[PATCH 19/25] Staging: hv: netvsc: Get rid of the usage of the ext field in struct hv_device

["K. Y. Srinivasan" <kys@microsoft.com>]

Now, eliminate the usage of ext field in struct  hv_device for netvsc driver.
We do this by registering pointer to struct netvsc_device as the driver
specific data and eliminating the current usage of driver specific data
to save and retrieve the pointer to struct net_device.
Additionally, all access to the driver specific data is through
the vmbus wrapper functions. As part of this cleanup, we also get rid
of some unnecessary debug print statements.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
 drivers/staging/hv/hyperv_net.h   |    2 +
 drivers/staging/hv/netvsc.c       |   90 +++++++++++++++++++-----------------
 drivers/staging/hv/netvsc_drv.c   |   29 ++++++++++--
 drivers/staging/hv/rndis_filter.c |   36 +++++++++++----
 4 files changed, 100 insertions(+), 57 deletions(-)

diff --git a/drivers/staging/hv/hyperv_net.h b/drivers/staging/hv/hyperv_net.h
index af8a37f..366dd2b 100644
--- a/drivers/staging/hv/hyperv_net.h
+++ b/drivers/staging/hv/hyperv_net.h
@@ -392,6 +392,8 @@ struct netvsc_device {
 	struct nvsp_message revoke_packet;
 	/* unsigned char HwMacAddr[HW_MACADDR_LEN]; */
 
+	struct net_device *ndev;
+
 	/* Holds rndis device info */
 	void *extension;
 };
diff --git a/drivers/staging/hv/netvsc.c b/drivers/staging/hv/netvsc.c
index 115629f..b046873 100644
--- a/drivers/staging/hv/netvsc.c
+++ b/drivers/staging/hv/netvsc.c
@@ -35,6 +35,8 @@
 static struct netvsc_device *alloc_net_device(struct hv_device *device)
 {
 	struct netvsc_device *net_device;
+	struct net_device *ndev =
+		(struct net_device *)hv_get_drvdata(device);
 
 	net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
 	if (!net_device)
@@ -43,8 +45,9 @@ static struct netvsc_device *alloc_net_device(struct hv_device *device)
 
 	net_device->destroy = false;
 	net_device->dev = device;
-	device->ext = net_device;
+	net_device->ndev = ndev;
 
+	hv_set_drvdata(device, net_device);
 	return net_device;
 }
 
@@ -52,7 +55,8 @@ static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
 {
 	struct netvsc_device *net_device;
 
-	net_device = device->ext;
+	net_device =
+		(struct netvsc_device *)hv_get_drvdata(device);
 	if (net_device && net_device->destroy)
 		net_device = NULL;
 
@@ -63,7 +67,8 @@ static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
 {
 	struct netvsc_device *net_device;
 
-	net_device = device->ext;
+	net_device =
+		(struct netvsc_device *)hv_get_drvdata(device);
 
 	if (!net_device)
 		goto get_in_err;
@@ -81,7 +86,7 @@ static int netvsc_destroy_recv_buf(struct netvsc_device *net_device)
 {
 	struct nvsp_message *revoke_packet;
 	int ret = 0;
-	struct net_device *ndev = dev_get_drvdata(&net_device->dev->device);
+	struct net_device *ndev = net_device->ndev;
 
 	/*
 	 * If we got a section count, it means we received a
@@ -153,14 +158,12 @@ static int netvsc_init_recv_buf(struct hv_device *device)
 	int t;
 	struct netvsc_device *net_device;
 	struct nvsp_message *init_packet;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	net_device = get_outbound_net_device(device);
-	if (!net_device) {
-		netdev_err(ndev, "unable to get net device..."
-			   "device being destroyed?\n");
+	if (!net_device)
 		return -ENODEV;
-	}
+	ndev = net_device->ndev;
 
 	net_device->recv_buf =
 		(void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
@@ -269,14 +272,12 @@ static int netvsc_connect_vsp(struct hv_device *device)
 	struct netvsc_device *net_device;
 	struct nvsp_message *init_packet;
 	int ndis_version;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	net_device = get_outbound_net_device(device);
-	if (!net_device) {
-		netdev_err(ndev, "unable to get net device..."
-			   "device being destroyed?\n");
+	if (!net_device)
 		return -ENODEV;
-	}
+	ndev = net_device->ndev;
 
 	init_packet = &net_device->channel_init_pkt;
 
