HK1114461B - Information recording/reproducing apparatus and method - Google Patents

Description

Information recording/reproducing apparatus and method

The present application is a divisional application of application No. 200580025710.9 entitled "information recording medium, recording/reproducing apparatus, and recording/reproducing method" filed on 7/18/2005 by the office of intellectual property rights of china.

Technical Field

Aspects of the present invention relate to an information recording medium, and more particularly, to an information recording medium, a recording/reproducing apparatus, and a recording/reproducing method, by which data replacement when Logical Overwrite (LOW) occurs in a spare area or a user data area can be effectively managed.

Background

Rewritable information recording media typically include a spare area in a portion of the data area to enable defect management. In other words, when defect data is detected while user data is recorded in a user data area (an area remaining in the data area excluding the spare area) or while data recorded in the user data area is reproduced, replacement of the defect data is recorded in the spare area.

In write-once information recording media, this defect management method is applied to Logical Overwrite (LOW). Logical overwrite is a technique that produces the same effect when data is overwritten to a write-once information recording medium. In other words, in order to update data already recorded in the user data area, replacement data replacing the recorded data is recorded in the spare area, taking the recorded data as defect data. Therefore, although the physical address of the replacement data is different from the physical address of the recorded data, the logical address of the data recorded in the user data area is still used as the logical address of the replacement data. Accordingly, since the host accesses only the logical address, the host can detect that the data already recorded in the user data area is overwritten. Thus, the host can easily manage the write-once information recording medium.

However, a method of recording update data in an unrecorded area in a user data area instead of a spare area and providing replacement information (i.e., defect entry information) has been used to implement defect management-based LOW to fully utilize the capacity of the write-once information recording medium.

Such replacement recording in an unrecorded area of the user data area for implementing LOW complicates the recovery of replacement data destroyed due to a power failure or an error of replacement information. In the case where an area on which replacement of defect data or replacement for LOW is recorded is limited to a spare area, a replacement block exists only in the spare area. Accordingly, the replacement data can be restored by searching for the replacement block only in a separate spare area. However, when the user data area is used as an area in which replacement of defect data or replacement for LOW is recorded, it is necessary to divide blocks recorded in the user area on the information recording medium into a user block (original data block not replaced by a new block) and a replacement block. In addition, in the case where replacement data is recorded in the user data area, a predetermined rule is required to easily recover the replacement data.

In summary, in the case where replacement of user data for LOW can be recorded not only in a spare area but also in a user data area, a user block cannot be distinguished from a replacement block because there is no physical boundary between a physical area in which the user block is recorded and a physical area in which the replacement block is recorded. In particular, in the case where the user block is replaced with the replacement block and the replacement block is replaced again, the last replacement block cannot be identified. Finally, in response to a command to record data in a space (space) in which data is physically recorded but data is not logically recorded, the drive system cannot distinguish between a case where a replacement block is replaced again and a case where a block is recorded in the physically unrecorded space.

The above-mentioned conventional problem will now be described with reference to fig. 1A to 1C. Referring to fig. 1A, in case 1, a first update of original data a is recorded in track #1 and a second update is recorded in track # 2. In case 2, a first update of the original data a is recorded in track #2 and a second update is recorded in track # 1. In case 3, a first update of the original data a is recorded in the track #2 and a second update is recorded in the spare area SA. In case 4, a first update of the original data a is recorded in the spare area SA and a second update is recorded in the track # 2.

As shown in fig. 1A, although only data a ″ obtained by updating original data a twice exists in the logical space, in cases 1 to 4, the last update (i.e., data a ") is recorded in a different location in the physical space.

Referring to fig. 1B, in case 5, original data (data a), a first update of data a (data a'), and a second update of data a (data a ") are sequentially recorded in a physical volume space of a track #2 on a user data area. Referring to fig. 1C, in case 6, original data (data a), a first update of data a (data a'), and original data (data B) are sequentially recorded in a physical volume space of a track #2 on a user data area.

Technical problem

As shown in case 5 and case 6, although the physical recording states in case 5 and case 6 are the same, the actual information recording medium differs in the recording states in case 5 and case 6. Therefore, the block to be recorded needs to include specific information so that the drive system can recognize two different situations.

Technical scheme

Aspects of the present invention provide an information recording medium, a recording/reproducing apparatus, and a recording/reproducing method by which replacement of Logical Overwrite (LOW) can occur in any area of a spare area and a user data area, thereby improving the efficiency of data reproduction.

