Re: [Qemu-devel] [PATCH v3] libxl: usb2 and usb3 controller support for upstream qemu

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

On 12/07/13 11:22, Fabio Fantoni wrote:
> Usage: usbversion=1|2|3 (default=2)
> Specifies the type of an emulated USB bus in the guest. 1 for usb1,
> 2 for usb2 and 3 for usb3, it is available only with upstream qemu.
> Default is 2.
>
> Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
> ---
>   docs/man/xl.cfg.pod.5       |    6 ++++++
>   tools/libxl/libxl_create.c  |    3 +++
>   tools/libxl/libxl_dm.c      |   25 ++++++++++++++++++++++++-
>   tools/libxl/libxl_types.idl |    1 +
>   tools/libxl/xl_cmdimpl.c    |    2 ++
>   5 files changed, 36 insertions(+), 1 deletion(-)
>
> diff --git a/docs/man/xl.cfg.pod.5 b/docs/man/xl.cfg.pod.5
> index 069b73f..602d428 100644
> --- a/docs/man/xl.cfg.pod.5
> +++ b/docs/man/xl.cfg.pod.5
> @@ -1154,6 +1154,12 @@ device.
>   
>   Enables or disables an emulated USB bus in the guest.
>   
> +=item B<usbversion=NUMBER>
> +
> +Specifies the type of an emulated USB bus in the guest. 1 for usb1,
> +2 for usb2 and 3 for usb3, it is available only with upstream qemu.
> +Default is 2.
> +
>   =item B<usbdevice=[ "DEVICE", "DEVICE", ...]>
>   
>   Adds B<DEVICE>s to the emulated USB bus. The USB bus must also be
> diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
> index 0c32d0b..9683740 100644
> --- a/tools/libxl/libxl_create.c
> +++ b/tools/libxl/libxl_create.c
> @@ -229,6 +229,9 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc,
>               return ERROR_INVAL;
>           }
>   
> +        if (!b_info->u.hvm.usbversion)
> +            b_info->u.hvm.usbversion = 2;
> +
>           if (b_info->u.hvm.timer_mode == LIBXL_TIMER_MODE_DEFAULT)
>               b_info->u.hvm.timer_mode =
>                   LIBXL_TIMER_MODE_NO_DELAY_FOR_MISSED_TICKS;
> diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
> index 7e54c02..aa8e131 100644
> --- a/tools/libxl/libxl_dm.c
> +++ b/tools/libxl/libxl_dm.c
> @@ -492,7 +492,30 @@ static char ** libxl__build_device_model_args_new(libxl__gc *gc,
>                       __func__);
>                   return NULL;
>               }
> -            flexarray_append(dm_args, "-usb");
> +
> +            switch (b_info->u.hvm.usbversion) {
> +            case 1:
> +                flexarray_vappend(dm_args,
> +                    "-device", "piix3-usb-uhci,id=usb", NULL);
> +                break;
> +            case 2:
> +                flexarray_vappend(dm_args, "-device","ich9-usb-ehci1,id=usb,"
> +                    "bus=pci.0,addr=0x1d.0x7", "-device","ich9-usb-uhci1,"
> +                    "masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,"
> +                    "addr=0x1d.0x0","-device","ich9-usb-uhci2,masterbus=usb.0,"
> +                    "firstport=2,bus=pci.0,addr=0x1d.0x1", "-device",
> +                    "ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,"
> +                    "addr=0x1d.0x2", NULL);

I'm just curious, why is this so complicated?  Is this likely to be 
fragile and break in the future?

Also, it's worth thinking a bit about the id -- maybe something slightly 
more descriptive, like "usb-hub-root" or something?

And as Dario said, you still need to add LIBXL_HAVE_USBVERSION to 
libxl.h.  The purpose of that is so that someone wants to write software 
that can compile against different versions of the library (say, a GUI 
VM manager or something), using features if they're present and not 
using them if they aren't.

> +                break;
> +            case 3:
> +                flexarray_vappend(dm_args,
> +                    "-device", "nec-usb-xhci,id=usb", NULL);
> +                break;
> +            default:
> +                LIBXL__LOG(CTX, LIBXL__LOG_ERROR,
> +                    "usbversion parameter is invalid must be between 1 and 3");
> +                return NULL;
> +            }
>               if (b_info->u.hvm.usbdevice) {
>                   flexarray_vappend(dm_args,
>                                     "-usbdevice", b_info->u.hvm.usbdevice, NULL);
> diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
> index d218a2d..100f36c 100644
> --- a/tools/libxl/libxl_types.idl
> +++ b/tools/libxl/libxl_types.idl
> @@ -325,6 +325,7 @@ libxl_domain_build_info = Struct("domain_build_info",[
>                                          ("serial",           string),
>                                          ("boot",             string),
>                                          ("usb",              libxl_defbool),
> +                                       ("usbversion",       integer),
>                                          # usbdevice:
>                                          # - "tablet" for absolute mouse,
>                                          # - "mouse" for PS/2 protocol relative mouse
> diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
> index 8a478ba..a618ede 100644
> --- a/tools/libxl/xl_cmdimpl.c
> +++ b/tools/libxl/xl_cmdimpl.c
> @@ -1495,6 +1495,8 @@ skip_vfb:
>           xlu_cfg_replace_string (config, "serial", &b_info->u.hvm.serial, 0);
>           xlu_cfg_replace_string (config, "boot", &b_info->u.hvm.boot, 0);
>           xlu_cfg_get_defbool(config, "usb", &b_info->u.hvm.usb, 0);
> +        if (!xlu_cfg_get_long (config, "usbversion", &l, 0))
> +            b_info->u.hvm.usbversion = l;
>           switch (xlu_cfg_get_list_as_string_list(config, "usbdevice",
>                                                   &b_info->u.hvm.usbdevice_list,
>                                                   1))