fs/squashfs: return f_fsid for statfs(2)

Make squashfs return f_fsid info for statfs(2).

Signed-off-by: Coly Li <coly.li@suse.de>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index 681ec0d..ffa6edc 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -301,6 +301,7 @@
 static int squashfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
 	struct squashfs_sb_info *msblk = dentry->d_sb->s_fs_info;
+	u64 id = huge_encode_dev(dentry->d_sb->s_bdev->bd_dev);
 
 	TRACE("Entered squashfs_statfs\n");
 
@@ -311,6 +312,8 @@
 	buf->f_files = msblk->inodes;
 	buf->f_ffree = 0;
 	buf->f_namelen = SQUASHFS_NAME_LEN;
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
 
 	return 0;
 }