Drivers: net: hyperv: Cleanup the netvsc receive callback functio

Get rid of the buffer allocation in the receive path for normal packets.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 12 insertions, 23 deletions

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 7645ba38bde8..01a16ea77a5a 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -506,6 +506,8 @@ struct netvsc_device {
 
         /* Holds rndis device info */
         void *extension;
+        /* The recive buffer for this device */
+        unsigned char cb_buffer[NETVSC_PACKET_SIZE];
 };
 
 /* NdisInitialize message */
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 7fa2bbade327..9a0e9c6f1414 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -795,22 +795,16 @@ static void netvsc_channel_cb(void *context)
         struct netvsc_device *net_device;
         u32 bytes_recvd;
         u64 request_id;
-        unsigned char *packet;
         struct vmpacket_descriptor *desc;
         unsigned char *buffer;
         int bufferlen = NETVSC_PACKET_SIZE;
         struct net_device *ndev;
 
-        packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
-                         GFP_ATOMIC);
-        if (!packet)
-                return;
-        buffer = packet;
-
         net_device = get_inbound_net_device(device);
         if (!net_device)
-                goto out;
+                return;
         ndev = net_device->ndev;
+        buffer = net_device->cb_buffer;
 
         do {
                 ret = vmbus_recvpacket_raw(device->channel, buffer, bufferlen,
@@ -838,23 +832,16 @@ static void netvsc_channel_cb(void *context)
                                         break;
                                 }
 
-                                /* reset */
-                                if (bufferlen > NETVSC_PACKET_SIZE) {
-                                        kfree(buffer);
-                                        buffer = packet;
-                                        bufferlen = NETVSC_PACKET_SIZE;
-                                }
                         } else {
-                                /* reset */
-                                if (bufferlen > NETVSC_PACKET_SIZE) {
-                                        kfree(buffer);
-                                        buffer = packet;
-                                        bufferlen = NETVSC_PACKET_SIZE;
-                                }
-
+                                /*
+                                 * We are done for this pass.
+                                 */
                                 break;
                         }
+
                 } else if (ret == -ENOBUFS) {
+                        if (bufferlen > NETVSC_PACKET_SIZE)
+                                kfree(buffer);
                         /* Handle large packet */
                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
                         if (buffer == NULL) {
@@ -869,8 +856,8 @@ static void netvsc_channel_cb(void *context)
                 }
         } while (1);
 
-out:
-        kfree(buffer);
+        if (bufferlen > NETVSC_PACKET_SIZE)
+                kfree(buffer);
         return;
 }