Storage device with SCSI formatting
View Patent ↗Provided are a method, system, and an article of manufacture for detecting errors while accessing a storage device. A host system writes an identical initialization pattern into each block of a plurality of blocks while formatting the storage device. Each block of the plurality of blocks has a checksum field capable of containing a value. Any host system generates an error when data from a retrieved block from the plurality of blocks computes to a checksum that is different from the value contained within the checksum field for the retrieved block, and the retrieved block does not contain the initialization pattern.
1. A method for formatting a storage device into a plurality of blocks of a block size, comprising:
reserving a set of bits within each of the plurality of blocks to store a pattern;
reserving a checksum field within each of the plurality of blocks to store a checksum;
formatting the storage device into the plurality of blocks; and
during the formatting, writing the pattern into the set of bits within each of the plurality of blocks, wherein no checksum value is written to the checksum field during the formatting;
wherein the formatting comprises executing a SCSI FORMAT UNIT command, further comprising:
setting a FMTDATA field in the FORMAT UNIT command field within data structures of the FORMAT UNIT command;
setting an IP field in a DEFECT LIST HEADER field within the data structures of the FORMAT UNIT command;
setting a PATTERN TYPE to be hexadecimal 01 in an INITIALIZATION PATTERN DESCRIPTOR field within the data structures of the FORMAT UNIT command; and
setting an INITIALIZATION PATTERN LENGTH and an INITIALIZATION PATTERN field in the INITIALIZATION PATTERN DESCRIPTOR field within the data structures of the FORMAT UNIT command.
2. The method of claim 1 , where the checksum field occupies the same location as the set of bits within each of the plurality of plurality of blocks.
3. The method of claim 1 , wherein the pattern and checksum field are at identical locations in each of the plurality of blocks.
4. The method of claim 1 , wherein the block size on the storage device is increased as a result of storing the checksum.
5. The method of claim 1 , wherein the SCSI FORMAT UNIT command is configured by a host system and executed by the storage device.
6. The method of claim 1 , wherein the storage device is a member of a set of storage devices comprising a Direct Access Storage Device (DASD), Just a Bunch of Disks (JBOD), a Redundant Array of Independent Disks (RAID), a flexible disk, a rigid disk, a tape library and an optical library.
7. A system for formatting a storage device into a plurality of blocks of a block size, comprising:
means for reserving a set of bits within each of the plurality of blocks to store a pattern;
means for reserving a checksum field within each of the plurality of blocks to store a checksum;
means for formatting the storage device into the plurality of blocks; and
during the formatting, means for writing the pattern into the set of bits within each of the plurality of blocks, wherein no checksum value is written to the checksum field during the formatting;
wherein the means for formatting comprises executing a SCSI FORMAT UNIT command, wherein the executing further comprises:
setting a FMTDATA field in the FORMAT UNIT command field within data structures of the FORMAT UNIT command;
setting an IP field in a DEFECT LIST HEADER field within the data structures of the FORMAT UNIT command;
setting a PATTERN TYPE to be hexadecimal 01 in an INITIALIZATION PATTERN DESCRIPTOR field within the data structures of the FORMAT UNIT command; and
setting an INITIALIZATION PATTERN LENGTH and an INITIALIZATION PATTERN field in the INITIALIZATION PATTERN DESCRIPTOR field within the data structures of the FORMAT UNIT command.
8. An article of manufacture including code for formatting a storage device into a plurality of blocks of a block size, wherein the code causes operations to be performed, the operations comprising:
reserving a set of bits within each of the plurality of blocks to store a pattern;
reserving a checksum field within each of the plurality of blocks to store a checksum;
formatting the storage device into the plurality of blocks; and
during the formatting, writing the pattern into the set of bits within each of the plurality of blocks, wherein no checksum value is written to the checksum field during the formatting;
wherein the formatting comprises executing of a SCSI FORMAT UNIT command, further comprising:
setting a FMTDATA field in the FORMAT UNIT command field within data structures of the FORMAT UNIT command;
setting an IP field in a DEFECT LIST HEADER field within the data structures of the FORMAT UNIT command;
setting a PATTERN TYPE to be hexadecimal 01 in an INITIALIZATION PATTERN DESCRIPTOR field within the data structures of the FORMAT UNIT command; and
setting an INITIALIZATION PATTERN LENGTH and an INITIALIZATION PATTERN field in the INITIALIZATION PATTERN DESCRIPTOR field within the data structures of the FORMAT UNIT command.
9. The article of manufacture of claim 8 , where the checksum field occupies the same location as the set of bits within each of the plurality of plurality of blocks.
10. The article of manufacture of claim 8 , wherein the pattern and checksum field are at identical locations in each of the plurality of blocks.
11. The article of manufacture of claim 8 , wherein the block size on the storage device is increased as a result of storing the checksum.
12. The article of manufacture of claim 8 , wherein the SCSI FORMAT UNIT command is configured by a host system and executed by the storage device.
13. The article of manufacture of claim 8 , wherein the storage device is a member of a set of storage devices comprising a Direct Access Storage Device (DASD), Just a Bunch of Disks (JBOD), a Redundant Array of Independent Disks (RAID), a flexible disk, a rigid disk, a tape library and an optical library.