Okay... I've been playing around with implementing my own file system (as an exercise). I'd like to implement it as a standalone module. However, I notice that certain data structure that are defined in kernel header files have file system specific fields in them. For example, I'm looking at the definition of struct inode in include/linux/fs.h. The member "u" is a union of file system specific structures where each file system stores information related to it (or so I assume). It seems to me that I need to store information specific to my file system too. However, I'm reluctant to define my own structure and then edit include/linux/fs.h to include it. In theory wouldn't that make it impossible to support my file system as a "pure" binary module? The main kernel would have to be recompiled to account for the possibly different size of struct inode. I couldn't just insmod my filesystem module into a kernel what was not thusly prepared. How do people implement file systems as modules? Can it be done? Peter Wait... wait... I think I might be answering my own question. I see that the "u" member of struct inode has a void * named generic_ip. So could I allocate my own file system specific structure (elsewhere) and put its address into that member? Of course I'd have to manage those file system specific structures (what a pain) but I suppose that could be done. Is this the right track? - Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/
