[GFS2] fix file_system_type leak on gfs2meta mount

get_gfs2_sb does a get_fs_type without doing a put_filesystem and
thus leaking a file_system_type reference everytime it's called.

Just use gfs2_fs_type directly instead of doing the lookup and thus
fix the problem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

fs/gfs2/ops_fstype.c

@@ -943,7 +943,6 @@ static struct super_block* get_gfs2_sb(const char *dev_name)
 {
 	struct kstat stat;
 	struct nameidata nd;
-	struct file_system_type *fstype;
 	struct super_block *sb = NULL, *s;
 	int error;
 
@@ -955,8 +954,7 @@ static struct super_block* get_gfs2_sb(const char *dev_name)
 	}
 	error = vfs_getattr(nd.path.mnt, nd.path.dentry, &stat);
 
-	fstype = get_fs_type("gfs2");
-	list_for_each_entry(s, &fstype->fs_supers, s_instances) {
+	list_for_each_entry(s, &gfs2_fs_type.fs_supers, s_instances) {
 		if ((S_ISBLK(stat.mode) && s->s_dev == stat.rdev) ||
 		    (S_ISDIR(stat.mode) &&
 		     s == nd.path.dentry->d_inode->i_sb)) {