Add support for a last-close handler.

Revert the module version bumps; they're quite pointless as long as the
only pseudofs consumer is linprocfs, which is in the tree.

3 files changed, 38 insertions, 3 deletions

diff --git a/sys/fs/pseudofs/pseudofs.c b/sys/fs/pseudofs/pseudofs.c
index f7ecaab..6bb69a7 100644
--- a/sys/fs/pseudofs/pseudofs.c
+++ b/sys/fs/pseudofs/pseudofs.c
@@ -392,4 +392,4 @@ static moduledata_t pseudofs_data = {
 	NULL
 };
 DECLARE_MODULE(pseudofs, pseudofs_data, SI_SUB_EXEC, SI_ORDER_FIRST);
-MODULE_VERSION(pseudofs, 3);
+MODULE_VERSION(pseudofs, 1);
diff --git a/sys/fs/pseudofs/pseudofs.h b/sys/fs/pseudofs/pseudofs.h
index b21d9b6..2432748 100644
--- a/sys/fs/pseudofs/pseudofs.h
+++ b/sys/fs/pseudofs/pseudofs.h
@@ -133,6 +133,15 @@ typedef int (*pfs_vis_t)(PFS_VIS_ARGS);
 typedef int (*pfs_ioctl_t)(PFS_IOCTL_ARGS);
 
 /*
+ * Last-close callback
+ */
+#define PFS_CLOSE_ARGS \
+	struct thread *td, struct proc *p, struct pfs_node *pn
+#define PFS_CLOSE_PROTO(name) \
+	int name(PFS_CLOSE_ARGS);
+typedef int (*pfs_close_t)(PFS_CLOSE_ARGS);
+
+/*
  * pfs_info: describes a pseudofs instance
  */
 struct pfs_info {
@@ -160,6 +169,7 @@ struct pfs_node {
 #define pn_func		u1._pn_func
 #define pn_nodes	u1._pn_nodes
 	pfs_ioctl_t		 pn_ioctl;
+	pfs_close_t		 pn_close;
 	pfs_attr_t		 pn_attr;
 	pfs_vis_t		 pn_vis;
 	void			*pn_data;
@@ -245,6 +255,6 @@ static struct vfsops name##_vfsops = {					\
 };									\
 VFS_SET(name##_vfsops, name, VFCF_SYNTHETIC);				\
 MODULE_VERSION(name, version);						\
-MODULE_DEPEND(name, pseudofs, 3, 3, 3);
+MODULE_DEPEND(name, pseudofs, 1, 1, 1);
 
 #endif
diff --git a/sys/fs/pseudofs/pseudofs_vnops.c b/sys/fs/pseudofs/pseudofs_vnops.c
index 91614d6..1152c11 100644
--- a/sys/fs/pseudofs/pseudofs_vnops.c
+++ b/sys/fs/pseudofs/pseudofs_vnops.c
@@ -121,7 +121,32 @@ pfs_access(struct vop_access_args *va)
 static int
 pfs_close(struct vop_close_args *va)
 {
-	PFS_RETURN (0);
+	struct vnode *vn = va->a_vp;
+	struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data;
+	struct pfs_node *pn = pvd->pvd_pn;
+	struct proc *proc;
+	int error;
+
+	PFS_TRACE((pn->pn_name));
+
+	/*
+	 * Do nothing unless this is the last close and the node has a
+	 * last-close handler.
+	 */
+	if (vn->v_usecount > 1 || pn->pn_close == NULL)
+		PFS_RETURN (0);
+
+	if (pvd->pvd_pid != NO_PID)
+		proc = pfind(pvd->pvd_pid);
+	else
+		proc = NULL;
+	
+	error = (pn->pn_close)(va->a_td, proc, pn);
+	
+	if (proc != NULL)
+		PROC_UNLOCK(proc);
+	
+	PFS_RETURN (error);
 }
 
 /*