Support "localboot" option for PXELINUX.

diff --git a/NEWS b/NEWS
index 791ceb5..a1659fd 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,8 @@ Changes in 1.53:
        * PXELINUX: Update the docs to outline how to work with the
          kano.org.uk pxe server daemon.  A more complete example
          setup still needs to be written.
+       * PXELINUX: Support new "localboot" option for "label"
+         sections.
 
 Changes in 1.52:
        * PXELINUX: Fix bugs introduced by new A20 code.  (SYSLINUX

diff --git a/TODO b/TODO
index 7de43ac..b8b7dfb 100644 (file)
--- a/TODO
+++ b/TODO
@@ -1,3 +1,4 @@
+- Clean up the command-line parsing.
 - Cleaned up documentation, with a real man page.
 - Support for clusters larger than 16K.  This would require changing
   a lot of the SYSLINUX internals so we can read partial clusters;
@@ -22,4 +23,3 @@
     4Ch           - Terminate program
 
   ... in addition to INT 20h (Terminate program), of course.
-- Create or point users to a better PXE boot daemon.

diff --git a/pxelinux.asm b/pxelinux.asm
index c447a1b..d7cb3f4 100644 (file)
--- a/pxelinux.asm
+++ b/pxelinux.asm
@@ -310,7 +310,6 @@ trackbufsize        equ $-trackbuf
 ;              trackbuf ends at 5000h
 
                 absolute 5000h          ; Here we keep our BSS stuff
-StackBuf       equ $                   ; Start the stack here (grow down - 4K)
 VKernelBuf:    resb vk_size            ; "Current" vkernel
                alignb 4
 AppendBuf       resb max_cmd_len+1     ; append=
@@ -392,7 +391,14 @@ packet_buf_size    equ $-packet_buf
 bootsec                equ $
 _start:
                jmp 0:_start1           ; Canonicalize address
-_start1:       
+_start1:
+               pushad                  ; Paranoia... in case of return to PXE
+               pushfd                  ; ... save as much state as possible
+               push ds
+               push es
+               push fs
+               push gs
+       
                mov bp,sp
                les bx,[bp+4]           ; Initial !PXE structure pointer
 
@@ -864,6 +870,8 @@ parse_config:
                je near pc_say
                cmp ax,'ip'                     ; IPappend
                je pc_ipappend
+               cmp ax,'lo'                     ; LOcalboot
+               je pc_localboot
                cmp al,'f'                      ; F-key
                jne parse_config
                jmp pc_fkey
@@ -904,8 +912,13 @@ pc_ipappend:       call getint                     ; "ipappend" command
 .vk:           mov [VKernelBuf+vk_ipappend],bl
                jmp short parse_config_2
 
+pc_localboot:  cmp word [VKernelCtr],byte 0    ; "localboot" command
+               je parse_config_2               ; ("label" section only)
+               mov [VKernelBuf+vk_rname], byte 0       ; Null kernel name
+               jmp short parse_config_2
+
 pc_kernel:     cmp word [VKernelCtr],byte 0    ; "kernel" command
-               je near parse_config            ; ("label" section only)
+               je parse_config_2               ; ("label" section only)
                mov di,trackbuf
                push di
                call getline
@@ -1302,7 +1315,7 @@ get_kernel:     mov byte [KernelName+FILENAME_MAX],0      ; Zero-terminate filename/e
                 mov di,KernelName              ; Search on disk
                 call searchdir
                pop bx
-                jnz kernel_good
+                jnz near kernel_good
                mov eax,[bx]                    ; Try a different extension
                mov si,[KernelExtPtr]
                mov [si],eax
@@ -1356,7 +1369,12 @@ vk_found:        popa
                mov al,[VKernelBuf+vk_ipappend]
                mov [IPAppend],al
                xor bx,bx                       ; Try only one version
-               jmp get_kernel
+
+               ; Is this a "localboot" pseudo-kernel?
+               cmp byte [VKernelBuf+vk_rname], 0
+               jne near get_kernel             ; No, it's real, go get it
+
+               jmp local_boot
 ;
 ; kernel_corrupt: Called if the kernel file does not seem healthy
 ;
@@ -2081,6 +2099,24 @@ is_bss_sector:
 .badness:      jmp short .badness
 
 ;
+; Boot to the local disk by returning the appropriate PXE magic
+;
+local_boot:
+               lss sp,[cs:Stack]               ; Restore stack pointer
+               pop ds                          ; Restore DS
+               mov si,localboot_msg
+               call writestr
+               ; Restore the environment we were called with
+               pop gs
+               pop fs
+               pop es
+               pop ds
+               popfd
+               popad
+               xor ax,ax                       ; Unload PXE and local boot
+               retf                            ; Return to PXE
+
+;
 ; 32-bit bcopy routine for real mode
 ;
 ; We enter protected mode, set up a flat 32-bit environment, run rep movsd
@@ -2467,8 +2503,7 @@ abort_load:
                 mov ds,ax
                 mov es,ax
                 cli
-                mov sp,StackBuf-2*3                    ; Reset stack
-                mov ss,ax                       ; Just in case...
+               lss sp,[cs:Stack]               ; Reset the stack
                 sti
                 call cwritestr                  ; Expects SI -> error msg
 al_ok:          jmp enter_command               ; Return to command prompt
@@ -2486,6 +2521,7 @@ ac_ret1:  ret
 kaboom:
                lss sp,[cs:Stack]
                pop ds
+               push ds
                sti
 .patch:                mov si,bailmsg
                call writestr           ; Returns with AL = 0
@@ -4024,6 +4060,7 @@ trymempxenv_msg   db 'Scanning memory for PXENV+ structure... ', 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
+localboot_msg  db 'Booting from local disk...', CR, LF, 0
 cmdline_msg    db 'Command line: ', CR, LF, 0
 ready_msg      db ' ready.', CR, LF, 0
 trying_msg     db 'Trying to load: ', 0
@@ -4052,7 +4089,6 @@ initrd_cmd_len    equ 7
                align 2, db 0
 
 keywd_table    db 'ap' ; append
-               db 'ip' ; ipappend
                db 'de' ; default
                db 'ti' ; timeout
                db 'fo' ; font
@@ -4074,6 +4110,9 @@ keywd_table       db 'ap' ; append
                db 'f8' ; F8
                db 'f9' ; F9
                db 'f0' ; F10
+               ; PXELINUX specific options...
+               db 'ip' ; ipappend
+               db 'lo' ; localboot
                dw 0
 ;
 ; Extensions to search for (in *forward* order).

diff --git a/syslinux.doc b/syslinux.doc
index 4f4f435..31572bf 100644 (file)
--- a/syslinux.doc
+++ b/syslinux.doc
@@ -154,6 +154,11 @@ LABEL label
         Append nothing.  APPEND with a single hyphen as argument in a
         LABEL section can be used to override a global APPEND.
 
+  LOCALBOOT flag_val
+       On PXELINUX, specifying "LOCALBOOT 1" instead of a "KERNEL"
+       option means invoking this particular label will cause a local
+       disk boot instead of booting a kernel.
+
 IMPLICIT flag_val
         If flag_val is 0, do not load a kernel image unless it has been
         explicitly named in a LABEL statement.  The default is 1.