ibmvnic: Update reset infrastructure to support tunable parameters

Update ibmvnic reset infrastructure to include a new reset option that will
allow changing of tunable parameters. There currently is no way to request
different capabilities from the vnic server on the fly so this patch
achieves this by resetting the driver and attempting to log in with the
requested changes. If the reset operation fails, the old values of the
tunable parameters are stored in the "fallback" struct and we attempt to
login with the fallback values.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/ibm/ibmvnic.c

@@ -115,6 +115,7 @@ static int init_sub_crqs(struct ibmvnic_adapter *);
 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);
 
 struct ibmvnic_stat {
 	char name[ETH_GSTRING_LEN];
@@ -926,6 +927,11 @@ static int ibmvnic_open(struct net_device *netdev)
 
 	mutex_lock(&adapter->reset_lock);
 
+	if (adapter->mac_change_pending) {
+		__ibmvnic_set_mac(netdev, &adapter->desired.mac);
+		adapter->mac_change_pending = false;
+	}
+
 	if (adapter->state != VNIC_CLOSED) {
 		rc = ibmvnic_login(netdev);
 		if (rc) {
@@ -1426,7 +1432,7 @@ static void ibmvnic_set_multi(struct net_device *netdev)
 	}
 }
 
-static int ibmvnic_set_mac(struct net_device *netdev, void *p)
+static int __ibmvnic_set_mac(struct net_device *netdev, struct sockaddr *p)
 {
 	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
 	struct sockaddr *addr = p;
@@ -1444,6 +1450,22 @@ static int ibmvnic_set_mac(struct net_device *netdev, void *p)
 	return 0;
 }
 
+static int ibmvnic_set_mac(struct net_device *netdev, void *p)
+{
+	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
+	struct sockaddr *addr = p;
+
+	if (adapter->state != VNIC_OPEN) {
+		memcpy(&adapter->desired.mac, addr, sizeof(struct sockaddr));
+		adapter->mac_change_pending = true;
+		return 0;
+	}
+
+	__ibmvnic_set_mac(netdev, addr);
+
+	return 0;
+}
+
 /**
  * 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.
@@ -1470,6 +1492,13 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 	if (rc)
 		return rc;
 
+	if (adapter->reset_reason == VNIC_RESET_CHANGE_PARAM ||
+	    adapter->wait_for_reset) {
+		release_resources(adapter);
+		release_sub_crqs(adapter);
+		release_crq_queue(adapter);
+	}
+
 	if (adapter->reset_reason != VNIC_RESET_NON_FATAL) {
 		/* remove the closed state so when we call open it appears
 		 * we are coming from the probed state.
@@ -1492,16 +1521,23 @@ static int do_reset(struct ibmvnic_adapter *adapter,
 			return 0;
 		}
 
-		rc = reset_tx_pools(adapter);
-		if (rc)
-			return rc;
+		if (adapter->reset_reason == VNIC_RESET_CHANGE_PARAM ||
+		    adapter->wait_for_reset) {
+			rc = init_resources(adapter);
+			if (rc)
+				return rc;
+		} else {
+			rc = reset_tx_pools(adapter);
+			if (rc)
+				return rc;
 
-		rc = reset_rx_pools(adapter);
-		if (rc)
-			return rc;
+			rc = reset_rx_pools(adapter);
+			if (rc)
+				return rc;
 
-		if (reset_state == VNIC_CLOSED)
-			return 0;
+			if (reset_state == VNIC_CLOSED)
+				return 0;
+		}
 	}
 
 	rc = __ibmvnic_open(netdev);
@@ -1561,7 +1597,7 @@ static void __ibmvnic_reset(struct work_struct *work)
 	struct ibmvnic_adapter *adapter;
 	struct net_device *netdev;
 	u32 reset_state;
-	int rc;
+	int rc = 0;
 
 	adapter = container_of(work, struct ibmvnic_adapter, ibmvnic_reset);
 	netdev = adapter->netdev;
@@ -1580,6 +1616,12 @@ static void __ibmvnic_reset(struct work_struct *work)
 		rwi = get_next_rwi(adapter);
 	}
 
+	if (adapter->wait_for_reset) {
+		adapter->wait_for_reset = false;
+		adapter->reset_done_rc = rc;
+		complete(&adapter->reset_done);
+	}
+
 	if (rc) {
 		netdev_dbg(adapter->netdev, "Reset failed\n");
 		free_all_rwi(adapter);
@@ -1759,9 +1801,42 @@ static void ibmvnic_netpoll_controller(struct net_device *dev)
 }
 #endif
 
