JP2015185024A - File system management device, control method of file system management device, and control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten processing time of data processing.SOLUTION: A file system management device includes: a block specifying part (23) for specifying a write block which is a block where data is written, and a part of an empty block which is a block where the data are not written, among a plurality of blocks; and a file processing part (24) for performing common data processing including at least either of reading or writing with respect to all of the specified blocks.

Description

  The present invention relates to a file system management apparatus for managing a file system having a data structure managed for each block.

  In recent years, as a method for managing data, file systems that are managed in units of blocks and have management information in units of groups including a plurality of blocks have been used (Non-Patent Documents 1 and 2). In a file system having such a data structure, Patent Document 1 discloses a technique for speeding up disk mirroring. In the technique described in Patent Document 1, it is determined whether each block is in use or free by using a bitmap table, and only the used block is subject to mirroring.

  Patent Document 2 discloses a technique that uses the same method as Patent Document 1 and encrypts only used blocks.

Japanese Patent Laying-Open No. 2005-284980 (released on October 13, 2005) JP 2009-15357 A (released January 22, 2009)

Ext4 (and Ext2 / Ext3) Wiki [online], [Search March 7, 2014], Internet <URL: https://ext4.wiki.kernel.org> Proceedings of the Linux Symposium July 23rd-26th, 2008 Ottawa, Ontario Canada [online], [March 7, 2014 search], Internet <URL: http://ols.fedoraproject.org/OLS/Reprints-2008/ (kumar-reprint.pdf)

  In general, in data processing including reading and writing, the number of times of reading and writing increases, and the processing time increases as the amount of data to be processed increases.

And since the technique of the said patent documents 1 and 2 makes only the used block the object of mirroring or encryption, depending on arrangement | positioning of the block in use and an empty block, the frequency | count of reading and writing of a block may be sufficient. Since it increases, processing time may increase. For example, as shown in “Group 3” in FIG. 12B, used blocks (indicated by “Used”) and empty blocks (indicated by “Free”) are alternately arranged. If only the existing blocks (S _{1 to} S ₄ ) are processed, the number of times of reading and writing will increase.

Further, when the entire group is a target of mirroring or encryption, the number of times of reading and writing is minimized, but the amount of data to be targeted is maximized, so that the processing time may also increase. For example, as shown in “Group 3” in FIG. 12A, if the entire group (S _group ) is a processing target, the amount of data to be processed is maximized.

  The present invention has been made in view of the above problems, and an object thereof is to realize a file system management apparatus or the like that shortens the processing time of data processing including at least one of reading and writing.

  In order to solve the above problems, a file system management apparatus according to an aspect of the present invention is a file system management apparatus that manages a file system having a data structure managed for each block. A block specifying means for specifying a writing block that is a block in which data is written and a part of an empty block that is a block to which data is not written, and for all of the blocks specified by the block specifying means, Data processing execution means for executing common data processing including at least one of reading and writing.

  According to one aspect of the present invention, it is possible to reduce the amount of data processing as compared with the case where data processing is executed on all blocks. In addition, since some of the free blocks are also subject to data processing, the number of reads and writes for data processing can be reduced compared to the case where data processing is performed only on write blocks. Play. Since the amount of data processing and the number of reads and writes can be reduced, the data processing can be made more efficient and the processing time can be shortened.

