Linux kernel stable tree (mirror) https://git.radix-linux.su/kernel/linux.git/atom?h=v6.7 2021-02-09T09:58:19+00:00 2021-02-09T09:58:19+00:00 Shuo Liu shuo.a.liu@intel.com 2021-02-07T03:10:37+00:00 urn:sha1:d8ad515156b66e7e79a6e4c814f997ee54eb47c7 ioeventfd is a mechanism to register PIO/MMIO regions to trigger an eventfd signal when written to by a User VM. ACRN userspace can register any arbitrary I/O address with a corresponding eventfd and then pass the eventfd to a specific end-point of interest for handling. Vhost is a kernel-level virtio server which uses eventfd for signalling. To support vhost on ACRN, ioeventfd is introduced in HSM. A new I/O client dedicated to ioeventfd is associated with a User VM during VM creation. HSM provides ioctls to associate an I/O region with a eventfd. The I/O client signals a eventfd once its corresponding I/O region is matched with an I/O request. Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Yu Wang <yu1.wang@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Zhi Wang <zhi.a.wang@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuo Liu <shuo.a.liu@intel.com> Link: https://lore.kernel.org/r/20210207031040.49576-16-shuo.a.liu@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>