WiFi TODO
I am trying to collect a list of things I came across that should be sorted for WiFi in FreeBSD. Some of that is long-overdue cleanup and fixes rather than adding shiny new features. I will try to keep them in to categories.
Long-overdue cleanup and fixes
- net80211 ic locking: various drivers have to unlock in various places in order to talk to hardware as we cannot sleep; deferring everything and using callbacks usually adds more trouble
- net80211 state machine: XXX find commits, when the state machine moved to a taskq to serialize operations we were still left with BSS nodes being swapped under us without properly tearing state down; this troubles firmware based drives (basically all modern ones)
nt (NODE) lock & crypto: same problem as with the ic lock; also inconsistently acquired so we end up in (*iv_key_set/del)() calls with inconsistent locking troubling drivers [see XXX commit and freebsd-wireless on 2025-03-06 for discussion)
- A lot more locking assertions to document assumptions and find unlocked paths updating fields
- regdomain.xml overhaul/review
- reduce the channel list from a gazillion of combinations to a plain list with flags. This needs to adjustments to all of net80211, regdomain, and most drivers.
- personal preference: cleanup a lot of ic/vap/node/.. inconsistencies in structs and flags about hw support, hw state, current announced, received, and in-use options and flags, etc.
- Cleanup dead code (a lot of things are prepared but not used/implemented); either start doing something with or ditch for clarity ("I think I need ..." does not help)
- Fix HW assisted scanning and allow the scan engine to be swapped between scans; the previous attempt is not sufficient to implement this (I tried)
- Fix roaming
- Fix that wpa_supplicant no longer complains about unknown/unsupported IEs
- XXX-BZ find all the annotations in net80211 code and list them here.
Shiny new stuff
- Missing crypto algo (Adrian is working on that)
- Finish LinuxKPI USB and SDIO driver support
- Bring the remaining (mt76, ath1xk, ...) LinuxKPI based wireless drivers over the finish line
- extend channels for 6Ghz and 60Ghz. See also previous section.
- modern drivers tend to want to pull packets from queues when they need them; LinuxKPI has basic an implementation for that; migrate into net80211 for mbufs
WiFi6[E] 11ax
WiFi7 11be prepare for multi-link operation (MLO)
Nice to have
- more automated testing
- more (structured) feedback information to user space
- better statistics reporting
- better radiotap reporting
- a lot more documentation about the various internal parts
- documentation on how to debug wireless (start with the toolbox)
- LinuxKPI wireless drivers with mbuf backed skbs
- LinuxKPI AP mode
- LinuxKPI monitor mode
- Decode the IEs we don't know (see first section as well)