1 files changed, 71 insertions, 18 deletions

diff --git a/sys/fs/tmpfs/tmpfs_subr.c b/sys/fs/tmpfs/tmpfs_subr.c
index 1aa9a0d..a4fa168 100644
--- a/sys/fs/tmpfs/tmpfs_subr.c
+++ b/sys/fs/tmpfs/tmpfs_subr.c
@@ -131,6 +131,26 @@ tmpfs_pages_check_avail(struct tmpfs_mount *tmp, size_t req_pages)
 	return (1);
 }
 
+void
+tmpfs_ref_node(struct tmpfs_node *node)
+{
+
+	TMPFS_NODE_LOCK(node);
+	tmpfs_ref_node_locked(node);
+	TMPFS_NODE_UNLOCK(node);
+}
+
+void
+tmpfs_ref_node_locked(struct tmpfs_node *node)
+{
+
+	TMPFS_NODE_ASSERT_LOCKED(node);
+	KASSERT(node->tn_refcount > 0, ("node %p zero refcount", node));
+	KASSERT(node->tn_refcount < UINT_MAX, ("node %p refcount %u", node,
+	    node->tn_refcount));
+	node->tn_refcount++;
+}
+
 /*
  * Allocates a new node of type 'type' inside the 'tmp' mount point, with
  * its owner set to 'uid', its group to 'gid' and its mode set to 'mode',
@@ -205,6 +225,7 @@ tmpfs_alloc_node(struct mount *mp, struct tmpfs_mount *tmp, enum vtype type,
 	nnode->tn_gid = gid;
 	nnode->tn_mode = mode;
 	nnode->tn_id = alloc_unr(tmp->tm_ino_unr);
+	nnode->tn_refcount = 1;
 
 	/* Type-specific initialization. */
 	switch (nnode->tn_type) {
@@ -258,7 +279,9 @@ tmpfs_alloc_node(struct mount *mp, struct tmpfs_mount *tmp, enum vtype type,
 
 	TMPFS_LOCK(tmp);
 	LIST_INSERT_HEAD(&tmp->tm_nodes_used, nnode, tn_entries);
+	nnode->tn_attached = true;
 	tmp->tm_nodes_inuse++;
+	tmp->tm_refcount++;
 	TMPFS_UNLOCK(tmp);
 
 	*node = nnode;
@@ -272,18 +295,40 @@ tmpfs_alloc_node(struct mount *mp, struct tmpfs_mount *tmp, enum vtype type,
 void
 tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node)
 {
+
+	TMPFS_LOCK(tmp);
+	TMPFS_NODE_LOCK(node);
+	if (!tmpfs_free_node_locked(tmp, node, false)) {
+		TMPFS_NODE_UNLOCK(node);
+		TMPFS_UNLOCK(tmp);
+	}
+}
+
+bool
+tmpfs_free_node_locked(struct tmpfs_mount *tmp, struct tmpfs_node *node,
+    bool detach)
+{
 	vm_object_t uobj;
 
+	TMPFS_MP_ASSERT_LOCKED(tmp);
+	TMPFS_NODE_ASSERT_LOCKED(node);
+	KASSERT(node->tn_refcount > 0, ("node %p refcount zero", node));
+
+	node->tn_refcount--;
+	if (node->tn_attached && (detach || node->tn_refcount == 0)) {
+		MPASS(tmp->tm_nodes_inuse > 0);
+		tmp->tm_nodes_inuse--;
+		LIST_REMOVE(node, tn_entries);
+		node->tn_attached = false;
+	}
+	if (node->tn_refcount > 0)
+		return (false);
+
 #ifdef INVARIANTS
-	TMPFS_NODE_LOCK(node);
 	MPASS(node->tn_vnode == NULL);
 	MPASS((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0);
-	TMPFS_NODE_UNLOCK(node);
 #endif
-
-	TMPFS_LOCK(tmp);
-	LIST_REMOVE(node, tn_entries);
-	tmp->tm_nodes_inuse--;
+	TMPFS_NODE_UNLOCK(node);
 	TMPFS_UNLOCK(tmp);
 
 	switch (node->tn_type) {
@@ -323,6 +368,9 @@ tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node)
 
 	free_unr(tmp->tm_ino_unr, node->tn_id);
 	uma_zfree(tmp->tm_node_pool, node);
+	TMPFS_LOCK(tmp);
+	tmpfs_free_tmp(tmp);
+	return (true);
 }
 
 static __inline uint32_t
@@ -468,13 +516,16 @@ tmpfs_alloc_vp(struct mount *mp, struct tmpfs_node *node, int lkflag,
     struct vnode **vpp)
 {
 	struct vnode *vp;
+	struct tmpfs_mount *tm;
 	vm_object_t object;
 	int error;
 
 	error = 0;
-loop:
+	tm = VFS_TO_TMPFS(mp);
 	TMPFS_NODE_LOCK(node);
-loop1:
+	tmpfs_ref_node_locked(node);
+loop:
+	TMPFS_NODE_ASSERT_LOCKED(node);
 	if ((vp = node->tn_vnode) != NULL) {
 		MPASS((node->tn_vpstate & TMPFS_VNODE_DOOMED) == 0);
 		VI_LOCK(vp);
@@ -494,12 +545,14 @@ loop1:
 				msleep(&node->tn_vnode, TMPFS_NODE_MTX(node),
 				    0, "tmpfsE", 0);
 			}
-			goto loop1;
+			goto loop;
 		}
 		TMPFS_NODE_UNLOCK(node);
 		error = vget(vp, lkflag | LK_INTERLOCK, curthread);
-		if (error == ENOENT)
+		if (error == ENOENT) {
+			TMPFS_NODE_LOCK(node);
 			goto loop;
+		}
 		if (error != 0) {
 			vp = NULL;
 			goto out;
@@ -511,6 +564,7 @@ loop1:
 		 */
 		if (node->tn_vnode == NULL || node->tn_vnode != vp) {
 			vput(vp);
+			TMPFS_NODE_LOCK(node);
 			goto loop;
 		}
 
@@ -532,11 +586,9 @@ loop1:
 	if (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) {
 		node->tn_vpstate |= TMPFS_VNODE_WANT;
 		error = msleep((caddr_t) &node->tn_vpstate,
-		    TMPFS_NODE_MTX(node), PDROP | PCATCH,
-		    "tmpfs_alloc_vp", 0);
-		if (error)
-			return error;
-
+		    TMPFS_NODE_MTX(node), 0, "tmpfs_alloc_vp", 0);
+		if (error != 0)
+			goto out;
 		goto loop;
 	} else
 		node->tn_vpstate |= TMPFS_VNODE_ALLOCATING;
@@ -610,16 +662,17 @@ unlock:
 		TMPFS_NODE_UNLOCK(node);
 
 out:
-	*vpp = vp;
+	if (error == 0) {
+		*vpp = vp;
 
 #ifdef INVARIANTS
-	if (error == 0) {
 		MPASS(*vpp != NULL && VOP_ISLOCKED(*vpp));
 		TMPFS_NODE_LOCK(node);
 		MPASS(*vpp == node->tn_vnode);
 		TMPFS_NODE_UNLOCK(node);
-	}
 #endif
+	}
+	tmpfs_free_node(tm, node);
 
 	return (error);
 }