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)

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

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

Check pointer for NULL before dereferencing it, not after.

PR: 138387, 138388
Submitted by: Patroklos Argyroudis <argp@census-labs.com>
MFC after: 1 week

Add locking to ppc and ppbus and mark the whole lot MPSAFE:
- To avoid having a bunch of locks that end up always getting acquired as
a group, give each ppc(4) device a mutex which it shares with all the
child devices including ppbus(4), lpt(4), plip(4), etc. This mutex
is then used for all the locking.
- Rework the interrupt handling stuff yet again. Now ppbus drivers setup
their interrupt handler during attach and tear it down during detach
like most other drivers. ppbus(4) only invokes the interrupt handler
of the device that currently owns the bus (if any) when an interrupt
occurs, however. Also, interrupt handlers in general now accept their
softc pointers as their argument rather than the device_t. Another
feature of the ppbus interrupt handlers is that they are called with
the parent ppc device's lock already held. This minimizes the number
of lock operations during an interrupt.
- Mark plip(4), lpt(4), pcfclock(4), ppi(4), vpo(4) MPSAFE.
- lpbb(4) uses the ppc lock instead of Giant.
- Other plip(4) changes:
- Add a mutex to protect the global tables in plip(4) and free them on
module unload.
- Add a detach routine.
- Split out the init/stop code from the ioctl routine into separate
functions.
- Other lpt(4) changes:
- Use device_printf().
- Use a dedicated callout for the lptout timer.
- Allocate the I/O buffers at attach and detach rather than during
open and close as this simplifies the locking at the cost of
1024+32 bytes when the driver is attached.
- Other ppi(4) changes:
- Use an sx lock to serialize open and close.
- Remove unused HADBUS flag.
- Add a detach routine.
- Use a malloc'd buffer for each read and write to avoid races with
concurrent read/write.
- Other pps(4) changes:
- Use a callout rather than a callout handle with timeout().
- Conform to the new ppbus requirements (regular mutex, non-filter
interrupt handler). pps(4) is probably going to have to become a
standalone driver that doesn't use ppbus(4) to satisfy it's
requirements for low latency as a result.
- Use an sx lock to serialize open and close.
- Other vpo(4) changes:
- Use the parent ppc device's lock to create the CAM sim instead of
Giant.
- Other ppc(4) changes:
- Fix ppc_isa's detach method to detach instead of calling attach.

Tested by: no one :-(

Various whitespace and style fixes.

Several cleanups to remove the need for explicit unit numbers and a few
other fixes:
- Add pointers back to device_t objects in softc structures instead
of storing the unit and using devclass_get_device().
- Add 'lpbb', 'pcf', 'pps', and 'vpo' child devices to every 'ppbus' device
instead of just the first one.
- Store softc pointers in si_drv1 of character devices instead of
pulling the unit number from the minor number and using
devclass_get_softc() and devclass_get_device().
- Store the LP_BYPASS flag in si_drv2 instead of encoding it in the minor
number.
- Destroy character devices for lpt(4) when detaching the device.
- Use bus_print_child_footer() instead of duplicating it in
ppbus_print_child() and fix ppbus_print_child()'s return value.
- Remove unused AVM ivar from ppbus.
- Don't store the 'mode' ivar in the ppbus ivars since we always fetch it
from the parent anyway.
- Try to detach all the child devices before deleting them in
ppbus_detach().
- Use pause() instead of a tsleep() on a dummy address when polling the
ppbus.
- Use if_printf() and device_printf() instead of explicit names with unit
numbers.

Silence on: current@

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

Start each of the license/copyright comments with /*-, minor shuffle of lines

Do not bzero() the softc, as newbus does it for us.

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

Add missing <sys/module.h> includes

Prevent the strange situation that after each load/unload of a ppbus
device, the device is probed multiple times (so each device is
detected N times after unloading/loading the module N-1 times).

The real fix is (quote Doug and Warner):
> : In an ideal world, there should be some kind of BUS_UNIDENTIFY method
> : which a driver could use to delete the devices it created in
> : BUS_IDENTIFY.
>
> Or the bus would have a driver deleted routine that got called and it
> would remove all instances of the devclass attached to it.

Reviewed by: Doug Rabson & Warner Losh

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.

Device megapatch 1/6:

Free approx 86 major numbers with a mostly automatically generated patch.

A number of strategic drivers have been left behind by caution, and a few
because they still (ab)use their major number.

Use __FBSDID().
Also some minor style cleanups.

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)

Synchronize make_dev() for pcfclock devices to the values in MAKEDEV
for consistency.

Submitted by: kris

d_read_t functions return an int, not a ssize_t. (Considering the fact
that read(2) returns a ssize_t perhaps this is a bug in d_read_t?)

This makes ppbus childs like lpt and ppi succesfully connect to more
than just the first ppbus.
The child drivers always tried to attach unit 0.

Reviewed by: gallatin
Approved by: gallatin

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

Style fixes from Sascha

PR: 16551
Submitted by: Sascha Schumann <sascha@schumann.cx>

Send the remains (such as I have located) of "block major numbers" to
the bit-bucket.

Remove unneeded #include <machine/clock.h>

Remove ~25 unneeded #include <sys/conf.h>
Remove ~60 unneeded #include <sys/malloc.h>

Fix buffer overrun in pcfclock_read(). The submitter is the original
author of the affected code.

PR: 16552
Submitted by: Sascha Schumann <sascha@schumann.cx>
Approved by: jkh

Some newbus-inspired tidy-ups. Use device_identify() rather than scanning
the resource table to locate children. The 'at ppbus?' can go again.
Remove a few #if Nxxx > 0' type things, config arranges this for us.
Move the newbus method glue next to the DRIVER_MODULE() stuff so we
don't need extra prototypes.
Don't set device descriptions until after the possibility of the probe
returning an error.
Remove all cdevsw_add() calls, all the drivers that did this also use
make_dev() correctly, so it's not required.
A couple of other minor nits.

Add parallel port clock driver.
Submitted by: Sascha Schumann <sascha@schumann.cx>