fs/isofs: return f_fsid for statfs(2)

Make isofs return f_fsid info for statfs(2).
Signed-off-by: NColy Li <coly.li@suse.de>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/isofs/inode.c

@@ -923,6 +923,7 @@ static int isofs_fill_super(struct super_block *s, void *data, int silent)
 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
 {
 	struct super_block *sb = dentry->d_sb;
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 
 	buf->f_type = ISOFS_SUPER_MAGIC;
 	buf->f_bsize = sb->s_blocksize;
@@ -932,6 +933,8 @@ static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
 	buf->f_bavail = 0;
 	buf->f_files = ISOFS_SB(sb)->s_ninodes;
 	buf->f_ffree = 0;
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
 	buf->f_namelen = NAME_MAX;
 	return 0;
 }