[PATCH] Separate io engines into separate loadable objects

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/engines/fio-engine-libaio.c b/engines/fio-engine-libaio.c
new file mode 100644
index 0000000..703808b
--- /dev/null
+++ b/engines/fio-engine-libaio.c
@@ -0,0 +1,131 @@
+/*
+ * native linux aio io engine
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <assert.h>
+#include "fio.h"
+#include "os.h"
+
+#define ev_to_iou(ev)	(struct io_u *) ((unsigned long) (ev)->obj)
+
+struct libaio_data {
+	io_context_t aio_ctx;
+	struct io_event *aio_events;
+};
+
+static int fio_libaio_sync(struct thread_data *td)
+{
+	return fsync(td->fd);
+}
+
+static int fio_libaio_prep(struct thread_data *td, struct io_u *io_u)
+{
+	if (io_u->ddir == DDIR_READ)
+		io_prep_pread(&io_u->iocb, td->fd, io_u->buf, io_u->buflen, io_u->offset);
+	else
+		io_prep_pwrite(&io_u->iocb, td->fd, io_u->buf, io_u->buflen, io_u->offset);
+
+	return 0;
+}
+
+static struct io_u *fio_libaio_event(struct thread_data *td, int event)
+{
+	struct libaio_data *ld = td->io_ops->data;
+
+	return ev_to_iou(ld->aio_events + event);
+}
+
+static int fio_libaio_getevents(struct thread_data *td, int min, int max,
+				struct timespec *t)
+{
+	struct libaio_data *ld = td->io_ops->data;
+	long r;
+
+	do {
+		r = io_getevents(ld->aio_ctx, min, max, ld->aio_events, t);
+		if (r == -EAGAIN) {
+			usleep(100);
+			continue;
+		} else if (r == -EINTR)
+			continue;
+		else
+			break;
+	} while (1);
+
+	return (int) r;
+}
+
+static int fio_libaio_queue(struct thread_data *td, struct io_u *io_u)
+{
+	struct libaio_data *ld = td->io_ops->data;
+	struct iocb *iocb = &io_u->iocb;
+	long ret;
+
+	do {
+		ret = io_submit(ld->aio_ctx, 1, &iocb);
+		if (ret == 1)
+			return 0;
+		else if (ret == -EAGAIN)
+			usleep(100);
+		else if (ret == -EINTR)
+			continue;
+		else
+			break;
+	} while (1);
+
+	return (int) ret;
+
+}
+
+static int fio_libaio_cancel(struct thread_data *td, struct io_u *io_u)
+{
+	struct libaio_data *ld = td->io_ops->data;
+
+	return io_cancel(ld->aio_ctx, &io_u->iocb, ld->aio_events);
+}
+
+static void fio_libaio_cleanup(struct thread_data *td)
+{
+	struct libaio_data *ld = td->io_ops->data;
+
+	if (ld) {
+		io_destroy(ld->aio_ctx);
+		if (ld->aio_events)
+			free(ld->aio_events);
+
+		free(ld);
+		td->io_ops->data = NULL;
+	}
+}
+
+static int fio_libaio_init(struct thread_data *td)
+{
+	struct libaio_data *ld = malloc(sizeof(*ld));
+
+	memset(ld, 0, sizeof(*ld));
+	if (io_queue_init(td->iodepth, &ld->aio_ctx)) {
+		td_verror(td, errno);
+		return 1;
+	}
+
+	ld->aio_events = malloc(td->iodepth * sizeof(struct io_event));
+	td->io_ops->data = ld;
+	return 0;
+}
+
+struct ioengine_ops ioengine = {
+	.name		= "libaio",
+	.version	= FIO_IOOPS_VERSION,
+	.init		= fio_libaio_init,
+	.prep		= fio_libaio_prep,
+	.queue		= fio_libaio_queue,
+	.cancel		= fio_libaio_cancel,
+	.getevents	= fio_libaio_getevents,
+	.event		= fio_libaio_event,
+	.cleanup	= fio_libaio_cleanup,
+	.sync		= fio_libaio_sync,
+};