JP2007193883A - Data recording device and method, data reproducing device and method, and data recording and reproducing device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently perform garbage collection in a data recording device and a method, a data reproducing device and a method, and a data recording and reproducing device and a method. <P>SOLUTION: The recording and reproducing device is provided with a recording medium 20 having the prescribed capacity, a nonvolatile solid memory 28 constituting storage space with the recording medium 20 and having the prescribed capacity, a control part 26 controlling access for the recording medium 20, a buffer memory 27 having the prescribed capacity, and a memory control part 30 controlling access to the nonvolatile solid memory 28. The memory control part 30 determines whether the garbage collection is required or not in accordance with the access from a host device 1, and the garbage collection is performed in parallel with reading or writing of data. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a data recording apparatus and method, a data reproducing apparatus and method, and a data recording / reproducing apparatus, which are provided with a recording medium and a nonvolatile storage medium, and in which data is written and read based on a common file system, and Regarding the method.

  There are various types of nonvolatile solid-state memories, but NAND flash memories are used in mass storage devices that have attracted attention in recent years. The nonvolatile solid-state memory erases data written in an arbitrary area when data is already written in the arbitrary area and new data is written in the arbitrary area (also called a program). There is a need. This erasing operation takes about ms units. A unit to be erased is called a block and is larger than a unit (page) for accessing data.

  For example, in the nonvolatile solid-state memory of Toshiba 1 Gbit NAND EEPROM TC58NVG0S3AFT05, the block size is 128 KB (excluding ECC), and the page size is 2 KB (excluding ECC). The time required for erasing data written in one block is about 2 ms (typical). The maximum time required for erasing is about 4 ms.

  In this manner, since a predetermined time is required for the “data erasing” operation before the “data writing” operation, the host device is kept waiting for that time.

  Therefore, generally, a so-called write-once type data writing process is performed, in which the changed data is written to another location where erasing has already been performed (that is, data can be written immediately). Then, the table for converting the logical address placed in the storage device into the physical address is changed, and the physical address and the logical address of the added block are made to correspond to each other. At the same time, a process for invalidating the page in the block containing the data is performed. Since invalid pages cannot be used for writing new data, the entire block is moved after valid data is moved to another block when the storage device is not accessed (for example, idle time). Is erased, so-called garbage collection is performed to prepare for future writing of new data. Also, when an arbitrary file is deleted and an invalid page is generated in the block, garbage collection is performed in the same manner as described above.

JP-A-9-97218 JP-A-11-126488

By the way, since there is a limit on the number of times data can be rewritten in the nonvolatile solid-state memory (10 ⁴ to 10 ⁵ ), it is necessary to make the number of times data is written in each block the same. The process performed for this purpose is called Wear Leveling (average of the number of rewrites).

  Here, various methods for realizing the processing by Wear Leveling while adopting the write-once type rewriting processing have been proposed (for example, cited references 1 and 2).

  Cited Document 1 discloses a method for realizing the averaging of the number of data writes by selecting a block having a small number of erases from among blocks requiring garbage collection and executing the garbage collection.

  In the cited document 2, the memory is divided into an area for data rewriting and an area for executing garbage collection, whereby the number of times of writing is averaged without directly using the number of times of erasure. It is shown.

  However, in any of the methods, garbage collection is not executed because the host device is not allowed to wait while there is an access from the host device. For this reason, if there are a large number of invalid pages (pages on which data cannot be written) even though the nonvolatile solid-state memory has a sufficient storage capacity, there will be insufficient blocks to be written during data writing. Sometimes. In such a case, it is necessary to erase the file or execute garbage collection to create an area (block) where data can be written. As a result, the transfer rate of data supplied from the host device Will drop significantly.

  Therefore, in the present invention, in view of such a problem, even if the data is being accessed from the host device, the garbage collection is performed and the host device can execute the garbage collection by taking advantage of the characteristic that the data arrangement information can be managed by itself. An object of the present invention is to provide a data recording apparatus and method, a data reproducing apparatus and method, and a data recording / reproducing apparatus and method capable of keeping the transfer rate of supplied data constant.

  In order to solve the above-described problem, the data recording apparatus according to the present invention is connected to the host apparatus, and the data is accessed by the first data access mode in which data is accessed according to the control of the host apparatus. In a data recording apparatus having a second data access mode for performing access to data, the data recording apparatus has a first data area to which a first physical address is assigned, and when writing data to the first data area, A nonvolatile solid-state memory that requires an erasing operation of the area to be written and a second data area to which a second physical address is attached, and when writing data to the second data area, The storage medium that does not need to erase the area to be written, the connection means to which the host device is connected, and the data transferred from the host device are stored in the nonvolatile solid-state memory. Write means for writing to any area of the storage medium or any area of the storage medium, and when the second data access mode is selected and data is transferred from the host device connected to the connection means, or writing When data is written to the nonvolatile solid-state memory or recording medium by means, a judgment means for determining whether garbage collection is necessary for the nonvolatile solid-state memory, and executing garbage collection for the nonvolatile solid-state memory Non-volatile that controls the writing means so that the data transferred from the host device is written to a predetermined area of the storage medium when the garbage collection is executed and the judging means determines that the garbage collection is necessary. Control garbage collection execution means to perform garbage collection on solid-state memory And a that control means.

  In order to solve the above-described problem, the data recording method according to the present invention includes a first data access mode in which a host device is connected and data is accessed according to the control of the host device, and its own control. In the data recording method of the data recording apparatus having the second data access mode for accessing data by the first data access mode, when the second data access mode is selected and data is transferred from the host apparatus, Write data to a nonvolatile solid-state memory that has a first data area with a physical address and that needs to be erased when writing data to the first data area. The determination process for determining whether garbage collection is necessary for the nonvolatile solid-state memory, and the determination process If it is determined that storage collection is necessary, the data transferred from the host device has the second data area to which the second physical address is assigned, and the data is stored in the second data area. When writing, garbage is written to the nonvolatile solid-state memory in parallel with the writing process of writing to a predetermined area of the recording medium that does not require the erasing operation of the area to be written and the data writing operation by the writing process. A garbage collection execution step for executing collection is provided.

