Can be filled in by open, to use direct I/O on this file. Introduced in version 2.4
File handle. May be filled in by filesystem in open(). Available in all other file operations
Old file handle, don't use
Open flags. Available in open() and release()
Indicates a flush operation. Set in flush operation, also maybe set in highlevel lock operation and lowlevel release operation. Introduced in version 2.6
Can be filled in by open, to indicate, that cached file data need not be invalidated. Introduced in version 2.4
Lock owner id. Available in locking operations and flush
Can be filled in by open, to indicate that the file is not seekable. Introduced in version 2.8
Padding. Do not use
In case of a write operation indicates if this was caused by a writepage