Re: fcntl(2) and other file systems like XFS

From: William J. Earl (wje@cthulhu.engr.sgi.com)
Date: Mon Mar 13 2000 - 21:56:09 EST


Jim Mostek writes:
>
> I don't see a callout from sys_fcntl into a file system specific routine
> (other than for file locking). There is a lock callout in
> the file operations that can be invoked in fcntl_getlk/fcntl_setlk/...
> (I'm looking in 2.3.42). But, this is different than file system specific
> fcntls. There is a call to sock_fcntl if the inode is a socket. But, I
> don't see a call for a file system specific fcntl in sys_fcntl..
>
> XFS has several fcntls for things like preallocating space. This is used
> by some applications who want very large files. This let's a file system
> allocate the space all at once.
>
> Has the issue of a file_operation callout for fcntl gone around before?
> Anyone opposed to adding this? I don't think this belongs in the
> inode_operations.

       As I understand it, Linux does do this sort of thing via ioctl(),
not fcntl(). The logic is that fcntl() is for attributes of "file" objects.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Wed Mar 15 2000 - 21:00:27 EST