MFC Loader Interpreter Coexistance: r337806, r337868, r337914, r337927,
r337989, r338052, r338064, r338407, r338418, r338474

r337806:
Create a loader for each interpreter for x86 BIOS and all EFI

Create loader_{4th,lua,simp}{,.efi}. All of these are installed by
default. Create LOADER_DEFAULT_INTERP to specify the default
interpreter when no other is specified. LOADER_INTERP is the current
interpreter language building. Turn building of lua on by default to
match 4th. simploader is a simplified loader build w/o any interpreter
language (but with a simple loader). This is the historic behavir you
got with WITHOUT_FORTH. Make a hard link to the default loader. This
has to be a hard link rather than the more desirable soft link because
older zfsboot blocks don't support symlinks.

r337868:
stand: Use -Oz/-Os for all loader/stand builds.

While we're not super size constrained, the x86 BIOS /boot/loader has
to be less than about 520k-530k to be reliable. The LUA loader is at
this size today. -Oz saves 15-20% on the size, keeping us safely small
enough (comparable to where we were with the 4th loader). This will
also help with sjg's work on bringing in bearssl, though we may again
be looking for space in the LUA loader.

Size table for clang 6.0.0:
default -O1 -Os -Oz
4th 442368 417792 389120 376832
lua 524288 479232 446464 430080

r337914:
Install links for loader.efi.

r337927:
Add ashldi3 and ashrdi3 to mips.

Now that we're using -Os, mips needs these routines.

r337989:
Copy the boot loader from the new location for the co-existing
loaders.

r338052:
libsa: Add lshrdi3.c for powerpc* and mips

r338064:
Turn back the clock just a little: make userboot.so always be 4th

Turns out there was a hidden dependency we hasn't counted upon. The
host load /boot/userboot.so to boot the VMs it runs. This means that
the change to lua meant suddently that nobody could run their older
VMs because LUA wasn't in 10.0, last month's HardenedBSD, 11.2 or
whatever. Even more than for the /boot/loader* binaries, we need a
good coexistance strategy for this. While that's being designed and
implemented, drop back to always 4th for userboot.so. This will fail
safe in all but the most extreme environments (but lua-only hacks
to .lua files won't be processes in VMs until we fix it).

r338407:
lualoader: Print error messages from command failures at the prompt

Previously lualoader would remain silent, rather than printing
command_errmsg or noting that a command had failed or was not found.

r338418:
userboot: handle guest interpreter mismatches more intelligently

The switch to lualoader creates a problem with userboot: the host is
inclined to build userboot with Lua, but the host userboot's interpreter
must match what's available on the guest. For almost all FreeBSD guests in
the wild, Lua is not yet available and a Lua-based userboot will fail.

This revision updates userboot protocol to version 5, which adds a
swap_interpreter callback to request a different interpreter, and tries to
determine the proper interpreter to be used based on how the guest
/boot/loader is compiled. This is still a bit of a guess, but it's likely
the best possible guess we can make in order to get it right. The
interpreter is now embedded in the resulting executable, so we can open
/boot/loader on the guest and hunt that down to derive the interpreter it
was built with.

Using -l with bhyveload will not allow an intepreter swap, even if the
loader specified happens to be a userboot with the wrong interpreter. We'll
simply complain about the mismatch and bail out.

For legacy guests without the interpreter marker, we assume they're 4th.
For new guests with the interpreter marker, we'll read it and swap over
to the proper interpreter if it doesn't match what the userboot we're using
was compiled with.

Both flavors of userboot are installed by default, userboot_4th.so and
userboot_lua.so. This fixes the build WITHOUT_FORTH as a coincidence, which
was broken by userboot being forced to 4th.

r338474:
Be a little conservative about when to force size optimizations.

Reports have come in that there's issue with powerpc and sparc64 since
we've switched to using -Oz / -Os. We don't strictly need them for
!x86, so be conservative about when we enable them.

MFC GELI Loader Improvements: r336252, r336254, r336256, r336354,
r336532-r336534, r336537, r336626, r337326, r337349, r341071, r341160,
r341420, r341473, r341651, r342793

Note that this MFC contains some seemingly unrelated zfsloader bits -- this
was needed in order to pull in some later fixes for GELI hand-off w/ ZFS
bits included.

r336252:
Extend loader(8) geli support to all architectures and all disk-like devices.

