System, method and computer-readable medium using map tables in a cache to manage write requests to a raid storage array

A system, comprising:

• a redundant array of inexpensive disks (RAID) storage array;
• and
• a storage controller having processing system comprising one or more processors and a memory, the processing system programmed or configured to:
• receive a write request including a host address and a data block;
• identify a primary map table entry in response to the host address, the primary map table having a plurality of primary map table entries, each primary map table entry identifying one of a plurality of secondary map tables;
• identify a secondary map table in response to an identified primary map table entry identified by the host address, each secondary map table having a plurality of secondary map table entries, each secondary map table entry identifying a storage location in the RAID storage array;
• identify an indicated secondary map table entry in response to the host address;
• serialize the write request into a RAID stripe including the data block;
• store a block address in the identified secondary map table entry;
• and
• write the RAID stripe including the data block to the RAID storage array, the block address stored in the identified secondary map table entry indicating a location of the data block in the RAID storage array.

A computer program product comprising a computer readable medium having stored thereon in computer executable non-transitory form instructions that, when executed on a processing system of a redundant array of inexpensive disks (RAID) storage controller, cause the processing system to:

• receive a write request including a host address and a data block;
• identify a primary map table entry in response to the host address, the primary map table having a plurality of primary map table entries, each primary map table entry identifying one of a plurality of secondary map tables;
• identify a secondary map table in response to an identified primary map table entry identified by the host address, each secondary map table having a plurality of secondary map table entries, each secondary map table entry identifying a storage location in the RAID storage array;
• identify an indicated secondary map table entry in response to the host address;
• serialize the write request into a RAID stripe including the data block;
• store a block address in the identified secondary map table entry;
• and
• write the RAID stripe including the data block to the RAID storage array, the block address stored in the identified secondary map table entry indicating a location of the data block in the RAID storage array.