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authorJohannes Berg <johannes@sipsolutions.net>2008-05-15 12:55:29 +0200
committerJohn W. Linville <linville@tuxdriver.com>2008-05-21 21:48:11 -0400
commite039fa4a4195ac4ee895e6f3d1334beed63256fe (patch)
treecfd0762d73df96b73052378be7b157c4ac6e7035 /include/net/mac80211.h
parente24549485f859be6518929bb1c9c0257d79f033d (diff)
mac80211: move TX info into skb->cb
This patch converts mac80211 and all drivers to have transmit information and status in skb->cb rather than allocating extra memory for it and copying all the data around. To make it fit, a union is used where only data that is necessary for all steps is kept outside of the union. A number of fixes were done by Ivo, as well as the rt2x00 part of this patch. Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'include/net/mac80211.h')
-rw-r--r--include/net/mac80211.h299
1 files changed, 133 insertions, 166 deletions
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 0df91bea6c1..54960b83db7 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -201,101 +201,127 @@ struct ieee80211_bss_conf {
};
/**
- * enum mac80211_tx_control_flags - flags to describe Tx configuration for
- * the Tx frame
- *
- * These flags are used with the @flags member of &ieee80211_tx_control
- *
- * @IEEE80211_TXCTL_REQ_TX_STATUS: request TX status callback for this frame.
- * @IEEE80211_TXCTL_DO_NOT_ENCRYPT: send this frame without encryption;
- * e.g., for EAPOL frame
- * @IEEE80211_TXCTL_USE_RTS_CTS: use RTS-CTS before sending frame
- * @IEEE80211_TXCTL_USE_CTS_PROTECT: use CTS protection for the frame (e.g.,
- * for combined 802.11g / 802.11b networks)
- * @IEEE80211_TXCTL_NO_ACK: tell the low level not to wait for an ack
- * @IEEE80211_TXCTL_RATE_CTRL_PROBE
- * @EEE80211_TXCTL_CLEAR_PS_FILT: clear powersave filter
- * for destination station
- * @IEEE80211_TXCTL_REQUEUE:
- * @IEEE80211_TXCTL_FIRST_FRAGMENT: this is a first fragment of the frame
- * @IEEE80211_TXCTL_LONG_RETRY_LIMIT: this frame should be send using the
- * through set_retry_limit configured long
- * retry value
- * @IEEE80211_TXCTL_EAPOL_FRAME: internal to mac80211
- * @IEEE80211_TXCTL_SEND_AFTER_DTIM: send this frame after DTIM beacon
- * @IEEE80211_TXCTL_AMPDU: this frame should be sent as part of an A-MPDU
- * @IEEE80211_TXCTL_OFDM_HT: this frame can be sent in HT OFDM rates. number
- * of streams when this flag is on can be extracted
- * from antenna_sel_tx, so if 1 antenna is marked
- * use SISO, 2 antennas marked use MIMO, n antennas
- * marked use MIMO_n.
- * @IEEE80211_TXCTL_GREEN_FIELD: use green field protection for this frame
- * @IEEE80211_TXCTL_40_MHZ_WIDTH: send this frame using 40 Mhz channel width
- * @IEEE80211_TXCTL_DUP_DATA: duplicate data frame on both 20 Mhz channels
- * @IEEE80211_TXCTL_SHORT_GI: send this frame using short guard interval
+ * enum mac80211_tx_flags - flags to transmission information/status
+ *
+ * These flags are used with the @flags member of &ieee80211_tx_info
+ *
+ * @IEEE80211_TX_CTL_REQ_TX_STATUS: request TX status callback for this frame.
