core/dp/txrx/ol_rx_fwd.c

/*
 * Copyright (c) 2011, 2014-2016 The Linux Foundation. All rights reserved.
 *
 * Previously licensed under the ISC license by Qualcomm Atheros, Inc.
 *
 *
 * Permission to use, copy, modify, and/or distribute this software for
 * any purpose with or without fee is hereby granted, provided that the
 * above copyright notice and this permission notice appear in all
 * copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
 * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * This file was originally distributed by Qualcomm Atheros, Inc.
 * under proprietary terms before Copyright ownership was assigned
 * to the Linux Foundation.
 */

/* standard header files */
#include <qdf_nbuf.h>           /* qdf_nbuf_map */
#include <qdf_mem.h>         /* qdf_mem_cmp */

/* external header files */
#include <ol_cfg.h>                 /* wlan_op_mode_ap, etc. */
#include <ol_htt_rx_api.h>          /* htt_rx_msdu_desc_retrieve */
#include <cds_ieee80211_common.h>   /* ieee80211_frame, etc. */

/* internal header files */
#include <ol_txrx_types.h>      /* ol_txrx_dev_t, etc. */
#include <ol_rx_fwd.h>          /* our own defs */
#include <ol_rx.h>              /* ol_rx_deliver */
#include <ol_txrx_internal.h>   /* TXRX_ASSERT1 */
#include <ol_tx.h>
/*
 * Porting from Ap11PrepareForwardedPacket.
 * This routine is called when a RX data frame from an associated station is
 * to be forwarded to another associated station. We will prepare the
 * received packet so that it is suitable for transmission again.
 * Check that this Packet is suitable for forwarding. If yes, then
 * prepare the new 802.11 header.
 */
static inline void ol_ap_fwd_check(struct ol_txrx_vdev_t *vdev, qdf_nbuf_t msdu)
{
	struct ieee80211_frame *mac_header;
	unsigned char tmp_addr[IEEE80211_ADDR_LEN];
	unsigned char type;
	unsigned char subtype;
	unsigned char fromds;
	unsigned char tods;

	mac_header = (struct ieee80211_frame *)(qdf_nbuf_data(msdu));
	TXRX_ASSERT1(mac_header);

	type = mac_header->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
	subtype = mac_header->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
	tods = mac_header->i_fc[1] & IEEE80211_FC1_DIR_TODS;
	fromds = mac_header->i_fc[1] & IEEE80211_FC1_DIR_FROMDS;

	/*
	 * Make sure no QOS or any other non-data subtype
	 * Should be a ToDs data frame.
	 * Make sure that this frame is unicast and not for us.
	 * These packets should come up through the normal rx path and
	 * not forwarded.
	 */
	if (type != IEEE80211_FC0_TYPE_DATA ||
	    subtype != 0x0 ||
	    ((tods != 1) || (fromds != 0)) ||
	    (qdf_mem_cmp
		     (mac_header->i_addr3, vdev->mac_addr.raw,
		     IEEE80211_ADDR_LEN) != 0)) {
#ifdef DEBUG_HOST_RC
		TXRX_PRINT(TXRX_PRINT_LEVEL_INFO1,
			   "Exit: %s | Unnecessary to adjust mac header\n",
			   __func__);
#endif
	} else {
		/* Flip the ToDs bit to FromDs */
		mac_header->i_fc[1] &= 0xfe;
		mac_header->i_fc[1] |= 0x2;

		/*
		 * Flip the addresses
		 * (ToDs, addr1, RA=BSSID) move to (FrDs, addr2, TA=BSSID)
		 * (ToDs, addr2, SA) move to (FrDs, addr3, SA)
		 * (ToDs, addr3, DA) move to (FrDs, addr1, DA)
		 */

		memcpy(tmp_addr, mac_header->i_addr2, sizeof(tmp_addr));

		memcpy(mac_header->i_addr2,
		       mac_header->i_addr1, sizeof(tmp_addr));

		memcpy(mac_header->i_addr1,
		       mac_header->i_addr3, sizeof(tmp_addr));

		memcpy(mac_header->i_addr3, tmp_addr, sizeof(tmp_addr));
	}
}

static inline void ol_rx_fwd_to_tx(struct ol_txrx_vdev_t *vdev, qdf_nbuf_t msdu)
{
	struct ol_txrx_pdev_t *pdev = vdev->pdev;

	if (pdev->frame_format == wlan_frm_fmt_native_wifi)
		ol_ap_fwd_check(vdev, msdu);

