JPH05314050A - Data transfer device - Google Patents

Abstract

PURPOSE:To directly transfer data without interposing any data stack part when the length of data to be transferred is the integral multiple of a block length as the minimum memory unit of an auxiliary storage device. CONSTITUTION:This device is provided with a command analysis part 1 to identify and output the write instruction of read instruction of data to auxiliary storage devices 6, 7, in instructions outputted from host devices, a data transfer method analysis part 2 to output the instruction for transferring data designated by the instruction outputted from the command analysis part 1 without interposing any data stack part 4 when the length of the data is the integral multiple (N) of the block length of the minimum memory unit of the auxiliary storage devices 6 and 7 and to output the write and read instructions of data while interposing the data stack part 4 in the other case. Corresponding to the data designated by the write or read instruction, a data transfer means 3 is controlled by a command outputted from the data transfer method analysis part 2 and when the data length of the data is equal to the integral multiple of the block length, the data are transferred without interposing the data stack part 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transfer device,
In particular, the present invention relates to a data transfer device that is interposed between a higher-level device such as an information processing device and an auxiliary storage device and is used to transfer data from one of the information processing device and the auxiliary storage device to the other.

[0002]

2. Description of the Related Art When a read command is applied to a data transfer device from a host device among operation commands from a host device to an auxiliary memory device, data is read from the auxiliary memory device and temporarily stored in a data stack section. After that, the transfer is performed in the order of the areas designated by the host device by the above-mentioned read command. When a write command is output from the host device, the data in the area designated by the host device is temporarily stored in the data stack unit and then transferred to the auxiliary storage device for writing. Data can be transferred in the minimum unit of data between the data stack unit and the area specified by the host device, but the transfer of data between the auxiliary storage device and the data stack unit is predetermined by the auxiliary storage device. Data is transferred at an integral multiple of the block length with the block length as the minimum unit. Since the data length requested by the host device is not always an integral multiple of the block length managed by the auxiliary storage device, when data transfer is performed directly between the auxiliary storage device and the area specified by the host program, data of the requested data length or more May be transferred to an area designated by a higher-level program, or unnecessary data may be written to the auxiliary storage device.

FIG. 3 is a block diagram showing an example of a conventional data transfer apparatus of this type, and FIG. 4 is a flow chart showing the operation of the apparatus shown in FIG. The conventional data transfer device shown in FIG. 3 has a command analysis unit 1 for identifying and outputting an instruction output by a higher-level device to the auxiliary storage device 6 or 7.
And a data transfer means 43 for transferring data between the auxiliary storage device and an area designated by the host device, and temporarily storing data output by the auxiliary storage devices 6 and 7 or a host device (not shown). In accordance with an instruction output from the data stack unit 4 and the data transfer means 43, writing of data to the auxiliary storage device 6 or 7 and auxiliary storage device 6 or 7
And an input / output control unit 5 for reading the data in the inside.

When there is a command for writing data to the auxiliary storage device 6 or 7 or a read command for reading data stored in the auxiliary storage device 6 or 7, the command analysis section 1 identifies the command content and issues this command. Is output to the data transfer unit 43 at step (hereinafter abbreviated as S) 51 shown in FIG.

The data transfer means 43 determines whether the received command is a write command or a read command (S5 in FIG. 4).
2).

When the host device issues a read command to be output to the auxiliary storage device 6 or 7, the read command specifies the auxiliary storage device to be read and the storage in the storage area of the specified auxiliary storage device. Includes the designation of the storage location (address) at which to start, and the data length of the data to be read from the designated auxiliary storage device, for example, the byte length. The designation of the storage device (either the auxiliary storage device 6 or 7 in the device of FIG. 3), the storage position (address) at which storage should be started, and the data length of the data to be stored are specified. ..

When the command judged by the data transfer means 43 is a read command, the data transfer means 43 extracts the data length contained in the command and stores this data length, that is, the number of blocks is N. Data length =
N, which is N · (block length), is calculated (S53). The data transfer means 43 designates one of the auxiliary storage devices 6 and 7 designated by the above-mentioned read instruction instead of the input read instruction, designates the number of blocks N instead of the above-mentioned data length, and also inputs. The read control command specifying the read start position in the specified auxiliary storage device specified by the read command is output to the input / output control unit 5. The input / output control unit 5 reads the data of the specified block number from the specified read start position in the auxiliary storage device specified by the read control command in the auxiliary storage device 6 or 7 and outputs it to the data transfer means 43. Yes (S5
4).

