From ea5642c0ea537ef3c9da946d4f26a8f597b68622 Mon Sep 17 00:00:00 2001
From: Iurii Konovalenko <iurii.konovalenko@xxxxxxxxxxxxxxx>
Date: Thu, 19 Mar 2015 13:55:44 +0200
Subject: [PATCH] arm: xen: hack to make xen files unregular

Change-Id: I0bc32867ca12dad78aa5f532a9c606fab9a3d1db
Signed-off-by: Iurii Konovalenko <iurii.konovalenko@xxxxxxxxxxxxxxx>
---
 drivers/xen/xenfs/super.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 70 insertions(+), 1 deletion(-)

diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c
index 06092e0..1f7e74c 100644
--- a/drivers/xen/xenfs/super.c
+++ b/drivers/xen/xenfs/super.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/magic.h>
+#include <linux/pagemap.h>
 
 #include <xen/xen.h>
 
@@ -42,6 +43,74 @@ static const struct file_operations capabilities_file_ops = {
 	.llseek = default_llseek,
 };
 
+static const struct super_operations xen_simple_super_operations = {
+	.statfs		= simple_statfs,
+};
+
+static int xen_simple_fill_super(struct super_block *s, unsigned long magic,
+	      struct tree_descr *files)
+{
+struct inode *inode;
+struct dentry *root;
+struct dentry *dentry;
+int i;
+
+s->s_blocksize = PAGE_CACHE_SIZE;
+s->s_blocksize_bits = PAGE_CACHE_SHIFT;
+s->s_magic = magic;
+s->s_op = &xen_simple_super_operations;
+s->s_time_gran = 1;
+
+inode = new_inode(s);
+if (!inode)
+	return -ENOMEM;
+/*
+* because the root inode is 1, the files array must not contain an
+* entry at index 1
+*/
+inode->i_ino = 1;
+inode->i_mode = S_IFDIR | 0755;
+inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+inode->i_op = &simple_dir_inode_operations;
+inode->i_fop = &simple_dir_operations;
+set_nlink(inode, 2);
+root = d_make_root(inode);
+if (!root)
+	return -ENOMEM;
+for (i = 0; !files->name || files->name[0]; i++, files++) {
+	if (!files->name)
+		continue;
+
+	/* warn if it tries to conflict with the root inode */
+	if (unlikely(i == 1))
+		printk(KERN_WARNING "%s: %s passed in a files array"
+			"with an index of 1!\n", __func__,
+			s->s_type->name);
+
+	dentry = d_alloc_name(root, files->name);
+	if (!dentry)
+		goto out;
+	inode = new_inode(s);
+	if (!inode) {
+		dput(dentry);
+		goto out;
+	}
+	inode->i_mode = files->mode;
+	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+	inode->i_fop = files->ops;
+	inode->i_ino = i;
+	d_add(dentry, inode);
+}
+s->s_root = root;
+return 0;
+out:
+d_genocide(root);
+shrink_dcache_parent(root);
+dput(root);
+return -ENOMEM;
+}
+
+
 static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
 {
 	static struct tree_descr xenfs_files[] = {
@@ -60,7 +129,7 @@ static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
 		{""},
 	};
 
-	return simple_fill_super(sb, XENFS_SUPER_MAGIC,
+	return xen_simple_fill_super(sb, XENFS_SUPER_MAGIC,
 			xen_initial_domain() ? xenfs_init_files : xenfs_files);
 }
 
-- 
1.9.1