event_notifier: cleanups around event_notifier_set_handler

Remove the useless is_external argument.  Since the iohandler
AioContext is never used for block devices, aio_disable_external
is never called on it.  This lets us remove stubs/iohandler.c.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

hw/usb/ccid-card-emulated.c

@@ -407,7 +407,7 @@ static int init_event_notifier(EmulatedState *card)
         DPRINTF(card, 2, "event notifier creation failed\n");
         return -1;
     }
-    event_notifier_set_handler(&card->notifier, false, card_event_handler);
+    event_notifier_set_handler(&card->notifier, card_event_handler);
     return 0;
 }
 

hw/virtio/virtio.c

@@ -2090,10 +2090,10 @@ void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
                                                 bool with_irqfd)
 {
     if (assign && !with_irqfd) {
-        event_notifier_set_handler(&vq->guest_notifier, false,
+        event_notifier_set_handler(&vq->guest_notifier,
                                    virtio_queue_guest_notifier_read);
     } else {
-        event_notifier_set_handler(&vq->guest_notifier, false, NULL);
+        event_notifier_set_handler(&vq->guest_notifier, NULL);
     }
     if (!assign) {
         /* Test and clear notifier before closing it,
@@ -2262,7 +2262,7 @@ static int virtio_device_start_ioeventfd_impl(VirtIODevice *vdev)
             err = r;
             goto assign_error;
         }
-        event_notifier_set_handler(&vq->host_notifier, true,
+        event_notifier_set_handler(&vq->host_notifier,
                                    virtio_queue_host_notifier_read);
     }
 
@@ -2283,7 +2283,7 @@ assign_error:
             continue;
         }
 
-        event_notifier_set_handler(&vq->host_notifier, true, NULL);
+        event_notifier_set_handler(&vq->host_notifier, NULL);
         r = virtio_bus_set_host_notifier(qbus, n, false);
         assert(r >= 0);
     }
@@ -2309,7 +2309,7 @@ static void virtio_device_stop_ioeventfd_impl(VirtIODevice *vdev)
         if (!virtio_queue_get_num(vdev, n)) {
             continue;
         }
-        event_notifier_set_handler(&vq->host_notifier, true, NULL);
+        event_notifier_set_handler(&vq->host_notifier, NULL);
         r = virtio_bus_set_host_notifier(qbus, n, false);
         assert(r >= 0);
     }

include/qemu/event_notifier.h

@@ -34,9 +34,6 @@ int event_notifier_init(EventNotifier *, int active);
 void event_notifier_cleanup(EventNotifier *);
 int event_notifier_set(EventNotifier *);
 int event_notifier_test_and_clear(EventNotifier *);
-int event_notifier_set_handler(EventNotifier *,
-                               bool is_external,
-                               EventNotifierHandler *);
 
 #ifdef CONFIG_POSIX
 void event_notifier_init_fd(EventNotifier *, int fd);

include/qemu/main-loop.h

@@ -203,6 +203,21 @@ void qemu_set_fd_handler(int fd,
                          IOHandler *fd_write,
                          void *opaque);
 
+
+/**
+ * event_notifier_set_handler: Register an EventNotifier with the main loop
+ *
+ * This function tells the main loop to wake up whenever the
+ * #EventNotifier was set.
+ *
+ * @e: The #EventNotifier to be observed.
+ *
+ * @handler: A level-triggered callback that is fired when @e
+ * has been set.  @e is passed to it as a parameter.
+ */
+void event_notifier_set_handler(EventNotifier *e,
+                                EventNotifierHandler *handler);
+
 GSource *iohandler_get_g_source(void);
 AioContext *iohandler_get_aio_context(void);
 #ifdef CONFIG_POSIX

iohandler.c

@@ -66,6 +66,14 @@ void qemu_set_fd_handler(int fd,
                        fd_read, fd_write, NULL, opaque);
 }
 