It is a block diagram which shows the principal part structure of the information processing apparatus which concerns on embodiment of this invention. It is a figure which shows the table used with the said information processing apparatus, (a) is a figure which shows a bitmap table, (b) is a figure which shows a 1st management table, (c) shows a 2nd management table. FIG. It is a figure for demonstrating the content of the process in the said information processing apparatus, (a) is a figure which shows the data amount in each process aspect, the frequency | count, and time, (b) is the largest empty area at the end of a group It is a figure which shows a case, (c) is a figure which shows the case where the largest empty area exists in the other than the end of a group. It is a flowchart which shows the flow of the encryption process in the said information processing apparatus. It is a flowchart which shows the flow of a 1st encryption process. It is a flowchart which shows the flow of a 2nd encryption process. It is a figure for demonstrating a 1st encryption process, (a) is a figure which shows preparation of a 1st management table, (b) is a figure which shows file addition, (c) shows file deletion. It is a figure and (d) is a figure which shows an encryption process. It is a figure for demonstrating a 2nd encryption process, (a) is a figure which shows preparation of a 1st management table, (b) is a figure which shows file addition, (c) shows file deletion. It is a figure and (d) is a figure which shows an encryption process. It is a flowchart which shows the flow of the mirroring process in the said information processing apparatus. It is a flowchart which shows the flow of a 1st mirroring process. It is a flowchart which shows the flow of a 2nd mirroring process. It is a figure for demonstrating the subject of this invention, (a) is a figure which shows the case where the whole group is made into a process target, (b) is a figure which shows the case where only the used block is made into a process target. It is.

Embodiment 1
〔Overview〕
Embodiments of the present invention will be described below with reference to FIGS. An information processing apparatus (file system management apparatus) 1 according to the present embodiment is an apparatus that processes a file system that is managed for each block and that has management information for each group including a plurality of blocks. In the present embodiment, the information processing apparatus 1 is assumed to be a portable information terminal including the display unit 12, the operation receiving unit 13, and the communication unit 14, but is not limited thereto. These members are not essential, and any device can be used as long as it is a device that processes the file system described above.

  The information processing apparatus 1 according to the present embodiment shortens the processing time by specifying an appropriate processing target block according to the use state of the block. More specifically, the processing time is shortened by changing the block to be processed in accordance with the number of used blocks, regardless of the block usage state.

[Configuration of Information Processing Apparatus 1]
FIG. 1 is a block diagram showing a main configuration of the information processing apparatus 1. As illustrated in FIG. 1, the information processing apparatus 1 includes a control unit 10, a storage unit 11, a display unit 12, an operation reception unit 13, a communication unit 14, and a RAM 26.

  The storage unit 11 includes a disk 31, and a file system 32 is stored in the disk 31. Although the number of the disks 31 is one here, the number is not limited to this, and any number may be used. The storage unit 11 includes a nonvolatile storage device such as a flash memory or a ROM (Read Only Memory). In addition to the data to be processed, the storage unit 11 stores various programs, various operation setting values, various data, and the like.

  The file system 32 is a data structure managed for each block and including management information for each group including a plurality of blocks, and includes a bitmap table 33 and data 34. The bitmap table 33 manages the usage state of the data 34 and indicates the configuration of the data 34. An example of the bitmap table 33 is shown in FIG. In the example illustrated in FIG. 2A, there are blocks from “# 1 to #N” and groups from “Group1 to Group3”. Blocks # 1 and # 2 of Group 1 are in use (indicated by “1”), and blocks # 3, # 4, # 5, # 6, and #N are empty (indicated by “0”). It has been shown. Similarly, blocks # 5 and # 6 of Group 2 are in use, and blocks # 1 to # 4 and #N are empty. Further, it is indicated that blocks # 1, # 2, and # 4 of Group 3 are in use, and blocks # 3, # 5, # 6, and #N are free.

  The RAM 26 is a volatile storage device and includes a first management table 27 and a second management table 28. FIG. 2B shows an example of the first management table 27, and FIG. 2C shows an example of the second management table 28. As shown in FIG. 2B, the first management table 27 indicates how many free blocks continue from the end in each group (free block number). In the example of FIG. 2B, the Group 1 indicates that empty blocks continue from the end to the block # 3. Further, Group 2 indicates that an empty block continues from the end to block # 15, and Group 3 indicates that an empty block continues from the end to block # 16.

  Further, as shown in FIG. 2 (c), the second management table 28 includes a position where the number of consecutive free blocks (max_free_block) and a position of a free block (such as free block_1_start to end) in each group. Is shown.

