Staging: hv: netvsc: Get rid of release_outbound_net_device() by inlining the code

Get rid of release_outbound_net_device() by inlining the code.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/hv/netvsc.c b/drivers/staging/hv/netvsc.c
index 67065c182b708d185f1f742bd039dbd7bf82c21c..e46161d05e6e6afc9378f75d14f804ae6600e10b 100644 (file)
--- a/drivers/staging/hv/netvsc.c
+++ b/drivers/staging/hv/netvsc.c
@@ -88,22 +88,6 @@ static void put_net_device(struct hv_device *device)
        atomic_dec(&net_device->refcnt);
 }
 
-static struct netvsc_device *release_outbound_net_device(
-               struct hv_device *device)
-{
-       struct netvsc_device *net_device;
-
-       net_device = device->ext;
-       if (net_device == NULL)
-               return NULL;
-
-       /* Busy wait until the ref drop to 2, then set it to 1 */
-       while (atomic_cmpxchg(&net_device->refcnt, 2, 1) != 2)
-               udelay(100);
-
-       return net_device;
-}
-
 static struct netvsc_device *release_inbound_net_device(
                struct hv_device *device)
 {
@@ -400,13 +384,8 @@ int netvsc_device_remove(struct hv_device *device)
        struct hv_netvsc_packet *netvsc_packet, *pos;
        unsigned long flags;
 
-       /* Stop outbound traffic ie sends and receives completions */
-       net_device = release_outbound_net_device(device);
-       if (!net_device) {
-               dev_err(&device->device, "No net device present!!");
-               return -ENODEV;
-       }
-
+       net_device = (struct netvsc_device *)device->ext;
+       atomic_dec(&net_device->refcnt);
        spin_lock_irqsave(&device->channel->inbound_lock, flags);
        net_device->destroy = true;
        spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
@@ -424,6 +403,18 @@ int netvsc_device_remove(struct hv_device *device)
        /* Stop inbound traffic ie receives and sends completions */
        net_device = release_inbound_net_device(device);
 
+       /*
+        * Wait until the ref cnt falls to 0.
+        * We have already stopped any new references
+        * for outgoing traffic. Also, at this point we don't have any
+        * incoming traffic as well. So this must be outgoing refrences
+        * established prior to marking the device as being destroyed.
+        * Since the send path is non-blocking, it is reasonable to busy
+        * wait here.
+        */
+       while (atomic_read(&net_device->refcnt))
+               udelay(100);
+
        /* At this point, no one should be accessing netDevice except in here */
        dev_notice(&device->device, "net device safe to remove");
 
@@ -976,7 +967,6 @@ cleanup:
                        kfree(packet);
                }
 
-               release_outbound_net_device(device);
                release_inbound_net_device(device);
 
                kfree(net_device);