xref: /linux/net/mac80211/sta_info.h (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
1 /*
2  * Copyright 2002-2005, Devicescape Software, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #ifndef STA_INFO_H
10 #define STA_INFO_H
11 
12 #include <linux/list.h>
13 #include <linux/types.h>
14 #include <linux/if_ether.h>
15 #include <linux/workqueue.h>
16 #include "key.h"
17 
18 /**
19  * enum ieee80211_sta_info_flags - Stations flags
20  *
21  * These flags are used with &struct sta_info's @flags member.
22  *
23  * @WLAN_STA_AUTH: Station is authenticated.
24  * @WLAN_STA_ASSOC: Station is associated.
25  * @WLAN_STA_PS_STA: Station is in power-save mode
26  * @WLAN_STA_AUTHORIZED: Station is authorized to send/receive traffic.
27  *	This bit is always checked so needs to be enabled for all stations
28  *	when virtual port control is not in use.
29  * @WLAN_STA_SHORT_PREAMBLE: Station is capable of receiving short-preamble
30  *	frames.
31  * @WLAN_STA_ASSOC_AP: We're associated to that station, it is an AP.
32  * @WLAN_STA_WME: Station is a QoS-STA.
33  * @WLAN_STA_WDS: Station is one of our WDS peers.
34  * @WLAN_STA_CLEAR_PS_FILT: Clear PS filter in hardware (using the
35  *	IEEE80211_TX_CTL_CLEAR_PS_FILT control flag) when the next
36  *	frame to this station is transmitted.
37  * @WLAN_STA_MFP: Management frame protection is used with this STA.
38  * @WLAN_STA_BLOCK_BA: Used to deny ADDBA requests (both TX and RX)
39  *	during suspend/resume and station removal.
40  * @WLAN_STA_PS_DRIVER: driver requires keeping this station in
41  *	power-save mode logically to flush frames that might still
42  *	be in the queues
43  * @WLAN_STA_PSPOLL: Station sent PS-poll while driver was keeping
44  *	station in power-save mode, reply when the driver unblocks.
45  */
46 enum ieee80211_sta_info_flags {
47 	WLAN_STA_AUTH		= 1<<0,
48 	WLAN_STA_ASSOC		= 1<<1,
49 	WLAN_STA_PS_STA		= 1<<2,
50 	WLAN_STA_AUTHORIZED	= 1<<3,
51 	WLAN_STA_SHORT_PREAMBLE	= 1<<4,
52 	WLAN_STA_ASSOC_AP	= 1<<5,
53 	WLAN_STA_WME		= 1<<6,
54 	WLAN_STA_WDS		= 1<<7,
55 	WLAN_STA_CLEAR_PS_FILT	= 1<<9,
56 	WLAN_STA_MFP		= 1<<10,
57 	WLAN_STA_BLOCK_BA	= 1<<11,
58 	WLAN_STA_PS_DRIVER	= 1<<12,
59 	WLAN_STA_PSPOLL		= 1<<13,
60 };
61 
62 #define STA_TID_NUM 16
63 #define ADDBA_RESP_INTERVAL HZ
64 #define HT_AGG_MAX_RETRIES		0x3
65 
66 #define HT_AGG_STATE_DRV_READY		0
67 #define HT_AGG_STATE_RESPONSE_RECEIVED	1
68 #define HT_AGG_STATE_OPERATIONAL	2
69 #define HT_AGG_STATE_STOPPING		3
70 #define HT_AGG_STATE_WANT_START		4
71 #define HT_AGG_STATE_WANT_STOP		5
72 
73 /**
74  * struct tid_ampdu_tx - TID aggregation information (Tx).
