Regularize the vop_stdlock'ing protocol across all the filesystems

that use it. Specifically, vop_stdlock uses the lock pointed to by
vp->v_vnlock. By default, getnewvnode sets up vp->v_vnlock to
reference vp->v_lock. Filesystems that wish to use the default
do not need to allocate a lock at the front of their node structure
(as some still did) or do a lockinit. They can simply start using
vn_lock/VOP_UNLOCK. Filesystems that wish to manage their own locks,
but still use the vop_stdlock functions (such as nullfs) can simply
replace vp->v_vnlock with a pointer to the lock that they wish to
have used for the vnode. Such filesystems are responsible for
setting the vp->v_vnlock back to the default in their vop_reclaim
routine (e.g., vp->v_vnlock = &vp->v_lock).

In theory, this set of changes cleans up the existing filesystem
lock interface and should have no function change to the existing
locking scheme.

Sponsored by:	DARPA & NAI Labs.

2 files changed, 1 insertions, 5 deletions

diff --git a/sys/fs/udf/udf_vfsops.c b/sys/fs/udf/udf_vfsops.c
index b23e30f..b41b86b 100644
--- a/sys/fs/udf/udf_vfsops.c
+++ b/sys/fs/udf/udf_vfsops.c
@@ -613,8 +613,6 @@ udf_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
 	unode->i_dev = udfmp->im_dev;
 	unode->udfmp = udfmp;
 	vp->v_data = unode;
-	lockinit(&vp->v_lock, PINOD, "udfnode", 0, 0);
-	vp->v_vnlock = &vp->v_lock;
 	VREF(udfmp->im_devvp);
 	udf_hashins(unode);
 
diff --git a/sys/fs/udf/udf_vnops.c b/sys/fs/udf/udf_vnops.c
index 2f71d86..4e4a4b6 100644
--- a/sys/fs/udf/udf_vnops.c
+++ b/sys/fs/udf/udf_vnops.c
@@ -135,8 +135,7 @@ udf_hashins(struct udf_node *node)
 	mtx_lock(&udfmp->hash_mtx);
 	TAILQ_INSERT_TAIL(&udfmp->udf_tqh, node, tq);
 	mtx_unlock(&udfmp->hash_mtx);
-	lockmgr(&node->i_vnode->v_lock, LK_EXCLUSIVE, (struct mtx *)0,
-		curthread);
+	vn_lock(node->i_vnode, LK_EXCLUSIVE | LK_RETRY, curthread);
 
 	return (0);
 }
@@ -1028,7 +1027,6 @@ udf_reclaim(struct vop_reclaim_args *a)
 
 		if (unode->fentry != NULL)
 			FREE(unode->fentry, M_UDFFENTRY);
-		lockdestroy(&unode->i_vnode->v_lock);
 		uma_zfree(udf_zone_node, unode);
 		vp->v_data = NULL;
 	}