X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=drivers%2Fhv%2Fhv_utils_transport.c;h=c235a95152671104cd7042a451b16ccd0d0d06ab;hb=c35bcfd8e4e11bdff2ffab823a13a59968426b15;hp=9a9983fa4531ad52a0f2918ffb51b42f9e8f2b89;hpb=c36581c9a536405a4bb56f88d8d7c55f93d73cd1;p=cascardo%2Flinux.git

diff --git a/drivers/hv/hv_utils_transport.c b/drivers/hv/hv_utils_transport.c
index 9a9983fa4531..c235a9515267 100644
--- a/drivers/hv/hv_utils_transport.c
+++ b/drivers/hv/hv_utils_transport.c
@@ -72,6 +72,10 @@ static ssize_t hvt_op_read(struct file *file, char __user *buf,
 	hvt->outmsg = NULL;
 	hvt->outmsg_len = 0;
 
+	if (hvt->on_read)
+		hvt->on_read();
+	hvt->on_read = NULL;
+
 out_unlock:
 	mutex_unlock(&hvt->lock);
 	return ret;
@@ -219,7 +223,8 @@ static void hvt_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
 	mutex_unlock(&hvt->lock);
 }
 
-int hvutil_transport_send(struct hvutil_transport *hvt, void *msg, int len)
+int hvutil_transport_send(struct hvutil_transport *hvt, void *msg, int len,
+			  void (*on_read_cb)(void))
 {
 	struct cn_msg *cn_msg;
 	int ret = 0;
@@ -237,6 +242,13 @@ int hvutil_transport_send(struct hvutil_transport *hvt, void *msg, int len)
 		memcpy(cn_msg->data, msg, len);
 		ret = cn_netlink_send(cn_msg, 0, 0, GFP_ATOMIC);
 		kfree(cn_msg);
+		/*
+		 * We don't know when netlink messages are delivered but unlike
+		 * in CHARDEV mode we're not blocked and we can send next
+		 * messages right away.
+		 */
+		if (on_read_cb)
+			on_read_cb();
 		return ret;
 	}
 	/* HVUTIL_TRANSPORT_CHARDEV */
@@ -255,6 +267,7 @@ int hvutil_transport_send(struct hvutil_transport *hvt, void *msg, int len)
 	if (hvt->outmsg) {
 		memcpy(hvt->outmsg, msg, len);
 		hvt->outmsg_len = len;
+		hvt->on_read = on_read_cb;
 		wake_up_interruptible(&hvt->outmsg_q);
 	} else
 		ret = -ENOMEM;