[deliverable/linux.git] / drivers / net / wireless / mwifiex / 11n_rxreorder.c

/*
 * Marvell Wireless LAN device driver: 802.11n RX Re-ordering
 *
 * Copyright (C) 2011, 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 "util.h"
#include "fw.h"
#include "main.h"
#include "wmm.h"
#include "11n.h"
#include "11n_rxreorder.h"

/*
 * This function dispatches all packets in the Rx reorder table until the
 * start window.
 *
 * There could be holes in the buffer, which are skipped by the function.
 * Since the buffer is linear, the function uses rotation to simulate
 * circular buffer.
 */
static void
mwifiex_11n_dispatch_pkt(struct mwifiex_private *priv,
                         struct mwifiex_rx_reorder_tbl *tbl, int start_win)
{
        int pkt_to_send, i;
        void *rx_tmp_ptr;
        unsigned long flags;

        pkt_to_send = (start_win > tbl->start_win) ?
                      min((start_win - tbl->start_win), tbl->win_size) :
                      tbl->win_size;

        for (i = 0; i < pkt_to_send; ++i) {
                spin_lock_irqsave(&priv->rx_pkt_lock, flags);
                rx_tmp_ptr = NULL;
                if (tbl->rx_reorder_ptr[i]) {
                        rx_tmp_ptr = tbl->rx_reorder_ptr[i];
                        tbl->rx_reorder_ptr[i] = NULL;
                }
                spin_unlock_irqrestore(&priv->rx_pkt_lock, flags);
                if (rx_tmp_ptr) {
                        if (priv->bss_role == MWIFIEX_BSS_ROLE_UAP)
                                mwifiex_handle_uap_rx_forward(priv, rx_tmp_ptr);
                        else
                                mwifiex_process_rx_packet(priv->adapter,
                                                          rx_tmp_ptr);
                }
        }

        spin_lock_irqsave(&priv->rx_pkt_lock, flags);
        /*
         * We don't have a circular buffer, hence use rotation to simulate
         * circular buffer
         */
        for (i = 0; i < tbl->win_size - pkt_to_send; ++i) {
                tbl->rx_reorder_ptr[i] = tbl->rx_reorder_ptr[pkt_to_send + i];
                tbl->rx_reorder_ptr[pkt_to_send + i] = NULL;
        }

        tbl->start_win = start_win;
        spin_unlock_irqrestore(&priv->rx_pkt_lock, flags);
}

/*
 * This function dispatches all packets in the Rx reorder table until
 * a hole is found.
 *
 * The start window is adjusted automatically when a hole is located.
 * Since the buffer is linear, the function uses rotation to simulate
 * circular buffer.
 */
static void
mwifiex_11n_scan_and_dispatch(struct mwifiex_private *priv,
                              struct mwifiex_rx_reorder_tbl *tbl)
{
        int i, j, xchg;
        void *rx_tmp_ptr;
        unsigned long flags;

        for (i = 0; i < tbl->win_size; ++i) {
                spin_lock_irqsave(&priv->rx_pkt_lock, flags);
                if (!tbl->rx_reorder_ptr[i]) {
                        spin_unlock_irqrestore(&priv->rx_pkt_lock, flags);
                        break;
                }
                rx_tmp_ptr = tbl->rx_reorder_ptr[i];
                tbl->rx_reorder_ptr[i] = NULL;
                spin_unlock_irqrestore(&priv->rx_pkt_lock, flags);

                if (priv->bss_role == MWIFIEX_BSS_ROLE_UAP)
                        mwifiex_handle_uap_rx_forward(priv, rx_tmp_ptr);
                else
                        mwifiex_process_rx_packet(priv->adapter, rx_tmp_ptr);
        }

        spin_lock_irqsave(&priv->rx_pkt_lock, flags);
        /*
         * We don't have a circular buffer, hence use rotation to simulate
         * circular buffer
         */
        if (i > 0) {
                xchg = tbl->win_size - i;
                for (j = 0; j < xchg; ++j) {
                        tbl->rx_reorder_ptr[j] = tbl->rx_reorder_ptr[i + j];
                        tbl->rx_reorder_ptr[i + j] = NULL;
                }
        }
        tbl->start_win = (tbl->start_win + i) & (MAX_TID_VALUE - 1);
        spin_unlock_irqrestore(&priv->rx_pkt_lock, flags);
}