+ * @IEEE80211_TX_CTL_DO_NOT_ENCRYPT: send this frame without encryption;
+ * e.g., for EAPOL frame
+ * @IEEE80211_TX_CTL_USE_RTS_CTS: use RTS-CTS before sending frame
+ * @IEEE80211_TX_CTL_USE_CTS_PROTECT: use CTS protection for the frame (e.g.,
+ * for combined 802.11g / 802.11b networks)
+ * @IEEE80211_TX_CTL_NO_ACK: tell the low level not to wait for an ack
+ * @IEEE80211_TX_CTL_RATE_CTRL_PROBE
+ * @IEEE80211_TX_CTL_CLEAR_PS_FILT: clear powersave filter for destination
+ * station
+ * @IEEE80211_TX_CTL_REQUEUE:
+ * @IEEE80211_TX_CTL_FIRST_FRAGMENT: this is a first fragment of the frame
+ * @IEEE80211_TX_CTL_LONG_RETRY_LIMIT: this frame should be send using the
+ * through set_retry_limit configured long retry value
+ * @IEEE80211_TX_CTL_EAPOL_FRAME: internal to mac80211
+ * @IEEE80211_TX_CTL_SEND_AFTER_DTIM: send this frame after DTIM beacon
+ * @IEEE80211_TX_CTL_AMPDU: this frame should be sent as part of an A-MPDU
+ * @IEEE80211_TX_CTL_OFDM_HT: this frame can be sent in HT OFDM rates. number
+ * of streams when this flag is on can be extracted from antenna_sel_tx,
+ * so if 1 antenna is marked use SISO, 2 antennas marked use MIMO, n
+ * antennas marked use MIMO_n.
+ * @IEEE80211_TX_CTL_GREEN_FIELD: use green field protection for this frame
+ * @IEEE80211_TX_CTL_40_MHZ_WIDTH: send this frame using 40 Mhz channel width
+ * @IEEE80211_TX_CTL_DUP_DATA: duplicate data frame on both 20 Mhz channels
+ * @IEEE80211_TX_CTL_SHORT_GI: send this frame using short guard interval
+ * @IEEE80211_TX_STAT_TX_FILTERED: The frame was not transmitted
+ * because the destination STA was in powersave mode.
+ * @IEEE80211_TX_STAT_ACK: Frame was acknowledged
+ * @IEEE80211_TX_STAT_AMPDU: The frame was aggregated, so status
+ * is for the whole aggregation.
*/
enum mac80211_tx_control_flags {
- IEEE80211_TXCTL_REQ_TX_STATUS = (1<<0),
- IEEE80211_TXCTL_DO_NOT_ENCRYPT = (1<<1),
- IEEE80211_TXCTL_USE_RTS_CTS = (1<<2),
- IEEE80211_TXCTL_USE_CTS_PROTECT = (1<<3),
- IEEE80211_TXCTL_NO_ACK = (1<<4),
- IEEE80211_TXCTL_RATE_CTRL_PROBE = (1<<5),
- IEEE80211_TXCTL_CLEAR_PS_FILT = (1<<6),
- IEEE80211_TXCTL_REQUEUE = (1<<7),
- IEEE80211_TXCTL_FIRST_FRAGMENT = (1<<8),
- IEEE80211_TXCTL_SHORT_PREAMBLE = (1<<9),
- IEEE80211_TXCTL_LONG_RETRY_LIMIT = (1<<10),
- IEEE80211_TXCTL_EAPOL_FRAME = (1<<11),
- IEEE80211_TXCTL_SEND_AFTER_DTIM = (1<<12),
- IEEE80211_TXCTL_AMPDU = (1<<13),
- IEEE80211_TXCTL_OFDM_HT = (1<<14),
- IEEE80211_TXCTL_GREEN_FIELD = (1<<15),
- IEEE80211_TXCTL_40_MHZ_WIDTH = (1<<16),
- IEEE80211_TXCTL_DUP_DATA = (1<<17),
- IEEE80211_TXCTL_SHORT_GI = (1<<18),
+ IEEE80211_TX_CTL_REQ_TX_STATUS = BIT(0),
+ IEEE80211_TX_CTL_DO_NOT_ENCRYPT = BIT(1),
+ IEEE80211_TX_CTL_USE_RTS_CTS = BIT(2),
+ IEEE80211_TX_CTL_USE_CTS_PROTECT = BIT(3),
