Commit 59ca9572 authored by Johannes Berg's avatar Johannes Berg Committed by Luca Coelho
Browse files

iwlwifi: mvm: use CHECKSUM_COMPLETE 



On newer hardware, we have the full checksum, so use it to report
CHECKSUM_COMPLETE and avoid the protocol specific hardware parsing.

Note that the hardware already parses/removes the SNAP header, so
we actually literally get what we need to report to the stack, as
we're expected to checksum everything after the L2 header (which
is translated/added by mac80211).

Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarLuca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200926002540.869e829c815d.I70f374865b0acafc675a8d7959912eeaeb595acf@changeid


Signed-off-by: default avatarLuca Coelho <luciano.coelho@intel.com>
parent cfa5d0ca

drivers/net/wireless/intel/iwlwifi/fw/api/rx.h

+5 −1
Original line number Diff line number Diff line
@@ -560,7 +560,11 @@ struct iwl_rx_mpdu_desc_v3 { 
	/**

	 * @raw_xsum: raw xsum value

	 */

	__le32 raw_xsum;

	__be16 raw_xsum;

	/**

	 * @reserved_xsum: reserved high bits in the raw checksum

	 */

	__le16 reserved_xsum;

	/* DW11 */

	/**

	 * @rate_n_flags: RX rate/flags encoding

drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c

+56 −17
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ 
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.

 * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH

 * Copyright(c) 2015 - 2017 Intel Deutschland GmbH

 * Copyright(c) 2018 - 2019 Intel Corporation

 * Copyright(c) 2018 - 2020 Intel Corporation

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of version 2 of the GNU General Public License as
@@ -31,7 +31,7 @@ 
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.

 * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH

 * Copyright(c) 2015 - 2017 Intel Deutschland GmbH

 * Copyright(c) 2018 - 2019 Intel Corporation

 * Copyright(c) 2018 - 2020 Intel Corporation

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without
@@ -221,6 +221,31 @@ static int iwl_mvm_create_skb(struct iwl_mvm *mvm, struct sk_buff *skb, 
	skb_put_data(skb, hdr, hdrlen);

	skb_put_data(skb, (u8 *)hdr + hdrlen + pad_len, headlen - hdrlen);



	/*

	 * If we did CHECKSUM_COMPLETE, the hardware only does it right for

	 * certain cases and starts the checksum after the SNAP. Check if

	 * this is the case - it's easier to just bail out to CHECKSUM_NONE

	 * in the cases the hardware didn't handle, since it's rare to see

	 * such packets, even though the hardware did calculate the checksum

	 * in this case, just starting after the MAC header instead.

	 */

	if (skb->ip_summed == CHECKSUM_COMPLETE) {

		struct {

			u8 hdr[6];

			__be16 type;

		} __packed *shdr = (void *)((u8 *)hdr + hdrlen + pad_len);



		if (unlikely(headlen - hdrlen < sizeof(*shdr) ||

			     !ether_addr_equal(shdr->hdr, rfc1042_header) ||

			     (shdr->type != htons(ETH_P_IP) &&

			      shdr->type != htons(ETH_P_ARP) &&

			      shdr->type != htons(ETH_P_IPV6) &&

			      shdr->type != htons(ETH_P_8021Q) &&

			      shdr->type != htons(ETH_P_PAE) &&

			      shdr->type != htons(ETH_P_TDLS))))

			skb->ip_summed = CHECKSUM_NONE;

	}



	fraglen = len - headlen;



	if (fraglen) {
@@ -393,16 +418,29 @@ static int iwl_mvm_rx_crypto(struct iwl_mvm *mvm, struct ieee80211_hdr *hdr, 
	return 0;

}



static void iwl_mvm_rx_csum(struct ieee80211_sta *sta,

static void iwl_mvm_rx_csum(struct iwl_mvm *mvm,

			    struct ieee80211_sta *sta,

			    struct sk_buff *skb,

			    struct iwl_rx_mpdu_desc *desc)

			    struct iwl_rx_packet *pkt)

{

	struct iwl_rx_mpdu_desc *desc = (void *)pkt->data;



	if (mvm->trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {

		if (pkt->len_n_flags & cpu_to_le32(FH_RSCSR_RPA_EN)) {

			u16 hwsum = be16_to_cpu(desc->v3.raw_xsum);



			skb->ip_summed = CHECKSUM_COMPLETE;

			skb->csum = csum_unfold(~(__force __sum16)hwsum);

		}

	} else {

		struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);

	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(mvmsta->vif);

		struct iwl_mvm_vif *mvmvif;

		u16 flags = le16_to_cpu(desc->l3l4_flags);

		u8 l3_prot = (u8)((flags & IWL_RX_L3L4_L3_PROTO_MASK) >>

				  IWL_RX_L3_PROTO_POS);



		mvmvif = iwl_mvm_vif_from_mac80211(mvmsta->vif);



		if (mvmvif->features & NETIF_F_RXCSUM &&

		    flags & IWL_RX_L3L4_TCP_UDP_CSUM_OK &&

		    (flags & IWL_RX_L3L4_IP_HDR_CSUM_OK ||
@@ -410,6 +448,7 @@ static void iwl_mvm_rx_csum(struct ieee80211_sta *sta, 
		     l3_prot == IWL_RX_L3_TYPE_IPV6_FRAG))

			skb->ip_summed = CHECKSUM_UNNECESSARY;

	}

}



/*

 * returns true if a packet is a duplicate and should be dropped.
@@ -1796,7 +1835,7 @@ void iwl_mvm_rx_mpdu_mq(struct iwl_mvm *mvm, struct napi_struct *napi, 
		}



		if (ieee80211_is_data(hdr->frame_control))

			iwl_mvm_rx_csum(sta, skb, desc);

			iwl_mvm_rx_csum(mvm, sta, skb, pkt);



		if (iwl_mvm_is_dup(sta, queue, rx_status, hdr, desc)) {

			kfree_skb(skb);