Why is the max_sectors set the 240

[Lipengcheng]

Hi,
Some special superspeed u3 disk connect xhci control. Then the u3 disk is read/write and has the Transfer error on endpoint (COMP_TX_ERR) error. However in the pc windows does not have the problem.By analysis, the windows is each transfer 64K size. The Linux is 120K size. In the scsiglue.c, the max_sectors value set the 128 and each transfer 64K size. Then the Linux system is no problem too. Why is the max_sectors set the 240?  May the max_sectors be the other values?

Best Regard
Pengcheng Li