+ IEEE80211_TX_CTL_NO_ACK = BIT(4),
+ IEEE80211_TX_CTL_RATE_CTRL_PROBE = BIT(5),
+ IEEE80211_TX_CTL_CLEAR_PS_FILT = BIT(6),
+ IEEE80211_TX_CTL_REQUEUE = BIT(7),
+ IEEE80211_TX_CTL_FIRST_FRAGMENT = BIT(8),
+ IEEE80211_TX_CTL_SHORT_PREAMBLE = BIT(9),
+ IEEE80211_TX_CTL_LONG_RETRY_LIMIT = BIT(10),
+ IEEE80211_TX_CTL_EAPOL_FRAME = BIT(11),
+ IEEE80211_TX_CTL_SEND_AFTER_DTIM = BIT(12),
+ IEEE80211_TX_CTL_AMPDU = BIT(13),
+ IEEE80211_TX_CTL_OFDM_HT = BIT(14),
+ IEEE80211_TX_CTL_GREEN_FIELD = BIT(15),
+ IEEE80211_TX_CTL_40_MHZ_WIDTH = BIT(16),
+ IEEE80211_TX_CTL_DUP_DATA = BIT(17),
+ IEEE80211_TX_CTL_SHORT_GI = BIT(18),
+ IEEE80211_TX_CTL_INJECTED = BIT(19),
+ IEEE80211_TX_STAT_TX_FILTERED = BIT(20),
+ IEEE80211_TX_STAT_ACK = BIT(21),
+ IEEE80211_TX_STAT_AMPDU = BIT(22),
};
-/* Transmit control fields. This data structure is passed to low-level driver
- * with each TX frame. The low-level driver is responsible for configuring
- * the hardware to use given values (depending on what is supported).
- *
- * NOTE: Be careful with using the pointers outside of the ieee80211_ops->tx()
- * context (i.e. when defering the work to a workqueue).
- * The vif pointer is valid until the it has been removed with the
- * ieee80211_ops->remove_interface() callback funtion.
- * The hw_key pointer is valid until it has been removed with the
- * ieee80211_ops->set_key() callback function.
- */
-struct ieee80211_tx_control {
- u32 flags; /* tx control flags defined above */
-
- s8 tx_rate_idx, /* Transmit rate (indexes registered rates) */
- rts_cts_rate_idx, /* Transmit rate for RTS/CTS frame */
- alt_retry_rate_idx; /* retry rate for the last retries */
-
- s8 retry_limit; /* 1 = only first attempt, 2 = one retry, ..
- * This could be used when set_retry_limit
- * is not implemented by the driver */
- struct ieee80211_vif *vif;
-
- /* Key used for hardware encryption
- * NULL if IEEE80211_TXCTL_DO_NOT_ENCRYPT is set */
- struct ieee80211_key_conf *hw_key;
+#define IEEE80211_TX_INFO_DRIVER_DATA_SIZE \
+ (sizeof(((struct sk_buff *)0)->cb) - 8)
+#define IEEE80211_TX_INFO_DRIVER_DATA_PTRS \
+ (IEEE80211_TX_INFO_DRIVER_DATA_SIZE / sizeof(void *))
- enum ieee80211_band band;
+/**
+ * struct ieee80211_tx_info - skb transmit information
+ *
+ * This structure is placed in skb->cb for three uses:
+ * (1) mac80211 TX control - mac80211 tells the driver what to do
+ * (2) driver internal use (if applicable)
+ * (3) TX status information - driver tells mac80211 what happened
+ *
+ * @flags: transmit info flags, defined above
+ * @retry_count: number of retries
+ * @excessive_retries: set to 1 if the frame was retried many times
+ * but not acknowledged
+ * @ampdu_ack_len: number of aggregated frames.
+ * relevant only if IEEE80211_TX_STATUS_AMPDU was set.
