[PATCH v2 35/50] convert selinuxfs

[Al Viro]

Tree has invariant part + two subtrees that get replaced upon each
policy load.  Invariant parts stay for the lifetime of filesystem,
these two subdirs - from policy load to policy load (serialized
on lock_rename(root, ...)).

All object creations are via d_alloc_name()+d_add() inside selinuxfs,
all removals are via simple_recursive_removal().

Turn those d_add() into d_make_persistent()+dput() and that's mostly it.

Signed-off-by: Al Viro <viro at zeniv.linux.org.uk>
---
 security/selinux/selinuxfs.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index f088776dbbd3..eae565358db4 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -1205,7 +1205,8 @@ static struct dentry *sel_attach(struct dentry *parent, const char *name,
 		iput(inode);
 		return ERR_PTR(-ENOMEM);
 	}
-	d_add(dentry, inode);
+	d_make_persistent(dentry, inode);
+	dput(dentry);
 	return dentry;
 }
 
@@ -1934,10 +1935,11 @@ static struct dentry *sel_make_swapover_dir(struct super_block *sb,
 	/* directory inodes start off with i_nlink == 2 (for "." entry) */
 	inc_nlink(inode);
 	inode_lock(sb->s_root->d_inode);
-	d_add(dentry, inode);
+	d_make_persistent(dentry, inode);
 	inc_nlink(sb->s_root->d_inode);
 	inode_unlock(sb->s_root->d_inode);
-	return dentry;
+	dput(dentry);
+	return dentry;	// borrowed
 }
 
 #define NULL_FILE_NAME "null"
@@ -2080,7 +2082,7 @@ static int sel_init_fs_context(struct fs_context *fc)
 static void sel_kill_sb(struct super_block *sb)
 {
 	selinux_fs_info_free(sb);
-	kill_litter_super(sb);
+	kill_anon_super(sb);
 }
 
 static struct file_system_type sel_fs_type = {
-- 
2.47.3