[PATCH 2/2] hv: handle skb allocation failure

[PATCH 2/2] hv: handle skb allocation failure

[Stephen Hemminger]

Some fixes to receive handling:
  * Dieing with assertion failure when running out of memory is not ok
  * Use newer alloc function to get aligned skb
  * Dropped statistic is supposed to be incremented only by
    driver it was responsible for the drop.

Compile tested only.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

---
 drivers/staging/hv/netvsc_drv.c |   32 ++++++++++++--------------------
 1 file changed, 12 insertions(+), 20 deletions(-)

--- a/drivers/staging/hv/netvsc_drv.c	2010-03-09 17:27:57.263312289 -0800
+++ b/drivers/staging/hv/netvsc_drv.c	2010-03-09 17:34:45.012686682 -0800
@@ -292,7 +292,6 @@ static int netvsc_recv_callback(struct h
 	struct net_device_context *net_device_ctx;
 	struct sk_buff *skb;
 	void *data;
-	int ret;
 	int i;
 	unsigned long flags;
 
@@ -306,12 +305,12 @@ static int netvsc_recv_callback(struct h
 
 	net_device_ctx = netdev_priv(net);
 
-	/* Allocate a skb - TODO preallocate this */
-	/* Pad 2-bytes to align IP header to 16 bytes */
-	skb = dev_alloc_skb(packet->TotalDataBufferLength + 2);
-	ASSERT(skb);
-	skb_reserve(skb, 2);
-	skb->dev = net;
+	/* Allocate a skb - TODO direct I/O to pages? */
+	skb = netdev_alloc_skb_ip_align(net, packet->TotalDataBufferLength);
+	if (unlikely(!skb)) {
+		++net->stats.rx_dropped;
+		return 0;
+	}
 
 	/* for kmap_atomic */
 	local_irq_save(flags);
@@ -336,25 +335,18 @@ static int netvsc_recv_callback(struct h
 	local_irq_restore(flags);
 
 	skb->protocol = eth_type_trans(skb, net);
-
 	skb->ip_summed = CHECKSUM_NONE;
 
+	net->stats.rx_packets++;
+	net->stats.rx_bytes += skb->len;
+
 	/*
 	 * Pass the skb back up. Network stack will deallocate the skb when it
-	 * is done
+	 * is done.
+	 * TODO - use NAPI?
 	 */
-	ret = netif_rx(skb);
-
-	switch (ret) {
-	case NET_RX_DROP:
-		net->stats.rx_dropped++;
-		break;
-	default:
-		net->stats.rx_packets++;
-		net->stats.rx_bytes += skb->len;
-		break;
+	netif_rx(skb);
 
-	}
 	DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu",
 		   net->stats.rx_packets, net->stats.rx_bytes);
 

[PATCH 1/2] hv: use network device stats

[Stephen Hemminger]

The network device structure has space already reserved for statistics.

Compile tested only.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

---
 drivers/staging/hv/TODO         |    1 -
 drivers/staging/hv/netvsc_drv.c |   31 +++++++++----------------------
 2 files changed, 9 insertions(+), 23 deletions(-)

--- a/drivers/staging/hv/TODO	2010-03-09 17:07:51.483312299 -0800
+++ b/drivers/staging/hv/TODO	2010-03-09 17:08:05.812720241 -0800
@@ -9,7 +9,6 @@ TODO:
 	- see if the vmbus can be merged with the other virtual busses
 	  in the kernel
 	- audit the network driver
-	  - use existing net_device_stats struct in network device
 	  - checking for carrier inside open is wrong, network device API
             confusion??
 	- audit the block driver
--- a/drivers/staging/hv/netvsc_drv.c	2010-03-09 17:04:48.453624589 -0800
+++ b/drivers/staging/hv/netvsc_drv.c	2010-03-09 17:25:21.196552131 -0800
@@ -42,7 +42,6 @@
 struct net_device_context {
 	/* point back to our device context */
 	struct vm_device *device_ctx;
-	struct net_device_stats stats;
 };
 
 struct netvsc_driver_context {
@@ -57,13 +56,6 @@ static int netvsc_ringbuffer_size = NETV
 /* The one and only one */
 static struct netvsc_driver_context g_netvsc_drv;
 