Advantageous effects

The data recording/reproducing method and the replacement entry restoring method described above can also be embodied as computer readable codes on a computer readable recording medium. The computer readable recording medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, and carrier waves (such as data transmission through the internet). The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. In addition, functional programs, codes, and code segments for implementing the data recording/reproducing method and the replacement entry restoring method can be constructed by programmers in the field of information recording.

Drawings

Fig. 1A to 1C are reference diagrams illustrating a conventional problem;

fig. 2 is a block diagram of a recording/reproducing apparatus according to an embodiment of the present invention;

fig. 3 is a detailed block diagram of the recording/reproducing apparatus of fig. 2;

fig. 4 is a block diagram of a structure of an information recording medium used in the recording/reproducing apparatus of fig. 2;

FIG. 5 is a block diagram of a data structure of the replacement entry shown in FIG. 4;

FIG. 6 is a block diagram of a structure of a block that is a unit of distinguishing recording/reproducing in user data of the information recording medium shown in FIG. 4 from a user data area of the information recording medium shown in FIG. 4;

fig. 7A illustrates a physical volume space of an information recording medium on which original blocks and replacement blocks have been recorded according to an embodiment of the present invention;

FIG. 7B illustrates a logical volume space of the information recording medium illustrated in FIG. 7A;

FIG. 8 is a block diagram of a structure of a replacement entry generated based on the recorded blocks shown in FIG. 7A;

fig. 9A to 9D are block diagrams of the structure of a replacement entry restored based on the recorded blocks shown in fig. 7A;

fig. 10 is a flowchart illustrating a method of recording data according to an embodiment of the present invention;

fig. 11 is a flowchart illustrating a method of restoring a replacement entry according to the present invention.

Best mode for carrying out the invention

According to an aspect of the present invention, there is provided an information recording medium including: a user data area for recording user data; and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area, the recording block including at least one of an original address indicating a location of the original recording block or a previous address indicating a location of an immediately previous recording block.

The recording block may include a data part containing original data or replacement data and an additional information part containing additional information regarding the original data or the replacement data. The additional information part may contain at least one of the original address or the previous address.

According to another aspect of the present invention, there is provided an information recording medium including: a user data area for recording user data; and a spare area for replacing a defect in the user data area, wherein a replacement recorded block, which replaces an original recorded block recorded in the user data area, is recorded in the spare area or an unrecorded area of the user data area, and each of the original recorded block and the replacement recorded block includes identification information for determining whether each recorded block is the original recorded block or the replacement recorded block.

Each recording block may include a data part containing original data or replacement data and an additional information part containing additional information regarding the original data or the replacement data. The additional information part may contain identification information.

The additional information part may include at least one of an original address field indicating a location of an original recording block or a previous address field indicating a location of an immediately previous recording block. The identification information may be a specific identifier recorded in at least one of the original address field or the previous address field.

According to another aspect of the present invention, there is provided an information recording medium including: a user data area for recording user data; and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area, and a value of a physical address of the replacement recording block is always larger than a value of a physical address of a recording block preceding the replacement recording block and a value of a physical address of the original recording block or is always smaller than a value of a physical address of a recording block preceding the replacement recording block and a value of a physical address of the original recording block.

According to another aspect of the present invention, there is provided a recording/reproducing apparatus including: a writing/reading unit writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; and a controller which controls the write/read unit to write the recording block onto the information recording medium, wherein the written recording block contains at least one of original address information indicating a location of the original recording block or previous address information indicating a location of an immediately previous recording block of the original recording block.

According to another aspect of the present invention, there is provided a recording/reproducing apparatus including: a writing/reading unit writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; and a controller which controls the write/read unit to write the recording block onto the information recording medium, wherein the write recording block includes identification information for determining whether the write recording block is an original recording block or a replacement recording block.

According to another aspect of the present invention, there is provided a recording/reproducing apparatus including: a writing/reading unit writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; and a controller controlling the writing/reading unit to write the replacement recorded block on the information recording medium such that a value of a physical address of the replacement recorded block is always greater than or always less than a value of a physical address of a previous replacement recorded block and a value of a physical address of an original recorded block.

According to another aspect of the present invention, there is provided a recording/reproducing apparatus including: a writing/reading unit writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; and a controller restoring replacement information regarding the original recording block and the replacement recording block by referring to an original address field of the replacement recording block indicating a position of the original recording block and a previous address field of the replacement recording block indicating a position of an immediately previous recording block, the immediately previous recording block being replaced with the replacement recording block.

