Merge branch 'netvsc-small-cleanups'

Stephen Hemminger says:

====================
netvsc: small cleanups

These are all small optimizations found during development of later features.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/hyperv/hyperv_net.h

@@ -763,8 +763,7 @@ struct netvsc_device {
 
 	refcount_t sc_offered;
 
-	/* Holds rndis device info */
-	void *extension;
+	struct rndis_device *extension;
 
 	int ring_size;
 

drivers/net/hyperv/netvsc.c

@@ -97,16 +97,6 @@ static void free_netvsc_device_rcu(struct netvsc_device *nvdev)
 	call_rcu(&nvdev->rcu, free_netvsc_device);
 }
 
-static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
-{
-	struct netvsc_device *net_device = hv_device_to_netvsc_device(device);
-
-	if (net_device && net_device->destroy)
-		net_device = NULL;
-
-	return net_device;
-}
-
 static void netvsc_destroy_buf(struct hv_device *device)
 {
 	struct nvsp_message *revoke_packet;
@@ -243,18 +233,15 @@ static void netvsc_destroy_buf(struct hv_device *device)
 	kfree(net_device->send_section_map);
 }
 
-static int netvsc_init_buf(struct hv_device *device)
+static int netvsc_init_buf(struct hv_device *device,
+			   struct netvsc_device *net_device)
 {
 	int ret = 0;
-	struct netvsc_device *net_device;
 	struct nvsp_message *init_packet;
 	struct net_device *ndev;
 	size_t map_words;
 	int node;
 
-	net_device = get_outbound_net_device(device);
-	if (!net_device)
-		return -ENODEV;
 	ndev = hv_get_drvdata(device);
 
 	node = cpu_to_node(device->channel->target_cpu);
@@ -285,9 +272,7 @@ static int netvsc_init_buf(struct hv_device *device)
 
 	/* Notify the NetVsp of the gpadl handle */
 	init_packet = &net_device->channel_init_pkt;
-
 	memset(init_packet, 0, sizeof(struct nvsp_message));
-
 	init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 	init_packet->msg.v1_msg.send_recv_buf.
 		gpadl_handle = net_device->recv_buf_gpadl_handle;
@@ -486,20 +471,15 @@ static int negotiate_nvsp_ver(struct hv_device *device,
 	return ret;
 }
 
-static int netvsc_connect_vsp(struct hv_device *device)
+static int netvsc_connect_vsp(struct hv_device *device,
+			      struct netvsc_device *net_device)
 {
-	int ret;
-	struct netvsc_device *net_device;
-	struct nvsp_message *init_packet;
-	int ndis_version;
 	const u32 ver_list[] = {
 		NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
-		NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5 };
-	int i;
-
-	net_device = get_outbound_net_device(device);
-	if (!net_device)
-		return -ENODEV;
+		NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5
+	};
+	struct nvsp_message *init_packet;
+	int ndis_version, i, ret;
 
 	init_packet = &net_device->channel_init_pkt;
 
@@ -549,7 +529,7 @@ static int netvsc_connect_vsp(struct hv_device *device)
 		net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 	net_device->send_buf_size = NETVSC_SEND_BUFFER_SIZE;
 
-	ret = netvsc_init_buf(device);
+	ret = netvsc_init_buf(device, net_device);
 
 cleanup:
 	return ret;
@@ -843,7 +823,7 @@ int netvsc_send(struct hv_device *device,
 		struct hv_page_buffer **pb,
 		struct sk_buff *skb)
 {
-	struct netvsc_device *net_device;
+	struct netvsc_device *net_device = hv_device_to_netvsc_device(device);
 	int ret = 0;
 	struct netvsc_channel *nvchan;
 	u32 pktlen = packet->total_data_buflen, msd_len = 0;
@@ -854,15 +834,15 @@ int netvsc_send(struct hv_device *device,
 	bool try_batch;
 	bool xmit_more = (skb != NULL) ? skb->xmit_more : false;
 
-	net_device = get_outbound_net_device(device);
-	if (!net_device)
+	/* If device is rescinded, return error and packet will get dropped. */
+	if (unlikely(net_device->destroy))
 		return -ENODEV;
 