  In the example of FIG. 2C, for Group 1, blocks # 3 to # 18 are empty blocks, and the continuous blocks # 3 to # 18 have the largest number of free blocks that continue. Is shown. For Group 2, blocks # 1 to # 4 and # 12 to # 13 are empty blocks, and consecutive blocks # 1 to # 4 (free_block_2) have the largest number of free blocks. Is shown. For Group 3, blocks # 3, # 5 to # 6,... Are free blocks, and the continuous block indicated by (free_block_5) is the maximum number of continuous free blocks. .

  The control unit 10 executes data processing (for example, encryption processing) including reading and writing with respect to the file system 32 and executes various processes in the information processing apparatus 1. The control unit 10 includes a bitmap table creation unit 21, a free block number determination unit (free block number determination unit) 22, a block identification unit (block identification unit) 23, a file processing unit (data processing execution unit) 24, and a management table A creation unit 25 is included.

  The bitmap table creation unit 21 confirms which block is in use and which block is free for each group of data 34, creates a bitmap table 33, and stores it in the disk 31.

  The free block number determination unit 22 counts the number of free blocks of the data 34 from the bitmap table 33 for each group, and determines whether or not the first predetermined value is exceeded. Then, the block determination unit 23 is notified of the determined result.

  The block specifying unit 23 specifies a block to be processed by the file processing unit 24 for each group, and notifies the file processing unit 24 of the specified block. More specifically, when the determination result notified from the free block number determination unit 22 does not exceed the first predetermined value, only the block in use is specified and notified to the file processing unit 24. Further, when the determination result notified from the free block number determination unit 22 is equal to or greater than the first predetermined value, referring to the second management table 28, the largest number of consecutive free blocks is the second predetermined value. Judge whether to exceed. If the second predetermined value is not exceeded, the first management table 27 is referred to identify a free block continuous from the end for each group, and notify the file processing unit 24 of it. If the value is equal to or greater than the second predetermined value, the second management table 28 is referenced to identify the largest free block that is continuous for each group and notify the file processing unit 24 of it.

  The file processing unit 24 performs processing (encryption processing) on the identified block notified from the block identifying unit 23. Here, only the blocks in use are notified from the block specifying unit 23, and when these blocks are encrypted, the third encryption processing is performed, and the free blocks continuous from the end for each group are notified from the block specifying unit 23. The first encryption processing is performed when these blocks are encrypted, and the largest one of the free blocks continuous for each group is notified from the block specifying unit 23, and the second encryption is performed when these blocks are encrypted. This is called encryption processing. Further, the encryption process itself can be performed by a known technique, and thus the description thereof is omitted.

  The management table creation unit 25 creates the first management table 27 and the second management table 28 with reference to the bitmap table 33 and stores them in the RAM 26.

  The display unit 12 displays various information. The display unit 12 can be realized by an LCD, an organic EL display, or the like. The operation reception unit 13 receives various operations on the information processing apparatus 1. In addition, the structure which can perform the display part 12 and the operation reception part 13 in common with a touchscreen etc. may be sufficient. The communication unit 14 performs communication between the information processing apparatus 1 and an external network. As described above, the display unit 12, the operation receiving unit 13, and the communication unit 14 are not essential components.

[Action / Effect]
As described above, the information processing apparatus 1 according to the present embodiment uses a method of specifying a block to be encrypted by the number of unused blocks included in a group and the size of consecutive unused blocks. Make it different. As a result, the time required for the encryption process can be shortened. This will be described with reference to FIG.

FIG. 3 is a diagram showing the amount of write data, the number of times of writing, and the processing time for each encryption process (encryption process for the entire disk, third encryption process, first encryption process, and second encryption process). . In addition, the meaning of each parameter shown to Fig.3 (a) is as follows.
S _group : Size of one group S _max : Maximum size writable at one time S _i : Size of the i-th continuous writing area S ′ _i : Remainder of dividing S _i by S _max > S ′ _i
a _i : quotient obtained by dividing S _i by S _max b _i : 1 when there is a remainder when S _i is divided by S _max , 0 if there is no remainder
C _i = a _i + b _i : Number of times of writing necessary only for S _i writing C _group = S _group / S _max : Minimum number of times of writing required for writing for one group f (S _i ): It takes to write S _i Processing time f (S _max ): Processing time related to writing of S _max For example, when there are empty blocks (which may be one or continuous) at the top and the bottom of the group, S _A <S _B , S _A <S _C , C _A <C _B , C _A <C _C , and the processing time of the third encryption process is shortened.