According to another aspect of the present invention, there is provided a recording/reproducing method including: writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; writing a recording block on the information recording medium, wherein the recording block contains at least one of an original address field indicating a location of the original recording block or a previous address field indicating a location of an immediately previous recording block.

According to another aspect of the present invention, there is provided a recording/reproducing method including: writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; recording blocks are written on the information recording medium, wherein the recording blocks contain identification information for determining whether the written recording blocks are original recording blocks or replacement recording blocks.

According to another aspect of the present invention, there is provided a recording/reproducing method including: writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; the replacement recording block is written onto the information recording medium such that a value of a physical address of the replacement recording block is always larger than a value of a physical address of a recording block preceding the replacement recording block and a value of a physical address of the original recording block or is always smaller than the value of the physical address of the recording block preceding the replacement recording block and the value of the physical address of the original recording block.

According to another aspect of the present invention, there is provided a recording/reproducing method including: writing data to and reading data from an information recording medium having a user data area for recording user data and a spare area for replacing a defect in the user data area, wherein a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area; the replacement information on the original recording block and the replacement recording block is restored by referring to an original address field of the replacement recording block indicating a location of the original recording block and a previous address field of the recording block indicating a location of an immediately previous recording block, which is replaced with the replacement recording block.

In the case where the immediately preceding recording block is also the original recording block, the original address field and the previous address field may have the same value.

Where a form of expression of "at least one of a or B" is used herein, such expression should be interpreted as a or B, or a and B.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.

Fig. 2 is a block diagram of a recording/reproducing apparatus 200 according to an embodiment of the present invention. Referring to fig. 2, the recording/reproducing apparatus 200 includes a writing/reading unit 220 and a controller 210. The write/read unit 220 writes data to the information recording medium 400 and reads the written data to reproduce the written data under the control of the controller 210. The controller 210 controls the write/read unit 220 to write/read data by a recording unit block or to obtain valid data by processing data read by the write/read unit 220. The recording/reproducing device 200 disclosed herein includes means for recording and reproducing; however, as will be appreciated by those skilled in the art, some aspects of the invention relate only to recording information and other aspects of the invention relate only to reproducing information. Thus, as the context implies, a recording/reproducing device includes a device for recording, a device for reproducing, or a device for recording and reproducing information.

In performing the write operation, the controller 210 controls the write/read unit 220 to write data by performing Logical Overwrite (LOW) according to a command of a host or under the control of the recording/reproducing device 200. LOW denotes a technique of updating data recorded in a user data area of a write-once recording medium by recording replacement data in a spare area or in an unrecorded area of the user data area, and managing addresses of original data and replacement data such that a host cannot recognize any change in logical addresses. Such management is achieved by writing a replacement entry and recording the replacement entry on the information recording medium. As described above, the controller 210 controls the write/read unit 220 to write replacement data to a spare area or to an unrecorded area of the user data area according to LOW. The controller 210 generates a block including a data part based on a host write command and an additional information part having a previous address field and an original address field of the block to be replaced, and controls the write/read unit 220 to write the generated block to the information recording medium 400. In case that a replacement entry having replacement information is not reproduced before recording or reproducing data, the controller 210 restores the replacement entry using values of a previous address field and an original address field included in the additional information part of the block.

Fig. 3 is a detailed block diagram of the recording/reproducing apparatus 200 in fig. 2. Referring to fig. 3, the recording/reproducing apparatus 200 (i.e., a disc drive) includes a pickup 250, which serves as the writing/reading unit 220. The information storage medium 400 is mounted to be accessed by the pickup 250. The recording/reproducing apparatus 200 includes a host interface (I/F)211, a Digital Signal Processor (DSP)212, an RF AMP213, a servo 214, and a system controller 215, and the host interface (I/F)211, the Digital Signal Processor (DSP)212, the RF AMP213, the servo 214, and the system controller 215 serve as the controller 210.

In the case where data is to be written to the information storage medium 400, the host I/F211 receives data and a write command to be written and information on a logical address of the data to be written from the host 240 and then transmits the received data, command and information to the system controller 215.

The system controller 215 receives a write command from the host I/F211 and performs initialization required for writing. Specifically, in a case other than the case where data is rewritten to the recorded area, the system controller 215 controls the pickup 250 to write the data to the address indicated by the write command. On the other hand, when data is rewritten to a recorded area, the system controller 215 controls the pickup 250 to write update data to an unrecorded area of the user data area using linear replacement, generates a defect entry indicating a state of replacement based on LOW, and writes the defect entry to the temporary defect information area of the information recording medium 400. Since data is written on the information recording medium 400 in recording unit blocks, the system controller 215 generates a block by determining values of the previous address field and the original address field with reference to a block that is not replaced and a replacement entry, and controls the pickup 250 to write the block into the information recording medium 400.

