From 3f5ec374ae3f3d5381622e29319a22c4ecd09413 Mon Sep 17 00:00:00 2001

From: Lijun Pan <ljp@linux.ibm.com>

Date: Wed, 6 Jan 2021 15:35:14 -0600

Subject: [PATCH] ibmvnic: merge do_change_param_reset into do_reset

References: bsc#1184114 ltc#192237 bsc#1183871 ltc#192139

Patch-mainline: v5.12-rc1

Git-commit: 3f5ec374ae3f3d5381622e29319a22c4ecd09413

Commit b27507bb59ed ("net/ibmvnic: unlock rtnl_lock in reset so

linkwatch_event can run") introduced do_change_param_reset function to

solve the rtnl lock issue. Majority of the code in do_change_param_reset

duplicates do_reset. Also, we can handle the rtnl lock issue in do_reset

itself. Hence merge do_change_param_reset back into do_reset to clean up

the code.

Signed-off-by: Lijun Pan <ljp@linux.ibm.com>

Link: https://lore.kernel.org/r/20210106213514.76027-1-ljp@linux.ibm.com

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Acked-by: Michal Suchanek <msuchanek@suse.de>

---

 drivers/net/ethernet/ibm/ibmvnic.c | 154 +++++++++--------------------

 1 file changed, 44 insertions(+), 110 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c

index 9778c83150f1..aed985e08e8a 100644

--- a/drivers/net/ethernet/ibm/ibmvnic.c

+++ b/drivers/net/ethernet/ibm/ibmvnic.c

@@ -1925,92 +1925,6 @@ static int ibmvnic_set_mac(struct net_device *netdev, void *p)

 	return rc;

 }

-/**

- * do_change_param_reset returns zero if we are able to keep processing reset

- * events, or non-zero if we hit a fatal error and must halt.

- */

-static int do_change_param_reset(struct ibmvnic_adapter *adapter,

-				 struct ibmvnic_rwi *rwi,

-				 u32 reset_state)

-{

-	struct net_device *netdev = adapter->netdev;

-	int i, rc;

-

-	netdev_dbg(adapter->netdev, "Change param resetting driver (%d)\n",

-		   rwi->reset_reason);

-

-	netif_carrier_off(netdev);

-	adapter->reset_reason = rwi->reset_reason;

-

-	ibmvnic_cleanup(netdev);

-

-	if (reset_state == VNIC_OPEN) {

-		rc = __ibmvnic_close(netdev);

-		if (rc)

-			goto out;

-	}

-

-	release_resources(adapter);

-	release_sub_crqs(adapter, 1);

-	release_crq_queue(adapter);

-

-	adapter->state = VNIC_PROBED;

-

-	rc = init_crq_queue(adapter);

-

-	if (rc) {

-		netdev_err(adapter->netdev,

-			   "Couldn't initialize crq. rc=%d\n", rc);

-		return rc;

-	}

-

-	rc = ibmvnic_reset_init(adapter, true);

-	if (rc) {

-		rc = IBMVNIC_INIT_FAILED;

-		goto out;

-	}

-

-	/* If the adapter was in PROBE state prior to the reset,

-	 * exit here.

-	 */

-	if (reset_state == VNIC_PROBED)

-		goto out;

-

-	rc = ibmvnic_login(netdev);

-	if (rc) {

-		goto out;

-	}

-

-	rc = init_resources(adapter);

-	if (rc)

-		goto out;

-

-	ibmvnic_disable_irqs(adapter);

-

-	adapter->state = VNIC_CLOSED;

-

-	if (reset_state == VNIC_CLOSED)

-		return 0;

-

-	rc = __ibmvnic_open(netdev);

-	if (rc) {

-		rc = IBMVNIC_OPEN_FAILED;

-		goto out;

-	}

-

-	/* refresh device's multicast list */

-	ibmvnic_set_multi(netdev);

-

-	/* kick napi */

-	for (i = 0; i < adapter->req_rx_queues; i++)

-		napi_schedule(&adapter->napi[i]);

-

-out:

-	if (rc)

-		adapter->state = reset_state;

-	return rc;

-}

-

 /**

  * do_reset returns zero if we are able to keep processing reset events, or

  * non-zero if we hit a fatal error and must halt.

@@ -2028,7 +1942,11 @@ static int do_reset(struct ibmvnic_adapter *adapter,

 		   adapter->state, adapter->failover_pending,

 		   rwi->reset_reason, reset_state);

-	rtnl_lock();

+	adapter->reset_reason = rwi->reset_reason;

+	/* requestor of VNIC_RESET_CHANGE_PARAM already has the rtnl lock */

+	if (!(adapter->reset_reason == VNIC_RESET_CHANGE_PARAM))

+		rtnl_lock();

+

 	/*

 	 * Now that we have the rtnl lock, clear any pending failover.