 	/* We may race with netvsc_connect_vsp()/netvsc_init_buf() and get
 	 * here before the negotiation with the host is finished and
 	 * send_section_map may not be allocated yet.
 	 */
-	if (!net_device->send_section_map)
+	if (unlikely(!net_device->send_section_map))
 		return -EAGAIN;
 
 	nvchan = &net_device->chan_table[packet->q_idx];
@@ -1349,7 +1329,7 @@ int netvsc_device_add(struct hv_device *device,
 	rcu_assign_pointer(net_device_ctx->nvdev, net_device);
 
 	/* Connect with the NetVsp */
-	ret = netvsc_connect_vsp(device);
+	ret = netvsc_connect_vsp(device, net_device);
 	if (ret != 0) {
 		netdev_err(ndev,
 			"unable to connect to NetVSP - %d\n", ret);
@@ -1368,4 +1348,5 @@ int netvsc_device_add(struct hv_device *device,
 	free_netvsc_device(&net_device->rcu);
 
 	return ret;
+
 }

drivers/net/hyperv/netvsc_drv.c

@@ -120,7 +120,7 @@ static int netvsc_close(struct net_device *net)
 	struct net_device_context *net_device_ctx = netdev_priv(net);
 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 	int ret;
-	u32 aread, awrite, i, msec = 10, retry = 0, retry_max = 20;
+	u32 aread, i, msec = 10, retry = 0, retry_max = 20;
 	struct vmbus_channel *chn;
 
 	netif_tx_disable(net);
@@ -141,15 +141,11 @@ static int netvsc_close(struct net_device *net)
 			if (!chn)
 				continue;
 
-			hv_get_ringbuffer_availbytes(&chn->inbound, &aread,
-						     &awrite);
-
+			aread = hv_get_bytes_to_read(&chn->inbound);
 			if (aread)
 				break;
 
-			hv_get_ringbuffer_availbytes(&chn->outbound, &aread,
-						     &awrite);
-
+			aread = hv_get_bytes_to_read(&chn->outbound);
 			if (aread)
 				break;
 		}
@@ -345,34 +341,14 @@ static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
 	return slots_used;
 }
 
-static int count_skb_frag_slots(struct sk_buff *skb)
-{
-	int i, frags = skb_shinfo(skb)->nr_frags;
-	int pages = 0;
-
-	for (i = 0; i < frags; i++) {
-		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
-		unsigned long size = skb_frag_size(frag);
-		unsigned long offset = frag->page_offset;
-
-		/* Skip unused frames from start of page */
-		offset &= ~PAGE_MASK;
-		pages += PFN_UP(offset + size);
-	}
-	return pages;
-}
-
-static int netvsc_get_slots(struct sk_buff *skb)
+/* Estimate number of page buffers neede to transmit
+ * Need at most 2 for RNDIS header plus skb body and fragments.
+ */
+static unsigned int netvsc_get_slots(const struct sk_buff *skb)
 {
-	char *data = skb->data;
-	unsigned int offset = offset_in_page(data);
-	unsigned int len = skb_headlen(skb);
-	int slots;
-	int frag_slots;
-
-	slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
-	frag_slots = count_skb_frag_slots(skb);
-	return slots + frag_slots;
+	return PFN_UP(offset_in_page(skb->data) + skb_headlen(skb))
+		+ skb_shinfo(skb)->nr_frags
+		+ 2;
 }
 
 static u32 net_checksum_info(struct sk_buff *skb)
@@ -410,21 +386,18 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 	struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT];
 	struct hv_page_buffer *pb = page_buf;
 
-	/* We will atmost need two pages to describe the rndis
-	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
+	/* We can only transmit MAX_PAGE_BUFFER_COUNT number
 	 * of pages in a single packet. If skb is scattered around
 	 * more pages we try linearizing it.
 	 */
-
-	num_data_pgs = netvsc_get_slots(skb) + 2;
-
+	num_data_pgs = netvsc_get_slots(skb);
 	if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) {
 		++net_device_ctx->eth_stats.tx_scattered;
 
 		if (skb_linearize(skb))
 			goto no_memory;
 
-		num_data_pgs = netvsc_get_slots(skb) + 2;
+		num_data_pgs = netvsc_get_slots(skb);
 		if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
 			++net_device_ctx->eth_stats.tx_too_big;
 			goto drop;