linux/net/mac80211/sta_info.h
Johannes Berg 63044e9f54 mac80211: fix debugfs lockup
When debugfs_create_dir fails, sta_info_debugfs_add_work will not
terminate because it will find the same station again and again.
This is possible whenever debugfs fails for whatever reason; one
reason is a race condition in mac80211, unfortunately we cannot
do much about it, so just document it, it just means some station
may be missing from debugfs.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-10-14 20:46:41 -04:00

449 lines
13 KiB
C

/*
* Copyright 2002-2005, Devicescape Software, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef STA_INFO_H
#define STA_INFO_H
#include <linux/list.h>
#include <linux/types.h>
#include <linux/if_ether.h>
#include "key.h"
/**
* enum ieee80211_sta_info_flags - Stations flags
*
* These flags are used with &struct sta_info's @flags member.
*
* @WLAN_STA_AUTH: Station is authenticated.
* @WLAN_STA_ASSOC: Station is associated.
* @WLAN_STA_PS: Station is in power-save mode
* @WLAN_STA_AUTHORIZED: Station is authorized to send/receive traffic.
* This bit is always checked so needs to be enabled for all stations
* when virtual port control is not in use.
* @WLAN_STA_SHORT_PREAMBLE: Station is capable of receiving short-preamble
* frames.
* @WLAN_STA_ASSOC_AP: We're associated to that station, it is an AP.
* @WLAN_STA_WME: Station is a QoS-STA.
* @WLAN_STA_WDS: Station is one of our WDS peers.
* @WLAN_STA_PSPOLL: Station has just PS-polled us.
* @WLAN_STA_CLEAR_PS_FILT: Clear PS filter in hardware (using the
* IEEE80211_TX_CTL_CLEAR_PS_FILT control flag) when the next
* frame to this station is transmitted.
*/
enum ieee80211_sta_info_flags {
WLAN_STA_AUTH = 1<<0,
WLAN_STA_ASSOC = 1<<1,
WLAN_STA_PS = 1<<2,
WLAN_STA_AUTHORIZED = 1<<3,
WLAN_STA_SHORT_PREAMBLE = 1<<4,
WLAN_STA_ASSOC_AP = 1<<5,
WLAN_STA_WME = 1<<6,
WLAN_STA_WDS = 1<<7,
WLAN_STA_PSPOLL = 1<<8,
WLAN_STA_CLEAR_PS_FILT = 1<<9,
};
#define STA_TID_NUM 16
#define ADDBA_RESP_INTERVAL HZ
#define HT_AGG_MAX_RETRIES (0x3)
#define HT_AGG_STATE_INITIATOR_SHIFT (4)
#define HT_ADDBA_REQUESTED_MSK BIT(0)
#define HT_ADDBA_DRV_READY_MSK BIT(1)
#define HT_ADDBA_RECEIVED_MSK BIT(2)
#define HT_AGG_STATE_REQ_STOP_BA_MSK BIT(3)
#define HT_AGG_STATE_INITIATOR_MSK BIT(HT_AGG_STATE_INITIATOR_SHIFT)
#define HT_AGG_STATE_IDLE (0x0)
#define HT_AGG_STATE_OPERATIONAL (HT_ADDBA_REQUESTED_MSK | \
HT_ADDBA_DRV_READY_MSK | \
HT_ADDBA_RECEIVED_MSK)
#define HT_AGG_STATE_DEBUGFS_CTL BIT(7)
/**
* struct tid_ampdu_tx - TID aggregation information (Tx).
*
* @addba_resp_timer: timer for peer's response to addba request
* @ssn: Starting Sequence Number expected to be aggregated.
* @dialog_token: dialog token for aggregation session
*/
struct tid_ampdu_tx {
struct timer_list addba_resp_timer;
u16 ssn;
u8 dialog_token;
};
/**
* struct tid_ampdu_rx - TID aggregation information (Rx).
