hugetlb: ensure hugepage access is denied if hugepages are not supported

[platform/adaptation/renesas_rcar/renesas_kernel.git] / mm / internal.h

diff --git a/mm/internal.h b/mm/internal.h
index 7e145e8..3e91000 100644 (file)
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -83,7 +83,6 @@ extern unsigned long highest_memmap_pfn;
  */
 extern int isolate_lru_page(struct page *page);
 extern void putback_lru_page(struct page *page);
-extern unsigned long zone_reclaimable_pages(struct zone *zone);
 extern bool zone_reclaimable(struct zone *zone);
 
 /*
@@ -143,9 +142,11 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
 #endif
 
 /*
- * function for dealing with page's order in buddy system.
- * zone->lock is already acquired when we use these.
- * So, we don't need atomic page->flags operations here.
+ * This function returns the order of a free page in the buddy system. In
+ * general, page_zone(page)->lock must be held by the caller to prevent the
+ * page from being allocated in parallel and returning garbage as the order.
+ * If a caller does not hold page_zone(page)->lock, it must guarantee that the
+ * page cannot be allocated or merged in parallel.
  */
 static inline unsigned long page_order(struct page *page)
 {
@@ -369,5 +370,6 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone,
 #define ALLOC_HIGH             0x20 /* __GFP_HIGH set */
 #define ALLOC_CPUSET           0x40 /* check for correct cpuset */
 #define ALLOC_CMA              0x80 /* allow allocations from CMA areas */
+#define ALLOC_FAIR             0x100 /* fair zone allocation */
 
 #endif /* __MM_INTERNAL_H */