+ * @ampdu_ack_map: block ack bit map for the aggregation.
+ * relevant only if IEEE80211_TX_STATUS_AMPDU was set.
+ * @ack_signal: signal strength of the ACK frame
+ */
+struct ieee80211_tx_info {
+ /* common information */
+ u32 flags;
+ u8 band;
+ s8 tx_rate_idx;
+ u8 antenna_sel_tx;
- u8 antenna_sel_tx; /* 0 = default/diversity, otherwise bit
- * position represents antenna number used */
- u8 icv_len; /* length of the ICV/MIC field in octets */
- u8 iv_len; /* length of the IV field in octets */
- u16 queue; /* hardware queue to use for this frame;
- * 0 = highest, hw->queues-1 = lowest */
- u16 aid; /* Station AID */
- int type; /* internal */
+ u8 queue; /* use skb_queue_mapping soon */
+
+ union {
+ struct {
+ struct ieee80211_vif *vif;
+ struct ieee80211_key_conf *hw_key;
+ unsigned long jiffies;
+ int ifindex;
+ u16 aid;
+ s8 rts_cts_rate_idx, alt_retry_rate_idx;
+ u8 retry_limit;
+ u8 icv_len;
+ u8 iv_len;
+ } control;
+ struct {
+ u64 ampdu_ack_map;
+ int ack_signal;
+ u8 retry_count;
+ bool excessive_retries;
+ u8 ampdu_ack_len;
+ } status;
+ void *driver_data[IEEE80211_TX_INFO_DRIVER_DATA_PTRS];
+ };
};
+static inline struct ieee80211_tx_info *IEEE80211_SKB_CB(struct sk_buff *skb)
+{
+ return (struct ieee80211_tx_info *)skb->cb;
+}
/**
@@ -363,52 +389,6 @@ struct ieee80211_rx_status {
};
/**
- * enum ieee80211_tx_status_flags - transmit status flags
- *
- * Status flags to indicate various transmit conditions.
- *
- * @IEEE80211_TX_STATUS_TX_FILTERED: The frame was not transmitted
- * because the destination STA was in powersave mode.
- * @IEEE80211_TX_STATUS_ACK: Frame was acknowledged
- * @IEEE80211_TX_STATUS_AMPDU: The frame was aggregated, so status
- * is for the whole aggregation.
- */
-enum ieee80211_tx_status_flags {
- IEEE80211_TX_STATUS_TX_FILTERED = 1<<0,
- IEEE80211_TX_STATUS_ACK = 1<<1,
- IEEE80211_TX_STATUS_AMPDU = 1<<2,
-};
-
-/**
- * struct ieee80211_tx_status - transmit status
- *
- * As much information as possible should be provided for each transmitted
- * frame with ieee80211_tx_status().
- *
- * @control: a copy of the &struct ieee80211_tx_control passed to the driver
- * in the tx() callback.
- * @flags: transmit status flags, defined above
- * @retry_count: number of retries
- * @excessive_retries: set to 1 if the frame was retried many times
- * but not acknowledged
- * @ampdu_ack_len: number of aggregated frames.
- * relevant only if IEEE80211_TX_STATUS_AMPDU was set.
- * @ampdu_ack_map: block ack bit map for the aggregation.
- * relevant only if IEEE80211_TX_STATUS_AMPDU was set.
