Drivers: hv: vmbus: Use all supported IC versions to negotiate

Previously, we were assuming that each IC protocol version was tied to a
specific host version. For example, some Windows 10 preview hosts only
support v3 TimeSync even though driver assumes v4 is supported by all
Windows 10 hosts.

The guest will stop trying to negotiate even though older supported
versions may still be offered by the host.

Make IC version negotiation more robust by going through all versions
that are supported by the guest.

Fixes: 3da0401b4d0e ("Drivers: hv: utils: Fix the mapping between host
version and protocol to use")

Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
Signed-off-by: Alex Ng <alexng@messages.microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 51 insertions, 43 deletions

diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
index 51528bf92777..891537ae579f 100644
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -58,7 +58,31 @@
 static int sd_srv_version;
 static int ts_srv_version;
 static int hb_srv_version;
-static int util_fw_version;
+
+#define SD_VER_COUNT 2
+static const int sd_versions[] = {
+	SD_VERSION,
+	SD_VERSION_1
+};
+
+#define TS_VER_COUNT 3
+static const int ts_versions[] = {
+	TS_VERSION,
+	TS_VERSION_3,
+	TS_VERSION_1
+};
+
+#define HB_VER_COUNT 2
+static const int hb_versions[] = {
+	HB_VERSION,
+	HB_VERSION_1
+};
+
+#define FW_VER_COUNT 2
+static const int fw_versions[] = {
+	UTIL_FW_VERSION,
+	UTIL_WS2K8_FW_VERSION
+};
 
 static void shutdown_onchannelcallback(void *context);
 static struct hv_util_service util_shutdown = {
@@ -119,7 +143,6 @@ static void shutdown_onchannelcallback(void *context)
 	struct shutdown_msg_data *shutdown_msg;
 
 	struct icmsg_hdr *icmsghdrp;
-	struct icmsg_negotiate *negop = NULL;
 
 	vmbus_recvpacket(channel, shut_txf_buf,
 			 PAGE_SIZE, &recvlen, &requestid);
@@ -129,9 +152,14 @@ static void shutdown_onchannelcallback(void *context)
 			sizeof(struct vmbuspipe_hdr)];
 
 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-			vmbus_prep_negotiate_resp(icmsghdrp, negop,
-					shut_txf_buf, util_fw_version,
-					sd_srv_version);
+			if (vmbus_prep_negotiate_resp(icmsghdrp, shut_txf_buf,
+					fw_versions, FW_VER_COUNT,
+					sd_versions, SD_VER_COUNT,
+					NULL, &sd_srv_version)) {
+				pr_info("Shutdown IC version %d.%d\n",
+					sd_srv_version >> 16,
+					sd_srv_version & 0xFFFF);
+			}
 		} else {
 			shutdown_msg =
 				(struct shutdown_msg_data *)&shut_txf_buf[
@@ -254,7 +282,6 @@ static void timesync_onchannelcallback(void *context)
 	struct ictimesync_data *timedatap;
 	struct ictimesync_ref_data *refdata;
 	u8 *time_txf_buf = util_timesynch.recv_buffer;
-	struct icmsg_negotiate *negop = NULL;
 
 	vmbus_recvpacket(channel, time_txf_buf,
 			 PAGE_SIZE, &recvlen, &requestid);
@@ -264,12 +291,14 @@ static void timesync_onchannelcallback(void *context)
 				sizeof(struct vmbuspipe_hdr)];
 
 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-			vmbus_prep_negotiate_resp(icmsghdrp, negop,
-						time_txf_buf,
-						util_fw_version,
-						ts_srv_version);
-			pr_info("Using TimeSync version %d.%d\n",
-				ts_srv_version >> 16, ts_srv_version & 0xFFFF);
+			if (vmbus_prep_negotiate_resp(icmsghdrp, time_txf_buf,
+						fw_versions, FW_VER_COUNT,
+						ts_versions, TS_VER_COUNT,
+						NULL, &ts_srv_version)) {
+				pr_info("TimeSync version %d.%d\n",
+					ts_srv_version >> 16,
+					ts_srv_version & 0xFFFF);
+			}
 		} else {
 			if (ts_srv_version > TS_VERSION_3) {
 				refdata = (struct ictimesync_ref_data *)
@@ -313,7 +342,6 @@ static void heartbeat_onchannelcallback(void *context)
 	struct icmsg_hdr *icmsghdrp;
 	struct heartbeat_msg_data *heartbeat_msg;
 	u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
-	struct icmsg_negotiate *negop = NULL;
 
 	while (1) {
 
@@ -327,9 +355,16 @@ static void heartbeat_onchannelcallback(void *context)
 				sizeof(struct vmbuspipe_hdr)];
 
 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
-			vmbus_prep_negotiate_resp(icmsghdrp, negop,
-				hbeat_txf_buf, util_fw_version,
-				hb_srv_version);
+			if (vmbus_prep_negotiate_resp(icmsghdrp,
+					hbeat_txf_buf,
+					fw_versions, FW_VER_COUNT,
+					hb_versions, HB_VER_COUNT,
+					NULL, &hb_srv_version)) {
+
+				pr_info("Heartbeat version %d.%d\n",
+					hb_srv_version >> 16,
+					hb_srv_version & 0xFFFF);
+			}
 		} else {
 			heartbeat_msg =
 				(struct heartbeat_msg_data *)&hbeat_txf_buf[
@@ -379,33 +414,6 @@ static int util_probe(struct hv_device *dev,
 
 	hv_set_drvdata(dev, srv);
 
-	/*
-	 * Based on the host; initialize the framework and
-	 * service version numbers we will negotiate.
-	 */
-	switch (vmbus_proto_version) {
-	case (VERSION_WS2008):
-		util_fw_version = UTIL_WS2K8_FW_VERSION;
-		sd_srv_version = SD_VERSION_1;
-		ts_srv_version = TS_VERSION_1;
-		hb_srv_version = HB_VERSION_1;
-		break;
-	case VERSION_WIN7:
-	case VERSION_WIN8:
-	case VERSION_WIN8_1:
-		util_fw_version = UTIL_FW_VERSION;
-		sd_srv_version = SD_VERSION;
-		ts_srv_version = TS_VERSION_3;
-		hb_srv_version = HB_VERSION;
-		break;
-	case VERSION_WIN10:
-	default:
-		util_fw_version = UTIL_FW_VERSION;
-		sd_srv_version = SD_VERSION;
-		ts_srv_version = TS_VERSION;
-		hb_srv_version = HB_VERSION;
-	}
-
 	ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
 			srv->util_cb, dev->channel);
 	if (ret)