xref: /openbmc/linux/net/mac80211/sta_info.h (revision 4f3db074)
1 /*
2  * Copyright 2002-2005, Devicescape Software, Inc.
3  * Copyright 2013-2014  Intel Mobile Communications GmbH
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #ifndef STA_INFO_H
11 #define STA_INFO_H
12 
13 #include <linux/list.h>
14 #include <linux/types.h>
15 #include <linux/if_ether.h>
16 #include <linux/workqueue.h>
17 #include <linux/average.h>
18 #include <linux/etherdevice.h>
19 #include <linux/rhashtable.h>
20 #include "key.h"
21 
22 /**
23  * enum ieee80211_sta_info_flags - Stations flags
24  *
25  * These flags are used with &struct sta_info's @flags member, but
26  * only indirectly with set_sta_flag() and friends.
27  *
28  * @WLAN_STA_AUTH: Station is authenticated.
29  * @WLAN_STA_ASSOC: Station is associated.
30  * @WLAN_STA_PS_STA: Station is in power-save mode
31  * @WLAN_STA_AUTHORIZED: Station is authorized to send/receive traffic.
32  *	This bit is always checked so needs to be enabled for all stations
33  *	when virtual port control is not in use.
34  * @WLAN_STA_SHORT_PREAMBLE: Station is capable of receiving short-preamble
35  *	frames.
36  * @WLAN_STA_WDS: Station is one of our WDS peers.
37  * @WLAN_STA_CLEAR_PS_FILT: Clear PS filter in hardware (using the
38  *	IEEE80211_TX_CTL_CLEAR_PS_FILT control flag) when the next
39  *	frame to this station is transmitted.
40  * @WLAN_STA_MFP: Management frame protection is used with this STA.
41  * @WLAN_STA_BLOCK_BA: Used to deny ADDBA requests (both TX and RX)
42  *	during suspend/resume and station removal.
43  * @WLAN_STA_PS_DRIVER: driver requires keeping this station in
44  *	power-save mode logically to flush frames that might still
45  *	be in the queues
46  * @WLAN_STA_PSPOLL: Station sent PS-poll while driver was keeping
47  *	station in power-save mode, reply when the driver unblocks.
48  * @WLAN_STA_TDLS_PEER: Station is a TDLS peer.
49  * @WLAN_STA_TDLS_PEER_AUTH: This TDLS peer is authorized to send direct
50  *	packets. This means the link is enabled.
51  * @WLAN_STA_TDLS_INITIATOR: We are the initiator of the TDLS link with this
52  *	station.
53  * @WLAN_STA_TDLS_CHAN_SWITCH: This TDLS peer supports TDLS channel-switching
54  * @WLAN_STA_TDLS_OFF_CHANNEL: The local STA is currently off-channel with this
55  *	TDLS peer
56  * @WLAN_STA_UAPSD: Station requested unscheduled SP while driver was
57  *	keeping station in power-save mode, reply when the driver
58  *	unblocks the station.
59  * @WLAN_STA_SP: Station is in a service period, so don't try to
60  *	reply to other uAPSD trigger frames or PS-Poll.
61  * @WLAN_STA_4ADDR_EVENT: 4-addr event was already sent for this frame.
62  * @WLAN_STA_INSERTED: This station is inserted into the hash table.
63  * @WLAN_STA_RATE_CONTROL: rate control was initialized for this station.
64  * @WLAN_STA_TOFFSET_KNOWN: toffset calculated for this station is valid.
65  * @WLAN_STA_MPSP_OWNER: local STA is owner of a mesh Peer Service Period.
66  * @WLAN_STA_MPSP_RECIPIENT: local STA is recipient of a MPSP.
