JPH05224829A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To detect write abnormality in a short time by reading out data within a range wherein inspection is required according to a stored address when the magnetic disk is started up after a recovery from a power failure. CONSTITUTION:This magnetic disk device is equipped with an address recording part 7 consisting of a nonvolatile memory wherein the physical address of data written on a medium is recorded, a state recording part 8 which records the generation state of the write abnormality due to the power failure and informs a host device 1 of the generation state, and a write abnormality detection part 9 which reads out the data on the address recorded in the address recording part 7, detects whether or not there is the write abnormality, and informs the state recording part 8 of the detection result. When the magnetic disk device 3 is started up after the recovery from the power failure, a main control part 4 reads out data on all addresses written in the address recording part 7 and confirms whether or not there is a read error to detect the occurrence of the write abnormality, and the detection result is recorded in the state recording part 8 and reported to the host device 1 through a magnetic disk controller 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and more particularly to detection and prevention of abnormal writing during a power failure.

[0002]

2. Description of the Related Art Conventionally, in a magnetic disk device, if a power failure occurs during writing, the presence or absence of a write error can be detected in a short time after recovery from the power failure (hereinafter referred to as power recovery), and further prevent abnormal write. There was no way to do it, and the entire surface was read to check if there was any data abnormality.

[0003]

The above-described conventional magnetic disk device does not have a function of easily detecting the fact that a write abnormality occurs due to a power failure at the time of writing. Since there is only a method for detecting a write abnormality only to check whether or not there is any abnormality, there is a drawback in that detection takes time.

An object of the present invention is to provide a magnetic disk drive capable of detecting the occurrence of a write error associated with a power failure in a short time after power recovery and reporting it to a host device, and further stopping the write in the event of a power failure. is there.

[0005]

According to a first magnetic disk device of the present invention, an address recording section composed of a non-volatile memory in which a physical address of data written on a medium is recorded, and a write abnormality occurrence state due to a power failure. The status recording section that records and notifies the upper-level device and the address data recorded in the address recording section at the time of start-up after power recovery, reads the presence or absence of a write error, and outputs the detection result to the status recording section. It has a writing abnormality detection unit for notifying. In the second magnetic disk device of the present invention, the state recording unit is composed of a non-volatile memory, and further includes a function of recording the occurrence and recovery of a power failure and the possibility of a write error occurrence due to the power failure. Notify the department and stop writing new data, judge whether there is a possibility that a write error will occur in the data being written at the time of detection after a power failure, and if there is a possibility that an error has occurred, Also, when the power failure recovers during writing of the data, a power failure detecting section that notifies the status recording section to that effect, and the possibility that the writing error has occurred in the status recording section or the power failure recovers during data writing When there is a record to that effect, there is an abnormality detection starting unit that starts the write abnormality detecting unit.

In the address recording section of the first or second magnetic disk device of the present invention, a plurality of addresses are cyclically recorded and are constantly updated to the latest address.

[0007]

In the first magnetic disk drive of the present invention,
The address of the data written on the medium is recorded in the address recording section consisting of a non-volatile memory, so in the event of a power failure, the range that needs to be checked based on the recorded address at startup after power recovery. It is possible to read only the data of, and it is possible to detect a write error by confirming a read error in a short time.

In the second magnetic disk device of the present invention, a power failure detecting section and an abnormality detecting starting section are further provided, and when a power failure is detected, a new writing operation of data is stopped, and when the power failure is detected, the data is written. If writing is in progress, the writing does not occur due to the writing ending during the normal operation maintaining time, or the data is not written during the normal operating maintaining time and the power supply is cut off during the writing to write data. If there is a possibility that an abnormality will occur, determine the possibility, and if there is a possibility, record that fact, and if the power failure is momentary and the power is restored during writing during the normal operation maintenance time, record that fact. Therefore, in these cases, when power is restored or after that, read error check is performed based on the recorded address in the same manner as above to detect the presence or absence of a write error. Possible it is.

Furthermore, since the address recorded by the address recording unit is updated to the plurality of latest addresses, the capacity of the address recording unit can be determined in accordance with the transient time of power failure or power recovery.

[0010]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is an overall block diagram of an embodiment of a first magnetic disk device of the present invention, and FIG. 2 is an explanatory view of an address recording section in the embodiment of the first magnetic disk device of the present invention. 3 is an explanatory diagram showing a temporal relationship between a power failure and the operation of the magnetic disk device.

In the magnetic disk device 3 of the first embodiment shown in FIG. 1, in addition to the main control unit 4, the head unit 5 and the power supply unit 6, an address recording unit 7 and a status recording unit 8 each composed of a non-volatile memory are provided. Is equipped with.

The data sent from the host device 1 is output to the magnetic disk device 3 via the magnetic disk control device 2. The main control unit 4 of the magnetic disk device 3 converts the data sent from the magnetic disk control device 2 into a format for recording on the medium surface, and outputs it as an analog write signal to the head unit 5. At the same time, the write physical address (head number, cylinder number, sector number) is output to the head unit 5, and the head is positioned. This write physical address is also output to and recorded in the address recording unit 7. The operation of the magnetic disk device 3 at the time of power failure will be described with reference to FIG. 3. Even if the power failure occurs at time 0, the magnetic disk device 3 operates normally due to the electric charge stored in the power supply unit 6 until t ₁ hours elapse. Is maintained and the operation is stopped at time t ₂ when the discharge ends. The time from t ₁ to t ₂ is in a transient state, and this time is the magnetic disk device 3 when a power failure occurs.
It changes depending on factors such as the operating state of AC and the AC input voltage value. If the magnetic disk device 3 is performing the write operation during the time from t ₁ to t ₂ , the operation is stopped during the write, and a write error occurs.

