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67 
68 #ifndef __sta_h__
69 #define __sta_h__
70 
71 #include <linux/spinlock.h>
72 #include <net/mac80211.h>
73 #include <linux/wait.h>
74 
75 #include "iwl-trans.h" /* for IWL_MAX_TID_COUNT */
76 #include "fw-api.h" /* IWL_MVM_STATION_COUNT */
77 #include "rs.h"
78 
79 struct iwl_mvm;
80 struct iwl_mvm_vif;
81 
82 /**
83  * DOC: station table - introduction
84  *
85  * The station table is a list of data structure that reprensent the stations.
86  * In STA/P2P client mode, the driver will hold one station for the AP/ GO.
87  * In GO/AP mode, the driver will have as many stations as associated clients.
88  * All these stations are reflected in the fw's station table. The driver
89  * keeps the fw's station table up to date with the ADD_STA command. Stations
90  * can be removed by the REMOVE_STA command.
91  *
92  * All the data related to a station is held in the structure %iwl_mvm_sta
93  * which is embed in the mac80211's %ieee80211_sta (in the drv_priv) area.
94  * This data includes the index of the station in the fw, per tid information
95  * (sequence numbers, Block-ack state machine, etc...). The stations are
96  * created and deleted by the %sta_state callback from %ieee80211_ops.
97  *
98  * The driver holds a map: %fw_id_to_mac_id that allows to fetch a
99  * %ieee80211_sta (and the %iwl_mvm_sta embedded into it) based on a fw
100  * station index. That way, the driver is able to get the tid related data in
101  * O(1) in time sensitive paths (Tx / Tx response / BA notification). These
102  * paths are triggered by the fw, and the driver needs to get a pointer to the
103  * %ieee80211 structure. This map helps to get that pointer quickly.
104  */
105 
106 /**
107  * DOC: station table - locking
108  *
109  * As stated before, the station is created / deleted by mac80211's %sta_state
110  * callback from %ieee80211_ops which can sleep. The next paragraph explains
111  * the locking of a single stations, the next ones relates to the station
112  * table.
113  *
114  * The station holds the sequence number per tid. So this data needs to be
115  * accessed in the Tx path (which is softIRQ). It also holds the Block-Ack
116  * information (the state machine / and the logic that checks if the queues
117  * were drained), so it also needs to be accessible from the Tx response flow.
118  * In short, the station needs to be access from sleepable context as well as
119  * from tasklets, so the station itself needs a spinlock.
120  *
121  * The writers of %fw_id_to_mac_id map are serialized by the global mutex of
122  * the mvm op_mode. This is possible since %sta_state can sleep.
123  * The pointers in this map are RCU protected, hence we won't replace the
124  * station while we have Tx / Tx response / BA notification running.
125  *
126  * If a station is deleted while it still has packets in its A-MPDU queues,
127  * then the reclaim flow will notice that there is no station in the map for
128  * sta_id and it will dump the responses.
129  */
130 
131 /**
132  * DOC: station table - internal stations
133  *
134  * The FW needs a few internal stations that are not reflected in
135  * mac80211, such as broadcast station in AP / GO mode, or AUX sta for
136  * scanning and P2P device (during the GO negotiation).
137  * For these kind of stations we have %iwl_mvm_int_sta struct which holds the
138  * data relevant for them from both %iwl_mvm_sta and %ieee80211_sta.
139  * Usually the data for these stations is static, so no locking is required,
140  * and no TID data as this is also not needed.
141  * One thing to note, is that these stations have an ID in the fw, but not
142  * in mac80211. In order to "reserve" them a sta_id in %fw_id_to_mac_id
143  * we fill ERR_PTR(EINVAL) in this mapping and all other dereferencing of
144  * pointers from this mapping need to check that the value is not error
145  * or NULL.
146  *
147  * Currently there is only one auxiliary station for scanning, initialized
148  * on init.
