Remove almost unused `flags' argument of suser().

The account flag `ASU' will no longer be set but that makes suser()
mpsafe since it no longer mess with a per-process field.

No objection from millert@, ok tedu@, bluhm@

amd64_{get,set}_fsbase() are superfluous and unused; delete them.
Delete unused/never-implemented sysarch defines and structs while here.

ports check and ok naddy@
ok deraadt@ mlarkin@

reduce the amount of includes in arch/amd64
ok mpi@ deraadt@

amd64 needs FS.base values (the TCB pointer) to be validated, as noncanonical
addresses will cause a fault on load by the kernel.

Problem observed by Maxime Villard
ok kettenis@ deraadt@

branches: 1.16.6; 1.16.10;
Do lazy update/reset of the FS.base and %[def]s segment registers: reseting
segment registers in cpu_switchto if the old thread had made it to userspace
and restoring FS.base only on first return to userspace since context switch.

ok mlarkin@

Remove some includes include-what-you-use claims don't
have any direct symbols used. Tested for indirect use by compiling
amd64/i386/sparc64 kernels.

ok tedu@ deraadt@

Don't need gdt.h here

remove never used get/set ioperm sysarch functions. ok guenther

Unrevert the FS.base diff: the issues were actually elsewhere
Additional testing by jasper@ and pea@

Revert bulk of the FS.base diff, as it causes issues on some machines
and the problem isn't obvious yet.

Add support for per-rthread base-offset for the %fs selector on amd64.
Add pcb_fsbase to the PCB for tracking what the value for the thread
is, and ci_cur_fsbase to struct cpu_info for tracking the CPU's current
value for FS.base, then on return to user-space, skip the setting if the
CPU has the right value already. Non-threaded processes without TLS leave
FS.base zero, which can be conveniently optimized: setting %fs zeros
FS.base for fewer cycles than wrmsr.

ok kettenis@

Old-style MTRRs were never used on amd64, so remove the remaining traces
of them, as well as some other unused proc md_flags bits: MDP_COMPAT and
MDP_SYSCALL.

ok mikeb@

First pass at removing clauses 3 and 4 from NetBSD licenses.

Not sure what's more surprising: how long it took for NetBSD to
catch up to the rest of the BSDs (including UCB), or the amount of
code that NetBSD has claimed for itself without attributing to the
actual authors.

OK deraadt@

Synchronize the MTRR API with i386, and enable

"just commit it" deraadt@

- remove USER_LDT, it was never in a state where it would copile, nor will
we support i386-compat mode on amd64.

agreed by beck@, dlg@, kettenis@
ok deraadt@, tom@

ansi/deregister

Make routines which may set PSL_IOPL consistent wrt the securelevel for
which this is allowed; ok deraadt@

move to amd64_() functions

aperture stuff

branches: 1.1.2;
an amd64 arch support.
hacked by art@ from netbsd sources and then later debugged
by me into the shape where it can host itself.
no bootloader yet as needs redoing from the
recent advanced i386 sources (anyone? ;)

amd64_{get,set}_fsbase() are superfluous and unused; delete them.
Delete unused/never-implemented sysarch defines and structs while here.

ports check and ok naddy@
ok deraadt@ mlarkin@

reduce the amount of includes in arch/amd64
ok mpi@ deraadt@

amd64 needs FS.base values (the TCB pointer) to be validated, as noncanonical
addresses will cause a fault on load by the kernel.

Problem observed by Maxime Villard
ok kettenis@ deraadt@

branches: 1.16.6; 1.16.10;
Do lazy update/reset of the FS.base and %[def]s segment registers: reseting
segment registers in cpu_switchto if the old thread had made it to userspace
and restoring FS.base only on first return to userspace since context switch.

ok mlarkin@

Remove some includes include-what-you-use claims don't
have any direct symbols used. Tested for indirect use by compiling
amd64/i386/sparc64 kernels.

ok tedu@ deraadt@

Don't need gdt.h here

remove never used get/set ioperm sysarch functions. ok guenther

Unrevert the FS.base diff: the issues were actually elsewhere
Additional testing by jasper@ and pea@

Revert bulk of the FS.base diff, as it causes issues on some machines
and the problem isn't obvious yet.

Add support for per-rthread base-offset for the %fs selector on amd64.
Add pcb_fsbase to the PCB for tracking what the value for the thread
is, and ci_cur_fsbase to struct cpu_info for tracking the CPU's current
value for FS.base, then on return to user-space, skip the setting if the
CPU has the right value already. Non-threaded processes without TLS leave
FS.base zero, which can be conveniently optimized: setting %fs zeros
FS.base for fewer cycles than wrmsr.

ok kettenis@

Old-style MTRRs were never used on amd64, so remove the remaining traces
of them, as well as some other unused proc md_flags bits: MDP_COMPAT and
MDP_SYSCALL.

ok mikeb@

First pass at removing clauses 3 and 4 from NetBSD licenses.

Not sure what's more surprising: how long it took for NetBSD to
catch up to the rest of the BSDs (including UCB), or the amount of
code that NetBSD has claimed for itself without attributing to the
actual authors.

OK deraadt@

Synchronize the MTRR API with i386, and enable

"just commit it" deraadt@

- remove USER_LDT, it was never in a state where it would copile, nor will
we support i386-compat mode on amd64.

agreed by beck@, dlg@, kettenis@
ok deraadt@, tom@

ansi/deregister

Make routines which may set PSL_IOPL consistent wrt the securelevel for
which this is allowed; ok deraadt@

move to amd64_() functions

aperture stuff

branches: 1.1.2;
an amd64 arch support.
hacked by art@ from netbsd sources and then later debugged
by me into the shape where it can host itself.
no bootloader yet as needs redoing from the
recent advanced i386 sources (anyone? ;)