67  * @WLAN_STA_PS_DELIVER: station woke up, but we're still blocking TX
68  *	until pending frames are delivered
69  */
70 enum ieee80211_sta_info_flags {
71 	WLAN_STA_AUTH,
72 	WLAN_STA_ASSOC,
73 	WLAN_STA_PS_STA,
74 	WLAN_STA_AUTHORIZED,
75 	WLAN_STA_SHORT_PREAMBLE,
76 	WLAN_STA_WDS,
77 	WLAN_STA_CLEAR_PS_FILT,
78 	WLAN_STA_MFP,
79 	WLAN_STA_BLOCK_BA,
80 	WLAN_STA_PS_DRIVER,
81 	WLAN_STA_PSPOLL,
82 	WLAN_STA_TDLS_PEER,
83 	WLAN_STA_TDLS_PEER_AUTH,
84 	WLAN_STA_TDLS_INITIATOR,
85 	WLAN_STA_TDLS_CHAN_SWITCH,
86 	WLAN_STA_TDLS_OFF_CHANNEL,
87 	WLAN_STA_UAPSD,
88 	WLAN_STA_SP,
89 	WLAN_STA_4ADDR_EVENT,
90 	WLAN_STA_INSERTED,
91 	WLAN_STA_RATE_CONTROL,
92 	WLAN_STA_TOFFSET_KNOWN,
93 	WLAN_STA_MPSP_OWNER,
94 	WLAN_STA_MPSP_RECIPIENT,
95 	WLAN_STA_PS_DELIVER,
96 };
97 
98 #define ADDBA_RESP_INTERVAL HZ
99 #define HT_AGG_MAX_RETRIES		15
100 #define HT_AGG_BURST_RETRIES		3
101 #define HT_AGG_RETRIES_PERIOD		(15 * HZ)
102 
103 #define HT_AGG_STATE_DRV_READY		0
104 #define HT_AGG_STATE_RESPONSE_RECEIVED	1
105 #define HT_AGG_STATE_OPERATIONAL	2
106 #define HT_AGG_STATE_STOPPING		3
107 #define HT_AGG_STATE_WANT_START		4
108 #define HT_AGG_STATE_WANT_STOP		5
109 
110 enum ieee80211_agg_stop_reason {
111 	AGG_STOP_DECLINED,
112 	AGG_STOP_LOCAL_REQUEST,
113 	AGG_STOP_PEER_REQUEST,
114 	AGG_STOP_DESTROY_STA,
115 };
116 
117 /**
118  * struct tid_ampdu_tx - TID aggregation information (Tx).
119  *
120  * @rcu_head: rcu head for freeing structure
121  * @session_timer: check if we keep Tx-ing on the TID (by timeout value)
122  * @addba_resp_timer: timer for peer's response to addba request
123  * @pending: pending frames queue -- use sta's spinlock to protect
124  * @dialog_token: dialog token for aggregation session
125  * @timeout: session timeout value to be filled in ADDBA requests
126  * @state: session state (see above)
127  * @last_tx: jiffies of last tx activity
128  * @stop_initiator: initiator of a session stop
129  * @tx_stop: TX DelBA frame when stopping
130  * @buf_size: reorder buffer size at receiver
131  * @failed_bar_ssn: ssn of the last failed BAR tx attempt
132  * @bar_pending: BAR needs to be re-sent
133  *
134  * This structure's lifetime is managed by RCU, assignments to
135  * the array holding it must hold the aggregation mutex.
136  *
137  * The TX path can access it under RCU lock-free if, and
138  * only if, the state has the flag %HT_AGG_STATE_OPERATIONAL
139  * set. Otherwise, the TX path must also acquire the spinlock
140  * and re-check the state, see comments in the tx code
141  * touching it.
142  */
143 struct tid_ampdu_tx {
144 	struct rcu_head rcu_head;
145 	struct timer_list session_timer;
146 	struct timer_list addba_resp_timer;
147 	struct sk_buff_head pending;
148 	unsigned long state;
149 	unsigned long last_tx;
150 	u16 timeout;
151 	u8 dialog_token;
152 	u8 stop_initiator;
153 	bool tx_stop;
154 	u8 buf_size;
155 
156 	u16 failed_bar_ssn;
157 	bool bar_pending;
158 };
159 
160 /**
161  * struct tid_ampdu_rx - TID aggregation information (Rx).
162  *
163  * @reorder_buf: buffer to reorder incoming aggregated MPDUs. An MPDU may be an
164  *	A-MSDU with individually reported subframes.
165  * @reorder_time: jiffies when skb was added
166  * @session_timer: check if peer keeps Tx-ing on the TID (by timeout value)
167  * @reorder_timer: releases expired frames from the reorder buffer.
