Drivers: scsi: storvsc: Fix a bug in handling VMBUS protocol version

Based on the negotiated VMBUS protocol version, we adjust the size of the storage
protocol messages. The two sizes we currently handle are pre-win8 and post-win8.
In WS2012 R2, we are negotiating higher VMBUS protocol version than the win8
version. Make adjustments to correctly handle this.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 8f8847ef110822a6536201c8c4db19afed20d5ad..7e8a642516817f4bc2b3f1fc658e47174b56363d 100644 (file)
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1752,19 +1752,22 @@ static int storvsc_probe(struct hv_device *device,
         * set state to properly communicate with the host.
         */
 
-       if (vmbus_proto_version == VERSION_WIN8) {
-               sense_buffer_size = POST_WIN7_STORVSC_SENSE_BUFFER_SIZE;
-               vmscsi_size_delta = 0;
-               vmstor_current_major = VMSTOR_WIN8_MAJOR;
-               vmstor_current_minor = VMSTOR_WIN8_MINOR;
-       } else {
+       switch (vmbus_proto_version) {
+       case VERSION_WS2008:
+       case VERSION_WIN7:
                sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE;
                vmscsi_size_delta = sizeof(struct vmscsi_win8_extension);
                vmstor_current_major = VMSTOR_WIN7_MAJOR;
                vmstor_current_minor = VMSTOR_WIN7_MINOR;
+               break;
+       default:
+               sense_buffer_size = POST_WIN7_STORVSC_SENSE_BUFFER_SIZE;
+               vmscsi_size_delta = 0;
+               vmstor_current_major = VMSTOR_WIN8_MAJOR;
+               vmstor_current_minor = VMSTOR_WIN8_MINOR;
+               break;
        }
 
-
        if (dev_id->driver_data == SFC_GUID)
                scsi_driver.can_queue = (STORVSC_MAX_IO_REQUESTS *
                                         STORVSC_FC_MAX_TARGETS);