Re: [PATCH v13 15/19] xen/grant-table: Refactor gnttab_init

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Fri, 3 Jan 2014, Konrad Rzeszutek Wilk wrote:
> We have this odd scenario of where for PV paths we take a shortcut
> but for the HVM paths we first ioremap xen_hvm_resume_frames, then
> assign it to gnttab_shared.addr. This is needed because gnttab_map
> uses gnttab_shared.addr.
> 
> Instead of having:
> 	if (pv)
> 		return gnttab_map
> 	if (hvm)
> 		...
> 
> 	gnttab_map
> 
> Lets move the HVM part before the gnttab_map and remove the
> first call to gnttab_map.
> 
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> Reviewed-by: David Vrabel <david.vrabel@citrix.com>

As I wrote in my reply to the previous version of the patch, you can
have my acked-by, except for the spurious code style fix mixed-up with
the other changes.


>  drivers/xen/grant-table.c | 13 ++++---------
>  1 file changed, 4 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
> index 99399cb..cc1b4fa 100644
> --- a/drivers/xen/grant-table.c
> +++ b/drivers/xen/grant-table.c
> @@ -1173,22 +1173,17 @@ static int gnttab_setup(void)
>  	if (max_nr_gframes < nr_grant_frames)
>  		return -ENOSYS;
>  
> -	if (xen_pv_domain())
> -		return gnttab_map(0, nr_grant_frames - 1);
> -
> -	if (gnttab_shared.addr == NULL) {
> +	if (xen_feature(XENFEAT_auto_translated_physmap) && gnttab_shared.addr == NULL)
> +	{
>  		gnttab_shared.addr = xen_remap(xen_hvm_resume_frames,
> -						PAGE_SIZE * max_nr_gframes);
> +					       PAGE_SIZE * max_nr_gframes);
>  		if (gnttab_shared.addr == NULL) {
>  			pr_warn("Failed to ioremap gnttab share frames (addr=0x%08lx)!\n",
>  					xen_hvm_resume_frames);
>  			return -ENOMEM;
>  		}
>  	}
> -
> -	gnttab_map(0, nr_grant_frames - 1);
> -
> -	return 0;
> +	return gnttab_map(0, nr_grant_frames - 1);
>  }
>  
>  int gnttab_resume(void)
> -- 
> 1.8.3.1
>