Win32 event notifiers are not file descriptors, so they will not be able
to use qemu_set_fd_handler.  But even if for now we only have a POSIX
version of EventNotifier, we can add a specific function that wraps
the call.

The wrapper passes the EventNotifier as the opaque value so that it will
be used with container_of.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

The function is useless (and unused).
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

EventNotifier right now cannot be used as an inter-thread communication
primitive.  It only works if something else (the kernel) sets the eventfd.
Add a primitive to signal an EventNotifier that another thread is waiting
on.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

All files under GPLv2 will get GPLv2+ changes starting tomorrow.
event_notifier.c and exec-obsolete.h were only ever touched by Red Hat
employees and can be relicensed now.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Has no business in hw/.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

event notifiers are slightly generalized eventfd descriptors. Current
implementation depends on eventfd because vhost is the only user, and
vhost depends on eventfd anyway, but a stub is provided for non-eventfd
case.

We'll be able to further generalize this when another user comes along
and we see how to best do this.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>