Commit 80a915ec authored by Felix Fietkau's avatar Felix Fietkau Committed by Johannes Berg
Browse files

mac80211: add rx decapsulation offload support 



This allows drivers to pass 802.3 frames to mac80211, with some restrictions:

- the skb must be passed with a valid sta
- fast-rx needs to be active for the sta
- monitor mode needs to be disabled

mac80211 will tell the driver when it is safe to enable rx decap offload for
a particular station.

In order to implement support, a driver must:

- call ieee80211_hw_set(hw, SUPPORTS_RX_DECAP_OFFLOAD)
- implement ops->sta_set_decap_offload
- mark 802.3 frames with RX_FLAG_8023

If it doesn't want to enable offload for some vif types, it can mask out
IEEE80211_OFFLOAD_DECAP_ENABLED in vif->offload_flags from within the
.add_interface or .update_vif_offload driver ops

Signed-off-by: default avatarFelix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20201218184718.93650-6-nbd@nbd.name


Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent d7b64929

include/net/mac80211.h

+16 −0
Original line number Diff line number Diff line
@@ -1296,6 +1296,8 @@ ieee80211_tx_info_clear_status(struct ieee80211_tx_info *info) 
 *	the "0-length PSDU" field included there.  The value for it is

 *	in &struct ieee80211_rx_status.  Note that if this value isn't

 *	known the frame shouldn't be reported.

 * @RX_FLAG_8023: the frame has an 802.3 header (decap offload performed by

 *	hardware or driver)

 */

enum mac80211_rx_flags {

	RX_FLAG_MMIC_ERROR		= BIT(0),
@@ -1328,6 +1330,7 @@ enum mac80211_rx_flags { 
	RX_FLAG_RADIOTAP_HE_MU		= BIT(27),

	RX_FLAG_RADIOTAP_LSIG		= BIT(28),

	RX_FLAG_NO_PSDU			= BIT(29),

	RX_FLAG_8023			= BIT(30),

};



/**
@@ -1649,11 +1652,15 @@ enum ieee80211_vif_flags { 
 *	The driver supports sending frames passed as 802.3 frames by mac80211.

 *	It must also support sending 802.11 packets for the same interface.

 * @IEEE80211_OFFLOAD_ENCAP_4ADDR: support 4-address mode encapsulation offload

 * @IEEE80211_OFFLOAD_DECAP_ENABLED: rx encapsulation offload is enabled

 *	The driver supports passing received 802.11 frames as 802.3 frames to

 *	mac80211.

 */



enum ieee80211_offload_flags {

	IEEE80211_OFFLOAD_ENCAP_ENABLED		= BIT(0),

	IEEE80211_OFFLOAD_ENCAP_4ADDR		= BIT(1),

	IEEE80211_OFFLOAD_DECAP_ENABLED		= BIT(2),

};



/**
@@ -2389,6 +2396,9 @@ struct ieee80211_txq { 
 * @IEEE80211_HW_SUPPORTS_TX_ENCAP_OFFLOAD: Hardware supports tx encapsulation

 *	offload

 *

 * @IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD: Hardware supports rx decapsulation

 *	offload

 *

 * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays

 */

enum ieee80211_hw_flags {
@@ -2442,6 +2452,7 @@ enum ieee80211_hw_flags { 
	IEEE80211_HW_SUPPORTS_ONLY_HE_MULTI_BSSID,

	IEEE80211_HW_AMPDU_KEYBORDER_SUPPORT,

	IEEE80211_HW_SUPPORTS_TX_ENCAP_OFFLOAD,

	IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD,



	/* keep last, obviously */

	NUM_IEEE80211_HW_FLAGS
@@ -3881,6 +3892,8 @@ enum ieee80211_reconfig_type { 
 * @sta_set_4addr: Called to notify the driver when a station starts/stops using

 *	4-address mode

 * @set_sar_specs: Update the SAR (TX power) settings.

