linux(4): Staticize lsiginfo_to_siginfo

It's not used outside of linux_signal.c
While here fix the indentation.

MFC after: 1 week

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

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

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

linux(4): Trace Linux l_sigset_t.

MFC after: 2 weeks

linux(4): Move signal codes definitions to the appropriate header

In the Linux the struct siginfo related bits are placed into the siginfo.h
header.

MFC after: 2 weeks

linux(4): Add copyin_sigset() helper.

MFC after: 2 weeks

linux(4): optimize ksiginfo to siginfo conversion.

Retire ksiginfo_to_lsiginfo function, use siginfo_to_lsiginfo instead.
Convert rt_sigtimedwait siginfo variables to well known names.

MFC after: 2 weeks

linux(4): Properly convert linux siginfo to native siginfo
add input validation.

MFC after: 2 weeks

Rationalize license text on Linuxolator files

Many licenses on Linuxolator files contained small variations from the
standard FreeBSD license text. To avoid license proliferation switch to
the standard 2-Clause FreeBSD license for those files where I have
permission from each of the listed copyright holders.

Approved by: rdivacky, marcel
MFC after: 1 week
Sponsored by: The FreeBSD Foundation

sys/compat: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

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.

Rework signal code to allow using it by other modules, like linprocfs:

1. Linux sigset always 64 bit on all platforms. In order to move Linux
sigset code to the linux_common module define it as 64 bit int. Move
Linux sigset manipulation routines to the MI path.

2. Move Linux signal number definitions to the MI path. In general, they
are the same on all platforms except for a few signals.

3. Map Linux RT signals to the FreeBSD RT signals and hide signal conversion
tables to avoid conversion errors.

4. Emulate Linux SIGPWR signal via FreeBSD SIGRTMIN signal which is outside
of allowed on Linux signal numbers.

PR: 197216

According to Linux man sigaltstack(3) shall return EINVAL if the ss
argument is not a null pointer, and the ss_flags member pointed to by ss
contains flags other than SS_DISABLE. However, in fact, Linux also
allows SS_ONSTACK flag which is simply ignored.

For buggy apps (at least mono) ignore other than SS_DISABLE
flags as a Linux do.

While here move MI part of sigaltstack code to the appropriate place.

Reported by: abi at abinet dot ru

Implement rt_sigqueueinfo() system call.

Differential Revision: https://reviews.freebsd.org/D1047
Reviewed by: trasz

Add a siginfo_t conversion function.

Differential Revision: https://reviews.freebsd.org/D1044
Reviewed by: emaste, trasz

Reduce duplication between i386/linux/linux.h and amd64/linux32/linux.h
by moving bits that are MI out into headers in compat/linux.

Reviewed by: Chagin Dmitry dmitry | gmail
MFC after: 2 weeks

Put the macro declaration in the relevant include file for future use.

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

Correctly fill siginfo for the signals delivered by linux tkill/tgkill.
It is required for async cancellation to work.

Fix PROC_LOCK leak in linux_tgkill when signal delivery attempt is made
to not linux process.

Do not call em_find(p, ...) with p unlocked.

Move common code for linux_tkill() and linux_tgkill() into
linux_do_tkill().

Change linux siginfo_t definition to match actual linux one. Extend
uid fields to 4 bytes from 2. The extension does not change structure
layout and is binary compatible with previous definition, because i386
is little endian, and each uid field has 2 byte padding after it.

Reported by: Nicolas Joly <njoly pasteur fr>
Submitted by: dchangin
MFC after: 1 month

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

MFP4 (107868 - 107870):
Use a macro to test for a valid signal instead of doing it my hand everywhere.

Submitted by: rdivacky

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

Round of cleanups and enhancements. These include (in random order):

o Introduce private types for use in linux syscalls for two reasons:
1. establish type independence for ease in porting and,
2. provide a visual queue as to which syscalls have proper
prototypes to further cleanup the i386/alpha split.
Linuxulator types are prefixed by 'l_'. void and char have not
been "virtualized".

o Provide dummy functions for all syscalls and remove dummy functions
or implementations of truely obsolete syscalls.

o Sanitize the shm*, sem* and msg* syscalls.

o Make a first attempt to implement the linux_sysctl syscall. At this
time it only returns one MIB (KERN_VERSION), but most importantly,
it tells us when we need to add additional sysctls :-)

o Bump the kenel version up to 2.4.2 (this is not the same as the
KERN_VERSION MIB, BTW).

o Implement new syscalls, of which most are specific to i386. Our
syscall table is now up to date with Linux 2.4.2. Some highlights:
- Implement the 32-bit uid_t and gid_t bases syscalls.
- Implement a couple of 64-bit file size/offset bases syscalls.

o Fix or improve numerous syscalls and prototypes.

o Reduce style(9) violations while I'm here. Especially indentation
inconsistencies within the same file are addressed. Re-indenting
did not obfuscate actual changes to the extend that it could not
be combined.

NOTE: I spend some time testing these changes and found that if there
were regressions, they were not caused by these changes AFAICT.
It was observed that installing a RH 7.1 runtime environment
did make matters worse. Hangs and/or reboots have been observed
with and without these changes, so when it failed to make life
better in cases it doesn't look like it made it worse.

The MI/MD split wasn't perfect and the MI files need hacks for the
AlphaLinux compat bits. This will be better cleaned up soon.

Agreed to what ever was necessary by: marcel

Fix typo in license.

Provide prototypes for functions used by MD code.