Supporting file exclusions and commits in disk-based write filters

One or more computer storage media storing computer executable instructions which when executed on a client device implement a disk-based write filter that provides write filter protection to a volume while also supporting file exclusions by performing the following method:

• receiving, at a supporting driver of the disk-based write filter that is loaded above a file system driver for the volume, an I/O request for opening a file;
• determining, by the supporting driver, that the file should be excluded from the write filter protection;
• in response to the determination, retrieving, by the supporting driver, disk sector information for the file;
• sending, by the supporting driver, the disk sector information to a filter driver of the disk-based write filter that is loaded below the file system driver;
• and
• employing, by the filter driver, the disk sector information to exclude the file from the write filter protection.

A method, implemented by a disk-based write filter that provides write filter protection to a volume, for supporting file exclusions, the method comprising:

• receiving, at a supporting driver of the disk-based write filter, an IRP_MJ_CREATE request for a file;
• as part of handling the IRP_MJ_CREATE request for the file:
• determining, by the supporting driver, that the file should be excluded from the write filter protection;
• in response to the determination, retrieving, by the supporting driver, disk sector information for the file;
• sending, by the supporting driver, the disk sector information to a filter driver of the disk-based write filter to cause the filter driver to employ the disk sector information to exclude the file from the write filter protection;
• and
• setting, by the supporting driver, a context of the file to indicate that the file is excluded.