Direct data file storage implementation techniques in flash memories

• US 20060184722A1
• Filed: 01/26/2006
• Published: 08/17/2006
• Est. Priority Date: 02/16/2005
• Status: Abandoned Application

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Inventors: Sinclair, Alan W.
• Application Number:
  US11/342,168
• Publication Number:
  US 20060184722A1
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

Host system data files are written directly to a large erase block flash memory system with a unique identification of each file and offsets of data within the file but without the use of any intermediate logical addresses or a virtual address space for the memory. Directory information of where the files are stored in the memory is maintained within the memory system by its controller, rather than by the host. The file based interface between the host and memory systems allows the memory system controller to utilize the data storage blocks within the memory with increased efficiency.

Claims

1. A mass storage system, comprising:

an array of non-volatile charge storage semiconductor memory cells organized into blocks that are erased prior to any new data being written therein and which individually have a capacity of storing multiple units of received data that individually include at least 512 bytes of data,

a controller connected with the memory cell array and adapted to receive data with a logical address including a unique file identification and offsets of data within the identified file to program the received data at physical addresses within the blocks of memory cells, and which further operates to maintain a plurality of records of the programmed data for the individual files that identify groups of variable amounts of data making up the file, data within the groups individually having both contiguous logical offset addresses and contiguous physical addresses, wherein the individual records include at least a beginning logical offset address and a beginning physical address of the data within the group.

2. The mass storage system of claim 1, wherein the individual records additionally includes length of the data within the group.

3. The method of claim 1, wherein the memory cell array includes a number of memory cells sufficient to store at least 256 megabytes of data.

4. The method of claim 1, wherein the individual unit of data contains at least 1024 bytes of data.

5. A mass storage system, comprising:

an array of non-volatile charge storage semiconductor memory cells organized into blocks that are erased prior to any new data being written therein and which individually have a capacity of storing at least 1024 bytes of received data,

a controller connected with the memory cell array and adapted to receive data with a logical address including a unique file identification and offsets of data within the identified file to program the received data at physical addresses within the blocks of memory cells as defined groups of data individually having a size equal to or less that the capacity of the individual memory cell blocks and containing data having continuous logical and physical addresses, and

a table capable of storing records of individual groups of data stored in the memory cell array, individual data records for a file of data including a starting logical offset address, a starting physical address and length of the data group.

6. The mass storage system of claim 5, wherein the starting physical address of the individual data records includes an identification of a block of memory cells and a byte location within the identified block.