Further, if the used block and the free blocks is in the _{alternate, S A <S B, S} A <S C , and the amount the write data in the third encryption process, in the first, second encryption process It becomes smaller than the amount of write data. On the other hand, since C _A > C _B and C _A > C _C , the number of times of writing is smaller in the first and second encryption processes than in the third encryption process. Therefore, if the number of times of writing increases, the processing time is shorter in the first and second encryption processes.

Further, when the in-use blocks and the empty blocks are alternated, and there is the largest continuous empty block other than the end of the group (FIG. 3C), always in the second encryption process. The amount of write data becomes small (S _B > S _C ). This is because the first encryption process encrypts data other than the end of the group, and the second encryption process encrypts data other than the largest continuous empty block.

When there is the largest continuous free block at the end of the group (FIG. 3B), there is no difference in the amount of write data between the first encryption process and the second encryption process (S _B = S _C ). When the amount of write data is the same, the number of writes is always smaller in the first encryption process (C _B <C _C ).

In addition, when there is an empty block (which may be one or continuous) only at the end of the group, S _A = S _B = S _C , C _A = C _B = C _C , and the amount of write data and the number of writes Both are the same, and the write processing time is also the same (f (S _A ) = f (S _B ) = f (S _C )).

[Encryption process flow]
Next, the flow of encryption processing in the information processing apparatus 1 will be described with reference to FIGS. 4 to 6 are flowcharts showing the flow of the encryption process.

  As shown in FIG. 4, first, the bitmap table creation unit 21 creates a bitmap table 33 in the file system 32 with reference to the data 34 (S1). Thereafter, when there is a file creation (S2) or a file deletion (S4) (YES in S2 and S4), the bitmap table creation unit 21 updates the bitmap table 33 (S3).

  When the file processing unit 24 starts disk encryption (YES in S5), the bitmap table 33 of the group i (group i) is read (S6), and the free block number determination unit 22 refers to the bitmap table 33. Then, it is determined whether or not there are N (threshold) or more empty blocks in the same group (S7). If the number of empty blocks in the same group is less than N (NO in S7), the process proceeds to “third encryption process” in step S8. The third encryption process is a process in which only in-use blocks are targeted for encryption.

  On the other hand, if there are N or more empty blocks in the same group (S7 YES), the block specifying unit 23 determines whether or not the size of the largest empty area (continuous empty block) in the group is F or more ( S9). If the size of the maximum free area in the group is F or larger (YES in S9), the process proceeds to “second encryption process” in step S11. If the size of the maximum free area in the group is less than F (NO in S9), the process proceeds to “first encryption process” in step S10.

  Thereafter, encryption processing is performed for all groups, and when encryption processing is completed for all groups (NO in S12), the encryption processing is ended.

Next, the flow of the first encryption process will be described with reference to FIG. First, the management table creation unit 25 creates the first management table 27 of the group i (Group i) with reference to the bitmap table 33 (S101). Next, the block specifying unit 23 refers to the first management table 27 and determines whether or not the target block is the first block of empty blocks continuous from the end in the group (S102, block specifying). Step). Then, if it is not the first of the free blocks continuous from the end (YES in S102), the file processing unit 24 reads the block and performs encryption processing on the RAM 26 (S103, data processing execution step). Then, the file processing unit 24 determines whether the amount of unencrypted data that has been encrypted in the RAM 26 is equal to or greater than the maximum size (S _max ) that can be written at one time (S 104), and is less than S _max. If so (NO in S104), the process of step S102 is performed on the next block. On the other hand, if it is equal to or greater than _Smax (YES in S104), unwritten encrypted data is written to the disk 31 for _Smax (S105).

