fs/sysv: return f_fsid for statfs(2)

Make sysv file system return f_fsid info for statfs(2).
Signed-off-by: NColy Li <coly.li@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/sysv/inode.c

@@ -90,6 +90,7 @@ static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
 	struct super_block *sb = dentry->d_sb;
 	struct sysv_sb_info *sbi = SYSV_SB(sb);
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 
 	buf->f_type = sb->s_magic;
 	buf->f_bsize = sb->s_blocksize;
@@ -98,6 +99,8 @@ static int sysv_statfs(struct dentry *dentry, struct kstatfs *buf)
 	buf->f_files = sbi->s_ninodes;
 	buf->f_ffree = sysv_count_free_inodes(sb);
 	buf->f_namelen = SYSV_NAMELEN;
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
 	return 0;
 }