xen/public: grant-table: Specificy the size of the grant

The grant is always 4KB irrespectively of the page granularity of the
guest.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
---

Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Keir Fraser <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>

diff --git a/xen/include/public/grant_table.h b/xen/include/public/grant_table.h
index e9393fdd00a23980dd343fcfcc075346a09a1a39..67a250d4f29149a4ab24a258cf57251e31cebd32 100644 (file)
--- a/xen/include/public/grant_table.h
+++ b/xen/include/public/grant_table.h
@@ -51,6 +51,11 @@
  * know the real machine address of a page it is sharing. This makes
  * it possible to share memory correctly with domains running in
  * fully virtualised memory.
+ *
+ * The size of a grant is always 4KB irrespectively of the page
+ * granularity of the guest. This is means that when the guest is using
+ * 64KB page granularity, it will have to split the page in 4KB chunks
+ * and request a grant for every of them.
  */
 
 /***********************************