/*
 * This function deletes the Rx reorder table and frees the memory.
 *
 * The function stops the associated timer and dispatches all the
 * pending packets in the Rx reorder table before deletion.
 */
static void
mwifiex_del_rx_reorder_entry(struct mwifiex_private *priv,
                             struct mwifiex_rx_reorder_tbl *tbl)
{
        unsigned long flags;

        if (!tbl)
                return;

        mwifiex_11n_dispatch_pkt(priv, tbl, (tbl->start_win + tbl->win_size) &
                                            (MAX_TID_VALUE - 1));

        del_timer(&tbl->timer_context.timer);

        spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
        list_del(&tbl->list);
        spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);

        kfree(tbl->rx_reorder_ptr);
        kfree(tbl);
}

/*
 * This function returns the pointer to an entry in Rx reordering
 * table which matches the given TA/TID pair.
 */
struct mwifiex_rx_reorder_tbl *
mwifiex_11n_get_rx_reorder_tbl(struct mwifiex_private *priv, int tid, u8 *ta)
{
        struct mwifiex_rx_reorder_tbl *tbl;
        unsigned long flags;

        spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
        list_for_each_entry(tbl, &priv->rx_reorder_tbl_ptr, list) {
                if (!memcmp(tbl->ta, ta, ETH_ALEN) && tbl->tid == tid) {
                        spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock,
                                               flags);
                        return tbl;
                }
        }
        spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);

        return NULL;
}

/*
 * This function finds the last sequence number used in the packets
 * buffered in Rx reordering table.
 */
static int
mwifiex_11n_find_last_seq_num(struct mwifiex_rx_reorder_tbl *rx_reorder_tbl_ptr)
{
        int i;

        for (i = (rx_reorder_tbl_ptr->win_size - 1); i >= 0; --i)
                if (rx_reorder_tbl_ptr->rx_reorder_ptr[i])
                        return i;

        return -1;
}

/*
 * This function flushes all the packets in Rx reordering table.
 *
 * The function checks if any packets are currently buffered in the
 * table or not. In case there are packets available, it dispatches
 * them and then dumps the Rx reordering table.
 */
static void
mwifiex_flush_data(unsigned long context)
{
        struct reorder_tmr_cnxt *ctx =
                (struct reorder_tmr_cnxt *) context;
        int start_win;

        start_win = mwifiex_11n_find_last_seq_num(ctx->ptr);

        if (start_win < 0)
                return;

        dev_dbg(ctx->priv->adapter->dev, "info: flush data %d\n", start_win);
        mwifiex_11n_dispatch_pkt(ctx->priv, ctx->ptr,
                                 (ctx->ptr->start_win + start_win + 1) &
                                 (MAX_TID_VALUE - 1));
}

/*
 * This function creates an entry in Rx reordering table for the
 * given TA/TID.
 *
 * The function also initializes the entry with sequence number, window
 * size as well as initializes the timer.
 *
 * If the received TA/TID pair is already present, all the packets are
 * dispatched and the window size is moved until the SSN.
 */
static void
mwifiex_11n_create_rx_reorder_tbl(struct mwifiex_private *priv, u8 *ta,
                                  int tid, int win_size, int seq_num)
{
        int i;
        struct mwifiex_rx_reorder_tbl *tbl, *new_node;
        u16 last_seq = 0;
        unsigned long flags;

        /*
         * If we get a TID, ta pair which is already present dispatch all the
         * the packets and move the window size until the ssn
         */
        tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, ta);
        if (tbl) {
                mwifiex_11n_dispatch_pkt(priv, tbl, seq_num);
                return;
        }
        /* if !tbl then create one */
        new_node = kzalloc(sizeof(struct mwifiex_rx_reorder_tbl), GFP_KERNEL);
        if (!new_node) {
                dev_err(priv->adapter->dev, "%s: failed to alloc new_node\n",
                        __func__);
                return;
        }

        INIT_LIST_HEAD(&new_node->list);
        new_node->tid = tid;
        memcpy(new_node->ta, ta, ETH_ALEN);
        new_node->start_win = seq_num;
        if (mwifiex_queuing_ra_based(priv))
                /* TODO for adhoc */
                dev_dbg(priv->adapter->dev,
                        "info: ADHOC:last_seq=%d start_win=%d\n",
                        last_seq, new_node->start_win);
        else
                last_seq = priv->rx_seq[tid];

        if (last_seq != MWIFIEX_DEF_11N_RX_SEQ_NUM &&
            last_seq >= new_node->start_win)
                new_node->start_win = last_seq + 1;

        new_node->win_size = win_size;