  Further, in order to solve the above-described problem, the data reproducing apparatus according to the present invention is connected to the host device, and the first data access mode in which access to data is performed according to the control of the host device, and its own control. In a data reproducing apparatus having a second data access mode for accessing data by using the first data area having the first physical address and writing data in the first data area A nonvolatile solid-state memory that requires an erasing operation of the area to be written, and a second data area to which a second physical address is attached, and when writing data to the second area, A storage medium that does not require an erasing operation of the area to be written, a buffering memory used for buffering data, and a connection to which a host device is connected. And a reading means for reading data from an arbitrary area of the nonvolatile solid-state memory or an arbitrary area of the storage medium in accordance with an instruction of the host device and a second data access mode are selected and connected to the connecting means Judgment means for judging whether garbage collection is necessary for the nonvolatile solid-state memory and a garbage collection execution means for executing garbage collection for the nonvolatile solid-state memory when an instruction to read data is issued from the host device When the determination means determines that garbage collection is necessary, the reading means is controlled to read the necessary data from the nonvolatile solid-state memory onto the buffering memory, and the garbage solid-state memory is garbage collected. Control garbage collection means to execute collection. And control means for.

  In addition, in order to solve the above-described problems, the data reproduction method according to the present invention includes a first data access mode in which a host device is connected and data is accessed according to the control of the host device, and its own control. In the data reproducing method of the data reproducing apparatus having the second data access mode for accessing the data by the first data access mode, when the second data access mode is selected and the host device instructs to read the data, A non-volatile solid-state memory that has a first data area to which a physical address is assigned, and that requires an erasing operation of the area to be written when data is written to the first data area. A decision process that determines whether collection is necessary, and if the decision process determines that garbage collection is necessary A read process for reading data required from the nonvolatile solid-state memory onto the buffering memory, and a garbage collection execution process for executing garbage collection on the nonvolatile solid-state memory in parallel with the data read operation by the read process .

  In order to solve the above-described problem, the data recording / reproducing apparatus according to the present invention includes a first data access mode in which a host device is connected and data is accessed according to the control of the host device, A data recording / reproducing apparatus having a second data access mode for accessing data by control has a first data area to which a first physical address is assigned, and data is stored in the first data area. When writing, it has a nonvolatile solid-state memory that requires an erasing operation of the area to be written, and a second data area to which a second physical address is attached, and writes data to the second data area A storage medium that does not require an erasing operation of an area to be written, a buffering memory used for buffering data, and a host device In accordance with a command from the host device, a connection unit to be connected, a writing unit for writing data transferred from the host device to an arbitrary area of the nonvolatile solid-state memory or an arbitrary area of the storage medium, Reading means for reading data from an arbitrary area or an arbitrary area of a storage medium, and when the second data access mode is selected and data is transferred from a host device connected to the connecting means, or writing means When data is written to the non-volatile solid-state memory or the recording medium, the first determination means for determining whether garbage collection is necessary for the non-volatile solid-state memory and the second data access mode are selected. When reading data is instructed from the host device connected to the connection means, for the non-volatile solid-state memory, The second determination means for determining whether or not the garbage collection is necessary, the garbage collection execution means for executing the garbage collection for the nonvolatile solid-state memory, and the first determination means have determined that the garbage collection is necessary. In this case, the writing unit is controlled to write the data transferred from the host device to a predetermined area of the storage medium, and the garbage collection executing unit is controlled to execute the garbage collection for the nonvolatile solid-state memory. When the first control means and the second determination means determine that the garbage collection is necessary, the reading means is controlled so as to read the necessary data from the nonvolatile solid-state memory onto the buffering memory. Garbage collection to perform garbage collection on volatile solid-state memory And second control means for controlling the action execution means.

  In order to solve the above-described problem, the data recording / reproducing method according to the present invention includes a first data access mode in which a host device is connected and data is accessed according to control of the host device, In a data recording / reproducing method of a data recording / reproducing apparatus having a second data access mode for accessing data by control, when the second data access mode is selected and data is transferred from the host apparatus, or Data is stored in a non-volatile solid-state memory having a first data area to which a first physical address is assigned and which requires an erasing operation of the area to be written when data is written in the first data area. A first determination step of determining whether garbage collection is necessary for the nonvolatile solid-state memory when If it is determined in the first determination step that garbage collection is necessary, the data transferred from the host device has a second data area to which a second physical address is attached, When writing data to the data area, a non-volatile solid in parallel with the writing process of writing to a predetermined area of the recording medium that does not require the erasing operation of the area to be written, and the data writing operation by the writing process When a first garbage collection execution step for executing garbage collection on a memory and a second data access mode are selected and a data read command is instructed from the host device, garbage is collected from the nonvolatile solid-state memory. A second determination step for determining whether collection is necessary, and a determination that garbage collection is necessary by the second determination step In such a case, the read process for reading the necessary data from the nonvolatile solid-state memory onto the buffering memory and the garbage collection for the nonvolatile solid-state memory are performed in parallel with the data read operation by the read process. 2 garbage collection execution steps.

  In the present invention, garbage collection, which cannot be avoided when using a nonvolatile solid-state memory, is executed in parallel in a predetermined mode without interrupting data writing to another nonvolatile solid-state memory or recording medium. Or can be executed in parallel without affecting the data transfer to the host device.

  The present invention includes a nonvolatile solid-state memory that requires an erasing operation on an area to which data is to be written and another recording medium when data has already been written to the area. The data recording / reproducing apparatus has a function of controlling address information necessary for accessing the nonvolatile solid-state memory and other recording media, and efficiently executes garbage collection to eliminate fragmentation of the nonvolatile solid-state memory. The present invention relates to a data recording / reproducing apparatus.

  In the following embodiments, an HDD (Hard Disk Drive) is used as another recording medium, and a combination of an HDD and a nonvolatile solid-state memory is referred to as a hybrid storage device. In addition, the nonvolatile solid-state memory is assumed to be a NAND flash memory that requires an erasing operation on a block including the page when data is written to an area (page) where data has already been written. Yes. Also, the file system will be described as using an MS-DOS compatible FAT file system, but any system can be used as long as it is a system that manages data as a file, not limited to the MS-DOS compatible FAT file system. Can do.

<Configuration of data recording / reproducing apparatus>
FIG. 1 shows that a host device 1 such as a PC or AV device and a data recording / reproducing device 2 are integrated into IDE (Integrated Drive Electronics), SCSI (Small Computer System Interface), FC (Fibre Channel), and USB (Universal Serial Bus). It is a figure which shows a state when it is comprised and connected via the interface cables 3, such as.

  As shown in FIG. 1, the data recording / reproducing apparatus 2 writes data to the recording medium 20 and reads the written data, and a head drive that drives the head section 21 when accessing the recording medium 20. Connected to the head unit 21, a recording medium driving unit 23 that drives the recording medium 20 in a predetermined direction at a predetermined number of revolutions, a servo control unit 24 that controls the head driving unit 22 and the recording medium driving unit 23, and the head unit 21. The read / write channel unit 25 that performs predetermined processing on the supplied data, the control unit 26 that controls the servo control unit 24 and the read / write channel unit 25, and data are temporarily buffered. A buffer memory 27; a nonvolatile solid-state memory 28 having a predetermined capacity; a page buffer 29 having a predetermined capacity; A memory control unit 30 that controls the buffer memory 29, the nonvolatile solid-state memory 28, and the page buffer 29 when accessing the nonvolatile solid-state memory 28 to perform data retrieval; An arithmetic processing unit (CPU) 31 that operates by setting necessary commands and parameters in each unit, a memory 32 used for arithmetic operations by the CPU 31, and an interface control unit 33 that transmits and receives data, control information, and the like with the host device 1. With. In addition, the data recording / reproducing apparatus 2 has a first data access mode (PC mode) in which data is accessed according to the control of the host apparatus 1 and a second data access that is controlled by the data recording / reproducing apparatus 2 itself. Data access mode (AV mode).

<About the file system>
Here, a file system employed in the data recording / reproducing apparatus 2 according to the present invention will be described with reference to FIG. Hereinafter, the recording medium 20 is referred to as an HDD.

  The minimum unit for recording data in the HDD is a sector (usually 512 bytes). The host device 1 accesses the HDD using a logical block address (LBA). As described above, the minimum unit of the nonvolatile solid-state memory 28 is a page, and the size of this page does not necessarily match the size of the sector, but is composed of an integral multiple of the sector. Therefore, it is possible to easily relate the logical page number and the logical address. Therefore, the host device 1 can access the data recording / reproducing device 2 using the logical block address (LBA) to the nonvolatile solid-state memory 28 as well as the HDD.

  In a file system for managing files, a plurality of sectors (N) are set as one cluster, and this cluster is set as a minimum unit for reading and writing data. The FAT (File Allocation Table) is a table that records how one file is stored in the cluster. A file system managed using the FAT is called a FAT file system. Hereinafter, the cluster address is assumed to be obtained by simply dividing LBA by N, and in the description of this embodiment, N = 16 (1 cluster = 8 KByte).

  The FAT file system volume is composed of three areas (reserved area A, FAT area B, file and directory data area C). In the present embodiment, since only one partition is assumed, the volume and the partition are the same.

  In FIG. 2, the file name and its start cluster number are stored in the directory item D. The host device 1 reads the contents of the directory item D, knows the start cluster number ("12340h" in FIG. 2), and refers to the FAT entry (FAT Entry) corresponding thereto, and the next cluster of the file is the cluster number. Know that it is at "12341h". The host device 1 sequentially obtains the subsequent cluster number, and finally reads the arrangement information until the content of “1237Fh” is “EOF (End of File)”. Then, the host device 1 accesses the file based on the read arrangement information. Such an access method is called a PC mode.

  The recording medium 20 is managed by the above-described FAT (File Allocation Table) file system, and includes a user data area to which addresses (hereinafter referred to as physical addresses) are assigned at least for each predetermined data size (cluster). It is composed of a disk-shaped recording medium such as an HD (hard disk). The data recording / reproducing apparatus 2 may be configured using a non-volatile memory having a predetermined capacity instead of the recording medium 20. However, unlike the nonvolatile solid-state memory 28, the nonvolatile memory is a memory that does not require an erasing operation of data written in a target area (page) when data is written. For example, MRAM, FeRAM , NVSRAM, etc.

  When the recording medium 20 is a magnetic recording medium such as an HD, the head unit 21 uses a so-called magnetoresistive effect in which a resistance value changes depending on the magnitude and direction of an external magnetic field, and generates a signal magnetic field from the recording medium 20. It is constituted by a magnetic head having a magnetosensitive element for detection.

  The head drive unit 22 controls the operation of the head unit 21 in accordance with the control of the servo control unit 24.

  The recording medium control unit 23 controls the recording medium 20 to rotate at a predetermined rotational speed in accordance with the control of the servo control unit 24.

  The servo control unit 24 controls the recording medium driving unit 23 to rotate the recording medium 20 in a predetermined direction at a predetermined speed, and drives the head unit 21 to access a predetermined location on the recording medium 20. To control.

  The read / write channel unit 25 encodes (modulates) the supplied data and converts it into a digital bit sequence suitable for the characteristics of the recording / reproducing system, and then converts the converted data to the head unit 21. Supply. Further, the read / write channel unit 25 removes high frequency noise from the reproduction signal supplied from the head unit 21 at the time of data read operation, and then digitizes the data by an analog-to-digital converter (ADC). Demodulation is performed after predetermined processing is performed using a decoding method or the like.

  The control unit 26 manages data exchange among the buffer memory 27, the nonvolatile solid-state memory 28, the read / write channel unit 25, and the interface control unit 33, and performs processing related to the data format. In addition, when performing the processing, the control unit 26 also performs encoding using an error correction code and processing related to error detection and error correction.

  Data written from the host device 1 is stored in the recording medium 20 or the nonvolatile solid-state memory 28. The buffer memory 27 temporarily stores data (buffering) at that time or when reading data, and is used to suppress a decrease in performance due to a difference in transfer speed or a delay due to activation. In general, the buffer memory 27 is composed of DRAM or SRAM in consideration of cost.

  The nonvolatile solid-state memory 28 is, for example, a NAND-type FLASH memory card (Memory Stick, Compact Flash, SD Card, etc.) that employs a FAT file system, and has a predetermined address (hereinafter referred to as a predetermined address) for each predetermined data size (page). , Called a logical page number). The nonvolatile solid-state memory 28 is a memory that requires an erasing operation of data written in a target page when data is written.

  The nonvolatile solid-state memory 28 and the recording medium 20 are arranged on the same address space (logical block address (LBA)) while having a partially overlapping area (overlap area), as will be described later. Yes. The control unit 26 performs data read / write operations on the nonvolatile solid-state memory 28 and the recording medium 20 using the addresses. Note that the configuration of the bus connecting the memory control unit 30, the buffer memory 27, and the nonvolatile solid-state memory 28 shown in FIG. 1 is an example, and is appropriately changed based on the interface with the memory. It is.

  The page buffer 29 is disposed between the nonvolatile solid-state memory 28 and the memory control unit 30 and efficiently processes the transfer in units of pages performed between the buffer memory 27 and the nonvolatile solid-state memory 28. Used for. The page buffer 29 is also used when copying data in the nonvolatile solid-state memory 28 to another location in the nonvolatile solid-state memory 28 without going through the buffer memory 29. The data recording / reproducing apparatus 2 may have a configuration that does not include the page buffer 29. However, as will be described in detail later, it is preferable that the data recording / reproducing device 2 is provided in order to perform efficient garbage collection.

  The memory control unit 30 writes data supplied from the host device 1 to the recording medium 20 or the nonvolatile solid-state memory 28 or writes to the recording medium 20 or the nonvolatile solid-state memory 28 when the AV mode is selected. When transmitting the stored data to the host device 1, it is determined whether garbage collection is necessary for the nonvolatile solid-state memory 28, and if necessary, garbage collection is performed.

  Here, the operation of the memory control unit 30 will be described. The nonvolatile solid-state memory 28 is a 1 GBit flash memory (Block Size = 128 KB, Page Size = 2 KB), has 1024 blocks, and a total of 65536 pages. Further, as shown in FIG. 3, the physical page number indicates a block with upper 10 bits (“0x000” to “0x3FF”) and indicates an offset within the block with lower 6 bits (“0x00” to “0x3F”). Here, “x” represents a hexadecimal system. Further, in the NAND flash memory, a defective block must be replaced, so that some blocks must be left for its use. In FIG. 3, 16 blocks having block numbers “0x3F0” to “0x3FF” are assigned thereto. Therefore, the logical page number indicates the block in the upper 10 bits (“0x000” to “0x3EF”) and indicates the offset within the block in the lower 6 bits (“0x00” to “0x3F”).

  Further, in the nonvolatile solid-state memory 28, predetermined write-once processing (Wear Leveling) is performed in order to erase each block as uniformly as possible and write data to each page as uniformly as possible. In the data recording / reproducing apparatus 2, in order to perform this write-once processing, a table 1 in which a physical page number corresponding to a logical page number is recorded, and a flag (unused “ Table 2 in which “0” is displayed, “1” is displayed as valid, and “2” is displayed as invalid is recorded. Therefore, the memory control unit 30 can know the currently invalid page by rewriting data by referring to the table 2. Further, the data recording / reproducing apparatus 2 introduces a “pointer” indicating a page used when writing the next data.

<Configuration of host device>
The host device 1 also includes an interface control unit 40 that transmits / receives data to / from the data recording / reproducing device 2 via the interface 3, a CPU 41 that performs predetermined arithmetic processing, and a memory 42 that is used for arithmetic operations by the CPU 41. . The host device 1 is, for example, an application device such as a video camera, a digital camera, or a music player that efficiently performs recording / playback processing by taking advantage of the advantages of the data recording / playback device 2.

  The CPU 42 uploads each data stored in the boot area, the FAT area, and the directory area, which is management data recorded in the system area of the disk 20, to the memory 42 by executing a predetermined processing procedure when the power is turned on. Then, various commands are transmitted to the data recording / reproducing apparatus 2 by setting parameters based on the uploaded data.

<Writing new data>
Here, writing of new data will be described with reference to FIG. FIG. 4 shows an example of writing to the logical page number “0x001_00”. 4A-1 and 4A-2 are tables 1 showing the correspondence between the logical page numbers and the physical page numbers of the non-volatile solid-state memory 28, and FIGS. ) Is a table 2 showing the correspondence between block numbers and flags, and FIGS. 4C-1 and 4C-2 are pointers. Note that “x” in the figure means any value of (0, 1, 2).

  Since the pointer indicates “0x002_01” (FIG. 4 (C-1)), the memory control unit 30 writes data therein. Next, the memory control unit 30 puts “0x002_01” into the physical page number corresponding to “0x001_00” in Table 1 (FIG. 4 (A-2)). At the same time, the memory control unit 30 enables the flag corresponding to the physical page number “0x002_01” in the table 2, that is, changes the flag from “0” to “1” (FIG. 4 (B-2)). Further, the memory control unit 30 increments the pointer and sets it to “0x002 — 02” (FIG. 4 (C-2)).

<Rewriting data>
Next, the case of rewriting data will be described with reference to FIG. In FIG. 5, the data written in the logical address number “0x001_01” is rewritten. Since the pointer indicates “0x003 — 02” (FIG. 5 (C-1)), the memory control unit 30 writes to the pointer. Next, the memory control unit 30 changes the physical page number corresponding to “0x001_03” in Table 1 from “0x002_03” to “0x003_02” (FIG. 5 (A-2)), and at the same time, the physical page number “ The flag corresponding to “0x002_03” is invalid, that is, the flag is changed from “1” to “2”, and the flag corresponding to the written physical page number “0x003_02” is valid, that is, the flag is changed from “0” to “0”. 1 ”(FIG. 5B-2). Further, the memory control unit 30 increments the pointer by one and sets it to “0x003_03” (FIG. 5 (C-2)).

  In this way, if data writing continues, invalid pages gradually increase, and eventually there are no usable pages. Therefore, the memory control unit 30 moves the valid data to another block, invalidates all the pages in one block, and then performs a process of erasing and increasing the usable area, so-called garbage collection. Here, garbage collection will be described with reference to FIGS. 6 and 7. 6 and 7, it is assumed that there are four pages in one block for convenience of explanation.

<About garbage collection>
As shown in FIG. 6, the memory control unit 30 writes data from logical pages “0x000_1” to “0x002_1” (FIG. 6A-1), and then rewrites logical pages “0x000_0” and “0x000_1”. Furthermore, garbage collection is executed by deleting logical pages “0x001_2” and “0x002_3”. As can be seen from the table 2, there are invalid pages in the block 1 and the block 2, and these are the objects of garbage collection (FIG. 6 (B-2)).

  Further, the memory control unit 30 executes garbage collection in the order of the block numbers “0x000” and “0x001” from the states shown in FIGS. 6A-2, B-2, and C-2 ( 7 to 9). 6A-2, B-2, and C-2 and FIGS. 7A-2, B-2, and C-2 are the same.

  The memory control unit 30 copies the two valid pages with the block number “0x000” (the flag indicates “1”) to the physical page numbers “0x003_0” and “0x003_1” given by the pointers, so that the table 1 and the table 2 is updated as appropriate, and the pointer is set to “0x003_2” (step S1) (FIGS. 7A-3, B-3, and C-3). Thereafter, the memory control unit 30 deletes the block number “0x000” in which all pages in the block are invalid, and updates the table 2 (step S2) (FIG. 8 (A-4), (B -4) and (C-4)). Next, two valid pages in the block number “0x001” (the flag indicates “1”) are copied to the physical page numbers “0x003_2” and “0x003_3” given by the pointer, and Table 1 and Table 2 are copied. Is appropriately updated, and the pointer is set to “0x004 — 0” (step S3) (FIGS. 8A-5, B-5, and C-5). Thereafter, the memory control unit 30 deletes the block number “0x001” in which all pages in the block are invalid, and updates the table 2 (step S4) (FIG. 9 (A-6), (B -6) and (C-6)). Therefore, new data can be written to the pages belonging to the block number “0x000” and the block number “0x001” through steps S1 to S4.

