1 files changed, 89 insertions, 15 deletions

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 94ab3c06317a..704a8c8fe19a 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -51,6 +51,95 @@ static void unlock_dir(struct dentry *dir)
 	dput(dir);
 }
 
+static int ecryptfs_inode_test(struct inode *inode, void *lower_inode)
+{
+	if (ecryptfs_inode_to_lower(inode) == (struct inode *)lower_inode)
+		return 1;
+	return 0;
+}
+
+static int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
+{
+	ecryptfs_set_inode_lower(inode, (struct inode *)lower_inode);
+	inode->i_ino = ((struct inode *)lower_inode)->i_ino;
+	inode->i_version++;
+	inode->i_op = &ecryptfs_main_iops;
+	inode->i_fop = &ecryptfs_main_fops;
+	inode->i_mapping->a_ops = &ecryptfs_aops;
+	return 0;
+}
+
+struct inode *ecryptfs_get_inode(struct inode *lower_inode,
+				 struct super_block *sb)
+{
+	struct inode *inode;
+	int rc = 0;
+
+	if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb)) {
+		rc = -EXDEV;
+		goto out;
+	}
+	if (!igrab(lower_inode)) {
+		rc = -ESTALE;
+		goto out;
+	}
+	inode = iget5_locked(sb, (unsigned long)lower_inode,
+			     ecryptfs_inode_test, ecryptfs_inode_set,
+			     lower_inode);
+	if (!inode) {
+		rc = -EACCES;
+		iput(lower_inode);
+		goto out;
+	}
+	if (inode->i_state & I_NEW)
+		unlock_new_inode(inode);
+	else
+		iput(lower_inode);
+	if (S_ISLNK(lower_inode->i_mode))
+		inode->i_op = &ecryptfs_symlink_iops;
+	else if (S_ISDIR(lower_inode->i_mode))
+		inode->i_op = &ecryptfs_dir_iops;
+	if (S_ISDIR(lower_inode->i_mode))
+		inode->i_fop = &ecryptfs_dir_fops;
+	if (special_file(lower_inode->i_mode))
+		init_special_inode(inode, lower_inode->i_mode,
+				   lower_inode->i_rdev);
+	fsstack_copy_attr_all(inode, lower_inode);
+	/* This size will be overwritten for real files w/ headers and
+	 * other metadata */
+	fsstack_copy_inode_size(inode, lower_inode);
+	return inode;
+out:
+	return ERR_PTR(rc);
+}
+
+#define ECRYPTFS_INTERPOSE_FLAG_D_ADD                 0x00000001
+/**
+ * ecryptfs_interpose
+ * @lower_dentry: Existing dentry in the lower filesystem
+ * @dentry: ecryptfs' dentry
+ * @sb: ecryptfs's super_block
+ * @flags: flags to govern behavior of interpose procedure
+ *
+ * Interposes upper and lower dentries.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_interpose(struct dentry *lower_dentry,
+			      struct dentry *dentry, struct super_block *sb,
+			      u32 flags)
+{
+	struct inode *lower_inode = lower_dentry->d_inode;
+	struct inode *inode = ecryptfs_get_inode(lower_inode, sb);
+	if (IS_ERR(inode))
+		return PTR_ERR(inode);
+	if (flags & ECRYPTFS_INTERPOSE_FLAG_D_ADD)
+		d_add(dentry, inode);
+	else
+		d_instantiate(dentry, inode);
+	return 0;
+}
+
 /**
  * ecryptfs_create_underlying_file
  * @lower_dir_inode: inode of the parent in the lower fs of the new file
@@ -1079,21 +1168,6 @@ out:
 	return rc;
 }
 
-int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode)
-{
-	if ((ecryptfs_inode_to_lower(inode)
-	     == (struct inode *)candidate_lower_inode))
-		return 1;
-	else
-		return 0;
-}
-
-int ecryptfs_inode_set(struct inode *inode, void *lower_inode)
-{
-	ecryptfs_init_inode(inode, (struct inode *)lower_inode);
-	return 0;
-}
-
 const struct inode_operations ecryptfs_symlink_iops = {
 	.readlink = ecryptfs_readlink,
 	.follow_link = ecryptfs_follow_link,