Merge branch 'ibmvnic-Fix-driver-reset-and-DMA-bugs'

Thomas Falcon says:

====================
ibmvnic: Fix driver reset and DMA bugs

This patch series introduces some fixes to the driver reset
routines and a patch that fixes mistakes caught by the kernel
DMA debugger.

The reset fixes include a fix to reset TX queue counters properly
after a reset as well as updates to driver reset error-handling code.
It also provides updates to the reset handling routine for redundant
backing VF failover and partition migration cases.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 98 insertions, 49 deletions

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index b492af6affc3..aad5658d79d5 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -118,6 +118,7 @@ static int init_sub_crq_irqs(struct ibmvnic_adapter *adapter);
 static int ibmvnic_init(struct ibmvnic_adapter *);
 static void release_crq_queue(struct ibmvnic_adapter *);
 static int __ibmvnic_set_mac(struct net_device *netdev, struct sockaddr *p);
+static int init_crq_queue(struct ibmvnic_adapter *adapter);
 
 struct ibmvnic_stat {
 	char name[ETH_GSTRING_LEN];
@@ -320,18 +321,16 @@ failure:
 	dev_info(dev, "replenish pools failure\n");
 	pool->free_map[pool->next_free] = index;
 	pool->rx_buff[index].skb = NULL;
-	if (!dma_mapping_error(dev, dma_addr))
-		dma_unmap_single(dev, dma_addr, pool->buff_size,
-				 DMA_FROM_DEVICE);
 
 	dev_kfree_skb_any(skb);
 	adapter->replenish_add_buff_failure++;
 	atomic_add(buffers_added, &pool->available);
 
-	if (lpar_rc == H_CLOSED) {
+	if (lpar_rc == H_CLOSED || adapter->failover_pending) {
 		/* Disable buffer pool replenishment and report carrier off if
-		 * queue is closed. Firmware guarantees that a signal will
-		 * be sent to the driver, triggering a reset.
+		 * queue is closed or pending failover.
+		 * Firmware guarantees that a signal will be sent to the
+		 * driver, triggering a reset.
 		 */
 		deactivate_rx_pools(adapter);
 		netif_carrier_off(adapter->netdev);
@@ -1071,6 +1070,14 @@ static int ibmvnic_open(struct net_device *netdev)
 	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
 	int rc;
 
+	/* If device failover is pending, just set device state and return.
+	 * Device operation will be handled by reset routine.
+	 */
+	if (adapter->failover_pending) {
+		adapter->state = VNIC_OPEN;
+		return 0;
+	}
+
 	mutex_lock(&adapter->reset_lock);
 
 	if (adapter->state != VNIC_CLOSED) {
@@ -1218,7 +1225,6 @@ static int __ibmvnic_close(struct net_device *netdev)
 	rc = set_link_state(adapter, IBMVNIC_LOGICAL_LNK_DN);
 	if (rc)
 		return rc;
-	ibmvnic_cleanup(netdev);
 	adapter->state = VNIC_CLOSED;
 	return 0;
 }
@@ -1228,8 +1234,17 @@ static int ibmvnic_close(struct net_device *netdev)
 	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
 	int rc;
 
+	/* If device failover is pending, just set device state and return.
+	 * Device operation will be handled by reset routine.
+	 */
+	if (adapter->failover_pending) {
+		adapter->state = VNIC_CLOSED;
+		return 0;
+	}
+
 	mutex_lock(&adapter->reset_lock);
 	rc = __ibmvnic_close(netdev);
+	ibmvnic_cleanup(netdev);
 	mutex_unlock(&adapter->reset_lock);
 
 	return rc;
@@ -1562,8 +1577,9 @@ static int ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev)
 		dev_kfree_skb_any(skb);
 		tx_buff->skb = NULL;
 
