1 files changed, 115 insertions, 10 deletions

diff --git a/fs/libfs.c b/fs/libfs.c
index cb1fb4b9b637..102edfd39000 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -20,11 +20,6 @@
 
 #include "internal.h"
 
-static inline int simple_positive(struct dentry *dentry)
-{
-	return d_really_is_positive(dentry) && !d_unhashed(dentry);
-}
-
 int simple_getattr(struct vfsmount *mnt, struct dentry *dentry,
 		   struct kstat *stat)
 {
@@ -1024,15 +1019,18 @@ int noop_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 }
 EXPORT_SYMBOL(noop_fsync);
 
-void kfree_put_link(struct dentry *dentry, struct nameidata *nd,
-				void *cookie)
+void kfree_put_link(struct inode *unused, void *cookie)
 {
-	char *s = nd_get_link(nd);
-	if (!IS_ERR(s))
-		kfree(s);
+	kfree(cookie);
 }
 EXPORT_SYMBOL(kfree_put_link);
 
+void free_page_put_link(struct inode *unused, void *cookie)
+{
+	free_page((unsigned long) cookie);
+}
+EXPORT_SYMBOL(free_page_put_link);
+
 /*
  * nop .set_page_dirty method so that people can use .page_mkwrite on
  * anon inodes.
@@ -1093,3 +1091,110 @@ simple_nosetlease(struct file *filp, long arg, struct file_lock **flp,
 	return -EINVAL;
 }
 EXPORT_SYMBOL(simple_nosetlease);
+
+const char *simple_follow_link(struct dentry *dentry, void **cookie)
+{
+	return d_inode(dentry)->i_link;
+}
+EXPORT_SYMBOL(simple_follow_link);
+
+const struct inode_operations simple_symlink_inode_operations = {
+	.follow_link = simple_follow_link,
+	.readlink = generic_readlink
+};
+EXPORT_SYMBOL(simple_symlink_inode_operations);
+
+/*
+ * Operations for a permanently empty directory.
+ */
+static struct dentry *empty_dir_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+	return ERR_PTR(-ENOENT);
+}
+
+static int empty_dir_getattr(struct vfsmount *mnt, struct dentry *dentry,
+				 struct kstat *stat)
+{
+	struct inode *inode = d_inode(dentry);
+	generic_fillattr(inode, stat);
+	return 0;
+}
+
+static int empty_dir_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	return -EPERM;
+}
+
+static int empty_dir_setxattr(struct dentry *dentry, const char *name,
+			      const void *value, size_t size, int flags)
+{
+	return -EOPNOTSUPP;
+}
+
+static ssize_t empty_dir_getxattr(struct dentry *dentry, const char *name,
+				  void *value, size_t size)
+{
+	return -EOPNOTSUPP;
+}
+
+static int empty_dir_removexattr(struct dentry *dentry, const char *name)
+{
+	return -EOPNOTSUPP;
+}
+
+static ssize_t empty_dir_listxattr(struct dentry *dentry, char *list, size_t size)
+{
+	return -EOPNOTSUPP;
+}
+
+static const struct inode_operations empty_dir_inode_operations = {
+	.lookup		= empty_dir_lookup,
+	.permission	= generic_permission,
+	.setattr	= empty_dir_setattr,
+	.getattr	= empty_dir_getattr,
+	.setxattr	= empty_dir_setxattr,
+	.getxattr	= empty_dir_getxattr,
+	.removexattr	= empty_dir_removexattr,
+	.listxattr	= empty_dir_listxattr,
+};
+
+static loff_t empty_dir_llseek(struct file *file, loff_t offset, int whence)
+{
+	/* An empty directory has two entries . and .. at offsets 0 and 1 */
+	return generic_file_llseek_size(file, offset, whence, 2, 2);
+}
+
+static int empty_dir_readdir(struct file *file, struct dir_context *ctx)
+{
+	dir_emit_dots(file, ctx);
+	return 0;
+}
+
+static const struct file_operations empty_dir_operations = {
+	.llseek		= empty_dir_llseek,
+	.read		= generic_read_dir,
+	.iterate	= empty_dir_readdir,
+	.fsync		= noop_fsync,
+};
+
+
+void make_empty_dir_inode(struct inode *inode)
+{
+	set_nlink(inode, 2);
+	inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
+	inode->i_uid = GLOBAL_ROOT_UID;
+	inode->i_gid = GLOBAL_ROOT_GID;
+	inode->i_rdev = 0;
+	inode->i_size = 2;
+	inode->i_blkbits = PAGE_SHIFT;
+	inode->i_blocks = 0;
+
+	inode->i_op = &empty_dir_inode_operations;
+	inode->i_fop = &empty_dir_operations;
+}
+
+bool is_empty_dir_inode(struct inode *inode)
+{
+	return (inode->i_fop == &empty_dir_operations) &&
+		(inode->i_op == &empty_dir_inode_operations);
+}