+static int wait_for_reset(struct ibmvnic_adapter *adapter)
+{
+	adapter->fallback.mtu = adapter->req_mtu;
+	adapter->fallback.rx_queues = adapter->req_rx_queues;
+	adapter->fallback.tx_queues = adapter->req_tx_queues;
+	adapter->fallback.rx_entries = adapter->req_rx_add_entries_per_subcrq;
+	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;
+	wait_for_completion(&adapter->reset_done);
+
+	if (adapter->reset_done_rc) {
+		adapter->desired.mtu = adapter->fallback.mtu;
+		adapter->desired.rx_queues = adapter->fallback.rx_queues;
+		adapter->desired.tx_queues = adapter->fallback.tx_queues;
+		adapter->desired.rx_entries = adapter->fallback.rx_entries;
+		adapter->desired.tx_entries = adapter->fallback.tx_entries;
+
+		init_completion(&adapter->reset_done);
+		ibmvnic_reset(adapter, VNIC_RESET_CHANGE_PARAM);
+		wait_for_completion(&adapter->reset_done);
+	}
+	adapter->wait_for_reset = false;
+
+	return adapter->reset_done_rc;
+}
+
 static int ibmvnic_change_mtu(struct net_device *netdev, int new_mtu)
 {
-	return -EOPNOTSUPP;
+	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
+
+	adapter->desired.mtu = new_mtu + ETH_HLEN;
+
+	return wait_for_reset(adapter);
 }
 
 static const struct net_device_ops ibmvnic_netdev_ops = {
@@ -1849,6 +1924,27 @@ static void ibmvnic_get_ringparam(struct net_device *netdev,
 	ring->rx_jumbo_pending = 0;
 }
 
+static int ibmvnic_set_ringparam(struct net_device *netdev,
+				 struct ethtool_ringparam *ring)
+{
+	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
+
+	if (ring->rx_pending > adapter->max_rx_add_entries_per_subcrq  ||
+	    ring->tx_pending > adapter->max_tx_entries_per_subcrq) {
+		netdev_err(netdev, "Invalid request.\n");
+		netdev_err(netdev, "Max tx buffers = %llu\n",
+			   adapter->max_rx_add_entries_per_subcrq);
+		netdev_err(netdev, "Max rx buffers = %llu\n",
+			   adapter->max_tx_entries_per_subcrq);
+		return -EINVAL;
+	}
+
+	adapter->desired.rx_entries = ring->rx_pending;
+	adapter->desired.tx_entries = ring->tx_pending;
+
+	return wait_for_reset(adapter);
+}
+
 static void ibmvnic_get_channels(struct net_device *netdev,
 				 struct ethtool_channels *channels)
 {
@@ -1864,6 +1960,17 @@ static void ibmvnic_get_channels(struct net_device *netdev,
 	channels->combined_count = 0;
 }
 
+static int ibmvnic_set_channels(struct net_device *netdev,
+				struct ethtool_channels *channels)
+{
+	struct ibmvnic_adapter *adapter = netdev_priv(netdev);
+
+	adapter->desired.rx_queues = channels->rx_count;
+	adapter->desired.tx_queues = channels->tx_count;
+
+	return wait_for_reset(adapter);
+}
+
 static void ibmvnic_get_strings(struct net_device *dev, u32 stringset, u8 *data)
 {
 	struct ibmvnic_adapter *adapter = netdev_priv(dev);
@@ -1960,7 +2067,9 @@ static const struct ethtool_ops ibmvnic_ethtool_ops = {
 	.set_msglevel		= ibmvnic_set_msglevel,
 	.get_link		= ibmvnic_get_link,
 	.get_ringparam		= ibmvnic_get_ringparam,
+	.set_ringparam		= ibmvnic_set_ringparam,
 	.get_channels		= ibmvnic_get_channels,
+	.set_channels		= ibmvnic_set_channels,
 	.get_strings            = ibmvnic_get_strings,
 	.get_sset_count         = ibmvnic_get_sset_count,
 	.get_ethtool_stats	= ibmvnic_get_ethtool_stats,
@@ -2426,6 +2535,7 @@ static void ibmvnic_send_req_caps(struct ibmvnic_adapter *adapter, int retry)
 {
 	struct device *dev = &adapter->vdev->dev;
 	union ibmvnic_crq crq;
+	int max_entries;
 
 	if (!retry) {
 		/* Sub-CRQ entries are 32 byte long */
@@ -2437,21 +2547,60 @@ static void ibmvnic_send_req_caps(struct ibmvnic_adapter *adapter, int retry)
 			return;
 		}
 
-		/* Get the minimum between the queried max and the entries
-		 * that fit in our PAGE_SIZE
-		 */
-		adapter->req_tx_entries_per_subcrq =
-		    adapter->max_tx_entries_per_subcrq > entries_page ?
-		    entries_page : adapter->max_tx_entries_per_subcrq;
-		adapter->req_rx_add_entries_per_subcrq =
-		    adapter->max_rx_add_entries_per_subcrq > entries_page ?
-		    entries_page : adapter->max_rx_add_entries_per_subcrq;
-
-		adapter->req_tx_queues = adapter->opt_tx_comp_sub_queues;
-		adapter->req_rx_queues = adapter->opt_rx_comp_queues;
-		adapter->req_rx_add_queues = adapter->max_rx_add_queues;
+		if (adapter->desired.mtu)
+			adapter->req_mtu = adapter->desired.mtu;
+		else
+			adapter->req_mtu = adapter->netdev->mtu + ETH_HLEN;
+
+		if (!adapter->desired.tx_entries)
+			adapter->desired.tx_entries =
+					adapter->max_tx_entries_per_subcrq;
+		if (!adapter->desired.rx_entries)
+			adapter->desired.rx_entries =
+					adapter->max_rx_add_entries_per_subcrq;
+
+		max_entries = IBMVNIC_MAX_LTB_SIZE /
+			      (adapter->req_mtu + IBMVNIC_BUFFER_HLEN);
+
+		if ((adapter->req_mtu + IBMVNIC_BUFFER_HLEN) *
+			adapter->desired.tx_entries > IBMVNIC_MAX_LTB_SIZE) {
+			adapter->desired.tx_entries = max_entries;
+		}
 
