1 files changed, 68 insertions, 0 deletions

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index ac3cb239a7ec..249c65e1d8ca 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -472,6 +472,60 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 					unsigned long flags);
 #endif /* HAVE_ARCH_HUGETLB_UNMAPPED_AREA */
 
+/*
+ * huegtlb page specific state flags.  These flags are located in page.private
+ * of the hugetlb head page.  Functions created via the below macros should be
+ * used to manipulate these flags.
+ *
+ * HPG_restore_reserve - Set when a hugetlb page consumes a reservation at
+ *	allocation time.  Cleared when page is fully instantiated.  Free
+ *	routine checks flag to restore a reservation on error paths.
+ */
+enum hugetlb_page_flags {
+	HPG_restore_reserve = 0,
+	__NR_HPAGEFLAGS,
+};
+
+/*
+ * Macros to create test, set and clear function definitions for
+ * hugetlb specific page flags.
+ */
+#ifdef CONFIG_HUGETLB_PAGE
+#define TESTHPAGEFLAG(uname, flname)				\
+static inline int HPage##uname(struct page *page)		\
+	{ return test_bit(HPG_##flname, &(page->private)); }
+
+#define SETHPAGEFLAG(uname, flname)				\
+static inline void SetHPage##uname(struct page *page)		\
+	{ set_bit(HPG_##flname, &(page->private)); }
+
+#define CLEARHPAGEFLAG(uname, flname)				\
+static inline void ClearHPage##uname(struct page *page)		\
+	{ clear_bit(HPG_##flname, &(page->private)); }
+#else
+#define TESTHPAGEFLAG(uname, flname)				\
+static inline int HPage##uname(struct page *page)		\
+	{ return 0; }
+
+#define SETHPAGEFLAG(uname, flname)				\
+static inline void SetHPage##uname(struct page *page)		\
+	{ }
+
+#define CLEARHPAGEFLAG(uname, flname)				\
+static inline void ClearHPage##uname(struct page *page)		\
+	{ }
+#endif
+
+#define HPAGEFLAG(uname, flname)				\
+	TESTHPAGEFLAG(uname, flname)				\
+	SETHPAGEFLAG(uname, flname)				\
+	CLEARHPAGEFLAG(uname, flname)				\
+
+/*
+ * Create functions associated with hugetlb page flags
+ */
+HPAGEFLAG(RestoreReserve, restore_reserve)
+
 #ifdef CONFIG_HUGETLB_PAGE
 
 #define HSTATE_NAME_LEN 32
@@ -531,6 +585,20 @@ extern unsigned int default_hstate_idx;
 
 #define default_hstate (hstates[default_hstate_idx])
 
+/*
+ * hugetlb page subpool pointer located in hpage[1].private
+ */
+static inline struct hugepage_subpool *hugetlb_page_subpool(struct page *hpage)
+{
+	return (struct hugepage_subpool *)(hpage+1)->private;
+}
+
+static inline void hugetlb_set_page_subpool(struct page *hpage,
+					struct hugepage_subpool *subpool)
+{
+	set_page_private(hpage+1, (unsigned long)subpool);
+}
+
 static inline struct hstate *hstate_file(struct file *f)
 {
 	return hstate_inode(file_inode(f));