mac80211: add performance improvements for A-MSDU rx

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 48630

3 files changed, 380 insertions, 0 deletions

diff --git a/package/kernel/mac80211/patches/318-mac80211-move-A-MSDU-skb_linearize-call-to-ieee80211.patch b/package/kernel/mac80211/patches/318-mac80211-move-A-MSDU-skb_linearize-call-to-ieee80211.patch
new file mode 100644
index 0000000000..655dc4bfa9
--- /dev/null
+++ b/package/kernel/mac80211/patches/318-mac80211-move-A-MSDU-skb_linearize-call-to-ieee80211.patch
@@ -0,0 +1,35 @@
+From: Felix Fietkau <nbd@openwrt.org>
+Date: Tue, 2 Feb 2016 14:39:08 +0100
+Subject: [PATCH] mac80211: move A-MSDU skb_linearize call to
+ ieee80211_amsdu_to_8023s
+
+Prepararation for zero-copy A-MSDU support with page fragment SKBs
+
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+---
+
+--- a/net/mac80211/rx.c
++++ b/net/mac80211/rx.c
+@@ -2203,9 +2203,6 @@ ieee80211_rx_h_amsdu(struct ieee80211_rx
+ 	skb->dev = dev;
+ 	__skb_queue_head_init(&frame_list);
+ 
+-	if (skb_linearize(skb))
+-		return RX_DROP_UNUSABLE;
+-
+ 	ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
+ 				 rx->sdata->vif.type,
+ 				 rx->local->hw.extra_tx_headroom, true);
+--- a/net/wireless/util.c
++++ b/net/wireless/util.c
+@@ -657,6 +657,9 @@ void ieee80211_amsdu_to_8023s(struct sk_
+ 	int remaining, err;
+ 	u8 dst[ETH_ALEN], src[ETH_ALEN];
+ 
++	if (skb_linearize(skb))
++		goto out;
++
+ 	if (has_80211_header) {
+ 		err = ieee80211_data_to_8023(skb, addr, iftype);
+ 		if (err)
diff --git a/package/kernel/mac80211/patches/319-cfg80211-add-function-for-802.3-conversion-with-sepa.patch b/package/kernel/mac80211/patches/319-cfg80211-add-function-for-802.3-conversion-with-sepa.patch
new file mode 100644
index 0000000000..b646ab36dd
--- /dev/null
+++ b/package/kernel/mac80211/patches/319-cfg80211-add-function-for-802.3-conversion-with-sepa.patch
@@ -0,0 +1,186 @@
+From: Felix Fietkau <nbd@openwrt.org>
+Date: Tue, 2 Feb 2016 14:39:09 +0100
+Subject: [PATCH] cfg80211: add function for 802.3 conversion with separate
+ output buffer
+
+Use skb_copy_bits in preparation for allowing fragmented skbs
+
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+---
+
+--- a/net/wireless/util.c
++++ b/net/wireless/util.c
+@@ -393,9 +393,9 @@ unsigned int ieee80211_get_hdrlen_from_s
+ }
+ EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
+ 
+-unsigned int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
++static unsigned int __ieee80211_get_mesh_hdrlen(u8 flags)
+ {
+-	int ae = meshhdr->flags & MESH_FLAGS_AE;
++	int ae = flags & MESH_FLAGS_AE;
+ 	/* 802.11-2012, 8.2.4.7.3 */
+ 	switch (ae) {
+ 	default:
+@@ -407,21 +407,31 @@ unsigned int ieee80211_get_mesh_hdrlen(s
+ 		return 18;
+ 	}
+ }
++
++unsigned int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
++{
++	return __ieee80211_get_mesh_hdrlen(meshhdr->flags);
++}
+ EXPORT_SYMBOL(ieee80211_get_mesh_hdrlen);
+ 
+-int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
+-			   enum nl80211_iftype iftype)