The data transfer means 43 temporarily stores the data output from the input / output control unit 5 in the data stack unit 4, and first reads out the data stored in the stack unit 4 by the input / output control unit 5. The data up to the data length specified by the read command from the host device in the data continuously read from the above data is output to the storage destination in the host device specified by the read command output from the above host device. (S55 and S56).

Further, in S52, when the data transfer means 43 determines that the input command is a write command, it temporarily receives the data to be written specified in the write command from the host device and It is stored in the stack unit 4.

The data transfer means 43 adds the necessary number of the above-mentioned 0 so that the data length in which the value 0 is added to the end of the data stored in the data stack unit 4 becomes an integral multiple of the above-mentioned block length ( S58), therefore, when the data length output from the higher-level device and stored in the data stack unit 4 is an integral multiple of the block length, 0 is not added.

Next, the data transfer means 43 designates and designates the auxiliary storage device (one of 6 or 7) designated by the write command output from the host device, by the data of the number of blocks described above. A block corresponding to the data length including the designation of the position of the storage start position in the auxiliary storage device described above, and the part to which 0 is added in the data stack unit 4 described above and the data stored before the addition of 0 as necessary. The write control signal specifying the number is output to the input / output control unit 5 (S5
9), output the data temporarily stored in the data stack unit 4, and write the input data to the auxiliary storage device (one of 6 or 7) designated by the input / output control unit 5 (S60). ..

[0012]

In the conventional data transfer apparatus, the same means is used regardless of the data length of the data to be processed regarding the write command or the read command to the auxiliary storage device output by the host device. Data is transferred between the storage area of the host device and the auxiliary storage device specified by the command. That is, regardless of whether or not the data length of the data to be transferred is an integral multiple of the block length which is the storage unit of the auxiliary storage device, all the data to be transferred is temporarily stored in the data stack section. Therefore, there is a drawback that the time required for data transfer becomes long.

In order to solve the above-mentioned drawbacks, the object of the present invention is to temporarily save data to the data tactic unit when the data to be transferred is an integral multiple of the block length managed by the auxiliary storage device. Another object of the present invention is to provide a data transfer device that can directly transfer data to an area designated by a host device and reduce the time required for data transfer processing.

[0014]

A command for writing data from the host device to the auxiliary storage device from among commands output from the host device and inserted between the host device and one or more auxiliary storage devices, and A command analysis unit that identifies the read command of the data stored in the auxiliary storage device and outputs the identified command, and the data that is subsequently added when the write control signal is received is stored in the storage location specified by the write control signal. From the specified storage area of the auxiliary storage device specified by the read control signal, the data in the area over the specified number of blocks is read In a data transfer device including an input / output control unit that controls output, output from the command analysis unit The data length contained in the received write command or read command is compared with an integral multiple of the block length of the auxiliary storage device, and if the data length is an integral multiple of the block length, the received instruction is When it is a write command, a direct write command including the designation of the auxiliary storage device included in the received write command, the write start position of the designated auxiliary storage device, and the number of blocks corresponding to the data length is output. When the received instruction is a read instruction, the designation of the auxiliary storage device included in the received read instruction, the designation of the read start position of the designated auxiliary storage device, and the number of blocks corresponding to the data length are included. And a direct read command including the above is output, and when the data length is not equal to an integral multiple of the block length, the received If the command is a write command, an indirect write command including the designation of the auxiliary storage device specified by the received write command, the write start position of the specified auxiliary storage device, and the data length is output, and the received command is the read command. , The data transfer method outputs an indirect read command including the designation of the auxiliary storage device designated by the received read command, the read start position in the designated auxiliary storage device, and the data length to be read. When the output of the analysis unit and the data transfer method analysis unit is used as an input and the direct write command is received, the received direct write command is transferred as a write control command to the input / output control unit, and is then output from the host device. When data is received, transferred to the input / output control unit and output, and the direct read command is received, this command is read When output as a control command to the input / output control unit, the read data output from the input / output control unit is output to a higher-level device, and when the indirect write command is received, it is transferred as the write control signal to the input / output control unit. Then, the data output from the host device is received, data having a value of 0 is added to the end of the data, and the data whose data length is an integral multiple of the block length is output to the input / output control unit as write data, When an indirect read command is received, this command is transferred and output as the read control command, and the read output from the input / output control unit is received to select only a specified data length portion and then output to the host device. And means.

[0015]

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

FIG. 1 is a block diagram showing an embodiment of the data transfer apparatus of the present invention, and FIG. 2 is a flow chart showing the operation of the data transfer apparatus shown in FIG.

