aufs: add files

[pandora-kernel.git] / fs / aufs / dcsub.h

diff --git a/fs/aufs/dcsub.h b/fs/aufs/dcsub.h
new file mode 100644 (file)
index 0000000..1211304
--- /dev/null
+++ b/fs/aufs/dcsub.h
@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2005-2011 Junjiro R. Okajima
+ *
+ * This program, aufs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+/*
+ * sub-routines for dentry cache
+ */
+
+#ifndef __AUFS_DCSUB_H__
+#define __AUFS_DCSUB_H__
+
+#ifdef __KERNEL__
+
+#include <linux/dcache.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+
+struct dentry;
+
+struct au_dpage {
+       int ndentry;
+       struct dentry **dentries;
+};
+
+struct au_dcsub_pages {
+       int ndpage;
+       struct au_dpage *dpages;
+};
+
+/* ---------------------------------------------------------------------- */
+
+/* dcsub.c */
+int au_dpages_init(struct au_dcsub_pages *dpages, gfp_t gfp);
+void au_dpages_free(struct au_dcsub_pages *dpages);
+typedef int (*au_dpages_test)(struct dentry *dentry, void *arg);
+int au_dcsub_pages(struct au_dcsub_pages *dpages, struct dentry *root,
+                  au_dpages_test test, void *arg);
+int au_dcsub_pages_rev(struct au_dcsub_pages *dpages, struct dentry *dentry,
+                      int do_include, au_dpages_test test, void *arg);
+int au_dcsub_pages_rev_aufs(struct au_dcsub_pages *dpages,
+                           struct dentry *dentry, int do_include);
+int au_test_subdir(struct dentry *d1, struct dentry *d2);
+
+/* ---------------------------------------------------------------------- */
+
+static inline int au_d_hashed_positive(struct dentry *d)
+{
+       int err;
+       struct inode *inode = d->d_inode;
+       err = 0;
+       if (unlikely(d_unhashed(d) || !inode || !inode->i_nlink))
+               err = -ENOENT;
+       return err;
+}
+
+static inline int au_d_alive(struct dentry *d)
+{
+       int err;
+       struct inode *inode;
+       err = 0;
+       if (!IS_ROOT(d))
+               err = au_d_hashed_positive(d);
+       else {
+               inode = d->d_inode;
+               if (unlikely(d_unlinked(d) || !inode || !inode->i_nlink))
+                       err = -ENOENT;
+       }
+       return err;
+}
+
+static inline int au_alive_dir(struct dentry *d)
+{
+       int err;
+       err = au_d_alive(d);
+       if (unlikely(err || IS_DEADDIR(d->d_inode)))
+               err = -ENOENT;
+       return err;
+}
+
+#endif /* __KERNEL__ */
+#endif /* __AUFS_DCSUB_H__ */