This moves the bulk of the geli support from lib386/biosdisk.c into a new
geli/gelidev.c which implements a devsw-type device whose dv_strategy()
function handles geli decryption. Support for all arches comes from moving
the taste-and-attach code to the devopen() function in libsa.

After opening any DEVT_DISK device, devopen() calls the new function
geli_probe_and_attach(), which will "attach" the geli code to the open_file
struct by creating a geli_devdesc instance to replace the disk_devdesc
instance in the open_file. That routes all IO for the device through the
geli code.

A new public geli_add_key() function is added, to allow arch/vendor-specific
code to add keys obtained from custom hardware or other sources.

With these changes, geli support will be compiled into all variations of
loader(8) on all arches because the default is WITH_LOADER_GELI.

r336254:
Use if rather than case for a simple boolean. gcc thinks blks is
undefined sometimes with the case, but enc is always 0 or 1, so
and if / else is better anyway.

r336256:
Fix glitched indentation (and rewrap as needed due to deeper indent).
No functional changes.

r336354:
zfsboot: fix build with WITHOUT_LOADER_GELI

r336532:
Collapse zfsloader functionality back down into loader.

We no longer really need a separate zfsloader. It was useful when we
were first supporting ZFS and had limited ability to properly boot off
of ZFS without the special boot loader. Now that the boot loader has
matured, go the way loader.efi pioneered and just build one
binary. Change the name of the loader to load in the secondary boot
blocks to be just /boot/loader. Provide a symbolic link from zfsloader
to loader so people who have not upgraded their boot blocks are not
affected. This has the happy benefit of making coexistence easier as
well (fewer binaries in the matrix).

r336533:
Eliminate zfsloader man page.

Remove all cross references to zfsloader.8 and /boot/zfsloader.
Move ZFS specific info into loader.8.

r336534:
NM and OBJCOPY are already defined for all builds. There's no need to
conditionally define them here.

r336537:
Mention zfsloader being folded into loader in UPDATING.

r336626:
Older zfs boot blocks don't support symlinks. install the link to
zfsloader as a hard link. While newer ones do, the whole point of the
link was to transition to the new world order smoothly. A hard link is
less flexible, but it works and will result in fewer bumps. Adjust
UPDATING entry to match.

r337326:
loader: biosdisk.c has leftover geli header.

A small cleanup, remove unneeded #include.

r337349:
zfsboot: Fix startup crash

On a FreeNAS mini XL, with geli encrypted drives the loader crashed in
geli_read().

When we iterate over the list of disks and allocate the zfsdsk structures we
don’t zero out the gdev pointer. In one case that resulted in geli_read()
(called on the bogus pointer) dividing by zero.

Use calloc() to ensure the zfsdsk structure is always zeroed, so the pointer is
initialised to NULL. As a side benefit it gets rid of one #ifdef
LOADER_GELI_SUPPORT.

r341071:
Restore the ability to override the disk unit/partition at the boot: prompt
in gptboot.

When arch-independent geli support was added, a new static 'gdsk' struct
was added, but there was still a static 'dsk' struct, and when you typed
in an alternate disk/partition, the string was parsed into that struct,
which was then never used for anything. Now the string gets parsed into
gdsk.dsk, the struct that's actually used.

r341160:
Add comments describing the bootargs handoff between loader(8) and gptboot
or zfsboot, when loader(8) is the BTX loader. No functional changes.

r341420:
Eliminate duplicated code and struct member definitions in the handoff
of args data between gptboot/zfsboot and loader(8).

Despite what seems like a lot of changes here, there are no actual
changes in behavior, or in the data layout in the structures involved.
This is just eliminating identical code pasted into multiple locations.

In detail, the changes are...

- Move struct zfs_boot_args definition from libsa/zfs/libzfs.h to
i386/common/bootargs.h because it is specific to x86 booting and the
handoff between zfsboot and loader, and has no relation to the zfs
library code in general.

- The geli_boot_args and zfs_boot_args structs both contain an identical
set of member variables containing geli information. Extract this out
to a new geli_boot_data struct, and embed it in the arg-passing structs.