<Storage space of nonvolatile solid-state memory 28 and recording medium 20>
Here, how the storage spaces of the nonvolatile solid-state memory 28 and the recording medium 20 are arranged in the data recording / reproducing apparatus 2 will be described with reference to FIG.

  As shown in FIG. 10, the storage space for the data recording / reproducing apparatus 2 includes a system area E, a disk cache area F, a user area G1, a user area G2, and a user area G3 for the data recording / reproducing apparatus 2. It is composed of The user areas G1 to G3 are allocated to the LBA space viewed from the host device 1.

  The system area E is composed of a nonvolatile solid-state memory 28, and is used by the CPU 31 to store boot codes and various tables, or as an area for secondary defect replacement processing.

  The disk cache area F is composed of the recording medium 20 and is used for the purpose of temporarily storing data. In the example shown in FIG. 10, the capacity of the disk cache area F is 128 Mbytes. The host device 1 cannot perform writing by designating an address directly to the disk cache area F.

  The user area G1 is composed of a nonvolatile solid-state memory 28, and a part or all of the user area G1 is backed up using the recording medium 20. The user area G1 includes a reserved area including an MBR (Master Boot Record) and a PBR (Partition Boot Record), and a FAT (File Allocation Table) area. The MBR is a sector of LBA “0” when viewed from the host device 1 and records a bootstrap code and a partition table.

  The user area G2 is composed of the recording medium 20, and stores directory items D for managing file information and actual data. Prior to FAT32, only the root directory was divided as a separate area. In the directory item D, information on file name, extension, attribute, latest update time, start cluster number, and file size is stored for each directory (each file).

  The user area G3 is composed of a nonvolatile solid-state memory 28, and part or all of the user area G3 is backed up using the recording medium 20. Further, the user area G3 is normally set so that data cannot be written from the host device 1, and only when a special mode (AV mode) is selected, the user area G3 is under the management of the data recording / reproducing device 2 itself. This is an area where data can be written.

  In FIG. 10, the nonvolatile solid-state memory 28 is assumed to be composed of two modules (Module 1 and Module 2). That is, pages with logical page numbers “00000h” to “0ffffh” belong to Module 1, and pages with logical page numbers “10000h” to “1ffffh” belong to Module 2. Module 1 and Module 2 can independently perform a Program (page unit write operation) and an erase operation.

  Here, in the data recording / reproducing apparatus 2, a method of executing garbage collection without affecting the data transfer while data is being written and read is described with reference to the flowcharts of FIGS. I will explain. First, the case of writing data will be described.

<About garbage collection when writing data>
When performing a data write operation in the AV mode, the host device 1 issues a command (Set Write File Parameter) shown in FIG. 12A to the data recording / reproducing device 2, and the data recording / reproducing device 2. Receives the recording start cluster number from. The data recording / reproducing apparatus 2 returns a command (Set Write File Parameter) shown in FIG.

  As shown in FIG. 11, the control unit 26 checks whether or not the parameter MP in the command supplied from the host device 1 is “1” (step S11). When the parameter MP is not “1”, the control unit 26 controls the servo control unit 24 and the read / write channel unit 25 to write the data supplied from the host device 1 to the recording medium 20 (step S12). When the parameter MP is set to “1”, the data supplied from the host device 1 is written in the user area G3 (nonvolatile solid-state memory 28).

  The memory control unit 30 determines whether there is free space in the user area G3 (step S13). If there is no free space, the host device 1 is notified to that effect (step S14).

  If the memory control unit 30 determines that there is a free area in the user area G3, it sends the file recording start cluster number to the host apparatus 1 (step S15).

  Next, the memory control unit 30 checks whether garbage collection is necessary for the nonvolatile solid-state memory 28 (step S16). When the memory control unit 30 determines that garbage collection is necessary in the process of step S16, that is, in all the nonvolatile solid-state memories 28, the number of blocks that require garbage collection is greater than a predetermined number. When the number of blocks requiring garbage collection is larger than the predetermined number, or when it is necessary to use the memory for reasons such as averaging the number of rewrites, garbage collection is performed on the nonvolatile memory that performs writing. Is executed (step S17).

  In addition, when the memory control unit 30 determines in the step S16 that garbage collection is not necessary, that is, the number of blocks that require garbage collection in a part of the nonvolatile solid-state memory 28 is greater than a predetermined number. If there are many, data is written avoiding them (step S18).

  Further, when the garbage collection is executed, the control unit 26 temporarily writes the data supplied from the host device 1 in the disk cache area of the recording medium 20 (step S19). Further, the control unit 26 creates a correspondence table (pointer) that gives correspondence between the file recording start cluster number and the address of the disk cache area to be used (step S20). The data recording / reproducing apparatus 2 may be composed of a plurality of nonvolatile solid-state memories 28. When configured in this way, the data supplied from the host device 1 includes other nonvolatile solid-state memory 28 that does not require garbage collection, that is, the number of blocks that require garbage collection is greater than a predetermined number. It is recorded for many nonvolatile solid-state memories 28.

  Further, the memory control unit 30 receives the permission of the host device 1 based on the correspondence table generated in the process of step S20 after the garbage collection is completed, or autonomously, the disk cache of the recording medium 20 Data written in the area is written back to the nonvolatile solid-state memory 28, and the address information is updated accordingly.

  The memory control unit 30 updates the number of usable blocks in the nonvolatile solid-state memory 28 (step S21), and determines whether all data has been written (step S22). If the memory control unit 30 determines in the step S22 that all data has not been written, the process returns to the step S16.

  Here, in the case where the nonvolatile solid-state memory 28 of the data recording / reproducing apparatus 2 is composed of two modules (Module 1 and Module 2), for example, Module 1 has a predetermined number of blocks that require garbage collection. More modules, i.e., modules that need garbage collection, and Module2 is a module that has fewer than a predetermined number of blocks that require garbage collection, i.e., modules that do not require garbage collection. The operation of the memory control unit 30 when writing data to the nonvolatile solid-state memory 28 will be described with reference to FIG.

  The memory control unit 30 determines whether or not garbage collection is necessary for Module1 and Module2, and recognizes that Module1 needs garbage collection and Module2 does not need garbage collection. The memory control unit 30 connects Module 1 and the page buffer 29 and executes garbage collection for Module 1. The memory control unit 30 connects Module 2 and the buffer memory 27 and writes data to Module 2.

  In this manner, the data recording / reproducing apparatus 2 according to the present invention can write data supplied from the host apparatus 1 to another recording area during the execution of garbage collection. However, the data transfer from the host device 1 is not stopped, and even though the nonvolatile solid-state memory 28 has a sufficient storage capacity, invalid pages (pages on which data cannot be written) increase, and data is being written. In this case, it is possible to avoid the phenomenon that the number of blocks to be written becomes insufficient.

<About garbage collection when reading data>
Next, when performing a data read operation in the AV mode, the host device 1 issues a command (Set Read File Parameter) shown in FIG. 14A to the data recording / reproducing device 2 to record the data. The playback device 2 is notified of the start cluster address of the file to be read. The data recording / reproducing apparatus 2 returns a command (Set Read File Parameter) shown in FIG.

  As shown in FIG. 15, the control unit 26 recognizes the start cluster address of the file to be read based on the command supplied from the host device 1, and determines whether to request access to the user area G3 ( Step S31).

  If the control unit 26 determines in the step S31 that access to the user area G3 is not requested, the control section 26 reads data from the user area G2 (recording medium 20), and reads the read data to the host device. 1 (step S32).

  If the memory control unit 30 determines in the step S31 that access to the user area G3 is requested, the memory control unit 30 confirms whether the nonvolatile solid-state memory 28 needs to be garbage collected. (Step S33). In the step S33, when a plurality of nonvolatile solid-state memories 28 are mounted on the data recording / reproducing apparatus 2, the number of blocks that require garbage collection is determined for each nonvolatile solid-state memory 28. Check if it is over the set value.

  If the memory control unit 30 determines in the step S33 that garbage collection is unnecessary, the memory control unit 30 reads data from the user area G3 and transfers it to the host device 1 (step S34).

  If the memory control unit 30 determines in the step S33 that the garbage collection is necessary, the memory control unit 30 stores the data to be read into the nonvolatile solid-state memory 28 to be garbage collected. Whether or not is written is determined (step S35).

  When the memory control unit 30 determines in step S35 that the nonvolatile solid-state memory 28 in which the data to be read is written is the target of garbage collection, the block to which the data belongs The whole is read to the buffer memory 27 (step S36), garbage collection is executed for the nonvolatile solid-state memory 28 (step S37), and the data read to the buffer memory 27 is read in parallel with the step S37. (Step S38).

  Further, the memory control unit 30 updates the number of usable blocks in the nonvolatile solid-state memory 28 (step S39), and determines whether all data has been read (step S40). If the memory control unit 30 determines in the step S40 that all data has not been read, the process returns to the step S33.

  Here, in the case where the nonvolatile solid-state memory 28 of the data recording / reproducing apparatus 2 is composed of two modules (Module 1 and Module 2), for example, the file A requested to be read from the host apparatus 1 is data fb1 and The data fb2, the data fb3, the data fb4, and the data fb5 are configured. The data fb1 and the data fb4 are written in Module1, and the data fb2, the data fb3, and the data are stored in Module2. The operation of reading the file A by the memory control unit 30 when fb5 is written will be described with reference to FIGS. Note that the AV mode is selected as the mode. Module 1 is a module in which the number of blocks that require garbage collection is larger than a predetermined number, that is, a module that requires garbage collection, and Module 2 has a predetermined number of blocks that require garbage collection. Fewer modules, i.e., modules that do not require garbage collection.

  The memory control unit 30 connects Module1 and the buffer memory 27, and transfers the data fb1 and data fb4 read from Module1 to the buffer memory 27 (FIG. 16). Next, the memory control unit 30 connects Module 2 and the buffer memory 27 and transfers data fb2, data fb3, and data fb5 read from Module 2 to the buffer memory 27 (FIG. 17).

  The memory control unit 30 reads the data fb1 to fb5 written in the buffer memory 27 and transfers the data to the host device 1, and simultaneously connects Module1 and the page buffer 29 to execute garbage collection for Module1.

  Note that the amount of data to be transferred to the buffer memory 27 is determined so as to ensure the combined time of data transfer and garbage collection. However, the transfer amount is determined for each fine operation break, for example, for each page transfer. The data may be transferred to the buffer memory 27.

  In this way, in the data recording / reproducing apparatus 2 according to the present invention, arbitrary data is read in response to a request from the host apparatus 1, the read data is transferred to the host apparatus 1, and in parallel, the nonvolatile solid-state memory A garbage collection for 28 can be performed.

  Further, the data recording / reproducing apparatus 2 according to the present invention can cope with a case where the host apparatus 1 requests data reading and data writing simultaneously. Since the data recording / reproducing apparatus 2 always manages the page status (unused, valid, invalid) of each block of the individual nonvolatile solid-state memory 28, when data writing is requested, it is garbage collected. Data is written to other non-volatile solid-state memory 28 that does not require garbage collection or disk cache area of recording medium 20, and garbage collection is required in parallel. Garbage collection is executed on the nonvolatile solid-state memory 28.

  In addition, the data recording / reproducing apparatus 2 pre-loads the host device from the nonvolatile solid-state memory 28 that is the object of garbage collection so that the time required for garbage collection can be secured when data reading is requested. 1 is read out and transferred to the buffer memory 27. After that, garbage collection is performed on the nonvolatile solid-state memory 28, and the data is written to the buffer memory 27 in parallel. Data to be transferred to the host device 1.

  The data recording / reproducing apparatus 2 configured as described above includes a recording medium 20 having a predetermined capacity, a nonvolatile solid-state memory 28 having a predetermined capacity that forms a storage space with the recording medium 20, and a recording medium 20. A control unit 26 that controls access, a buffer memory 27 having a predetermined capacity, and a memory control unit 30 that controls access to the nonvolatile solid-state memory 28, and uses a nonvolatile solid-state memory 28 (NAND Flash memory) In the AV mode, garbage collection, which cannot be avoided, can be executed in parallel without interrupting the writing of data to the other nonvolatile solid-state memory 28 or the recording medium 20, and to the host device 1. It can be executed in parallel without affecting the data transfer.

  In addition, since the data recording / reproducing apparatus 2 can provide the host apparatus 1 with a stable data transfer rate, for example, when viewed from the application side, a drop during movie reproduction or recording during data recording is possible. Problems such as mistakes are reduced. Further, since the necessity of Background Garbage Collection (performing garbage collection when data is not accessed) generally executed by the existing data recording / reproducing apparatus 2 is reduced, There is an advantage that power consumption is reduced when not accessing.

