[PATCH 03/10] xen/arm: introduce PGC_reserved

[Penny Zheng <penny.zheng@xxxxxxx>]

In order to differentiate pages of static memory, from those allocated from
heap, this patch introduces a new page flag PGC_reserved to tell.

New struct reserved in struct page_info is to describe reserved page info,
that is, which specific domain this page is reserved to.

Helper page_get_reserved_owner and page_set_reserved_owner are
designated to get/set reserved page's owner.

Struct domain is enlarged to more than PAGE_SIZE, due to newly-imported
struct reserved in struct page_info.

Signed-off-by: Penny Zheng <penny.zheng@xxxxxxx>
---
 xen/include/asm-arm/mm.h | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h
index 0b7de3102e..d8922fd5db 100644
--- a/xen/include/asm-arm/mm.h
+++ b/xen/include/asm-arm/mm.h
@@ -88,7 +88,15 @@ struct page_info
          */
         u32 tlbflush_timestamp;
     };
-    u64 pad;
+
+    /* Page is reserved. */
+    struct {
+        /*
+         * Reserved Owner of this page,
+         * if this page is reserved to a specific domain.
+         */
+        struct domain *domain;
+    } reserved;
 };
 
 #define PG_shift(idx)   (BITS_PER_LONG - (idx))
@@ -108,6 +116,9 @@ struct page_info
   /* Page is Xen heap? */
 #define _PGC_xen_heap     PG_shift(2)
 #define PGC_xen_heap      PG_mask(1, 2)
+  /* Page is reserved, referring static memory */
+#define _PGC_reserved     PG_shift(3)
+#define PGC_reserved      PG_mask(1, 3)
 /* ... */
 /* Page is broken? */
 #define _PGC_broken       PG_shift(7)
@@ -161,6 +172,9 @@ extern unsigned long xenheap_base_pdx;
 #define page_get_owner(_p)    (_p)->v.inuse.domain
 #define page_set_owner(_p,_d) ((_p)->v.inuse.domain = (_d))
 
+#define page_get_reserved_owner(_p)    (_p)->reserved.domain
+#define page_set_reserved_owner(_p,_d) ((_p)->reserved.domain = (_d))
+
 #define maddr_get_owner(ma)   (page_get_owner(maddr_to_page((ma))))
 
 #define frame_table ((struct page_info *)FRAMETABLE_VIRT_START)
-- 
2.25.1