fs/efs: return f_fsid for statfs(2)

Make efs return f_fsid info for statfs(2), and do a little variable
renaming in efs_statfs().
Signed-off-by: NColy Li <coly.li@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/efs/super.c

@@ -329,18 +329,22 @@ static int efs_fill_super(struct super_block *s, void *d, int silent)
 }
 
 static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
-	struct efs_sb_info *sb = SUPER_INFO(dentry->d_sb);
+	struct super_block *sb = dentry->d_sb;
+	struct efs_sb_info *sbi = SUPER_INFO(sb);
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 
 	buf->f_type    = EFS_SUPER_MAGIC;	/* efs magic number */
 	buf->f_bsize   = EFS_BLOCKSIZE;		/* blocksize */
-	buf->f_blocks  = sb->total_groups *	/* total data blocks */
-			(sb->group_size - sb->inode_blocks);
-	buf->f_bfree   = sb->data_free;		/* free data blocks */
-	buf->f_bavail  = sb->data_free;		/* free blocks for non-root */
-	buf->f_files   = sb->total_groups *	/* total inodes */
-			sb->inode_blocks *
+	buf->f_blocks  = sbi->total_groups *	/* total data blocks */
+			(sbi->group_size - sbi->inode_blocks);
+	buf->f_bfree   = sbi->data_free;	/* free data blocks */
+	buf->f_bavail  = sbi->data_free;	/* free blocks for non-root */
+	buf->f_files   = sbi->total_groups *	/* total inodes */
+			sbi->inode_blocks *
 			(EFS_BLOCKSIZE / sizeof(struct efs_dinode));
-	buf->f_ffree   = sb->inode_free;	/* free inodes */
+	buf->f_ffree   = sbi->inode_free;	/* free inodes */
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
 	buf->f_namelen = EFS_MAXNAMELEN;	/* max filename length */
 
 	return 0;