sys: Remove $FreeBSD$: one-line .c comment pattern

Remove /^/[*/]\s*\$FreeBSD\$.*\n/

Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (7 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all low hanging fruits as MPSAFE.

Reviewed by: markj
Approved by: kib (mentor, blanket)
Differential Revision: https://reviews.freebsd.org/D23626

net80211: reuse TICKS_2_MSEC / MSEC_2_TICKS macros from sys/time.h

Replace in-place implementation with system-wide one; since it
guarantees non-zero result drop all less-than-one checks from
drivers and net80211.

MFC after: 2 weeks

net80211: fix possible panic for some drivers after r342211

Check if rate control structures were allocated before trying to
access them in various places; this was possible before on
allocation failure (unlikely), but was revealed after r342211
where allocation was deferred.

In case if driver uses wlan_amrr(4) and it is loaded it
is possible to reproduce the panic via

sysctl net.wlan.<number>.rate_stats

(for wlan0 the number will be 0).

Tested with: RTL8188EE, AP mode + RTL8188CUS, STA mode.

MFC after: 3 days

sys: general 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.

No functional change intended.

net80211: do not allow to unload rate control module if it is still in use.

Keep 'nrefs' counter up-to-date, so 'kldunload wlan_amrr' with 1+ active
wlan(4) interface will not lead to kernel panic.

MFC after: 5 days

net80211: ieee80211_ratectl*: switch to reusable KPI

Replace various void * / int argument combinations with common structures:
- ieee80211_ratectl_tx_status for *_tx_complete();
- ieee80211_ratectl_tx_stats for *_tx_update();

While here, improve amrr_tx_update() for a bit:
1. In case, if receiver is not known (typical for Ralink USB drivers),
refresh Tx rate for all nodes on the interface.
2. There was a misuse:
- otus(4) sends non-decreasing counters (as originally intended);
- but ural(4), rum(4) and run(4) are using 'read & clear' registers
to obtain statistics for some period of time (and those 'last period'
values are used as arguments for tx_update()). If arguments are not big
enough, they are just discarded after the next call.

Fix: move counting into *_tx_update()
(now otus(4) will zero out all node counters after every tx_update() call)

Tested with:
- Intel 3945BG (wpi(4)), STA mode.
- WUSB54GC (rum(4)), STA / HOSTAP mode.
- RTL8188EU (urtwn(4)), STA mode.

Reviewed by: adrian
Differential Revision: https://reviews.freebsd.org/D8037

Convert malloc/free back to #define's, as part of OS portability work.

DragonflyBSD uses the FreeBSD wireless stack and drivers. Their malloc()
API is named differently, so they don't have userland/kernel symbol
clashes like we do (think libuinet.)

So, to make it easier for them and to port to other BSDs/other operating
systems, start hiding the malloc specific bits behind defines in
ieee80211_freebsd.h.

DragonflyBSD can now put these portability defines in their local
ieee80211_dragonflybsd.h.

This should be a great big no-op for everyone running wifi.

TODO:

* kill M_WAITOK - some platforms just don't want you to use it
* .. and/or handle it returning NULL rather than waiting forever.
* MALLOC_DEFINE() ?
* Migrate the well-known malloc names (eg M_TEMP) to net80211
namespace defines.

Include necessary headers that now are available due to pollution
via if_var.h.

Sponsored by: Netflix
Sponsored by: Nginx, Inc.

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

Remove GNU-style struct initialization.

Spotted by: clang
Approved by: rpaulo

MFC r206367, r206358, r206370, r206371, r206372, r206398, r206415,
r206416, r206417, r206418, r206418:

net80211 ratectl framework.

When in the RUN -> AUTH -> RUN FSM transition happens, we'll call the
ratectl_node_init() functions and since ni_rtctls was already
malloc'ed() we will panic. Fix this by using the already malloc'ed
pointer.

Found by: bschmidt
Reviewed by: bschmidt

Use M_NOWAIT instead of M_WAITOK to avoid race conditions.

MFC after: 1 month

net80211 rate control framework (net80211 ratectl).

This framework allows drivers to abstract the rate control algorithm and
just feed the framework with the usable parameters. The rate control
framework will now deal with passing the parameters to the selected
algorithm. Right now we have AMRR (the default) and RSSADAPT but there's
no way to select one with ifconfig, yet.
The objective is to have more rate control algorithms in the net80211
stack so all drivers[0] can use it. Ideally, we'll have the well-known
sample rate control algorithm in the net80211 at some point so all
drivers can use it (not just ath).

[0] all drivers that do rate control in software, that is.

Reviewed by: bschmidt, thompsa, weyongo
MFC after: 1 months

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

Multi-bss (aka vap) support for 802.11 devices.

Note this includes changes to all drivers and moves some device firmware
loading to use firmware(9) and a separate module (e.g. ral). Also there
no longer are separate wlan_scan* modules; this functionality is now
bundled into the wlan module.

Supported by: Hobnob and Marvell
Reviewed by: many
Obtained from: Atheros (some bits)