bd: Add aio support to BD xlator

Volume option bd-aio controls AIO feature for BD xlator. Code taken from
posix-aio.c

Change-Id: Ib049bd59c9d3f9101d33939838322cfa808de053
BUG: 1028672
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Reviewed-on: http://review.gluster.org/5748
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

1 files changed, 41 insertions, 0 deletions

diff --git a/xlators/storage/bd/src/bd-aio.h b/xlators/storage/bd/src/bd-aio.h
new file mode 100644
index 000000000..16f686a4c
--- /dev/null
+++ b/xlators/storage/bd/src/bd-aio.h
@@ -0,0 +1,41 @@
+/*
+   Copyright IBM, Corp. 2013
+
+   This file is part of GlusterFS.
+
+   This file is licensed to you under your choice of the GNU Lesser
+   General Public License, version 3 or any later version (LGPLv3 or
+   later), or the GNU General Public License, version 2 (GPLv2), in all
+   cases as published by the Free Software Foundation.
+*/
+#ifndef _BD_AIO_H
+#define _BD_AIO_H
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "xlator.h"
+#include "glusterfs.h"
+
+/*
+ * Maximum number of concurrently submitted IO events. The heaviest load
+ * GlusterFS has been able to handle had 60-80 concurrent calls
+ */
+#define BD_AIO_MAX_NR_EVENTS 256
+
+/* Maximum number of completed IO operations to reap per getevents syscall */
+#define BD_AIO_MAX_NR_GETEVENTS 16
+
+int bd_aio_on (xlator_t *this);
+int bd_aio_off (xlator_t *this);
+
+int bd_readv (call_frame_t *frame, xlator_t *this, fd_t *fd, size_t size,
+                      off_t offset, uint32_t flags, dict_t *xdata);
+
+int bd_writev (call_frame_t *frame, xlator_t *this, fd_t *fd,
+                       struct iovec *vector, int32_t count, off_t offset,
+                       uint32_t flags, struct iobref *iobref, dict_t *xdata);
+
+#endif /* !_BD_AIO_H */