4 files changed, 173 insertions, 143 deletions

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index cd538d5a7986..32861036c3fc 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -212,7 +212,6 @@ void netvsc_channel_cb(void *context);
 int netvsc_poll(struct napi_struct *napi, int budget);
 
 void rndis_set_subchannel(struct work_struct *w);
-bool rndis_filter_opened(const struct netvsc_device *nvdev);
 int rndis_filter_open(struct netvsc_device *nvdev);
 int rndis_filter_close(struct netvsc_device *nvdev);
 struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 37b0a30d6b03..7472172823f3 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -555,8 +555,6 @@ void netvsc_device_remove(struct hv_device *device)
 		= rtnl_dereference(net_device_ctx->nvdev);
 	int i;
 
-	cancel_work_sync(&net_device->subchan_work);
-
 	netvsc_revoke_buf(device, net_device);
 
 	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
@@ -643,14 +641,18 @@ static void netvsc_send_tx_complete(struct netvsc_device *net_device,
 	queue_sends =
 		atomic_dec_return(&net_device->chan_table[q_idx].queue_sends);
 
-	if (net_device->destroy && queue_sends == 0)
-		wake_up(&net_device->wait_drain);
+	if (unlikely(net_device->destroy)) {
+		if (queue_sends == 0)
+			wake_up(&net_device->wait_drain);
+	} else {
+		struct netdev_queue *txq = netdev_get_tx_queue(ndev, q_idx);
 
-	if (netif_tx_queue_stopped(netdev_get_tx_queue(ndev, q_idx)) &&
-	    (hv_ringbuf_avail_percent(&channel->outbound) > RING_AVAIL_PERCENT_HIWATER ||
-	     queue_sends < 1)) {
-		netif_tx_wake_queue(netdev_get_tx_queue(ndev, q_idx));
-		ndev_ctx->eth_stats.wake_queue++;
+		if (netif_tx_queue_stopped(txq) &&
+		    (hv_ringbuf_avail_percent(&channel->outbound) > RING_AVAIL_PERCENT_HIWATER ||
+		     queue_sends < 1)) {
+			netif_tx_wake_queue(txq);
+			ndev_ctx->eth_stats.wake_queue++;
+		}
 	}
 }
 
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index faea0be18924..f28c85d212ce 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -46,7 +46,10 @@
 
 #include "hyperv_net.h"
 
-#define RING_SIZE_MIN		64
+#define RING_SIZE_MIN	64
+#define RETRY_US_LO	5000
+#define RETRY_US_HI	10000
+#define RETRY_MAX	2000	/* >10 sec */
 
 #define LINKCHANGE_INT (2 * HZ)
 #define VF_TAKEOVER_INT (HZ / 10)
@@ -123,10 +126,8 @@ static int netvsc_open(struct net_device *net)
 	}
 
 	rdev = nvdev->extension;
-	if (!rdev->link_state) {
+	if (!rdev->link_state)
 		netif_carrier_on(net);
-		netif_tx_wake_all_queues(net);
-	}
 
 	if (vf_netdev) {
 		/* Setting synthetic device up transparently sets
@@ -142,36 +143,25 @@ static int netvsc_open(struct net_device *net)
 	return 0;
 }
 
-static int netvsc_close(struct net_device *net)
+static int netvsc_wait_until_empty(struct netvsc_device *nvdev)
 {
-	struct net_device_context *net_device_ctx = netdev_priv(net);
-	struct net_device *vf_netdev
-		= rtnl_dereference(net_device_ctx->vf_netdev);
-	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
-	int ret = 0;
-	u32 aread, i, msec = 10, retry = 0, retry_max = 20;
-	struct vmbus_channel *chn;
-
-	netif_tx_disable(net);
-
-	/* No need to close rndis filter if it is removed already */
-	if (!nvdev)
-		goto out;
-
-	ret = rndis_filter_close(nvdev);
-	if (ret != 0) {
-		netdev_err(net, "unable to close device (ret %d).\n", ret);
-		return ret;
-	}
+	unsigned int retry = 0;
+	int i;
 
 	/* Ensure pending bytes in ring are read */
-	while (true) {
-		aread = 0;
+	for (;;) {
+		u32 aread = 0;
+
 		for (i = 0; i < nvdev->num_chn; i++) {
-			chn = nvdev->chan_table[i].channel;
+			struct vmbus_channel *chn
+				= nvdev->chan_table[i].channel;
+
 			if (!chn)
 				continue;
 