The DSP 212 adds additional data, such as parity, to the data to be written received from the host I/F211 to implement error correction, and performs ECC (error correction code) encoding on the resulting data to be written to generate an error-corrected block (i.e., an ECC block), which is then modulated in a predetermined scheme. The RF AMP213 converts data output from the DSP 212 into an RF signal. The pickup 215 receives the RF signal from the RF AMP213 and writes the RF signal into the information storage medium 400. The servo 214 receives a command required for servo control from the system controller 215 and servo-controls the pickup 250.

In the case where data is to be read from the information storage medium, the host I/F211 receives a read command from the host 240. The system controller 215 performs initialization required for reading. Specifically, the system controller 215 converts the logical address indicated by the read command into a physical address, and searches for a replacement address from the replacement entry based on the converted physical address. If the replacement entry cannot be read, the system controller 215 restores the replacement entry. The replacement entry is restored by referring to the original address information and the previous address information included in the recorded block. Hereinafter, the restoration of the replacement entry will be described in more detail.

The pickup 250 irradiates a laser beam onto the information storage medium 400, receives the laser beam reflected by the information storage medium 400, and then outputs an optical signal obtained from the received laser beam. The RF AMP213 converts an optical signal received from the pickup 250 into an RF signal and supplies modulated data extracted from the RF signal to the DSP 212 and a servo control signal extracted from the RF signal to the servo 214. The DSP 212 demodulates the modulated data, performs ECC on the demodulated data, and then outputs the resultant data.

The servo 214 receives a servo signal from the RF AMP213 and a command required for servo control from the system controller 215, and servo-controls the pickup 250. The host I/F211 transmits data output from the DSP 212 to the host 240.

Fig. 4 is a block diagram of the structure of an information recording medium 400 in the case where the information recording medium is a disc. Referring to fig. 4, the information recording medium 400 includes a lead-in area 410, a data area 420, and a lead-out area 430.

The lead-in area 410 includes a second disc management area 411, a Temporary Disc Management Area (TDMA)412, a first disc management area 413, the data area 420 includes a first spare area 421, a user data area 422, a second spare area 423, and the lead-out area 430 includes a third disc management area 431 and a fourth disc management area 432.

The TDMA 412 indicates an area for recording information for temporary defect management and temporary information recording medium management, which are required to manage the write-once information recording medium. The TDMA 412 includes a temporary defect list (TDFL)414 as temporary defect information, a Temporary Disc Definition Structure (TDDS)415 as temporary defect management information, and a Space Bit Map (SBM) 416.

The TDFL 414 indicates information on a defect and includes information on a location of defect data and information on a location of replacement data of the defect data. Specifically, the TDFL 414 includes a replacement entry 417.

Fig. 5 shows a data structure of the replacement entry 417. Referring to fig. 5, the replacement entry 417 includes an original address 418 and a replacement address 419. Original address 418 indicates the starting sector address of the original block and replacement address 419 indicates the starting sector address of the replacement block. Since replacement is performed in units of blocks, which are units of recording/reproducing data, the state of replacement is represented as a block.

Referring again to fig. 4, the TDDS 415 stores temporary defect information 414, a location pointer of the SBM 416 and a drive area (not shown), information on a location and size of a spare area allocated at initialization, write protection information, information on a location and size of a temporary defect management area (not shown) allocated in the data area 420, information on the user data area 422, information on locations of the first and second spare areas 421 and 423 in which replacement data can be written, and information on an address of last data written in the user data area 422, and the like.

The SBM 416 represents a mapping in which recorded clusters and unrecorded clusters of the user data area 422 are represented as different bit values. The SBM 416 is used when the user data area 422 is used in the random recording mode. On the other hand, when the user data area 422 is used in the continuous recording mode, recording management information in which the state of the information recording medium on which data is recorded is represented as entry information is used instead of the SBM 416.

When the write-once information recording medium is completed, the first, second, third, and fourth disc management areas 413, 411, 431, and 432 are allocated to record the last temporary management information.

The data area 420 includes a first spare area 421, a user data area 422, and a second spare area 423, which are sequentially arranged. The first spare area 421 and the second spare area 423 are allocated to record replacement data, i.e., data replacing data recorded in the user data area 422. The first spare area 421 and the second spare area 423 may store replacement data for replacing defect data or replacement data required for LOW, i.e., replacement data for replacing user data.