-static struct net_device_stats *netvsc_get_stats(struct net_device *net)
-{
-	struct net_device_context *net_device_ctx = netdev_priv(net);
-
-	return &net_device_ctx->stats;
-}
-
 static void netvsc_set_multicast_list(struct net_device *net)
 {
 }
@@ -77,9 +69,6 @@ static int netvsc_open(struct net_device
 	DPRINT_ENTER(NETVSC_DRV);
 
 	if (netif_carrier_ok(net)) {
-		memset(&net_device_ctx->stats, 0,
-		       sizeof(struct net_device_stats));
-
 		/* Open up the device */
 		ret = RndisFilterOnOpen(device_obj);
 		if (ret != 0) {
@@ -223,8 +212,8 @@ retry_send:
 
 	if (ret == 0) {
 		ret = NETDEV_TX_OK;
-		net_device_ctx->stats.tx_bytes += skb->len;
-		net_device_ctx->stats.tx_packets++;
+		net->stats.tx_bytes += skb->len;
+		net->stats.tx_packets++;
 	} else {
 		retries++;
 		if (retries < 4) {
@@ -240,7 +229,7 @@ retry_send:
 		DPRINT_INFO(NETVSC_DRV, "net device (%p) stopping", net);
 
 		ret = NETDEV_TX_BUSY;
-		net_device_ctx->stats.tx_dropped++;
+		net->stats.tx_dropped++;
 
 		netif_stop_queue(net);
 
@@ -258,8 +247,8 @@ retry_send:
 	}
 
 	DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu",
-		   net_device_ctx->stats.tx_packets,
-		   net_device_ctx->stats.tx_bytes);
+		   net->stats.tx_packets,
+		   net->stats.tx_bytes);
 
 	DPRINT_EXIT(NETVSC_DRV);
 	return ret;
@@ -358,17 +347,16 @@ static int netvsc_recv_callback(struct h
 
 	switch (ret) {
 	case NET_RX_DROP:
-		net_device_ctx->stats.rx_dropped++;
+		net->stats.rx_dropped++;
 		break;
 	default:
-		net_device_ctx->stats.rx_packets++;
-		net_device_ctx->stats.rx_bytes += skb->len;
+		net->stats.rx_packets++;
+		net->stats.rx_bytes += skb->len;
 		break;
 
 	}
 	DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu",
-		   net_device_ctx->stats.rx_packets,
-		   net_device_ctx->stats.rx_bytes);
+		   net->stats.rx_packets, net->stats.rx_bytes);
 
 	DPRINT_EXIT(NETVSC_DRV);
 
@@ -379,7 +367,6 @@ static const struct net_device_ops devic
 	.ndo_open =			netvsc_open,
 	.ndo_stop =			netvsc_close,
 	.ndo_start_xmit =		netvsc_start_xmit,
-	.ndo_get_stats =		netvsc_get_stats,
 	.ndo_set_multicast_list =	netvsc_set_multicast_list,
 };
 

[PATCH] hv: name network device ethX rather than sethX

[Stephen Hemminger]

This patch makes the HyperV network device use the same naming
scheme as other virtual drivers (Xen, KVM). In an ideal world, 
userspace tools would not care what the name is, but some 
users and applications do care. Vyatta CLI is one of the tools
that does depend on what the name is.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
---
 drivers/staging/hv/netvsc_drv.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

--- a/drivers/staging/hv/netvsc_drv.c	2010-03-09 17:34:45.012686682 -0800
+++ b/drivers/staging/hv/netvsc_drv.c	2010-03-11 09:08:00.480877949 -0800
@@ -381,8 +381,7 @@ static int netvsc_probe(struct device *d
 	if (!net_drv_obj->Base.OnDeviceAdd)
 		return -1;
 
-	net = alloc_netdev(sizeof(struct net_device_context), "seth%d",
-			   ether_setup);
+	net = alloc_etherdev(sizeof(struct net_device_context));
 	if (!net)
 		return -1;