mac80211: comment allocation of mesh frames

Remove most references to magic numbers, save a few bytes and hopefully
improve readability.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 18 insertions, 18 deletions

diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 174040a4288..9a1f8bbc49b 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -113,20 +113,20 @@ static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
                 struct ieee80211_sub_if_data *sdata)
 {
         struct ieee80211_local *local = sdata->local;
-        struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
+        struct sk_buff *skb;
         struct ieee80211_mgmt *mgmt;
-        u8 *pos;
-        int ie_len;
+        u8 *pos, ie_len;
+        int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
+                      sizeof(mgmt->u.action.u.mesh_action);
 
+        skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+                            hdr_len +
+                            2 + 37); /* max HWMP IE */
         if (!skb)
                 return -1;
         skb_reserve(skb, local->hw.extra_tx_headroom);
-        /* 25 is the size of the common mgmt part (24) plus the size of the
-         * common action part (1)
-         */
-        mgmt = (struct ieee80211_mgmt *)
-                skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
-        memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
+        mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
+        memset(mgmt, 0, hdr_len);
         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
                                           IEEE80211_STYPE_ACTION);
 
@@ -240,20 +240,20 @@ int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn,
                        struct ieee80211_sub_if_data *sdata)
 {
         struct ieee80211_local *local = sdata->local;
-        struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
+        struct sk_buff *skb;
         struct ieee80211_mgmt *mgmt;
-        u8 *pos;
-        int ie_len;
+        u8 *pos, ie_len;
+        int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
+                      sizeof(mgmt->u.action.u.mesh_action);
 
+        skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+                            hdr_len +
+                            2 + 15 /* PERR IE */);
         if (!skb)
                 return -1;
         skb_reserve(skb, local->tx_headroom + local->hw.extra_tx_headroom);
-        /* 25 is the size of the common mgmt part (24) plus the size of the
-         * common action part (1)
-         */
-        mgmt = (struct ieee80211_mgmt *)
-                skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
-        memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
+        mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
+        memset(mgmt, 0, hdr_len);
         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
                                           IEEE80211_STYPE_ACTION);