*
* @reorder_buf: buffer to reorder incoming aggregated MPDUs
* @session_timer: check if peer keeps Tx-ing on the TID (by timeout value)
* @head_seq_num: head sequence number in reordering buffer.
* @stored_mpdu_num: number of MPDUs in reordering buffer
* @ssn: Starting Sequence Number expected to be aggregated.
* @buf_size: buffer size for incoming A-MPDUs
* @timeout: reset timer value.
* @dialog_token: dialog token for aggregation session
*/
struct tid_ampdu_rx {
struct sk_buff **reorder_buf;
struct timer_list session_timer;
u16 head_seq_num;
u16 stored_mpdu_num;
u16 ssn;
u16 buf_size;
u16 timeout;
u8 dialog_token;
};
/**
* enum plink_state - state of a mesh peer link finite state machine
*
* @PLINK_LISTEN: initial state, considered the implicit state of non existant
* mesh peer links
* @PLINK_OPN_SNT: mesh plink open frame has been sent to this mesh peer
* @PLINK_OPN_RCVD: mesh plink open frame has been received from this mesh peer
* @PLINK_CNF_RCVD: mesh plink confirm frame has been received from this mesh
* peer
* @PLINK_ESTAB: mesh peer link is established
* @PLINK_HOLDING: mesh peer link is being closed or cancelled
* @PLINK_BLOCKED: all frames transmitted from this mesh plink are discarded
*/
enum plink_state {
PLINK_LISTEN,
PLINK_OPN_SNT,
PLINK_OPN_RCVD,
PLINK_CNF_RCVD,
PLINK_ESTAB,
PLINK_HOLDING,
PLINK_BLOCKED
};
/**
* struct sta_ampdu_mlme - STA aggregation information.
*
* @tid_state_rx: TID's state in Rx session state machine.
* @tid_rx: aggregation info for Rx per TID
* @tid_state_tx: TID's state in Tx session state machine.
* @tid_tx: aggregation info for Tx per TID
* @addba_req_num: number of times addBA request has been sent.
* @dialog_token_allocator: dialog token enumerator for each new session;
*/
struct sta_ampdu_mlme {
/* rx */
u8 tid_state_rx[STA_TID_NUM];
struct tid_ampdu_rx *tid_rx[STA_TID_NUM];
/* tx */
u8 tid_state_tx[STA_TID_NUM];
struct tid_ampdu_tx *tid_tx[STA_TID_NUM];
u8 addba_req_num[STA_TID_NUM];
u8 dialog_token_allocator;
};
/* see __sta_info_unlink */
#define STA_INFO_PIN_STAT_NORMAL 0
#define STA_INFO_PIN_STAT_PINNED 1
#define STA_INFO_PIN_STAT_DESTROY 2
/**
* struct sta_info - STA information
*
* This structure collects information about a station that
* mac80211 is communicating with.
*
* @list: global linked list entry
* @hnext: hash table linked list pointer
* @local: pointer to the global information
* @sdata: TBD
* @key: TBD
* @rate_ctrl: TBD
* @rate_ctrl_priv: TBD
* @lock: used for locking all fields that require locking, see comments
* in the header file.
