[PATCH] mac80211: Allow concurrent monitor iface and ethernet rx decap

[Sriram R <srirrama@codeaurora.org>]

Some HW/driver can support passing ethernet rx decap frames and raw 802.11
frames for the monitor interface concurrently and through separately
calls to ieee80211_rx_napi(). Also packets to monitor interface
doesnt have RX_FLAG_8023 set and can set RX_FLAG_ONLY_MONITOR to
pass them to monitor interface exclusively.
Such drivers can enable the SUPPORTS_CONC_MON_RX_DECAP flag to allow
this using ethernet decap offload while monitor interface is active.

Currently the RX DECAP Offload gets disabled when a monitor
interface is up.

Signed-off-by: Sriram R <srirrama@codeaurora.org>
---
 include/net/mac80211.h | 4 ++++
 net/mac80211/debugfs.c | 1 +
 net/mac80211/iface.c   | 3 ++-
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 2d1d629..6b6901b 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2399,6 +2399,9 @@ struct ieee80211_txq {
  * @IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD: Hardware supports rx decapsulation
  *	offload
  *
+ * @IEEE80211_HW_SUPPORTS_CONC_MON_RX_DECAP: Hardware supports concurrent rx
+ *	decapsulation offload and passing raw 802.11 frames for monitor iface.
+ *
  * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
  */
 enum ieee80211_hw_flags {
@@ -2453,6 +2456,7 @@ enum ieee80211_hw_flags {
 	IEEE80211_HW_AMPDU_KEYBORDER_SUPPORT,
 	IEEE80211_HW_SUPPORTS_TX_ENCAP_OFFLOAD,
 	IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD,
+	IEEE80211_HW_SUPPORTS_CONC_MON_RX_DECAP,
 
 	/* keep last, obviously */
 	NUM_IEEE80211_HW_FLAGS
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 5296898..9245c04 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -456,6 +456,7 @@ static const char *hw_flag_names[] = {
 	FLAG(AMPDU_KEYBORDER_SUPPORT),
 	FLAG(SUPPORTS_TX_ENCAP_OFFLOAD),
 	FLAG(SUPPORTS_RX_DECAP_OFFLOAD),
+	FLAG(SUPPORTS_CONC_MON_RX_DECAP),
 #undef FLAG
 };
 
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index b80c9b0..b1c1709 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -807,7 +807,8 @@ static bool ieee80211_set_sdata_offload_flags(struct ieee80211_sub_if_data *sdat
 	    ieee80211_iftype_supports_hdr_offload(sdata->vif.type)) {
 		flags |= IEEE80211_OFFLOAD_DECAP_ENABLED;
 
-		if (local->monitors)
+		if (local->monitors &&
+		    !ieee80211_hw_check(&local->hw, SUPPORTS_CONC_MON_RX_DECAP))
 			flags &= ~IEEE80211_OFFLOAD_DECAP_ENABLED;
 	} else {
 		flags &= ~IEEE80211_OFFLOAD_DECAP_ENABLED;
-- 
2.7.4