Re: How to handle console devices

From: Alan Cox
Date: Tue Sep 29 2009 - 18:47:28 EST


> I don't know what the best way is to accomplish this. Create dummy
> inode and file structs and pass them to the usual tty_open() routine?
> (But then what about hangup event handling?) What do you think?

What I long term envisioned was that

- Every tty (or at least every interesting tty) would have a tty_port
object for the hardware [done now for all consoles but vt]
- Every tty port object would have an "output" method
- The tty->termios would move to the tty_port
- The tty receive buffers would move to the tty_port (only needed for a
console that supports input)

At that point
- The tty lock/refcount isn't needed all the time for the receive data
paths which speeds it up a fair bit
- A console can be implemented without a tty_struct anywhere in sight
- Flow control and speed setting can be done on hardware generically on
resume paths

That fixes the lifetime and magic object invention issues that plague the
current console.

I still think that is the right way to fix it.

Alan
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