@@ -357,7 +358,7 @@ int netvsc_device_remove(struct hv_device *device)
 	struct hv_netvsc_packet *netvsc_packet, *pos;
 	unsigned long flags;
 
-	net_device = (struct netvsc_device *)device->ext;
+	net_device = (struct netvsc_device *)hv_get_drvdata(device);
 	spin_lock_irqsave(&device->channel->inbound_lock, flags);
 	net_device->destroy = true;
 	spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
@@ -381,7 +382,7 @@ int netvsc_device_remove(struct hv_device *device)
 	 */
 
 	spin_lock_irqsave(&device->channel->inbound_lock, flags);
-	device->ext = NULL;
+	hv_set_drvdata(device, NULL);
 	spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
 
 	/* At this point, no one should be accessing netDevice except in here */
@@ -407,14 +408,12 @@ static void netvsc_send_completion(struct hv_device *device,
 	struct netvsc_device *net_device;
 	struct nvsp_message *nvsp_packet;
 	struct hv_netvsc_packet *nvsc_packet;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	net_device = get_inbound_net_device(device);
-	if (!net_device) {
-		netdev_err(ndev, "unable to get net device..."
-			   "device being destroyed?\n");
+	if (!net_device)
 		return;
-	}
+	ndev = net_device->ndev;
 
 	nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 			(packet->offset8 << 3));
@@ -452,14 +451,12 @@ int netvsc_send(struct hv_device *device,
 	struct netvsc_device *net_device;
 	int ret = 0;
 	struct nvsp_message sendMessage;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	net_device = get_outbound_net_device(device);
-	if (!net_device) {
-		netdev_err(ndev, "net device (%p) shutting down..."
-			   "ignoring outbound packets\n", net_device);
+	if (!net_device)
 		return -ENODEV;
-	}
+	ndev = net_device->ndev;
 
 	sendMessage.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 	if (packet->is_data_pkt) {
@@ -506,7 +503,11 @@ static void netvsc_send_recv_completion(struct hv_device *device,
 	struct nvsp_message recvcompMessage;
 	int retries = 0;
 	int ret;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
+	struct netvsc_device *net_device =
+		(struct netvsc_device *)hv_get_drvdata(device);
+
+	ndev = net_device->ndev;
 
 	recvcompMessage.hdr.msg_type =
 				NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
@@ -552,7 +553,7 @@ static void netvsc_receive_completion(void *context)
 	u64 transaction_id = 0;
 	bool fsend_receive_comp = false;
 	unsigned long flags;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	/*
 	 * Even though it seems logical to do a GetOutboundNetDevice() here to
@@ -560,11 +561,9 @@ static void netvsc_receive_completion(void *context)
 	 * since we may have disable outbound traffic already.
 	 */
 	net_device = get_inbound_net_device(device);
-	if (!net_device) {
-		netdev_err(ndev, "unable to get net device..."
-			   "device being destroyed?\n");
+	if (!net_device)
 		return;
-	}
+	ndev = net_device->ndev;
 
 	/* Overloading use of the lock. */
 	spin_lock_irqsave(&net_device->recv_pkt_list_lock, flags);
@@ -607,16 +606,14 @@ static void netvsc_receive(struct hv_device *device,
 	int i, j;
 	int count = 0, bytes_remain = 0;
 	unsigned long flags;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	LIST_HEAD(listHead);
 
 	net_device = get_inbound_net_device(device);
-	if (!net_device) {
-		netdev_err(ndev, "unable to get net device..."
-			   "device being destroyed?\n");
+	if (!net_device)
 		return;
-	}
+	ndev = net_device->ndev;
 
 	/*
 	 * All inbound packets other than send completion should be xfer page
@@ -784,7 +781,7 @@ static void netvsc_channel_cb(void *context)
 	struct vmpacket_descriptor *desc;
 	unsigned char *buffer;
 	int bufferlen = NETVSC_PACKET_SIZE;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
 			 GFP_ATOMIC);
@@ -793,11 +790,9 @@ static void netvsc_channel_cb(void *context)
 	buffer = packet;
 
 	net_device = get_inbound_net_device(device);
-	if (!net_device) {
-		netdev_err(ndev, "net device (%p) shutting down..."
-			   "ignoring inbound packets\n", net_device);
+	if (!net_device)
 		goto out;
-	}
+	ndev = net_device->ndev;
 
