iwlwifi: mvm: fix mac80211 queue tracking

In the driver, we track which hardware queue is associated with
which mac80211 "hw_queue", in order to be able to stop and wake
it. When moving these bitmaps out of the queue_info structures,
the type of the bitmap was erroneously changed from u32 to u8,
presumably in order to save memory.

Turns out that u32 isn't needed, because the highest queue we
can ever tell mac80211 is always < 16, but a u16 definitely is
needed, queues >=8 do happen.

While at it, throw a BUILD_BUG_ON() into the place where we set
the limit (mvm->first_agg_queue) and a warning when it actually
gets put into the bitmap.

The consequence of this bug is that full HW queues associated
with such a too-high mac80211 number never stop higher layer
queues when full, and thus would simply drop all packets that
couldn't be enqueued to the hardware queue.

Fixes: 34e10860ae8d ("iwlwifi: mvm: remove references to queue_info in new TX path")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
index 0f0cd6c9ce8be18dbe3222c2328d1533a40b04a1..6b8f7817391dfec26e9182d6efe5b533079f20f4 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
@@ -789,7 +789,7 @@ struct iwl_mvm {
                u64 on_time_scan;
        } radio_stats, accu_radio_stats;
 
-       u8 hw_queue_to_mac80211[IWL_MAX_TVQM_QUEUES];
+       u16 hw_queue_to_mac80211[IWL_MAX_TVQM_QUEUES];
 
        struct {
                u8 hw_queue_refcount;

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
index 32233cba6786060d6943f98ba5af5f6ba1288d0e..1799a3d367f9214101cf3afc0a04071d3517ca1e 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c
@@ -602,9 +602,13 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg,
                if (mvm->cfg->base_params->num_of_queues == 16) {
                        mvm->aux_queue = 11;
                        mvm->first_agg_queue = 12;
+                       BUILD_BUG_ON(BITS_PER_BYTE *
+                                    sizeof(mvm->hw_queue_to_mac80211[0]) < 12);
                } else {
                        mvm->aux_queue = 15;
                        mvm->first_agg_queue = 16;
+                       BUILD_BUG_ON(BITS_PER_BYTE *
+                                    sizeof(mvm->hw_queue_to_mac80211[0]) < 16);
                }
        } else {
                mvm->aux_queue = IWL_MVM_DQA_AUX_QUEUE;

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/utils.c b/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
index 0093e78dd571bd21ac926948f69d519aba690e79..bd2596fdafda3ebeea558e2e56bf5484cfcd279f 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
@@ -698,7 +698,13 @@ static bool iwl_mvm_update_txq_mapping(struct iwl_mvm *mvm, int queue,
        if (mvm->queue_info[queue].hw_queue_refcount > 0)
                enable_queue = false;
 
-       mvm->hw_queue_to_mac80211[queue] |= BIT(mac80211_queue);
+       if (mac80211_queue != IEEE80211_INVAL_HW_QUEUE) {
+               WARN(mac80211_queue >=
+                    BITS_PER_BYTE * sizeof(mvm->hw_queue_to_mac80211[0]),
+                    "cannot track mac80211 queue %d (queue %d, sta %d, tid %d)\n",
+                    mac80211_queue, queue, sta_id, tid);
+               mvm->hw_queue_to_mac80211[queue] |= BIT(mac80211_queue);
+       }
 
        mvm->queue_info[queue].hw_queue_refcount++;
        mvm->queue_info[queue].tid_bitmap |= BIT(tid);