  In step S102, when the target block is the first block among the free blocks continuous from the end (NO in step S102), the file processing unit 24 determines whether there is an unwritten block that has been encrypted in the RAM 26. If there is an unwritten block (YES in S106), the unwritten block is written to the disk 31 (S107). Then, the first encryption process is terminated. If there is no unwritten block (NO in S106), the first encryption process is terminated.

  Next, the flow of the second encryption process will be described with reference to FIG. First, the management table creation unit 25 creates the second management table 28 with reference to the bitmap table 33 (S201). Then, the management table creation unit 25 holds the largest number of consecutive free blocks in the group as “max_free_block” in the second management table 28 (S202).

  Next, the file processing unit 24 determines whether the target block is not included in the largest number of consecutive free blocks in the group (S203, block specifying step). If the number of consecutive free blocks in the group is not included in the maximum number (YES in S203), the target block is read and encryption processing is performed on the RAM 26 (S204, data processing execution step).

The file processing section 24, the data amount of unwritten encryption processed in RAM26 is, determines whether the writable maximum size _{(S max)} than at a time _{(S205), S max} or If so (YES in S205), unwritten encrypted data is written to the disk 31 for _Smax (S206). Then, the process of step S203 is performed on the next block. On the other hand, if it is less than _Smax (NO in S205), the process of step S203 is performed on the next block as it is.

  On the other hand, when the number of consecutive free blocks in the group is included in the maximum in step S203 (YES in S203), the file processing unit 24 determines whether there is an unwritten block that has been encrypted in the RAM 26. If there is an unwritten block (YES in S208), the unwritten block is written to the disk 31 (S209). Then, the process of step S203 is performed on the next block.

  When the processing is completed up to the last block in the group (YES in S207), the file processing unit 24 determines whether there is an unwritten block that has been encrypted in the RAM 26 (S210), and there is an unwritten block. If this is the case (YES in S210), unwritten blocks are written to the disk 31 (S211). Then, the second encryption process is terminated.

  FIG. 7 is a diagram for explaining creation, updating, and encryption processing of the bitmap table 33 and the first management table 27 in the first encryption processing. As shown in FIG. 7A, the management table creation unit 25 refers to the bitmap table 33 to obtain free block information, and for each group, the first block number of a group of free blocks that are continuous from the end. A first management table 27 indicating the above is created in the RAM 26. In the example shown in FIG. 7A, the first block number of the group of empty blocks continuing from the end for Group 1 is “# 2”, “# N-1” for Group 2, and “#N” for Group 3. It has become.

  For example, when a new file is created in the #N block of Group 2, the free block number of Group 2 in the first management table 27 is set to “0 (none)” (FIG. 7B). This is because there is no empty block at the end of Group2.

  For example, when a file in the # N-1 block of Group 3 is deleted, the free block number of Group 3 in the first management table 27 is set to “# 2” (FIG. 7C). This is because the beginning of the group of empty blocks continuing from the end of Group 3 is the # 2 block.

  When the disk 31 is encrypted, the encryption is performed from the top block for each group. When the free block number block indicated in the first management table 27 is reached, the Group encryption processing is terminated (FIG. 7D). This process is repeated until all the groups are encrypted.

  FIG. 8 is a diagram for explaining creation, updating, and encryption processing of the bitmap table 33 and the second management table 28 in the second encryption processing. As shown in FIG. 8A, the management table creation unit 25 refers to the bitmap table 33 to obtain free block information, and for each group, the start block number and end block number of consecutive free blocks. Is created in the RAM 26.

  In the example shown in FIG. 8A, for Group1, the start block number of consecutive free blocks is “# 2” and the end block number is “#N”, and for Group2, “#N” -1 "and" #N ", and Group 3 indicates" # 2 "and" # N-2 ", and" #N "and" #N ".

  For example, when a new file is created in the # N-2 block of Group1, Group1 of the second management table 28 starts with the start block number “# 2” and the end block number “# N-3”. The block number is “# N−1” and the end block number is “#N” (FIG. 8B).

