US5603019A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Takeover technique for networked virtual filesystems
Assignee: International Business Machines Corp
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Filing: 1994-07-25
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Granted: 1997-02-11
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Expires: 2014-07-25
Abstract
Abstract A system and method for allowing a distributed, coherent network filesystem to have virtual filesystem instantiations existent on any number of client nodes as well as on the server node that maintains the physical instantiation. On the server node only one image of the filesystem is visible even though two instantiations (physical and virtual) have been realized on that node. The rendering the physical instantation invisible and inaccessible is accomplished by performing a "takeover" of the physical filesystems data structures by the virtual filesystems mounting subroutines.
Inventors
- 👤 William A. Kish
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:13
CPC Classifications
G; G06; G06F; G06F16/00; G06F16/10; Y; Y10; Y10S; Y10S707/00; Y10S707/99951; Y10S707/99956
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
154 words
A method for controlling access to a first networked virtual filesystem by local users of a node in a networked computing system, comprising the steps of: (a) mounting the first networked virtual filesystem on the node, (b) mounting a second networked virtual filesystem on the node; (c) subsequent to step (a), preventing direct access to the first networked virtual filesystem by the local users; (d) subsequent to step (b), routing all requests for access to the first networked virtual filesystem by the local users to the first networked virtual filesystem by way of the second networked virtual filesystem; (e) providing the first networked virtual filesystem with a flag which depending on its state will alternatively cause the first networked virtual filesystem to be or not to be reported to certain processes; and, (f) setting the state of the flag to cause the first networked virtual filesystem not to be reported to the certain processes.
Claim 2
Independent Claim
154 words
A method for controlling access to a first networked virtual filesystem by local users of a node in a networked computing system, comprising the steps of: (a) mounting the first networked virtual filesystem on the node, (b) mounting a second networked virtual filesystem on the node; (c) subsequent to step (a), preventing direct access to the first networked virtual filesystem by the local users; (d) subsequent to step (b), routing all requests for access to the first networked virtual filesystem by the local users to the first networked virtual filesystem by way of the second networked virtual filesystem; (e) providing the first networked virtual filesystem with a flag which depending on its state will alternatively cause the first networked virtual filesystem to be or not to be reported to certain processes; and, (f) setting the state of the flag to cause the first networked virtual filesystem not to be reported to the certain processes.
Claim 3
Dependent Claim
32 words
The method of claim 1 wherein the first networked virtual filesystem is a coupled to a physical filesystem and wherein the first networked virtual filesystem routes the requests to the physical filesystem.
Claim 4
Dependent Claim
12 words
The method of claim 2 wherein the node is a server node.
Claim 5
Dependent Claim
21 words
The method of claim 3 wherein presence of the physical filesystem is hidden from the local users of the server node.
Claim 6
Independent Claim
114 words
A method for having a new virtual filesystem control access to a previously mounted virtual filesystem of a unix style logical file system, said method comprising the steps of: a) replacing mount point pointers of the old virtual filesystem by those of the new virtual file system, b) setting the new virtual file system takeover pointer to point to the old virtual file system, c) setting a flag in the data structures of the old virtual filesystem to indicate that it should be hidden from certain system calls, and, d) setting pointers in the internal data structures of new virtual file system to reference the internal data structures of the old virtual file system.
Claim 7
Independent Claim
114 words
A method for having a new virtual filesystem control access to a previously mounted virtual filesystem of a unix style logical file system, said method comprising the steps of: a) replacing mount point pointers of the old virtual filesystem by those of the new virtual file system, b) setting the new virtual file system takeover pointer to point to the old virtual file system, c) setting a flag in the data structures of the old virtual filesystem to indicate that it should be hidden from certain system calls, and, d) setting pointers in the internal data structures of new virtual file system to reference the internal data structures of the old virtual file system.
