Re: [Qemu-devel] [PATCH] honor IDE_DMA_BUF_SECTORS

[Samuel Thibault]

Avi Kivity, le Thu 26 Mar 2009 14:58:55 +0200, a écrit :
> Samuel Thibault wrote:
> >Avi Kivity, le Thu 26 Mar 2009 14:10:20 +0200, a écrit :
> >  
> >>I realize your use case will probably not trigger this, but it does 
> >>indicate you're limiting at the wrong layer.  It places the burden on 
> >>all callers of block format drivers instead of centralizing it.
> >>    
> >
> >Then it should be centralized in the block layer instead of placing the
> >burden on all block format drivers ;)
> >  
> 
> If other drivers need to do that, certainly.

In our case the other driver is specific to Xen.

> >One thing for instance that still have been overlooked although patches
> >have been sent is block-raw-posix' read/write_pread_aligned() that
> >consider partial read/writes as an error.  That's a bug.
> >  
> 
> Right.  Unrelated topic though?

Nope.  It's exactly the issue: read/write() may not be able to perform
the whole operation in just one go, and qemu should continue in that
case.

Samuel