75  *
76  * @rcu_head: rcu head for freeing structure
77  * @addba_resp_timer: timer for peer's response to addba request
78  * @pending: pending frames queue -- use sta's spinlock to protect
79  * @dialog_token: dialog token for aggregation session
80  * @state: session state (see above)
81  * @stop_initiator: initiator of a session stop
82  *
83  * This structure is protected by RCU and the per-station
84  * spinlock. Assignments to the array holding it must hold
85  * the spinlock, only the TX path can access it under RCU
86  * lock-free if, and only if, the state has  the flag
87  * %HT_AGG_STATE_OPERATIONAL set. Otherwise, the TX path
88  * must also acquire the spinlock and re-check the state,
89  * see comments in the tx code touching it.
90  */
91 struct tid_ampdu_tx {
92 	struct rcu_head rcu_head;
93 	struct timer_list addba_resp_timer;
94 	struct sk_buff_head pending;
95 	unsigned long state;
96 	u8 dialog_token;
97 	u8 stop_initiator;
98 };
99 
100 /**
101  * struct tid_ampdu_rx - TID aggregation information (Rx).
102  *
103  * @reorder_buf: buffer to reorder incoming aggregated MPDUs
104  * @reorder_time: jiffies when skb was added
105  * @session_timer: check if peer keeps Tx-ing on the TID (by timeout value)
106  * @head_seq_num: head sequence number in reordering buffer.
107  * @stored_mpdu_num: number of MPDUs in reordering buffer
108  * @ssn: Starting Sequence Number expected to be aggregated.
109  * @buf_size: buffer size for incoming A-MPDUs
110  * @timeout: reset timer value (in TUs).
111  * @dialog_token: dialog token for aggregation session
112  * @rcu_head: RCU head used for freeing this struct
113  *
114  * This structure is protected by RCU and the per-station
115  * spinlock. Assignments to the array holding it must hold
116  * the spinlock, only the RX path can access it under RCU
117  * lock-free. The RX path, since it is single-threaded,
118  * can even modify the structure without locking since the
119  * only other modifications to it are done when the struct
120  * can not yet or no longer be found by the RX path.
121  */
122 struct tid_ampdu_rx {
123 	struct rcu_head rcu_head;
124 	struct sk_buff **reorder_buf;
125 	unsigned long *reorder_time;
126 	struct timer_list session_timer;
127 	u16 head_seq_num;
128 	u16 stored_mpdu_num;
129 	u16 ssn;
130 	u16 buf_size;
131 	u16 timeout;
132 	u8 dialog_token;
133 };
134 
135 /**
136  * struct sta_ampdu_mlme - STA aggregation information.
137  *
138  * @tid_rx: aggregation info for Rx per TID -- RCU protected
139  * @tid_tx: aggregation info for Tx per TID
140  * @addba_req_num: number of times addBA request has been sent.
141  * @dialog_token_allocator: dialog token enumerator for each new session;
142  * @work: work struct for starting/stopping aggregation
143  * @tid_rx_timer_expired: bitmap indicating on which TIDs the
144  *	RX timer expired until the work for it runs
145  * @mtx: mutex to protect all TX data (except non-NULL assignments
146  *	to tid_tx[idx], which are protected by the sta spinlock)
147  */
148 struct sta_ampdu_mlme {
149 	struct mutex mtx;
150 	/* rx */
151 	struct tid_ampdu_rx *tid_rx[STA_TID_NUM];
152 	unsigned long tid_rx_timer_expired[BITS_TO_LONGS(STA_TID_NUM)];
153 	/* tx */
154 	struct work_struct work;
155 	struct tid_ampdu_tx *tid_tx[STA_TID_NUM];
156 	u8 addba_req_num[STA_TID_NUM];
157 	u8 dialog_token_allocator;
158 };
159 
160 
161 /**
162  * enum plink_state - state of a mesh peer link finite state machine
163  *
164  * @PLINK_LISTEN: initial state, considered the implicit state of non existant
165  * 	mesh peer links
166  * @PLINK_OPN_SNT: mesh plink open frame has been sent to this mesh peer
167  * @PLINK_OPN_RCVD: mesh plink open frame has been received from this mesh peer
168  * @PLINK_CNF_RCVD: mesh plink confirm frame has been received from this mesh
169  * 	peer
170  * @PLINK_ESTAB: mesh peer link is established
171  * @PLINK_HOLDING: mesh peer link is being closed or cancelled
172  * @PLINK_BLOCKED: all frames transmitted from this mesh plink are discarded
173  */
174 enum plink_state {
175 	PLINK_LISTEN,
176 	PLINK_OPN_SNT,
177 	PLINK_OPN_RCVD,
178 	PLINK_CNF_RCVD,
179 	PLINK_ESTAB,
180 	PLINK_HOLDING,
181 	PLINK_BLOCKED
182 };
183 
184 /**
185  * struct sta_info - STA information
186  *
187  * This structure collects information about a station that
188  * mac80211 is communicating with.
