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

[Henry Zhao]

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 ?


-Henry