src/patches/linux/0003-Drivers-net-hyperv-Cleanup-the-netvsc-receive-callba.patch

   1 From c9f2db35ac4f789930522d9d36200cb71b442bed Mon Sep 17 00:00:00 2001
   2 From: KY Srinivasan <kys@microsoft.com>
   3 Date: Sun, 16 Feb 2014 16:38:45 -0800
   4 Subject: [PATCH 03/25] Drivers: net: hyperv: Cleanup the netvsc receive
   5  callback functio
   6
   7 Get rid of the buffer allocation in the receive path for normal packets.
   8
   9 Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
  10 Signed-off-by: David S. Miller <davem@davemloft.net>
  11 ---
  12  drivers/net/hyperv/hyperv_net.h |  2 ++
  13  drivers/net/hyperv/netvsc.c     | 33 ++++++++++-----------------------
  14  2 files changed, 12 insertions(+), 23 deletions(-)
  15
  16 diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
  17 index 7645ba38bde8..01a16ea77a5a 100644
  18 --- a/drivers/net/hyperv/hyperv_net.h
  19 +++ b/drivers/net/hyperv/hyperv_net.h
  20 @@ -506,6 +506,8 @@ struct netvsc_device {
  21
  22         /* Holds rndis device info */
  23         void *extension;
  24 +       /* The recive buffer for this device */
  25 +       unsigned char cb_buffer[NETVSC_PACKET_SIZE];
  26  };
  27
  28  /* NdisInitialize message */
  29 diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
  30 index 7fa2bbade327..9a0e9c6f1414 100644
  31 --- a/drivers/net/hyperv/netvsc.c
  32 +++ b/drivers/net/hyperv/netvsc.c
  33 @@ -795,22 +795,16 @@ static void netvsc_channel_cb(void *context)
  34         struct netvsc_device *net_device;
  35         u32 bytes_recvd;
  36         u64 request_id;
  37 -       unsigned char *packet;
  38         struct vmpacket_descriptor *desc;
  39         unsigned char *buffer;
  40         int bufferlen = NETVSC_PACKET_SIZE;
  41         struct net_device *ndev;
  42
  43 -       packet = kzalloc(NETVSC_PACKET_SIZE * sizeof(unsigned char),
  44 -                        GFP_ATOMIC);
  45 -       if (!packet)
  46 -               return;
  47 -       buffer = packet;
  48 -
  49         net_device = get_inbound_net_device(device);
  50         if (!net_device)
  51 -               goto out;
  52 +               return;
  53         ndev = net_device->ndev;
  54 +       buffer = net_device->cb_buffer;
  55
  56         do {
  57                 ret = vmbus_recvpacket_raw(device->channel, buffer, bufferlen,
  58 @@ -838,23 +832,16 @@ static void netvsc_channel_cb(void *context)
  59                                         break;
  60                                 }
  61
  62 -                               /* reset */
  63 -                               if (bufferlen > NETVSC_PACKET_SIZE) {
  64 -                                       kfree(buffer);
  65 -                                       buffer = packet;
  66 -                                       bufferlen = NETVSC_PACKET_SIZE;
  67 -                               }
  68                         } else {
  69 -                               /* reset */
  70 -                               if (bufferlen > NETVSC_PACKET_SIZE) {
  71 -                                       kfree(buffer);
  72 -                                       buffer = packet;
  73 -                                       bufferlen = NETVSC_PACKET_SIZE;
  74 -                               }
  75 -
  76 +                               /*
  77 +                                * We are done for this pass.
  78 +                                */
  79                                 break;
  80                         }
  81 +
  82                 } else if (ret == -ENOBUFS) {
  83 +                       if (bufferlen > NETVSC_PACKET_SIZE)
  84 +                               kfree(buffer);
  85                         /* Handle large packet */
  86                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
  87                         if (buffer == NULL) {
  88 @@ -869,8 +856,8 @@ static void netvsc_channel_cb(void *context)
  89                 }
  90         } while (1);
  91
  92 -out:
  93 -       kfree(buffer);
  94 +       if (bufferlen > NETVSC_PACKET_SIZE)
  95 +               kfree(buffer);
  96         return;
  97  }
  98
  99 --
 100 2.4.3
 101