++static int __ieee80211_data_to_8023(struct sk_buff *skb, struct ethhdr *ehdr,
++				    const u8 *addr, enum nl80211_iftype iftype)
+ {
+ 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+-	u16 hdrlen, ethertype;
+-	u8 *payload;
+-	u8 dst[ETH_ALEN];
+-	u8 src[ETH_ALEN] __aligned(2);
++	struct {
++		u8 hdr[ETH_ALEN] __aligned(2);
++		__be16 proto;
++	} payload;
++	struct ethhdr tmp;
++	u16 hdrlen;
++	u8 mesh_flags = 0;
+ 
+ 	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
+ 		return -1;
+ 
+ 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
++	if (skb->len < hdrlen + 8)
++		return -1;
+ 
+ 	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
+ 	 * header
+@@ -432,8 +442,11 @@ int ieee80211_data_to_8023(struct sk_buf
+ 	 *   1     0   BSSID SA    DA    n/a
+ 	 *   1     1   RA    TA    DA    SA
+ 	 */
+-	memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
+-	memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
++	memcpy(tmp.h_dest, ieee80211_get_DA(hdr), ETH_ALEN);
++	memcpy(tmp.h_source, ieee80211_get_SA(hdr), ETH_ALEN);
++
++	if (iftype == NL80211_IFTYPE_MESH_POINT)
++		skb_copy_bits(skb, hdrlen, &mesh_flags, 1);
+ 
+ 	switch (hdr->frame_control &
+ 		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
+@@ -450,44 +463,31 @@ int ieee80211_data_to_8023(struct sk_buf
+ 			     iftype != NL80211_IFTYPE_STATION))
+ 			return -1;
+ 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
+-			struct ieee80211s_hdr *meshdr =
+-				(struct ieee80211s_hdr *) (skb->data + hdrlen);
+-			/* make sure meshdr->flags is on the linear part */
+-			if (!pskb_may_pull(skb, hdrlen + 1))
+-				return -1;
+-			if (meshdr->flags & MESH_FLAGS_AE_A4)
++			if (mesh_flags & MESH_FLAGS_AE_A4)
+ 				return -1;
+-			if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
++			if (mesh_flags & MESH_FLAGS_AE_A5_A6) {
+ 				skb_copy_bits(skb, hdrlen +
+ 					offsetof(struct ieee80211s_hdr, eaddr1),
+-				       	dst, ETH_ALEN);
+-				skb_copy_bits(skb, hdrlen +
+-					offsetof(struct ieee80211s_hdr, eaddr2),
+-				        src, ETH_ALEN);
++					tmp.h_dest, 2 * ETH_ALEN);
+ 			}
+-			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
++			hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags);
+ 		}
+ 		break;
+ 	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
+ 		if ((iftype != NL80211_IFTYPE_STATION &&
+ 		     iftype != NL80211_IFTYPE_P2P_CLIENT &&
+ 		     iftype != NL80211_IFTYPE_MESH_POINT) ||
+-		    (is_multicast_ether_addr(dst) &&
+-		     ether_addr_equal(src, addr)))
++		    (is_multicast_ether_addr(tmp.h_dest) &&
++		     ether_addr_equal(tmp.h_source, addr)))
+ 			return -1;
+ 		if (iftype == NL80211_IFTYPE_MESH_POINT) {
+-			struct ieee80211s_hdr *meshdr =
+-				(struct ieee80211s_hdr *) (skb->data + hdrlen);
+-			/* make sure meshdr->flags is on the linear part */
+-			if (!pskb_may_pull(skb, hdrlen + 1))
+-				return -1;
+-			if (meshdr->flags & MESH_FLAGS_AE_A5_A6)
++			if (mesh_flags & MESH_FLAGS_AE_A5_A6)
+ 				return -1;
+-			if (meshdr->flags & MESH_FLAGS_AE_A4)
++			if (mesh_flags & MESH_FLAGS_AE_A4)
+ 				skb_copy_bits(skb, hdrlen +
+ 					offsetof(struct ieee80211s_hdr, eaddr1),
+-					src, ETH_ALEN);
+-			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
++					tmp.h_source, ETH_ALEN);
++			hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags);
+ 		}
+ 		break;
+ 	case cpu_to_le16(0):
+@@ -498,33 +498,33 @@ int ieee80211_data_to_8023(struct sk_buf
+ 		break;
+ 	}
+ 
+-	if (!pskb_may_pull(skb, hdrlen + 8))
+-		return -1;
+-
+-	payload = skb->data + hdrlen;
+-	ethertype = (payload[6] << 8) | payload[7];
++	skb_copy_bits(skb, hdrlen, &payload, sizeof(payload));
++	tmp.h_proto = payload.proto;
+ 
+-	if (likely((ether_addr_equal(payload, rfc1042_header) &&
+-		    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
+-		   ether_addr_equal(payload, bridge_tunnel_header))) {
++	if (likely((ether_addr_equal(payload.hdr, rfc1042_header) &&
++		    tmp.h_proto != htons(ETH_P_AARP) &&
++		    tmp.h_proto != htons(ETH_P_IPX)) ||
++		   ether_addr_equal(payload.hdr, bridge_tunnel_header)))
+ 		/* remove RFC1042 or Bridge-Tunnel encapsulation and
+ 		 * replace EtherType */
+-		skb_pull(skb, hdrlen + 6);
+-		memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
+-		memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
+-	} else {
+-		struct ethhdr *ehdr;
+-		__be16 len;
++		hdrlen += ETH_ALEN + 2;
++	else
++		tmp.h_proto = htons(skb->len);
+ 
+-		skb_pull(skb, hdrlen);
+-		len = htons(skb->len);
++	pskb_pull(skb, hdrlen);
++
++	if (!ehdr)
+ 		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
+-		memcpy(ehdr->h_dest, dst, ETH_ALEN);
+-		memcpy(ehdr->h_source, src, ETH_ALEN);
+-		ehdr->h_proto = len;
+-	}
++	memcpy(ehdr, &tmp, sizeof(tmp));
++
+ 	return 0;
+ }
++
++int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
++			   enum nl80211_iftype iftype)
++{
++	return __ieee80211_data_to_8023(skb, NULL, addr, iftype);
++}
+ EXPORT_SYMBOL(ieee80211_data_to_8023);
+ 
+ int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
diff --git a/package/kernel/mac80211/patches/320-cfg80211-add-support-for-non-linear-skbs-in-ieee8021.patch b/package/kernel/mac80211/patches/320-cfg80211-add-support-for-non-linear-skbs-in-ieee8021.patch
new file mode 100644
index 0000000000..2eeed22af0
--- /dev/null
+++ b/package/kernel/mac80211/patches/320-cfg80211-add-support-for-non-linear-skbs-in-ieee8021.patch
@@ -0,0 +1,159 @@
+From: Felix Fietkau <nbd@openwrt.org>
+Date: Tue, 2 Feb 2016 14:39:10 +0100
+Subject: [PATCH] cfg80211: add support for non-linear skbs in
+ ieee80211_amsdu_to_8023s
+
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+---
+
+--- a/net/wireless/util.c
++++ b/net/wireless/util.c
+@@ -644,73 +644,75 @@ int ieee80211_data_from_8023(struct sk_b
+ }
+ EXPORT_SYMBOL(ieee80211_data_from_8023);
+ 
++static struct sk_buff *
++__ieee80211_amsdu_copy(struct sk_buff *skb, unsigned int hlen,
++		       int offset, int len)
++{
++	struct sk_buff *frame;
++
++	if (skb->len - offset < len)
++		return NULL;
++
++	/*
++	 * Allocate and reserve two bytes more for payload
++	 * alignment since sizeof(struct ethhdr) is 14.
