[Intel-gfx] [PATCH 2/2] drm/i915: properly prefault for pread/pwrite

[Daniel Vetter]

Oosp, forgotten to actually put Keith on the To: ... not enough coffee,
yet.
-Daniel

On Sun, Oct 23, 2011 at 12:18:30PM +0200, Daniel Vetter wrote:
> Hi Keith,
> 
> This patch isn't in your -next pull. This papers over a spurious -EFAULT
> in the pwrite/pread paths that actually gets hit in the wild. The real fix
> in the form of a almost complete rewrite of the pwrite/pread paths won't
> be ready for 3.2.
> 
> Do you want me to implement Chris' beautification suggestion? The code
> as-is is copied over from the pagecache prefault helper. Otherwise please
> consider merging for 3.2.
> 
> Yours, Daniel
> 
> On Wed, Sep 28, 2011 at 12:24:04PM +0100, Chris Wilson wrote:
> > > +	if (ret == 0) {
> > > +		if (((unsigned long)uaddr & PAGE_MASK) !=
> > > +				((unsigned long)end & PAGE_MASK))
> > This is a little ugly. Perhaps,
> > 
> >   #define page_align(addr) ((unsigned long)addr & PAGE_MASK)
> >   if (page_align(uaddr) != page_align(end))
> > 
> > Otherwise, both are
> > Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
> > -Chris
> > 
> > -- 
> > Chris Wilson, Intel Open Source Technology Centre
> 
> -- 
> Daniel Vetter
> Mail: daniel at ffwll.ch
> Mobile: +41 (0)79 365 57 48

-- 
Daniel Vetter
Mail: daniel at ffwll.ch
Mobile: +41 (0)79 365 57 48