System for locating a file in a logical ring by sequentially forwarding access request with file system name and file name

• US 5,014,192 A
• Filed: 01/19/1989
• Issued: 05/07/1991
• Est. Priority Date: 05/06/1985
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola Computer X Inc (Motorola Solutions, Inc.)
• Inventors: Kun, Andrew I., Mansfield, Bruce M., Kolnick, Frank C.
• Primary Examiner(s): Lee, Thomas C.
• Application Number:
  US07/300,687
• Time in Patent Office: 838 Days
• Field of Search: 364/200 MS File, 364/900 MS File, 340/825.05, 340/825.50, 370/85.4, 370/85.5, 370/94.1
• US Class Current: 1/1
• CPC Class Codes: G06F 15/17337 Direct connection machines, e.g. completely connected computers, point to point communication networks coupling between buses G06F13/4004
• CPC Class Codes: G06F 16/148 File search processing
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99939 Privileged access

Abstract

A data management system used by a digital computer system comprises a plurality of individual file systems which are connected together in a logical ring configuration around which file requests travel. File requests may be transmitted by the user to the "next" file system in the ring relative to the user.

File requests optionally may or may not specify a file system name. If a file system name is specified, then the request is forwarded unidirectionally around the logical ring until either that file system name is found or the request returns to its starting point. If no file system name is specified, then an attempt is made to satisfy the request on each file system in turn until either the request is satisfied or the request returns to its starting point.

Claims

1. A method of providing file system access in a data management system used in a data processing system comprising at least one processor, at least one memory storage unit coupled to said at least one processor, and a plurality of individual file systems and a requesting process contained in said at least one memory storage unit, said method comprising the steps of:

(a) generating an access request by said requesting process for a file having a given file name in one of said file systems having a given file system name, said access request specifying said file name and said file system name;

(b) transmitting said access request to one of said file systems;

(c) determining whether said file system has said specified file system name, and, if so, proceeding with step (e), but if not, automatically forwarding said access request to a different file system;

(d) repeating step (c) until either said file system with said specified file system name is located, in which case proceeding with step (e), or until said access request has been received by all of said file systems without locating said file system with said specified file system name and in such case generating an indication of an unsuccessful access to said file to said requesting process; and

(e) determining whether said access request can be satisfied by said file system with said specified file system name, and, if so, satisfying said access request and generating an indication thereof directly to said requesting process, but if not, generating an indication of an unsuccessful access to said file to said requesting process.

2. The method of providing file system access recited in claim 1, wherein in steps (b) and (c) said access request is always forwarded to said file systems in a predetermined order.

3. A method of providing file system access in a data management system used in a data processing system comprising a plurality of processors interconnected by a network, a plurality of memory storage units, each processor being coupled to at least one memory storage unit, and a plurality of individual file systems and a requesting process contained in at least one memory storage unit, said method comprising the steps of:

(a) generating an access request by said requesting process for a file having a given file name in one of said file systems having a given file system name, said access request specifying said file name and said file system name;

(b) transmitting said access request to one of said file systems;

(c) determining whether said file system has said specified file system name, and, if so, proceeding with step (e), but if not, automatically forwarding said access request to a different file system;

(d) repeating step (c) until either said file system with said specified file system name is located, in which case proceeding with step (e), or until said access request has been received by all of said file systems without locating said file system with said specified file system name and in such case generating an indication of an unsuccessful access to said file to said requesting process; and

(e) determining whether said access request can be satisfied by said file system with said specified file system name, and, if so, satisfying said access request and generating an indication thereof directly to said requesting process, but if not, generating an indication of an unsuccessful access to said file to said requesting process.

4. The method of providing file system access recited in claim 3, wherein in steps (b) and (c) said access request is forward to said file systems in a predetermined order.

5. A data management system for use in a data processing system comprising:

at least one processor for executing instructions;

at least one memory storage unit coupled to said at least one processor, said memory storage unit storing instructions and data;

a plurality of individual file systems contained in said at least one memory storage unit;

means responsive to the execution of an instruction by said at least one processor for generating an access request for a file having a given file name in at least one of said file systems having a specified file system name, said access request specifying said file name and said file system name;

means responsive to said access request generating means for transmitting said access request to one of said file systems;

first means responsive to the receipt of said access request for determining whether said one file system has said specified file system name, and, if so, generating a first control signal, but if not, generating a second control signal;

second means responsive to said first control signal for determining whether said access request can be satisfied by said file system having said specified file system name, and, if so, for satisfying said access request and generating a first indication of a successful access to said file directly to said at least one processor, and, if not, for generating a second indication of an unsuccessful access to said file;

third means responsive to said access request generating means, to said second control signal, and to said second indication for automatically forwarding said access request to successive, different file systems whereby;

(a) if said access request is forwarded to a file system having said specified file system name, said first control signal is generated by said first means, in which case said second means either generates said first indication or said second indication, depending upon whether said file is successfully or unsuccessfully accessed, respectively, and

(b) if said access request is forwarded to a file system not having said specified file system name, said first means generates said second control signal,

said third means ceasing to forward said access request after all of said file systems have been unsuccessful accessed and generating a third indication of an unsuccessfully access to said file directly to said at least one processor.

6. The data management system recited in claim 5, and further comprising means responsive to said access request generating means and to said access request forwarding means for forwarding said access request to said file systems in a predetermined pattern.

7. A data management system for use in a data processing system comprising:

a plurality of processors for executing instructions, said processors being interconnected by a network;

a plurality of memory storage units, each said processor being coupled to at least one of said memory storage units, said memory storage units storing instructions and data;

a plurality of individual file systems contained in at least one of said memory storage units;

means responsive to the execution of an instruction by one of said processors for generating an access request for a file having a given file name in at least one of said file systems having a specified file system name, said access request specifying said file name and said file system name;

means responsive to said access request generating means for transmitting said access request to one of said file systems;

first means responsive to the receipt of said access request for determining whether said one file system has said specified file system name, and, if so, generating a first control signal, but if not, generating a second control signal;

second means responsive to said first control signal for determining whether said access request can be satisfied by said file system having said specified file system name, and, if so, for satisfying said access request and generating a first indication of a successful access to said file directly to said one of said processors, and, if not, for generating a second indication of an unsuccessful access to said file;

third means responsive to said access request generating means, to said second control signal, and to said second indication for automatically forwarding said access request to successive, different file systems whereby;

(a) if said access request is forwarded to a file system having said specified file system name, said first control signal is generated by said first means, in which case said second means either generates said first indication or said second indication, depending upon whether said file is successfully or unsucessfully accessed, respectively, and

(b) if said access request is forwarded to a file system not having said specified file system name, said first means generates said second control signal,

said third means ceasing to forward said access request after all of said file systems have been unsuccessful accessed and generating a third indication of an unsuccessfully access to said file directly to said one of said processors.

8. The data management system recited in claim 7, and further comprising means responsive to said access request generating means and to said access request forwarding means for forwarding said access request to said file systems in a predetermined pattern.