        new_node->rx_reorder_ptr = kzalloc(sizeof(void *) * win_size,
                                        GFP_KERNEL);
        if (!new_node->rx_reorder_ptr) {
                kfree((u8 *) new_node);
                dev_err(priv->adapter->dev,
                        "%s: failed to alloc reorder_ptr\n", __func__);
                return;
        }

        new_node->timer_context.ptr = new_node;
        new_node->timer_context.priv = priv;

        init_timer(&new_node->timer_context.timer);
        new_node->timer_context.timer.function = mwifiex_flush_data;
        new_node->timer_context.timer.data =
                        (unsigned long) &new_node->timer_context;

        for (i = 0; i < win_size; ++i)
                new_node->rx_reorder_ptr[i] = NULL;

        spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
        list_add_tail(&new_node->list, &priv->rx_reorder_tbl_ptr);
        spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
}

/*
 * This function prepares command for adding a BA request.
 *
 * Preparation includes -
 *      - Setting command ID and proper size
 *      - Setting add BA request buffer
 *      - Ensuring correct endian-ness
 */
int mwifiex_cmd_11n_addba_req(struct host_cmd_ds_command *cmd, void *data_buf)
{
        struct host_cmd_ds_11n_addba_req *add_ba_req = &cmd->params.add_ba_req;

        cmd->command = cpu_to_le16(HostCmd_CMD_11N_ADDBA_REQ);
        cmd->size = cpu_to_le16(sizeof(*add_ba_req) + S_DS_GEN);
        memcpy(add_ba_req, data_buf, sizeof(*add_ba_req));

        return 0;
}

/*
 * This function prepares command for adding a BA response.
 *
 * Preparation includes -
 *      - Setting command ID and proper size
 *      - Setting add BA response buffer
 *      - Ensuring correct endian-ness
 */
int mwifiex_cmd_11n_addba_rsp_gen(struct mwifiex_private *priv,
                                  struct host_cmd_ds_command *cmd,
                                  struct host_cmd_ds_11n_addba_req
                                  *cmd_addba_req)
{
        struct host_cmd_ds_11n_addba_rsp *add_ba_rsp = &cmd->params.add_ba_rsp;
        u8 tid;
        int win_size;
        uint16_t block_ack_param_set;

        cmd->command = cpu_to_le16(HostCmd_CMD_11N_ADDBA_RSP);
        cmd->size = cpu_to_le16(sizeof(*add_ba_rsp) + S_DS_GEN);

        memcpy(add_ba_rsp->peer_mac_addr, cmd_addba_req->peer_mac_addr,
               ETH_ALEN);
        add_ba_rsp->dialog_token = cmd_addba_req->dialog_token;
        add_ba_rsp->block_ack_tmo = cmd_addba_req->block_ack_tmo;
        add_ba_rsp->ssn = cmd_addba_req->ssn;

        block_ack_param_set = le16_to_cpu(cmd_addba_req->block_ack_param_set);
        tid = (block_ack_param_set & IEEE80211_ADDBA_PARAM_TID_MASK)
                >> BLOCKACKPARAM_TID_POS;
        add_ba_rsp->status_code = cpu_to_le16(ADDBA_RSP_STATUS_ACCEPT);
        block_ack_param_set &= ~IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK;
        /* We donot support AMSDU inside AMPDU, hence reset the bit */
        block_ack_param_set &= ~BLOCKACKPARAM_AMSDU_SUPP_MASK;
        block_ack_param_set |= (priv->add_ba_param.rx_win_size <<
                                             BLOCKACKPARAM_WINSIZE_POS);
        add_ba_rsp->block_ack_param_set = cpu_to_le16(block_ack_param_set);
        win_size = (le16_to_cpu(add_ba_rsp->block_ack_param_set)
                                        & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK)
                                        >> BLOCKACKPARAM_WINSIZE_POS;
        cmd_addba_req->block_ack_param_set = cpu_to_le16(block_ack_param_set);

        mwifiex_11n_create_rx_reorder_tbl(priv, cmd_addba_req->peer_mac_addr,
                                          tid, win_size,
                                          le16_to_cpu(cmd_addba_req->ssn));
        return 0;
}