168  * @last_rx: jiffies of last rx activity
169  * @head_seq_num: head sequence number in reordering buffer.
170  * @stored_mpdu_num: number of MPDUs in reordering buffer
171  * @ssn: Starting Sequence Number expected to be aggregated.
172  * @buf_size: buffer size for incoming A-MPDUs
173  * @timeout: reset timer value (in TUs).
174  * @dialog_token: dialog token for aggregation session
175  * @rcu_head: RCU head used for freeing this struct
176  * @reorder_lock: serializes access to reorder buffer, see below.
177  * @auto_seq: used for offloaded BA sessions to automatically pick head_seq_and
178  *	and ssn.
179  * @removed: this session is removed (but might have been found due to RCU)
180  *
181  * This structure's lifetime is managed by RCU, assignments to
182  * the array holding it must hold the aggregation mutex.
183  *
184  * The @reorder_lock is used to protect the members of this
185  * struct, except for @timeout, @buf_size and @dialog_token,
186  * which are constant across the lifetime of the struct (the
187  * dialog token being used only for debugging).
188  */
189 struct tid_ampdu_rx {
190 	struct rcu_head rcu_head;
191 	spinlock_t reorder_lock;
192 	struct sk_buff_head *reorder_buf;
193 	unsigned long *reorder_time;
194 	struct timer_list session_timer;
195 	struct timer_list reorder_timer;
196 	unsigned long last_rx;
197 	u16 head_seq_num;
198 	u16 stored_mpdu_num;
199 	u16 ssn;
200 	u16 buf_size;
201 	u16 timeout;
202 	u8 dialog_token;
203 	bool auto_seq;
204 	bool removed;
205 };
206 
207 /**
208  * struct sta_ampdu_mlme - STA aggregation information.
209  *
210  * @tid_rx: aggregation info for Rx per TID -- RCU protected
211  * @tid_tx: aggregation info for Tx per TID
212  * @tid_start_tx: sessions where start was requested
213  * @addba_req_num: number of times addBA request has been sent.
214  * @last_addba_req_time: timestamp of the last addBA request.
215  * @dialog_token_allocator: dialog token enumerator for each new session;
216  * @work: work struct for starting/stopping aggregation
217  * @tid_rx_timer_expired: bitmap indicating on which TIDs the
218  *	RX timer expired until the work for it runs
219  * @tid_rx_stop_requested:  bitmap indicating which BA sessions per TID the
220  *	driver requested to close until the work for it runs
221  * @mtx: mutex to protect all TX data (except non-NULL assignments
222  *	to tid_tx[idx], which are protected by the sta spinlock)
223  *	tid_start_tx is also protected by sta->lock.
224  */
225 struct sta_ampdu_mlme {
226 	struct mutex mtx;
227 	/* rx */
228 	struct tid_ampdu_rx __rcu *tid_rx[IEEE80211_NUM_TIDS];
229 	unsigned long tid_rx_timer_expired[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];
230 	unsigned long tid_rx_stop_requested[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];
231 	/* tx */
232 	struct work_struct work;
233 	struct tid_ampdu_tx __rcu *tid_tx[IEEE80211_NUM_TIDS];
234 	struct tid_ampdu_tx *tid_start_tx[IEEE80211_NUM_TIDS];
235 	unsigned long last_addba_req_time[IEEE80211_NUM_TIDS];
236 	u8 addba_req_num[IEEE80211_NUM_TIDS];
237 	u8 dialog_token_allocator;
238 };
239 
240 
241 /* Value to indicate no TID reservation */
242 #define IEEE80211_TID_UNRESERVED	0xff
243 
244 /**
245  * struct sta_info - STA information
246  *
247  * This structure collects information about a station that
248  * mac80211 is communicating with.
