JPS61278957A - I/o transfer data trap system - Google Patents

Abstract

PURPOSE:To collect access request source source information by checking whether or not the trap definition area of a main memory device is accessed at the time of analyzing a channel command word CCW. CONSTITUTION:When data is transferred to an I/O device 4, a channel device 3 executes the CCW analysis, and a control part 9 checks whether the trap definition is present or not with the aid of trap difinition presence or absence information on contents in a register 5. When the trap definition is present, it is checked to be an access to the trap indication area or not with the aid of the main memory address of a CCW memory 8, the number of transfer words, the trap definition area top addresses of the contents of registers 6 and 7 and a trap definition final address. When it is the access to the trap definition area, a trap detecting flag 10 is set, and a trap interruption is applied to a central processing unit 1. Thus the central processing unit 1 can collect the address of the I/O device issuing an access request and trap information on CCW, etc.

Description

[Detailed Description of the Invention] [Summary] It is detected whether or not a trap designated area on the main storage device has been accessed by data transfer with the input/output device, and a trap interrupt is sent to the central processing unit. This makes it possible to investigate the cause of illegal access to a specific area on a storage device.

[Industrial application field]

The present invention provides a central processing unit, a main storage device, a channel device,
The present invention relates to an input/output transfer data trap method for trapping main memory accesses due to data transfer between input/output devices in systems equipped with input/output devices.

[Conventional technology]

The trap specification area of the main memory is specified by a command, and when the central processing unit accesses the main memory,
Since it is possible to determine whether or not the area is a trap designated area based on the access address, when the trap designated area is accessed, a trap interrupt is issued to the central processing unit itself. This trap interrupt collects information such as the source of the access request and investigates the cause of access to the trap designated area.

[Problem that the invention seeks to solve]

When the main memory is accessed from the central processing unit, a trap interrupt can be performed as described above, but when the trap specified area of the main memory is accessed during data transfer with the input/output device, The central processing unit cannot determine whether the access is to a trap designated area or not. Therefore, in this case, a trap interrupt cannot be performed, and when an area of the main memory is illegally accessed by an input/output device, it is difficult to investigate the cause.

The present invention aims to detect whether or not a trap designated area on a main storage device is accessed through data transfer with an input/output device, and if it is detected, to collect information on the source of the access request. It is something.

[Means for solving problems]

The input/output transfer data trap method of the present invention will be explained with reference to FIG. When the trap designation area of the device 2 is designated by a command and the main storage device 2 is accessed during data transfer of the input/output device 4, the information of the input/output control program or the trap designation area is transferred to the channel device 3 in advance. When the channel command word (CCW) is analyzed, it is checked whether the access is to the trap specified area, and if the access is to the trap specified area,
It makes a trap interrupt to the central processing unit 1 and collects access request source information including input/output device addresses and the like.

[Effect]

During data transfer with the input/output device 4, the input/output control program or the channel device 3 checks whether or not the trap designated area of the main storage device 2 has been accessed when the channel cloak word (CCV) is analyzed. Similar to the access from the device 1 to the main storage device 2, the access from the input/output device 4 can also be trapped.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a block diagram of an embodiment of the present invention, in which 1 is a central processing unit, 2 is a main storage device, 3 is a channel device, and 4 is a block diagram of an embodiment of the present invention.
5 is an input/output device; 5 is a register for setting trap designation identification information; 6 is a register for setting a trap designation area start address; 7 is a register for setting a trap designation area final address; 8 is a channel command word memory; 9 is a control unit, and 10 is a trap detection flag.

The central processing unit 1 sets the trap designation area of the main storage device 2 by a command, and the trap designation identification information, the trap designation area start address, and the trap designation area end address are sent to the registers 5.6 of the channel device 3 by a special command. ．． 'Set to 7.

During data transfer with the input/output device 4, the channel device 3
The channel command word is analyzed, and the controller 9 checks whether there is a trap designation based on the trap designation identification information contained in the register 5. If there is a trap designation, access to the trap designation area is based on the main memory address and transfer word count of channel command word memory 8, and the trap designation area start address and trap designation end address of the contents of register 6.7. Check whether or not.

When accessing a trap designated area, a trap detection flag 10 is set and a trap interrupt is issued to the central processing unit 1. Thereby, the central processing unit 1 collects trap information such as the address of the input/output device 4 of the access request and the channel command word. Therefore, when data is transferred between the input/output device 4 and the main storage device 2 by DMA transfer, access to the trap designated area of the main storage device 2 can be trapped.

FIG. 3 is an explanatory diagram of another embodiment of the present invention, in which processing is performed by an input/output control program. When starting up the input/output device, edit the channel command word CCW (1
), )Check whether there is a wrap specification (2).

If there is no trap specification, the input/output device is started (3) as normal processing.

In addition, if there is a trap specification, analysis of the channel command word CCW such as main memory address specification and transfer word count specification (
4) and compares the access area with the trap designated area information based on the trap designated area first address and trap designated area final address (5). Thereby, it is determined whether the access is to the trap designated area (6), and if the access is not to the trap designated area, the input/output device is activated (3). In addition, in the case of access to a trap designated area, trap information such as input device address, channel command word CCW, access request (information on whether to write data or continue), etc. is collected (7), and the trap information is stored in one layer. do. The contents of this trap information collection area can be displayed by a command.

In addition, in the main memory device 2 consisting of a storage section and a control section, the control section is provided with registers, etc. for storing trap designation identification information and trap designation area information, similar to the channel device 3 of FIG. When a DMA (direct memory access) request is received from the input/output device 4, the control unit identifies the presence or absence of a trap specification based on the trap specification presence/absence identification information, and if there is a trap specification, the main memory address of the access request is the trap specification. It is checked whether the area belongs to the specified area range, and if the access is to the trap specified area, a trap detection signal is sent to the channel device 3, and the channel device 3 uses the trap detection signal to detect the trap detected channel. identify the command word CCW;
At the end of the execution of the channel command word CCW, an interrupt is made to the central processing unit 1 which has added the presence or absence of trap detection to the interrupt information.

The central processing unit 1 collects trap information such as input/output device addresses and channel command words CCW based on information indicating that a trap has been detected in the interrupt information.

〔Effect of the invention〕

As explained above, according to the present invention, when accessing the main storage device 2 from the input/output device 4 by DMA or the like, the channel command word CCW determines whether or not the access is to the trap designated area of the main storage device 2. It is possible to identify the information by editing, analyzing, etc., issue a trap interrupt to the central processing unit 1, and collect trap information for investigating the cause of the illegal access from the input/output device 4.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the principle of the invention, FIG. 2 is a block diagram of one embodiment of the invention, and FIG. 3 is an explanatory diagram of another embodiment of the invention. 1 is the central processing unit, 2 is the main memory, 3 is the channel device, 4 is the input/output device, 5.6.7 is the register, 8 is the channel command word memory, 9 is the control unit, and 10 is the trap detection flag. be.

Claims (1)

[Scope of Claims] In a system comprising a central processing unit (1), a main memory (2), and an input/output device (4) controlled via a channel device (3), the main memory comprises: The trap designation area of the device (2) is designated by a command, and the input/output control program or the information of the trap designation area is pre-programmed for access from the input/output device (4) to the main storage device (2). When analyzing the channel command word in the transferred channel device (3),
Checks whether or not the access is to a trap designated area. If the access is to a trap designated area, a trap interrupt is made to the central processing unit (1), and access request source information including input/output device addresses, etc. An input/output transfer data trap method characterized by collecting .