- * @ack_signal: signal strength of the ACK frame either in dBm, dB or unspec
- * depending on hardware capabilites flags @IEEE80211_HW_SIGNAL_*
- */
-struct ieee80211_tx_status {
- struct ieee80211_tx_control control;
- u8 flags;
- u8 retry_count;
- bool excessive_retries;
- u8 ampdu_ack_len;
- u64 ampdu_ack_map;
- int ack_signal;
-};
-
-/**
* enum ieee80211_conf_flags - configuration flags
*
* Flags to define PHY configuration options
@@ -563,7 +543,6 @@ struct ieee80211_if_conf {
u8 *ssid;
size_t ssid_len;
struct sk_buff *beacon;
- struct ieee80211_tx_control *beacon_control;
};
/**
@@ -825,7 +804,7 @@ static inline void SET_IEEE80211_PERM_ADDR(struct ieee80211_hw *hw, u8 *addr)
static inline struct ieee80211_rate *
ieee80211_get_tx_rate(const struct ieee80211_hw *hw,
- const struct ieee80211_tx_control *c)
+ const struct ieee80211_tx_info *c)
{
if (WARN_ON(c->tx_rate_idx < 0))
return NULL;
@@ -834,20 +813,20 @@ ieee80211_get_tx_rate(const struct ieee80211_hw *hw,
static inline struct ieee80211_rate *
ieee80211_get_rts_cts_rate(const struct ieee80211_hw *hw,
- const struct ieee80211_tx_control *c)
+ const struct ieee80211_tx_info *c)
{
- if (c->rts_cts_rate_idx < 0)
+ if (c->control.rts_cts_rate_idx < 0)
return NULL;
- return &hw->wiphy->bands[c->band]->bitrates[c->rts_cts_rate_idx];
+ return &hw->wiphy->bands[c->band]->bitrates[c->control.rts_cts_rate_idx];
}
static inline struct ieee80211_rate *
ieee80211_get_alt_retry_rate(const struct ieee80211_hw *hw,
- const struct ieee80211_tx_control *c)
+ const struct ieee80211_tx_info *c)
{
- if (c->alt_retry_rate_idx < 0)
+ if (c->control.alt_retry_rate_idx < 0)
return NULL;
- return &hw->wiphy->bands[c->band]->bitrates[c->alt_retry_rate_idx];
+ return &hw->wiphy->bands[c->band]->bitrates[c->control.alt_retry_rate_idx];
}
/**
@@ -1142,8 +1121,7 @@ enum ieee80211_ampdu_mlme_action {
* that TX/RX_STOP can pass NULL for this parameter.
*/
struct ieee80211_ops {
- int (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb,
- struct ieee80211_tx_control *control);
+ int (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb);
int (*start)(struct ieee80211_hw *hw);
void (*stop)(struct ieee80211_hw *hw);
int (*add_interface)(struct ieee80211_hw *hw,
@@ -1187,8 +1165,7 @@ struct ieee80211_ops {
u64 (*get_tsf)(struct ieee80211_hw *hw);
void (*reset_tsf)(struct ieee80211_hw *hw);
int (*beacon_update)(struct ieee80211_hw *hw,
- struct sk_buff *skb,
- struct ieee80211_tx_control *control);
+ struct sk_buff *skb);
int (*tx_last_beacon)(struct ieee80211_hw *hw);
int (*ampdu_action)(struct ieee80211_hw *hw,
enum ieee80211_ampdu_mlme_action action,
@@ -1384,13 +1361,9 @@ void ieee80211_rx_irqsafe(struct ieee80211_hw *hw,
*
* @hw: the hardware the frame was transmitted by
* @skb: the frame that was transmitted, owned by mac80211 after this call
- * @status: status information for this frame; the status pointer need not
- * be valid after this function returns and is not freed by mac80211,
- * it is recommended that it points to a stack area
*/
void ieee80211_tx_status(struct ieee80211_hw *hw,
- struct sk_buff *skb,
- struct ieee80211_tx_status *status);
+ struct sk_buff *skb);
/**
* ieee80211_tx_status_irqsafe - irq-safe transmit status callback
@@ -1403,13 +1376,9 @@ void ieee80211_tx_status(struct ieee80211_hw *hw,
*
* @hw: the hardware the frame was transmitted by
* @skb: the frame that was transmitted, owned by mac80211 after this call
- * @status: status information for this frame; the status pointer need not
- * be valid after this function returns and is not freed by mac80211,
- * it is recommended that it points to a stack area
*/
void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
- struct sk_buff *skb,
- struct ieee80211_tx_status *status);
+ struct sk_buff *skb);
/**
* ieee80211_beacon_get - beacon generation function
@@ -1425,8 +1394,7 @@ void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
* is responsible of freeing it.
