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.

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.

Abstract: A model in which filter drivers are managed to receive callbacks for I/O requests in which the filter drivers have registered an interest. Per-volume instances of filter drivers register with a filter manager for pre-callbacks (for I/O to the file system) and post-callbacks (for I/O from the file system), and identify which I/O requests (e.g., create, read, write) they are registering to receive callbacks. The filter manager orders the instances for callbacks. When an I/O request is received, the filter manager converts the I/O request to callback data and calls the interested filters in the callback order, whereby the filter instances can process the I/O data. As the request returns from the file system, filters desiring post callbacks are called in the reverse order. Efficient context management for the filters and other functions, such as non-reentrant file I/O, are also provided by the model.

Abstract: The invention provides a system and method for dynamically unloading file system filters in a stacked-call-back model where filters are stacked one on top of the other to form a filter stack. A filter manager keeps track of the progress of each I/O operation and calls each filter in turn with the filter returning after it has completed processing the given operation. The filter manager dynamically unloads a filter (or an instance of a filter) that is positioned at any position in the filter stack in a reasonable amount of time while I/O operations are actively being processed. The filter/filter instance can be unloaded with outstanding I/O operations on the filter either hosted by the filter or pended by other filters. I/O operations are canceled, completed or drained in order to unload the filter or filter instance. A filter may veto the unloading of the filter.