File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/net/wireless/mwifiex/uap_txrx.c b/drivers/net/wireless/mwifiex/uap_txrx.c
new file mode 100644
index 0000000..74d5d72
--- /dev/null
+++ b/drivers/net/wireless/mwifiex/uap_txrx.c
@@ -0,0 +1,437 @@
+/*
+ * Marvell Wireless LAN device driver: AP TX and RX data handling
+ *
+ * Copyright (C) 2012-2014, Marvell International Ltd.
+ *
+ * This software file (the "File") is distributed by Marvell International
+ * Ltd. under the terms of the GNU General Public License Version 2, June 1991
+ * (the "License").  You may use, redistribute and/or modify this File in
+ * accordance with the terms and conditions of the License, a copy of which
+ * is available by writing to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or on the
+ * worldwide web at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
+ *
+ * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
+ * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
+ * this warranty disclaimer.
+ */
+
+#include "decl.h"
+#include "ioctl.h"
+#include "main.h"
+#include "wmm.h"
+#include "11n_aggr.h"
+#include "11n_rxreorder.h"
+
+/* This function checks if particular RA list has packets more than low bridge
+ * packet threshold and then deletes packet from this RA list.
+ * Function deletes packets from such RA list and returns true. If no such list
+ * is found, false is returned.
+ */
+static bool
+mwifiex_uap_del_tx_pkts_in_ralist(struct mwifiex_private *priv,
+				  struct list_head *ra_list_head,
+				  int tid)
+{
+	struct mwifiex_ra_list_tbl *ra_list;
+	struct sk_buff *skb, *tmp;
+	bool pkt_deleted = false;
+	struct mwifiex_txinfo *tx_info;
+	struct mwifiex_adapter *adapter = priv->adapter;
+
+	list_for_each_entry(ra_list, ra_list_head, list) {
+		if (skb_queue_empty(&ra_list->skb_head))
+			continue;
+
+		skb_queue_walk_safe(&ra_list->skb_head, skb, tmp) {
+			tx_info = MWIFIEX_SKB_TXCB(skb);
+			if (tx_info->flags & MWIFIEX_BUF_FLAG_BRIDGED_PKT) {
+				__skb_unlink(skb, &ra_list->skb_head);
+				mwifiex_write_data_complete(adapter, skb, 0,
+							    -1);
+				if (ra_list->tx_paused)
+					priv->wmm.pkts_paused[tid]--;
+				else
+					atomic_dec(&priv->wmm.tx_pkts_queued);
+				pkt_deleted = true;
+			}
+			if ((atomic_read(&adapter->pending_bridged_pkts) <=
+					     MWIFIEX_BRIDGED_PKTS_THR_LOW))
+				break;
+		}
+	}
+
+	return pkt_deleted;
+}
+
+/* This function deletes packets from particular RA List. RA list index
+ * from which packets are deleted is preserved so that packets from next RA
+ * list are deleted upon subsequent call thus maintaining fairness.
+ */
+static void mwifiex_uap_cleanup_tx_queues(struct mwifiex_private *priv)
+{
+	unsigned long flags;
+	struct list_head *ra_list;
+	int i;
+
+	spin_lock_irqsave(&priv->wmm.ra_list_spinlock, flags);
+
+	for (i = 0; i < MAX_NUM_TID; i++, priv->del_list_idx++) {
+		if (priv->del_list_idx == MAX_NUM_TID)
+			priv->del_list_idx = 0;
+		ra_list = &priv->wmm.tid_tbl_ptr[priv->del_list_idx].ra_list;
+		if (mwifiex_uap_del_tx_pkts_in_ralist(priv, ra_list, i)) {
+			priv->del_list_idx++;
+			break;
+		}
+	}
+
+	spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, flags);
+}
+
+
+static void mwifiex_uap_queue_bridged_pkt(struct mwifiex_private *priv,
+					 struct sk_buff *skb)
+{
+	struct mwifiex_adapter *adapter = priv->adapter;
+	struct uap_rxpd *uap_rx_pd;
+	struct rx_packet_hdr *rx_pkt_hdr;
+	struct sk_buff *new_skb;
+	struct mwifiex_txinfo *tx_info;
+	int hdr_chop;
+	struct ethhdr *p_ethhdr;
+	struct mwifiex_sta_node *src_node;
+
+	uap_rx_pd = (struct uap_rxpd *)(skb->data);
+	rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
+
+	if ((atomic_read(&adapter->pending_bridged_pkts) >=
+					     MWIFIEX_BRIDGED_PKTS_THR_HIGH)) {
+		mwifiex_dbg(priv->adapter, ERROR,
+			    "Tx: Bridge packet limit reached. Drop packet!\n");
+		kfree_skb(skb);
+		mwifiex_uap_cleanup_tx_queues(priv);
+		return;
+	}
+
+	if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
+		     sizeof(bridge_tunnel_header))) ||
+	    (!memcmp(&rx_pkt_hdr->rfc1042_hdr, rfc1042_header,
+		     sizeof(rfc1042_header)) &&
+	     ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_AARP &&
+	     ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_IPX)) {
+		/* Replace the 803 header and rfc1042 header (llc/snap) with
+		 * an Ethernet II header, keep the src/dst and snap_type
+		 * (ethertype).