+			/* make sure receive not running now */
+			napi_synchronize(&nvdev->chan_table[i].napi);
+
 			aread = hv_get_bytes_to_read(&chn->inbound);
 			if (aread)
 				break;
@@ -181,22 +171,40 @@ static int netvsc_close(struct net_device *net)
 				break;
 		}
 
-		retry++;
-		if (retry > retry_max || aread == 0)
-			break;
+		if (aread == 0)
+			return 0;
 
-		msleep(msec);
+		if (++retry > RETRY_MAX)
+			return -ETIMEDOUT;
 
-		if (msec < 1000)
-			msec *= 2;
+		usleep_range(RETRY_US_LO, RETRY_US_HI);
 	}
+}
 
-	if (aread) {
-		netdev_err(net, "Ring buffer not empty after closing rndis\n");
-		ret = -ETIMEDOUT;
+static int netvsc_close(struct net_device *net)
+{
+	struct net_device_context *net_device_ctx = netdev_priv(net);
+	struct net_device *vf_netdev
+		= rtnl_dereference(net_device_ctx->vf_netdev);
+	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
+	int ret;
+
+	netif_tx_disable(net);
+
+	/* No need to close rndis filter if it is removed already */
+	if (!nvdev)
+		return 0;
+
+	ret = rndis_filter_close(nvdev);
+	if (ret != 0) {
+		netdev_err(net, "unable to close device (ret %d).\n", ret);
+		return ret;
 	}
 
-out:
+	ret = netvsc_wait_until_empty(nvdev);
+	if (ret)
+		netdev_err(net, "Ring buffer not empty after closing rndis\n");
+
 	if (vf_netdev)
 		dev_close(vf_netdev);
 
@@ -845,16 +853,81 @@ static void netvsc_get_channels(struct net_device *net,
 	}
 }
 
+static int netvsc_detach(struct net_device *ndev,
+			 struct netvsc_device *nvdev)
+{
+	struct net_device_context *ndev_ctx = netdev_priv(ndev);
+	struct hv_device *hdev = ndev_ctx->device_ctx;
+	int ret;
+
+	/* Don't try continuing to try and setup sub channels */
+	if (cancel_work_sync(&nvdev->subchan_work))
+		nvdev->num_chn = 1;
+
+	/* If device was up (receiving) then shutdown */
+	if (netif_running(ndev)) {
+		netif_tx_disable(ndev);
+
+		ret = rndis_filter_close(nvdev);
+		if (ret) {
+			netdev_err(ndev,
+				   "unable to close device (ret %d).\n", ret);
+			return ret;
+		}
+
+		ret = netvsc_wait_until_empty(nvdev);
+		if (ret) {
+			netdev_err(ndev,
+				   "Ring buffer not empty after closing rndis\n");
+			return ret;
+		}
+	}
+
+	netif_device_detach(ndev);
+
+	rndis_filter_device_remove(hdev, nvdev);
+
+	return 0;
+}
+
+static int netvsc_attach(struct net_device *ndev,
+			 struct netvsc_device_info *dev_info)
+{
+	struct net_device_context *ndev_ctx = netdev_priv(ndev);
+	struct hv_device *hdev = ndev_ctx->device_ctx;
+	struct netvsc_device *nvdev;
+	struct rndis_device *rdev;
+	int ret;
+
+	nvdev = rndis_filter_device_add(hdev, dev_info);
+	if (IS_ERR(nvdev))
+		return PTR_ERR(nvdev);
+
+	/* Note: enable and attach happen when sub-channels setup */
+
+	netif_carrier_off(ndev);
+
+	if (netif_running(ndev)) {
+		ret = rndis_filter_open(nvdev);
+		if (ret)
+			return ret;
+
+		rdev = nvdev->extension;
+		if (!rdev->link_state)
+			netif_carrier_on(ndev);
+	}
+
+	return 0;
+}
+
 static int netvsc_set_channels(struct net_device *net,
 			       struct ethtool_channels *channels)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(net);
-	struct hv_device *dev = net_device_ctx->device_ctx;
 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 	unsigned int orig, count = channels->combined_count;
 	struct netvsc_device_info device_info;
-	bool was_opened;
-	int ret = 0;
+	int ret;
 
 	/* We do not support separate count for rx, tx, or other */
 	if (count == 0 ||
@@ -871,9 +944,6 @@ static int netvsc_set_channels(struct net_device *net,
 		return -EINVAL;
 
 	orig = nvdev->num_chn;
-	was_opened = rndis_filter_opened(nvdev);
-	if (was_opened)
-		rndis_filter_close(nvdev);
 
 	memset(&device_info, 0, sizeof(device_info));
 	device_info.num_chn = count;
@@ -882,28 +952,17 @@ static int netvsc_set_channels(struct net_device *net,
 	device_info.recv_sections = nvdev->recv_section_cnt;
 	device_info.recv_section_size = nvdev->recv_section_size;
 
