Virtual universal naming convention name space over local file system

• US 7,836,079 B2
• Filed: 04/07/2006
• Issued: 11/16/2010
• Est. Priority Date: 04/07/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Brown, Eileen, Buban, Garret J., Kumar, Rohan, Christiansen, Neal R.
• Primary Examiner(s): Kim; Charles
• Assistant Examiner(s): Girma; Anteneh
• Application Number:
  US11/279,022
• Publication Number:
  US 20070239720A1
• Time in Patent Office: 1,684 Days
• Field of Search: 707/9, 707/1, 707/3
• US Class Current: 707/783
• CPC Class Codes: G06F 16/10 File systems; File servers

Abstract

Systems and methods that create a virtual name space of Universal Naming Convention (UNC) over a local file system (e.g., drive letter based names), via employing a UNC provider and filter arrangement that changes a name in the file object to reparse it to a volume where the local file exists. A name in the file object is changed to a local name (e.g., morphed name); subsequently reparsed and forwarded to a Name Space Owner component (NSO). As such, a request can originate from a UNC stack and reparsed on the local stack. The name space is presented to an application in UNC format, while the underlying file write occur in the file system.

Claims

1. A computer implemented system comprising:

at least one processor; and

a memory that retains code instructions that when executed by the at least one processor effect at least the following;

a user-mode Universal Naming Convention (UNC) name space accessible to an application that issues a file input/output (I/O) call from a remote UNC stack, wherein the user-mode UNC name space is transferable amongst a plurality of computers, such that the UNC name space is exposed in UNC format while any underlying file writes occur in a local file system volume;

a UNC provider that is configured to perform the following;

create a virtual UNC name space over a local file system;

change a name in a file object of the file I/O call to reparse the file object with the changed name on to the local file system volume where the local file associated with the UNC name space resides, wherein the reparse occurs on a local file system stack such that the user-mode UNC name space is exposed in UNC format while any underlying file writes occur in the local file system, enabling both the UNC provider and a local namespace provider to use the same data store; and

uniquely mark any opened file objects that have a changed name changed via the UNC provider such that the UNC-changed-name opened files are differentiated from files that are opened using a local name to allow a local file-side filter to recognize UNC-changed-name files by their unique mark and respond to file open requests for UNC-changed-name files in a manner different than that for local files, allowing the application to interpret file I/O calls for both local and UNC namespaces that access the same data;

a user-mode Name Space Owner component (NSO) for maintenance of a mapping between the UNC name space and local names; and

a local file system filter block that restricts access to the local names to one or more components except the user-mode NSO.

2. The computer implemented system of claim 1 further comprising a UNC filter stack located between the UNC provider and an I/O manager, the I/O manager receives the file I/O call in a kernel mode.

3. The computer implemented system of claim 1, further comprising a UNC filter stack and MUP that are located between the UNC provider and an I/O manager.

4. The computer implemented system of claim 1 further comprising a Multiple UNC provider for determination of a file system that handles the file I/O call.

5. The computer implemented system of claim 1, wherein the user-mode NSO owns the user-mode UNC name space.

6. The computer implemented system of claim 1 further comprising a file system filter driver that identifies a prefix in a file name of the file object on the local files.

7. The computer implemented system of claim 1 further comprising a GUID returned by the NSO to the file system.

8. A computer implemented method comprising the following computer executable acts:

employing one or more processor to execute code instructions stored in a computer-readable medium, the code instructions when executed by the one or more processor perform at least the following acts;

originating a call on a Universal Naming Convention (UNC) stack by an application that interacts with a UNC name space, wherein the UNC name space is exposed in UNC format while any underlying file writes occur in a local file system volume;

creating a virtual UNC name space over a local file system;

reparsing a file object associated with the call to the local file system volume where a local file associated with the UNC name space resides, wherein the reparse occurs on a local file system stack such that the user-mode UNC name space is exposed in UNC format while any underlying file writes occur in the local file system, enabling both the UNC provider and a local namespace provider to use the same data store;

uniquely marking any opened file objects that have a changed name changed via the UNC provider such that the UNC-changed-name opened files are differentiated from files that are opened using a local name to allow a local file-side filter to recognize UNC-changed-name files by their unique mark and respond to file open requests for UNC-changed-name files in a manner different than that for local files, allowing the application to interpret file I/O calls for both local and UNC namespaces that access the same data;

exposing the UNC name space to the application in UNC format while processing a file associated with the call in a kernel-mode local file system;

owning and managing the UNC name space by a user mode process that interacts with the application; and

filter blocking file locations to limit access to a Name Space Owner that manages local names in the kernel-mode file system.

9. The computer implemented method of claim 8 further comprising writing an underlying file associated with the call in a file system of the local file system volume.

10. The computer implemented method of claim 8, the reparsing act further comprising changing a name in the file object for a reparse thereof to a volume where a local file resides.

11. The computer implemented method of claim 10 further comprising identifying a prefix that is associated with a changed name, via a filter driver.

12. The computer implemented method of claim 11 further comprising mapping between UNC file names and the file locations.

13. The computer implemented method of claim 10, the originating act further comprising creating a new file request and transferring the new file request to an Input/Output (I/O) manager for a handling thereof.

14. The computer implemented method of claim 13 further comprising identifying a storage location of a file associated with the call.

15. The computer implemented method of claim 14 further comprising forwarding reparsed object files to the storage location.

17. The computer implemented method of claim 8, further comprising transferring the UNC name space from a first machine to a second machine.

16. A computer implemented system comprising:

at least a processor to execute code instructions stored in a computer-readable medium, the code instructions when executed by at least the processor effect at least the following;

means for initiating a call on a user-mode Universal Naming Convention (UNC) stack from a remote UNC stack, wherein the user-mode UNC name space is transferable amongst a plurality of computers, such that the UNC name space is exposed in UNC format while any underlying file writes occur in a local file system volume;

means for creating a virtual UNC name space over a local file system;

means positioned on a local stack for changing a name in a file object of the call to reparse the file object with the changed name on to the local file system volume where the local file associated with the UNC name space resides, wherein the reparse occurs on a local file system stack such that the user-mode UNC name space is exposed in UNC format while any underlying file writes occur in the local file system, enabling both the UNC provider and a local namespace provider to use the same data store;

means for uniquely marking any opened file objects that have a changed name changed via the UNC provider such that the UNC-changed-name opened files are differentiated from files that are opened using a local name to allow a local file-side filter to recognize UNC-changed-name files by their unique mark and respond to file open requests for UNC-changed-name files in a manner different than that for local files, allowing the application to interpret file I/O calls for both local and UNC namespaces that access the same data; and

means for filtering access to file locations to one or more components except a component that manages local names in a kernel-mode file system related to the file object of the call.