Commit 0cf73780 authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by David S. Miller
Browse files

hv_netvsc: netvsc_teardown_gpadl() split 



It was found that in some cases host refuses to teardown GPADL for send/
receive buffers (probably when some work with these buffere is scheduled or
ongoing). Change the teardown logic to be:
1) Send NVSP_MSG1_TYPE_REVOKE_* messages
2) Close the channel
3) Teardown GPADLs.
This seems to work reliably.

Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3928ee64

drivers/net/hyperv/netvsc.c

+36 −33
Original line number Diff line number Diff line
@@ -100,12 +100,11 @@ static void free_netvsc_device_rcu(struct netvsc_device *nvdev) 
	call_rcu(&nvdev->rcu, free_netvsc_device);

}



static void netvsc_destroy_buf(struct hv_device *device)

static void netvsc_revoke_buf(struct hv_device *device,

			      struct netvsc_device *net_device)

{

	struct nvsp_message *revoke_packet;

	struct net_device *ndev = hv_get_drvdata(device);

	struct net_device_context *ndc = netdev_priv(ndev);

	struct netvsc_device *net_device = rtnl_dereference(ndc->nvdev);

	int ret;



	/*
@@ -148,28 +147,6 @@ static void netvsc_destroy_buf(struct hv_device *device) 
		net_device->recv_section_cnt = 0;

	}



	/* Teardown the gpadl on the vsp end */

	if (net_device->recv_buf_gpadl_handle) {

		ret = vmbus_teardown_gpadl(device->channel,

					   net_device->recv_buf_gpadl_handle);



		/* If we failed here, we might as well return and have a leak

		 * rather than continue and a bugchk

		 */

		if (ret != 0) {

			netdev_err(ndev,

				   "unable to teardown receive buffer's gpadl\n");

			return;

		}

		net_device->recv_buf_gpadl_handle = 0;

	}



	if (net_device->recv_buf) {

		/* Free up the receive buffer */

		vfree(net_device->recv_buf);

		net_device->recv_buf = NULL;

	}



	/* Deal with the send buffer we may have setup.

	 * If we got a  send section size, it means we received a

	 * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
@@ -210,7 +187,35 @@ static void netvsc_destroy_buf(struct hv_device *device) 
		}

		net_device->send_section_cnt = 0;

	}

	/* Teardown the gpadl on the vsp end */

}



static void netvsc_teardown_gpadl(struct hv_device *device,

				  struct netvsc_device *net_device)

{

	struct net_device *ndev = hv_get_drvdata(device);

	int ret;



	if (net_device->recv_buf_gpadl_handle) {

		ret = vmbus_teardown_gpadl(device->channel,

					   net_device->recv_buf_gpadl_handle);



		/* If we failed here, we might as well return and have a leak

		 * rather than continue and a bugchk

		 */

		if (ret != 0) {

			netdev_err(ndev,

				   "unable to teardown receive buffer's gpadl\n");

			return;

		}

		net_device->recv_buf_gpadl_handle = 0;

	}



	if (net_device->recv_buf) {

		/* Free up the receive buffer */

		vfree(net_device->recv_buf);

		net_device->recv_buf = NULL;

	}



	if (net_device->send_buf_gpadl_handle) {

		ret = vmbus_teardown_gpadl(device->channel,

					   net_device->send_buf_gpadl_handle);
@@ -420,7 +425,8 @@ static int netvsc_init_buf(struct hv_device *device, 
	goto exit;



cleanup:

	netvsc_destroy_buf(device);

	netvsc_revoke_buf(device, net_device);

	netvsc_teardown_gpadl(device, net_device);



exit:

	return ret;
@@ -539,11 +545,6 @@ cleanup: 
	return ret;

}



static void netvsc_disconnect_vsp(struct hv_device *device)

{

	netvsc_destroy_buf(device);

}



/*

 * netvsc_device_remove - Callback when the root bus device is removed

 */
@@ -557,7 +558,7 @@ void netvsc_device_remove(struct hv_device *device) 


	cancel_work_sync(&net_device->subchan_work);



	netvsc_disconnect_vsp(device);

	netvsc_revoke_buf(device, net_device);



	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
@@ -570,6 +571,8 @@ void netvsc_device_remove(struct hv_device *device) 
	/* Now, we can close the channel safely */

	vmbus_close(device->channel);



	netvsc_teardown_gpadl(device, net_device);



	/* And dissassociate NAPI context from device */

	for (i = 0; i < net_device->num_chn; i++)

		netif_napi_del(&net_device->chan_table[i].napi);

CRA Git | Maintained and supported by SUSTech CRA and CCSE