diff --git a/fs/aio.c b/fs/aio.c
index ac1c158..dbe699e 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -30,6 +30,7 @@
 #include <linux/highmem.h>
 #include <linux/workqueue.h>
 #include <linux/security.h>
+#include <linux/eventfd.h>
 
 #include <asm/kmap_types.h>
 #include <asm/uaccess.h>
@@ -417,6 +418,7 @@
 	req->private = NULL;
 	req->ki_iovec = NULL;
 	INIT_LIST_HEAD(&req->ki_run_list);
+	req->ki_eventfd = ERR_PTR(-EINVAL);
 
 	/* Check if the completion queue has enough free space to
 	 * accept an event from this io.
@@ -458,6 +460,8 @@
 {
 	assert_spin_locked(&ctx->ctx_lock);
 
+	if (!IS_ERR(req->ki_eventfd))
+		fput(req->ki_eventfd);
 	if (req->ki_dtor)
 		req->ki_dtor(req);
 	if (req->ki_iovec != &req->ki_inline_vec)
@@ -942,6 +946,14 @@
 		return 1;
 	}
 
+	/*
+	 * Check if the user asked us to deliver the result through an
+	 * eventfd. The eventfd_signal() function is safe to be called
+	 * from IRQ context.
+	 */
+	if (!IS_ERR(iocb->ki_eventfd))
+		eventfd_signal(iocb->ki_eventfd, 1);
+
 	info = &ctx->ring_info;
 
 	/* add a completion event to the ring buffer.
@@ -1526,8 +1538,7 @@
 	ssize_t ret;
 
 	/* enforce forwards compatibility on users */
-	if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2 ||
-		     iocb->aio_reserved3)) {
+	if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2)) {
 		pr_debug("EINVAL: io_submit: reserve field set\n");
 		return -EINVAL;
 	}
@@ -1551,6 +1562,19 @@
 		fput(file);
 		return -EAGAIN;
 	}
+	if (iocb->aio_flags & IOCB_FLAG_RESFD) {
+		/*
+		 * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an
+		 * instance of the file* now. The file descriptor must be
+		 * an eventfd() fd, and will be signaled for each completed
+		 * event using the eventfd_signal() function.
+		 */
+		req->ki_eventfd = eventfd_fget((int) iocb->aio_resfd);
+		if (unlikely(IS_ERR(req->ki_eventfd))) {
+			ret = PTR_ERR(req->ki_eventfd);
+			goto out_put_req;
+		}
+	}
 
 	req->ki_filp = file;
 	ret = put_user(req->ki_key, &user_iocb->aio_key);