149  */
150 
151 /**
152  * DOC: station table - AP Station in STA mode
153  *
154  * %iwl_mvm_vif includes the index of the AP station in the fw's STA table:
155  * %ap_sta_id. To get the point to the corresponding %ieee80211_sta,
156  * &fw_id_to_mac_id can be used. Due to the way the fw works, we must not remove
157  * the AP station from the fw before setting the MAC context as unassociated.
158  * Hence, %fw_id_to_mac_id[%ap_sta_id] will be NULLed when the AP station is
159  * removed by mac80211, but the station won't be removed in the fw until the
160  * VIF is set as unassociated. Then, %ap_sta_id will be invalidated.
161  */
162 
163 /**
164  * DOC: station table - Drain vs. Flush
165  *
166  * Flush means that all the frames in the SCD queue are dumped regardless the
167  * station to which they were sent. We do that when we disassociate and before
168  * we remove the STA of the AP. The flush can be done synchronously against the
169  * fw.
170  * Drain means that the fw will drop all the frames sent to a specific station.
171  * This is useful when a client (if we are IBSS / GO or AP) disassociates. In
172  * that case, we need to drain all the frames for that client from the AC queues
173  * that are shared with the other clients. Only then, we can remove the STA in
174  * the fw. In order to do so, we track the non-AMPDU packets for each station.
175  * If mac80211 removes a STA and if it still has non-AMPDU packets pending in
176  * the queues, we mark this station as %EBUSY in %fw_id_to_mac_id, and drop all
177  * the frames for this STA (%iwl_mvm_rm_sta). When the last frame is dropped
178  * (we know about it with its Tx response), we remove the station in fw and set
179  * it as %NULL in %fw_id_to_mac_id: this is the purpose of
180  * %iwl_mvm_sta_drained_wk.
181  */
182 
183 /**
184  * DOC: station table - fw restart
185  *
186  * When the fw asserts, or we have any other issue that requires to reset the
187  * driver, we require mac80211 to reconfigure the driver. Since the private
188  * data of the stations is embed in mac80211's %ieee80211_sta, that data will
189  * not be zeroed and needs to be reinitialized manually.
190  * %IWL_MVM_STATUS_IN_HW_RESTART is set during restart and that will hint us
191  * that we must not allocate a new sta_id but reuse the previous one. This
192  * means that the stations being re-added after the reset will have the same
193  * place in the fw as before the reset. We do need to zero the %fw_id_to_mac_id
194  * map, since the stations aren't in the fw any more. Internal stations that
195  * are not added by mac80211 will be re-added in the init flow that is called
196  * after the restart: mac80211 call's %iwl_mvm_mac_start which calls to
197  * %iwl_mvm_up.
198  */
199 
200 /**
201  * DOC: AP mode - PS
202  *
203  * When a station is asleep, the fw will set it as "asleep". All frames on
204  * shared queues (i.e. non-aggregation queues) to that station will be dropped
205  * by the fw (%TX_STATUS_FAIL_DEST_PS failure code).
206  *
207  * AMPDUs are in a separate queue that is stopped by the fw. We just need to
208  * let mac80211 know when there are frames in these queues so that it can
209  * properly handle trigger frames.
210  *
211  * When a trigger frame is received, mac80211 tells the driver to send frames
212  * from the AMPDU queues or sends frames to non-aggregation queues itself,
213  * depending on which ACs are delivery-enabled and what TID has frames to
214  * transmit. Note that mac80211 has all the knowledge since all the non-agg
215  * frames are buffered / filtered, and the driver tells mac80211 about agg
216  * frames). The driver needs to tell the fw to let frames out even if the
217  * station is asleep. This is done by %iwl_mvm_sta_modify_sleep_tx_count.
218  *
219  * When we receive a frame from that station with PM bit unset, the driver
220  * needs to let the fw know that this station isn't asleep any more. This is
221  * done by %iwl_mvm_sta_modify_ps_wake in response to mac80211 signaling the
222  * station's wakeup.
223  *
224  * For a GO, the Service Period might be cut short due to an absence period
225  * of the GO. In this (and all other cases) the firmware notifies us with the
226  * EOSP_NOTIFICATION, and we notify mac80211 of that. Further frames that we
227  * already sent to the device will be rejected again.