 	do {
 		ret = vmbus_recvpacket_raw(device->channel, buffer, bufferlen,
@@ -871,7 +866,7 @@ int netvsc_device_add(struct hv_device *device, void *additional_info)
 	((struct netvsc_device_info *)additional_info)->ring_size;
 	struct netvsc_device *net_device;
 	struct hv_netvsc_packet *packet, *pos;
-	struct net_device *ndev = dev_get_drvdata(&device->device);
+	struct net_device *ndev;
 
 	net_device = alloc_net_device(device);
 	if (!net_device) {
@@ -879,6 +874,15 @@ int netvsc_device_add(struct hv_device *device, void *additional_info)
 		goto cleanup;
 	}
 
+	/*
+	 * Coming into this function, struct net_device * is
+	 * registered as the driver private data.
+	 * In alloc_net_device(), we register struct netvsc_device *
+	 * as the driver private data and stash away struct net_device *
+	 * in struct netvsc_device *.
+	 */
+	ndev = net_device->ndev;
+
 	/* Initialize the NetVSC channel extension */
 	net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 	spin_lock_init(&net_device->recv_pkt_list_lock);
diff --git a/drivers/staging/hv/netvsc_drv.c b/drivers/staging/hv/netvsc_drv.c
index d0189a3..917bae5 100644
--- a/drivers/staging/hv/netvsc_drv.c
+++ b/drivers/staging/hv/netvsc_drv.c
@@ -203,8 +203,13 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 void netvsc_linkstatus_callback(struct hv_device *device_obj,
 				       unsigned int status)
 {
-	struct net_device *net = dev_get_drvdata(&device_obj->device);
+	struct net_device *net;
 	struct net_device_context *ndev_ctx;
+	struct netvsc_device *net_device;
+
+	net_device =
+		(struct netvsc_device *)hv_get_drvdata(device_obj);
+	net = net_device->ndev;
 
 	if (!net) {
 		netdev_err(net, "got link status but net device "
@@ -236,6 +241,11 @@ int netvsc_recv_callback(struct hv_device *device_obj,
 	void *data;
 	int i;
 	unsigned long flags;
+	struct netvsc_device *net_device;
+
+	net_device =
+		(struct netvsc_device *)hv_get_drvdata(device_obj);
+	net = net_device->ndev;
 
 	if (!net) {
 		netdev_err(net, "got receive callback but net device"
@@ -322,9 +332,13 @@ static void netvsc_send_garp(struct work_struct *w)
 {
 	struct net_device_context *ndev_ctx;
 	struct net_device *net;
+	struct netvsc_device *net_device;
 
 	ndev_ctx = container_of(w, struct net_device_context, dwork.work);
-	net = dev_get_drvdata(&ndev_ctx->device_ctx->device);
+	net_device =
+		(struct netvsc_device *)
+		hv_get_drvdata(ndev_ctx->device_ctx);
+	net = net_device->ndev;
 	netif_notify_peers(net);
 }
 
@@ -347,7 +361,7 @@ static int netvsc_probe(struct hv_device *dev,
 	net_device_ctx = netdev_priv(net);
 	net_device_ctx->device_ctx = dev;
 	atomic_set(&net_device_ctx->avail, ring_size);
-	dev_set_drvdata(&dev->device, net);
+	hv_set_drvdata(dev, net);
 	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_send_garp);
 
 	net->netdev_ops = &device_ops;
@@ -373,7 +387,7 @@ static int netvsc_probe(struct hv_device *dev,
 		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
 		unregister_netdev(net);
 		free_netdev(net);
-		dev_set_drvdata(&dev->device, NULL);
+		hv_set_drvdata(dev, NULL);
 		return ret;
 	}
 	memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
@@ -387,8 +401,13 @@ out:
 static int netvsc_remove(struct hv_device *dev,
 			const struct hv_vmbus_device_id *dev_id)
 {
-	struct net_device *net = dev_get_drvdata(&dev->device);
+	struct net_device *net;
 	struct net_device_context *ndev_ctx;
+	struct netvsc_device *net_device;
+
+	net_device =
+		(struct netvsc_device *)hv_get_drvdata(dev);
+	net = net_device->ndev;
 