189  *
190  * @list: global linked list entry
191  * @hnext: hash table linked list pointer
192  * @local: pointer to the global information
193  * @sdata: virtual interface this station belongs to
194  * @key: peer key negotiated with this station, if any
195  * @rate_ctrl: rate control algorithm reference
196  * @rate_ctrl_priv: rate control private per-STA pointer
197  * @last_tx_rate: rate used for last transmit, to report to userspace as
198  *	"the" transmit rate
199  * @lock: used for locking all fields that require locking, see comments
200  *	in the header file.
201  * @flaglock: spinlock for flags accesses
202  * @drv_unblock_wk: used for driver PS unblocking
203  * @listen_interval: listen interval of this station, when we're acting as AP
204  * @flags: STA flags, see &enum ieee80211_sta_info_flags
205  * @ps_tx_buf: buffer of frames to transmit to this station
206  *	when it leaves power saving state
207  * @tx_filtered: buffer of frames we already tried to transmit
208  *	but were filtered by hardware due to STA having entered
209  *	power saving state
210  * @rx_packets: Number of MSDUs received from this STA
211  * @rx_bytes: Number of bytes received from this STA
212  * @wep_weak_iv_count: number of weak WEP IVs received from this station
213  * @last_rx: time (in jiffies) when last frame was received from this STA
214  * @num_duplicates: number of duplicate frames received from this STA
215  * @rx_fragments: number of received MPDUs
216  * @rx_dropped: number of dropped MPDUs from this STA
217  * @last_signal: signal of last received frame from this STA
218  * @last_seq_ctrl: last received seq/frag number from this STA (per RX queue)
219  * @tx_filtered_count: number of frames the hardware filtered for this STA
220  * @tx_retry_failed: number of frames that failed retry
221  * @tx_retry_count: total number of retries for frames to this STA
222  * @fail_avg: moving percentage of failed MSDUs
223  * @tx_packets: number of RX/TX MSDUs
224  * @tx_bytes: number of bytes transmitted to this STA
225  * @tx_fragments: number of transmitted MPDUs
226  * @tid_seq: per-TID sequence numbers for sending to this STA
227  * @ampdu_mlme: A-MPDU state machine state
228  * @timer_to_tid: identity mapping to ID timers
229  * @llid: Local link ID
230  * @plid: Peer link ID
231  * @reason: Cancel reason on PLINK_HOLDING state
232  * @plink_retries: Retries in establishment
233  * @ignore_plink_timer: ignore the peer-link timer (used internally)
234  * @plink_state: peer link state
235  * @plink_timeout: timeout of peer link
236  * @plink_timer: peer link watch timer
237  * @plink_timer_was_running: used by suspend/resume to restore timers
238  * @debugfs: debug filesystem info
239  * @sta: station information we share with the driver
240  * @dead: set to true when sta is unlinked
241  * @uploaded: set to true when sta is uploaded to the driver
242  */
243 struct sta_info {
244 	/* General information, mostly static */
245 	struct list_head list;
246 	struct sta_info *hnext;
247 	struct ieee80211_local *local;
248 	struct ieee80211_sub_if_data *sdata;
249 	struct ieee80211_key *key;
250 	struct rate_control_ref *rate_ctrl;
251 	void *rate_ctrl_priv;
252 	spinlock_t lock;
253 	spinlock_t flaglock;
254 
255 	struct work_struct drv_unblock_wk;
256 
257 	u16 listen_interval;
258 
259 	bool dead;
260 
261 	bool uploaded;
262 
263 	/*
264 	 * frequently updated, locked with own spinlock (flaglock),
265 	 * use the accessors defined below
266 	 */
267 	u32 flags;
268 
269 	/*
270 	 * STA powersave frame queues, no more than the internal
271 	 * locking required.
