[PATCH v0 RFC 0/2] xl/libxl support for PVUSB

[Bo Cao <caobosimon@gmail.com>]

Finally I have a workable version xl/libxl support for PVUSB. Most of
its commands work property now, but there are still some probelm to be solved.
Please take a loot and give me some advices.

== What have been implemented ? ==
I have implemented libxl functions for PVUSB in libxl_usb.c. It mainly consists of two part:
usbctrl_add/remove/list and usb_add/remove/list in which usbctrl denote usb controller in which
usd device can be plugged in. I don't use "ao_dev" in libxl_deivce_usbctrl_add since we don't need to
execute hotplug script for usbctrl and without "ao_dev", adding default usbctrl for usb device
would be easier.

For the cammands to manipulate usb device such as "xl usb-attach" and "xl usb-detach", this patch now only
support to specify usb devices by their interface in sysfs. Using this interface, we can read usb device
information through sysfs and bind/unbind usb device. (The support for mapping the "lsusb" bus:addr to the
sysfs usb interface will come later).

== What needs to do next ? ==
There are two main problems to be solved.

1.  PVUSB Options in VM Guest's Configuration File
    The interface in VM Guest's configuration file to add usb device is: "usb=[interface="1-1"]".
But the problem is now is that after the default usbctrl is added, the state of usbctrl is "2", e,g, "XenbusStateInitWait",
waiting for xen-usbfront to connect. The xen-usbfront in VM Guest isn't loaded. Therefore, "sysfs_intf_write"
will report error. Does anyone have any clue how to solve this?

2. sysfs_intf_write
    In the process of "xl usb-attach domid intf=1-1", after writing "1-1" to Xenstore entry, we need to
bind the controller of this usb device to usbback driver so that it can be used by VM Guest. For exampele,
for usb device "1-1", it's controller interface maybe "1-1:1.0", and we write this value to "/sys/bus/usb/driver/usbback/bind".
But for some devices, they have two controllers, for example "1-1:1.0" and "1-1:1.1". I think this means it has two functions,
such as usbhid and usb-storage. So in this case, we bind the two controller to usbback?

========
There maybe some errors or bugs in the codes. Feel free to tell me.

Cheers,

- Simon

---
CC: George Dunlap <george.dunlap@eu.citrix.com>
CC: Ian Jackson <ian.jackson@citrix.com>
CC: Ian Campbell <ian.campbell@citrix.com>
CC: Pasi Kärkkäinen <pasik@iki.fi>
CC: Lars Kurth <lars.kurth@citrix.com>



_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel