iwlwifi: mvm: support bss dynamic alloc/dealloc of queues

"DQA" is shorthand for "dynamic queue allocation". This
enables on-demand allocation of queues per RA/TID rather than
statically allocating per vif, thus allowing a potential
benefit of various factors.

Please refer to the DOC section this patch adds to sta.h to
see a more in-depth explanation of this feature.

There are many things to take into consideration when working
in DQA mode, and this patch is only one in a series. Note that
default operation mode is non-DQA mode, unless the FW
indicates that it supports DQA mode.

This patch enables support of DQA for a station connected to
an AP, and works in a non-aggregated mode.

When a frame for an unused RA/TID arrives at the driver, it
isn't TXed immediately, but deferred first until a suitable
queue is first allocated for it, and then TXed by a worker
that both allocates the queues and TXes deferred traffic.

When a STA is removed, its queues goes back into the queue
pools for reuse as needed.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 19 insertions, 2 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c
index e885db3464b0..c02c1055d534 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c
@@ -425,12 +425,17 @@ static int iwl_mvm_mac_ctxt_allocate_resources(struct iwl_mvm *mvm,
 		return 0;
 	}
 
-	/* Find available queues, and allocate them to the ACs */
+	/*
+	 * Find available queues, and allocate them to the ACs. When in
+	 * DQA-mode they aren't really used, and this is done only so the
+	 * mac80211 ieee80211_check_queues() function won't fail
+	 */
 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
 		u8 queue = find_first_zero_bit(&used_hw_queues,
 					       mvm->first_agg_queue);
 
-		if (queue >= mvm->first_agg_queue) {
+		if (!iwl_mvm_is_dqa_supported(mvm) &&
+		    queue >= mvm->first_agg_queue) {
 			IWL_ERR(mvm, "Failed to allocate queue\n");
 			ret = -EIO;
 			goto exit_fail;
@@ -495,6 +500,10 @@ int iwl_mvm_mac_ctxt_init(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
 				      IWL_MVM_TX_FIFO_MCAST, 0, wdg_timeout);
 		/* fall through */
 	default:
+		/* If DQA is supported - queues will be enabled when needed */
+		if (iwl_mvm_is_dqa_supported(mvm))
+			break;
+
 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
 			iwl_mvm_enable_ac_txq(mvm, vif->hw_queue[ac],
 					      vif->hw_queue[ac],
@@ -523,6 +532,14 @@ void iwl_mvm_mac_ctxt_release(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
 				    IWL_MAX_TID_COUNT, 0);
 		/* fall through */
 	default:
+		/*
+		 * If DQA is supported - queues were already disabled, since in
+		 * DQA-mode the queues are a property of the STA and not of the
+		 * vif, and at this point the STA was already deleted
+		 */
+		if (iwl_mvm_is_dqa_supported(mvm))
+			break;
+
 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
 			iwl_mvm_disable_txq(mvm, vif->hw_queue[ac],
 					    vif->hw_queue[ac],