Switch to consistent use of 64-bit sector pointers; this should enable
booting even for individual *partitions* larger than 2 TB.  In order
to not slow down the boot too much, switch the initial load from an
enumeration to an extent map.  This means the table gets larger (since
we have to assume the worst case), but it simplifies the Sector 1 code
(since we can push all the hard stuff into the installer), and will
speed up booting in the general case.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

The first sector ptr is in bs->NextSector not in the array in
the patch_area. And actually the ADV sectors counting is wrong for a
while ...

Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

A lot of modules are common to *all* the derivatives (as opposed to
just "most"); move those to common.inc.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Handle more than 32K worth of code for disk-based derivatives.  We do
this by allowing the sector pointers to overflow past sector 1; this
is OK because we limit a run to be based on only the pointers that we
have read so far.

XXX: This is implemented for EXTLINUX, but breaks SYSLINUX.  Need to
update (and unify!) the SYSLINUX installers to cope.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Rename the .text, .data and .bss sections to .text16, .data16 and
.bss16, in anticipation of being linked with compiler-generated 32-bit
code, which presumably would like to use the standard section names.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

The "write with verify" functionality in EDD is AL=01h or AL=02h
depending on EDD version, not AL=80h.  Since it is apparently
version-dependent, don't even try to do it; furthermore, some BIOSes
are known to reject a write with this feature requested no matter
what.  At some point we may want to explicitly read back to verify.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Add a new macro "alignz" to align with zero bytes; use to align inside
a data section (i.e. a progbits section which doesn't contain code.)

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

Fix numerous problems in the way we handled the ADV with CBIOS.  The
EBIOS code was largely correct, but the CBIOS code was just busted.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Move source files out of the root directory; the root is a mess and
has become virtually unmaintainable.  The Syslinux core now lives in
core/; the Linux and generic utilities has moved into utils/, and
copybs.com has moved into dos/; it had to go somewhere, and it seemed
as good a place as any.