- Provide new routines geli_import_boot_data() and geli_export_boot_data()
that can be shared between gptboot, zfsboot, and loader instead of
pasting identical code into several different .c files.

- Remove some checks for a NULL pointer that can never be true because the
pointer being tested was set using pointer math (kargs + 1) and that can
never result in NULL in this code.

r341473:
Fix args cross-threading between gptboot(8) and loader(8) with zfs support.

When loader(8) is built with zfs support enabled, it assumes that any extarg
data present is a zfs_boot_args struct, but if the first-stage loader was
gptboot(8) the extarg data is actually a geli_boot_args struct. Luckily,
zfsboot(8) and gptzfsboot(8) have always passed KARGS_FLAGS_ZFS along with
KARGS_FLAGS_EXTARG, so we can use KARGS_FLAGS_ZFS to decide whether the
extarg data is a zfs_boot_args struct.

To avoid similar problems in the future, gptboot(8) now passes a new
KARGS_FLAGS_GELI to indicate that extarg data is geli_boot_args. In
loader(8), if the neither KARGS_FLAGS_ZFS nor KARGS_FLAGS_GELI is set but
extarg data is present (which will be the case for gptboot compiled before
this change), we now check for the known size of the geli_boot_args struct
passed by the older versions of gptboot as a way of confirming what type of
extarg data is present.

In a semi-related tidying up, since loader's main() has already decided
what type of extarg data is present and set the global 'zargs' var
accordingly, don't repeat the check in extract_currdev, just check whether
zargs is NULL or not.

r341651:
Don't reference zfs-specific variables if LOADER_ZFS_SUPPORT is undefined
because the variables will be undefined too.

r342793:
MK_ZFS -> {MK_ZFS|MK_LOADER_ZFS}, this is so we can diable userland / kernel
ZFS but keep the boot-loaders when using ZoL port.

Relnotes: yes (GELI support extended)
Relnotes: yes (zfsloader has been collapsed into loader and may be
removed after boot blocks have been updated)

MFC r332084

Add isoboot(8) for booting BIOS systems from HDDs containing ISO images.

This is part of a project for adding the ability to create hybrid CD/USB boot
images. In the BIOS case when booting from something that isn't a CD we need
some extra boot code to actually find our next stage (loader) within an
ISO9660 filesystem. This code will reside in a GPT partition (similar to
gptboot(8) from which it is derived) and looks for /boot/loader in an
ISO9660 filesystem on the image.

Sponsored by: iXsystems, Inc.

MFC r330249-r330250

r330249:
stand: Makefile SUBDIR cleanup

Use SUBDIR.${MK_*} where appropriate. r330248 eliminated most of the
offenders, sweep the rest under the rug.

Differential Revision: https://reviews.freebsd.org/D14545

r330250:
stand: Fix build after r330249

One does not simply convert to SUBDIR.yes in stand without making everything
else in the affected files SUBDIR.yes -- there are better ways to do this.

MFC r330004: Add NO_OBJ to those directories that don't make anything.

For directories that don't many anything, add NO_OBJ=t just before we
include bsd.init.mk. This prevents them from creating an OBJ
directory. In addition, prevent defs.mk from creating the machine
related links in these cases. They aren't needed and break, at least
on stable, the read-only src tree build.

PR: 226074

MFC r325834,r325997,326502: Move sys/boot to stand/

This is effectively a direct commit to stable/11, due to differences between
stable/11 and head. Changes to DTS in sys/boot/fdt/dts were often
accompanied by kernel changes. Many of these were also risc-v updates that
likely had many more dependencies to MFC.

Because of this, sys/boot/fdt/dts remains as-is while everything else in
sys/boot relocates to stand/.

r325834: Move sys/boot to stand. Fix all references to new location

r325997: Remove empty directories.

r326502: Document the sys/boot -> stand move in hier.7 and the top-level README.

