Hi David, On Wed, Jul 03, 2019 at 09:02:59AM +0200, David Marchand wrote: > Hello, > > On Wed, Jul 3, 2019 at 7:47 AM Tiwei Bie <tiwei....@intel.com> wrote: > > The value 40 used in VFIO_GET_REGION_ADDR() is a private value > (VFIO_PCI_OFFSET_SHIFT) defined in Linux kernel source [1]. It > is not part of VFIO API, and we should not depend on it. > > [1] https://github.com/torvalds/linux/blob/6fbc7275c7a9/drivers/vfio/pci/ > vfio_pci_private.h#L19 > > > > I did not follow linux kernel changes, is there something that would change > this offset? > It looks like a cleanup (did not look into the details yet), do we need this > now?
In VFIO/mdev [1], the offset can be something different. It depends on the parent device. It's not just a cleanup. It's a preparation for the mdev support in DPDK. [1] https://github.com/torvalds/linux/blob/master/Documentation/vfio-mediated-device.txt Thanks, Tiwei > > -- > David Marchand
