sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

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

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

sys: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

Add RLIM_SAVED_MAX and RLIM_SAVED_CUR symbols.

Define them as RLIM_INFINITY. This is allowed by POSIX in case all
resource limits are representable in an object of type rlim_t. Since
we do not allow negative rlim_t, with some strength this definition is
conforming.

We are not conforming fully still because POSIX requires rlim_t to be
unsigned type. Fixing this without breaking ABI to redefine
RLIM_INFINITY is impossible.

PR: 209729
Submitted by: bltsrc@mail.ru
Exp-run done by: antoine
MFC after: 2 weeks

Define the id_t type as required by POSIX.

It seems that all versions of POSIX that I could find require that
<sys/resource.h> defines id_t. Define it together with rlim_t. While
there, move these typedefs closer to the top of the header file, right
after the includes, which we do in most other header files.

Make RLIM_INFINITY usable without including <stdint.h>.

By using __uint64_t instead of uint64_t, this constant can also be used
if <sys/resource.h> is included on its own.

Implement process-shared locks support for libthr.so.3, without
breaking the ABI. Special value is stored in the lock pointer to
indicate shared lock, and offline page in the shared memory is
allocated to store the actual lock.

Reviewed by: vangyzen (previous version)
Discussed with: deischen, emaste, jhb, rwatson,
Martin Simmons <martin@lispworks.com>
Tested by: pho
Sponsored by: The FreeBSD Foundation

Add a resource limit for the total number of kqueues available to the
user. Kqueue now saves the ucred of the allocating thread, to
correctly decrement the counter on close.

Under some specific and not real-world use scenario for kqueue, it is
possible for the kqueues to consume memory proportional to the square
of the number of the filedescriptors available to the process. Limit
allows administrator to prevent the abuse.

This is kernel-mode side of the change, with the user-mode enabling
commit following.

Reported and tested by: pho
Discussed with: jmg
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks

Add the wait6(2) system call. It takes POSIX waitid()-like process
designator to select a process which is waited for. The system call
optionally returns siginfo_t which would be otherwise provided to
SIGCHLD handler, as well as extended structure accounting for child
and cumulative grandchild resource usage.

Allow to get the current rusage information for non-exited processes
as well, similar to Solaris.

The explicit WEXITED flag is required to wait for exited processes,
allowing for more fine-grained control of the events the waiter is
interested in.

Fix the handling of siginfo for WNOWAIT option for all wait*(2)
family, by not removing the queued signal state.

PR: standards/170346
Submitted by: "Jukka A. Ukkonen" <jau@iki.fi>
MFC after: 1 month

Add const qualifier to rlimit_ident.

Reviewed by: kib
MFC after: 2 weeks

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Style fix - keep the line length below 80 characters.

Submitted by: bde@

Style fix.

MFC r207468:
Extract thread_lock()/ruxagg()/thread_unlock() fragment into utility
function ruxagg_tlock().
Convert the definition of kern_getrusage() to ANSI C.

MFC r207602:
Implement RUSAGE_THREAD. Add td_rux to keep extended runtime and ticks
information for thread to allow calcru1() (re)use.

Rename ruxagg()->ruxagg_locked(), ruxagg_tlock()->ruxagg() [1].
The ruxagg_locked() function no longer clears thread ticks nor
td_incruntime.

Not an MFC: the td_rux is added to the end of struct thread to keep
the KBI. Explicit bzero() of td_rux is added to new thread initialization
points.

Implement RUSAGE_THREAD. Add td_rux to keep extended runtime and ticks
information for thread to allow calcru1() (re)use.

Rename ruxagg()->ruxagg_locked(), ruxagg_tlock()->ruxagg() [1].
The ruxagg_locked() function no longer clears thread ticks nor
td_incruntime.

Requested by: attilio [1]
Discussed with: attilio, bde
Reviewed by: bde
Based on submission by: Alexander Krizhanovsky <ak natsys-lab com>
MFC after: 1 week
X-MFC-Note: td_rux shall be moved to the end of struct thread

Implement global and per-uid accounting of the anonymous memory. Add
rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved
for the uid.

The accounting information (charge) is associated with either map entry,
or vm object backing the entry, assuming the object is the first one
in the shadow chain and entry does not require COW. Charge is moved
from entry to object on allocation of the object, e.g. during the mmap,
assuming the object is allocated, or on the first page fault on the
entry. It moves back to the entry on forks due to COW setup.

The per-entry granularity of accounting makes the charge process fair
for processes that change uid during lifetime, and decrements charge
for proper uid when region is unmapped.

The interface of vm_pager_allocate(9) is extended by adding struct ucred *,
that is used to charge appropriate uid when allocation if performed by
kernel, e.g. md(4).

Several syscalls, among them is fork(2), may now return ENOMEM when
global or per-uid limits are enforced.

In collaboration with: pho
Reviewed by: alc
Approved by: re (kensmith)

Don't forget to add "npts" to rlimit_ident[] as well.

When I added RLIMIT_NPTS, I forgot to add it to rlimit_ident[]. Make
sure the rlimit_ident[] array is always RLIM_NLIMITS elements big. So if
we ever forget to add new rlimits to this list again. it will contain a
null pointer, instead of random data.

Spotted by: rwatson

- Import the HEAD csup code which is the basis for the cvsmode work.

Integrate the new MPSAFE TTY layer to the FreeBSD operating system.

The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.

If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).

The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan

Move the shared cp_time array (counts %sys, %user, %idle etc) to the
per-cpu area. cp_time[] goes away and a new function creates a merged
cp_time-like array for things like linprocfs, sysctl etc. The
atomic ops for updating cp_time[] in statclock go away, and the scope
of the thread lock is reduced.

sysctl kern.cp_time returns a backwards compatible cp_time[] array.
A new kern.cp_times sysctl returns the individual per-cpu stats.

I have pending changes to make top and vmstat optionally show per-cpu
stats.

I'm very aware that there are something like 5 or 6 other versions "out
there" for doing this - but none were handy when I needed them.

I did merge my changes with John Baldwin's, and ended up replacing a
few chunks of my stuff with his, and stealing some other code.

Reviewed by: jhb
Partly obtained from: jhb

- Move rusage from being per-process in struct pstats to per-thread in
td_ru. This removes the requirement for per-process synchronization in
statclock() and mi_switch(). This was previously supported by
sched_lock which is going away. All modifications to rusage are now
done in the context of the owning thread. reads proceed without locks.
- Aggregate exiting threads rusage in thread_exit() such that the exiting
thread's rusage is not lost.
- Provide a new routine, rufetch() to fetch an aggregate of all rusage
structures from all threads in a process. This routine must be used
in any place requiring a rusage from a process prior to it's exit. The
exited process's rusage is still available via p_ru.
- Aggregate tick statistics only on demand via rufetch() or when a thread
exits. Tick statistics are kept in the thread and protected by sched_lock
until it exits.

Initial patch by: attilio
Reviewed by: attilio, bde (some objections), arch (mostly silent)

Correct description of RLIMIT_CPU.

Reported by: bde

/* -> /*- for license, minor formatting changes

- Move the function prototypes for kern_setrlimit() and kern_wait() to
sys/syscallsubr.h where all the other kern_foo() prototypes live.
- Resort kern_execve() while I'm there.

Fix signedness idiocy in previous commit. Pass the pointy hat...

Back out previous commit; INT64_MAX (defined in <stdint.h>) is not always
visible when <sys/resource.h> is included.

Document why rlim_t needs to be a signed type.
Define RLIM_INFINITY as INT64_MAX instead of hand-rolling it.

MFC after: 1 week

Add locking notes on the members of rusage. Note that these notes reflect
what is already present in the tree and apply to the rusage struct for
current process usage rather than child process usage.

Make this header a little bit more XSI-compliant:
- Define type rlim_t and struct timeval. This makes autoconf
happier. (PR: 62388)
- Add RLIMIT_AS, which is an alias for our RLIMIT_VMEM.
- structs orlimit and loadavg, as well as macros CP*, should
only appear if __BSD_VISIBLE.
- Use underscored versions of int32_t and fixpt_t in case
<sys/types.h> is not included.
- Document areas of non-conformance.

Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core

Locking for the per-process resource limits structure.
- struct plimit includes a mutex to protect a reference count. The plimit
structure is treated similarly to struct ucred in that is is always copy
on write, so having a reference to a structure is sufficient to read from
it without needing a further lock.
- The proc lock protects the p_limit pointer and must be held while reading
limits from a process to keep the limit structure from changing out from
under you while reading from it.
- Various global limits that are ints are not protected by a lock since
int writes are atomic on all the archs we support and thus a lock
wouldn't buy us anything.
- All accesses to individual resource limits from a process are abstracted
behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return
either an rlimit, or the current or max individual limit of the specified
resource from a process.
- dosetrlimit() was renamed to kern_setrlimit() to match existing style of
other similar syscall helper functions.
- The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit()
(it didn't used the stackgap when it should have) but uses lim_rlimit()
and kern_setrlimit() instead.
- The svr4 compat no longer uses the stackgap for resource limits calls,
but uses lim_rlimit() and kern_setrlimit() instead.
- The ibcs2 compat no longer uses the stackgap for resource limits. It
also no longer uses the stackgap for accessing sysctl's for the
ibcs2_sysconf() syscall but uses kernel_sysctl() instead. As a result,
ibcs2_sysconf() no longer needs Giant.
- The p_rlimit macro no longer exists.

Submitted by: mtm (mostly, I only did a few cleanups and catchups)
Tested on: i386
Compiled on: alpha, amd64

- Remove PRIO_TOTAL.

Submitted by: bde

Move cp_time[CPUSTATES] and related #defines to <sys/resource.h>

Part I of RLIMIT_VMEM implementation. Implement core functionality for
a new resource limit that covers a process's entire VM space, including
mmap()'d space.

(Part II will be additional code to check RLIMIT_VMEM during exec() but it
needs more fleshing out).

PR: kern/18209
Submitted by: Andrey Alekseyev <uitm@zenon.net>, Dmitry Kim <jason@nichego.net>
MFC after: 7 days

Remove __P

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(9) the structure definitions.

add prototype for dosetrlimit

Change the scheduler to actually respect the PUSER barrier. It's been
wrong for many years that negative niceness would lower the priority
of a process below PUSER, and once below PUSER, there were conditionals
in the code that are required to test for whether a process was in
the kernel which would break.

The breakage could (and did) cause lock-ups, basically nothing else
but the least nice program being able to run in some conditions. The
algorithm which adjusts the priority now subtracts PRIO_MIN to do
things properly, and the ESTCPULIM() algorithm was updated to use
PRIO_TOTAL (PRIO_MAX - PRIO_MIN) to calculate the estcpu.

NICE_WEIGHT is now 1 to accomodate the full range of priorities better
(a -20 process with full CPU time has the priority of a +0 process with
no CPU time). There are now 20 queues (exactly; 80 priorities) for
use in user processes' scheduling, and PUSER has been lowered to 48
to accomplish this.

This means, to the user, that things will be scheduled more correctly
(noticeable), there is no lock-up anymore WRT a niced -20 process
never releasing the CPU time for other processes. In this fair system,
tsleep()ed < PUSER processes now will get the proper higher priority
than priority >= PUSER user processes.

The detective work of this was done by me, along with part of the
solution. Luoqi Chen has provided most of the solution, and really
helped me understand what was happening better, to boot :)

Submitted by: luoqi
Concept reviewed by: bde

Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.

Implement RLIMIT_SBSIZE in the kernel. This is a per-uid sockbuf total
usage limit.

$Id$ -> $FreeBSD$

Add a new "file" to procfs: "rlimit" which shows the resource limits for
the process.

PR: 11342
Submitted by: Adrian Chadd adrian@freebsd.org
Reviewed by: phk

Don't #include <sys/types.h>. I mistakenly #included it unconditionally
to fix some broken application. Application breakage is now hidden by a
recently introduced wrong #include of <sys/types.h> in <sys/time.h>.
<sys/time.h> is a prerequisite for <sys/resource.h>, so the <sys/types.h>
prereqisite is automatically supplied.

Cast RLIM_INFINITY to the correct (signed) type.

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Use rlim_t for rlim_cur, rlim_max as supposed

Import 4.4BSD-Lite2 onto the vendor branch, note that in the kernel, all
files are off the vendor branch, so this should not change anything.

A "U" marker generally means that the file was not changed in between
the 4.4Lite and Lite-2 releases, and does not need a merge. "C" generally
means that there was a change.
[new sys/syscallargs.h file, to be "cvs rm"ed]

Merge in Lite2: use fixed-width types.
Reviewed by: davidg & bde

#Include <sys/types.h> so that <sys/resource.h> can be #included without
explicitly #including <sys/types.h>. Some gnu software (?gdb) depends on
this and broke when I fixed <stdio.h> to not include <sys/types.h>.

Bruce

Added $Id$

BSD 4.4 Lite Kernel Sources