+void event_notifier_set_handler(EventNotifier *e,
+                                EventNotifierHandler *handler)
+{
+    iohandler_init();
+    aio_set_event_notifier(iohandler_ctx, e, false,
+                           handler, NULL);
+}
+
 /* reaping of zombies.  right now we're not passing the status to
    anyone, but it would be possible to add a callback.  */
 #ifndef _WIN32

stubs/Makefile.objs

@@ -35,6 +35,5 @@ stub-obj-y += kvm.o
 stub-obj-y += qmp_pc_dimm_device_list.o
 stub-obj-y += target-monitor-defs.o
 stub-obj-y += target-get-monitor-def.o
-stub-obj-y += iohandler.o
 stub-obj-y += pc_madt_cpu_entry.o
 stub-obj-y += migration-colo.o

stubs/iohandler.c

@@ -1,8 +0,0 @@
-#include "qemu/osdep.h"
-#include "qemu-common.h"
-#include "qemu/main-loop.h"
-
-AioContext *iohandler_get_aio_context(void)
-{
-    abort();
-}

target/i386/hyperv.c

@@ -12,6 +12,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/main-loop.h"
 #include "hyperv.h"
 #include "standard-headers/asm-x86/hyperv.h"
 
@@ -88,7 +89,7 @@ HvSintRoute *kvm_hv_sint_route_create(uint32_t vcpu_id, uint32_t sint,
         goto err_sint_set_notifier;
     }
 
-    event_notifier_set_handler(&sint_route->sint_ack_notifier, false,
+    event_notifier_set_handler(&sint_route->sint_ack_notifier,
                                kvm_hv_sint_ack_handler);
 
     gsi = kvm_irqchip_add_hv_sint_route(kvm_state, vcpu_id, sint);
@@ -112,7 +113,7 @@ HvSintRoute *kvm_hv_sint_route_create(uint32_t vcpu_id, uint32_t sint,
 err_irqfd:
     kvm_irqchip_release_virq(kvm_state, gsi);
 err_gsi:
-    event_notifier_set_handler(&sint_route->sint_ack_notifier, false, NULL);
+    event_notifier_set_handler(&sint_route->sint_ack_notifier, NULL);
     event_notifier_cleanup(&sint_route->sint_ack_notifier);
 err_sint_set_notifier:
     event_notifier_cleanup(&sint_route->sint_set_notifier);
@@ -128,7 +129,7 @@ void kvm_hv_sint_route_destroy(HvSintRoute *sint_route)
                                           &sint_route->sint_set_notifier,
                                           sint_route->gsi);
     kvm_irqchip_release_virq(kvm_state, sint_route->gsi);
-    event_notifier_set_handler(&sint_route->sint_ack_notifier, false, NULL);
+    event_notifier_set_handler(&sint_route->sint_ack_notifier, NULL);
     event_notifier_cleanup(&sint_route->sint_ack_notifier);
     event_notifier_cleanup(&sint_route->sint_set_notifier);
     g_free(sint_route);

util/event_notifier-posix.c

@@ -90,15 +90,6 @@ int event_notifier_get_fd(const EventNotifier *e)
     return e->rfd;
 }
 
-int event_notifier_set_handler(EventNotifier *e,
-                               bool is_external,
-                               EventNotifierHandler *handler)
-{
-    aio_set_fd_handler(iohandler_get_aio_context(), e->rfd, is_external,
-                       (IOHandler *)handler, NULL, NULL, e);
-    return 0;
-}
-
 int event_notifier_set(EventNotifier *e)
 {
     static const uint64_t value = 1;

util/event_notifier-win32.c

@@ -32,18 +32,6 @@ HANDLE event_notifier_get_handle(EventNotifier *e)
     return e->event;
 }
 
-int event_notifier_set_handler(EventNotifier *e,
-                               bool is_external,
-                               EventNotifierHandler *handler)
-{
-    if (handler) {
-        return qemu_add_wait_object(e->event, (IOHandler *)handler, e);
-    } else {
-        qemu_del_wait_object(e->event, (IOHandler *)handler, e);
-        return 0;
-    }
-}
-
 int event_notifier_set(EventNotifier *e)
 {
     SetEvent(e->event);