MFC r279536:

Make fuse(4) respect FOPEN_DIRECT_IO.  This is required for correct
operation of GlusterFS.

PR:		192701
Submitted by:	harsha at harshavardhana.net
Reviewed by:	kib@
Sponsored by:	The FreeBSD Foundation

3 files changed, 29 insertions, 1 deletions

diff --git a/sys/fs/fuse/fuse_node.c b/sys/fs/fuse/fuse_node.c
index ea10c96..a6119dd 100644
--- a/sys/fs/fuse/fuse_node.c
+++ b/sys/fs/fuse/fuse_node.c
@@ -273,8 +273,26 @@ fuse_vnode_open(struct vnode *vp, int32_t fuse_open_flags, struct thread *td)
          * Funcation is called for every vnode open.
          * Merge fuse_open_flags it may be 0
          *
-         * XXXIP: Handle FOPEN_DIRECT_IO and FOPEN_KEEP_CACHE
+         * XXXIP: Handle FOPEN_KEEP_CACHE
          */
+        /*
+	  * Ideally speaking, direct io should be enabled on
+         * fd's but do not see of any way of providing that
+         * this implementation.
+
+         * Also cannot think of a reason why would two
+         * different fd's on same vnode would like
+         * have DIRECT_IO turned on and off. But linux
+         * based implementation works on an fd not an
+         * inode and provides such a feature.
+         *
+         * XXXIP: Handle fd based DIRECT_IO
+         */
+	if (fuse_open_flags & FOPEN_DIRECT_IO) {
+		VTOFUD(vp)->flag |= FN_DIRECTIO;
+	} else {
+	        VTOFUD(vp)->flag &= ~FN_DIRECTIO;
+	}
 
 	if (vnode_vtype(vp) == VREG) {
 		/* XXXIP prevent getattr, by using cached node size */
diff --git a/sys/fs/fuse/fuse_node.h b/sys/fs/fuse/fuse_node.h
index 2f1434f..dcdc9ff 100644
--- a/sys/fs/fuse/fuse_node.h
+++ b/sys/fs/fuse/fuse_node.h
@@ -67,6 +67,7 @@
 #define FN_FLUSHINPROG       0x00000040
 #define FN_FLUSHWANT         0x00000080
 #define FN_SIZECHANGE        0x00000100
+#define FN_DIRECTIO          0x00000200
 
 struct fuse_vnode_data {
     /** self **/
diff --git a/sys/fs/fuse/fuse_vnops.c b/sys/fs/fuse/fuse_vnops.c
index 820d69f..f2d0188 100644
--- a/sys/fs/fuse/fuse_vnops.c
+++ b/sys/fs/fuse/fuse_vnops.c
@@ -1173,6 +1173,11 @@ fuse_vnop_read(struct vop_read_args *ap)
 	if (fuse_isdeadfs(vp)) {
 		return ENXIO;
 	}
+
+	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
+		ioflag |= IO_DIRECT;
+	}
+
 	return fuse_io_dispatch(vp, uio, ioflag, cred);
 }
 
@@ -1712,6 +1717,10 @@ fuse_vnop_write(struct vop_write_args *ap)
 	}
 	fuse_vnode_refreshsize(vp, cred);
 
+	if (VTOFUD(vp)->flag & FN_DIRECTIO) {
+		ioflag |= IO_DIRECT;
+	}
+
 	return fuse_io_dispatch(vp, uio, ioflag, cred);
 }