228  *
229  * See also "AP support for powersaving clients" in mac80211.h.
230  */
231 
232 /**
233  * enum iwl_mvm_agg_state
234  *
235  * The state machine of the BA agreement establishment / tear down.
236  * These states relate to a specific RA / TID.
237  *
238  * @IWL_AGG_OFF: aggregation is not used
239  * @IWL_AGG_STARTING: aggregation are starting (between start and oper)
240  * @IWL_AGG_ON: aggregation session is up
241  * @IWL_EMPTYING_HW_QUEUE_ADDBA: establishing a BA session - waiting for the
242  *	HW queue to be empty from packets for this RA /TID.
243  * @IWL_EMPTYING_HW_QUEUE_DELBA: tearing down a BA session - waiting for the
244  *	HW queue to be empty from packets for this RA /TID.
245  */
246 enum iwl_mvm_agg_state {
247 	IWL_AGG_OFF = 0,
248 	IWL_AGG_STARTING,
249 	IWL_AGG_ON,
250 	IWL_EMPTYING_HW_QUEUE_ADDBA,
251 	IWL_EMPTYING_HW_QUEUE_DELBA,
252 };
253 
254 /**
255  * struct iwl_mvm_tid_data - holds the states for each RA / TID
256  * @seq_number: the next WiFi sequence number to use
257  * @next_reclaimed: the WiFi sequence number of the next packet to be acked.
258  *	This is basically (last acked packet++).
259  * @rate_n_flags: Rate at which Tx was attempted. Holds the data between the
260  *	Tx response (TX_CMD), and the block ack notification (COMPRESSED_BA).
261  * @amsdu_in_ampdu_allowed: true if A-MSDU in A-MPDU is allowed.
262  * @state: state of the BA agreement establishment / tear down.
263  * @txq_id: Tx queue used by the BA session
264  * @ssn: the first packet to be sent in AGG HW queue in Tx AGG start flow, or
265  *	the first packet to be sent in legacy HW queue in Tx AGG stop flow.
266  *	Basically when next_reclaimed reaches ssn, we can tell mac80211 that
267  *	we are ready to finish the Tx AGG stop / start flow.
268  * @tx_time: medium time consumed by this A-MPDU
269  */
270 struct iwl_mvm_tid_data {
271 	u16 seq_number;
272 	u16 next_reclaimed;
273 	/* The rest is Tx AGG related */
274 	u32 rate_n_flags;
275 	bool amsdu_in_ampdu_allowed;
276 	enum iwl_mvm_agg_state state;
277 	u16 txq_id;
278 	u16 ssn;
279 	u16 tx_time;
280 };
281 
282 static inline u16 iwl_mvm_tid_queued(struct iwl_mvm_tid_data *tid_data)
283 {
284 	return ieee80211_sn_sub(IEEE80211_SEQ_TO_SN(tid_data->seq_number),
285 				tid_data->next_reclaimed);
286 }
287 
288 struct iwl_mvm_key_pn {
289 	struct rcu_head rcu_head;
290 	struct {
291 		u8 pn[IWL_MAX_TID_COUNT][IEEE80211_CCMP_PN_LEN];
292 	} ____cacheline_aligned_in_smp q[];
293 };
294 
295 /**
296  * struct iwl_mvm_rxq_dup_data - per station per rx queue data
297  * @last_seq: last sequence per tid for duplicate packet detection
298  * @last_sub_frame: last subframe packet
299  */
300 struct iwl_mvm_rxq_dup_data {
301 	__le16 last_seq[IWL_MAX_TID_COUNT + 1];
302 	u8 last_sub_frame[IWL_MAX_TID_COUNT + 1];
303 } ____cacheline_aligned_in_smp;
304 
305 /**
306  * struct iwl_mvm_sta - representation of a station in the driver
307  * @sta_id: the index of the station in the fw (will be replaced by id_n_color)
308  * @tfd_queue_msk: the tfd queues used by the station
309  * @hw_queue: per-AC mapping of the TFD queues used by station
310  * @mac_id_n_color: the MAC context this station is linked to
311  * @tid_disable_agg: bitmap: if bit(tid) is set, the fw won't send ampdus for
312  *	tid.
