Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 175 insertions, 102 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 92770427b211..9f440a9de63b 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -393,9 +393,9 @@ unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 }
 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(struct ieee80211s_hdr *meshhdr)
 		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_buff *skb, const u8 *addr,
 	 *   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_buff *skb, const u8 *addr,
 			     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_buff *skb, const u8 *addr,
 		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,
@@ -636,7 +636,7 @@ int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 	/* Update skb pointers to various headers since this modified frame
 	 * is going to go through Linux networking code that may potentially
 	 * need things like pointer to IP header. */
-	skb_set_mac_header(skb, 0);
+	skb_reset_mac_header(skb);
 	skb_set_network_header(skb, nh_pos);
 	skb_set_transport_header(skb, h_pos);
 
@@ -644,70 +644,147 @@ int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 }
 EXPORT_SYMBOL(ieee80211_data_from_8023);
 
+static void
+__frame_add_frag(struct sk_buff *skb, struct page *page,
+		 void *ptr, int len, int size)
+{
+	struct skb_shared_info *sh = skb_shinfo(skb);
+	int page_offset;
+
+	atomic_inc(&page->_count);
+	page_offset = ptr - page_address(page);
+	skb_add_rx_frag(skb, sh->nr_frags, page, page_offset, len, size);
+}
+
+static void
+__ieee80211_amsdu_copy_frag(struct sk_buff *skb, struct sk_buff *frame,
+			    int offset, int len)
+{
+	struct skb_shared_info *sh = skb_shinfo(skb);
+	const skb_frag_t *frag = &sh->frags[-1];
+	struct page *frag_page;
+	void *frag_ptr;
+	int frag_len, frag_size;
+	int head_size = skb->len - skb->data_len;
+	int cur_len;
+
+	frag_page = virt_to_head_page(skb->head);
+	frag_ptr = skb->data;
+	frag_size = head_size;
+
+	while (offset >= frag_size) {
+		offset -= frag_size;
+		frag++;
+		frag_page = skb_frag_page(frag);
+		frag_ptr = skb_frag_address(frag);
+		frag_size = skb_frag_size(frag);
+	}
+
+	frag_ptr += offset;
+	frag_len = frag_size - offset;
+
+	cur_len = min(len, frag_len);
+
+	__frame_add_frag(frame, frag_page, frag_ptr, cur_len, frag_size);
+	len -= cur_len;
+
+	while (len > 0) {
+		frag++;
+		frag_len = skb_frag_size(frag);
+		cur_len = min(len, frag_len);
+		__frame_add_frag(frame, skb_frag_page(frag),
+				 skb_frag_address(frag), cur_len, frag_len);
+		len -= cur_len;
+	}
+}
+
+static struct sk_buff *
+__ieee80211_amsdu_copy(struct sk_buff *skb, unsigned int hlen,
+		       int offset, int len, bool reuse_frag)
+{
+	struct sk_buff *frame;
+	int cur_len = len;
+
+	if (skb->len - offset < len)
+		return NULL;
+
+	/*
+	 * When reusing framents, copy some data to the head to simplify
+	 * ethernet header handling and speed up protocol header processing
+	 * in the stack later.
+	 */
+	if (reuse_frag)
+		cur_len = min_t(int, len, 32);
+
+	/*
+	 * Allocate and reserve two bytes more for payload
+	 * alignment since sizeof(struct ethhdr) is 14.
+	 */
+	frame = dev_alloc_skb(hlen + sizeof(struct ethhdr) + 2 + cur_len);
+
+	skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
+	skb_copy_bits(skb, offset, skb_put(frame, cur_len), cur_len);
+
+	len -= cur_len;
+	if (!len)
+		return frame;
+
+	offset += cur_len;
+	__ieee80211_amsdu_copy_frag(skb, frame, offset, 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];
+	int offset = 0, remaining, err;
+	struct ethhdr eth;
+	bool reuse_frag = skb->head_frag && !skb_has_frag_list(skb);
+	bool reuse_skb = false;
+	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) && !reuse_frag && 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,
+						       reuse_frag);
 			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);
@@ -716,24 +793,20 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
 
 		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: