Re: [PATCH RFC 0.2 2/2] xl: Add usb-add and usb-del commands

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

On 11/04/13 16:20, George Dunlap wrote:
> Add commands to add and remove host USB to HVM guests.
>
> WARNING: STILL A PROTOTYPE
>
> Signed-off-by: George Dunlap <george.dunlap@eu.citrix.com>
> ---
>   docs/man/xl.pod.1         |   51 ++++++++++++++++++++++
>   tools/libxl/xl.h          |    2 +
>   tools/libxl/xl_cmdimpl.c  |  105 +++++++++++++++++++++++++++++++++++++++++++++
>   tools/libxl/xl_cmdtable.c |    5 +++
>   4 files changed, 163 insertions(+)
>
> diff --git a/docs/man/xl.pod.1 b/docs/man/xl.pod.1
> index a0e298e..2b5e6d7 100644
> --- a/docs/man/xl.pod.1
> +++ b/docs/man/xl.pod.1
> @@ -1110,6 +1110,57 @@ List virtual network interfaces for a domain.
>   
>   =back
>   
> +=head2 HVM DEVICES
> +
> +=over 4
> +
> +=item B<hvm-host-usb-add> I<-d domain-id> I<-v host-device-spec> [I<-i devname>]

Hmm, it should be obvious that this bit is pure fiction... I'll of 
course fix it up before the final submission.