The user data area 422 indicates an area where user data is recorded. Specifically, replacement data replacing user data according to LOW is recorded not only in the first spare area 421 or the second spare area 423 but also in the user data area 422. The blocks recorded as a unit are written in the user data area 422.

Fig. 6 illustrates a recording unit block 500 according to an embodiment of the present invention. Referring to fig. 6, a recording unit block 500 includes a data part 510 and an additional information part 520. Data portion 510 is user data. If the recording unit block 500 is an original block, the data part 510 is original data originally recorded. If the recording unit block 500 is a replacement block, the data part 510 is replacement data.

The additional information part 520 includes additional information about the original data or the replacement data. As shown in fig. 6, the additional information part 520 includes a previous address field 521 and an original address field 522. The original address field 522 records an address representing the location of the original block. The previous address field 521 records an address indicating the position of an immediately preceding block, which is replaced by the recording unit block 500. The additional information part 520 may have an error correction structure different from that of the data part 510.

Fig. 7A shows the structure of an information recording medium on which blocks have been recorded, wherein the blocks are units of recording/reproduction. More specifically, fig. 7A shows a state of an information recording medium on which address information is stored in a previous address field and an original address field of a block if the block is composed of one sector. In a general optical system, a host manages data in units of sectors (2048 bytes), and a drive system manages data in units of 16 sectors or 32 sectors on an information recording medium.

Referring to fig. 7A, when the host commands the drive system to write data a to a logical sequence number "a" (lsna) to record the data a, the drive system writes the data a to a physical sequence number "a" (psna) on the information recording medium, wherein the psna corresponds to the lsna. At this time, the values of the previous address field and the original address field included in the block are both set to "0" to indicate that the block is an original block. The original block is the block that was originally recorded and cannot replace any block. In this way, the original block can be distinguished from the replacement block.

Other methods may be used to distinguish the original block from the replacement block. For example, the value of the previous address field or the value of the original address field may be set to a specific identifier. In addition, the value of the previous address field and the value of the original address field may be set to the same value to indicate that the block includes original data. In the case where original data is recorded, the same value may be a value representing the PSN.

A method of recording the replacement block will now be described. In order to perform a first update of data A with data A ' by LOW, the host commands the drive system to write data A ' to LSN a, and the drive system writes data A ' to an unrecorded area PSN a-1 on the information recording medium by determining that PSN a corresponding to LSN a on the information recording medium has been recorded with data. As shown in fig. 8, the drive system generates a replacement entry #1 indicating that PSN a has been replaced with PSN a-1. Fig. 8 shows a replacement entry #1 in which PSN a is set as the original address and PSN a-1 is set as the replacement address. Referring again to fig. 7A, the values of the previous address field 701 and the original address field 703 in the replacement block having the data a 'and recorded in PSN a-1 are both set to PSN a to indicate that the replacement block recorded in PSN a-1 replaces the block recorded in PSN a and that the physical address (i.e., the original address) corresponding to the logical address of the data a' recorded in PSN a-1 is PSN a.

Thereafter, in order to perform a second update on the data a according to the LOW with data a ", i.e., update the data a', the host instructs the drive system to write the data a" to the lsna, the drive system writes the data a "to the unrecorded area PSN a +1 on the information recording medium by determining that the PSN a corresponding to the lsna has been recorded with data on the information recording medium, and determining from the replacement entry #1 that the PSN a has been replaced with PSN a-1. In addition, the drive system changes the replacement entry #1 to indicate that PSN a has been replaced with PSN a +1, as shown in fig. 8. Referring again to FIG. 7A, the value of the previous address field 701 in the replacement block having data A' and recorded at PSN a +1 is set to PSN a-1 to indicate that the replacement block replaces the block recorded at PSN a-1. The value of the original address field 703 in the replacement block having data a ″ and recorded in PSN a +1 is set to PSN a to indicate that the physical address (i.e., the original address) corresponding to the logical address of data a ″ recorded in PSN a +1 is PSN a.