+		 *
+		 * The firmware only passes up SNAP frames converting all RX
+		 * data from 802.11 to 802.2/LLC/SNAP frames.
+		 *
+		 * To create the Ethernet II, just move the src, dst address
+		 * right before the snap_type.
+		 */
+		p_ethhdr = (struct ethhdr *)
+			((u8 *)(&rx_pkt_hdr->eth803_hdr)
+			 + sizeof(rx_pkt_hdr->eth803_hdr)
+			 + sizeof(rx_pkt_hdr->rfc1042_hdr)
+			 - sizeof(rx_pkt_hdr->eth803_hdr.h_dest)
+			 - sizeof(rx_pkt_hdr->eth803_hdr.h_source)
+			 - sizeof(rx_pkt_hdr->rfc1042_hdr.snap_type));
+		memcpy(p_ethhdr->h_source, rx_pkt_hdr->eth803_hdr.h_source,
+		       sizeof(p_ethhdr->h_source));
+		memcpy(p_ethhdr->h_dest, rx_pkt_hdr->eth803_hdr.h_dest,
+		       sizeof(p_ethhdr->h_dest));
+		/* Chop off the rxpd + the excess memory from
+		 * 802.2/llc/snap header that was removed.
+		 */
+		hdr_chop = (u8 *)p_ethhdr - (u8 *)uap_rx_pd;
+	} else {
+		/* Chop off the rxpd */
+		hdr_chop = (u8 *)&rx_pkt_hdr->eth803_hdr - (u8 *)uap_rx_pd;
+	}
+
+	/* Chop off the leading header bytes so that it points
+	 * to the start of either the reconstructed EthII frame
+	 * or the 802.2/llc/snap frame.
+	 */
+	skb_pull(skb, hdr_chop);
+
+	if (skb_headroom(skb) < MWIFIEX_MIN_DATA_HEADER_LEN) {
+		mwifiex_dbg(priv->adapter, ERROR,
+			    "data: Tx: insufficient skb headroom %d\n",
+			    skb_headroom(skb));
+		/* Insufficient skb headroom - allocate a new skb */
+		new_skb =
+			skb_realloc_headroom(skb, MWIFIEX_MIN_DATA_HEADER_LEN);
+		if (unlikely(!new_skb)) {
+			mwifiex_dbg(priv->adapter, ERROR,
+				    "Tx: cannot allocate new_skb\n");
+			kfree_skb(skb);
+			priv->stats.tx_dropped++;
+			return;
+		}
+
+		kfree_skb(skb);
+		skb = new_skb;
+		mwifiex_dbg(priv->adapter, INFO,
+			    "info: new skb headroom %d\n",
+			    skb_headroom(skb));
+	}
+
+	tx_info = MWIFIEX_SKB_TXCB(skb);
+	memset(tx_info, 0, sizeof(*tx_info));
+	tx_info->bss_num = priv->bss_num;
+	tx_info->bss_type = priv->bss_type;
+	tx_info->flags |= MWIFIEX_BUF_FLAG_BRIDGED_PKT;
+
+	src_node = mwifiex_get_sta_entry(priv, rx_pkt_hdr->eth803_hdr.h_source);
+	if (src_node) {
+		src_node->stats.last_rx = jiffies;
+		src_node->stats.rx_bytes += skb->len;
+		src_node->stats.rx_packets++;
+		src_node->stats.last_tx_rate = uap_rx_pd->rx_rate;
+		src_node->stats.last_tx_htinfo = uap_rx_pd->ht_info;
+	}
+
+	if (is_unicast_ether_addr(rx_pkt_hdr->eth803_hdr.h_dest)) {
+		/* Update bridge packet statistics as the
+		 * packet is not going to kernel/upper layer.
+		 */
+		priv->stats.rx_bytes += skb->len;
+		priv->stats.rx_packets++;
+
+		/* Sending bridge packet to TX queue, so save the packet
+		 * length in TXCB to update statistics in TX complete.
+		 */
+		tx_info->pkt_len = skb->len;
+	}
+
+	__net_timestamp(skb);
+	mwifiex_wmm_add_buf_txqueue(priv, skb);
+	atomic_inc(&adapter->tx_pending);
+	atomic_inc(&adapter->pending_bridged_pkts);
+
+	return;
+}
+
+/*
+ * This function contains logic for AP packet forwarding.
