Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

MFC r317055,r317056 (glebius): Include sys/vmmeter.h as included

r317055: All these files need sys/vmmeter.h, but now they got it implicitly
included via sys/pcpu.h.

r317056: Typo!

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

MFC 307332,312086: Drop support for using mmap() with /dev/kmem.

307332:
Drop support for using mmap() with /dev/kmem.

Using the device pager with /dev/kmem is not stable since KVA mappings
are transient, but the device pager caches the PA associated with a
given offset forever. Interestingly, mips' implementation of
memmap() already refused requests for /dev/kmem.

Note that kvm_read/kvm_write do not use mmap, but use read and write on
/dev/kmem, so this should not affect libkvm users.

312086:
Trim a few comments on platforms that did not implement mmap of /dev/kmem.

After r307332, no platforms implement mmap for /dev/kmem, so the lack of
it for these platforms is no longer unique.

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

Remove Giant from /dev/mem and /dev/kmem. It is definitely not needed
for i386, and from the code inspection, nothing in the
arm/mips/sparc64 implementations depends on it.

Discussed with: imp, nwhitehorn
Sponsored by: The FreeBSD Foundation
MFC after: 3 weeks

Simplify memrw().

MFC after: 10 days

Replace kernel virtual address space allocation with vmem. This provides
transparent layering and better fragmentation.

- Normalize functions that allocate memory to use kmem_*
- Those that allocate address space are named kva_*
- Those that operate on maps are named kmap_*
- Implement recursive allocation handling for kmem_arena in vmem.

Reviewed by: alc
Tested by: pho
Sponsored by: EMC / Isilon Storage Division

Disconnect sun4v architecture from the three.

Some files keep the SUN4V tags as a code reference, for the future,
if any rewamped sun4v support wants to be added again.

Reviewed by: marius
Tested by: sbruno
Approved by: re

Remove empty dev_mem_md_init() stubs.

For CPUs which ignore TD_CV and support hardware unaliasing don't
bother doing page coloring. This results in a small but measurable
performance improvement in buildworld times.

Replace all calls to minor() with dev2unit().

After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.

This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.

Reviewed by: kib

- Remove redundant inclusion of opt_global.h.
- Use __FBSDID in autoconf.c.

MFC after: 3 days

Delete the unused/not really used sparc64 (as in sun4u) cache.h,
iommureg.h (which already began to bitrot) and iommuvar.h from the
sun4v source and adjust some of the source which is shared between
sparc64 and sun4v as appropriate.

remove 13 (largely) redundant files and switch to the sparc64/sparc64 version

Reviewed by: jb (mentor rwatson)

Remove superfluous inclusion of upa.h.

Correct some uses of the wrong members of the *min()/*max()-familiy, e.g.
min() on unsigned long. None of these are believed to have been fatal though.

Reviewed by: tmm

Break out the MI part of the /dev/[k]mem and /dev/io drivers into
their own directory and module, leaving the MD parts in the MD
area (the MD parts _are_ part of the modules). /dev/mem and /dev/io
are now loadable modules, thus taking us one step further towards
a kernel created entirely out of modules. Of course, there is nothing
preventing the kernel from having these statically compiled.

Do the dreaded s/dev_t/struct cdev */
Bump __FreeBSD_version accordingly.

Add missing <sys/module.h> instances which were shadowed by the nested
include in <sys/kernel.h>

Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson

Device megapatch 4/6:

Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.

Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.

Prefer new location of pci include files (which have only been in the
tree for two or more years now), except in a few places where there's
code to be compatible with older versions of FreeBSD.

Use vm_paddr_t for physical addresses.

Use td->td_ucred instead of td->td_proc->p_ucred.

Clean up /dev/mem now that pmap handles illegal aliases properly. Don't
allow access to device memory through /dev/mem, or try to make modifying
kernel text through /dev/mem safe (it is not).

Gigacommit to improve device-driver source compatibility between
branches:

Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.

This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.

Approved by: re(scottl)

Back out M_* changes, per decision of the TRB.

Approved by: trb

Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.

Teach /dev/kmem about direct mapped addresses.

Note that a better solution for how to make kernacc work for direct mapped
addresses is needed for all platforms that use them.

Add a driver for the mem and kmem devices, based off the i386 version.