[vbox-dev] [PATCH 2/2] vgdrvLinuxIOCtl: Always return standard Linux errno values

[Hans de Goede]

Hi,

On 08/07/2017 07:06 PM, Knut St. Osmundsen wrote:
> Hi Hans,
> 
> sorry but I'm not convinced this is really useful and improving the code. We will fix this properly in a cross platform manner eventually, I hope.

No problem, I've already reverted the changes in the vboxguest version
I'm working on for the mainline kernel.

On 08/08/2017 01:02 AM, Knut St. Osmundsen wrote:
 > Just to clarify the design a little here.
 >
 > The I/O controls aren't part of any user space API.  They are supposed
 > (*) to be 104% internal and only used between the driver (VBoxGuest) and
 > the ring-3 library (VBoxGuestLib).  User land clients will call
 > functions in VBoxGuestLib and not care at all how that functions
 > internally, only that the jobs get done and that the right status code
 > gets returned for each call.
 >
 > Regarding the idea that Michael proposed of having a last status
 > associated with the session: Doesn't work with multithreaded clients
 > like VBoxService.  Also, it's inefficient to have to go back to ring-0
 > again just to retrieve a status code, especially if the guest is running
 > in raw-mode.

Understood.

Regards,

Hans