MFC Loader Fixes 2017q4p6: r324649,r324650,r324651,r324652,r324653,r324654,
r324700,r324702,r324709,r324717,r324719,r324841,r324842,r324843,r324845,
r324850,r324876,r324877,r324878,r324879,r324880,r324881,r324883,r324980,
r324981,r324982,r324995,r325014,r325093,r325094,r325114,r325170,r325171,
r325172,r325173,r325174,r325175,r325176,r325248,r325286,r325310,r325332,
r325338,r325339,r325376,r325377,r325379,r325380,r325382,r325478,r325479,
r325480,r325482,r325483,r325484,r325485,r325556,r325641,r325681,r325685,
r325686,r325687,r325688,r325689,r325690,r325691,r325692,r325693,r325694,
r325743,r325744,r325748,r325775,r325779,r325780

r324649: Move common/Makefile.inc to sys/boot/loader.mk.

r324650: tweak style

r324651: create defs.mk for common definitions

r324652: Move all the ficl common code into ficl.mk

r324653: LOADER_foo_SUPPORTED

r324654: Explicitly inlcude SYSDIR in the include path

r324700: loader: initialize dv_cleanup in md.c to eliminate clang warning

r324702: We need to include disk.o in libuboot.a when we're building with
support for disk access.

r324709: Revert "Unify boot1 with loader" change r324646

r324717: libsa/ip.c: misplaced comment, ip_v is half char, not ip_p

r324719: libsa/ip: stop read loop on bad fragments

r324841: Use BOOTDIR more consistently in defs.mk rather than repeat
sys/boot.

r324842: Introduce BOOTOBJ: The top level object directory for the boot tree

r324843: Stopgap fix to the mistmatch between LOADER_GELI_SUPPORT and
LOADER_NO_GELI_SUPPORT.

r324845: Use BOOTOBJ and BOOTDIR to find geli includes and libraries.

r324850: Define LIBSA32 to LIBSA on i386 to fix build.

r324876: Move fdt and uboot defines into common uboot.mk.

r324877: End source directories with SRC rather than a hodgepodge of names

r324878: Make at91 boot loader compile again.

r324879: Prefer SRCTOP paths for bits we're grabbing from libc.

r324880: Use BOOTSRC here.

r324881: Use SYSDIR instead of ${.CURDIR}/../..<etc>/sys.

r324883: Use preferred defined paths, rather than relative paths in fdt.

r324980: Use BOOTDIR consistently.

r324981: Move BINDIR definition to defs.mk, and override where it isn't
/boot

r324982: Remove sys/boot/arm/at91 and ixp425

r324995: loader.efi: Make framebuffer commands available for arm64

r325014: Add a 'place holder' arm struct efi_fb until a real one comes

r325093: Define new EFI variables

r325094: Cleanup non-arch Makefiles

r325114: Use defs.mk defins in most MD code

r325170: Use defs.mk values for userboot

r325171: Use defs.mk name and prefer bsd.init.mk

r325172: Remove the -nostdlib stuff I added. Instead, fix LDFLAGS to be
honored correctly with the new Makefile.inc include order.

r325173: We don't need to build a special ficl for userboot.

r325174: Minor cleanup

r325175: For amd64, compile both zfs and zfs32 libraries.

r325176: Actually add zfs32/Makefile

r325248: loader ptblread() is broken with >512B sectors

r325286: efipart_strategy is using wrong offset with >512B sectors

r325310: zfs.c:vdev_read() needs to be careful about large sectors

r325332: loader: re-enable gzip support for x86

r325338: loader: fix BOOTSRC -> BOOTOBJ in a library path

r325339: This used to have bzip2 support too.

r325376: WIP: centralize machine links

r325377: mostly libsa

r325379: Revert "mostly libsa"

r325380: Revert "WIP: centralize machine links"

r325382: Cleanup stray libstand names to be libsa names.

r325478: Powerpc is a 32-bit boot loader.

r325479: Define LIBFICL32 to be libficl.a on i386 and libficl32.a on amd64.

r325480: Use DO32 for all the places that we need to flag we're building a
32-bit version of a library.

r325482: Move machine and other link creation to defs.mk

r325483: MACHINE can never be powerpc64, so cleanup code that thinks it can.

r325484: Prefer bsd.init.mk to src.opts.mk

r325485: Centralize all 32-bit builds on 64-bit platform stuff.

r325556: loader: set options before including bsd.init.mk

r325641: loader.efi: efi_devpath_is_prefix should return bool

r325681: boot1: avoid using NULL device path

r325685: libsa32 isn't needed for i386. It's already a 32-bit platform.

r325686: Simplify this if to a direct assignment.

r325687: Remove all the empty help files from the powerpc build.

