From: Junjiro Okajima <hooanon05@yahoo.co.jp>
initial commit
aufs special handling for inode attributes on FUSE branch
Signed-off-by: Junjiro Okajima <hooanon05@yahoo.co.jp>
---
fs/aufs/br_fuse.c | 109 +++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 109 insertions(+), 0 deletions(-)
diff --git a/fs/aufs/br_fuse.c b/fs/aufs/br_fuse.c
new file mode 100644
index 0000000..295139b
--- /dev/null
+++ b/fs/aufs/br_fuse.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2008 Junjiro 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
+ */
+
+/*
+ * special handling for inode attributes on FUSE branch
+ *
+ * $Id: br_fuse.c,v 1.2 2008/04/21 01:32:05 sfjro Exp $
+ */
+
+#include "aufs.h"
+
+/* h_mnt can be NULL, is it safe? */
+int au_update_fuse_h_inode(struct vfsmount *h_mnt, struct dentry *h_dentry)
+{
+ int err;
+ struct kstat st;
+
+ LKTRTrace("%.*s\n", AuDLNPair(h_dentry));
+
+ err = 0;
+ if (unlikely(h_dentry->d_inode
+ //&& atomic_read(&h_dentry->d_inode->i_count)
+ && au_test_fuse(h_dentry->d_sb))) {
+ err = vfsub_getattr(h_mnt, h_dentry, &st, /*dlgt*/0);
+ if (unlikely(err)) {
+ AuDbg("err %d\n", err);
+ au_debug_on();
+ AuDbgDentry(h_dentry);
+ au_debug_off();
+ WARN_ON(err);
+ }
+ }
+ return err;
+}
+
+/* currently, for fuse only */
+int aufs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *st)
+{
+ int err;
+ struct inode *inode, *h_inode;
+ struct dentry *h_dentry;
+
+ LKTRTrace("%.*s\n", AuDLNPair(dentry));
+
+ err = 0;
+ aufs_read_lock(dentry, AuLock_IR);
+ inode = dentry->d_inode;
+ h_inode = au_h_iptr(inode, au_ibstart(inode));
+ if (unlikely(au_test_fuse(h_inode->i_sb))) {
+ h_dentry = d_find_alias(h_inode);
+ /* simply gave up updating fuse inode */
+ if (h_dentry) {
+ /*ignore*/
+ if (!au_update_fuse_h_inode(NULL, h_dentry))
+ au_cpup_attr_all(inode);
+ dput(h_dentry);
+ }
+ }
+ generic_fillattr(inode, st);
+
+ aufs_read_unlock(dentry, AuLock_IR);
+ return err;
+}
+
+#if 0 // temp
+/*
+ * This function was born after a discussion with the FUSE developer.
+ * The inode attributes on a filesystem who defines i_op->getattr()
+ * is unreliable since such fs may not maintain the attributes at lookup.
+ * This function doesn't want the result of stat, instead wants the side-effect
+ * which refreshes the attributes.
+ * Hmm, there seems to be no such filesystem except fuse.
+ */
+int vfsub_i_attr(struct vfsmount *mnt, struct dentry *dentry, int dlgt)
+{
+ int err;
+ struct inode *inode;
+ struct inode_operations *op;
+ struct kstat st;
+
+ inode = dentry->d_inode;
+ AuDebugOn(!inode);
+
+ err = 0;
+ op = inode->i_op;
+ if (unlikely(op && op->getattr && !au_test_aufs(dentry->d_sb))) {
+ err = security_inode_getattr(mnt, dentry);
+ if (!err)
+ err = op->getattr(mnt, dentry, &st);
+ }
+ AuTraceErr(err);
+ return err;
+}
+#endif
--
1.4.4.4
--