-	rndis_filter_device_remove(dev, nvdev);
+	ret = netvsc_detach(net, nvdev);
+	if (ret)
+		return ret;
 
-	nvdev = rndis_filter_device_add(dev, &device_info);
-	if (IS_ERR(nvdev)) {
-		ret = PTR_ERR(nvdev);
+	ret = netvsc_attach(net, &device_info);
+	if (ret) {
 		device_info.num_chn = orig;
-		nvdev = rndis_filter_device_add(dev, &device_info);
-
-		if (IS_ERR(nvdev)) {
-			netdev_err(net, "restoring channel setting failed: %ld\n",
-				   PTR_ERR(nvdev));
-			return ret;
-		}
+		if (netvsc_attach(net, &device_info))
+			netdev_err(net, "restoring channel setting failed\n");
 	}
 
-	if (was_opened)
-		rndis_filter_open(nvdev);
-
-	/* We may have missed link change notifications */
-	net_device_ctx->last_reconfig = 0;
-	schedule_delayed_work(&net_device_ctx->dwork, 0);
-
 	return ret;
 }
 
@@ -969,10 +1028,8 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 	struct net_device_context *ndevctx = netdev_priv(ndev);
 	struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
-	struct hv_device *hdev = ndevctx->device_ctx;
 	int orig_mtu = ndev->mtu;
 	struct netvsc_device_info device_info;
-	bool was_opened;
 	int ret = 0;
 
 	if (!nvdev || nvdev->destroy)
@@ -985,11 +1042,6 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 			return ret;
 	}
 
-	netif_device_detach(ndev);
-	was_opened = rndis_filter_opened(nvdev);
-	if (was_opened)
-		rndis_filter_close(nvdev);
-
 	memset(&device_info, 0, sizeof(device_info));
 	device_info.num_chn = nvdev->num_chn;
 	device_info.send_sections = nvdev->send_section_cnt;
@@ -997,35 +1049,27 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 	device_info.recv_sections = nvdev->recv_section_cnt;
 	device_info.recv_section_size = nvdev->recv_section_size;
 
-	rndis_filter_device_remove(hdev, nvdev);
+	ret = netvsc_detach(ndev, nvdev);
+	if (ret)
+		goto rollback_vf;
 
 	ndev->mtu = mtu;
 
-	nvdev = rndis_filter_device_add(hdev, &device_info);
-	if (IS_ERR(nvdev)) {
-		ret = PTR_ERR(nvdev);
-
-		/* Attempt rollback to original MTU */
-		ndev->mtu = orig_mtu;
-		nvdev = rndis_filter_device_add(hdev, &device_info);
-
-		if (vf_netdev)
-			dev_set_mtu(vf_netdev, orig_mtu);
-
-		if (IS_ERR(nvdev)) {
-			netdev_err(ndev, "restoring mtu failed: %ld\n",
-				   PTR_ERR(nvdev));
-			return ret;
-		}
-	}
+	ret = netvsc_attach(ndev, &device_info);
+	if (ret)
+		goto rollback;
 
-	if (was_opened)
-		rndis_filter_open(nvdev);
+	return 0;
 
-	netif_device_attach(ndev);
+rollback:
+	/* Attempt rollback to original MTU */
+	ndev->mtu = orig_mtu;
 
-	/* We may have missed link change notifications */
-	schedule_delayed_work(&ndevctx->dwork, 0);
+	if (netvsc_attach(ndev, &device_info))
+		netdev_err(ndev, "restoring mtu failed\n");
+rollback_vf:
+	if (vf_netdev)
+		dev_set_mtu(vf_netdev, orig_mtu);
 
 	return ret;
 }
@@ -1531,11 +1575,9 @@ static int netvsc_set_ringparam(struct net_device *ndev,
 {
 	struct net_device_context *ndevctx = netdev_priv(ndev);
 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
-	struct hv_device *hdev = ndevctx->device_ctx;
 	struct netvsc_device_info device_info;
 	struct ethtool_ringparam orig;
 	u32 new_tx, new_rx;
-	bool was_opened;
 	int ret = 0;
 
 	if (!nvdev || nvdev->destroy)
@@ -1560,34 +1602,18 @@ static int netvsc_set_ringparam(struct net_device *ndev,
 	device_info.recv_sections = new_rx;
 	device_info.recv_section_size = nvdev->recv_section_size;
 