  In this embodiment, the HDD is described as a specific example of the storage device. However, if the storage device is a randomly accessible storage device, the same processing is possible even with an optical disk such as a CD or DVD. is there. In the description, the FAT file system is used, but any system that manages data as files can be applied.

It is a block diagram which shows the structure of the data recording / reproducing apparatus in embodiment of this invention. It is a schematic diagram which shows the LBA space for description of a file system. It is a schematic diagram which shows the address space of a non-volatile solid-state memory. It is a figure where it uses for description about operation | movement (writing of new data) of a memory control part. It is a figure with which it uses for description about operation | movement (data rewriting) of a memory control part. It is a 1st figure with which it uses for description about the operation | movement of the garbage collection by a memory control part. It is a 2nd figure with which it uses for description about operation | movement of the garbage collection by a memory control part. It is a 3rd figure with which it uses for description about the operation | movement of the garbage collection by a memory control part. It is a 4th figure with which it uses for description about the operation | movement of the garbage collection by a memory control part. It is a figure where it uses for description about the storage space of a non-volatile solid-state memory and a recording medium. 5 is a flowchart for explaining a data writing operation by the data recording / reproducing apparatus according to the present invention. It is a schematic diagram of Set Write File Parameter transmitted / received between the data recording / reproducing apparatus and the host apparatus during the data writing operation. It is a figure where it uses for description about operation | movement of the memory control part at the time of writing data in a non-volatile solid-state memory. It is a schematic diagram of Set Read File Parameter transmitted / received between the data recording / reproducing device and the host device during the data reading operation. 5 is a flowchart for explaining a data read operation by the data recording / reproducing apparatus according to the present invention. It is the 1st figure with which it uses for description about operation | movement of the memory control part at the time of reading data from a non-volatile solid-state memory. It is a 2nd figure with which it uses for description about operation | movement of the memory control part at the time of reading data from a non-volatile solid memory.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Host apparatus, 2 Data recording / reproducing apparatus, 20 Recording medium, 21 Head part, 22 Head drive part, 23 Recording medium drive part, 24 Servo control part, 25 Read / write channel part, 26 Control part, 27 Buffer memory, 28 Nonvolatile Solid state memory, 29 page buffer, 30 memory control unit, 31 arithmetic processing unit (CPU), 32 memory, 33 interface control unit

Claims (13)

