Re: [PATCH v6 2/2] xl: Add commands for usb hot-plug

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

On 04/24/2013 01:45 PM, Ian Campbell wrote:
> On Fri, 2013-04-19 at 16:59 +0100, George Dunlap wrote:
>> +
>> +int main_usb_attach(int argc, char **argv)
>> +{
>> +    uint32_t domid = INVALID_DOMID;
>> +    int opt = 0, rc;
>> +    char *device = NULL;
>> +
>> +    SWITCH_FOREACH_OPT(opt, "", NULL, "usb-attach", 2) {
>> +        /* No options */
>> +    }
>> +
>> +    domid = find_domain(argv[optind]);
>> +    device = argv[optind + 1];
>> +
>> +    if (domid == INVALID_DOMID) {
>> +        fprintf(stderr, "Must specify domid\n\n");
>> +        help("usb-attach");
>> +        return 2;
>> +    }
>
> find_domain won't return in this case, so no need to worry about it
> yourself.

I find that kind of scary, actually...

>
>> +int main_usb_detach(int argc, char **argv)
>> +{
>> +    uint32_t domid = INVALID_DOMID;
>> +    int opt = 0, rc;
>> +    char *device = NULL;
>> +    int type = 0;
>> +
>> +    SWITCH_FOREACH_OPT(opt, "", NULL, "usb-detach", 2) {
>> +        /* No options */
>> +    }
>> +
>> +    domid = find_domain(argv[optind]);
>> +    device = argv[optind + 1];
>> +
>> +    if (domid == INVALID_DOMID) {
>> +        fprintf(stderr, "Must specify domid\n\n");
>> +        help("usb-detach");
>> +        return 2;
>> +    }
>
>
> Same again.
>
>> +
>> +    rc = usb_detach(domid, type, device);
>> +    if (rc < 0)
>> +        return 1;
>> +    else
>> +        return 0;
>> +}
>> +
>> +static void usb_list(uint32_t domid)
>> +{
>> +    libxl_device_usb *dev;
>> +    int num, i;
>> +
>> +    dev = libxl_device_usb_list(ctx, domid, &num);
>> +    if (dev == NULL)
>> +        return;
>> +    printf("protocol  backend  type     device\n");
>> +    for (i = 0; i < num; i++) {
>> +        printf("%8s  ", (dev[i].protocol==LIBXL_USB_PROTOCOL_PV)?"pv":"dm");
>
> You can use libxl_usb_protocol_to_string here.

Could do, but I didn't necessarily want the long version ("devicemodel").

>
>> +        printf("%7d  ", dev[i].backend_domid);
>> +        printf("%7s  ", (dev[i].type==LIBXL_DEVICE_USB_TYPE_HOSTDEV)?"hostdev":"unknown");
>
> libxl_device_usb_type_to_string.

Will that print "unknown" in the case of unknown device types?

>
>> +        if (dev[i].type == LIBXL_DEVICE_USB_TYPE_HOSTDEV)
>> +            printf("%03d.%03d",
>> +                   dev[i].u.hostdev.hostbus,
>> +                   dev[i].u.hostdev.hostaddr);
>> +        printf("\n");
>> +    }
>> +    free(dev);
>
> You leak the content of the devices, you need to call
> libxl_device_usb_dispose on each, or better define
> libxl_device_usb_list_free (this is inconsistently provided by other
> devices, but may as well get it right for new code).

Ack.

  -George