mac80211: sparse RCU annotations

This adds sparse RCU annotations to most of
mac80211, only the mesh code remains to be
done.

Due the the previous patches, the annotations
are pretty simple. The only thing that this
actually changes is removing the RCU usage of
key->sta in debugfs since this pointer isn't
actually an RCU-managed pointer (it only has
a single assignment done before the key even
goes live). As that is otherwise harmless, I
decided to make it part of this patch.

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

1 files changed, 12 insertions, 5 deletions

diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 55c51855ceb7..d6b566076f05 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -164,11 +164,11 @@ struct tid_ampdu_rx {
 struct sta_ampdu_mlme {
         struct mutex mtx;
         /* rx */
-        struct tid_ampdu_rx *tid_rx[STA_TID_NUM];
+        struct tid_ampdu_rx __rcu *tid_rx[STA_TID_NUM];
         unsigned long tid_rx_timer_expired[BITS_TO_LONGS(STA_TID_NUM)];
         /* tx */
         struct work_struct work;
-        struct tid_ampdu_tx *tid_tx[STA_TID_NUM];
+        struct tid_ampdu_tx __rcu *tid_tx[STA_TID_NUM];
         struct tid_ampdu_tx *tid_start_tx[STA_TID_NUM];
         u8 addba_req_num[STA_TID_NUM];
         u8 dialog_token_allocator;
@@ -243,11 +243,11 @@ struct sta_ampdu_mlme {
 struct sta_info {
         /* General information, mostly static */
         struct list_head list;
-        struct sta_info *hnext;
+        struct sta_info __rcu *hnext;
         struct ieee80211_local *local;
         struct ieee80211_sub_if_data *sdata;
-        struct ieee80211_key *gtk[NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS];
-        struct ieee80211_key *ptk;
+        struct ieee80211_key __rcu *gtk[NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS];
+        struct ieee80211_key __rcu *ptk;
         struct rate_control_ref *rate_ctrl;
         void *rate_ctrl_priv;
         spinlock_t lock;
@@ -403,6 +403,13 @@ static inline u32 get_sta_flags(struct sta_info *sta)
 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
                              struct tid_ampdu_tx *tid_tx);
 
+static inline struct tid_ampdu_tx *
+rcu_dereference_protected_tid_tx(struct sta_info *sta, int tid)
+{
+        return rcu_dereference_protected(sta->ampdu_mlme.tid_tx[tid],
+                                         lockdep_is_held(&sta->lock) ||
+                                         lockdep_is_held(&sta->ampdu_mlme.mtx));
+}
 
 #define STA_HASH_SIZE 256
 #define STA_HASH(sta) (sta[5])