/* * Marvell Wireless LAN device driver: utility functions * * Copyright (C) 2011-2014, 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 "util.h" #include "fw.h" #include "main.h" #include "wmm.h" #include "11n.h" static struct mwifiex_debug_data items[] = { {"debug_mask", item_size(debug_mask), item_addr(debug_mask), 1}, {"int_counter", item_size(int_counter), item_addr(int_counter), 1}, {"wmm_ac_vo", item_size(packets_out[WMM_AC_VO]), item_addr(packets_out[WMM_AC_VO]), 1}, {"wmm_ac_vi", item_size(packets_out[WMM_AC_VI]), item_addr(packets_out[WMM_AC_VI]), 1}, {"wmm_ac_be", item_size(packets_out[WMM_AC_BE]), item_addr(packets_out[WMM_AC_BE]), 1}, {"wmm_ac_bk", item_size(packets_out[WMM_AC_BK]), item_addr(packets_out[WMM_AC_BK]), 1}, {"tx_buf_size", item_size(tx_buf_size), item_addr(tx_buf_size), 1}, {"curr_tx_buf_size", item_size(curr_tx_buf_size), item_addr(curr_tx_buf_size), 1}, {"ps_mode", item_size(ps_mode), item_addr(ps_mode), 1}, {"ps_state", item_size(ps_state), item_addr(ps_state), 1}, {"is_deep_sleep", item_size(is_deep_sleep), item_addr(is_deep_sleep), 1}, {"wakeup_dev_req", item_size(pm_wakeup_card_req), item_addr(pm_wakeup_card_req), 1}, {"wakeup_tries", item_size(pm_wakeup_fw_try), item_addr(pm_wakeup_fw_try), 1}, {"hs_configured", item_size(is_hs_configured), item_addr(is_hs_configured), 1}, {"hs_activated", item_size(hs_activated), item_addr(hs_activated), 1}, {"num_tx_timeout", item_size(num_tx_timeout), item_addr(num_tx_timeout), 1}, {"is_cmd_timedout", item_size(is_cmd_timedout), item_addr(is_cmd_timedout), 1}, {"timeout_cmd_id", item_size(timeout_cmd_id), item_addr(timeout_cmd_id), 1}, {"timeout_cmd_act", item_size(timeout_cmd_act), item_addr(timeout_cmd_act), 1}, {"last_cmd_id", item_size(last_cmd_id), item_addr(last_cmd_id), DBG_CMD_NUM}, {"last_cmd_act", item_size(last_cmd_act), item_addr(last_cmd_act), DBG_CMD_NUM}, {"last_cmd_index", item_size(last_cmd_index), item_addr(last_cmd_index), 1}, {"last_cmd_resp_id", item_size(last_cmd_resp_id), item_addr(last_cmd_resp_id), DBG_CMD_NUM}, {"last_cmd_resp_index", item_size(last_cmd_resp_index), item_addr(last_cmd_resp_index), 1}, {"last_event", item_size(last_event), item_addr(last_event), DBG_CMD_NUM}, {"last_event_index", item_size(last_event_index), item_addr(last_event_index), 1}, {"num_cmd_h2c_fail", item_size(num_cmd_host_to_card_failure), item_addr(num_cmd_host_to_card_failure), 1}, {"num_cmd_sleep_cfm_fail", item_size(num_cmd_sleep_cfm_host_to_card_failure), item_addr(num_cmd_sleep_cfm_host_to_card_failure), 1}, {"num_tx_h2c_fail", item_size(num_tx_host_to_card_failure), item_addr(num_tx_host_to_card_failure), 1}, {"num_evt_deauth", item_size(num_event_deauth), item_addr(num_event_deauth), 1}, {"num_evt_disassoc", item_size(num_event_disassoc), item_addr(num_event_disassoc), 1}, {"num_evt_link_lost", item_size(num_event_link_lost), item_addr(num_event_link_lost), 1}, {"num_cmd_deauth", item_size(num_cmd_deauth), item_addr(num_cmd_deauth), 1}, {"num_cmd_assoc_ok", item_size(num_cmd_assoc_success), item_addr(num_cmd_assoc_success), 1}, {"num_cmd_assoc_fail", item_size(num_cmd_assoc_failure), item_addr(num_cmd_assoc_failure), 1}, {"cmd_sent", item_size(cmd_sent), item_addr(cmd_sent), 1}, {"data_sent", item_size(data_sent), item_addr(data_sent), 1}, {"cmd_resp_received", item_size(cmd_resp_received), item_addr(cmd_resp_received), 1}, {"event_received", item_size(event_received), item_addr(event_received), 1}, /* variables defined in struct mwifiex_adapter */ {"cmd_pending", adapter_item_size(cmd_pending), adapter_item_addr(cmd_pending), 1}, {"tx_pending", adapter_item_size(tx_pending), adapter_item_addr(tx_pending), 1}, {"rx_pending", adapter_item_size(rx_pending), adapter_item_addr(rx_pending), 1}, }; static int num_of_items = ARRAY_SIZE(items); /* * Firmware initialization complete callback handler. * * This function wakes up the function waiting on the init * wait queue for the firmware initialization to complete. */ int mwifiex_init_fw_complete(struct mwifiex_adapter *adapter) { adapter->init_wait_q_woken = true; wake_up_interruptible(&adapter->init_wait_q); return 0; } /* * Firmware shutdown complete callback handler. * * This function sets the hardware status to not ready and wakes up * the function waiting on the init wait queue for the firmware * shutdown to complete. */ int mwifiex_shutdown_fw_complete(struct mwifiex_adapter *adapter) { adapter->hw_status = MWIFIEX_HW_STATUS_NOT_READY; adapter->init_wait_q_woken = true; wake_up_interruptible(&adapter->init_wait_q); return 0; } /* * This function sends init/shutdown command * to firmware. */ int mwifiex_init_shutdown_fw(struct mwifiex_private *priv, u32 func_init_shutdown) { u16 cmd; if (func_init_shutdown == MWIFIEX_FUNC_INIT) { cmd = HostCmd_CMD_FUNC_INIT; } else if (func_init_shutdown == MWIFIEX_FUNC_SHUTDOWN) { cmd = HostCmd_CMD_FUNC_SHUTDOWN; } else { mwifiex_dbg(priv->adapter, ERROR, "unsupported parameter\n"); return -1; } return mwifiex_send_cmd(priv, cmd, HostCmd_ACT_GEN_SET, 0, NULL, true); } EXPORT_SYMBOL_GPL(mwifiex_init_shutdown_fw); /* * IOCTL request handler to set/get debug information. * * This function collates/sets the information from/to different driver * structures. */ int mwifiex_get_debug_info(struct mwifiex_private *priv, struct mwifiex_debug_info *info) { struct mwifiex_adapter *adapter = priv->adapter; if (info) { info->debug_mask = adapter->debug_mask; memcpy(info->packets_out, priv->wmm.packets_out, sizeof(priv->wmm.packets_out)); info->curr_tx_buf_size = (u32) adapter->curr_tx_buf_size; info->tx_buf_size = (u32) adapter->tx_buf_size; info->rx_tbl_num = mwifiex_get_rx_reorder_tbl(priv, info->rx_tbl); info->tx_tbl_num = mwifiex_get_tx_ba_stream_tbl(priv, info->tx_tbl); info->tdls_peer_num = mwifiex_get_tdls_list(priv, info->tdls_list); info->ps_mode = adapter->ps_mode; info->ps_state = adapter->ps_state; info->is_deep_sleep = adapter->is_deep_sleep; info->pm_wakeup_card_req = adapter->pm_wakeup_card_req; info->pm_wakeup_fw_try = adapter->pm_wakeup_fw_try; info->is_hs_configured = adapter->is_hs_configured; info->hs_activated = adapter->hs_activated; info->is_cmd_timedout = adapter->is_cmd_timedout; info->num_cmd_host_to_card_failure = adapter->dbg.num_cmd_host_to_card_failure; info->num_cmd_sleep_cfm_host_to_card_failure = adapter->dbg.num_cmd_sleep_cfm_host_to_card_failure; info->num_tx_host_to_card_failure = adapter->dbg.num_tx_host_to_card_failure; info->num_event_deauth = adapter->dbg.num_event_deauth; info->num_event_disassoc = adapter->dbg.num_event_disassoc; info->num_event_link_lost = adapter->dbg.num_event_link_lost; info->num_cmd_deauth = adapter->dbg.num_cmd_deauth; info->num_cmd_assoc_success = adapter->dbg.num_cmd_assoc_success; info->num_cmd_assoc_failure = adapter->dbg.num_cmd_assoc_failure; info->num_tx_timeout = adapter->dbg.num_tx_timeout; info->timeout_cmd_id = adapter->dbg.timeout_cmd_id; info->timeout_cmd_act = adapter->dbg.timeout_cmd_act; memcpy(info->last_cmd_id, adapter->dbg.last_cmd_id, sizeof(adapter->dbg.last_cmd_id)); memcpy(info->last_cmd_act, adapter->dbg.last_cmd_act, sizeof(adapter->dbg.last_cmd_act)); info->last_cmd_index = adapter->dbg.last_cmd_index; memcpy(info->last_cmd_resp_id, adapter->dbg.last_cmd_resp_id, sizeof(adapter->dbg.last_cmd_resp_id)); info->last_cmd_resp_index = adapter->dbg.last_cmd_resp_index; memcpy(info->last_event, adapter->dbg.last_event, sizeof(adapter->dbg.last_event)); info->last_event_index = adapter->dbg.last_event_index; info->data_sent = adapter->data_sent; info->cmd_sent = adapter->cmd_sent; info->cmd_resp_received = adapter->cmd_resp_received; } return 0; } int mwifiex_debug_info_to_buffer(struct mwifiex_private *priv, char *buf, struct mwifiex_debug_info *info) { char *p = buf; struct mwifiex_debug_data *d = &items[0]; size_t size, addr; long val; int i, j; if (!info) return 0; for (i = 0; i < num_of_items; i++) { p += sprintf(p, "%s=", d[i].name); size = d[i].size / d[i].num; if (i < (num_of_items - 3)) addr = d[i].addr + (size_t)info; else /* The last 3 items are struct mwifiex_adapter variables */ addr = d[i].addr + (size_t)priv->adapter; for (j = 0; j < d[i].num; j++) { switch (size) { case 1: val = *((u8 *)addr); break; case 2: val = *((u16 *)addr); break; case 4: val = *((u32 *)addr); break; case 8: val = *((long long *)addr); break; default: val = -1; break; } p += sprintf(p, "%#lx ", val); addr += size; } p += sprintf(p, "\n"); } if (info->tx_tbl_num) { p += sprintf(p, "Tx BA stream table:\n"); for (i = 0; i < info->tx_tbl_num; i++) p += sprintf(p, "tid = %d, ra = %pM\n", info->tx_tbl[i].tid, info->tx_tbl[i].ra); } if (info->rx_tbl_num) { p += sprintf(p, "Rx reorder table:\n"); for (i = 0; i < info->rx_tbl_num; i++) { p += sprintf(p, "tid = %d, ta = %pM, ", info->rx_tbl[i].tid, info->rx_tbl[i].ta); p += sprintf(p, "start_win = %d, ", info->rx_tbl[i].start_win); p += sprintf(p, "win_size = %d, buffer: ", info->rx_tbl[i].win_size); for (j = 0; j < info->rx_tbl[i].win_size; j++) p += sprintf(p, "%c ", info->rx_tbl[i].buffer[j] ? '1' : '0'); p += sprintf(p, "\n"); } } if (info->tdls_peer_num) { p += sprintf(p, "TDLS peer table:\n"); for (i = 0; i < info->tdls_peer_num; i++) { p += sprintf(p, "peer = %pM", info->tdls_list[i].peer_addr); p += sprintf(p, "\n"); } } return p - buf; } static int mwifiex_parse_mgmt_packet(struct mwifiex_private *priv, u8 *payload, u16 len, struct rxpd *rx_pd) { u16 stype; u8 category, action_code, *addr2; struct ieee80211_hdr *ieee_hdr = (void *)payload; stype = (le16_to_cpu(ieee_hdr->frame_control) & IEEE80211_FCTL_STYPE); switch (stype) { case IEEE80211_STYPE_ACTION: category = *(payload + sizeof(struct ieee80211_hdr)); switch (category) { case WLAN_CATEGORY_PUBLIC: action_code = *(payload + sizeof(struct ieee80211_hdr) + 1); if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) { addr2 = ieee_hdr->addr2; mwifiex_dbg(priv->adapter, INFO, "TDLS discovery response %pM nf=%d, snr=%d\n", addr2, rx_pd->nf, rx_pd->snr); mwifiex_auto_tdls_update_peer_signal(priv, addr2, rx_pd->snr, rx_pd->nf); } break; case WLAN_CATEGORY_BACK: /*we dont indicate BACK action frames to cfg80211*/ mwifiex_dbg(priv->adapter, INFO, "drop BACK action frames"); return -1; default: mwifiex_dbg(priv->adapter, INFO, "unknown public action frame category %d\n", category); } default: mwifiex_dbg(priv->adapter, INFO, "unknown mgmt frame subtype %#x\n", stype); return 0; } return 0; } /* * This function processes the received management packet and send it * to the kernel. */ int mwifiex_process_mgmt_packet(struct mwifiex_private *priv, struct sk_buff *skb) { struct rxpd *rx_pd; u16 pkt_len; struct ieee80211_hdr *ieee_hdr; if (!skb) return -1; if (!priv->mgmt_frame_mask || priv->wdev.iftype == NL80211_IFTYPE_UNSPECIFIED) { mwifiex_dbg(priv->adapter, ERROR, "do not receive mgmt frames on uninitialized intf"); return -1; } rx_pd = (struct rxpd *)skb->data; skb_pull(skb, le16_to_cpu(rx_pd->rx_pkt_offset)); skb_pull(skb, sizeof(pkt_len)); pkt_len = le16_to_cpu(rx_pd->rx_pkt_length); ieee_hdr = (void *)skb->data; if (ieee80211_is_mgmt(ieee_hdr->frame_control)) { if (mwifiex_parse_mgmt_packet(priv, (u8 *)ieee_hdr, pkt_len, rx_pd)) return -1; } /* Remove address4 */ memmove(skb->data + sizeof(struct ieee80211_hdr_3addr), skb->data + sizeof(struct ieee80211_hdr), pkt_len - sizeof(struct ieee80211_hdr)); pkt_len -= ETH_ALEN + sizeof(pkt_len); rx_pd->rx_pkt_length = cpu_to_le16(pkt_len); cfg80211_rx_mgmt(&priv->wdev, priv->roc_cfg.chan.center_freq, CAL_RSSI(rx_pd->snr, rx_pd->nf), skb->data, pkt_len, 0); return 0; } /* * This function processes the received packet before sending it to the * kernel. * * It extracts the SKB from the received buffer and sends it to kernel. * In case the received buffer does not contain the data in SKB format, * the function creates a blank SKB, fills it with the data from the * received buffer and then sends this new SKB to the kernel. */ int mwifiex_recv_packet(struct mwifiex_private *priv, struct sk_buff *skb) { struct mwifiex_sta_node *src_node; struct ethhdr *p_ethhdr; if (!skb) return -1; priv->stats.rx_bytes += skb->len; priv->stats.rx_packets++; if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_UAP) { p_ethhdr = (void *)skb->data; src_node = mwifiex_get_sta_entry(priv, p_ethhdr->h_source); if (src_node) { src_node->stats.last_rx = jiffies; src_node->stats.rx_bytes += skb->len; src_node->stats.rx_packets++; } } skb->dev = priv->netdev; skb->protocol = eth_type_trans(skb, priv->netdev); skb->ip_summed = CHECKSUM_NONE; /* This is required only in case of 11n and USB/PCIE as we alloc * a buffer of 4K only if its 11N (to be able to receive 4K * AMSDU packets). In case of SD we allocate buffers based * on the size of packet and hence this is not needed. * * Modifying the truesize here as our allocation for each * skb is 4K but we only receive 2K packets and this cause * the kernel to start dropping packets in case where * application has allocated buffer based on 2K size i.e. * if there a 64K packet received (in IP fragments and * application allocates 64K to receive this packet but * this packet would almost double up because we allocate * each 1.5K fragment in 4K and pass it up. As soon as the * 64K limit hits kernel will start to drop rest of the * fragments. Currently we fail the Filesndl-ht.scr script * for UDP, hence this fix */ if ((priv->adapter->iface_type == MWIFIEX_USB || priv->adapter->iface_type == MWIFIEX_PCIE) && (skb->truesize > MWIFIEX_RX_DATA_BUF_SIZE)) skb->truesize += (skb->len - MWIFIEX_RX_DATA_BUF_SIZE); if (in_interrupt()) netif_rx(skb); else netif_rx_ni(skb); return 0; } /* * IOCTL completion callback handler. * * This function is called when a pending IOCTL is completed. * * If work queue support is enabled, the function wakes up the * corresponding waiting function. Otherwise, it processes the * IOCTL response and frees the response buffer. */ int mwifiex_complete_cmd(struct mwifiex_adapter *adapter, struct cmd_ctrl_node *cmd_node) { mwifiex_dbg(adapter, CMD, "cmd completed: status=%d\n", adapter->cmd_wait_q.status); *(cmd_node->condition) = true; if (adapter->cmd_wait_q.status == -ETIMEDOUT) mwifiex_dbg(adapter, ERROR, "cmd timeout\n"); else wake_up_interruptible(&adapter->cmd_wait_q.wait); return 0; } /* This function will return the pointer to station entry in station list * table which matches specified mac address. * This function should be called after acquiring RA list spinlock. * NULL is returned if station entry is not found in associated STA list. */ struct mwifiex_sta_node * mwifiex_get_sta_entry(struct mwifiex_private *priv, const u8 *mac) { struct mwifiex_sta_node *node; if (!mac) return NULL; list_for_each_entry(node, &priv->sta_list, list) { if (!memcmp(node->mac_addr, mac, ETH_ALEN)) return node; } return NULL; } static struct mwifiex_sta_node * mwifiex_get_tdls_sta_entry(struct mwifiex_private *priv, u8 status) { struct mwifiex_sta_node *node; list_for_each_entry(node, &priv->sta_list, list) { if (node->tdls_status == status) return node; } return NULL; } /* If tdls channel switching is on-going, tx data traffic should be * blocked until the switching stage completed. */ u8 mwifiex_is_tdls_chan_switching(struct mwifiex_private *priv) { struct mwifiex_sta_node *sta_ptr; if (!priv || !ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info)) return false; sta_ptr = mwifiex_get_tdls_sta_entry(priv, TDLS_CHAN_SWITCHING); if (sta_ptr) return true; return false; } u8 mwifiex_is_tdls_off_chan(struct mwifiex_private *priv) { struct mwifiex_sta_node *sta_ptr; if (!priv || !ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info)) return false; sta_ptr = mwifiex_get_tdls_sta_entry(priv, TDLS_IN_OFF_CHAN); if (sta_ptr) return true; return false; } /* If tdls channel switching is on-going or tdls operate on off-channel, * cmd path should be blocked until tdls switched to base-channel. */ u8 mwifiex_is_send_cmd_allowed(struct mwifiex_private *priv) { if (!priv || !ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info)) return true; if (mwifiex_is_tdls_chan_switching(priv) || mwifiex_is_tdls_off_chan(priv)) return false; return true; } /* This function will add a sta_node entry to associated station list * table with the given mac address. * If entry exist already, existing entry is returned. * If received mac address is NULL, NULL is returned. */ struct mwifiex_sta_node * mwifiex_add_sta_entry(struct mwifiex_private *priv, const u8 *mac) { struct mwifiex_sta_node *node; unsigned long flags; if (!mac) return NULL; spin_lock_irqsave(&priv->sta_list_spinlock, flags); node = mwifiex_get_sta_entry(priv, mac); if (node) goto done; node = kzalloc(sizeof(*node), GFP_ATOMIC); if (!node) goto done; memcpy(node->mac_addr, mac, ETH_ALEN); list_add_tail(&node->list, &priv->sta_list); done: spin_unlock_irqrestore(&priv->sta_list_spinlock, flags); return node; } /* This function will search for HT IE in association request IEs * and set station HT parameters accordingly. */ void mwifiex_set_sta_ht_cap(struct mwifiex_private *priv, const u8 *ies, int ies_len, struct mwifiex_sta_node *node) { struct ieee_types_header *ht_cap_ie; const struct ieee80211_ht_cap *ht_cap; if (!ies) return; ht_cap_ie = (void *)cfg80211_find_ie(WLAN_EID_HT_CAPABILITY, ies, ies_len); if (ht_cap_ie) { ht_cap = (void *)(ht_cap_ie + 1); node->is_11n_enabled = 1; node->max_amsdu = le16_to_cpu(ht_cap->cap_info) & IEEE80211_HT_CAP_MAX_AMSDU ? MWIFIEX_TX_DATA_BUF_SIZE_8K : MWIFIEX_TX_DATA_BUF_SIZE_4K; } else { node->is_11n_enabled = 0; } return; } /* This function will delete a station entry from station list */ void mwifiex_del_sta_entry(struct mwifiex_private *priv, const u8 *mac) { struct mwifiex_sta_node *node; unsigned long flags; spin_lock_irqsave(&priv->sta_list_spinlock, flags); node = mwifiex_get_sta_entry(priv, mac); if (node) { list_del(&node->list); kfree(node); } spin_unlock_irqrestore(&priv->sta_list_spinlock, flags); return; } /* This function will delete all stations from associated station list. */ void mwifiex_del_all_sta_list(struct mwifiex_private *priv) { struct mwifiex_sta_node *node, *tmp; unsigned long flags; spin_lock_irqsave(&priv->sta_list_spinlock, flags); list_for_each_entry_safe(node, tmp, &priv->sta_list, list) { list_del(&node->list); kfree(node); } INIT_LIST_HEAD(&priv->sta_list); spin_unlock_irqrestore(&priv->sta_list_spinlock, flags); return; } /* This function adds histogram data to histogram array*/ void mwifiex_hist_data_add(struct mwifiex_private *priv, u8 rx_rate, s8 snr, s8 nflr) { struct mwifiex_histogram_data *phist_data = priv->hist_data; if (atomic_read(&phist_data->num_samples) > MWIFIEX_HIST_MAX_SAMPLES) mwifiex_hist_data_reset(priv); mwifiex_hist_data_set(priv, rx_rate, snr, nflr); } /* function to add histogram record */ void mwifiex_hist_data_set(struct mwifiex_private *priv, u8 rx_rate, s8 snr, s8 nflr) { struct mwifiex_histogram_data *phist_data = priv->hist_data; atomic_inc(&phist_data->num_samples); atomic_inc(&phist_data->rx_rate[rx_rate]); atomic_inc(&phist_data->snr[snr]); atomic_inc(&phist_data->noise_flr[128 + nflr]); atomic_inc(&phist_data->sig_str[nflr - snr]); } /* function to reset histogram data during init/reset */ void mwifiex_hist_data_reset(struct mwifiex_private *priv) { int ix; struct mwifiex_histogram_data *phist_data = priv->hist_data; atomic_set(&phist_data->num_samples, 0); for (ix = 0; ix < MWIFIEX_MAX_AC_RX_RATES; ix++) atomic_set(&phist_data->rx_rate[ix], 0); for (ix = 0; ix < MWIFIEX_MAX_SNR; ix++) atomic_set(&phist_data->snr[ix], 0); for (ix = 0; ix < MWIFIEX_MAX_NOISE_FLR; ix++) atomic_set(&phist_data->noise_flr[ix], 0); for (ix = 0; ix < MWIFIEX_MAX_SIG_STRENGTH; ix++) atomic_set(&phist_data->sig_str[ix], 0); } void *mwifiex_alloc_dma_align_buf(int rx_len, gfp_t flags) { struct sk_buff *skb; int buf_len, pad; buf_len = rx_len + MWIFIEX_RX_HEADROOM + MWIFIEX_DMA_ALIGN_SZ; skb = __dev_alloc_skb(buf_len, flags); if (!skb) return NULL; skb_reserve(skb, MWIFIEX_RX_HEADROOM); pad = MWIFIEX_ALIGN_ADDR(skb->data, MWIFIEX_DMA_ALIGN_SZ) - (long)skb->data; skb_reserve(skb, pad); return skb; } EXPORT_SYMBOL_GPL(mwifiex_alloc_dma_align_buf);