* @flaglock: spinlock for flags accesses
* @addr: MAC address of this STA
* @aid: STA's unique AID (1..2007, 0 = not assigned yet),
* only used in AP (and IBSS?) mode
* @listen_interval: TBD
* @pin_status: TBD
* @flags: STA flags, see &enum ieee80211_sta_info_flags
* @ps_tx_buf: buffer of frames to transmit to this station
* when it leaves power saving state
* @tx_filtered: buffer of frames we already tried to transmit
* but were filtered by hardware due to STA having entered
* power saving state
* @rx_packets: Number of MSDUs received from this STA
* @rx_bytes: Number of bytes received from this STA
* @wep_weak_iv_count: TBD
* @last_rx: TBD
* @num_duplicates: number of duplicate frames received from this STA
* @rx_fragments: number of received MPDUs
* @rx_dropped: number of dropped MPDUs from this STA
* @last_signal: signal of last received frame from this STA
* @last_qual: qual of last received frame from this STA
* @last_noise: noise of last received frame from this STA
* @last_seq_ctrl: last received seq/frag number from this STA (per RX queue)
* @tx_filtered_count: TBD
* @tx_retry_failed: TBD
* @tx_retry_count: TBD
* @fail_avg: moving percentage of failed MSDUs
* @tx_packets: number of RX/TX MSDUs
* @tx_bytes: TBD
* @tx_fragments: number of transmitted MPDUs
* @last_txrate_idx: Index of the last used transmit rate
* @tid_seq: TBD
* @ampdu_mlme: TBD
* @timer_to_tid: identity mapping to ID timers
* @tid_to_tx_q: map tid to tx queue
* @llid: Local link ID
* @plid: Peer link ID
* @reason: Cancel reason on PLINK_HOLDING state
* @plink_retries: Retries in establishment
* @ignore_plink_timer: TBD
* @plink_state plink_state: TBD
* @plink_timeout: TBD
* @plink_timer: TBD
* @debugfs: debug filesystem info
* @sta: station information we share with the driver
*/
struct sta_info {
/* General information, mostly static */
struct list_head list;
struct sta_info *hnext;
struct ieee80211_local *local;
struct ieee80211_sub_if_data *sdata;
struct ieee80211_key *key;
struct rate_control_ref *rate_ctrl;
void *rate_ctrl_priv;
spinlock_t lock;
spinlock_t flaglock;
u16 listen_interval;
/*
* for use by the internal lifetime management,
* see __sta_info_unlink
*/
u8 pin_status;
/*
* frequently updated, locked with own spinlock (flaglock),
* use the accessors defined below
*/
u32 flags;
/*
* STA powersave frame queues, no more than the internal
* locking required.
*/
struct sk_buff_head ps_tx_buf;
struct sk_buff_head tx_filtered;
/* Updated from RX path only, no locking requirements */
unsigned long rx_packets, rx_bytes;
unsigned long wep_weak_iv_count;
unsigned long last_rx;
unsigned long num_duplicates;
unsigned long rx_fragments;
unsigned long rx_dropped;
int last_signal;
int last_qual;
int last_noise;
__le16 last_seq_ctrl[NUM_RX_DATA_QUEUES];
/* Updated from TX status path only, no locking requirements */
unsigned long tx_filtered_count;
unsigned long tx_retry_failed, tx_retry_count;
/* moving percentage of failed MSDUs */
unsigned int fail_avg;
/* Updated from TX path only, no locking requirements */
unsigned long tx_packets;
unsigned long tx_bytes;
unsigned long tx_fragments;
unsigned int last_txrate_idx;
u16 tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1];
/*
* Aggregation information, locked with lock.
*/
struct sta_ampdu_mlme ampdu_mlme;
u8 timer_to_tid[STA_TID_NUM];
u8 tid_to_tx_q[STA_TID_NUM];
#ifdef CONFIG_MAC80211_MESH
/*
* Mesh peer link attributes
* TODO: move to a sub-structure that is referenced with pointer?