/*
 * This function prepares command for deleting a BA request.
 *
 * Preparation includes -
 *      - Setting command ID and proper size
 *      - Setting del BA request buffer
 *      - Ensuring correct endian-ness
 */
int mwifiex_cmd_11n_delba(struct host_cmd_ds_command *cmd, void *data_buf)
{
        struct host_cmd_ds_11n_delba *del_ba = &cmd->params.del_ba;

        cmd->command = cpu_to_le16(HostCmd_CMD_11N_DELBA);
        cmd->size = cpu_to_le16(sizeof(*del_ba) + S_DS_GEN);
        memcpy(del_ba, data_buf, sizeof(*del_ba));

        return 0;
}

/*
 * This function identifies if Rx reordering is needed for a received packet.
 *
 * In case reordering is required, the function will do the reordering
 * before sending it to kernel.
 *
 * The Rx reorder table is checked first with the received TID/TA pair. If
 * not found, the received packet is dispatched immediately. But if found,
 * the packet is reordered and all the packets in the updated Rx reordering
 * table is dispatched until a hole is found.
 *
 * For sequence number less than the starting window, the packet is dropped.
 */
int mwifiex_11n_rx_reorder_pkt(struct mwifiex_private *priv,
                                u16 seq_num, u16 tid,
                                u8 *ta, u8 pkt_type, void *payload)
{
        struct mwifiex_rx_reorder_tbl *tbl;
        int start_win, end_win, win_size;
        u16 pkt_index;

        tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid, ta);
        if (!tbl) {
                if (pkt_type != PKT_TYPE_BAR) {
                        if (priv->bss_role == MWIFIEX_BSS_ROLE_UAP)
                                mwifiex_handle_uap_rx_forward(priv, payload);
                        else
                                mwifiex_process_rx_packet(priv->adapter,
                                                          payload);
                }
                return 0;
        }
        start_win = tbl->start_win;
        win_size = tbl->win_size;
        end_win = ((start_win + win_size) - 1) & (MAX_TID_VALUE - 1);
        del_timer(&tbl->timer_context.timer);
        mod_timer(&tbl->timer_context.timer,
                  jiffies + (MIN_FLUSH_TIMER_MS * win_size * HZ) / 1000);

        /*
         * If seq_num is less then starting win then ignore and drop the
         * packet
         */
        if ((start_win + TWOPOW11) > (MAX_TID_VALUE - 1)) {/* Wrap */
                if (seq_num >= ((start_win + TWOPOW11) &
                                (MAX_TID_VALUE - 1)) && (seq_num < start_win))
                        return -1;
        } else if ((seq_num < start_win) ||
                   (seq_num > (start_win + TWOPOW11))) {
                return -1;
        }

        /*
         * If this packet is a BAR we adjust seq_num as
         * WinStart = seq_num
         */
        if (pkt_type == PKT_TYPE_BAR)
                seq_num = ((seq_num + win_size) - 1) & (MAX_TID_VALUE - 1);

        if (((end_win < start_win) &&
             (seq_num < (TWOPOW11 - (MAX_TID_VALUE - start_win))) &&
             (seq_num > end_win)) ||
            ((end_win > start_win) && ((seq_num > end_win) ||
                                       (seq_num < start_win)))) {
                end_win = seq_num;
                if (((seq_num - win_size) + 1) >= 0)
                        start_win = (end_win - win_size) + 1;
                else
                        start_win = (MAX_TID_VALUE - (win_size - seq_num)) + 1;
                mwifiex_11n_dispatch_pkt(priv, tbl, start_win);
        }

        if (pkt_type != PKT_TYPE_BAR) {
                if (seq_num >= start_win)
                        pkt_index = seq_num - start_win;
                else
                        pkt_index = (seq_num+MAX_TID_VALUE) - start_win;

                if (tbl->rx_reorder_ptr[pkt_index])
                        return -1;

                tbl->rx_reorder_ptr[pkt_index] = payload;
        }

        /*
         * Dispatch all packets sequentially from start_win until a
         * hole is found and adjust the start_win appropriately
         */
        mwifiex_11n_scan_and_dispatch(priv, tbl);

        return 0;
}

/*
 * This function deletes an entry for a given TID/TA pair.
 *
 * The TID/TA are taken from del BA event body.
 */
void
mwifiex_del_ba_tbl(struct mwifiex_private *priv, int tid, u8 *peer_mac,
                   u8 type, int initiator)
{
        struct mwifiex_rx_reorder_tbl *tbl;
        struct mwifiex_tx_ba_stream_tbl *ptx_tbl;
        u8 cleanup_rx_reorder_tbl;
        unsigned long flags;

        if (type == TYPE_DELBA_RECEIVE)
                cleanup_rx_reorder_tbl = (initiator) ? true : false;
        else
                cleanup_rx_reorder_tbl = (initiator) ? false : true;

        dev_dbg(priv->adapter->dev, "event: DELBA: %pM tid=%d initiator=%d\n",
                peer_mac, tid, initiator);