313  * @max_agg_bufsize: the maximal size of the AGG buffer for this station
314  * @bt_reduced_txpower: is reduced tx power enabled for this station
315  * @next_status_eosp: the next reclaimed packet is a PS-Poll response and
316  *	we need to signal the EOSP
317  * @lock: lock to protect the whole struct. Since %tid_data is access from Tx
318  * and from Tx response flow, it needs a spinlock.
319  * @tid_data: per tid data. Look at %iwl_mvm_tid_data.
320  * @tx_protection: reference counter for controlling the Tx protection.
321  * @tt_tx_protection: is thermal throttling enable Tx protection?
322  * @disable_tx: is tx to this STA disabled?
323  * @tlc_amsdu: true if A-MSDU is allowed
324  * @agg_tids: bitmap of tids whose status is operational aggregated (IWL_AGG_ON)
325  * @sleep_tx_count: the number of frames that we told the firmware to let out
326  *	even when that station is asleep. This is useful in case the queue
327  *	gets empty before all the frames were sent, which can happen when
328  *	we are sending frames from an AMPDU queue and there was a hole in
329  *	the BA window. To be used for UAPSD only.
330  * @ptk_pn: per-queue PTK PN data structures
331  * @dup_data: per queue duplicate packet detection data
332  *
333  * When mac80211 creates a station it reserves some space (hw->sta_data_size)
334  * in the structure for use by driver. This structure is placed in that
335  * space.
336  *
337  */
338 struct iwl_mvm_sta {
339 	u32 sta_id;
340 	u32 tfd_queue_msk;
341 	u8 hw_queue[IEEE80211_NUM_ACS];
342 	u32 mac_id_n_color;
343 	u16 tid_disable_agg;
344 	u8 max_agg_bufsize;
345 	bool bt_reduced_txpower;
346 	bool next_status_eosp;
347 	spinlock_t lock;
348 	struct iwl_mvm_tid_data tid_data[IWL_MAX_TID_COUNT];
349 	struct iwl_lq_sta lq_sta;
350 	struct ieee80211_vif *vif;
351 	struct iwl_mvm_key_pn __rcu *ptk_pn[4];
352 	struct iwl_mvm_rxq_dup_data *dup_data;
353 
354 	/* Temporary, until the new TLC will control the Tx protection */
355 	s8 tx_protection;
356 	bool tt_tx_protection;
357 
358 	bool disable_tx;
359 	bool tlc_amsdu;
360 	u8 agg_tids;
361 	u8 sleep_tx_count;
362 };
363 
364 static inline struct iwl_mvm_sta *
365 iwl_mvm_sta_from_mac80211(struct ieee80211_sta *sta)
366 {
367 	return (void *)sta->drv_priv;
368 }
369 
370 /**
371  * struct iwl_mvm_int_sta - representation of an internal station (auxiliary or
372  * broadcast)
373  * @sta_id: the index of the station in the fw (will be replaced by id_n_color)
374  * @tfd_queue_msk: the tfd queues used by the station
375  */
376 struct iwl_mvm_int_sta {
377 	u32 sta_id;
378 	u32 tfd_queue_msk;
379 };
380 
381 int iwl_mvm_sta_send_to_fw(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
382 			   bool update);
383 int iwl_mvm_add_sta(struct iwl_mvm *mvm,
384 		    struct ieee80211_vif *vif,
385 		    struct ieee80211_sta *sta);
386 int iwl_mvm_update_sta(struct iwl_mvm *mvm,
387 		       struct ieee80211_vif *vif,
388 		       struct ieee80211_sta *sta);
389 int iwl_mvm_rm_sta(struct iwl_mvm *mvm,
390 		   struct ieee80211_vif *vif,
391 		   struct ieee80211_sta *sta);
392 int iwl_mvm_rm_sta_id(struct iwl_mvm *mvm,
393 		      struct ieee80211_vif *vif,
394 		      u8 sta_id);
395 int iwl_mvm_set_sta_key(struct iwl_mvm *mvm,
396 			struct ieee80211_vif *vif,
