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;