-		if (lpar_rc == H_CLOSED) {
-			/* Disable TX and report carrier off if queue is closed.
+		if (lpar_rc == H_CLOSED || adapter->failover_pending) {
+			/* Disable TX and report carrier off if queue is closed
+			 * or pending failover.
 			 * Firmware guarantees that a signal will be sent to the
 			 * driver, triggering a reset or some other action.
 			 */
@@ -1711,14 +1727,10 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 	old_num_rx_queues = adapter->req_rx_queues;
 	old_num_tx_queues = adapter->req_tx_queues;
 
-	if (rwi->reset_reason == VNIC_RESET_MOBILITY) {
-		rc = ibmvnic_reenable_crq_queue(adapter);
-		if (rc)
-			return 0;
-		ibmvnic_cleanup(netdev);
-	} else if (rwi->reset_reason == VNIC_RESET_FAILOVER) {
-		ibmvnic_cleanup(netdev);
-	} else {
+	ibmvnic_cleanup(netdev);
+
+	if (adapter->reset_reason != VNIC_RESET_MOBILITY &&
+	    adapter->reset_reason != VNIC_RESET_FAILOVER) {
 		rc = __ibmvnic_close(netdev);
 		if (rc)
 			return rc;
@@ -1737,6 +1749,23 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 		 */
 		adapter->state = VNIC_PROBED;
 
+		if (adapter->wait_for_reset) {
+			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 {
+			rc = ibmvnic_reset_crq(adapter);
+			if (!rc)
+				rc = vio_enable_interrupts(adapter->vdev);
+		}
+
+		if (rc) {
+			netdev_err(adapter->netdev,
+				   "Couldn't initialize crq. rc=%d\n", rc);
+			return rc;
+		}
+
 		rc = ibmvnic_init(adapter);
 		if (rc)
 			return IBMVNIC_INIT_FAILED;
@@ -1878,23 +1907,26 @@ static void __ibmvnic_reset(struct work_struct *work)
 	mutex_unlock(&adapter->reset_lock);
 }
 
-static void ibmvnic_reset(struct ibmvnic_adapter *adapter,
-			  enum ibmvnic_reset_reason reason)
+static int ibmvnic_reset(struct ibmvnic_adapter *adapter,
+			 enum ibmvnic_reset_reason reason)
 {
 	struct ibmvnic_rwi *rwi, *tmp;
 	struct net_device *netdev = adapter->netdev;
 	struct list_head *entry;
+	int ret;
 
 	if (adapter->state == VNIC_REMOVING ||
-	    adapter->state == VNIC_REMOVED) {
-		netdev_dbg(netdev, "Adapter removing, skipping reset\n");
-		return;
+	    adapter->state == VNIC_REMOVED ||
+	    adapter->failover_pending) {
+		ret = EBUSY;
+		netdev_dbg(netdev, "Adapter removing or pending failover, skipping reset\n");
+		goto err;
 	}
 
 	if (adapter->state == VNIC_PROBING) {
 		netdev_warn(netdev, "Adapter reset during probe\n");
-		adapter->init_done_rc = EAGAIN;
-		return;
+		ret = adapter->init_done_rc = EAGAIN;
+		goto err;
 	}
 
 	mutex_lock(&adapter->rwi_lock);
@@ -1904,7 +1936,8 @@ static void ibmvnic_reset(struct ibmvnic_adapter *adapter,
 		if (tmp->reset_reason == reason) {
 			netdev_dbg(netdev, "Skipping matching reset\n");
 			mutex_unlock(&adapter->rwi_lock);
-			return;
+			ret = EBUSY;
+			goto err;
 		}
 	}
 