-		adapter->req_mtu = adapter->netdev->mtu + ETH_HLEN;
+		if ((adapter->req_mtu + IBMVNIC_BUFFER_HLEN) *
+			adapter->desired.rx_entries > IBMVNIC_MAX_LTB_SIZE) {
+			adapter->desired.rx_entries = max_entries;
+		}
+
+		if (adapter->desired.tx_entries)
+			adapter->req_tx_entries_per_subcrq =
+					adapter->desired.tx_entries;
+		else
+			adapter->req_tx_entries_per_subcrq =
+					adapter->max_tx_entries_per_subcrq;
+
+		if (adapter->desired.rx_entries)
+			adapter->req_rx_add_entries_per_subcrq =
+					adapter->desired.rx_entries;
+		else
+			adapter->req_rx_add_entries_per_subcrq =
+					adapter->max_rx_add_entries_per_subcrq;
+
+		if (adapter->desired.tx_queues)
+			adapter->req_tx_queues =
+					adapter->desired.tx_queues;
+		else
+			adapter->req_tx_queues =
+					adapter->opt_tx_comp_sub_queues;
+
+		if (adapter->desired.rx_queues)
+			adapter->req_rx_queues =
+					adapter->desired.rx_queues;
+		else
+			adapter->req_rx_queues =
+					adapter->opt_rx_comp_queues;
+
+		adapter->req_rx_add_queues = adapter->max_rx_add_queues;
 	}
 
 	memset(&crq, 0, sizeof(crq));
@@ -3272,6 +3421,7 @@ static int handle_login_rsp(union ibmvnic_crq *login_rsp_crq,
 			    struct ibmvnic_adapter *adapter)
 {
 	struct device *dev = &adapter->vdev->dev;
+	struct net_device *netdev = adapter->netdev;
 	struct ibmvnic_login_rsp_buffer *login_rsp = adapter->login_rsp_buf;
 	struct ibmvnic_login_buffer *login = adapter->login_buf;
 	int i;
@@ -3291,6 +3441,8 @@ static int handle_login_rsp(union ibmvnic_crq *login_rsp_crq,
 		return 0;
 	}
 
+	netdev->mtu = adapter->req_mtu - ETH_HLEN;
+
 	netdev_dbg(adapter->netdev, "Login Response Buffer:\n");
 	for (i = 0; i < (adapter->login_rsp_buf_sz - 1) / 8 + 1; i++) {
 		netdev_dbg(adapter->netdev, "%016lx\n",
@@ -3846,7 +3998,7 @@ static int ibmvnic_init(struct ibmvnic_adapter *adapter)
 	unsigned long timeout = msecs_to_jiffies(30000);
 	int rc;
 
-	if (adapter->resetting) {
+	if (adapter->resetting && !adapter->wait_for_reset) {
 		rc = ibmvnic_reset_crq(adapter);
 		if (!rc)
 			rc = vio_enable_interrupts(adapter->vdev);
@@ -3880,7 +4032,7 @@ static int ibmvnic_init(struct ibmvnic_adapter *adapter)
 		return -1;
 	}
 
-	if (adapter->resetting)
+	if (adapter->resetting && !adapter->wait_for_reset)
 		rc = reset_sub_crq_queues(adapter);
 	else
 		rc = init_sub_crqs(adapter);
@@ -3949,13 +4101,17 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
 	mutex_init(&adapter->rwi_lock);
 	adapter->resetting = false;
 
+	adapter->mac_change_pending = false;
+
 	do {
 		rc = ibmvnic_init(adapter);
 		if (rc && rc != EAGAIN)
 			goto ibmvnic_init_fail;
 	} while (rc == EAGAIN);
 
 	netdev->mtu = adapter->req_mtu - ETH_HLEN;
+	netdev->min_mtu = adapter->min_mtu - ETH_HLEN;
+	netdev->max_mtu = adapter->max_mtu - ETH_HLEN;
 
 	rc = device_create_file(&dev->dev, &dev_attr_failover);
 	if (rc)
@@ -3970,6 +4126,9 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
 	dev_info(&dev->dev, "ibmvnic registered\n");
 
 	adapter->state = VNIC_PROBED;
+
+	adapter->wait_for_reset = false;
+
 	return 0;
 
 ibmvnic_register_fail: