Re: f_ops flag to speed up compatible ioctls in linux kernel

Roland Dreier
2004-09-01T16:02:44Z

Albert> Per-command parameters included?

Albert> People really do want private syscalls. An ioctl is that,
Albert> in a namespace defined by the file descriptor. So ioctl()
Albert> provides local scope to something that would otherwise be
Albert> global.

Yes, this is exactly right. One issue raised by this thread is that
the ioctl32 compatibility code only allows one compatibility handler
per ioctl number. It seems that this creates all sorts of
possibilities for mayhem because it makes the ioctl namespace global
in scope in some situations. Does anyone have any thoughts on if/how
this should be addressed.

- Roland