Drivers: hv: fcopy: full handshake support
Introduce FCOPY_VERSION_1 to support kernel replying to the negotiation
message with its own version.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Tested-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c
index 6a8ec9f..b7b528c 100644
--- a/drivers/hv/hv_fcopy.c
+++ b/drivers/hv/hv_fcopy.c
@@ -62,6 +62,10 @@
static const char fcopy_devname[] = "vmbus/hv_fcopy";
static u8 *recv_buffer;
static struct hvutil_transport *hvt;
+/*
+ * This state maintains the version number registered by the daemon.
+ */
+static int dm_reg_value;
static void fcopy_timeout_func(struct work_struct *dummy)
{
@@ -81,8 +85,18 @@
static int fcopy_handle_handshake(u32 version)
{
+ u32 our_ver = FCOPY_CURRENT_VERSION;
+
switch (version) {
- case FCOPY_CURRENT_VERSION:
+ case FCOPY_VERSION_0:
+ /* Daemon doesn't expect us to reply */
+ dm_reg_value = version;
+ break;
+ case FCOPY_VERSION_1:
+ /* Daemon expects us to reply with our own version */
+ if (hvutil_transport_send(hvt, &our_ver, sizeof(our_ver)))
+ return -EFAULT;
+ dm_reg_value = version;
break;
default:
/*