JPH01106132A - Data processor - Google Patents

Abstract

PURPOSE:To ensure the recovery of data at the second application of a power supply even in case the power supply is cut off while the data are written into a disk storage device by storing previously the write data into a memory backed up by the power supply. CONSTITUTION:A flag is read out during a write mode of a memory backed up by a power supply and an ON or OFF state of the flag is decided. In an ON state of the flag, it is decided that the power supply is cut off during a write mode of a disk storage device. Then the data stored in said memory backed up by a power supply is written again into the disk storage device. While in an OFF state of the flag during a write mode, a sector corresponding to the record data to be written is read out of the disk storage device to the memory backed up by a power supply. Then the record data is read out of the storage device and stored for update into a position corresponding to the sector data on the memory backed up by a power supply. The updated sector data is written into the disk storage device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data processing apparatus using a computer device, and particularly to a data processing apparatus suitable for protecting data in a disk storage device.

[Conventional technology]

In computer equipment equipped with a disk storage device, if the power is cut off while data is being written to the disk storage device, not only the data being written will be destroyed, but also the data before and after it. There was sex.

Regarding this type of technology, Japanese Patent Application Laid-Open No. 59-35
No. 50 and Japanese Unexamined Patent Publication No. 59-9564.

[Problem that the invention seeks to solve]

Conventional computer equipment does not take into account the fact that the power may be cut off while data is being written to the disk storage device, which can destroy the data being written and also damage the data before and after the written data. The problem was that there was a possibility that

An object of the present invention is to provide a data processing device that recovers the written data and the data before and after it when the power is turned on again even if the power is turned off while writing data to a disk storage device. It is in.

[Means for solving problems]

The above purpose is to write data to a disk storage device.
This is achieved by storing the write data and the data before and after it in advance in a storage device with power backup.

[Effect]

When writing data to a disk storage device, first convert the data you are trying to write into a management unit of the disk storage device, check which part it corresponds to, read the corresponding management unit to the storage device with power backup, and write the data to the storage device with power backup. The data is updated above, and then written to the disk storage device for each management unit of the disk storage device. Even if the power is turned off at this time, the storage device with power backup will still store data for the management unit of the disk storage device, so when the power is turned on again, the data will be transferred from the storage device with power backup to the disk storage device again. Once written, the data will be recovered.

〔Example〕

An embodiment of the present invention shown in the drawings will be described below.

FIG. 2 is a block diagram showing the overall configuration of a data processing device to which the present invention is applied. The CPU is a processing device that reads data from the disk storage device DM or writes data stored in the storage device RAM, etc., based on a program stored in the storage device RAM and as needed.

The storage device SRAM with power backup is functionally equivalent to the storage device RAM, but it is a nonvolatile storage device that has power backup and does not lose its stored contents even when the power is turned off.

FIG. 3 shows the software configuration of the data processing apparatus shown in this embodiment. The operating system O5 is a management program that receives various hardware operation instructions issued by various processing programs and processes all hardware operations at once. The data protection means indicated by DP is the main part of this embodiment, and the data protection means is the main part of this embodiment.
When writing data to M, a predetermined function is achieved by issuing a data write request from the processing program AP to the data protection means DP according to a predetermined procedure. Steps 1 and 2 show the flow of processing when a data write request is issued from the processing program AP to the disk storage device DM. Step 3 shows the flow of processing when another hardware operation request is issued from the processing program AP.

FIG. 1 shows the configuration of the storage area of the disk storage device DM used in this embodiment. Si Si O.

The sector indicated by is a physical management unit, and the operating system DS communicates with the disk storage device DM in this unit. A record indicated by r j+ r j+1, etc. is a logical management unit, and its length can be freely determined by various processing programs. Conversion between a logical unit, a record, and a physical unit, a sector, is normally performed by the operating system O3, which is a management program.

In implementing the data protection means DP shown in Figure 4,
Storage device RAM and storage device SR with power backup
Set up various storage units in AM.

FIG. 8 shows storage units for setting the storage device RAM, and these storage units will be explained below. The sector length SL is a physical unit managed by the disk storage device, and is the length of the lid. The record length RL is the length of a record, which is a logical storage unit handled by various processing programs. Record NaRNO is the position from the beginning of the record that the processing program AP is attempting to write to the disk storage device DM.

The record buffer RBuFF is a disk storage device DM.
This is a buffer for storing the contents of the record that is about to be written to. FIG. 9 shows storage units set in the storage device SRAM with power backup, and these storage units will be explained below.

The writing flag WF is a flag indicating whether or not data is currently being written to the disk storage device DM. Valid sector number
, S NO indicates the position from the beginning of the sector data stored in the sector buffer 5BuFF. The number of effective sectors 5CNT is the sector buffer 5BuFF.
Indicates the number of sector data stored in. The sector buffer 5BuFF is a buffer for storing the contents of sector data to be written to the disk storage device DM.

The data protection means DP will be explained below with reference to these. FIG. 4 shows a flowchart of the data protection means DP. Here, before the data protection means is executed, the sector length SL and record length R of the storage device RAM are set in advance.
It is assumed that the record NαRNO is set to a default value by the processing program AP. In addition, storage device R
It is assumed that record data to be written to the disk storage device DM is set in the record buffer RBuFF of the AM by the processing program AP. First, in step 10, the writing flag WF of the storage device SRAM with power backup is read out, and it is determined whether the flag is ON or not. When this flag is ON, it indicates that the power was cut off while writing to the disk storage device DM last time, so in step 20, the valid sectors Na5NO and the number of valid sectors 5CN stored in the storage device SRAM with power backup are
The sector data stored in the sector buffer 5BuFF is written to the disk storage device DM again using T.

After that, the process returns to the current write process. If the writing flag WF is OFF in step 10, the previous writing process has ended normally, so step 30 is executed. In step 30, the sector length SL, record length RL, and record N11RNO stored in the storage device RAM are
is used to calculate which sector the record data to be written corresponds to and store it in a valid sector NLIS N O of the storage device SRAM with power backup.

Next, in step 40, it is determined whether the record to be written spans between sectors. If the data spans between sectors, in step 50, the number of effective sectors 5CNT of the storage device SRAM with power backup is set to 2. If it does not span between sectors, in step 60 the effective number of sectors of the storage device SRAM with power backup is 5.
Set CNT to 1. Next, in step 70, the sector corresponding to the record data to be written is transferred from the disk storage device DM to the storage device SRA with power backup.
Read into sector buffer 5BuFF of M. Next, in step 80, the record buffer RBuF of the storage device RAM is
The record data is read from F, and the storage device SRAM with power backup is read out in step 70.

The sector data is stored in the corresponding position of the sector buffer 5BuFF, and the sector data is updated.

Next, in step 90, the storage device SR with power backup
Valid sector N (L S N O,
Using the effective sector number 5CNT, the updated sector buffer 5BuFF is written to the disk storage device DM.

Hereinafter, each means executed in each step shown in FIG. 4 will be explained in detail. 6 is a flowchart showing details of the sector floor acquisition processing means 5ECCAL executed in step 30 of FIG. 5. FIG. In step 10, the record No. RN O stored in the storage device RAM is multiplied by the record length RL, and the quotient is divided by the sector length SL to determine the sector Nα corresponding to the record that the processing program AP is about to write. as the effective sector number of the storage device sRAM with power backup.

Store in SNO.

FIG. 6 is a flowchart showing details of the sector write processing means 5ECWR executed in step 20 and step 90 of FIG. In order to indicate that the sector write process has started in step 10, the storage device SR with power backup
Turn on the AM0 writing flag WF. In step 20, data is written from the sector buffer 5BuFF to the disk storage device DM by the number of effective sectors NαSNO stored in the storage device SRAM with power backup. In step 30, the writing flag WF of the storage device with power backup SRAM0 is turned OFF to indicate that the sector writing process has ended normally.

FIG. 7 is a flowchart showing details of the sector reading processing means 5ECRD executed in step 70 of FIG. In step 10, the storage device SRAM with power backup
Valid sector number stored in .

Disk storage device D with effective sector count 5CNT from SNO
Read data from M into sector buffer 5BuFF.

As is clear from the above description, according to this embodiment, even if the power is cut off while writing to the disk storage device, the data can be restored normally without being destroyed, and data protection is realized. be able to.

〔Effect of the invention〕

According to the present invention, even if the power is cut off while data is being written to a disk storage device, the data can be recovered, thereby improving the reliability of the data.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a disk storage device, FIG. 2 is a configuration diagram of a processing device of this embodiment, FIG. 3 is a software configuration diagram of this embodiment, and FIG. 4 is a flowchart of data protection means. FIG. 5 is a flowchart of the sector acquisition processing means, FIG. 6 is a flowchart of the sector write processing means, FIG. 7 is a flowchart of the sector read processing means, and FIG. 8 shows the storage contents of the storage device. 9 are diagrams showing the storage contents of the storage device with power backup. cpu...processing device, DM...disk storage device,
RAM...Storage device, SRAM...Storage device with power backup. Agent Patent Attorney Masami Akimoto

Claims (1)

[Claims] 1. A first memory for storing programs and data, and a CPU that processes and exchanges data with this memory;
In a data processing device having a disk memory and a buffer interposed between the disk memory and a CPU for temporarily storing data, the buffer is configured of a non-volatile memory, and the buffer is provided on the buffer. A flag storage section is provided that is turned ON when data is written to the disk memory and turned OFF when writing is completed, and if the flag storage section is ON when the disk memory is accessed, the previous data on the buffer is transferred to the disk memory. A data processing device that sends the current data to the disk memory and continues to send the current data, and if it is OFF, sends the current data to the disk memory.