Re: [PATCH v6 1/2] libxl: Introduce functions to add and remove USB devices to an HVM guest

[George Dunlap <george.dunlap@eu.citrix.com>]

On 04/25/2013 03:19 PM, Anthony PERARD wrote:
> On 19/04/13 16:59, George Dunlap wrote:
>> diff --git a/tools/libxl/libxl_qmp.c b/tools/libxl/libxl_qmp.c
>> index 644d2c0..9ad3e59 100644
>> --- a/tools/libxl/libxl_qmp.c
>> +++ b/tools/libxl/libxl_qmp.c
>> @@ -42,6 +42,7 @@
>>
>>   #define QMP_RECEIVE_BUFFER_SIZE 4096
>>   #define PCI_PT_QDEV_ID "pci-pt-%02x_%02x.%01x"
>> +#define HOST_USB_QDEV_ID "usb-hostdev-%04x.%04x"
>>
>>   typedef int (*qmp_callback_t)(libxl__qmp_handler *qmp,
>>                                 const libxl__json_object *tree,
>> @@ -929,6 +930,70 @@ int libxl__qmp_insert_cdrom(libxl__gc *gc, int domid,
>>       }
>>   }
>>
>> +static int libxl__qmp_usb_hostdev_add(libxl__gc *gc, int domid,
>> +                                      libxl__device_usb *dev)
>> +{
>> +    libxl__json_object *args = NULL;
>> +    char *id;
>> +
>> +    id = GCSPRINTF(HOST_USB_QDEV_ID,
>> +                   (uint16_t)dev->u.hostdev.hostbus,
>> +                   (uint16_t)dev->u.hostdev.hostaddr);
>> +
>> +    qmp_parameters_add_string(gc, &args, "driver", "usb-host");
>> +    QMP_PARAMETERS_SPRINTF(&args, "hostbus", "0x%x",
> dev->u.hostdev.hostbus);
>> +    QMP_PARAMETERS_SPRINTF(&args, "hostaddr", "0x%x",
> dev->u.hostdev.hostaddr);
>> +
>> +    qmp_parameters_add_string(gc, &args, "id", id);
>
> You can use QMP_PARAMETERS_SPRINTF here instead of having a separate
> GCSPRINTF call. The former do the same call to sprintf as the later.

Ah, right -- another vestige of when I was passing the 'id' string back 
inside the device.

>
>> +
>> +    return qmp_run_command(gc, domid, "device_add", args, NULL, NULL);
>> +}
>> +
>> +int libxl__qmp_usb_add(libxl__gc *gc, int domid, libxl__device_usb
> *usbdev)
>> +{
>> +    int rc;
>> +    switch (usbdev->type) {
>> +    case LIBXL_DEVICE_USB_TYPE_HOSTDEV:
>> +        rc = libxl__qmp_usb_hostdev_add(gc, domid, usbdev);
>> +        break;
>> +    default:
>> +        return ERROR_INVAL;
>> +    }
>> +    return rc;
>> +}
>> +
>> +
>> +static int libxl__qmp_usb_hostdev_remove(libxl__gc *gc, int domid,
>> +                                         libxl__device_usb *dev)
>> +{
>> +    libxl__json_object *args = NULL;
>> +    char *id;
>> +
>> +    id = GCSPRINTF(HOST_USB_QDEV_ID,
>> +                   (uint16_t)dev->u.hostdev.hostbus,
>> +                   (uint16_t)dev->u.hostdev.hostaddr);
>> +
>> +    qmp_parameters_add_string(gc, &args, "id", id);
>> +
>> +    return qmp_run_command(gc, domid, "device_del", args, NULL, NULL);
>
> There is already a "device_del" which can be called:
> static int qmp_device_del(libxl__gc *gc, int domid, char *id);
>

Ack.

  -George