Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Toss bogus mergeinfo.

MFC r235634

Fix and update battery status bits according to linux driver

MFC: 229965

Fix for PR 138526.

Add the ability for /dev/null and /dev/zero to accept
being set into non blocking mode via fcntl(). This
brings the code into compliance with IEEE Std 1003.1-2001
as referenced in another PR, 94729.

Reviewed by: jhb

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Move the ZERO_REGION_SIZE to a machine-dependent file, as on many
architectures (i386, for example) the virtual memory space may be
constrained enough that 2MB is a large chunk. Use 64K for arches
other than amd64 and ia64, with special handling for sparc64 due to
differing hardware.

Also commit the comment changes to kmem_init_zero_region() that I
missed due to not saving the file. (Darn the unfamiliar development
environment).

Arch maintainers, please feel free to adjust ZERO_REGION_SIZE as you
see fit.

Requested by: alc
MFC after: 1 week
MFC with: r221853

Usa a globally visible region of zeros for both /dev/zero and the md
device. There are likely other kernel uses of "blob of zeros" than can
be converted.

Reviewed by: alc
MFC after: 1 week

Mark /dev/zero and /dev/null as eternal.

In collaboration with: pho
MFC after: 1 month

Remove unneeded minor numbers from /dev/null and /dev/zero.

Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges. These may
require some future tweaking.

Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>

Use dynamic major number allocation.

Go back to the historical minor numbers. Add a module version while
I'm here.

Asked for minor numbers by: jhb

YA oops. Remove code that was being tested locally.

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 a pass over all modules in the kernel and make them return EOPNOTSUPP
for unknown events.

A number of modules return EINVAL in this instance, and I have left
those alone for now and instead taught MOD_QUIESCE to accept this
as "didn't do anything".

Micro-tweaking.

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

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.

Shorten the code by removing one "do-nothing" function, replacing it
with nullop(), which is in kern_conf.c.

Mark as __unused some arguments that are, erm, unused.

Return ENOIOCTL for unknown ioctls, don't use noioctl to return ENODEV.

The present defaults for the open and close for device drivers which
provide no methods does not make any sense, and is not used by any
driver.

It is a pretty hard to come up with even a theoretical concept of
a device driver which would always fail open and close with ENODEV.

Change the defaults to be nullopen() and nullclose() which simply
does nothing.

Remove explicit initializations to these from the drivers which
already used them.

Use __FBSDID().
Also some minor style cleanups.

/dev/null and /dev/zero does not need Giant

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)

Don't use evil casts in cdevsw initialization.

Warns and lint fix. Nearly all trivial stuff.

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.

Everywhere else, an argument passed to a device containing flags
is called "flags". Make it so here.

Modernise the cdevsw WRT to (unused) kqueue.

Rename DIOCGKERNELDUMP to DIOCSKERNELDUMP as it strictly speaking
is a "set" not a "get" operation.

Sponsored by: DARPA & NAI Labs.

Move generic disk ioctls from <sys/disklabel.h> to <sys/disk.h>.

Sponsored by: DARPA & NAI Labs

Change the suser() API to take advantage of td_ucred as well as do a
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.

Discussed on: smp@

Here follows the new kernel dumping infrastructure.

Caveats:

The new savecore program is not complete in the sense that it emulates
enough of the old savecores features to do the job, but implements none
of the options yet.

I would appreciate if a userland hacker could help me out getting savecore
to do what we want it to do from a users point of view, compression,
email-notification, space reservation etc etc. (send me email if
you are interested).

Currently, savecore will scan all devices marked as "swap" or "dump" in
/etc/fstab _or_ any devices specified on the command-line.

All architectures but i386 lack an implementation of dumpsys(), but
looking at the i386 version it should be trivial for anybody familiar
with the platform(s) to provide this function.

Documentation is quite sparse at this time, more to come.

Details:

ATA and SCSI drivers should work as the dump formatting code has been
removed. The IDA, TWE and AAC have not yet been converted.

Dumpon now opens the device and uses ioctl(DIOCGKERNELDUMP) to set
the device as dumpdev. To implement the "off" argument, /dev/null
is used as the device.

Savecore will fail if handed any options since they are not (yet)
implemented. All devices marked "dump" or "swap" in /etc/fstab
will be scanned and dumps found will be saved to diskfiles
named from the MD5 hash of the header record. The header record
is dumped in readable format in the .info file. The kernel
is not saved. Only complete dumps will be saved.

All maintainer rights for this code are disclaimed: feel free to
improve and extend.

Sponsored by: DARPA, NAI Labs

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

Convert more malloc+bzero to malloc+M_ZERO.

Submitted by: josh@zipperup.org
Submitted by: Robert Drehmel <robd@gmx.net>

During a verbose boot, call the null device 'null' rather than 'null0' to
be more consistent with the rest of the kernel.

Move sys/dev/nulldev to sys/dev/null to be more consistent with naming
under sys/dev.

Small style change; make function names less likely to clash with
existing names. "null" is too common a string; use "null_".

New machine independant /dev/null and /dev/zero driver. This device is
severely stripped down compared with its predecessor, and is measurably
a _lot_ faster.

Many thanks to Jeroen van Gelderen for lots of good ideas.

There is still a problem with this; it is written as a mudule, and as
such is theoretically unloadable. However, there is no refcounting done
as I would prefer to do that a'la device_busy(9), rather than some
"home-rolled" scheme. The point is pretty moot, as /dev/null is
effectively compulsory.

Reviewed by: dfr