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| author | Julien Grall <julien.grall@citrix.com> | 2015-06-19 18:05:06 +0100 |
|---|---|---|
| committer | David Vrabel <david.vrabel@citrix.com> | 2015-10-23 14:20:34 +0100 |
| commit | 3922f32c1e6db2e096ff095a5b8af0b940b97508 (patch) | |
| tree | 5170cad0c1b2e55c7332aeed768423e145a31952 /include/xen | |
| parent | 008c320a96d218712043f8db0111d5472697785c (diff) | |
| download | linux-3922f32c1e6db2e096ff095a5b8af0b940b97508.tar.bz2 | |
xen/grant: Add helper gnttab_page_grant_foreign_access_ref_one
Many PV drivers contain the idiom:
pfn = page_to_gfn(...) /* Or similar */
gnttab_grant_foreign_access_ref
Replace it by a new helper. Note that when Linux is using a different
page granularity than Xen, the helper only gives access to the first 4KB
grant.
This is useful where drivers are allocating a full Linux page for each
grant.
Also include xen/interface/grant_table.h rather than xen/grant_table.h in
asm/page.h for x86 to fix a compilation issue [1]. Only the former is
useful in order to get the structure definition.
[1] Interdependency between asm/page.h and xen/grant_table.h which result
to page_mfn not being defined when necessary.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Diffstat (limited to 'include/xen')
| -rw-r--r-- | include/xen/grant_table.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index 05b5b08c2afc..e17a4b381a16 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -131,6 +131,15 @@ void gnttab_cancel_free_callback(struct gnttab_free_callback *callback); void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid, unsigned long frame, int readonly); +/* Give access to the first 4K of the page */ +static inline void gnttab_page_grant_foreign_access_ref_one( + grant_ref_t ref, domid_t domid, + struct page *page, int readonly) +{ + gnttab_grant_foreign_access_ref(ref, domid, xen_page_to_gfn(page), + readonly); +} + void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid, unsigned long pfn); |