249  *
250  * @list: global linked list entry
251  * @free_list: list entry for keeping track of stations to free
252  * @hash_node: hash node for rhashtable
253  * @local: pointer to the global information
254  * @sdata: virtual interface this station belongs to
255  * @ptk: peer keys negotiated with this station, if any
256  * @ptk_idx: last installed peer key index
257  * @gtk: group keys negotiated with this station, if any
258  * @gtk_idx: last installed group key index
259  * @rate_ctrl: rate control algorithm reference
260  * @rate_ctrl_priv: rate control private per-STA pointer
261  * @last_tx_rate: rate used for last transmit, to report to userspace as
262  *	"the" transmit rate
263  * @last_rx_rate_idx: rx status rate index of the last data packet
264  * @last_rx_rate_flag: rx status flag of the last data packet
265  * @last_rx_rate_vht_flag: rx status vht flag of the last data packet
266  * @last_rx_rate_vht_nss: rx status nss of last data packet
267  * @lock: used for locking all fields that require locking, see comments
268  *	in the header file.
269  * @drv_deliver_wk: used for delivering frames after driver PS unblocking
270  * @listen_interval: listen interval of this station, when we're acting as AP
271  * @_flags: STA flags, see &enum ieee80211_sta_info_flags, do not use directly
272  * @ps_lock: used for powersave (when mac80211 is the AP) related locking
273  * @ps_tx_buf: buffers (per AC) of frames to transmit to this station
274  *	when it leaves power saving state or polls
275  * @tx_filtered: buffers (per AC) of frames we already tried to
276  *	transmit but were filtered by hardware due to STA having
277  *	entered power saving state, these are also delivered to
278  *	the station when it leaves powersave or polls for frames
279  * @driver_buffered_tids: bitmap of TIDs the driver has data buffered on
280  * @txq_buffered_tids: bitmap of TIDs that mac80211 has txq data buffered on
281  * @rx_packets: Number of MSDUs received from this STA
282  * @rx_bytes: Number of bytes received from this STA
283  * @last_rx: time (in jiffies) when last frame was received from this STA
284  * @last_connected: time (in seconds) when a station got connected
285  * @num_duplicates: number of duplicate frames received from this STA
286  * @rx_fragments: number of received MPDUs
287  * @rx_dropped: number of dropped MPDUs from this STA
288  * @last_signal: signal of last received frame from this STA
289  * @avg_signal: moving average of signal of received frames from this STA
290  * @last_ack_signal: signal of last received Ack frame from this STA
291  * @last_seq_ctrl: last received seq/frag number from this STA (per RX queue)
292  * @tx_filtered_count: number of frames the hardware filtered for this STA
293  * @tx_retry_failed: number of frames that failed retry
294  * @tx_retry_count: total number of retries for frames to this STA
295  * @fail_avg: moving percentage of failed MSDUs
296  * @tx_packets: number of RX/TX MSDUs
297  * @tx_bytes: number of bytes transmitted to this STA
298  * @tx_fragments: number of transmitted MPDUs
299  * @tid_seq: per-TID sequence numbers for sending to this STA
300  * @ampdu_mlme: A-MPDU state machine state
301  * @timer_to_tid: identity mapping to ID timers
302  * @llid: Local link ID
303  * @plid: Peer link ID
304  * @reason: Cancel reason on PLINK_HOLDING state
305  * @plink_retries: Retries in establishment
306  * @plink_state: peer link state
307  * @plink_timeout: timeout of peer link
308  * @plink_timer: peer link watch timer
309  * @t_offset: timing offset relative to this host
310  * @t_offset_setpoint: reference timing offset of this sta to be used when
311  * 	calculating clockdrift
312  * @local_pm: local link-specific power save mode
313  * @peer_pm: peer-specific power save mode towards local STA
314  * @nonpeer_pm: STA power save mode towards non-peer neighbors
315  * @debugfs: debug filesystem info
316  * @dead: set to true when sta is unlinked
317  * @uploaded: set to true when sta is uploaded to the driver
318  * @lost_packets: number of consecutive lost packets
319  * @sta: station information we share with the driver
320  * @sta_state: duplicates information about station state (for debug)
321  * @beacon_loss_count: number of times beacon loss has triggered
322  * @rcu_head: RCU head used for freeing this station struct
323  * @cur_max_bandwidth: maximum bandwidth to use for TX to the station,
324  *	taken from HT/VHT capabilities or VHT operating mode notification
325  * @chains: chains ever used for RX from this station
326  * @chain_signal_last: last signal (per chain)
327  * @chain_signal_avg: signal average (per chain)
328  * @known_smps_mode: the smps_mode the client thinks we are in. Relevant for
329  *	AP only.