*/
struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
- struct ieee80211_vif *vif,
- struct ieee80211_tx_control *control);
+ struct ieee80211_vif *vif);
/**
* ieee80211_rts_get - RTS frame generation function
@@ -1434,7 +1402,7 @@ struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
* @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
* @frame: pointer to the frame that is going to be protected by the RTS.
* @frame_len: the frame length (in octets).
- * @frame_txctl: &struct ieee80211_tx_control of the frame.
+ * @frame_txctl: &struct ieee80211_tx_info of the frame.
* @rts: The buffer where to store the RTS frame.
*
* If the RTS frames are generated by the host system (i.e., not in
@@ -1444,7 +1412,7 @@ struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
*/
void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
const void *frame, size_t frame_len,
- const struct ieee80211_tx_control *frame_txctl,
+ const struct ieee80211_tx_info *frame_txctl,
struct ieee80211_rts *rts);
/**
@@ -1452,7 +1420,7 @@ void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
* @hw: pointer obtained from ieee80211_alloc_hw().
* @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
* @frame_len: the length of the frame that is going to be protected by the RTS.
- * @frame_txctl: &struct ieee80211_tx_control of the frame.
+ * @frame_txctl: &struct ieee80211_tx_info of the frame.
*
* If the RTS is generated in firmware, but the host system must provide
* the duration field, the low-level driver uses this function to receive
@@ -1460,7 +1428,7 @@ void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
*/
__le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
struct ieee80211_vif *vif, size_t frame_len,
- const struct ieee80211_tx_control *frame_txctl);
+ const struct ieee80211_tx_info *frame_txctl);
/**
* ieee80211_ctstoself_get - CTS-to-self frame generation function
@@ -1468,7 +1436,7 @@ __le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
* @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
* @frame: pointer to the frame that is going to be protected by the CTS-to-self.
* @frame_len: the frame length (in octets).
- * @frame_txctl: &struct ieee80211_tx_control of the frame.
+ * @frame_txctl: &struct ieee80211_tx_info of the frame.
* @cts: The buffer where to store the CTS-to-self frame.
*
* If the CTS-to-self frames are generated by the host system (i.e., not in
@@ -1479,7 +1447,7 @@ __le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
void ieee80211_ctstoself_get(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
const void *frame, size_t frame_len,
- const struct ieee80211_tx_control *frame_txctl,
+ const struct ieee80211_tx_info *frame_txctl,
struct ieee80211_cts *cts);
/**
@@ -1487,7 +1455,7 @@ void ieee80211_ctstoself_get(struct ieee80211_hw *hw,
* @hw: pointer obtained from ieee80211_alloc_hw().
* @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
* @frame_len: the length of the frame that is going to be protected by the CTS-to-self.
- * @frame_txctl: &struct ieee80211_tx_control of the frame.
+ * @frame_txctl: &struct ieee80211_tx_info of the frame.
*
* If the CTS-to-self is generated in firmware, but the host system must provide
* the duration field, the low-level driver uses this function to receive
@@ -1496,7 +1464,7 @@ void ieee80211_ctstoself_get(struct ieee80211_hw *hw,
__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
size_t frame_len,
- const struct ieee80211_tx_control *frame_txctl);
+ const struct ieee80211_tx_info *frame_txctl);
/**
* ieee80211_generic_frame_duration - Calculate the duration field for a frame
@@ -1535,8 +1503,7 @@ __le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw,
* use common code for all beacons.
*/
struct sk_buff *
-ieee80211_get_buffered_bc(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
- struct ieee80211_tx_control *control);
+ieee80211_get_buffered_bc(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
/**
* ieee80211_get_hdrlen_from_skb - get header length from data