	/*
	 * Map the netbuf, so it's accessible to the DMA that
	 * sends it to the target.
	 */
	qdf_nbuf_map_single(pdev->osdev, msdu, QDF_DMA_TO_DEVICE);
	qdf_nbuf_set_next(msdu, NULL);  /* add NULL terminator */

	msdu = OL_TX_LL(vdev, msdu);

	if (msdu) {
		/*
		 * The frame was not accepted by the tx.
		 * We could store the frame and try again later,
		 * but the simplest solution is to discard the frames.
		 */
		qdf_nbuf_unmap_single(pdev->osdev, msdu, QDF_DMA_TO_DEVICE);
		qdf_nbuf_tx_free(msdu, QDF_NBUF_PKT_ERROR);
	}
}

void
ol_rx_fwd_check(struct ol_txrx_vdev_t *vdev,
		struct ol_txrx_peer_t *peer, unsigned tid, qdf_nbuf_t msdu_list)
{
	struct ol_txrx_pdev_t *pdev = vdev->pdev;
	qdf_nbuf_t deliver_list_head = NULL;
	qdf_nbuf_t deliver_list_tail = NULL;
	qdf_nbuf_t msdu;

	msdu = msdu_list;
	while (msdu) {
		struct ol_txrx_vdev_t *tx_vdev;
		void *rx_desc;
		/*
		 * Remember the next list elem, because our processing
		 * may cause the MSDU to get linked into a different list.
		 */
		msdu_list = qdf_nbuf_next(msdu);

		rx_desc = htt_rx_msdu_desc_retrieve(pdev->htt_pdev, msdu);

		if (!vdev->disable_intrabss_fwd &&
		    htt_rx_msdu_forward(pdev->htt_pdev, rx_desc)) {
			/*
			 * Use the same vdev that received the frame to
			 * transmit the frame.
			 * This is exactly what we want for intra-BSS
			 * forwarding, like STA-to-STA forwarding and
			 * multicast echo.
			 * If this is a intra-BSS forwarding case (which is not
			 * currently supported), then the tx vdev is different
			 * from the rx vdev.
			 * On the LL host the vdevs are not actually used
			 * for tx, so it would still work to use the rx vdev
			 * rather than the tx vdev.
			 * For HL, the tx classification searches for the DA
			 * within the given vdev, so we would want to get the DA
			 * peer ID from the target, so we can locate
			 * the tx vdev.
			 */
			tx_vdev = vdev;
			/*
			 * Copying TID value of RX packet to forwarded
			 * packet if the tid is other than non qos tid.
			 * But for non qos tid fill invalid tid so that
			 * Fw will take care of filling proper tid.
			 */
			if (tid != HTT_NON_QOS_TID) {
				qdf_nbuf_set_tid(msdu, tid);
			} else {
				qdf_nbuf_set_tid(msdu,
						 QDF_NBUF_TX_EXT_TID_INVALID);
			}
			/*
			 * This MSDU needs to be forwarded to the tx path.
			 * Check whether it also needs to be sent to the OS
			 * shim, in which case we need to make a copy
			 * (or clone?).
			 */
			if (htt_rx_msdu_discard(pdev->htt_pdev, rx_desc)) {
				htt_rx_msdu_desc_free(pdev->htt_pdev, msdu);
				qdf_net_buf_debug_release_skb(msdu);
				ol_rx_fwd_to_tx(tx_vdev, msdu);
				msdu = NULL;    /* already handled this MSDU */
				TXRX_STATS_ADD(pdev,
					 pub.rx.intra_bss_fwd.packets_fwd, 1);
			} else {
				qdf_nbuf_t copy;
				copy = qdf_nbuf_copy(msdu);
				if (copy)
					ol_rx_fwd_to_tx(tx_vdev, copy);
				TXRX_STATS_ADD(pdev,
				   pub.rx.intra_bss_fwd.packets_stack_n_fwd, 1);
			}
		} else {
			TXRX_STATS_ADD(pdev,
				 pub.rx.intra_bss_fwd.packets_stack, 1);
		}
		if (msdu) {
			/* send this frame to the OS */
			OL_TXRX_LIST_APPEND(deliver_list_head,
					    deliver_list_tail, msdu);
		}
		msdu = msdu_list;
	}
	if (deliver_list_head) {
		/* add NULL terminator */
		qdf_nbuf_set_next(deliver_list_tail, NULL);
		if (ol_cfg_is_full_reorder_offload(pdev->ctrl_pdev)) {
			ol_rx_in_order_deliver(vdev, peer, tid,
					       deliver_list_head);
		} else {
			ol_rx_deliver(vdev, peer, tid, deliver_list_head);
		}
	}
}