[PATCH] Document syslet-rw engine

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/HOWTO b/HOWTO
index 38f5dce..e5b09fd 100644
--- a/HOWTO
+++ b/HOWTO
@@ -49,7 +49,7 @@
 
 	IO engine	How do we issue io? We could be memory mapping the
 			file, we could be using regular read/write, we
-			could be using splice, async io, or even
+			could be using splice, async io, syslet, or even
 			SG (SCSI generic sg).
 
 	IO depth	If the io engine is async, how large a queuing
@@ -270,6 +270,9 @@
 				vmsplice(2) to transfer data from user
 				space to the kernel.
 
+			syslet-rw Use the syslet system calls to make
+				regular read/write async.
+
 			sg	SCSI generic sg v3 io. May either be
 				synchronous using the SG_IO ioctl, or if
 				the target is an sg character device