MFC r366364:

Correct the documented size of kern.msgbufsize

The correct value is 96KB after r226090.

PR: 249971
Submitted by: johannes@jo-t.de

MFC r337321, r337435, r337707, r337740, r337834, r337836, r337968

r337321:
Make it possible for init to execute any executable, not just sh(1)
scripts. This means one should be able to eg rewrite their /etc/rc
in Python.

r337435:
Move description of init_shell, init_script, and init_chroot kenv
tunables from loader(8) to init(8), since it's init that actually
uses them. Add .Xrs at their old place.

r337707:
Move around text in loader(8), in particular stuff related to ZFS,
to restore the usual section order.

r337740:
Add init_exec kenv(1) variable, to make init(8) execute a file
after opening the console, replacing init as PID 1.

From the user point of view, it makes it possible to run eg the
shell as PID 1, using 'set init_exec=/bin/sh' at the loader(8)
prompt.

r337834:
Add SECURITY section to loader(8).

r337836:
Improve formatting.

r337968:
Consistently use NULL to terminate the argv; no functional changes.

Relnotes: yes (init_exec kenv(1) variable)

MFC r333662: Clarify that boot_mute / boot -m mutes kernel console only

Perhaps RB_MUTE could mute user startup (rc) output as well, but right
now it mutes only kernel console output, so make the documentation match
reality.

PR: 228193

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 r336919, r336924

r336919:
efirt: Add tunable to allow disabling EFI Runtime Services

Leading up to enabling EFIRT in GENERIC, allow runtime services to be
disabled with a new tunable: efi.rt_disabled. This makes it so that EFIRT
can be disabled easily in case we run into some buggy UEFI implementation
and fail to boot.

r336924:
Follow up to r336919 and r336921: s/efi.rt_disabled/efi.rt.disabled/

The latter matches the rest of the tree better [0]. The UPDATING entry has
been updated to reflect this, and the new tunable is now documented in
loader(8) [1].

Reported by: imp [0], Shawn Webb [1]

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.

MFC Loader Fixes 2017q4p5: r324557,r324558,r324559,r324646,r324647

r324557: Rename exit to efi_exit to avoid clashing with libsa exit
definition

r324558: Define prototype for exit and ensure references

r324559: Move panic back into libsa. It's documented in libstand(3) to
belong there.

r324646: Unify boot1 with loader.

r324647: Move orphaned man pages into new man directory from common.

Move orphaned man pages into new man directory from common. This helps
keep cleaer that common is just for the MI files for /boot/loader
programs.

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