 	if (net == NULL) {
 		dev_err(&dev->device, "No net device to remove\n");
diff --git a/drivers/staging/hv/rndis_filter.c b/drivers/staging/hv/rndis_filter.c
index b325345..79948be 100644
--- a/drivers/staging/hv/rndis_filter.c
+++ b/drivers/staging/hv/rndis_filter.c
@@ -141,7 +141,12 @@ static void put_rndis_request(struct rndis_device *dev,
 static void dump_rndis_message(struct hv_device *hv_dev,
 			struct rndis_message *rndis_msg)
 {
-	struct net_device *netdev = dev_get_drvdata(&hv_dev->device);
+	struct net_device *netdev;
+	struct netvsc_device *net_device;
+
+	net_device =
+		(struct netvsc_device *)hv_get_drvdata(hv_dev);
+	netdev = net_device->ndev;
 
 	switch (rndis_msg->ndis_msg_type) {
 	case REMOTE_NDIS_PACKET_MSG:
@@ -249,7 +254,9 @@ static void rndis_filter_receive_response(struct rndis_device *dev,
 	struct rndis_request *request = NULL;
 	bool found = false;
 	unsigned long flags;
-	struct net_device *ndev = dev_get_drvdata(&dev->net_dev->dev->device);
+	struct net_device *ndev;
+
+	ndev = dev->net_dev->ndev;
 
 	spin_lock_irqsave(&dev->request_lock, flags);
 	list_for_each_entry(request, &dev->req_list, list_ent) {
@@ -356,11 +363,17 @@ static void rndis_filter_receive_data(struct rndis_device *dev,
 int rndis_filter_receive(struct hv_device *dev,
 				struct hv_netvsc_packet	*pkt)
 {
-	struct netvsc_device *net_dev = dev->ext;
+	struct netvsc_device *net_dev =
+		(struct netvsc_device *)hv_get_drvdata(dev);
 	struct rndis_device *rndis_dev;
 	struct rndis_message rndis_msg;
 	struct rndis_message *rndis_hdr;
-	struct net_device *ndev = dev_get_drvdata(&dev->device);
+	struct net_device *ndev;
+	struct netvsc_device *net_device;
+
+	net_device =
+		(struct netvsc_device *)hv_get_drvdata(dev);
+	ndev = net_device->ndev;
 
 	if (!net_dev)
 		return -EINVAL;
@@ -517,7 +530,9 @@ static int rndis_filter_set_packet_filter(struct rndis_device *dev,
 	struct rndis_set_complete *set_complete;
 	u32 status;
 	int ret, t;
-	struct net_device *ndev = dev_get_drvdata(&dev->net_dev->dev->device);
+	struct net_device *ndev;
+
+	ndev = dev->net_dev->ndev;
 
 	request = get_rndis_request(dev, REMOTE_NDIS_SET_MSG,
 			RNDIS_MESSAGE_SIZE(struct rndis_set_request) +
@@ -700,7 +715,7 @@ int rndis_filter_device_add(struct hv_device *dev,
 
 
 	/* Initialize the rndis device */
-	netDevice = dev->ext;
+	netDevice = (struct netvsc_device *)hv_get_drvdata(dev);
 
 	netDevice->extension = rndisDevice;
 	rndisDevice->net_dev = netDevice;
@@ -737,7 +752,8 @@ int rndis_filter_device_add(struct hv_device *dev,
 
 void rndis_filter_device_remove(struct hv_device *dev)
 {
-	struct netvsc_device *net_dev = dev->ext;
+	struct netvsc_device *net_dev =
+		(struct netvsc_device *)hv_get_drvdata(dev);
 	struct rndis_device *rndis_dev = net_dev->extension;
 
 	/* Halt and release the rndis device */
@@ -752,7 +768,8 @@ void rndis_filter_device_remove(struct hv_device *dev)
 
 int rndis_filter_open(struct hv_device *dev)
 {
-	struct netvsc_device *netDevice = dev->ext;
+	struct netvsc_device *netDevice =
+		(struct netvsc_device *)hv_get_drvdata(dev);
 
 	if (!netDevice)
 		return -EINVAL;
@@ -762,7 +779,8 @@ int rndis_filter_open(struct hv_device *dev)
 
 int rndis_filter_close(struct hv_device *dev)
 {
-	struct netvsc_device *netDevice = dev->ext;
+	struct netvsc_device *netDevice =
+		(struct netvsc_device *)hv_get_drvdata(dev);
 
 	if (!netDevice)
 		return -EINVAL;
-- 
1.7.4.1