qcacld: ipa: Hold cleanup till all packets completed

If driver is unloaded while descriptors are pending in IPA
hardware then there is a chance that descriptors are completed
after driver is unloaded. Fix the issue by tearing down IPA pipe
before freeing the descriptors so that ipa_teardown_sys_pipe
takes care of completing the pending descriptors and unload is
handled gracefully.

Change-Id: Ic4d4ca681e649983c025593700b1ad5a4640efa2
CRs-fixed: 710380

1 files changed, 42 insertions, 12 deletions

diff --git a/CORE/HDD/src/wlan_hdd_ipa.c b/CORE/HDD/src/wlan_hdd_ipa.c
index fdf904944ba5..fc53fbd23e27 100644
--- a/CORE/HDD/src/wlan_hdd_ipa.c
+++ b/CORE/HDD/src/wlan_hdd_ipa.c
@@ -1487,6 +1487,8 @@ static void hdd_ipa_destory_rm_resource(struct hdd_ipa_priv *hdd_ipa)
 
 static void hdd_ipa_send_skb_to_network(adf_nbuf_t skb, hdd_adapter_t *adapter)
 {
+	struct hdd_ipa_priv *hdd_ipa = ghdd_ipa;
+
 	if (!adapter || adapter->magic != WLAN_HDD_ADAPTER_MAGIC) {
 		HDD_IPA_LOG(VOS_TRACE_LEVEL_ERROR, "Invalid adapter: 0x%p",
 				adapter);
@@ -1494,6 +1496,12 @@ static void hdd_ipa_send_skb_to_network(adf_nbuf_t skb, hdd_adapter_t *adapter)
 		adf_nbuf_free(skb);
 		return;
 	}
+
+	if (hdd_ipa->hdd_ctx->isUnloadInProgress) {
+		adf_nbuf_free(skb);
+		return;
+	}
+
 	skb->dev = adapter->dev;
 	skb->protocol = eth_type_trans(skb, skb->dev);
 	skb->ip_summed = CHECKSUM_NONE;
@@ -1512,6 +1520,11 @@ static void hdd_ipa_send_pkt_to_ipa(struct hdd_ipa_priv *hdd_ipa)
 	adf_nbuf_t buf;
 	struct ipa_tx_data_desc *send_desc_head = NULL;
 
+	/* Unloading is in progress so do not proceed to send the packets to
+	 * IPA
+	 */
+	if (hdd_ipa->hdd_ctx->isUnloadInProgress)
+		return;
 
 	/* Make it priority queue request as send descriptor */
 	send_desc_head = hdd_ipa_alloc_data_desc(hdd_ipa, 1);
@@ -1990,10 +2003,12 @@ static void hdd_ipa_i2w_cb(void *priv, enum ipa_dp_evt_type evt,
 	hdd_ipa = iface_context->hdd_ipa;
 
 	/*
-	 * When SSR is going on, just drop the packets. There is no use in
-	 * queueing the packets as STA has to connect back any way
+	 * When SSR is going on or driver is unloading, just drop the packets.
+	 * During SSR, there is no use in queueing the packets as STA has to
+	 * connect back any way
 	 */
-	if (hdd_ipa->hdd_ctx->isLogpInProgress) {
+	if (hdd_ipa->hdd_ctx->isLogpInProgress ||
+			hdd_ipa->hdd_ctx->isUnloadInProgress) {
 		ipa_free_skb(ipa_tx_desc);
 		iface_context->stats.num_tx_drop++;
 		return;
@@ -2750,7 +2765,8 @@ static void hdd_ipa_rx_pipe_desc_free(void)
 	spin_unlock_bh(&hdd_ipa->q_lock);
 
 	if (i != max_desc_cnt)
-		HDD_IPA_LOG(VOS_TRACE_LEVEL_FATAL, "free desc leak");
+		HDD_IPA_LOG(VOS_TRACE_LEVEL_FATAL, "free desc leak: %u, %u", i,
+				max_desc_cnt);
 
 }
 
@@ -3120,6 +3136,13 @@ VOS_STATUS hdd_ipa_cleanup(hdd_context_t *hdd_ctx)
 	if (!hdd_ipa_is_enabled(hdd_ctx))
 		return VOS_STATUS_SUCCESS;
 
+	if (!hdd_ipa_uc_is_enabled(hdd_ipa)) {
+		unregister_inetaddr_notifier(&hdd_ipa->ipv4_notifier);
+		hdd_ipa_teardown_sys_pipe(hdd_ipa);
+	}
+
+	hdd_ipa_destory_rm_resource(hdd_ipa);
+
 #ifdef WLAN_OPEN_SOURCE
 	cancel_work_sync(&hdd_ipa->pm_work);
 #endif
@@ -3147,10 +3170,23 @@ VOS_STATUS hdd_ipa_cleanup(hdd_context_t *hdd_ctx)
 
 	hdd_ipa_debugfs_remove(hdd_ipa);
 
+	/* This should never hit but still make sure that there are no pending
+	 * descriptor in IPA hardware
+	 */
 	if (hdd_ipa->pending_hw_desc_cnt != 0) {
-		HDD_IPA_LOG(VOS_TRACE_LEVEL_FATAL, "IPA Pending write done: %d",
+		HDD_IPA_LOG(VOS_TRACE_LEVEL_ERROR,
+				"IPA Pending write done: %d Waiting!",
 				hdd_ipa->pending_hw_desc_cnt);
-		msleep(5);
+
+		for (i = 0; hdd_ipa->pending_hw_desc_cnt != 0 && i < 10; i++) {
+			usleep(100);
+		}
+
+		HDD_IPA_LOG(VOS_TRACE_LEVEL_ERROR,
+				"IPA Pending write done: desc: %d %s(%d)!",
+				hdd_ipa->pending_hw_desc_cnt,
+				hdd_ipa->pending_hw_desc_cnt == 0 ? "completed"
+				: "leak", i);
 	}
 
 #ifdef IPA_UC_OFFLOAD
@@ -3165,14 +3201,8 @@ VOS_STATUS hdd_ipa_cleanup(hdd_context_t *hdd_ctx)
 #endif /* IPA_UC_OFFLOAD */
 	{
 		hdd_ipa_rx_pipe_desc_free();
-		hdd_ipa_teardown_sys_pipe(hdd_ipa);
 	}
 
-	hdd_ipa_destory_rm_resource(hdd_ipa);
-
-	if (!hdd_ipa_uc_is_enabled(hdd_ipa)) {
-		unregister_inetaddr_notifier(&hdd_ipa->ipv4_notifier);
-	}
 	adf_os_mem_free(hdd_ipa);
 	hdd_ctx->hdd_ipa = NULL;