JPS5999564A - Protection system against writing to disk - Google Patents

Abstract

PURPOSE:To perform write protection by loading the object projection range of a disk file shared by plural computers and a write inhibition level for specifying write inhibition with a double sign system level in a read/write memory. CONSTITUTION:When one of CPUs 1001-100m generates a write request to a disk file 300, access information is transmitted to a control part 201 through an adapter 205. The access information consists of an access CPU number, access request object address, write information, etc., and write protection information consisting of an object starting address of write inhibition, object final address of write inhibition, and write inhibition level is loaded; and the control part 201 decides on whether the access information is within the inhibition object range of an RAM 203 or not and decides on an inhibition level which allows unconditional writing when not, thereby performing writing operation. When the access information is within the range, write control is carried out according to the activity state information of the CPU.

Description

[Detailed description of the invention]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a complex computer system that performs multiple calculations (
The present invention relates to a disk four-inclusion protection method that protects disk files shared by users. [Technical Background of the Invention and Intermediate Points] Generally, in an information processing system, physical write protection to the memo IJ ff ['i Makoto] is required. FIG. 1 shows a system in which physical protection (prohibition/permission) of p1 to a disk file is performed, and 10 is a CPU. 0
A disk access request, such as a write request, from the PU 1o can be sent to the disk access control device 20. Disk access? The 1jlla device 20 receives access requests from the 0PUIO and controls access to the disk file 3Q, and includes a control section 2, a disk drive section 22, and an interpolation prohibition/permission switch 23. The write prohibition/permission switch 23 is a pinboard switch, a toggle switch, or the like, and by operating these switches, it is possible to specify write prohibition/permission for the entire disk or a portion thereof. In such a system, when a write request is issued from 0PUlo to the disk access control device 20, the control unit 21 reads the state of the write prohibition/permission switch 23. Then, the control unit 21 determines whether the address corresponding to the write request issued by OP and Ulo is write-prohibited. If access is prohibited, the control unit 21
does not perform writing, but if writing is permitted, it accepts the request and outputs a write drive request to the disk drive unit 22. Such operation of control IMI<27 guarantees write protection to the disk file 30 at a physical level. According to this protection function, when a system consists of a single system or two or more 01'Us, and those OPUs share the same disk, each OP'U has exactly the same disk write-protected area. Sometimes, monetary protection at the physical level is guaranteed. However, in a system such as a complex computer system, such as a duplex computer system, where the main system performs the main work and the slave system (standby system) performs thick-ground work, Since write protection for disk files is essentially disk-level protection in J19, there are the following problems. In other words, in this scale system, there is a possibility that a disk area that should be accessed by the main system may be mistakenly rewritten by a disk access from the standby system. Embedded protection is not guaranteed. [Object of the Invention] The present invention has been made in consideration of the above circumstances, and its purpose is to provide a disk write protection hardware that can guarantee physical write protection to disk files that are shared in a complex computer system. The method is to: /I'i: Load protection information for a specific computer in a complex computer system to the read/write memory at the time of system initialization. As this write protection information, in addition to the write protection target range of the disk file, there is also a +1'4- write protection level that specifies write protection at the complex system level. In the invention, upon a write request from a total of Q8 machines, Y4 write protection to the disk file is performed based on the write protection information in the read/occupied memory and the operating status of each computer that makes up the composite extra r-case system. i:
IlJ go! 1ilJ? By providing the iIj section, physical annotation protection for disk files in the system is guaranteed for the complex calculation system 1. Further, in the present invention, the write protection information in the read/write memory can be changed/deleted by external operation means, thereby facilitating maintenance and the like. [Example of the Invention] Hereinafter, one embodiment of the present invention will be explained with reference to the drawings at -11, H and L9. Figure 2 shows a complex system R to which the present invention is applied.
1-It shows the configuration of a computer system, 100. . 100 tv ・” 100 rn U OL' U
It is. CPU100 is, for example, the main CPU%0PU
100° to 100m is a subordinate QPU. 20 (lambda disk access control device. Disk access control device V1.200 is a control unit 20) and a disk 1 disk access control device.
11 parts 202 and RA'M (Random Access Memory, Read/Write Memo IJ) 2 U,'
j, an input/output unit 204 as an external operation means, and a cross call adapter (hereinafter referred to as an attachment to IA5.
) 205. 300ge disk file, 4001.400. ,...400m is the corresponding 0P
UI 00. , l 00. ,・-10()m
Control the operating status information indicating the operating status of (+114gtS2
This is a signal line for transmitting to 0 l. In such a configuration, disk access fli! Control everyone! T200 is initialized at system initialization. At this time, from 0PUlθ01 on the main system side, the disk f
The sales protection information that is necessary for Y-inclusive protection is transferred to the disk access control device 200,

