ERROR DETECTION DEVICE

• US 20080320376A1
• Filed: 08/28/2008
• Published: 12/25/2008
• Est. Priority Date: 02/28/2006
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: UNNO, Hideyuki
• Granted Patent: US 8,196,028 B2
• Time in Patent Office: Days
• US Class Current: 714/819
• CPC Class Codes: G06F 11/073 in a memory management context, e.g. virtual memory or cache management memory management G06F12/00; testing of static memory units G11C29/00
• CPC Class Codes: G06F 11/0763 by bit configuration check, e.g. of formats or tags
• CPC Class Codes: G06F 11/10 Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's
• CPC Class Codes: G06F 12/0802 Addressing of a memory level in which the access to the desired data or data block requires associative addressing means, e.g. caches

Abstract

A data buffer control unit obtains data from a cache according to a command retained in a command queue retaining a command(s) for reading data from the cache, and a magic ID generation circuit generates a magic ID. The data buffer control unit assigns the data obtained from the cache with the magic ID, writes the assigned data to a data buffer, and returns the magic ID to the command queue. When the data buffer control unit receives a read request and the magic ID which is returned to the command queue, it reads the data, which corresponds to the read request, from the command queue and compares the magic ID assigned in the read data and the received magic ID. If the two magic IDs compared by the data buffer control unit are not identical, a packet generator detects an error and reports the error to a host.

Claims

1. An error detection device, comprising:

a command retention unit for retaining a command to read data from a storage apparatus;

a first process unit for obtaining data from the storage apparatus in accordance with a command retained in the command retention unit and generating identification information;

a second process unit for assigning data obtained from the storage apparatus with the identification information, writing the assigned data to a temporary storage device, and returning the identification information to the command retention unit;

a comparison unit for reading corresponding data from the temporary storage device in accordance with a read command when receiving the read request corresponding to the command retained in the command retention unit and the identification information returned thereto, and for making a comparison between the identification information assigned in the read data and the received identification information;

a transmission unit for transmitting data which is read from the temporary storage device in accordance with the read request; and

a report unit for sending an error report to a host in a case other than the case in which two pieces of identification information compared by the comparison unit are identical to each other.

2. The error detection device according to claim 1, wherein

said comparison unit receives, by way of said transmission unit, said read request and said identification information which is returned to said command retention unit.

3. The error detection device according to claim 1, wherein

said transmission unit transmits data which is read from said temporary storage device to a transmission destination only when two pieces of identification information compared by the comparison unit are identical to each other.

4. The error detection device according to claim 1, wherein

said identification information is comprised of sequential numbers in ascending order or descending order.

5. The error detection device according to claim 1, wherein

said identification information is comprised of pseudorandom numbers.

6. The error detection device according to claim 1, wherein

said identification information is generated by using a hash function.

7. The error detection device according to claim 1, wherein

said identification information is generated on the basis of storage destination information indicating a storage destination, in said temporary storage device, of data

8. The error detection device according to claim 1, wherein

said command retention unit, first process unit, second process unit, comparison unit and transmission unit are equipped on a single CPU chip.

9. The error detection device according to claim 1 is applied to a network device for transferring data which is received by way of a network to another device.

10. An error detection method, comprising:

retaining a command for reading data from a storage apparatus;

obtaining data from the storage apparatus in accordance with the retained command and generating identification information;

assigning data obtained from the storage apparatus with the identification information, writing the assigned data to a temporary storage device, and returning the identification information to a unit retaining the command;

reading corresponding data from the temporary storage device in accordance with a read command when the read request corresponding to the retained command and the identification information returned to a unit retaining the command are received, and making a comparison between the identification information assigned in the read data and the received identification information; and

sending an error report to a host in a case other than the case in which two pieces of identification information compared by comparison unit are identical to each other.