330  * @cipher_scheme: optional cipher scheme for this station
331  * @last_tdls_pkt_time: holds the time in jiffies of last TDLS pkt ACKed
332  * @reserved_tid: reserved TID (if any, otherwise IEEE80211_TID_UNRESERVED)
333  * @tx_msdu: MSDUs transmitted to this station, using IEEE80211_NUM_TID
334  *	entry for non-QoS frames
335  * @tx_msdu_retries: MSDU retries for transmissions to to this station,
336  *	using IEEE80211_NUM_TID entry for non-QoS frames
337  * @tx_msdu_failed: MSDU failures for transmissions to to this station,
338  *	using IEEE80211_NUM_TID entry for non-QoS frames
339  * @rx_msdu: MSDUs received from this station, using IEEE80211_NUM_TID
340  *	entry for non-QoS frames
341  */
342 struct sta_info {
343 	/* General information, mostly static */
344 	struct list_head list, free_list;
345 	struct rcu_head rcu_head;
346 	struct rhash_head hash_node;
347 	struct ieee80211_local *local;
348 	struct ieee80211_sub_if_data *sdata;
349 	struct ieee80211_key __rcu *gtk[NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS];
350 	struct ieee80211_key __rcu *ptk[NUM_DEFAULT_KEYS];
351 	u8 gtk_idx;
352 	u8 ptk_idx;
353 	struct rate_control_ref *rate_ctrl;
354 	void *rate_ctrl_priv;
355 	spinlock_t lock;
356 
357 	struct work_struct drv_deliver_wk;
358 
359 	u16 listen_interval;
360 
361 	bool dead;
362 
363 	bool uploaded;
364 
365 	enum ieee80211_sta_state sta_state;
366 
367 	/* use the accessors defined below */
368 	unsigned long _flags;
369 
370 	/* STA powersave lock and frame queues */
371 	spinlock_t ps_lock;
372 	struct sk_buff_head ps_tx_buf[IEEE80211_NUM_ACS];
373 	struct sk_buff_head tx_filtered[IEEE80211_NUM_ACS];
374 	unsigned long driver_buffered_tids;
375 	unsigned long txq_buffered_tids;
376 
377 	/* Updated from RX path only, no locking requirements */
378 	unsigned long rx_packets;
379 	u64 rx_bytes;
380 	unsigned long last_rx;
381 	long last_connected;
382 	unsigned long num_duplicates;
383 	unsigned long rx_fragments;
384 	unsigned long rx_dropped;
385 	int last_signal;
386 	struct ewma avg_signal;
387 	int last_ack_signal;
388 
389 	u8 chains;
390 	s8 chain_signal_last[IEEE80211_MAX_CHAINS];
391 	struct ewma chain_signal_avg[IEEE80211_MAX_CHAINS];
392 
393 	/* Plus 1 for non-QoS frames */
394 	__le16 last_seq_ctrl[IEEE80211_NUM_TIDS + 1];
395 
396 	/* Updated from TX status path only, no locking requirements */
397 	unsigned long tx_filtered_count;
398 	unsigned long tx_retry_failed, tx_retry_count;
399 	/* moving percentage of failed MSDUs */
400 	unsigned int fail_avg;
401 
402 	/* Updated from TX path only, no locking requirements */
403 	u32 tx_fragments;
404 	u64 tx_packets[IEEE80211_NUM_ACS];
405 	u64 tx_bytes[IEEE80211_NUM_ACS];
406 	struct ieee80211_tx_rate last_tx_rate;
407 	int last_rx_rate_idx;
408 	u32 last_rx_rate_flag;
409 	u32 last_rx_rate_vht_flag;
410 	u8 last_rx_rate_vht_nss;
411 	u16 tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1];
412 	u64 tx_msdu[IEEE80211_NUM_TIDS + 1];
413 	u64 tx_msdu_retries[IEEE80211_NUM_TIDS + 1];
414 	u64 tx_msdu_failed[IEEE80211_NUM_TIDS + 1];
415 	u64 rx_msdu[IEEE80211_NUM_TIDS + 1];
416 
417 	/*
418 	 * Aggregation information, locked with lock.