272 	 */
273 	struct sk_buff_head ps_tx_buf;
274 	struct sk_buff_head tx_filtered;
275 
276 	/* Updated from RX path only, no locking requirements */
277 	unsigned long rx_packets, rx_bytes;
278 	unsigned long wep_weak_iv_count;
279 	unsigned long last_rx;
280 	unsigned long num_duplicates;
281 	unsigned long rx_fragments;
282 	unsigned long rx_dropped;
283 	int last_signal;
284 	__le16 last_seq_ctrl[NUM_RX_DATA_QUEUES];
285 
286 	/* Updated from TX status path only, no locking requirements */
287 	unsigned long tx_filtered_count;
288 	unsigned long tx_retry_failed, tx_retry_count;
289 	/* moving percentage of failed MSDUs */
290 	unsigned int fail_avg;
291 
292 	/* Updated from TX path only, no locking requirements */
293 	unsigned long tx_packets;
294 	unsigned long tx_bytes;
295 	unsigned long tx_fragments;
296 	struct ieee80211_tx_rate last_tx_rate;
297 	u16 tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1];
298 
299 	/*
300 	 * Aggregation information, locked with lock.
301 	 */
302 	struct sta_ampdu_mlme ampdu_mlme;
303 	u8 timer_to_tid[STA_TID_NUM];
304 
305 #ifdef CONFIG_MAC80211_MESH
306 	/*
307 	 * Mesh peer link attributes
308 	 * TODO: move to a sub-structure that is referenced with pointer?
309 	 */
310 	__le16 llid;
311 	__le16 plid;
312 	__le16 reason;
313 	u8 plink_retries;
314 	bool ignore_plink_timer;
315 	bool plink_timer_was_running;
316 	enum plink_state plink_state;
317 	u32 plink_timeout;
318 	struct timer_list plink_timer;
319 #endif
320 
321 #ifdef CONFIG_MAC80211_DEBUGFS
322 	struct sta_info_debugfsdentries {
323 		struct dentry *dir;
324 		bool add_has_run;
325 	} debugfs;
326 #endif
327 
328 	/* keep last! */
329 	struct ieee80211_sta sta;
330 };
331 
332 static inline enum plink_state sta_plink_state(struct sta_info *sta)
333 {
334 #ifdef CONFIG_MAC80211_MESH
335 	return sta->plink_state;
336 #endif
337 	return PLINK_LISTEN;
338 }
339 
340 static inline void set_sta_flags(struct sta_info *sta, const u32 flags)
341 {
342 	unsigned long irqfl;
343 
344 	spin_lock_irqsave(&sta->flaglock, irqfl);
345 	sta->flags |= flags;
346 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
347 }
348 
349 static inline void clear_sta_flags(struct sta_info *sta, const u32 flags)
350 {
351 	unsigned long irqfl;
352 
353 	spin_lock_irqsave(&sta->flaglock, irqfl);
354 	sta->flags &= ~flags;
355 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
356 }
357 
358 static inline u32 test_sta_flags(struct sta_info *sta, const u32 flags)
359 {
360 	u32 ret;
361 	unsigned long irqfl;
362 
363 	spin_lock_irqsave(&sta->flaglock, irqfl);
364 	ret = sta->flags & flags;
365 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
366 
367 	return ret;
368 }
369 
370 static inline u32 test_and_clear_sta_flags(struct sta_info *sta,
371 					   const u32 flags)
372 {
373 	u32 ret;
374 	unsigned long irqfl;
375 
376 	spin_lock_irqsave(&sta->flaglock, irqfl);
377 	ret = sta->flags & flags;
378 	sta->flags &= ~flags;
379 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
380 
381 	return ret;
382 }
383 
384 static inline u32 get_sta_flags(struct sta_info *sta)
385 {
386 	u32 ret;
387 	unsigned long irqfl;
388 
389 	spin_lock_irqsave(&sta->flaglock, irqfl);
390 	ret = sta->flags;
391 	spin_unlock_irqrestore(&sta->flaglock, irqfl);
