US 8,914,549 B2 · Data storage architecture extension system and method

Abstract

A data storage architecture extension (DAX) system and method that permits multiple disk drive storage elements to be logically daisy-chained to allow a single host bus adapter (HBA) to view the storage elements as one logical disk drive is disclosed. The system/method may be broadly described as comprising a pass-thru disk drive controller (PTDDC) further comprising a HBA port, a disk drive interface port, pass-thru input port, and a pass-thru output port. The PTDDC intercepts and translates the HBA port input to the requirements of an individual disk drive connected to the drive interface port. Each PTDDC may be daisy-chained to other PTDDCs to permit a plethora of disk drives to be associated with a given HBA, with the first PTDDC providing a presentation interface to the HBA integrating all disk drive storage connected to the PTDDCs. The system/method also permits RAID configuration of disk drives using one or more PTDDCs.

A serial advanced technology attachment (SATA) disk drive identification method for individually identifying a daisy-chained data storage architecture extension system comprising a pass-thru disk drive controller (PTDDC), said PTDDC further comprising:

(a) pass-thru input (PTI) port;
(b) disk drive interface (DDI) port;
and
(c) pass-thru output (PTO) port;
wherein
said PTI port, said DDI port, and said PTO port are SATA interfaces;
said PTDDC is configured to connect a plurality of PTDDCs to form a serial daisy-chain by only interconnecting the PTO port of one PTDDC to the PTI port of another PTDDC in said daisy-chain;
said PTDDC is configured to present a continuous logical block address space via said PTI port comprising disk drives electrically connected to PTDDCs in said daisy-chain;
said PTDDC is configured to receive disk drive data access command (DDDAC) input via said PTI port;
said PTDDC is configured to translate said DDDAC and electrically transmit said translation via said DDI port in a form suitable for use by any attached and logically addressed disk drive electrically connected to said DDI port;
said PTDDC determines when said DDDAC falls within the logical block address (LBA) range of said attached disk drive, and if so, passes said DDDAC to said attached disk drive after modifying said DDDAC to account for said LBA range mapped by said attached disk drive;
said PTDDC determines when said DDDAC falls within said LBA range of said attached disk drive, and if not, said DDDAC is passed via said PTO port to the PTI port of any daisy-chained PTDDC attached to said PTDDC PTO port;
and
said PTDDC logically connects said DDI port from said attached disk drive with said PTI port to pass-thru data transfers requested by said DDDAC to/from said attached disk drive and said PTI port;
wherein said method further comprises the steps of:
(1) storing a unique electronic serial number (ESN) within said PTDDC via the steps of:
(a) issuing a DRIVE RESET command via a host bus adapter (HBA) to the first PTDDC in said PTDDC serial daisy-chain;
(b) propagating said DRIVE RESET command through all PTDDCs in said PTDDC daisy-chain;
(c) setting a local PTDDC_ADR variable only within said PTDDC configured to increment that is maintained within each PTDDC in said serial daisy-chain to a value of zero in response to said DRIVE RESET command;
(d) issuing an IDENTIFY DEVICE command to said PTDDC daisy-chain via said HBA;
(e) determining when a PTDDC within said PTDDC serial daisy chain receiving said IDENTIFY DEVICE command has a local PTDDC_ADR variable that is equal to a value of zero, and if so, proceeding to step (h);
(f) sending said IDENTIFY DEVICE command to the current PTDDC in said PTDDC daisy-chain;
(g) returning data from the current PTDDC in said PTDDC daisy-chain and incrementing the value of said PTDDC_ADR local variable within said current PTDDC;
(h) determining when the first PTDDC receiving said IDENTIFY DEVICE command indicates the value of said local PTDDC_ADR variable is zero, then issuing said IDENTIFY DEVICE command to any disk drive attached to said first PTDDC, and incrementing said PTDDC_ADR local variable;
(i) passing control to said step (d) until PTDDCs searching is completed;
and
(2) configuring said PTDDC to enable said ESN to be readable via said PTI port.

24 more elements

Data storage architecture extension system and method

Life of this patent

Data storage architecture extension system and method

Life of this patent

Abstract

Claims20