After the second update of the data a with the data a ″, in a case where the data B is to be written to the information recording medium, the host commands the drive system to write the data B to the LSN a +1, and the drive system writes the data B to the unrecorded area PSN a +2 on the information recording medium by determining that the PSN a +1 corresponding to the LSN a +1 has been recorded with the data (i.e., the data a). In addition, the drive system generates a replacement entry #2 to indicate that PSN a +1 has been replaced with PSN a +2, and thus LSN a +1 corresponds to PSN a +2, as shown in fig. 8. Referring again to fig. 7A, the values of the previous address field 701 and the original address field 703 in the block including data B and recorded at PSN a +2 are both set to PSN a +1 to indicate that the block recorded at PSN a +2 includes original data, i.e., data B, (although sequentially recorded), and that the physical address (i.e., the original address) corresponding to the logical address of data B recorded at PSN a +2 is PSN a + 1.

Thereafter, in order to update data B with data B ' according to LOW, the host commands the drive system to write data B ' to LSN a +1, and the drive system writes data B ' to an unrecorded area PSN a +3 on the information recording medium by determining that PSNa +1 corresponding to LSN a +1 has been recorded with data (i.e., data a ") and determining from the replacement entry #2 that the original address PSNa +1 has been replaced with PSNa + 2. In addition, the drive system changes the replacement entry #2 to indicate that PSN a +1 has been replaced with PSN a + 3. Fig. 8 also shows a changed replacement entry #2, in which the replacement address is PSN a + 3. Referring again to fig. 7A, the value of the previous address field 701 in the replacement block having data B' and recorded at PSN a +3 is set to PSN a +2 to indicate that the replacement block replaces the block recorded at PSN a + 2. The value of the original address field 703 in the replacement block having the data B 'and recorded at the PSN a +3 is set to the PSN a +1 to indicate that the physical address (i.e., the original address) corresponding to the logical address of the data B' recorded at the PSN a +3 is the PSN a + 1. Fig. 7B shows the resulting logical volume space 705 produced by replacing data a with data a ' and then data a "and then data B ' with data B ' and then data B is sequentially recorded. That is, data A "corresponds to LSN a and data B' corresponds to LSN a + 1.

A method of restoring the replacement entry will now be described. If the information recording medium having data written thereon as described above is loaded into the drive system and the drive system cannot obtain the last TDFL from the temporary defect management area of the lead-in area or the lead-out area of the information recording medium, the drive system must recover at least a replacement entry in the TDFL, which indicates the state of the information recording medium having replacement data required when a defect or LOW is generated recorded thereon. The replacement entry is restored using values of the previous address field and the original address field included in the additional information part of the block recorded on the information recording medium. The replacement entry recovery will now be described with reference to fig. 7A to 9D.

First, assuming values shown in fig. 7A, for example, the drive system reads a block recorded at PSN a-1, and determines from the value PSN a set in the previous address field 701 of the read block that PSN a-1 previously replaced PSN a and determines from the value PSN a set in the original address field 703 of the read block that data a' recorded at PSN a-1 has a logical address corresponding to PSN a. According to this determination, the drive system restores the replacement entry #1 in fig. 9A, the replacement entry #1 representing the state of the information recording medium on which the block recorded at PSN a has been replaced with the block recorded at PSN a-1.

Then, the drive system reads the block recorded at PSN a, and determines from the values "0" set in the previous address field 701 and the original address field 703 of the read block that the read block PSN a is an original block, i.e., a block that is not replaced.

Thereafter, the drive system reads the block recorded at PSN a +1, and determines from the value PSN a-1 set in the previous address field 701 of the read block PSN a +1 that the read block PSN a +1 has replaced the block recorded at PSN a-1 and determines from the value PSN a set in the original address field 703 of the read block PSN a +1 that the user data contained in the read block PSN a +1 has a logical address corresponding to PSN a. Since the drive system can determine from the replacement entry #1 in fig. 9A that the block having the address PSN a has been replaced with the block having the address PSN a-1 and that the block having the address PSN a-1 has been replaced with the block having the address PSN a +1, the drive system changes the replacement address of the replacement entry #1 in fig. 9A from PSNa-1 to PSN a +1 to restore the replacement entry #1 in fig. 9B.

Then, the drive system reads the block recorded at PSN a +2, and determines from the value PSN a +1 set in the previous address field 701 of the read block that the read block PSN a +2 has replaced the block having the address PSN a +1, and determines from the value PSN a +1 set in the original address field 703 of the read block PSN a +2 that the user data included in the read block PSN a +2 has a logical address corresponding to PSN a + 1. According to this determination, the drive system restores the replacement entry #2 in fig. 9C, the replacement entry #2 representing the state of the information recording medium on which PSN a +1 has been replaced with PSN a + 2.

Thereafter, the drive system reads the block recorded at PSN a +3, and determines from the value PSN a +2 set in the previous address field 701 of the read block that the read block PSN a +3 has replaced the block recorded at PSN a +2 and determines from the value PSN a +1 set in the original address field 703 of the read block that the user data included in the read block PSN a +3 has a logical address corresponding to PSN a + 1. Since the drive system can determine from the replacement entry #2 in fig. 9C that the block having the address PSN a +1 has been replaced with the block having the address PSN a +2, and can determine from the value PSN a +2 read from the block PSN a +3 that the block having the address PSN a +2 has been replaced with the block having the address PSN a +3, the drive system changes the replacement address of the replacement entry #2 in fig. 9C from PSN a +2 to PSN a +3 to restore the replacement entry #2 in fig. 9D.

As described above, the exact replacement entry #1 and the exact replacement entry #2 are recoverable using the previous address field and the original address field included in the additional information part of the block. More specifically, in the method of replacement entry recovery according to an embodiment of the present invention, the location of the last replacement block is identifiable from a value set in a previous address field of a reproduced block having an original address field storing the identified value, so that a correct replacement entry for the block is recoverable. In other words, the original address field of the reproduced block provides a physical address of the original block, which is to be set as an original address of a replacement entry of the reproduced block, and the previous address field of the reproduced block provides a physical address of a last replacement block of the original block, which is to be set as a replacement address of the replacement entry.

In the example shown in fig. 7A, it can be seen that if a recorded block includes only the original address field 703, a replacement entry of the recorded block cannot be correctly restored. However, by limiting the method of recording the replacement block, the replacement entry can be correctly restored using only the original address field 703 of the reproduced block. In the case where replacement blocks are recorded in order, replacement entries can be restored using only the values recorded in the original address field 703 by referring to the values of the original address field 703 and a predetermined order. That is, in the case where the PSN sequentially later has a value corresponding to the PSN of the block sequentially earlier recorded in the original address field 703, it may be determined that the block sequentially later replaces the block sequentially earlier. Therefore, the PSN of the sequentially last block having the value corresponding to the PSN of the sequentially earlier block recorded in the original address field 703 is the last replacement block of the sequentially earlier block.

For example, if replacement is performed under the rule that the physical address of the current replacement block is always larger than the physical addresses of the respective previous replacement blocks and the physical address of the original block, it may be determined from the replacement history contained in the arrangement of the physical addresses that the replacement block having the highest physical address in order among the replacement blocks is the last replacement block.

As another example, if replacement is performed under a rule that the physical address of the current replacement block is always smaller than the physical addresses of the respective previous replacement blocks and the physical address of the original block, it may be determined from the replacement history contained in the arrangement of the physical addresses that the replacement block having the lowest physical address in order among the replacement blocks is the last replacement block.

If only the previous address field 701 is contained in the block in the case of fig. 7A, an erroneous replacement entry is recovered by recognizing that the block recorded at the PSN has been replaced with the block recorded at PSN a + 3. However, if data B is allowed to be recorded in LSN a +2 instead of LSN a +1 (i.e., if writing of data into an area in which data is recorded in physical space although it is not recorded in logical space is prohibited or if the drive system notifies the host of an error when a command to write data into the above-mentioned area is received), data B may be recorded in PSN a +2 corresponding to LSN a +2, and data B' may be recorded in PSN a +3 according to LO W. As described above, the problems shown in fig. 1B and 1C can be solved if writing of data to an area where data is recorded in a physical space although it is not recorded in a logical space is prohibited or if the drive system notifies the host of an error when a command to write data to the above-mentioned area is received. Only in this case, even in the case where the replacement entry is restored using only the previous address field as the address information, the replacement entry can be correctly restored.

Fig. 10 is a flowchart illustrating a method of recording data according to an embodiment of the present invention. In operation 1001, a drive system receives a data write command from a host. Since the host operates using only the logical address, the host supplies the drive system with the logical address of the data to be recorded.

In operation 1002, the drive system translates the logical address indicated by the data write command into a physical address. In operation 1003, the drive system determines whether the physical address is unrecorded. In the case where the physical address is not recorded, the drive system determines that the data indicated by the data write command is not replacement data but new user data, and thus, both the previous address field and the original address field are set to 0 in operation 1004.

When it is determined that the physical address is recorded, the drive system determines that the data indicated by the data write command represents replacement data with which to update the data already recorded at the recorded physical address, and thus, in operation 1005, searches for a replacement entry of the original data.