419 	 */
420 	struct sta_ampdu_mlme ampdu_mlme;
421 	u8 timer_to_tid[IEEE80211_NUM_TIDS];
422 
423 #ifdef CONFIG_MAC80211_MESH
424 	/*
425 	 * Mesh peer link attributes
426 	 * TODO: move to a sub-structure that is referenced with pointer?
427 	 */
428 	u16 llid;
429 	u16 plid;
430 	u16 reason;
431 	u8 plink_retries;
432 	enum nl80211_plink_state plink_state;
433 	u32 plink_timeout;
434 	struct timer_list plink_timer;
435 	s64 t_offset;
436 	s64 t_offset_setpoint;
437 	/* mesh power save */
438 	enum nl80211_mesh_power_mode local_pm;
439 	enum nl80211_mesh_power_mode peer_pm;
440 	enum nl80211_mesh_power_mode nonpeer_pm;
441 #endif
442 
443 #ifdef CONFIG_MAC80211_DEBUGFS
444 	struct sta_info_debugfsdentries {
445 		struct dentry *dir;
446 		bool add_has_run;
447 	} debugfs;
448 #endif
449 
450 	enum ieee80211_sta_rx_bandwidth cur_max_bandwidth;
451 
452 	unsigned int lost_packets;
453 	unsigned int beacon_loss_count;
454 
455 	enum ieee80211_smps_mode known_smps_mode;
456 	const struct ieee80211_cipher_scheme *cipher_scheme;
457 
458 	/* TDLS timeout data */
459 	unsigned long last_tdls_pkt_time;
460 
461 	u8 reserved_tid;
462 
463 	/* keep last! */
464 	struct ieee80211_sta sta;
465 };
466 
467 static inline enum nl80211_plink_state sta_plink_state(struct sta_info *sta)
468 {
469 #ifdef CONFIG_MAC80211_MESH
470 	return sta->plink_state;
471 #endif
472 	return NL80211_PLINK_LISTEN;
473 }
474 
475 static inline void set_sta_flag(struct sta_info *sta,
476 				enum ieee80211_sta_info_flags flag)
477 {
478 	WARN_ON(flag == WLAN_STA_AUTH ||
479 		flag == WLAN_STA_ASSOC ||
480 		flag == WLAN_STA_AUTHORIZED);
481 	set_bit(flag, &sta->_flags);
482 }
483 
484 static inline void clear_sta_flag(struct sta_info *sta,
485 				  enum ieee80211_sta_info_flags flag)
486 {
487 	WARN_ON(flag == WLAN_STA_AUTH ||
488 		flag == WLAN_STA_ASSOC ||
489 		flag == WLAN_STA_AUTHORIZED);
490 	clear_bit(flag, &sta->_flags);
491 }
492 
493 static inline int test_sta_flag(struct sta_info *sta,
494 				enum ieee80211_sta_info_flags flag)
495 {
496 	return test_bit(flag, &sta->_flags);
497 }
498 
499 static inline int test_and_clear_sta_flag(struct sta_info *sta,
500 					  enum ieee80211_sta_info_flags flag)
501 {
502 	WARN_ON(flag == WLAN_STA_AUTH ||
503 		flag == WLAN_STA_ASSOC ||
504 		flag == WLAN_STA_AUTHORIZED);
505 	return test_and_clear_bit(flag, &sta->_flags);
506 }
507 
508 static inline int test_and_set_sta_flag(struct sta_info *sta,
509 					enum ieee80211_sta_info_flags flag)
510 {
511 	WARN_ON(flag == WLAN_STA_AUTH ||
512 		flag == WLAN_STA_ASSOC ||
513 		flag == WLAN_STA_AUTHORIZED);
514 	return test_and_set_bit(flag, &sta->_flags);
515 }
516 
517 int sta_info_move_state(struct sta_info *sta,
518 			enum ieee80211_sta_state new_state);
519 
520 static inline void sta_info_pre_move_state(struct sta_info *sta,
521 					   enum ieee80211_sta_state new_state)
522 {
523 	int ret;
524 
525 	WARN_ON_ONCE(test_sta_flag(sta, WLAN_STA_INSERTED));
526 
527 	ret = sta_info_move_state(sta, new_state);
528 	WARN_ON_ONCE(ret);
529 }
530 
531 
532 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
533 			     struct tid_ampdu_tx *tid_tx);
534 
535 static inline struct tid_ampdu_tx *
536 rcu_dereference_protected_tid_tx(struct sta_info *sta, int tid)
537 {
538 	return rcu_dereference_protected(sta->ampdu_mlme.tid_tx[tid],
539 					 lockdep_is_held(&sta->lock) ||
540 					 lockdep_is_held(&sta->ampdu_mlme.mtx));
541 }
542 
543 /* Maximum number of frames to buffer per power saving station per AC */
544 #define STA_MAX_TX_BUFFER	64
545 
546 /* Minimum buffered frame expiry time. If STA uses listen interval that is
547  * smaller than this value, the minimum value here is used instead. */
548 #define STA_TX_BUFFER_EXPIRE (10 * HZ)
549 
550 /* How often station data is cleaned up (e.g., expiration of buffered frames)
551  */
552 #define STA_INFO_CLEANUP_INTERVAL (10 * HZ)
553 
554 /*
555  * Get a STA info, must be under RCU read lock.
