This is the core portion of the async I/O interface.

Removed data_in_len and data_out_len from ata_command structure; the
lengths are implied by the sector count and the presence of the data_in
or data_out pointers.

Changed AoE code to use subcommands by default, and made aoe_issue()
nonblocking (with completion via async_wait()).

these timer objects in AoE and UDP protocols (where there is no underlying
retransmission mechanism) without requiring each protocol to implement its
own individual retry logic.  Eventually, we should be able to use the same
timer code for TCP retransmissions as well.

  Cannot yet handle reads of more than two sectors

  No retransmission

  No way to find out a target's MAC address (this proof of concept uses
  broadcasts)

These limitations shall not last long!  :)

Increase code simplicity at the expense of around 64 bytes.

orders of magnitude.

generic three-wire serial device support for EEPROM access.

hardware that can't autopad).

used on RTL8139 cards).

worrying about its stack being destroyed during the Etherboot run.

need for a CONFIG_RELOCATE.

install() now calls relocate(), moves the protected-mode code to the new
location, and calls hide_etherboot().

Change semantics; relocate() now just finds a suitable location; it
doesn't actually perform the relocation itself.  Code in libprefix does
the copy in flat real mode.

order?

requiring each caller to decide how many entries it wants to permit.

REAL_CODE() don't need it.

int13_boot() now does its own segment register save and restore, ready
for the removal of segment register restoration from the libkir
generic code.

Ignore carry flag for INT 15,88; the Ralf Brown interrupt list says
that CF is unreliable for this call.

completely.

the only one we actually use).  This allows REAL_EXEC fragments to
contain proper references to constraints (e.g. "%w0"), rather than having
to force the use of specific registers.

Note that the "num_constraints" parameter is now completely obsolete, and
that we can probably reduce the syntax to something like
  __asm__ __volatile__ ( REAL_CODE ( "asm statements" )
                         : output constraints
                         : input constraints
                         : clobber );
which would look much more natural, and avoid the need to always specify
a clobber list.


Add userptr_t to libkir.h, to allow it to at least compile.

and creating a memory map that's easier to work with than the E820 map.

down to base memory, since it is now in the base-memory-resident
.text16 section).

usual __{text,data}16 trick work with arrays.  gcc seems to accept the
__asm__ ( asmlabel ) only after the [] of the array declaration, not
before.