[PATCH pciaccess 2/2] vgaarb: read back vga count when setting new decoding

[Tiago Vignatti]

On Tue, Jun 22, 2010 at 04:15:37AM +0200, ext Henry Zhao wrote:
> On 06/21/10 19:04, Henry Zhao wrote:
> > Decode kernel operation can also change vga refcount, so we need to 
> > read back
> > the information when calling it.
> >
> > Signed-off-by: Tiago Vignatti<tiago.vignatti at nokia.com 
> > <http://lists.x.org/mailman/listinfo/xorg-devel>>
> > ---
> >  src/common_vgaarb.c |    7 +++++++
> >  1 files changed, 7 insertions(+), 0 deletions(-)
> >
> > diff --git a/src/common_vgaarb.c b/src/common_vgaarb.c
> > index f09d513..c94b362 100644
> > --- a/src/common_vgaarb.c
> > +++ b/src/common_vgaarb.c
> > @@ -263,6 +263,13 @@ pci_device_vgaarb_decodes(int new_vgaarb_rsrc)
> >      ret = vgaarb_write(pci_sys->vgaarb_fd, buf, len);
> >      if (ret == 0)
> >          dev->vgaarb_rsrc = new_vgaarb_rsrc;
> > +
> > +    ret = read(pci_sys->vgaarb_fd, buf, BUFSIZE);
> > +    if (ret<= 0)
> > +        return -1;
> > +
> > +    parse_string_to_decodes_rsrc(buf,&pci_sys->vga_count, NULL);
> > +
> >      return ret;
> >  }
> >
> 
> pci_device_vgaarb_decodes() is called from userland
> xf86VGAarbiterDeviceDecodes(). How can it be related to decode
> kernel operation ?  Or do we really need to get vga count change
> every time when making a kernel call ? 

Not sure I understood what you wanted to say, but maybe this commit answer
your questions:

http://cgit.freedesktop.org/~vignatti/xserver/commit/?h=vgaarb-fixes&id=f729a7b98535137311ab4cf6abc884bc0d771206

Note that it's not applied in upstream.


Cheers,

             Tiago