r325688: FDT support doesn't make sense for ps3, remove it.

r325689: Remove LOADER_FDT_SUPPORT as a Makefile variable.

r325690: Remove LOADER_ZFS_SUPPORT as a Makefile variable

r325691: Remove useless PNP define here.

r325692: Replace LOADER_FIREWIRE_SUPPORT variable

r325693: Move LOADER_{NO,}_GELI_SUPPORT to MK_LOADER_GELI

r325694: Install the 4th files in sys/boot/forth instead of each loader

r325743: Make sure the proper loader.rc gets installed.

r325744: boot1: also check for NULL device

r325748: Use proper include file.

r325775: Add loader.conf to the list of files that are MD.

r325779: Add /boot/dts to the list of default modules.

r325780: Don't add /boot/dt*s* but /boot/dt*b*. Stupid think-o.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Restore kgzldr on i386 only

I previously disconnected kgzdr based on a misunderstanding.

I'd still like to transition to supporting only the loader(8)-based
boot path for handling compressed kernels, but that can follow the
standard deprecation procedure.

This reverts r291113.

Requested by: dteske

Disconnect unused kgzldr from sys/boot/i386

Sponsored by: The FreeBSD Foundation

Use src.opts.mk in preference to bsd.own.mk except where we need stuff
from the latter.

Don't build zfsboot, gptzfsboot, and zfsloader if WITHOUT_ZFS is enabled.

MFC after: 1 week

Create a seperate ZFS enabled loader.

This adds zfsloader which will be called by zfsboot/gptzfsboot code rather
than the tradional loader. This eliminates the need to set the
LOADER_ZFS_SUPPORT variable in order to get a ZFS enabled loader.

Note however, that you must reinstall your bootcode (zfsboot/gptzfsboot)
in order for the boot process to use the new loader.

New installations will no longer be required to build a ZFS enabled
loader for a working ZFS boot system. Installing zfsboot/gptzfsboot is
sufficient for acknowledging the use of CDDL code and therefore the ZFS
enabled loader.

Based on a previous patch from jhb@

Reviewed by: jhb@
MFC after: 2 weeks

Fix amd64 build and re-enable gptzfsboot.

Disconnect gptzfsboot from the build until dfr@ gets his act together.

Add a GPT-aware variant of zfsboot which should be used in a similar manner
to gptboot, i.e. installed in a freebsd-boot partition using /sbin/gpart or
/sbin/gpt.

Tweak the /boot/loader ZFS support so that it can find ZFS pools that are
contained in GPT partitions.

Update ZFS from version 6 to 13 and bring some FreeBSD-specific changes.

This bring huge amount of changes, I'll enumerate only user-visible changes:

- Delegated Administration

Allows regular users to perform ZFS operations, like file system
creation, snapshot creation, etc.

- L2ARC

Level 2 cache for ZFS - allows to use additional disks for cache.
Huge performance improvements mostly for random read of mostly
static content.

- slog

Allow to use additional disks for ZFS Intent Log to speed up
operations like fsync(2).

- vfs.zfs.super_owner

Allows regular users to perform privileged operations on files stored
on ZFS file systems owned by him. Very careful with this one.

- chflags(2)

Not all the flags are supported. This still needs work.

- ZFSBoot

Support to boot off of ZFS pool. Not finished, AFAIK.

Submitted by: dfr

- Snapshot properties

- New failure modes

Before if write requested failed, system paniced. Now one
can select from one of three failure modes:
- panic - panic on write error
- wait - wait for disk to reappear
- continue - serve read requests if possible, block write requests

- Refquota, refreservation properties

Just quota and reservation properties, but don't count space consumed
by children file systems, clones and snapshots.

- Sparse volumes

ZVOLs that don't reserve space in the pool.

- External attributes

Compatible with extattr(2).

- NFSv4-ACLs

Not sure about the status, might not be complete yet.

Submitted by: trasz

- Creation-time properties

- Regression tests for zpool(8) command.