-	netif_device_detach(ndev);
-	was_opened = rndis_filter_opened(nvdev);
-	if (was_opened)
-		rndis_filter_close(nvdev);
-
-	rndis_filter_device_remove(hdev, nvdev);
-
-	nvdev = rndis_filter_device_add(hdev, &device_info);
-	if (IS_ERR(nvdev)) {
-		ret = PTR_ERR(nvdev);
+	ret = netvsc_detach(ndev, nvdev);
+	if (ret)
+		return ret;
 
+	ret = netvsc_attach(ndev, &device_info);
+	if (ret) {
 		device_info.send_sections = orig.tx_pending;
 		device_info.recv_sections = orig.rx_pending;
-		nvdev = rndis_filter_device_add(hdev, &device_info);
-		if (IS_ERR(nvdev)) {
-			netdev_err(ndev, "restoring ringparam failed: %ld\n",
-				   PTR_ERR(nvdev));
-			return ret;
-		}
-	}
 
-	if (was_opened)
-		rndis_filter_open(nvdev);
-	netif_device_attach(ndev);
-
-	/* We may have missed link change notifications */
-	ndevctx->last_reconfig = 0;
-	schedule_delayed_work(&ndevctx->dwork, 0);
+		if (netvsc_attach(ndev, &device_info))
+			netdev_err(ndev, "restoring ringparam failed");
+	}
 
 	return ret;
 }
@@ -2072,8 +2098,8 @@ no_net:
 static int netvsc_remove(struct hv_device *dev)
 {
 	struct net_device_context *ndev_ctx;
-	struct net_device *vf_netdev;
-	struct net_device *net;
+	struct net_device *vf_netdev, *net;
+	struct netvsc_device *nvdev;
 
 	net = hv_get_drvdata(dev);
 	if (net == NULL) {
@@ -2083,10 +2109,14 @@ static int netvsc_remove(struct hv_device *dev)
 
 	ndev_ctx = netdev_priv(net);
 
-	netif_device_detach(net);
-
 	cancel_delayed_work_sync(&ndev_ctx->dwork);
 
+	rcu_read_lock();
+	nvdev = rcu_dereference(ndev_ctx->nvdev);
+
+	if  (nvdev)
+		cancel_work_sync(&nvdev->subchan_work);
+
 	/*
 	 * Call to the vsc driver to let it know that the device is being
 	 * removed. Also blocks mtu and channel changes.
@@ -2096,11 +2126,13 @@ static int netvsc_remove(struct hv_device *dev)
 	if (vf_netdev)
 		netvsc_unregister_vf(vf_netdev);
 
+	if (nvdev)
+		rndis_filter_device_remove(dev, nvdev);
+
 	unregister_netdevice(net);
 
-	rndis_filter_device_remove(dev,
-				   rtnl_dereference(ndev_ctx->nvdev));
 	rtnl_unlock();
+	rcu_read_unlock();
 
 	hv_set_drvdata(dev, NULL);
 
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 963314eb3226..a6ec41c399d6 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1118,6 +1118,7 @@ void rndis_set_subchannel(struct work_struct *w)
 	for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
 		ndev_ctx->tx_table[i] = i % nvdev->num_chn;
 
+	netif_device_attach(ndev);
 	rtnl_unlock();
 	return;
 
@@ -1128,6 +1129,8 @@ failed:
 
 	nvdev->max_chn = 1;
 	nvdev->num_chn = 1;
+
+	netif_device_attach(ndev);
 unlock:
 	rtnl_unlock();
 }
@@ -1330,6 +1333,10 @@ out:
 		net_device->num_chn = 1;
 	}
 
+	/* No sub channels, device is ready */
+	if (net_device->num_chn == 1)
+		netif_device_attach(net);
+
 	return net_device;
 
 err_dev_remv:
@@ -1342,9 +1349,6 @@ void rndis_filter_device_remove(struct hv_device *dev,
 {
 	struct rndis_device *rndis_dev = net_dev->extension;
 
-	/* Don't try and setup sub channels if about to halt */
-	cancel_work_sync(&net_dev->subchan_work);
-
 	/* Halt and release the rndis device */
 	rndis_filter_halt_device(rndis_dev);
 
@@ -1368,10 +1372,3 @@ int rndis_filter_close(struct netvsc_device *nvdev)
 
 	return rndis_filter_close_device(nvdev->extension);
 }
-
-bool rndis_filter_opened(const struct netvsc_device *nvdev)
-{
-	const struct rndis_device *dev = nvdev->extension;
-
-	return dev->state == RNDIS_DEV_DATAINITIALIZED;
-}