mac80211: move fragment flag to info flag as dont-fragment

The purpose of this is two-fold:
 1) by moving it out of tx_data.flags, we can in
    another patch move the radiotap parsing so it
    no longer is in the hotpath
 2) if a device implements fragmentation but can
    optionally skip it, the radiotap request for
    not doing fragmentation may be honoured

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 16 insertions, 27 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index a6cbc0acccdc..4ad16573ecd6 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -136,7 +136,6 @@ typedef unsigned __bitwise__ ieee80211_tx_result;
 #define TX_DROP         ((__force ieee80211_tx_result) 1u)
 #define TX_QUEUED       ((__force ieee80211_tx_result) 2u)
 
-#define IEEE80211_TX_FRAGMENTED         BIT(0)
 #define IEEE80211_TX_UNICAST            BIT(1)
 #define IEEE80211_TX_PS_BUFFERED        BIT(2)
 
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 6f2254a554e7..7f7d45cf77d1 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -898,7 +898,10 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
         int hdrlen;
         int fragnum;
 
-        if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
+        if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
+                return TX_CONTINUE;
+
+        if (tx->local->ops->set_frag_threshold)
                 return TX_CONTINUE;
 
         /*
@@ -911,7 +914,7 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
 
         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 
-        /* internal error, why is TX_FRAGMENTED set? */
+        /* internal error, why isn't DONTFRAG set? */
         if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
                 return TX_DROP;
 
@@ -1050,17 +1053,13 @@ static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
         struct ieee80211_radiotap_iterator iterator;
         struct ieee80211_radiotap_header *rthdr =
                 (struct ieee80211_radiotap_header *) skb->data;
-        bool hw_frag;
         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
         int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
                                                    NULL);
         u16 txflags;
 
-        info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
-        tx->flags &= ~IEEE80211_TX_FRAGMENTED;
-
-        /* packet is fragmented in HW if we have a non-NULL driver callback */
-        hw_frag = (tx->local->ops->set_frag_threshold != NULL);
+        info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
+                       IEEE80211_TX_CTL_DONTFRAG;
 
         /*
          * for every radiotap entry that is present
@@ -1098,9 +1097,8 @@ static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
                         }
                         if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
                                 info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
-                        if ((*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG) &&
-                                                                !hw_frag)
-                                tx->flags |= IEEE80211_TX_FRAGMENTED;
+                        if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
+                                info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
                         break;
 
                 case IEEE80211_RADIOTAP_TX_FLAGS:
@@ -1206,13 +1204,6 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
         tx->local = local;
         tx->sdata = sdata;
         tx->channel = local->hw.conf.channel;
-        /*
-         * Set this flag (used below to indicate "automatic fragmentation"),
-         * it will be cleared/left by radiotap as desired.
-         * Only valid when fragmentation is done by the stack.
-         */
-        if (!local->ops->set_frag_threshold)
-                tx->flags |= IEEE80211_TX_FRAGMENTED;
 
         /* process and remove the injection radiotap header */
         if (unlikely(info->flags & IEEE80211_TX_INTFL_HAS_RADIOTAP)) {
@@ -1281,13 +1272,11 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
                  */
         }
 
-        if (tx->flags & IEEE80211_TX_FRAGMENTED) {
-                if ((tx->flags & IEEE80211_TX_UNICAST) &&
-                    skb->len + FCS_LEN > local->hw.wiphy->frag_threshold &&
-                    !(info->flags & IEEE80211_TX_CTL_AMPDU))
-                        tx->flags |= IEEE80211_TX_FRAGMENTED;
-                else
-                        tx->flags &= ~IEEE80211_TX_FRAGMENTED;
+        if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
+                if (!(tx->flags & IEEE80211_TX_UNICAST) ||
+                    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
+                    info->flags & IEEE80211_TX_CTL_AMPDU)
+                        info->flags |= IEEE80211_TX_CTL_DONTFRAG;
         }
 
         if (!tx->sta)
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 7bc8702808fa..f614ce7bb6e3 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -53,7 +53,8 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
         }
 
         if (info->control.hw_key &&
-            !(tx->flags & IEEE80211_TX_FRAGMENTED) &&
+            (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
+             tx->local->ops->set_frag_threshold) &&
             !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
                 /* hwaccel - with no need for SW-generated MMIC */
                 return TX_CONTINUE;