Obtained from: OpenSolaris

First cut at support for booting a GPT labeled disk via the BIOS bootstrap
on i386 and amd64 machines. The overall process is that /boot/pmbr lives
in the PMBR (similar to /boot/mbr for MBR disks) and is responsible for
locating and loading /boot/gptboot. /boot/gptboot is similar to /boot/boot
except that it groks GPT rather than MBR + bsdlabel. Unlike /boot/boot,
/boot/gptboot lives in its own dedicated GPT partition with a new
"FreeBSD boot" type. This partition does not have a fixed size in that
/boot/pmbr will load the entire partition into the lower 640k. However,
it is limited in that it can only be 545k. That's still a lot better than
the current 7.5k limit for boot2 on MBR. gptboot mostly acts just like
boot2 in that it reads /boot.config and loads up /boot/loader. Some more
details:
- Include uuid_equal() and uuid_is_nil() in libstand.
- Add a new 'boot' command to gpt(8) which makes a GPT disk bootable using
/boot/pmbr and /boot/gptboot. Note that the disk must have some free
space for the boot partition.
- This required exposing the backend of the 'add' function as a
gpt_add_part() function to the rest of gpt(8). 'boot' uses this to
create a boot partition if needed.
- Don't cripple cgbase() in the UFS boot code for /boot/gptboot so that
it can handle a filesystem > 1.5 TB.
- /boot/gptboot has a simple loader (gptldr) that doesn't do any I/O
unlike boot1 since /boot/pmbr loads all of gptboot up front. The
C portion of gptboot (gptboot.c) has been repocopied from boot2.c.
The primary changes are to parse the GPT to find a root filesystem
and to use 64-bit disk addresses. Currently gptboot assumes that the
first UFS partition on the disk is the / filesystem, but this algorithm
will likely be improved in the future.
- Teach the biosdisk driver in /boot/loader to understand GPT tables.
GPT partitions are identified as 'disk0pX:' (e.g. disk0p2:) which is
similar to the /dev names the kernel uses (e.g. /dev/ad0p2).
- Add a new "freebsd-boot" alias to g_part() for the new boot UUID.

MFC after: 1 month
Discussed with: marcel (some things might still change, but am committing
what I have so far)

MFp4: add FireWire/dcons support in loader for i386/amd64.

It is disabled by default. You need to put
LOADER_FIREWIRE_SUPPORT=yes in /etc/make.conf
and rebuild loader to enable it.
(cd /sys/boot/i386 && make clean && make && make install)

You can find a short introduction of dcons at
http://wiki.freebsd.org/DebugWithDcons

Hook boot0sio to the build. Use 'boot0cfg -b /boot/boot0sio' to use.

RIP liloldr.
It is not complete (the LILO root= specification isn't passed to our
loader for instance), it has not been touched in over 2 years. Linux has
moved on to GRUB, so this is OBE now. If someone creeps up to work on it,
it could become a port.

Revert the part of Kirks UFS2 commit which added divdi3.c and moddi3.c
to libi386, this issue was resolved already in a cleaner way.

This commit adds basic support for the UFS2 filesystem. The UFS2
filesystem expands the inode to 256 bytes to make space for 64-bit
block pointers. It also adds a file-creation time field, an ability
to use jumbo blocks per inode to allow extent like pointer density,
and space for extended attributes (up to twice the filesystem block
size worth of attributes, e.g., on a 16K filesystem, there is space
for 32K of attributes). UFS2 fully supports and runs existing UFS1
filesystems. New filesystems built using newfs can be built in either
UFS1 or UFS2 format using the -O option. In this commit UFS1 is
the default format, so if you want to build UFS2 format filesystems,
you must specify -O 2. This default will be changed to UFS2 when
UFS2 proves itself to be stable. In this commit the boot code for
reading UFS2 filesystems is not compiled (see /sys/boot/common/ufsread.c)
as there is insufficient space in the boot block. Once the size of the
boot block is increased, this code can be defined.

Things to note: the definition of SBSIZE has changed to SBLOCKSIZE.
The header file <ufs/ufs/dinode.h> must be included before
<ufs/ffs/fs.h> so as to get the definitions of ufs2_daddr_t and
ufs_lbn_t.

Still TODO:
Verify that the first level bootstraps work for all the architectures.
Convert the utility ffsinfo to understand UFS2 and test growfs.
Add support for the extended attribute storage. Update soft updates
to ensure integrity of extended attribute storage. Switch the
current extended attribute interfaces to use the extended attribute
storage. Add the extent like functionality (framework is there,
but is currently never used).

