IBM's iSCSI Firmware Initiator checks the UNDIROMID pointer in the
!PXE structure that gets created by the UNDI loader. We didn't
previously fill this value in.
__from_data16 and __from_text16 now take a pointer to a
.data16/.text16 variable, and return the real-mode offset within the
appropriate segment. This matches the use case for every occurrence
of these macros, and prevents potential future bugs such as that fixed
in commit d51d80f. (The bug arose essentially because "&pointer" is
still syntactically valid.)
This allows pxelinux to execute arbitrary gPXE commands. This is
remarkably unsafe (not least because some of the commands will assume
full ownership of memory and do nasty things like edit the e820 map
underneath the calling pxelinux), but it does allow access to the
"sanboot" command.
defined in vsprintf.h. (This may change, since vsprintf.h is a
non-standard name, but for now it's the one to use.)
There should be no need to include vsprintf.h just for DBG() statements,
since include/compiler.h forces it in for a debug build anyway.
Updated PXE API dispatcher to use copy_{to,from}_user, and moved to
arch/i386 since the implementation is quite architecture-dependent.
(The individual PXE API calls can be largely
architecture-independent.)