Re: [PATCH/RFC] I/O-check interface for driver's error handling

[Jesse Barnes <jbarnes@engr.sgi.com>]

On Friday, March 4, 2005 5:54 am, Pavel Machek wrote:
> Hi!
>
> > > If there's no ->error method, at leat call ->remove so one device only
> > > takes itself down.
> > >
> > > Does this make sense?
> >
> > This was my thought too last time we had this discussion.  A completely
> > asynchronous call is probably needed in addition to Hidetoshi's proposed
> > API, since as you point out, the driver may not be running when an error
> > occurs (e.g. in the case of a DMA error or more general bus problem). 
> > The async
>
> Hmm, before we go async way (nasty locking, no?) could driver simply
> ask "did something bad happen while I was sleeping?" at begining of each
> function?

This is what Seto is proposing, aiui.  I.e. calls around I/O so you can 
gracefully handle errors during that I/O.

> For DMA problems, driver probably has its own, timer-based,
> "something is wrong" timer, anyway, no?

The idea is to allow them to do something like that, or consolidate such 
threads in a platform specific error handling thread or interrupt handler 
that can call a driver's ->dma_error(dev) routine (or ->error(dev, ERROR_DMA) 
or whatever) routine.

Jesse