*/
__le16 llid;
__le16 plid;
__le16 reason;
u8 plink_retries;
bool ignore_plink_timer;
enum plink_state plink_state;
u32 plink_timeout;
struct timer_list plink_timer;
#endif
#ifdef CONFIG_MAC80211_DEBUGFS
struct sta_info_debugfsdentries {
struct dentry *dir;
struct dentry *flags;
struct dentry *num_ps_buf_frames;
struct dentry *inactive_ms;
struct dentry *last_seq_ctrl;
struct dentry *agg_status;
bool add_has_run;
} debugfs;
#endif
/* keep last! */
struct ieee80211_sta sta;
};
static inline enum plink_state sta_plink_state(struct sta_info *sta)
{
#ifdef CONFIG_MAC80211_MESH
return sta->plink_state;
#endif
return PLINK_LISTEN;
}
static inline void set_sta_flags(struct sta_info *sta, const u32 flags)
{
unsigned long irqfl;
spin_lock_irqsave(&sta->flaglock, irqfl);
sta->flags |= flags;
spin_unlock_irqrestore(&sta->flaglock, irqfl);
}
static inline void clear_sta_flags(struct sta_info *sta, const u32 flags)
{
unsigned long irqfl;
spin_lock_irqsave(&sta->flaglock, irqfl);
sta->flags &= ~flags;
spin_unlock_irqrestore(&sta->flaglock, irqfl);
}
static inline void set_and_clear_sta_flags(struct sta_info *sta,
const u32 set, const u32 clear)
{
unsigned long irqfl;
spin_lock_irqsave(&sta->flaglock, irqfl);
sta->flags |= set;
sta->flags &= ~clear;
spin_unlock_irqrestore(&sta->flaglock, irqfl);
}
static inline u32 test_sta_flags(struct sta_info *sta, const u32 flags)
{
u32 ret;
unsigned long irqfl;
spin_lock_irqsave(&sta->flaglock, irqfl);
ret = sta->flags & flags;
spin_unlock_irqrestore(&sta->flaglock, irqfl);
return ret;
}
static inline u32 test_and_clear_sta_flags(struct sta_info *sta,
const u32 flags)
{
u32 ret;
unsigned long irqfl;
spin_lock_irqsave(&sta->flaglock, irqfl);
ret = sta->flags & flags;
sta->flags &= ~flags;
spin_unlock_irqrestore(&sta->flaglock, irqfl);
return ret;
}
static inline u32 get_sta_flags(struct sta_info *sta)
{
u32 ret;
unsigned long irqfl;
spin_lock_irqsave(&sta->flaglock, irqfl);
ret = sta->flags;
spin_unlock_irqrestore(&sta->flaglock, irqfl);
return ret;
}
/* Maximum number of concurrently registered stations */
#define MAX_STA_COUNT 2007
#define STA_HASH_SIZE 256
#define STA_HASH(sta) (sta[5])
/* Maximum number of frames to buffer per power saving station */
#define STA_MAX_TX_BUFFER 128
/* Minimum buffered frame expiry time. If STA uses listen interval that is
* smaller than this value, the minimum value here is used instead. */
#define STA_TX_BUFFER_EXPIRE (10 * HZ)
/* How often station data is cleaned up (e.g., expiration of buffered frames)
*/
#define STA_INFO_CLEANUP_INTERVAL (10 * HZ)
/*
* Get a STA info, must have be under RCU read lock.
*/
struct sta_info *sta_info_get(struct ieee80211_local *local, const u8 *addr);
/*
* Get STA info by index, BROKEN!
*/
struct sta_info *sta_info_get_by_idx(struct ieee80211_local *local, int idx,
struct net_device *dev);
/*
* Create a new STA info, caller owns returned structure
* until sta_info_insert().
*/
struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
u8 *addr, gfp_t gfp);
/*
* Insert STA info into hash table/list, returns zero or a
* -EEXIST if (if the same MAC address is already present).
*
* Calling this without RCU protection makes the caller
* relinquish its reference to @sta.
*/
int sta_info_insert(struct sta_info *sta);
/*
* Unlink a STA info from the hash table/list.
* This can NULL the STA pointer if somebody else
* has already unlinked it.
*/
void sta_info_unlink(struct sta_info **sta);
void sta_info_destroy(struct sta_info *sta);
void sta_info_set_tim_bit(struct sta_info *sta);
void sta_info_clear_tim_bit(struct sta_info *sta);
void sta_info_init(struct ieee80211_local *local);
int sta_info_start(struct ieee80211_local *local);
void sta_info_stop(struct ieee80211_local *local);
int sta_info_flush(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata);
void sta_info_flush_delayed(struct ieee80211_sub_if_data *sdata);
void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
unsigned long exp_time);
#endif /* STA_INFO_H */