/*- * Based on BSD-licensed source modules in the Linux iwlwifi driver, * which were used as the reference documentation for this implementation. * * Driver version we are currently based off of is * Linux 4.7.3 (tag id d7f6728f57e3ecbb7ef34eb7d9f564d514775d75) * *********************************************************************** * * * This file is provided under a dual BSD/GPLv2 license. When using or * redistributing this file, you may do so under either license. * * GPL LICENSE SUMMARY * * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved. * Copyright(c) 2013 - 2014 Intel Mobile Communications GmbH * Copyright(c) 2015 - 2016 Intel Deutschland GmbH * * This program is free software; you can redistribute it and/or modify * it under the terms of version 2 of the GNU General Public License as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, * USA * * The full GNU General Public License is included in this distribution * in the file called COPYING. * * Contact Information: * Intel Linux Wireless * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 * * BSD LICENSE * * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved. * Copyright(c) 2013 - 2014 Intel Mobile Communications GmbH * Copyright(c) 2015 - 2016 Intel Deutschland GmbH * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name Intel Corporation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * *****************************************************************************/ /* $FreeBSD$ */ #ifndef __IF_IWM_STA_H__ #define __IF_IWM_STA_H__ /** * DOC: station table - introduction * * The station table is a list of data structure that reprensent the stations. * In STA/P2P client mode, the driver will hold one station for the AP/ GO. * In GO/AP mode, the driver will have as many stations as associated clients. * All these stations are reflected in the fw's station table. The driver * keeps the fw's station table up to date with the ADD_STA command. Stations * can be removed by the REMOVE_STA command. * * All the data related to a station is held in the structure %iwl_sta * which is embed in the mac80211's %ieee80211_sta (in the drv_priv) area. * This data includes the index of the station in the fw, per tid information * (sequence numbers, Block-ack state machine, etc...). The stations are * created and deleted by the %sta_state callback from %ieee80211_ops. * * The driver holds a map: %fw_id_to_mac_id that allows to fetch a * %ieee80211_sta (and the %iwl_sta embedded into it) based on a fw * station index. That way, the driver is able to get the tid related data in * O(1) in time sensitive paths (Tx / Tx response / BA notification). These * paths are triggered by the fw, and the driver needs to get a pointer to the * %ieee80211 structure. This map helps to get that pointer quickly. */ /** * DOC: station table - locking * * As stated before, the station is created / deleted by mac80211's %sta_state * callback from %ieee80211_ops which can sleep. The next paragraph explains * the locking of a single stations, the next ones relates to the station * table. * * The station holds the sequence number per tid. So this data needs to be * accessed in the Tx path (which is softIRQ). It also holds the Block-Ack * information (the state machine / and the logic that checks if the queues * were drained), so it also needs to be accessible from the Tx response flow. * In short, the station needs to be access from sleepable context as well as * from tasklets, so the station itself needs a spinlock. * * The writers of %fw_id_to_mac_id map are serialized by the global mutex of * the mvm op_mode. This is possible since %sta_state can sleep. * The pointers in this map are RCU protected, hence we won't replace the * station while we have Tx / Tx response / BA notification running. * * If a station is deleted while it still has packets in its A-MPDU queues, * then the reclaim flow will notice that there is no station in the map for * sta_id and it will dump the responses. */ /** * DOC: station table - internal stations * * The FW needs a few internal stations that are not reflected in * mac80211, such as broadcast station in AP / GO mode, or AUX sta for * scanning and P2P device (during the GO negotiation). * For these kind of stations we have %iwl_int_sta struct which holds the * data relevant for them from both %iwl_sta and %ieee80211_sta. * Usually the data for these stations is static, so no locking is required, * and no TID data as this is also not needed. * One thing to note, is that these stations have an ID in the fw, but not * in mac80211. In order to "reserve" them a sta_id in %fw_id_to_mac_id * we fill ERR_PTR(EINVAL) in this mapping and all other dereferencing of * pointers from this mapping need to check that the value is not error * or NULL. * * Currently there is only one auxiliary station for scanning, initialized * on init. */ /** * DOC: station table - AP Station in STA mode * * %iwl_vif includes the index of the AP station in the fw's STA table: * %ap_sta_id. To get the point to the corresponding %ieee80211_sta, * &fw_id_to_mac_id can be used. Due to the way the fw works, we must not remove * the AP station from the fw before setting the MAC context as unassociated. * Hence, %fw_id_to_mac_id[%ap_sta_id] will be NULLed when the AP station is * removed by mac80211, but the station won't be removed in the fw until the * VIF is set as unassociated. Then, %ap_sta_id will be invalidated. */ /** * DOC: station table - Drain vs. Flush * * Flush means that all the frames in the SCD queue are dumped regardless the * station to which they were sent. We do that when we disassociate and before * we remove the STA of the AP. The flush can be done synchronously against the * fw. * Drain means that the fw will drop all the frames sent to a specific station. * This is useful when a client (if we are IBSS / GO or AP) disassociates. In * that case, we need to drain all the frames for that client from the AC queues * that are shared with the other clients. Only then, we can remove the STA in * the fw. In order to do so, we track the non-AMPDU packets for each station. * If mac80211 removes a STA and if it still has non-AMPDU packets pending in * the queues, we mark this station as %EBUSY in %fw_id_to_mac_id, and drop all * the frames for this STA (%iwl_rm_sta). When the last frame is dropped * (we know about it with its Tx response), we remove the station in fw and set * it as %NULL in %fw_id_to_mac_id: this is the purpose of * %iwl_sta_drained_wk. */ /** * DOC: station table - fw restart * * When the fw asserts, or we have any other issue that requires to reset the * driver, we require mac80211 to reconfigure the driver. Since the private * data of the stations is embed in mac80211's %ieee80211_sta, that data will * not be zeroed and needs to be reinitialized manually. * %IWL_STATUS_IN_HW_RESTART is set during restart and that will hint us * that we must not allocate a new sta_id but reuse the previous one. This * means that the stations being re-added after the reset will have the same * place in the fw as before the reset. We do need to zero the %fw_id_to_mac_id * map, since the stations aren't in the fw any more. Internal stations that * are not added by mac80211 will be re-added in the init flow that is called * after the restart: mac80211 call's %iwl_mac_start which calls to * %iwl_up. */ /** * Send the STA info to the FW. * * @sc: the iwm_softc* to use * @sta: the STA * @update: this is true if the FW is being updated about a STA it already knows * about. Otherwise (if this is a new STA), this should be false. * @flags: if update==true, this marks what is being changed via ORs of values * from enum iwm_sta_modify_flag. Otherwise, this is ignored. */ extern int iwm_sta_send_to_fw(struct iwm_softc *sc, struct iwm_node *in, boolean_t update); extern int iwm_add_sta(struct iwm_softc *sc, struct iwm_node *in); extern int iwm_update_sta(struct iwm_softc *sc, struct iwm_node *in); extern int iwm_rm_sta(struct iwm_softc *sc, struct ieee80211vap *vap, boolean_t is_assoc); extern int iwm_rm_sta_id(struct iwm_softc *sc, struct ieee80211vap *vap); extern int iwm_add_aux_sta(struct iwm_softc *sc); extern void iwm_del_aux_sta(struct iwm_softc *sc); extern int iwm_drain_sta(struct iwm_softc *sc, struct iwm_vap *ivp, boolean_t drain); #endif /* __IF_IWM_STA_H__ */