We should set the STA deflink addresses in case no
link is really added.

Fixes: 046d2e7c ("mac80211: prepare sta handling for MLO support")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Maintain a hash table of link-sta addresses so we can find
them for management frames etc. where addresses haven't
been replaced by the drivers to the MLD address yet.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We need to be able to access these in a race-free way under
traffic while adding/removing them, so RCU-ify the pointers.
This requires passing a link_sta to a lot of functions so
we don't have to do the RCU handling everywhere.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Hardcoding link[0] is more confusing than using deflink,
so use deflink for now, which requires making the macro
a bit safer.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This is only used in rx.c, so move it into the file.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Pass the link id through to the get_beacon and return
the beacon for a specific link id.
Signed-off-by: Shaul Triebitz <shaul.triebitz@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In start_ap and stop_ap mac80211 callbacks pass the link_id
to the drivers.
Signed-off-by: Shaul Triebitz <shaul.triebitz@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Use link and link_conf according to the link_id
provided by cfg in start_ap/stop_ap and change_beacon.
Also use them in the functions called by them.
Note that for a non MLD device, the link_id is 0,
and link[0] and link_conf[0] equal to deflink and
bss_conf respectively (what was there before).

Also, call vif_info_change for BSS related changes (SSID), and
link_info_change for LINK related changes (instead of the
legacy bss_info_change).
Signed-off-by: Shaul Triebitz <shaul.triebitz@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When a link is added or removed via nl80211, these are
called. Implement them so we don't have to check in all
the different per-link commands whether we've already
created the necessary datastructures.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add some optional callbacks for link add/remove so that
drivers can react here. Initially, I thought it would be
sufficient to just create the link in start_ap etc., but
it turns out that's not so simple, since there are quite
a few callbacks that can be called: if they're erroneously
without start_ap, things might crash.

Thus it might be easier for drivers to allocate all the
necessary data structures immediately, to not have to
worry about it in each callback, since cfg80211 checks
that the link ID is valid (has been added.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We wanted to have this sorted by direction (to/from driver),
but didn't maintain that well. Sort the file now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add the necessary infrastructure, including a new driver
method, to add/remove links to/from a station. To do this,
refactor the link alloc/free a bit, splitting that so we
can do it without linking them, to handle failures better.

Note that a station entry must be created representing an
MLD or a non-MLD STA, it cannot change between the two.
When representing an MLD, the 'deflink' is used for the
first link, which might be removed later, in which case
the memory isn't reused.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Take a few bits out of the control.flags to add the link ID
to TX frame metadata, so drivers don't need to look it up
by the address themselves. Implement that lookup where it's
needed, for internal frame TX, and set it to "unspecified"
for data transmissions.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If the interface is an MLD, then we don't know which band
the frame will be transmitted on, and we don't know how to
look up the band. Set the band information to zero in that
case, the driver cannot rely on it anyway.

No longer inline ieee80211_tx_skb_tid() since it's even
bigger now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add the necessary infrastructure, including a new driver
method, to add/remove links to/from an interface.

Also add the missing link address to bss_conf (which we
use as link_conf too), and fill it, in station mode for
now just randomly, in AP mode we get the address from
cfg80211 since the link must be created with an address
first.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For authentication, we need the BSS, the link_id and the AP
MLD address to create the link and station, (for now) the
driver assigns a link address and sends the frame, the MLD
address needs to be the address of the interface.

For association, pass the list of BSSes that were selected
for the MLO connection, along with extra per-STA profile
elements, the AP MLD address and the link ID on which the
association request should be sent.

Note that for now we don't have a proper way to pass the link
address(es) and so the driver/mac80211 will select one, but
depending on how that selection works it means that assoc w/o
auth data still being around (mac80211 implementation detail)
the association won't necessarily work - so this will need to
be extended in the future to sort out the link addressing.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When channel contexts are used, IEEE80211_CONF_CHANGE_SMPS
doesn't make sense and doesn't apply (which is documented).
Mask it in this case.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Replace the bss_info_changed callback with vif_cfg_changed
and link_info_changed callbacks (for vif changes and link
changes).
Signed-off-by: Shaul Triebitz <shaul.triebitz@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This function has far too many parameters now, move out
the BSS lookup and pass the request struct instead.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add the definitions necessary to build and parse some of the
multi-link element, the per-STA profile isn't fully included.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For MLO we'll need to do this multiple times, so refactor
this. For now keep the disconnect_bssid, but we'll need to
figure out how to handle that with MLD.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Today it makes more sense to pass the necessary parameters to
look up the BSS entry to cfg80211_mlme_assoc(), but with MLO
we will need to look up multiple, and that gets awkward. Pull
the lookup code into the callers so we can change it better.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In ieee80211_build_hdr() we do the same thing for all
interface types except for AP_VLAN, but we can simplify
the code by pulling the common thing in front of the
switch and overriding it for AP_VLAN. This will also
simplify the code for MLD here later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For MLD, we might eventually not really know the band on status,
but some code assumes it's there. Move the sband lookup deep to
the code that actually needs it, to make it clear where exactly
it's needed and for what purposes.

For rate control, at least initially we won't support it in MLO,
so that won't be an issue.

For TX monitoring, we may have to elide the rate and/or rely on
ieee80211_tx_status_ext() for rate information.

This also simplifies the function prototypes.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This used to be sorted by driver methods, APIs and internal
functions, but got added to in the wrong sections. Fix that
by ordering the file properly again.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We need to no longer use bss_conf here, but the per-link data.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add the link_id parameter and adjust the code accordingly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Start making some SMPS related code MLD-aware. This isn't
really done yet, but again cuts down our 'deflink' reliance.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Update ieee80211_ht_cap_ie_to_sta_ht_cap() to handle per-link
data.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Update the code in eht.c and add the link_id parameter where
necessary.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Update the code in vht.c and add the link_id parameter where
necessary.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We don't need to setup lists and work structs every time
we switch the interface type, factor that out into a new
ieee80211_link_init() function and use it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If MLO is enabled by the driver then validate a set of
capabilities that mac80211 will initially not support
in MLO. This might change if features are implemented.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Remove MAX_STA_LINKS and use IEEE80211_MLD_MAX_NUM_LINKS
instead to unify between the station and other data structures.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Refactor the code a bit to initialize a link belonging
to a station, and (later) free all allocated links.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The function is unused since commit 52b4810b ("mac80211: Remove
support for changing AP SMPS mode") so we can just remove it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Make the channel context code MLO aware, along with some
functions that it uses, so that the chan.c file is now
MLD-clean and no longer uses deflink/bss_conf/etc.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In a few cases we already have the link ID in the APIs,
pass it already even if it cannot be non-zero yet.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add pointers so we can start using link_id throughout the
code, even if for now only link ID 0 is valid, pointing
to the "built-in" bss_conf, which is used by drivers that
are not aware of MLD.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Split the bss_info_changed method to vif_cfg_changed and
link_info_changed, with the latter getting a link ID.
Also change the 'changed' parameter to u64 already, we
know we need that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>