qga: add implementation of guest-get-disks for Windows

The command lists all the physical disk drives. Unlike for Linux
partitions and virtual volumes are not listed.

Example output:

{
  "return": [
    {
      "name": "\\\\.\\PhysicalDrive0",
      "partition": false,
      "address": {
        "serial": "QM00001",
        "bus-type": "sata",
        ...
      },
      "dependents": []
    }
  ]
}

Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>

qga/commands-win32.c

@@ -979,6 +979,101 @@ out:
     return list;
 }
 
+GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
+{
+    ERRP_GUARD();
+    GuestDiskInfoList *new = NULL, *ret = NULL;
+    HDEVINFO dev_info;
+    SP_DEVICE_INTERFACE_DATA dev_iface_data;
+    int i;
+
+    dev_info = SetupDiGetClassDevs(&GUID_DEVINTERFACE_DISK, 0, 0,
+        DIGCF_PRESENT | DIGCF_DEVICEINTERFACE);
+    if (dev_info == INVALID_HANDLE_VALUE) {
+        error_setg_win32(errp, GetLastError(), "failed to get device tree");
+        return NULL;
+    }
+
+    g_debug("enumerating devices");
+    dev_iface_data.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA);
+    for (i = 0;
+        SetupDiEnumDeviceInterfaces(dev_info, NULL, &GUID_DEVINTERFACE_DISK,
+            i, &dev_iface_data);
+        i++) {
+        GuestDiskAddress *address = NULL;
+        GuestDiskInfo *disk = NULL;
+        Error *local_err = NULL;
+        g_autofree PSP_DEVICE_INTERFACE_DETAIL_DATA
+            pdev_iface_detail_data = NULL;
+        STORAGE_DEVICE_NUMBER sdn;
+        HANDLE dev_file;
+        DWORD size = 0;
+        BOOL result;
+        int attempt;
+
+        g_debug("  getting device path");
+        for (attempt = 0, result = FALSE; attempt < 2 && !result; attempt++) {
+            result = SetupDiGetDeviceInterfaceDetail(dev_info,
+                &dev_iface_data, pdev_iface_detail_data, size, &size, NULL);
+            if (result) {
+                break;
+            }
+            if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
+                pdev_iface_detail_data = g_realloc(pdev_iface_detail_data,
+                    size);
+                pdev_iface_detail_data->cbSize =
+                    sizeof(*pdev_iface_detail_data);
+            } else {
+                g_debug("failed to get device interface details");
+                break;
+            }
+        }
+        if (!result) {
+            g_debug("skipping device");
+            continue;
+        }
+
+        g_debug("  device: %s", pdev_iface_detail_data->DevicePath);
+        dev_file = CreateFile(pdev_iface_detail_data->DevicePath, 0,
+            FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
+        if (!DeviceIoControl(dev_file, IOCTL_STORAGE_GET_DEVICE_NUMBER,
+                NULL, 0, &sdn, sizeof(sdn), &size, NULL)) {
+            CloseHandle(dev_file);
+            debug_error("failed to get storage device number");
+            continue;
+        }
+        CloseHandle(dev_file);
+
+        disk = g_new0(GuestDiskInfo, 1);
+        disk->name = g_strdup_printf("\\\\.\\PhysicalDrive%lu",
+            sdn.DeviceNumber);
+
+        g_debug("  number: %lu", sdn.DeviceNumber);
+        address = g_malloc0(sizeof(GuestDiskAddress));
+        address->has_dev = true;
+        address->dev = g_strdup(disk->name);
+        get_single_disk_info(sdn.DeviceNumber, address, &local_err);
+        if (local_err) {
+            g_debug("failed to get disk info: %s",
+                error_get_pretty(local_err));
+            error_free(local_err);
+            qapi_free_GuestDiskAddress(address);
+            address = NULL;
+        } else {
+            disk->address = address;
+            disk->has_address = true;
+        }
+
+        new = g_malloc0(sizeof(GuestDiskInfoList));
+        new->value = disk;
+        new->next = ret;
+        ret = new;
+    }
+
+    SetupDiDestroyDeviceInfoList(dev_info);
+    return ret;
+}
+
 #else
 
 static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
@@ -986,6 +1081,12 @@ static GuestDiskAddressList *build_guest_disk_info(char *guid, Error **errp)
     return NULL;
 }
 
+GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
+{
+    error_setg(errp, QERR_UNSUPPORTED);
+    return NULL;
+}
+
 #endif /* CONFIG_QGA_NTDDSCSI */
 
 static GuestFilesystemInfo *build_guest_fsinfo(char *guid, Error **errp)
@@ -2458,9 +2559,3 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error **errp)
     }
     return head;
 }
-
-GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
-{
-    error_setg(errp, QERR_UNSUPPORTED);
-    return NULL;
-}