[PATCH for-4.5 v7 15/21] xen/arm: Implement domain_get_maximum_gpfn

[Tamas K Lengyel <tklengyel@sec.in.tum.de>]

From: Julien Grall <julien.grall@linaro.org>

The function domain_get_maximum_gpfn is returning the maximum gpfn ever
mapped in the guest. We can use d->arch.p2m.max_mapped_gfn for this purpose.

We use this in xenaccess as to avoid the user attempting to set page
permissions on pages which don't exist for the domain, as a non-arch specific
sanity check.

Signed-off-by: Julien Grall <julien.grall@linaro.org>
---
 xen/arch/arm/mm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 0a243b0..e4a1e5e 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -954,7 +954,7 @@ int page_is_ram_type(unsigned long mfn, unsigned long mem_type)
 
 unsigned long domain_get_maximum_gpfn(struct domain *d)
 {
-    return -ENOSYS;
+    return d->arch.p2m.max_mapped_gfn;
 }
 
 void share_xen_page_with_guest(struct page_info *page,
-- 
2.1.0