[ is also loaded into AM203.几kM203 has 5 as shown in Figure 3.
LOTJ~S LOT n (7) n slots are prepared, and the corresponding slot) S LOT i has one write-protected start address S A D Ri, a write-protected last address n A D It i, and (1 yen). 1' consisting of P L B V L i)
The included insurance information will be loaded. Upper 7th self S8]) Ri
p EA DRi is written in the disk file 300 (
This indicates the start address and the end address, respectively, of a write-prohibited address area (consecutive addresses) - a write-prohibited address area. The above PLEVLi is used to designate write prohibition at the composite system level, and has four levels from level O to level 300. In this example, level 0 is either the main or subordinate OL)
It also prohibits the provision of food from the United States. Furthermore, level 1 prohibits only writing from the system CPU, and level 2 prohibits only writing from the main system CPU. Furthermore, level 3 indicates that access from the OPUs of both the main system and the slave system tb is also permitted. The human output unit 204 is an operation unit for manually controlling the control unit 201, and has a control mode (normal mode/maintenance mode) setting function and lthM203 in the maintenance mode.
The best way to change the content of 1. 4th 几AM 2 o
It includes a switch and a display (none of which are shown) for realizing the function of displaying and outputting the contents of 3. In the normal mode 7ii, 14, the normal mode is selected by a predetermined switch of the input/output section 204. The operation in this normal mode will be explained in detail below. OP
Any CPU from U 1001 to 100 m is a disk file? When a write request to 00 is issued, the write request is further transmitted to the adapter 205. adapter 2
05 phantom: It has the well-known function of switching and synchronizing disk access requests from 0PU 100° to 100m, and the 22nd access OPU number, access request target address (target address including 114), and f
11-inclusive data as basic information is output as control ll2o1&. When the control unit 201 receives the access 1ff information, it searches the RAM 303 and determines whether the current address to be written is included in any of the write-prohibited ranges indicated by the import protection information of each slot. In this judgment, the address to be written this time is FLA.
If it is not included in any of the write-prohibited ranges indicated by each slot in M203, the control unit 20 determines that the write-prohibit level is 3. This level 3 indicates that it is unconditionally writable regardless of whether it is a master system or a slave system (standby system). Then, the control unit 201 issues a busy drive request to the disk drive unit 202. As a result, disk file 900 is accessed,
Data is loaded into the designated area of the file 300)11'. On the other hand, if it is determined that the target address is included in any tL of the target range for prohibiting Z1 inclusion indicated by the write protection information of each slot in RA)J203, the control unit 201 is the corresponding slot) SLOTi write inhibit level PLEVL i and signal lines 400, ~4
0PUlo transmitted via 00m, o□~100
The following judgment is made with reference to the operating state information of m. The operating state information indicates whether the OPU in question is normal or not, and if the CPU in question is normal, it indicates whether the CPU is in the main system or the slave system (standby system). ■ When all IJ P U (J o o, ~100m) are normal (at write-in prohibition level 0, intrusion is not possible. (bl 〒i1 write-in prohibition level 1 and i + - ~100m), each ingress is not possible. i) "i, ingress is allowed, and if there are multiple CPU0PUs in the main system, the OPU that issued the request first is given priority,
Subsequent OPUs are treated as standby CPUs. Therefore, the OP U i, J of the f thread string: After the writing from the preceding CPU is completed, the 1st-age O'C soldier is given permission to write. tdl 'If the write prohibition level is 3, the write request source is the main CPU (1c+c+,), the slave OP U
(100t to 100rn') Writable in either case. waits 0 (even if the request is issued before the main CPU)
1) Treated as U. ■ One main CPU (100,) and one slave CPU, for example 1, 0 PIJloo; + when normal)
If the 'j'F inclusion prohibition level is 0, 1 yen and N are not allowed. (If the write protection level is l, ■1) When the request source is the main CPU (lc+c+,), it is writable, and the slave CPU (1oo, ~1 o o rn
), writing is disabled. (cl ¥”F If the write prohibition level is 2, v1 write is allowed only when the write request source is a normal slave system 0PUC100t). bIl 4・) - If the write prohibition level is 3, the write request source is the master system It is possible to insert only when the main system is 0PU (1c+c+1) or the normal slave CPU (1c+c+,). However, the main system (1!PU(1c+c+,), the normal slave system 0p
If there is a request from both U (100,), the main CP
U (1oO8) is installed first, and the normal subordinate CPU (lO
c+, ) is treated as a standby CPU. ■ When only the main CPU (1c+c+1) is normal (
a) F-: If the write prohibition level is O, writing is prohibited. (1)) Write protection level 1, 2, , ? (1) The source of the included request is the main CPU (JO
Writing is possible only when (71). ■ When only the main system 0PU (100,) is abnormal (a),
υ) If the write protection level is 0, writing is unnecessary. (hl 'f!T If the level of prohibition including T is 1 or 2.3, then ge) The request source is the slave CPU (1oo2~
Writing is possible only when the value is 1oom). Note that in this case, the content of proviso v) of item (1)C) above applies. ■ One of the slave CPUs, for example OPU'lOo. If only fat ν4 is normal and the 5g limit level is O, then 6" is not allowed. 0PU(100□
) P1'' can be included only when
o. When only c' is abnormal, basically the same as ([↓ and 0PUIUO. (When only 72 is abnormal, it is basically the same as in ■ above, and writing is always disabled for 0PU1oo. Based on the above judgment, 1e, which has become the best time to write, is 1i