As shown in FIG. 1, the data transfer apparatus of this embodiment includes a data write command and a data read command for the auxiliary storage devices 6 and 7 from various commands output from a host device (not shown). And a command analysis unit 1 for outputting these identified commands
Is the input and the data length that is the length of the data to be written or read included in the write command and the read command described above and the minimum data unit when the auxiliary storage devices 6 and 7 store. A data transfer method analysis unit 2 for checking the relationship with the block length and outputting an instruction corresponding to the result, and a storage area and an auxiliary storage in a host device (not shown) according to the instruction output by the data transfer method analysis unit 2. Data transfer between the device 6 or 7 and a data transfer unit 3 for outputting a write control command and a read control command for the data, and a write control command and a read command output from the data transfer unit 3. When either one of the control commands is received, the auxiliary memory device 6 or 7 designated by the received command is written with data according to the above command. Output control unit 5 to perform write or read, is connected to the data transfer means 3, and a data stack unit 4 for storing the output from the data transfer means 3 self addressed data.

When a write command or a read command is input to the data transfer method analysis unit 2, the relationship between the data length to be transferred included in this command and the block length described above is checked, and the block length is multiplied by an integer. When the target instruction is a write instruction, a direct write instruction is output, and when the target instruction is a read instruction, a direct read instruction is output and the data length and the block length are equal to each other. When the relation is not the above-mentioned relation, the indirect write instruction is output when the target instruction is the write instruction, and the indirect read instruction is output when the target instruction is the read instruction. In these instructions, the designation of the auxiliary storage device included in the instruction input from the higher-level device, the address in the storage area of this auxiliary storage device to start writing or reading, and the high-level device The address and the data length of the storage area in which the data of (1) is to be read or written are included.

The operation of the data transfer apparatus of the present invention shown in FIG. 1 will be described below with reference to FIG.

When a command for writing or reading data to or from the auxiliary storage device 6 or 7 is applied to the command analysis unit 1 from the host device, the command analysis unit 1 identifies these commands and outputs them to the data transfer method analysis unit 2. (S21).

First, the data transfer method analysis unit 2 determines whether the input write command is a write command or a read command (S22). If it is a read command, the relationship between the data length to be transferred specified in the input read command and the block length, which is the minimum unit of storage in the auxiliary storage devices 6 and 7, is checked, and an integer multiple of the block length ( It is determined whether or not (N times) is equal to the data length (S23).

When the data length is an integral multiple of the block length, a direct read command in which the data length designated by the input write command is changed to N, which is the number of blocks, is output to the data transfer means 3, When the data transfer unit 3 receives this command, it outputs a read control signal corresponding to the direct read command input to the input / output control unit 5, and the specified read of the auxiliary storage device specified by the above-mentioned upper device. From the start position, the data in the storage area over the designated block length is read and output to the data transfer means. The read data is received by the data transfer means 3, and this data is transferred to the storage area of the designated host device (S25).

In S23, if the data length to be transferred specified by the input write command is not an integral multiple of the block length, the data transfer method analysis unit 2 can include the specified data length. The indirect read command in which the number of blocks is added to the data length of the input write command is output to the data transfer unit 3 (S27). When the data transfer means 3 receives the indirect read command, the data transfer unit 3 reads the data over the block length specified by the indirect read command from the input / output control unit 5 from the specified read start address of the specified auxiliary storage device 6 or 7. Add a read control signal. The data read out by the input / output control unit 5 which has received the read control signal is once received by the data transfer means 3 and stored in the data stack unit 4.
The data of the data length included in the indirect read signal is extracted and corrected from the stored data (S29),
The data is sent to the address of the storage unit of the host device specified in the command (S30).

In step S22 described above, the data transfer method analysis unit 2
When the instruction input to is a write instruction, the data transfer method analysis unit 2 multiplies the block length by an integer multiple (N times) between the data length to be transferred specified in the instruction and the block length described above. ) Is checked to see if it is equal to the data length (S24). An integer multiple of the block length (N
When the input write command is equal to the number of blocks, the data length of the input write command is changed to N, which is the number of blocks, and a direct write command is output to the data transfer unit 3. A write control signal specifying the designation of the auxiliary storage device specified in the designated and input instruction and the address indicating the write start position of the auxiliary storage device is applied to the input / output control unit 5, and then the input instruction is executed. Data is transferred to the input / output control unit 5 from the specified address in the storage unit of the specified host device, and the auxiliary storage device (either 6 or 7) specified by the input / output control unit 5 is specified. It is stored in the storage location (S26).