        if (cleanup_rx_reorder_tbl) {
                tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid,
                                                                 peer_mac);
                if (!tbl) {
                        dev_dbg(priv->adapter->dev,
                                "event: TID, TA not found in table\n");
                        return;
                }
                mwifiex_del_rx_reorder_entry(priv, tbl);
        } else {
                ptx_tbl = mwifiex_get_ba_tbl(priv, tid, peer_mac);
                if (!ptx_tbl) {
                        dev_dbg(priv->adapter->dev,
                                "event: TID, RA not found in table\n");
                        return;
                }

                spin_lock_irqsave(&priv->tx_ba_stream_tbl_lock, flags);
                mwifiex_11n_delete_tx_ba_stream_tbl_entry(priv, ptx_tbl);
                spin_unlock_irqrestore(&priv->tx_ba_stream_tbl_lock, flags);
        }
}

/*
 * This function handles the command response of an add BA response.
 *
 * Handling includes changing the header fields into CPU format and
 * creating the stream, provided the add BA is accepted.
 */
int mwifiex_ret_11n_addba_resp(struct mwifiex_private *priv,
                               struct host_cmd_ds_command *resp)
{
        struct host_cmd_ds_11n_addba_rsp *add_ba_rsp = &resp->params.add_ba_rsp;
        int tid, win_size;
        struct mwifiex_rx_reorder_tbl *tbl;
        uint16_t block_ack_param_set;

        block_ack_param_set = le16_to_cpu(add_ba_rsp->block_ack_param_set);

        tid = (block_ack_param_set & IEEE80211_ADDBA_PARAM_TID_MASK)
                >> BLOCKACKPARAM_TID_POS;
        /*
         * Check if we had rejected the ADDBA, if yes then do not create
         * the stream
         */
        if (le16_to_cpu(add_ba_rsp->status_code) == BA_RESULT_SUCCESS) {
                win_size = (block_ack_param_set &
                        IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK)
                        >> BLOCKACKPARAM_WINSIZE_POS;

                dev_dbg(priv->adapter->dev,
                        "cmd: ADDBA RSP: %pM tid=%d ssn=%d win_size=%d\n",
                        add_ba_rsp->peer_mac_addr, tid,
                        add_ba_rsp->ssn, win_size);
        } else {
                dev_err(priv->adapter->dev, "ADDBA RSP: failed %pM tid=%d)\n",
                        add_ba_rsp->peer_mac_addr, tid);

                tbl = mwifiex_11n_get_rx_reorder_tbl(priv, tid,
                                                     add_ba_rsp->peer_mac_addr);
                if (tbl)
                        mwifiex_del_rx_reorder_entry(priv, tbl);
        }

        return 0;
}

/*
 * This function handles BA stream timeout event by preparing and sending
 * a command to the firmware.
 */
void mwifiex_11n_ba_stream_timeout(struct mwifiex_private *priv,
                                   struct host_cmd_ds_11n_batimeout *event)
{
        struct host_cmd_ds_11n_delba delba;

        memset(&delba, 0, sizeof(struct host_cmd_ds_11n_delba));
        memcpy(delba.peer_mac_addr, event->peer_mac_addr, ETH_ALEN);

        delba.del_ba_param_set |=
                cpu_to_le16((u16) event->tid << DELBA_TID_POS);
        delba.del_ba_param_set |= cpu_to_le16(
                (u16) event->origninator << DELBA_INITIATOR_POS);
        delba.reason_code = cpu_to_le16(WLAN_REASON_QSTA_TIMEOUT);
        mwifiex_send_cmd_async(priv, HostCmd_CMD_11N_DELBA, 0, 0, &delba);
}

/*
 * This function cleans up the Rx reorder table by deleting all the entries
 * and re-initializing.
 */
void mwifiex_11n_cleanup_reorder_tbl(struct mwifiex_private *priv)
{
        struct mwifiex_rx_reorder_tbl *del_tbl_ptr, *tmp_node;
        unsigned long flags;

        spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
        list_for_each_entry_safe(del_tbl_ptr, tmp_node,
                                 &priv->rx_reorder_tbl_ptr, list) {
                spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);
                mwifiex_del_rx_reorder_entry(priv, del_tbl_ptr);
                spin_lock_irqsave(&priv->rx_reorder_tbl_lock, flags);
        }
        spin_unlock_irqrestore(&priv->rx_reorder_tbl_lock, flags);

        INIT_LIST_HEAD(&priv->rx_reorder_tbl_ptr);
        mwifiex_reset_11n_rx_seq_num(priv);
}