Use a more advanced function vfs_poll() in acrn_irqfd_assign().
At the same time, modify the definition of events.
Signed-off-by: NYejune Deng <yejune.deng@gmail.com>
Signed-off-by: NShuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210221133306.33530-1-shuo.a.liu@intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>