Btrfs: add tests for find_lock_delalloc_range

So both Liu and I made huge messes of find_lock_delalloc_range trying to fix
stuff, me first by fixing extent size, then him by fixing something I broke and
then me again telling him to fix it a different way.  So this is obviously a
candidate for some testing.  This patch adds a pseudo fs so we can allocate fake
inodes for tests that need an inode or pages.  Then it addes a bunch of tests to
make sure find_lock_delalloc_range is acting the way it is supposed to.  With
this patch and all of our previous patches to find_lock_delalloc_range I am sure
it is working as expected now.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c
new file mode 100644
index 000000000000..697d527377c1
--- /dev/null
+++ b/fs/btrfs/tests/btrfs-tests.c
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2013 Fusion IO.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/magic.h>
+#include "btrfs-tests.h"
+#include "../ctree.h"
+
+static struct vfsmount *test_mnt = NULL;
+
+static struct dentry *btrfs_test_mount(struct file_system_type *fs_type,
+                                       int flags, const char *dev_name,
+                                       void *data)
+{
+        return mount_pseudo(fs_type, "btrfs_test:", NULL, NULL, BTRFS_TEST_MAGIC);
+}
+
+static struct file_system_type test_type = {
+        .name           = "btrfs_test_fs",
+        .mount          = btrfs_test_mount,
+        .kill_sb        = kill_anon_super,
+};
+
+struct inode *btrfs_new_test_inode(void)
+{
+        return new_inode(test_mnt->mnt_sb);
+}
+
+int btrfs_init_test_fs(void)
+{
+        int ret;
+
+        ret = register_filesystem(&test_type);
+        if (ret) {
+                printk(KERN_ERR "btrfs: cannot register test file system\n");
+                return ret;
+        }
+
+        test_mnt = kern_mount(&test_type);
+        if (IS_ERR(test_mnt)) {
+                printk(KERN_ERR "btrfs: cannot mount test file system\n");
+                unregister_filesystem(&test_type);
+                return ret;
+        }
+        return 0;
+}
+
+void btrfs_destroy_test_fs(void)
+{
+        kern_unmount(test_mnt);
+        unregister_filesystem(&test_type);
+}