  -G

> +
> +Passes through the host USB device specified by I<host-device-spec> to the
> +HVM domain I<domain-id>.  Host-device-spec can be one of the following:
> +
> +=over 4
> +
> +=item <hostbus>.<hostaddr>
> +
> +=item <vendorid>:<productid>
> +
> +=item <hostbus>.<hostaddr>:<vendorid>:<productid>
> +
> +=back
> +
> +The best way to find out the information for the device is typically using
> +lsusb.
> +
> +Using the I<-i> option, you can specify a I<devname> for the
> +device. This is an arbitrary string that can be used by
> +I<hvm-host-usb-del> to remove the device later.  If no name is
> +specified, then one will be chosen automatically.  In any case the
> +devname will be printed to stdout if the device is successfully added.
> +
> +If the I<-i> option is used, then it must be used on device removal;
> +I<host-device-spec> cannot be used.
> +
> +This command is only available for domains using qemu-xen, not
> +qemu-traditional.
> +
> +=item B<hvm-host-usb-del> I<-d domain-id> (I<-i devname> | I<-v host-device-spec>)
> +
> +Remove the host USB device from I<domain-id> which is specified either
> +by I<devname> or I<host-device-spec>.  Exactly one of the two must be
> +specified.  I<devname> is a string that was specified when the device
> +was inserted by B<hvm-host-usb-add>.  I<host-device-spec> can only be
> +used if no name I<devname> was specified when the device was added,
> +and it must match exactly the specification given at that time.
> +
> +Devices specified in the config file do not have an associated
> +devname, and thus cannot be removed using this command.
> +
> +This command is only available for domains using qemu-xen, not
> +qemu-traditional.
> +
> +=back
> +
>   =head2 VTPM DEVICES
>   
>   =over 4
> diff --git a/tools/libxl/xl.h b/tools/libxl/xl.h
> index b881f92..1af0f3b 100644
> --- a/tools/libxl/xl.h
> +++ b/tools/libxl/xl.h
> @@ -35,6 +35,8 @@ int main_info(int argc, char **argv);
>   int main_sharing(int argc, char **argv);
>   int main_cd_eject(int argc, char **argv);
>   int main_cd_insert(int argc, char **argv);
> +int main_usb_add(int argc, char **argv);
> +int main_usb_del(int argc, char **argv);
>   int main_console(int argc, char **argv);
>   int main_vncviewer(int argc, char **argv);
>   int main_pcilist(int argc, char **argv);
> diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
> index 61f7b96..502a677 100644
> --- a/tools/libxl/xl_cmdimpl.c
> +++ b/tools/libxl/xl_cmdimpl.c
> @@ -2600,6 +2600,111 @@ int main_cd_insert(int argc, char **argv)
>       return 0;
>   }
>   
> +
> +
> +static int parse_usb_hostdev_specifier(libxl_device_usb *dev, const char *s)
> +{
> +    const char * hostbus, *hostaddr, *p;
> +
> +    hostbus = s;
> +    hostaddr=NULL;
> +
> +#define is_dec(_c) ((_c) >= '0' && (_c) <= '9')
> +#define is_hex(_c) (is_dec(_c) || ((_c) >= 'a' && (_c) <= 'f'))
> +
> +    /* Match [0-9]+\.[0-9] */
> +    if (!is_dec(*hostbus))
> +        return -1;
> +
> +    for(p=s; *p; p++) {
> +        if(*p == '.') {
> +            if ( !hostaddr )
> +                hostaddr = p+1;
> +            else {
> +                return -1;
> +            }
> +        } else if (!is_dec(*p)) {
> +            return -1;
> +        }
> +    }
> +    if (!hostaddr || !is_dec(*hostaddr))
> +        return -1;
> +    dev->u.hostdev.hostbus  = strtoul(hostbus,  NULL, 10);
> +    dev->u.hostdev.hostaddr = strtoul(hostaddr, NULL, 10);
> +#undef is_dec
> +#undef is_hex
> +
> +    return 0;
> +}
> +
> +static int usb_add(uint32_t domid, libxl_device_usb_type type,
> +                            const char * device)
> +{
> +    libxl_device_usb usbdev;
> +    int rc;
> +
> +    libxl_device_usb_init(&usbdev);
> +
> +    usbdev.type = type;
> +
> +    switch(type) {
> +    case LIBXL_DEVICE_USB_TYPE_HOSTDEV:
> +        if ( parse_usb_hostdev_specifier(&usbdev, device) < 0 ) {
> +            rc = ERROR_FAIL;
> +            goto out;
> +        }
> +        break;
> +    default:
> +        fprintf(stderr, "INTERNAL ERROR: Unimplemented type.\n");
> +        rc = ERROR_FAIL;
> +        goto out;
> +    }
> +
> +    if ( (rc = libxl_device_usb_add(ctx, domid, &usbdev, NULL)) < 0 )
> +        fprintf(stderr, "libxl_usb_add failed.\n");
> +
> +    libxl_device_usb_dispose(&usbdev);
> +
> +out:
> +    return rc;
> +}
> +
> +int main_usb_add(int argc, char **argv)
> +{
> +    uint32_t domid = -1;
> +    int opt = 0, rc;
> +    const char *device = NULL;
> +    int type = 0;
> +
> +    SWITCH_FOREACH_OPT(opt, "d:v:", NULL, "usb-add", 0) {
> +    case 'd':
> +        domid = find_domain(optarg);
> +        break;
> +    case 'v':
> +        type = LIBXL_DEVICE_USB_TYPE_HOSTDEV;
> +        device = optarg;
> +        break;
> +    }
> +
> +    if ( domid == -1 ) {
> +        fprintf(stderr, "Must specify domid\n\n");
> +        help("usb-add");
> +        return 2;
> +    }
> +
> +    if ( !device ) {
> +        fprintf(stderr, "Must specify a device\n\n");
> +        help("usb-add");
> +        return 2;
> +    }
> +
> +    rc = usb_add(domid, type, device);
> +    if ( rc < 0 )
> +        return 1;
> +    else
> +        return 0;
> +}
> +
>   int main_console(int argc, char **argv)
>   {
>       uint32_t domid;
> diff --git a/tools/libxl/xl_cmdtable.c b/tools/libxl/xl_cmdtable.c
> index b4a87ca..948dae1 100644
> --- a/tools/libxl/xl_cmdtable.c
> +++ b/tools/libxl/xl_cmdtable.c
> @@ -187,6 +187,11 @@ struct cmd_spec cmd_table[] = {
>         "Eject a cdrom from a guest's cd drive",
>         "<Domain> <VirtualDevice>",
>       },
> +    { "usb-add",
> +      &main_usb_add, 1, 1,
> +      "Hot-plug a usb device to a domain.",
> +      "-d <Domain> [-v <hostbus.hostaddr>]",
> +    },
>       { "mem-max",
>         &main_memmax, 0, 1,
>         "Set the maximum amount reservation for a domain",