User Manual

SCSI Commands Reference Manual, Rev. J 167

www.seagate.com Direct Access Block commands (SPC-5 and SBC-4)

3.28 REASSIGN BLOCKS command

3.28.1 REASSIGN BLOCKS command overview

The REASSIGN BLOCKS command (see table 132) requests that the device server reassign defective logical blocks to another area

on the medium set aside for this purpose. The device server should also record the location of the defective logical blocks in the

GLIST, if supported. This command shall not alter the contents of the PLIST.

The parameter list provided in the data-out buffer contains a defective LBA list that contains the LBAs of the logical blocks to be

reassigned. The device server shall reassign the parts of the medium used for each logical block in the defective LBA list. More

than one physical block may be relocated by each LBA. If the device server is able to recover user data and protection

information, if any, from the original logical block, it shall write the recovered user data and any protection information to the

reassigned logical block. If the LBA is unmapped, then the device server shall cause the LBA to become mapped and write the

data that was retrieved during a read operation specifying the LBA that was reassigned to the logical block (see SBC-4). If the

device server is unable to recover user data and protection information, if any, it shall write vendor-specific data as the user data

and shall write a default value of FFFFFFFF_FFFFFFFFh as the protection information, if enabled. The data in all other logical

blocks on the medium shall be preserved.

NOTE The effect of specifying a logical block to be reassigned that previously has been reassigned is to

reassign the logical block again. Although not likely, over the life of the medium, a logical block may

be assigned to multiple physical block addresses until no more spare locations remain on the

medium.

LONGLBA (Long LBA) bit

0 A long LBA (LONGLBA) bit set to zero specifies that the REASSIGN BLOCKS defective LBA list contains four byte LBAs.

1 A LONGLBA bit set to one specifies that the REASSIGN BLOCKS defective LBA list contains eight byte LBAs.

Table 132 REASSIGN BLOCKS command

Bit

Byte

7 6 5 4 3 2 1 0

OPERATION CODE (07h)

Reserved LONGLBA LONGLIST

Reserved

. . .

CONTROL