 * @sta_set_decap_offload: Called to notify the driver when a station is allowed

 *	to use rx decapsulation offload

 */

struct ieee80211_ops {

	void (*tx)(struct ieee80211_hw *hw,
@@ -4198,6 +4211,9 @@ struct ieee80211_ops { 
			      struct ieee80211_sta *sta, bool enabled);

	int (*set_sar_specs)(struct ieee80211_hw *hw,

			     const struct cfg80211_sar_specs *sar);

	void (*sta_set_decap_offload)(struct ieee80211_hw *hw,

				      struct ieee80211_vif *vif,

				      struct ieee80211_sta *sta, bool enabled);

};



/**

net/mac80211/debugfs.c

+1 −0
Original line number Diff line number Diff line
@@ -405,6 +405,7 @@ static const char *hw_flag_names[] = { 
	FLAG(SUPPORTS_ONLY_HE_MULTI_BSSID),

	FLAG(AMPDU_KEYBORDER_SUPPORT),

	FLAG(SUPPORTS_TX_ENCAP_OFFLOAD),

	FLAG(SUPPORTS_RX_DECAP_OFFLOAD),

#undef FLAG

};

net/mac80211/debugfs_sta.c

+1 −0
Original line number Diff line number Diff line
@@ -79,6 +79,7 @@ static const char * const sta_flag_names[] = { 
	FLAG(MPSP_RECIPIENT),

	FLAG(PS_DELIVER),

	FLAG(USES_ENCRYPTION),

	FLAG(DECAP_OFFLOAD),

#undef FLAG

};

net/mac80211/driver-ops.h

+16 −0
Original line number Diff line number Diff line
@@ -1413,4 +1413,20 @@ static inline void drv_sta_set_4addr(struct ieee80211_local *local, 
	trace_drv_return_void(local);

}



static inline void drv_sta_set_decap_offload(struct ieee80211_local *local,

					     struct ieee80211_sub_if_data *sdata,

					     struct ieee80211_sta *sta,

					     bool enabled)

{

	sdata = get_bss_sdata(sdata);

	if (!check_sdata_in_driver(sdata))

		return;



	trace_drv_sta_set_decap_offload(local, sdata, sta, enabled);

	if (local->ops->sta_set_decap_offload)

		local->ops->sta_set_decap_offload(&local->hw, &sdata->vif, sta,

						  enabled);

	trace_drv_return_void(local);

}



#endif /* __MAC80211_DRIVER_OPS */

net/mac80211/iface.c

+14 −3
Original line number Diff line number Diff line
@@ -765,7 +765,7 @@ static const struct net_device_ops ieee80211_dataif_8023_ops = { 
	.ndo_get_stats64	= ieee80211_get_stats64,

};



static bool ieee80211_iftype_supports_encap_offload(enum nl80211_iftype iftype)

static bool ieee80211_iftype_supports_hdr_offload(enum nl80211_iftype iftype)

{

	switch (iftype) {

	/* P2P GO and client are mapped to AP/STATION types */
@@ -785,7 +785,7 @@ static bool ieee80211_set_sdata_offload_flags(struct ieee80211_sub_if_data *sdat 
	flags = sdata->vif.offload_flags;



	if (ieee80211_hw_check(&local->hw, SUPPORTS_TX_ENCAP_OFFLOAD) &&

	    ieee80211_iftype_supports_encap_offload(sdata->vif.type)) {

	    ieee80211_iftype_supports_hdr_offload(sdata->vif.type)) {

		flags |= IEEE80211_OFFLOAD_ENCAP_ENABLED;



		if (!ieee80211_hw_check(&local->hw, SUPPORTS_TX_FRAG) &&
@@ -798,10 +798,21 @@ static bool ieee80211_set_sdata_offload_flags(struct ieee80211_sub_if_data *sdat 
		flags &= ~IEEE80211_OFFLOAD_ENCAP_ENABLED;

	}



	if (ieee80211_hw_check(&local->hw, SUPPORTS_RX_DECAP_OFFLOAD) &&

	    ieee80211_iftype_supports_hdr_offload(sdata->vif.type)) {

		flags |= IEEE80211_OFFLOAD_DECAP_ENABLED;



		if (local->monitors)

			flags &= ~IEEE80211_OFFLOAD_DECAP_ENABLED;

	} else {

		flags &= ~IEEE80211_OFFLOAD_DECAP_ENABLED;

	}



	if (sdata->vif.offload_flags == flags)

		return false;



	sdata->vif.offload_flags = flags;

	ieee80211_check_fast_rx_iface(sdata);

	return true;

}
@@ -819,7 +830,7 @@ static void ieee80211_set_vif_encap_ops(struct ieee80211_sub_if_data *sdata) 
	}



	if (!ieee80211_hw_check(&local->hw, SUPPORTS_TX_ENCAP_OFFLOAD) ||

	    !ieee80211_iftype_supports_encap_offload(bss->vif.type))

	    !ieee80211_iftype_supports_hdr_offload(bss->vif.type))

		return;



	enabled = bss->vif.offload_flags & IEEE80211_OFFLOAD_ENCAP_ENABLED;