arm64: Support BTI checking in most of the kernel

LLD has the -zbti-report=error argument to check if the BTI note is
present when linking. To allow for this to be used when linking the
kernel and modules:
- Add the BTI note to the remaining assembly files
- Mark ptrauth.c as protected by BTI
- Disable -zbti-report for vmm hypervisor switching code as it's not
used there.

The linux64 module doesn't build with the flag as it includes vdso code
that doesn't include the note.

Reviewed by: imp, kib, emaste
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D45466

arm64: fix free queue and reservation configuration for 16KB pages

Correctly configure the free page queues and the reservation size when
the base page size is 16KB. In particular, the reservation size was
less than the L2 Block size, making L2 promotions and mappings all but
impossible.

Reviewed by: markj
Tested by: gallatin
Differential Revision: https://reviews.freebsd.org/D42737

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

Remove "All Rights Reserved" from FreeBSD Foundation sys/ copyrights

These ones were unambiguous cases where the Foundation was the only
listed copyright holder (in the associated license block).

Sponsored by: The FreeBSD Foundation

Move the arm64 userspace access checks to macros

In the functions that copy between userspace and kernel space we check the
user space address is valid before performing the copy. These are mostly
identical within each type of function so create two macros to perform the
check.

Obtained from: CheriBSD
Sponsored by: Innovate UK

Remove direct user access from the arm64 copyinstr

These already use the load variant that simulates userspace access.
Remove the macros that enable normal loads and stores from userspace
as they are unneeded.

Sponsored by: Innovate UK

Rename assym.s to assym.inc

assym is only to be included by other .s files, and should never
actually be assembled by itself.

Reviewed by: imp, bdrewery (earlier)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D14180

In ARMv8.1 ARM has added a process state bit to disable access to userspace
from the kernel. Make use of this to restrict accessing userspace to just
the functions that explicitly handle crossing the user kernel boundary.

Reported by: kib
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D10371

Use the unprivileged variant of the load and store instructions most
places possible in the kernel. This forces these functions to fail if
userspace is unable to access a given memory location, even if it is in
the user memory range.

This will simplify adding Privileged Access Never support later.

MFC after: 1 week
Sponsored by: DARPA, AFRL

Allow vmparam.h to be included from assembly files on arm64.

Obtained from: ABT Systems Ltd
Sponsored by: The FreeBSD Foundation

arm64: Fixing user space boudary checking in copyinout.S

Big buffer size could cause integer overflow and as a result
attempt to copy beyond VM_USERMAX_ADDRESS.

Fixing copyinstr boundary checking where compared value has been
overwritten by accident when setting fault handler.

Submitted by: Dominik Ermel <der@semihalf.com>
Obtained from: Semihalf
Sponsored by: Cavium
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D5719

ARM64 copyinout improvements

The first of set of patches.
Use wider load/stores when aligned buffer is being copied.

In a simple test:
dd if=/dev/zero of=/dev/null bs=1M count=1024
the performance jumped from 410MB/s up to 3.6GB/s.

TODO:
- better handling of unaligned buffers (WiP)
- implement similar mechanism to bzero

Submitted by: Dominik Ermel <der@semihalf.com>
Obtained from: Semihalf
Sponsored by: Cavium
Reviewed by: kib, andrew, emaste
Differential Revision: https://reviews.freebsd.org/D5664

Add checks for kernel VA accesses to the copyin(9) and related
functions on arm64.

Reviewed by: andrew
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D3907

Rework copyinstr to:
* Fail when the length passed in is 0
* Remove an unneeded increment of the count on success
* Return ENAMETOOLONG when the input pointer is too long

Sponsored by: ABT Systems Ltd

Bring in the start of the arm64 kernel.

This is only the minimum set of files needed to boot in qemu. As such it is
missing a few things.

The bus_dma code is currently only stub functions with a full implementation
from the development tree to follow.

The gic driver has been copied as the interrupt framework is different. It
is expected the two drivers will be merged by the arm intrng project,
however this will need to be imported into the tree and support for arm64
would need to be added.

This includes code developed by myself, SemiHalf, Ed Maste, and Robin
Randhawa from ARM. This has been funded by the FreeBSD Foundation, with
early development by myself in my spare time with assistance from Robin.

Differential Revision: https://reviews.freebsd.org/D2199
Reviewed by: emaste, imp
Relnotes: yes
Sponsored by: The FreeBSD Foundation