Sponsored by: DARPA & NAI Labs.
Reviewed by: Poul-Henning Kamp <phk@freebsd.org>

Reconnect boot2. I'm sure I'll regret this though. :-)

Turn off boot2 -- it gained over 96 bytes dieting on the in-tree Gcc 3.1.

Use the new cdboot instead of cdldr.

Hook up liloldr

Mega i386 loader commit.
- Don't hard code 0x10000 as the entry point for the loader. Instead add
src/sys/boot/i386/Makefile.inc which defines a make variable with the
entry point for the loader. Move the loader's entry point up to
0x20000, which makes PXE happy.
- Don't try to use cpp to parse btxldr for the optional BTXLDR_VERBOSE,
instead use m4 to achieve this. Also, add a BTXLDR_VERBOSE knob in the
btxldr Makefile to turn this option on.
- Redo parts of cdldr's Makefile so that it now builds and installs cdboot
instead of having i386/loader/Makefile do that. Also, add in some more
variables to make the pxeldr Makefile almost identical and thus to ease
maintainability.
- Teach cdldr about the a.out format. Cdldr now parsers the a.out header
of the loader binary and relocates it based on that. The entry point of
the loader no longer has to be hardcoded into cdldr. Also, the boot
info table from mkisofs is no longer required to get a useful cdboot.
- Update the lsdev function for BIOS disks to parse other file systems
(such as DOS FAT) that we currently support. This is still buggy as
it assumes that a floppy with a DOS boot sector actually has a MBR and
parses it as such. I'll be fixing this in the future.
- The biggie: Add in support for booting off of PXE-enabled network
adapters. Currently, we use the TFTP API provided by the PXE BIOS.
Eventually we will switch to using the low-level NIC driver thus
allowing both TFTP and NFS to be used, but for now it's just TFTP.

Submitted by: ps, alfred
Testing by: Benno Rice <benno@netizen.com.au>

Add the new cdldr CD bootstrap loader. This patch includes the following:

- Fix btxldr to preserve a NULL bootinfo pointer when it copies the kernel
arguments.
- Add the cdldr bootstrap program. This program is tacked onto the
beginning of the standard 3rd stage boot loader (/boot/loader) to form
the CD boot loader (/boot/cdboot). When a CD is booted, the cdboot file
is copied into memory instead and executed. The cdldr stub emulates the
environment normally provided by boot2 and then starts the loader. This
booting method does not emulate a floppy drive, but boots directly off of
the CD. This should fix the problems some BIOS's have with emulating a
2.88 MB floppy image.
- Add support to the loader to recognize that it has been booted by cdldr
instead of boot2 and use a simpler method of extracting the BIOS boot
device.

$Id$ -> $FreeBSD$

Activate kgzldr.

Activate mbr.

Activate boot2.

Drop .MAKEFLAGS: hack.

Override for ELF.

Turn off the new /sys/boot stuff (except boot0) unless OBJFORMAT
is elf. (The BTX client must be ELF, though it is packaged as a.out
for compatibility.)

Build boot0 as well.

Initial integration of the i386 bootloader and BTX.

- Discard large amounts of BIOS-related code in favour of the more compact
BTX vm86 interface.
- Build the loader module as ELF, although the resulting object is a.out,
make gensetdefs 32/64-bit sensitive and use a single copy of it.
- Throw away installboot, as it's no longer required.
- Use direct bcopy operations in the i386_copy module, as BTX
maps the first 16M of memory. Check operations against the
detected size of actual memory.

This commit was generated by cvs2svn to compensate for changes in r38465,
which included commits to RCS files with non-trunk default branches.

This is the new unified bootstrap, sometimes known previously as the
'three-stage' bootstrap.
There are a number of caveats with the code in its current state:
- The i386 bootstrap only supports booting from a floppy.
- The kernel and kld do not yet know how to deal with the extended
information and module summary passed in.
- PnP-based autodetection and demand loading of modules is not implemented.
- i386 ELF kernel loading is not ready yet.
- The i386 bootstrap is loaded via an ugly blockmap.

On the alpha, both net- and disk-booting (SRM console machines only) is
supported. No blockmaps are used by this code.

Obtained from: Parts from the NetBSD/i386 standalone bootstrap.