qga-win: refactor disk properties (bus)

Refactor code that queries bus type to be more generic. The function
get_disk_bus_type() has been renamed to build_guest_disk_info().
Following commit(s) will extend this function.

Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

qga/commands-win32.c

@@ -613,25 +613,28 @@ out:
     return pci;
 }
 
-static int get_disk_bus_type(HANDLE vol_h, Error **errp)
+static void get_disk_properties(HANDLE vol_h, GuestDiskAddress *disk,
+    Error **errp)
 {
     STORAGE_PROPERTY_QUERY query;
     STORAGE_DEVICE_DESCRIPTOR *dev_desc, buf;
     DWORD received;
+    ULONG size = sizeof(buf);
 
     dev_desc = &buf;
-    dev_desc->Size = sizeof(buf);
     query.PropertyId = StorageDeviceProperty;
     query.QueryType = PropertyStandardQuery;
 
     if (!DeviceIoControl(vol_h, IOCTL_STORAGE_QUERY_PROPERTY, &query,
                          sizeof(STORAGE_PROPERTY_QUERY), dev_desc,
-                         dev_desc->Size, &received, NULL)) {
+                         size, &received, NULL)) {
         error_setg_win32(errp, GetLastError(), "failed to get bus type");
-        return -1;
+        return;
     }
+    disk->bus_type = find_bus_type(dev_desc->BusType);
+    g_debug("bus type %d", disk->bus_type);
 
-    return dev_desc->BusType;
+    return;
 }
 
 /* VSS provider works with volumes, thus there is no difference if
@@ -643,7 +646,6 @@ static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
     GuestDiskAddress *disk;
     SCSI_ADDRESS addr, *scsi_ad;
     DWORD len;
-    int bus;
     HANDLE vol_h;
     Error *local_err = NULL;
 
@@ -655,17 +657,16 @@ static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
                        0, NULL);
     if (vol_h == INVALID_HANDLE_VALUE) {
         error_setg_win32(errp, GetLastError(), "failed to open volume");
-        goto out_free;
+        goto err;
-    }
-
-    g_debug("getting bus type");
-    bus = get_disk_bus_type(vol_h, errp);
-    if (bus < 0) {
-        goto out_close;
     }
 
     disk = g_malloc0(sizeof(*disk));
-    disk->bus_type = find_bus_type(bus);
+    get_disk_properties(vol_h, disk, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto err_close;
+    }
+
     g_debug("bus type %d", disk->bus_type);
     /* always set pci_controller as required by schema. get_pci_info() should
      * report -1 values for non-PCI buses rather than fail. fail the command
@@ -675,12 +676,14 @@ static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
     disk->pci_controller = get_pci_info(name, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
-        goto out_close;
+        goto err_close;
     }
-    if (bus == BusTypeScsi || bus == BusTypeAta || bus == BusTypeRAID
+    if (disk->bus_type == GUEST_DISK_BUS_TYPE_SCSI
+            || disk->bus_type == GUEST_DISK_BUS_TYPE_IDE
+            || disk->bus_type == GUEST_DISK_BUS_TYPE_RAID
 #if (_WIN32_WINNT >= 0x0600)
             /* This bus type is not supported before Windows Server 2003 SP1 */
-            || bus == BusTypeSas
+            || disk->bus_type == GUEST_DISK_BUS_TYPE_SAS
 #endif
         ) {
         /* We are able to use the same ioctls for different bus types
@@ -700,11 +703,17 @@ static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
     list = g_malloc0(sizeof(*list));
     list->value = disk;
     list->next = NULL;
-out_close:
     CloseHandle(vol_h);
-out_free:
     g_free(name);
     return list;
+
+err_close:
+    g_free(disk);
+    CloseHandle(vol_h);
+err:
+    g_free(name);
+
+    return NULL;
 }
 
 #else