text
-                org 7C00h
+TEXT_START     equ 7C00h
+                org TEXT_START
 ;
 ; Some of the things that have to be saved very early are saved
 ; "close" to the initial stack pointer offset, in order to

diff --git a/pxelinux.asm b/pxelinux.asm
index 329c7f8..2b7819b 100644 (file)
--- a/pxelinux.asm
+++ b/pxelinux.asm
@@ -175,18 +175,19 @@ tftp_pktbuf       resw 1                  ; Packet buffer offset
 ;
 ; Memory below this point is reserved for the BIOS and the MBR
 ;
-BSS_START      equ 1000h
-               section .bss start=BSS_START
+BSS_START      equ 0800h
+               section .earlybss nobits start=BSS_START
 trackbufsize   equ 8192
 trackbuf       resb trackbufsize       ; Track buffer goes here
 getcbuf                resb trackbufsize
-               ; ends at 5000h
+               ; ends at 4800h
 
-; Warning here: RBFG build 22 randomly overwrites memory location
-; [0x5680,0x576c), possibly more.  It seems that it gets confused and
-; screws up the pointer to its own internal packet buffer and starts
-; writing a received ARP packet into low memory.
-RBFB_brainfuck resb 800h
+               ; Put some large buffers here, before RBFG_brainfuck,
+               ; where we can still carefully control the address
+               ; assignments...
+
+               alignb open_file_t_size
+Files          resb MAX_OPEN*open_file_t_size
 
                alignb FILENAME_MAX
 BootFile       resb 256                ; Boot file from DHCP packet
@@ -195,6 +196,14 @@ ConfigName resb 256-4              ; Configuration file from DHCP option
 PathPrefix     resb 256                ; Path prefix derived from boot file
 DotQuadBuf     resb 16                 ; Buffer for dotted-quad IP address
 IPOption       resb 80                 ; ip= option buffer
+
+; Warning here: RBFG build 22 randomly overwrites memory location
+; [0x5680,0x576c), possibly more.  It seems that it gets confused and
+; screws up the pointer to its own internal packet buffer and starts
+; writing a received ARP packet into low memory.
+RBFG_brainfuck resb 0E00h
+
+               section .bss nobits align=256 follows=.earlybss
                alignb 4
 InitStack      resd 1                  ; Pointer to reset stack
 RebootTime     resd 1                  ; Reboot timeout, if set by option
@@ -223,9 +232,6 @@ pxe_unload_stack_pkt:
 .reserved:     resw 10                 ; Reserved
 pxe_unload_stack_pkt_len       equ $-pxe_unload_stack_pkt
 
-               alignb open_file_t_size
-Files          resb MAX_OPEN*open_file_t_size
-
                alignb 16
                ; BOOTP/DHCP packet buffer
 
@@ -245,7 +251,12 @@ xbs_vgabuf equ trackbufsize
 xbs_vgatmpbuf  equ 2*trackbufsize
 
                section .text
-                org 7C00h
+               ;
+               ; PXELINUX needs more BSS than the other derivatives;
+               ; therefore we relocate it from 7C00h on startup
+               ;
+TEXT_START     equ 9000h
+                org TEXT_START
 StackBuf       equ $-44                ; Base of stack if we use our own
 
 ;
@@ -253,8 +264,6 @@ StackBuf    equ $-44                ; Base of stack if we use our own
 ;
 bootsec                equ $
 _start:
-               jmp 0:_start1           ; Canonicalize address
-_start1:
                pushfd                  ; Paranoia... in case of return to PXE
                pushad                  ; ... save as much state as possible
                push ds
@@ -262,6 +271,15 @@ _start1:
                push fs
                push gs
 
+               mov si,ldlinux_end-(TEXT_START-7C00h)-4
+               mov di,ldlinux_end-4
+               mov cx,ldlinux_end-TEXT_START
+               shr cx,2
+               std                     ; Overlapping areas, copy backwards
+               rep movsb
+
+               jmp 0:_start1           ; Canonicalize address
+_start1:
                mov bp,sp
                les bx,[bp+48]          ; ES:BX -> !PXE or PXENV+ structure
 
@@ -2283,6 +2301,7 @@ writestr  equ cwritestr
 %include "highmem.inc"         ; High memory sizing
 %include "strcpy.inc"          ; strcpy()
 %include "rawcon.inc"          ; Console I/O w/o using the console functions
+%include "dnsresolv.inc"       ; DNS resolver
 
 ; -----------------------------------------------------------------------------
 ;  Begin data section