  For example, when a file in the # 1 block of Group 3 is deleted, the first Group 3 in the second management table 28 has the start block number “# 1” and the end block number “# N-2”. (FIG. 8 (c)).

  When the disk 31 is encrypted, the encryption is performed from the top block for each group. Then, the blocks included in the block having the largest number of consecutive empty blocks shown in the second management table 28 are not encrypted (FIG. 8D). This process is repeated until all the groups are encrypted.

  In the above-described embodiment, the first encryption process and the second encryption process are selected and executed. However, only one of them may be executed. That is, this embodiment is not limited to an apparatus that can execute both processes.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIGS. For convenience of explanation, members having the same functions as those described in the embodiment are given the same reference numerals, and descriptions thereof are omitted. In the above embodiment, the file processing unit 24 executes the encryption process. However, in the present embodiment, the file processing unit 24 executes the mirroring process. The flow when executing the mirroring process will be described. Here, it is assumed that the disk to be mirrored is disk A and the disk to be mirrored is disk B.

  As shown in FIG. 9, first, the bitmap table creation unit 21 creates a bitmap table 33 in the file system 32 by referring to the data 34 (S501). Thereafter, when there is a file creation (S502) or file deletion (S504) for the disk A (YES in S502 and S504), the bitmap table creation unit 21 updates the bitmap table 33 (S503).

  When the file processing unit 24 starts mirroring of the disk A (YES in S505), the bitmap table 33 of the group i (group i) is read (S506), and the free block number determination unit 22 refers to the bitmap table 33. It is then determined whether there are N or more empty blocks in the same group (S507). If the number of empty blocks in the same group is less than N (NO in S507), the process proceeds to “third mirroring process” in step S508.

  On the other hand, if there are N or more empty blocks in the same group (S507 YES), the block specifying unit 23 determines whether or not the size of the largest empty area (continuous empty block) in the group is F or more ( S509). If the size of the maximum free area in the group is F or larger (YES in S509), the process proceeds to “second mirroring process” in step S511. If the size of the largest free area in the group is less than F (NO in S509), the process proceeds to “first mirroring process” in step S510.

  Thereafter, the mirroring process is performed for all the groups, and when the mirroring process is completed for all the groups (NO in S512), the mirroring process is terminated.

Next, the flow of the first mirroring process will be described with reference to FIG. First, the management table creating unit 25 creates the first management table 27 of the group i (Group i) with reference to the bitmap table 33 (S601). Next, the block specifying unit 23 refers to the first management table 27 and determines whether or not the target block is the first block among empty blocks continuous from the end in the group (S602). If the first free block is not the first free block from the end (YES in S602), the file processing unit 24 reads the block and performs a mirroring process on the RAM 26 (S603). Then, the file processing unit 24 determines whether or not the amount of unwritten data that has been mirrored in the RAM 26 exceeds the maximum size (S _max ) that can be written at one time (S 604), and is less than S _max . If there is (NO in S604), the process of step S602 is performed on the next block. On the other hand, if it is equal to or greater than _Smax (YES in S604), unwritten mirrored data is written to disk B for _Smax (S605).

  In step S602, if the target block is the first of the free blocks continuous from the end (NO in step S602), the file processing unit 24 determines whether there is an unwritten block that has undergone mirroring processing in the RAM 26. If there is an unwritten block (YES in S606), the unwritten block is written to the disk B (S607). Then, the first mirroring process is terminated. If there is no unwritten block (NO in S606), the first mirroring process is terminated as it is.

  Next, the flow of the second mirroring process will be described with reference to FIG. First, the management table creation unit 25 creates the second management table 28 with reference to the bitmap table 33 (S701). Then, the management table creation unit 25 holds the largest number of consecutive free blocks in the group as “max_free_block” in the second management table 28 (S702).

  Next, the file processing unit 24 determines whether or not the target block is included in the largest number of consecutive free blocks in the group (S703). If the number of consecutive free blocks in the group is not included in the maximum number (YES in S703), the target block is read and mirroring processing is performed on the RAM 26 (S704).

