Re: [Xen-devel] [PATCH v3 04/20] xen/grant: Introduce helpers to split a page into grant

From: Julien Grall
Date: Fri Aug 28 2015 - 10:31:00 EST

Hi David,

On 20/08/15 10:51, David Vrabel wrote:
> On 07/08/15 17:46, Julien Grall wrote:
>> Currently, a grant is always based on the Xen page granularity (i.e
>> 4KB). When Linux is using a different page granularity, a single page
>> will be split between multiple grants.
>> The new helpers will be in charge to split the Linux page into grants and
>> call a function given by the caller on each grant.
>> Also provide an helper to count the number of grants within a given
>> contiguous region.
>> Note that the x86/include/asm/xen/page.h is now including
>> xen/interface/grant_table.h rather than xen/grant_table.h. It's
>> necessary because xen/grant_table.h depends on asm/xen/page.h and will
>> break the compilation. Furthermore, only definition in
>> interface/grant_table.h was required.
> Reviewed-by: David Vrabel <david.vrabel@xxxxxxxxxx>
> But...
>> +/* Helper to get to call fn only on the first "grant chunk" */
>> +static inline void gnttab_one_grant(struct page *page, unsigned int offset,
>> + unsigned len, xen_grant_fn_t fn,
>> + void *data)
> this gnttab_for_one_grant().

Will rename it on the next version.


Julien Grall
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at