In the case where a replacement entry is not found, the values of the previous address field and the original address field of the replacement data (i.e., the replacement block to be currently recorded) are each set to a physical address corresponding to the logical address indicated by the data write command in operation 1006. The physical address indicates a location where original user data has been recorded. In operation 1007, a replacement entry including the original address and the replacement address is generated. The original address identifies the physical address of the original user data and the replacement address identifies the physical address at which the current replacement block is to be recorded.

In the case where a replacement entry is found, it may be determined whether the original data has been previously replaced, and thus, the values of the previous address field and the original address field of the current replacement block are determined with reference to the found replacement entry. In other words, at operation 1008, the previous address field of the current replacement block is set to the replacement address of the found replacement entry, and the original address field of the current replacement block is set to the original address of the found replacement entry. In operation 1009, the replacement address of the found replacement entry is changed from the physical address of the previous replacement block to the physical address of the current replacement block.

In operation 1010, a current replacement block is generated by including data indicated by a data write command of the host and additional information (a previous address field and an original address field), and the current replacement block is recorded at a replacement address on the information recording medium. A newly generated replacement entry or a changed replacement entry is recorded in a lead-in area or a lead-out area of the information recording medium in operation 1011.

FIG. 11 is a flow diagram illustrating a method of restoring a replacement entry in accordance with an aspect of the subject invention. First, in operation 1110, a block recorded in a user data area is reproduced, and information contained in a previous address field and an original address field is obtained from an additional information part of the reproduced block.

At operation 1120, a replacement entry including the replacement address and the original address is restored. The physical address of the first reproduction block is set to the replacement address of the replacement entry, and the value of the original address field included in the additional information part of the first reproduction block is set to the original address of the replacement entry.

In operation 1130, a second block, which is adjacent to the first reproduction block and recorded in the user data area, is reproduced, and information contained in the previous address field and the original address field is obtained from the additional information part of the second block. In operation 1140, it is determined whether the original address of the restored replacement entry coincides with the information contained in the original address field of the second reproduction block.

The second reproduction block is new user data different from the user data of the first reproduction block if the original address of the restored replacement entry is different from the information contained in the original address field of the second reproduction block. Accordingly, the method returns to operation 1120 to restore the replacement entry of the second block reproduced in operation 1130.

If the original address of the restored replacement entry is the same as the information contained in the original address field of the second reproduction block, the second block reproduced in operation 1130 is not new user data but replacement data replacing the same user data as the user data replaced by the first reproduction block. Accordingly, in operation 1150, the replacement address of the restored replacement entry is changed to the physical address of the next reproduction block.

Then, in operation 1160, it is determined whether there is a block to be additionally reproduced. If there is a block to be additionally reproduced, the method returns to operation 1110 to reproduce the remaining blocks. If there are no blocks to be additionally reproduced, the method ends.

According to the method of the present invention as described above, replacement information can be efficiently recovered in a system in which LOW replacement occurs in a spare area or a user data area. Accordingly, the efficiency of data reproduction is improved. Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.

Claims (6)

1. A method of allocating an area, comprising:

allocating a user data area for recording user data;

allocating a spare area for replacing a defect detected in the user data area,

wherein:

a replacement recording block replacing an original recording block recorded in the user data area is recorded in the spare area or an unrecorded area of the user data area;

each of the original recording block and the replacement recording block includes identification information for determining whether the respective recording block is the original recording block or the replacement recording block.

2. The method of claim 1, wherein:

each recording block includes a data part containing original data or replacement data and an additional information part containing additional information about the original data or the replacement data;

the additional information part contains identification information.

3. A recording/reproducing method comprising:

writing data to and/or reading data from an information recording medium by a writing/reading unit, the information recording medium including a user data area for recording user data and a spare area;

writing, by the controller, a replacement block for replacing an original block recorded on the information recording medium and a defect list entry including location information of the original block and location information of the replacement block to the information recording medium,

wherein the original block and the replacement block respectively contain information for identifying whether the corresponding block is a replacement block, and the replacement data stored in the replacement block is reproduced using the defect list entry.

4. A recording method, comprising:

recording blocks including user data and identification information are written on the information recording medium, wherein the identification information identifies whether the recording blocks are original recording blocks or replacement recording blocks.

5. The method of claim 4, wherein:

the write recording block includes a data part and an additional information part, the data part including original data or replacement data, the additional information part including additional information about the original data or the replacement data;

the additional information part contains identification information.

6. The method of claim 5, wherein:

the additional information part contains at least one of an original address field indicating a location of an original recording block or a previous address field indicating a location of an immediately previous recording block;

the identification information is a specific identifier recorded in at least one of the original address field or the previous address field.