Add qemu_aio_process_queue()

We'll leave some AIO completions unhandled when we can't call the callback.
qemu_aio_process_queue() is used later to run any callbacks that are left and
can be run then.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/qemu-aio.h b/qemu-aio.h
index f262344af3..3bdd749f80 100644
--- a/qemu-aio.h
+++ b/qemu-aio.h
@@ -20,6 +20,11 @@
 /* Returns 1 if there are still outstanding AIO requests; 0 otherwise */
 typedef int (AioFlushHandler)(void *opaque);
 
+/* Runs all currently allowed AIO callbacks of completed requests in the
+ * respective AIO backend. Returns 0 if no requests was handled, non-zero
+ * if at least one queued request was handled. */
+typedef int (AioProcessQueue)(void *opaque);
+
 /* Flush any pending AIO operation. This function will block until all
  * outstanding AIO operations have been completed or cancelled. */
 void qemu_aio_flush(void);
@@ -30,6 +35,13 @@ void qemu_aio_flush(void);
  * result of executing I/O completion or bh callbacks. */
 void qemu_aio_wait(void);
 
+/*
+ * Runs all currently allowed AIO callbacks of completed requests. Returns 0
+ * if no requests were handled, non-zero if at least one request was
+ * processed.
+ */
+int qemu_aio_process_queue(void);
+
 /* Register a file descriptor and associated callbacks.  Behaves very similarly
  * to qemu_set_fd_handler2.  Unlike qemu_set_fd_handler2, these callbacks will
  * be invoked when using either qemu_aio_wait() or qemu_aio_flush().
@@ -41,6 +53,7 @@ int qemu_aio_set_fd_handler(int fd,
                             IOHandler *io_read,
                             IOHandler *io_write,
                             AioFlushHandler *io_flush,
+                            AioProcessQueue *io_process_queue,
                             void *opaque);
 
 #endif