+ *
+ * If a packet is multicast/broadcast, it is sent to kernel/upper layer
+ * as well as queued back to AP TX queue so that it can be sent to other
+ * associated stations.
+ * If a packet is unicast and RA is present in associated station list,
+ * it is again requeued into AP TX queue.
+ * If a packet is unicast and RA is not in associated station list,
+ * packet is forwarded to kernel to handle routing logic.
+ */
+int mwifiex_handle_uap_rx_forward(struct mwifiex_private *priv,
+				  struct sk_buff *skb)
+{
+	struct mwifiex_adapter *adapter = priv->adapter;
+	struct uap_rxpd *uap_rx_pd;
+	struct rx_packet_hdr *rx_pkt_hdr;
+	u8 ra[ETH_ALEN];
+	struct sk_buff *skb_uap;
+
+	uap_rx_pd = (struct uap_rxpd *)(skb->data);
+	rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
+
+	/* don't do packet forwarding in disconnected state */
+	if (!priv->media_connected) {
+		mwifiex_dbg(adapter, ERROR,
+			    "drop packet in disconnected state.\n");
+		dev_kfree_skb_any(skb);
+		return 0;
+	}
+
+	memcpy(ra, rx_pkt_hdr->eth803_hdr.h_dest, ETH_ALEN);
+
+	if (is_multicast_ether_addr(ra)) {
+		skb_uap = skb_copy(skb, GFP_ATOMIC);
+		mwifiex_uap_queue_bridged_pkt(priv, skb_uap);
+	} else {
+		if (mwifiex_get_sta_entry(priv, ra)) {
+			/* Requeue Intra-BSS packet */
+			mwifiex_uap_queue_bridged_pkt(priv, skb);
+			return 0;
+		}
+	}
+
+	/* Forward unicat/Inter-BSS packets to kernel. */
+	return mwifiex_process_rx_packet(priv, skb);
+}
+
+/*
+ * This function processes the packet received on AP interface.
+ *
+ * The function looks into the RxPD and performs sanity tests on the
+ * received buffer to ensure its a valid packet before processing it
+ * further. If the packet is determined to be aggregated, it is
+ * de-aggregated accordingly. Then skb is passed to AP packet forwarding logic.
+ *
+ * The completion callback is called after processing is complete.
+ */
+int mwifiex_process_uap_rx_packet(struct mwifiex_private *priv,
+				  struct sk_buff *skb)
+{
+	struct mwifiex_adapter *adapter = priv->adapter;
+	int ret;
+	struct uap_rxpd *uap_rx_pd;
+	struct rx_packet_hdr *rx_pkt_hdr;
+	u16 rx_pkt_type;
+	u8 ta[ETH_ALEN], pkt_type;
+	unsigned long flags;
+	struct mwifiex_sta_node *node;
+
+	uap_rx_pd = (struct uap_rxpd *)(skb->data);
+	rx_pkt_type = le16_to_cpu(uap_rx_pd->rx_pkt_type);
+	rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
+
+	ether_addr_copy(ta, rx_pkt_hdr->eth803_hdr.h_source);
+
+	if ((le16_to_cpu(uap_rx_pd->rx_pkt_offset) +
+	     le16_to_cpu(uap_rx_pd->rx_pkt_length)) > (u16) skb->len) {
+		mwifiex_dbg(adapter, ERROR,
+			    "wrong rx packet: len=%d, offset=%d, length=%d\n",
+			    skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset),
+			    le16_to_cpu(uap_rx_pd->rx_pkt_length));
+		priv->stats.rx_dropped++;
+
+		node = mwifiex_get_sta_entry(priv, ta);
+		if (node)
+			node->stats.tx_failed++;
+
+		dev_kfree_skb_any(skb);
+		return 0;
+	}
+
+	if (rx_pkt_type == PKT_TYPE_MGMT) {
+		ret = mwifiex_process_mgmt_packet(priv, skb);
+		if (ret)
+			mwifiex_dbg(adapter, ERROR,
+				    "Rx of mgmt packet failed");
+		dev_kfree_skb_any(skb);
+		return ret;
+	}
+
+
+	if (rx_pkt_type != PKT_TYPE_BAR && uap_rx_pd->priority < MAX_NUM_TID) {
+		spin_lock_irqsave(&priv->sta_list_spinlock, flags);
+		node = mwifiex_get_sta_entry(priv, ta);
+		if (node)
+			node->rx_seq[uap_rx_pd->priority] =
+						le16_to_cpu(uap_rx_pd->seq_num);
+		spin_unlock_irqrestore(&priv->sta_list_spinlock, flags);
+	}
+
+	if (!priv->ap_11n_enabled ||
+	    (!mwifiex_11n_get_rx_reorder_tbl(priv, uap_rx_pd->priority, ta) &&
+	    (le16_to_cpu(uap_rx_pd->rx_pkt_type) != PKT_TYPE_AMSDU))) {
+		ret = mwifiex_handle_uap_rx_forward(priv, skb);
+		return ret;
+	}
+
+	/* Reorder and send to kernel */
+	pkt_type = (u8)le16_to_cpu(uap_rx_pd->rx_pkt_type);
+	ret = mwifiex_11n_rx_reorder_pkt(priv, le16_to_cpu(uap_rx_pd->seq_num),
+					 uap_rx_pd->priority, ta, pkt_type,
+					 skb);
+
+	if (ret || (rx_pkt_type == PKT_TYPE_BAR))
+		dev_kfree_skb_any(skb);
+
+	if (ret)
+		priv->stats.rx_dropped++;
+
+	return ret;
+}
+
+/*
+ * This function fills the TxPD for AP tx packets.