397 			struct ieee80211_sta *sta,
398 			struct ieee80211_key_conf *keyconf,
399 			u8 key_offset);
400 int iwl_mvm_remove_sta_key(struct iwl_mvm *mvm,
401 			   struct ieee80211_vif *vif,
402 			   struct ieee80211_sta *sta,
403 			   struct ieee80211_key_conf *keyconf);
404 
405 void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm,
406 			     struct ieee80211_vif *vif,
407 			     struct ieee80211_key_conf *keyconf,
408 			     struct ieee80211_sta *sta, u32 iv32,
409 			     u16 *phase1key);
410 
411 void iwl_mvm_rx_eosp_notif(struct iwl_mvm *mvm,
412 			   struct iwl_rx_cmd_buffer *rxb);
413 
414 /* AMPDU */
415 int iwl_mvm_sta_rx_agg(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
416 		       int tid, u16 ssn, bool start, u8 buf_size);
417 int iwl_mvm_sta_tx_agg_start(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
418 			struct ieee80211_sta *sta, u16 tid, u16 *ssn);
419 int iwl_mvm_sta_tx_agg_oper(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
420 			    struct ieee80211_sta *sta, u16 tid, u8 buf_size,
421 			    bool amsdu);
422 int iwl_mvm_sta_tx_agg_stop(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
423 			    struct ieee80211_sta *sta, u16 tid);
424 int iwl_mvm_sta_tx_agg_flush(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
425 			    struct ieee80211_sta *sta, u16 tid);
426 
427 int iwl_mvm_add_aux_sta(struct iwl_mvm *mvm);
428 void iwl_mvm_del_aux_sta(struct iwl_mvm *mvm);
429 
430 int iwl_mvm_alloc_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
431 int iwl_mvm_send_add_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
432 int iwl_mvm_add_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
433 int iwl_mvm_send_rm_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
434 int iwl_mvm_rm_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
435 int iwl_mvm_allocate_int_sta(struct iwl_mvm *mvm,
436 			     struct iwl_mvm_int_sta *sta,
437 				    u32 qmask, enum nl80211_iftype iftype);
438 void iwl_mvm_dealloc_bcast_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
439 int iwl_mvm_add_snif_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
440 int iwl_mvm_rm_snif_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
441 void iwl_mvm_dealloc_snif_sta(struct iwl_mvm *mvm);
442 
443 void iwl_mvm_sta_drained_wk(struct work_struct *wk);
444 void iwl_mvm_sta_modify_ps_wake(struct iwl_mvm *mvm,
445 				struct ieee80211_sta *sta);
446 void iwl_mvm_sta_modify_sleep_tx_count(struct iwl_mvm *mvm,
447 				       struct ieee80211_sta *sta,
448 				       enum ieee80211_frame_release_type reason,
449 				       u16 cnt, u16 tids, bool more_data,
450 				       bool agg);
451 int iwl_mvm_drain_sta(struct iwl_mvm *mvm, struct iwl_mvm_sta *mvmsta,
452 		      bool drain);
453 void iwl_mvm_sta_modify_disable_tx(struct iwl_mvm *mvm,
454 				   struct iwl_mvm_sta *mvmsta, bool disable);
455 void iwl_mvm_sta_modify_disable_tx_ap(struct iwl_mvm *mvm,
456 				      struct ieee80211_sta *sta,
457 				      bool disable);
458 void iwl_mvm_modify_all_sta_disable_tx(struct iwl_mvm *mvm,
459 				       struct iwl_mvm_vif *mvmvif,
460 				       bool disable);
461 void iwl_mvm_csa_client_absent(struct iwl_mvm *mvm, struct ieee80211_vif *vif);
462 
463 #endif /* __sta_h__ */
464