Claim 8
Independent Claim
171 words
A method for controlling access to a physical filesystem by local clients of a server node in a networked computing system, comprising the steps of: (a) mounting a first networked virtual filesystem on the server node, the first networked virtual filesystem being coupled to the physical filesystem; (b) mounting a second networked virtual filesystem on the server node; (c) subsequent to step (a), preventing direct access to the first networked virtual filesystem by the local clients; (d) subsequent to step (b), routing all requests for accesses to the physical filesystem by the local clients to the first networked virtual filesystem by way of the second networked virtual filesystem; (e) providing a flag which depending on its state will alternatively cause the first networked virtual filesystem to be or not to be reported to certain processes, and; (f) hiding existence of the first networked virtual filesystem from the local clients by setting the state of the flag to cause the first networked virtual filesystem not to be reported to the certain processes.
Claim 9
Independent Claim
171 words
A method for controlling access to a physical filesystem by local clients of a server node in a networked computing system, comprising the steps of: (a) mounting a first networked virtual filesystem on the server node, the first networked virtual filesystem being coupled to the physical filesystem; (b) mounting a second networked virtual filesystem on the server node; (c) subsequent to step (a), preventing direct access to the first networked virtual filesystem by the local clients; (d) subsequent to step (b), routing all requests for accesses to the physical filesystem by the local clients to the first networked virtual filesystem by way of the second networked virtual filesystem; (e) providing a flag which depending on its state will alternatively cause the first networked virtual filesystem to be or not to be reported to certain processes, and; (f) hiding existence of the first networked virtual filesystem from the local clients by setting the state of the flag to cause the first networked virtual filesystem not to be reported to the certain processes.
Claim 10
Dependent Claim
24 words
The method of claim 6 comprising the further step of exporting contents of the physical filesystem to other nodes of the networked computing system.
Claim 11
Dependent Claim
45 words
The method of claim 6 wherein the requests for accesses by the local clients are directed to the second networked virtual filesystem by manipulating data structures that describe the first networked virtual filesystem and instantiating new data structures that describe the second networked virtual filesystem.
Claim 12
Dependent Claim
30 words
The method of claim 6 wherein the first networked virtual filesystem does not include a filesystem coherency protocol and wherein the second virtual networked filesystem includes a filesystem coherency protocol.
Claim 13
Dependent Claim
35 words
The system of claim 9 wherein the causing is by means of manipulating the data structures that describe the first networked virtual filesystem and instantiating new data structures that describe the second networked virtual filesystem.
Claim 14
Independent Claim
176 words
A system for controlling accesses to a physical filesystem by local users of a server node in a networked computing system, comprising: a physical filesystem mounted on the server node; a first networked virtual filesystem mounted on the server node and coupled to the physical filesystem; a flag associated with the first virtual filesystem, which depending on its state will cause the first networked virtual filesystem to be or not to be reported to certain processes; means for setting the state of the flag to cause the first networked virtual filesystem not to be reported to the certain processes; a second networked virtual filesystem mounted on the server node and coupled to the physical filesystem, at least one other node of the computing system having a copy of the second networked virtual filesystem mounted thereon; and, means for causing the second networked virtual filesystem to capture all local accesses to the physical filesystem by the first networked virtual filesystem and for exporting the contents of the physical filesystem to other nodes of the networked computing system.
Claim 15
Independent Claim
176 words
A system for controlling accesses to a physical filesystem by local users of a server node in a networked computing system, comprising: a physical filesystem mounted on the server node; a first networked virtual filesystem mounted on the server node and coupled to the physical filesystem; a flag associated with the first virtual filesystem, which depending on its state will cause the first networked virtual filesystem to be or not to be reported to certain processes; means for setting the state of the flag to cause the first networked virtual filesystem not to be reported to the certain processes; a second networked virtual filesystem mounted on the server node and coupled to the physical filesystem, at least one other node of the computing system having a copy of the second networked virtual filesystem mounted thereon; and, means for causing the second networked virtual filesystem to capture all local accesses to the physical filesystem by the first networked virtual filesystem and for exporting the contents of the physical filesystem to other nodes of the networked computing system.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-02-11 | 2000-08-12 | 2001-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-02-11 | 2004-08-12 | 2005-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-02-11 | 2008-08-12 | 2009-02-11 | $7700.00 | Window Closed / Lapsed |