[RFC 5/8] ath10k: protect ar->arvifs linking with data_lock

[Michal Kazior]

This will make it possible to iterate over
interface list while in an atomic context,
i.e. tasklet.

Caller should still be careful with accessing
arvif structures though.

Signed-off-by: Michal Kazior <michal.kazior at tieto.com>
---
 drivers/net/wireless/ath/ath10k/mac.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index b175827..fed8cc9 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -3283,7 +3283,10 @@ static int ath10k_add_interface(struct ieee80211_hw *hw,
 	}
 
 	ar->free_vdev_map &= ~(1LL << arvif->vdev_id);
+
+	spin_lock_bh(&ar->data_lock);
 	list_add(&arvif->list, &ar->arvifs);
+	spin_unlock_bh(&ar->data_lock);
 
 	vdev_param = ar->wmi.vdev_param->def_keyid;
 	ret = ath10k_wmi_vdev_set_param(ar, 0, vdev_param,
@@ -3400,7 +3403,9 @@ err_peer_delete:
 err_vdev_delete:
 	ath10k_wmi_vdev_delete(ar, arvif->vdev_id);
 	ar->free_vdev_map |= 1LL << arvif->vdev_id;
+	spin_lock_bh(&ar->data_lock);
 	list_del(&arvif->list);
+	spin_unlock_bh(&ar->data_lock);
 
 err:
 	if (arvif->beacon_buf) {
@@ -3435,7 +3440,10 @@ static void ath10k_remove_interface(struct ieee80211_hw *hw,
 			    arvif->vdev_id, ret);
 
 	ar->free_vdev_map |= 1LL << arvif->vdev_id;
+
+	spin_lock_bh(&ar->data_lock);
 	list_del(&arvif->list);
+	spin_unlock_bh(&ar->data_lock);
 
 	if (arvif->vdev_type == WMI_VDEV_TYPE_AP) {
 		ret = ath10k_wmi_peer_delete(arvif->ar, arvif->vdev_id,
-- 
1.8.5.3