JPH07334312A - Disk storage device - Google Patents

Abstract

PURPOSE:To shorten the processing time by enabling data to be transferred to a host from the HDD which gets ready for data transfer when a read instruction is executed for sectors other than a write bad sector even if the write bad sector is generated on the HDD. CONSTITUTION:A sector information recording circuit 8 monitors instruction/ execution result signal lines 101 and 102, generates sector management information from the write result of a write instruction, the start sector address of its writing, and the number of written sectors when the write instruction is executed, and records the sector management information in recording areas provided in a sector information recording part 7 by the sectors of HDDs 4 and 5. An HDD selecting circuit 9 decides whether the HDDs 4 and 5 are 'usable' or 'inhibited from being used' at the time of the read instruction execution by referring to the sector information recording part 7, and sends the decision result back to an interface control circuit 1. The interface control circuit 1 controls the issue of read instructions to HDD interface circuits 2 and 3 on the basis of the decision result of the HDD selecting circuit 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk storage device, and more particularly to a disk storage device using two disk drives.

[0002]

2. Description of the Related Art Conventionally, in a disk storage device of this type, as shown in FIGS. 5 and 6, writing of data to hard disk drives (hereinafter referred to as HDDs) 4 and 5 is normally completed, or HD indicating whether the process has terminated abnormally
Based on the HDD management information of the D information recording unit 10, the HDDs 4, 5
Data is being read from.

Referring to FIG. 5, the conventional disk storage device includes an interface control circuit 1, HDD interface circuits 2 and 3, HDDs 4 and 5, and a data path selector 6.
HDD information recording unit 10 and HDD information recording circuit 11
And an HDD selection circuit 12.

The interface control circuit 1 receives commands from a host (not shown) via the host data path 100, controls command execution in the disk storage device, transmits / receives data to / from the host, and reports execution results. And do.

The interface control circuit 1 receives the data received from the host at the time of executing the data write command from the HD.
Control is performed so that the data is written to D4 and D5, and that the data from the HDD, whichever of the HDDs 4 and 5 is ready for data transfer, is transferred to the host when the data read command is executed.

The HDD interface circuits 2 and 3 are commands / commands.
The command from the interface control circuit 1 is received via the execution result signal lines 101 and 102, and the HDD 4 of the command is received.
Issue 5 and perform detailed interface operations.

Further, when the HDD interface circuits 2 and 3 receive the data read command from the interface control circuit 1, when the HDDs 4 and 5 complete the data transfer preparation by executing the data read command, the data transfer to the data path selector 6 is performed. The ready signals 107 and 108 are transmitted.

The data path selector 6 connects the data path 111 with the interface control circuit 1 to the data paths 109, 110 with the HDD interface circuits 2, 3 when executing a data write command, respectively.

Further, the data path selector 6 receives the data transfer preparation completion signals 107 and 108 from the HDD interface circuits 2 and 3 at the time of executing the data read command, and the data of which of these signals becomes active earlier, The paths 109 and 110 are connected to the data path 111.

The HDD information recording unit 10 includes a signal / data line 1
When an address and data are sent from the HDD information recording circuit 11 via 15, the HD corresponding to this address
Write the data to the HDD management information area of D4, 5,
After that, the data is retained.

In the HDD information recording unit 10, as shown in FIG. 6, the memory addresses indicating the addresses of the HDD management information areas corresponding to the HDDs 4 and 5 are respectively HD-addressed.
The HDD management information of D4 and D5 is stored.

In FIG. 6, memory address' 100
0 '(' indicates that it is a hexadecimal number) is H
The address of the HDD management information area of the DD 4 is shown, and the memory address “1001” shows the address of the HDD management information area of the HDD 5.

Further, "00" of the HDD management information indicates that the data writing is completed normally by the previous data write command, and "01" of the HDD management information is abnormally completed by the previous data write command. It shows that it did.

When the command from the interface control circuit 1 is a data write command, the HDD information recording circuit 11 outputs H as an execution result indicating whether the data write command is normally or abnormally written to the HDDs 4, 5.
The DD management information is recorded in the HDD management information areas of the corresponding HDDs 4 and 5, respectively.

When the HDD selection circuit 12 receives the HDD selection instruction signal 117 from the interface control circuit 1, it goes high.
The HDD management information is read from the DD information recording unit 10. HD
The D selection circuit 12 reads H read from the HDD information recording unit 10.
Based on the DD management information, HDDs 4 and 5 that were performed before that
Determine whether there is an abnormal end in writing data to
The determination result is returned to the interface control circuit 1 as HDD selection information 118.

In the above disk storage device, when the data write command is received from the host, the interface control circuit 1 issues the data write command to the HDD interface circuits 2 and 3, respectively.

At this time, the interface control circuit 1 outputs the data path connect signal 114 to the data path selector 6, so that the data path selector 6 connects the data path 111 with the interface control circuit 1 to the HDD interface circuits 2 and 3. The data paths 109 and 110 are connected to each other.

As a result, the HDD interface circuits 2 and 3 and the data paths 109 and 110 are provided in the HDDs 4 and 5.
The same write data is written from the host respectively supplied via the.

If the writing of write data from the host to the HDD 4 ends normally and the writing of write data from the host to the HDD 5 ends abnormally, the HD
The D information recording circuit 11 outputs the execution result of the data write command to the HDDs 4 and 5 to the command / execution result signal lines 101 and 10.
Get from 2.

At this time, the HDD information recording circuit 11 is HD
HD with memory address '1000' assigned to D4
D management information is read once and it is confirmed that it is '00' (normal end).

After confirming the HDD management information corresponding to the HDD 4, the HDD information recording circuit 11 writes "00" (normal end) as HDD management information in the HDD management information area of the HDD 4.

Further, the HDD information recording circuit 11 includes the HDD 5
Since the data writing to the
HD with memory address '1001' assigned to D5
Write "01" (abnormal end) in the HDD management information area of the HDD 4 without confirming the D management information.

If the HDD management information in the HDD management information areas of the HDDs 4 and 5 is already "01" (abnormal termination), even if the execution result of the latest data write command is normal termination, The HDD management information area is not updated.

As described above, in the disk storage device that manages the HDDs 4 and 5 and the contents of the HDD information recording circuit 11 are as shown in FIG. 6, when the interface control circuit 1 receives a data read command from the host, Prior to the execution of the data read command, the selection start instruction signal 117 to the HDD selection circuit 12 is activated in order to check whether the data can be read from the HDDs 4 and 5.

The HDD selection circuit 12 uses the H of the memory addresses "1000" and "1001" of the HDD information recording circuit 11.
The DD management information is read, and the HDD 4 whose HDD management information is “00” (normal termination) is “usable”, and the HDD 5 whose HDD management information is “01” (abnormal termination) is “prohibited”. The HDD selection information 118 to be returned is returned to the interface control circuit 1.

When the interface control circuit 1 receives the HDD selection information 118 from the HDD selection circuit 12, it issues a data read command to the HDD 4 via the HDD interface circuit 2 and the data path 109.

When the HDD 4 is ready for data transfer, the HDD interface circuit 2 activates the data transfer ready signal 107 to the data path selector 6.

When the data path selector 6 detects that the data transfer preparation completion signal 107 has become active,
The data path 109 and the data path 111 are connected, and HD
The data of D4 is made to flow to the interface control circuit 1 via the data paths 109 and 111. As a result, the data in the HDD 4 is sent to the host via the interface control circuit 1.

As described above, in the execution of the data read command from the host, it is checked whether the sector address requested by the host has an abnormal write in the past, and the HDD which has no abnormal write in the past is checked. Only the data read command is controlled to be issued.

In connection with the above technology, Japanese Patent Laid-Open No. 63-21
Japanese Patent No. 7411 discloses a technique of prohibiting the use of a disk device in which writing has not been normally completed.

[0031]

In the above-mentioned conventional disk storage device, HDD management information is recorded for each HDD, and it is judged whether or not the HDD can be used based on this HDD management information. Issue a data read command only.

Therefore, once a write error occurs in one of the HDDs, the original function of transferring data from the HDD, which is ready for data transfer to the host when the data read command is executed, to the host, and the processing time is lost. Cannot be shortened.

Therefore, an object of the present invention is to solve the above-mentioned problems, and even if a defective writing sector occurs in the HDD, data is transferred to a sector other than the defective writing sector earlier when the data read instruction is executed. HDD enabled
Another object of the present invention is to provide a disk storage device capable of transferring data from a disk to a host and shortening the processing time.

[0034]

DISCLOSURE OF THE INVENTION A disk storage device according to the present invention is a disk storage device including first and second disk storage media in which the same data is written by a write command, respectively. Holding means for holding the data write result by the write command for each sector of each of the two disk storage media, and a disk storage medium to which the read command is issued based on the contents of the holding means when the read command is executed. And a determining means.

Another disk storage device according to the present invention is, in addition to the above configuration, means for issuing the read command to the disk storage medium determined as the disk storage medium to which the read command should be issued by the determination means. In response to the read command, the first read data from the disk medium is selected as read data.

[0036]

When the data write command is executed, sector management information is generated from the data write result by the data write command, the start sector address and the write execution sector number included in the data write command, and the sector management information is recorded. I'll do it.

When a data read command is executed, the HDD is "enabled" or "disabled" based on the sector management information corresponding to the sector address information of the data read command.
Is determined, and the HDD for issuing the data read command is determined based on the determination result.

As a result, two H's are issued for a data read command targeting a sector other than a defective write sector.
It becomes possible to use DD.

Therefore, even if a bad-writing sector occurs in the HDD, the data from the HDD that has become capable of data transfer to the host other than the bad-writing sector can be transferred to the host sooner when the data read command is executed. Therefore, the processing time can be shortened.

[0040]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In the figure, a disk storage device according to an embodiment of the present invention includes an interface control circuit 1 and an HDD.
It is composed of interface circuits 2 and 3, HDDs 4 and 5, a data path selector 6, a sector information recording unit 7, a sector information recording circuit 8 and an HDD selection circuit 9.

The interface control circuit 1 has an interface function with a host (not shown) and a control function for issuing commands to the HDD interface circuits 2 and 3 and receiving execution results.

The interface control circuit 1 sends the access address information 103 and the selection start instruction signal 106 to the HDD selection circuit 9 and executes the HDD selection information from the HDD selection circuit 9 prior to the execution of the data read command from the host. It has a function of receiving 112 and controlling the issuing of a data read command to the HDD interface circuits 2 and 3 based on the HDD selection information 112.

The interface control circuit 1 further releases the data path connection clear signal 11 for releasing the data path connection once set to the data path selector 6 as necessary.
3, and the data path 111 and the data paths 109 and 110
It has a function of outputting the data path connect signal 114 for instructing the connection with each.

The HDD interface circuits 2 and 3 are HDDs.
It receives an instruction sent from the interface control circuit 1 to the HDDs 4 and 5, and executes a detailed interface operation with the HDDs 4 and 5 in response to the instruction.

Further, the HDD interface circuits 2 and 3 exchange write data and read data with the data path selector 6, and when the data read command is executed, the HDD interface circuits
When it becomes possible to transfer the read data from 4, 5, the data transfer preparation completion signal 107 to the data path selector 6,
Activate 108.

The HDDs 4 and 5 are connected to the HDD interface circuits 2 and 3, respectively, and exchange commands (including sector addresses), data, and execution results with the HDD interface circuits 2 and 3.

The data path selector 6 connects the interface control circuit 1 and the HDD interface circuits 2 and 3 to the data paths 109 and 110 and the data path 11 respectively.
1 is connected to each.

Further, the data path selector 6 receives the data transfer preparation completion signals 107 and 108 from the HDD interface circuits 2 and 3 at the time of executing the data read command, and the data of which of these signals becomes active earlier, The paths 109 and 110 are connected to the data path 111.

The connection between the data paths 109 and 110 and the data path 111 is continued until it is released by the data path connection clear signal 113 from the interface control circuit 1.

The sector information recording section 7 is a non-volatile memory circuit for recording sector management information in a recording area provided for each sector of the HDDs 4 and 5, and the signal / data line 1
The sector management information sent from the sector information recording circuit 8 via 04 is written in the recording area, and thereafter the sector management information is held.

If the sector information recording section 7 can hold the sector management information when the power is turned off,
It is also possible to use a memory circuit other than the non-volatile memory circuit.

The sector information recording section 7 is connected to the HDD selection circuit 9 via the signal / data line 105,
The sector management information stored in the sector information recording unit 7 is HD
It can be read by the D selection circuit 9.

The sector information recording circuit 8 monitors the instruction / execution result signal lines 101 and 102 between the interface control circuit 1 and the HDD interface circuits 2 and 3, and when the instruction from the interface control circuit 1 is a data write instruction. , Sector interface information is generated from the execution results from the HDD interface circuits 2 and 3, the start sector address and the number of write execution sectors included in the data write command from the interface control circuit 1, and the sector information is recorded as sector information. Record in Part 7.

When the HDD selection circuit 9 receives from the interface control circuit 1 the sector address information 103 for executing the data read command and the selection start instruction signal 106, H based on the sector management information read from the sector information recording unit 7.
Determine whether the DD4 or 5 is "available" or "use prohibited",
The determination result is returned to the interface control circuit 1 as HDD selection information 112.

FIG. 2 is a diagram showing the recorded contents of the sector information recording section 7 of FIG. In the figure, memory address '10
00 '(''indicates hexadecimal) is H
The 8-bit (bit 7 to bit 0) data designated by the memory address '1000' is assigned to the sector management information of each of the sector addresses 0 to 7 of the HDD 4, which indicates the start address of the sector information recording memory of the DD 4. .

The memory address "1001" is HD
It indicates the address of the sector information recording memory of D4, and the 8-bit data (bit 7 to bit 0) designated by the memory address '1001' is set to the sector address 8 of the HDD 4.
.About.15 assigned to each sector management information.

On the other hand, the memory address "A000" is HD
D5 shows the start address of the sector information recording memory,
8-bit data (bit 7 to bit 0) designated by the memory address “A000” is assigned to the sector management information of each of the sector addresses 0 to 7 of the HDD 5.

Also, the memory address'A001 'is HD
It indicates the address of the sector information recording memory of D5, and the 8-bit data (bit 7 to bit 0) specified by the memory address'A001 'is stored in the sector address 8 of the HDD 5.
.About.15 assigned to each sector management information.

Here, the sector with sector management information "0" indicates a defective write sector in which a write abnormality has occurred, and the sector with sector management information "1" indicates a normal write sector in which no write abnormality has occurred. There is. In FIG. 2, HDD4
It indicates that the sector addresses 2 and 3 are defective write sectors.

FIG. 3 is a timing chart showing the operation of writing data to the HDD according to the embodiment of the present invention.
FIG. 4 is a timing chart showing a data read operation from the HDD according to the embodiment of the present invention. These Figure 1
The operation of the embodiment of the present invention will be described with reference to FIGS.

First, data from the host is stored in the HDDs 4, 5
A procedure for recording the sector management information for each sector of the HDDs 4, 5 by this writing in the sector information recording unit 7 when writing to each will be described.

The interface control circuit 1 is designated by reference numeral a in FIG.
When the data write command is received from the host at the timing of 1, the data path connect signal 114 is output to the data path selector 6 at the timing of symbol a2 in FIG.

The data path selector 6 connects the data path 111 and the data paths 109 and 110 at the timing of "1" of the data path connect signal 114 shown by reference numeral a2 in FIG.

The interface control circuit 1 is designated by reference numeral a in FIG.
The instruction / execution result signal line 10 at the timing of 3, a4
A data write command is issued to the HDD interface circuits 2 and 3 via 1, 102.

The HDD interface circuits 2 and 3 are HDDs.
Data write commands are issued to 4 and 5, respectively. HDD4
Reference numeral 5 receives and writes the write data sent from the host through the HDD interface circuits 2 and 3 at the timing a5 in FIG. 3 at the timings a6 and a7 in FIG.

The execution results of the data write command in the HDDs 4 and 5 are at the timings a8 and a9 in FIG.
It is sent from the HDD interface circuits 2 and 3 to the interface control circuit 1.

The sector information recording circuit 8 monitors the data write command on the command / execution result signal lines 101 and 102 between the interface control circuit 1 and the HDD interface circuits 2 and 3 and the execution result of the data write command, The start sector address and the number of write execution sectors included in the data write command and the execution result from the HDD interface circuits 2 and 3 are fetched.

For example, the data write command from the host is for two sectors of the sector addresses 2 and 3 of the HDDs 4 and 5, respectively, and the execution result of the HDD 4 indicated by the timing a8 in FIG. 3 indicates abnormal termination. A case will be described in which the execution results of the HDD 5 indicated by the timing of the symbol a9 indicate the normal termination, respectively.

The sector information recording circuit 8 is designated by a11 in FIG.
At the timing of, the 8-bit data of the memory address '1000', which is respectively assigned to the management of the HDD 4 of the sector information recording unit 7, is temporarily read through the signal / data line 104.

Since the sector information recording circuit 8 has abnormally finished writing to the sector addresses 2 and 3 of the HDD 4, the bits 5 and 4 corresponding to the sector management information of the sector addresses 2 and 3 are set to "0", respectively. . After this, the sector information recording circuit 8 does not change the other bits and the memory address' 1
Write back to 000 '.

Similarly, the sector information recording circuit 8 stores the 8-bit data of the memory address "A000", which is allocated to the management of the HDD 5 of the sector information recording unit 7 through the signal / data line 104 at the timing of a11 in FIG. Is read once.

Since the sector information recording circuit 8 has normally completed writing to the sector addresses 2 and 3 of the HDD 5, the bits 5 and 4 corresponding to the sector management information of the sector addresses 2 and 3 are recorded.
To "1" respectively. After that, the sector information recording circuit 8 does not change the other bits, and the memory address'A00
Write back to 0 '.

In this case, the interface control circuit 1 outputs H
Since the execution result of the DD4 to the sector addresses 2 and 3 ends abnormally, and the execution result of the HDD 5 to the sector addresses 2 and 3 ends normally, the execution result of the sector addresses 2 and 3 to the host at the timing a10 in FIG. Notifies that the process completed normally.

It should be noted that the notification of the execution result to the host is sent to the two H
The abnormal end is notified only when both of the data writing to the DDs 4 and 5 are abnormally ended.

As described above, when writing data from the host to the two HDDs 4 and 5, the sector information recording circuit 8 normally sets the memory bits specified by the HDDs 4 and 5 and the sector address of the sector information recording unit 7 to normal. If it is completed, it is rewritten to "1" indicating a normally written sector, and if abnormally completed, it is rewritten to "0" indicating a badly written sector.

Next, the procedure for receiving a data read command from the host and referring to the sector management information to send data to the host using one of the HDDs 4 and 5 will be described.

The interface control circuit 1 is designated by reference numeral b in FIG.
When the data read command from the host is received at the timing of 1, the HDD selection circuit 9 uses the read start sector address and the read execution sector number included in the data read command from the host as the access address information 103 at the timing of symbol b2 in FIG. Send to.

The HDD selection circuit 9 outputs "1" of the selection start instruction signal 106 sent at the timing of the symbol b3 in FIG.
By referring to the sector information recording unit 7, the HDD selecting operation is started.

That is, when the HDD selection circuit 9 detects "1" in the selection start instruction signal 106, the read start sector address of the access address information 103 is set as the first address, and the read execution sector number of the access address information 103 is set at this address. For the sector address string up to the final address obtained by adding 1 and subtracting 1
The memory bits specified by the HDD numbers and sector addresses of DDs 4 and 5 are read from the sector information recording unit 7.

The HDD selection circuit 9 indicates that the HDD in which the sector management information corresponding to this sector address string is all "1" indicating normal writing is "usable", and "0" indicating defective writing sector even at one location. The interface control circuit 1 is notified of the HDD selection information 112 for prohibiting use of a certain HDD.

When a data read command is issued from the host at the timing of reference numeral b1 in FIG. 4, the start sector address is "2", and the read execution sector number is "2", the HDD selection circuit 9 determines the sector. H in the information recording unit 7
Memory address' 100 assigned to management of DD4
Bits 5 and 4 corresponding to sector addresses 2 and 3 of 0'and memory address'A0 assigned to management of HDD 5
Bits 5 and 4 corresponding to sector addresses 2 and 3 of 00 '
Inspect each.

Here, when the sector management information of the sector addresses 2 and 3 of the HDDs 4 and 5 has the contents as shown in FIG. 2, the HDD selection circuit 9 determines the sector addresses 2 and 3 of the HDD 4.
3 is recognized as a defective writing sector, and the HDD selection information 112 for making the HDD 4 “usable” and making the HDD 5 “usable” is notified to the interface control circuit 1 at the timing of the symbol b4 in FIG.

When the interface control circuit 1 receives the HDD selection information 112 from the HDD selection circuit 9, it sends a data path connection clear signal 113 to the data path selector 6 at the timing of the reference symbol b6 in FIG.

When the data path connection clear signal 113 becomes "1", the data path selector 6 disconnects the connection between the data path 111 from the interface control circuit 1 and the data paths 109 and 110 from the HDD interface circuits 2 and 3. .

Next, the interface control circuit 1 is the HDD
Based on the content of the selection information 112, a data read command is issued to the HDD interface circuit 3 and the HDD 5 at the timing of the symbol b8 in FIG.

When the HDD interface circuit 3 issues a data read command from the interface control circuit 1 to the HDD 5 and the HDD 5 is ready to transfer the read data,
The data transfer preparation completion signal 108 is sent to the data path selector 6 at the timing of the symbol b9 in FIG.

When the data path selector 6 detects that the data transfer preparation completion signal 108 from the HDD interface circuit 3 has become "1", it is the signal transmission source H.
The data path 110 from the DD interface circuit 3 is connected to the data path 111 from the interface control circuit 1.

As a result, the data path of HDD 5 → HDD interface circuit 3 → data path selector 6 → interface control circuit 1 → host is established, and the read data is sent to the host at the timing of the symbol b10 in FIG.

When the HDD 5 completes the execution of the data read command, the execution result is passed through the HDD interface circuit 3 and the command / execution result signal line 102 to the symbol b1 in FIG.
The interface control circuit 1 is notified at the timing of 4.

The interface control circuit 1 is designated by reference numeral b in FIG.
At a timing of 16, the host is notified of the execution result of the HDD 5 received from the HDD interface circuit 3, and the execution of the data read command is completed.

At this time, since the sector from which data is read to the HDD 4 is a defective write sector, the interface control circuit 1 does not issue a data read command to the HDD 4.

Next, the procedure for receiving a data read command from the host and referring to the sector management information to send the data to the host using one of the HDDs 4 and 5 whichever is ready for data transfer earlier explain.

The interface control circuit 1 is designated by reference numeral b in FIG.
When the data read command from the host is received at the timing of 1, the HDD selection circuit 9 uses the read start sector address and the read execution sector number included in the data read command from the host as the access address information 103 at the timing of symbol b2 in FIG. Send to.

The HDD selection circuit 9 sends "1" to the selection start instruction signal 106 sent at the timing indicated by reference sign b3 in FIG.
By referring to the sector information recording unit 7, the HDD selecting operation is started.

For example, when the read start sector address included in the data read command from the host is “6” and the read execution sector number is “2”, the HDD selection circuit 9 controls the HDD 4 in the sector information recording unit 7. Bits 1 and 0 corresponding to the sector addresses 6 and 7 of the allocated memory address “1000” and the sector addresses 6 and 7 of the memory address “A000” allocated to the management of the HDD 5.
Bits 1 and 0 corresponding to are respectively inspected.

Here, when the sector management information of the sector addresses 6 and 7 of the HDDs 4 and 5 has the contents as shown in FIG. 2, the HDD selection circuit 9 determines that both the sector addresses 6 and 7 of the HDDs 4 and 5 are normally written sectors. Recognize that there is, HDD
The HDD selection information 112 that makes both 4 and 5 “usable” is sent to the interface control circuit 1 at the timing of the symbol b4 in FIG.

When the interface control circuit 1 receives the HDD selection information 112 from the HDD selection circuit 9, it sends a data path connection clear signal 113 to the data path selector 6 at the timing indicated by reference sign b6 in FIG.

When the data path connection clear signal 113 becomes "1", the data path selector 6 disconnects the data path 111 from the interface control circuit 1 and the data paths 109 and 110 from the HDD interface circuits 2 and 3. .

Next, the interface control circuit 1 is the HDD
Reference characters b7 and b8 in FIG. 4 are selected based on the contents of the selection information 112.
HDD interface circuits 2, 3 and H at the timing of
A data read command is issued to each of DD4 and DD5.

The HDD interface circuits 2 and 3 send a data read command from the interface control circuit 1 to the HDD.
When the HDDs 4 and 5 are ready to transfer the read data in the HDDs 4 and 5, respectively, the data transfer preparation completion signals 107 and 108 are sent to the data path selector 6 at the timings b11 and b9 in FIG.

In this case, since the data transfer preparation completion signal 108 from the HDD interface circuit 3 is input earlier than the data transfer preparation completion signal 107 from the HDD interface circuit 2, the data path selector 6 causes the data transfer preparation completion signal 108. Is transmitted to the data path 110 from the HDD interface circuit 3 to the data path 111 from the interface control circuit 1.

As a result, a data path of HDD 5 → HDD interface circuit 3 → data path selector 6 → interface control circuit 1 → host is established, and the read data from the HDD 5 is sent to the host at the timing b10 in FIG. .

When the HDD 5 completes the execution of the data read instruction, the execution result is passed through the HDD interface circuit 3 and the instruction / execution result signal line 102 to the symbol b1 in FIG.
The interface control circuit 1 is notified at the timing of 4.

The interface control circuit 1 is designated by reference numeral b in FIG.
At a timing of 16, the host is notified of the execution result of the HDD 5 received from the HDD interface circuit 3, and the execution of the data read command is completed. At this time, the read data read from the HDD 4 remains in the data path selector 6.

As described above, in one embodiment of the present invention, two HDDs are used when writing the write data from the host.
Even if one of four or five defective write sectors occurs,
In a data read command targeting a sector other than the defective write sector, a data read command is issued to each of the two HDDs 4 and 5.

Therefore, the HD in which the defective write sector has occurred
Without unconditionally prohibiting the use of D, the original function of transferring the data from the HDD, which is ready for data transfer to the host, to the host other than the defective write sector when the data read command is executed, works. Therefore, the processing time can be shortened.

As described above, when the write data from the host is written to the two HDDs 4 and 5, even if one of the defective write sectors occurs, the entire HDD where the defective write sector occurs is prohibited. By using two HDDs 4 and 5 for a data read command targeting a sector excluding the defective write sector, even if a defective write sector occurs in the HDD, it is not included in the defective write sector. The data from the HDD capable of transferring data to the sector can be transferred to the host at the earliest when the data read command is executed, and a high-speed disk storage device capable of shortening the processing time can be provided. .

[0109]

As described above, according to the present invention, the data write result of the write command is held for each sector of each of the first and second disk storage media in which the same data is written by the write command. By determining the disk storage medium to which the read command should be issued based on the contents held when the read command is executed, even if a bad write sector occurs on the disk storage medium, sectors other than the bad write sector are There is an effect that data from the disk storage medium, which can be transferred earlier at the time of the read command, can be transferred to the host, and the processing time can be shortened.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing recorded contents of a sector information recording section of FIG.

FIG. 3 is a timing chart showing the operation of writing data to the HDD according to the embodiment of the present invention.

FIG. 4 is a timing chart showing a data read operation from an HDD according to an embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a conventional example.

FIG. 6 is a diagram showing recorded contents of an HDD information recording unit of FIG.

[Explanation of symbols]

 1 Interface Control Circuit 2, 3 HDD Interface Circuit 4, 5 Hard Disk Drive 6 Data Path Selector 7 Sector Information Recording Section 8 Sector Information Recording Circuit 9 HDD Selection Circuit

Claims (3)

[Claims] 1. A disk storage device including first and second disk storage media to which the same data is respectively written by a write command, wherein the writing is performed for each sector of each of the first and second disk storage media. Disk storage comprising holding means for holding a data write result by an instruction and deciding means for deciding a disk storage medium to which the read instruction should be issued based on the contents of the holding means when a read instruction is executed. apparatus. 2. The disk storage according to claim 1, wherein the determining unit is configured to determine a disk storage medium showing a normal write result as a disk storage medium to which the read command should be issued. apparatus. 3. The means for issuing the read command to the disk storage medium determined as the disk storage medium to which the read command is to be issued by the determining means, and the disk medium first in response to the read command. 3. The disk storage device according to claim 1, further comprising means for selecting read data as read data.