Fix the NFSv4 client for the case where mmap'd files are

written, but not msync'd by a process. A VOP_PUTPAGES()
called when VOP_RECLAIM() happens will usually fail, since
the NFSv4 Open has already been closed by VOP_INACTIVE().
Add a vm_object_page_clean() call to the NFSv4 client's
VOP_INACTIVE(), so that the write happens before the NFSv4
Open is closed. kib@ suggested using vgone() instead and
I will explore this, but this patch fixes things in the
meantime. For some reason, the VOP_PUTPAGES() is still
attaempted in VOP_RECLAIM(), but having this fail doesn't
cause any problems except a "stateid0 in write" being logged.

Reviewed by:	kib
MFC after:	1 week

1 files changed, 15 insertions, 5 deletions

diff --git a/sys/fs/nfsclient/nfs_clnode.c b/sys/fs/nfsclient/nfs_clnode.c
index 087858d..d721931 100644
--- a/sys/fs/nfsclient/nfs_clnode.c
+++ b/sys/fs/nfsclient/nfs_clnode.c
@@ -210,18 +210,28 @@ ncl_inactive(struct vop_inactive_args *ap)
 	struct nfsnode *np;
 	struct sillyrename *sp;
 	struct vnode *vp = ap->a_vp;
+	boolean_t retv;
 
 	np = VTONFS(vp);
 
 	if (NFS_ISV4(vp) && vp->v_type == VREG) {
 		/*
 		 * Since mmap()'d files do I/O after VOP_CLOSE(), the NFSv4
-		 * Close operations are delayed until now. Any dirty buffers
-		 * must be flushed before the close, so that the stateid is
-		 * available for the writes.
+		 * Close operations are delayed until now. Any dirty
+		 * buffers/pages must be flushed before the close, so that the
+		 * stateid is available for the writes.
 		 */
-		(void) ncl_flush(vp, MNT_WAIT, NULL, ap->a_td, 1, 0);
-		(void) nfsrpc_close(vp, 1, ap->a_td);
+		if (vp->v_object != NULL) {
+			VM_OBJECT_LOCK(vp->v_object);
+			retv = vm_object_page_clean(vp->v_object, 0, 0,
+			    OBJPC_SYNC);
+			VM_OBJECT_UNLOCK(vp->v_object);
+		} else
+			retv = TRUE;
+		if (retv == TRUE) {
+			(void)ncl_flush(vp, MNT_WAIT, NULL, ap->a_td, 1, 0);
+			(void)nfsrpc_close(vp, 1, ap->a_td);
+		}
 	}
 
 	mtx_lock(&np->n_mtx);