From the above, if the storage capacity of the address recording unit 7 is set to be larger than the value that covers the maximum number of sectors in which the magnetic disk device 3 may write an address during the time from t ₁ to t _2. All physical addresses where abnormal data may be recorded are recorded in the address recording unit 7. In the present embodiment, as shown in FIG. 2, the address recording unit 7 is constantly overwritten with some of the latest addresses and updated.

When the magnetic disk device 3 is started up at the time of power recovery, the main control unit 4 reads the data of all the addresses written in the address recording unit 7 and confirms whether or not there is a read error, thereby confirming the write error. Detect occurrence. The detection result of the write abnormality is recorded in the state recording unit 8 and is notified to the host device 1 via the magnetic disk control device 2.

FIG. 4 is an overall block diagram of an embodiment of the second magnetic disk device of the present invention.

The magnetic disk device shown in FIG. 4 is provided with a power failure detecting section 10 and an abnormality detecting starting section 11 in the configuration of FIG.
After the power failure is detected, the write operation is stopped to suppress the write error and the file protection function is enhanced. In this case, when there is a possibility that an error may have occurred in the data that was being written at the time of power failure, and when the power is restored during the writing, the write error detection unit 9 is referred to by referring to the record
The abnormality detection starting part 11 which starts is added. In this case, the state recording unit 8 is also composed of a non-volatile memory.

When a power failure is detected, the power failure detecting section 10 notifies the state recording section 8 that a power failure has occurred, and requests the main control section 4 to reject the subsequent write request. If a write operation is in progress at the time of power failure, the maximum value of the time required to complete the write is estimated and compared with the normal operation maintenance time (time from 0 to t ₁ in FIG. 3) described above, and the write error is detected. Determine whether it is possible. That is, if it is estimated that the writing is surely completed within the normal operation maintaining time, it is judged that the write abnormality does not occur, but if it is estimated that the normal operation maintaining time elapses during the writing, the write abnormality occurs. It judges that there is a possibility and notifies the state recording unit 8 of that fact. Even when it is determined that the write abnormality does not occur, when the power is restored for a short time (within the time from 0 to t ₁ in FIG. 3) and the power is restored during writing, the fact is notified to the state recording unit 8. Notice.

The abnormality detection starting unit 11 refers to the state recording unit 8 at the time of power recovery, and if it is recorded that a writing error may occur, the abnormality detection starting unit 11 records it in the address recording unit 7 as in the case of the first embodiment. The data at the specified address is read and the read error confirmation processing is performed. Also, if the fact that the power failure has been recovered is recorded during the writing during the normal operation maintenance time, after the sufficient time that the influence of the power failure has disappeared, the write data in the transient time after power recovery is also read in the same way. Perform error confirmation processing.

[0020]

As described above, according to the present invention, the address written in the medium is recorded, and when there is a power failure, the data is read based on the recorded address to detect an abnormality in writing, By recording and reporting to the host device, it is possible to detect the writing error due to power failure in a short time after power recovery, and by adding the function to stop writing when power failure is detected, When the power failure occurs during the writing operation, even if the power failure is momentary, if there is a possibility of a write accident, the read error confirmation processing is performed to improve the reliability of the data. It has the effect of strengthening the file protection function.

Further, by recording a plurality of updated latest addresses in the address recording section, the data is read out by limiting to the data in which the writing error may occur due to the power failure. There is an effect that the detection can be easily performed in a short time.

[Brief description of drawings]

FIG. 1 is an overall block diagram of an embodiment of a first magnetic disk device of the present invention.

FIG. 2 is an explanatory diagram of an address recording section in an embodiment of the first and second magnetic disk devices of the present invention.

FIG. 3 is an explanatory diagram showing a temporal relationship between a power failure and the operation of the magnetic disk device.

FIG. 4 is an overall block diagram of an embodiment of a second magnetic disk device of the present invention.

[Explanation of Codes] 1 host device 2 magnetic disk control device 3 magnetic disk device 4 main control unit 5 head unit 6 power supply unit 7 address recording unit 8 status recording unit 9 write error detection unit 10 power failure detection unit 11 error detection activation unit

Claims (3)

[Claims] 1. A status recording unit for recording a physical address of data written on a medium in a magnetic disk device, the address recording unit comprising a non-volatile memory, and a condition for recording a write abnormality due to a power failure and notifying a host device. Section, and a write abnormality detection section that reads out the data of the address recorded in the address recording section at the time of start-up after recovery from a power failure, detects the presence or absence of a write abnormality, and notifies the state recording section of the detection result. A magnetic disk device characterized by the above. 2. The state recording unit is composed of a non-volatile memory, and further includes a function of recording a power failure and its recovery, and a possibility of occurrence of a write error due to the power failure, and when the power failure is detected, the status recording unit is notified. Stop writing new data, judge whether there is a possibility that a write error will occur in the data being written when the power failure is detected, and if there is a possibility of error,
Further, when the power failure is recovered during writing of the data, a power failure detecting section for notifying the status recording section of that fact, and the status recording section indicating that the writing error may occur or the power failure recovered during data writing 2. The magnetic disk device according to claim 1, further comprising an abnormality detection activation unit that activates the write abnormality detection unit when there is a record to that effect. 3. The magnetic disk device according to claim 1, wherein the address recording unit cyclically records a plurality of addresses and is constantly updated to the latest address.