++	 */
++	frame = dev_alloc_skb(hlen + sizeof(struct ethhdr) + 2 + len);
++
++	skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
++	skb_copy_bits(skb, offset, skb_put(frame, len), len);
++
++	return frame;
++}
+ 
+ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
+ 			      const u8 *addr, enum nl80211_iftype iftype,
+ 			      const unsigned int extra_headroom,
+ 			      bool has_80211_header)
+ {
++	unsigned int hlen = ALIGN(extra_headroom, 4);
+ 	struct sk_buff *frame = NULL;
+ 	u16 ethertype;
+ 	u8 *payload;
+-	const struct ethhdr *eth;
+-	int remaining, err;
+-	u8 dst[ETH_ALEN], src[ETH_ALEN];
+-
+-	if (skb_linearize(skb))
+-		goto out;
++	int offset = 0, remaining, err;
++	struct ethhdr eth;
++	bool reuse_skb = true;
++	bool last = false;
+ 
+ 	if (has_80211_header) {
+-		err = ieee80211_data_to_8023(skb, addr, iftype);
++		err = __ieee80211_data_to_8023(skb, &eth, addr, iftype);
+ 		if (err)
+ 			goto out;
+-
+-		/* skip the wrapping header */
+-		eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
+-		if (!eth)
+-			goto out;
+-	} else {
+-		eth = (struct ethhdr *) skb->data;
+ 	}
+ 
+-	while (skb != frame) {
++	while (!last) {
++		unsigned int subframe_len;
++		int len;
+ 		u8 padding;
+-		__be16 len = eth->h_proto;
+-		unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
+-
+-		remaining = skb->len;
+-		memcpy(dst, eth->h_dest, ETH_ALEN);
+-		memcpy(src, eth->h_source, ETH_ALEN);
+ 
++		skb_copy_bits(skb, offset, &eth, sizeof(eth));
++		len = ntohs(eth.h_proto);
++		subframe_len = sizeof(struct ethhdr) + len;
+ 		padding = (4 - subframe_len) & 0x3;
++
+ 		/* the last MSDU has no padding */
++		remaining = skb->len - offset;
+ 		if (subframe_len > remaining)
+ 			goto purge;
+ 
+-		skb_pull(skb, sizeof(struct ethhdr));
++		offset += sizeof(struct ethhdr);
+ 		/* reuse skb for the last subframe */
+-		if (remaining <= subframe_len + padding)
++		last = remaining <= subframe_len + padding;
++		if (!skb_is_nonlinear(skb) && last) {
++			skb_pull(skb, offset);
+ 			frame = skb;
+-		else {
+-			unsigned int hlen = ALIGN(extra_headroom, 4);
+-			/*
+-			 * Allocate and reserve two bytes more for payload
+-			 * alignment since sizeof(struct ethhdr) is 14.
+-			 */
+-			frame = dev_alloc_skb(hlen + subframe_len + 2);
++			reuse_skb = true;
++		} else {
++			frame = __ieee80211_amsdu_copy(skb, hlen, offset, len);
+ 			if (!frame)
+ 				goto purge;
+ 
+-			skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
+-			memcpy(skb_put(frame, ntohs(len)), skb->data,
+-				ntohs(len));
+-
+-			eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
+-							padding);
+-			if (!eth) {
+-				dev_kfree_skb(frame);
+-				goto purge;
+-			}
++			offset += len + padding;
+ 		}
+ 
+ 		skb_reset_network_header(frame);
+@@ -719,24 +721,20 @@ void ieee80211_amsdu_to_8023s(struct sk_
+ 
+ 		payload = frame->data;
+ 		ethertype = (payload[6] << 8) | payload[7];
+-
+ 		if (likely((ether_addr_equal(payload, rfc1042_header) &&
+ 			    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
+ 			   ether_addr_equal(payload, bridge_tunnel_header))) {
+-			/* remove RFC1042 or Bridge-Tunnel
+-			 * encapsulation and replace EtherType */
+-			skb_pull(frame, 6);
+-			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
+-			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
+-		} else {
+-			memcpy(skb_push(frame, sizeof(__be16)), &len,
+-				sizeof(__be16));
+-			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
+-			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
++			eth.h_proto = htons(ethertype);
++			skb_pull(frame, ETH_ALEN + 2);
+ 		}
++
++		memcpy(skb_push(frame, sizeof(eth)), &eth, sizeof(eth));
+ 		__skb_queue_tail(list, frame);
+ 	}
+ 
++	if (!reuse_skb)
++		dev_kfree_skb(skb);
++
+ 	return;
+ 
+  purge: