[PATCH v2 2/3] Drivers: hv: vmbus: Enable VMBus protocol versions 4.1, 5.1 and 5.2

[Andrea Parri]

Hyper-V has added VMBus protocol versions 5.1 and 5.2 in recent release
versions.  Allow Linux guests to negotiate these new protocol versions
on versions of Hyper-V that support them.  While on this, also allow
guests to negotiate the VMBus protocol version 4.1 (which was missing).

Signed-off-by: Andrea Parri <parri.andrea@xxxxxxxxx>
---
 drivers/hv/connection.c          | 15 +++++++++------
 drivers/net/hyperv/netvsc.c      |  6 +++---
 include/linux/hyperv.h           |  8 +++++++-
 net/vmw_vsock/hyperv_transport.c |  4 ++--
 4 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index b1f805426e6b4..2f6961ac8c996 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -44,8 +44,11 @@ EXPORT_SYMBOL_GPL(vmbus_proto_version);
  * Table of VMBus versions listed from newest to oldest.
  */
 static __u32 vmbus_versions[] = {
+	VERSION_WIN10_V5_2,
+	VERSION_WIN10_V5_1,
 	VERSION_WIN10_V5,
-	VERSION_WIN10,
+	VERSION_WIN10_V4_1,
+	VERSION_WIN10_V4,
 	VERSION_WIN8_1,
 	VERSION_WIN8,
 	VERSION_WIN7,
@@ -68,12 +71,12 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version)
 	msg->vmbus_version_requested = version;
 
 	/*
-	 * VMBus protocol 5.0 (VERSION_WIN10_V5) requires that we must use
-	 * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message,
+	 * VMBus protocol 5.0 (VERSION_WIN10_V5) and higher require that we must
+	 * use VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message,
 	 * and for subsequent messages, we must use the Message Connection ID
 	 * field in the host-returned Version Response Message. And, with
-	 * VERSION_WIN10_V5, we don't use msg->interrupt_page, but we tell
-	 * the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for
+	 * VERSION_WIN10_V5 and higher, we don't use msg->interrupt_page, but we
+	 * tell the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for
 	 * compatibility.
 	 *
 	 * On old hosts, we should always use VMBUS_MESSAGE_CONNECTION_ID (1).
@@ -399,7 +402,7 @@ int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep)
 		case HV_STATUS_INVALID_CONNECTION_ID:
 			/*
 			 * See vmbus_negotiate_version(): VMBus protocol 5.0
-			 * requires that we must use
+			 * and higher require that we must use
 			 * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate
 			 * Contact message, but on old hosts that only
 			 * support VMBus protocol 4.0 or lower, here we get
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index d22a36fc7a7c6..d4c1a776b314a 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -624,11 +624,11 @@ void netvsc_device_remove(struct hv_device *device)
 	 * receive buffer GPADL. Do the same for send buffer.
 	 */
 	netvsc_revoke_recv_buf(device, net_device, ndev);
-	if (vmbus_proto_version < VERSION_WIN10)
+	if (vmbus_proto_version < VERSION_WIN10_V4)
 		netvsc_teardown_recv_gpadl(device, net_device, ndev);
 
 	netvsc_revoke_send_buf(device, net_device, ndev);
-	if (vmbus_proto_version < VERSION_WIN10)
+	if (vmbus_proto_version < VERSION_WIN10_V4)
 		netvsc_teardown_send_gpadl(device, net_device, ndev);
 
 	RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
@@ -650,7 +650,7 @@ void netvsc_device_remove(struct hv_device *device)
 	 * If host is Win2016 or higher then we do the GPADL tear down
 	 * here after VMBus is closed.
 	*/
-	if (vmbus_proto_version >= VERSION_WIN10) {
+	if (vmbus_proto_version >= VERSION_WIN10_V4) {
 		netvsc_teardown_recv_gpadl(device, net_device, ndev);
 		netvsc_teardown_send_gpadl(device, net_device, ndev);
 	}
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index c08b62dbd151f..a4f80e30b0207 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -182,15 +182,21 @@ static inline u32 hv_get_avail_to_write_percent(
  * 2 . 4  (Windows 8)
  * 3 . 0  (Windows 8 R2)
  * 4 . 0  (Windows 10)
+ * 4 . 1  (Windows 10 RS3)
  * 5 . 0  (Newer Windows 10)
+ * 5 . 1  (Windows 10 RS4)
+ * 5 . 2  (Windows Server 2019, RS5)
  */
 
 #define VERSION_WS2008  ((0 << 16) | (13))
 #define VERSION_WIN7    ((1 << 16) | (1))
 #define VERSION_WIN8    ((2 << 16) | (4))
 #define VERSION_WIN8_1    ((3 << 16) | (0))
-#define VERSION_WIN10	((4 << 16) | (0))
+#define VERSION_WIN10_V4 ((4 << 16) | (0))
+#define VERSION_WIN10_V4_1 ((4 << 16) | (1))
 #define VERSION_WIN10_V5 ((5 << 16) | (0))
+#define VERSION_WIN10_V5_1 ((5 << 16) | (1))
+#define VERSION_WIN10_V5_2 ((5 << 16) | (2))
 
 /* Make maximum size of pipe payload of 16K */
 #define MAX_PIPE_DATA_PAYLOAD		(sizeof(u8) * 16384)
diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
index c443db7af8d4a..cb0dbae4de14a 100644
--- a/net/vmw_vsock/hyperv_transport.c
+++ b/net/vmw_vsock/hyperv_transport.c
@@ -14,7 +14,7 @@
 #include <net/sock.h>
 #include <net/af_vsock.h>
 
-/* Older (VMBUS version 'VERSION_WIN10' or before) Windows hosts have some
+/* Older (VMBUS version 'VERSION_WIN10_V4' or before) Windows hosts have some
  * stricter requirements on the hv_sock ring buffer size of six 4K pages. Newer
  * hosts don't have this limitation; but, keep the defaults the same for compat.
  */
@@ -955,7 +955,7 @@ static int __init hvs_init(void)
 {
 	int ret;
 
-	if (vmbus_proto_version < VERSION_WIN10)
+	if (vmbus_proto_version < VERSION_WIN10_V4)
 		return -ENODEV;
 
 	ret = vmbus_driver_register(&hvs_drv);
-- 
2.23.0