3 files changed, 79 insertions, 1 deletions

diff --git a/sys/fs/devfs/devfs.h b/sys/fs/devfs/devfs.h
index d148f8e..d77baa8 100644
--- a/sys/fs/devfs/devfs.h
+++ b/sys/fs/devfs/devfs.h
@@ -182,6 +182,8 @@ void	devfs_rules_apply(struct devfs_mount *, struct devfs_dirent *);
 void	devfs_rules_cleanup(struct devfs_mount *);
 int	devfs_rules_ioctl(struct devfs_mount *, u_long, caddr_t,
 	    struct thread *);
+void	devfs_ruleset_set(devfs_rsnum rsnum, struct devfs_mount *dm);
+void	devfs_ruleset_apply(struct devfs_mount *dm);
 int	devfs_allocv(struct devfs_dirent *, struct mount *, int,
 	    struct vnode **);
 char	*devfs_fqpn(char *, struct devfs_mount *, struct devfs_dirent *,
diff --git a/sys/fs/devfs/devfs_rule.c b/sys/fs/devfs/devfs_rule.c
index ea05797..f37dd9d 100644
--- a/sys/fs/devfs/devfs_rule.c
+++ b/sys/fs/devfs/devfs_rule.c
@@ -771,3 +771,38 @@ devfs_rules_cleanup(struct devfs_mount *dm)
 		devfs_ruleset_reap(ds);
 	}
 }
+
+/*
+ * Make rsnum the active ruleset for dm (locked)
+ */
+void
+devfs_ruleset_set(devfs_rsnum rsnum, struct devfs_mount *dm)
+{
+
+	sx_assert(&dm->dm_lock, SX_XLOCKED);
+
+	sx_xlock(&sx_rules);
+	devfs_ruleset_use(rsnum, dm);
+	sx_xunlock(&sx_rules);
+}
+
+/*
+ * Apply the current active ruleset on a mount
+ */
+void
+devfs_ruleset_apply(struct devfs_mount *dm)
+{
+	struct devfs_ruleset *ds;
+
+	sx_assert(&dm->dm_lock, SX_XLOCKED);
+
+	sx_xlock(&sx_rules);
+	if (dm->dm_ruleset == 0) {
+		sx_xunlock(&sx_rules);
+		return;
+	}
+	ds = devfs_ruleset_bynum(dm->dm_ruleset);
+	if (ds != NULL)
+		devfs_ruleset_applydm(ds, dm);
+	sx_xunlock(&sx_rules);
+}
diff --git a/sys/fs/devfs/devfs_vfsops.c b/sys/fs/devfs/devfs_vfsops.c
index 87ec162..bba4bfc 100644
--- a/sys/fs/devfs/devfs_vfsops.c
+++ b/sys/fs/devfs/devfs_vfsops.c
@@ -56,6 +56,10 @@ static vfs_unmount_t	devfs_unmount;
 static vfs_root_t	devfs_root;
 static vfs_statfs_t	devfs_statfs;
 
+static const char *devfs_opts[] = {
+	"from", "ruleset", NULL
+};
+
 /*
  * Mount the filesystem
  */
@@ -65,15 +69,46 @@ devfs_mount(struct mount *mp)
 	int error;
 	struct devfs_mount *fmp;
 	struct vnode *rvp;
+	int rsnum;
 
 	if (devfs_unr == NULL)
 		devfs_unr = new_unrhdr(0, INT_MAX, NULL);
 
 	error = 0;
 
-	if (mp->mnt_flag & (MNT_UPDATE | MNT_ROOTFS))
+	if (mp->mnt_flag & MNT_ROOTFS)
 		return (EOPNOTSUPP);
 
+	rsnum = 0;
+
+	if (mp->mnt_optnew != NULL) {
+		if (vfs_filteropt(mp->mnt_optnew, devfs_opts))
+			return (EINVAL);
+
+		if (vfs_getopt(mp->mnt_optnew, "ruleset", NULL, NULL) == 0 &&
+		    (vfs_scanopt(mp->mnt_optnew, "ruleset", "%d",
+		    &rsnum) != 1 || rsnum < 0 || rsnum > 65535))
+			error = EINVAL;
+	}
+
+	if (error) {
+		vfs_mount_error(mp, "%s", "invalid ruleset specification");
+		return (error);
+	}
+
+	if (mp->mnt_flag & MNT_UPDATE) {
+		if (rsnum != 0) {
+			fmp = mp->mnt_data;
+			if (fmp != NULL) {
+				sx_xlock(&fmp->dm_lock);
+				devfs_ruleset_set((devfs_rsnum)rsnum, fmp);
+				devfs_ruleset_apply(fmp);
+				sx_xunlock(&fmp->dm_lock);
+			}
+		}
+		return (0);
+	}
+
 	fmp = malloc(sizeof *fmp, M_DEVFS, M_WAITOK | M_ZERO);
 	fmp->dm_idx = alloc_unr(devfs_unr);
 	sx_init(&fmp->dm_lock, "devfsmount");
@@ -101,6 +136,12 @@ devfs_mount(struct mount *mp)
 		return (error);
 	}
 
+	if (rsnum != 0) {
+		sx_xlock(&fmp->dm_lock);
+		devfs_ruleset_set((devfs_rsnum)rsnum, fmp);
+		sx_xunlock(&fmp->dm_lock);
+	}
+
 	VOP_UNLOCK(rvp, 0);
 
 	vfs_mountedfrom(mp, "devfs");