@@ -1912,7 +1945,8 @@ static void ibmvnic_reset(struct ibmvnic_adapter *adapter,
 	if (!rwi) {
 		mutex_unlock(&adapter->rwi_lock);
 		ibmvnic_close(netdev);
-		return;
+		ret = ENOMEM;
+		goto err;
 	}
 
 	rwi->reset_reason = reason;
@@ -1921,6 +1955,12 @@ static void ibmvnic_reset(struct ibmvnic_adapter *adapter,
 
 	netdev_dbg(adapter->netdev, "Scheduling reset (reason %d)\n", reason);
 	schedule_work(&adapter->ibmvnic_reset);
+
+	return 0;
+err:
+	if (adapter->wait_for_reset)
+		adapter->wait_for_reset = false;
+	return -ret;
 }
 
 static void ibmvnic_tx_timeout(struct net_device *dev)
@@ -2055,6 +2095,8 @@ static void ibmvnic_netpoll_controller(struct net_device *dev)
 
 static int wait_for_reset(struct ibmvnic_adapter *adapter)
 {
+	int rc, ret;
+
 	adapter->fallback.mtu = adapter->req_mtu;
 	adapter->fallback.rx_queues = adapter->req_rx_queues;
 	adapter->fallback.tx_queues = adapter->req_tx_queues;
@@ -2062,11 +2104,15 @@ static int wait_for_reset(struct ibmvnic_adapter *adapter)
 	adapter->fallback.tx_entries = adapter->req_tx_entries_per_subcrq;
 
 	init_completion(&adapter->reset_done);
-	ibmvnic_reset(adapter, VNIC_RESET_CHANGE_PARAM);
 	adapter->wait_for_reset = true;
+	rc = ibmvnic_reset(adapter, VNIC_RESET_CHANGE_PARAM);
+	if (rc)
+		return rc;
 	wait_for_completion(&adapter->reset_done);
 
+	ret = 0;
 	if (adapter->reset_done_rc) {
+		ret = -EIO;
 		adapter->desired.mtu = adapter->fallback.mtu;
 		adapter->desired.rx_queues = adapter->fallback.rx_queues;
 		adapter->desired.tx_queues = adapter->fallback.tx_queues;
@@ -2074,12 +2120,15 @@ static int wait_for_reset(struct ibmvnic_adapter *adapter)
 		adapter->desired.tx_entries = adapter->fallback.tx_entries;
 
 		init_completion(&adapter->reset_done);
-		ibmvnic_reset(adapter, VNIC_RESET_CHANGE_PARAM);
+		adapter->wait_for_reset = true;
+		rc = ibmvnic_reset(adapter, VNIC_RESET_CHANGE_PARAM);
+		if (rc)
+			return ret;
 		wait_for_completion(&adapter->reset_done);
 	}
 	adapter->wait_for_reset = false;
 
-	return adapter->reset_done_rc;
+	return ret;
 }
 
 static int ibmvnic_change_mtu(struct net_device *netdev, int new_mtu)
@@ -2364,6 +2413,7 @@ static int reset_one_sub_crq_queue(struct ibmvnic_adapter *adapter,
 	}
 
 	memset(scrq->msgs, 0, 4 * PAGE_SIZE);
+	atomic_set(&scrq->used, 0);
 	scrq->cur = 0;
 
 	rc = h_reg_sub_crq(adapter->vdev->unit_address, scrq->msg_token,
@@ -2574,7 +2624,7 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter,
 	union sub_crq *next;
 	int index;
 	int i, j;
-	u8 first;
+	u8 *first;
 
 restart_loop:
 	while (pending_scrq(adapter, scrq)) {
@@ -2605,11 +2655,12 @@ restart_loop:
 				txbuff->data_dma[j] = 0;
 			}
 			/* if sub_crq was sent indirectly */
-			first = txbuff->indir_arr[0].generic.first;
-			if (first == IBMVNIC_CRQ_CMD) {
+			first = &txbuff->indir_arr[0].generic.first;
+			if (*first == IBMVNIC_CRQ_CMD) {
 				dma_unmap_single(dev, txbuff->indir_dma,
 						 sizeof(txbuff->indir_arr),
 						 DMA_TO_DEVICE);
+				*first = 0;
 			}
 
 			if (txbuff->last_frag) {
@@ -3882,9 +3933,9 @@ static int handle_login_rsp(union ibmvnic_crq *login_rsp_crq,
 	int i;
 
 	dma_unmap_single(dev, adapter->login_buf_token, adapter->login_buf_sz,
-			 DMA_BIDIRECTIONAL);
+			 DMA_TO_DEVICE);
 	dma_unmap_single(dev, adapter->login_rsp_buf_token,
-			 adapter->login_rsp_buf_sz, DMA_BIDIRECTIONAL);
+			 adapter->login_rsp_buf_sz, DMA_FROM_DEVICE);
 
