mac80211: remove probe response temporary buffer allocation

Instead of allocating a temporary buffer to build IEs
build them right into the SKB.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/mac80211_hwsim.c

@@ -1347,9 +1347,14 @@ static void hw_scan_work(struct work_struct *work)
 						       hwsim->hw_scan_vif,
 						       req->ssids[i].ssid,
 						       req->ssids[i].ssid_len,
-						       req->ie, req->ie_len);
+						       req->ie_len);
 			if (!probe)
 				continue;
+
+			if (req->ie_len)
+				memcpy(skb_put(probe, req->ie_len), req->ie,
+				       req->ie_len);
+
 			local_bh_disable();
 			mac80211_hwsim_tx_frame(hwsim->hw, probe,
 						hwsim->tmp_chan);

drivers/net/wireless/ti/wl1251/main.c

@@ -896,11 +896,13 @@ static int wl1251_op_hw_scan(struct ieee80211_hw *hw,
 		goto out;
 
 	skb = ieee80211_probereq_get(wl->hw, wl->vif, ssid, ssid_len,
-				     req->ie, req->ie_len);
+				     req->ie_len);
 	if (!skb) {
 		ret = -ENOMEM;
 		goto out;
 	}
+	if (req->ie_len)
+		memcpy(skb_put(skb, req->ie_len), req->ie, req->ie_len);
 
 	ret = wl1251_cmd_template_set(wl, CMD_PROBE_REQ, skb->data,
 				      skb->len);

drivers/net/wireless/ti/wlcore/cmd.c

@@ -1038,11 +1038,13 @@ int wl12xx_cmd_build_probe_req(struct wl1271 *wl, struct wl12xx_vif *wlvif,
 	u16 template_id_5 = CMD_TEMPL_CFG_PROBE_REQ_5;
 
 	skb = ieee80211_probereq_get(wl->hw, vif, ssid, ssid_len,
-				     ie, ie_len);
+				     ie_len);
 	if (!skb) {
 		ret = -ENOMEM;
 		goto out;
 	}
+	if (ie_len)
+		memcpy(skb_put(skb, ie_len), ie, ie_len);
 
 	wl1271_dump(DEBUG_SCAN, "PROBE REQ: ", skb->data, skb->len);
 

include/net/mac80211.h

@@ -3144,8 +3144,7 @@ struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
  * @vif: &struct ieee80211_vif pointer from the add_interface callback.
  * @ssid: SSID buffer
  * @ssid_len: length of SSID
- * @ie: buffer containing all IEs except SSID for the template
+ * @tailroom: tailroom to reserve at end of SKB for IEs
- * @ie_len: length of the IE buffer
  *
  * Creates a Probe Request template which can, for example, be uploaded to
  * hardware.
@@ -3153,7 +3152,7 @@ struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
 				       struct ieee80211_vif *vif,
 				       const u8 *ssid, size_t ssid_len,
-				       const u8 *ie, size_t ie_len);
+				       size_t tailroom);
 
 /**
  * ieee80211_rts_get - RTS frame generation function

net/mac80211/tx.c

@@ -2620,7 +2620,7 @@ EXPORT_SYMBOL(ieee80211_nullfunc_get);
 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
 				       struct ieee80211_vif *vif,
 				       const u8 *ssid, size_t ssid_len,
-				       const u8 *ie, size_t ie_len)
+				       size_t tailroom)
 {
 	struct ieee80211_sub_if_data *sdata;
 	struct ieee80211_local *local;
@@ -2634,7 +2634,7 @@ struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
 	ie_ssid_len = 2 + ssid_len;
 
 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
-			    ie_ssid_len + ie_len);
+			    ie_ssid_len + tailroom);
 	if (!skb)
 		return NULL;
 
@@ -2655,11 +2655,6 @@ struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
 		memcpy(pos, ssid, ssid_len);
 	pos += ssid_len;
 
-	if (ie) {
-		pos = skb_put(skb, ie_len);
-		memcpy(pos, ie, ie_len);
-	}
-
 	return skb;
 }
 EXPORT_SYMBOL(ieee80211_probereq_get);

net/mac80211/util.c

@@ -1239,14 +1239,8 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_local *local = sdata->local;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
-	size_t buf_len;
-	u8 *buf;
 	u8 chan_no;
-
+	int ies_len;
-	/* FIXME: come up with a proper value */
-	buf = kmalloc(200 + ie_len, GFP_KERNEL);
-	if (!buf)
-		return NULL;
 
 	/*
 	 * Do not send DS Channel parameter for directed probe requests
@@ -1258,15 +1252,16 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 	else
 		chan_no = ieee80211_frequency_to_channel(chan->center_freq);
 
-	buf_len = ieee80211_build_preq_ies(local, buf, 200 + ie_len,
+	skb = ieee80211_probereq_get(&local->hw, &sdata->vif,
+				     ssid, ssid_len, 100 + ie_len);
+	if (!skb)
+		return NULL;
+
+	ies_len = ieee80211_build_preq_ies(local, skb_tail_pointer(skb),
+					   skb_tailroom(skb),
 					   ie, ie_len, chan->band,
 					   ratemask, chan_no);
-
+	skb_put(skb, ies_len);
-	skb = ieee80211_probereq_get(&local->hw, &sdata->vif,
-				     ssid, ssid_len,
-				     buf, buf_len);
-	if (!skb)
-		goto out;
 
 	if (dst) {
 		mgmt = (struct ieee80211_mgmt *) skb->data;
@@ -1276,9 +1271,6 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 
 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
 
- out:
-	kfree(buf);
-
 	return skb;
 }