Re: block device/VM question

[Peter T. Breuer]

"A month of sundays ago Thunder from the hill wrote:"
> On Tue, 27 Aug 2002, Peter T. Breuer wrote:
> > > Why so rough?
> > 
> > Rough? You mean "approximate"? I was working from my vague mamory of
> > what I read in the code on the train this morning.
> 
> No, rough. I meant, why not use sys_open()?

You mean do a syscall with flags O_DIRECT from within the driver?
I don't like syscalsl from kernel code, but if you say so, I'll think
about it.

> Certainly not, as I'm not using libc6. But my manpages are newer, the 
> latest version is appended. It might clear this issue to you.

Thanks.

> > Oh, well, thanks.I suppose you won't give me a recipe saying "do this
> > and your device won't be cached", but I'll follow the lead.
> 
> I can't, because I don't have your code here and can't tell your needs. I 
> just try to serve it all. (I mean it all depends not just on where you go, 
> but also on what you have.)

Mmm ..  I must say I don't see how.  Making all requests on a block
device not be cached by VMS seems to me to have a globally defined
semantics, not confined to my particular use or context! Are you
suggesting that it depends on the mode of access to the device? That I
can't control - I simply want ALL accesses to not be cached.

Peter