 	/* If the number of queues requested can't be allocated by the
 	 * server, the login response will return with code 1. We will need
@@ -4144,7 +4195,9 @@ static void ibmvnic_handle_crq(union ibmvnic_crq *crq,
 		case IBMVNIC_CRQ_INIT:
 			dev_info(dev, "Partner initialized\n");
 			adapter->from_passive_init = true;
+			adapter->failover_pending = false;
 			complete(&adapter->init_done);
+			ibmvnic_reset(adapter, VNIC_RESET_FAILOVER);
 			break;
 		case IBMVNIC_CRQ_INIT_COMPLETE:
 			dev_info(dev, "Partner initialization complete\n");
@@ -4161,7 +4214,7 @@ static void ibmvnic_handle_crq(union ibmvnic_crq *crq,
 			ibmvnic_reset(adapter, VNIC_RESET_MOBILITY);
 		} else if (gen_crq->cmd == IBMVNIC_DEVICE_FAILOVER) {
 			dev_info(dev, "Backing device failover detected\n");
-			ibmvnic_reset(adapter, VNIC_RESET_FAILOVER);
+			adapter->failover_pending = true;
 		} else {
 			/* The adapter lost the connection */
 			dev_err(dev, "Virtual Adapter failed (rc=%d)\n",
@@ -4461,19 +4514,6 @@ static int ibmvnic_init(struct ibmvnic_adapter *adapter)
 	u64 old_num_rx_queues, old_num_tx_queues;
 	int rc;
 
-	if (adapter->resetting && !adapter->wait_for_reset) {
-		rc = ibmvnic_reset_crq(adapter);
-		if (!rc)
-			rc = vio_enable_interrupts(adapter->vdev);
-	} else {
-		rc = init_crq_queue(adapter);
-	}
-
-	if (rc) {
-		dev_err(dev, "Couldn't initialize crq. rc=%d\n", rc);
-		return rc;
-	}
-
 	adapter->from_passive_init = false;
 
 	old_num_rx_queues = adapter->req_rx_queues;
@@ -4498,7 +4538,8 @@ static int ibmvnic_init(struct ibmvnic_adapter *adapter)
 		return -1;
 	}
 
-	if (adapter->resetting && !adapter->wait_for_reset) {
+	if (adapter->resetting && !adapter->wait_for_reset &&
+	    adapter->reset_reason != VNIC_RESET_MOBILITY) {
 		if (adapter->req_rx_queues != old_num_rx_queues ||
 		    adapter->req_tx_queues != old_num_tx_queues) {
 			release_sub_crqs(adapter, 0);
@@ -4586,6 +4627,13 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
 	adapter->mac_change_pending = false;
 
 	do {
+		rc = init_crq_queue(adapter);
+		if (rc) {
+			dev_err(&dev->dev, "Couldn't initialize crq. rc=%d\n",
+				rc);
+			goto ibmvnic_init_fail;
+		}
+
 		rc = ibmvnic_init(adapter);
 		if (rc && rc != EAGAIN)
 			goto ibmvnic_init_fail;
diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h
index 89efe700eafe..99c0b58c2c39 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.h
+++ b/drivers/net/ethernet/ibm/ibmvnic.h
@@ -1108,6 +1108,7 @@ struct ibmvnic_adapter {
 	bool napi_enabled, from_passive_init;
 
 	bool mac_change_pending;
+	bool failover_pending;
 
 	struct ibmvnic_tunables desired;
 	struct ibmvnic_tunables fallback;