Re: [Xen-devel] [Patch V2 2/3] usb: Introduce Xen pvUSB frontend

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Jun 12, 2015 at 05:33:46PM +0100, David Vrabel wrote:
> On 12/06/15 17:20, Greg KH wrote:
> > On Fri, Jun 12, 2015 at 04:10:00PM +0200, Juergen Gross wrote:
> >> Introduces the Xen pvUSB frontend. With pvUSB it is possible for a Xen
> >> domU to communicate with a USB device assigned to that domU. The
> >> communication is all done via the pvUSB backend in a driver domain
> >> (usually Dom0) which is owner of the physical device.
> >>
> >> The code is taken from the pvUSB implementation in Xen done by Fujitsu
> >> based on Linux kernel 2.6.18.
> >>
> >> Changes from the original version are:
> >> - port to upstream kernel
> >> - put all code in just one source file
> >> - move module to appropriate location in kernel tree
> >> - adapt to Linux style guide
> >> - minor code modifications to increase readability
> >>
> >> Signed-off-by: Juergen Gross <jgross@suse.com>
> >> ---
> >>  drivers/usb/Kconfig            |    2 +
> >>  drivers/usb/Makefile           |    2 +
> >>  drivers/usb/xen/Kconfig        |   10 +
> >>  drivers/usb/xen/Makefile       |    5 +
> >>  drivers/usb/xen/xen-usbfront.c | 1647 ++++++++++++++++++++++++++++++++++++++++
> > 
> > A subdirectory for a single file?  That seems like overkill, don't you
> > think?  As this is a USB "host" driver, why not put it in that
> > directory?
> > 
> > Also, last time these patches were posted, people asked why you can't
> > use libusb/usbfs instead, what happened with that?  Or usbip?
> 
> Using libusb was for the backend driver.  This frontend driver is a host
> controller (which is why it should be drivers/usb/host/xen-pv-hcd.c or
> similar).

Then document the heck out of that please.