 	 * This will ensure ibmvnic_open() has either completed or will

@@ -2038,7 +1956,6 @@ static int do_reset(struct ibmvnic_adapter *adapter,

 		adapter->failover_pending = false;

 	netif_carrier_off(netdev);

-	adapter->reset_reason = rwi->reset_reason;

 	old_num_rx_queues = adapter->req_rx_queues;

 	old_num_tx_queues = adapter->req_tx_queues;

@@ -2050,25 +1967,37 @@ static int do_reset(struct ibmvnic_adapter *adapter,

 	if (reset_state == VNIC_OPEN &&

 	    adapter->reset_reason != VNIC_RESET_MOBILITY &&

 	    adapter->reset_reason != VNIC_RESET_FAILOVER) {

-		adapter->state = VNIC_CLOSING;

+		if (adapter->reset_reason == VNIC_RESET_CHANGE_PARAM) {

+			rc = __ibmvnic_close(netdev);

+			if (rc)

+				goto out;

+		} else {

+			adapter->state = VNIC_CLOSING;

-		/* Release the RTNL lock before link state change and

-		 * re-acquire after the link state change to allow

-		 * linkwatch_event to grab the RTNL lock and run during

-		 * a reset.

-		 */

-		rtnl_unlock();

-		rc = set_link_state(adapter, IBMVNIC_LOGICAL_LNK_DN);

-		rtnl_lock();

-		if (rc)

-			goto out;

+			/* Release the RTNL lock before link state change and

+			 * re-acquire after the link state change to allow

+			 * linkwatch_event to grab the RTNL lock and run during

+			 * a reset.

+			 */

+			rtnl_unlock();

+			rc = set_link_state(adapter, IBMVNIC_LOGICAL_LNK_DN);

+			rtnl_lock();

+			if (rc)

+				goto out;

-		if (adapter->state != VNIC_CLOSING) {

-			rc = -1;

-			goto out;

+			if (adapter->state != VNIC_CLOSING) {

+				rc = -1;

+				goto out;

+			}

+

+			adapter->state = VNIC_CLOSED;

 		}

+	}

-		adapter->state = VNIC_CLOSED;

+	if (adapter->reset_reason == VNIC_RESET_CHANGE_PARAM) {

+		release_resources(adapter);

+		release_sub_crqs(adapter, 1);

+		release_crq_queue(adapter);

 	}

 	if (adapter->reset_reason != VNIC_RESET_NON_FATAL) {

@@ -2077,7 +2006,9 @@ static int do_reset(struct ibmvnic_adapter *adapter,

 		 */

 		adapter->state = VNIC_PROBED;

-		if (adapter->reset_reason == VNIC_RESET_MOBILITY) {

+		if (adapter->reset_reason == VNIC_RESET_CHANGE_PARAM) {

+			rc = init_crq_queue(adapter);

+		} else if (adapter->reset_reason == VNIC_RESET_MOBILITY) {

 			rc = ibmvnic_reenable_crq_queue(adapter);

 			release_sub_crqs(adapter, 1);

 		} else {

@@ -2116,7 +2047,11 @@ static int do_reset(struct ibmvnic_adapter *adapter,

 			goto out;

 		}

-		if (adapter->req_rx_queues != old_num_rx_queues ||

+		if (adapter->reset_reason == VNIC_RESET_CHANGE_PARAM) {

+			rc = init_resources(adapter);

+			if (rc)

+				goto out;

+		} else if (adapter->req_rx_queues != old_num_rx_queues ||

 		    adapter->req_tx_queues != old_num_tx_queues ||

 		    adapter->req_rx_add_entries_per_subcrq !=

 		    old_num_rx_slots ||

@@ -2181,7 +2116,9 @@ static int do_reset(struct ibmvnic_adapter *adapter,

 	/* restore the adapter state if reset failed */

 	if (rc)

 		adapter->state = reset_state;

-	rtnl_unlock();

+	/* requestor of VNIC_RESET_CHANGE_PARAM should still hold the rtnl lock */

+	if (!(adapter->reset_reason == VNIC_RESET_CHANGE_PARAM))

+		rtnl_unlock();

 	netdev_dbg(adapter->netdev, "[S:%d FOP:%d] Reset done, rc %d\n",

 		   adapter->state, adapter->failover_pending, rc);

@@ -2312,10 +2249,7 @@ static void __ibmvnic_reset(struct work_struct *work)

 		}

 		spin_unlock_irqrestore(&adapter->state_lock, flags);

-		if (rwi->reset_reason == VNIC_RESET_CHANGE_PARAM) {

-			/* CHANGE_PARAM requestor holds rtnl_lock */

-			rc = do_change_param_reset(adapter, rwi, reset_state);

-		} else if (adapter->force_reset_recovery) {

+		if (adapter->force_reset_recovery) {

 			/*

 			 * Since we are doing a hard reset now, clear the

 			 * failover_pending flag so we don't ignore any

-- 

2.26.2