A data recording apparatus having a first data access mode to which a host apparatus is connected and data is accessed in accordance with the control of the host apparatus, and a second data access mode in which data is accessed by its own control In
A non-volatile solid-state memory that has a first data area to which a first physical address is attached, and that requires an erasing operation of the area to be written when writing data to the first data area;
A storage medium that has a second data area to which a second physical address is assigned, and does not require an erasing operation of the area to be written when data is written to the second data area;
Connection means to which the host device is connected;
Writing means for writing data transferred from the host device to an arbitrary area of the nonvolatile solid-state memory or an arbitrary area of the storage medium;
When the second data access mode is selected and data is transferred from the host device connected to the connection means, or the writing means writes data into the nonvolatile solid-state memory or the recording medium And determining means for determining whether garbage collection is necessary for the nonvolatile solid-state memory,
Garbage collection executing means for executing garbage collection on the nonvolatile solid-state memory;
The non-volatile solid-state memory controls the writing unit to write the data transferred from the host device to a predetermined area of the storage medium when the determining unit determines that garbage collection is necessary. And a control means for controlling the garbage collection execution means so as to execute garbage collection. When a plurality of the nonvolatile solid-state memories are provided,
When the second data access mode is selected and data is transferred from the host device connected to the connection unit, the determination unit determines which non-volatile type from the plurality of non-volatile solid memories. Determine if solid memory needs garbage collection,
The control means determines that the data transferred from the host device is not subject to garbage collection when the determination means determines that garbage collection is necessary for one nonvolatile solid-state memory. The writing means is controlled to write to a predetermined area of the nonvolatile solid-state memory, and the garbage collection executing means is controlled to execute garbage collection on the one nonvolatile solid-state memory. The data recording apparatus according to claim 1.   The writing means includes a logical address for managing the first physical address and the second physical address, and a part of the first physical address and a part of the second physical address are the same. Based on an identification information table in which predetermined identification information is written for each logical address, the data transferred from the host device is stored in an arbitrary area of the nonvolatile solid-state memory or the storage 2. The data recording apparatus according to claim 1, wherein writing is performed in an arbitrary area of the medium. A data recording apparatus having a first data access mode to which a host apparatus is connected and data is accessed in accordance with the control of the host apparatus, and a second data access mode in which data is accessed by its own control In the data recording method of
When the second data access mode is selected and data is transferred from the host device, or has a first data area to which a first physical address is assigned, and the first data area has When data is being written, if data is being written to a nonvolatile solid-state memory that requires an erasing operation of an area to be written, it is determined whether garbage collection is necessary for the nonvolatile solid-state memory. A decision process;
If it is determined in the determination step that garbage collection is necessary, the data transferred from the host device has a second data area to which a second physical address is assigned, and the second A writing step of writing data in a predetermined area of a recording medium that does not require an erasing operation of the area to be written when writing data in the data area;
A data recording method comprising a garbage collection execution step of executing garbage collection on the nonvolatile solid-state memory in parallel with the data writing operation in the writing step. A data reproducing apparatus having a first data access mode in which a host device is connected and data is accessed according to the control of the host device, and a second data access mode in which data is accessed by its own control In
A non-volatile solid-state memory that has a first data area to which a first physical address is attached, and that requires an erasing operation of the area to be written when writing data to the first data area;
A storage medium that has a second data area to which a second physical address is assigned, and does not require an erasing operation of the area to be written when writing data to the second area;
A buffering memory used for buffering data;
Connection means to which the host device is connected;
Reading means for reading data from an arbitrary area of the nonvolatile solid-state memory or an arbitrary area of the storage medium in accordance with an instruction of the host device;
When the second data access mode is selected and the host device connected to the connection means is instructed to read data, it is determined whether garbage collection is necessary for the nonvolatile solid-state memory. A judgment means to
Garbage collection executing means for executing garbage collection on the nonvolatile solid-state memory;
When the determination means determines that garbage collection is necessary, the reading means is controlled to read the necessary data from the nonvolatile solid memory onto the buffering memory, and the nonvolatile solid memory is stored in the nonvolatile solid memory. And a control means for controlling the garbage collection executing means so as to execute garbage collection. When a plurality of the nonvolatile solid-state memories are provided,
When the second data access mode is selected and the host device connected to the connection means is instructed to read data, the determination means selects which nonvolatile solid-state memory from the plurality of nonvolatile solid-state memories. To determine whether garbage collection is required for
When the determination unit determines that garbage collection is necessary for one nonvolatile solid-state memory, the control unit stores data necessary for the one nonvolatile solid-state memory on the buffering memory. 6. The data reproducing apparatus according to claim 5, wherein said reading means is controlled to read, and said garbage collection executing means is controlled to execute garbage collection on said one non-volatile solid memory.   The reading means includes a logical address that manages the first physical address and the second physical address, and a part of the first physical address and a part of the second physical address are the same. Based on an identification information table composed of logical addresses and in which predetermined identification information is written for each logical address, in accordance with an instruction from the host device, an arbitrary area of the nonvolatile solid-state memory or an arbitrary storage medium 6. The data reproducing apparatus according to claim 5, wherein data is read from the area. A data reproducing apparatus having a first data access mode in which a host device is connected and data is accessed according to the control of the host device, and a second data access mode in which data is accessed by its own control In the data reproduction method of
When the second data access mode is selected and the host device is instructed to read data, the first data area has a first data area to which a first physical address is attached. A determination step of determining whether garbage collection is necessary for a nonvolatile solid-state memory that requires an erasing operation of an area to be written when data is written to
A read step of reading the necessary data from the nonvolatile solid-state memory onto the buffering memory when the determination step determines that garbage collection is necessary;
A data reproduction method comprising a garbage collection execution step of executing garbage collection on the nonvolatile solid-state memory in parallel with the data reading operation in the reading step. Data recording / reproduction having a first data access mode in which a host device is connected and data is accessed according to the control of the host device, and a second data access mode in which data is accessed under its own control In the device
A non-volatile solid-state memory that has a first data area to which a first physical address is attached, and that requires an erasing operation of the area to be written when writing data to the first data area;
A storage medium that has a second data area to which a second physical address is assigned, and does not require an erasing operation of the area to be written when data is written to the second data area;
A buffering memory used for buffering data;
Connection means to which the host device is connected;
Writing means for writing data transferred from the host device to an arbitrary area of the nonvolatile solid-state memory or an arbitrary area of the storage medium;
Reading means for reading data from an arbitrary area of the nonvolatile solid-state memory or an arbitrary area of the storage medium in accordance with an instruction of the host device;
When the second data access mode is selected and data is transferred from the host device connected to the connection means, or the writing means writes data into the nonvolatile solid-state memory or the recording medium A first determination means for determining whether garbage collection is necessary for the nonvolatile solid-state memory,
When the second data access mode is selected and the host device connected to the connection means is instructed to read data, it is determined whether garbage collection is necessary for the nonvolatile solid-state memory. A second determination means to:
Garbage collection executing means for executing garbage collection on the nonvolatile solid-state memory;
When the first determination means determines that garbage collection is necessary, the writing means is controlled to write the data transferred from the host device to a predetermined area of the storage medium, and the nonvolatile storage First control means for controlling the garbage collection execution means so as to execute garbage collection on the volatile solid-state memory;
When the second determination means determines that garbage collection is necessary, the read means is controlled to read the necessary data from the nonvolatile solid-state memory onto the buffering memory, and the nonvolatile A data recording / reproducing apparatus comprising: a second control unit that controls the garbage collection executing unit so as to execute garbage collection on a solid-state memory. When a plurality of the nonvolatile solid-state memories are provided,
The first determination unit is configured to select one of the plurality of nonvolatile solid-state memories when the second data access mode is selected and data is transferred from the host device connected to the connection unit. Determine which non-volatile solid-state memory needs garbage collection,
The first control means, when the first judging means judges that garbage collection is necessary for one nonvolatile solid-state memory, the data transferred from the host device is subject to garbage collection. The writing means is controlled to write in a predetermined area of another non-volatile solid-state memory, and the garbage collection execution means is controlled to execute garbage collection on the one non-volatile solid-state memory. The data recording / reproducing apparatus according to claim 9. When a plurality of the nonvolatile solid-state memories are provided,
The second determination unit is configured to store the plurality of nonvolatile solid-state memories when the second data access mode is selected and the host device connected to the connection unit is instructed to read data. Determine which non-volatile solid-state memory needs garbage collection,
When the second determination means determines that garbage collection is necessary for one nonvolatile solid-state memory, the second control means obtains data required from the one nonvolatile solid-state memory. 10. The read means is controlled to read data on the buffering memory, and the garbage collection execution means is controlled to execute garbage collection on the one nonvolatile solid-state memory. Data recording / reproducing apparatus. The writing means includes a logical address for managing the first physical address and the second physical address, and a part of the first physical address and a part of the second physical address are the same. Based on an identification information table in which predetermined identification information is written for each logical address, the data transferred from the host device is stored in an arbitrary area of the nonvolatile solid-state memory or the storage Write to any area of the media,
10. The reading means reads data from an arbitrary area of the nonvolatile solid-state memory or an arbitrary area of the storage medium in accordance with an instruction from the host device based on the identification information table. Data recording / reproducing apparatus. Data recording / reproduction having a first data access mode in which a host device is connected and data is accessed according to the control of the host device, and a second data access mode in which data is accessed under its own control In the data recording / reproducing method of the apparatus,
When the second data access mode is selected and data is transferred from the host device, or has a first data area to which a first physical address is assigned, and the first data area has When data is being written, if data is being written to a nonvolatile solid-state memory that requires an erasing operation of an area to be written, it is determined whether garbage collection is necessary for the nonvolatile solid-state memory. A first determination step;
If it is determined in the first determination step that garbage collection is necessary, the data transferred from the host device has a second data area to which a second physical address is attached, and A writing step of writing data in a predetermined area of a recording medium that does not require an erasing operation of the area to be written when writing data in the second data area;
A first garbage collection execution step of performing garbage collection on the nonvolatile solid-state memory in parallel with the data writing operation by the writing step;
A second determination step of determining whether or not garbage collection is necessary for the nonvolatile solid-state memory when the second data access mode is selected and an instruction to read data is issued from the host device;
A read step of reading the necessary data from the nonvolatile solid-state memory onto the buffering memory when it is determined that garbage collection is necessary in the second determination step;
A data recording / reproducing method comprising a second garbage collection execution step of executing garbage collection on the nonvolatile solid-state memory in parallel with the data reading operation in the reading step.

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