Then, the file processor 24, the data amount unwritten in already mirroring process in RAM26 is, determines whether the writable maximum size _{(S max)} than at a time _{(S705), S max} or If there is (YES in S705), unwritten mirrored data is written to disk B for _Smax (S706). Then, the process of step S703 is performed on the next block. On the other hand, if it is less than _Smax (NO in S705), the process of step S703 is performed on the next block as it is.

  On the other hand, if it is determined in step S703 that the number of consecutive free blocks in the group is included in the maximum number (YES in S703), the file processing unit 24 determines whether there is an unwritten block that has undergone mirroring processing in the RAM 26. If there is an unwritten block (YES in S708), the unwritten block is written to the disk B (S709). Then, the process of step S703 is performed on the next block.

  When the processing is completed up to the last block in the group (YES in S707), the file processing unit 24 determines whether or not there is an unwritten block that has undergone mirroring processing in the RAM 26 (S710), and if there is an unwritten block. (YES in S710), the unwritten block is written to the disk B (S711). Then, the second mirroring process ends.

  The third mirroring process is a method in which the object of mirroring is only used blocks.

[Embodiment 3]
[Example of software implementation]
As Embodiment 3, an implementation example using software will be described. The control block of the information processing apparatus 1 (control unit (bitmap table creation unit 21, free block number determination unit 22, block identification unit 23, file processing unit 24, management table creation unit 25) 10) is an integrated circuit (IC chip). ) Or the like, or may be realized by software using a CPU (Central Processing Unit).

  In the latter case, the information processing apparatus 1 includes a CPU that executes instructions of a program that is software that implements each function, and a ROM (Read Only Memory) in which the program and various data are recorded so as to be readable by a computer (or CPU). Alternatively, a storage device (these are referred to as “recording media”), a RAM (Random Access Memory) that expands the program, and the like are provided. And the objective of this invention is achieved when a computer (or CPU) reads the said program from the said recording medium and runs it. As the recording medium, a “non-temporary tangible medium” such as a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like can be used. The program may be supplied to the computer via an arbitrary transmission medium (such as a communication network or a broadcast wave) that can transmit the program. The present invention can also be realized in the form of a data signal embedded in a carrier wave in which the program is embodied by electronic transmission.

[Summary]
A file system management apparatus according to an aspect 1 of the present invention is a block in which data is written among a plurality of the blocks in a file system management apparatus that manages a file system having a data structure managed for each block. A block specifying means for specifying a writing block and a part of an empty block that is a block to which data is not written, and at least one of reading and writing for all the blocks specified by the block specifying means Data processing execution means for executing common data processing.

  According to the above configuration, data processing including at least one of reading and writing is performed on all of the write block and the empty block specified by the block specifying means. Thereby, compared with the case where data processing is performed with respect to all the blocks, the amount of data processing can be reduced.

  Also, since some of the free blocks are also subject to data processing, the number of reads and writes for data processing can be reduced compared to the case where data processing is performed only on the write block. This is because when data processing is executed only for the write block, the number of reading and writing increases if there is an empty block between the write blocks.

  As described above, since the amount of data processing and the number of reading and writing operations can be reduced, the data processing can be made efficient and the processing time can be shortened.

  Examples of data processing include encryption processing and mirroring processing.

  The file system management apparatus according to aspect 2 of the present invention is the file system management apparatus according to aspect 1, wherein the file system has a data structure divided into a group including a plurality of the blocks, and the block specifying means includes the group for each group. The write block and a part of the empty block may be specified except for the empty block continuous from the end of the.

  According to the above configuration, in the group, blocks excluding empty blocks continuing from the end are targeted for data processing. As a result, the data processing amount can be reduced as compared with the case where data processing is executed for all blocks, and the number of reading and writing operations is reduced as compared with the case where data processing is executed only for writing blocks. Therefore, the data processing can be made efficient and the processing time can be shortened.