392 
393 	return ret;
394 }
395 
396 
397 
398 #define STA_HASH_SIZE 256
399 #define STA_HASH(sta) (sta[5])
400 
401 
402 /* Maximum number of frames to buffer per power saving station */
403 #define STA_MAX_TX_BUFFER 128
404 
405 /* Minimum buffered frame expiry time. If STA uses listen interval that is
406  * smaller than this value, the minimum value here is used instead. */
407 #define STA_TX_BUFFER_EXPIRE (10 * HZ)
408 
409 /* How often station data is cleaned up (e.g., expiration of buffered frames)
410  */
411 #define STA_INFO_CLEANUP_INTERVAL (10 * HZ)
412 
413 /*
414  * Get a STA info, must be under RCU read lock.
415  */
416 struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
417 			      const u8 *addr);
418 
419 struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
420 				  const u8 *addr);
421 
422 static inline
423 void for_each_sta_info_type_check(struct ieee80211_local *local,
424 				  const u8 *addr,
425 				  struct sta_info *sta,
426 				  struct sta_info *nxt)
427 {
428 }
429 
430 #define for_each_sta_info(local, _addr, _sta, nxt) 			\
431 	for (	/* initialise loop */					\
432 		_sta = rcu_dereference(local->sta_hash[STA_HASH(_addr)]),\
433 		nxt = _sta ? rcu_dereference(_sta->hnext) : NULL;	\
434 		/* typecheck */						\
435 		for_each_sta_info_type_check(local, (_addr), _sta, nxt),\
436 		/* continue condition */				\
437 		_sta;							\
438 		/* advance loop */					\
439 		_sta = nxt,						\
440 		nxt = _sta ? rcu_dereference(_sta->hnext) : NULL	\
441 	     )								\
442 	/* compare address and run code only if it matches */		\
443 	if (memcmp(_sta->sta.addr, (_addr), ETH_ALEN) == 0)
444 
445 /*
446  * Get STA info by index, BROKEN!
447  */
448 struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
449 				     int idx);
450 /*
451  * Create a new STA info, caller owns returned structure
452  * until sta_info_insert().
453  */
454 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
455 				u8 *addr, gfp_t gfp);
456 /*
457  * Insert STA info into hash table/list, returns zero or a
458  * -EEXIST if (if the same MAC address is already present).
459  *
460  * Calling the non-rcu version makes the caller relinquish,
461  * the _rcu version calls read_lock_rcu() and must be called
462  * without it held.
463  */
464 int sta_info_insert(struct sta_info *sta);
465 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU);
466 int sta_info_insert_atomic(struct sta_info *sta);
467 
468 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata,
469 			  const u8 *addr);
470 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
471 			      const u8 *addr);
472 
473 void sta_info_set_tim_bit(struct sta_info *sta);
474 void sta_info_clear_tim_bit(struct sta_info *sta);
475 
476 void sta_info_init(struct ieee80211_local *local);
477 int sta_info_start(struct ieee80211_local *local);
478 void sta_info_stop(struct ieee80211_local *local);
479 int sta_info_flush(struct ieee80211_local *local,
480 		   struct ieee80211_sub_if_data *sdata);
481 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
482 			  unsigned long exp_time);
483 
484 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta);
485 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta);
486 
487 #endif /* STA_INFO_H */
488