+ *
+ * The Tx buffer received by this function should already have the
+ * header space allocated for TxPD.
+ *
+ * This function inserts the TxPD in between interface header and actual
+ * data and adjusts the buffer pointers accordingly.
+ *
+ * The following TxPD fields are set by this function, as required -
+ *      - BSS number
+ *      - Tx packet length and offset
+ *      - Priority
+ *      - Packet delay
+ *      - Priority specific Tx control
+ *      - Flags
+ */
+void *mwifiex_process_uap_txpd(struct mwifiex_private *priv,
+			       struct sk_buff *skb)
+{
+	struct mwifiex_adapter *adapter = priv->adapter;
+	struct uap_txpd *txpd;
+	struct mwifiex_txinfo *tx_info = MWIFIEX_SKB_TXCB(skb);
+	int pad;
+	u16 pkt_type, pkt_offset;
+	int hroom = (priv->adapter->iface_type == MWIFIEX_USB) ? 0 :
+		       INTF_HEADER_LEN;
+
+	if (!skb->len) {
+		mwifiex_dbg(adapter, ERROR,
+			    "Tx: bad packet length: %d\n", skb->len);
+		tx_info->status_code = -1;
+		return skb->data;
+	}
+
+	BUG_ON(skb_headroom(skb) < MWIFIEX_MIN_DATA_HEADER_LEN);
+
+	pkt_type = mwifiex_is_skb_mgmt_frame(skb) ? PKT_TYPE_MGMT : 0;
+
+	pad = ((void *)skb->data - (sizeof(*txpd) + hroom) - NULL) &
+			(MWIFIEX_DMA_ALIGN_SZ - 1);
+
+	skb_push(skb, sizeof(*txpd) + pad);
+
+	txpd = (struct uap_txpd *)skb->data;
+	memset(txpd, 0, sizeof(*txpd));
+	txpd->bss_num = priv->bss_num;
+	txpd->bss_type = priv->bss_type;
+	txpd->tx_pkt_length = cpu_to_le16((u16)(skb->len - (sizeof(*txpd) +
+						pad)));
+	txpd->priority = (u8)skb->priority;
+
+	txpd->pkt_delay_2ms = mwifiex_wmm_compute_drv_pkt_delay(priv, skb);
+
+	if (tx_info->flags & MWIFIEX_BUF_FLAG_EAPOL_TX_STATUS ||
+	    tx_info->flags & MWIFIEX_BUF_FLAG_ACTION_TX_STATUS) {
+		txpd->tx_token_id = tx_info->ack_frame_id;
+		txpd->flags |= MWIFIEX_TXPD_FLAGS_REQ_TX_STATUS;
+	}
+
+	if (txpd->priority < ARRAY_SIZE(priv->wmm.user_pri_pkt_tx_ctrl))
+		/*
+		 * Set the priority specific tx_control field, setting of 0 will
+		 * cause the default value to be used later in this function.
+		 */
+		txpd->tx_control =
+		    cpu_to_le32(priv->wmm.user_pri_pkt_tx_ctrl[txpd->priority]);
+
+	/* Offset of actual data */
+	pkt_offset = sizeof(*txpd) + pad;
+	if (pkt_type == PKT_TYPE_MGMT) {
+		/* Set the packet type and add header for management frame */
+		txpd->tx_pkt_type = cpu_to_le16(pkt_type);
+		pkt_offset += MWIFIEX_MGMT_FRAME_HEADER_SIZE;
+	}
+
+	txpd->tx_pkt_offset = cpu_to_le16(pkt_offset);
+
+	/* make space for INTF_HEADER_LEN */
+	skb_push(skb, hroom);
+
+	if (!txpd->tx_control)
+		/* TxCtrl set by user or default */
+		txpd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);
+
+	return skb->data;
+}