556  */
557 struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
558 			      const u8 *addr);
559 
560 struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
561 				  const u8 *addr);
562 
563 u32 sta_addr_hash(const void *key, u32 length, u32 seed);
564 
565 #define _sta_bucket_idx(_tbl, _a)					\
566 	rht_bucket_index(_tbl, sta_addr_hash(_a, ETH_ALEN, (_tbl)->hash_rnd))
567 
568 #define for_each_sta_info(local, tbl, _addr, _sta, _tmp)		\
569 	rht_for_each_entry_rcu(_sta, _tmp, tbl, 			\
570 			       _sta_bucket_idx(tbl, _addr),		\
571 			       hash_node)				\
572 	/* compare address and run code only if it matches */		\
573 	if (ether_addr_equal(_sta->sta.addr, (_addr)))
574 
575 /*
576  * Get STA info by index, BROKEN!
577  */
578 struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
579 				     int idx);
580 /*
581  * Create a new STA info, caller owns returned structure
582  * until sta_info_insert().
583  */
584 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
585 				const u8 *addr, gfp_t gfp);
586 
587 void sta_info_free(struct ieee80211_local *local, struct sta_info *sta);
588 
589 /*
590  * Insert STA info into hash table/list, returns zero or a
591  * -EEXIST if (if the same MAC address is already present).
592  *
593  * Calling the non-rcu version makes the caller relinquish,
594  * the _rcu version calls read_lock_rcu() and must be called
595  * without it held.
596  */
597 int sta_info_insert(struct sta_info *sta);
598 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU);
599 
600 int __must_check __sta_info_destroy(struct sta_info *sta);
601 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata,
602 			  const u8 *addr);
603 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
604 			      const u8 *addr);
605 
606 void sta_info_recalc_tim(struct sta_info *sta);
607 
608 int sta_info_init(struct ieee80211_local *local);
609 void sta_info_stop(struct ieee80211_local *local);
610 
611 /**
612  * sta_info_flush - flush matching STA entries from the STA table
613  *
614  * Returns the number of removed STA entries.
615  *
616  * @sdata: sdata to remove all stations from
617  * @vlans: if the given interface is an AP interface, also flush VLANs
618  */
619 int __sta_info_flush(struct ieee80211_sub_if_data *sdata, bool vlans);
620 
621 static inline int sta_info_flush(struct ieee80211_sub_if_data *sdata)
622 {
623 	return __sta_info_flush(sdata, false);
624 }
625 
626 void sta_set_rate_info_tx(struct sta_info *sta,
627 			  const struct ieee80211_tx_rate *rate,
628 			  struct rate_info *rinfo);
629 void sta_set_rate_info_rx(struct sta_info *sta,
630 			  struct rate_info *rinfo);
631 void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo);
632 
633 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
634 			  unsigned long exp_time);
635 u8 sta_info_tx_streams(struct sta_info *sta);
636 
637 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta);
638 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta);
639 void ieee80211_sta_ps_deliver_uapsd(struct sta_info *sta);
640 
641 #endif /* STA_INFO_H */
642