  In addition, since only the blocks excluding empty blocks continuous from the end are targeted for data processing, it is possible to specify the data processing target block with simple logic.

  The file system management apparatus according to aspect 3 of the present invention is the file system management apparatus according to aspect 1, wherein the file system has a data structure divided into a group including a plurality of the blocks, and the block specifying means is continuous for each group. The write block and a part of the empty block other than the empty block group having the maximum number of empty blocks may be specified.

  According to the above configuration, blocks other than the empty block group in which the number of consecutive empty blocks is the largest in the group are targets for data processing. As a result, the data processing amount can be reduced as compared with the case where data processing is executed for all blocks, and the number of reading and writing operations is reduced as compared with the case where data processing is executed only for writing blocks. Therefore, the data processing can be made efficient and the processing time can be shortened.

  The file system management device according to aspect 4 of the present invention is the file system management device according to any one of the above aspects 1 to 3, wherein the file system has a data structure divided into a group including a plurality of the blocks, and the number of free blocks included in the group The number of free blocks determining means for determining whether or not the number of free blocks included in the group exceeds the threshold, the block specifying means determines whether the number of free blocks included in the group exceeds the threshold. The block and a part of the empty block may be specified.

  When the number of blocks included in a group is small, it may be more efficient to perform data processing when only the write blocks included in the group are subjected to data processing. Therefore, if the number of free blocks included in the group is equal to or less than the threshold value, and if the data processing efficiency is improved by performing data processing only on the write block, the write block can be obtained by the above configuration. Only when data processing is more efficient when data processing is performed on some of the free blocks, it is possible to specify the write blocks and some of the free blocks and perform data processing.

  The file system management apparatus control method according to aspect 5 of the present invention is the file system management apparatus control method for managing a file system having a data structure managed for each block. A block identifying step that identifies a writing block that is a block that is being written and a part of an empty block that is a block to which no data has been written, and reading and writing to all of the blocks identified in the block identifying step A data processing execution step for executing common data processing including writing. Thereby, there exists an effect similar to the said aspect 1. FIG.

  The file system management apparatus according to each aspect of the present invention may be realized by a computer. In this case, the file system management apparatus is operated on each computer by causing the computer to operate as each unit included in the file system management apparatus. The control program of the file system management apparatus to be realized in this way and a computer-readable recording medium on which the control program is recorded also fall within the scope of the present invention.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

  The present invention can be used for an apparatus that executes data processing including at least one of reading and writing of data.

  DESCRIPTION OF SYMBOLS 1 Information processing apparatus (file system management apparatus), 10 Control part, 22 Free block number determination part (Free block number determination means), 23 Block specification part (Block specification means), 24 File processing part (Data processing execution means), 25 management table creation unit, 26 RAM, 27 first management table, 28 second management table, 31 disk, 32 file system, 33 bitmap table

Claims (5)

In a file system management apparatus that manages a file system having a data structure managed for each block,
A block specifying means for specifying a write block that is a block in which data is written and a part of an empty block that is a block in which no data is written, among the plurality of blocks;
A file system management device comprising: data processing execution means for executing common data processing including at least one of reading and writing for all of the blocks specified by the block specifying means . The file system is a data structure divided into a group including a plurality of the blocks,
2. The file according to claim 1, wherein the block specifying unit specifies, for each of the groups, the write block and a part of the free block excluding the free block continuous from the end of the group. System management device. The file system is a data structure divided into a group including a plurality of the blocks,
The said block specific | specification part specifies the said write block and a part of said empty block except the empty block group for which the number of continuous empty blocks becomes the largest for every said group. File system management device. The file system is a data structure divided into a group including a plurality of the blocks,
A free block number judging means for judging whether or not the number of free blocks included in the group exceeds a threshold;
The block specifying means specifies the write block and a part of the empty block when the empty block number determining means determines that the number of empty blocks included in the group exceeds a threshold. The file system management apparatus according to any one of 1 to 3.   A control program for causing a computer to function as the file system management apparatus according to any one of claims 1 to 4, wherein the control program causes the computer to function as each of the means.

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