storvsc: Refactor the code in storvsc_channel_init()

The function storvsc_channel_init() repeatedly interacts with the host
to extract various channel properties. Refactor this code to eliminate
code repetition.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Long Li <longli@microsoft.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index cfbb2890b31f255c15398b6ec80c957f82195886..811f276baed836e263ccf312a4f63c9b8e69a64f 100644 (file)
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -723,29 +723,17 @@ static void cache_wwn(struct storvsc_device *stor_device,
        }
 }
 
-static int storvsc_channel_init(struct hv_device *device, bool is_fc)
+
+static int storvsc_execute_vstor_op(struct hv_device *device,
+                                   struct storvsc_cmd_request *request,
+                                   bool status_check)
 {
-       struct storvsc_device *stor_device;
-       struct storvsc_cmd_request *request;
        struct vstor_packet *vstor_packet;
-       int ret, t, i;
-       int max_chns;
-       bool process_sub_channels = false;
-
-       stor_device = get_out_stor_device(device);
-       if (!stor_device)
-               return -ENODEV;
+       int ret, t;
 
-       request = &stor_device->init_request;
        vstor_packet = &request->vstor_packet;
 
-       /*
-        * Now, initiate the vsc/vsp initialization protocol on the open
-        * channel
-        */
-       memset(request, 0, sizeof(struct storvsc_cmd_request));
        init_completion(&request->wait_event);
-       vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
        vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 
        ret = vmbus_sendpacket(device->channel, vstor_packet,
@@ -761,17 +749,50 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
        if (t == 0)
                return -ETIMEDOUT;
 
+       if (!status_check)
+               return ret;
+
        if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
            vstor_packet->status != 0)
                return -EINVAL;
 
+       return ret;
+}
+
+static int storvsc_channel_init(struct hv_device *device, bool is_fc)
+{
+       struct storvsc_device *stor_device;
+       struct storvsc_cmd_request *request;
+       struct vstor_packet *vstor_packet;
+       int ret, i;
+       int max_chns;
+       bool process_sub_channels = false;
+
+       stor_device = get_out_stor_device(device);
+       if (!stor_device)
+               return -ENODEV;
+
+       request = &stor_device->init_request;
+       vstor_packet = &request->vstor_packet;
+
+       /*
+        * Now, initiate the vsc/vsp initialization protocol on the open
+        * channel
+        */
+       memset(request, 0, sizeof(struct storvsc_cmd_request));
+       vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
+       ret = storvsc_execute_vstor_op(device, request, true);
+       if (ret)
+               return ret;
+       /*
+        * Query host supported protocol version.
+        */
 
        for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
                /* reuse the packet for version range supported */
                memset(vstor_packet, 0, sizeof(struct vstor_packet));
                vstor_packet->operation =
                        VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
-               vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 
                vstor_packet->version.major_minor =
                        vmstor_protocols[i].protocol_version;
@@ -780,20 +801,10 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
                 * The revision number is only used in Windows; set it to 0.
                 */
                vstor_packet->version.revision = 0;
-
-               ret = vmbus_sendpacket(device->channel, vstor_packet,
-                              (sizeof(struct vstor_packet) -
-                               vmscsi_size_delta),
-                              (unsigned long)request,
-                              VM_PKT_DATA_INBAND,
-                              VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+               ret = storvsc_execute_vstor_op(device, request, false);
                if (ret != 0)
                        return ret;
 
-               t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
-               if (t == 0)
-                       return -ETIMEDOUT;
-
                if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
                        return -EINVAL;
 
@@ -817,26 +828,10 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
 
        memset(vstor_packet, 0, sizeof(struct vstor_packet));
        vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
-       vstor_packet->flags = REQUEST_COMPLETION_FLAG;
-
-       ret = vmbus_sendpacket(device->channel, vstor_packet,
-                              (sizeof(struct vstor_packet) -
-                               vmscsi_size_delta),
-                              (unsigned long)request,
-                              VM_PKT_DATA_INBAND,
-                              VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
-
+       ret = storvsc_execute_vstor_op(device, request, true);
        if (ret != 0)
                return ret;
 
-       t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
-       if (t == 0)
-               return -ETIMEDOUT;
-
-       if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
-           vstor_packet->status != 0)
-               return -EINVAL;
-
        /*
         * Check to see if multi-channel support is there.
         * Hosts that implement protocol version of 5.1 and above
@@ -854,28 +849,15 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
        if (!is_fc)
                goto done;
 
+       /*
+        * For FC devices retrieve FC HBA data.
+        */
        memset(vstor_packet, 0, sizeof(struct vstor_packet));
        vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
-       vstor_packet->flags = REQUEST_COMPLETION_FLAG;
-
-       ret = vmbus_sendpacket(device->channel, vstor_packet,
-                              (sizeof(struct vstor_packet) -
-                              vmscsi_size_delta),
-                              (unsigned long)request,
-                              VM_PKT_DATA_INBAND,
-                              VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
-
+       ret = storvsc_execute_vstor_op(device, request, true);
        if (ret != 0)
                return ret;
 
-       t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
-       if (t == 0)
-               return -ETIMEDOUT;
-
-       if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
-           vstor_packet->status != 0)
-               return -EINVAL;
-
        /*
         * Cache the currently active port and node ww names.
         */
@@ -885,26 +867,10 @@ done:
 
        memset(vstor_packet, 0, sizeof(struct vstor_packet));
        vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
-       vstor_packet->flags = REQUEST_COMPLETION_FLAG;
-
-       ret = vmbus_sendpacket(device->channel, vstor_packet,
-                              (sizeof(struct vstor_packet) -
-                               vmscsi_size_delta),
-                              (unsigned long)request,
-                              VM_PKT_DATA_INBAND,
-                              VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
-
+       ret = storvsc_execute_vstor_op(device, request, true);
        if (ret != 0)
                return ret;
 
-       t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
-       if (t == 0)
-               return -ETIMEDOUT;
-
-       if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
-           vstor_packet->status != 0)
-               return -EINVAL;
-
        if (process_sub_channels)
                handle_multichannel_storage(device, max_chns);