Fork us on GitHub Follow us on Facebook Follow us on Twitter

Changes between Version 2 and Version 3 of FSDesign

2009-07-13T09:12:19Z (12 years ago)
Jakub Jermář


  • FSDesign

    v2 v3  
    2828functionality by any other means. Each file system request forwarded to VFS
    2929is composed of one or more IPC phone calls.
     31== VFS server == #FSDesignVFS
     33The VFS server is the focal point of and also the most complex element of
     34the file system support in the HelenOS operating system. It exists as a
     35standalone user task. We can talk about the VFS frontend and VFS backend.
     37The frontend is responsible for accepting requests from the client tasks.
     38Their arguments are either absolute file paths, file handles of already
     39opened files, and in some special cases also VFS triplets (see below).
     41If the argument is a file path, VFS uses the ''vfs_lookup_internal()'' function to
     42translate the path into the so called VFS triplet. A VFS triplet is an ordered
     43triplet containing a global handle of the file system instance, a global device
     44handle and a file index. Thus a VFS triplet uniquely identifies a file on
     45some file system instance.