Handling file commit and commit-delete operations in an overlay optimizer

One or more computer storage media storing computer executable instruction which when executed by one or more processors implement a method for handling a commit or commit-delete operation, the method comprising:

• receiving, at a lower filter that is positioned below a write filter in a file system stack, a first create operation that was initiated by the write filter in response to a commit or commit-delete operation, the first create operation identifying a file to be opened;
• determining that a copy of the file identified in the first create operation is stored in an overlay cache;
• initiating a second create operation to open the file targeted by the first create operation;
• obtaining, from the second create operation, a handle to the copy of the file that is stored in the overlay cache;
• modifying the first create operation to include the handle;
• and
• completing the first create operation to thereby cause the write filter to perform the commit or commit-delete operation using the handle to the copy of the file that is stored in the overlay cache.

A method, performed by an overlay optimizer that includes an upper filter positioned above a write filter in a file system stack and a lower filter positioned below the write filter, for handling a commit or commit-delete operation, the method comprising:

• receiving, by the lower filter and via a preoperation callback routine, a first create operation that identifies a file to be opened;
• determining, by the lower filter, that a copy of the file identified in the first create operation is stored in an overlay cache;
• initiating, by the lower filter, a second create operation to open the file targeted by the first create operation;
• obtaining, from the second create operation, a handle to the copy of the file that is stored in the overlay cache;
• modifying the first create operation to include the handle;
• and
• completing, by the lower filter and in the preoperation callback routine, the first create operation.