cfg80211: change netdev registration/unregistration semantics

We used to not require anything in terms of registering netdevs
with cfg80211, using a netdev notifier instead. However, in the
next patch reducing RTNL locking, this causes big problems, and
the simplest way is to just require drivers to do things better.

Change the registration/unregistration semantics to require the
drivers to call cfg80211_(un)register_netdevice() when this is
happening due to a cfg80211 request, i.e. add_virtual_intf() or
del_virtual_intf() (or if it somehow has to happen in any other
cfg80211 callback).

Otherwise, in other contexts, drivers may continue to use the
normal netdev (un)registration functions as usual.

Internally, we still use the netdev notifier and track (by the
new wdev->registered bool) if the wdev had already been added
to cfg80211 or not.

Link: https://lore.kernel.org/r/20210122161942.cf2f4b65e4e9.Ida8234e50da13eb675b557bac52a713ad4eddf71@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index 3dd28f5fef19..6cf308d5934c 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -657,7 +657,7 @@ int brcmf_net_attach(struct brcmf_if *ifp, bool rtnl_locked)
 	INIT_WORK(&ifp->ndoffload_work, _brcmf_update_ndtable);
 
 	if (rtnl_locked)
-		err = register_netdevice(ndev);
+		err = cfg80211_register_netdevice(ndev);
 	else
 		err = register_netdev(ndev);
 	if (err != 0) {
@@ -681,7 +681,7 @@ void brcmf_net_detach(struct net_device *ndev, bool rtnl_locked)
 {
 	if (ndev->reg_state == NETREG_REGISTERED) {
 		if (rtnl_locked)
-			unregister_netdevice(ndev);
+			cfg80211_unregister_netdevice(ndev);
 		else
 			unregister_netdev(ndev);
 	} else {
@@ -758,7 +758,7 @@ int brcmf_net_mon_attach(struct brcmf_if *ifp)
 	ndev = ifp->ndev;
 	ndev->netdev_ops = &brcmf_netdev_ops_mon;
 
-	err = register_netdevice(ndev);
+	err = cfg80211_register_netdevice(ndev);
 	if (err)
 		bphy_err(drvr, "Failed to register %s device\n", ndev->name);