[PATCH 1/7] arm64: Add contiguous page flag shifts and constants
Jeremy Linton
jeremy.linton at arm.com
Wed Oct 7 10:00:19 PDT 2015
Add the number of pages required to form a contiguous range,
as well as some supporting constants.
Signed-off-by: Jeremy Linton <jeremy.linton at arm.com>
---
arch/arm64/include/asm/page.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h
index 7d9c7e4..33892ef 100644
--- a/arch/arm64/include/asm/page.h
+++ b/arch/arm64/include/asm/page.h
@@ -20,14 +20,20 @@
#define __ASM_PAGE_H
/* PAGE_SHIFT determines the page size */
+/* CONT_SHIFT determines the number of pages which can be tracked together */
#ifdef CONFIG_ARM64_64K_PAGES
#define PAGE_SHIFT 16
+#define CONT_SHIFT 5
#else
#define PAGE_SHIFT 12
+#define CONT_SHIFT 4
#endif
-#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
+#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
+#define CONT_SIZE (_AC(1, UL) << (CONT_SHIFT + PAGE_SHIFT))
+#define CONT_MASK (~(CONT_SIZE-1))
+
/*
* The idmap and swapper page tables need some space reserved in the kernel
* image. Both require pgd, pud (4 levels only) and pmd tables to (section)
--
2.4.3
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