iwmc3200wifi: Avoid an offset calculation for each management frame.

Determine the offset at compile time.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/iwmc3200wifi/rx.c b/drivers/net/wireless/iwmc3200wifi/rx.c
index 6bd253a..0619d6a 100644 (file)
--- a/drivers/net/wireless/iwmc3200wifi/rx.c
+++ b/drivers/net/wireless/iwmc3200wifi/rx.c
@@ -868,36 +868,35 @@ static int iwm_mlme_mgt_frame(struct iwm_priv *iwm, u8 *buf,
        struct iwm_umac_notif_mgt_frame *mgt_frame =
                        (struct iwm_umac_notif_mgt_frame *)buf;
        struct ieee80211_mgmt *mgt = (struct ieee80211_mgmt *)mgt_frame->frame;
-       u8 *ie;
 
        IWM_HEXDUMP(iwm, DBG, MLME, "MGT: ", mgt_frame->frame,
                    le16_to_cpu(mgt_frame->len));
 
        if (ieee80211_is_assoc_req(mgt->frame_control)) {
-               ie = mgt->u.assoc_req.variable;;
-               iwm->req_ie_len =
-                               le16_to_cpu(mgt_frame->len) - (ie - (u8 *)mgt);
+               iwm->req_ie_len = le16_to_cpu(mgt_frame->len)
+                                 - offsetof(struct ieee80211_mgmt,
+                                            u.assoc_req.variable);
                kfree(iwm->req_ie);
                iwm->req_ie = kmemdup(mgt->u.assoc_req.variable,
                                      iwm->req_ie_len, GFP_KERNEL);
        } else if (ieee80211_is_reassoc_req(mgt->frame_control)) {
-               ie = mgt->u.reassoc_req.variable;;
-               iwm->req_ie_len =
-                               le16_to_cpu(mgt_frame->len) - (ie - (u8 *)mgt);
+               iwm->req_ie_len = le16_to_cpu(mgt_frame->len)
+                                 - offsetof(struct ieee80211_mgmt,
+                                            u.reassoc_req.variable);
                kfree(iwm->req_ie);
                iwm->req_ie = kmemdup(mgt->u.reassoc_req.variable,
                                      iwm->req_ie_len, GFP_KERNEL);
        } else if (ieee80211_is_assoc_resp(mgt->frame_control)) {
-               ie = mgt->u.assoc_resp.variable;;
-               iwm->resp_ie_len =
-                               le16_to_cpu(mgt_frame->len) - (ie - (u8 *)mgt);
+               iwm->resp_ie_len = le16_to_cpu(mgt_frame->len)
+                                  - offsetof(struct ieee80211_mgmt,
+                                             u.assoc_resp.variable);
                kfree(iwm->resp_ie);
                iwm->resp_ie = kmemdup(mgt->u.assoc_resp.variable,
                                       iwm->resp_ie_len, GFP_KERNEL);
        } else if (ieee80211_is_reassoc_resp(mgt->frame_control)) {
-               ie = mgt->u.reassoc_resp.variable;;
-               iwm->resp_ie_len =
-                               le16_to_cpu(mgt_frame->len) - (ie - (u8 *)mgt);
+               iwm->resp_ie_len = le16_to_cpu(mgt_frame->len)
+                                  - offsetof(struct ieee80211_mgmt,
+                                             u.reassoc_resp.variable);
                kfree(iwm->resp_ie);
                iwm->resp_ie = kmemdup(mgt->u.reassoc_resp.variable,
                                       iwm->resp_ie_len, GFP_KERNEL);