The lJ saving part 201 is located in the disc handle part 202Q
) Issues an inclusion request. This will cause disk file 30
A write to 0 is performed. On the other hand, non-writable glue 4
In this case, the control unit 201 simply notifies the Y1 loading request source OPU of this fact via the adapter 205, and therefore the loading 1611 operation is not performed. In addition, 1i1. If the write target address (occupation target area) extends over two or more ranges of write-prohibited ranges indicated by each slot in ItAM 203 For example, it is preferable to adopt the method of decreasing the level number. Next, we will explain the masterpiece in maintenance mode. In maintenance mode, when testing the system, etc., IL A
It is necessary to change the write protection information of any slot 8T, OTi in Ni 203 to -lJi J,,I
, this is a mode that makes this possible (not possible in the normal mode mentioned above). Switching from the normal mode to the maintenance mode is possible by operating a predetermined switch of the input/output unit 204. The write protection information in It AM 203 is changed/deleted as follows. (A) The author turns on the input/output section 204. Specify the address to which writing is prohibited (or permitted). (b) Control unit 201 i'J: In the maintenance mode, if the target address is prohibited (or permitted) from input/output unit 204, the address is prohibited from writing as indicated by 11) write protection information in RAM 203. It is determined whether or not it is included in any of the target axis times, and this fact is displayed on the display of the input/output unit 204. (c) The control unit 201 stores the write protection information of the corresponding slot for islands where the above address is included in any of the 111 target ranges. Read everything from AM2os and display it on the display. b) If necessary, the operator operates a switch on the input/output section 204 to instruct the control section 201 to change or delete the write protection information of the corresponding slot, if necessary depending on the content displayed on the display. This allows the control unit 201 (11.AM, 203 to be accessed and the content of the slot to be deleted or designated.
Change your focus to information. (E) On the other hand, if the above address is not included in any of the write target ranges, the operator operates a switch on the input/output unit 204 to add write protection information if necessary. In this way RAM, ) in c+3? F-included insurance information is changed, deleted, or added. ν) Write protection i performed by referring to the write protection information in this RAM 203
For it+ work, normal mode glue 3 and 4. :If
Therefore, the explanation will be omitted. Note that in the ni+ embodiment, the write protection information is
Although the explanation has been made assuming that the information is transferred from U and loaded into R and AM, the slave system 01) U may transfer the write hold information to the RAM concerned. In the above embodiment, when both the main OPU and the slave CPU are writable, writing from the main OPU always has the highest priority, but the following may also be used. . That is, the fiHI unit 201 determines whether or not the write target addresses from multiple 〒1+ write request sources are the same. If they are the same, priority is given to writing from the main OPU. On the other hand, if they are different, the main CPU is treated equally as the slave OPU. In this case, write permission aJ f
:J, given in order from the OPU that first issued the VCC fetch request. 〔Effect of the invention〕 . Hereinafter, J: i+1: As described above, according to the present invention, the following effects can be achieved. ■ Flexible disk file write protection can be performed in complex computer systems. ■ Exclusive control 1 of file writing between computers at the physical level in a complex computer system can be performed. ■ The protection information stored in M (read/write memory) to R is the 01) U of the removal and removal inserts υ that make up the system.
(computer) is transferred to the RAM by the software.For example, even if a bailiff occurs on the disk due to file organization, it will not be possible to perform field work. ■ It is possible to deal with it quickly. ■ During maintenance, etc., it is necessary to
+'s protection, write protection level can be arbitrarily changed, deleted,
Can be added. Therefore, system tests, etc. can be carried out efficiently without affecting the system.

[Brief explanation of the drawing]

FIG. 1 is a block diagram illustrating a general information processing system, and FIG. 2 is a block diagram illustrating an embodiment of a complex system to which the present invention is applied. , FIG. 3 is a diagram showing the memory map of the AM in the above embodiment. 1001 to 100m...CPU (computer), 2θ0.
...Disk access control device, 201...1 interval? 1
111 part, 203... RAM (read/write memory), 204... input/output section, 300... disk file, 400. A-400m...Signal line. Applicant's agent Patent attorney Takehiko Suzue Figure 1

Claims (2)

[Claims] (1) A read/write memory that can be read and written in a complex computing system in which multiple computers share a disk file. At the time of system initialization, the write protection information with the write protection level that specifies the write protection period of the disk file and the write protection at the complex system level is read from a specific bulletin machine among the plurality of computers mentioned above. means for loading the difference protection information in the read/write memory; external operation means for changing/deleting the difference protection information in the read/write memory; and an external operation means for changing/deleting the difference protection information in the read/write memory; An f171J control unit that controls f4° write protection to the disk file based on write protection information and the operating status of each of the plurality of computers. (2) The disk, imp, etc. according to claim 1, wherein the specific computer is a main computer
Built-in protection method.