[PATCH next] drivers: wireless: ar5523: use container_of
From: Florian Westphal <fw@strlen.de>
Date: 2015-03-10 14:25:47
Also in:
linux-wireless
Subsystem:
atheros ath generic utilities, the rest, usb ar5523 wireless driver · Maintainers:
Jeff Johnson, Linus Torvalds
If we want to shrink skb->cb then we'd have to see about reducing struct ieee80211_tx_info, which gets embedded inside skb->cb[]. It provides a scratch space to be used by wireless drivers. ar5523 uses the maximum space available today (40 bytes), but it seems we don't need this -- data->skb pointer seems to always point back to the skb whose cb buffer the data structure resides, iow, given a pointer to the embedded control buffer we can infer the skb address. Tested-by: Pontus Fuchs <redacted> Signed-off-by: Florian Westphal <fw@strlen.de> --- drivers/net/wireless/ath/ar5523/ar5523.c | 9 +++++---- drivers/net/wireless/ath/ar5523/ar5523.h | 1 - 2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/net/wireless/ath/ar5523/ar5523.c b/drivers/net/wireless/ath/ar5523/ar5523.c
index f920506..5147ebe 100644
--- a/drivers/net/wireless/ath/ar5523/ar5523.c
+++ b/drivers/net/wireless/ath/ar5523/ar5523.c@@ -779,8 +779,6 @@ static void ar5523_tx(struct ieee80211_hw *hw, ieee80211_stop_queues(hw); } - data->skb = skb; - spin_lock_irqsave(&ar->tx_data_list_lock, flags); list_add_tail(&data->list, &ar->tx_queue_pending); spin_unlock_irqrestore(&ar->tx_data_list_lock, flags);
@@ -817,10 +815,13 @@ static void ar5523_tx_work_locked(struct ar5523 *ar) if (!data) break; - skb = data->skb; + txi = container_of((void *)data, struct ieee80211_tx_info, + driver_data); txqid = 0; - txi = IEEE80211_SKB_CB(skb); + + skb = container_of((void *)txi, struct sk_buff, cb); paylen = skb->len; + urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) { ar5523_err(ar, "Failed to allocate TX urb\n");
diff --git a/drivers/net/wireless/ath/ar5523/ar5523.h b/drivers/net/wireless/ath/ar5523/ar5523.h
index 00c6fd3..9a322a6 100644
--- a/drivers/net/wireless/ath/ar5523/ar5523.h
+++ b/drivers/net/wireless/ath/ar5523/ar5523.h@@ -74,7 +74,6 @@ struct ar5523_tx_cmd { struct ar5523_tx_data { struct list_head list; struct ar5523 *ar; - struct sk_buff *skb; struct urb *urb; };
--
2.0.5