This patch adds region file descriptors to VFIO, a simple file descriptor type that allows read/write/mmap operations on a single region of a VFIO device. This feature is particularly useful for privileged applications that use VFIO and wish to share file descriptors with unprivileged applications without handing over full control of the device. It also allows applications to use regular offsets in read/write/mmap instead of the region index + offset that must be used with device file descriptors. The current implementation is very raw (PCI only, no reference counting which is probably wrong), but I wanted to get a sense to see if this feature is desired. If it is, tips on how to implement this more correctly are appreciated. Comments welcome! Shawn Anastasio (1): vfio/pci: Introduce region file descriptors drivers/vfio/pci/vfio_pci.c | 105 ++++++++++++++++++++++++++++ drivers/vfio/pci/vfio_pci_private.h | 5 ++ include/uapi/linux/vfio.h | 14 ++++ 3 files changed, 124 insertions(+) -- 2.20.1