When the data length is not an integral multiple of the block length in S24 described above, the data transfer method analysis unit 2
In addition to the data length specified by the input write command, an indirect write command that specifies the number of blocks that can include this data length is added to the data transfer means 3, and the host device specified by the data transfer means 3 The data in the storage area is temporarily stored in the data stack unit 4 (S31).

Next, the data transfer means 3 adds 0 to the end of the data stored in the data stack unit 4 until the data length becomes an integral multiple of the block length (S32).

Next, the data transfer means 3 outputs a write control signal designating the number of blocks to be equal to the data length of the data added with 0 to the input / output control section 5 (S33), The data with 0 added to the end stored in the data stack unit 4 is output to the input / output control unit 5, and the data is transferred to the specified address of the auxiliary storage device specified by the write command output from the host device. Means 3
The data output from is written (S34).

As is apparent from the above description, when the data length of the data to be transferred is equal to an integral multiple of the block length, the data is transferred without being temporarily stored in the data stack section. become.

In the above description, the auxiliary storage devices 6 and 7 are connected to the data transfer device of the present invention, but the input / output control unit 5 is connected to at least one auxiliary storage device. Obviously, any number of units can be used.

[0030]

As described above, in the data transfer device of the present invention, the data length included in the write command or the read command output from the host device by the data transfer method analysis unit 2 is stored in the auxiliary storage device. It is judged whether it is equal to an integral multiple of the block length which is the minimum unit, and when the data length specified by the instruction is equal to an integral multiple of the block length,
Since data is transferred between the auxiliary storage device and the higher-level device without storing the data to be transferred in the data stack unit, as compared with the conventional data transfer device of this type,
This has the effect of reducing the time required to transfer data.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a data transfer device of the present invention.

2 is a flowchart showing an operation of the data transfer device shown in FIG.

FIG. 3 is a block diagram showing an example of a conventional data transfer device of this type.

FIG. 4 is a flowchart showing an operation of the data transfer device shown in FIG.

[Explanation of symbols]

 1 command analysis unit 2 data transfer method analysis unit 3 data transfer means 4 data stack unit 5 input / output control unit

Claims (1)

[Claims] 1. An instruction to write data from a higher-level device to the auxiliary storage device in the command output from the higher-level device inserted between the higher-level device and one or more auxiliary storage devices and the auxiliary storage device. A command analysis unit that identifies the read command of the stored data and outputs the identified command, and the data that is subsequently added when the write control signal is received is specified from the storage position specified by the write control signal. When a write control and a read control signal are received up to the storage area of the number of blocks, a control of reading and outputting the data of the area for the specified number of blocks from the specified storage area of the auxiliary storage device specified by the read control signal is performed. In a data transfer device having an input / output control unit for performing, the output from the command analysis unit is received and the received data is written. The data length included in the write command or the read command is compared with an integer multiple of the block length of the auxiliary storage device, and if the data length is an integer multiple of the block length, the received command is a write command. In some cases, a direct write command including the designation of the auxiliary storage device included in the received write command, the write start position of the designated auxiliary storage device, and the number of blocks corresponding to the data length is output and received. When the command is a read command, a direct read including the designation of the auxiliary storage device included in the received read command, the designation of the read start position of the designated auxiliary storage device, and the number of blocks corresponding to the data length. When the command is output and the data length is not equal to an integral multiple of the block length, the received command is the write command. If so, an indirect write command including the designation of the auxiliary storage device specified by the received write command, the write start position of the specified auxiliary storage device, and the data length is output, and when the received command is a read command, the indirect write command is output. A data transfer method analysis unit for outputting an indirect read command including designation of the auxiliary storage device designated by the received read command, a read start position in the designated auxiliary storage device, and a data length to be read; When the output of the transfer method analysis unit is input and the direct write command is received, the received direct write command is transferred and output as the write control command to the input / output control unit, and subsequently the data output from the host device is received. When the direct output command is transferred to the entry output control unit and the direct read command is received, this command is used as the read control command. When the read data output to the writing output control unit and output from the input / output control unit is output to the host device and the indirect write command is received, the read data is transferred to the input / output control unit as the write control signal and output from the host device. The output data is received, data having a value of 0 is added to the end of the data, and data having a data length that is an integral multiple of the block length is output to the input / output control unit as write data and the indirect read command is output. When receiving, this command is transferred and output as the read control command, and the read output from the input / output control unit is received, and only the designated data length portion is selected and then output to the upper device. A data transfer device characterized.